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1.
Am J Transplant ; 17(4): 1042-1049, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27696662

RESUMO

Delayed graft function is a frequent complication following deceased donor renal transplantation, and is closely related to ischemia-reperfusion injury. Experimental and clinical studies have shown protection by remote ischemic conditioning (RIC). We hypothesized that recipient RIC before kidney graft reperfusion reduces the time to graft recovery. This multicenter, blinded, randomized, controlled clinical trial included 225 adult recipients of renal transplants from deceased donors at four transplantation centers in Denmark, Sweden, and the Netherlands. Participants were randomized 1:1 to RIC or sham-RIC. RIC consisted of 4 × 5-min thigh occlusion by an inflatable tourniquet each followed by 5-min deflation, performed during surgery prior to graft reperfusion. The tourniquet remained deflated for sham-RIC. The primary endpoint was the estimated time to a 50% decrease in baseline plasma creatinine (tCr50) calculated from plasma creatinine measurements 30 days posttransplant or 30 days after the last, posttransplant dialysis. No significant differences were observed between RIC and sham-RIC-treated patients in the primary outcome median tCr50 (122 h [95% confidence interval [CI] 98-151] vs. 112 h [95% CI 91-139], p = 0.58), or the number of patients receiving dialysis in the first posttransplant week (33% vs. 35%, p = 0.71). Recipient RIC does not reduce the time to graft recovery in kidney transplantation from deceased donors. ClinicalTrials.gov: NCT01395719.


Assuntos
Função Retardada do Enxerto/prevenção & controle , Precondicionamento Isquêmico/métodos , Transplante de Rim , Traumatismo por Reperfusão/prevenção & controle , Doadores de Tecidos , Adulto , Idoso , Morte , Feminino , Sobrevivência de Enxerto , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Países Baixos
2.
Clin Exp Immunol ; 188(2): 299-310, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28142201

RESUMO

Ageing is associated with changes in the peripheral T cell immune system, which can be influenced significantly by latent cytomegalovirus (CMV) infection. To what extent changes in circulating T cell populations correlate with T cell composition of the lymph node (LN) is unclear, but is crucial for a comprehensive understanding of the T cell system. T cells from peripheral blood (PB) and LN of end-stage renal disease patients were analysed for frequency of recent thymic emigrants using CD31 expression and T cell receptor excision circle content, relative telomere length and expression of differentiation markers. Compared with PB, LN contained relatively more CD4+ than CD8+ T cells (P < 0·001). The percentage of naive and central memory CD4+ and CD8+ T cells and thymic output parameters showed a strong linear correlation between PB and LN. Highly differentiated CD28null T cells, being CD27- , CD57+ or programmed death 1 (PD-1+ ), were found almost exclusively in the circulation but not in LN. An age-related decline in naive CD4+ and CD8+ T cell frequency was observed (P = 0·035 and P = 0·002, respectively) within LN, concomitant with an increase in central memory CD8+ T cells (P = 0·033). Latent CMV infection increased dramatically the frequency of circulating terminally differentiated T cells, but did not alter T cell composition and ageing parameters of LN significantly. Overall T cell composition and measures of thymic function in PB and LN are correlated strongly. However, highly differentiated CD28null T cells, which may comprise a large part of circulating T cells in CMV-seropositive individuals, are found almost exclusively within the circulation.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Falência Renal Crônica/imunologia , Linfonodos/imunologia , Idoso , Envelhecimento/imunologia , Antígenos de Diferenciação de Linfócitos T/análise , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular , Infecções por Citomegalovirus/imunologia , Feminino , Humanos , Memória Imunológica , Linfonodos/citologia , Ativação Linfocitária , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Latência Viral
3.
J Transl Med ; 14: 20, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26791565

