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Biomedical subjects

H Sakai

Publications and source records attributed to H Sakai.

At least 703 records · Page 39Linked to original sources
PubMed1993

Cardiopulmonary bypass and cellular immunity: changes in lymphocyte subsets and natural killer cell activity.

To investigate whether cell-mediated immunity responses are suppressed or activated by the effect of cardiopulmonary bypass (CPB), we studied peripheral blood lymphocyte subsets and antibody-dependent cell-mediated cytotoxicity in 52 adult patients who had undergone open heart operations. Lymphocyte function also was studied with regard to mixed lymphocyte reaction, which indicates the amount of DNA synthesis of lymphocytes, and natural killer (NK) cytotoxicity, which represents the killing activity of NK cells on the tumor cells (K-562), in 11 patients. The total T lymphocyte (OKT3+ and OKT11+) number showed no significant change during CPB. Suppressor/cytotoxic T cell (OKT8+) and NK cell (Leu7+ and Leu11+) numbers were found to be remarkably increased. However, helper/inducer T cell (OKT4+) and B cell (Leu12+) numbers were decreased during CPB. Antibody-dependent cell-mediated cytotoxicity was elevated during CPB. All of these changes were almost returned to the preoperative levels by the seventh day after operation. Mixed lymphocyte reaction and NK cytotoxicity were also activated during CPB. The results show that heart operations in which cardiopulmonary bypass is used are associated with activation of cytotoxic cell-mediated immunity.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1993

A case of benign familial hyperphosphatasemia of intestinal origin.

We recently encountered a case of hyperphosphatasemia, in which > 90% of serum alkaline phosphatase (ALP) was of intestinal origin. The patient, a 51-year-old man, was found to have hyperphosphatasemia (2,341 U/L) during a routine medical check-up. All other laboratory tests and physical findings were normal. The agarose gel electrophoresis pattern of the patient's serum ALP was identical to that of common intestinal ALP from healthy adults, and only a single band of intestinal ALP was detected by immunoaffinity electrophoresis. In addition, 89% of total ALP was defined as intestinal ALP by an immunoprecipitation method. The molecular mass of the ALP was 154 kDa, almost identical with that of adult duodenal ALP. Analysis of the sugar chain structure showed an increased la fraction (74%) compared with adult duodenal ALP. Genealogical study revealed that two persons in the 5 members of the proband's family had hyperphosphatasemia of intestinal origin, indicating possible autosomal dominant inheritance.

Adult↗
PubMed1993

Carbohydrate antigen 19-9 and carcinoembryonic antigen-producing transitional cell carcinoma of the ureter and bladder: a case report.

We report a case of transitional cell carcinoma of the ureter and bladder that produced carbohydrate antigen 19-9 and carcinoembryonic antigen. The serum levels of these antigens were elevated in this patient and an immunohistochemical examination revealed that the carcinoma cells stained positively for both antigens.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1993

Prostate specific antigen and prostatic acid phosphatase immunoreactivity as prognostic indicators of advanced prostatic carcinoma.

To determine whether the prostate specific antigen (PSA) and prostatic acid phosphatase (PAP) immunoreactivities in prostatic carcinoma are reliable prognostic factors, the PSA and PAP immunohistochemical distribution was examined in needle biopsy specimens of 80 patients with advanced prostatic carcinoma. Our results indicated a higher cancer-specific survival rate in patients with a greater PSA or PAP immunostaining. Furthermore, a multivariate analysis of possible prognostic factors, that is patient age, clinical stage, Gleason score, serum PAP, PSA and PAP immunostaining scores, and the initial treatment, has confirmed that the difference in PAP immunoreactivity is the most important prognostic factor (p < 0.01) for advanced prostatic carcinoma, with the Gleason score (p = 0.06), clinical stage (p = 0.09) and PSA immunoreactivity (p = 0.48) being the second, third and fifth prognostic factors, respectively.

Acid Phosphatase↗
PubMed1993

Glycoconjugate histochemistry of the subcommissural organ in the domestic chicken: lectin histochemistry using the avidin-biotin-peroxidase complex (ABC) method.

