RESUMO
PURPOSE: To examine the safety, feasibility, and oncologic control following percutaneous image-guided thermal ablation of hepatocellular carcinoma (HCC) in a transplanted allograft. MATERIALS AND METHODS: Retrospective review was performed to identify patients who underwent liver transplantation for HCC and subsequently underwent percutaneous hepatic thermal ablation for recurrent HCC within the allograft between January 1st, 2000-September 1st, 2016. Eleven patients with hepatic allograft HCC underwent twelve percutaneous thermal ablation procedures to treat 16 lesions. Patient, procedural characteristics, and local oncologic efficacy were reviewed. Complications were characterized via the Common Terminology for Clinically Adverse Events nomenclature [CTCAE] v4.03). RESULTS: Eleven transplant recipients underwent treatment of 16 HCC tumors in their allografts during 12 ablation sessions. Mean follow-up time was 25 months (range 2-96 months). Local oncologic control was achieved in 10 of 11 tumors (91%) with imaging follow-up. One patient (8%) with Roux-en-Y biliary reconstruction developed a major complication with hepatic abscess. CONCLUSION: Thermal ablation of recurrent HCC in transplanted allografts can be accomplished safely with acceptable rates of local control for patients with duct-to-duct biliary reconstruction. Due to the high number of patients deemed surgically unresectable, the morbidity of surgical resection, the side effects of targeted therapies, and significant mortality associated with recurrences in the transplanted allograft, patients may benefit from percutaneous thermal ablative treatments. Further study is needed to assess the role of thermal ablation in allograft HCC recurrences as primary therapy or in a multimodality approach with emerging systemic therapies.
Assuntos
Carcinoma Hepatocelular/cirurgia , Ablação por Cateter/métodos , Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Recidiva Local de Neoplasia/cirurgia , Idoso , Aloenxertos , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Fígado/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transplante Homólogo , Resultado do TratamentoRESUMO
UNLABELLED: The presence of an intrahepatic cholangiocarcinoma (iCCA) in a cirrhotic liver is a contraindication for liver transplantation in most centers worldwide. Recent investigations have shown that "very early" iCCA (single tumors ≤2 cm) may have acceptable results after liver transplantation. This study further evaluates this finding in a larger international multicenter cohort. The study group was composed of those patients who were transplanted for hepatocellular carcinoma or decompensated cirrhosis and found to have an iCCA at explant pathology. Patients were divided into those with "very early" iCCA and those with "advanced" disease (single tumor >2 cm or multifocal disease). Between January 2000 and December 2013, 81 patients were found to have an iCCA at explant; 33 had separate nodules of iCCA and hepatocellular carcinoma, and 48 had only iCCA (study group). Within the study group, 15/48 (31%) constituted the "very early" iCCA group and 33/48 (69%) the "advanced" group. There were no significant differences between groups in preoperative characteristics. At explant, the median size of the largest tumor was larger in the "advanced" group (3.1 [2.5-4.4] versus 1.6 [1.5-1.8]). After a median follow-up of 35 (13.5-76.4) months, the 1-year, 3-year, and 5-year cumulative risks of recurrence were, respectively, 7%, 18%, and 18% in the very early iCCA group versus 30%, 47%, and 61% in the advanced iCCA group, P = 0.01. The 1-year, 3-year, and 5-year actuarial survival rates were, respectively, 93%, 84%, and 65% in the very early iCCA group versus 79%, 50%, and 45% in the advanced iCCA group, P = 0.02. CONCLUSION: Patients with cirrhosis and very early iCCA may become candidates for liver transplantation; a prospective multicenter clinical trial is needed to further confirm these results. (Hepatology 2016;64:1178-1188).
Assuntos
Neoplasias dos Ductos Biliares/cirurgia , Carcinoma Hepatocelular/cirurgia , Colangiocarcinoma/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Idoso , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/mortalidade , Colangiocarcinoma/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
When transplanted simultaneously, the liver allograft has been thought to have an immunoprotective role on other organs; however, detailed analyses in simultaneous heart-liver transplantation (SHLT) have not been done to date. We analyzed patient outcomes and incidence of immune-mediated injury in 22 consecutive SHLT versus 223 isolated heart transplantation (IHT) recipients between January 2004 and December 2013, by reviewing 3912 protocol- and indication-specific cardiac allograft biopsy specimens. Overall survival was similar (86.4%, 86.4%, and 69.1% for SHLT and 93.3%, 84.7%, and 70.0% for IHT at 1, 5, and 10 years; p = 0.83). Despite similar immunosuppression, the incidence of T cell-mediated rejection (TCMR) was lower in SHLT (31.8%) than in IHT (84.8%) (p < 0.0001). Although more SHLT patients had preexisting donor-specific HLA antibody (22.7% versus 8.1%; p = 0.04), the incidence of antibody-mediated rejection was not different in SHLT compared with IHT (4.5% versus 14.8%, p = 0.33). While the left ventricular ejection fraction was comparable in both groups at 5 years, the incidence and severity of cardiac allograft vasculopathy were reduced in the SHLT recipients (42.9% versus 66.8%, p = 0.03). Simultaneously transplanted liver allograft was associated with reduced risk of TCMR (odds ratio [OR] 0.003, 95% confidence interval [CI] 0-0.02; p < 0.0001), antibody-mediated rejection (OR 0.04, 95% CI 0-0.46; p = 0.004), and cardiac allograft vasculopathy (OR 0.26, 95% CI 0.07-0.84; p = 0.02), after adjusting for other risk factors. These data suggest that the incidence of alloimmune injury in the heart allograft is reduced in SHLT recipients.
