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1.
J Phys Condens Matter ; 36(38)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38876090

RESUMO

In this paper, we report a detailed investigation of the crystal structure, magnetic, magnetocaloric, magneto-transport and electrical polarization properties of a new multiferroic material in the polycrystalline and nanocrystalline form of the Dy2MnCoO6double perovskite. Both compounds crystallized in the monoclinic structure with P21/n space group. The magnetic properties of both systems are mainly dominant ferromagnetic (FM) and weak antiferromagnetic (AFM). The FM/AFM coupling is related by the competing and combining functions of the radius and the magnetic moments of rare earth ions (i.e. 3d-4f exchange interactions). The reduction of the saturation magnetization in the isothermal magnetization curves can be explained by the existence of anti-phase boundaries and local anti-site defects in the system. Moreover, these materials hold reasonable values of magnetocaloric parameters and the absence of hysteresis makes the system a potential candidate for magnetic refrigeration. These compounds revealed two magnetic phase transitions, according to the appearance of two peaks in the temperature dependence of magnetic entropy change curves. The temperature dependent resistivity data for both the systems display semiconductor nature near room temperature and insulating like behavior at low temperature regime. The variable-range hopping conduction mechanism is used to best understand their transport mechanism. In addition, the electrical polarization loop at low temperature confirms the presence of ferroelectricity for both the studied systems. The decreases polarization under an external magnetic field evidence the weak magnetoelectric coupling. The coexistence of FM ordering with insulating behavior and ferroelectricity at low temperature promises new opportunities and improvements in next generation applications for information storage, spintronic, and sensors.

2.
Front Genet ; 14: 1256756, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38155717

RESUMO

Lung adenocarcinoma (LUAD), the most prevalent form of non-small cell lung cancer (NSCLC), remains a leading cause of cancer-related death globally, including in India, with a 5-year survival rate below 10%. Despite these grim statistics, recent advances in the use of next-generation sequencing (NGS) for identifying genetic alterations and the emergence of targeted therapies have opened new possibilities for personalized treatment based on distinct molecular signatures. To understand the molecular pattern of NSCLC, a retrospective study was conducted with 53 Indian LUAD patient samples, using a targeted NGS panel of 46 cancer-relevant oncogenes to identify clinically relevant variants. Pathogenic or likely pathogenic variants were detected in 94% of the 53 cases. Non-synonymous mutations, rearrangements, copy number alterations, insertions, and deletions of functional relevance were observed in 31 out of 46 genes. The most frequently mutated genes included TP53 (52.8%) and EGFR (50.9%), followed by RET, PIK3CA and ERBB2; some patients had multiple alterations in the same gene. Gender-based enrichment analysis indicated that ALK and IDH2 alterations were more prevalent in females, while TP53 and PTEN were more common in males. No significant correlation was found between mutations and other clinicopathological attributes, such as age, stage, and subtype. A higher prevalence of EGFR, RET, PIK3CA, ERBB2 and ALK mutations were observed compared to previous LUAD genetic studies coupled with a lower frequency of KRAS mutations. Clinically actionable variants were annotated using OncoKB and categorized into the four therapeutic levels based on their clinical evidence. Seventy-nine percent of cases had at least one clinically actionable alteration. Most patients (39.6%) had the highest level of actionability (Level 1) wherein an FDA-approved drug is available specifically for the observed mutation in lung cancer patients. EGFR Exon19 in-frame deletions and EGFR L858R were the most frequent among targetable variants (20.7%). These findings emphasize the importance of a selective NGS panel in enabling personalized medicine approaches by identifying actionable molecular alterations and informing the choice of targeted therapy for more effective treatment options in Indian NSCLC patients.

