methylcellulose and Disease-Models--Animal

We examined the effects of spices and herbs on Candida albicans to develop therapeutic tools against oral diseases such as oral candidiasis. C. albicans, a dimorphic fungus, is a component of the healthy human microbial flora. However, the excessive overgrowth of C. albicans causes oral candidiasis, and the symptoms, accompanied by severe inflammation, reduce the quality of life of elderly people. We found that spices such as clove (Syzygium aromaticum) and cassia (Cinnamomum aromaticum) exhibit inhibitory activity against Candida mycelial growth and show therapeutic efficacy in a murine oral candidiasis model. Our studies also demonstrated that the inhibitory activity of cinnamaldehyde was strengthened in parallel with a prolonged treatment time. Furthermore, when cinnamaldehyde in combination with methylcellulose was administered to the model mice, the therapeutic effect was potentiated. Here, we summarize up-to-date findings on how to use spices and herbs on a daily basis to improve or prevent oral problems such as oral candidiasis with the presentation of our recent data.

Topics: Acrolein; Animals; Candida albicans; Candidiasis, Oral; Cinnamomum aromaticum; Disease Models, Animal; Drug Resistance, Fungal; Humans; Methylcellulose; Mice; Plant Extracts; Plants, Medicinal; Spices; Syzygium

The medial division of the central nucleus of the amygdala (CeA(M)) and the lateral division of the bed nucleus of the stria terminalis (BNST(L)) are closely related. Both receive projections from the basolateral amygdala (BLA) and both project to brain areas that mediate fear-influenced behaviors. In contrast to CeA(M) however, initial attempts to implicate the BNST in conditioned fear responses were largely unsuccessful. More recent studies have shown that the BNST does participate in some types of anxiety and stress responses. Here, we review evidence suggesting that the CeA(M) and BNST(L) are functionally complementary, with CeA(M) mediating short- but not long-duration threat responses (i.e., phasic fear) and BNST(L) mediating long- but not short-duration responses (sustained fear or 'anxiety'). We also review findings implicating the stress-related peptide corticotropin-releasing factor (CRF) in sustained but not phasic threat responses, and attempt to integrate these findings into a neural circuit model which accounts for these and related observations.

Topics: Amygdala; Animals; Anxiety; Corticotropin-Releasing Hormone; Disease Models, Animal; Dose-Response Relationship, Drug; Fear; Light; Methylcellulose; Reflex, Startle; Septal Nuclei; Stress, Psychological

Thermosensitive. The effect of different polymer combinations on parameters like gelation time and temperature, rheological properties, texture, spreading coefficients, mucoadhesion, conjunctival irritation potential,. Both gelation time and temperature were significantly dependent on the concentrations of poloxamer 407 and additive polymers (chitosan and methyl cellulose), where it ranged from <10 s to several minutes. Mechanical properties investigated through texture analysis (hardness, adhesiveness, and cohesiveness) were dependent on composition. Promising spreading-ability, mucoadhesion, transcorneal permeation of L-carnosine, high ocular tolerability, and enhanced corneal epithelium wound healing were recorded for poloxamer 407/chitosan systems.

Topics: Administration, Topical; Animals; Carnosine; Chemistry, Pharmaceutical; Chitosan; Cornea; Corneal Ulcer; Delayed-Action Preparations; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Delivery Systems; Drug Liberation; Gels; Methylcellulose; Poloxamer; Rabbits; Rheology; Temperature; Wound Healing

To assess the efficacy of the novel clinical formulation of fenretinide (LAU-7b) for the treatment of allergic asthma. To study the association between LAU-7b treatment in allergic asthma and the modulation of very long chain ceramides (VLCC).. We used two allergens (OVA and HDM) to induce asthma in mouse models and we established a treatment protocol with LAU-7b. The severity of allergic asthma reaction was quantified by measuring the airway resistance, quantifying lung inflammatory cell infiltration (Haematoxylin and eosin stain) and mucus production (Periodic acid Schiff satin). IgE levels were measured by ELISA. Immunophenotyping of T cells was done using Fluorescence-activated cell sorting (FACS) analysis. The analysis of the specific species of lipids and markers of oxidation was performed using mass spectrometry.. Our data demonstrate that 10 mg/kg of LAU-7b was able to protect OVA- and HDM-challenged mice against increase in airway hyperresponsiveness, influx of inflammatory cells into the airways, and mucus production without affecting IgE levels. Treatment with LAU-7b significantly increased percentage of regulatory T cells and CD4. 9 days of 10 mg/kg of LAU-7b daily treatment protects the mice against allergen-induced asthma and restores VLCC levels in the lungs and plasma.

Topics: Allergens; Animals; Asthma; Ceramides; Clinical Protocols; Disease Models, Animal; Drug Compounding; Female; Fenretinide; Male; Methylcellulose; Mice; Ovalbumin; Pyroglyphidae

Back pain commonly arises from intervertebral disc (IVD) damage including annulus fibrosus (AF) defects and nucleus pulposus (NP) loss. Poor IVD healing motivates developing tissue engineering repair strategies. This study evaluated a composite injectable IVD biomaterial repair strategy using carboxymethylcellulose-methylcellulose (CMC-MC) and genipin-crosslinked fibrin (FibGen) that mimic NP and AF properties, respectively. Bovine ex vivo caudal IVDs were evaluated in cyclic compression-tension, torsion, and compression-to-failure tests to determine IVD biomechanical properties, height loss, and herniation risk following experimentally-induced severe herniation injury and discectomy (4 mm biopsy defect with 20% NP removed). FibGen with and without CMC-MC had failure strength similar to discectomy injury suggesting no increased risk compared to surgical procedures, yet no biomaterials improved axial or torsional biomechanical properties suggesting they were incapable of adequately restoring AF tension. FibGen had the largest failure strength and was further evaluated in additional discectomy injury models with varying AF defect types (2 mm biopsy, 4 mm cruciate, 4 mm biopsy) and NP removal volume (0%, 20%). All simulated discectomy defects significantly compromised failure strength and biomechanical properties. The 0% NP removal group had mean values of axial biomechanical properties closer to intact levels than defects with 20% NP removed but they were not statistically different and 0% NP removal also decreased failure strength. FibGen with and without CMC-MC failed at super-physiological stress levels above simulated discectomy suggesting repair with these tissue engineered biomaterials may perform better than discectomy alone, although restored biomechanical function may require additional healing with the potential application of these biomaterials as sealants and cell/drug delivery carriers.

Topics: Animals; Annulus Fibrosus; Biocompatible Materials; Biomechanical Phenomena; Carboxymethylcellulose Sodium; Cattle; Cross-Linking Reagents; Disease Models, Animal; Diskectomy; Fibrin; Hydrogels; In Vitro Techniques; Injections, Spinal; Intervertebral Disc Displacement; Iridoids; Materials Testing; Methylcellulose; Nucleus Pulposus

The immunogenicity of oral subunit vaccines is poor partly as a result of the harsh milieu of the gastrointestinal (GI) tract. For some pathogens that restrictedly inhabit the GI tract, a vaccine that works in situ may provide more potent protection than vaccines that operate parenterally. Yet, no appropriate delivery system is available for oral subunit vaccines. In this study, we designed HP55/poly( n-butylcyanoacrylate) (PBCA) nanoparticles (NPs) to carry Helicobacter pylori ( H. pylori) subunit vaccine CCF for oral administration in a prophylactic mice model. These NPs, which are synthesized using an interfacial polymerization method, protected the CCF antigen not only from the acidic pH in simulated gastric fluid (SGF, pH 1.2) but also from the proteolysis in simulated intestinal fluid (SIF, pH 7.4). Oral vaccination of mice with HP55/PBCA-CCF NPs promoted the production of serum antigen-specific antibodies, mucosal secretory IgA, and proinflammatory cytokines. Moreover, a Th1/Th17 response and augmented lymphocytes were found in the gastric tissue of HP55/PBCA-CCF NP-immunized mice, which might eventually limit H. pylori colonization. Collectively, these results indicate that HP55/PBCA NPs are promising carriers against the severe situation of the GI tract and thereby may be further utilized for other orally administrated vaccines or drugs.

Topics: Administration, Oral; Animals; Antigens, Bacterial; Bacterial Vaccines; Cyanoacrylates; Disease Models, Animal; Drug Carriers; Female; Gastrointestinal Tract; Helicobacter Infections; Helicobacter pylori; Humans; Immunity, Cellular; Immunogenicity, Vaccine; Male; Methylcellulose; Mice; Mice, Inbred BALB C; Nanoparticles; Proteolysis; Vaccines, Subunit

Human prolactin (PRL) is a well-known hormone for pituitary of lactation and reproduction, but it also has immunostimulatory effect in some inflammatory or autoimmune diseases including psoriasis, which has not been well elucidated. This study aimed to determine the relationship between PRL and psoriasis through clinical case-control studies, and explore the function of PRL in the pathogenesis of imiquimod (IMQ)-induced psoriasis-like mouse model. Serum from patients with psoriasis vulgaris (PsV), patients with erythrodermic psoriasis, and healthy controls (HCs) were collected for PRL test. Skin biopsies were collected for PRL, PRL receptors (PRLRs), cytokines mRNA level determination, PRL immunohistochemistry and PRL Western blotting. Mice were divided into four groups (each n = 6): control group (CON), IMQ group, anti-PRL group and solvent group. Anti-PRL group and solvent group mice were treated with PRL antagonist (cabergoline) and the solvent (0.25% methylcellulose) separately. The serum PRL level of PsV patients was significantly higher than that of HCs (P < 0.001). Compared with HCs, the mRNA levels of PRL and Th1/Th17 cytokines in skin lesions increased significantly (P < 0.05), and the PRL protein level was also significantly elevated in the epidermis and dermis of PsV patients. In IMQ-induced psoriasis-like mouse model, the mRNA and protein levels of PRL in skin lesions were significantly higher than CON group (P < 0.01). Comparing to solvent group, serum PRL level and PRL, cytokines mRNA levels in skin lesions all decreased significantly and the skin inflammatory condition was also alleviated obviously in anti-PRL group. This study suggests that local production of PRL is the main resource of PRL in skin lesions and may play an important role in skin inflammatory of psoriasis.

Topics: Adult; Aged; Animals; Cabergoline; Cytokines; Dermis; Disease Models, Animal; Dopamine Agonists; Epidermis; Female; Humans; Imiquimod; Male; Methylcellulose; Mice; Middle Aged; Prolactin; Psoriasis; Receptors, Prolactin; Risk Adjustment; RNA, Messenger; Solvents; TRPV Cation Channels

Oral candidiasis (OC), caused by the fungal pathogen Candida albicans, is the most common opportunistic infection in HIV(+) individuals and other immunocompromised populations. The dramatic increase in resistance to common antifungals has emphasized the importance of identifying unconventional therapeutic options. Antimicrobial peptides have emerged as promising candidates for therapeutic intervention due to their broad antimicrobial properties and lack of toxicity. Histatin-5 (Hst-5) specifically has exhibited potent anticandidal activity indicating its potential as an antifungal agent. To that end, the goal of this study was to design a biocompatible hydrogel delivery system for Hst-5 application. The bioadhesive hydroxypropyl methylcellulose (HPMC) hydrogel formulation was developed for topical oral application against OC. The new formulation was evaluated in vitro for gel viscosity, Hst-5 release rate from the gel, and killing potency and, more importantly, was tested in vivo in our mouse model of OC. The findings demonstrated a controlled sustained release of Hst-5 from the polymer and rapid killing ability. Based on viable C. albicans counts recovered from tongues of treated and untreated mice, three daily applications of the formulation beginning 1 day postinfection with C. albicans were effective in protection against development of OC. Interestingly, in some cases, Hst-5 was able to clear existing lesions as well as associated tissue inflammation. These findings were confirmed by histopathology analysis of tongue tissue. Coupled with the lack of toxicity as well as anti-inflammatory and wound-healing properties of Hst-5, the findings from this study support the progression and commercial feasibility of using this compound as a novel therapeutic agent.

