Study of laser fluorescence spectroscopy in livers of rats with hypothermic ischemia.

PURPOSE: After partial hepatectomy (PH), the remaining liver (RL) undergoes regenerative response proportional to the host. Limited literature exists on hepatic viability after tissue injury during hypothermic preservation. Spectroscopy measures cellular fluorescence and is explored for tissue characterization and parameter investigation. This study aimed to assess fluorescence analysis (spectroscopy) in evaluating liver viability and its relationship with hepatic tissue regeneration 24 hours after PH. Additionally, we analyzed liver regeneration in RL after 70% partial hepatectomy under hypothermic conditions with laser irradiation. METHODS: Fifty-six Wistar rats were divided into four groups: total non-perfused liver (control), total perfused liver, partial hepatectomy "in situ", and partial hepatectomy "ex situ". Tissue analysis was performed at 0 and 24 hours using spectroscopy with laser devices emitting at 532 (green) and 405 nm (violet). RESULTS: Spectroscopy identified tissue viability based on consistent results with Ki67 staining. The fluorescence spectra and Ki67 analysis displayed similar patterns, linking proliferative activity and absorption intensity. CONCLUSIONS: Fluorescence spectroscopy proves to be promising for real-time analysis of cellular activity and viability. Metabolic activity was observed in groups of live animals and hypothermically preserved samples, indicating cellular function even under blood deprivation and hypothermic conditions.

THE OPTIMUM LEVEL OF MELD TO MINIMIZE THE MORTALITY ON LIVER TRANSPLANTATION WAITING LIST, AND LIVER TRANSPLANTED PATIENT IN SÃO PAULO STATE, BRAZIL.

BACKGROUND: After validation in multiple types of liver disease patients, the MELD score was adopted as a standard by which liver transplant candidates with end-stage liver disease were prioritized for organ allocation in the United States since 2002, and in Brazil, since 2006. AIMS: To analyze the mortality profile of patients on the liver transplant waiting list correlated to MELD score at the moment of transplantation. METHODS: This study used the data from the Secretary of Health of the São Paulo State, Brazil, which listed 22,522 patients, from 2006 (when MELD score was introduced in Brazil) until June 2009. Patients with acute hepatic failure and tumors were included as well. We also considered the mortality of both non-transplanted and transplanted patients as a function of the MELD score at presentation. RESULTS: Our model showed that the best MELD score for patients on the liver transplant waiting list associated to better results after liver transplantation was 26. CONCLUSIONS: We found that the best score for applying to liver transplant waiting list in the State of São Paulo was 26. This is the score that minimizes the mortality in both non-transplanted and liver transplanted patients.

Multivisceral transplantation of pelvic organs in rats.

Background: Multivisceral transplantation of pelvic organs would be a potential treatment for severe pelvic floor dysfunction with fecal and urinary incontinence, extensive perineal trauma, or congenital disorders. Here, we describe the microsurgical technique of multivisceral transplantation of pelvic organs, including the pelvic floor, in rats. Donor operation: We performed a perineal (including the genitalia, anus, muscles, and ligaments) and abdominal incision. The dissection progressed near the pelvic ring, dividing ligaments, muscles, external iliac vessels, and pudendal nerves, allowing pelvic floor mobilization. The aorta and vena cava were isolated distally, preserving the internal iliac and gonadal vessels. The graft containing the skin, muscles, ligaments, bladder, ureter, rectum, anus and vagina, uterus and ovarian (female), or penile, testis and its ducts (male) was removed en bloc, flushed, and cold-stored. Recipient operation: The infrarenal aorta and vena cava were isolated and donor/recipient aorta-aorta and cava-cava end-to-side microanastomoses were performed. After pelvic floor and viscera removal, we performed microanastomoses between the donor and the recipient ureter, and the rectum and pudenda nerves. The pelvic floor was repositioned in its original position (orthotopic model) or the abdominal wall (heterotopic model). We sacrificed the animals 2 h after surgery. Results: We performed seven orthotopic and four heterotopic transplantations. One animal from the orthotopic model and one from the heterotopic model died because of technical failure. Six orthotopic and three heterotopic recipients survived up to 2 h after transplantation. Conclusion: The microsurgical technique for pelvic floor transplantation in rats is feasible, achieving an early survival rate of 81.82%.

