Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 67
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Eur J Neurol ; 28(1): 238-247, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920964

RESUMO

BACKGROUND AND PURPOSE: Recent observations linked coronavirus disease 2019 (COVID-19) to thromboembolic complications possibly mediated by increased blood coagulability and inflammatory endothelial impairment. We aimed to define the risk of acute stroke in patients with severe and non-severe COVID-19. METHODS: We performed an observational, multicenter cohort study in four participating hospitals in Saxony, Germany to characterize consecutive patients with laboratory-confirmed COVID-19 who experienced acute stroke during hospitalization. Furthermore, we conducted a systematic review using PubMed/MEDLINE, Embase, Cochrane Library and bibliographies of identified papers following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines including data from observational studies of acute stroke in COVID-19 patients. Data were extracted by two independent reviewers and pooled with multicenter data to calculate risk ratios (RRs) and 95% confidence intervals (95% CIs) for acute stroke related to COVID-19 severity using a random-effects model. Between-study heterogeneity was assessed using Cochran's Q and I2 statistics. International Prospective Register of Systematic Reviews registration number: CRD42020187194. RESULTS: Of 165 patients hospitalized for COVID-19 (49.1% males, median age = 67 years [57-79 years], 72.1% severe or critical) included in the multicenter study, overall stroke rate was 4.2% (95% CI: 1.9-8.7). Systematic literature search identified two observational studies involving 576 patients that were eligible for meta-analysis. Amongst 741 pooled COVID-19 patients, overall stroke rate was 2.9% (95% CI: 1.9-4.5). Risk of acute stroke was increased for patients with severe compared to non-severe COVID-19 (RR = 4.18, 95% CI: 1.7-10.25; P = 0.002) with no evidence of heterogeneity (I2  = 0%, P = 0.82). CONCLUSIONS: Synthesized analysis of data from our multicenter study and previously published cohorts indicates that severity of COVID-19 is associated with an increased risk of acute stroke.


Assuntos
COVID-19/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Idoso , Idoso de 80 Anos ou mais , COVID-19/complicações , Estudos de Coortes , Feminino , Alemanha/epidemiologia , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Acidente Vascular Cerebral/complicações , Tromboembolia/epidemiologia
2.
J Eur Acad Dermatol Venereol ; 29(5): 835-41, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25376665

RESUMO

Bariatric surgery has become a standard option in morbid obesity for patients not responding to conventional treatment. A major and stable weight loss can be achieved. Since obesity and weight loss may affect skin diseases, we performed this review to analyse the impact of bariatric surgery on a number of skin diseases. We categorized the skin diseases into three main groups: (i) diseases with a possible benefit from bariatric surgery, (ii) diseases that may develop after bariatric surgery and (iii) diseases that may persist. We hope that dermatologists will achieve an updated knowledge of benefits and possible hazards of this type of surgically induced weight loss.


Assuntos
Cirurgia Bariátrica , Obesidade Mórbida/cirurgia , Dermatopatias/etiologia , Progressão da Doença , Humanos , Obesidade Mórbida/complicações , Remissão Espontânea , Índice de Gravidade de Doença
3.
Int J Obes (Lond) ; 38(1): 120-5, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23670221

RESUMO

OBJECTIVE: We hypothesized that genes within recently identified loci associated with waist-hip ratio (WHR) exhibit fat depot-specific mRNA expression, which correlates with obesity-related traits. METHODS: Adipose tissue (AT) mRNA expression of 6 genes (TBX15/WARS2, STAB1, PIGC, ZNRF3 and GRB14) within these loci showing coincident cis-expression quantitative trait loci was measured in 222 paired samples of human visceral (vis) and subcutaneous (sc) AT. The relationship of mRNA expression levels with obesity-related quantitative traits was assessed by Pearson's correlation analyses. Multivariate linear relationships were assessed by generalized linear regression models. RESULTS: Whereas only PIGC, ZNFR3 and STAB1 mRNA expression in sc AT correlated nominally with WHR (P<0.05, adjusted for age and sex), mRNA expression of all studied genes in at least one of the fat depots correlated significantly with vis and/or sc fat area (P ranging from 0.05 to 4.0 × 10(6), adjusted for age and sex). Consistently, the transcript levels of WARS, PIGC and GRB14 were nominally associated with body mass index (BMI) (P ranging from 0.02 to 9.2 × 10(5), adjusted for age and sex). Moreover, independent of sex, obesity and diabetes status, differential expression between vis and sc AT was observed for all tested genes (P<0.01). Finally, the rs10195252 T-allele was nominally associated with increased GRB14 sc mRNA expression (P=0.025 after adjusting for age, sex and BMI). CONCLUSIONS: Our data including the inter-depot variability of mRNA expression suggests that genes within the WHR-associated loci might be involved in the regulation of fat distribution.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Tecido Adiposo/metabolismo , Composição Corporal , Distribuição da Gordura Corporal , Moléculas de Adesão Celular Neuronais/metabolismo , Hexosiltransferases/metabolismo , Proteínas de Membrana/metabolismo , Obesidade/metabolismo , Receptores de Retorno de Linfócitos/metabolismo , Gordura Subcutânea/metabolismo , Proteínas com Domínio T/metabolismo , Triptofano-tRNA Ligase/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Adulto , Índice de Massa Corporal , Moléculas de Adesão Celular Neuronais/genética , Feminino , Genótipo , Hexosiltransferases/genética , Humanos , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Fenótipo , Polimorfismo de Nucleotídeo Único , RNA Mensageiro/metabolismo , Receptores de Retorno de Linfócitos/genética , Proteínas com Domínio T/genética , Triptofano-tRNA Ligase/genética , Ubiquitina-Proteína Ligases/genética , Relação Cintura-Quadril
4.
Pharmacogenomics J ; 14(3): 201-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24365785

