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1.
Science ; 362(6411)2018 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-30309915

RESUMO

Programmed cell death protein-1 (PD-1) and programmed cell death ligand-1 (PD-L1) checkpoint blockade immunotherapy elicits durable antitumor effects in multiple cancers, yet not all patients respond. We report the evaluation of >300 patient samples across 22 tumor types from four KEYNOTE clinical trials. Tumor mutational burden (TMB) and a T cell-inflamed gene expression profile (GEP) exhibited joint predictive utility in identifying responders and nonresponders to the PD-1 antibody pembrolizumab. TMB and GEP were independently predictive of response and demonstrated low correlation, suggesting that they capture distinct features of neoantigenicity and T cell activation. Analysis of The Cancer Genome Atlas database showed TMB and GEP to have a low correlation, and analysis by joint stratification revealed biomarker-defined patterns of targetable-resistance biology. These biomarkers may have utility in clinical trial design by guiding rational selection of anti-PD-1 monotherapy and combination immunotherapy regimens.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Biomarcadores Tumorais/genética , Terapia de Alvo Molecular/métodos , Neoplasias/genética , Neoplasias/terapia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Pontos de Checagem do Ciclo Celular , Marcadores Genéticos , Humanos , Imunoterapia , Inflamação/genética , Mutação , Linfócitos T/imunologia , Transcriptoma , Carga Tumoral/genética
3.
RSC Adv ; 8(9): 5034-5041, 2018 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35539510

RESUMO

Different from the traditional silicone materials, which are not easily ignited, silicone thermoplastic elastomer (Si-TPE) has poor flame retardant properties due to the existence of the hard segments in its molecular chains. In this paper, melamine phosphate (MP), a kind of halogen free flame retardant, was adopted to improve the flame retardancy of Si-TPE. The results showed that MP played the role of flame retardant in both gas and condensed phases due to its nitrogen-phosphorus-containing structure. Inert gases, including nitrogen, steam and ammonia which were released by the degradation of melamine during burning, could take away the heat and dilute the oxygen in the gas phase, and further working with the phosphoric acid, which was generated in the condensed phase, to form a denser and firmer char layer. In this way, Si-TPE/MP composite with good flame retardancy was obtained. Interestingly, MP had little influence on the thermal processability of Si-TPE, even at 28 wt% content, ascribing to its two opposite effects on Si-TPE, but enhanced the comprehensive mechanical properties of Si-TPE with suitable loadings, e.g. when the MP content was 28 wt%, the composite reached UL94-V0 rating, and its tensile strength and Young's modulus were 3.5 MPa and 37.7 MPa, respectively.

4.
EXCLI J ; 16: 25-34, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28337116

RESUMO

The arseniasis in Southwest Guizhou, China has been identified as a unique case of endemic arseniasis caused by exposure to indoor combustion of high As-content coal. Present investigation targeted the microdistribution and speciation of the element arsenic in human hair and environmental samples collected in one of the hyper-endemic villages of arseniasis in the area. Analyses were performed by micro-beam X-ray fluorescence (µ-XRF) and X-ray absorption fine structure (XAFS). The total As level in hair samples of diagnosed patients was detected at almost the same level as in their asymptomatic neighbors. Concentrations in the lateral cut of hair samples were high-low-high (from surface to center). XAFS revealed the coexistence of both the As+3 and As+5 states in hair samples. However, the samples from patients displayed a tendency of higher As+3 / As+5 ratio than the asymptomatic fellow villagers. The µ-XRF mapping of rice grains shows that arsenic penetrates the endosperm, the major edible part of the grain, when rice grains were stored over the open fire of high As-content coal. Synchrotron radiation techniques are suitable to determine arsenic species concentrations in different parts of hair and rice grain samples. As arsenic penetrates the endosperm, rinsing the rice grains with water will remain largely ineffective.

