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N Hashimoto

Publications and source records attributed to N Hashimoto.

At least 523 records · Page 29Linked to original sources
PubMed1990

[Magnetic resonance imaging of subarachnoid hemorrhage due to ruptured intracranial aneurysm].

We report MRI (magnetic resonance imaging) findings of 31 cases with subarachnoid hemorrhage (SAH) due to ruptured intracranial aneurysm. Among these cases, 25 were studied within 72 hours after onset of SAH. A resistive type MRI scanner operating at a field of 0.2 Tesla was used in obtaining inversion recovery (IR) and saturation recovery (SR) images. IR 1500/43/400 (T1 weighted image, T1W), SR 1000/60 (SR image) and SR 2000/100 (T2 weighted image, T2W) were chosen for analysis. The SR image was usually adopted and coronal and/or sagittal images were added when there was enough time for examination. Slice thickness was 10 mm and slice interval was 15 mm. The scan was not necessarily aimed at the visualization of aneurysm itself. 1) In the acute phase of SAH, subarachnoid spaces near the ruptured aneurysm were appeared as isointensity areas on T1W and as high intensity areas on SR image. In the subacute phase, they were depicted as high intensity areas on both T1W and SR images, and as high intensity areas on T2W. 2) Intraventricular hemorrhage was visualized as a niveau-like high intensity area, especially, within the posterior horns on the SR images. 3) SR and T2W images were suitable for detection of aneurysm itself. In a resistive-type scanner, small aneurysms were not easily visualized due to the lack of high resolution. However, 29% of aneuysms, which were not giant, could be visualized on MRI. 4) Identification of intracerebral hemorrhage and cerebral ischemia from various causes was easy on both T1W and T2W images.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[Blood glutathione in idiopathic nephrotic syndrome of childhood].

We studied blood glutathione in children with idiopathic nephrotic syndrome (INS). Plasma glutathione concentrations were significantly (p less than 0.02) lower in INS patients at relapses (0.37 +/- 0.29 microgram/ml, n = 21) than those in controls (0.62 +/- 0.36 microgram/ml, n = 22). As compared with patients with chronic glomerulonephritis (316.4 +/- 128.3, n = 8), the INS patients had lower blood glutathione concentrations (208.3 +/- 46.1 micrograms/ml, n = 6), although the difference was not statistically significant (p less than 0.10). The glutathione, mixed in the solutions containing plasma proteins or bovine serum albumin, showed sequential reductions of the concentration with time. There was no significant difference between the blood glutathione concentrations in the rats given glutathione containing water for 7 days and in those given distilled water. An inverse correlation was noted between blood glutathione and plasma cholesterol levels in the rats. From these results it may be concluded that INS patients have a decreased blood glutathione level, although the cause is unknown.

Adolescent↗
PubMed1990

[A case of right duplex kidney with double ureters and left dysplastic kidney with bifid ureter].

During dissecting practice for students, a case of anomalous urinary tracts was found in a 81 year-old Japanese female cadaver which had an extraordinarily large right kidney with double ureters and a dwarf left kidney with a bifid ureter. The histological investigation on the left kidney revealed the renal dysplasia including thyroid gland-like widening of urinary tubules and the hyperplasia of interstitium. No renal corpuscles were observed besides very few primitive ones. Two ureters originating from the left kidney united each other in the proximal portions and the united ureter ran down the normal pathway to the urinary bladder. The left ureter was thin and underdeveloped but the circular and the oblique musculature were distinguished in the distal three quarters of the ureter. The right large kidney was shown to be a duplex kidney. Both the upper and the lower poles were well-developed and histologically normal except the compensatory hypertrophy of the cortex obviously resulting from the dysplasia of the left kidney. The upper and the lower pole ureters draining the duplex kidney never crossed each other and entered the bladder through adjoining two ureterovesical junctions at the normal position. The possible embryological basis for these anomalies was discussed.

Aged↗
PubMed1989

Human diabetes associated with a deletion of the tyrosine kinase domain of the insulin receptor.

The insulin receptor has an intrinsic tyrosine kinase activity that is essential for signal transduction. A mutant insulin receptor gene lacking almost the entire kinase domain has been identified in an individual with type A insulin resistance and acanthosis nigricans. Insulin binding to the erythrocytes or cultured fibroblasts from this individual was normal. However receptor autophosphorylation and tyrosine kinase activity toward an exogenous substrate were reduced in partially purified insulin receptors from the proband's lymphocytes that had been transformed by Epstein-Barr virus. The insulin resistance associated with this mutated gene was inherited by the proband from her mother as an apparently autosomal dominant trait. Thus a deletion in one allele of the insulin receptor gene may be at least partly responsible for some instances of insulin-resistant diabetes.