RESUMO

Bariatric surgery is a well-established approach to improve metabolic disease in morbidly obese patients with high cardiovascular risk. The post-operative normalization of lipid metabolism has a central role in the prevention of future cardiovascular events. The aim of the present study therefore was to characterize changes of plasma lipidomic patterns, consisting of 229 lipid species of 13 lipid classes, 3 months after Roux-en-Y gastric bypass (RYGB) in morbidly obese patients with and without diabetes. RYGB resulted in a 15-32% decrease of body mass index, which was associated with a significant reduction of total cholesterol (TC, -28.3%; P=0.02), LDL-cholesterol (LDL-C, -26.8%; P=0.03) and triglycerides (TGs, -63.0%; P=0.05) measured by routine clinical chemistry. HDL-cholesterol remained unchanged. The effect of RYGB on the plasma lipidomic profile was characterized by significant decreases of 87 lipid species from triacylglycerides (TAGs), cholesterol esters (CholEs), lysophosphatidylcholines (LPCs), phosphatidylcholines (PCs), phosphatidylethanolamine ethers (PEOs), phosphatidylinositols (PIs) and ceramides (Cers). The total of plasma lipid components exhibited a substantial decline of 32.6% and 66 lipid species showed a decrease by over 50%. A direct correlation with HbA1C values could be demonstrated for 24 individual lipid species (10 TAG, three CholE, two LPC, one lysophosphatidylcholine ethers (LPCO) (LPC ether), one PC, two phosphatidylcholine ethers (PCO) and five Cer). Notably, two lipid species (TAG 58:5 and PEO 40:5) were inversely correlated with HbA1C. LPCO, as single whole lipid class, was directly related to HbA1C. These data indicate that RYGB-induced modulation of lipidomic profiles provides important information about post-operative metabolic adaptations and might substantially contribute to improvements of glycemic control. These striking changes in the human plasma lipidome may explain acute, weight independent and long-term effects of RYGB on the cardiovascular system, mental status and immune regulation.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Derivação Gástrica , Lipídeos/sangue , Obesidade Mórbida/cirurgia , Cromatografia Líquida de Alta Pressão , Diabetes Mellitus Tipo 2/complicações , Humanos , Lipídeos/classificação , Obesidade Mórbida/sangue , Obesidade Mórbida/complicações
5.
Pharmacogenomics J ; 13(6): 514-22, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23032991

RESUMO

Roux-en-Y gastric bypass (RYGB) has become a prominent therapeutic option for long-term treatment of morbid obesity and type 2 diabetes mellitus (T2D). Cross talk and pathogenetic consequences of RYGB-induced profound effects on metabolism and gut microbiome are poorly understood. The aim of the present study therefore was to characterize intra-individual changes of gut microbial composition before and 3 months after RYGB by metagenomic sequencing in morbidly obese patients (body mass index (BMI)>40 kg m(-)(2)) with T2D. Subsequently, metagenomic data were correlated with clinical indices. Based on gene relative abundance profile, 1061 species, 729 genera, 44 phyla and 5127 KO (KEGG Orthology) were identified. Despite high diversity, bacteria could mostly be assigned to seven bacterial divisions. The overall metagenomic RYGB-induced shift was characterized by a reduction of Firmicutes and Bacteroidetes and an increase of Proteobacteria. Twenty-two microbial species and 11 genera were significantly altered by RYGB. Using principal component analysis, highly correlated species were assembled into two common components. Component 1 consisted of species that were mainly associated with BMI and C-reactive protein. This component was characterized by increased numbers of Proteobacterium Enterobacter cancerogenus and decreased Firmicutes Faecalibacterium prausnitzii and Coprococcus comes. Functional analysis of carbohydrate metabolism by KO revealed significant effects in 13 KOs assigned to phosphotransferase system. Spearmen's Rank correlation indicated an association of 10 species with plasma total- or low-density lipoprotein cholesterol, and 5 species with triglycerides. F. prausnitzii was directly correlated to fasting blood glucose. This is the first clinical demonstration of a profound and specific intra-individual modification of gut microbial composition by full metagenomic sequencing. A clear correlation exists of microbiome composition and gene function with an improvement in metabolic and inflammatory parameters. This will allow to develop new diagnostic and therapeutic strategies based on metagenomic sequencing of the human gut microbiome.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Derivação Gástrica , Inflamação/complicações , Metagenoma , Microbiota , Obesidade/cirurgia , Adulto , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/metabolismo , Período Pós-Operatório
6.
Herz ; 37(3): 244-50, 2012 May.
Artigo em Alemão | MEDLINE | ID: mdl-22441425

