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PublicationLetter Linear scleroderma with partial anonychia(2009) Sanjay Singh; Surendra Kumar[No abstract available]PublicationArticle Metabolic drift as internal defense against drought in crop plants: Evidence unlocked from rice cultivars(2009) Sanjay Singh; T.N. Singh; J.S. ChauhanWe chose three rice (Oryza sativa L.) cultivars to understand the physiology of crop adaptation to drought. Under water stress, leaves curled up and rolled in and the water potential declined. 'Baranideep' maintained relatively higher water potential (-1.8 MPa) than irrigated hybrid rice cv. 'NDRH-2' (-2.0 MPa) and aquatic cv. 'Jal Lahri' (-2.6 MPa). The drought-induced stress caused variation in tissue-specific expressions of metabolic drift in sugar and starch, protein, and nitrogen, and stay-green traits. The genotypic differences in sugar levels varied to the extent of 130 mg g-1 fresh wt (f.w.) in 'Jal Lahri' >120 mg in 'NDRH-2' 114> mg in 'Baranideep', while initial starch contents were 263 mg >252 mg >230 mg in these cultivars, respectively. Sugar levels rose by 23% in cv. 'Jal Lahri', 16% in 'NDRH-2' and 17% in cv. 'Baranideep', whereas starch contents declined by 17%, 13% and 12.5%, respectively. The net chlorophyll concentrations were highest in 'NDRH-2' (up to 1,325 μg g-1 f.w.), followed by 'Jal Lahri' (1,050 μg) and 'Baranideep' (920 μg) under normal conditions, but declined during water stress; 'NDRH-2' maintained its superiority over the other varieties. Under water stress, chlorophyll a:b ratios increased appreciably in 'Baranideep'; 'Jal Lahri' registered the largest difference between watered and stressed plants. 'Baranideep' accumulated the largest amount of proline (9.25 mg g-1 dry wt) during water stress. Under non-stress conditions, 'NDRH-2' had the highest nitrogen content in leaves (2.15%), followed by 'Jal Lahri' (1.85%) and 'Baranideep' (1.75%). The cv. 'NDRH-2' retained more nitrogen in leaves than other cultivars. 'Jal Lahri' retained the highest nitrogen in the shoot. Nevertheless, under drought stress, the shoot protein was highest in 'NDRH-2' (3.15%), followed by 'Baranideep' (2.80%) and 'Jal Lahri' (2.65%). These tissue-specific metabolic drifts are plant's life-support system and serve as a defense against drought.PublicationLetter Scientific precision in titles of research papers published in three dermatology journals(2009) Sanjay Singh; Rahul Chaudhary; Swastika Suvirya[No abstract available]PublicationLetter Pulse therapy for pemphigus: The burden of proof(2009) Sanjay Singh; Rahul Chaudhary[No abstract available]PublicationArticle Hypopyon sign in pemphigus vulgaris and pemphigus foliaceus(2009) Sanjay Singh; Sanjeev Gupta; Rahul Chaudhary[No abstract available]PublicationReview Lipid - An emerging platform for oral delivery of drugs with poor bioavailability(2009) Subhashis Chakraborty; Dali Shukla; Brahmeshwar Mishra; Sanjay SinghThe sole objective of pharmaceutical science is to design successful dosage forms which fulfill the therapeutic needs of the patients effectively. Development of new drug entities is posing real challenge to formulators, particularly due to their poor aqueous solubility which in turn is also a major factor responsible for their poor oral bioavailability. Lipids as carriers, in their various forms, have the potential of providing endless opportunities in the area of drug delivery due to their ability to enhance gastrointestinal solubilization and absorption via selective lymphatic uptake of poorly bioavailable drugs. These properties can be harvested to improve the therapeutic efficacy of the drugs with low bioavailability, as well as to reduce their effective dose requirement. The present communication embodies an in-depth discussion on the role of lipids (both endogenous and exogenous) in bioavailability enhancement of poorly soluble drugs, mechanisms involved therein, approaches in the design of lipid-based oral drug delivery systems with particular emphasis on solid dosage forms, understanding of morphological characteristics of lipids upon digestion, in vitro lipid digestion models, in vivo studies and in vitro-in vivo correlation. © 2009 Elsevier B.V. All rights reserved.PublicationLetter A case report of tinea nigra from North India(2009) Ragini Tilak; Sanjay Singh; Pradyot Prakash; Dharmendra Singh; Anil Gulati[No abstract available]PublicationArticle Development and