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Biomedical subjects

N Shimada

Publications and source records attributed to N Shimada.

At least 163 records · Page 9Linked to original sources

MR appearance of the persistent hypoglossal artery.

We describe the MR appearance of the persistent hypoglossal artery incidentally found in a case of known glioblastoma multiforme. On the spin-echo images, an abnormal tubular structure of low intensity penetrating the hypoglossal canal was recognized. MR angiography showed its vascular nature and the anomalous vessel connecting the internal carotid and basilar arteries.

Arteries↗

[A Japanese family with congenital abnormal plasminogen].

A Japanese family with congenital abnormal plasminogen is reported. The patient was a 44-year-old male with no past history of thrombosis. Since only the plasminogen (PLG) activity was reduced on laboratory tests before surgery for lumbar disc herniation, coagulation and fibrinolysis studies were performed in the patient and his family. The patient underwent resection of the nucleus pulposus and posteriorlateral fixation of the lumbar spine. The PLG activity was 8% in the patient and his sister, 55% in his father, and 53% and 48% in his nephew brothers. The PLG antigen level was normal in all members of his family examined. IEF of PLG antigen showed abnormal patterns in which all bands were shifted slightly to the cathode side in the patient and his sister, but his father and nephew brothers exhibited duplicated bands showing combinations of normal and abnormal patterns. From these results, the proband and his sister were considered to be homozygotes, and his father and nephew brothers to be heterozygotes for congenital abnormal plasminogen. Acute reactant substances (fibrinogen, CRP, CPK, C1IN, alpha 1AT, etc.) and PIC (plasmin, alpha 2-plasmin inhibitor complex) increased after the operation due to the surgical insult, but the surgery did not trigger thrombosis. This patient is considered not to have developed thrombosis although he was a homozygote for congenital abnormal plasminogen, because the anticoagulation process until thrombogenesis was normal.

Adult↗

[Cost benefit analysis of care of low-birth-weight infants].

A model for cost-benefit analysis of medical care of low-birth-weight infants was proposed in order to evaluate its economic efficiency using the notion of an expected value, routinely used in economics. The expected cost and benefit when a low-birth-weight infant is born were calculated and compared. Cost includes the hospital charges and the charges for long-term care of a handicapped survivor. Benefit includes the present value of lifetime earnings. Benefit/Cost Ratio was selected as a criterion to determine efficiency, with values exceeding 1 representing the case where the expected benefit exceeds the expected cost, meaning a net economic gain. Actual values were substituted in the model for cost-benefit analysis of care of very-low-birth-weight infants. Benefit/Cost Ratios corresponding to various birth weights were calculated, and the break-even point was found to be about 800 g, which was consistent with several former reports. However sensitivity analysis indicated that Benefit/Cost Ratio was affected greatly when either the discount rate or charges for long-term care of a handicapped survivor was changed. A net economic loss would be attributable to the higher incidence of sequela corresponding to very-low-birth-weight, which would suggest that to enhance economic gain investment in care for increasing the rate of intact survivals is essential. Further study is required to define adequate values, and to determine the grade of handicap as well as lifetime earnings.

Cost-Benefit Analysis↗

Periodontal conditions in older age cohorts aged 65 years and older in Japan, measured by CPITN and loss of attachment.

Periodontal conditions were assessed by CPITN and loss of attachment in 601 elderly people randomly selected in Kitakyushu, Japan. The percentage of edentulous persons was 21 per cent, 38 per cent and 65 per cent in the 65-74 year, 75-84 year and 85 years and older groups, respectively. In dentate persons, over 60 per cent had pocket probing depths of 4mm or more; in the majority loss of attachment did not exceed 5mm. The mean numbers of sextants with pocket probing depths of 4-5mm (CPITN 3) and probing depths of 6mm and more (CPITN 4) were similar in each age group. The mean numbers of sextants with both pockets and loss of attachment showed no clear difference among groups. Only the mean number of excluded (no, or only one tooth) sextants increased with increasing age from 1.9 to 3.1. It could therefore be suggested that in the population examined the progress of periodontal destruction with increasing age might not be shown by an increase in pocket probing depth, loss of attachment or gingival recession, but only by an increase in tooth loss. The results for the remaining teeth show that a) severe loss of periodontal attachment (6mm or more) was not frequently encountered, b) recession (attachment loss without pocketing) was present at only very low levels, c) the main periodontal problem seemed to be pocketing, which could be treated. It is therefore tempting to suggest that some of the teeth already lost, could have been saved if proper self- and professional care had been applied.