RESUMO

In most randomized controlled trials on revascularization therapy for patients with ischemic coronary artery disease (CAD), the diabetes prevalence ranges between 15% and 35%. However, the true prevalence of diabetes is probably considerably underestimated in these trials. The European heart survey diabetes and the heart published in 2004 supplied strong evidence that there are many additional cases of undetected prediabetics and diabetics in any cardiology patient cohort. The long-term outcome of newly detected diabetics was found to be comparable to patients with already known diabetes mellitus. With this in mind, the Dresden silent diabetes study investigated the prevalence of undetected diabetes mellitus by oral glucose tolerance testing (OGTT) and comparative HbA1c sampling in 1,015 patients admitted for coronary angiography. Patients with known diabetes were excluded from the study.According to the OGTT only 513 patients (51%) were classified with normal glucose tolerance (NGT), 10 (1%) with isolated impaired fasting glucose (IFG), 349 (34%) with impaired glucose tolerance (IGT) and 143 (14%) were diagnosed with newly detected diabetes mellitus (DM). According to the HbA1c measurements 588 patients (58%) were classified as normal, 385 (38%) as borderline and only 42 (4%) were diagnosed with diabetes (DM). There was a significant correlation between the extent of CAD and glycemic status as defined by the OGTT. The number of patients with IGT and diabetes increased with the extent of CAD (IGT group p<0.001, diabetes group p=0.01). However, no such correlation was observed when glycemic status was defined by HbA1c testing.Based on these results an OGTT should be routinely performed in patients with known or suspected coronary artery disease undergoing coronary angiography for diagnosis of diabetes, as HbA1c measurements alone appear to miss a substantial proportion of patients. These findings are of high clinical relevance with regard to optimal coronary revascularization procedure chosen in catheterization laboratories, preferably drug-eluting stents in cases of diabetes mellitus or newly detected diabetes mellitus and preferably coronary bypass surgery in diabetics with multi-vessel disease and high SYNTAX scores.


Assuntos
Cateterismo Cardíaco/estatística & dados numéricos , Procedimentos Cirúrgicos Cardiovasculares/estatística & dados numéricos , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/cirurgia , Diabetes Mellitus/epidemiologia , Comorbidade , Alemanha/epidemiologia , Humanos , Prevalência , Medição de Risco , Fatores de Risco
7.
Diabetologia ; 54(11): 2923-30, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21773683

RESUMO

AIMS/HYPOTHESIS: The primary aim of this study was to compare the results of HbA(1c) measurements with those of an OGTT for early diagnosis of 'silent diabetes' in patients with coronary artery disease (CAD) undergoing angiography without prediagnosed diabetes. A secondary aim was to investigate the correlation between the extent of CAD and the glycaemic status of the patient. METHODS: Data from 1,015 patients admitted for acute (n = 149) or elective (n = 866) coronary angiography were analysed. Patients with known diabetes were excluded from the study. Using the OGTT results, patients were classified as having normal glucose tolerance (NGT), impaired fasting glucose (IFG), impaired glucose tolerance (IGT) or diabetes. According to the results of the HbA(1c) measurements, patients were classified into three groups: normal (HbA(1c) <5.7% [<39 mmol/mol]), borderline (HbA(1c) 5.7-6.4% [39-47 mmol/mol]) and diabetes (HbA(1c) ≥6.5% [≥48 mmol/mol]). RESULTS: Based on the OGTT, 513 patients (51%) were classified with NGT, 10 (1%) with IFG, 349 (34%) with IGT and 149 (14%) were diagnosed with diabetes. According to HbA(1c) measurements, 588 patients (58%) were classified as normal, 385 (38%) as borderline and 42 (4%) were diagnosed with diabetes. The proportion of patients with IGT and diabetes increased with the extent of CAD (IGT ρ = 0.14, p < 0.001, diabetes ρ = 0.09, p = 0.01). No differences in HbA(1c) were seen among the groups with different extents of CAD (p = 0.652). CONCLUSIONS/INTERPRETATION: An OGTT should be performed routinely for diagnosis of diabetes in patients with CAD undergoing coronary angiography, since HbA(1c) measurement alone appears to miss a substantial proportion of patients with silent diabetes. A limitation of the study is that the OGTT was not performed before the angiography.


