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Biomedical subjects

S Kamiya

Publications and source records attributed to S Kamiya.

At least 91 records · Page 5Linked to original sources
PubMed1996

Immunocytochemical localization of 60-kDa heat shock protein in Vibrio cholerae.

The immunocytochemical localization of the 60-kDa heat shock protein (HSP) in Vibrio cholerae strain 569B was studied by transmission electron microscopy using a combination with the antigen-specific monoclonal antibody (5C3) and immunogold labelling. The labelling with gold particles in V. cholerae detected 2 types; the gold particles were exclusively detected in the cytoplasm for one type and in the periplasmic space for another type, suggesting that the 60-kDa HSP of V. cholerae corresponding immunologically to Escherichia coli GroEL may translocate from the cytoplasm to the periplasmic space in the V. cholerae cell.

Animals↗
PubMed1996

Flow cytometric analysis of the heat shock protein 60 expressed on the cell surface of Helicobacter pylori.

The expression of a 60-kDa heat shock protein (HSP60) on the cell surface of Helicobacter pylori was analysed by flow cytometry with polyclonal antibody directed to HSP60. All 13 strains of H. pylori examined expressed HSP60 on the cell surface, although the intensity of expression was different among the strains and depended on culture conditions. There was a correlation between the intensity of HSP60 expressed on the cell surface and the rate of adherence to human gastric carcinoma cells (MKN45) by H. pylori, but not with urease activity and production of vacuolating toxin. By flow cytometric analysis with monoclonal antibody (MAb) 3C8 against HSP60, the reactive epitope in the HSP60 of H. pylori was detected on the surface of MKN45 cells. Furthermore, it was shown that gastric epithelial cells were positively stained with MAb 3C8 in one of two biopsy specimens examined. These results suggest that there is a common epitope showing homology between H. pylori HSP60 and human gastric epithelial cells.

Animals↗
PubMed1996

Analysis of of the epitopes recognized by mouse monoclonal antibodies directed to Yersinia enterocolitica heat-shock protein 60.

To determine amino acid sequences of the epitopes recognized by monoclonal antibodies (mAbs) 3C8 and 5C3 directed against Yersinia enterocolitica heat-shock protein (HSP60), a dot blot analysis was performed using synthesized peptides of Y. enterocolitica HSP60 such as peptides p316-342, p327-359, p340-366, p316-326, p316-321, p319-323, and p321-326 which represent positions of amino acids in Y. enterocolitica HSP60. The dot blot analysis revealed that 5C3 mAb reacted with p316-342, p316-326 and p321-326, and 3C8 mAb p316-342 and p316-326. These results indicate that the epitopes recognized by the mAbs were associated with eleven amino acids, Asp Leu Gly Gln Ala Lys Arg Val Val Ile Asn, of p316-326. The sequence homology between p316-326 of Y. enterocolitica HSP60 and the rest of the HSP60 family suggests that the five amino acids of Lys, Arg, Val, Ile and Asn, which are highly conserved in the HSP60 family, might be related with the epitope recognized by 3C8. In contrast, it was also demonstrated that three amino acids of Leu, Gly and Val, which are not well conserved in the HSP60 family, might be related to the epitope recognized by 5C3.

Amino Acid Sequence↗
PubMed1996

Identification and characterization of the Yersinia enterocolitica gsrA gene, which protectively responds to intracellular stress induced by macrophage phagocytosis and to extracellular environmental stress.

Yersinia enterocolitica is able to resist the microbicidal mechanisms of macrophages and to grow within phagocytic cells. Some bacteria including Y. enterocolitica have been shown to respond to the hostile environment in macrophages by producing a set of stress proteins which are also induced by environmental stresses. To understand the role of stress proteins in intracellular survival of bacteria, we identified and cloned a Y. enterocolitica gene, called gsrA (global stress requirement). The gsrA gene was identified because its insertional inactivation by a transposon resulted in the inability of the organism to grow at an elevated temperature and to survive within macrophages after phagocytosis. The gsrA gene was sequenced and shown to encode a basic, 49,500-Da protein. The GsrA protein shows significant amino acid sequence homology to the HtrA stress protein which was originally identified in Escherichia coli. Furthermore, the genetically defined Y. enterocolitica gsrA mutant was constructed and characterized. The insertional mutation of gsrA resulted in inhibition of growth at temperatures above 39 degrees C and greatly increased susceptibility to oxidative and osmotic stresses. The mutant additionally lost the ability to survive and replicate within macrophages. These results, taken together, indicate that the gsrA gene is an essential component of the protection mechanism employed by Y. enterocolitica, allowing it to respond to the intracellular stress in macrophages as well as extracellular environmental stress.

