methyl cellulose

The objective of this study was to determine the effect of sodium alginate and methyl cellulose coatings on the respiration rate, firmness, acidity, pH, total soluble solids and desiccation rate of peaches. Coated and uncoated control fruits were stored at 15°C and 40% RH. Respiration rate, moisture loss, and changes in firmness, total titrable acidity, pH and total soluble solids of coated and control samples were determined at 3-day intervals. The respiration rate, moisture loss and changes in quality parameters were much lower in coated peaches as compared with the control. While the maximum acceptable shelf-life at 15°C for control samples was 15 days, the coated samples maintained their acceptability up to 21 and 24 days, respectively, with sodium alginate and methyl cellulose coating. The reduced respiration and transpiration rates as a result of coatings were considered responsible for maintaining the quality and increasing the shelf-life of peaches.

Cellulose and its derivatives (methyl cellulose, sodium carboxymethyl cellulose, hydroxymethyl cellulose and hydroxypropyl ce.llulose) used as exeipients in pharmaceutical industry can be eharacterised by simultaneous thermoanalytieal (DTA and TG) methods, based on the temperatures of exothermie peaks. Lignine cellulose can be identified by taking into account the differenee ha temperature between the first exothermic DTA peak and the corresponding DTG peak.

The mechanical properties of solid foods have not been extensively studied. This is due to the fact that most foods behave as viscous fluids or viscoelastic ''solids''. In the case of freezing of foods or by considering solid foods (i.e. chocolate), food can be considered as a solid system. This paper presents results obtained with Tylose Ò (a model food made of a methyl cellulose gel-74% water content) and chocolate. The Young's modulus, the Poisson ratio, the bulk modulus and the coefficient of thermal expansions have been determined using specific procedures. These results can be of interest to model the thermomechanical behavior of foods undergoing freezing.

Edible coatings regulate water vapor, oxygen and carbon dioxide transfer in or out of the produce thereby influencing the ongoing respiratory activity and produce quality. The objective of this study was to evaluate the effect of a methyl cellulose-based coating on the respiration rate, color and texture of avocados stored at room temperature. Avocados were initially surface disinfected, washed and air-dried. They were then immersed in the coating solution for 1 min at 20 1C, air-dried for 10 min and stored at 20 1C in an open box. At 2-day intervals, fruits were removed and evaluated for respiration rate, color and texture. Respiration rate was evaluated by measuring the rate of CO 2 produced from a given quantity of fruits per unit time. Color and texture of avocados were measured using instrumental techniques. Coated avocados demonstrated lower respiration rates, greener color and higher firmness as compared with the uncoated control during the entire storage. The appearance of brown spots and mesocarp discoloration normally associated with fruit ripening were delayed in the coated fruits.

Foams were prepared from starfruit (Averrhoa carambola L.) puree by adding various concentrations of methyl cellulose (Methocel 65HG). All foams were prepared by whipping using a kitchen mixer. Overrun of foams from various concentrations of methyl cellulose were compared. Average bubble diameter and bubble size distribution were calculated based on microphotography. Overrun and stability of foams increased with increasing methyl cellulose concentration until maximum value was obtained at methyl cellulose concentration of 40 g/kg. At this concentration, the overrun value of 653.2% and foam density of 0.153 g cm−3 was obtained. Higher concentration of methyl cellulose produced larger air bubbles. The size of the air bubbles showed a wide distribution as the methyl cellulose concentration was increased, with the average diameter ranged from 176 to 381 μm.

The objective of this study was to determine the effect of sodium alginate and methyl cellulose coatings on the respiration rate, firmness, acidity, pH, total soluble solids and desiccation rate of peaches. Coated and uncoated control fruits were stored at 15°C and 40% RH. Respiration rate, moisture loss, and changes in firmness, total titrable acidity, pH and total soluble solids of coated and control samples were determined at 3-day intervals. The respiration rate, moisture loss and changes in quality parameters were much lower in coated peaches as compared with the control. While the maximum acceptable shelf-life at 15°C for control samples was 15 days, the coated samples maintained their acceptability up to 21 and 24 days, respectively, with sodium alginate and methyl cellulose coating. The reduced respiration and transpiration rates as a result of coatings were considered responsible for maintaining the quality and increasing the shelf-life of peaches.

Humidity sensitive nanostructured hybrid films were synthesized from hydroxyl propyl methyl cellulose (HPMC) and tetra ethoxy ortho silicate (TEOS) via sol–gel route by microwave assistance method. HPMC and TEOS were used as organic and inorganic precursors, respectively. FT-IR spectra of the hybrid material revealed the formation of organic–inorganic networks between HPMC and TEOS. XRD spectra and micrographs showed the formation of HPMC/TEOS amorphous nano hybrids film like structures. Surface roughness was measured using an AFM was 120 nm and measured film thicknesses were between 20 and 24 μm. Hybrid films have showed better linear sensor response, lower hysteresis (<1% RH), faster response (5 s) and recovery time (10 s), and short-term stability (30 min at least). Using Material Studio 3.2 Software, the adsorption phenomena were explained to that of humidity sensing property.

