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991.

Background

Localized hypersensitivity reaction, delayed arterial healing, and neoatherosclerosis inside the stent have been suggested as the underlying pathologic mechanisms of very late stent thrombosis (VLST) of drug-eluting stent (DES). The present study sought to explore the prevalence of inflammatory cell infiltrates and evidence for fragments of atherosclerotic plaques in the aspirated thrombi in patients with DES VLST.

Methods and Results

From April 2004 to September 2012, 48 patients with stent thrombosis (ST) of DES underwent thrombus aspiration with retrieved material sufficient for the histopathologic analysis; early ST (EST, within 30 days): N = 17, late ST (LST, between 31 and 365 days): N = 7, and very late ST (VLST, >1 year): N = 24. Eosinophil fraction in the aspirated thrombi was significantly higher in patients with VLST (8.2±5.7%) as compared with those with EST (4.3±3.0%) and LST (5.5±3.8%) (P = 0.03). Eosinophil fraction in the aspirated thrombi was significantly higher in 12 VLST patients with angiographic peri-stent contrast staining (PSS) and/or incomplete stent apposition (ISA) by intravascular ultrasound than in 12 VLST patients without PSS or ISA (10.6±6.1% versus 5.8±4.1%, P = 0.03). Evidences for fragments of atherosclerotic plaques in the aspirated thrombi were observed only in 3 (13%) out of 24 patients with DES VLST.

Conclusions

Eosinophil fraction in the aspirated thrombi was significantly higher in patients with DES VLST as compared with those with EST and LST. Evidences for fragments of atherosclerotic plaques were relatively uncommon in patients with DES VLST.  相似文献   
992.

Background

Idiopathic membranous nephropathy (IMN) is increasingly seen in older patients. However, differences in disease presentation and outcomes between older and younger IMN patients remain controversial. We compared patient characteristics between younger and older IMN patients.

Methods

We recruited 171 Japanese patients with IMN, including 90 (52.6%) patients <65 years old, 40 (23.4%) patients 65–70 years, and 41 (24.0%) patients ≥71 years. Clinical characteristics and outcomes were compared between younger and older IMN patients.

Results

During a median observation period of 37 months, 103 (60.2%) patients achieved complete proteinuria remission, which was not significantly associated with patient age (P = 0.831). However, 13 (7.6%) patients were hospitalized because of infection. Multivariate Cox proportional hazards models identified older age [adjusted hazard ratio (HR) = 3.11, 95% confidence interval (CI): 1.45–7.49, per 10 years; P = 0.003], prednisolone use (adjusted HR = 11.8, 95% CI: 1.59–242.5; P = 0.014), and cyclosporine used in combination with prednisolone (adjusted HR = 10.3, 95% CI: 1.59–204.4; P = 0.012) as significant predictors of infection. A <25% decrease in proteinuria at 1 month after immunosuppressive therapy initiation also predicted infection (adjusted HR = 6.72, 95% CI: 1.51–37.8; P = 0.012).

Conclusions

Younger and older IMN patients had similar renal outcomes. However, older patients were more likely to develop infection when using immunosuppressants. Patients with a poor response in the first month following the initiation of immunosuppressive therapy should be carefully monitored for infection and may require a faster prednisolone taper.  相似文献   
993.
Iguchi, J, Yamada, Y, Ando, S, Fujisawa, Y, Hojo, T, Nishimura, K, Kuzuhara, K, Yuasa, Y, and Ichihashi, N. Physical and performance characteristics of Japanese division 1 collegiate football players. J Strength Cond Res 25(12): 3368-3377, 2011-This study aimed to establish the physical and performance characteristics of football players in the Japanese Division 1 collegiate football program and perform a comparison of these characteristics between Japanese (n = 208) and US Division 1 football players (n = 797). The following comparisons were made: (a) between a higher-ranked university team vs. a lower-ranked university team in Japan, (b) between different playing positions in Japan, (c) between starters and nonstarters in Japan, and (d) between playing positions in Japan vs. those in the United States. The results of this study suggest that players in the higher-ranked university team were heavier, stronger in back squat, jumped higher, and had greater power than those on the lower-ranked team. Furthermore, linemen were generally characterized by larger size, greater strength, and more fat as compared with backs. On the other hand, backs tended to be faster, smaller in physical size, have higher vertical jump height, and show greater relative strength than linemen did. Starters were taller, heavier, stronger, had more powerful, and more fat-free mass than nonstarters. Finally, our results revealed that players in the United States were superior to players in Japan in all body status comparisons (p < 0.01). This study revealed that performance and superior body composition are essential for the success of a football player. Power and strength seem to be key factors in defining good football performance.  相似文献   
994.

