Biomedical subjects

H Fujii

Publications and source records attributed to H Fujii.

At least 757 records · Page 42Linked to original sources

PubMed1990

Studies on the superoxide releasing site in plasma membranes of neutrophils with ESR spin-labels.

Superoxide (O2-)-generating membranes of pig blood neutrophils were studied by the ESR spin-label method. Neutrophils were spin-labeled with doxylstearic acids, consisting of nitroxide free radicals bonded to the 5, 7, 12, or 16 position of stearic acid (5-, 7-, 12-, or 16-DS), to detect the reduction of their nitroxide radicals at different positions in the membrane. The spin-labeled cells were then stimulated with phorbol myristate acetate (PMA). Stimulation of the labeled cells resulted in a marked decrease in the spin concentration of 5-DS due to the reduction by O2-, but not in those of the other three DS labels. This reduction of 5-DS was completely inhibited by copper salicylate (CS), a hydrophobic and permeable O2(-)-scavenger, but not by superoxide dismutase (SOD). CS was not inhibitory on the respiratory burst, i.e., O2(-)-generating activity of neutrophils. On the contrary, if the spin-labels were present in the extracellular medium, SOD inhibited the reduction of all four DS labels due to O2- released from PMA-stimulated cells. These results suggest that the O2(-)-releasing site is not located at the outer surface of the plasma membrane but in an inner hydrophobic environment a short distance (around 4-5 A) from its outer surface.

Animals↗

PubMed1990

Direct measurement of superoxide anion produced in biological systems by ESR spectrometry: a pH-jump method.

For direct measurement of the ESR signal of superoxide anion (O2-) produced in biological samples, O2- generated at a physiological pH was trapped in alkaline media instead of by a rapid freezing method, and then its signal was measured by ESR spectroscopy at 77 K. A reaction mixture for O2- generation, such as xanthine oxidase-xanthine and neutrophils, was incubated at a physiological pH (pH 7.0-7.5) for a suitable reaction period (30s), then an aliquot (300 microliters) was pipetted out and squirted into 600 microliters of 0.5 M NaOH to stabilize O2- (pH-jump). The alkaline mixture was promptly introduced into an ESR tube and frozen by dipping the tube directly into a cooling liquid. A typical signal of O2- was detected by ESR spectroscopy and the amount of trapped O2- was measured quantitatively at 77 K. The back reaction of O2- generation from H2O2 was negligible in 0.5 M NaOH. To avoid any artificial spectrum due to autoxidation of biological samples by the pH-jump procedure, the background spectrum should be subtracted from the obtained spectrum. This pH-jump method should be widely available for direct demonstration of O2- production in biological systems at physiological pH, because an advantage of this method is the simple operation for trapping O2- without the use of any rapid-mixing apparatus as compared with the rapid freezing method.

Animals↗

PubMed1990

Development of serum Dermatophagoides farinae-, ovalbumin- and lactalbumin-specific IgG, IgG1, IgG4, IgA and IgM in children with bronchial asthma/allergic rhinitis or atopic dermatitis.

Dermatophagoides farinae-, ovalbumin- and lactalbumin-specific IgG, IgG1, IgG4, IgA and IgM were evaluated in 161 healthy children [Group 1], 84 children with bronchial asthma and/or allergic rhinitis but without atopic dermatitis [Group 2], and 54 children with atopic dermatitis but without bronchial asthma and allergic rhinitis [Group 3]. We also studied D. farinae-, egg-white-, and milk-specific IgE of children with allergic diseases. D. farinae-specific IgG, IgG1, IgG4 and IgA in Groups 2 and 3 increased until 5 years of age and thereafter they remained constant. After 2 years of age, D. farinae-specific IgG, IgG1, IgG4 and IgA in Group 2 were higher than those in Groups 1 and 3. Ovalbumin- and lactalbumin-specific IgG, IgG1, IgG4 and IgA in Groups 2 and 3 increased until 1 year of age and thereafter decreased. Until 1 year of age, ovalbumin- and lactalbumin-specific IgG, IgG1 and IgG4 in Groups 3 were higher than those in Groups 1 and 2. D. farinae-, ovalbumin- and lactalbumin-specific IgM were constant in all ages of all groups. These results suggest that atopic dermatitis in young children is related to food-specific immunoglobulins and that respiratory allergic diseases in older children is related to D. farinae-specific immunoglobulins.

