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1.
Neuroimage ; 209: 116477, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31874257

RESUMO

Alterations induced by prenatal exposure to nicotine have been observed in experimental (rodent) studies. While numerous developmental outcomes have been associated with prenatal exposure to maternal cigarette smoking (PEMCS) in humans, the possible relation with brain structure is less clear. Here we sought to elucidate the relation between PEMCS and structural properties of human corpus callosum in adolescence and early adulthood in a total of 1,747 youth. We deployed three community-based cohorts of 446 (age 25-27 years, 46% exposed), 934 (age 12-18 years, 47% exposed) and 367 individuals (age 18-21 years, 9% exposed). A mega-analysis revealed lower mean diffusivity in the callosal segments of exposed males. We speculate that prenatal exposure to maternal cigarette smoking disrupts the early programming of callosal structure and increases the relative portion of small-diameter fibres.


Assuntos
Fumar Cigarros , Corpo Caloso , Imageamento por Ressonância Magnética , Neuroimagem , Efeitos Tardios da Exposição Pré-Natal , Adolescente , Adulto , Criança , Fumar Cigarros/efeitos adversos , Estudos de Coortes , Corpo Caloso/diagnóstico por imagem , Corpo Caloso/embriologia , Corpo Caloso/patologia , Imagem de Tensor de Difusão , Inglaterra , Feminino , Finlândia , Humanos , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/diagnóstico por imagem , Efeitos Tardios da Exposição Pré-Natal/patologia , Quebeque , Fatores Sexuais , Adulto Jovem
2.
Neuroimage ; 152: 108-118, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28254453

RESUMO

A number of structural properties of white matter can be assessed in vivo using multimodal magnetic resonance imaging (MRI). We measured profiles of R1 and R2 relaxation rates, myelin water fraction (MWF) and diffusion tensor measures (fractional anisotropy [FA], mean diffusivity [MD]) across the mid-sagittal section of the corpus callosum in two samples of young individuals. In Part 1, we compared histology-derived axon diameter (Aboitiz et al., 1992) to MRI measures obtained in 402 young men (19.55 ± 0.84 years) recruited from the Avon Longitudinal Study on Parents and Children. In Part 2, we examined sex differences in FA, MD and magnetization transfer ratio (MTR) across the corpus callosum in 433 young (26.50 ± 0.51 years) men and women recruited from the Northern Finland Birth Cohort 1986. We found that R1, R2, and MWF follow the anterior-to-posterior profile of small-axon density. Sex differences in mean MTR were similar across the corpus callosum (males > females) while these in FA differed by the callosal segment (Body: M>F; Splenium: F>M). We suggest that the values of R1, R2 and MWF are driven by high surface area of myelin in regions with high density of "small axons".


Assuntos
Corpo Caloso/anatomia & histologia , Corpo Caloso/fisiologia , Caracteres Sexuais , Adolescente , Adulto , Anisotropia , Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Feminino , Humanos , Masculino , Substância Branca/anatomia & histologia , Substância Branca/fisiologia , Adulto Jovem
3.
Gene Ther ; 22(10): 802-10, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26005860

RESUMO

Prostate cancer is the most common cancer in men of the western world. To date, no effective treatment exists for metastatic prostate cancer and consequently, there is an urgent need to develop new and improved therapeutics. In recent years, the therapeutic potential of RNA interference (RNAi) has been extensively explored in a wide range of diseases including prostate cancer using numerous gene delivery vectors. The aims of this study were to investigate the ability of a non-viral modified cyclodextrin (CD) vector to deliver siRNA to the highly metastatic PC-3 prostate cancer cell line, to quantify the resulting knockdown of the two target genes (RelA and SRF) and to study the effects of the silencing on metastasis. Data from a Matrigel in vitro invasion assay indicated that the silencing of the target genes achieved by the CD vector resulted in significant reductions (P=0.0001) in the metastatic potential of these cells. As the silencing of these target genes was shown not to have a negative impact on cell viability, we hypothesise that the mechanism of invasion inhibition is due, in part, to the significant reduction observed (P⩽0.0001) in the level of pro-inflammatory cytokine, MMP9, which is known to be implicated in the metastasis of prostate cancer.


