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1.
Trop Med Int Health ; 21(11): 1481-1488, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27580403

RESUMO

OBJECTIVE: Tropical highland malaria intensifies and shifts to higher altitudes during exceptionally warm years. Above-normal temperatures associated with El Niño during boreal winter months (December-March) may intensify malaria in East African highlands. We assessed the malaria risk for Oromia, the largest region of Ethiopia with around 30 million inhabitants. METHODS: Simple linear regression and spatial analyses were used to associate sea surface temperatures (SST) in the Pacific and surface temperatures in Ethiopia with annual malaria risk in Oromia, based on confirmed cases of malaria between 1982 and 2005. RESULTS: A strong association (R2 = 0.6, P < 0.001) was identified between malaria and sea surface temperatures in the Pacific, anticipating a 70% increase in malaria risk for the period from August 2016 to July 2017. This forecast was quantitatively supported by elevated land surface temperatures (+1.6 °C) in December 2015. When more station data become available and mean March 2016 temperatures from meteorological stations can be taken into account, a more robust prediction can be issued. CONCLUSION: An epidemic warning is issued for Oromia, Ethiopia, between August 2016 and July 2017 and may include the pre-July short malaria season. Similar relationships reported for Madagascar point to an epidemic risk for all East African highlands with around 150 million people. Preparedness for this high risk period would include pre-emptive intradomestic spraying with insecticides, adequate stocking of antimalarials, and spatial extension of diagnostic capacity and more frequent reporting to enable a rapid public health response when and where required.


Assuntos
Surtos de Doenças , El Niño Oscilação Sul , Malária/epidemiologia , Etiópia/epidemiologia , Previsões , Humanos , Temperatura
2.
Nat Commun ; 13(1): 533, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-35087036

RESUMO

The rapid pace of urbanization makes it imperative that we better understand the influence of climate forcing on urban malaria transmission. Despite extensive study of temperature effects in vector-borne infections in general, consideration of relative humidity remains limited. With process-based dynamical models informed by almost two decades of monthly surveillance data, we address the role of relative humidity in the interannual variability of epidemic malaria in two semi-arid cities of India. We show a strong and significant effect of humidity during the pre-transmission season on malaria burden in coastal Surat and more arid inland Ahmedabad. Simulations of the climate-driven transmission model with the MLE (Maximum Likelihood Estimates) of the parameters retrospectively capture the observed variability of disease incidence, and also prospectively predict that of 'out-of-fit' cases in more recent years, with high accuracy. Our findings indicate that relative humidity is a critical factor in the spread of urban malaria and potentially other vector-borne epidemics, and that climate change and lack of hydrological planning in cities might jeopardize malaria elimination efforts.


Assuntos
Umidade , Malária/epidemiologia , Malária/transmissão , Cidades/epidemiologia , Mudança Climática , Ecologia , Epidemias , Humanos , Incidência , Índia/epidemiologia , Malária Falciparum/transmissão , Estudos Retrospectivos , Estações do Ano , Temperatura , Urbanização
3.
Science ; 289(5485): 1766-9, 2000 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-10976073

RESUMO

Analysis of a monthly 18-year cholera time series from Bangladesh shows that the temporal variability of cholera exhibits an interannual component at the dominant frequency of El Niño-Southern Oscillation (ENSO). Results from nonlinear time series analysis support a role for both ENSO and previous disease levels in the dynamics of cholera. Cholera patterns are linked to the previously described changes in the atmospheric circulation of south Asia and, consistent with these changes, to regional temperature anomalies.


Assuntos
Cólera/epidemiologia , Clima , Modelos Estatísticos , Bangladesh/epidemiologia , Cólera/transmissão , Doenças Endêmicas , Previsões , Humanos , Incidência , Redes Neurais de Computação , Dinâmica não Linear , Estações do Ano , Estatísticas não Paramétricas , Temperatura , Tempo (Meteorologia)
4.
Science ; 258(5084): 999-1001, 1992 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-1439810

RESUMO

Abetalipoproteinemia is a human genetic disease that is characterized by a defect in the assembly or secretion of plasma very low density lipoproteins and chylomicrons. The microsomal triglyceride transfer protein (MTP), which is located in the lumen of microsomes isolated from the liver and intestine, has been proposed to function in lipoprotein assembly. MTP activity and the 88-kilodalton component of MTP were present in intestinal biopsy samples from eight control individuals but were absent in four abetalipoproteinemic subjects. This finding suggests that a defect in MTP is the basis for abetalipoproteinemia and that MTP is indeed required for lipoprotein assembly.


