Search PubMed⌕ Search

Biomedical subjects

S Kitano

Publications and source records attributed to S Kitano.

At least 271 records · Page 15Linked to original sources
PubMed1992

The effects of intraluminal and extraluminal drug application on secretion and smooth muscle tone in the ferret liquid-filled trachea in vitro.

With the ferret liquid-filled trachea in vitro, intraluminal methacholine (MCh), phenylephrine (PE) and histamine (Hist) increased smooth muscle tone and salbutamol (Salb) decreased tone. Lysozyme output was increased by intraluminal MCh and PE. Albumin transport into the lumen was not altered by intraluminal Hist, Salb or PE. The concentration-response curves for smooth muscle contraction and for lysozyme output to extraluminal MCh lay to the left of those for intraluminal MCh. Indomethacin shifted the smooth-muscle response curves to MCh significantly to the left but did not significantly alter lysozyme output. Extraluminal MCh produced a concentration-dependent increase in albumin output whilst intraluminal MCh did so in one of three studies. Albumin output in response to MCh was not significantly altered by indomethacin. Thus, MCh has a less potent effect on smooth muscle and lysozyme secretion and, to a lesser extent, on epithelial albumin transport when given intraluminally. This may be because the epithelium restricts diffusion of the drug or due to the production of a non-prostanoid factor which inhibits smooth muscle responsiveness. Smooth muscle responsiveness is enhanced by blocking cyclooxygenase activity, suggesting MCh-induced release of a prostanoid with relaxant activity.

Animals↗
PubMed1992

Effect of interleukin-1 beta on gene expressions and functions of fibroblastic cells derived from human periodontal ligament.

The present study shows the effect of interleukin-1 beta (IL-1 beta) on some gene expressions and functions of fibroblastic cells (HPLF) derived from human periodontal ligament. HPLF were used at passages number 5 to 10. IL-1 beta increased DNA synthesis in both a dose- and an incubation time-dependent manner. IL-1 beta in combination with tumor-necrosis factor alpha or transforming growth factor beta synergistically stimulated the DNA synthesis in the cells. Since many studies have shown that the c-myc oncogene is involved in cell proliferation and differentiation, the effect of IL-1 beta on c-myc messenger RNA (mRNA) level in HPLF was examined. IL-1 beta induced a marked c-myc mRNA level in the cells at 90 minutes after initiation of the cytokine treatment. On the other hand, IL-1 beta significantly inhibited alkaline phosphatase (ALP) activity of the cells in a dose-dependent manner. Also an inhibitory effect was observed on the liver/bone/kidney ALP mRNA level of the cells, and this inhibition by IL-1 beta was dose- and incubation time-dependent. These results suggest that IL-1 beta is a regulatory cytokine involved in the regeneration of the human periodontal ligament.

Alkaline Phosphatase↗
PubMed1992

Porphyromonas gingivalis fimbriae induce expression of the neutrophil chemotactic factor KC gene of mouse peritoneal macrophages: role of protein kinase C.

To account for infiltration of the periodontal tissues by neutrophils, the present study was undertaken to examine whether Porphyromonas gingivalis fimbriae, important structures involved in attachment of the bacteria to periodontal tissues, induce gene expression of the neutrophil chemoattractant KC in macrophages. The fimbriae induced expression of the KC gene of mouse peritoneal macrophages in a dose-dependent fashion. The peak of KC gene expression was observed as early as 1 h after initiation of the treatment. However, the gene expression was short lived, with the expression decreasing gradually after 6 h. A nuclear transcriptional assay showed that the fimbriae regulated the KC gene expression at a posttranscriptional level. We observed that the fimbria-induced KC gene expression was not regulated by endogenous or exogenous prostaglandin. Furthermore, forskolin, a potent activator of adenyl cyclase, and dibutyryl cyclic AMP were incapable of inducing KC gene expression of the peritoneal macrophages. H-8 and HA 1004, inhibitors of cyclic nucleotide-dependent protein kinases, had little effect on the fimbria-induced KC gene expression. On the other hand, the fimbria-induced KC gene expression was inhibited markedly by treatment with H-7, a potent inhibitor of protein kinase C. We also observed that phorbol 12-myristate 13-acetate, a specific activator of protein kinase C, induced KC gene expression of peritoneal macrophages in a dose-dependent fashion. In addition, the fimbria-induced KC gene expression was suppressed in the peritoneal macrophages pretreated for 24 h with phorbol 12-myristate 13-acetate. These results suggest that the KC gene expression was mediated through activation of protein kinase C and not through that of cyclic nucleotide-dependent protein kinases. The present study indicates that P. gingivalis fimbriae can induce gene expression of the neutrophil chemotactic factor KC by macrophages via protein kinase C and suggests that this factor may be involved in infiltration of neutrophils into the periodontal tissues of adult periodontal patients.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1992

Circulating suppressing factor for the muscarinic acetylcholine receptor in patients with senile dementia of the Alzheimer type.