A novel green method for the synthesis of conductive nanocomposite -using silver nitrate, methyl cellulose (MC), glycerol, and aniline- was adopted. Here, silver nitrate was used as a precursor, methyl cellulose as both reducing and capping agent, glycerol as a co-reducing and ductility agent and water as solvent. While silver nitrate oxidizes aniline to polyaniline, it is reduced to silver nanoparticles. Doing so, both conductive polyaniline and conductive silver nanoparticle were in-situ synthesized via the formation of methyl cellulose- silver-polyaniline nanocomposite. Reproducibility of the nanocomposite revealed that the synthesis process is consistent. The nanocomposite film was characterized by FTIR, SEM, EDAX, XRD, and conductivity. XRD pattern showed poly crystallinity. TEM of the colloidal solution showed different particle shapes of AgNPs with size from 4-36 nm and d-spacing of 0.22 nm. SAED exhibits ring pattern with bright spots displaying polycrystallinity. Nanocomposite film, coated glass, cotton and polyester fabrics showed promising conductivity.

In this research, the effect of mucoadhesive polymers such as hydroxyl propyl methyl cellulose (HPMC) with viscosity grade 60 and 500 mPas, sodium carboxy methyl cellulose (NaCMC) and carbopol 934 (Cp 934) alone or in combination with each other on the release profile of prednisolone was studied and mucoadhesion strength of these buccoadhesive formulations was evaluated. The results showed that the release of prednisolone from HPMC with viscosity grade 60 mPas and Cp 934 alone was fast and their mucoadhesion strengths was low. On the other hand, the release rates of prednisolone from the HPMC viscosity grade 500 mPas and NaCMC and mucoadhesion strengths were moderate and suitable. The results showed that with different blends of HPMC viscosity grade 500 mPas or NaCMC and Cp 934 with increasing in HPMC or NaCMC/Cp 934 ratio a remarkable decrease in the rate of drug release and an appreciable increase in the mucoadhesion strength was observed. Except from the formulations prepared with HPMC viscosity grade 60 and 500 mPas, other formulation had more fluctuations in release profiles and their kinetics of release were not fitted to zero order model.

Methylcellulose (MC) is a thermo-reversible physical hydrogel. This study investigates the thermodynamic characteristics of gelation mechanism for MC. The relative and absolute specific heat capacity values of the hydrogel system were modeled using an empirical formulation to facilitate calculation of thermodynamic parameters. Experiments verifying the assumptions for the model formulation were conducted and are discussed. Parameters such as enthalpy, entropy, and changes in their magnitude as a function of temperature were calculated and their trends were studied. The implications of these observations on the various stages of the gel formation process and the associated mechanisms are evaluated. The studies revealed that the gelation of MC is a temperature-driven process rather than only driven by the heat input, and it attains a state of equilibrium under isothermal conditions. During gelation, the entropy of the overall (MC+water) system increases due to an increase in the disorderliness of the MC system.

The buccal mucoadhesive tablets of nifedipine were fabricated with objective of avoiding first pass metabolism and prolonging duration of action. The mucoadhesive polymers used in formulations were carbopol (cp934), hydroxyl propyl methyl cellulose (HPMC K4M), carboxy methyl cellulose (CMC), and tamarind seed polysaccharide (TSP) .These formulations were characterized for physiochemical parameters, in vitro retention time, in vitro bioadhesive strength, percent hydration and drug release. The modified in vitro assembly was used to measure the bioadhesive strength of tablets with fresh goat buccal mucosa as a model tissue. The best mucoadhesive performance and in vitro drug release profile were exhibited by the tablet containg carbopol and TSP in the ratio of 1:1. This formulation was more comfortable to the user due to less erosion, faster hydration rate, and optimum pH of surrounding medium.

Chronic myelogenous leukemia (CML) is a clonal disorder of the hematopoietic stem cell characterized by the coexistence of Philadelphia-negative (Ph-) with Ph+ progenitors. CML progenitor cells have been shown to be defective in adherence to marrow stroma. The present study investigated at the cytogenetic level marrow-derived CML clonogenic cells generated from the stroma-adherent cell fraction. On direct cytogenetic analysis, the overall mean ( f SEM) percentage of Ph-metaphases was 3% f 1 %.

Diclofenac sodium ocuserts were prepared by using different polymers such as hydroxy propyl methyl cellulose (HPMC), hydroxy propyl cellulose (HPC), methyl cellulose (MC) and ethyl cellulose (EC) at various concentrations and combinations using dibutyl phthalate (DBP) as plasticizer. The ocuserts is prepared by solvent casting technique. The prepared ocuserts were evaluated for moisture absorption, moisture loss, thickness, weight variation, folding

The conduction properties of HMC polymer gel prepared by the phase inversion method were investigated through the diffusion coefficient in order to confirm the conduction mechanism. The solution introduced in the polymer is stored in the pores and then penetrates into the polymer chains. For swelling the polymer network. A model describing the swelling hidroxy-methyl cellulose is presented. The model is used to predict the type liquid-liquid phase separation (instantaneous or delayed) that occurs when HMC-PVPD-Solvent-Water casting solutions are immersed in a gelation bath. The model includes the thermodynamic interactions parameters and the transport parameters. The predictions of the model agree with the experimental observations.

