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Biomedical subjects

K Goto

Publications and source records attributed to K Goto.

At least 1,027 records · Page 57Linked to original sources
PubMed1976

The effect of denervation on the synchronization of contraction of the rat vas deferens.

Denervation of the rat vas deferens results in both quantitative and qualtitative changes in the contraction of the isolated smooth muscle. The maximum contraction induced by norepinephrine, acetylcholine or serotonin is enhanced by denervation. The response of the tissue to 2 X 10(-4) M BaCl2 initiates a contraction which is more synchronized than the response of the control tissue. By use of 14C-sorbitol and Co-EDTA for estimating extracellular space and from fluorescence histochemical observations, it appears that facilitation of drug diffusion through the extracellular space plays an unimportant role in the altered response to drugs. In experiments which utilized a double-compartment tissue bath it was found that denervation enhanced the propagation of the contraction in the longitudinal direction. From measurements of the longitudinal tissue impedance it was determined that the resistance between smooth muscle cells was significantly decreased by denervation. These results suggest that denervation improves the propagation of excitation in this smooth muscle.

Animals↗
PubMed1976

Antiarrhythmic action of a new beta-adrenergic blocking agent, 6-(2-hydroxy-3-isopropylaminopropyloxy)-benzothiazole succinate (KF-577), compared with that of propranolol.

The antiarrhythmic activity of a new beta-adrenergic blocking agent, 6-(2-hydroxy-3-isopropylaminopropyloxy)-benzothiazole succinate (KF-577), was compared with that of propranolol. KF-577 antagonized ouabain-induced arrhythmias in normal and bilaterally vagotomized guinea pigs; its antagonistic activity was equal to that of propranolol. Reserpinization greatly reduced ouabain intoxication and neither of the two beta-blockers produced further reduction. Aconitine-induced arrhythmias in rats were not antagonized by the two agents. In intact guinea pigs, the reduction of ouabain intoxication by both beta-blockers could not exceed that produced by simulataneous infusion of KCl, and vice versa. In isolated guinea pig atria, propranolol was about 10 times more effective than KF-577 in reducing the ouabain intoxication. The antiaarhythmic activity of KF-577 paralleled its beta-blocking activity in the isolated preparations but not in the intact animals.

Aconitine↗
PubMed1976

Electroencephalographic and clinicopathological studies on Creutzfeldt-Jakob syndrome.

The correlation between the appearance of the characteristic electroencephalographic abnormality, cardinal clinical manifestations, and neuropathological features was studied in four cases of Creutzfeldt-Jakob syndrome consisting of subacute spongiform encephalopathy and classical Creutzfeldt-Jakob disease. Consideration is given to the differences in the electroencephalographic findings between these two subgroups of the syndrome and on the underlying pathological mechanism.

Aged↗
PubMed1976

Duplication of the straight sinus. An angiographic study.

Duplication of the straight sinus is often noted in the venous phase of carotid angiograms. Since this vascular anomaly is rarely described in the literature, the authors present its incidence in a series of 700 cases, and consider its embryological origins and clinical significance.

Adolescent↗
PubMed1976

Serial cerebral angiography in stereoscopic magnification.

A ceiling x-ray tube support with synchronous up and down movements is described for obtaining two parallel x-ray beams with a short focal-film distance. Stereoscopic cerebral angiography is performed with direct serial magnification using a heavy-duty anode tube with a 0.1 mm focus. This technique combines the advantages of magnification and stereoscopic angiography. Small arterial and venous changes can be observed clearly in three dimensions. The usefulness and limitations of this method are discussed using clinical and experimental data.

Adult↗
PubMed1976

Partial purification of the ovarian oviposition-inducing factor and estimation of its chemical nature.

The ovarian ruptured follicles larger than 0.2 g. of wet weight were collected from laying hens and an ovarian oviposition-inducing factor (OOIF) was extracted from the follicles. The extract was chromatographed on a column of Sephadex G-75. Material from the active region for inducing premature oviposition was subjected to thioglycollate or trypsin treatment. It was found that oxytocic activity of this material was completely destroyed by thioglycollate buy not by trypsin, when tested on the contractility of the isolated hen's uterus. The OOIF was found to be diffusible through a cellophane bag. It is suggested that the OOIF may be a relatively small molecule have a disulfied bridge and it seems to be a hormone or hormone-like substance resembling the posterior pituitary hormones in the chemical nature.

Animals↗
PubMed1976

[Phonocardiographical studies in hypertensive subjects (author's transl)].