Circulating suppressing factor for the binding of quinuclidinyl benzilate (QNB), an antagonist for the muscarinic acetylcholine receptor, to the synaptic membranes was evaluated in 48 patients with senile dementia of the Alzheimer type (SDAT), in 17 patients with the vascular type dementia (VTD) and in 11 nondemented elderly subjects (NE). The mean suppression rate on the binding in the SDAT group was significantly greater than that in the NE group, although that in the VTD group was similar to that in the NE group. Moreover, the percent QNB binding was significantly (p < 0.05) correlated with the score of the mini-mental state in the SDAT group. The circulating suppressing factor may participate in the pathogenesis of SDAT.

Aged↗
PubMed1992

[A case of late-onset Pick's disease with polyuria].

A 72-year-old male was admitted to our hospital with a 2-year history of polyuria, prosopagnosia and aphasia. He showed characteristic clinical features of Pick's disease such as stereotyped verbal output and behavior and personality changes. CT and MRI scans showed marked atrophy in the bilateral anterior temporal lobes mild atrophy of the bilateral frontal lobes. SPECT scans revealed perfusion abnormalities in corresponding areas. A 6-hour-water deprivation test resulted in decrease in the urine volume and in concentration of the urine, suggesting abnormality of his secondary drinking behavior. Polyposia resulting in polyuria as a clinical manifestation may be due to stereotypic behavior which is often seen in Pick's disease.

Aged↗
PubMed1992

Effects of manidipine hydrochloride on proliferation and glycosaminoglycan synthesis of cultured vascular smooth muscle cells.

The effects of manidipine hydrochloride, a calcium channel blocker, on the proliferation and the synthesis of glycosaminoglycans (GAG) in cultured rat aortic vascular smooth muscle cells (VSMC) were studied. Mandipine hydrochloride suppressed the DNA synthesis of VSMC dose dependently at concentrations of more than 10(-8) M. Mandipine hydrochloride 10(-6) M suppressed proliferation of VSMC to 50% of the control value. Manidipine hydrochloride stimulated the synthesis of GAG at concentrations above 10(-11) M. Manidipine hydrochloride 10(-8) M stimulated synthesis of GAG to 450% of control. Our findings suggest that because mandipine hydrochloride suppresses proliferation and stimulates GAG synthesis of VSMC, it may be an anti-arteriosclerotic agent.

Animals↗
PubMed1992

[An experimental model of intravitreal neovascularization in rabbits].

The author developed a consistent model of intravitreal neovascularization in the eyes of pigmented rabbits by incomplete posterior vitreous detachment after air injection followed by implantation of basic fibroblast growth factor (b-FGF; 250 ng or 1 microgram) in the vitreous and simultaneous intravitreal injection of DL-alpha-aminoadipic acid in physical saline solution (1 mg/kg). Newly formed vessels were observed in the proliferative fibrous membrane that surrounded the b-FGF pellet. In fluorescein angiography, we observed fluorescein leakage from the newly formed vessels. Histologically, the newly formed vessels showed fenestration of endothelial cells. This method provides an easy and consistent model to study neovascularization.

2-Aminoadipic Acid↗
PubMed1992

EDTA induces differentiation and suppresses proliferation of promyelocytic leukemia cell line HL-60--possible participation of zinc.

Effects of ethylenediaminetetraacetic acid (EDTA), a chelator of divalent cations, on the proliferation and differentiation of human promyelocytic leukemia cell line HL-60 were examined. Incubation of HL-60 cells with 200 microM of EDTA suppressed cell proliferation, and induced differentiation assessed by reductivity of nitro blue tetrazolium and activity of alpha-naphthyl butyrate esterase. These effects were inhibited by zinc (Zn) dose-dependently at concentrations of up to 20 microM, but not by other divalent cations including Ca, Mg, Fe, Cu, Ni, or Cd. Although addition of 200 microM EDTA for 24 hr decreased the c-myc mRNA level of HL-60 cells, coaddition of 20 microM of Zn also reversed this effect on c-myc mRNA level. Treatment with EDTA did not change the half-life time of degradation of c-myc mRNA after addition of actinomycin D (5 micrograms/ml). These findings suggest that Zn deficiency suppresses c-myc gene transcription which is followed by suppression of proliferation and induction of differentiation of HL-60 cells.