Foam expansion and foam stability of the bael (Aegle marmelos L.) fruit pulp foam was studied. Foams were prepared from various pulp concentrations (PC) by adding different concentration of glycerol monostearate (GMS) and methyl cellulose (MC) at different whipping time (WT). Response surface methodology was used to predict the foam stability and expansion. Thirty experiments were carried out using a central composite rotatable design with four independent variables (GMS, MC, PC, and WT). Second-order polynomial equations were developed after removing insignificant terms for predicting foam expansion (R 2 =0.85) and stability (R 2 =0.95). The optimum conditions achieved after the numerical and graphical optimization for maximum foam expansion and stability was: GMS (3.10 g/100 g pulp), MC (0.32 g/100 g pulp), PC (13.2°Bx), and WT (2 min). The desirability of 0.712 was achieved at this optimum point. The predicted values of foam density and foam drainage volume were 0.658 gcm −3 and 1.75 mL, respectively, at optimum parameters while the experimental values were 0.635± 0.02 gcm −3 and 1.75±0.12 mL, respectively.

We report the development of a series of physical hydrogel blends composed of hyaluronan (HA) and methyl cellulose (MC) designed for independent delivery of one or more drugs, from 1 to 28 days, for ultimate application in spinal cord injury repair strategies. To achieve a diversity of release profiles we exploit the combination of fast diffusion-controlled release of dissolved solutes from the HAMC itself and slow drug release from poly(lactide-co-glycolide) particles dispersed within the gel. Delivery from the composite hydrogels was demonstrated using the neuroprotective molecules NBQX and FGF-2, which were released for 1 and 4 days, respectively; the neuroregenerative molecules dbcAMP and EGF, and proteins α-chymotrypsin and IgG, which were released for 28 days. α-chymotrypsin and IgG were selected as model proteins for the clinically relevant neurotrophin-3 and anti-NogoA. Particle loaded hydrogels were significantly more stable than HAMC alone and drug release was longer and more linear than from particles alone. The composite hydrogels are minimally swelling and injectable through a 30 gauge/200 µm inner diameter needle at particle loads up to 15 wt.% and particle diameters up to 15 µm.

The present study was designed to further investigate the role of the epidermal growth factor receptor (EGFr) in mouse skin tumor promotion by evaluating the status of the EGFr in tumor promoter-treated mouse epidermis and in mouse skin tumors. Female SENCAR mice received three topical treatments of either the phorbol ester 1 2-O-tetradecanoylphorbol-1 3-acetate (TPA) or the nonphorbol esters okadaic acid and chrysarobin. Membrane proteins from SENCAR mouse epidermis were isolated 6 h after the last treatment, and the phosphotyrosine content of the EGFr and several potential substrates were examined by Western blot analysis. The results indicated that multiple applications of all three tumor promoters led to an increase in the phosphotyrosine content of the EGFr and also of several lower molecular weight proteins (Mr 8O,OOO85,OO0).

Control of physical and mechanical properties of biopolymer (derived from food hydrocolloid) porous solids in terms of stress strain relationship during compression, porosity and pore size would enable their use for a wider range of purposes. Different types of dried cellular biopolymer foams were produced using different food hydrocolloids such as locust bean and alginate gums, gelatin, low and high methoxy pectin, methyl cellulose and starches (corn and tapioca) at various proportions. First different types of wet hydrogels were prepared by varying gel processing methods. Then they dried using microwave energy under vacuum called vacuum microwave drying. Before performing the drying process the initial Young's modulus of the hydrogels was measured. Pore size analysis and distribution percentage were done using mercury pore size analyser after drying. Relationship between the pore size distribution after drying and the initial Young's modulus was developed. Compressive test was performed for dried porous solids and true stress strain relationship curves were developed to classify nature of dried foams obtained from various gel types. Scanning Electron Microscopic study of individual samples was performed to view the internal structure of dried porous biopolymers.

The objective of this study was to evaluate the in vitro and ex vivo percutaneous absorption of chlorpheniramine maleate (CPM) from different hydrogel formulations. Various concentrations of polymers, including hydroxypropylmethylcellulose (HPMC), sodium carboxymethylcellulose (NaCMC) and methyl cellulose (MC) were used in the hydrogel formulations. All experiments were conducted using cellulose dialysis membrane. The passive permeation of CPM was affected by the polymer concentrations. The effect of each polymer on the release rate of CPM was found to be statistically different (P B/0.05). The formulation which exhibited maximum drug release through cellulose membrane was then used with other membranes namely polyurethane membrane, rat skin and human skin. The release rate of CPM from different membranes was found to be statistically different (P B/0.05). Within the different diffusional barriers rat skin was found to be best alternative to human skin. It seems suitable the use of cellulose derivatives for topical application of CPM to obtain high therapeutic concentration at the application site. The synthetic membranes can be used to assess product performance in quality assurance but give little indication of its performance ex vivo.

Two types of composite films (MPC500SGF-MC and ANPSGF-MC) have been synthesized by a modified sol-gel method using different particle sizes of TiO2 powder. Methyl cellulose was added as a template to the sol for stress reduction which improved not only the amount of crystalline material immobilized on the support, but also the nanosize of the films calcined at 500°C. The physicochemical properties, including surface morphology, crystal size and adhesion on the glass substrate, were investigated by SEM and XRD. The photocatalytic activities of the films were compared using methyl orange (MO) as a model organic contaminant in water. The results on photocatalytic degradation of MO showed that the increase in photocatalytic activity for Aldrich TiO2 powder (ANP) calcined at 500°C, compared with that of Millenium PC500 composite film. The optimum degradation conditions of MO solution are determined. This study proves that particle size of starting TiO2 material is important for the prepa...

