Biomedical subjects

H Wada

Publications and source records attributed to H Wada.

At least 253 records · Page 14Linked to original sources

PubMed1999

Selectively induced high MRP gene expression in multidrug-resistant human HL60 leukemia cells.

A subclone HL60/DOX was selected from a human leukemic HL60 cell line for resistance to doxorubicin (DOX) by exposure to stepwise increasing concentrations of the drug and coexposure to a potential P-glycoprotein (P-gp) inhibitor, cepharanthine (a biscoclaurine alkaloid). Compared with the parent HL60 cells, the HL60/DOX cells were 13.0-fold more resistant to DOX and showed multidrug-resistant (MDR) phenotype characterized by 4.6-fold, 2.3-fold, and 5.7-fold cross-resistance to vincristine, pirarubicin, and etoposide, respectively, but no cross-resistance to alkylating agent, cisplatin. Immunocytochemical analyses using the specific monoclonal antibody, MRPr1, and quantitative analyses using a competitive reverse transcription-polymerase chain reaction (CRT-PCR) confirmed overexpression of MRP gene products (about 8-fold determined by CRT-PCR) in this resistant clone. The P-gp expression was not detectable by the monoclonal antibody, C219, in the HL60/DOX cells, and that was consistent with extremely low levels of mdr1 mRNA expression determined by CRT-PCR in this clone. Drug accumulation and efflux studies demonstrated the significantly increased efflux rate of DOX compared to the parent HL60 cells. This enhancement of DOX efflux was reversed by the addition of 10 microM verapamil. To investigate the additional underlying mechanisms contributing to MDR phenotype in the HL60/DOX cells, the levels of DNA topoisomerases (Topo) including Topo I, Topo IIalpha, and Topo IIbeta, and gamma-glutamylcystein synthetase (y-GCS) expression were determined using CRT-PCR techniques. Normal expression of each enzyme at the transcriptional level was demonstrated in this resistant clone. Southern blot analysis of the gene organization in the HL60/DOX cells revealed the amplification of MRP gene. These results indicate that alteration of the drug accumulation from enhanced efflux appears to be a major mechanism(s) of MDR phenotype and attributable to high levels of MRP expression in the HL60/DOX cells. Overexpression of MRP in this clone is regulated by the genomic amplification of DNA and increased levels of the MRP mRNA, independently with the normal expression of Topo I, Topo IIalpha, Topo IIbeta, or gamma-GCS.

ATP-Binding Cassette Transporters↗

PubMed1999

Postoperative adjuvant chemotherapy with PVM (Cisplatin + Vindesine + Mitomycin C) and UFT (Uracil + Tegaful) in resected stage I-II NSCLC (non-small cell lung cancer): a randomized clinical trial. West Japan Study Group for lung cancer surgery (WJSG).

OBJECTIVE: The West Japan Study Group For Lung Cancer Surgery (WJSG) conducted a randomized controlled trial in order to assess the usefulness of adjuvant chemotherapy for NSCLC. METHODS: Patients with completely resected NSCLC (stages I and II) were enrolled in the trial. These patients were randomized into two groups: a surgery alone group; and a chemotherapy group which received intravenous administration of two courses of 4-week PVM chemotherapy (80 mg/m2 of Cisplatin on day 1, 2-3 mg/m2 of Vindesine on day 1 and/or day 8, and 8 mg/m2 of Mitomycin C on day 1), after which they took 400 mg/day of UFT (Uracil + Tegaful) orally for 1 year. RESULTS: Among 229 patients registered for the study from August 1988 to July 1990, 225 were available cases (116 patients in the surgery alone group, and 109 patients in the chemotherapy group). No bias in prognostic factors could be found between the two groups. The 5-year survival rate was 71.1% for the surgery-alone group and 76.8% for the chemotherapy group with no significant difference observed. However, subset analysis demonstrated that PVM therapy improved the post operative survival of pT1N0 patients (the 5-year survival rate: 75.3% for the surgery alone group, and 90.7% for the chemotherapy group P<0.05). CONCLUSIONS: It is interesting to find that among pT1N0 patients, who were not regarded as a target of chemotherapy, those receiving chemotherapy showed significantly better prognostic results. These findings suggest the necessity of further studies on the adjuvant chemotherapy, even in the early stages.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1999

Activation of human T lymphocytes by ganglioside-containing liposomes.