Aged↗

Increased expression of nucleoside diphosphate kinases/nm23 in human diploid fibroblasts transformed by SV40 large T antigen or 60Co irradiation.

When the expression levels of nucleoside diphosphate (NDP) kinase/nm23 were examined in four human normal diploid fibroblast cell lines in comparison with their corresponding immortalized cells transformed by SV40 large T antigen or 60Co irradiation, mRNA levels of the two isoforms (NDP kinase A/nm23-H1, NDP kinase B/nm23-H2) were increased in the immortalized cell lines. The increase was found to be associated with increased translation products. Furthermore, the cell extracts prepared from these immortalized cell lines demonstrated slightly higher enzyme activity than those from their normal counterparts. Neither the growth state nor the in vitro aging largely affected their expression in a normal cell line (TIG-3) examined. The results suggest possible involvement of NDP kinases/nm23 in acquiring an infinite growth property of these cells.

Antigens, Polyomavirus Transforming↗

Recombinant rat nucleoside diphosphate kinase isoforms (alpha and beta): purification, properties and application to immunological detection of native isoforms in rat tissues.

We previously demonstrated that at least two isoforms of nucleoside diphosphate (NDP) kinase, the products of two different tandemly arrayed genes, are present in rat. To understand the physiological role of each isoform, some biochemical properties of recombinant rat NDP kinase alpha- and beta-isoforms, produced in large amount, were studied. cDNAs of the two isoforms were inserted in an expression vector pET3b and recombinant enzymes were overproduced in Escherichia coli. Their primary structures were different from the native enzymes in that the latter suffer from modification of the NH2-terminal end. The two recombinant isoforms were purified from the cell lysate to apparent homogeneity by ammonium sulfate fractionation followed by three successive column chromatographies. Despite their extreme similarity in the amino-acid sequences, the two showed somewhat different enzymic properties in terms of di- and triphosphate nucleotide substrate specificity. They showed similar mobilities on SDS-PAGE as expected from their calculated molecular weight (alpha-isoform, 17,283 versus beta-isoform, 17,192) but differed in isoelectric point (alpha-isoform, pI 6.7; beta-isoform, pI 7.8) and heat stability. Polyclonal antibody which reacted with both isoforms and alpha-isoform-specific monoclonal antibodies differentially recognized native enzymes from rat tissues after the tissue extracts were separated by isoelectric focusing gel electrophoresis under a denaturation condition. The results showed that the alpha-isoform, though its amount varied from one tissue to another, was the major form in rat tissues examined compared with the beta-isoform which was detectable in brain and testis. There was no preference in their subcellular localization when examined with myelin, synaptosomal supernatant and total homogenate fractions from the rat cerebrum and cerebellum.

Amino Acid Sequence↗

Age-related changes of the myelinated fibers in the human corticospinal tract: a quantitative analysis.

A quantitative analysis was made of the myelinated fibers in the lateral corticospinal tract (LCST) at the levels of the 6th cervical, 7th thoracic and 4th lumbar spinal segments in 20 patients between 19 and 90 years old, and who died of non-neurological diseases. The diameter frequency histograms of myelinated fibers of LCST showed a bimodal pattern with a sharp peak of the small myelinated fibers and broad slope of the large myelinated fibers. The ratio of small fiber to large fiber densities was significantly higher in the 6th cervical (P < 0.05) and 4th lumbar segments (P < 0.01) than in the 7th thoracic segments. The density of small myelinated fibers was significantly lowered with advancing age (P < 0.05-0.001), while that of large myelinated fibers was not significantly decreased in the aged patients, although it showed a slight age-dependent declining tendency. Age-dependent decline of small fiber density was more prominent in the cervical and lumbar segments. Retraction of the axon-collaterals from large-diameter myelinated fibers, which are abundant in the cervical and lumbar segments, may contribute to the age-related diminution of the small myelinated fibers in the LCST.

Adult↗

Pironetin, a novel plant growth regulator produced by Streptomyces sp. NK10958. I. Taxonomy, production, isolation and preliminary characterization.

A novel plant growth regulator, pironetin, was isolated from the culture broth of Streptomyces sp. NK10958. It was extracted from the culture broth with ethyl acetate and purified by column chromatographies. Pironetin showed 23% inhibition on the growth of rice plants without any loss of crop yield at 10 g/a on 9 days before heading.

Crystallography, X-Ray↗

Pironetin, a novel plant growth regulator produced by Streptomyces sp. NK10958. II. Structural elucidation.

