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1.
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
2.
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
3.
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
4.
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
5.
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
6.
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
7.
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
8.
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
9.
Arch Surg ; 140(3): 273-7, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15781792

RESUMO

HYPOTHESIS: Donor, technical, and recipient risk factors cumulatively impact survival and health-related quality of life after liver transplantation. DESIGN: Retrospective study. SETTING: Tertiary care center. PATIENTS: A total of 483 adults undergoing primary orthotopic liver transplantation between January 1, 1991, and July 31, 2003. MAIN OUTCOME MEASURES: Graft and patient survival, Karnofsky functional performance scores, Medical Outcomes Study Short Form 36 Health Survey scores, and Psychosocial Adjustment to Illness Scale scores as influenced by potential risk factors including donor age, weight, warm ischemia time, cold ischemia time (CIT), sex, United Network for Organ Sharing (UNOS) status (1 or 2A vs 2B or 3), recipient age and disease, bilirubin level, and creatinine level. RESULTS: Five-year graft survival was 72% for recipients of donors younger than 60 years and 35% for recipients of donors 60 years and older (P<.001). A CIT of 12 hours or more was associated with shorter 5-year graft survival (71% vs 58%; P = .004). Five-year graft survival for UNOS status 2B or 3 was 71% vs 60% for status 1 or 2A (P = .02). A comparable pattern was seen for patient survival in relation to donor age (P = .003), CIT (P = .005), and urgency status (P = .03). Urgent UNOS status, advanced donor age, and prolonged CIT were independently associated with shorter graft and patient survival (P<.05). Functional performance and health-related quality of life were not affected by donor, recipient, or technical characteristics. CONCLUSIONS: Combining advanced donor age, urgent status, and prolonged CIT adversely affects graft and patient survival, and the cumulative effects of these risk factors can be modeled to predict posttransplant survival.


Assuntos
Transplante de Fígado , Qualidade de Vida , Doadores de Tecidos , Adulto , Fatores Etários , Cadáver , Feminino , Sobrevivência de Enxerto , Humanos , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Preservação de Órgãos , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco
10.
Arch Surg ; 140(5): 465-70; discussion 470-1, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15897442

RESUMO

HYPOTHESIS: Living donor liver transplantation (LDLT) results in improved survival compared with deceased whole and split organ transplantation in children. OBJECTIVE: To evaluate the effect of LDLT on graft and patient survival in pediatric liver transplantation. DESIGN: Retrospective cohort. METHODS: Data included all pediatric recipients (aged <18 years) registered in the UNOS (United Network for Organ Sharing) database from October 1, 1987, to May 24, 2004. Covariates predictive of survival by univariate analyses were included in the Cox proportional hazards regression models in a blockwise fashion to determine predictors of survival. RESULTS: Kaplan-Meier graft and patient survival rates were improved in LDLT recipients compared with recipients of deceased whole and split organ transplantations (P<.01). In the initial model (model P<.001), prognostic factors for graft and patient survival included recipient age, race, origin of liver disease, certain pretransplantation laboratory data, medical condition, multiorgan transplantation, retransplantation, recipient-donor ABO blood compatibility, and cold and warm ischemia times. The addition of graft type to the initial covariate set did not significantly change the model (P = .21, covariate P = .09). However, most of the positive prognostic factors identified in the model were inherent characteristics of LDLT recipients and the LDLT procedure. CONCLUSIONS: Graft and patient survival in the pediatric population is better with LDLT than deceased organ transplantation. Factors that contribute to this difference include recipients who are less ill, who have shorter cold and warm ischemia times, and those with a decreased need for retransplantation but not the type of graft per se.


Assuntos
Transplante de Fígado/mortalidade , Doadores Vivos , Pré-Escolar , Estudos de Coortes , Feminino , Sobrevivência de Enxerto , Humanos , Hepatopatias/mortalidade , Hepatopatias/cirurgia , Masculino , Análise Multivariada , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Análise de Sobrevida , Taxa de Sobrevida
11.
Transplantation ; 75(10): 1717-23, 2003 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-12777862

