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1.
Am J Transplant ; 15(7): 1805-16, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25766876

RESUMO

Cytomegalovirus accelerates transplant vascular sclerosis (TVS) and chronic rejection (CR) in solid organ transplants; however, the mechanisms involved are unclear. We determined the efficacy of a CMV vaccine in preventing CMV-accelerated rat cardiac allograft rejection in naïve recipients of CMV+ donor hearts. F344 donor rats were infected with RCMV 5 days prior to heterotopic cardiac transplantation into CMV-naïve or H2 O2 -inactivated RCMV-vaccinated Lewis recipients. Recipients of RCMV-infected donor hearts rejected at POD59, whereas vaccinated recipients exhibited a significantly prolonged time to rejection-POD97, similar to recipients of uninfected donor hearts (POD108). Although all of the donor hearts were preinfected, the vaccinated recipients had lower graft and PBMC viral loads at POD 7 compared to unvaccinated controls. Adoptive T cell and passive antibody transfers from vaccinated Lewis rats into naïve recipients demonstrate that both T-cell and B-cell arms of the adaptive immune response provide protection against CMV-accelerated rejection. Similar findings were obtained when testing three different adjuvants in passive transfer experiments. We have determined that the timing of the vaccine prior to transplantation and the specific adjuvant play critical roles in mediating anti-viral responses and promoting graft survival. CMV vaccination prior to transplantation may effectively increase graft survival.


Assuntos
Infecções por Citomegalovirus/prevenção & controle , Vacinas contra Citomegalovirus/administração & dosagem , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/imunologia , Transplante de Coração/efeitos adversos , Muromegalovirus/imunologia , Aloenxertos , Animais , Western Blotting , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/microbiologia , Ensaio de Imunoadsorção Enzimática , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Reação em Cadeia da Polimerase , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew , Doadores de Tecidos , Transplantados
2.
Am J Transplant ; 11(1): 45-55, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21199347

RESUMO

Human cytomegalovirus (HCMV) infection is associated with the acceleration of transplant vascular sclerosis (TVS) and chronic allograft rejection (CR). HCMV-negative recipients of latently HCMV infected donor grafts are at highest risk for developing CMV disease. Using a rat heart transplant CR model, we have previously shown that acute rat CMV (RCMV) infection following transplantation significantly accelerates both TVS and CR. Here, we report that RCMV-naïve recipients of heart allografts from latently RCMV-infected donors undergo acceleration of CR with similar kinetics as acutely infected recipients. In contrast to acutely infected recipients, treatment of recipients of latently infected donor hearts with ganciclovir did not prevent CR or TVS. We observed the formation of tertiary lymphoid structures (TLOs) containing macrophages and T cells in latently infected hearts prior to transplantation but not in uninfected rats. Moreover, pathway analysis of gene expression data from allografts from latently infected donors indicated an early and sustained production of TLO-associated genes compared to allografts from uninfected donors. We conclude that RCMV-induced TLO formation and alteration of donor tissue T cell profiles prior to transplantation in part mediate the ganciclovir-insensitive rejection of latently infected donor allografts transplanted into naïve recipients by providing a scaffold for immune activation.


Assuntos
Infecções por Citomegalovirus/imunologia , Transplante de Coração/imunologia , Animais , Arteriosclerose/complicações , Arteriosclerose/imunologia , Citomegalovirus/fisiologia , Ganciclovir/uso terapêutico , Rejeição de Enxerto/imunologia , Humanos , Tecido Linfoide/fisiologia , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew
3.
Am J Transplant ; 9(9): 1988-2003, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19563332

RESUMO

No official document has been published for primary care physicians regarding the management of liver transplant patients. With no official source of reference, primary care physicians often question their care of these patients. The following guidelines have been approved by the American Society of Transplantation and represent the position of the association. The data presented are based on formal review and analysis of published literature in the field and the clinical experience of the authors. These guidelines address drug interactions and side effects of immunosuppressive agents, allograft dysfunction, renal dysfunction, metabolic disorders, preventive medicine, malignancies, disability and productivity in the workforce, issues specific to pregnancy and sexual function, and pediatric patient concerns. These guidelines are intended to provide a bridge between transplant centers and primary care physicians in the long-term management of the liver transplant patient.


