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Y Tanaka

Publications and source records attributed to Y Tanaka.

At least 145 records · Page 8Linked to original sources
PubMed2002

Monitoring cytomegalovirus infection by antigenemia assay and two distinct plasma real-time PCR methods after hematopoietic stem cell transplantation.

We compared a CMV virus load determined by real-time PCR with an antigenemia value to analyze the correlation between these two methods. We also compared the values for virus load determined by the two distinct real-time PCR methods, which amplify the US17 region and immediate-early (IE) gene of CMV, respectively, to evaluate the reliability of these methods. Two hundred and sixty-five samples were obtained weekly from 29 patients, who had engraftment after unrelated bone marrow transplantation or HLA-mismatched related blood stem cell transplantation. CMV infection was detected in 115 samples from 22 patients by US17-PCR and 69 samples from 20 patients by the antigenemia assay. Fifty-eight samples were positive for both assays, but 57 and 11 samples were positive only for US17-PCR and antigenemia, respectively. A good correlation of the results of US17-PCR and antigenemia was demonstrated (r = 0.61). All antigenemia-positive samples and randomly selected antigenemia-negative samples were subjected to IE-PCR. The results of IE-PCR showed a good correlation with those of antigenemia (r = 0.64). Furthermore, the best correlation was observed between US17-PCR and IE-PCR (r = 0.83). In conclusion, both real-time PCR methods showed a good correlation with the antigenemia assay, and could be used to monitor CMV infection after hematopoietic stem cell transplantation.

Antigens, Viral↗
PubMed2002

Association between IL-4 genotype and IL-4 production in the Japanese population.

We have identified that there are only two IL-4 gene haplotypes (I and II) in the Japanese population. There are significant differences among three genotypes (I/I, I/II and II/II) in the IL-4 producing proportion of peripheral Th cells using intracellular cytokine detection assay. These results make it likely that IL-4 genotype could influence the type of immune response.

Cells, Cultured↗
PubMed2002

Quantification of minimal residual disease in patients with e1a2 BCR-ABL-positive acute lymphoblastic leukemia using a real-time RT-PCR assay.

Using a real-time RT-PCR method, we analyzed the expression of e1a2 BCR-ABL mRNA in bone marrow samples from 13 patients with e1a2 BCR-ABL-positive acute lymphoblastic leukemia (ALL) at different time points during chemotherapy and after bone marrow transplantation (BMT). The detection limit of the method, assessed using serial dilutions of ALL/MIK cells, was found to be 1:10(5), similar to what is observed for the conventional RT-nested PCR method. The e1a2 BCR-ABL values were normalized with respect to those of the housekeeping gene GAPDH. The decrease in the e1a2 BCR-ABL/GAPDH ratio after remission induction chemotherapy reflects well the response to chemotherapy and consequently correlates with the prognosis. Although molecular remission was achieved by chemotherapy alone, some patients relapsed, and the e1a2 BCR-ABL/GAPDH ratios in these cases progressively increased to the levels seen prior to hematological relapse. Long-term hematological complete remission (more than 30 months) could be achieved in cases in which a more than 4.0 log decrease in the e1a2 BCR-ABL/GAPDH ratio was obtained by chemotherapy alone, and BMT was then performed. In conclusion, real-time RT-PCR allows for an evaluation of the kinetics of e1a2 BCR-ABL/GAPDH expression during the various phases of chemotherapy or after BMT and may be effective for the indication and control of disease relapse in Ph-positive ALL patients.

Adult↗
PubMed2002

CNR1, central cannabinoid receptor gene, associated with susceptibility to hebephrenic schizophrenia.

To examine the cannabinoid hypothesis for pathogenesis of schizophrenia, we examined two kinds of polymorphisms of the CNR1 gene, which encodes human CB1 receptor, a subclass of central cannabinoid receptors, in schizophrenics and age-matched controls in the Japanese population. Allelic and genotypic distributions of polymorphism 1359G/A at codon 453 in the coding region and AAT triplet repeats in the 3' flanking region in the Japanese population were quite different from those in Caucasians. Although the polymorphism 1359G/A was not associated with schizophrenia, the triplet repeat polymorphism of the CNR1 gene was significantly associated with schizophrenia, especially the hebephrenic subtype (P = 0.0028). Hebephrenic schizophrenia showed significantly increased rate of the 9 repeat allele (P = 0.032, OR = 2.30, 95% CI (1.91-2.69)), and decreased rate of the 17 repeat allele (P = 0.011, OR = 0.208, 95% CI (0.098-0.439)). The present findings indicated that certain alleles or genotypes of the CNR1 gene may confer a susceptibility of schizophrenia, especially of the hebephrenic type.

