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Infections are able to trigger epigenetic modifications; however, epigenetic-mediating infections in the immune system in fish is currently unavailable. Within this purpose, zebrafish were immune-stimulated with three lipopolysaccharides (LPS) during sex differentiation. Methylation patterns of three immune genes were studied by a candidate gene approach together with gene expression analysis, and in adulthood, sex ratios were determined. It was shown that the entrance of LPS was through the gills and accumulated in the pronephros. Significant hypomethylation levels of CASP9 and a significant CpG site for IL1ß after Pseudomonas aeruginosa LPS exposure were found. No methylation difference was observed for TNFα. Gene expression and correlation data differed among studied genes. Sex ratios showed a feminization in dose and LPS strain-dependent manner. Here, it is provided epigenetic regulatory mechanisms derived by innate response and the first evidence of possible epigenetic interactions between the immune and reproductive systems.
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Gônadas/metabolismo , Lipopolissacarídeos/metabolismo , Pseudomonas aeruginosa/metabolismo , Peixe-Zebra/imunologia , Animais , Caspase 9/genética , Caspase 9/metabolismo , Ilhas de CpG/genética , Metilação de DNA , Epigênese Genética , Perfilação da Expressão Gênica , Estudos de Associação Genética , Imunidade , Imunidade Inata , Imunização , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Lipopolissacarídeos/imunologia , Reprodução , Diferenciação Sexual , Razão de Masculinidade , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismoRESUMO
INTRODUCTION: There is sufficient evidence on the usefulness of surgery as a therapeutic alternative for patients with drug-resistant epilepsy; however this treatment is underutilized, especially in developing countries. METHODS: We describe the outcomes of epilepsy surgery in 27 paediatric patients at Hospital Baca Ortiz in Quito, Ecuador. Our analysis considered the following variables: reduction in seizure frequency, surgery outcome according to the Engel classification, improvement in quality of life, and serious complications due to surgery. RESULTS: 21 corpus callosotomies and 6 resective surgeries were performed. The mean seizure frequency decreased from 465 per month before surgery to 37.2 per month thereafter (p<.001); quality of life scale scores increased from 12.6 to 37.2 (p<.001), and quality of life improved in 72.7% of patients. Regarding resective surgery, 2 patients with temporal lobe epilepsy and one with posterior quadrant epilepsy achieved Engel class IA, and one patient undergoing hemispherotomy due to Rasmussen encephalitis achieved Engel class IIA. Two patients underwent surgery for hypothalamic hamartoma: one achieved Engel III and the other, Engel IA; however, the latter patient died in the medium term due to a postoperative complication. The other major complication was a case of hydrocephalus, which led to the death of a patient with refractory infantile spasms who underwent corpus callosotomy. CONCLUSIONS: Favourable outcomes were observed in 92.5% of patients.
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Epilepsia , Criança , Equador , Epilepsia/cirurgia , Feminino , Humanos , Masculino , Qualidade de Vida , Centros de Atenção Terciária , Resultado do TratamentoRESUMO
INTRODUCTION: Posttransplant hepatitis C virus (HCV) recurrence has been shown to negatively impact graft and patient survivals. It has been suggested that HCV recurrence among HIV- and HCV-coinfected transplant recipients is even more aggressive. OBJECTIVE: To compare the histological severity and survival of posttransplant HCV recurrence between HIV- and HCV-coinfected and HCV-monoinfected patients. PATIENTS AND METHODS: Among 72 adult patients who underwent primary liver transplantation at our institution for HCV-related cirrhosis between October 2001 and April 2007. We excluded one coinfected patient who died on postoperative day 5 leaving 12 HIV- and HCV-coinfected patients for comparison with 59 monoinfected patients. When listed, all coinfected patients fulfilled the criteria of the Spanish Consensus Document for transplantation in HIV patients. Immunosuppression did not differ between the two groups: all were treated with tacrolimus + steroids (slow tapering). Aggressive HCV recurrence was defined as cholestatic hepatitis and/or a fibrosis grade > or =2 during the first posttransplant year. RESULTS: Coinfected patients were younger than monoinfected patients: 45 +/- 6 years vs 55 +/- 9 years (P = .0008). There were no differences in Child score, Model for End-stage Liver Disease score, donor age, graft steatosis, ischemia time, HCV pretransplant viral load or genotype between the groups. Significant rejection episodes were also equally distributed (25% vs 14%; P = .38). Seven coinfected patients and 29 monoinfected patients developed aggressive HCV recurrences (58% vs 49%; P = .75). Median follow-up was 924 days. Global survival at 3 years was 80%. Survivals at 1, 2, and 3 years were 83%, 75%, 62% in the coinfected vs 98%, 89%, 84% in the monoinfected patients, respectively (log-rank test = 0.09). CONCLUSIONS: The severity of histological recurrence was similar among HIV- and HCV-coinfected and monoinfected HCV liver recipients in the first posttransplant year. Mortality attributed to recurrent HCV was similar in the groups. There were no short-term (3-year) differences in survival between the two groups of patients.
