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S Shiraishi

Publications and source records attributed to S Shiraishi.

At least 19 recordsLinked to original sources
PubMed1999

Combined catheter embolization and femorofemoral bypass for pseudoaneurysm of the right external iliac artery: report of a case.

Performing direct surgery for postoperative hemorrhage caused by intraperitoneal arterial injury is very difficult. We report herein the case of a 52-year-old woman who developed sudden right lower abdominal pain after numerous laparotomies and radiotherapy for advanced uterine cancer. A diagnosis of pseudoaneurysm of the right external iliac artery was made, and an emergency catheter embolization and femorofemoral bypass was successfully performed under local anesthesia. The patient was able to walk the next day. To the best of our knowledge, this is the first report of such a combined procedure in the literature.

Adenocarcinoma↗
PubMed1999

Immunohistochemical expression of vascular endothelial growth factor/vascular permeability factor in atherosclerotic intimas of human coronary arteries.

Neovascularization is well known to occur in human atherosclerotic plaques; however, its pathophysiological roles, mechanisms, and stimuli in atherogenesis still remain unclear. In this study, 525 tissue blocks of coronary artery tissue obtained at autopsy from 48 patients ranging in age from 20 to 93 years old (mean+/-SD, 71+/-15 years) were immunohistochemically examined for vascular endothelial growth factor (VEGF) expression in the atherosclerotic intimas. The atherosclerotic lesions were histopathologically classified into types I through VI, as proposed by the American Heart Association Committee, and the numbers of intimal blood vessels and VEGF-positive cells were then morphometrically counted in sections that were immunohistochemically examined with anti-CD34 and human VEGF antibodies, respectively. The more the atherosclerotic lesion type advanced, the more often the lesion contained intimal blood vessels, which were expressed as percentages of the intimal section with intimal microvessels, viz, diffuse intimal thickening (DIT): 0% (0/111); type I, 31% (32/104); II, 42% (10/24); III, 66% (77/117); IV, 72% (48/67); V, 79% (70/89); and VI, 100% (13/13), P<0.0001. The number of VEGF-positive cells per intimal section was also positively correlated with the number of intimal blood vessels (P<0. 0001). The VEGF-positive cells were scattered in the fibrous caps as well as the shoulders and deeper areas of the plaques, and the double-immunostaining method revealed that the VEGF-positive cells were largely spindle-shaped, smooth muscle cells with some macrophage-derived foam cells. These findings thus suggest the possibility that the VEGF expressed by the smooth muscle cells and foamy macrophages in the atherosclerotic intimas can act as a local and endogenous regulator of endothelial cell functions, including intimal neovascularization, in atherosclerotic lesions of human coronary arteries.

Adult↗
PubMed1998

Selective inhibition by riluzole of voltage-dependent sodium channels and catecholamine secretion in adrenal chromaffin cells.

We examined the effects of riluzole, a neuroprotective drug, on voltage-dependent Na channels, nicotinic receptors, and voltage-dependent Ca channels, as well as catecholamine secretion, in comparison with those of verapamil and nicardipine, in primary cultures of bovine adrenal chromaffin cells. Riluzole inhibited veratridine-induced 22Na influx via voltage-dependent Na channels even in the presence of ouabain, an inhibitor of Na,K-ATPase. Blockade of Na channels by riluzole was concentration-dependent with an IC50 of 5.3 microM. It was associated with a similar concentration-related reduction of veratridine-induced 45Ca influx via voltage-dependent Ca channels, and of catecholamine secretion. Riluzole had no effect on 45Ca influx caused by high K, which directly activates voltage-dependent Ca channels, and on nicotine-induced 22Na influx, which passes through the nicotinic receptors. Verapamil and nicardipine attenuated 22Na influx caused by veratridine or nicotine at the same concentrations as they suppressed high K-induced 45Ca influx. The inhibitory effect of riluzole on veratridine-induced 22Na influx disappeared at high concentrations of veratridine. A potentiation of veratridine (site 2 toxin)-induced 22Na influx caused by alpha-scorpion venom (site 3 toxin), beta-scorpion venom (site 4 toxin), or brevetoxin PbTx-3 (site 5 toxin), occurred in the presence of riluzole in the same manner as in control cells. These results suggest that riluzole binds to the veratridine site in voltage-dependent Na channels. It does not impair the cooperative interaction between the functional peptide segments of Na channels, but selectively inhibits gating of Na channels, thereby reducing Ca influx via Ca channels and catecholamine secretion. In contrast, verapamil and nicardipine suppress Na influx both Na channels and nicotinic receptors.

