sodium-dodecyl-sulfate and Disease-Models--Animal

In the development of inflammatory bowel disease (IBD), the gut microbiota has been established as a key factor. Recently, metabolomics has become important for understanding the functional relevance of gut microbial changes in disease. Animal models for IBD enable the study of factors involved in disease development. However, results from animal studies may not represent the human situation. The aim of this study was to investigate whether results from metabolomics studies on animal models for IBD were similar to those from studies on IBD patients. Medline and Embase were searched for relevant studies up to May 2017. The Covidence systematic review software was used for study screening, and quality assessment was conducted for all included studies. Data showed a convergence of ~17% for metabolites differentiated between IBD and controls in human and animal studies with amino acids being the most differentiated metabolite subclass. The acute dextran sodium sulfate model appeared as a good model for analysis of systemic metabolites in IBD, but analytical platform, age, and biological sample type did not show clear correlations with any significant metabolites. In conclusion, this systematic review highlights the variation in metabolomics results, and emphasizes the importance of expanding the applied detection methods to ensure greater coverage and convergence between the various different patient phenotypes and animal models of inflammatory bowel disease.

Topics: Animals; Disease Models, Animal; Humans; Inflammatory Bowel Diseases; Metabolome; Metabolomics; Mice; Sodium Dodecyl Sulfate; Translational Research, Biomedical

The stratum corneum's (SC) functions include protection from external hazardous environments, prevention of water loss and regulation of body temperature. While intact skin absorption studies are abundant, studies on compromised skin permeability are less common, although products are often used to treat affected skin. We reviewed literature on percutaneous absorption through abnormal skin models. Tape stripping is used to disrupt water barrier function. Studies demonstrated that physicochemical properties influence the stripping effect: water-soluble drugs are more affected. Abrasion did not affect absorption as much. Freezing is commonly used to preserve skin. It does not seem to modify water absorption, but still increases the penetration of compounds. Comparatively, heating the skin consistently increased percutaneous absorption. Removing SC lipids may increase percutaneous absorption of drugs. Many organic solvents are employed to delipidize. Delipidization with chloroform-methanol increased hydrophilic compound permeability, but not lipophilic. Acetone pre-treatment enhanced hydrophilic compound penetration. More data is needed to determine influence on highly lipophilic compound penetration. Sodium lauryl sulfate (SLS) induces irritant dermatitis and is frequently used as a model. Studies revealed that SLS increases hydrophilic compound absorption, but not lipophilic. However, skin irritation with other chemicals increases lipophilic penetration as much as hydrophilic. Animal studies show that UV exposure increases percutaneous absorption whereas human studies do not. Human studies show increased penetration in psoriatic and atopic dermatitis skin. The data summarized here begin to characterize flux alteration associated with damaged skin. Understanding the degree of alteration requires interpretation of involved conditions and the enlarging of our database to a more complete physicochemical spectrum.

Topics: Animals; Dermatitis, Atopic; Dermatitis, Irritant; Disease Models, Animal; Fatty Acids, Essential; Humans; Permeability; Skin; Skin Absorption; Sodium Dodecyl Sulfate

Various methodological aspects of skin sensitisation testing have been explored, particularly in the context of animal welfare considerations and reliability and sensitivity of test methods. Recommendations are made for the conduct of current and proposed OECD skin sensitisation tests with respect to appropriate test configurations for the purposes of hazard identification and labelling, and the requirement for positive controls. Specifically, the following aspects of guinea pig sensitisation test methods have been addressed: (1) the number of test and control animals required; (2) the option of using joint positive controls between independent laboratories; (3) the choice of positive control chemicals; (4) the optimal conduct and interpretation of rechallenge; and (5) the requirement for pretreatment with sodium lauryl sulfate. In addition, the use of the murine local lymph node assay (LLNA) has been considered. A number of conclusions have been drawn and recommendations made as follows: In many instances, particularly with the conduct of the guinea pig maximisation test, it is acceptable to halve the number of test and control animals used. An optional scheme for the conduct of joint positive control studies within a co-ordinated group of laboratories is appropriate. Only one positive control chemical (alpha-hexyl cinnamic aldehyde) is necessary for the routine assessment of assay sensitivity. The proper conduct and interpretation of rechallenge can provide valuable information and confirmation of results in guinea pig sensitisation tests. Sodium lauryl sulfate should no longer be used as a pretreatment in the guinea pig maximisation test. The LLNA is a viable and complete alternative to traditional guinea pig test methods for the purposes of skin sensitisation hazard identification. These recommendations provide the opportunity for both animal welfare benefits and improved hazard identification.

Topics: Allergens; Animal Welfare; Animals; Dermatitis, Allergic Contact; Disease Models, Animal; Guinea Pigs; Local Lymph Node Assay; Mice; Skin Tests; Sodium Dodecyl Sulfate; Surface-Active Agents

The effect of six skin-care formulations (SCFs) on experimentally induced cumulative irritation was studied in hairless guinea-pigs (HLGPs) and in human volunteers (HVs). The formulations were a basic cream, a carbomer cream and four modifications of the carbomer cream, containing either 10% isopropyl palmitate (IPP cream), 10% glycerol (glycerol cream), 19.5% canola oil (canola oil cream) or 0.5% (-)-alpha-bisabolol (bisabolol cream).. In HLGP, irritant dermatitis was induced with 30 min daily exposure for 4 days to 0.5% sodium lauryl sulfate aq. (SLS). In HVs, irritant dermatitis was induced with 10 min daily exposure for 5+4 days (no irritation on weekends) to 3% SLS aq. on the right and 30% nonanoic acid (NON) in n-propanol on the left volar forearm. Clinical scoring was performed daily; evaporimetry (total epidermal water loss (TEWL)), hydration and colorimetry were measured at baseline (day 0) in the middle and at the end of treatment. Treatments were applied twice daily. The basic cream and the IPP cream were excluded from testing in HLGP because they were known from previous studies to be irritant in HLGP, while all formulations were known to be equally and well tolerated locally in humans.. All formulations worsened the skin irritation in HLGP: the glycerol cream the least, the canola oil cream the most, while the bisabolol cream and the carbomer cream were indistinguishable. In humans, the glycerol cream was better than 'No Treatment' after cumulative irritation with both SLS and NON. The basic cream was better tolerated in humans than was expected from previous testing in HLGPs.. In conclusion, the results from the studies in HLGPs and HVs are in agreement with regard to ranking of the SCFs. Further, the glycerol cream showed a positive treatment effect on both SLS- and NON-irritated skin in HVs.

Topics: Administration, Topical; Adult; Animals; Cosmetics; Dermatitis, Contact; Dermatitis, Irritant; Disease Models, Animal; Female; Guinea Pigs; Hair; Humans; Male; Skin Care; Sodium Dodecyl Sulfate; Species Specificity; Treatment Outcome

Our aim was to assess the microdialysis technique for determining in vivo drug levels of a lipophilic and a protein-bound model drug in the dermis. Forearm skin of healthy volunteers received topical 2% fusidic acid or 0.1% betamethasone-17-valerate formulations twice daily as occluded treatment on irritative dermatitis. Microdialysis sampling in the dermis after 48 h was without measurable drug. Hairless rats received maximized treatment with occluded applications of 10% fusidic acid or 4% betamethasone-17-valerate in ethanol for 72 h followed by microdialysis. Mean levels of betamethasone-17-valerate were 11-45 ng/ml; fusidic acid was not measurable. Systemic administration in clinical doses to rats was without measurable drug levels; increasing doses to 312 mg/kg of fusidic acid and 158 mg/kg of betamethasone-17-valerate yielded betamethasone-17-valerate levels of 25-44 ng/ml and fusidic acid levels of 10-90 ng/ml. This study demonstrates the challenges arising when using microdialysis for measuring in vivo-drug levels. For the drugs chosen it was necessary to administer very high systemic doses or apply a high topical drug concentration to obtain measurable drug levels in the dialysates. Drug levels were in the nanomolar range and demonstrated reproducible and dynamic monitoring of in vivo drug levels in the skin. Using microdialysis for sampling highly protein-bound or lipophilic drugs in the skin requires very sensitive analytical methods, and the sensitivity of the analysis is likely to be the limiting factor.

Topics: Administration, Oral; Administration, Topical; Adult; Animals; Betamethasone; Cell Membrane Permeability; Chromatography, High Pressure Liquid; Disease Models, Animal; Feasibility Studies; Female; Fusidic Acid; Humans; Male; Microdialysis; Patch Tests; Protein Synthesis Inhibitors; Rats; Rats, Sprague-Dawley; Sensitivity and Specificity; Skin; Skin Absorption; Sodium Dodecyl Sulfate; Surface-Active Agents

Premna microphylla turcz is traditionally used as a folk remedy. Its roots, stems and leaves can be invoked as medicines, which have the functions of detoxification, swelling and hemostasis. It belongs to the Premna in the Verbenaceae and is mainly distributed in the mountains of southeastern China. However, there are few reports of in-depth studies on the anti-inflammatory effects of polysaccharide, which was the main component in Premna microphylla turcz.. The flies were fed with standard corn flour-yeast medium to cause inflammation by sodium lauryl sulfate (SDS). The treatment group contained Premna microphylla turcz polysaccharide (pPMTLs) extract. The survival rate was obtained by feeding a vial containing five layers of filter paper, which was infiltrated with the 5% sucrose solution contaminated with SDS or SDS polysaccharide. The microvilli and nucleus of the midgut epithelial cells of different treatments were observed by transmission electron microscope, and the expression of inflammation-related genes was detected by real-time quantitative PCR (qRT-PCR). Finally, 16S rDNA analysis was conducted on the differences in the composition of the intestinal microbes of Drosophila.. In the current study, we showed that pPMTLs significantly prolonged the life span of SDS-inflamed flies from 5 days to 6 days. And pPMTLs reduced the rupture of microvilli in the midgut and restored the nuclear structure. In addition, pPMTLs significantly improved expression level of immune-related genes in Inflammation Drosophila especially the defensin (4.32 ± 0.75 vs 9.97 ± 0.52 SDS-polysaccharide group: SDS group, p < 0.001). The analysis of intestinal microbiota showed that pPMTLs decreased the relative abundance of Raoultella while Wolbachia increased (p < 0.05).. Collectively, our results revealed the potential application of pPMTLs in enhancing inflammation defense, which would be enormous significance for the inflammation-related disorders treatment.