RESUMO

Kidney transplantation is the treatment of choice in patients with end stage renal disease. During kidney transplantation ischemia reperfusion injury (IRI) occurs, which is a risk factor for acute kidney injury, delayed graft function and acute and chronic rejection. Kidneys from living donors show a superior short- and long-term graft survival compared with deceased donors. However, the shortage of donor kidneys has resulted in expansion of the donor pool by using not only living- and brain death donors but also kidneys from donation after circulatory death and from extended criteria donors. These grafts are associated with an increased sensitivity to IRI and decreased graft outcome due to prolonged ischemia and donor comorbidity. Therefore, preventing or ameliorating IRI may improve graft survival. Animal experiments focus on understanding the mechanism behind IRI and try to find methods to minimize IRI either before, during or after ischemia. This review evaluates the different experimental strategies that have been investigated to prevent or ameliorate renal IRI. In addition, we review the current state of translation to the clinical setting. Experimental research has contributed to the development of strategies to prevent or ameliorate IRI, but promising results in animal studies have not yet been successfully translated to clinical use.


Assuntos
Isquemia/terapia , Transplante de Rim , Rim/irrigação sanguínea , Traumatismo por Reperfusão/terapia , Pesquisa Translacional Biomédica , Animais , Humanos , Rim/patologia , Resultado do Tratamento
5.
Br J Surg ; 103(2): e62-72, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26662845

RESUMO

BACKGROUND: Transplant surgery is facing a shortage of deceased donor organs. In response, the criteria for organ donation have been extended, and an increasing number of organs from older donors are being used. For recipients, the benefits of transplantation are great, and the growing ageing population has led to increasing numbers of elderly patients being accepted for transplantation. METHODS: The literature was reviewed to investigate the impact of age of donors and recipients in abdominal organ transplantation, and to highlight aspects of the fine balance in donor and recipient selection and screening, as well as allocation policies fair to young and old alike. RESULTS: Overall, kidney and liver transplantation from older deceased donors have good outcomes, but are not as good as those from younger donors. Careful donor selection based on risk indices, and potentially biomarkers, special allocation schemes to match elderly donors with elderly recipients, and vigorous recipient selection, allows good outcomes with increasing age of both donors and recipients. The results of live kidney donation have been excellent for donor and recipient, and there is a trend towards inclusion of older donors. Future strategies, including personalized immunosuppression for older recipients as well as machine preservation and reconditioning of donor organs, are promising ways to improve the outcome of transplantation between older donors and older recipients. CONCLUSION: Kidney and liver transplantation in the elderly is a clinical reality. Outcomes are good, but can be optimized by using strategies that modify donor risk factors and recipient co-morbidities, and personalized approaches to organ allocation and immunosuppression.


Assuntos
Transplante de Rim/métodos , Transplante de Fígado/métodos , Idoso , Previsões , Humanos , Terapia de Imunossupressão/métodos , Transplante de Rim/ética , Transplante de Fígado/ética , Doadores Vivos/ética , Doadores Vivos/estatística & dados numéricos , Doadores Vivos/provisão & distribuição , Prognóstico , Doadores de Tecidos/estatística & dados numéricos , Doadores de Tecidos/provisão & distribuição , Obtenção de Tecidos e Órgãos/estatística & dados numéricos
6.
Am J Transplant ; 15(6): 1701-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25833120

RESUMO

In 2006, a survey from the American Society of Transplant Surgeons disclosed significant and sometimes fatal hemorrhagic events in live donor nephrectomies (LDN) related to failure of clips, leading to the contraindication of the Weck® Hem-o-lok® clip for control of the renal artery during LDN. A survey regarding vascular control techniques, their perceived safety ratings and their failures was sent to 645 European Society for Organ Transplantation members who profiled their profession as "surgeon" and selected "kidney" as organ type. Two hundred forty-three (41%) members responded, of whom 171 (63.3%) independently perform LDN. Their responses were analyzed. For arterial and venous vascular control, the GIA™ and TA™stapler are used most frequently, and were rated the safest. Of the 121 reported hemorrhagic events, slippage and dislodgement of clips occurred at least 58 times, while stapler malfunction occurred at least 40 times. One donor death from hemorrhage related to clip dysfunction was reported. Hemorrhagic complications of LDN with fatal and non-fatal outcomes still occur. Strikingly, many surgeons do not use the vascular closing technique that they consider most safe. Failure of non-transfixion techniques is associated with greater risks for the donor. Control of major vessels in LDN must employ transfixion techniques for optimal donor safety.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Transplante de Rim , Rim/cirurgia , Doadores Vivos , Nefrectomia/métodos , Cirurgiões/estatística & dados numéricos , Inquéritos e Questionários , Adulto , Feminino , Humanos , Rim/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Sistemas On-Line , Segurança do Paciente , Fatores de Risco , Instrumentos Cirúrgicos/efeitos adversos , Grampeadores Cirúrgicos/efeitos adversos , Suturas/efeitos adversos
7.
Am J Transplant ; 15(11): 2947-54, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26153103

