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Biomedical subjects

S Watanabe

Publications and source records attributed to S Watanabe.

At least 217 records · Page 12Linked to original sources

Lymph folliculitis in ulcerative colitis.

Preferential involvement of the appendix has recently been confirmed in ulcerative colitis. Since the appendix is an aggregate of lymph follicles, this new observation implies a critical role of the lymph follicles, of both the large bowel and the appendix, in an etiopathogenesis of ulcerative colitis. This report presents two cases of ulcerative colitis in which lymph folliculitis and lymphoid hyperplasia were observed. Lymph folliculitis was observed endoscopically in a border between an established lesion and an uninvolved area. Case 1, proctitis type, relapsing remitting, mild in severity, showed lymph folliculitis in a proximal border of an established rectal lesion. Case 2, with left-sided colitis, mild in severity, had a skip appendiceal orifice inflammation. Lymph folliculitis was observed in the cecum surrounding established appendiceal orifice inflammation. In both cases, lymphoid hyperplasia was observed in an uninvolved area with clear vascular patterns. These two cases clearly demonstrate the involvement of gut lymph follicles in ulcerative colitis. Lymph folliculitis and/or lymphoid hyperplasia was proposed to be early lesions in ulcerative colitis. In addition, the need for microbiology targeting lymph follicles of the large bowel and appendix is stressed in order to disclose the casual microbial agents in ulcerative colitis.

Adult↗

Staphylococcus aureus in inflammatory bowel disease.

BACKGROUND: The potential role of superantigens in inflammatory bowel disease (IBD), particularly Crohn disease, has been broached in studies of the functions of T cell receptors. Staphylococcal cells have been found in intestinal lymph follicles of IBDs. To clarify a role of staphylococcal superantigens in IBD, we attempted to determine whether Staphylococcus aureus could be detected in intestinal mucosa, including surgical specimens and lymph follicles of initial cases. METHODS: One-hundred-and-six colonic and ileal specimens were obtained from 38 Crohn disease, 25 ulcerative colitis and 36 non-IBD patients through therapeutic surgery or endoscopic biopsy. In Crohn disease, 23 surgical specimens and 11 biopsy specimens from initial cases were included. DNA was extracted with phenol-chloroform after homogenization and proteinase K treatment in 73 mucosal specimens. Using an inverted microscope, lymph follicle tissue was microdissected from the remaining 33, mostly biopsy, specimens. DNA was then extracted by freeze-thawing. A coagulase gene characteristic of S. aureus was sought. A nested polymerase chain reaction was performed utilizing primers that amplify a region of the coagulase gene. Polymerase chain reaction products were analyzed with polyacrylamide gel electrophoresis. RESULTS: Only one surgically resected colonic specimen, from a 42-year-old male ulcerative colitis patient, registered positive staphylocoagulase amplification. CONCLUSIONS: Staphylococcal superantigens are not involved in either the early lesions or the established lesions of Crohn disease. However, S. aureus infection occasionally may occur during the course of IBD.

Adult↗

The genetic diversity of clinical isolates of Malassezia pachydermatis from dogs and cats.

Molecular investigation of 110 clinical isolates of non-lipid-dependent Malassezia pachydermatis from dogs and cats was carried out by random amplification of polymorphic DNA (RAPD) and chitin synthase 2 (CHS2) gene sequence analyses. The RAPD analysis indicated that the clinical isolates of M. pachydermatis constituted four distinct genetic types (A, B, C and D). Moreover, the results from CHS2 gene analysis completely agreed with those from the RAPD analyses. The clinical isolates of M. pachydermatis were obtained from normal external ears, lesions of atopic dermatitis, flea allergic dermatitis, otitis externa, pyoderma and seborrheic dermatitidis in dogs and cats. Type A consisted of 93 clinical isolates as well as the ex-neotype strain of M. pachydermatis. The isolates of type A M. pachydermatis originated from lesions of all kinds of diseases. They were predominant on dog and cat skin. The other types, B, C, and D were isolated mainly from otitis externa.

