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Biomedical subjects

Y Harada

Publications and source records attributed to Y Harada.

At least 469 records · Page 26Linked to original sources
PubMed1991

Transantral ligation of the maxillary artery for refractory epistaxis. A case report.

A case of severe arterial epistaxis treated by transantral ligation of the maxillary artery is reported. A 66-year-old woman had recurrent left sided epistaxis from the posterior nasal cavity which was difficult to control by conventional nasal packing methods. Selective angiography was performed to identify the arterial flow patterns and site of bleeding which was confirmed to be the descending palatine artery. Following radiographical examination, ligation and clipping of the maxillary artery and its branches was performed with transantral approach under general anesthesia. No further epistaxis occurred after the ligation. This surgical procedure seems to be relatively simple and highly effective in the management of refractory epistaxis.

Aged↗
PubMed1991

[Successful mitral valve replacement in osteogenesis imperfecta--a case report].

A 34-year-old man with osteogenesis imperfecta who underwent successful mitral valve replacement due to mitral regurgitation was reported. Cardiac disease associated with osteogenesis imperfecta is very rare and only fifteen patients were operated under the extracorporeal circulation previously. While excessive hemorrhage due to tissue fragility was observed in 7 of 15 patients, perioperative course of the case reported here was completely uneventful. The difference of hemorrhagic tendency as well as etiology of osteogenesis imperfecta will be defined according to the advance of technology in collagen genetics and biochemistry in future.

Adult↗
PubMed1991

[Effect of age on visualization of right atrium by thallium-201 myocardial scintigraphy].

With Thallium-201 (Tl) myocardial scintigraphy, right atrial (RA) myocardium has been visible in the disease involving the right side of the heart. We have found RA visualization in the elderly patients without the evidence of right heart disease. Therefore, we studied the relation of age to the RA visualization with Tl myocardial scintigraphy performed at rest. Planar images of 291 patients without valvular or congenital heart disease were read by two observers and classified into the three by the degree of RA visualization; RA 0 = not visualized, RA 1+ = moderately visualized, RA 2+ = intensely visualized. The results were as follows: 93.1% of under 50 y.o., 77.8% of fifties, 86.7% of sixties, 50.5% of seventies and 36.7% of over 80 y.o. showed RA 0. 6.9% of under 50 y.o., 22.2% of fifties, 8.3% of sixties, 46.5% of seventies and 36.7% of over 80 y.o. showed RA 1+. None of under 60 y.o., 5.0% of sixties, 3.0% of seventies, and 26.6% of over 80 y.o. showed RA 2+. In conclusion, RA visualization in Tl myocardial scintigraphy, suggesting right heart overload, may increase with aging.

Aged↗
PubMed1991

Three dimensional intracellular structure of the cochlea using the A-O-D-O method.

We have observed the three-dimensional intracellular structure of the organ of Corti and the spiral ganglion of the chinchilla using the aldehyde osmium-DMSO-osmium (A-O-D-O) method, and compared our findings with previous studies in the guinea pig. In cells of the spiral ganglion and the organ of Corti, microtubules and other cytoplasmic filaments were digested by OsO4 during processing to provide a clear view of membranous structures such as mitochondria, endoplasmic reticulum and Golgi apparatus. The appropriate digestion time with 0.1% OsO4 solution was found to be 60-80 hrs for the organ of Corti and 70-90 hrs for the spiral ganglion. The A-O-D-O method has been especially useful to show the organization of the endoplasmic reticulum of the outer hair cells. We have made a further characterization of the apical cistern, a reticular network which appears to link the basal body of the (vestigial) kinocilium to both Hensen's body and the subsurface cisternae.

Animals↗
PubMed1991

[Effect of short-term administration of medroxyprogesterone acetate on side reactions of combination chemotherapy with ADR, VDS and CDDP in primary lung cancer].

The effect of short-term (10 days) Medroxyprogesterone acetate (MPA) administration on side reactions of combination chemotherapy with ADR, VDS and CDDP for primary lung cancer was studied by comparisons of MPA administration group (20 cases) with non administration group (30 cases). 1) Frequency of vomiting, duration of nausea and body weight loss were significantly improved in MPA administration Group (p less than 0.01). 2) Leukocyte and neutrophil counts in MPA administration group especially 7-10 days after of chemotherapy were maintained higher than these of non administration group (p less than 0.05). 3) Major side effects including thromboembolism in MPA administration group had not been observed. These results indicated that short-term MPA administration was relatively safe and effective in combination chemotherapy including CDDP.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1991

[The clinical significance of reverse redistribution of Tl-201 SPECT at rest in the 1st month after the onset of acute myocardial infarction].

