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1.
Am J Transplant ; 17(7): 1843-1852, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28133906

RESUMO

SIMCER was a 6-mo, multicenter, open-label trial. Selected de novo liver transplant recipients were randomized (week 4) to everolimus with low-exposure tacrolimus discontinued by month 4 (n = 93) or to tacrolimus-based therapy (n = 95), both with basiliximab induction and enteric-coated mycophenolate sodium with or without steroids. The primary end point, change in estimated GFR (eGFR; MDRD formula) from randomization to week 24 after transplant, was superior with everolimus (mean eGFR change +1.1 vs. -13.3 mL/min per 1.73 m2 for everolimus vs. tacrolimus, respectively; difference 14.3 [95% confidence interval 7.3-21.3]; p < 0.001). Mean eGFR at week 24 was 95.8 versus 76.0 mL/min per 1.73 m2 for everolimus versus tacrolimus (p < 0.001). Treatment failure (treated biopsy-proven acute rejection [BPAR; rejection activity index score >3], graft loss, or death) from randomization to week 24 was similar (everolimus 10.0%, tacrolimus 4.3%; p = 0.134). BPAR was more frequent between randomization and month 6 with everolimus (10.0% vs. 2.2%; p = 0.026); the rate of treated BPAR was 8.9% versus 2.2% (p = 0.055). Sixteen everolimus-treated patients (17.8%) and three tacrolimus-treated patients (3.2%) discontinued the study drug because of adverse events. In conclusion, early introduction of everolimus at an adequate exposure level with gradual calcineurin inhibitor (CNI) withdrawal after liver transplantation, supported by induction therapy and mycophenolic acid, is associated with a significant renal benefit versus CNI-based immunosuppression but more frequent BPAR.


Assuntos
Everolimo/farmacologia , Rejeição de Enxerto/tratamento farmacológico , Sobrevivência de Enxerto/efeitos dos fármacos , Imunossupressores/farmacologia , Transplante de Fígado/efeitos adversos , Ácido Micofenólico/farmacologia , Tacrolimo/farmacologia , Feminino , Seguimentos , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Prognóstico , Estudos Prospectivos , Fatores de Risco
2.
Am J Transplant ; 15(2): 395-406, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25612492

RESUMO

Between 2003 and 2012, 42 869 first liver transplantations performed in Europe with the use of either University of Wisconsin solution (UW; N = 24 562), histidine-tryptophan-ketoglutarate(HTK; N = 8696), Celsior solution (CE; N = 7756) or Institute Georges Lopez preservation solution (IGL-1; N = 1855) preserved grafts. Alternative solutions to the UW were increasingly used during the last decade. Overall, 3-year graft survival was higher with UW, IGL-1 and CE (75%, 75% and 73%, respectively), compared to the HTK (69%) (p < 0.0001). The same trend was observed with a total ischemia time (TIT) >12 h or grafts used for patients with cancer (p < 0.0001). For partial grafts, 3-year graft survival was 89% for IGL-1, 67% for UW, 68% for CE and 64% for HTK (p = 0.009). Multivariate analysis identified HTK as an independent factor of graft loss, with recipient HIV (+), donor age ≥65 years, recipient HCV (+), main disease acute hepatic failure, use of a partial liver graft, recipient age ≥60 years, no identical ABO compatibility, recipient hepatitis B surface antigen (-), TIT ≥ 12 h, male recipient and main disease other than cirrhosis. HTK appears to be an independent risk factor of graft loss. Both UW and IGL-1, and CE to a lesser extent, provides similar results for full size grafts. For partial deceased donor liver grafts, IGL-1 tends to offer the best graft outcome.


