Discrimination among the Clinical Isolates of Candida albicans by Amplification of the Repetitive Sequences,alts

A primer pair, PB and BSH, which amplified alts, a portion of Candida albicans-specific repetitive sequence, RPS, gave stable and reproducible fingerprint patterns of the strains by polymerase chain reaction (PCR). We applied this method to clinical isolates of C. albicans for strain discrimination. Using PCR fingerprint patterns, we could analyze the relatedness of C. albicans strains including those isolated from children with leukemia and their bedside parents. The results indicated that PCR analysis targeting an alt region gives rise to the same conclusion as the previous study obtained by SmaI RFLP analysis.     

Cleavage of mRNAs and role of tmRNA system under amino acid starvation in Escherichia coli

We have shown previously that ribosome stalling during translation caused by various reasons leads to mRNA cleavage, resulting in non-stop mRNAs that are eliminated in a tmRNA-dependent manner. Amino acid starvation is a physiological condition in which ribosome stalling is expected to occur more frequently. Here we demonstrate that mRNA cleavage is induced by amino acid starvation, resulting in accumulation of truncated mRNAs in cells lacking tmRNA. The truncated mRNAs are eliminated in wild-type cells, indicating that the tmRNA system rapidly degrade the truncated mRNAs. The cleavage pattern of model mRNAs in which serine codons were replaced with threonine codons indicated that mRNA cleavage occurs near serine codons in response to serine starvation. Cells lacking all of the five known toxin loci were proficient in mRNA cleavage, showing that toxin–antitoxin systems are not responsible for the cleavage. A mild serine starvation caused a significant growth inhibition in cells lacking tmRNA but not in wild-type cells. The ribosome-mediated mRNA cleavage along with the tmRNA system is an important mechanism that enables cells to adapt to amino acid starvation conditions.     

Ganoderiol A and B,New Triterpenoids from the Fungus Ganoderma lucidum (Reishi)

Two new lanostane-type triterpenoids, ganoderiol A (1) and ganoderiol B (2) were isolated from the fruiting bodies of Ganoderma lucidum, together with known ganodermanontriol (3) and ganodermatriol (4). The compounds were identified as 5α-lanosta-7,9(11)-dien-3β,24,25,26-tetraol (1), 15α,26,27-trihydroxy-5α-lanosta-7,9(11),24-trien-3-one (2), 24,25,26-trihydroxy-5α-lanosta-7,9(11)-dien-3-one (3) and 5α-lanosta-7,9(ll),24-trien-3β,26,27-triol (4), respectively.     

Angiotensin II induces oxidative stress in prostate cancer

Angiotensin II has been shown to be a cytokine especially acting as a growth factor. A local renin-angiotensin system has been identified in the prostate gland, and the physiologic function of angiotensin II seems to be similar in prostate cancer, as we previously reported. In the present study, we explored the biological role of angiotensin II in oxidative stress of prostate cancer cells. Activated Akt was determined, and the expression of oxidative stress-related proteins (p47phox, manganese superoxide dismutase 2, glutathione peroxidase) was examined by Western blotting in LNCaP cells, which were stimulated with angiotensin II and/or an angiotensin II receptor type 1 blocker, candesartan. To examine DNA damage induced by angiotensin II, 8-hydroxy-2'-deoxyguanosine was determined, and Western blots were analyzed to detect checkpoint proteins including p53, Chk2, and cdc2. Immunocytochemical studies of inducible nitric oxide synthase and superoxide anion radical (O(2)(-)) were done in LNCaP cells stimulated with angiotensin II. The phosphorylation of Akt was induced by angiotensin II treatment and inhibited by candesartan, as well as by LY294002, an inhibitor of phosphoinositide 3-kinase. Oxidative stress-related proteins were up-regulated by angiotensin II and inhibited by pretreatment with candesartan or catalase. The level of 8-hydroxy-2'-deoxyguanosine was increased by angiotensin II and conversely decreased by candesartan. Immunocytochemical studies showed that angiotensin II enhanced an inflammatory marker, inducible nitric oxide synthase, and the production of O(2)(-) radical. The hypothesis that angiotensin II has the potential to induce oxidative stress, which may be implicated in carcinogenesis of the prostate gland through long-term exposure to chronic inflammation is proposed.     

