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991.
992.
Kim Beernaert Luc Deliens Koen Pardon Lieve Van den Block Dirk Devroey Kenneth Chambaere Joachim Cohen 《PloS one》2015,10(9)
Background
Many people who might benefit from specialist palliative care services are not using them.Aim
We examined the use of these services and the reasons for not using them in a population in potential need of palliative care.Methods
We conducted a population-based survey regarding end-of-life care among physicians certifying a large representative sample (n = 6188) of deaths in Flanders, Belgium.Results
Palliative care services were not used in 79% of cases of people with organ failure, 64% of dementia and 44% of cancer. The most frequently indicated reasons were that 1) existing care already sufficiently addressed palliative and supportive needs (56%), 2) palliative care was not deemed meaningful (26%) and 3) there was insufficient time to initiate palliative care (24%). The reasons differed according to patient characteristics: in people with dementia the consideration of palliative care as not meaningful was more likely to be a reason for not using it; in older people their care needs already being sufficiently addressed was more likely to be a reason. For those patients who were referred the timing of referral varied from a median of six days before death (organ failure) to 16 days (cancer).Conclusions
Specialist palliative care is not initiated in almost half of the people for whom it could be beneficial, most frequently because physicians deem regular caregivers to be sufficiently skilled in addressing palliative care needs. This would imply that the safeguarding of palliative care skills in this regular ‘general’ care is an essential health policy priority. 相似文献993.
994.
Kenneth C. Catania 《PloS one》2010,5(6)
Background
Aquatic tentacled snakes (Erpeton tentaculatus) can take advantage of their prey''s escape response by startling fish with their body before striking. The feint usually startles fish toward the snake''s approaching jaws. But when fish are oriented at a right angle to the jaws, the C-start escape response translates fish parallel to the snake''s head. To exploit this latter response, snakes must predict the future location of the fish. Adult snakes can make this prediction. Is it learned, or are tentacled snakes born able to predict future fish behavior?Methods and Findings
Laboratory-born, naïve snakes were investigated as they struck at fish. Trials were recorded at 250 or 500 frames per second. To prevent learning, snakes were placed in a water container with a clear transparency sheet or glass bottom. The chamber was placed over a channel in a separate aquarium with fish below. Thus snakes could see and strike at fish, without contact. The snake''s body feint elicited C-starts in the fish below the transparency sheet, allowing strike accuracy to be quantified in relationship to the C-starts. When fish were oriented at a right angle to the jaws, naïve snakes biased their strikes to the future location of the escaping fish''s head, such that the snake''s jaws and the fish''s translating head usually converged. Several different types of predictive strikes were observed.Conclusions
The results show that some predators have adapted their nervous systems to directly compensate for the future behavior of prey in a sensory realm that usually requires learning. Instead of behavior selected during their lifetime, newborn tentacled snakes exhibit behavior that has been selected on a different scale—over many generations. Counter adaptations in fish are not expected, as tentacled snakes are rare predators exploiting fish responses that are usually adaptive. 相似文献995.
J?rgen Gravning Stein ?rn Ole J?rgen Kaasb?ll Vladimir N. Martinov Cord Manhenke Kenneth Dickstein Thor Edvardsen H?vard Attramadal Mohammed Shakil Ahmed 《PloS one》2012,7(12)
Aims
Myocardial CCN2/CTGF is induced in heart failure of various etiologies. However, its role in the pathophysiology of left ventricular (LV) remodeling after myocardial infarction (MI) remains unresolved. The current study explores the role of CTGF in infarct healing and LV remodeling in an animal model and in patients admitted for acute ST-elevation MI.Methods and Results
Transgenic mice with cardiac-restricted overexpression of CTGF (Tg-CTGF) and non-transgenic littermate controls (NLC) were subjected to permanent ligation of the left anterior descending coronary artery. Despite similar infarct size (area of infarction relative to area at risk) 24 hours after ligation of the coronary artery in Tg-CTGF and NLC mice, Tg-CTGF mice disclosed smaller area of scar tissue, smaller increase of cardiac hypertrophy, and less LV dilatation and deterioration of LV function 4 weeks after MI. Tg-CTGF mice also revealed substantially reduced mortality after MI. Remote/peri-infarct tissue of Tg-CTGF mice contained reduced numbers of leucocytes, macrophages, and cells undergoing apoptosis as compared with NLC mice. In a cohort of patients with acute ST-elevation MI (n = 42) admitted to hospital for percutaneous coronary intervention (PCI) serum-CTGF levels (s-CTGF) were monitored and related to infarct size and LV function assessed by cardiac MRI. Increase in s-CTGF levels after MI was associated with reduced infarct size and improved LV ejection fraction one year after MI, as well as attenuated levels of CRP and GDF-15.Conclusion
Increased myocardial CTGF activities after MI are associated with attenuation of LV remodeling and improved LV function mediated by attenuation of inflammatory responses and inhibition of apoptosis. 相似文献996.
