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1.
Sci Rep ; 13(1): 10393, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37369685

RESUMO

For the first time, electrochemical methods are utilized to study the response of tubulin monomers (extracted from plant source such as Green Peas: Arachis Hypogea) towards charge perturbations in the form of conductivity, conformational changes via self-assembly and adsorption on Au surface. The obtained dimerization and surface adsorption energetics of the tubulins from Cyclic Voltammetry agree well with the literature value of 6.9 and 14.9 kCal/mol for lateral and longitudinal bond formation energy respectively. In addition to the effects of charge perturbations on change in structure, ionic and electronic conductivity of tubulin with increasing load are investigated and found to be 1.25 Sm-1 and 2.89 mSm-1 respectively. The electronic conductivity is 1.93 times higher than the literature value of 1.5 mSm-1, demonstrating the fact that the microtubules (dimer of tubulins, MTs) from plant source can be used as a semiconductor electrode material in energy conversion and storage applications. Thus, motivated by the Monte Carlo simulation and electrochemical results the MTs extracted from plant source are used as cathode material for energy storage device such as Bio-battery and the Galvanostatic Charge/Discharge studies are carried out in coin cell configuration. The configuration of the bio-battery cell is as follows: Al/CB//PP-1M KCl//MTs/SS; where SS and Al are used as current collectors for cathode and anode respectively, Polypropylene (PP) membrane soaked in 1M KCl as electrolyte and Carbon Black (CB) is the anode material. Another configuration of the cell would be replacement of CB by biopolymer such as ethyl cellulose anode (Al/EC/PP-1M KCl/MTs/SS).

2.
Med Biol Eng Comput ; 61(1): 205-227, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36348143

RESUMO

Medical images of patients must be securely transmitted and kept private in telemedicine. To secure such medical images, this paper proposes a single round chaotic image encryption scheme based on a permutation-diffusion structure. A combined chaotic key generator (CCKG) is proposed to enhance key sensitivity and generation in order to improve the security of medical images to be encrypted. CCKG is used to produce the initial seeds for the fractional order chaotic system (FOCS) and Lorenz system (LS) for the permutation and diffusion processes, respectively. CCKG together with proposed permutation and diffusion methods enhances cipher image security in single round. Using zigzag transform (ZT) scanning, the plain image is first permuted block by block. The type of scanning used on each block is heavily influenced by the ZT selection from FOCS and LS. Following block-wise permutation, the permutation order (PO) generated from LS performs overall permutation. Based on the pixel positions, the overall permuted image is divided into odd and even parts. Then these parts of the images are diffused separately by the random pixel matrices generated by LS and FOCS. The cipher image is formed by combining the odd and even parts after diffusion. Secret key analysis, statistical analysis, differential attack analysis, and simulations confirm that with a single round of image encryption, the proposed system is competent, robust and effective.


Assuntos
Segurança Computacional , Telemedicina , Humanos , Algoritmos , Telemedicina/métodos , Difusão
3.
Phys Chem Chem Phys ; 24(26): 16112-16124, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35748394

RESUMO

The lithiation mechanism of Ag2O with one and two Li atoms per unit cell carried out using density functional theory (DFT) studies indicate the adsorption of one Li atom at the tetrahedral interstitial site (TIS) as the most stable one with the formation of the Li-Ag2O compound. PDOS plots depict the hybridization of Li 2s with O 2p and Ag 5s states, resulting in the formation of both Li-O and Li-Ag bonds. Also, the Bader charge analysis validates the bonding of Li at TIS with both Ag and O atoms. The band structure plots showcase a surge in electronic conductivity, accounting for the metallic transition of Ag2O with the addition of Li. The difference in the charge distribution between the pairs of surface and subsurface silver atoms in charge density difference plots (CDDP) reveal the incorporation of Li, invoking charge inequivalence in addition to the symmetry inequivalence in the optimized structure. In the case of two Li atoms, Li placed on the top of oxygen (Otop) and at the subsurface of silver (Agss) was found to be the most stable structure with the formation of two strong Li-O bonds, indicating the feasibility of the conversion mechanism. The increase in the Bader charge of O (-1.28e) as well as CDDP establish the formation of Li2O by the conversion mechanism. Thus, the increase in the Li+ ion concentration becomes the deciding factor for the transition of the lithiation mechanism from Li-Ag2O compound formation to the conversion mechanism. The molecular dynamics (MD) simulations feature Li as an "antisite defect producing guest", leading to the formation of Li-O bonds with a concomitant reduction in the number of Ag-O bonds as a function of time. This confirms a shift in the reaction kinetics from the formation of Li-Ag2O to the conversion mechanism.

