Search PubMed⌕ Search

Biomedical subjects

Y Fukuda

Publications and source records attributed to Y Fukuda.

At least 559 records · Page 31Linked to original sources
PubMed1993

Induction of natural suppressor-like cells from human adult peripheral blood lymphocytes by a K562-derived factor.

K562-AC1, a subclone of the human myeloid leukemia cell line K562, secreted an inhibitor of PHA-stimulated human T cell growth into the culture supernatant (K562sup). Kinetics and absorption assays in vitro revealed that the factor acts on PBMC during the very early growth phase. PBMC gained potent suppressor activity against autologous T cell growth after preculture with K562sup for 3 days in a dose-related manner. HLA class II negative and nylon wool-nonadherent subsets possessed higher suppressor potential than unfractionated PBMC. Treatment of K562sup-precultured PBMC with mAb followed by complement-lysing showed that the responsible suppressors belong to null cells expressing CD3-, CD4-, CD19-, CD14-, CD11b-, but partially CD2+. Exogenous IL-2 exhibited a synergistic effect on the activity of the suppressors committed by K562sup. However, K562sup inhibited IL-2-activated lymphocytes from generating anti-K562 cytolytic activity. Macrophages inhibited the induction of the suppressors, which was restored by adding indomethacin and/or IL-2. In conclusion, K562sup has the ability to induce efficient suppressor cells from human adult PBL, which belong to null cells without NK/lymphocyte-activated killer activity and are similar to natural suppressor cells.

Humans↗
PubMed1993

A positive correlation between the precursor frequency of cytotoxic lymphocytes to autologous Epstein-Barr virus-transformed B cells and antibody titer level against Epstein-Barr virus-associated nuclear antigen in healthy seropositive individuals.

A limiting dilution analysis was established to determine the precursor frequency (PF) of cytotoxic lymphocytes against autologous B cells transformed with the Epstein-Barr virus (EBV). This method was found to detect mainly self-restricted T-cell activity and little non-self-restricted cytotoxicity. The mean PF in 21 healthy EBV-seropositive persons was 1.4 x 10(-3) (range: 0.03 x 10(-3) to 8.7 x 10(-3)) for peripheral blood mononuclear cells, whereas 4 samples of mononuclear cells obtained from umbilical cord blood had PFs below 0.007 x 10(-3). A positive correlation was observed between the PF and serum antibody titers against EBV-associated nuclear antigen among the seropositive persons.

Antibodies, Viral↗
PubMed1993

Haem is necessary for a continued increase in ferrochelatase mRNA in murine erythroleukaemia cells during erythroid differentiation.

The level of mRNA encoding ferrochelatase (FeC) was examined in two murine erythroleukaemia (MEL) clones, DS and DR, a DMSO-sensitive, and a DMSO-resistant clone, respectively. DS cells undergo erythroid differentiation by DMSO treatment with a marked increase in haem synthesis, while DR cells fail to do so due to the lack of the erythroid-specific delta-aminolaevulinate synthase (ALAS-E). Both DS and DR cells showed an increase in the level of FeC mRNA within 18 h of DMSO treatment. The level of FeC mRNA in DR cells was then decreased, while that in DS cells continued to increase for 72 h. Treatment with haemin significantly increased FeC mRNA in DR cells. When cells were treated with both DMSO and haemin, the level of FeC mRNA in DR cells increased to a level comparable to that in DS cells. These findings suggest that the failure to maintain increased FeC mRNA DR cells after DMSO treatment may be due to a deficiency of haem in these cells.

Animals↗
PubMed1993

Dimethyl sulphoxide and haemin induce ferrochelatase mRNA by different mechanisms in murine erythroleukaemia cells.