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Infecções por HIV/complicações , Hepatite C/complicações , Hepatite C/cirurgia , Transplante de Fígado/fisiologia , Corticosteroides/uso terapêutico , Adulto , Biópsia , Quimioterapia Combinada , Feminino , Rejeição de Enxerto/epidemiologia , Hepatite C/mortalidade , Humanos , Imunossupressores/uso terapêutico , Transplante de Fígado/imunologia , Transplante de Fígado/mortalidade , Transplante de Fígado/patologia , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Recidiva , Estudos Retrospectivos , Taxa de Sobrevida , Sobreviventes , Tacrolimo/uso terapêutico , Doadores de Tecidos/estatística & dados numéricos , Carga ViralRESUMO
The reported biliary morbidity rate for deceased donor full-size orthotopic liver transplantation is up to 30%. The technique used may be influenced by multiple factors, and in some situations, biliary reconstruction must be carried out through Roux-en-Y hepaticojejunostomy. The aim of our study was to determine the results of the orthotopic liver transplantation according to the technique used in the biliary reconstruction. A retrospective study was performed with the first 1000 orthotopic liver transplants (951 patients) carried out consecutively (1996-2013) with follow-up until 2017. A matched case-control study was designed in 1:3 ratio (47/136) to compare the reconstruction by hepaticojejunostomy vs the end-to-end coledoco-coledocostomy. Hepaticojejunostomy was associated with patients with cholestatic (44.7% vs 3.7%) and ischemic disease (14.9% vs 0%; P < .001) and previous transplant (29.8% vs 1.5%; P = .003). The mean biliary duct reconstruction, surgery, and cold ischemia times were also higher. Vascular complications were significantly more frequent in the hepaticojejunostomy group (36.1% vs 10.4%; P < .001), mainly because of differences in early arterial complications. Nevertheless, there were no differences in the total biliary complication (21.2% vs 16.9%; P = .5). The biliary leakage rate and the biliary stricture rate were also similar. Hepaticojejunostomy in orthotopic liver transplantation presented longer biliary reconstruction, surgery, and cold ischemia times when compared with end-to-end coledoco-coledocostomy. In addition, it was followed by a higher incidence of arterial complications but had similar biliary complication rate and graft survival. Differences could be explained by the fact that hepaticojejunostomy was used more often in cholestatic or ischemic diseases and in retransplant procedures.