Adult↗
PubMed2002

Evidence that action potential generation is not the exclusive determinant to trigger spontaneous myogenic contraction of guinea-pig urinary bladder smooth muscle.

Urinary bladder smooth muscle (UBSM) exhibits spontaneous contraction. This spontaneous mechanical activity is myogenic and can be closely related to the UBSM cell action potential to facilitate Ca2+ influx through voltage-gated Ca2+ channels. In the present study, to know whether this membrane electrical event is the exclusive mechanism to trigger spontaneous smooth muscle contraction, we compared the inhibitory effects of Ca2+ channel blockers on the spontaneous action potential and mechanical activity in the isolated guinea-pig UBSM. Both action potential and rhythmic contraction were generated spontaneously in the presence of atropine (1 microM), phentolamine (1 microM), propranolol (1 microM), suramin (10 microM) and tetrodotoxin (1 microM), which suggest that both phenomena were myogenic in origin. Nisoldipine (100 nM) and diltiazem (10 microM) completely eliminated the generation of action potential whereas its frequency was dramatically increased by a dihydropyridine Ca2+ agonist, BayK 8644 (1 microM). In contrast to disappearance of action potential in the presence of Ca2+ channel blockers, spontaneous contraction of UBSM was inhibited only partly by nisoldipine or diltiazem and most of the mechanical components persisted in these channel blockers. These results indicate that spontaneous action potential in UBSM cell is generated through the activation of L-type voltage-gated Ca2+ channels. The subsequent elevation of intracellular Ca2+ concentrations during a burst of action potentials can be partly responsible for the induction of UBSM mechanical activity. In addition, the present study provides evidence that UBSM spontaneous mechanical activity is also attributable to the mechanism(s) other than the generation of Ca2+ spike.

Action Potentials↗
PubMed2002

The value of the chest computed tomography halo sign in the diagnosis of invasive pulmonary aspergillosis. An autopsy-based retrospective study of 48 patients.

To evaluate the diagnostic value of a halo on computed tomography (CT) in the diagnosis of invasive pulmonary aspergillosis (IPA), we retrospectively reviewed chest CT scans and autopsy reports for patients who had been admitted to our hospitals for the treatment of hematological malignancy. Pulmonary complications were suspected in all patients and chest CT scans were taken within a month of death. We examined the association between autopsy and CT findings in 48 patients who were diagnosed as IPA (n = 17), candidosis (n = 4), zygomycosis (n = 2), infiltration of hematological malignancy (n = 12), bacterial pneumonia (n = 6), cytomegalovirus pneumonia (n = 2), pulmonary hemorrhage (n = 2), or pulmonary congestion (n = 1). Patients with IPA showed a variety of CT findings, including halo (n = 13), nodules (n = 14), granular shadows (n = 3), masses (n = 6), consolidations (n = 9), wedge-shaped consolidations (n = 1), and cavitation (n = 2). In contrast, 0, 11 and two of the 31 patients without IPA showed halo, nodules and masses, respectively. These signs were more frequently observed in IPA patients than in non-IPA patients. The CT halo, especially, seemed to be specific for IPA in hospitalized neutropenic patients with hematological malignancies who developed antibiotic-resistant fever. For CT findings other than these three signs, there were no significant differences between IPA- and non-IPA patients.

Adolescent↗
PubMed2002

A highly selective direct method of detecting sulphate-reducing bacteria in crude oil.

AIMS: The aim of this work was to develop a highly selective method of detecting sulphate-reducing bacteria (SRB) in crude oil. METHODS: A pair of PCR primers was designed based on an alignment of the nucleotide sequence of the 16S rRNA genes from the Desulfovibrionaceae family. DNA extraction from crude oil was performed by the method using zirconia beads and a stool kit. RESULTS: The PCR specifically detected Desulfovibrio and Desulfomicrobium in a sediment sample. When nucleic acids extracted directly from crude oil were used for the PCR, 16S rRNA genes of Desulfovibrio and Thermodesulforhabdus norvegicus were detected. IMPACT OF STUDY: A simple direct method for detection of the SRB in crude oil using PCR was established.

DNA Primers↗
PubMed2002

Genetically determined interferon-gamma production influences the histological phenotype of lupus nephritis.

