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Biomedical subjects

S Ohashi

Publications and source records attributed to S Ohashi.

At least 181 records · Page 10Linked to original sources
PubMed1986

Phosphorylation of AMP by inorganic phosphorylating agents.

AMP was phosphorylated by inorganic phosphorylating agents: cyclo-triphosphate and diphosphonate, in aqueous solution (70-80 degrees C, pH 6-12). The molecular structures of phosphorylated products were established by use of phosphorus-31 NMR and high-performance liquid chromatography (HPLC). The OH groups on AMP were phosphorylated by both phosphorylating agents to form 2'- or 3'-phosphate but an OH group on dAMP was not phosphorylated. Phosphorylation of OH group proceeds in two steps: formation of hydrogen bond between OH group and phosphorylating agent; subsequent nucleophilic attack of OH group on a phosphorus atom. Phosphate group on AMP was phosphorylated by diphosphonate but not by cyclo-triphosphate. The difference in the reactivities is explained in terms of charge repulsion between AMP and agents.

Adenosine Monophosphate↗
PubMed1985

Consistency of human liver.

Liver consistency was measured biomechanically on the left lobe during laparotomy (n = 52) and on the resected specimen (n = 24) using a specially devised technique. Its relationship with histological findings and hepatic functions was also investigated. Instrumentation included a venipuncture needle with a closed tip and a round latex microballoon attached at a side hole. The needle was connected to a pressure transducer and infusion pump with a polyethylene tube. After the needle was introduced into the liver tissue, liver consistency was measured as delta P/delta V (cm H2O/ml) from the slope of pressure rise on a Pressure (P)-Volume (V) curve obtained at constant saline infusion. Liver consistency increased proportionally with the degree of hepatic fibrosis: 589 +/- 191 (cm H2O/ml) for nonfibrosis (n = 25), 869 +/- 139 for periportal fibrosis (n = 14), 1030 +/- 116 for incomplete cirrhosis (n = 15), and 1250 +/- 206 for fully developed cirrhosis (n = 22). Correspondingly, liver consistency correlated closely with morphometrically estimated hepatic fiber content (r = 0.82, P less than 0.01). With the exception of albumin, liver function tests including prothrombin time, gamma-globulin fraction, zinc turbidity, and indocyanine green retention rate showed significant correlations with liver consistency (0.41 less than magnitude of r less than 0.68, P less than 0.001). However, correlation was much less than that between liver consistency and hepatic fiber content. The present study demonstrates that liver consistency measured by this technique can be a predictive index of hepatic fiber gradings.

Adult↗
PubMed1985

Growth hormone, thyrotropin and prolactin responses to simultaneous administration of human growth hormone-releasing factor and thyrotropin releasing hormone in the bovine.

The effects of intravenous injection of synthetic human pancreatic growth hormone-releasing factor-44-NH2 (hpGRF-44) and synthetic thyrotropin releasing hormone (TRH), or hpGRF-44 in combination with TRH on growth hormone (GH), thyrotropin (TSH), and prolactin (PRL) release in dairy female calves (6- and 12-month-old) were studied. When 0.25 microgram of hpGRF-44 per kg of body weight (bw) was injected in combination with TRH (1.0 microgram per kg of bw), the mean plasma GH concentration of the 12-month-old calves rose to a maximum level of 191.5 ng/ml (P less than 0.001) at 15 min from the value of 6.8 ng/ml before injection at 0 min. The maximum level was 3.1 and 6.1 times as high as the peak values obtained after injection of hpGRF-44 (0.25 microgram per kg of bw) and TRH (1.0 microgram per kg of bw), respectively (P less than 0.001). The area under the GH response curve for the 12-month-old calves for 3 hr after injection of hpGRF-44 in combination with TRH was 2.5 times as large as the sum of the areas obtained by hpGRF-44 and TRH injections. In contrast, the mean plasma GH level was unchanged in saline injected calves. The magnitudes of the first and the second plasma GH responses in the 6-month-old calves to two consecutive injections of hpGRF-44 in combination with TRH at a 3-hr interval were very similar. The peak values of plasma GH in the calves after hpGRF-44 injection were 2-4 times as high as those after TRH injection.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1985

The distribution of corticotrophin-releasing factor immunoreactivity in various ovine tissues.

