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1.
Colorectal Dis ; 15(12): 1529-36, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24034257

RESUMO

AIM: The object of this study was to describe the course of Fournier's gangrene and assess quality of life in a group of affected patients. METHOD: We evaluated patients who received inpatient treatment for Fournier's gangrene at five hospitals in northern Germany from 1995 to 2010. Surviving patients were asked to take part in a clinical follow-up and complete the Short-Form 36 (SF-36) quality-of-life questionnaire and a disease-specific questionnaire including a physical examination. RESULTS: Of the 86 patients, 72 (83.7%) were men. The mean age of the patients was 57.9 ± 13.9 (25-89) years. The mean length of hospital stay was 52.0 ± 54.0 (1-329) days. Fourteen (16.3%) patients (eight men) died primarily from Fournier's gangrene. The most common aetiological event was anogenital abscess formation (n = 24; 27.9%). Seventy-one (82.5%) patients had a mixed polymicrobial infection. SF-36 physical role functioning (P = 0.010), physical functioning (P = 0.008), general health (P = 0.010) and physical health summary (P = 0.006) scores were significantly lower than those of the normal population. Deterioration in sexual function was reported by 65% of the patients. CONCLUSION: Patients with Fournier's gangrene experience persistent physical and mental health problems for a long period of time following their primary hospital stay and must receive long-term care from a variety of specialists, otherwise the disease leads to an increase in the duration of morbidity and a decrease in quality of life.


Assuntos
Antibacterianos/uso terapêutico , Coinfecção/terapia , Desbridamento , Fasciite Necrosante/terapia , Gangrena de Fournier/terapia , Doenças dos Genitais Femininos/terapia , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções por Bacteroidaceae/complicações , Infecções por Bacteroidaceae/psicologia , Infecções por Bacteroidaceae/terapia , Coinfecção/complicações , Coinfecção/psicologia , Infecções por Enterobacteriaceae/complicações , Infecções por Enterobacteriaceae/psicologia , Infecções por Enterobacteriaceae/terapia , Fasciite Necrosante/complicações , Fasciite Necrosante/psicologia , Feminino , Seguimentos , Gangrena de Fournier/complicações , Gangrena de Fournier/psicologia , Doenças dos Genitais Femininos/complicações , Doenças dos Genitais Femininos/psicologia , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Infecções por Pseudomonas/complicações , Infecções por Pseudomonas/psicologia , Infecções por Pseudomonas/terapia , Estudos Retrospectivos , Disfunções Sexuais Fisiológicas/etiologia , Disfunções Sexuais Fisiológicas/psicologia , Infecções Estafilocócicas/complicações , Infecções Estafilocócicas/psicologia , Infecções Estafilocócicas/terapia , Infecções Estreptocócicas/complicações , Infecções Estreptocócicas/psicologia , Infecções Estreptocócicas/terapia , Resultado do Tratamento
2.
Am J Transplant ; 13(9): 2384-94, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23915357

RESUMO

With excellent short-term survival in liver transplantation (LT), we now focus on long-term outcome and report the first European single-center 20-year survival data. Three hundred thirty-seven LT were performed in 313 patients (09/88-12/92). Impact on long-term outcome was studied and a comparison to life expectancy of matched normal population was performed. A detailed analysis of 20-years follow-up concerning overweight (HBMI), hypertension (HTN), diabetes (HGL), hyperlipidemia (HLIP) and moderately or severely impaired renal function (MIRF, SIRF) is presented. Patient and graft survival at 1, 10, 20 years were 88.4%, 72.7%, 52.5% and 83.7%, 64.7% and 46.6%, respectively. Excluding 1-year mortality, survival in the elderly LT recipients was similar to normal population. Primary indication (p < 0.001), age (p < 0.001), gender (p = 0.017), impaired renal function at 6 months (p < 0.001) and retransplantation (p = 0.034) had significant impact on patient survival. Recurrent disease (21.3%), infection (20.6%) and de novo malignancy (19.9%) were the most common causes of death. Prevalence of HTN (57.3-85.2%, p < 0.001), MIRF (41.8-55.2%, p = 0.01) and HBMI (33.2-45%, p = 0.014) increased throughout follow-up, while prevalence of HLIP (78.0-47.6%, p < 0.001) declined. LT has conquered many barriers to achieve these outstanding long-term results. However, much work is needed to combat recurrent disease and side effects of immunosuppression (IS).