Animals↗
PubMed1998

Morphometric analysis of the immunohistochemical expression of Clara cell 10-kDa protein and surfactant apoproteins A and B in the developing bronchi and bronchioles of human fetuses and neonates.

Morphometric analyses of the immunohistochemical expression of the Clara cell secretory 10-kDa protein (CC10) and surfactant apoproteins A and B (SP-A and -B) were carried out on the developing bronchi and bronchioles of human fetuses and neonates. We analysed the ratio of the number of CC10-positive cells per subepithelial length of the bronchial or bronchiolar basement membrane and found that both the bronchial and the bronchiolar population of CC10-positive cells was significantly higher than that of either SP-A or SP-B. In addition, CC10 was found to be distributed mainly in the bronchiole. CC10-positive cells began to be recognized in the late pseudoglandular phase (15 weeks of gestation) and thereafter gradually increased in the canalicular and terminal sac phases, which correspond to the active development period of the acini or peripheral airways. The earliest expression of SP-A was also noted at 15 weeks of gestation, but its positive epithelial cells were present mainly in the larger bronchi. Double immunohistochemical staining for CC10 and SP-A revealed that the CC10-positive cells lining both the bronchi and bronchioles were different from the SP-A-positive cells. This finding suggests that CC10-positive cells are functionally and developmentally heterogeneous in both fetal and neonatal lungs in humans.

Animals↗
PubMed1998

Unruptured aneurysm of the sinus of Valsalva into the pulmonary artery.

Congenital aneurysms of the sinus of Valsalva are rare lesions. Because the aortic root is central, the aneurysm can rupture into any cardiac chamber, and virtually all combinations of sinus and chamber fistulas have been described. Rupture into the pulmonary artery, however, is very rare. We encountered a 14-year-old boy with conal ventricular septal defect and right coronary cusp prolapse with an unruptured aneurysm of the sinus of Valsalva into the pulmonary artery.

Adolescent↗
PubMed1998

Mechanisms underlying the neurogenic relaxation in dog isolated hepatic arteries.

In canine hepatic arterial strips responding to nicotine with contraction, prazosin abolished the response or reversed it to a relaxation. Mechanisms underlying the relaxation were analyzed in hepatic and coronary arterial strips denuded of the endothelium and treated with prazosin and indomethacin. In the hepatic arterial strips precontracted with prostaglandin (PG) F2alpha, nicotine-induced relaxations were not influenced by atropine but were inhibited by timolol and abolished by hexamethonium. Treatment with [8-37] calcitonin gene-related peptide ([8-37] CGRP), a selective CGRP1-receptor antagonist, also attenuated the nicotine-induced relaxation, but a vasoactive intestinal polypeptide antagonist was without effect. Combined treatment with timolol and [8-37] CGRP depressed the response to a greater extent than either antagonist alone. The slight relaxation remaining under the combined treatment was abolished by NG-nitro-L-arginine (L-NA) and restored by L-arginine. In coronary arterial strips precontracted with PGF2alpha, nicotine produced a moderate relaxation, which was abolished or markedly inhibited by treatment with hexamethonium or timolol but was unaffected by L-NA. It is concluded that the nicotine-induced relaxation is mediated by norepinephrine, CGRP, and NO released from perivascular nerves in dog hepatic arterial strips; the responses associated with activations of beta-adrenoceptors and CGRP1 receptors are predominant over those to NO. The coronary arterial relaxation seems to be mediated by neurogenic norepinephrine but not by NO.

Animals↗
PubMed1998

[A case report of successful mitral valve replacement for infective endocarditis during pregnancy].

Infective endocarditis is an important but uncommon complication in obstetric or gynecologic practice. A 32 weeks' pregnant woman exhibited endocarditis due to Streptococcus oralis. The present case was successfully managed by means of aggressive antibiotic and diuretic treatments appropriate for endocarditis. The patient entered spontaneous labor at the estimated date of confinement and delivered of healthy 2.8 kg boy. After four weeks later scheduled mitral valve replacement with SJM valve was performed at the chronic stage of endocarditis. Her postoperative recovery was uneventful and she was discharged 40 days after the operation.

Adult↗
PubMed1997

Disturbed circadian core body temperature rhythm and sleep disturbance in school refusal children and adolescents.

We examined the circadian rhythm of core body temperature (CBT) in 22 school refusal patients, ages between 12 and 18 years, who did not have any physical or psychiatric disorders, but had indefinite complaints, and were suspected to have a circadian rhythm disturbance. To obtain normal data for analysis, CBT in 9 healthy age-matched school attendants who did not have any sleep, psychiatric, or medical disturbance were monitored. Circadian variation of CBT in school refusal patients did not present a clear rhythm, and appearance time of their lowest CBT was markedly delayed compared to healthy subjects. Amplitude of circadian CBT changes, fitted to a cosinor curve by the least square method, was significantly smaller in school refusals than in healthy subjects. These findings suggest that in school refusal patients who do not have physical and psychiatric disorders, clinical psychosomatic symptoms (e.g., fatigue and memory disturbance) and school refusal could be closely related to the desynchronization of their biorhythms, particularly the circadian rhythm of body temperature and sleep-wake rhythm.