The pattern of Thallium-201 reverse redistribution (r-RD) at rest has been reported in some patients with acute myocardial infarction (AMI) in the acute phase. But there is no report of this pattern in the later phase. To investigate the significance of Thallium-201 reverse redistribution in the subacute phase, 37 patients with AMI underwent Thallium-201 SPECT at rest a month after the onset. The patients were classified into three groups visually and 19 of 37 patients (51%) showed the persistent defect pattern (Group PD), and the remaining 18 patients (49%) had the reverse redistribution pattern (Group r-RD). None of them had the redistribution pattern. Coronary reflow was earlier and the incidence of the scintigraphic overlap on Dual SPECT image of 99mTc-PYP/201TlCl in the acute phase was more frequent in Group r-RD than in Group PD. A decrease in thallium defect size of patients with r-RD from the acute phase to one month after the onset represented improvement more significantly than that with PD. Initial %Tl uptake of the infarcted region of Group r-RD was greater than that of Group PD. The degree of stenosis of the infarct-related coronary artery in Group r-RD was less severe than that in Group PD. And corresponding regional wall motion of Group r-RD was less impaired. The Thallium-201 washout in the infarcted region with r-RD was significantly faster than that in the normal region. It is concluded that the r-RD pattern at rest in the 1st month after the onset of AMI may be a sign of viable myocardium.

Aged↗
PubMed1991

[Clinical and cytological features of acute myelogenous leukemia with 8; 21 chromosome translocation].

Eight cases of acute myelogenous leukemia with (8; 21) translocation were reported. As recently reported, they showed following features: M2 morphology in FAB classification (all 8 patients), abnormal granulocyte maturation, i.e. large granules and pseudo Pelger-Huet forms (5), Auer rods (8), occasional eosinophilia (2), frequent loss of one sex chromosome (5), the low neutrophil alkaline phosphatase activity (5), and tumor formation (one). Both CD13 and CD33 antigens were expressed on smaller number of leukemic cells than the other AML (M2) cells, whereas CD34 and HLA-DR antigens were expressed on higher number of cells. Interestingly CD19 antigen was detected on a small to large population of tumor cells from four out of six patients. Despite the high remission rate, many of them relapsed within one year. More intensive postinduction and maintenance therapy should be considered for those patients.

Adolescent↗
PubMed1991

[Ipsilateral synchronous renal pelvic transitional cell carcinoma and renal cell carcinoma: a case report and review of the literature].

A case of ipsilateral transitional cell carcinoma of left renal pelvis and left-renal cell carcinoma is presented. A 75-year-old male consulted our hospital with the complaint of painless gross-hematuria which had persisted for four years. Excretory urography revealed left non-visualized kidney. Retrograde pyelography demonstrated the filling defect, which had an irregular border, in the left renal pelvis. The selective left renal arteriography revealed the hypervascular region in the left renal cortex. Intraarterial chemotherapy with CDDP, MTX and ADR was performed preoperatively. Then, total left nephroureterectomy and segmental resection of the bladder was done. The surgical specimen was pathologically diagnosed as transitional cell carcinoma of the renal pelvis and renal cell carcinoma of the left kidney. This case is the 23rd reported case of ipsilateral synchronous renal malignancy in Japan.

Aged↗
PubMed1991

Target-dependent hormonal control of neuron size in the rat spinal nucleus of the bulbocavernosus.

