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Biomedical subjects

S Tamura

Publications and source records attributed to S Tamura.

At least 415 records · Page 23Linked to original sources
PubMed1993

Genotypic analysis of Epstein-Barr virus associated with nasopharyngeal carcinoma of Japanese patients.

Types and certain genetic markers were studied for Epstein-Barr virus present in 10 specimens of nasopharyngeal carcinoma (NPC) from Japanese patients. The type 1 virus was predominant in our NPC specimens, as in the general Japanese population, and the type 2 virus was found only in one NPC specimen. The type C variant, which lacks the BamHI site between the BamHI-W1* and -I1* regions, appeared to be common among Japanese strains as in those in Southern China. The type f variant which has an extra BamHI site in the BamHI-F region and has been shown to be strongly associated with NPC in Southern China was found in only one NPC specimen. This virus strain was also the only type 2 virus among our specimens. The present study, therefore, does not show any specific association of the type f variant with NPC in Japan.

Adult↗
PubMed1993

Clonal evolutions during long-term cultures of bone marrow from de novo acute myeloid leukaemia with trilineage myelodysplasia and with myelodysplastic remission marrow.

We previously established a long-term bone marrow culture (LTBMC) system in which novel abnormal karyotypes could emerge in vitro prior to the appearance of the same karyotypes in vivo in patients with myelodysplastic syndrome (MDS). We extended our study to examine whether acute myeloid leukaemia (AML) transformed from MDS (MDS/AML) and de novo AML with trilineage myelodysplasia (AML/TMDS) show clonal evolution in LTBMC similar to that of typical AML or MDS. We also analysed the cytogenetic changes in cultures with bone marrows from AML with myelodysplastic remission marrow (AML/MRM) as well as chronic myeloid leukaemia (CML) to compare them with typical AML with respect to the liability of clonal evolution. Among the 34 AML cases, abnormal karyotypes were newly detected in four of seven MDS/AML, three of six AML/TMDS and three of three AML/MRM. Novel abnormal karyotypes were also observed in nine out of 13 CML cases after culture. In contrast, no other abnormal karyotypes were found after culture in 18 typical AML without myelodysplasia. These findings suggest that AML/TMDS and AML/MRM are different from typical AML and are similar to MDS/AML and CML in view of their potential for disease progression from latent multiple clones. Typical AML may develop from a single abnormal clone without any subclones.

Anemia, Aplastic↗
PubMed1993

A Ki-1-positive cell line expressing Epstein-Barr virus antigens, established from a child with Ki-1-positive lymphoma.

We report here the establishment of a CD30 (Ki-1) antigen-positive cell line 'Ki-JK' from a child with anaplastic large cell lymphoma. We characterized this cell line and show that: (i) Ki-JK cells do not grow in soft agar but infrequently produce a tumor or suppressed growth when injected into nude mice; (ii) Ki-JK cells expressed Epstein-Barr virus (EBV) antigens, EBV-associated nuclear antigen-2 and latent membrane protein; (iii) Ki-JK cells are labelled by in situ hybridization using an RNA probe derived from the BamHI W fragment of EBV, and (iv) polymerase chain reaction demonstrates the presence of an EBV BamHI W sequence in DNA of lymphoma and Ki-JK cells. These results suggest an etiological role for EBV in the development of some cases of Ki-1-positive lymphomas.

Adolescent↗
PubMed1993

Pulmonary manifestations in adult T-cell leukemia at the time of diagnosis.

Adult T-cell leukemia (ATL) is an underlying immunodeficient condition which often leads to various kinds of pulmonary diseases. We have analyzed 35 consecutive patients (18 male, 17 female) with ATL to see to what extent pulmonary complications were involved at the time of diagnosis. Over one-third presented with respiratory symptoms and 14 (40%) patients had significant findings on chest radiographs on the first admission in which reticulo-nodular shadows were predominant in 10 patients, suggesting that overt ATL is preceded by interstitial pulmonary disease. In addition, bacterial pneumonia and pneumocystosis were experienced in over two-thirds of the patients during the clinical course, and more than half of the patients subsequently died of pulmonary complications suggesting that early institution of diagnostic procedures and treatment for pulmonary conditions is needed in ATL patients.

