Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Blood Coagul Fibrinolysis ; 31(1): 43-47, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31789659

RESUMO

: Acquired hemophilia A (AHA) is a rare bleeding disorder caused by autoantibodies against coagulation factor VIII. We conducted a single institution prospective cohort study to assess treatment strategies and long-term outcomes in AHA patients and provide further evidence for effective treatment and relapse timing. A total of 25 patients diagnosed with AHA between 2001 and 2017 at Penn State Hershey Medical Center were prospectively followed. Information was collected on factor VIII activity and inhibitor titer at diagnosis, treatment regimen(s), complete remission, and relapse time. For immunosuppressive therapy (IST), 19 patients were treated initially with prednisone and cyclophosphamide, four were treated with prednisone, one with prednisone and rituximab, and one with prednisone and second-line rituximab. 13/17 (76%) evaluable patients treated with prednisone and cyclophosphamide achieved complete remission. Four patients received rituximab as second-line therapy (inhibitor titers 34, 122, 416, and 768 BU); three achieved complete remission and one died from sepsis. Both evaluable patients receiving initial prednisone alone achieved complete remission. Five relapses occurred from 17 days to 7 years; all were treated with prednisone and cyclophosphamide and achieved complete remission. IST with prednisone and cyclophosphamide is highly effective in achieving and maintaining complete remission, even for relapsed patients. Despite dual IST with prednisone and cyclophosphamide, some patients, particularly with extremely high inhibitor titers, required addition of second-line rituximab to achieve complete remission. This supports rituximab as effective salvage treatment, including for patients with inhibitor titers at least 100-200 BU. Those who experienced relapse often did so years after complete remission, signifying importance of continued monitoring and vigilance.


Assuntos
Hemofilia A/terapia , Estudos de Coortes , Feminino , Humanos , Masculino , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento
2.
Thromb Res ; 182: 75-78, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31472339

RESUMO

OBJECTIVE: Heterozygous Factor V R506Q [Factor V Leiden (FVL)] and prothrombin G20210A (PGM), the most common inherited thrombotic disorders in the Caucasian population, confer a low-moderate risk for first venous thromboembolic (VTE) event. We investigated the thrombotic complications of rare homozygous and compound heterozygous FVL and PGM. METHODS: A cohort of patients with homozygous and compound heterozygous FVL and PGM were evaluated at a major referral center in Central Pennsylvania, USA between June 2001 and March 2019. Data including incidence of first and recurrent thrombosis, associated risk factors, family history and demographics were collected. RESULTS: Seventy-five patients were eligible for analysis: 47 had homozygous FVL, three had homozygous PGM, 19 had compound heterozygous FVL and PGM, five had compound homozygous FVL and heterozygous PGM, and one had compound heterozygous FVL and homozygous PGM. Fifty-nine patients experienced 111 thromboembolic events. Forty-seven percent of first thrombotic events occurred in patients without clinical or surgical conditions predisposing to thrombosis. The rate of recurrent thromboembolism was 59%. The mean time to recurrence was 8.5 years. Ninety percent of recurrent events occurred during times when patients were not treated with anticoagulation. CONCLUSION: Persons with homozygous and compound heterozygous FVL and PGM are at a significantly increased risk of first unprovoked and recurrent VTE. Patients with first thromboembolic events should be considered for long-term anticoagulation.


Assuntos
Fator V/genética , Protrombina/genética , Trombose/genética , Adulto , Feminino , Predisposição Genética para Doença , Heterozigoto , Homozigoto , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Recidiva , Fatores de Risco , Trombofilia/epidemiologia , Trombofilia/genética , Trombose/epidemiologia , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/genética , Adulto Jovem
3.
Cancer Genet ; 230: 37-46, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30497985