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Anastomose em-Y de Roux/métodos , Procedimentos Cirúrgicos do Sistema Biliar/métodos , Transplante de Fígado/métodos , Procedimentos de Cirurgia Plástica/métodos , Procedimentos Cirúrgicos do Sistema Biliar/efeitos adversos , Estudos de Casos e Controles , Feminino , Vesícula Biliar/cirurgia , Sobrevivência de Enxerto , Humanos , Jejuno/cirurgia , Fígado/cirurgia , Transplante de Fígado/efeitos adversos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Procedimentos de Cirurgia Plástica/efeitos adversos , Estudos RetrospectivosRESUMO
OBJECTIVE: To translate and evaluate the psychometric properties of a quality of life questionnaire specific to liver transplant patients. MATERIAL AND METHODS: The questionnaire was administered to 60 patients on the waiting list for liver transplant in the Cruces Hospital Transplant Unit, and again at 6 months after the transplant. The reliability, validity, sensitivity to change, and minimum detectable change (MDC) were studied. Two questionnaires, the SF-36 (Health Survey Short Form 36) and HADS (Hospital Anxiety and Depression Scale), were used to evaluate the convergent validity. RESULTS: The specific questionnaire presented a Cronbach s alpha coefficient of over 0.7. The factor analysis demonstrates a single dimension. Correlations with the areas of SF-36 varied between -0.34 and -0.71 in the preoperative phase, and between -0.21 and -0.67 at 6 months. With respect to the HAD-anxiety scale, the coefficients were 0.44 in the preoperative phase and 0.51 at 6 months, and for the HAD-depression scale these were 0.64 and 0.39, respectively. Discriminant validation studies confirm that the questionnaire shows differences between patients with cirrhosis of various etiologies and severities. In the study of sensitivity to change, values were obtained for the SES (standardised effect size) and SRM (standardised response mean) indices of 0.92 and 0.99, respectively. Furthermore, 58.33% of patients had scores higher than MDC. CONCLUSIONS: The specific questionnaire has adequate psychometric properties. Its use in these patients may therefore be recommended as another scale for evaluating the results of this intervention.
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Transplante de Fígado , Qualidade de Vida , Inquéritos e Questionários , Feminino , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , PsicometriaRESUMO
Arsenic removal from high-arsenic water in a mine drainage system has been studied through an enhanced coagulation process with ferric ions and coarse calcite (38-74 microm) in this work. The experimental results have shown that arsenic-borne coagulates produced by coagulation with ferric ions alone were very fine, so micro-filtration (membrane as filter medium) was needed to remove the coagulates from water. In the presence of coarse calcite, small arsenic-borne coagulates coated on coarse calcite surfaces, leading the settling rate of the coagulates to considerably increase. The enhanced coagulation followed by conventional filtration (filter paper as filter medium) achieved a very high arsenic removal (over 99%) from high-arsenic water (5mg/l arsenic concentration), producing a cleaned water with the residual arsenic concentration of 13 microg/l. It has been found that the mechanism by which coarse calcite enhanced the coagulation of high-arsenic water might be due to attractive electrical double layer interaction between small arsenic-borne coagulates and calcite particles, which leads to non-existence of a potential energy barrier between the heterogeneous particles.
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Arsênio/isolamento & purificação , Poluentes da Água/isolamento & purificação , Purificação da Água/métodos , Arsênio/química , Carbonato de Cálcio/química , Filtração , Ferro/química , MineraçãoRESUMO
The effect of temperature and pH on the zeta potential of alpha-Al2O3 and adsorption of fluoride ions at the alpha-Al2O3/aqueous solution interface has been investigated through electrophoretic mobility measurements and adsorption studies, to delineate mechanisms involved in the removal of fluoride ions from water using alumina as adsorbent. When the temperature increases from 10 to 40 degrees C, the pH of the point of zero charge (pH(pzc)) shifts to smaller values, indicating proton desorption from the alumina surface. The pH(pzc) increases linearly with 1/T, which allowed estimation of the standard enthalpy change for the surface-deprotonation process. Fluoride ion adsorption follows a Langmuir-type adsorption isotherm and is affected by the electric charge at the alpha-Al2O3/aqueous solution interface and the surface density of hydroxyl groups. Such adsorption occurs through an exchange between fluoride ions and surface-hydroxyl groups and it depends on temperature, pH, and initial fluoride ion concentration. At 25 and 40 degrees C, maximum fluoride adsorption density takes place between pH 5 and 6. Increasing the temperature from 25 to 40 degrees C lowers the adsorption density of fluoride.