Topics: Animals; Antifungal Agents; Biocompatible Materials; Candida albicans; Candidiasis, Oral; Disease Models, Animal; Drug Carriers; Drug Resistance, Fungal; Female; Histatins; Hydrogel, Polyethylene Glycol Dimethacrylate; Methylcellulose; Mice; Mice, Inbred C57BL; Microscopy, Electron, Scanning; Tongue

Transplantation of pluripotent stem cells and their differentiated progeny has the potential to preserve or regenerate functional pathways and improve function after central nervous system injury. However, their utility has been hampered by poor survival and the potential to form tumors. Peptide-modified biomaterials influence cell adhesion, survival and differentiation in vitro, but their effectiveness in vivo remains uncertain. We synthesized a peptide-modified, minimally invasive, injectable hydrogel comprised of hyaluronan and methylcellulose to enhance the survival and differentiation of human induced pluripotent stem cell-derived oligodendrocyte progenitor cells. Cells were transplanted subacutely after a moderate clip compression rat spinal cord injury. The hydrogel, modified with the RGD peptide and platelet-derived growth factor (PDGF-A), promoted early survival and integration of grafted cells. However, prolific teratoma formation was evident when cells were transplanted in media at longer survival times, indicating that either this cell line or the way in which it was cultured is unsuitable for human use. Interestingly, teratoma formation was attenuated when cells were transplanted in the hydrogel, where most cells differentiated to a glial phenotype. Thus, this hydrogel promoted cell survival and integration, and attenuated teratoma formation by promoting cell differentiation.

Topics: Animals; Behavior, Animal; Cattle; Cell Differentiation; Cell Lineage; Cell Movement; Cell Survival; Disease Models, Animal; Female; Flow Cytometry; Humans; Hyaluronic Acid; Hydrogel, Polyethylene Glycol Dimethacrylate; Induced Pluripotent Stem Cells; Injections; Methylcellulose; Oligodendroglia; Oligopeptides; Platelet-Derived Growth Factor; Rats, Sprague-Dawley; Spinal Cord Injuries; Teratoma

We attempted to develop anti-glaucoma eye drops using 0.5% disulfiram (DSF), 5% 2-hydroxypropyl-β-cyclodextrin, 0.1% hydroxypropylmethylcellulose, and 2% methylcellulose (MC) (DSF eye drops with MC), and tested the ability of a DSF eye drops with MC to reduce intraocular pressure (IOP) in rabbit models.. Elevated IOP was induced by the rapid infusion of 5% glucose solution (15 ml/kg of body weight) through the marginal ear vein or by keeping rabbits in the dark for 5 h. IOP and the nitric oxide (NO) level in the aqueous humor were measured with an electronic tonometer and by a microdialysis method, respectively. ΔIOP and ΔNO values were analyzed as the differences in IOP and NO in rabbits instilled with saline or eye drops, respectively.. Increased IOP in rabbit models was reduced by the instillation of DSF eye drops with or without MC, and a close relationship was observed between IOP and NO levels in rabbit receiving a rapid infusion of isotonic glucose. We present kinetic parameters [secondary AUC (prolonged drug effect) and secondary MRT (prolonged effective time)] analyzed as the area under the curve (AUC) of ΔIOP or ΔNO versus time using rabbits instilled with eye drops 10, 50, or 90 min prior to the infusion of the isotonic glucose solution. The elevations in IOP and NO level were reduced by the instillation of DSF eye drops with or without MC; the addition of MC increased the secondary AUC and MRT of DSF eye drops.. The present study demonstrates that 0.5% DSF eye drops suppress increased IOP in rabbit models, probably by inhibiting the elevation in NO levels. In addition, we propose a kinetic analysis method to predict drug effects and effective time. These findings suggest that a low-substituted MC-based drug delivery system promotes drug effectiveness and effective time.

Topics: 2-Hydroxypropyl-beta-cyclodextrin; Administration, Topical; Alcohol Deterrents; Animals; Aqueous Humor; beta-Cyclodextrins; Disease Models, Animal; Disulfiram; Drug Combinations; Drug Delivery Systems; Hypromellose Derivatives; Intraocular Pressure; Male; Methylcellulose; Nitric Oxide; Ophthalmic Solutions; Rabbits; Tonometry, Ocular

Cell transplantation via direct intramuscular injection is a promising therapy for patients with ischemic diseases. However, following injections, retention of transplanted cells in engrafted areas remains problematic, and can be deleterious to cell-transplantation therapy. In this Progress Report, a thermoresponsive hydrogel system composed of aqueous methylcellulose (MC) blended with phosphate-buffered saline is constructed to grow cell sheet fragments and cell bodies for the treatment of ischemic diseases. The as-prepared MC hydrogel system undergoes a sol-gel reversible transition upon heating or cooling at ≈32 °C. Via this unique property, the grown cell sheet fragments (cell bodies) can be harvested without using proteolytic enzymes; consequently, their inherent extracellular matrices (ECMs) and integrative adhesive agents remain well preserved. In animal studies using rats and pigs with experimentally created myocardial infarction, the injected cell sheet fragments (cell bodies) become entrapped in the interstices of muscular tissues and adhere to engraftment sites, while a minimal number of cells exist in the group receiving dissociated cells. Moreover, transplantation of cell sheet fragments (cell bodies) significantly increases vascular density, thereby improving the function of an infarcted heart. These experimental results demonstrate that cell sheet fragments (cell bodies) function as a cell-delivery construct by providing a favorable ECM environment to retain transplanted cells locally and consequently, improving the efficacy of therapeutic cell transplantation.

Topics: Animals; Cardiomyoplasty; Cell Hypoxia; Cell- and Tissue-Based Therapy; Disease Models, Animal; Epithelial Cells; Extracellular Matrix; Humans; Hydrogel, Polyethylene Glycol Dimethacrylate; Methylcellulose; Mice; Myocardial Infarction; Neovascularization, Physiologic; Rats; Stem Cell Transplantation; Stem Cells; Swine; Temperature

Recently, great attention has been paid to nanocapsules. The interest of these structures is due to their promising applications as drug delivery systems. The objective of this study was to develop novel enteric coating technique based on instantaneous encapsulation of the acid-labile drug, omeprazole in innovative enteric nanocapsules. Omeprazole enteric nanocapsules were formulated by varying the type and amount of the enteric polymer. The particle size (PS), polydispersity index (PDI), zeta potential (ZP) and encapsulation efficiency (EE) values of the prepared enteric nanocapsules were determined. A full 2(1)×3(1) factorial design was used for planning and analysis of the experimental trials to select the optimized formulation. The highest desirability value was 0.7463 for formula E3 (containing 200mg hydroxypropyl methylcellulose phthalate (HPMCP)). The stability of omeprazole was reflected by the absence of the exothermal peak when the drug was encapsulated as detected by differential scanning calorimetry (DSC) thermograms. In vitro drug release study confirmed the USP specifications required to meet the key formulation characteristics of gastro-resistance. In vivo pharmacological assessment showed that the optimized nanocapsules were able to protect rat stomach against ulcer formation compared to the aqueous suspension of the drug which showed less significant protection.

Topics: Animals; Anti-Ulcer Agents; Calorimetry, Differential Scanning; Chemistry, Pharmaceutical; Disease Models, Animal; Ethanol; Kinetics; Male; Methylcellulose; Microscopy, Electron, Transmission; Nanocapsules; Nanotechnology; Omeprazole; Proton Pump Inhibitors; Rats, Wistar; Solubility; Stomach Ulcer; Technology, Pharmaceutical; Thermography

To compare the efficacy of three types of ocular lubricants in protecting corneal epithelial cells in dry eye animal models.. Ocular lubricants containing 0.1% or 0.3% sodium hyaluronate (SH), carboxymethylcellulose (CMC), or hydroxypropyl methylcellulose (HPMC) were tested. First, ocular lubricant containing 0.002% fluorescein was dropped onto the rabbit corneas. The fluorescein intensity as an index of retention was measured. Second, a rabbit dry eye model was made by holding the eye open with a speculum, and 50 μL of each ocular lubricant was dropped onto the cornea. After 3 hours, the corneas were stained with 1% methylene blue (MB), and the absorbance of MB was measured. Third, a rat dry eye model was treated with the ocular lubricants for 4 weeks, and the corneal fluorescein staining was scored. Eyes treated with physiological saline were used as controls. Finally, immunohistochemistry was used to analyze occludin, an epithelial barrier protein, in cultured human corneal epithelial cells pretreated with ocular lubricants and desiccated for 20 or 60 minutes.. Our results showed that 0.3% SH had a significantly longer retention time than the other lubricants (all P < 0.01). The absorbance of MB was significantly lower in the 0.3% SH group. The corneas of rats exposed to 0.3% SH had significantly lower fluorescein staining scores. A significantly higher number of occludin-positive cells were found after exposure to 0.3% SH than other lubricants.. Ocular lubricant containing 0.3% SH would be preferable to treat patients with dry eye syndrome.

Topics: Animals; Carboxymethylcellulose Sodium; Cornea; Disease Models, Animal; Dry Eye Syndromes; Hyaluronic Acid; Hypromellose Derivatives; Male; Methylcellulose; Ophthalmic Solutions; Rabbits; Rats; Treatment Outcome; Viscosupplements

The human retina is constantly affected by light of varying intensity, this being especially true for photoreceptor cells and retinal pigment epithelium. Traditionally, photoinduced damages of the retina are induced by visible light of high intensity in albino rats using the LIRD (light-induced retinal degeneration) model. This model allows study of pathological processes in the retina and the search for retinoprotectors preventing retinal photodamage. In addition, the etiology and mechanisms of retina damage in the LIRD model have much in common with the mechanisms of the development of age-related retinal disorders, in particular, with age-related macular degeneration (AMD). We have studied preventive and therapeutic effects of Visomitin eye drops (based on the mitochondria-targeted antioxidant SkQ1) on albino rat retinas damaged by bright light. In the first series of experiments, rats receiving Visomitin for two weeks prior to illumination demonstrated significantly less expressed atrophic and degenerative changes in the retina compared to animals receiving similar drops with no SkQ1. In the second series, the illuminated rats were treated for two weeks with Visomitin or similar drops without SkQ1. The damaged retinas of the experimental animals were repaired much more effectively than those of the control animals. Therefore, we conclude that Visomitin SkQ1-containing eye drops have pronounced preventive and therapeutic effects on the photodamaged retina and might be recommended as a photoprotector and a pharmaceutical preparation for the treatment of AMD in combination with conventional medicines.

