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2.
Ann Surg ; 250(5): 825-30, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19916210

RESUMO

OBJECTIVE: To summarize the current world position on laparoscopic liver surgery. SUMMARY BACKGROUND DATA: Multiple series have reported on the safety and efficacy of laparoscopic liver surgery. Small and medium sized procedures have become commonplace in many centers, while major laparoscopic liver resections have been performed with efficacy and safety equaling open surgery in highly specialized centers. Although the field has begun to expand rapidly, no consensus meeting has been convened to discuss the evolving field of laparoscopic liver surgery. METHODS: On November 7 to 8, 2008, 45 experts in hepatobiliary surgery were invited to participate in a consensus conference convened in Louisville, KY, US. In addition, over 300 attendees were present from 5 continents. The conference was divided into sessions, with 2 moderators assigned to each, so as to stimulate discussion and highlight controversies. The format of the meeting varied from formal presentation of experiential data to expert opinion debates. Written and video records of the presentations were produced. Specific areas of discussion included indications for surgery, patient selection, surgical techniques, complications, patient safety, and surgeon training. RESULTS: The consensus conference used the terms pure laparoscopy, hand-assisted laparoscopy, and the hybrid technique to define laparoscopic liver procedures. Currently acceptable indications for laparoscopic liver resection are patients with solitary lesions, 5 cm or less, located in liver segments 2 to 6. The laparoscopic approach to left lateral sectionectomy should be considered standard practice. Although all types of liver resection can be performed laparoscopically, major liver resections (eg, right or left hepatectomies) should be reserved for experienced surgeons facile with more advanced laparoscopic hepatic resections. Conversion should be performed for difficult resections requiring extended operating times, and for patient safety, and should be considered prudent surgical practice rather than failure. In emergent situations, efforts should be made to control bleeding before converting to a formal open approach. Utilization of a hand assist or hybrid technique may be faster, safer, and more efficacious. Indications for surgery for benign hepatic lesions should not be widened simply because the surgery can be done laparoscopically. Although data presented on colorectal metastases did not reveal an adverse effect of the laparoscopic approach on oncological outcomes in terms of margins or survival, adequacy of margins and ability to detect occult lesions are concerns. The pure laparoscopic technique of left lateral sectionectomy was used for adult to child donation while the hybrid approach has been the only one reported to date in the case of adult to adult right lobe donation. Laparoscopic liver surgery has not been tested by controlled trials for efficacy or safety. A prospective randomized trial appears to be logistically prohibitive; however, an international registry should be initiated to document the role and safety of laparoscopic liver resection. CONCLUSIONS: Laparoscopic liver surgery is a safe and effective approach to the management of surgical liver disease in the hands of trained surgeons with experience in hepatobiliary and laparoscopic surgery. National and international societies, as well as governing boards, should become involved in the goal of establishing training standards and credentialing, to ensure consistent standards and clinical outcomes.


Assuntos
Hepatectomia/métodos , Laparoscopia , Hepatopatias/cirurgia , Humanos , Laparoscopia/métodos , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Doadores Vivos , Procedimentos Cirúrgicos Minimamente Invasivos , Seleção de Pacientes , Coleta de Tecidos e Órgãos
3.
Surgery ; 146(3): 462-8, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19715802

RESUMO

BACKGROUND: An academic surgeon's workweek is divided among patient care, administrative duties, education, and research. The time available for research activities may change as a surgeon's career evolves. We sought to determine involvement of academic surgeons in research and to assess how this research endeavor was affected by demographic and workplace characteristics. METHODS: We constructed a survey to explore the following 4 domains: demographics, time allotment, research activities, and effects of stressors. We distributed the survey to members of the Society of University Surgeons. In addition to performing descriptive statistics, we defined an active researcher as someone with a funding source who devoted 15% or more work hours to research. Using this definition, we performed statistical analyses to assess the significance of independent variables on research. Stress factors were evaluated on a Likert scale with responses ranging from 1 (not at all) to 5 (extremely). RESULTS: We received 314 completed surveys (response rate 23%). Of the respondents, 274 (87%) stated that they were involved in some kind of research activity; however, only 143 (46%) were active researchers. Using univariate logistic regression analysis, younger respondents and surgeons who practiced for more than 10 years were more likely to be active researchers (odds ratio [OR]: 1.93, confidence interval [CI]: 1.51-2.46 and OR: 2.06, CI: 1.64-2.59, respectively). Males were less likely than females to be active researchers (OR: 0.32, CI: 016-0.67); however, by multivariate analysis, we found that the "years in practice" of an active researcher was the most significant predictor of research activity, whereas age and sex were not. In regard to stress, most respondents reported scores of 1-3 for all 7 stressors, which is consistent with minimal to moderate stress. CONCLUSION: Academic surgeons are involved actively in research; however, this involvement decreases as other professional responsibilities increase. To optimize the surgical research environment, departments should invest time and resources in young investigators to prevent them from decreasing their research activities.