Background  

DICER is an RNase III family endoribonuclease that processes precursor microRNAs (pre-miRNAs) and long double-stranded RNAs, generating microRNA (miRNA) duplexes and short interfering RNA duplexes with 20~23 nucleotides (nts) in length. The typical form of pre-miRNA processed by the Drosha protein is a hairpin RNA with 2-nt 3' overhangs. On the other hand, production of mature miRNA from an endogenous hairpin RNA with 5' overhangs has also been reported, although the mechanism for this process is unknown.  相似文献   
995.

Background

The release of cytochrome c from the mitochondria following cerebral ischemia is a key event leading to cell death. The goal of the present study was to determine the mechanisms involved in post-ischemic activation of protein kinase c delta (δPKC) that lead to cytochrome c release.

Methods/Findings

We used a rat model of cardiac arrest as an in vivo model, and an in vitro analog, oxygen glucose deprivation (OGD) in rat hippocampal synaptosomes. Cardiac arrest triggered translocation of δPKC to the mitochondrial fraction at 1 h reperfusion. In synaptosomes, the peptide inhibitor of δPKC blocked OGD-induced translocation to the mitochondria. We tested two potential pathways by which δPKC activation could lead to cytochrome c release: phosphorylation of phospholipid scramblase-3 (PLSCR3) and/or protein phosphatase 2A (PP2A). Cardiac arrest increased levels of phosphorlyated PLSCR3; however, inhibition of δPKC translocation failed to affect the OGD-induced increase in PLSCR3 in synaptosomal mitochondria suggesting the post-ischemic phosphorylation of PLSCR3 is not mediated by δPKC. Inhibition of either δPKC or PP2A decreased cytochrome c release from synaptosomal mitochondria. Cardiac arrest results in the dephosphorylation of Bad and Bax, both downstream targets of PP2A promoting apoptosis. Inhibition of δPKC or PP2A prevented OGD-induced Bad, but not Bax, dephosphorylation. To complement these studies, we used proteomics to identify novel mitochondrial substrates of δPKC.

