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1.
Transplant Proc ; 43(9): 3389-91, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22099803

RESUMO

The aim of the "Transplantation Sans Frontières" (TSF) questionnaire, which was sent to French-speaking centers in 6 different countries and regions, was to establish the current status of organ donation and transplantation in their environments. It was also to examine ways to collaborate and exchange scientific information, teaching, and training in the field of organ transplantation. The French Society of Transplantation and the Agency of Biomedicine already offer specific programs to expand local activities, and the World Health Organization (WHO) regulates them. Therefore, TSF could be a coordinating platform in the near future.


Assuntos
Transplante de Órgãos/métodos , Transplante de Órgãos/normas , Obtenção de Tecidos e Órgãos/métodos , Obtenção de Tecidos e Órgãos/normas , Argélia , Brasil , Canadá , França , Humanos , Cooperação Internacional , Idioma , Moldávia , Transplante de Órgãos/tendências , República da Macedônia do Norte , Sociedades Médicas , Inquéritos e Questionários , Doadores de Tecidos , Obtenção de Tecidos e Órgãos/tendências , Vietnã , Organização Mundial da Saúde
3.
Transplant Proc ; 42(10): 4347-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21168696

RESUMO

We have previously shown that injection of donor-derived Fischer rat OX62+ dendritic cells plus an anti-CD4 monoclonal antibody generates donor-specific CD4+CD25+FoxP3+ regulatory T cells in Lewis rats spleens. The regulatory T cells indefinitely prolonged the survival of skin graft from Fischer rat and abrogated the antidonor antibody response. We have now shown that an injection of 2 × 10(6) donor-derived OX62+ dendritic cells plus 2 mg nondepleting anti-CD4 monoclonal antibody (W3/25) at 28 days before grafting induced indefinite skin graft survival in this combination; whereas an injection on day -1 prolonged it only to 50 days. This effect is donor specific. In both cases, we suppressed the antidonor antibody response. It is likely that the efficacy of this protocol is, at least in part, dependent on induction of donor-specific regulatory T cells, as suggested by previous data. The 28 days necessary to obtain tolerance of allogenic skin grafts may be due to the time required for the host to induce proliferation of donor-specific regulatory T cells.


Assuntos
Anticorpos Monoclonais/imunologia , Formação de Anticorpos , Antígenos CD4/imunologia , Células Dendríticas/citologia , Sobrevivência de Enxerto/imunologia , Transplante de Pele , Baço/citologia , Animais , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew
4.
Transplant Proc ; 41(8): 3320-2, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19857741

RESUMO

Pneumocystis jiroveci pneumonia (PJP) is a severe complication in immunocompromised hosts including transplant recipients. Hypercalcemia (HCa) is not a classic symptom of the disease. However, HCa (mean [SD; range], 2.90 [0.20; 2.71-3.17] mmol/L) was detected in 5 patients with PJP at diagnosis. The HCa was associated with decreased concentrations of circulating parathormone (PTH), from 294 (292) ng/L 3 to 6 months previously to 20 (23.5; 7-53) ng/L. Concentrations of 1,25-(OH)2 vitamin D, measured in 3 patients, were in the high normal range (54.66 [7.23; 225-66] microg/L), whereas 25-(OH) vitamin D concentrations were low (13.9 [2.17; 20-60] microg/L). After treatment with trimethoprim-sulfamethoxazole for 21 days, 4 patients recovered and 1 died. Calcium and PTH concentrations rapidly returned to normal (2.36 [0.05] mmol/L and 89 [29.7] ng/L, respectively) at 2 months after the acute phase of the disease. Although fewer than 10 cases of PJP-associated HCa have been reported to date, it is possible that this association is more frequent than previously thought because our cases were detected during 2 years. As in other granulomatous disease-induced HCa, including fungal infections, it is likely that endogenous extrarenal production of 1-alpha-hydroxylase by activated macrophages and by interferon-gamma involved in granuloma formation results in increased conversion from 25-(OH) vitamin D to 1,25-(OH)2 vitamin D and, consequently, in transient HCa and suppression of PTH secretion. Fortuitous detection of HCa in transplant recipients with pulmonary symptoms must raise suspicion of PJP or fungal infection.