Assuntos
Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Diabetes Mellitus/diagnóstico , Angiopatias Diabéticas/diagnóstico por imagem , Teste de Tolerância a Glucose , Hemoglobinas Glicadas/análise , Programas de Rastreamento/métodos , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Doença da Artéria Coronariana/complicações , Estudos Transversais , Diabetes Mellitus/sangue , Diabetes Mellitus/epidemiologia , Feminino , Alemanha/epidemiologia , Intolerância à Glucose/sangue , Intolerância à Glucose/diagnóstico , Intolerância à Glucose/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estado Pré-Diabético/sangue , Estado Pré-Diabético/diagnóstico , Estado Pré-Diabético/epidemiologia , Prevalência , Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença
8.
Exp Clin Endocrinol Diabetes ; 116(3): 162-6, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18213547

RESUMO

OBJECTIVE: It is a common clinical experience that type 2 diabetic patients are susceptible to opportunistic infections. The underlying reasons for this immune deficiency are not yet understood. Dendritic cells (DC) play a key role in initiating innate and adapted immune responses. DESIGN: In order to investigate changes in the DC compartment in the peripheral blood in type 2 diabetes, we analyzed blood from patients under poor and good metabolic control and compared them to healthy controls. PATIENTS: 5 mls of blood were collected from 15 healthy controls, 15 diabetic patients with an HbA1c <7.0 and 15 patients with an HbA1c >9.5%. Age range was 44-80 years. Patients were age-matched with the control group. MEASUREMENT: Blood DC were enumerated by flow cytometry after staining with antibodies against the blood dendritic cells antigens 1-3 (BDCA 1-3). This allows quantification of the DC subtypes: myeloid dendritic cells type 1 (mDC1, mDC2) and plasmacytoid dendritic cells (pDC). RESULTS: The relative and absolute frequency for both mDC1 and pDC was clearly diminished in patients with poor metabolic control as compared to healthy controls. In patients with good metabolic control the reduction of DC was less pronounced but still significant, particularly for mDC1. CONCLUSION: Hyperglycemic metabolism does affect the pool of peripheral DCs and leads to a reduction of both, mDC1 and pDC. Even patients considered to be under good metabolic control appear to have a reduced peripheral pool of DC.


Assuntos
Células Dendríticas/imunologia , Diabetes Mellitus Tipo 2/imunologia , Idoso , Idoso de 80 Anos ou mais , Contagem de Células , Células Dendríticas/patologia , Diabetes Mellitus Tipo 2/patologia , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade
9.
J Clin Invest ; 104(10): 1449-57, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10562307

RESUMO

During immune responses, antigen-presenting cells (APCs) process antigens and present peptide epitopes complexed with human leukocyte antigen (HLA) molecules. CD4 cells recognize these naturally processed and presented epitopes (NPPEs) bound to HLA class II molecules. Epitope identification is important for developing diagnostic and therapeutic tools for immune-mediated diseases and providing insight into their etiology, but current approaches overlook effects of natural processing on epitope selection. We have developed a technique to identify NPPEs using mass spectrometry (MS) after antigen is targeted onto APCs using a lectin-based antigen delivery system (ADS). We applied the technique to identify NPPEs of the intracellular domain of the type 1 diabetes mellitus-associated (type 1 DM-associated) autoantigen insulinoma-associated-2 (IA-2ic), presented by HLA-DR4 (0401). IA-2ic-derived NPPEs eluted from HLA-DR4 constitute 6 sets of peptides nested around distinct core regions. Synthetic peptides based on these regions bind HLA-DR4 and elicit primary T-cell proliferation frequently in HLA-DR4-positive type 1 DM patients, but rarely in non-HLA-DR4 patients, and in none of the HLA-DR4 nondiabetic controls we tested. This flexible, direct approach identifies an HLA allele-specific map of NPPEs for any antigen, presented by any HLA class II molecule. This method should enable a greater understanding of epitope selection and lead to the generation of sensitive and specific reagents for detecting autoreactive T cells.


Assuntos
Células Apresentadoras de Antígenos/imunologia , Artrite Reumatoide/imunologia , Autoantígenos/imunologia , Diabetes Mellitus Tipo 1/imunologia , Epitopos/imunologia , Antígeno HLA-DR4/imunologia , Ilhotas Pancreáticas/imunologia , Proteínas de Membrana/imunologia , Proteínas Tirosina Fosfatases/imunologia , Adolescente , Adulto , Idoso , Sequência de Aminoácidos , Artrite Reumatoide/genética , Autoanticorpos/análise , Linfócitos B , Linhagem Celular , Membrana Celular/imunologia , Criança , Diabetes Mellitus Tipo 1/genética , Epitopos/química , Epitopos/isolamento & purificação , Europa (Continente) , Genótipo , Humanos , Ativação Linfocitária , Proteínas de Membrana/química , Pessoa de Meia-Idade , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Proteínas Tirosina Fosfatases/química , Proteínas Tirosina Fosfatases Classe 8 Semelhantes a Receptores , Linfócitos T/imunologia , Estados Unidos , População Branca
10.
Exp Clin Endocrinol Diabetes ; 115(8): 491-4, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17853331

