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1.
J Am Chem Soc ; 146(10): 6604-6617, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38431968

RESUMO

Even though metal-catalyzed enantioselective hydroborations of alkenes have attracted enormous attention, few preparatively useful reactions of α-alkyl acrylic acid derivatives are known, and most use rhodium catalysts. No examples of asymmetric hydroboration of the corresponding α-arylacrylic acid esters are known. In our continuing efforts to search for new applications of earth-abundant cobalt catalysts for broadly applicable organic transformations, we have identified 2-(2-diarylphosphinophenyl)oxazoline ligands and mild reaction conditions for efficient and highly regio- and enantioselective hydroboration of α-alkyl- and α-aryl- acrylates, giving ß-borylated propionates. Since the C-B bonds in these compounds can be readily replaced by C-O, C-N, and C-C bonds, these intermediates could serve as valuable chiral synthons, some from feedstock carbon sources, for the synthesis of propionate-bearing motifs including polyketides and related molecules. Two-step syntheses of "Roche" ester from methyl methacrylate (79%; er 99:1), arguably the most widely used chiral fragment in polyketide synthesis, and tropic acid esters (∼80% yield; er ∼93:7), which are potential intermediates for several medicinally important classes of compounds, illustrate the power of the new methods. Mechanistic studies confirm the requirement of a cationic Co(I) species [(L)Co]+as the viable catalyst in these reactions and rule out the possibility of a [L]Co-H-initiated route, which has been well-established in related hydroborations of other classes of alkenes. A mechanism involving an oxidative migration of a boryl group to the ß-carbon of an η4-coordinated acrylate-cobalt complex is proposed as a plausible route.

3.
Indian J Surg Oncol ; 11(3): 394-397, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33013116

RESUMO

Chemoport is being routinely used to administer chemotherapy, blood, blood products, total parenteral nutrition, and also to draw blood for investigations. We started using chemoport in our institute. We use it exclusively to administer chemotherapy. We analyzed our results of chemoport usage and confirm that the rate of complications associated with chemoport usage is at par with the available literature. We also conclude that with regular use, the intra-op and post-op complications will reduce further.

4.
Int J Food Sci ; 2020: 1696201, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32455128

RESUMO

The screen-printed electrode biosensor was developed for triglyceride determination in coconut milk. The biosensor was developed by adding lipase, glycerol-3-phosphate (GPO), and glycerol kinase (GK), which is immobilized to a gelatin solution. The concentration of triglyceride is found to be linear to the current produced. The developed screen-printed electrode biosensor showed the optimum response for pH 7.0, 45 mg amount of gelatin, 2.5% glutaraldehyde concentration solution. The developed biosensor was able to find triolein concentrations 0.1 to 1.5 mM. The correlation obtained between these two methods was 93% which was found to be good.

5.
Saudi J Anaesth ; 14(4): 436-441, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33447183

RESUMO

CONTEXT: The objective was to study the extent of anaesthetic intervention and its association with systemic comorbidities. The secondary objectives were to estimate the prevalence of systemic comorbidities in age-related cataracts. AIMS: To determine the prevalence of systemic comorbidities in cataract surgery patients and association with anaesthesiologists' intervention. SETTINGS AND DESIGN: Prospective observational study. METHODS AND MATERIALS: The study was done inatertiary care hospital over a period of 3 months. Adult and consenting patients were included and those having sensitivity or toxic reaction to local anaesthetics, uncooperative, and paediatric patients were excluded. STATISTICAL ANALYSIS: The sample size (717) was calculated according to the formula for the finite population. The total number of patients suffering from comorbidities, adverse events during surgery, and events attended by an anesthesiologist with percentages were calculated. RESULTS: Of the 717 patients studied, comorbidities were associated with 385 (53.69%) patients; among which hypertension was most frequent and found in 174 (20.30%). As much as 113 (15.72%) patients had adverse events during surgery and required intervention by the attending anaesthesiologist in which 26 (15.72%) patients required drug administration for stabilization of condition of the patient. CONCLUSIONS: From this study, we conclude that there is a correlation between prevalent comorbidities and active intervention by the attending anaesthesiologist in patients undergoing cataract surgery.