5.
Sci Rep ; 6: 33876, 2016 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-27659771

RESUMO

Nonhuman primates (NHP) are important biomedical animal models for the study of human disease. Of these, the most widely used models in biomedical research currently are from the genus Macaca. However, evolutionary genetic divergence between human and NHP species makes human-based probes inefficient for the capture of genomic regions of NHP for sequencing and study. Here we introduce a new method to resequence the exome of NHP species by a designed capture approach specifically targeted to the NHP, and demonstrate its superior performance on four NHP species or subspecies. Detailed investigation on biomedically relevant genes demonstrated superior capture by the new approach. We identified 28 genes that appeared to be pseudogenized and inactivated in macaque. Finally, we identified 187 genes showing strong evidence for positive selection across all branches of the primate phylogeny including many novel findings.

6.
PLoS One ; 11(1): e0146138, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26745512

RESUMO

Di-n-butyl phthalate (DBP) and its active metabolite, monobutyl phthalate (MBP) are the most common endocrine disrupting chemicals. Many studies indicate that high-doses of DBP and/or MBP exhibit toxicity on testicular function, however, little attention have been paid to the effects of low levels of DBP/MBP on steroidogenesis. As we all know, the steroidogenic acute regulatory protein (StAR) is a key regulator involved in the steroidogenesis. Here we found that, in addition to StAR, MBP/DBP increased the steroidogenesis by a cytoskeletal protein, vimentin. Briefly, in murine adrenocortical tumor (Y1) and the mouse Leydig tumor (MLTC-1) cells, vimentin regulated the secretion of progesterone. When these two cells were exposure to MBP, the DNA demethylation in the vimentin promoter was observed. In addition, MBP also induced the activation of nuclear factor kappa B (NF-κB, a transcriptional regulator of vimentin). These two processes improved the transcriptional elevation of vimentin. Knockdown of NF-κB/vimentin signaling blocked the DBP/MBP-induced steroidogenesis. These in vitro results were also confirmed via an in vivo model. By identifying a mechanism whereby DBP/MBP regulates vimentin, our results expand the understanding of the endocrine disrupting potential of phthalate esters.


Assuntos
DNA/metabolismo , Dibutilftalato/química , Disruptores Endócrinos/química , NF-kappa B/metabolismo , Vimentina/metabolismo , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Dibutilftalato/metabolismo , Dibutilftalato/toxicidade , Disruptores Endócrinos/metabolismo , Disruptores Endócrinos/toxicidade , Masculino , Camundongos , NF-kappa B/antagonistas & inibidores , NF-kappa B/genética , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Ácidos Ftálicos/química , Ácidos Ftálicos/toxicidade , Progesterona/sangue , Progesterona/metabolismo , Regiões Promotoras Genéticas , Interferência de RNA , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Vimentina/antagonistas & inibidores , Vimentina/genética
7.
Toxicol Lett ; 241: 95-102, 2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26581634

RESUMO

The reproductive toxicity of plasticizer di-n-butyl phthalate (DBP) and its active metabolite monobutyl phthalate (MBP) has been demonstrated in rodents. The objective of this study was to explore roles of vimentin and miRNA-200c in steroidogenesis interfered by MBP. Mouse Leydig tumor cells (MLTC-1) and murine adrenocortical tumor cells (Y1) were employed and exposed to various levels of MBP (10(-7), 10(-6), 10(-5) and 10(-4)M). Steroid hormone production was increased significantly when MLTC-1 and Y1 cells were exposed to MBP at 10(-7)M. Additionally, vimentin and steroidogenic acute regulatory protein (StAR) expressions were upregulated at the same dose. It was found that MBP increased the steroidogenesis by facilitating the cholesterol transfer process by vimentin. In contrast, miRNA-200c expression was depressed at doses of MBP (10(-7)M) in both cells. Moreover, vimentin expression and progesterone production were increased in both MLTC-1 and Y1 cells after miRNA-200c expression was artificially inhibited. These results strongly suggested that MBP raised steroid hormone synthesis via upregulated vimentin by miRNA-200c.


