Biomedical subjects

M Ishihara

Publications and source records attributed to M Ishihara.

At least 109 records · Page 6Linked to original sources

PubMed1998

[Ocular tuberculosis].

The frequency of tuberculous uveitis has extremely decreased in Japan. Anterior granulomatous or non-granulomatous uveitis, chorioretinitis and retinal vasculitis are common ocular manifestations, while tuberculoma, scleritis, keratitis and orbital tuberculosis are rare. The diagnosis of ocular tuberculosis is extremely difficult because ocular tuberculosis tends to be negative in chest x-ray or tuberclin skin test. To diagnose ocular tuberculosis clinically some ophthalmologists recommend subconjunctival tuberculin test or therapeutic isoniazide (INH) test. Recently, for confirmed diagnosis, polymerase chain reaction (PCR) technique has been used to detect mycobacterium in intraocular samples such as aqueous or vitreous humor. The mainstay of treatment is antituberculosis agents. Active retinal vasculitis or tuberculoma are generally responsive to corticosteroid therapy. Although ocular tuberculosis is rare, it must be considered as one of the possible causes of uveitis.

Chorioretinitis↗

PubMed1997

Screening of fungal beta-xylanases for production of acidic xylooligosaccharides using in situ reduced 4-O-methylglucuronoxylan as substrate.

Fungal beta xylanases were screened for production of acidic xylooligomers from 4-O-methylglucuronoxylan. In situ reduced hardwood xylan was used as substrate because the products of neutral- and acidic-branched xylooligomers help define substrate specificity of the enzymes. Borohydride reduction in situ transformed 30% of 4-O-methyl-alpha-D-glucopyranosyluronic acid residues into 4-O-methyl-alpha-D-glucopyranosyl residues and reduced C-1 end groups in the xylan backbones. A total of ten beta-xylanase fractions from four fungi were partially purified by chromatography by anion exchange and molecular sieving, and graded qualitatively for enzymatic hydrolysis of the substrate. The yield of acidic xylooligomers was highly affected by whether alpha-glucuronidases were present in the beta-xylanase fractions. Some fractions gave free 4-O-methyl-alpha-D-glucopyranosyluronic acid, but none of the enzyme fractions could release free 4-O-methyl-alpha-D-glucose. Among the beta-xylanase fractions studied, xylanase II of Trichoderma viride was the best producer of aldotetraouronic acid [2-O-(4-O-methyl-alpha-D-glucopyranosyluronic acid)-D-xylotriose]. The results obtained suggested that there was a difference in the steric hindrance of the branch point on fungal beta-xylanases between 4-O-methyl-alpha-D-glucopyranosyl and 4-O-alpha-D-glucopyranosyluronic acid residues.

Basidiomycota↗

PubMed1997

Nucleotide sequence analysis of the HLA class I region spanning the 237-kb segment around the HLA-B and -C genes.

To elucidate the detailed gene organization of the human leukocyte antigen (HLA) class I region on chromosome 6, seven contiguous cosmid genomic clones covering the 237-kb segment around the HLA-B and -C loci were subjected to DNA sequencing by the shotgun strategy to give a single contig of 236,822 bp from the MICA gene (58.2 kb centromeric of HLA-B) to 90.8 kb telomeric of HLA-C. This region was confirmed to contain four known genes, MICA, HLA-17, HLA-B, and HLA-C, from centromere to telomere. Further, a new member of the P5 multicopy genes was found to be about 1.3 kb upstream of the HLA-17 gene and designated P5.8. Five novel genes designated NOB1-5 were identified by RT-PCR and Northern blot hybridization. In addition, two pseudogenes, dihydrofolate reductase pseudogene (DHFRP) and ribosomal protein L3 homologous gene (RPL3-Hom), were also found in the vicinity of the HLA-B and -C genes, respectively. The two segments (about 40 kb) downstream of the HLA-B and HLA-C genes showed high sequence homology to each other, suggesting that segmental genome duplication including the major histocompatibility complex (MHC) class I gene must have occurred during the evolution of the MHC.

Blotting, Northern↗

PubMed1997

Usefulness of directional coronary atherectomy in patients with acute anterior myocardial infarction.

To assess the usefulness of directional coronary atherectomy (DCA) in acute myocardial infarction (AMI), 139 consecutive patients with anterior wall AMI undergoing successful catheter intervention were studied. The reocclusion rate was significantly lower in the last 70 patients who underwent DCA as aggressively as possible compared with the first 69 patients treated with coronary balloon angioplasty (12.1% vs 3.0%, p <0.05).

