Functional regulation of serotonin transporter, a molecule involved in the pathogenesis of anxiety disorder]

The serotonin transporter (SET) is a member of the Na+/Cl(-)-dependent neurotransmitter transporter family and functions as a membrane protein which terminates the serotonergic neuronal transmission by re-uptaking serotonin into the pre-synaptic terminal. SET is thought to be involved in the pathogenesis of affective disorders, drug abuse and anxiety disorder. We have focused on SET regulation by phosphorylation/dephosphorylation since SET has many putative phosphorylation sites in its intracellular region. Our previous studies have revealed that phorbolesters, activators of PKC, decreased in SET uptake activity. Based on a mutagenesis analysis of PKC phosphorylation sites and an in vivo phosphorylation study of SET, we have concluded that PKC regulates SET activity via an indirect mechanism, probably via alternating actin cytoskeleton status. Recent reports and our investigation have demonstrated that the SET C-terminal region interacts with actin binding proteins, suggesting the crucial roles of this region in functional regulation of SET.     

Arachidonate-enriched triglyceride oil does not promote tumor development in a rat medium-term multi-organ carcinogenesis model

The modifying potential on tumor development of arachidonate-enriched triglyceride oil (ARA-oil) containing approximately 40% arachidonic acid was investigated in a medium-term multi-organ carcinogenesis bioassay using male and female F344 rats. The animals were sequentially given five carcinogens with different target sites in the first 4 weeks, and then administered ARA-oil for 24 weeks at dietary levels of 0% (control), 1.25%, 2.5% or 5.0%. No statistically significant differences in incidences and multiplicities of hyperplastic and neoplastic lesions were showed in the large intestine in either sex. In the liver, kidney, and lung in both sexes, and the mammary gland and uterus in females, tumor promoting potential was not evident with ARA-oil treatment. ARA-oil did not affect the quantitative data for glutathione S-transferase placental form positive foci of the liver. Increased induction of hyperplastic or neoplastic lesions in the urinary bladder and thyroid in ARA-oil-treated groups was without dose dependence. In addition, a second experiment with ARA-oil only administration for 8-week revealed no effects on cellular proliferation in the urinary bladder or thyroid in either sex. These results indicate that ARA-oil has no tumor promoting potential in any organs or tissues initiated with the five carcinogens applied in the present study.     

胰腺癌组织中p16基因缺失及其对p16蛋白表达的影响

目的 探讨胰腺癌组织中p16基因缺失状态及其对p16蛋白表达的影响。方法 采用聚合酶链反应技术分别检测经显微切割方法获取的p16蛋白免疫组化染色阳性和阴性的胰腺癌组织中p16基因纯合性缺失状态并将结果与p16蛋白表达之间的关系进行分析。结果 32例胰腺癌中分别有20例（62．5％）和21例（65．6％）表现为p16蛋白表达丢失和p16基因纯合性缺失,其中有5例发生于p16基因的第1外显子,12例缺失发生于第2外显子,1例发生于第3外显子,另有3例同时发生于第1和第2外显子。此外还发现无p16蛋白表达的胰腺癌组织发生p16基因纯合性缺失的比例（18／20,90．0％）高于有p16蛋白表达的胰腺癌（3／12,25．0％）;在无p16蛋白表达并伴有p16基因缺失的7例胰腺癌病人中仅有1例生存期超过5mo,而二者均无异常的3例胰腺癌的生存期均超过8mo。结论 胰腺癌组织中的p16基因纯合性缺失可以影响p16蛋白的表达,促使胰腺癌病人的预后更差。     

Substituted 3-phenylsulfonylquinazoline-2,4-dione derivatives as novel nonpeptide inhibitors of human heart chymase

A series of 3-phenylsulfonylquinazoline-2,4-dione derivatives have been synthesized and evaluated for their ability to inhibit human heart chymase. The structure-activity relationship studies on these compounds gave the following results. The phenyl moiety of quinazoline participates in a hydrophobic interaction where an optimum size is required. In this moiety, 7-chloroquinazoline is the best moiety for inhibiting chymase, chymotrypsin and cathepsin G. A 3-phenylsulfonyl moiety substituted with hydrophobic electron-withdrawing groups at the 4-position potentiated the activity. Anthranil moiety also enhanced the activity. Pyridylmethyl and N-pyridylacetamide at the 1-position gave an IC50 in the order of 10(-8)M. Molecular modeling studies on the interaction of 7-chloro-3-(4-chlorophenylsulfonyl) quinazoline-2,4(1H, 3H)-dione (4) with the active site of human heart chymase suggested that the phenyl moiety of quinazoline interacts with the hydrophobic P1 pocket, the 3-phenylsulfonyl moiety resides in the S1'-S2' subsites, the moiety at the 1-position locates in the S2-S3 subsites and the 4-carbonyl and 3-sulfonyl group interact with the oxyanion hole and the His57 side-chain of chymase, respectively.     

