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M Ohta

Publications and source records attributed to M Ohta.

At least 523 records · Page 29Linked to original sources
PubMed1995

[Eighteen cases of tortuosity of the internal carotid--usefulness of MR-angiography in diagnosis].

There have been few reports on tortuosity of the internal carotid exhibiting pulsation or swelling in the pharyngeal wall. Because this disease carries the risk of causing massive hemorrhage at the time of incision of a peritonsillar abscess, surgical treatment of the adenoids, or tonsillectomy, otolaryngologists should be aware of the existence of this disorder as a risk factor. We encountered tortuosity of the internal carotid in the pharynx in 18 cases over an approximately two year period. Females (15 cases) outnumbered males (3 cases), and the mean age was 68 years at the time of diagnosis. There was no right-to-left difference in terms of the incidence of the disease. The complication of hypertension was noted in 10 cases. MR-Angiography (MRA) was performed in 13 cases, and very clear images were obtained; this technique was useful for diagnosing this disorder. For the most part, contrast angiography has been employed for the diagnosis of this disorder, but various complications, including deaths, have been reported. As the incidence of tortuosity of the internal carotid is high in the elderly, it is thought that any complication which may occur has the potential to become serious. Non-invasive diagnostic techniques are thus recommended. MRA is absolutely non-invasive, and we therefore believe that this technique should be the modality of first choice for diagnosing tortuosity of the internal carotid.

Aged↗
PubMed1995

Time-lapse microcinematography of osteocytes.

We succeeded in the isolation of osteocytes from parietal bones of 16-day-old chick embryos. Isolated osteocytes showed a typical stellate morphology. More than 95% of these cells reacted with the osteocyte-specific antibody OB 7.3. In culture osteocytes formed gap junctions with each other, as could be established by ACAS. Sixteen-millimeter time-lapse microcinematography of the cells also demonstrated the formation of intercellular connections and gap junctions, and portrayed the interaction between osteocytes and osteoclasts: osteocytes seemed to inhibit osteoclast activity. This cinematography also showed the ability of osteocytes to proliferate after they had been disconnected from each other. Thereafter these cells redifferentiated into osteoblasts that became embedded in bone matrix produced by themselves. These findings suggest that osteocytes might be involved in bone formation during remodeling.

Animals↗
PubMed1995

Effects of parathyroidectomy on left ventricular mass in patients with hyperparathyroidism.

The effects of parathyroidectomy on left ventricular muscle volume and mechanical performance were evaluated echocardiographically in 24 patients with secondary hyperparathyroidism due to chronic renal failure and in 7 with primary hyperparathyroidism. Intraventricular septum and posterior wall thickness, left ventricular end-diastolic diameters, shortening fraction, ejection fraction, and left ventricular mass index were measured by M mode recording by the parasternal short axis view prior to parathyroidectomy as baseline and repeated 12 months after parathyroidectomy. Serum basal carboxyterminal parathyroid hormone levels in patients with secondary hyperparathyroidism (34.4 +/- 13.7 ng/ml) were significantly higher than in those with primary hyperparathyroidism (3.4 +/- 5.1 ng/ml; p < 0.0001). At 12 months after parathyroidectomy, intraventricular septum and posterior wall thickness, left ventricular end-diastolic diameter and left ventricular mass index were reduced from 11.8 +/- 3.1 mm, 10.9 +/- 1.7 mm, 53.8 +/- 6.3 mm, 200.8 +/- 57.1 g/m2 to 10.0 +/- 2.1 mm (p < 0.05), 9.8 +/- 1.9 mm (p < 0.05), 50.7 +/- 7.2 mm (p < 0.05), 149.6 +/- 38.7 g/m2 (p < 0.0001), in patients with secondary hyperparathyroidism. In patients with primary hyperparathyroidism, all echocardiographic parameters remained in the normal range and did not show any significant changes before or after parathyroidectomy. From this study, parathyroid hormone at extremely high concentrations as seen in secondary hyperparathyroidism appears to be a cardiotoxic substance. Therefore, all patients with secondary hyperthyroidism should be examined by echocardiography and parathyroidectomy should be considered if myocardial hypertrophy is present.

Adult↗
PubMed1995

Prognostic significance of hepatic vein waveform by Doppler ultrasonography in cirrhotic patients with portal hypertension.

OBJECTIVE: We prospectively evaluated the prognostic value of the flat hepatic vein waveform, measured by Doppler ultrasound, in cirrhotic patients with portal hypertension. METHODS: The Doppler pattern of right and left hepatic veins in a series of 120 consecutive cirrhotic patients with portal hypertension but without hepatocellular carcinoma was examined, together with clinical and biochemical parameters. RESULTS: Flat waveform of the right hepatic vein was recognized in nine patients and that of the left hepatic vein was seen in 13. After a mean follow-up of 13.6 +/- 9.7 months, 17 patients died, all from liver failure. In the univariate analysis, variable significantly associated with the duration of survival were age, etiology of the liver cirrhosis, upper gastrointestinal bleeding after start of the study, Child-Pugh score, ascites, encephalopathy, prothrombin index, bilirubin, albumin, and flat Doppler waveform in the right and left hepatic veins. Multivariate analysis showed that flat Doppler waveform in the right hepatic vein, bilirubin, and prothrombin index were independently related to survival. CONCLUSIONS: The prognostic accuracy in cases of cirrhosis with portal hypertension is significantly improved with acquisition of information obtained from hepatic vein waveform by Doppler ultrasound.