OBJECTIVE: To clarify whether the interferon-gamma (IFN-gamma) gene (IFNG) is associated with the histological phenotype of lupus nephritis. METHOD: We analysed microsatellite polymorphisms located within the first intron of the IFNG gene to determine the genotypes of patients with lupus nephritis WHO class IV (n=24), patients with WHO class V (n=12) and healthy controls (n=61). We used flow cytometric detection of intracellular cytokines to identify CD4(+) T cells producing IFN-gamma. Production of IFN-gamma by peripheral blood mononuclear cells after stimulation with phytohaemagglutinin was evaluated with an enzyme-linked immunosorbent assay. RESULT: The frequency of the IFNG allele 114 was significantly greater in WHO class V patients than in WHO class IV patients. Furthermore, the IFNG 114 +/+ genotype was more frequent in WHO class V than in WHO class IV patients. The level of IFN-gamma and the percentage of IFN-gamma-producing CD4(+) T cells were lower in individuals with genotype 114 +/+ than in individuals with genotype 114 -/-. CONCLUSION: The IFN-gamma gene is associated with the histological phenotype in lupus nephritis.

Adult↗
PubMed2002

Preoperative risk factors of intraoperative hypothermia in major surgery under general anesthesia.

UNLABELLED: Preoperative factors, such as age and body habitus, affect intraoperative hypothermia during general anesthesia. In a preliminary study, we developed a logistic model to retrospectively evaluate predictors of intraoperative hypothermia in patients who received major surgery. The following factors were selected to develop the model: Z = -15.014 + 0.097 x (Age) + 0.263 x (Height) - 0.323 x (Weight) - 0.055 x (Preoperative systolic blood pressure) - 0.121 x (Preoperative heart rate). By using this model, the probability of hypothermia can be estimated by applying the following formula: Probability = 1/(1 + e(-)(Z)). If an estimated probability of hypothermia was >0.5, the sensibility of prediction was 81.5% and the specificity was 83%. In the second study, the model was applied prospectively to other patients, and the validity of the logistic model was evaluated. The core temperature showed a significant decrease in patients with a probability >0.7, who were predicted to be hypothermic, and their thermoregulatory vasoconstriction threshold also showed a significant decrease, compared with the patients with a probability <==0.3, who were predicted to be normothermic. We concluded that intraoperative hypothermia could be predicted from preoperative characteristics such as age, height, weight, systolic blood pressure, and heart rate. IMPLICATIONS: Increases in age and height and decreases in weight systolic blood pressure and heart rate are major preoperative risk factors of intraoperative hypothermia during major surgery.

Aged↗
PubMed2002

Subtalar arthrography in recurrent instability of the ankle.

Subtalar arthrography was done in 37 feet of 35 patients in whom recurrent instability of the ankle was diagnosed. There were 16 male and 19 female patients, with a mean age of 29.1 years (range, 11-56 years). The mean interval between the injury and arthrography was 4 years 3 months (range, 6 months-22 years). Anteroposterior, lateral, and oblique radiographs were obtained for all patients. Any leakage during arthrography into the ankle, tendon sheaths, or sinus tarsi was recorded. An oblique view of the microrecess along the interosseous ligament and an anteroposterior view of the lateral recess just under the end of the fibula were examined. At surgery, 13 feet had combined injuries of the anterior talofibular and calcaneofibular ligaments, and 24 feet had isolated injury of the anterior talofibular ligament. The findings of the two groups were significantly different when examined for leakage into the ankle, leakage into the peroneal tendon sheath, and the presence of the lateral recess. Presence of contrast medium in at least two of these three positive arthrographic findings showed 92.3% sensitivity and 87.5% specificity in making the diagnosis of calcaneofibular ligament injury. Subtalar arthrography is valuable in making the diagnosis of calcaneofibular ligament injury in recurrent instability of the ankle.

Adolescent↗
PubMed2002

Fixation of osteochondral lesions of the talus using cortical bone pegs.

We have treated osteochondral lesions of the talus using cortical bone pegs. We examined 27 ankles (27 patients) after a mean follow-up of 7.0 years (2 to 18.8). The mean age of the patients was 27.8 years (12 to 62). An unstable osteochondral fragment or osteosclerotic changes in the bed of the talus were regarded as indications for the procedure. The clinical results were good in 24 ankles (89%) and fair in three (11%); none had a poor result. There was also radiological improvement in 24 ankles. Repair of the articular surface and stability of the lesion can be achieved even in unstable chronic lesions.

Adolescent↗
PubMed2002

CD44: functional relevance to inflammation and malignancy.

