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Biomedical subjects

K Miwa

Publications and source records attributed to K Miwa.

At least 397 records · Page 22Linked to original sources

Construction of novel shuttle vectors and a cosmid vector for the glutamic acid-producing bacteria Brevibacterium lactofermentum and Corynebacterium glutamicum.

Novel cloning vectors for glutamic acid-producing bacteria have been constructed. Two cryptic plasmids, pAM330 from Brevibacterium lactofermentum and pHM1519 from Corynebacterium glutamicum, were used as precursors, and recombined with pBR325 or pUB110. Resultant composite plasmids were able to propagate and to express the CmR or KmR phenotype in B. lactofermentum and C. glutamicum. A smaller, high-copy-number plasmid, pAJ43, was also isolated following deletion of a part of the pAM330-pBR325 composite plasmid. Furthermore, a cosmid vector, which can be packaged and transduced through phage infection, has been developed using a cohesive-end fragment of the f1A phage and plasmid pAJ43. These plasmids are suitable for use as cloning vectors in the glutamic acid-producing bacteria.

Brevibacterium↗

The regional difference of relaxations induced by various vasodilators in isolated dog coronary and mesenteric arteries.

Relaxant responses to vasodilators, including nitroglycerin, sodium nitroprusside, prostaglandin I2 sodium salt (PGI2), prostaglandin E1 (PGE1), diltiazem hydrochloride and adenosine, were compared in helical strips of dog coronary arteries of different sizes and in coronary and mesenteric arterial strips. The relaxant responses to nitroglycerin, sodium nitroprusside, diltiazem and adenosine were significantly greater in coronary arteries than in mesenteric arteries, whereas the responses to PGI2 and PGE1 in these arteries did not significantly differ. In coronary arteries of different sizes, the relaxation induced by nitroglycerin was in the order of large greater than medium greater than small-size, while in contrast, the relaxations by adenosine, PGI2 and PGE1 were greatest in the small-size arteries and least in the large-size arteries. The relaxant responses to sodium nitroprusside and diltiazem did not differ in the coronary arteries of different sizes. Nitroglycerin, sodium nitroprusside and diltiazem appear to dilate coronary arteries more predominantly than mesenteric arteries. The preferential dilator action of PGI2 and PGE1 on distal coronary arteries, like that of adenosine, may lead more blood to re-distribute to the non-ischemic region of the heart in anginal patients.

Adenosine↗

Determination of the complete nucleotide sequence of the Brevibacterium lactofermentum plasmid pAM330 and the analysis of its genetic information.

The complete nucleotide sequence of the plasmid pAM330 derived from Brevibacterium lactofermentum ATCC 13869 was determined using the dideoxy chain termination method. Analysis of the sequence allowed us to observe seven open reading frames, one of which showed the presence of the promoter and the Shine-Dalgarno (SD) sequences upstream from the initiation codon.

Base Sequence↗

[The significance of the measurement of a serum gonadotropin-like substance in gastric cancer].

The serum concentration of hCG and CEA in 277 gastric cancers was extensively studied. 8.6% for hCG and 18% for CEA were regarded as positive. 9.4% of patients showed elevated serum level for both hCG and CEA, on the other hand 7% of the patients showed high hCG only. All of hCG positive patients had severe lymph nodal involvement. All cases of hCG positive and 85% of CEA positive cases were classified as stage 4. Macroscopically, 85% of hCG positive cases and 40% of CEA positive cases showed generalized type. Histological type was poorly differentiated adenocarcinoma in 72% of tumors with elevated serum hCG level, but in only 35% of tumors with elevated serum CEA level. The content of hCG subunits in serum and tumor showed different levels among patients. The hCG positive cases did not reveal endocrine symptom. The prognosis of these patients with elevated serum hCG and CEA level were poor. One year survival rates were 0% and 30%, respectively. These results showed that both hCG and CEA, especially when used in combination, was potentially useful marker for determination of staging, recurrence and prognosis in gastric cancer.

Carcinoembryonic Antigen↗

[The clinical and pathologic correlations in acute cholangitis].

The liver histology of acute cholangitis was studied in order to determine whether microscopic changes correspond to clinical status. Patients with acute cholangitis were divided into mild cholangitis (1st group, n = 18) and severe cholangitis (2nd, 3rd and 4th groups) accompanied by hypotension. The 2nd group consisted of 6 surviving patients who underwent liver biopsy during hypotension. The 3rd group consisted of 3 non-surviving patients with biopsy during hypotension. The 4th group consisted of 7 patients with biopsy during autopsy. The frequency of endotoxemia, gram negative bacteremia, disseminated intravascular coagulopathy and hepatic failure were significantly higher in severe cholangitis than in mild cholangitis. The incidence of neutrophilic infiltration in the sinusoid and microabscess in lobule were significantly higher in severe cholangitis than in mild one. The incidence of portal thrombosis and massive necrosis of hepatic cells were also significantly higher in severe cholangitis, especially in the 3rd and 4th groups. It was suggested that the neutrophilic infiltration in the sinusoid and microabscess in lobules which proved the existence of endotoxemia or bacteremia were characteristic findings in severe cholangitis.

