Effects of phenol, glycerin and acetic acid on the liver of guinea pigs

OBJETIVO: Investigar a ação histolítica da solução composta de fenol, glicerina e ácido acético para os casos de metástases hepáticas não ressecáveis. MÉTODOS: Foram utilizadas 32 cobaias, distribuídas, por sorteio, em quatro grupos: experimental (24 horas e quatro semanas) e controle (24 horas e quatro semanas); todos os animais foram submetidos a laparotomia mediana e realizada a injeção da solução E (grupo experimental) ou solução fisiológica (grupo controle). Foram estudadas as alterações bioquímicas e anatomopatológicas (fígado) com 24 horas e quatro semanas de evolução. RESULTADOS: Verificou-se que a solução E produz necrose delimitada à área infiltrada apos 24 horas e que ao final de quatro semanas ocorreu regeneração do tecido hepático com formação de discreta área de fibrose. Não foram observadas quaisquer alterações bioquímicas tanto no grupo experimental como controle. CONCLUSÃO: Frente aos resultados obtidos, é válido considerar-se a possibilidade do emprego da solução proposta, nos casos de metástases hepáticas não ressecáveis.

Liver dysfunction in patients bitten by Crotalus durissus terrificus (Laurenti, 1768) snakes in Botucatu (State of São Paulo, Brazil)

Os autores estudaram 32 doentes picados por serpentes venenosas, sendo 16 picados por Bothrops spp. e 16 por Crotalus durissus terrificus. Trinta doentes eram do sexo masculino e dois do feminino com idades variando entre 8 e 63 anos (méda 33±15). A prova da retenção da bromosulfaleína apresentou-se aumentada na maioria dos doentes picados por serpentes Crotalus durissus terrificus. Houve correlação positiva entre a retenção da bromosulfaleína e os níveis séricos de alanina aminotransferase e entre alanina e aspartato aminotransferase apenas nos doentes do grupo Crotalus. Um dos doentes evoluiu para o óbito e apresentou no exame anatomopatológico do fígado degeneração hidrópica e lesões mitocondriais. Os autores concluem que as alterações hepáticas são causadas por pelo menos dois mecanismos a saber: lesão mitocondrial por efeito do veneno crotálico; efeito das citoquinas, especialmente a interleucina-6.

Interferon Alpha-2B and liver resection to treat multifocal hepatic epithelioid hemangioendothelioma: A relevant approach to avoid liver transplantation

Background. Hepatic epithelioid hemangioendothelioma is a rare malignant tumor of vascular origin with frequent multifocal appearance. Liver resection may cause tumor spread. Liver transplantation has been indicated for unresectable nodules. We hypothesized that adjuvant interferon treatment is effective to prevent metastasis after liver resection. We report a case of multifocal hepatic epithelioid hemangioendothelioma successfully treated with interferon pulse therapy and bilobar hepatic resection.Methodology. CT scan and magnetic resonance imaging diagnosed three nodules in the liver (segments IV, VI and VII). Histopathology and specific immunostaining of a percutaneous nodule biopsy confirmed the diagnosis of hepatic epithelioid hemangioendothelioma. The treatment protocol included daily interferon alpha 2b 9 weeks before and 1 week after resection of liver segments IV, VI and VII.Results. The postoperative outcome was complicated by a self-limited biliary fistula. The patient remains tumor free at 3 years after liver resection and currently enjoys excellent health.Conclusion. Interferon pulse therapy and hepatic resection was a good option to treat multifocal bilobar hepatic epithelioid hemangioendothelioma; it may prevent metastasis dissemination.