Amino Acid Sequence↗
PubMed1996

Common antigenicity between Yersinia enterocolitica-derived heat-shock protein and the retina, and its role in uveitis.

Yersinia enterocolitica-derived heat-shock protein (HSP60) was recently demonstrated to be associated with certain systemic autoimmune diseases. A role for HSP60 is also suspected in the pathogenesis of some types of uveitis believed to involve autoimmune mechanisms, such as Behçet's disease. We report our results on the role of HSP60 in patients with uveitis. HSP60 was subjected to electrophoresis in immunoblot analysis, and then allowed to react with sera from patients with uveitis in order to detect the presence of anti-HSP60 antibody. Tissue extracts from human and bovine retina were also electrophoresed, and then treated with anti-HSP60 monoclonal antibodies to determine whether or not the antibodies recognized ocular tissues. Immunoblot analysis revealed anti-HSP60 antibodies in patient sera. Furthermore, anti-HSP60 monoclonal antibodies reacted against the 60-kD protein derived from human and bovine retinal extracts. These immunological cross-reactions between HSP60 and the retina demonstrate a common antigenicity. Furthermore, detection of specific antibody against HSP60 in patient sera suggests that this common antigenicity between HSP60 and the retina may be related to the pathogenesis of uveoretinitis in some cases.

Animals↗
PubMed1996

Radiographical evaluation of bone maturation in Japanese black beef cattle.

Epiphyseal ossification in the radius, ulna, metacarpus, proximal phalanx and tuber calcaneus was examined radiographically in Japanese Black beef cattle. The grade of standard ossification was assessed monthly for each epiphysis. Bone maturations could be divided into 8 grades for the distal radius and distal ulna, 7 grades for the distal metacarpus, 5 grades for the proximal phalanx, and 8 grades for the tuber calcaneus, respectively. The closure of the epiphyseal line completed at the earliest (12-14 months of age) on the proximal phalanx, and at the latest (35-37 months of age) on the distal ulna. Changes in gradings were steep at 0 to 5 months of age but became almost constant after 10 months of age in all the epiphyses. There were no significant differences in bone maturation between the cattle with different sex and breeding conditions.

Aging↗
PubMed1996

On the EEG component waves of multi-infarct dementia seniles.

Component waves of EEGs led from the F3-A1, C3-A1, O1-A1, and O2-A2 scalp regions of 24 multi-infarct dementia seniles (MID) patients (ages 58 to 85 years, average 73.3 years) and eight to 19 normal, healthy, adult (NA) subjects were obtained by autoregressive component analysis. Some differences in the component waves were demonstrated between the two groups of subjects. (1) The characteristics of the EEG component waves, including the natural, damping, and resonance frequencies, their power, regularity, etc. were determined, and compared between MID patients and NA subjects. (2) No significant difference was found between male and female patients in the occurrence rate of 11 types of component waves. (3) On the average, the alpha wave frequency was lower in MID patients. (4). Slow alpha waves (7.5 to 9.4 Hz) of MID patients were superior to those of NA subjects, whereas typical alpha waves (9.5 to 11.4 Hz) were inferior to those of NA subjects. (5) The power of alpha waves in the F3-A1 and C3-A1 regions of MID patients was superior to that of NA subjects, whereas the result was reversed in the O1-A1 and O2-A2 regions. However, there was less regularity of alpha waves in all regions among MID patients. (6) The theta wave frequency in all regions was higher in MID patients than in NA subjects. (7) Both the power and regularity of theta waves of MID patients were superior to those of NA subjects in all regions. (8) The average number of delta waves that appeared in the O1-A1 and O2-A2 regions was larger in MID patients than in NA subjects. EEG were led from the F3-A1, C3-A1, O1-A1, and O2-A2 scalp regions of multi-infarct dementia seniles (MID) patients, who had sleep disorders, such as reversed day-time sleep patterns or irregular sleep-wake patterns, frequently accompanied by behavior disorders, such as wandering, violent behavior, and/or delirium. Examination by the method of EEG pattern discrimination revealed some differences in EEG component waves in comparison with normal, healthy, adult (NA) subjects.