Assuntos
Imunossupressores/uso terapêutico , Transplante de Fígado/métodos , Cuidados Pós-Operatórios , Atenção Primária à Saúde/métodos , Atenção Primária à Saúde/normas , Adulto , Criança , Rejeição de Enxerto , Humanos , Terapia de Imunossupressão , Nefropatias/patologia , Nefropatias/terapia , Hepatopatias/patologia , Hepatopatias/terapia , Recidiva , Fatores de Tempo , Resultado do Tratamento
4.
Curr Top Microbiol Immunol ; 325: 397-415, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18637518

RESUMO

Human cytomegalovirus (HCMV) is associated with the acceleration of a number of vascular diseases such as atherosclerosis, restenosis, and transplant vascular sclerosis (TVS). All of these diseases are the result of either mechanical or immune-mediated injury followed by inflammation and subsequent smooth muscle cell (SMC) migration from the vessel media to the intima and proliferation that culminates in vessel narrowing. A number of epidemiological and animal studies have demonstrated that CMV significantly accelerates TVS and chronic rejection (CR) in solid organ allografts. In addition, treatment of human recipients and animals alike with the antiviral drug ganciclovir results in prolonged survival of the allograft, indicating that CMV replication is a requirement for acceleration of disease. However, although virus persists in the allograft throughout the course of disease, the number of directly infected cells does not account for the global effects that the virus has on the acceleration of TVS and CR. Recent investigations of up- and downregulated cellular genes in infected allografts in comparison to native heart has demonstrated that rat CMV (RCMV) upregulates genes involved in wound healing (WH) and angiogenesis (AG). Consistent with this result, we have found that supernatants from HCMV-infected cells (HCMV secretome) induce WH and AG using in vitro models. Taken together, these findings suggest that one mechanism for HCMV acceleration of TVS is mediated through induction of secreted cytokines and growth factors from virus-infected cells that promote WH and AG in the allograft, resulting in the acceleration of TVS. We review here the ability of CMV infection to alter the local environment by producing cellular factors that act in a paracrine fashion to enhance WH and AG processes associated with the development of vascular disease, which accelerates chronic allograft rejection.


Assuntos
Infecções por Citomegalovirus/patologia , Infecções por Citomegalovirus/virologia , Citomegalovirus/fisiologia , Doenças Vasculares/virologia , Animais , Citocinas/biossíntese , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Ratos , Esclerose
5.
Am J Transplant ; 8(2): 277-87, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18093265

RESUMO

Human cytomegalovirus (HCMV) accelerates transplant vascular sclerosis (TVS), a consequence of angiogenesis (AG) and wound repair (WR). While HCMV can be localized to TVS lesions, the low number of infected cells suggests a global effect on target tissues. We used microarray analysis followed by real-time-polymerase chain reaction (RT-PCR) in an RCMV-accelerated TVS rat cardiac transplant model to determine whether CMV activates host WR and AG factors. Dysregulated cellular genes in allografts from RCMV-infected recipients were compared to those from uninfected recipients and native hearts. We demonstrated that RCMV upregulates the genes involved in WR and AG, which was highest during the critical time of TVS acceleration (21-28 days). Using a standard in vitro AG assay, virus and serum-free supernatants collected at 48 h postinfection significantly induced endothelial cell (EC) migration, branching and tubule formation compared to supernatants from mock-infected cells. Supernatants from ultraviolet (UV)-inactivated RCMV-infected cells failed to induce AG, indicating that virus replication is required. Upregulation of WR and AG genes occurs during the critical period of CMV-accelerated TVS. Targeting these genes may prevent this process and improve allograft survival.


Assuntos
Doença da Artéria Coronariana/complicações , Infecções por Citomegalovirus/complicações , Transplante de Coração/fisiologia , Neovascularização Fisiológica , Cicatrização , Animais , Doença da Artéria Coronariana/virologia , Citomegalovirus , Modelos Animais de Doenças , Genoma , Masculino , Metaloproteinases da Matriz/genética , Análise de Sequência com Séries de Oligonucleotídeos , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transplante Homólogo
6.
Transplant Proc ; 49(2): 322-325, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28219592

RESUMO

BACKGROUND: The recent outbreak of acute liver failure caused by herbal/dietary supplements (HDS) in Hawaii prompted evaluation of those patients who underwent emergency liver transplantation (LT) for HDS in the United States. METHODS: We queried the Scientific Registry of Transplant Recipients (2003-2015) to identify patients who underwent urgent LT for acute hepatic necrosis (AHN) and identified those with HDS use. This group of patients was then characterized. RESULTS: Of 2408 adult cases, 625 were characterized as a drug-induced liver injury. The majority of cases (n = 300) were due to acetaminophen toxicity, but the fourth highest category was due to HDS (n = 21). Of these 21 cases caused by HDS, 13 did not list the specific agent responsible, mean age was 36 years, and all cases occurred after 2007. There probably are more cases because 25% of all LT cases in the study did not list a specific reason for liver failure and 20% of all drug-induced liver failure did not list a specific drug. CONCLUSIONS: Herbal/supplement use is the fourth most common cause of drug-induced AHN requiring LT, albeit an underestimation of the problem. Detailed questioning of patients and their support systems regarding herbal/supplement use and better reporting are imperative to further define this problem and identify products that have the potential to lead to liver failure.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas/cirurgia , Suplementos Nutricionais/efeitos adversos , Transplante de Fígado/métodos , Preparações de Plantas/efeitos adversos , Adulto , Anti-Inflamatórios não Esteroides/efeitos adversos , Doença Hepática Crônica Induzida por Substâncias e Drogas/etiologia , Tratamento de Emergência , Feminino , Humanos , Falência Hepática Aguda/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estados Unidos , Adulto Jovem
7.
Transplant Proc ; 38(10): 3214-20, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17175227