Assuntos
Hipercalcemia/epidemiologia , Transplante de Rim/efeitos adversos , Hormônio Paratireóideo/deficiência , Pneumocystis carinii , Pneumonia por Pneumocystis/epidemiologia , Vitamina D/uso terapêutico , Adulto , Idoso , Creatinina/metabolismo , Di-Hidroxicolecalciferóis/sangue , Feminino , Humanos , Hipercalcemia/sangue , Masculino , Pessoa de Meia-Idade , Pneumonia por Pneumocystis/sangue
5.
Transplant Proc ; 41(8): 3363-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19857750

RESUMO

OBJECTIVE: To examine in a rat model the ability of donor dendritic cells and anti-CD4 monoclonal antibody (mAb) to generate donor-specific CD4+CD25+ regulatory T cells (Tregs) and to evaluate the capacity of these Tregs to prolong skin allograft survival and abrogate the production of donor-specific antibodies after skin grafting. MATERIALS AND METHODS: OX62+ (nonplasmacytoid) splenic dendritic cells were isolated from Fischer rats using magnetic beads and injected (2 x 10(6)) into Lewis rat recipients with or without treatment with a nondepleting anti-CD4 (W3/25) mAb. After 4 weeks, splenic CD4+CD25+FOXP3+ T cells were harvested using magnetic beads from conditioned animals and injected (1 x 10(6)) into naïve Lewis recipients (day 1) before they received a skin graft from a Fischer (n = 4) or a third-party (Norway; n = 4) donor rat. Donor-specific antibodies were detected in recipient blood using flow cytometric cross-matches with donor lymphocytes from day 0 to day 30 after grafting. RESULTS: After injection of conditioned CD4+CD25+FOXP3+ T cells, Lewis recipients accepted skin grafts from Fischer donors indefinitely (>100 days) but rejected third-party skin grafts. Donor-specific antibodies were detected at low levels in only 1 recipient receiving conditioned Tregs before grafting. Naive Tregs did not prolong skin graft survival. CONCLUSION: These preliminary data suggest that splenic dendritic cells in combination with an anti-CD4 mAb induce donor-specific Tregs that indefinitely prolong allogeneic skin graft survival and inhibit donor-specific antibody production. Experiments are under way to determine whether this protocol can inhibit chronic lesions after heart transplantation in this model.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antígenos CD4/imunologia , Células Dendríticas/transplante , Sobrevivência de Enxerto/imunologia , Transplante de Pele/imunologia , Linfócitos T Reguladores/imunologia , Animais , Fatores de Transcrição Forkhead/imunologia , Subunidade alfa de Receptor de Interleucina-2/imunologia , Isoanticorpos/imunologia , Modelos Animais , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew , Transplante Homólogo/imunologia
6.
Transplant Proc ; 41(2): 669-71, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19328952

RESUMO

The aim of this study was to compare the clinical characteristics of recurrent and de novo membranous glomerulopathy (MG) among a cohort of 614 recipients transplanted between 1989 and 2006. Lupus nephritides were excluded. The diagnosis was established on protocol biopsies performed 1, 2, 4, or 8 years after transplantation or because of proteinuria/nephrotic syndrome and/or an increased serum creatinine level. HCV infection, cryoglobulinemia, monoclonal gammopathy, skin cancers, Kaposi sarcoma, diabetes mellitus, anti-HLA antibodies, and graft survival were not significantly different between the groups. Seventeen MG were diagnosed in 15 patients (2.45% of the whole group), including 6 recurrent MG (35%) and 11 de novo MG (75%). Recurrent MG occurred earlier than de novo MG (15.58 +/- 19.13 vs 49.27 +/- 32.71 months). Recipients with de novo MG were more frequently infected with HCV, which seemed to be the main etiologic factor for de novo MG, and may be linked to a Th2 polarization of the immune response.