The level of mRNA encoding ferrochelatase (FeC), the terminal enzyme of the haem biosynthetic pathway, was examined in murine erythroleukaemia (MEL) cells when they were induced to undergo erythroid cell differentiation by treatment with dimethyl sulphoxide (DMSO), or haemin. FeC mRNA increased within 12 h after DMSO or haemin treatment of MEL cells, and its level continued to increase for 48 h. Treatment of cells with succinylacetone (SA), a potent inhibitor of haem synthesis, suppressed a DMSO-mediated increase in FeC mRNA, and haemin treatment reversed a SA-mediated decrease in FeC mRNA. Nuclear runoff analyses showed that, while DMSO increased the rate of transcription of FeC mRNA, haemin did not. These results indicate that the induction of FeC mRNA by DMSO is largely transcriptional, while that by haemin is post-transcriptional.

Animals↗
PubMed1993

Intra-abdominal desmoplastic small cell tumor in an adolescent suggesting a neurogenic origin.

A case of a desmoplastic small cell tumor of the large omentum associated with gross ascites that occurred in a male adolescent is reported. Light microscopic studies revealed that the tumor cells were small and epithelioid in nature with eosinophilic hyaline material located in the perinuclear area. They were surrounded by rich desmoplastic and myxoidal stromal bands. Immunohistochemical staining revealed globoid perinuclear positivity for desmin. Vimentin, cytokeratin (AE3, CaM 5.2), epithelial membrane antigen, tissue polypeptide antigen, neuron-specific enolase, chromogranin A, endocrine granule constituent and synaptophysin were also positive in the cytoplasm. Electron microscopy revealed whorled intermediate filaments and some dense core granules in the cytoplasm. Bundles of microtubules in the cytoplasmic process and occasional cell junctions of zonulae adherentes in the tumor cells were also observed. DNA analysis of the tumor cells showed the three-fold amplification of the N-myc gene. Although desmoplastic small cell tumors showed a heterogeneous pattern with immunohistochemical studies, it is suggested that the tumor may originate from neurogenic cells.

Adolescent↗
PubMed1993

Histogenesis of abnormal elastic fibers in blebs and bullae of patients with spontaneous pneumothorax: ultrastructural and immunohistochemical studies.

Elastic fibers in 15 blebs and 17 bullae with spontaneous pneumothorax were studied by means of electron microscopy and light and electron microscopic immunohistochemistry for elastin and alpha 1-antitrypsin. Blebs were formed in association with focal organized alveoli, and bullae were formed in association with pulmonary emphysema. Both blebs and bullae had abnormal elastic fibers. Ultrastructurally, abnormal elastic fibers of blebs and bullae consisted of accumulated thick and fine fibers. Accumulated thick elastic fibers showed vacuolar changes and electron-dense granular deposits, and they were associated with spiraling collagen fibrils. These thick elastic fibers reacted evenly with antielastin antibody and also reacted with anti-alpha 1-antitrypsin antibody. They are thought to be degraded elastic fibers. Accumulated fine elastic fibers consisted of bundles of microfibrils and granular amorphous components, and they reacted with anti-elastin and anti-alpha 1-antitrypsin antibody. These fine elastic fibers are thought to be not only newly formed in the process of organization but also degraded. It is suggested that elastic fibers of blebs and bullae are degraded due to an imbalance between elastase and alpha 1-antitrypsin.

Adult↗
PubMed1993

Pathologic and laboratory dynamics following the removal of the shunt in shunt nephritis.

Membranoproliferative glomerulonephritis (type 1) associated with infected ventriculoatrial shunt was observed in an 11-year-old girl. The removal of the shunt and antimicrobial therapy led to rapid improvement in the clinical symptoms, serologic abnormalities, and glomerular alterations. Serum complement levels were initially low and returned to normal values within 1 month. Urinary sediment abnormalities resolved within a few months. Cultures taken from cerebrospinal fluid and the end of the shunt grew Staphylococcus epidermidis. Initial renal biopsy obtained immediately before shunt removal showed membranoproliferative glomerulonephritis (type 1). Repeat biopsy performed 2 years after shunt removal showed moderate improvement of glomerular alterations. This study of pathologic and laboratory changes following therapy suggests that the pathophysiology of the nephritis was based on an immunologic process, and that removal of antigen resulted in reversal of glomerular changes.