The optimum level of meld to minimize the mortality on liver transplantation waiting list, and liver transplanted patient in são paulo state, brazil / Melhor nível do meld para minimizar a mortalidade em lista de transplante de fígado no estado de são paulo, brasil

ABSTRACT BACKGROUND: After validation in multiple types of liver disease patients, the MELD score was adopted as a standard by which liver transplant candidates with end-stage liver disease were prioritized for organ allocation in the United States since 2002, and in Brazil, since 2006. AIMS: To analyze the mortality profile of patients on the liver transplant waiting list correlated to MELD score at the moment of transplantation. METHODS: This study used the data from the Secretary of Health of the São Paulo State, Brazil, which listed 22,522 patients, from 2006 (when MELD score was introduced in Brazil) until June 2009. Patients with acute hepatic failure and tumors were included as well. We also considered the mortality of both non-transplanted and transplanted patients as a function of the MELD score at presentation. RESULTS: Our model showed that the best MELD score for patients on the liver transplant waiting list associated to better results after liver transplantation was 26. CONCLUSIONS: We found that the best score for applying to liver transplant waiting list in the State of São Paulo was 26. This is the score that minimizes the mortality in both non-transplanted and liver transplanted patients.

RESUMO RACIONAL: Desde 2002, após validação em múltiplos tipos de hepatopatias, o escore MELD foi adotado como padrão pelo qual os candidatos a transplante de fígado com doença hepática terminal têm sido priorizados para alocação de órgãos nos Estados Unidos, e em 2006 no Brasil. OBJETIVOS: Analisar a mortalidade de pacientes em lista de espera para transplante de fígado correlacionando com o MELD, no momento do transplante. MÉTODOS: Foram utilizados os dados da Secretaria de Saúde do Estado de São Paulo, Brasil, onde foram listados 22.522 pacientes, desde 2006 (quando o escore MELD foi introduzido no Brasil) até junho de 2009. Foram incluídos pacientes com falência hepática e tumores. A mortalidade de pacientes não transplantados e transplantados também foi considerada em função do escore MELD. RESULTADOS: Nosso modelo mostrou que o melhor valor do MELD, em pacientes em lista de espera para transplante e com melhores resultados, foi de 26. Este valor minimiza mortalidade em pacientes não transplantados bem comem pacientes na lista de espera para transplante de fígado. CONCLUSÕES: O escore MELD ótimo para entrar na lista de espera para transplante de fígado, no estado de São Paulo, é em torno de 26. Esse é o valor que minimiza a mortalidade tanto dos pacientes não transplantados em lista de espera, quanto dos submetidos à transplante de fígado.

Study of laser fluorescence spectroscopy in livers of rats with hypothermic ischemia

Purpose: After partial hepatectomy (PH), the remaining liver (RL) undergoes regenerative response proportional to the host. Limited literature exists on hepatic viability after tissue injury during hypothermic preservation. Spectroscopy measures cellular fluorescence and is explored for tissue characterization and parameter investigation. This study aimed to assess fluorescence analysis (spectroscopy) in evaluating liver viability and its relationship with hepatic tissue regeneration 24 hours after PH. Additionally, we analyzed liver regeneration in RL after 70% partial hepatectomy under hypothermic conditions with laser irradiation. Methods: Fifty-six Wistar rats were divided into four groups: total non-perfused liver (control), total perfused liver, partial hepatectomy "in situ", and partial hepatectomy "ex situ". Tissue analysis was performed at 0 and 24 hours using spectroscopy with laser devices emitting at 532 (green) and 405 nm (violet). Results: Spectroscopy identified tissue viability based on consistent results with Ki67 staining. The fluorescence spectra and Ki67 analysis displayed similar patterns, linking proliferative activity and absorption intensity. Conclusions: Fluorescence spectroscopy proves to be promising for real-time analysis of cellular activity and viability. Metabolic activity was observed in groups of live animals and hypothermically preserved samples, indicating cellular function even under blood deprivation and hypothermic conditions.