RESUMO

The aim of this study is to review the surgical outcome of kidney retransplantation in the ipsilateral iliac fossa in comparison to first kidney transplants. The database was screened for retransplantations between 1995 and 2013. Each study patient was matched with 3 patients with a first kidney transplantation. Just for graft and patient survival analyses, we added an extra control group including all patients receiving a second transplantation in the contralateral iliac fossa. We identified 99 patients who received a retransplantation in the ipsilateral iliac fossa. There was significantly more blood loss and longer operative time in the retransplantation group. The rate of vascular complications and graft nephrectomies within 1 year was significantly higher in the study group. The graft survival rates at 1 year and 3, 5, and 10 years were 76%, 67%, 61%, and 47% in the study group versus 94%, 88%, 77%, and 67% (p < 0.001) in the first control group versus 91%, 86%, 78%, and 57% (p = 0.008) in the second control group. Patient survival did not differ significantly between the groups. Kidney retransplantation in ipsilateral iliac fossa is surgically challenging and associated with more vascular complications and graft loss within the first year after transplantation. Whenever feasible, the second renal transplant (first retransplant) should be performed contralateral to the prior failed one.


Assuntos
Transplante de Rim/efeitos adversos , Nefrectomia/métodos , Reimplante/métodos , Centros Médicos Acadêmicos , Adulto , Estudos de Casos e Controles , Feminino , Seguimentos , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Estimativa de Kaplan-Meier , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade , Países Baixos , Duração da Cirurgia , Modelos de Riscos Proporcionais , Reoperação/métodos , Reimplante/efeitos adversos , Estudos Retrospectivos , Medição de Risco , Estatísticas não Paramétricas , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
8.
Rev Epidemiol Sante Publique ; 61(4): 375-87, 2013 Aug.
Artigo em Francês | MEDLINE | ID: mdl-23835150

RESUMO

BACKGROUND: Epidemiological studies have investigated the health impacts of local sources of environmental pollution using as an outcome variable self-reported health, reflecting the overall perception interviewed people have of their own health. This work aims at analyzing the advantages and the results of this approach. A first step focused on describing the indicators. METHODS: The literature on indicators of self-reported health was reviewed, leading to a discussion on data collection, selection of health effects, data processing, and construction of indicators. RESULTS: The literature review concerned 51 articles. The use of self-reported health indicators allowed the studies to take into account the health concerns and complaints of populations exposed to environmental pollution. Various indicators of self-reported health were used in the studies. They measured physical, psychological and general dimensions of health. Standardized questionnaires were used less often than ad hoc questionnaires (78% of studies) developed to fit the needs of a given study. Three standardized questionnaires were used more frequently: the MOS Short-Form Health Survey (SF-36) to measure general health perceptions, the General Health Questionnaire (GHQ), and the Symptoms Checklist (SCL-90) to measure psychological distress. CONCLUSION: The choice of self-reported health indicators is a compromise between specificity of the studied health issues within a given environment and standardization of the questionnaires used to measure them. Such standardization is necessary to ensure the validity and the reliability of the information collected across time and situations. The psychometric properties of the measuring questionnaires are rarely estimated or verified when they are used.