Microchip immobilized enzyme reactors (µIMERs) with immobilized endoglucanases were applied for the hydrolysis of methyl cellulose (MC). MCs of various molecular weights were hydrolyzed using two µIMERs containing immobilized celloendoglucanase Cel 5A from Bacillus agaradhaerens (BaCel 5A) connected in series. Hydrolysis by the µIMER could be confirmed from the average molar masses and molar mass distributions measured by size exclusion chromatography (SEC) with online multiangle light scattering and refractive index detection. Methylated cellooligosaccharides with degrees of polymerization (DP) between 1 and 6 formed during hydrolysis were analyzed by direct infusion electrospray ionization ion-trap mass spectrometry (ESI-ITMS). Mass spectra of µIMER-and batch-hydrolyzed samples were compared and no significant differences were found, indicating that µIMER hydrolysis was as efficient as conventional batch hydrolysis. A fast and automated hydrolysis with online MS detection was achieved by connecting the µIMER to high-performance liquid chromatography and ESI-ITMS. This online separation reduced the relative intensities of interfering signals and increased the signal-to-noise ratios in MS. The µIMER hydrolysates were also subjected to SEC interfaced with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. With this technique, oligomers with DP 3-30 could be detected. The hydrolysis by the µIMER was performed within 60 min, i.e. significantly faster compared with batch hydrolysis usually performed for at least 24 h. The µIMER also allowed hydrolysis after 10 days of continuous use. The method presented in this work offers new approaches for the analysis of derivatized cellulose and provides the possibility of convenient online, fast, and more versatile analysis compared with the traditional batch method. Cellulose is a naturally occurring polymer, which is used as raw material in a number of industrial applications, e.g., in the paper, paint, textile, food, and pharmaceutical industries. 1,2 It is a

Background: Slab gel heteroduplex analysis (HDA), a popular scanning method for genetic mutations, uses DNA fragments typically generated by PCR to create homo-and heteroduplex molecules with conformational differences and sequence-dependent electrophoretic profiles. Use of a universal heteroduplex generator (UHG) enhances the subtle variations caused by singlebase substitutions. Methods: The HDA-UHG slab gel format was modified for an efficient capillary-based method. The effect of staining dyes TOPRO5 and YOPRO1 on the analysis of heteroduplexes was studied, as well as ultraviolet absorbance and laser-induced fluorescence (LIF) detection methods. In addition, the entangled polymers hydroxyethyl cellulose, methyl cellulose, and linear polyacrylamide were evaluated as separation matrices. Results: This assay was able to detect the presence of Mycobacterium tuberculosis and its rifampin susceptibility directly from clinical specimens in dramatically reduced analysis time (30 min vs 2.5 h). Optimized conditions included 0.3% methyl cellulose as the separation matrix, on-line staining using 1 mol/L YOPRO1, and LIF detection for quantitative and reproducible analysis of single-base substitutions in the rifampin resistance-determining region of rpoB that give rise to the rifampin-resistant phenotype of M. tuberculosis. We generated 95% confidence limits using the wild-type sequence and used these limits to determine rifampin susceptibility in samples.

Background: Smoking is one of the most serious health care issues worldwide, as one third to one half of all people who smoke eventually use tobacco habitually. Chronic smoke exposure causes airway and lung parenchymal inflammation and the destruction of alveolar cell walls. Statins may have anti-inflammatory effects that would play a role in preventing the cellular damage associated with smoking.

A flavohaemoprotein (FHP) from Ralstonia eutropha, obtained in a pure and active form, has been entrapped in a film of methyl cellulose on the electrode surface and gives a stable and reproducible electrochemical response at pH 7.00 when subject to cyclic voltammetry using a glassy carbon electrode. To our knowledge, no previous direct electrochemistry had been achieved with a bacterial flavohaemoglobin, which possess both a FAD and a haem. A single couple is observed which is assigned to the haem moiety of the protein, since the same result is obtained with a semi-apo form of the protein deprived of FAD (semi-apo FHP). The data collected were further confirmed by potentiometry with a platinum electrode, and the homogeneous electron transfer rate estimated by double potential step chronocoulometry at a bare glassy carbon electrode in the presence of methyl viologen (MV). The presence of FAD in the holoprotein is easily confirmed by UV-Vis spectrophotometry, but its expected electron relay role remains elusive. The protein activates the reduction of dioxygen by about 400 mV, the reduction current being proportional to the concentration of dioxygen up to 10% in volume in the gas mixture.

The aim of the present study was to prepare and evaluate a novel buccal adhesive system (NBAS) containing propra-nolol hydrochloride (PH). A special punch was fabricated and used while preparing an NBAS. Solubility of PH in phosphate buffer solution (pH 6.6), partition ...

The electron-microscopic technique for immunogold labelling of thawed cryosectioned material (K.T. Tokuyasu, 1989, Histochem J 21: 163-171) has been adapted for use with isolated chloroplasts. Percollpurified pea (Pisum Sativum L. cv Feltham First) chloroplasts were fixed in a buffered glutaraldehyde solution and then infiltrated with a buffered solution of 10% polyvinylpyrrolidone in 2.07 M sucrose prior to freezing in liquid nitrogen and sectioning in an ultracryomicrotome. Sections were thawed, immunolabelled, and stained with ammonium molybdate in methyl cellulose on Formvar/carbon-coated Cu or Cu/Pd electron-microscope grids. Cryosectioning gave excellent structural preservation and retained antigenicity. The effectiveness of this technique in localizing proteins to their specific chloroplast compartment was assayed using antibodies raised against: (i) the large subunit of ribulose-l,5-bisphosphate carboxylase/oxygenase (Rubisco), a stromal protein, (ii) the chloroplast ATP synthase (CF1), a peripheral thylakoid protein, and (iii) different envelope membrane proteins. Antibodies raised against three members of the chloroplastic outer envelope protein (OEP) import machinery, a 34-kDa protein (OEP34 or IAP34), the channel-forming 75-kDa protein (OEP75 or IAP75), and the 86-kDa precursor protein receptor (OEP86 or IAP86) were tested for their localization. The previous localization of OEP86,