Assuntos
Aloenxertos/imunologia , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/imunologia , Transplante de Coração , Transplante de Fígado , Complicações Pós-Operatórias/prevenção & controle , Feminino , Seguimentos , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/imunologia , Cardiopatias/cirurgia , Humanos , Incidência , Hepatopatias/cirurgia , Masculino , Pessoa de Meia-Idade , Minnesota/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/imunologia , Prognóstico , Fatores de RiscoRESUMO
Determining risk for recurrence of hepatocellular carcinoma (HCC) following liver transplantation (LT) is an important clinical need. We assessed consecutive patients who underwent LT for HCC following sequential transarterial chemoembolization (TACE). Treatment response was assessed using modified response evaluation criteria in solid tumors (mRECIST) categories: complete response (CR), partial response (PR), stable disease (SD) and progressive disease (PD). Cox proportional hazard models were used to predict HCC recurrence. One hundred seventy-three patients underwent TACE and imaging to assess response prior to LT. TACE responses were: CR = 23.7%, PR = 24.3%, SD = 27.7% and PD = 24.3%. Five-year HCC recurrence rate was 5.3% in patients responding to TACE (CR/PR), versus 17.6%, among patients who did not respond (SD/PD, p = 0.014). In multivariate analysis, independent pre-LT predictors of recurrence were response to TACE and largest radiologic size of tumor (>3 cm vs. ≤3 cm). HCC recurrence rate for patients with tumor size >3 cm and no response to TACE was 35.8%, compared with 1.9% for patients with tumor size ≤3 cm and response to TACE (p = 0.0007). We conclude that mRECIST criteria and tumor size differentiate patients with high or low likelihood of HCC recurrence after LT. These findings raise the possibility of incorporating response to TACE and largest tumor size to identify patients at highest risk for HCC recurrence.
Assuntos
Carcinoma Hepatocelular/patologia , Quimioembolização Terapêutica , Neoplasias Hepáticas/patologia , Idoso , Carcinoma Hepatocelular/terapia , Feminino , Humanos , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , RecidivaRESUMO
The current liver allocation system, introduced in 2002, decreased the importance of waiting time for allocation priorities; the number of active wait-listed candidates and median waiting times were immediately reduced. However, the total number of adult wait-listed candidates has increased since 2002, and median waiting time has increased since 2006. Pretransplant mortality rates have been stable, but the number of candidates withdrawn from the list as being too sick to undergo transplant nearly doubled between 2009 and 2011. Deceased donation rates have remained stable, with an increasing proportion of expanded criteria donors. Living donation has decreased over the past 10 years. Transplant outcomes remain robust, with continuously improving graft survival rates for deceased donor, living donor, and donation after circulatory death livers. Numbers of new and prevalent pediatric candidates on the waiting list have decreased. Pediatric pretransplant mortality has decreased, most dramatically for candidates aged less than 1 year. The transplant rate has increased since 2002, and is highest in candidates aged less than 1 year. Graft survival continues to improve for pediatric recipients of deceased donor and living donor livers. Incidence of acute rejections increases with time after transplant. Posttransplant lymphoproliferative disorder remains an important concern in pediatric recipients.