4.
J Pharm Sci ; 110(11): 3726-3734, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34363840

RESUMO

The present study aims to comprehend the adsorption behavior of a set of anticancer drugs namely 5-fluorouracil (5-FU), doxorubicin and daunorubicin on ZnO nanoparticles (ZnO NPs) proposed as drug delivery systems employing solid state (ss) NMR, FTIR and Cyclic Voltammetry (CV) analysis. FTIR and 1H MAS ssNMR data recorded for bare ZnO nanoparticle confirmed the presence of adsorbed -OH groups on the surface. 13C CP-MAS NMR spectra recorded for free and ZnO surface adsorbed drug samples exhibited considerable line broadening and chemical shift changes that complemented our earlier report on UV-DRS and XRD data of surface adsorption in case of 5-FU. Moreover, a remarkable enhancement of 13C signal intensity in case of loaded 5-FU was observed. This clearly indicated rigid nature of the drug on the surface allowing efficient transfer of 1H polarization from the hetero nitrogen of 5-FU to ZnO to form surface hydroxyl (-OH) groups and the same has been observed in the quantum chemical calculations. To further analyze the motional dynamics of the surface adsorbed 5-FU, longitudinal relaxation times (T1) were quantified employing Torchia method that revealed significant enhancement of 13C relaxation rate of adsorbed 5-FU. The enhanced rate suggested an effective role of quadrupolar contribution from 67Zn to the 13C relaxation mechanism of ZnO_5-FU. The heterogeneous rate constant (khet), average free energy of activation (∆G≠) and point of zero charge (PZC) measured for free and drug loaded ZnO NPs samples using CV further support the SS-NMR results.


Assuntos
Antineoplásicos , Nanopartículas , Óxido de Zinco , Adsorção , Doxorrubicina
5.
Open Biol ; 11(6): 200288, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34062097

RESUMO

We describe the epidemiological characteristics and associated risk factors of those presenting at a large testing centre for SARS-CoV-2 infection. This is a retrospective record review of individuals who underwent SARS-CoV-2 testing by reverse transcription-polymerase chain reaction (RT-PCR) at a high-throughput national-level government facility located in the north of India. Samples collected from 6 April to 31 December 2020 are included in this work and represent four highly populous regions. Additionally, there was a prospective follow-up of 1729 cases through telephone interviews from 25 May 2020 to 20 June 2020. Descriptive analysis has been performed for profiling clinic-epidemiological aspects of suspect cases. Multivariable logistic regression analysis was undertaken to determine risk factors that are associated with SARS-CoV-2 test positivity and symptom status. A total of 125 600 participants' details have been included in this report. The mean (s.d.) age of the participants was 33.1 (±15.3) years and 66% were male. Among these tested, 9515 (7.6%) were positive for COVID-19. A large proportion of positive cases were asymptomatic. In symptomatic positive cases, the commonest symptoms were cough and fever. Increasing age (groups 20-59 and ≥60 years compared to age group less than 5 years), male sex, history of international travel, symptoms for SARS-CoV-2, and participants from Delhi and Madhya Pradesh were positively associated with SARS-CoV-2 test positivity. Having co-morbidity, risk behaviours and intra-familial positivity were associated with a positive odds ratio for exhibiting SARS-CoV-2 symptoms. Intensified testing and isolation of cases, identification of both asymptomatic and symptomatic individuals and additional care of those with co-morbidities and risk behaviours will all be collectively important for disease containment in India. Reasons for differentials in testing between men and women remain an important area for in-depth study. The increased deployment of vaccines is likely to impact the trajectory of COVID-19 in the coming time, and therefore our data will serve as a comparative resource as India experiences the second wave of infection in light of newer variants that are likely to accelerate disease spread.


