[C kinase activation and induction of HL 60 promyelocytic leukemia cell differentiation caused by roxithromycin].
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Anti-Bacterial Agents↗
Biomedical subjects
S Hoshina
Publications and source records attributed to S Hoshina.
[Diagnostic microbiology of DNA in septicemia].
Bacterial species encode rRNAs that are functionally and evolutionarily conserved. The nucleotide sequences of bacterial 16S ribosomal RNAs (16S rRNAs) diverge in regions of around 1,400 bases. Bacterial 16S rRNAs possess nine or more conserved "universal" sequences. Between each conserved region there are species specific sequences. These regions provide targets for clinical detection and diagnoses based on molecular hybridization for the polymerase chain reaction. We designed one base discriminating primer in 16S rRNA for the specific amplification of these regions and the primers in 16S-23S spacer regions of the rrn operon. These DNA-amplification based diagnosis of the septicemia showed multiple bacterial infection and indicated uncommon species of bacteria in the blood.
Bacteremia↗
Universality of energy and electron transfer processes in photosystem I.
Femtosecond transient absorption spectroscopy has been used to investigate the photoinduced energy and electron transfer processes in photosystem I (PS I) particles from cyanobacteria, green algae, and higher plants. At room temperature, the kinetics observed in all three species are very similar: Following 590 nm excitation, an equilibration process(es) with a 3.7-7.5 ps lifetime was observed, followed by a 19-24 ps process that is associated with trapping. In all three species long-wavelength pigments (pigments that absorb at longer wavelengths than the primary electron donor) were observed. The difference spectrum associated with reduction of the primary electron acceptor [Ao(-)-Ao) difference spectrum] was obtained for all three species. The (Ao(-)-Ao) difference spectra obtained from measurements using detergent-isolated PS I particles from spinach and Chlamydomonas reinhardtii are similar but clearly membrane fragments. In all three species the reduced primary electron acceptor (Ao(-)) is reoxidized extremely rapidly, in about 20 ps. The difference spectrum associated with Ao reduction appears to contain contributions from more than a single chlorophyll pigment.
Animals↗
Rapid identification of Streptococcus pneumoniae by PCR amplification of ribosomal DNA spacer region.
Streptococcus pneumoniae is one of the important human pathogens in clinical microbiology. A polymerase chain reaction assay was designed to detect and identify S. pneumoniae through amplification of the ribosomal DNA spacer regions between the pneumococcal 16S-23S ribosomal RNA genes. Thirty-two Streptococcus and non-Streptococcus strains were tested to verify the specificity of the assay, and only S. pneumoniae strains gave a positive reaction. This method is a powerful technique for the rapid identification of S. pneumoniae.
Bacteriological Techniques↗
Expression of platelet-derived endothelial cell growth factor/thymidine phosphorylase in human breast cancer.
We have investigated the expression of platelet-derived endothelial-cell growth factor/thymidine phosphorylase (PD-ECGF/dThdPase) in human breast-cancer tissues by the immunocytochemical method using anti-PD-ECGF/dThdPase monoclonal antibody. Out of 100 invasive-ductal-carcinoma tissue samples, 39 (39%) were evaluated as PD-ECGF/dThdPase-positive. The expression of PD-ECGF/dThdPase was identified mainly in the cytoplasma of tumor cells. The expression of PD-ECGF/dThdPase was significantly associated with the microvessel density assessed by immunostaining to factor-VIII-related-antigen (p < 0.05). However, there was no correlation between expression of PD-ECGF/dThdPase and menopausal status, tumor size, axillary lymph-node metastases, hormone-receptor status, epidermal-growth-factor receptor, or erb-B-2-protein and p53-protein expression. We suggest that expression of PD-ECGF/dThdPase plays an important role in the promotion of angiogenesis in human breast cancer.
Antibodies, Monoclonal↗
A macrolide antibiotic, roxithromycin, inhibits the growth of human myeloid leukemia HL60 cells by producing multinucleate cells.
The antiproliferative effect of roxithromycin (RXM) was studied using human myeloid leukemia HL60 cells. RXM inhibited the growth of HL60 cells in a concentration-dependent manner, and significantly inhibited growth at concentrations above 75 microM. This growth inhibition was not associated with specific cell cycle arrest and DNA synthesis was not impaired. In addition, the number of viable cells remained almost unchanged in the presence of 100 microM RXM. RXM induced growth inhibition at least partly by the formation of multinucleate cells. Both flowcytometric and morphological examination revealed that more than 40% of the RXM-treated cells were binucleate. These findings demonstrate that RXM is a potent new modulator of cell cycle progression in HL60 cells and suggest that the inhibition of cytokinesis by this drug may provide a new model for studying mitosis.
Bromodeoxyuridine↗
Genetic identification of Staphylococcus aureus by polymerase chain reaction using single-base-pair mismatch in 16S ribosomal RNA gene.
Staphylococcus aureus is the most predominant and important pathogen in clinical microbiology. A DNA amplification assay using the polymerase chain reaction (PCR) was designed to identify S. aureus through a single-base-pair mismatch in the sequences of staphylococcal 16S ribosomal RNA (16S rRNA) genes. It was able to detect and identify S. aureus without requiring additional analytical techniques. Twenty-eight staphylococcal and non-staphylococcal strains were tested to verify the specificity of the assay, and only S. aureus strains gave a positive reaction. It may be possible to provide immediate and exact information for the identification of S. aureus.
Base Sequence↗
[Significance of tumor angiogenesis as an independent prognostic factor in axillary node-negative breast cancer].
The value of tumor angiogenesis, EGFR and c-erbB-2 oncoprotein, a long with p 53 protein expression for predicting relapse-free survival was investigated in 110 node-negative breast cancer patients. The grade of neovascularization was assessed by the microvessel density which was obtained by an immunocytochemical staining by factor VIII-related antigen. EGFR, c-erbB-2 oncoprotein and p 53 oncoprotein were also determined by immunocytochemical assay. Univariate analysis showed no statistical significance of EGFR, c-erbB-2 and p53 status as a prognostic indicator. However, the microvessel density was a significant predictor of relapse-free survival. Patients with over 100 counts of factor VIII-RA positive cells per mm2 field in the most active areas of neovascularization showed significantly poorer prognosis compared to those with less than 100 counts (p < 0.005). Multivariate analysis demonstrated that microvessel density was an independent prognostic indicator in node-negative breast cancer patients (p < 0.0005). It was suggested that microvessel density might be of use in selecting the high-risk group in node-negative breast cancer patients needing adjuvant therapies.
Adenocarcinoma↗
Vascular endothelial growth factor and platelet-derived endothelial cell growth factor are frequently coexpressed in highly vascularized human breast cancer.
Vascular endothelial growth factor (VEGF) and platelet-derived endothelial cell growth factor (PD-ECGF) are known to be angiogenic growth factors in vitro and in vivo. In this study, we have investigated the relationship between VEGF expression and PD-ECGF expression in human breast cancer tissues using immunocytochemical methods. Of 152 primary breast cancers, 84 (55.3%) and 71 (46.7%) were positive for VEGF and PD-ECGF, respectively. Fifty-three (63. 1%) of 84 VEGF-positive tumors had a PD-ECGF-positive phenotype, whereas only 18 (26.5%) of 68 VEGF-negative tumors had a PD-ECGF-positive phenotype. There was a significant correlation between the VEGF expression and PD-ECGF expression (P < 0.01). As a single factor, VEGF expression and PD-ECGF expression were significantly associated with an increase in the microvessel density assessed by the immunocytochemical analysis using antifactor VIII-related antigen mAb. Interestingly, in addition, of 53 tumors with more than 100 microvessel counts/1 mm2, 40 (75.5%) had both VEGF- and PD-ECGF-positive phenotypes. It was found that VEGF and PD-ECGF were frequently coexpressed in highly vascularized tumors with high microvessel counts. It is suggested that VEGF and PD-ECGF might cooperatively function in the neovascularization of human breast cancer.
Breast Neoplasms↗
Association of vascular endothelial growth factor expression with tumor angiogenesis and with early relapse in primary breast cancer.
Angiogenesis is an independent prognostic indicator in breast cancer. In this report, the relationship between expression of vascular endothelial growth factor (VEGF; a selective mitogen for endothelial cells) and the microvessel density was examined in 103 primary breast cancers. The expression of VEGF was evaluated by immunocytochemical staining using anti-VEGF antibody. The microvessel density, which was determined by immunostaining for factor VIII antigen, in VEGF-rich tumors was clearly higher than that in VEGF-poor tumors (P < 0.01). There was a good correlation between VEGF expression and the increment of microvessel density. Furthermore, postoperative survey demonstrated that the relapse-free survival rate of VEGF-rich tumors was significantly worse than that of VEGF-poor tumors. It was suggested that the expression of VEGF is closely associated with the promotion of angiogenesis and with early relapse in primary breast cancer.
Base Sequence↗
[Tumor angiogenesis in breast cancer: significance of vessel density as a prognostic indicator].
Clinical usefulness, particularly significance as a prognostic indicator, of tumor angiogenesis, was investigated in primary breast cancer patients. Angiogenesis was evaluated by an immunostaining to factor VIII antigen, which is an endothelial marker. Out of 220 primary breast cancer patients, 54 were included in the high vessel density group with over 100 counts of factor VIII positive cells/x200 microscopic field. The relapse-free survival rate of the high vessel density group was significantly worse than that of the low vessel density group with less than 100 vessel counts (p < 0.01). A multivariate analysis demonstrated that vessel density is an independent prognostic indicator as potent as nodal status. It was concluded that tumor angiogenesis is a new and potent prognostic indicator in primary breast cancer patients.
Antigens, Neoplasm↗
[Significance of overexpression of p53 protein in human breast cancer].