Topics: Animals; Benzalkonium Compounds; Disease Models, Animal; Drug Combinations; Female; Light; Methylcellulose; Ophthalmic Solutions; Plastoquinone; Protective Agents; Rats, Wistar; Retina; Retinal Degeneration

The present study aimed to prepare a chemically and physically stable formulation of baicalein (Ba) in an in situ thermally sensitive hydrogel for vaginal administration. An inclusion complex of Ba and hydroxypropyl-γ-cyclodextrin (HP-γ-CD) was first developed to increase the stability and solubility of Ba in an aqueous solution. The formation of the Ba-HP-γ-CD complex was characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and X-ray powder diffractometry (XRPD). Poloxamers 407, 188 (P407, P188), sodium alginate (SA), hydroxypropylmethylcellulose (HPMC), and benzalkonium bromide were mixed to obtain a hydrogel with an appropriate gelation temperature for vaginal use. Among the formulations examined, P407/Ba-HP-γ-CD/HPMC/P188/benzalkonium bromide (18/0.96/0.5/4.0/0.02%) represented the appropriate gelation temperature and acceptable drug release rate at the administration site. Release of Ba-HP-γ-CD from the poloxamer hydrogel followed Peppas equation, which suggests that it occurred through coupled corrosion-diffusion mechanism, and the corrosion-release curve showed that corrosion was the primary mode of release. In animal study, treatment by using Ba-HP-γ-CD thermosensitive hydrogel could produce a restoration of damaged tissues. Thermosensitive hydrogel formulation of the Ba-HP-γ-CD complex appears to be a promising treatment for cervicitis.

Topics: Administration, Intravaginal; Alginates; Animals; Anti-Inflammatory Agents; Benzalkonium Compounds; Bromides; Calorimetry, Differential Scanning; Chemistry, Pharmaceutical; Disease Models, Animal; Drug Carriers; Drug Stability; Female; Flavanones; gamma-Cyclodextrins; Glucuronic Acid; Hexuronic Acids; Humans; Hydrogels; Hypromellose Derivatives; Kinetics; Methylcellulose; Microscopy, Electron, Scanning; Poloxamer; Powder Diffraction; Rats, Sprague-Dawley; Solubility; Technology, Pharmaceutical; Temperature; Uterine Cervicitis; X-Ray Diffraction

The proximity of cells in three-dimensional (3D) organization maximizes the cell-cell communication and signaling that are critical for cell function. In this study, 3D cell aggregates composed of human umbilical vein endothelial cells (HUVECs) and cord-blood mesenchymal stem cells (cbMSCs) were used for therapeutic neovascularization to rescue tissues from critical limb ischemia. Within the cell aggregates, homogeneously mixed HUVECs and cbMSCs had direct cell-cell contact with expressions of endogenous extracellular matrices and adhesion molecules. Although dissociated HUVECs/cbMSCs initially formed tubular structures on Matrigel, the grown tubular network substantially regressed over time. Conversely, 3D HUVEC/cbMSC aggregates seeded on Matrigel exhibited an extensive tubular network that continued to expand without regression. Immunostaining experiments show that, by differentiating into smooth muscle cell (SMC) lineages, the cbMSCs stabilize the HUVEC-derived tubular network. The real-time PCR analysis results suggest that, through myocardin, TGF-β signaling regulates the differentiation of cbMSCs into SMCs. Transplantation of 3D HUVEC/cbMSC aggregates recovered blood perfusion in a mouse model of hindlimb ischemia more effectively compared to their dissociated counterparts. The experimental results confirm that the transplanted 3D HUVEC/cbMSC aggregates enhanced functional vessel formation within the ischemic limb and protected it from degeneration. The 3D HUVEC/cbMSC aggregates can therefore facilitate the cell-based therapeutic strategies for modulating postnatal neovascularization.

Topics: Animals; Cell Aggregation; Collagen; Disease Models, Animal; Drug Combinations; Fetal Blood; Fluorescent Antibody Technique; Gene Expression Regulation; Hindlimb; Human Umbilical Vein Endothelial Cells; Humans; Ischemia; Laminin; Limb Salvage; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Methylcellulose; Mice; Mice, Inbred BALB C; Neovascularization, Physiologic; Perfusion; Proteoglycans

Systemic sclerosis (SSc) is a connective tissue disease characterized by vasculopathy, excessive accumulation of extracellular matrix, and fibrosis of the skin and internal organs. An animal model of SSc, the bleomycin-induced mouse model, has been established and used extensively to investigate the pathogenesis of SSc and to seek novel therapeutic agents. We recently developed thermo-reversible combination gels that can be injected subcutaneously and are made in aqueous solution by forming a complex coacervate with the substance of interest and cationic macromolecules, followed by co-formulation with methylcellulose (MC) as a negative thermosensitive polysaccharide. The objective of this study was to demonstrate whether weekly injections of bleomycin using combination gels loaded with bleomycin can induce the skin fibrosis model of SSc in susceptible mouse strains. A low molecular weight MC (4%) gel with 4.5% ammonium sulfate was made in aqueous solution, and mixed with bleomycin. This was injected subcutaneously into female C3H/He mice at weekly intervals. Control mice were injected with the gel made with phosphate-buffered saline. After 4 weeks, histological examination and gene expression assays of cytokines were performed. Examination in vitro showed that more than 80% of the bleomycin was released from the gel by the 4th day. Histological examination showed that dermal thickness increased in the MC-bleomycin-injected group compared with the control, and semi-quantitative analysis indicated that the extent of inflammation did not differ between the groups. In the MC-bleomycin-injected group, dermal fibrosis assessed with the Masson-Trichrome stain and numbers of alpha-smooth muscle actin-positive fibroblastic cells also increased. The procedure for inducing scleroderma in which bleomycin is injected weekly as an easily-made gel system using methylcellulose, can induce dermal fibrosis in susceptible mice without causing inflammation. We believe this system represents a time- saving and convenient procedure that should facilitate research on SSc.

Topics: Actins; Animals; Bleomycin; Cytokines; Disease Models, Animal; Drug Carriers; Female; Fibroblasts; Fibrosis; Gels; Gene Expression Regulation; Injections, Subcutaneous; Methylcellulose; Mice; Mice, Inbred C3H; Scleroderma, Systemic; Skin; Time Factors; Transforming Growth Factor beta1

Preparation of coated pellets intended for rutin colon delivery, their evaluation in vitro and in vivo in experimental colitis in rats was the purpose of this study. Pellets were obtained using extrusion/spheronization and coated with three types of coatings (caffeic acid/hypromellose/alginic acid; sodium alginate/hypromellose/zinc acetate; sodium alginate/chitosan). Dissolution using buffers of pH values, β-glucosidase and times corresponding to gastrointestinal tract (GIT) was provided. Pellets coated with alginate/chitosan showed low rutin dissolution (12-14%) in upper GIT conditions and fast release (87-89%) under colon conditions; that is a good presumption of intended rutin release. After colitis induction and development, the rats were treated with pellets and rutin solution administered orally, solution also rectally. Colon/body weight ratio, myeloperoxidase activity and histological evaluation were performed. Rutin was able to promote colonic healing at the dose of 10mg/kg: colon/body weight ratio decreased and myeloperoxidase activity was significantly suppressed. Pellets coated with alginate/chitosan applied orally and rutin solution administered rectally showed the best efficacy. The combination of rutin as natural product, mucoadhesive chitosan degraded in the colon and sodium alginate as the main coating substance in the form of pellets create a promising preparation for therapy of this severe illness.

Topics: Administration, Oral; Alginates; Animals; Anti-Inflammatory Agents; Buffers; Caffeic Acids; Chemistry, Pharmaceutical; Chitosan; Colitis; Colon; Disease Models, Animal; Drug Compounding; Drug Implants; Drug Stability; Gastrointestinal Agents; Glucuronic Acid; Hexuronic Acids; Hydrogen-Ion Concentration; Hypromellose Derivatives; Male; Methylcellulose; Rats; Rats, Wistar; Rutin; Solubility; Technology, Pharmaceutical; Time Factors; Trinitrobenzenesulfonic Acid; Zinc Acetate

The aim of this study was to develop an effective drug delivery system for the simultaneous topical delivery of two anti-inflammatory drugs, spantide II (SP) and ketoprofen (KP). To achieve this primary goal, we have developed a skin permeating nanogel system (SPN) containing surface modified polymeric bilayered nanoparticles along with a gelling agent. Poly-(lactide-co-glycolic acid) and chitosan were used to prepare bilayered nanoparticles (NPS) and the surface was modified with oleic acid (NPSO). Hydroxypropyl methyl cellulose (HPMC) and Carbopol with the desired viscosity were utilized to prepare the nanogels. The nanogel system was further investigated for in vitro skin permeation, drug release and stability studies. Allergic contact dermatitis (ACD) and psoriatic plaque like model were used to assess the effectiveness of SPN. Dispersion of NPSO in HPMC (SPN) produced a stable and uniform dispersion. In vitro permeation studies revealed increase in deposition of SP for the SP-SPN or SP+KP-SPN in the epidermis and dermis by 8.5 and 9.5 folds, respectively than SP-gel. Further, the deposition of KP for KP-SPN or SP+KP-SPN in epidermis and dermis was 9.75 and 11.55 folds higher, respectively than KP-gel. Similarly the amount of KP permeated for KP-SPN or SP+KP-SPN was increased by 9.92 folds than KP-gel. The ear thickness in ACD model and the expression of IL-17 and IL-23; PASI score and TEWL values in psoriatic plaque like model were significantly less (p < 0.001) for SPN compared to control gel. Our results suggest that SP+KP-SPN have significant potential for the percutaneous delivery of SP and KP to the deeper skin layers for treatment of various skin inflammatory disorders.

Topics: Administration, Cutaneous; Aminoquinolines; Animals; Anti-Inflammatory Agents; Disease Models, Animal; Drug Delivery Systems; Humans; Hypromellose Derivatives; Imiquimod; Immunohistochemistry; Inflammation; Methylcellulose; Mice; Mice, Inbred C57BL; Nanogels; Nanoparticles; Particle Size; Permeability; Polyethylene Glycols; Polyethyleneimine; Psoriasis; Rheology; Skin; Surface Properties; Viscosity

We attempted to develop anti-cataract eye drops using disulfiram (DSF) and low-substituted methylcellulose (MC), and evaluated their anti-cataract effect in terms of the lens opacification vs. age-profile curves using a one-exponential equation. The eye drops were prepared using 0.5% DSF and 2% MC (DSF eye drops), and ICR/f rats, a recessive-type hereditary cataractous strain, were used as the experimental model. Gelation of DSF eye drops containing MC was first observed at about 35°C, close to body temperature. In in vivo transcorneal penetration experiments using rabbit corneas, only diethyldithiocarbamate (DDC) was detected in the aqueous humor, while DSF was not detected. The DDC penetration level of DSF eye drops containing MC was approximately 1.3-fold higher than that of DSF eye drops. The opacification rate constant (k) of ICR/f rat instilled with DSF eye drops with or without MC was lower, and the initial time of opacification (τ) was longer than those of ICR/f rats instilled with saline. Furthermore, the k of ICR/f rats instilled with DSF eye drops with MC was lower than that of ICR/f rats instilled with DSF eye drops without MC. In conclusion, the analysis of kinetic parameters including k and τ using a one-exponential equation provided useful information for clarifying the anti-cataract effect of eye drops. ICR/f rats instilled with DSF eye drops using a low-substituted MC-based drug delivery system demonstrated a delay in cataract development, probably resulting from an increase in the retention of DSF eye drops on the cornea.