Adult↗
PubMed1996

The effect of Helicobacter pylori on gastric acid secretion by isolated parietal cells from a guinea pig. Association with production of vacuolating toxin by H. pylori.

BACKGROUND: One of the features of Helicobacter pylori infection in the human stomach seems to be disordered gastric acid secretion. The effect of vacuolating toxin (VT) produced by H. pylori on gastric acid secretion was examined. METHODS: VT(+)(toxigenic) and VT(-)(nontoxigenic) strains of H. pylori were cultured in brucella broth. The culture supernatant was added to isolated parietal cells, and acid secretion and intracellular adenosine 3'5'-cyclic phosphate (cAMP) and Ca2+ levels were measured with the 14C-aminopyrine (14C-AP) method, with 125I radioimmunoassay (RIA), and with the fura-2 fluorescence method, respectively. RESULTS: In the VT(+) strain a considerable inhibitory effect on 14C-AP accumulation was observed. However, the VT(-) strain had no significant effect on intracellular c-AMP and Ca2+. CONCLUSIONS: The VT(+) strain of H. pylori has an inhibitory effect on gastric acid secretion, whereas the VT(-) strain does not. This inhibitory effect was not associated with the response of second messengers. It is speculated that VT produced by H. pylori has a direct action on H(+)-K+ adenosine triphosphatase in parietal cells.

Animals↗
PubMed1996

Effects of 1-[3-(4-benzhydryl-1-piperazinyl)propyl]-3- (1H-imidazol-1-ylmethyl)-1H-indole-6-carboxylic acid with thromboxane A2 synthetase inhibitory and H1-blocking activities on anaphylactic bronchospasm.

1-[3-(4-Benzhydryl-1-piperazinyl)propyl]-3-(1H-imidazol-1-ylmethyl )- 1H-indole-6-carboxylic acid (CAS 172544-75-1, KY-234) was characterized pharmacologically. KY-234 (10(-9)-10(-6) mol/l) and ozagrel (10(-8)-10(-5) mol/l) inhibited the production of thromboxane A2 (TXA2) in rabbit platelets. KY-234 and pyrilamine at concentrations of 10(-9)-10(-6) mol/l relaxed the isolated guinea pig trachea contracted with histamine, while neither drug attenuated the heart rate increased by histamine. Cimetidine antagonized histamine in the right atrium but not in the trachea. KY-234 (10(-8)-10(-5) mol/l) and ozagrel (10(-7)-10(-4) mol/l), but not pyrilamine, attenuated the contraction induced by leukotriene D4 (LTD4) and platelet-activating factor in the lung parenchymal strips. In anesthetized guinea pigs, KY-234 (1-10 mg/kg p.o.) inhibited the LTD4- and histamine-induced bronchoconstriction. Ozagrel and terfenadine inhibited only the LTD4- and histamine-induced constrictions. KY-234 (3-30 mg/kg p.o.) inhibited the anaphylactic bronchoconstriction continuously for 15 min after antigen-challenge. Terfenadine (3-30 mg/kg p.o.) inhibited the constriction more strongly within the first 5 min (fast phase) than it did within 5 to 15 min (slow phase) after the challenge. Ozagrel (100 mg/kg p.o.) slightly attenuated only the constriction during the slow phase. These findings demonstrated that KY-234 has a selective TXA2 synthetase-inhibitory and H1-blocking activity and protects against anaphylactic bronchospasm more effectively than a TXA2 synthetase inhibitor or H1-blocker alone.

