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1.
Anaesthesia ; 73(2): 195-204, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29150856

RESUMO

Our aim was to prospectively determine the predictive capabilities of SEPSIS-1 and SEPSIS-3 definitions in the emergency departments and general wards. Patients with National Early Warning Score (NEWS) of 3 or above and suspected or proven infection were enrolled over a 24-h period in 13 Welsh hospitals. The primary outcome measure was mortality within 30 days. Out of the 5422 patients screened, 431 fulfilled inclusion criteria and 380 (88%) were recruited. Using the SEPSIS-1 definition, 212 patients had sepsis. When using the SEPSIS-3 definitions with Sequential Organ Failure Assessment (SOFA) score ≥ 2, there were 272 septic patients, whereas with quickSOFA score ≥ 2, 50 patients were identified. For the prediction of primary outcome, SEPSIS-1 criteria had a sensitivity (95%CI) of 65% (54-75%) and specificity of 47% (41-53%); SEPSIS-3 criteria had a sensitivity of 86% (76-92%) and specificity of 32% (27-38%). SEPSIS-3 and SEPSIS-1 definitions were associated with a hazard ratio (95%CI) 2.7 (1.5-5.6) and 1.6 (1.3-2.5), respectively. Scoring system discrimination evaluated by receiver operating characteristic curves was highest for Sequential Organ Failure Assessment score (0.69 (95%CI 0.63-0.76)), followed by NEWS (0.58 (0.51-0.66)) (p < 0.001). Systemic inflammatory response syndrome criteria (0.55 (0.49-0.61)) and quickSOFA score (0.56 (0.49-0.64)) could not predict outcome. The SEPSIS-3 definition identified patients with the highest risk. Sequential Organ Failure Assessment score and NEWS were better predictors of poor outcome. The Sequential Organ Failure Assessment score appeared to be the best tool for identifying patients with high risk of death and sepsis-induced organ dysfunction.


Assuntos
Escores de Disfunção Orgânica , Sepse , Terminologia como Assunto , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecção Hospitalar/mortalidade , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/mortalidade , Valor Preditivo dos Testes , Prevalência , Prognóstico , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade , Sepse/mortalidade , Resultado do Tratamento , Adulto Jovem
2.
Public Health ; 162: 135-146, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30056313

RESUMO

OBJECTIVES: Hand injuries result in major healthcare costs from lack of productivity and disability. With rapid industrialization, the incidence of hand injuries is expected to rise in low- and middle-income countries (LMICs). However, estimates of burden and validated outcome tools are needed for effective resource allocation in the management of these injuries. STUDY DESIGN: We conducted a systematic review to evaluate the burden of hand injuries in LMICs according to Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. METHODS: We searched PubMed, Scopus, Embase, Cochrane Library, PAIS International, African Index Medicus, Global Health, IMMEMR, IMSEAR, Wholis and Bdenf, Lilacs, Scielo, WPRIM, and WHO International Clinical Trials Registry Platform to detect eligible articles with no restrictions on length of follow-up, type of hand injury, or date. RESULTS: We included 17 articles after screening 933 eligible articles based on title, abstract, and full-text screening. There was significant heterogeneity and low quality of evidence. All included articles suggest that hand injuries were associated with work limitations for the majority of patients, and residual pain can further limit their activities. Direct and indirect costs related to treatment account for a major healthcare burden with limited evidence on estimates of long-term cost from disability. CONCLUSIONS: The present systematic review highlights the paucity of high-quality data on the epidemiology, management, and burden of hand injuries in LMICs. The data are heterogeneous, and comprehensive metrics are lacking. Because hand injuries can account for a significant proportion of injury-related disability, reducing the overall burden of hand injuries is of utmost importance.


Assuntos
Países em Desenvolvimento , Traumatismos da Mão/epidemiologia , Traumatismos da Mão/prevenção & controle , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
J Obstet Gynaecol ; 34(3): 241-4, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24483234

RESUMO

A caesarean section at full dilatation (CSFD) can be technically demanding and has consistent association with increased intraoperative trauma. There is evidence that the incidence of caesarean sections at full dilation is on the rise. We report on a prospective study of 50 women undergoing CSFD using a fetal pillow (FP) to elevate the fetal head. Data were compared with historical controls of 124 women without FP use on uterine extensions, uterine incision delivery interval, blood loss, need for transfusion, operating time, length of stay, intensive care unit admission. The FP elevated the fetal head in all 50 women (p < 0.001). We found that patients in the FP group had a lower incidence of extensions (p = 0.03), shorter operating time (p < 0.001), uterine incision to delivery interval (p < 0.001) and shorter length of hospital stay (p < 0.001). Blood loss > 1,000 ml and admission to ICU was also lower but were not statistically significant. There were no significant differences in the fetal complications studied, APGAR scores, admission to neonatal intensive care unit, seizures, neonatal injury or death.