Assuntos
Transplante de Fígado/mortalidade , Adolescente , Adulto , Idoso , Índice de Massa Corporal , Feminino , Seguimentos , Alemanha/epidemiologia , Sobrevivência de Enxerto , Humanos , Hiperlipidemias/epidemiologia , Hipertensão/epidemiologia , Terapia de Imunossupressão/efeitos adversos , Nefropatias/epidemiologia , Masculino , Pessoa de Meia-Idade , Reoperação/estatística & dados numéricos , Estudos Retrospectivos
3.
Transplant Proc ; 45(6): 2295-301, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23953541

RESUMO

OBJECTIVES: The Model for End-Stage Liver Disease score and King's College Hospital (KCH) criteria are accepted prognostic models acute liver failure (ALF), while the use of (APACHE) scores predict to outcomes of emergency liver transplantation is rare. MATERIALS AND METHODS: The present study included 87 patients with ALF who underwent liver transplantation. We calculated (KCH) criteria, as well as MELD, APACHE II, and APACHE III scores at the listing date for comparison with 3-month outcomes. RESULTS: According to the Youden-Index, the best cut-off value for the APACHE II score was 8.5 with 100% sensitivity, 49% specificity, 24% positive predictive value (PPV), and 100% negative predictive value (NPV). Patients with <8.5 points had a significantly higher survival rate (P < .05). The proposed APACHE III cut-off was 80. The APACHE III score demonstrated the highest specificity and PPV (90% specificity, 50% PPV). The NPV was 92%. With a 90-point threshold the specificity increased to 98% with 75% PPV and 89% NPV. Only 1 of 4 patients with a score >90 survived transplantation (P = .001). MELD score and KCH criteria were not significant (P > .05). According to the Hosmer-Lemeshow test, only the APACHE III score adequately describe the data. CONCLUSIONS: The APACHE III score was superior to KCH criteria, MELD score, and APACHE II score to predict outcomes after transplantation for ALF. It is a valuable parameter for pretransplantation patient selection.


Assuntos
APACHE , Técnicas de Apoio para a Decisão , Falência Hepática Aguda/diagnóstico , Falência Hepática Aguda/cirurgia , Transplante de Fígado , Adolescente , Adulto , Distribuição de Qui-Quadrado , Criança , Feminino , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Seleção de Pacientes , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
4.
Gastroenterol Res Pract ; 2012: 939350, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23258977

RESUMO

Backround. Pancreas resection is the only curative treatment for pancreatic adenocarcinoma. In the event of unexpected incidental liver metastases during operative exploration patients were traditionally referred to palliative treatment arms. With continuous progress in the surgical expertise simultaneous pancreas and liver resections seem technically feasible nowadays. The aim of this study therefore was to analyze the impact of synchronous liver-directed therapy on operative outcome and overall survival in patients with hepatic metastasized pancreatic adenocarcinoma (HMPA). Methods. 22 patients who underwent simultaneous pancreas resection and liver-directed therapy for HMPA between January 1, 2004 and January 1, 2009 were compared to 22 patients who underwent classic pancreas resection for nonmetastasized pancreatic adenocarcinoma (NMPA) in a matched pair study design. Postoperative morbidity, preoperative, and operative data and overall survival were analyzed. Results. Overall survival was significantly decreased in the HMPA group. Postoperative morbidity and mortality and median operation time did not significantly differ between the groups. Conclusion. The results of our study showed that simultaneous pancreas resection and liver-directed therapy may safely be performed and may therefore be applied in individual patients with HMPA. However, a potential benefit of this radical surgical approach with regard to overall survival and/or quality of life remains to be proven.

