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Biomedical subjects

K Takano

Publications and source records attributed to K Takano.

At least 343 records · Page 19Linked to original sources
PubMed1989

Effects of ingestion of glucose on GH and TSH secretion: evidence for stimulation of somatostatin release from the hypothalamus by acute hyperglycemia in normal man and its impairment in acromegalic patients.

Ingestion of glucose is known to induce suppression of GH secretion in normal subjects and this phenomenon is often absent in acromegalic patients. To clarify the mechanism of GH suppression in acute hyperglycemia in normal subjects and disturbed GH response in acromegalic patients, the effects of acute hyperglycemia on plasma GH and TSH levels were examined in normal subjects and acromegalic patients. Plasma GH levels were significantly lowered 45-60 min after ingestion of 75 g glucose and elevated at 210 and 240 min in nine normal subjects. Plasma TSH levels were also significantly lowered between 45 and 120 min after ingestion; levels then gradually rose. Subcutaneous administration of 50 micrograms SMS 201-995, a long acting somatostatin analog, lowered plasma TSH levels in both normal subjects and acromegalic patients, and there was no significant difference in the degree of decrease in plasma TSH levels between the normal subjects and patients. These results, taken together with several reports that somatostatin suppresses TSH secretion as well as GH secretion, suggest that acute hyperglycemia stimulates somatostatin release from the hypothalamus, thus causing inhibition of GH and TSH secretion. However, in ten acromegalic patients, only two showed suppression of plasma GH levels to below 50% of basal level and the degree of suppression of TSH secretion was significantly less than in normal subjects in the glucose tolerance test. It is, therefore, suggested that somatostatin release in response to acute hyperglycemia is impaired in most acromegalic patients and that this abnormality may be one of causes for the absence of the normal GH response to acute hyperglycemia in this disorder.

Acromegaly↗
PubMed1989

Blocking effects of tetanus toxin and its fragment [A-B] on the excitatory and inhibitory synapses of the spinal motoneurone of the cat.

A highly purified fragment [A-B] preparation (5.5 micrograms of protein in 5 or 10 microliters which is far less than the minimal lethal dose), free from contamination with the whole toxin, was injected intraspinally into the neighbouring area of the gastrocnemius motoneurone pool (eight cats). Tetanus toxin (27 micrograms protein, about 100 LD50) in 5 or 10 microliters (four cats) and 10 microliters of Ringer's solution (four cats) were injected in the same way. Fragment [A-B] depressed both the monosynaptic reflex (MSR) of the gastrocnemius motoneurone pool and its inhibition by conditioning stimulus on the antagonistic peroneal nerve almost simultaneously in the individual cats, in contrast to the whole toxin which blocked first the inhibition of the MSR and later the MSR itself. The effects of fragment [A-B] appeared late, at about the time when the whole toxin blocked the MSR. The cats injected with fragment [A-B] did not die by intoxication. Fragment [A-B] at high doses (up to 120 micrograms) injected intramuscularly into the rat had no effect on neuromuscular transmission. The results clearly showed a blocking action of fragment [A-B] on inhibitory and excitatory synapses of the spinal motoneurones.

Animals↗
PubMed1989

Presynaptic inhibition of the monosynaptic reflex during local tetanus in the cat.

Tetanus toxin at doses of 2-2000 mouse MLD/kg was injected into the gastrocnemius muscle of the left hind limb of the cat. Acute experiments were performed at various times thereafter, when the intoxicated hind leg was strongly extended. Presynaptic inhibition of the monosynaptic reflex (MSR) of gastrocnemius motoneurones was tested by applying conditioning single electric stimuli to the antagonistic deep peroneal nerve. In most intoxicated animals the delayed inhibition of the MSR could still be observed at time intervals typical for presynaptic inhibition. However, the amplitude of the MSR often showed a strong toxin-induced facilitation at about 30 msec after the conditioning stimulus which could mask the presynaptic inhibition and sometimes made it difficult to observe it at all. After spinal transection at the Th1 level the inhibition could be better observed in such cases. Further evidence for the resistance of the presynaptic inhibitory system against the tetanus toxin in the given dose range was given by recordings of distinct dorsal root potentials which were abolished, together with the MSR inhibition by i.v. injection of picrotoxin. It is concluded that the mechanism of presynaptic inhibition remains intact or is even lengthened during local tetanus after i.m. injection of moderate, clinically relevant, toxin doses.

Animals↗
PubMed1989

Studies on intestinal motility and mechanism of cholangitis after biliary reconstruction.