Assuntos
Dibutilftalato/toxicidade , MicroRNAs/metabolismo , Esteroides/biossíntese , Vimentina/biossíntese , Vimentina/efeitos dos fármacos , Neoplasias do Córtex Suprarrenal/metabolismo , Animais , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Tumor de Células de Leydig/metabolismo , Masculino , Camundongos , MicroRNAs/efeitos dos fármacos , Fosfoproteínas/efeitos dos fármacos , Progesterona/biossíntese , Transfecção , Regulação para Cima/efeitos dos fármacos
8.
Zhonghua Nan Ke Xue ; 21(12): 1064-70, 2015 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-26817296

RESUMO

OBJECTIVE: To investigate the impact of in utero exposure to di-n-butyl phthalate (DBP) on the apoptosis of testicular cells in the pubertal male rat offspring. METHODS: Ten pregnant SD rats were randomly divided into a control and an experimental group to be treated intragastrically with olive oil (1 ml per day) and DBP (500 mg per kg of body weight per day) respectively between gestation days 12 and 19. At the pubertal age (postnatal day 45, PND 45), the testes of the male rat offspring were removed for observation of the cell structure under the transmission electron microscope and the development of different spermatogenetic cells by HE staining. The apoptosis of testicular cells was detected by the TUNEL method, the expressions of the apoptosis-regulating proteins Bcl-2, Bcl-XL, Bax and p53 were determined by immunohistochemistry and Western blot, and the data obtained were compared between the two groups by t-test. RESULTS: Transmission electron microscopy revealed increased apoptosis and vacuolization of testicular cells in the PND-45 rat offspring, HE staining showed markedly decreased numbers of different spermatogenetic cells, TUNEL manifested significantly increased apoptosis of testicular cells in the experimental group as compared with the control (12.00 ± 5. 22 vs 3.17 ± 1.47, P < 0.01), and immunohistochemistry and Western blot exhibited remarkably higher expressions of Bax and p53 in the former than in the latter group (P < 0.05). CONCLUSION: In utero exposure to DBP can increase the apoptosis of germ cells and Sertoli cells, induce the vacuolization of testicular cells, and significantly elevate the expressions of the apoptosis-promoting proteins Bax and p53 in the pubertal male rat offspring.


Assuntos
Apoptose , Dibutilftalato/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal , Células de Sertoli/patologia , Testículo/patologia , Animais , Peso Corporal , Feminino , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Gravidez , Ratos , Ratos Sprague-Dawley , Células de Sertoli/citologia , Espermatogênese , Testículo/citologia , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo
9.
Int Arch Occup Environ Health ; 83(4): 433-40, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19967385

RESUMO

BACKGROUND: A few villages in Southwest Guizhou, China represented a unique case of arseniasis due to indoor combustion of high arsenic-content coal. The present study is aimed to analyze the contribution of possible factors or of their combination to excess prevalence of arseniasis in the exposed population. METHODS: An epidemiological investigation was conducted in all the members of three large ethnic, patrilineal clans in one of the hyperendemic villages (702 residents in 178 families, including 408 Han and 294 Hmong) where farmers of different ethnic origin have been living together in the same village for generations. A multilevel model logistic regression analysis was performed. RESULTS: The arseniasis prevalence was found to associate with the duration of As indoor exposure (years of high As coal burning and of poorly ventilated traditional stove using) and is largely dependent on the subject's ethnicity and clan consanguinity, too. The prevalence of arseniasis in ethnic Han residents was significantly higher than that in their Hmong neighbors (35.0 vs 4.8% OR = 15.18, 95% CI = 3.45-67.35). Notable variances of arseniasis prevalence were observed not only between the ethnic Han clans (G1, G3, and B) and Hmong clan P, but also between different lineages (G1 and G2) inside the ethnic Han clan. Smokers suffered more frequently from arseniasis than non-smokers (47.3 vs 15.7% OR = 5.42, 95% CI = 2.25-12.93). CONCLUSIONS: Arseniasis prevalence in this unique exposure case was impacted by an array of multiple factors. Besides a long-term indoor exposure to As, the ethnicity or the clan consanguinity of exposed subjects may play an important role, too.


