hydroxyethylcellulose and Disease-Models--Animal

Massive bleeding control and anti-infection are the major challenges for urgent trauma with deep and noncompressible hemorrhage in both clinic and battlefield. Inspired by the coordinated primarily blood clot formation and secondly coagulation cascade activation in natural hemostasis process, an injectable, quaternized hydroxyethyl cellulose/mesocellular silica foam (MCF) hydrogel sponge (QHM) for both hemorrhage control and antibacterial activities were prepared via one-pot radical graft copolymerization. The as-prepared QHMs exhibited instant water-triggered expansion and superabsorbent capacity and thereby effectively facilitated blood components concentration. Moreover, the QHM1 with appropriate amount of MCF (9.82 w/w %) could further activate the coagulation factors. Synergistically, the QHM1 could reduce the plasma clotting time to 59 ± 4% in vitro and showed less blood loss than commercially available hemostatics in vivo noncompressible hemorrhage models of lethal rabbit-liver defect. Furthermore, the QHM with a quaternary ammonium groups density of 2.732 mmol/g exhibited remarkable antibacterial activities and excellent cytocompatibility. With the efficient hemostasis efficacy and excellent antibacterial behavior, QHM dramatically facilitated the wound healing in a full-thickness skin defect model in vivo. Thus, this QHM represents a promising hemostatic in more widespread clinical application.

Topics: Animals; Anti-Bacterial Agents; Bandages; Cell Line; Cellulose; Disease Models, Animal; Hemostasis; Hemostatics; Hydrogels; Mice; Rabbits; Skin; Wound Healing; Wounds and Injuries

To investigate the effect of a new soluble fiber, namely cationic hydroxyethyl cellulose (cHEC), on weight loss and metabolic disorders associated with obesity using a high-fat diet-induced obese mouse model.. Obese male C57BL/6J (B6) mice were fed high-fat (60% kcal) diets supplemented with cHEC for 5 weeks. Body weight, energy intake, mesenteric adipose and liver weights, plasma cholesterol, plasma insulin, glucose, adiponectin, and leptin were assessed to determine the effects of cHEC. Hepatic and fecal lipids were also analyzed to investigate the effect of cHEC on lipid absorption and metabolism.. Supplementation of the high-fat diet with cHEC resulted in significant weight loss in obese mice. In addition, significant decreases were seen in mesenteric adipose and liver weights, as well as concentrations of plasma cholesterol and hepatic lipids. A significant improvement in glucose homeostasis, insulin sensitivity, and leptin concentrations were observed at 4% cHEC. Moreover, increases in fecal excretion of total bile acids, sterols, and fats indicated altered fat absorption when cHEC was supplemented in the diet.. We have shown in the present study that cHEC reduces body weight, improves insulin sensitivity, and prevents the development of metabolic syndrome. Furthermore, the effects of cHEC on glucose and lipid homeostasis in B6 mice are mediated by improvements in leptin sensitivity resulting from reduced fat absorption.

Topics: Adiponectin; Animals; Cellulose; Disease Models, Animal; Glucose; Insulin; Leptin; Lipids; Male; Mice; Mice, Inbred C57BL; Obesity; Weight Gain

