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Biomedical subjects

S Hara

Publications and source records attributed to S Hara.

At least 361 records · Page 20Linked to original sources

Reconstitution of new inhibitors through mutual exchange of Ile(64)-Met(84) peptides of soybean trypsin inhibitors, Tia and Tib.

Singly modified soybean trypsin inhibitors (STIs), Tia* [Tia cleaved at Arg(63)-Ile(64)] and Tib* [Tib cleaved at Arg(63)-Ile(64)], were prepared by limited proteolysis with trypsin at pH 3.0. These singly modified inhibitors were further modified to yield doubly modified inhibitors, Tia** and Tib**, by limited proteolysis with subtilisin BPN', which cleaved the Met(84)-Leu(85) bonds of Tia* and Tib*, respectively. The doubly modified inhibitors could be separated into two parts: protein moiety A and peptide moiety a (IRFIAEGHPLSLKFDS-FAVIM) for Tia**, and protein moiety B and peptide moiety b (IRFIAEGNPLRLKFDS-FAVIM) for Tib**. These protein and peptide moieties showed no trypsin inhibitory activities alone. However, the inhibitors can be reconstituted through the mutual exchange of the protein and peptide moieties isolated from STIs. The reconstituted inhibitor which has tyrosine at position 62 and histidine at position 71 shows the highest inhibitory activity. Its Ki value for bovine trypsin is around 10(-10) M, which is almost the same as that of Tia for bovine trypsin. The inhibitor possessing either tyrosine at position 62 or histidine at position 71 exhibits a Ki value of around 10(-9) M, which is between those of Tia and Tib. The inhibitor having phenylalanine and asparagine at positions 62 and 71, respectively, shows the weakest inhibitory activity of around 10(-8) M similar to that of Tib for bovine trypsin.

Amino Acid Sequence↗

Augmentation of prostaglandin E2 production by mammalian phospholipase A2 added exogenously.

Rat group II phospholipase A2 added exogenously to A23187-activated HL-60 granulocytes augmented their production of prostaglandin E2. Human group II phospholipase A2 and porcine group I phospholipase A2 augmented the prostaglandin E2 production in a similar manner. No significant increase in prostaglandin E2 production was observed when cells were treated with purified phospholipase A2 in the absence of A23187. Extracellular phospholipase A2 at inflamed sites may contribute to the generation of pro-inflammatory lipid mediators by hydrolyzing the cellular phospholipids of activated inflammatory cells.

Animals↗

The reactive site of marinostatin, a proteinase inhibitor from marine Alteromonas sp. B-10-31.

A new homologue of marinostatin, a peptide proteinase inhibitor, was isolated from marine Alteromonas sp. B-10-31 and designated as marinostatin D. Its amino acid sequence was determined to be Ala-Thr-Met-Arg-Tyr-Pro-Ser-Asp-Asp-Ser-Glu. The reactive site of marinostatin D was determined to be Met(3)-Arg(4) on the basis of the reversible cleavage and regeneration of the scissile bond catalyzed by TLCK-chymotrypsin.

Amino Acid Sequence↗

Macular choroidal occlusion in dysplasminogenemia.

The authors describe a family with dysplasminogenemia. This diagnosis was based on a lowered ratio of functional plasminogen activity to immunologic plasminogen antigen level, associated with fundus abnormalities. The proband is a 31-year-old woman with Graves disease who had choroidal occlusive lesions of the macula in both eyes. The results of the laboratory examination indicated that the patient was a homozygote for dysplasminogenemia. Similar examinations of the patient's parents and siblings showed their plasminogen levels to be 50% below normal. The thrombotic tendency in this disorder appeared to be responsible for the pathogenesis of the macular choroidal occlusion.

Adult↗

Different effects of paraquat on microsomal lipid peroxidation in mouse brain, lung and liver.