Topics: Animals; Antioxidants; Cataract; Disease Models, Animal; Disulfiram; Drug Carriers; Hypromellose Derivatives; Male; Methylcellulose; Ophthalmic Solutions; Rabbits; Rats

A major hurdle for hematopoietic stem cell (HSC) gene therapy for inherited bone marrow disorders, including Fanconi anemia (FA), is adequate engraftment of gene-modified cells. A phenotypic defect in DNA repair renders FA patients sensitive to alkylating agents such as cyclophosphamide (Cy); however, at lower doses, Cy is well tolerated in the FA transplant setting. We tested whether non-alkylating agents could replace Cy for pretransplant conditioning to enhance engraftment of FANCA gene-modified hematopoietic cells. We compared Cy preconditioning with fludarabine (Flu) or cytarabine (AraC) or no conditioning as a control in fanca ( -/- ) mutant mice receiving gene-modified bone marrow cells. Only mice conditioned with Cy exhibited appreciable engraftment of gene-modified cells by PCR and resistance to mitomycin C (MMC). Cy administration following transplantation increased gene marking levels in all animals treated, but highest gene marking and corresponding MMC resistance were observed in mice receiving Cy pre- and posttransplantation. Importantly, no cytogenetic abnormalities were observed in Cy-treated mice. We conclude that Cy is an effective and superior preparative regimen with respect to engraftment of lentivirus-transduced cells and functional correction in fanca ( -/- ) mice. Thus, appropriately dosed Cy may provide a suitable conditioning regimen for FA patients undergoing HSC gene therapy.

Topics: Animals; Bone Marrow Cells; Cyclophosphamide; Cytogenetics; Disease Models, Animal; Fanconi Anemia; Flow Cytometry; Genetic Therapy; HEK293 Cells; Hematopoietic Stem Cell Transplantation; Humans; Lentivirus; Methylcellulose; Mice; Mice, Transgenic; Mitomycin; Myeloablative Agonists; Polymerase Chain Reaction; Transplantation Conditioning

Benzalkonium chloride (BAC) is known to cause corneal epithelial damage. In this study we investigated the effect of a BAC solution containing a thickening agent, which enhanced residence time in the eyes, on corneal wound healing using in vivo rat model debrided corneal epithelium. 0.5% or 1.0% methylcellulose (MC), carboxymethylcellulose (CMC) and hydroxypropyl-methylcellulose (HPMC) were used as the thickening agent. The levels of corneal wound healing of rat eyes injected with saline were alone approximately 45.0% at 12 h and 93.6% at 24 h after corneal epithelial abrasion, and healing was almost complete at 36 h. The healing rate in the rat eye treated just with MC, CMC and HPMC was higher than that in those injected with saline. In contrast to the treatment result using only this thickening agent, the healing rate in the eye treated with BAC was lower than that in those injected with saline: the corneal wounds in the BAC-treated eye showed approximately 20% healing at 12 h after abrasion. The injection of 0.02% BAC solution containing MC, CMC and HPMC more significantly delayed the healing than did the injection of 0.02% BAC alone. The results show that the in vivo evaluation method for corneal damage using rat debrided corneal epithelium reflects a toxic change depending upon residence time. These findings provide valuable safety and efficacy information for use in the design of eye drops.

Topics: Adjuvants, Pharmaceutic; Animals; Benzalkonium Compounds; Carboxymethylcellulose Sodium; Cells, Cultured; Disease Models, Animal; Drug Design; Epithelium, Corneal; Humans; Hypromellose Derivatives; Methylcellulose; Ophthalmic Solutions; Preservatives, Pharmaceutical; Rats; Rats, Wistar; Solutions; Time Factors; Wound Healing

Structural and functional abnormalities in the neurovascular unit (NVU) have been recently observed in Alzheimer's disease (AD). Statins, which are used clinically for reducing cholesterol levels, can also exert beneficial vascular actions, improve behavioral memory and reduce senile plaque (SP). Thus, we examined cognitive function, the serum level of lipids, senile plaque (SP), and the protective effects of statins on NVU disturbances in a mouse AD model. Amyloid precursor protein (APP) transgenic (Tg) mice were used as a model of AD. Atorvastatin (30 mg/kg/day, p.o.) or pitavastatin (3mg/kg/day, p.o.) were administered from 5 to 20 months of age. These 2 statins improved behavioral memory and reduced the numbers of SP at 15 and 20 M without affecting serum lipid levels. There was a reduction in immunopositive staining for N-acetyl glucosamine oligomer (NAGO) in the endothelium and in collagen IV in the APP vehicle (APP/Ve) group, with collagen IV staining most weakest near SP. There was also an increase in intensity and numbers of glial fibrillary acidic protein (GFAP) positive astrocytes, particularly around the SP, where MMP-9 was more strongly labeled. Double immunofluorescent analysis showed that astrocytic endfeet had detached from the capillary endothelium in the APP/Ve group. Overall, these data suggest that statins may have therapeutic potential for AD by protecting NVU.

Topics: Age Factors; Alzheimer Disease; Amyloid beta-Peptides; Amyloid beta-Protein Precursor; Analysis of Variance; Animals; Anticholesteremic Agents; Atorvastatin; Cholesterol; Collagen Type IV; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Glial Fibrillary Acidic Protein; Glucosamine; Heptanoic Acids; Humans; Matrix Metalloproteinase 9; Maze Learning; Methylcellulose; Mice; Mice, Transgenic; Mutation; Pyrroles; Quinolines

A common strategy for the prevention of intra-abdominal adhesions post-operatively has been the application of adhesion barriers into the peritoneal cavity. Side effects of these barriers are infection, abscesses and inadequate wound healing. There is no information about such a side effect of these materials on renal function. The aim of this study was to evaluate the effect of two different, commercially available polysaccharide-based anti-adhesive materials on renal function.. In 24 adult Wistar rats, an abdominal midline incision was performed, and an anti-adhesion membrane was placed in the peritoneal cavity so as to cover its whole surface. Four rats were used as the control group. In 12 rats, a membrane of macromolecular polysaccharides, weighing 40 mg/cm2, was placed intra-abdominally and in 8 rats, a hyaluronic acid-hydroacidmethylcellulose membrane weighing 0.4 mg/cm2 was placed. At 24 or 70 h, the rats were sacrificed, and we evaluated changes in serum creatinine, urea, uric acid, K and Na, and histologic examination of the kidney was performed.. The use of the thicker macromolecular membrane was associated with a rise in serum creatinine and urea levels, vacuolization of all the tubular epithelial cells and mild interstitial infiltration. Rats in which the hyaluronic acid-hydroacidmethylcellulose membrane was used did not show any creatinine elevation, and they presented milder histologic lesions.. Polysaccharide and cellulose anti-adhesive membrane cause renal damage with tubular cell vacuolization. The severity of kidney damage is relative to the quantity of the membrane material used.

Topics: Animals; Biocompatible Materials; Biopsy; Disease Models, Animal; Hyaluronic Acid; Kidney; Membranes, Artificial; Methylcellulose; Nephrosis; Peritoneum; Polysaccharides; Rats; Rats, Wistar; Tissue Adhesions

Benznidazole (BNZ) is traditionally used to treat Chagas disease. Despite its common use, BNZ has a poor water solubility and a variable bioavailability. The purpose of this study was to prepare BNZ microcrystals by solvent change precipitation and to study the effects of BNZ micronisation on therapeutic efficiency using a murine model of Chagas disease. The solvent change precipitation procedure was optimised in order to obtain stable and homogeneous particles with a small particle size, high yield and fast dissolution rate. The thermal and crystallographic analysis showed no polymorphic change in the microcrystals, and microscopy confirmed a significant reduction in particle size. A marked improvement in the drug dissolution rate was observed for micronised BNZ particles and BNZ tablets in comparison with untreated BNZ and commercial Rochagan. In vivo studies showed a significant increase in the therapeutic efficacy of the BNZ microparticles, corroborating the dissolution results.

Topics: Animals; Chagas Disease; Chemical Precipitation; Disease Models, Animal; Drug Compounding; Drug Delivery Systems; Excipients; Female; Hardness Tests; Hypromellose Derivatives; Methylcellulose; Mice; Nitroimidazoles; Polymers; Solubility; Solvents; Tablets; Trypanocidal Agents; Trypanosoma cruzi

We examined the therapeutic effects of cinnamaldehyde and the potentiation of those effects with cassia and cinnamaldehyde when combined with the food additive methylcellulose against murine oral candidiasis. When 19.5mg/ml of cinnamaldehyde was administered in the oral cavity of Candida infected mice, the oral symptoms were improved. Furthermore, when either a cassia or a cinnamaldehyde preparation in combination with methylcellulose was administered to oral candidiasis-inflicted mice, the therapeutic effects of cassia or cinnamaldehyde potentiated. Methylcellulose itself did not affect the oral symptoms or the viable number of C. albicans cells. GC/MS analysis showed that the dose of cinnamaldehyde remaining in the tongue tissue of mice treated with the cinnamaldehyde-methylcellulose mixture was higher than that in mice administered cinnamaldehyde alone, and also showed that cinnamaldehyde was not detected in the blood of any of the tested mice. These findings suggested that the combination of cassia or cinnamaldehyde and methylcellulose may be a useful prophylactic or therapeutic tool against oral candidiasis.

Topics: Acrolein; Administration, Oral; Animals; Candidiasis, Oral; Cassia; Disease Models, Animal; Drug Synergism; Female; Methylcellulose; Mice; Mice, Inbred ICR; Plant Preparations

The authors investigated the feasibility of using injectable hydrogels, based on poly(N-isopropylacrylamide) (PNIPAAm), lightly cross-linked with polyethylene glycol (PEG) or methylcellulose (MC), to serve as injectable scaffolds for local delivery of neurotrophins and cellular transplants into the injured spinal cord. The primary aims of this work were to assess the biocompatibility of the scaffolds by evaluating graft cell survival and the host tissue immune response. The scaffolds were also evaluated for their ability to promote axonal growth through the action of released brain-derived neurotrophic factor (BDNF).. The in vivo performance of PNIPAAm-g-PEG and PNIPAAm-g-MC was evaluated using a rodent model of spinal cord injury (SCI). The hydrogels were injected as viscous liquids into the injury site and formed space-filling hydrogels. The host immune response and biocompatibility of the scaffolds were evaluated at 2 weeks by histological and fluorescent immunohistochemical analysis. Commercially available matrices were used as a control and examined for comparison.. Experiments showed that the scaffolds did not contribute to an injury-related inflammatory response. PNIPAAm-g-PEG was also shown to be an effective vehicle for delivery of cellular transplants and supported graft survival. Additionally, PNIPAAm-g-PEG and PNIPAAm-g-MC are permissive to axonal growth and can serve as injectable scaffolds for local delivery of BDNF.. Based on the results, the authors suggest that these copolymers are feasible injectable scaffolds for cell grafting into the injured spinal cord and for delivery of therapeutic factors.