THE M-RNA, EXPRESSION OF SERCA2 AND NCX1 IN THE PROCESS OF PHARMACOLOGICAL CELL PROTECTION IN EXPERIMENTAL ACUTE PANCREATITIS INDUCED BY TAUROCHOLATE.

BACKGROUND: Intracellular calcium overload is known to be a precipitating factor of pancreatic cell injury in acute pancreatitis (AP). Intracellular calcium homeostasis depends of Plasmatic Membrane Calcium ATPase (PMCA), Sarcoplasmic Endothelial Reticulum Calcium ATPase 2 (SERCA 2) and the Sodium Calcium Exchanger (NCX1). The antioxidant melatonin (Mel) and Trisulfate Disaccharide (TD) that accelerates NCX1 action could reduce the cell damage determined by the AP. AIM: To evaluate m-RNA expressions of SERCA2 and NCX1 in acute pancreatitis induced by sodium taurocholate in Wistar rats pre-treated with melatonin and/or TD. METHODS: Wistar rats were divided in groups: 1) without AP; 2) AP without pre-treatment; 3) AP and Melatonin; 4) AP and TD; 5) AP and Melatonin associated to TD. Pancreatic tissue samples were collected for detection of SERCA2 and NCX1 m-R NA levels by polymerase chain reaction (PCR). RESULTS: Increased m-RNA expression of SERCA2 in the melatonin treated group, without increase of m-RNA expression of the NCX1. The TD did not affect levels of SERCA2 and NCX1 m-RNA expressions. The combined melatonin and TD treatment reduced the m-RNA expression of SERCA2. CONCLUSIONS: The effect of melatonin is restricted to increased m-RNA expression of SERCA2. Although TD does not affect gene expression, its action in accelerating calcium exchanger function can explain the slightest expression of SERCA2 m-RNA when associated with Melatonin, perhaps by a joint action of drugs with different and but possibly complementary mechanisms.

Gastric fundus submucosa as a site for islets transplantation: An experimental study.

BACKGROUND: Islets of Langerhans transplantation is a promising alternative for glycemic control in patients with type 1 diabetes. The graft site is a factor that has large impact on the functioning of this transplant, and the stomach appears to be a promising location. Our objective is to describe a new experimental model for the grafting of Islets of Langerhans in rat stomachs. METHODOLOGY: Islets of Langerhans were extracted from 45 isogenic male rats of the Lewis lineage and transplanted into 9 isogenic rats of the Wistar lineage; 5 in the gastric body submucosa, and 4 in the gastric fundus submucosa. Normoglycemia was defined as two successive measurements of <250 mg/dL. No immunosuppression was used. The two groups glycemia control improvement were compared with t-student test. RESULTS: The results obtained following the transplantation of the islets in 9 rats showed between 995 and 2310 islets transplanted (mean of 1367). The rats from the gastric submucosa group had a better glycemic level improvement, with a confidence equal to 83.94%. CONCLUSION: Islets graft into the gastric fundus submucosa is a viable model with potential for adequate glycemic control. This model gives potential for new perspectives and future studies in this area.

The m-rna, expression of serca2 and ncx1 in the process of pharmacological cell protection in experimental acute pancreatitis induced by taurocholate / Expressão do rna-m, da serca2 e do ncx1 no processo de proteção celular farmacológica na pancreatite aguda experimental induzida por taurocolato

