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Biomedical subjects

K Kishi

Publications and source records attributed to K Kishi.

At least 73 records · Page 4Linked to original sources
PubMed2001

Production of hepatocyte growth factor from human lung microvascular endothelial cells induced by interleukin-1beta.

To investigate the possible role of hepatocyte growth factor (HGF) in the reconstruction process following inflammatory damage in lung tissue, we compared HGF production of human lung microvascular endothelial cells (HLWECs) and human umbilical vein endothelial cells (HUVECs) after stimulation by interleukin(IL)-1beta. In an HLMEC-conditioned medium, large amounts of total (single and 2-chain) HGF were detected, and were 26- to 28-fold higher than those in HUVECs or human lung fibroblasts. The production of total HGF increased in a dose-dependent manner (4.7 to 9.2 times) with IL-1beta. In contrast, the amount of HGF in an HUVEC-conditioned medium was unaffected by IL-1beta treatment. The amount of cell-associated HGF also showed a dose-related increase (140% to 160%) in HLMECs, but not in HUVECs with IL1beta. In addition, HGF and c-met (HGF receptor) mRNAs in HLMECs and HUVECs were examined by the RT-PCR method. HGF and c-met mRNAs were clearly detected in HLMECs before and after treatment with IL-1beta, but not in HUVECs. These results suggest that increases in HGF production from HLMECs may play a role in the reconstruction process following inflammatory damage in lung tissue.

Cells, Cultured↗
PubMed2001

Characterization of a membrane-bound arginine-specific serine protease from rat intestinal mucosa.

Previously we isolated and characterized a membrane-bound, arginine-specific serine protease from pig intestinal mucosa [J. Biol. Chem. 269, 32985-32991 (1994)]. For further characterization of this type of enzyme, we cloned a cDNA from rat intestinal mucosa encoding the precursor of a similar protease. The partial amino acid sequences determined for the pig enzyme were found to be shared almost completely by the rat enzyme. The serine protease domain of the rat enzyme, heterologously expressed in Escherichia coli, specifically cleaved Arg (or Lys)-X bonds with a marked preference for Arg-Arg or Arg-Lys, similar to the pig enzyme. The mRNA for the rat enzyme was shown to be distributed mainly in intestine, and the enzyme was detected in the duodenal mucosa as a 70 kDa protein. Immunohistochemical analysis of the small intestinal tissue showed that the enzyme is localized mainly on brushborder membranes.

Amino Acid Sequence↗
PubMed2001

Pretreatment of mice with clindamycin improves survival of endotoxic shock by modulating the release of inflammatory cytokines.

Suppression of endotoxin release and subsequent production of inflammatory cytokines is crucial in the treatment of septic shock. We investigated the effect of clindamycin (CLI) on endotoxic shock induced in mice by Escherichia coli lipopolysaccharide (LPS). Mice were treated with CLI (160 to 600 mg/kg) or saline and then injected with E. coli LPS and D-(+)-galactosamine intraperitoneally 0.5 h after CLI administration. Pretreatment with CLI significantly improved survival in a dose-dependent manner (CLI, at 160, 300, and 440 mg/kg) and significantly lowered the peak concentrations of tumor necrosis factor alpha and interleukin-1beta (IL-1beta) in serum. However, the peak concentrations of IL-6 in the sera of CLI-treated mice were higher than in control mice. Our findings suggest that CLI alters LPS-induced inflammatory cytokine production and suppresses endotoxin-induced mortality in this murine model.

Animals↗
PubMed2001

Type I Helicobacter pylori lipopolysaccharide stimulates toll-like receptor 4 and activates mitogen oxidase 1 in gastric pit cells.

