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1.
J Nanosci Nanotechnol ; 15(4): 2733-41, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26353487

RESUMO

The present work deals with two different CdS nanostructures produced via hydrothermal and solvothermal decompositions of aminocaproic acid (ACA)-mixed Cd-thiourea complex precursor at 175 °C. Both nanostructures were extensively characterized for their structural, morphological and optical properties. The powder X-ray diffraction characterization showed that the two CdS nanostructures present a wurtzite morphology. Scanning electron microscopy and energy-dispersive X-ray characterizations revealed that the hydrothermal decomposition produced well-shaped CdS flowers composed of six dendritic petals, and the solvothermal decomposition produced CdS microspheres with close stoichiometric chemical composition. The UV-vis absorption and photoluminescence spectra of CdS dendritic flowers and microsphere nanostructures showed that both nanostructures present a broad absorption between 200 and 700 nm and exhibit strong green emissions at 576 and 520 nm upon excitations at 290 nm and 260 nm, respectively. The transmission electron microscopy (TEM) and Brunauer-Emmett-Teller (BET) characterizations confirmed that CdS microspheres were mesoporous and were composed of small nanocrystals. A possible growth mechanism in the formation of the CdS nanostructures was proposed based on morphology evolution as a function of the reaction time. Furthermore, the as-synthesized CdS nanostructures were found to exhibit highly efficient photocatalytic activities for the degradation of methyl orange (MeO) and rhodamine B (RhB) dyes.


Assuntos
Ácido Aminocaproico/química , Compostos de Cádmio/química , Nanoestruturas/química , Sulfetos/química , Tioureia/química , Temperatura Alta , Fotólise
2.
Mol Biol Evol ; 27(1): 1-6, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19770222

RESUMO

Animal domestication was a major step forward in human prehistory, contributing to the emergence of more complex societies. At the time of the Neolithic transition, zebu cattle (Bos indicus) were probably the most abundant and important domestic livestock species in Southern Asia. Although archaeological evidence points toward the domestication of zebu cattle within the Indian subcontinent, the exact geographic origins and phylogenetic history of zebu cattle remains uncertain. Here, we report evidence from 844 zebu mitochondrial DNA (mtDNA) sequences surveyed from 19 Asiatic countries comprising 8 regional groups, which identify 2 distinct mitochondrial haplogroups, termed I1 and I2. The marked increase in nucleotide diversity (P < 0.001) for both the I1 and I2 haplogroups within the northern part of the Indian subcontinent is consistent with an origin for all domestic zebu in this area. For haplogroup I1, genetic diversity was highest within the Indus Valley among the three hypothesized domestication centers (Indus Valley, Ganges, and South India). These data support the Indus Valley as the most likely center of origin for the I1 haplogroup and a primary center of zebu domestication. However, for the I2 haplogroup, a complex pattern of diversity is detected, preventing the unambiguous pinpointing of the exact place of origin for this zebu maternal lineage. Our findings are discussed with respect to the archaeological record for zebu domestication within the Indian subcontinent.


Assuntos
Bovinos/genética , Evolução Molecular , Criação de Animais Domésticos/história , Animais , Arqueologia , Ásia , DNA Mitocondrial/genética , Geografia , Haplótipos , História Antiga , Índia , Dados de Sequência Molecular , Análise de Sequência de DNA
3.
J Hum Genet ; 56(11): 765-71, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21900945

RESUMO

The sub-Himalayan Terai and Duars, the important outermost zones comprising the plains of East India, are known as the reservoirs of ethnic diversity. Analysis of the paternal genetic diversity of the populations inhabiting these regions and their genetic relationships with adjacent Himalayan and other Asian populations has not been addressed empirically. In the present investigation, we undertook a Y-chromosome phylogeographic study on 10 populations (n=375) representing four different linguistic groups from the sub-Himalayan Terai and Duars regions of East India. The high-resolution analysis of Y-chromosome haplogroup variations based on 76 binary markers revealed that the sub-Himalayan paternal gene pool is extremely heterogeneous. Three major haplogroups, namely H, O and R, are shared across the four linguistic groups. The Indo-European-speaking castes exhibit more haplogroup diversity than the tribal groups. The findings of the present investigation suggest that the sub-Himalayan gene pools have received predominant Southeast Asian contribution. In addition, the presence of Northeast and South Asian signatures illustrate multiple events of population migrations as well as extensive genetic admixture amongst the linguistic groups.