ABSTRACT Background: Intracellular calcium overload is known to be a precipitating factor of pancreatic cell injury in acute pancreatitis (AP). Intracellular calcium homeostasis depends of Plasmatic Membrane Calcium ATPase (PMCA), Sarcoplasmic Endothelial Reticulum Calcium ATPase 2 (SERCA 2) and the Sodium Calcium Exchanger (NCX1). The antioxidant melatonin (Mel) and Trisulfate Disaccharide (TD) that accelerates NCX1 action could reduce the cell damage determined by the AP. Aim: To evaluate m-RNA expressions of SERCA2 and NCX1 in acute pancreatitis induced by sodium taurocholate in Wistar rats pre-treated with melatonin and/or TD. Methods: Wistar rats were divided in groups: 1) without AP; 2) AP without pre-treatment; 3) AP and Melatonin; 4) AP and TD; 5) AP and Melatonin associated to TD. Pancreatic tissue samples were collected for detection of SERCA2 and NCX1 m-R NA levels by polymerase chain reaction (PCR). Results: Increased m-RNA expression of SERCA2 in the melatonin treated group, without increase of m-RNA expression of the NCX1. The TD did not affect levels of SERCA2 and NCX1 m-RNA expressions. The combined melatonin and TD treatment reduced the m-RNA expression of SERCA2. Conclusions: The effect of melatonin is restricted to increased m-RNA expression of SERCA2. Although TD does not affect gene expression, its action in accelerating calcium exchanger function can explain the slightest expression of SERCA2 m-RNA when associated with Melatonin, perhaps by a joint action of drugs with different and but possibly complementary mechanisms.

RESUMO Racional: A lesão celular da pancreatite aguda (PA) envolve sobrecarga de cálcio, regulada pela atividade da Cálcio ATPase de membrana (PMCA), Cálcio ATPase do Retículo (SERCA2) e pelo Trocador Sódio Cálcio (NCX1). A melatonina (antioxidante) e o Dissacarídeo Trissulfatado (acelerador do NCX1) poderiam reduzir a lesão celular na PA. Objetivo: Avaliar a expressão do RNAm da SERCA2 e NCX1 em modelo animal de pancreatite aguda tratados com melatonina e/ou dissacarídeo trissulfatado (DT). Método: Ratos Wistar foram divididos em grupos: 1) sem pancreatite aguda; 2) com pancreatite aguda por taurocolato; 3) PA e Melatonina; 4) PA e DT; 5) PA e Melatonina com DT. Amostras de tecido foram colhidas para detecção dos níveis de RNAm da SERCA2 e NCX1 por PCR. Resultados: Houve aumento da expressão do RNAm da SERCA2 no grupo com PA tratados com Melatonina, porém sem aumento de expressão do NCX1. O DT não afetou os níveis de SERCA2 e NCX1. O tratamento conjunto com Melatonina e DT diminuiu a expressão da SERCA2. Conclusões: O efeito da Melatonina é restrito ao aumento da expressão da SERCA2. O DT não tem ação na expressão gênica, porém sua ação na aceleração do trocador na retirada do cálcio pode explicar a menor expressão da SERCA2 quando associado à Melatonina, pela ação conjunta de drogas com mecanismos diferentes e possivelmente complementares.

Estimating the prevalence of infectious diseases from under-reported age-dependent compulsorily notification databases.

BACKGROUND: National or local laws, norms or regulations (sometimes and in some countries) require medical providers to report notifiable diseases to public health authorities. Reporting, however, is almost always incomplete. This is due to a variety of reasons, ranging from not recognizing the diseased to failures in the technical or administrative steps leading to the final official register in the disease notification system. The reported fraction varies from 9 to 99% and is strongly associated with the disease being reported. METHODS: In this paper we propose a method to approximately estimate the full prevalence (and any other variable or parameter related to transmission intensity) of infectious diseases. The model assumes incomplete notification of incidence and allows the estimation of the non-notified number of infections and it is illustrated by the case of hepatitis C in Brazil. The method has the advantage that it can be corrected iteratively by comparing its findings with empirical results. RESULTS: The application of the model for the case of hepatitis C in Brazil resulted in a prevalence of notified cases that varied between 163,902 and 169,382 cases; a prevalence of non-notified cases that varied between 1,433,638 and 1,446,771; and a total prevalence of infections that varied between 1,597,540 and 1,616,153 cases. CONCLUSIONS: We conclude that the model proposed can be useful for estimation of the actual magnitude of endemic states of infectious diseases, particularly for those where the number of notified cases is only the tip of the iceberg. In addition, the method can be applied to other situations, such as the well-known underreported incidence of criminality (for example rape), among others.

