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1.
Lupus ; 32(3): 319-324, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36708185

RESUMO

BACKGROUND: Headache, often migrainous, is common in patients with antiphospholipid antibodies, whether or not they meet Sydney criteria for a definite diagnosis of Hughes syndrome. Migraine may be a harbinger of stroke in this patient population and even refractory migraine may be highly responsive to antithrombotic therapy in this clinical context. PURPOSE: To summarize what is known to date about managing this important manifestation of the immune-mediated hypercoagulable Hughes syndrome. RESULTS: We provide a suggested management algorithm for refractory headache in this unique patient population. CONCLUSION: Most neurologists don't see or recognize many aPL-positive patients in their practice, so hematologists and rheumatologists who see these patients should recognize that refractory headache may be a manifestation of their immune-mediated hypercoagulable disorder and understand that the potential risks of not addressing this issue may be high.


Assuntos
Síndrome Antifosfolipídica , Lúpus Eritematoso Sistêmico , Transtornos de Enxaqueca , Humanos , Síndrome Antifosfolipídica/diagnóstico , Anticorpos Antifosfolipídeos/uso terapêutico , Cefaleia
2.
Bull Environ Contam Toxicol ; 91(4): 438-43, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23934007

RESUMO

Vitellogenin (Vtg) is the major egg-yolk precursor protein in oviparous organisms normally synthesised only in mature females. In males and juveniles, the vtg gene, although present, is silent, but its hepatic expression may be activated by xenoestrogens. Surprisingly, its induction and potential consequences in non-hepatic tissues remain unexplored. Here we test the hepatic and testicular response of vtg expression in adult male rainbowfish Melanotaenia fluviatilis exposed to either 1, 3, 5 µg/L 17ß-estradiol or 100, 500 µg/L 4-n-nonylphenol for 24-96 h. Significant increase in the expression level of vtg mRNA in the liver and testes of exposed males was observed. The early (24 h), sensitive and reliable detection of the vtg induction using qPCR demonstrates the assay's robustness to monitor xenobiotic exposure particularly in smaller fish like rainbowfish, an emerging indicator species. Whilst, the ectopic induction of vtg mRNA in testes suggests a more complex Vtg pathway.


Assuntos
Disruptores Endócrinos/toxicidade , Estrogênios/toxicidade , Testículo/efeitos dos fármacos , Vitelogeninas/genética , Poluentes Químicos da Água/toxicidade , Animais , Expressão Gênica/efeitos dos fármacos , Masculino , RNA Mensageiro/metabolismo , Smegmamorpha , Testículo/metabolismo , Vitelogeninas/metabolismo
3.
Blood Coagul Fibrinolysis ; 9(2): 107-17, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9622208

RESUMO

Pulmonary hypertension is characterized by increased pressure in the pulmonary circulation and, in some cases, inflammation. Significant vascular remodeling occurs in response to these stresses and histopathology demonstrates in-situ thrombosis in a significant number of cases. Elevated shear stresses and inflammation, based on in-vitro data, would be expected to enhance platelet activation and aggregation/adhesion, increase release of von Willebrand factor, increase tissue factor expression, downregulate surface thrombomodulin with diminished thrombin inactivation and decreased protein C activation, and alter fibrinolytic factors with a net loss of fibrinolysis. Data from animal and human studies of pulmonary hypertension provide evidence for increased platelet activation, decreased platelet survival, increased release of von Willebrand factor antigen without an increase in activity, decreased soluble thrombomodulin and a net loss of fibrinolytic activity with excessive release of plasminogen activator inhibitor-1. These changes may result in in-situ thrombosis, which may occur as an inciting event of pulmonary hypertension, or as a consequence of other initiating factors. Chronic anticoagulation has been used in pulmonary hypertension based on observations of increased survival. However, the direct link between altered coagulation and the development or persistence of pulmonary hypertension awaits confirmation.