Guinea pig gastric pit cells express an isozyme of gp91-phox, mitogen oxidase 1 (Mox1), and essential components for the phagocyte NADPH oxidase (p67-, p47-, p40-, and p22-phox). Helicobacter pylori lipopolysaccharide (LPS) and Escherichia coli LPS have been shown to function as potent activators for the Mox1 oxidase. These cells spontaneously secreted about 10 nmol of superoxide anion (O(2)(-))/mg of protein/h under LPS-free conditions. They expressed the mRNA and protein of Toll-like receptor 4 (TLR4) but not those of TLR2. LPS from type I H. pylori at 2.1 endotoxin units/ml or higher stimulated TLR4-mediated phosphorylations of transforming growth factor beta-activated kinase 1 and its binding protein 1 induced TLR4 and p67-phox and up-regulated O(2)(-) production 10-fold. In contrast, none of these events occurred with H. pylori LPS from complete or partial deletion mutants of the cag pathogenicity island. Lipid A was confirmed to be a bioactive component for the priming effects, while removal of bisphosphates from lipid A completely eliminated the effects, suggesting the importance of the phosphorylation pattern besides the acylation pattern for the bioactivity. H. pylori LPS is generally accepted as having low toxicity; however, our results suggest that type I H. pylori lipid A may be a potent stimulator for innate immune responses of gastric mucosa by stimulating the TLR4 cascade and Mox1 oxidase in pit cells.

Adaptor Proteins, Signal Transducing↗
PubMed2001

Hepatocellular carcinoma: involvement of the internal mammary artery.

PURPOSE: To investigate factors related to the development of internal mammary arteries (IMAs) as feeding arteries of hepatocellular carcinomas (HCCs). MATERIALS AND METHODS: In 30 patients with HCC located in ventral hepatic areas directly beneath the diaphragm, bilateral internal mammary arteriography was performed to explore involvement of the IMA with HCC. The number of previous transcatheter arterial embolizations (TAEs), tumor size, time from initial TAE to IMA angiography, inferior phrenic artery (IPA) involvement with tumor, presence of hepatic artery occlusion, and use of other treatments were compared in groups with and without involvement of the IMA. RESULTS: The group with IMA involvement included 10 patients; the group without involvement, 20 patients. TAE had been performed two to 12 times in the group with involvement and zero to six times in the group without involvement (P =.01). Mean tumor sizes in these two groups were 5.1 and 6.0 cm, respectively; hepatic artery occlusion was noted in nine and zero patients (P =.01) in the two groups. The time from initial TAE to IMA angiography ranged from 3 to 53 months (median, 31.5 months) and from zero to 89 months (median, 0 months) (P =.01). IPA involvement was observed in seven and four patients (P =.015). CONCLUSION: These results strongly suggest that, regardless of tumor size, when HCCs are located in the ventral hepatic areas directly beneath the diaphragm, the IMAs serve as feeding arteries in patients with hepatic artery occlusion caused by repeated TAE.

Aged↗
PubMed2001

Interleukin-1beta enhances retinoic acid-mediated expression of bone-type alkaline phosphatase in rat IEC-6 cells.

We previously showed that vitamin A upregulated the expression of bone-type alkaline phosphatase (ALP) in fetal rat small intestine and rat intestinal IEC-6 cells. In this study, we examined interactions between retinoic acid (RA) and several growth factors/cytokines on the isozyme expression in IEC-6 cells. Epidermal growth factor and interleukins (ILs)-2, -4, -5, and -6 completely blocked the RA-mediated increase in ALP activity. In contrast, IL-1beta markedly increased the activity, protein, and mRNA of the bone-type ALP only when RA was present. IL-1beta and/or RA did not change the type 1 IL-1 receptor transcript level, whereas IL-1beta enhanced the RA-induced expressions of retinoic acid receptor-beta (RAR-beta) and retinoid X receptor-beta (RXR-beta) mRNAs and RA-mediated RXR response element binding. The synergism of IL-1beta and RA on ALP activity was completely blocked by protein kinase C (PKC) inhibitors. Our results suggest that IL-1beta may modify the ALP isozyme expression in small intestinal epithelial cells by stimulating PKC-dependent, RAR-beta- and/or RXR-beta-mediated signaling pathways.

Alkaline Phosphatase↗
PubMed2001

Helicobacter pylori lipopolysaccharide induces apoptosis of cultured guinea pig gastric mucosal cells.

