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Biomedical subjects

M Shirai

Publications and source records attributed to M Shirai.

At least 199 records · Page 11Linked to original sources
PubMed1992

Sensitivity of the fetal rat pituitary-adrenal system to corticotropin-releasing factor in organ culture.

Six groups of adrenal glands from 17-day fetal rats were explanted to organ culture for 2 days. In one group, adrenal gland was cultured alone, and in the remaining five groups adrenal gland was cultured with pituitaries from fetuses ranging in age from 14 to 18 days. In each of the groups, half of the cultures had corticotropin-releasing factor (CRF) added to the medium. A histometric parameter utilized the size of adrenocortical cells as an indicator of sensitivity of the pituitary-adrenal system. When 17-day adrenal gland was cultured alone, addition of CRF did not cause any enlargement of cortical cells. When the adrenal gland was cultured with two 14-day pituitaries, cortical cells were enlarged. Addition of CRF to this culture induced no further change. With two 15-day pituitaries in the presence of CRF, cortical cells were slightly larger than those in the absence of CRF. With 16- to 18-day pituitaries, a marked hypertrophy of cortical cells was induced, and the addition of CRF caused further acceleration in their enlargement. These results suggest that, in organ culture, 14-day pituitary can release some adrenocorticotropic hormone (ACTH) with or without additional CRF. Older pituitaries (16- to 18-day) can apparently release an amount of ACTH in the presence of CRF that is greater than their own spontaneous ACTH secretion.

Adrenal Glands↗
PubMed1992

[Drug induced cystitis due to ketotifen fumarate--a case report].

Tranilast, an antiallergic drug, is well known as a causal drug of cystitis, and a report is made here of our experience of 1 case of drug-induced cystitis ascribable to ketotifen fumarate. A 13-year-old female had been taking anti-asthmatic drugs orally since the onset of athmatoid attacks, from age of 5. The attacks intensified from the age of 12, because of this she began to take various anti-asthmatic drugs orally. She visited another hospital, due to pollakisuria, in November, 1990, and received treatment for cystitis. However, the symptoms were not alleviated, and she visited our department on January 9, 1991. By urinalysis, large counts of leukocytes and erythrocytes were observed in a visual field of the sediment. Remarkable reddening was observed over the urinary bladder in the patient's cystoscopic findings. Treatment was given at our department, on an outpatient basis, with various antibacterial drugs for approximately one month, but her symptoms were not alleviated, pollakisuria and aseptic pyuria persisted. The patient had never taken tranilast; oral intake of ketotifen fumarate and saibokutou was discontinued on February 13, due to a suspicion of drug-induced cystitis, and her symptoms subsequently disappeared. On February 22, she took ketotifen fumarate orally again, on her own, due to asthmatoid attack, and her symptoms returned. The oral intake of ketotifen fumarate was again discontinued, and alleviation of the symptoms and normalization of the urinary findings were again observed. As a result, lymphocyte stimulation tests on all the drugs the patient had ever taken, only ketotifen fumarate turned out to be positive.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

[Bilateral multilocular cystic renal cell carcinoma].

A case of bilateral renal cell carcinoma with multilocular cysts is described. A 42-year-old female was admitted to our hospital for the purpose of further examination or right renal cystic mass discovered incidentally by ultrasonography. After she was examined by CT-scan and angiography, right nephrectomy was performed under the diagnosis of right renal cancer. Histological diagnosis was multilocular cystic renal cell carcinoma. One year later a small cystic legion was found in the left kidney. Under the diagnosis of left renal cancer, left partial nephrectomy was performed. Histological diagnosis was multilocular cystic renal cell carcinoma same as the right kidney. Multilocular renal cyst is classified into several classes by its style of development. This case of bilateral renal cell carcinoma which grew to be multilocular cysts is the first case in Japan as far as we can search.

Adult↗
PubMed1991

[Study of early gastric cancer in upper third area of the stomach (C-area)].