Assuntos
Teste de Ácido Nucleico para COVID-19/estatística & dados numéricos , COVID-19/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Comorbidade , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Sexuais , Viagem/estatística & dados numéricos
6.
Trop Doct ; 51(4): 659-660, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33823700

RESUMO

Systemic lupus erythematosus is an autoimmune connective tissue disorder that has well established cutaneous features and typically affects women. However, isolated bilateral periorbital involvement is a rare clinical presentation of systemic lupus erythematosus, which may often delay the diagnosis and treatment. We report such a case in a 20-year-old male.


Assuntos
Lúpus Eritematoso Sistêmico , Adulto , Edema/diagnóstico , Edema/etiologia , Feminino , Humanos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/diagnóstico , Masculino , Pele , Adulto Jovem
7.
Br J Nutr ; 121(12): 1389-1397, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31006420

RESUMO

India has the second largest number of people with type 2 diabetes (T2D) globally. Epidemiological evidence indicates that consumption of white rice is positively associated with T2D risk, while intake of brown rice is inversely associated. Thus, we explored the effect of substituting brown rice for white rice on T2D risk factors among adults in urban South India. A total of 166 overweight (BMI ≥ 23 kg/m2) adults aged 25-65 years were enrolled in a randomised cross-over trial in Chennai, India. Interventions were a parboiled brown rice or white rice regimen providing two ad libitum meals/d, 6 d/week for 3 months with a 2-week washout period. Primary outcomes were blood glucose, insulin, glycosylated Hb (HbA1c), insulin resistance (homeostasis model assessment of insulin resistance) and lipids. High-sensitivity C-reactive protein (hs-CRP) was a secondary outcome. We did not observe significant between-group differences for primary outcomes among all participants. However, a significant reduction in HbA1c was observed in the brown rice group among participants with the metabolic syndrome (-0·18 (se 0·08) %) relative to those without the metabolic syndrome (0·05 (se 0·05) %) (P-for-heterogeneity = 0·02). Improvements in HbA1c, total and LDL-cholesterol were observed in the brown rice group among participants with a BMI ≥ 25 kg/m2 compared with those with a BMI < 25 kg/m2 (P-for-heterogeneity < 0·05). We observed a smaller increase in hs-CRP in the brown (0·03 (sd 2·12) mg/l) compared with white rice group (0·63 (sd 2·35) mg/l) (P = 0·04). In conclusion, substituting brown rice for white rice showed a potential benefit on HbA1c among participants with the metabolic syndrome and an elevated BMI. A small benefit on inflammation was also observed.


Assuntos
Diabetes Mellitus Tipo 2/etiologia , Dieta/métodos , Síndrome Metabólica/complicações , Oryza/efeitos adversos , Sobrepeso/complicações , Adulto , Idoso , Glicemia/análise , Índice de Massa Corporal , Proteína C-Reativa/análise , Estudos Cross-Over , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Hemoglobinas Glicadas/análise , Humanos , Índia/epidemiologia , Insulina/sangue , Resistência à Insulina , Masculino , Síndrome Metabólica/sangue , Pessoa de Meia-Idade , Sobrepeso/sangue , Fatores de Risco , Adulto Jovem
8.
Indian J Tuberc ; 65(2): 118-123, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29579424

RESUMO

BACKGROUND: Cycloserine (CYC) is a second line antitubercular drug that is used for the treatment of multidrug resistant tuberculosis (MDR-TB) along with other antitubercular agents and is often used in developing countries. Monitoring CYC levels in plasma could be useful in the clinical management of patients with MDR-TB. A high performance liquid chromatography method for the determination of CYC in human plasma was developed. METHODS: The method involved extraction of the sample using solid phase extraction cartridges and analysis of the extracted sample using a reverse phase T3 column (150mm) and detection at 240nm with Photo Diode Array (PDA) detector. The chromatogram was run for 15min at a flow rate of 0.4ml/min at 30°C. RESULTS AND CONCLUSION: The assay was specific for CYC and linear from 5.0 to 50.0µg/ml. The relative standard deviations of within- and between-day assays were less than 10%. Recovery of CYC ranged from 102% to 109%. The interference of other second line anti-TB drugs in the assay of CYC was ruled out. The assay spans the concentration range of clinical interest. The specificity and sensitivity of this assay makes it highly suitable for pharmacokinetic studies.


