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1.
Mar Pollut Bull ; 124(2): 573-586, 2017 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-28314615

RESUMO

Marine ecosystems are subject to anthropogenic change at global, regional and local scales. Global drivers interact with regional- and local-scale impacts of both a chronic and acute nature. Natural fluctuations and those driven by climate change need to be understood to diagnose local- and regional-scale impacts, and to inform assessments of recovery. Three case studies are used to illustrate the need for long-term studies: (i) separation of the influence of fishing pressure from climate change on bottom fish in the English Channel; (ii) recovery of rocky shore assemblages from the Torrey Canyon oil spill in the southwest of England; (iii) interaction of climate change and chronic Tributyltin pollution affecting recovery of rocky shore populations following the Torrey Canyon oil spill. We emphasize that "baselines" or "reference states" are better viewed as envelopes that are dependent on the time window of observation. Recommendations are made for adaptive management in a rapidly changing world.


Assuntos
Mudança Climática , Pesqueiros , Poluição por Petróleo , Poluição da Água , Animais , Ecossistema , Ecotoxicologia/métodos , Inglaterra , Meio Ambiente , Peixes , Biologia Marinha/métodos , Compostos de Trialquitina/toxicidade , Poluentes Químicos da Água/toxicidade
2.
Eur Respir J ; 32(6): 1625-30, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18614559

RESUMO

The aim of the present study was to evaluate the clinical characteristics, prognoses and predictors of mortality of patients with pulmonary tuberculosis (TB) with acute respiratory failure (ARF), and to investigate the adjunctive use of corticosteroids in such cases. TB patients with ARF requiring mechanical ventilation (n = 90) were enrolled retrospectively during 1989-2006. The patients were divided into two groups: tuberculous pneumonia (TBP; n = 66), and miliary TB (MTB; n = 24). The TBP patients were older than the MTB patients (mean age 68.0 versus 54.5 yrs), and the mean+/-SD interval from hospital admission to start of anti-TB treatment was longer for the TBP than for the MTB group (5.0+/-7.0 versus 2.8+/-2.5 days). However, there was no difference in in-hospital mortality rate between the two groups (68.2 versus 58.3%). In the TBP patients, multivariate analysis showed that advanced age and shock unrelated to sepsis were associated with poor outcomes. Even though corticosteroid use was a predictor of survival in TBP patients, it was difficult to conclusively determine the efficacy of corticosteroids in TBP with ARF because of the retrospective study design. The present study reveals the need for randomised controlled trials to clarify the role of corticosteroids as adjunctive therapy in the management of tuberculous pneumonia with acute respiratory failure.


Assuntos
Insuficiência Respiratória/complicações , Tuberculose Pulmonar/complicações , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia/complicações , Pneumonia/diagnóstico , Respiração Artificial , Insuficiência Respiratória/diagnóstico , Estudos Retrospectivos , Resultado do Tratamento , Tuberculose Miliar/complicações , Tuberculose Miliar/diagnóstico , Tuberculose Pulmonar/diagnóstico
3.
Ann Oncol ; 12(2): 151-60, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11300317

RESUMO

Colorectal cancer (CRC) is a significant cause of mortality in Western populations. About 15% of CRC patients report a family history of the disease. Studies on individuals with a genetic predisposition to CRC have been responsible for significant advances in the understanding of this disease. Thus, although developments in molecular biology have been mainly restricted to a minority of individuals with a hereditary background, information obtained from this group may affect the diagnosis and therapy of sporadic CRCs as well. Deficiency in the DNA mismatch repair (MMR) system results in microsatellite instability (MSI). Individuals from hereditary non-polyposis colorectal cancer (HNPCC) kindreds with germline mutations in genes involved in MMR may benefit from clinical screening programs. The higher frequency of MSI in HNPCC than in sporadic tumours suggests that involvement of MMR genes in sporadic adenomas may be uncommon. Consequently


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais/genética , Repetições de Microssatélites/genética , Mutação , Adulto , Análise Mutacional de DNA , Reparo do DNA , Marcadores Genéticos , Genótipo , Humanos , Pessoa de Meia-Idade , Fenótipo , Prognóstico
4.
Dis Colon Rectum ; 43(11): 1535-9, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11089588

RESUMO

PURPOSE: The aim of this study was to establish the length of telomeres in familial adenomatous polyposis-associated desmoids. METHODS: DNA from 21 desmoids and five desmoid precursor lesions was digested with HinfI and RsaI restriction enzymes. Southern blotting of the resolved fragments was performed, and the membranes were hybridized with a specific probe attached to a chemiluminescent substrate. Terminal restriction fragment lengths were measured. RESULTS: The median terminal restriction fragment length for the desmoids was 8 (range, 6-9.6) vs. 7.7 (range, 6.4-9.9) kb for their controls. Median terminal restriction fragment length for the desmoid precursor lesions was 9 (range, 7.8-10.4) vs. 8.8 (range, 6.8-10.9) kb for their controls. There was no statistically significant difference between samples and their controls. CONCLUSION: Immortality may not be necessary for desmoid development, or there may be other mechanisms maintaining telomere length. Novel treatments involving telomerase inhibition will be inappropriate in the management of desmoids.