We investigated the in vitro stimulatory effect of ganglioside (GM3, GD1a, GD1b, GT1b, or GQ1b)-containing liposomes on human immune cells. The effect of ganglioside-containing liposomes on the concentration of cytoplasmic free calcium ions ([Ca2+]i) in human immunocytes was examined using the confocal laser fluorescence microscopic method. The GD1a- and GT1b-containing liposomes significantly increased [Ca2+]i of human T lymphocytes compared with the GM3-, GD1b- and GQ1b-containing ones. The response of CD8+ and CD4+ cells was significantly higher than that of CD20+ cells. Our results show that the increase in [Ca2+]i may be caused by not the number of sialic acids contained in the gangliosides but the conformation of the sialic acid moiety to protrude exteriorly from the liposomal membrane surface, and that a sort of receptor recognizing the sialic acid moiety exists on human T lymphocytes (both CD8+ and CD4+ cells), which may be involved in the activation of the cells. The present results are almost the same as those obtained for the rat T lymphocyte system previously reported. This clearly confirms that a sort of ganglioside surely stimulates T lymphocytes directly, which is not species-specific but conserved in humans and rats among animal species.

Animals↗

PubMed1999

Alteration of p16 and p15 genes in human uterine tumours.

The roles of the p16 and p15 inhibitor of cyclin-dependent kinase tumour suppressor genes were examined in human uterine cervical and endometrial cancers. p16 mRNA, examined by reverse transcription polymerase chain reaction (RT-PCR), was significantly reduced in five of 19 (26%) cervical and four of 25 (16%) endometrial tumours. Reduced expression of p16 protein, detected by immunohistochemistry, occurred even more frequently, in nine of 33 (27%) cervical and seven of 37 (19%) endometrial tumours. Hypermethylation of a site within the 5'-CpG island of the p16 gene was detected in only one of 32 (3%) cervical tumours and none of 26 endometrial tumours. Homozygous p16 gene deletion, evaluated by differential PCR analysis, was found in four of 40 (10%) cervical tumours and one of 38 (3%) endometrial tumours. Homozygous deletion of p15 was found in three of 40 (8%) cervical tumours and one of 38 (3%) endometrial tumours. PCR-SSCP (single-strand conformation polymorphism) analysis detected point mutations in the p16 gene in six (8%) of 78 uterine tumours (four of 40 (10%) cervical tumours and two of 38 (5%) endometrial tumours). Three were mis-sense mutations, one in codon 74 (CTG-->ATG) and one in codon 129 (ACC-->ATC), both in cervical carcinomas, and the other was in codon 127 (GGG-->GAG) in an endometrial carcinoma. There was one non-sense mutation, in codon 50 (CGA-->TGA), in an endometrial carcinoma. The remaining two were silent somatic cell mutations, both in cervical carcinomas, resulting in no amino acid change. These observations suggest that inactivation of the p16 gene, either by homologous deletion, mutation or loss of expression, occurs in a subset of uterine tumours.

Animals↗

PubMed1999

Thrombotic microangiopathy following allogeneic bone marrow transplantation.

Thrombotic microangiopathy is one of the complications of bone marrow transplantation and is related to other complications such as graft-versus-host disease, veno-occlusive disease, diffuse alveolar hemorrhage, and cytomegalovirus infection. Thrombotic microangiopathy occurred in three out of 12 patients who underwent allogeneic bone marrow transplantation over the past 1 year at our department. We compared the changes in cytokines and other molecules between patients with and without microangiopathy from before conditioning to the early post-transplantation period. All three patients with microangiopathy showed a significant increase of interleukin-12 at the time of leukocyte recovery after transplantation (two-way layout analysis of variance; P < 0.05), while none of the patients without microangiopathy showed an increase of interleukin-12. No significant differences were found between the two groups with respect to the other cytokines and molecules that were tested. These findings suggested that thrombotic microangiopathy might be predicted at an early stage after bone marrow transplantation by detecting an increase of interleukin-12 at the time of leukocyte recovery. The possibility that thrombotic microangiopathy is related to inflammation or autoimmunity was also suggested.

Adolescent↗

PubMed1999

Predicting the severity of graft-versus-host disease from interleukin-10 levels after bone marrow transplantation.

