JBiopest 7(2):110-123(2014) Management of early blight of tomato JBiopest 5(1): 1-6 ©449 Cinnamomum zeylanicum extracts and their formulations control early blight of tomato

ABSTRACT Alternaria solani causes early blight in plants belonging to family Solanaceae

Synthesis and characterization of polystyrene-blockpoly(vinylbenzoic acid): a promising compound for manipulating photoresponsive properties at the nanoscale

"Published online: 27 January 2015"Using reversible addition-fragmentation chain transfer (RAFT) polymerization, the effect of PSt macroRAFT and 4VBA ratio on the synthesis of a carboxylic acid functional block copolymer (PSt-b-P4VBA) was studied. PSt macroRAFT polymer was initially prepared followed by the insertion of 4-vinylbenzoic acid (4VBA) monomer. The chemical structure of the diblock copolymer was confirmed by NMR and FTIR. The effect of PSt macroRAFT and 4VBA ratio on copolymerization yield and on molecular weight distribution was assessed by gel permeation chromatography. The rate of polymerization did not change as the 4VBA/PSt macroRAFT ratio increased, indicating an ideal amount of 4VBA insertion. An optimal ratio of [PSt macroRAFT]:[AIBN]:[4VBA] was 1.2:1:180. DSC and XRD confirmed the amorphous structure of homo and copolymer. Thermal stability was higher for PSt-b-P4VBA forming activated porous carbon char by dehydration, carbonization and oxidation. SEM and STEM observations showed a morphological evolution between PSt macroRAFT and the correspondent copolymer.The authors acknowledge the n-STeP-Nanostructured systems for Tailored Performance, with reference NORTE-07-0124-FEDER-000039, supported by the Programa Operacional Regional do Norte (ON.2), PEst-C/CTM/LA0025/2013 (Strategic Project-LA 25-2013-2014)

Transforming Growth Factor β Signaling Pathway Associated Gene Polymorphisms May Explain Lower Breast Cancer Risk in Western Indian Women

Transforming growth factor β1 (TGFB1) T29C and TGF β receptor type 1 (TGFBR1) 6A/9A polymorphisms have been implicated in the modulation of risk for breast cancer in Caucasian women. We analyzed these polymorphisms and combinations of their genotypes, in pre menopausal breast cancer patients (N = 182) and healthy women (N = 236) from western India as well as in breast cancer patients and healthy women from the Parsi community (N = 48 & 171, respectively). Western Indian women were characterized by a higher frequency of TGFB1*C allele of the TGF β T29C polymorphism (0.48 vs 0.44) and a significantly lower frequency of TGFBR1*6A allele of the TGFBR1 6A/9A polymorphism (0.02 vs 0.068, p<0.01) as compared to healthy Parsi women. A strong protective effect of TGFB1*29C allele was seen in younger western Indian women (<40 yrs; OR = 0.45, 95% CI 0.25–0.81). Compared to healthy women, the strikingly higher frequencies of low or intermediate TGF β signalers in patients suggested a strong influence of the combination of these genotypes on the risk for breast cancer in Parsi women (for intermediate signalers, OR = 4.47 95%CI 1.01–19.69). The frequency of low signalers in Parsi healthy women, while comparable to that reported in Europeans and Americans, was three times higher than that in healthy women from western India (10.6% vs 3.3%, p<0.01). These observations, in conjunction with the low incidence rate of breast cancer in Indian women compared to White women, raise a possibility that the higher frequency of TGFB1*29C allele and lower frequency of TGFBR1*6A allele may represent important genetic determinants that together contribute to a lower risk of breast cancer in western Indian women

Evaluation of chemiluminescence, toluidine blue and histopathology for detection of high risk oral precancerous lesions: A cross-sectional study

<p>Abstract</p> <p>Background</p> <p>Early detection holds the key to an effective control of cancers in general and of oral cancers in particular. However, screening procedures for oral cancer are not straightforward due to procedural requirements as well as feasibility issues, especially in resource-limited countries.</p> <p>Methods</p> <p>We conducted a cross-sectional study to compare the performance of chemiluminescence, toluidine blue and histopathology for detection of high-risk precancerous oral lesions. We evaluated 99 lesions from 55 patients who underwent chemiluminescence and toluidine blue tests along with biopsy and histopathological examination. We studied inter-as well as intra-rater agreement in the histopathological evaluation and then using latent class modeling, we estimated the operating characteristics of these tests in the absence of a reference standard test.</p> <p>Results</p> <p>There was a weak inter-rater agreement (kappa < 0.15) as well as a weak intra-rater reproducibility (Pearson's r = 0.28, intra-class correlation rho = 0.03) in the histopathological evaluation of potentially high-risk precancerous lesions. When compared to histopathology, chemiluminescence and toluidine blue retention had a sensitivity of 1.00 and 0.59, respectively and a specificity of 0.01 and 0.79, respectively. However, latent class analysis indicated a low sensitivity (0.37) and high specificity (0.90) of histopathological evaluation. Toluidine blue had a near perfect high sensitivity and specificity for detection of high-risk lesions.</p> <p>Conclusion</p> <p>In our study, there was variability in the histopathological evaluation of oral precancerous lesions. Our results indicate that toluidine blue retention test may be better suited than chemiluminescence to detect high-risk oral precancerous lesions in a high-prevalence and low-resource setting like India.</p

