Search PubMed⌕ Search

Biomedical subjects

T Kurihara

Publications and source records attributed to T Kurihara.

At least 379 records · Page 21Linked to original sources
PubMed1979

Sigma subunit of Escherichia coli RNA polymerase affects the function of lambda N gene.

A new class of Escherichia coli mutants, referred to as grn, has been isolated by localized mutagenesis. These mutations affect the sigma subunit of DNA-dependent RNA polymerase (ribonucleoside 5'-triphosphate:RNA nucleotidyltransferase, EC 2.7.7.6) by abolishing the expression of the lambda N gene, and they are closely lniked to dnaG in the order dnaG-grn-uxaA. Detailed study of one such mutant, grn1, yielded the following results: (i) grn1 is a single mutation and the mutant cell shows cold-sensitivity in growth; (ii) the Grn phenotype of the mutant can easily be suppressed by secondary mutations in the beta subunit gene of RNA polymerase; (iii) purified holoenzyme of RNA polymerase isolated from the mutant showed an altered salt-dependency in vitro, and the mixed reconstitution of the mutant with the wild-type subunits showed that the sigma subunit of the grn1 mutant is altered; (iv) lambda phage mutants (lambda grg), which overcome the grn mutation, can be classified into two groups, the "nin-deletion" and the "N-mutant" groups (both of these are also able to grow on the previously described groN mutant of Georgopoulos and nusAB of Friedman); (iv) the mutant polymerase transcribed 12S as well as 7S RNA from lambda DNA in the presence of the rho factor in vitro. These results indicate that the grn mutation alters the sigma subunit of RNA polymerase and that the sigma subunit participates in activating the N-mediated antitermination mode of lambda phage transcription.

Bacteriophage lambda↗
PubMed1979

Exercise stress myocardial perfusion scintigraphy with thallium-201.

We performed exercise stress scintigraphy with thallium-201 in 88 patients including 31 patients of effort angina and nine patients of old myocardial infarction without angina. Sensitivity of exercise stress scintigraphy to detect effort angina was 77%, whereas sensitivity of exercise stress ECG was only 44.5%. The combination of stress scintigraphy with stress ECG enhanced sensitivity up to 87%. Exercise stress scintigraphy was useful particularly in cases with one vessel disease and those who failed to achieve sufficient exercise stress. Besides exercise stress scintigraphy did not show false positive response, differing from exercise stress ECG. Myocardial imaging is a method which shows the balance between myocardial perfusion demand and supply.

Adult↗
PubMed1978

Noninvasive cardiovascular findings in familial amyloid polyneuropathy.

The cardiovascular system was examined in 19 cases of familial amyloid polyneuropathy. In a group of patients with neurological involvement, various cardiac abnormalities were common, including orthostatic hypotension, prominent apex cardiographic A waves, abnormal apical systolic waves (bulges), systolic murmurs, mid-systolic clicks, QS waves, atrioventricular block, left bundlebranch block, and abnormalities of ejection time and pre-ejection period. Though there was one case with pronounced cardiac abnormality despite a normal neurological state, and though cardiovascular symptoms appeared later than neurological symptoms, the degree of cardiac involvement generally paralleled the severity of the neurological disorder.

Adult↗