Assuntos
Cirurgia Geral , Centros Médicos Acadêmicos , Adulto , Idoso , Coleta de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa , Estresse Psicológico , Trabalho
4.
Liver Transpl ; 15(8): 915-23, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19642135

RESUMO

Liver allografts are spontaneously accepted in the liver transplantation mouse model; however, the basis for this tolerance and the conditions that abrogate spontaneous tolerance to liver allografts are incompletely understood. We examined the role of CpG oligodeoxynucleotide (ODN) in triggering the liver inflammatory reaction and allograft rejection. Bioluminescence imaging quantified the activation of nuclear transcriptional factor kappaB (NF-kappaB) at different time points post-transplantation. Intrahepatic lymphocyte subsets were analyzed by immunofluorescence assay and flow cytometry. The results showed that liver allografts survived for more than 100 days without a requirement for any immunosuppressive therapy. Donor-matched cardiac allografts were permanently accepted, whereas third-party cardiac grafts were rejected with delayed kinetics; this confirmed donor-specific tolerance. NF-kappaB activation in the liver allografts was transiently increased on day 1 and diminished by day 4; in comparison, it was elevated up to 10 days post-transplantation in the cardiac allografts. When CpG ODN was administered at a high dose (50 microg per mouse x 1) to the recipients on day 7 post-transplantation, it induced an acute liver inflammatory reaction with elevated NF-kappaB activation in both allogeneic and syngeneic liver grafts. Multiple doses of CpG ODN (10 microg per mouse x 3) elicited acute rejection of the liver allografts with significant T cell infiltration in the liver allografts, reduced T regulatory cells, and enhanced interferon gamma-producing cells in the intrahepatic infiltrating lymphocytes. These data demonstrate that CpG ODN initiates an inflammatory reaction and abrogates spontaneous tolerance in the liver transplantation mouse model. Liver Transpl 15:915-923, 2009. (c) 2009 AASLD.


Assuntos
Ilhas de CpG , Transplante de Fígado/imunologia , Fígado/patologia , Oligonucleotídeos/genética , Animais , Citometria de Fluxo/métodos , Tolerância Imunológica , Inflamação , Cinética , Transplante de Fígado/métodos , Linfócitos/citologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência/métodos , NF-kappa B/metabolismo , Linfócitos T/imunologia
5.
Transplantation ; 87(4): 507-16, 2009 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-19307786

RESUMO

BACKGROUND: Protein kinase C-theta (PKCtheta) mediates critical T-cell receptor signals required for T-cell activation. We have recently shown that PKCtheta knockout (PKCtheta, H-2b) T cells, when transferred into T/B cell-deficient mice, failed to reject fully allogeneic (H-2d) cardiac grafts and that transgenic expression of antiapoptotic Bcl-xL gene in PKCtheta T cells restored allograft rejection. METHODS: We used PKCtheta mice as recipients of cardiac allografts, compared with wild-type (WT) cardiac allograft transplantation. Anti-CD154 monoclonal antibody (MR1) and human CTLA4Ig were sued to induce donor-specific tolerance. T-cell proliferation, T-cell subsests, nuclear factor kappa B (NF-kappaB) activation, and Bax and Bcl-xL were analyzed. RESULTS: Although suboptimal anti-CD154 monoclonal antibody or human CTLA4Ig failed to delay cardiac allograft rejection in WT mice, the same therapy induced long-term survival of cardiac allografts in PKCtheta mice. Donor-type second cardiac allografts (H-2d) were accepted, and third-party heart allografts (H-2k) were rejected by tolerant PKCtheta mice. However, tolerance state could not be effectively transferred with T cells from tolerance PKCtheta mice. Compared with WT mice, reduced NF-kappaB activation, T-cell proliferation, and T-cell infiltration in PKCtheta spleens were observed. PKCtheta mice reveal reduced CD4/CD25/FoxP3, Th1/Th17 subsets, and mouse MHC class II (IE)-reactive CD4Vbeta11 T cells. Apoptotic molecule, Bax, was increased and antiapoptotic molecule, Bcl-xL, was reduced in PKCtheta spleen cells. CONCLUSION: We concluded that PKCtheta mice have a defected alloimmune response and are susceptible to tolerance induction, which is associated with a clonal deletion of T-cell subsets.


