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Biomedical subjects

Y Ota

Publications and source records attributed to Y Ota.

At least 127 records · Page 7Linked to original sources
PubMed1995

[Anesthesia for removal of a large hepatoma under separated hepatic circulation].

A large hepatoma was removed under isolated hepatic perfusion. Hepatic circulation was separated from systemic circulation by clamping inferior vena cava, potal vein and hepatic artery. Lactated Ringer solution at 4 degrees C was perfused through potal vein, and disposed through the isolated part of inferior vena cava. Blood in proximal part of potal vein and right femoral vein was shunted to right axillary vein using a centrifugal pump. Prothrombin time and activated partial thromboplastin time were prolonged to more than 200 seconds and 300 seconds, respectively, 50 minutes after the commencement of isolated hepatic circulation. They recovered to normal ranges 115 minutes after the declamping, by injection of fresh frozen plasma. On clamping of the inferior vena cava, superior vena cava pressure was elevated and cardiac output decreased. When declamped, an excessive hemorrhage from the cross section of the liver was observed. It took 30 minutes for the systolic blood pressure to recover to 80 mmHg by rapid blood transfusion (150 ml.min-1). The hepatic perfusion with chilled lactated linger solution reduced the peripheral body temperature to 29 degrees C. Hypocalcemia, which was probably due to the massive blood transfusion, was treated with calcium gluconate and calcium chloride.

Anesthesia↗
PubMed1995

[Initial ultrafiltration to the priming solution with preserved blood for cardiopulmonary bypass in infants].

In case of open heart surgery in infants, the initial priming solutions (IPS) of the cardiopulmonary bypasses (CPB) include considerable amount of preserved blood to assure us of the proper hematocrit during the CPB. Aiming at elimination of unfavorable effects of preserved blood on hearts and vessels, the ultrafiltrations (UF) to the IPS before the beginnings of CPB had been carried out in 42 pediatric cases. The IPS amounted to 915 +/- 25 (mean +/- SE) ml. in which 581 +/- 31 ml of preserved blood were included. The 1.5-fold amount infusions over the IPS, consisted of 5% glucose, normal saline and fresh frozen plasma, were added to the IPS, and just the same amount fluid were removed out by the UF. The concentrations of potassium, NH3, lactic acid and pyruvic acid in the IPS decreased significantly after UF (p = 0.001). The potassium concentrations were compared among the blood of patients (PB), the IPS before UF (IPS1), the IPS after UF (IPS2), and the mixed blood drawn 5-10 minutes after the beginnings of CPB (MB) in the cases under the age of 1 year (group-I, n = 26, 4.7 +/- 0.3 kg) and in the elders (group-E, n = 16, 15 +/- 2 kg). The results showed all significant differences but "IPS2 and MB" in group-I, and but "PB and MB" in group-E (ANOVA p = 0.001, p < 0.01 by Newman-Keuls). The 98% of cases kept their innate heart beatings until the aortic clamps at 22 +/- 1 degrees C (sending blood temp.).(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Transfusion, Autologous↗
PubMed1994

Evidence for the ligand-induced conversion from a dimer to a tetramer of the granulocyte colony-stimulating factor receptor.

An extracellular portion of granulocyte colony-stimulating factor (G-CSF) receptor, which contains an immunoglobulin-like (Ig) domain and cytokine receptor homologous (CRH) region, was secreted into the medium using Trichoplusia ni-Autographa californica nuclear polyhedrosis virus system. The gene product was purified to homogeneity mainly as a dimer (85 kDa) using G-CSF affinity column chromatography and gel filtration HPLC, although the product existed as a monomer (45 kDa) in the medium. Scatchard analyses suggested that only the dimer had high affinity ligand binding (Kd = about 100 pM), which is comparable with the Kd value of the cell surface receptor. The binding of G-CSF to Ig-CRH induced its tetramerization (200-250 kDa). The molecular composition of the tetrameric complex showed a stoichiometry of four ligands bound to four Ig-CRH. These results suggested that the oligomeric mechanism of the G-CSF receptor differs from that reported for growth hormone (GH) receptor, although CD spectrum spectroscopy suggested that the Ig-CRH has a GH receptor-like structure.

Animals↗
PubMed1994

Ligand binding domain of granulocyte colony-stimulating factor receptor.