CD44 is a principal cell surface receptor for hyaluronan, a major component of extracellular matrices. Cells are surrounded by and encounter matrix in vivo, which in turn serves a variety of cell functions through the direct adhesion via their receptors. CD44 communicates cell-matrix interactions into the cell via "outside-in signaling" and has an important role in biological activities. The interaction of CD44 with fragmented hyaluronan on rheumatoid synovial cells induces expression of VCAM-1 and Fas on the cells, which leads to Fas-mediated apoptosis of synovial cells by the interaction of T cells bearing FasL. On the other hand, engagement of CD44 on tumor cells derived from lung cancer reduces Fas expression and Fas-mediated apoptosis, resulting in less susceptibility of the cells to CTL-mediated cytotoxicity through Fas-FasL pathway. Thus, although the CD44-mediated signaling differs among cells and circumstances, we here propose the functional role of CD44 in inflammatory processes and tumor susceptibility and the rational design of future therapeutic strategies including the exploitation of CD44-mediated pathway in vivo.

Animals↗
PubMed2002

Combinatorial peptide library for the analysis of antigen recognition by T cells.

Peptides that consist of 19 residues with random sequences (X19) were considered to deliver antigenic stimuli to CD4T cells. When IL-4, IL-7, IL-9, IL-15 and agonistic Ab to CD29 were co-cultured with single peripheral CD4T cells in the presence of X19 and feeder cells, T cells exhibited clonal expansion. These T cell clones showed heterogeneous proliferation patterns against KGXXXXXXXXXGK-based and KGXXXXXXXXXGKGKK-based combinatorial peptide libraries. Pattern-match search on one of the T cell clones resulted in peptide ligand candidates, one of which induced proliferation, as did protein molecules carrying the corresponding sequence. Combinatorial chemistry was useful in determining not only peptide ligands but also peptide superagonists. For this purpose, use of reverse-phase hydrophobic interaction chromatography and mass spectrometry analysis was efficient. Detailed methods are described in the paper.

Amino Acid Sequence↗
PubMed2002

Application of toxicity monitor using nitrifying bacteria biosensor to sewerage systems.

Toxic substances may be included in wastewater influent and can damage biological processing of wastewater treatment, therefore continuous toxic-monitoring of wastewater influent is needed. This paper describes the potential toxic-monitoring applications of the toxicity monitor using a nitrifying bacteria biosensor to sewerage systems. The results of sensitivity tests show that aspects of wastewater do not affect the sensor sensitivity and confirm that the sensor can be applied to wastewater monitoring as it is. The monitor with a prototype of filtration system installed in a wastewater treatment plant is able to operate continuously for one month at least after the modification of filtration system and the optimization of operation conditions.

Biosensing Techniques↗
PubMed2002

Development of a health guidance support system for lifestyle improvement. Committee of Health Evaluation Support System Council of Japan AMHTS Institutions.

OBJECTIVE: To provide automated advice for lifestyle adjustment based on an assessment of the results of a questionnaire and medical examination or health checkup data. METHODS: A system was developed that gathers data based on questions regarding weight gain, exercise, smoking, sleep, eating habits, salt intake, animal fat intake, snacks, alcohol, and oral hygiene; body mass index, resting blood pressure, fasting blood sugar, total cholesterol, triglycerides, uric acid and liver function tests. Based on the relationships between the lifestyle data and the health checkup data, a health assessment sheet was generated for persons being allocated to a multiple-risk-factor syndrome group. RESULTS: Health assessment and useful advice for lifestyle improvement were automatically extracted with the system, toward the high risk group for lifestyle related diseases. The system is operational. CONCLUSIONS: We developed a health guidance support system for lifestyle improvement. In comparison with conventional, limited advice methods, we developed a practical system that defined the necessity for lifestyle improvement more clearly, and made giving advice easier.

Counseling↗
PubMed2002

A possible role of VEGF in osteolytic bone metastasis of hepatocellular carcinoma.

The incidence of bone metastasis was around 13% in 404 patients with hepatocellular carcinoma (HCC) who underwent treatment at the National Kyushu Cancer Center between 1988-97, which is a high value among various cancers. This is, in part, due to the prolonged survival time of HCC patients in recent years. Serum vascular endothelial growth factor (VEGF) levels were significantly elevated in HCC patients with bone metastases as compared to those in patients with liver cirrhosis/chronic hepatitis and HCC patients without bone metastasis. VEGF was positively stained in both the primary lesion and bone metastasis of HCC by immunohistochemistry. In the process of bone metastasis, an increase in bone resorption is a crucial step prior to invasion of the bone. VEGF, the most important angiogenic factor, has been shown to stimulate bone resorption through its effects on osteoclasts. Thus, HCC cells reach the bone marrow space, and then secrete VEGF which facilitates osteolytic bone metastasis. VEGF may also facilitate tumor growth in the bone by acting as an angiogenic factor once invasion of the bone is complete. This might be another reason for the high incidence of bone metastasis in HCC.

Biomarkers, Tumor↗