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T Ohara

Publications and source records attributed to T Ohara.

At least 145 records · Page 8Linked to original sources
PubMed1992

[Changes in size of adult renal allografts in pediatric recipients, clinicopathologic study of decreased graft size in infant recipients and hypertrophy, renal growth in older children].

It is presumed that graft size after renal transplantation from adult donor decreases in infant or very young recipient and increases in older recipient. Measurement of graft length, width, parenchymal thickness on intravenous pyelography (IVP) films, measurement of area of Bowman's capsule, glomerulus, capillary tuft and tubule on graft biopsy specimens were compared between 3 months and 1 year after renal transplantation. The graft sizes decreased in recipients below 6 years-old or body height (Ht.) 90 cm and increased in recipients above 6 years-old, Ht. 100 cm. The case of decreased graft size was found a decrease of area of Bowman's capsule, glomerulus, capillary tuft and tubule. We suggest that it is caused by a difference between renal blood flow in infant and in adult. It is suggested that graft hypertrophy depends predominantly on increased tubular size and capillary tuft enlargement occurs prior to glomerular, tubular change. But, an increase in creatinine clearance (Ccr) was not found following graft hypertrophy.

Child↗
PubMed1992

[A case report of so-called solitary fibrous tumor of the mediastinum].

A 52-year-old house wife was admitted to our hospital with the diagnosis of a impending rupture of the aneurysm of the ascending aorta. Chest X-ray showed an anterosuperior mediastinal mass which extended into right hemithorax and space between ascending aorta and superior vena cava on CT and MRI. Median sternotomy showed a large mass, arising from the left lobe of the thymus covered with mediastinal pleura and projecting into the right pleural cavity with no dissemination. The tumor was excised with the thymic glands together with the involved ascending aorta and pericardium. It was encapsulated tumor, 10 x 9 x 8 cm in size, 420 g in weight, and revealed central necrosis with bleeding on the cut surface. The pathological findings showed spindle cell tumor with high mitotic activity, immunoreactivity for vimentin, but not for keratin, and no ultrastructural evidence of micro villi. So far as the Japanese literature about the so-called solitary fibrous tumor of the mediastinum is concerned, this is considered to be the first case in our country.

Female↗
PubMed1991

The effects of age and anesthetic solubility on anesthetic-induced opisthotonus in mice.

In our previous report which indicated volatile anesthetics-induced opisthotonus in mice, we hypothesized that opisthotonus might relate with the rapidity of anesthetic induction, i.e., the blood/gas partition coefficient of the agent. To confirm this, we determined the incidence of opisthotonus induced by four different halogenated ethers (2.0% sevoflurane, 1.3% isoflurane, 2.0% enflurane, and 0.5% methoxyflurane) and 1.0% halothane, a haloalkane, in male ddN mice. The effect of age on opisthotonus was also evaluated by using young (10 +/- 2 weeks), middle-aged (6 +/- 1 mouths), and elderly (12 +/- 1 months) groups of male ddN mice. In each age group, the incidence of opisthotonus occurred in the following order: sevoflurane > isoflurane > enflurane > methoxyflurane > halothane. This partly supports our hypothesis as far as halogenated ethers are concerned. Halothane rarely produced opisthotonus. In the sevoflurane, isoflurane, and methoxyflurane groups, incidence was lower in middle-aged than in young or elderly mice, while incidence increased with age in the enflurane group.

Journal Article↗
PubMed1991

Vascular smooth muscle cells from genetically hyperlipidemic rabbit (WHHL rabbit) exhibit decreased growth response.

