Search PubMed⌕ Search

Biomedical subjects

N Tsuchiya

Publications and source records attributed to N Tsuchiya.

At least 91 records · Page 5Linked to original sources
PubMed1999

[Prolonged antinociceptive effect of poly (DL-lactic acid)-fentanyl composites after their intrathecal injection in rats].

We synthesized poly (DL-lactic acid)-fentanyl composites and compared the duration of analgesia after the administration of a single intrathecal dose of these agents in rats. The drug was injected with an intrathecal catheter into the intrathecal space. Fentanyl composites or plain fentanyl in doses of 2.5 or 25 micrograms were administered, respectively. Animals were then tested for analgesia using the tail-flick test. The release rate of fentanyl from fentanyl composites in vitro was also evaluated. The antinociceptive effect of fentanyl composites (25 micrograms) was significantly longer than that of plain fentanyl. Administration of poly (DL-lactic acid) alone did not induce the antinociceptive effect. Four of 7 animals given plain fentanyl (25 micrograms) exhibited temporary respiratory depression, but none of the animals given fentanyl composites showed this response. In vitro experiments demonstrated a slow release of fentanyl from the fentanyl composites. We conclude that the antinociceptive effect of fentanyl can be prolonged when administered as a poly (DL-lactic acid)-fentanyl composite in the intrathecal space with decreased systemic side effects compared with the plain formulation.

Analgesics, Opioid↗
PubMed1999

HLA-B27 subtypes and HLA class II alleles in Japanese patients with anterior uveitis.

PURPOSE: Some patients with anterior uveitis (AU) have ankylosing spondylitis (AS) and are HLA-B27 class I-positive. The purpose of this study was to investigate whether there are differences in HLA at the allele level among each group of patients with AU. METHODS: Seventy-three patients with AU were studied. They were classified into three groups: 31 with AS-associated AU, 14 with HLA-B27-associated AU, and 28 with idiopathic AU. Three control groups without AU were used: 138 random subjects, 33 HLA-B27-positive healthy subjects, and 19 HLA-B27-positive patients with AS. DRB1 and DQB1 genotyping was performed using polymerase chain reaction (PCR)-single-strand conformation polymorphism (PCR-SSCP) and PCR-restriction fragment length polymorphism. HLA-B27 subtype was determined by PCR-SSCP. RESULTS: There was no difference in the frequency of any class I antigen except HLA-B27 among the patients studied. The frequencies of HLA-DR12 in AS-associated AU and HLA-DR1 in HLA-B27-associated AU showed an increase. In HLA-B27-associated AU, DRB1*0101 and DQB1*0501 were increased compared with HLA-B27-positive control subjects. When HLA-B27 subtype distribution was compared among the groups, the proportion of B*2704 was significantly lower in HLA-B27-associated AU (P = 0.037), however, such a difference was not present in AS-associated groups. CONCLUSIONS: These results indicated that B*2704 seemed to be less susceptible to AU compared with B*2705 in Japanese subjects. The increase of HLA-DR12 and HLA-DR1 in AU may be caused by linkage disequilibrium with B*2704 and B*2705, respectively.

Adult↗
PubMed1999

The effects of fabric air permeability and moisture absorption on clothing microclimate and subjective sensation in sedentary women at cyclic changes of ambient temperatures from 27 degrees C to 33 degrees C.

The present paper aimed at learning the effects of two different levels of air permeability and moisture absorption on clothing microclimate and subjective sensation in sedentary women. Three kinds of clothing ensemble were investigated: 1) polyester clothing with low moisture absorption and low air permeability (A clothing); 2) polyester clothing with low moisture absorption and high air permeability (B clothing); and 3) cotton clothing with high moisture absorption and high air permeability (C clothing). After 20 min of dressing time, the room temperature and humidity began to rise from 27 degrees C and 50% rh to 33 degrees C and 70% rh over 20 min, and it was maintained for 30 min (Section I); it then began to fall to 27 degrees C and 50% rh over 20 min, and it was maintained there for 20 min (Section II). The subject sat quietly on a chair for 110 min. The main findings are summarized as follows: 1) The clothing surface temperature was significantly higher in C clothing than in B clothing during section I, but it was significantly higher in B clothing than in C clothing during section II. 2) Although the positive relationship between the microclimate humidity and forearm sweat rate was significantly confirmed in all three kinds of clothing, the microclimate humidity at the chest for the same sweat rate was lower in C clothing than in A and B clothing. These results were discussed in terms of thermal physiology.