The spinal nucleus of the bulbocavernosus (SNB) in the rat is a cluster of sexually dimorphic motoneurons that innervate perineal muscles. In adult male rats, the size of SNB neurons is reduced following castration, and this effect is reversed by treatment with testosterone. However, androgen receptors are present in the perineal muscles as well as in SNB neurons. Therefore, it is not clear whether the neuronal size is regulated by direct action of the hormone on SNB neurons or by a target-derived factor that may be controlled via hormonal action on the innervated muscle. To address this question, the peripheral (pudendal) nerve of SNB neurons on one side was cut and united to the grafted soleus muscle, which lacks androgen sensitivity. On the control side, the pudendal nerve was similarly cut but was allowed to reinnervate the perineal muscles. The size of SNB neurons was measured on both sides after a postoperative period of 10 weeks, during which the animal had been castrated or treated with testosterone after castration. The size of SNB neurons that had reinnervated perineal muscles was reduced following castration and enlarged by testosterone treatment. In contrast, the size of SNB neurons that had innervated the soleus muscle remained unaltered in response to testosterone manipulation. It is concluded that hormonal regulation of the size of SNB neurons in adult rats is mediated by their target muscles.

Animals↗
PubMed1991

[An emergent aortic and mitral valve replacement for active infective endocarditis preoperatively using extracorporeal ultrafiltration method].

We reported a 29-year-old man with active endocarditis complicating aortic and mitral valve regurgitation. The echocardiogram showed a mycotic aneurysm at aortic valvular annulus and a aneurysm of mitral valve. Heart failure was progressive and caused anuria. Prior to emergent double valve replacement, 2,500 ml of water was removed. Then hemodynamics became stationary. Urination was good during and after operation. In this case, complicating acute renal failure, dehydration with extracorporeal ultrafiltration method was very effective for improvement of hemodynamics.

Adult↗
PubMed1990

Cloning and sequence analysis of mink growth hormone cDNA.

A cDNA clone for mink growth hormone (GH) was isolated from a mink pituitary cDNA library, employing a part of rat growth hormone cDNA sequence as a probe. According to the nucleotide sequence, mature mink GH consists of 190 amino acids with a calculated molecular weight of 21,720. The amino acid sequence homology between the mature region of mink GH and those of pig GH, rat GH, bovine GH and human GH was 98.4%, 93.7%, 89.0% and 66.7%, respectively.

Amino Acid Sequence↗
PubMed1990

Evolutionarily stable stalk to spore ratio in cellular slime molds and the law of equalization in net incomes.

The evolutionarily stable stalk ratio (ESSR) in the cellular slime molds is studied when the fruiting body is formed by multiple clones of various size. The survival probability of a spore cell is assumed to depend on the stalk ratio and the fruiting body size. ESSR is obtained as the non-co-operative equilibrium (Nash solution) that maximizes the fitness of each clone. The following two predictions are obtained: (1) the number of spore cells produced by each clone forming a fruiting body tends to be equalized, even if a variation in clone size exists. As a result, the larger clones do not necessarily enjoy higher fitness than the smaller ones. (2) The stalk ratio and the overall fitness of the fruiting body decrease as the genetic diversity in the fruiting body increases. A condition for the stalk to spore ratio to be invariant of overall fruiting body size is also investigated. Finally, "the law of equalization in net incomes" is proposed, extending result (1) into the broader range of resource allocation problems.

Adaptation, Physiological↗
PubMed1990

Mechanochemical coupling in actomyosin energy transduction studied by in vitro movement assay.

In order to study the mechanochemical coupling in actomyosin energy transduction, the sliding distance of an actin filament induced by one ATP hydrolysis cycle was obtained by using an in vitro movement assay that permitted quantitative and simultaneous measurements of (1) the movements of single fluorescently labeled actin filaments on myosin bound to coverslip surfaces and (2) the ATPase rates. The sliding distance was determined as (the working stroke time in one ATPase cycle, tws) x (the filament velocity, v). tws was obtained from the ATPase turnover rate of myosin during the sliding (kt), the ATP hydrolysis time (delta t) and the ON-rate at which myosin heads enter into the working stroke state when they encounter actin (kON); tws approximately 1/kt-delta t-1/kON. kt was estimated from the ATPase rates of the myosin-coated surface during the sliding of actin filaments. delta t has been determined as less than 1/100 per second, kON was estimated by analyzing the movements of very short (40 nm) filaments. The resulting sliding distance during one ATP hydrolysis cycle near zero load was greater than 100 nm, which is about ten times longer than that expected for a single attachment-detachment cycle between an actin and a myosin head. This leads to the conclusion that the coupling between the ATPase and attachment-detachment cycles is not determined rigidly in a one-to-one fashion.

Actins↗