Adolescent↗
PubMed1989

Effects of transcatheter arterial chemoembolization with oral chemotherapy on hepatic neoplasms.

An investigation was carried out into the effects of lipiodol-transcatheter arterial chemoembolization (L-TACE) therapy on hepatocellular carcinoma (HCC) and metastatic liver cancer, as well as the effects of oral 5-fluorouracil administration after L-TACE. For L-TACE, lipiodol mixed with adriamycin (doxorubicin) was injected through a catheter inserted into the tumor feeding artery and this was followed by embolization with a gelatin sponge. Twenty national hospitals throughout Japan participated in this multicenter co-operative open trial. A total of 102 patients became the subjects of study, including 75 HCC patients, 12 metastatic liver cancer patients treated with L-TACE, and 15 HCC patients who had hepatectomy after L-TACE. In 22% of the HCC patients and in 42% of the metastatic liver cancer patients, the tumor size was reduced by more than 50% after L-TACE. 73% of the 63 HCC patients showed a more than 50% reduction of the levels of serum alpha-fetoprotein. Although the survival rates of the HCC patients who had a hepatic resection were better than those who had not, there was no statistically significant difference between the survival rates of the HCC patients and those of the metastatic liver cancer patients treated with L-TACE. The survival rates of the HCC patients after L-TACE did not change as a result of oral 5-fluorouracil administration. It was therefore concluded that L-TACE is an effective way of treating both HCC patients and metastatic liver cancer patients, and that repeated L-TACE should be considered for some patients whose serum levels of alpha-fetoprotein rose again after L-TACE. Further follow-up studies will be needed to discover the effects of oral chemotherapy after L-TACE.

Administration, Oral↗
PubMed1989

Characteristics of passive immunity against hantavirus infection in rats.

The protective effects of passively administered antibodies against hantavirus infection were studied in newborn rats. Death as well as infection were completely prevented from intraperitoneal challenge of strain SR-11 (SR) (2 x 10(3) FFU, 10(2.1) LD50), in newborn rats which received 0.1 ml of anti-SR rat serum (neutralizing antibody titer, 1:640) 4 hr before the virus challenge. In these rats, no virus was detected in the peritoneal macrophages, lung, kidney, and brain. The immune serum infusion before the virus challenge also conferred protection to rats against an intramuscular or subcutaneous challenge of strain SR, but did not protect the rats against intracerebral challenge of the virus. In the rats which received the immune serum after the challenge, infection was not prevented, although some of the animals were protected from the death. Virus titers in the lung, kidney, and brain of the rats were reduced by the transfer of the immune serum even as late as 72 hr after the challenge. Cross-protection in the rats which received the immune serum was strong between strains SR and KI-262 within the same serotype, but very weak between strains SR and Hantaan 76-118 of different serotypes.

Animals↗
PubMed1989

Establishment of the experimental conditions for inducing saccular cerebral aneurysms in primates with special reference to hypertension.

To find out the optimum experimental conditions for the induction of saccular cerebral aneurysms in primates, various procedures for inducing renal hypertension were used in cynomolgus monkeys treated with ligation of unilateral carotid artery and beta-amino-propionitrile feeding. Animals were divided into four groups. In the first group, both kidneys were simultaneously compressed with a figure-eight ligation. In the second group, the kidneys were ligated at an interval of one week. In the third and fourth groups, posterior branches of both renal arteries were ligated at the same time, or at an interval of one week, respectively. Hypertension about 200 mmHg was produced only in the last group and aneurysms were noted in more than half of these hypertensive animals. The best procedure for renal hypertension to induce cerebral aneurysms was proved to be ligation of the posterior branches of both renal arteries at an interval of one week. We can conclude that lasting severe hypertension is essential for inducing cerebral aneurysms in monkeys.

Animals↗
PubMed1989

Effects of portacaval shunt, transposition, and dimethylnitrosamine-induced chronic liver injury on pancreatic hormones and amino acids in dog.

The effect of portacaval shunt on amino acid metabolism and pancreatic hormone secretion remains a subject of controversy. This might be due to the fact that shunt has two consequences; it shunts portal blood into the systemic circulation, and it causes hepatic parenchyma dysfunction by decreasing total hepatic blood flow. In order to see which one of these two is the more important factor, we created a model of portacaval transposition in dogs (PCT) causing portal systemic shunting without impairing hepatic blood flow and compared it with a model of hepatic dysfunction in dogs created by administering dimethylnitrosamine (DMNA). The dynamics of amino acid levels and pancreatic hormone secretion in the portal blood were investigated. DMNA dogs and dogs with a standard end-to-side portacaval shunt (Eck) showed elevated immunoreactive glucagon (IRG) levels and low immunoreactive insulin (IRI) levels in the portal blood as well as an amino acid imbalance, while values in PCT dogs were similar to those of controls. These data suggested that high IRG and low IRI in the portal blood and amino acid disturbances in the dogs with Eck shunts were due to hepatic parenchyma dysfunction, rather than to portal-systemic shunting.