RESUMO

BACKGROUND: Studies have shown that rat cytomegalovirus (RCMV) infection accelerates transplant vascular sclerosis (TVS) in rat heart and small bowel allotransplants. In these models, RCMV-accelerated TVS results from increased graft infiltration of inflammatory cells through up-regulation of chemokine expression. The aim of this study was to determine if RCMV infection accelerates renal transplant chronic allograft nephropathy (CAN), and the role of chemokines in this process. METHODS: F344 kidneys were transplanted into Lewis recipients with and without RCMV infection. To monitor CAN, serum creatinine (Cr) levels were measured starting at 4 weeks posttransplantation. At 7 and 21 days, and at terminal rejection, grafts were examined for histologic changes, inflammatory cell infiltrates, viral load, and chemokine expression profiles. RESULTS: By week 8, serum Cr showed significant elevation (P < .01) in the RCMV-infected group vs uninfected group, and remained significantly elevated through the end of the study. RCMV+ renal allografts had significant inflammatory cell infiltration and increased CAN at postoperative day (POD) 28. The CC chemokines RANTES, MCP-1, and MIP-1alpha, and the CXC chemokine IP-10 were up-regulated in RCMV-infected vs uninfected allografts. IP-10 was significantly up-regulated early in the process, whereas RANTES and MCP-1 were induced at a later time. CONCLUSIONS: RCMV infection accelerates CAN, with associated graft inflammatory infiltrates, which is paralleled by an increase in expression of CC and CXC chemokines. Our findings suggest that the early induction of IP-10 in the infected allografts promotes alterations in T-cell and monocyte migration to the graft, which initiates accelerated inflammatory and fibrotic changes associated with CAN.


Assuntos
Quimiocinas/biossíntese , Infecções por Citomegalovirus/imunologia , Citomegalovirus/patogenicidade , Transplante de Rim/patologia , Animais , Imuno-Histoquímica , Modelos Animais , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew , Transplante Homólogo
8.
J Leukoc Biol ; 44(5): 361-6, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2846727

RESUMO

We evaluated the ability of normal human peripheral blood monocytes and polymorphonuclear leucocytes (PMNL) isolated from patients with acquired immunodeficiency syndrome (AIDS) or AIDS-related conditions (ARC) to migrate toward a chemoattractant. Migration in blind-well chambers was compared to that under agarose. Chemotaxis results obtained from both assays for PMNL were similar, however there was a difference in the results for monocyte chemotaxis. PMNL isolated from patients with AIDS, but not ARC, exhibited decreased spontaneous and directed chemotaxis when assessed in blind-well chambers and under agarose. Spontaneous and directed chemotaxis in blind-well chambers of AIDS patients' monocytes was normal. Directed migration of monocytes from ARC patients was greater than that of control, but spontaneous migration was comparable. Under agarose, spontaneous migration was depressed in monocytes of AIDS patients, while migration toward the attractant was depressed in those of ARC patients.


Assuntos
Complexo Relacionado com a AIDS/imunologia , Síndrome da Imunodeficiência Adquirida/imunologia , Quimiotaxia de Leucócito , Monócitos/imunologia , Neutrófilos/imunologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Superóxidos/metabolismo
9.
AIDS ; 12(12): 1545-9, 1998 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-9727577

RESUMO

OBJECTIVE: To evaluate the sensitivity and specificity of an RNA detection assay for diagnosing perinatal HIV infection. METHODS: Plasma and serum specimens taken during the first 3 months of life from HIV-infected and uninfected children enrolled in a cohort study were assayed for HIV RNA using the qualitative nucleic acid sequence-based amplification (NASBA) kit. Sensitivity, specificity, and predictive values were calculated. NASBA results from infected children were compared with DNA PCR results from the same blood samples. Autoantibody patterns of suspected false-positive specimens were compared with those of subsequent specimens from the same child to exclude specimen labelling errors. RESULTS: Amongst 131 specimens from 105 HIV-infected children, the sensitivity of the qualitative NASBA assay was 13 out of 34 [38%; 95% confidence interval (CI), 22-56] at < 7 days, 56 out of 58 (97%; 95% CI, 88-100) at 7-41 days, and 37 out of 39 (95%; 95% CI, 83-99) at 42-93 days of life. Of 252 specimens from 206 uninfected children, six tested positive and one tested indeterminate by NASBA. Four of these positive specimens had discordant autoantibody patterns suggesting mislabelling; excluding these, the test specificity was 245 out of 248 (99%; 95% CI, 97-100). Amongst 128 paired specimens from infected children, NASBA results were more often positive than those from DNA PCR (103 versus 92; P=0.01). Amongst infants with specimens drawn in the first week of life, the proportion born after > 4 h of membrane rupture was greater amongst those testing negative (81%) than those testing positive (46%; P=0.05). CONCLUSIONS: The qualitative NASBA RNA assay is highly specific and more sensitive than DNA PCR. Qualitative RNA assays may be useful for diagnosing and excluding perinatal HIV infection in children after the first week of life for such purposes as initiating antiretroviral therapy and other treatment, resolving parental uncertainty, determining timing of transmission, and providing endpoints for intervention trials.