Biopsy↗
PubMed1993

Amidinopiperidine-4-carboxylic acid 4-tert-butylphenyl ester, a trypsin inhibitor, suppresses the onset of DNA synthesis in HeLa cells synchronized by a double-thymidine block.

Release of HeLa cells arrested at the G1/S boundary by double-thymidine block caused abrupt uptake of [methyl-3H]thymidine into DNA after 5 min, and two sharp high activity peaks, peak I and peak II, were observed 8 and 23 min after removal of the thymidine block and this was followed by a gradual uptake of [3H]thymidine. The duration of the cell cycle was 23 h, and definite changes in cell density were observed between 12 and 13 h and also between 35 and 36 h after removal of the thymidine. Addition of amidinopiperidine-4-carboxylic acid 4-tert-butylphenyl ester (APCA-OPh'Bu), a trypsin inhibitor, immediately after removal of the arrest strongly suppressed DNA synthesis and mitosis. In contrast, addition of APCA-OPh'Bu 10 min after removal of the arrest, and hence also after the appearance of peak I, had no effect on peak II nor on the uptake of thymidine occurring during the remainder of the first cell cycle, nor on mitosis. However, it strongly suppressed the second DNA synthesis and mitosis. These results suggest participation of a trypsin-like proteinase at the onset of DNA synthesis. Removal of thymidine from the arrested cells at a cell density of 2% (4 x 10(3) cells/cm2) induced an immediate and rapid rise in trypsin-like proteinase activity. However, the activity decreased with increasing cell density. No clear increase in the activity was seen at a cell density of 20% (4 x 10(4) cells/cm2). However, both trypsin-like proteinases obtained at cell densities of 2% and 20% were strongly inhibited by APCA-OPh'Bu and these inhibitory effects were similar.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Cycle↗
PubMed1993

[Chemical fluctuation of the constituents during the drying of Ginseng radix and Ginseng radix Rubra. Crude drug processing by far-infrared treatment].

In order to evaluate the utility of far-infrared drying method for crude drugs, the efficiency in the drying process of Ginseng Radix and Ginseng Radix Rubra was examined. Furthermore, chemical fluctuation of the constituents of Ginseng Radix and Ginseng Radix Rubra, which may occur during their drying process, has been investigated by means of HPLC quantitative analysis for ginsenosides and malonyl-ginsenosides, and TLC qualitative analysis for lipophylic constituents. It has been found that the far-infrared drying method (oven temperature 45 degrees C) dried Ginseng Radix faster without reducing both ginsenosides and malonyl-ginsenosides in comparison with the conventional drying methods such as an air drying and a hot-air drying.

Chromatography, High Pressure Liquid↗
PubMed1993

Interactions of elastin and microfibrils in elastogenesis of human pulmonary fibroblasts in culture.

The interaction of elastin and microfibrils in elastogenesis in vitro was investigated with electron microscopy and immunohistochemistry. Fetal human pulmonary fibroblasts were cultured with or without beta-aminopropionitrile (BAPN). One week after seeding, the extracellular microfibrils were loosely arranged without elastin deposition. Two and six week culture in controls, mature elastic fibers and microfibril bundles were formed. In cultures with BAPN, the microfibrils were loosely arranged, and a few microfibril bundles and no amorphous components were formed. Immunoelectron microscopy for elastin showed the reaction at the outer zones of amorphous components in controls, though the loosely-arranged microfibrils reacted diffusely in cultures with BAPN. Six week culture with BAPN, aggregated masses of elastin, which were dissociated from microfibrils, were found. In conclusion, deposition and maturation of elastin on microfibrils are necessary to form the microfibril bundles in normal elastogenesis, and vaguely outlined aggregated masses of elastin are formed under the inhibition of lysyl oxidase.

Aminopropionitrile↗
PubMed1993

[Ultrasonic diagnosis of renal cell carcinoma in hemodialysis patients].