Assuntos
Transplante de Coração/imunologia , Isoenzimas/deficiência , Proteína Quinase C/deficiência , Animais , Anticorpos Monoclonais/uso terapêutico , Antígenos CD/imunologia , Ligante de CD40/imunologia , Antígeno CTLA-4 , Humanos , Tolerância Imunológica , Ativação Linfocitária , Teste de Cultura Mista de Linfócitos , Linfócitos/citologia , Linfócitos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Quinase C-theta , Subpopulações de Linfócitos T/imunologia , Linfócitos T/imunologia , Transplante Homólogo
6.
J Surg Res ; 154(2): 226-33, 2009 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-19059606

RESUMO

BACKGROUND: Liver regeneration following partial hepatectomy requires the orchestration of highly regulated molecular pathways; a change in the abundance or activity of a specific gene product has the potential to adversely affect this process. The nuclear factor of activated T-cells (NFAT) transcription factors represent a family of gene transcription signaling intermediates that translate receptor-dependent signaling events into specific transcriptional responses using the Ras/Raf pathway. MATERIALS AND METHODS: Eight-week old NFAT4 knockout (KO) mice and their wild type counterparts (Balb-c) underwent two-thirds partial hepatectomy. The animals were sacrificed and their livers were harvested at specific time points during regeneration. Recovery of liver mass was measured for each time point. PCR analysis was used to analyze expression levels of the immediate early genes c-fos, c-jun and c-myc as well as downstream effectors of NFAT4 including FGF-18 and BMP-4. RESULTS: Hepatocyte proliferation and thus liver regeneration following hepatectomy was suppressed in NFAT4 knockout (KO) mice. Statistical significance was reached at 1 h, 7 d, and 10 d (P < 0.05) with a 22% median reduction in regeneration of liver mass in the NFAT4 KO mice by 10 d, at which time liver regeneration should be complete in mice. The immediate early gene c-fos was elevated in NFAT4 KO mice during early regeneration with a median value at 1 h and 1 d of 1.60E-08 and 1.09E-08 versus 6.10E-09 and 1.55E-09 in the Balb-c mice. C-jun, in contrast, was elevated during late regeneration in the NFAT4 KO mice (3.40E-09 and 5.67E-09 at 7 and 10 d, respectively) in comparison with the Balb-c mice (7.76E-10 and 1.24E-09, respectively.). NFAT2 was also up-regulated in the NFAT4 KO mice; however, no changes were detected in its downstream effectors, CCR1 and CCL3. CONCLUSIONS: We demonstrated that NFAT4 deficiency impairs hepatic regeneration in a murine model proving that NFAT4 plays an important yet unclear role in liver regeneration; its absence may be compensated by c-fos, c-jun, and NFAT2 expression changes.


Assuntos
Hepatectomia , Regeneração Hepática/fisiologia , Fígado/fisiologia , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/metabolismo , Animais , Apoptose/fisiologia , Proteína Morfogenética Óssea 4/genética , Divisão Celular/fisiologia , Fatores de Crescimento de Fibroblastos/genética , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fígado/citologia , Fígado/cirurgia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Transdução de Sinais/fisiologia , Regulação para Cima/fisiologia
7.
HPB (Oxford) ; 10(5): 321-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18982146

RESUMO

INTRODUCTION: Several methods for hepatic parenchymal division exist. The primary aim was to assess differences in postoperative bile leaks, operative blood loss, and margin status between three transection methods: crush/clamp (CC), stapler (SP), or dissecting sealer (DS). METHODS: A single institution, retrospective cohort study was performed on data collected over a three-year period in patients undergoing elective liver resection using the CC, SP, or DS. Patients were excluded if multiple methods of transection were used or for intraoperative death. The association of bile leak with transection type was assessed. A logistic regression model was tested to assess if blood loss was associated with the covariates of transection method, use of portal inflow occlusion, extent of liver resection, and other concurrent major operations. RESULTS: Analyses included 141 patients. The stapler method was quicker than the other methods (p=0.01). The risk of postoperative bile leak was no different between CC, SP, and DS transection methods (p=0.23). There was no difference in mean blood loss or transfusions; however, hepatectomies performed with DS were associated with an increased risk of blood loss > or = 1000 mL compared to CC (p=0.04). There were no differences in mean surgical margin between the three methods. CONCLUSION: The risk of bile leaks was not different between the three methods. While mean blood loss was similar, hepatectomy performed with the DS was associated with an increased risk of having operative blood loss > or = 1000 mL compared to CC. Margins were equal by all methods. The stapler method was quicker.