The Watanabe Heritable Hyperlipidemic (WHHL) rabbit is a widely studied animal model for the human genetic disorder familial hypercholesterolemia, and spontaneously develops atherosclerotic disease. We studied the growth characteristics of cultured vascular smooth muscle cells (VSMC) from WHHL rabbits compared with VSMC from Japanese white rabbits. We measured cell proliferation, DNA synthesis, and c-myc proto-oncogene expression, in response to growth stimuli such as fetal bovine serum (FBS) and platelet-derived growth factor (PDGF). VSMC from Japanese white rabbits exhibited a 4-fold increase in cell numbers during a 5-day incubation period compared with those from WHHL rabbits. FBS and PDGF stimulated DNA synthesis, as measured by thymidine incorporation into VSMC, in both Japanese white rabbits and WHHL rabbits, however the response was significantly higher in the former strain. The intracellular pH value of VSMC determined using the pH-sensitive fluorescence dye 2',7'-bis-carboxyethyl-carboxyfluorescein was significantly higher in WHHL rabbits than in Japanese white rabbits. Proto-oncogene c-myc was induced by exposure of VSMC to FBS, however there was no significant difference in c-myc mRNA levels between the two strains. These results suggest that VSMC from WHHL rabbits are not genetically growth accelerated, but show decreased growth response to growth stimuli.

Animals↗
PubMed1991

Isozyme polymorphisms in human diploid cell strains for research on cellular aging.

Six human lung diploid cell strains established for the study of in vitro cellular aging (TIG-1, TIG-7, WI-38, IMR-90, MRC-5, MRC-9, and HeLa cells as a control) were studied by cellulose acetate membrane electrophoresis for allozymic differences at 18 enzyme loci. Eight enzyme loci (G6PD, PGM1, PGM3, PepA, PGD, ADA, GLO1, and ME), proved to be informative in establishing unique allozyme genetic signatures for all of the cell strains established from the same species and from the same organ. Changes in the allozyme genetic signatures were not observed throughout the life span of TIG-1 and MRC-9 cells. The allozyme genetic signatures can be used as a quick monitor of cell identification and intraspecific cell contamination.

Cell Line↗
PubMed1991

Renal pelvic carcinoma which shows metastatic potential to distant organs, induced by N-butyl-N-(4-hydroxybutyl)nitrosamine in NON/Shi mice.

Renal pelvic carcinoma was induced in mice by giving N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN). Initially, differences in renal pelvic carcinogenesis by BBN were examined in three male mouse strains: NON/Shi, which demonstrate spontaneous hydronephrosis with incidences of 10-30%, and DS/Shi and B6C3F1, which do not exhibit hydronephrosis. When mice of these strains were given 0.05% BBN in the drinking water for 12 weeks followed by water without BBN for 8 weeks, renal pelvic carcinoma morphologically similar to human carcinomas developed in 8 of 23 NON/Shi mice (35%). Metastasis to the lung was found in one of them (13%). B6C3F1 and DS/Shi mice had no pelvic tumors, but the response to urinary bladder carcinogenesis in NON/Shi mice was nearly equal to that in DS/Shi and B6C3F1 mice. These results suggest that renal pelvic carcinogenesis is related to the presence of stagnant urine containing carcinogen in the renal pelvis. In a second experiment, we examined renal pelvic carcinogenesis in NON/Shi mice given BBN for 4 weeks followed by water without BBN for 32 weeks. The incidence of renal pelvic carcinoma (28%) was similar to that in the first experiment, but the incidence of metastasis was markedly elevated to 60%. These results indicate that BBN treatment can induce renal pelvic carcinoma which often metastasizes to the lung in NON/Shi mice.

Abdominal Neoplasms↗
PubMed1991

Renal involvement in POEMS syndrome.

We describe a patient with POEMS syndrome whose renal biopsy specimen also showed nephropathy. Immunoelectron microscopy of the renal biopsy revealed the localization of immunoglobulin (IgA and lambda light chain) in the subendothelial space of the glomerular capillaries, a previously unrecognized finding. We conclude that the renal pathology in POEMS syndrome is unusual and distinct from microangiopathic glomerular involvement or idiopathic mesangiocapillary glomerulonephritis.

Adult↗
PubMed1991

Subanesthetic concentrations of volatile anesthetics may enhance acquired avoidance training in ddN mice.