Blotting, Northern↗
PubMed1992

[Surgical versus non-surgical treatment in patients with esophageal varices--a prospective randomized study].

In Japan, non-shunting procedures and selective shunt such as esophageal transection (ET), and distal splenorenal shunt (DSRS) have been widely performed. A prospective randomized trial was done to assess the effects of EIS and DSRS for treating patients with esophageal varices. Ninety-six Japanese with good liver function (Child A or B) and large esophageal varices were randomly assigned to one of three groups given different treatments; (EIS, n = 32), (ET, n = 32) and (DSRS, n = 32). Five patients (15.6%) of the DSRS group has to be excluded from this study, because of severe chronic pancreatitis. No patient died within 30 days of the treatments. The 5-year cumulative bleeding rates were 0%, 4.3% and 12.1% in the EIS, ET and DSRS groups, respectively, with no statistical significances. In no case in the three groups did the death occur because of variceal bleeding. Nineteen patients died mainly due to the underlying liver disease; 5 in the EIS, 5 in the ET and 9 in the DSRS group. There was no statistically significant difference in the survival rates among the three groups. We conclude that EIS is a satisfactory alternative to ET or DSRS for the management of patients with large esophageal varices.

Adult↗
PubMed1992

Splenic hyperkinetic state and splenic artery aneurysm in portal hypertension.

Forty-eight out of six hundred and thirty patients with portal hypertension undergoing a celiac angiography series were diagnosed as cases of splenic artery aneurysm during the period 1977-1988. The case-control study of patients with portal hypertension with splenic artery aneurysms and those without was designed to characterize the angiological features. The splenic arterial flow was assessed by measuring the radii of the splenic arteries on celiac arteriograms. In the portal hypertensive patients with splenic artery aneurysms, the splenic artery was larger (p < 0.05) and the splenic arterial flow greater (p < 0.05), and these patients were in a more hyperkinetic state, than were those with no splenic artery aneurysm. The study suggests that splenic artery aneurysms in cases of portal hypertension may be the consequence of a hyperkinetic state in the spleen.

Adolescent↗
PubMed1992

Comparative effects of 5% ethanolamine oleate versus 5% ethanolamine oleate plus 1% polidocanol for sclerosing esophageal varices.

Sixty-six patients with portal hypertension and esophageal varices due to liver cirrhosis were randomized to receive either 5% ethanolamine oleate (EO) or 5% EO plus 1% polidocanol (EOP) as a sclerosant for endoscopic injection sclerotherapy (EIS). The two groups were well matched with regard to age, sex and the severity of liver disease. In no patient in the two groups was there any major complication, such as esophageal perforation or esophageal bleeding. Eradication of esophageal varices was attained with an average of 4.7 and 4.3 sessions of endoscopic injection sclerotherapy in the ethanolamine oleate and polidocanol groups, respectively. Data on one patient in the ethanolamine oleate group had to be excluded because he left the hospital after 2 sessions of endoscopic injection sclerotherapy. Esophageal ulcers occurred earlier in the polidocanol group (after an average of 2.8 weeks) than in the ethanolamine oleate group (3.8 weeks), the difference being statistically significant (P < 0.01). The rate of occurrence of esophageal stricture requiring more than 2 sessions of bougienage was significantly (P < 0.01) higher in the polidocanol group (16/33, 48%) than in the ethanolamine oleate group (4/32, 12%). This study suggests that the two sclerosants have equal efficacy for treating patients with esophageal varices. With polidocanol there was ulceration and stricture in the distal esophagus.

Drug Combinations↗
PubMed1992

[The local immune system of ocular surface].

Local immunity on the ocular surface was observed in guinea pigs immunized with horseradish peroxidase (HRP) by determining the activity of a specific antibody in local sites of the conjunctiva by the enzyme-antigen method, which enables a specific antibody to be stained. In addition, immunohistochemical study of the localization of IgA was performed by the enzyme-labelled antibody method. The enzyme-antigen method revealed a number of positive cells in the subconjunctival tissue and the parafollicular area of conjunctival-associated lymphoid tissue. These cells were identified as plasma cells by electron microscopy. The mirror section technique revealed that the cells positive for the enzyme-antigen method were consistent with anti-IgA-positive cells at many sites. Thus the distribution of plasma cells secreting IgA-specific antibody responsible for local immunity on the ocular surface was observed immunohistochemically. The results suggest that immunocytes in the conjunctival-associated lymphoid tissue differentiate and mature into specific antibody-producing plasma cells.

Animals↗
PubMed1992

[Immunoresponses to the external antigen in conjunctival-associated lymphoid tissue].

