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S Noda

Publications and source records attributed to S Noda.

At least 73 records · Page 4Linked to original sources
PubMed1999

Necessity of repeat biopsies in men for suspected prostate cancer.

BACKGROUND: The indications for repeat prostate needle biopsy in men whose initial biopsy results revealed no evidence of cancer are not defined. METHODS: We retrospectively studied 218 consecutive cases of men undergoing prostate biopsies for suspected cancer. Men in whom cancer was found on repeat biopsy were compared with others with regard to age, digital rectal examination, serum prostate-specific antigen (PSA) concentration, prostate volume, PSA density, PSA slope and the frequency of prostatic intraepithelial neoplasia (PIN) on initial prostate biopsy. RESULTS: Of the 114 cancers detected, 99 (87%) were diagnosed on initial biopsy and 15 (131%) were diagnosed on repeat biopsy. Mean PSA concentration and mean PSA density were significantly higher in patients with cancer on initial biopsy than on repeat biopsy (P<0.05), but they were similar among patients with and without cancer on repeat biopsy. The PSA slope showed a more progressive increase in patients with cancer on repeat biopsy than in those patients without cancer at 6 month intervals. Of the 218 patients undergoing prostate biopsy, seven (3.2%)) were identified with high grade PIN but without concurrent prostate cancer. Prostate cancers were detected in two of these seven patients (29%) on repeat biopsy. CONCLUSIONS: Serum PSA levels and PSA density did not provide useful predictive information about the indications of repeat biopsy. We conclude that men with a more progressive increase in PSA levels at 6 months intervals and high grade PIN on prostate needle biopsy should undergo repeat sampling to exclude missed cancer.

Aged↗
PubMed1999

Translocation of tyrosine-phosphorylated TCRzeta chain to glycolipid-enriched membrane domains upon T cell activation.

Recent studies point to glycolipid-enriched membrane (GEM) microdomains as the critical sites for TCR-mediated signal transduction. However, whether the TCR complex is localized in the GEM domain is not well-defined. In the present study, we analyzed localization of the TCR-CD3 complex in the GEM domain by isolating the GEM fraction with sucrose density gradient centrifugation. Although 10% of TCRzeta chains was localized in the GEM fraction, most of the TCR complexes were excluded from the GEM before and after T cell activation, and the amount of TCRzeta in the GEM was not increased after activation. However, the tyrosine-phosphorylated form of TCRzeta was strongly concentrated in the GEM fraction upon TCR engagement. A kinetic study revealed that tyrosine phosphorylation of TCRzeta occurred initially in the Triton X-100-soluble membrane fraction followed by the accumulation of phosphorylated TCRzeta in the GEM. Thus, these results indicate that phosphorylated TCRzeta migrates into the GEM domains on T cell activation. We speculate that the GEM microdomains may function as a reservoir of activation signals from triggered TCR.

Animals↗
PubMed1999

Phylogenetic diversity of nitrogen fixation genes in the symbiotic microbial community in the gut of diverse termites.

Nitrogen fixation by the microorganisms in the gut of termites is one of the crucial aspects of symbiosis, since termites usually thrive on a nitrogen-poor diet. The phylogenetic diversity of the nitrogen-fixing organisms within the symbiotic community in the guts of various termite species was investigated without culturing the resident microorganisms. A portion of the dinitrogenase reductase gene (nifH) was directly amplified from DNA extracted from the mixed population in the termite gut. Analysis of deduced amino acid sequences of the products of the clonally isolated nifH genes revealed the presence of diverse nifH sequences in most of the individual termite species, and their constituents were considerably different among termite species. A majority of the nifH sequences from six lower termites, which showed significant levels of nitrogen fixation activity, could be assigned to either the anaerobic nif group (consisting of clostridia and sulfur reducers) or the alternative nif methanogen group among the nifH phylogenetic groups. In the case of three higher termites, which showed only low levels of nitrogen fixation activity, a large number of the sequences were assigned to the most divergent nif group, probably functioning in some process other than nitrogen fixation and being derived from methanogenic archaea. The nifH groups detected were similar within each termite family but different among the termite families, suggesting an evolutionary trend reflecting the diazotrophic habitats in the symbiotic community. Within these phylogenetic groups, the sequences from the termites formed lineages distinct from those previously recognized in studies using classical microbiological techniques, and several sequence clusters unique to termites were found. The results indicate the presence of diverse potentially nitrogen-fixing microbial assemblages in the guts of termites, and the majority of them are as yet uncharacterized.