Paraquat stimulates NADPH-Fe(2+)-dependent microsomal lipid peroxidation in mouse brain and strongly inhibits it in the liver. In lung microsomes, the lipid peroxidation was stimulated by paraquat at 10(-4) M, but not at higher doses. An antioxidant action of paraquat seemed to account, at least in part, for the lack of stimulation in lung microsomes, but it was inappropriate to explain the result in hepatic microsomes. There was no apparent correlation between the effects of paraquat on the lipid peroxidation and on the activity of NADPH-cytochrome P-450 reductase, the enzyme which initiates redox cycling of paraquat, resulting in generation of active oxygen species. In fact, the effect of paraquat on the lipid peroxidation was independent of paraquat radical production, an intermediate in the cycle. However, the inhibitory potency of N-ethylmaleimide on NADPH-cytochrome P-450 reductase activity paralleled that on the lipid peroxidation stimulated by paraquat in brain and lung. These findings indicate that the effect of paraquat on microsomal lipid peroxidation differs among the organs and that other factors, besides NADPH-cytochrome P-450 reductase, might be involved in the stimulation of lipid peroxidation by paraquat.

Animals↗

Mechanism of paraquat-stimulated lipid peroxidation in mouse brain and pulmonary microsomes.

Paraquat-stimulated NADPH-dependent lipid peroxidation in mouse brain and pulmonary microsomes was inhibited by superoxide dismutase and singlet oxygen quenchers, but not by catalase or hydroxyl radical scavengers. MnCl2, which might form a salt with unsaturated lipid, inhibited the lipid peroxidation in brain microsomes, but not that in pulmonary microsomes. These findings suggest that activated oxygen species, especially superoxide and singlet oxygen, may play a major role in the stimulation of microsomal lipid peroxidation by paraquat in both brain and lung, and that the nature of the lipids exposed to peroxidative attack may be different in microsomes of the two organs.

Animals↗

Abundance of viruses in marine waters: assessment by epifluorescence and transmission electron microscopy.

Abundance of bacteria and tiny DNA-associated particles in the upper layer of Japanese coastal and offshore waters was evaluated by epifluorescence microscopy with 0.015-mum-pore-size Nuclepore filters. The number of tiny DNA-associated particles was compared with the abundance of virus particles estimated by transmission electron microscopy. Although a large variation in virus abundance (1.2 x 10 to 35 x 10 ml) was obtained with the transmission electron microscopy method, the ratio of 4',6-diamidino-2-phenylindole-reactive tiny particles to viruses was in a rather narrow range (1.0 to 1.6), indicating that the majority of the tiny DNA-associated particles identified by epifluorescence microscopy were actually virus particles. This result implies the possibility of using epifluorescence microscopy for the evaluation of virus abundance in marine environments.

Journal Article↗

Endopyelotomy for treatment of ureteropelvic junction obstruction.

A total of 14 patients underwent endopyelotomy at our institution for treating ureteropelvic junction (UPJ) obstruction (12 primary and 2 secondary obstructions) between March 1986 and July 1989. Radiographic evaluation of the patients with a minimum follow-up of 6 months demonstrated improvement in 11, while the remaining 3 were stable. These 3 were cases with primary obstruction and 2 of them had had an associated large redundant renal pelvis. No patients exhibited evidence of increased hydronephrosis or decreased renal function. Twelve of the 14 patients had had preoperative symptoms. Complete and partial remission of the symptoms was obtained in 11 and in 1 who was radiographically stable, respectively. Thus, our success rate for endopyelotomy was 75% in primary obstruction. Successful results were obtained in all the 2 cases with secondary obstruction. There was 1 patient with an intraoperative complication (extravasation) and a late complication related to the stent. However, the problems were minor and easily corrected. Our results suggest that careful selection of cases may lead to a high success rate in endopyelotomy for treating primary UPJ obstruction.

Adolescent↗

A case of extraadrenal pheochromocytoma with papillary thyroid carcinoma.