Adult↗
PubMed1998

Age-associated changes in mitochondrial mRNA expression and translation in the Wistar rat heart.

The purpose of this research is to determine possible causes and mechanisms involved in the age-associated decline in mitochondrial activity. We have focused on cytochrome c oxidase because it is comprised of both nuclear and mitochondrial-encoded subunits and may provide some insight into the coordination of the two genomes. In agreement with previous reports, we show an approximate 30% decrease in cardiac cytochrome c oxidase activity at 24 months compared to 6 months with no change in the activity of the nuclear encoded citrate synthase of the mitochondrial matrix. The rate of the mitochondrial protein synthesis as shown by [35S]methionine incorporation decreased approximately 35% in the 24-month-old rat compared to the 6-month-old rat. The decrease in protein synthesis was associated with a 30-50% reduction in the levels of most individually radiolabeled translation products including the COX subunits and specifically, a 23% decrease in COX1 protein steady-state levels according to Western analysis. Similarly, there was a decrease in the mRNA steady-state levels of both nuclear and mitochondrial-encoded subunits of cytochrome c oxidase. These results suggest that a number of different mechanisms are involved in the age-associated decrease in heart mitochondrial activity and these are discussed.

Aging↗
PubMed1998

MICA allele typing of HLA-B27 positive Japanese patients with seronegative spondylarthropathies and healthy individuals: differential linkage disequilibrium with HLA-B27 subtypes.

OBJECTIVE: To examine whether MICA (major histocompatibility complex [MHC] class I-related chain gene A) confers additional susceptibility for seronegative spondylarthropathies in HLA-B27 positive Japanese individuals. METHODS: A polymerase chain reaction-single-strand conformation polymorphism method was developed, and the MICA alleles of 18 Japanese patients with ankylosing spondylitis, 1 patient with Reiter's syndrome, and 17 healthy HLA-B27 positive Japanese subjects were determined. RESULTS: Among 26 individuals with HLA-B*2704 (13 patients and 13 healthy subjects), all except 1 healthy individual were positive for MICA010, whereas all 9 HLA-B*2705 positive subjects (6 patients and 3 healthy subjects) possessed MICA007. One healthy individual with HLA-B*2711 also carried MICA010. CONCLUSION: Strong linkage disequilibrium is present between HLA-B*2704 and MICA010, as well as between HLA-B*2705 and MICA007. Although HLA-B*2704 and B*2705 are highly homologous, each subtype participates in a different MHC haplotype. Direct involvement of MICA polymorphism in the pathogenesis seems to be unlikely; however, such information will provide a useful tool for elucidating the evolutional pathway of HLA-B27 subtypes as well as the contribution of other genes within the MHC region in the pathogenesis of these diseases.

Alleles↗
PubMed1998

Nahocols and isonahocols, endothelin antagonists from the brown alga, Sargassum autumnale.

Novel endothelin antagonists, nahocols A, A1, B, C, D1 and D2, and isonahocols D1 and D2, were isolated from the brown alga, Sargassum autumnale. Their structures were determined through detailed analysis of NMR spectra and chemical reactions. Nahocols have an aryl prenyl ether structure, which are speculated to be biogenetic precursors of the ubiquitous prenyl hydroquinones or prenyl benzoquinones in the plant and animal kingdoms.

Endothelin-1↗
PubMed1998

Cytotoxic scalarane sesterterpenes from a sponge, Hyrtios erecta.

Novel scalarane sesterterpenes (1-4) were isolated from a sponge, Hyrtios erecta (order Dictyoceratida). They were characterized by means of spectral analyses, X-ray crystallography, and chemical reactions. Compound 1 showed potent in vitro and in vivo antitumor activities. In addition, the structure-activity relationship was also discussed using computer-assisted structure matching of 1 and aragusterols.

Animals↗
PubMed1998

Cloning and characterization of a cDNA encoding a novel heterogeneous nuclear ribonucleoprotein-like protein and its expression in myeloid leukemia cells.

