Biomedical subjects

Y Hirai

Publications and source records attributed to Y Hirai.

At least 145 records · Page 8Linked to original sources

PubMed1996

A new strategy for large-scale preparation of high-titer recombinant adeno-associated virus vectors by using packaging cell lines and sulfonated cellulose column chromatography.

The extensive testing of adeno-associated virus (AAV) as a vector for human gene therapy has been hampered by low efficiency of the current packaging system, which is based on transient transfection with plasmid DNAs and infection with adenovirus in permissive cells. In an effort to resolve this problem, HeLa cell-based packaging cell lines were established. These packaging cells carry multiple copies of the AAV genome lacking the inverted terminal repeat (ITR) sequences. The AAV genes were silent in these cells but inducibly expressed by adenovirus infection. When the AAV vector plasmid containing the neoR gene flanked by the ITRs was also integrated into these cells, efficient production of the recombinant AAV particles occurred after adenovirus infection. AAV vector particles in cell lysates could be concentrated by sulfonated cellulose column chromatography. Using the packaging cells and the column chromatography technique, it is possible to prepare AAV vectors with the titer of higher than 10(8) cfu/ml or 5 x 10(10) particles/ml. This new strategy should be useful for testing AAV vectors in vivo.

Cellulose↗

PubMed1996

Inductive influences of epimorphin on endothelial cells in vitro.

Epimorphin is known as a mesenchymal factor involved in epithelial morphogenesis. This protein has, however, a curious nature in that only certain of its molecules are transported to extracellular regions after having undergone complex conformational changes. In the present study, we generated an N-terminally modified recombinant epimorphin fragment as a substitute for the extracellular epimorphin and examined n detail how this polypeptide affects cellular behavior in a model cell system. As immunohistochemical studies revealed that epimorphin is abundant in regions close to endothelial cells in venulae, we chose endothelial cells as the model cell and investigated the influence of this polypeptide on their cellular behavior in vitro. The recombinant epimorphin guided the endothelial cells to align themselves in tandem and to present a branched morphology in the three-dimensional culture system. We also discovered that the endothelial cells were induced to secrete several cytokines, including those involved in angiogenesis, and were suppressed in terms of proliferation by this molecule. These results suggest that epimorphin has a regulatory role in the activation of endothelial cells and is active in supporting the resulting cellular arrangement.

Animals↗

PubMed1996

Quantitative detection of secretory immunoglobulin A to Helicobacter pylori in gastric juice: antibody capture enzyme-linked immunosorbent assay.

Helicobacter pylori is a major etiologic agent in gastroduodenal disorders. In this study, immunoglobulin A (IgA) antibodies to H. pylori were estimated in serum and gastric juice specimens from patients with gastritis and peptic ulcers using antibody capture enzyme-linked immunosorbent assays (ACELISAs). The antibody titers of the ACELISAs are independent of the antibody concentration and reflect the ratio of H. pylori-specific IgA to total IgA. The ratio is stable, although the antibody concentration fluctuates in gastric juice. Using the ACELISAs it was possible to evaluate quantitatively not only serum IgA (SR-IgA) antibodies but also secretory IgA (SC-IgA) antibodies in gastric juice. There were significant differences between the patients and control group in the SR-IgA and SC-IgA ACELISAs. Furthermore, the ACELISAs made it possible to compare between SR-IgA antibodies in serum and SC-IgA antibodies in gastric juice. In all patients, the ratios of H. pylori-specific IgA were higher in gastric juice than in serum. These results suggest that H. pylori SC-IgA antibodies are mainly produced by the local immune response in the gastric mucosa. Our studies indicate that ACELISA is well suited for the analysis of local immune response in mucosa.

Adult↗

PubMed1996

Ovarian hemangioma associated with concomitant stromal luteinization and ascites.

A 62-year-old female presented with a pelvic mass and ascites. The Papanicolaou vaginal smear showed an unusual maturation, maturation index being 0/80/20. The serum level of estradiol was 48.7 pg/ml. The preoperative checkup suggested a pelvic malignancy with a differential diagnosis of hormone-secreting ovarian tumor. On surgical exploration, she had a hemangioma of the ovary without malignant cytology in the ascitic fluid. Histologically, this tumor was associated with stromal luteinization. This is the first case, reported in the literature, possessing ovarian hemangioma with stromal luteinization accompanying massive ascites. It should be noted that an ovarian hemangioma can be associated with stromal luteinization and ascites, and that MR imaging is sometimes of value for making a preoperative diagnosis of ovarian hemangioma.

Ascites↗

PubMed1996

Pelvic lymph node metastasis in endometrial cancer with no myometrial invasion.

OBJECTIVE: To analyze the incidence of pelvic lymph node metastasis in endometrial carcinoma with no myometrial invasion. METHODS: Between 1971 and 1995, 684 women with stage I endometrial carcinoma underwent total abdominal hysterectomy, bilateral salpingo-oophorectomy, and pelvic lymph-adenectomy. The incidence of pelvic lymph node metastases in 100 cases without myometrial invasion was examined. RESULTS: Histologic examination of the surgical specimens revealed a single pelvic lymph node metastasis in each of four cases. The incidence of pelvic lymph node metastasis was four of 83 in grade 1, zero of 13 in grade 2, and zero of four in grade 3 tumors. CONCLUSION: Pelvic lymph node metastasis in endometrial cancer with no myometrial invasion is not rare, even with grade 1 tumors. Lymphadenectomies may be necessary in all patients with endometrial cancer, except when clinical or operative factors increase the procedure's risk of morbidity.

Adenocarcinoma↗

PubMed1996

Steroidal glycosides from the subterranean parts of Liriope spicata var. prolifera.

In a continuation of phytochemical studies on the underground organs of Liriope spicata var. prolifera, four new steroidal glycosides, lirioproliosides A-D, along with two known compounds, 25(S)-ruscogenin 1-O-[alpha-L-rhamnopyranosyl(1-->2)[beta-D-xylopyranosyl (1-->3)]-beta-D-fucopyranoside and ophiopogonin A, were identified. The structures of lirioproliosides A-D were established by a combination of spectroscopic and chemical methods as 25(S)-ruscogenin 1-O-[alpha-L-rhamnopyranosyl(1-->2)][beta-D-xylopyranosyl (1-->3)]-beta-D-fucopyranoside-3-O-alpha-L-rhamnopyranoside, 25(S)-ruscogenin 1-O-[3-O-acetyl-alpha-L-rhamnopyranosyl(1-->2)]-beta-D-fucopyranoside, 25(S)-ruscogenin (1-O-[2-O-acetyl-alpha-L-rhamnopyranosyl (1-->2)]-beta-D-fucopyranoside and ruscogenin (1-O-[2-O-acetyl-alpha-L-rhamnopyranosyl(1-->2)]-beta-D-fucopyranoside, respectively. Among these steroidal glycosides, ophiopogonin A and lirioprolioside B, and lirioproliosides C and D, were isolated as epimeric pairs.

Glycosides↗

PubMed1996

Human astrocytoma cells (U-87 MG) exhibit a specific substance P binding site with the characteristics of an NK-1 receptor.

To investigate substance P (SP) receptors on an established human astrocytoma cell line (U-87 MG), [3H][Sar9,Met(O2)11]-SP, a selective SP receptor agonist, was used to identify and characterize the cell membrane binding sites for SP. SP receptor mRNA was examined by solution hybridization analysis, and the existence of SP binding protein on the surface of membranes was evaluated by flow cytometry using an anti-SP binding protein antibody. In U-87 MG and U-373 MG RNA preparations, transcripts were identified that corresponded to both mature and partially spliced receptor forms. In U-87 MG cell membrane-enriched preparations, the binding of [3H][Sar9,Met(O2)11]-SP was found to be time and cell number dependent, specific, saturable, and of high affinity. Equilibrium binding analysis revealed a single class of binding sites with an apparent KD of 1.15 +/- 0.15 nM and a Bmax of 108 +/- 9.8 fmol/mg of protein. [3H][Sar9, Met(O2)11]-SP binding was basically not influenced by addition of mono (Na+, Li+) or divalent (Mg2+, Mn2+, Ca2+) cations; only high doses of divalent cations decreased the binding. GTP and guanylyl-5'-imidodiphosphate, but not GDP and GMP, reduced the Bmax without changing the affinity of [3H][Sar9,Met(O2)11]-SP. We also examined the effects of pretreatment with three lectins [concanavalin A (con A), wheat germ agglutinin (WGA), and Lens culinaris agglutinin (LCA)] to determine the nature of carbohydrate chains on the U-87 MG cell. Of three lectins analyzed for effects on agonist binding, WGA and LCA had an inhibitory effect, whereas con A was ineffective. These results suggest that SP receptors on the human astrocytoma cell line U-87 MG have either a biantennary complex-type or a high mannose-type of carbohydrate chain and may be regulated by GTP-binding protein(s).

Astrocytoma↗

PubMed1996

Effects of moderate-intensity endurance and high-intensity intermittent training on anaerobic capacity and VO2max.

This study consists of two training experiments using a mechanically braked cycle ergometer. First, the effect of 6 wk of moderate-intensity endurance training (intensity: 70% of maximal oxygen uptake (VO2max), 60 min.d-1, 5 d.wk-1) on the anaerobic capacity (the maximal accumulated oxygen deficit) and VO2max was evaluated. After the training, the anaerobic capacity did not increase significantly (P > 0.10), while VO2max increased from 53 +/- 5 ml.kg-1 min-1 to 58 +/- 3 ml.kg-1.min-1 (P < 0.01) (mean +/- SD). Second, to quantify the effect of high-intensity intermittent training on energy release, seven subjects performed an intermittent training exercise 5 d.wk-1 for 6 wk. The exhaustive intermittent training consisted of seven to eight sets of 20-s exercise at an intensity of about 170% of VO2max with a 10-s rest between each bout. After the training period, VO2max increased by 7 ml.kg-1.min-1, while the anaerobic capacity increased by 28%. In conclusion, this study showed that moderate-intensity aerobic training that improves the maximal aerobic power does not change anaerobic capacity and that adequate high-intensity intermittent training may improve both anaerobic and aerobic energy supplying systems significantly, probably through imposing intensive stimuli on both systems.

Adult↗

PubMed1996

[Peripheral lymphocyte subset of patients with pancreatic diabetes mellitus--about a decreased ratio of T-LGL and ability of host defense].

Patients with diabetes mellitus (DM) often suffer from various and severe infection. Patients with pancreatic DM have malnutrition due to chronic pancreatitis. Therefore it is believed that patients with pancreatic DM have a lower ability of host defence to infectious diseases than normal subjects. We examined the primpheral lymphocyte subsets (T cell, B cell, NK cell, CD3+ 56+ T) of eighteen patients (males, age = 52.8 +/- 12.7 years old, mean +/- SD) with pancreatic DM by two color flow-cytometry to evaluate the lymphocyte function. Ratios of T cell (T%, 66.9 +/- 9.3%, mean +/- SD). B cell (B%, 13.1 +/- 5.8%) and NK cell (Nk%, 19.3 +/- 8.7%) to total peripheral lymphocytes of patients with pancreatic DM were not significantly different from those (T% = 66.4 +/- 7.8%, B% = 13.5 +/- 6.7%, NK% = 19.9 +/- 9.1%) of thirteen normal subjects (males, age = 51.2 +/- 13.1). CD3+56+ T cell % (4.1 +/- 1.9%) of patients with pancreatic DM was lower than that (6.0 +/- 3.0%) of normal subjects (p < 0.05). CD3+56+ T cells have cytotoxic activity and it is likely that this activity is similar to that of NK cells. These results suggested that a decrease in peripheral CD3+56+ T cell % is a factor showing a weak host defense mechanism to infectious diseases in patients with pancreatic DM.

