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Biomedical subjects

M Shiota

Publications and source records attributed to M Shiota.

At least 37 records · Page 2Linked to original sources
PubMed2000

Tumor necrosis factor alpha 5'-flanking region, tumor necrosis factor receptor II, and HLA-DRB1 polymorphisms in Japanese patients with rheumatoid arthritis.

OBJECTIVE: New polymorphisms affecting transcriptional activity were recently reported within the 5'-flanking region of the tumor necrosis factor alpha gene (TNFalpha). In addition, genome-wide linkage screening indicated 1p36 as one of the candidate chromosomal regions where the TNF receptor II gene (TNFR2) is located. In the present study, HLA-DRB1, TNFalpha promoter, and TNFR2 genotypes were determined to examine whether these polymorphisms are associated with rheumatoid arthritis (RA), either independently or in combination. METHODS: Genotypes of HLA-DRB1, TNFalpha upstream promoter, and TNFR2 codon 196 were determined in 545 Japanese patients with RA and 265 healthy controls. Association of these genes with susceptibility to RA was analyzed both independently and after stratification by one of the genotypes. RESULTS: As expected, the HLA-DRB1 shared epitope was strongly associated with RA. In addition, a significant negative association of DRB1*1405 and 1302 was observed. Furthermore, DRB1*1405 was suggested to possess a protective role for the development of RA in DRB1*0405-positive individuals. A significant increase in TNFalpha-U02 in RA was detected, which was not independent of DRB1*0405. A significant association was not observed between TNFR2-196M/R polymorphism and RA. CONCLUSION: Among the 3 genes examined in this study, HLA-DRB1 was considered to be most strongly associated with RA.

Antigens, CD↗
PubMed2000

Cognitive and neurophysiological evaluation of Japanese dyslexia.

Seven Japanese dyslexic boys were evaluated as to their pedagogic performance on the pupil rating scale (PRS), and psychological and neurophysiological characteristics. One of them suffered from severe English dyslexia despite that his Japanese dyslexia was feeble. PRS did not successfully reveal their reading difficulties. Psychological examination (WISC-R and K-ABC) revealed their cognitive dysfunction, but the results were heterogeneous. The Token test was most useful for detecting their poor reading comprehension. Electroencephalogram (EEG) coherence analysis showed high inter- and intra-hemispheric values. These findings may imply hyperconnectivity of the cerebral white matter in dyslexia. We assumed that the Token test demonstrates the discrepancy between reading and hearing comprehension best of all among these psychological tests and that connectivity between non-functional cortical lesions remains in dyslexic children.

Adolescent↗
PubMed2000

Mast cell tryptase from pig lungs triggers infection by pneumotropic Sendai and influenza A viruses. Purification and characterization.

A novel trypsin-type serine proteinase, which processes the precursors of the envelope fusion glycoproteins of pneumotropic Sendai and human influenza A viruses, was purified to homogeneity from pig lungs. On SDS/PAGE, the purified enzyme gave a protein band corresponding to about 32 kDa, and has an apparent molecular mass of 120 kDa, as determined by gel permeation chromatography. Immunohistochemical staining with antibodies against this enzyme revealed that the enzyme is located in pig lung mast cells. The N-terminal 44-amino-acid sequence of the enzyme exhibits about 80% identity with those of mast cell tryptases from other species. Of the inhibitors tested, di-isopropyl fluorophosphate, antipain, leupeptin, benzamidine and a few proteinaceous inhibitors, such as mucus protease inhibitor and aprotinin, inhibited this enzyme activity. Heparin stabilized the enzyme, but high-ionic-strength conditions did not, unlike for human mast cell tryptase. The purified enzyme efficiently processed the fusion glycoprotein precursor of Sendai virus and slowly processed hemagglutinin of human influenza A virus, and triggered the infectivity of Sendai virus in a dose-dependent manner, although human mast cell tryptase beta and rat mast cell tryptase (rat MCP-7) from lungs did not process these fusion glycoproteins at all. These results suggest that mast cell tryptase in pig lungs is the possible trigger of the pneumotropic virus infections.

Amino Acid Sequence↗
PubMed2000

Phosphoenolpyruvate carboxykinase is necessary for the integration of hepatic energy metabolism.

