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2.
Sci Bull (Beijing) ; 69(11): 1647-1652, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38644131

RESUMO

We report the charge-changing cross sections (σcc) of 24 p-shell nuclides on both hydrogen and carbon at about 900A MeV, of which 8,9Li, 10-12Be, 10,14,15B, 14,15,17-22N and 16O on hydrogen and 8,9Li on carbon are for the first time. Benefiting from the data set, we found a new and robust relationship between the scaling factor of the Glauber model calculations and the separation energies of the nuclei of interest on both targets. This allows us to deduce proton radii (Rp) for the first time from the cross sections on hydrogen. Nearly identical Rp values are deduced from both target data for the neutron-rich carbon isotopes; however, the Rp from the hydrogen target is systematically smaller in the neutron-rich nitrogen isotopes. This calls for further experimental and theoretical investigations.

3.
Arch Med Res ; 54(5): 102852, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37438214

RESUMO

BACKGROUND AND OBJECTIVES: Overexpression of the EZH2 gene silences several genes involved in DNA repair, cell-cell adhesion, and tumor suppressor genes, resulting in the development of several types of cancers. In the present study, a genetic polymorphism analysis was performed by selecting three SNPs (rs.2302427C>G, rs.3757441C>T, and rs.6950683T>C) of the EZH2 gene based on our previous in silico studies. METHODS: A total of 250 breast cancer patients and 250 healthy individuals were recruited for the study. Patients with pre-operative breast cancer with different clinical-pathological variables and age-matched healthy women were recruited for the EZH2 gene expression analysis. RESULTS: The genetic polymorphism analysis revealed two SNPs (rs.2302427C>G and rs.6950683T>C) of the three studied SNPs of the EZH2 gene have a protective role in all three genetic models. The haplotype analysis predicted that two haplotypes ACGT and ACGC were significantly associated with a lower risk of breast cancer. INTERPRETATION AND CONCLUSIONS: Three significant findings of the SNP rs.2302427C>G (Asp193His) i.e., protective role against breast cancer, survival advantage in ER+/tamoxifen treated breast cancer patients, and decreased expression due to the presence of mutant GG genotype, suggests considering it as an important prognostic biomarker for a good survival outcome of breast cancer patients treated with ER+/tamoxifen. Compared with other studies, the other SNP rs.3757441T>C was observed to have a protective effect in breast cancer biology but plays an antagonistic role in colorectal cancer (CRC) biology. To our knowledge, this is the first detailed study on computationally validated EZH2 SNPs in breast cancer.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Prognóstico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Tamoxifeno , Complexo Repressor Polycomb 2/genética , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Biomarcadores
4.
J Biomol Struct Dyn ; 40(19): 9389-9402, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34060427

RESUMO

Polymorphisms in the CYP2C19 have a huge impact on drug processing, out of which CYP2C19*2 and CYP2C19*3 are the most common variants associated with reduced metabolism of drugs. Mechanism by which two variants contribute in poor metabolization of drugs and cancer is not well understood. Here, we hypothesized that the mutations in CYP2C19 gene might affect the risk of chronic myeloid leukemia patients (CML). Present study has two main objectives: first to investigate the allele frequencies of CYP2C19*2 and CYP2C19*3 associated gene polymorphisms in CML patients and to elucidate the structural stability, conformation and functions of protein encoded by such variants. Genotyping of CYP2C19 was performed in 103 CML patients and 103 matched healthy controls. Heterozygous genotype of CYP2C19*2 was higher in CML patients (13.59%) than the controls (4.85%). Whereas, CYP2C19*3 allele frequency was not observed in cases as well as in controls. Furthermore, molecular dynamics (MD) simulation was applied to monitor the structural and conformational effect of above mutants. MD simulation results demonstrated that these mutants formed unstable proteins with distorted conformations, altered residues network and affected drug binding site which led to malfunction of mutant proteins. Hence, the study provides the role of CYP2C19 gene polymorphisms in susceptibility to CML population and explored the molecular basis of malignancies caused which may aid in the development of precise medicine or adjusting the drug dosages so as to reduce the chemotherapeutic side effects.Communicated by Ramaswamy H. Sarma.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Polimorfismo Genético , Humanos , Citocromo P-450 CYP2C19/genética , Frequência do Gene , Genótipo , Alelos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética
5.
J Genet ; 1002021.
Artigo em Inglês | MEDLINE | ID: mdl-34825659