Assuntos
Poluição do Ar em Ambientes Fechados/efeitos adversos , Intoxicação por Arsênico/etnologia , Carvão Mineral/efeitos adversos , Exposição Ambiental/efeitos adversos , Vigilância da População , Adolescente , Adulto , Idoso , Poluição do Ar em Ambientes Fechados/análise , Intoxicação por Arsênico/etiologia , Intoxicação por Arsênico/genética , Criança , China/epidemiologia , Carvão Mineral/análise , Consanguinidade , Estudos Transversais , Exposição Ambiental/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Análise de Regressão , Fatores de Risco , População Rural/estatística & dados numéricos , Adulto Jovem
10.
Arch Toxicol ; 84(1): 17-24, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19834688

RESUMO

More than 2,000 arsenic-related skin lesions (as at 2002) in a few villages of China's Southwest Guizhou Autonomous Prefecture represent a unique case of endemic arseniasis related with indoor combustion of high-arsenic coal. The skin lesion prevalence was significantly higher in ethnic Han villagers than in ethnic Hmong villagers. This study was focused on a possible involvement of XPD/ERCC2 G23591A and A35931C polymorphisms in risk modulation of skin lesions and in the body burden of As in this unique case of As exposure. G23591A and A35931C were genotyped by a PCR-based procedure. Total As contents in hair and urine samples as well as environmental samples of the homes of the two ethnic clans were analysed. A significant higher presentation of A/A35931 (homozygous wild) genotype in both clans was found in skin lesion patients, compared with their asymptomatic fellow villagers (67.1 vs. 46.3%, OR 2.36, 95% CI 1.35-4.14, P=0.002). Interestingly, the population frequencies of the A/A35931 genotype did not show significant differences between ethnic Han villagers and their Hmong neighbours (47.1 vs. 45.5%). Very low frequencies of homozygous and heterozygous variant genotypes of G23591A were recorded in the residents in target village. G/A23591 and A/A23591 were detected only in 3.2% (8/244) and 0.8% (2/244) of the villagers, respectively. The polymorphic status at the locus of A35931C might modulate the risk for arsenic-related skin lesions in the investigated groups.


Assuntos
Intoxicação por Arsênico/epidemiologia , Carvão Mineral/toxicidade , Doenças Endêmicas , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único/genética , Dermatopatias/epidemiologia , Proteína Grupo D do Xeroderma Pigmentoso/genética , Poluição do Ar em Ambientes Fechados/efeitos adversos , Arsênio/análise , Arsênio/urina , Intoxicação por Arsênico/complicações , Carga Corporal (Radioterapia) , China/epidemiologia , Monitoramento Ambiental/estatística & dados numéricos , Monitoramento Epidemiológico , Etnicidade/genética , Feminino , Frequência do Gene/genética , Genótipo , Cabelo/química , Humanos , Masculino , Prevalência , População Rural/estatística & dados numéricos , Dermatopatias/complicações , Dermatopatias/genética , Fumaça/efeitos adversos
11.
PLoS Comput Biol ; 5(12): e1000608, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20019791

RESUMO

High-throughput methods such as EST sequencing, microarrays and deep sequencing have identified large numbers of alternative splicing (AS) events, but studies have shown that only a subset of these may be functional. Here we report a sensitive bioinformatics approach that identifies exons with evidence of a strong RNA selection pressure ratio (RSPR)--i.e., evolutionary selection against mutations that change only the mRNA sequence while leaving the protein sequence unchanged--measured across an entire evolutionary family, which greatly amplifies its predictive power. Using the UCSC 28 vertebrate genome alignment, this approach correctly predicted half to three-quarters of AS exons that are known binding targets of the NOVA splicing regulatory factor, and predicted 345 strongly selected alternative splicing events in human, and 262 in mouse. These predictions were strongly validated by several experimental criteria of functional AS such as independent detection of the same AS event in other species, reading frame-preservation, and experimental evidence of tissue-specific regulation: 75% (15/20) of a sample of high-RSPR exons displayed tissue specific regulation in a panel of ten tissues, vs. only 20% (4/20) among a sample of low-RSPR exons. These data suggest that RSPR can identify exons with functionally important splicing regulation, and provides biologists with a dataset of over 600 such exons. We present several case studies, including both well-studied examples (GRIN1) and novel examples (EXOC7). These data also show that RSPR strongly outperforms other approaches such as standard sequence conservation (which fails to distinguish amino acid selection pressure from RNA selection pressure), or pairwise genome comparison (which lacks adequate statistical power for predicting individual exons).