biopharmaceutical evaluation of extended release formulation of tramadol hydrochloride based on osmotic technology(Croatian Pharmaceutical Society, 2009) Pramod Kumar; Sanjay Singh; Brahmeshwar MishraExtended release formulation of tramadol hydrochloride (TRH) based on osmotic technology was developed and evaluated. Target release profile was selected and different variables were optimized to achieve it. Formulation variables such as the level of swellable polymer, plasticizer and the coat thickness of semipermeable membrane (SPM) were found to markedly affect drug release. TRH release was directly proportional to the levels of plasticizer but inversely proportional to the levels of swellable polymer and coat thickness of SPM. Drug release from developed formulations was independent of pH and agitation intensity but dependent on osmotic pressure of the release media. In vivo study was also performed on six healthy human volunteers and various pharmacokinetic parameters (cmax, tmax, AUC 0-24, MRT) and relative bioavailability were calculated. The in vitro and in vivo results were compared with the performance of two commercial TRH tablets. The developed formulation provided more prolonged and controlled TRH release compared to the marketed formulation. In vitro-in vivo correlation (IVIVC) was analyzed according to the Wagner-Nelson method. The optimized formulation (batch IVB) exhibited good IVIV correlation (R = 0.9750). The manufacturing procedure was found to be reproducible and formulations were stable over 6 months of accelerated stability testing.PublicationArticle PLGA nanoparticle formulations of risperidone: preparation and neuropharmacological evaluation(2009) Madaswamy S. Muthu; Manoj K. Rawat; Amit Mishra; Sanjay SinghThe aim of this work was to develop extended-release poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles of risperidone and thermal-responsive in situ gel containing risperidone nanoparticles for parenteral (subcutaneous) delivery and to reduce the dose-dependent extrapyramidal side effects of risperidone. PLGA nanoparticles of risperidone were designed by nanoprecipitation method using polymeric stabilizer (Poloxamer 407). The prepared nanoparticles were characterized for particle size by photon correlation spectroscopy and atomic force microscopy. Poloxamer 407-based in situ gel containing PLGA nanoparticles of risperidone was prepared by modified cold method to control the initial rapid release from the nanoparticles. The in vivo efficacy (antipsychotic effect) of prepared formulations (nanoparticles and in situ gel containing nanoparticles) was studied by administering them subcutaneously to mice. Extrapyramidal side effects of the formulations were also studied. The particle size of the prepared nanoparticles ranged between 85 and 219 nm. About 89% to 95% drug encapsulation efficiency was achieved when risperidone was loaded at 1.7% to 8.3% by weight of the polymer. During in vivo studies prepared risperidone formulations showed an antipsychotic effect that was significantly prolonged over that of risperidone solution for up to 72 hours with fewer extrapyramidal side effects. The prolonged effect of risperidone was obtained from the risperidone formulations administered subcutaneously, and this may improve the treatment of psychotic disorders by dose reduction. From the Clinical Editor: The development of extended-release poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles of risperidone is reported in this paper, along with the development of thermal-responsive in situ gel containing risperidone nanoparticles for parenteral (subcutaneous) delivery and to reduce the dose-dependent extrapyramidal side effects. In vivo studies showed a significantly prolonged antipsychotic effect with fewer extrapyramidal side effects. © 2009 Elsevier Inc. All rights reserved.PublicationArticle A case of Actinomycotic mycetoma involving the right foot(Journal of Infection in Developing Countries, 2009) Ragini Tilak; Sanjay Singh; Atul Garg; Jaya Bassi; Vijai Tilak; Anil K. GulatiA 45-year-old male presented with history of multiple swellings over the foot with sinuses discharging seropurulent pus. Actinomadura madurae was demonstrated and identified by microbiological culture from the pus obtained directly of the lesion. This case is reported to emphasize the importance of laboratory diagnosis in the management and assessment of the prognosis of such cases.