3.
J Cancer Res Ther ; 19(Suppl 2): S869-S876, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38384068

RESUMO

BACKGROUND: A multicentric private hospital-based retrospective study was conducted to understand the epidemiology of breast cancer in terms of demographics and clinical characteristics (staging and hormone receptor status) at the time of diagnosis. METHODS: The data for 5,688 female breast cancer patients were collected from the hospital and clinical records of four study centres. All statistical analysis was performed using Microsoft Excel 2016 and R software. Survival was estimated by the Kaplan-Meier method and compared by the log-rank test. A P value of <.05 was considered statistically significant. RESULTS: The mean and median age of the study population was 52.6 (± 12.4) years and 53.0 (range 51-54 across the four centers) years, respectively. About 68% of patients were in the age category of 41 65 years, 17.6% were <40 years old among whom 23.4% of patients reported a positive family history. Most of the patients (66.3%) were diagnosed at an early stage (Stage I and II). The 3-year OS probability was 100%, 97.5%, 94.1%, and 74.7% for TNM Stages I, II, III, and IV, respectively. The 3-year RFS was 95.7%, 95.5%, 84.5%, and 49% for TNM Stages I, II, III, and IV, respectively. CONCLUSION: The present study highlights the epidemiological distribution of breast cancer patients. It emphasizes the importance of disease awareness among the urban and educated female population as most patients were diagnosed at earlier stages and demonstrated higher OS and RFS than reported in government registries.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Pessoa de Meia-Idade , Adulto , Neoplasias da Mama/patologia , Estudos Retrospectivos , Estadiamento de Neoplasias , Sistema de Registros , Índia/epidemiologia , Prognóstico
4.
Phys Chem Chem Phys ; 24(14): 8233-8244, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35319050

RESUMO

The magnetic and magnetocaloric properties of polycrystalline Gd0.5Sr0.5-xCaxMnO3 (x = 0.0, 0.2, 0.3, 0.4 and 0.5) compounds have been investigated. Depending upon the Ca and Sr proportions, fascinating magnetic ground states were observed in the Gd0.5Sr0.5-xCaxMnO3 compounds. Here, the dominating nature of the canted magnetic state (for the Gd0.5Ca0.5MnO3 compound) and glassy (disordered ferromagnetic) magnetic state (for the Gd0.5Sr0.5MnO3 compound) are observed. However, for the intermediate doped samples (x = 0.2, 0.3, 0.4), a competing nature is found in their magnetic and exchange bias properties. Additionally, in the low temperature region, a significantly large magnetocaloric effect is observed for all the samples. At a 70 kOe external magnetic field, the highest observed value of the magnetocaloric entropy change is 21.58 J kg-1 K-1 (for the Gd0.5Ca0.5MnO3 sample) and the lowest is 10.15 J kg-1 K-1 (for the Gd0.5Sr0.5MnO3 sample).

5.
World Allergy Organ J ; 2(1): 9-12, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23282888

RESUMO

BACKGROUND: : Food allergy may be defined as an immunoglobulin E-mediated immune response to food proteins. Such studies have previously not been done in Calcutta, India. The present study was therefore undertaken to record the sensitivity to commonly consumed foods in patients with allergic rhinitis and asthma. MATERIALS AND METHODS: : A survey of 800 patients (410 males and 390 females) reporting to the Allergy Unit of the Institute of Child Health, Calcutta, were selected for the study conducted from May 2006 to April 2007. Respiratory allergic patients in the age group of 5 to 60 years were evaluated using a standard questionnaire, and skin prick test was performed using common food and aeroallergens. RESULTS/CONCLUSIONS: : Out of the 684 patients with a history of food allergy, most of them, that is, 338, are in the age group 16 to 40 years, 192 of them were in the age group 41 to 60 years, and 154 were in the age group 5 to 15 years. Most of the patients with food allergy had asthma (65.05%), rhinitis and asthma (20.03%), and skin allergies (4.97%), such as itching, eczema, and urticaria. The foodstuffs that were found to elicit symptoms of hypersensitivity were egg, milk, wheat, pulses, vegetables, fishes, and fruits.The patients aged between 16 and 40 years (male-female ratio, 1:1.19) were mostly sensitive to prawn, brinjal, banana, ladyfinger, papaya, wheat, and egg. The age group 41 to 60 years (male-female ratio, 1:1.04) had high skin reactivity to brinjal, egg, banana, fish, and Phaseolus mungo. Patients younger than 16 years (male-female ratio, 1:1.33) were sensitized to brinjal, prawn, banana, spinach, and egg. We observed that food hypersensitivity also reflects different genetic factors and variations in cultural and dietary habits of each individual.