Assuntos
Processamento Alternativo , Biologia Computacional/métodos , Modelos Genéticos , RNA/genética , Alinhamento de Sequência/métodos , Animais , Proteínas de Transporte/genética , Etiquetas de Sequências Expressas , Genoma , Humanos , Camundongos , Proteínas do Tecido Nervoso/genética , Análise de Sequência com Séries de Oligonucleotídeos , Receptores de N-Metil-D-Aspartato/genética , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas de Transporte Vesicular/genética
12.
Int Arch Occup Environ Health ; 81(1): 9-17, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17387503

RESUMO

OBJECTIVE: This study was directed to ascertain the mortality of a group of arseniasis patients in an endemic rural township in Southwest China, where the residents were exposed for decades to indoor combustion of high arsenic coal. METHODS: All the diagnosed arseniasis cases registered in 1991 were defined as the target population, which were assigned to three symptom subgroups by the severity of dermal lesions. The death cases were surveyed and checked. The follow-up period was 12.5 years. The standardized mortality ratio (SMR) of all death causes combined, all cancers combined, and the cancers at every site were analyzed. The age standardized mortality rates (ASMRs) were calculated in three subgroups using the procedure of standardization. RESULTS: One hundred and six death cases were recorded. Liver cirrhosis, non-melanotic skin cancer, lung and liver cancer were the four most prevalent death causes and referred to 70.8% (75/106) of the total death cases. The mortality of all death causes combined was not higher than that of the whole of China in 2001 (SMR = 0.76, 95% CI 0.63-0.93). The crude mortality rate of non-melanotic skin cancer in males reached up to 128.66/10(5). SMRs of lung cancer and larynx cancer in males (SMRs 2.84 and 27.27, 95% CIs 1.51-4.86 and 5.61-79.62, respectively) significantly exceeded the levels for all male Chinese. ASMRs of all death causes combined, all cancers combined and non-melanotic skin cancer in males of the severe dermal symptoms subgroup were significantly higher than those in medium and/or mild dermal symptom subgroups. CONCLUSIONS: A significantly increased mortality due to lung cancer and non-melanotic skin cancer was confirmed, alike the situation in other arseniasis endemic areas in the world. No significant elevation of mortality due to liver cancer and bladder cancer was observed. Male arseniasis patients diagnosed with severe skin lesions face higher risks of malignancies and of non-melanotic skin cancer in particular in the following years.


Assuntos
Poluição do Ar em Ambientes Fechados/efeitos adversos , Intoxicação por Arsênico/mortalidade , Carvão Mineral/intoxicação , Adulto , Idoso , Intoxicação por Arsênico/etiologia , Causas de Morte , China/epidemiologia , Feminino , Incêndios , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , População Rural
13.
Arch Toxicol ; 81(8): 545-51, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17318627

RESUMO

A total of 2,402 cases of arsenic-related skin lesions (as of 2002) in a few villages of China's Southwest Guizhou Autonomous Prefecture represent a unique case of endemic arseniasis related with indoor combustion of high arsenic coal. A significant difference of skin lesion prevalence was observed between two clans of different ethnicities (Hmong and Han) in one of the hyperendemic villages in this prefecture. This study was focused on a possible involvement of GST T1 and M1 polymorphisms in risk modulation of skin lesions and in the body burden of As in this unique case of As exposure. GST T1 and M1 polymorphisms were genotyped by an allele-specific PCR-based procedure. Total As contents in hair and urine samples as well as environmental samples of the homes of the two ethnic clans were analyzed. No significant deviations in the population frequencies of GST T1 and M1 0/0 genotypes or their combination were recorded between diagnosed skin lesion patients and asymptomatic individuals in both clans. Significantly higher As contents in hair and urine were observed in GSTM1 0/0 carriers, not in GSTT1 0/0 carriers. After stratified by ethnicity and gender, a statistically significant association of the GSTM1 0/0 genotype and higher As content in hair was only confirmed in the subgroups of ethnic Han clan members and all male villagers, not in ethnic Hmong clan members or in females. GST T1 and M1 homozygous deletions were not associated with an increased susceptibility to skin lesions in long-term exposure to indoor combustion of high As coal. The polymorphic status at the locus of GSTM1 might modulate individual's body burden of total As in some Chinese ethnic groups.