Amino Acids↗
PubMed1989

Histopathological study of induced cerebral aneurysms in primates.

Experimental cerebral aneurysms in monkeys induced by treating them with unilateral carotid ligation, renal hypertension, and beta-aminopropionitrile feeding were studied macroscopically and with light microscopy. Macroscopically, 13 cerebral aneurysms were observed in six of seven monkeys. Microscopically, the elastic lamina and the media ended around the beginning of the aneurysms. The thin aneurysmal walls consisted of fibrous connective tissues. All findings were generally in accordance with spontaneous lesions in humans. The induced cerebral aneurysms in primates are thought to be a suitable experimental model to clarify the pathogenesis of the disease.

Aminopropionitrile↗
PubMed1989

Cathepsin B and L activities in gastric cancer tissue: correlation with histological findings.

Cathepsin B and L activities in cancerous and noncancerous mucosal tissues from 29 patients with gastric cancer were determined with a small amount of tissue homogenate. Both enzyme activities were significantly higher in cancerous tissues than in noncancerous tissues. The cathepsin B activity was higher with decreasing differentiation of the cancerous tissues, and also with increasing depth of invasion and metastasis to regional lymph nodes. Significantly high cathepsin B activity was observed in specimens of poorly differentiated adenocarcinomas, as well as in specimens from patients with extensive metastasis to n2 or n3 lymph nodes. These results suggest that high cathepsin B activity is characteristic of gastric cancer which invades and metastasizes. Therefore, in cases of marked elevation of cathepsin B activity in cancerous tissues, relatively extensive resection may be necessary to obtain a cure.

Adenocarcinoma↗
PubMed1989

Pustular dermatosis of the scalp associated with autoimmune diseases.

A 36-year-old woman visited our hospital with a five month history of persistent pustulation, crusting, and alopecia on the vertex of the scalp. No pathological organisms were isolated from the lesions. Histological examination revealed non-specific changes of chronic inflammation with destroyed follicles. Antibiotic therapy produced no response, but steroid therapy was effective. From these observations, a diagnosis of erosive pustular dermatosis of the scalp (EPDS), as described by Pye et al., was made. The patient also had Hashimoto's thyroiditis, autoimmune hepatitis, and Takayasu's aortitis. The laboratory studies revealed an increased erythrocyte sedimentation rate, C-reactive protein 3+, hypergammaglobulinemia, and various auto-antibodies, suggesting the possibility of a pathogenesis common to both this dermatosis and the autoimmune diseases.

Adult↗
PubMed1989

Comparison of virulence between two strains of Rattus serotype hemorrhagic fever with renal syndrome (HFRS) virus in newborn rats.

Two strains of hemorrhagic fever with renal syndrome (HFRS) virus from Rattus, SR-11 and KI-262, showed virtually identical antigenicity but differed from prototype strain Hantaan 76-118 (Apodemus origin) in a neutralization test. Wistar newborn rats inoculated intraperitoneally (i.p.) with SR-11, which was isolated from a laboratory rat associated with an outbreak of HFRS, developed clinical signs such as ataxia and limb paralysis and died at about 18 days after inoculation. The LD50 of SR-11 in 1-day-old rats was 10(1.2) focus-forming units (FFU). In contrast, the animals inoculated i.p. or intracerebrally with 10(4) FFU of KI-262, which was from a wild rat in a dumping-ground area--an enzootic focus where no human cases have been recorded--did not show any significant clinical signs. The susceptibility of rats to SR-11 fatal infection was age-dependent. Virus titers in brains, lungs, kidneys, and livers of the rats inoculated with SR-11 were significantly higher than those in the same organs of the animals infected with KI-262. Necrosis of neurons in the brain tissue occurred in the rats infected with SR-11, while it was mild in the animals infected with KI-262.

Aging↗
PubMed1989

Malignant luteoma in a sow.

A case of malignant luteoma was found in a 3-year-old Landrace sow. A large neoplastic mass was present in the left ovary and small neoplastic nodules were seen in the right ovary. There were metastatic lesions in the diaphragmatic peritoneum and heart. The neoplastic cells were extremely pleomorphic and among them relatively large cells predominated. The neoplastic cells had lipid droplets, membranous structures, intermediate filaments and lipofuscin granules in their cytoplasm.

Animals↗
PubMed1989

Sensitivity of arterial baroreflex changes during daily activity.