The amino-terminal domain of the cytokine receptor homologous region (BN domain; roughly 100 amino acid residues) in the receptor for murine granulocyte colony-stimulating factor (G-CSF) was secreted as a maltose-binding protein fusion into the Escherichia coli periplasm. The murine BN domain (mBN) was prepared from the fusion protein by restriction protease Factor Xa digestion and purified to homogeneity. The purified BN domain specifically and stoichiometrically bound G-CSF, with an apparent dissociation constant (Kd) of 3-8 x 10(-8) M. The CD spectrum of the mBN domain was similar to that of the extracellular region of the human growth hormone (GH) receptor, which is composed of turns and beta-sheets held together by disulfide bonds. Tertiary folding and the beta-sheet of this small domain was confirmed by NMR spectroscopy. Disulfide bonds determined by peptide mapping were in the following locations: Cys107-Cys118, Cys153-Cys162, and Cys143-Cys194. Among them, the first and the second produce small loops (roughly 10 amino acid residues) as found in the human GH receptor. These results suggested that the mBN domain of the G-CSF receptor expressed by E. coli has a GH receptor-like structure. However, the third disulfide bond varied considerably between the G-CSF and GH receptors. Disruption of these disulfide bonds in the BN domain of the G-CSF receptor suggested that all of them are critical for maintaining a stably folded protein. Our results will facilitate understanding of the biophysical and structural properties of this receptor.

Amino Acid Sequence↗
PubMed1994

The enhancement of the extracellular carboxyl-terminal domain of human growth hormone receptor on growth hormone dependent responses of 3T3-F442A cells.

We have expressed the carboxyl-terminal domain (C domain) of the cytokine receptor homologous (CRH) region of human growth hormone receptor (hGHR) as a protein fused with maltose binding protein (MBP) in E. coli. Following proteolytic cleavage by restriction protease factor Xa, the C domain was purified to homogeneity as a monomeric form. The purified C domain appears to be folded properly judged by NMR spectrum and the far-UV circular dichroism (CD) spectrum. The C domain did not exhibit ligand binding activity. However, the C domain enhanced the human growth hormone (hGH) dependent differentiation of preadipose 3T3-F442A cells into adipose cells and the phosphorylation of a 34 kDa membrane protein.

Adipocytes↗
PubMed1994

Early retinal involvement in mitochondrial myopathy with mitochondrial DNA deletion.

BACKGROUND: Mitochondrial DNA (mtDNA) deletions have been reported in types of mitochondrial myopathy, including Kearns-Sayre syndrome (KSS). We examined mtDNA, skeletal muscle findings, and retinal electrophysiologic function in a patient believed to have incomplete KSS with ptosis and characteristic (so called salt and pepper) retinopathy, but without limitation of ocular motility and without other involvement of the central or peripheral nervous system. METHODS: Muscle biopsy specimens were examined by Gomori trichrome stain and electron microscopy. DNA extracted from muscle was examined by Southern blot analysis. Deleted mtDNA was sequenced by direct sequencing with polymerase chain reaction (PCR). Electroretinograms (ERG) and electrooculograms (EOG) were performed for electrophysiologic examination of the retina. RESULTS: There were no ragged red fibers in skeletal muscle specimens, although abnormal aggregation of mitochondria was observed on electron microscopic examination. An mtDNA deletion was detected. It spanned 5266-bp between the tRNASer gene and the ND5 gene. Electroretinographic and electrooculographic findings were normal, although extensive involvement of retinal pigment epithelium was observed on ophthalmoscopic examination. CONCLUSION: Detecting mtDNA deletion is more critical in diagnosing an incomplete phenotype of mitochondrial myopathy than is morphologic examination. We found that ophthalmoscopic fundus abnormalities preceded abnormalities on ERG and EOG.

Base Sequence↗
PubMed1994

Transgenic mice carrying the human poliovirus receptor: new animal models for study of poliovirus neurovirulence.

Recombinant viruses between the virulent Mahoney and attenuated Sabin 1 strains of poliovirus type 1 were subjected to neurovirulence tests using a transgenic (Tg) mouse line, ICR-PVRTg1, that carried the human poliovirus receptor gene. The Tg mice were inoculated intracerebrally with these recombinant viruses and observed for clinical signs, histopathological lesions, and viral antigens as parameters of neurovirulence of the viruses. These parameters observed in the Tg mice were different for different inoculated viruses. Dose-dependent incidences of paralysis and of death were observed in the Tg mice inoculated with any viruses used. This indicates that values of 50% lethal dose are useful to score a wide range of neurovirulence of poliovirus. The neurovirulence of individual viruses estimated by the Tg mouse model had a strong correlation with those estimated by monkey model. Consequently, the mouse tests identified the neurovirulence determinants on the genome of poliovirus that had been identified by monkey tests. In addition, the mouse tests revealed new neurovirulence determinants, that is, different nucleotides between the two strains at positions 189 and 21 and/or 935 in the 5'-proximal 1,122 nucleotides. The Tg mice used in this study may be suitable for replacing monkeys for investigating poliovirus neurovirulence.

