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Biomedical subjects

H Wada

Publications and source records attributed to H Wada.

At least 559 records · Page 31Linked to original sources

Hepatocyte growth factor is a potent promoter of mitogenesis in cultured rat visceral glomerular epithelial cells.

Hepatocyte growth factor (HGF) was originally identified as an hepatotrophic factor inducing liver regeneration, and was also recently found to stimulate mitogenesis of various epithelial cells. In the present study, we examined the mitogenic effects of native and recombinant HGF on cells of rat visceral glomerular epithelial cell line (SGE1). Native and recombinant HGF each stimulated DNA synthesis in and growth of SGE1 cells to a remarkable degree. These mitogenic activities were dose-dependent, being detectable at 2.5 ng/ml and maximal at 20 ng/ml. Over 30% of SGE1 cells tested were shifted to S-phase by HGF alone, as judging by labeling index values. DNA synthesis stimulated by native or recombinant HGF was high at low SGE1 cell density and was strongly suppressed at high cell density. DNA synthesis in and growth of SGE1 cells were stimulated more strongly by recombinant HGF than by native HGF. In addition, the effects of recombinant HGF and epidermal growth factor were additive, while transforming growth factor-beta 1 strongly inhibited the stimulation of DNA synthesis by recombinant HGF. These findings suggest that HGF may play a role in controlling visceral glomerular epithelial cell growth.

Animals↗

Uniquely higher incidence of isolated or combined deficiency of band 3 and/or band 4.2 as the pathogenesis of autosomal dominantly inherited hereditary spherocytosis in the Japanese population.

To clarify the pathogenesis of hereditary spherocytosis (HS), red cell membrane protein components were analyzed by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) with a 3.5-17% exponential gradient according to the method of Fairbanks et al. and of Laemmli in 47 HS cases from 32 unrelated Japanese families. The relative contents of each membrane protein fraction, which was stained by Coomassie blue, were expressed as their ratios to those of total membrane proteins. The density of each band of red cell membrane proteins in 47 HS patients was compared to that in 10 normal controls or in 4 high-reticulocyte controls. Various isolated or combined deficiencies of membrane proteins in these HS patients were detected by identifying the amounts of membrane proteins, which were > 1 S.D. (91%) or 2 S.D. (53%) of the mean values of normal controls, and > 1 S.D. (100%) or 2 S.D. (98%) of those of high-reticulocyte controls. Contrary to the commonly held belief that most of the autosomal dominantly-inherited HS demonstrate isolated or combined deficiency of ankyrin (ANK) and/or spectrin (SP), a much lower incidence of isolated or combined deficiency of SP and/or ANK was observed in these Japanese HS patients; 19% (> 1 S.D.) or 12% (2 S.D.) compared to normal controls, or 2% (1 S.D.) or 4% (2 S.D.) compared to high-reticulocyte controls. Instead, the incidence of isolated or combined deficiency of band 3 (B3) and/or band 4.2 (B4.2) was markedly elevated in these Japanese HS patients; 50% (1 S.D.) or 39% (2 S.D.) compared to normal controls, or 78% (1 S.D.) or 88% (2 S.D.) compared to high-reticulocyte controls. Other combined deficiencies were also observed, but the incidence was much lower. Therefore, distinct characteristics, i.e., higher incidence of isolated or combined deficiency of B4.2 and/or B3 with much lower incidence of ANK and/or SP deficiency, were observed in Japanese HS patients.

Anion Exchange Protein 1, Erythrocyte↗

[Simultaneous determination of catecholamines, serotonin, and their precursors and metabolites in body fluid by an HPLC system with multi-electrode electrochemical detector].

We have developed two HPLC systems for the simultaneous determination of CA, 5-HT and their precursors and metabolites in human body fluid. One system consisted of two reversed-phase columns, a column switching device, a pair of electrodes for elimination of interferents and two sets of new electrochemical detectors with four electrodes. Using this system, adequate separation of peaks for 17 kinds of CA, 5-HT and their related metabolites in a standard solution required only 17 min. NE, MHPG, DOPAC, 5-HIAA, HVA and TRP levels in cerebrospinal fluid (CSF) were determined without any pretreatment of the CSF samples. The concentrations of DOPAC, 5-HIAA and HVA in CSF were significantly lower in Alzheimer's disease, vascular dementia and Parkinson's disease than in the controls. The other system was developed for determination of CA acidic metabolites and 5-HIAA in human urine. This system consisted of a mixed-mode column (C18/anion) and 8-channel electrochemical detector with isocratic elution of citrate buffer. Detection limits, precision and analytical recoveries of this method were satisfactory for clinical use.