Assuntos
Infecções por HIV/diagnóstico , HIV-1/genética , Reação em Cadeia da Polimerase/métodos , RNA Viral/sangue , Estudos de Coortes , Estudos de Avaliação como Assunto , Infecções por HIV/transmissão , Humanos , Lactente , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Valor Preditivo dos Testes , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade
10.
J Immunol Methods ; 160(2): 215-8, 1993 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-8459108

RESUMO

Reagents that lyse red blood cells and fix white blood cells were tested for their ability to inactivate cell-associated human immunodeficiency virus (HIV). Whole blood was spiked with cells from an HIV-positive cell line (H9), lysed, and fixed. The cell preparations were then cocultured with T cell blasts in serial ten-fold dilutions to rescue infectious virus and measure viral titer. All commercial lysing and fixing reagents tested inactivated cell-associated HIV by 3-5 logs, while ammonium chloride had little effect. Although an additional incubation with 1% formaldehyde for 30 min did not increase the effectiveness of the commercial lysing/fixing reagents, it did inactivate cell-associated HIV in blood treated with ammonium chloride.


Assuntos
Citometria de Fluxo/métodos , Infecções por HIV/microbiologia , HIV/efeitos dos fármacos , Imunofenotipagem/métodos , Morte Celular , Células Cultivadas , Fixadores , Formaldeído/química , Humanos , Técnicas In Vitro
11.
Transplantation ; 64(5): 721-6, 1997 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-9311709

RESUMO

BACKGROUND: Despite recent advances in diagnosis and treatment, cytomegalovirus (CMV) infection continues to be a common cause of morbidity in liver transplant (LT) recipients. Because CMV infection suppresses cell-mediated immunity, which seems to be important in neutralizing hepatitis C virus (HCV) infection, we assessed the impact of CMV infection on histopathological HCV recurrence after LT. METHODS: The study group was comprised of 43 consecutive LT recipients with at least 6 months of histologic follow-up. Group 1 consisted of the 8 patients who developed CMV viremia after LT; group 2 comprised the 35 patients without CMV viremia. There was no significant difference with regard to age, initial immunosuppression, incidence of rejection, distribution of HCV genotypes, or mean follow-up between the groups. Semiquantitative histopathologic assessment of allograft hepatitis was performed using the Knodell's score. RESULTS: The mean total Knodell score of the final allograft biopsy was significantly greater in group 1 patients (P=0.016), with most of the difference due to periportal/bridging necrosis (P=0.009) and lobular activity subitem (P=0.01) scores. Half of the CMV viremic patients eventually developed allograft cirrhosis as compared with 11% of the CMV-negative patients (P=0.027). Accordingly, the cirrhosis-free actuarial survival by Kaplan-Meier estimates was significantly diminished in the CMV viremic patients. Glycoprotein B genotype analysis of CMV isolates revealed no significant differences between patients who did and those who did not develop allograft cirrhosis. CONCLUSIONS: After LT for chronic HCV, patients who develop CMV viremia incur a significantly greater risk of severe HCV recurrence.


Assuntos
Infecções por Citomegalovirus/sangue , Antivirais/uso terapêutico , Biópsia , Citomegalovirus/genética , Infecções por Citomegalovirus/prevenção & controle , Ganciclovir/uso terapêutico , Genótipo , Rejeição de Enxerto/mortalidade , Rejeição de Enxerto/prevenção & controle , Hepacivirus/genética , Hepatite C/cirurgia , Humanos , Cirrose Hepática/epidemiologia , Cirrose Hepática/etiologia , Transplante de Fígado/efeitos adversos , Pessoa de Meia-Idade , Fatores de Risco , Fatores de Tempo , Transplante Homólogo/efeitos adversos , Transplante Homólogo/patologia
12.
Transplantation ; 69(7): 1295-303, 2000 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-10798744