Animals↗
PubMed1999

Culture-independent characterization of a gene responsible for nitrogen fixation in the symbiotic microbial community in the gut of the termite Neotermes koshunensis.

Expression of the nitrogen fixation gene, nifH, in the gut of the termite Neotermes koshunensis was characterized without cultivation. nifH cDNA was directly amplified from mRNA of the mixed microbial population in the gut by reverse transcription (RT)-PCR. Analyses of the RT-PCR products revealed that, among the diverse nifH sequences, only a few corresponding to an alternative nitrogenase (encoded by the anf gene) were preferentially transcribed in the termite gut. Expression of the anf gene was further investigated quantitatively under several termite feeding conditions by competitive PCR. The levels of expression of the anf gene were largely congruent with the nitrogen fixation activity displayed by the termite. The amounts of the genomic anf gene in the population showed no significant change, indicating that the level of expression was critical for nitrogen fixation activity. Interestingly, no significant decrease in the expression level was observed when the diet contained molybdenum (Mo), which represses ordinary anf genes. A 3.6-kb DNA region downstream of the anf gene was isolated and found to contain reading frames homologous to anfH, anfD, and anfG of the Bacteria domain which encode subunits of an alternative nitrogenase having no Mo as a cofactor. This DNA region also contained reading frames encoding glnB-like proteins, which is a common feature of the nitrogenase genes of the Archaea domain. These results indicate that the anf group of nitrogenase genes is the most important group of genes responsible for nitrogen fixation in N. koshunensis and that the anf gene possesses novel features with respect to the regulation of its expression and its gene organization.

Animals↗
PubMed1999

Decreased regional cerebral metabolic rate for glucose in systemic lupus erythematosus patients with psychiatric symptoms.

To determine brain functional abnormality in systemic lupus erythematosus (SLE) patients with psychiatric symptoms, we evaluated 12 active SLE patients with or without psychiatric symptoms by means of [18F]2-fluoro-2-deoxy-D-glucose positron emission tomography (PET), magnetic resonance imaging and neuropsychological testing. Patients with psychiatric symptoms showed significantly poorer performance in tests which subserved attentional function. The PET study revealed that the psychiatric patients had significantly decreased regional cerebral metabolic rates for glucose in the prefrontal, inferior parietal and anterior cingulate regions. Prefrontal, inferior parietal and anterior cingulate dysfunction may be related to attentional deficits that are involved in various psychiatric symptoms in SLE. PET is an invaluable tool to reveal such brain functional abnormality seen in SLE patients with psychiatric symptoms.

Adolescent↗
PubMed1999

Effects on growth of rat offspring born from dams treated subcutaneously with a surfactant, polyoxyethylene(10)nonylphenyl ether(NP-10), during lactational period.