RESUMO

AIMS: To evaluate the use of a CGMS in the detection of hypoglycaemia in people with type 2 diabetes as an outpatient procedure. METHODS: 31 type 2 diabetic patients underwent glucose monitoring by means of CGMS (Medtronic MiniMed) for up to three days. Patients took part in at least four SMBG (self monitoring blood glucose) tests per day. After three days of monitoring, the CGMS data was downloaded and analysed by a physician to identify the frequency of hypoglycaemias (< or =50 mg/dl) and borderline values (51-70 mg/dl), their duration and distribution. Findings were discussed with the patient and if necessary treatment was adjusted. Eight weeks later, monitoring was repeated to asses the effects of the adjusted treatment. RESULTS: Average duration of sensor wear was 4.19 days. Correlation between the sensor and the SMBG readings was high. A high number of hypoglycaemias and borderline values were detected by the CGMS, most of them unrecognized by the patient. The frequency of hypoglycaemias and borderline values just as the duration could be significantly reduced from first to second monitoring. CONCLUSION: Using the CGMS in type 2 diabetic patients achieved the detection of numerous hypoglycaemias and borderline values both nocturnal and/or unnoticed. The CGMS provides accurate data, which cannot be achieved by conventional SMBG tests. That opens the possibility for treatment adjustment and improvement in metabolic control. For patients it provides a better understanding of the effects of insulin or oral agents, nutrition and exercises to their glucose level.


Assuntos
Automonitorização da Glicemia , Diabetes Mellitus Tipo 2/sangue , Hipoglicemia/epidemiologia , Monitorização Ambulatorial , Idade de Início , Idoso , Glicemia/análise , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Water Sci Technol ; 56(5): 33-41, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17881835

RESUMO

The present paper reports the approaches adopted to involve and inform stakeholders at various levels and to identify barriers and needed actions towards the implementation of sustainable sanitation concepts in Luxembourg. The study was split into two phases, starting with a workshop and interviews of important actors/professionals of the water sector such as public administrations, engineering companies and sanitary firms. The second phase consisted of a survey among end-users, developed in order to analyse enabling and disabling factors with respect to sustainable water use in households, and for which over 200 questionnaires were evaluated. Valuable conclusions for the project orientation were derived from these studies in terms of further needs for awareness raising, information and formation. The water professionals pointed to specific questions with respect to the feasibility of sustainable sanitation, such as hygienic concerns or maintenance issues for decentralised technology. A moderate financial commitment towards environmentally friendly techniques as well as a considerable lack of knowledge concerning innovative sanitation concepts was detected for end-users. Based on these findings, tailor-made communication strategies for key stakeholder groups were elaborated and pilot projects were initiated.


Assuntos
Conservação dos Recursos Naturais , Saneamento , Luxemburgo , Opinião Pública , Saneamento/economia , Saneamento/métodos , Saneamento/normas , Abastecimento de Água/análise , Abastecimento de Água/economia , Abastecimento de Água/normas
12.
J Neurosci ; 21(4): 1189-202, 2001 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11160389

RESUMO

Assembly of fully functional GABA(B) receptors requires heteromerization of the GABA(B(1)) and GABA(B(2)) subunits. It is thought that GABA(B(1)) and GABA(B(2)) undergo coiled-coil dimerization in their cytoplasmic C termini and that assembly is necessary to overcome GABA(B(1)) retention in the endoplasmatic reticulum (ER). We investigated the mechanism underlying GABA(B(1)) trafficking to the cell surface. We identified a signal, RSRR, proximal to the coiled-coil domain of GABA(B(1)) that when deleted or mutagenized allows for surface delivery in the absence of GABA(B(2)). A similar motif, RXR, was recently shown to function as an ER retention/retrieval (ERR/R) signal in K(ATP) channels, demonstrating that G-protein-coupled receptors (GPCRs) and ion channels use common mechanisms to control surface trafficking. A C-terminal fragment of GABA(B(2)) is able to mask the RSRR signal and to direct the GABA(B(1)) monomer to the cell surface, where it is functionally inert. This indicates that in the heteromer, GABA(B(2)) participates in coupling to the G-protein. Mutagenesis of the C-terminal coiled-coil domains in GABA(B(1)) and GABA(B(2)) supports the possibility that their interaction is involved in shielding the ERR/R signal. However, assembly of heteromeric GABA(B) receptors is possible in the absence of the C-terminal domains, indicating that coiled-coil interaction is not necessary for function. Rather than guaranteeing heterodimerization, as previously assumed, the coiled-coil structure appears to be important for export of the receptor complex from the secretory apparatus.


Assuntos
Membrana Celular/metabolismo , Rim/metabolismo , Neurônios/metabolismo , Transporte Proteico/fisiologia , Receptores de GABA-B/metabolismo , Motivos de Aminoácidos/fisiologia , Cálcio/metabolismo , Linhagem Celular , Dimerização , Retículo Endoplasmático/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Humanos , Imuno-Histoquímica , Rim/citologia , Mutagênese Sítio-Dirigida , Neurônios/citologia , Marcadores de Fotoafinidade/metabolismo , Ligação Proteica/fisiologia , Estrutura Terciária de Proteína/fisiologia , Subunidades Proteicas , Receptores de GABA-B/genética , Receptores de Glutamato Metabotrópico/metabolismo , Transdução de Sinais/fisiologia
13.
Diabetes ; 51(8): 2474-80, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12145160