Inoculation of legume seed is an efficient and convenient way of introducing effective rhizobia to soil and subsequently the rhizosphere of legumes. However, its full potential is yet to be realised. Following widespread crop failures, the manufacture of high quality inoculants revolutionised legume technology in Australia in the 1960s. Many improvements to inoculants and the advent of an inoculant control service ensured that quality was optimised and maintained. Minimum standards for the number of rhizobia per seed were set after consideration of several factors including seed size and loss of viability during inoculation. Despite manufacturers' recommendations for storage and application of inoculants, there is a distinct lack of control over the inoculation process; hence the full potential of high quality products may not always be achieved. The efficacy of inoculation varies depending on several factors, all of which affect the number of viable rhizobia available for infection of legume roots. Increased numbers of viable rhizobia per seed by application of inoculant above the commercially recommended rate, results in a continued linear increase in nodulation and yield. Several studies have reported yield increases of up to 25%. However, applying higher quantities of inoculant is uneconomical and technically difficult. Alternatively, higher numbers of viable rhizobia per seed may be achieved by improving survival during seed inoculation. Despite recognition of the factors affecting survival of rhizobia on seed and a substantial demand for commercially pre-inoculated legume seed, poor survival is still a major concern. Desiccation, temperature and seed coat toxicity all influence survival of rhizobia on seed. Their adverse effects may be ameliorated by selecting tolerant rhizobial strains and legume seed cultivars with low toxicity or artificially, by the use of additives in the seed coating. The accumulation of the desiccant protectant trehalose in strains of rhizobia, may result in better survival under desiccation stress. Similarly, the accumulation of exopolysaccharide (EPS) may act as a barrier reducing excessive water loss. Polymeric adhesives such as gum arabic, methyl cellulose and polyvinyl pyrollidone (PVP) have improved survival. However, studies of additives used in inoculation have been ad hoc and little of their mode of action is understood. A better understanding of the mechanisms involved in the protection of rhizobia from adverse conditions will assist in defining the optimum conditions for seed inoculation and storage to ensure a higher quality product for farmers at the time of sowing.

Problem statement: Quercetin-a common bioflavonoid, is present in herbal preparations consumed by diabetic patients along with routine anti-diabetic agents. We recently showed that quercetin increases the bioavailability of pioglitazone in non-diabetic rats. Thus, present study investigated whether this pharmacokinetic interaction is also evident in diabetic animals, especially because diabetic subjects have altered Gastrointestinal (GI) function and CYP3A activity. Approach: The study was carried out in alloxan-induced (40 mg kg −1 , i.v.) diabetic rats. After 2 weeks of diabetes induction, rats were treated for 2 weeks with quercetin (10 mg kg −1 , p.o.) or vehicle (5% methyl cellulose, 10 mL kg −1). At the end of 4 weeks, these rats were used to investigate: (1) GI function in terms of gastric emptying and intestinal transit of semisolid barium sulphate meal; (2) CYP3A activity in liver and intestinal microsomes by erythromycin N-demethylase assay; (3) plasma levels of orally and intravenously administered pioglitazone (10 mg kg −1 , p.o.; 5 mg kg −1 , i.v.). Results: The results revealed that diabetic rats exhibited: (1) delayed gastric emptying and intestinal transit; (2) decreased CYP3A activity and (3) a significant increase in the oral and intravenous AUC 0-∞ of pioglitazone as compared to non-diabetic rats. Quercetin treatment prevented the diabetes-induced GI dysfunction, whereas diabetes-induced decrease in CYP3A activity and increased bioavailability of pioglitazone remained unaffected. Conclusion: The results suggested that quercetin attenuated GI dysfunction but did not affect the bioavailability of pioglitazone in diabetic rats contrary to the increase reported in nondiabetic rats. However, the safety of co-joint use of quercetin containing herbs and pioglitazone in clinical practice requires further pharmacokinetic substantiation.

was used for the first time as a reducing end derivatization reagent for oligosaccharides. This is an attractive reagent since it could be easily removed from the reaction mixture. Most important it also introduces a basic functional group that increased the sensitivity in both MALDI and nano-ESI. Depolymerization was made in two ways: one by the cellulose selective endoglucanase 5A from Bacillus agaradhaerens (Ba Cel5A) and the other by trifluoroacetic acid. The DMA derivatives formed both protonated and sodiated molecules in nano-ESI and MALDI. Tandem MS of protonated molecules yielded predominantly Y fragments from which the distribution of the substituents in the oligomers could be measured. Fragments obtained in tandem MS of sodiated molecules provided information regarding the positions of the substituents within the anhydroglucose units (AGUs). It was found that Ba Cel5A could cleave glucosidic bonds also if the AGU on the reducing side of the bond was fully methylated. The combination of DMA derivatization and tandem MS was demonstrated as a tool for the characterization of endoglucanase selectivity.