Assuntos
Rejeição de Enxerto/epidemiologia , Sobrevivência de Enxerto/fisiologia , Transplante de Fígado/métodos , Fígado/fisiologia , Soluções para Preservação de Órgãos , Adenosina , Adulto , Alopurinol , Dissacarídeos , Eletrólitos , Europa (Continente) , Feminino , Glucose , Glutamatos , Glutationa , Histidina , Humanos , Incidência , Insulina , Estudos Longitudinais , Masculino , Manitol , Pessoa de Meia-Idade , Análise Multivariada , Cloreto de Potássio , Procaína , Rafinose , Sistema de Registros , Estudos Retrospectivos
5.
Am J Transplant ; 9(3): 610-3, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19260838

RESUMO

Withdrawal of calcineurin inhibitors (CNI) followed by mycophenolate mofetil (MMF) monotherapy after liver transplantation (LT) remains controversial due to the increased risk of acute rejection and graft loss. The aim of the present study, performed in a large cohort of liver-transplanted patients with severe CNI-induced side effects, was to assess renal function recovery, and safety in terms of liver function, of complete CNI withdrawal and replacement by MMF monotherapy. Fifty-two patients treated with MMF monotherapy for CNI-induced toxicity were analyzed. Mean estimated glomerular filtration rate (eGFR) increased significantly during the period of MMF monotherapy, from 37 +/- 10 to 44.7 +/- 15 mL/min/1.73 m(2) at 6 months (p = 0.001) corresponding to a benefit of +17.4% in renal function. eGFR stabilized or improved in 86.5%, 81% and 79% of cases, and chronic renal dysfunction worsened in 13.5%, 19% and 21% of cases, at 6, 12 and 24 months after CNI withdrawal, respectively. Only two patients experienced acute rejection. MMF monotherapy may be efficient at reversing/stabilizing CRD, and appears relatively safe in terms of liver graft function in long-term liver-transplanted patients. However, clinicians must bear in mind the potential risk of rejection and graft loss, and should be very cautious in the management of such 'difficult-to-treat patients'.


Assuntos
Inibidores de Calcineurina , Inibidores Enzimáticos/efeitos adversos , Transplante de Fígado , Ácido Micofenólico/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Calcineurina/metabolismo , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/uso terapêutico
6.
J Gynecol Obstet Biol Reprod (Paris) ; 38(1): 77-82, 2009 Feb.
Artigo em Francês | MEDLINE | ID: mdl-19036533

RESUMO

AIMS: Evaluation of the mini invasiveness and the learning curve of the Prolift technique. MATERIALS AND METHODS: Prospective study. All patients were operated on by the same surgeon. The mini-invasiveness of the procedure was estimated through the evaluation of the intraoperative and immediate postoperative complications. The learning curve was evaluated through the analysis of the operative time. RESULTS: Between January and December 2007. Forty-seven patients were included in the study. Mean follow-up was: 11,8 months. Two cases of bladder injury and two cases of intraoperative bleeding (>500 ml) were reported. One case of vaginal erosion and one case of recurrence of the prolapse occurred during the follow-up. The mean operative time was 62+/-18 min. The mean operative time of the posterior step of the Prolift was 24+/-min and remained stable after the 18th procedure. DISCUSSION: The learning cure of the posterior of the procedure is longer because of the passage of the needles through the ischiorectal foramens. The technique is mini-invasive considered the low rate of intra and immediate postoperative complication and the learning curve short. CONCLUSIONS: Longer follow-up is needed to evaluate the efficacy of the procedure in the long term.


Assuntos
Procedimentos Cirúrgicos em Ginecologia/efeitos adversos , Procedimentos Cirúrgicos em Ginecologia/métodos , Complicações Intraoperatórias/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Prolapso Uterino/cirurgia , Vagina/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Estudos Prospectivos , Implantação de Prótese/efeitos adversos , Implantação de Prótese/métodos , Resultado do Tratamento , Bexiga Urinária/lesões , Prolapso Uterino/classificação
7.
J Visc Surg ; 156(6): 497-506, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31103560