Abdominal ultrasonic examination (US) was performed in 1556 patients on hemodialysis for 7 years and 6 months from April 1955 to September 1992. Renal cell carcinoma (RCC) proved histologically by operation was found in 36 patients (41 kidneys). Among the 36, RCC developed from the contracted kidney in 15, the individual kidney after renal transplantation in 3, and from ACDK (acquired cystic disease of the kidney) in 18. Among the 18 (ACDK), multiple tumors were found in the unilateral kidney in 8 and in bilateral kidney in 5. RCC was detected at the rate of 2.3% in patients on hemodialysis (1 out of 43). It was 29 time as high as in healthy persons (RCC was found in 22 out of 27933 at our Health Check-up Center, 0.079%). RCC was diagnosed 100% by US, 68% by CT, and 55% by angiography. US is the most excellent examination for the diagnosis of RCC in patients on hemodialysis.

Abdomen↗
PubMed1993

DNA conformation polymorphism analysis of DR52 associated HLA-DR antigens by polymerase chain reaction: a simple, economical and rapid examination for HLA matching in transplantation.

HLA-DRB1 and -DRB3 alleles of DR52-associated (DR52ass) HLA-DR antigens were genotyped by a polymerase chain reaction (PCR) - based simple and practical method. Genomic DNAs from two hundred Japanese panels were subjected to PCR with two pairs of primers to separately amplify the DR52ass-DRB1 (DR3, 5, 6, and 8) alleles and DRB3 (DR52) alleles. The specific amplification revealed that 128 and 76 panels possessed DR52ass alleles and DRB3 alleles, respectively. PCR products from these panels were heat-denatured, electrophoresed in a non-denaturing polyacrylamide gel, and visualized by silver staining. Electrophoretic mobilities of the DNA samples were compared with those of the typing standards with known genotypes of DR52ass-DRB1 and DRB3 alleles. This method, designated PCR-DNA conformation polymorphism (DCP) analysis, allowed genotyping of the DR52ass-DRB1 and DRB3 alleles of panels without any sequence-specific oligonucleotide probe (SSOP) or restriction endonuclease, and the entire process after PCR could be completed within a few hours. Because the DR52ass-DRB1 and DRB3 alleles assigned by this method were shown to be identical to those determined by the PCR-SSOP method, PCR-DCP analysis was suggested to be a simple and practical HLA genotyping method.

Alleles↗
PubMed1993

[Effects of a synthetic progestin on ventilatory response to hypoxia in awake male rats].

The effect of progesterone is most likely exact by directly stimulating the central nervous system. However, it remains unclear whether progesterone and/or estrogen act through the peripheral chemoreceptor. The carotid body is thought to be the sole sensing organ of hypoxia. The present study was conducted to determine whether administration of female hormones, i.e., progestin and/or estrogen, augment ventilatory response to hypoxia in the awake male Wistar rat. The combined administration of a synthetic progestin (TZP 4238) and estradiol for 5 days significantly increased tidal volume and minute ventilation, reduced arterial PCO2, and enhanced the ventilatory response to hypoxic gas inhalation. Augmentation of hypoxic ventilatory response was achieved by a increment of respiratory rate with a shortening of expiratory time. Administration of either TZP 4238 or estradiol alone or vehicle had no effects on respiratory variables. Our results suggest that female hormones may act through the peripheral chemoreceptor as well as the central nervous system.

Animals↗
PubMed1993

[The role of eradication of Helicobacter pylori in healing and recurrence of gastric ulcer].

It is now generally accepted that infection with Helicobacter pylori is the most common cause of active chronic gastritis and duodenal ulceration. Although H. pylori is detected in the majority of patients with gastric ulcer, its pathogenicity and role in gastric ulceration remains unclear. One method to study this relationship is to eradicate H. pylori and observe the recurrence of gastric ulcer. In the present paper we examined the consequence of H. pylori eradication by antibiotics mono therapy with histamine H2 receptor antagonist on the recurrence of gastric ulcer. Two cases treated with proton pump inhibitor plus clarithromycin were reported. It is concluded that eradication of H. pylori infection may diminish the recurrence of gastric ulcers.

Aged↗