Assuntos
Transplante de Fígado , Humanos , Imunossupressores/administração & dosagem , Doadores Vivos , Doadores de Tecidos , Listas de EsperaRESUMO
Although mortality rates following liver transplantation (LT) are well described, there is a lack of detailed, prospective studies determining patterns of and risk factors for long-term mortality. We analyzed the multicenter, prospectively obtained The National Institute of Diabetes and Digestive and Kidney Diseases LT Database of 798 transplant recipients from 1990 to 1994 (follow-up 2003). Overall, 327 recipients died. Causes of death >1 year: 28% hepatic, 22% malignancy, 11% cardiovascular, 9% infection, 6% renal failure. Renal-related death increased dramatically over time. Risk factors for death >1 year (univariate): male gender, age/decade, pre-LT diabetes, post-LT diabetes, post-LT hypertension, post-LT renal insufficiency, retransplantation >1 year, pre-LT malignancy, alcoholic disease (ALD) and metabolic liver disease, with similar risks noted for death >5 years. Hepatitis C, retransplantation, post-LT diabetes, hypertension and renal insufficiency were significant risk factors for liver-related death. Cardiac deaths associated with age, male gender, ALD, cryptogenic disease, pre-LT hypertension and post-LT renal insufficiency. In summary, the leading causes of late deaths after transplant were graft failure, malignancy, cardiovascular disease and renal failure. Older age, diabetes and renal insufficiency identified patients at highest risk of poor survival overall. Diligent management of modifiable post-LT factors including diabetes, hypertension and renal insufficiency may impact long-term mortality.
Assuntos
Transplante de Fígado/efeitos adversos , Transplante de Fígado/mortalidade , Alcoólicos , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/mortalidade , Diabetes Mellitus/induzido quimicamente , Diabetes Mellitus/etiologia , Diabetes Mellitus/mortalidade , Feminino , Seguimentos , Hepatite C/induzido quimicamente , Hepatite C/etiologia , Hepatite C/mortalidade , Humanos , Hipertensão/induzido quimicamente , Hipertensão/etiologia , Hipertensão/mortalidade , Rim , Transplante de Rim/mortalidade , Fígado , Hepatopatias/etiologia , Hepatopatias/mortalidade , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , National Institute of Diabetes and Digestive and Kidney Diseases (U.S.) , Estudos Prospectivos , Insuficiência Renal/induzido quimicamente , Insuficiência Renal/etiologia , Insuficiência Renal/mortalidade , Fatores de Risco , Resultado do Tratamento , Estados UnidosRESUMO
Liver transplantation numbers in the United States remained constant from 2004 to 2007, while the number of waiting list candidates has trended down. In 2007, the waiting list was at its smallest since 1999, with adults > or =50 years representing the majority of candidates. Noncholestatic cirrhosis was most commonly diagnosed. Most age groups had decreased waiting list death rates; however, children <1 year had the highest death rate. Use of liver allografts from donation after cardiac death (DCD) donors increased in 2007. Model for end-stage liver disease (MELD)/pediatric model for end-stage liver disease (PELD) scores have changed very little since 2002, with MELD/PELD <15 accounting for 75% of the waiting list. Over the same period, the number of transplants for MELD/PELD <15 decreased from 16.4% to 9.8%. Hepatocellular carcinoma exceptions increased slightly. The intestine transplantation waiting list decreased from 2006, with the majority of candidates being children <5 years old. Death rates improved, but remain unacceptably high. Policy changes have been implemented to improve allocation and recovery of intestine grafts to positively impact mortality. In addition to evaluating trends in liver and intestine transplantation, we review in depth, issues related to organ acceptance rates, DCD, living donor transplantation and MELD/PELD exceptions.
Assuntos
Intestinos/transplante , Transplante de Fígado/estatística & dados numéricos , Sistema ABO de Grupos Sanguíneos , Carcinoma Hepatocelular/cirurgia , Criança , Pré-Escolar , Etnicidade , Feminino , Humanos , Lactente , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/mortalidade , Masculino , Grupos Raciais , Taxa de Sobrevida , Sobreviventes , Transplante Homólogo/mortalidade , Transplante Homólogo/estatística & dados numéricos , Estados Unidos/epidemiologia , Listas de EsperaRESUMO
UNLABELLED: Liver transplantation alone for unresectable hilar cholangiocarcinoma (CCA) is fraught with frequent recurrence and poor long-term survival. The Mayo Clinic developed a novel therapeutic protocol combining neoadjuvant chemoradiation and orthotopic liver transplantation (OLT) in 1993 to treat patients with unresectable hilar CCA or CCA arising in the setting of PSC. AIM: We recently reviewed our experience over the past 14 years with the specific aim to evaluate the long-term outcomes of CCA patients treated according to our study protocol. METHODS: We analyzed data from all patients enrolled in the Mayo Clinic liver transplant protocol since 1993. Statistical data analysis of recurrence and survival rates was performed using the Kaplan-Meier method. RESULTS: 148 patients were enrolled in the protocol. Of 90 patients who completed neoadjuvant therapy and subsequent OLT, 71 are alive and 19 have died--only 8 due to recurrent CCA. Nineteen patients are awaiting OLT and 39 were removed from the protocol owing to disease progression or death. Overall, 1-, 3-, and 5-year patient survival was 82%, 63%, and 55%, respectively; 1-, 3-, and 5-year survival after OLT was 90%, 80%, and 71%. CONCLUSIONS: Neoadjuvant chemoradiation and OLT achieves significantly lower recurrence and higher long-term survival rates than resection, OLT alone, or medical treatment in hilar CCA. Additional experience at independent transplant centers is necessary to confirm these encouraging results, address the role of neoadjuvant therapy and liver transplantation versus conventional resection, determine appropriate inclusion/exclusion criteria, and define the risk of disease progression while awaiting transplantation.