Assuntos
Ciclodextrinas , Vetores Genéticos , NF-kappa B/genética , Neoplasias da Próstata/terapia , RNA Interferente Pequeno/administração & dosagem , Fator de Resposta Sérica/genética , Fator de Transcrição RelA/genética , Linhagem Celular Tumoral , Humanos , Masculino , Invasividade Neoplásica/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Interferência de RNA , RNA Interferente Pequeno/genética
4.
Clin Radiol ; 67(3): 239-43, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21978818

RESUMO

AIM: To establish how often off-label device and drug use occurs in interventional radiology (IR) in a UK tertiary referral hospital and consider the wider implications for the interventional radiologist. MATERIALS AND METHODS: Prospective data were collected during interventional procedures for 1 working week in a university hospital. Out-of-hours procedures and procedures outside the department were excluded. Operators were asked to record the drugs and devices used, the indication, and method of use. The instructions for use/summary of product characteristics were then studied for each device/drug used to assess if the use was on or off-label. RESULTS: During the study period 52 cases were performed and data were available on 26 cases (50%). In 22 of the 26 cases (84%) there was evidence of off-label use of devices or drugs. Off-label use of drugs included treatment of venous malformations with Fibrovein(©) (sodium tetradecyl sulphate), which is licensed for the treatment of varicose veins in the leg, and intra-arterial injection of heparin, which is licensed for intravenous and subcutaneous use. Off-label device use included placing vascular sheaths in the urinary tract, using angiographic catheters to guide wires in the urinary tract, using sheaths for thrombosuction, reshaping of the tip of most guidewires, and using angioplasty balloons to dislodge the arterial plug at fistula thrombectomy. CONCLUSION: Off-label device and drugs use is common in a UK tertiary hospital IR department and literature suggests this is common in the wider IR community. There are important clinical and legal implications for off-label use for patients and physicians.


Assuntos
Equipamentos e Provisões/estatística & dados numéricos , Uso Off-Label/estatística & dados numéricos , Radiologia Intervencionista/métodos , Hospitais Universitários , Humanos , Estudos Prospectivos , Radiologia Intervencionista/instrumentação , Radiologia Intervencionista/estatística & dados numéricos , Reino Unido
5.
J Fish Biol ; 75(10): 2872-4, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20738534

RESUMO

The topic of fish welfare in the context of commercial fisheries is a difficult one. From traditionally anthropocentric or human-centred perspectives, fishes are simply objects for humans to use as they see fit. When it is argued that anthropocentrism is arbitrary, it may appear that a strong animal rights position is the only recourse, with the result that humans ought not to use animals in the first place, if it is at all possible. It can be argued that both positions fail to view human beings as part of the natural world. If human beings are viewed as part of the world from which they live, then it has to be asked what it means to be respectful of the animals which humans use and from which they live. From this perspective, concern for the welfare of the fishes humans eat is simply what should be expected from humans as good citizens in the community of living creatures.


Assuntos
Direitos dos Animais , Bem-Estar do Animal/ética , Pesqueiros/ética , Peixes , Animais , Humanos
6.
J Clin Epidemiol ; 61(9): 951-7, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18495425

RESUMO

OBJECTIVE: To compare implications of Angina Pectoris (AP) and Intermittent Claudication (IC) as indicators of clinical atherosclerosis in other vascular territories. STUDY DESIGN AND SETTING: Prospective cohort study of cardiovascular disease (CVD) in 5,209 men and women of Framingham, MA, aged 28-62 years at enrollment in 1948-1951, who received biennial examinations during the first 36 years of follow-up. Comparative 10-year incidence of subsequent atherosclerotic CVD in participants with IC and AP relative to a reference sample free of CVD was determined. RESULTS: On follow-up, 95 CVD events occurred in 186 participants with IC and 206 of 413 with AP. After age, sex, and risk-factor adjustment, the proportion acquiring other CVD was 34.0% for IC and 43.4% for AP. Relative to the reference sample, those with IC had a 2.73-fold higher age and sex-adjusted 10-year hazard of CVD (95% CI 2.21, 3.38) and for AP was 3.17 (95% CI 2.73, 3.69). CVD hazard ratios remained more elevated for AP and statistically significant after standard risk factor adjustment. Risk factors accounted for more of the excess CVD risk associated with IC (34.8%) than AP (9.5%). CONCLUSION: AP is as useful as IC as a hallmark of diffuse atherosclerotic CVD and an indication for comprehensive preventive measures.