Female↗
PubMed1993

Mononuclear cell infiltration and its relation to the expression of major histocompatibility complex antigens and adhesion molecules in pancreas biopsy specimens from newly diagnosed insulin-dependent diabetes mellitus patients.

We examined pancreas biopsy specimens from 18 newly diagnosed insulin-dependent diabetes mellitus (IDDM) patients to elucidate the mechanism underlying beta cell destruction. Pancreas islets were seen in all patients and insulitis in eight patients. Infiltrating mononuclear cells consisted of CD4+T, CD8+T, B lymphocytes, and macrophages. Among them, CD8+T lymphocytes were predominant and macrophages followed. The expression of MHC class I antigens was increased in islet and endothelial cells in nine patients. MHC class II expression was increased in endothelial cells of the same patients. The expression of intercellular adhesion molecule-1 was increased in endothelial cells in two of the nine patients with MHC hyperexpression; in one of them, lymphocyte function-associated antigen-3 expression was also increased. Out of the eight patients with insulitis, seven showed MHC class I hyper-expression, whereas 2 of the 10 patients without insulitis showed the phenomenon (P < 0.05). The relation between insulitis and the hyperexpression of adhesion molecules was not evident. In conclusion, we revealed the close relation between CD8+T lymphocyte-predominant insulitis and MHC class I hyperexpression in islet cells. This suggests that infiltrating CD8+T lymphocytes recognize islet autoantigens in association with increased MHC class I molecules and act as major effector cells in autoimmune response against islet cells in IDDM pancreases. The role of adhesion molecules in the pathogenesis of IDDM still remains to be elucidated.

Adolescent↗
PubMed1993

[A survey of primary lung cancer among NTT workers in the Tokyo area. The incidence and mortality during the past 30 years and significance of radiologic screening].

An epidemiological study of primary lung cancer was conducted on NTT workers in the Tokyo area (about 40,000 persons). During the past 30 years (1960-1989), 77 cases (71 males and 6 females) of primary lung cancer were detected by routine medical examination (radiologic screening by radiophotography at their workplaces) or by clinical symptoms, of whom 59 (54 males and 5 females) were dead as of the end of December 1991. Standardized incidence rate and standardized death rate of the males by the direct method (5-yr age groups from 20 to 59 yr of age, per 100,000 population) were 4.5 in the 1960's, 9.9 in the 1970's and 9.8 in the 1980's, and 3.3 in the 1960's, 7.9 in the 1970's and 8.2 in the 1980's, respectively, with increase being observed from the 1970's. Standardized incidence ratio and standardized death ratio of the males by the indirect method (5-yr age groups from 20 to 59 yr of age) were 107 in the 1970's, 86.8 in the 1980's, and 53.8 in the 1960's, 99.4 in the 1970's and 98.5 in the 1980's, respectively. No significant difference could be observed when compared to the national average. By histological type, 44 cases of adenocarcinoma, 12 cases of squamous cell carcinoma, 8 cases of small cell carcinoma, 7 cases of large cell carcinoma and 6 cases of other or unclear types were detected. Excluding the 3 unclear cases, of the 77 cases, 54 cases were peripheral type and the remaining 20 cases were hilar type on radiophotography. Peripheral adenocarcinoma was the most common type.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Analysis of viral infection in patients with IgA nephropathy.

We investigated viral infections in the tonsils, pharynx and renal tissues of patients with IgA nephropathy using cell culture, polymerase chain reaction (PCR) and immuno-fluorescent techniques, and measured antibody titers against numerous types of viruses. Neutralization tests found no significant inhibition of growth of adenovirus-1, 2, 3, 4, 5, 6, 7, 11 or 19, Coxsackie virus-A7, A9, A16, B1, B2, B3, B4, B5 or B6, or RS virus. Swabs of the oral cavity of patients with IgA nephropathy were cultured with Hel cells, MDCK cells, FL cells, BHK-21 cells and RD-18S cells. No cytopathic effect was detected in any of these cell cultures. We failed to detect the presence of herpes simplex virus-1 and -2, varicella-zoster virus, cytomegalovirus and Epstein-Barr virus (EBV)-1 and -2 in tonsils, renal tissues and mouthwashings from patients with IgA nephropathy. On the other hand, EBV alone was detected with the PCR technique, in mouthwashings from 6 out of 14 patients with IgA nephropathy (42%). Immunohistological and serological analyses were done to examine the relationship between EBV and IgA nephropathy. No evidence was obtained that EBV-infected B lymphocytes were producing IgA. It seems unlikely that the viral infections examined in this study play a significant role in the pathogenesis of IgA nephropathy.

