Biomedical subjects

Y Fujii

Publications and source records attributed to Y Fujii.

At least 631 records · Page 35Linked to original sources

PubMed1994

Bcl-2 expression in the thymus and periphery.

Bcl-2 proto-oncogene is expressed in normal lymphoid tissues and its role has been suggested to involve the selection of B and T cells. Here we report three-color flow cytometric studies on the expression of bcl-2 protein in the thymus and periphery. Bcl-2 was expressed in the majority of T and B cells and down-regulated only in the CD1+, CD3- to low, CD4+8+ thymocytes, and the B cells that are in cell cycle in the tonsil and lymph node. In contrast, the CD2+, CD1-3-4-8-19-, early T cells, and mature single positive cells in the thymus, as well as the tonsilar and lymph node T cells, irrespective of their cell cycle status, expressed bcl-2. These results are consistent with the notion that bcl-2 is down-regulated in the T and B cells that are in the process of generating new antigen receptors and subject to subsequent positive selection.

Adult↗

PubMed1994

X-ray microanalysis of rat mast cells stimulated with compound 48/80 in combination with quick-freezing method.

X-ray microanalysis was performed on rat mast cells prepared by quick-freezing, cryosectioning and freeze-drying (QF-FD) method, or quick-freezing and freeze-substitution (QF-FS) method. Peritoneal cells including mast cells were stimulated with compound 48/80 for 0, 10 or 30 s at 17 degrees C, and the mast cells stimulated for 30 s started exocytosis. In X-ray spectra of the QF-FD specimen, mast cells stimulated for 10 s increased their levels of phosphorus, sodium and chlorine in the intergranular cytoplasm prior to exocytosis, and kept this increase until 30 s after stimulation. In the QF-FS specimen, where soluble elements were removed, peaks of phosphorus, sulphur and potassium could be detected as elements in X-ray spectra. Phosphorus increased and potassium decreased in intergranular cytoplasm of mast cells stimulated for 10 s, and these changes became more obvious after 30 s. However, supplemental increase of other cations such as sodium could not be detected in the QF-FS specimens.

Animals↗

PubMed1994

Ultrastructural study of mast cells stimulated with compound 48/80 as revealed by quick-freezing method.

The ultrastructure of mast cells stimulated with compound 48/80 was examined by quick-freezing and deep-etching (QF-DE) or freeze-substitution (QF-FS) methods. Peritoneal cells including mast cells of adult male rats were stimulated in vitro with compound 48/80 at 17 degrees C for 0, 10, 30, 60 or 180 s. The QF-DE replicas revealed that the mast cells stimulated with compound 48/80 for 30 s decreased filamentous actin around secretory granules. In the QF-FS specimens, perigranular membranes in mast cells stimulated for 60 s formed pentalaminar structures between adjacent granules in their cytoplasm prior to degranulation. These findings suggest that preparatory states for degranulation occur in the whole cytoplasm of stimulated mast cells at early stages. Moreover, both QF-FS specimens and QF-DE replicas revealed a compact morphological appearance of discharged granules in the extracellular space, indicating the existence of considerable content within the granules. Skeletal structures in the granules were also demonstrated on QF-DE replicas prepared after extracting soluble elements from the cytoplasm. It is suggested that the granular contents associated with the skeletal structures are gradually detached from the discharged granules to ensure local concentration in the tissues.

Animals↗

PubMed1994

Morphological study of rat mast cells stimulated with compound 48/80 at different temperatures.

Changes of mast cells stimulated with compound 48/80 were morphologically investigated at different temperatures. Peritoneal mast cells of male rats were stimulated in vitro at 4 or 17 degrees C. At 17 degrees C, mast cells stimulated for 10 s gave decreased fluorescent reactions for phalloidin. At 30 s stimulation, they showed typical exocytosis initiated by fusions of peripherally located secretory granules to the plasma membrane. In contrast, mast cells stimulated at 4 degrees C exhibited neither decrease of phalloidin reactions nor typical excytosis even after 30 s. It was inferred that the fusions were mediated by cytoplasmic elements, probably the actin filaments previously suggested to prevent release of secretory granules. Furthermore, the space between the perigranular membrane and granular contents was enlarged in some mast cells stimulated at 4 degrees C. The morphological changes suggested that equivocal events occurred also in the cytoplasm of these cells. The mast cells showed no typical exocytosis at 4 degrees C.