Topics: Acrylamides; Acrylic Resins; Animals; Axons; Brain-Derived Neurotrophic Factor; Cell Transplantation; Cicatrix; Disease Models, Animal; Drug Delivery Systems; Female; Graft Survival; Hydrogels; Injections, Intralesional; Methylcellulose; Nerve Regeneration; Neuroglia; Pilot Projects; Polyethylene Glycols; Polymers; Rats; Rats, Sprague-Dawley; Spinal Cord Injuries; Tissue Scaffolds

The bioavailability of therapeutic agents from eye drops is usually limited due to corneal barrier functions and effective eye protective mechanisms. Therefore, the current study aims to enhance ocular bioavailability of brimonidine, a potent antiglaucoma drug, through the preparation of ocular inserts. Solvent casting technique was employed to prepare the inserts using polyvinylpyrrolidone K-90 (PVP K-90) as film-forming polymer blended with different viscosity grades of bioadhesive polymers namely hydroxypropyl methycellulose, carbopol, sodium alginate, and chitosan. The prepared ocular inserts were evaluated for various physicochemical parameters, swelling behavior, and in vitro release patterns. Sodium alginate-based ocular inserts revealed the most sustainment in drug release (99% at 6 h), so it was selected for further modifications via coating it, on one side or dual sides, using hydrophobic film composed of either ethylcellulose or Eudragit RSPO. The obtained in vitro release results for the modified ocular inserts revealed that ethylcellulose is superior to Eudragit RSPO in terms of brimonidine release sustainment effect. Ocular inserts composed of 7% PVP K-90, 1.5% low molecular weight sodium alginate with or without ethylcellulose coat were able to sustain the in vitro release of brimonidine. Their therapeutic efficacy regarding intraocular pressure (IOP) lowering effect when inserted in albino rabbits eyes showed superior sustainment effect compared with that of brimonidine solution. Furthermore, due to both the mucoadhesive property and the drug sustainment effect, the one-side-coated ocular insert showed more IOP lowering effect compared with that of its non-coated or dual-side-coated counterpart.

Topics: Absorbable Implants; Acrylic Resins; Administration, Ophthalmic; Adrenergic alpha-2 Receptor Agonists; Alginates; Animals; Brimonidine Tartrate; Calorimetry, Differential Scanning; Cellulose; Chemistry, Pharmaceutical; Chitosan; Delayed-Action Preparations; Disease Models, Animal; Drug Carriers; Drug Compounding; Glaucoma; Glucuronic Acid; Hexuronic Acids; Hydrophobic and Hydrophilic Interactions; Hypromellose Derivatives; Intraocular Pressure; Kinetics; Methylcellulose; Ophthalmic Solutions; Polymers; Polymethacrylic Acids; Polyvinyls; Povidone; Quinoxalines; Rabbits; Solubility; Spectroscopy, Fourier Transform Infrared; Technology, Pharmaceutical; X-Ray Diffraction

To characterise the magnitude and distribution of fibroblast growth factor-2 (FGF-2) following topical application in hypromellose gel and film formulations or a solution in an animal wound model, in order to assess the potential of this route for treatment of chronic wounds.. Topical formulations of FGF-2 were applied to punch biopsy wounds, and FGF-2 levels within the wound measured. Each 12 mm diameter wound received 0.3 microg FGF-2 in solution, a 7% (w/w) hypromellose gel, a dried hypromellose film on Melolin-backing or a saline control. After 2, 5 or 8 h the wounds were horizontally dissected into four sections (surface granulation, subcutaneous fat, superficial muscle and deep muscle) which were then analysed for FGF-2 concentration using ELISA. Confocal microscopy was used to evaluate the distribution of FGF-2 within the wound.. There were significant differences in the mean FGF-2 levels with respect to formulation and time following application (P < 0.05). FGF-2 penetrated faster into tissue when formulated as a solution than as a gel or a film. There did not appear to be a significant difference between the gel and the film with respect to total concentrations achieved in the tissue, although confocal microscopy showed differences in FGF-2 distribution within the wound.. Delivery of FGF-2 to wounds in a solution gave the greatest increase in tissue FGF-2 concentration when measured by ELISA and visualised using confocal microscopy. Gel and film formulations prolonged the release of FGF-2 into the wound, although FGF-2 levels were not significantly different from controls when measured by ELISA. Confocal microscopy highlighted the differences in the penetration and distribution of the FGF-2 within the wound when released from different formulations.

Topics: Administration, Topical; Animals; Chemistry, Pharmaceutical; Disease Models, Animal; Drug Delivery Systems; Enzyme-Linked Immunosorbent Assay; Female; Fibroblast Growth Factor 2; Fluorescence; Gels; Hypromellose Derivatives; Male; Methylcellulose; Microscopy, Confocal; Rats; Rats, Inbred Lew; Recombinant Proteins; Skin; Solutions; Time Factors; Wound Healing

The purpose of this study was to formulate budesonide (BUD) compression-coated tablets for colonic specific delivery. Pectin and guar gum were used as enzyme-dependent polymers. For comparison purposes, both pH- and time-dependent polymers were also tried. In vitro release studies were carried out at different pH (1.2, 6.8, and 7.4). Therapeutic efficacy of the prepared tablets compared to commercially available capsules and enema were evaluated in trinitrobenzenesulfonic acid-induced rabbit colitis model. In pH-dependent polymers, Eudragit (EUD) S100/EUD L100 (1:1) released 45.58% in the target area (colon). For time-dependent polymers, decreasing cellulose acetate butyrate (CAB) ratio increased the release in both pH 6.8 and 7.4 till it reached 40.58% and 93.65%, respectively, for 25% CAB. In enzyme-dependent polymers, increasing pectin ratio to 75% retarded the release (4.59% in pH 6.8 and 54.45% in pH 7.4) which was significantly enhanced to 99.31% using pectinolytic enzyme. Formula F14 coated with 75% pectin significantly reduced the inflammatory cells in the connective tissue core of the colon of the treated group and significantly decreased myeloperoxidase activity (3.90 U/g tissue weight). This study proved that BUD compression-coated with 75% pectin may be beneficial in the treatment of inflammatory bowel disease.

Topics: Administration, Oral; Animals; Anti-Inflammatory Agents; Budesonide; Calorimetry, Differential Scanning; Cellulose; Chemistry, Pharmaceutical; Colitis; Colon; Delayed-Action Preparations; Disease Models, Animal; Drug Carriers; Drug Compounding; Galactans; Gastrointestinal Agents; Hydrogen-Ion Concentration; Hypromellose Derivatives; Kinetics; Male; Mannans; Methylcellulose; Pectins; Plant Gums; Polymethacrylic Acids; Rabbits; Rheology; Solubility; Tablets, Enteric-Coated; Technology, Pharmaceutical; Trinitrobenzenesulfonic Acid

This project aims to investigate the anti-inflammatory properties of mastic [(Pistacia lentiscus var. Chia (Anacardiaceae)] extracted from the Chios mastic plant to help reduce intestinal inflammation in inflammatory bowel disease patients. Mastic and mastic resin were obtained from the Chios Mastiha Growers Association (www.mastihashop.com). The resin was ground into a fine powder using a pestle and mortar and formulated in factorial design manner. Evaluation of the efficacy of specific anti-inflammatory/antioxidant compounds in mitigating the clinical colitis parameters in a mouse model of colitis were performed with mastic itself and combination of tocopherol compounds. Colonic drug delivery system was developed consisting of two compartment model and its release profile was also investigated.

Topics: alpha-Tocopherol; Animals; Anti-Inflammatory Agents; Antioxidants; Chemistry, Pharmaceutical; Colitis; Dextran Sulfate; Disease Models, Animal; Dosage Forms; Drug Carriers; Drug Therapy, Combination; Gastrointestinal Agents; Hydrogen-Ion Concentration; Hypromellose Derivatives; Kinetics; Male; Methylcellulose; Mice; Mice, Inbred C57BL; Pectins; Pistacia; Resins, Plant; Solubility

The purpose of this study was to develop poloxamer-based in situ gelling formulations of ciprofloxacin hydrochloride (HCl) aiming at prolonging corneal contact time, controlling drug release, enhancing ocular bioavailability, and increasing patient compliance. The in situ forming gels were prepared using different concentrations of poloxamer 407 (P407) and poloxamer 188 (P188). Mucoadhesives such as hydroxypropylmethyl cellulose (HPMC) or hydroxyethyl cellulose (HEC) were added to the formulations to enhance the gel bioadhesion properties. The prepared formulations were evaluated for their in vitro drug release, sol-gel transition temperature, rheological behavior, and mucoadhesion force. The in vivo antimicrobial efficacy of selected ciprofloxacin HCl in situ gelling formulations was studied on infected rabbit's eyes and compared with that of the marketed conventional eye drops. The gelation temperature of the prepared formulations ranged from 28.00 to 34.03 degrees C. Increasing the concentrations of P407, HPMC, and HEC increased the viscosity and mucoadhesion force of the preparations and decreased the in vitro drug release. Ciprofloxacin HCl in situ forming gel formulae composed of P407/P188/HPMC (18/13/1.5%, wt/wt), and P407/P188/HEC (18/13/0.5%, wt/wt) showed optimum release and mucoadhesion properties and improved ocular bioavailability as evidenced by an enhanced therapeutic response compared with the marketed conventional eye drops.

Topics: Adhesiveness; Animals; Anti-Infective Agents; Biological Availability; Cellulose; Ciprofloxacin; Conjunctivitis, Bacterial; Delayed-Action Preparations; Disease Models, Animal; Excipients; Gels; Hypromellose Derivatives; Methylcellulose; Patient Compliance; Poloxamer; Rabbits; Rheology; Transition Temperature; Viscosity

Captopril granules of controlled release with different polymers as ethylcellulose, ethyl/methylcellulose, and immediate release with polyvinylpyrrolidone (PVP) were developed by fluid bed dryer technique. The formulations were analyzed by scanning electron microscopy, X-ray powder diffraction, and dissolution profiles. To compare the formulations an in vivo setting rat blood pressure assay was performed, using angiotensin I as a vasoconstrictor agent. The scanning electron microscopy of granules showed differences in morphology, and X-ray powder diffraction technique presented some modification in crystalline structure of captopril in granules coated with PVP and ethyl/methylcellulose. The dissolution profile of granules coated with ethylcellulose showed a median time release of 4 hr whereas for granules coated with ethyl/methylcellulose, this time was 3.5 hr. The blockage of angiotensin I-induced hypertensive effect lasted 8 hr in granules coated with PVP and of more than 12 hr in the granules coated with ethylcellulose and ethyl/methylcellulose.