Assuntos
Abetalipoproteinemia/etiologia , Intestinos/química , Quilomícrons/metabolismo , Duodeno/química , Duodeno/metabolismo , Duodeno/ultraestrutura , Humanos , Immunoblotting , Intestinos/ultraestrutura , Jejuno/química , Jejuno/metabolismo , Jejuno/ultraestrutura , Lipoproteínas VLDL/biossíntese , Microssomos/química , Microssomos/metabolismo , Microssomos Hepáticos/química , Triglicerídeos/metabolismo
5.
Proc Biol Sci ; 275(1631): 123-32, 2008 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-17999952

RESUMO

The long-term patterns of malaria in the East African highlands typically involve not only a general upward trend in cases but also a dramatic increase in the size of epidemic outbreaks. The role of climate variability in driving epidemic cycles at interannual time scales remains controversial, in part because it has been seen as conflicting with the alternative explanation of purely endogenous cycles exclusively generated by the nonlinear dynamics of the disease. We analyse a long temporal record of monthly cases from 1970 to 2003 in a highland of western Kenya with both a time-series epidemiological model (time-series susceptible-infected-recovered) and a statistical approach specifically developed for non-stationary patterns. Results show that multiyear cycles of malaria outbreaks appear in the 1980s, concomitant with the timing of a regime shift in the dynamics of cases; the cycles become more pronounced in the 1990s, when the coupling between disease and rainfall is also stronger as the variance of rainfall increased at the frequencies of coupling. Disease dynamics and climate forcing play complementary and interacting roles at different temporal scales. Thus, these mechanisms should not be viewed as alternative and their interaction needs to be integrated in the development of future predictive models.


Assuntos
Surtos de Doenças , Malária/epidemiologia , Modelos Biológicos , Plasmodium/crescimento & desenvolvimento , Animais , Simulação por Computador , Humanos , Quênia/epidemiologia , Chuva , Estudos Retrospectivos , Processos Estocásticos
6.
Clin Genet ; 74(6): 546-52, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18786134

RESUMO

Anderson's disease (AD) or chylomicron retention disease (CMRD) is a rare hereditary lipid malabsorption syndrome linked to SARA2 gene mutations. We report in this study a novel mutation in two sisters for which the Sar1b protein is predicted to be truncated by 32 amino acids at its carboxyl-terminus. Because the SARA2 gene is also expressed in the muscle, heart, liver and placenta, extraintestinal clinical manifestations may exist. For the first time, we describe in this study in the two sisters muscular as well as cardiac abnormalities that could be related to the reported expression of SARA2 in these tissues. We also evaluated six other patients for potential manifestations of the SARA2 mutation. The creatine phosphokinase levels were increased in all patients [1.5-9.4 x normal (N)] and transaminases were moderately elevated in five of the eight patients (1.2-2.6 x N), probably related to muscle disease rather than to liver dysfunction. A decreased ejection fraction occurred in one patient (40%, N: 60%). The muscle, liver and placental tissues that were examined had no specific abnormalities and, in particular, no lipid accumulation. These results suggest that myolysis and other extraintestinal abnormalities can occur in AD/CMRD and that the clinical evaluation of patients should reflect this.


Assuntos
Cardiopatias Congênitas/etiologia , Síndromes de Malabsorção/complicações , Síndromes de Malabsorção/genética , Proteínas Monoméricas de Ligação ao GTP/genética , Músculos/anormalidades , Mutação , Adolescente , Adulto , Feminino , Humanos , Masculino , Músculos/patologia , Adulto Jovem
7.
Ned Tijdschr Geneeskd ; 152(49): 2662-6, 2008 Dec 06.
Artigo em Holandês | MEDLINE | ID: mdl-19137965