Graphite and nano-silicon-based negative electrodes in lithium-ion batteries with low binder content were evaluated. The effectiveness of styrene butadiene rubber (SBR) and various types of cellulose containing electrodes were compared to standard electrodes containing PVdF as binder. The cycling performance of lithium-based half cells in EC:DMC (1:1), 1 M LiPF 6 shows that styrene butadiene rubber (SBR), sodium carboxymethyl cellulose (Na-CMC), or both combined have a similar bonding ability as conventional poly(vinylidene fluoride) (PVdF). However, using Na-CMC the irreversible charge capacity in the first cycle decreased in comparison with electrodes containing PVdF binder. Nano-Si electrode containing 1% SBR/1% Na-CMC as binder show the same cycle stability as an identical electrode containing 10% PVdF binder.

We report the development of a series of physical hydrogel blends composed of hyaluronan (HA) and methyl cellulose (MC) designed for independent delivery of one or more drugs, from 1 to 28 days, for ultimate application in spinal cord injury repair strategies. To achieve a diversity of release profiles we exploit the combination of fast diffusion-controlled release of dissolved solutes from the HAMC itself and slow drug release from poly(lactide-co-glycolide) particles dispersed within the gel. Delivery from the composite hydrogels was demonstrated using the neuroprotective molecules NBQX and FGF-2, which were released for 1 and 4 days, respectively; the neuroregenerative molecules dbcAMP and EGF, and proteins α-chymotrypsin and IgG, which were released for 28 days. α-chymotrypsin and IgG were selected as model proteins for the clinically relevant neurotrophin-3 and anti-NogoA. Particle loaded hydrogels were significantly more stable than HAMC alone and drug release was longer and more linear than from particles alone. The composite hydrogels are minimally swelling and injectable through a 30 gauge/200 µm inner diameter needle at particle loads up to 15 wt.% and particle diameters up to 15 µm.

Vascular endothelial growth factor (VEGF) is a potent angiogenic peptide with biologic effects that include regulation of hematopoietic stem cell development, extracellular matrix remodeling, and inflammatory cytokine generation. To delineate the potential role of VEGF in patients with myelodysplastic syndrome (MDS), VEGF protein and receptor expression and its functional significance in MDS bone marrow (BM) were evaluated. In BM clot sections from normal donors, low-intensity cytoplasmic VEGF expression was detected infrequently in isolated myeloid elements. However, monocytoid precursors in chronic myelomonocytic leukemia (CMML) expressed VEGF in an intense cytoplasmic pattern with membranous co-expression of the Flt-1 or KDR receptors, or both. In situ hybridization confirmed the presence of VEGF mRNA in the neoplastic monocytes. In acute myelogenous leukemia (AML) and other MDS subtypes, intense co-expression of VEGF and one or both receptors was detected in myeloblasts and imma...

This paper investigates the adsorption of different sized carboxyl methyl cellulose (CMC) onto talc particles (adsorption isotherm, adsorption reversibility), its consequences on the particles properties (electrophoretic mobility and surface wetting) and its effect on their dispersion (settling coefficient). Throughout the paper, the properties of talc particles dispersed in CMC solution are compared to CMC pre-coated talc particles: talc particles dried in a solution of CMC before their redispersion. The adsorption of CMC onto talc was quantified at around 0.4 mg of CMC per m 2 of talc and was seen to be irreversible on washing the talc particles with distilled water. When characterising talc surface properties, it was found that CMC adsorption leads to an increase of the negative surface charge and to an increase of the wettability. The settling velocity of CMC pre-coated talc particles in water can be around 50 % lower than that of the initial talc particles. The pre-coating of talc particles by CMC is then assumed to increase their stabilization : particle aggregation is hindered by adsorbed CMC layer inducing electrosteric repulsion between the talc particles. The technique of talc pre-coating with CMC makes the talc dispersion easier and could open interesting perspectives in engineering processes using talc dispersions.

We present a very simple and effective way for the synthesis of tunable coloured silver sols having different morphologies. The procedure is based on the seed-mediated growth approach where methyl cellulose (MC) has been used as soft-template in the growth solution. Nanostructures of varying morphologies as well as colour of the silver sols are controlled by altering the concentration of citrate in the growth solution. Similar to the polymers in the solution, citrate ions also dynamically adsorbed on the growing silver nanoparticles and promote one (1-D) and two-dimensional (2-D) growth of nanoparticles. Silver nanostructures are characterized using UV–vis and HR-TEM spectroscopic study. Simulation of the UV–vis extinction spectra of our synthesized silver nanostructures has been carried out using discrete dipole approximation (DDA) method.

At the Leibniz radiocarbon lab, art and archaeological objects, often chemically conserved and thus potentially contaminated with respect to their 14 C content, are treated using a computer-controlled "Soxhlet"-type series extractor. This device uses a continuous procedure of boiling and condensation of different solvents for extraction and vacuum filtration under constant process conditions. An elutrope sequence of five solvents that dissolve most customary conservation chemicals was selected. A study of these different contaminants applied to reference wood samples with subsequent accelerator mass spectrometry (AMS) measurements demonstrates that their effective removal is dependent on the use of adequate solvents. For many contaminants (e.g. wood glue, methyl cellulose, Klucel ® , sugar, and polyethylene glycol), routine acid-alkaliacid (AAA) treatment already yields satisfactory results, whereas for Caparol ® and beeswax a relatively "mild" treatment with acetone, methanol, water, and subsequent standard AAA extraction is sufficient. Complete removal of rubber glue, epoxy resin, and paraffin can only be accomplished with our full set of solvents. The latter procedure is also appropriate when no or only incomplete information about the type of conservation material is available. For epoxy resin the contamination appears to be enriched in the alkali residue, and the easily soluble "humic acid" fraction, even after standard AAA treatment, gives satisfactory results. Two case studies on the application of the extraction procedures are presented.