Assuntos
Angina Pectoris/diagnóstico , Aterosclerose/diagnóstico , Claudicação Intermitente/diagnóstico , Adulto , Angina Pectoris/epidemiologia , Aterosclerose/epidemiologia , Feminino , Humanos , Claudicação Intermitente/epidemiologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Esfigmomanômetros/estatística & dados numéricos
7.
Clin Genet ; 70(4): 336-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16965328

RESUMO

Rett syndrome is a severe neurodevelopmental disorder that is caused by mutations in the X-linked gene, methyl-CpG binding protein 2 (MECP2). The majority of cases are sporadic, but rarely germline mosaicism can lead to familial cases. Here, we report the first case where germline mosaicism for a MECP2 mutation has been shown in a man. He has two affected daughters who are half sisters, and both have the c.808delC mutation. We show that this mutation is present at a low level in DNA extracted from the patient's semen. This case has implications for genetic counseling, and pre-natal testing should be offered for the partners of men who have a daughter with Rett syndrome.


Assuntos
Mutação em Linhagem Germinativa , Proteína 2 de Ligação a Metil-CpG/genética , Mosaicismo , Síndrome de Rett/genética , Sequência de Bases , Humanos , Masculino , Dados de Sequência Molecular , Núcleo Familiar , Linhagem
9.
J Intellect Disabil Res ; 50(Pt 5): 386-94, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16629931

RESUMO

BACKGROUND: People with useful speech after regression constitute a distinct group of those with mutation-positive Rett disorder, 6% (20/331) reported among mutation-positive people in the British Survey. We aimed to determine the physical, mental and genetic characteristics of this group and to gain insight into their experience of Rett syndrome. METHODS: Clinical and molecular data for people with Rett, aged 10 or more years at follow-up (the study group, n = 13), with the ability to converse and a MECP2 mutation are presented. They were compared with an age-matched control group (n = 110), who could not converse and had a pathogenic MECP2 mutation. RESULTS: The study group differed significantly from the control group with regard to their disease severity (P < 0.001); feeding difficulty scores (P < 0.001); health scores (P < 0.001); epilepsy (P < 0.001); head circumference (P < 0.004); age at onset of the regression period (P < 0.001) (six in the study group did not regress) and mutation frequency (C-terminal deletions P = 0.014, R133C P < 0.006). The results indicate that favourable skewing of X-inactivation is only present in a small proportion of mild cases. Speech was fragmented with a soft, breathless quality, and all but two had obviously irregular breathing. One person with an R168X mutation preferred signing to speech. All enjoyed interpersonal contact, showing affection and preferring people to objects, clearly distinguishing the condition from autism. Most were habitually anxious. Music was a source of pleasure and relaxation also providing a valuable educational asset. Even in these most able cases, understanding was severely restricted in most and little initiative was shown. CONCLUSIONS: While the Rett profile is present in these people they are commonly not classic, and the presence of speech, good head growth and lack of regression may lead to missed diagnoses. A strong association was demonstrated between this milder form of the disease and R133C and C-terminal deletions.


Assuntos
Proteína 2 de Ligação a Metil-CpG/genética , Síndrome de Rett/genética , Síndrome de Rett/psicologia , Fala , Adulto , Idade de Início , Arte , Ingestão de Alimentos , Epilepsia/complicações , Seguimentos , Nível de Saúde , Humanos , Mutação , Fenótipo , Respiração , Síndrome de Rett/complicações , Índice de Gravidade de Doença , Redação
10.
J Med Genet ; 43(5): 451-6, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16183801

RESUMO

MECP2 mutations are identifiable in approximately 80% of classic Rett syndrome (RTT), but less frequently in atypical RTT. We recruited 110 patients who fulfilled the diagnostic criteria for Rett syndrome and were referred to Cardiff for molecular analysis, but in whom an MECP2 mutation was not identifiable. Dosage analysis of MECP2 was carried out using multiplex ligation dependent probe amplification or quantitative fluorescent PCR. Large deletions were identified in 37.8% (14/37) of classic and 7.5% (4/53) of atypical RTT patients. Most large deletions contained a breakpoint in the deletion prone region of exon 4. The clinical phenotype was ascertained in all 18 of the deleted cases and in four further cases with large deletions identified in Goettingen. Five patients with large deletions had additional congenital anomalies, which was significantly more than in RTT patients with other MECP2 mutations (2/193; p<0.0001). Quantitative analysis should be included in molecular diagnostic strategies in both classic and atypical RTT.