PRELIMINARY RESULTS OF TOPICAL HEPATIC HYPOTHERMIA IN A MODEL OF LIVER ISCHEMIA/REPERFUSION INJURY IN RATS.

BACKGROUND: Ischemia/reperfusion causes organ damage but it is mandatory in hepatic transplantation, trauma and other complex liver surgeries, when Pringle maneuver is applied to minimize bleeding during these procedures. It is well known that liver ischemia/reperfusion leads to microcirculatory disturbance and cellular injury. In this setting hypothermia is known to reduce oxygen demand, lowering intracellular metabolism. OBJECTIVE:: To evaluate the effects of hypothermia in liver ischemia/reperfusion injury, using a new model of topic isolated liver hypothermia. METHODS: We used male Wistar rats weighting about 250 grams, kept in ad libitum feeding regime and randomly divided into two groups of nine animals: 1) Normothermic group, rats were submitted to normothermic ischemia of the median and left hepatic lobes, with subsequent resection of right and caudate lobes during liver reperfusion; and 2) Hypothermic group, rats were submitted to liver ischemia under hypothermia at 10°C. Liver ischemia was performed for 45 minutes. The animals were euthanized 48 hours after liver reperfusion for blood and liver tissue sampling. RESULTS: The transaminases analyses showed a significant decrease of AST and ALT in Hypothermic group (P<0.01) compared to Normothermic group (1403±1234 x 454±213 and 730±680 x 271±211 U/L, respectively). Histology showed severe necrosis in 50% and mild necrosis in 50% of cases in Normothermic group, but severe necrosis in 10% and mild or absent necrosis 90% of the cases in hypothermic group. CONCLUSION:: A simplified model of liver ischemia/reperfusion that simulates orthotopic liver autotransplantion was demonstrated. Topical hypothermia of isolated hepatic lobules showed liver protection, being a viable and practical method for any kind of in vivo liver preservation study.

Resultados preliminares de hipotermia tópica do fígado em modelo de isquemia/reperfusão hepática em ratos / Preliminary results of topical hepatic hypothermia in a model of liver ischemia/reperfusion injury in rats

ABSTRACT BACKGROUND Ischemia/reperfusion causes organ damage but it is mandatory in hepatic transplantation, trauma and other complex liver surgeries, when Pringle maneuver is applied to minimize bleeding during these procedures. It is well known that liver ischemia/reperfusion leads to microcirculatory disturbance and cellular injury. In this setting hypothermia is known to reduce oxygen demand, lowering intracellular metabolism. OBJECTIVE: To evaluate the effects of hypothermia in liver ischemia/reperfusion injury, using a new model of topic isolated liver hypothermia. METHODS We used male Wistar rats weighting about 250 grams, kept in ad libitum feeding regime and randomly divided into two groups of nine animals: 1) Normothermic group, rats were submitted to normothermic ischemia of the median and left hepatic lobes, with subsequent resection of right and caudate lobes during liver reperfusion; and 2) Hypothermic group, rats were submitted to liver ischemia under hypothermia at 10°C. Liver ischemia was performed for 45 minutes. The animals were euthanized 48 hours after liver reperfusion for blood and liver tissue sampling. RESULTS The transaminases analyses showed a significant decrease of AST and ALT in Hypothermic group (P<0.01) compared to Normothermic group (1403±1234 x 454±213 and 730±680 x 271±211 U/L, respectively). Histology showed severe necrosis in 50% and mild necrosis in 50% of cases in Normothermic group, but severe necrosis in 10% and mild or absent necrosis 90% of the cases in hypothermic group. CONCLUSION: A simplified model of liver ischemia/reperfusion that simulates orthotopic liver autotransplantion was demonstrated. Topical hypothermia of isolated hepatic lobules showed liver protection, being a viable and practical method for any kind of in vivo liver preservation study.

