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Biomedical subjects

S Shimizu

Publications and source records attributed to S Shimizu.

At least 361 records · Page 20Linked to original sources
PubMed1998

A human myeloid cell line producing stem cell growth factor, KPB-M15, secretes another growth factor active on murine hematopoietic progenitor cells.

Human stem cell growth factor (SCGF) produced by a myeloid cell line, KPB-M15, exhibits species-specific hematopoietic activities. However, KPB-M15-conditioned medium induced colony formation of mouse bone marrow cells. KPB-M15-derived colony-stimulating activity (CSA) was purified through Butyl-Toyopearl 650c and Cu2+ chelating-Sepharose 6B chromatography. TSK-G3000SW gel filtration of the purified preparation presented 3 distinct peaks around Vo, 150 kD and 85 kD. Gel fractions extracted from SDS-PAGE had macrophage colony-stimulating factor (M-CSF)-specific amino acid sequences. PCR, Northern hybridization and ELISA demonstrated that KPB-M15 cells secreted a significant amount of M-CSF and IL-6. Anti-M-CSF but not anti-IL-6 antibody abrogated CSA in KPB-M15-CM. IL-6 hardly synergized with M-CSF to enhance colony formation. Collectively, M-CSF is a sole CSA for murine hematopoietic progenitor cells in KPB-M15-CM. This is the first report of a human myeloid cell line, KPB-M15, constitutively producing M-CSF in addition to SCGF and IL-6. It can be useful in investigating the mechanism of production of M-CSF.

Animals↗
PubMed1998

Escherichia coli transformant expressing the glucose dehydrogenase gene from Bacillus megaterium as a cofactor regenerator in a chiral alcohol production system.

Escherichia coli JM109 (pGDA2) overexpressing the glucose dehydrogenase (GDH) gene from Bacillus megaterium IWG3 was examined for use as a cofactor regenerator. In the asymmetric reduction of ethyl 4-chloro-3-oxobutanoate by E. coli JM109 (pKAR) which is an aldehyde reductase-overproducing transformant, E. coli JM109 (pGDA2) can act as an NADPH regenerator with NADP+ and glucose, similarly to commercially available GDH.

Alcohols↗
PubMed1998

Purification and characterization of NADPH-dependent carbonyl reductase, involved in stereoselective reduction of ethyl 4-chloro-3-oxobutanoate, from Candida magnoliae.

A NADPH-dependent carbonyl reductase was purified to homogeneity from Candida magnoliae AKU4643 through four steps, including Blue Sepharose affinity chromatography. The enzyme catalyzed the stereoselective reduction of ethyl 4-chloro-3-oxobutanoate to the corresponding (S)-alcohol with a 100% enantiomeric excess, which is a useful chiral building block for the chemical synthesis of pharmaceuticals. The relative molecular mass of the enzyme was estimated to be 76,000 on high performance gel filtration chromatography and 32,000 on SDS polyacrylamide gel electrophoresis. The enzyme reduced alpha-, beta-keto esters and conjugated diketones in addition to ethyl 4-chloro-3-oxobutanoate. The enzyme activity was inhibited by quercetin and HgCl2, but not by EDTA. The N-terminal amino acid sequence of the enzyme showed no apparent similarity with those of other oxidoreductases.

Acetoacetates↗
PubMed1998

Cloning genomic DNA encoding apple polyphenol oxidase and comparison of the gene product in Escherichia coli and in apple.

Two PCR-amplified genomic DNA fragments encoding apple (cv. Fuji) polyphenol oxidase (PPO) were cloned and sequenced. A comparison of genomic DNA with cDNAs revealed that the PPOs lacked introns. Both PPO DNAs appear to encode a 66-kDa precursor protein consisting of a 56-kDa mature protein and a N-terminal transit peptide of 10-kDa N-terminal transit peptide. Apple PPO DNA was expressed in Escherichia coli, and the gene product (56 kDa) without a transit peptide was immunochemically detected and was the same size (ca. 65 kDa) as the main PPO of apple fruit by SDS-PAGE.

Amino Acid Sequence↗
PubMed1998

Role of tetrahydrobiopterin in the function of nitric oxide synthase, and its cytoprotective effect (Review).