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INTRODUCTION: Due to the disparity between the number of patients on the list for liver transplantation and the availability of organs, the use of older donors has become necessary. The aim of this study was to investigate the outcomes of liver transplantation using octogenarian donors. METHODS: From December 2003 to February 2016, 777 liver transplantations were performed at our institution, 33 of them (4.2%) with donors 80 years old and above. Our policy for the acceptance of these donors is based on preoperative liver function tests, donor hemodynamic stability, and intraoperative normal gross aspect. Octogenarian grafts were deliberately not assigned to retransplantations or to recipients with multiple previous surgical procedures or extensive portal thrombosis. RESULTS: Mean donor age was 82.7 ± 2.1 years, with a range between 80 and 88. Only 12.1% suffered hemodynamic instability during the intensive care unit stay. Three donors (9.1%) had a history of diabetes mellitus. The mean Model for End-Stage Liver Disease score among recipients was 14.7 ± 5.6. Mean cold ischemia time was 302 ± 61 minutes. After a median follow-up of 18.5 months (range 7.5 to 47.5), no graft developed primary nonfunction. We observed hepatic artery thrombosis in 1 patient (3%) and biliary complications in 4 patients (12.5%). There was 1 case of ischemic-type biliary lesion, although it was related to hepatic artery thrombosis. Patient survival at 1 and 3 years was 90.3%, whereas graft survival was 92.6% and 86.4%, respectively. CONCLUSIONS: Excellent mid-term results can be obtained after liver transplantation with octogenarian donors with strict donor selection and adequate graft allocation.
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Fatores Etários , Idoso de 80 Anos ou mais/estatística & dados numéricos , Seleção do Doador/métodos , Transplante de Fígado/efeitos adversos , Complicações Pós-Operatórias/etiologia , Doadores de Tecidos/estatística & dados numéricos , Idoso , Isquemia Fria , Feminino , Sobrevivência de Enxerto , Humanos , Transplante de Fígado/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transplantes/fisiopatologia , Transplantes/provisão & distribuição , Resultado do TratamentoRESUMO
OBJECTIVE: The aim of this study was to determine whether a portal flow of <1,000 mL/min in orthotopic liver transplantation (OLT) is associated with a higher incidence of early graft dysfunction (EGD) and graft loss. METHODS: A retrospective study was performed of 540 OLTs carried out consecutively from December 2004 to December 2013. Patients were divided into 2 groups: group A, portal flow <1,000 mL/min; and group B, portal flow >1,000 mL/min. We studied the incidence of EGD and graft survival. A subanalysis was performed to define the minimum acceptable portal flow/100 g of liver weight to reduce the development EGD and graft loss. RESULTS: Group A included 29 patients and group B, 511 patients. Group A had significantly lower-weight donors and recipients, female recipients with cholestatic disease, lower MELD scores, and lower hepatic artery flow. EGD occurred in 7 patients in group A (24.1%) versus 101 patients in group B (19.8%; P = .43). No significant differences were found in 1- and 5-year graft survival. A portal flow of <80 mL/min/100 g of liver weight was related to a significantly higher risk of developing EGD (odds ratio, 4.35; 95% confidence interval [CI], 1.46-12.91; P = .008) and graft loss (hazard ratio, 4.05; 95% CI, 1.32-12.42; P = .014). CONCLUSIONS: Intraoperative portal flow of <1,000 mL/min in OLT was not related per se with a higher incidence of EGD or graft loss. Significantly higher risk of developing EGD and graft loss was associated with a portal flow of <80 mL/min/100 g of liver weight.