RESUMO CONTEXTO: A isquemia/reperfusão leva a grave lesão de órgãos, mas ocorre obrigatoriamente no transplante hepático, no trauma e em outras cirurgias hepáticas complexas, quando a manobra de Pringle é aplicada com o intuito de minimizar o sangramento durante os procedimentos. É bem conhecido que a isquemia/reperfusão do fígado leva a distúrbios microcirculatórios e lesões celulares. Neste cenário, a hipotermia é conhecida por reduzir a demanda de oxigênio, diminuindo o metabolismo intracelular. OBJETIVO: Avaliar os efeitos da hipotermia na lesão de isquemia/reperfusão hepática utilizando-se um novo modelo de hipotermia isolada do fígado. MÉTODOS: Utilizaram-se ratos Wistar do sexo masculino com peso aproximado de 250 gramas, mantidos em regime de alimentação ad libitum e divididos aleatoriamente em dois grupos de nove animais: 1) Grupo Normotérmico - os ratos foram submetidos a isquemia normotérmica dos lobos hepáticos mediano e esquerdo, com posterior ressecção dos lobos direito e caudado durante a reperfusão hepática; e 2) Grupo Hipotérmico - os ratos foram submetidos a isquemia hepática sob hipotermia a 10°C. A isquemia hepática foi realizada durante 45 minutos. Os animais foram sacrificados 48 horas após a reperfusão hepática para coleta de sangue e tecido hepático para análise. RESULTADOS: As transaminases AST e ALT apresentaram diminuição significativa no grupo Hipotérmico (P<0,01) em relação ao grupo Normotérmico (1403±1234 x 454±213 e 730±680 x 271±211 U/L, respectivamente). A histologia mostrou necrose grave em 50% e necrose leve em 50% dos casos no grupo Normotérmico, porém, necrose grave em 10% e necrose leve ou ausente em 90% dos casos no grupo Hipotérmico. CONCLUSÃO: Foi demonstrado modelo simplificado de isquemia/reperfusão do fígado que simula o autotrasplante de fígado. A hipotermia tópica dos lóbulos hepáticos isolados mostrou proteção do fígado a ischemia/reperfusão, sendo um método viável e prático para qualquer tipo de estudo de preservação hepática in vivo.

Human islet xenotransplantation in rodents: A literature review of experimental model trends.

Among the innovations for the treatment of type 1 diabetes, islet transplantation is a less invasive method of treatment, although it is still in development. One of the greatest barriers to this technique is the low number of pancreas donors and the low number of pancreases that are available for transplantation. Rodent models have been chosen in most studies of islet rejection and type 1 diabetes prevention to evaluate the quality and function of isolated human islets and to identify alternative solutions to the problem of islet scarcity. The purpose of this study is to conduct a review of islet xenotransplantation experiments from humans to rodents, to organize and analyze the parameters of these experiments, to describe trends in experimental modeling and to assess the viability of this procedure. In this study, we reviewed recently published research regarding islet xenotransplantation from humans to rodents, and we summarized the findings and organized the relevant data. The included studies were recent reports that involved xenotransplantation using human islets in a rodent model. We excluded the studies that related to isotransplantation, autotransplantation and allotransplantation. A total of 34 studies that related to xenotransplantation were selected for review based on their relevance and current data. Advances in the use of different graft sites may overcome autoimmunity and rejection after transplantation, which may solve the problem of the scarcity of islet donors in patients with type 1 diabetes.

Human islet xenotransplantation in rodents: A literature review of experimental model trends

Among the innovations for the treatment of type 1 diabetes, islet transplantation is a less invasive method of treatment, although it is still in development. One of the greatest barriers to this technique is the low number of pancreas donors and the low number of pancreases that are available for transplantation. Rodent models have been chosen in most studies of islet rejection and type 1 diabetes prevention to evaluate the quality and function of isolated human islets and to identify alternative solutions to the problem of islet scarcity. The purpose of this study is to conduct a review of islet xenotransplantation experiments from humans to rodents, to organize and analyze the parameters of these experiments, to describe trends in experimental modeling and to assess the viability of this procedure. In this study, we reviewed recently published research regarding islet xenotransplantation from humans to rodents, and we summarized the findings and organized the relevant data. The included studies were recent reports that involved xenotransplantation using human islets in a rodent model. We excluded the studies that related to isotransplantation, autotransplantation and allotransplantation. A total of 34 studies that related to xenotransplantation were selected for review based on their relevance and current data. Advances in the use of different graft sites may overcome autoimmunity and rejection after transplantation, which may solve the problem of the scarcity of islet donors in patients with type 1 diabetes.