Assuntos
Hemostasia/fisiologia , Hipertensão Pulmonar/fisiopatologia , Animais , Anticoagulantes/uso terapêutico , Plaquetas/fisiologia , Modelos Animais de Doenças , Fibrinólise/fisiologia , Humanos , Hipertensão Pulmonar/tratamento farmacológico , Trombomodulina/fisiologia , Fator de von Willebrand/fisiologia
4.
Chest ; 110(3): 710-7, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8797416

RESUMO

STUDY OBJECTIVES: Although in situ thrombosis is a prominent finding in lung vessels from patients with primary and secondary pulmonary hypertension, to our knowledge, plasma coagulation factors that might contribute to a hypercoagulable state have not been fully investigated. We hypothesized that the local coagulation environment in the lung vasculature is important to progression if not initiation of pulmonary hypertension. DESIGN: Quasi-experimental cross-sectional design with concurrent controls. SETTING: Referral clinics and inpatient services of a University Hospital and a Veterans Administration Medical Center. PARTICIPANTS: To investigate the role of plasma coagulation factors in severe pulmonary hypertension, we sampled plasma from patients with primary pulmonary hypertension, patients with pulmonary hypertension secondary to a discernible etiology, and normal adult control subjects. RESULTS: We detected abnormalities of the thrombomodulin/protein C anticoagulant system, evidenced by a decrease in soluble thrombomodulin, in patients with primary pulmonary hypertension. In the patients with primary pulmonary hypertension, we found impaired fibrinolytic activity, with a rise in the fibrinolytic inhibitor plasminogen activator 1 and elevated euglobulin lysis time. Lower fibrinolytic activity correlated with high mean pulmonary artery pressure. In contrast, in patients with secondary pulmonary hypertension, von Willebrand factor antigen and fibrinogen levels were increased, and fibrinolytic activity decreased. CONCLUSIONS: Different patterns of coagulation and fibrinolytic abnormalities are apparent in plasma from patients with primary and secondary pulmonary hypertension. Although we are unable to address causality with this study, we speculate that abnormalities of these coagulation mechanisms may initiate or play a role in perpetuation of pulmonary hypertension.


Assuntos
Fatores de Coagulação Sanguínea/análise , Coagulação Sanguínea , Fibrinólise , Hipertensão Pulmonar/fisiopatologia , Adulto , Pressão Sanguínea , Estudos Transversais , Feminino , Hemodinâmica , Humanos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Artéria Pulmonar/fisiopatologia , Respiração , Fator de von Willebrand/análise
5.
Blood ; 85(8): 2238-44, 1995 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-7718896

RESUMO

The incidence of functional asplenia in sickle-hemoglobin C (SC) disease has not been defined, and the use of prophylactic penicillin to prevent life-threatening septicemia in this disorder is controversial. The percentage of red blood cells with pits (pit count) is a reliable assay of splenic function in other disorders but has not been validated in hemoglobin SC disease. To address these issues, we conducted a prospective, multicenter study of splenic function in persons with hemoglobin SC disease. Baseline clinical data were recorded, and red blood cell pit counts were performed on 201 subjects, aged 6 months to 90 years, with hemoglobin SC; 43 subjects underwent radionuclide liver-spleen scanning. Pit counts greater than 20% were associated with functional asplenia as assessed by liver-spleen scan, whereas pit counts less than 20% were found in subjects with preserved splenic function. Pit counts greater than 20% were present in 0 of 59 subjects (0%) less than 4 years of age, in 19 of 86 subjects (22%) 4 to 12 years of age, and in 25 of 56 subjects (45%) greater than 12 years of age. Other subjects with hemoglobin SC, who had previously undergone surgical splenectomy, had higher pit counts (59.7% +/- 9.5%) than splenectomized subjects without hemoglobinopathy (38.5% +/- 8.8%) or with sickle cell anemia (20.5% +/- 1.9%; P < .001). Two subjects with hemoglobin SC disease (not splenectomized), ages 14 and 15 years, with pit counts of 40.3% and 41.7% died from pneumococcal septicemia. These data indicate that functional asplenia occurs in many patients with hemoglobin SC disease, but its development is usually delayed until after 4 years of age. The pit count is a reliable measure of splenic function in hemoglobin SC disease, but values indicative of functional asplenia (> 20% in our laboratory) are higher than in other disorders. The routine administration of prophylactic penicillin to infants and young children with hemoglobin SC disease may not be necessary.