8.
Transplantation ; 86(2): 238-44, 2008 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-18645485

RESUMO

BACKGROUND: Liver transplantation is a costly procedure and its cost is likely driven by both donor and recipient factors. Recently, the recipient model for end-stage liver disease (MELD) score has been correlated with increased posttransplant cost; however, other factors have not been identified. We sought to identify if other donor and recipient factors are associated with increased cost. METHODS: One hundred sixty-six liver transplants performed at our center from January 2004 through February 2006 were included in the estimation sample, and the subsequent 75 transplants were used as a validation cohort. To determine whether donor factors influenced cost, two latent class linear regression models were created from the estimation sample: one considering only recipient variables (model A) and a second incorporating both donor and recipient factors (model B). The resultant models were then validated in the second group of patients and compared with the best single-segment linear regression models. RESULTS: Model A predictors include pretransplant intensive care unit (ICU) stay, age x body mass index, and calculated MELD. In model B, significant predictors are calculated MELD, age, age x pretransplant ICU stay, and donor age more than 40 as significant variables. In validation, only model A remained predictive of cost. CONCLUSIONS: Although marginal donor factors are recognized to influence clinical outcome, they did not factor significantly in cost modeling. In addition to MELD, the recipient factors of pretransplant ICU stay, age, and body mass index are pretransplant variables correlated mostly with posttransplant cost across broad populations.


Assuntos
Falência Hepática/terapia , Transplante de Fígado/economia , Idoso , Estudos de Coortes , Feminino , Custos de Cuidados de Saúde , Humanos , Transplante de Fígado/métodos , Masculino , Pessoa de Meia-Idade , Modelos Econômicos , Avaliação de Resultados em Cuidados de Saúde , Análise de Regressão , Doadores de Tecidos , Obtenção de Tecidos e Órgãos/economia , Obtenção de Tecidos e Órgãos/métodos , Resultado do Tratamento
9.
J Am Coll Surg ; 206(5): 857-68; discussion 868-9, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18471711

RESUMO

BACKGROUND: The purpose of this study was to develop a prognostic system applicable to patients with hepatic metastasis from colorectal cancer in whom extrahepatic disease was excluded by preoperative PET with [(18)F]fluoro-2-deoxy-D-glucose (FDG-PET). Data from two institutions were analyzed separately and together to improve general applicability of results. STUDY DESIGN: Data were analyzed for 285 consecutive patients undergoing liver resection for colorectal metastases from 1995 to 2005 at 2 institutions routinely using preoperative FDG-PET with. Fifteen clinicopathologic variables of the primary and secondary tumors were examined to identify factors predictive of survival. RESULTS: Outcomes were correlated with poorly differentiated tumor grade in both data sets. Because patients with poorly differentiated tumors comprised a small proportion (16%) of the population, patients with well-differentiated or moderately differentiated tumors were analyzed independently. In this subgroup, positive lymph node status in the primary colorectal tumor resection specimen was the only characteristic that predicted survival of patients in both institutions. Consequently, patients were sorted into three prognostic categories: poor tumor differentiation; well-differentiated or moderately differentiated tumors and node positive; and well-differentiated or moderately differentiated tumors and node negative. These groups had significantly different overall survival on Kaplan-Meier analysis (p=0.0014). CONCLUSIONS: In patients with colorectal liver metastases staged with FDG-PET with overall survival can be predicted directly from data in the pathology report of the colorectal primary tumor. This study also indicates the need for new molecular tumor markers of prognosis to complement clinicopathologic markers if the goal of prediction of outcomes in individual patients is to be reached.