RESUMO

BACKGROUND: The major impediment to success in solid organ transplantation is chronic rejection (CR). The characteristic lesion of CR is transplant vascular sclerosis (TVS). Although the mechanism of TVS is thought to have an immunologic basis, in humans immunosuppression does not prevent or reverse it. One possible therapy to prevent TVS is induction of donor-specific tolerance. Bone marrow chimerism has been successful in inducing tolerance in acute and chronic rejection heart and kidney transplant models. The highly immunogenic small bowel (SB) allograft provides a rigorous test of the efficacy of this tolerance regimen. We examined whether induction of tolerance by bone marrow chimerism could prevent TVS in a model of Fisher 344 (F344) to Lewis (LEW) rat SB transplantation. METHODS: Bone marrow chimeras (BMC) were created by transplantation of T-cell-depleted F344 bone marrow into irradiated LEW rats. Chimerism was assessed by flow cytometric method. F344 SB, heterotopically transplanted into the chimeras, was clinically and histologically assessed for CR. F344 SB grafts, transplanted into cyclosporine-A-treated LEW recipients, served as control grafts for CR. RESULTS: Cyclosporine-A-treated LEW rats chronically rejected F344 SB grafts. By contrast, the BMC group demonstrated tolerance and had long-term SB graft survival (>120 days) without TVS. The BMC demonstrated immunocompetence by prompt rejection of third party ACI (RT1av1) SB allografts. CONCLUSIONS: Bone marrow chimerism prevents chronic graft failure secondary to TVS in a model of chronic SB rejection. TVS fails to develop when tolerance is established, suggesting that the mechanisms involved in TVS are, in part, immunologically mediated.


Assuntos
Medula Óssea/fisiologia , Quimera/imunologia , Rejeição de Enxerto/complicações , Tolerância Imunológica/fisiologia , Intestino Delgado/irrigação sanguínea , Intestino Delgado/transplante , Doenças Vasculares/prevenção & controle , Animais , Doença Crônica , Rejeição de Enxerto/patologia , Intestino Delgado/patologia , Masculino , Ratos , Ratos Endogâmicos ACI , Ratos Sprague-Dawley , Esclerose/prevenção & controle , Doenças Vasculares/etiologia , Doenças Vasculares/patologia
13.
Transplantation ; 68(6): 766-79, 1999 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-10515376

RESUMO

BACKGROUND: The major impediment to long-term success in solid organ transplantation is the development of chronic rejection (CR). The vascular lesion of CR, transplant vascular sclerosis (TVS) is characterized by neointimal smooth muscle cell proliferation, and is driven by both immune- and nonimmune-mediated mechanisms. Although the features of chronic heart and kidney allograft rejection have been well characterized, the more immunogenic small bowel allograft has not received similar study. METHODS: F344 small bowel (SB) was transplanted heterotopically into Lewis recipients that were treated with low-dose Cyclosporine A for 15 days. Lewis recipients of F344 or Lewis SB grafts without immunosuppression, served as controls. Grafts were assessed histologically when recipients showed clinical signs of rejection or at predetermined time points. The immunological components involved in the chronic rejection process were evaluated by immunohistochemical staining. RESULTS: All SB allografts (100%) developed histologic evidence of CR Cyclosporine A. TVS was seen in 36 of the 46 (78%) of these allografts. The median time to develop TVS was 45 days. Immunohistochemical staining of chronically rejected grafts showed infiltration predominantly by CD4+ cells and macrophages, uniform up-regulation of class II MHC molecule expression, moderate to intense ICAM-1 staining in grafts harvested at postoperative day 45, and uniform neointimal cell staining for smooth muscle cell alpha-actin in the TVS lesions. CONCLUSIONS: This F344 to Lewis SB transplant model is a useful model that reproduces significant features of CR. The highly immunogenic nature of the SB allografts allows this model to serve as a stringent test for protocols designed to prevent CR.


Assuntos
Intestino Delgado/transplante , Animais , Arteriosclerose/etiologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Ciclosporina/farmacologia , Modelos Animais de Doenças , Fibrose , Rejeição de Enxerto/complicações , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto/efeitos dos fármacos , Sobrevivência de Enxerto/fisiologia , Antígenos de Histocompatibilidade Classe II/imunologia , Imuno-Histoquímica , Intestino Delgado/patologia , Macrófagos/imunologia , Masculino , Oclusão Vascular Mesentérica/etiologia , Mesentério/patologia , Músculo Liso Vascular/citologia , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew , Fatores de Tempo
14.
Transplantation ; 65(2): 193-9, 1998 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-9458013

RESUMO

BACKGROUND: Biliary anastomotic complications remain a major cause of morbidity in liver transplant recipients, ranging between 10% and 50% in large clinical series. An end-to-end choledochocholedochostomy with or without T tube (CDCD EE with T tube and CDCD EE w/o T tube) and a Roux-en Y choledochojejunostomy have been standard methods for biliary drainage. METHODS: The objectives of this retrospective study were to: (1) evaluate the incidence of biliary tract complications using a new method of side-to-side choledochocholedochostomy without T tube (CDCD SS w/o T tube) and (2) compare the results of CDCD SS w/o T tube with those of CDCD EE with T tube and CDCD EE w/o T tube. From September 1991 through June 1996, 279 orthotopic liver transplants were performed in 268 patients and followed through December 1996 (minimum of 6 months' follow-up). A total of 227 CDCD anastomoses in 220 patients were studied (7 retransplants > 30 days): CDCD EE with T tube (n=124), CDCD EE w/o T tube (n=44), and CDCD SS w/o T tube (n=59). RESULTS: Sixty-nine biliary complications were observed in 220 patients (30%). Anastomotic and/or T-tube leaks were seen in 43 patients (19%), and anastomotic strictures were found in 26 patients (12%). Forty patients (18%) required percutaneous or endoscopic stent placement (6%) or surgical interventions (12%). CDCD EE with T tube had the highest incidence of biliary leak requiring rehospitalization but the lowest anastomotic stricture and intervention rate and the lowest 6-month mortality rate. CONCLUSIONS: CDCD EE with T tube was superior to CDCD EE or CDCD SS w/o T tube despite the increased number of rehospitalizations. CDCD SS w/o T tube did not offer significant advantages over conventional biliary anastomotic techniques.