Conclusions

We conclude that δPKC initiates cytochrome c release via phosphorylation of PP2A and subsequent dephosphorylation of Bad and identified δPKC, PP2A and additional mitochondrial proteins as potential therapeutic targets for ischemic neuroprotection.  相似文献   
996.
Human DICER1 protein cleaves double-stranded RNA into small sizes, a crucial step in production of single-stranded RNAs which are mediating factors of cytoplasmic RNA interference. Here, we clearly demonstrate that human DICER1 protein localizes not only to the cytoplasm but also to the nucleoplasm. We also find that human DICER1 protein associates with the NUP153 protein, one component of the nuclear pore complex. This association is detected predominantly in the cytoplasm but is also clearly distinguishable at the nuclear periphery. Additional characterization of the NUP153-DICER1 association suggests NUP153 plays a crucial role in the nuclear localization of the DICER1 protein.  相似文献   
997.
Synthetic proteo-nucleic structures (PDNAs) encompassing a single-stranded DNA sequence covalently attached to a redox protein domain able to interact with surface or matrix were designed and characterized. They constitute versatile building blocks alternative to regular DNA for creating scaffolds with optical, electrical, or catalytic properties. PDNAs self-assemble in the presence of complementary oligonucleotides, to form a network of protein domains linked by double-stranded DNA segments. Electrophoretic and hydrodynamic behaviors of PDNAs and corresponding DNA were compared under electrophoresis and gel filtration conditions. Hybridization rates between small and large assemblies were characterized by rapid-mixing experiments. Results showed that the protein part significantly contributes to hydrodynamic behaviors of structures but marginally affects the conformation and hybridization properties of the nucleic domain. PDNA metal-mediated complexes with nitriloacetate-modified phospholipids can diffuse and interact at the surface of vesicles or supported membranes. Surface plasmon resonance analysis of membrane-PDNA interactions indicated that two protein units are required to allow stable surface association and that surface occupancy constrains assembly sizes. High-speed atomic force microscopy illustrated rapid lateral diffusion of assemblies on mica, revealing transient association between noncomplementary PDNA extremities and frequent trapping by surface defects. Regularly organized protein domains were visualized using a larger DNA framework.  相似文献   
998.
The Seedling Ratio Method was devised to assess the impacts of introduced ungulates on plant species richness in forest understoreys. The method has successfully assessed ungulate impacts on species richness in forests in New Zealand and Hawaii, which do not have native herbivores. We tested the three critical assumptions that underlie this method to investigate its potential for use in an Australian ecosystem. This study was conducted in the Yarra Ranges National Park (YRNP), Victoria, which had a high‐density population of an introduced deer species, Sambar (Cervus unicolor), in addition to several native herbivore species. One of the three key assumptions of the Seedling Ratio Method was not supported, whereas conventional differential exclosures showed clear and separate impacts by Sambar and native herbivores. We conclude that the Seedling Ratio Method could not provide a clear indication of browsing impact on forest understoreys in YRNP.  相似文献   
999.
Uncovering population structure is important for properly conducting association studies and for examining the demographic history of a population. Here, we examined the Japanese population substructure using data from the Japan Multi-Institutional Collaborative Cohort (J-MICC), which covers all but the northern region of Japan. Using 222 autosomal loci from 4502 subjects, we investigated population substructure by estimating F(ST) among populations, testing population differentiation, and performing principal component analysis (PCA) and correspondence analysis (CA). All analyses revealed a low but significant differentiation between the Amami Islanders and the mainland Japanese population. Furthermore, we examined the genetic differentiation between the mainland population, Amami Islanders and Okinawa Islanders using six loci included in both the Pan-Asian SNP (PASNP) consortium data and the J-MICC data. This analysis revealed that the Amami and Okinawa Islanders were differentiated from the mainland population. In conclusion, we revealed a low but significant level of genetic differentiation between the mainland population and populations in or to the south of the Amami Islands, although genetic variation between both populations might be clinal. Therefore, the possibility of population stratification must be considered when enrolling the islander population of this area, such as in the J-MICC study.  相似文献   
1000.

Background

Inflammatory bowel disease (IBD) is a chronic intestinal disorder that is associated with a limited number of clinical biomarkers. In order to facilitate the diagnosis of IBD and assess its disease activity, we investigated the potential of novel multivariate indexes using statistical modeling of plasma amino acid concentrations (aminogram).

Methodology and Principal Findings

We measured fasting plasma aminograms in 387 IBD patients (Crohn''s disease (CD), n = 165; ulcerative colitis (UC), n = 222) and 210 healthy controls. Based on Fisher linear classifiers, multivariate indexes were developed from the aminogram in discovery samples (CD, n = 102; UC, n = 102; age and sex-matched healthy controls, n = 102) and internally validated. The indexes were used to discriminate between CD or UC patients and healthy controls, as well as between patients with active disease and those in remission. We assessed index performances using the area under the curve of the receiver operating characteristic (ROC AUC). We observed significant alterations to the plasma aminogram, including histidine and tryptophan. The multivariate indexes established from plasma aminograms were able to distinguish CD or UC patients from healthy controls with ROC AUCs of 0.940 (95% confidence interval (CI): 0.898–0.983) and 0.894 (95%CI: 0.853–0.935), respectively in validation samples (CD, n = 63; UC, n = 120; healthy controls, n = 108). In addition, other indexes appeared to be a measure of disease activity. These indexes distinguished active CD or UC patients from each remission patients with ROC AUCs of 0.894 (95%CI: 0.853–0.935) and 0.849 (95%CI: 0.770–0.928), and correlated with clinical disease activity indexes for CD (rs = 0.592, 95%CI: 0.385–0.742, p<0.001) or UC (rs = 0.598, 95%CI: 0.452–0.713, p<0.001), respectively.

Conclusions and Significance

In this study, we demonstrated that established multivariate indexes composed of plasma amino acid profiles can serve as novel, non-invasive, objective biomarkers for the diagnosis and monitoring of IBD, providing us with new insights into the pathophysiology of the disease.  相似文献   
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