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671.
Shun Akaeda Yasushi Hirota Yamato Fukui Shizu Aikawa Ryoko ShimizuHirota Tetsuaki Kaku Mona Gebril Tomoyuki Hirata Takehiro Hiraoka Mitsunori Matsuo Hirofumi Haraguchi Mayuko SaitoKanatani Norihiko Takeda Tomoyuki Fujii Yutaka Osuga 《EMBO reports》2021,22(2)
Retinoblastoma protein (RB) encoded by Rb1 is a prominent inducer of cell cycle arrest (CCA). The hormone progesterone (P4) promotes CCA in the uterine epithelium and previous studies indicated that P4 activates RB by reducing the phosphorylated, inactive form of RB. Here, we show that embryo implantation is impaired in uterine‐specific Rb1 knockout mice. We observe persistent cell proliferation of the Rb1‐deficient uterine epithelium until embryo attachment, loss of epithelial necroptosis, and trophoblast phagocytosis, which correlates with subsequent embryo invasion failure, indicating that Rb1‐induced CCA and necroptosis of uterine epithelium are involved in embryo invasion. Pre‐implantation P4 supplementation is sufficient to restore these defects and embryo invasion. In Rb1‐deficient uterine epithelial cells, TNFα‐primed necroptosis is impaired, which is rescued by the treatment with a CCA inducer thymidine or P4 through the upregulation of TNF receptor type 2. TNFα is expressed in the luminal epithelium and the embryo at the embryo attachment site. These results provide evidence that uterine Rb1‐induced CCA is involved in TNFα‐primed epithelial necroptosis at the implantation site for successful embryo invasion. 相似文献
672.
Marie Saito Miyuki Tanaka Eriko Misawa Ruiquing Yao Kazumi Nabeshima Kouji Yamauchi 《Bioscience, biotechnology, and biochemistry》2016,80(7):1416-1424
This study reports the effects of oral Aloe vera gel powder (AVGP) containing Aloe sterols on skin elasticity and the extracellular matrix in ultraviolet B (UVB)-irradiated hairless mice. Ten-week-old hairless mice were fed diets containing 0.3% AVGP for 8 weeks and irradiated UVB for 6 weeks. Mice treated with AVGP showed significant prevention of the UVB-induced decrease in skin elasticity. To investigate the mechanism underlying this suppression of skin elasticity loss, we measured the expression of matrix metalloproteinase (MMP)-2, -9, and -13. AVGP prevented both the UVB-induced increases in MMPs expressions. Moreover, we investigated hyaluronic acid (HA) content of mice dorsal skin and gene expression of HA synthase-2 (Has2). In the results, AVGP oral administration prevented UVB-induced decreasing in skin HA content and Has2 expression and attenuates the UVB-induced decrease in serum adiponectin, which promotes Has2 expression. These results suggested that AVGP has the ability to prevent the skin photoaging. 相似文献
673.
Yutaro Kimura Yutaka Fukuda Rumi Otsu Juwanen Yu Sayaka Mino Satoru Misawa Satoshi Maruyama Yuta Ikeda Remi Miyamachi Hiroshi Noguchi Satoshi Kato Yasuhito Yamamoto Tomoo Sawabe 《Environmental microbiology》2023,25(12):2834-2850
Polybutylene succinate (PBS) is an eco-friendly green plastic. However, PBS was shown as being non-biodegradable in marine environments, and up until now, only a limited number of PBS-degrading marine microbes have been discovered. We first set up in vitro PBS- and PBSA (polybutylene succinate adipate)-plastispheres to characterize novel PBS-degrading marine microbes. Microbial growth and oxygen consumption were observed in both PBS- and PBSA-plastispheres enriched with natural seawater collected from Usujiri, Hokkaido, Japan, and Vibrionaceae and Pseudoalteromonadaceae were significantly enriched on these films. Further gene identification indicated that vibrios belonging to the Gazogenes clade possess genes related to a PBS degrading enzyme (PBSase). The PBS degradation assay for six Gazogenes clade vibrios identified Vibrio ruber, Vibrio rhizosphaerae, and Vibrio spartinae as being capable of degrading PBS. We further identified the gene responsible for PBSase from the type strain of V. ruber, and the purified recombinant vibrio PBSase was found to have low-temperature adaptation and was active under high NaCl concentrations. We also provided docking models between the vibrio PBSase and PBS and PBSA units to show how vibrio PBSase interacts with each substrate compared to the Acidovorax PBSase. These results could contribute to a more sustainable society through further utilization of PBS in marine environments and plastic recycling. 相似文献
674.