Assuntos
Poluição Ambiental , Indicadores Básicos de Saúde , Saúde , Características de Residência , Autorrelato , Poluição Ambiental/efeitos adversos , Poluição Ambiental/análise , Poluição Ambiental/estatística & dados numéricos , Saúde/estatística & dados numéricos , Humanos , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Psicometria/métodos , Características de Residência/estatística & dados numéricos , Inquéritos e Questionários
9.
Rev Epidemiol Sante Publique ; 61(4): 388-98, 2013 Aug.
Artigo em Francês | MEDLINE | ID: mdl-23849945

RESUMO

BACKGROUND: Epidemiological studies have investigated the health impacts of local sources of environmental pollution using as an outcome variable self-reported health, reflecting the overall perception interviewed people have of their own health. This work aims at analyzing the advantages and the results of this approach. This second part presents the results of the studies. METHODS: Based on a literature review (51 papers), this article presents an analysis of the contribution of self-reported health to epidemiological studies investigating local sources of environmental pollution. It discusses the associations between self-reported health and exposure variables, and other risk factors that can influence health reporting. RESULTS: Studies using self-reported health showed that local sources can be associated with a wide range of health outcomes, including an impact on mental health and well-being. The perception of pollution, especially sensory information such as odors, affects self-reported health. Attitudes referring to beliefs, worries and personal behaviors concerning the source of pollution have a striking influence on reported health. Attitudes can be used to estimate the reporting bias in a biomedical approach, and also constitute the main explanatory factors in biopsychosocial studies taking into account not only the biological, physical, and chemical factors but also the psychological and social factors at stake in a situation of environmental exposure. CONCLUSION: Studying self-reported health enables a multifactorial approach to health in a context of environmental exposure. This approach is most relevant when conducted within a multidisciplinary framework involving human and social sciences to better understand psychosocial factors. The relevance of this type of approach used as an epidemiological surveillance tool to monitor local situations should be assessed with regard to needs for public health management of these situations.


Assuntos
Poluição Ambiental , Saúde , Características de Residência , Autorrelato , Interpretação Estatística de Dados , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Monitoramento Ambiental/métodos , Monitoramento Ambiental/estatística & dados numéricos , Poluição Ambiental/análise , Poluição Ambiental/estatística & dados numéricos , Estudos Epidemiológicos , Saúde/estatística & dados numéricos , Humanos , Saúde Pública/métodos , Saúde Pública/estatística & dados numéricos , Saúde Pública/tendências , Características de Residência/estatística & dados numéricos
10.
Am J Transplant ; 8(12): 2516-26, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19032222

RESUMO

The use of alpha1,3-galactosyltransferase gene-knockout (GalT-KO) swine donors in discordant xenotransplantation has extended the survival of cardiac xenografts in baboons following transplantation. Eight baboons received heterotopic cardiac xenografts from GalT-KO swine and were treated with a chronic immunosuppressive regimen. The pathologic features of acute humoral xenograft rejection (AHXR), acute cellular xenograft rejection (ACXR) and chronic rejection were assessed in the grafts. No hyperacute rejection developed and one graft survived up to 6 months after transplantation. However, all GalT-KO heart grafts underwent graft failure with AHXR, ACXR and/or chronic rejection. AHXR was characterized by interstitial hemorrhage and multiple thrombi in vessels of various sizes. ACXR was characterized by TUNEL(+) graft cell injury with the infiltration of T cells (including CD3 and TIA-1(+) cytotoxic T cells), CD4(+) cells, CD8(+) cells, macrophages and a small number of B and NK cells. Chronic xenograft vasculopathy, a manifestation of chronic rejection, was characterized by arterial intimal thickening with TUNEL(+) dead cells, antibody and complement deposition, and/or cytotoxic T-cell infiltration. In conclusion, despite the absence of the Gal epitope, acute and chronic antibody and cell-mediated rejection developed in grafts, maintained by chronic immunosupression, presumably due to de novo responses to non-Gal antigens.