Adult↗
PubMed1993

Effect of and indication for tonsillectomy in IgA nephropathy.

Although more than 20 years have passed since the initial report of IgA nephropathy, the etiology of this disease is still unclear. Some reports suggest that the tonsil is an important etiological factor. We performed tonsillectomy on 26 patients with IgA nephropathy associated with chronic tonsillitis, and followed up the patients for two years after the operation to evaluate its clinical effect on this disease. Twelve patients (efficacy rate 46%) showed distinct improvement in urinary findings after the operation, although the efficacy rate went down as renal injury advanced. Serum IgA levels decreased significantly after the operation both in patients who improved and in those who did not; the decrease was especially evident in patients who had high levels of serum IgA before tonsillectomy. In 4 patients who improved, the level of circulating immune complex (CIC) was extremely high before, and decreased significantly after, the operation. One patient suffered renal failure three years after tonsillectomy. When renal injury has advanced to the clinically apparent degree, as occurred in this patient, tonsillectomy is absolutely contraindicated. In reaching a decision as to whether tonsillectomy is indicated in mild cases, the change in the number of erythrocytes in urinary sediments may be a sensitive parameter of the tonsillar provocation test.

Adult↗
PubMed1993

Application of long-term bone marrow cultures for studying the leukemic transformation of myelodysplastic syndromes.

Myelodysplastic syndrome (MDS) has been thought to be an identifiable early stage in multistep leukemogenesis. Considerable numbers of patients with MDS eventually develop acute myelogenous leukemia (AML), which is very much more difficult to manage than typical denovo AML. There are several differences in both the clinical and biological behavior of AML with and without prior MDS. We have established an unique long-term bone marrow culture (LTBMC) system which allows abnormal cells to grow in preference to normal cells, based on the method originally described by Dexter et al. Leukemic transformations occur more frequently in MDS patients with abnormal karyotypes, and particularly those with multiple abnormalities. New cytogenetic abnormalities were occasionally observed at the time of transition to AML. We have applied this LTBMC system for cytogenetic and molecular studies on the leukemic transformation from MDS. Among the 32 patients with MDS studied thus far, novel abnormal karyotypes were detected during the LTBMCs in 15 patients. Furthermore, 6 out of 23 novel karyotypes detected during the in-vitro cultures emerged in vivo, one to 11 months later in 4 patients. In addition, point mutation of the N-ras proto-oncogene was observed in 3 of 18 cases. The signal of the dot-blot hybridization was increased in one examined case after 2 weeks in culture. Thus, this LTBMC system may provide some promising information with respect to understanding the multistep process from the preleukemic stage to the development of overt leukemia as well as its prognostic relevance.

Bone Marrow↗
PubMed1993

Drinking habits influence the relationship between apolipoprotein AII and body mass index.

The relationships of cigarette smoking, exercise, and body mass index (BMI) to the serum levels of high-density lipoprotein (HDL) cholesterol, apolipoprotein AI (Apo AI), apolipoprotein AII (Apo AII), and % of HDL cholesterol to total cholesterol (%HDL-C) were assessed in 495 employees of a telephone company in Japan. They were subdivided into four groups by frequency of alcohol intake: nondrinkers (n = 28), those who drank once per week (n = 78), those who drank 2 to 5 times per week (n = 245), and those who drank 6 to 7 times per week (n = 144). Although univariate analysis before grouping showed a positive correlation between Apo AII and BMI, multiple analysis examined in each group showed the positive relationship only in the nondrinking group. The relationship between BMI and Apo AII would thus appear to depend on drinking habits.