We isolated a cDNA encoding a novel heterogeneous nuclear ribonucleoprotein (hnRNP)-like protein on DNA affinity screening of a K562 cDNA expression library with an oligodeoxynucleotide (JKT41) derived from intron 9 of the human myeloperoxidase gene. The cDNA has a 1,305 bp sequence that encodes a polypeptide of 301 amino acid residues. The protein, named JKTBP, contains two repeats of a putative RNA binding domain (RBD), each composed of canonical RNP-2 and RNP-1 motifs, and a glycine- and tyrosine-rich carboxyl terminus. The sequences of these two repeats are highly homologous with those of the 2 x RBD-Gly rich group of hnRNPs. Northern blotting showed that two mRNAs of approximately 1.4 and 2.8 kb were present in most cultured cells examined. The recombinant protein expressed in Escherichia coli interacted with the double-stranded form of JKT41 as well as with its single-stranded form. This interaction was competitively inhibited by the same unlabeled JKT41 and to nearly the same extent by unrelated oligonucleotides. Moreover, the recombinant protein interacted with poly(G) and poly(A), but not with poly(U) or poly(C). Transient expression of the protein in SKM-1 cells repressed the expression of chloramphenicol acetyltransferase reporter genes located downstream of the intron 9 element of JKT41 or intron 7 element of FERE27. The implications of the protein in the biogenesis of mRNA are discussed.

Amino Acid Sequence↗
PubMed1998

Xanthan lyase of Bacillus sp. strain GL1 liberates pyruvylated mannose from xanthan side chains.

When the bacterium Bacillus sp. strain GL1 was grown in a medium containing xanthan as the carbon source, the viscosity of the medium decreased in association with growth, showing that the bacterium had xanthan-depolymerizing enzymes. One of the xanthan-depolymerizing enzymes (xanthan lyase) was present in the medium and was found to be induced by xanthan. The xanthan lyase purified from the culture fluid was a monomer with a molecular mass of 75 kDa, and was most active at pH 5.5 and 50 degrees C. The enzyme was highly specific for xanthan and produced pyruvylated mannose. The result indicates that the enzyme cleaved the linkage between the terminal pyruvylated mannosyl and glucuronyl residues in the side chain of xanthan.

Bacillus↗
PubMed1998

Association of HLA class I and class II alleles with myositis in Japanese patients.

OBJECTIVE: To investigate the correlation of HLA class I and class II antigens and alleles with various forms of myositis in Japanese patients. METHODS: Eighty-four Japanese patients with myositis [22 with polymyositis (PM), 46 with dermatomyositis (DM), 16 with myositis overlapping with other collagen vascular diseases] were typed serologically for HLA-A, B, C antigens. HLA-DRB1, DQA1, and DQB1 alleles were determined by polymerase chain reaction dependent DNA typing methods. Fifty-eight Japanese controls were typed serologically while HLA-DRB1, DQA1, and DQB1 allele typing was carried out in 175, 95, and 104 controls, respectively. RESULTS: HLA-B7 was higher in patients than controls [20.2 vs 6.9% in controls: p=0.02, odds ratio (OR)=3.4]. The increase of HLA-B7 was largely dependent on the increase in overlap patients (37.5%; p=0.005, OR=8.1). HLA-A24 and B52 were significantly decreased in PM as compared to DM, while CW3 was significantly increased in PM versus DM. DRB1*08 alleles were significantly increased in patients (36.9 vs 20.5% in controls; p=0.004, OR=2.3), especially in PM and DM. DQA1*0501 and DQB1*0301 were significantly decreased in patients [4.8 vs 13.7% in controls; p=0.04, OR=0.32, and 8.3 vs 20.2% in controls; p=0.02, OR=0.36, respectively]. CONCLUSION: HLA-class I and class II alleles associated with Japanese patients with myositis may be different from those associated with Caucasian patients.

Alleles↗
PubMed1997

Induction of alternative splicing of HLA-B27 by bacterial invasion.

