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31.
Nakayama H 《Arthropod Structure & Development》2012,41(1):35-49
Detailed structure of the male genitalia of Anevrina is described. Hitherto unknown morphological characters of the internal sclerites relating to the epandrium and hypandrium are illustrated and elucidated. The subepandrial sclerite + bacilliform sclerites are distinctly modified, and the typical subepandrial sclerite is not recognizable. The right base of the medially shifted right surstylus is not connected to the posterior margin of the epandrium, and is directly supported by a robust bacilliform sclerite. The robust bacilliform sclerites are greatly developed inside the epandrium, and extended to three clasping components, the left surstylus, the medially shifted right surstylus and a pair of clasping lobes on the posteroventral margin of the right side of the epandrium. The upper lobe of a pair of clasping lobes on the right side of the epandrium is considered to originally have been situated on the left side and subsequently shifted to the right side. The plesiomorphic state of the clasping components relative to Anevrina is thought to be symmetrically four, comprising both the left and right surstyli and the posterior edge of both sides of the epandrium, indicating that the amazing phenomenon of cross-shifting of the clasping components has occurred in Anevrina. A cladogram generated based on the genitalic characters observed in this study shows sister groups within Anevrina, namely an Anevrina urbana-group comprised of A. urbana, A. setigera, A. olympiae, A. variabilis, A. thoracica, and an Anevrina unispinosa-group comprised of A. unispinosa, A. curvinervis, A. luggeri and A. macateei. 相似文献
32.
Prolactin induces MFG-E8 production in macrophages via transcription factor C/EBPβ-dependent pathway
Aziz MM Ishihara S Rumi MA Mishima Y Oshima N Kadota C Moriyama I Li YY Rahman FB Otani A Oka A Ishimura N Kadowaki Y Amano Y Kinoshita Y 《Apoptosis : an international journal on programmed cell death》2008,13(5):609-620
The lactogenic hormone prolactin (PRL) regulates milk protein gene expression in mammary glands. To maintain homeostatic balance
in the body, milk fat globule epidermal growth factor 8 (MFG-E8) is vital for phagocytic clearance of apoptotic cells. We
investigated the effects of PRL on MFG-E8 expression in macrophages by evaluating its promoter function. Macrophages were
stimulated with PRL, and the expression of MFG-E8 was determined using real-time PCR and Western blotting. The role of MFG-E8
on phagocytosis of apoptotic cells in PRL-treated macrophages was assessed using microscopy, while the response of PRL to
MFG-E8 expression was evaluated using luciferase assay. Following treatment with PRL, significant up-regulations of the PRL
receptor and MFG-E8 were observed in macrophages, though PRL-treated macrophages more efficiently engulfed apoptotic cells.
The results of MFG-E8 promoter analysis showed considerable up-regulation of promoter activity in macrophages following PRL
treatment and results from mutation analysis of the MFG-E8 promoter suggested that the C/EBPβ binding site was responsible
for PRL-induced activation of the MFG-E8 promoter. C/EBPβ activity was found to be up-regulated in PRL-treated cells as revealed
by an electrophoretic mobility shift assay (EMSA). In conclusion, PRL is a potent inducer of MFG-E8 expression in macrophages,
while its effect is mediated by the presence of a responsive element in the MFG-E8 promoter. 相似文献
33.