RESUMO

BACKGROUND: Graft dysfunction as a result of preservation injury remains a major clinical problem in liver transplantation. This is related in part to accumulation of mitochondrial calcium. In an attempt to sustain cell and mitochondrial integrity during ischemia, intramitochondrial F(0)F(1) adenosine triphosphate (ATP) synthase reverses its activity and hydrolyzes ATP to maintain the mitochondrial transmembrane potential (mdeltapsi). It is not known how cytoplasmic ATP becomes available for hydrolysis by this enzyme. The authors hypothesized that mitochondrial adenine nucleotide translocator (ANT) reverses its activity during ischemia, making cytoplasmic ATP available for hydrolysis by F(0)F(1) ATP synthase. METHODS: Rat livers were perfused with cold University of Wisconsin solution at 4 degrees C (39.2 degrees F)through the portal vein and processed immediately or after 24 hr of cold storage. Mitochondria were separated by differential centrifugation. ATP-dependent mitochondrial calcium-45 (45Ca)2+ uptake was determined after incubation with ATP (5 mM) or adenosine diphosphate (ADP) (5 mM) with or without 15 microM of bongkrekic acid (BA), an ANT blocker; the nonhydrolyzable analog of ATP (adenosine 5'-beta,gamma-imidotriphosphate [AMP-PNP]) served as the negative control. All measurements were performed in triplicate. Student t test, P<0.05 was taken as significant. RESULTS: Inhibition of ANT by BA prevents mitochondrial Ca2+ accumulation in the presence of ATP and high 45Ca2+ concentrations, and increased extramitochondrial 45Ca2+ stimulated mitochondrial 45Ca2+ uptake in the presence of ATP but not ADP, AMP-PNP, or BA. CONCLUSIONS: These data demonstrate that ANT plays an important role in mitochondrial Ca2+ uptake under ischemic conditions by reversing its activity and allowing transport of extramitochondrial ATP into the matrix for hydrolysis by reversed F(0)F(1) ATP synthase.


Assuntos
Criopreservação , Fígado/metabolismo , Translocases Mitocondriais de ADP e ATP/metabolismo , Trifosfato de Adenosina/fisiologia , Animais , Western Blotting , Ácido Bongcréquico/farmacologia , Cálcio/farmacocinética , Membranas Intracelulares/metabolismo , Masculino , Mitocôndrias/metabolismo , Translocases Mitocondriais de ADP e ATP/antagonistas & inibidores , Concentração Osmolar , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/enzimologia
12.
Surgery ; 136(3): 524-31, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15349097

RESUMO

BACKGROUND: A current limitation of hepatic radiofrequency ablation (RFA) is an inability to detect ablation margins in real time. Thermal injury from RFA alters the biochemical properties governing tissue fluorescence. We hypothesized that the changes in hepatic fluorescence measured during hepatic RFA could be used to detect irreversible hepatocyte damage accurately and to determine ablation margins in real time. METHODS: RFA was performed on healthy pig livers and monitored in vivo simultaneously for fluorescence and temperature by a fiberoptic micro-interrogation probe connected to a spectroscopy system. Ablations were stopped based on previously established real-time fluorescence spectral data, not based on temperature or time. To determine where in the ablated tissue cell death occurred, biopsies for transmission electron microscopy were taken from 4 areas of 3 specimens: (1) nonablated liver, (2) hemorrhagic zone/normal liver interface, (3) hemorrhagic zone/coagulated zone interface, and (4) coagulated zone. In vitro fluorescence emission intensity was determined at each biopsy site. RESULTS: Peak hepatic fluorescence intensity occurred at 470 nm and decreased as RFA progressed. Transmission electron microscopy evidence of irreversible hepatocyte damage occurred at the interface of the coagulation zone and the hemorrhagic zone and correlated with a 87.5% +/- 9% decrease in fluorescence emission intensity. Tissue fluorescent changes from thermal injury were unaffected by tissue cooling. CONCLUSION: Fluorescence spectroscopy accurately detected hepatocellular thermal injury from RFA in real time and can detect irreversible cell damage during tissue thermal therapy.


Assuntos
Ablação por Cateter , Morte Celular/efeitos da radiação , Neoplasias Hepáticas/terapia , Espectrometria de Fluorescência/métodos , Animais , Modelos Animais , Suínos
13.
J Am Coll Surg ; 195(3): 319-26, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12229938