Cholangitis is a serious complication of biliary reconstruction for congenital biliary atresia. To observe the effect of intestinal motility on the mechanism of cholangitis, we studied intestinal motility in dogs after experimental common duct ligation and reconstruction by Roux-en-Y or interposition cholecystojejunostomy. One year after operation, bipolar electrodes were implanted in the canine intestine and electromyograms were performed. Distinct patterns of propagation and the direction of intestinal motility characteristic of each procedure were observed. The animals with Roux-en-Y loops showed a decrease in motility of the duodenum and upper jejunum. Those with an interposed segment demonstrated stagnation in both the duodenum and jejunum, and poor coordination of intestinal movement. The myoelectric activity of the Roux-en-Y loop suggests that it is the reconstruction technique most likely to prevent reflux cholangitis.

Anastomosis, Roux-en-Y↗
PubMed1989

Characteristics of mutant mice (ICGN) with spontaneous renal lesions: a new model for human nephrotic syndrome.

Spontaneous nephrotic mice (ICGN mice), a new mutant strain of mouse from outbred ICR, were clinically, macroscopically, histologically and immunohistochemically studied to establish their value as a model for human nephrotic syndrome. Most of the affected mice developed proteinuria, hypoproteinaemia and hypercholesterolaemia, and some of them developed systemic oedema. A high concentration of blood urea nitrogen (BUN) and a low haematocrit value were also observed. The kidneys of severe cases showed a decrease in size and had a yellowish granular surface. These findings indicated that the mice were terminally affected by chronic renal insufficiency. Histopathology demonstrated glomerular lesions consisting of thickened basement membranes of the capillary loops with irregular spike-like protrusions and enlargement of the mesangium unaccompanied by cellular proliferation. The immunofluorescence technique revealed positive granular staining for IgA, IgG and IgM and to a lesser extent for C3 along the capillary loops in affected mice. The similarity between this spontaneous disease and human nephrotic syndrome caused by idiopathic glomerular lesions is discussed. ICGN mice may be a useful animal model for this human disease.

Animals↗
PubMed1989

Biological effects of lipopolysaccharide from Achromobacter stenohalis on lymphocytes and macrophages.

The immunopotentiating activities of lipopolysaccharide from Achromobacter stenohalis (A-LPS) were examined. A-LPS was structurally atypical and gave no endotoxin shock in A-LPS-inoculated mice. Analysis in vitro showed that A-LPS was a potent activator of both macrophages and B-lymphocytes. After macrophage stimulation with A-LPS, interleukin-1 (IL-1) secretion, interferon (IFN) production and chemiluminescence (CL) response were induced. A-LPS was a potent mitogen for spleen lymphocytes. However, induction of interleukin-2 (IL-2) secretion in T lymphocytes was not observed. These activities of A-LPS were similar to or higher than that of enterobacterial LPS.

Alcaligenes↗
PubMed1989

Oral flora of mongrel and beagle dogs with periodontal disease.

The plaque flora was studied in adult mongrel and beagle dogs with periodontal disease. Gingival plaque from maxillary premolars was removed and cultured on various growth media. The flora in all dogs was composed of mostly anaerobic gram negative rods. Bacteroides asaccharolyticus was found in the highest proportion of plaque samples from mongrel dogs, and decomposed hydrogen peroxide suggesting catalase activity. Fusobacterium nucleatum was found in higher proportion in the plaque of beagle dogs as compared to B. asaccharolyticus. With the increasing numbers of obligative anaerobic gram negative organisms such as B. asaccharolyticus, the proportions of Streptococcus, Enterococcus and Staphylococcus decreased in the dogs with periodontal disease. The salivary flora was different from the plaque flora of the dogs with periodontal disease. It was constant regardless with the disease. The salivary flora of beagle dogs with the healthy gingiva was different from that of mongrel dogs. Enterococcus, Lactobacillus, Eubacterium and black-pigmented Bacteroides (BPB, mainly B. asaccharolyticus) were higher proportion in the flora of beagle dogs as compared to mongrel dogs, while Fusobacterium, Enterobacteriaceae, yeast and molds were lower in the flora. The results reveal that B. asaccharolyticus and F. nucleatum are common pathogens and uniquely contribute to the development of gingival inflammation in dog.

Animals↗
PubMed1989

Treatment of 80 patients with Turner's syndrome with recombinant human growth hormone (YM-17798) for one year: the results of a multicentric study in Japan. Committee for the Treatment of Turner's Syndrome.