Assuntos
Galactosiltransferases/genética , Galactosiltransferases/fisiologia , Rejeição de Enxerto/imunologia , Transplante de Coração/imunologia , Papio hamadryas/imunologia , Porco Miniatura/imunologia , Transplante Heterólogo/imunologia , Animais , Animais Geneticamente Modificados , Formação de Anticorpos/fisiologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Rejeição de Enxerto/patologia , Rejeição de Enxerto/fisiopatologia , Transplante de Coração/patologia , Transplante de Coração/fisiologia , Imunidade Celular/fisiologia , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Células Matadoras Naturais/patologia , Suínos , Porco Miniatura/genética , Trombose/patologia , Transplante Heterólogo/patologia , Transplante Heterólogo/fisiologia , Troponina T/sangue
11.
Transplant Proc ; 40(2): 543-6, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18374124

RESUMO

BACKGROUND: To avoid hyperacute rejection of xeno-organs, alpha1,3-galactosyltransferase knock-out (GalT-KO) pigs have been produced. However, Galalpha1,3Gal (Gal) determinant elimination may expose cryptic carbohydrate antigens and/or generate new antigens that might interfere with the human immune response. METHODS: Glycolipids isolated from small intestine and pancreas of two GalT-KO and one wild-type (WT) pig were tested for immune reactivity with antibodies on thin-layer chromatograms after separation by high-performance liquid chromatography, and selected fractions were analysed by proton NMR spectroscopy. RESULTS: Immunostaining using purified human anti-Gal Abs revealed that tissues from WT animals express large amounts of Gal-antigens whereas GalT-KO tissues lacked these antigens. Proton NMR spectroscopy on small intestine fractions revealed both linear and branched nona- and decaglycosylceramides, respectively, with terminal Gal-epitopes. In corresponding GalT-KO fractions, Gal-epitopes seemed to be replaced by terminal alpha1,2fucoses. Two novel branched blood group H compounds was found in the GalT-KO intestine. CONCLUSIONS: The structural complexity of alphaGal-terminating antigens in the WT organs is very high. Knockout of alpha1,3GalT by gene-targeting results in elimination of Gal-determinants. In addition structurally novel alpha1,2fucose-terminated blood group H compounds were identified in the GalT-KO tissue. These compounds are not expected to be recognized by the human immune system.


Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Galactosiltransferases/deficiência , Glicolipídeos/metabolismo , Intestino Delgado/metabolismo , Organismos Geneticamente Modificados , Pâncreas/metabolismo , Animais , Antígenos/genética , Galactose/genética , Galactosiltransferases/genética , Humanos , Intestino Delgado/enzimologia , Suínos/genética , Porco Miniatura/genética , Transplante Heterólogo
12.
Transplant Proc ; 50(6): 1710-1714, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30056887

RESUMO

INTRODUCTION: Because nearly 30,000 people worldwide become living kidney donors each year, donor safety is of the utmost importance. Recent studies have shown that living kidney donation is associated with an increased relative risk for end-stage renal disease (ESRD). It is essential to determine which donors will be more likely to develop ESRD. One of the risk factors for ESRD in living kidney donors is hypertension and, because there are studies demonstrating that low birthweight is a risk factor for developing hypertension in adult life, we hypothesized that donors with low birthweight may be at higher risk of developing renal disease after donation. METHODS: Seventy-three living kidney donors were examined. Donors were divided into 2 cohorts: a group with low birthweight and group with normal birthweight. We checked whether the donor birthweight has an impact on the outcome of donor renal function and on the development of hypertension. RESULTS: Hypertension was observed statistically more frequent in the group with low birthweight (P = .003). CONCLUSION: Glomerular filtration rate before kidney donation was found to be lower in the low-birthweight group.