RESUMO

BACKGROUND: Laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en Y gastric bypass (LRYGB) are commonly performed, but few studies have shown superiority of one strategy over the other. OBJECTIVE: Simultaneously compare LSG and LRYGB in terms of weight loss and morbimortality over a 36-month follow-up period. SETTING: University hospital and bariatric surgery centers, France. METHODS: Prospective, comparative study between LSG and RYGBP. The primary endpoint of this study was a joint hypothesis during the 36-month follow-up: the first primary outcome pertained to the frequency of patients with an excess weight loss (EWL) greater than 50% (% EWL>50%) after LSG or RYGB; the second primary outcome was defined as a composite endpoint of at least one major complication. Secondary objectives were regression of comorbidities and improvement in quality of life. RESULTS: Two hundred and seventy-seven patients were included (91 RYGBP, 186 LSG). The mean age was 41.1±11.1 years, and average preoperative body mass index of 45.3±5.5kg/m2. After 36months, the %EWL>50% was not inferior in the case of LSG (82.2%) relative to LRYGB (82.1%); while major complications rates were significantly higher in LRYGB (15.4%) vs. LSG (5.4%, P=0.005). After 36months, all secondary objectives were comparable between groups while only gastroesophageal reflux disease (GERD) increased in LSG group and decreased in LRYGB group. CONCLUSIONS: LSG was found non-inferior to LRYGB with respect to weight loss and was associated with lower risk of major complications during a 3-year follow-up. But GERD increased in LSG group and decreased in LRYGB group.


Assuntos
Gastrectomia , Derivação Gástrica , Complicações Pós-Operatórias/epidemiologia , Redução de Peso , Adulto , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/cirurgia , Dislipidemias/epidemiologia , Dislipidemias/cirurgia , Feminino , Seguimentos , França/epidemiologia , Refluxo Gastroesofágico/epidemiologia , Refluxo Gastroesofágico/cirurgia , Humanos , Hipertensão/epidemiologia , Hipertensão/cirurgia , Masculino , Estudos Prospectivos , Qualidade de Vida , Apneia Obstrutiva do Sono/epidemiologia , Apneia Obstrutiva do Sono/cirurgia
8.
Am J Transplant ; 8(6): 1221-36, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18522548

RESUMO

Liver ischemia-reperfusion injury occurring in orthotopic liver transplantation (OLT) may be responsible for early graft failure. Molecular mechanisms underlying initial poor graft function (IPGF) have been poorly documented in human. The purpose of this study was to identify the major transcriptional alterations occurring in human livers during OLT. Twenty-one RNA extracts derived from liver transplant biopsies taken after graft reperfusion were compared with 7 RNA derived from normal control livers. Three hundred seventy-one genes were significantly modulated and classified in molecular pathways relevant to liver metabolism, inflammatory response, cell proliferation and liver protection. Grafts were then subdivided into two groups based on their peak levels of serum aspartate amino transferase within 72 h after OLT (group 1, non-IPGF: 14 patients; group 2, IPGF: 7 patients). The two corresponding data sets were compared using a supervised prediction method. A new set of genes able to correctly classify 71% of the patients was defined. These genes were functionally associated with oxidative stress, inflammation and inhibition of cell proliferation. This study provides a comprehensive picture of the transcriptional events associated with human OLT and IPGF. We anticipate that such alterations provide a framework for the elucidation of the molecular mechanisms leading to IPGF.


Assuntos
Função Retardada do Enxerto/genética , Perfilação da Expressão Gênica , Hepatopatias/genética , Transplante de Fígado , Traumatismo por Reperfusão/genética , Adulto , Idoso , Feminino , Sobrevivência de Enxerto/genética , Humanos , Fígado , Masculino , Pessoa de Meia-Idade , Transplantes
9.
Transplant Proc ; 40(6): 2038-41, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18675124

RESUMO

Normothermic liver ischemia-reperfusion (I-R) may induce hepatocellular apoptosis. Caspase activation is involved in the initiation and execution of apoptosis. The aim of this study was to determine in vivo caspase activity in normothermic liver I-R in rats. Segmental normothermic ischemia of the liver was induced for 120 minutes in rats. After intravenous injection of the green probe FLIVO, in vivo caspase-3- and -7-specific activity was determined using fluorescence microscopy, in either nonischemic or ischemic liver lobes at 3 and 6 hours after reperfusion. Liver apoptosis was assessed by the deoxynucleotide transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) assay. Fluorescence microscopy showed that in vivo caspase-3- and -7-specific activities were significantly increased (P< .005) in ischemic lobes at 3 and 6 hours of reperfusion, compared with nonischemic liver lobes. Quantitative analysis of apoptotic cells measured by the TUNEL method showed a significant increase among apoptotic cells in ischemic lobes at 3 and 6 hours after reperfusion (P< .005), compared with nonischemic liver lobes. In conclusion, 120-minute normothermic liver I-R resulted in increased caspase-3- and -7-specific activities and in liver cell apoptosis.