Animals↗
PubMed1994

Preparation of monoclonal antibodies for immunoblotting human growth hormone receptor and growth hormone-binding protein.

Monoclonal anti-peptide antibodies against the extracellular domain of human growth hormone receptor (hGHR) were prepared. Four monoclonal antibodies (mAbs) reacted with an extracellular domain protein produced by genetic engineering. Among them, GHRP2-88 was the most reactive against hGHRs from human IM-9 cells. The lower limit of detection for immunoblotting using this mAb was about 200 pg hGHR. The GHRP2-88 antibody also reacted with deglycosylated hGHRs from tunicamycin-treated IM-9 cells and with the growth hormone-binding protein (GH-BP) in human plasma.

Antibodies, Monoclonal↗
PubMed1994

Relationship between Helicobacter pylori and atrophic gastritis.

OBJECTIVES: To investigate the relationship between Helicobacter pylori and atrophic gastritis. DESIGN AND METHODS: The extent of atrophic gastritis was assessed endoscopically in 97 non-ulcer patients, and their H. pylori status was assessed by enzyme-linked immunosorbent assay. RESULTS: The prevalence of H. pylori infection was greatest in the early stages of atrophic gastritis. Small numbers of H. pylori-negative patients were identified at different stages during the extension of atrophic gastritis. CONCLUSIONS: H. pylori infection precedes the extension of atrophic gastritis, and a minority of patients with atrophic gastritis may never have been infected with H. pylori.

Adolescent↗
PubMed1993

The development of an enzyme immunoassay for placental tissue protein 17 (PP17) and its clinical significance.

We developed an enzyme immunoassay (EIA) for placental protein 17 (PP17) using avidin biotin binding, and measured the serum-PP17 levels of 37 healthy men, 103 nonpregnant women, 48 pregnant women, and 86 patients with gynecologic malignancies. The mean level was 12.8 ng/ml in healthy men and 44.2 ng/ml in nonpregnant women (p < 0.05). The calculated upper limit of normal was 97.8 ng/ml (mean + 2 sigma). The serum PP17 concentration was remarkedly reduced postmenopausally. Pregnant women showed a mean serum level of 19.2 ng/ml, which was significantly lower than that of nonpregnant women. Immunoserological results strongly suggest that PP17 is produced far more in the normal endometrium than in the placentae and decidua. Patients with gynecologic malignancies had obviously lower mean serum PP17 levels (8.3-19.9 ng/ml) than those found in healthy nonpregnant women. Measurement of the serum PP17 concentration might be useful in distinguishing gynecologic malignancies from various normal conditions.

Biomarkers, Tumor↗
PubMed1993

Immunohistochemical and immunoelectron microscopic study of cytochrome P-450 of human fetal livers (P-450HFLa): implications for an onco-feto-placental enzyme.

Cytochrome P-450 of human fetal livers (P-450HFLa) was demonstrated by the avidin-biotin immunoperoxidase technique in tissue samples as follows: human fetal organs, adult livers, human and cynomolgus placenta, and gynecologic organs which were obtained from 40 patients with gynecologic malignancies and 32 patients with benign diseases. P-450HFLa was clearly localized in the cytoplasm and membranes of the hepatocytes, and the fact was confirmed by an immunoelectron microscopic examination. In addition, a semiquantitative assay of staining intensity demonstrated that this enzyme tended to decrease with advancing age. These findings suggest that hepatic P-450HFLa synthesis is inversely proportional to age, and that this enzyme is one of the differentiation antigens. P-450HFLa was also detected immunohistochemically in other fetal organs. The present study thus confirms that P-450HFLa is not specific to the liver and is ubiquitous even in the fetus. Marked positive staining for P-450HFLa was demonstrated in villous syncytiotrophoblasts. In contrast, no positive staining was found in the cynomolgus-monkey placenta, unlike the case for many other placental antigens. These findings lead to the tentative conclusion that P-450HFLa is a feto-placental enzyme peculiar to humans. P-450HFLa was demonstrated to occur very frequently in gynecologic malignancies. The mean positivity rate for all gynecologic malignancies was 85%, while the rate was below 25% for benign gynecologic diseases, indicating that P-450HFLa is one of the onco-feto-placental enzymes. The present study thus suggests that this enzyme could be a promising new tumor marker for gynecologic malignancies.