A questionnaire about radiation safety management of the draining-water system at nuclear medicine facilities

We conducted a questionnaire survey about radiation-safety management condition in Japanese nuclear medicine facilities to make materials of proposition for more reasonable management of medical radioactive waste. We distributed a questionnaire to institutions equipped with Nuclear Medicine facilities. Of 1,125 institutions, 642 institutes (52.8%) returned effective answers. The questionnaire covered the following areas: 1) scale of an institution, 2) presence of enforcement of radiotherapy, 3) system of a tank, 4) size and number of each tank, 5) a form of draining-water system, 6) a displacement in a radioactive rays management area, 7) a measurement method of the concentration of medical radioactive waste in draining water system, 8) planned and used quantity of radioisotopes for medical examination and treatment, 9) an average displacement of hospital for one month. In most institutions, a ratio of dose limitation of radioisotope in draining-water system was less than 1.0, defined as an upper limitation in ordinance. In 499 hospitals without facilities of hospitalization for unsealed radioisotope therapy, 473 hospitals reported that sum of ratios of dose limits in a draining-water system was less than 1.0. It was calculated by used dose of radioisotope and monthly displacement from hospital, on the premise that all used radioisotope entered in the general draining-water system. When a drainage including radioactivity from a controlled area join with that from other area before it flows out of a institution, it may be diluted and its radioactive concentration should be less than its upper limitation defined in the rule. Especially, in all institutions with a monthly displacement of more than 25,000 m3, the sum of ratio of the concentration of each radionuclide to the concentration limit dose calculated by used dose of radioisotope, indicated less than 1.0.     

Clinical Characteristics of Portal Hemodynamics in Alcoholic Liver Cirrhosis

Background: Low incidence of reversal blood flow at the portal vein has been reported by measurement in larger and extrahepatic blood vessels but not in intrahepatic blood vessels in patients with liver cirrhosis. Moreover, there is little information regarding the incidence of reversal blood on the basis of the cause of liver cirrhosis. The aim of this study was to measure the reversal blood flow in the portal vein including intrahepatic branches in patients with alcoholic and viral cirrhosis.
Methods: The blood flow in the portal vein and existence of portosystemic shunt were studied in 52 and 27 patients with alcoholic and viral cirrhosis, respectively, by Doppler ultrasonography. The parameters of liver function test and the prevalence of ascites and esophageal varices were compared between patients with and without reversal blood flow.
Results: Reversal blood flow at the portal vein was found only in patients with only alcoholic cirrhosis (17 of 52 patients) but not in any patients with viral cirrhosis (0 of 27 patients; p < 0.05). The incidence of portosystemic ascites and red color of esophageal varices was also higher in patients with alcoholic cirrhosis with reversal blood flow in the portal vein compared with patients without reversal blood flow ( p < 0.05).
Conclusions: Reversal blood flow in the portal vein is a characteristic feature of alcoholic cirrhosis. The presence of reversal blood flow indicates severe liver diseases, and this feature may have prognostic importance for patients with alcoholic cirrhosis.     

Efficacy and anticarcinogenic activity of interferon for hepatitis C virus-related compensated cirrhosis in patients with genotype 1b low viral load or genotype 2

Background: We assessed the efficacy and anticarcinogenic effects of interferon (IFN) therapy in patients with hepatitis C virus (HCV)-related cirrhosis. Methods: The study subjects were 123 Japanese patients with HCV-related cirrhosis with genotype 1b low viral load or genotype 2 who received IFN from 1989 to 2005 (18 patients continue to receive IFN therapy). They included 81 men and 42 women aged 29-74 years (median, 56 years). Results: Univariate analysis identified four parameters that significantly influenced SVR; viral load (low HCV concentration, P < 0.001), duration of IFN therapy (>/= 52 weeks, P = 0.029), daily dose of IFN (>/= 6 million units, P = 0.018), induction therapy (presence, P = 0.010) and choline esterase (> 1.0 DeltapH, P = 0.037). Multivariate analysis identified viral load (risk ratio = 6.329, P < 0.001) and daily dose of IFN (risk ratio = 2.62, P = 0.042) as two independent parameters thatinfluenced SVR. During the observation period, newly developed hepatocellular carcinoma (HCC) was detected in 22 patients. The rates of development of HCC in patients with SVR were 5.8% at the fifth year and 10.3% at the 10th year, compared with 25.8% at the fifth year and 42.5% at the 10th year in non-SVR patients. Multivariate analysis showed that IFN efficacy (SVR) was the only independent factor of hepatocarcinogenesis (hazard ratio: 0.185, 95% confidence interval: 0.042-0.810, P = 0.025) Conclusion: Among patients with HCV-related cirrhosis, the rate of development of HCC is significantly less in patients with SVR.