Assuntos
Caspase 3/metabolismo , Caspase 7/metabolismo , Caspases/metabolismo , Fígado/citologia , Fígado/fisiologia , Traumatismo por Reperfusão/fisiopatologia , Animais , Apoptose , Fígado/enzimologia , Ratos , Traumatismo por Reperfusão/enzimologia
10.
Transplant Proc ; 40(6): 2042-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18675125

RESUMO

Apoptosis plays an important role in ischemia-reperfusion (I-R) injury during liver transplantation. The hypoxia-inducible factor alpha (HIF-1alpha) may trigger liver apoptosis following I-R through the induction of hypoxically regulated genes. The aim of this study was to evaluate the effect of normothermic liver I-R on HIF-1alpha expression and apoptosis in rats. Segmental normothermic ischemia of the liver was induced in rats for 120 minutes. Liver extracts from either ischemic or nonischemic lobes were prepared at 0, 1, 3, and 6 hours after reperfusion. Liver HIF-1alpha protein expression was examined by Western blot analysis. Liver apoptosis was quantified using terminal deoxynucleotide transferase-mediated deoxyuridine triphosphate nick end labeling assay. Normothermic I-R resulted in a significant (P< .05) increase in liver HIF-1alpha protein levels 1 and 3 hours after reperfusion. Liver apoptosis was significantly (P< .005) increased at 3 and 6 hours after reperfusion. In conclusion, normothermic liver I-R leads to increased liver expression of HIF-1alpha and apoptosis.


Assuntos
Apoptose/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Fígado/fisiologia , Fígado/fisiopatologia , Traumatismo por Reperfusão/fisiopatologia , Animais , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Marcação In Situ das Extremidades Cortadas , Fígado/citologia , Masculino , Ratos , Ratos Endogâmicos Lew
11.
Transplant Proc ; 40(6): 2049-52, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18675127

RESUMO

The bioartificial liver (BAL) represents a promising approach to cell transplantation without immunosuppression as a method to support patients with hepatic insufficiency. The aim of this study was to assess viability and function of cryopreserved encapsulated porcine hepatocytes implanted intraperitoneally in rats without immunosuppression. Isolated porcine hepatocytes were cryopreserved at -196 degrees C for 1 month. Four groups were created: group 1 (n=10), freshly encapsulated porcine hepatocytes cultured in albumin-free medium for 10 days; group 2 (n=10), freshly encapsulated porcine hepatocytes implanted in the rat peritoneum without immunosuppression for 1 month and cultured for 10 days after explantation; group 3 (n=10), cryopreserved encapsulated porcine hepatocytes cultured for 10 days; group 4 (n=10), cryopreserved encapsulated porcine hepatocytes implanted in the rat peritoneum without immunosuppression for 1 month and cultured for 10 days after explantation. We assessed urea and albumin production and hepatocyte viability. The hepatocytes of all groups retained the capacity to produce urea and albumin, although the albumin synthesis was significantly decreased among hepatocytes of group 4 (P< .01). Encapsulated cryopreserved porcine hepatocytes explanted from rat peritoneum after 1 month appeared morphologically viable; their ultrastructure was preserved. In conclusion, long-term cryopreservation of porcine hepatocytes resulted in retention of their biological activity and in significant viability when transplanted into the rat peritoneum without immunosuppression.