A 63-year-old housewife with a history of partial thyroidectomy was referred to our hospital because of a neck mass and abdominal tumor. Aspiration biopsy of the neck tumor revealed the recurrence of papillary thyroid carcinoma. Magnetic resonance imaging (MRI) of the abdomen and urinary and plasma catecholamine levels indicated that the tumor beside the abdominal aorta was an extraadrenal pheochromocytoma. Two tumors were excised and histologic studies confirmed the diagnosis. So far two cases of extraadrenal pheochromocytoma with papillary thyroid carcinoma have been reported. The present case indicates that the presence of papillary thyroid carcinoma should be considered in patients with extraadrenal pheochromocytoma.

Abdominal Neoplasms↗

[Vasitis nodosa: report of two cases].

Two cases of vasitis nodosa are reported hereon. The two patients were 47 and 40 year old males with desire of refertility. They were performed vasectomy 23 and 10 years ago. They were subjected to vaso-vasostomy. During the operations, spindle shaped nodules were found in the vas deferens at the site of the previous vasectomy. Histologically, they showed focal proliferation of epithelial components forming glands, where a plentiful number of sperms were present, and this was also associated with proliferative change of smooth muscle bundles of vas deferens. Some foci of spermatic granulomas were also found. This condition was similar those of salpingitis isthmica nodosa in the fallopian tube. Vasitis nodosa should be differentiated from metastatic adenocarcinoma histologically. This condition may lead to re-canalization.

Adult↗

The glucoamylase cDNA from Aspergillus oryzae: its cloning, nucleotide sequence, and expression in Saccharomyces cerevisiae.

A cDNA for Aspergillus oryzae glucoamylase was cloned, using oligodeoxyribonucleotide probes derived from amino sequences of peptide fragments of the enzyme. The glucoamylase cDNA, when introduced into Saccharomyces cerevisiae, directed the secretion of active glucoamylase into the culture medium. The complete nucleotide sequence of the cDNA contained an open reading frame encoding 612 amino acid residues. Comparative studies with other fungal glucoamylases showed homologies of 67% with A. niger and 30% with Rhizopus oryzae of the deduced amino acid sequences. In the five conserved regions reported in other fungal glucoamylases, the levels of homologies between those regions of A. oryzae and A. niger enzymes were much higher (78-94%). A. oryzae glucoamylase contained no peptide region abundant in threonine and serine residue (TS-region), like that proposed to adsorb onto raw starch in A. awamori var. kawachii glucoamylase.

Amino Acid Sequence↗

Cloning and nucleotide sequence of the KHS killer gene of Saccharomyces cerevisiae.

A 5.3-kbp fragment of the KHS gene was cloned from a genomic bank of Saccharomyces cerevisiae No. 115 constructed with an E. coli as the host and YEp13 as the vector. A non-killer yeast strain was transformed to a killer strain with the multi-copy vector containing the KHS gene, and the transformant could secrete 3-4 times more killer toxin into culture media than the donor, strain No. 115. The KHS toxin was purified 80-fold from the culture filtrate by gel filtration and column chromatography. The nucleotide sequence of a 2.8-kbp fragment of the KHS DNA that was enough for the expression of the killer activity was identified, and we found an open reading frame consisted of 2124 bp. Comparison of the open reading frame and N-terminal amino acid sequence of purified KHS toxin, suggested that the presumed peptide from the KHS gene might be processed between 36Gln and 37Ala before secretion.

Amino Acid Sequence↗

[An analysis of 70 patients with bilobectomy for bronchogenic carcinoma].