Assuntos
Cromossomos Humanos Y , Variação Genética , Haplótipos , Alelos , Povo Asiático/genética , Biologia Computacional , Frequência do Gene , Humanos , Índia/etnologia , Filogenia , Filogeografia , População Branca/genética
4.
J Nanosci Nanotechnol ; 9(9): 5578-85, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19928268

RESUMO

Microwave-assisted chemical bath deposition (MACBD) is an emerging technique for quick preparation of nanoscale and nanostructured particles. We report a simple and rapid process for synthesis of nanostructured ZnO particles by MACBD from aqueous solution of tetra ammonium zinc hydroxide. The effect of Zn+2 concentrations (0.025 to 0.2 mole/L), pH (10 to 11) and base on morphology and composition of deposited particles has been studied. Precursor solution (PS) containing 0.12 mole/L Zn+2 at pH approximately 10.3 and NaOH yielded ZnO flowers of sizes 1-2 /tm. The ZnO flowers typically consist of a central round rod surrounded by six tapered petals. Other PSs generated mixture of ZnO flowers and Zn(OH)2 rhombic particles. The results are explained on the basis of thermal decomposition of tetra ammonium zinc complex to ZnO or Zn(OH)2.

5.
Front Mol Biosci ; 2: 19, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25988186

RESUMO

Matrix metalloproteinases (MMPs), a large family of calcium-dependent zinc-containing endopeptidases, are involved in the tissue remodeling and degradation of the extracellular matrix. MMPs are widely distributed in the brain and regulate various processes including microglial activation, inflammation, dopaminergic apoptosis, blood-brain barrier disruption, and modulation of α-synuclein pathology. High expression of MMPs is well documented in various neurological disorders including Parkinson's disease (PD), Alzheimer's disease (AD), Japanese encephalitis (JE), and Glaucoma. Although potentially critical, the role of MMPs in neuronal disorders is under-investigated. The present review summarizes the role of MMPs in neurodegeneration with a particular emphasis on PD, AD, JE, and Glaucoma.

6.
Front Genet ; 4: 155, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23950760

RESUMO

With the gradual development of intelligence, human got curious to know his origin and evolutionary background. Historical statements and anthropological findings were his primary tool for solving the puzzles of his own origin, until came the golden era of molecular markers which took no time to prove it's excellence in unveiling answers to the questions regarding the migration pattern of human across different geographical regions. As a bonus these markers proved very much beneficial in solving criminal offenses and in understanding the etiology of many dreaded diseases and to design their prevention. In this review, we have aimed to throw light on some of the promising molecular markers which are very much in application now-a-days for not only understanding the evolutionary background and ancient migratory routes of humans but also in the field of forensics and human health.

7.
Indian J Psychiatry ; 50(3): 166-70, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19742184

RESUMO

BACKGROUND: Schizophrenia is the paradigmatic illness of psychiatry. The involvement of immunological and immunopathological mechanisms in the etiopathogenesis of schizophrenia has been a matter of research, with recently increasing effort. AIMS: In this study, we investigated the incidence of human leukocyte antigen (HLA) Class I antigens to understand the role of HLA genes in schizophrenia. MATERIALS AND METHODS: India born schizophrenic patients in and around Siliguri who attended outpatient department (OPD) of Department of Psychiatry, North Bengal Medical College and Hospital were considered for the present study. After the longitudinal follow up, 50 patients were enrolled for the study. The same number of age, sex and ethnically matched healthy subjects were considered as control. Low resolution polymerase chain reaction-sequence specific primer method was applied for typing the HLA antigens. STATISTICS: The phenotype frequencies were calculated by direct count. chi(2) test was done to compare the frequency of each antigen among the patients and control group and it was followed by Fisher's exact test. Relative risk was estimated by using Haldane's method. RESULTS: The result showed that some of the HLA antigens are associated with the schizophrenia and significant increase were observed for HLA A*03 antigen along with the significant decrease for HLA A*25, A*31 and HLA B*51. CONCLUSIONS: The study provides the evidence for the possible existence of susceptibility locus for schizophrenia within the HLA region. This preliminary observation may help to understand the etiological basis of this disorder and the study may further strengthen the HLA antigens as the marker for schizophrenia.