Assuntos
Cesárea/instrumentação , Complicações Intraoperatórias/prevenção & controle , Segunda Fase do Trabalho de Parto , Adolescente , Adulto , Cesárea/estatística & dados numéricos , Feminino , Humanos , Índia/epidemiologia , Complicações Intraoperatórias/epidemiologia , Gravidez , Estudos Prospectivos , Adulto Jovem
4.
Nat Genet ; 7(1): 103-7, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8075631

RESUMO

Breast cancer in men is about a hundredfold less common than in women and this has hindered research into its genetic basis. We have examined 22 families with at least one case of male breast cancer for linkage to the hereditary breast and ovarian cancer locus, BRCA1, on chromosome 17q. We found strong evidence against linkage to BRCA1 (lod score-16.63) and the best estimate of the proportion of linked families was 0% (95% CI 0-18%). Our results indicate that there is a gene(s) other than BRCA1 which predisposes to early-onset breast cancer in women and which confers a higher risk of male breast cancer. Identification of additional pedigrees that include cases of male breast cancer may therefore facilitate the mapping and isolation of this gene.


Assuntos
Neoplasias da Mama/genética , Cromossomos Humanos Par 17 , Neoplasias da Mama/epidemiologia , Feminino , Marcadores Genéticos , Predisposição Genética para Doença , Humanos , Escore Lod , Masculino , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/genética , Linhagem , Fatores de Risco , Fatores Sexuais
5.
Nat Genet ; 15(1): 103-5, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8988179

RESUMO

The breast cancer susceptibility gene BRCA2 on chromosome 13q12-13 has recently been identified. Germline mutations of BRCA2 are predicted to account for approximately 35% of families with multiple case, early onset female breast cancer, and they are also associated with an increased risk of male breast cancer, ovarian cancer, prostate cancer and pancreatic cancer. Germline mutations of a second cancer susceptibility gene BRCA1 (ref. 5), are associated with a strong predisposition to ovarian cancer as well as female breast cancer. Recent studies have suggested that the phenotype in BRCA1 families with respect to the ratio of breast to ovarian cancer varies with the location of the BRCA1 mutation. To determine whether germline mutations in BRCA2 are associated with a similar variation in phenotypic risk, we have analysed the distribution of mutations in 25 families with multiple cases of breast and/or ovarian cancer ascertained in the United Kingdom and Eire. These mutations all lead to premature truncation of BRCA2 as a result of frameshift deletions/insertions or nonsense mutations. Analysis of the mutation distribution along the length of the gene indicates a significant genotype-phenotype correlation. Truncating mutations in families with the highest risk of ovarian cancer relative to breast cancer are clustered in a region of approximately 3.3 kb in exon 11 (P = 0.0004). Published data on mutations in 45 other BRCA2-linked families provide support for this correlation.


Assuntos
Neoplasias da Mama/genética , Mutação em Linhagem Germinativa , Proteínas de Neoplasias/genética , Neoplasias Ovarianas/genética , Fatores de Transcrição/genética , Proteína BRCA2 , Análise Mutacional de DNA , Feminino , Mutação da Fase de Leitura , Predisposição Genética para Doença , Humanos , Masculino , Fatores de Risco
6.
Nat Genet ; 13(2): 238-40, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8640235

RESUMO

The second hereditary breast cancer gene, BRCA2, was recently isolated. Germline mutations of this gene predispose carriers to breast cancer, and, to a lesser extent, ovarian cancer. Loss of heterozygosity (LOH) at the BRCA2 locus has been observed in 30-40% of sporadic breast and ovarian tumours, implying that BRCA2 may act as a tumour suppressor gene in a proportion of sporadic cases. To define the role of BRCA2 in sporadic breast and ovarian cancer, we screened the entire gene for mutations using a combination of techniques in 70 primary breast carcinomas and in 55 primary epithelial ovarian carcinomas. Our analysis revealed alterations in 2/70 breast tumours and none of the ovarian carcinomas. One alteration found in the breast cancers was a 2-basepair (bp) deletion (4710delAG) which was subsequently shown to be a germline mutation, the other was a somatic missense mutation (Asp3095Glu) of unknown significance. Our results suggest that BRCA2 is a very infrequent target for somatic inactivation in breast and ovarian carcinomas, similar to the results obtained for BRCA1.