RESUMO

BACKGROUND: The second messengers tyrosine kinase (TK) and protein kinase C (PKC) have been implicated in mediating the cellular signaling cascade during hepatic ischemic preconditioning (IPC). We evaluated the role of TK and PKC on the modulation of the transcription factor nuclear factor kappa B (NFkappaB) and its inhibitor IkappaB alpha during IPC. STUDY DESIGN: Yorkshire pigs underwent routine harvest. IPC livers underwent 15 minutes of ischemia and 15 minutes of in situ perfusion before harvest, with or without pretreatment with a TK inhibitor (genistein) or a PKC inhibitor (chelerythrine). During cold storage and reperfusion, tissue extracts were analyzed for IkappaB alpha phosphorylation and NFkappaB levels and for TK and PKC activity by Western blot. RESULTS: Control pig livers demonstrated no change in the levels of TK, PKC, IkappaB alpha, or NFkappaB before cold ischemia. IPC grafts demonstrated activation of TK and PKC with increased IkappaB alpha phosphorylation and NFkappaB levels before cold ischemia. IPC grafts pretreated with genistein demonstrated inhibition of TK activation but not of PKC activation. Genistein-pretreated grafts also demonstrated inhibition of IkappaB alpha phosphorylation and a lack of NFkappaB translocation to the nucleus throughout the entire experiment. IPC grafts pretreated with chelerythrine demonstrated inhibition of PKC activation but not TK activation. Chelerythrine-pretreated grafts also demonstrated IkappaB alpha phosphorylation before cold ischemia and enhanced nuclear levels of NFkappaB. CONCLUSIONS: Data suggest that the role of TK in IPC might be mediated in part by NFkappaB, but PKC does not depend on NFkappaB for its effect. Two parallel signaling pathways might explain these data.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Proteínas I-kappa B , Precondicionamento Isquêmico , Fígado/irrigação sanguínea , Fígado/fisiologia , NF-kappa B/fisiologia , Proteína Quinase C/fisiologia , Proteínas Tirosina Quinases/fisiologia , Transdução de Sinais/fisiologia , Alcaloides , Animais , Benzofenantridinas , Inibidores Enzimáticos/farmacologia , Genisteína/farmacologia , Modelos Animais , Inibidor de NF-kappaB alfa , Fenantridinas/farmacologia , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Suínos
14.
J Biomed Opt ; 9(5): 1018-27, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15447024

RESUMO

Resection is not a viable treatment option for the majority of liver cancer patients. Alternatives to resection include thermotherapies such as radio-frequency ablation; however, these therapies lack adequate intraoperative feedback regarding the degree and margins of tissue thermal damage. In this proof of principle study, we test the ability of fluorescence and diffuse reflectance spectroscopy to assess local thermal damage in vivo. Spectra were acquired in vivo from healthy canine liver tissue undergoing radio-frequency ablation using a portable fiber-optic-based spectroscopic system. The major observed spectral alterations on thermal coagulation were a red shift in the fluorescence emission peak at 480 nm, a decrease in the overall fluorescence intensity, and an increase in the diffuse reflectance from 450 to 750 nm. Spectral changes were quantified and correlated to tissue histology. We found a good correlation between the proposed spectral correlates of thermal damage and histology. The results of this study suggest that fluorescence and diffuse reflectance spectroscopy show strong potential as tools to monitor liver tissue thermal damage intraoperatively.


Assuntos
Ablação por Cateter/métodos , Temperatura Alta , Fígado/efeitos da radiação , Fígado/cirurgia , Espectrometria de Fluorescência/métodos , Cirurgia Assistida por Computador/métodos , Animais , Queimaduras/diagnóstico , Cães , Estudos de Viabilidade , Hipertermia Induzida/instrumentação , Hipertermia Induzida/métodos , Espectrometria de Fluorescência/instrumentação
15.
J Gastrointest Surg ; 8(3): 313-27, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15019929

RESUMO

Very few areas in medicine have seen as many controversies as the evaluation and treatment of patients with liver diseases. Many novel therapies, often marketed before conclusive demonstration of their efficacy, have been developed to enable selective destruction of liver tumors to minimize the risk of liver failure associated with major surgery. Whether these techniques are effective and result in lesser complications often remains speculative. Persisting challenges in selecting the optimal therapy are the evaluation of the risk of surgery in patients with normal or diseased liver and the preparation for surgery. A panel of hepato-biliary surgeons experienced in the management of complex cases convened at the annual meeting of the American Hepato-Pancreato-Biliary Association in Boston, MA, to address the rapidly evolving field of protective strategies for hepatic surgery.


Assuntos
Hepatectomia , Hepatopatias/cirurgia , Neoplasias Hepáticas/cirurgia , Embolização Terapêutica , Humanos , Cuidados Intraoperatórios , Fígado/irrigação sanguínea , Fígado/fisiologia , Testes de Função Hepática , Regeneração Hepática , Transplante de Fígado , Veia Porta , Complicações Pós-Operatórias/prevenção & controle , Cuidados Pré-Operatórios , Traumatismo por Reperfusão/prevenção & controle , Instrumentos Cirúrgicos , Tomografia Computadorizada por Raios X
16.
J Gastrointest Surg ; 8(6): 653-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15358324