Adult↗
PubMed1993

Comparison of neural network and k-NN classification methods in medical image and voice recognitions.

We make a comparison of classification ability between BPN (Back Propagation Neural Network) and k-NN (k-Nearest Neighbor) classification methods. Voice data and patellar subluxation images are used. The result was that the average recognition rate of BPN was 9.2 percent higher than that of the k-NN classification method. Although k-NN classification is simple in theory, classification time was fairly long. Therefore, it seems that real time recognition is difficult. On the other hand, the BPN method is long in learning time but is very short in recognition time. Especially if the number of dimensions of the samples is large, it can be said that BPN is better than k-NN in classification ability.

Algorithms↗
PubMed1993

[E-cadherin expression and cancer invasion and metastasis].

E-cadherin (ECD) is a transmembrane glycoprotein that mediates the calcium dependent adhesion of cells and plays a major role in cell-cell adhesion of normal epithelium. In present study, we have established the positive ECD expressed clone (ECD(+)) and the negative ECD expressed clone (ECD(-)). Anti human ECD monoclonal antibody (HECD-1) disturbed the mutual adhesion of ECD(+) effectively but didn't disturb that of ECD(-). ECD(+) did not invade the collagen/fibroblast gel, but ECD(-) did. Furthermore, ECD(+) acquired invasiveness in the collagen gel when HECD-1 was used. Clinicopathologically, we have investigated the correlation between expression of ECD and metastasis in human esophageal and gastric cancers by immunohistochemical staining using HECD-1. ECD expression of these lymph node metastatic tumor in the primary sites was more reduced than that of non metastatic tumor significantly. These results indicated that reduction or dysfunction of ECD diminishes intercellular adhesion and acquires invasive and metastatic capacity in human cancer cells.

Cadherins↗
PubMed1993

[Antitumor activity of various cytostatics in mice bearing murine advanced tumors].

Antitumor activities of cytostatics such as 5-FU, 5'-DFUR, cyclophosphamide (CPA), ACNU, CDDP, mitomycin C (MMC) and doxorubicin (DXR) were compared in mice bearing four different murine-tumor models at two different stages of the tumor growth. All cytostatics tested suppressed the tumor growth in most of the four tumors, colon 26 carcinoma, UV 2237 fibrosarcoma, Ehrlich carcinoma and Meth A fibrosarcoma, when the tumor sizes were small (early transplant). When given to mice bearing advanced tumors, 5-FU, CDDP, MMC and DXR were effective only at the higher doses, showing toxicity. In contrast, 5'-DFUR was equally effective against both most of early and advanced tumors except for advanced Meth A against which higher doses of 5'-DFUR were needed. CPA and ACNU equally suppressed the growth of early transplant and advanced tumors of Meth A, although higher doses were needed against advanced tumors of three others. 5'-DFUR was also effective against tumor cachexia (colon 26) and spontaneous metastasis (Lewis lung carcinoma), which are characteristically observed in mice bearing advanced tumors. CPA also showed an anticachectic activity, though the activity was weaker than that of 5'-DFUR. These results suggest that 5'-DFUR and CPA can be used in both intensive and adjuvant chemotherapies.

Animals↗
PubMed1993

[Results of initial bacteriology of pulmonary tuberculosis among male NTT employees in the Tokyo area--annual transition and influence of fiberoptic bronchoscopy].

A study was made on the annual changes in the positive rate for acid-fast bacilli (AFB) at the initial bacteriological examination of newly detected pulmonary tuberculosis among male NTT (Nippon Telegraph and Telephone Corporation) employees in the Tokyo area during a period of 32 years from 1960 through 1991. The influence on the changes of recent introduction of fiberoptic bronchoscopy for obtaining the specimen was also analyzed, and the following results were obtained. 1. Results obtained by the conventional bacteriological method using expectorated sputum or aspirated gastric juice as the specimens. (1) The annual incidence of bacteriologically positive (smear and/or culture positive) cases constantly decreased and reached the lowest in 1981, then ceased to decline and remained at the level of 1981. (2) The annual ratio of AFB positive by smear and the ratio of smear and/or culture positive cases to the newly detected cases of pulmonary tuberculosis were constant during the entire observation period. (3) The ratio of AFB positive by smear to the newly detected cases annually increased but did not increase when the observation period was limited to within 1976 to 1991. 2. Results obtained by fiberoptic bronchoscopy in combination with conventional bacteriological methods. (1) Both the annual incidence of smear and/or culture positive cases and the ratio of these cases to the newly detected cases of pulmonary tuberculosis showed a tendency to increase in both the 80's and 90's.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Postoperative motor function and mucosal blood flow of lower esophagus: comparison between terminal esophagoproximal gastrectomy and esophageal transection for esophageal varices.