Allogeneic anorectal transplantation in rats: technical considerations and preliminary results.

Fecal incontinence is a challenging condition with numerous available treatment modalities. Success rates vary across these modalities, and permanent colostomy is often indicated when they fail. For these cases, a novel potential therapeutic strategy is anorectal transplantation (ATx). We performed four isogeneic (Lewis-to-Lewis) and seven allogeneic (Wistar-to-Lewis) ATx procedures. The anorectum was retrieved with a vascular pedicle containing the aorta in continuity with the inferior mesenteric artery and portal vein in continuity with the inferior mesenteric vein. In the recipient, the native anorectal segment was removed and the graft was transplanted by end-to-side aorta-aorta and porto-cava anastomoses and end-to-end colorectal anastomosis. Recipients were sacrificed at the experimental endpoint on postoperative day 30. Surviving animals resumed normal body weight gain and clinical performance within 5 days of surgery. Isografts and 42.9% of allografts achieved normal clinical evolution up to the experimental endpoint. In 57.1% of allografts, signs of immunological rejection (abdominal distention, diarrhea, and anal mucosa inflammation) were observed three weeks after transplantation. Histology revealed moderate to severe rejection in allografts and no signs of rejection in isografts. We describe a feasible model of ATx in rats, which may allow further physiological and immunologic studies.

Trisulfate Disaccharide Decreases Calcium Overload and Protects Liver Injury Secondary to Liver Ischemia/Reperfusion.

BACKGROUND: Ischemia and reperfusion (I/R) causes tissue damage and intracellular calcium levels are a factor of cell death. Sodium calcium exchanger (NCX) regulates calcium extrusion and Trisulfated Disaccharide (TD) acts on NCX decreasing intracellular calcium through the inhibition of the exchange inhibitory peptide (XIP). OBJECTIVES: The aims of this research are to evaluate TD effects in liver injury secondary to I/R in animals and in vitro action on cytosolic calcium of hepatocytes cultures under calcium overload. METHODS: Wistar rats submitted to partial liver ischemia were divided in groups: CONTROL: (n = 10): surgical manipulation with no liver ischemia; Saline: (n = 15): rats receiving IV saline before reperfusion; and TD: (n = 15): rats receiving IV TD before reperfusion. Four hours after reperfusion, serum levels of AST, ALT, TNF-α, IL-6, and IL-10 were measured. Liver tissue samples were collected for mitochondrial function and malondialdehyde (MDA) content. Pulmonary vascular permeability and histologic parameters of liver were determined. TD effect on cytosolic calcium was evaluated in BRL3A hepatic rat cell cultures stimulated by thapsigargin pre and after treatment with TD. RESULTS: AST, ALT, cytokines, liver MDA, mitochondrial dysfunction and hepatic histologic injury scores were less in TD group when compared to Saline Group (p<0.05) with no differences in pulmonary vascular permeability. In culture cells, TD diminished the intracellular calcium raise and prevented the calcium increase pre and after treatment with thapsigargin, respectively. CONCLUSION: TD decreases liver cell damage, preserves mitochondrial function and increases hepatic tolerance to I/R injury by calcium extrusion in Ca2+ overload situations.

Role of EUS evaluation after endoscopic eradication of esophageal varices with band ligation.