Assuntos
Ductos Biliares Extra-Hepáticos , Coledocostomia/métodos , Transplante de Fígado/métodos , Complicações Pós-Operatórias , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
15.
AIDS Res Hum Retroviruses ; 11(3): 335-42, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7786580

RESUMO

Primary isolates of human immunodeficiency virus type 1 (HIV-1) were obtained by coculture of peripheral blood lymphocytes (PBLs) from HIV-1-infected people with PBLs from uninfected donors. These viral stocks tend to be resistant to neutralization/inactivation by soluble CD4 (sCD4). When these stocks were passed through the T cell line C8166, virus stocks emerged that were sensitive to sCD4. Pre- and post-C8166 stocks maintained their sCD4-resistant and -sensitive phenotypes, respectively, with further passage in PBLs. Pre- and post-C8166 stocks were biologically cloned by two cycles of limiting dilution. The majority (14 of 17) of pre-C8166 clones were sCD4 resistant, and, conversely, the majority of post-C8166 clones (11 of 12) were sensitive to sCD4. Nucleotide and predicted amino acid sequence analysis in the env (gp120) region revealed a limited number of differences between the clones. The only differences that sorted with biological phenotype were in the first constant (C1) region of gp120. Adaptation to growth in C8166 cells and conversion from the sCD4-resistant to the sCD4-sensitive phenotype represent the emergence to prominence of viral species in the pre-C8166 stock that have a replication advantage in C8166 coincident with increased sensitivity to sCD4.


Assuntos
Antígenos CD/fisiologia , Antígenos CD4/fisiologia , Proteína gp120 do Envelope de HIV/genética , Soropositividade para HIV/virologia , HIV-1/fisiologia , Linfócitos/imunologia , Linfócitos/virologia , Sequência de Aminoácidos , Linhagem Celular , Células Cultivadas , DNA Viral/metabolismo , Células Gigantes , HIV-1/isolamento & purificação , HIV-1/patogenicidade , Humanos , Cinética , Masculino , Dados de Sequência Molecular , Fenótipo , Reação em Cadeia da Polimerase , Provírus/genética , Provírus/patogenicidade , Provírus/fisiologia
16.
Curr Drug Targets Infect Disord ; 1(2): 151-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12455411

RESUMO

The human cytomegalovirus (HCMV) has been implicated in the acceleration of vascular disease for some time. The development of vascular disease involves a chronic inflammatory process with many contributing factors, and of these, chemokines and their receptors have recently been identified as key mediators. Interestingly, HCMV encodes four potential chemokine receptors (US27, US28, UL33 and UL78). Of these virally-encoded chemokine receptors, US28 has been the most widely characterized. US28 binds many of the CC-chemokines, and this class of chemokines contributes to the development of vascular disease. Importantly, HCMV infection mediates in vitro SMC migration, which is dependent upon expression of US28 and CC-chemokine binding. US28 and the US28 functional homologues that are capable of inducing the migration of SMC represent potential targets in the treatment of CMV-accelerated vascular disease such as atherosclerosis, restenosis, and transplant vascular sclerosis.


Assuntos
Antivirais/uso terapêutico , Infecções por Citomegalovirus/tratamento farmacológico , Receptores de Quimiocinas/antagonistas & inibidores , Doenças Vasculares/tratamento farmacológico , Proteínas Virais/antagonistas & inibidores , Animais , Movimento Celular/efeitos dos fármacos , Quimiocinas/fisiologia , Modelos Animais de Doenças , Humanos , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Receptores de Quimiocinas/fisiologia , Proteínas Virais/fisiologia
17.
Arch Surg ; 126(10): 1267-70; discussion 1270-1, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1929828

RESUMO

Medical records of 52 human immunodeficiency virus (HIV)-infected patients who underwent a total of 80 anorectal operations from January 1985 to January 1990 were retrospectively reviewed to determined whether anorectal surgical wounds healed in HIV-infected patients and the mean survival time of these patients after surgery. Twenty-four operations were performed in asymptomatic HIV-infected patients, 19 in HIV-infected patients with persistent lymphadenopathy, and 37 in patients with acquired immunodeficiency syndrome. Wounds healed in 49 patients (94%). The mortality rate 30 days after surgery was 2%. There were no major complications. The mean survival time of HIV-infected patients after surgery was 15 months. We conclude that anorectal surgical wounds heal in most HIV-infected patients and that the survival time after surgery of HIV-infected patients with anorectal disease justifies appropriate surgical treatment.