Topics: Administration, Oral; Angiotensin I; Angiotensin-Converting Enzyme Inhibitors; Animals; Antihypertensive Agents; Blood Pressure; Captopril; Cellulose; Chemistry, Pharmaceutical; Crystallography, X-Ray; Delayed-Action Preparations; Disease Models, Animal; Drug Compounding; Female; Hypertension; Kinetics; Methylcellulose; Microscopy, Electron, Scanning; Models, Chemical; Povidone; Powder Diffraction; Powders; Rats; Rats, Wistar; Solubility; Technology, Pharmaceutical

The frontal leaves of Tectona grandis (Verabinaceae) are widely used in the folklore for the treatment of various kinds of wounds, especially burn wound. The present study was carried out to evaluate the effect of hydrochloric extract of Tectona grandis on experimentally induced wounds in rats and compare the effects observed with a known wound healing agent, Aloe vera. The models selected were excision wound, incision wound, burn wound and dead space wound. A suitable gel formulation was selected for the application using cellophane membrane penetration. In the excision wound and burn wound models, animals treated with Tectona grandis leaf extract showed significant reduction in period of epithelisation and wound contraction 50%. In the incision wound model, a significant increase in the breaking strength was observed. Tectona grandis leaf extract treatment orally produced a significant increase in the breaking strength, dry weight and hydroxyproline content of the granulation tissue in dead space wound. It was concluded that Tectona grandis leaf extract applied topically (5% and 10% gel formulation) or administered orally (250 mg and 500 mg/kg body weight) possesses wound healing activity.

Topics: Administration, Oral; Administration, Topical; Aloe; Animals; Burns; Chemistry, Pharmaceutical; Dermatologic Surgical Procedures; Disease Models, Animal; Drug Carriers; Drug Compounding; Gels; Granulation Tissue; Hot Temperature; Hydrochloric Acid; Hydroxyproline; Hypromellose Derivatives; Male; Methylcellulose; Plant Extracts; Plant Leaves; Rats; Rats, Wistar; Skin; Solvents; Verbenaceae; Wound Healing; Wounds, Penetrating

Stem cell transplantation is a promising approach for the treatment of traumatic brain injury, although the therapeutic benefits are limited by a high degree of donor cell death. Tissue engineering is a strategy to improve donor cell survival by providing structural and adhesive support. However, optimization prior to clinical implementation requires expensive and time-consuming in vivo studies. Accordingly, we have developed a three-dimensional (3-D) in vitro model of the injured host-transplant interface that can be used as a test bed for high-throughput evaluation of tissue-engineered strategies. The neuronal-astrocytic cocultures in 3-D were subjected to mechanical loading (inducing cell death and specific astrogliotic alterations) or to treatment with transforming growth factor-beta1 (TGF-beta1), inducing astrogliosis without affecting viability. Neural stem cells (NSCs) were then delivered to the cocultures. A sharp increase in the number of TUNEL(+) donor cells was observed in the injured cocultures compared to that in the TGF-beta1-treated and control cocultures, suggesting that factors related to mechanical injury, but not strictly astrogliosis, were detrimental to donor cell survival. We then utilized the mechanically injured cocultures to evaluate a methylcellulose-laminin (MC-LN) scaffold designed to reduce apoptosis. When NSCs were co-delivered with MC alone or MC-LN to the injured cocultures, the number of caspase(+) donor cells significantly decreased compared to that with vehicle delivery (medium). Collectively, these results demonstrate the utility of an in vitro model as a pre-animal test bed and support further investigation of a tissue-engineering approach for chaperoned NSC delivery targeted to improve donor cell survival in neural transplantation.

Topics: Animals; Animals, Newborn; Apoptosis; Astrocytes; Cell Death; Cell Survival; Cells, Cultured; Coculture Techniques; Disease Models, Animal; Female; Graft Survival; In Situ Nick-End Labeling; Laminin; Methylcellulose; Neurons; Organ Culture Techniques; Rats; Stem Cell Transplantation; Stem Cells; Stress, Mechanical; Tissue Engineering; Transforming Growth Factor beta1

Glaucoma is a chronic and progressive optic nerve neuropathy involving the death of retinal ganglion cells (RGCs). Elevated intraocular pressure (IOP) is considered to be the major risk factor associated with the development of this neuropathy. The objective of the present study was to compare the effects on RGC survival of three different experimental methods to induce chronic elevation of IOP in rats. These methods were: (i) injections of latex microspheres into the eye anterior chamber; (ii) injections into the anterior chamber of a mixture of microspheres plus hydroxypropylmethylcellulose (HPM) and (iii) cauterization of three episcleral veins. The IOP of right (control) and left (glaucomatous) eyes was measured with an applanation tonometer in awake animals. Thirteen to 30 weeks later, RGCs were retrogradely labeled with 3% fluorogold. Subsequently, we analyzed the density of RGCs, as well as the major axis length and area of RGC soma resulting from the application of each method. A significant increase in IOP was found following application of each of the three methods. Cell death was evident in the glaucomatous eyes as compared to controls. However, no statistical differences were found between the extent of cell death associated with each of the three methods. IOP increase also induced a significant increase in the size of the soma of the remaining RGCs. In conclusion, the three methods used to increase IOP induce a similar degree of RGC death. Moreover, the extent of cell death was similar when the retinas were maintained under conditions of elevated IOP for 24 weeks in comparison to 13 weeks.

Topics: Animals; Anterior Chamber; Cautery; Cell Count; Cell Death; Cell Size; Cell Survival; Disease Models, Animal; Female; Glaucoma; Hypromellose Derivatives; Injections; Intraocular Pressure; Latex; Methylcellulose; Microspheres; Ophthalmic Solutions; Rats; Rats, Sprague-Dawley; Retinal Ganglion Cells; Sclera; Veins

The use of injectable biomaterials is of interest in osteoporotic patients to locally restore bone mass in sites at risk of fracture. An injectable bone substitute (IBS1 made of betaTCP/hydroxyapatite as a calcium phosphate substitute and hydroxy-propyl-methyl-cellulose as a polymer carrier) was used in a severely osteopenic rat model obtained by combining orchidectomy (ORX) and disuse (paralysis induced by botulinum toxin - BTX). Fifty-six aged male rats were randomized into three groups: 18 were SHAM operated; 38 were ORX and BTX injected in the right hindlimb; they constituted the OP (osteoporotic) group. One month after ORX-BTX surgery, 20 of these OP rats received a IBS1 injection in the right femur (OP-IBS1 rats). Animals were studied at the time of IBS1 injection 1 month post ORX-BTX (M1), 1 month (M2) and 2 months (M3) after IBS1 injection. Bone mass (BV/TV) and microarchitectural parameters were measured by microCT. BV/TV was decreased after ORX-BTX; ORX and BTX had cumulative effects on bone loss (differences maximized on the right femur). BV/TV (combining the volume of both bone and material in OP-IBS1 rats) was elevated at M1 but decreased at M2. Marked bone formation was found onto the biomaterial granules but bone had a woven texture. A marked increase in the number of nonosteoclastic TRAcP+ cells was found in the implanted area. IBS1 induced new bone formation shortly after implantation but both IBS1 and woven bone were resorbed without inducing lamellar bone. Biomaterial trials must be conducted with long-term implantation periods, in aged osteoporotic animals.

Topics: Aging; Animals; Bone Substitutes; Disease Models, Animal; Durapatite; Hypromellose Derivatives; Injections, Intralesional; Male; Methylcellulose; Osteoporosis; Rats; Rats, Wistar; Severity of Illness Index

The acute and chronic effects of ramelteon, an MT1/MT2 receptor agonist, were evaluated in rhesus monkeys (Macaca mulatta) to assess discriminative stimulus effects in comparison with traditional benzodiazepine receptor agonists and to assess physical dependence potential. Discriminative effects of ramelteon were compared with midazolam in untreated monkeys and in diazepam-dependent monkeys that discriminated flumazenil. Dependence potential of ramelteon after daily 1-year administration (and intermittent discontinuation) was evaluated with standard operant procedures. Ramelteon did not produce benzodiazepine-like discriminative stimulus effects at doses up to 10 mg/kg. Long-term treatment or its discontinuation had no significant effect on spontaneous behavior, operant behavior, body weight, motor activity, or posture. These findings suggest that ramelteon is not likely to have benzodiazepine-like abuse or dependence liability.

Topics: Analysis of Variance; Animals; Behavior, Animal; Benzodiazepines; Conditioning, Classical; Conditioning, Operant; Discrimination Learning; Discrimination, Psychological; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Flumazenil; GABA Modulators; Hypnotics and Sedatives; Indenes; Macaca mulatta; Male; Methylcellulose; Midazolam; Neuropsychological Tests; Receptors, Melatonin; Substance-Related Disorders; Time Factors

To use a novel porcine dry eye model (pDEM) to study the effect of various artificial tears on corneal abrasion and epithelial cell death under severe "dry eye" conditions.. A 60-second lacrimation-blink interval, which simulates a severe dry eye condition, was set up with our novel pDEM. The corneal protective effect of lubricating the eye for 4 hours with Dulbecco phosphate-buffered saline (DPBS, as control; n = 20) and with 3 types of commercially available artificial tears (n = 17 for each) that contained different lubricating agents was studied. Effect was determined in terms of the change in fluorescein staining grade (on a 0-4 point scale with 0.5 increments) of the cornea and the number of dead cells (by trypan blue staining) on the corneal surface.. Median increase in fluorescein grading (median) in corneas treated for 4 hours with artificial tears containing sodium hyaluronate or hydroxypropyl methylcellulose was significantly (P < 0.002) smaller than with artificial tears containing balanced saline with an unknown demulcent or the DPBS control. The numbers of dead epithelial cells in the central corneas lubricated with artificial tears containing sodium hyaluronate or hydroxypropyl methylcellulose (229 +/- 71 and 221 +/- 65 [SD], respectively) were also significantly (P < 0.005) smaller than those in the corneas of eyes lubricated with artificial tears containing balanced saline with an unknown demulcent or DPBS alone (328 +/- 106 and 341 +/- 113, respectively).. Results show that artificial tears containing sodium hyaluronate or hydroxypropyl methylcellulose as lubricating agents give enhanced corneal protection against desiccation and show the use of this novel pDEM model in evaluating corneal protection from desiccation.

Topics: Animals; Cell Survival; Cornea; Disease Models, Animal; Dry Eye Syndromes; Epithelial Cells; Fluoresceins; Hyaluronic Acid; Hypromellose Derivatives; Methylcellulose; Ophthalmic Solutions; Swine; Trypan Blue

Topics: Amoxicillin; Animals; Anti-Bacterial Agents; Anti-Ulcer Agents; Carcinogenicity Tests; Cell Proliferation; Disease Models, Animal; Drug Therapy, Combination; Epithelial Cells; Gastric Mucosa; Gerbillinae; Helicobacter Infections; Helicobacter pylori; Hypromellose Derivatives; Male; Methylcellulose; Omeprazole; Ophthalmic Solutions; Stomach Neoplasms

Our objectives were to identify serum marker proteins in rats that might serve as sensitive indicators of hepatomegaly, hepatocellular necrosis, or hepatobiliary injury and to use them to analyze data from a collaborative proteomics project.. In each of 4 studies comprising the collaborative project, rats were given 1 of 4 compounds that target the liver through different mechanisms. Sera and liver samples were collected by terminal bleeds at 1 of 3 postdose time points. Sera were depleted of major secretory proteins and then separated into protein features by 2-dimensional gel electrophoresis (2DGE). Liver specimens were also processed and subjected to 2DGE. Protein spots that significantly increased or decreased in quantity after drug treatment were recovered, digested, analyzed by mass spectroscopy, and compared with available databases for identification. Criteria for further consideration were (a) temporal expression (i.e., increase or decrease at early, fulminant, or recovery periods), (b) known biological function, (c) probable hepatic origin, and (d) any previous association with toxicity in published studies. Markers that changed significantly at the early time point were important because of their potential sensitivity for signaling minimal damage.. Vitamin D-binding protein, paraoxonase, cellular retinol-binding protein, malate dehydrogenase, F-protein, and purine nucleoside phosphorylase were identified as empirically confirmed serum markers for hepatic effects in drug-treated rats.. Proteomics can be applied for the identification and confirmation of peripheral biomarkers for altered liver function after toxicant exposure.