6.
Org Biomol Chem ; 17(18): 4452-4455, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-30990512

RESUMO

This work reports a facile annulation of anthranils with aryloxyethynes or aryl propargyl ethers to construct useful benzofuro[2,3-b]quinoline and 6H-chromeno[3,4-b]quinoline frameworks, respectively; these heterocycles are not readily available from literature methods despite their biological significance. This high atom- and step-economy strategy is highlighted by a broad substrate scope. The reaction mechanism is proposed to proceed through sequential cyclizations among the oxyaryl group, gold carbene and benzaldehyde of the α-imino gold carbene intermediates.

7.
Molecules ; 23(8)2018 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-30096835

RESUMO

The work reports the facile synthesis of novel α-aminophosphonate derivatives coupled with indole-2,3-dione moieties, namely the diethyl(substituted phenyl/heteroaryl)(2-(2-oxoindolin-3-ylidene)hydrazinyl)methylphosphonates derivatives 4(a⁻n). One-pot three component Kabachnik-Fields reactions were used to synthesize these derivatives. The reaction was carried out at room temperature by stirring in presence of ceric ammonium nitrate (CAN) as a green catalyst. The structures of the synthesized compounds were established by spectral studies. The synthesized derivatives 4(a⁻n) were evaluated for their in vitro anticancer activity against six human cancer cell lines by the SRB assay method. The cancer cell lines used in this research work are SK-MEL-2 (melanoma), MCF-7 (breast cancer), IMR-32 (neuroblastoma) MG-63 (human osteosarcoma), HT-29 (human colon cancer) and Hep-G2 (human hepatoma). All the synthesized derivatives inhibited the cell proliferation. Importantly, all the target compounds showed no cytotoxicity towards normal tissue cells (GI50 > 250 µM). A docking study was performed to predict the mode of action. Docking results indicate that the compounds have good binding with the enzyme tyrosine kinase as well as with microtubules, which makes them dual inhibitors. The result of in-silico bioavailability studies suggests that the compounds from the present series have good oral drug-like properties and are non-toxic in nature. In vivo acute oral toxicity study results indicate that the compounds can be considered safe, and therefore could be developed in the future as good anticancer agents or as leads for the design and synthesis of novel anticancer agents.


Assuntos
Antineoplásicos/uso terapêutico , Química Verde/métodos , Modelos Moleculares , Organofosfonatos/uso terapêutico , Administração Oral , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacocinética , Comportamento Animal , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Imageamento Tridimensional , Camundongos , Simulação de Acoplamento Molecular , Organofosfonatos/síntese química , Organofosfonatos/química , Organofosfonatos/farmacocinética , Testes de Toxicidade Aguda
8.
Indian J Endocrinol Metab ; 22(4): 511-514, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30148099

RESUMO

CONTEXT: To find a single time point during clonidine stimulation test (CST), with highest diagnostic value to rule out growth hormone deficiency (GHD). SETTINGS AND DESIGN: This is a retrospective study of 79 CSTs carried out in a tertiary care center in India. MATERIALS AND METHODS: A cohort of 79 children with unexplained short stature was divided into two groups: GHD and non-GHD. Any one stimulated growth hormone (GH) level >10 ng/mL was used to rule out GHD. Diagnostic accuracy of not only single time points but also time points in pairs was calculated. STATISTICAL ANALYSIS: The data were analyzed using SPSS statistical software 22.0. Descriptive statistics were used for analyzing demographic data. Mode for time to peak GH was calculated in each group. The specificity and false positive rates at each time point as well as combined time points were determined. RESULTS: Assaying a single sample at 60 min after clonidine resulted in 20.5% false positive tests with specificity of 79.5%. Addition of the 90 min sample increased specificity to 92.3%. CONCLUSION: The 60 min sample after clonidine stimulation was the best single sample to rule out GH deficiency. Combined sampling at 60 min + 90 min is economical and less cumbersome, with minimal compromise on the specificity.