RESUMO

The revised Dutch College of General Practitioners' practice guideline 'Viral hepatitis and other liver diseases' offers advice in the diagnosis and management of viral hepatitis A, B and C and other liver diseases. The guideline is important for general practitioners as well as specialists in internal medicine and gastroenterology. The emphasis is on the management of chronic hepatitis B en C, because the prevalence of these diseases has increased in the Netherlands and, in addition, the treatment options for chronic hepatitis have improved. Consequently, timely recognition and adequate referral of patients with chronic hepatitis B or hepatitis C have become more important. However, many patients with a chronic liver disease have no symptoms. Therefore, the general practitioner should be aware that a patient visiting the practice with fatigue and malaise could have a liver disease if he or she belongs to a high-risk group or has had high-risk contacts. If the general practitioner repeatedly finds increased liver transaminase values during routine examination of asymptomatic patients, additional diagnostic tests should be performed. Further tests should focus on viral hepatitis as well as on non-alcoholic fatty liver disease and non-alcoholic steatohepatitis or, depending on the history-taking, liver damage due to excessive alcohol, medication or drug use.


Assuntos
Antivirais/uso terapêutico , Medicina de Família e Comunidade/normas , Hepatite Viral Humana/diagnóstico , Hepatite Viral Humana/epidemiologia , Hepatite Viral Humana/tratamento farmacológico , Hepatite Viral Humana/prevenção & controle , Humanos , Países Baixos , Padrões de Prática Médica , Fatores de Risco , Sociedades Médicas
8.
J Clin Invest ; 78(2): 398-410, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2426307

RESUMO

We describe here seven cases (from five kindreds) of Anderson's disease, which is characterized by diarrhea, steatorrhea, hypobetalipoproteinemia with low levels of cholesterol, triglycerides, and phospholipids, and failure to secrete chylomicrons after a fat meal. Enterocytes isolated from intestinal biopsies of patients after overnight fast showed numerous fat droplets, a histological picture resembling that of abetalipoproteinemia. Immunoenzymatic staining of the enterocytes demonstrated large amounts of material that reacted with a polyclonal antiserum to apolipoprotein B. Further, the immunoreactive material was found to react with several different monoclonal antibodies capable of recognizing both the B100 and B48 forms of apoprotein B, but not with any of several monoclonal antibodies capable of recognizing only B100. This suggests that the material in the enterocytes is the B48 form of apoprotein B or a fragment thereof. Additional findings included decreased low density lipoprotein levels with an abnormal chemical composition, abnormal high density lipoprotein2 (HDL2) and HDL3 particle size distributions, and an abnormal HDL apoprotein composition. Increased amounts of proteins having electrophoretic mobilities similar to apo E and the E-AII complex were present. Finally, some cases exhibited additional protein components of apparent molecular weights between 17,000 and 28,000, which was similar to some cases of abetalipoproteinemia. These findings demonstrate that Anderson's disease is not due to the absence of synthesis of intestinal apo B and suggest that it is more complex than previously thought, affecting all the lipoprotein classes.


Assuntos
Abetalipoproteinemia/metabolismo , Apolipoproteínas B/metabolismo , Mucosa Intestinal/metabolismo , Abetalipoproteinemia/patologia , Adolescente , Apolipoproteínas B/análise , Compostos Azo , Transporte Biológico , Criança , Gorduras na Dieta/administração & dosagem , Feminino , Humanos , Técnicas Imunoenzimáticas , Mucosa Intestinal/análise , Mucosa Intestinal/ultraestrutura , Lipídeos/sangue , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino , Coloração e Rotulagem
9.
Ned Tijdschr Geneeskd ; 161: D1538, 2017.
Artigo em Holandês | MEDLINE | ID: mdl-28513413

RESUMO

- The 'Traumatic wounds and bite wounds' treatment guideline by the NHG (Dutch College of General Practitioners) has recommendations for treating traumatic wounds, bite wounds and wound infection.- It is important to distinguish between traumatic wounds and bite wounds because treatment of lacerations and cuts differs from treatment of bites.- Clean a wound under a lukewarm water tap; avoid using disinfectants.- Preferably close traumatic wounds within 12 hours, provided that the wounds have been carefully cleaned and that there are no referral indications. The strict limit of 6 hours has been abandoned because the age of the wound does not seem to be related to increased infection risk.- Do not close bite wounds unless there is a low estimated risk of infection, it is considered cosmetically important, closure is possible within 8 hours, provided that the wounds have been carefully cleaned, and there are no referral indications.