RESUMO

We investigated the expression of Th1- and Th2-associated chemokine receptors on peripheral blood lymphocytes at diagnosis and in the first phase of type 1 diabetes. Peripheral blood mononuclear cells (PBMCs) of 25 patients with newly diagnosed type 1 diabetes, 10 patients with longstanding type 1 diabetes, and 35 healthy control subjects were examined for expression of the chemokine receptors CXCR4 (naive T-cells), CCR5 and CXCR3 (Th1 associated), and CCR3 and CCR4 (Th2 associated) on CD3+ lymphocytes. Furthermore, we analyzed chemokine serum levels (monocyte chemoattractant protein [MCP]-1, macrophage inflammatory protein [MIP]-1alpha, MIP-1beta, and RANTES [regulated on activation, normal T-cell expressed and secreted]) and phytohemagglutinin (PHA)-stimulated cytokine secretion of Th1- (gamma-interferon [IFN-gamma] and tumor necrosis factor-alpha [TNF-alpha]) and Th2 (interleukin [IL]-4 and -10)-associated cytokines by PBMC. The patients with newly diagnosed type 1 diabetes were followed for these parameters at 6-12 months after diagnosis. The PBMCs of patients with newly diagnosed but not with longstanding type 1 diabetes showed reduced expression of the Th1-associated chemokine receptors CCR5 (P < 0.001 vs. control subjects) and CXCR3 (P < 0.002 vs. control subjects). This reduction correlated with reduced IFN-gamma and TNF-alpha production of PBMCs after PHA stimulation and reversed 6-12 months after diagnosis to normal levels. CCR4 cells were reduced in both newly diagnosed and longstanding type 1 diabetic patients, which correlated to reduced PHA-stimulated IL-4 production. MIP-1alpha and MIP-1beta levels were considerably elevated in a subgroup of patients with newly diagnosed diabetes. We assume that Th1-associated peripheral T-cells are reduced in a narrow time window at the time of diagnosis of diabetes, possibly due to extravasation in the inflamed pancreas. Thus, chemokine receptor expression of peripheral blood lymphocytes may be a useful surrogate marker for the immune activity of type 1 diabetes (e.g., in intervention trials).


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Receptores de Citocinas/biossíntese , Células Th1/imunologia , Adolescente , Quimiocina CCL2/farmacologia , Quimiocina CCL5/farmacologia , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/genética , Regulação da Expressão Gênica , Humanos , Interferon gama/farmacologia , Interleucina-10/farmacologia , Interleucina-4/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Receptores CCR5/biossíntese , Receptores CCR5/genética , Receptores CXCR3 , Receptores CXCR4/biossíntese , Receptores CXCR4/genética , Receptores de Quimiocinas/biossíntese , Receptores de Quimiocinas/genética , Receptores de Citocinas/genética , Valores de Referência
14.
Arch Intern Med ; 152(4): 861-3, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1558449

RESUMO

Although coagulopathy is a well-known complication of severe niacin-induced hepatotoxic reaction, it is not found in patients with minimal aminotransferase level elevations. Three patients with significant clotting factor synthesis deficiency and coagulopathy (prothrombin times, greater than 1.5 times control) from sustained-release niacin had only mild aminotransferase level elevations (1.5 to 2.0 times normal). In each case, protein deficiency, coagulopathy, and aminotransferase level elevation resolved promptly after withdrawal of niacin therapy. In one case, this syndrome recurred after rechallenge with sustained-release niacin, whereas the coagulopathy did not recur in a second patient rechallenged with crystalline niacin. Deficiency in protein synthesis, including coagulation factors, and coagulopathy are unrecognized complications of sustained-release niacin therapy. These cases indicate the need to measure prothrombin times routinely in patients who develop even mild aminotransferase level elevation while receiving sustained-release niacin therapy. These data are important in light of the increasing use of sustained-release niacin in the treatment of patients with lipid disorders.


Assuntos
Transtornos da Coagulação Sanguínea/induzido quimicamente , Fatores de Coagulação Sanguínea/efeitos dos fármacos , Niacina/efeitos adversos , Adulto , Fatores de Coagulação Sanguínea/biossíntese , Humanos , Masculino , Pessoa de Meia-Idade
15.
Arch Intern Med ; 152(4): 837-40, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1558443

RESUMO

BACKGROUND: Continuous quality improvement is being advocated as the process that, if adopted, would improve the efficiency, productiveness, and quality of medical institutions, thereby helping to solve the health care crisis our country is facing. To determine if these techniques could be effective in a tertiary-care multispecialty group practice, a model project was undertaken. The model project chosen was to determine if we could improve the turnaround time for "stat" laboratory examinations performed in our large outpatient facility. METHODS: A 10-member team consisting of everyone involved in the process of laboratory testing was empowered to evaluate the present process and make appropriate changes. With traditional techniques of quality improvement, the process was assessed, data were collected and statistically analyzed, changes were introduced, and data were recollected and analyzed. RESULTS: After intervention, the preanalytic delays were reduced by 76% and the postanalytic delays by 88%. Waiting time for patients was reduced by an average of 62%. By instituting the changes suggested, the institution saved $225,000 on a one-time basis and $40,000 to $50,000 on a recurring basis. CONCLUSION: Adoption of quality improvement techniques appears to be a desirable management paradigm that should be explored by all medical institutions interested in maximizing the quality of care offered while at the same time minimizing its cost.