Adult↗

PubMed1996

Lipid profile of Helicobacter spp.: presence of cholesteryl glucoside as a characteristic feature.

The lipid and fatty acid profiles of eight Helicobacter spp. (H. nemestrinae, H. acinonyx, H. canis, Helicobacter sp. strain CLO-3, "H. rappini" [Flexispira rappini], H. pametensis, Helicobacter sp. strain Bird-B, and Helicobacter sp. strain Bird-C) and the fatty acid profiles of five additional species (H. pylori, H. felis, H. muridarum, H. mustelae, and H. fennelliae) were analyzed and compared. A heterologous fatty acid profile was observed among the Helicobacter spp., and on that basis the species could be divided into two groups. Group A had 19-carbon cyclopropane fatty acid (19:0cyc) and tetradecanoic acid (14:0) as the major fatty acids, and group B characteristically lacked the 19:0cyc and had hexadecanoic acid (16:0) and octadecenoic (18:1) acids as the major fatty acids. The species of group A are primarily gastric colonizers, and those of group B are primarily intestinal colonizers. Seven of the eight species studied showed the unusual and characteristic presence of cholesteryl glucosides (CGs), and most of these seven showed a very large amount (9.7 to 27.4% of the weight of total extractable lipid). The types of CGs and their distribution in different species were as follows: cholesteryl-6-O-acyl-alpha-D-glucopyranoside (cholesteryl-6-O-tetradecanoyl-alpha-D-glucopyranoside in H. nemestrinae and mainly cholesteryl-6-O-dodecanoyl-alpha-D-glucopyranoside in "H. rappini"), cholesteryl-alpha-D-glucopyranoside (H. nemestrinae, H. acinonyx, H. canis, Helicobacter sp. strain CLO-3, and "H. rappini"), and cholesteryl-6-O-phosphatidyl-alpha-D-glucopyranoside (H. nemestrinae, H. acinonyx, H. canis, and Helicobacter sp. strain CLO-3). Besides this, we could also detect cholesteryl acyl glucoside in H. acinonyx, cholesteryl glucoside in Helicobacter sp. strains Bird-B and -C, and cholesteryl phosphatidyl glucoside in "H. rappini" and Helicobacter sp. strain Bird-C. A selective accumulation of free cholesterol was observed in the neutral lipid fractions. On the basis of the detection of CGs in 11 of the 13 species studied so far, the presence of CGs appears to be a characteristic feature of the genus Helicobacter. In view of this and also because of a simple and rapid detection method described herein, the CGs can be used as a valuable chemotaxonomic marker.

Cholesterol↗

PubMed1996

Priming effect of platelet activating factor on leukotriene C4 from stimulated eosinophils of asthmatic patients.

