PubMed Health⌕ Search

Biomedical subjects

T Tsuda

Publications and source records attributed to T Tsuda.

At least 19 recordsLinked to original sources

Genetic characterization of Batai virus indicates a genomic reassortment between orthobunyaviruses in nature.

Two viruses were isolated from bovine blood in the southernmost part of Japan in 1994 and 2001, respectively. Genetic analyses showed that the viruses were Batai virus of the genus Orthobunyavirus of the family Bunyaviridae. The sequencing of three genomic RNA segments of the Japanese and Malaysian Batai virus strains revealed that the M RNA segment of Batai virus had high sequence identity with that of Ngari virus. Our results indicate that Ngari virus is a genetic reassortant with S and L RNA segments from Bunyamwera virus and an M RNA segment from Batai virus.

Animals↗

Morphology of the enteric nervous system in the hindgut of an infant with cloacal exstrophy.

The authors describe the morphology of the enteric nervous system in the hindgut of an infant with cloacal exstrophy. Cloacal exstrophy was diagnosed at 32 weeks' gestation using prenatal ultrasonography. The baby was delivered at 34 weeks' gestation and underwent a separation of the cecum from bladder halves, reapproximation of hemibladders, closure of the omphalocele and pubic symphysis, and a distal colostomy. Intestinal wall specimens were obtained at colostomy from the distal end of the rudimentary hindgut. Serial frozen sections were prepared for histochemical acetylcholinesterase staining. Histological investigations demonstrated a strikingly crowded, immature enteric ganglia and prominent bundles of wandering cholinergic nerves. These findings suggest the unique pathology of the enteric nervous system development in cloacal exstrophy, in which the rudimentary hindgut behaves as a blind alley of the migratory pathway for neural crest-derived cells during embryogenesis. Histological examinations of the hindgut enteric nervous system in cloacal exstrophy may be beneficial for evaluating the postnatal development of the distal colon which might be utilized for a pull-through procedure.

Bladder Exstrophy↗

A clinical analysis of prognostic parameters of survival in children with congenital diaphragmatic hernia.

BACKGROUND: Congenital diaphragmatic hernia (CDH) still has a high mortality because of accompanying lung hypoplasia and persistent pulmonary hypertension. Although prognostic parameters based on perinatal measurements have been proposed, our ability to accurately predict the surgical results remains insufficient. METHODS: We treated 55 infants with CDH from 1981 to 2004. Among them, 46 patients presented respiratory distress within the first 24 hours of life. Results of surgical treatment in the 46 infants were retrospectively correlated with gender, birth weight, gestational age at diagnosis, laterality, cardiac anomalies, diaphragmatic defect area, contents of herniated viscera, and the great vessel diameters measured by echocardiography. RESULTS: Out of 46 CDH neonates, 27 (58.7 %) survived and 19 (41.3 %) died aged 3 to 17 days. Non survivors had a significantly larger diaphragmatic defect and more frequent liver herniation. Out of possible predictive parameters studied, an index of the main pulmonary artery (cross-sectional area/diaphragmatic defect area ratio) most closely correlated with the surgical outcomes. CONCLUSIONS: The postoperative prognosis of CDH infants does not depend only on pulmonary hypoplasia, but also on other factors including the magnitude of abdominal visceral herniation. In this series of patients, the most reliable prognostic predictor was a clinical index reflecting the degree of both pulmonary hypoplasia and diaphragmatic maldevelopment.

Female↗

Isolation of bovine arboviruses from Culicoides biting midges (Diptera: Ceratopogonidae) in southern Japan: 1985--2002.

In 1985--2002, surveillance for bovine arboviruses was conducted in Kagoshima, located in the most southern part of the main islands of Japan and known to be an area where bovine arboviral diseases have frequently been epidemic. Culicoides biting midges were collected in a cowshed by light traps. A total of 456,300 Culicoides biting midges representing 13 species were collected, and a portion of each pool of midges were tested for virus isolation. Overall, 85 isolates of six different viruses were obtained from the collected midges. The isolated viruses included two Orthobunyaviruses, Akabane and Aino viruses; three Orbiviruses, Chuzan, D'Aguliar, and Ibaraki viruses; and one unclassified virus, a bunyavirus-like virus. The viruses were most frequently isolated from Culicoides oxystoma Kieffer (85.9% of 85 isolates). Isolations of all viruses except for the bunyavirus-like virus were made from this species. Our data indicated that C. oxystoma is a potential vector for bovine arboviruses in southern Japan.

Animals↗

The resurgence of Shamonda virus, an African Simbu group virus of the genus Orthobunyavirus, in Japan.

Six virus isolations were made from Culicoides biting midges and blood samples of sentinel cattle in Kagoshima and Miyazaki Prefectures, the southern part of Japan, in 2002. Serological and genetical tests identified these viruses as isolates of Shamonda virus (SHAV), which belongs to the Simbu group of the genus Orthobunyavirus of the family Bunyaviridae. Initially, SHAV was isolated from cattle and Culicoides biting midges in Nigeria in the 1960s, and its presence has not been reported until this study. The present results indicate a wider distribution of SHAV than previously assumed.