Topics: Animals; Autophagy; Disease Models, Animal; Drosophila melanogaster; Drosophila Proteins; Epithelial Cells; Female; Gastrointestinal Microbiome; Inflammation; Intestines; Lamiaceae; Metabolic Networks and Pathways; Plant Extracts; Polysaccharides; Pore Forming Cytotoxic Proteins; Principal Component Analysis; Protective Agents; Sodium Dodecyl Sulfate; Survival Rate; TOR Serine-Threonine Kinases

When Zika virus emerged as a public health emergency there were no drugs or vaccines approved for its prevention or treatment. We used a high-throughput screen for Zika virus protease inhibitors to identify several inhibitors of Zika virus infection. We expressed the NS2B-NS3 Zika virus protease and conducted a biochemical screen for small-molecule inhibitors. A quantitative structure-activity relationship model was employed to virtually screen ∼138,000 compounds, which increased the identification of active compounds, while decreasing screening time and resources. Candidate inhibitors were validated in several viral infection assays. Small molecules with favorable clinical profiles, especially the five-lipoxygenase-activating protein inhibitor, MK-591, inhibited the Zika virus protease and infection in neural stem cells. Members of the tetracycline family of antibiotics were more potent inhibitors of Zika virus infection than the protease, suggesting they may have multiple mechanisms of action. The most potent tetracycline, methacycline, reduced the amount of Zika virus present in the brain and the severity of Zika virus-induced motor deficits in an immunocompetent mouse model. As Food and Drug Administration-approved drugs, the tetracyclines could be quickly translated to the clinic. The compounds identified through our screening paradigm have the potential to be used as prophylactics for patients traveling to endemic regions or for the treatment of the neurological complications of Zika virus infection.

Topics: Animals; Antiviral Agents; Artificial Intelligence; Chlorocebus aethiops; Disease Models, Animal; Drug Evaluation, Preclinical; High-Throughput Screening Assays; Immunocompetence; Inhibitory Concentration 50; Methacycline; Mice, Inbred C57BL; Protease Inhibitors; Quantitative Structure-Activity Relationship; Small Molecule Libraries; Vero Cells; Zika Virus; Zika Virus Infection

Stringent regulation of the transcription factor NF-κB signaling is essential for the activation of host immune responses and maintaining homeostasis, yet the molecular mechanisms involved in its tight regulation are not completely understood. In this study, we report that IKK-interacting protein (IKIP) negatively regulates NF-κB activation. IKIP interacted with IKKα/β to block its association with NEMO, thereby inhibiting the phosphorylation of IKKα/β and the activation of NF-κB. Upon LPS, TNF-α, and IL-1β stimulation, IKIP-deficient macrophages exhibited more and prolonged IKKα/β phosphorylation, IκB, and p65 phosphorylation and production of NF-κB-responsive genes. Moreover, IKIP-deficient mice were more susceptible to LPS-induced septic shock and dextran sodium sulfate-induced colitis. Our study identifies a previously unrecognized role for IKIP in the negative regulation of NF-κB activation by inhibition of IKKα/β phosphorylation through the disruption of IKK complex formation.

Topics: Animals; Colitis; Disease Models, Animal; Gene Expression Regulation; HEK293 Cells; Humans; I-kappa B Kinase; Inflammation; Interleukin-1beta; Lipopolysaccharides; Male; Mice; Mice, Inbred C57BL; Mice, Mutant Strains; NF-kappa B; Peptide Fragments; Phosphorylation; Protein Binding; Sodium Dodecyl Sulfate; Tumor Necrosis Factor-alpha

Previous studies have shown that curcumin (Cur) induced by ultrasound has protective effects on atherosclerosis even if low bioavailability of the Cur. The enhancement of bioavailability of the Cur further improved the curative effect of sonodynamic therapy (SDT) on atherosclerosis through nanotechnology. Nanosuspensions as a good drug delivery system had obvious advantages in increasing the solubility and improving the effectiveness of insoluble drugs. The aim of this study was to develop curcumin nanosuspensions (Cur-ns) which used polyvinylpyrrolidone (PVPK30) and sodium dodecyl sulfate (SDS) as stabilizers to improve poor water solubility and bioavailability of the Cur. And then the therapeutic effects of Cur-ns-SDT on atherosclerotic plaques and its possible mechanisms would be investigated and elucidated. Cur-ns with a small particle size has been successfully prepared and the data have confirmed that Cur-ns could be more easily engulfed into RAW264.7 cells than free Cur and accumulated more under the stimulation of the ultrasound. Reactive oxygen species (ROS) inside RAW264.7 cells after SDT led to the decrease of mitochondrial membrane potential (MMP) and the higher expression of cleaved caspase-9/3. The results of in vivo experiments showed that Cur-ns-SDT reduced the level of total cholesterol (TC) and low density lipoprotein (LDL) and promoted the transformation from M1 to M2 macrophages, relieved atherosclerosis syndrome. Therefore, Cur-ns-SDT was a potential treatment of anti-atherosclerosis by enhancing macrophages apoptosis through mitochondrial pathway and inhibiting the progression of plaques by interfering with macrophages polarization.

Topics: Administration, Oral; Animals; Apoptosis; Atherosclerosis; Biological Availability; Cholesterol; Combined Modality Therapy; Curcumin; Disease Models, Animal; Drug Delivery Systems; Humans; Lipoproteins, LDL; Male; Membrane Potential, Mitochondrial; Mice; Mice, Knockout, ApoE; Nanoparticles; Particle Size; Pharmaceutical Vehicles; Povidone; RAW 264.7 Cells; Reactive Oxygen Species; Sodium Dodecyl Sulfate; Theranostic Nanomedicine; Ultrasonic Therapy

Cleaning products such as soaps, shampoos, and detergents are comprised mainly of surfactants, agents known to cause dermatitis and cutaneous hypersensitivity characterized by itching, stinging, and burning of the skin and scalp. However, the mechanisms underlying surfactant-induced cutaneous hypersensitivity remain unclear. In the present study, we investigated the mechanisms of cutaneous hypersensitivity in mice treated with the detergent sodium dodecyl sulfate (SDS). Repeated SDS application to the skin induced inflammation, xeroderma, and elongation of peripheral nerves into the epidermis. The number of neurons immunopositive for c-Fos, a well known marker of neural activity, was substantially higher (+441%) in spinal dorsal horn (SDH) lamina I-II (but not lamina III-VI) of SDS-treated mice compared to vehicle-treated mice. In vivo extracellular recording revealed enhanced spontaneous (+64%) and non-noxious mechanical stimulation-evoked firing (+139%) of SDH lamina I-II neurons in SDS-treated mice, and stimulation-evoked neuronal firing was sustained (+5333%) even after stimulation. The number of GFAP-positive (activated) astrocytes, but not Iba1-positive microglia, was also elevated (+137%) in SDH lamina I-II of SDS-treated mice compared to vehicle-treated mice. Peripheral nerve elongation and hyperexcitability of afferent or SDH neurons, possible associated with the activation of spinal astrocytes, may underlie cutaneous hypersensitivity induced by surfactants.

Topics: Animals; Astrocytes; Dermatitis, Contact; Disease Models, Animal; Epidermis; Male; Mice, Inbred C57BL; Peripheral Nerves; Physical Stimulation; Posterior Horn Cells; Sodium Dodecyl Sulfate

Mesenchymal stem cells (MSCs) have shown great promise in inflammatory bowel disease (IBD) treatment, owing to their immunosuppressive capabilities, but their therapeutic effectiveness is sometimes thwarted by their low efficiency in entering the inflamed colon and variable immunomodulatory ability in vivo. Here, we demonstrated a new methodology to manipulate MSCs to express CX3C chemokine receptor 1 (CX3CR1) and interleukin-25 (IL-25) to promote their delivery to the inflamed colon and enhance their immunosuppressive capability. Compared to MSCs without treatment, MSCs infected with a lentivirus (LV) encoding CX3CR1 and IL-25 (CX3CR1&IL-25-LV-MSCs) exhibited enhanced targeting to the inflamed colon and could further move into extravascular space of the colon tissues via trans-endothelial migration in dextran sodium sulfate (DSS)-challenged mice after MSC intravenous injection. The administration of the CX3CR1&IL-25-LV-MSCs achieved a better therapeutic effect than that of the untreated MSCs, as indicated by pathological indices and inflammatory markers. Antibody-blocking studies indicated that the enhanced therapeutic effects of dual-functionalized MSCs were dependent on CX3CR1 and IL-25 function. Overall, this strategy, which is based on enhancing the homing and immunosuppressive abilities of MSCs, represents a promising therapeutic approach that may be valuable in IBD therapy.

Topics: Animals; Colitis; CX3C Chemokine Receptor 1; Disease Models, Animal; Female; Interleukins; Lentivirus; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Mice; Rats; Sodium Dodecyl Sulfate; Treatment Outcome

Tissue loss as a consequence of congenital anomalies, trauma, malignancy, or gangrene represents a major health care problem in the United States. Because younger individuals are disproportionately affected, the costs are magnified over time and the resultant individual and societal effects are tremendous. The currently available options to restore soft tissue defects are associated with donor site morbidities. Vascularized composite allotransplantation may provide form, function, and esthetics without a donor site; however, it comes with the significant risk associated with toxic immunosuppression (Biomaterials. 2015;61:246-256, Ann Plast Surg. 2015;75(1):112-116, Transplantation. 2009;88(2):203-210). Engineered tissues offer promise in finding viable alternatives to allograft and autologous tissues. In this study, we present our simple and quick method to decellularize a muscle without disrupting the vascular network integrity or the extracellular matrix. Optimizing the decellularization process is a crucial step toward creating an "off-the-shelf" flap that can be used for soft tissue reconstruction.. The superficial gracilis muscle of 20 rats were harvested on their circulation and decellularized using perfusion with Krebs-Henseleit buffer and sodium dodecyl sulfate for 6 hours. These flaps were evaluated by gross morphology, histology, DNA quantification, integrity of the vascular network, scanning electron microscopy, and transmission electron microscopy.. All samples were decellularized successfully as determined by DNA content and histological analysis for cellular content. The vascular network was preserved in all samples.. We present a quick, simple, and affordable method to decellularize a muscle flap through the vascular network. Our proposed method is efficient and can be completed in a significantly shorter time when compared with other methods. It is also safe and does not affect integrity of tissue, and this is essential for a reliable recellularization.

Topics: Acellular Dermis; Animals; Biocompatible Materials; Cell-Free System; Disease Models, Animal; Gracilis Muscle; Humans; Perfusion; Rats; Sensitivity and Specificity; Sodium Dodecyl Sulfate; Soft Tissue Injuries; Surgical Flaps; Tissue and Organ Harvesting; Tissue Engineering

Low-grade intestinal inflammation and alterations of gut barrier integrity are found in patients affected by extraintestinal autoimmune diseases such as type 1 diabetes (T1D), but a direct causal link between enteropathy and triggering of autoimmunity is yet to be established. Here, we found that onset of autoimmunity in preclinical models of T1D is associated with alterations of the mucus layer structure and loss of gut barrier integrity. Importantly, we showed that breakage of the gut barrier integrity in

Topics: Animals; Bacteria; Blood Glucose; Colitis; Diabetes Mellitus, Type 1; Disease Models, Animal; Female; Gastrointestinal Microbiome; Gene Expression; Humans; Intestinal Mucosa; Islets of Langerhans; Mice; Mice, Inbred NOD; Mice, Transgenic; Permeability; Receptors, Antigen, T-Cell; Sodium Dodecyl Sulfate; Survival Analysis; T-Lymphocytes; Transgenes

Foxp3

Topics: Animals; Cell Movement; Cells, Cultured; Colitis; Colon; Disease Models, Animal; Forkhead Transcription Factors; Homeodomain Proteins; Humans; Immunosuppression Therapy; Inflammation; Lymph Nodes; Mice; Mice, Inbred C57BL; Mice, Transgenic; Receptors, Lysosphingolipid; Sodium Dodecyl Sulfate; Sphingosine-1-Phosphate Receptors; T-Lymphocytes, Regulatory; Tumor Suppressor Proteins

Oral drug delivery with nanoparticles has demonstrated great potential for drugs with poor bioavailability. Efficient delivery is possible by overcoming both the mucus and epithelial barrier of the gastrointestinal tract (GIT). Cationic lipid-assisted nanoparticles (CLANs), which are composed of amphiphilic block copolymers and cationic lipids, have been well studied and have been proved beneficial for drug delivery. In this study, CLANs prepared by poly(ethylene glycol)-block-poly(lactic acid) (PEG-b-PLA) and 1,2-dioleoyl-3-trimethylammonium-propanechloride (DOTAP) or N,N-bis(2-hydroxyethyl)-N-methyl-N-(2-cholesteryloxycarbonyl aminoethyl)ammoniumbromide (BHEM-Chol) were used for oral delivery of tacrolimus (FK506) for ulcerative colitis treatment. The average size of these nanoparticles is around 110 nm and the zeta-potential is 35 mV. These nanoparticles maintained their size in buffer solutions of pH 1.2 and 6.8, and slowly release the encapsulated drug. CLANs can be accumulated in the colon and transported through the epithelium in the colitis model by dextran sulfate sodium salt (DSS), leading to attenuation of DSS-induced colitis.

Topics: Administration, Oral; Animals; Anti-Inflammatory Agents; Cholesterol Esters; Colitis, Ulcerative; Disease Models, Animal; Drug Carriers; Drug Compounding; Drug Liberation; Fatty Acids, Monounsaturated; Female; Hydrogen-Ion Concentration; Kinetics; Lactates; Mice; Mice, Inbred C57BL; Nanoparticles; Particle Size; Polyethylene Glycols; Quaternary Ammonium Compounds; Sodium Dodecyl Sulfate; Tacrolimus

Calcium-permeable transient receptor potential (TRP) channels exist in eukaryotic cells from yeasts to animals and plants. and they act as sensors for various stresses. Arabidopsis thaliana calcium permeable stress-gated cation channel 1 (AtCSC1) was the first plant calcium-permeable TRP to be described and can be activated by hyperosmotic shock. Candida albicans CaPHM7 is one of the sequence homologs of AtCSC1, but its function remains unknown.. We show here that CaPhm7 is localized to the plasma membrane in both the yeast and hyphal cells of C. albicans. C. albicans cells lacking CaPHM7 are sensitive to SDS and ketoconazole but tolerant to rapamycin and zinc. In addition, deletion of CaPHM7 leads to a filamentation defect, reduced colony growth and attenuated virulence in the mouse model of systemic infection.. CaPhm7 is involved in the regulation of ion homeostasis, drug tolerance, filamentation and virulence in this important human fungal pathogen. CaPhm7 could be a potential target of antifungal drugs.

Topics: Animals; Candida albicans; Candidiasis; Disease Models, Animal; Drug Resistance, Fungal; Fungal Proteins; Homeostasis; Hyphae; Ketoconazole; Mice; Sirolimus; Sodium Dodecyl Sulfate; Transient Receptor Potential Channels; Virulence; Zinc

Fungi represent a significant proportion of the gut microbiota. Aberrant immune responses to fungi are frequently observed in inflammatory bowel diseases (IBD) and colorectal cancer (CRC), and mutations in the fungal-sensing pathways are associated with the pathogenesis of IBD. Fungal recognition receptors trigger downstream signaling via the common adaptor protein CARD9 and the kinase SYK. Here we found that commensal gut fungi promoted inflammasome activation during AOM-DSS-induced colitis. Myeloid cell-specific deletion of Card9 or Syk reduced inflammasome activation and interleukin (IL)-18 maturation and increased susceptibility to colitis and CRC. IL-18 promoted epithelial barrier restitution and interferon-γ production by intestinal CD8

Topics: Animals; CARD Signaling Adaptor Proteins; Cells, Cultured; Colitis; Colonic Neoplasms; Disease Models, Animal; Fungi; Gastrointestinal Microbiome; Humans; Inflammasomes; Inflammatory Bowel Diseases; Interleukin-18; Intestinal Mucosa; Mice; Mice, Inbred C57BL; Mice, Knockout; Myeloid Cells; Signal Transduction; Sodium Dodecyl Sulfate; Syk Kinase

There is a groundswell of interest in using genetically engineered sensor bacteria to study gut microbiota pathways, and diagnose or treat associated diseases. Here, we computationally identify the first biological thiosulfate sensor and an improved tetrathionate sensor, both two-component systems from marine

Topics: Animals; Bacterial Proteins; Biosensing Techniques; Colitis; Colon; Disease Models, Animal; Feces; Gastrointestinal Microbiome; Mice; Shewanella; Sodium Dodecyl Sulfate; Systems Biology; Tetrathionic Acid; Thiosulfates

The intestinal immune system is continuously exposed to massive amounts of nanoparticles derived from food. Whether nanoparticles from plants we eat daily have a role in maintaining intestinal immune homeostasis is poorly defined. Here, we present evidence supporting our hypothesis that edible nanoparticles regulate intestinal immune homeostasis by targeting dendritic cells (DCs). Using three mouse colitis models, our data show that orally given nanoparticles isolated from broccoli extracts protect mice against colitis. Broccoli-derived nanoparticle (BDN)-mediated activation of adenosine monophosphate-activated protein kinase (AMPK) in DCs plays a role in not only prevention of DC activation but also induction of tolerant DCs. Adoptively transferring DCs pre-pulsed with total BDN lipids, but not sulforaphane (SFN)-depleted BDN lipids, prevented DSS-induced colitis in C57BL/6 (B6) mice, supporting the role of BDN SFN in the induction of DC tolerance. Adoptively transferring AMPK

Topics: Administration, Oral; Adoptive Transfer; AMP-Activated Protein Kinases; Animals; Anti-Inflammatory Agents; Brassica; Colitis, Ulcerative; Dendritic Cells; Disease Models, Animal; Enzyme Activation; Gene Expression; Humans; Immune Tolerance; Isothiocyanates; Lipids; Mice; Mice, Inbred C57BL; Nanoparticles; Plant Extracts; Sodium Dodecyl Sulfate; Sulfoxides

To assess the counter-irritant and anti-inflammatory activity of Rumexvesicarius in dermatological use.. The animal-based experimental study was conducted at the Royal Institute of Medical Sciences, Multan, Pakistan, in November 2014. Sodium lauryl sulfate, phenol, histamine and sandpaper irritation models were used. Irritation was induced by the clockwise frictional movement of fine sandpaper to the ear of rabbits and then applying sodium lauryl sulfate, histamine and phenol single topical application onto the ear of the rabbit. The counter-irritant effect was determined by calculating the mean decrease in redness and erythema with those of control and standard dexamethasone.. There were 20 rabbits in the study with a mean weight of 1.50±0.033 kg. R. vesicarius (100 and 150mg/mL) showed excellent counter-irritant effect when compared with control and standard groups. Both the doses depicted counter-irritant effect with the highest inhibition (94.42%) in sandpaper group, followed by sodium lauryl sulphate (90%), phenol (94.23%) and histamine (88.46%) irritation models respectively.. Methanol leaf extract of R. vesicarius countered the effect of irritation in experimental animals. It showed significant effect in terms of dose and counter-irritancy time.

Topics: Animals; Anti-Inflammatory Agents; Dermatitis, Irritant; Disease Models, Animal; Disinfectants; Dose-Response Relationship, Drug; Friction; Histamine; Histamine Agonists; Methanol; Phenol; Plant Extracts; Plant Leaves; Rabbits; Rumex; Skin; Sodium Dodecyl Sulfate; Surface-Active Agents

Small incision lenticule extraction (SMILE) becomes a procedure to correct myopia. The extracted lenticule can be used for other clinical scenarios. To prepare for allogeneic implantation, lenticule decellularization with preserved optical property, stromal architecture and chemistry would be necessary. We evaluated different methods to decellularize thin human corneal stromal lenticules created by femtosecond laser. Treatment with 0.1% sodium dodecylsulfate (SDS) followed by extensive washes was the most efficient protocol to remove cellular and nuclear materials. Empty cell space was found inside the stroma, which displayed aligned collagen fibril architecture similar to native stroma. The SDS-based method was superior to other treatments with hyperosmotic 1.5 M sodium chloride, 0.1% Triton X-100 and nucleases (from 2 to 10 U/ml DNase and RNase) in preserving extracellular matrix content (collagens, glycoproteins and glycosaminoglycans). The stromal transparency and light transmittance was indifferent to untreated lenticules. In vitro recellularization showed that the SDS-treated lenticules supported corneal stromal fibroblast growth. In vivo re-implantation into a rabbit stromal pocket further revealed the safety and biocompatibility of SDS-decellularized lenticules without short- and long-term rejection risk. Our results concluded that femtosecond laser-derived human stromal lenticules decellularized by 0.1% SDS could generate a transplantable bioscaffold with native-like stromal architecture and chemistry.

Topics: Animals; Cornea; Corneal Stroma; Corneal Surgery, Laser; Corneal Transplantation; Disease Models, Animal; Humans; Rabbits; Sodium Dodecyl Sulfate; Tissue and Organ Harvesting; Tissue Engineering; Transplantation, Homologous

Protein precipitation with organic solvent is an effective means of depleting contaminants such as sodium dodecyl sulfate (SDS), while maintaining high analyte recovery. Here, we report the use of a disposable two-stage spin cartridge to facilitate isolation of the precipitated protein, with subsequent enzyme digestion and peptide cleanup in the cartridge. An upper filtration cartridge retains over 95% of the protein (10 μg BSA), with 99.75% detergent depleted from a sample initially containing 2% SDS. Following precipitation, a plug attached to the base of the filtration cartridge retains the solution to enable tryptic digestion in the vial, while a solid phase extraction cartridge attached to the base of the filter facilitates peptide cleanup post-digestion. A GELFrEE fractionated Escherichia coli proteome extract processed with the spin cartridge yields similar protein identifications compared to controls (226 vs 216 for control), and with an increased number of unique peptides (1753 vs 1554 for control). The device is applied to proteome characterization of rat kidneys experiencing a surgically induced ureteral tract obstruction, revealing several statistically altered proteins, consistent with the morphology and expected pathophysiology of the disease.. Conventionally, protein precipitation involves extended centrifugation to pellet the sample, with careful pipetting to remove the supernatant without disturbing the pellet. The method is not only time consuming but is highly subject to the skill of the individual, particularly at lower protein concentrations where the pellet may not be visible. As such, protein precipitation is often overlooked in proteomics, favoring column-based approaches to concentrate or purify samples. Here, all aspects of sample manipulation are integrated into a simple disposable cartridge. The device enables SDS depletion, sample preconcentration, resolubilization, derivatization, digestion, and peptide cleanup in a highly repeatable and easily multiplexed format. The device is ideally suited for comparative proteome studies. Antenatal hydronephrosis is a congenital disorder affecting 1-5% of all pregnancies, and can require surgical intervention to avoid loss of renal function. Using our device, we investigated the impact of hydronephrosis on the kidneys in a surgically induced animal model of the disease. Proteome analysis points to decreased metabolic activity in the obstructed kidney, with upregulation of proteins involved in cytoskeletal organization. This article is part of a Special Issue entitled: Protein dynamics in health and disease. Guest Editors: Pierre Thibault and Anne-Claude Gingras.

Topics: Animals; Disease Models, Animal; Escherichia coli; Escherichia coli Proteins; Hydronephrosis; Peptides; Proteome; Proteomics; Rats; Rats, Sprague-Dawley; Sodium Dodecyl Sulfate

Recently, decellularized tissues for organ transplantation and regeneration have been actively studied in the field of tissue engineering. In the decellularization process, surfactants such as sodium dodecyl sulfate (SDS) have been most commonly used to remove cellular components from the tissue. However, the residual surfactant may be cytotoxic in vivo and has been reported to hinder remodeling after implantation. In addition, treatment with surfactants may destroy the important extracellular matrix (ECM) structure that allows the decellularized tissue to function as a scaffold for cells. In this study, decellularized tissues with high biocompatibility were created using the recipient's serum. By immersing a heterogeneous tissue in serum conditioned to activate the complement system and DNase I, its cellular components could be removed. Compared to an SDS-treated graft, the serum-treated graft preserved the native structure of its ECM. When subcutaneously implanted into an isogenic inbred rat, the graft treated with the recipient's serum resulted in less immunorejection than did the SDS-treated graft.

Topics: Animals; Autografts; Carotid Arteries; Disease Models, Animal; Extracellular Matrix; Graft Rejection; Humans; Rats; Sodium Dodecyl Sulfate; Swine; Tissue Engineering; Tissue Scaffolds; Transplantation Conditioning; Transplantation, Autologous

The biological mechanisms predisposing intracranial saccular aneurysms to growth and rupture are not yet fully understood. Mural cell loss is a histological hallmark of ruptured cerebral aneurysms. It remains unclear whether mural cell loss predisposes to aneurysm growth and eventual rupture.. Sodium dodecyl sulfate decellularized and nondecellularized saccular aneurysm from syngeneic thoracic aortas were transplanted to the abdominal aorta of Wistar rats. Aneurysm patency and growth was followed up for 1 month with contrast-enhanced serial magnetic resonance angiographies. Endoscopy and histology of the aneurysms were used to assess the role of periadventitial environment, aneurysm wall, and thrombus remodeling.. Nondecellularized aneurysms (n=12) showed a linear course of thrombosis and remained stable. Decellularized aneurysms (n=12) exhibited a heterogeneous pattern of thrombosis, thrombus recanalization, and growth. Three of the growing aneurysms (n=5) ruptured during the observation period. Growing and ruptured aneurysms demonstrated marked adventitial fibrosis and inflammation, complete wall disruption, and increased neutrophil accumulation in unorganized intraluminal thrombus.. In the presented experimental setting, complete loss of mural cells acts as a driving force for aneurysm growth and rupture. The findings suggest that aneurysms missing mural cells are incapable to organize a luminal thrombus, leading to recanalization, increased inflammatory reaction, severe wall degeneration, and eventual rupture.

Topics: Animals; Aorta, Thoracic; Aortic Aneurysm; Aortic Rupture; Cerebral Angiography; Data Interpretation, Statistical; Disease Models, Animal; Disease Progression; Endoscopy; Endothelial Cells; Endothelium, Vascular; Image Processing, Computer-Assisted; Immunohistochemistry; Magnetic Resonance Imaging; Male; Paraffin Embedding; Rats; Rats, Wistar; Sodium Dodecyl Sulfate; Surface-Active Agents; Thrombosis

Shampoo and cleansers containing anionic surfactants including sodium dodecyl sulphate (SDS) often cause pruritus in humans. Daily application of 1-10% SDS for 4 days induced hind-paw scratching (an itch-related behaviour) in a concentration-dependent manner, and 10% SDS also caused dermatitis, skin dryness, barrier disruption, and an increase in skin surface pH in mice. SDS-induced scratching was inhibited by the opioid receptor antagonist naloxone and the H histamine receptor antagonist terfenadine. Mast-cell deficiency did not inhibit SDS-induced scratching, although it almost completely depleted histamine in the dermis. Treatment with SDS increased the histamine content of the epidermis, but not that of the dermis. SDS treatment increased the gene expression and post-translation processing of L-histidine decarboxylase in the epidermis. The present results suggest that repeated application of SDS induces itch through increased production of epidermal histamine, which results from an increase in the gene expression and post-translation processing of L-histidine decarboxylase.

Topics: Animals; Behavior, Animal; Disease Models, Animal; Enzyme Induction; Epidermis; Histamine; Histamine H1 Antagonists; Histidine Decarboxylase; Male; Mast Cells; Mice, Inbred ICR; Narcotic Antagonists; Protein Processing, Post-Translational; Pruritus; Sarcosine; Signal Transduction; Sodium Dodecyl Sulfate; Surface-Active Agents; Time Factors; Up-Regulation

Candida albicans is a common opportunistic pathogen that causes a wide variety of diseases in a human immunocompromised host leading to death. In a pathogen, cell wall proteins are important for stability as well as for acting as antigenic determinants and virulence factors. Pir32 is a cell wall protein and member of the Pir protein family previously shown to be upregulated in response to macrophage contact and whose other member, Pir1, was found to be necessary for cell wall rigidity. The purpose of this study is to characterize Pir32 by generating a homozygous null strain and comparing the phenotype of the null with that of the wild-type parental strain as far as filamentation, virulence in a mouse model of disseminated candidiasis, resistance to oxidative stress and cell wall disrupting agents, in addition to adhesion, biofilm capacities, and cell wall chitin content. Our mutant was shown to be hyperfilamentous, resistant to sodium dodecyl sulfate, hydrogen peroxide, sodium chloride, and more virulent in a mouse model when compared to the wild type. These results were unexpected, considering that most cell wall mutations weaken the wall and render it more susceptible to external stress factors and suggests the possibility of a cell surface compensatory mechanism. As such, we measured cell wall chitin deposition and found a twofold increase in the mutant, possibly explaining the above-observed phenotypes.

Topics: Animals; Candida albicans; Candidiasis; Cell Wall; Chitin; Disease Models, Animal; Fungal Proteins; Gene Deletion; Hydrogen Peroxide; Mice; Mice, Inbred BALB C; Microbial Viability; Microscopy; Osmotic Pressure; Oxidative Stress; Sodium Chloride; Sodium Dodecyl Sulfate; Stress, Physiological; Virulence

Topics: Animals; Cell Line; Dermatitis; Disease Models, Animal; Epidermis; Gene Expression Regulation; Humans; Kallikreins; Keratinocytes; Keratosis; Melanosis; Mice; Mice, Inbred C57BL; Mice, Knockout; Nerve Growth Factor; Real-Time Polymerase Chain Reaction; Receptors, Nerve Growth Factor; RNA Interference; RNA, Messenger; Sodium Dodecyl Sulfate; Transfection

Toxoplasmic encephalitis (TE) is the most common clinical manifestation of reactivated infection with Toxoplasma gondii in immunocompromised patients that is lethal if untreated. The combination of pyrimethamine plus sulfadiazine or clindamycin is the standard therapy for the treatment of TE, but these combinations are associated with hematologic toxicity and/or life-threatening allergic reactions. Therefore, alternative treatment options are needed. Atovaquone is safe and highly effective against T. gondii in vitro, but the oral micronized solution shows poor bioavailability. We synthesized atovaquone nanosuspensions (ANSs) coated with poloxamer 188 (P188) and sodium dodecyl sulfate (SDS) to improve oral bioavailability and passage through the blood-brain barrier (BBB). Coating of ANSs with SDS resulted in enhanced oral bioavailability and enhanced brain uptake of atovaquone compared to Wellvone(®) in murine models of acute and reactivated toxoplasmosis as measured by high performance liquid chromatography (HPLC). Parasite loads and inflammatory changes in brains of mice treated with SDS-coated ANS were significantly reduced compared to untreated controls and to Wellvone(®)-treated mice. In conclusion, nanosuspensions coated with SDS may ultimately lead to improvements in the treatment of TE and other cerebral diseases.

Topics: Administration, Oral; Animals; Antiprotozoal Agents; Atovaquone; Biological Availability; Brain; Chromatography, High Pressure Liquid; Disease Models, Animal; Excipients; Mice; Nanoparticles; Poloxamer; Sodium Dodecyl Sulfate; Suspensions; Tissue Distribution; Toxoplasma; Toxoplasmosis, Animal; Toxoplasmosis, Cerebral

Pathogenic mycobacteria possess two homologous chaperones encoded by cpn60.1 and cpn60.2. Cpn60.2 is essential for survival, providing the basic chaperone function, while Cpn60.1 is not. In the present study, we show that inactivation of the Mycobacterium bovis BCG cpn60.1 (Mb3451c) gene does not significantly affect bacterial growth in 7H9 broth, but that this knockout mutant (Δcpn60.1) forms smaller colonies on solid 7H11 medium than the parental and complemented strains. When growing on Sauton medium, the Δcpn60.1 mutant exhibits a thinner surface pellicle and is associated with higher culture filtrate protein content and, coincidentally, with less protein in its outermost cell envelope in comparison with the parental and complemented strains. Interestingly, in this culture condition, the Δcpn60.1 mutant is devoid of phthiocerol dimycocerosates, and its mycolates are two carbon atoms longer than those of the wild-type, a phenotype that is fully reversed by complementation. In addition, Δcpn60.1 bacteria are more sensitive to stress induced by H(2)O(2) but not by SDS, high temperature or acidic pH. Taken together, these data indicate that the cell wall of the Δcpn60.1 mutant is impaired. Analysis by 2D gel electrophoresis and MS reveals the upregulation of a few proteins such as FadA2 and isocitrate lyase in the cell extract of the mutant, whereas more profound differences are found in the composition of the mycobacterial culture filtrate, e.g. the well-known Hsp65 chaperonin Cpn60.2 is particularly abundant and increases about 200-fold in the filtrate of the Δcpn60.1 mutant. In mice, the Δcpn60.1 mutant is less persistent in lungs and, to a lesser extent, in spleen, but it induces a comparable mycobacteria-specific gamma interferon production and protection against Mycobacterium tuberculosis H37Rv challenge as do the parental and complemented BCG strains. Thus, by inactivating the cpn60.1 gene in M. bovis BCG we show that Cpn60.1 is necessary for the integrity of the bacterial cell wall, is involved in resistance to H(2)O(2)-induced stress but is not essential for its vaccine potential.

Topics: Animals; Anti-Bacterial Agents; Bacterial Load; Bacterial Proteins; Cell Wall; Culture Media; Disease Models, Animal; Electrophoresis, Gel, Two-Dimensional; Gene Knockout Techniques; Genetic Complementation Test; Hydrogen Peroxide; Lipids; Lung; Mass Spectrometry; Mice; Mice, Inbred BALB C; Molecular Chaperones; Mycobacterium bovis; Mycolic Acids; Oxidative Stress; Proteome; Rodent Diseases; Sodium Dodecyl Sulfate; Spleen; Tuberculosis

Hyperkeratosis and acanthosis occur in inflamed skin. Proliferation and differentiation of keratinocytes are important processes during epidermal repair after inflammation. Neuropsin and its human homologue kallikrein-related peptidase 8 (KLK8) have been reported to be involved in epidermal proliferation and differentiation, but the involved molecular mechanisms are obscure.. To explore the molecular mechanism of KLK8/neuropsin-induced hyperkeratosis and acanthosis in inflamed skin.. The molecular mechanism involved in KLK8/neuropsin-induced hyperkeratosis and acanthosis in inflamed skin was investigated both in vivo and in vitro using neuropsin knockout mice and KLK8 knockdown human keratinocytes. Neuropsin-related genes were identified by differential gene display. The localization and functional relationship of the molecules affected downstream of KLK8/neuropsin in normal and inflamed skin were analysed by in situ hybridization and immunohistochemistry..   Hyperkeratosis and acanthosis in sodium lauryl sulphate-stimulated skin were markedly inhibited in neuropsin knockout mice. Knockdown of KLK8/neuropsin increased transcription factor activator protein-2α (AP-2α) expression and decreased keratin 10 expression in human keratinocytes and mouse skin, respectively. AP-2α has been reported to inhibit epidermal proliferation and keratin 10 expression. Distributional analysis showed that KLK8/neuropsin was expressed in the stratum spinosum, AP-2α was expressed in the stratum basale and the lower part of the stratum spinosum, and keratin 10 was expressed throughout the stratum spinosum.. The above findings suggest the following mechanism of events underlying KLK8/neuropsin-induced hyperkeratosis: (i) skin inflammation increases KLK8/neuropsin expression in the stratum spinosum; (ii) the released KLK8/neuropsin inhibits AP-2α expression in the cells of the stratum basale and stratum spinosum; (iii) the decrease in AP-2α results in cell proliferation in the stratum basale and cell differentiation in the stratum spinosum, with an increase in keratin 10 expression.

Topics: Acanthosis Nigricans; Animals; Dermatitis; Disease Models, Animal; Humans; Hyperkeratosis, Epidermolytic; Immunohistochemistry; Kallikreins; Keratin-10; Keratinocytes; Mice; Mice, Knockout; Polymerase Chain Reaction; Skin; Sodium Dodecyl Sulfate; Transcription Factor AP-2; Up-Regulation

In polyglutamine (polyQ) degeneration, disease protein that carries an expanded polyQ tract is neurotoxic. Expanded polyQ protein exists in different conformations that display distinct solubility properties. In this study, an inducible transgenic Drosophila model is established to define the pathogenic form of polyQ protein at an early stage of degeneration in vivo. We show that microscopic polyQ aggregates are neither pathogenic nor protective. Further, no toxic effect of sodium dodecyl sulfate (SDS) -soluble polyQ protein is observed in our model. By means of filtration, 2 forms of SDS-insoluble protein species are identified according to their size. Coexpression of an ATPase-defective form of the molecular chaperone Hsc70 (Hsc70-K71S) selectively reduces the abundance of the large SDS-insoluble polyQ species, but such modulation has no modifying effects on degeneration. Notably, we detect a distinct Hsc70-K71S-resistant, small, SDS-insoluble polyQ oligomeric species that is closely correlated with degeneration. Our data highlight the toxic role of SDS-insoluble oligomers in polyQ degeneration in vivo.

Topics: Animals; Disease Models, Animal; Drosophila melanogaster; HSC70 Heat-Shock Proteins; Mice; Neurodegenerative Diseases; Peptides; Protein Conformation; Sodium Dodecyl Sulfate; Solubility

It has been suggested that the recent increase in inflammatory diseases is related to an increase in environmental chemicals and psychiatric stress. To investigate the effect of chronic topical exposure to chemicals and isolation stress, low-dose formalin (a mild contact sensitizer and an irritant), 2,4,6-trinitrochlorobenzene (TNCB; a potent contact sensitizer) and sodium lauryl sulphate (SLS; an irritant) were applied to mouse ears at 7-d intervals under no-stress or stress conditions. Skin reactions (ear swelling) elicited by formalin and TNCB increased time dependently. At the chronic stage, a significant skin reaction peaking at 1 h after application was elicited on the formalin-treated sites, while a shift from a delayed-type hypersensitivity to an immediate-type response was observed on the TNCB-treated sites. At the formalin-treated sites, genes related to neurogenic inflammation, i.e., bradykinin (BK) B2 receptor, IL-6, and membrane metallo endopeptidase (NEP) mRNA were upregulated. In the TNCB-treated sites, marked upregulation of IFN-gamma, IL-1beta, IL-4, and IL-6 mRNA was observed in addition to B2 receptor mRNA. Pretreatment with HOE140, the B2 receptor antagonist suppressed these skin reactions. Increased skin sensitivity to an unrelated chemical, ethanol, and thermal stimuli were elicited in formalin and TNCB-treated mice. Cortisol levels in formalin-treated mice and IgE levels in TNCB-treated mice were elevated respectively. Stress markedly amplified the skin reactions and gene expression related to neurogenic inflammation. SLS did not induce any changes. It was concluded that chronic topical exposure to low-dose noxious chemicals and stress could easily induce skin sensitivity relating to the BK-B2 pathway and nociceptive sensitization reflecting neural sensitization.

Topics: Administration, Topical; Animals; Chronic Disease; Dermatitis, Allergic Contact; Disease Models, Animal; Environmental Exposure; Gene Expression; Inflammation; Male; Mice; Picryl Chloride; Risk Factors; Skin Diseases; Sodium Dodecyl Sulfate; Stress, Psychological; Time Factors

Topics: Administration, Oral; Animals; Ascorbic Acid; Cysteine; Disease Models, Animal; Drug Therapy, Combination; Guinea Pigs; Male; Riboflavin; Skin; Skin Diseases; Sodium Dodecyl Sulfate; Vitamin B 6

Immuno-proteasome is thought to be responsible for the processing of intracellular antigens and is induced when cells are treated with the inflammatory cytokines promoting cellular immunity. We tested the possibility that immuno-proteasome can be up-regulated in renal cells exposed to a long-lasting ischemia and inflammation in an experimental model of two-kidney, one-clip renovascular hypertension in the rat. Western blotting showed that immuno-proteasome subunit, LMP7, was up-regulated in the clipped ischemic kidney that was atrophic, but not in the contralateral unclipped kidney that underwent compensatory hypertrophy. Immunohistochemical analysis revealed that LMP7 was highly expressed in cortical epithelial and endothelial cells of the ischemic kidney. Surprisingly, the second immuno-subunit, LMP2, was almost undetectable, indicating that renal ischemia may induce exclusively the LMP7 subunit. We also found that renal ischemia neither reduced the SDS-stimulated proteasomal activity nor affected a high level of the PA28 activator. Thus, the results provide evidence that LMP7 immuno-subunit is induced in renal cells exposed to a long-lasting renal ischemia and inflammation, and that there is a direct link between LMP induction and renal atrophy. This opens an opportunity to study a role for LMP-containing proteasomes in the kidneys and other organs undergoing reduction in mass in diseases accompanied by a long-lasting ischemia and inflammatory responses.

