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T Ando

Publications and source records attributed to T Ando.

At least 181 records · Page 10Linked to original sources
PubMed1999

Identification of a distinct common strain of "Norwalk-like viruses" having a global distribution.

"Norwalk-like viruses" (NLVs) are the most common cause of outbreaks of nonbacterial gastroenteritis. During molecular surveillance of NLV strains from 152 outbreaks of gastroenteritis that occurred in the US between August 1993 and July 1997, we identified an NLV strain that predominated during the 1995-1996 season. The "95/96-US" strain caused 60 outbreaks in geographically distant locations within the US and was identified, by sequence comparisons, in an additional 7 countries on 5 continents during the same period. This is the first demonstration linking a single NLV strain globally and suggests that the circulation of these strains might involve patterns of transmission not previously considered. The diagnostic techniques are now available to establish a global network for surveillance of NLV strains that would highlight the importance of NLVs worldwide and allow molecular identification of common strains having a global distribution so as to consider interventions for their control.

Caliciviridae Infections↗
PubMed1999

An outbreak of acute gastroenteritis in a geriatric long-term-care facility: combined application of epidemiological and molecular diagnostic methods.

OBJECTIVE: To assess possible transmission modes of, and risk factors for, gastroenteritis associated with Norwalk-like viruses (NLVs) in a geriatric long-term-care facility. METHODS: During a prolonged outbreak of acute gastroenteritis, epidemiological data on illness among residents and employees were collected in conjunction with stool, vomitus, and environmental specimens for viral testing. NLVs were identified by electron microscopy in stool and vomitus specimens, and further characterized by reverse-transcriptase polymerase chain reaction and nucleotide sequencing. Potential risk factors were examined through medical-record review, personal interview, and a self-administered questionnaire sent to all employees. RESULTS: During the outbreak period, 52 (57%) of 91 residents and 34 (35%) of 90 employees developed acute gastroenteritis. Four case-residents were hospitalized; three residents died at the facility shortly after onset of illness. A point source was not identified; no association between food or water consumption and gastroenteritis was identified. A single NLV strain genetically related to Toronto virus was the only pathogen identified. Residents were at significantly higher risk of gastroenteritis if they were physically debilitated (relative risk [RR], 3.5; 95% confidence interval [CI95], 1.0-12.9), as were employees exposed to residents with acute gastroenteritis (RR, 2.6; CI95, 1.1-6.5) or ill household members (RR, 2.3; CI95, 1.4-3.6). Adherence to infection control measures among the nursing staff may have reduced the risk of gastroenteritis, but the reduction did not reach statistical significance. CONCLUSIONS: In the absence of evidence for food-borne or waterborne transmission, NLVs likely spread among residents and employees of a long-term-care facility through person-to-person or airborne droplet transmission. Rapid notification of local health officials, collection of clinical specimens, and institution of infection control measures are necessary if viral gastroenteritis transmission is to be limited in institutional settings.

Adult↗
PubMed1999

Age at time of hepatitis Be antibody seroconversion in childhood chronic hepatitis B infection and mutant viral strain detection rates.

BACKGROUND: Investigations of adult patients have demonstrated that with seroconversion, changes occur from wild-type strains of the infecting virus to mutant strains. However, to date, there have been few reports and insufficient investigation of this issue in children. METHODS: The presence or absence of nucleotide base and amino acid sequence mutations in a portion of the X region containing the core promoter region, the pre-C region, and the C region of HBV genomic DNA were investigated using a polymerase chain reaction-direct sequencing method on serum samples collected from 14 children who were hepatitis Be antibody (HBeAb)-positive carriers. Samples from three children who were HBe antigen (HBeAg)-positive carriers served as the control subjects. RESULTS: When patients were grouped based on whether they had had documented seroconversion before age 6 or at age 6 or older, differences in mutant viral detection rates involving the core promoter region and the pre-C region were apparent. Specifically, a mutant strain showing a G-to-A substitution at nucleotide 83 in the pre-C region, or a mutant strain showing an A-to-T substitution at nucleotide 1762 and a G-to-A substitution at nucleotide 1764, was detected in only two of eight cases (25%) from the HBeAb-positive carriers with documented seroconversion before age 6. In contrast, these findings were present in six of six patients (100%) with documented seroconversion at age 6 or older. CONCLUSIONS: The results of the present study suggest that the mechanism of onset of HBeAb seroconversion differs between children aged less than 6 years and those who are aged 6 or more.