Assuntos
Mordeduras e Picadas/terapia , Clínicos Gerais/normas , Guias de Prática Clínica como Assunto , Infecção dos Ferimentos/prevenção & controle , Humanos , Água
10.
Ned Tijdschr Geneeskd ; 150(41): 2251-6, 2006 Oct 14.
Artigo em Holandês | MEDLINE | ID: mdl-17076359

RESUMO

The practice guideline 'Diabetes mellitus type 2' (second revision) addresses the diagnosis, treatment and management of adults with diabetes mellitus type 2 in general practice. The aim of management is the prevention and treatment of diabetes-related symptoms and complications such as cardiovascular disease, nephro-, retino- and neuropathy. The general practitioner gives the patient education and lifestyle advice and repeats this regularly. In addition, the general practitioner and the patient strive to achieve good glycaemic control. The agent of first choice in the medicinal treatment of all type 2 diabetic patients is metformin. This is continued even after the addition of a sulphonylurea derivative or insulin. This represents a change compared to the previous version of the practice guideline. The indications for thiazolidinediones are limited. To reduce the cardiovascular risk, it is advised to aim at a systolic blood pressure below 140 mmHg. It is also recommended that each patient be prescribed a statin, unless the patient belongs to a subgroup in which the indication for cholesterol lowering therapy is weak or the patient refuses it. Compared to the former guideline, more emphasis is placed on the prevention of nephropathy. The general practitioner is advised to calculate the creatinine clearance yearly and to test for relevant albuminuria in each patient with a life expectancy of 10 years or more. If microalbuminuria is present, the patient is prescribed an angiotensin converting enzyme (ACE) inhibitor, even if the blood pressure is not elevated. The detection of patients with a high risk of diabetic ulcer is also given more emphasis.


Assuntos
Diabetes Mellitus Tipo 2/prevenção & controle , Diabetes Mellitus Tipo 2/terapia , Medicina de Família e Comunidade/normas , Hipoglicemiantes/uso terapêutico , Padrões de Prática Médica , Diabetes Mellitus Tipo 2/complicações , Humanos , Estilo de Vida , Países Baixos , Prevenção Primária , Sociedades Médicas
11.
Biochim Biophys Acta ; 431(3): 481-92, 1976 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-181061

RESUMO

Stimulation of VLDL production by increasing fatty acid availability is now well established. However, a possible regulatory role of glycerol, another lipid precursor, in VLDL synthesis by the liver has not yet been substaniated. The present experiments investigate this problem using the isolated perfused rat liver. [14C] Glycerol uptake and metabolism were studied at two different glycerol concentrations: 1 mumol/perfusate (control) or 1.6 mmol/perfusate. VLDL production and lipid synthesis were investigated using [14C]leucine and several labelled fatty acids as precursors in control and glycerol-overloaded livers. Neoglycogenesis and lipogenesis from glycerol carbons are negligible in our conditions. The absolute amount of glycerol, but not the precentage, taken up by the liver, increased after raising its concentration in the perfusate. A major part of exogenous (plasmatic) glycerol was esterified with endogenous (non plasmatic) fatty acids. Incorporation of radioactive fatty acids into liver or plasma lipids was lower than in the the control group. Significant differences were observed between saturated and unsaturated fatty acids used as lipid precursors. Production of VLDL as assessed by radioactive leucine and fatty acid incorporation in the VLDL of the perfusate was depressed by glycerol. Glycerol partly inhibits the normal stimulation of VLDL production by plasmatic fatty acid overload.


Assuntos
Glicerol/metabolismo , Lipoproteínas VLDL/metabolismo , Fígado/metabolismo , Animais , Transporte Biológico Ativo , Glicerol/farmacologia , Cinética , Leucina/metabolismo , Fígado/efeitos dos fármacos , Fígado/ultraestrutura , Ácidos Oleicos/metabolismo , Perfusão , Ratos
12.
J Med Genet ; 41(4): 249-55, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15060096