Topics: Animals; Disease Models, Animal; Hypertension, Renovascular; Ischemia; Kidney; Male; Multienzyme Complexes; Proteasome Endopeptidase Complex; Protein Subunits; Rats; Rats, Wistar; Sodium Dodecyl Sulfate; Up-Regulation

To determine how much barrier-reinforcing effects of ceramides contribute to prevent the surfactant-induced cutaneous deterioration.. We compared the effects of topical application of two types of pseudoceramides on cutaneous deterioration induced by sodium dodecyl sulfate (SDS) treatment for 10 days in association with alterations of barrier function.. Daily application of pseudoacylceramide immediately after each SDS treatment significantly prevented the marked elevation of transepidermal water loss, which was accompanied by a marked abrogation of the increased expression in intercellular adhesion molecule 1 by epidermal cells as well as by suppressed epidermal hyperplasia. In contrast, topical application of a nonacylated pseudoceramide with poor barrier-reinforcing potential showed less preventive effects on cutaneous deterioration.. These results strongly suggest that perturbation of the skin barrier is a causative factor in surfactant-induced cutaneous changes and that reinforcing the barrier function by ceramide application is effective in preventing the surfactant-induced skin deterioration.

Topics: Administration, Topical; Analysis of Variance; Animals; Ceramides; Dermatitis, Irritant; Disease Models, Animal; Epidermis; Female; Guinea Pigs; Intercellular Adhesion Molecule-1; Permeability; Probability; Risk Factors; Sensitivity and Specificity; Skin Absorption; Sodium Dodecyl Sulfate; Surface-Active Agents; Water Loss, Insensible

We report the conformational and toxic properties of two novel fibril-forming prion amyloid sequences, GAVVGGLG (PrP(119-126)) and VVGGLGG (PrP(121-127)). The conformational preferences of these fragments were studied in differing microenvironments of TFE/water mixtures and SDS solution. Interestingly, with an increase in TFE concentration, PrP(119-126) showed a helical conformational propensity, whereas PrP(121-127) adopted a more random coil structure. In 5% SDS, PrP(119-126) showed more alpha-helical content than in TFE solution, and PrP(121-127) exhibited a predominantly random coil conformation. However, both peptides took a random coil conformation in water, and over time the random coil transformed into a beta-sheet structure with a significant percentage of helical conformation and beta-turn structure in PrP(119-126) and PrP(121-127), respectively, as observed with CD spectroscopy. The aged fibrils of PrP(119-126) were insoluble in SDS, and PrP(121-127) was extractable with SDS solution. These fibrils were characterized by transmission electron microscopy. Both PrP(119-126) and PrP(121-127) formed stable monolayer's consisting of multimeric assemblages at the air-water interface. Monomeric PrP(119-126) was more toxic to astrocytes than the control Abeta peptide; however, the fibrillar form of PrP(119-126) was less toxic to astrocytes. PrP(121-127) elicited moderate toxicity in both soluble and fibrillar forms on astrocytes. Furthermore, quenching experiments using acroyl-labeled PrP(119-126) and PrP(121-127) with eosin-labeled synaptosomal membrane revealed that these prion fragments bind to anion-exchange protein. The binding of PrP(119-126) and PrP(121-127) with a membrane microdomain (lipid raft) was also analyzed using pyrenated derivatives. We conclude that the formation of PrP(119-126) and PrP(121-127) fibrils is a concentration-dependent process that involves coil to sheet conversion with aging. PrP(119-126), the sequence with intrinsic helical propensity, is more toxic in monomer form, and the fibril formation in this case seems to be protective to cells. For PrP(121-127), the SDS-soluble fibrils are more cytotoxic, indicating that a higher order assemblage structure is required for cytotoxic activity of this peptide.

Topics: Amyloid; Amyloid beta-Peptides; Animals; Astrocytes; Chromatography, Gel; Chromatography, Ion Exchange; Circular Dichroism; Disease Models, Animal; Lipids; Membrane Microdomains; Microscopy, Electron, Transmission; Peptide Fragments; Peptides; Prions; Protein Binding; Protein Conformation; Protein Structure, Secondary; Protein Structure, Tertiary; Pyrenes; Rats; Rats, Wistar; Sodium Dodecyl Sulfate; Spectrometry, Fluorescence; Spectroscopy, Fourier Transform Infrared; Synaptosomes; Temperature; Tetrazolium Salts; Thiazoles

Topics: Animals; Aorta; Apoptosis; Arteriosclerosis; Base Sequence; bcl-2-Associated X Protein; Cholesterol, Dietary; Diet, Atherogenic; Disease Models, Animal; DNA Primers; Electrophoresis, Polyacrylamide Gel; Gene Expression Regulation; Muscle, Smooth, Vascular; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-bcl-2; Rabbits; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sodium Dodecyl Sulfate

Microbicides are being developed for woman-controlled protection against sexually transmitted diseases (STDs).. The goal of the study was to test candidate microbicides in a mouse model for preventing vaginal transmission of and for acute toxicity to columnar epithelium.. Progestin-sensitized CF-1 mice were treated vaginally with 50 microl of microbicide, followed either by vaginal inoculation with 10 ID(50) of serovar D or by examination of the epithelial surface for acute toxicity with a viability stain (ethidium homodimer-1).. Nonoxynol-9 (N9), sodium dodecyl sulfate (SDS), chlorhexidine digluconate, and BufferGel all provided significant though incomplete protection against vaginal transmission. Other candidates, all of which were effective in vitro, provided no vaginal protection: kappa-carrageenan, dextran sulfate, polystyrene sulfonate, Concanavalin A, wheat germ agglutinin, and agglutinin. The surface-active agents (N9, SDS, and chlorhexidine) caused significant acute epithelial toxicity: 3 days after chlorhexidine exposure, mice also had vaginal friability and markedly increased susceptibility to. BufferGel was the only candidate tested that was both protective and relatively nontoxic.. Microbicides can provide vaginal protection against in highly susceptible progestin-sensitized mice. Since N9 does not inactivate, it likely protects by killing target cells in the vagina. Despite the ability to both potently inactivate and kill target cells, two surface-active agents, SDS and chlorhexidine, failed to provide complete protection, a circumstance which emphasizes the importance of distributing microbicides to all susceptible surfaces.

Topics: Acrylic Resins; Administration, Intravaginal; Animals; Anti-Infective Agents, Local; Chlamydia Infections; Chlamydia trachomatis; Chlorhexidine; Disease Models, Animal; Female; Mice; Nonoxynol; Sodium Dodecyl Sulfate; Spermatocidal Agents; Treatment Outcome

Salmonella enterica serovar Enteritidis is a major cause of food-borne diseases associated with consumption of shell eggs. Clinical isolates of S. enterica serovar Enteritidis exhibit a wide spectrum of virulence in mice. A highly virulent isolate (SE2472) was previously shown to be more resistant in vitro than other clinical isolates to acidified sodium nitrite (ASN), a generator of reactive nitrogen and oxygen intermediates (RNI/ROI). SE2472 is also more resistant to S-nitrosoglutathione (GSNO) and hydrogen peroxide (H(2)O(2)) than an ASN-susceptible isolate of S. enterica serovar Enteritidis (SE8743). To investigate the molecular basis for the RNI/ROI resistance of S. enterica serovar Enteritidis, we transformed a genomic DNA library of SE2472 into SE8743. A plasmid clone conferred upon SE8743 enhanced resistance to ASN, GSNO, and H(2)O(2). The DNA insert in the clone encoded ArcA, a global regulator. An arcA mutant of SE2472 was constructed and was found to be more susceptible to GSNO and hydrogen peroxide but not more susceptible to ASN than wild-type SE2472. The susceptibility of the arcA mutant to GSNO and H(2)O(2) was complemented by a plasmid harboring arcA. The coding sequence of the arcA gene in SE2472 and the coding sequence of the arcA gene in SE8743 were identical, suggesting that the difference in resistance to RNI/ROI maybe due to the activity of genes regulated by ArcA. No significant difference in virulence between the wild type and the arcA mutant of SE2472 was observed in mice. These observations show that arcA is essential for resistance of S. enterica serovar Enteritidis to nitrosative and oxidative stress. However, additional genetic loci may contribute to the resistance to RNI/ROI and unusually high virulence for mice of SE2472.

Topics: Animals; Bacterial Outer Membrane Proteins; Cloning, Molecular; Culture Media; Detergents; Disease Models, Animal; DNA, Bacterial; Drug Resistance, Bacterial; Escherichia coli Proteins; Gene Library; Genetic Testing; Heating; Hydrogen Peroxide; Hydrogen-Ion Concentration; Mice; Mice, Inbred BALB C; Mice, Inbred C3H; Mutagenesis; Nitric Oxide Donors; Nitrogen; Oxidants; Plasmids; Reactive Oxygen Species; Repressor Proteins; S-Nitrosoglutathione; Salmonella enteritidis; Salmonella Infections; Sequence Analysis, DNA; Sodium Chloride; Sodium Dodecyl Sulfate; Sodium Nitrite; Virulence

Interaction studies using hydrogen NMR spin-lattice relaxation time measurements of a series of five antiparasitic guanyl hydrazones with SDS and cetyl trimethylammonium bromide micelles are used as a simple model for the interaction of these compounds with the cell membrane of Trypanosoma cruzi. The results show that the activity of the compounds is related to their capacity to selectively interact with anionic micelles, which reinforces the hypothesis that the mechanism of action of these compounds is related to their selective interaction with the negatively charged parasite membrane.