A surfactant NP-10 was administered subcutaneously to Jcl:Wistar female rats at dose levels of 5, 20 and 80 mg/kg/day from date of birth to day 21 after birth of F1 offspring to assess its effects on the growth, behavior and functions of the offspring. For F0 dams, scab formation and loss of hair at the test substance administration site were observed in all treatment groups and induration of the skin at the test substance administration site in the 20 and 80 mg/kg groups in general condition and necropsy findings at the end of the dosing period. In necropsy findings, in addition to these changes, hemorrhage and whitish change of the subcutis at the test substance administration site were seen in all treatment groups, adhesion to the somatic muscles and granulation of the subcutis at the test substance administration site in the 20 and 80 mg/kg groups, and swelling of the spleen and adrenals in the 80 mg/kg group. Reduction or a tendency for reduction in food consumption was also detected from the initial day of dosing (day 0) to day 17 after birth F1 offspring in the 80 mg/kg group. Body weight or the findings on the day after birth and day of weaning failed to reveal any evidence of an effect that could be ascribed to the test substance. In F1 born offspring, a decrease or tendency for decrease in body weight was observed from day 7 after birth in both sexes and for females during the gestation period in the 80 mg/kg group. However, body weight gains based on the weights at 4 weeks after birth or on day 0 of gestation in the 80 mg/kg group failed to reveal any difference from that in the control group. The observation on the day of birth and during the period of lactation, physical development test, reflex test, general condition, open-field test, water-maze test, reproductive ability test, observations at cesarean section, necropsy findings, organ weights, histopathological findings of females or males that did not achieve successful gestation, skeletal examination, and the observations at cesarean section and external examination of F2 fetuses failed to reveal any evidence that could be ascribed to the test substance. These results indicate that NP-10 had no effect on the behavior or functions of the offspring, although it affected the growth of the offspring born, under the conditions of this study. The non-effective dose level is considered to be 20 mg/kg for general toxicity of the dams and for their offspring.

Abnormalities, Drug-Induced↗
PubMed1999

Arterial conduits.

Explore the source record for details and available documents.

Coronary Artery Bypass↗
PubMed1999

Molecular detection of heparan sulfate proteoglycan mRNA in rat kidney during calcium oxalate nephrolithiasis.

The present study used reverse transcription (RT)-PCR to examine heparan sulfate proteoglycan (HSPG) mRNA expression in rat kidneys. Total mRNA in kidney was isolated and converted to cDNA. To confirm the exact expression level of HSPG mRNA, quantitative competitive (QC)-PCR was performed for each sample. PCR products were resolved by electrophoresis on 1.5% agarose gel and visualized with ethidium bromide. Fragment intensity and area were measured using an image analyzer. In QC-PCR, target DNA and competitive DNA were expressed, using gene-specific primer for HSPG mRNA, as 506- and 345-bp bands, respectively. The level of HSPG mRNA expression apparently increased in the nephrolithic rat kidney. Immunohistochemical study revealed that increased production of heparan sulfate was detected in both distal and proximal tubules during nephrolithiasis. These findings suggest that increased expression of HSPG may play a significant role during calcium oxalate stone formation.

Animals↗
PubMed1999

[A case of cerebellar degeneration showing amaurosis fugax due to primary angle-closure glaucoma].

We reported a 76-year-old woman with cerebellar degeneration who had transient monocular visual loss following the acute attacks of angle-closure glaucoma. The episodes occurred only at night approximately every ten days. She denied pain or any other associated symptoms. Ophthalmological examinations including intraorbital pressure, ocular fundus, visual acuity and visual field showed no abnormalities between the attacks. Provisional diagnosis on admission was amaurosis fugax from retinal embolization. After admission, she developed a typical acute attack of glaucoma accompanied by severe pain in her left eye. Intraorbital pressures were 12 mmHg in the right eye and 58 mmHg in the left, and the diagnosis of primary angle-closure glaucoma was made gonioscopically. Following peripheral iridotomy by laser therapy, her visual acuity recovered and episodes of visual loss disappeared. In this case, the attacks of glaucoma were unusually painless, so it is very difficult to distinguish between glaucoma and amqurosis fugax from retinal embolization. The transient visual loss always occurred at night, and retrospectively, this characteristic feature might indicate that these episodes were acute attacks of angle-closure glaucoma. Glaucoma is one of the diseases that can cause painless amaurosis fugax.

Aged↗
PubMed1998

Characterization of muscarinic receptors in the human melanoma cell line SK-Mel-28 via calcium mobilization.