Assuntos
Antituberculosos/uso terapêutico , Cromatografia Líquida de Alta Pressão , Ciclosserina/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Pulmonar/tratamento farmacológico , Antituberculosos/sangue , Ciclosserina/sangue , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tuberculose Resistente a Múltiplos Medicamentos/sangue , Tuberculose Pulmonar/sangue
9.
RSC Adv ; 8(10): 5350-5361, 2018 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35542426

RESUMO

ZnO nanorods were capped with a simple amino acid, viz., l-alanine to increase the carrier concentration and improve the performance of ZnO/CuI heterojunction diodes. The effect of l-alanine capping on the morphology, structural, optical, electrochemical and electrical properties of ZnO nanorods had been studied in detail. The stable structure with two equally strong Zn-O coordinate bonds predicted by density functional theory was in agreement with the experimental results of FTIR spectroscopy. Due to the presence of electron-releasing (+I effect) moieties in l-Alanine, the carrier concentration of capped ZnO nanorods was two orders of magnitude higher and the ZnO/CuI heterojunction device showed more than a two-fold increase in the photovoltaic power conversion efficiency.

10.
Indian J Med Res ; 148(5): 531-538, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30666980

RESUMO

Dietary carbohydrates form the major source of energy in Asian diets. The carbohydrate quantity and quality play a vital function in the prevention and management of diabetes. High glycaemic index foods elicit higher glycaemic and insulinaemic responses and promote insulin resistance and type 2 diabetes (T2D) through beta-cell exhaustion. This article reviews the evidence associating dietary carbohydrates to the prevalence and incidence of T2D and metabolic syndrome (MS) in control of diabetes and their role in the complications of diabetes. Cross-sectional and longitudinal studies show that higher carbohydrate diets are linked to higher prevalence and incidence of T2D. However, the association seems to be stronger in Asian-Indians consuming diets high in carbohydrates and more marked on a background of obesity. There is also evidence for high carbohydrate diets and risk for MS and cardiovascular disease (CVD). However, the quality of carbohydrates is also equally important. Complex carbohydrates such as brown rice, whole wheat bread, legumes, pulses and green leafy vegetables are good carbs. Conversely, highly polished rice or refined wheat, sugar, glucose, highly processed foods such as cookies and pastries, fruit juice and sweetened beverages and fried potatoes or French fries are obviously 'bad' carbs. Ultimately, it is all a matter of balance and moderation in diet. For Indians who currently consume about 65-75 per cent of calories from carbohydrates, reducing this to 50-55 per cent and adding enough protein (20-25%) especially from vegetable sources and the rest from fat (20-30%) by including monounsaturated fats (e.g. groundnut or mustard oil, nuts and seeds) along with a plenty of green leafy vegetables, would be the best diet prescription for the prevention and management of non-communicable diseases such as T2D and CVD.


Assuntos
Diabetes Mellitus Tipo 2 , Carboidratos da Dieta/metabolismo , Síndrome Metabólica , Povo Asiático , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/metabolismo , Dietoterapia/métodos , Ingestão de Energia , Comportamento Alimentar/etnologia , Humanos , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/prevenção & controle
11.
Indian J Med Res ; 145(1): 118-123, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28574024

RESUMO

BACKGROUND & OBJECTIVES: Variations in the N-acetyltransferase (NAT2) gene among different populations could affect the metabolism and disposition of isoniazid (INH). This study was performed to genotype NAT2 gene polymorphisms in tuberculosis (TB) patients from Chennai, India, and compare plasma INH concentrations among the different genotypes. METHODS: Adult patients with TB treated in the Revised National TB Control Programme (RNTCP) in Chennai, Tamil Nadu, were genotyped for NAT2 gene polymorphism, and two-hour post-dosing INH concentrations were compared between the different genotypes. Plasma INH was determined by high-performance liquid chromatography. Genotyping of the NAT2 gene polymorphism was performed by real-time polymerase chain reaction method. RESULTS: Among the 326 patients genotyped, there were 189 (58%), 114 (35%) and 23 (7%) slow, intermediate and fast acetylators, respectively. The median two-hour INH concentrations in slow, intermediate and fast acetylators were 10.2, 8.1 and 4.1 µg/ml, respectively. The differences in INH concentrations among the three genotypes were significant (P<0.001). INTERPRETATION & CONCLUSIONS: Genotyping of TB patients from south India for NAT2 gene polymorphism revealed that 58 per cent of the study population comprised slow acetylators. Two-hour INH concentrations differed significantly among the three genotypes.


