Biomedical subjects

M Okazaki

Publications and source records attributed to M Okazaki.

At least 235 records · Page 13Linked to original sources

PubMed1996

Hepatic Fas antigen expression before and after interferon therapy in patients with chronic hepatitis C.

To assess the relationship between hepatitis C virus infection and Fas antigen expression on hepatocytes, we examined changes in hepatic Fas antigen expression in the presence or absence of active hepatitis C virus infection. Twenty patients with chronic hepatitis C infection were treated with interferon and underwent pre- and posttreatment liver biopsies. Patients were classified according to the absence (group A; n = 9) or the presence (group B; n = 11) of hepatitis C virus RNA (HCV-RNA) in the liver after interferon therapy. An immunohistochemical assay showed Fas antigen staining in hepatocytes membranes and cytoplasm with expression concentrated mainly in periportal areas. The percentage of Fas-positive cells in the liver before treatment was not different between group A (39.5+/-19.1%) and group B (32.5+/-15.6%). Hepatic Fas expression was reduced significantly after treatment (24.3+/-10.6%) compared with the pretreatment values in group A (p < 0.05) but not in group B (25.9+/-16.9%). There was no significant difference between the two groups in the degree of histologic improvement. These results suggest that hepatic Fas expression is associated with persistent infection of hepatitis C virus.

Adult↗

PubMed1996

Tumor-specific accumulation of 125I-labeled mouse-human chimeric anti-CEA antibody in a xenografted human cancer model demonstrated by whole-body autoradiography and immunostaining.

Whole-body autoradiography (WBAR) was used to study the biodistribution of 125I-labeled mouse-human chimeric antibody (Ch F11-39) to carcinoembryonic antigen (CEA) in athymic nude mice bearing the CEA-producing MKN-45 human gastric carcinoma xenografts. Significantly high uptake of 125I-Ch F11-39 in the tumors obtained by tissue-counting technique was confirmed by WBAR of mice of 12, 24, 48, and 96 h postinjection of 125I-Ch F11-39. When compared with histochemical or immunohistochemical staining results of the tumor tissue sections, imaging profiles of 125I-Ch F11-39 obtained by WBARs were topographically correlated with histopathological findings of tissues and immunohistochemical localization of CEA in the tumor tissues, indicating that the accumulation of 125I-Ch F11-39 at the tumor site is based on its specificity for CEA. These results demonstrate that this chimeric antibody may serve as a potential useful diagnostic and/or therapeutic reagent for human CEA-producing cancers.

Animals↗

PubMed1996

Endoscopic excision of large capsulated lipomas.

The technique of endoscopic excision of large capsulated lipomas is presented and the versatility of this method is discussed based on our clinical experience. We have applied this new technique in 6 cases. In all cases the lipoma was completely removed in one piece through a single incision, up to 1.5 cm in length. The endoscope made it possible to view the lipoma through a narrow space with a wide range of vision on a TV monitor. We stress that this method is not only appropriate as treatment for benign lipomas but also effective from a cosmetic point of view. The applications of the endoscope should widen in plastic surgery when the advantages of it are recognized and new operative approaches for using it are developed.

Adult↗

PubMed1996

[Study on septicaemia in infants and children in the past 20 years. Part 1. An analysis of causal organisms].

Causal organisms and their changes were evaluated in 158 cases of septicaemia admitted to Jikei University Hospital from 1975 to 1994. Eighty patients (50.6%) were aged less than 1 year, and 37 patients (23.4%) were newborns. The average mortality rate was 18.4%. The mortality rate between 1975 and 1984 was 26.8%, and that of the past 10 years (from 1985 to 1994) decreased to 13.7%. Staphylococcus aureus (29 cases, 19.4%) was the most common pathogens isolated, followed by Pseudomonas sp. (24 cases, 15.2%), Escherichia coli (19 cases, 12.0%), and Haemophilus influenzae (18 cases, 11.4%). H. influenzae, Acinetobacter sp., Streptococcus pneumoniae and Group B streptococcus (GBS) increased in the past 10 years (from 1985 to 1994), compared with the preceding 10 years (from 1975 to 1984). The mortality rate of Klebsiella sp. septicaemia (28.6%) was highest, followed by Pseudomonas sp. (25.0%), S. aureus (24.1%), S. pneumoniae (22.2%). H. influenzae and Acinetobacter sp. septicaemia were not fatal. E. coli and GBS were common among neonates and patients aged less than 1 year. H. influenzae septicaemia occurred mainly in patients with meningitis, in those younger than school age. Acinetobacter sp. was common among neonates and children with leukaemia Pseudomonas sp., Klebsiella sp., and Acinetobacter sp. were mainly detected in patients with underlying diseases. E. coli, H. influenzae, S. pneumoniae and GBS were mainly detected in patients without underlying diseases.

