LEC mutant rats exhibit an abnormal hepatic copper accumulation, due to the defection of the rat homologue of the Wilson's disease gene. In this study, we found a definitive evidence that the rat Wilson's disease gene of LEC rats was partially deleted at the 3' end of its protein-coding region, by performing Southern blot analysis. Furthermore, in Northern blot analysis, we confirmed that expression of the rat Wilson's disease gene was deficient in the liver of LEC rats. The partial deletion of the rat Wilson's disease gene should be responsible for the deficient expression of that gene in LEC rats.
An Escherichia coli pgsA null mutant deficient in acidic phospholipids shows a thermosensitive cell lysis phenotype because of activation of the Rcs phosphorelay signal transduction system. We conducted a DNA microarray analysis with special attention to the genes affected by growth temperature in the mutant deficient in acidic phospholipids. Among the genes identified as highly expressed at high temperature in the pgsA null mutant, the osmB gene was shown to be dependent on the Rcs system for the high expression by dot blot hybridization. Induction of the cloned osmB in the pgsA null mutant caused the thermosensitive defect even in the absence of the Rcs system. Although the deletion of osmB did not suppress the thermosensitivity in the presence of the Rcs system, indicating a multifactorial nature of the deleterious effect of the Rcs activation, we suggest that the osmB hyperexpression is one of the causes of the Rcs-dependent lysis phenotype of the pgsA null mutant.
A 59-year-old female with a previous history of head injury presented with mild occipitalgia due to dolichoectasia of the middle cerebral artery (MCA). Initial examination by computed tomography and angiography using the usual projections suggested a terminal internal carotid artery saccular aneurysm. However, angiography by the reverse Waters view excluded a saccular aneurysm. Superselective angiography using a microcatheter revealed the complex tortuous course of the MCA due to dolichoectasia. She was discharged and has remained asymptomatic. Superselective angiography is extremely useful for the diagnosis of dolichoectasia localized in the MCA.
The Escherichia coli pgsA3 mutation, which causes acidic-phospholipid deficiency, was found to repress the flagellar master operon, as assessed by the beta-galactosidase activities of flhD-lacZ fusions. This explained the impairment of flagellar formation and motility by the mutation. A series of deletion analysis indicated that a 40-bp region, at the 5' end of the flhD locus examined, was responsible for the repression of a downstream transcription initiation that was catabolite-repression sensitive. This novel regulatory region was 200 bp upstream of the first possible translation initiation site.
Platelet survival time was measured in 46 patients with various cardiovascular diseases and 5 healthy controls based upon ICSH criteria using 111Indium labeled platelets, and thrombus formation was investigated by scintiphotography. Platelet count, β-thromboglobulin and coagulation-fibrinolytic system were also investigated.Significant shortening of mean platelet survival time was observed in patients with arteriosclerosis obliterans and aortic aneurysm comparing with healthy controls. The same tendency was seen in patients with mitral stenosis who had a history of thromboembolism and in patients with left ventricular aneurysm due to myocardial infarction in spite of warfarin therapy.Correlations were necognized beween platelet survival time and platelet count and between platelet survival time and laboratory tests of coagulation-fibrinolytic system were not significant.The accumulation of labeled platelets on a thrombus in the left ventricular aneurysm in one patient and in the left atrium in two patients was clearly detected on the scintiphotogram. An accumulation of labeled platelets was detected on an aortic prosthetic graft, especially at the anastomotic sites and also on the thromboend-arterectomised segment in cares with arteriosclerosis obliterans.Imaging of accumulated platelets and measurment of platelet survival time using 111Indium-oxin labeled platelets was considered to be an useful tool for the diagnosis and the evaluation of treatment in cardiovascular disease.
A computational code has been developed to analyze the non-steady flow field of the thermal diffusion column in the higher pressure region. Numerical analyses for H2-HT are performed for the thermal diffusion column with an effective height of 1,500 mm, a hot wire of 0.15 mm and a cold wall of 15 mm in radius. In the condition that temperatures of cold wall and hot wire are 77.35 and 1,277.35 K at the pressure less than 0.112 MPa, the flow fields reach the steady state. However, a secondary circulation observed near the bottom of the column moves periodically at the pressure of 0.112 MPa or more. The frequency of the flow fields becomes larger as the gas pressure increases. The marginal pressure to make flow field apart from the steady state to the periodic state is predicted with the present analyses.
Three hereditary human disorders, Werner's syndrome, Bloom's syndrome and a subset of Rothmund-Thomson syndrome, are associated with the loss of function of the respective RecQ homologues BLM, WRN, and RTS. These RecQ homologues are composed of a conserved helicase domain flanking C- and N-terminal domains. In contrast to BLM, WRN, and RTS, another RecQ homologue, RECQ5, possesses only short N-terminal region preceding the helicase domain and a long unique C-terminal domain. Although no disease has yet been genetically linked to a mutation in RECQ5, the prominent roles of RecQ helicase in the maintenance of genome stability suggest that RECQ5 helicase is likely to be important in vivo. To acquire a better understanding of RECQ5 function, we investigated protein interaction with the C-terminal domain of Drosophila melanogaster RECQ5/QE. A portion of Drosophila melanogaster retrotransposon mdg3, which corresponds to a nucleocapsid protein (gag-NC), was identified by use of the yeast two-hybrid system as interacting specifically with it. Glutathione S-transferase (GST) pull down experiments indicated that the mdg3 gag-NC bound mainly to an acidic region in the C-terminal domain of RECQ5/QE, which is adjacent to the RecQ helicase domain. The helicase activity of RECQ5/QE was stimulated by mdg3 gag-NC protein in vitro. These data suggest that RECQ5/QE helicase interacts physically and functionally with mdg3 gag-NC through the acidic region and that RecQ homologue might be involved in retrotransposition and genomic stability.