Assuntos
Arilamina N-Acetiltransferase/genética , Inativação Metabólica/genética , Isoniazida/sangue , Tuberculose/sangue , Adulto , Feminino , Genótipo , Humanos , Isoniazida/uso terapêutico , Masculino , Pessoa de Meia-Idade , Tuberculose/tratamento farmacológico , Tuberculose/genética , Tuberculose/patologia
12.
Indian Dermatol Online J ; 8(1): 29-31, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28217468

RESUMO

Phaeohyphomycosis is a rare mycotic infection caused by various heterogenous groups of phaeoid (dematiaceous) fungi involving the skin and subcutaneous tissue. Common clinical manifestations are subcutaneous abscesses or cystic swellings. Here, we report a case of subcutaneous phaeohyphomycosis presenting as multiple asymptomatic cystic swellings over the hands and feet without any predisposing factors. Histopathology showed granulomatous inflammation and special stain with Grocott's methanamine silver stain revealed broad pigmented hyphae. Culture showed black-colored colonies identified as Exophiala jeanselmi. The patient was treated with surgical excision of the lesions.

13.
Nutr Metab (Lond) ; 14: 8, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28115978

RESUMO

BACKGROUND: Single nucleotide polymorphisms (SNPs) in lipoprotein lipase gene (LPL) have been shown to influence metabolism related to lipid phenotypes. Dietary factors have been shown to modify the association between LPL SNPs and lipids; however, to date, there are no studies in South Asians. Hence, we tested for the association of four common LPL SNPs with plasma lipids and examined the interactions between the SNPs and dietary factors on lipids in 1,845 Asian Indians. METHODS: The analysis was performed in 788 Type 2 diabetes cases and 1,057 controls randomly chosen from the cross-sectional Chennai Urban Rural Epidemiological Study. Serum triacylglycerol (TAG), serum total cholesterol, and high-density lipoprotein cholesterol (HDL-C) were measured using a Hitachi-912 autoanalyzer (Roche Diagnostics GmbH, Mannheim, Germany). Dietary intake was assessed using a semi-quantitative food frequency questionnaire. The SNPs (rs1121923, rs328, rs4922115 and rs285) were genotyped by polymerase chain reaction followed by restriction enzyme digestion and 20% of samples were sequenced to validate the genotypes obtained. Statistical Package for Social Sciences for Windows version 22.0 (SPSS, Chicago, IL) was used for statistical analysis. RESULTS: After correction for multiple testing and adjusting for potential confounders, SNPs rs328 and rs285 showed association with HDL-C (P = 0.0004) and serum TAG (P = 1×10-5), respectively. The interaction between SNP rs1121923 and fat intake (energy %) on HDL-C (P = 0.003) was also significant, where, among those who consumed a high fat diet (28.4 ± 2.5%), the T allele carriers (TT + XT) had significantly higher HDL-C concentrations (P = 0.0002) and 30% reduced risk of low HDL-C levels compared to the CC homozygotes. None of the interactions on other lipid traits were statistically significant. CONCLUSION: Our findings suggest that individuals carrying T allele of the SNP rs1121923 have increased HDL-C levels when consuming a high fat diet compared to CC homozygotes. Our finding warrants confirmation in prospective studies and randomized controlled trials.