Assuntos
Hepatócitos/transplante , Transplante Heterólogo/fisiologia , Animais , Cápsulas , Sobrevivência Celular , Criopreservação/métodos , Feminino , Sobrevivência de Enxerto , Hepatócitos/citologia , Hepatócitos/fisiologia , Terapia de Imunossupressão , Fígado Artificial , Masculino , Cavidade Peritoneal , Ratos , Ratos Endogâmicos Lew , Suínos
12.
J Visc Surg ; 155(4): 259-264, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29289460

RESUMO

Complications related to energy sources in the operating room are not well-recognized or published, despite occasionally dramatic consequences for the patient and the responsible surgeon. The goal of this study was to evaluate the risks and consequences related to use of energy sources in the operating room. PATIENTS AND METHODS: Between 2009 and 2015, 876 adverse events related to health care (AERHC) linked to energy sources in the operating room were declared in the French experience feedback data base "REX". We performed a descriptive analysis of these AERHC and analyzed the root causes of these events and of the indications for non-elective repeat operations, for each energy source. RESULTS: Five different energy sources were used, producing 876 declared AERHC: monopolar electrocoagulation: 614 (70%) AERHC, advanced bipolar coagulation (thermofusion): 137 (16%) AERHC, ultrasonic devices: 69 (8%) AERHC, traditional bipolar electrocoagulation: 32 AERHC, and cold light: 24 AERHC. The adverse events reported were skin burns (27.5% of AERHC), insulation defects (16% of AERHC), visceral burns or perforation (30% of AERHC), fires (11% of AERHC), bleeding (7.5% of AERHC) and misuse or miscellaneous causes (8% of AERHC). For the five energy sources, the root causes were essentially misuse, imperfect training and/or cost-related reasons regarding equipment purchase or maintenance. One hundred and forty-six non-elective procedures (17% of AERHC) were performed for complications related to the use of energy sources in the operating room. CONCLUSION: This study illustrates the risks related to the use of energy sources on the OR and their consequences. Most cases were related to persistent misunderstanding of appropriate usage within the medical and paramedical teams, but complications are also related to administrative decisions concerning the purchase and maintenance of these devices.


Assuntos
Eletrocoagulação/efeitos adversos , Eletrocoagulação/instrumentação , Complicações Intraoperatórias/etiologia , Gestão de Riscos , Procedimentos Cirúrgicos Ultrassônicos/efeitos adversos , Procedimentos Cirúrgicos Ultrassônicos/instrumentação , Bases de Dados Factuais , França/epidemiologia , Humanos , Complicações Intraoperatórias/epidemiologia
13.
Obes Surg ; 17(9): 1189-92, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18074493

RESUMO

BACKGROUND: Abdominal lipectomy is becoming an increasingly common surgical procedure in patients with esthetic deformities resulting from massive weight loss induced by bariatric surgery. Sometimes a midline incisional hernia coexists with the pendulus abdomen. Herein presented is a technique to perform a retromuscular mesh repair of the incisional hernia while sparing the umbilicus. METHODS: The abdominal lipectomy with concomitant retro-muscular mesh repair of a midline incisional hernia is done sparing the vascular supply of the umbilicus on one side only. RESULTS: 5 consecutive women with pendulus abdomen resulting from bariatric surgery-induced massive weight loss and concomitant midline incisional hernia underwent abdominal lipectomy and incisional hernia mesh repair. Mean BMI was 28.6 kg/m2 (range 26-35), one patient was a smoker, and another had type 2 diabetes requiring oral hypoglycemic agents. Two patients had had a previous incisional hernia repair with intraperitoneal mesh. One patient had partial necrosis of the umbilicus and another experienced necrosis of only the epidermis that recovered fully. CONCLUSIONS: The umbilicus can be safely spared during abdominal lipectomy with concomitant midline incisional hernia mesh repair. Recurrent incisional hernia and common risk factors for wound healing such as diabetes and obesity increase the risk of umbilical necrosis.