Aged↗

Red cell membrane disorders in the Japanese population: clinical, biochemical, electron microscopic, and genetic studies.

Based on studies on 610 cases of hereditary red cell membrane disorders, the characteristic features of the incidence of these disorders in the Japanese population are described. These patients were screened by a protocol on red cell morphology (scanning electron microscopy), on red cell membrane proteins (sodium dodecylsulfate polyacrylamide gel electrophoresis, and kinetics of membrane proteins), biophysical studies (ektacytometry, mechanical stability and fluorescence recovery after the photobleaching method), membrane transport (sodium influx and efflux, and anion transport), gene analysis (spectrins, band 4.2 and band 3), surface markers (blood type antigens and sialic acid content), and development and expression of membrane proteins (using a two-phase liquid culture system). Among the molecular abnormalities detected, alpha-spectrin mutation appeared rare (only one family with spectrin alpha I/74), as opposed to two beta-spectrin mutations in Japan out of seven worldwide cases. Two unrelated kindreds with a chromosomal abnormality; that is, del (8) (p11.2-p21.1), were found that involved the possible contribution of ankyrin to the pathogenesis of hereditary spherocytosis. Anomalies of a transmembrane domain of band 3 were detected in two independent kindreds with impaired anion transport. Among 16 HE patients, 13 cases were partially band 4.1 deficient. Complete band 4.2 deficiency of the Nippon type (GCT-->ACT at codon 142 in band 4.2 gene) was observed in 17 cases of 13 unrelated kindreds. Other forms of band 4.2 deficiency without the mutation were also detected in three kindreds. Band 7 deficiency was found in seven cases with hereditary stomatocytosis independent of the presence or absence of cation transport abnormalities. A relatively high incidence of hereditary high red cell membrane phosphatidylcholine hemolytic anemia was disclosed by the analysis of red cell membrane lipids.

Anemia, Hemolytic, Congenital↗

Inhibition of reperfusion injury by human thioredoxin (adult T-cell leukemia-derived factor) in canine lung transplantation.

Human thioredoxin, which was previously recognized as adult T-cell leukemia-derived factor, has many physiologic activities, one of which is a radical scavenger effect. Its ability to reduce reperfusion injury was assessed in vivo in a canine lung transplantation model. In 19 dogs, left lung allotransplantation was performed after 100 minutes of warm ischemia. The function of the transplanted lung was assessed after clamping of the contralateral pulmonary artery. In the human thioredoxin group (n = 6), human thioredoxin 30 mg/kg was given to the recipients during reperfusion. In the N-acetylcysteine group (n = 5), N-acetylcysteine 150 mg/kg, known as a radical scavenger, was given in the same manner. In both groups, arterial oxygen tension was significantly higher than in the control group (n = 8). In the human thioredoxin group, peak inspiratory pressure was significantly lower than in the control group. Macroscopic and microscopic examinations showed an almost normal appearance of the lung tissues in the human thioredoxin and N-acetylcysteine groups, in contrast to the abnormal findings in the control group. Thus it would appear that human thioredoxin has a protective effect on transplanted lungs, as does N-acetylcysteine, and that its action may be a radical scavenger effect.

Animals↗

Factor VII Mie: homozygous asymptomatic type I deficiency caused by an amino acid substitution of His (CAC) for Arg(247) (CGC) in the catalytic domain.