From January 1976 to March 1990, 802 cases of early gastric cancer (886 lesions) were underwent surgical resection at Himeji St. Mary's Hospital. Among them there were 74 cases (9.2%) of early gastric cancer (75 lesions (8.5%) in the C-area. In comparison with early gastric cancer found in the other 2 thirds of stomach, early gastric cancer in the C-area showed a higher incidence rate of the posterior wall lesions. This might be due to the reason why anterior wall lesions in the C-area were not fully displayed by routine radiological procedure. Since anatomically it is very difficult to study this area with the compression method, the thin layer method in the prone position should be recommended in addition to routine double contrast study.

Adult↗
PubMed1991

Effects of pirarubicin, an antitumor antibiotic, on the cardiovascular system.

In the present study we examined the effects of pirarubicin [(2"R)-4'-O-tetrahydropyranyladriamycin, THP] on a cardiovascular system. An injection of THP (0.39-3.13 mg/kg, i.v.) reduced the mean blood pressure and caused an increase in the respiratory air rate in anesthetized rats. At 1.5 x 10(-6)-1.5 x 10(-5) M, THP markedly relaxed a contraction induced by 10(-7) M norepinephrine in rat aorta with endothelium but not in that without endothelium. At a dose of 0.02-0.5 mg, THP produced an increase in the contractile force and the perfusion flow of isolated perfused guinea pig hearts. At a higher concentration (4.5 x 10(-5)-1.5 x 10(-4) M), it produced a slight increase in the contractile force of the left atria in guinea pigs. This positive inotropic action of THP was inhibited by diphenhydramine (10(-6)-5 x 10(-5) M), chlorpheniramine (3 x 10(-7)-3 x 10(-5) M), and tripelennamine (3 x 10(-7)-3 x 10(-5) M) but not by propranolol (10(-6) M), cimetidine (10(-5) M), diltiazem (10(-6) M), or ryanodine (10(-8) M). THP given i.v. at 2.5 mg/kg elevated the plasma histamine level in anesthetized dogs. From these data, we conclude that THP mainly relaxed the rat aorta in the presence of endothelium and that at higher concentrations, it increased the contractile force in the cardiac muscle, probably mediated through the release of histamine.

Animals↗
PubMed1991

Isolation of two toxic heptapeptide microcystins from an axenic strain of Microcystis aeruginosa, K-139.

Two toxic heptapeptides were isolated from an axenic Microcystis aeruginosa strain, K-139. Using mainly a non-destructive NMR method, we determined the structure of the major toxin to be 7-desmethylmicrocystin LR which lacks an N-methyl group of the dehydroalanine moiety of microcystin LR. The minor toxin was deduced to be 3,7-didesmethylmicrocystin LR. The chromatographic and NMR analyses of 7-desmethylmicrocystin LR were compared with those of 3-desmethylmicrocystin LR.

Amino Acid Sequence↗
PubMed1991

Pirarubicin-induced endothelium-dependent relaxation in rat isolated aorta.

The mechanism of relaxation produced by pirarubicin [(2"R)-4'-O-tetrahydropyranyladriamycin, THP] has been studied in rat isolated aorta. THP (1.5 x 10(-6)-4.5 x 10(-5) M) markedly relaxed contractions induced by noradrenaline (10(-7) M) in the aorta with endothelium, but not in that without endothelium. The relaxation induced by 1.5 x 10(-5) M THP was inhibited by methylene blue (5 x 10(-6) M), hydroquinone (10(-4) M), phenidone (5 x 10(-5) M), haemoglobin (10(-6) M) and p-bromophenacyl bromide (5 x 10(-5) M), but not by indomethacin (2.5 x 10(-5) M). The relaxation induced by THP (1.5 x 10(-7) -4.5 x 10(-5) M) was inhibited by NG-nitro-L-arginine (10(-5) M), but enhanced by superoxide dismutase (10 units mL-1) or by L-arginine (10(-2) M). However, the THP-induced relaxation was not inhibited by various receptor antagonists such as atropine (10(-6) M), cimetidine (10(-5) M), diphenhydramine (3 x 10(-6) M) and [D-Pro4, D-Trp7,9,10]-substance P(4-11) (1.5 x 10(-6) M). In fifteen anthracycline analogues, THP and 13-dihydropirarubicin (both with a tetrahydropyranyl group) produced endothelium-dependent relaxations. These results suggest that the THP-induced relaxation which is probably mediated by endothelium-derived relaxing factor (EDRF) was not produced by an activation of muscarine, histamine H1 or H2, or substance P receptor, and further that the tetrahydropyranyl group must play an important role in the THP-induced relaxation.