RESUMO

EZH2 is a classic histone methyltransferase that causes the trimethylation of H3K27 and consequently suppresses the cancer preventive genes. The role of elevated levels of EZH2 expression in breast cancer aggressiveness and poor prognosis is very well established. The present study focusses on the insight of the clinically important SNPs of EZH2 gene in determining the structure-function relationship towards breast cancer susceptibility. For this purpose the EZH2 SNPs (rs41277434A>C and rs201135441C>T (A490T)) were computationally explored and further the prediction outcomes were validated by performing population-based association and pharmacogenetic study in north Indian region of Punjab. The results of the present analysis provided the novel insight of rs201135441C>T (A490T) mutation, that A>T change i.e. nonpolar amino acid to polar amino acid stabilizes the enzyme-substrate (EZH2-Histone) complex which in turn promotes trimethylation over histone 3 (H3) at lysine residue 27 (H3K27me3) and this might be leading to the methylation of the promoter region of various cancer preventive genes, hence may increase the risk of breast cancer susceptibility. Further the association based study of SNP rs201135441C>T (A490T) support the in silico outcomes by revealing that the T mutant allele of rs201135441 has significantly increased the risk of breast cancer susceptibility and also reduce the overall survival and progression free survival of ER+/tamoxifen treated breast cancer patients and triple negative breast cancer (TNBC) patients, respectively. To the best of our knowledge, this is the first study on EZH2 polymorphism with breast cancer. In conclusion, these findings suggest that these variations in the EZH2 gene may have strong clinical significance as they can be targeted for prognosis, prevention and in drug development.


Assuntos
Neoplasias da Mama/genética , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Polimorfismo de Nucleotídeo Único , Tamoxifeno/uso terapêutico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/mortalidade , Progressão da Doença , Epigênese Genética , Humanos , Prognóstico , Análise de Sobrevida , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/mortalidade
6.
J Cancer Res Ther ; 17(2): 311-326, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33063698

RESUMO

Polycomb group proteins (PcG) are multi-subunit structure, consisting of polycomb repressive complex 1 (PRC1), PRC2/3, and pleiohomeotic repressive complex. PRC1 is made up of PHC, BMI-1, CBX, and Ring 1A/B. PRC2 protein complex included embryonic ectoderm development, PCL, SUZ12, SET domain, enhancer of zeste homolog-2 protein (EZH2), and Nurf55. The third subunit PhoRC consists of Pho and DSFMBT subunits. One of the important subunits of PcG group of protein is EZH2 (a histone methyltransferase), which catalyzes tri-methylation of histone H3 at Lys 27 (H3K27me3) to regulate gene expression through epigenetic machinery and induces silencing of specific gene transcription. In case of breast cancer and prostate cancer, EZH2 is very well studied. Evidence shows that EZH2 is overexpressed and mutated in a variety of human cancers, rendering EZH2 an attractive target for the design of new chemotherapeutic drugs in cancer. EZH2 also functions both as a transcriptional suppressor and a transcriptional co-activator, depending on H3K27me3 or its absence. In this review, we summarized various studies reported till date, elucidating the structure of PRC2 complex, various mechanisms involved with this, and highlighting the role of EZH2 in breast cancer and prostate cancer progression. An increased understanding of the mechanisms that underlie the pathogenesis of wide spectrum of cancers is therefore needed to develop novel therapeutic approaches for this disease and to improve the quality of life in patients.


Assuntos
Neoplasias da Mama/genética , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Neoplasias da Próstata/genética , Mama/patologia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Progressão da Doença , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Feminino , Humanos , Masculino , Mutação , Próstata/patologia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia
7.
Toxicol Rep ; 6: 505-513, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31211096

