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991.

Objective

To understand and predict chronic obstructive pulmonary disease (COPD), a biomarker that reflects disease severity is needed.

Research Design and Methods

Data from 10269 adults aged over 40 years of age were retrieved from the Korea National Health and Nutrition Examination Survey (KNHANES), and 1302 patients met the criteria for COPD. The association between values of vitamin D and parathyroid hormone (PTH), and COPD severity including lung function and quality of life, were analyzed.

Results

In COPD patients, lung function was inversely related to PTH values (P = 0.02 for FVC [% predicted]; P < 0.001 for FEV1 [% predicted]); however, the association of lung function with vitamin D levels was not statistically significant in a multivariable analysis. Value of PTH was independently associated with EQ5D-index (P = 0.04), but vitamin D level showed no significant relationship with EQ5D-index (P = 0.59) or EQ5D-VAS (P = 0.81).

Conclusions

Elevation of PTH, unlike vitamin D, is independently associated with COPD severity, and may be a better biomarker for COPD.  相似文献   
992.
Earlier research has revealed that the ndh loci have been pseudogenized, truncated, or deleted from most orchid plastomes sequenced to date, including in all available plastomes of the two most species-rich subfamilies, Orchidoideae and Epidendroideae. This study sought to resolve deeper-level phylogenetic relationships among major orchid groups and to refine the history of gene loss in the ndh loci across orchids. The complete plastomes of seven orchids, Oncidium sphacelatum (Epidendroideae), Masdevallia coccinea (Epidendroideae), Sobralia callosa (Epidendroideae), Sobralia aff. bouchei (Epidendroideae), Elleanthus sodiroi (Epidendroideae), Paphiopedilum armeniacum (Cypripedioideae), and Phragmipedium longifolium (Cypripedioideae) were sequenced and analyzed in conjunction with all other available orchid and monocot plastomes. Most ndh loci were found to be pseudogenized or lost in Oncidium, Paphiopedilum and Phragmipedium, but surprisingly, all ndh loci were found to retain full, intact reading frames in Sobralia, Elleanthus and Masdevallia. Character mapping suggests that the ndh genes were present in the common ancestor of orchids but have experienced independent, significant losses at least eight times across four subfamilies. In addition, ndhF gene loss was correlated with shifts in the position of the junction of the inverted repeat (IR) and small single-copy (SSC) regions. The Orchidaceae have unprecedented levels of homoplasy in ndh gene presence/absence, which may be correlated in part with the unusual life history of orchids. These results also suggest that ndhF plays a role in IR/SSC junction stability.  相似文献   
993.
Mad2, a key component of the spindle checkpoint, is closely associated with chromosomal instability and poor prognosis in cancer. p31comet is a Mad2-interacting protein that serves as a spindle checkpoint silencer at mitosis. In this study, we showed that p31comet-induced apoptosis and senescence occur via counteraction of Mad2 activity. Upon retroviral transduction of p31comet, the majority of human cancer cell lines tested lost the ability to form colonies in a low-density seeding assay. Cancer cells with p31comet overexpression underwent distinct apoptosis and/or senescence, irrespective of p53 status, confirming the cytotoxicity of p31comet. Interestingly, both cytotoxic and Mad2 binding activities were eliminated upon deletion of the C-terminal 30 amino acids of p31comet. Point mutation or deletion of the region affecting Mad2 binding additionally abolished cytotoxic activity. Consistently, wild-type Mad2 interacting with p31comet, but not its non-binding mutant, inhibited cell death, indicating that the mechanism of p31comet-induced cell death involves Mad2 inactivation. Our results clearly suggest that the regions of p31comet affecting interactions with Mad2, including the C-terminus, are essential for induction of cell death. The finding that p31comet-induced cell death is mediated by interactions with Mad2 that lead to its inactivation is potentially applicable in anticancer therapy.  相似文献   
994.
995.