Helicobacter pylori lipopolysaccharide (LPS) is generally accepted as a low-toxicity virulence. Primary cultures of guinea pig gastric mucosal cells expressed the Toll-like receptor 4 and were sensitive to H. pylori LPS as well as Escherichia coli LPS. H. pylori LPS stimulated phosphorylation of transforming growth factor-beta-activated kinase 1 (TAK1), TAK1-binding protein 1 (TAB1), and c-Jun NH(2)-terminal kinase (JNK) 2. H. pylori LPS at >2.1 endotoxin unit/ml (>1 ng/ml) activated caspase-8, stimulated cytochrome c release from mitochondria, and subsequently activated caspases-9 and -3, leading to apoptosis. Epidermal growth factor blocked all of these apoptotic processes and inhibited apoptosis, whereas it did not modify the phosphorylation of TAK1, TAB1, and JNK2. A comparatively specific inhibitor of caspase-8 or -9 blocked apoptosis, whereas cytochrome c release was prevented only with a caspase-8-like inhibitor. Our results suggest that caspase-8 and mitochondria may play crucial roles in H. pylori LPS-induced apoptosis and that this accelerated apoptosis may be involved in abnormal cell turnover of H. pylori-infected gastric mucosa.

Animals↗
PubMed2001

Use of human recombinant DNase I expressed in COS-7 cells as an immunogen to produce a specific anti-DNase I antibody.

To obtain human deoxyribonuclease I (DNase I) as an immunogen, we have developed a procedure that is more useful and effective than the conventional procedure, which uses human urine as a starting material. In the new procedure, we culture COS-7 cells transfected with expression vector carrying human DNase I cDNA, and then purify the enzyme from the culture medium. The enzyme can be easily isolated to apparent homogeneity by passage through only three chromatography columns. The rabbit antiserum that we used against the recombinant DNase I was not inferior to that used against DNase I from human urine, in terms of both its ability to discriminate DNase I phenotypes and its ability to neutralize enzyme activity. Therefore, our procedure may be useful for producing an antibody specific for human DNase I.

Animals↗
PubMed2001

Geographical north-south decline in DNASE1*2 in Japanese populations.

Allele frequencies for human deoxyribonuclease I (DNase I) phenotypes were determined using blood samples from about 2000 Japanese subjects living in nine prefectures, and compared with one another. DNase I phenotyping was performed principally using isoelectric focusing electrophoresis and activity staining. The DNase I system was shown to have enhanced potential for anthropologic, genetic, and clinical studies of Japanese populations. DNase I phenotypes were analyzed to evaluate the degree of genetic variation at the DNASE1 locus. Our examination of DNase I types revealed a decreasing north-to-south gradient in the DNASE1 allele.

Case-Control Studies↗
PubMed2001

Acute myocardial infarction showing total occlusion of right coronary artery and thrombus formation of left anterior descending artery.

A 33-year-old Japanese man had an attack of chest pain associated with ST-segment elevation in the inferolateral leads on his electrocardiogram. Emergency coronary angiography showed total obstruction in the mid right coronary artery (RCA) and a movable thrombus in the proximal left anterior descending artery (LAD). We performed emergency percutaneous transluminal coronary angioplasty (PTCA) for the RCA lesion. The operation was successful and we then conducted intracoronary thrombolysis (ICT) with tisokinase 6,400,000 IU for the LAD thrombus. Its size was reduced by ICT. He had an uneventful hospital course. After 1 month, repeat coronary angiography showed no significant stenosis in the RCA nor thrombus in the LAD. A coronary spasm provocation test was performed using acetylcholine. Coronary spasm in the LAD was induced by an intracoronary injection of 100 microg acetylcholine. In this case, we observed a unique condition suggesting simultaneous double coronary artery occlusion.

Adult↗
PubMed2001

Collaborative study on rat sperm motion analysis using CellSoft Series 4000 semen analyzer.