RESUMO

Retrospective studies suggest that resection improves 5-year survival for patients with hepatic carcinoid metastasis (HCM). The purpose of our study was to describe clinical outcomes following resection for HCM, including survival and longitudinal functional quality of life (QOL). We reviewed the records of patients undergoing resection for HCM from 1980 to 2001 at our institution. Outcome measures included tumor symptoms, biochemical tumor markers, functional QOL through Karnofsky functional scores, and survival. Thirteen patients underwent a total of 17 resections. Overall 5-year survival was 85%. Eleven patients were symptomatic, including eight with classic carcinoid syndrome. Nine experienced complete relief of symptoms and two had incomplete relief for 30 +/- 12 months. Eight patients had elevated tumor markers, and 50% of these had postoperative normalization of all tumor markers that persisted to the close of the study. For the 10 patients with longitudinal follow-up available to 54 months, significant improvement in functional QOL was observed at all follow-up time points compared to preresection functional QOL (P < 0.05). Resection of >/=90% tumor volume was significantly associated with more favorable survival and tumor marker normalization compared to resection of <90% tumor volume (P < 0.01 and P < 0.05, respectively), but trajectory of functional QOL improvement did not differ between these two groups (P=0.24). We conclude that resection for HCM is associated with significantly improved and sustained functional QOL and prolonged survival. Resection of >/=90% tumor volume is significantly associated with extended survival and normalization of tumor markers, but is not required for symptomatic or functional QOL improvement.


Assuntos
Tumor Carcinoide/secundário , Tumor Carcinoide/cirurgia , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Qualidade de Vida , Adulto , Idoso , Análise de Variância , Tumor Carcinoide/mortalidade , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida
17.
J Gastrointest Surg ; 8(1): 90-7, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14746840

RESUMO

Our goal was to evaluate fluorodeoxyglucose (FDG) positron emission tomography (PET) in staging patients with biliary tract cancers. Fifty consecutive patients who underwent FDG-PET for suspected cholangiocarcinoma (n=36) or gallbladder carcinoma (n=14) were reviewed. Patients with cholangiocarcinoma were divided into two groups: group 1 had nodular type (mass=1 cm) (n=22) and group 2 had infiltrating type (n=14) cholangiocarcinoma. Thirty-one of 36 patients evaluated for cholangiocarcinoma had cholangiocarcinoma and five did not. Sensitivity was 85% for nodular morphology but only 18% for infiltrating morphology. Sensitivity for metastases was 65% but false negative for carcinomatosis in three of three patients. One false positive result occurred in a patient with primary sclerosing cholangitis who had acute cholangitis. Seven (58%) of 12 patients had FDG uptake along the tract of a biliary stent. FDG-PET led to a change in surgical management in 30% (11 of 36) of patients evaluated for cholangiocarcinoma because of detection of unsuspected metastases. Eleven of 14 patients with gallbladder carcinoma were newly diagnosed by cholecystectomy or another type of exploratory procedure, whereas three patients were undergoing follow-up. Nine had residual gallbladder carcinoma at the time of PET. Sensitivity for gallbladder carcinoma was 78%. Sensitivity for extrahepatic metastases was 50% in eight patients; six of them had carcinomatosis. These data suggest that PET is accurate in predicting the presence of nodular cholangiocarcinoma (mass>1cm) but was not helpful for the infiltrating type. PET was also helpful for detecting residual gallbladder carcinoma following cholecystectomy, but was not helpful in patients with carcinomatosis. Although FDG-PET led to a change in management in 30% of patients with cholangiocarcinoma, it must be interpreted with caution in patients with primary sclerosing cholangitis and with stents in place, as well as in those with known granulomatous disease.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/diagnóstico por imagem , Fluordesoxiglucose F18 , Neoplasias da Vesícula Biliar/diagnóstico por imagem , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
18.
J Gastrointest Surg ; 8(6): 660-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15358325

RESUMO

Radiofrequency ablation (RFA) is an evolving technology used to treat unresectable liver tumors. Currently, there is no accurate method to determine RFA margins in real-time during the procedure. We hypothesized that a fiber-optic based spectroscopic monitoring system could detect thermal damage from RFA in real-time. Fluorescence (F) and diffuse reflectance (Rd) spectra were continuously acquired from within the expected ablation zone during canine hepatic RFA using a fiber-optic microinterrogation probe (MIP). The F and Rd spectral feedback were continuously monitored and ablations were stopped based on changes in spectra alone. After each ablation, the MIP tract was marked with India ink and the ablation zone was excised. The relationship of the MIP to the zone of ablation was examined grossly and microscopically. F and Rd spectral changes occurred in three characteristic phases as the ablation zone progresses past the MIP. Phase 1 indicates minimal deviation from normal lives. Phase 2 occurs as the MIP lies within the hemorrhagic zone of the ablated tissue. Phase 3 correlates with complete tissue coagulation. The absolute magnitude of spectral change correlates with the gross and histologic degree of thermal damage. Optical spectroscopy is a technology that allows real-time detection of thermal tissue damage. In this study, both F and Rd spectroscopy accurately defined the advancing hemorrhagic edge of the zone of ablation and the central coagulation zone. These results suggest that F and Rd spectroscopy can be used to create a real-time feedback system to accurately define RFA margins.