Assuntos
Neoplasias Colorretais/cirurgia , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Fluordesoxiglucose F18 , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons , Prognóstico , Compostos Radiofarmacêuticos , Viloxazina
10.
J Surg Res ; 141(2): 234-40, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17574598

RESUMO

BACKGROUND: Purinergic (P2Y) receptors play an important role in intracellular Ca(2+) regulation in hepatocytes. Prevention of mitochondrial Ca(2+) (mCa(2+)) overload during ischemic conditions prevents cellular cell death during the early reperfusion period. P2Y antagonists are cytoprotective in other settings. We studied the effect of P2Y receptor antagonism on mitochondrial associated cell death during the period of cold storage. METHODS: HepG2 cells were stored in UW with or without 300 muM reactive blue 2 (RB2) or 10 muM ruthenium red (RR) under either normoxic-hypothermic or hypoxic-hypothermic conditions. Cytoplasmic cytochrome c levels were studied by transfection of cytochrome c-GFP. Immunofluorescence determined the intracellular, spatio-temporal distribution of Bax, and terminal deoxynucleotidyl transferase mediated dUTP nick end labeling staining was used to evaluate cell death. Intracellular compartmental ATP levels were assayed by transfecting with luciferase vectors specific for cytoplasm (PcDNA3-luciferase-LL/V) and mitochondria (PcDNA3-COX8-luciferase). RESULTS: Bax translocation to the mitochondria occurred immediately following cold storage and was followed by cytochrome c-GFP redistribution to the cytosol during rewarming. RB2 treatment significantly attenuated Bax translocation, cytochrome c-GFP redistribution, and cell death following both storage conditions. Both RR and RB2 provided cytoprotection despite ongoing cytoplasmic ATP consumption during cold ischemia. CONCLUSION: These data indicate that the cytoprotective effects of mCa(2+) uptake inhibition and P2Y receptor antagonism are independent of cytoplasmic ATP levels during cold ischemia.


Assuntos
Trifosfato de Adenosina/análise , Apoptose/efeitos dos fármacos , Antagonistas do Receptor Purinérgico P2 , Preservação de Tecido/métodos , Linhagem Celular Tumoral , Temperatura Baixa , Citocromos c/metabolismo , Citosol/química , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Humanos , Mitocôndrias/química , Transporte Proteico , Rutênio Vermelho/farmacologia , Triazinas/farmacologia , Proteína X Associada a bcl-2/metabolismo
11.
Liver Transpl ; 13(5): 647-50, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17377915

RESUMO

Thymoglobulin (Genzyme, Cambridge, MA) is an antithymocyte globulin preparation used for induction immunosuppression therapy in solid organ transplantation. It is being utilized with increasing frequency in orthotopic liver transplantation (OLT) in an effort to minimize or delay the use of calcineurin inhibitors due to their inherent nephrotoxicity. Experience with thymoglobulin in OLT remains limited. We report a case of serum sickness in a patient who received thymoglobulin following OLT. The patient experienced intermittent fevers, polyarthralgia, and acute renal failure 9 days after completion of thymoglobulin administration. The patient's symptoms resolved rapidly and completely with a course of intravenous steroids. We review a set of diagnostic criteria for serum sickness and emphasize the importance of early recognition of the process. Early treatment of serum sickness with steroids or plasmapheresis is highly effective and can reduce unnecessary morbidity from this unusual sequela of induction immunosuppression with antithymocyte globulin.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Transplante de Fígado , Doença do Soro/etiologia , Injúria Renal Aguda/etiologia , Animais , Anticorpos Monoclonais/uso terapêutico , Soro Antilinfocitário , Feminino , Glucocorticoides/administração & dosagem , Glucocorticoides/uso terapêutico , Humanos , Injeções Intravenosas , Metilprednisolona/administração & dosagem , Metilprednisolona/uso terapêutico , Pessoa de Meia-Idade , Coelhos , Resultado do Tratamento
12.
Cancer Res ; 67(6): 2720-8, 2007 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-17363593

RESUMO

Surgical resection remains the best treatment for colorectal metastases isolated to the liver; however, 5-year survival rates following liver resection are only 40% to 50%, with liver recurrence being a significant reason for treatment failure. The ischemia-reperfusion (I/R) injury incurred during liver surgery can lead to cellular dysfunction and elevations in proinflammatory cytokines and matrix metalloproteinases (MMP). In rodents, I/R injury to the liver has been shown to accelerate the outgrowth of implanted tumors. The mechanism for increased tumor growth in the setting of liver I/R injury is unknown. To investigate the effect of I/R on tumor growth, an experimental model was used whereby small hepatic metastases form after 28 days. Mice subjected to 30 min of 70% liver ischemia at the time of tumor inoculation had significantly larger tumor number and volume, and had elevated MMP9 serum and liver tissue MMP9 as evidenced by zymography and quantitative real-time PCR. Mice treated with doxycycline, a broad-spectrum MMP inhibitor, had reduced MMP9 levels and significantly smaller tumor number and volume in the liver. MMP9-null mice were used to determine if the effects of doxycycline were due to the absence of stromal-derived MMP9. The MMP9-null mice, with or without doxycycline treatment, had reduced tumor number and volume that was equivalent to wild-type mice treated with doxycycline. These findings indicate that hepatic I/R-induced elevations in MMP9 contribute to the growth of metastatic colorectal carcinoma in the liver and that postresection MMP9 inhibition may be clinically beneficial in preventing recurrence following hepatic surgery.