Animals↗

Detection of occlusal caries under sealants by use of a laser fluorescence system.

OBJECTIVE: In recent years, various dental caries diagnosis systems, including digital radiography, light fluorescence, and lasers, have been developed. The aim of this study was to evaluate the new laser fluorescence system known as DIAGNOdent for its ability to detect occlusal caries under sealants. BACKGROUND DATA: Fluorescence induced by laser light for early diagnosis of enamel caries was introduced by Bjelkhagen et al. in 1982, but these systems were difficult to use in the oral cavity. Recently, DIAGNOdent has been shown to have a higher diagnostic validity for the detection and quantification of caries lesions than the electronic caries monitor and to have a higher reproducibility for measurements, according to work by Lussi et al. in 1999. The laser diagnosis system is able to indicate the value of reflected fluorescence on a digital display. This value is associated with the carious progression. METHODS: Thirty-two extracted permanent premolars and molars that had occlusal dental caries were used in this study. The reflected fluorescence was measured by use of DIAGNOdent at the occlusal surface of the tooth before and after chemical irrigation, acid etching, and application of a light-cured fluoride releasing sealant. The measurements were two or three points per experimental tooth. A total of 53 points on the experimental teeth was evaluated. RESULTS: The mean reflected fluorescence value was significantly decreased by chemical irrigation; however, no difference was noted between the value before and the salve after acid etching. These teeth were divided into three groups: clear, red, and white as tooth color sealants of the tooth. The reflected fluorescence value before and after sealants was tested for statistical significance. The diagnosis of caries under sealants was up to 10 of reflected fluorescence value in the study. Clear and red sealants were used to reveal caries under sealants using visual inspection, and all sealants groups achieved 90% of reflected fluorescence value after sealants application. However, the white sealants did not reveal caries through visual inspection. The detection ability of caries under white sealants was 53.5% (n = 23/42). CONCLUSIONS: This laser diagnosis system makes it easy to detect the existence of caries under a pit and fissure sealant during a routine check-up.

Dental Caries↗

Validity and reproducibility of a self-administered food-frequency questionnaire to assess isoflavone intake in a japanese population in comparison with dietary records and blood and urine isoflavones.

Valid food-frequency questionnaires (FFQ) need to be developed to assess isoflavone intake in investigations of its possible association with the lower incidence of breast and prostate cancer in Asian countries. We investigated the validity and reproducibility of isoflavone (daidzein and genistein) intakes from self-administered semiquantitative FFQ used in the JPHC Study (Japan Public Health Center-based Prospective Study on Cancer and Cardiovascular Diseases). We also investigated the number of food items that would be sufficient to ensure validity and reproducibility. We collected FFQ, dietary records (DR), blood and urine samples from 215 subjects among JPHC Study participants, estimated isoflavone intakes from FFQ and DR, and measured serum isoflavone concentration and urine isoflavone excretion. For daidzein, mean intakes estimated from FFQ and DR, serum concentration and urine excretion were 18.3 mg/d, 14.5 mg/d, 119.9 nmol/L and 17.0 micromol/d and for genistein, 31.4 mg/d, 23.4 mg/d, 475.3 nmol/L and 14.2 micromol/d, respectively. Results were similar when analyzed by sex. Spearman correlation coefficients for daidzein of energy-adjusted intakes from FFQ with those from DR, serum concentration and creatinine-adjusted urinary excretion were 0.64, 0.31 and 0.43, respectively. Correlations between two FFQ estimates with a 1-y interval were 0.76. Results were similar for genistein. The shorter version of the FFQ with three items (natto, miso and tofu for miso soup) showed a similar correlation. The original FFQ and the shorter versions have sufficient validity and reproducibility to be used in epidemiologic studies.

Diet Records↗

Dietary fructooligosaccharides modify intestinal bioavailability of a single dose of genistein and daidzein and affect their urinary excretion and kinetics in blood of rats.