Adolescent↗
PubMed1999

Clinicopathological features of superficial depressed-type colorectal neoplastic lesions.

OBJECTIVE: We performed this study to analyze the endoscopic findings, dissecting microscopic features, and p53 immunostaining in superficial depressed-type (depressed) colorectal neoplastic lesions. METHODS: Dissecting stereomicroscopy was used to ascertain the size and pit pattern of lesions removed by endoscopic snare polypectomy. Immunohistochemical staining of p53 was performed with an antigen retrieval system using a monoclonal antibody to p53. RESULTS: All depressed neoplastic lesions (submucosal carcinoma, n = 6; high-grade dysplasia, n = 14; and adenoma, n = 30) were small (< 1 cm in diameter) and were detected as a depression with or without a marginal elevation on colonoscopic examination. In the dissecting microscopic study, submucosal carcinomas and lesions of high-grade dysplasia almost exclusively showed irregular small pits, with the exception of four malignant lesions with moderate submucosal invasion in which the pit structure was absent. In contrast, adenomas had either regular small (29/30 lesions) or oval pits (1/30 lesions). Rates of p53 positivity were 100%, 64%, and 7% in depressed submucosal carcinomas, lesions of high-grade dysplasia, and adenomas, respectively, thus the prevalence of p53 positivity was significantly higher in the former two groups than in the adenoma group. CONCLUSIONS: The high frequency of invasive carcinoma and high-grade dysplasia found in depressed colorectal neoplastic tumors, despite their small size, indicates that these lesions may be a subtype of colorectal tumor with more aggressive malignant potential at an earlier stage.

Adenoma↗
PubMed1999

HP0333, a member of the dprA family, is involved in natural transformation in Helicobacter pylori.

Helicobacter pylori is naturally competent for DNA transformation, but the mechanism by which transformation occurs is not known. For Haemophilus influenzae, dprA is required for transformation by chromosomal but not plasmid DNA, and the complete genomic sequence of H. pylori 26695 revealed a dprA homolog (HP0333). Examination of genetic databases indicates that DprA homologs are present in a wide variety of bacterial species. To examine whether HP0333 has a function similar to dprA of H. influenzae, HP0333, present in each of 11 strains studied, was disrupted in two H. pylori isolates. For both mutants, the frequency of transformation by H. pylori chromosomal DNA was markedly reduced, but not eliminated, compared to their wild-type parental strains. Mutation of HP0333 also resulted in a marked decrease in transformation frequency by a shuttle plasmid (pHP1), which differs from the phenotype described in H. influenzae. Complementation of the mutant with HP0333 inserted in trans in the chromosomal ureAB locus completely restored the frequency of transformation to that of the wild-type strain. Thus, while dprA is required for high-frequency transformation, transformation also may occur independently of DprA. The presence of DprA homologs in bacteria known not to be naturally competent suggests a broad function in DNA processing.

Amino Acid Sequence↗
PubMed1999

Prevalence of GB virus C/hepatitis G virus ribonucleic acid and anti-hepatitis G virus-E2 antibodies among Japanese children with histories of transfusions or with liver diseases.