Assuntos
Hipertensão/etiologia , Recém-Nascido de Baixo Peso , Falência Renal Crônica/etiologia , Doadores Vivos , Nefrectomia/efeitos adversos , Complicações Pós-Operatórias/etiologia , Coleta de Tecidos e Órgãos/efeitos adversos , Adulto , Feminino , Taxa de Filtração Glomerular , Humanos , Rim/fisiopatologia , Transplante de Rim/efeitos adversos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
13.
Neth J Med ; 75(2): 74-80, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28276326

RESUMO

BACKGROUND: Transplant centres show considerable disagreement in the acceptance of transplant candidates with relative contraindications. The aim of this study is to investigate the outcomes of our patients who had been refused at other centres prior to transplantation at our centre. METHODS: We included patients who had been excluded from transplantation or wait-listing at other centres before referral to our centre. We scored the reasons for refusal at other centres, the type of transplantation procedure, postoperative and long-term complications, patient and graft survival and how these patients experienced the transplantation and quality of life at our centre. All regular patients transplanted in 2010 functioned as a control group for outcome parameters. RESULTS: We identified 23 patients in the period from January 2000 until March 2013. The most frequent reason for the refusal at other centres was obesity. Twenty of the 23 patients (87%) were alive and 19 had a functioning graft (83%) after a median follow-up of 21.0 months after transplantation (range 11.0-48.9). There were significantly more wound-related problems in the study group as compared with the control group (p = 0.029), but their kidney function at one year after transplantation was not significantly different. The patients indicated an improvement of quality of life after transplantation and in general were satisfied with the transplantation. CONCLUSIONS: Patients who had previously had been denied transplantation at other centres generally did well after kidney transplantation with an increased risk of wound complications but a satisfactory graft and patient survival.


Assuntos
Transplante de Rim/estatística & dados numéricos , Recusa em Tratar/estatística & dados numéricos , Adulto , Contraindicações , Feminino , Sobrevivência de Enxerto , Humanos , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
14.
J Heart Lung Transplant ; 24(1): 92-4, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15653386

RESUMO

Troponin T levels have been monitored in baboons (n = 8) undergoing pig heterotopic heart transplantation, and correlated with a decrease in graft contractions and graft survival. Pig heart graft survival was from 12 to 139 days (mean 45, median 33), and graft failure was associated with predominant thrombotic microangiopathy and ischemia, with focal hemorrhage, and edema. An increase in troponin T levels 5 to 6 days before graft failure correlated closely with diminished graft contractions. An increase in troponin T was a reliable indicator that graft dysfunction was occurring.


Assuntos
Transplante de Coração , Transplante Heterotópico , Troponina T/metabolismo , Animais , Biomarcadores/sangue , Isquemia Fria , Sobrevivência de Enxerto/fisiologia , Modelos Cardiovasculares , Isquemia Miocárdica/etiologia , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/fisiopatologia , Papio , Suínos
15.
Transplant Proc ; 37(1): 489-90, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15808685

RESUMO

Hearts from alpha1,3-Galactosyltransferase gene-knockout (GaIT-KO) pigs were transplanted heterotopically into 8 baboons that received an anti-CD154 monoclonal antibody (mAb)-based immunosuppressive regimen and heparin. Three baboons died or were euthanized with beating grafts on 16, 23, and 56 days, respectively, and the remaining 5 grafts functioned for 59-179 days. Hyperacute rejection did not occur, and classical features of acute humoral xenograft or acute cellular rejection were rare. However, thrombotic microangiopathy (TM) developed in all cases; its onset was delayed in 2 baboons that received aspirin. Function of a pig organ in a baboon for a period approaching 6 months has not been reported previously and lends encouragement that the barriers to xenotransplantation will be overcome, but TM requires investigation.


Assuntos
Aspirina/uso terapêutico , Fibrinolíticos/uso terapêutico , Galactosiltransferases/deficiência , Galactosiltransferases/genética , Deleção de Genes , Rejeição de Enxerto/prevenção & controle , Transplante de Coração/métodos , Trombose/prevenção & controle , Transplante Heterólogo/métodos , Animais , Sobrevivência de Enxerto , Papio , Suínos
16.
Transplantation ; 75(11): 1799-806, 2003 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-12811237