A novel plant growth regulator, pironetin was isolated from the culture broth of Streptomyces sp. NK10958. The structure of pironetin was determined to be (5R,6R)-5-ethyl- 5,6-dihydro-6-[(E)-(2R,3S,4R,5S)-2-hydroxy-4-methoxy-3,5-dimethyl-7- nonenyl]-2H-pyran-2-one by FAB-MS, 1H and 13C NMR, COSY, COLOC, DEPT, IR, X-ray crystallographic analyses and adapted Mosher's method.

Crystallography, X-Ray↗

[The etiology of peptic ulceration in patients with chronic pulmonary emphysema].

The purpose of this study was to determine the etiology of peptic ulceration in patients with pulmonary emphysema. We performed endoscopy in 50 patients with chronic pulmonary emphysema, these were patients with and without peptic ulcer. There was no significant differences between the patients with and without ulcer, with respect to past history of pneumonia, degree of dyspnea, current drugs, nutritional status, the extent of gastric mucosal atrophy, gastric mucosal blood flow, gastric mucosal hexosamine content and serum pepsinogen levels. But patients with peptic ulcer were significantly younger than patients without peptic ulcer. Cigarettes per day in patients with peptic ulcer 29.3 +/- 11.6 cigarettes/day were significantly higher than those without peptic ulcer 22.5 +/- 10.0 cigarettes/day. We concluded that increased incidence of peptic ulceration in patients with chronic pulmonary emphysema is related to the quantity of cigarette smoking.

Aged↗

[Chronological changes in MR imaging of inferior olivary pseudohypertrophy--report of two cases].

Olivary pseudohypertrophy (OH) and its chronological change was examined by MR images in two patients with brainstem vascular disease. Patient 1 was a 63-year-old woman who developed an infarction in the red nuclei associated with "top of the basilar" syndrome. Two months later, she showed 2-4 c/s rhythmic myoclonus (rubral tremor) involving four extremities. Palatal myoclonus was absent. MR images of the inferior olives did not demonstrate a significant lesion in 10 days after the onset, but showed OH in 6 months, and then their size attained a maximum in 10 months after. On T2-weighted (T2) images and proton-density-weighted (PD) images obtained at 20 and 24 months, OH gradually became irregular but discrete in their intensity, and the intensity had also decreased to some extent. Rhythmic myoclonus had subsided to some extent after 20 to 24 months. Patient 2 was a 62-year-old woman who had a small hemorrhage in the pontine tegmentum. She developed 2.5 c/s vertical ocular myoclonus without palatal myoclonus two months after the onset. MR images showed OH in 6 and 8 months after the onset. On T2 and PD images obtained at 20 months, the image of OH gradually developed to become irregular in intensity and slightly atrophic in size. The ocular myoclonus somewhat reduced in their intensity 12 months after the onset. These serial changes in MR images were considered to correspond to the chronological changes of the pathology of OH. Appearance and subsidence of the myoclonic movement was also considered to correlate to the sequential changes of MR images of OH.

Cerebrovascular Disorders↗

[Classification of hyperlipidemia in a worksite population in Japan using criteria of the U.S. National Cholesterol Education Program].

Hyperlipidemia is an important risk factor of arteriosclerotic diseases. In Japan, as heart disease and cerebrovascular disorders rank second and third as the causes of death, demand has intensified for measures to prevent these diseases. In the U.S., the National Cholesterol Education Program (NCEP) was initiated as a means to prevent CHD by reducing th prevalence of hypercholesterolemia. Since 1988, this program has demonstrated effectiveness in this regard. In Japan, there are no consistent guidelines for the management of hyperlipidemia such as are espoused by the NCEP. In this study, in an endeavor to resolve this problem, a worksite population (1343 adult males) was classified according to the NCEP guidelines and the role and effectiveness of NCEP in this population were studied. A questionnaire concerning life-style and some biochemical findings were also used to classify the subjects according to the NCEP guidelines. Of the subjects, 22.8% were classified as hypercholesterolemic (> or = 240 mg/dl) and another 34.9% as being borderline high risk (> or = 200 < 240 mg/dl). Twenty-five percent of subjects required diet or drug therapy. The percentage of subjects requiring therapeutic intervention increased with age. The therapy group subjects tended to have a larger number of risk factors compared to the normal group. They also featured a significantly high age-adjusted odds ratios for hypertension, diabetes mellitus, obesity, and elevated serum triglyceride. This study suggests that in the health management of those in the therapy group, educational instruction on coronary risk factors is required.

Adult↗