Animals↗
PubMed1991

Neutralization of microcystin shock in mice by tumor necrosis factor alpha antiserum.

Microcystis aeruginosa is a common cyanobacterium in water blooms that appear widely in nutrient-rich, fresh, and brackish waters, and its toxic blooms cause the death of domestic animals. The administration of a crude toxic cell extract of M. aeruginosa K-139 to mice can produce tumor necrosis factor (TNF) and prompt severe physiological disturbances, especially liver damage, which can lead to death. The in vitro production of TNF-alpha by peritoneal macrophages was observed after stimulation with the cell extract or the purified toxin from K-139 cells. The expression of a TNF-alpha mRNA was also detected in spleen cells and peritoneal macrophages after stimulation with the cell extract. However, a previous injection of rabbit anti-murine TNF-alpha serum could prevent the liver damage to some extent and protect the mice from death. These findings indicate the involvement of TNF in microcystin shock.

Animals↗
PubMed1991

Toxicity and toxins of natural blooms and isolated strains of Microcystis spp. (Cyanobacteria) and improved procedure for purification of cultures.

All samples of cyanobacterial blooms collected from 1986 to 1989 from Lake Kasumigaura, Ibaraki Prefecture, Japan, were hepatotoxic. The 50% lethal doses (LD50s) of the blooms to mice ranged from 76 to 556 mg/kg of body weight. Sixty-eight Microcystis cell clones (67 Microcystis aeruginosa and 1 M. viridis) were isolated from the blooms. Twenty-three strains (including the M. viridis strain) were toxic. However, the ratio of toxic to nontoxic strains among the blooms varied (6 to 86%). Microcystins were examined in six toxic strains. Five toxic strains produced microcystin-RR, -YR, and -LR, with RR being the dominant toxin in these strains. Another strain produced 7-desmethylmicrocystin-LR and an unknown microcystin. This strain showed the highest toxicity. Establishment of axenic strains from the Microcystis cells exhibiting extracellularly mucilaginous materials was successful by using a combination of the agar plate technique and two-step centrifugation.

Animals↗
PubMed1991

Site-specific integration of the actinophage R4 genome into the chromosome of Streptomyces parvulus upon lysogenization.

The lysogenization of Streptomyces parvulus by actinophage R4 occurs by site-specific integration of the phage genome into the chromosome. The DNA fragments containing the attachment sites on the host chromosome, the phage genome, and the two junctions created by insertion of the phage genome were cloned and sequenced. The attachment sites were found to share a common core of 12 bp. This common core sequence was not detected in chromosomal DNAs of S. coelicolor and S. lividans.

Bacteriophages↗
PubMed1991

Clinical experience and successful impregnation using an artificial spermatocele.

We have to date installed artificial spermatoceles made of silicone in a total of 33 patients. Artificial insemination of husband (AIH) was performed in 1-9 times using semen collected from 11 of the 33 patients in whom spermatocele was installed, and pregnancy was achieved in 2 cases. Reported cases of pregnancy achieved using semen collected from artificial spermatoceles are few in number; indeed, our successful cases were the fifth and sixth reported so far. The key point for success in achieving pregnancy by means of the artificial spermatocele is considered to be attempting AIH as soon as possible after collecting the sperm, because collection of sperm soon becomes impossible, due to early obstruction of the incised region at the epididymis by degeneration of fibrous tissue. 3% HSA-TMPA medium was found to be useful for sperm collection.