Adolescent↗
PubMed1997

Alteration of pharmacokinetics and nephrotoxicity of cisplatin by alginates.

This study was undertaken to demonstrate that alginates could form a complex with cisplatin and that the pharmacokinetics and nephrotoxicity of cisplatin could be altered by this complexation. The complexes were prepared with alginates of mean molecular weights of 10000 (AL-1) and 40000 (AL-2). The plasma clearances of cisplatin-alginate complexes were significantly reduced when compared with the drug alone. Urinary excretion of platinum (Pt) was increased when animals were dosed with the cisplatin-AL-1 complex, but not with the cisplatin-AL-2 complex. Renal clearance of cisplatin, when administered alone, was more rapid during the first 2 h than the rest of the study period (96 h) and was higher than its plasma clearance, which is consistent with irreversible binding of cisplatin to plasma protein. On the other hand, renal clearance of cisplatin-alginate complexes was not highly time dependent, and the values were more similar to those of plasma clearance. Complexation of cisplatin with alginates, especially AL-1, inhibited the accumulation of Pt in the kidneys and reduced blood urea nitrogen elevation by cisplatin. The in vitro antitumor activities against U937, P388, and cisplatin-resistant P388 (P388/cisplatin) cells were similar among cisplatin and its alginate complexes. These studies indicated that the pharmacokinetics and nephrotoxicity of cisplatin could be altered through complexation with alginate by (1) reducing cisplatin clearance, (2) inhibition of Pt accumulation of in the kidneys, and (3) reduction of apparent nephrotoxicity without decrease in in vitro antitumor activity.

Alginates↗
PubMed1997

beta1-Adrenoceptor-mediated relaxation by norepinephrine in dog hepatic arteries.

Dog hepatic arterial strips treated with prazosin responded to norepinephrine with concentration-related, endothelium-independent relaxations, the maximal response being 81.7% of the papaverine-induced maximal relaxation that was markedly greater than that in renal arteries. The norepinephrine-induced relaxation in hepatic arteries was significantly attenuated by metoprolol but not influenced by butoxamine. Relaxant responses to norepinephrine of dog hepatic arteries appear to be mediated by the beta1-adrenoceptor subtype, like those of coronary arteries. Evidence for functioning of the beta1-subtype in hepatic arteries would contribute to the analysis of neural and hormonal regulation of blood flow in the liver.

Adrenergic alpha-Antagonists↗
PubMed1996

Membrane knobs of unfixed Plasmodium falciparum infected erythrocytes: new findings as revealed by atomic force microscopy and surface potential spectroscopy.

Cerebral malaria, a severe complication of malaria, is caused by the obstruction of cerebral microvessels by Plasmodium falciparum-infected erythrocytes. Such cells adhere to endothelial cells by means of "knobs" induced on the red cell membrane by the parasites. When atomic force microscopy was used to investigate the structure of the knobs of unfixed infected red cells, each knob was found to consist of two distinct subunits, knob components that have never been seen in chemically fixed knobs examined by conventional transmission electron microscopy. Surface potential spectroscopy revealed that the knobs have a positive charge (+20 mV), whereas the remainder of the red cell plasma membrane is negatively charged. Since endothelial plasma membranes have a negative charge, the charge difference between knobs and endothelium may play a significant role in cytoadherence between the two cell types. The subunit structure of the knobs may be a steric necessity to align adherence molecules so that they can exert their effect. This study shows that the atomic force microscope has great potential for examination of cells in their native state; in combination with surface potential spectroscopy, it may uncover fundamental processes and mechanisms in cell function.

Animals↗
PubMed1996

Undifferentiated carcinoma of the broad ligament in a 28-year-old woman--a case report and results of immunohistochemical and electron-microscopic studies.

A case of undifferentiated carcinoma of the broad ligament is reported. The patient was a 28-year-old Japanese woman who underwent laparotomy for a cystic and solid tumor of the left broad ligament. The tumor measured 9 cm in diameter and was unattached to the uterus, ipsilateral ovary, or salpinx. Histological examination revealed tumor tissue consisting of solid nests of irregular configuration and rather small to medium-sized undifferentiated epithelial cells. The tumor cells were positive for cytokeratin, but negative for CA125, epithelial membrane antigen, S-100 protein, amylase, carcinoembryonic antigen, chromogranin A, synaptophysin, HHF35, desmin, and vimentin. Electron-microscopic examination revealed gap junctions and primitive cellular junctions, but no intracytoplasmic mucous granules or microvilli on the surface of the tumor cells. This is the first report of undifferentiated carcinoma of the broad ligament as far as we have been able to determine from a search of the literature.