Assuntos
Hérnia Ventral/cirurgia , Lipectomia/métodos , Obesidade Mórbida/cirurgia , Telas Cirúrgicas , Adulto , Cirurgia Bariátrica , Feminino , Humanos , Pessoa de Meia-Idade , Umbigo
14.
Transplant Proc ; 39(6): 1761-4, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17692605

RESUMO

Pentoxifylline (PTX) has been shown to protect the liver against normothermic ischemia-reperfusion (I-R) injury. The aims of this study were to investigate the action of PTX on tumor necrosis factor alpha (TNFalpha) gene transcription following normothermic liver I-R as well as to evaluate the resulting effects on liver function and survival. A segmental normothermic liver ischemia was induced for 90 minutes. Rats were divided into three groups: group 1, control, Ringer lactate administration; group 2, PTX treatment; group 3, sham-operated control rats. PTX (50 mg/kg) was injected intravenously 30 minutes before induction of ischemia and 30 minutes before reperfusion. The nonischemic liver lobes were resected at the end of ischemia. Survival rates were compared and serum activities of TNFalpha, aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase were measured. Liver histology was assessed 6 hours after reperfusion. Liver TNFalpha mRNA was assessed by polymerase chain reaction amplification at different times after reperfusion. PTX treatment significantly decreased serum activities of TNFalpha and inhibited liver expression of TNFalpha mRNA. The extent of liver necrosis and serum levels of liver enzymes were significantly decreased by PTX treatment, resulting in a significant increase in 7-day survival compared with nontreated control rats. In conclusion, PTX inhibits liver TNFalpha gene transcription, decreases serum TNFalpha levels, and reduces liver injury following normothermic I-R.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Circulação Hepática , Pentoxifilina/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Transcrição Gênica/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética , Animais , Circulação Hepática/efeitos dos fármacos , Masculino , Modelos Animais , Ratos , Ratos Long-Evans , Vasodilatadores/farmacologia
15.
Surg Endosc ; 20(1): 171-3, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16314994

RESUMO

Subtotal colectomy with cecorectal anastomosis represents an interesting alternative to total colectomy with ileorectal anastomosis. Several technical variants to the methods for performing the anastomosis between the cecum and the rectal stump after subtotal colectomy have been reported. The mechanical, antiperistaltic, end-to-end cecorectal anastomosis is safe and easy to perform. The authors aimed to assess the safety and feasibility of this technique performed laparoscopically in a series of four patients. All the procedures were completed laparoscopically. The mean time for surgery was 200 min (range, 180-220 min). There was no mortality and no postoperative complications. The mean hospital stay was 4 days (range, 3-5 days). This technique can be performed laparoscopically with all the advantages inherent to the minimally invasive approach.


Assuntos
Anastomose Cirúrgica , Ceco/cirurgia , Colectomia/métodos , Constipação Intestinal/cirurgia , Laparoscopia , Reto/cirurgia , Adulto , Idoso , Feminino , Humanos , Tempo de Internação , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Fatores de Tempo , Resultado do Tratamento
16.
Transplant Proc ; 38(10): 3362-5, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17175272

RESUMO

The phosphoregulation of signal transduction pathways is a complex series of reactions that modulate the cellular response to ischemia-reperfusion (I-R). The aim of this study was to evaluate the effect of normothermic liver I-R on protein tyrosine phosphorylation, production of angiogenic growth factors, and activation of signal proteins in tyrosine kinase pathways. A segmental normothermic ischemia of the liver was induced in rats by occluding the blood vessels (including the bile duct) to the median and left lateral lobes for 120 minutes. Liver extracts from either ischemic or nonischemic lobes were prepared at 0, 1, 3, and 6 hours after reperfusion. Liver tyrosine phosphorylation of proteins was examined by Western blot analysis, whereas vascular endothelial growth factor (VEGF) mRNA was analyzed by Northern blot. In ischemic liver lobes, VEGF mRNA and total protein levels increased at 1 and 3 hours after reperfusion. Tyrosine phosphorylation of the VEGF receptor Flk-1 and the platelet-derived growth factor receptor (PDGF-R) was increased only at 1 hour after reperfusion, while c-Src tyrosine phosphorylation remained increased at 3 hours and remained up to 6 hours after reperfusion. In conclusion, 1-R led to alterations in protein tyrosine phosphorylation and increased expression of VEGF in rat liver.