We found hereditary factor VII deficiency in a clinically asymptomatic family, and characterized their factor VII gene and the abnormal molecule using recombinant DNA techniques. The propositus was a 45-year-old woman who was noted to have a prolonged prothrombin time. The level of factor VII antigen of the patient was 25.9% of that of normal individuals and the level of factor VII activity was 28% and 24%, when tested using rabbit brain tissue factor and human placental tissue factor in a one-stage clotting assay, respectively. Two of her sisters had almost the same reduced levels of factor VII antigen and activity, and her parents who are first cousins, a son, a daughter and a niece had moderately reduced leves of both factor VII activity and antigen. To identify the mutation site, all the coding exons and exon-intron boundaries of the factor VII gene of the propositus were amplified using the polymerase chain reaction (PCR), then subcloned and sequenced. One missense mutation (G to A) was identified in exon VII of the gene resulting in an amino acid substitution of His(CAC) for Arg(247)(CGC) in the gene product. PCR using a mutagenic primer to introduce a new ApaL I site into the mutant allele of the patient's factor VII gene revealed that this allele was inherited in the affected individuals in the pedigree. Transient expression assays using BHK cells transfected with an expression vector containing the mutant factor VII cDNA suggested that this mutation leads to factor VII deficiency by impairing secretion of the mutated factor VII.(ABSTRACT TRUNCATED AT 250 WORDS)

Base Sequence↗

[Adjuvant chemotherapy for non-small cell lung cancer. WJSG: West Japan Study Group for Lung Cancer Surgery].

Surgery is the treatment of choice for non-small cell lung cancer (NSCLC). But even for potentially curative resection, patients often die of relapse, and five-year survival rates are about 70 percent even for stage I patients. Hence, considering the necessity of post-operative adjuvant chemotherapy, many comparative trials have been undertaken internationally as well. It is important to undertake randomized comparative trials with the survival endpoint, comparing with surgery alone, and to assess the efficacy of adjuvant chemotherapy. Cisplatin-based regimens, which are effective for anti-tumor results as a surrogate endpoint, are used routinely in adjuvant settings. However, the reliability of these adjuvant trials is not yet verified at present. This paper reports on the adjuvant chemotherapy results for NSCLC patients who had undergone a completely curative resection, considering QOL (Quality of Life) and immunity.

Antineoplastic Combined Chemotherapy Protocols↗

Electron microscopic and physicobiochemical studies on disorganization of the cytoskeletal network and integral protein (band 3) in red cells of band 4.2 deficiency with a mutation (codon 142: GCT-->ACT).

The role of band 4.2 deficiency in the pathogenesis of red cell membrane dysfunctions was studied in seven unrelated patients with complete band 4.2 deficiency with a point mutation (142 GCT-->ACT; 142 Ala-->Thr) on the cDNA of the band 4.2 gene. Two major types of abnormalities were detected in these patients; (A) abnormalities of the cytoskeletal network in the horizontal dimension, and (B) abnormalities of band 3 in the vertical dimension. Electron microscopy by the surface replica method and the quick-freeze deep-etching method demonstrated the markedly impaired cytoskeletal network (a disorganized cobblestone pattern, uneven distribution of junctional units, and the appearance of bulky aggregates after heat treatment). Ektacytometry showed a markedly decreased red cell deformability especially at 48 degrees C, although the cytoskeletal proteins themselves were essentially normal with normal mechanical stability of the Triton-shells. Electron microscopy by the freeze fracture method revealed a decreased number and a random distribution of intramembrane particles (IMPs) with a shift of the IMPs to a larger size. Fluorescence recovery after photobleaching studies on band 3 indicated the marked increase of its mobile fraction. The extractability of band 3 by Triton X in vitro was markedly enhanced, although the physico-biochemical properties of band 3 itself (the cleavage pattern of band 3 fragments, and the binding properties of band 3 to band 4.2 or ankyrin) were basically normal. These findings demonstrate that band 4.2 plays a crucial role in the maintenance of the normal structure and functions of both the cytoskeletal and integral proteins (band 3).

Anion Exchange Protein 1, Erythrocyte↗

[Plasma level of various markers in patients with thrombotic thrombocytopenic purpura].