Animals↗
PubMed1993

The application of immunotargeting into cancer chemotherapy with carboplatin: in vitro and in vivo studies.

Anti-tumor effects of the following 2 cis-diammin (1, 1-cyclobutandicarboxylato) platin II (carboplatin, Bristol-Myers-Squibb) conjugates were evaluated through both in vitro and in vivo experiments: (1) carboplatin coupled with anti-cytokeratin monoclonal antibody (MAb), TS1 via carboxymethyl dextran (carboplatin-carboxymethyl dextran-TS1), and (2) carboplatin-carboxymethyl dextran-avidin targeted to biotinylated TS1. Using 1-ethyl-3(3-dimethylaminopropyl)-carbodiimide and N-hydroxysuccinimide, carboplatin was conjugated to carboxymethyl dextran, TS1, or avidin, at high molar ratios. The staining positivity of carboplatin-carboxymethyl dextran-TS1 in indirect immunofluorescence was almost identical to that of the original MAb. The average dose of carboplatin given in each treatment was about 60% of a clinical dose. Regarding cytotoxicity, the free drug showed the strongest effect and the best dose-dependency in cell lines: HeLa and ZR-75-1. An in vivo study giving carboplatin-MAb conjugates or free drug to HeLa tumor bearing nude rats proved that the efficacy of carboplatin-carboxymethyl dextran-TS1 in HeLa tumor was not greater than that of the free carboplatin.

Animals↗
PubMed1993

Immunoradiometrical measurement of tissue polypeptide specific antigen (TPS) in normal, healthy, nonpregnant and pregnant Japanese women.

Using a monoclonal immunoradiometrical assay, we measured the concentrations of the specific epitope M3 of tissue polypeptide antigen (TPA), namely, tissue polypeptide specific antigen (TPS), in serum and amniotic fluid obtained from normal, healthy, nonpregnant and pregnant Japanese women (NHNJW and NHPJW). The cut-off value of the serum TPS level was set at 130 U/l, based on the mean +2 standard deviations in the NHNJW. The serial measurement of serum TPS levels demonstrated the significant temporal elevation of TPS level near the time of ovulation (+/- 3 days) in the ovulatory women. In the NHPJW, the mean serum TPS level and the positivity rate (> 130 U/l) increased with the advance of gestation, reaching 183.7 U/l and 66.7%, respectively, in the third trimester. Maternal serum levels were much elevated just before (mean: 982.3 U/l) and after (mean: 824.6 U/l) delivery, and were reduced to about one-fourth by 3 days. In addition, markedly high TPS concentrations were found in the retroplacental blood (one case: 9,076 U/l) and the amniotic fluid (mean: 11,650 U/l). The serum TPS level correlated well (r = 0.871) with the serum TPA level in the TPS range of 2-2,000 U/l, while a poor correlation (r = 0.273) was found in the TPS range of 2-500 U/l. The present study thus obtained fundamental data on TPS in Japanese women. The fluctuation and change of serum TPS levels during the menstrual cycle and in pregnancy should be taken into consideration when we apply TPS as a tumor marker for women.

Adolescent↗
PubMed1993

[Results of surgical treatment of stage I lung cancer].

In this study, survival curves and background factors affecting prognosis of resected stage I lung cancer were reviewed. A total of 735 patients with primary lung cancer, including 288 cases (39.2%) of stage I lung cancer, were surgically treated at Kanazawa University Hospital from January 1973 through September 1989. The cumulative 5-year survival rate after operation for all cases of stage I lung cancer was 61.7%. The background factor which was most concerned with the survival rate was the T factor. The 5-year survival rates according to T factor were as follows: T1N0M0; 74.5%, T2N0M0; 53.8%. There was significant difference of survival rates between them (p < 0.05). Of these 288 cases, 128 cases with adenocarcinoma showed significant prolonged survival when compared to 120 cases with squamous cell carcinoma (p < 0.01). In female patients with stage I lung cancer the 5-year survival rate was significantly better than in male patients with stage I lung cancer (p < 0.01). When the survival rates were compared by ploidy pattern of the primary tumor, patients with diploid tumors showed significantly better survival than those with aneuploid tumors (p < 0.05). It is possible that adjuvant therapy is recommended to improve the survival rate of patients with stage I lung cancer, especially, those in the T2N0M0 classification.

Adenocarcinoma↗