Effect of acute heat stress on heat shock protein 70 messenger RNA and on heat shock protein expression in the liver of broilers

1. The synthesis of heat shock protein 70 (Hsp70) mRNA and the expression of Hsp70 in the liver of broiler chickens submitted to acute heat stress (35 degrees C for 5 h) was investigated.2. Hsp70 expression was detected by SDS-PAGE and Western blot analysis using a polyclonal antiserum against Hsp70 of Blastocladiella emersonii. The specific signal of Hsp70 mRNA was analysed by Northern blot using as probe a Hsp70 cDNA of B. emersonii.3. An increase in the amount of Hsp70 was detected from the first up to the fifth hour of acute heat exposure. This increase in the amount of Hsp70 was accompanied by an increase in Hsp70 mRNA which peaked at 3 h.4. This study shows that the heat induced increase in Hsp70 mRNA and protein in broiler liver, in vivo, are time dependent, similar to that in mammals.

CHOLESTEROL MODULATION OF LIPID PROTEIN INTERACTIONS IN LIVER MICROSOMAL MEMBRANE - A SPIN LABEL STUDY

ESR spectra of spin probes were used to monitor lipid-protein interactions in native and cholesterol-enriched microsomal membranes. In both systems composite spectra were obtained, one characteristic of bulk bilayer organization and another due to a motionally restricted population, which was ascribed to lipids in a protein microenvironment. Computer spectral subtractions revealed that cholesterol modulates the order/mobility of both populations in opposite ways, i.e., while the lipid bilayer region gives rise to more anisotropic spectra upon cholesterol enrichment, the spectra of the motionally restricted population become indicative of increased mobility and/or decreased order. These events were evidenced by measurement of both effective order parameters and correlation times. The percentages of the motionally restricted component were invariant in native and cholesterol-enriched microsomes. Variable temperature studies also indicated a lack of variation of the percentages of both spectral components, suggesting that the motionally restricted one was not due to protein aggregation. The results correlate well with the effect of cholesterol enrichment on membrane-bound enzyme kinetics and on the behavior of fluorescent probes [Castuma & Brenner (1986) Biochemistry 25, 4733-4738]. Several hypothesis are put forward to explain the molecular mechanism of the cholesterol-induced spectral changes.

Factors affecting metabolic and electrolyte changes after reperfusion in liver transplantation

Background. The metabolic and electrolyte changes were evaluated after various durations of cold and warm ischemia times to correlate ASA status with hemodynamic changes that may affect the severity of the reperfusion syndrome.Patients and methods. Sixty-one patients who underwent liver transplantation (OLT) were monitored by arterial pH, PaO2, PaCO2, HCO3, BE, K+, Ca2+, Na+, GL, and serial Ht at three specific times: after the skin incision (baseline), 10 minutes before reperfusion (T-2), and 10 minutes after reperfusion (T-3). Changes in metabolic parameters were correlated with ASA status, hemodynamic changes, time of OLT, as well as cold and warm ischemia times.Results. The pH in ASA IV patients was significantly lower at T-1 and T-3, and PCO2 higher in ASA V at T-1. A significant correlation was observed between pH, PaCO2, HCO3 BE, Na+, Ca2+, and glucose with the phase of the procedure. The pH and HCO3 decreased significantly from T-1 and T-2, increasing during T-3. Ca2+ fell from T-1 to T-2 increasing in T-3. Mean glucose and sodium levels increase from T-1 to T-3. Mean BE dropped from T-1 to T-2 and increased at T-3 without a significant correlation between the metabolic parameters in any phase of the study and the cold or warm ischemia times. Patients with a high ASA status showed an increased risk for cardiovascular collapse after reperfusion.Conclusions. Patients with advanced ASA status are more prone to metabolic and acid-base disturbances during reperfusion, without any relation to the cold or warm ischemia times. High ASA status shows an increased risk for cardiovascular collapse after reperfusion.