RESUMO

OBJECTIVES: To identify and characterize constitutional chromosomal rearrangements that mimic recurrent genetic abnormalities in acute myeloid leukemia (AML). METHODS: Bone marrow and blood chromosome studies were reviewed to identify constitutional rearrangements that resemble those designated by the 2017 revised World Health Organization (WHO) "AML with recurrent genetic abnormalities". Mate-pair sequencing (MPseq) was performed on cases with constitutional chromosome mimics of recurrent AML abnormalities to further define the rearrangement breakpoints. RESULTS: Three cases with constitutional rearrangements were identified, including t(6;9)(p23;q34), inv(16)(p13.1q22), and t(9;22)(q34.1;q12.2). Two cases were bone marrow specimens being evaluated for hematologic neoplasms, while one case was a blood specimen being evaluated for primary ovarian insufficiency. MPseq provided high-resolution and precise rearrangement breakpoints, and resolved the atypical FISH results generated with each rearrangement. CONCLUSIONS: Our findings illustrate that constitutional rearrangements can mimic recurrent genetic abnormalities observed in AML, and we emphasize the importance of correlating genetic data with clinical and hematopathologic information.


Assuntos
Aberrações Cromossômicas , Rearranjo Gênico , Leucemia Mieloide Aguda/diagnóstico , Adulto , Medula Óssea/patologia , Cromossomos Humanos Par 16/genética , Cromossomos Humanos Par 22/genética , Cromossomos Humanos Par 6/genética , Cromossomos Humanos Par 9/genética , Diagnóstico Diferencial , Feminino , Humanos , Cariotipagem/métodos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade
4.
Blood Coagul Fibrinolysis ; 27(7): 761-769, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27467981

RESUMO

The Hemostasis and Thrombosis Research Society (HTRS) Registry was used to monitor the postapproval use of recombinant factor VIIa. The objective of this manuscript is to provide key insights on the demographics of patients with acquired hemophilia in the HTRS Registry. Acquired hemophilia patient registration in HTRS captured age; sex; comorbidities and predisposing conditions; first bleeding location; laboratory parameters; exposure to blood products, factor, and bypassing agents; and initiation of immune suppression/tolerance therapy. Overall, 166 patients with acquired hemophilia were registered in HTRS (83 women, 73 men, median age 70 years); the majority were non-Hispanic whites (61.4%). The most common comorbidities were autoimmune disease (28.4%) and malignancy (14.5%). The most common first site of bleeding was subcutaneous (27.1%); this was more common in whites (29.1%) than blacks (12.5%) and in non-Hispanics (26.4%) than Hispanics (11.8%). Blood product exposure was reported for 33.1% of patients; the most commonly reported product was packed red blood cells (28%). Of the 57 patients with outcome data available for immune tolerance therapy, 26 patients (46%) reported successful treatment, 13 reported unsuccessful treatment (23%), and 18 (32%) were receiving active treatment at the time of registration. The HTRS Registry final analysis provides the only current comprehensive look at acquired hemophilia in the US population, including details on underlying autoimmune diseases and malignancies. Pertinent to recognition and diagnosis of the disease, subcutaneous bleeding as a presenting bleeding symptom was more common in white and non-Hispanic individuals.


Assuntos
Hemofilia A/diagnóstico , Hemostasia/genética , Trombose/genética , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Demografia , Feminino , Humanos , Masculino , Sistema de Registros , Estudos Retrospectivos , Estados Unidos
5.
Blood Coagul Fibrinolysis ; 27(7): 753-760, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26761583