Assuntos
Neoplasias da Mama/genética , Mutação , Proteínas de Neoplasias/genética , Neoplasias Ovarianas/genética , Fatores de Transcrição/genética , Idoso , Proteína BRCA2 , Sequência de Bases , Primers do DNA , Feminino , Marcadores Genéticos , Heterozigoto , Humanos , Linfócitos/fisiologia , Pessoa de Meia-Idade , Dados de Sequência Molecular , Proteína do Retinoblastoma/genética , Deleção de Sequência
7.
Nat Genet ; 11(4): 428-33, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7493024

RESUMO

Mutations in the BRCA1 gene, discovered in 1994, are associated with an 80-90% lifetime risk of breast cancer. We have analysed 60 families with a history of breast and/or ovarian cancer for germline mutations in BRCA1. Twenty-two different mutations were detected in 32 families (53%), of which 14 are previously unreported. We observed a significant correlation between the location of the mutation in the gene and the ratio of breast to ovarian cancer incidence within each family. Our data suggest a transition in risk such that mutations in the 3' third of the gene are associated with a lower proportion of ovarian cancer. Haplotype analysis supports previous data which suggest some BRCA1 mutation carriers have common ancestors; however, we have found at least two examples where recurrent mutations appear to have arisen independently.


Assuntos
Neoplasias da Mama/genética , Mutação em Linhagem Germinativa , Proteínas de Neoplasias/genética , Neoplasias Ovarianas/genética , Fatores de Transcrição/genética , Proteína BRCA1 , Neoplasias da Mama Masculina/genética , Feminino , Marcadores Genéticos , Testes Genéticos , Genótipo , Haplótipos , Humanos , Masculino , Fenótipo , Fatores de Risco
8.
Nat Genet ; 25(2): 160-5, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10835629

RESUMO

Familial cylindromatosis is an autosomal dominant genetic predisposition to multiple tumours of the skin appendages. The susceptibility gene (CYLD) has previously been localized to chromosome 16q and has the genetic attributes of a tumour-suppressor gene (recessive oncogene). Here we have identified CYLD by detecting germline mutations in 21 cylindromatosis families and somatic mutations in 1 sporadic and 5 familial cylindromas. All mutations predict truncation or absence of the encoded protein. CYLD encodes three cytoskeletal-associated-protein-glycine-conserved (CAP-GLY) domains, which are found in proteins that coordinate the attachment of organelles to microtubules. CYLD also has sequence homology to the catalytic domain of ubiquitin carboxy-terminal hydrolases (UCH).


Assuntos
Genes Supressores de Tumor/genética , Predisposição Genética para Doença/genética , Neoplasias Primárias Múltiplas/genética , Proteínas/genética , Neoplasias Cutâneas/genética , Proteínas Supressoras de Tumor , Sequência de Aminoácidos , Domínio Catalítico , Cromossomos Humanos Par 16/genética , Clonagem Molecular , Mapeamento de Sequências Contíguas , Enzima Desubiquitinante CYLD , Éxons/genética , Feminino , Genes Dominantes/genética , Mutação em Linhagem Germinativa/genética , Humanos , Perda de Heterozigosidade/genética , Masculino , Dados de Sequência Molecular , Mutação/genética , Neoplasias Primárias Múltiplas/patologia , Polimorfismo Genético/genética , Proteínas/química , RNA Mensageiro/análise , RNA Mensageiro/genética , Homologia de Sequência de Aminoácidos , Sitios de Sequências Rotuladas , Neoplasias Cutâneas/patologia , Tioléster Hidrolases/química , Ubiquitina Tiolesterase
9.
Nat Genet ; 24(2): 197-200, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10655070