The presence of CRF in various ovine tissues has been quantified by a radioimmunoassay using an antibody raised against ovine CRF synthesized in vitro. Acetic acid extracts of ovine hypothalamus, cerebral cortex, cerebellum, pituitary and a number of visceral organs assayed in serial dilutions gave inhibition curves parallel to those of synthetic CRF. The highest concentration of CRF immunoreactivity (CRF-I) was found in the pituitary (84.6 +/- 8.77 ng/g wet weight) and the second highest in the hypothalamus (79.1 +/- 2.77 ng/g wet weight). CRF-I in the cerebral cortex and visceral organs (stomach, duodenum, jejunum, ileum, pancreas and liver) was about 60 and 30% of that in the hypothalamus, respectively. Chromatography of extracted CRF-I from these tissues on Bio-Gel P-10, equilibrated and eluted with 0.1 M acetic acid, revealed a single immunoreactive peak corresponding to synthetic ovine CRF. These findings indicate that CRF is generally distributed throughout ovine tissues including visceral organs, although its function remains to be clarified.

Adrenal Glands↗
PubMed1985

Thermographic evaluation of the hemodynamic effect of the antithrombotic drug cilostazol in peripheral arterial occlusion.

Cilostazol (6-[4-(1-cyclohexyl-1H-tetrazol-5-yl) butoxy]-3,4-dihydro-2(1H)-quinolinone, OPC-13013) was evaluated experimentally to be effective in increasing blood flow in arterial occlusive disease. The hemodynamic effect of the drug on peripheral arterial occlusion was examined using a non-invasive thermographic technique over a certain period of time. The study included 10 patients with peripheral arterial occlusion, 7 with thromboangiitis obliterans and 3 with arteriosclerosis obliterans. Cilostazol was administered at 200 mg/day for 6 successive weeks to 7 patients (10 lower limbs and 1 upper limb) and at 100 mg/day for 6 weeks to 2 patients (3 lower limbs) and 4 weeks to 1 (1 lower limb), and the skin temperature and skin blood flow were measured in the limbs of these patients. The 200-mg/day dose brought about elevation of the two parameters at 4 and 6 weeks. The increase in skin temperature in the leg and foot at 6 weeks was statistically significant (p less than 0.05, t-test), and the increase in skin blood flow was also significant in the leg (p less than 0.05) and foot (p less than 0.1). Such increase was obtained at the lower dose of 100 mg/day, but the number of cases was too small to statistically analyze patient response.

Aged↗
PubMed1985

[Pathophysiology of defecatory disturbance in the patient with Hirschsprung's disease and chronically constipated patients with simple megarectum].

The disturbance of defecation in the patient with Hirschsprung's disease and the pathophysiology of constipation in the constipated patient with simple megarectum were investigated. In Hirschsprung's disease, an existence of aganglionosis and the sphincter achalasia are two main factors which cause clinical symptoms such as chronic constipation and megacolon. As a surgical treatment, we have routinely performed our modified Duhamel's operation. Postoperative followup study indicated that the most cases in our series have gained a satisfactory defecatory function 1 to 3 years after operation. In chronically constipated patient with simple megarectum, on the other hand, it was found manometrically that the most of them had significantly high anal canal pressure and incomplete anal relaxation after rectal stimulation. These findings indicate that those patients have hypertonic and achalasic sphincter. Therefore, the authors propose "high anal pressure syndrome (HAPS)" for such constipated patient with simple megarectum. As to the surgical treatment, 6 patients with simple megarectum had a complete posterior internal sphincterotomy and the postoperative results were excellent or good in our series.

Adolescent↗
PubMed1984

Changes in protein phosphorylation in guinea pig polymorphonuclear leukocytes by treatment with membrane-perturbing agents which stimulate superoxide anion production.

Phosphorylation of proteins was examined in guinea pig polymorphonuclear leukocytes in relation to the effects of membrane-perturbing agents, which stimulate superoxide anion production, and their inhibitors. The phosphorylation was detected by 32P autoradiography after separation by two-dimensional electrophoresis of proteins phosphorylated in 32P-preloaded cells. Though phosphorylation of various proteins was stimulated by each of the membrane-perturbing agents, the stimulation was especially marked in six proteins. Phorbol myristate acetate and digitonin enhanced the phosphorylation of the six proteins, while myristate and concanavalin A increased the phosphorylation of five and three proteins, respectively, out of the six proteins. p-Bromophenacyl bromide, an inhibitor of phospholipase A2, inhibited the stimulatory effect of phorbol myristate acetate on both superoxide anion production and protein phosphorylation. Trifluoperazine, a calmodulin inhibitor, also inhibited the effect of phorbol myristate acetate on both, except for an increase in the phosphorylation of one out of the six proteins. alpha-Methylmannoside, an inhibitor of concanavalin A binding, inhibited the stimulation of the phosphorylation of the three proteins by concanavalin A. The results indicate that the activation of superoxide anion production by the membrane-perturbing agents in guinea pig polymorphonuclear leukocytes is accompanied by the phosphorylation of, at least some of, these six proteins.

