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T Tsuchiya

Publications and source records attributed to T Tsuchiya.

At least 73 records · Page 4Linked to original sources
PubMed2001

Role of desethylamiodarone in the anticoagulant effect of concurrent amiodarone and warfarin therapy.

BACKGROUND: The concurrent use of amiodarone and warfarin inhibits metabolism of S-warfarinby cytochrome P450 (CYP) 2C9, thereby increasing the anticoagulant effect of warfarin. Amiodarone primarily inhibits CYP1A2 and CYP3A4, and desethylamiodarone primarily inhibits CYP2C9. We investigate whether a relationship exists between the plasma concentration of desethylamiodarone and anticoagulation when amiodarone is administered to patients receiving warfarin therapy. METHODS AND RESULTS: The correlation between the plasma concentration of either amiodarone or desethylamiodarone, and prolongation of prothrombin time-international normalized ratio/dose of warfarin (Delta INR/Dose) on day 7 of amiodarone administration was studied in 25 patients (22-74 years old) with structural heart disease and refractory arrhythmias receiving stable warfarin therapy. RESULTS: No correlation was found between the plasma concentration of amiodarone and Delta INR/Dose, but a correlation was found between the plasma concentration of desethylamiodarone and Delta INR/Dose. CONCLUSIONS: It was suggested that inhibition of CYP2C9 by desethylamiodarone, the active metabolite of amiodarone, plays an important role in the interaction of warfarin and amiodarone.

Adult↗
PubMed2001

Geranylgeranylacetone protects guinea pig gastric mucosal cells from gastric stressor-induced necrosis by induction of heat-shock proteins.

Gastric mucosal cell death due to various gastric stressors can cause several types of gastric diseases, such as gastric ulcers. In this study, we examined cell death following the short-term treatment of guinea pig gastric mucosal cells in primary culture with various gastric stressors. The short-term treatment of cells with ethanol, hydrogen peroxide or hydrochloric acid caused, in a dose-dependent manner, cell death in the absence of apoptotic DNA fragmentation and chromatin condensation. Cells lost membrane integrity following the treatment with each of these gastric stressors, suggesting that necrosis was induced in gastric mucosal cells by short-term treatment of the cells with gastric stressors. Geranylgeranylacetone, an anti-ulcer drug with heat-shock protein inducing properties, protected gastric mucosal cells from the necrotic cell death caused by each of these gastric stressors. Pretreatment of cells with low concentrations of ethanol (3%), which also induced heat-shock protein, made cells resistant to the necrotic cell death caused by the gastric stressors. These results suggest that heat-shock proteins is involved in the cytoprotective effect of geranylgeranylacetone against necrotic cell death.

Animals↗
PubMed2001

[The trend of the drug eruptions in the last fifteen years].

The drug eruptions are known to often become more severe by the readministration of causative drugs. It is an important theme to prevent the relapse of the drug eruptions. We have been monitoring drug adverse reactions at our hospital since October, 1980. We divided fifteen years from October, 1980 to September, 1995 into three periods; the first period (Oct., 1980-Sep. 1985), the second period (Oct., 1985-Sep., 1990), and the third period (Oct., 1990-Sep., 1995), and discussed the trend of the drug eruptions appeared among these three periods. The number of the drug eruptions increased. But the proportion to the total drug adverse reactions and to the number of patients slightly decreased. The eruptions in women much increased and in the patients of forties or older generations also increased. But in patients of thirties or younger generations decreased. While nonsteroidal anti-inflammatory drugs (NSAIDs) other than pyrines, antibiotics other than penicillins and cephalosporins and drugs affecting the cardiovascular system and the metabolism tend to increase, pyrines, penicillins, iodic and biliary contrast media tend to decrease. The incubation period before the eruption appeared is less than three days in most antibiotics and anti-inflammatory drugs. But it is more than four days in most drugs for chronic diseases. Other symptoms such as nausea, fever and liver dysfunction were shown in 9.2% of the drug eruptions. In 8.9% of the drug eruptions a relapse of allergic reactions included eruptions were also found. In some cases the drug eruptions exacerbate by re-administration of beta-lactam antibiotics. In the case of administration of drugs, it is necessary to pay attention to dermatitis caused by the drugs. And we recognized the importance of the system for the prevention of the relapse of drug eruptions including injections.