Adolescent↗

PubMed1996

[Study on septicaemia in infants and children in the past 20 years. Part 2. An analysis of factors that prescribe for the prognosis].

Underlying diseases, complications, clinical findings, and laboratory findings were evaluated in 158 cases of septicaemia admitted to Jikei University Hospital from 1975 to 1994, in order to conjectured factors that prescribe for the prognosis. 50% of the patients had underlying diseases. Malignancy including leukaemia (31 cases, 39.2%) was the most common underlying disease, followed by low birth weight infant (17 cases, 21.5%), aplastic anemia (9 case, 11.4%), and congenital heart disease (7 cases, 8.9%). The death rate for patients with underlying disease (27.8%) was significantly greater than the mortality for normal patients with septicaemia (8.9%) (p < 0.05). Meningitis (24.7%) was the most common complication, followed by DIC (19.6%), shock (15.2%), and pneumonia (10.8%). The mortality rate of septicaemia complicated by shock was 66.7% (p < 0.01), and that complicated by DIC was 45.2% (p < 0.01). The mortality rate for patients with the clinical findings of respiratory distress, cough, abdominal distention, cyanosis, splenomegaly, or peripheral coldness was more than 40% and significantly greater (p < 0.01). Mortality rate in patients with granulocyte counts of < 4.000/mm3, platelet counts of < 5 x 10(4)/ mm3, total protein of < 5.0 g/dl, or ESR of < 20 mm/hr were significantly greater (p < 0.01) than those in patients with normal laboratory findings. Coincidence rate of blood and stool cultures was 57.9% for E. coli, and 28.6% for Klebsiella sp., and that of blood and throat cultures was more than 30% for Pseudomonas sp., Haemophilus influenzae, and Staphylococcus aureus. In the study of antimicrobial susceptibility for microorganisms isolated, the number of drug resistant S. aureus had increased in the last 10 years.

Adolescent↗

PubMed1996

Impaired cAMP-mediated gene expression and decreased cAMP response element binding protein in senescent cells.

The capacity of various growth factors to induce c-fos expression is diminished with senescence. Because adenosine 3',5'-cyclic monophosphate (cAMP)-mediated responses are also blunted with aging, we wondered whether cAMP-induced c-fos gene expression might be impaired with senescence. Using IMR fibroblasts, we found that prostaglandin E1 (PGE1) and forskolin, stimulators of cAMP accumulation in young and senescent cells, increased abundance of c-fos and junB mRNA more in young than senescent cells. The abundance of the cAMP response element binding protein (CREB), a transcription factor which enhances gene expression when phosphorylated by protein kinase A, was markedly decreased in both whole cell and nuclear extracts of senescent cells, in both Western blotting and in gel retardation assays. Also, PGE1-induced phosphorylation of CREB by protein kinase A was markedly attenuated in senescent cells. There is a marked decrement in expression of CREB with senescence, and the results suggest the possibility that the diminished expression of CREB may contribute to altered cAMP-mediated regulation of gene expression with senescence.

Aging↗

PubMed1996

Size and asymmetry of the planum temporale. A new three-dimensional method for analysis of the supratemporal plane using MR imaging and computer-aided graphics.

The planum temporale of the supratemporal plane is important for language function and shows left-right asymmetry in most brains. To estimate the size and allow side comparison of the planum temporale, we developed a new technique for 3-D MR analysis of the supratemporal plane using a personal computer and computer-aided graphics. The temporal lobes of 5 human cadavers were imaged by MR in the sagittal plane, at a slice thickness of 2 mm. The images of the supratemporal plane were entered into a personal computer using the original software to determine the positions of anatomic landmarks and the size of the planum temporale. The data were then transferred to a supercomputer to reconstruct the 3-D surface image of the supratemporal plane. Computer images of the supratemporal plane agreed with macroscopic observations. The positions of anatomic landmarks and the size of the planum temporale also agreed with macroscopic measurements. Thus, the present technique provides valuable anatomic data on the supratemporal plane which should be useful for further clarification of the anatomic basis of language function.

Adult↗

PubMed1996

Properties of heterogeneous apatites containing magnesium, fluoride, and carbonate.