Animals↗

PubMed1994

Hydrophilic polymer-coated guide wire combined with progressive suppleness pursil catheter for safer, more definitive embolisation of arteriovenous malformations.

For safe, more definitive embolisation of arteriovenous malformations, improved selectivity of the catheter is desirable. This report describes the advantage of the combined use of a progressive suppleness pursil catheter and a hydrophilic polymer-coated guide wire, together with precaution against complications. In 14 patients, 27 vessels were catheterised with this. Chemical embolisation using oestrogen alcohol and polyvinyl acetate was carried out only if sufficiently superselective catheterization was achieved with negative results on a provocation test. Chemical embolisation was successful in 25 vessels, but in three vessels catheterised very distally, it required much more time to withdraw the catheter because of the friction between it and the wall of the vessel.

Adolescent↗

PubMed1994

A targeting model of boron neutron-capture therapy to hepatoma cells in vivo with a boronated anti-(alpha-fetoprotein) monoclonal antibody.

We described previously that 10B atoms delivered by monoclonal antibody (mAb) exerted a cytotoxic effect on AH66 cells in a dose-dependent manner upon thermal neutron irradiation in vitro. In the present study, the delivering capacity of boronated anti-(alpha-fetoprotein) (AFP) mAb to carry 10B atoms to AFP-producing tumor xenografts in nude mice was determined. Boronated mAb was prepared by conjugating 50 mM 10B compound to an anti-AFP mAb (2 mg/ml) using N-succinimidyl-3-) (2-pyridyldithio) propionate. The number of 10B atoms conjugated directly to the mAb was estimated to be 459/antibody by prompt gamma-ray spectrometry. Boron concentrations in tumor tissue obtained 12, 24, 72, and 120 h after injection of 3.0 mg 10B-conjugated anti-AFP mAb were 11.10 +/- 3.12 (SD, n = 6). 29.30 +/- 5.11, 33.02 +/- 11.8, and 12.91 +/- 5.62 ppm respectively. For control 10B-conjugated anti-dinitrophenol (DNP) mAb, the values were 9.59 +/- 0.99, 10.37 +/- 2.86, 10.00 +/- 2.95, and 8.83 +/- 4.71 ppm respectively. The concentrations in blood were less than 0.40 +/- 0.10 ppm with anti-AFP mAb and less than 0.51 +/- 0.15 ppm with anti-DNP mAb at each sampling time (12, 24, 72, and 120 h). The number of 10B atoms delivered to the tumor cells was calculated to be 0.62 x 10(9), 1.63 x 10(9), 1.84 x 10(9) and 0.72 x 10(9) at each sampling time after injection of 10B-anti-AFP mAb. The amount of 10B atoms necessary for effective boron neutron-capture therapy was estimated to be 10(9)/tumor cell. We were able to carry 1.84 x 10(9) 10B atoms to AH66 tumor cells by using 10B-anti-AFP mAb. The accumulation reached its peak 72 h after injection. These data indicated that the 10B-conjugated antitumor mAb could deliver a sufficient amount of 10B atoms to the tumor cells to induce cytotoxic effects 72 h after injection upon thermal neutron irradiation.

Animals↗

PubMed1994

A field isolate of Sendai virus: its high virulence to mice and genetic divergence form prototype strains.

A field isolate of Sendai virus, the Hamamatsu strain, was far more virulent in mice than the prototype Z strain. The Hamamatsu strain replicated more efficiently in the mouse lung than the Z strain, causing deteriorating lung lesions. Nucleotide sequence analysis of the HN, F and M genes revealed that the Hamamatsu strain was divergent from the prototype Z, Harris and Fushimi strains.

