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1.
Environ Geochem Health ; 40(2): 609-623, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28695304

RESUMO

The concentration of heavy metals was analyzed each of 20 river water, suspended sediments and bed sediments along the stretch of Swarnamukhi River Basin. River water is not contaminated with heavy metals except Fe and Mn. Contamination factor in sediments shows considerable to very high degree contamination with Cr, Cu, Pb and Zn. The sources of these metals could be residential wastes, sewer outfall, fertilizers, pesticides (M-45 + carbondine) and traffic activities apart from natural weathering of granitic rocks present in the basin area. Principal component analyses indicate the interaction between metals in different media. The comparison of metals (Cu, Pb and Zn) in bed sediments of Swarnamukhi River with the Indian and world averages indicates that the values obtained in the basin are above the Indian averages and far below to the world averages. Average shale values and sediment quality guidelines point toward the enrichment and contamination of Cu, Cr, Pb and Zn to several fold leading to eco-toxicological risks in basin.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Metais Pesados/análise , Rios/química , Poluentes Químicos da Água/análise , Índia , Análise de Componente Principal , Medição de Risco
2.
MethodsX ; 4: 55-62, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28138433

RESUMO

Fourier Transform Infrared Spectroscopy (FTIR) was used to study the variations in organic matters of benthic foraminifera (Ammonia beccarii) from four samples collected from beach environments from brackish environments along Tupilipalem coast (South east coast of India). Common absorption bands were observed as peaks in the range of 3600-3400 cm-1, 3000-2850 cm-1, 1750-1740 cm-1, 1640-1600 cm-1, 1450-1350 cm-1, 885-870 cm-1 and 725-675 cm-1 in all the shells of Ammonia beccarii. The FTIR spectrum of station-1 represents the presence of alkanes (CH3) and alkyl halide (C-F stretching) with absorptions at the range 1385-1255 and 1350-1150 cm-1 were observed and ether (C-O stretching) absorption band was observed at stations 1 and 3 with wavenumber of 1115 cm-1 and 1117 cm-1 respectively. Alkynes C-H bend was observed at station-1 with the wavenumber of 667.43 cm-1. The shifting of peak positions in all the samples is could be due to presence of organic matter in the samples. Satellite remote sensing and field observation data revealed that the river mouth at Tupilipalem coast was closed by a sand bar. Consequentially, this waterbody may affect the species diversity. •Positions of the sampling locations were identified using a hand-held Garmin Global Positioning System (GPS).•Foraminifera from the sediment were obtained using a mixture of Bromoform and Acetone.•The functional groups present in the benthic foraminifera shells were recorded in the spectral range of 4000-400 cm-1 using an FT-IR Spectrophotometer.

3.
Mar Pollut Bull ; 113(1-2): 542-551, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27580872

RESUMO

A total of 112 bottom water and sediment samples collected at fixed stations in pre-monsoon and post-monsoon from four estuaries (Pennar, Uppateru, Swarnamukhi, and Kalangi) showed foraminiferal test abnormalities in heavy metal concentrations (Co, Cr, Cu, Fe, Mn, Ni, and Pb). Low diversity of fauna was due to the predominance of a limited number of opportunistic species capable of achieving high densities in adverse environmental conditions and the reduction in the number of species intolerant of such conditions. In this study, classification of 54 common species according to their distribution is presented. Approximately 15 species showed quite low diversities at stations 23-27 and 44-51. Because of the effect of heavy metal pollution in these estuaries, drastic changes in the number of species and diversity of foraminifera were observed. These changes in foraminiferal species and the increase in test abnormalities are proxies of environmental stress on the estuarine ecosystem.


Assuntos
Estuários , Foraminíferos , Metais Pesados , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Índia
4.
J Mol Neurosci ; 55(2): 355-66, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24880240

RESUMO

The present study evaluates the protective effect of citalopram against cold-restraint stress (CRS) paradigm. Rats were pretreated with citalopram (0.1, 1.0, and 10.0 mg/kg) acutely and repeatedly for 21 days before exposure to the CRS procedure. None of the doses of citalopram attenuated CRS-induced gastric ulcers in the acute study. In contrast, repeated pretreatment of citalopram at a dose level of 0.1 mg/kg attenuated the CRS-induced gastric ulcers. Citalopram (0.1 mg/kg) diminished CRS-induced increase in plasma corticosterone, but not plasma norepinephrine level in the chronic study indicating its effect on hypothalamic-pituitary-adrenal axis function. Repeated citalopram (0.1 mg/kg) pretreatment attenuated CRS-induced changes in serotonin turnover in the hippocampus and amygdala. Moreover, repeated pretreatment with citalopram (0.1 mg/kg) mitigated the CRS-induced increase in the expression of brain-derived neurotrophic factor (BDNF) and nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB) in the hippocampus and amygdala. These results suggest that there is a region- and a dose-specific effect of citalopram on CRS-induced BDNF-NFκB activation. Therefore, citalopram showed antistress activity in the CRS model through changes in the stress-responsive pathways such as hypothalamic-pituitary-adrenal-axis and brain serotonergic system apart from decreasing the expression of BDNF and NFκB.