Assuntos
Altitude , Contagem de Eritrócitos , Eritrócitos Anormais , Doença da Hemoglobina SC/fisiopatologia , Hipóxia/sangue , Sistema Fagocitário Mononuclear/fisiopatologia , Sepse/etiologia , Baço/fisiopatologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Colorado , Suscetibilidade a Doenças , Doença da Hemoglobina SC/complicações , Humanos , Hipóxia/complicações , Lactente , Pessoa de Meia-Idade , Estudos Prospectivos , Cintilografia , Risco , Baço/diagnóstico por imagem , Vacúolos/ultraestrutura
6.
Anal Biochem ; 225(1): 1-9, 1995 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-7778757

RESUMO

We report a new gas chromatography-mass spectrometry (GC-MS) method of measurement of red blood cell folates utilizing a stable isotope-labeled bacterial synthesized folate internal standard. The GC-MS method exploits the fact that the common feature of all folate molecules is a p-aminobenzoic acid moiety sandwiched between a pteridine ring and a polyglutamate chain of varying length. In this method, red blood cell folates together with a folate internal standard are specifically purified using bovine folate binding protein and the folates are subsequently chemically cleaved to p-aminobenzoic acid, pteridines, and glutamic acids. Since all six carbon atoms of the benzene ring in the p-aminobenzoic acid moiety of the folate internal standard are labeled with [13C], it is possible to use selected ion monitoring and stable isotope dilution GC-MS to quantitate folates. The method appears to be sensitive, specific, and accurate. The method has been applied to generate a reference range of red blood cell folates based on assay of 25 normal individuals.


Assuntos
Eritrócitos/química , Ácido Fólico/sangue , Receptores de Superfície Celular , Ácido 4-Aminobenzoico/metabolismo , Animais , Isótopos de Carbono , Proteínas de Transporte/metabolismo , Bovinos , Receptores de Folato com Âncoras de GPI , Ácido Fólico/biossíntese , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Marcação por Isótopo/métodos , Lactobacillus/metabolismo , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Med Hypotheses ; 43(4): 239-44, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7838008

RESUMO

Folate, cobalamin and pyridoxine deficiency are associated with psychiatric or neurological symptomatology. Disturbances in sulfur amino acid metabolism leading to accumulation of homocysteine occurs in all three conditions as the metabolism of homocysteine depends on enzymes requiring these vitamins as cofactors. Oxidation products of homocysteine (homocysteine sulfinic acid and homocysteic acid) and cysteine (cysteine sulfinic acid and cysteic acid) are excitatory sulfur amino acids and may act as excitatory neurotransmitters, whereas taurine and hypotaurine (decarboxylation products of cysteic acid and cysteine sulfinic acid) may act as inhibitory transmitters. Homocysteic acid and cysteine sulfinic acid have been considered as endogenous ligands for the N-methyl-D-aspartate (NMDA) type of glutamate receptors. The profile of these sulfur amino acid neurotransmitters could be altered in a similar fashion in states of decreased availability of folate, cobalamin or pyridoxine. It is proposed that the mechanism of neuropsychiatric manifestations in all three conditions result from a combination of two insults to homocysteine catabolism in the brain.


Assuntos
Aminoácidos Sulfúricos/metabolismo , Encefalopatias/etiologia , Aminoácidos Excitatórios/metabolismo , Deficiência de Ácido Fólico/complicações , Transtornos Mentais/etiologia , Deficiência de Vitamina B 12/complicações , Deficiência de Vitamina B 6/complicações , Encéfalo/metabolismo , Humanos , Receptores de N-Metil-D-Aspartato/metabolismo
8.
Anal Biochem ; 220(2): 249-56, 1994 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-7978266

RESUMO

Oxidized sulfur-containing amino acids are recognized as agonists of excitatory amino acid receptors in the mammalian nervous system. Homologues of glutamic acid (homocysteine sulfinic acid and homocysteic acid) and aspartic acid (cysteine sulfinic acid and cysteic acid) have been shown to be agonistic to N-methyl-D-aspartate receptors in animal brain and have been demonstrated in brain tissue. Considerable evidence exists for the role of homocysteic acid and cysteine sulfinic acid as endogenous ligands for excitatory amino acid receptors. We report, for the first time, the quantitation of these compounds in normal human serum, by a newly developed gas chromatography-mass spectrometry method that employs stable isotope-dilution selected ion monitoring using internal standards prepared in our laboratory. We also report new methods of synthesis of stable isotope-labeled internal standards used in measuring cysteine sulfinic acid, cysteic acid, homocysteine sulfinic acid, and homocysteic acid.


