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161.
Jumpei Matsumoto Susumu Urakawa Yusaku Takamura Renato Malcher-Lopes Etsuro Hori Carlos Tomaz Taketoshi Ono Hisao Nishijo 《PloS one》2013,8(10)
A large number of studies have analyzed social and sexual interactions between rodents in relation to neural activity. Computerized video analysis has been successfully used to detect numerous behaviors quickly and objectively; however, to date only 2D video recording has been used, which cannot determine the 3D locations of animals and encounters difficulties in tracking animals when they are overlapping, e.g., when mounting. To overcome these limitations, we developed a novel 3D video analysis system for examining social and sexual interactions in rats. A 3D image was reconstructed by integrating images captured by multiple depth cameras at different viewpoints. The 3D positions of body parts of the rats were then estimated by fitting skeleton models of the rats to the 3D images using a physics-based fitting algorithm, and various behaviors were recognized based on the spatio-temporal patterns of the 3D movements of the body parts. Comparisons between the data collected by the 3D system and those by visual inspection indicated that this system could precisely estimate the 3D positions of body parts for 2 rats during social and sexual interactions with few manual interventions, and could compute the traces of the 2 animals even during mounting. We then analyzed the effects of AM-251 (a cannabinoid CB1 receptor antagonist) on male rat sexual behavior, and found that AM-251 decreased movements and trunk height before sexual behavior, but increased the duration of head-head contact during sexual behavior. These results demonstrate that the use of this 3D system in behavioral studies could open the door to new approaches for investigating the neuroscience of social and sexual behavior. 相似文献
162.
Ras guanyl nucleotide releasing proteins (RasGRPs) are guanine nucleotide exchange factors that activate Ras and Rap. We recently reported that xrasgrp2, which is a homolog of the human rasgrp2, plays a role in vasculogenesis and/or angiogenesis during early development of Xenopus embryos. However, the function of RasGRP2 in human vascular endothelium remains unknown. Therefore we aimed to analyze the function of human RasGRP2 in vascular endothelial cells. RasGRP2 overexpression did not increase Ras activation. However, it slightly increased Ras expression and increased proliferation in ECV304 cells. Furthermore, RasGRP2 overexpression increased Rap1 activation and cell–matrix adhesion in ECV304 cells. These data demonstrate that RasGRP2 increases cell viability and cell–matrix adhesion through increased Ras expression and Rap1 activation, respectively, in endothelial cells. 相似文献
163.
Kenichi Tanaka Masaaki Nakayama Makoto Kanno Hiroshi Kimura Kimio Watanabe Yoshihiro Tani Yuki Kusano Hodaka Suzuki Yoshimitsu Hayashi Koichi Asahi Keiji Sato Toshio Miyata Tsuyoshi Watanabe 《PloS one》2013,8(12)
Background
Advanced glycation end product (AGE) accumulation is thought to be a measure of cumulative metabolic stress that has been reported to independently predict cardiovascular disease in diabetes and renal failure. The aim of this study was to evaluate the association between AGE accumulation, measured as skin autofluorescence, and the progression of renal disease in pre-dialysis patients with chronic kidney disease (CKD).Methods
Skin autofluorescence was measured noninvasively with an autofluorescence reader at baseline in 449 pre-dialysis patients with CKD. The primary end point was defined as a doubling of serum creatinine and/or need for dialysis.Results
Thirty-three patients were lost to follow-up. Forty six patients reached the primary end point during the follow-up period (Median 39 months). Kaplan-Meier analysis showed a significantly higher risk of development of the primary end points in patients with skin autofluorescence levels above the optimal cut-off level of 2.31 arbitrary units, derived by receiver operator curve analysis. Cox regression analysis revealed that skin autofluorescence was an independent predictor of the primary end point, even after adjustment for age, gender, smoking history, diabetes, estimated glomerular filtration rate and proteinuria (adjusted hazard ratio 2.58, P = 0.004).Conclusions
Tissue accumulation of AGEs, measured as skin autofluorescence, is a strong and independent predictor of progression of CKD. Skin autofluorescence may be useful for risk stratification in this group of patients; further studies should clarify whether AGE accumulation could be one of the therapeutic targets to improve the prognosis of CKD. 相似文献164.