Reflux esophagitis and anastomotic ulcer are potential complications associated with surgery for esophagogastric lesions. This study compared 10 cases following terminal esophagoproximal gastrectomy (TEPG) for esophageal varices and 20 cases following esophageal transection (ET) for esophageal varices with respect to postoperative motor function and mucosal blood supply, to ascertain the reason for the development of anastomotic ulcer. Endoscopic findings showed that anastomotic ulcers were detected more often after TEPG than after TR. Maximum swallowing pressure, high pressure zone pressure, and length did not differ between the two groups. However, maximum swallowing pressure in the lower esophagus after both procedures was significantly lower than in the control group (20 cases; p < 0.01). The results, measured by reflectance spectrophotometry, showed that the index of esophageal mucosal blood volume following TEPG is significantly lower than that following ET and in non-operated esophageal varices (10 cases; p < 0.01). Yet the index of oxygen saturation of hemoglobin was similar in the three groups. This study has demonstrated that patients undergoing TEPG have mucosal ischemia of the lower esophagus, causing the development of anastomotic ulcers.

Anastomosis, Surgical↗
PubMed1993

Single-exposure dual-energy chest images with computed radiography. Evaluation with simulated pulmonary nodules.

RATIONALE AND OBJECTIVES: Dual-energy subtraction radiography using computed radiography (CR) can aid in the detection of pulmonary abnormalities such as nodules, but the subtracted image requires higher x-ray exposure than usual to reduce quantum mottle. To reduce quantum mottle without increasing x-ray exposure, a new dual-energy subtraction algorithm was investigated that included an edge-adaptive smoothing process and a subtraction process. The signal-to-noise ratio and the image quality of this new subtracted image was significantly superior to that of conventional subtracted images. METHODS: Observer performance of the subtracted digital radiography in detecting simulated pulmonary nodules was compared with original CR images and conventional subtracted digital radiography of 50 patients. RESULTS: A combination of an original CR image and a new subtracted CR image was significantly superior to a single original CR image or a combination of an original CR image and a conventional subtracted CR image (P < .01). DISCUSSION: The single-exposure dual-energy subtraction method is superior to the conventional subtraction method in the detection of pulmonary nodules.

Humans↗
PubMed1993

[Alternative combination chemotherapy with mitomycin C, vincristine, methotrexate, 5-fluorouracil, cis-platinum and adriamycin for adenocarcinoma of the lung].

Efficacy of an alternative combination chemotherapy with MMC, VCR, MTX, 5-FU, CDDP and ADM for adenocarcinoma of the lung is reported. Forty-one advanced cases (stage III: 9; IV: 32) were chosen for the chemotherapy. Two combination chemotherapies MMC + VCR + MTX + 5-FU + CDDP: MVMFP; MMC + VCR + MTX + 5-FU + ADM: MVMFA were repeated alternatively for 8 consecutive weeks with 2 interposed rest weeks, and this regimen was completed in 34 cases. All 41 cases were evaluable. Three and 26 cases achieved complete and partial responses, respectively. The response rate was 70.7%, and the median survival time was 13 months. The adverse effects of the chemotherapy observed were tolerable: alopecia (63.4%), gastrointestinal symptoms (14.5%), bone marrow toxicity (12.2%) and liver dysfunction (4.8%). These results indicate that our MVMFP/MVMFA alternative chemotherapy is quite effective for adenocarcinoma of the lung, comparable or superior to conventional chemotherapies.

Adenocarcinoma↗