Assuntos
Linfócitos B/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Citalopram/farmacologia , Resposta ao Choque Frio , NF-kappa B/metabolismo , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Estresse Psicológico/tratamento farmacológico , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/metabolismo , Animais , Linfócitos B/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Citalopram/uso terapêutico , Corticosterona/sangue , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , NF-kappa B/genética , Norepinefrina/sangue , Ratos , Serotonina/sangue , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Estresse Psicológico/complicações , Estresse Psicológico/metabolismo
6.
Environ Monit Assess ; 142(1-3): 319-23, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17985206

RESUMO

A study of benthic foraminiferal species was carried out along Nellore Coast of South India. Analysis of surfacial sediment samples from the study area shows enrichment in heavy metals (Cr, Cu, Pb and Zn). The environment has become so lethal to foraminifera that minimal species number (4-7) can currently preserved in living condition in a depth less than 5-fth contour from coast. Samples from outfalls which receive only agricultural and aquacultural drainage water show heavy metal concentrations slightly higher to natural baseline levels, and yielding, living foraminifera (10-15). The frequent occurrence of deformed and abnormal specimens in Industrial outfalls, comparable to aquacultural and agricultural outlets reveal that (a) benthic foraminifera are more sensitive to industrial wastes containing heavy metals, (b) agricultural and aquacultural wastes do not significantly harm benthic foraminifera, and (c) morphological abnormalities of the foraminiferal tests depend upon the nature of the pollutant.


Assuntos
Eucariotos/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Sedimentos Geológicos/química , Índia , Resíduos Industriais , Metais Pesados/química , Metais Pesados/toxicidade , Oceanos e Mares , Eliminação de Resíduos Líquidos , Água/química , Poluição Química da Água
7.
J Hazard Mater ; 2007 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-17532133

RESUMO

This article has been withdrawn consistent with Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The Publisher apologizes for any inconvenience this may cause.

8.
Artigo em Inglês | MEDLINE | ID: mdl-15911408

RESUMO

Electron paramagnetic resonance (EPR) studies have been carried out on Mn2+ ions doped in zinc malate trihydrate single crystals in the temperature range 123-413 K on X-band frequency. The EPR spectrum at room temperature exhibits a group of five fine structure transitions each splits into six hyperfine components. Angular variation studies reveal that Mn2+ ions enter the lattice substitutionally. From the observed EPR spectrum, the spin-Hamiltonian parameters have been evaluated. The variation of zero-field splitting parameter (D) with temperature is measured. From the optical absorption spectrum, the crystal field splitting parameter Dq and the Racah interelectronic repulsion parameters B and C have been evaluated. The infrared spectrum exhibits bands characteristic of the carboxylic acid salts.


Assuntos
Cátions Bivalentes/química , Malatos/química , Manganês/química , Compostos de Zinco/química , Cristalização , Espectroscopia de Ressonância de Spin Eletrônica , Espectrofotometria Infravermelho , Temperatura
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 59(13): 2955-65, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14583272

RESUMO

Electron Paramagnetic Resonance (EPR), optical and infrared (IR) spectral studies have been performed on the pure and Cu-adsorbed exoskeletons of marine environment. The EPR spectrum of exoskeletons at room temperature exhibits a sharp signal at g approximately 1.9970. The possible redox mechanisms have been noticed on heating these exoskeletons in which the low spin Mn(3+) reduces to Mn(2+). The optical absorption spectra also give the evidence of the presence of Mn(3+) ions. The effects of thermal sintering on the EPR spectra have been studied and discussed in detail. The Cu-adsorbed samples clearly showed the adsorption of the Cu(2+) ions over CaCO(3) and the redox mechanism in these samples have been monitored by EPR.


Assuntos
Carbonato de Cálcio/química , Cobre , Crustáceos/química , Moluscos/química , Animais , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Oxirredução , Água do Mar , Espectrofotometria Infravermelho/métodos
10.
Postgrad Med J ; 79(932): 352-4, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12840128

RESUMO

Rabies encephalitis has a classical clinical presentation and its diagnosis is unmistakable. In about a fifth of cases rabies occurs as its paralytic form, which lacks the classic symptoms and may mimic other diseases, especially acute disseminated encephalomyelitis (ADEM). Magnetic resonance imaging of the brain in rabies shows a distinct abnormal pattern that differentiates it from ADEM. Hence it may be a useful tool in diagnosis of paralytic rabies. Failure to administer post-exposure rabies immunoglobulin along with the rabies vaccine may result in vaccine failure.


Assuntos
Mordeduras e Picadas/complicações , Encefalite Viral/diagnóstico , Raposas , Raiva/diagnóstico , Animais , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Paralisia/virologia
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