RESUMO

The Hemostasis and Thrombosis Research Society Registry was used to monitor the postapproval use and safety of recombinant activated factor VII (rFVIIa). The objective of this article is to evaluate the data from the Hemostasis and Thrombosis Research Society Registry related to rFVIIa-treated bleeding episodes in patients with acquired hemophilia. For each rFVIIa-treated bleeding episode, the initial dose, total dose, average infused dose, number of doses, and treatment duration were calculated. Efficacy was assessed on a three-point scale. Out of the 166 registered patients with acquired hemophilia, 110 patients were treated for 237 bleeding episodes (139 rFVIIa treated); the majority (70%) were in patients older than 60 years. The most frequently reported bleeding locations were subcutaneous (40%) and mucosal (32%). Subcutaneous bleeding episodes were more commonly reported in women (55% vs. 40% men) and white patients (44 vs. 27% black). Of the 139 rFVIIa-treated bleeding episodes, rFVIIa was used as first-line treatment in 127 bleeding episodes. The median initial dose was 90 µg/kg; the median total dose per episode was 333.5 µg/kg. Physician-rated efficacy of rFVIIa for each bleeding episode was reported as 'bleeding stopped' in 85% of bleeding episodes, 'bleeding slowed' in 11% of bleeding episodes, 'no improvement' in 4% of bleeding episodes, and was not documented in 1 bleeding episode. One thromboembolic event was reported; transient neurologic symptoms were reported in a 31-year-old postpartum patient after 110 doses of rFVIIa. Adequate hemostasis was provided for most rFVIIa-treated bleeding episodes at doses largely conforming to the package insert. No major safety concerns were reported.


Assuntos
Fator VIIa/uso terapêutico , Hemostasia/genética , Trombose/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hemofilia A , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Adulto Jovem
6.
Case Rep Genet ; 2013: 941684, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23662219

RESUMO

The present study investigated the genetic defects underlying severe Factor V deficiency in a 26-year-old Columbian (South America) female and her immediate family (both parents and newborn child) by next generation sequencing (NGS) of the entire F5 gene locus. Five mutations in the coding sequence of F5, including three missense single-nucleotide variants (R2102H, R513K, D107H) and two synonymous variants (A135A , S184S), were identified and confirmed by the Sanger sequencing in the investigated proband (homozygote for all detected mutations), her parents, and her newborn child (all heterozygotic carriers for identified mutations). Each of the three missense variants was previously associated with separate phenotypes, including Factor V deficiency (R2102H), thrombosis (R513K) and frequent miscarriages (D107H). In addition, at least 75 additional single-nucleotide variants (including six novels) were identified in untranslated region of F5.

7.
A A Case Rep ; 1(6): 86-8, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25612185

RESUMO

Inherited Factor V deficiency is a rare bleeding disorder. We describe the genetic analysis and anesthetic management of a parturient with severe Factor V deficiency who presented in spontaneous labor. Good hemostatic conditions were obtained with prophylactic fresh frozen plasma administration of 10 mL/kg. Detailed genetic analysis by next-generation sequencing identified several relevant mutations in the coding part of the Factor V (F5) gene in our patient, her parents, and the newborn.

8.
Case Rep Hematol ; 2012: 257023, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22937322

RESUMO

A 60-years old patient was admitted to a community hospital with septic arthritis. He was treated with antibiotics and subcutaneous unfractionated heparin (UH) was used for venous thromboprophylaxis. After three days, he developed leg deep venous thrombosis and was treated with IV heparin. One day later, the patient developed pulmonary emboli, which was found using ventilation/perfusion scan. He was transferred to the University Hospital for further management. Upon arrival, antibiotic and intravenous UH were continued. Trans-Esophageal Echocardiogram showed a thrombus in the right atrium, a small portion of which extended to the left atrium through a patent foramen ovale. Another large thrombus was noted in the right ventricle, which extended to the pulmonary artery. Review of the patient's medical records revealed a halving of his platelet count three days following the heparin administration. Therefore, HIT seemed very likely. Intravenous UH was stopped and an emergency thrombectomy was performed. ELISA testing of HIT antibodies came negative. This made HIT diagnosis unlikely and the patient received dalteparin. A week later, as the platelet count declined again, HIT antibodies' testing using ELISA and C-14 serotonin release was repeated, and both assays were positive. Argatroban was restarted and the platelet count normalized.

