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491.
Tomohiro Ogawa Yumiko Sekiya Katsutoshi Yoshizato Kazuo Ikeda 《Biochemical and biophysical research communications》2010,391(1):316-552
MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expression through imperfect base pairing with the 3′ untranslated region (3′UTR) of target mRNA. We studied the regulation of alpha 1 (I) collagen (Col1A1) expression by miRNAs in human stellate cells, which are involved in liver fibrogenesis. Among miR-29b, -143, and -218, whose expressions were altered in response to transforming growth factor-β1 or interferon-α stimulation, miR-29b was the most effective suppressor of type I collagen at the mRNA and protein level via its direct binding to Col1A1 3′UTR. miR-29b also had an effect on SP1 expression. These results suggested that miR-29b is involved in the regulation of type I collagen expression by interferon-α in hepatic stellate cells. It is anticipated that miR-29b will be used for the regulation of stellate cell activation and lead to antifibrotic therapy. 相似文献
492.
Effect of endothelin dual receptor antagonist on VEGF levels in streptozotocin-induced diabetic rat retina 总被引:3,自引:0,他引:3
Masuzawa K Jesmin S Maeda S Zaedi S Shimojo N Miyauchi T Goto K 《Experimental biology and medicine (Maywood, N.J.)》2006,231(6):1090-1094
Diabetic retinopathy (DR), one of the most serious causes of blindness, is often associated with the upregulation of vascular endothelial growth factor (VEGF) in retina. Recently, leukocyte adhesion (leukostasis) is blamed for the occlusion of retinal capillary vascularity, which ultimately contributes to the progression of diabetic retinopathy. In addition, intercellular adhesion molecule-1 (ICAM-1), a representative factor for leukostasis, is increased in the diabetic retina. Endothelin (ET)-1, a potent vasoconstrictor peptide, is deeply linked to the pathogenesis of diabetic retinopathy. Different therapeutic interventions concerning VEGF have already been proposed to prevent diabetic retinopathy. However, no study yet has reported whether ET-1 dual receptor antagonist could alter the upregulated VEGF and ICAM-1 levels in the diabetic retina. The present study investigated the effect of ET(A/B) dual receptor antagonist (SB209670; 1 mg/rat/day) on the expression of VEGF and ICAM-1 in the diabetic rat retina. Diabetes was induced by intraperitoneal injection of streptozotocin (STZ; 65 mg/kg) in Sprague-Dawley rats, whereas control rats (non-DM control) received only citrate buffer. After 1 week, the STZ-administered rats were randomly divided into two groups: one group (DM+SB209670) received ET(A/B) dual receptor antagonist for 2 weeks, and a vehicle group (DM+vehicle) was treated only with saline. After the treatment period, the retinas were removed from the eyeballs. In DM+vehicle group, the VEGF expression of the retinas was significantly increased (32.8 pg/mg) in comparison to that in the non-DM control group (26.2 pg/mg); this upregulation of VEGF was reversed in the DM+SB209670 group (28.6 pg/mg). The expression of retinal ICAM-1 was increased in the DM+vehicle group (152.2 pg/mg) compared with the non-DM control group (121.6 pg/mg). However, SB209670 treatment did not alter the expression of retinal ICAM-1 level (154.8 pg/ml) in DM rats. Thus we conclude that an ET(A/B) dual receptor antagonist could reverse the expression level of VEGF in the diabetic retina while failing to normalize the upregulated ICAM-1 expression. 相似文献
493.
Katsutoshi Saruta Sadayori Hoshina Katsuhiko Machida 《Microbiology and immunology》1995,39(11):839-844
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. 相似文献
494.
