The nuclear 16-kD protein methylation increases in the early period of liver regeneration in a hepatectomized rat

Methylation events play a critical role in various cellular processes including regulation of gene transcription and proliferation. We observed that methyltransferase activity underwent time-dependent changes in the cytosol of the rat hepatocytes upon partial hepatectomy. However, any change in the methylation of nuclear proteins is not clear during hepatocyte proliferation. The nuclear fraction possesses basal level of methyltransferase to catalyze methylation of several proteins ranging from 7 to 70 kD prior to any hepatecmony. The specific p16 (16 kD) band was transiently and heavily methylated post 1 day hepatectomy, and then became non- detectable, but not in the control liver. Methylation of p16 band was completely inhibited by exogenously added histones, particularly 2AS, 1, 2A and 2B subtypes. The methylated p16 protein remains stable in either acid or alkali- induced demethylation conditions, indicating that methylation is not likely to occur on isoaspartyl or C-terminal cysteinyl residues. Exogenous addition of non-hydrolyzable GTP caused a dose- dependent suppression of a p16 methylation suggesting that G-proteins might play a role as an endogenous methylation inhibitor in vivo. Taken together, we have identified the proliferation event associated-methylation of the nuclear p16 protein in the hepatocytes undergoing liver regeneration.

Immunostimulatory effects of anionic alkali mineral complex solution Barodon in porcine lymphocytes

The anionic alkali mineral complex solution, Barodon (Barodon-S.F. Corp., Korea), was evaluated for its effectiveness as a nonspecific immunostimulator in pigs. The effects of Barodon were determined by analysis of feed efficiency, growth rate, and phenotype of leukocyte subpopulations using monoclonal antibodies specific to porcine leukocyte differentiation antigens and flow cytometry (FC). The study was focused to investigate the change in proportion of the CD4+CD8+ double positive T lymphocyte subpopulation (dpp) which exists uniquely in pigs. In addition, the mitogen-stimulated lymphoproliferative response, tissue distribution in lymphoid organs and the adjuvant effect of Barodon on hog cholera vaccine efficiency were determined. The study has revealed the average daily gain rates and feed conversion rates were significantly (p<0.05) improved in either group of pigs fed with 0.05% Barodon-spray feed (Tx-1) or pigs fed with 3% Barodon-fermented feed (Tx-2) in comparison with group of pigs fed with feed containing no Barodon (control). The proportion of cells expressing CD4+ antigen in Barodon-treated group increased from 3 weeks posttreatment and was significantly higher (p<0.05) than that of control at 8 weeks posttreatment. Particularly, the significantly higher proportion was maintained from 8 weeks through 13 weeks posttreatment in Tx-1 group (p<0.05). The proportion of cells expressing CD8+ antigen was significantly higher at 3 weeks posttreatment in Tx-2 (p<0.01). Proportion of MHC class II-expressing cells was significantly higher in Tx-1 and Tx-2 group at 11 weeks and 8 weeks posttreatment (p<0.05), respectively. In addition, the proportion of Non T/Non B (N) cells was also significantly higher in Tx-2 at 3 weeks posttreatment (p<0.01) and maintained to 13 weeks posttreatment (p<0.1). Between Barodon-treated groups, the proportion of MHC class II-expressing cells was observed to be larger in Tx-2 than Tx-1 from 3 weeks to 8 weeks posttreatment (p<0.05). However, there were no significant difference in the proportions of CD2+ cells, B cells, monocytes and granulocytes between Barodon-treated and control group during the experiment. Dual-color FC analysis, study has revealed an increased proportion of dpp present in lymphocytes obtained from peripheral blood (PB) and mesenteric lymph node (MLN) of Barodon-treated group at 8 and 11 weeks posttreatment. The proportion of dpp in PB was 27.5% and 32.1% in Tx-1 and Tx-2, respectively, but only 2.2% in control group at 8 weeks posttreatment. In MLN, the proportion was 45.1% and 52.1% in Tx-1 and Tx-2, respectively, otherwise 16.5% in control group at 8 weeks posttreatment. The mitogen-stimulated activity was significantly higher in Tx-1 than in the control group at 11 weeks posttreatment when cells were stimulated with Con A and PHA, respectively (p<0.01). Also, Con A-, PHA and PWM-stimulated activity was significantly higher in Tx-2 than in the control group at the same time (p<0.05). The tissue distribution of CD4+, CD8+ and CD4+CD8+ dpp in MLN and spleen was significantly larger in Tx-1 and Tx-2 than in the control group (p<0.01). Also, a larger proportion of dpp was observed in Tx-2 than Tx-1 in spleen between Barodon-treated groups (p<0.01). In conclusion, the study has demonstrated that Barodon had an immunostimulatory effect on pigs through proliferation and activation of porcine immune cells, specially CD4+CD8+ dpp lymphocytes.

Alcalinizaçäo da ropivacaína 0, 75 por cento para bloqueio peridural / Alkalization of 0, 75 per cent ropivacaine for epidural block

Justificativa e objetivos: näo encontramos na literatura estudos clínicos sobre a alcalinizaçäo da ropivacaína. Os objetivos deste estudo foram: a)determinar a quantidade de NaHCO3 que alcaliniza a ropivacaína 0,75 por cento (com e sem adrenalina); b) averiguar as alteraçöes físico-químicas decorrentes desta alcalinizaçäo; c) verificar se a ropivacaína alcalinizada provoca bloqueio peridural de melhor qualidade, no que se refere à latência sensitivo-motora, à dispersäo e a duraçäo da anestesia. Método: foi determinado em laboratório que 0,012 e 0,015 mEQ de NaHCO3 respectivamente alcalinizam 10ml das soluçöes de ropivacaína 0,75 por cento sem e com adrenalina (1:200.000). Na segunda fase o estudo foi aleatório e duplamente encoberto envolvendo 60 pacientes divididos em três grupos de 20 (G1, G2 e G3) que recebram respectivamente, através de bloqueios peridurais lombares, 10ml de ropivacaína 0.75 por cento mais 0,5ml de NaCI 0,9 por cento (soluçäo A), 10ml de ropivacaína 0.75 por cento mais 0,012 mEq de NaHCO3 (soluçäo B) e 10ml de ropivacaína 0,75 por cento (com adrenalina) mais 0,015 mEq de NaHCO3 (soluçäo C). O pH, PCO2 e as fraçöes näo-ionizadas das soluçöes de ropivacaína 0,75 por cento foram aferidas antes e após a adiçäo de NaCI 0,9 por cento ou NaHCO3 ou adrenalina e NaHCO3. Foram avaliadas as latências sensitivas e motoras, a dispersäo e a duraçäo do bloqueio. Resultados: os valores do pH, PCO2 e das fraçöes näo-ionizadas elevaram-se significativamente nas soluçöes B e C, em relaçäo à soluçäo A. Näo foram observadas diferenças entre os grupos em relaçäo à dispersäo e à latência sensitivo-motora. A duraçäo dos bloqueios sensitivos foi significativamente maior nos pacientes dos grupos G2 e G3. Conclusöes: a quantidade de NaHCO3 para alcalinizar 10ml de ropivacaína 0,75 por cento à temperatura ambiente é de 0,012 mEq. Quando a soluçäo contém adrenalina 1:200.000 (5µg.ml-1) pode-se adicionar até 0,015 mWq de NaHCO3. A alcalinizaçäo da soluçäo de ropivacaíns 0,75 por cento näo ocasionou reduçäo da latência sensitivo-motora. No entanto, proporcionou significativo aumento da duraçäo do bloqueio peridural, sem diferenças significativas entre as soluçöes com e sem adrenalina