Assuntos
Ablação por Cateter , Morte Celular/efeitos da radiação , Fígado/efeitos da radiação , Espectrometria de Fluorescência/métodos , Animais , Cães , Tecnologia de Fibra Óptica , Neoplasias Hepáticas/terapia , Modelos Animais , Fibras Ópticas , Processamento de Sinais Assistido por Computador
19.
Am J Surg ; 188(5): 571-4, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15546572

RESUMO

BACKGROUND: We sought to determine if disparities in survival and health-related quality of life (HRQOL) occurred after solid organ transplantation at our institution. METHODS: Data were extracted from a database including information regarding transplants that took place from 1990 to 2002. The HRQOL was assessed in patients by using the Karnofsky functional performance (FP) index and the Medical Outcomes Study Short Form 36 (SF-36) questionnaire. RESULTS: Data were collected on recipients of liver (n = 413), heart (n = 299), kidney (n = 892), and lung (n = 156). Blacks represented a minority of recipients: liver 7%, heart 8%, kidney 23%, and lung 6%. There were no statistically significant differences in patient survival between blacks and whites. Graft survival differed in kidney only with a 5-year survival: 72% for blacks versus 79% for whites (P <0.001). The FP and HRQOL improved (P <0.05) after transplantation in both groups. There were no differences on measures of the FP or HRQOL. CONCLUSIONS: Blacks had comparable survival and improvement in FP and HRQOL in comparison with whites.


Assuntos
População Negra/estatística & dados numéricos , Rejeição de Enxerto/etnologia , Transplante de Órgãos/etnologia , Qualidade de Vida , População Branca/estatística & dados numéricos , Adulto , Feminino , Sobrevivência de Enxerto , Transplante de Coração/etnologia , Transplante de Coração/mortalidade , Transplante de Coração/normas , Humanos , Transplante de Rim/etnologia , Transplante de Rim/mortalidade , Transplante de Rim/normas , Transplante de Fígado/etnologia , Transplante de Fígado/mortalidade , Transplante de Fígado/normas , Transplante de Pulmão/etnologia , Transplante de Pulmão/mortalidade , Transplante de Pulmão/normas , Masculino , Pessoa de Meia-Idade , Transplante de Órgãos/mortalidade , Transplante de Órgãos/normas , Sistema de Registros , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Estados Unidos
20.
Am Surg ; 70(6): 496-9, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15212401

RESUMO

Radiofrequency ablation (RFA) is well described in the treatment of primary hepatic malignancies and colorectal carcinoma hepatic metastases. A known complication of RFA is the development of hepatic abscess. The management of hepatic abscesses subsequent to RFA for metastatic disease is not well described. A 49-year-old female with pancreatic adenocarcinoma underwent pancreaticoduodenectomy followed by adjuvant chemoradiation. Following 6 months' treatment, a new liver metastasis was identified. It remained stable for 6 months during additional chemotherapy and thereafter was treated with RFA. Three weeks after RFA, the patient presented with malaise and leukocytosis, and a CT scan demonstrated a large hepatic abscess at the site of the RFA. She remained febrile despite needle aspiration and intravenous antibiotics. A percutaneous drain was placed and the symptoms resolved. Contrast injection of the drain 4 weeks later demonstrated resolution of the abscess cavity but communication with the biliary tree. The drain was removed and the tract embolized with Gel-foam to prevent complications of biliary-cutaneous fistula. She remains well without evidence of abscess or disease recurrence. Thus, RFA can be used in treatment of limited isolated hepatic metastases from previously treated pancreatic adenocarcinoma. However, the incidence of hepatic abscess is increased due to bilioenteric anastomosis; extended antibiotic prophylaxis should be considered.


Assuntos
Adenocarcinoma/secundário , Adenocarcinoma/terapia , Ablação por Cateter/efeitos adversos , Drenagem/métodos , Abscesso Hepático/terapia , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/terapia , Feminino , Humanos , Abscesso Hepático/diagnóstico por imagem , Abscesso Hepático/etiologia , Neoplasias Hepáticas/diagnóstico por imagem , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
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