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Biomedical subjects

A Saitoh

Publications and source records attributed to A Saitoh.

At least 91 records · Page 5Linked to original sources
PubMed1994

Detection of glycosylated protein in glomeruli of STZ-induced diabetic rats using the nitroblue tetrazolium (NBT) reaction.

Detection of glycosylated protein in renal tissues was determined in streptozotocin (STZ)-induced diabetic rats using the nitroblue tetrazolium (NBT) reaction. The glycosylation of extra-cellular matrix (ECM) components such as laminin and fibronectin was examined in vitro using the same method. Immunofluorescence staining of laminin or type IV collagen was also performed in renal tissues of STZ-induced diabetic rats. There was no significant difference in the intensity of NBT in renal tissues between 4 week STZ-induced diabetic rats and control rats of the same age. The intensity of NBT staining in the glomerular mesangial areas and capillary walls was marked in 12 week diabetic rats. The mean values of fructosamine measured by the NBT reaction in the glycosylated-laminin and fibronectin were increased dose dependently. In immunofluorescence, laminin and type IV collagen were observed significantly in the glomerular mesangial areas and capillary walls of 12 week diabetic rats. However, there was no significant change in renal histopathology in 4 and 12 weeks diabetic rats. It appears that the non-enzymatic glycosylation and expression of ECM components in glomeruli increased in the early stage of diabetic nephropathy prior to the appearance of marked histologic alterations. In conclusion, non-enzymatic glycosylation of glomerular structural components may play an important role in the initiation of the early stage of renal injuries in diabetes.

Animals↗
PubMed1994

Diagnosis of HIV-1 infection by detection of antibody IgG to HIV-1 in urine with ultrasensitive enzyme immunoassay (immune complex transfer enzyme immunoassay) using recombinant proteins as antigens.

Anti-HIV-1 IgG in urine was detected by an ultrasensitive enzyme immunoassay (immune complex transfer enzyme immunoassay) using recombinant reverse transcriptase (RT), p17 and p24 as antigens, and beta-D-galactosidase from Escherichia coli as label. Anti-HIV-1 IgG in urine was reacted simultaneously with 2,4-dinitrophenyl-bovine serum albumin-recombinant protein conjugate and recombinant protein-beta-D-galactosidase conjugate. The immune complex formed, consisting of the three components, was trapped onto polystyrene balls coated with affinity-purified (anti-2,4-dinitrophenyl group) IgG. After washing, the immune complex was eluted from the polystyrene balls with excess of epsilon N-2,4-dinitrophenyl-L-lysine and transferred to clean polystyrene balls coated with affinity-purified (anti-human IgG gamma-chain) IgG. Finally, the enzyme activity bound to the last solid phase was assayed by fluorometry. Using recombinant RT as antigen, the sensitivity and specificity for 83 seropositives and 100 seronegatives were both 100%, and the lowest signal for 60 asymptomatic carriers was 8.2-fold higher than the highest signal for the seronegatives. The positivity with recombinant RT as antigen could be confirmed by using recombinant p17 and p24 as antigens. The sensitivity could be improved by a longer assay of bound beta-D-galactosidase activity by using concentrated urine samples and by the combined use of recombinant RT, p17, and p24. Thus, reliable diagnosis of HIV-1 infection was possible for asymptomatic carriers.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Gastrospirillum hominis-associated gastritis: the first reported case in Japan.

Tightly coiled spiral micro-organisms (Gastrospirillum hominis), distinct from Helicobacter pylori, were found in the gastric mucosa of a 66-year-old man with a 4-month history of intermittent epigastric pain. The organisms were distributed in the antral mucosa, which showed erosive gastritis; histologically, the affected mucosa presented moderate to severe chronic gastritis with focal neutrophil infiltration. After a 2-week administration of cimetidine, his symptoms resolved and the active inflammation was reduced, both endoscopically and histologically, but the organisms still remained. Biopsy specimens taken 4 weeks after treatment with minocycline and cimetidine showed normal gastric mucosa without the spiral organisms. The above clinical course suggests the possible role of Gastrospirillum hominis in the pathogenesis of gastritis.

Aged↗
PubMed1994

Migration of Thy-1+ dendritic epidermal cells (Thy-1+DEC): Ly48 and TNF-alpha are responsible for the migration of Thy-1+DEC to the epidermis.