This review discusses the role of (6R)-5,6,7,8-tetrahydrobiopterin (H4 biopterin) in the function of nitric oxide synthase (NOS), and the protective effect of H4 biopterin against nitric oxide (NO)- and/or reactive oxygen species-induced cytotoxicity. Although NOS releases NO, which regulates vascular tone and immune surveillance under normal conditions, NOS seems to produce superoxide anion and hydrogen peroxide when H4 biopterin, one of the cofactors, or L-arginine, a substrate, is decreased, suggesting the possibility that NOS is a source of reactive oxygen species under pathological conditions. Moreover, simultaneous release of NO and reactive oxygen species in the presence of suboptimal concentrations of H4 biopterin and/or L-arginine may be highly toxic, since NO reacts with superoxide anion and hydrogen peroxide to form peroxynitrite, singlet oxygen and the hydroxyl radical, which are toxic. An increase in H4 biopterin content in cells obviates NOS dysfunction (production of reactive oxygen species instead of NO) and protects the cells against NOS dysfunction-related cell injury. Moreover, H4 biopterin has a strong scavenging activity for reactive oxygen species, and inhibits thier cytotoxicity. H4 biopterin is also likely to reduce NO-induced cytotoxicity. Thus, H4 biopterin is not only an important regulator of NOS function, but is also an intracellular antioxidant. NO and reactive oxygen species are known to be implicated in the development of many pathological states. It is possible that H4 biopterin could be effective for treating many diseases, such as ischemia-reperfusion injury, inflammation and diabetes mellitus.

Biopterins↗
PubMed1998

Immunoblot analysis of humoral immune responses to Leucocytozoon caulleryi in chickens.

The humoral antibody responses of chickens infected or immunized with Leucocytozoon caulleryi were analyzed by immunoblot comparing with protection against challenge infection, agar-gel precipitation (AGP) test, enzyme-linked immunosorbent assay (ELISA), and parasitemia. IgG antibodies in the sera from chickens infected with L. caulleryi were found to react with 20-35 bands of approximate molecular weights 25-300 kDa, such as 33, 44, 58, 79, 94, and 141 kDa from 3 to 50 wk after infection. In chickens immunized with schizont antigens from L. caulleryi, several bands were reacted with sera 2 wk after the second immunization, e.g., 36, 58, 71, 81, 97, 112, and 123 kDa. Chickens that recovered from the primary infection showed complete protection against reinfection, whereas immunized chickens showed partial protection against challenge infection. These results suggest that the difference in antibody response to schizont antigen might cause the difference in protection between immunized and infected chickens.

Animals↗
PubMed1998

Hepatolithiasis: outcome of cholangioscopic lithotomy and dilation of bile duct stricture.

BACKGROUND: Cholangioscopic lithotomy (CSL) for hepatolithiasis, a minimally invasive procedure, has a place in complicated or recurrent hepatolithiasis. CSL itself, however, carries inherent risk for recurrence. We analyzed follow-up data after CSL for primary or repeat hepatolithiasis to determine the frequency of recurrence. METHODS: This retrospective analysis includes 21 patients with hepatolithiasis admitted to the hospital from September 1992 to December 1995 who underwent CSL. Through a percutaneous biliary drainage route, cholangioscopy was inserted to remove calculi with basket forceps or electrohydraulic lithotripter. Stenotic ducts, defined as less than 2 mm in diameter, were dilated with silicone rubber stenting or a balloon dilator. RESULTS: Ten patients were treated for primary hepatolithiasis and 11 for repeat hepatolithiasis. Of the patients with primary hepatolithiasis, one died of complications and the other nine patients underwent complete lithotomy. Among 11 patients who had repeat hepatolithiasis, four had undergone hepatectomy for hepatolithiasis and two previous CSLs; 10 patients (91%) underwent complete lithotomy. During the follow-up, four (40%) of the 10 patients with biliary stenosis at the time of cholangioscopic treatment showed recurrent calculi, whereas all eight patients without stricture had uneventful courses. Of the 19 patients who underwent complete lithotomy, calculi recurred in four (21%), three cases of which recurred less than 1 year after CSL. CONCLUSIONS: Against hepatolithiasis of primary and postoperative repeat cases, CSL can allow complete lithotomy. The bile duct stricture, however, carries a high risk for recurrent calculi; hence, permanent relief of stricture is mandatory.

Adult↗
PubMed1998

[The antimicrobial susceptibilities and serotypes of Pseudomonas aeruginosa isolated from sputum].

During the period of January 1992 and August 1995, 75 strains of Pseudomonas aeruginosa were isolated from sputum at the Hiroshima Prefectural Hiroshima Hospital. The antimicrobial susceptibilities and serotypes of those strains were investigated. The results are summarized as follows: 1. The analyses of antimicrobial susceptibilities revealed that meropenem (MEPM) was the most active among the carbapenems tested against those P. aeruginosa strains with MIC of < or = 6.25 micrograms/ml. All of the strains were thus found to be susceptible to MEPM, while 9 strains out of 75 (12%) were resistant to imipenem showing cross-resistance to biapenem. 2. The activities of the beta-lactams other than carbapenems were found to be the order of cefozopran > or = ceftazidime > aztreonam > piperacillin with MIC50 and MIC90 ranging of 3.13-6.25 micrograms/ml and 25- > or = 100 micrograms/ml, respectively. 3. Among aminoglycosides tested, 3 strains (4.0%) of the strains showed resistance to amikacin, however none of them were resistant to tobramycin. 4. Distribution of serotypes among the strains was; type G 22.7%, type M 21.3%, type A 16.0%, type B 13.3% and type E 8.0%. Strains of types M and E showed multiple resistance to beta-lactams except carbapenems. As documented in this study, the frequency of isolation of beta-lactam-resistant P. aeruginosa (including carbapenem-resistant) is steadily increasing. Continuous surveillance of antimicrobial susceptibility among clinically isolated P. aeruginosa seems to be necessary.

Anti-Bacterial Agents↗
PubMed1998

[Construction of illegal drug images and mass media in Japan].

This study attempts to clarify the drug problem of Japan in terms of images of illegal drugs (stimulants, marijuana, and volatile solvents) by comparing (1) different types of drugs and (2) differences between generations. Another objective of this research was to examine influence by the mass media reports with regard to drug incidents which influence upon image formation of illegal drugs among people. In this study 488 males from the city of Osaka were chosen by a random sampling method and a door to door survey was undertaken utilizing a self-administered questionnaire with a partial interview method. It was revealed that as a whole negative images such as "dangerous" and "terrible" were still widely prevailing and positive image such as "fashionable" was much less prevailing. Specially, stimulants were regarded more dangerous compared to marijuana and volatile solvents. In contrary, marijuana was regarded more fashionable compared to stimulants and volatile solvents. Volatile solvents were considered more "intimate" compared to other drugs. With regard to generation differences, it was the youth who possessed more positive images towards marijuana and more intimate feelings about volatile solvents than other generations. Findings show that with regard to news about illegal drug incidents, respondents' appraisal of the news of mass media primarily make significant influence, as compare to mere cognition, on images of illegal drugs. Furthermore, it was revealed that there was likely to result in positive images of illegal drugs due to lack of adequate information. From the aspects of education, it was suggested that dissemination of information at a vast range and maintenance of negative images might become a crucial task.

Adult↗
PubMed1998

[Clear cell ependymoma--a case report].

A case of intraaxial clear cell ependymoma is reported. A 46-year-old man complained of right hemiparesis. CT scan showed a mass lesion on the median plane with a huge cyst in the left frontal lobe. MRI showed an iso-low intensity mass by T1-weighted image. The tumor was heterogeneously enhanced by Gd-DTPA and the wall was enhanced as well. Angiogram revealed a tumor stain from the right internal carotid artery. The main mass of the tumor was totally removed but the cystic wall was left removed. Histopathological examination revealed clear cell ependymoma. Immunohistochemical examination revealed that, although vimentin and NSE were positive, GFAP, synaptophysin and S-100 were negative. Ultrastructual examination revealed cilia, microvilli and desmosomal junctions. The patient fully recovered after operation and showed no sign of recurrence after an year of follow-up. Clear cell ependymoma is a rare variant of ependymoma. Ultrastructual examination was more useful than immunohistochemical examination for diagnosis.

Brain Neoplasms↗
PubMed1998

[Clinical and bacteriological studies on panipenem/betamipron in pediatrics. Kanagawa Research Group for Infectious Diseases of Children].

Following its introduction into the market, PAPM/BP (panipenem/betamipron) was clinically studied in 188 evaluable cases out of 207 cases primarily of respiratory infectious diseases treated at the pediatric departments of 15 hospitals. In the clinical evaluation, the drug proved effective in three of three cases of sepsis; three of three cases of suppurative meningitis; nine of ten cases of laryngopharyngitis, six of seven cases of tonsillitis, 56 of 63 cases of acute bronchitis, 90 of 98 cases of pneumonia, and one of one case of phyothorax, all of which are respiratory infectious diseases; one of one case of secondary infection of a chronic respiratory disease; and two of two cases of lymphadenitis, which is a disease of the soft dermal structure. The overall efficacy rate was 91.0% (171/188 cases). In the bacteriological study, Gram-positive bacteria were eliminated in five of five strains of S. aureus, 30 of 31 strains of S. pneumoniae (96.8%), and three of three strains of S. pyogenes. Gramnegative bacteria were eliminated in 15 of 17 strains of H. influenzae (88.2%), three of four strains of M. catarrhalis, and two of two strains of K. pneumoniae. The overall elimination rate was 92.1% (70/76 strains). In the 23 strains of S. pneumoniae that were examined, penicillin-resistant strains accounted for 56.5%, showing an elimination rate of 100%. No serious adverse effects were observed, and the incidence of adverse effects was 1.45%. As for abnormalities in laboratory tests, levels of GOT and GPT increased in eight cases (3.88%), LDH increased in one case (0.48%), and neutropenia occurred in one case (0.51%). These results suggest that PAMP/BP could be considered the first choice in the treatment of infectious diseases in pediatrics, due to its effectiveness and high level of safety.