We used an allelogenic Cre/loxP gene targeting strategy in mice to determine the role of cytosolic phosphoenolpyruvate carboxykinase (PEPCK) in hepatic energy metabolism. Mice that lack this enzyme die within 3 days of birth, while mice with at least a 90% global reduction of PEPCK, or a liver-specific knockout of PEPCK, are viable. Surprisingly, in both cases these animals remain euglycemic after a 24-h fast. However, mice without hepatic PEPCK develop hepatic steatosis after fasting despite up-regulation of a variety of genes encoding free fatty acid-oxidizing enzymes. Also, marked alterations in the expression of hepatic genes involved in energy metabolism occur in the absence of any changes in plasma hormone concentrations. Given that a ninefold elevation of the hepatic malate concentration occurs in the liver-specific PEPCK knockout mice, we suggest that one or more intermediary metabolites may directly regulate expression of the affected genes. Thus, hepatic PEPCK may function more as an integrator of hepatic energy metabolism than as a determinant of gluconeogenesis.

Alleles↗
PubMed2000

Combined intraportal infusion of acetylcholine and adrenergic blockers augments net hepatic glucose uptake.

Portal glucose delivery in the conscious dog augments net hepatic glucose uptake (NHGU). To investigate the possible role of altered autonomic nervous activity in the effect of portal glucose delivery, the effects of adrenergic blockade and acetylcholine (ACh) on hepatic glucose metabolism were examined in 42-h-fasted conscious dogs. Each study consisted of an equilibration (-120 to -20 min), a control (-20 to 0 min), and a hyperglycemic-hyperinsulinemic period (0 to 300 min). During the last period, somatostatin (0.8 microg. kg(-1). min(-1)) was infused along with intraportal insulin (1.2 mU. kg(-1). min(-1)) and glucagon (0.5 ng. kg(-1). min(-1)). Hepatic sinusoidal insulin was four times basal (73 +/- 7 microU/ml) and glucagon was basal (55 +/- 7 pg/ml). Glucose was infused peripherally (0-300 min) to create hyperglycemia (220 mg/dl). In test protocol, phentolamine and propranolol were infused intraportally at 0.2 microg and 0.1 microg. kg(-1). min(-1) from 120 min on. ACh was infused intraportally at 3 microg. kg(-1). min(-1) from 210 min on. In control protocol, saline was given in place of the blockers and ACh. Hyperglycemia-hyperinsulinemia switched the net hepatic glucose balance (mg. kg(-1). min(-1)) from output (2.1 +/- 0.3 and 1.1 +/- 0.2) to uptake (2.8 +/- 0.9 and 2.6 +/- 0.6) and lactate balance (micromol. kg(-1). min(-1)) from uptake (7.5 +/- 2.2 and 6.7 +/- 1.6) to output (3.7 +/- 2.6 and 3.9 +/- 1.6) by 120 min in the control and test protocols, respectively. Thereafter, in the control protocol, NHGU tended to increase slightly (3.0 +/- 0.6 mg. kg(-1). min(-1) by 300 min). In the test protocol, adrenergic blockade did not alter NHGU, but ACh infusion increased it to 4.4 +/- 0.6 and 4.6 +/- 0.6 mg. kg(-1). min(-1) by 220 and 300 min, respectively. These data are consistent with the hypothesis that alterations in nerve activity contribute to the increase in NHGU seen after portal glucose delivery.

Acetylcholine↗
PubMed2000

[Clinical study on risk management for dental implant treatment--Part 1. Clinical retrospective study on the medically compromised patients at clinic for oral implant].

A retrospective study on medically compromised patients was made using 1,000 outpatients who visited the Clinic for Oral Implant, University Hospital, Faculty of Dentistry, Tokyo Medical and Dental University between April 1995 and June 1998. The results were as follows: 1. 35.3% (353 patients: 140 males and 213 females) of the outpatients were medically compromised. 2. The greatest number of medically compromised patients was in the 50-59 age group (118 cases), followed by those in the 40-49 and 60-69 age groups. 3. The highest ratio of medically compromised patients was in the 60-69 age group (48.2%), followed by those in the 70-79 and 50-59 age groups. 4. Among the 353 patients, 96 (27.2%) underwent surgical treatment such as insertion of implant (68 cases), removal of implant, extraction of tooth, and free gingival graft. 5. Among the 68 patients who underwent insertion of implant, in a classification by type of disease, the patients with cardiovascular diseases were the most numerous (33.9%), followed by metabolic and digestive tract diseases. 6. All surgical treatments of implant insertion were performed under local anesthesia, while monitoring cardiac and respiratory function, and SpO2. Among the 68 patients, 9 underwent operation under intravenous sedation and 2 under nitrous oxide inhalation sedation. All 11 patients had hypertension. The results suggested that identification of preoperative risk factors, precise recognition of general condition, and establishment of control system are important to manage medically compromised patients for dental implant treatment.