6.
Transplant Proc ; 43(10): 3789-95, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22172848

RESUMO

OBJECTIVE: Orthotopic liver transplantation (OLT) is the most effective treatment for patients with end-stage liver disease to date. The discrepancy between the numbers of donor livers and recipients has become a significant problem, resulting in a high patient mortality on the waiting list. Due to this, an expansion of the donor pool is necessary, for example, by accepting donor grafts from elderly donors. The aim of this study was to investigate the outcome after OLT depending on donor age. METHODS: We retrospectively evaluated the outcome of 272 full-size cadaveric initial single OLTs within 12 months after OLT. The outcome was analyzed by dividing the collective into four donor age categories: donor age under 50, between 50 and 59, between 60 and 69, and 70 years or above. The outcome after OLT in these patients was retrospectively reviewed by using a prospective database. Patients positive for hepatitis C were excluded from the analysis. RESULTS: No increase of initial nonfunction was observed. Furthermore, no significant differences with regard to surgical complications and serum liver parameter were observed between the groups. Neither patient mortality rates nor rejection rates were different between the groups. However, ischemic-type biliary lesion rates increased significantly with donor age over 70 years (P<.05). CONCLUSIONS: The acceptance of liver grafts from older donors is a possible alternative to narrow the gap between donated and required organs. Safe use under optimal protocols is necessary to avoid a deterioration of post-OLT results.


Assuntos
Seleção do Doador , Doença Hepática Terminal/cirurgia , Transplante de Fígado , Doadores de Tecidos/provisão & distribuição , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Doença Hepática Terminal/mortalidade , Alemanha , Rejeição de Enxerto/etiologia , Humanos , Estimativa de Kaplan-Meier , Transplante de Fígado/efeitos adversos , Transplante de Fígado/mortalidade , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
7.
Clin Exp Immunol ; 166(1): 46-54, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21762123

RESUMO

Dendritic cell (DC) function is believed to be of critical importance for the pathogenesis of inflammatory bowel disease (IBD). To date, most research in animal models and the few human data available is restricted to myeloid DC, while plasmacytoid DC (pDC) capable of controlling both innate and adaptive immune responses have not yet been investigated systematically in human Crohn's disease (CD) or ulcerative colitis (UC). CD11c(-) , CD303(+) /CD304(+) and CD123(+) pDC from peripheral blood (n = 90), mucosal tissue (n = 28) or mesenteric lymph nodes (n = 40) (MLNs) of patients with UC and CD or controls were purified and cultured. Thereafter, pDC were enumerated, phenotyped and cytokine secretion measured by flow cytometry (FACS), immunohistochemistry and/or cytometric bead array, respectively. Interferon (IFN)-α secretion following cytosine phosphatidyl guanine (CpG) A oligodeoxynucleotide (ODN) 2216 (5'-GGGGGACGATCGTCGGGGGG-3') stimulation was assessed by enzyme-linked immunosorbent assay (ELISA). We found a significantly higher frequency of pDC in the inflamed colonic mucosa and MLN of IBD patients. Moreover, the fraction of CD40 and CD86 expressing cultured peripheral blood pDC was significantly higher in flaring UC and CD patients and their secretion of tumour necrosis factor (TNF)-α, interleukin (IL)-6 and IL-8 were increased significantly compared with controls. In contrast, the IFN-α secretion of peripheral blood pDC isolated from flaring IBD, particularly in UC patients, was reduced significantly compared with controls. Our data suggest an aberrant distribution and function of pDC in IBD, contrary to their generally implicated role as inducers of tolerance. We speculate that the impaired IFN-α secretion may relate to the hypothesized defect in innate immunity in IBD and could also impact upon the generation of regulatory T cells (T(reg) ).


Assuntos
Colite Ulcerativa , Doença de Crohn , Células Dendríticas , Mucosa Intestinal/imunologia , Linfonodos/imunologia , Adulto , Idoso , Antígenos CD/análise , Antígenos CD/biossíntese , Colite Ulcerativa/imunologia , Colite Ulcerativa/patologia , Doença de Crohn/imunologia , Doença de Crohn/patologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Células Dendríticas/patologia , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Interferon-alfa/análise , Interferon-alfa/biossíntese , Interleucina-6/análise , Interleucina-6/biossíntese , Interleucina-8/análise , Interleucina-8/biossíntese , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Linfonodos/efeitos dos fármacos , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Oligodesoxirribonucleotídeos/farmacologia , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/biossíntese
8.
Cardiovasc Intervent Radiol ; 34(6): 1208-13, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21184225

