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S P Patil

Publications and source records attributed to S P Patil.

7 recordsLinked to original sources
PubMed2003

Selective acylation of 2 methoxynaphthalene by large pore zeolites: catalyst selection through molecular modeling.

The selective acylation of 2-methoxynaphthalene (2-MON) is commercially very important to produce selectively 2-acyl-6-methoxynaphthalene (2,6-AMON), which is a precursor to Naproxen, an anti-inflammatory drug. Most of the laboratory investigations conducted with different solid acids show that the undesirable products are formed in large quantities. Thus, various molecular modeling techniques were used to investigate selectivity towards desired 2,6-AMON isomer over undesired 1,2-AMON, in four large-pore zeolites, namely, mordenite (MOR), zeolite L (LTL), zeolite beta (BEA) and ITQ-7 (ISV). The qualitative results were obtained by using simple molecular graphics (MG) and structural fitting approach. The quantitative results were obtained by incorporating the interaction of atoms of the molecules and those of the zeolite frameworks. From diffusion energy profile calculations the diffusion energy barriers for self-diffusion of 2-MON and the acylated isomers were obtained. From these energy barrier values the selectivity offered by zeolites towards desired product was determined and it was found to be in the order of ISV>BEA>MOR>LTL. Hybrid Quantum Mechanics-Molecular Mechanics (QM/MM) approach was used to study the effect of Brønsted acidity on the activity and selectivity offered by zeolites. The interaction of the reactant and product species with the acidic protons at T3 and T9 sites in BEA, having different acidities was studied by this method. The QM energy values indicate that acidity affected the catalytic activity but not the regioselectivity towards the desired 2,6-AMON isomer.

Journal Article↗
PubMed2003

Hypercapnic duty cycle is an intermediate physiological phenotype linked to mouse chromosome 5.

We hypothesized that upper airway obstruction (UAO) leads to a compensatory increase in the duty cycle [ratio of inspiratory time to respiratory cycle length (Ti/Tt)], which is determined by genetic factors. We examined the compensatory Ti/Tt responses to 1). UAO and hypercapnia among normal individuals and 2). hypercapnia in different inbred strains, C3H/HeJ (C3) and C57BL/6J (B6), and their first- and second-generation (F2) offspring. 3). We then used the compensatory Ti/Tt response in the F2 to determine genetic linkage to the mouse genome. First, normal individuals exhibited a similar increase in the Ti/Tt during periods of hypercapnia (0.11 +/- 0.07) and UAO (0.09 +/- 0.06) compared with unobstructed breathing (P < 0.01). Second, the F2 offspring of C3 and B6 progenitors showed an average Ti/Tt response to 3% CO2 (0.42 +/- 0.005%) that was significantly (P < 0.01) greater than that of the two progenitors. Third, with a peak log of the odds ratio score of 4.4, Ti/Tt responses of F2 offspring are genetically linked to an interval between 58 and 64 centimorgans (cM) on mouse chromosome 5. One gene in the interval, Dagk4 at 57 cM, is polymorphic for C3 and B6 mice. Two other genes, Adrbk2 at 60 cM and Nos1 at 65 cM, have biological plausibility in mechanisms of upper airway patency and chemosensitivity, respectively. In summary, Ti/Tt may serve as an intermediate physiological phenotype for compensatory neuromuscular response mechanisms for maintaining ventilation in the face of UAO and hypoventilation and to help target specific candidate genes that may play a role in the expression of sleep-disordered breathing.

Adult↗
PubMed2002

Determination of celecoxib in pharmaceutical formulations using UV spectrophotometry and liquid chromatography.