Acute graft-versus-host disease (GVHD) is the most important complication of allogeneic bone marrow transplantation. We investigated the possibility of predicting severe acute GVHD using plasma interleukin-10 levels in 31 patients who underwent allogeneic bone marrow transplantation. In patients with acute GVHD, the interleukin-10 (IL-10) level increased significantly from the aplastic phase through the leukocyte recovery phase after transplantation (P < 0.05, paired t-test). The ratio of the IL-10 level in the aplastic phase to that in the leukocyte recovery phase was significantly correlated with the severity of acute GVHD (P < 0. 05, t-test), and the incidence of grade III or IV disease was significantly increased (P < 0.0001). Since IL-10 antagonizes various other cytokines that induce acute GVHD, determination of the IL-10 level is equivalent to assessing the total production of cytokines promoting GVHD. The ratio of the IL-10 level in the aplastic phase to that in the recovery phase seems to be useful for predicting the subsequent risk of acute GVHD.

Acute Disease↗

PubMed1999

Immunohistochemical assessment of human bone marrow macrophages in hematologic disorders.

Changes in bone marrow macrophages may be associated with abnormal hematopoiesis in various hematologic disorders. We immunohistochemically evaluated the density of macrophages in bone marrow trephine biopsies. In reactive erythroid hyperplasia (hemolytic anemia and megaloblastic anemia), the macrophages slightly increased in density, extending their cytoplasmic processes between hematopoietic cells. In erythroid hypoplasia (pure red cell aplasia), they became rounded and frequently had hemosiderin granules. There was no significant difference in the macrophage density in the hematopoietic area between erythroid hyperplasia and hypoplasia. The macrophages increased in density in myeloproliferative disorders (polycythemia vera, chronic myelogenous leukemia and primary thrombocythemia). In myelofibrosis, some macrophages became extremely elongated along the line of the fibroblastic cells. In contrast, in conditions in which myelopoietic activity is considerably impaired (aplastic anemia, acute leukemia and multiple myeloma), they significantly decreased in density. These results suggest that the morphologic change in bone marrow macrophages is associated with erythropoietic activity and that there is a correlation between macrophage density and myelopoietic activity.

Antibodies, Monoclonal↗

PubMed1999

Flow balance between the left and right cardiac output of an eccentric roller type total artificial heart.

We have made an eccentric roller type total artificial heart (ERTAH). The ERTAH is a positive-displacement device comparable to a DeBakey roller pump. Its left and right outputs are determined by the size of its blood chambers, and the ratio of its left and right output is almost constant. We focused on an interatrial shunt to achieve left-right balance. We have conducted numerical simulation, a mock test, and an acute animal experiment to analyze left-right heart balance during ERTAH operation. Numerical simulation was performed under conditions in which the flow of the left artificial heart was fixed at 6 L/min, the flow of the right artificial heart was varied from 4.8 to 6 L/min, and the interatrial resistance was also varied. The relationship between the interatrial shunt flow rate and the output of the left and right artificial hearts was balanced when the flow of the right artificial heart was at 5.45 L/min. In a mock test, 2 DeBakey roller pumps were connected to the left and right sides of a Donovan mock circulatory system, and an interatrial shunt was created between the inlet ports of the left and right roller pumps. The interatrial resistance of the mock system was varied from 7.7, to 4.3, and to 2.9 mm Hg x min/L when the inner diameter of the interatrial shunt was 6, 8, and 10 mm, respectively. As in the mock test, 2 roller pumps were used to bypass the right and left hearts of a goat weighing 60 kg. The flow rate of the left heart was almost constant (4.7 L/min). The flow of the right heart was approximately 4.1 L/min when the interatrial shunt flow rate was zero. A leading consideration was that the left to left shunt through the bronchial arteries in this goat was approximately 0.6 L/min. In developing the ERTAH, we considered that creating an interatrial shunt between the inlet ports of the ERTAH as well as making a difference between the chamber volumes might be effective in balancing the left-right sides of the artificial heart.

Animals↗

PubMed1999

Clinical application of biodegradable rib connecting pins in thoracotomy.