Anaphylaxis↗
PubMed1996

Induction and epitope analysis of Helicobacter pylori heat shock protein.

Induction of heat shock proteins (HSPs) was analyzed in Helicobacter pylori strains. With heat shock at 42 degrees C, a synthesized 60 kDa-HSP (HSP60) was detected on autoradiography. The expression of HSP60 on the cell surface of H. pylori was examined by flow cytometric analysis. All strains used in this study expressed HSP60 on the cell surface, although the intensity differed among the strains, depending on culture conditions. The reactivity of a monoclonal antibody (mAb), 3C8, directed against bacterial HSP60, with HSP60 derived from ten strains of H. pylori and with human gastric carcinoma cell HSP60 was examined by immunoblot analysis. An epitope that reacted with the mAb was detected in the HSP60 of H. pylori and on the surface of human gastric carcinoma cells.

Antibodies, Monoclonal↗
PubMed1995

Flow cytometric analysis using lipophilic dye PKH-2 for adhesion of Vibrio cholerae to Intestine 407 cells.

A comparative study of indirect and direct flow cytometric analysis for adherence of Vibrio cholerae to Intestine 407 cells was performed. The direct flow cytometric analysis employed the lipophilic dye PKH-2. It was concluded that direct flow cytometry using the lipophilic dye PKH-2 is useful and convenient for analyzing bacterium-host cell interactions, since it does not require any specific antibody as the first antibody.

Bacterial Adhesion↗
PubMed1995

Granulation in livers of mice infected with Salmonella typhimurium is caused by superoxide released from host phagocytes.

The pathophysiological roles of superoxide (O2.-) at the site of infection of facultative intracellular bacteria were examined in this study. To evaluate the actual in vivo generation of the superoxide, an ex vivo chemiluminescence assay was newly developed. When ICR mice were infected with a sublethal dose (8 x 10(4) CFU) of Salmonella typhimurium, the number of bacteria in the liver reached its peak at 5 days after infection (10(5.05) CFU/g of liver) and decreased thereafter. At 21 days after infection, the bacteria became undetectable. On the other hand, phorbol myristate 13-acetate-stimulated O2.- generation reached a maximum at 7 days after infection (mean photon count, 1,249 cps versus 28.8 cps before infection; n = 4) and decreased thereafter to a level similar to that before infection at 21 days after infection (28.8 cps). Histological examinations revealed that the total area of the lesions reached a peak at 7 days after infection (7.2 x 10(4) microns 2/10 visual fields). In the early phase, a microabscess with infiltration of polymorphonuclear cells was noted, and then, in the late stage, the lesion was replaced by granulation with mononuclear cell infiltration. When microscopic lesions were measured histologically, a significant correlation between the area of the lesions and phorbol myristate 13-acetate-stimulated O2.- generation was observed, which suggested that superoxide was responsible for the generation of the lesions. Modified superoxide dismutase, i.e., alpha-4-([6-(N-maleimido)hexanoyloxymethyl] cumyl)half-butyl-esterified poly(stylrene-co-malelic acid)-conjugated superoxide dismutase (SM-SOD), was then applied. When SM-SOD was administered to suppress the O2.- generation in vivo, the number of bacteria increased (10(6.1) CFU). However, the lesion formation was inhibited (total lesion area, 0.3 x 10(4) microns 2). These results suggest that the establishment of the microabscess and granuloma formation after S. typhimurium infection is not due to the bacteria per se but rather to the O2.- from the host's phagocytes. Two aspects of the O2.-, i.e., the bactericidal role and the tissue-injurious effect, were clearly demonstrated in this study. Therefore, the information obtained from these results is useful in designing treatment strategy for similar kinds of infection.

Animals↗
PubMed1995

Listeria monocytogenes can grow in macrophages without the aid of proteins induced by environmental stresses.