Yuji Yoshiko Jane E Aubin Norihiko Maeda 《The journal of histochemistry and cytochemistry》2002,50(4):483-492
STC1, a mammalian homologue of stanniocalcin (STC) which plays a major role in calcium/phosphate homeostasis in fish, has been recently isolated. We have characterized the spatiotemporal distribution of STC1 mRNA and protein during mouse embryonic development generally and osteogenesis specifically. Northern blotting analysis of whole embryos showed that STC1 mRNA is highly and differentially expressed during embryogenesis. By in situ hybridization, STC1 mRNA was detected early in mesenchymal condensations and was then found to be highly expressed in perichondrial cells, periosteal cells, and then osteoblasts during endochondral bone formation. In bones forming by intramembranous ossification, STC1 mRNA was not detected until osteogenic cells appeared. The cellular distribution of STC1 protein closely corresponded to that of its mRNA, but the protein was also detected in hypertrophic chondrocytes. In the MC3T3-E1 osteogenic cell model, STC1 protein and mRNA were detectable throughout proliferation and differentiation stages but levels were relatively higher late during nodule formation/mineralization phases. For comparison, STC1 mRNA was also found in epithelial cells of both embryonic and adult intestine that had not previously been described among tissues responsive to calcium/phosphate transport. These results suggest that STC1 is expressed in a time- and cell-specific manner and may play an autocrine/paracrine role during osteoblast development and bone formation. 相似文献
675.
Ikuo Takashima Yumi Imai Norihiko Itoh Hiroaki Kariwa Nobuo Hashimoto 《Microbiology and immunology》1996,40(1):21-26
The polymerase chain reaction (PCR) targeting the ompA gene of Chlamydia psittaci was evaluated for its ability to detect chlamydiae in fecal specimens of budgerigars as compared with isolation procedures using cell culture and embryonated egg inoculations. Several procedures for PCR template DNA preparation were compared so as to determine their detection levels for chlamydiae propagated in cell culture in the presence of fecal materials. Tween-20 and proteinase K treatments followed by centrifugation of the template DNA were found to be an appropriate procedure for DNA preparation for primary PCR. Subsequent nested PCR was shown to detect 4.8 IFU/ml or 84 particles/ml of chlamydiae. Chlamydiae in 50 fecal specimens from apparently healthy budgerigars were examined by nested PCR and several other methods. Nested PCR detected chlamydiae at a higher rate (12/50, 24%) than the isolation procedure in embryonated eggs (6/50, 12%). Primary PCR combined with the isolation procedure in cell culture gave a detection rate (5/50, 10%) similar to that of isolation from embryonated eggs. Detection rates by primary PCR (1/50, 2%) and in cell culture (0%) were inferior to the other procedures. 相似文献
676.
677.
Ichthyological Research - A new hardnose skate, Okamejei panayensis sp. nov., is described from a single specimen [304 mm in total length (TL), adult male] collected off Iloilo, Panay... 相似文献
678.
A methanogenic bacterium with the morphological and physiological properties of the genus Methanobrevibacter was isolated from the feces of a Japanese man who excreted methane in his breath. Indirect immunofluorescence staining revealed that the isolate had an antigenicity unrelated to that of any known members of the genus Methanobrevibacter. 相似文献
679.
K. Misawa T.M. Lee S. Ogawa 《Biochimica et Biophysica Acta (BBA)/General Subjects》1982,718(2):227-229
The exchange process of Mg2+ with ATP was found to be, in many cases, dominated by Mg2+ exchange between ATP and ATP-Mg (a bimolecular reaction) rather than the Mg2+ off-process from ATP-Mg to solutino (a unimolecular reaction). The Mg2+ off-rate from ATP-Mg and the rate constant of the bimolecular reaction were determined at 10 and 25°C at pH. 7.3, using 31P-NMR at 145.7 MHz. At this resonance frequency intermediate to slow exchange phenomena with respect to the NMR time scale of 2.5·103 s?1 were observed in ATP resonances. Various implications of these results to studies of biological systems have been pointed out. 相似文献