The effects of halothane, enflurane, and isoflurane on avoidance training were assessed in male ddN mice. Animals were trained to escape an aversive unconditioned stimulus (electric foot shock) within 3 s after being exposed to a conditioned stimulus (light and buzzer). Immediately after training (first session), the animals were exposed to halothane, enflurane, or isoflurane for 120 min and were then tested again on the avoidance task (second session) 30 min after cessation of the exposure. The performance ratios [B/A] (i.e., A is the score in the first session, and B the score in the second) were compared between the anesthetic groups and their respective control groups. Performance ratios in the control animals ([B/A]c) did not reach 100% except for those corresponding to the 0.5 and 1.0 MAC (minimal alveolar anesthetic concentration) halothane groups. Four of the nine performance ratios in the anesthetic groups ([B/A]a) exceeded 1.0. [B/A]a exceeded [B/A]c by 18.7% in the 0.25 MAC halothane group (P less than 0.05), by 13.5% in the 0.31 MAC enflurane group (i.e., not significant), and by 17.3% in the 0.29 MAC isoflurane group (P less than 0.01). [B/A]a/[B/A]c decreased dose-dependently for each anesthetic group. These results suggest that low concentrations of halothane, enflurane, and isoflurane may enhance the performance of ddN mice in acquired avoidance training performed 30 min after anesthetic exposure.

Anesthesia, Inhalation↗
PubMed1991

Histological study of pulmonary vasculature in fatal cases of persistent pulmonary hypertension of the newborn.

Using our own morphometric technique, we examined pulmonary vasculature in eight neonates who died of persistent pulmonary hypertension of the newborn (PPHN). PPHN was judged to be idiopathic in three neonates and was associated with fatal meconium aspiration in the other five. Two characteristic structural features of PPHN were revealed in this study. First, medial thickening of the normally fully-muscularized pulmonary vessels occurred in the smaller and more peripherally located arteries. Second, fully-muscularized vessels extended as far as the intraacinar arteries, which are normally non-muscular vessels at this age. This structural abnormality appears not to merely represent a failure of the fetal pattern to regress, and it is suggested that PPHN is due to a structural abnormality of the pulmonary microcirculation in fatal cases.

Humans↗
PubMed1991

Effects of indomethacin in utero on the pulmonary vasculature of the newborn lambs.

Exposure of the fetus to indomethacin and the resultant closure of the ductus arteriosus in utero has been suggested to be one possible cause of persistent pulmonary hypertension of the newborn (PPHN). We examined whether or not closing the ductus arteriosus of fetal lambs by the administration of in-domethacin to the fetus and ewe could produce the functional and structural changes of PPHN. Three treated and four non-treated lambs were delivered by cesarean section. Postnatal hemodynamics were studied in two of the treated lambs. Pulmonary arterial pressure gradually decreased after delivery and did not reveal features compatible with PPHN, while the blood gases remained within the physiological range. However, acute hypoxemia produced a re-elevation in pulmonary arterial pressure. Morphometric analysis showed the medial thickening of normally fully-muscularized pulmonary arteries, but there was no abnormal extension of fully-muscularized arteries to the intraacinar level in the treated lambs. In conclusion, we could not reproduce functional and structural changes of PPHN in newborn lambs by the administration of indomethacin in utero. However, our experimental animal model with excessive muscularization of the pulmonary vasculature appears to be useful for studying vasoconstriction in response to hypoxemia.

Animals↗
PubMed1991

Effect of diabetes on cytosolic free Ca2+ and Na(+)-K(+)-ATPase in rat aorta.