Assuntos
Poluentes Atmosféricos/análise , Arsênio/análise , Carvão Mineral , Glutationa Transferase/genética , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/urina , Poluição do Ar em Ambientes Fechados , Arsênio/toxicidade , Arsênio/urina , Intoxicação por Arsênico/epidemiologia , Intoxicação por Arsênico/genética , Intoxicação por Arsênico/metabolismo , China/epidemiologia , Monitoramento Ambiental , Monitoramento Epidemiológico , Etnicidade/genética , Feminino , Genótipo , Cabelo/química , Humanos , Masculino , Polimorfismo Genético , Dermatopatias/induzido quimicamente , Dermatopatias/epidemiologia , Dermatopatias/genética , Dermatopatias/metabolismo
14.
Pharmacogenet Genomics ; 16(12): 863-71, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17108810

RESUMO

OBJECTIVES: A total of 2402 patients with arsenic-related skin lesions, such as hyperkeratosis, hyperpigmentation or hypopigmentation, or even skin cancer in a few villages in Southwest Guizhou Autonomous Prefecture, China represent a unique case of endemic arsenism related with indoor combustion of high arsenic coal. This study aimed to investigate the cluster of arsenism cases and the possible relevant factors including GSTP1 polymorphism in two clans of different ethnic origin living in one village for generations. METHODS: A questionnaire-based study was performed in 170 Miao clan P members, 10 of whom had arsenic-related skin diseases, and 153 Han clan G1 members, 50 of whom had arsenic-related skin diseases. The data were checked against the registration archives since the 1980s. At the same time, arsenic concentrations in samples of coal, indoor air, drinking water, corn and chilli pepper that were once baked over the stoves for desiccation, as well as in samples of urine and hair of clan members were determined. Glutathione S-transferase P1 (GSTP1) A1578G polymorphism was genotyped by a restriction fragment length polymorphism-based procedure. RESULTS: Arsenism morbidity in Miao clan P was significantly lower than in the neighbouring Han clan G1 [5.9 vs. 32.7%, odds ratio (OR)=0.13, 95% confidence interval (CI): 0.06-0.27, P<0.0001]. No sex differences were confirmed inside both clans. Analyses of the environmental samples indicated that Miao clan P members were exposed to higher amounts of arsenic via inhalation and food ingestion. Hair and urine samples also proved a higher arsenic body burden in ethnic Miao individuals. No corresponding differences by sex were found. Higher frequencies of combined mutant genotype G/G1578 and A/G1578 (OR=4.72, 95% CI: 2.34-9.54, P<0.0001) and of mutant allele G1578 (OR=3.22, 95% CI: 2.00-5.18, P<0.0001) were detected in diagnosed arsenism patients than in non-diseased individuals. The Miao individuals showed a lower percentage of combined mutant genotypes (30.6 vs. 52.7%, OR=0.40, 95% CI: 0.19-0.84, P=0.015) as well as of mutant allele G1578 (OR=0.46, 95% CI: 0.24-0.88, P=0.017) than their Han neighbours. CONCLUSIONS: Genetic predisposition influences dermal arsenism toxicity. The GSTP1 A1578G (Ile105Val) status might be a susceptibility factor for arsenic-related skin lesions.


