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- Ability of chitosan gels to disrupt bacterial biofilms and their applications in the treatment of bacterial vaginosis. [JOURNAL ARTICLE]
- J Pharm Sci 2013 May 20.
Recurrence of bacterial vaginosis is attributed to the inability of various formulations to disrupt bacterial biofilms. A negatively charged polysaccharide matrix coats the bacterial communities in the biofilm and restricts the penetration of antibiotics. Therefore, bacteria in the deeper segments of the biofilm persist and perpetuate the infection. In this study, we have tested the efficacy of two bioadhesive polymers, cationic chitosan and anionic polycarbophil, to disrupt Pseudomonas aeruginosa biofilms grown in the Center for Disease Control bioreactor as well as on the 96-well plates. The biofilms were treated with various concentrations of polycarbophil and chitosan at pH 4 or 6. Biofilm integrity following various treatments was evaluated by crystal violet stain and laser confocal microscopy employing Syto9 (live-cell stain) and propidium iodide (dead-cell stain). These studies demonstrated that chitosan gel disrupts the P. aeruginosa biofilm more effectively than does polycarbophil; and this effect is independent of the pH and charge densities on either polymers. © 2013 U.S. Government.
- The Acceptability, Feasibility, and Efficacy (Phase I/II Study) of the OVERcome (Olive Oil, Vaginal Exercise, and MoisturizeR) Intervention to Improve Dyspareunia and Alleviate Sexual Problems in Women with Breast Cancer. [JOURNAL ARTICLE]
- J Sex Med 2013 May 1.
INTRODUCTION:Almost half of breast cancer survivors experience chronic sexual problems. Despite the negative effects of dyspareunia on physical and overall quality of life, sexual dysfunction remains underreported and undertreated in clinical practice. This is likely due to the paucity of evidence-based interventions to improve sexual functioning.
AIM:The study aims to prospectively evaluate the acceptability, feasibility, and efficacy of a novel intervention (Olive Oil, Vaginal Exercise, and MoisturizeR [OVERcome]) to improve sexual problems following breast cancer treatment.
MAIN OUTCOME MEASURES:Dyspareunia, sexual functioning, quality of life, distress, and pelvic floor muscles (PFMs) functioning were evaluated.
METHODS:Twenty-five women with dyspareunia were instructed to perform pelvic floor muscle (PFM) relaxation exercises twice/day to prevent/manage PFM overactivity, apply a polycarbophil-based vaginal moisturizer three times/week to alleviate vaginal dryness, use olive oil as a lubricant during intercourse, and complete a weekly compliance diary. PFM relaxation training was administered by a physiotherapist at weeks 0 and 4, with follow-up at weeks 12 and 26. At each visit, women completed validated self-report questionnaires and the physiotherapist recorded objective measures of PFM functioning.
RESULTS:OVERcome resulted in significant improvements in dyspareunia, sexual function, and quality of life over time (all P < 0.001). PFM relaxation training was reported to be effective (P ≤ 0.001). Maximum benefits were observed at week 12. Most women rated PFM relaxation exercises (92%), vaginal moisturizer (88%), and olive oil (73%) as helpful, indicating that the intervention was acceptable. Unexpectedly, six cases (11%) of vaginal stenosis were noted during initial screening.
CONCLUSIONS:This novel intervention is acceptable to patients with demonstrated efficacy in improving dyspareunia and sexual function following breast cancer. Delivery of the OVERcome intervention appears feasible in a clinical setting, providing a potential treatment for this important clinical issue. The unexpected number of observed cases of stenosis further highlights the underreporting of sexual problems in this population, deserving further exploration. Juraskova I, Jarvis S, Mok K, Peate M, Meiser B, Cheah BC, Mireskandari S, and Friedlander M. The acceptability, feasibility, and efficacy (Phase I/II study) of the OVERcome (Olive oil, Vaginal Exercise, and moisturizeR) intervention to improve dyspareunia and alleviate sexual problems in women with breast cancer. J Sex Med **;**:**-**.
- The Influence of Recrystallized Caffeine on Water-Swellable Polymethacrylate Mucoadhesive Buccal Films. [JOURNAL ARTICLE]
- AAPS PharmSciTech 2013 Mar 2.