Assuntos
Laboratórios/normas , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Instituições de Assistência Ambulatorial/organização & administração , Eficiência , Prática de Grupo/organização & administração , Laboratórios/organização & administração , Louisiana , Projetos Piloto , Estudos de Tempo e Movimento
16.
Diabetes Care ; 20(4): 524-9, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9096974

RESUMO

OBJECTIVE: Young age at onset is a relevant parameter associated with a rapid progression of IDDM. Our major aim was to define differences between IDDM patients with age at diagnosis > 40 years and adult IDDM with onset at a younger age. RESEARCH DESIGN AND METHODS: The correlation between islet-related antibodies (islet cell antibodies [ICAs] and antibodies [Abs] to GAD and the tyrosine phosphatase IA2), T-cell responses to GAD peptides and HLA class II isotypes was investigated in 23 IDDM patients 12-38 years of age at onset (group 1), 24 patients with IDDM > 40 years of age at onset (group 2), and 12 healthy control subjects. ICAs were measured by indirect immunofluorescence, and GAD-Ab and IA2-Ab were measured by immunoprecipitation tests. T-cell responses against GAD peptides, which had been identified as typical for IDDM, were tested by 5-day proliferation assays. HLA class II alleles were typed by polymerase chain reaction. RESULTS: ICAs and GAD-Abs were more prevalent in IDDM patients than in control subjects (P < 0.001), but only IDDM group 1 had IA2-Abs (P < 0.001 compared with IDDM group 2 and control subjects). Moreover, antibody combinations differed between IDDM patients of groups 1 and 2. T-cell responses to GAD peptides were seen in 67% of IDDM group 1 and in 71% of IDDM group 2 (P < 0.02 compared with control subjects). IDDM patients of group 1 were more frequently DR4+/DQ8+ and less frequently DR2+/DQ0602+ compared with IDDM patients of group 2 (P < 0.05). CONCLUSIONS: Our data provide strong evidence for humoral and cellular autoimmunity in adult IDDM patients with onset both before and after 40 years of age. However, late-onset differs from young-onset IDDM with respect to Ab profiles, especially a lack of IA2-Ab, and HLA class II types. These findings have consequences for the diagnostic strategy for identifying slow-onset IDDM in individuals after 40 years of age.


Assuntos
Autoanticorpos/sangue , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Antígenos HLA-D/genética , Linfócitos T/imunologia , Adolescente , Adulto , Idade de Início , Alelos , Criança , Progressão da Doença , Técnica Indireta de Fluorescência para Anticorpo , Glutamato Descarboxilase/imunologia , Teste de Histocompatibilidade , Humanos , Ilhotas Pancreáticas/imunologia , Reação em Cadeia da Polimerase
17.
J Clin Endocrinol Metab ; 86(12): 5912-9, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11739463

RESUMO

Pregnancy (including puerperium) is a period of hypercoagulability and seems to be an independent major risk factor for venous thromboembolism (VTE). However, the basis of the increased risk of VTE in pregnancy and around delivery is unknown. We hypothesized that changes in PRL, which is a prominently increased hormone during pregnancy and lactation, might be involved in the activation of platelets. To investigate platelet functional abnormalities in pregnancy, we assessed the ADP-stimulated and nonstimulated P-selectin expression of platelets in 42 consecutive pregnant women, 22 normo- and hyperprolactinemic patients with pituitary tumors, and controls. In addition, the aggregation of platelets by human PRL in vitro was studied. We found a significant correlation between PRL values and ADP stimulation of platelets in pregnant women (r = 0.56; P < 0.0001) and patients with pituitary tumors (r = 0.57; P = 0.006). Hyperprolactinemic pregnant women or hyperprolactinemic patients with pituitary tumors revealed significantly higher ADP stimulation of platelets (P < 0.0001) than healthy controls or normoprolactinemic patients with pituitary tumors. These results were reconciled by increased in vitro stimulation and aggregation of platelets using human PRL. Our novel findings demonstrate that hyperprolactinemia causes increased platelet aggregation via ADP stimulation both in vitro and in vivo. Moreover, our data indicate that PRL may be a physiological cofactor of the delicate coagulation balance during pregnancy and puerperium that might explain the increased risk of VTE in pregnant women around delivery. Further studies of the interaction between PRL and platelets will clarify the clinical relevance of hyperprolactinemia as a potential risk factor for VTE.