A collaborative study was conducted to determine useful and sensitive rat sperm motion parameters in a CellSoft Series 4000 semen analyzer to detect the effects of compounds on sperm motion. The effects on the sperm motion parameters were investigated using alpha-chlorohydrin, boric acid, ethinylestradiol, ethyl methanesulfonate, nitrazepam, nitrobenzene, ornidazole, sulfasalazine or valproic acid which are well known to induce reproductive or testicular toxicities. All compounds used in this study decreased percentage of motile sperm (% motile). Curvilinear velocity (VCL), maximum and mean amplitude of lateral head displacement (ALH max and ALH mean) were decreased by treatment with all compounds except for valproic acid. Treatment with alpha-chlorohydrin, ornidazole or sulfasalazine under mid-dosage regimens decreased only these parameters. Beat cross frequency (BCF) was increased by treatment with sulfasalazine. There were some treatments which caused either decreased or increased changes irrespective of dosage regimen in linearity, average radius, percentage of circular-swimming sperm out of motile sperm (circular/motile) and percentage of circular-swimming sperm out of all sperm (circular/all). Based on these results, we concluded that % motile, VCL, ALH max and ALH mean are considered useful and sensitive parameters for evaluating the effects of compounds on sperm motion. A parameter of BCF can be useful to detect the effects of specific compounds on sperm motion. Linearity, average radius, circular/motile and circular/all are not considered useful or sensitive indicators to detect the effects of compounds on sperm motion.

Animals↗
PubMed2001

Hypoglycemia induced by secretion of high molecular weight insulin-like growth factor-II from a malignant solitary fibrous tumor of the pleura.

A 49-year-old woman with a malignant solitary fibrous tumor of the pleura presented with hypoglycemia. Most of the serum insulin-like growth factor II (IGF-II) existed as high molecular weight IGF-II. Furthermore, there were larger amounts of high molecular weight IGF-II found in the tumor cystic fluid than in the serum. After surgical resection of the tumor, high molecular weight IGF-II was not detected in the serum and the hypoglycemia resolved. Immunohistochemically, IGF-II was localized in the so-called Golgi area of the tumor cell. These findings suggest that hypoglycemia in this patient was caused by the high molecular weight IGF-II produced by the tumor.

Female↗
PubMed2001

[Visualization of abdominal arteries by super-high-flow venous injection using multidetector helical CT].

The purpose in this study was to compare the ratio of visualization of upper abdominal arteries using MDHCT between the super-high-flow injection method (Group A) and the conventional injection method (Group B). The subjects ects were 200 patients who were randomly divided into Group A (100 patients) and Group B (100 patients). In Group A, visualization of the large arteries, including the CE, SMA, HA and LGA, was possible at a rate exceeding 96%, and that of the small arteries, including the DPA, SPDA, RGA and Cyst A, was more than 79%. Visualization of upper abdominal arteries was markedly improved by the super high flow injection technique.

Abdomen↗
PubMed2001

[Acute disseminated encephalomyelitis in a 3-month-old infant].

Acute disseminated encephalomyelitis (ADEM) is a demyelinating disease showing multifocal central nervous system lesions due to an autoimmune disorder. We reported a 3-month-old girl with ADEM. One week after having a cold, she presented with somnolence, poor feeding and vomiting. When she was admitted three days after the onset, she could neither fix or follow objects with her eyes nor respond to sound. Her muscle tone was decreased. Cerebrospinal fluid examination revealed pleocytosis, elevated protein concentration and positive myelin basic protein. No oligoclonal band was detected. Diffuse monomorphic slow wave activity was noted on the electroencephalogram. Only wave I was present bilaterally on the auditory brainstem response. T2 weighted images of magnetic resonance imaging revealed multiple areas of high signal in the right posterior limb of the internal capsule, white matter of the cerebellum and brainstem. She was diagnosed as having ADEM, and underwent high dose gamma-globulin therapy. Corticosteroids were not given because of her high blood pressure. The clinical symptoms improved continuously before and after the administration. Two years after the onset, she showed normal growth and development without reoccurrence. The age at onset of childhood ADEM is usually 3 or 4 years. ADEM before one year of age is very rare. The demyelinating lesions of this case corresponded to the regions which normally become myelinated by 3 months. Although ADEM is usually treated with corticosteroids, high dose gamma 1-globulin therapy can be considered if patients are very young or have a high risk for corticosteroid, or respond poorly to corticosteroids.