Assuntos
Glomerulonefrite Membranosa/epidemiologia , Transplante de Rim/efeitos adversos , Quimioterapia Combinada , Feminino , Seguimentos , Sobrevivência de Enxerto , Hepatite C/complicações , Hepatite C/epidemiologia , Humanos , Imunossupressores/uso terapêutico , Falência Renal Crônica/cirurgia , Transplante de Rim/imunologia , Masculino , Recidiva , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo
7.
Transplant Proc ; 39(8): 2586-8, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17954183

RESUMO

This retrospective study was conducted to examine whether the presence of Foxp3+ cells in biopsies of kidney transplants displaying early acute rejection (AR) predicted the outcome of the episode. Seventeen biopsies showing AR included in this study were obtained at 42 +/- 30 days after transplantation. Lesions were graded according to the Banff classification. Foxp3 staining was performed on paraffin-embedded sections with a monoclonal antibody after antigen retrieval. We evaluated relationships between the number and the location of Foxp3+ cells, the type of rejection, and the serum creatinine value at 1 year. Foxp3+ cells were detected in 11 of 17 biopsies with AR (9.5 +/- 13.3 cells/mm(2)). These elements were mixed with other interstitial inflammatory cells. Intraepithelial tubular Foxp3+ cells were seen in 9 biopsies (1.5 +/- 2.5 cells/mm(2)). Foxp3+ cells were associated with borderline lesions (25.5 +/- 22.4/mm(2)); type 1 AR (7.18 +/- 9/mm(2)) and type 2 AR (1.99 +/- 3.46/mm(2)). The average number of cells per field was not different in C4d(+) and C4d(-) AR (6 +/- 8.35 vs 8.5 +/- 14.7/mm(2)). Graft loss within the first year was higher among the group of recipients without Foxp3+ cells (3/6) than those with Foxp3+ cells (0/11). All AR with intraepithelial tubular Foxp3 cells had favorable outcomes. Foxp3 has been proposed as a relevant marker of CD4(+)CD25(+) regulatory T cells. This study showed that Foxp3+ cells can be detected in kidney transplant biopsies with AR. The absence of Foxp3+ cells, especially in epithelial tubular cells, might indicate a poor prognosis following an AR episode.


Assuntos
Fatores de Transcrição Forkhead/análise , Rejeição de Enxerto/patologia , Transplante de Rim/patologia , Doença Aguda , Adulto , Biópsia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência
8.
Transplant Proc ; 39(8): 2595-6, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17954186

RESUMO

Crescentic IgA nephropathy is an uncommon finding in native kidneys (3%-5%) and in renal transplants. This study was performed to determine the frequency of relapsing crescentic IgA nephropathy after kidney transplantation. Over a 15-year period, 42 patients (25 men, 17 women) of age range 17 to 59 years with biopsy-proven IgA nephropathy in their native kidneys were entered into this retrospective study, because they had undergone kidney transplantation and had sequential allograft biopsies during their follow-up. Mean follow-up after transplantation was 8.9 years (range, 1-15 years). In their native kidneys, 5 patients (12%) had more than 20% crescents, and only 2 (5%) had more than 50% of glomeruli involved. As expected, 52.4% of recipients showed recurrent mesangial IgA deposits in their kidney grafts. The 2 patients with diffuse crescentic IgA nephropathy in their native kidneys experienced acute graft dysfunction at 15 and 47 months. Graft biopsy showed recurrent IgA deposits with cellular crescents in 30% and 20% of glomeruli, respectively. Despite corticosteroid pulse therapy, graft failures occurred 2 and 27 months later. No crescentic proliferation was observed during follow-up in any other case. Only 5 other grafts failed because of chronic allograft nephropathy, without any relationship to the relapse of IgA deposits. These data suggested for the first time that only diffuse crescentic IgA nephropathy in the native kidneys was associated with the occurrence of crescents in the kidney transplants, a finding that raises the possibility of a particular subgroup of IgA nephropathies.