Assuntos
Aberrações Cromossômicas , Proteína 2 de Ligação a Metil-CpG/genética , Síndrome de Rett/diagnóstico , Síndrome de Rett/genética , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Análise Mutacional de DNA , Feminino , Dosagem de Genes , Testes Genéticos , Humanos
11.
Bone Marrow Transplant ; 35(3): 283-90, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15531894

RESUMO

Allogeneic bone marrow transplantation (BMT) with marrow ablative conditioning is the treatment of choice for haematopoietic malignancies. The use of nonmyeloablative stem cell transplants has allowed the treatment of patients previously ineligible for BMT because of age or other disease. These reduced conditioning regimes allow the persistence initially of some recipient cells in the blood and bone marrow (haematopoietic chimaerism). Monitoring of the relative proportion of donor and recipient cells is required to assess the success of the procedure, to predict subsequent rejection or impending relapse and to guide the use of donor lymphocyte infusions. We present a quantitative real-time PCR approach for the measurement of haematopoietic chimaerism using the TaqMan. This approach exploits the presence of single-nucleotide polymorphisms (SNPs) to distinguish cells of patient or donor origin. We have designed and validated a panel of seven allele-specific probes to quantify the contribution of patient and donor cells in the haematopoietic population from 12 patient and donor pairs. We have compared the performance of this approach with an existing method and proved it to be superior in both accuracy and sensitivity. The use of more sensitive and accurate techniques permits earlier intervention for improved clinical outcome.


Assuntos
Reação em Cadeia da Polimerase/métodos , Quimeras de Transplante/genética , Adulto , Células Sanguíneas , Células da Medula Óssea , Sondas de DNA , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Transplante Homólogo
12.
Br J Surg ; 91(8): 1020-6, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15286965

RESUMO

BACKGROUND: The aim was to evaluate the outcome of major resection for chronic pancreatitis in patients with and without vascular involvement. METHODS: Of 250 patients with severe chronic pancreatitis referred between 1996 and 2003, 112 underwent pancreatic resection. The outcome of 17 patients (15.2 per cent) who had major vascular involvement was compared with that of patients without vascular involvement. RESULTS: The 95 patients without vascular involvement had resections comprising Beger's operation (39 patients), Kausch-Whipple pancreatoduodenectomy (28), total pancreatectomy (25) and left pancreatectomy (three). Twenty-five major vessels were involved in the remaining 17 patients. One or more major veins were occluded and/or compressed producing generalized or segmental portal hypertension, and three patients also had major arterial involvement. Surgery in these patients comprised Beger's operation (eight), total pancreatectomy (five), Kausch-Whipple pancreatoduodenectomy (two) and left pancreatectomy (two). Perioperative mortality rates were significantly different between the groups (two of 95 versus three of 17 respectively; P = 0.024). There were similar and significant improvements in long-term outcomes in both groups. CONCLUSION: Resection for severe chronic pancreatitis in patients with vascular complications is hazardous and is associated with an increased mortality rate. Vascular assessment should be included in the routine follow-up of patients with chronic pancreatitis, to enable early identification of those likely to develop vascular involvement and prompt surgical intervention.


Assuntos
Pâncreas/irrigação sanguínea , Pancreatite/cirurgia , Adolescente , Adulto , Idoso , Doença Crônica , Feminino , Humanos , Isquemia/etiologia , Tempo de Internação , Fígado/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Hemorragia Pós-Operatória/etiologia , Estudos Prospectivos , Reoperação/estatística & dados numéricos , Trombose/etiologia , Resultado do Tratamento
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 60(8-9): 2029-33, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15248982

RESUMO

The role of Antarctic epilithic lichens in the primary colonization of rocks and in the formation of soils is receiving attention because of the production of the stress-protective biochemicals needed to combat radiation, desiccation and extremes of temperature. Raman microscopy has been used here to study the encrustations produced at the interface between the rock substratum and Buellia spp. lichen thalli; in addition to whewellite, calcium oxalate monohydrate, the presence of weddellite, the metastable dihydrate form, was confirmed in the encrustations. An unusual pigmentation of the rock surface found on detachment of the lichen growths is identified as beta-carotene from its characteristic Raman bands at 1525, 1191, 1157 and 1003 cm(-1); normally, beta-carotene, which has been identified as a UV-radiation protectant, is found at the exposed upper surface of the biological organism. The interface between the detached lichen thalli and the rock also contains whewellite as the sole biomineralization product--which suggests a possible strategy for the formulation of weddelite in the growing Buellia spp. colony as an anti-desiccant.