To clarify the prevalence of Japanese children thought to be at a risk for infection with GB virus-C (GBV-C)/hepatitis G virus (HGV), we investigated the detection rates of serum GBV-C/ HGV ribonucleic acid (RNA) by reverse transcription-seminested PCR and serum anti-HGV-E2 antibody by ELISA in 162 children with histories of blood or plasma product transfusions or with liver diseases and performed phylogenetic analysis of the 5' noncoding region sequences of GBV-C/HGV genomes. Children with histories of transfusions were divided into those who had been treated with antineoplastic agents for malignant diseases (malignant group) and those who had received transfusions for nonmalignant diseases (nonmalignant group). Children with liver diseases were divided into hepatitis B (HBV), hepatitis C (HCV), and non-A-C hepatitis groups. We detected GBV-C/ HGV RNA in 11 of 33 (33.3%) and anti-HGV-E2 in 1 of 27 (3.7%) children in the malignant group and in 3 of 56 (5.4%) and 1 of 53 (1.9%) children, respectively, in the nonmalignant group. Neither GBV-C/HGV RNA nor anti-HGV-E2 was detected in the HBV and non-A-C hepatitis groups. GBV-C/HGV RNA and anti-HGV-E2 were detected in 7 of 23 (30.4%) and in 1 of 18 (5.6%) children, respectively, in the HCV group. All children positive for either GBV-C/HGV RNA or anti-HGV-E2, except one whose route of GBV-C/HGV infection suggested mother-to-infant transmission, had histories of transfusions. The phylogenetic analysis showed that all isolates in this study were divisible into three groups and that most of them were clustered into group 3 (Asian group).

Adolescent↗
PubMed1999

DNA cleavage activities of (-)-epigallocatechin, (-)-epicatechin, (+)-catechin, and (-)-epigallocatechin gallate with various kinds of metal ions.

The DNA cleavage activities of (+)-catechin (C), (-)-epicatechin (EC), (-)-epigallocatechin (EGC), and (-)-epigallocatechin gallate (EGCg) were examined with 16 different metal ions. Cu(2+) with all the catechins facilitated DNA cleavage, while Ag+ with EGC and EC showed a strong repressive effect. The other metal ions examined showed little effect.

Animals↗
PubMed1999

Buccal mucosa ridging and tongue indentation: incidence and associated factors.

Buccal mucosa ridging and tongue indentation have been considered as one of the visible and reliable signs of bruxism. However, there have not been any reports justifying this relationship scientifically. Moreover, there have not been any studies reporting specific procedures to assess them. Thus, the purpose of the present study was to determine the clinical incidence of buccal mucosa ridging and tongue indentation and assess the possible relationship between certain factors that can influence their occurrence. A total of 244 (178 males and 66 females) dentulous adults from 20 to 59 years of age, who were employees at the Bank of Yokohama, were randomly selected. At first, the buccal mucosa ridging and tongue indentation were classified into three groups based in their intensity: none, mild, and severe. The incidence of both conditions in the different age groups, as well as the incidence by gender was evaluated. Furthermore, the possible relationships between buccal mucosa ridging and tongue indentation and age, gender, clenching awareness, grinding awareness, headache, neck stiffness, vertical dimension, temporomandibular joint (TMJ) pain to palpation, masticatory muscle tenderness to palpation, and the presence of premature contacts were evaluated using the chi-square test. A positive relationship was found between the occurrence of buccal mucosa ridging and tongue indentation and gender (p < 0.01); both conditions were observed more frequently in females than in males. A positive relationship was also found to age; the group between 20-29 years old showed the highest incidence. The vertical dimension had a positive relationship with the occurrence of both buccal mucosa ridging and tongue indentation. Other factors evaluated did not show any correlation.

Adult↗
PubMed1999

Circadian rhythm in hypotensive effect of sodium nitroprusside in rats and its relevance to sympathetic nervous activity.