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Circulação Hepática , Transplante de Fígado , Fígado/irrigação sanguínea , Disfunção Primária do Enxerto/epidemiologia , Adulto , Feminino , Sobrevivência de Enxerto , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Razão de Chances , Estudos RetrospectivosRESUMO
INTRODUCTION: Expansion of donor criteria has become necessary with the increasing number of liver transplantation candidates, as aged donors who have been considered to yield marginal organs. METHODS: Our database of 477 liver transplants (OLT) included 55 cases performed from donors at least 70 years old vs 422 with younger donors. We analyzed pretransplantation donor and recipient characteristics as well as evolution of the recipients. RESULTS: The old donor group showed significantly lower ALT (23 +/- 17 vs 48.9 +/- 67; P = .0001) and LDH (444 +/- 285 vs 570 +/- 329; P = .01). There was a trend toward fewer hypotensive events in the aged donor group (27.2% vs 40.5%; P = .07). No steatosis (>10%) was accepted in the old donor group. Cold ischemia time was statistically shorter for the aged donors (297 +/- 90 minutes vs 346 +/- 139 minutes; P = .03). With these selected donors, the results were not different for primary nonfunction, arterial and biliary complications, hospitalization, acute reoperation or acute retransplantation, and hospital mortality when donors > or =70 years old were compared to younger donors. Functional cholestasis, neither related to rejection nor to biliary complications, was seen more frequently in old donor recipients (40% vs 22%; P = .03). No differences in 1, and 3 year survivals were observed between recipients of donors over 70 years old and these of younger organs: 93.8% and 90.6% vs 90.7% and 82.8%, respectively. CONCLUSION: When using selected donors > or =70 years old the outcomes were comparable to those obtained with younger donors. Strict selection is necessary to achieve good long-term survival.
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Testes de Função Hepática , Transplante de Fígado/fisiologia , Fígado , Doadores de Tecidos/estatística & dados numéricos , Fatores Etários , Idoso , Causas de Morte , Feminino , Sobrevivência de Enxerto , Humanos , Transplante de Fígado/mortalidade , Masculino , Reoperação , Análise de Sobrevida , Resultado do TratamentoRESUMO
Studies on the Merrill-Crowe process as applied to silver recovery have shown that one half of the used zinc powder is wasted in water reduction at high cyanide concentrations, while the other half reduces silver ions from the cyanide solution. However, the cementation mechanisms as an electrochemical process taking place on the zinc surface do not explain the split of the electric current resulting from the anodic dissolution of zinc into two equal values. This study demonstrates that the mechanism for silver precipitation at high and low cyanide concentrations differs considerably. At low cyanide concentrations cementation is essentially an electrochemically-controlled process following a shrinking-core behavior. At high cyanide concentrations, the process seems not to be electrochemically controlled. The areas for zinc dissolution and silver deposition are not connected by an electrical-conducting medium and reduction of silver-cyano complex ions takes place by hydrogen adsorbed onto silver growing outward from the cementing zinc particles. The results are based on scanning electron microscopy of solids recovered from cementations in stirred reactors and in situ observations by optical microscopy of the cementation process on the edge of thin zinc disks in cyanide solutions.
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Biofísica/métodos , Zinco/química , Adsorção , Corantes , Cobre/química , Cianetos/química , Relação Dose-Resposta a Droga , Condutividade Elétrica , Impedância Elétrica , Eletroquímica , Hidrogênio , Íons , Modelos Químicos , Prata/química , Compostos de ZincoRESUMO
On the basis of the Einstein theory of viscosity of dispersion, a parameter, termed as solvation factor, is presented to evaluate the solvation degree of nanoscale particles dispersed in a liquid in this work. The value of the parameter is obtained through the measurements of relative viscosity of the dispersions as a function of the volume fraction of dry particles. The solvation factor has been used to study the hydration layers near nanoscale silica particles dispersed in water and aqueous electrolyte (NaCl and CaCl2) solutions in this work. The experimental results have shown that a strong hydration indeed applied to the silica surfaces in aqueous solutions, leaving a large volume of hydration layers on the surfaces. Also, it has been found that the hydration of the nanoscale silica particles could be greatly enhanced if they were dispersed in aqueous NaCl or CaCl2 solutions, which might be attributed to that the hydrated cations (Na+ or Ca2+) bind onto the silica/ water interface and thus increase the volume of the hydration layers.