Adolescent↗
PubMed2001

Immunohistochemical characterization of hepatoblastomas in B6C3F1 mice treated with diethylnitrosamine and sodium phenobarbital.

Hepatoblastomas (HBs) were induced in B6C3F1 male mice by diethylnitrosamine (DEN) and sodium phenobarbital (PB). Six-week-old mice received a single intraperitoneal dose of DEN followed by a continuous treatment with PB in diet at a concentration of 0 (group 1) or 500 (group 2) ppm for 50 weeks. HBs were observed in 13 of 21 (62%) group 2 mice, with typical histologic features as reported previously, while no such tumors were observed in group 1. Seven of 13 (54%) HBs were found in and/or adjacent to hepatocellular adenomas (HCAs) or hepatocellular carcinomas (HCCs). Immunohistochemically, all HBs were positive for S-100 protein but negative for keratin, alpha-fetoprotein (AFP), albumin (ALB) and vimentin, while HCC cells occasionally reacted positively for AFP with a mosaic pattern. HCC and HCA cells were occasionally positive for ALB. Non-neoplastic hepatocytes and normal bile ducts were positively stained for ALB and keratin/S-100 protein, respectively. S-100 protein is known to be expressed in many mesenchymal tissues and neoplasms including neuroectodermal elements but negative in cells of the hepatic lineage. Thus, the present immunohistochemical results suggested that mesenchymal differentiation occurs in mouse HB cells as observed in human HBs, one of the most frequent infant liver tumors in humans. Although the susceptibility of mouse HBs to PB-promotion suggests a hepatocytic histogenesis, the present immunohistochemical results support the hypothesis that the mouse HB is derived from pluripotent endodermal stem-like cells.

Albumins↗
PubMed2001

Familial adult onset primary alveolar hypoventilation syndrome.

A 41-year-old man fell into type II respiratory failure after catching a cold, and became dependent on a respirator. Chest radiography showed no abnormalities and the hyperventilation test showed improved arterial blood gas findings. His sleep study showed marked nocturnal desaturation due to hypopnea and apnea with a decrease of thoracic and abdominal movement during sleep. Therefore, we diagnosed him as primary alveolar hypoventilation syndrome (PAH). Seven years previously, his 2-year elder sister had suffered from similar respiratory failure during her second pregnancy and had been diagnosed as PAH. While myopathy was suspected in both cases, attenuation of muscle strength was slight and it appeared not to be the main cause of alveolar hypoventilation. Since medication was not effective in each case, they underwent non-invasive positive pressure ventilation (NIPPV). While sustained mild hypercapnia remained during the daytime, it improved their respiratory failure. To our knowledge, this is the first study of familial adult onset PAH.

Adult↗
PubMed2001

Defect of lck in a patient with common variable immunodeficiency.

Common variable immunodeficiency (CVID) is a congenital immunological disorder characterized by defective antibody production with normal count of peripheral B lymphocytes. The basic immunologic defects that leads to CVID are still unknown, however, a proportion of CVID is suggested to be caused by decreased CD4+ helper T cell activity. In addition, recent reports indicate that a defect of T cell receptor (TCR)-associated signaling molecules results in congenital immune deficiency in human. In the present study, we investigated lck, a signaling molecule downstream of TCR, in a patient with CVID plus CD4 lymphopenia, and found an aberrantly spliced lck transcript lacking the entire exon 7 associated with the decrease in the expression of lck protein. An identical splicing abnormality has been previously demonstrated in a case of severe combined immunodeficiency with selective CD4 lymphopenia, although the case showed almost complete loss of the expression of lck protein. Considering these findings, the aberrant splicing of lck gene is suggested to be correlated, at least with a subset of congenital immunodeficiency plus CD4 lymphopenia.