The influence of dietary fructooligosaccharides (FOS) on bioavailability of genistein and daidzein in rats was estimated by measuring their concentrations in plasma collected from three different veins and in urine after a single intragastric administration of isoflavone conjugates. Sprague-Dawley male rats (6 wk old, n = 22) were fed a purified control (AIN-93G) diet or a FOS diet (AIN-93G + 5% FOS) for 7 d. A single dose of soy isoflavone conjugates, i.e., 8.5 mg as genistein and 33 mg as daidzein/kg body, was administered via a stomach tube at d 5. Blood samples were collected after administration via catheters in the portal and central veins and by puncture of the tail vein. The isoflavones in plasma and urine were analyzed by time-resolved fluoroimmunoassay. The genistein concentration in the portal blood increased rapidly, reaching a peak of 3.5 micromol/L in both groups at 1 h after administration. The concentrations in the central and tail venous blood were approximately half of those in the portal blood. In the FOS-fed group, both genistein and daidzein remained detectable at 24 and 48 h in the tail venous plasma. The urinary excretion of both isoflavones in the 24- to 48-h period after administration was significantly higher in the FOS-fed group than in the control group. The difference between the portal and central veins indicated hepatic uptake, probably leading to conjugation of aglycones and excretion into bile. FOS modified the absorption and enterohepatic recirculation of isoflavones.

Animals↗

Changes in major blood components after adopting the supine position during haemodialysis.

BACKGROUND: In Japan, haemodialysis (HD) is usually performed with patients in the supine position. However, the effects of changing posture on major blood components have not been investigated in HD patients. It is possible that several fluid components change rapidly when patients change from the upright to the supine position. We therefore investigated the effects of posture on blood component analysis. METHODS: A first blood sample was taken from 10 HD patients 5 min after they adopted a supine position; HD was begun immediately after sampling. Additional blood samples were collected 15 and 30 min later while patients remained in the supine position. On an alternate day, blood samples were taken from these same patients in the supine position, but not during HD. The same procedure was performed in 10 healthy volunteers. RESULTS: Haematocrit significantly decreased in patients undergoing HD at 15 and 30 min into the HD session. Similar decreases were observed in HD patients not undergoing HD and in normal control subjects. Haematocrit changes at 15 min were not significantly different between the three groups. Serum albumin concentrations decreased in the same way as haematocrit. Consequently, the reductions in haematocrit and albumin concentrations in HD patients during the HD session were not attributable to the HD procedure or to end-stage renal disease, but rather were due to the supine position and consequent haemodilution caused by redistribution of water from the extra- to the intravascular space. Finally, WBC counts decreased significantly at 15 min in both HD patient groups and in normal controls. The relative decrease at 15 min was significantly greater in HD patients undergoing HD (61.4% of baseline) than in those not undergoing HD (88.0%) or in normal controls (94.7%). These differences were probably due to previously reported WBC sequestration in the lungs during the early phase of HD. CONCLUSIONS: This study suggests that the change from the upright to the supine positions during HD causes changes in blood components that are critical for quality control determinations.

Adult↗

Neuroreceptors and ion channels as targets of alcohol.

This article represents the proceedings of a symposium at the 2000 ISBRA Meeting in Yokohama, Japan. The chairs were Toshio Narahashi and Kinya Kuriyama. The presentations were (1) Modulation of neuroreceptors and ion channels by alcohol, by T. Narahashi; (2) Inhibition by ethanol of NMDA and AMPA receptor-channels, by P. Illes, K. Wirkner, W. Fischer, K. Mühlberg, P. Scheibler, and C. Allgaier; (3) Effects of ethanol on metabotropic glutamate receptors, by K. Minami; (4) Acute alcohol actions on the 5-HT3 ligand-gated ion channel, by D. Lovinger; (5) Inhibition of NMDA receptors by MK801 attenuates ethanol-induced taurine release from the hippocampus, by F. Lallemand, R.J. Ward, and P. DeWitte; and (6) Effect of ethanol on voltage-operated Ca2+ channels in hepatic stellate cells, by T. Itatsu, Y. Takei, H. Oide, M. Hirose, X. E. Wang, S. Watanabe, M. Tateyama, R. Ochi, and N. Sato.