14.
Eur J Clin Pharmacol ; 73(1): 65-70, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27651240

RESUMO

PURPOSE: The aim of the study was to compare plasma concentrations of rifampicin (RMP), isoniazid (INH) and pyrazinamide (PZA) between tuberculosis (TB) patients with and without diabetes mellitus (DM). METHODS: Two-hour post-dosing concentrations of RMP, INH and PZA were determined in adult TB patients that were studied with (n = 452) and without DM (n = 1460), treated with a thrice-weekly regimen in India. Drug concentrations were estimated by HPLC. RESULTS: The median (IQR) INH [6.6 (3.9-10.0) and 7.8 (4.6-11.3)] and PZA [31.0 (22.3-38.0) and 34.1 (24.6-42.7)] microgram per milliliter concentrations were significantly lower in diabetic than non-diabetic TB patients (p < 0.001 for both drugs). Blood glucose was negatively correlated with plasma INH (r = -0.09, p < 0.001) and PZA (r = -0.092, p < 0.001). Multiple linear regression analysis showed RMP, INH and PZA concentrations were influenced by age and drug doses, INH and PZA by DM, RMP by alcohol use and PZA by gender and category of ATT. DM reduced INH and PZA concentrations by 0.8 and 3.0 µg/ml, respectively. CONCLUSIONS: TB patients with DM had lower INH and PZA concentrations. Negative correlation between blood glucose and drug concentrations suggests delayed absorption/faster elimination of INH and PZA in the presence of elevated glucose.


Assuntos
Antituberculosos/sangue , Diabetes Mellitus/sangue , Isoniazida/sangue , Pirazinamida/sangue , Rifampina/sangue , Tuberculose/sangue , Adulto , Antituberculosos/administração & dosagem , Antituberculosos/farmacocinética , Antituberculosos/uso terapêutico , Diabetes Mellitus/tratamento farmacológico , Feminino , Humanos , Isoniazida/administração & dosagem , Isoniazida/farmacocinética , Isoniazida/uso terapêutico , Masculino , Pessoa de Meia-Idade , Pirazinamida/administração & dosagem , Pirazinamida/farmacocinética , Pirazinamida/uso terapêutico , Rifampina/administração & dosagem , Rifampina/farmacocinética , Rifampina/uso terapêutico , Tuberculose/tratamento farmacológico
15.
Chemosphere ; 167: 396-405, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27744197

RESUMO

The paper reports the use of atmospheric non-thermal plasma torch as a catalyst for degradation of various organic pollutants dissolved in water. A flow of He mixed with air was used to produce the dielectric barrier discharge (DBD), at the tip of the torch, using pulsed electric excitation at 12 kV. The torch, operated at a power of 750 mW/mm2, was seen to completely degrade the aqueous solutions of the pollutants namely methylene blue (MB), methyl orange (MO) and rhodamine-B (RB), at around 10-4 M concentrations, the concentration of polluants is one order higher than of routinely used heterogeneous photocatalytic reactions, within 10 min of irradiation time at room temperature. UV Visible spectra of the organic dye molecules, monitored after different intervals of plasma-irradiation, ranging between 1 and 10 min, have been used as tools to quantify their sequential degradation. Further, instead of using He, only air was used to form plasma plume and used for degradation of organic dye which follow similar trend as that of He plasma. Further, Liquid Chromatography Mass Spectroscopy (LCMS) technique has been used to understand degradation pathway of methylene blue (MB) as a representative case. Total organic carbon (TOC) measurements indicates significant decrease in its content as a function of duration of plasma exposure onto methylene blue as a representative case. Toxicity studies were carried out onto Gram negative Escherichia coli. This indicated that methylene blue, without plasma treatment, shows growth inhibition, whereas with plasma treatment no inhibition was observed.


Assuntos
Corantes/química , Águas Residuárias/química , Poluentes Químicos da Água/química , Compostos Azo/química , Catálise , Eletricidade , Hélio , Azul de Metileno/química , Processos Fotoquímicos , Rodaminas/química , Água/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos
16.
Int J Tuberc Lung Dis ; 20(9): 1231-5, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27510251

RESUMO

OBJECTIVE: To determine the effect of SLCO1B1 gene polymorphisms (rs11045819, rs4149032 and rs4149033) on rifampicin (RMP) concentrations in adult tuberculosis (TB) patients from south India. METHODS: We genotyped adult TB patients for three SLCO1B1 gene polymorphisms-rs11045819, rs4149032 and rs4149033-and compared 2-h post-dosing RMP concentrations of the different genotypes for each of the polymorphisms. Plasma RMP was determined using high-performance liquid chromatography. Genotyping was performed using direct sequencing. RESULTS: Among the 256 study patients, minor allele frequencies were respectively 0.01 (A), 0.46 (C) and 0.07 (A) for rs11045819, rs4149032 and rs4149033 polymorphisms; genotype distributions followed Hardy-Weinberg equilibrium. RMP concentrations did not significantly differ between the different genotypes of the three polymorphisms. CONCLUSION: This is the first study to show that rs11045819, rs4149032 and rs4149033 polymorphisms in the SLCO1B1 gene did not influence RMP concentrations in Indian patients.