BACKGROUND AND AIMS: Variceal recurrence after endoscopic band ligation (EBL) for secondary prophylaxis is a frequent event. Some studies have reported a correlation between variceal recurrence and variceal rebleeding with the EUS features of paraesophageal vessels. A prospective observational study was conducted to correlate EUS evaluation of paraesophageal varices, azygos vein, and thoracic duct with variceal recurrence after EBL variceal eradication in patients with cirrhosis. METHODS: EUS was performed before and 1 month after EBL variceal eradication. Paraesophageal varices, azygos vein, and thoracic duct maximum diameters were evaluated in predetermined anatomic stations. After EBL variceal eradication, patients were submitted to endoscopic examinations every 3 months for 1 year. We looked for EUS features that could predict variceal recurrence. RESULTS: Thirty patients completed a 1-year endoscopic follow-up. Seventeen patients (57%) presented variceal recurrence. There was no correlation between azygos vein and thoracic duct diameter with variceal recurrence. Larger paraesophageal varices predicted variceal recurrence in both evaluation periods. Paraesophageal varices diameters that best correlated with variceal recurrence were 6.3 mm before EBL (52.9% sensitivity, 92.3% specificity, and .749 area under the receiver operating characteristic curve [AUROC]) and 4 mm after EBL (70.6% sensitivity, 84.6% specificity, and .801 AUROC). CONCLUSIONS: We conclude that paraesophageal varices diameter measured by EUS predicts variceal recurrence within 1 year after EBL variceal eradication. Paraesophageal diameter after variceal eradication is a better recurrence predictor, because it has a lower cut-off parameter, higher sensitivity, and higher AUROC.

Mechanisms of the beneficial effect of sevoflurane in liver ischemia/reperfusion injury.

PURPOSE: To evaluate the underlying mechanisms by which sevoflurane protects the liver against ischemia/reperfusion injury evaluate the mechanism by which sevoflurane exerts this protective effect. METHODS: Twenty-six rats were subjected to partial ischemia/reperfusion injury for 1h: one group received no treatment, one group received sevoflurane, and sham group of animals received laparotomy only. Four hours after reperfusion, levels of alanine and aspartate aminotransferases, tumor necrosis factor-a, and interleukins 6 and 10 were measured. Analyses of mitochondrial oxidation and phosphorylation, malondialdehyde content, histology, and pulmonary vascular permeability were performed. RESULTS: Serum levels of alanine and aspartate aminotransferases were significantly lower in the sevoflurane group compared to untreated controls (p<0.05). The sevoflurane group also showed preservation of liver mitochondrial function compared to untreated controls (p<0.05). Sevoflurane administration did not alter increases in serum levels of tumor necrosis factor-a, and interleukins 6 and 10. Sevoflurane treatment significantly reduced the coagulative necrosis induced by ischemia/reperfusion (p<0.05). Pulmonary vascular permeability was preserved in the sevoflurane group compared to untreated controls. CONCLUSION: Sevoflurane administration protects the liver against ischemia/reperfusion injury, via preservation of mitochondrial function, and also preserves lung vascular permeability.

Mechanisms of the beneficial effect of sevoflurane in liver ischemia/reperfusion injury

PURPOSE: To evaluate the underlying mechanisms by which sevoflurane protects the liver against ischemia/reperfusion injury evaluate the mechanism by which sevoflurane exerts this protective effect. METHODS: Twenty-six rats were subjected to partial ischemia/reperfusion injury for 1h: one group received no treatment, one group received sevoflurane, and sham group of animals received laparotomy only. Four hours after reperfusion, levels of alanine and aspartate aminotransferases, tumor necrosis factor-a, and interleukins 6 and 10 were measured. Analyses of mitochondrial oxidation and phosphorylation, malondialdehyde content, histology, and pulmonary vascular permeability were performed. RESULTS: Serum levels of alanine and aspartate aminotransferases were significantly lower in the sevoflurane group compared to untreated controls (p<0.05). The sevoflurane group also showed preservation of liver mitochondrial function compared to untreated controls (p<0.05). Sevoflurane administration did not alter increases in serum levels of tumor necrosis factor-a, and interleukins 6 and 10. Sevoflurane treatment significantly reduced the coagulative necrosis induced by ischemia/reperfusion (p<0.05). Pulmonary vascular permeability was preserved in the sevoflurane group compared to untreated controls. CONCLUSION: Sevoflurane administration protects the liver against ischemia/reperfusion injury, via preservation of mitochondrial function, and also preserves lung vascular permeability.