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991.
The point of this study was to examine the presence or absence of cytokine-positive cells by means of immunohistochemical methods in the samples of inflamed gingival tissues obtained from an 11-year-old girl with Papillon-Lefevre syndrome (PLS). Interleukin-8 (IL-8)-positive cells were found to be present. In addition, IL-1alpha-and IL-1beta-positive cells were detected. No dysfunction in the phagocytosis and the bacterial killing of peripheral blood polymorphonuclear neutrophils (PMNs) was observed in this patient. Our findings suggest that these cytokines may be members responsible for modulating the process of rapidly progressive periodontitis for patient with PLS. 相似文献
992.
Maeda Y Tanaka E Fujiwara M Watanabe R Furusawa H Matsu T Nakahara H Nanba K Higashi S Setoguchi T 《The Journal of steroid biochemistry and molecular biology》2002,81(3):249-253
Gross cystic disease of the breast is one of the most common diseases of adult females. Breast cyst fluid contains various steroid hormones. In order to obtain more information about the concentrations of 4- and 5-ene steroids in human breast cyst fluids, levels of pregnenolone sulfate (PREGS), pregnenolone (PREG), dehydroepiandrosterone sulfate (DHEAS) and dehydroepiandrosterone (DHEA) were determined by high-performance liquid chromatography (HPLC). A total of 35 human breast cyst fluid samples, obtained from 35 patients (28-54 years old) were analyzed. Cyst fluid electrolytes were simultaneously determined. Levels of PREGS (mean+/-S.D.) were 26.9+/-20.0 micromol/l (N=35) and of PREG were <0.1 micromol/l. Levels of DHEAS and DHEA were 89.1+/-111.7 micromol/l (N=35) and 0.3+/-0.2 micromol/l (N=35), respectively. Cyst fluids were divided into two groups (types I and II) according to their electrolyte ratio (K(+)/Na(+)). The cysts of the type I group (K(+)/Na(+) >1.5) contained significantly higher levels of PREGS (39.9+/-21.1 micromol/l) and DHEAS (133.2+/-87.9 micromol/l) than those of the type II group (K(+)/Na(+) <1.5), the mean levels of which were 19.8+/-16.2 micromol/dl for PREGS, and 36.3+/-29.0 micromol/dl for DHEAS (P<0.05). PREGS and DHEAS levels in the cysts were significantly correlated (r=0.49; P<0.01). Human breast cyst fluids contain high concentration of DHEAS and PREGS, especially in the cyst fluids containing high K(+)/Na(+) ratios. 相似文献
993.
994.
Pleiotrophin/heparin-binding growth-associated molecule (HB-GAM) is a specific ligand of protein tyrosine phosphatase ζ (PTPζ)/receptor-like protein tyrosine phosphatase β (RPTPβ) expressed in the brain as a chondroitin sulfate proteoglycan. Pleiotrophin and PTPζ isoforms are localized along the radial glial fibers, a scaffold for neuronal migration, suggesting that these molecules are involved in migratory processes of neurons during brain development. In this study, we examined the roles of pleiotrophin-PTPζ interaction in the neuronal migration using cell migration assay systems with glass fibers and Boyden chambers. Pleiotrophin and poly-l-lysine coated on the substratums stimulated cell migration of cortical neurons, while laminin, fibronectin, and tenascin exerted almost no effect. Pleiotrophin-induced and poly-l-lysine–induced neuronal migrations showed significant differences in sensitivity to various molecules and reagents. Polyclonal antibodies against the extracellular domain of PTPζ, PTPζ-S, an extracellular secreted form of PTPζ, and sodium vanadate, a protein tyrosine phosphatase inhibitor, added into the culture medium strongly suppressed specifically the pleiotrophin-induced neuronal migration. Furthermore, chondroitin sulfate C but not chondroitin sulfate A inhibited pleiotrophin-induced neuronal migration, in good accordance with our previous findings that chondroitin sulfate constitutes a part of the pleiotrophin-binding site of PTPζ, and PTPζ-pleiotrophin binding is inhibited by chondroitin sulfate C but not by chondroitin sulfate A. Immunocytochemical analysis indicated that the transmembrane forms of PTPζ are expressed on the migrating neurons especially at the lamellipodia along the leading processes. These results suggest that PTPζ is involved in the neuronal migration as a neuronal receptor of pleiotrophin distributed along radial glial fibers. 相似文献
995.
Hermit crabs have two antipredator tactics: taking refuge in its shell and fleeing. We examined the following two hypotheses using the hermit crab Pagurus filholi : (1) hermit crabs change their preference for shell types that they take refuge in and/or change the timing of fleeing (i.e. the duration of refuge in the shell) when they perceive a predator threat; (2) the type of shell that a hermit crab occupies affects the fleeing tactic of the individual. Under the stimulus of a crushed conspecific, hermit crabs changed neither their preference for shell species nor their refuge duration. On the other hand, under the stimulus of the predatory crab Gaetice depressus , hermit crabs increased their preference for Batillaria cumingi shells, which provide superior protection against predators, and shortened their refuge duration in the shells even when they occupied those effective against predation. Refuge duration was longer in B. cumingi shells than in the more vulnerable shells of Homalopoma sangarense . These results suggest that both antipredator defences (changing shell and timing of fleeing) are induced by the stimulus of a predator, and the timing of fleeing is affected by the shell type occupied. 相似文献
996.