9.
Pharmacotherapy ; 28(12): 1531-6, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19025434

RESUMO

Direct thrombin inhibitors are commonly used anticoagulants in patients with known or suspected heparin-induced thrombocytopenia (HIT). All three direct thrombin inhibitors available in the United States-argatroban, bivalirudin, and lepirudin-are pregnancy category B drugs based on animal studies, but little data are available on the safety of these agents during human pregnancy. Whereas several case reports support the safe use of lepirudin, only one case report has been published with argatroban and none with bivalirudin. We describe a 26-year-old pregnant woman with portal vein thrombosis and thrombocytopenia treated with argatroban for possible HIT during her last trimester. An argatroban infusion was started at 2 microg/kg/minute during her 33rd week of pregnancy, with the dosage titrated based on the activated partial thromboplastin time; infusion rates ranged from 2-8 microg/kg/minute. Treatment continued until her 39th week of pregnancy, when labor was induced. Argatroban therapy was discontinued 7 hours before epidural anesthesia. The patient successfully delivered a healthy male newborn, devoid of any known adverse effects from argatroban. The infant was found to have a small ventricular septal defect and patent foramen ovale at birth, but it is unlikely that these were caused by argatroban since organogenesis occurs in the first trimester. Even though the cause of this patient's thrombocytopenia was later determined to be idiopathic thrombocytopenic purpura, this is an important case that adds to the literature on use of argatroban during pregnancy.


Assuntos
Ácidos Pipecólicos/uso terapêutico , Terceiro Trimestre da Gravidez , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Trombose Venosa/tratamento farmacológico , Adulto , Anticoagulantes/administração & dosagem , Anticoagulantes/uso terapêutico , Arginina/análogos & derivados , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Número de Gestações , Humanos , Recém-Nascido , Infusões Intravenosas , Ácidos Pipecólicos/administração & dosagem , Gravidez , Resultado da Gravidez , Sulfonamidas , Resultado do Tratamento
10.
Thromb Haemost ; 99(6): 1008-12, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18521501

RESUMO

The carboxyl terminal segment of the fibrinogen gamma chain from gamma408-411 plays a crucial role in platelet aggregation via interactions with the platelet receptor alpha(IIb)beta(3). We describe here the first naturally-occurring fibrinogen point mutation affecting this region and demonstrate its effects on platelet interactions. DNA sequencing was used to sequence the proband DNA, and platelet aggregation and direct binding assays were used to quantitate the biological effects of fibrinogen Hershey IV. The Hershey IV proband was found to be heterozygous for two mutations, gammaV411I and gammaR275C. Little difference in aggregation was seen when fibrinogen Hershey IV was compared to normal fibrinogen. However, less aggregation inhibition was observed using a competing synthetic dodecapeptide containing the V411I mutation as compared to the wild-type dodecapeptide. Purified fibrinogen Hershey IV also bound to purified platelet alpha(IIb)beta(3) with a lower affinity than wild-type fibrinogen. These findings show that the gammaV411I mutation results in a decreased ability to bind platelets. In the heterozygous state, however, the available wild-type fibrinogen appears to be sufficient to support normal platelet aggregation.


Assuntos
Plaquetas/metabolismo , Fibrinogênios Anormais/metabolismo , Agregação Plaquetária/genética , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Mutação Puntual , Sítios de Ligação , Análise Mutacional de DNA , Feminino , Fibrinogênios Anormais/genética , Heterozigoto , Humanos , Pessoa de Meia-Idade , Ligação Proteica
11.
Br J Haematol ; 138(1): 117-24, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17555455