Animals↗

PubMed1994

Nicardipine enhances diaphragmatic fatigue.

The effects of nicardipine, a calcium channel blocker, on diaphragmatic fatigue were studied in 20 anaesthetized, mechanically ventilated dogs divided into two groups: control group (Group C, n = 10) and nicardipine group (Group N, n = 10). Diaphragmatic fatigue was induced by intermittent supramaximal electric stimulation to bilateral phrenic nerves at a frequency of 20 Hz for 30 min. In Group N, 5 micrograms.kg-1.min-1 nicardipine iv was infused continuously during this fatigue-producing period. Transdiaphragmatic pressure (Pdi) produced by electrical stimulation (10-100 Hz) of the phrenic nerves was used as an index of diaphragmatic contractility. After a fatigue-producing period, the Pdi in both groups decreased at low frequency (10-30 Hz) stimulation compared with pre-fatigue values (P < 0.05), whereas no change in Pdi was observed at high-frequency (50-100 Hz) stimulation. The decrease of Pdi at low-frequency stimulation was larger in Group N (P < 0.05). The integrated diaphragmatic electric activity (Edi) in both groups did not change at any frequency of stimulation throughout the experiment. We conclude that nicardipine enhances diaphragmatic fatigue.

Animals↗

PubMed1994

Reduction of postoperative nausea and vomiting with granisetron.

The antiemetic effects of granisetron, a selective 5-hydroxy-tryptamine type 3 receptor antagonist, on postoperative nausea and vomiting were studied and compared with placebo and metoclopramide in 60 patients undergoing general anaesthesia for major gynaecological surgery. The patients received a single i.v. dose of either granisetron (3 mg, n = 20) metoclopramide (10 mg, n = 20), or placebo (saline, n = 20) immediately after recovery from anaesthesia. The effects were assessed during the first three and the next 21 hr after recovery from anaesthesia by means of a nausea and vomiting score; 0 = no emetic symptoms, 1 = nausea, 2 = vomiting. The mean scores during 0-3 hr were 0.8, 0.1 and 0.1 after administration of placebo, metoclopramide and granisetron, respectively; the corresponding scores during 3-24 hr were 0.6, 0.5 and 0.1. The scores of the metoclopramide and the granisetron groups were different from the placebo group in the first three hours (P < 0.05). Although there were no differences in the scores during 0-3 hr between the metoclopramide and the granisetron groups, there were differences during 3-24 hr (P < 0.05). It is concluded that granisetron is superior to metoclopramide in the long-term prevention of postoperative nausea and vomiting after anaesthesia.

Adult↗

PubMed1994

Optimal anti-emetic dose of granisetron for preventing postoperative nausea and vomiting.

In order to determine the optimal effective dose of granisetron for preventing postoperative nausea and vomiting, the drug was administered in doses of either 20, 40 or 60 micrograms.kg-1. The efficacy of granisetron was evaluated in a randomized, double-blind comparison with placebo in 100 patients undergoing general anaesthesia for major gynaecological surgery. The patients received a single dose of either granisetron or placebo (saline) iv immediately after recovery from anaesthesia. The effects were assessed during the 24 hr after recovery from anaesthesia by means of a nausea and vomiting score; 0 = no emetic symptoms, 1 = nausea, 2 = vomiting. The treatment groups were similar for patient characteristics, surgical procedures and anaesthetics administered. The mean scores were 0.7, 0.6, 0.2 and 0.2 after administration of placebo, granisetron 20, 40 and 60 micrograms.kg-1, respectively. Granisetron 40 micrograms.kg-1 was as effective as 60 micrograms.kg-1 and both resulted in reduction of the scores compared with placebo and granisetron 20 micrograms.kg-1 (P < 0.05). In conclusion, granisetron 40 micrograms.kg-1 is considered to be the appropriate dosage for preventing postoperative emesis after anaesthesia.

Adult↗

PubMed1994

Plication of paralyzed hemidiaphragm after right sleeve pneumonectomy.