Biological apatites present in the mineral phases of normal and pathological calcifications contain magnesium, Mg, and carbonate, CO3. As a consequence of fluctuations in the composition of the micro-environment, these apatites may sometimes form by heterogeneous precipitation. The purpose of this study was to investigate the properties of (Mg, CO3)-apatites formed heterogeneously in the presence of fluoride, F. Two types of fluoridated (Mg, CO3)-apatites formed from solutions with low and high levels of Mg were prepared at 80 degrees C, pH 7.4. We prepared FMgCO3-MgCO3AP (Type 1) by adding the F-containing solution to those containing calcium, Mg, and phosphate ions during the first half of the precipitation period. We prepared MgCO3-FMgCO3Ap (Type 2) by adding the F-containing solution during the final half of the period. The apatites were analyzed by x-ray diffraction (XRD), infrared absorption spectroscopy, and scanning electron microscopy (SEM). SEM and XRD analyses showed evidence of mixed crystals in the heterogeneous apatites. The presence of Mg inhibits, while F promotes, apatite crystal growth. In addition, Mg incorporation increased with increasing fluoride concentration. The extent of dissolution in acid buffer of both types of heterogeneous apatites increased with Mg: Type 1 > Type 2. These results suggest that the crystal and dissolution properties of heterogeneous fluoridated (Mg, CO3)-apatites are greatly affected by the mode of F incorporation and Mg concentrations in the environment.

Apatites↗

PubMed1996

Polyanion induced preferential multinucleation in macrophages at a low level of TNF-alpha secretion.

When rat bone marrow macrophages were incubated with acetyl lignin (EP3) in the presence of a 10% solution of fetal bovine serum, the macrophages secreted tumor necrosis factor (TNF-alpha) in a dose-dependent manner. This was followed by macrophage multinucleation. EP3 was found to have a significant effect on TNF-alpha secretion at a minimum dose of 5 micrograms/ml and produced no significant further increase at levels above 50 micrograms/ml, while multinucleation was most active at 10 micrograms/ml. However, multinucleation did not occur at higher concentrations of EP3 (50 micrograms/ml and 100 micrograms/ml). Secretion of TNF-alpha was significantly reduced in the absence of fetal bovine serum, whereas multinucleation was very active, starting after 6 h of incubation. At concentrations of 100 micrograms/ml, sulfonyl lignin (LS) and dextran sulfate (DS) only induced low levels of TNF-alpha secretion from macrophages, but induced active multinucleation. The multinucleation induced by addition of LS or DS was inhibited by further addition of EP3. Thus, macrophage multinucleation was most active when a low level of TNF-alpha was secreted from the macrophages.

Animals↗

PubMed1996

Signal transduction pathway on beta-glucans-triggered hydrogen peroxide production by murine peritoneal macrophages in vitro.

It has been reported that the biological activities of several beta-glucans vary due to differences in their physicochemical properties. In this study we investigated the ability of beta-glucans to trigger H2O2 production and activate signaling pathway on peritoneal macrophages. The most effective beta-glucan tested on H2O2 production was zymocel which was a particulate preparation from the yeast cell wall. In contrast, gel-forming beta-glucans which are known as immunoenhancers did not trigger the H2O2 production by macrophages at all. To identify the related signaling pathway for the particulate beta-glucans-triggered H2O2 production, several inhibitors were applied. Hydrogen peroxide production triggered with phorbol myristate acetate was inhibited by pretreatment of macrophages with H-7, a protein kinase C inhibitor. However, beta-glucans-triggered H2O2 production was not affected by H-7. The results suggested that genistein-sensitive tyrosine kinase and bromophenacyl bromide-sensitive phospholipase A2 participated in the particulate beta-glucans-triggered H2O2 production, although the phagocytosis of particulate beta-glucans was not inhibited by either reagents. In conclusion, gel-forming (1-->3)-beta-D-glucans-induced activation was not sufficient to trigger H2O2 on macrophages, and pathways for particulate beta-glucans-triggered H2O2 production were regulated differently from those for phagocytosis of beta-glucans.

Animals↗

PubMed1996

Cloning and characterization of mycovirus double-stranded RNA from the plant pathogenic fungus, Fusarium solani f. sp. robiniae.

A mycovirus (named FusoV) from the phytopathogenic fungus, Fusarium solani f. sp. robiniae SUF704, has two kinds of double-stranded (ds) RNA genomes, designated M1 and M2. The cDNAs were constructed from FusoV genomic dsRNAs. The sequences of M1 and M2 cDNAs comprised 1645 and 1445bp, respectively. Sequence analysis showed that each dsRNA had a single long open reading frame (ORF) on only one of the strands. M1 ORF encodes a 519-amino acid residue polypeptide with a predicted molecular mass of 60 kDa. RNA-dependent RNA polymerase-conserved motifs were identified in the predicted amino acid sequence, and the polymerase synthesized dsRNA in vitro. The M2 ORF encodes a polypeptide of 413 amino acid residues with a predicted molecular mass of 44 kDa. The predicted amino acid sequence contained the sequence corresponding to those found in the purified 44-kDa capsid protein of FusoV.

