Platelet-camouflaged silver nanoparticle hydrogel accelerates wound healing in type 1 diabetic rats / 中国组织工程研究

BACKGROUND:Bacterial infections and impaired angiogenesis have been obstacles to diabetic wound healing,and the problem of multidrug resistance cannot be ignored,so there is an urgent need to find a new therapeutic strategy. OBJECTIVE:To prepare platelet-camouflaged silver nanoparticle hydrogel and observe its therapeutic effect on diabetic wounds. METHODS:(1)In vitro test:The ultra-small silver nanoparticles(usAgNPs)were obtained by reflux heating.usAgNPs-PL/CMC hydrogel was prepared by coupling it with platelets(PL)and adding it to the carboxymethyl cellulose(CMC)hydrogel.The microstructures,swelling properties,and mechanical properties of the hydrogel were characterized.The antibacterial activity of the hydrogel was tested by 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)5[(phenylamino)carbonyl]-2H-tetrazolium hydroxide method,reactive oxygen species method,bacterial biofilm method,and bacterial activity.(2)In vivo test:Forty SD rats were randomly divided into sham operation group,model group,CMC hydrogel group,usAgNPs/CMC hydrogel group,and usAgNPs-PL/CMC hydrogel group,with eight rats in each group.The type 1 diabetes model was established in the other four groups except the sham operation group.After successful model establishment,a skin wound(20 mm in diameter)deep to the fascia layer was made on the back of rats of the five groups.Rats in the sham operation group and model group were injected with normal saline.The rats in the CMC hydrogel group,usAgNPs/CMC hydrogel group,and usAgNPs-PL/CMC hydrogel group were implanted with the corresponding hydrogel,separately.The wound healing condition and healing quality were observed after 14 days of treatment. RESULTS AND CONCLUSION:(1)In vitro test:The usAgNPs-PL/CMC hydrogel had a uniform three-dimensional network structure,good mechanical properties,and strong water absorption ability,which could remarkably inhibit the growth of Escherichia coli and Staphylococcus aureus,and had a good inhibition and clearance effect on the formation of biofilms of the two bacteria,and had a good antibacterial ability.(2)In vivo test:After 14 days of treatment,the wounds of the usAgNPs-PL/CMC hydrogel group were basically closed.The wound healing rate was the highest,and the number of wound colonies was significantly lower than that of the model group.After 14 days of treatment,hematoxylin-eosin and Masson staining showed that the tissue structure of regenerated dermis appeared on the wounds of the usAgNPs-PL/CMC hydrogel group,usAgNPs/CMC hydrogel group,and CMC hydrogel group,and the epidermis of the new granulation tissue was complete and thick.Parallel mature collagen fibers were observed in the usAgNPs-PL/CMC hydrogel group.After 7 days of treatment,CD31 immunohistochemistry and Ki67 immunofluorescence staining showed that the usAgNPs-PL/CMC hydrogel group had the highest number of microvessels and fibroblasts.(3)The results showed that usAgNPs-PL/CMC hydrogel could accelerate wound healing in type 1 diabetic rats by rapidly inhibiting bacteria and promoting angiogenesis.

Effect of Pre-Storage Edible Coating on Post Harvest Quality of Guava Fruits cv. Lalit Under Ambient Condition

A significant fruit crop, the guava (Psidium guajava L.), is grown around the world in a wide range of tropical and subtropical climates. The shelf life of guavas is short, and they ripen quickly after being harvested. This limited shelf life necessitates effective management techniques to ensure a consistent market supply through post-harvest treatments to extend the storage life. In this study, we aimed to assess the impact of different treatments on the quality attributes of guava fruit cv. Lalit at 3-day intervals during storage. The experiment was carried out in the Postharvest Laboratory, Department of Horticulture, Banaras Hindu University, Varanasi. The findings from our investigation revealed that guava fruits harvested at the mature green stage and treated with Carboxy methylcellulose (CMC) and sodium alginate, maintained their desirable chemical and functional qualities for an extended period, up to 12 days of storage. Specifically, the post-harvest treatment using CMC (1.5%) proved to be exceptionally effective in reducing physiological weight loss and decay loss and retarding the increase in total carotenoids and lycopene content. Additionally, it delayed the decline in total soluble solids, ascorbic acid content, chlorophyll content, total antioxidant capacity and phenolic content throughout the storage period. Therefore, this treatment showed excellent results in extending the shelf life of guava fruits and maintaining their post-harvest quality by delaying the processes of ripening and senescence, lowering spoilage, and improving marketability and appearance.