Assuntos
Glomerulonefrite por IGA/patologia , Glomerulosclerose Segmentar e Focal/patologia , Transplante de Rim/efeitos adversos , Adolescente , Adulto , Biópsia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos
9.
Clin Nephrol ; 67(1): 38-43, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17269598

RESUMO

Rheumatoid arthritis-induced AA amyloidosis of the bladder is rare, with fewer than 25 cases reported so far. This localization may be life-threatening with a mortality rate of about 60%, most often due to massive hematuria or multiorgan failure as a result of systemic amyloidosis. We report the case of a 72-year-old woman with a long history of rheumatoid arthritis who developed gross hematuria that induced severe anemia. Ultrasonography and tomodensitometry revealed a large mass localized in the upper part of the bladder. Cystoscopy showed a congestive inflammatory area with a large vesicoperitoneal fistula. Biopsies revealed amyloidosis, and immunohistochemical staining of the specimens defined the process as AA amyloidosis. The amyloid deposits were also found in the rectum, duodenum, uterus and kidneys. This case of rheumatoid arthritis-induced AA amyloidosis of the bladder is characterized by its pseudotumoral aspect and the existence ofa vesico-peritoneal fistula: only 2 cases have been reported so far. Treatment was symptomatic, and the patient died from cachexia. The pseudotumoral forms of AA amyloidosis, including amyloidosis of the bladder, deserve an early correct diagnosis. Otherwise, an incorrect diagnosis, especially cancer, may prompt inappropriate treatments.


Assuntos
Amiloidose/etiologia , Artrite Reumatoide/complicações , Doenças Peritoneais/etiologia , Doenças da Bexiga Urinária/etiologia , Fístula da Bexiga Urinária/etiologia , Idoso , Feminino , Fístula , Humanos
10.
Transplant Proc ; 38(7): 2306-7, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16980073

RESUMO

Posttransplant appearance of donor-specific anti-HLA antibodies is correlated with poor graft survival. Herein, we have provided evidence that an HLA-DRB1*0101 kidney allograft recipent developed anti-DR103 antibody after receiving a transplant from a HLA-DRB1*0103 cadaveric donor, resulting in graft loss. HLA-DRB1*0103 is a rare allele in Caucasian populations. It differs from DRB1*0101 only by three amino-acid substitutions and may play a central role in allorecognition. Nevertheless, our data showed that it induced alloimmunization in a DRB1*0101 recipient. Therefore, this new possibility of immunization must be taken into account before transplantation as well as after grafting.


Assuntos
Antígenos HLA-DR/imunologia , Antígeno HLA-DR1/imunologia , Transplante de Rim/imunologia , Anticorpos/sangue , Cadáver , Feminino , Sobrevivência de Enxerto/imunologia , Antígenos HLA/imunologia , Cadeias HLA-DRB1 , Humanos , Imunização , Falência Renal Crônica/cirurgia , Pessoa de Meia-Idade , Transplante Homólogo/imunologia
11.
Transplant Proc ; 38(7): 2327-9, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16980081

RESUMO

The aim of this study was to determine the expression of transforming growth factor-beta (TGFbeta)-1 and type I TGFbeta-receptor on sequential biopsies from renal transplants with and without chronic allograft nephropathy. Twenty-four renal transplant recipients entered the study. They underwent sequential biopsies performed before (T1: 1.44 +/- 1.2 months) and 6 months after (T2: 15.96 +/- 7.2 months) transplantation. Lesions were graded according to the criteria of the Banff classification. C4d was detected by fluorescence microscopy. Immunohistochemistry was performed in order to identify cells expressing TGFbeta-1 and type I TGFbeta-receptor. In normal renal tissue (n = 4), TGFbeta-1 is expressed by tubular epithelial cells and endothelial cells lining glomerular and peritubular capillaries, whereas type 1 TGFbeta-receptor is expressed by tubular epithelial cells and smooth muscle cells in the media of arteries. In recipients with chronic allograft nephropathy (group 1, n = 14), diffuse epithelial expression of both molecules was found in more patients at T2 than at T1 (42.8% vs 21.4%). In contrast, this pattern of expression remained stable or decreased over time in recipients with long-term normal transplants (group 2, n = 10). Furthermore, type 1 TGFbeta-receptor was detected on the smooth muscle cells of arteries in 12/14 (85.7%) of recipients in group 1 and only in 4/9 (44.4%) of recipients in group 2. No relationship was noticed with regard to C4d deposits. These data suggest that the synthesis of TGFbeta-1 and type I TGFbeta-receptor increases over time in recipients developing chronic allograft nephropathy. Further studies are in progress in order to quantify mRNA of both molecules with real-time polymerase chain reaction.


