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Biomedical subjects

S Katayama

Publications and source records attributed to S Katayama.

At least 271 records · Page 15Linked to original sources
PubMed1993

Effects of captopril or nitrendipine on left ventricular collagen or laminin B2 gene expression.

A study was designed to clarify the effects of captopril (CAP) or nitrendipine (NITR) on cardiac hypertrophy and left ventricular expression of the laminin B2 or collagen (COL) gene in spontaneously hypertensive rats (SHRs). Cardiac weight was significantly increased in 20-week-old SHRs. Gene expression of the alpha 1 chain of type IV COL determined by northern blot analysis decreased with age in Wistar-Kyoto rats and SHRs. Left ventricular laminin B2 mRNA was decreased at 12 weeks and increased again at 20 weeks in both strains. Daily oral administration of CAP (40 mg/kg, n = 5) or NITR (30 mg/kg, n = 4) to SHRs from 8 to 20 weeks decreased blood pressure to 142 mmHg (p < 0.01 vs 197 mmHg in controls, n = 5). Cardiac weight was 1.26 +/- 0.04 (SE) g in controls and was reduced to 1.03 +/- 0.05 g (p < 0.01) by CAP, but not by NITR (1.24 +/- 0.04). Left ventricular laminin B2 gene expression was attenuated by CAP and NITR to 41% and 32% of the control value, respectively. CAP significantly decreased left ventricular alpha 1 type IV COL mRNA to 11% of the control level, whereas NITR caused a reduction only to 75%. CAP also decreased alpha 1 or alpha 2 type I COL mRNA. These results suggest that angiotensin converting enzyme inhibitors prevent and/or cause regression of cardiac hypertrophy by inhibiting the gene expression of extracellular matrix, and that angiotensin II may have a pivotal role in cardiac hypertrophy.

Animals↗
PubMed1993

Astrocytic gliomas: MRI and pathological grade.

The relationship between MR configuration and pathological grade was studied in 41 histologically verified supratentorial astrocytic gliomas with a 0.5T superconductive MR system. The gliomas included 13 low-grade astrocytomas (LGAs), 14 anaplastic astrocytomas (AAs) and 14 glioblastoma multiformes (GBMs). MRI configurations were classified into nine criteria which were scored and statistically analyzed. The mean values of LGAs, AAs and GBMs were 0.45 +/- 0.31, 1.18 +/- 0.20 and 1.47 +/- 0.22. In each grade, MRI score increased as pathological grades increased (p < 0.01-0.001). LGAs had significantly lower values than AAs in five of the nine criteria (55.6%); heterogeneity, cyst or necrosis, edema or mass effect, border definition, and the degree of contrast enhancement, and lower values than GBMs in eight criteria (88.9%) except for hemorrhage. Three criteria (33.3%), heterogeneity, cyst or necrosis, and flow void sign were significantly higher in GBMs than AAs. The four variables, heterogeneity, cyst or necrosis, edema or mass effect and border definition, proved to be important factors related to the pathological grade in a multiple regression analysis.

Adolescent↗
PubMed1993

Quantitative measurement of normal and hydrocephalic cerebrospinal fluid flow using phase contrast cine MR imaging.

Measurements of the cerebrospinal fluid (CSF) flow using phase contrast cine magnetic resonance (MR) imaging were performed on a phantom, 12 normal subjects and 20 patients with normal pressure hydrocephalus (NPH). The phantom study demonstrated the applicability of phase contrast in quantitative measurement of the slow flow. The CSF flows of the normal subjects showed a consistent pattern with a to-and-fro movement of the flow in the anterior subarachnoid space at the C2/3 level, and they were dependent on the cardiac cycle in all subjects. However, the patients with NPH showed variable patterns of the CSF pulsatile flow and these patterns could be divided into four types according to velocity and amplitude. The amplitudes of each type were as follows: type 0 (n = 1), 87.6mm; type I (n = 2), 58.2mm (mean); type II (n = 6), 48.0 +/- 5.0mm (mean +/- SEM); and type III (n = 11), 19.9 +/- 1.8mm (mean +/- SEM). The decrease of the amplitudes correlated to a worsening of the clinical symptoms. After the shunting operation, the amplitude of to-and-fro movement of the CSF increased again in the patients with NPH who improved clinically. Some of the type III cases were reclassified type II, I and 0 and also one of the type II cases changed type I after the shunting operation. We conclude that the phase contrast cine MR imaging is a practically and clinically applicable technique for the quantitative measurement of the CSF flow.

Adolescent↗
PubMed1993

[Sleep-disordered breathing in Japan: an overview].