Comparing the efficacy of sodium hyaluronate eye drops and carboxymethylcellulose eye drops in treating mild to moderate dry eye disease

Purpose: Aim of this study was to compare the efficacy of sodium hyaluronate (SH) and carboxymethyl cellulose (CMC) eye drops in treating mild to moderate dry eye disease in terms of relief of symptoms, mean change in tear film breakup time, Schirmer’s test, and impression cytology of conjunctiva from baseline. Methods: An observational study was carried out during a 2?year period in our tertiary referral hospital. The study consisted of 60 patients randomly allotted to two groups to receive SH and CMC eye drops for an 8?week period. Ocular surface disease index, tear film breakup time, and Schirmer’s test were performed at baseline visit and 4 and 8 weeks of treatment, and impression cytology of conjunctiva was performed at baseline and 8 weeks. Results: Significant improvement in patient symptoms, tear film breakup time, and Schirmer’s test from baseline was seen in both SH and CMC groups at 8 weeks posttreatment, whereas impression cytology of conjunctiva in both groups did not show significant improvement at 8 weeks of treatment. Data analysis using unpaired t?test showed comparable results. Conclusion: Both CMC and SH demonstrated equal efficacy in treating mild to moderate dry eye disease.

ISOLATION AND CHARACTERIZATION OF CELLULOSE-DEGRADING BACTERIA FROM DECOMPOSING PLANT MATTER

Objective: The green plant waste consists of a high amount of lignocellulosic materials offering an intense environment for the growth of cellulolytic bacteria, which have ability to degrade plant biomass as a carbon source. This cellulase produced can be used to break down plant waste into valuable products such as monomeric sugars, biofuels, compost etc. Therefore, the aim of present study was to isolate and identify potent cellulose-degrading bacteria from decomposing plant matter and assessment of their cellulolytic activity.Methods: The cellulolytic bacteria were isolated by serial dilution technique on CMC agar media and six isolates were selected based on their cellulose hydrolysing ability. Based on the biochemical tests such as Oxidase test, Voges-Proskauer test, Methyl red test, Catalase test and sequence analysis of 16s rRNA genes.Results: The isolates were identified as Paenibacillus alvei, Paenibacillus lentimorbus, Bacillus subtilis, Bacillus nakamurai with percentage identity of 93.77%, 92.80%, 97.71% and 91.94%, respectively, as obtained from NCBI BLAST. Among these Paenibacillus alvei showed the highest cellulase activity.Conclusion: The findings of this study could pave the way for the use of cellulose as an inexpensive energy source for bacteria that are capable of producing valuable products.

Development of an improved virus plaque assay based on avicel / 生物工程学报

Avicel is made of a mixture of microcrystalline cellulose (MCC) and carboxymethyl cellulose (CMC), and used for virus plaque assay. The avicel in common use is produced by FMC Biopolymer. Due to the relatively fixed proportion of MCC and CMC, avicel in common use is not suitable for plaque determination experiment of all types of viruses. In this study, we evaluated the effect of avicel made of different proportions of MCC and CMC on virus plaque assay, and developed an improved avicel virus plaque assay featured with simple and convenient operation, good practicability and high stability. To generate avicel overlays with different proportions of MCC and CMC, twelve different 2×avicel solutions were prepared. Their overall viscosity and bottom viscosity were measured to evaluate the ease of operation. The results showed that most of the 2×avicel solutions (except the 4.8% MCC+1.4% CMC and 4.8% MCC+1.0% CMC group) were easy to absorb and prepare nutrient overlap than 2×CMC solution. In order to find the best scheme to detect the titer of porcine epidemic diarrhea virus (PEDV), these avicel overlay solutions with different proportion of MCC and CMC were used as a replacement in the standard plaque assay. By comparing the size, clarity, stability and titer accuracy of virus plaque, we identified that 0.6% MCC and 0.7% CMC was the most preferable composition of avicel overlay for PEDV plaque assay. In conclusion, we developed an improved virus plaque assay based on avicel, which may facilitate the research of virus etiology, antiviral drugs and vaccines.