Aged↗

PubMed1997

Structure of fucose branches in the glycosaminoglycan from the body wall of the sea cucumber Stichopus japonicus.

Fucose-branched chondroitin sulfate E was prepared from the body wall of sea cucumber Stichopus japonicus. The purified glycosaminoglycan (GAG) was chemically desulfated, followed by carboxyl reduction. Intact, desulfated, and desulfated/carboxyl-reduced GAG fractions were subjected to per-O-methylation. GC-MS analyses of the resultant partially methylated alditol acetates demonstrated that the fucose branch is formed by two fucopyranosyl residues linked glycosidically through position (1-->3), and that the fucose branch and glucuronic acid are almost equimolar. In addition, it was elucidated that about 20% of the branches stretch from O-3 position of a glucuronic acid moiety of the core chondroitin sulfate polymer, while remaining fucose branches are postulated to protrude from O-4 and/or O-6 position(s) of a N-acetylgalactosamine moiety. This fucose branch was also confirmed to be highly sulfated according to six kinds of substitution pattern in methylation analysis.

Acetylgalactosamine↗

PubMed1997

Face immersion increases vagal activity as assessed by heart rate variability.

We examined whether the diving reflex without breath-holding (face immersion alone) increases vagal activity, as determined by heart rate variability. A group of 15 men [mean age 20 (SD 3) years, height 172 (SD 5) cm, body mass 68 (SD 9) kg] performed 12 trials at various breathing frequencies (5, 10, 15, 20, 30 breaths x min(-1) and uncontrolled breath) with or without face immersion. The R-R intervals of the ECG and gas exchange variables were recorded during the 2 min of each trial. The subjects immersed their faces in 8 10 degrees C water while breathing through a short snorkel. The subject sat in the same position either with or without face immersion. The mean R-R interval (RRmean), standard deviations (SD[RR]) and coefficient of variance (CV[RR]) of the R-R interval were calculated from the R-R intervals during 30-120 s. The face immersion significantly increased SD(RR) and CV(RR) (P < 0.05), and increased RRmean (P < 0.05) at 20 breaths x min(-1). Face immersion itself had no effect on oxygen uptake, tidal volume, end-tidal O2 and CO2 partial pressures. The diving reflex without breath-holding increased the heart rate variability, indicating that face immersion alone increases vagal activity.

Adult↗

PubMed1997

Directional coronary atherectomy for the treatment of acute myocardial infarction.

Directional coronary atherectomy (DCA) was performed after intracoronary thrombolysis in 32 patients with a first acute myocardial infarction. DCA was successful in 31 (97%) of 32 patients. Abrupt closure of the treated segment occurred in one patient but was managed successfully by conventional balloon angioplasty. Repeat angiography was performed in 32 patients before discharge (2.7 +/- 0.7 weeks later) and in 29 patients during the follow-up (4.5 +/- 1.5 months later). No restenosis (stenosis > 50%) occurred before discharge; however restenosis occurred in 12 (41%) of 29 patients during follow-up. The restenosis rate in patients with subintimal resection was significantly higher than in those with intimal resection (78% vs 25%, p < 0.01). These data suggest that DCA in patients with acute myocardial infarction is feasible for persistent early patency of the infarct-related coronary artery, but late restenosis continues to limit success and subintimal resection may increase the restenosis rate during the follow-up.

Aged↗

PubMed1997

Clinical implications of cigarette smoking in acute myocardial infarction: acute angiographic findings and long-term prognosis.

This study was undertaken to assess whether reperfusion in smokers could be achieved spontaneously or therapeutically and to assess whether favorable outcome in smokers could be sustained for years after infarction. We studied 260 patients with anterior myocardial infarction who underwent coronary angiography and thrombolysis within 24 hours after the onset of chest pain. There were 158 smokers and 102 nonsmokers. Smoking was associated more with men, younger age, and less multivessel disease. On initial angiography, the distribution of Thrombolysis in Myocardial Infarction grade was similar between smokers and nonsmokers. After thrombolysis, Thrombolysis in Myocardial Infarction grade 3 was more frequent in smokers (32% vs 18%; p = 0.004). In-hospital mortality rates were lower (8% vs 18%; p = 0.022) and long-term cardiac survival was better in smokers (5-year survival: 82% vs 70%; p = 0.022). Our data demonstrated that the infarct artery of smokers responded more efficiently to thrombolysis and favorable outcome in smokers was sustained throughout 5 years.

Aged↗

PubMed1997

Implications of prodromal angina pectoris in anterior wall acute myocardial infarction: acute angiographic findings and long-term prognosis.

OBJECTIVES: This study was undertaken to assess how prodromal angina affects long-term prognosis after acute myocardial infarction. BACKGROUND: Although it has been reported that prodromal angina occurring shortly before the onset of acute myocardial infarction has protective effects against ischemia, its implication for long-term prognosis remains unclear. METHODS: We studied consecutive 350 patients with anterior myocardial infarction who underwent coronary angiography within 24 h after the onset of chest pain. Follow-up was achieved for 340 patients (97%). RESULTS: Eighty-nine patients had one or more episodes of angina within 24 h before infarction. On initial angiography, patients with prodromal angina in the 24 h before infarction had a patent infarct-related artery more frequently than did those without prodromal angina (34% vs. 22%, p = 0.03). Among 213 patients who underwent thrombolytic therapy for an occluded infarct-related artery, reperfusion was more frequently achieved in patients with prodromal angina in the 24 h before infarction (76% vs. 56%, p = 0.01). Prodromal angina in the 24 h before infarction was associated with a lower in-hospital mortality rate (6% vs. 14%, p = 0.02) and better 5-year survival (p = 0.009). There was no significant difference in survival between patients with previous angina at any time (n = 202) and those without. Multivariate analysis showed that prodromal angina in the 24 h before infarction was an independent factor related to 5-year survival after acute myocardial infarction (odds ratio 0.49, p = 0.04). CONCLUSIONS: Prodromal angina occurring shortly before the onset of infarction, but not previous angina itself, has a beneficial effect on long-term prognosis after infarction, suggesting a relation to ischemic preconditioning.

Aged↗

PubMed1997

Genetic influences on sarcoidosis.

To investigate the genetic influences underlying the development of sarcoidosis, HLA class II genotyping was performed in Japanese patients with sarcoidosis and healthy controls using the PCR-RFLP method. The frequencies of both DR52 group antigen-associated alleles (HLA-DRB1*11, -DRB1*12 and -DRB1*14) and DRB1*08 alleles were higher in the patient group, suggesting that the common, specific amino acid residue on the DRB1 molecule of these alleles may determine susceptibility to sarcoidosis. Alternatively, it is possible that another susceptibility gene, linked to these DRB1 alleles, exists within the MHC region. We screened the TNFA, TNFB, HSP70-1 and Hum70t genes around the class III region, as well as the HLA-DMA and -DMB genes in the class II region, for genetic polymorphism in sarcoidosis. None of these genes suggested a susceptibility to sarcoidosis. These studies support the thesis that one of the major genetic factors controlling the development of sarcoidosis is located within the DRB1 locus in the HLA class II region.

Cytokines↗

PubMed1997

Importance of 2-O-sulfate groups of uronate residues in heparin for activation of FGF-1 and FGF-2.

Complete drying of heparin with various concentrations of NaOH by lyophilization caused specific 2-O-desulfation to various degrees without detectable depolymerization or other chemical changes. In order to assess the importance of 2-O-sulfate groups in uronate residues to promote FGF-1 and FGF-2 activities, various 2-O-desulfated (2-O-DS-) heparins were quantitatively examined for their effects on FGF-1 and FGF-2-induced proliferation of BALB/c3T3 clone A31 (A31) cells and the chlorate-treated cells. Twenty-seven percent or less loss to the 2-O-sulfate groups had no effect on the ability to activate both FGF-1 and FGF-2, while 44% loss resulted in a significant loss of the ability. Complete loss of the ability was observed in 2-O-DS-heparins with 75% or more 2-O-desulfation. These results suggest that a high content of 2-O-sulfate groups in uronate residues of heparin is required for activation of both FGF-1 and FGF-2.

3T3 Cells↗

PubMed1997

Analysis of allelic variation of the TAP2 gene in sarcoidosis.

Sarcoidosis is a systemic granulomatous disease and the DRB1 gene of the DR subregion has been implicated for determining the genetic susceptibility to the disease. We evaluated the allelic variation of the TAP2 gene using the PCR-RFLP method as well as the mismatched PCR-RFLP method in 82 Japanese patients with sarcoidosis and 92 healthy controls. A new allele, TAP2*0103 and a new polymorphic variation at codon 577 in addition to TAP2*0101, TAP2*0102 and TAP2*0201 have been recognized in the Japanese subjects. No significant differences were observed in the frequencies of any TAP2 alleles or dimorphism at codon 577 between the patients and healthy controls. Polymorphic variation of the TAP2 gene does not confer the susceptibility to sarcoidosis.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1997

A strong association between HLA-B*5101 and Behçet's disease in Greek patients.

Behçet's disease is known to be associated with HLA-B51, one of the split antigens of HLA-B5, among many different ethnic groups. In a Greek population, an increased incidence of HLA-B5 in the patient group has also been reported. Because the B51 antigen has been recently identified to comprise seven alleles, B*5101-B*5107, we performed HLA-B51 allele genotyping by the PCR-SSP method as well as serological HLA-A and -B typing among 31 Greek patients with Behçet's disease to investigate whether there is any correlation between one particular B51-associated allele and Behçet's disease. The frequency of B51 was remarkably high (80.6%) in the patient group as compared to the ethnically matched control group (26.7%). In addition, HLA-A26 was also increased in the patients (29.0%) as compared with the healthy controls (3.3%). B51 allele genotyping revealed that all these B51-positive patients carried B*5101. This study revealed a strong association of Behçet's disease in Greeks with one of the B51 subantigens, providing insight into the molecular mechanism underlying an HLA association with Behçet's disease.

Behcet Syndrome↗

PubMed1997

Major histocompatibility complex class II alleles in Kazak and Han populations in the Silk Route of northwestern China.

Genetic polymorphism of the HLA class II loci including the DRB1, DQA1, DQB1 and DPB1 genes was investigated by the polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) method in a Kazak population inhabiting the most northwestern part of China, Urümqi in the Xinjiang Uygur Zizhiqu as well as in a Han population in the same area. Forty-two Kazak and 59 Han unrelated volunteers were enrolled in this study. Among 51 DRB1 alleles tested, 29 alleles were detected, and DRB1*0301 (13.1%) and DRB1*07 (10.7%) in Kazak and DRB1*0901 (11.9%), DRB1*1501 (11.0%) and DRB1*07 (11.0%) in northwestern Han were highly predominant. In 8 DQA1 alleles detected, DQA1*0501 (29.8%) and DQA1*0301 (23.8%) in Kazak, and DQA1*0301 (28.8%) and DQA1*0102 (19.5%) in northwestern Han were the most and the second most common alleles, respectively. Of 18 DQB1 alleles tested, 14 were observed, among which DQB1*0201 and DQB1*0301 were very frequent both in Kazak (23.8% and 21.4%, respectively) and northwestern Han (18.6% and 16.9%, respectively) populations. Of 37 DPB1 alleles tested, 14 were detected. Among them, the frequencies of DPB1*0401 (21.4%), DPB1*0501 (20.2%), DPB1*0402 (19.0%) and DPB1*0201 (16.7%) in Kazak, and those of DPB1*0501 (38.1%) and DPB1*0201 (16.1%) in northwestern Han were highly increased. Several three-locus haplotypes were recognized to predominate significantly, namely DRB1*0301-DQA1*0501-DQB1*0201 (13.1%) and DRB1*0701-DQA1*0201-DQB1*0201 (8.3%) in Kazak; and DRB1*0901-DQA1*0301-DQB1*0303 (11.9%) and DRB1*0701-DQA1*0201-DQB1*0201 (10.2%) in northwestern Han. The dendrogram constructed by the neighbor-joining (NJ) method based on the allele frequencies of the DRB1, DQA1, DQB1 and DPB1 genes of 12 representative populations all over the world including northern Han, southern Han, Manchu and Japanese suggested that Kazak and northwestern Han were the closest to each other, but Kazak was a little farther from the Asian ethnic groups than northwestern Han.

Alleles↗

PubMed1997

Genetic polymorphism in intron 6 of the LMP7 gene in Japanese and its association with sarcoidosis.

Genetic polymorphism in intron 6 of the LMP7 gene was investigated using polymerase chain reaction-restriction fragment length polymorphism in 90 unrelated healthy Japanese controls and 66 Japanese patients with sarcoidosis. Four alleles, including two new ones recently identified in Koreans, LMP7*C and LMP7*D, were found in the Japanese population. The frequency of LMP7*C in the sarcoidosis patients was higher than in the healthy controls. However, this difference might be explained by a secondary association with HLA-DRB1*08 in the HLA-DRB1 gene, which is thought to be the gene primarily responsible for susceptibility to sarcoidosis.

Alleles↗

PubMed1997

Clinical features of patients with chronic liver disease associated with hepatitis C virus genotype 1a/I in Okinawa, Japan.

The clinical characteristics of chronic hepatitis C virus (HCV) carriers with HCV genotype 1a/I infection were investigated and compared with those of chronic HCV carriers infected with 1b/II, 2a/III, 2b/IV and the mixed type of infection. We found that 16 of 408 (3.9%) carriers had HCV genotype 1a infection, comprising four of 67 (6.0%) blood donors, 11 of 263 (4.2%) patients with chronic hepatitis and one of 39 (2.6%) patients with liver cirrhosis. Three of 408 subjects had a mixed infection of genotypes 1a/I and 1b/II. All carriers with genotype 1a (including those with the mixed infection) were of Japanese origin and all, except one who was born in Brazil, were born in Okinawa Prefecture. Nine of 14 patients infected with genotype 1a for whom medical records were obtained had a history suggestive of infection through blood exposure; six had had blood transfusions, one had tattoos, one is a nurse and one had a history of drug addiction. There were no haemophiliacs or other multitransfused patients in the genotype 1a group. Of 10 patients infected with genotype 1a who received interferon (IFN) therapy, four (40%) showed a complete response. Although the small number of patients infected with genotype 1a in the present study precluded statistical analysis of the response to IFN, the response in patients with genotype 1a was better than the response in those infected with genotype 1b and poorer than the response in those patients infected with genotype 2a/III or 2b/IV.

Adult↗

PubMed1997

Effects of various doses of intracoronary verapamil on coronary resistance vessels in humans.

To investigate the vasodilatory effect of various doses of intracoronary verapamil on coronary resistance vessels, we studied 13 patients with normal angiograms. A coronary Doppler guide wire was inserted into the left anterior descending coronary artery, and coronary blood flow velocity (CBFV) was measured. Verapamil was injected into the left coronary artery at doses of 0.1 mg, 0.5 mg, 1.0 mg, and 2.0 mg at 10-min intervals. Nitroglycerin was also injected into the same artery to avoid changes in cross-sectional area. As a measure of coronary vascular resistance, coronary vascular resistance index (CVRI) was calculated as the quotient of mean aortic pressure/CBFV. An injection of verapamil produced a dose-dependent increase in CBFV: 79 +/- 38% with 0.1 mg, 131 +/- 56% with 0.5 mg, 143 +/- 46% with 1.0 mg, and 128 +/- 47% with 2.0 mg of verapamil. The percent peak decreases in CVRI were dose dependent: -42 +/- 13% with 0.1 mg, -50 +/- 17% with 0.5 mg, -62 +/- 14% with 1.0 mg, and -60 +/- 9% with 2.0 mg of verapamil. Thus, intracoronary verapamil produces a dose-dependent dilation of coronary resistance vessels, and the optimal effect is produced with an injection of verapamil at a dose of 1.0 mg into the left coronary artery. At this dose, verapamil did not affect atrioventricular conduction.

Adult↗

PubMed1997

The value of emergency CT studies in spontaneous rupture of hepatocellular carcinoma. Analysis for tumor protrusion and hemorrhagic ascites.

CT characteristics of spontaneous rupture of HCC (n = 13) were reviewed retrospectively, and the value of emergency CT studies in this disease was evaluated. Especially, tumor protrusion ratio (TPR) and ascitic CT numbers were measured to for comparison with the data for unruptured HCCs and ordinary (e.g. non hemorrhagic) ascites (n = 13). As a result, except for diffuse type HCCs, the TPR was significantly higher than for the unruptured HCCs. Nine cases had intraperitoneal HDAs, and the laterality of the HDAs corresponded with that of the ruptured tumors in 8 cases. Also, the ascitic CT numbers apart from the HDA were still higher than the ordinary ascites. Therefore, a high TPR, HDAs adjacent to the tumor, and elevated ascitic CT numbers are important CT manifestations indicating HCC rupture. Diffuse HCCs, however, require careful clinical evaluation.

Adult↗