Questionnaires were answered by 3,243 presumably healthy subjects who underwent regular medical checkups in four cities. The prevalences of risk factors for sleep-disordered breathing (SDB) were as follows; habitual snoring was reported by 13-16%, excessive daytime sleepiness by 8-9%, insomnia by 7-13% and systemic hypertension by 5-13%. Polysomnographic studies performed on some possible SDB cases who were selected by the presence of risk factors estimated that the average prevalence of SDB in the present population would be in the range of 1.14-1.94%. Secondly, questionnaires were sent to the main hospitals and institutes involved in the management of patients with SDB, asking about diagnostic criteria, number of SDB patients, management, effectiveness of treatment, etc. The total number of patients registered at those hospitals was 2,751 in 1991. Of the 132 patients who were followed for more than six months, the efficacies of body weight loss, medications, nasal CPAP and UPPP were compared. Based on the analyses of the 279 patients examined some tentative vriteria for diagnosis and for treatment are proposed.

Female↗
PubMed1993

The occurrence of monocytoid B-lymphocytes in autoimmune disorders.

Occurrence of monocytoid B-lymphocytes (MBL) in extranodal organs in various inflammatory diseases was examined. MBL were present in 5 (11.4%) of 44 patients with Graves' disease, 11 (36.7%) of 30 with Hashimoto's thyroiditis, 1 (8.3%) of 12 with lymphoid follicular hyperplasia (LFH) of stomach, 1 (10%) of 10 with cutaneous LFH, and 0 of 5 with LFH of lung. The MBL presented as irregularly shaped nodular collections of cells, directly surrounding secondary follicles. Immunohistochemistry revealed a B-cell nature of these cells which expressed the following antigens; CD3-, CD 15-, CD45RA+, CD45Ro-, CDw 75+, CD74+, Mx-PanB+, MB-1+, EMA-. There were no immunoglobulin light chain restriction among infiltrating lymphoid cells. MBL in 2 of 18 cases showed positive reaction for CD43. The patients with MBL were older than those without MBL in each organ site, though the difference was not statistically significant. These findings showed that the MBL could appear in nonlymphoid organs affected by long-standing inflammation. High frequency of the appearance of the MBL in Hashimoto's thyroiditis suggest that MBL proliferation correlates with an impaired immune status.

Adult↗
PubMed1993

[Bone changes in Parkinson's disease].

Parkinson's disease (PD) is a movement disorder and tends to occur in elderly people, who sometimes develop age-related osteoporosis. Pathological bone changes seem to affect the outcome and prognosis of PD. We studied the relationship between bone changes and PD. Bone examination was conducted by multiple scanning X-ray photodensitometry in 70 patients with PD and 46 age-matched controls. We then compared the results with the clinical characteristics of PD. Of the 70 patients, 44 were women and 26 were men; the mean ages were 65.5 +/- 7.9 (mean +/- SD) and 63.4 +/- 9.9 years, respectively. Of the 46 controls, 25 were women and 21 were men, with mean ages of 61.4 +/- 10.2 and 60.3 +/- 9.3 years, respectively. Osteopenia was detected in 26 (59%) of the 44 female, and 5 (19%) of the 26 male patients, and in 6 (24%) of the 25 female and 2 (9%) of the 21 male controls. The frequency of osteopenia was significantly greater in the female patients than in the male patients or the female controls. The mean Hoehn & Yahr stage of female patients with osteopenia was more severe than that of those without osteopenia, with a significant difference between the two groups. Osteopenia in men was related to the duration of PD, but this was not so in the women. The female patients without osteopenia tended to have earlier onset of PD and longer duration of the disease and treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1993

[Mutagenicity of the gastric juice in chronic gastritis].

Mutagenicity of the gastric juice in patients with chronic gastritis was determined by reverse mutation test using Salmonella typhimurium TA100 and investigated the relationship between intestinal metaplasia which has been regarded as a precancerous lesion (candidate) of gastric cancer, and atrophy of gastric mucosa. The degree of intestinal metaplasia was quantified in six biopsy specimen for one patient and represented as metaplasia index (MI). The Ames ratio, mutagenicity, of gastric juice showed no significant relationship with the age of patient. On the other hand, Ames ratio and MI, and the age of patient showed significant relationship, respectively (p < 0.01). Furthermore, patients with more intensive atrophy tended to show higher Ames ratio. As shown above, mutagenicity of the gastric juice suggested some relationships to the development of intestinal metaplasia and atrophy of gastric mucosa.