Adolescent↗

PubMed1990

The prevalence of sensitivity to constituents of dental alloys.

Ninety-five participants were epicutaneous patch tested in order to determine the prevalence of sensitivity to components of dental alloys. Seventeen individuals (17.9%) developed allergic reactions, which were caused by mercury (10.5%), copper (2.1%), nickel, cobalt, tin, gold and zinc (1.1%). Eight of 17 allergic responders had a history of dermatitis from metal contact. The results show that there is a need for careful immunological considerations during the selection of suitable alloys, particularly in the case of patients with lesions suspected of being caused by dental alloys.

Adult↗

PubMed1990

The temporomandibular joint in rheumatoid arthritis--a comparative clinical and tomographic study pre- and post-prosthesis.

Six partially or fully edentulous rheumatoid patients participated in the study. By comparing the clinical symptoms and tomograms of the temporomandibular joints (TMJS) pre-prosthesis with those post-prosthesis, this report assesses whether dental treatment could provide positive help for TMJS in patients with rheumatoid arthritis (RA). Among the clinical symptoms of TMJ dysfunction, pain from the TMJ region and limitations of movement were improved in all the patients post-prosthesis. Tomographic evidence of desirable remodelling of the condylar heads was observed in two cases.

Adult↗

PubMed1990

A histopathological study on senile changes in the human olfactory bulb.

Senile changes in the human olfactory bulb were studied histopathologically in 133 individuals ranging in age from 40 to 91 years with a mean age of 64.3 years. Neurofibrillary tangles (NFTs) in the olfactory bulb were observed in 47 subjects aged over 50 years. The frequency of NFTs was 35.3% (47/133) in total and 40.5% (47/116) among subjects 50 years of age or older. The frequency of individuals with NFTs increased linearly with age. Senile plaques (SPs) were observed in 5 individuals over 60 years old at a frequency of 3.8% (5/133) in total and 5.7% (5/88) among individuals 60 years old or more. Granulovacuolar degeneration was rarely seen, and amyloid angiopathy was not recognized. Senile changes in the hippocampus and parahippocampal gyrus were also examined. In some cases, the frequencies of NFTs and SPs in the hippocampal region were not identical to those in the olfactory bulb. However, it was not apparent whether senile changes first appear in the olfactory bulb or in the hippocampal region.

Adult↗

PubMed1990

Anaplastic ependymoma of the spinal cord in childhood. A case report.

We report a 6-year-old girl with anaplastic ependymoma probably originating in the region of the conus medullaris and probably spreading retrogradely to the region of the interventricular foramen (Monro) through the cerebrospinal fluid (CSF). Since ependymoma of the spinal cord rarely occurs in children, and retrograde spreading is extremely rare, the histological features and mechanism of metastasis of the tumor are discussed.

Child↗

PubMed1990

Activation of octamer-containing promoters by either octamer-binding transcription factor 1 (OTF-1) or OTF-2 and requirement of an additional B-cell-specific component for optimal transcription of immunoglobulin promoters.

Several distinct octamer-binding transcription factors (OTFs) interact with the sequence ATTTGCAT (the octamer motif), which acts as a transcription regulatory element for a variety of differentially controlled genes. The ubiquitous OTF-1 plays a role in expression of the cell cycle-regulated histone H2b gene as well as several other genes, while the tissue-specific OTF-2 has been implicated in the tissue-specific expression of immunoglobulin genes. In an attempt to understand the apparent transcriptional selectivity of these factors, we have investigated the physical and functional characteristics of OTF-1 purified from HeLa cells and both OTF-1 and OTF-2 purified from B cells. High-resolution footprinting and mobility shift-competition assays indicated that these factors were virtually indistinguishable in binding affinities and DNA-protein contacts on either the H2b or an immunoglobulin light-chain (kappa) promoter. In addition, each of the purified factors showed an equivalent intrinsic capacity to activate transcription from either immunoglobulin promoters (kappa and heavy chain) or the H2b promoter in OTF-depleted HeLa and B-cell extracts. However, with OTF-depleted HeLa extracts, neither factor could restore immunoglobulin gene transcription to the relatively high level observed in unfractionated B-cell extracts. Restoration of full immunoglobulin gene activity appears to require an additional B-cell regulatory component which interacts with the OTFs. The additional B-cell factor could act either by facilitating interaction of OTF activation domains with components of the general transcriptional machinery or by contributing a novel activation domain.