Adult↗
PubMed2000

[Distribution in normal subjects of performance in Token test: a basic study for the diagnosis of learning disabilities].

For the diagnosis of specific reading disorder (SRD) we studied the distribution in 187 elementary school children of the scores of Token test. Token test was performed under two conditions: listening and reading by presenting the same sentences. The diagnosis required a normal score under the listening condition, an abnormally low score under the reading condition and significantly large discrepancy between them. This test is valid and convenient for the diagnosis of SRD.

Acoustic Stimulation↗
PubMed2000

[A patient with recurrent uterine cervical cancer successfully treated by combined modality therapy including local injection of anticancer agents based on CDDP].

The patient was a 77-year-old woman who had undergone total abdominal hysterectomy and bilateral salpingo-oophorectomy following the diagnosis of uterine cervical cancer at the age of 57. A recurrent tumor was detected on the anterior surface of the right iliopsoas muscle and fine needle aspiration of the tumor revealed squamous cell carcinoma. A needle was inserted into the tumor under transabdominal ultrasound guidance, and anticancer agents, chiefly cis-diamminedichloroplatinum [II] (CDDP), were injected. The patient also received systemic chemotherapy (CAP therapy) and radiotherapy. Subsequently, computed tomography showed a 73% reduction in the size of the tumor. A mass 7 cm in diameter was still present on the anterior surface of the iliopsoas after treatment, but tumor markers fell to normal levels. The patient is presently receiving UFT (600 mg/day) as maintenance therapy. At 48 months after recurrence, there has been no increase in the tumor size or tumor marker levels, and the performance status is grade 0. In conclusion, a good outcome was achieved by local injection of anticancer agents combined with systemic chemotherapy and radiotherapy, and there were few side effects.

Aged↗
PubMed1999

Dual roles for glucokinase in glucose homeostasis as determined by liver and pancreatic beta cell-specific gene knock-outs using Cre recombinase.

Glucokinase (GK) gene mutations cause diabetes mellitus in both humans and mouse models, but the pathophysiological basis is only partially defined. We have used cre-loxP technology in combination with gene targeting to perform global, beta cell-, and hepatocyte-specific gene knock-outs of this enzyme in mice. Gene targeting was used to create a triple-loxed gk allele, which was converted by partial or total Cre-mediated recombination to a conditional allele lacking neomycin resistance, or to a null allele, respectively. beta cell- and hepatocyte-specific expression of Cre was achieved using transgenes that contain either insulin or albumin promoter/enhancer sequences. By intercrossing the transgenic mice that express Cre in a cell-specific manner with mice containing a conditional gk allele, we obtained animals with either a beta cell or hepatocyte-specific knock-out of GK. Animals either globally deficient in GK, or lacking GK just in beta cells, die within a few days of birth from severe diabetes. Mice that are heterozygous null for GK, either globally or just in the beta cell, survive but are moderately hyperglycemic. Mice that lack GK only in the liver are only mildly hyperglycemic but display pronounced defects in both glycogen synthesis and glucose turnover rates during a hyperglycemic clamp. Interestingly, hepatic GK knock-out mice also have impaired insulin secretion in response to glucose. These studies indicate that deficiencies in both beta cell and hepatic GK contribute to the hyperglycemia of MODY-2.

Albumins↗
PubMed1999

Mice lacking alpha-calcitonin gene-related peptide exhibit normal cardiovascular regulation and neuromuscular development.

alpha-Calcitonin gene-related peptide (alphaCGRP) is a pleiotropic peptide neuromodulator that is widely expressed throughout the Central and peripheral nervous systems. CGRP has been implicated in a variety of physiological processes including peripheral vasodilation, cardiac acceleration nicotinic acetylcholine receptor (AChR) synthesis and function, testicular descent, nociception, carbohydrate metabolism, gastrointestinal motility, neurogenic inflammation, and gastric acid secretion. To provide a better understanding of the physiological role(s) mediated by this peptide neurotransmitter, we have generated alphaCGRP-null mice by targeted modification in embryonic stem cells. Mice lacking alpha CGRP expression demonstrate no obvious phenotypic differences from their wild-type littermates. Detailed analysis of systemic cardiovascular function revealed no differences between control and mutant mice regarding heart rate and blood pressure under basal or exercise-induced conditions and subsequent to pharmacological manipulation. Characterization of neuromuscular junction in morphology including nicotinic receptor localization, terminal sprouting in response to denervation, developmental regulation of AChR subunit expression, and synapse elimination also revealed no differences in alphaCGRP-deficient animals. These results suggest that alphaCGRP is not required for the systemic regulation of cardiovascular hemodynamics or development of the neuromuscular junction.