Assuntos
Líquens/química , Regiões Antárticas , Meio Ambiente , Análise de Fourier , Líquens/efeitos da radiação , Microscopia/métodos , Protetores contra Radiação/análise , Análise Espectral Raman , Raios Ultravioleta/efeitos adversos , beta Caroteno/análise
16.
J Comp Physiol B ; 173(5): 419-27, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12783264

RESUMO

Glutamine synthetase, an enzyme generally associated with ammonia detoxication in the vertebrate brain and with hepatic nitrogen turnover in mammals, shows substantial activities in the gastrointestinal tract of teleostean fishes. Enzyme activity is highest in the central area of the stomach and reveals a distinct distribution pattern in stomach and along the intestine of tilapia (Oreochromis niloticus), rainbow trout (Oncorhynchus mykiss) and copper rockfish (Sebastes caurinus). In all three species, intestinal activity peaks in the distal region of the intestine. The brain contains the highest titre of the enzyme (46 U g(-1) in tilapia brain versus 15 U g(-1) in tilapia stomach), but because of the relative mass of the stomach, the largest glutamine synthetase pool in tilapia body appears to be localized in the stomach. Activities in white and red muscle are very modest at 0.1% of the brain. Independent of distribution, peak activities of glutamine synthetase in selected areas of tilapia stomach and intestine are significantly (two- to fourfold) increased after a 5-day treatment with an intraperitoneal cortisol deposit. Cortisol also increases glutamine synthetase activity in tilapia liver, white and red muscle, while activities in brain remain unaffected. We cloned and sequenced the predominant transcript of tilapia stomach glutamine synthetase (about 1.9 kb), encoding a 371-amino acid peptide. The open reading frame shows considerable identity with glutamine synthetase in toadfish (92% at peptide level, 87% at nucleotide level), but possesses a longer 3'-untranslated region than the toadfish. The tilapia glutamine synthetase mRNA contains a remnant of a putative mitochondrial leader sequence, but without a conserved second site for initiation of translation. We also find evidence for additional transcripts of glutamine synthetase in tilapia, suggesting multiple genes. Finally, we present evidence for similar abundance of glutamine synthetase transcripts in all regions of rockfish intestine. The physiological significance of the presence of glutamine synthetase in teleostean intestine is discussed.


Assuntos
Ativação Enzimática/efeitos dos fármacos , Trato Gastrointestinal/enzimologia , Glutamato-Amônia Ligase/genética , Glutamato-Amônia Ligase/metabolismo , Hidrocortisona/farmacologia , Tilápia/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Encéfalo/enzimologia , Primers do DNA , DNA Complementar/genética , Hidrocortisona/sangue , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Tilápia/genética
17.
Dig Surg ; 20(4): 270-7, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12748429

RESUMO

INTRODUCTION: Open surgery for pancreatic necrosis is associated with considerable morbidity and mortality. We report the results of a recently developed minimally invasive technique that we adopted in 1998. METHODS: A descriptive explanation of the approach is given together with the results of a retrospective analysis of patients who underwent a minimally invasive retroperitoneal pancreatic necrosectomy (MIRP) between August 1998 and April 2002. PATIENTS: There were 24 patients with a median (range) age of 61 (29-75) years. The initial median (range) APACHE II score was 8 (2-21). All patients had infected pancreatic necrosis with at least 50% pancreatic necrosis. In three patients it was not possible to complete the first MIRP because of technical reasons. RESULTS: A total of 88 procedures were performed with a median (range) of 4 (0-8) per patient. Twenty-one (88%) patients developed 36 complications during the course of their illness. Five patients required an additional open procedure: 2 for subsequent distant collections, 2 for bleeding and 1 for persisting sepsis and a distant abscess. Six (25%) patients who had MIRP died. The median (range) post-operative hospital stay was 51 (5-200) days. CONCLUSIONS: MIRP is a new technique that has shown promising results, and could be preferable to open pancreatic necrosectomy in selected patients. However, unresolved issues remain to be overcome and the exact role of MIRP in the management of pancreatic necrosis has yet to be defined.