Phonocardiographical (PCG) studies were made to evaluate the relation of the PCG to blood pressure, ECG, chest X-ray finding and changes of fundi in hypertensive subjects. One hundred and thirty hypertensive patients and sixty normal adults were examined. Results were as follows: 1) There were abnormal second heart sounds such as, narrow splitting or ringing in most cases of hypertensive subjects with high both systolic and diastolic blood pressure. These phenomena seemed to be delay and accentuation of aortic component. 2) Ejection murmur was found in majority of constantly hypertensive cases. 3) The third and fourth sounds had no definite correlation to blood pressure. However, accentuation of the fourth sound was found only in subjects with severe myocardial changes in ECG. 4). Q-I time in hypertensive group was found to be prolonged as compared to normal. 5) In normal subjects, I-IIA interval was related closely to square root R--R. It was not clear in hypertensive group, and the most cases of this group showed that I-IIA interval was prolonged as compared to square root R--R. Prolonged I-IIA interval was seen in the group with only high voltage and no myocardial abnormality in ECG. In conclusion, characteristic phonocardiographical findings in hypertensive subjects were the prolonged mechanical contraction time involving isovolumic one and this time became shorter when myocardial damage was increased in its severity.

Adult↗
PubMed1976

[Partial fenestration of the basilar artery--report of a case (author's transl)].

A 44-year-old male entered the hospital following an episode of subarachnoid hemorrhage on January 28, 1975. The left vertebral angiography revealed an anteriovenous malformation in the mesencephalon mainly feeded by the thalamoperforate artery and the medial branch of the posterior choroidal artery. A partial fenestration of the basilar artery was also demonstrated. The patient refused the surgical treatment for the arteriovenous malformation and was discharged on March, 28, 1975. Fenestration of the basilar artery develops by arrested or abnormal development at the first and second stage of the embryological process. Most basilar artery fenestration demonstrated by brain dissection and angiography are cases of a short segment duplication (partial fenestration) while duplication of the entire segment of the basilar artery (complete fenestration) is quite rare. Only six cases of angiographically revealed basilar artery fenestration have been reported so far in the literature. With increasing application of vertebral angiography, this developmental anomaly may be encountered more frequently.

Basilar Artery↗
PubMed1975

Simple differential Giemsa staining of sister chromatids after treatment with photosensitive dyes and exposure to light and the mechanism of staining.

The essential steps of the 33258 Hoechst-Giemsa method for differential chromatid staining consist of (1) 33258 Hoechst treatment, (2) exposure to light, and (3) Giemsa staining. The staining was shown to be a function of the concentration of 33258 Hoechst and the light exposure. The dye was successfully replaced by various metachromatic dyes such as thionine. Two simple methods are proposed. Failure of the pale stained chromatids to restore Giemsa affinity with urea and trypsin and the diminished Feulgen reaction after light exposure suggest that not masking proteins but photolysis of the BrdU-incorporation chromatid components in the present of photosensitive dyes play a role in the differential staining.

Animals↗
PubMed1975

Effects of various denervation techniques on the ATP of the rat vas deferens.

Postganglionic denervation of the vas deferens of the rat by surgical means or pretreatment with 6-hydroxy-dopamine results in a substantial decrease in the concentration of ATP in the tissue. The loss of ATP cannot entirely be accounted for by the loss of neuronal ATP nor by a compromised blood supply. The results suggest that the postganglionic nerve plays an important role in the regulation of the ATP of the effector cells.

Adenosine Triphosphate↗
PubMed1975

Acute cytogenetic effect of 2-(2-furyl)-3-(5-nitro-2-furyl)-acrylamide (AF-2, a food preservative) on rat bone marrow cells in vivo.

The cytogenetic effects of 2(2-furyl)-3-(5-nitro-2-furyl)-acrylamide (AF-2), a food preservative used in Japan, on rat bone marrow cells in vivo were studied. The aberrant metaphase cells in the bone marrow increased and reached the peak level 6 h after intraperitoneal injection of 240 mg/kg body weight of AF-2 and returned to the normal level within 24 h. A dose-response relationship was obtained using 4-240 mg/kg of AF-2. Chromosome aberrations were also induced after oral administration of 30-240 mg/kg. The aberrations were mostly chromatid breaks and the distribution among and within chromosomes was similar to those induced by a carcinogen, 7, 12-dimethylbenz(a)anthracene (DMBA). The present results provide the first evidence of in vivo cytogenetic effects of AF-2 on mammalian cells and, together with the evidence of mutagenicity already proved in other organisms, warn of the possible genetic hazards to cells exposed to this compounds.

9,10-Dimethyl-1,2-benzanthracene↗