RESUMO

Testicular germ-cell tumours (TGCT) affect 1 in 500 men and are the most common cancer in males aged 15-40 in Western European populations. The incidence of TGCT has risen dramatically over the last century. Known risk factors for TGCT include a history of undescended testis (UDT), testicular dysgenesis, infertility, previously diagnosed TGCT (ref. 7) and a family history of the disease. Brothers of men with TGCT have an 8-10-fold risk of developing TGCT (refs 8,9), whereas the relative risk to fathers and sons is fourfold (ref. 9). This familial relative risk is much higher than that for most other types of cancer. We have collected samples from 134 families with two or more cases of TGCT, 87 of which are affected sibpairs. A genome-wide linkage search yielded a heterogeneity lod (hlod) score of 2.01 on chromosome Xq27 using all families compatible with X inheritance. We obtained a hlod score of 4.7 from families with at least one bilateral case, corresponding to a genome-wide significance level of P=0.034. The proportion of families with UDT linked to this locus was 73% compared with 26% of families without UDT (P=0.03). Our results provide evidence for a TGCT susceptibility gene on chromosome Xq27 that may also predispose to UDT.


Assuntos
Predisposição Genética para Doença/genética , Germinoma/genética , Neoplasias Testiculares/genética , Cromossomo X , Adolescente , Adulto , Mapeamento Cromossômico , Família , Feminino , Marcadores Genéticos , Germinoma/epidemiologia , Humanos , Incidência , Escore Lod , Masculino , Fatores de Risco , Neoplasias Testiculares/epidemiologia
10.
Br J Cancer ; 106(6): 1234-8, 2012 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-22333603

RESUMO

BACKGROUND: Triple-negative (TN) tumours are the predominant breast cancer subtype in BRCA1 mutation carriers. Recently, it was proposed that all individuals below 50 years of age with TN breast cancer should be offered BRCA testing. We have evaluated the BRCA1 mutation frequency and the implications for clinical practice of undertaking genetic testing in women with TN breast cancer. METHODS: We undertook BRCA1 mutation analysis in 308 individuals with TN breast cancer, 159 individuals from unselected series of breast cancer and 149 individuals from series ascertained on the basis of young age and/or family history. RESULTS: BRCA1 mutations were present in 45 out of 308 individuals. Individuals with TN cancer <50 years had >10% likelihood of carrying a BRCA1 mutation in both the unselected (11 out of 58, 19%) and selected (26 out of 111, 23%) series. However, over a third would not have been offered testing using existing criteria. We estimate that testing all individuals with TN breast cancer <50 years would generate an extra 1200 tests annually in England. CONCLUSION: Women with TN breast cancer diagnosed below 50 years have >10% likelihood of carrying a BRCA1 mutation and are therefore eligible for testing in most centres. However, implementation may place short-term logistical and financial burdens on genetic services.


Assuntos
Proteína BRCA1/genética , Neoplasias da Mama/genética , Testes Genéticos , Fatores Etários , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/metabolismo , Análise Mutacional de DNA , Feminino , Estudos de Associação Genética , Humanos , Incidência , Pessoa de Meia-Idade , Mutação , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo
11.
J Phys Chem C Nanomater Interfaces ; 125(18): 10077-10089, 2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34276857

RESUMO

Porosity in functional oxide nanorods is a recently discovered new type of microstructure, which is not yet fully understood and still under evaluation for its impact on applications in catalysis and gas/ion storage. Here we explore the shape and distribution of pores in ceria in three dimensions using a modified algorithm of geometric tomography as a reliable tool for reconstructing defective and strained nanoobjects. The pores are confirmed as "negative-particle" or "inverse-particle" cuboctahedral shapes located exclusively beneath the flat surface of the rods separated via a sub-5 nm thin ceria wall from the outside. New findings also comprise elongated "negative-rod" defects, seen as embryonic nanotubes, and pores in cube-shaped ceria. Furthermore, we report near-sintering secondary heat treatment of nanorods and cubes, confirming persistence of pores beyond external surface rounding. We support our experiments with molecular modeling and predict that the growth history of voids is via diffusion and aggregation of atomic point defects. In addition, we use density functional theory to show that the relative stability of pore (shape) increases in the order "cuboidal" < "hexagonal-prismatic" < "octahedral". The results indicate that by engineering voids into nanorods, via a high-temperature postsynthetic heat treatment, a potential future alternative route of tuning catalytic activities might become possible.