RESUMO
Recurrent hepatitis C virus (HCV) infection is a major cause of morbidity and mortality after liver transplantation for HCV-related end stage liver disease. Although previous studies have shown a short-term effect of interferon-based treatment on fibrosis progression, it is unclear whether this translates to improved graft survival. We evaluated whether treatment of recurrent HCV leads to an improved graft survival. Cohort study included consecutive HCV patients who underwent liver transplantation between 1 January 1995 and 1 January 2005 in the Mayo Clinic, Rochester, MN. Two hundred and fifteen patients were included in the study. During a median follow-up of 4.4 years (interquartile range 2.2-6.6), 165 patients (77%) had biopsy-proven recurrent HCV infection confirmed by serum HCV RNA testing. Seventy-eight patients were treated. There were no differences in MELD-score, fibrosis stage or time towards HCV recurrence between treated and untreated patients at time of recurrence. There was a trend for greater frequency of acute cellular rejection among untreated patients. The incidence of graft failure was lower for patients treated within 6 months of recurrence compared to patients not treated within this time-period (log rank p = 0.002). Time-dependent multivariate Cox regression analysis showed that treatment of recurrent HCV infection was statistically significantly associated with a decreased risk of overall graft failure (hazard ratio 0.34; CI 0.15-0.77, p = 0.009) and a decreased risk of graft failure due to recurrent HCV (hazard ratio 0.24; CI 0.08-0.69, p = 0.008). In conclusion, although a cause and effect relationship cannot be established, treatment of recurrent HCV infection after liver transplantation is associated with a reduced risk of graft failure.
Assuntos
Hepatite C/patologia , Hepatite C/terapia , Interferon-alfa/uso terapêutico , Transplante de Fígado/efeitos adversos , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Antivirais/administração & dosagem , Feminino , Rejeição de Enxerto , Hepatite C/tratamento farmacológico , Humanos , Interferon alfa-2 , Transplante de Fígado/métodos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Proteínas Recombinantes , Recidiva , Análise de Regressão , Risco , Resultado do TratamentoRESUMO
BACKGROUND: The aim was to evaluate outcomes in patients with ulcerative colitis complicated by primary sclerosing cholangitis (PSC) who required ileal pouch-anal anastomosis (IPAA) and orthotopic liver transplantation (OLT). METHODS: A retrospective analysis was performed of 32 patients undergoing both IPAA and OLT between 1980 and 2006. Data were collected regarding demographics, indication for surgery, postoperative complications, and outcome of IPAA and OLT. RESULTS: Thirty-day mortality after either procedure was nil. The median preoperative Model for End-stage Liver Disease (MELD) score for the group with initial IPAA was 8 (range 6-20) and the postoperative score was 11 (range 6-19). At 1 and 10 years, 32 and 26 of the 32 liver grafts had survived, and 31 and 30 of the 32 pouches, respectively. Fourteen patients require daily medical therapy for chronic pouchitis. At a median follow-up of 3.6 (range 0.2-16.2) years after the second of two procedures, responding patients reported a median of 5.5 stools per day and 2 stools per night. CONCLUSION: IPAA and OLT are feasible and safe in patients requiring both procedures for ulcerative colitis and PSC. Functional outcomes are stable over time, despite an increased risk of chronic pouchitis.
Assuntos
Canal Anal/cirurgia , Colangite Esclerosante/complicações , Colite Ulcerativa/complicações , Bolsas Cólicas , Transplante de Fígado , Adolescente , Adulto , Anastomose Cirúrgica , Colite Ulcerativa/cirurgia , Intervalo Livre de Doença , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pouchite/etiologia , Resultado do TratamentoRESUMO
The link between obesity and renal disease is unclear, and there is no consensus as to whether obese individuals are at increased risk for kidney disease after living kidney donation if they otherwise meet acceptance criteria. We retrospectively studied time-zero (implantation) biopsies in 49 obese (body mass index (BMI) > or = 30 kg/m2) and 41 non-obese (BMI < 30 kg/m2) renal donors that met acceptance criteria. We found that our obese donor population had higher systolic blood pressure (P < 0.001 vs non-obese) and higher absolute iothalamate clearance (P = 0.001 vs non-obese) before donation. The obese donors had larger glomerular planar surface area compared to non-obese controls (P = 0.017), and this parameter correlated with patient weight and urinary microalbumin excretion. Detailed examination of the biopsies revealed that although most histologic findings were similar between groups, the obese donors had more tubular dilation (P = 0.01), but less tubular vacuolization (P = 0.02) than the non-obese controls. There was also a trend toward more arterial hyalinosis in the obese patients than controls (P = 0.08). From these data, our studies detected subtle differences in donor organs obtained from obese compared to non-obese individuals. Further studies should be carried out to quantify the long-term impact of these findings.