In melanoma cells of primary and metastatic human melanomas muscarinic cholinergic receptors are present. Muscarinic receptors were shown to be expressed in morphogenetically active embryonic cells. Therefore, the possibility exists that in melanomas an embryonic trait is re-expressed after transformation. In the present study, we demonstrated the presence of muscarinic receptors in the human melanoma cell line SK-Mel-28 by immunofluorescence with the monoclonal antibody M 35 and characterized the receptors further by measuring calcium mobilization after muscarinic stimulation. Cell suspensions were stained with fura-2 and fluorescence was followed at 380 nm excitation in a fluorimeter cuvette. After the addition of acetylcholine or carbachol a steep decrease in fluorescence intensity indicated calcium mobilization from intracellular stores (peak reaction), which was followed by a constantly lowered fluorescence level indicating a steady influx of extracellular calcium in the presence of agonist. By quantitative evaluation, dose-response curves were obtained from which an ED of 4.3 x 10(-6) M was calculated for acetylcholine and an ED of 2.2 x 10(-5) M was calculated for carbachol. After preincubation with antagonists the dose-response curve of acetylcholine was shifted to the right. The inhibition constant of pirenzepine was calculated as 3.9 x 10(-7) M, of methoctramine as 6.8 x 10(-7) M and of 4-DAMP-mustard as 1.9 X 10(-8) M. Comparison with the data from the literature and those obtained in the chick embryo indicates that the muscarinic receptor in SK-Mel-28 melanoma cells pharmacologically behaves as the M3 type and corresponds to the embryonic muscarinic receptor characterized by us in earlier studies.

Atropine↗
PubMed1998

Human retina-specific amine oxidase: genomic structure of the gene (AOC2), alternatively spliced variant, and mRNA expression in retina.

Previously, we reported the isolation of cDNA for human retina-specific amine oxidase (RAO) and the expression of RAO exclusively in retina. Bacterial artificial chromosome clones containing the human RAO gene (AOC2) were mapped to human chromosome 17q21 (Imamura et al., 1997, Genomics 40: 277-283). Here, we report the complete genomic structure of the RAO gene, including 5' flanking sequence, and mRNA expression in retina. The human RAO gene spans 6 kb and is composed of four exons corresponding to the amino acid sequence 1-530, 530-598, 598-641, and 642-729 separated by three introns of 3000, 310, and 351 bp. Screening of a human retina cDNA library revealed the existence of an alternatively spliced cDNA variant with an additional 81 bp at the end of exon 2. The sizes of exons and the locations of exon/intron boundaries in the human RAO gene showed remarkable similarity to those of the human kidney diamine oxidase gene (AOC1). In situ hybridization revealed that mRNA coding for RAO is expressed preferentially in the ganglion cell layer of the mouse retina. We designed four sets of PCR primers to amplify four exons, which will be valuable for analyzing mutations in patients with ocular diseases affecting the retinal ganglion cell layer.

Alternative Splicing↗
PubMed1998

Relation of interferon therapy and hepatocellular carcinoma in patients with chronic hepatitis C. Osaka Hepatocellular Carcinoma Prevention Study Group.