BACKGROUND: To assess the usefulness in rib reconstruction of biodegradable connecting pins made of polylactide (PLA), PLA rib pins were compared with conventional non-absorbent aluminous ceramic rib pins (alumina rib pins) in terms of their ability for fixing and healing of cut ribs in thoracic surgery. METHODS: There were 13 cases of rib fixation after thoracotomy using PLA rib pins and 11 cases using alumina rib pins, all of which were inserted into the medulla of the stump of the ribs that had been cut at thoracotomy to secure a larger surgical field. The observation period was 6 months after the operation. RESULTS: The degree of vertical shift of the ribs connected with PLA rib pins was significantly reduced compared with the degree using alumina rib pins. In chest radiographs clear zones around the pins, indicating a delay in bone neogenesis, were observed frequently around the alumina rib pins but were absent around the PLA rib pins. Osteosynthesis using PLA rib pins was significantly more favorable than with alumina rib pins. CONCLUSIONS: These results demonstrated that the PLA rib pin was superior to the alumina rib pin for fixing and healing of the cut rib.

Adult↗

PubMed1999

Inhibitory effect of glyburide on thrombin-induced platelet aggregation and phosphoinositide metabolism in normal human platelets.

We previously reported the effects of diet, sulphonylureas or insulin on thrombin-induced platelet aggregation, phosphoinositide metabolism and protein phosphorylation in non-insulin-dependent diabetes mellitus (NIDDM) patients. To clarify the mechanism of glyburide and insulin on platelet function, here we studied the in vitro effects of glyburide and insulin on thrombin-induced metabolic changes using normal human platelets. Platelet aggregation stimulated with <0.5 U/ml thrombin, 0.75-3 microM adenosine diphosphate (ADP) or 1 microg/ml collagen was significantly lower in glyburide-treated platelets, but not in insulin-treated platelets, than in untreated ones (control). Thrombin-induced incorporation of 32P radioactivity into phosphatidic acid (PA) in glyburide-treated platelets was lower than that in control but not in insulin-treated platelets. Phosphorylated proteins of platelets induced by thrombin and 12- O -tetradecanoylphorbol 13-acetate (TPA) in glyburide-treated platelets were suppressed, but not in insulin-treated platelets, compared with control. These results suggest that glyburide induces suppression of thrombin-induced activation of phospholipase C, which mediates hydrolysis of PIP and PIP(2) and production of PA, and subsequently inhibits platelet aggregation.

Journal Article↗

PubMed1999

Mouse glutaredoxin - cDNA cloning, high level expression in E. coli and its possible implication in redox regulation of the DNA binding activity in transcription factor PEBP2.

We have isolated a cDNA encoding glutaredoxin (GRX) from a mouse splenic cDNA library. This cDNA encoded a protein of 107 amino acids with a calculated molecular weight of 11.9 kDa. The deduced amino acid sequence of glutaredoxin in mouse was highly homologous with that in other mammals (81-89%), containing a putative active sequence of -Cys-Pro-Try-Cys-. Recombinant mouse glutaredoxin expressed in E. coli showed glutathione-disulfide oxidoreductase activity with beta-hydroxyethyl disulfide as its substrate, whereas mutant glutaredoxin (Cys 22, Cys 25 to Ser) showed no activity. In electrophoretic mobility shift assay, we proved that wild type GRX, not mutant one, recovered the DNA-binding activity of a transcription factor, PEBP2, oxidized by diamide. This showed that GRX may be involved in the redox regulation of the DNA-binding activity of PEBP2 as is the case with thioredoxin.

Amino Acid Sequence↗

PubMed1999

Secretory leukocyte protease inhibitor (SLPI) concentrations in cervical mucus of women with normal menstrual cycle.

Secretory leukocyte protease inhibitor (SLPI) is a potent inhibitor of human leukocyte elastase. SLPI transcripts in the cervical tissue were detected during the menstrual cycle by reverse transcription-polymerase chain reaction (RT-PCR). Western blot analysis revealed that the intensity of SLPI protein in cervical tissue in the ovulatory phase was stronger than in other phases. Immunohistochemistry using an anti-SLPI polyclonal antibody revealed positive staining in the epithelial cells of the endocervix. Western blot analysis also revealed that SLPI protein was present in the cervical mucus. Again the intensity of SLPI protein in the ovulatory phase was stronger than that in the follicular phase. The SLPI concentrations and SLPI/elastase ratios in the cervical mucus of women in the ovulatory phase were significantly higher than in the follicular and luteal phases. The SLPI and elastase concentrations in the cervical mucus were positively correlated. No significant difference was found in the SLPI serum concentrations of women during the menstrual cycle. These results suggest that production of SLPI from cervical epithelial cells during the ovulatory phase may be important for protection from the effects of elastase.