RESUMO

INTRODUCTION: It has been estimated that cytogenetically visible rearrangements are present in approximately 1% of newborns. These chromosomal changes can cause a wide range of deleterious developmental effects, including mental retardation (MR). It is assumed that many other cases exist where the cause is a submicroscopic deletion or duplication. To facilitate the detection of such cases, different techniques have been developed, which have differing efficiency as to the number of loci and patients that can be tested. METHODS: We implemented multiplex amplifiable probe hybridisation (MAPH) to test areas known to be rearranged in MR patients (for example, subtelomeric/pericentromeric regions and those affected in microdeletion syndromes) and to look for new regions that might be related to MR. RESULTS: In this study, over 30 000 screens for duplications and deletions were carried out; 162 different loci tested in each of 188 developmentally delayed patients. The analysis resulted in the detection of 19 rearrangements, of which approximately 65% would not have been detected by conventional cytogenetic analysis. A significant fraction (46%) of the rearrangements found were interstitial, despite the fact that only a limited number of these loci have so far been tested. DISCUSSION: Our results strengthen the arguments for whole genome screening within this population, as it can be assumed that many more interstitial rearrangements would be detected. The strengths of MAPH for this analysis are the simplicity, the high throughput potential, and the high resolution of analysis. This combination should help in the future identification of the specific genes that are responsible for MR.


Assuntos
Análise Citogenética/métodos , Deficiência Intelectual/genética , Hibridização de Ácido Nucleico/métodos , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/patologia , Adolescente , Criança , Pré-Escolar , Aberrações Cromossômicas , Feminino , Genoma Humano , Genótipo , Humanos , Masculino , Reação em Cadeia da Polimerase
13.
Diabetes Care ; 22(6): 904-7, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10372239

RESUMO

OBJECTIVE: To assess the value of fasting blood glucose as a parameter for glycemic control in type 2 diabetic patients not using insulin. RESEARCH DESIGN AND METHODS: In 1,020 type 2 diabetic patients treated with diet or oral hypoglycemic agents (OHAs), measurements of fasting plasma glucose (FPG) and HbA1c were taken. In 617 patients, the measurement could be repeated after 3 months. Cross-sectional correlation coefficients were calculated for the association between HbA1c and FPG. Receiver-operating characteristic (ROC)-curve analyses were applied to examine the performance of FPG as a diagnostic test for HbA1c. Longitudinally, the change in FPG was compared with the change in HbA1c, with both correlation measures and ROC curve analyses. RESULTS: Correlation coefficients between HbA1c and FPG and between FPG change and HbA1c change were 0.77 and 0.65, respectively. ROC curve analysis showed that HbA1c is difficult to predict from FPG values: 66% of the patients with good HbA1c (< 7.0%) were identified as such by FPG values < 7.8 mmol/l. As a test for HbA1c change, FPG change performed moderately: the highest combined values of sensitivity and specificity (87.7 and 57%, respectively) were reached at a cutoff point of zero in the range of FPG change values. CONCLUSIONS: FPG and HbA1c values that do not correspond are not rare in type 2 diabetic patients on diet or OHA treatment. HbA1c is difficult to predict from FPG values, and even more difficult is the prediction of HbA1c changes from FPG changes.


Assuntos
Glicemia/análise , Diabetes Mellitus Tipo 2/sangue , Hemoglobinas Glicadas/análise , Glicemia/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Estudos Transversais , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Dieta para Diabéticos , Jejum , Humanos , Hipoglicemiantes/uso terapêutico , Estudos Longitudinais , Reprodutibilidade dos Testes , Fatores de Tempo
14.
Biochimie ; 60(8): 743-53, 1978.
Artigo em Inglês | MEDLINE | ID: mdl-215235

RESUMO

Production of very low density lipoproteins by the liver depends on the cellular availability of fatty acids. It is stimulated by the uptake of free fatty acids from the plasma and by increased lipogenesis and is inhibited by actinomycin D, suggesting that RNA synthesis is involved in the regulation of apolipoprotein synthesis. This hypothesis has been investigated in rats in vivo and in isolated perfused livers with and without stimulation by fatty acid overload: [14C] orotate incorporation in liver polyribosomal RNA is 60 per cent greater in stimulated livers as compared to controls. This increase is primarily due to a higher incorporation in bound polysomes and in those containing at least six ribosomes and does not result from the inhibition of ribonuclease. RNase digestion of polysomal RNA (4.10(-10) M enzyme, 0 degrees C, 3 h) shows that there is twice as much radioactivity in the hydrolyzed RNA of stimulated livers as compared to controls. After partial purification of poly A-rich RNA by affinity chromatography, the mass yield and radioactivity are increased by 100 per cent in stimulated livers as compared to controls. In conclusion, de novo RNA synthesis seems to be necessary for fatty acid stimulation of VLDL production.