RESUMO

Previous studies have shown that a heterozygous mutation in the fibrinogen Aalpha chain gene, which results in an Aalpha R16C substitution, causes fibrinolytic resistance in the fibrin clot. This mutation prevents thrombin cleavage of fibrinopeptide A from mutant Aalpha R16C chains, but not from wild-type Aalpha chains. However, the mechanism underlying the fibrinolytic resistance is unclear. Therefore, this study investigated the biophysical properties of the mutant fibrin that contribute to fibrinolytic resistance. Fibrin clots made from the mutant fibrinogen incorporated molecules containing fibrinopeptide A into the polymerised clot, which resulted in a 'spiky' clot ultrastructure with barbed fibrin strands. The clots were less stiff than normal fibrin and were cross-linked slower by activated FXIII, but had an increased average fiber diameter, were more dense, had smaller pores and were less permeable. Protein sequencing showed that unclottable fibrinogen remaining in the supernatant consisted entirely of homodimeric Aalpha R16C fibrinogen, whereas both cleaved wild-type alpha chains and uncleaved Aalpha R16C chains were in the fibrin clot. Therefore, fibrinolytic resistance of the mutant clots is probably a result of altered clot ultrastructure caused by the incorporation of fibrin molecules containing fibrinopeptide A, resulting in larger diameter fibers and decreased permeability to fibrinolytic enzymes.


Assuntos
Coagulação Sanguínea/genética , Fibrina/metabolismo , Fibrinopeptídeo A/genética , Mutação , Testes de Coagulação Sanguínea , Western Blotting , Elasticidade , Produtos de Degradação da Fibrina e do Fibrinogênio/fisiologia , Fibrinólise , Fibrinopeptídeo A/análise , Microscopia Eletrônica de Varredura , Permeabilidade , Análise de Sequência de Proteína , Viscosidade
12.
ASAIO J ; 53(2): 229-37, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17413565

RESUMO

Little data exist on anticoagulation of young sheep and goats. We tested the effect of heparin, warfarin, and clopidogrel in two sheep and two goats weighing 17-35 kg. Each animal received heparin boluses of 80, 100, and 200 units/kg; goats also received 300, 350, and 400 units/kg. All animals received continuous heparin 40, 60, and 80 units/kg/hour; oral warfarin 0.3, 0.6, and 0.9 mg/kg/day; and oral clopidogrel 75 and 150 mg/day (2.8-3.4 and 5.6-6.9 mg/kg/day). Results were in the form of complete blood counts, activated clotting times (ACT), partial thromboplastin times, prothrombin times, thromboelastograms, and whole-blood lumiaggregometry. After heparin boluses of 200 units/kg, sheep and goats reached mean peak ACTs over 400 seconds. After continuous infusions of 40, 60 and 80 units/kg/hour, sheep and goats exceeded our therapeutic range for ACTs (195-215 seconds for sheep, 155-175 seconds for goats). For warfarin therapy, both sheep and goats required treatment with >0.6 mg/kg/day to achieve INRs over 2.5. Clopidogrel treatment, after 14-17 days of 75-150 mg/day, inhibited sheep platelets by 25-36% and goat platelets by 35-46%. We conclude that young sheep and goats can be safely and effectively anticoagulated with heparin and warfarin, and can also show a modest antiplatelet response to clopidogrel. Doses for each drug were generally higher than those used for humans, and warfarin therapy in sheep may be unpredictable. These results should be useful for developing anticoagulation protocols to test pediatric mechanical circulatory support devices.


Assuntos
Anticoagulantes/farmacologia , Plaquetas/efeitos dos fármacos , Heparina/farmacologia , Ticlopidina/análogos & derivados , Varfarina/farmacologia , Fatores Etários , Animais , Clopidogrel , Relação Dose-Resposta a Droga , Feminino , Cabras , Masculino , Tempo de Tromboplastina Parcial , Agregação Plaquetária/efeitos dos fármacos , Tempo de Protrombina , Ovinos , Tromboelastografia , Ticlopidina/farmacologia , Tempo de Coagulação do Sangue Total
13.
Br J Haematol ; 134(2): 220-6, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16846481