Thy-1+ dendritic epidermal cells (Thy-1+DEC) are mainly T cells that express T-cell receptor gamma and delta chains with limited diversity of gamma delta, mainly gamma 3 delta 1; such gamma 3 delta 1 TCR-bearing Thy-1+DEC originate from day 16 fetal thymic cells. To understand the migratory capability of Thy-1+DEC, we developed an in vitro model, using skin organ culture. First, emigration of Thy-1+DEC from the epidermis was examined. Ear skin from C3H/He mice was separated into two parts and incubated for 3 d with dermal side down. Thy-1+DEC emigrated from the epidermis into the dermis and then migrated out of the skin into the culture medium. Next, immigration of Thy-1+DEC into the epidermis was examined. Thy-1+DEC were depleted in vivo by daily application of clobetazole propionate solution topically onto the ears of C3H/He mice. Seven days later, ear skin was harvested, separated, and cultured with the dermal side up with syngeneic epidermal cell suspensions with a migration chamber for 3 d. It was found that 1) Thy-1+DEC immigrated into the Thy-1+DEC depleted epidermis as well as into untreated epidermis, and 2) the migratory capability of Thy-1+DEC was directly proved by a biolabeling technique with PKH-26. Blocking studies with various antibodies revealed that leukosialin (S11 monoclonal antibodies) and TNF alpha were important for Thy-1+DEC migration. Thus, Thy-1+DEC retain the potential for migration in vitro, and leukosialin and TNF alpha are partially responsible for the migration of Thy-1+DEC into the epidermis.

Animals↗
PubMed1994

Interferon-gamma-induced HLA-DR, but not ICAM-1, expression of human keratinocytes is down-regulated by calmodulin antagonist.

Interferon-gamma (IFN-gamma) has been shown to induce or enhance the expression of MHC class II and intercellular adhesion molecule-1 (ICAM-1) in a variety of human and murine cell types, including epidermal keratinocytes (KC). However, the expression of MHC class II and ICAM-1 molecules induced by IFN-gamma is not necessarily coordinated. We investigated the inhibitory effects of the calmodulin antagonist, W-7, and its chlorine deficient inactive analogue, W-5, on the expression of MHC class II (HLA-DR) and ICAM-1 by human KC incubated with IFN-gamma. We found that the IFN-gamma-induced expression of HLA-DR was reproducibly and dose-dependently inhibited by W-7. However, the expression of ICAM-1 was highly resistant to the inhibitory effects of W-7. Neither HLA-DR nor ICAM-1 expression was affected by W-5. These data suggest that the IFN-gamma-induced HLA-DR, but not ICAM-1, expression is mediated, if not exclusively, by calmodulin in human KC.

Calmodulin↗
PubMed1994

The role of S-mephenytoin 4'-hydroxylase in imipramine metabolism by human liver microsomes: a two-enzyme kinetic analysis of N-demethylation and 2-hydroxylation.

1. The metabolism of imipramine (N-demethylation and 2-hydroxylation) was studied in relation to the activity of S-mephenytoin 4'-hydroxylase in human liver microsomes. 2. Eadie-Hofstee plots for the formation of despiramine and 2-hydroxyimipramine were biphasic, suggesting that at least two enzymes are involved in both the N-demethylation and 2-hydroxylation of imipramine by human liver microsomes. 3. The respective mean (+/- s.d.) kinetic parameters for the N-demethylation and 2-hydroxylation of imipramine derived from a two-enzyme kinetic analysis were: Km1 = 1.1 +/- 0.4 and 1.6 +/- 0.6 microM, Vmax1 = 0.11 +/- 0.03 and 0.15 +/- 0.07 nmol mg-1 min-1, and Vmax1/Km1 = 0.10 +/- 0.02 and 0.09 +/- 0.04 ml mg-1 min-1; Km2 = 214 +/- 84 and 257 +/- 148 microM, Vmax2 = 2.22 +/- 0.69 and 0.53 +/- 0.15 nmol mg-1 min-1, and Vmax2/Km2 = 0.011 +/- 0.001 and 0.003 +/- 0.002 ml mg-1 min-1. 4. With regard to imipramine N-demethylation and 2-hydroxylation at 2 microM (representing high-affinity reactions) and at 400 microM (representing low-affinity reactions), only N-demethylation at 2 microM showed a close correlation with the 4'-hydroxylation of S-mephenytoin (rs = 0.952, P < 0.01; n = 10 livers). 5. Concentrations up to 250 microM S-mephenytoin inhibited the N-demethylation of imipramine (2 microM), but no further inhibition was observed using concentrations from 250 to 750 microM. 6. Imipramine inhibited S-mephenytoin 4'-hydroxylation competitively with a Ki value of 12.5 microM.(ABSTRACT TRUNCATED AT 250 WORDS)

Aryl Hydrocarbon Hydroxylases↗
PubMed1994

Detection of anti-human immunodeficiency virus type 1 (HIV-1) immunoglobulin G in urine by an ultrasensitive enzyme immunoassay (immune complex transfer enzyme immunoassay) with recombinant reverse transcriptase as an antigen.