A new water-soluble N-protecting group, 2-[phenyl(methyl)sulfoniolethyloxycarbonyl tetrafluoroborate, has been prepared and its application to solid phase peptide synthesis in water has been studied. Leu-enkephalin amide was successfully synthesized in water by the solid phase method using this protecting group. 相似文献
997.
Hidetoshi Arakawa Shuji Nakashiro Akio Tsuji Masako Maeda 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1998,716(1-2)
We describe the development of a sensitive high-performance liquid chromatographic (HPLC) method for polymerase chain reaction (PCR) products using bisbenzimide (Hoechst 33258 dye) based fluorimetric detection. The detection limit and specificity for double-strand DNA detection are improved in comparison with HPLC with UV absorbance detection. This HPLC, using a column packed with diethylaminoethyl-bonded non-porous resin particles, was applied to the detection of allele-specific PCR and restriction fragment length polymorphism analysis. We also developed a hybridization method analyzed by HPLC. DNA fragments (149 bp) containing the mutation site (C→A,G,T) in the N-ras gene were amplified by PCR. Fluorescein isothiocyanate (FITC)-labeled DNA probes were also prepared by PCR using FITC-labeled 5′ primer. Analysis of mutation was performed by the separation of a hybrid and non-reactive DNA probe with HPLC with fluorimetric detection after the hybridization of target DNA (149 bp) and a FITC DNA probe. The effects of various factors on hybridization were examined to establish optimal assay conditions. Under the conditions determined, a point mutation in PCR products obtained from the N-ras gene could be detected specifically by this method. The analysis of PCR products by HPLC may potentially be useful for DNA diagnosis. 相似文献
998.
Hiroshi Sakagami Kazue Satoh Yoshiteru Ida Mahina Hosaka Hidetoshi Arakawa Masako Maeda 《Free radical biology & medicine》1998,25(9):1013-1020
The interaction between sodium ascorbate and dopamine was investigated by three different parameters: radical intensity, prooxidant action, and cytotoxicity induction. Sodium ascorbate and dopamine produced the doublet and quartet ESR signals under alkaline conditions (pH 8.0–9.5), respectively. Addition of increasing concentrations of sodium ascorbate completely scavenged the dopamine radical and replaced the latter with its own radical. Similarly, dopamine slightly, but significantly reduced the radical intensity of sodium ascorbate. These two compounds stimulated the methionine oxidation and hydrogen peroxide generation in culture medium, but in combination, their stimulation activities were weakened. Both of these two compounds dose-dependently reduced the viable cell number of human oral squamous carcinoma HSC-4 cells, and their cytotoxic activity was significantly reduced by catalase. When these two compounds were mixed together before adding to HSC-4 cells, both of their cytotoxic activities were diminished. The present study demonstrates the interaction between sodium ascorbate and dopamine, which might modify their biological activities and generation of nerve disorders such as Parkinson’s disease. 相似文献
999.
Sumi Matsui Mineko Fujimiya Junki Matsui Yoshikuni Amakata Tindaro Renda Hiroshi Kimura Toshihiro Maeda 《The Histochemical journal》1994,26(8):648-654
Summary The localization of [D-Ala2]deltorphin I, a -opioid receptor ligand, was studied in the lower respiratory tract of developing rats using an immunohistochemical method. [D-Ala2]-like immunoreactive cells were detected first in the principal bronchus as early as embryonic day 16. As embryos grew, positive cells became gradually visible everywhere from principal bronchi to respiratory bronchioles. The density of positive cells reached the highest level on embryonic day 21, but decreased gradually after birth. Positive cells were no longer seen on postnatal day 30 in any region of the airways. No positive cells were ever found in the trachea or alveoli of rats at any age studied. Ultrastructural examination indicated that the immunoreactive cells possessed a similar morphology to serous or Clara cells of the respiratory epithelium. Immunoreaction products tended to locate at the apical cytoplasm of positive cells. The result suggests that [D-Ala2]-like molecule(s) may be expressed transiently in serous cells or Clara cells, or both, of the rat bronchopulmonary tract. Such a molecule may act as a pulmonary growth-promoting or a differentiation-initiating factor in an early period of lung development. 相似文献
1000.
Chong-Hua Yao Sohei Kitazawa Takahiro Fujimori Sakan Maeda 《Biotechnic & histochemistry》1993,68(3):169-174
A bromodeoxyuridine (BrdU) labeled DNA probe was used for in situ hybridization at the electron microscopic (EM) level. A BrdU labeled DNA probe was hybridized in situ to cryostat sections of paraformaldehyde fixed OCT compound embedded cultured HL-60 cells. After hybridization, some sections were incubated with FITC-conjugated anti-BrdU monoclonal antibody for fluorescence microscopy (FM). and others were embedded in Quetol for electron microscopy (EM). The ultrathin sections of Quetol-embedded specimens were incubated with the anti-BrdU monoclonal antibody and the immunoglobulin: gold colloid. In both FM and EM studies, the signals were concentrated in the rough endoplasmic reticulum. Moreover, some label was arranged from the nucleus to the cytoplasm at the EM level. Relatively simple methods using the BrdU labeled DNA probe for the detection of the defined nucleic acid sequence with reasonable tissue preservation and high resolution are described here. This method may be useful for developmental and disease related studies of specific mRNA in cells and tissues. 相似文献