Assuntos
Antibióticos Antituberculose/sangue , Transportador 1 de Ânion Orgânico Específico do Fígado/genética , Polimorfismo de Nucleotídeo Único , Rifampina/sangue , População Branca/genética , Adulto , Antibióticos Antituberculose/uso terapêutico , Feminino , Frequência do Gene , Genótipo , Técnicas de Genotipagem , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Rifampina/uso terapêutico , Tuberculose/sangue , Tuberculose/tratamento farmacológico , Tuberculose/genética
17.
Int J Tuberc Lung Dis ; 20(9): 1236-41, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27510252

RESUMO

OBJECTIVE: To study the pharmacokinetics of rifampicin (RMP), isoniazid (INH) and pyrazinamide (PZA) in adult tuberculosis (TB) patients and examine factors that influence drug pharmacokinetics. METHODS: Adult TB patients (n = 101) receiving thrice-weekly anti-tuberculosis treatment in the Revised National TB Control Programme (RNTCP) were studied. The study was conducted at steady state after directly observed drug administration. RMP, INH and PZA concentrations were estimated using high-performance liquid chromatography and NAT2 genotyping by real-time polymerase chain reaction. RESULTS: RMP peak concentration (Cmax) was sub-therapeutic (<8 µg/ml) in 88% of the patients. The Cmax of RMP, INH and PZA at 2 h was observed in respectively 83.2%, 97.0% and 92.1% of the patients. The Cmax and area under the curve from 0 to 8 h (AUC0-8) of PZA was lower in TB patients with diabetes mellitus than in non-diabetics. Significant associations were observed between the Cmax and the AUC0-8 of RMP, INH and PZA with drug doses; RMP with category of treatment; INH with smoking, body mass index and N-acetyl transferase 2 genotype; and PZA with sex and smoking. CONCLUSIONS: Several risk factors for drug concentration variations were identified. Two-hour post-dosing drug concentrations mimicked Cmax. A high proportion of TB patients had RMP Cmax below the expected range, which is a matter of concern.


Assuntos
Antituberculosos/farmacocinética , Isoniazida/farmacocinética , Pirazinamida/farmacocinética , Rifampina/farmacocinética , Tuberculose/tratamento farmacológico , Adulto , Antituberculosos/uso terapêutico , Arilamina N-Acetiltransferase/genética , Feminino , Técnicas de Genotipagem , Humanos , Índia , Isoniazida/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Pirazinamida/uso terapêutico , Rifampina/uso terapêutico , Tamanho da Amostra , Adulto Jovem
18.
J Mol Graph Model ; 68: 140-146, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27442589

RESUMO

Grand Canonical Monte Carlo methods in conjunction with continuum Multiscale simulation to estimate the hydration energies and surface potentials of silver halides as demonstrated elsewhere is employed by incorporating random distribution of molecules, nearest neighbor distances and hydration numbers. The extent of dehydration during each step and the corresponding variation in the hydration numbers are evaluated, assuming the validity of hard spheres. These estimates are then employed to deduce the redox potential of the reaction viz. 2AgX(solution)⇔2Ag(solid)+X2(gas). The dependence of these values on the nature of the halides and solvation characteristics is indicated.