Base Sequence↗

PubMed1990

Fine epitope mapping of the human SS-B/La protein. Identification of a distinct autoepitope homologous to a viral gag polyprotein.

To analyze the autoepitopes on the SS-B/La protein, a cDNA covering the entire region coding the protein was isolated from a human cDNA library. The cDNA was subcloned into an expression plasmid vector, pEX, to express its protein product as a fusion protein with cro-beta-galactosidase in Escherichia coli. A recombinant pEX plasmid expressing three-fourths of the protein (amino acid 112-408) was also constructed. The antigenicities of these recombinant proteins were confirmed with a patient's serum. Their various deletion mutants were produced with exonuclease III treatment from the 3' ends of the cDNAs without changing the proper translational frame. Immunoblot analysis and enzyme-linked immunosorbent assay were used to evaluate the reactivities of the recombinant proteins with patients' sera to determine the autoepitopes. A narrow segment (amino acid 88-101) and the region where several epitopes were located (amino acid 283-338) on the SS-B/La protein were universally recognized by all the sera with anti-SS-B/La antibodies examined. An additional epitope region (amino acid 179-220) was recognized by some patients' sera. Computer analysis revealed that the most distinct autoepitope, amino acid 88-101, had a striking homology to a retroviral gag polyprotein. These findings indicate that exogenous or endogenous retroviruses may play a role in initiation of the anti-SS-B/La autoimmunity.

Amino Acid Sequence↗

PubMed1990

Inhibitory effect of somatomedin C/insulin-like growth factor I on adrenocorticotropin- or forskolin-induced steroidogenesis in isolated rat adrenocortical cells.

The effects of recombinant human somatomedin C/insulin-like growth factor (IGF-I) on the steroidogenic response of isolated rat adrenocortical cells to ACTH, forskolin, and (Bu)2cAMP were examined during short term incubations. The effect of IGF-I on cAMP production by cells stimulated with ACTH or forskolin was also examined. IGF-I inhibited ACTH-, forskolin-, and (Bu)2cAMP-induced corticosterone production in a concentration-dependent manner. IGF-I (30 ng/ml) also significantly inhibited ACTH-induced cAMP production. However, the peptide had no significant effect on forskolin-induced cAMP production. IGF-I suppressed ACTH-induced cAMP production both in the presence and absence of 3-isobutyl-1-methylxanthine, suggesting that IGF-I acts to inhibit the formation of cAMP rather than the stimulation of cAMP degradation. The observation that IGF-I inhibited steroidogenesis induced by (Bu)2cAMP strongly suggests that one site of inhibition is at some step(s) distal to cAMP formation. However, the inhibition of cAMP production after stimulation with ACTH also suggests a plasma membrane site of action for IGF-I in adrenocortical cells.

Adrenal Cortex↗

PubMed1990

A patient with hypocortisolism and Cushing's syndrome-like manifestations: cortisol hyperreactive syndrome.

One patient is reported who has the manifestations of Cushing's syndrome in spite of persistent hypocortisolemia. His serum levels of cortisol and free cortisol were below normal, and 24-h urinary excretion of 17-hydroxycorticosteroids and cortisol were decreased. There was a rapid and substantial increase in serum cortisol in response to synthetic ACTH-(1-24). Plasma levels of ACTH were marginally increased by successive administration of CRH and vasopressin, which were followed by substantial increases in serum cortisol. Glucocorticoid activity of the patient's serum, as measured by a RRA was low. There were no responses of urinary 17-hydroxycorticosteroids after metyrapone treatment. These laboratory examinations ruled out any known clinical conditions resulting in hypocortisolemia. The clinical condition could also be explained by cortisol hyperreactivity of the patient's cells. In vitro hyperreactivity to glucocorticoids was demonstrated in cultured skin fibroblasts whose aromatase activity was increased 1.5- to 1.8-fold above that of normal cells, and [3H]thymidine incorporation was inhibited more effectively by the addition of cortisol or dexamethasone. The mechanism by which the patient is hyperreactive to glucocorticoids remains unexplained.

