Quantitative analysis of K-ras gene mutation in pancreatic tissue obtained by endoscopic ultrasonography-guided fine needle aspiration: clinical utility for diagnosis of pancreatic tumor

OBJECTIVES: Endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) has become established in the diagnosis of pancreatic cancer. The combination of pathological diagnosis and analysis for mutant K-ras gene was investigated to improve the accuracy of diagnosis. METHODS: EUS-FNA was performed in 34 patients with pancreatic masses (26 adenocarcinomas and eight chronic pancreatitis). Mutant ras gene was analyzed semiquantitatively in the specimens obtained by EUS-FNA as well as in pancreatic juice obtained by ERCP. RESULTS: Mutant gene was detected at high amounts (more than 2% of total ras genes) in 20 of 26 (77%) specimens of EUS-FNA and in 12 of 19 (63%) of pancreatic juice in cases with pancreatic carcinoma. Cytological diagnosis of malignancy by EUS-FNA was found in 16 of 26 (62%) patients with pancreatic cancer. Accurate diagnosis of the carcinoma was 21 of 26 (81%) by combined cytology and molecular method of EUS-FNA, and increased to 23 of 26 (88%) by adding molecular analysis of pancreatic juice. In contrast, mutant gene was absent or low level despite suspicious cytology in patients with benign pancreatic lesion. CONCLUSION: Quantitative analysis of mutant ras gene supplemented conventional cytology of EUS-FNA and ERCP. Detection of mutation at high amounts may represent pancreatic cancer, whereas its absence increased the possibility of benign lesion.     

Antimicrobial and microbicidal activities of tea and catechins against Mycoplasma]

We examined tea extracts, (-) epigallocatechin gallate (EGCg) and theaflavin digallate (TF3) for their antimicrobial and microbicidal activities against Mycoplasma. Green tea and black tea showed antimicrobial activities against M. pneumoniae. At a concentration of 0.2% green tea and black tea showed microbicidal activities against M. pneumoniae and M. orale but not against M. salivarium. Extracts of pu-erh tea showed a slight microbicidal activity against M. pneumoniae and M. orale. EGCg purified from green tea and TF3 from black tea markedly showed microbicidal activities against M. pneumoniae. M. orale and M. salivarium. These results suggest that tea and catechins can be used as prophylactic agents against Mycoplasma pneumoniae infection.     

Splenectomy-reduced hepatic injury induced by ischemia/reperfusion in the rat

Abstract: In the present study, we investigated the role of the spleen in experimental hepatic ischemia/reperfusion in the rat. After a 90-min period of ischemia in the left and middle hepatic lobes, the ischemia was released and the liver was reperfused for up to 24 h. Plasma alanine aminotransferase reached a peak 3 h after the onset of reperfusion, and gradually decreased thereafter. A histological examination revealed evidence of hepatocellular necrosis and degeneration, especially 24 h after the onset of reperfusion. In addition, there was a noticeable accumulation of polymorphonuclear cells in the liver following ischemia/reperfusion. A splenectomy performed just prior to ischemia/reperfusion reduced both biochemical and histological hepatocellular injury. The number of polymorphonuclear cells in the liver following ischemia/reperfusion was significantly reduced in rats subjected to splenectomy, suggesting that the increase in polymorphonuclear cells may contribute to liver injury. The number of mononuclear cells also increased in the marginal zones of the spleen following ischemia/reperfusion, and appeared to be derived from the splenic monocyte/macrophage population, based on immunohistochemical studies. The spleen plays an important role in the pathogenesis of hepatic ischemia/reperfusion injury and the splenic monocyte/macrophage population contributes to liver damage.     

Maturation of Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes by Soluble Factors from Human Mesenchymal Stem Cells

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Evidence for a putatively new angiotensin II-generating enzyme in the vascular wall

An inhibitor of angiotensin I (ANG I) converting enzyme, SA446, reduced the response to ANG I of blood vessels isolated from dogs and monkeys, but did not abolish the response even at high concentrations. The residual action of ANG I in the presence of high concentrations of SA446 could be abolished by (Sar1, Ala8)-ANG II. Vascular strips and crude extracts of vessels and lungs possessed the enzymic activity generating ANG II from ANG I, or hippuric acid from hippuryl-histidyl-leucine (HHL). The HHL-hydrolysing activity of the crude extracts was completely inhibited by SA446 (10(-7) mol/l) and/or Na2-EDTA (10(-3) mol/l). However, the octapeptide generation was not abolished despite the combined treatment with SA446 (5 X 10(-4) mol/l) and Na2-EDTA (5 x 10(-3) mol/l). The residual activity forming ANG II was inhibited by chymostatin and soybean trypsin inhibitor, which however did not affect the HHL-hydrolysis. Combined treatment with SA446 (10(-5) mol/l) and chymostatin (2.5 X 10(-5) mol/l) abolished the vascular action of ANG I but did not alter the action of ANG II. These results strongly suggest that besides the ANG I converting enzyme, another enzyme which generates ANG II is present in vascular tissues and lungs, and may play an important role in the local generation of ANG II, which possibly regulates the regional vascular tone.     

Alcohol-Metabolizing Enzyme Polymorphisms and Alcoholism in Japan

The liver enzymes, alcohol dehydrogenase (ADH) and aldehyde de-hydrogenase (ALDH), which are responsible for the oxidative metabolism of ethanol, are polymorphic in humans. Cytochrome P450IIE1 , an ethanol-inducible isozyme of liver microsomal P450 , is also important in ethanol metabolism. Genetic polymorphisms in the 5'-flanking region of the human cytochrome P450IIE1 gene have recently been reported. We hypothesized that the polymorphisms of ADH , ALDH , and P450IIE1 modify the susceptibility to development of alcoholism. We determined the genotypes of the ADH2 , ALDH2 , and P450IIE1 loci of 96 Japanese alcoholics and 60 healthy male subjects, using leukocyte DNA by the restriction fragment-length polymorphism by polymerase chain reaction. The alcoholics had significantly higher frequencies of the ADH2 ¹ and ALDH2 ¹ alleles than did the healthy subjects. No significant difference in the frequency of the P45011E1 genotype was observed between the alcoholics and the healthy subjects. In conclusion, genetic polymorphisms of the ADH and ALDH genes, but not of the P45011E1 gene, influence the risk of developing alcoholism in Japanese.