Assuntos
Agregação Plaquetária/fisiologia , Prolactina/fisiologia , Adenoma/sangue , Adenoma/complicações , Adenoma/tratamento farmacológico , Difosfato de Adenosina/farmacologia , Adulto , Idoso , Fenômenos Fisiológicos Sanguíneos , Plaquetas/efeitos dos fármacos , Plaquetas/fisiologia , Agonistas de Dopamina/uso terapêutico , Feminino , Humanos , Hiperprolactinemia/sangue , Hiperprolactinemia/complicações , Masculino , Pessoa de Meia-Idade , Hipófise/metabolismo , Neoplasias Hipofisárias/sangue , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/tratamento farmacológico , Gravidez , Prolactina/sangue , Prolactina/farmacologia , Prolactinoma/sangue , Prolactinoma/complicações , Prolactinoma/tratamento farmacológico , Valores de Referência , Hormônio Liberador de Tireotropina/farmacologia , Fatores de Tempo
18.
Hypertension ; 21(6 Pt 2): 971-4, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8505109

RESUMO

In the present investigation we researched the effects of low calorie diet without protein restriction on the renal function and glomerular injury of uninephrectomized spontaneously hypertensive rats. We compared the findings with those that occurred in two different groups of uninephrectomized spontaneously hypertensive rats: one treated with oral hydralazine (10 mg/kg per day) and a second fed regular food. The low calorie diet and hydralazine treatment significantly reduced intra-arterial blood pressure in each group (p < 0.05 and p < 0.001, respectively). The control group showed at the end of the experiment a slight but not significantly different increase in the intra-arterial blood pressure. Low calorie diet was more effective in protecting the kidney function. Creatinine clearance after treatment was significantly higher in uninephrectomized spontaneously hypertensive rats on a low calorie diet than in either the hydralazine-treated or control groups (p < 0.01). The 24-hour urinary protein excretion in the low calorie diet group was significantly lower than in the control group (p < 0.05) and lower but not statistically different from the hydralazine-treated group. The mean glomerular injury index of the remaining kidney in the low calorie diet group was lower than in either the hydralazine-treated or control groups (p < 0.05), and the mean mesangial expansion index in the low calorie diet group was significantly lower than in the control group (p < 0.05). The favorable effect of low calorie diet on renal function was independent of protein restriction or sodium and potassium content.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Dieta Redutora , Proteínas Alimentares/farmacologia , Ingestão de Energia , Rim/efeitos dos fármacos , Rim/patologia , Ratos Endogâmicos SHR/anatomia & histologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Hidralazina/farmacologia , Rim/fisiopatologia , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/patologia , Masculino , Miocárdio/patologia , Nefrectomia , Tamanho do Órgão , Proteinúria/urina , Ratos
19.
J Clin Endocrinol Metab ; 84(11): 4220-7, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10566676

RESUMO

Adrenal androgen production was reduced by 80% in patients receiving T lymphocyte-suppressive medications compared to that in age-matched controls. In vitro, however, neither tacrolimus nor cyclosporin A reduced dehydroepiandrosterone (DHEA) release by adrenocortical cells. Therefore, we examined the potential role of lymphocytes in adrenal androgen production, using cocultures of human T lymphocytes and adrenocortical primary or transformed cells. Co-cultures led to a 4-fold elevation of DHEA levels (490.4 +/- 94.8% over basal), which was greater than the increase observed after the addition of maximal concentrations of ACTH (117.4 +/- 14.8%). Separation of cells by semipermeable membranes abolished this effect, and transfer of leukocyte-conditioned medium had little androgen-stimulating effect. These data suggested that the observed stimulation of androgen secretion required cell contact rather than soluble paracrine factor(s). Furthermore, we examined human adrenal glands for the presence of T lymphocytes and contact between these cells and steroid-secreting cells of the zona reticularis. Indeed, T lymphocytes expressing CD4 and CD8 antigens were present within human adrenal zona reticularis by immunohistochemical subtyping. Electron microscopic analyses demonstrated direct cell-cell contact between T lymphocytes and adrenocortical cells in situ. This study provides evidence for a novel mechanism of immune-endocrine interactions of direct T lymphocyte-adrenocortical cell contact-mediated stimulation of adrenal androgen secretion.


Assuntos
Comunicação Celular , Desidroepiandrosterona/biossíntese , Linfócitos T/fisiologia , Zona Reticular/citologia , Hormônio Adrenocorticotrópico/farmacologia , Androgênios/metabolismo , Linfócitos T CD4-Positivos/fisiologia , Linfócitos T CD8-Positivos/fisiologia , Técnicas de Cocultura , Meios de Cultivo Condicionados , Feminino , Humanos , Imuno-Histoquímica , Imunofenotipagem , Terapia de Imunossupressão , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Fito-Hemaglutininas/farmacologia , Zona Reticular/fisiologia
20.
Am J Cardiol ; 82(12): 1543-5, A8, 1998 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-9874065

RESUMO

In coronary patients with "relatively normal" lipid values and hyperhomocystinemia (levels > or =15 micromol/L), significant 12% reductions in homocysteine levels occurred after cardiac rehabilitation and exercise training. This benefit from cardiac rehabilitation and exercise training may lead to 20% to 30% reductions in overall coronary artery disease risk.


Assuntos
Doença das Coronárias/sangue , Exercício Físico , Homocisteína/sangue , Hiper-Homocisteinemia/sangue , Infarto do Miocárdio/reabilitação , Idoso , Doença das Coronárias/reabilitação , Feminino , Ácido Fólico/sangue , Humanos , Lipoproteínas/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA