Search PubMed⌕ Search

Biomedical subjects

K Tamura

Publications and source records attributed to K Tamura.

At least 1,477 records · Page 82Linked to original sources
PubMedDate not supplied

Cerebral haemorrhage complicating adult-onset Still's disease: a case report.

The case of a 75-year-old Japanese woman with adult-onset Still's disease who presented with cerebral haemorrhage is described. She had been in clinical remission for 2 years, after induction therapy including non-steroidal anti-inflammatory drugs, prednisolone, cyclophosphamide and mizoribine followed by auranofin, until her cerebral haemorrhage occurred, although her serum level of ferritin had gradually increased. After the onset of cerebral haemorrhage, the patient's serum level of thrombomodulin was elevated although c-reactive protein and lactate dehydrogenase were not increased. Anti-cardiolipin antibody and lupus anti-coagulant were not detected. Patients with adult-onset Still's disease are rarely reported to develop cerebral vascular disease, possibly because the disease is most frequent in young adults. The cerebral haemorrhage may have been caused by the vasculitis due to Still's disease.

Adult↗
PubMedDate not supplied

Study of respirable suspended particulates and polycyclic aromatic hydrocarbons in indoor and outdoor air.

To study the concentration change of respirable suspended particulate (RSP) in indoor and outdoor air environment, a new portable sampler (AND-sampler) was made. The sampler could collect particles above 10 microns, 2 to 10 microns, and below 2 microns in aerodynamic diameter separately. The relationship between the airborne particulate concentration in indoor and outdoor air environment varied with the aerodynamic diameter of the particles. The concentration of RSP in indoor air environment increased in proportion to that in outdoor environment. Polycyclic aromatic hydrocarbons (PAH) concentration in airborne particulate also varies with the aerodynamic diameter of the particles. Fine particles below 2 microns in aerodynamic diameter contains high concentration of PAH. The PAH concentration in indoor air environment increases in proportion to that in outdoor air.

Air Pollution, Indoor↗
PubMedDate not supplied

Intrapericardial instillation of OK-432 for the management of malignant pericardial effusion: report of three cases.

Three patients with cardiac tamponade caused by malignancy were treated by pericardiocentesis with intrapericardial OK-432 instillation. The underlying disease was adenocarcinoma of unknown origin, breast cancer and multiple myeloma. Under electrocardiographic monitoring, a polyethylene catheter with several side holes was inserted into the pericardial sac, and after a maximal volume of fluid was withdrawn, 5 KE of OK-432 diluted in 20 ml of saline was instilled through the catheter. All the patients who received intrapericardial OK-432 therapy obtained complete control of pericardial effusion for more than 30 days. The side effects were fever, chills and chest pain which were easily controlled by antipyretics.

Adenocarcinoma↗
PubMedDate not supplied

Effects of hyperthermal stress on the fibrinolytic system.

The effects of hyperthermal stress on the coagulation and fibrinolytic systems were examined in five healthy subjects who took a 3-min 47 degrees C hot-spring bath. After a 3-min 47 degrees C bath, the sublingual temperature was transiently increased about 1.8 degrees C, returning to the baseline level within 60 min. The plasma level of plasminogen activator inhibitor-1 antigen (PAI-1) was transiently increased 15 min after the start of bathing and returned to the pre-bathing level 360 min later. The plasma levels of tissue plasminogen activator antigen, alpha 2 plasmin inhibitor activity, plasmin-antiplasmin complex, thrombin-antithrombin III complex, and thrombomodulin antigen were not influenced by the bath. The in vivo result correlated well with the in vitro result that PAI-1 was released from cultured endothelial cells by heating. These findings suggest that the increase in plasma PAI-1 level may be due to the direct hyperthermal action of the very hot hot-spring bath on the endothelial cells and that acute hyperthermal stress may decrease the fibrinolytic capacity, leading to the occurrence of thrombotic events.

Adult↗
PubMedDate not supplied

Rearrangements of bcl-1, bcl-2, bcl-6, and c-myc in diffuse large B-cell lymphomas.