BACKGROUND: The effect of interferon therapy on the incidence of hepatocellular carcinoma in chronic hepatitis C is poorly defined. OBJECTIVE: To compare the incidence of hepatocellular carcinoma in interferon-treated patients with chronic hepatitis C to that of historical controls and to examine whether response to therapy is related to incidence of hepatocellular carcinoma in patients with chronic hepatitis C. DESIGN: Retrospective cohort study. SETTING: One university hospital and seven university-affiliated hospitals. PATIENTS: 419 consecutive patients with chronic hepatitis C who started interferon therapy between January 1992 and December 1993 (interferon group) and 144 patients with chronic hepatitis C who had liver biopsy between January 1986 and December 1989 and did not receive interferon (controls). INTERVENTION: Patients in the interferon group received human lymphoblastoid interferon, recombinant interferon-alpha2a, or recombinant interferon-alpha2b for 6 months. MEASUREMENTS: The end point was development of hepatocellular carcinoma on abdominal ultrasonography or computed tomography. Sustained response was defined as persistent normalization of alanine aminotransferase (ALT) levels during interferon therapy and follow-up. Relapse was defined as a normal serum ALT level at the end of treatment with an increase to an abnormal level after cessation of treatment. Nonresponse included all other ALT patterns. RESULTS: Median follow-up in the interferon and control groups was 47.6 and 46.8 months, respectively. During follow-up, hepatocellular carcinoma was found in 28 interferon-treated patients and 19 controls. Cox proportional hazards regression analysis that included all patients revealed that interferon therapy (P=0.041), older age (P=0.003), greater histologic activity (P=0.029), and higher histologic stage (P=0.049) were independent factors associated with the development of hepatocellular carcinoma. The risk ratios for development of hepatocellular carcinoma in patients with sustained response, relapse, and nonresponse were 0.06 (95% CI, 0.01 to 0.46), 0.51 (CI, 0.20 to 1.27), and 0.95 (CI, 0.48 to 1.84), respectively, compared with controls. CONCLUSIONS: The incidence of hepatocellular carcinoma was lower in patients with sustained response to interferon therapy than historical controls and nonresponders. Interferon therapy may decrease the risk for hepatocellular carcinoma in patients with chronic hepatitis C.

Alanine Transaminase↗
PubMed1998

Mouse myocilin (Myoc) gene expression in ocular tissues.

Human myocilin is identical to TIGR (trabecular meshwork inducible glucocorticoid response) which is responsible for the pathogenesis of juvenile-onset primary open angle glaucoma (GLCIA). We have isolated cDNA for mouse myocilin (Myoc) and investigated mouse myocilin gene expression in ocular tissues with in situ RNA hybridization. Hybridization signals were observed in the iris, ciliary body, trabecular meshwork, sclera, and retina in the mouse eye. The marked signals were seen in trabecular meshwork cells and the anterior portion of sclera. These findings suggest that myocilin mutation could affect the capacity of aqueous outflow and cause elevation of the intraocular pressure which is involved in the pathogenesis of glaucoma.

Amino Acid Sequence↗
PubMed1998

Physical and functional association between thymic shared antigen-1/stem cell antigen-2 and the T cell receptor complex.

Thymic shared antigen-1 (TSA-1)/stem cell Ag-2 (Sca-2) is a glycosylphosphatidylinositol (GPI)-anchored antigen expressed on lymphocytes. We have previously demonstrated that a signal via TSA-1/Sca-2 inhibits T cell receptor (TCR)-mediated T cell activation and apoptosis. To elucidate a molecular mechanism for TSA-1-mediated modulation of the TCR-signaling pathway, we examined whether TSA-1 is physically coupled to the TCR in the present study. TSA-1 was clearly associated with CD3zeta chains in T cell hybridomas, activated T cells, and COS-7 cells transfected with TSA-1 and CD3zeta cDNA. The physical association was confirmed on the surface of T cells in immunoprecipitation and confocal microscopy. The analysis using stable and transient transfectants expressing a transmembrane form of TSA-1 revealed that the association of CD3zeta did not require the GPI anchor of TSA-1. Finally, tyrosine phosphorylation of CD3zeta chains was induced after stimulation with anti-TSA-1, suggesting that a functional association between these two molecules also exists. These results imply that the physical association to CD3zeta underlies a regulatory role of TSA-1/Sca-2 in the TCR-signaling pathway.

Animals↗
PubMed1998

Apoptosis in the lens anlage of the heritable lens aplastic mouse (lap mouse).