Topics: Animals; Anti-Bacterial Agents; Cations; Cell Membrane; Cetrimonium; Cetrimonium Compounds; Chagas Disease; Disease Models, Animal; Guanine; Hydrazones; Magnetic Resonance Spectroscopy; Micelles; Models, Molecular; Sodium Dodecyl Sulfate; Trypanosoma cruzi

The accumulation of amyloid beta protein (Abeta) in the Tg2576 mouse model of Alzheimer's disease (AD) was evaluated by ELISA, immunoblotting, and immunocytochemistry. Changes in Abeta begin at 6-7 months as SDS-insoluble forms of Abeta42 and Abeta40 that require formic acid for solubilization appear. From 6 to 10 months, these insoluble forms increase exponentially. As insoluble Abeta appears, SDS-soluble Abeta decreases slightly, suggesting that it may be converting to an insoluble form. Our data indicate that it is full-length unmodified Abeta that accumulates initially in Tg2576 brain. SDS-resistant Abeta oligomers and most Abeta species that are N-terminally truncated or modified develop only in older Tg2576 mice, in which they are present at levels far lower than in human AD brain. Between 6 and 10 months, when SDS-insoluble Abeta42 and Abeta40 are easily detected in every animal, histopathology is minimal because only isolated Abeta cores can be identified. By 12 months, diffuse plaques are evident. From 12 to 23 months, diffuse plaques, neuritic plaques with amyloid cores, and biochemically extracted Abeta42 and Abeta40 increase to levels like those observed in AD brains. Coincident with the marked deposition of Abeta in brain, there is a decrease in CSF Abeta and a substantial, highly significant decrease in plasma Abeta. If a similar decline occurs in human plasma, it is possible that measurement of plasma Abeta may be useful as a premorbid biomarker for AD.

Topics: Aging; Alzheimer Disease; Amyloid beta-Peptides; Amyloid beta-Protein Precursor; Animals; Biomarkers; Brain; Brain Chemistry; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Female; Formates; Humans; Immunoblotting; Immunohistochemistry; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Organ Specificity; Plaque, Amyloid; Sodium Dodecyl Sulfate

The influence of sodium lauryl sulfate (SLS) on the efficacies of topical gel formulations of foscarnet against herpes simplex virus type 1 (HSV-1) cutaneous infection has been evaluated in mice. A single application of the gel formulation containing 3% foscarnet given 24 h postinfection exerted only a modest effect on the development of herpetic skin lesions. Of prime interest, the addition of 5% SLS to this gel formulation markedly reduced the mean lesion score. The improved efficacy of the foscarnet formulation containing SLS could be attributed to an increased penetration of the antiviral agent into the epidermis. In vitro, SLS decreased in a concentration-dependent manner the infectivities of herpesviruses for Vero cells. SLS also inhibited the HSV-1 strain F-induced cytopathic effect. Combinations of foscarnet and SLS resulted in subsynergistic to subantagonistic effects, depending on the concentration used. Foscarnet in phosphate-buffered saline decreased in a dose-dependent manner the viability of cultured human skin fibroblasts. This toxic effect was markedly decreased when foscarnet was incorporated into the polymer matrix. The presence of SLS in the gel formulations did not alter the viabilities of these cells. The use of gel formulations containing foscarnet and SLS could represent an attractive approach to the treatment of herpetic mucocutaneous lesions, especially those caused by acyclovir-resistant strains.

Topics: Administration, Topical; Animals; Antiviral Agents; Cell Survival; Chemistry, Pharmaceutical; Chlorocebus aethiops; Disease Models, Animal; Drug Synergism; Female; Foscarnet; Herpes Simplex; Herpesvirus 1, Human; Humans; Mice; Mice, Hairless; Skin Absorption; Skin Diseases, Viral; Sodium Dodecyl Sulfate; Surface-Active Agents; Vero Cells

To evaluate the feasibility of mucosal immunization against Pneumocystis carinii (Pc) experimental infection, female BALB/c mice were intranasally immunized three times with soluble Pc antigens plus cholera toxin fraction B (Pc-CTB); control groups received either Pc antigen, CTB, or phosphate-buffered saline (PBS) alone. Two weeks after the last immunization, five animals from each group were sacrificed, and cellular and humoral immune responses were evaluated. The remaining five mice were CD4 depleted using a monoclonal antibody against mouse CD4 and inoculated with viable Pc. Significantly higher specific lymphoproliferative responses from tracheobronchial lymph node cells, immunoglobulin M (IgM) and IgG antibody levels in serum, and bronchoalveolar lavage (BAL)-derived IgA antibody concentrations were observed in the Pc-CTB group of mice relative to control groups (P < 0.01). Five weeks after challenge, no Pc organisms were observed in the lung smears of the Pc-CTB group, while the animals receiving antigen, adjuvant, or PBS had progressively higher numbers of Pc microorganisms. By Western blot analysis, a strongly reactive 55- to 60-kDa antigen was recognized by BAL IgA and by serum IgG. In summary, mucosal immunization elicited specific cellular and humoral immune responses and protected against Pc lung infection after immunosuppression.

Topics: Administration, Intranasal; Animals; Antibodies, Bacterial; Blotting, Western; Bronchoalveolar Lavage; CD4-Positive T-Lymphocytes; Disease Models, Animal; Electrophoresis, Polyacrylamide Gel; Feasibility Studies; Female; Fungal Vaccines; Lymphocyte Depletion; Mice; Mice, Inbred BALB C; Pneumocystis; Pneumonia, Pneumocystis; Sodium Dodecyl Sulfate; Vaccination

There is limited information concerning the nature and extent of the immune response to the virulence determinants of Yersinia pestis during the course of plague infection. In this study, we evaluated the humoral immune response of mice that survived lethal Y. pestis aerosol challenge after antibiotic treatment. Such a model may replicate the clinical situation in humans and indicate which virulence determinants are expressed in vivo. Immunoglobulin G enzyme-linked immunosorbent assay and immunoblotting were performed by using purified, recombinant antigens including F1, V antigen, YpkA, YopH, YopM, YopB, YopD, YopN, YopE, YopK, plasminogen activator protease (Pla), and pH 6 antigen as well as purified lipopolysaccharide. The major antigens recognized by murine convalescent sera were F1, V antigen, YopH, YopM, YopD, and Pla. Early treatment with antibiotics tended to reduce the immune response and differences between antibiotic treatment regimens were noted. These results may indicate that only some virulence factors are expressed and/or immunogenic during infection. This information may prove useful for selecting potential vaccine candidates and for developing improved serologic diagnostic assays.

Topics: Animals; Anti-Infective Agents; Antibodies, Bacterial; Antigens, Bacterial; Bacterial Outer Membrane Proteins; Disease Models, Animal; Electrophoresis, Polyacrylamide Gel; Enzyme-Linked Immunosorbent Assay; Female; Immunoblotting; Immunoglobulin G; Mice; Ofloxacin; Plague; Sodium Dodecyl Sulfate; Time Factors; Yersinia pestis

The class II molecules of the diabetes-prone NOD mice, I-Ag7, showed very limited amounts of stable form when analyzed by SDS-PAGE. We included the analysis of spleen B cells and B lymphoma cells transfected with I-Ag7 genes. Early during bio-synthesis there was invariant chain binding to the alpha beta-chains. Examination of APCs from F1 mice (NOD x C57BL/6) indicated that the same APC expressed high levels of unstable I-Ag7 and normal amounts of stable class II molecules compared with the other haplotype (I-Ab). The half-life of I-Ag7-peptide complexes on the cell surface of APC was significantly shorter than that of other class II haplotypes. Direct biochemical demonstration of peptide interactions with I-Ag7 was difficult to demonstrate. In T cell assays, the immunogenic peptides, including the diabetogenic Ag, were rapidly lost when peptide-pulsed APCs were washed free of peptide. We hypothesize that the weak and unstable peptide-binding property of I-Ag7 molecules does not favor the elimination or inactivation of autoreactive T cells.

Topics: Amino Acid Sequence; Animals; Antigen Presentation; Autoantigens; Autoimmune Diseases; Base Sequence; Crosses, Genetic; Diabetes Mellitus, Type 1; Disease Models, Animal; Female; Genes, MHC Class II; Haplotypes; Histocompatibility Antigens Class II; Hybridomas; Islets of Langerhans; Isoantigens; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Inbred CBA; Mice, Inbred NOD; Mice, SCID; Molecular Sequence Data; Mutagenesis, Site-Directed; Peptide Fragments; Sodium Dodecyl Sulfate

Topics: Adhesives; Adult; Animals; Body Water; Dermatitis, Irritant; Disease Models, Animal; Epidermis; Female; Galvanic Skin Response; Humans; Mice; Mice, Hairless; Occlusive Dressings; Polypropylenes; Polytetrafluoroethylene; Sodium Dodecyl Sulfate; Species Specificity

Topics: Alopecia; Animals; Body Water; Dermatitis, Irritant; Disease Models, Animal; Drug Evaluation, Preclinical; Erythema; Female; Histamine Release; Industrial Oils; Intradermal Tests; Irritants; Male; Nicotinic Acids; Ointments; Patch Tests; Permeability; Sodium Dodecyl Sulfate; Sodium Hydroxide; Swine; Swine, Miniature; Toluene