RESUMO

The fibrinogen Aalpha R16C mutation is a common cause of dysfibrinogenaemia and has been previously associated with both bleeding and thrombosis. However, the mechanism underlying the thrombotic phenotype has not yet been elucidated. This report characterises the defect in fibrinolysis seen as a result of the Aalpha R16C mutation. A young patient with dysfibrinogenaemia (fibrinogen Hershey III) was found to be heterozygous for the Aalpha R16C mutation. Functional assays were performed on the purified fibrinogen to characterise clot formation and lysis with plasmin and trypsin. Consistent with previous results, clot formation was diminished. Unexpectedly, fibrinolysis was also delayed. Plasminogen activation was normal, ruling out decreased plasmin generation as the mechanism behind the fibrinolytic resistance. Western blot analysis showed no difference in the amount of bound alpha2-antiplasmin or albumin. When clot lysis was assayed with trypsin substituted for plasminogen, a significant delay was also observed, indicating that defective binding to plasminogen could not explain the fibrinolytic resistance. These results suggest that the defective fibrinolysis is due to increased proteolytic resistance, most likely reflecting changes in clot structure.


Assuntos
Transtornos de Proteínas de Coagulação/genética , Fibrinogênio/genética , Fibrinogênios Anormais/genética , Fibrinólise/genética , Mutação , Pré-Escolar , Transtornos de Proteínas de Coagulação/sangue , Fibrina/metabolismo , Heterozigoto , Humanos , Masculino
14.
Blood ; 105(6): 2274-80, 2005 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-15542584

RESUMO

Immunoproliferative small intestinal disease (IPSID) was recently added to the growing list of infectious pathogen-associated human lymphomas. Molecular and immunohistochemical studies demonstrated an association with Campylobacter jejuni. IPSID is a variant of the B-cell lymphoma of mucosa-associated lymphoid tissue (MALT), which involves mainly the proximal small intestine resulting in malabsorption, diarrhea, and abdominal pain. Geographically, IPSID is most prevalent in the Middle East and Africa. IPSID lymphomas reveal excessive plasma cell differentiation and produce truncated alpha heavy chain proteins lacking the light chains as well as the first constant domain. The corresponding mRNA lacks the variable heavy chain (V(H)) and the constant heavy chain 1 (C(H)1) sequences and contains deletions as well as insertions of unknown origin. The encoding gene sequence reveals a deletion of V region and parts of C(H)1 domain. Cytogenetic studies demonstrated clonal rearrangements involving predominantly the heavy and light chain genes, including t(9;14) translocation involving the PAX5 gene. Early-stage IPSID responds to antibiotics (30%-70% complete remission). Most untreated IPSID patients progress to lymphoplasmacytic and immunoblastic lymphoma invading the intestinal wall and mesenteric lymph nodes, and may metastasize to a distant organ. IPSID lymphoma shares clinical, morphologic, and molecular features with MALT lymphoma, lymphoplasmacytic lymphoma, and plasma cell neoplasms.


Assuntos
Infecções por Campylobacter , Campylobacter jejuni , Doença Imunoproliferativa do Intestino Delgado , Linfoma de Zona Marginal Tipo Células B , Plasmócitos/imunologia , Adolescente , Adulto , África , Infecções por Campylobacter/complicações , Infecções por Campylobacter/genética , Infecções por Campylobacter/imunologia , Infecções por Campylobacter/patologia , Infecções por Campylobacter/terapia , Criança , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 9/genética , Cromossomos Humanos Par 9/imunologia , Feminino , Humanos , Cadeias Leves de Imunoglobulina/genética , Cadeias Leves de Imunoglobulina/imunologia , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/imunologia , Cadeias alfa de Imunoglobulina/genética , Cadeias alfa de Imunoglobulina/imunologia , Doença Imunoproliferativa do Intestino Delgado/etiologia , Doença Imunoproliferativa do Intestino Delgado/genética , Doença Imunoproliferativa do Intestino Delgado/imunologia , Doença Imunoproliferativa do Intestino Delgado/patologia , Doença Imunoproliferativa do Intestino Delgado/terapia , Intestino Delgado/imunologia , Intestino Delgado/patologia , Linfonodos/imunologia , Linfonodos/patologia , Linfoma de Zona Marginal Tipo Células B/etiologia , Linfoma de Zona Marginal Tipo Células B/imunologia , Linfoma de Zona Marginal Tipo Células B/patologia , Linfoma de Zona Marginal Tipo Células B/terapia , Masculino , Mesentério/imunologia , Mesentério/patologia , Oriente Médio , Fator de Transcrição PAX5/genética , Fator de Transcrição PAX5/imunologia , Plasmócitos/patologia , Deleção de Sequência/genética , Deleção de Sequência/imunologia , Translocação Genética/genética , Translocação Genética/imunologia
15.
Am J Physiol Lung Cell Mol Physiol ; 286(3): L546-53, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14617519