Assuntos
Glomérulos Renais/citologia , Glomérulos Renais/patologia , Doadores Vivos , Obesidade/patologia , Adulto , Idoso , Biópsia , Índice de Massa Corporal , Feminino , Seguimentos , Taxa de Filtração Glomerular/fisiologia , Humanos , Glomérulos Renais/fisiologia , Transplante de Rim/patologia , Masculino , Pessoa de Meia-Idade , Nefrectomia/efeitos adversos , Obesidade/fisiopatologia , Tamanho do Órgão , Complicações Pós-Operatórias/prevenção & controle , Estudos RetrospectivosRESUMO
BACKGROUND: We formulated a clinical pathway (CP) for elective laparoscopic cholecystectomy (LC), which included the following preoperative evaluation: history and physical (H&P), right upper quadrant ultrasound (US), and liver function tests (LFTs). We hypothesized that routine LFTs did not alter management beyond that dictated by H&P and US, and could be excluded from the CP. METHODS: The study involved 387 consecutive patients undergoing elective LC. Abnormalities in the preoperative evaluation were compared with the finding of choledocholithiasis or other unexpected outcomes. RESULTS: In 187 (48%) patients, abnormalities were found by H&P (n = 7), US (n = 13), and LFTs (n = 177). Seven patients (2%) had documented choledocholithiasis; two had abnormal H & P; three had abnormal US; and four had abnormal LFTs. No patient with choledocholithiasis had abnormal LFTs but normal H&P and US. CONCLUSIONS: Routine LFTs before elective LC are not cost effective. Before LC H&P and US are warranted, but LFTs do not add any useful information and should not be routinely measured.
Assuntos
Colecistectomia Laparoscópica/métodos , Colelitíase/cirurgia , Testes de Função Hepática , Procedimentos Desnecessários , Adulto , Colangiopancreatografia Retrógrada Endoscópica , Colelitíase/sangue , Protocolos Clínicos , Testes Diagnósticos de Rotina , Procedimentos Cirúrgicos Eletivos/métodos , Feminino , Humanos , Masculino , Estudos ProspectivosRESUMO
BACKGROUND: Tumor necrosis factor (TNF)-alpha is a critical effector of lipopolysaccharide (LPS)-induced acute lung injury, and its effects are mediated by two structurally related receptors, RI and RII. Cellular adhesion molecules and C-X-C chemokines (Keratinocyte chemoattractant (KC) and macrophage inflammatory protein [MIP]-2) regulate tissue neutrophil polymorphonuclear neutrophil (PMN) accumulation in a multitude of inflammatory states. We hypothesized that TNFRI signaling dictates PMN accumulation in the lung via regulation of chemokine molecule production. Therefore, the purposes of this study were to (1) delineate LPS-induced lung TNF-alpha production and (2) characterize the contribution of both TNF receptors to lung chemokine production and neutrophil influx following systemic LPS. METHODS: Wild-type or TNFRI and TNFRII knockout (KO) mice were injected with vehicle (saline) or LPS (Escherichia coli 0.5 mg/kg intraperitoneally). After 2, 4, 6, or 24 h, lungs were analyzed for TNF-alpha and chemokine (KC and MIP-2) protein expression (enzyme-linked immunosorbent assay) and PMN accumulation (myeloperoxidase assay). RESULTS: There was an increase in total lung TNF-alpha (vehicle, 5.0 +/- 1.2 pg/mg total protein vs LPS, 950 +/- 318; P < 0.05) after LPS. Lung chemokine production and PMN accumulation were also increased compared to vehicle-injected mice. Lung chemokine production and PMN accumulation were significantly lower in TNFRI KO, but not TNFRII KO, mice, despite no difference in TNF-alpha production (TNFRI KO, 925 +/- 301 vs TNFRII KO, 837 +/- 267, P = 0.82). CONCLUSIONS: Acute lung injury following systemic LPS administration is characterized by increased lung (1) TNF-alpha production, (2) C-X-C chemokine production, and (3) neutrophil accumulation. The maximal effect of LPS-induced lung neutrophil accumulation appears to be dependent upon the TNFRI receptor but not the TNFRII receptor. .