Diffuse large B-cell lymphoma (DLBL) is characterized by a marked degree of morphologic and clinical heterogeneity. We studied 137 patients with de novo DLBL for rearrangements of the bcl-1, bcl-2, bcl-6 and c-myc oncogenes by Southern blot analysis. Structural alterations of bcl-1, bcl-2, bcl-6, and c-myc were detected in 21 of 137 (15.3%), 8 of 137 (5.8%), 22 of 137 (16.1%), 14 of 137 (10.2%) patients, respectively. Two cases showed a combination of bcl-1 and bcl-6 rearrangements. Chromosomal analysis was performed in 31 cases of the 137 DLBL. 27 of these showed karyotypic abnormalities, and two had translocations 3q27 involving bcl-6. However, one of two cases had no rearrangement of bcl-6. Patients with rearranged bcl-6 and c-myc tended to have poorer survival than patients with germ-line. Furthermore, bcl-1 and bcl-2 rearrangements tended to have a better outcome, although the above differences were not statistically significant. Rearrangements of the bcl-1, 2, 6, and c-myc gene correlated with the clinical outcome in DLBL and may thus serve as prognostic markers in patients with this form of malignant lymphoma. However, other genetic factors are probably involved in determining prognosis.

Adolescent↗
PubMedDate not supplied

Experimental application of polyvinyl alcohol-silica for small artificial vessels.

Polyvinyl alcohol-silica (PVA-SiO2) composite and heparinized PVA-SiO2 were examined in vitro and in vivo as materials to coat artificial vessels to be used for the replacement of small arteries. PVA-SiO2 was observed to prolong coagulation time and on heparinized PVA-SiO2 surfaces no blood coagulation was noticed after a period of two days using the Lee-White and plasma recalcification methods. After placing non-coated and coated surfaces in contact with blood components in vitro and in vivo, the degree of blood component adhesion was greater in non-coated woven Dacron than in PVA-SiO2 coated Dacron. The degree of adhesion was even less in heparinized PVA-SiO2 coated Dacron. Furthermore, artificial vessels made of these 3 types of materials were used to replace parts of the canine abdominal aorta and were removed one and a half years later. Patency rates were as follows: non-coated 2/7, PVA-SiO2-coated 4/7, heparinized PVA-SiO2-coated 8/12. The inner surfaces of these prostheses were observed with light microscopy and scanning electron microscopy. Intima formation was thinner on the PVA-SiO2 composite surfaces than on the control surfaces. Heparin acted as a local anticoagulant and PVA-SiO2 limited intima formation. This report showed that PVA-SiO2 composite coated surfaces can be effective for small artery replacement due to good tissue affinity and anticoagulability.

Animals↗
PubMedDate not supplied

Significance of heat loss in energetics of left ventricle.

Left ventricular heat loss was examined by measuring the temperatures in the coronary sinus blood, in the aortic blood, and in the left atrial blood by thermistors. The temperature was highest in the coronary sinus blood, in the aortic blood next, and it was the least in the left atrial blood. However, since the aortic blood flow was naturally higher than the coronary sinus blood flow, the heat loss was larger in the left ventricular cavity than in the rest of the chambers. This heat loss was mostly proportional to the magnitude of the changes of both the arterial blood pressure and the aortic blood flow.

Animals↗
PubMedDate not supplied

Coronary circulation, myocardial metabolism and hemodynamics of pacing-induced angina.

The following changes were noted during pacing-induced angina: The coronary sinus blood flow was less than it was during the control period and less than that in the myocardial ischemic group without induced angina. While myocardial oxygen consumption did not increase, myocardial metabolism became anaerobic. The possibility of myocardial dysfunction also was noted.

Adolescent↗
PubMedDate not supplied

Second malignancies after a gastrectomy for gastric cancers: the effects of adjuvant therapies.