RESUMO

PURPOSE: To evaluate the safety and efficacy of the Amplatzer vascular plug (AVP) for embolization of the splenic artery in patients with hepatic hypoperfusion after orthotopic liver transplantation (OLT). MATERIALS AND METHODS: Thirteen patients (9 men and 4 women) with a mean age of 56 years (range 22-70) who developed splenic artery syndrome after OLT with decreased liver perfusion and clinically relevant impairment of liver function (increased transaminase or serum bilirubin levels, thrombocytopenia, and/or therapy-refractory ascites) were treated by embolization of the proximal third of the splenic artery using the AVP. The plugs ranged in diameter from 6 to 16 mm, and they were introduced through femoral (n = 9), axillary (n = 3), or brachial (n = 1) access using a 5F or 8F guiding catheter. RESULTS: The plugs were successfully placed, and complete occlusion of the splenic artery was achieved in all patients. Placement of two plugs was necessary for complete occlusion in 3 of the 13 patients. Occlusion took on average 10 min (range 4-35). There was no nontarget embolization or plug migration into more distal segments of the splenic artery. All patients showed improved arterial perfusion, including the liver periphery, on postinterventional angiogram. After embolization, liver function parameters (transaminase and bilirubin levels) improved with normalization of concomitant thrombocytopenia and a decrease in ascites volume. CONCLUSION: Our initial experience in a small patient population with SAS suggests that the AVP enables precise embolization of the proximal splenic artery, thus providing safe and effective treatment for poor liver perfusion after OLT due to SAS.


Assuntos
Embolização Terapêutica/instrumentação , Transplante de Fígado , Complicações Pós-Operatórias/terapia , Dispositivo para Oclusão Septal , Artéria Esplênica , Esplenopatias/terapia , Adulto , Idoso , Angiografia , Meios de Contraste , Feminino , Humanos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico por imagem , Esplenopatias/diagnóstico por imagem , Síndrome , Tomografia Computadorizada por Raios X , Resultado do Tratamento
9.
Histochem Cell Biol ; 131(5): 615-28, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19125273

RESUMO

Extracellular nucleotides might influence aspects of the biology of reproduction in that ATP affects smooth muscle contraction, participates in steroidogenesis and spermatogenesis, and also regulates transepithelial transport, as in oviducts. Activation of cellular nucleotide purinergic receptors is influenced by four plasma membrane-bound members of the ectonucleoside triphosphate diphosphohydrolase (E-NTPDase) family, namely NTPDase1, NTPDase2, NTPDase3, and NTPDase8 that differ in their ecto-enzymatic properties. The purpose of this study was to characterize the expression profile of the membrane-bound NTPDases in the murine female and male reproductive tracts by immunological techniques (immunolabelling, Western blotting) and by enzymatic assays, in situ and on tissue homogenates. Other than the expected expression on vascular endothelial and smooth muscle cells, NTPDase1 was also detected in Sertoli cells and interstitial macrophages in testes, in ovarian granulosa cells, and in apical cells from epididymal epithelium. NTPDase2 was largely expressed by cells in the connective tissue; NTPDase3 in secretory epithelia, and finally, NTPDase8 was not detected in any of the tissues studied here. In addition, NTPDase6 was putatively detected in Golgi-phase acrosome vesicles of round spermatids. This descriptive study suggests close regulation of extracellular nucleotide levels in the genital tract by NTPDases that may impact specific biological functions.


Assuntos
Adenosina Trifosfatases/metabolismo , Antígenos CD/metabolismo , Apirase/metabolismo , Ovário/enzimologia , Pirofosfatases/metabolismo , Testículo/enzimologia , Animais , Membrana Celular/enzimologia , Células Endoteliais/enzimologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos de Músculo Liso/metabolismo , Ratos , Ratos Sprague-Dawley
10.
Exp Clin Endocrinol Diabetes ; 114(5): 257-61, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16804800