Yoshiaki V. Nishimura Katsutoshi Sekine Kaori Chihama Kazunori Nakajima Mikio Hoshino Yo-ichi Nabeshima Takeshi Kawauchi 《The Journal of biological chemistry》2010,285(8):5878-5887
Neuronal migration is essential for proper cortical layer formation and brain function, because migration defects result in neurological disorders such as mental retardation and epilepsy. Neuronal migration is divided into several contiguous steps: early phase (multipolar mode), locomotion mode, and terminal translocation mode. The locomotion mode covers most of the migration route and thereby is the main contributor to cortical layer formation. However, analysis of the molecular mechanisms regulating this mode is difficult due to the secondary effects of defects at the early phase of migration. In this study, we established an ex vivo chemical inhibitor screening, allowing us to directly analyze the locomotion mode of migration. Roscovitine and PP2, inhibitors for Cdk5 and Src family kinases, respectively, suppressed the locomotion mode of migration. In line with this, a small percentage of Cdk5- or Src family kinase (Fyn)-knockdown cells exhibited locomoting morphology but retarded migration, although the majority of cells were stalled at the early phase of migration. We also showed that rottlerin, widely used as a specific inhibitor for protein kinase Cδ (PKCδ), suppressed the locomotion mode. Unexpectedly, however, the dominant-negative form as well as RNA interference for PKCδ hardly affected the locomotion, whereas they may disturb terminal translocation. In addition, we found JNK to be a potential downstream target of rottlerin. Taken together, our novel chemical inhibitor screening provides evidence that Cdk5 and Src family kinases regulate the locomotion mode of neuronal migration. It also uncovered roles for Fyn and PKCδ in the early and final phases of migration, respectively. 相似文献
495.
496.
The distribution of indole and tryptophan derivatives between sodium dodecyl sulfate (SDS) micellar and aqueous phases was analyzed using conventional methods of ultraviolet (UV) absorption spectroscopy and measurement of fluorescence quenching by succinimide. On the assumption of a simple pseudo-phase equilibrium between both phases the distribution coefficient was easily obtained by the measurement of the ratioR
pv of the absorbance intensity in the peak to that in the valley of the UV spectra or the fluorescence quenching constant Ksv. The possibilities and limitations of utilizing the ratio of the collisional quenching constant estimating from theK
sv value in the micellar phase to that in the aqueous phase for a measure of the polarity of the microenvironment around the tryptophan derivatives in the SDS micelle is discussed in comparison with theR
pv values for the UV spectra. The indole ring in the derivatives in the SDS micelle is localized near or on the micelle-water interface with its imino group directed toward the aqueous phase. Thus it can serve as a feasible model for interpreting the distribution coefficients andR
pv values obtained for the various indole and tryptophan derivatives.Abbreviations UV
ultraviolet
- SDS
sodium dodecyl sulfate
- ATEE
N-acetyl-l-tryptophan ethyl ester
- ATA
N-acetyl-l-tryptophan-amide
- CMC
critical micelle concentration 相似文献
497.
Sugiura Ko Tomita Sei Minamoto Toshifumi Mishina Tappei Iwata Akihisa Abe Tsukasa Yamamoto Satoshi Watanabe Katsutoshi 《Ichthyological Research》2021,68(1):152-157
Ichthyological Research - We report a novel species-specific primer set for detection of the endangered botiid loach Parabotia curtus in environmental waters. A primer test using DNA extracted from... 相似文献
498.
499.
The effect of pressure on deoxyribonucleic acid 总被引:1,自引:0,他引:1
500.
Katsutoshi Ishikawa Dr. Allen W. Schuetz S. K. San Francisco 《Molecular reproduction and development》1989,22(3):339-354
We report for the first time that oocyte nuclear and cytoplasmic maturation are triggered in vitro in non-hormone-treated amphibian (Rana pipiens) ovarian follicles following transient exposure to synthetic chymotrypsin inhibitor Nα-tosyl-L-phenylalanine-chloromethyl ketone (TPCK). The mechanism of action of TPCK in regulating oocyte maturation was investigated and compared to that induced by progesterone or pituitary hormone. Follicular oocytes failed to mature following continuous exposure to the same doses of TPCK in the presence or absence of progesterone. Continuous treatment of follicles with lower levels of TPCK occasionally induced GVBD in the absence of progesterone and augmented maturational effects of low levels of progesterone. TPCK induced maturation of intrafollicular oocytes without stimulating progesterone production and also induced maturation of naked oocytes. Stimulation of follicular progesterone synthesis following gonadotropin stimulation or addition of pregnenolone was inhibited by TPCK, indicating that TPCK affects metabolic processes in both the somatic and germinal components of the ovarian follicle. Oocyte maturation induced by either TPCK or progesterone was inhibited by cycloheximide, calcium-deficient medium, and forskolin. Results suggest that TPCK induces oocyte maturation independent of steroidogenesis via mechanisms similar to those triggered by progesterone involving protein synthesis, formation of cytoplasmic maturation-promoting factor (MPF), and changes in cAMP levels. Our data indicate that a chymotrypsin-like protease plays a role(s) in regulating the oocyte meiotic maturation process. 相似文献