Kinetics of the decay of methyl cellulosemanganate(VI) intermediate polysaccharide [MC-MnO 4 22 ] have been followed spectrophotometrically in different strong basic solutions at different temperatures, as well as, in the presence of different concentrations of perchlorate salt. The reaction is base-catalyzed. Salt never affects the reactivity. The activation parameters have been evaluated and discussed in connection with the proposal mechanism.

The effects of the peroxisome proliferators di-isononyl phthalate (DINP) and di-2-ethylhexyl phthalate (DEHP) were evaluated in young adult male cynomolgus monkeys after 14 days of treatment, with emphasis on detecting hepatic and other effects seen in rats and mice after treatment with high doses of phthalates. Groups of 4 monkeys received DINP (500 mg/kg/day), DEHP (500 mg/kg/day), or vehicle (0.5% methyl cellulose, 10 ml/kg) by intragastric intubation for 14 consecutive days. Clofibrate (250 mg/kg/day), a hypolipidemic drug used for cholesterol reduction in human patients was used as a reference substance. None of the test substances had any effect on body weight or liver weights. Histopathological examination of tissues from these animals revealed no distinctive treatment-related effects in the liver, kidney, or testes. There were also no changes in any of the hepatic markers for peroxisomal proliferation, including peroxisomal beta-oxidation (PBOX) or replicative DNA synthesis....

Edible coatings regulate water vapor, oxygen and carbon dioxide transfer in or out of the produce thereby influencing the ongoing respiratory activity and produce quality. The objective of this study was to evaluate the effect of a methyl cellulose-based coating on the respiration rate, color and texture of avocados stored at room temperature. Avocados were initially surface disinfected, washed and air-dried. They were then immersed in the coating solution for 1 min at 20 1C, air-dried for 10 min and stored at 20 1C in an open box. At 2-day intervals, fruits were removed and evaluated for respiration rate, color and texture. Respiration rate was evaluated by measuring the rate of CO 2 produced from a given quantity of fruits per unit time. Color and texture of avocados were measured using instrumental techniques. Coated avocados demonstrated lower respiration rates, greener color and higher firmness as compared with the uncoated control during the entire storage. The appearance of brown spots and mesocarp discoloration normally associated with fruit ripening were delayed in the coated fruits.

Graphite and nano-silicon-based negative electrodes in lithium-ion batteries with low binder content were evaluated. The effectiveness of styrene butadiene rubber (SBR) and various types of cellulose containing electrodes were compared to standard electrodes containing PVdF as binder. The cycling performance of lithium-based half cells in EC:DMC (1:1), 1 M LiPF 6 shows that styrene butadiene rubber (SBR), sodium carboxymethyl cellulose (Na-CMC), or both combined have a similar bonding ability as conventional poly(vinylidene fluoride) (PVdF). However, using Na-CMC the irreversible charge capacity in the first cycle decreased in comparison with electrodes containing PVdF binder. Nano-Si electrode containing 1% SBR/1% Na-CMC as binder show the same cycle stability as an identical electrode containing 10% PVdF binder.

The apoptotic response to DNA damage appears to be an innate biological mechanism for protection against tumourigenesis. It is possible that agents that protect against colorectal cancer act by enhancing the apoptotic deletion of cells suffering DNA damage, with consequent removal of those with tumourigenic mutations. We examined the acute apoptotic response to genotoxic carcinogens ('AARGC') in colonic epithelium and the possibility that dietary fibres of different fermentability might regulate AARGC. To fully define the time-course and nature of AARGC in response to the carcinogen azoxymethane (AOM), a single injection of AOM (10 mg/kg) was given to rats and apoptosis monitored in the colon by light microscopy and terminal deoxynucleotidyl transferasemediated dUTP-biotin nick end labelling staining over a 72 h period. Having defined the site and time of maximum response, two groups of eight rats were fed diets containing 10% wheat bran fibre (WB; fermentable) or 10% methylcellulose (MC; poorly fermentable) for 4 weeks. Colonic AARGC was compared by light microscopy; lumenal short chain fatty acids (SCFAs) and pH were measured as indicators of the fermentative environment. AOM-induced AARGC was maximal at 8 h and greater in distal compared with proximal colon. Apoptotic cells were situated predominantly in the lower half of the crypt, with the median at position 9 indicating involvement of daughter as well as stem cells. There was no 'second wave' of apoptosis within 72 h as follows irradiation in small intestine. Distal colonic AARGC in rats fed WB was twice that in rats fed MC (P < 0.01). Compared with MC, WB significantly lowered lumenal pH and increased all SCFAs including butyrate, while proliferation did not differ between the fibres. Certainly, dietary fibres can regulate AARGC and further studies are warranted to determine if this biological effect is the way in which dietary factors regulate tumourigenesis. Lumenal generation of butyrate may enhance AARGC as butyrate is proapoptotic in vitro.