Adrenocorticotropic Hormone↗

PubMed1990

The effect of ionizing radiation on epidermal Langerhans cells--a quantitative analysis of autopsy cases with radiation therapy.

Langerhans cells (LCs) are dendritic cells located in the epiderm is with antigen-presenting capacities. We performed a quantitative analysis of LC density in the anterior chest skin of 286 autopsy cases, including 31 cases treated with radiation therapy. Skin specimens were stained by immunoperoxidase technique (PAP method) with an anti-S-100 protein antiserum. S-100 positive LCs were counted for comparison between non-irradiated and irradiated cases. In this study we noted that, 1) The decline in density of the LCs was age-related and dendritic processes were more prominent in younger groups. 2) The cases irradiated within one month before autopsy showed a reduction in LC density compared with age-matched controls. 3) The cases irradiated more than one month before autopsy demonstrated no consistent or definite tendency. It is suggested that ionizing irradiation as well as ultraviolet light may deplete the LC density in an acute phase. The possibility that radiation therapy alters immunological surveillance in the human skin is discussed.

Adolescent↗

PubMed1990

Complementary DNA sequence of 3-methylcholanthrene-inducible P-450 from the rat lung.

Cytochrome P-450MC was induced in pulmonary microsomes of 3-methylcholanthrene-treated rats and also at low level in that of isosafrole-treated rats. Cytochrome P-450d was not detected in the lungs of 3-methylcholanthrene- or isosafrole-treated rats by the method of Western blot analysis with a polyclonal antibody raised against cytochrome P-450c which is equally effective against P-450d, nor by the method of Northern hybridization probed with pcP450mc3 (P-450d probe). Complementary DNA of P-450MC was isolated from rat pulmonary cDNA library and the nucleotide sequence of pulmonary cDNA was compared with that of hepatic P-450c cDNA reported by Yabusaki et al. There was no gross change in nucleotide sequences of cDNA between pulmonary P-450MC and hepatic P-450c.

Amino Acid Sequence↗

PubMed1990

A new approach for identification of rat lymphatic capillaries using a monoclonal antibody.

In order to discriminate rat lymphatics from blood vessels on tissue cryosections by immunohistochemistry, a mouse monoclonal antibody (B27) was produced by immunization of mice with a homogenate of rat thoracic duct. B27 strongly recognized endothelial cells of almost all rat lymphatics, such as lacteals, lymphatic capillaries in the diaphragm at sites of absorption from the peritoneal cavity, collecting lymphatics and the thoracic duct. Besides the lymphatics, B27 reacted with the endothelium of some types of blood vessel, the mesothelium of the peritoneal cavity and substances between smooth muscle fibers. A new double immunostaining technique was then developed to distinguish the lymphatic capillaries, having no or only scanty basement membranes more clearly from the blood vessels. Cryosections were stained first with an anti-type IV collagen antibody for basement membranes, secondly with B27 for the endothelium, and then examined by either light microscopy or fluorescence microscopy. With this technique, the lymphatic capillaries were easily distinguished from other vessels by their positive reaction with B27 alone. B27 appears to be very useful for the simple and reliable identification of rat lymphatics, particularly lymphatic capillaries, in various tissues when applied for double immunostaining.

Animals↗

PubMed1990

[Ultrasonographic study on kidneys in patients with chronic renal failure. Part I. Ultrasonic measurement of renal size and analysis of renal ultrasonotomograms].

Ultrasonograms of 546 kidneys were obtained in 280 patients undergoing chronic dialysis. Dialysed kidneys could be detected in 529 of the 546 kidneys (96.9%) by ultrasonic examination. The ultrasonic diagnoses on dialysed kidneys were contracted kidney in 313 kidneys (59.2%) and acquired cystic disease of the kidney in 107 kidneys (20.2%). Ultrasonic measurement of the size of kidney (length and thickness) revealed that the kidneys in patients with chronic renal failure were much smaller than normal ones. But the kidneys in patients undergoing dialysis for more than 8 years gradually increased in size with incidence of acquired renal cysts. The kidneys in patients with diabetic nephropathy were greater in length and thickness than those with chronic glomerulonephritis. Sonographic features of dialysed kidneys were unclear renal imaging, unidentified central echoes, cortico-medulla + border and increased parenchymal echogenicity. Irregularity of the renal contour had a tendency to increase in number with incidence of cysts in long-term dialysis patients. The ultrasonograms of the kidneys with diabetic nephropathy showed fewer changes than normal ones. No major complication of the kidney was detected in the present study. However, two retroperitoneal hematomas and one renal cell carcinoma developed within two years after this examination. We believe that regular screening of the kidneys by ultrasonic examination is mandatory in patients on chronic dialysis for early diagnosis and treatment of these complications.