Drug Administration Schedule↗
PubMed2001

Robotic stabilization that assists cardiac surgery on beating hearts.

Minimally Invasive Direct Coronary Artery Bypass (MIDCAB) requires surgeons the precision of hand skill and the mental concentration, since it needs to work on beating hearts. We propose a surgical robot system that compensates motions of organs during operations. The motion canceling robot system consists of three technologies visual synchronization, motion synchronization and master slave control. In this paper, we verify the effectiveness of the prototype system by in-vivo experiment.

Computer Systems↗
PubMed2001

[Reproductive and developmental toxicity studies of S-1090, cefmatilen hydrochloride hydrate (1)--A study on oral administration prior to and in the early stages of pregnancy in rats].

Cefmatilen hydrochloride hydrate (S-1090) was administered daily by gavage to rats at doses of 100, 300 or 1000 mg potency/kg/day prior to and in the early stage of pregnancy to assess its adverse effects on parental reproductive ability and embryo-fetal development. Loose and/or reddish brown feces were observed in both males and females of all the S-1090 dosing groups, and abdominal distention was also observed in males throughout the dosing period. No drug-related deaths occurred in either males or females. In males, body weight and food consumption were increased at a dose of 1000 mg potency/kg/day throughout the dosing period. In females, body weight gain was restrained during late pregnancy, and food consumption was decreased transiently following the initiation of dosing, and then remained high on the day before parturition in all the S-1090 dosing groups. Necropsy of male and female rats revealed an increase in the cecum weight. The reproductive ability of males and females was normal in all the S-1090 dosing groups. No effects of S-1090 were observed in the implantation ratio, embryo-fetal viability, fetal body weight, and incidence of external, skeletal and visceral anomalies. Based on these results, the no observed adverse effect levels of S-1090 are estimated to be less than 100 mg potency/kg/day for parental general toxicity, 1000 mg potency/kg/day for reproductive toxicity, and 1000 mg potency/kg/day for developmental toxicity in embryo-fetuses under the conditions of the present study.

Administration, Oral↗
PubMed2001

[Reproductive and developmental toxicity studies of S-1090, cefmatilen hydrochloride hydrate (2)--A study on oral administration during the period of organogenesis in rats].

Cefmatilen hydrochloride hydrate (S-1090) was administered daily by gavage to female rats at doses of 100, 300 or 1000 mg potency/kg/day from Days 7 to 17 of pregnancy to assess its effects on dams and on development of the embryo-fetuses and offspring. Loose or reddish-brown feces were observed in dams of all the S-1090 dosing groups. Body weight gain was increased from the early stage of administration to the end of pregnancy, food consumption was transiently decreased at the early stage of administration, and water consumption was increased from the middle to the end of pregnancy in all the S-1090 dosing groups. However, no effects on pregnancy, parturition and lactation were observed. Necrospy revealed an increased cecum weight in pregnant and lactating dams of all the S-1090 dosing groups. No effects of S-1090 were observed in viability, growth, incidences of external, skeletal and visceral anomalies, and degree of ossification in F1 fetuses. No effects of S-1090 were observed in such parameters as viability, incidence of external and skeletal anomalies, physical development, sensory functions/reflexes, behavior and reproductive function in F1 offspring. No adverse effects were observed in F2 offspring. On the basis of these results, the no observed adverse effect levels of S-1090 are estimated to be less than 100 mg potency/kg/day for maternal general toxicity, 1000 mg potency/kg/day for maternal reproductive toxicity and the developmental toxicity in the embryo-fetuses and offspring under the conditions of the present study.

Abnormalities, Drug-Induced↗