Aging↗
PubMed1999

Identification of the gene variations in human CD22.

CD22, a member of the immunoglobulin superfamily, is a B-cell transmembrane glycoprotein that acts as an accessory-signaling component of the B-cell antigen receptor (BCR). Recent evidence indicating the role of CD22 as a negative regulator of BCR signal transduction prompted us to test the possibility that genetic variations of human CD22 may be associated with autoimmune diseases. In this study, variation screening of the entire CD22 coding region was performed, and possible association with rheumatic diseases was tested, using the genomic DNA from 207 healthy Japanese individuals, 68 patients with systemic lupus erythematosus (SLE), and 119 patients with rheumatoid arthritis (RA). Through the variation screening, seven non-synonymous and four synonymous substitutions were identified. In addition, single base substitutions were found in two introns flanking exon-intron junctions. Among these variations, Q152E substitution within the second extracellular domain was observed with a marginally higher frequency in the patients with SLE (3/68, 4.4%) than that in healthy individuals (1/207, 0.5%) (P=0.048. SLE vs healthy individuals), although this difference was no longer significant after correction for the number of comparisons (Pc=0.62). No significant association was observed between any of the variations and RA. These findings indicate that a number of genetic variants are present in CD22, and suggest that CD22 could be considered a candidate for the susceptibility genes to autoimmune diseases.

Adolescent↗
PubMed1999

The role of the Epstein-Barr virus in the oncogenesis of EBV(+) gastric carcinomas.

Five hundred and thirteen cases of gastric carcinoma were investigated for the presence of viral RNA, and the clinico-pathological data, geno-type, BamHIF restriction fragment polymorphism (RFLP) and specific LMP-1 30 bp gene deletion were also examined. EBVs detected in lymphocytes in 20 normal gastric mucosa, 7 lymphoma cell lines (LCLs) maintained in severe combined immunodeficiency (SCID) mice and 18 non-Hodgkin's lymphomas were compared with those in the gastric carcinoma cases. Thirty-three cases (6.4%) were demonstrated to be positive for EBV by means of EBER-1 RNA in situ hybridization. Clinico-pathological data showed no statistically significant difference in histological grading, location of cancer and status of vessel and lymphatic invasion between the EBV-positive and -negative groups, although the former significantly predominated in the submucosal invasion group (submucosal vs mucosal P=0.021; submucosal vs advanced cancer P=0.033). Some of these data were different from corresponding data in earlier reports. In cases that were evaluated by molecular biology, type A, wild-type F and LMP-1 gene deletion predominated except one in 21 informative cases, one in 24 and two in 16, respectively. EBVs detected in lymphocytes in normal gastric mucosa, LCLs in SCID mice and non-Hodgkin's lymphoma were also predominantly affected by type A, wild-type F and LMP-1 gene deletion with few exceptions. The results indicate a lack of genetic differences among EBVs in gastric carcinoma, normal population, LCLs of SCID mice and non-Hodgkin lymphomas. Some EBV infections in gastric carcinomas may be transient, especially in the submucosal invasion group.

Animals↗
PubMed1999

Allele typing of human TNFA 5'-flanking region using polymerase chain reaction-preferential homoduplex formation assay (PCR-PHFA): linkage disequilibrium with HLA class I and class II genes in Japanese.

