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81.
Chronic inflammatory diseases, such as rheumatoid arthritis and periodontitis-caused bone destruction, results from an increase of bone-resorbing osteoclasts (OCs) induced by inflammation. However, the detailed mechanisms underlying this disorder remain unclear. We herein investigated that the effect of urokinase-type plasminogen activator (uPA) on inflammatory osteoclastogenesis induced by lipopolysaccharide (LPS), which is a potent stimulator of bone resorption in inflammatory diseases. We found that the uPA deficiency promoted inflammatory osteoclastogenesis and bone loss induced by LPS. We also showed that LPS induced the expression of uPA, and the uPA treatment attenuated the LPS-induced inflammatory osteoclastogenesis of RAW264.7 mouse monocyte/macrophage lineage cells. Additionally, we showed that the uPA-attenuated inflammatory osteoclastgenesis is associated with the activation of plasmin/protease-activated receptor (PAR)-1 axis by uPA. Moreover, we examined the mechanism underlying the effect of uPA on inflammatory osteoclastogenesis, and found that uPA/plasmin/PAR-1 activated the adenosine monophosphate-activated protein kinase (AMPK) pathway through Ca2+/calmodulin dependent protein kinase kinase (CaMKK) activation, and attenuated inflammatory osteoclastogenesis by inactivation of NF-κB in RAW264.7 cells. These data suggest that uPA attenuated inflammatory osteoclastogenesis through the plasmin/PAR-1/Ca2+/CaMKK/AMPK axis. Our findings may provide a novel therapeutic approach to bone loss caused by inflammatory diseases.  相似文献   
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Artificial RING fingers (ARFs) are created by transplanting active sites of RING fingers onto cross‐brace structures. Human hydroxymethylglutaryl‐coenzyme A reductase degradation protein 1 (HRD1) is involved in the degradation of the endoplasmic reticulum (ER) proteins. HRD1 possesses the RING finger domain (HRD1_RING) that functions as a ubiquitin‐ligating (E3) enzyme. Herein, we determined the solution structure of HRD1_RING using nuclear magnetic resonance (NMR). Moreover, using a metallochromic indicator, we determined the stoichiometry of zinc ions spectrophotometrically and found that HRD1_RING binds to two zinc atoms. The Simple Modular Architecture Research Tool database predicted the structure of HRD1_RING as a typical RING finger. However, it was found that the actual structure of HRD1_RING adopts an atypical RING‐H2 type RING fold. This structural analysis unveiled the position and range of the active site of HRD1_RING that contribute to its specific ubiquitin‐conjugating enzyme (E2)‐binding capability.  相似文献   
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Probiotics and Antimicrobial Proteins - Probiotic-rich foods are consumed without much restriction. We report here, a case of septic shock caused by yogurt derived Lactobacillus species in a...  相似文献   
86.
Forest Structure and Primary Productivity in a Bornean Heath Forest   总被引:2,自引:0,他引:2  
Aboveground forest structure, biomass, and primary productivity in a tropical heath forest in Central Kalimantan (Indonesian Borneo) were examined using data from 1-ha plots and stand-level allometric equations developed from harvested tree samples. The study site experienced a severe drought in 1997–1998 associated with the El Niño Southern Oscillation event. The drought effect on heath forest productivity was also assessed by evaluating changes in wood mass increment rates. Allometric relationships suggested that heath forest trees had leaves with smaller specific leaf area (SLA), and large heath forest trees allocate more to leaf mass compared to mixed dipterocarp forest trees. Aboveground biomass (for trees ≥ 4.8 cm DBH) in two 1-ha plots, P1 and P4, totaled 244.8 and 232.0 Mg/ha. Aboveground wood mass increment rate was –0.1 and 4.7 Mg/ha/yr in P1 and P4 during the drought period (from February to August 1998), while it quickly recovered to 8.1 and 8.5 Mg/ha/yr during the post-drought period (from August 1998 to August 1999 for P1 and from August 1998 to November 1999 for P4). This suggests a severe impact of the drought on heath forest productivity. Leaf characteristics of heath forest such as small SLA and long-lived leaves probably play a significant role in effective assimilation and maintenance of heath forest productivity under stressful conditions.  相似文献   
87.
Knudsen B  Miyamoto MM 《Genetics》2007,176(4):2335-2342
Coalescent theory provides a powerful framework for estimating the evolutionary, demographic, and genetic parameters of a population from a small sample of individuals. Current coalescent models have largely focused on population genetic factors (e.g., mutation, population growth, and migration) rather than on the effects of experimental design and error. This study develops a new coalescent/mutation model that accounts for unobserved polymorphisms due to missing data, sequence errors, and multiple reads for diploid individuals. The importance of accommodating these effects of experimental design and error is illustrated with evolutionary simulations and a real data set from a population of the California sea hare. In particular, a failure to account for sequence errors can lead to overestimated mutation rates, inflated coalescent times, and inappropriate conclusions about the population. This current model can now serve as a starting point for the development of newer models with additional experimental and population genetic factors. It is currently implemented as a maximum-likelihood method, but this model may also serve as the basis for the development of Bayesian approaches that incorporate experimental design and error.  相似文献   
88.
Although cullin-1 neddylation is crucial for the activation of SCF ubiquitin E3 ligases, the underlying mechanisms for NEDD8-mediated activation of SCF remain unclear. Here we demonstrate by NMR and mutational studies that NEDD8 binds the ubiquitin E2 (UBC4), but not NEDD8 E2 (UBC12). Our data imply that NEDD8 forms an active platform on the SCF complex for selective recruitment of ubiquitin-charged E2s in collaboration with RBX1, and thereby upregulates the E3 activity.  相似文献   
89.
Primary neuroendocrine neoplasm of the liver is extremely rare in both humans and non‐human primates. The present report describes the clinical and pathological findings of an aged Japanese macaque (Macaca fuscata) with hepatic neuroendocrine carcinoma. To our knowledge, this is the first report of hepatic neuroendocrine neoplasm in macaques.  相似文献   
90.
Prior studies have revealed that the sympathetic nervous system regulates the clinical and pathological manifestations of experimental autoimmune encephalomyelitis (EAE), an autoimmune disease model mediated by Th1 T cells. Although the regulatory role of catecholamines has been indicated in the previous works, it remained possible that other sympathetic neurotransmitters like neuropeptide Y (NPY) may also be involved in the regulation of EAE. Here we examined the effect of NPY and NPY receptor subtype-specific compounds on EAE, actively induced with myelin oligodendrocyte glycoprotein 35-55 in C57BL/6 mice. Our results revealed that exogenous NPY as well as NPY Y(1) receptor agonists significantly inhibited the induction of EAE, whereas a Y(5) receptor agonist or a combined treatment of NPY with a Y(1) receptor antagonist did not inhibit signs of EAE. These results indicate that the suppression of EAE by NPY is mediated via Y(1) receptors. Furthermore, treatment with the Y(1) receptor antagonist induced a significantly earlier onset of EAE, indicating a protective role of endogenous NPY in the induction phase of EAE. We also revealed a significant inhibition of myelin oligodendrocyte glycoprotein 35-55-specific Th1 response as well as a Th2 bias of the autoimmune T cells in mice treated with the Y(1) receptor agonist. Ex vivo analysis further demonstrated that autoimmune T cells are directly affected by NPY via Y(1) receptors. Taken together, we conclude that NPY is a potent immunomodulator involved in the regulation of the Th1-mediated autoimmune disease EAE.  相似文献   
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