Thermosensitive in situ gel of Timolol Maleate for the treatment of open angle glaucoma

ABSTRACT The objective of this study was to develop a novel chitosan-chondroitin 6 sulphate insitu gel system for sustained drug delivery of timolol maleate. To increase the low bioavailability and short ocular residence time of timolol maleate eye drops, aqueous solutions of drug in combinations with the polymers were prepared to identify suitable compositions with regard to gel forming properties and drug release behavior. Mixtures of solutions of Pluronic (15-25% w/w), chitosan (0.05-0.3% w/w) of low molecular weight (Mw), chondroitin 6 sulphate (0.05-0.3% w/w) were prepared. Timolol maleate release was determined using a membraneless dissolution model in artificial tear solution up to 8 hours and the samples were analyzed spectrophotometrically at 294 nm. The rheological behavior of solutions in response to dilution or temperature changes and also the phase change temperature (PCT) were determined using a brookfield viscometer. The formulation consisting of 15% Pluronic, 0.05% chondroiitn 6 sulphate and 0.05% low Mw chitosan, depicted highest release efficiency coupled with an acceptable mean release time and is suggested as a suitable ophthalmic preparation for sustained release of timolol maleate. This in situ gel was liquid in non-physiologic conditions (pH 4 and 25ºC) and transferred to the gel form upon exposure to physiologic conditions (pH 7.4 and 37ºC). The PCT of this in situ gel did not change upon dilution

Floating Drug Delivery Systems : Need And Development

Recent scientific and patent literature shows increased interest in academics and industrial research groups regarding the novel dosage forms that can be retained in the stomach for a prolonged and predictable period of time. One of the most feasible approaches for achieving a prolonged and predictable dug delivery profiles in the gastrointestinal tract is to control the gastric residence time, using gastroretentive dosage forms that will provide us with new and important therapeutic options. From the formulation and technological point of view, the floating drug delivery system is considerably easy and logical approach. An attempt has been made in this review article to introduce the readers to the current technological developments in floating drug delivery system.Peer reviewe

Development and In Vitro Evaluation of Buccoadhesive Tablets of Metoprolol Tartrate

Buccoadhesive tablet of metoprolol tartrate was developed to prolong its release and improve bioavailability by avoidance of hepatic first pass metabolism during the treatment of chronic hypertension. The formulations were tested for weight, hardness, friability, content uniformity, swelling index, bioadhesive force and drug release rate. Carbopol 934 P was used as bioadhesive polymer and methocel K4M was added as a matrix former. Backing layer of ethyl cellulose was given to the tablets. Optimised formulation containing carbopol 934 P and methocel K4M in the ratio of 1:1 showed surface pH values in the range of 6 to 7 and 91.50% cumulative release of drug in 10 h. Stability study revealed that the optimized formulation was stable for atleast 3 mo

A Validated HPTLC Method for Determination of Ondansetron in Combination with Omeprazole or Rabeprazole in Solid Dosage Form

A simple, precise, accurate and rapid high performance thin layer chromatographic method has been developed for the simultaneous estimation of ondansetron combinations in solid dosage form with omeprazole and rabeprazole, respectively. The method involved separation of components by TLC on a precoated silica gel 60 F254 using a mixture of dichloromethane:methanol (9:1) as a mobile phase. Detection of spots was carried out at 309 nm and 294 nm for ondansetron with omeprazole and ondansetron with rabeprazole combinations, respectively. The mean retardation factor for ondansetron and omeprazole were found to be 0.42±0.02, 0.54±0.03, respectively while for ondansetron and rabeprazole, 0.41± 0.02 and 0.51±0.02, respectively. The linearity and range was 0.1 to 0.5 μg/spot for three drugs. The method was validated for precision, accuracy and reproducibility

Studies On Formulation And Evaluation Of Ranitidine Floating Tablets

Present investigation highlights the formulation and optimization of floating tablets of ranitidine hydrochloride. Formulations were optimized for type of filler, different viscosity grades of hydroxypropylmethylcellulose and its concentration.Two filler namely Avicel PH 102 and Tablettose 80 were used. Study revealed that type of filler had significant effect on release of drug from hydrophilic matrix tablets (f 2 value 41.30) and floating properties.Three different viscosity grades of hydroxypropylmethylcellulose namely K100 LV, K4M and K15M were used. It was observed that viscosity had a major influence on drug release from hydrophilic matrices as well as on floating properties. Dissolution profiles were subjected various kinetic drug release equations and found that drug release from hydrophilic matrices occurred via diffusion mechanism following square root of time profile (Higuchi equation). Optimized formulation were studied for effect of hardness on floating properties, effect of position of paddle and dissolution medium on drug release as well as accelerated short term stability study. Hardness of tablets had greater influence on floating lag time which might be due to decreased porosity. Position of paddle and types of dissolution medium had no significant effect on drug release. Optimized formulation was found to be stable at 40°/75% RH for the period of three months.Peer reviewe