Adolescent↗
PubMed1998

[Coordination or competence: an emerging problem in the development of network treatment for alcoholics].

The author recognizes the significance and relevance of the network treatment for alcoholics is such a way as an effort to respond not only to the medical needs but also to social service needs, in order to support the recovery of alcoholics. Consequently we are faced to an indispensable task to look back historically the developmental process of the treatment service for alcoholics in Japan. A recent policy development in the alcohol treatment is stimulating the shift from the overweight medical approach to a more comprehensive approach including social services. This innovation is bringing about not only a wider treatment options but also a newly emerging problem of "coordination or competence" as well. It was implied in this paper that a concept of "shared function" is promising to consider this new problem.

Alcoholism↗
PubMed1998

Pancreatic carcinoma in remnant pancreas after pancreatectomy for mucinous cystadenoma.

There are very few benign or malignant diseases which arise in the remnant pancreas after pancreatectomy. Pancreatic carcinoma in the remnant pancreas after pylorus preserving pancreatoduodenectomy (PpPD) for mucinous cystadenoma in a 66-year-old Japanese man is reported in this paper. The patient underwent PpPD for a mucinous cystadenoma in the pancreatic head 39 months prior to the present operation. The surgical margins of the PpPD specimen were free from atypical cells. Follow-up ultrasonography revealed a hypoechoic lesion in the body of the remnant pancreas. Magnetic resonance cholangiopancreatography (MRCP) revealed a stenosis of the main pancreatic duct, with upstream dilatation in the remnant pancreas. Segmental resection of the remnant pancreas, splenectomy, pancreaticojejunostomy and intraoperative radiotherapy were performed under the diagnosis of pancreatic carcinoma of the remnant pancreas. Final histopathological diagnosis was adenocarcinoma of the pancreas. There were no malignant cystic components. The present pancreatic carcinoma was regarded as independent of the previous mucinous cystadenoma. Postoperative radiation therapy and chemotherapy were added. He is doing well 20 months after the second operation although diabetes mellitus has slightly deteriorated. In this communication, we would like to recommend that clinicians should constantly be on guard against the development of pancreatic carcinoma even in the remnant pancreas after pancreatectomy for mucinous cystadenoma.

Adenocarcinoma↗
PubMed1998

[Relief of neuropathic pain with intravenous magnesium].

We investigated the effect of intravenous magnesium, a N-methyl-D-asparate (NMDA) receptor antagonist, in 8 patients suffering from neuropathic pain (post herpetic neuralgia or causalgia etc.). After the nerve block, magnesium sulphate (0.5 mol.l-1) 5 ml was administered intravenously by bolus infusion taking 5 min, followed by continuous infusion of the same dose for one hour. All patients were treated with this therapy once a week. In 4 patients, VAS score decreased 3 points or more when this therapy had been administered 3 to 11 times. In 2 patients, VAS score did not change, and the analgesic effect of magnesium was not certain in other 2 patients. Some patients felt heat sensation immediately after the bolus infusion of Mg, and had a good sleep after this therapy. However, there were not any severe side effects and significant change in HR or BP. We conclude that this therapy with magnesium once a week is safe and effective for relieving neuropathic pain.

Aged↗
PubMed1998

Preoperative exocrine pancreatic function predicts risk of leakage of pancreaticojejunostomy.

BACKGROUND: The objective of this study was to clarify the relationship between preoperative exocrine pancreatic function and pancreatic anastomotic leakage after pancreatectomy. METHODS: Fifty-five patients who underwent proximal pancreatectomy with pancreaticojejunostomy were reviewed with regard to preoperative exocrine pancreatic function, size of the main pancreatic duct, postoperative pancreatic juice output, and pancreaticojejunostomy leakage. RESULTS: There were 32 patients with a normal value at the preoperative N-benzoyl-L-tyrosyl-p-aminobenzoic acid (BT-PABA) excretion test (> 70%) and 23 with a low BT-PABA value (< or = 70%). The greatest diameter of the main pancreatic duct in the group with normal BT-PABA results was significantly smaller than that in the group with low BT-PABA results (4.6 +/- 2.7 mm vs 7.1 +/- 4.2 mm; P < .05). The output of pancreatic juice during a 10-day period (from postoperative days 5 through 14) in the group with normal BT-PABA results was significantly higher than that in the group with low BT-PABA results (1738 +/- 898 mL vs 1072 +/- 1174 mL; P < .05). Pancreatic leakage occurred in 8 (25%) of the 32 patients in the group with normal BT-PABA results and in none of the 23 patients in the group with low BT-PABA results (P < .01). CONCLUSIONS: Patients with normal exocrine pancreatic function produce a larger amount of pancreatic juice than those with low exocrine pancreatic function and have a potential risk of anastomotic leakage after pancreatectomy.

4-Aminobenzoic Acid↗