RESUMO

The present study has been investigated the role of gallic acid (GA) in paclitaxel-induced neuropathic pain. The neuropathic pain was developed with paclitaxel (PT: 2 mg/kg, i.p.) administration in mice. GA (20 and 40 mg/kg) and pregabalin (PreG: 5 mg/kg) were administered intravenously for 10 consecutive days. The neuralgic sensations were investigated by assessing various pain tests like acetone drop, pinprick, plantar, tail flick, and tail pinch test. Mice pain behaviors were evaluated on 0, 4th, 8th, 12th and 16th days. The levels of sciatic nerve thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH), superoxide anion, calcium, myeloperoxidase (MPO), and TNF-α were estimated. Treatment of GA and PreG attenuate PT induced thermal &mechanical hyperalgesia and allodynia symptoms along with the reduction of TBARS, total calcium, TNF-α, superoxide anion, and MPO activity levels; and decreased GSH level. Therefore, it has been concluded that GA has potential neuroprotective actions against PT induced neuropathic pain due to it's anti-oxidant, anti-inflammation and regulation of intracellular calcium ion concentration.

8.
Appl Biochem Biotechnol ; 174(3): 1188-200, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25024132

RESUMO

A label-free electrochemical bianalyte immunosensor has been designed for simultaneous detection of lung cancer biomarkers (anti-MAGE A2 and anti-MAGE A11) using carbon nanotubes-chitosan (CNT-CHI) composite. To achieve this, acid-functionalized single-walled CNTs were used to prepare CNT-CHI gel and electrodes were fabricated by drop casting method onto graphite surface. Lung cancer biomarkers specific antigens (Ag), i.e., MAGE A2 and MAGE A11, were covalently immobilized onto CNT-CHI/graphite electrode separately for fabrication process. Fabricated immunoelectrodes (MAGE A2/CNT-CHI/graphite and MAGE A11/CNT-CHI/graphite) were characterized at each modification step by cyclic voltammetry (CV), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Both immunoelectrodes showed successful detection of respective analytes (anti-MAGE A2 and anti-MAGE A11) from 5 fg mL(-1) to 50 ng mL(-1) using differential pulse voltammetry (DPV). Both Ag/CNT-CHI/graphite immunoelectrodes (using MAGE A2 and MAGE A11) were independently capable of distinguishing specific and nonspecific analytes like CD59, D-dimers, etc. Response studies of both immunoelectrodes revealed successful demonstration of simultaneous detection of anti-MAGE A2 and A11 independently in a single experimental run when exposed to a mixture of various analyte concentrations in different combinations irrespective of the presence of other analyte present in the same vessel.


Assuntos
Antígenos de Neoplasias/isolamento & purificação , Técnicas Biossensoriais , Quitosana/química , Neoplasias Pulmonares/diagnóstico , Proteínas de Neoplasias/isolamento & purificação , Antígenos de Neoplasias/imunologia , Grafite/química , Humanos , Neoplasias Pulmonares/imunologia , Microscopia Eletrônica de Varredura , Nanocompostos/química , Nanotubos de Carbono/química , Proteínas de Neoplasias/imunologia , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Arthritis Rheum ; 65(12): 3026-35, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23918589

RESUMO

OBJECTIVE: Genome-wide association studies (GWAS) and their subsequent meta-analyses have changed the landscape of genetics in rheumatoid arthritis (RA) by uncovering several novel genes. Such studies are heavily weighted by samples from Caucasian populations, but they explain only a small proportion of total heritability. Our previous studies in genetically distinct North Indian RA cohorts have demonstrated apparent allelic/genetic heterogeneity between North Indian and Western populations, warranting GWAS in non-European populations. We undertook this study to detect additional disease-associated loci that may be collectively important in the presence or absence of genes with a major effect. METHODS: High-quality genotypes for >600,000 single-nucleotide polymorphisms (SNPs) in 706 RA patients and 761 controls from North India were generated in the discovery stage. Twelve SNPs showing suggestive association (P < 5 × 10(-5)) were then tested in an independent cohort of 927 RA patients and 1,148 controls. Additional disease-associated loci were determined using support vector machine (SVM) analyses. Fine-mapping of novel loci was performed by using imputation. RESULTS: In addition to the expected association of the HLA locus with RA, we identified association with a novel intronic SNP of ARL15 (rs255758) on chromosome 5 (Pcombined = 6.57 × 10(-6); odds ratio 1.42). Genotype-phenotype correlation by assaying adiponectin levels demonstrated the functional significance of this novel gene in disease pathogenesis. SVM analysis confirmed this association along with that of a few more replication stage genes. CONCLUSION: In this first GWAS of RA among North Indians, ARL15 emerged as a novel genetic risk factor in addition to the classic HLA locus, which suggests that population-specific genetic loci as well as those shared between Asian and European populations contribute to RA etiology. Furthermore, our study reveals the potential of machine learning methods in unraveling gene-gene interactions using GWAS data.