Assuntos
Adenocarcinoma/secundário , Neoplasias Colorretais/patologia , Isquemia/enzimologia , Neoplasias Hepáticas Experimentais/secundário , Fígado/irrigação sanguínea , Metaloproteinase 9 da Matriz/biossíntese , Traumatismo por Reperfusão/enzimologia , Adenocarcinoma/enzimologia , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/enzimologia , Doxiciclina/farmacologia , Indução Enzimática , Feminino , Isquemia/patologia , Fígado/enzimologia , Neoplasias Hepáticas Experimentais/enzimologia , Neoplasias Hepáticas Experimentais/patologia , Neoplasias Hepáticas Experimentais/cirurgia , Masculino , Metaloproteinase 9 da Matriz/sangue , Metaloproteinase 9 da Matriz/genética , Inibidores de Metaloproteinases de Matriz , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reperfusão/efeitos adversos , Reperfusão/métodos , Traumatismo por Reperfusão/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima
14.
Liver Transpl ; 13(2): 234-8, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17256781

RESUMO

Biliary complications following orthotopic liver transplantation have been reported in 10% to 30% of patients. Most surgeons perform an end-to-end choledochocholedochostomy with interrupted sutures for biliary reconstruction. The goal of this study was to compare biliary complications between interrupted suture (IS) and continuous suture (CS) techniques during liver transplantation in which an end-to-end choledochocholedochostomy over an internal biliary stent was performed. A retrospective cohort study of 100 consecutive liver transplants occurring between December 2003 and July 2005 was conducted. An end-to-end choledochocholedochostomy over an internal biliary stent was performed during liver transplantation. Data were analyzed using Kaplan-Meier methods, t tests, and chi-square tests of proportions. IS and CS techniques were used in 59 and 41 patients, respectively, for biliary reconstruction during liver transplantation. Mean follow-up time for the CS group was 17 +/- 8 months and 15 +/- 7 months for the IS group (P = .21). The overall biliary complication rate was 15%. There was no difference in the proportion of leaks (CS = 7.3%, IS = 8.5%; P = .83) or strictures (CS = 9.8%, IS = 5.1%; P = .37) between groups. Kaplan-Meier event rates show no difference in leaks (P = .79), strictures (P = .41), graft survival (P = .52), and patient survival (P = .32) by anastomosis type. In conclusion, there was no difference in biliary complications, graft survival, or patient survival between the 2 groups. CS and IS techniques for biliary reconstruction during liver transplantation yield comparable outcomes.


Assuntos
Doenças do Ducto Colédoco/diagnóstico , Ducto Colédoco/cirurgia , Transplante de Fígado , Complicações Pós-Operatórias/diagnóstico , Técnicas de Sutura , Adulto , Idoso , Anastomose Cirúrgica , Feminino , Rejeição de Enxerto/diagnóstico , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
16.
J Cell Biochem ; 99(4): 1165-74, 2006 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16795051

RESUMO

Ischemia-reperfusion injury remains a major clinical problem in liver transplantation. One contributing factor is mitochondrial calcium (mCa(2+)) overload, which triggers apoptosis; calcium also regulates mitochondrial respiration and adenosine 5'-triphosphate (ATP) production. Recently, we reported the presence of purinergic P2Y(1)- and P2Y(2)-like receptor proteins in mitochondrial membranes. Herein, we present an evaluation of the functional characteristics of these receptors. In experiments with isolated mitochondria, specific P2Y(1) and P2Y(2) receptors ligands: 2-methylthio-adenosine 5'-diphosphate (2meSADP) and uridine 5'-triphosphate (UTP), respectively, were used, and mitochondrial calcium uptake was measured. 2meSADP and UTP had a maximum effect at concentrations in the range of the known P2Y(1) and P2Y(2) receptors. The P2Y inhibitor phosphate-6-azophenyl-2',4'-disulfonate (PPADS) blocked the effects of both ligands. The phospholipase C (PLC) antagonist U73122 inhibited the effect of both ligands while its inactive analog U73343 had no effect. These data strongly support the hypothesis that mitochondrial Ca(2+) uptake is regulated in part by adenine nucleotides via a P2Y-like receptor mechanism that involves mitochondrial PLC activation.