The properties and distribution of the secretory substance in the ependymal cells of the subcommissural organ in the domestic chicken were examined with seven different lectins, using the avidin-biotin-peroxidase complex method. On the ventricular surface of this organ, LFA, PNA, RCA-I and WGA reacted positively. In the apical cytoplasm, Con A, LFA, RCA-I and WGA gave positive reactions. On the other hand, only Con A and WGA gave positive reactions in the basal cytoplasm. In the hypendymal vascular wall, LFA, RCA-I and WGA reacted positively. Neuraminidase digestion completely inhibited reactions with LFA and reduced the WGA reaction within the apical cytoplasm. At the same time, this digestion disclosed a moderately positive reaction with PNA in the apical cytoplasm. The significant findings of this study may be summarized as follows: 1) the ependymal cells of the subcommissural organ in the domestic chicken synthesize a complex oligosaccharide for a secretory product which is discharged into the ventricular cavity; 2) in the basal cytoplasm and basal processes, only oligosaccharides containing large amount of mannose are present.

Animals↗
PubMed1993

Histological examination of chick embryos with ocular hypoplasia.

From so-called "dead-in-pipped-eggs" provided by the Poultry Breeding Center of Gifu Prefecture, we obtained two chick embryos with hypoplastic eyes on external examination, and studied the visual system and cranial nerve nuclei innervating the extraocular muscles. The upper bills of both embryos deviated toward one side when observed with the naked eye. In histological sections from the most severely affected eyeball of each case primordial retinal tissue in the poorly developed orbit seemed to be at the stage of optic vesicle formation; it had not differentiated into individual layers. The optic nerve was absent from these eyeballs and the neural retina had multiple folds. The ciliary ganglion was smaller on the more severely affected side than on the contralateral side which had only mild hypoplasia. The optic nerve, which was present on the contralateral side, bifurcated at the level of the chiasma close to the diencephalic base; one branch ran toward the ipsilateral optic tectum and the other toward the contralateral brain region. The oculomotor and trochlear nerve nuclei could be identified bilaterally in one of the embryonic brains but not in the other. These findings suggest that hypoplasia of the neural retina and optic nerve in an orbit leads to bifurcation of the contralateral optic nerve which, under normal conditions, should completely cross at the chiasma. This may also suggest that retinal afferents from the brain are also affected in the hypoplastic eyeball.

Animals↗
PubMed1993

Hepatitis C virus infection in alcoholic liver cirrhosis in Japan: its contribution to the development of hepatocellular carcinoma.

To determine risk factors for hepatocellular carcinoma (HCC) in Japan, we studied 575 patients with liver cirrhosis (LC) who presented to our out-patient clinics in a month; 217 patients with habitual drinking with or without viral infections (AL-LC), 235 with hepatitis C virus (HCV) infection, 40 with hepatitis B virus (HB) infection, and 82 with liver diseases from other aetiologies such as primary biliary cirrhosis (PBC). HCC was found in 28% of AL-LC, 27% of HCV-LC, and 18% of HB-LC. HCV antibody examined by the second-generation HCV antibody assay (HCV II) was positive in 49% of AL-LC without HCC, and 84% of AL-LC with HCC. HCV was significantly associated with the development of HCC with an odds ratio of 1.90 by multivariate analysis, whereas alcohol alone did not become a risk factor, with an odds ratio of 0.65. When both variables were combined (HCV+AL), however, the odds ratio was increased twice to 3.65. One-hundred and thirteen patients who had a history of blood transfusion more than 10 years ago were selected to assess the interaction between alcohol and HCV in hepatocarcinogenesis. A year-adjusted disease occurrence rate calculated by the Kaplan-Meyer method showed that HCV+AL had a significantly higher disease occurrence rate than HCV alone. These results suggest that although alcohol alone may not become a risk factor for HCC, it may potentiate the development of HCC caused by HCV. HCV+AL is considered to be the highest risk group; strict abstinence is necessary for these patients.

Adult↗
PubMed1993

Structural study of the N-linked oligosaccharides of hepatocyte growth factor by two-dimensional sugar mapping.