Assuntos
Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Pancreatectomia/métodos , Pancreatite Necrosante Aguda/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação , Espaço Retroperitoneal , Estudos Retrospectivos , Resultado do Tratamento
18.
FEMS Microbiol Ecol ; 45(1): 59-70, 2003 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-19719607

RESUMO

Abstract The biodiversity of the pelagic bacterioplankton community of a maritime Antarctic freshwater lake was examined by cultivation-dependent and cultivation-independent techniques to determine predominant bacterioplankton populations present. The culture-dependent techniques used were direct culture and observation, polymerase chain reaction amplification of 16S rRNA gene fragments, restriction fragment length polymorphism (RFLP) analysis followed by selective sequencing and fatty acid methyl ester analysis. The culture-independent techniques used were 16S ribosomal DNA gene cloning, RFLP analysis and sequencing, in situ hybridisation with group-specific, fluorescently labelled oligonucleotide probes and cloning and sequencing of dominant denaturing gradient gel electrophoresis products. Significant differences occurred between the results obtained with each method. However, sufficient overlap existed between the different methods to identify potentially significant groups. At least six different bacterial divisions including 24 genera were identified using culture-dependent techniques, and eight different bacterial divisions, including 23 genera, were identified using culture-independent techniques. Only five genera, Corynebacterium, Cytophaga, Flavobacterium, Janthinobacterium and Pseudomonas, could be identified using both sets of techniques, which represented four different bacterial divisions. Significantly for Antarctic freshwater lakes, pigment production is found within members of each of these genera. This work illustrates the importance of a comprehensive polyphasic approach in the analysis of lake bacterioplankton, and supports the ecological relevance of results obtained in earlier entirely culture-based studies.

19.
Diabetologia ; 45(6): 899-904, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12107735

RESUMO

AIMS/HYPOTHESIS: Genotype could influence vascular function. In some populations, Calpain 10 gene polymorphisms increase susceptibility to diabetes or insulin resistance. Alterations in microvascular function could contribute to insulin resistance. This study investigated whether polymorphisms in the Calpain-10 gene influence microvascular function. METHODS: Skin maximum microvascular hyperaemia to local heating on the dorsum of the foot (30 min at 43 degrees C) was measured by Laser Doppler Fluximetry in 37 healthy volunteers. All were normoglycaemic according to World Health Organisation criteria, normotensive and not on any medication. Four polymorphisms in the calpain-10 gene were typed: SNP-44, SNP-43, SNP-19, SNP-63. The SNP common to all the described high risk haplotypes is the G-allele at SNP-43. This intron 3 polymorphism appears to influence gene expression. Microvascular function was examined in relation to polymorphisms at this site alone as well as the effects of the known extended high risk haplotypes using the SNP's above. RESULTS: Maximum microvascular hyperaemia was increased in the 21 subjects with G/G genotypes at SNP-43 compared to the combined group of subjects ( G/ A genotype at SNP-43 ( n=12) + A/ A genotype at SNP-43 ( n=4)), and the minimum microvascular resistance was reduced 49.4 (39.6-94.2) vs 67.5 (39.1-107.3) mmHg/V, p=0.007). Haplotype analysis of the hyperaemic response revealed no significant differences between haplotypes. The two groups did not differ in terms of anthropometric measures, blood pressure, insulin resistance or glucose. CONCLUSIONS/INTERPRETATION: The polymorphism that confers susceptibility to Type II (non-insulin-dependent) diabetes mellitus in some populations is associated in United Kingdom Caucasians with enhanced microvascular function in the presence of normoglycaemia.


Assuntos
Calpaína/genética , Regulação Enzimológica da Expressão Gênica , Microcirculação/fisiologia , Polimorfismo de Nucleotídeo Único , Pele/irrigação sanguínea , Adulto , Glicemia/metabolismo , Pressão Sanguínea , Inglaterra , Feminino , Haplótipos , Humanos , Resistência à Insulina/fisiologia , Íntrons , Fluxometria por Laser-Doppler , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Valores de Referência , Resistência Vascular , População Branca
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