9.
J Food Sci Technol ; 55(7): 2504-2513, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30042566

RESUMO

Present study was conducted to evaluate the effect of Power ultrasound, on dehulling efficiency, dhal yield, dehulling loss and total colour difference of black gram using response surface methodology. Nine treatments were performed with variation in ultrasound power 343-525 W and treatment time 1-3.5 h. It was observed that ultrasound treatment significantly improved the dehulling efficiency and dhal yield of the black gram and reduced the dehulling loss. The optimized treatment condition obtained for optimum dehulling yield (75.71%), dhal yield (74.63%) dehulling loss (12.72%), and total colour difference (5.08) was ultrasound power of 513.39 W and exposure time of 2.12 h. Moreover the blackgram pretreated with ultrasound required lesser cooking time when compared to soaked alone sample. The SEM analysis revealed the significant effect of ultrasound on the blackgram kernel which led to uniform cavitation of the surface of the kernel compared to the soaked sample without ultrasound treatment. In food industry blackgram is preprocessed i.e. soaked and cooked to produce various soups, canned products, batter, snack foods etc. Hence ultrasonic treatment can be applied to improve and facilitate a faster dehulling efficiency, with added advantage of increased soaking rate and a decrease in the cooking time for blackgram.

10.
Angew Chem Int Ed Engl ; 57(45): 14878-14882, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30047589

RESUMO

The catalytic formation of gold enolates from alkynes, nitrones, and nucleophiles is described, and their Mannich reactions result in nucleophile-directed chemoselectivity through cooperative catalysis. For 1-alkyn-4-ols and 2-ethynylphenols, their gold-catalyzed nitrone oxidations afforded N-containing dihydrofuran-3(2H)-ones with syn selectivity. The mechanism involves the Mannich reactions of gold enolates with imines through an O-H-N hydrogen-bonding motif. For aryloxyethynes, their gold enolates react selectively with nitrones to deliver 3-alkylidenebenzofuran-2-ones, as controlled by a C-H-O hydrogen-bonding motif.

11.
Sci Rep ; 8(1): 6832, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29717180

RESUMO

Ferti-fortification of wheat with zinc, an essential micronutrient is one of the strategies for combating 'hidden hunger' in a large proportion of people all over the world. During fertilization, application of large quantities of micronutrients often results in nutrient wastage and subsequent environmental pollution. Here, we report zinc complexed chitosan nanoparticles (Zn-CNP) for ferti-fortification of durum wheat in field-scale experiments. The efficacy of Zn-CNP was assessed vis-à-vis conventionally applied ZnSO4 (0.2%; 400 mgL-1 zinc) in two durum wheat genotypes (MACS 3125, an indigenous high yielding genotype and UC 1114, a genotype containing the Gpc-B1gene). The observed grain zinc enrichment using Zn-CNP nanocarrier (~36%) and conventional ZnSO4 (~50%) were comparable, despite 10 folds less zinc (40 mgL-1) used in the former. Nanofertilizer application increased grain zinc content without affecting grain yield, protein content, spikelets per spike, thousand kernel weight, etc. Grain zinc enrichment observed in the four-year field trials on plots with varying soil zinc content was consistent, proving the utility of Zn-CNP as a novel nanofertilizer which enhanced fertilizer use efficiency. Our work describes a new paradigm in micronutrient fortification, viz. 'use nanofertilizers at the right place, right time and in right doses'.


Assuntos
Quitosana/química , Fertilizantes/análise , Micronutrientes , Nanopartículas/química , Triticum/química , Triticum/genética , Zinco/química , Análise de Variância , Grão Comestível/química , Genótipo , Ferro/química , Solo/química , Triticum/classificação , Sulfato de Zinco/química
12.
Carbohydr Polym ; 165: 394-401, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28363565