A mass occurrence of human infection with Diplogonoporus grandis (Cestoda: Diphyllobothriidae) in Shizuoka Prefecture, central Japan

Forty-six cases of human infection with Diplogonoporus grandis were found in Shizuoka Prefecture on the Pacific coast of Central Japan in 1996. The cases were predominantly elderly male patients over 50 years of age. Although all cases were reported from May to September of the year, most of them were diagnosed in June and July. We suspected that the transmission was due to the consumption of raw juvenile Japanese anchovy (Engraulis japonicus), which are seasonally caught in the spring months off the Pacific coast of the Prefecture. In almost a hundred years after its discovery in 1894, there had been more than 180 cases of human diplogonoporiasis recorded in Japan. The high incidence within a relatively short time frame of our investigation is regarded unusual even in this country.     

NDRG4 protein-deficient mice exhibit spatial learning deficits and vulnerabilities to cerebral ischemia

The N-myc downstream-regulated gene (NDRG) family consists of four related proteins, NDRG1-NDRG4, in mammals. We previously generated NDRG1-deficient mice that were unable to maintain myelin sheaths in peripheral nerves. This condition was consistent with human hereditary motor and sensory neuropathy, Charcot-Marie-Tooth disease type 4D, caused by a nonsense mutation of NDRG1. In contrast, the effects of genetic defects of the other NDRG members remain unknown. In this study, we focused on NDRG4, which is specifically expressed in the brain and heart. In situ mRNA hybridization on the brain revealed that NDRG4 was expressed in neurons of various areas. We generated NDRG4-deficient mice that were born normally with the expected Mendelian frequency. Immunochemical analysis demonstrated that the cortex of the NDRG4-deficient mice contained decreased levels of brain-derived neurotrophic factor (BDNF) and normal levels of glial cell line-derived neurotrophic factor, NGF, neurotrophin-3, and TGF-β1. Consistent with BDNF reduction, NDRG4-deficient mice had impaired spatial learning and memory but normal motor function in the Morris water maze test. When temporary focal ischemia of the brain was induced, the sizes of the infarct lesions were larger, and the neurological deficits were more severe in NDRG4-deficient mice compared with the control mice. These findings indicate that NDRG4 contributes to the maintenance of intracerebral BDNF levels within the normal range, which is necessary for the preservation of spatial learning and the resistance to neuronal cell death caused by ischemic stress.     

Effect of AOB, a fermented-grain food supplement, on oxidative stress in type 2 diabetic rats

Reactive oxygen species (ROS) play an important role in the pathogenesis of diabetic complications. Antioxidant Biofactor (AOB) is a mixture of commercially available fermented grain foods and has strong antioxidant activity. This study investigated the effect of AOB supplementation of standard rat food on markers of oxidative stress and inflammation in Otsuka Long-Evans Tokushima Fatty (OLETF) rats with type 2 diabetes. Blood glucose, hemoglobin A1c, plasma free fatty acid, triacylglycerol and plasminogen activator inhibitor-1 (PAI-1) were significantly higher in OLETF rats than in non-diabetic control Long-Evans Tokushima Otsuka (LETO) rats at 29 weeks. AOB (6.5% of diet) was given to rats during 29-33 weeks of diabetic phase in OLETF rats. OLETF rats with AOB supplementation showed decreased blood glucose, hemoglobin A1c, triacyglycerol, low density lipoprotein, cholesterol and PAI-1. Mitochondrial ROS production was significantly increased in heart, aorta, liver and renal artery of OLETF rats. Uncoupling protein 2 (UCP2) is known to regulate ROS production. We found aortic UCP2 protein expression increased in OLETF rats, and AOB returned UCP2 expression to normal. Aortic endothelial NO synthase (eNOS) was also increased in OLETF rats more than in LETO rats at 33 weeks. In contrast, phosphorylated vasodilator-stimulated phosphoprotein, an index of the NO-cGMP pathway, was significantly diminished. AOB increased eNOS proteins in LETO and OLETF rats. In conclusion, AOB significantly improved the NO-cGMP pathway via normalizing ROS generation in OLETF rats. The data suggest that dietary supplementation with AOB contributes to nutritional strategies for the prevention and treatment of type 2 diabetes mellitus.     

The Structure-Activity Relationships in Coronatine Analogs and Amino Compounds Derived from (+)-Coronafacic Acid

In order to investigate the active site of coronatine, the coronatine stereoisomers and analogs were synthesized by replacing the coronamic acid moiety with other amino compounds. The hypertrophy response of potato tubers was used for the bioassay of the compounds. A carboxyl group in coronamic acid was indispensable for the induction of activity. Moreover, the configuration at α-carbon atom in the amino acid was closely related to increase in activity Some alkyl groups of the amino acid also concerned with the activity.