Assuntos
Simulação por Computador , Técnicas Eletroquímicas , Halogênios/química , Método de Monte Carlo , Solventes/química , Água/química , Oxirredução , Solubilidade , Termodinâmica
19.
Pediatr Infect Dis J ; 35(5): 530-4, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26825153

RESUMO

OBJECTIVES: To compare the pharmacokinetics of rifampicin (RMP), isoniazid (INH) and pyrazinamide (PZA) between HIV-infected and HIV-uninfected children with tuberculosis (TB) and correlate it with TB treatment outcome. METHODS: HIV-uninfected (n = 84) and HIV-infected (n = 77) children with TB receiving standard thrice weekly treatment were recruited from 6 hospitals in India. Semi-intensive pharmacokinetic sampling was performed during intensive phase of TB treatment after directly observed administration of drugs. Drug concentrations were measured by high performance liquid chromatography. INH acetylator status was determined, and nutritional assessment was done. Children were followed-up and treatment outcomes noted. RESULTS: Children with HIV and TB had significantly lower RMP peak concentration (Cmax) (2.6 vs. 5.1 µg/mL; P < 0.001) and exposure [area under the time-concentration curve (AUC0-8); 10.4 vs. 23.4 µg/mL h; P < 0.001] than those with TB. Among HIV-infected children, a significantly higher proportion had stunting (77% vs. 29%; P < 0.001) and underweight (73% vs. 38%; P < 0.001) compared with children with TB. Combining both groups, RMP Cmax (P = 0.001; adjusted odds ratio = 1.437; 95% confidence interval: 1.157-1.784) and PZA Cmax (P = 0.027; adjusted odds ratio = 1.041; 95% confidence interval: 1.005-1.079) significantly influenced treatment outcome. CONCLUSIONS: HIV infection was associated with lower Cmax of RMP and INH and AUC0-8 of RMP. Over 90% of children in both groups had subtherapeutic RMP Cmax. Cmax of RMP and PZA significantly influenced TB treatment outcome in children with TB. The findings have important clinical implications and suggest the need to increase anti-TB drug doses in children with HIV and TB.


Assuntos
Antituberculosos/administração & dosagem , Infecções por HIV/complicações , Pirazinamida/administração & dosagem , Rifampina/administração & dosagem , Soro/química , Tuberculose/tratamento farmacológico , Antituberculosos/farmacocinética , Criança , Pré-Escolar , Cromatografia Líquida de Alta Pressão , Feminino , Seguimentos , Hospitais , Humanos , Índia , Lactente , Isoniazida/administração & dosagem , Isoniazida/farmacocinética , Masculino , Pirazinamida/farmacocinética , Rifampina/farmacocinética , Resultado do Tratamento
20.
J Mater Sci Mater Med ; 26(8): 216, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26216552

RESUMO

The paper presents the experimental studies pertaining to the adsorption of bovine serum albumin (BSA) on the nanoparticles of nickel ferrite (NiFe2O4) with a view of correlating the adsorption properties to their microstructure and zeta potentials. Physical properties of two kinds of nickel ferrites, one synthesized by thermal plasma route and the other by chemical co-precipitation method, are compared. Maximum adsorption (231.57 µg/mg) of BSA onto nickel ferrite nanoparticles, at body temperature (37 °C) was observed at pH-value of 5.58 for the thermal plasma synthesized particles showing its higher adsorption capacity than those synthesized by wet chemical means (178.71 µg/mg). Under the same physical conditions the value of zeta potential, obtained for the former, was higher than that of the latter over a wide range of pH values (3.64-9.66). This is attributed to the differences in the specific surface energies of the two kinds of nanoparticles arising from the degree of crystallinity. The paper presents the experimental evidence for the single crystalline nature of the individual nanoparticles, with mean size of 32 nm, for the thermal plasma synthesized particles as evidenced from the high resolution transmission electron microscopy and electron diffraction analysis. The measurements also reveal the poor crystalline morphology in the chemically prepared particles (mean size of 28 nm) although the X-ray diffraction patterns are not much different. The atomic force microscopy images confirm that the surfaces of plasma synthesized nanoparticles possesses higher surface roughness than that of chemically synthesized one. Presence of adsorbed protein was confirmed by vibrational spectroscopy. The Langmuir adsorption model is found to fit into the experimental data better than the Freundlich adsorption model.


Assuntos
Compostos Férricos/química , Nanopartículas de Magnetita/química , Níquel/química , Soroalbumina Bovina/química , Adsorção , Animais , Materiais Biocompatíveis/química , Bovinos , Magnetismo , Nanopartículas de Magnetita/ultraestrutura , Teste de Materiais , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Nanotecnologia , Tamanho da Partícula , Gases em Plasma , Difração de Pó , Soroalbumina Bovina/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
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