Second malignancy after gastrectomy has become one of the important issues in the management of gastric cancer patients. However, the effect of adjuvant therapies has never been surveyed, although there have been many reports on second malignancy after chemotherapy of other malignancies. Between 1979 and 1995, 574 patients with gastric cancer underwent gastrectomies in our department. 563 patients (98.1%) were completely followed-up, and the incidence of second malignancy after gastrectomy was assessed with special emphasis on the effect of adjuvant therapies, namely benefits versus carcinogenesis. The overall postsurgical survival rate was 62.5%, and the survival rate of patients with stage 2-4 cancer was significantly higher in the adjuvant therapy groups than in the surgery alone group. The overall incidence rate of a second malignancy was 3.20% (18/563), including 4 colorectal, 3 liver, 3 head and neck, and 8 other malignancies, and 3.90% (9/231) for the surgery alone group, 1.94% (3/155) for the chemotherapy group, 3.68% (6/163) for the chemoimmunotherapy group, and 0% (0/14) for the immunotherapy alone group. There were no statistical differences in the incidence rates between these 4 groups. The mean duration until the occurrence of second malignancy was 5.1 years for the surgery alone group, 8.6 years for the adjuvant therapy group (9.3 years for chemotherapy and 8.1 years for chemoimmunotherapy; p < 0.1, surgery alone vs. adjuvant therapy). The overall mean actuarial risk of developing a second malignancy was 6% at 5 years and 18% at 10 years. Multivariate analysis demonstrated that chemotherapy decreased the risk of death due to gastric cancer (risk ratio = 0.67, p = 0.017) and the risk of a second malignancy (risk ratio = 0.52, p = 0.261). Oral fluoropyrimidines were found to be particularly effective at decreasing the risk of death due to gastric cancer (risk ratio = 0.66, p = 0.012) and a second malignancy (risk ratio = 0.38, p = 0.136). However, intravenous chemotherapy was demonstrated to have no influence on survival (risk ratio = 0.93, p = 0.692) or a second malignancy (risk ratio = 0.58, p = 0.500). There was no evidence of an increased risk for a second malignancy following adjuvant chemotherapy. Adjuvant chemotherapy with oral fluoropyrimidines was suggested to contribute to the improved survival of patients with stage 2-4 gastric cancer, and to have a decreased the risk of a second malignancy.

Adult↗
PubMedDate not supplied

Human proinsulin gene-transfected Chinese hamster ovary cells secrete immunoreactive insulin.

BACKGROUND: Considering the difficulties in pancreas transplantation, the development of an artificial pancreas can be one of the new approaches. The present study was designed to assess whether or not Chinese hamster ovary (CHO) cells, which were transfected with the human proinsulin (hPI) gene, secrete immunoreactive insulin (IRI) and respond to glucose loading. MATERIALS AND METHODS: A complementary DNA encoding hPI was obtained by polymerase chain reaction amplification from human pancreatic tissue and was inserted into the plasmid pcDNA I/NEO to construct an expression vector for the hPI gene. CHO cells were transfected with hPI gene using lipofectin, and the hPI gene-expressing clones (CHO/I) were selected. RESULTS: Five clones of CHO/I cells, releasing IRI into the culture supernatant, were separated. Immunohistochemistry with a monoclonal antibody demonstrated the IRI in the cytoplasm of CHO/I cells, and transmission electron microscopic examination demonstrated the prominently developed mitochondria, but no secretion granules. ELISA assay demonstrated the secretion of IRI into the culture supernatant of CHO/I, but CHO/I cells did not respond to the glucose loading. When CHO/I cells were transplanted subcutaneously into the back of nude mice, the growing tumors secreted IRI. CONCLUSIONS: These results demonstrate that the hPI gene can be transfected into mammalian cells and function in vivo, and suggest that this kind of gene technology may be applicable in the development of an artificial pancreas.

Animals↗
PubMedDate not supplied

Anticancer chemosensitivity profiles of human breast cancer cells assessed by in vitro DNA synthesis inhibition assay.

The present study was designed to assess the profile of the chemosensitivity of breast cancer cells and to screen effective agents for combination regimens. Chemosensitivity to anticancer agents was assessed by the 3H-thymidine incorporation assay, as the rate of inhibition of DNA synthesis in 145 samples (88 primary and 57 metastatic or recurrent lesions) from 136 patients with breast cancer. The correlations of the anticancer agents with various clinicopathological factors were analysed. The effectiveness of the agents was classified as a rate of inhibition on log scale as follows: highly sensitive (> or = 30%), moderately sensitive (25-30%), slightly sensitive (20-25%), resistant (< 20%). The chemosensitivity of breast cancer showed variations according to tumor location: primary lesions seemed to be slightly sensitive to carboquone (CQ), adriamycin (ADR), and cytosine arabinoside (Ara-C); nodal involvement was moderately sensitive to CQ and slightly sensitive to Ara-C, 5-FU, ADR, mitomycin-C (MMC), and cisplatin (CDDP); malignant effusions were highly sensitive to ADR, moderately sensitive to CQ, and slightly sensitive to Ara-C and CDDP; local recurrences were slightly sensitive to Ara-C, CQ and 5-FU; vincristine (VCR) and nimustine chloride (ACNU), however, seemed to be ineffective against breast cancer. There were significant correlations in chemosensitivity between most agents, but no correlation was found between 5-FU and CDDP, 5-FU and ACNU, MMC and VCR, ADR and CDDP, ADR and VCR, and ADR and ACNU. There were no differences in chemosensitivity between stages of primary lesions or between estrogen receptor-positive and -negative tumors. In 10 patients, simultaneous nodal involvement was more sensitive to the agents than were primary lesions, and the correlation of chemosensitivity to ADR and CQ between such lesions was significant. On the other hand, there was no significant difference or correlation of chemosensitivity between the original lesions and recurrent ones after chemotherapy. The heterogeneity and homogeneity in the chemosensitivity of breast cancer suggested not only the necessity of patient-specific chemotherapy based on a sensitivity assay, but also the usefulness of choosing agents for widely-applicable combination regimens against breast cancer.