Assuntos
Circulação Hepática , Fígado/enzimologia , Proteínas Tirosina Quinases/metabolismo , Traumatismo por Reperfusão/genética , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Regulação da Expressão Gênica , Masculino , Fosfotirosina/metabolismo , Ratos , Ratos Endogâmicos Lew , Traumatismo por Reperfusão/fisiopatologia
17.
J Natl Cancer Inst ; 91(23): 2014-9, 1999 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-10580026

RESUMO

BACKGROUND: The cytosine deaminase gene of Escherichia coli converts the nontoxic compound 5-fluorocytosine into 5-fluorouracil (5-FU), thereby acting as a suicide gene when introduced into cancer cells, killing the cells when they are exposed to 5-fluorocytosine. We analyzed the efficacy of using cytosine deaminase-bearing cancer cells as an autologous tumor vaccine in a rat model that mimics liver metastasis from colon carcinoma. METHODS: We introduced a plasmid vector containing the E. coli cytosine deaminase gene into a BDIX rat colon carcinoma cell line. Intrahepatic injection of the modified cells in syngeneic animals generates a single experimental liver "suicide tumor." We then analyzed the effect of 5-fluorocytosine treatment in terms of regression of cytosine deaminase-expressing cells in vivo as well as protection against wild-type cancer cells. RESULTS: Treatment with 5-fluorocytosine induced regression of cytosine deaminase-expressing (CD+) tumors, with seven of 11 treated animals being tumor free at the end of 30 days and a statistically significant difference in tumor volumes between treated and control animals (two-sided P<.0001). Intrahepatic injection of CD+ cells followed by 5-fluorocytosine treatment rendered the treated animals resistant to challenge with wild-type tumor cells, with no (zero of seven) treated animals developing wild-type tumors in contrast to all (four of four) control animals. Moreover, in animals with established wild-type liver tumors, injection of CD+ tumor cells followed by 5-fluorocytosine treatment produced a statistically significant increase in survival time (two-sided P<.0001). In vivo immunodepletion and immunohistologic analysis of experimental tumors indicate that natural killer cells are the major immune component involved in this antitumor effect. CONCLUSIONS AND IMPLICATIONS: Taken together, these results suggest the potential use of suicide gene-modified tumor cells as therapeutic vaccines against liver metastasis from colon carcinoma.


Assuntos
Antifúngicos/farmacologia , Antimetabólitos/farmacologia , Vacinas Anticâncer , Flucitosina/farmacologia , Terapia Genética , Neoplasias Hepáticas/terapia , Nucleosídeo Desaminases/genética , Animais , Antineoplásicos , Vacinas Anticâncer/farmacologia , Neoplasias do Colo/patologia , Citosina Desaminase , Escherichia coli/enzimologia , Citometria de Fluxo , Fluoruracila , Células Matadoras Naturais , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/secundário , Masculino , Ratos , Transfecção , Células Tumorais Cultivadas
18.
Cancer Res ; 54(20): 5464-6, 1994 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-7923180

RESUMO

Monoclonal antibody SM 92 is involved in the immunophenotype of gastrointestinal and liver cells, SM 43 in ovarian cells, and SM 13 in lung cells. Based on a study of 61 breast adenocarcinoma patients, we found that tumors reacting with SM 92 appear associated with liver metastases, SM 43 with ovarian metastases, and SM 13 with lung metastases. These associations are highly significant. They lend some support to the concept that tumor cells that metastasize tend to go to sites where cells normally have the same surface antigens.