Low levels of high-density lipoproteins (HDLs) may constitute an independent risk factor that may be as important as elevated low-density lipoproteins (LDLs) in coronary artery disease (CAD). Concentrations and distributions of lipids, apolipoprotein (apo) B, and apoA-I in the plasma and lipoprotein subfractions of two groups of swine, one with familial hypercholesterolemia (FHC) and the other with diet-induced hypercholesterolemia (DHC), were examined. Normolipidemic (NL) animals served as controls. All pigs carried the Lpb5 apoB mutation, which is known to influence the formation of atherosclerotic lesions. Mean concentrations of serum total cholesterol in NL, DHC, and FHC were 80.0 +/- 9.3, 774.3 +/- 54.5, and 316.5 +/- 36.1 mg/dL, respectively; HDL cholesterol (HDL-C), 33.5 +/- 1.9, 137.0 +/- 9.9, and 22.3 +/- 2.2 mg/dL; triglycerides, 33.0 +/- 16.3, 40.3 +/- 11.7, and 56.8 +/- 7.2 mg/dL; apoB, 35.7 +/- 3.1, 142.0 +/- 4.8, and 169.3 +/- 13.9 mg/dL; and apoA-I, 62.4 +/- 9.3, 170.9 +/- 6.9, and 42.6 +/- 4.8 mg/dL. The distributions of total cholesterol, apoB, and apoA-I in plasma lipoprotein subfractions were also examined. Compared with NL, FHC had fourfold and 4.7-fold increases in total cholesterol and apoB, respectively, distributed in the lower densities (d < 1.043 g/mL), and low HDL-C and apoA-I levels, resulting in a high total cholesterol/HDL-C ratio (14.4:1) and elevated triglyceride levels. DHC was characterized by 10-fold and fourfold increases in total cholesterol and apoB, respectively, resulting in an LDL particle highly enriched in cholesterol, a fourfold increase of HDL-C, an almost threefold increase in apoA-I, and a normal triglyceride level.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Apolipoprotein A-I; Apolipoproteins B; Cholesterol; Diet; Disease Models, Animal; Electrophoresis, Polyacrylamide Gel; Gels; Hypercholesterolemia; Hyperlipoproteinemia Type II; Immunoelectrophoresis; Lipids; Lipoproteins; Male; Sepharose; Sodium Dodecyl Sulfate; Swine

Vipera berus is widely distributed throughout the northern part of Europe and Asia. Characterization of several toxic effects of its venom in the mouse, as well as of in vitro enzymatic activities was performed. Vipera berus venom displayed in vitro proteolytic, fibrinolytic, anticoagulant, and phospholipase A2 activities. The i.p. LD50 of the venom for Swiss mice was 0.86 micrograms/g (95% confidence limits 0.71-1.01 microgram/g). Significant local tissue-damaging effects, including edema, hemorrhage and myonecrosis, were observed. The local edema was characterized by rapid onset, reaching a maximum after 0.5-1 hr, and with dose-dependent persistence. The hemorrhagic potency was measured by a skin test, giving a minimum hemorrhagic dose value of 3.2 micrograms. The venom also induced a moderate local myonecrosis, evidenced by histological evaluation of injected tissue (gastrocnemius), and by biochemical parameters (increase of plasma creatine kinase activity, and decrease of muscle residual MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide)-reducing activity). Characterization of the venom by SDS-polyacrylamide gel electrophoresis revealed 10 (reduced) or 11 (unreduced) main protein bands, which were further analyzed in relation to mol. wt and relative concentration by densitometry. A rabbit antiserum to V. berus venom recognized all main venom bands by immunoblotting. This antiserum cross-reacted to a variable extent with several crotaline venoms, as assessed by enzyme immunoassay.

Topics: Animals; Antibodies; Antigens; Cross Reactions; Crotalid Venoms; Disease Models, Animal; Dose-Response Relationship, Drug; Edema; Electrophoresis, Polyacrylamide Gel; Immunoblotting; Lethal Dose 50; Mice; Peptide Hydrolases; Rabbits; Sodium Dodecyl Sulfate; Viper Venoms

The purpose of this study was to develop a rapid procedure for the preparation of melanin with a specific, highly uveitogenic activity.. A crude melanosome fraction was isolated from bovine choroids (containing remnants of adhering retinal pigment epithelium). The fraction was extracted with hot 2% sodium dodecyl sulfate, and Lewis rats were immunized with the purified melanin, using pertussis toxin as coadjuvant.. The purified melanin was free from pathogenic photoreceptor antigens and other accompanying or adsorbed proteins. It was able to evoke severe, acute, anterior uveitis with the typical characteristics of experimental autoimmune anterior uveitis (EAAU; without retinitis or pinealitis), even at the level of 1 micrograms melanin protein.. The rapidly prepared ocular melanin exhibits the same qualities as purified choroidal or retinal pigment melanins obtained by much more laborious procedures (which also deliver other subcellular fractions for investigation). It is suitable for the study of the immunopathogenesis of EAAU, which is a new model for human acute anterior uveitis.

Topics: Acute Disease; Animals; Cattle; Choroid; Disease Models, Animal; Eye Proteins; Melanins; Melanocytes; Rats; Rats, Inbred Lew; Sodium Dodecyl Sulfate; Uveitis, Anterior

We observed hydrocortisone and benzoic acid absorption in relation to experimentally induced in vivo damaged skin models in the hairless guinea pig. Radioactivity of the drugs in urine was calculated as absorbed dose. Both drugs have different patterns of excretion in urine. Damaging the skin abolished some barrier function and increased the absorption of both model drugs. With cellophane-tape-stripped skin, the absorption was increased 3 times and 2 times for each drug, respectively. Irritation with 2% sodium lauryl sulfate increased absorption by a ratio of 2-4 times. Defatting with chloroform/methanol (2:1) mixture increased absorption to the greatest extent (5- and 2.7-fold). The possible mechanism of a delipidization effect was considered in view of a visible skin lesion and inflammatory reaction. Precautions are proposed for those with damaged/diseased skin in dealing with topical medications or handling solvents.

Topics: Administration, Topical; Animals; Benzoates; Benzoic Acid; Disease Models, Animal; Female; Guinea Pigs; Hydrocortisone; Injections, Intraperitoneal; Skin Absorption; Skin Diseases; Sodium Dodecyl Sulfate

Heymann nephritis is an experimental auto-immune glomerulonephritis, closely resembling human epimembranous nephritis, which is induced by identified antigens in the brush border membranes of kidney proximal tubules. The hallmark of the disease is the accumulation of immune deposits in a granular pattern in the lamina rara externa of the glomerular basement membrane. We have established that a large membrane glycoprotein with an apparent molecular weight of 330 kDal (pg 330) is the pathogenic antigen. By means of immunohistochemistry, using mono- and polyclonal anti-pg 330 IgG we found that gp 330 is present in the cell membranes of glomerular epithelial cells and that it is concentrated there in coated pits (specialized areas off the cell membrane which play a key role in receptor mediated endocytosis for ligands such as insulin and others). On the basis of these findings we propose the following mechanism of formation of an immune deposit: (1) "In-situ" formation of immune complexes of gp 330 and anti-gp 330 IgG; (2) shedding of the immune complexes into the basement membrane and (3) crosslinking of the immune complexes into the basement membrane. This scheme could be a general mechanism by which immune deposits are formed also in various other auto-immune diseases.

Topics: Animals; Antigen-Antibody Complex; Antigens, Surface; Autoimmune Diseases; Basement Membrane; Disease Models, Animal; Electrophoresis, Polyacrylamide Gel; Glomerulonephritis; Glycoproteins; Heymann Nephritis Antigenic Complex; Immunoenzyme Techniques; Rats; Sodium Dodecyl Sulfate

An animal model (the rabbit) was used to define which of 8 chemicals caused pustule formation on topical application. Large occlusive chambers (diameter 12 mm), petrolatum as the vehicle and wrapping contributed to efficient occlusion and pustulation. Sodium lauryl sulfate and mecuric chloride gave reproducible results and clear dose-responses indicating that this pustulation is an expression of primary irritancy. Ammonium fluoride pustulation was not reproducible; croton oil pustules were more difficult to evaluate due to simultaneous erythema and edema. Sodium arsentate, nickel sulfate and potassium iodide pustules developed at sites where the skin barriers had been damaged by a stab injury. Benzalkonium chloride caused yellow staining and edema but not pustules. Because of lack of epidemiologic data, we do not know how frequently similar findings occur in man.

Topics: Ammonium Compounds; Animals; Arsenates; Benzalkonium Compounds; Croton Oil; Disease Models, Animal; Dose-Response Relationship, Drug; Fluorides; Irritants; Mercuric Chloride; Mercury; Nickel; Potassium Iodide; Quaternary Ammonium Compounds; Rabbits; Skin; Skin Diseases; Sodium Dodecyl Sulfate; Suppuration

The status of efforts to develop experimental models for drug photosensitivity reactions in small mammals is reviewed. Tests which are practical and also have a high predictive value in determining photosensitivity hazards to man are the goal of this research. The various animal model systems which have been used are evaluated with respect to these goals.

Topics: Animals; Cells, Cultured; Disease Models, Animal; Freund's Adjuvant; Guinea Pigs; Humans; Mice; Photosensitivity Disorders; Rabbits; Skin; Sodium Dodecyl Sulfate; Swine; Ultraviolet Rays

Extracts of human peripheral blood polymorphonuclear leukocyte granules, and two purified proteases derived from such extracts, an elastase and a chymotrypsin-like enzyme, degrade isolated bovine nasal cartilage proteoglycan at neutral pH. Viscosity studies indicate that the leukocyte granule extracts lack hyaluronidase activity and that their degradative effect on proteoglycan at physiological pH is due entirely to proteolytic action. Sepharose 4B gel chromatography and SDS-polyacrylamide gel electrophoresis of proteoglycan fractions treated with leukocyte granule enzymes at pH 7.0 indicate that they degrade one of the proteoglycan link proteins, release a fragment from the hyaluronic acid-binding portion of the proteoglycan subunit core protein, and break down the remainder of the proteoglycan subunit molecule into peptide fragments with varying numbers of chondroitin sulfate chains. Immunodiffusion studies indicate that the antigenic determinants of the proteoglycan subunit core protein and the link proteins survive treatment with granule proteases. Similar degradation of human articular cartilage proteoglycan by granule neutral proteases can be presumed to occur, in view of the similarity of structure of human articular and bovine nasal cartilage proteoglycans. The release of granule enzymes in the course of neutrophil-mediated inflammation can thus result in the degradation of cartilage matrix proteoglycan, leading to cartilage destruction and joint injury.

Topics: Animals; Arthritis; Cartilage, Articular; Cattle; Chemical Phenomena; Chemistry; Chondroitin Sulfates; Chromatography, Gel; Chymotrypsin; Cytoplasmic Granules; Disease Models, Animal; Electrophoresis, Polyacrylamide Gel; Glycosaminoglycans; Humans; Immunodiffusion; Joint Diseases; Leukocytes; Nasal Septum; Pancreatic Elastase; Proteoglycans; Sodium Dodecyl Sulfate; Viscosity