We examined various markers in 17 patients with thrombotic thrombocytopenic purpura (TTP), 13 with red cell fragmentation syndrome (RCFS) induced by mitomycin C, and 36 with RCFS caused by disseminated intravascular coagulation (DIC). A platelet activating factor and decrease of von Willebrand factor were frequently observed in patients with TTP, but were not in those with RCFS due to either mitomycin C or DIC. Since increased vascular endothelial cell markers and decreased MTT assay were observed in patients with TTP, it is considered that vascular endothelial cell injury is associated with patients with TTP. The increased plasma cytokines and the hypercoagulable and hypofibrinolytic state indicates that the vascular endothelial cell injury might be caused by microthrombus or activated immune system. Although patients with TTP were treated with plasma exchange, anti-platelet therapy, and high dose steroid therapy, the mortality was still high.

Adolescent↗

Effects of newly developed solutions containing trehalose on twenty-hour canine lung preservation.

Trehalose is a nonreducing disaccharide that stabilizes the cell membrane under various stressful conditions. A previous study demonstrated that trehalose was effective in 12-hour canine lung preservation. We have developed new preservation solutions containing trehalose: an extracellular type ET-Kyoto solution (Na 100 mmol/L, K 44 mmol/L) and an intracellular type IT-Kyoto solution (Na 20 mmol/L, K 130 mmol/L). The composition of these solutions is identical except for the electrolyte content. We examined their efficacy in 20-hour lung preservation. Canine lungs were flushed with ET-Kyoto (group A, n = 6), with IT-Kyoto and prostaglandin E1 (25 micrograms/kg) (group B, n = 6), or with Euro-Collins solution and prostaglandin E1 (25 micrograms/kg) (group C, n = 7), and stored for 20 hours at 4 degrees C. Left lung transplantation was performed and evaluated for up to 130 minutes. The flush time was similar in the three groups. Arterial oxygen tensions (inspired oxygen fraction = 0.5) in group A were uniformly excellent (303.3 +/- 7.0 mm Hg 70 minutes after reperfusion and 303.0 +/- 19.6 mm Hg 130 minutes after reperfusion) and significantly higher than in group B (202.6 +/- 32.0 mm Hg, p < 0.05, and 197.8 +/- 44.0 mm Hg, p = 0.054, respectively) or group C (185.9 +/- 23.0 mm Hg, p < 0.01, and 155.7 +/- 36.3 mm Hg, p < 0.05, respectively). Peak inspiratory pressure in group A was significantly lower than in groups B and C (p < 0.05). Wet/dry weight ratio in group A was significantly lower than in groups B (p < 0.05) and C (p < 0.01). Histologic and scanning electron microscopic examinations showed better preservation in group A than in groups B and C. We conclude that ET-Kyoto is superior to IT-Kyoto and to Euro-Collins solution for 20-hour lung preservation.

Animals↗

Enhanced tissue factor activity and plasminogen activator inhibitor-1 antigen in human umbilical vein endothelial cells incubated with lipoproteins.

The expression of tissue factor (TF) and plasminogen activator inhibitor (PAI)-1 was induced in cultured human umbilical vein cells (HUVEC) by very low density lipoprotein (VLDL). VLDL had a strong capacity for augmenting the expression of TF and PAI-1, while the capacity of LDL or high density lipoprotein (HDL) in this regard was very weak. VLDL and LDL also elevated TF activity in monocyte culture medium (VLDL, LDL) and the conditioned medium markedly elevated TF and PAI-1 production in HUVEC compared with directly added lipoproteins. These findings indicated that lipoproteins affect both monocyte-macrophages and endothelial cells, and that they cause a hypercoagulable-hypofibrinolytic state. It is thus possible that hyperlipidaemia could be a direct risk factor for thrombotic disease even if atherosclerotic lesions are not present.

Cells, Cultured↗

[MECHOP-BM chemotherapy in the treatment of non Hodgkin's lymphoma].

Twenty patients with previously untreated advanced aggressive or relapsed or refractory non-Hodgkin's lymphoma were treated with the MECHOP-BM regimen (MCNU, etoposide, cyclophosphamide, adriamycin, vincristine, prednisolone, bleomycin and methotrexate). Of the 18 patients treated with the MECHOP-BM, the response rate was 78% and complete response (CR) was attained in 33%. Among these CR patients, one patient relapsed, but the other patients continued to show CR (59-243 days, medium 178 days). The most serious toxicity attributed to MECHOP-BM therapy was leukopenia. The mean white blood cell count dropped to 1,300/microliters, and only therapy could be useful in the treatment for patients with untreated aggressive and advanced stage of non-Hodgkin's lymphoma as well as salvage therapy of relapsed cases.