Acute Disease↗

Novel host-vector system for selection and maintenance of plasmid-bearing, streptomycin-dependent Escherichia coli cells in antibiotic-free media.

A novel system for selection and maintenance of cells carrying a recombinant plasmid has been developed, using the streptomycin-dependent (Smd) Escherichia coli 4D host and a plasmid vector carrying an rpsL gene from an Sm-resistant (Smr) mutant of E. coli which masks the Smd phenotype. Strain 4D carrying the Smr pBR322 plasmid can grow without Sm. Using this host-vector system, we can select for cells carrying an Smr recombinant plasmid and maintain them in antibiotic-free media.

Bacterial Proteins↗

Secretory granules in benign and malignant glucagonomas of the pancreas.

Two cases of glucagonoma, one benign and the other malignant, was presented. Benign glucagonoma in a 29-year-old man with multiple endocrine neoplasia type 1 was composed largely of tumor cells with secretory granules ranging from 139 to 417 nm in diameter identical to A cell granules. There were a few tumor cells which contained no A cell granules but smaller granules of approximately 166 nm diameter similar to those of pancreatic polypeptide containing cells. Radioimmunoassay of the tumor extract showed 319 micrograms/g wet weight of glucagon and 0.72 microgram/g wet weight of pancreatic polypeptide. Malignant glucagonoma in a 34-year-old man was a massive tumor of 7 X 6 X 5 cm replacing the tail and body of the pancreas with multiple metastases. The tumor contained 0.2 microgram/g wet weight of glucagon and 0.065 microgram/g wet weight of vasoactive intestinal peptide. The electron microscopic examination revealed that the tumor cells had variable numbers of atypical secretory granules measuring 110 to 200 nm in diameter different from A cell granules. An analysis of plasma glucagon by the gel filtration technique showed the heterogeneity of glucagon molecules indicating the presence of large glucagon. Atypical secretory granules in malignant glucagonoma were considered to represent immature granules containing the precursor or intermediate of glucagon.

Adenoma, Islet Cell↗

Regional differences in the response to vasoconstrictor agents of dog and monkey isolated coronary arteries.

Contractile responses to vasoconstrictor agents were compared in helical strips of dog and monkey epicardial coronary arteries of different sizes. Contractions of large, medium and small arteries induced by KCl ( 30mM ) were virtually identical. Contractions induced by 5-hydroxytryptamine (5-HT) (10(-9) - 2 X 10(-6) M) were in the order of large greater than medium greater than small arteries in dogs, and large = medium greater than small arteries in monkeys. Cinanserin suppressed these responses. In contrast, contractions produced by angiotensin II (AII) (10(-7) M) were in the order of small greater than medium greater than large arteries in dogs, and small greater than medium = large arteries in monkeys. Sar1-Ala8-angiotensin II markedly attenuated the peptide-induced contractions. Contractions induced by prostaglandin F2 alpha (PGF2 alpha) were significantly greater in large and medium sized arteries than in small arteries in dogs, while those of the arteries of different sizes isolated from monkeys did not differ. Contractions induced by carbocyclic thromboxane A2 (c-TXA2), in arteries of different sizes in dogs and monkeys, did not differ. These results suggest that the sensitivity and/or the population of 5-HT receptors are greater in proximal coronary arteries than in distal arteries, while, in contrast, the sensitivity and/or population of AII receptors are greater in distal coronary arteries. Receptors for PGF2 alpha and c-TXA2 appear to react to a similar degree in monkey arteries of different sizes, although receptors for PGF2 alpha appear to be fewer in distal coronary arteries in dogs.

Angiotensin II↗

Amelioration of diabetes mellitus in partially depancreatized rats by poly(ADP-ribose) synthetase inhibitors. Evidence of islet B-cell regeneration.