The structures of the N-linked oligosaccharides on recombinant human hepatocyte growth factor (rh-HGF) expressed by Chinese hamster ovary (CHO) cells were studied by two-dimensional sugar mapping. The oligosaccharides released from the glycopeptides by peptide: N-glycosidase F (PNGase F) treatment were tagged with 2-aminopyridine at the reducing ends. The alpha-chain was linked by biantennary, triantennary, and tetraantennary oligosaccharides, but the dominant oligosaccharides linking the beta-chain were biantennary (> 85%). There was no significant difference in oligosaccharide structures between the two glycosylation sites on each chain, that is, Asn263 and Asn371 on the alpha-chain, and Asn535 and Asn622 on the beta-chain. The linkage of sialic acid to the non-reducing terminal galactose was identified as NeuAc alpha(2-3) by 1H-NMR spectrometry. The structures of the N-linked oligosaccharides from rat HGF were also studied. Triantennary oligosaccharides were obtained from the alpha-chain and a biantennary oligosaccharide was obtained from the beta-chain. This result indicates that the alpha-chain is also linked by higher branched oligosaccharides than the beta-chain in rat HGF.

Aminopyridines↗
PubMed1993

Development of voltage-gated currents in newt retinal neuroblasts in culture.

Neuroblasts dissociated from early regenerating newt retina (18-20 days after surgery) survived in culture and extended neurites. They were classified into three groups on the basis of neurite outgrowth patterns; monopolar, bipolar, and multipolar varieties. Freshly dissociated neuroblasts (3-15 h in culture) were characterized by slow-rising action potentials with long duration, mediated by inward Na+ currents. After a few days in culture, these cells produced much briefer action potentials mediated by the characteristic Na+, Ca2+ and K+ currents of ganglion cells dissociated from normal retina. The results suggest that neuroblasts in early regenerating retina differentiate in vitro into spiking cells, possibly ganglion cells, characterized by their morphology and voltage-dependent ionic currents.

Action Potentials↗
PubMed1993

Reactive lymphoid hyperplasia of the liver.

A patient with reactive lymphoid hyperplasia of the liver was symptom free and had no underlying disease except for diabetes mellitus. The hepatic tumor was found by ultrasound examination at routine checkup. The preoperative diagnosis of the tumor was unsuccessful despite various radiological examinations. Histological examination of the resected tumor showed that it was composed of benign-appearing lymphocytic proliferations forming lymphoid follicles that included numerous germinal centers. The germinal center was mainly composed of B-cell marker, L26-positive lymphocytes, but a few T cells were also found. Lymphocytes surrounding germinal centers were mainly T-cell marker, UCHL1-positive T-cells, and a small number of B cells. The B cells in the lymphoid follicles were stained for both kappa and lambda light chains at equal frequency, indicating polyclonal and benign nature. A diagnosis of reactive lymphoid hyperplasia of the liver seems justified.

B-Lymphocytes↗
PubMed1993

Increased plasma endothelin-1 levels in patients with cirrhosis and esophageal varices.

We measured plasma levels of endothelin-1, a potent vasoconstrictor peptide, in 6 healthy controls and 20 patients with cirrhosis and correlated them with various clinical and laboratory parameters and other vasoactive substances. There was a trend toward increased endothelin-1 levels in patients with cirrhosis compared with controls (6.0 +/- 2.5 vs. 4.4 +/- 1.5 pg/ml, NS). The presence of ascites did not influence plasma endothelin-1 levels, and plasma endothelin-1 levels were not significantly correlated with serum albumin, serum bilirubin, or prothrombin time. Plasma endothelin-1 levels were significantly elevated in cirrhotic patients with esophageal varices compared with those without varices (7.5 +/- 2.5 vs. 4.5 +/- 1.6, p < 0.05). The elevation of endothelin-1 levels in patients with varices may represent a physiological compensation for the systemic vasodilation present in patients with liver cirrhosis and portal hypertension.

Endothelins↗
PubMed1993

Purification and immunohistochemical localization of aspartic proteinases in rat epidermis.

Investigation of skin cathepsin E (EC 3.4.23.-) has been totally ignored compared to skin cathepsin D (ED 3.4.23.5). In this study both cathepsins E and D were simultaneously purified to homogeneity up to 370 and 640 times, respectively, from 2-day-old rat epidermis. The total aspartic proteinase activity of rat epidermis detected after Q-Sepharose column chromatography was attributed to 27% cathepsin E, 63% cathepsin D, and 10% other enzymes. The purified enzymes showed that cathepsin E (90 kDa) is a dimer of 45 kDa subunits whereas cathepsin D is a monomer of 42 kDa. Other biochemical properties of epidermal cathepsins E and D were similar to those reported from other tissue sources. Immunologically cathepsins E and D were distinct from each other and localization of the two enzymes differed in both rat and human skin by immunohistochemistry. Cathepsin E was distributed diffusely in the cytoplasm of almost all epidermal cells, though its concentration increased above suprabasal cells, whereas cathepsin D appeared in particulate form only in cells of the granular layer. The findings indicate that two aspartic proteinases that have similar enzymatic properties exist in the epidermis. They are, however, differentially distributed in the organ, presumably for different functions during the process of keratinization.