Listeria monocytogenes is a facultative intracellular pathogen which is able to survive and grow within phagocytic cells. Some facultative intracellular bacteria have been shown to respond to the hostile environment within phagocytic cells by producing a set of stress proteins. Since L. monocytogenes has a mechanism for intracellular survival that is distinct from those of other bacteria, we studied the phenotypic response of the bacterium to phagocytosis by macrophages. After phagocytosis of L. monocytogenes EGD by J774-1 macrophage cells, the microorganism rapidly increased in numbers about 20-fold during an incubation period of 5 h. In this phase of phagocytosis, the selective induction of 32 proteins was observed by two-dimensional gel electrophoresis. The responses to the environmental stresses of heat and hydrogen peroxide were also studied, and it was found that 14 heat shock proteins and 13 oxidative stress proteins were induced. Five of the induced proteins were common to both heat and oxidative stresses. By amino acid sequencing analysis, homologs of DnaK and GroEL were confirmed among the heat shock proteins. A comparison of the autoradiograms of the two-dimensional gels revealed that none of these stress proteins were among the proteins induced by L. monocytogenes within the macrophages. This behavior is entirely different from that shown by other facultative intracellular pathogens. Stress proteins known to be induced by environmental stresses were absent in intracellularly grown L. monocytogenes in the present study. This absence could be due to the mechanism by which the microorganisms rapidly escape from this stressful environment at a very early phase of phagocytosis.

Amino Acid Sequence↗
PubMed1995

Thromboxane A2 synthetase inhibitors with histamine H1-blocking activity: synthesis and evaluation of a new series of indole derivatives.

A novel series of N-substituted 3-(1H-imidazol-1-ylmethyl)indole carboxylic acid derivatives were prepared and evaluated for thromboxane A2 (TXA2) synthetase-inhibitory and histaminergic H1-blocking activity. Among the compounds synthesized, indole-6-carboxylic acid derivatives showed higher activities than the other positional isomers of carboxylic acid. 1-[3-(4-Benzhydryl-1-piperazinyl)propyl]-3-(1H-imidazol-1-ylmethyl )-1H-indole-6-carboxylic acid (12) had the strongest thromboxane synthetase inhibitory activity (IC50 = 5 x 10(-8) M) and H1-blocking activity (IC50 = 8 x 10(-9) M).

Animals↗
PubMed1995

[Spontaneous subcapsular hemorrhage: a rare clinical presentation of renal cell carcinoma].

We present a case of renal subcapsular hemorrhage caused by a small renal cell carcinoma. The patient was a 52-year-old housewife, presenting abdominal pain and vomiting, of abrupt onset. Modern imaging modalities clearly visualized a perirenal or subcapsular hematoma in her left kidney, but no underlying pathology, was found even on the arteriogram. Relying on the statistics based on more than 100 reported cases with the spontaneous renal rupture, nephrectomy was carried out. The renal carcinoma was of granular cell type (G2), and classified as pT2, pN0 and pM0. Difficulties in making a correct diagnosis as to the pathology and therefore a rational decision for nephrectomy were also stressed.

Carcinoma, Renal Cell↗
PubMed1995

Adherence of Helicobacter pylori to cultured human gastric carcinoma cells.

AIM: To examine the binding activity of Helicobacter pylori to cultured gastric epithelial cells using flow cytometry. MATERIALS AND METHODS: We evaluated the adherence of 15 H. pylori strains to cultured gastric cancer (MKN45) cells by flow cytometric analysis. Other bacterial strains were also analysed for their adherence to MKN45 cells. In addition, we examined the effect of fetuin on the adherence of H. pylori to MKN45 cells. RESULTS: H. pylori strains adhered to MKN45 cells at rates of between 49 and 93.7%, with a mean of 75.3%. In contrast, the rates of Escherichia coli, Shigella flexneri, Vibrio cholerae and Yersinia enterocolitica adherence to MKN45 cells were 69.1, 5.9, 11.7 and 33.1%, respectively. Fetuin had no inhibitory effect on the adherence of H. pylori to MKN45 cells in the flow cytometric analysis. CONCLUSIONS: A flow cytometric analysis using MKN45 cells proved to be an objective and sensitive method for evaluating the adherence of H. pylori, showing close adherence between this organism and gastric epithelial cells.

Bacterial Adhesion↗