We examined Na(+)-K(+)-ATPase activity and the levels of alpha I-, alpha II-, and beta-subunit mRNA and protein in aortic cells of diabetic rats. Diabetes was induced by streptozocin. Na(+)-K(+)-ATPase activity was significantly reduced on the 2nd day of diabetes (9.4 +/- 1.3 vs. 17.5 +/- 2.1 mumol NADH.mg-1 protein.h-1, P less than 0.05) and remained depressed on days 7 and 14. The levels of 5.3-kilobase (kb) mRNA band of the catalytic alpha II-subunit of Na(+)-K(+)-ATPase were also decreased on the 2nd day of diabetes, whereas the second band, 3.4 kb, was not affected. Both bands were significantly decreased on days 7 and 14. This was followed by a reduction in the levels of alpha II-protein (day 14). The levels of alpha I- and beta-subunit mRNA and alpha I- protein were not affected by diabetes. A decrease in Na(+)-K(+)-ATPase activity was accompanied by a significant (P less than 0.001) increase in the cytosolic free Ca2+ concentrations [( Ca2+]i) in diabetic aortic cells (221 +/- 18 nM on the 7th day and 242 +/- 17 nM on the 14th day vs. 153 +/- 7 nM in controls). These findings are consistent with the hypothesis that decreased Na(+)-K(+)-ATPase activity and gene expression in vascular smooth muscle cells with accompanied rises in [Ca2+]i may be an important pathogenetic factor in the development of hypertension and atherosclerosis in diabetes.

Animals↗
PubMed1991

Coronary angioscopy: a monorail angioscope with movable guide wire.

A new angioscope was devised for easier visualization of the coronary artery. In its tip, the angioscope (Olympus) with an outer diameter of 0.8 mm had a metal lumen, through which a 0.014-in steerable guide wire passed. Using a 8F guiding catheter and a guide wire, it was introduced into the distal coronary artery. With injection of warmed saline through the guiding catheter, the coronary segments were visualized. In the attempted 70 vessels (32 left anterior descending [LAD], 10 right coronary [RCA], 28 left circumflex [LCX]) from 48 patients, 60 vessels (86%) were successfully examined. Twenty-two patients who underwent attempted examination of both LAD and LCX; both coronary arteries were visualized in 19 patients (86%). In the proximal site of the lesion, 40 patients have the diagonal branch or the obtuse marginal branch. In 34 patients (85%) the angioscope was inserted beyond these branches. In 12 very tortuous vessels, eight vessels (67%) were examined. In conclusion, the new monorail coronary angioscope with movable guide wire is useful to examine the stenotic lesions of the coronary artery.

Angioplasty, Balloon, Coronary↗
PubMed1991

[Two cases of 2.8-dihydroxyadenine stone with a partial deficiency of adenine phosphoribosyltransferase].

We report two cases of 2.8-dihydroxyadenine stones due to partial deficiency of adenine phosphoribosyltransferase. The first patient is a 41-year-old female. Radiologic examination revealed left radiolucent renal stones and contracted kidney. Left nephrectomy was performed. Infrared spectrometric analysis of the stones revealed 2.8-dihydroxyadenine calculi. The adenine phosphoribosyltransferase activity in lymphocyte (T cell) was 19.5% of the control level. After the operation, the patient was given 300 mg/day of alloprinol. There have been no signs of recurrence. The second patient was a 52-year-old male. Radiologic examination revealed radiolucent stones of the right kidney and the urine bladder. Percutaneous nephrolithotomy and cystolithotripsy were performed. Infrared spectrometric analysis of the stones revealed 2.8-dihydroxyadenine calculi. The adenine phosphoribosyltransferase activity in the lymphocytes (T cell) was 21% of the control level. After the operation the patient was given 200 mg/day of alloprinol and put on a low purine diet. There have been no signs of recurrence.

Adenine↗
PubMed1991

[Reconstruction of femoral vein using ePTFE grafts].

Rare cases of reconstruction of peripheral veins were reported. We experienced two patients with liposarcomas of the thigh in which the femoral vessels were resected with the tumor and reconstructed with ePTFE grafts. In a 51-year-old male, the left femoral vein was reconstructed with an ePTFE graft 6 mm in diameter and 11 cm in length; but the graft occluded early in the postoperative period. In another case, a 33-year-old male, the right femoral vein was reconstructed with a ringed ePTFE graft 8 mm in diameter and 9 cm in length, with an arterio-venous fistula. The graft maintained its patency for 7 months after surgery.