Assuntos
Ácido Cisteico/sangue , Cisteína/análogos & derivados , Homocisteína/análogos & derivados , Ácido Aspártico/sangue , Cisteína/sangue , Deutério , Cromatografia Gasosa-Espectrometria de Massas/métodos , Homocisteína/sangue , Humanos , Marcação por Isótopo/métodos , Neurotransmissores , Valores de Referência
9.
Blood Coagul Fibrinolysis ; 5(4): 455-62, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7841299

RESUMO

Antiphospholipid antibodies (aPL) and free protein S (PSF) deficiency have been associated with clinical thrombosis. Previous reports described a high prevalence of these abnormalities in HIV-infected individuals, but suggested there was little associated clinical thrombosis. A cohort of 74 HIV-infected men were studied for aPL, PSF deficiency and the development of thrombosis. aPL, predominantly anticardiolipin antibodies (aCL), were detected in 86% and PSF deficiency in 33%. While 42% of men with aPL also had low PSF levels, there was no correlation between aCL titres or most measures of aPL and PSF levels. However, a strong correlation was noted between a subset of aPL that reacted to phosphatidylethanolamine by hexagonal array assay and low PSF levels. There was no significant correlation between aPL, PSF deficiency and clinical features (medication use, opportunistic infection, CD4 cell count) of HIV in 60 patients for whom clinical information was available. The overall incidence of thrombosis in this group was 18%, and thrombosis developed in 6.6% of those followed prospectively over a median follow-up of 12 months. Development of thrombosis was not significantly correlated with aPL or PSF deficiency, but the high prevalence of these abnormalities may necessitate larger study groups to determine the risk associated with these coagulation changes. Study of a larger group with careful analysis of subsets of aPL, especially those associated with low PSF levels, and longer clinical follow-up could identify the HIV-infected individuals at risk for thrombosis.


Assuntos
Anticorpos Antifosfolipídeos/sangue , Proteínas Inativadoras do Complemento , Infecções por HIV/complicações , Deficiência de Proteína S/complicações , Trombose/etiologia , Adulto , Anticorpos Anticardiolipina/sangue , Proteínas de Transporte/análise , Estudos de Coortes , Seguimentos , Glicoproteínas/análise , Infecções por HIV/sangue , Humanos , Incidência , Inibidor de Coagulação do Lúpus/análise , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Deficiência de Proteína S/sangue , Deficiência de Proteína S/epidemiologia , Estudos Retrospectivos , Trombose/epidemiologia , beta 2-Glicoproteína I
10.
Am J Med ; 96(2): 155-62, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8109600

RESUMO

The purpose of this report is to characterize the acute multiorgan failure syndrome that complicates some episodes of sickle pain. A retrospective chart review was used to identify episodes of sickle pain complicated by the acute failure of at least two of three organs: lung, liver, or kidney. The defining criteria of organ failure were established, and the clinical characteristics, laboratory values, treatment methods, and outcomes were noted in episodes that met the criteria. Seventeen episodes of acute multiorgan failure were identified in 14 patients, 10 with sickle cell anemia and 4 with hemoglobin SC disease. Most episodes occurred during a pain event that was unusually severe for the patient. The onset of organ failure was associated with fever, rapid fall in hemoglobin level and platelet count, nonfocal encephalopathy, and rhabdomyolysis. Bacterial cultures were negative in all but four episodes. Aggressive transfusion therapy was associated with survival and with rapid recovery of organ function in all but one episode. The syndrome developed in patients who had previously exhibited relatively mild disease with little evidence of chronic organ damage and relatively high hemoglobin values in steady state. Acute multiorgan failure syndrome is a severe, life-threatening complication of pain episodes in patients with otherwise mild sickle cell disease. The syndrome appears to be reversed with prompt, aggressive transfusion therapy. High baseline hemoglobin levels may represent a predisposing factor.


Assuntos
Anemia Falciforme/fisiopatologia , Insuficiência de Múltiplos Órgãos/etiologia , Doença Aguda , Injúria Renal Aguda/etiologia , Adulto , Anemia Falciforme/sangue , Anemia Falciforme/terapia , Transfusão de Sangue , Criança , Feminino , Testes Hematológicos , Doença da Hemoglobina SC/fisiopatologia , Humanos , Falência Hepática Aguda/etiologia , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/sangue , Insuficiência de Múltiplos Órgãos/terapia , Insuficiência Respiratória/etiologia , Estudos Retrospectivos , Rabdomiólise/etiologia , Síndrome
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