Adult↗

PubMed1999

Skin flap storage with intracellular and extracellular solutions containing trehalose.

To evaluate and compare the effects of IT-Kyoto (IT-K) solution (intracellular type) and ET-Kyoto (ET-K) solution (extracellular type) on long-term skin flap preservation (from 24-120 hours), Japanese white rabbits were used as an animal model and Euro-Collins (EC) solution was used as a comparative solution. A total of 180 animals were divided randomly into 15 groups (N = 12) for 24, 48, 72, 96, and 120 hours of flap storage in three solutions. The survival rate, weight change, and histological appearance of flaps were compared among the three solutions. The survival rates in the IT-K and ET-K solutions were the same: 100%, 100%, 100%, 92%, and 50% in flaps preserved for 24, 48, 72, 96, and 120 hours, which were higher (p < 0.01 in the 72-, 96-, and 120-hour groups) than those in the EC solution group: 100%, 75%, 33%, 8.3%, and 0%. The flap weight gain in the IT-K and ET-K solution groups was less than that in EC solution group (p < 0.01). Histologically, flaps in the IT-K and ET-K solution groups showed a better appearance than those in the EC solution group. It was concluded that in a rabbit model IT-K and ET-K solutions are superior to EC solution for long-term skin flap preservation, and the safe preservation period for IT-K and ET-K solutions is approximately 96 hours. It was also concluded that the effects of intracellular (IT-K)-type solution and extracellular (ET-K)-type solution on rabbit skin flap preservation are similar.

Animals↗

PubMed1999

Hemostatic markers in Japanese patients undergoing anticoagulant therapy under thrombo-test monitoring.

The objective of this study was to evaluate several molecular markers of hemostasis in 84 patients with hypercoagulable state, treated with warfarin under thrombo-test (TT) monitoring; TT was expressed as percent of control (TT%). In all patients, the average values of international normalized ratio (INR) of prothrombin time (PT;PT-INR) was 1.68+/-0.49; this increase in PT-INR was not, however, significant in patients under TT% monitoring. There were no thrombotic or severe bleeding complications in these patients during a period of 2 years. Plasma levels of thrombin-antithrombin complex (TAT), plasmin-plasmin inhibitor complex (PPIC), D-dimer, and soluble fibrin monomer (sFM) were slightly increased, suggesting that anticoagulant therapy was not completely effective in our Japanese patients based on the values of TT%. Activated partial thromboplastin time, PT-INR, TT% and protein C activity were significantly correlated with the dose of warfarin; fibrinogen, activated thromboplastin, TAT, PPIC, D-dimer, sFM, protein S and thrombomodulin were not significantly correlated with the dose of warfarin. The PT-INR was negatively correlated with TT%, protein C and protein S, and the correlation between PT-INR and TT-INR was better than that between PT-INR and TT%. The range of TT% was not correlated with the plasma levels of TAT, PPIC, D-dimer or sFM, but the range of PT-INR was correlated with the plasma level of TAT, D-dimer and sFM. The percentage of TAT, D-dimer and sFM within normal range was significantly low in patients with high PT-INR. These finding showed that PT-INR is better than TT% for monitoring the anticoagulant therapy with warfarin, and that TT should be expressed as INR. The values of PT-INR should be more than 1.7 during the anticoagulant therapy with warfarin in Japanese patients with high risk of thrombosis.

Adult↗

PubMed1999

Construction of a linkage map of the medaka (Oryzias latipes) and mapping of the Da mutant locus defective in dorsoventral patterning.