Yasuo Imanishi Masaaki Inaba Hitoshi Seki Hidenori Koyama Yoshiki Nishizawa Hirotoshi Morii Shuzo Otani 《The Journal of steroid biochemistry and molecular biology》1999,70(4-6)
1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) is known to be involved in regulating the proliferation of parathyroid cells and PTH synthesis through reactions involving its nuclear receptor. We evaluated the effects of 1,25-(OH)2D3 and its hexafluorinated analog, 26,26,26,27,27,27-hexafluoro-1,25-dihydroxyvitamin D3 (26,27-F6-1,25-(OH)2D3), on parathyroid cells. The 1,25-(OH)2D3 and 26,27-F6-1,25-(OH)2D3 each inhibited [3H]thymidine incorporation and ornithine decarboxylase (ODC) activity, which is important in cell proliferation, in primary cultured bovine parathyroid cells. The inhibitory effect of 26,27-F6-1,25-(OH)2D3 on PTH secretion from parathyroid cells was significantly more potent than that of 1,25-(OH)2D 3 between 10−11 M and 10−8 M. Study of 26,27-F6-1,25-(OH)2D3 metabolism in parathyroid cells in vitro elucidated its slower degradation than that of 1,25-(OH)2D3. After 48 h of incubation with [1β-3H]26,27-F6-1,25-(OH)2D3, two HPLC peaks, one for [1β-3H]26,27-F6-1,25-(OH)2D3, and a second larger peak for [1β-3H]26,27-F6-1,23(S),25-(OH)3D3, were detected. No metabolites were detected after the same period of incubation with 1,25-(OH)2[26,27-3H]D3. We observed that 26,27-F6-1,23(S),25-(OH)3D3 was as potent as 1,25-(OH)2D3 in inhibiting the proliferation of parathyroid cells.Data suggest that the greater biological activity of 26,27-F6-1,25-(OH)2D3 is explained by its slower metabolisms and by the retention of the biological potency of 26,27-F6-1,25-(OH)2D3 even after 23(S)-hydroxylation. 相似文献
34.
Yoshikawa F Banno Y Otani Y Yamaguchi Y Nagakura-Takagi Y Morita N Sato Y Saruta C Nishibe H Sadakata T Shinoda Y Hayashi K Mishima Y Baba H Furuichi T 《PloS one》2010,5(11):e13932
Background
Phospholipase D (PLD) catalyzes conversion of phosphatidylcholine into choline and phosphatidic acid, leading to a variety of intracellular signal transduction events. Two classical PLDs, PLD1 and PLD2, contain phosphatidylinositide-binding PX and PH domains and two conserved His-x-Lys-(x)4-Asp (HKD) motifs, which are critical for PLD activity. PLD4 officially belongs to the PLD family, because it possesses two HKD motifs. However, it lacks PX and PH domains and has a putative transmembrane domain instead. Nevertheless, little is known regarding expression, structure, and function of PLD4.Methodology/Principal Findings
PLD4 was analyzed in terms of expression, structure, and function. Expression was analyzed in developing mouse brains and non-neuronal tissues using microarray, in situ hybridization, immunohistochemistry, and immunocytochemistry. Structure was evaluated using bioinformatics analysis of protein domains, biochemical analyses of transmembrane property, and enzymatic deglycosylation. PLD activity was examined by choline release and transphosphatidylation assays. Results demonstrated low to modest, but characteristic, PLD4 mRNA expression in a subset of cells preferentially localized around white matter regions, including the corpus callosum and cerebellar white matter, during the first postnatal week. These PLD4 mRNA-expressing cells were identified as Iba1-positive microglia. In non-neuronal tissues, PLD4 mRNA expression was widespread, but predominantly distributed in the spleen. Intense PLD4 expression was detected around the marginal zone of the splenic red pulp, and splenic PLD4 protein recovered from subcellular membrane fractions was highly N-glycosylated. PLD4 was heterologously expressed in cell lines and localized in the endoplasmic reticulum and Golgi apparatus. Moreover, heterologously expressed PLD4 proteins did not exhibit PLD enzymatic activity.Conclusions/Significance
Results showed that PLD4 is a non-PLD, HKD motif-carrying, transmembrane glycoprotein localized in the endoplasmic reticulum and Golgi apparatus. The spatiotemporally restricted expression patterns suggested that PLD4 might play a role in common function(s) among microglia during early postnatal brain development and splenic marginal zone cells. 相似文献35.