Assuntos
Receptores de Ativinas Tipo I/genética , Transplante de Rim/patologia , Receptores de Fatores de Crescimento Transformadores beta/genética , Fator de Crescimento Transformador beta1/genética , Biópsia , Doença Crônica , Seguimentos , Humanos , Transplante de Rim/fisiologia , Músculo Liso Vascular/imunologia , Músculo Liso Vascular/patologia , Complicações Pós-Operatórias/imunologia , Complicações Pós-Operatórias/patologia , Proteínas Serina-Treonina Quinases , Receptor do Fator de Crescimento Transformador beta Tipo I , Circulação Renal , Fatores de Tempo , Urotélio/imunologia , Urotélio/patologia
12.
Transplant Proc ; 38(7): 2349-51, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16980086

RESUMO

The aim of this work was to study cellular chimerism achieved in lymphoid tissues and production of antidonor lymphocyte antibodies after injection of splenic dendritic cells (DCs) from Fischer F344 rats to Lewis recipients, a model of chronic rejection. DCs isolated from the spleen expressed OX62 (95%), CD80 (70%), and CD86 (80%). Two doses of these nonplasmacytoid splenic DCs from Fischer rats (2 x 10(6) and 5 x 10(6)), which had been labeled ex vivo with a TRITC fluorochrome (PKH26), were injected to Lewis recipients. Using fluorescence microscopy TRITC positive cells were localized at day 15 and day 45 in frozen sections from spleen, thymus, mesenteric lymph nodes, heart, liver, kidney, and skin (n = 5 per group). Donor-specific antibodies were sought with flow cytometric crossmatches in serum samples taken at 7, 15, 30, and 45 days. TRITC-positive DCs were essentially localized in the spleen, the thymus, and lymph nodes of Lewis recipients. The majority of DCs were detected in the spleen (14.9 +/- 3.3 and 14.3 +/- 0.9 DCs/per high power field respectively at day 45). A significant number of DCs was also detected in the thymus and mesenteric lymph nodes at both times. Only some scattered TRITC-positive cells were observed in other organs. The number of DCs was stable over time and did not depend on the injected dose. A positive flow cytometric cross-match was observed at day 30 in all recipients independent of the injected dose. These data showed that 2 x 10(6) mature, nonplasmocytoid DCs from F344 rats injected to Lewis recipients induced stable chimerism in primary and secondary lymphoid organs and a humoral response to donor antigens.


Assuntos
Células Dendríticas/transplante , Rejeição de Enxerto/imunologia , Baço/imunologia , Quimeras de Transplante/imunologia , Transplante Homólogo/imunologia , Animais , Formação de Anticorpos , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Antígeno B7-1/análise , Modelos Animais de Doenças , Indicadores e Reagentes , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew , Rodaminas
13.
Am J Transplant ; 6(3): 632-5, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16468976

RESUMO

Hereditary systemic amyloidosis comprises several autosomal dominant diseases caused by mutations in a number of plasma proteins, including the fibrinogen Aalpha-chain. Four mutations in the fibrinogen Aalpha-chain that are able to induce amyloidosis have been identified so far, the most common being the Glu526Val mutation. We have observed a family in which the father and his son reached end-stage renal failure because of renal amyloidosis induced by a frame-shift mutation in the fibrinogen Aalpha-chain gene producing a novel amyloid protein. Two kidney transplantations in the father and one in the son resulted in fast graft loss caused by recurrence of amyloid deposition. We then performed hepatorenal transplantation in the son. Three years later, liver and kidney functions are normal without recurrence of amyloid deposition. This case, together with three others with the Glu526Val mutation in the extensive literature, suggests that liver transplantation can cure hereditary fibrinogen amyloidosis, whatever the mutation may be.