Assuntos
Antígenos CD/fisiologia , Quimiocinas/biossíntese , Lipopolissacarídeos/toxicidade , Pulmão/efeitos dos fármacos , Neutrófilos/fisiologia , Receptores do Fator de Necrose Tumoral/fisiologia , Animais , Movimento Celular/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Camundongos , Receptores Tipo I de Fatores de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral , Fator de Necrose Tumoral alfa/biossínteseRESUMO
Expression of heat shock proteins (HSP) is an adaptive response to cellular stress. Stress induces tumor necrosis factor (TNF)-alpha production. In turn, TNF-alpha induces HSP70 expression. However, osmotic stress or ultraviolet radiation activates TNF-alpha receptor I (TNFR-I) in the absence of TNF-alpha. We postulated that TNF-alpha receptors are involved in the induction of HSP70 by cellular stress. Peritoneal Mphi were isolated from wild-type (WT), TNF-alpha knockout (KO), and TNFR (I or II) KO mice. Cells were cultured overnight and then heat stressed at 43 +/- 0.5 degrees C for 30 min followed by a 4-h recovery at 37 degrees C. Cellular HSP70 expression was induced by heat stress or exposure to endotoxin [lipopolysaccharide (LPS)] as determined by immunoblotting. HSP70 expression induced by either heat or LPS was markedly decreased in TNFR-I KO Mphi, whereas TNFR-II KO Mphi exhibited HSP70 expression comparable to that in WT mice. Expression of HSP70 after heat stress in TNF-alpha KO Mphi was also similar to that in WT mice, suggesting that induction of HSP70 by TNFR-I occurs independently of TNF-alpha. In addition, levels of steady-state HSP70 mRNA were similar by RT-PCR in WT and TNFR-I KO Mphi despite differences in protein expression. Furthermore, the effect of TNFR-I appears to be cell specific, since HSP70 expression in splenocytes isolated from TNFR-I KO was similar to that in WT splenocytes. These studies demonstrate that TNFR-I is required for the synthesis of HSP70 in stressed Mphi by a TNF-independent mechanism and support an intracellular role for TNFR-I.
Assuntos
Proteínas de Choque Térmico HSP70/biossíntese , Macrófagos/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Células Cultivadas , Regulação da Expressão Gênica , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Temperatura Alta , Immunoblotting , Camundongos , Camundongos Knockout , RNA/metabolismo , Receptores do Fator de Necrose Tumoral/genética , Baço/citologia , Fator de Necrose Tumoral alfa/genéticaRESUMO
Chemokines stimulate the influx of leukocytes into tissues. Their production is regulated by nuclear factor-kappaB (NF-kappaB), an inducible transcription factor under the control of inhibitory factor kappaB-alpha (IkappaB-alpha). We have previously demonstrated that L-arginine (L-Arg) attenuates neutrophil accumulation and pulmonary vascular injury after administration of lipopolysaccharide (LPS). We hypothesized that L-Arg would attenuate the production of lung chemokines by stabilizing IkappaB-alpha and preventing NF-kappaB DNA binding. We examined the effect of L-Arg on chemokine production, IkappaB-alpha degradation, and NF-kappaB DNA binding in the lung after systemic LPS. To block nitric oxide (NO) production, a NO synthase inhibitor was given before L-Arg. LPS induced the production of chemokine protein and mRNA. L-Arg attenuated the production of chemokine protein and mRNA, prevented the decrease in IkappaB-alpha levels, and inhibited NF-kappaB DNA binding. NO synthase inhibition abolished the effects of L-Arg on all measured parameters. Our results suggest that L-Arg abrogates chemokine protein and mRNA production in rat lung after LPS. This effect is dependent on NO and is mediated by stabilization of IkappaB-alpha levels and inhibition of NF-kappaB DNA binding.
Assuntos
Arginina/farmacologia , Quimiocinas CXC , Quimiocinas/antagonistas & inibidores , Quimiocinas/biossíntese , Peptídeos e Proteínas de Sinalização Intercelular , Lipopolissacarídeos/farmacologia , Pulmão/metabolismo , Animais , Arginina/sangue , Quimiocina CXCL1 , Quimiocina CXCL2 , Quimiocinas/genética , Quimiocinas/metabolismo , Fatores Quimiotáticos/genética , Fatores Quimiotáticos/metabolismo , DNA/metabolismo , Substâncias de Crescimento/genética , Substâncias de Crescimento/metabolismo , Proteínas I-kappa B/metabolismo , Masculino , NF-kappa B/metabolismo , Nitratos/metabolismo , Nitritos/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
BACKGROUND: Paradoxically, patients with noninsulin-dependent diabetes mellitus experience a higher cardiovascular mortality rate than patients with insulin-dependent diabetes mellitus. We have shown that K(ATP) channel inhibition, with oral sulfonylureas, prevents myocardial preconditioning and may explain the paradox of cardiovascular death in patients with noninsulin-dependent diabetes mellitus. Cardiac preconditioning is an attractive protective strategy against any elective ischemia/reperfusion (I/R) injury. The relationship between the K(ATP) channels and human myocardial preconditioning has not previously been elucidated. METHODS: Human atrial trabeculae were harvested, placed in organ baths, and paced (1 Hz). Developed force was recorded during simulated 37 degrees C I/R (30/45 or 45/60 minutes). Before I/R, trabeculae were treated transiently with a selective mitochondrial K(ATP) channel opener for 5 minutes, followed by a 10-minute washout, or were exposed to the channel opener throughout ischemia. Recovery of function is expressed as percentage of baseline developed force. Conserved creatine kinase activity (units per gram of wet tissue) was measured at the end of reperfusion as an indicator of cellular protection. RESULTS: Transient mitochondrial K(ATP) channel opening provided protection from both I/R insults. Surprisingly, there was no protection afforded by continuous mitochondrial K(ATP) channel opening. CONCLUSIONS: Transient selective mitochondrial K(ATP) channel opening protects both viability and function of human myocardium against I/R injury, although prolonged opening of the mitochondrial K(ATP) channel does not. These results reinforce the concept of preconditioning as a transient event that must be completed before the onset of ischemia.