Assuntos
Fatores de Ribosilação do ADP/genética , Artrite Reumatoide/genética , Povo Asiático/genética , Polimorfismo de Nucleotídeo Único , População Branca/genética , Feminino , Frequência do Gene , Loci Gênicos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino
10.
Rheumatol Int ; 33(4): 1047-52, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22833239

RESUMO

Pulmonary artery hypertension (PAH) remains the leading cause of morbidity and mortality in systemic sclerosis, while Raynaud's phenomenon and digital ulcers significantly add to the morbidity in systemic sclerosis (SSc). This study was undertaken to evaluate the role of sildenafil in PAH, Raynaud's phenomenon, and digital ulcers in systemic sclerosis patients. A prospective, open-label, uncontrolled pilot study was done at a tertiary care centre in India to study the safety and efficacy of oral sildenafil in PAH, Raynaud's phenomenon, digital infarcts, and ulcers in SSc. Seventeen patients fulfilling ACR classification criteria for scleroderma and having PAH were recruited. Six-minute walk test, WHO class of dyspnoea, severity of Raynaud's phenomenon, and 2D ECHO were performed in all the study subjects at baseline and at 3 months post-treatment. All patients were treated with oral sildenafil 25 mg three times a day for a period of 3 months. The pre- and post-treatment values of mean pulmonary artery pressure (PAP), 6-min walk test, WHO class of dyspnoea, and severity of Raynaud's phenomenon were compared to look for any significant change. Sixteen patients who completed 3-month follow-up had shown statistically significant improvement in 6-min walk test, WHO class of dyspnoea, severity of Raynaud's phenomenon, and mPAP. Also, there was no occurrence of new digital infarcts or ulcers, and existing ulcers showed signs of healing. Sildenafil is highly efficacious cheaper and safe alternative to other available therapies for SSc-associated PAH, Raynaud's phenomenon, and digital infarcts/ulcers.


Assuntos
Hipertensão Pulmonar/tratamento farmacológico , Piperazinas/uso terapêutico , Doença de Raynaud/tratamento farmacológico , Escleroderma Sistêmico/complicações , Úlcera Cutânea/tratamento farmacológico , Sulfonas/uso terapêutico , Vasodilatadores/uso terapêutico , Adulto , Pressão Arterial/efeitos dos fármacos , Pressão Arterial/fisiologia , Feminino , Humanos , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/fisiopatologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Piperazinas/administração & dosagem , Piperazinas/efeitos adversos , Estudos Prospectivos , Artéria Pulmonar/fisiopatologia , Purinas/administração & dosagem , Purinas/efeitos adversos , Purinas/uso terapêutico , Doença de Raynaud/etiologia , Doença de Raynaud/fisiopatologia , Escleroderma Sistêmico/fisiopatologia , Citrato de Sildenafila , Pele/irrigação sanguínea , Pele/fisiopatologia , Úlcera Cutânea/etiologia , Úlcera Cutânea/fisiopatologia , Sulfonas/administração & dosagem , Sulfonas/efeitos adversos , Resultado do Tratamento , Vasodilatadores/administração & dosagem , Vasodilatadores/efeitos adversos
11.
Indian J Endocrinol Metab ; 16(5): 853-5, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23087883

RESUMO

Primary Sjögren's syndrome (pSS) is a chronic autoimmune disease characterized by a progressive lymphocytic infiltration of the exocrine glands with varying degrees of systemic involvement. Overt or latent renal tubular acidosis (RTA), caused by tubulointerstitial nephropathy, is a common extraglandular manifestation of pSS. Hypokalemic paralysis is a well known, albeit rare complication of severe distal RTA from any cause. Cases of pSS manifesting for the first time as hypokalemic paralysis caused by distal RTA have been rarely reported. We herein present our experience of two cases, who presented to us for evaluation of hypokalemic paralysis and on work up found evidence of distal RTA, which on further work up found to be secondary to pSS. A high index of suspicion for pSS should be kept in all patients with hypokalemic paralysis.