BACKGROUND: Eosinophils from asthmatic patients are known to release greater amounts of leukotrienes than normal eosinophils when stimulated by the calcium ionophore A23187. The effect of platelet activating factor (PAF) in priming eosinophils was investigated. METHODS: Eosinophils were obtained from 18 asthmatic patients and 18 healthy donors. Cells separated by the Percoll gradients were incubated with PAF (C-18) for 30 minutes and then stimulated with the calcium ionophore A23187 (2.5 microM) for 15 minutes. The amount of leukotriene C4 (LTC4) in supernatants was measured using a combination of high pressure liquid chromatography and radioimmunoassay. RESULTS: The mean (SD) amount of LTC4 released by eosinophils from asthmatic patients upon stimulation with the calcium ionophore A23187 alone was 27.9 (9.9) ng/10(6) cells (n = 6). The amount of LTC4 released following stimulation with the calcium ionophore A23187 after pretreatment with PAF (1, 5, and 10 microM) was 57.2 (8.9), 75.1 (14.3), and 52.6 (10.7) ng/10(6) cells (n = 6), respectively. Trace amounts of LTC4 (0.9 (0.02) ng/10(6) cells, n = 6) were detected in the supernatant of the cells after stimulation by PAF alone (5 microM). The amount of LTC4 released upon stimulation by calcium ionophore A23187 alone in eosinophils from healthy donors was 10.3 (3.7) ng/10(6) cells (n = 4). The amounts of LTC4 released upon stimulation with calcium ionophore A23187 after pretreatment with PAF at concentrations of 1, 5, and 10 microM were 11.9 (3.5), 17.8 (5.6), and 12.7 (5.1) ng/10(6) cells (n = 4), respectively. Trace amounts of LTC4 (0.6 (0.02) ng/10(6) cells, n = 4) were detected in the supernatant of the cells upon stimulation with PAF alone (5 microM). The amounts of LTC4 released upon stimulation with calcium ionophore A23187 after pretreatment with lyso-PAF at concentrations of 1, 5, and 10 microM (n = 4 or 6) were 30.8 (5.2), 22.9 (5.1), and 27.3 (4.3) ng/10(6) cells (n = 6) from the eosinophils of asthmatic patients and 13.7 (3.3), 15.2 (4.9), and 14.7 (3.8) ng/10(6) cells (n = 4) from the eosinophils of healthy donors. CONCLUSIONS: The results indicated that PAF enhanced LTC4 formation by eosinophils obtained from asthmatic patients stimulated with the calcium ionophore A23187, but not those obtained from normal subjects.

Adult↗

PubMed1996

Cloning, expression, and mapping of CKAPI, which encodes a putative cytoskeleton-associated protein containing a CAP-GLY domain.

From a human fetal-brain cDNA library we isolated a novel cDNA clone encoding a protein containing a CAP-GLY domain that is highly conserved among several cytoskeleton-associated proteins. The CAP-GLY domain is thought to be essential for their association with microtubules. The cDNA, designated CKAPI (for cytoskeleton-associated protein I, glycine motif) contained an open reading frame of 579 nucleotides encoding 193 amino acids. Northern-blot analysis revealed expression of three transcripts, 1.0, 3.4, and 4.6 kb in size, in all tissues examined. The 1.0-kb transcript was significantly higher in brain and heart than in other tissues. This gene was mapped by FISH to chromosome bands 19q13.11-->q13.12.

Amino Acid Sequence↗

PubMed1996

Cloning, expression, and mapping of TCTEL1, a putative human homologue of murine Tcte1, to 6q.

From a human fetal-brain cDNA library we isolated a putative human homologue of the murine Tcte1 gene. The cDNA, designated TCTEL1, contained an open reading frame of 339 nucleotides encoding 113 amino acids. The predicted peptides of TCTEL1 showed 94% and 55% identity (100% and 94% similarity) with those of murine Tcte1 and human RP3. Northern-blot analysis revealed a 0.9-kb transcript in all tissues examined. This gene was mapped by FISH to chromosome bands 6q25.2 --> q25.3, the syntenic region of the murine t-complex locus of chromosome 17.

Animals↗

PubMed1996

Cloning, expression pattern and mapping to 12p 13.2 --> p13.1 of CLAPS3, a gene encoding a novel clathrin-adaptor small chain.

From a human fetal-brain cDNA library we isolated a novel gene encoding a peptide homologous to clathrin-adaptor small chains in rat, mouse, and yeast. The cDNA, designated CLAPS3 (clathrin-associated/assembly/adaptor protein, small 3, 22 kDa), contained an open reading frame of 579 nucleotides encoding 193 amino acids. Northern-blot analysis revealed expression of a 1.35-kb transcript in all human tissues examined. This gene was mapped to chromosome bands 12p13.2 --> p13.1 by FISH.

Adaptor Protein Complex 3↗

PubMed1996

Cloning, expression and chromosome mapping of adducin-like 70 (ADDL), a human cDNA highly homologous to human erythrocyte adducin.