Assuntos
Ácidos Graxos/farmacologia , Lipoproteínas VLDL/metabolismo , Fígado/metabolismo , RNA Ribossômico/biossíntese , Animais , Fracionamento Químico/métodos , Cromatografia de Afinidade/métodos , Técnicas In Vitro , Peso Molecular , Ácido Orótico/metabolismo , Polirribossomos/metabolismo , RNA/metabolismo , RNA Mensageiro/análise , Ratos , Ribonucleases/metabolismo , Estimulação Química
15.
Biochimie ; 68(4): 531-41, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2427125

RESUMO

Human serum low density lipoprotein (LDL) is a large (Mr = 2-3 X 10(6), complex particle composed of lipid, protein and carbohydrate. We obtained about 40 mouse spleen-myeloma hybrid cell lines which produce antibodies against LDL. Three of them, SC2, SC3 and SC10, have been cloned and subcloned and their antibody products characterized. They recognize three non-overlapping epitopes in native LDL. Two of them, SC3 and SC10, also are capable of recognizing very low density lipoprotein, (VLDL), whereas SC2 reacts only weakly with VLDL. All three antigenic determinants remain intact, and accessible to antibodies on the LDL protein apo B, prepared by delipidation in a 'non-denaturing' detergent, sodium deoxycholate. However, apo B prepared by organic solvent, ether-ethanol, or sodium dodecyl sulfate (SDS) delipidation, while reacting strongly with SC10, is only poorly recognized by SC2 or SC3. Proteolysis of LDL with trypsin, chymotrypsin, Staphylococcus aureus protease, papain or thermolysin gives, in each case, several non-identical protein fragments which are separable by SDS-polyacrylamide gel electrophoresis. Upon immunoblotting, some of these fragments are now recognized by either SC3 or SC10 but not SC2, some are recognized by both SC3 and SC10, and others are immunologically unreactive. The protein bands that are separated by SDS gel electrophoresis are composed of several non-identical fragments and contain the antigenic sites to differing degrees. Some of the immunologically reactive fragments do not appear to contain carbohydrate. Reduction and carboxymethylation do not destroy the immunoreactivity of LDL toward any of the antibodies; however, modification of lysine residues by citraconic anhydride markedly diminishes the reactivity of LDL toward SC3. It is likely that the two antibodies SC3 and SC10 are directed against different linear amino acid sequences or very stable domains, whereas the third, SC2, is directed against a more fragile conformational domain of apo B.


Assuntos
Anticorpos Monoclonais/imunologia , Apolipoproteínas B/imunologia , Lipoproteínas LDL/imunologia , Animais , Anticorpos Monoclonais/isolamento & purificação , Especificidade de Anticorpos , Eletroforese em Gel de Poliacrilamida , Epitopos/imunologia , Humanos , Hibridomas/imunologia , Técnicas Imunológicas , Lipoproteínas VLDL/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Peso Molecular , Fragmentos de Peptídeos/imunologia
16.
Shock ; 8(5): 313-20, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9361340

RESUMO

The endogenous metabolite adenosine has been recognized as a protective agent in the setting of ischemia-reperfusion. Because the formation of adenosine during ischemia is closely linked to ATP catabolism, and its actions antagonize the deleterious metabolic and cardiovascular consequences of ischemia, it has been named a "retaliatory" metabolite. During recent years, however, the insight into its diverse scope of anti-inflammatory actions has increased considerably. In this review, the beneficial metabolic and cardiovascular actions of adenosine in ischemia and reperfusion are briefly outlined, followed by an extensive discussion of the established and putative anti-inflammatory actions of adenosine in the inflammatory response to ischemia and reperfusion. It is demonstrated that adenosine interferes with activated neutrophil function, neutrophil-endothelial adhesive interactions, the production and release of various inflammatory mediators, the expression of adhesion molecules, and that it activates cellular antioxidant defense systems, thus providing protective effects at multiple levels in the pathogenesis of ischemia and reperfusion. Finally, several potential pharmacological strategies to enhance the "natural defense mechanism" provided by endogenous adenosine are presented.


