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排序方式: 共有212条查询结果,搜索用时 251 毫秒
61.
Elisabeth APM Romme David A McAllister John T Murchison Edwin JR Van Beek George S Petrides Cameron OS Price Erica PA Rutten Frank WJM Smeenk Emiel FM Wouters William MacNee 《Respiratory research》2013,14(1):129
Background
Cardiovascular disease, osteoporosis and emphysema are associated with COPD. Associations between these factors and whether they predict all-cause mortality in COPD patients are not well understood. Therefore, we examined associations between markers of cardiovascular disease (coronary artery calcification [CAC], thoracic aortic calcification [TAC] and arterial stiffness), bone density (bone attenuation of the thoracic vertebrae), emphysema (PI-950 and 15th percentile) and all-cause mortality in a COPD cohort.Methods
We assessed CAC, TAC, bone attenuation of the thoracic vertebrae, PI-950 and 15th percentile on low-dose chest computed tomography in COPD subjects. We measured arterial stiffness as carotid-radial pulse wave velocity (PWV), and identified deaths from the national register.Results
We studied 119 COPD subjects; aged 67.8 ±7.3, 66% were males and mean FEV1% predicted was 46.0 ±17.5. Subjects were classified into three pre-specificed groups: CAC = 0 (n = 14), 0 < CAC ≤ 400 (n = 41) and CAC > 400 (n = 64). Subjects with higher CAC were more likely to be older (p < 0.001) and male (p = 0.03), and more likely to have higher systolic blood pressure (p = 0.001) and a history of hypertension (p = 0.002) or ischemic heart disease (p = 0.003). Higher CAC was associated with higher PWV (OR 1.62, p = 0.04) and lower bone attenuation (OR 0.32, p = 0.02), but not with 15th percentile, after adjustment for age, sex and pack-years of smoking. In a Cox proportional hazards model, CAC, TAC and 15th percentile predicted all-cause mortality (HR 2.01, 2.09 and 0.66, respectively).Conclusions
Increased CAC was associated with increased arterial stiffness and lower bone density in a COPD cohort. In addition, CAC, TAC and extent of emphysema predicted all-cause mortality.Trial registration
Lothian NHS Board, Lothian Research Ethics Committee, LREC/2003/8/28. 相似文献62.
63.
Lee BY Assi TM Rookkapan K Wateska AR Rajgopal J Sornsrivichai V Chen SI Brown ST Welling J Norman BA Connor DL Bailey RR Jana A Van Panhuis WG Burke DS 《PloS one》2011,6(9):e24673
Although the substantial burdens of rotavirus and pneumococcal disease have motivated many countries to consider introducing the rotavirus vaccine (RV) and heptavalent pneumococcal conjugate vaccine (PCV-7) to their National Immunization Programs (EPIs), these new vaccines could affect the countries' vaccine supply chains (i.e., the series of steps required to get a vaccine from their manufacturers to patients). We developed detailed computational models of the Trang Province, Thailand, vaccine supply chain to simulate introducing various RV and PCV-7 vaccine presentations and their combinations. Our results showed that the volumes of these new vaccines in addition to current routine vaccines could meet and even exceed (1) the refrigerator space at the provincial district and sub-district levels and (2) the transport cold space at district and sub-district levels preventing other vaccines from being available to patients who arrive to be immunized. Besides the smallest RV presentation (17.1 cm3/dose), all other vaccine introduction scenarios required added storage capacity at the provincial level (range: 20 L-1151 L per month) for the three largest formulations, and district level (range: 1 L-124 L per month) across all introduction scenarios. Similarly, with the exception of the two smallest RV presentation (17.1 cm3/dose), added transport capacity was required at both district and sub-district levels. Added transport capacity required across introduction scenarios from the provincial to district levels ranged from 1 L-187 L, and district to sub-district levels ranged from 1 L-13 L per shipment. Finally, only the smallest RV vaccine presentation (17.1 cm3/dose) had no appreciable effect on vaccine availability at sub-districts. All other RV and PCV-7 vaccines were too large for the current supply chain to handle without modifications such as increasing storage or transport capacity. Introducing these new vaccines to Thailand could have dynamic effects on the availability of all vaccines that may not be initially apparent to decision-makers. 相似文献
64.