Simin Feng Zhuqing Dai Anna B. Liu Jinbao Huang Nihal Narsipur Grace Guo Bo Kong Kenneth Reuhl Wenyun Lu Zisheng Luo Chung S. Yang 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2018,1863(10):1274-1284
Objective
To investigate and compare the effects of two common dietary phytosterols, stigmasterol and β-sitosterol, in altering lipid metabolism and attenuating nonalcoholic fatty liver disease (NAFLD).Methods
Stigmasterol and β-sitosterol were administered to mice at 0.4% in a high-fat western-style diet (HFWD) for 17?weeks.Results
Stigmasterol and β-sitosterol significantly ameliorated HFWD-induced fatty liver and metabolic abnormalities, including elevated levels of hepatic total lipids, triacylglycerols, cholesterol and liver histopathology. Both phytosterols decreased the levels of intestinal bile acids, accompanied by markedly increased fecal lipid levels. In addition, they altered the expression of genes involved in lipid metabolism. β-Sitosterol was less effective in affecting most of these parameters. Lipidomic analysis of liver and serum samples showed that stigmasterol prevented the HFWD-induced elevation of some di- and triacylglycerol species and lowering of some phospholipid species. Stigmasterol also decreased serum levels of ceramides.Conclusion
Stigmasterol and β-sitosterol, at a dose corresponding to that suggested for humans by the FDA for lowering cholesterol levels, are shown to alleviate HFWD-induced NAFLD. Stigmasterol was more effective than β-sitosterol, possibly because of its suppression of hepatic lipogenic gene expression and modulation of circulating ceramide levels. 相似文献997.
Although cortical nonmuscle myosin II has long been implicated in cytokinetic aspects of cell division, there has never been strong evidence that it plays a role in the organization of the mitotic spindle. ([this issue of Cell]) use a number of methods to show that cortical myosin II is in fact important for spindle assembly in higher eukaryotic cells, specifically for the complete separation of centrosomes after nuclear envelope breakdown. 相似文献
998.
The catalytic subunit of cAMP-dependent protein kinase (cAPK) is susceptible to inactivation by a number of thiol-modifying reagents. Inactivation occurs through modification of cysteine 199, which is located near the active site. Because cysteine 199 is reactive at physiological pH, and modification of this site inhibits activity, we hypothesized that cAPK is a likely target for regulation by an oxidative mechanism, specifically glutathionylation. In vitro studies demonstrated the susceptibility of kinase activity to the sulfhydryl oxidant diamide, which inhibited by promoting an intramolecular disulfide bond between cysteines 199 and 343. In the presence of a low concentration of diamide and reduced glutathione, the kinase was rapidly and reversibly inhibited by glutathionylation. Mutant kinase containing an alanine to cysteine mutation at position 199 was resistant to inhibition by both diamide and glutathionylation, thus implicating this as the oxidation-sensitive site. Mouse fibroblast cells treated with diamide showed a reversible decrease in cAPK activity. Inhibition was dramatically enhanced when cells were first treated with cAPK activators. Using biotin-cysteine as means for detecting and purifying thiolated cAPK from cells, we were able to show that, under conditions in which cAPK is inactivated by diamide, it is also readily thiolated. 相似文献
999.
The IR (insulin receptor) and IGFR (type I insulin-like growth factor receptor) are found as homodimers, but the respective pro-receptors can also heterodimerize to form insulin-IGF hybrid receptors. There are conflicting data on the ligand affinity of hybrids, and especially on the influence of different IR isoforms. To investigate further the contribution of individual ligand binding epitopes to affinity and specificity in the IR/IGFR family, we generated hybrids incorporating both IR isoforms (A and B) and IR/IGFR domain-swap chimaeras, by ectopic co-expression of receptor constructs in Chinese hamster ovary cells, and studied ligand binding using both radioligand competition and bioluminescence resonance energy transfer assays. We found that IR-A-IGFR and IR-B-IGFR hybrids bound insulin with similar relatively low affinity, which was intermediate between that of homodimeric IR and homodimeric IGFR. However, both IR-A-IGFR and IR-B-IGFR hybrids bound IGF-I and IGF-II with high affinity, at a level comparable with homodimeric IGFR. Incorporation of a significant fraction of either IR-A or IR-B into hybrids resulted in abrogation of insulin- but not IGF-I-stimulated autophosphorylation. We conclude that the sequence of 12 amino acids encoded by exon 11 of the IR gene has little or no effect on ligand binding and activation of IR-IGFR hybrids, and that hybrid receptors bind IGFs but not insulin at physiological concentrations regardless of the IR isoform they contained. To reconstitute high affinity insulin binding within a hybrid receptor, chimaeras in which the IGFR L1 or L2 domains had been replaced by equivalent IR domains were co-expressed with full-length IR-A or IR-B. In the context of an IR-A-IGFR hybrid, replacement of IR residues 325-524 (containing the L2 domain and part of the first fibronectin domain) with the corresponding IGFR sequence increased the affinity for insulin by 20-fold. We conclude that the L2 and/or first fibronectin domains of IR contribute in trans with the L1 domain to create a high affinity insulin-binding site within a dimeric receptor. 相似文献
1000.
Kenneth M. D. Rutherford Sheena K. Robson Ramona D. Donald Susan Jarvis Dale A. Sandercock E. Marian Scott Andrea M. Nolan Alistair B. Lawrence 《Biology letters》2009,5(4):452-454
Pre-natal stress (PNS) or undernutrition can have numerous effects on an individual''s biology throughout their lifetime. Some of these effects may be adaptive by allowing individuals to tailor their phenotype to environmental conditions. Here we investigated, in the domestic pig Sus scrofa, whether one possible consequence of a predicted adverse environment could be altered pain perception. The behavioural response of piglets to the surgical amputation (‘docking’) of their tail or a sham procedure was measured for 1 min in piglets born to mothers who either experienced mid-gestation social stress or were left undisturbed throughout pregnancy. A behavioural pain score was found to predict the docked status of piglets with high discriminant accuracy. Piglets exposed to PNS had a significantly higher pain score than controls, and for each litter of tail-docked piglets, the average pain score was correlated with mid-gestation maternal cortisol levels. The data presented here provide evidence that the experience of stress in utero can result in a heightened acute response to injury in early life. Speculatively, this may represent an adaptive alteration occurring as a consequence of a pre-natal ‘early warning’ of environmental adversity. 相似文献