A new UV spectrophotometric method (UV method) and a reversed phase liquid chromatographic method (LC method) for the quantitative estimation of celecoxib, a selective COX-2 inhibitor, in pure form and in solid dosage form were developed in the present study. The linear regression equations obtained by least square regression method, were Abs=4.949 x 10(-2).Conc. (in microg/ml)+1.110 x 10(-2) for the UV method and Area under the curve=5.340 x 10(1).Conc. (in ng/ml)+3.144 x 10(2) for the LC method, respectively. The detection limit, as per the error propagation theory, was found to be 0.26 microg/ml and 25 ng/ml, respectively, for the UV and LC methods. The developed methods were employed with a high degree of precision and accuracy for the estimation of total drug content in three commercial capsule formulations of celecoxib. The results of analysis were treated statistically, as per International Conference on Harmonisation (ICH) guidelines for validation of analytical procedures, and by recovery studies. The results were found to be accurate, reproducible and free from interference and better than the earlier reported methods.

Calibration↗
PubMed2001

Chickpea: a major food allergen in the Indian subcontinent and its clinical and immunochemical correlation.

BACKGROUND: The food allergy pattern of a country is influenced by the foods most commonly consumed. In India, the majority of the population consumes a vegetarian diet made up of pulse (legumes), cereals, and vegetables. In contrast to many western countries, chickpea preparations are consumed in large quantities in India. This study reports for the first time chickpea hypersensitivity reactions diagnosed with in vivo and in vitro tests. METHODS: One thousand four hundred patients visiting allergy clinics were randomly selected for the study. Those patients reporting an allergic reaction on every occasion after eating chickpea were considered history-positive. Modified prick tests were performed with chickpea and other members of the legume family on all these patients. The claims of the history-positive patients were verified with double-blind, placebo-controlled food challenges (DBPCFCs). Proteins in chickpea extracts were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and transferred on nitrocellulose paper. Serum specimens from history-positive patients were analyzed by immunoblot and ELISA. To verify the IgE specificity, an immunoblot inhibition assay was also performed. RESULTS: Of the 1,400 patients screened, 142 patients were history-positive to some food and 59 of these implicated chickpeas. Forty-one patients were skin test-positive and 31 were DBPCFC-positive for chickpea. The predominant symptoms after chickpea ingestion were respiratory. The ELISA results did not correlate well with the DBPCFC results; however, the skin test results correlated with DBPCFC in 75% of patients. Immunoblot analysis showed that 70, 64, 35, and 26 kD proteins were major allergens. CONCLUSIONS: Chickpea is an important source of allergen that can cause IgE-mediated hypersensitivity reactions ranging from rhinitis to anaphylaxis.

Adolescent↗
PubMed1997

Allergy to fenugreek (Trigonella foenum graecum).

BACKGROUND: Allergic reactions after consumption of spices are well-known. In Asia, fenugreek seeds are consumed as spices and also as medicines. Literature survey carried out does not reveal reports of allergic reactions to fenugreek. In our survey carried out on patients with food allergy, we found two cases of severe allergy to fenugreek. METHODS: We report here two cases of immediate allergy following ingestion, inhalation, and external application of fenugreek seed powder. In the first case, inhalation of the fenugreek seed powder resulted in rhinorrhea, wheezing, and fainting. The second case was of a patient with chronic asthma who developed numbness of head, facial angioedema, and wheezing after application of fenugreek paste to her scalp as a treatment for dandruff. Skin scratch test was performed with fenugreek and other members of the Leguminosae family as fenugreek also belongs to Leguminosae. Objective evidence of the reaction was obtained by conducting double-blind placebo-controlled challenges (DBPCFC). For detecting IgE binding by immunoblotting method, the proteins of the fenugreek extract were resolved using sodium dodecyl sulphate polyacrylamide gel electrophoresis. RESULTS: Skin scratch tests for the patients revealed strong sensitivity to fenugreek and chickpeas. None of the controls showed such response with fenugreek extract. During DBPCFC, both patients showed > 20% drop in peak flow rate after consumption of fenugreek and chickpea. Immunoblots demonstrated binding of specific IgE from the patients' sera with the protein from extracts between 20 kD to 70 kD bands. CONCLUSION: This case report has enlarged the list of food allergens with the addition of fenugreek.

Adult↗