The local immunity of the ocular surface is governed by conjunctival-associated lymphoid tissue (CALT), secretory IgA and immunocytes. The authors performed a histological investigation of the time-course changes in CALT caused by invasion of antigen to the ocular surface through the instillation of horseradish peroxidase (HRP) into the guinea pig eye. We used PAS staining, peroxidase staining, alkaline phosphatase staining. The lymphoepithelial cells of CALT phagocytized HRP 30-60 min after the instillation, and formed intraepithelial pockets 24 hours after instillation. The follicular area of CALT was strongly positive for alkaline phosphatase 2 weeks after instillation. These changes were considered to be the first step in the manifestation of local immunity on the ocular surface. Each staining technique revealed differences between the lymphoepithelium and conjunctival epithelium, suggesting that lymphoepithelium has characteristics different from those of conjunctival epithelium.

Animals↗
PubMed1991

Transforming growth factor-beta-induced gene expression of monocyte chemoattractant JE in mouse osteoblastic cells, MC3T3-E1.

A recent study demonstrated that PDGF-inducible JE is an inflammatory cytokine that directs chemotactic activity of monocytes. Accumulation of monocyte/macrophage lineage cells at site of bone tissue sites is very important for formation of multinucleate osteoclasts, which mediate bone resorption. Since transforming growth factor-beta (TGF-beta) is a potent regulator in bone remodeling, we examined whether TGF-beta induced JE gene expression in mouse osteoblastic cells, MC3T3-E1. TGF-beta induced a maximum JE mRNA expression at 3 hr after initiation of the cytokine treatment. This maximal expression was observed in when TGF-beta was used at a concentration of 1 ng/ml. The chemotactic activity for human monocytes was detected in conditioned medium of TGF-beta-treated cells, and the chemotactic activity was neutralized by anti-JE serum treatment.

Animals↗
PubMed1991

High rate of portal thrombosis after splenectomy in patients with esophageal varices and idiopathic portal hypertension.

Data on 126 consecutive patients who were admitted to our clinics from January 1979 to May 1989 were scrutinized to assess changes in portal hemodynamics following splenectomy. Two groups were classified: (1) a group of 106 patients with cirrhosis of the liver and (2) a group of 20 patients with idiopathic portal hypertension (IPH). Portal thrombosis was present in five (25.0%) of the 20 patients with IPH and in two (1.8%) of the 106 patients with cirrhosis of the liver. As seen on celiac arteriography, the mean (+/- SD) diameter of the trunk of the splenic artery and vein was 8.99 +/- 1.55 and 16.2 +/- 3.6 mm, respectively, in patients with IPH, while it was 7.94 +/- 1.28 and 14.2 +/- 3.1 mm, respectively, in patients with cirrhosis of the liver. Changes in portal venous pressure were 78.4 +/- 59.4 mm H2O in patients with IPH and 43.5 +/- 38.7 mm H2O in patients with cirrhosis of the liver. There were no significant differences in the maximum level of thrombocytes in patients with IPH or in those patients with cirrhosis of the liver. These events suggest that portal thrombosis can occur with a significantly higher incidence in patients with IPH than in those patients with cirrhosis of the liver after splenectomy, and a decrease in blood flow in the portal vein may be closely linked to the formation of portal thrombosis after splenectomy in patients with IPH. Preoperative examination of portal hemodynamics must be thorough.

Esophageal and Gastric Varices↗
PubMed1991

Clinical management of gastric cancer and concomitant esophagogastric varices.

We report the late results of treatment of 13 consecutive patients with gastric cancer and concomitant esophagogastric varices. Of seven good-risk patients classified as Child's class A or B, gastrectomy together with selective shunt operation was performed in two, total gastrectomy with splenectomy in three, and distal partial gastrectomy with paraesophageal devascularization without splenectomy in one. The remaining patient with early gastric cancer underwent distal partial gastrectomy following repeated endoscopic injection sclerotherapy (EIS) for treatment of the esophageal varices. Although the majority of patients who underwent surgical repair of varices (i.e., shunt, splenectomy, or devascularization) died, total gastrectomy with splenectomy was the only procedure that led to control of the esophageal varices. Since partial gastrectomy combined with EIS limits the morbidity and mortality of an extensive resection and at the same time controls esophageal variceal bleeding, it is probably the procedure of choice for patients with a carcinoma in the lower two-thirds of the stomach. Concerning non-surgical cases, two patients were effectively treated using laser endoscopy and EIS, without the occurrence of variceal bleeding. The remaining four patients, given chemotherapy or irradiation for treatment of gastric carcinoma, died within 4 months with variceal bleeding or liver failure. For the poor-risk patients with evidence of severe liver dysfunction, laser treatment and EIS would be the treatment of choice.

Aged↗