6.
J Infect Public Health ; 1(2): 121-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-20701853

RESUMO

A community-based cross-sectional study was conducted in brothel-based sex workers of West Bengal, Eastern India, to determine their oncogenic human papillomavirus (HPV) status and the presence of pre-cancerous lesions. A total of 229 sex workers from three districts of West Bengal participated in the study. All the study participants were interviewed with the aid of a pre-tested questionnaire to determine their sociodemographics, risk behaviour and risk perceptions after obtaining informed verbal consent. The interview was followed by collection of cervical cells from all participants using a disposable vaginal speculum and cervical cytobrush. Oncogenic HPV DNA was detected by real-time polymerase chain reaction (PCR). A simultaneous Papanicolaou test ('Pap smear') was performed to detect cervical cytological abnormalities. Overall, the prevalence of oncogenic HPV was found to be 25% (58/229) among the studied population. A subset (n=112) of the sample was tested separately to determine the existence and magnitude of HPV genotypes 16 and 18. The results showed that genotype 16 was prevalent in 10% (11/112), genotype 18 in 7% (8/112) and both genotype 16 and 18 in 7% (8/112). The HPV prevalence rate showed a decreasing trend with age, being 71.4% in the 10-19 years age group, 32.3% in the 20-29 years age group, 18.3% in the 30-39 years age group and 2.5% in the >or=40 years age group (statistically significant differences, P1 year, respectively. This difference was found to be statistically significant both by univariate and multivariate analysis. In this study, it was observed that sex workers with an average number of daily clients of six or more had an HPV prevalence of 67% (n=6), those with four to five clients had a prevalence of 45% (n=9), those with two to three clients had a prevalence of 30% (n=34) and those with one or less clients had a prevalence of 10% (n=9) (statistically significant differences, P=0.00003). Multivariate analysis showed a statistical association only with a duration of sex work of or=101 (OR=2.5; 95% CI 1.3-5). Regarding pre-cancerous lesions, 2 of 229 sex workers showed the presence of a low-grade squamous intraepithelial lesion along with high-risk HPV. Thus, 1% of the studied population suffer from a pre-cancerous lesion caused by high-risk HPV. This study concludes that young sex workers are particularly vulnerable to high-risk HPV, similar to human immunodeficiency virus (HIV). The observation of older sex workers relatively free from HPV supports the view of acquired immunity against HPV, which needs to be studied in-depth further. There is a need for a suitable community-based intervention programme targeted towards sex workers, with special reference to younger sex workers, for control and prevention of HPV and cervical cancer. Vaccination against HPV for newly entrant sex workers may be an important component for a successful intervention programme.


Assuntos
Infecções por Papillomavirus/epidemiologia , Lesões Pré-Cancerosas/virologia , Trabalho Sexual , Doenças Virais Sexualmente Transmissíveis/epidemiologia , Neoplasias do Colo do Útero/virologia , Adolescente , Adulto , Colo do Útero/patologia , Colo do Útero/virologia , Criança , Estudos Transversais , Feminino , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 18/isolamento & purificação , Humanos , Índia/epidemiologia , Entrevistas como Assunto , Análise Multivariada , Oncogenes , Teste de Papanicolaou , Infecções por Papillomavirus/virologia , Reação em Cadeia da Polimerase , Lesões Pré-Cancerosas/epidemiologia , Sondas RNA , Fatores de Risco , Fatores de Tempo , Neoplasias do Colo do Útero/epidemiologia , Esfregaço Vaginal , Adulto Jovem
7.
Ann Agric Environ Med ; 11(1): 45-52, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15236497

RESUMO

A continuous 2-year volumetric aerobiological survey was conducted in Berhampore town, a centrally located and representative part of West Bengal, India. The aim of the study was to assess the allergising potential of airborne pollen grains of West Bengal. A total of 31 pollen types were identified of which Poaceae (grasses) pollen showed maximum frequency, followed by Cyperaceae, Cassia sp., Acacia auriculiformis, etc. The seasonal periodicities of the pollen types and their relationship to meteorological conditions were investigated. It was found that the pollen concentration is positively correlated with temperature and negatively correlated with rainfall and relative humidity. Clinical investigations by skin prick test were carried out to detect allergenicity of pollen types. Eighteen common airborne pollen types induced positive responses of which pollen extracts of Saccharum officinarum (grass), Azadirachta indica, Cocos nucifera, Phoenix sylvestris, Cyperus rotundus and Eucalyptus citriodora showed strongest sensitising potential. This result is consistent with previous investigations in different parts of West Bengal.