Chronic Disease↗
PubMed1993

[A case of sodium bromate intoxication with cerebral lesion].

We confirmed a cerebral lesion due to sodium bromate intoxication on MRI, SPECT, auditory brainstem response (ABR) and sensory evoked potential (SEP). The patient was 34 years old, and ingested sodium bromate (14 g) to commit suicide. Vomiting, epigastralgia, watery diarrhea and anuria appeared after 30 minutes and he became deaf within 12 hours. Renal function recovered after hemodialysis. Renal biopsy revealed acute renal tubular necrosis. After one month, burning pain appeared in bilateral lower extremities. Sporadic, clear and small high intensity spots were observed in the deep white matter of the right occipitotemporal border zone and bilateral centrum semiovale on T2 and proton weighted images of brain MRI. IMP-SPECT disclosed partial low perfusion in the left parietal gray matter. Central conduction time was delayed on ABR and SEP. The clinical symptoms and course together with laboratory studies suggest that the cerebral lesion was due to direct sodium bromate intoxication.

Adult↗
PubMed1993

[Coagulation and fibrinolytic parameters in patients with various angiopathies--analysis in cerebral thrombosis, diabetic and vasculitic neuropathies].

We measured the coagulation and fibrinolytic parameters in patients with various angiopathies to clarify the usefulness of the parameters for the evaluation of vascular involvement. The study included 65 patients with cerebral thrombosis at the chronic stage, 47 diabetics with neuropathy associated with diabetic microangiopathy, 15 diabetics without neuropathy, and 16 patients with vasculitic neuropathy associated with collagen diseases. Control subjects were 45 patients with other neurological disorders without symptomatic angiopathies. In cerebral thrombosis at the chronic stage, the coagulation factor VIII (FVIII), von Willebrand factor (vWF), and platelet factor IV were elevated significantly as compared with age-matched controls. Diabetics with neuropathy showed significantly elevated FVIII and vWF in comparison with diabetics without neuropathy and controls. No significant difference in parameters concerning glucose metabolism was observed between the two groups of diabetics. These findings suggest that elevated activities of the coagulation parameters reflect not merely the abnormalities in glucose metabolism but also the presence of microangiopathy which causes diabetic neuropathy. The patients with vasculitic neuropathy exhibited significantly elevated FVIII, vWF and fibrin/fibrinogen degradation products (FDP). The present study demonstrated that FVIII and vWF are useful parameters for the evaluation of the extent of vascular involvement in angiopathies of different etiologies. It is important for the treatment of patients with the angiopathies, to monitor the coagulation parameters which reflect vascular involvement in addition to parameters for the disease activity.

Aged↗
PubMed1993

[Lymphoscintigraphy with 99mTc-DTPA-HSA in the diagnosis of protein-losing gastroenteropathy].

We evaluated the diagnostic capability of technetium-99m-diethylene triamine pentaacetic acid-human serum albumin (99mTc-DTPA-HSA) lymphoscintigrapy in a patient with protein-losing gastroenteropathy. 99mTc-DTPA-HSA (total 740 MBq) was injected subcutaneously into the digital webs of the both feet. With a gamma camera, whole-body and abdominal lymphoscintigrams were obtained after the injection of the radioisotope: early images and delayed images taken 5-15 min and 50-60 min, respectively, after the injection. A few days later, the dynamic lymphoscintigraphy was also performed. Lymph fluid leakage into the small bowel and the sites of the leakage were detected. It was concluded that lymphoscintigraphy with 99mTc-DTPA-HSA was a useful diagnostic tool in patients with protein-losing gastroenteropathy.

Adult↗
PubMed1993

[A case of chronic recurrent pulmonary embolism complicated with effort angina pectoris].

A 50-year-old man was admitted to our hospital because of shortness of breath and an oppressive feeling in his chest on exertion. As a result of examinations including pulmonary-angiography, pulmonary perfusion scan and phlebogram, we diagnosed the case as chronic recurrent pulmonary embolism due to deep vein thrombosis. Later on, the patient showed an abnormal reaction on treadmill exercise test, and revealed redistribution at the anteroseptal and the inferior wall on thallium exercise test. We performed coronary angiography and diagnosed the case as angina pectoris (seg. 1 was total occlusion, segs. 2 and 3 were filled with bridge collateral, seg. 7 was 75% stenotic lesion). We evaluated the acute effect of vasodilators on pulmonary and systemic hemodynamics. The effect was beneficial in that it improved the hemodynamics. On account of this we thought a reversible condition was presented, and we administered these drugs to this patient.