Novel compound FLZ alleviates rotenone-induced PD mouse model by suppressing TLR4/MyD88/NF-

Parkinson's disease (PD) is the second most common neurodegenerative disease, but none of the current treatments for PD can halt the progress of the disease due to the limited understanding of the pathogenesis. In PD development, the communication between the brain and the gastrointestinal system influenced by gut microbiota is known as microbiota-gut-brain axis. However, the explicit mechanisms of microbiota dysbiosis in PD development have not been well elucidated yet. FLZ, a novel squamosamide derivative, has been proved to be effective in many PD models and is undergoing the phase I clinical trial to treat PD in China. Moreover, our previous pharmacokinetic study revealed that gut microbiota could regulate the absorption of FLZ

Response surface methodology-artificial neural network based optimization and strain improvement of cellulase production by Streptomyces sp / Metodologia de superfície de resposta - otimização baseada em redes neurais artificiais e melhoria de estirpes na produção de celulases por Streptomyces sp

Thirty-seven different colonies were isolated from decomposing logs of textile industries. From among these, a thermotolerant, gram-positive, filamentous soil bacteria Streptomyces durhamensis vs15 was selected and screened for cellulase production. The strain showed clear zone formation on the CMC agar plate after Gram's iodine staining. Streptomyces durhamensis vs15 was further confirmed for cellulase production by estimating the reducing sugars through the dinitrosalicylic acid (DNS) method. The activity was enhanced by sequential mutagenesis using three mutagens of ultraviolet irradiation (UV), N methyl-N'-nitro-N-nitrosoguanidine (NTG), and Ethyl methanesulfonate (EMS). After mutagenesis, the cellulase activity of GC23 (mutant) was improved to 1.86-fold compared to the wild strain (vs15). Optimal conditions for the production of cellulase by the GC 23 strain were evaluated using Response Surface Methodology (RSM) and Artificial Neural Network (ANN). The effects of pH, temperature, duration of incubation, and substrate concentration on cellulase production were evaluated. Optimal conditions for the production of cellulase enzyme using Carboxymethyl cellulose as a substrate are 55 ºC of temperature, pH of 5.0, and incubation for 40 h. The cellulase activity of the mutant Streptomyces durhamensis GC23 was further optimized to 2-fold of the activity of the wild type by RSM and ANN

Trinta e sete colônias diferentes foram isoladas de toras em decomposição das indústrias têxteis. Dentre estes, uma bactéria do solo filamentosa termotolerante, Gram-positiva, Streptomyces durhamensis vs15, foi selecionada e rastreada quanto à produção de celulase. A cepa mostrou uma formação de zona clara na placa de ágar CMC após a coloração com iodo Gram. Streptomyces durhamensis vs15 foi ainda confirmado para a produção de celulase, estimando os açúcares redutores pelo método do ácido dinitrosalicílico (DNS). A atividade foi aprimorada por mutagênese sequencial usando três mutagênicos de irradiação ultravioleta (UV), N metil-N'-nitro-N-nitrosoguanidina (NTG) e metanossulfonato de etil (EMS). Após a mutagênese, a atividade celulase do GC23 (mutante) foi melhorada para 1,86 vezes em comparação com a cepa selvagem (vs15). As condições ideais para a produção de celulase pela cepa GC 23 foram avaliadas usando a Metodologia de Superfície de Resposta (RSM) e a Rede Neural Artificial (RNA). Os efeitos do pH, temperatura, duração da incubação e concentração de substrato na produção de celulase foram avaliados. As condições ideais para a produção da enzima celulase usando Carboximetilcelulose como substrato são 55 ° C de temperatura, pH de 5,0 e incubação por 40 h. A atividade da celulase do mutante Streptomyces durhamensis GC23 foi ainda otimizada para 2 vezes a atividade do tipo selvagem por RSM e RNA.