Adult↗
PubMed1991

Combined cisplatin and radiation therapy for advanced bladder cancer.

Since September 1985, 44 patients with advanced urinary bladder cancer have been treated by combined cisplatin and full-dose radiotherapy. The patients were 32 males and 12 females, and their ages ranged from 33 to 83 years, with a median of 67.4 years. Radiotherapy consisting of a tumor dose of 50-60 Gy was administered with cobalt-60. Cisplatin was infused 5 days at a daily dose of 20 mg on the 1st and 4th weeks of treatment. Of the 39 evaluable patients 27 (69.2%) achieved a complete response. Toxicity was also evaluated for those 44 patients. Mainly gastrointestinal toxicity was noted: loss of appetite in 28 (64%), nausea and/or vomiting in 21 (48%), and diarrhea in 8 (18%). Leukocytopenia was noted in 16 (33%) and mild thrombocytopenia in 5 (11%). Mild dermatitis was noted in 8 (18%).

Aged↗
PubMed1991

Experimental transplantation models of mouse sarcoma 180 in ICR mice for evaluation of anti-tumor drugs.

Two new experimental models of transplantable mouse sarcoma 180 were developed in ICR mice in order to examine the optimum transplantation sites and methods. The cervicodorsal hypoderm was evaluated as the best transplantation site for mouse sarcoma 180 among seemingly usable transplantation sites such as groin, armpit, cervicodorsal, abdominal and lumbodorsal hypoderms by hypodermic transplantation. In addition, the lung transplantation model was established by monitoring the survival period as a reliable parameter for evaluation of anti-tumor effects.

Aclarubicin↗
PubMed1991

Constrictor response of small pulmonary arteries to acute pulmonary hypertension during left atrial pressure elevation.

Acute elevations in left atrial pressure (LAP) were induced by altering the volume of air within a balloon inserted into the left atrium; the changes in internal diameter (ID) of small muscular pulmonary arteries (100-600 microns ID) in response to the associated rises of pulmonary arterial pressure (PAP) were measured using an X-ray TV system on the in vivo cat lung. When LAP was elevated to 14 +/- 1, 24 +/- 1, and 30 +/- 1 mmHg, PAP was increased to 21 +/- 1, 30 +/- 1, and 37 +/- 1 mmHg, respectively. With PAP ranging from 16 (control value) to 21 mmHg the ID did not dilate significantly. With PAP of 30-37 mmHg significant ID dilation occurred. The magnitude of the ID dilation (16%) with PAP of 37 mmHg, however, was significantly smaller than that (20%) with PAP of 30 mmHg despite the greater pressure rise. When the elevated PAP of 30-37 mmHg was quickly returned to the control level by rapid balloon deflation, the ID constricted significantly below the control level. The magnitude of the ID constriction was proportional to the degree of the preceding PAP rise and was maximal in the arteries of 200-400 microns ID. A papaverine hydrochloride injection combined with the balloon deflation completely abolished the ID constriction. A phentolamine injection, on the other hand, significantly attenuated the constriction with approximately half of the constriction persisting. The results indicate that an increase in vascular smooth muscle tone occurred in the small muscular pulmonary arteries, particularly those of 200-400 microns ID, in response to the acute rise of PAP above 30 mmHg during the LAP elevation. In addition, the data suggest the partial participation of catecholamines in the active contraction of vascular smooth muscle. The arterial contraction may serve to protect the pulmonary capillaries from an excessive hydrostatic pressure and pulmonary edema.

Angiography↗
PubMed1991

[Ewing's sarcoma in the retroperitoneum].