Animals↗

Surgical treatment for pancreatic metastasis from soft-tissue sarcoma: report of two cases.

We present two cases in which a soft-tissue sarcoma metastasized to the pancreas, but both patients survived as a result of repetitive surgical treatment during a 6- to 10-year period. The first case was a 29-year-old man who had a history of removal of mesenchymal chondrosarcoma in the left thigh in 1986 and who underwent distal pancreatectomy and the enucleation of a tumor in the head of the pancreas because of the development of three metastatic lesions in 1989. Afterward, although metastases were found in other organs, they were resected each time (for a total of five times) and the patient has survived over 10 years. The second case was a 40-year-old woman who had a history of the removal of synovial sarcoma in the right thigh and had 6 surgical resections of local or pulmonary recurrent tumors. She underwent pylorus-preserving pancreaticoduodenectomy in 1993 because of the development of a solitary metastatic lesion in the pancreas and survived more than 6 years after the pancreatectomy. Our report suggests, in selected cases, that long-term survival from pancreatic metastasis of soft-tissue sarcoma is expected as a result of curative resection. However, because pancreatic metastasis has a potential to recur in other organs, it is necessary to take aggressive surgical procedures repeatedly for the treatment of recurrences to improve prognosis after pancreatectomy.

Adult↗

Detection of myocardial viability using rest-redistribution thallium-201 imaging in a stress 99Tcm-tetrofosmin/rest thallium-201 dual-isotope protocol.

This study investigated the utility of optional thallium-201 (201Tl) imaging for detecting myocardial viability in the stress 99Tcm-tetrofosmin/rest 201Tl dual-isotope protocol. Seventy-nine patients with old myocardial infarction and 25 patients with acute myocardial infarction underwent acquisition of three consecutive 201Tl images (early, intermediate and delayed) using the dual-isotope protocol. A polar map was created and defect scores (extent and severity) were determined by comparison with normal control data. Fluorodeoxyglucose positron emission tomography was also performed in 16 patients with old myocardial infarction. In patients with old infarction, the severity score decreased significantly from the early to the intermediate images, and decreased further on the delayed images. In patients with acute infarction, the score increased from the early to the intermediate images, but not on the delayed images. Regional uptake on the delayed images showed a better correlation with the fluorodeoxyglucose images than that on the early images. Redistribution on the delayed images was exclusively observed in the myocardial segments with less uptake than that estimated by fluorodeoxyglucose. In conclusion, addition of delayed 201Tl imaging to the dual-isotope protocol could improve the sensitivity for detecting myocardial viability.

Aged↗

Real time visualization of 13N-translocation in rice under different environmental conditions using positron emitting Ttacer imaging system.

The ammonium ion is an indispensable nitrogen source for crops, especially paddy rice (Oryza sativa L. cv Nipponbare). Until now, it has been impossible to measure ammonium uptake and nitrogen movement in plants in real time. Using the new technologies of PETIS (positron emitting tracer imaging system) and PMPS (positron multi-probe system), we were able to visualize the real time translocation of nitrogen and water in rice plants. We used positron-emitting 13N-labeled ammonium (13NH4+) and 15O-water to monitor the movement. In plants cultured under normal conditions, 13NH4+ supplied to roots was taken up, and a 13N signal was detected at the discrimination center, the basal part of the shoots, within 2 minutes. This rapid translocation of (13)N was almost completely inhibited by a glutamine synthetase inhibitor, methionine sulfoximine. In general, nitrogen deficiency enhanced 13N translocation to the discrimination center. In the dark, 13N translocation to the discrimination center was suppressed to 40% of control levels, whereas 15O-water flow from the root to the discrimination center stopped completely in the dark. In abscisic acid-treated rice, 13N translocation to the discrimination center was doubled, whereas translocation to leaves decreased to 40% of control levels. Pretreatment with NO3- for 36 hours increased 13N translocation from the roots to the discrimination center to 5 times of control levels. These results suggest that ammonium assimilation (from the roots to the discrimination center) depends passively on water flow, but actively on NH4+-transporter(s) or glutamine synthetase(s).