Adult↗
PubMed1991

[A cytoprotective role of extracellular superoxide dismutase in experimental stress ulcer models].

In an experimental stress ulcer models, we examined a pathophysiological role of EC-SOD in an extracellular fluid in guinea pig. Heparin has a releasing potency of EC-SOD into extracellular fluid from endothelial cell. In this study, we divided animals into four groups; 1) control animals, 2) animals injected with heparin (1,000 IU/kg), 3) animals injected with heparin and DDC (1 g/kg), 4) animals injected with DDC treatment. In these four groups, we measured ulcer index (UI) and lipid peroxides (LPO) of the gastric mucosa, before and serially after stress. Water-immersion, ethanol and burn were used as experimental stress. Animals injected with heparin inhibited the increase of UI and LPO of gastric mucosa induced by stress. This cytoprotective effect was abolished by DDC treatment. These results suggest that EC-SOD may be a cytoprotective factor in an extracellular fluid.

Animals↗
PubMed1990

Rat liver arginase suppresses mixed lymphocyte reaction.

An inhibitory factor to mixed lymphocyte reaction (MLR) was purified from the supernatant of rat liver homogenate by procedures including chloroform treatment, ammonium sulfate precipitation, ion-exchange column chromatography, and gel filtration. The molecular weight of the purified inhibitor was 34,000 on SDS-PAGE. We determined the amino acid sequence of the N-terminal region of the purified inhibitor to be Glu-Glu-Pro-Trp-Met-Ser-Met-Ser-Ser-Lys-Pro-Lys-Pro-Ile-Glu-. This sequence shows a high homology to a rat arginase, the amino acid sequence of which was predicted from the nucleic acid sequence of cloned rat arginase cDNA. The amino acid sequence of the purified arginase is 6 amino acid residues longer than the predicted one. The purified MLR inhibitor showed a high arginase activity. The inhibition mechanism was studied and it was discovered that L-arginine was depleted in the culture medium, and that the supply of L-arginine to the cell culture caused recovery of the incorporation of tritium thymidine. Here we present evidence that the MLR inhibitor from rat liver homogenate is the liver arginase. It is noteworthy that immune response may be controlled by a liver factor.

Amino Acid Sequence↗
PubMed1990

[Clinical evaluation of Cernilton on benign prostatic hypertrophy--a multiple center double-blind study with Paraprost].

A multiple center double blind study was performed to study the effectiveness of Cernilton (CN) on benign prostatic hypertrophy in comparison to Paraprost (PP). Among a total of 192 patients, overall effect was studied on 159 patients, overall safety rate on 178 patients and rate of effectiveness on 159 patients. There were no differences between the two groups in the selected patients, criteria for exclusion and drop out cases or background data of the patients. Impression of patients and overall effect by committee and physician judgment were slightly higher in the CN group compared to the PP group, but there was no significant difference between the two groups. For the improvement in subjective symptoms, the rate of moderate improvement or more after 4 weeks by committee judgement was higher in the CN group compared to the PP group. The rate of improvement in protracted miction, which is an effective marker of urinary disturbance, was also higher in the CN group compared to the PP group. An analysis of objective symptoms showed a significant improvement in residual urinary volume, average flow rate, maximum flow rate and prostatic weight in the CN group. A significant improvement in the phased change of residual urinary volume was also seen in the CN group. No side effects or abnormalities in clinical test levels were noted in the CN group. By committee judgement, the rate of more than moderate effectiveness was 49.1% in the CN group compared to 41.2% in the PP group, but there was no significant difference between the two groups. By physician's judgment, the rate of more than moderate effectiveness was 49.4% in the CN group compared to 46.3% in the PP group, but there was also no significant difference between the two groups. These results suggested that Cernilton was an effective drug for benign prostatic hypertrophy.

Aged↗