Yonghui Jin Moritoshi Furu Yoichiro Kajita Hiroto Mitsui Michiko Ueda Tomitaka Nakayama Junya Toguchida 《Biochemical and biophysical research communications》2010,391(3):1471-2685
Hypoxia has been considered to affect the properties of tissue stem cells including mesenchymal stem cells (MSCs). Effects of long periods of exposure to hypoxia on human MSCs, however, have not been clearly demonstrated. MSCs cultured under normoxic conditions (20% pO2) ceased to proliferate after 15-25 population doublings, while MSCs cultured under hypoxic conditions (1% pO2) retained the ability to proliferate with an additional 8-20 population doublings. Most of the MSCs cultured under normoxic conditions were in a senescent state after 100 days, while few senescent cells were found in the hypoxic culture, which was associated with a down-regulation of p16 gene expression. MSCs cultured for 100 days under hypoxic conditions were superior to those cultured under normoxic conditions in the ability to differentiate into the chondro- and adipogenic, but not osteogenic, lineage. Among the molecules related to mitogen-activated protein kinase (MAPK) signaling pathways, extracellular signal regulated kinase (ERK) was significantly down-regulated by hypoxia, which helped to inhibit the up-regulation of p16 gene expression. Therefore, the hypoxic culture retained MSCs in an undifferentiated and senescence-free state through the down-regulation of p16 and ERK. 相似文献
36.
Dongsu Choi Yoko Watanabe Robert D. Guy Tetsuto Sugai Hiroto Toda Takayoshi Koike 《Acta Physiologiae Plantarum》2017,39(3):71
Key message
The black locust is adapted to elevated [CO 2 ] through changes in nitrogen allocation characteristics in leaves.Abstract
The black locust (Robinia pseudoacacia L.) is an invasive woody legume within Japan. This prolific species has a high photosynthetic rate and growth rate, and undergoes symbiosis with N2-fixing micro-organisms. To determine the effect of elevated CO2 concentration [CO2] on its photosynthetic characteristics, we studied the chlorophyll (Chl) and leaf nitrogen (N) content, and the leaf structure and N allocation patterns in the leaves and acetylene reduction activity after four growing seasons, in R. pseudoacacia. Our specimens were grown at ambient [CO2] (370 μmol mol?1) and at elevated [CO2] (500 μmol mol?1), using a free air CO2 enrichment (FACE) system. Net photosynthetic rate at growth [CO2] (A growth) and acetylene reduction activity were significantly higher, but maximum carboxylation rate of RuBisCo (V cmax), maximum rate of electron transport driving RUBP regeneration (J max), net photosynthetic rate under enhanced CO2 concentration and light saturation (A max), the N concentration in leaf, and in leaf mass per unit area (LMA) and ribulose-1,5-bisphosphate carboxylase oxygenase (RuBisCo) content were significantly lower grown at elevated [CO2] than at ambient [CO2]. We also found that RuBisCo/N were less at elevated [CO2], whereas Chl/N increased significantly. Allocation characteristics from N in leaves to photosynthetic proteins, NL (Light-harvesting complex: LHC, photosystem I and II: PSI and PSII) and other proteins also changed. When R. pseudoacacia was grown at elevated [CO2], the N allocation to RuBisCo (NR) decreased to a greater extent but NL and N remaining increased relative to specimens grown at ambient [CO2]. We suggest that N remobilization from RuBisCo is more efficient than from proteins of electron transport (NE), and from NL. These physiological responses of the black locust are significant as being an adaptation strategy to global environmental changes.37.