Keisuke Kirita Genichiro Ishii Rie Matsuwaki Yuki Matsumura Shigeki Umemura Shingo Matsumoto Kiyotaka Yoh Seiji Niho Koichi Goto Hironobu Ohmatsu Yuichiro Ohe Kanji Nagai Atsushi Ochiai 《PloS one》2013,8(12)
Background
Intralymphatic tumors in the extratumoral area are considered to represent the preceding phase of lymph node metastasis. The aim of this study was to clarify the biological properties of intralymphatic tumors susceptible to the development of lymph node metastasis, with special reference to the expression of cancer initiating/stem cell (CIC/CSC) related markers in cancer cells and the number of infiltrating stromal cells.Material and Methods
Primary lung adenocarcinomas with lymphatic permeation in the extratumoral area were retrospectively examined (n = 107). We examined the expression levels of CIC/CSC related markers including ALDH1, OCT4, NANOG, SOX2 and Caveolin-1 in the intralymphatic cancer cells to evaluate their relationship to lymph node metastasis. Moreover, the number of infiltrating stromal cells expressing CD34, α-smooth muscle actin, and CD204 were also evaluated.Results
Among the intralymphatic tissues, low ALDH1 expression in cancer cells, high SOX2 expression in cancer cells, and a high number of CD204(+) macrophages were independent predictive factors for lymph node metastasis (P = 0.004, P = 0.008, and P = 0.028, respectively). Among these factors, only low ALDH1 expression in cancer cells was significantly correlated with the farther spreading of lymph node metastasis (mediastinal lymph node, pathological N2) (P = 0.046) and the metastatic lymph node ratio (metastatic/resected) (P = 0.028). On the other hand, in the primary tumors, ALDH1 expression in the cancer cells was not associated with lymph node metastasis. Intralymphatic cancer cells expressing low ALDH1 levels exhibited lower E-cadherin expression levels than cancer cells with high levels of ALDH1 expression (P = 0.015).Conclusions
Intralymphatic cancer cells expressing low levels of ALDH1 and infiltrating macrophages expressing CD204 have a critical impact on lymph node metastasis. Our study also highlighted the significance of evaluating the biological properties of intralymphatic tumors for tumor metastasis. 相似文献165.
Intact maize plants prime for defensive action against herbivory in response to herbivore-induced plant volatiles (HIPVs) emitted from caterpillar-infested conspecific plants. The recent research showed that the primed defense in receiver plants that had been exposed to HIPVs was maintained for at least 5 d after exposure. Herbivory triggered the receiver plants to enhance the expression of a defense gene for trypsin inhibitor (TI). At the upstream sequence of a TI gene, non-methylated cytosine residues were observed in the genome of HIPV-exposed plants more frequently than in that of healthy plant volatile-exposed plants. These findings provide an innovative mechanism for the memory of HIPV-mediated habituation for plant defense. This mechanism and further innovations for priming of defenses via plant communications will contribute to the development of plant volatile-based pest management methods in agriculture and horticulture. 相似文献
166.
Yoshinori Takahashi Megan M. Young Jacob M. Serfass Tsukasa Hori Hong-Gang Wang 《Autophagy》2013,9(7):1107-1109
Evasion of apoptosis, which enables cells to survive and proliferate under metabolic stress, is one of the hallmarks of cancer. We have recently reported that SH3GLB1/Bif-1 functions as a haploinsufficient tumor suppressor to prevent the acquisition of apoptosis resistance and malignant transformation during Myc-driven lymphomagenesis. SH3GLB1 is a membrane curvature-inducing protein that interacts with BECN1 though UVRAG and regulates the post-Golgi trafficking of membrane-integrated ATG9A for autophagy. At the premalignant stage, allelic loss of Sh3glb1 enhances Myc-induced chromosomal instability and results in the upregulation of anti-apoptotic proteins, including MCL1 and BCL2L1. Notably, we found that Sh3glb1 haploinsufficiency increases mitochondrial mass in overproliferated prelymphomatous Eμ-Myc cells. Moreover, loss of Sh3glb1 suppresses autophagy-dependent mitochondrial clearance (mitophagy) in PARK2/Parkin-expressing mouse embryonic fibroblasts (MEFs) treated with the mitochondrial uncoupler CCCP. Interestingly, PARK2-expressing Sh3glb1-deficient cells accumulate ER-associated immature autophagosome-like structures after treatment with CCCP. Taken together, we propose a model of mitophagy in which SH3GLB1 together with the class III phosphatidylinositol 3-kinase complex II (PIK3C3CII) (PIK3R4-PIK3C3-BECN1-UVRAG) regulates the trafficking of ATG9A-containing Golgi-derived membranes (A9+GDMs) to damaged mitochondria for autophagosome formation to counteract oncogene-driven tumorigenesis. 相似文献
167.