Adult↗
PubMed1995

Recurrent rectal bleeding from portal hypertensive colopathy in a patient with hemorrhoids.

In a 62-yr-old woman who complained of recurrent rectal bleeding, hemorrhoids with mucosal prolapse were found. Virus-related cirrhosis also was present. Colonoscopy revealed spontaneous bleeding from two rectal ectasias (portal hypertensive colopathy) located 9 cm from the anus. Endoscopic hemostasis was achieved with a heater probe, and there has been no recurrent hemorrhage. Colonoscopy is important in ruling out hemorrhage from portal hypertensive colopathy when rectal bleeding occurs in the presence of portal hypertension.

Angiodysplasia↗
PubMed1995

Tissue expression of rat ciliary neurotrophic factor (CNTF) mRNA and production of the recombinant CNTF.

We used the polymerase chain reaction to show that CNTF mRNA is widely expressed in the brain, heart, lung, liver, kidney and testis of the rat, in addition to preferential expression in the sciatic nerve. We produced the recombinant CNTF in E. coli using rat sciatic nerve cDNA and obtained high yields of pure CNTF. The biological activity of the recombinant protein was comparable to that of native rat CNTF in its support of the survival of cultured embryonic day-8 chick ciliary ganglions. Western Blot analysis using antibody against the recombinant CNTF clearly showed the presence of CNTF protein (25kD) in rabbit sciatic nerve.

Animals↗
PubMed1995

[Computed tomography findings in convergent strabismus fixus].

X-ray computed tomography (CT) of the eyeball and orbit revealed the cause of eye movement disorder in convergent strabismus fixus. The findings suggest that the disease can be diagnosed and treated at an early stage. Twelve cases of progressive esotropia with high myopia and 20 cases with normal visual acuity served as subjects in this study. The CT slice was parallel to the German horizontal plane, and the lens and medial and lateral rectus muscles were scanned. The average axial length of the affected eyes was significantly longer than in normal eyes. In progressive esotropia, the characteristic CT findings are an elongated eyeball, mechanical contact between the eyeball and lateral wall of the orbit, and a downward displacement of the lateral rectus muscle. Thus, it is reasonable to conclude that eye movement disorder in convergent strabismus fixus results from weakness of the lateral rectus muscle which has been displaced downward due to compression of the eyeball against the orbital wall.

Aged↗
PubMed1995

Feasibility of laparoscopic cholecystectomy for patients with a nonvisualized gallbladder on drip infusion cholangiography.

We report here the operative findings, the incidence of successful laparoscopic treatment, and the perioperative complications in patients with nonvisualized gallbladder on drip infusion cholangiography (DIC). Eighty-five patients with a nonvisualized gallbladder on DIC were entered into the study. None of the patients had a minimal adhesive gallbladder; 51 to 85 patients (60.0%) had moderate adhesive gallbladders, and 34 (40.0%) had severely adhesive ones. The rate of successful laparoscopic treatment, including laparoscopy-assisted abdominal surgery, was 97.6% (83 of 85 patients). Perioperative complications occurred in only three patients (3.5%), and there were no deaths related to the operation. Thus, when patients with a nonvisualized gallbladder on DIC undergo laparoscopic cholecystectomy, meticulous procedures must be carried out; however, as the rate of successful laparoscopic treatment is high, cholecystectomy under laparoscopy is feasible for experienced surgeons.

Cholangiography↗
PubMed1995

Portal venous blood flow unaltered in cirrhotic patients given metoclopramide injections.

The effects of metoclopramide on blood flow in portal and left gastric veins and cardiovascular haemodynamic variables were studied in 30 patients with both liver cirrhosis and oesophageal varices. Measurements were made under baseline conditions and after the intravenous administration of saline, metoclopramide 10 mg, and metoclopramide 20 mg. Portal haemodynamics, including portal and left gastric veins were studied using pulsed Doppler ultrasound. In all groups, the blood flow and the maximal diameter of portal and left gastric veins, and heart rate remained unchanged. However, metoclopramide 10 mg significantly decreased the mean arterial pressure 15 minutes after administration while metoclopramide 20 mg decreased it 30, 45 and 60 minutes after administration. Therefore, metoclopramide apparently does not alter the blood flow of the portal venous system in these patients.

Adult↗
PubMed1995

Effect of the proteoglycan (PSK) on lymphocyte subsets in normal rats.