Diuron lacks promoting potential in a rat liver bioassay

The promoting activity of the herbicide Diuron was evaluated in a medium-term rat liver carcinogenesis bioassay that uses as endpoint immunohistochemically identified glutathione S-transferase positive (GST-P+) foci. Male Wistar rats were allocated to the following groups: G1 to G6 were initiated for liver carcinogenesis by a single dose of diethylnitrosamine (DEN, 200 mg/kg) while groups G7 and G8 received only 0.9% NaCl (DEN vehicle). From the 2nd week animals were fed a basal diet (G1 and G7) or a diet added with Diuron at 125, 500, 1250, 2500 and 2500 ppm (G2 to G5 and G8, respectively) or 200 ppm Hexaclorobenzene (HCB; G6). The animals were submitted to 70% partial hepatectomy at the 3rd week and sacrificed at the 8th week. The herbicide did not alter ALT or creatinine serum levels. No conspicuous GST-P+ foci development was registered in non-initiated rats fed Diuron at 2500 ppm. While DEN-initiated animals fed Diuron at 1250 or 2500 ppm developed mild centrilobular hypertrophy, DEN-initiated HCB-fed animals showed severe liver centrilobular hypertrophy and significant GST-P+ foci development. These findings indicate that the medium-term assay adopted in this study does not reveal any liver carcinogenesis initiating or promoting potential of Diuron in the rat.

Liver lesions produced by aflatoxins in Rana catesbeiana (bullfrog)

This study describes alterations induced in Rana catesbeiana (bullfrog) liver after extended dietary exposure to aflatoxins (AFs). Bullfrogs of both sexes were fed for 120 days a commercial chow blended with a rice bran-based mixture of Al's containing 667.0, 11.65, 141.74, and 3.53 mg/kg of AFs B1, B2, G1, and G2, respectively. Animals were sacrificed on study days 45, 90, and 120. Severe and progressive liver lesions with structural collapse, increased hepatocyte and biliary duct cell proliferation, appearance of basophilic hepatocytes, and diffuse scarring, were observed at all time points. There were no quantitative alterations in the liver melanomacrophage centers of the AFs-exposed animals. Increased amounts of lipid hydroperoxides, indicative of ongoing oxidative stress, were more evident in the Addutor magnum muscle than in the AFs-damaged livers. No tumors were found in the R. catesbeiana livers after 120 days of exposure to relatively high doses of AFs. (c) 2006 Elsevier B.V. All rights reserved.

Purification and partial characterization of cathepsin D from porcine (Sus scrofa) liver using affinity chromatography

Cathepsin D, a lysosomal aspartic protease, has been purified from porcine liver using a combination of pepstatin-A agarose and Affi-Gel Blue affinity chromatography, followed by size-exclusion chromatography. The purified protein consists of two polypeptide chains of 15 and 30 kDa, and has an isoelectric point of 6.8. Porcine liver cathepsin D has maximum activity at pH 2.5-3.0 as determined by its activity against hemoglobin, with a K-cat of 14.3 s(-1) and a k(cat)/K-M of 2.70 x 10(6) s(-1) M-1 as determined by the hydrolysis of a fluorogenic peptide substrate.

Serologic profile in hepatitis B virus and hepatitis C virus in a Brazilian liver transplant waiting list

Chronic viral hepatitis is currently the most common indication for liver transplantation (OLT). Knowing the serological profile of patients on the liver transplant waiting list (LTWL) is essential to manage prophylactic and therapeutic strategies pre- and post-OLT. The aim of this study was to determine the hepatitis B virus (HBV) and hepatitis C virus (HCV) serological profile on the LTWL.Methods. Serological data were collected from 44 candidates included on, the LTWL from May 2003 to November 2004. HBV and HCV serological profiles were performed by microenzyme immunoassay.Results. Twenty-eight patients (66.7%) lacked H13V serological markers. Anti-HBs was detected in 9.5% and was positive for HBsAg, anti-HBc, IgM anti-HBc, or HbeAg in 4.8% of patients, probably related to reactivation of chronic infection. In 7.1% of patients, the markers demonstrated serological cure of infection. In HCV patients, 41.5% were positive. There was H13V and HCV co-infection in 12.2% of patients.Conclusion. HBV infection in 21.4% of the patients corroborates the need to use more efficient protocols for prophylactic and therapeutic management pre- and post-OLT. The high prevalence of HCV infection reinforces the need to follow adequate protocols to avoid related complications and guarantee rational and universal use of more efficient drugs.