Animals↗
PubMed1984

An experimental study on the mechanism of rectosphincteric reflex in special reference to Hirschsprung's disease.

In order to clarify the mechanism of rectosphincteric reflex (RSR), an experimental study was performed using mongrel canine models. The RSR exists in normal anesthetized mongrel dogs. It does not disappear in dogs with isolation of the rectoanal portion from the surrounding tissues. The RSR disappeared after circular transection of the rectal muscle coat at the level between the rectum and the anal canal, and also after selective destruction of the myenteric plexus of the rectum. These data suggest that the RSR is a local reflex contained within the rectoanal wall and its regulating center and neural pathway are in the myenteric plexus of the rectum.

Anal Canal↗
PubMed1984

Growth hormone response to human pancreatic growth hormone releasing factor in cattle.

The effects of a growth hormone releasing factor, human pancreatic growth hormone releasing factor-44 (hpGRF-44), on growth hormone (GH) secretion in calves, heifers and cows were studied. A single intravenous (iv) injection of 0.1, 0.25, 0.5 or 1.0 microgram of synthetic hpGRF-44 per kg of body weight (bw) in calves significantly elevated the circulating GH level within 2-5 min, while no increase in plasma GH was observed in saline injected control calves. The plasma GH level increased proportionally to the log dose of hpGRF-44, and reached a peak at 5-10 min (p less than 0.01). Subcutaneous injection of hpGRF-44 also elevated the plasma GH level, but the peak value at 15 min was 37% of that of iv injection (p less than 0.05). Intravenous injection of 0.25 microgram of hpGRF-44 per kg of bw to female calves, heifers, and cows significantly elevated mean the GH levels from 8.5, 2.3, and 1.6 ng/ml at 0 time to peak values of 97, 26, and 11.6 ng/ml, respectively (p less than 0.01). The plasma GH response and basal level in calves were significantly higher than those of heifers or cows (p less than 0.025). The plasma GH response to hpGRF-44 as well as the basal level decreased with advancing age. The plasma GH response to hpGRF-44 and basal GH in male calves were significantly greater than those in female calves (p less than 0.001). These results indicate that synthetic hpGRF-44 is a potent secretogogue for bovine GH, and suggest its usefulness in the assessment of GH secretion and reserve in cattle.

Animals↗
PubMed1983

Serum and erythrocyte acetylcholine esterase in Hirschsprung's disease.

Determination of acetylcholine esterase in serum (S-AChE) and erythrocytes (E-AChE) was carried out in nine patients with Hirschsprung's disease and 16 normal controls. S-AChE was significantly elevated in patients with Hirschsprung's disease, while no significant difference was observed in E-AChE in these two groups. In 17 patients with Hirschsprung's disease, S-AChE and E-AChE were determined after definitive operation. Twelve of these patients underwent a Duhamel type procedure in which a small part of the aganglionic bowel segment remained unresected. Five patients were treated by Swenson's procedure performing complete resection of the aganglionic bowel segment. S-AChE in patients treated by the Duhamel type procedure remained elevated, while it was as low as that in normal controls in patients who underwent Swenson's procedure. There was no significance in E-AChE in both groups. This study suggests a close relation of the level of S-AChE to the extent of the aganglionic bowel segment in Hirschsprung's disease.

Acetylcholinesterase↗
PubMed1981

Simple modification of Duhamel's operation for the treatment of Hirschsprung's disease. 11 year results.

Surgery was performed in 45 patients with Hirschsprung's disease utilizing our modified Duhamel's procedure. A specifically designed crushing clamp was used to eliminate the development of a blind rectal pouch and the suture line of the retained rectal end. Postoperative complications were relatively rare. Manometric study indicated that most postoperative patients had anorectal function as satisfactory as that of normal control subjects. These results suggest that our modified procedure has great advantages in terms of safety and satisfactory defecatory function for the treatment of Hirschsprung's disease.

Child↗
PubMed1981

Exercise stress body surface isopotential map in patients with coronary artery disease: comparison with coronary angiographic and stress myocardial perfusion scintigraphic findings.

to locate the ischemic area in 22 patients with angina pectoris, exercise stress body surface isopotential maps (MAPs) were assessed and compared with coronary angiography and myocardial stress scintigraphy. Taking coronary angiographic findings into consideration, 4 types of ischemic MAP responses, i.e., septum and anterior, lateral, inferior, and posterior wall ischemia were postulated. Sensitivity of stress MAP was 71% for the average and more than stress imaging. Specificity of stress MAP was 46% for the average and less than stress imaging.

Angina Pectoris↗