Ninety percent depancreatized rats received daily intraperitoneal injection of 0.5 g/kg nicotinamide and 0.05 g/kg 3-aminobenzamide, potent inhibitors of islet poly(ADP-ribose) synthetase. One to three months after the partial pancreatectomy, urinary and plasma glucose levels in nicotinamide- and 3-aminobenzamide-treated rats were markedly lower than those in saline-treated control rats. Morphologic examination of the remaining pancreata revealed that islets in the poly(ADP-ribose) synthetase inhibitor-treated rats were markedly enlarged and consisted largely of B-cells. These results suggest that poly(ADP-ribose) synthetase inhibitors induce islet B-cell regeneration, thereby preventing or improving diabetes mellitus in partially depancreatized rats.

Animals↗

[Morphological and immunocytochemical studies of pancreatic multiple endocrine neoplasia type-1].

Morphological and immunocytochemical studies of pancreatic material from a patient with multiple endocrine neoplasia type-1 revealed hyperplasia of islets, multiple microadenomas, adenomas and cancers. Cellular composition of the hyperplastic islets was almost normal but the enlargement of the size and increase of the numbers were observed. Furthermore, neoformation of islets from ducts were found here and there. These hyperplastic islets, microadenomas, adenomas and cancers merged into each other and some of these microadenomas demonstrated malignant pictures. Most of the microadenomas produced multiple peptide hormones, on the other hand some of these revealed a single hormonal activity. These results show that the abnormality of the primordial cells of the pancreatic endocrine cells develops these lesion.

Adenoma↗

[The pathogenesis of diabetes produced by subtotal pancreatectomy, with special reference to the cell kinetics of the islet cells].

The pathogenesis of the diabetes produced by the subtotal pancreatectomy was investigated from the pancreatic endocrine function and the cell kinetics of the islet cells. The authors prepared the following two groups in the rats. The first group was 90% pancreatectomized rats and the second group was the 60% pancreatectomized rats. Most of the 90% pancreatectomized rats developed diabetes twelve weeks after operation. In these diabetic rats the insulin secretion was undetectable during glucose infusion. To the contrary, the relative increase of the glucagon secretion was found during arginine infusion in spite of the hyperglycemia. However, non of the 60% pancreatectomized rats developed diabetes during post-operative course up to 6 months. To investigate the cell kinetics of the islet cells, the 3H-thymidine autoradiography was prepared at several intervals after operation. The results of the thymidine labelling index showed two phase of regeneration. The first phase was observed on three to seven days after pancreatectomy and the second phase was on fourteen to twenty-eight days. After the second phase of regeneration, the degeneration of the B-cells was observed in the 90% pancreatectomized rats. On the ninetieth days after operation the atrophy of the islets and the disturbance of the arrangement of A, B and D cells were observed by the immuno-histochemical studies. Meanwhile, the 60% pancreatectomized rats did not show degeneration of the islets. These results show that the onset of diabetes after subtotal pancreatectomy was produced by degeneration of the B cells surpassing their regenerative capacity.

Animals↗

Evaluation of the TNM classification of stomach cancer and proposal for its rational stage-grouping.

The present TNM Classification with the provisional stage-grouping for stomach cancer, which was adopted in 1978, was evaluated for compatibility in respect to survival by using 15,589 stomach cancer patients registered in Japan from 1969 to 1973. Adequacy and usefulness were shown in all categories of T, N, M, pT and pN, individually. Important irrationality in accordance with the TNM General Rules was recognized in both the provisional TNM and p.TNM stage-groupings. More adequate stage-grouping was searched for and is discussed according to the results of statistical analysis of the patients' survival and the principle of the TNM General Rules. New TNM and p.TNM stage-groupings were proposed as the best ones at present.

Biometry↗

[A case of gastric carcinoid associated with multiple early gastric cancers and atypical epithelium].

A 69-year-old man was admitted to our hospital complaining of the sensation of abdominal fullness and tarry stool. X-ray and endoscopic examination revealed a gastric tumor measuring 6.5 X 7.5 cm in the antrum along the greater curvature. Histologically, the tumor was diagnosed as carcinoid; five lesions of early gastric cancer and one lesion of atypical epithelium were also detected. Through 1982, 24 Japanese patients with gastric carcinoid associated with gastric cancer have been reported.

Adenocarcinoma↗

Intracystic carcinoma of the breast in an elderly man.

An eighty year old man with a mass in the left breast visited our department on October 27, 1980. Examination disclosed a smooth surfaced, round, elastic soft, 3 cm in diameter sized, non-tender mass underneath the left nipple. Mammogram showed a well defined oval opacity and echogram showed a cystic lesion. The mass was punctured and dark brown fluid was aspirated, but there were no malignant cells. The cyst was extirpated and a rice grain sized mass was found in the cyst wall. Histologically, it was diagnosed as non-infiltrating medullary tubular carcinoma. On November 27, 1980, simple mastectomy revealed no histological evidence of a residual cancer.

Adenocarcinoma↗