12.
Science ; 265(5181): 2088-90, 1994 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-8091231

RESUMO

A small proportion of breast cancer, in particular those cases arising at a young age, is due to the inheritance of dominant susceptibility genes conferring a high risk of the disease. A genomic linkage search was performed with 15 high-risk breast cancer families that were unlinked to the BRCA1 locus on chromosome 17q21. This analysis localized a second breast cancer susceptibility locus, BRCA2, to a 6-centimorgan interval on chromosome 13q12-13. Preliminary evidence suggests that BRCA2 confers a high risk of breast cancer but, unlike BRCA1, does not confer a substantially elevated risk of ovarian cancer.


Assuntos
Neoplasias da Mama/genética , Cromossomos Humanos Par 13 , Mapeamento Cromossômico , Feminino , Genes do Retinoblastoma , Marcadores Genéticos , Predisposição Genética para Doença , Humanos , Escore Lod , Masculino , Neoplasias Ovarianas/genética , Linhagem , Fenótipo
13.
Arch Virol ; 154(2): 297-314, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19190853

RESUMO

The discovery of endogenous pararetroviral sequences (EPRVs) has had a deep impact on the approaches needed for diagnosis, taxonomy, safe movement of germplasm and management of diseases caused by pararetroviruses. In this article, we illustrate this through the example of yam (Dioscorea spp.) badnaviruses. To enable progress, it is first necessary to clarify the taxonomical status of yam badnavirus sequences. Phylogeny and pairwise sequence comparison of 121 yam partial reverse transcriptase sequences provided strong support for the identification of 12 yam badnavirus species, of which ten have not been previously named. Virus prevalence data were obtained, and they support the presence of EPRVs in D. rotundata, but not in D. praehensilis, D. abyssinica, D. alata or D. trifida. Five yam badnavirus species characterised by a wide host range seem to be of African origin. Seven other yam badnavirus species with a limited host range are probably of Asian-Pacific origin. Recombination under natural circumstances appears to be rare. Average values of nucleotide intra-species genetic distances are comparable to data obtained for other RNA and DNA virus families. The dispersion scenarios proposed here, combined with the fact that host-switching events appear common for some yam badnaviruses, suggest that the risks linked to introduction via international plant material exchanges are high.


Assuntos
Badnavirus/classificação , Dioscorea/virologia , Ecossistema , Doenças das Plantas/virologia , África , América , Sudeste Asiático , Austrália , Badnavirus/enzimologia , Badnavirus/genética , Dioscorea/classificação , Variação Genética , Melanesia , Dados de Sequência Molecular , Filogenia , DNA Polimerase Dirigida por RNA/genética , Recombinação Genética , Proteínas Virais/genética
14.
Mol Biotechnol ; 61(2): 93-101, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30484144

RESUMO

Cassava brown streak disease (CBSD) has major impacts on yield and quality of the tuberous roots of cassava in Eastern and Central Arica. At least two Potyviridae species cause the disease: Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV). Cloned viral genome sequences known as infectious clones (ICs) have been important in the study of other viruses, both as a means of standardising infectious material and characterising viral gene function. IC construction is often technically challenging for Potyviridae due to sequence instability in E. coli. Here, we evaluate three methods for the construction of infectious clones for CBSD. Whilst a simple IC for in vitro transcription was made for UCBSV isolate 'Kikombe', such an approach failed to deliver full-length clones for CBSV isolates 'Nampula' or 'Tanza', necessitating more complex approaches for their construction. The ICs successfully generated symptomatic infection in the model host N. benthamiana and in the natural host cassava. This shows that whilst generating ICs for CBSV is still a technical challenge, a structured approach, evaluating both in vitro and in planta transcription systems should successfully deliver ICs, allowing further study into the symptomology and virulence factors in this important disease complex.


Assuntos
Clonagem Molecular/métodos , Genoma Viral/genética , Potyviridae/genética , Virologia/métodos , DNA Viral/genética , Íntrons/genética , Manihot/virologia , Doenças das Plantas/virologia , Potyviridae/isolamento & purificação , Potyviridae/patogenicidade , Nicotiana/virologia
15.
Early Hum Dev ; 84(12): 783-5, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18829186

RESUMO

Aicardi-Goutières syndrome (AGS) is a rare, genetically-determined encephalopathy whose importance from a neonatology perspective is magnified because of the risk of misdiagnosis as the sequelae of congenital infection. Molecular advances have shown that AGS can be caused by mutations in any one of at least five genes (four of which have been identified). A recent genotype-phenotype study has shown that a neonatal form of the disease, highly reminiscent of congenital infection, is seen particularly with TREX1 mutations. It seems likely that the enzymes defective in AGS are involved in digesting endogenous nucleic acids (DNA and RNA) produced during normal cell replication, and that a failure of this removal results in inappropriate triggering of the innate immune system. This hypothesis explains the remarkable phenotypic overlap of AGS with congenital infection, where a similar interferon alpha mediated innate immune response is triggered by viral, as opposed to self, nucleic acids.