Adult↗
PubMedDate not supplied

Intraperitoneally implanted artificial pancrease with transkaryotic beta-cells on microcarrier beads in a diffusion chamber improves hyperglycemia after 90% pancreatectomy in rats.

BACKGROUND: Considering the difficulties in pancreas transplantation, the development of an artificial pancreas would be of great value. We have established a transkaryotic artificial beta-cell line, CHO/I, produced by transfecting the human proinsulin gene into the Chinese hamster ovary (CHO) cell line. The present study was designed to assess the value of an artificial pancreas using a diffusion chamber containing CHO/I cells. MATERIALS AND METHODS: Wistar rats rendered diabetic by 90% pancreatectomy were treated by implanting a diffusion chamber containing CHO/I cells cultured on microcarrier beads. RESULTS: The diffusion chamber containing microcarrier beads produced 100-folds more CHO/I cells than the chamber alone, as calculated from the secreted IRI in vitro. When diffusion chambers containing CHO/I cells on microcarrier beads were implanted into the peritoneal cavity of the 90% pancreatectomized rats, the fasting serum IRI level increased and the fasting blood glucose decreased to the normal level for 12 weeks. An intraperitoneal glucose tolerance test demonstrated, however, that the diffusion-chamber-implanted rats did not respond to glucose loading. CONCLUSION: An artificial pancreas using a diffusion chamber containing human proinsulin gene transfected cells might be a promising model for future clinical application.

Animals↗
PubMedDate not supplied

Reduced invasiveness and metastasis of Chinese hamster ovary cells transfected with human interleukin-17 gene.

Human IL-17 (hIL-17) stimulates epithelial, endothelial, fibroblastic cells and macrophages to secrete various cytokines. The present study was designed to assess the effects of the transfection of the hIL-17 gene in Chinese hamster ovary (CHO) cells. A complementary DNA (cDNA)-encoding hIL-17 was obtained by polymerase chain reaction (PCR) amplification from human CD4+ T-cell cDNA and inserted into the plasmid pRc/CMV to construct an expression vector for hIL-17. CHO cells were transduced with hIL-17 DNA-carrying cytomegalovirus (CMV)-based retroviral vectors. A clone with a high mRNA expression of hIL-17 (CHO/IL-17) was selected by Northem blotting. There was no significant difference in the in vitro growth of cells among parent CHO cells, vector-only transfected cells (CHO/neo) and CHO/IL-17 cells. A Matrigel invasion chamber assay, however, demonstrated significantly lower invasiveness by CHO/IL-17 cells than by either the parent CHO or the CHO/neo cells. There was no difference in the in vivo growth among the cells, when subcutaneously transplanted into nude mice. When injected into the tail vein, however, the number of metastatic nodules in the lungs of CHO/IL-17-injected mice was significantly smaller than that of CHO- or CHO/neo-injected mice. Furthermore, NK activity of spleen cells was significantly higher in nude mice transplanted with CHO/IL-17 cells than in mice transplanted with parent CHO or CHO/neo cells. In conclusion, the hIL-17-gene-transfected CHO cells showed a significantly lower metastatic potential to the lung by directly modulating the invasiveness and metastasis of CHO cells as well as by enhancing NK activity.

Animals↗
PubMedDate not supplied

Induction of tumor-specific antitumor immunity after chemotherapy with cisplatin in mice bearing MOPC-104E plasmacytoma by modulation of MHC expression on tumor surface.