Topics: 1-Naphthylisothiocyanate; Acetaminophen; Animals; Biomarkers; Chemical and Drug Induced Liver Injury; Disease Models, Animal; Dose-Response Relationship, Drug; Hypertrophy; Liver Diseases; Male; Methylcellulose; Organ Size; Phenobarbital; Proteomics; Pyrimidines; Rats; Rats, Sprague-Dawley; Sensitivity and Specificity

The purposes of this study were to establish a quantitative method for evaluating rabbit tear film status and investigate the efficacy of artificial tear preparations through ocular surface bathing or eye drop application.. The rabbit tear film was evaluated using a noninvasive specular reflection video recording system. The appearance of a tear break area (TBA) on the tear film images (7.4 mm2/mm) after 30 seconds of eye opening was quantified by image analysis. To induce disruption of the rabbit tear film, the ocular surface was challenged for 60 minutes with 1 ppm hypochloric acid (HOCl). Immediately after irrigation, artificial tear preparations composed of viscosity agents sodium hyaluronate (SH), hydroxypropylmethycellulose (HPMC), hydroxyethylcellulose (HEC), or chondroitin sulfate (CS) were applied to the rabbit eye through ocular surface bathing or eye drop application, and the recovery of the disrupted tear film was compared for each preparation.. A dramatic increase in TBA was observed immediately after the ocular surface was challenged with HOCl, and it returned to the initial level after 6 hours. Immediately after ocular surface bathing and eye drop application, a dramatic recovery of TBA was observed in all the test solution-treated eyes. One hour after treatments, prolonged amelioration of the tear film instability was observed after ocular surface bathing, but not by eye drop application, with the artificial tear preparations composed of HPMC or SH.. Ocular surface bathing with artificial tear preparations composed of a suitable viscosity agents could be useful in managing tear film instability.

Topics: Animals; Cellulose; Chondroitin Sulfates; Disease Models, Animal; Dry Eye Syndromes; Hyaluronic Acid; Hypochlorous Acid; Hypromellose Derivatives; Methylcellulose; Ophthalmic Solutions; Rabbits; Tears; Viscosity

To characterize a new animal model of moderate chronic hyperpressure obtained by obstruction of the iridocorneal angle (ICA) in the minipig.. Intraocular hyperpressure was induced in one eye (left) using an injection of methylcellulose (4%) in the anterior chamber of six healthy adult minipigs. Intraocular pressure (IOP) was measured before injection and at D+60 and D+180. The clinical condition thus created was regularly assessed with the following procedures: fundus photography, electroretinography (ERG) to evaluate retinal function, scanning laser ophthalmoscopy (SLO) angiography to measure the arteriovenous filling times (AVFT). Optical microscopy was also performed to evaluate iridocorneal angle and inner retinal layers.. In all instances the injection produced a significant increase in the IOP accompanied by a mydriasis, as well as a significant increase in the AVFT and reduction (abolition in some cases) in the i-wave of the ERG. Fundus examination also revealed a blurred aspect and reduction in the calibre of the retinal blood vessels. Similarly, all experimental eyes showed, at optical microscopy, obstruction of the ICA as well a significant loss of of retinal ganglion cells.. Our results suggest that the above pathophysiological processes, triggered by the induced hyperpressure, share many similarities with human chronic open-angle glaucoma. Consequently, our model, which is very easy to create, could be used to test new therapeutic agents such as neuroprotective drugs.

Topics: Animals; Disease Models, Animal; Electroretinography; Fluorescein Angiography; Glaucoma, Open-Angle; Methylcellulose; Ocular Hypertension; Swine; Swine, Miniature

Topics: Animals; Cataract; Cytoprotection; Disease Models, Animal; Drug Combinations; Endothelium, Corneal; Formaldehyde; Lens, Crystalline; Methanol; Methylcellulose; Ophthalmology; Phacoemulsification; Swine

To establish models of experimental glaucoma in rabbits to investigate the treatment of glaucoma.. Twenty-one normal albino rabbits weighing 2.5 - 3.0 kg were studied. The rabbits were divided randomly into 4 groups: I, II, III and IV. Anterior chamber injection of 0.1 ml of 0.3% carbomer (I), 0.2 ml of methylcellulose (II), 0.2 ml of compound methylcellulose (III) and subconjunctival injection of 5 mg of dexamethasone (IV) were performed respectively on them to induce glaucoma. The intraocular pressure (IOP) was monitored with a Tono-pen XL tonometer several times prior to injection and 2 times per week after injection. The basic IOP in every group served as control.. Experimental glaucoma occurred in eleven of twelve eyes in group I and IOP lasted from 20 to 50 days. The mean IOP levels were 29 - 35 mmHg (1 mm Hg = 0.133 kPa) and the peak IOP levels were 37 - 45 mm Hg. The IOP in 2 out of 10 eyes in group II increased to 22 - 50 mm Hg and lasted for 3 days. The IOP of 1 out of 10 eyes in group III increased to 25 - 40 mm Hg and lasted for 4 days. The IOP in eyes of group IV increased only 3 mmHg in the mean and lasted for one week. According to the standard, IOP above 22 mmHg for one week as the successful experimental glaucoma, group II and III were not the ideal ones and group IV was a failure.. Experimental glaucoma model induced by carbomer has the advantages of producing moderate and sustained IOP elevation. The model is easy to be carried out. It is simple, reliable, and useful for investigating optic nerve and retinal damage in glaucoma and testing the toxicity and efficacy of various therapies.

Topics: Acrylic Resins; Animals; Dexamethasone; Disease Models, Animal; Female; Glaucoma; Intraocular Pressure; Male; Methylcellulose; Rabbits

It has been observed that with Masugi nephritis in Wistar rats the initiation of endocapillary proliferative changes with macrophage accumulation is usually followed by glomerular sclerosis without extracapillary extension. In the present study, the provocation of an extracapillary lesion was attempted using accelerated Masugi nephritis in Wistar-Kyoto rats. In order to accelerate the accumulation of monocyte/macrophages, the administration of methylcellulose was added in an additional group. The development and fate of extracapillary lesions were analyzed histopathologically and immunohistochemically. As a result, the formation of extracapillary proliferation of granulomatous lesions could be initiated in this model. Granulomatous lesions were composed of CD4+ T cells and CD8+ T cells and monocyte/macrophages including multinucleated giant cells. These inflammatory cells had seemingly escaped from the capillary lumen through the injured glomerular basement membrane and formed cellular and granulomatous crescents. In addition, tenascin was strongly expressed in cellular crescents and was a unique extracellular matrix at this cellular stage. The cellular crescents then progressed to sclerosis with the formation of increased collagenous extracellular matrix. These results suggest that a delayed-type hypersensitivity plays a role in granulomatous crescent formation, even though the initial glomerular injury was evoked by a humoral antibody.

Topics: Animals; Anti-Glomerular Basement Membrane Disease; Basement Membrane; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Disease Models, Animal; Freund's Adjuvant; Glomerulosclerosis, Focal Segmental; Granuloma; Immunohistochemistry; Kidney Glomerulus; Macrophages; Male; Methylcellulose; Phosphates; Proteinuria; Rabbits; Rats; Rats, Inbred WKY

With the intention of using the pig as a large animal model in haematopoietic research, a clonal assay in methylcellulose was developed and the optimal conditions for raising erythroid progenitors from adult pig bone marrow (BM) and peripheral blood (PB) have been established. Progenitor cells were stimulated to proliferate and differentiate in vitro by growth factors containing leucocyte condition medium (LCM), and with recombinant human erythropoietin (rhEpo). The number of PB BFU-E (burst forming units - erythroid) directly depended on the concentration of LCM, but BM BFU-E were not dependent on LCM. Both CFU-E (colony forming units - erythroid) and BFU-E were rhEpo dependent. Despite relatively high but expected individual variations, the mean number of colonies, as well as the functional characteristics of progenitor cells investigated, were similar to those of miniature pigs and some other mammals.

Topics: Animals; Bone Marrow Cells; Cell Culture Techniques; Colony-Forming Units Assay; Culture Media; Disease Models, Animal; Erythroid Precursor Cells; Humans; Methylcellulose; Swine

Various methodological approaches that can be used to detect ototoxic effects caused by the administration of various substances are presented, using the Sprague-Dawley rat as an animal model. Electrophysiological data are also presented to show how the model behaves with potentially ototoxic (hyaluronic acid) and initially inert (hydroxy-propyl-methyl-cellulose) substances.

Topics: Acoustic Stimulation; Adjuvants, Immunologic; Animals; Disease Models, Animal; Ear, Middle; Evoked Potentials, Auditory, Brain Stem; Hyaluronic Acid; Lactose; Methylcellulose; Microscopy, Electron; Mucous Membrane; Oxazines; Rats; Rats, Sprague-Dawley

To characterize the inflammation observed in amiodarone-induced pneumonitis.. The density of inflammatory cells in BAL fluid (BALF) and lung interstitium was quantified in a rat model of amiodarone pneumonitis. Immunoperoxidase staining for surfactant apoprotein was evaluated in lung tissue.. Male Fischer 344 rats weighing 170 to 180 g received amiodarone, 150 mg/kg/d, suspended in 0.5% methylcellulose by gavage 5 d/wk. Control animals were given only methylcellulose. Rats were killed after 3, 5, 7, 9, and 12 weeks. Histologic sections were prepared for hematoxylin-eosin staining and the immunoperoxidase method.. Significant positive correlations between the density of neutrophils in BALF and the interstitium were seen at 5 weeks (r=0.90, p<0.05) and 7 weeks (r=0.90, p<0.05). Significant positive correlations were observed between the density of lymphocytes in BALF and the interstitium at 9 weeks (r=0.90, p<0.05) and 12 weeks (r=0.90, p<0.05). The density of type II pneumocytes was significantly increased in the amiodarone-fed rats. Extracellular surfactant apoprotein was found in the alveolar space and the cytoplasm of type II pneumocytes, Clara cells, and large, foamy macrophages throughout drug treatment. Extracellular surfactant apoprotein filled some alveoli at 9 weeks.. The density of lymphocytes and neutrophils increased significantly in the BALF and the lung interstitium throughout amiodarone administration. The relationship between the density of lymphocytes in BALF and in the interstitium differed from that of neutrophils. In addition, amiodarone caused hyperplasia of type II pneumocytes and deposition of conglomerated, extracellular surfactant apoprotein in the alveolar space.