1. Continuous ambulatory arterial pressure monitoring was performed by telemetry in 34 hypertensive and four normotensive subjects and arterial baroreflex sensitivity was evaluated by computer analysis of pulse wave. Three consecutive pulses were selected, on two criteria, from the 24 h recording: (i) progressive and linear increase or decrease in systolic arterial pressure and heart period, (ii) change of systolic arterial pressure in three pulses exceeds a threshold value. The systolic arterial pressure and heart period of three pulses were averaged and the slopes of systolic arterial pressure and heart period were calculated as baroreflex sensitivity. 2. When the threshold value was set to 5 mmHg, baroreflex sensitivity measured by the present method correlated with baroreflex sensitivity as measured by the phenylephrine method (r = 0.667, P less than 0.001). 3. The baroreflex sensitivity from the pressor-bradycardia and the depressor-tachycardia reflex decreased as threshold value was increased from 3 to 4 mmHg to over 20 mmHg. With the pressor-bradycardia reflex, the initial systolic arterial pressure of three pulses did not change, but the initial heart period shortened progressively as the threshold increased. With the depressor-tachycardia reflex, the initial systolic arterial pressure increased and the initial heart period shortened progressively. This suggests that the sensitivity of arterial baroreflex changes dynamically according to input of reflex are during daily activity.

Adult↗
PubMed1989

The influence of gonadal function and the effect of gonadal suppression treatment on final height in growth hormone (GH)-treated GH-deficient children.

One hundred and sixty-one children with idiopathic GH deficiency who received GH treatment were followed until they reached their final height. Final height was found to be influenced by gonadal function. In 108 patients who had spontaneous puberty (91 boys and 17 girls; group A), the mean final height was 151.8 +/- 6.6 (+/- SD) cm in boys and 141.7 +/- 7.4 cm in girls. In 29 patients with combined GH and gonadotropin deficiency (23 boys and 6 girls; group C), whose pubertal development was induced artificially at age 19.5 +/- 2.1 yr in the boys and 18.6 +/- 1.8 yr in the girls, the mean final height was 163.7 +/- 3.9 cm in boys and 151.0 +/- 5.1 cm in girls. The differences in final height between groups A and C were significant in both boys and girls. The shorter final height in group A was caused by the shorter pubertal duration and smaller pubertal height gain than those in normal children. In 24 patients (17 boys and 7 girls; group B) who developed early signs of puberty, gonadal suppression therapy with cyproterone acetate and/or medroxyprogesterone acetate was given. The mean SD score of the final height in these 24 patients was -2.1 +/- 0.6, significantly higher than that in group A. This beneficial effect of gonadal suppression treatment on final height was caused by increases in the duration of puberty and the pubertal height gain.

Adolescent↗
PubMed1989

An ultrastructural study of malignant mesotheliomas in two cows.

Malignant mesotheliomas of two Holstein cows were examined by light and electron microscopy. These tumours were derived from peritoneal surfaces and were of biphasic type composed of mesothelial lining cells and submesothelial mesenchymal cells. Ultrastructurally, the neoplastic mesothelial cells were characterized by intermediate filaments, microvilli, desmosomes, tight junctions and basal laminae. The neoplastic submesothelial cells were closely associated with collagen filaments and some cells had several resemblance to the neoplastic mesothelial cells. The ultrastructural features of the mesotheliomas are discussed in comparison with those of adenocarcinomas and fibroblastic neoplasms. In one case of malignant granulosa cell tumour involved the left ovary and its morphology was apparently different from that of the mesothelioma. Multiple primary tumours are uncommon in cattle.

Animals↗
PubMed1989

Mosquito collection in endemic areas of Japanese encephalitis in Hokkaido, Japan.

A study was conducted during 1985 and 1986 to evaluate the roles of mosquito species as possible vectors of Japanese encephalitis (JE) virus in Hokkaido. The number of Culex tritaeniorhynchus was very low among the four pig farms where outbreaks of abortion caused by JE virus were observed in swine populations. At one farm near Sapporo, only one Cx. tritaeniorhynchus was found among a total of 510 mosquitoes collected during the survey period from July to October 1985, even when JE virus activity among sentinel pigs was revealed by seroconversion. At another farm in the south, no individuals of this mosquito species were found among 987 mosquitoes collected at the time of the outbreaks of abortion. Cx. pipiens pallens, Anopheles species, Aedes vexans nipponii, and Ae. japonicus were predominant over Cx. tritaeniorhynchus. Cx. tritaeniorhynchus, almost a solve vector species of JE virus in the southern part of Japan, is probably not a vector of the virus in Hokkaido. The collected mosquitoes (2,332 from 1985 and 1,403 from 1986) were processed for virus isolation but no JE virus was isolated. More extensive field studies are necessary to provide further information on the role of mosquito species other than Cx. tritaeniorhynchus in the transmission of JE virus in the northern limits of its range including Hokkaido.

Abortion, Veterinary↗