The aim of this work was to investigate the influence of particles on the properties of polymethacrylate films intended for buccal delivery. A solvent casting method was used with Eudragit RS and RL (ERS and ERL, respectively) as film-forming rate-controlling polymers, with caffeine as a water-soluble model drug. The physicochemical properties of the model films for a series of formulations with increasing concentrations of caffeine were determined in terms of morphology, mechanical and mucoadhesive properties, drug content uniformity, and drug release and associated kinetics. Typically regarded as non-mucoadhesive polymers, ERS and mainly ERL, were found to be good mucoadhesives, with ERL01 exhibiting a work of mucoadhesion (WoA) of 118.9 μJ, which was about five to six times higher than that observed for commonly used mucoadhesives such as Carbopol(®) 974P (C974P, 23.9 μJ) and polycarbophil (PCP, 17.4 μJ). The mucoadhesive force for ERL01 was found to be significantly lower yet comparable to C974P and PCP films (211.1 vs. 329.7 and 301.1 mN, respectively). Inspection of cross-sections of the films indicated that increasing the concentration of caffeine was correlated with the appearance of recrystallized agglomerates. In conclusion, caffeine agglomerates had detrimental effects in terms of mucoadhesion, mechanical properties, uniformity, and drug release at large particle sizes. ERL series of films exhibited very rapid release of caffeine while ERS series showed controlled release. Analysis of release profiles revealed that kinetics changed from a diffusion controlled to a first-order release mechanism.
- Development and characterization of chitosan-polycarbophil interpolyelectrolyte complex-based 5-fluorouracil formulations for buccal, vaginal and rectal application. [Journal Article]
- Daru 2012; 20(1):67.
ABSTRACT:Precipitation method is employed for preparation of chitosan and polycarbophil interpolyelectrolyte complex (IPEC) followed by characterization with Fourier transform infrared spectroscopy (FT-IR), Differential Scanning calorimeter (DSC) and X-ray Diffraction (XRD). 5-FU tablets were prepared by direct compression using IPEC. Six formulations were prepared with IPEC alone and in combination with chitosan, polycarbophil and Sodium deoxycholate. The formulations were tested for drug content, hardness, friability, weight variation, thickness, swelling studies, in vitro drug release (buccal, vaginal and rectal pH), ex vivo permeation studies, mucoadhesive strength and in vivo studies.FT-IR studies represent the change in spectra for the IPEC than single polymers.DSC study represents the different thermo gram for chitosan, polycarbophil and IPEC whereas in X-ray diffraction, crystal size alteration was observed. Formulations containing IPEC showed pH independent controlled 5-FU without an initial burst release effect in buccal, vaginal and rectal pH. Furthermore, F4 formulations showed controlled release 5-FU with highest bioadhesive property and satisfactory residence in both buccal and vaginal cavity of rabbit. 3% of SDC in formulation F6 exhibited maximum permeation of 5-FU.The suitable combination of IPEC, chitosan and polycarbophil demonstrated potential candidate for controlled release of 5-FU in buccal, vaginal and rectal pH with optimum swelling approaching zero order release.
- Rheological, mechanical, and bioadhesive behavior of hydrogels to optimize skin delivery systems. [JOURNAL ARTICLE]
- Drug Dev Ind Pharm 2012 Dec 6.
Background:Hydrogels are widely used for cutaneous formulations; thereby comparing the bioadhesive properties of polymers with a view to prolong the residence time of topical drugs on the skin would be very useful to design novel topical drug delivery systems.
Aim:The objective of this study was to correlate data from rheological studies and texture profile analysis, with bioadhesion on the skin.
Methods:Polyacrylic acid polymers used were carbomer homopolymer type A (C971) and type B (C974), and polycarbophil (PP) dispersed in water at various concentrations (0.1, 0.5, 1.0, 1.5, 2.0, 3.0, 5.0%, w/v). Rheological, texture, and bioadhesive properties were determined to compare the hydrogels.
Results:Rheological analysis showed that all samples exhibited pseudoplastic behavior with thixotropy. Texture profile analysis showed that compressibility, hardness, and adhesiveness of the hydrogels were dependent on the polymer concentration, and the cohesion values were high. Bioadhesion of C974 and PP at 0.5 and 2% was of the same magnitude, while all samples of C971 had lower values. The bioadhesion of 5% C974 was the highest, while that 5% PP was lower, possibly because PP showed the greatest hardness and this rigidity may decrease the interaction of the polymer with the skin.