The effect of the proteoglycan biologic response modifier, PSK, on lymphocyte subsets was investigated in normal rats. Six-week-old male SPF Wistar-Imamichi rats were fed a diet containing 2% PSK. Peripheral blood lymphocytes (PBL), thoracic duct lymphocytes (TDL), and those existing in the thymus, spleen and Peyer's patches were collected for analysis of subsets of T cells, helper/inducer T (Th) cells, suppressor/cytotoxic T (Ts) cells and B cells compared with those of the control group. In the PBL, differential and absolute counts of T and Th cells were lower in the group fed PSK (the PSK group) than the control group. There was no difference in Ts cells between the groups, and the PSK group showed a higher B-cell differential count. In the case of TDL, the PSK group showed greater absolute counts of T and Th cells than the control group. In tissue lymphocytes, differential T and Th cell counts were significantly greater in the PSK group than the control group, as observed first in Peyer's patches and later in the spleen. No differences between the groups were observed in these counts in the thymus. Changes in body distribution of T and Th cells induced by PSK treatment first appeared in lymphocytes in Peyer's patches, followed by PBL and TDL, and those in the spleen. No such changes were observed in the thymic lymphocytes.

Animals↗
PubMed1994

MIB1 staining index and scoring of histologic features in meningioma. Indicators for the prediction of biologic potential and postoperative management.

BACKGROUND: The biology of brain tumors, including cell kinetics, has been studied. Recently, monoclonal antibody to Ki67 (MIB1), a nuclear protein related to cell proliferation, has been analyzed immunohistochemically using tissue prepared from paraffin embedded sections. METHODS: The authors assessed the prognostic usefulness of various histologic indicators of the biologic potential of meningiomas in patients who underwent total resection (Simpson's Grade I and II) by evaluating the time to recurrence as an end point. Forty-three patients with a total of 36 meningiomas and 7 hemangiopericytomas were investigated by immunohistochemical analysis using MIB1. RESULTS: MIB1 staining index (SI) and histologic score were well correlated with the recurrence-free interval (r = -0.6749, P = 0.002 and r = -0.4939, P = 0.027, respectively) and with each other (r = 0.7909, P < 0.001). The MIB1 SI and histologic score in the nonrecurrence group were significantly lower than those in the recurrence/metastasis group (P < 0.001 and P = 0.001, respectively). The values of these indicators showed that as the value increased, so did the recurrence rate. CONCLUSIONS: Evaluation using the MIB1 SI and total histologic score of meningioma is useful in assessing the prognosis as well as postoperative management of these patients.

Adolescent↗
PubMed1994

The role of GABA in the central regulation of AVP and ANP release and blood pressure due to angiotensin and carbachol, and central GABA release due to blood pressure changes.

To assess whether GABA given intracerebroventricularly (i.c.v.) affects vasopressin (AVP) and atrial natriuretic peptide (ANP) release and changes in blood pressure in response to i.c.v. angiotensin (AT II) and carbachol (CB), or whether changes in blood pressure affect GABA release in the brain, experiments were carried out. In experiment I (Ex I), GABA (100 micrograms) with AT II (50 ng) or CB (25 ng) was i.c.v. administered in conscious rats (n = 12). The same dose of AT II or CB alone also was administered without GABA (n = 12). In experiment II (Ex II), AT II (100 ng/kg per min) or nitropuruside (NP, 10 micrograms/kg per min) was intravenously (i.v.) infused and GABA release in the area adjacent to the paraventricular nucleus was determined, using the microdialysis method, in conscious rats (n = 12). In the experiments, mean arterial blood pressure (MABP), heart rate (HR), plasma AVP and/or ANP and plasma Na+ and K+ levels were measured. In Ex I, i.c.v. AT II increased plasma AVP and MABP without changes in HR and plasma ANP, but i.c.v. GABA never affected these responses. Icv CB also increased plasma AVP and MABP with decreased HR, but did not affect plasma ANP. Icv GABA abolished bradycardiac responses, but did not affect the others. In Ex II, the pressor response to i.v. AT II increased GABA release without apparent decreases in plasma AVP. However, the depressor response to NP produced decreases in GABA release with increased plasma AVP. These results shows that i.c.v. GABA did not affect AVP and pressor responses to i.c.v. AT II and CB, but changes in blood pressure modulates GABA release in the brain with changes in plasma AVP.

Angiotensin II↗
PubMed1994

Lack of satiety effect of cholecystokinin (CCK) in a new rat model not expressing the CCK-A receptor gene.

This work expands recent observations that Otsuka Long-Evans Tokushima Fatty (OLETF) rats show little or no pancreatic expression of the cholecystokinin (CCK)-A receptor gene. We examined whether the CCK-A and -B receptor genes were expressed in the brain (hypothalamus) of OLETF rats in comparison with control (Long-Evans Tokushima Otsuka = LETO) rats. CCK-A receptor mRNA was detected in the hypothalamus of LETO rats but not OLETF rats. The CCK-B receptor gene was expressed in the hypothalamus in both strains. Cerebroventricular administration of CCK-8 sulfate inhibited daily food intake in LETO rats, but not in OLETF rats. These results show that in OLETF rats the absence of CCK-A receptor gene expression in the hypothalamus results in hyperphagia because of lack of satiety.

Animals↗