RESUMO

For patients with concomitant diabetes mellitus an increased perioperative mortality and morbidity in hepatic resections has repeatedly been described. Other studies, however, demonstrated equal outcome data in diabetic and non-diabetic patients. As patient populations were selected for underlying disease, conflicting results may reflect patient selection criteria rather than impact of diabetes mellitus on outcome measures. Therefore, a multivariate analysis in a largely unselected patient population has been performed to determine the independent prognostic value of diabetes mellitus in liver surgery. From a prospective database 633 adult patients undergoing hepatic resection without preceding major abdominal surgery or chemotherapy have been identified. Besides diabetes mellitus, demographic data, variables expressing the functional reserve of the liver, and parameters of surgical technique were analyzed for their impact on mortality and morbidity. 75 patients were diabetic (11.8 %) and 96 hepatic resections (15.2 %) were performed in cirrhotic patients. In the univariate analysis, concomitant diabetes was associated with an increased mortality compared to all non-diabetic patients (10.7 % vs. 5.3 %, p = 0.047). Diabetic patients, however, were also significantly older and presented a higher prevalence of liver cirrhosis. Multivariate modeling finally identified only age, albumin, cirrhosis, extent of surgery, and era of surgery as independent variables with an impact on perioperative mortality. Overall, complications were detected in diabetic and non-diabetic patients with a comparable frequency (44 % vs. 36 %, p = 0.179). Also, the length of in-hospital stay did not significantly differ between both groups (18.5 +/- 1.7 vs. 17.7 +/- 1.0 days, p = 0.119). Rates of postoperative renal impairment, prolonged ascites or pneumonia, however, were higher in diabetics than in other patients. Following established cardiopulmonary and surgical selection criteria, diabetes mellitus is not an independent risk-factor for perioperative mortality in hepatic resections. Although the overall postoperative morbidity was not different in diabetic and non-diabetic patients, a specific pattern of complications has been identified, mandating particular attention in the postoperative course of diabetic patients.


Assuntos
Diabetes Mellitus/epidemiologia , Hepatopatias/cirurgia , Fígado/cirurgia , Procedimentos Cirúrgicos Operatórios/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco
11.
Transplant Proc ; 37(4): 1695-6, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15919434

RESUMO

The aim of this study was to evaluate the success of steroid (PRED) withdrawal due to replacement by mycophenolate mofetil (MMF) in orthotopic liver transplant (OLT) recipients with autoimmune hepatitis (AIH). Thirty patients with AIH > 12 months after OLT randomized to receive either PRED and tacrolimus (TAC) or MMF and TAC were followed for 24 months. Withdrawal of steroids showed no difference regarding graft and patient survival. Also we demonstrated significantly lower glucose levels with lower HbA1c and a reduced need for insulin as well as a significantly lower serum cholesterol in the MMF group. Patients without steroids showed a lower incidence of osteopenia. Maintenance therapy in OLT patients with AIH may be performed safely using MMF instead of prednisone.


Assuntos
Anti-Inflamatórios/uso terapêutico , Hepatite Autoimune/cirurgia , Transplante de Fígado/fisiologia , Ácido Micofenólico/análogos & derivados , Prednisona/uso terapêutico , Tacrolimo/uso terapêutico , Adulto , Anti-Inflamatórios/efeitos adversos , Densidade Óssea , Esquema de Medicação , Quimioterapia Combinada , Feminino , Seguimentos , Hemoglobinas Glicadas/metabolismo , Humanos , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Transplante de Fígado/imunologia , Masculino , Ácido Micofenólico/uso terapêutico , Prednisona/efeitos adversos , Fatores de Tempo
12.
Dtsch Med Wochenschr ; 130(8): 387-92, 2005 Feb 25.
Artigo em Alemão | MEDLINE | ID: mdl-15717248

RESUMO

BACKGROUND AND OBJECTIVE: Intestinal transplantation (ITx) is the only causal therapy of short bowel syndrome (SBS). Long-term survival after ITx has been improved significantly during the last years. The experience with ITx at the Charite, Campus Virchow Klinikum, are described and discussed. PATIENTS AND METHODS: Twelve isolated ITx and one multivisceral transplantation (including stomach, pancreatodudenal complex, small intestine, liver, ascending colon, right kidney, and adrenal gland) were performed. Mean recipient age was 37.7+/-10.6 yrs (median: 35 yrs; range: 27 - 58 yrs; M:F = 8:5). All patients had irreversible SBS (0 - 30 cm residual bowel length; mean: 11.8+/-11.4 cm; median: 13 cm). RESULTS: 6-months and 1-year patient and graft survival were 85 % (11/13) and 77 % (10/13), respectively. Reasons for graft loss and patient death were necrotizing enterocolitis, severe, muromonab-resistent, acute rejection, and graft ischemia due to complex coagulopathy. All other patients had good long-term outcome. They received enteral nutrition at six hours after operation and were persistently off total parenteral nutrition (TPN) by week two after ITx. CONCLUSION: ITx as established in our centre, with 1-year-patient and graft survival rates of 77 %, reflects current international standard. ITx is complementary to conservative and other operative methods of treating SBS. Referral and indication criteria need wider dissemination to prevent life-threatening complications of TPN.


