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1.
Mar Pollut Bull ; 186: 114488, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36563603

RESUMO

In this novel study, an attempt has been made to prepare porous crosslinked poly(ethylene-co-vinyl acetate) polymer (C-EVA). The porous C-EVA was prepared by grafting of maleic anhydride and cetyl alcohol onto the polymer backbone with addition of NaCl as porogen in the brabender mixture at 120 °C and 80 rpm. This was followed by leaching of NaCl with water extraction to generate a highly porous polymer structure which was evident from its SEM micrographs. The polymer was found to have excellent swelling capacity in various oils and organic solvents and showed good selective absorption capacity. The reusability of the synthesized polymer was studied and it was found that it could be reused for more than 30 absorption desorption cycles without undergoing much change in its absorption capacity. The cross-linked polymeric composite was further characterized by FTIR, TGA, XRD, and SEM.


Assuntos
Cloreto de Sódio , Águas Residuárias , Porosidade , Solventes/química , Óleos/química , Polímeros
2.
Curr Alzheimer Res ; 7(3): 200-6, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20088809

RESUMO

As the mechanisms underlying neuronal development and degeneration become clarified, a number of common effectors and signaling pathways are becoming apparent. Here we describe the identification of Abeta, long considered a pathologic mediator of Alzheimers Disease and Down Syndrome, as similarly over-expressed in the neurodevelopmental disease, Fragile X Syndrome. We also show that mGluR5 inhibitors, currently employed for the treatment of Fragile X, reduce Abeta production in rodent models of Fragile X and AD as well as reduce disease phenotypes including seizures. Thus seemingly disparate neurologic diseases may share a common pathologic instigator and be treatable with a common, currently available class of therapeutics.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/biossíntese , Precursor de Proteína beta-Amiloide/metabolismo , Síndrome do Cromossomo X Frágil/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/genética , Precursor de Proteína beta-Amiloide/genética , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Antagonistas de Aminoácidos Excitatórios/farmacologia , Antagonistas de Aminoácidos Excitatórios/uso terapêutico , Proteína do X Frágil da Deficiência Intelectual/genética , Síndrome do Cromossomo X Frágil/tratamento farmacológico , Síndrome do Cromossomo X Frágil/fisiopatologia , Ácido Glutâmico/metabolismo , Humanos , Fenótipo , Receptor de Glutamato Metabotrópico 5 , Receptores de Glutamato Metabotrópico/antagonistas & inibidores
3.
J Chromatogr A ; 1217(3): 307-11, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20004901

RESUMO

The present paper describes the development and validation of a new reversed-phase liquid chromatography-electrospray ionization tandem mass spectrometric method (RP-HPLC-ESI-MS/MS) for simultaneous determination of pyridine, 2-picoline, 4-picoline and quinoline from mainstream cigarette smoke. Liquid-liquid extraction followed by solid-phase extraction was applied to extract the target analytes from cigarette smoke. Baseline chromatographic separation was achieved by utilizing a Zorbax SB-Aq (4.6x150 mm, 5 microm) column in gradient chromatographic conditions with acetonitrile and ammonium acetate buffer as mobile phases. Popular commercially available Indian brand filtered and non-filtered cigarettes were analyzed using the same method. The identification of each chemical was established by chromatographic retention times, analyte specific fragmentation patterns and relative peak area ratios of two product/precursor ion pairs. The limit of detection of this method ranged from 1.74 to 14.32 ng/cig using an injection volume of 20 microl. The reproducibility of this method is excellent and better standard deviations were obtained compared to literature reported values for these chemicals. RSD value is less than 9% for all analytes.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Picolinas/análise , Piridinas/análise , Quinolinas/análise , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Poluição por Fumaça de Tabaco/análise , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray/métodos
4.
Eur Rev Med Pharmacol Sci ; 13(2): 129-32, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19499848

RESUMO

Oxidative stress is implicated as a major factor for nigral neuronal cell death. Metabolic failure in antioxidant mechanisms could hypothetically facilitate the chemical processes that lead to lipid peroxidation. To elucidate whether elevated lipid peroxidation rates might increase risk of developing Parkinson's disease (PD), the Authors determined plasma levels of malondialdehyde (MDA) in 80 PD patients and 80 controls. There was a significant difference between the plasma MDA levels of PD patients and controls (7.48 +/- 1.55 vs 5.1 +/- 1.26 nmol/ml). Plasma MDA levels were inversely related to the age of the PD patients (r = -0.46; p < 0.01) and age of onset but in the control group, no such correlation was observed between the plasma MDA and age. However, there was no significant correlation between plasma MDA levels and the duration of disease, Hoehn and Yahr stages and the Unified Parkinson's Disease Rating Scale (UPDRS). Thus, the results suggest that high plasma lipid peroxidation rates might contribute as a risk factor for PD in West Bengal.


Assuntos
Peroxidação de Lipídeos , Malondialdeído/sangue , Estresse Oxidativo , Doença de Parkinson/metabolismo , Fatores Etários , Idoso , Estudos de Coortes , Feminino , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Neurônios/patologia , Doença de Parkinson/fisiopatologia , Fatores de Risco , Índice de Gravidade de Doença , Substância Negra/fisiopatologia
5.
J Chromatogr A ; 1216(15): 3059-63, 2009 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-19233372

RESUMO

Aromatic amines are one of the sources of carcinogenicity in cigarette and tobacco smoke. Accurate quantification of these chemicals is needed to assess public health risk. A new validated rapid, sensitive and analyte specific liquid chromatography/electrospray ionization tandem mass spectrometric (LC/MS/MS) method has been developed for the simultaneous determination of six aromatic amines in mainstream cigarette smoke using research reference cigarette 2R4F. Three popular Indian brand cigarettes were also analyzed using the same procedure. The limit of detection of this method ranged from 0.04 to 0.59 ng/cig using an injection volume of 7 microl. The identification of each amine was established by chromatographic retention times, analyte specific fragmentation pattern and relative peak area ratios of two product/precursor ion pairs. The method showed excellent reproducibility and was also rapid, selective and robust for aromatic amine determination from cigarette smoke.


Assuntos
Aminas/análise , Carcinógenos Ambientais/análise , Cromatografia Líquida , Espectrometria de Massas em Tandem , Poluição por Fumaça de Tabaco/análise , Poluentes Atmosféricos/análise , Benzidinas/análise , Calibragem , Estabilidade de Medicamentos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
J Colloid Interface Sci ; 298(1): 111-7, 2006 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-16386268

RESUMO

Weight change behavior of fiber-reinforced polymer composites in humid and thermal environments appears to be a complex phenomena. The state of fiber/matrix interface is believed to influence the nature of diffusion modes. A significant weakening often appears at the interface during the hygrothermal ageing. It effects the moisture uptake kinetics and also the reduction of mechanical properties. The importance of temperature at the time of conditioning plays an important role in environmental degradation of such composite materials. An attempt has been made here to evaluate the deleterious effect of temperature on shear strength of carbon/epoxy and glass/epoxy composites during hygrothermal conditionings. Mechanical tests were conducted at room temperature to assess the effectiveness of the relaxation process in the nullification of environmentally-induced damage in the composites.

7.
Med J Armed Forces India ; 57(1): 66-7, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27365585
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