Assuntos
Adenosina/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Adenosina/metabolismo , Adenosina/farmacologia , Inibidores de Adenosina Desaminase , Adenosina Quinase/antagonistas & inibidores , Trifosfato de Adenosina/farmacologia , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacologia , Animais , Anti-Inflamatórios não Esteroides/metabolismo , Anti-Inflamatórios não Esteroides/farmacologia , Sistema Cardiovascular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Humanos , Precondicionamento Isquêmico , Nucleosídeos/metabolismo , Receptores Purinérgicos P1/metabolismo , Traumatismo por Reperfusão/metabolismo , Ribonucleosídeos/farmacologia
17.
Chest ; 111(3): 577-83, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9118690

RESUMO

STUDY OBJECTIVE: Cardiopulmonary bypass (CPB) induces a generalized inflammatory response, including activation of leukocytes, contributing to postoperative morbidity. The inflammatory pathways leading to this systemic inflammatory response syndrome are considered identical to those involved in septic shock. Therefore, we studied the release of bactericidal/permeability-increasing protein (BPI), lipopolysaccharide binding protein (LBP), and soluble CD14 (sCD14)-all proteins that modulate the effects of lipopolysaccharide (LPS)-in patients undergoing CPB. In addition, the effect of heparin coating of the extracorporeal bypass circuit on the release of these parameters was assessed. DESIGN: Prospective, randomized clinical pilot study. SETTING: Cardiothoracic Surgery Department in a university hospital. PATIENTS: Fourteen patients undergoing elective coronary artery bypass grafting were included. Seven patients underwent CPB using a standard, noncoated extracorporeal circuit, and seven patients had CPB using a heparin-coated extracorporeal circuit (Duraflo II). INTERVENTIONS: Blood samples were taken after induction of anesthesia, just before aortic crossclamping, and 0, 0.5, 1.5, 3, 6, 12, and 24 h after declamping. MEASUREMENTS AND RESULTS: CPB with a noncoated extracorporeal circuit induced a sharp increase in neutrophil-derived BPI, manifest directly after release of the aortic crossclamp, which was significantly attenuated using a heparin-coated system. Also, CPB induced a gradual increase of the acute-phase reactant LBP, which was identical in the noncoated and heparin-coated groups. Systemic release of sCD14 after crossclamp release was significantly higher in the noncoated group compared with the heparin-coated group, but did not rise above baseline levels. CONCLUSIONS: These data confirm that CPB-induced leukocyte activation is attenuated using a heparin-treated extracorporeal circuit and point to the possible role of LPS toxicity-modulating proteins in the systemic inflammatory response after bypass surgery.


Assuntos
Proteínas Sanguíneas/metabolismo , Ponte Cardiopulmonar , Proteínas de Transporte/sangue , Heparina/farmacologia , Receptores de Lipopolissacarídeos/sangue , Lipopolissacarídeos/metabolismo , Glicoproteínas de Membrana , Proteínas de Membrana , Proteínas de Fase Aguda/metabolismo , Peptídeos Catiônicos Antimicrobianos , Ponte Cardiopulmonar/efeitos adversos , Ponte Cardiopulmonar/instrumentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos
18.
J Biochem ; 126(1): 188-93, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10393338

RESUMO

Secretion of triglycerides by the liver in ruminants as components of very low density lipoproteins particles is low as compared with that in primates or rodents. The rate-limiting steps for the hepatic export of very low density lipoproteins have been studied in liver slices to determine the origin of the low lipotropic capacity of calf liver compared to that of rat liver. The rates of production of apolipoprotein B (apo B) and albumin as well as the rate of secretion of VLDL-apolipoproteins were measured during 12-h incubation of liver slices in organo-culture using [35S]methionine-cysteine labeling. Hepatic apo B production was similar in the two animal species but the VLDL-apolipoprotein secretion rate for calf liver slices amounted to only 20% of that observed for rat liver slices. Although calf and rat liver slices synthesized similar amounts of total protein, the hepatic production of albumin, measured in cells and media, was much higher in calf than rat liver slices (around 2.7-fold), whereas the rate secretion of albumin was similar in the two species. Our results showed that the slow rate of secretion of VLDL by calf liver cells was not consecutive to a low rate of synthesis of apo B but rather to a defect in VLDL assembly and/or secretion.


