Search PubMed⌕ Search

Biomedical subjects

Y Wada

Publications and source records attributed to Y Wada.

At least 469 records · Page 26Linked to original sources

A novel developmental process of intestinal epithelial lesions in a calf infected with attaching and effacing Escherichia coli.

A comparative study on the adhesion of attaching and effacing Escherichia coli (AEEC) to the enterocytes between the colon of a calf and the jejunum of a piglet showed differences in the developmental process of attaching and effacing (AE) lesions. In the calf, pedestals consisted of fused microvilli, while in the piglet they developed from the apical epithelial cell membranes after effacing microvilli. Microvilli adjacent to the AEEC attachment site were atrophic in the calf, whereas they were elongated in the piglet. The production of AE lesions in the calf may be indicative of a novel developmental process with AEEC infection.

Animals↗

Apoptosis of enterocytes induced by inoculation of a strain of attaching and effacing Escherichia coli and verotoxin.

When verotoxin (VT)-producing attaching and effacing Escherichia coli (AEEC, serotype O5: H-) were inoculated perorally into 10-day-old rabbits, attaching of the E. coli to enterocytes and effecting of their microvillous portion were observed extensively from the ileum to the colon. Subsequent apoptotic changes of the infected enterocytes were demonstrated by the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL) reaction and electron microscopy. Apoptosis was also induced in cultured Vero cells by inoculation of VT extracted from the AEEC. This study clarified that VT-producing AEEC induce apoptosis of enterocytes, causing mucosal damage.

Animals↗

Soft-tissue balancing with pressure distribution during total knee arthroplasty.

We measured the pressure distribution across the tibiofemoral and patellofemoral joints during total knee arthroplasty (TKA) using Fuji pressure-sensitive film (Prescale) in 51 patients (63 joints) comparing the results with those in 21 patients in whom Prescale was not used. We classified the stress-distribution patterns in the tibiofemoral joints into four types: normal, varus-valgus instability, rotational malalignment, and a combination of instability and malrotation. The medial ligaments were then released according to the information obtained from these patterns. The conformity ratio of the contact area between repeated trials was 87.0%. Pressure distribution across the patellofemoral joints was also considered. There was a significant decrease in the mean valgus stress angle in the Prescale group compared with the control group (p < 0.01). Release of the lateral retinaculum according to the results showed no significant differences in subluxation of the patella between the released group and the group which did not appear to need this procedure.

Aged↗

Homology of E2 gene in 8 child-mother pairs infected with hepatitis C virus.

The frequency of genetic homology of hepatitis C virus (HCV) E2 gene in 8 child-mother pairs was investigated. The route of HCV infection of all children suggested mother-to-child infection by their past history. In this study, we analyzed at least 5 complementary DNA (cDNA) clones for each case. In 6 of the 8 (75%) child-mother pairs, for the region between hypervariable region (HVR)-1 and HVR-2, the similarity of the nucleotide sequence of all 5 cDNA clones between each child and the mother was higher than that between the child and the other children, the other mothers and the sequences from GenBank. One of the 8 (13%) child-mother pairs showed a great similarity in parts of all cDNA clones. This was also confirmed by phylogenetic analyses of the sequences of cDNA clones from families and that from GenBank. These results suggested that the homology search of nucleotide sequence of this region was useful to confirm mother-to-child transmission of HCV.

Amino Acid Sequence↗

Nonradioisotopic telomeric repeat amplification protocol (TRAP) using digoxigenin labeled probe.

We have attempted to detect telomerase activity by Southern blot analysis using a digoxigenin labeled probe (5'-(CCCTTA)6CCCTAA-3') Telomerase activity was detected in all cancer cell lines that were tested, and:the lower limit for detection was 10(3) cells. Although telomerase activity was detected in colon cancer tissues, it was not found in adenoma or normal tissues. Telomerase activity was completely abrogated by heat and RNase treatment of the CHAPS extract. Our results demonstrate that this nonradioisotopic assay is safe and reliable for detecting telomerase activity in cancer cell lines and biopsy samples.

Blotting, Southern↗

Mechanoreceptors of patellar tendon used for ACL reconstruction. Rabbit experiments.

In 17 Japanese white rabbits (weighing 2.6-3.7 kg), the anterior cruciate ligament of the right knee was resected and then reconstructed, using the lateral half of the patellar tendon. The contralateral side served as control. Rabbits were killed 10, 20, or 30 weeks postoperatively. Then the reconstructed ligament was harvested and stained, using a modified gold chloride method. Under the light microscope, sensory nerve endings in serial sections were counted after being morphologically identified. With respect to the number of Pacinian and Ruffini corpuscles, there were no significant differences between the reconstructed ligament and the control patellar tendon at any time after surgery.

Animals↗

Molecular cloning of the human UMP synthase gene and characterization of point mutations in two hereditary orotic aciduria families.