Chemotherapy sometimes results in induction of specific antitumor immunity. We investigated the mechanisms responsible for the induction of antitumor immunity in mice bearing MOPC-104E plasmacytoma after chemotherapy with cisplatin (CDDP), especially the effects of CDDP on the expression of MHC on the tumor surface. BALB/c mice were subcutaneously (s.c.) inoculated with MOPC-104E cells on day 0, then intravenously (i.v.) treated with CDDP at 3.6 mg/kg on day 7. The tumors disappeared completely on day 35 and the mice rejected a second challenge with MOPC-104E, but did not reject syngeneic Meth-A fibrosarcoma. The tumors did not regress, however, when MOPC-104E was s.c. transplanted in nude mice, or when anti-T-cell monoclonal antibodies were i.v. injected into BALB/c mice before CDDP treatment on day 6. To determine which of the mice or tumor were affected by CDDP, BALB/c mice were inoculated with CDDP-treated (12.5 micrograms/ml for 3 hours in vitro) MOPC-104E cells on day 0, 7 and 14. The potential to reject MOPC-104E was lower in mice immunized with ethanol-treated MOPC-104E cells than in those immunized with CDDP-treated cells. CDDP-treated or -untreated MOPC-104E cells ultrasonicated and fractionated into soluble and insoluble fractions by centrifuging, also induced antitumor immunity. Flow cytometry demonstrated that the expression of MHC-class-I antigens H-2Dd and H-2Kd was enhanced after CDDP-treatment, but that of class-II antigens I-Ad and I-Ed was not, suggesting that CDDP induced tumor-specific antitumor immunity by enhancing the expression of MHC-class-I antigens.

Animals↗
PubMedDate not supplied

Age-related trend for blood pressure circadian rhythm in normotensive healthy subjects: estimates provided by the clinospectror method.

The present study investigates how blood pressure (BP) circadian rhythm (CR) changes in its rhythmic properties as a function of chronological age in normotensive healthy subjects (NHS). The age-related trend for BP CR was investigated via the Clinospectror method, a periodic-linear analysis of regression for rhythmic parameters. The study was performed on 437 NHS (219 males and 218 females, ranging in age from 1 year to 102 years), who were monitored in their 24-h BP via a noninvasive automated recorder. An age-related trend was detected for the three properties of BP CR, i.e., mesor (M), amplitude (A) and acrophase (cent). Such a trend was positive for M and A, and negative for cent. According to the clinospectrometric formula, the BP CR can be classified as a "dianaclinous rhythm", i.e., a rhythm which increases in its oscillatory level and extent with advancing years. The documented age-related trend for the rhythmic properties suggests that the biological clock which regulates the BP CR in human beings undergoes a resetting of its mechanisms of tonic, amplitude and phasic modulation as a function of chronological age. The readjustment of the pressure clock may be regarded as one of the physiological features which characterize the aging process in human beings.

Adolescent↗
PubMedDate not supplied

Plant polysaccharide PSK: cytostatic effects on growth and invasion; modulating effect on the expression of HLA and adhesion molecules on human gastric and colonic tumor cell surface.

PSK is a plant polysaccharide widely used for cancer immunotherapy in Japan and other Asian countries. It is considered that its antitumor effect is derived from its immunomodulating activity on the tumor-bearing host. The present study was designed to assess the direct action of PSK on in vitro proliferation and invasion of human KATO-3 gastric and Colo205 colonic cancer cell lines, and the expression of surface molecules such as HLA and adhesion molecules on these cells. The in vitro growth of KATO-3 cells was significantly inhibited by 100 micrograms/ml of PSK 48 hrs after culture initiation, and that of Colo205 was significantly inhibited by 10 and 100 micrograms/ml of PSK 24 hrs after culture initiation. The effect of PSK on the in vitro invasion of the tumor cells, assessed with a Matrigel invasion chamber, revealed that invasion of KATO-3 and Colo205 cells was inhibited by more than 10 micrograms/ml and more than 5 micrograms/ml of PSK, respectively. KATO-3 cells expressed HLA-ABC, HLA-A2/A28, HLA-DR very weakly, at almost baseline levels, but HLA-B27, B2-microglobulin and HLA-DQ were expressed at various levels. After treatment of KATO-3 cells with PSK, the expression of HLA-B27 and beta 2-microglobulin was significantly enhanced. Colo205 cells expressed all class-I antigens tested in this study at different levels, but class-II antigens at almost baseline levels. PSK also enhanced the expression of class-I antigens on Colo205 cells. ICAM-1 was expressed on KATO-3, but not on Colo205. The expression of ICAM-1 was enhanced to a greater extent by treatment with 10 micrograms/ml than with 100 micrograms/ml of PSK. Adenocarcinoma antigen AC-81 was strongly expressed on both cell lines, but PSK-treatment significantly enhanced its expression. These results suggested that enhancement of HLA class-I expression on tumor cells after PSK treatment may be one of the mechanisms responsible for the induction of anti-tumor immunity by PSK.

Antineoplastic Agents, Phytogenic↗