Assuntos
Precondicionamento Isquêmico Miocárdico , Mitocôndrias Cardíacas/fisiologia , Canais de Potássio/fisiologia , Trifosfato de Adenosina/metabolismo , Ponte Cardiopulmonar , Tecido Conjuntivo/fisiologia , Tecido Conjuntivo/fisiopatologia , Ponte de Artéria Coronária , Creatina Quinase/metabolismo , Diazóxido/farmacologia , Átrios do Coração/efeitos dos fármacos , Átrios do Coração/fisiopatologia , Frequência Cardíaca , Humanos , Técnicas In Vitro , Ativação do Canal Iônico , Reperfusão MiocárdicaRESUMO
OBJECTIVES: Recently, the mitochondrial adenosine triphosphate-sensitive potassium channel has been suggested to be the final common effector of myocardial preconditioning. The purpose of this study is to determine whether selective mitochondrial adenosine triphosphate-sensitive potassium channel activation alone can precondition human myocardium from an ischemia/reperfusion insult. METHODS: Isolated human right atrial trabeculae were placed in tissue baths, paced, and subjected to 30 minutes of normothermic hypoxia (ischemia) followed by 45 minutes of reoxygenation (reperfusion). Trabeculae were preconditioned with a selective mitochondrial adenosine triphosphate-sensitive potassium channel opener (diazoxide 30 micromol/L) or a nonselective purinergic agonist, adenosine (125 micromol/L), for 5 minutes (adenosine) followed by a 10-minute washout period. Developed force at end reperfusion (mean +/- standard error) was compared with baseline, and tissue creatine kinase and adenosine triphosphate levels were measured after ischemia/reperfusion. RESULTS: Trabeculae subjected to ischemia/reperfusion exhibited 30% +/- 2% of baseline developed force, whereas trabeculae subjected to selective adenosine triphosphate-sensitive potassium channel opening (diazoxide) and nonselective purinergic agonist (adenosine) recovered to 55% +/- 7% and 46% +/- 3% of baseline developed force, respectively. Tissue creatine kinase activity was preserved in both the diazoxide- and adenosine-treated trabeculae (5.4 +/- 12 and 5.4 +/- 14 micromol/L per gram wet tissue) compared with ischemia/reperfusion (1.8 +/- 0.2 U/mg wet tissue). Adenosine triphosphate levels at end reperfusion were also increased in the trabeculae treated with selective (diazoxide) and nonselective (adenosine) adenosine triphosphate-sensitive potassium channel opener (4.1 +/- 0.01 and 4. 4 +/- 0.2 micromol/L per gram wet tissue) compared with trabeculae subjected to ischemia/reperfusion (1.5 +/- 0.1 micromol/L per gram wet tissue). CONCLUSIONS: These results suggest that selective mitochondrial adenosine triphosphate-sensitive potassium channel activation preconditions human myocardium and the protection conferred is equal to that of adenosine preconditioning. Targeted openers of mitochondrial adenosine triphosphate- sensitive potassium channels promote constructive protection of myocellular energy levels, contractile function, and cellular viability in human myocardium after ischemia/reperfusion.