From 1955 to April 1989, 70 patients underwent bilobectomy for the treatment of primary lung carcinoma. Thirteen patients (18.6%) underwent right upper and middle lobectomy (UML), while 57 patients (81.4%) underwent right middle and lower lobectomy (MML). Indications for bilobectomy were cancer invasion into intermediate bronchus (34%), tumor extending to neighbouring lobe across a fissure (29%), interlobar lymph nodes metastasis with or without invasion to intermediate bronchus (24%), vascular invasion (5%), and others (7%). Squamous cell carcinoma was present in 31 patients, adenocarcinoma in 28, large cell carcinoma in 5, small cell carcinoma in 4 and others in 2. About 60 percent of the patients had Stage III or IV diseases. Postoperative complications occurred in 27 patients (38.6%) and 3 died within 30 days after operation (operative mortality rate. 4.3%). Pneumonia, empyema, atelectasis and arrhythmia were prominent postoperative complications. There were no statistically different postoperative complication rates between those with UML and those of MLL. Five-year survival rate of the patients with bilobectomy for lung cancer was 25.7%, which was between those with single lobectomy (36.9%) and those with pneumonectomy (5.6%). However, there was no statistical difference in 5-year survival rate among operative procedures in each stage.

Adenocarcinoma↗

[Lung function following sleeve bronchoplastic lobectomy for bronchogenic carcinoma].

Twenty-five patients who underwent upper sleeve lobectomy for lung cancer were studied by spirometric examination to evaluate postoperative pulmonary function, including Vital Capacity (VC), %Vital Capacity (%VC), Forced Expiratory Volume in one second (FEV1.0), and Forced Expiratory Volume in one second as a percentage of the forced vital capacity (FEV1.0%). The results of the patients with bronchoplasty were compared with those of patients with lobectomy alone and of patients with pneumonectomy. Lung function was periodically examined postoperatively following bronchoplasty. VC, %VC and FEV1.0 were decreased postoperatively in the patients with upper sleeve lobectomy, while FEV1.0% was increased. There were no differences in postoperative %VC or FEV1.0% between the patients with bronchoplasty and those with upper lobectomy alone. However, the postoperative %VC of the patients with pneumonectomy was significantly decreased compared with patients who underwent postoperative %VC of the patients with pneumonectomy was significantly decreased compared with patients who underwent bronchoplasty or lobectomy alone. %VC in the patients with bronchoplasty was decreased at 3 months after operation, but it to gradually returned to the preoperative value by 13 to 24 months after operation.

Adult↗

[Disseminated intravascular coagulation after transurethral ureterolithotripsy: a case report].

We experienced a case of disseminated intravascular coagulation (DIC) following transurethral ureterolithotripsy (TUL). A 78-year-old woman was referred to our hospital with the complaints of fever and urinary tract infection. Urine culture showed positive E. coli and antibiotics were given. Radiologic findings revealed a left renal stone. The patient underwent TUL. After the operation acute renal failure occurred. Laboratory data revealed DIC on the next day. In spite of intensive therapy the patient died. Pathological findings showed that acute renal failure was caused by DIC. It is important that we should note the risk of DIC after TUL.

Acute Kidney Injury↗

[Results of radical nephrectomy associated with regional lymphadenectomy for renal cell carcinoma].

Between January, 1975 and December, 1989, 86 patients with renal cell carcinoma received radical nephrectomy associated with lymphadenectomy at our institutions. Pathological examination revealed lymph node metastasis in 15 patients (17.4%). The incidence of lymph node metastasis increased in accordance with the aggravation of tumor stage (p less than 0.01) and grade (p less than 0.05). Patients with a rapidly growing tumor showed higher incidence of lymph node metastasis than patients with a slow growing tumor (p less than 0.01). Regional lymph node metastases were found in 3 of the 41 patients with a slow growing tumor. Since these 3 patients are surviving with no evidence of disease for 38.7 months on average, the regional lymphadenectomy was considered to have been effective for their survival. Nine of the 25 patients with a rapid growing tumor had progressive lymph node metastasis. Four of them had apparent tumor thrombi as well as lymph node metastasis, and 2 of them had distant metastasis. These patients showed poor prognosis even after operation. Lymphadenectomy was of no value to the patients with apparent tumor thrombi and/or distant metastasis.

Adult↗