3' Untranslated Regions↗
PubMed2001

[Testicular pure teratoma: a case report].

A 46-year-old man visited our hospital, complaining of fever and painful swelling of the right scrotum contents. The symptoms and signs suggested epididymitis, but testicular tumor could not be excluded. Therefore, high inguinal orchiectomy was performed. Macroscopic findings were compatible with the testicular teratoma, containing hair, and epididymitis. Histological findings revealed that the tumor was composed of mature epidermis with skin appendages, cartilage, hair, bone and adipose tissue, and that many leucocytes infiltrated in the epididymis, resulting in the diagnosis of pure mature teratoma with epididymitis. For 6 months after the operation, no evidence of recurrence has been observed. Despite its histologically benign appearance, primary pure teratoma of the testis has a metastatic and recurrent potential. Therefore, primary pure teratoma should be man aged in the same way as other nonseminomatous germ cell tumors.

Humans↗
PubMed2001

Regulation of galactoside transport by the PTS.

Inducer exclusion, regulation of activity of transporter, is mediated by phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS). To elucidate the molecular mechanism of the inducer exclusion, numerous biochemical and genetic studies have been performed. It is now well known that non-phosphorylated IIA(Glc) inhibits the transport via direct binding to the transporter. Analysis of inducer exclusion resistant mutants of lactose transporter and melibiose transporter in Escherichia coli and Salmonella typhimurium revealed amino acid residues that are involved in the interaction with IIA(Glc). It is concluded that there are multiple interaction sites for IIA(Glc) in these transporters.

Amino Acid Sequence↗
PubMed2001

Finite element simulation of piezoelectric transformers.

Piezoelectric transformers are nothing but ultrasonic resonators with two pairs of electrodes provided on the surface of a piezoelectric substrate in which electrical energy is carried in the mechanical form. The input and output electrodes are arranged to provide the impedance transformation, which results in the voltage transformation. As they are operated at a resonance, the electrical equivalent circuit approach has traditionally been developed in a rather empirical way and has been used for analysis and design. The present paper deals with the analysis of the piezoelectric transformers based on the three-dimensional finite element modelling. The PIEZO3D code that we have developed is modified to include the external loading conditions. The finite element approach is now available for a wide variety of the electrical boundary conditions. The equivalent circuit of lumped parameters can also be derived from the finite element method (FEM) solution if required. The simulation of the present transformers is made for the low intensity operation and compared with the experimental results. Demonstration is made for basic Rosen-type transformers in which the longitudinal mode of a plate plays an important role; in which the equivalent circuit of lumped constants has been used. However, there are many modes of vibration associated with the plate, the effect of which cannot always be ignored. In the experiment, the double resonances are sometimes observed in the vicinity of the operating frequency. The simulation demonstrates that this is due to the coupling of the longitudinal mode with the flexural mode. Thus, the simulation provides an invaluable guideline to the transformer design.

Journal Article↗
PubMed2001

[A recurrent case of idiopathic interstitial pneumonia histologically diagnosed as nonspecific interstitial pneumonia group 1].

A 59-year-old man was admitted to our hospital because of dyspnea. Chest radiography showed infiltration and consolidation in both lung fields. He was clinically diagnosed as having idiopathic interstitial pneumonia (IIP), and histological examination of a thoracoscopic lung biopsy specimen showed nonspecific interstitial pneumonia (NSIP) group 1. Corticosteroid therapy had previously been effective, but about 1 year later the disease recurred. The patient's clinical condition was very similar to the first episode, and is improving in response to the same treatment again. Although it is generally accepted that patients with IIP diagnosed histologically as NSIP have a good prognosis, it should be remembered that recurrence is possible, even in patients with group 1.

Humans↗
PubMed2001

[Primary adenocarcinoma of the renal pelvis with a pyeloduodenal fistula: a case report].