From a human fetal-brain cDNA library we isolated a novel human cDNA, termed human adducin-like 70 (gene symbol ADDL), whose predicted amino acid sequence showed a high degree of homology to adducins. This cDNA clone (ADDL), which contained an open reading frame of 2,022 nucleotides encoding 674 amino acids, revealed 54%, 53%, and 59% identity in predicted amino acid sequence with alpha and beta components of human adducin and rat adducin 63, respectively. Human adducin-like 70 is likely to play an important role in the skeletal organization of the cell membrane. Northern blot analysis indicated ubiquitous expression of this gene in adult human tissues. We localized the gene to chromosome bands 10q24.2-->q24.3 by fluorescence in situ hybridization (FISH).

Adult↗

PubMed1996

Molecular cloning of UBE2G, encoding a human skeletal muscle-specific ubiquitin-conjugating enzyme homologous to UBC7 of C. elegans.

From a human fetal-brain cDNA library we isolated a novel ubiquitin-conjugating enzyme. The cDNA, designated UBE2G, contained an open reading frame of 510 nucleotides encoding 170 amino acids. The predicted peptide product showed 74% identity at the amino acid level with UBC7 of C. elegans, a high degree of homology with UBC7s of other species, and significant homologies with other subgroups of UBCs. Northern-blot analysis revealed strong expression of 4.4-kb, 2.4-kb, and 1.6-kb transcripts in skeletal muscle. Weak expression was observed in 15 other tissues examined. Radiation-hybrid mapping localized this cDNA to chromosome band lq42.

Animals↗

PubMed1996

Cloning, expression pattern and mapping to Xq of NAP1L3, a gene encoding a peptide homologous to human and yeast nucleosome assembly proteins.

From a human fetal brain cDNA library, we isolated a novel gene sharing significant homology with the genes of nucleosome assembly proteins (NAPs). This cDNA clone, designated NAP1L3 (nucleosome assembly protein 1-like 3), contained an open reading frame of 1518 nucleotides encoding 506 amino acids. Its predicted amino acid sequence showed 46% identity and 65% similarity with NAP1L. In its C-terminal half NAP1L3 contained several characteristic motifs strictly conserved with NAP1L and yeast NAP1, but the N-terminal half showed little conservation. Northern-blot analysis revealed strong expression of a 3.0-kb transcript in human adult brain and weak expression in heart. NAP1L3 was closely linked to a marker (DXS990) mapped to chromosome bands Xq21.3-->q22, where genes responsible for several X-linked mental retardation syndromes have been localized.

Amino Acid Sequence↗

PubMed1996

Monitoring exposure to atomic bomb radiation by somatic mutation.

Atomic bomb survivors are a population suitable for studying the relationship between somatic mutation and cancer risk because their exposure doses are relatively well known and their dose responses in terms of cancer risk have also been thoroughly studied. An analysis has been made of erythrocyte glycophorin A (GPA) gene mutations in 1,226 atomic bomb survivors in Hiroshima and Nagasaki. The GPA mutation frequency (Mf) increased slightly but significantly with age at the time of measurement and with the number of cigarettes smoked. After adjustment for the effect of smoking, the Mf was significantly higher in males than in females and higher in Hiroshima than in Nagasaki. All of these characteristics of the background GPA Mf were in accord with those of solid tumor incidence obtained from an earlier epidemiological study of A-bomb survivors. Analysis of the dose effect on Mf revealed the doubling dose to be about 1.20 Sv and the minimum dose for detection of a significant increase to be about 0.24 Sv. No significant dose effect for difference in sex, city, or age at the time of bombing was observed. Interestingly, the doubling dose for the GPA Mf approximated that for solid cancer incidence (1.59 Sv). And the minimum dose for detection was not inconsistent with the data for solid cancer incidence. The dose effect was significantly higher in those diagnosed with cancer before or after measurement than in those without a history of cancer. These findings are consistent with the hypothesis that somatic mutations are the main cause of excess cancer risk from radiation exposure.

Adult↗