Assuntos
Canal Anal/cirurgia , Infecções por HIV/fisiopatologia , Reto/cirurgia , Cicatrização , Abscesso/cirurgia , Síndrome da Imunodeficiência Adquirida/fisiopatologia , Adulto , Canal Anal/fisiopatologia , Doenças do Ânus/cirurgia , Seguimentos , Infecções por HIV/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Retais/cirurgia , Reto/fisiopatologia , Estudos Retrospectivos
18.
Arch Surg ; 134(8): 889-97, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10443814

RESUMO

BACKGROUND: Mesangial enlargement (ME) is one of the hallmark lesions of diabetic nephropathy and plays a major role in diabetic renal failure. Conventional treatment of type 1 diabetes mellitus with insulin injections, diet, and medications has often failed to prevent development and progression of ME, presumably because of difficulty in achieving tight metabolic control. Although many pancreas transplantations have been done in patients with type 1 diabetes mellitus, there is insufficient information about their influence on ME or other diabetic lesions that are responsible for its morbidity and mortality. HYPOTHESIS: Whole pancreas transplantation will prevent diabetic ME throughout the life of the rat with alloxan-induced diabetes mellitus. DESIGN: Mesangial enlargement was studied for 28 months by a highly reproducible quantitative morphologic method in 55 nondiabetic control rats, 57 control rats with alloxan-induced diabetes mellitus, 97 diabetic rats that received a pancreaticoduodenal isograft shortly after the induction of diabetes mellitus, and 126 diabetic rats that received a duct-ligated pancreas isograft shortly after the induction of diabetes mellitus. Mesangial enlargement was determined by measuring the area occupied by camera lucida tracings of the mesangium using an electronic planimeter connected to a computer. RESULTS: Monthly metabolic studies showed that whole pancreas transplantation maintained very tight metabolic control of diabetes mellitus. Alloxan-induced diabetes mellitus produced progressive accumulation of mesangial matrix and progressive enlargement of all elements of the mesangium during the study. The 2 types of whole pancreas transplants provided lifelong protection against abnormal ME (P = .006). CONCLUSIONS: These results, combined with our previous finding of lifelong prevention of abnormal glomerular capillary basement membrane thickening, demonstrate that whole pancreas transplantation performed early in the course of alloxan-induced diabetes mellitus is capable of preventing diabetic kidney lesions. Moreover, these results suggest that whole pancreas transplants might be useful preventive therapy in patients with diabetes mellitus who undergo kidney transplantation for renal failure, in whom recurrence of nephropathy often develops in the transplanted kidney.


Assuntos
Diabetes Mellitus Experimental/cirurgia , Nefropatias Diabéticas/prevenção & controle , Mesângio Glomerular/patologia , Transplante de Pâncreas , Animais , Duodeno/transplante , Ratos , Ratos Endogâmicos Lew
19.
J Am Coll Surg ; 184(6): 557-70, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9179111

RESUMO

BACKGROUND: Intractable ascites, refractory to medical therapy, occurs in approximately 10 percent of patients with ascites from cirrhosis and is almost always fatal. Sinusoidal hypertension resulting from hepatic venous outflow obstruction plays a primary role in the pathogenesis of cirrhotic ascites and provides the rationale for decompression of the liver by side-to-side portacaval shunt in treatment of intractable ascites. This report presents the experimental basis for the use of side-to-side shunt and long-term results of a prospective study in 34 selected patients with intractable cirrhotic ascites. STUDY DESIGN: In the experimental studies, hepatic venous outflow obstruction and massive ascites were produced in dogs by ligation of the hepatic veins, and the effect of portacaval shunts on ascites, thoracic duct lymph flow, and aldosterone secretion were measured. In the clinical study, 34 carefully selected patients with cirrhosis (91 percent alcoholic) and truly intractable ascites (failure of medical therapy for 5 to 24 months) underwent side-to-side portacaval shunt. The effects on ascites, survival, metabolic abnormalities, and quality of life were studied prospectively during follow-up that was longer than 5 years in all but two patients. Quantitative Child's risk classes in percent of patients were A in 0, B in 68, and C in 32. RESULTS: In the experimental studies, side-to-side portacaval shunt permanently relieved severe ascites, reduced the 13-fold increase in thoracic duct lymph flow rate to almost normal, and abolished the aldosterone hypersecretory response to minimal hepatic venous outflow obstruction. End-to-side portacaval shunt was much less effective. In the clinical study, side-to-side portacaval shunt reduced mean portal vein-inferior vena cava pressure gradient from 282 mm saline to 4 mm and permanently relieved all patients of ascites without subsequent requirement of diuretic therapy. Two patients who died of hepatoma, and one who died of heart failure developed terminal ascites. Thirty-day mortality rate was 6 percent, and long-term survival rates at 5, 10, and 15 years were 75 percent, 74 percent, and 73 percent. In metabolic studies, side-to-side shunt produced marked diuresis and natriuresis and abolished hypersecretion of aldosterone. Quality of life was generally improved as a result of a low incidence of recurrent portal-systemic encephalopathy (6 percent), abstinence from alcohol in 91 percent, improvement in liver function in 81 percent, and improvement in Child's risk class. The portacaval anastomosis remained permanently patent in every patient. CONCLUSIONS: Side-to-side portacaval shunt is very effective treatment of intractable ascites from cirrhosis. Our results are attributable to careful selection of patients, an organized system of care, and a program of rigorous, lifelong follow-up that emphasizes abstinence from alcohol and dietary protein restriction.