Assuntos
Amiloidose Familiar/cirurgia , DNA/genética , Fibrinogênio/genética , Mutação da Fase de Leitura , Transplante de Rim/métodos , Transplante de Fígado/métodos , Adulto , Amiloidose Familiar/genética , Amiloidose Familiar/patologia , Biópsia , Seguimentos , Humanos , Transplante de Rim/patologia , Transplante de Fígado/patologia , Masculino
14.
Transplant Proc ; 37(6): 2892-3, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16182846

RESUMO

Donor-specific antibodies may play an important role in the development of chronic allograft rejection process. However, the mechanisms leading to intimal vascular proliferation and fibrosis remain poorly understood. The aim of this study was to examine whether donor-specific HLA antibodies induce overexpression of tissue factor (TF) by endothelial cells. HLA typed human umbilical vein endothelial cells (HUVEC) were incubated for 1 to 12 hours with LPS (10 microg/mL), and increasing concentrations (1 to 500 microg/mL) of anti-HLA A1 antibody specific for an antigen expressed by HUVEC and of an anti-HLA A2 antibody for which A2 was not expressed by the HUVEC. Expression of TF mRNA transcripts was quantified using real time Q-RT PCR and TF activity was tested in cell lysates of cultured HUVEC using a chromogenic TF activity assay. HUVEC-specific anti-HLA A1 antibody at low concentrations (10 microg/mL) induced both a significant increase of TF mRNA transcripts after 1 hour of incubation and TF activity after 3 hours incubation compared to incubation with medium alone or with the nonspecific anti-HLA A2 antibody (n = 4 for all experiments, P < .05). These data show for the first time that specific anti-HLA antibody can induce overexpression of TF on endothelial cells. TF, a transmembrane glycoprotein involved not only in the onset of the coagulation cascade, but also in cell proliferation and anti-apoptotic processes, may play a role in the development of alloantibody-induced chronic rejection.


Assuntos
Endotélio Vascular/fisiologia , Antígeno HLA-A2/imunologia , Tromboplastina/genética , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/imunologia , Regulação da Expressão Gênica/imunologia , Humanos , Isoanticorpos/farmacologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Veias Umbilicais
15.
J Soc Biol ; 195(4): 431-5, 2001.
Artigo em Francês | MEDLINE | ID: mdl-11938561

RESUMO

Using a fully mismatched model recipient Lewis-donor Wistar-Furth rats, we showed that the association donor mature (spleen) dendritic cells with a non depleting anti-CD4 monoclonal antibody can induce a more pronounced decrease of alloreactivity in mixed splenocyte reaction than anti-CD4 alone. These results are observed in vitro and 30 days after injection to the Lewis rats. Such data suggest that anti-CD4 monoclonal antibody can guide mature dendritic cells, usually involved in acute rejection, towards tolerance. The mechanisms are still to be resolved.


Assuntos
Anticorpos Monoclonais/metabolismo , Antígenos CD4/imunologia , Células Dendríticas/imunologia , Isoantígenos/imunologia , Animais , Rejeição de Enxerto , Masculino , Ratos , Ratos Endogâmicos Lew , Ratos Endogâmicos WF , Baço/imunologia
16.
Cardiovasc Res ; 47(3): 618-23, 2000 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-10963735

RESUMO

OBJECTIVE: The high incidence of cardiovascular diseases in chronic renal failure (CRF) and hemodialyzed (HD) patients is now well established and the involvement of oxidative stress has been hypothesized in these phenomena. The aim of our study was to evaluate the level of oxidative stress in healthy controls (CTL) compared with CRF and HD patients before (pre-HD) and after (post-HD) the dialysis session, carried out on a high biocompatible polyacrylonitrile membrane AN69. METHODS: Several indicators of the extracellular redox status were evaluated in plasma. The ascorbyl free radical (AFR) was directly measured using electron spin resonance spectroscopy (ESR) and expressed with respect to the vitamin C level to obtain a direct index of oxidative stress. Indirect plasma parameters such as vitamin E, thiol and uric acid levels were also quantified. The plasma antioxidant status (PAS) was evaluated by the allophycocyanin test. Nitric oxide (NO) stable-end metabolites: nitrites and nitrates (NO(x)), were measured in plasma. RESULTS: In CRF patients, vitamin C and thiol levels were low, and the AFR/vitamin C ratio high compared with the CTL. On the other hand, PAS and uric acid levels were shown to be higher in CRF patients. After the dialysis session, vitamin C level decreased and AFR/vitamin C ratio increased. The thiol levels were shown to be increased, in return PAS and uric acid levels were significantly lower after the dialysis session. NO(x) levels rose during CRF, but were significantly decreased after the dialysis procedure. No differences in vitamin E status were observed between CTL, CRF and HD patients. CONCLUSION: Our study demonstrates that profound disturbances in the extracellular redox system occur during the course of chronic renal failure and hemodialysis, and may provide an explanation for the cardiovascular complications in these patients.