RESUMO

Cultivation of cereals in zinc deficient soils leads to declined nutritional quality of grain. Zinc deficiency in humans is a consequence of consumption of micronutrient deficient cereals as staple food. To achieve an increase in zinc density in grain, we evaluated zinc complexed chitosan nanoparticles (Zn-CNP) as a potential 'nanocarrier' suited for foliar fertilization. Zn-CNP were synthesized using tri-polyphosphate as a cross-linker. Spherical Zn-CNP (diameter 250-300nm) were positively charged (zeta potential, +42.34mV) and contained ∼20mg Zn/g (w/w). Plant growth in zinc deficient sand media, followed by foliar application of Zn-CNP (twice-a-week, for 5 weeks) after anthesis resulted in 27 and 42% increase in grain zinc content of MACS 3125 and UC1114 (durum wheat cultivars) respectively. Translocation of zinc ions from foliar applied Zn-CNP into the leaf and seed tissue was demonstrated using zinquin and dithizone stains, respectively. The study indicates the suitability of chitosan-based nanocarriers in agronomic biofortification.


Assuntos
Quitosana , Fertilizantes , Micronutrientes/administração & dosagem , Triticum/metabolismo , Zinco/química , Nanopartículas , Folhas de Planta/metabolismo
13.
Eur J Med Chem ; 127: 459-469, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28103537

RESUMO

A number of hybrid molecules containing thienopyrimidinones and thiouracil moieties were designed, synthesized and tested against Mycobacterium tuberculosis H37Ra wherein it was observed that the compounds 11-14 exhibited antitubercular activity in vitro (MIC 7.6-19.1 µg/mL, 12-35 µM) against dormant stage while the compound 15 exhibited antitubercular activity in vitro against dormant (MIC 23.4 µg/mL, 41 µM) as well as active (MIC 25.4 µg/mL, 45 µM) stage. Structural modifications of the compound 15 were carried out to study the structure-activity relationship and it was observed that the compound 18 exhibited antitubercular activity comparable to the compound 15. Cytotoxicity studies revealed that these molecules were non-toxic. The docking study of the compound 15 showed that there was binding with the active site of mycobacterial pantothenate synthetase. Further docking studies led to the synthesis of the compounds 16 and 17 and the antitubercular activity screening results showed that these compounds have significant antitubercular activity. The compounds 15-18 (MIC 11-29 µg/mL, 19-51 µM) can be used as starting points for further optimization. The synthetic strategies used in the present work have potential to prepare a large number of compounds for further refinement of structures and the present results will be very useful in the development of a new class of antimycobacterial agents.


Assuntos
Antituberculosos/química , Antituberculosos/farmacologia , Simulação de Acoplamento Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Pirimidinas/química , Tiouracila/química , Tiouracila/farmacologia , Antituberculosos/metabolismo , Antituberculosos/toxicidade , Domínio Catalítico , Linhagem Celular Tumoral , Humanos , Testes de Sensibilidade Microbiana , Peptídeo Sintases/química , Peptídeo Sintases/metabolismo , Relação Estrutura-Atividade , Tiouracila/metabolismo , Tiouracila/toxicidade
14.
Chemosphere ; 171: 240-247, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28024209

RESUMO

In this study, a soil pot experiment was conducted to investigate the changes in photosynthesis and antioxidative enzymes in two rice varieties (Shendao 6 and Shennong 265) supplied with iron (Fe), cadmium (Cd), and Fe and Cd together. The concentrations of Fe and Cd in the soil were 0, 1.0 g Fe·kg-1 and 0, 2.0 mg Cd·kg-1, respectively. Photosynthetic indices and antioxidative enzyme activities were recorded at different rice growth stages. At the early stage, Cd showed a transient stimulatory effect on the photosynthetic rate of Shennong 265. For Shendao 6, however, Cd showed a transient stimulatory effect on photosynthetic rate, intercellular CO2 concentration, stomatal conductance and transpiration efficiency. In addition, the results show that Cd can also enhance the superoxide dismutase (SOD) and peroxidase (POD) activities, but reduce the malondialdehyde (MDA) and soluble protein contents in the two rice cultivars. Subsequently, Cd starts to inhibit photosynthesis and SOD activity until the ripening stage, causing the lowest photosynthetic rate and SOD activity at this stage. In contrast, Fe alleviates the Cd-induced changes at earlier or later growth stage. Notably at the later growth stage, the results show that the interaction between Fe and Cd increases the SOD and catalase (CAT) activities, while decreasing the lipid peroxidation and promoting photosynthesis. As a result, it ultimately increases the biomass. The results from this study suggest that Fe (as Fe fertilizer) is a promising alternative for agricultural use to enhance the plant development and, simultaneously, to reduce Cd toxicity in extensively polluted soils.