Assuntos
Apolipoproteínas B/metabolismo , Lipoproteínas VLDL/metabolismo , Fígado/metabolismo , Albuminas/metabolismo , Animais , Bovinos , Meios de Cultura , Cisteína/metabolismo , Dipeptídeos/metabolismo , Técnicas In Vitro , Masculino , Metionina/metabolismo , Ácido Oleico/metabolismo , Ratos , Ratos Sprague-Dawley , Especificidade da Espécie , Radioisótopos de Enxofre
19.
Am J Trop Med Hyg ; 55(2): 131-7, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8780449

RESUMO

Following a striking increase in the severity of autumnal outbreaks of Plasmodium falciparum during the last decade in the Northwest Frontier Province (NWFP) of Pakistan, the role of climatologic variables was investigated. A multivariate analysis showed that during the transmission season of P. falciparum, the amount of rainfall in September and October, the temperature in November and December, and the humidity in December were all correlated (r2 = 0.82) with two measures of P. falciparum, the falciparum rate (percent of slides examined positive for P. falciparum) since 1981 and the annual P. falciparum proportion (percent of all malaria infections diagnosed as P. falciparum) since 1978. Climatologic records since 1876 show an increase in mean November and December temperatures by 2 degrees C and 1.5 degrees C, respectively, and in October rainfall. Mean humidity in December has also been increasing since 1950. These climatologic changes in the area appear to have made conditions for transmission of P. falciparum more favorable, and may account for the increase in incidence observed in the NWFP in recent years.


Assuntos
Clima , Surtos de Doenças , Malária Falciparum/epidemiologia , Animais , Anopheles , Humanos , Umidade , Incidência , Insetos Vetores , Malária Falciparum/prevenção & controle , Malária Vivax/epidemiologia , Controle de Mosquitos/métodos , Análise Multivariada , Paquistão/epidemiologia , Chuva , Análise de Regressão , Estações do Ano , Temperatura
20.
Brain Res ; 779(1-2): 205-13, 1998 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-9473673

RESUMO

This study was aimed to identify the neuronal pathways that mediate the handling stress induced increase in the release of dopamine in the medial prefrontal cortex (mPFC) of the rat brain. For that purpose a microdialysis probe was implanted in the ventral tegmental area (VTA) and a second probe was placed in the ipsilateral mPFC. Receptor specific compounds acting on GABA(A) (20 microM muscimol), GABA(B) (50 microM baclofen), acetylcholine (100 microM atropine, 100 microM mecamylamine), NMDA (30, 100 and 300 microM CPP; 300 microM AP-5, 1 mM (+)-HA-966) and non-NMDA receptors (500 microM CNQX) were infused into the VTA by retrograde dialysis, whereas extracellular dopamine was recorded in the ipsilateral mPFC. Intrategmental infusion of muscimol, baclofen, CPP, AP-5, (+)-HA-966 and CNQX decreased extracellular dopamine in the ipsilateral mPFC; atropine and mecamylamine were without effect on the basal values. During infusion of the various compounds rats were gently handled for 15 min. The infusions of muscimol, atropine, mecamylamine and (+)-HA-966 did not modify the handling stress induced increase in extracellular dopamine in the mPFC. However, during intrategmental infusion of baclofen, CPP, AP-5 and CNQX the handling stress induced increase in extracellular dopamine (expressed as % of controls) in the mPFC was suppressed. These results indicate that a glutamatergic projection to the VTA, acting via both NMDA and non-NMDA-glutamate receptors, play a major role in the handling stress-induced increase in dopamine release in the mPFC. In addition the results suggest a certain role for GABAergic neurones, acting via GABA(B) receptors, in the handling response.


Assuntos
Dopamina/metabolismo , Manobra Psicológica , Neurônios Aferentes/fisiologia , Córtex Pré-Frontal/metabolismo , Estresse Fisiológico/fisiopatologia , Área Tegmentar Ventral/fisiologia , Animais , Baclofeno/farmacologia , Masculino , Mecamilamina/farmacologia , Microdiálise/métodos , Muscimol/farmacologia , Ratos , Ratos Wistar , Receptores Colinérgicos/efeitos dos fármacos , Receptores de GABA/efeitos dos fármacos , Receptores de Glutamato/efeitos dos fármacos
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