Assuntos
Cálcio/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Receptores Purinérgicos P2/metabolismo , Difosfato de Adenosina/análogos & derivados , Difosfato de Adenosina/farmacologia , Adenilil Imidodifosfato/farmacologia , Animais , Sinalização do Cálcio/efeitos dos fármacos , Transporte de Íons/efeitos dos fármacos , Ligantes , Masculino , Mitocôndrias/efeitos dos fármacos , Modelos Biológicos , Agonistas do Receptor Purinérgico P2 , Ratos , Ratos Sprague-Dawley , Receptores Purinérgicos P2Y1 , Receptores Purinérgicos P2Y2 , Fosfolipases Tipo C/antagonistas & inibidores
17.
J Gastrointest Surg ; 10(5): 761-80, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16713550

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common tumors globally, with varying prevalence based on endemic risk factors. In high-risk populations, including those with hepatitis B or C or with cirrhosis, serum alpha-fetoprotein (AFP) and screening ultrasound have improved detection of resectable HCC. Treatment options, including surgical resection, for patients with HCC must be selected based on the number and size of hepatic tumors, underlying hepatic function, patient condition, and available resources. An approach, which has been summarized shows the corresponding treatment choices under given clinical circumstances. For cirrhotic patients with less than three tumor nodules of a size less than 3 cm or a solitary HCC less than 5 cm, liver transplantation offers long-term survival similar to that observed in patients transplanted for nonmalignant disease. Ablative treatment using either chemical or thermal techniques provides locally effective tumor destruction. Transcatheter arterial chemoembolization (TACE) is commonly used for palliation of unresectable tumors as well as an adjunct to surgical resection, treatment of tumors before transplant, and in conjunction with other ablative therapies in a multimodality approach. Regional approaches to chemotherapy have produced more encouraging results than systemic chemotherapy, although both remain ineffective for long-term tumor control. Several newer treatment modalities are under investigation, including gene therapy, tagged antibodies, isolated perfusion, and novel radiotherapy techniques.


Assuntos
Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Ablação por Cateter , Quimioembolização Terapêutica , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Estadiamento de Neoplasias , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
Transplantation ; 81(4): 567-72, 2006 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-16495805

RESUMO

BACKGROUND: Graft failure due to cold ischemia (CI) injury remains a significant problem during liver transplantation. During CI, the consumption of ATP and the increase in cellular Ca concentration may result in mitochondrial Ca (mCa) overload through the mCa uniporter, which can ultimately lead to apoptosis and graft nonfunction. We recently identified phospholipase C-dl (PLC-dl) as a novel regulator of mCa uptake in the liver, and now extend those studies to examine the role of mitochondrial PLC in liver CI injury. METHODS: Rat livers were perfused with University of Wisconsin (UW) solution. Half was homogenized immediately; the other half was cold-stored for 24 hr in UW. Mitochondria were extracted by differential centrifugation and incubated in buffer containing ATP and 0.1 or 0.2 microM Ca. The selective PLC inhibitor, U-73122, was added to determine the effects of PLC inhibition on mCa uptake following CI. Western blots and densitometry quantified mitochondrial PLC expression. Mito Tracker Red fluorescence microscopy was used to verify mitochondrial transmembrane potential. RESULTS: Twenty-four hour CI caused a significant increase in mCa uptake (P<0.001), and increasing extramitochondrial Ca potentiated this effect. The PLC inhibitor, U-73122, decreased mCa uptake in nonischemic mitochondria (P<0.001), and had a greater effect on CI mitochondria (P<0.001). Mitochondrial PLC-dl expression increased 175+/-75% following CI (P<0.05). CONCLUSIONS: These data demonstrate that PLC-dl is essential for mCa uptake following CI, and that the PLC pathway may be sensitized by CI. The CI-induced increase in mitochondrial PLC-delta1 expression represents a novel mechanism whereby mCa uptake can increase independently of cytosolic conditions.