Animals↗
PubMed1993

Small-conductance Cl- channels in rabbit parietal cells activated by prostaglandin E2 and inhibited by GTP gamma S.

1. Small-conductance, sub-picosiemens (sub-pS) Cl- channels in the basolateral membrane of non-stimulated parietal cells in isolated rabbit gastric glands were studied by whole-cell patch-clamp and noise analysis techniques. 2. Voltage-independent whole-cell Cl- currents were recorded from parietal cells equilibrated with Cl(-)-containing solutions. Intracellular application of guanosine-5'-O-(3-thiotriphosphate) (GTP gamma S, 5-200 microM) slowly decreased the whole-cell Cl- current, and its steady-state effect was observed about 6 min after the start of the dialysis. The half-maximal inhibitory concentration of GTP gamma S was about 60 microM. 3. The single Cl- channel conductance was estimated to be 0.37 pS from the variance noise analysis during the GTP gamma S-induced inhibitory process of the whole-cell Cl- current. It is in agreement with the value obtained by a method of power spectrum analysis (0.47 pS). 4. The whole-cell Cl- current was increased by prostaglandin E2 (10 microM). The increased Cl- current was reduced by the subsequent application of GTP gamma S (50 microM), whereas the GTP gamma S (50 microM)-induced inhibition of the Cl- current was not reversed by the subsequent application of prostaglandin E2 (10 microM). 5. The combined intracellular application of GTP gamma S (50 microM) and GDP beta S (500 microM) markedly reduced the inhibitory effect of GTP gamma S, indicating that a GTP-binding protein is involved in the regulation of the Cl- channel. 6. Treatment of parietal cells with pertussis toxin (PTX, 500 ng/ml) for 90-140 min did not affect the GTP gamma S-induced inhibition of the whole-cell Cl- current. 7. Intracellular application of cyclic AMP-dependent protein kinase inhibitor peptide (100 micrograms/ml) or 1,2-bis(O-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA) (5 mM, pCa 8) did not affect the GTP gamma S-induced inhibition of the whole-cell Cl- current. 8. The present study has suggested that the opening of the sub-pS Cl- channel is modulated negatively by a PTX-insensitive GTP-binding protein and positively by prostaglandin E2.

Animals↗
PubMed1993

Transcriptional regulation of Bacillus thuringiensis subsp. israelensis mosquito larvicidal crystal protein gene cryIVA.

The cryIVA gene encodes a component of the delta-endotoxin of Bacillus thuringiensis subsp. israelensis. By S1 nuclease mapping and primer extension analysis, we have identified the transcriptional initiation site of cryIVA. The transcriptional activity from the promoter was detected only for the sporulating cells more than 3 h after onset of the stationary phase. Upstream from the cryIVA transcriptional initiation site was found a nucleotide sequence partially homologous to the promoter consensus sequence for the E sigma E holoenzyme of Bacillus subtilis. Thus, it was strongly suggested that the identified cryIVA promoter, like some other crystal protein gene promoters, was under the control of sigma 35, the B. thuringiensis homolog of sigma E.

Amino Acid Sequence↗
PubMed1993

Integration is essential for efficient gene expression of human immunodeficiency virus type 1.

A mutant of human immunodeficiency virus type 1 which carries a frameshift insertion in the integrase/endonuclease region of pol gene was constructed in vitro. Upon transfection into cells, although this mutant exhibited a normal phenotype with respect to expression of gag, pol, and env genes and to generation of progeny virions, no replication-competent virus in CD4-positive cells emerged. An assay for the single-step replication of a defective viral genome dependent on trans complementation by rev protein was established and used to monitor the early phase of viral infection process. Viral clones with a mutation in the vif, vpr, or vpu gene displayed no abnormality in the early phase. In contrast, the integrase mutant did not direct a marker gene expression after infection. Together with an observation that the mutant lacked the ability to integrate, these results indicated that the integration was required for efficient viral gene expression and productive infection of human immunodeficiency virus type 1.

Cell Line↗