Isolation and molecular identification of a cellulotic bacterium from muncipal waste and investigation of its cellulase production / Isolamento e identificação molecular de uma bactéria celulolítica do lixo municipal e investigação de sua produção de celulase

Municipal waste is rich in lignocellulosic compounds which contain cellulose, lignin and hemicellulose. Microorganisms can break down such compounds and convert them into glucose and other carbohydrates. The current study was performed to isolate and identify cellulolytic bacteria in municipal waste. Municipal waste samples were collected and plated on Carboxymethyl cellulose (CMC) agar. Preliminary identification of the isolates was performed using standard biochemical assays. The activity of carboxymethyl cellulose (CMCase) was specified through measuring the release of reducing sugars from CMC. Different nitrogen sources at various concentrations and initial pH values were evaluated for their effect on enzyme production. Further the enzyme production was determined at different fermentation times. Molecular identification was then performed using bacterial 16s rRNA gene amplification and sequencing. A cellulolytic bacterium was isolated from municipal waste samples and identified based on morphological, physiological and biochemical characteristics along with 16S rRNA analysis. The isolated bacterium was identified as Bacillus subtilis (accession number: KU681044). Whose growth characteristics showed that its growth curve entered the logarithmic phase following 10­18 h with the stable growth phase ranging from 23 to 37 h. The optimal carbon source for fermentation was 1% rice hull, with the nitrogen source comprised of 2% peptone and yeast extract. The the minimum CMCase activity was observed at an initial medium pH of 4.0, while the maximum was observed at pH 7. The strain grew vigorously and the cellulase yield was high at 6­24 h fermentation time period. The isolated bacteria showed the degrading potential of cellulose which could be employed in local industrial process.

Resíduos urbanos são ricos em compostos lignocelulósicos que contêm celulose, lignina e hemicelulose. Microrganismos podem quebrar esses compostos e convertê-los em glicose e outros carboidratos. O presente estudo foi realizado para isolar e identificar bactérias celulolíticas em resíduos urbanos. Amostras de resíduos municipais foram coletadas e plaqueadas em ágar Carboximetilcelulose (CMC). A identificação preliminar dos isolados foi realizada utilizando ensaios bioquímicos padrão. A atividade da carboximetilcelulose (CMCase) foi especificada através da medição da liberação de açúcares redutores da CMC. Diferentes fontes de nitrogênio em várias concentrações e valores iniciais de pH foram avaliados quanto ao seu efeito na produção de enzimas. Além disso, a produção de enzima foi determinada em diferentes tempos de fermentação. A identificação molecular foi então realizada utilizando amplificação e sequenciamento do gene bacteriano 16s rRNA. Uma bactéria celulolítica foi isolada de amostras de resíduos urbanos e identificada com base em características morfológicas, fisiológicas e bioquímicas, juntamente com a análise 16S rRNA. A bactéria isolada foi identificada como Bacillus subtilis (número de acesso: KU681044). Cujas características de crescimento mostraram que sua curva de crescimento entrou na fase logarítmica após 10-18 h com a fase de crescimento estável variando de 23 a 37 h. A fonte de carbono ótima para a fermentação foi 1% de casca de arroz, com a fonte de nitrogênio composta de 2% de peptona e extrato de levedura. A atividade mínima de CMCase foi observada em um pH médio inicial de 4,0, enquanto a máxima foi observada em pH 7. A linhagem cresceu vigorosamente e o rendimento de celulase foi alto no período de 6 a 24 horas de fermentação. As bactérias isoladas mostraram o potencial de degradação da celulose que poderia ser empregada no processo industrial local.