Assuntos
Poluentes Atmosféricos/imunologia , Alérgenos/imunologia , Grão Comestível , Monitoramento Ambiental , Pólen/imunologia , Hipersensibilidade Respiratória/imunologia , Poluentes Atmosféricos/efeitos adversos , Alérgenos/efeitos adversos , Reações Cruzadas , Monitoramento Ambiental/métodos , Humanos , Índia , Conceitos Meteorológicos , Pólen/efeitos adversos , Fatores de Risco , Estações do Ano , Testes Cutâneos , Temperatura , Fatores de Tempo , População Urbana
8.
Virology ; 292(1): 35-43, 2002 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-11878906

RESUMO

Human hepatitis B virus (HBV) variants containing in-frame core internal deletion (CID) have been demonstrated to contain all the functional features of defective interfering (DI) particles (Yuan, T. T.-T., M.-H. Lin, D. S. Chen, and C. Shih, 1998, J. Virol. 72, 578-584). Here, we report that out-of-frame HBV CID variants exhibit defective interfering property similar to in-frame CID variants characterized previously. This result raises the possibility that it may be the deleted pregenomic RNA product, rather than the deleted core protein product, that is responsible for interference. Furthermore, a genomic deletion elsewhere does not cause interference since preS2 deletion variants exhibit no influence on wild-type HBV replication. Consistent with the natural occurrence of HBV CID variants, we recently identified CID variants of woodchuck hepatitis virus (WHV) in natural infection. However, unlike HBV CID variants, functional characterization of WHV CID variants using a human hepatoma cell line has not revealed any interference in tissue culture. In summary, defective interference is a general phenomenon for both in-frame and out-of-frame HBV CID variants.


Assuntos
Deleção de Genes , Variação Genética , Antígenos do Núcleo do Vírus da Hepatite B/genética , Vírus da Hepatite B da Marmota/genética , Vírus da Hepatite B/genética , Animais , Sequência de Bases , Vírus Defeituosos , Teste de Complementação Genética , Hepatite B/veterinária , Hepatite B/virologia , Vírus da Hepatite B da Marmota/fisiologia , Vírus da Hepatite B/fisiologia , Humanos , Marmota , Dados de Sequência Molecular , Análise de Sequência de DNA , Células Tumorais Cultivadas
9.
Microbiology (Reading) ; 141 ( Pt 8): 1977-1983, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7551060

RESUMO

PFGE analysis of the NotI- and SfiI-digested genome of Vibrio cholerae O139 strains isolated from different epidemic regions of India showed that all the strains are of clonal origin and the genome size is about 2.2 Mb. An analysis of the electrophoretic profiles of the genome of O139 strains, the RFLP of the cholera toxin (ctx) gene and Southern blot hybridization of NotI-digested genomes of classical, El Tor and O139 with a NotI-linking clone of classical strain 569B, suggest that these strains closely resemble V. cholerae O1 biotype El Tor, but are widely different from the classical O1 vibrios. Using restriction enzymes which cleave a single site in either the core region or in the direct repeat sequence (RS) of the CTX genetic element, it has been shown that the genome of most of the O139 strains has two copies of the ctx gene in tandem connected by two RSs. The chromosomal location of the CTX genetic element in the O139 strain is the same as that reported for El Tor vibrios. The organization of the virulence gene cassettes in different O139 strains shows genetic heterogeneity in the population. Whilst most of the epidemic strains have two copies of the CTX genetic element, in some strains the number of elements has been amplified and in at least one strain a single copy of the element has been deleted.


Assuntos
Toxina da Cólera/genética , DNA Bacteriano/análise , Dosagem de Genes , Genoma Bacteriano , Vibrio cholerae/genética , Southern Blotting , Desoxirribonucleases de Sítio Específico do Tipo II , Eletroforese em Gel de Ágar , Eletroforese em Gel de Campo Pulsado , Polimorfismo de Fragmento de Restrição , Sequências Repetitivas de Ácido Nucleico , Mapeamento por Restrição
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