12.
Indian J Hum Genet ; 17(3): 179-87, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22345990

RESUMO

BACKGROUND: Pesticides are used in agriculture to protect crops, but they pose a potential risk to farmers and environment. The aim of the present study is to investigate the relation between the occupational exposure to various pesticides and the presence of DNA damage. MATERIALS AND METHODS: Blood samples of 210 exposed workers (after a day of intense spraying) and 50 control subjects belonging to various districts of Punjab (India) were evaluated using Comet assay. Sixty workers who showed DNA damage were selected for follow up at 5-6 months after the first sampling during a low or null spraying period. RESULTS: Significant differences were found in DNA damage between freshly exposed workers and controls and freshly exposed and followed up cases. There was significant increase in the comet parameters viz. mean comet tail length and frequency of cells showing migration in exposed workers as compared to controls (72.22 ± 20.76 vs. 46.92 ± 8.17, P<0.001; 31.79 vs. 5.77, P<0.001). In the second samples, followed up cases showed significant decrease in frequency of damaged cells as compared to freshly exposed workers of first sampling (P<0.05). The confounding factors such as variable duration of pesticide exposure, age, smoking, drinking and dietary habits etc which were expected to modulate the damage, were instead found to have no significant effect on DNA fragmentation. CONCLUSION: The evidence of a genetic hazard related to exposure resulting from the intensive use of pesticides stresses the need for educational programs for agricultural workers to reduce the use of chemicals in agriculture.

13.
Br J Pharmacol ; 144(7): 889-99, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15685199

RESUMO

We describe the properties of a novel nonpeptide kinin B1 receptor antagonist, NVP-SAA164, and demonstrate its in vivo activity in models of inflammatory pain in transgenic mice expressing the human B1 receptor. NVP-SAA164 showed high affinity for the human B1 receptor expressed in HEK293 cells (K(i) 8 nM), and inhibited increases in intracellular calcium induced by desArg10kallidin (desArg10KD) (IC50 33 nM). While a similar high affinity was observed in monkey fibroblasts (K(i) 7.7 nM), NVP-SAA164 showed no affinity for the rat B1 receptor expressed in Cos-7 cells. In transgenic mice in which the native B1 receptor was deleted and the gene encoding the human B1 receptor was inserted (hB1 knockin, hB1-KI), hB1 receptor mRNA was induced in tissues following LPS treatment. No mRNA encoding the mouse or human B1 receptor was detected in mouse B1 receptor knockout (mB1-KO) mice following LPS treatment. Freund's complete adjuvant-induced mechanical hyperalgesia was similar in wild-type and hB(1)-KI mice, but was significantly reduced in mB1-KO animals. Mechanical hyperalgesia induced by injection of the B1 agonist desArg10KD into the contralateral paw 24 h following FCA injection was similar in wild-type and hB1-KI mice, but was absent in mB1-KO animals. Oral administration of NVP-SAA164 produced a dose-related reversal of FCA-induced mechanical hyperalgesia and desArg10KD-induced hyperalgesia in hB1-KI mice, but was inactive against inflammatory pain in wild-type mice. These data demonstrate the use of transgenic technology to investigate the in vivo efficacy of species selective agents and show that NVP-SAA164 is a novel orally active B1 receptor antagonist, providing further support for the utility of B1 receptor antagonists in inflammatory pain conditions in man.


Assuntos
Analgésicos/uso terapêutico , Benzamidas/uso terapêutico , Antagonistas de Receptor B1 da Bradicinina , Hiperalgesia/tratamento farmacológico , Receptor B1 da Bradicinina/metabolismo , Sulfonamidas/uso terapêutico , Administração Oral , Analgésicos/química , Analgésicos/farmacologia , Animais , Benzamidas/química , Benzamidas/farmacologia , Células COS , Linhagem Celular , Relação Dose-Resposta a Droga , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Humanos , Hiperalgesia/genética , Hiperalgesia/metabolismo , Macaca mulatta , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Ratos , Receptor B1 da Bradicinina/genética , Sulfonamidas/química , Sulfonamidas/farmacologia
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