Assuntos
Encefalite Viral/diagnóstico por imagem , Transtornos Heredodegenerativos do Sistema Nervoso/diagnóstico por imagem , Proteínas/genética , Tomografia Computadorizada por Raios X , Diagnóstico Diferencial , Encefalite Viral/congênito , Exodesoxirribonucleases , Transtornos Heredodegenerativos do Sistema Nervoso/genética , Humanos , Lactente , Recém-Nascido , Masculino , Fenótipo , Fosfoproteínas , Síndrome
16.
JOM (1989) ; 60(3): 33-37, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20617106

RESUMO

The therapeutic application of nanomaterials has been a focus of numerous studies in the past decade. Due to its unique redox properties, cerium oxide (ceria) is finding widespread use in the treatment of medical disorders caused by the reactive oxygen intermediates (ROI). The radical-scavenging role of ceria nanoparticles (nanoceria) have been established, as well as the autocatalytic ability of nanoceria to regenerate under various environmental conditions. The synthesis of nanoceria in biocompatible media has also been reported along with cell viability in order to determine the potential use of nanoceria in biomedical applications.

17.
Mol Cell Biol ; 11(5): 2704-17, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-2017174

RESUMO

The endogenous chicken vitellogenin II (VTGII) gene is transcribed exclusively in hepatocytes in response to estrogen. We previously identified two estrogen response elements (EREs) upstream of this gene. We now present an analysis of the VTGII promoter activated by these EREs in response to estrogen. Chimeric VTGII-CAT genes were cotransfected into LMH chicken hepatoma cells along with an estrogen receptor expression vector, and transient CAT expression was assayed after culturing the cells in the absence or presence of estrogen. An analysis of constructs bearing deletions downstream of the more proximal ERE indicated that promoter elements relevant to transcription in LMH cells extend to between -113 and -96. The relative importance of sequences within the VTGII promoter was examined by using 10 contiguous linker scanner mutations spanning the region from -117 to -24. Although most of these mutations compromised VTGII promoter function, one dramatically increased expression in LMH cells and also rendered the VTGII promoter capable of being activated by cis-linked EREs in fibroblasts cotransfected with an estrogen receptor expression vector. Gel retardation and DNase I footprinting assays revealed four factor-binding sites within this promoter. We demonstrate that three of these sites bind C/EBP, SP1, and USF (or related factors), respectively; the fourth site binds a factor that we denote TF-V beta. The biological relevance of these findings is suggested by the fact that three of these binding sites map to sites previously shown to be occupied in vivo in response to estrogen.


Assuntos
Regulação da Expressão Gênica , Genes , Mutagênese Insercional , Mutagênese Sítio-Dirigida , Regiões Promotoras Genéticas , Vitelogeninas/genética , Animais , Sequência de Bases , Sítios de Ligação , Linhagem Celular , Embrião de Galinha , Galinhas , Deleção Cromossômica , Fibroblastos/metabolismo , Neoplasias Hepáticas Experimentais , Dados de Sequência Molecular , Sondas de Oligonucleotídeos , Reação em Cadeia da Polimerase , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Mapeamento por Restrição , Transcrição Gênica
18.
Mol Cell Biol ; 11(10): 4863-75, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1922023