A total of 80 patients with Turner's syndrome were treated with methionine-free recombinant hGH (r-hGH) for one year. Thirty-nine patients were treated with r-hGH at weekly dosage of 0.5 IU/kg and forty-one were treated with 1.0 IU/kg/w by daily sc injection. Both treatment groups showed a statistically significant growth increase during the treatment from 3.7 +/- 1.0 to 6.0 +/- 1.1 and 7.2 +/- 1.3 (mean +/- SD) cm/year, respectively. Fifty-nine percent of the patients treated with 0.5 IU/kg/w and 87.8% of the patients treated with 1.0 IU/kg/w showed a growth rate more than 2 cm greater than the pretreatment values. Plasma somatomedin C levels were elevated and no remarkable advances in bone age were observed during the treatment in both treatment groups. An antibody against to hGH was observed in 6.8% of the patients. Otherwise, there were no significant changes in physical or laboratory examinations. No glucose intolerance was observed. These results indicate that hGH treatment is useful in accelerating growth velocity in patients with Turner's syndrome.

Adolescent↗
PubMed1989

Treatment of 94 patients with Turner's syndrome with recombinant human growth hormone (SM-9500) for two years--the results of a multicentric study in Japan. Committee for the Treatment of Turner's Syndrome.

A total of 94 patients with Turner's syndrome were treated with methionine-free recombinant hGH for one to two years. Forty-seven patients were treated with r-hGH at a weekly dosage of 0.5 IU/kg and another 47 were treated with 1.0 IU/kg/w by daily sc injection. Both treatment groups showed statistically significant growth increase during the treatment from 3.7 +/- 1.0 to 5.2 +/- 1.3 and from 3.5 +/- 0.9 to 6.3 +/- 1.4 (Mean +/- SD) cm/year, respectively, during the first year of treatment. During the 2nd year of treatment, the growth rate declined to 4.1 +/- 1.1 cm/year under 0.5 IU/kg/w treatment and to 4.6 +/- 1.1 cm/year under 1.0 IU/kg/w treatment. Nevertheless, the growth rates in the treatment groups remained significantly greater than in the untreated controls. Plasma somatomedin C increased and no remarkable increase in bone age was observed during the treatment in either treatment group. Antibody to hGH was observed in 14.8% of the patients at the end of the first year of treatment, however the incidence was decreased to 4.7% by the end of the second year of treatment. Otherwise, there were no significant changes detected in physical or laboratory tests. No glucose intolerance necessitating treatment was observed. These results indicate that hGH treatment is useful in accelerating growth in patients with Turner's syndrome.

Adolescent↗
PubMed1989

Turner's syndrome: treatment of 203 patients with recombinant human growth hormone for one year. A multicentre study.

A total of 203 patients with Turner's syndrome were treated with three different kinds of recombinant hGH preparations for one year. One hundred and seven patients were treated with hGH at a weekly dosage of 0.5 IU/kg, 71 with 1.0 IU.kg-1.week-1, and the remaining 25 patients with combined administration of 0.5 IU.kg-1.week-1 hGH and a small amount of anabolic steroid. All three treatment groups showed statistically significant growth increases during the treatment. Fifty percent of the patients treated with 0.5 IU.kg-1.week-1 and 80% of the patients treated with 1.0 IU.kg-1.week-1 showed growth rates more than 2 cm per year greater than pretreatment values or beyond the second SD of the untreated growth rate. Plasma somatomedin C levels were elevated and no remarkable advances in bone age were observed during the treatment. Antibody against hGH was observed in 71.4% and 10.8% of the methionyl-hGH and methionine-free-hGH treated patients, respectively. However, the antibodies did not suppress the growth promoting effect of methionyl-hGH. Otherwise, there were no significant changes in physical or laboratory examinations. No glucose intolerance was observed. These results indicate that hGH treatment is useful for the acceleration of growth velocity in patients with Turner's syndrome.

Adolescent↗
PubMed1989

Measurement of nocturnal urinary growth hormone values.