Right diaphragmatic plication was performed in a 62-year-old man who underwent right sleeve pneumonectomy and then required prolonged mechanical ventilation owing to right diaphragmatic paralysis. The plication was very effective in allowing him to be weaned from the ventilator. The transdiaphragmatic pressure, the ratio of gastric to esophageal pressure swing, and the work of breathing per liter of ventilation improved remarkably after plication. Our experience indicates the beneficial effect of such a plication on contralateral lung function from the standpoint of clinical and respiratory mechanics.

Carcinoma, Squamous Cell↗

PubMed1994

Involvement of oxygen radicals in the differentiation of rat myelomonocytic leukemia cells in vitro and in vivo.

We have found that LPS induces the differentiation of an LPS-resistant subline (LR) of rat myelomonocytic leukemia cell line, c-WRT-7, in vivo, which are resistant to the differentiation inducing effects of LPS in vitro. Furthermore, we have found that the differentiation of LR cells induced by LPS is inhibited by superoxide dismutase, which is one of radical scavengers. Accordingly, we have examined the differentiation inducing effects of xanthine oxidase, a potential source of oxygen radicals, on LR cells in vitro and in vivo. Xanthine oxidase induced the differentiation of LR cells into macrophage-like cells in vitro; and superoxide dismutase inhibited the differentiation of LR cells induced by xanthine oxidase both in vitro and in vivo. These results suggest that oxygen radicals are involved in the differentiation inducing effects of LPS.

Animals↗

PubMed1994

Induction of oral tolerance after feeding of ragweed pollen extract in mice.

The induction of oral tolerance following the feeding of ragweed pollen and its extract was investigated in BALB/c mice. Antibody class-specific immune suppression could be observed, and the IgE response was specifically suppressed, depending on the amount of ragweed pollen extract fed when subsequently immunized with ragweed extract together with A1(OH)3 as an adjuvant. A multiple feeding was more effective than a single feeding of antigen, and the IgE response was completely suppressed when 20 mg of pollen extract was fed for 5 consecutive days. On the other hand, IgG production was not suppressed even though a large amount of ragweed pollen or its extract was fed. Furthermore, no secretion of antigen-specific IgA into saliva was observed in control animals or those fed ragweed pollen extract. Thus, pollen extract feeding may be potentially useful for the prophylaxis or therapy of allergic rhinitis induced by ragweed.

Administration, Oral↗

PubMed1994

Development and evaluation of oral reporting system for PACS.

Experimental workstations for oral reporting and synchronized image filing have been developed and evaluated by radiologists and referring physicians. The file media is a 5.25-inch rewritable magneto-optical disk of 600-Mb capacity whose file format is in accordance with the IS&C specification. The results of evaluation tell that this system is superior to other existing methods of the same kind such as transcribing, dictating, handwriting, typewriting and key selections. The most significant advantage of the system is that images and their interpretation are never separated. The first practical application to the teaching file and the teaching conference is contemplated in the Osaka University Hospital. This system is a complete digital system in terms of images, voices and demographic data, so that on-line transmission, off-line communication or filing to any database will be easily realized in a PACS environment. We are developing an integrated system of a speech recognizer connected to this digitized oral system.

Education, Medical↗

PubMed1994

Recipient-mediated effect of a traditional Chinese herbal medicine, ren-shen-yang-rong-tang (Japanese name: ninjin-youei-to), on hematopoietic recovery following lethal irradiation and syngeneic bone marrow transplantation.