Assuntos
Neoplasias Abdominais/genética , Polipose Adenomatosa do Colo/genética , DNA de Neoplasias/análise , Fibromatose Agressiva/genética , Telômero/genética , Neoplasias Abdominais/complicações , Polipose Adenomatosa do Colo/complicações , Adolescente , Adulto , Southern Blotting , Feminino , Fibromatose Agressiva/etiologia , Marcadores Genéticos , Humanos , Masculino , Pessoa de Meia-Idade
5.
Environ Res ; 83(2): 180-7, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10856191

RESUMO

This study included three different experiments for benzene exposures associated with active smoking. In the first experiment, the mean exhaled breath benzene concentrations measured 1 min after an active smoke ranged from 58.1 to 81.3 microgram/m(3), depending on the commercial cigarette brand, while those measured prior to an active smoke ranged from 15.9 to 19.2 microgram/m(3). The postexposure breath concentrations were much higher than the mean breath concentrations reported by some previous studies whose exposure conditions and postsampling times were not controlled. Similar to some previous decay studies conducted for different volatile organic compounds in different microenvironments, our second experiment showed that there was a rapid fall in the breath concentration and thereafter the decrease was much slower. One-compartment half-lives ranged from 30.1 to 57.8 min. Two-compartment half-lives ranged from 3.2 to 25.7 min for the first half-life and from 67 to 462 min for the second half-life. In the final repeated smoke experiment conducted with two specified time intervals, the breath concentrations showed increasing trends for both the pre- and the post exposure concentrations, with few exceptions. However, none of the changes were statistically significant at P<0.05.


Assuntos
Benzeno/análise , Fumar , Adulto , Benzeno/farmacocinética , Testes Respiratórios/métodos , Feminino , Meia-Vida , Humanos , Exposição por Inalação , Masculino , Sensibilidade e Especificidade
6.
Nat Med ; 5(9): 1071-5, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10470088

RESUMO

APC is often cited as a prime example of a tumor suppressor gene. Truncating germline and somatic mutations (or, infrequently, allelic loss) occur in tumors in FAP (familial adenomatous polyposis). Most sporadic colorectal cancers also have two APC mutations. Clues from attenuated polyposis, missense germline variants with mild disease and the somatic mutation cluster region (codons 1,250-1,450) indicate, however, that APC mutations might not result in simple loss of protein function. We have found that FAP patients with germline APC mutations within a small region (codons 1,194-1,392 at most) mainly show allelic loss in their colorectal adenomas, in contrast to other FAP patients, whose 'second hits' tend to occur by truncating mutations in the mutation cluster region. Our results indicate that different APC mutations provide cells with different selective advantages, with mutations close to codon 1,300 providing the greatest advantage. Allelic loss is selected strongly in cells with one mutation near codon 1,300. A different germline-somatic APC mutation association exists in FAP desmoids. APC is not, therefore, a classical tumor suppressor. Our findings also indicate a new mechanism for disease severity: if a broader spectrum of mutations is selected in tumors, the somatic mutation rate is effectively higher and more tumors grow.


Assuntos
Polipose Adenomatosa do Colo/genética , Neoplasias Colorretais/genética , Genes APC/genética , Mutação em Linhagem Germinativa/genética , Modelos Genéticos , Mutação/genética , Adenoma/genética , Adenoma/patologia , Polipose Adenomatosa do Colo/patologia , Alelos , Sequência de Bases , Códon/genética , Neoplasias Colorretais/patologia , Análise Mutacional de DNA , Éxons/genética , Saúde da Família , Fibromatose Agressiva/genética , Fibromatose Agressiva/patologia , Mutação da Fase de Leitura/genética , Deleção de Genes , Frequência do Gene , Humanos
7.
Folia Primatol (Basel) ; 70(1): 1-7, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10050061

RESUMO

The diet of Saguinus midas is characterised by analysis of stomach contents samples on an annual and seasonal basis. The diet comprises significant proportions of both fruit and insects all year round, although fruit use shows important seasonal variations. The tamarins reduce their use of fruit resources during the peak fruiting season and instead exploit increased opportunities for insectivory. This is suggested to be a response to differences in gross fruit availability as a function of both fruiting patterns and the presence of competitors for the available fruit resources.