Assuntos
Trifosfato de Adenosina/farmacologia , Mitocôndrias Cardíacas/metabolismo , Isquemia Miocárdica/fisiopatologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Canais de Potássio/efeitos dos fármacos , Adenosina/farmacologia , Trifosfato de Adenosina/metabolismo , Análise de Variância , Creatina Quinase/metabolismo , Diazóxido/farmacologia , Humanos , Miocárdio/metabolismo , Vasodilatadores/farmacologiaRESUMO
Iron EDTA [sodium iron (Fe(3+)) ethylenediaminetetraacetic acid (EDTA)], shown to have a significant beneficial effect on iron status by increasing iron bioavailability in human diets, has been proposed for use as a fortificant in certain grain-based products including breakfast cereals and cereal bars. This paper presents an assessment of the safety of iron EDTA for its intended uses in these products. Iron EDTA, like other EDTA-metal complexes, dissociates in the gastrointestinal tract to form iron, which is bioavailable, and an EDTA salt; absorption of the metal ion and EDTA are independent. Because of this dissociation, consideration of information on EDTA compounds other than iron EDTA is relevant to this safety assessment. EDTA compounds are poorly absorbed in the gastrointestinal tract and do not undergo significant metabolic conversion. They have a low degree of acute oral toxicity. EDTA compounds are not reproductive or developmental toxicants when fed with a nutrient-sufficient diet or minimal diets supplemented with zinc. In chronic toxicity studies, diets containing as much as 5% EDTA were without adverse effects. EDTA compounds were not carcinogenic in experimental animal bioassays and are not directly genotoxic. This lack of significant toxicity is consistent with a history of safe use of other EDTA compounds (CaNa(2)EDTA and Na(2)EDTA) approved by the FDA for use as direct food additives. An upper-bound estimated daily intake (EDI) of EDTA from iron EDTA (1.15mg/kg bw/day for the US population) is less than half the acceptable daily intake (ADI) for EDTA of 2. 5mg/kg bw/day established by JECFA. The data collected and published over the past 20 to 30 years demonstrate that iron EDTA is safe and effective for iron fortification of food products and meets the standard of "reasonable certainty of no harm". Based on the published record, iron EDTA may be regarded as generally recognized as safe (GRAS) for the intended food uses and maximum use levels.
Assuntos
Compostos Férricos/toxicidade , Alimentos Fortificados , Quelantes de Ferro/toxicidade , Animais , Relação Dose-Resposta a Droga , Ácido Edético/toxicidade , Grão Comestível , Contagem de Eritrócitos , Humanos , Saúde Pública , Segurança , Testes de ToxicidadeRESUMO
BACKGROUND: Breast conservation therapy (BCT) offers equivalent survival to modified radical mastectomy in patients with early-stage (I and IIa) breast cancer, but is utilized in less than 50% of eligible patients. While patient demographics have been linked to BCT rates, we suspected that physician influence was a major factor. The purpose of this study was to compare BCT at three affiliated centers staffed by similarly trained surgeons yet serving widely disparate populations, in order to assess the importance of physician influence on the utilization of BCT. METHODS: Tumor registry data were reviewed from 1993 through 1997 at affiliated city/county (CH), university (UH), and private hospitals (PH). Data were analyzed for clinical stage, treatment, and age of patient. RESULTS: The utilization of BCT for stage I and IIa breast cancer is similar at the three hospitals: 45% of patients at CH, 55% of patient at UH, and 57% of patients at PH (P>0.05). Rates of BCT were similar across all patient age groups at all sites. CONCLUSIONS: Similar BCT utilization rates can be achieved despite widely disparate patient populations. The three affiliated hospitals are staffed by surgeons with similar training, and all offer a multidisciplinary approach to breast cancer care. This suggests that physician influence may override patients' socioeconomic issues in providing optimal breast cancer therapy.
Assuntos
Neoplasias da Mama/cirurgia , Mastectomia Segmentar/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Adulto , Idoso , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Colorado/epidemiologia , Feminino , Hospitais de Condado , Hospitais Privados , Hospitais Universitários , Humanos , Excisão de Linfonodo , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Educação de Pacientes como Assunto , Radioterapia Adjuvante , Fatores SocioeconômicosRESUMO
We investigated whether interleukin-1beta (IL-1beta) is differentially expressed in plasma cells from monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma (MM) patients because IL-1beta appears to play a major role in the development of lytic bone lesions, the major clinical feature distinguishing MGUS from myeloma. In situ hybridization (ISH) for IL-1beta was performed using bone marrow aspirates from 51 MM, 7 smoldering MM, 21 MGUS, and 5 normal control samples. Using the ISH technique IL-1beta mRNA was detectable in the plasma cells from 49 of 51 patients with active myeloma and 7 of 7 patients with smoldering myeloma. In contrast, 5 of 21 patients with MGUS and 0 of 5 normal controls had detectable IL-1beta message. Bone lesions were present in 40 of the 51 MM patients analyzed, and all 40 patients had IL-1beta mRNA by ISH. These results show that greater than 95% of MM patients but less than 25% of MGUS patients are positive for IL-1beta production. In the future, continued follow-up of IL-1beta positive and negative MGUS patients should determine whether aberrant expression of plasma cell IL-1beta is predictive of those MGUS patients that will eventually progress to active myeloma.