Amino Acid Sequence↗

PubMed1996

Influence of high dose inhaled steroids on hypothalamo-pituitary-adrenal axis function in Japanese patients with asthma: a comparison over the course of time.

Although the influence of high dose inhaled steroids on hypothalamo-pituitary-adrenal (HPA) function in patients with asthma has been extensively studied worldwide, there has been limited information on Japanese asthmatics, especially in terms of a prospective analysis of HPA function in the course of time. We analyzed the changes in HPA function using 2 serial short tetracosactrin tests (STT) separated by an interval of one year in 11 Japanese asthmatics who were treated with high dose inhaled steroids alone [beclomethasone dipropionate (BDP); mean dose 982 micrograms/day] during the period between 2 STTs. Mean values of plasma cortisol before administration of ACTH, maximum cortisol and the rise in cortisol in response to ACTH in the 2 STTs were 7.8, 20.5 and 12.7 micrograms/dl for the 1st test, and 8.9, 23.6 and 14.7 micrograms/dl for the 2nd test, respectively. Overall, there was no significant change in the course of time in each of these 3 values. Although the results of the 1st STT proved to be abnormal in 3 patients who had been receiving systemic steroids before their 1st STT, they improved uniformly in their 2nd STT. In the remaining 8 patients, who had never received systemic steroids, 4 patients showed improvements while the other 4 showed deterioration in HPA function in their serial STTs over the course of time. The dose of BDP was 800 micrograms/day in the former 4 patients, while it was 1,200 micrograms/day in the latter 4. Furthermore, only one patient, in whom BDP had been increased from 800 micrograms/day to 1,200 micrograms/day between the 2 tests, developed an abnormal response in the 2nd STT. On the other hand, one patient whose BDP dose was increased from 800 micrograms/day to 1,600 micrograms/day showed an improvement in HPA function in the 2nd test. These results indicate that the threshold dose of BDP which may cause HPA suppression in Japanese asthmatics lies between 800-1,200 micrograms/day, although there is a large inter-individual variation in terms of such doses.

Administration, Inhalation↗

PubMed1996

Hepatitis B virus carrier status linked to autoimmune hepatitis.

We describe a hepatitis B virus carrier who satisfied the criteria of autoimmune hepatitis proposed by the International Autoimmune Hepatitis Group. A 43-year-old Japanese female showed human leukocyte antigen typing including DR4 in addition to hypergammaglobulinemia, presence of autoantibodies, and liver histology suggestive of autoimmune hepatitis. Moreover, the predominant presence of hepatitis B core antigen in nuclei rather than in cytoplasm of hepatocytes suggested less of a possibility of liver cell damage related to hepatitis B virus infection. She completely responded to immunosuppressive therapy and no clinical or biochemical relapse has been recognized to date.

Adult↗

PubMed1996

Recombinant human growth/differentiation factor 5 stimulates mesenchyme aggregation and chondrogenesis responsible for the skeletal development of limbs.

We have expressed and biologically characterized recombinant human growth/differentiation factor 5 (huGDF5). This protein is composed of a mature homodimer consisting of 15 kD subunits. Using recombinant expressed protein, we have demonstrated that huGDF5 in vitro stimulated mesenchyme aggregation and chondrogenesis in rat limb bud cells. In vivo, partially purified huGDF5 induced cartilage and bone formation in muscular tissues of rodents. However, in contrast to the effects of other BMPs, as for example BMP-2, the osteoblastic MC3T3-E1 cells did not respond to huGDF5 as measured by alkaline phosphatase activity. These results suggest that the action of GDF5 may be relatively specific for chondrogenesis during the entire process of the endochondral bone formation. GDF5 may control the morphogenesis of cartilaginous tissue, including joints, in the skeletal development of limbs.

Alkaline Phosphatase↗

PubMed1996

[Progress of ductoscopy of the breast].