Milena Bellin Simona Casini Richard P Davis Cristina D'Aniello Jessica Haas Dorien Ward‐van Oostwaard Leon G J Tertoolen Christian B Jung David A Elliott Andrea Welling Karl‐Ludwig Laugwitz Alessandra Moretti Christine L Mummery 《The EMBO journal》2013,32(24):3161-3175
Patient‐specific induced pluripotent stem cells (iPSCs) will assist research on genetic cardiac maladies if the disease phenotype is recapitulated in vitro. However, genetic background variations may confound disease traits, especially for disorders with incomplete penetrance, such as long‐QT syndromes (LQTS). To study the LQT2‐associated c.A2987T (N996I) KCNH2 mutation under genetically defined conditions, we derived iPSCs from a patient carrying this mutation and corrected it. Furthermore, we introduced the same point mutation in human embryonic stem cells (hESCs), generating two genetically distinct isogenic pairs of LQTS and control lines. Correction of the mutation normalized the current (IKr) conducted by the HERG channel and the action potential (AP) duration in iPSC‐derived cardiomyocytes (CMs). Introduction of the same mutation reduced IKr and prolonged the AP duration in hESC‐derived CMs. Further characterization of N996I‐HERG pathogenesis revealed a trafficking defect. Our results demonstrated that the c.A2987T KCNH2 mutation is the primary cause of the LQTS phenotype. Precise genetic modification of pluripotent stem cells provided a physiologically and functionally relevant human cellular context to reveal the pathogenic mechanism underlying this specific disease phenotype. 相似文献
65.
Systems Biology involves the study of the interactions of biological systems and ultimately their functions. Down''s syndrome (DS)
is one of the most common genetic disorders which are caused by complete, or occasionally partial, triplication of chromosome 21,
characterized by cognitive and language dysfunction coupled with sensory and neuromotor deficits. Neural Tube Disorders
(NTDs) are a group of congenital malformations of the central nervous system and neighboring structures related to defective
neural tube closure during the first trimester of pregnancy usually occurring between days 18-29 of gestation. Several studies in the
past have provided considerable evidence that abnormal folate and methyl metabolism are associated with onset of DS & NTDs.
There is a possible common etiological pathway for both NTDs and Down''s syndrome. But, various research studies over the years
have indicated very little evidence for familial link between the two disorders. Our research aimed at the gene expression profiling
of microarray datasets pertaining to the two disorders to identify genes whose expression levels are significantly altered in these
conditions. The genes which were 1.5 fold unregulated and having a p-value <0.05 were filtered out and gene interaction network
were constructed for both NTDs and DS. The top ranked dense clique for both the disorders were recognized and over
representation analysis was carried out for each of the constituent genes. The comprehensive manual analysis of these genes yields
a hypothetical understanding of the lack of familial link between DS and NTDs. There were no genes involved with folic acid
present in the dense cliques. Only – CBL, EGFR genes were commonly present, which makes the allelic variants of these genes –
good candidates for future studies regarding the familial link between DS and NTDs.
Abbreviations
NTD - Neural Tube Disorders, DS - Down''s Syndrome, MTHFR - Methylenetetrahydrofolate reductase, MTRR– 5 - methyltetrahydrofolate-homocysteine methyltransferase reductase. 相似文献66.
67.