Assuntos
Dieta/veterinária , Frutas , Insetos , Saguinus/fisiologia , Animais , Peso Corporal , Guiana Francesa , Conteúdo Gastrointestinal/química , Estações do Ano , Estômago
8.
Proc Natl Acad Sci U S A ; 95(18): 10722-7, 1998 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-9724771

RESUMO

Classical familial adenomatous polyposis (FAP) is a high-penetrance autosomal dominant disease that predisposes to hundreds or thousands of colorectal adenomas and carcinoma and that results from truncating mutations in the APC gene. A variant of FAP is attenuated adenomatous polyposis coli, which results from germ-line mutations in the 5' and 3' regions of the APC gene. Attenuated adenomatous polyposis coli patients have "multiple" colorectal adenomas (typically fewer than 100) without the florid phenotype of classical FAP. Another group of patients with multiple adenomas has no mutations in the APC gene, and their phenotype probably results from variation at a locus, or loci, elsewhere in the genome. Recently, however, a missense variant of APC (I1307K) was described that confers an increased risk of colorectal tumors, including multiple adenomas, in Ashkenazim. We have studied a set of 164 patients with multiple colorectal adenomas and/or carcinoma and analyzed codons 1263-1377 (exon 15G) of the APC gene for germ-line variants. Three patients with the I1307K allele were detected, each of Ashkenazi descent. Four patients had a germ-line E1317Q missense variant of APC that was not present in controls; one of these individuals had an unusually large number of metaplastic polyps of the colorectum. There is increasing evidence that there exist germ-line variants of the APC gene that predispose to the development of multiple colorectal adenomas and carcinoma, but without the florid phenotype of classical FAP, and possibly with importance for colorectal cancer risk in the general population.


Assuntos
Neoplasias Colorretais/genética , Genes APC , Mutação , Adulto , Idoso , Sequência de Bases , Neoplasias Colorretais/etnologia , Primers do DNA , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Polimorfismo Conformacional de Fita Simples
11.
Plant Cell Rep ; 14(10): 620-5, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24194308

RESUMO

A procedure for the regeneration of fertile transgenic Chinese cabbage (Brassica campestris ssp. pekinensis cv. 'Spring Flavor') is presented in this report. The protocol is based on infection of cotyledon explants of 5-d-old seedlings with an Agrobacterium tumefaciens strain LBA4404 carrying a disarmed binary vector pTOK/BKS-1. The T-DNA region of this binary vector contains the nopaline synthase/neomycin phosphotransferase II (nptII) chimeric gene for kanamycin resistance and the cauliflower mosaic virus 35S/coat protein gene of tobacco mosaic virus L (TMV-L) chimeric gene. After co-cultivation for 48 h, the cotyledonary petioles were placed on shoot induction media containing 15 mg/L kanamycin sulfate. Shoot induction was continued for 3-4 weeks, then subcultured once and after 2 weeks the shoots were transferred to root induction medium. After 1 week 8 putatively transformed plantlets from 200 cotyledon explants were obtained and transferred to greenhouse. Six of them grew to maturity, produced normal flowers and set seeds. Polymerase chain reaction and Southern blot hybridization analyses confirmed the introduction of the T-DNA into the Chinese cabbage genome. Further, Western blot analysis using polyclonal TMV antiserum showed most of the regenerants (5 out of 6) expressed TMV coat protein gene. Stable inheritance of the inserted clone was investigated in the next generation.

12.
J Med Genet ; 31(11): 888-90, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7853377

RESUMO

Familial adenomatous polyposis is an autosomal dominantly inherited disorder. Mutation studies in the corresponding gene (APC) may provide information for predictive tests for persons at risk in affected families. We report here a new mutation in exon 6 (codon 233) of the APC gene and clinical data in a large family with late onset of the disease in most affected persons.


Assuntos
Polipose Adenomatosa do Colo/genética , Genes APC , Mutação , Adolescente , Adulto , Idade de Início , Sequência de Bases , Haplótipos , Humanos , Dados de Sequência Molecular , Linhagem , Reação em Cadeia da Polimerase , Polimorfismo Genético
13.
Gut ; 35(11): 1622-3, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7828985

RESUMO

The phenotypic expression in familial adenomatous polyposis (FAP) is variable. This study compares the phenotype of 27 patients with an identical 5 base pair (bp) deletion at codon 1309 with a group of 61 matched patients with FAP where knowledge of specific mutations is not available and with seven other different mutations in 24 subjects. Patients with the codon 1309 deletion have significantly more colorectal polyps at the time of colectomy than age and sex matched FAP controls (p = 0.0001). The median number of polyps in colectomy specimens of patients with the deletion at codon 1309 was 4000 (interquartile (IQ) range 3000-4875), compared with 600 (IQ range 488-1400) in the matched controls. Mutations at codon 1323, 1407, and 233 were also associated with large numbers of polyps. Desmoid disease and extracolonic cancers were more common with the mutation at codon 1309 (p = 0.003). In conclusion, there may be a correlation between a specific germline mutation and the number of large bowel polyps. There is residual heterogeneity in phenotypic expression, however, and this may result from the influence of other genes, specific environmental factors or chance.


Assuntos
Polipose Adenomatosa do Colo/genética , Genes APC/genética , Mutação , Polipose Adenomatosa do Colo/patologia , Colo/patologia , Análise Mutacional de DNA , Fibromatose Agressiva/genética , Deleção de Genes , Humanos , Fenótipo
14.
Vet Rec ; 126(2): 44-5, 1990 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-2301117
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