Dentinal Tubules Occluding Effect Using Nonthermal Atmospheric Plasma

Nonthermal atmospheric plasma has been studied for its many biomedical effects, such as tooth bleaching, wound healing, and coagulation. In this study, the effects of dentinal tubules occlusion were investigated using fluoride-carboxymethyl cellulose (F-CMC) gel, nano-sized hydroxyapatite (n-HA), and nonthermal atmospheric plasma. Human dentin specimens were divided to 5 groups (group C, HA, HAF, HAP, and HAFP). Group HA was treated with n-HA, group HAF was treated with n-HA after a F-CMC gel application, group HAP was treated with n-HA after a plasma treatment and group HAFP was treated with n-HA after a plasma and F-CMC gel treatment. The occlusion of dentinal tubules was investigated using scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDS), which shows Ca/P ratio. In the EDS results, a higher Ca/P ratio was shown in the groups including n-HA than in the control group. The specimens of group HAP and HAFP had a higher Ca/P ratio in retentivity. In the SEM results, there was not a significant difference in the amount of times applied. Therefore, this study suggests F-CMC gel and n-HA treatment using nonthermal atmospheric plasma will be a new treatment method for decreasing hypersensitivity.

Escherichia coli expressing endoglucanase gene from Thai higher termite bacteria for enzymatic and microbial hydrolysis of cellulosic materials

Background: Endoglucanase plays a major role in initiating cellulose hydrolysis. Various wild-type strains were searched to produce this enzyme, but mostly low extracellular enzyme activities were obtained. To improve extracellular enzyme production for potential industrial applications, the endoglucanase gene of Bacillus subtilis M015, isolated from Thai higher termite, was expressed in a periplasmic-leaky Escherichia coli. Then, the crude recombinant endoglucanase (EglS) along with a commercial cellulase (Cel) was used for hydrolyzing celluloses and microbial hydrolysis using whole bacterial cells. Results: E. coli Glu5 expressing endoglucanase at high levels was successfully constructed. It produced EglS (55 kDa) with extracellular activity of 18.56 U/mg total protein at optimal hydrolytic conditions (pH 4.8 and 50°C). EglS was highly stable (over 80% activity retained) at 40­50°C after 100 h. The addition of EglS significantly improved the initial sugar production rates of Cel on the hydrolysis of carboxymethyl cellulose (CMC), microcrystalline cellulose, and corncob about 5.2-, 1.7-, and 4.0-folds, respectively, compared to those with Cel alone. E. coli Glu5 could secrete EglS with high activity in the presence of glucose (1% w/v) and Tween 80 (5% w/v) with low glucose consumption. Microbial hydrolysis of CMC using E. coli Glu5 yielded 26 mg reducing sugar/g CMC at pH 7.0 and 37°C after 48 h. Conclusions: The recombinant endoglucanase activity improved by 17 times compared with that of the native strain and could greatly enhance the enzymatic hydrolysis of all studied celluloses when combined with a commercial cellulase.

Evaluation of the Antimicrobial Effect of Carboxymethyl Cellulose versus Silver with Saline Dressing in Diabetic Ulcers.

Background: The diabetic foot ulcer is a major complication of diabetes mellitus. (1) It occurs in 15% of all patients with diabetes and precedes 84% of all lower leg amputations. (2) Diabetes mellitus impedes wound healing by prolonging the inflammatory phase. Increased glucose in the tissue precipitates infection. (3) Diabetic microangiopathy which affects microcirculation. Increased glycosylated hemoglobin decreases the oxygen dissociation. Increased glycosylated tissue protein decreases the oxygen utilization. This study is intended to show the efficacy of carboxymethyl cellulose (CMC) dressing for a faster healing of diabetic ulcers when compared with the conventional saline dressing. Materials and Methods: This study was a prospective case–control comparative study conducted at the Department of General Surgery and Gastroenterology, father Muller Medical College, Mangalore, from August to July 2016. 80 consenting patients who met the predefined criteria were taken for the study and divided into two groups, 40 patients each is put in the CMC with silver dressing group and the conventional saline dressing group. Results: There was no statistically significant difference between the two groups in terms of gender, age, glycemic control, and site of ulcer P < 0.001. In our study, we found that there was statistically significant difference in the rate of infection between the two groups. Conclusion: Silver impregnate dressings have a role in the management of diabetic ulcers by reducing the local burden of infection which is an important cause for non-healing ulcer analgesia.