Uridine monophosphate (UMP) synthase is a bifunctional enzyme catalyzing the last two steps of de novo pyrimidine biosynthesis, orotate phosphoribosyltransferase (OPRT) and orotidine-5'-monophosphate decarboxylase (ODC). Loss of either enzymatic activity results in hereditary orotic aciduria, a rare autosomal recessive disorder characterized by retarded growth, anemia, and excessive urinary excretion of orotic acid. We have isolated the UMP synthase chromosomal gene from a lambdaEMBL-3 human genomic library and report a single-copy gene spanning approximately 15 kb. The UMP synthase genomic structure encodes six exons ranging in size from 115 bp to 672 bp, and all splicing junctions adhere to the canonical GT/AG rule. Cognate promoter elements implicated in glucocorticoid- and cAMP-mediated regulation as well as in liver-, myeloid-, and lymphocyte-specific expression are located within the 5' flanking sequence. Molecular investigation of UMP synthase deficiency in a Japanese orotic aciduria patient revealed mutations R96G (A-to-G transition; nt 286) and G429R (G-to-C transversion; nt 1285) in one allele and V109G (T-to-G transversion; nt 326) in the other allele. Expression of human UMP synthase cDNAs containing these mutations in pyrimidine auxotrophic Escherichia coli and in recombinant baculovirus-infected Sf21 cells demonstrates impaired activity presumably associated with the urinary orotic acid substrate accumulations observed in vivo. We further establish the identity of two polymorphisms, G213A (v = .26) and 440Gpoly (v = .27) located in exons 3 and 6, respectively, which did not significantly compromise either OPRT or ODC function.

Adult↗

[Topographic analysis of resting EEG and photic driving responses in patients with presenile Alzheimer's disease].

Topographic analysis of the resting EEG was performed in nine patients with presenile Alzheimer's disease(AD) and nine sex- and age-matched normal subjects. We also analyzed EEG activity recorded during photic stimulation(5, 10 and 15 Hz) to evaluate photic driving responses. The square root of absolute power was determined for each frequency band using a Fast Fourier Transform. Compared with the controls, the AD patients had increased delta and theta in the resting EEG mainly over the frontal regions. The patients also had reduced alpha and beta, and did not show posterior predominance of alpha activity. EEG analysis during photic stimulation showed that the patients had a reduction in photic driving responses, and significant topographic differences were found over the parieto-occipital regions. These findings provide further evidence that AD patients have background EEG slowing with a reduction in alpha and fast activity. They also suggest an impairment of visual functioning in AD.

Alzheimer Disease↗

[A randomized comparative study of surgical adjuvant chemotherapy using 5-fluorouracil and dl-leucovorin with CDDP 5-FU and dl-leucovorin for colorectal cancer].

A randomized comparative study of surgical adjuvant chemotherapy using dl-leucovorin (dl-LV) and 5-fluorouracil (5-FU) (FL-therapy) with CDDP, 5-FU, and dl-LV (PFL-therapy) was conducted. The following were the administration schedules: Arm A was 13 mg/m2 of CDDP, 300 mg/m2 of 5-FU, and 30 mg/body of dl-LV for 5 consecutive days and arm B was 300 mg/m2 of 5-FU and 30 mg/body of dl-LV for 5 consecutive days. Both regimens were followed by biweekly administration of the same dose of dl-LV and 5-FU in outpatients. Arm A was started at the 26th postoperative day and arm B at the 21st day on average. Some 26 cases composed of 11 cases of arm A and 15 cases of arm B completed the administration schedules. Only one case in arm A was complicated by local recurrence around 35 months after operation. Major toxicities were anorexia and neutropenia. Both toxicities were seen more in arm A than in arm B, showing complete recovery in all cases. These data suggest that PFL-therapy and FL-therapy seem to be possible and promising surgical adjuvant therapies for advanced colorectal carcinoma.

Adenocarcinoma↗

[A case of successfully treated fungal tricuspid infective endocarditis with repeated pulmonary embolism].

A case of successfully treated fungal tricuspid infective endocarditis with repeated pulmonary embolism is reported. A 60-year-old man had received along term intravenous hyperalimentation for the treatment of the complication after hepatopancreatoduodenectomy, associated with Candida sepsis. He was once discharged, successfully treated with antifungal agents. But he was readmitted to our hospital due to fever, cough and chest pain. Blood culture revealed Candida tropicalis. Pulmonary scintigraphy and angiography revealed multiple infarcts of the right lung, and echocardiography showed vegetation on the tricuspid valve. Because of exacerbation of shortness of breath, tricuspid valvuloplasty and thromboembolectomy in the pulmonary arteries was performed. Postoperative course was uneventful and he had a marked improvement of dyspnea after operation.