8.
Can J Psychiatry ; 51(6): 342-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16786814

RESUMO

OBJECTIVES: Genetic associations between delusional disorder and paranoid schizophrenia are not well understood, although involvement of biological factors has been suspected. We investigated the incidence of human leukocyte antigen (HLA) class I alleles in patients with delusional disorder and paranoid schizophrenia, first, to explore a possible immunogenetic etiology of these paranoid disorders and, second, to determine whether they share similar etiologic mechanisms. METHOD: We employed a nested case-control study design. Psychiatric reference data were available for 38,500 patients attending a hospital-based psychiatric outpatient department between 1998 and 2005. We enrolled 100 patients with delusional disorder and 50 patients with paranoid schizophrenia as the subject cases, using DSM-IV criteria. We considered equivalent numbers of healthy volunteers matched for age and ethnic background as control subjects. All subjects came from an India-born Bengali population. We applied the polymerase chain reaction-based molecular typing method to all patients and healthy subjects. RESULTS: The HLA-A*03 gene is significantly associated with delusional disorder as well as with paranoid schizophrenia. This HLA gene alone or in linkage disequilibrium with other HLA genes or other closely linked non-HLA genes may influence susceptibility to delusional disorder and paranoid schizophrenia. CONCLUSIONS: The study reveals important associations between HLA genes and paranoid disorders. Delusional disorder and paranoid schizophrenia may share similar etiologic mechanisms. This preliminary observation may help our understanding of the genetic basis of these paranoid disorders.


Assuntos
Alelos , Antígenos de Histocompatibilidade Classe I/genética , Esquizofrenia Paranoide/genética , Adulto , Estudos de Casos e Controles , Feminino , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Antígenos HLA-A/genética , Antígeno HLA-A3 , Humanos , Imunogenética , Índia , Desequilíbrio de Ligação/genética , Masculino , Pessoa de Meia-Idade , Valores de Referência , Esquizofrenia Paranoide/diagnóstico , Esquizofrenia Paranoide/imunologia , Esquizofrenia Paranoide/psicologia , Estatística como Assunto
9.
Can J Psychiatry ; 50(5): 269-74, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15968843

RESUMO

OBJECTIVE: The etiology of delusional disorder is imperfectly understood. Involvement of biological factors has long been suspected. We examined the incidence of class I human leukocyte antigens (HLAs) in patients with delusional disorder to understand the role of HLA genes and explore a possible immunogenetic etiology for delusional disorder. METHODS: We used a nested case-control study design. Psychiatric reference data were available for 27 500 patients registered between 1998 and 2003. Initially, we enrolled 150 patients with delusional disorder from the India-born Bengali population, using DSM-IV diagnostic criteria. After longitudinal follow-up, 80 patients were found to have only delusional disorder, while the remaining 70 patients represented different illnesses with paranoid symptoms and were excluded. We performed serological typing on all 150 patients and applied the polymerase chain reaction-based high-resolution molecular typing method to the 80 patients with delusional disorder. Eighty healthy donors of the same ethnic background, matched for age, sex, and other socioeconomic variables, formed the control group. RESULTS: Some of the HLA alleles were associated with delusional disorder, and the gene HLA-A*03 was found to be significantly more frequent. This gene may influence patients' susceptibility to delusional disorder. CONCLUSION: The study reveals important associations between HLA genes and delusional disorder. This preliminary observation may help our understanding of this disorder's genetic basis.


Assuntos
Antígenos HLA-A/genética , Transtornos Psicóticos/etnologia , Transtornos Psicóticos/genética , Adulto , Alelos , Estudos de Casos e Controles , Área Programática de Saúde , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Seguimentos , Antígeno HLA-A3 , Antígenos HLA-B/genética , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Transtornos Psicóticos/diagnóstico , Fatores de Risco
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