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OBJECTIVE: The main objective is to evaluate the complications and problems encountered in a population with inner ear congenital malformation undergoing cochlear implantation. MATERIALS AND METHODS: The present study includes 33 patients with congenital inner ear malformation, from a total population of 346 cochlear implant patients, implanted from February 1993 to March 2004. Radiological evaluation and neurological exams were performed to all these patients in order to evaluate all the preoperative conditions. RESULTS: The most common cochlear anomalies we found were: cochlear hypoplasia, Incomplete partition and Common cavity (n=15). In 4 cases an enlarge aqueduct was also associated to the cochlear anomaly. We also found 6 cases with labyrinthine anomalies. The surgical procedure was performed in 23 cases, and in 18 of them we obtained an electrical stimulation of the neural elements. CONCLUSIONS: There are no differences between patients with Incomplete Partition of the cochlea and mild Cochlea hypoplasia, if compared with those with normal cochlea. Severe malformations as Common Cavity or severe hypoplasia may have a higher rate of surgical complications and the outcome cannot be predicted.
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Implantes Cocleares , Orelha Interna/anormalidades , Orelha Interna/cirurgia , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Complicações Pós-Operatórias/epidemiologiaRESUMO
A consecutive series of 88 patients underwent transplantation for hepatocellular carcinoma with cirrhosis over a 7-year period. Liver transplantation was indicated because of the tumor in 75 cases (85.2%); tumor was an incidental finding in 13 cases (14.8%). One patient was retransplanted due to primary nonfunction. The perioperative mortality was 4.5%. Tumor recurrence was observed in seven patients (7.95%) with incidental tumor recurrence in one case. As in patients with known primary liver tumors pretransplant, a thorough follow-up is advisable to establish an early diagnosis of recurrence. The actuarial survival for nonincidental hepatocellular carcinoma at 1, 3, and 5 year was 92%, 77%, and 75%, respectively. The differences in actuarial survival between hepatitis C negative and positive hepatocellular carcinoma were not significant (log-rank test P=.27), though there was a clear improvement in results (94%, 85%, and 78% vs 90%, 71%, and 71%), at 1, 3, and 5 years meaning that HCV infection is an important prognostic factor. Although transplantation for HCC has the advantages of removing the tumor and the cirrhotic liver, it remains a controversial topic. In our experience patients showing lesions less than 5 cm or three or fewer lesions experience an equivalent survival to transplanted patients who do not have cancer.
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Carcinoma Hepatocelular/cirurgia , Cirrose Hepática/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/estatística & dados numéricos , Adulto , Idoso , Causas de Morte , Feminino , Humanos , Imunossupressores/uso terapêutico , Tempo de Internação , Transplante de Fígado/imunologia , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Recidiva , Estudos Retrospectivos , Análise de Sobrevida , Fatores de TempoRESUMO
INTRODUCTION: Palliative treatment for nondisseminated irresectable hilar cholangiocarcinoma (HCC) carries a 0% 5-year survival rate. The role of orthotopic liver transplantation (OLT) in these patients is controversial because the survival rate is lower than that for other indications for transplantation and the lack of available donor organs. The aim of this paper was to review the Spanish experience in OLT for HCC and identify prognostic factors for survival. METHODS: We retrospectively reviewed 36 patients undergoing OLT for HCC over 13 years. RESULTS: The actuarial survival rate at 1, 3, and 5 years was 82%, 53%, and 30%, respectively. The main cause of death was tumor recurrence (53%). In the univariate analysis, the factors for a poor prognosis were vascular invasion (P<.001) namely 0% survival at 3 years when present versus 63% and 35% at 3 and 5 years, respectively, when it was not; and stages III to IVA (P<.05), namely 15% survival at 5 years versus 47% for stages I to II. Lymph node and perineural invasion also reduce survival. In the multivariate analysis, the factors for poor prognosis included vascular invasion (P<.01) and stages III to IVA (P<.01). CONCLUSION: OLT for nondisseminated irresectable HCC has higher survival rates at 3 and 5 years than palliative treatments, especially with initial stage tumors, which means that more information is needed to better select cholangiocarcinoma patients for transplantation.