Circadian rhythmicity in the hypotensive effects of sodium nitroprusside (SNP) was determined to characterize the rhythmicity in hypotension mediated by nitric oxide (NO) donor in rats. When SNP was infused for 90 seconds every hour for 48 hours and the mean blood pressure was determined automatically by telemetry under light-dark conditions (LD), the degree of SNP-induced hypotension was shown to be minimal at the onset of the dark phase and to have marked circadian rhythmicity. The possible relationship between the circadian rhythm of the sympathetic nervous system (SNS) activity and SNP-induced hypotension was examined under LD conditions. The SNS activity assessed by blood pressure beat-to-beat variability analysis using the maximum entropy method (MEM) was higher at the preinfusion time at the onset of the dark phase than during the middle of the light phase. In addition, pretreatment with an alpha-blocker, phentolamine, followed by SNP infusion at the onset of the dark phase restored the SNP-induced hypotension and consequently dampened the daily variation in the degree of SNP-induced hypotension. The circadian rhythmicity determined by MEM was weakened, but persisted, in constant dark conditions (DD), suggesting partial involvement of endogenously driven circadian rhythms. In conclusion, the hypotensive effect of hourly infused SNP in rats was decreased in the dark phase in LD, especially at the onset of the dark phase, and clearly showed circadian rhythmicity in both LD and DD. The SNP-induced hypotension may be affected by rapid activation of the SNS at the onset of the dark phase in LD, and regulation of the circadian rhythm in SNP-induced hypotension in rats may be affected by both exogenous light stimuli and the endogenous biological clock.

Adrenergic alpha-Antagonists↗
PubMed1999

[The role of angioscopy and intravascular ultrasound imaging in acute coronary syndrome].

Evaluation of the severity of coronary atherosclerosis by intracoronary imaging may be closely relevant with the prevention and treatment of acute coronary syndromes. Coronary angioscopy as one of the innovative methods of imaging and intravascular ultrasound makes the insight visualization of coronary vessel wall and histological recognition possible recently. Yellow plaques rich in lipid materials and covered by thin membrane are more often ruptured than white ones to cause acute coronary syndromes. In patients with unstable angina and acute myocardial infarction, the yellow plaques with intimal flaps and irregularities are frequently observed by angioscopy. Angioscopy is also the most powerful tool to detect intracoronary thrombus. In patients with acute myocardial infarction, thrombosis occludes vessel lumen totally, but it does not in the unstable angina cases. After thrombolytic therapy, the white thrombus is more often observed than the red one. Although angioscopy is superior to any other examination in diagnosing thrombosis, some complicated plaques are difficult to distinguish from thrombus. In addition to measurements of vascular dimension and plaque volume, histological diagnosis of plaque is being made by intravascular ultrasound. More precise evaluation of plaque histology may be a clue to predict the occurrence of acute coronary syndrome. Intravascular ultrasound is not so useful enough to diagnose thrombosis. In conclusion, the applications of intravascular imaging technologies, such as angioscopy and intravascular ultrasound, may play a critical role in the diagnosis and treatment of acute coronary syndromes.

Angioscopy↗
PubMed1999

[Interstitial pneumonia, pulmonary thrombotic microangiopathy, and hyperimmunoglobulinemia associated with Basedow's disease].

A 44-year-old man with a history of Basedow's disease complained of dry cough and lymphadenopathy. Polyclonal hypergammaglobulinemia (IgG level: 5,839 mg/dl) was present, and the patient's serum was positive for lupus anticoagulant. Chest radiography disclosed irregular thickening of bronchovascular bundles, centrilobular granular and branching opacities, and small cystic changes in both lung fields. Examination of a thoracoscopic biopsy specimen revealed fibrous thickening of the pleura, interlobular septum, and peribronchiolar/perivascular connective tissue, with mild round-cell infiltration. Lymphoid follicle formation and pulmonary thrombotic microangiopathy were also observed. Corticosteroid therapy was ineffective for hypergammaglobulinemia and diffuse opacities disclosed by chest computed tomographic scans. This case differed from multicentric Castleman's disease with respect to the pathological findings of a lymph nodes biopsy, and also was not consistent with any known collagen vascular disease, (e.g., Sjögren's syndrome). We suspect this case may be representative of a new form of collagen vascular disease.

Adult↗
PubMed1999

Comparison between pre- and posttreatment clinical and renal biopsies in children receiving low dose ciclosporine-A for 2 years for steroid-dependent nephrotic syndrome.