RESUMO

We screened a chicken liver cDNA expression library with a probe spanning the distal region of the chicken vitellogenin II (VTGII) gene promoter and isolated clones for a transcription factor that we have named VBP (for vitellogenin gene-binding protein). VBP binds to one of the most important positive elements in the VTGII promoter and appears to play a pivotal role in the estrogen-dependent regulation of this gene. The protein sequence of VBP was deduced from a nearly full length cDNA copy and was found to contain a basic/zipper (bZIP) motif. As expected for a bZIP factor, VBP binds to its target DNA site as a dimer. Moreover, VBP is a stable dimer free in solution. A data base search revealed that VBP is related to rat DBP. However, despite the fact that the basic/hinge regions of VBP and DBP differ at only three amino acid positions, the DBP binding site in the rat albumin promoter is a relatively poor binding site for VBP. Thus, the optimal binding sites for VBP and DBP may be distinct. Similarities between the VBP and DBP leucine zippers are largely confined to only four of the seven helical spokes. Nevertheless, these leucine zippers are functionally compatible and appear to define a novel subfamily. In contrast to the bZIP regions, other portions of VBP and DBP are markedly different, as are the expression profiles for these two genes. In particular, expression of the VBP gene commences early in liver ontogeny and is not subject to circadian control.


Assuntos
Proteínas Aviárias , Proteínas de Transporte/genética , Zíper de Leucina/genética , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/genética , Vitelogeninas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Fatores de Transcrição de Zíper de Leucina Básica , Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Galinhas , Clonagem Molecular , Regulação da Expressão Gênica/genética , Substâncias Macromoleculares , Metilação , Dados de Sequência Molecular , Ratos , Alinhamento de Sequência , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Células Tumorais Cultivadas , Xenopus/genética
19.
J Nanosci Nanotechnol ; 7(9): 3354-7, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18019176

RESUMO

Room temperature sensing of hydrogen using randomly oriented tin oxide nanowires has been demonstrated successfully. The role of surface functionalization of nanowires with platinum catalyst in rapid hydrogen detection is also studied. These nanowires were successfully incorporated into a micro-electro-mechanical (MEMS) device. The device can successfully detect hydrogen gas (as low as 500 ppm) with response time as low as 10 sec. Effect of aspect ratio of the nanowires on diffusion of hydrogen molecules in the tin oxide nanowires is elucidated in detail.


Assuntos
Hidrogênio/química , Nanoestruturas/química , Compostos de Estanho/química , Catálise , Eletroquímica/métodos , Elétrons , Gases , Microscopia Eletrônica de Varredura/métodos , Microscopia Eletrônica de Transmissão , Modelos Químicos , Modelos Estatísticos , Nanofios , Platina/química , Temperatura , Fatores de Tempo
20.
Clin Microbiol Infect ; 23(1): 47.e1-47.e10, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27615723

RESUMO

OBJECTIVES: To identify important pathogen recognition receptor (PRR) pathways regulating innate immune responses and outcome in Staphylococcus aureus sepsis. METHODS: We analysed whether candidate PRR pathway genetic variants were associated with killed S. aureus-induced cytokine responses ex vivo and performed follow-up in vitro studies. We tested the association of our top-ranked variant with cytokine responses and clinical outcomes in a prospective multicentre cohort of patients with staphylococcal sepsis. RESULTS: An intronic TLR4 polymorphism and expression quantitative trait locus, rs1927907, was highly associated with cytokine release induced by stimulation of blood from healthy Thai subjects with S. aureus ex vivo. S. aureus did not induce TLR4-dependent NF-κB activation in transfected HEK293 cells. In monocytes, tumor necrosis factor (TNF)-α release induced by S. aureus was not blunted by a TLR4/MD-2 neutralizing antibody, but in a monocyte cell line, TNF-α was reduced by knockdown of TLR4. In Thai patients with staphylococcal sepsis, rs1927907 was associated with higher interleukin (IL)-6 and IL-8 levels as well as with respiratory failure. S. aureus-induced responses in blood were most highly correlated with responses to Gram-negative stimulants whole blood. CONCLUSIONS: A genetic variant in TLR4 is associated with cytokine responses to S. aureus ex vivo and plasma cytokine levels and respiratory failure in staphylococcal sepsis. While S. aureus does not express lipopolysaccharide or activate TLR4 directly, the innate immune response to S. aureus does appear to be modulated by TLR4 and shares significant commonality with that induced by Gram-negative pathogens and lipopolysaccharide.


Assuntos
Inflamação/genética , Sepse/microbiologia , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/microbiologia , Receptor 4 Toll-Like/metabolismo , Adulto , Citocinas/genética , Citocinas/metabolismo , Feminino , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Predisposição Genética para Doença , Variação Genética , Humanos , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Tailândia , Receptor 4 Toll-Like/genética
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