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Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/cirurgia , Transplante de Fígado/mortalidade , Seguimentos , Humanos , Estadiamento de Neoplasias , Cuidados Paliativos , Estudos Retrospectivos , Análise de Sobrevida , Fatores de TempoRESUMO
INTRODUCTION: Palliative treatment for nondisseminated unresectable peripheral cholangiocarcinoma (PCC) carries a 0% 5-year survival rate. The role of orthotopic liver transplantation (OLT) in these patients is controversial because the survival rate is lower than with other indications for transplantation and the lack of available donor organs. The aim of this paper was to review the Spanish experience in OLT for PCC to identify prognostic factors for survival. METHODS: We retrospectively reviewed 23 patients undergoing OLT in Spain for PCC over a period of 13 years. RESULTS: The actuarial survival rates were 77%, 65%, and 42% at 1, 3, and 5 years, respectively. The main cause of death was tumor recurrence (35%). Prognotic factors for an adverse outcome were pTNM classification (P<.05) in the univariate analysis and perineural invasion (P<.05) and stages III or IVA (P<.05) in the multivariate analysis. CONCLUSIONS: OLT for nondisseminated irresectable PCC displays higher survival rates at 3 and 5 years than palliative treatments, especially for tumors in the initial stages, which means that more information is needed to help better select PCC patients for transplantation.
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Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/cirurgia , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/mortalidade , Colangiocarcinoma/patologia , Seguimentos , Humanos , Transplante de Fígado , Metástase Neoplásica , Cuidados Paliativos , Recidiva , Estudos Retrospectivos , Análise de Sobrevida , Fatores de TempoRESUMO
The most important factor in the electrodialysis (ED) process is the permselectivity of the ion exchange membranes, which permit not only the separation of cations and anions in a solution, but also the separation of ions with the same sign but different valences. In this work, the mechanism of the permselectivity has been studied through the measurement of the potentials at different planes of the membrane. The experimental results have shown that there was a secondary potential inside ion exchange membranes in an electrodialysis process. At the membrane side touched with dilute solution, this secondary potential enhanced the external electrical field, and thus speeded up the passage of the corresponding ions in the dilute solution through the membranes; at the membrane side touched with concentrated solution, the secondary potential was contrary to the external electrical field and thus counteracted it, which could be very helpful by preventing the ions in the concentrated solution from entering the membranes. Obviously, the existence of the secondary potential might play an important role in the permselectivity of ion exchange membranes in ED processes.
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In a previous study we have observed that NH4Cl-induced metabolic acidosis halted the progression of renal disease in azotemic rats with a high phosphate diet. We hypothesized that NH4Cl-induced metabolic acidosis may exert its protective effect by decreasing renal calcium content independent of serum levels of PTH and phosphate loading. To test this hypothesis we studied azotemic rats with very low phosphate diet or parathyroidectomy. Rats with low phosphate diet and parathyroidectomized rats developed renal failure after 5/6 nephrectomy, and in both groups the acid loading significantly decreased the progression of renal disease. Calcium renal content increased in both groups, even in rats with low phosphate diet, and this effect was also significantly decreased after an acid loading. Rats with acid loading developed greater hypertrophy of renal tissue than rats without acid loading. We conclude that NH4Cl-induced metabolic acidosis halted the progression of renal disease by decreasing calcium precipitation on renal tissue. Parathyroidectomy did not prevent progression of renal disease nor calcium precipitation, and a low phosphate diet in azotemic rats did not prevent increased calcium content on remnant renal tissue.