Assuntos
Intestinos/transplante , Síndrome do Intestino Curto/cirurgia , Adolescente , Glândulas Suprarrenais/transplante , Adulto , Berlim , Criança , Nutrição Enteral , Enterocolite Necrosante/complicações , Feminino , Seguimentos , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Imunossupressores/uso terapêutico , Intestino Delgado/transplante , Transplante de Rim , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Transplante de Pâncreas , Nutrição Parenteral Total/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Síndrome do Intestino Curto/terapia , Estômago/transplante , Taxa de Sobrevida , Fatores de Tempo , Doadores de Tecidos/estatística & dados numéricos
16.
Eur J Neurosci ; 12(12): 4357-66, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11122346

RESUMO

Extracellular nucleotides are ubiquitous extracellular mediators that interact with and activate nucleotide type 2 (P2) receptors. These receptors initiate a wide variety of signalling pathways that appear important for functional associations between neurons and glial cells and for the regulation of blood flow, haemostatic and inflammatory reactions in the brain. Ectonucleotidases are extracellular nucleotide-metabolizing enzymes that modulate P2 receptor-mediated signalling by the regulated hydrolysis of these agonists. A considerable number of ectoenzyme species with partially overlapping substrate and tissue distributions have been described. Major candidates for expression in the brain are members of the ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase or CD39) family. The production of cd39-/- mice and specific reagents have enabled us to analyse the specific cellular distribution of NTPDase1 (CD39), the prototype member of the enzyme family, in the mouse brain. Using monospecific antibodies and enzyme histochemical staining, we have identified NTPDase1 as a major ectonucleotidase associated with both microglia and the endothelial and smooth muscle cells of the vasculature. NTPDase1 is not expressed by neurons and astrocytes. Additional unidentified ectonucleotidase functional activity is observed at lower levels throughout the brain parenchyma. NTPDase1 may regulate P2 receptor-mediated functions of microglia as well as influence nucleotide signalling between neurons or astrocytes that are associated with multiple microglial ramifications. The expression of NTPDase1 by cerebrovascular endothelial and smooth muscle cells also suggests involvement in the regulation of blood flow and thrombogenesis.


Assuntos
Antígenos CD/análise , Encéfalo/irrigação sanguínea , Encéfalo/enzimologia , Circulação Cerebrovascular , Endotélio Vascular/enzimologia , Microglia/enzimologia , Músculo Liso Vascular/enzimologia , Hidrolases Anidrido Ácido/análise , Adenosina Trifosfatases/análise , Animais , Antígenos CD/genética , Apirase/análise , Encéfalo/citologia , Células CHO , Células Cultivadas , Cricetinae , Endotélio Vascular/citologia , Camundongos , Camundongos Knockout , Microglia/citologia , Músculo Liso Vascular/citologia , Ratos , Ratos Wistar , Transfecção
17.
Transplantation ; 70(6): 864-70, 2000 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-11014639

RESUMO

BACKGROUND: Extracellular ATP and ADP may be important mediators of vascular inflammation and thrombosis. Nucleoside triphosphate diphosphohydrolase (NTPDase or CD39) is a vascular ectoenzyme that hydrolyses ATP and ADP; however, this activity is lost during reperfusion injury. We show that the supplementation of NTPDase activity within xenograft vasculature using CD39 recombinant adenoviruses (AdCD39) has protective effects in vivo. METHODS: Recombinant adenoviruses containing human CD39 or beta-galactosidase (Adbeta-gal) encoding genes were constructed. Hartley guinea pig coronary arteries were perfused ex vivo with University of Wisconsin solution containing 10(9) plaque-forming units of the recombinant adenovirus. Infected grafts were then implanted in the abdomen of complement depleted Lewis rats. RESULTS: NTPDase activities decreased in all grafts within the first 24 hr and subsequently recovered only in those hearts infected with AdCD39. Immunohistological examination of AdCD39-infected grafts confirmed successful CD39 gene transfer into the endocardium and macrovasculature. Expression of CD39 modestly prolonged graft survival (90.2+/-5.4 hr, mean+/-SD, n=5) when compared with Adbeta-gal-infected grafts (67.4+/-5.4 hr, P<0.005) and perfusion controls (66.4+/-5.2 hr; P<0.005). CONCLUSIONS: Recombinant adenoviral infection can induce expression of CD39 within cardiac xenografts and provide survival benefits in vivo. Our data show that ex vivo infection by recombinant adenovirus vectors can result in vascular expression of a potential therapeutic agent.