Effect of combined sodium hyaluronate and carboxymethyl cellulose on ocular surface in rat dry eye model

This study was conducted to evaluate three different mixed formulations of sodium hyaluronate (SH) and carboxymethyl cellulose (CMC) using a low-humidity air flow-induced rat dry eye model and determine the most suitable mixture. The total thickness of the cornea, corneal epithelial thickness, corneal stroma thickness, damaged corneal epithelium percentage region, thickness of the bulbar conjunctiva epithelium, number of goblet cells, goblet cell occupation percentage region, and damaged bulbar conjunctiva epithelium percentage region were measured by histomorphological evaluation. After 5 h exposure to drying airflow, the thickness of the cornea and conjunctiva was decreased with desquamation of the corneal and conjunctiva epithelium. However, these dry eye symptoms were markedly inhibited by treatment with the reference and test formulations. More favorable effects on decreased thickness were detected in response to the CMC than the SH. However, SH had a greater protective effect against corneal and conjunctiva epithelial damage. The application of a mixture of 0.1% SH and 0.2% CMC showed more favorable effects on the corneal and conjunctival damage and the stabilization of the ocular surface than SH or CMC alone.

Formulation and evaluation of simvastatin buccal film.

The aim of this work was to develop and evaluate a buccal film for delivery of simvastatin. Buccal films containing carboxymethyl cellulose (CMC) with and without Polyvinylpyrrolidone (PVP) as polymers were prepared. Tween 80 was included with and without propylene glycol (PG) to modulate the characteristics of the films. The films were prepared by solvent casting with drug concentration being maintained at 2.5 mg/cm2. In absence of Tween and PG, the films were opaque due to precipitation of drug. PG reduced the swelling index and increased the thickness of the film due to shrinkage. Incorporation of PVP into the films increased the bioadhesion force and time. The rate of drug release depended on the composition of the film with the presence of PVP increasing the release efficiency compared to the corresponding PVP free films. Similarly, incorporation of PG increased the drug release efficiency. Thermal analysis indicated the presence of the drug in amorphous form or as a solid solution in the film components. The developed films are promising for buccal administration of simvastatin.

Dexamethasone and sodium carboxymethyl cellulose prevent postoperative intraperitoneal adhesions in rats

We aimed to evaluate the effects of the barrier agent sodium carboxymethyl cellulose (SCMC) with and without dexamethasone for the prevention of postoperative adhesion formation in a rat model of postoperative peritoneal adhesion. A total of 160 three-month old male and female Wistar rats underwent a laparotomy, and adhesions were induced by ileocecal abrasion. Rats were randomly assigned to 4 groups (n=40 each): group A, untreated; group B, treated with SCMC only; group C1, treated with SCMC + 3 mg dexamethasone, and group C2, treated with SCMC + 8 mg dexamethasone. After 12 days, adhesion formation and histopathological changes were compared. In groups A, B, C1, and C2, the mortality rates were 10, 5, 5, and 5%, respectively. In groups C1 and C2, the adhesions were filmy and easy to dissect and were milder compared with those in groups A and B. The total adhesion score in group C1 (3.38±0.49) was significantly lower than that of group B (6.01±0.57; P<0.01) or group A (8.01±0.67; P<0.05). There was no significant difference in adhesion formation between groups C1 and C2. Compared with groups A and B, groups C1 and C2 exhibited milder histopathological changes. SCMC in combination with dexamethasone can prevent adhesion formation and is a better barrier agent than SCMC alone. The safety and feasibility of SCMC in combination with dexamethasone to prevent adhesion formation after abdominal surgery warrants further clinical study.