Adolescent↗

[Clinical study of fluconazole-injectable and -granules in pediatric patients].

In this study, we have investigated the clinical effectiveness of fluconazole (FLCZ) given intravenously or orally to pediatric patients with systemic fungal infections. FLCZ was administered intravenously to two patients with acute leukemia (multiple hepatosplenic candidiasis and aspergillosis) and orally to two mycosis complicated with neuroblastoma and aplastic anemia, respectively. Clinical efficacies were excellent and no side effects were observed in any patients. Pharmacokinetic analysis in 6 neonates revealed that the plasma half-life is 37-41 hours after administration of single dose of intravenous infusion of 3 mg/kg of FLCZ.

Administration, Oral↗

High-dose irradiation prevents rejection of canine tracheal allografts.

We investigated the possibility of immunosuppressant-free transplantation of the trachea using high doses of 60Co gamma irradiation of the graft before transplantation. Twenty mongrel dogs were used. Five rings of the trachea were removed from the donors and irradiated with 60Co gamma rays. Five corresponding rings were removed from the thoracic trachea of the recipient dogs, and the irradiated trachea was transplanted. Five animals were placed in each of four dosage groups: group A, no irradiation; group B, 20,000 cGy; group C, 50,000 cGy; and group D, 100,000 cGy. The anastomotic site and graft were covered with a pedicled greater omentum graft. No immunosuppressants were given. In group A, all the animals died within 1 month of tracheal stenosis caused by graft rejection. In groups B and C, one animal in each group survived for a long period, but all the others died of tracheal stenosis caused by graft rejection. In group D (100,000 cGy), the graft became incorporated into the recipient tissue in four of the five animals, and three are still alive (more than 1 year later). These findings indicate that allotransplantation of the trachea without the use of immunosuppressants is possible with pretransplantation irradiation of the graft at the dose of 100,000 cGy.

Animals↗

A novel point mutation (G-1 to T) in a 5' splice donor site of intron 13 of the dystrophin gene results in exon skipping and is responsible for Becker muscular dystrophy.

The mutations in one-third of Duchenne and Becker muscular dystrophy patients remain unknown, as they do not involve gross rearrangements of the dystrophin gene. We now report a defect in the splicing of precursor mRNA (pre-mRNA), resulting from a maternally inherited mutation of the dystrophin gene in a patient with Becker muscular dystrophy. This defect results from a G-to-T transversion at the terminal nucleotide of exon 13, within the 5' splice site of intron 13, and causes complete skipping of exon 13 during processing of dystrophin pre-mRNA. The predicted polypeptide encoded by the aberrant mRNA is a truncated dystrophin lacking 40 amino acids from the amino-proximal end of the rod domain. This is the first report of an intraexon point mutation that completely inactivates a 5' splice donor site in dystrophin pre-mRNA. Analysis of the genomic context of the G-1-to-T mutation at the 5' splice site supports the exon-definition model of pre-mRNA splicing and contributes to the understanding of splice-site selection.

Adult↗

Effects of trehalose in canine lung preservation.

BACKGROUND: The effect of trehalose on the preservation of canine lungs was studied with the use of Euro-Collins solution (ECS). METHODS: In group 1, five lungs were perfused and preserved with a modified ECS in which trehalose (35.0 gm/L) was used instead of glucose. In group 2, six lungs were perfused and preserved with a modified ECS in which glucose was replaced by 70.0 gm/L trehalose. In group 3, six lungs were perfused and preserved with ECS. After preservation for 12 hours, left lung transplantation was performed. RESULTS: The PaO2 values in groups 1 and 2 at 130 minutes after reperfusion were 264.9 and 257.5 mm Hg, respectively. These PaO2 values were significantly higher than the corresponding PaO2 value in group 3 (114.8 mm Hg). All the transplanted lungs in groups 1 and 2 had normal structures on histologic examination, whereas five of the group 3 lungs showed severe pulmonary edema. CONCLUSIONS: These findings show that trehalose is effective in the preservation of lungs for 12 hours.

Animals↗