OBJECTIVE: Alternative splicing of certain class I major histocompatibility complex pre-messenger RNA (pre-mRNA) is known to lead to generation of a cell-free soluble protein analog. This study was undertaken to examine whether this process occurs with HLA-B27, whether the process is modified by arthritis-causing bacteria, and whether the assembly of the soluble molecules follows the same pathway as the integral parent molecules. METHODS: Alternative splicing of pre-mRNA was analyzed by reverse transcriptase-polymerase chain reaction, and assembly of soluble HLA-B27 by immunoprecipitation followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. RESULTS: There was alternative splicing of the pre-mRNA of HLA-B27. The process could be amplified by invasion with Salmonella or Yersinia bacteria. The soluble HLA-B27 was assembled in a pathway similar to that of the parent molecule. CONCLUSION: The association between arthritis-causing bacteria and HLA-B27 positive cells is a complex event. Soluble HLA-B27 is a potential key player.

Alternative Splicing↗
PubMed1997

Genomic organization of the OS-9 gene amplified in human sarcomas.

The OS-9 gene is frequently amplified in human sarcomas. We isolated and characterized an OS-9 genomic DNA from a human BAC library. Sequencing of the genomic DNA showed that the gene spanned approximately 30.4 kbp and had 15 exons. The 1,010 bp sequence of the 5' upstream region was also determined. The potential binding-sequence motifs TATA and CCAAT for general transcription factors were found in the 5' upstream region. Primer extension analysis revealed two putative transcription start sites. The significance of the 5' upstream sequence in the ubiquitous expression of the OS-9 gene in various tissues and culture cells is discussed.

Base Sequence↗
PubMed1997

Mitochondrial biogenesis during cellular differentiation.

Mitochondrial biogenesis was studied during differentiation of two immortalized cell lines (C2C12, 3T3) with enzyme measurements, Northern blots, and quantitative ultrastructure. Citrate synthase, isocitrate dehydrogenase, and 3-hydroxyacyl-CoA dehydrogenase (nuclear encoded, mitochondrial matrix location) showed linear, four- to sixfold increases in enzymatic activity in C2C12 cells but increased exponentially in 3T3 cells. Cytochrome oxidase and NADH dehydrogenase (nuclear and mitochondrial encoded, cristae location) increased to a lesser extent and with a pattern dissimilar to the first group. Northern blots and activity of succinate dehydrogenase (cristae location but entirely nuclear encoded) suggested the groupings were based on location of the genes rather than the mature enzyme. However, quantitative electron microscopy and comparisons with adult tissue suggested that mitochondrial ultrastructure can influence the change in cristae enzymes. Cristae surface area per unit mitochondrial volume and per unit cell volume increased much less than did cristae enzymes. Available space on the inner membrane may become limiting and account for some aspects of the pattern of change in electron transport enzymes during differentiation.

3T3 Cells↗
PubMed1997

Angiotensin-converting enzyme gene polymorphism and cardiovascular endocrine system in coronary angiography patients.

There is continuing interest in the link between angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism and cardiovascular diseases. Studies on various ethnic populations have shown conflicting evidence as to the association of the DD genotype with an increased risk of myocardial infarction. We examined the relationship between various cardiovascular hormones and ACE gene polymorphism in 149 subjects who underwent cardiac catheterization and had normal cardiac function. The distribution of the II, ID, and DD genotypes was 68, 67, and 14, respectively. Although serum ACE activity was higher in DD and ID than in II (II 9.7+/-0.5 IU/l, ID 12.2+/-0.5, DD 12.8+/-1.2; p < 0.005), other factors of the renin-angiotensin system such as plasma renin activity and plasma concentrations of angiotensin II and aldosterone were not different among the three genotypes. Plasma catecholamines did not differ among the ACE genotypes either, however, plasma atrial natriuretic peptide (ANP) was significantly lower in the subjects carrying the D allele (II 38+/-5 pg/ml, ID 26+/-2, DD 21+/-3; p < 0.05). In particular, the DD genotype showed a low plasma ANP level although the left ventricular mass index was greater than the other genotypes (II 133+/-5 g/m2, ID 137+/-6, DD 165+/-7; p < 0.05). The low plasma ANP in the DD genotype may contribute to the increased risk of cardiovascular diseases.

Atrial Natriuretic Factor↗
PubMed1997

[Long-term beneficial effect of dual chamber pacing in a patient with hypertrophic obstructive cardiomyopathy].