Adult homozygous lap mice show various eye abnormalities, such as aphakia, retinal disorganization, and dysplasia of the cornea and anterior chamber. In the fetal eye of a homozygous lap mouse, the lens placode seems to develop normally. However, the lens vesicle progresses abnormally to form a mass of cells without a cavity, and the mass vanishes soon afterward. We examined cell death in the lens anlage of this mutant. The lens anlagen of homozygous lap and normal mice from days 10 to 12 of gestation were observed by light microscopy after DNA end-labeling by immunohistochemistry and by transmission electron microscopy. By light microscopy, a slight frequency of cell death was detected in the lens anlage encircling the surface ectoderm and in the anlage or in the anlage of both homozygous lap mice and normal mice at day 10 of gestation. Cell death was seen in the lens anlage encircling the surface ectoderm in the normal mouse and sporadically in the anlage of the homozygous lap mouse at day 10.5 of gestation. Cell death was visible at the area of the lens vesicle attached to the surface ectoderm and encircling the surrounding surface ectoderm in the normal mouse, and in the lens anlage encircling the surface ectoderm and the apex areas of the lens anlage in the homozygous lap mouse at day 11 of gestation. At day 12 of gestation, almost no cell death was observed in the lens anlage of the normal mouse. However, extensive areas of cell death were still seen in the lens anlage at its apex, at the inner region, and encircling the surface ectoderm in the homozygous lap mouse. Electron microscopic observation showed that the dead cells observed in the lens anlagen by light microscopy in normal and lap mice are the result of apoptosis. In lap mice, cells with cytoplasmic condensation were observed mainly at days 10 and 10.5 of gestation. Many apoptotic bodies which had been phagocytosed by adjacent cells were seen predominantly at day 11 of gestation. At day 12 of gestation, apoptotic bodies phagocytosed by adjacent cells, which were seen at day 11, were still predominant, but there were more apoptotic bodies per cell and more digested apoptotic bodies than at day 11. These results indicate that cell death, resulting from apoptosis is involved in the disappearance of the lens anlage of lap mice.

Animals↗
PubMed1998

Molecular phylogenetic identification of the intestinal anaerobic microbial community in the hindgut of the termite, Reticulitermes speratus, without cultivation.

A termite maintains an anaerobic microbial community in its hindgut, which seems to be the minimum size of an anaerobic habitat. This microbial community consists of bacteria and various anaerobic flagellates, and it is established that termites are totally dependent on the microbes for the utilization of their food. The molecular phylogenetic diversity of the intestinal microflora of a lower termite, Reticulitermes speratus, was examined by a strategy that does not rely on cultivation of the resident microorganisms. Small subunit ribosomal RNA (ssrRNA) genes were directly amplified from the mixed-population DNA of the termite gut by polymerase chain reaction (PCR) and clonally isolated. Most sequenced clones were phylogenetically affiliated with the four major groups of the domain Bacteria: the Proteobacteria group, the Spirochete group, the Bacteroides group, and the Low G + C gram-positive bacteria. The 16S rRNA sequence data show that the majority of the intestinal microflora of the termite consists of new species that are yet to be cultured. The phylogeny of a symbiotic methanogen inhabiting the gut of a lower termite (R. speratus) was analyzed without cultivation. The nucleotide sequence of the ssrDNA and the predicted amino acid sequence of the mcrA product were compared with those of the known methanogens. Both comparisons indicated that the termite symbiotic methanogen belonged to the order Methanobacteriales but was distinct from the known members of this order. The diversity of nitrogen-fixing organisms was also investigated without culturing the resident microorganisms. Fragments of the nifH gene, which encodes the dinitrogenase reductase, were directly amplified from the mixed-population DNA of the termite gut and were clonally isolated. The phylogenetic analysis of the nifH amino acid sequences showed that there was a remarkable diversity of nitrogenase genes in the termite gut. The molecular phylogeny of a symbiotic hypermastigote Trichonympha agilis (class Parabasalia; order Hypermastigida) in the hindgut of R. speratus was also examined by the same strategy. The whole-cell hybridization experiments indicated that the sequence originated from a large hypermastigote in the termite hindgut, Trichonympha agilis. According to the phylogenetic trees constructed, the hypermastigote represented one of the deepest branches of eukaryotes. The hypermastigote along with members of the order Trichomonadida formed a monophyletic lineage, indicating that the hypermastigote and trichomonads shared a recent common ancestry.

Animals↗