Assuntos
Intoxicação por Arsênico/enzimologia , Intoxicação por Arsênico/genética , Etnicidade/genética , Glutationa S-Transferase pi/genética , Dermatopatias/enzimologia , Dermatopatias/genética , Adolescente , Adulto , Poluição do Ar em Ambientes Fechados/efeitos adversos , Poluição do Ar em Ambientes Fechados/análise , Substituição de Aminoácidos , Arsênio/análise , Intoxicação por Arsênico/epidemiologia , Intoxicação por Arsênico/etiologia , Criança , Pré-Escolar , China/epidemiologia , Carvão Mineral/efeitos adversos , Feminino , Contaminação de Alimentos/análise , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Farmacogenética , Polimorfismo de Nucleotídeo Único , Dermatopatias/epidemiologia , Dermatopatias/etiologia
15.
BMC Bioinformatics ; 7: 252, 2006 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-16684350

RESUMO

BACKGROUND: As phenotypic features derived from heritable characters, the topologies of metabolic pathways contain both phylogenetic and phenetic components. In the post-genomic era, it is possible to measure the "phylophenetic" contents of different pathways topologies from a global perspective. RESULTS: We reconstructed phylophenetic trees for all available metabolic pathways based on topological similarities, and compared them to the corresponding 16S rRNA-based trees. Similarity values for each pair of trees ranged from 0.044 to 0.297. Using the quartet method, single pathways trees were merged into a comprehensive tree containing information from a large part of the entire metabolic networks. This tree showed considerably higher similarity (0.386) to the corresponding 16S rRNA-based tree than any tree based on a single pathway, but was, on the other hand, sufficiently distinct to preserve unique phylogenetic information not reflected by the 16S rRNA tree. CONCLUSION: We observed that the topology of different metabolic pathways provided different phylogenetic and phenetic information, depicting the compromise between phylogenetic information and varying evolutionary pressures forming metabolic pathway topologies in different organisms. The phylogenetic information content of the comprehensive tree is substantially higher than that of any tree based on a single pathway, which also gave clues to constraints working on the topology of the global metabolic networks, information that is only partly reflected by the topologies of individual metabolic pathways.


Assuntos
Mapeamento Cromossômico/métodos , Expressão Gênica/fisiologia , Modelos Genéticos , Filogenia , Proteínas/genética , Proteínas/metabolismo , RNA Ribossômico 16S/genética , Análise de Sequência de RNA/métodos , Transdução de Sinais/genética , Simulação por Computador
16.
PLoS Comput Biol ; 2(5): e47, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16699597

RESUMO

Transcription factors with a large number of target genes--transcription hub(s), or THub(s)--are usually crucial components of the regulatory system of a cell, and the different patterns through which they transfer the transcriptional signal to downstream cascades are of great interest. By profiling normalized abundances (A(N)) of basic regulatory patterns of individual THubs in the yeast Saccharomyces cerevisiae transcriptional regulation network under five different cellular states and environmental conditions, we have investigated their preferences for different basic regulatory patterns. Subgraph-normalized abundances downstream of individual THubs often differ significantly from that of the network as a whole, and conversely, certain over-represented subgraphs are not preferred by any THub. The THub preferences changed substantially when the cellular or environmental conditions changed. This switching of regulatory pattern preferences suggests that a change in conditions does not only elicit a change in response by the regulatory network, but also a change in the mechanisms by which the response is mediated. The THub subgraph preference profile thus provides a novel tool for description of the structure and organization between the large-scale exponents and local regulatory patterns.


Assuntos
Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ciclo Celular , Regulação Fúngica da Expressão Gênica/genética , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Transcrição Gênica/genética
17.
Biochem Biophys Res Commun ; 345(1): 302-9, 2006 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-16690033

RESUMO

It has been a challenging task to integrate high-throughput data into investigations of the systematic and dynamic organization of biological networks. Here, we presented a simple hierarchical clustering algorithm that goes a long way to achieve this aim. Our method effectively reveals the modular structure of the yeast protein-protein interaction network and distinguishes protein complexes from functional modules by integrating high-throughput protein-protein interaction data with the added subcellular localization and expression profile data. Furthermore, we take advantage of the detected modules to provide a reliably functional context for the uncharacterized components within modules. On the other hand, the integration of various protein-protein association information makes our method robust to false-positives, especially for derived protein complexes. More importantly, this simple method can be extended naturally to other types of data fusion and provides a framework for the study of more comprehensive properties of the biological network and other forms of complex networks.