Angina Pectoris↗
PubMed1992

Regulation of flagellar motility by temperature-dependent phosphorylation of a 43 kDa axonemal protein in fowl spermatozoa.

Phosphorylation of fowl sperm proteins was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) after incubating the demembranated spermatozoa with [gamma-32P]ATP at 30 degrees C or 40 degrees C. A marked difference of phosphorylation between 30 degrees C and 40 degrees C was observed in a 43 kDa protein. This protein was slightly phosphorylated at 40 degrees C, but strongly phosphorylated at 30 degrees C in a cAMP-independent manner. The motility of demembranated spermatozoa was negligible at 40 degrees C, but vigorous movement was observed at 30 degrees C. These results showed that phosphorylation of a 43 kDa protein is likely to be a regulatory step in the maintenance of fowl sperm motility.

Animals↗
PubMed1992

Preferential consumption of heparin cofactor II in disseminated intravascular coagulation associated with acute promyelocytic leukemia.

We measured plasma heparin cofactor II (HC II) activity in patients with disseminated intravascular coagulation (DIC) due to various underlying diseases together with the levels of antithrombin III (AT III), pseudocholinesterase (a marker of hepatic synthesis), and various haemostatic molecular markers. Both HC II and AT III were decreased in DIC secondary to all the underlying diseases studied, except acute promyelocytic leukemia (APL), when compared with healthy subjects. The lowest HC II and AT III levels was observed in coagulopathy secondary to liver disease, the HC II level in sepsis was the second lowest. In DIC due to APL, the decrease in HC II was not accompanied by a decrease in AT III. Thus, we divided all 124 samples tested into APL and non-APL groups. The HC II level correlated positively with fibrinogen and plasminogen in both the APL and non-APL groups. In the APL group, the HC II level had a significant negative correlation with the thrombin-AT III complex (TAT), fibrinogen/fibrin degradation products, and D-dimer levels as well as the prothrombin time, while AT III showed no correlations with any of the haemostatic parameters. These results suggest that HC II may be consumed preferentially by thrombin in APL patients with DIC, and thus may spare the consumption of AT III. Accordingly, HC II seems to be a superior indicator of DIC than AT III in APL patients. Moreover, replacement therapy with HC II instead of AT III may be useful to treat DIC associated with APL. In the non-APL group, the HC II levels were positively correlated with the levels of AT III and pseudocholinesterase activity. This indicates that plasma HC II levels are closely related not only to consumption coagulopathy but also to hepatic synthetic activity, as is the case for plasma AT III.

Adult↗
PubMed1992

Infrequent mutation of the ras genes in skin tumors of xeroderma pigmentosum patients in Japan.

By using PCR amplification and oligonucleotide mismatch hybridization, base-substitution mutations of the ras genes in 26 skin tumors of Japanese xeroderma pigmentosum (XP) patients were studied. Thin sections of tumor tissues which were fixed and embedded in paraffin blocks were used in this study. After analyzing codons 12, 13 and 61 of the H-, K- and N-ras genes by using 66 oligomer probes, we detected only one mutation of the K-ras gene at codon 61 in one tumor sample. All the other tumors were therefore considered not to have a mutation in the ras genes. These results suggest that mutations of the ras genes are not particularly associated with skin tumors of Japanese XP patients.

Base Sequence↗
PubMed1992

Role of the upstream region containing an intrinsic DNA curvature in the negative regulation of the phospholipase C gene of Clostridium perfringens.

The phospholipase C (alpha-toxin) gene (plc) of Clostridium perfringens was cloned into pUC19 and the effects of the upstream regions on expression of the plc gene were examined in Escherichia coli JM109. When the 0.7-kb region just upstream of the putative -35 site of the gene was deleted, production of phospholipase C increased approximately 10-fold. Northern blot hybridization analysis of the plc transcript showed that the upstream region inhibited transcription from the plc promoter. Nucleotide sequencing of this upstream region revealed that there are three periodically repeated (dA)5-6 tracts between positions -66 and -40 of the plc gene. A fragment containing this sequence showed anomalously slow electrophoretic mobility at low temperature, indicating that the region immediately upstream of the plc promoter is a locus of sequence directed DNA-bending. Nested deletions of the upstream region were created from its 5' end by exonuclease III and the effects of deletions on the expression of the plc gene were examined. When the 77-bp fragment containing the two (dA)5-6 tracts were deleted, phospholipase C production increased markedly. These results indicate that the intrinsic DNA curvature upstream of the plc promoter is involved in the negative regulation of the plc gene transcription.

Bacterial Toxins↗