BACKGROUND: The dose of ciclosporine-A (CSA) for long-term treatment of nephrotic syndrome remains unclear due to the chronic nephrotoxicity of CSA. PATIENTS AND METHODS: We examined 14 children with steroid-dependent nephrotic syndrome (SDNS) who showed signs of steroid toxicity and did not respond to cyclophosphamide. CSA was started at a dose between 2.0 and 3.3 mg/kg/day and the CSA dosage was decreased to between 1.6 and 3.1 mg/kg/day 4 months after the initiation of CSA therapy to maintain 40 to 70 ng/ml in the whole blood trough level. RESULTS: Renal histology before CSA therapy showed minimal changes in all patients. It was possible to discontinue corticosteroid therapy within 3 to 4 months in all patients. The SD score for height significantly improved during CSA therapy. The incidence of CSA side-effects in our patients was lower than previously reported. Post-therapy biopsies after 24 months of CSA treatment showed mild tubular atrophy accompanying stripped interstitial fibrosis in only 1 patient (7%), and positive findings of global sclerosed glomeruli in 2 patients. CONCLUSION: Long-term CSA therapy in low doses was effective for patients with SDNS and demonstrated a low incidence of CSA side-effects including nephrotoxicity.

Child↗
PubMed1999

Role of an ATP-sensitive potassium channel opener, YM934, in mitochondrial energy production in ischemic/reperfused heart.

We examined a possible mechanism of action of an ATP-sensitive potassium (K(ATP)) channel opener, YM934, for the improvement of energy metabolism in hearts subjected to 35-min ischemia and 60-min reperfusion. The treatment with 30 nM YM934 for the final 15 min of preischemia enhanced postischemic recovery of left ventricular developed pressure, attenuated the postischemic rise in left ventricular end-diastolic pressure, and suppressed the release of creatine kinase and ATP metabolites during reperfusion. The treatment also restored myocardial ATP and creatine phosphate contents and attenuated the decrease in mitochondrial oxygen consumption rate during reperfusion. The higher mitochondrial function was also seen in YM934-treated hearts at the end of ischemia. In another set of experiments, myocardial skinned bundles were incubated for 30 min under hypoxic conditions in the presence and absence of YM934, and then mitochondrial oxygen consumption rate was determined. Hypoxia decreased the mitochondrial oxygen consumption rate of skinned bundles to approximately 40% of the prehypoxic value. In contrast, the treatment of skinned bundles with 30 nM YM934 preserved the mitochondrial oxygen consumption rate during hypoxia. The effect of YM934 on the hypoxic skinned bundles was abolished by combined treatment with either the K(ATP) channel blocker glyburide or the mitochondrial K(ATP) channel blocker 5-hydroxydecanoate in a concentration-dependent manner. The results suggest that YM934 is capable of attenuating ischemia/reperfusion injury of isolated perfused hearts due to preservation of mitochondrial function during ischemia, probably through opening of mitochondrial K(ATP) channels.

Adenosine Triphosphate↗
PubMed1998

PCR on cerebrospinal fluid to show influenza-associated acute encephalopathy or encephalitis.

BACKGROUND: Except for Reye's syndrome, influenza-associated acute encephalopathy or encephalitis is not universally recognised. We did a multicentre study of laboratory and clinical data for patients with influenza-associated acute encephalopathy or encephalitis. METHODS: In Nagoya, Japan, ten patients with acute encephalopathy or encephalitis associated with influenza-like illness were admitted to our hospitals between April, 1996, and March, 1997. We collected clinical, laboratory and serological data and assessed cerebrospinal fluid samples by PCR for influenza A and B. FINDINGS: Seven patients, aged 22 months to 4 years, had evidence of recent influenza infection, six with type-A/Hong Kong (H3N2) and one with type B. The first sign in the central nervous system appeared within 2 days of fever in all but one patient. The first sign of involvement of the central nervous system was generalised convulsions in all patients. Two patients died, one had sequelae, and four survived without sequelae. PCR for influenza type A was positive for five patients. INTERPRETATION: The results of PCR suggest that at least part of the influenza type A genome existed in the central nervous system. Influenza-associated acute encephalopathy or encephalitis in young children deserves wider recognition.

Acute Disease↗