Assuntos
Antioxidantes/análise , Doenças Cardiovasculares/etiologia , Falência Renal Crônica/complicações , Idoso , Análise de Variância , Ácido Ascórbico/sangue , Doenças Cardiovasculares/sangue , Estudos de Casos e Controles , Colesterol/sangue , Espectroscopia de Ressonância de Spin Eletrônica , Feminino , Radicais Livres/análise , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Nitratos/sangue , Óxido Nítrico/sangue , Nitritos/sangue , Estresse Oxidativo , Diálise Renal , Fatores de Risco , Compostos de Sulfidrila/análise , Ácido Úrico/sangue , Vitamina E/sangue
18.
Transplantation ; 67(10): 1376-8, 1999 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-10360595

RESUMO

Foscarnet nephrotoxicity has been reported to be associated with acute tubulointerstitial nephritis. Crystals in glomerular capillary lumens have also been observed in patients with acquired immunodeficiency syndrome who were treated with foscarnet for cytomegalovirus disease. We describe a kidney transplant recipient who developed a nephrotic syndrome with microscopic hematuria and nonoliguric acute renal failure within 15 days after starting foscarnet therapy for cytomegalovirus infection. A kidney biopsy specimen showed the presence of crystals in all glomeruli and in proximal tubules. Fourier transform infrared microscopy analysis demonstrated that crystals were made from several forms of foscarnet salts: mixed calcium and sodium salts, and unchanged trisodium foscarnet salts. Renal function and proteinuria spontaneously improved, and a second transplant biopsy performed 8 months after the first one revealed fibrotic organization of half of the glomeruli and of interstitial tissue, and crystal vanishing. We were thus able to provide proof of the possible precipitation of foscarnet in a transplanted kidney.


Assuntos
Nefropatia Associada a AIDS/induzido quimicamente , Injúria Renal Aguda/complicações , Antivirais/efeitos adversos , Foscarnet/efeitos adversos , Glomerulonefrite/induzido quimicamente , Transplante de Rim , Infecções por Citomegalovirus/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome Nefrótica/complicações
19.
Histopathology ; 34(4): 365-9, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10231404

RESUMO

AIMS: Foscarnet is an antiviral agent used to treat cytomegalovirus infection in AIDS patients and in transplant recipients. In most cases, foscarnet induces reversible tubulo-interstitial lesions which can be avoided by correct hydration. We report the first case of crystal foscarnet precipitation within glomerular capillaries in a renal transplant. METHODS AND RESULTS: The recipient, a 49-year-old man, developed a nephrotic syndrome with haematuria and an acute renal failure after foscarnet therapy for cytomegalovirus (CMV) infection. The polarization examination of the first graft biopsy revealed the presence of birefringent crystals within glomeruli and tubules. Infrared analysis attested to the presence of trisodium foscarnet salts and mixed sodium calcium salts coloured by Von Kossa's reaction. A second biopsy showed glomerular sclerosis, interstitial fibrosis, tubular atrophy and crystal vanishing. Polymerase chain reaction (PCR) in situ applied to this biopsy confirmed the diagnosis of cytomegalovirus infection. CONCLUSIONS: These adverse effects might be the result of a toxic synergy between foscarnet and other drugs. In cases with crystalline precipitation, graft biopsy remains the best mean of diagnosis and follow-up of glomerular damage.


Assuntos
Foscarnet/efeitos adversos , Nefropatias/induzido quimicamente , Glomérulos Renais/patologia , Transplante de Rim , Biópsia , Birrefringência , Cristalização , Infecções por Citomegalovirus/tratamento farmacológico , Humanos , Nefropatias/patologia , Masculino , Pessoa de Meia-Idade
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