A 62-year-old woman visited our hospital complaining of fever and right flank pain. On excretory pyelography the right kidney containing three renal stones was not visualized. Retrograde pyelography revealed an irregular filling defect in the right renal pelvis. Computed tomography revealed renal stones and a tumor mass in the right renal pelvis. From these findings, the pelvic tumor of the right kidney complicated by renal stones was diagnosed. Right nephrectomy was performed. Because a fistula between the renal pelvis and the second portion of the duodenum was found in the operation, partial resection of the duodenum was also performed. Pathological diagnosis was adenocarcinoma of the renal pelvis and pyeloduodenal fistula due to chronic pyelonephritis. Postoperative chemotherapy was not given. This is the first case report of adinocarcinoma of the renal pelvis coexisting with a pyeloduodenal fistula.

Adenocarcinoma↗
PubMed2001

[Secondary eosinophilia in a patient with hypereosinophilic syndrome after allogeneic bone marrow transplantation from a sibling donor].

A 23-year-old man first visited a local hospital in 1998 because of exertional dyspnea. Peripheral blood examination revealed mild leukocytosis with 82% eosinophils, and he was treated with prednisolone. As the eosinophilia did not improve, he was referred to Tokai University Hospital in March 1999 for further diagnosis and treatment. The patient was diagnosed as having hypereosinophilic syndrome (HES) because of unexplained hypereosinophilia persisting for more than 6 months, resulting in cardiac dysfunction. His disease was progressive in spite of immunosuppressive therapy, interferon-alpha and cytotoxic chemotherapy. Since he had an HLA-identical brother, allogeneic bone marrow transplantation (BMT) was performed in October 1999. After completion of the immunosuppressive therapy on day 79 after BMT, the number of eosinophils gradually increased again. Although we suspected recurrence of the disease, DNA fingerprinting revealed that the peripheral granulocytes were 100% donor type. An increase of interleukin-5 (IL-5) produced by peripheral lymphocytes and a decrease of the Th1/2 ratio suggested that the eosinophilia was related to GVHD. The eosinophilia was eventually controlled by cyclosporin. We conclude that DNA fingerprinting and examination of the IL-5 level and Th1/2 ratio are useful for differentiating between relapse and GVHD in cases of eosinophilia occurring after BMT for HES.

Adult↗
PubMed2001

[Tuberculosis of the elderly (above the age of 75) in national hospitals].

In Japan tuberculosis is becoming rapidly the disease of the elderly. We studied the background, the type and level of hospital cares needed, and the outcome of patients with pulmonary tuberculosis (sputum smear and/or culture positive) above the age of 75 who were admitted to 8 national hospitals during the period from January 1 to December 31, 1997. The study included 150 patients (male: 109, female: 41, mean age: 81.6), of whom 25% needed care in a single-bed room, 84.3% had underlying diseases (cardiovascular diseases: 43.3%, malignant diseases: 20.9%, neuro-psychiatric diseases: 13.4%), and 47.6% needed cares mainly in feeding and excretions. 92 patients (62.6%) improved and 45 patients (30.6%) died, of whom the cause of death was directly related to tuberculosis in 42. The mean hospital stay was 4.7 months. However, in 42 patients whose cause of death was related to tuberculosis, 66% died within 3 months, while in 102 patients who were discharged 71% stayed more than 3 months. The same comparison was done in 508 patients with bacteriologically proven tuberculosis above the age of 75 admitted to National Tokyo Hospital during the period from 1990 to 1999. The result was almost the same, among 133 patients died in the hospital 60% died within 3 months, while in 375 patients who were discharged hospital stay was more than 3 months in 70%. In the near future, the elderly will occupy more than 25% of the beds of the tuberculosis ward in Japan and most of them have underlying diseases other than tuberculosis. Because tuberculosis, once the disease of the young, is becoming rapidly the disease of the elderly, it is imperative for us to make necessary adjustments to meet this inevitable trend.

Aged↗