Ductoscopy of the breast was initially performed utilizing a rigid scope. Improvements in endoscopic equipment and introduction of the silica-fiberscope have enabled observation of intraductal lesions. The silica-fiberscope can be gradually moved into peripheral sites, after which the endoscopic findings are compared with histological features and diagnostic imaging. The most common symptom dictating endoscopic examination is a discharge from the nipple in which no palpable mass is detected. The fiberscope is introduced through the duct orifice on the surface of the nipple. The characteristic feature of a cancerous lesion is a superficial spread along the surface of the ductal lumen, which differs from the typical features of intraductal papilloma. Microsampling methods such as tube curette cytology should be used to obtain a definitive diagnosis. Endoscopic examination can provide valuable information which will be helpful in the decision process such as; surgical methods, nipple-preservation, and breast conservation.

Breast↗

PubMed1996

[A quantitative analysis of the cells infected with Epstein-Barr virus in the peripheral blood mononuclear cells derived from the patients with infectious mononucleosis].

The quantitative analysis of the cells infected with Epstein-Barr virus was performed on the peripheral blood mononuclear cells from the patients with infectious mononucleosis, by using in situ hybridization with Epstein-Barr virus encoded small nuclear RNA1 (EBER1). An alkaline-phosphatase conjugated oligonucleotide probe complementary to EBER1 was used as an antisense probe, while oligonucleotide DNA probe compatible with the sequence of EBER1 was used as a sense probe, control probe. The EBER1 positive cells on the slide-glass were enumerated microscopically. In situ hybridization revealed that 50,000 peripheral blood mononuclear cells from the patients in the acute phase of infectious mononucleosis contained 35 +/- 36 cells infected with Epstein-Barr virus (n = 11). The cells infected with Epstein-Barr virus apparently decreased in the convalescence of all the patients with infectious mononucleosis and the mean of the cells infected with Epstein-Barr virus was 3 +/- 4 in the convalescence (n = 6) (p < 0.02). On the other hand, no positive cells were detected in healthy individuals with past-infection of Epstein-Barr virus (n = 10) or without any previous Epstein-Barr virus infection (n = 11). The striking increase of the cells with Epstein-Barr virus genome was clearly demonstrated in the peripheral blood mononuclear cells from the patients with infectious mononucleosis.

Child↗

PubMed1996

[Computed tomographic findings in septic pulmonary emboli secondary to renal abscess].

A 73-year-old woman with diabetes mellitus and hypothyroidism had been well until 4 days before she presented with fever, productive coughing, and general malaise. Dyspnea gradually worsened, and she was admitted to Kobe City General Hospital. She appeared toxic and was in moderate respiratory distress on admission. There were scattered rales in both lung fields. The abdomen was soft with no tenderness. A chest roentgenogram showed peripheral infiltrates in both lung fields. Arterial blood gas analysis showed a Po2 of 48.6 Torr and Pco2 of 27.2 Torr. A blood culture on admission showed Escherichia coli. Computerized tomography of the chest showed multiple nodules of various sizes in the peripheral lung fields. Some nodules had necrotic centers and feeding vessels. Wedge-shaped lesions abutting the pleura were also seen. These findings strongly suggested septic pulmonary emboli. An abscess in the left kidney, which was considered to be the source of the septic pulmonary emboli, was found with Ga scintigraphy, ultrasonography, and computerized tomography of the abdomen. Treatment with antibacterial drugs was effective against the lung lesions but not the renal abscess. A left nephrectomy was done. In the proper clinical setting, characteristic CT features of septic emboli can contribute to early diagnosis of this disease.

Abscess↗

PubMed1996

Alpha 1 adrenergic receptor activation of proto-oncogene expression in arterial smooth muscle: regulation by nitric oxide and vascular injury.

The role of the endothelium in modulating smooth muscle cell growth is unclear. alpha 1 adrenergic receptors activate proto-oncogene expression in smooth muscle. We have now found in rat aorta that carbachol, a muscarinic cholinergic agonist that promotes release of nitric oxide (NO), inhibits expression of c-fos and c-jun mRNA induced by alpha 1 receptors. NO synthase inhibitors blocked the effects of carbachol on c-fos mRNA and a cGMP analog mimicked carbachol. After balloon injury in rat aorta using in situ hybridization, the catecholamine-induced increase in c-fos mRNA expression in the medial layer was inhibited by the alpha 1 receptor antagonists, prazosin and chloroethylclonidine. In the neointima, this response was fully blocked by prazosin; however, chloroethylclonidine only partially inhibited it. These results suggest that NO, acting through a cGMP-dependent mechanism, inhibits expression of the c-fos and c-jun genes in arteries, which may contribute to the growth-inhibiting effects of the endothelium. After endothelial damage, the activation of c-fos in neointima by adrenergic stimulation may involve a subtype of alpha 1 receptor different from that utilized in medial smooth muscle.

Animals↗