Assuntos
Bases de Dados de Proteínas , Modelos Biológicos , Mapeamento de Interação de Proteínas/métodos , Proteoma/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Transdução de Sinais/fisiologia , Algoritmos , Análise por Conglomerados , Simulação por Computador , Sistemas de Gerenciamento de Base de Dados , Integração de Sistemas , Interface Usuário-Computador
18.
Biochem Biophys Res Commun ; 343(3): 950-5, 2006 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-16574072

RESUMO

The Hfq-binding small RNAs (sRNAs) have recently drawn much attention as regulators of translation in Escherichia coli. We attempt to identify the targets of this class of sRNAs in genome scale and gain further insight into the complexity of translational regulation induced by Hfq-binding sRNAs. Using a new alignment algorithm, most known negatively regulated targets of Hfq-binding sRNAs were identified. The results also show several interesting aspects of the regulatory function of Hfq-binding sRNAs.


Assuntos
Proteínas de Escherichia coli/metabolismo , Escherichia coli/genética , Fator Proteico 1 do Hospedeiro/metabolismo , RNA Bacteriano/química , RNA não Traduzido/química , Algoritmos , Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica , Heme/análogos & derivados , Heme/biossíntese , Óperon , RNA Bacteriano/genética , RNA Bacteriano/metabolismo , RNA não Traduzido/genética , RNA não Traduzido/metabolismo
19.
FEBS Lett ; 580(7): 1891-6, 2006 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-16516894

RESUMO

MOTIVATION: Predicting protein function accurately is an important issue in the post-genomic era. To achieve this goal, several approaches have been proposed deduce the function of unclassified proteins through sequence similarity, co-expression profiles, and other information. Among these methods, the global optimization method (GOM) is an interesting and powerful tool that assigns functions to unclassified proteins based on their positions in a physical interactions network [Vazquez, A., Flammini, A., Maritan, A. and Vespignani, A. (2003) Global protein function prediction from protein-protein interaction networks, Nat. Biotechnol., 21, 697-700]. To boost both the accuracy and speed of GOM, a new prediction method, MFGO (modified and faster global optimization) is presented in this paper, which employs local optimal repetition method to reduce calculation time, and takes account of topological structure information to achieve a more accurate prediction. CONCLUSION: On four proteins interaction datasets, including Vazquez dataset, YP dataset, DIP-core dataset, and SPK dataset, MFGO was tested and compared with the popular MR (majority rule) and GOM methods. Experimental results confirm MFGO's improvement on both speed and accuracy. Especially, MFGO method has a distinctive advantage in accurately predicting functions for proteins with few neighbors. Moreover, the robustness of the approach was validated both in a dataset containing a high percentage of unknown proteins and a disturbed dataset through random insertion and deletion. The analysis shows that a moderate amount of misplaced interactions do not preclude a reliable function assignment.


Assuntos
Algoritmos , Modelos Moleculares , Proteínas/fisiologia , Proteínas de Saccharomyces cerevisiae/fisiologia , Fatores de Tempo
20.
Nucleic Acids Res ; 34(Database issue): D150-2, 2006 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-16381834

RESUMO

The noncoding RNAs and protein related biomacromolecules interaction database (NPInter; http://bioinfo.ibp.ac.cn/NPInter or http://www.bioinfo.org.cn/NPInter) is a database that documents experimentally determined functional interactions between noncoding RNAs (ncRNAs) and protein related biomacromolecules (PRMs) (proteins, mRNAs or genomic DNAs). NPInter intends to provide the scientific community with a comprehensive and integrated tool for efficient browsing and extraction of information on interactions between ncRNAs and PRMs. Beyond cataloguing details of these interactions, the NPInter will be useful for understanding ncRNA function, as it adds a very important functional element, ncRNAs, to the biomolecule interaction network and sets up a bridge between the coding and the noncoding kingdoms.


Assuntos
Bases de Dados Genéticas , RNA não Traduzido/metabolismo , Animais , DNA/metabolismo , Humanos , Internet , Camundongos , RNA Mensageiro/metabolismo , RNA não Traduzido/classificação , RNA não Traduzido/fisiologia , Proteínas de Ligação a RNA/metabolismo , Interface Usuário-Computador
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