Conclusion:A comprehensive comparative rheological and textural analyses of several polymers for topical systems were undertaken in terms of their bioadhesion. Therefore, it is possible to conclude that these polymers can be used for optimization of drug delivery systems on the skin.
- Safety of repeated topical ocular administration of a polycarbophil-based formulation in several models of ocular surgery in rabbits. [Journal Article, Research Support, Non-U.S. Gov't]
- J Cataract Refract Surg 2012 Apr; 38(4):696-704.
To evaluate the safety of the polycarbophil-based formulation Durasite in rabbits when administered chronically to intact eyes and acutely to eyes compromised by a corneal epithelial defect, penetrating corneal incision, or laser in situ keratomileusis (LASIK) flap. The rheological properties were evaluated to characterize the behavior of the formulation on the ocular surface.Bausch & Lomb, Rochester, New York, USA.Experimental study.Intact eyes of albino rabbits received polycarbophil (0.6% or 1.3%) 3 times a day for 1 year. The compromised models using polycarbophil 0.9% were an epithelial defect, penetrating corneal incision, or LASIK flap. Eyes with the epithelial defects were dosed 10 times for 24 hours and then 2 times a day for 2 days, and the defect was monitored with fluorescein. The incision or LASIK eyes were dosed 4 times a day for 11 days starting the day before surgery, with 1 drop just before the surgical procedure. The eyes were examined microscopically. The rheological properties were evaluated using a controlled-stress rheometer with a synthetic tear fluid.No adverse ocular or systemic effects were observed with polycarbophil after chronic administration. In the compromised models, there were no adverse effects of the polycarbophil. There was no evidence of an anterior chamber reaction or qualitative effects on the corneal endothelium. Rheologically, the polycarbophil-based formulation behaved as a sheer-thinning fluid under physical conditions similar to the ocular surface.Results suggest that the polycarbophil-based formulation, like other shear-thinning formulations, is safe to use in topical ophthalmic pharmaceutical products indicated for chronic use and for treatment of conditions with compromise of the ocular surface.
- Formulation and optimization of mucoadhesive nanodrug delivery system of acyclovir. [Journal Article]
- J Young Pharm 2011 Oct; 3(4):275-83.
Acyclovir is an antiviral drug used for the treatment of herpes simplex virus infections, with an oral bioavailability of only 10-20% [limiting absorption in gastrointestinal tract to duodenum and jejunum] and half-life of about 3 h, and is soluble only at acidic pH (pKa 2.27). Mucoadhesive polymeric nanodrug delivery systems of acyclovir have been designed and optimized using 2(3) full factorial design. Poly (lactic-co-glycolic acid) (PLGA) (50:50) was used as the polymer along with polycarbophil (Noveon AA-1) as the mucoadhesive polymer and pluronic F68 as the stabilizer. From the preliminary trials, the constraints for independent variables X(1) (amount of PLGA), X(2) (amount of pluronic F68) and X(3) (amount of polycarbophil) have been fixed. The dependent variables that were selected for study were particle size (Y(1)), % drug entrapment (Y(2)) and % drug release in 12 h (Y(3)). The derived polynomial equations were verified by check point formulation. The application of factorial design gave a statistically systematic approach for the formulation and optimization of nanoparticles with the desired particle size, % drug release and high entrapment efficiency. Drug: Polymer ratio and concentration of stabilizer were found to influence the particle size and entrapment efficiency of acyclovir-loaded PLGA nanoparticles. The release was found to follow Fickian as well as non-Fickian diffusion mechanism with zero-order drug release for all batches. In vitro intestinal mucoadhesion of nanoparticles increased with increasing concentration of polycarbophil. These preliminary results indicate that acyclovir-loaded mucoadhesive PLGA nanoparticles could be effective in sustaining drug release for a prolonged period.
- Preparation and characterization of spray-dried mucoadhesive microspheres of ketorolac for nasal administration. [Journal Article]
- Curr Drug Deliv 2012 Mar; 9(2):205-18.