Adluri RS Thirunavukkarasu M Zhan L Dunna NR Akita Y Selvaraju V Otani H Sanchez JA Ho YS Maulik N 《PloS one》2012,7(3):e34790
Oxidative stress plays a critical role in the pathophysiology of cardiac failure, including the modulation of neovascularization following myocardial infarction (MI). Redox molecules thioredoxin (Trx) and glutaredoxin (Grx) superfamilies actively maintain intracellular thiol-redox homeostasis by scavenging reactive oxygen species. Among these two superfamilies, the pro-angiogenic function of Trx-1 has been reported in chronic MI model whereas similar role of Grx-1 remains uncertain. The present study attempts to establish the role of Grx-1 in neovascularization and ventricular remodeling following MI. Wild-type (WT) and Grx-1 transgenic (Grx-1(Tg/+)) mice were randomized into wild-type sham (WTS), Grx-1(Tg/+) Sham (Grx-1(Tg/+)S), WTMI, Grx-1(Tg/+)MI. MI was induced by permanent occlusion of the LAD coronary artery. Sham groups underwent identical time-matched surgical procedures without LAD ligation. Significant increase in arteriolar density was observed 7 days (d) after surgical intervention in the Grx-1(Tg/+)MI group as compared to the WTMI animals. Further, improvement in myocardial functional parameters 30 d after MI was observed including decreased LVIDs, LVIDd, increased ejection fraction and, fractional shortening was also observed in the Grx-1(Tg/+)MI group as compared to the WTMI animals. Moreover, attenuation of oxidative stress and apoptotic cardiomyocytes was observed in the Grx-1(Tg/+)MI group as compared to the WTMI animals. Increased expression of p-Akt, VEGF, Ang-1, Bcl-2, survivin and DNA binding activity of NF-κB were observed in the Grx-1(Tg/+)MI group when compared to WTMI animals as revealed by Western blot analysis and Gel-shift analysis, respectively. These results are the first to demonstrate that Grx-1 induces angiogenesis and diminishes ventricular remodeling apparently through neovascularization mediated by Akt, VEGF, Ang-1 and NF-κB as well as Bcl-2 and survivin-mediated anti-apoptotic pathway in the infarcted myocardium. 相似文献
38.
Hiroto Terasaki Satoru Kase Makoto Shirasawa Hiroki Otsuka Toshio Hisatomi Shozo Sonoda Susumu Ishida Tatsuro Ishibashi Taiji Sakamoto 《PloS one》2013,8(7)
Asymmetrical secretion of vascular endothelial growth factor (VEGF) by retinal pigment epithelial (RPE) cells in situ is critical for maintaining the homeostasis of the retina and choroid. VEGF is also involved in the development and progression of age-related macular degeneration (AMD). We studied the effect of tumor necrosis factor-α (TNF-α) on the secretion of VEGF in polarized and non-polarized RPE cells (P-RPE cells and N-RPE cells, respectively) in culture and in situ in rats. A subretinal injection of TNF-α caused a decrease in VEGF expression and choroidal atrophy. Porcine RPE cells were seeded on Transwell™ filters, and their maturation and polarization were confirmed by the asymmetrical VEGF secretion and trans electrical resistance. Exposure to TNF-α decreased the VEGF secretion in P-RPE cells but increased it in N-RPE cells in culture. TNF-α inactivated JNK in P-RPE cells but activated it in N-RPE cells, and TNF-α activated NF-κB in P-RPE cells but not in N-RPE cells. Inhibition of NF-κB activated JNK in both types of RPE cells indicating crosstalk between JNK and NF-κB. TNF-α induced the inhibitory effects of NF-κB on JNK in P-RPE cells because NF-κB is continuously inactivated. In N-RPE cells, however, it was not evident because NF-κB was already activated. The basic activation pattern of JNK and NF-κB and their crosstalk led to opposing responses of RPE cells to TNF-α. These results suggest that VEGF secretion under inflammatory conditions depends on cellular polarization, and the TNF-α-induced VEGF down-regulation may result in choroidal atrophy in polarized physiological RPE cells. TNF-α-induced VEGF up-regulation may cause neovascularization by non-polarized or non-physiological RPE cells. 相似文献
39.
40.
Hiroto Tatsumi Eiji Nakatani Takahiro Kanno Yoshiki Nariai Tatsuo Kagimura Joji Sekine 《PloS one》2015,10(9)