The formation of a biphasic system from aqueous solutions of methyl cellulose induced by temperature was studied through heating curves of the polymer solution measured by absorbance spectroscopy, differential scanning calorimetry and solution viscosimetry. The treatment of the heating curve data according to a reversible two-state transition model allows us to calculate the middle point temperature (T m) of the formation of the two phases and the thermodynamic functions associated to the polymer aggregation. The middle point temperature was found within the range 50-70°C. It decreased significantly in a Na 2 SO 4 0.3 M medium when the polymer concentration increased. The heat associated to the two-phase formation was positive and it increased with increases in temperature. Cosolutes that affect the water structure induced changes in the T m values, which suggests the presence of a hydrophobic effect in the two-phase formation from the polymer solution. Hydrophilic proteins were partitioned in favour of the methyl cellulose rich phase according to their surface hydrophobicity. The partition was also influenced by the presence of salts that modify the protein hydrophobicity such as sodium sulphate.

In this research, the effect of mucoadhesive polymers such as hydroxyl propyl methyl cellulose (HPMC) with viscosity grade 60 and 500 mPas, sodium carboxy methyl cellulose (NaCMC) and carbopol 934 (Cp 934) alone or in combination with each other on the release profile of prednisolone was studied and mucoadhesion strength of these buccoadhesive formulations was evaluated. The results showed that the release of prednisolone from HPMC with viscosity grade 60 mPas and Cp 934 alone was fast and their mucoadhesion strengths was low. On the other hand, the release rates of prednisolone from the HPMC viscosity grade 500 mPas and NaCMC and mucoadhesion strengths were moderate and suitable. The results showed that with different blends of HPMC viscosity grade 500 mPas or NaCMC and Cp 934 with increasing in HPMC or NaCMC/Cp 934 ratio a remarkable decrease in the rate of drug release and an appreciable increase in the mucoadhesion strength was observed. Except from the formulations prepared with HPMC viscosity grade 60 and 500 mPas, other formulation had more fluctuations in release profiles and their kinetics of release were not fitted to zero order model.

The procedures involving the growth of cell colonies in semi-solid media, such as methyl cellulose or agar, provide a score of colony-forming-units (CFUs) by means of morphology, and allow the application of cytochemistry. However, a better characterization of the growing cells by employing monoclonal antibodies is impaired by the medium itself. Plasma clot is a possible alternative, allowing immunofluorescence as well as immunoenzymatic techniques. We have developed a staining procedure which can be performed using both peroxidase-or alkaline phosphatase-conjugated reagents; the colonies, growing in plasma clot, can be stained in situ, without transferring the cells. In this paper we report on the study of six different cell lines stained by immunocytochemical techniques with appropriate monoclonal antibodies.

At ITN, PM10 and PM2.5 aerosols were collected on Nuclepore polycarbonate filters of 47 mm diameter, using Gent samplers at 15-17 l/min air flux. Filters were analyzed by INAA and PIXE. The availability of certified filters was very scarce, viz.: (1) fly ash embedded in a methyl cellulose 47 mm foil 10 µm thick, BCR CRM128, (2) particle-size reduced air particulate matter (APM) to simulate PM2.5 aerosol matter deposited on a 47 mm polycarbonate filter membrane, NIST SRM 2783. The high price and scarcity of APM standards did not permit their frequent use for analytical quality control. At ITN, to control the filter results' accuracy, the chemical elements potassium, iron and zinc, determined by both techniques, were systematically compared. After a few improvements introduced in INAA, this technique was now considered at ITN as the reference technique in air particulate measurements. Comparison of INAA to PIXE was discussed. Compared to previously reported situation it was concluded that the results were in better agreement for iron and zinc, and potassium values were still biased to the same extent as before.

The supercritical antisolvent (SAS) technique was used to prepare ethyl cellulose/methyl cellulose blends, two biocompatible polymers commonly used as drug carriers in controlled delivery systems. Ethyl cellulose is widely used as a drug carrier. The drug release of the delivery devices can be controlled to some extent by addition of a water-soluble or water swellable polymer, such as methyl cellulose. This leads to the solubility enhancement of poorly water-soluble molecules. SAS experiments were carried out at different operational conditions and microspheres with mean diameters ranging from 5 to 30 m were obtained. The effect of CO 2 and liquid flow, temperature and pressure on particle size and particle size distribution was evaluated. The microspheres were precipitated from a mixture of dichloromethane (DCM) and dimethylsulfoxide (DMSO) (4:1 ratio). The best process conditions for this mixture were according to our study 40 • C and 80 bar.

The diffusion kinetics and factors affecting the migration of vanillin from chitosan/methyl cellulose (Chi/MC) films into water, cantaloupe juice (CJ), pineapple juice (PJ), and citrate buffer adjusted to pH values of 3.5, 5, and 6.5 were studied. Vanillin was incorporated into the Chi/MC films to provide an inhibitory effect against microorganisms. Initial vanillin concentration in the films, temperature, and pH of extracting solvent impacted the migration behavior of vanillin. The diffusion coefficients (D) followed the Arrhenius equation and increased as temperature increased for all the solvents. As temperature rose, the rate increment of the diffusion of vanillin into pineapple juice was higher than that into water and cantaloupe juice. Films containing lower vanillin content had a higher diffusion coefficient than those containing high vanillin content. Migration of vanillin was affected by pH rather than acid concentration. Lower pH resulted in a higher migration rate.

: The buccal mucoadhesive tablets of nifedipine were fabricated with objective of avoiding first pass metabolism and prolonging duration of action. The mucoadhesive polymers used in formulations were carbopol (cp934), hydroxyl propyl methyl cellulose (HPMC ...