Double anal fin (Da) is a medaka with an autosomal semidominant mutation that causes mirror image duplication of the ventral region concentrating on the caudal region. The chromosomal location of the Da gene and its sequence have remained unknown. We constructed a medaka linkage map as a first step to approach positional cloning of the gene. The segregation analysis was performed on the basis of genetic recombination during female meiosis using 134 random amplified polymorphic DNA (RAPD) markers, 13 sequence-tagged sites (STSs), 15 polymorphic sequences from known genes, and the Da gene. One hundred forty-six markers from the above markers segregated into 26 linkage groups. The size of the genome was estimated to be 1776 cM in length. We identified four syntenic regions between medaka and zebrafish (and human) by mapping the known genes and found one of them to be located in close proximity to the Da gene. By mapping the region surrounding the Da gene in high resolution, two markers were detected flanking the Da gene at 0.32 and 0.80 cM. The detected markers providing a vital clue to initiate chromosome walking will lead us to the definite location of the Da gene.

Animals↗

PubMed1999

Expression of thymidylate synthase in human non-small cell lung cancer.

5-Fluorouracil (5-FU) has been used worldwide, and the correlation between its effects and thymidylate synthase (TS) expression has been reported in gastrointestinal malignancy. But the significance of TS expression for 5-FU-based chemotherapy has rarely been reported in non-small cell lung cancer (NSCLC). We investigated surgically resected specimens of 23 consecutive patients with previously untreated NSCLC. We used immunohistochemistry and western blot analysis with anti-TS polyclonal antibody to evaluate the existence of TS, and fluorodeoxyuridine-5'-monophosphate (FdUMP) binding assay to evaluate the enzymic activity of TS. We found that 14 samples (60.9%) were positive immunohistochemically, and that the results of immunohistochemistry closely reflected the enzymic activity measured by FdUMP binding assay (ranging from 1.8 to 56.9 pmol/g protein). These results seem to support our experience that 5-FU and its derivatives are clinically significantly effective as a postoperative adjuvant chemotherapy against NSCLC.

Adult↗

PubMed1999

p53 status predicts the efficacy of postoperative oral administration of tegafur for completely resected non-small cell lung cancer.

Although postoperative adjuvant therapy for non-small cell lung cancer (NSCLC) had not been reported to be effective, it has been reported recently that oral administration of tegafur (1-[2-tetrahydrofuryl]-5-fluorouracil, FT) may improve the postoperative prognosis. In the present paper, to examine whether p53 status affects the efficacy of FT as postoperative adjuvant chemotherapy for NSCLC, a total of 236 consecutive patients with completely resected pathologic stage I-IIIa NSCLC were retrospectively reviewed. p53 status was determined by immunohistochemical staining. For all patients, the 5-year survival rate of patients with FT administration (FT group) was 78.1%, being significantly higher than that (69.1%) of patients without FT administration (control group) (P=0.046). For patients without immunohistochemical evidence of p53 overexpression, the 5-year survival rate in the FT group was 87.1%, being significantly higher than that (74.0%) in the control group (P=0.036). This demonstrates an improvement of postoperative prognosis by FT administration. On the other hand, for patients with p53 overexpression, there was no significant difference in the postoperative prognosis between the FT group and the control group (5-year survival rate 63.2% and 60.1%, respectively; P=0.514), demonstrating that FT administration was not effective for these patients. In conclusion, p53 status may be useful for predicting the efficacy of postoperative adjuvant chemotherapy using FT. A prospective randomized study stratified by p53 status is needed to clarify the effect of postoperative FT administration.

Administration, Oral↗

PubMed1999

Hybrid survival motor neuron genes in Japanese patients with spinal muscular atrophy.

Spinal muscular atrophy (SMA) is a frequently occurring autosomal recessive disease, characterized by the degeneration of spinal cord anterior horn cells, leading to muscular atrophy. Most SMA patients carry homozygous deletions of the telomeric survival motor neuron gene (SMN) exons 7 and 8. In the study presented here, we examined 20 Japanese SMA patients and found that 4 of these patients were lacking in telomeric SMN exon 7, but retained exon 8. In these 4 patients, who exhibited all grades of disease severity, direct sequencing analysis demonstrated the presence of a hybrid SMN gene in which centromeric SMN exon 7 was adjacent to telomeric SMN exon 8. In an SMA family, a combination of polymerase chain reaction and enzyme-digestion analysis and haplotype analysis with the polymorphic multicopy marker Agl-CA indicated that the patient inherited the hybrid gene from her father. In conclusion, hybrid SMN genes can be present in all grades of disease severity and inherited from generation to generation in an SMA family.

Adult↗