Anti-human immunodeficiency virus type 1 immunoglobulin G in urine was detected by an immunoassay with reverse transcriptase as the antigen and beta-D-galactosidase as the label; this immunoassay was 30-fold more sensitive than the previous immunoassay with peroxidase as the label. The sensitivity and specificity were both 100%. The lowest signal for asymptomatic carriers was 20-fold higher than the highest signal for seronegative subjects.

Adolescent↗
PubMed1994

Detection of glycosylated protein in renal tissues and dermal vascular vessels in the microalbuminuric stage of diabetic nephropathy using the nitro blue tetrazolium reaction.

Detection of glycosylated protein in renal and dermal tissues was performed in patients in the microalbuminuric stage of diabetic nephropathy using the nitro blue tetrazolium (NBT) reaction. The intensity of NBT staining in glomeruli and dermal vascular vessels was marked in the microalbuminuric stage as well as in the overtly proteinuric stage. The NBT staining in the renal and dermal vascular walls in both stages was significantly stronger than in the samples of control autopsy patients. It appeared that nonenzymatic glycosylation in various tissues, i.e. kidneys and dermal vascular vessels, had already progressed in the microalbuminuric stage in patients with diabetic nephropathy.

Adult↗
PubMed1994

Brown papules and leukoderma in Darier's disease: clinical and histological features.

We report a Japanese case of Darier's disease with brown and white papules or maculae distributed on the neck, trunk and dorsa of hands. Both brown papules and leukoderma showed typical histological features of Darier's disease. Moreover, there were much fewer melanocytes and melanosomes in the epidermis of both lesions. The corneal layer of the brown papules was far thicker than that of the leukoderma. Therefore, the thick corneal layer of the brown papules may prolong the retention of a few melanosomes or a little melanin to induce hyperpigmentation, while the thin corneal layer of leukoderma may not do so, thereby producing hypopigmentation. The difference in clinical and histological courses after involvement of melanocytes was proposed to be the cause of the discrepancy between the previous reports. We conclude that leukoderma was the primary lesion, the postinflammatory depigmented spots, or the atypical or subclinical eruption of Darier's disease.

Adult↗
PubMed1994

A high-resolution line sensor-based photostereometric system for measuring jaw movements in 6 degrees of freedom.

Photostereometry has widely been applied to the measurement of mandibular movements in 6 degrees of freedom. In order to improve the accuracy of this measurement, we developed a system utilizing small LEDs mounted on the jaws in redundant numbers and a 5000 pixel linear charge-coupled device (CCD) as a photo-sensor. A total of eight LEDs are mounted on the jaws, in two sets of four, by means of connecting facebows, each weighing approximately 55 g. The position of the LEDs are detected in three-dimensions by two sets of three CCD cameras, located bilaterally. The position and orientation of the mandible are estimated from the positions of all LEDs measured in the sense of least-squares, thereby effectively reducing the measurement errors. The static overall accuracy at all tooth and condylar points was considered to lie within 0.19 and 0.34 mm, respectively, from various accuracy verification tests.

Biomedical Engineering↗
PubMed1994

Isolated paralysis of the infraspinatus muscle.

We report six patients with isolated paralysis of the infraspinatus and discuss the diagnosis, pathology, treatment, and outcome over a mean follow-up period of 33 months. Four patients were shown to have space-occupying lesions at the spinoglenoid notch by MRI or ultrasonography or both, and ganglia were confirmed and removed surgically in three, with good results. Ganglia at this site are not uncommon and should be included in the differential diagnosis of patients presenting with shoulder pain and weakness.

Adolescent↗
PubMed1994

[Neoadjuvant chemotherapy for elderly advanced gastric cancer: a case report of MTX/5-FU sequential therapy followed by radical gastrectomy].

A 70-year-old-male was diagnosed as having gastric cancer (Borr. 2, 78 mm in size on the body region; mod. dif. adenocarcinoma). CT scan revealed direct invasion of the liver. A course of MTX/5-FU sequential therapy was started (MTX 100 mg/m2, 5-FU 500 mg/m2, i.v., weekly; interval, 2 hours) on March 23, 1992. The gastric tumor showed 67% reduction on week 8 and 86% on week 10. The liver invasion had almost disappeared by CT scan (total doses, MTX 1,040 mg, 5-FU 6,750 mg). On June 25, the tumor was completely resected by radical.gastrectomy. The pathological specimen showed a "submucosal carcinoma" (10 mm in size, Stage I). Twenty-two months after the operation, the patient is alive and in good health. No cancer recurrence has been found without post-operative chemotherapy.