Overexpression of p53 protein was examined by immunohistochemical assay. In 143 primary breast cancer patients, consisting of 18 patients with family history of breast cancer or past history of breast cancer and 125 patients with no such histories. In the later 125 patients, overexpression of p53 was shown in 42 patients (33.6%), however in the former 18 patients, p53 overexpression was found in 15 (83.3%). It was suggested that p53 protein is frequently overexpressed in patients with high risks like history of breast cancer and family history of breast. On the other hand, regarding the value of p53 overexpression as a prognostic indicator, an univariate analysis demonstrated that the relapse free survival of patients with over 50% p53 positive all rate was significantly worse compared to that of patients with less than 50% p53 positive all rate (p < 0.05). However multivariate analysis did not demonstrate the significant value (p < 0.1), suggesting that overexpression of p53 is marginal as a prognostic indicator.
Breast Neoplasms↗
Zinc as modulator of oxygenation function and stabilizer of quaternary structure in earthworm hemoglobin.
Blood of the earthworm Pheretima hilgendorfi contains 10.7 mM Ca, 2.0 mM Mg, 75.5 mM Na, 5.9 mM K, 0.9 mM Zn and 0.3 mM Mn. Some of these cations cannot be removed completely from the blood by dialysis, and 36 atoms of Ca, 1-3 atoms of Mg and 1-2 atoms of Zn per 164 atoms of Fe were retained in purified preparation of the hemoglobin (Hb). At physiological pH, oxygen affinity and the Hill coefficient at half saturation (n1/2 value) of the Hb increased in the presence of 100 mM of Ca, Mg or Na. These effects were in the order of Ca > Mg > Na. At physiological concentration, however, the effect of each of these three cations on oxygenation was rather small. On the other hand, Zn gave a remarkable effect at less than 1 mM. This suggests a possibility that Zn acts as a primal modulator for the oxygenation function of the Hb in vivo. Oxygenation data at various pH values in the presence of each cation strongly suggest that Zn binds to a site different from those for the other three cations. Zn at a concentration of only 1 mM protected considerably the dissociation of the whole molecule to smaller components at alkaline pH and Zn thus contributes to the stabilization of the quaternary structure of the Hb.
Animals↗
Effects of core-level excitation on the F-center formation in KCl and KBr at liquid-helium temperature.
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Journal Article↗
Effects of a fecapentaene on protein kinase C.
Protein kinase C (PKC) is a Ca2(+)- and phospholipid-dependent serine and threonine protein kinase which binds and is activated by tumor promoters such as the phorbol ester 12-0-tetradecanoylphorbol-13-acetate (TPA). PKC can be activated in vitro by phosphatidylserine (PS) plus Ca2+. We report here that the compound fecapentaene-12 can replace the requirement for PS in the activation of PKC by Ca2+. In addition, at low concentrations fecapentaene-12 can enhance the activation of PKC by Ca2+ and PS. It can also either enhance or inhibit activation of PKC by the tumor promoter teleocidin, depending on the assay conditions. These results are of interest since fecapentaene is known to be a potent mutagen that is produced by Bacteroides species present in the lumen of the human colon. The present studies raise the possibility that this compound might also play a role in colon cancer by altering the activity of PKC.
Animals↗
[Hemofiltration devices].
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Hemofiltration↗
Growth factor-induced DNA synthesis in cells that overproduce protein kinase C.
In previous studies (Housey et al.: Cell 52:343-354, 1988), our laboratory demonstrated that a cell line R6-PKC3 that stably overproduces high levels of the beta 1 isoform of PKC displayed several abnormalities in growth control, and these phenotypic changes were also markedly enhanced when the cells were exposed to TPA. The present studies indicate that these cells also display marked changes in their response to certain growth factors. A striking finding was that several agents when tested alone in serum-free medium, including EGF, PDGF, TPA, teleocidin, and OAG, stimulated DNA synthesis in quiescent R6-PKC3 cells but had a negligible effect in quiescent R6-C1 cells, a vector control cell line with normal levels of PKC. R6-PKC3 cells also show an exaggerated response to very low concentrations of serum, when compared to R6-C1 control cells. These studies provide direct genetic evidence that alterations in cellular levels of PKC can markedly influence the responses of cells to specific growth factors.
Animals↗
Characterization and N-terminal sequence of a 5 kDa polypeptide in the photosystem I core complex from spinach.
Photosystem I core complexes were isolated from spinach photosystem I particles after heat treatment in the presence of 50% (v/v) ethylene glycol (heat/EG treatment). The core complex from 58 degrees C/EG-treated particles was composed of polypeptides with apparent molecular masses of 63, 60 and 5 kDA; this complex contained the iron sulfur center Fx but lacked center FA and FB. The core complex obtained from the 70 degrees C/EG-treated preparation lacked FX and contained a lesser amount of the 5 kDa polypeptide. The N-terminal amino acid sequence of the 5 kDa polypeptide did not correspond to the sequence derived from any possible reading frame in the chloroplast DNA of liverwort or tobacco. Twelve of the first 29 N-terminal amino acids were hydrophobic, suggesting that this protein is intrinsic to the photosystem I reaction center.
Amino Acid Sequence↗