Topics: Amiodarone; Animals; Anti-Arrhythmia Agents; Apoproteins; Bronchoalveolar Lavage Fluid; Coloring Agents; Cytoplasm; Disease Models, Animal; Eosine Yellowish-(YS); Extracellular Space; Fluorescent Dyes; Foam Cells; Hematoxylin; Hyperplasia; Immunoenzyme Techniques; Leukocyte Count; Leukocytes; Lung; Lymphocyte Count; Lymphocytes; Macrophages, Alveolar; Male; Methylcellulose; Neutrophils; Pharmaceutic Aids; Pneumonia; Pulmonary Alveoli; Pulmonary Surfactants; Rats; Rats, Inbred F344; Time Factors

To examine the effects of a pepsin inhibitor, pepstatin-A, a long acting H2-receptor blocker, loxtidine, exogenous pepsin and exogenous acid against indomethacin-induced antral ulceration in the rat.. Indomethacin (60 mg/kg s.c.) caused antral ulceration in fasted/re-fed rats over a period of 4 h. Ulceration was prevented in a dose-dependent manner by treatment with pepstatin-A (0.1-1 mg.kg hourly) or loxtidine (3 mg/kg) given orally. Acidified methylcellulose (1 mL hourly per os) enhanced damage and also prevented protection by loxtidine (3 mg/kg per os). The protection by pepstatin-A was not altered by treatment with acidified methylcellulose but was reversed by treatment with a 10-fold excess of pepsin.. These studies suggest that mucosal degradation by pepsin, rather than direct damage by luminal acid, was the major factor in the development of indomethacin-induced antral ulceration in the rat.

Topics: Animals; Disease Models, Animal; Drug Interactions; Female; Gastric Mucosa; Indomethacin; Methylcellulose; Pepsin A; Pepstatins; Peptic Ulcer; Pyloric Antrum; Rats; Time Factors

The human osteosarcoma cell line, MG63, responds both to GM-CSF and to G-CSF in vitro. To assess the significance of these observations to tumor growth in vivo, MG63 cells were engineered by retroviral infection to produce human GM-CSF or G-CSF. These retrovirally infected cells become autostimulatory as measured by increased [3H]-thymidine incorporation (3- to 7-fold) and anchorage-independent colony formation (7- to 10-fold) as compared with uninfected MG63 cells or cells infected with control (neor) retrovirus. The increased proliferation induced by exogenous GM-CSF or G-CSF on uninfected MG63 cells in both assays could be completely inhibited by anti-GM-CSF or anti-G-CSF antibodies, while the same antibodies only partially abrogated proliferation by the growth-factor-producing cells. None of 34 nude or SCID mice developed tumors when injected s.c. with uninfected or neor-virus-infected cells. In contrast, all 30 mice injected with GM-CSF- or G-CSF-producing MG63 cells developed tumors which were G418-resistant and factor-producing. Tumor cell DNA showed a polyclonal retroviral integration pattern indistinguishable from that in the DNA of cells injected into mice. Tumors that formed following injection of a mixture of G418-resistant, GM-CSF-producing cells and cells infected with virus containing only the hygror gene contained hygromycin-resistant cells in the same proportion as was present in the original cell mixture. These data indicate that GM-CSF and G-CSF can support the growth of an osteosarcoma cell line both in vitro and in vivo whether the factor is supplied by autocrine production or from exogenous sources.

Topics: 3T3 Cells; Animals; Blotting, Southern; Bone Neoplasms; Carcinogenicity Tests; Cell Division; Disease Models, Animal; Female; Granulocyte Colony-Stimulating Factor; Granulocyte-Macrophage Colony-Stimulating Factor; Humans; Male; Methylcellulose; Mice; Mice, Inbred BALB C; Mice, Nude; Mice, SCID; Osteosarcoma; Retroviridae; Stimulation, Chemical; Tumor Cells, Cultured

Hydrogen peroxide (H2O2) has potent oxidant properties due to the action of free radicals (OH.) induced from its degradation. The free radicals specie derived from H2O2 are extremely toxic to the corneal endothelium and quickly induce corneal edema. In the present work, in order to ascertain the endothelial cell protection from viscoelastic substances, we have studied experimental corneal endothelial cell damage caused in the rabbit eye after intracameral injection of different H2O2 concentrations, with and without previous filling and washing out of two widely used viscoelastic substances from the anterior chamber such as 1% sodium hyaluronate (Healon) and hydroxypropylmethylcellulose (HPMC). We observed a dose-dependent endothelial damage in the controls. The experimental groups protected with Healon or HPMC showed statistically fewer corneal endothelial cell lesions than the control group (p < 0.001) for all of the concentrations used. Healon showed superior protective properties than HPMC at higher H2O2 concentrations (100 mM). However, HPMC was superior with 1 and 10 mM peroxide. From this experimental evidence, we conclude that Healon and HPMC are effective as protectors against the corneal endothelial lesions caused by free radicals. This finding may explain some of the beneficial effects of these viscoelastic substances.

Topics: Animals; Anterior Chamber; Disease Models, Animal; Endothelium, Corneal; Free Radicals; Hyaluronic Acid; Hydrogen Peroxide; Hypromellose Derivatives; Methylcellulose; Rabbits

There are many unanswered questions about chronic glaucoma which cannot be investigated in the available animal models. The present experiments were designed to develop a rabbit model of chronic intraocular hypertension with characteristics similar to human chronic glaucoma by ligating vortex veins or by making single or multiple intraocular injections of 0.5% or 1% alpha-chymotrypsin, 20% chondroitin sulphate, 2% hydroxypropyl methylcellulose, 2% sodium carboxymethylcellulose or 1% or 2% methylcellulose. Evaluation was based on the clinical findings, intraocular pressure and the retrograde axoplasmic transport function of the optic nerve using a horseradish peroxidase histochemical technique. Most methods either failed to produce moderate chronic intraocular hypertension or were associated with other complications. However, a reliable and relatively long period (eight weeks) of intraocular hypertension was developed by a series of four intra-anterior chamber injections of 1% or 2% methylcellulose. This model has been proved suitable for the study of structural and functional damage to the retina and optic nerve caused by chronic glaucoma.

Topics: Animals; Anterior Chamber; Cell Count; Chronic Disease; Disease Models, Animal; Female; Intraocular Pressure; Male; Methylcellulose; Ocular Hypertension; Rabbits

A reproducible model of an irregular corneal surface was developed to test the ability of the excimer laser to treat such surfaces. Using a 193-nm argon fluoride excimer laser set at a fluence of 160 mJ/cm2, repetition rate of 10 Hz, and 185 pulses, fresh de-epithelialized pig eyes underwent phototherapeutic ablations through a piece of stainless steel wire screen that masked the cornea. This yielded an uneven corneal surface in a grid-like pattern, with the peaks 50 microns higher than the troughs. The eyes then underwent further treatment in an attempt to smooth the center of the irregularity. Hydroxypropyl-methylcellulose 0.3% protected the valleys in 12 eyes; 2 eyes were ablated without a protecting fluid. The same laser, at the above noted settings, was used, except that both 2 Hz and 10 Hz frequencies were used. Immediately after treatment, the eyes were processed for scanning electron microscopy. The eyes treated at 2 Hz showed less surface irregularity than did those treated at 10 Hz. The eyes treated without a protecting fluid, regardless of repetition rate, had the greatest irregularities. This model is simple and reproducible, and the authors' results suggest that modifying the repetition rates of the excimer laser can influence its effectiveness in smoothing irregular corneas.

Topics: Animals; Cornea; Corneal Diseases; Disease Models, Animal; Hypromellose Derivatives; Laser Therapy; Methylcellulose; Microscopy, Electron, Scanning; Reproducibility of Results; Swine

Rough corneal surfaces may be smoothed by performing a superficial keratectomy with the 193 nm excimer laser. In order to smooth an irregular surface, a substance must be used during ablation to protect low corneal areas so that high spots are ablated preferentially. A simple, accurate, and reproducible method for modelling various corneal surface irregularities was developed. The technique uses the excimer laser to imprint the patterns of various metallic grids onto the stromal surface. The model was used to facilitate a comparison of three potential smoothing agents: 0.5% tetracaine, 2% hydroxypropylmethylcellulose, and a fluorescein-containing hyaluronate preparation. Preliminary results indicate that tetracaine may be the most efficacious smoothing agent.

Topics: Animals; Cornea; Corneal Diseases; Disease Models, Animal; Hyaluronic Acid; Hypromellose Derivatives; Laser Therapy; Methylcellulose; Microscopy, Electron, Scanning; Rabbits; Reproducibility of Results; Tetracaine

Topics: Animals; Disease Models, Animal; Female; Hypersplenism; Injections, Intraperitoneal; Methylcellulose; Rats; Rats, Inbred Strains

Topics: Animals; Antifoaming Agents; Disease Models, Animal; Hypertension, Portal; Liver Circulation; Male; Methylcellulose; Portal Vein; Rabbits; Silicones; Venous Pressure

After intraperitoneal injections of 2.5% aqueous methylcellulose twice a week for 15 weeks gerbils showed a mild haemolytic anaemia, heterophilia, lymphopenia and monocytosis. Many monocytes and a few lymphocytes had a foamy vacuolated cytoplasm. There was a sequestration of methylcellulose in the phagocytic cells of the spleen, liver, bone marrow and in other scattered foci, and consistent storage in the glomerular endothelium. Myeloid metaplasia was noted in the spleen, and splenic weights were markedly increased (P Less than 0.05); hepatomegaly was also present. The survival at the end of 15 weeks was 60%. From this experiment, the gerbil is considered to be a potential model for a stimulated monocyte-macrophage system.

Topics: Adrenal Glands; Animals; Animals, Laboratory; Blood; Bone Marrow; Disease Models, Animal; Gerbillinae; Kidney; Liver; Male; Methylcellulose; Spleen

Topics: Animals; Disease Models, Animal; Female; Hypersplenism; Leukocyte Count; Leukocytes; Macromolecular Substances; Methylcellulose; Mice; Osmolar Concentration; Phagocytosis

Topics: Aged; Anemia; Animals; Body Weight; Chromium Radioisotopes; Disease Models, Animal; Felty Syndrome; Female; Half-Life; Hemoglobins; Humans; Hypersplenism; Injections, Intraperitoneal; Iodine Radioisotopes; Methylcellulose; Organ Size; Plasma Volume; Prednisone; Rats; Spleen

Topics: Animals; Bronchography; Contrast Media; Disease Models, Animal; Dogs; Lung; Lung Diseases; Metabolic Clearance Rate; Methylcellulose; Phagocytosis; Respiration; Tantalum

Topics: Animals; Choroid; Disease Models, Animal; Eye; Glaucoma; Inbreeding; Intraocular Pressure; Methylcellulose; Optic Nerve; Rabbits; Retinal Vessels

Topics: Animals; Aqueous Humor; Disease Models, Animal; Epinephrine; Eye; Formaldehyde; Injections; Intraocular Pressure; Methylcellulose; Mydriatics; Norepinephrine; Phenethylamines; Phenols; Pupil; Rabbits; Structure-Activity Relationship; Vasoconstrictor Agents; Vasodilator Agents; Vitreous Body

Topics: Animals; Disease Models, Animal; Hematocrit; Hypersplenism; Malaria; Methylcellulose; Plasmodium; Rats; Splenomegaly

Topics: Agar; Animals; Animals, Laboratory; Arthritis, Infectious; Cricetinae; Culture Media; Culture Techniques; Disease Models, Animal; Freund's Adjuvant; Guinea Pigs; Injections; Injections, Intraperitoneal; Lymphoma, Non-Hodgkin; Methylcellulose; Mice; Mucins; Mycoplasma; Mycoplasma Infections; Rabbits; Rats; Sarcoma, Experimental; Sepsis; Silicon Dioxide; Talc; Virulence