The objective of this investigation was to prepare mucoadhesive microspheres of ketorolac for nasal delivery to avoid gastrointestinal side effects of conventional dosage form. Mucoadhesive microspheres were prepared using carbopol, polycarbophil and chitosan as polymer by spray drying method. The process and formulation parameters were varied to study the effect on the yield and particle size. Microspheres were characterized for surface morphology, encapsulation efficiency, swelling behavior, mucoahesion properties, interaction studies using FTIR and DSC, in vitro drug release, ex vivo nasal cilio toxicity studies and in vivo anti-inflammatory and analgesic activity. Prepared microspheres were discrete, bulky, free flowing and showed an average encapsulation efficiency ranging from 79-92%. The results showed that the process parameters significantly affect the particle size (10.29-16.75 μm) and yield of microspheres (36.53-56.69%). Interaction studies revealed that there were no drug to polymer interactions. Prepared microspheres exhibited good swelling and mucoadhesion strength which confined the strong mucoadhesive property of microspheres. Ketorolac release from the microspheres was extended up to 8 h and exhibited fickian drug release kinetics with best fit to higuchi model. The drug loaded microspheres were found to be nontoxic to nasal mucosa. The anti-inflammatory and analgesic effects of formulation showed a significant increase (p < 0.05) in percent inhibition value of up to 8 h when compared with ketorolac. In conclusion, spray dried microspheres based on chitosan could be suitable nasal delivery system for the administration of ketorolac.
- Serial changes in cytokine expression in irritable bowel syndrome patients following treatment with calcium polycarbophil. [Journal Article]
- Hepatogastroenterology 2011 Sep-Oct; 58(110-111):1527-30.
Calcium polycarbophil improves abdominal symptoms in patients with irritable bowel syndrome (IBS). We examined cytokine expression in IBS patients before and after administration of calcium polycarbophil.A total of 24 IBS patients (13 diarrhea type, 11 constipation type; median age, 55 years) were enrolled. Serum levels of high sensitive C-reactive protein (CRP) and 17 cytokines (interleukin [IL]-1ß, -2, -4, 5, -6, -7, -8, -10, -12, -13 and -17; tumor necrosis factor-a [TNF-a]; interferon [IFN]-?; granulocyte colony-stimulating factor [G-CSF]; granulocyte macrophage colony-stimulating factor [GM-CSF]; macrophage inflammatory protein [MIP]-1ß; and macrophage chemo-attractant protein [MCP-1]) were simultaneously determined using a Bio-Plex suspension array system before and 12 weeks after administration of calcium polycarbophil 1,500-3,000mg/day.Serum MCP-1 levels in diarrhea type IBS patients were significantly higher than those in constipation type patients (p<0.05). In IBS patients, no significant changes in serum cytokine levels were observed following calcium polycarbophil administration. In constipation type patients, serum high sensitive CRP levels were significantly lower after treatment than before treatment.Decreases in serum high sensitive CRP levels following calcium polycarbophil treatment may be involved in the relief of abdominal symptoms in IBS patients; diarrhea type IBS is characterized by increased MCP-1 expression.
- Mucoadhesive platforms for targeted delivery to the colon. [Journal Article, Research Support, Non-U.S. Gov't]
- Int J Pharm 2011 Nov 25; 420(1):11-9.
A novel platform system, comprising a mucoadhesive core and a rapid release carrier, was designed for targeted drug delivery to the colon. Prednisolone pellets containing different carbomers, including Carbopol 971P, Carbopol 974P and Polycarbophil AA-1, with or without organic acids, were produced by extrusion-spheronization. Mucoadhesive pellets were coated with a new enteric double-coating system, which dissolves at pH 7. This system comprises an inner layer of partially neutralized Eudragit S and buffer salt and an outer coating of standard Eudragit S. A single layer of standard Eudragit S was also applied for comparison purposes. Dissolution of the coated pellets was assessed in USP II apparatus in 0.1N HCl followed by Krebs bicarbonate buffer pH 7.4. Visualization of the coating dissolution process was performed by confocal laser scanning microscopy using fluorescent markers in both layers. The mucoadhesive properties of uncoated, single-coated and-double coated pellets were evaluated ex vivo on porcine colonic mucosa. Mucoadhesive pellets coated with a single layer of Eudragit S release its cargo after a lag time of 120 min in Krebs buffer. In contrast, drug release from the double-coated mucoadhesive pellets was significantly accelerated, starting at 75 min. In addition, the mucoadhesive properties of the core of the double coated pellets were higher than those from single-coated pellets after the core had been exposed to the buffer medium. This novel platform technology has the potential to target the colon and overcome the variability in transit and harmonize drug release and bioavailability.