Adnexal Diseases↗
PubMed1996

Cuticular plasticization induced by copulatory stimuli in female Haemaphysalis longicornis (Acari:Ixodidae).

Partially engorged adult female ticks, Haemaphysalis longicornis Neumann, received complete, incomplete, or no copulatory stimuli. Subsequently, they were inflated with physiological saline by injection into the haemocoel. Ticks that copulated received both preinseminational and inseminational stimuli and increased their body volume > 10-fold. Ticks that incompletely copulated received only preinseminational stimuli and expanded slightly, whereas ticks that did not copulate did not expand. These results show that the soft integument of H. longicornis only expanded after complete copulation. Therefore, copulatory stimuli induced cuticular plasticization.

Animals↗
PubMed1996

[Isolation of Vibrio cholerae in imported frozen seafood and their cholera-enterotoxin production].

A survey study for Vibrio cholerae in imported seafood was conducted during January 1991 to December 1994. A total of 7,439 specimens (approximately 20% of all imported food) were randomly picked up and examined for contamination of V. cholerae. Among these, V. cholerae O1 were isolated from 9 specimens, but they were all cholerae enterotoxin (CT)-negative. In terms of V. cholerae non-O1, a total of 2,803 specimens (37.4%) were contaminated with this vibrio. Shrimp, especially the ones still in their shells and imported from Asian countries such as India and Indonesia, were highly contaminated with V. cholerae. Although no strains of V. cholerae O1 isolated in this study produced CT, 2 strains of V. cholerae non-O1 were proved to be CT-producers. Taking together the high contamination of V. cholerae in imported seafood and a part of those strains producing CT, we believe that careful survey for the possible contamination of V. choleare in imported seafood is necessary.

Cholera Toxin↗
PubMed1996

Genetic characterization of Epimedium species using random amplified polymorphic DNA (RAPD) and PCR-restriction fragment length polymorphism (RFLP) diagnosis.

Total DNA was extracted from the leaves of seven Epimedium species grown in different places in Japan. Their genetic characterization was performed by DNA analyses of random amplified polymorphic DNA (RAPD) using 32 random primers having 10 base sequences, and by restriction fragment length polymorphism (RFLP). E. sagittatum and E. koreanum were easily distinguished by a representative amplified band pattern. It became evident that E. sagittatum had extremely different genetic composition compared to the other species. A dendrogram obtained from the similarity matrix by cluster analysis indicates that E. sagittatum can be completely isolated from the other species. Moreover, it became evident that E. grandiflorum var. higoense, E. trifoliatobinatum and E. koreanum are independent species, contrary to the previous assumption that they are subspecies or a variety. The geographical variation of E. sempervirens was confirmed by cluster analysis. E. diphyllum showed wide genetic variations, in spite of sampling from the same area.

Base Sequence↗
PubMed1996

[Study of malignant lymphoma in the parotid gland region].

Malignant lymphomas arising in the salivary glands are very uncommon. The vast majority of these lesions are classified as extranodal non-Hodgkin's lymphoma. Clinical presentation, management, histopathology, and outcome in 11 cases of non-Hodgkin's lymphomas of the parotid gland region were reviewed. The ages of the patients ranged from 25 to 80 years (average 56.0 years) and the male to female ratio was 5:6. Presenting symptoms were painless masses (10 cases) and a painful mass (1 case) in the parotid gland region. None of the patients had facial nerve paralysis. It seems to be difficult to diagnose malignant lymphomas of the salivary glands preoperatively, because an open biopsy of the salivary glands is generally contraindicated. We failed to diagnose malignant lymphoma in the parotid gland preoperatively. The clinical stages were stage I in 5 cases, stage II in 5 cases, and stage III in 1 case. There was no patient with stage IV. Three of the stage I tumors were diagnosed as MALT (mucosa-associated lymphoid tissue) lymphomas. Eight of the tumors were treated surgically and an open biopsy of the parotid gland tumor was performed in 1 case and open biopsy of a neck lymph node in 2 cases for the purpose of diagnosis. After the diagnosis, these cases were followed up with or without radiotherapy and chemotherapy. Follow-up ranged from 6 to 109 months. The 5-year-survival rate was 60%. The outcome for this group was found to be as good as that reported by others.

Adult↗