Dual chamber (DDD) pacing therapy was effective to reduce the left ventricular outflow tract pressure gradient for a long time in a patient with pharmacotherapy-resistant hypertrophic obstructive cardiomyopathy. A 52-year-old man with pharmacotherapy-resistant pressure gradient was treated by a DDD pacemaker implantation, because the pressure gradient was proved to be reduced (94-->16 mmHg) by transient DDD pacing with an atrioventricular delay of 50 msec. Hemodynamics and ventricular wall thickness were serially observed after the implantation for 2 years. The pressure gradient progressively decreased during the pacing period, at 4 months and 2 years follow-up, (10-->2 mmHg) and during the sinus rhythm period (60-->25 mmHg), and left ventricular ejection fraction and end-diastolic volume index were increased. Although the ventricular wall thickness remained constant, the systolic anterior motion of the mitral valve and A/E were reduced during the pacing period in the echocardiography. During the acute effect of DDD pacing, the pressure gradient reduction seemed to be related to dilatation of the left ventricular outflow tract induced by a change of contraction modality of the intraventricular septum. Improved left ventricular diastolic function may contribute to the pressure gradient reduction during extended periods of pacing therapy.

Cardiac Pacing, Artificial↗
PubMed1996

Bacillus stearothermophilus qcr operon encoding rieske FeS protein, cytochrome b6, and a novel-type cytochrome c1 of quinol-cytochrome c reductase.

The gcr of Bacillus stearothermophilus K1041 encoding three subunits of the quinol-cytochrome c oxidoreductase (cytochrome reductase, b6c1 complex) was cloned and sequenced. The gene (qcrA) for a Rieske FeS protein of 19,144 Da with 169 amino acid residues, and the gene (qcrC) for cytochrome c1 of 27,342 Da with 250 amino acid residues were found at adjacent upstream and downstream sides of the previously reported qcrB (petB) for cytochrome b6 of subunit 25,425 Da with 224 residues (Sone, N., Sawa, G., Sone, T., and Noguchi, S. (1995) J. Biol. Chem. 270, 10612-10617). The three structural genes for thermophilic Bacillus cytochrome reductase form a transcriptional unit. In the deduced amino acid sequence for the FeS protein, the domain including four cysteines and two histidines binding the 2Fe-2S cluster was conserved. Its N-terminal part more closely resembled the cyanobacteria-plastid type than the proteobacteria-mitochondria type when their sequences were compared. The amino acid sequence of cytochrome c1 was not similar to either type; the thermophilic Bacillus cytochrome c1 is composed of an N-terminal part corresponding to subunit IV with three membrane-spanning segments, and a C-terminal part of cytochrome c reminiscent of cytochrome c-551 of thermophilic Bacillus. The subunit IV in the enzyme of cyanobacteria and plastids is the counterpart of C-terminal part of cytochrome b of proteobacteria and mitochondria. These characteristics indicate that Bacillus cytochrome b6c1 complex is unique.

Amino Acid Sequence↗
PubMed1996

Elevated serum level of soluble HLA class I antigens in patients with systemic lupus erythematosus.

OBJECTIVE: To examine the clinical significance of serum soluble HLA class I antigens (sHLA class I) in patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). METHODS: Serum levels of sHLA class I were measured by enzyme-linked immunosorbent assay, using a monoclonal antibody against monomorphic determinant of HLA class I (W6/32) and an enzyme-labeled polyclonal antibody to human beta 2-microglobulin. RESULTS: The serum sHLA class I concentration was 1.85 +/- 1.15 micrograms/ml (mean +/- SD) in 27 patients with SLE (P < 0.0001 versus normal controls, P = 0.0001 versus RA), 0.61 +/- 0.34 micrograms/ml in 16 patients with RA (P = 0.02 versus normal controls), and 0.41 +/= 0.20 micrograms/ml in normal controls. The HLA class I levels were significantly correlated with the SLE Disease Activity Index (r = 0.62, P = 0.0004) and with a reduction of CH50 levels (r = -0.60, P = 0.0007). A longitudinal analysis of patients with SLE indicated that serum sHLA class I levels fluctuated in conjunction with other disease activity markers. CONCLUSION: Serum sHLA class I may be useful as a disease activity marker of SLE. The mechanism of secretion and the physiologic role of sHLA class I require further study.

Adolescent↗