Assuntos
Adenosina Trifosfatases , Adenoviridae/genética , Antígenos CD/genética , Vetores Genéticos/imunologia , Transplante de Coração/imunologia , Transplante Heterólogo/imunologia , Animais , Apirase/metabolismo , Western Blotting , Técnicas de Transferência de Genes , Sobrevivência de Enxerto/genética , Cobaias , Humanos , Cinética , Masculino , Ratos , Transplante Heterólogo/patologia
19.
J Biol Chem ; 275(3): 2057-62, 2000 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-10636909

RESUMO

Ectonucleotidases influence purinergic receptor function by the hydrolysis of extracellular nucleotides. CD39 is an integral membrane protein that is a prototype member of the nucleoside 5'-triphosphate diphosphohydrolase family. The native CD39 protein has two intracytoplasmic and two transmembrane domains. There is a large extracellular domain that undergoes extensive glycosylation and can be post-translationally modified by limited proteolysis. We have identified a potential thioester linkage site for S-acylation within the N-terminal region of CD39 and demonstrate that this region undergoes palmitoylation in a constitutive manner. The covalent lipid modification of this region of the protein appears to be important both in plasma membrane association and in targeting CD39 to caveolae. These specialized plasmalemmal domains are enriched in G protein-coupled receptors and appear to integrate cellular activation events. We suggest that palmitoylation could modulate the function of CD39 in regulating cellular signal transduction pathways.


Assuntos
Adenosina Trifosfatases , Antígenos CD/metabolismo , Apirase/metabolismo , Endotélio Vascular/enzimologia , Ácido Palmítico/metabolismo , Animais , Western Blotting , Células COS , Membrana Celular/metabolismo , Células Cultivadas , Cromatografia em Camada Fina , Citoplasma/metabolismo , Endotélio Vascular/ultraestrutura , Humanos , Microscopia Eletrônica , Mutagênese , Transdução de Sinais , Transfecção
20.
Biochemistry ; 38(41): 13473-9, 1999 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-10521254

RESUMO

Vascular ATP diphosphohydrolase/CD39 is an endothelial cell membrane protein with both ecto-ATPase and ecto-ADPase activities. Suppression of constitutive CD39 expression may result in elevated concentrations of ATP and ADP at the vascular interface that could predispose to thrombosis and inflammation. To study the effects of suppression of CD39 synthesis, stable 25-base antisense chimeric oligonucleotides targeting sequences at the 5' region of CD39 were designed. Transfection of these stable oligomers into cultured human endothelial cells resulted in dramatic decreases in levels of CD39 mRNA transcripts. Following transfection with antisense oligonucleotides, total ADPase activity fell from 26.0 +/- 3.1 in control cultures to 9.5 +/- 3.4 nmol of P(i) min(-1) (mg of protein)(-1) (p < 0.005); suppression of CD39 protein expression was also observed by Western blotting. Decreases in ATP diphosphohydrolase activity were associated with increases in concentrations of extracellular purine nucleotides released following stimulation of endothelial cells. Rates of initial hydrolysis of extracellular ATP released from purinergic agonist-stimulated endothelial cells decreased from 17.9 +/- 5.0 to 4.8 +/- 0.5 pmol min(-1) per 10(6) cells (p < 0.005) in antisense transfected cells. Therefore, CD39 regulates extracellular ATP concentrations and may be an important modulator of purinergic receptor activity in vascular endothelial cells.


Assuntos
Adenosina Trifosfatases , Antígenos CD/biossíntese , Apirase/antagonistas & inibidores , Endotélio Vascular/enzimologia , Difosfato de Adenosina/farmacologia , Trifosfato de Adenosina/metabolismo , Antígenos CD/genética , Apirase/biossíntese , Sequência de Bases , Linhagem Celular , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Ativação Enzimática/efeitos dos fármacos , Humanos , Líquido Intracelular/metabolismo , Dados de Sequência Molecular , Oligonucleotídeos Antissenso/metabolismo , Oligonucleotídeos Antissenso/farmacologia , Inibidores da Síntese de Proteínas/farmacologia , RNA Mensageiro/metabolismo , Transfecção , Veias Umbilicais
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