Isolation and identification of a cellulolytic bacterium from the Tibetan pig's intestine and investigation of its cellulase production

Background The Tibetan pig is a pig breed with excellent grazing characteristics indigenous to the Qinghai-Tibet plateau in China. Under conditions of barn feeding, 90% of its diet consists of forage grass, which helps meet its nutritional needs. The present study aimed to isolate and identify a cellulolytic bacterium from the Tibetan pig's intestine and investigate cellulase production by this bacterium. The study purpose is to provide a basic theory for the research and development of herbivore characteristics and to identify a source of probiotics from the Tibetan pig. Results A cellulolytic bacterium was isolated from a Tibetan pig's intestine and identified based on morphological, physiological, and biochemical characteristics as well as 16S rRNA analysis; it was designated Bacillus subtilis BY-2. Examination of its growth characteristics showed that its growth curve entered the logarithmic phase after 8-12 h and the stable growth phase being between 20 and 40 h. The best carbon source for fermentation was 1% corn flour, while 2% peptone and yeast powder compound were the best nitrogen sources. The initial pH during fermentation was 5.5, with 4% inoculum, resulting in a high and stable amount of enzyme in 24-48 h. Conclusions The isolated BY-2 strain rapidly grew and produced cellulase. We believe that BY-2 cellulase can help overcome the shortage of endogenous animal cellulase, improve the utilization rate of roughage, and provide strain sources for research on porcine probiotics.

Preparation, Characterization and In-vitro Evaluation of Microcapsules for Controlled Release of Diltiazem Hydrochloride by Ionotropic Gelation Technique.

The problems of frequent administration and variable low bioavailability after oral administration of conventional dosage forms of diltiazem can be attenuated by designing it in the form of microcapsules which would facilitate intimate contact with the absorption surface and thereby improve and enhance the bioavailability. Diltiazem-loaded microcapsules were successfully prepared by ionotropic gelation technique employing Sodium carboxy methylcellulose, Xanthan gum as rate controlling polymers and Aluminium chloride as cross linking agent. Microcapsules obtained were discrete, spherical, free flowing and showed a maximum encapsulation efficiency of 91.20 ± 0.08%. Particle size of the microcapsules was found to be in the range of 1009 – 1311 μm. Interaction studies performed using FTIR spectroscopy revealed that there were no drug and polymer interactions. The drug remained dispersed in the polymer matrix in amorphous state, which was confirmed by X-ray diffraction analysis. The in vitro drug release follows matrix-diffusion controlled release and the release mechanism was non-Fickian type controlled by swelling and relaxation of polymer. There was no significant change in drug content and cumulative drug release of drug-loaded microcapsules stored at different storage condition after 90 days. From the study, it was concluded that diltiazem loaded microcapsules could be successfully prepared by ionotropic gelation technique with high entrapment efficiency and prolonged release characteristics.

Antiadhesive effect and safety of sodium hyaluronate-carboxymethyl cellulose membrane in thyroid surgery / 대한외과학회지

PURPOSE: A number of researchers have suggested the use of sodium hyaluronate carboxymethyl cellulose (HA-CMC) membrane for preventing postoperative adhesion. This study evaluated the antiadhesive effect and safety of HA-CMC membrane in thyroidectomy for papillary thyroid cancer. METHODS: One hundred sixty-two patients who underwent thyroidectomy were prospectively randomized. In the study group of 80 patients, the 7.5 cm x 13 cm HA-CMC membrane was applied to the operative field after thyroidectomy. The subjects were asked about complications including adhesive symptoms using an 8-item questionnaire at 2 weeks, 3 months, and 6 months after surgery. In addition, items on the appearance of neck wrinkles and scars were evaluated by a physician who had no information about the patient's allocation. RESULTS: There were no significant differences in complications such as swallowing difficulty, and wrinkles between study and control groups. Both groups presented significantly decreased scores over time in swallowing difficulty, and wrinkles. There were no complications regarding the HA-CMC membrane. CONCLUSION: The antiadhesive effect of HA-CMC membrane in thyroid surgery is still uncertain, although it is biologically safe. Further investigation is needed to confirm the antiadhesive effect of HA-CMC membrane in thyroid surgery.

Purification and biochemical characterization of endoglucanase from Penicillium pinophilum MS 20.