Animals↗

The emergence in Japan of Sathuperi virus, a tropical Simbu serogroup virus of the genus Orthobunyavirus.

In 1999, two viruses were isolated from blood samples of sentinel cattle in the Western part of Japan. The physiochemical and morphological properties of these viruses indicated that they belonged to the family Bunyaviridae. Sequence analysis of the S segment indicates that the two viruses are closely related to Sathuperi virus (SATV). The N-terminal 168 amino acid of the G2 protein of the M segment was highly homologous with that of SATV (98.2%). Given these results, we conclude that the newly isolated viruses are closest to SATV, which was initially isolated in India and Nigeria over 30 years ago.

Amino Acid Sequence↗

Effects of pre-exercise listening to slow and fast rhythm music on supramaximal cycle performance and selected metabolic variables.

We examined the effect of listening to two different types of music (with slow and fast rhythm), prior to supramaximal cycle exercise, on performance, heart rate, the concentration of lactate and ammonia in blood, and the concentration of catecholamines in plasma. Six male students participated in this study. After listening to slow rhythm or fast rhythm music for 20 min, the subjects performed supramaximal exercise for 45 s using a cycle ergometer. Listening to slow and fast rhythm music prior to supramaximal exercise did not significantly affect the mean power output. The plasma norepinephrine concentration immediately before the end of listening to slow rhythm music was significantly lower than before listening (p < 0.05). The plasma epinephrine concentration immediately before the end of listening to fast rhythm music was significantly higher than before listening (p < 0.05). The type of music had no effect on blood lactate and ammonia levels or on plasma catecholamine levels following exercise. In conclusion, listening to slow rhythm music decreases the plasma norepinephrine level, and listening to fast rhythm music increases the plasma epinephrine level. The type of music has no impact on power output during exercise.

Adult↗

[Re-do coronary artery bypass grafting with the descending branch of the lateral femoral circumflex artery in a patient with chronic hemodialysis].

A 52-year-old man with hemodialysis had undergone coronary artery bypass grafting (CABG); left internal thoracic artery (LITA) to left anterior descending artery (LAD), right gastroepiploic artery (RGEA) to posterolateral branch (PL), saphenous vein graft (SVG) to diagonal artery (Dx) 5 years previously. After 3 years, angiography was performed due to recurrence of angina pectoris and revealed RGEA and SVG was totally occluded. Since repeated intervention was unsuccessful, reoperation was necessary. Therefore, we performed re-do CABG without cardiopulmonary bypass using lateral femoral circumflex artery (LFCA) as an arterial conduit for myocardial revascularization via the 6th left intercostal posterolateral thoracotomy. Postoperative angiography showed that the LFCA bypass graft was patent and supplied sufficient blood to anastomosed vessel. The patient has had no angina pectoris subsequently. We believe this procedure is useful for re-do myocardial revascularization, and LFCA deserves to be taken into account as an alternative graft in a patient with chronic hemodialysis.

Angina Pectoris↗

Serological and genetic characterization of newly isolated Peaton virus in Japan. Brief report.

The viruses were isolated from the blood of sentinel cattle and Culicoides biting midges in the Kyushu district, southwestern Japan, in 1999 and identified by neutralization tests as Peaton (PEA) viruses. Before this study, PEA virus had been isolated in Australia only. The nucleotide identity of the nucleocapsid (N) protein encoded by the S segment ranged from 91.1 to 91.6% between the Australian and Japanese strains. A phylogenetic analysis of the N protein sequence revealed that the PEA virus strains are closely related to Aino (AIN) virus and suggested reassortment events for PEA and AIN viruses.

Amino Acid Sequence↗

Inhibitory effect of M50054, a novel inhibitor of apoptosis, on anti-Fas-antibody-induced hepatitis and chemotherapy-induced alopecia.

M50054, 2,2'-methylenebis (1,3-cyclohexanedione), was identified as a novel inhibitor of apoptosis (programmed cell death) using an in vitro cell death assay system induced in human Fas-expressing WC8 cells by soluble human Fas ligand. Furthermore, M50054 inhibited the apoptotic cell death of U937, a human monocytic leukemic cell line, induced by anticancer agents such as etoposide; it was also confirmed that M50054 inhibited apoptotic features such as DNA fragmentation and phosphatidylserine exposure in these cells. These anti-apoptotic effects were attributable to inhibition of caspase-3 activation. Additionally, M50054 significantly inhibited anti-Fas-antibody-induced elevation of plasma alanine aminotransferase and aspartate aminotransferase. Alopecia (hair loss) symptoms were also significantly improved with topical treatment with M50054. In conclusion, M50054 inhibits apoptosis induced by a variety of stimuli via inhibition of caspase-3 activation, and may thus be effective for hepatitis and chemotherapy-induced alopecia.