Biological Transport↗

Epstein-Barr virus-associated gastric carcinoma in Japanese Brazilians and non-Japanese Brazilians in São Paulo.

The proportion of Epstein-Barr virus-associated gastric carcinoma (EBV-GC) was examined in 149 Japanese-Brazilian and 151 non-Japanese-Brazilian gastric-carcinoma cases using in situ hybridization (ISH) assay to detect EBV-encoded small RNA (EBER), and the results were compared with our referent Japanese data. We found that 4.7% of cases in Japanese Brazilians were EBER-positive. This frequency was slightly lower than that of the referent Japanese, among whom 6.2% of 2038 gastric-carcinoma cases were EBER-positive. On the other hand, the non-Japanese-Brazilian series showed a significantly higher proportion of EBV-GC (11.2%) than the referent group did (P = 0.01). Although EBV-GC was predominant in males among non-Japanese Brazilians (M / F = 3.6, P = 0.047), as was the case in Japanese (M / F = 2.7), Japanese Brazilians did not show such a male predominance. The sex-ratio difference between the Japanese Brazilians and Japanese was statistically significant (P = 0.005). In conclusion, the present study in Japanese Brazilians and Japanese yielded no evidence suggesting any change in the frequency of EBV-GC caused by migration, except the absence of male predominance, which was observed both in Japanese and non-Japanese Brazilians.

Adenocarcinoma↗

[Clinical evaluation of an immunochromatography test for rapid diagnosis of influenza].

We evaluated a rapid diagnostic kit that detects influenza type A and B viral antigens by immunochromatography, Quick Vue Influenza Test (Quidel Corp., San Diego, CA, USA), with 425 specimens collected from patients with influenza-like symptoms at three hospitals between January and March 2001. The specimens included 184 nasal aspirates, 140 nasal swabs, and 101 throat swabs. The test correctly identified 179 of the 204 culture positive specimens and 203 of the 221 culture negative specimens; the sensitivity and specificity compared with the culture were 87.7% and 91.9%, respectively. The sensitivity of the test was 92.6% (112/121) for nasal aspirates, 83.7% (41/49) for nasal swabs, and 76.5% (26/34) for throat swabs, which is similar to the results for conventional rapid enzyme immunoassay kits for influenza virus infection. The sensitivity and specificity of the QuickVue Influenza Test were equivalent to those of Flu OIA (BioStar, Inc., Boulder, CO, USA), with the agreement of 84.2%. Although the QuickVue Influenza Test does not differentiate between influenza A and B viruses, the easy-to-use kit detects both types in the physician's office, allowing physicians to make a decision on prescription of neuraminidase inhibitor therapy during the initial visit.

Evaluation Studies as Topic↗

[Evaluation of immunochromatography method for rapid detection of influenza A and B viruses].