RESUMO

BACKGROUND: Spleen transplantation (Tx) between some strains of rodents can lead to donor-specific tolerance either spontaneously or after a short course of immunosuppression. This study developed a surgical technique for spleen Tx in miniature swine to investigate its immunologic impact in a large animal model. METHODS: The preferred surgical technique of spleen Tx (n=8) involved excision of the donor spleen with its vascular pedicle to the aorta and portal vein. Carrel patches of donor aorta and portal vein were anastomosed to the abdominal aorta and inferior vena cava, respectively, of the (splenectomized) recipient. The results in four major histocompatibility complex-matched pairs that were mismatched for the porcine allelic antigen are reported. Two recipients were untreated, one received a 12-day course of cyclosporine A (CsA) alone, and one received thymic irradiation (700 cGy) and CsA. Hematopoietic cell chimerism was followed by fluorescence-activated cell sorter, and graft survival was assessed by histology. RESULTS: Spleen Tx was technically successful. In two untreated pigs, chimerism was detected in the blood (maximum 5% for 17 and 25 days) and lymph nodes (maximum 6% for 28 and 56 days), but both grafts showed histologic rejection by day 28. In two treated pigs, chimerism was present in the blood for 47 and 57 days, and rejection was prevented, with follow-up for 57 and 217 days, respectively. CONCLUSION: Spleen Tx in major histocompatibility complex-matched pairs treated with CsA+/-thymic irradiation results in prolonged chimerism and is associated with the development of in vivo unresponsiveness to the transplanted spleen.


Assuntos
Complexo Principal de Histocompatibilidade/imunologia , Baço/transplante , Esplenectomia/métodos , Animais , Biópsia , Ciclosporina/farmacologia , Citometria de Fluxo , Rejeição de Enxerto/mortalidade , Rejeição de Enxerto/patologia , Células-Tronco Hematopoéticas/citologia , Teste de Histocompatibilidade , Imunossupressores/farmacologia , Complicações Pós-Operatórias , Transplante de Pele/imunologia , Baço/patologia , Porco Miniatura , Doadores de Tecidos , Quimeras de Transplante
17.
Artigo em Inglês | MEDLINE | ID: mdl-12769652

RESUMO

Xenotransplantation, involving the transplantation of pig organs into humans, would resolve the current shortage of organs. It involves, however, a new therapeutic approach to organ transplantation. The presence of natural antibody in primates directed against Galalpha1,3Gal epitopes on pig vascular endothelium leads to early antibody-mediated rejection. An elicited antibody response against the same target epitopes as well as against nonGal antigens intensifies the immune destruction of the organ. Even the minimal deposition of antibody appears to lead to the development of a consumptive coagulopathy that can be fatal. Approaches being investigated to overcome these barriers include depletion and inhibition of natural antibody and complement, and suppression of the elicited T cell-dependent antibody and cellular responses. In addition, however, physiologic incompatibilities between human and pig, particularly those relating to coagulation, may enhance or complicate the immune process, and may require additional therapeutic measures. Current approaches aimed at achieving successful xenotransplantation also include investigation of agents that prevent potential xenozoonotic infection of the recipient. At present, therefore, the therapeutic interventions required to attempt to overcome the barriers to xenotransplantation are multiple. Work indicating progress in the breeding of pigs that do not express the critical Galalpha1,3Gal epitopes, however, is encouraging. The introduction of these pigs may greatly reduce the therapy required, and may ultimately allow the development of methods to induce tolerance to the transplanted pig organ.


Assuntos
Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/efeitos dos fármacos , Transplante Heterólogo/patologia , Animais , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto/imunologia , Humanos , Imunossupressores/uso terapêutico , Transplante Heterólogo/imunologia
18.
J Occup Environ Med ; 42(2): 121-6, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10693071