Assuntos
Cálcio/metabolismo , Isquemia/fisiopatologia , Fígado/irrigação sanguínea , Mitocôndrias Hepáticas/fisiologia , Fosfolipases Tipo C/antagonistas & inibidores , Trifosfato de Adenosina/farmacologia , Animais , Transporte Biológico/efeitos dos fármacos , Cálcio/farmacologia , Masculino , Mitocôndrias Hepáticas/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
19.
Transplantation ; 81(1): 21-5, 2006 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-16421472

RESUMO

BACKGROUND: Graft-versus-host disease (GVHD) is a rare complication following liver transplantation and carries a poor prognosis with mortality approaching 90-95%. Diagnosis of GVHD is often delayed due to early symptoms mimicking more common, entities such as drug reactions and viral syndromes. To date, definitive diagnosis has been difficult and has relied on a constellation of clinical and histopathologic variables. We present the use of short tandem repeat DNA "fingerprinting" technology as a method of early, definitive diagnosis of GVHD in patients after liver transplantation. METHODS: A patient status-postorthotopic cadaveric-liver transplant, with an uncomplicated immediate posttransplant course, presented 4 weeks after transplant with fever, diarrhea, and maculopapular rash on her palms, soles, and back. The patient's condition worsened despite empiric treatment for an infectious etiology. Skin and rectal biopsies were suspicious for GVHD. RESULTS: DNA was isolated from the skin and rectal biopsies as well as from a donor lymph node. PCR amplification was done for nine highly polymorphic short tandem repeats for each specimen and a unique DNA "fingerprint" was obtained from each. DNA from skin and rectum demonstrated mixed chimerism with both donor and recipient alleles detected. Thorough analysis confirmed GVHD. CONCLUSION: Short tandem repeats for DNA fingerprinting represents an efficient and reproducible method for the definitive diagnosis of GVHD after liver transplantation. Rapid detection of GVHD using this technology, coupled with early initiation of therapy, may lead to improved survival for patients with GVHD after solid organ transplant.


Assuntos
Impressões Digitais de DNA/métodos , Doença Enxerto-Hospedeiro/diagnóstico , Doença Enxerto-Hospedeiro/genética , Transplante de Fígado , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Fatores de Tempo
20.
J Virol ; 80(3): 1077-86, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16414985

RESUMO

Reovirus infection activates NF-kappaB, which leads to programmed cell death in cultured cells and in the murine central nervous system. However, little is known about how NF-kappaB elicits this cellular response. To identify host genes activated by NF-kappaB following reovirus infection, we used HeLa cells engineered to express a degradation-resistant mutant of IkappaBalpha (mIkappaBalpha) under the control of an inducible promoter. Induction of mIkappaBalpha inhibited the activation of NF-kappaB and blocked the expression of NF-kappaB-responsive genes. RNA extracted from infected and uninfected cells was used in high-density oligonucleotide microarrays to examine the expression of constitutively activated genes and reovirus-stimulated genes in the presence and absence of an intact NF-kappaB signaling axis. Comparison of the microarray profiles revealed that the expression of 176 genes was significantly altered in the presence of mIkappaBalpha. Of these genes, 64 were constitutive and not regulated by reovirus, and 112 were induced in response to reovirus infection. NF-kappaB-regulated genes could be grouped into four distinct gene clusters that were temporally regulated. Gene ontology analysis identified biological processes that were significantly overrepresented in the reovirus-induced genes under NF-kappaB control. These processes include the antiviral innate immune response, cell proliferation, response to DNA damage, and taxis. Comparison with previously identified NF-kappaB-dependent gene networks induced by other stimuli, including respiratory syncytial virus, Epstein-Barr virus, tumor necrosis factor alpha, and heart disease, revealed a number of common components, including CCL5/RANTES, CXCL1/GRO-alpha, TNFAIP3/A20, and interleukin-6. Together, these results suggest a genetic program for reovirus-induced apoptosis involving NF-kappaB-directed expression of cellular genes that activate death signaling pathways in infected cells.


Assuntos
Regulação da Expressão Gênica , Orthoreovirus Mamífero 3/patogenicidade , NF-kappa B/metabolismo , Animais , Perfilação da Expressão Gênica , Células HeLa , Humanos , Proteínas I-kappa B/genética , Proteínas I-kappa B/metabolismo , Células L , Camundongos , Mutação , Inibidor de NF-kappaB alfa , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Infecções por Reoviridae/genética , Infecções por Reoviridae/imunologia , Infecções por Reoviridae/metabolismo
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