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

Microbicides must protect against STD pathogens without causing unacceptable toxic effects. Microbicides based on nonoxynol-9 (N9) and other detergents disrupt sperm, HSV and HIV membranes, and these agents are effective contraceptives. But paradoxically N9 fails to protect women against HIV and other STD pathogens, most likely because it causes toxic effects that increase susceptibility. The mouse HSV-2 vaginal transmission model reported here: (a) Directly tests for toxic effects that increase susceptibility to HSV-2, (b) Determines in vivo whether a microbicide can protect against HSV-2 transmission without causing toxicities that increase susceptibility, and (c) Identifies those toxic effects that best correlate with the increased HSV susceptibility.. Susceptibility was evaluated in progestin-treated mice by delivering a low-dose viral inoculum (0.1 ID50) at various times after delivering the candidate microbicide to detect whether the candidate increased the fraction of mice infected. Ten agents were tested - five detergents: nonionic (N9), cationic (benzalkonium chloride, BZK), anionic (sodium dodecylsulfate, SDS), the pair of detergents in C31G (C14AO and C16B); one surface active agent (chlorhexidine); two non-detergents (BufferGel, and sulfonated polystyrene, SPS); and HEC placebo gel (hydroxyethylcellulose). Toxic effects were evaluated by histology, uptake of a 'dead cell' dye, colposcopy, enumeration of vaginal macrophages, and measurement of inflammatory cytokines.. A single dose of N9 protected against HSV-2 for a few minutes but then rapidly increased susceptibility, which reached maximum at 12 hours. When applied at the minimal concentration needed for brief partial protection, all five detergents caused a subsequent increase in susceptibility at 12 hours of approximately 20-30-fold. Surprisingly, colposcopy failed to detect visible signs of the N9 toxic effect that increased susceptibility at 12 hours. Toxic effects that occurred contemporaneously with increased susceptibility were rapid exfoliation and re-growth of epithelial cell layers, entry of macrophages into the vaginal lumen, and release of one or more inflammatory cytokines (Il-1beta, KC, MIP 1alpha, RANTES). The non-detergent microbicides and HEC placebo caused no significant increase in susceptibility or toxic effects.. This mouse HSV-2 model provides a sensitive method to detect microbicide-induced toxicities that increase susceptibility to infection. In this model, there was no concentration at which detergents provided protection without significantly increasing susceptibility.

Topics: Animals; Cellulose; Detergents; Disease Models, Animal; Drug-Related Side Effects and Adverse Reactions; Female; Herpes Genitalis; Herpesvirus 2, Human; Humans; Mice; Nonoxynol; Polystyrenes; Surface-Active Agents; Vagina

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

There is increasing evidence that cells of the epithelial root sheath synthesize enamel matrix proteins and that these proteins play a fundamental role in the formation of acellular cementum, the key tissue in the development of a functional periodontium. The purpose of the present study was to explore the effect of locally applied enamel matrix and different protein fractions of the matrix on periodontal regeneration in a buccal dehiscence model in monkeys. Buccal, mucoperiosteal flaps were raised from the canine to the 1st molar on each side of the maxilla. The buccal alveolar bone plate, the exposed periodontal ligament and cementum were removed. Various preparations of porcine enamel matrix with or without vehicles were applied before the flaps were repositioned and sutured. After 8 weeks, the healing was evaluated in the light microscope, and morphometric comparisons were made. Application of homogenized enamel matrix or an acidic extract of the matrix containing the hydrophobic, low molecular weight proteins, amelogenins, resulted in an almost complete regeneration of acellular cementum, firmly attached to the dentin and with collagenous fibers extending over to newly formed alveolar bone. After application of fractions obtained by neutral EDTA extraction containing the acidic, high molecular weight proteins of the enamel matrix, very little new cementum was formed and hardly any new bone. The results of the controls in which no test substance was applied before the repositioning of the flap, were very similar to those obtained with the EDTA extracted material. Propylene glycol alginate (PGA), hydroxyethyl cellulose and dextran were tried as vehicles for the enamel matrix preparations. Only PGA in combination with the amelogenin fraction resulted in significant regeneration of the periodontal tissues.

Topics: Alginates; Alveolar Bone Loss; Alveolar Process; Amelogenin; Animals; Cellulose; Collagen; Dental Cementum; Dental Enamel Proteins; Dentin; Dextrans; Disease Models, Animal; Epithelium; Macaca fascicularis; Molecular Weight; Osteogenesis; Periodontal Attachment Loss; Periodontal Diseases; Periodontium; Pharmaceutical Vehicles; Regeneration; Surgical Flaps; Swine; Tissue Extracts; Tooth Root