We have evaluated a new rapid detection kit for influenza A and B viruses, known as the QuickVue Influenza test (Quidel Coporation, USA); which is based on immunochromatography using virus isolates and clinical specimens. Twelve strains of influenza A and B were tested for evaluate the reactivity and detection limits of this test. The QuickVue Influenza test showed a positive result for all twelve strains of influenza virus and a negative result for fourteen different kinds of other respiratory viruses. The detection limits for six strains were 5 to 30 pfu/ml for a cell culture, 1.0 x 10(3) to 6.0 x 10(4) pfu/ml for 1st PCR, 1 to 50 pfu/ml for nested PCR, 3.0 x 10(5) to 6.0 x 10(5) pfu/ml for the QuickVue Influenza test, 1.5 x 10(5) to 1.0 x 10(6) pfu/ml for the Directigen Flu A, and 7.5 x 10(5) to 5.0 x 10(6) pfu/ml for the FLU OIA. Furthermore, the QuickVue Influenza test were clinically evaluated using 92 throat swab specimens collected from patients with influenza-like illnesses. By cell culture, influenza viruses were detected in 49 of the 92 specimens (AH1N1: 20, AH3N2: 7, B: 22); the titers of the influenza viruses were between 2.5 pfu/ml and 7.0 x 10(5) pfu/ml. Compared to cell culture, the QuickVue Influenza test showed a sensitivity of 75.5%, a specificity of 93.0%, a positive predictive value of 92.5%, a negative predictive value of 76.9%, and an efficiency value of 83.7%. On the other hand, influenza viruses were detected in 54 of the 92 specimens (AH1N1: 19, AH 3N2: 10, B: 25) by RT-PCR. Compared to RT-PCR, the QuickVue Influenza test showed a sensitivity of 72.2%, a specificity of 97.4%, a positive predictive value of 97.5%, a negative predictive value of 71.2%, and an efficiency value of 82.6%. Overall, only one throat swab specimen produced a false positive result using the QuickVue Influenza test; thus, this test appears to have a high specificity. We conclude that the QuickVue Influenza test is a simple one-step test with a sensitivity and specificity equivalent to those of other conventional diagnostic kits. The test is useful and suitable for the diagnosis of influenza and for identifying influenza patients requiring antiviral therapy.

Influenza A virus↗

Expression of ubiquitin gene in Microsporum canis and Trichophyton mentagrophytes cultured with fluconazole.

The expression of the ubiquitin (Ub) gene in dermatophytes was examined for its relation to resistance against the antifungal drug fluconazole. The nucleotide sequences and the deduced amino acid sequences of the Ub gene in Microsporum canis were proven to be 99% similar to those of the Ub gene in Trichophyton mentagrophytes. Expression of mRNA of Ub in M. canis and T. mentagrophytes was enhanced when the fungi were cultured with fluconazole. The antifungal activity of fluconazole against these dermatophytes was increased in the presence of Ub proteasome inhibitor.

Amino Acid Sequence↗

Influenza A virus can undergo multiple cycles of replication without M2 ion channel activity.

Ion channel proteins are common constituents of cells and have even been identified in some viruses. For example, the M2 protein of influenza A virus has proton ion channel activity that is thought to play an important role in viral replication. Because direct support for this function is lacking, we attempted to generate viruses with defective M2 ion channel activity. Unexpectedly, mutants with apparent loss of M2 ion channel activity by an in vitro assay replicated as efficiently as the wild-type virus in cell culture. We also generated a chimeric mutant containing an M2 protein whose transmembrane domain was replaced with that from the hemagglutinin glycoprotein. This virus replicated reasonably well in cell culture but showed no growth in mice. Finally, a mutant lacking both the transmembrane and cytoplasmic domains of M2 protein grew poorly in cell culture and showed no growth in mice. Thus, influenza A virus can undergo multiple cycles of replication without the M2 transmembrane domain responsible for ion channel activity, although this activity promotes efficient viral replication.

Animals↗

Ebola virus glycoprotein: proteolytic processing, acylation, cell tropism, and detection of neutralizing antibodies.

Using the vesicular stomatitis virus (VSV) pseudotype system, we studied the functional properties of the Ebola virus glycoprotein (GP). Amino acid substitutions at the GP cleavage site, which reduce glycoprotein cleavability and viral infectivity in some viruses, did not appreciably change the infectivity of VSV pseudotyped with GP. Likewise, removal of two acylated cysteine residues in the transmembrane region of GP showed no discernible effects on infectivity. Although most filoviruses are believed to target endothelial cells and hepatocytes preferentially, the GP-carrying VSV showed greater affinity for epithelial cells than for either of these cell types, indicating that Ebola virus GP does not necessarily have strong tropism toward endothelial cells and hepatocytes. Finally, when it was used to screen for neutralizing antibodies against Ebola virus GP, the VSV pseudotype system allowed us to detect strain-specific neutralizing activity that was inhibited by secretory GP (SGP). This finding provides evidence of shared neutralizing epitopes on GP and SGP molecules and indicates the potential of SGP to serve as a decoy for neutralizing antibodies.

Acylation↗