Cellulases find increasing prominence in sustainable production of fuel and feedstock from lignocellulosic biomass. The purification and biochemical characterization of individual components of cellulase complex is important to understand the mechanism of their action for the solubilization of crystalline cellulose. In this study, an extra-cellular endoglucanase isolated from culture filtrate of Penicillium pinophilum MS 20 was purified to homogeneity by ammonium sulphate precipitation, ion-exchange chromatography and gel filtration. The purified endoglucanase (specific activity 69 U/mg) was a monomeric protein with molecular mass of 42 kDa, as determined by SDS-PAGE. The endoglucanase was active over a broad range of pH (4-7) with maximum activity at pH 5 and showed optimum temperature of 50°C. It retained 100% activity at 50°C for 6 h and half- lives of 4 h and 3 h at 60°C and 70°C, respectively. The kinetic constants for the endoglucanase determined with carboxymethyl cellulose as substrate were Vmax of 72.5 U/mg and apparent Km of 4.8 mg/ml. The enzyme also showed moderate activity towards H3PO4 swollen cellulose and p-nitrophenyl β-D-glucoside, but no activity towards filter paper, Avicel and oat spelt xylan. The activity was positively modulated by 47, 32 and 25% in the presence of Co2+, Zn2+ and Mg2+, respectively to the reaction mixture. The wide pH stability (4-7) and temperature stability up to 50°C of endoglucanase makes the enzyme suitable for use in cellulose saccharification at moderate temperature and pH.

The Effect of Hyaluronate-Carboxymethyl Cellulose on Bone Graft Substitute Healing in a Rat Spinal Fusion Model

OBJECTIVE: The aim of this study was to evaluate the impact of sodium hyaluronate-sodium carboxymethyl cellulose (HA-CMC), an anti-adhesive material for spinal surgery, on bone fusion by applying it to rat spinal models after lumbar posterolateral fusion. METHODS: Lumbar posterolateral fusion was performed at L4-5 using bone graft substitutes in 30 rats. HA-CMC was injected in 15 rats at a dose of 0.2 cc (HA-CMC group) and a saline solution of 0.2 cc in the other 15 rats (control group). Simple radiographs were taken until postoperative 9 weeks with an interval of one week. At postoperative 4 and 9 weeks, three dimensional computed tomography (3D CT) scanning was performed to observe the process of bone fusion. At 9 weeks, bone fusion was confirmed by gross examination and manual palpation. RESULTS: There were no statistically significant differences in bone fusion between the two groups. 3D CT scanning did not reveal significant differences between the groups. The gross examination and manual palpation after autopsy performed at 9 weeks confirmed bone union in 93.3% of both groups. CONCLUSION: The anti-adhesive material used for spinal surgery did not have adverse effects on spinal fusion in rats.

The Effect of Hyaluronate-Carboxymethyl Cellulose on Tissue Adhesion after Achilles Tendon Tenorraphy in Rats / 대한족부족관절학회지

PURPOSE: The purpose of this study was to evaluate the effect of Sodium hyaluronate-Sodium carboxymethyl cellulose (HA-CMC) on tissue adhesion after tenorrhapy in tenotomized Achilles tendon of the Sprague-Dawley rat. MATERIALS AND METHODS:Twenty-eight legs of 14 Sprague-Dawley rat were used in study. After tenotomy of the Achilles tendons, tenorrhaphies were performed. Simple tenorrhaphy without any other procedures were performed on the left Achilles tendons (control group), and additional HA-CMC injections were done prior to the tenorrhaphy on the right Achilles tendons (HA-CMC group). Gross and histological examinations were made to identify differences between the two groups, 1, 2, 6, 8, 10, 12 and 14 weeks respectively. RESULTS:Distinct decrease in granulation tissues and adhesions were seen in the HA-CMC group during gross inspection at 6 and 8 week after the operation. On histological analysis of the HA-CMC group, although increased infiltrations of inflammation cells were observed during 1 week, less adhesion were seen at 6, 8 and 10 weeks after the operation. In HA-CMC group, superior healing processes were seen at 6, 8 and 10 weeks and less fibrotic changes, compared to control group, were seen at 2 and 6 weeks. CONCLUSION: Prevention of adjacent tissue adhesion was made possible through decrease in collagen deposition and fibrosis by injecting HA-CMC before tenorrhaphy of Achilles tendon. Also, histologically faster healing process of the collagen fibers within the Achilles tendon was observed