Nicolas Markadieu Kerri Rios Benjamin W. Spiller W. Hayes McDonald Paul A. Welling Eric Delpire 《The Journal of biological chemistry》2014,289(42):29273-29284
The Ste20-related kinase SPAK regulates sodium, potassium, and chloride transport in a variety of tissues. Recently, SPAK fragments, which lack the catalytic domain and are inhibitory to Na+ transporters, have been detected in kidney. It has been hypothesized that the fragments originate from alternative translation start sites, but their precise origin is unknown. Here, we demonstrate that kidney lysate possesses proteolytic cleavage activity toward SPAK. Ion exchange and size exclusion chromatography combined with mass spectrometry identified the protease as aspartyl aminopeptidase. The presence of the protease was verified in the active fractions, and recombinant aspartyl aminopeptidase recapitulated the cleavage pattern observed with kidney lysate. Identification of the sites of cleavage by mass spectrometry allowed us to test the function of the smaller fragments and demonstrate their inhibitory action toward the Na+-K+-2Cl− cotransporter, NKCC2. 相似文献
68.
Kryczek I Bruce AT Gudjonsson JE Johnston A Aphale A Vatan L Szeliga W Wang Y Liu Y Welling TH Elder JT Zou W 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(7):4733-4741
Th1 and Th17 T cells are often colocalized in pathological environments, yet Th1-derived IFN-gamma inhibits Th17 cell development in vitro. We explored the physiologic basis of this paradox in humans. In this study, we demonstrate increased the number of CD4(+) and CD8(+) IL-17(+) T cells in skin lesions of psoriasis. Furthermore, we show that myeloid APCs potently support induction of IL-17(+) T cells, and that this activity is greatly increased in psoriasis. We tested stimuli that might account for this activity. Th1 cells and IFN-gamma are increased in psoriatic blood and lesional skin. We show that IFN-gamma programs myeloid APCs to induce human IL-17(+) T cells via IL-1 and IL-23. IFN-gamma also stimulates APC production of CCL20, supporting migration of IL-17(+) T cells, and synergizes with IL-17 in the production of human beta-defensin 2, an antimicrobial and chemotactic protein highly overexpressed by psoriatic keratinocytes. This study reveals a novel mechanistic interaction between Th1 and IL-17(+) T cells, challenges the view that Th1 cells suppress Th17 development through IFN-gamma, and suggests that Th1 and IL-17(+) T cells may collaboratively contribute to human autoimmune diseases. 相似文献
69.
70.
Effects of Alternative Dietary Substrates on Competition between Human Colonic Bacteria in an Anaerobic Fermentor System 总被引:10,自引:5,他引:5
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Sylvia H. Duncan Karen P. Scott Alan G. Ramsay Hermie J. M. Harmsen Gjalt W. Welling Colin S. Stewart Harry J. Flint 《Applied microbiology》2003,69(2):1136-1142
Duplicate anaerobic fermentor systems were used to examine changes in a community of human fecal bacteria supplied with different carbohydrate energy sources. A panel of group-specific fluorescent in situ hybridization probes targeting 16S rRNA sequences revealed that the fermentors supported growth of a greater proportion of Bacteroides and a lower proportion of gram-positive anaerobes related to Faecalibacterium prausnitzii, Ruminococcus flavefaciens-Ruminococcus bromii, Eubacterium rectale-Clostridium coccoides, and Eubacterium cylindroides than the proportions in the starting fecal inoculum. Nevertheless, certain substrates, such as dahlia inulin, caused a pronounced increase in the number of bacteria related to R. flavefaciens-R. bromii and E. cylindroides. The ability of three strictly anaerobic, gram-positive bacteria to compete with the complete human fecal flora was tested in the same experiment by using selective plating to enumerate the introduced strains. The Roseburia-related strain A2-183F was able to grow on all substrates despite the fact that it was unable to utilize complex carbohydrates in pure culture, and it was assumed that this organism survived by cross-feeding. In contrast, Roseburia intestinalis L1-82R and Eubacterium sp. strain A2-194R survived less well despite the fact that they were able to utilize polysaccharides in pure culture, except that A2-194R was stimulated 100-fold by inulin. These results suggest that many low-G+C-content gram-positive obligate anaerobes may be selected against during in vitro incubation, although several groups were stimulated by inulin. Thus, considerable caution is necessary when workers attempt to predict the in vivo effects of probiotics and prebiotics from their effects in vitro. 相似文献