Ren-shen-yang-rong-tang (Japanese name: Ninjin-youei-to, NYT), a traditional Chinese herbal medicine, was evaluated for recipient-mediated effect on hematopoietic recovery in a murine model of syngeneic bone marrow transplantation (BMT). BALB/c recipient mice were preconditioned with a lethal total body irradiation (TBI) at a dose of 6.5 Gy and transplanted with syngeneic bone marrow (BM) cells. NYT treatments, given intraperitoneally (i.p.) once per day for 3 consecutive days in a dose of 0.625 mg, were performed either before or after TBI and BMT to assess any recipient-mediated effect of this compound. NYT pretreatment was as effective as NYT posttreatment in enhancing the total number of colony-forming unit erythroid (CFU-E) and colony-forming unit granulocyte-macrophage (CFU-GM) per marrow and spleen after TBI and BMT. NYT pretreatment caused a significant increase in marrow and splenic CFU-E and CFU-GM numbers over a prolonged period following TBI and BMT, and affected late-stage erythropoiesis (CFU-E) more profoundly than early-stage erythropoiesis (burst-forming unit erythroid, BFU-E). NYT pretreatment significantly accelerate recovery of not only erythrocyte and leukocyte counts but also platelet counts after transplantation with a limited number (1 x 10(5)) of BM cells. The same treatment, however, was significantly less effective in hematopoietic recovery after transplantation with a minimal number (1 x 10(4)) of BM cells, indicating that NYT accelerates recovery of donor-derived rather than recipient-derived cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1994

Activation of systemic and mucosal immune response following nasal administration of liposomes.

Adjuvant effects of liposomes on systemic and mucosal immune response were investigated following nasal administration to Balb/c mice. Bovine serum albumin (BSA)-specific serum IgG and salivary IgA levels were significantly elevated when BSA-associated liposomes were administered intranasally twice at 4-week intervals. Systemic immune response was activated only by negatively charged liposomes, while activation of mucosal immune response was independent of liposomal charge. Antigen localization in liposomes affected immune adjuvant effect; the mucosal immune response could be activated only by liposomes to whose surface BSA was attached, but the systemic immune response was activated by both liposomes to which antigens were attached and in which the encapsulating antigens occurred. The results suggest that the contribution of antigen-presenting cells in activation of systemic and mucosal immunity following intranasal administration is different.

Adjuvants, Immunologic↗

PubMed1994

Mitochondrial dysfunction during anoxia/reoxygenation injury of liver sinusoidal endothelial cells.

Sinusoidal endothelial cell injury plays a pivotal role in anoxia/reoxygenation liver damage. However, the mechanisms culminating in anoxia/reoxygenation endothelial cell injury remain unclear. Our aims were to determine whether anoxia/reoxygenation injury of sinusoidal endothelial cells causes mitochondrial dysfunction. In cultured rat liver sinusoidal endothelial cells, the mitochondrial membrane potential, cytosolic free calcium and cytosolic pH were quantitated by means of fluorescent probes and multiparameter digitized video microscopy. Cell viability was measured on the basis of lactate dehydrogenase release, and ATP was quantitated with a luciferin/luciferase assay. Mitochondrial membrane potential was stable during 90 min of aerobic perfusion. After 60 and 90 min of anoxia, mitochondrial membrane potential decreased gradually to 97% +/- 6% and 79% +/- 7% of the basal value, respectively. However, mitochondrial membrane potential decreased abruptly with reoxygenation after 60 min of anoxia to 45% +/- 12% of the basal value and did not recover over 30 min of aerobic perifusion. Loss of mitochondrial membrane potential could not be attributed to changes of cytosolic free calcium, cytosolic pH, nitric oxide generation or activity of poly(ADP-ribose) polymerase.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Triphosphate↗

PubMed1994

Corpus callosum development in preterm and term infants.

The development of the corpus callosum was documented by magnetic resonance imaging in low-risk preterm infants and results were compared with those of term infants. Thirty-three magnetic resonance imaging studies were performed on 21 preterm infants whose corrected ages were 1-13 months. Twenty-one magnetic resonance imaging studies were performed on 17 term infants. All infants exhibited normal development. The thickness of the corpus callosum was measured at a point one-third of the length of the entire corpus callosum from the most anterior aspect of the genu. The thickening of the corpus callosum was related to age in the preterm group. The development of the corpus callosum in preterm infants was suggested to be the same as that of term infants matched by conceptional age.

Birth Weight↗