Adenocarcinoma↗
PubMed1994

[Infection in genitourinary cancer patients during cancer chemotherapy].

To examine the frequency and the type of infection during cancer chemotherapy in the urological field, we studied the causes of fever in 67 patients with genitourinary cancer. Twenty-six patients had developed a fever of higher than 38 degrees C. Although fever without proven infection was seen in 11 patients (42.3%), fever caused by pyelonephritis was the most common infection. There was a relationship between fever and the presence of hydronephrosis. Fever was observed more often in patients with a leucocyte count of less than 2,000 white blood cell/mm3. In conclusion, we recommend the interruption of cancer chemotherapy or the use of granulocyte colony-stimulating factor for the prevention of infection, when the leukocyte count is less than 2,000 cell/mm3, especially in patients with hydronephrosis.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1993

Detection of antibody IgG to HIV-1 in urine by sensitive enzyme immunoassay (immune complex transfer enzyme immunoassay) using recombinant proteins as antigens for diagnosis of HIV-1 infection.

For diagnosis of HIV-1 infection, attempts were made to detect anti-HIV-1 IgG in urine by sensitive enzyme immunoassay (immune complex transfer enzyme immunoassay) using recombinant reverse transcriptase (RT) and p17 as antigens. Anti-HIV-1 IgG in urine was reacted simultaneously with 2,4-dinitrophenyl-bovine serum albumin-recombinant protein conjugate and recombinant protein-enzyme conjugate. The enzymes used as labels were horseradish peroxidase for RT and Escherichia coli beta-D-galactosidase for p17. The complex formed, consisting of the three components, was trapped onto polystyrene balls coated with affinity-purified (anti-2,4-dinitrophenyl group) IgG, eluted with epsilon N-2,4-dinitrophenyl-L-lysine and transferred to polystyrene balls coated with affinity-purified (anti-human IgG gamma-chain) IgG. Finally, bound enzyme activity was assayed by fluorometry. Urine samples were collected from 100 seronegative subjects and 70 seropositive subjects. The sensitivity and specificity were both 100% with unconcentrated urine samples. The positivity was confirmed by preincubation of urine samples with excess of the antigens. The positivity and negativity with one of the two antigens could be confirmed with the other antigen. The positivity with low signals could be confirmed by concentration of urine samples. Detection of anti-HIV-1 IgG in urine by the immune complex transfer enzyme immunoassay using different antigens would make diagnosis of HIV-1 infection possible.

Adolescent↗
PubMed1993

Structural analysis on the sugar chains of human alpha 1-antitrypsin: presence of fucosylated biantennary glycan in hepatocellular carcinoma.

Chemical structures of the sugar chains of alpha 1-antitrypsin (AAT) from patients with hepatocellular carcinoma (HCC) and from healthy individuals with a different affinity for Lens culinaris agglutinin (LCA) were examined by pyridylamination of their oligosaccharides and stepwise exoglycosidase digestion in combination with reversed-phase and size-fractionation high-performance liquid chromatography. We found that the LCA-reactive species of AAT from patients with HCC carried both the biantennary sugar chain with a fucose residue at the innermost N-acetylglucosamine residue, Gal beta 1-4GlcNAc beta 1-2Man alpha 1-6(Gal beta 1-4GlcNAc beta 1-2Man alpha 1-3)Man beta 1-4GlcNAc beta 1-4(Fuc alpha 1-6)GlcNAc-PA, and the biantennary chain without a fucose residue, Gal beta 1-4GlcNAc beta 1-2Man alpha 1-6(Gal beta 1-4GlcNAc beta 1-2Man alpha 1-3)Man beta 1-4GlcNAc beta 1-4GlcNAc-PA, at a ratio of about 1:0.6. The LCA-nonreactive species of AAT contained the biantennary sugar chain Gal beta 1-4GlcNAc beta 1-2Man alpha 1-6(Gal beta 1-4GlcNAc beta 1-2Man alpha 1-3)Man beta 1-4GlcNAc beta 1-4GlcNAc as a major component. These results indicate that a characteristic feature of the carbohydrate chains of AAT from patients with HCC is an increment in fucosylation.

Carbohydrate Metabolism↗