Alopecia↗

Effect of trapidil on effector functions of monocytes related to atherosclerotic plaque.

The infiltration and activation of inflammatory cells play an important role in the formation and stability of coronary atherosclerotic plaque in patients with acute coronary syndrome. In this study, we evaluated the effect of trapidil, an anti-platelet agent, on atheroma-related functions of human T cells and monocytes. Trapidil and anti-CD154 (CD40 ligand) antibody inhibited the increase of procoagulant activity in the mixed lymphocyte reaction; trapidil also suppressed the induction of tissue factor, monocyte chemoattractant protein-1 (MCP-1) and matrix metalloproteinase-9 in the mixed lymphocyte reaction. Trapidil did not alter CD154 expression on isolated T cells, but it diminished CD40 expression on isolated monocytes and human monocytic leukemia THP-1 cells stimulated with interferon-gamma. Moreover, trapidil reduced MCP-1 production of isolated monocytes and THP-1 cells stimulated with interferon-gamma plus CD154-transfected cells. This effect was not seen with other tested anti-platelet agents and coronary vasodilators. In conclusion, trapidil directly acts on monocytes/macrophages to lower their susceptibility to CD154 on T cells.

Animals↗

The critical role of the stem region as a functional domain responsible for the oligomerization and Golgi localization of N-acetylglucosaminyltransferase V. The involvement of a domain homophilic interaction.

We demonstrated that a region in the stem of N-acetylglucosaminyltransferase V (GnT-V), a Golgi resident protein, is not required for enzyme activity but serves as functional domain, responsible for intracellular localization. Deletion of the domain led to complete retention of the kinetic properties but resulted in the cell surface localization of the enzyme as well as its efficient secretion into the medium. The lack of this domain concomitantly abolished the disulfide-mediated oligomerization of GnT-V, which appears to confer the Golgi retention. When the domain was inserted into the stem region of a cell surface-localized type II membrane protein, the resulting chimeric protein was substantially oligomerized and predominantly localized in the intracellular organelle. Furthermore, it was found that the presence of this domain is exclusively responsible for homo-oligomer formation. This homophilic interaction appears to involve a hydrophobic cluster of residues in the alpha-helix of the domain, as indicated by secondary structure predictions. These findings suggest that the domain specifically participates in the Golgi retention of GnT-V, probably via inducing homo-oligomer formation, and would also provide a possible mechanism for the oligomerization, which is critical for localization in the Golgi.

Animals↗

A case-control study of the relationships among silica exposure, gastric cancer, and esophageal cancer.

BACKGROUND: We examined the effect of silica exposure on gastric and esophageal cancer mortality using a cancer control series in a population setting. METHODS: Cases and controls were restricted to male subjects and were drawn from death certificates in the Tobi area of Japan. A control group was selected from a series of deaths due to colon cancer, and cancers of other organs. The Japanese death certificate system is comprehensive because all deaths must be reported to the local office and death certificates are written by medical doctors. Age and smoking habits adjusted the Mantel-Haenszel odds ratios were estimated. RESULTS: For gastric cancer, the age-, smoking-adjusted odds ratios were 1.22 (95% CI 0.74-2.01) for colon cancer and the other cancer control for silica exposure work, and 1. 36 (95% CI 0.76-2.43) for silicosis. For esophageal cancer, the age- and smoking-adjusted odds ratios were 1.53 (95% CI 0.59-3.96) for the cancer control for silica exposure, and 2.33 (95% CI 0.87-6.23) for silicosis, respectively. CONCLUSIONS: The results suggest that gastric and esophageal cancer were related to silica exposure and silicosis in the study area, although they did not reach a statistically significant level because of the small sample size. The estimated odds ratios were higher for esophageal cancer and silicotic patients.

Adult↗

Long-term implantation test and tumorigenicity of polyvinyl alcohol hydrogel plates.

Two types of flat plates made from a polyvinyl alcohol (PVA) hydrogel with a water content of 80 and 20 (PVA-H80, PVA-H20), 20 x 10 x 1 mm in size, were subcutaneously implanted into each of 50 young, male Wistar rats. As a control, a sham operation was done on another set of 50 rats (Sham Op group). The shape and transparency of the PVA hydrogel were unchanged for up to 24 months. Tumors arose in 14 rats from the PVA-H80 group. In the PVA-H20 group, tumors appeared in 15 rats. The average tumor latency was 598 +/- 109 days in the PVA-H80 and 637 +/- 94 days in the PVA-H20. There was no difference in tumor incidence between the PVA-H20 and PVA-H80 groups (p < 0.05). In the Sham Op group, no malignant tumors appeared. Histopathologically, the tumors induced by hydrogel plates were malignant tumors resembling fibrosarcoma or malignant fibrous histiocytoma. This indicates that PVA hydrogel implants also induce solid state carcinogenesis at a similarly high rate to medical grade hydrophobic material reported in a previous study.

Absorbable Implants↗