Nocturnal urinary growth hormone values were measured by a sensitive enzyme immunoassay in normal adults, patients with GH deficiency, patients with Turner's syndrome, normal but short children who had normal plasma GH responses to provocative tests, and patients with acromegaly. The mean nocturnal urinary GH values in patients with acromegaly were significantly greater than those in normal adults (1582.3 +/- 579.8 vs 53.5 +/- 8.6 pmol/mmol creatinine (+/- SEM); p less than 0.05). In the normal but short children and patients with Turner's syndrome, the mean nocturnal urinary GH values were 83.1 +/- 5.2 and 79.8 +/- 29.5 pmol/mmol creatinine, respectively. In patients with GH deficiency, the nocturnal urinary GH values were undetectable (less than 5.3 pmol/mmol creatinine) except in one patient where the value was 6.3 pmol/mmol creatinine. The nocturnal urinary GH values of the patients with GH deficiency were significantly lower than those of the other groups (p less than 0.05). In normal but short children, the nocturnal urinary GH values correlated significantly with mean plasma nocturnal GH concentrations (r = 0.76, p less than 0.001), and 24-hour urinary GH values (r = 0.84, p less than 0.001), respectively. In 4 patients with GH deficiency who had circulating anti-hGH antibody, the urinary GH values were also undetectable. These data indicate that nocturnal urinary GH value reflects endogenous GH secretion during collection time, and that measurement of the nocturnal urinary GH values is a useful method for screening of patients with GH deficiency and acromegaly.

Acromegaly↗
PubMed1989

[Cardiac surgery of tetralogy of Fallot associated with DiGeorge syndrome: a case report].

A case of 7-year-old boy with tetralogy of Fallot associated with DiGeorge syndrome was reported. He had been diagnosed as cardio-facial syndrome with hypoparathyroidism because of hypocalcemia, convulsion, cardiac defect and the characteristic face. But immunologic study showed hypofunction of cellular immunity and cardiac catheterization and angiogram revealed the Tetralogy of Fallot. So we diagnosed as DiGeorge syndrome and performed operation. The thymus was not found and we close the ventricular defect with patch and reconstructed right ventricular outflow tract with transannular patch. We often measured serum ionized calcium level and corrected with calcium gluconate intravenously. Peritoneal dialysis was done due to oliguria and much inotropic support was necessary.

Child↗
PubMed1989

[Differences in CT findings between embolic and thrombotic cerebral artery occlusion of the internal carotid arterial system].

Two hundred and one patients with embolic (EM) and 107 with thrombotic (TH) cerebral arterial occlusion of the internal carotid arterial system were subjected to the study. Diagnoses of EM and TH were made with our own diagnostic criteria, based on clinical and angiographic informations but not on CT findings, as previously described. Well-marginated hypodense areas in multiple vascular territories were observed only in patients with EM (13.9%). The following CT findings were more frequently seen in EM than in TH; a) a hypodense area involving the cortex, b) a sharply-marginated lesion, c) a shift of the mid-line structures and d) hemorrhagic infarction. Patients with TH were more frequently accompanied with watershed infarction, or infarct in the basal ganglia and/or deep white matter than those with EM. Watershed zone between cortical and perforating arteries was involved only by TH. Deep-seated infarct, however, was more likely to be embolic rather than thrombotic in nature, if it was sharply-marginated and accompanied with surrounding brain edema. Differences in CT findings of EM and TH appeared to reflect those of pathogenetic mechanisms such as rapidity of occlusive process, sites of occlusion, routes and availabilities of collateral circulation, presence of reopening of the previously occluded artery, etc. In the present study, it can be concluded that there is distinctive differences in CT findings between EM and TH, indicating the usefulness in differentiation of two diagnostic subtypes in the acute stage of cerebral infarction.

Arterial Occlusive Diseases↗
PubMed1989

[Pulmonary artery aneurysm-like associated with pulmonary stenosis].

A 55-year old man had complained shortness of breathing and an abnormal shadow at left hilus region had been pointed out on the chest X-ray film. Right heart catheterization and right ventriculography revealed pulmonary valve stenosis with pulmonary artery aneurysm-like. Utilizing cardiopulmonary bypass, aneurysmorrhaphy and valvotomy was performed. Postoperative course was good and he was discharged on the 29th postoperative day. It is considered that mild post-stenotic dilatation of pulmonary trunk due to pulmonary valvular stenosis might develop into the aneurysmal change because of some congenital structural deficiency in the pulmonary arterial wall.

Aneurysm↗
PubMed1989

[A case report of aneurysm of the sinus of Valsalva due to infectious endocarditis with ASR].

A case (56 year-old, female) of the aneurysm of sinus of Valsalva due to infectious endocarditis with aortic stenosis and regurgitation was described. The patient was successfully operated upon by patch closure of the orifice of the aneurysm and aortic valve replacement with Medtronic Hall 23A. Post operative course was uneventful and discharged from the hospital at 37 post operative days in good condition.

Aortic Aneurysm↗