Assuntos
Antioxidantes/metabolismo , Cádmio/farmacologia , Ferro/farmacologia , Oryza/metabolismo , Fotossíntese/efeitos dos fármacos , Biomassa , Fertilizantes , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/metabolismo , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Superóxido Dismutase/metabolismo
15.
Indian J Endocrinol Metab ; 20(1): 97-100, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26904476

RESUMO

INTRODUCTION: The prevalence of autoimmune thyroid disease (AITD) is 10-12% in the general population worldwide. Among various disorders co-existing with AITD, the concomitance of celiac disease (CD) with AITD results in poor absorption of thyroid medications and results in higher doses of the same. Institution of gluten-free diet (GFD) in this cohort helps reduce medication doses. AIM: To screen patients with AITD for the presence of celiac autoimmunity (CA). MATERIALS AND METHODS: A total of 280 consecutive patients with AITD attending the thyroid Out-patient Department of a tertiary care hospital were screened for the presence of tissue transglutaminase antibodies (immunoglobulin A tissue transglutaminase). Those with a positive titer (but < 10 times the upper limit of normal) underwent upper gastrointestinal endoscopy and duodenal mucosal biopsy for the diagnosis of CD, followed by institution of GFD in confirmed cases. RESULTS: Of a total of 280 (182 females and 98 males) patients with AITD screened, 24 (8.6%) turned out to be positive for CA. Of 24 (8.6%), 15 (8.24%) females and 9 (9.18%) males were positive for CA. There was no statistically significant difference in the thyroxine doses required for normalization of thyroid function and the weight of the patients in CA positive and CA negative patients. CONCLUSIONS: The prevalence of CD in patients with AITD is much greater than in the general population. This forms the basis for screening patients with AITD for presence of CD.

17.
Indian J Endocrinol Metab ; 19(5): 680-2, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26425483

RESUMO

The article is one in the series of articles related to glycaemic management in festivals across all religions in India. The article discusses issues in glycaemic management among Parsi culture, which represent a small but ever important group of Indian population.

19.
Indian J Endocrinol Metab ; 18(4): 511-5, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25143908

RESUMO

INTRODUCTION: Vitamin D (VitD) classically recognized for its role in the musculoskeletal system, has been implicated in myriad of conditions such as diabetes, immune dysfunction, cancers, heart disease, metabolic syndrome, etc. We studied the role of VitD in acute care setting and its correlation with mortality. MATERIALS AND METHODS: A total of 85 consecutive consenting patients admitted in medical intensive care unit of tertiary care hospital who fulfilled the inclusion criteria were included. All patients were evaluated clinically, and blood samples were collected for hemogram, biochemical investigations including serum calcium, phosphorus, alkaline phosphatase, magnesium, along with 25(OH) VitD, 1,25(OH) VitD and intact parathormone levels. Simplified acute physiology score (SAPS II) was calculated for all patients. RESULTS: VitD was deficient (<30 ng/ml) in 27 patients (32%). The overall mortality was more in VitD deficient group as compared to VitD sufficient group (74 vs. 41%; P < 0.05). The actual mortality in VitD deficient group was higher than the mortality predicted by SAPS II score (50 vs. 74%; P < 0.0507). VitD deficiency was also associated with more mortality among those requiring ventilator support (95% vs. 40%; P < 0.05) as well as with higher blood glucose (124.5 ± 29.7 vs. 94.8 ± 19.8: P < 0.01) levels. CONCLUSION: VitD deficiency was associated with increased mortality, poor ventilator outcomes, and increased blood glucose in critically ill patients.

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