RESUMO

Surfactant protein A (SP-A) plays a role in innate host defense. Human SP-A is encoded by two functional genes (SP-A1 and SP-A2), and several alleles have been characterized for each gene. We assessed the effect of in vitro expressed human SP-A genetic variants, on TNF-alpha and IL-8 production by THP-1 cells in the presence of bleomycin, either before or after ozone-induced oxidation of the variants. The oligomerization of SP-A variants was also examined. We found 1) cytokine levels induced by SP-A2 (1A, 1A(0)) were significantly higher than those by SP-A1 (6A(2), 6A(4)) in the presence of bleomycin. 2) In the presence of bleomycin, ozone-induced oxidation significantly decreased the ability of 1A and 1A/6A(4), but not of 6A(4), to stimulate TNF-alpha production. 3) The synergistic effect of bleomycin/SP-A, either before or after oxidation, can be inhibited to the level of bleomycin alone by surfactant lipids. 4) Differences in oligomerization were also observed between SP-A1 and SP-A2. The results indicate that differences among SP-A variants may partly explain the individual variability of pulmonary complications observed during bleomycin chemotherapy and/or in an environment that may promote protein oxidation.


Assuntos
Interleucina-8/genética , Oxidantes Fotoquímicos/farmacologia , Ozônio/farmacologia , Proteína A Associada a Surfactante Pulmonar/genética , Fator de Necrose Tumoral alfa/genética , Animais , Antimetabólitos Antineoplásicos/farmacologia , Produtos Biológicos/farmacologia , Bleomicina/farmacologia , Linhagem Celular , Eletroforese , Humanos , Técnicas In Vitro , Insetos , Mutagênese , Oxirredução , Proteína A Associada a Surfactante Pulmonar/metabolismo
16.
Thromb Haemost ; 88(1): 26-31, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12152671

RESUMO

GammaA/gamma' fibrinogen is a fibrinogen isoform that constitutes about 15% of total plasma fibrinogen. This isoform contains an additional binding site for zymogen factor XIII and for active thrombin, and forms fibrin clots that are resistant to fibrinolysis in vitro. Little is known about the variability of gammaA/gamma' fibrinogen levels in human populations, whereas total fibrinogen levels are known to increase with age and are higher in women than in men. In this report, evidence is presented that, in contrast to total fibrinogen levels, gammaA/gamma' fibrinogen levels showed no significant association with age or gender in a population of normal blood donors. A study of gammaA/gamma' fibrinogen levels in patients undergoing coronary angiography also showed that gammaA/gamma' fibrinogen levels were higher on average in coronary artery disease patients than in patients without coronary artery disease, and that this association was independent of total fibrinogen levels.


Assuntos
Doença da Artéria Coronariana/sangue , Fibrinogênio/análise , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Processamento Alternativo , Estudos de Casos e Controles , Feminino , Fibrinogênio/genética , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , Análise de Regressão , Fatores Sexuais
17.
Am J Physiol Lung Cell Mol Physiol ; 283(1): L94-L102, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12060565