Tumor necrosis factor alpha plays a substantial role in a number of conditions such as inflammation, autoimmunity, insulin resistance and sleep. Three new single nucleotide polymorphisms, -1,031 T/C, -863 C/A and -857 T/C, were recently identified in the upstream 5'-flanking region of TNFA in the Japanese population. In the present study, we developed polymerase chain reaction (PCR)-preferential homoduplex formation assay for the single-step allele typing of TNFA, and determined the genotypes of 271 healthy unrelated Japanese individuals. Four haplotypes, -1,031/-863/-857 TCC, TCT, CAC and CCC, were found to constitute the majority, if not all, of the TNFA alleles of healthy Japanese population. These alleles were designated as TNFA-U01, -U02 -U03 and -U04, respectively, in the order of frequency. Based on HLA-A, -B and -DRB1 genotypes together with TNFA genotypes, multi-locus haplotypes were analyzed. Significant positive associations were observed between TNFA-U01 and A*3303, B*5201, B*4403, B*4601, B*0702, DRB1*1502, DRB1*0101, DRB1*1302, between TNFA-U02 and B*5401, B*3501, DRB1*0405, DRB1*0407, between TNFA-U03 and B*4006, B*4002, DRB1*0803, DRB1*0802, DRB1*0403, DRB1*0901, and between TNFA-U04 and B*4801. Four-locus haplotype estimation revealed that A*3303-B*4403-TNFA-U01-DRB1*1302, A*2402-B*5201-TNFA-U01-DRB1*1502 and A*2402-B*5401-TNFA-U02-DRB1*0405 constitute major extended haplotypes in Japanese. Interestingly, TNFA alleles previously shown to have a higher promoter activity (U02, U03) were found to form haplotypes with certain DRB1 alleles associated with T helper 1 (Th1)-dominant diseases such as rheumatoid arthritis, insulin dependent diabetes mellitus and Crohn's disease in Japanese. In contrast, TNFA allele with a low promoter activity (U01) is in linkage disequilibrium with the DRB1 alleles associated with T helper 2 (Th2)-dominant diseases such as atopic dermatitis and ulcerative colitis. These observations raise the possibility that TNFA upstream promoter region polymorphisms contribute to some of the HLA-disease associations.

5' Untranslated Regions↗
PubMed1999

Lack of a strong association of CTLA-4 exon 1 polymorphism with the susceptibility to rheumatoid arthritis and systemic lupus erythematosus in Japanese: an association study using a novel variation screening method.

CTLA-4 is considered to be one of the attractive candidates for the susceptibility genes to rheumatic diseases. In the present study, the association of CTLA-4 polymorphism with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) was examined in the Japanese population using the case-control association analysis. Polymerase chain reaction-preferential homoduplex formation assay (PCR-PHFA) was applied for the screening of genetic variations and for the genotyping of a large number of samples. A greater proportion of Japanese patients with RA (44%) and SLE (44%) compared with healthy individuals (37%) had exon 1 49 G/G genotype, but the difference did not reach statistical significance. However, when the patients with RA and healthy individuals were stratified according to HLA-DRB1 alleles, a weakly significant increase of the positivity of CTLA-4 49G allele was observed in HLA-DRB1*0405-positive patients (87%) compared with DRB1*0405-positive healthy individuals (71%) (P = 0.014, odds ratio = 2.77). These results indicate that CTLA-4 exon 1 polymorphism does not contribute greatly to the susceptibility to RA and SLE, at least in Japanese, although the presence of CTLA4 49G allele could be a minor predisposing factor for RA in HLA-DRB1*0405-positive individuals. In addition, PCR-PHFA was shown to be useful for a mass screening of gene variations.

Abatacept↗
PubMed1999

Oxidative stability of fish oil blended with butter.

The oxidative stability of fish oil blended with milk products was evaluated. Oxidation of the oil blend was determined by peroxide value and rancimat test. Improved oxidative stability was observed for fish oil blended with butter. Unsalted and salted butters showed no difference in improvement of effect on oxidative stability of fish oil. No influence on oxidative stability for the fish oil was observed with butter oil, which was the oil fraction of butter. These studies suggested that the improved oxidative stability of fish oil-butter blend was due to the hydrophilic fraction of butter and that butter could improve the oxidative stability of polyunsaturated oils such as fish oil.

Antioxidants↗
PubMed1999

[Clinical retrospective study on outpatients at clinic for oral implant].

A retrospective study was made on 1,000 outpatients visiting the Clinic for Oral Implant, University Hospital, Faculty of Dentistry, Tokyo Medical and Dental University between April 1995 and June 1998. The following findings were obtained according to sex, age group, reason for visit, classification of edentulous area, indication and contraindication for implant therapy, and pre-implant surgical treatment. Forty percent of the outpatients were male and 60% were female. The largest number was in the 50-59-year-old group. The reason for visit of 822 patients was request for implant therapy. 123 patients with uncomfortable implants done at other clinics, 12 patients undergoing maintenance of implants at other clinics and 43 other patients. There were 505 upper jaw cases and 529 lower jaw cases. Most anterior edentulous cases were in the upper jaw group. Most of the posterior edentulous cases were unilateral cases and many of them were free-end saddle cases. Indication patients were 447 of the 822 outpatients. The main contraindication was insufficient volume of bone. Two hundred twenty-one of the 477 indication patients did not need the pretreatment which consisted of extraction, bone graft, free gingival graft, provisional prosthetics, sinus lift, and so on.

Adult↗