Assuntos
Ascite/cirurgia , Cirrose Hepática Experimental/cirurgia , Cirrose Hepática/cirurgia , Derivação Portocava Cirúrgica/métodos , Adulto , Animais , Ascite/mortalidade , Ascite/fisiopatologia , Diurese , Cães , Feminino , Humanos , Cirrose Hepática/mortalidade , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Natriurese , Estudos Prospectivos , Qualidade de Vida , Taxa de Sobrevida , Resultado do Tratamento
20.
J Am Coll Surg ; 180(3): 257-72, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7874335

RESUMO

BACKGROUND: Emergency treatment of acute bleeding is of singular and paramount importance in the therapy of portal hypertension and esophagogastric varices. Accordingly, for more than three decades we have conducted prospective studies of emergency therapy, and particularly of emergency portacaval shunt (EPCS). STUDY DESIGN: Emergency portacaval shunt was performed upon 400 patients with cirrhosis of the liver and acutely bleeding esophagogastric varices according to three principles: operation within eight hours of initial contact; unselected patients, meaning that no patient with variceal bleeding caused by hepatic disease was excluded from EPCS, and prospective study, meaning that a well-defined protocol was consistently used and data were collected on-line. Patients were divided into an early group of 180 treated from 1963 to 1978 and a recent group of 220 treated from 1978 to July, 1990, with similar characteristics, but strikingly different outcome. Follow-up rates at one, five, and ten years were 100, 98, and 97 percent, respectively; 96 percent of patients underwent EPCS five or more years ago. Proof of acute variceal bleeding and of cirrhosis of the liver (alcoholic in 95 percent) was obtained in every patient. Child's risk classes determined quantitatively were A in 11 percent of the patients, B in 65 percent, and C in 24 percent. All patients had a direct portacaval shunt, side-to-side in 85 percent, which reduced the mean portal vein to inferior vena cava pressure gradient from 271 to 21 mm saline solution. RESULTS: All but four patients (99 percent) had immediate and permanent control of variceal bleeding. Thrombosis of the shunt occurred in only two patients (0.5 percent). Survival rates at 30 days, five years, ten years, and 15 years in the early group were 58, 40, 30, and 30 percent, respectively, while in the recent group they were 85, 78, 71, and 57 percent, respectively (p < 0.0001). Other striking gains in the recent group were abstention from alcohol, improvement in liver function and improvement in Child's class, all in 70 percent of patients. Recurrent portal-systemic encephalopathy occurred in 9 percent of the early group and 8 percent of the recent group. CONCLUSIONS: Emergency portacaval shunt substantially improved survival and quality of life of patients with cirrhosis of the liver and bleeding varices. Our results are attributable to rapid and simplified diagnosis, prompt operation, an organized system of care, and rigorous, lifelong follow-up evaluation that emphasized abstinence from alcohol and dietary protein control. Transplantation of the liver is infrequently required in patients whose bleeding is permanently controlled.


Assuntos
Varizes Esofágicas e Gástricas/cirurgia , Hemorragia Gastrointestinal/cirurgia , Cirrose Hepática Alcoólica/complicações , Derivação Portocava Cirúrgica , Adulto , Idoso , Pressão Sanguínea/fisiologia , Emergências , Varizes Esofágicas e Gástricas/prevenção & controle , Feminino , Seguimentos , Hemorragia Gastrointestinal/prevenção & controle , Encefalopatia Hepática/etiologia , Humanos , Hipertensão Portal/complicações , Hipertensão Portal/fisiopatologia , Cirrose Hepática Alcoólica/fisiopatologia , Masculino , Pessoa de Meia-Idade , Derivação Portocava Cirúrgica/efeitos adversos , Derivação Portocava Cirúrgica/métodos , Veia Porta/fisiopatologia , Estudos Prospectivos , Qualidade de Vida , Recidiva , Taxa de Sobrevida , Temperança , Resultado do Tratamento , Veia Cava Inferior/fisiopatologia
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