Adolescent↗

PubMed1990

[Ultrasonographic study on kidneys in patients with chronic renal failure. Part II. Acquired cystic disease of the kidneys].

Ultrasonic examination of the kidney was performed on 280 patients undergoing chronic dialysis. Acquired cystic disease of the kidney (ACDK) was detected in 107 of 529 kidneys (20.2%). This paper presents an analysis of ultrasonotomograms of ACDK. Ultrasonic measurement of the size of ACDK was 72.5 +/- 15.2 mm in length and 41.7 +/- 9.8 mm in thickness. The size of ACDK was significantly greater than that of contracted kidneys by ultrasonographic diagnosis. With regard to sex distinction the length and thickness of ACDK were significantly greater in males than in females. As for laboratory data, patients with ACDK showed significantly higher values of red blood cell count, hematocrit and serum creatinine concentration compared with contracted kidneys. Prolongation of the dialysis peirod increased the incidence of ACDK. The size of ACDK showed a tendency to increase with duration of dialysis. However, no correlation was noted statistically between the incidence of ACDK and duration of dialysis and between the size of ACDK and duration of dialysis. There was a significantly lower incidence of ACDK in patients with diabetic nephropathy than those with chronic glomerulonephritis. A sonographic feature of ACDK is irregularity of the renal contour because of cystic transformation. Renal imaging, identification of the corticomedullary border, identification of the central echoes and increased parenchymal echogenicity were similar to other dialyzed kidneys. The main complications of ACDK are hemorrhage and tumor formation. We observed two retroperitoneal hematomas and one renal cell carcinoma developed within two years after this examination. The incidence of complications of ACDK was 5.1 per cent. We believe that patients with ACDK should be watched carefully by regular ultrasonic examination for early diagnosis and treatment of these complications.

Adult↗

PubMed1990

Deoxyspergualin directly suppresses antibody formation in vivo and in vitro.

The effect of deoxyspergualin (DSG, NKT-01) on humoral immunity was investigated both in vitro and in vivo. DSG inhibited the primary and secondary responses to T cell-dependent antigens and the response to T cell-independent antigens in thymic and athymic mice. However, natural antibodies in non-sensitized mice were affected less by the administration of DSG. The agent produced a dose-dependent inhibition of B cell proliferation and antibody production to lipopolysaccharide in vitro. Suppression of secondary antibody response was also shown, whenever antigen stimulation was not given, antibody production was not affected. These results suggest that DSG affects the proliferative stage of B lymphocytes in such a way as to inhibit their growth and antibody production.

Animals↗

PubMed1990

[A myeloma (IgG-kappa) terminating in acute myelogenous leukemia].

A 71-year-old man was hospitalized in November, 1983 for a back pain and a diagnosis of multiple myeloma was made, based on the Bence Jones proteinuria, The serum M-component of a IgG-kappa type (3.3 g/dl), and plasmacytosis in the bone marrow (37%). Treatment consisted of melphalan and prednisolone. A blood count in March, 1986 revealed 6000/microliters of WBC with 30% of a blast form and 8% plasma cells, and 20,000/microliters of platelets. A bone marrow aspirate revealed that 14% were myeloblasts and 26% were plasma cells. Distinguishing the myeloblasts from the immature plasma cells in the peripheral blood proved difficult. Studies by electron microscopy and an immunological inspection of phenotypes were helpful in achieving a determination. A karyotypic analysis of the bone marrow cells indicated a hypodiploid cell population, a marker chromosome, and a karyotypic instability. These findings indicate that his multiple myeloma had undergone a leukemic change associated with acute myelogenous leukemia.

Aged↗