RESUMO

Surfactant protein A (SP-A) plays a role in host defense and inflammation in the lung. In the present study, we investigated the hypothesis that SP-A is involved in bleomycin-induced pulmonary fibrosis. We studied the effects of human SP-A on bleomycin-induced cytokine production and mRNA expression in THP-1 macrophage-like cells and obtained the following results. 1) Bleomycin-treated THP-1 cells increased tumor necrosis factor (TNF)-alpha, interleukin (IL)-8, and IL-1beta production in dose- and time-dependent patterns, as we have observed with SP-A. TNF-alpha levels were unaffected by treatment with cytosine arabinoside. 2) The combined bleomycin-SP-A effect on cytokine production is additive by RNase protection assay and synergistic by enzyme-linked immunosorbent assay. 3) Although the bleomycin effect on cytokine production was not significantly affected by the presence of surfactant lipid, the additive and synergistic effect of SP-A-bleomycin on cytokine production was significantly reduced. We speculate that the elevated cytokine levels resulting from the bleomycin-SP-A synergism are responsible for bleomycin-induced pulmonary fibrosis and that surfactant lipids can help ameliorate pulmonary complications observed during bleomycin chemotherapy.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Produtos Biológicos , Bleomicina/farmacologia , Citocinas/genética , Macrófagos Alveolares/efeitos dos fármacos , Proteolipídeos/farmacologia , Surfactantes Pulmonares/farmacologia , Linhagem Celular , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Ensaio de Imunoadsorção Enzimática , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/imunologia , Humanos , Interleucina-1/genética , Interleucina-8/genética , Macrófagos Alveolares/citologia , Macrófagos Alveolares/imunologia , Proteína A Associada a Surfactante Pulmonar , Proteínas Associadas a Surfactantes Pulmonares , RNA Mensageiro/análise , Ribonucleases , Fator de Necrose Tumoral alfa/genética
18.
Environ Health Perspect ; 110(1): 79-84, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11781168

RESUMO

Ozone exposure can cause inflammation and impaired lung function. Human surfactant protein A (SP-A) may play a role in inflammation by modulating cytokine production by macrophages. SP-A is encoded by two genes, SP-A1 and SP-A2, and several allelic variants have been characterized for each gene. These allelic variants differ among themselves in amino acids that may exhibit differential sensitivity to ozone-induced oxidation and this may produce functional differences. We studied the effects of SP-A variants before and after ozone exposure on the production of tumor necrosis factor (TNF)-alpha and interleukin (IL)-8. These are important proinflammatory cytokines and are expressed by the macrophage-like THP-1 cells. Eight variants were expressed in vitro, characterized by gel electrophoresis, and studied. These included six single-gene SP-A alleles and two SP-A variants derived from both genes. Variants were exposed to ozone at 1 ppm for 4 hr at 37 degrees C, and we compared their ability to stimulate cytokine (TNF-alpha and IL-8) production by THP-1 cells to air-exposed and unexposed SP-A variants. We found that a) SP-A2 variants (1A, 1A(0), 1A(1) stimulate significantly more TNF-alpha and IL-8 production than SP-A1 variants (6A, 6A(2), 6A(4); b) coexpressed SP-A variants (1A(0)/6A(2), 1A(1)/6A(4) have significantly higher activity than single gene products; c) after ozone exposure, all SP-A variants showed a decreased ability to stimulate TNF-alpha and IL-8 production, and the level of the decrease varied among SP-A variants (26-48%); and d) human SP-A from patients with alveolar proteinosis exhibited a minimal decrease (18% and 12%, respectively) in its ability to stimulate TNF-alpha and IL-8 after in vitro ozone exposure. We conclude that biochemical and functional differences exist among SP-A variants, that ozone exposure modulates the ability of SP-A variants to stimulate cytokines by THP-1 cells, and that SP-As from bronchoalveolar lavage (BAL) fluid of certain alveolar proteinosis patients may be oxidized in vivo.


Assuntos
Regulação da Expressão Gênica , Interleucina-8/biossíntese , Oxidantes Fotoquímicos/efeitos adversos , Ozônio/efeitos adversos , Proteolipídeos/farmacologia , Surfactantes Pulmonares/farmacologia , Fator de Necrose Tumoral alfa/biossíntese , Animais , Células CHO , Cricetinae , Humanos , Inflamação , Macrófagos , Proteína A Associada a Surfactante Pulmonar , Proteínas Associadas a Surfactantes Pulmonares , Transfecção
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...