Astrocytes play an active role in the modulation of synaptic transmission by releasing cell-cell signaling molecules in response to various stimuli that evoke a Ca(2+) increase. We expand on recent studies of astrocyte intracellular and secreted proteins by examining the astrocyte peptidome in mouse astrocytic cell lines and rat primary cultured astrocytes, as well as those peptides secreted from mouse astrocytic cell lines in response to Ca(2+)-dependent stimulations. We identified 57 peptides derived from 24 proteins with LC-MS/MS and CE-MS/MS in the astrocytes. Among the secreted peptides, four peptides derived from elongation factor 1, macrophage migration inhibitory factor, peroxiredoxin-5, and galectin-1 were putatively identified by mass-matching to peptides confirmed to be found in astrocytes. Other peptides in the secretion study were mass-matched to those found in prior peptidomics analyses on mouse brain tissue. Complex peptide profiles were observed after stimulation, suggesting that astrocytes are actively involved in peptide secretion. Twenty-six peptides were observed in multiple stimulation experiments but not in controls and thus appear to be released in a Ca(2+)-dependent manner. These results can be used in future investigations to better understand stimulus-dependent mechanisms of astrocyte peptide secretion.  相似文献   
996.
Mesenchymal stem cells (MSCs) have emerged as a promising means for treating degenerative or incurable diseases. Recent studies have shown that microvesicles (MVs) from MSCs (MSC-MVs) contribute to recovery of damaged tissues in animal disease models. Here, we profiled the MSC-MV proteome to investigate their therapeutic effects. LC-MS/MS analysis of MSC-MVs identified 730 MV proteins. The MSC-MV proteome included five positive and two variable known markers of MSCs, but no negative marker, as well as 43 surface receptors and signaling molecules controlling self-renewal and differentiation of MSCs. Functional enrichment analysis showed that cellular processes represented by the MSC-MV proteins include cell proliferation, adhesion, migration, and morphogenesis. Integration of MSC's self-renewal and differentiation-related genes and the proteome of MSC-conditioned media (MSC-CM) with the MSC-MV proteome revealed potential MV protein candidates that can be associated with the therapeutic effects of MSC-MVs: (1) surface receptors (PDGFRB, EGFR, and PLAUR); (2) signaling molecules (RRAS/NRAS, MAPK1, GNA13/GNG12, CDC42, and VAV2); (3) cell adhesion (FN1, EZR, IQGAP1, CD47, integrins, and LGALS1/LGALS3); and (4) MSC-associated antigens (CD9, CD63, CD81, CD109, CD151, CD248, and CD276). Therefore, the MSC-MV proteome provides a comprehensive basis for understanding the potential of MSC-MVs to affect tissue repair and regeneration.  相似文献   
997.
Peroxidation of cardiolipin in mitochondria is essential for the execution of apoptosis. We suggested that integration of oleic acid into cardiolipin generates non-oxidizable cardiolipin species hence protects cells against apoptosis. We synthesized mitochondria-targeted triphenylphosphonium oleic acid ester. Using lipidomics analysis we found that pretreatment of mouse embryonic cells with triphenylphosphonium oleic acid ester resulted in decreased contents of polyunsaturated cardiolipins and elevation of its species containing oleic acid residues. This caused suppression of apoptosis induced by actinomycin D. Triacsin C, an inhibitor of acyl-CoA synthase, blocked integration of oleic acid into cardiolipin and restored cell sensitivity to apoptosis.  相似文献   
998.
Radiation and Environmental Biophysics - The article Dose–responses for mortality from cerebrovascular and heart diseases in atomic bomb survivors: 1950–2003, written by Helmut...  相似文献   
999.
Recent studies have highlighted that early enhancement of the glycolytic pathway is a mode of maintaining the pro-inflammatory status of immune cells. Thiamine, a well-known co-activator of pyruvate dehydrogenase complex, a gatekeeping enzyme, shifts energy utilization of glucose from glycolysis to oxidative phosphorylation. Thus, we hypothesized that thiamine may modulate inflammation by alleviating metabolic shifts during immune cell activation. First, using allithiamine, which showed the most potent anti-inflammatory capacity among thiamine derivatives, we confirmed the inhibitory effects of allithiamine on the lipopolysaccharide (LPS)-induced pro-inflammatory cytokine production and maturation process in dendritic cells. We applied the LPS-induced sepsis model to examine whether allithiamine has a protective role in hyper-inflammatory status. We observed that allithiamine attenuated tissue damage and organ dysfunction during endotoxemia, even when the treatment was given after the early cytokine release. We assessed the changes in glucose metabolites during LPS-induced dendritic cell activation and found that allithiamine significantly inhibited glucose-driven citrate accumulation. We then examined the clinical implication of regulating metabolites during sepsis by performing a tail bleeding assay upon allithiamine treatment, which expands its capacity to hamper the coagulation process. Finally, we confirmed that the role of allithiamine in metabolic regulation is critical in exerting anti-inflammatory action by demonstrating its inhibitory effect upon mitochondrial citrate transporter activity. In conclusion, thiamine could be used as an alternative approach for controlling the immune response in patients with sepsis.  相似文献   
1000.
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