Candidiasis↗

[Diversion of the inferior vena cava into the left atrium after repair of atrial septal defect with partial anomalous pulmonary venous drainage].

An 11-year-old female had operative repair of atrial septal defect associated with partial anomalous pulmonary venous drainage by direct suture at 6-year-old. Postoperatively, cyanosis and nodal bradycardia were noted by physical exercise. During 5 years thereafter, the symptoms were gradually aggravated accompanying. Cardiac catheterization revealed diversion of the inferior vena cava into the left atrium. Oxygen sampling showed right to left shunt of 22% at the atrial level. At reoperation, orifice of the inferior vena cava into the right atrium became narrow 5 mm in diameter. After enlargement of the orifice, the atrial septum was created with a Gore-Tex patch to redirect the inferior vena cava to the right atrium. Post operative course was uneventful with disappearance of the cyanosis. The patient is up and well now 9 years after reoperation.

Child↗

Pharmacological profile of a novel synthetic inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A reductase.

Pharmacological properties of NK-104 ((+)-monocalcium bis¿(3R,5S,6E)-7-[2-cyclopropyl-4-(4-fluorophenyl)-3-quinolyl++ +]-3,5-dihydroxy-6- heptenoate¿, CAS 147526-32-7), a novel synthetic inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, were investigated. The kinetic study, using rat liver microsomal HMG-CoA reductase, revealed that NK-104 is a competitive inhibitor of HMG-CoA reductase with a Ki of 1.7 nmol/l. To examine the inhibitory effect on sterol synthesis in vivo, de novo synthesis of sterols from [14C]acetate 3 h after oral administration of NK-104 was measured in rats. NK-104 showed marked inhibition in liver (ED50 0.13 mg/kg) and in ileum (ED50 0.20 mg/kg), but much weaker in the other tissues. The inhibitory effect of NK-104 on liver sterol synthesis lasted over 6 h, while that of pravastatin and simvastatin disappeared 6 h after administration of the drugs twice the ED50s. Due to induction of HMG-CoA reductase, initial suppression of hepatic sterol synthesis by pravastatin and simvastatin was compensated, and the cumulative change in hepatic sterol synthesis during 12 h after drug administration was remarkably negative only with long-acting NK-104. Hypolipidemic effects of NK-104 (0.03, 0.1, 0.3 and 1 mg/kg p.o. for 2 weeks) were examined in beagle dogs. NK-104 reduced plasma total cholesterol dose-dependently (13.1, 18.5 and 20.2% at doses of 0.1, 0.3 and 1 mg/kg, respectively), and also plasma triglycerides by 0.1 mg/kg or more. Pravastatin (1 and 3 mg/kg) and simvastatin (3 mg/kg) lowered plasma total cholesterol (14.0, 15.4 and 17.4%, respectively), but did not significantly affect plasma triglyceride levels. These results indicate that NK-104 is a potent, liver-selective, long-acting HMG-CoA reductase inhibitor with a high cholesterol- and triglyceride-lowering potency.

Animals↗

[Acute lymphoblastic leukemia complicated by type C hepatitis during treatment and further by acute interstitial pneumonia due to sho-saiko-to in 7-year-old].

The patient was complicated by type C hepatitis considered dur to blood preparations during the treatment of acute lymphoblastic leukemia. On administration of Sho-saiko-to, the white blood cell count decreased. When the drug was administered again, interstitial pneumonia developed concurrently. The case is a 7-year-old boy. He is the youngest to suffer interstitial pneumonia due to Sho-saiko-to in Japan, showing the possibility that interstitial pneumonia occurs even in childhood. A study of the IgG subclass at the time of the development of interstitial pneumonia in the affected child showed an imbalance of the subclass, with an increase in the percentage of IgG1 and IgG3, and a decreased in the percentage of IgG2 and IgG4. With improvement in the symptoms thereafter, however, the IgG subclass normalized. Thus it is possible that the IgG subclass is concerned with the development of interstitial pneumonia in this case. So, making careful observations is needed in administering Sho saiko-to to children with type C hepatitis who use various immunosuppressants.

Child↗

A tumor preventive effect of dietary restriction is antagonized by a high housing temperature through deprivation of torpor.

Energy restriction (ER) has proven to be the only effective means of retarding aging in mice. The mechanisms of multiplicity of effects of ER on aging remain, however, fragmentary. ER induces daily torpor, the induction of which is reduced by increasing the ambient temperature to 30 degrees C. The effects of preventing hypothermia in ER animals were studied in terms of the expected consequences of ER on survival, disease pattern and a number of physiological parameters in autoimmune prone MRL/lpr mice and lymphoma prone C57BL, 6 mice. The results demonstrate that torpor plays a crucial role in the prevention of lymphoma development but does not have an affect on other aspects of ER, such as prevention of autoimmune diseases.

Aging↗