Assuntos
Anticorpos Monoclonais , Neoplasias da Mama/patologia , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Neoplasias Ovarianas/secundário , Anticorpos Monoclonais/imunologia , Antígenos de Neoplasias/imunologia , Antígenos de Superfície/imunologia , Neoplasias da Mama/imunologia , Feminino , Humanos , Imunofenotipagem , Neoplasias Hepáticas/imunologia , Neoplasias Pulmonares/imunologia , Neoplasias Ovarianas/imunologia
19.
Cell Death Differ ; 8(3): 279-88, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11319611

RESUMO

We examined the effects of dexamethasone (DEX) on the apoptotic process in primary cultures of human and rat hepatocytes. DEX prolonged cell viability, inhibited the development of an apoptotic morphology, and stabilised the expression of procaspase-3 in both human and rat hepatocytes. In addition, the inhibition of apoptosis by DEX was strongly correlated with a decrease of caspase-3-like protease activity. Moreover, DEX treatment increased the expression of anti-apoptotic Bcl-2 and Bcl-xL proteins in human and rat hepatocytes, respectively, whereas the expression of pro-apoptotic proteins Bcl-xS or Bad was not detected or remained unchanged. The bcl-xL transcript is regulated at the transcriptional level and its expression paralleled that of Bcl-xL protein in DEX-treated rat hepatocytes. Taken together, these results indicate that this glucocorticoid exerts a protective role on cell survival and it delays apoptosis of human and rat hepatocytes by modulating caspase-3-like protease activity and bcl-2 and bcl-x gene expression.


Assuntos
Apoptose/efeitos dos fármacos , Dexametasona/farmacologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteína bcl-X/biossíntese , Animais , Apoptose/fisiologia , Northern Blotting , Western Blotting , Caspase 3 , Inibidores de Caspase , Caspases/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Hepatócitos/citologia , Humanos , Marcação In Situ das Extremidades Cortadas , Fígado/citologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Regulação para Cima/efeitos dos fármacos , Proteína bcl-X/genética
20.
Cell Death Differ ; 9(9): 945-55, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12181745

RESUMO

To elucidate the biochemical pathways leading to spontaneous apoptosis in primary cultures of human and rat hepatocytes, we examined the activation of the caspase cascade, the expression of Bcl-2-related-proteins and heat shock proteins. Comparisons were made before and after dexamethasone (DEX) treatment. We show that DEX inhibited spontaneous apoptosis in a dose-dependent manner. DEX increases the expression of anti-apoptotic Bcl-2 and Bcl-x(L) proteins, decreases the expression of pro-apoptotic Bax and inhibits Bad translocation thereby preventing the release of cytochrome c, the activation of caspases, and cell death. Although, the expression of Hsp27 and Hsp70 proteins remained unchanged, the oncogenic protein c-Myc is upregulated upon DEX-treatment. These results indicate that DEX mediates its survival effect against spontaneous apoptosis by acting upstream of the mitochondrial changes. Thus, the mitochondrial apoptotic pathway plays a major role in regulating spontaneous apoptosis in these cells. Blocking this pathway therefore may assist with organ preservation for transplant, drug screening, and other purposes.


Assuntos
Apoptose/fisiologia , Dexametasona/farmacologia , Hepatócitos/metabolismo , Hepatopatias/metabolismo , Fígado/metabolismo , Mitocôndrias/metabolismo , Transdução de Sinais/fisiologia , Animais , Apoptose/efeitos dos fármacos , Proteínas de Transporte/efeitos dos fármacos , Proteínas de Transporte/metabolismo , Caspases/efeitos dos fármacos , Caspases/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Proteína de Suscetibilidade a Apoptose Celular/efeitos dos fármacos , Proteína de Suscetibilidade a Apoptose Celular/metabolismo , Grupo dos Citocromos c/efeitos dos fármacos , Grupo dos Citocromos c/metabolismo , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Proteína Ligante Fas , Hepatócitos/efeitos dos fármacos , Humanos , Fígado/efeitos dos fármacos , Fígado/fisiopatologia , Hepatopatias/fisiopatologia , Glicoproteínas de Membrana/efeitos dos fármacos , Glicoproteínas de Membrana/metabolismo , Mitocôndrias/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/fisiologia , Proteínas Proto-Oncogênicas/efeitos dos fármacos , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-myc/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myc/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos , Proteína X Associada a bcl-2 , Proteína de Morte Celular Associada a bcl , Proteína bcl-X
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