Atsuko Miyagi Maki Kawai-Yamada Minori Uchimiya Noriyuki Ojima Koichi Suzuki Hirofumi Uchimiya 《Metabolomics : Official journal of the Metabolomic Society》2013,9(6):1254-1261
Evolution has shown the co-dependency between host plants and predators (insects), especially inevitable dependency of predators on plant biomass for securing their energy sources. It was postulated that NAD+ source used for major energy producing pathway is the glycerol-3-phosphate shuttle in insects. Using high throughput metabolomics approach, we found that larva of leaf beetle (Gastrophysa atrocyanea), which feed oxalate-rich plants (Rumex obtusifolius), possessed a unique mechanism for accumulating unusually high amounts of lactate. Similarly, larva of butterfly (Papilio machaon) fed with fennel (Foeniculum vulgare) accumulated lactate. Same butterfly also showed the elevated level of glycerol-3-phosphate equivalent to lactate. These evidences provide new insights into the mechanism underlying metabolite alteration between host plants and insect herbivores. 相似文献
168.
169.
Masaaki Konishi Seigo Sugiyama Koichi Sugamura Toshimitsu Nozaki Keisuke Ohba Junichi Matsubara Kenji Sakamoto Yasuhiro Nagayoshi Hitoshi Sumida Eiichi Akiyama Yasushi Matsuzawa Kentaro Sakamaki Satoshi Morita Kazuo Kimura Satoshi Umemura Hisao Ogawa 《PloS one》2013,8(4)
Background
Cardiac troponin is a specific biomarker for cardiomyocyte necrosis in acute coronary syndromes. Troponin release from the coronary circulation remains to be determined because of the lower sensitivity of the conventional assay. We sought to determine basal and angina-induced troponin release using a highly sensitive troponin assay.Methods and Results
The cardiac troponin T levels in serum sampled from the peripheral vein (PV), the aortic root (AO), and the coronary sinus (CS) were measured in 105 consecutive stable patients with coronary risk factor(s) and suspected coronary artery disease (CAD) and in 33 patients without CAD who underwent an acetylcholine provocation test. At baseline, there was a significant increase in the troponin levels from AO [9.0 (6.4, 13.1) pg/mL for median (25th, 75th percentiles)] to CS [10.3 (7.3, 15.5) pg/mL, p<0.001] in 96 (91.4%) patients and the difference was 1.1 (0.4, 2.1) pg/mL, which reflected basal transcardiac troponin release (TTR). TTR was positively correlated with PV levels (r = 0.22, p = 0.03). Male sex, left ventricular hypertrophy determined by echocardiography, T-wave inversion, and CAD correlated with elevated TTR defined as above: median, 1.1 pg/mL. A significant increase in TTR was noted in 17 patients with coronary spasms [0.6 (0.2, 1.2) pg/mL, p<0.01] but not in 16 patients without spasms [0.0 (−0.5, 0.9) pg/mL, p = 0.73] after the acetylcholine provocation.Conclusion
Basal TTR in the coronary circulation was observed in most of the patients with suspected CAD and risk factor(s). This sensitive assay detected myocardial ischemia-induced increases in TTR caused by coronary spasms. 相似文献170.
Dawn Sijin Nin Azhar Bin Ali Koichi Okumura Norio Asou Chien-Shing Chen Wee Joo Chng Matiullah Khan 《PloS one》2013,8(8)
The nuclear receptor co-repressor (N-CoR) is a key component of the generic co-repressor complex that plays an important role in the control of cellular growth and differentiation. As shown by us recently, the growth suppressive function of N-CoR largely relies on its capacity to repress Flt3, a key regulator of cellular gorwth during normal and malignant hematopoesis. We further demonstrated how de-repression of Flt3 due to the misfolded conformation dependent loss (MCDL) of N-CoR contributed to malignant growth in acute myeloid leukemia (AML). However, the molecular mechanism underlying the MCDL of N-CoR and its implication in AML pathogenesis is not fully understood. Here, we report that Akt-induced phosphorylation of N-CoR at the consensus Akt motif is crucial for its misfolding and subsequent loss in AML (AML-M5). N-CoR displayed significantly higher level of serine specific phosphorylation in almost all AML-M5 derived cells and was subjected to processing by AML-M5 specific aberrant protease activity. To identify the kinase linked to N-CoR phosphorylation, a library of activated kinases was screened with the extracts of AML cells; leading to the identification of Akt as the putative kinase linked to N-CoR phosphorylation. Consistent with this finding, a constitutively active Akt consistently phosphorylated N-CoR leading to its misfolding; while the therapeutic and genetic ablation of Akt largely abrogated the MCDL of N-CoR in AML-M5 cells. Site directed mutagenic analysis of N-CoR identified serine 1450 as the crucial residue whose phosphorylation by Akt was essential for the misfolding and loss of N-CoR protein. Moreover, Akt-induced phosphorylation of N-CoR contributed to the de-repression of Flt3, suggesting a cross talk between Akt signaling and N-CoR misfolding pathway in the pathogenesis of AML-M5. The N-CoR misfolding pathway could be the common downstream thread of pleiotropic Akt signaling activated by various oncogenic insults in some subtypes of leukemia and solid tumors. 相似文献