The patient was a female aged 18. Hematuria was discovered at an examination two years previously at which time the patient was complaining of right lumbar pain. The patient visited our hospital with a chief complaint of right abdominal tumor in June, 1988. A retroperitoneal tumor, 77 X 45 mm in size, was observed by CT and ultrasonic examination, and the right kidney was in hydronephrosis. An operation was performed in September, 1988, based on a diagnosis of retroperitoneal tumor and hydronephrosis. The tumor was seen to have involved the right ureter. Subsequently the tumor was surgically removed; right total nephroureterectomy and partial cystectomy were performed at that time. The removed tumor was 90 X 70 mm in size and 120 g in weight; it was histopathologically diagnosed as extraskeletal Ewing sarcoma. A systemic examination was carried out postoperatively, but no abnormalities were observed. As of September, 1990, the patient had had no recurrence and was being kept observation on an outpatient basis. There have been a total of 210 case reports regarding extraskeletal Ewing sarcoma published worldwide, including our case and 26 cases in Japan, so far as we know. However those of a lesion of retroperitoneal origin are extremely rare, numbering only 11 cases worldwide and 2 Japan. Herein we report our case of extraskeletal Ewing sarcoma with reference to the other 209 cases reported in the literature to date.

Adolescent↗
PubMed1991

Autoantibody specific for transfer ribonucleic acid (tRNA) in patients with autoimmune chronic active hepatitis and primary biliary cirrhosis.

Autoantibody reactive with tRNA was identified by immunoprecipitation of Hela cell extract. Four out of 56 sera from patients with autoimmune chronic active hepatitis (CAH), and four out of 35 sera from patients with primary biliary cirrhosis (PBC) contained antibody directed against gel-purified tRNA in Hela cell extract, but no sera obtained from CAH type B, CAH non-A, non-B, or healthy volunteers did. Further studies on these eight anti-tRNA sera disclosed that 6 of the 8 sera that immunoprecipitated tRNA from Hela cell extract, reacted with purified tRNA, but reacted with neither 5sRNA nor ribosomal RNA species. After proteinase and deoxyribonuclease digestion of Hela cell extract, the epitope for these 6 sera was conserved, and the antigen was sensitive to ribonuclease (anti-tRNA serum). Purified Hela cell DNA digested with Eco RI or Hind III (denatured or non-denatured) could not be immunoprecipitated by these sera. In a patient with autoimmune CAH, the anti-tRNA antibody was weakly positive at week 2 and disappeared 2 months after steroid therapy started, "in parallel" with disappearance of anti-nuclear antibody. In the other 2 sera, the antigen was sensitive to proteinase.

Autoantibodies↗
PubMed1991

[Influence of various factors on glucocorticoid receptors of bronchoalveolar lavage (BAL) cells from rabbits].

It is supposed that the effects of glucocorticoid on target cells are mediated by glucocorticoid receptors. Recent investigations have demonstrated that changes in the composition and function of immune cells in bronchoalveolar lavage (BAL) cells of patients with immunological lung diseases are associated with the intensity of alveolar septal inflammation, or indicate steroid responsiveness. In order to clarify the physiologic changes of glucocorticoid receptor (GR) we measured the GR content of BAL cells obtained from rabbits with various conditions of the host (aging, immunological activation, malnutrition and pretreatment with prednisolone). The specific binding to GR was carried out by incubating BAL cells with 1, 2, 4, 10, 20, 40 nM 3H-prednisolone in the presence or absence of 1.0 x 10(-6) M unlabeled prednisolone. BAL cells from rabbits of various ages exhibited age-dependent reduction of GR content. There were striking differences of GR content in BAL cells from normal and BCG-vaccinated rabbits. The former yielded 3124 +/- 365 binding sites per cell, whereas activated BAL cells showed considerably higher values (6807 +/- 766). Chronological changes in GR content in BAL cells were also observed in normal rabbits pretreated with intravenous injection of prednisolone (2 mg/kg). The GR content was lowest at 3 hours after administration, reaching a peak at two days and then returned to control level. As for nutritional modulation, GR content tended to increase in the initial phase of fasting (days 4 to 8), and then decreased after day 12. In contrast, there were no significant changes in dissociation constants among BAL cells from animals in normal, immunologically activated and malnourished conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