RESUMO

Personal exposure to nine particulate-phase atmospheric polycyclic aromatic hydrocarbons (PAHs) was assessed among adult non-smoking volunteers in the Grenoble, France, metropolitan area. Using Toxic Equivalency Factors, the associated total atmospheric PAHs lifelong cancer risk was estimated. For 48 hours continuously, 38 subjects without specific occupational exposure to combustion sources carried a PM2.5 particles personal exposure monitor while at home, at work, commuting, or involved in other activities. One phase of the study took place in summer; a second in winter. The monitor set was composed of a pump with an airflow of 4 L.mn-1, a 2.5-micron cyclone, and Teflon filters. The PAH concentrations were determined on seven PM2.5 filters by using high performance liquid chromatography with fluorimetric detection. The predominant PAHs are fluoranthene and indeno pyrene. According to the compound, the personal exposure estimates ranged from 0.13 to 1.67 ng/m3 (yearly means). The average benzo(a) pyrene value is 0.67 ng/m3 (95% confidence interval = 0 to 2.1 ng/m3). Winter exposures were 3 to 25 times greater than summer exposures. The total PAHs lung cancer lifelong risk is 7.8 10(-5) and is driven by exposure to benzo(a) pyrene. Although these risk estimates are 2 to 3 orders of magnitude lower than those associated with specific occupational exposures in the coal or smelter industries, they are of public health concern because they are spread over large urban populations. Further personal exposure studies in adult or children populations are needed.


Assuntos
Exposição Ambiental/efeitos adversos , Neoplasias Pulmonares/induzido quimicamente , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Adulto , Atmosfera/análise , Cromatografia Líquida de Alta Pressão , Monitoramento Ambiental/métodos , Monitoramento Epidemiológico , Feminino , França/epidemiologia , Humanos , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco , Estudos de Amostragem , Estações do Ano , População Urbana
19.
J Occup Environ Med ; 42(4): 391-7, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10774508

RESUMO

The aim of the study was to determine the exposure levels of workers to polycyclic aromatic hydrocarbons on gasworks sites by the measurement of urinary 1-hydroxypyrene. Start-shift and end-shift urine samples were taken every day during an entire week (Monday to Friday), once in November and a second time in June. Four groups of workers were selected according to their activity. Increased exposure was only found among volunteers involved in the remediation of a site, 0.16 to 2.31 mumol/mol creatinine in non-smokers. The median of the non-smoker referent group was 0.02 mumol/mol creatinine (95% confidence interval, 0.01 to 0.04). Smokers had greater exposure levels than non-smokers in every group. Within and between variability was around 200%. Assessment of the exposure of persons on contaminated soil is possible, with the condition that the exposed subjects come in direct contact with the soil.


Assuntos
Exposição Ocupacional/análise , Hidrocarbonetos Policíclicos Aromáticos/urina , Pirenos/metabolismo , Poluentes do Solo/urina , Análise de Variância , Biomarcadores , Feminino , Humanos , Masculino , Exposição Ocupacional/estatística & dados numéricos , Paris , Fumar
20.
Sci Total Environ ; 263(1-3): 47-55, 2000 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-11194162

RESUMO

Population exposure to pollutants in soil is an important public health concern. Difficult to measure, it is usually estimated using multimedia models. Modeling data predict that the skin surface is a predominant exposure route in roughly 15% of the US Superfund sites. Nonetheless, no study has confirmed these predictions. The SOLEX study was an opportunity to study the feasibility of estimating the cutaneous polycyclic aromatic hydrocarbons (PAHs: all 16 of the United States Environmental Protection Agency list) load of workers at three former manufactured gas sites, one of those being under remediation. Over two measurement periods (November 1997 and June 1998), 30 and 28 volunteers, respectively, were equipped for a single day work with five pads that collected soil particles and were placed at the neck, shoulder, wrist, groin, and ankle. Pad contamination was observed for six of the nine workers on the site being remediated but not on other sites. The wrist pad was most often affected, followed by the neck pad, these are, the exposed regions of the body. The PAHs most frequently identified were anthracene, fluoranthene, naphthalene, phenanthrene, and pyrene, at concentrations relatively high. In conclusion, this study showed that estimating skin exposure to soil pollutants is feasible. Secondly, it suggested that only subjects in close contact with the soil had a detectable exposure to PAHs. Extension of this approach to other exposure settings is warranted, especially among children playing in polluted public or private gardens, because their games lead to frequent contact with the soil.


Assuntos
Exposição Ocupacional/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Administração Cutânea , Monitoramento Ambiental/métodos , Estudos de Viabilidade , Indústrias , Saúde Pública
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