深圳双向转诊的利益相关者分析

利用利益相关者理论分析我国深圳社区健康中心与医院双向转诊中的各方利益者,包括主要利益相关者、次要利益相关者和外部利益相关者。社区居民、社区健康服务中心能获得预期利益,但是由于这些利益集团动用资源能力较弱,所以双向转诊仍然需要发挥政府的主导作用。     

Intermediate-consumer identity and resources alter a food web with omnivory

1. Omnivory is an important interaction that has been the centre of numerous theoretical and empirical studies in recent years. Most of these studies examine the conditions necessary for coexistence between an omnivore and an intermediate consumer. Trait variation in ecological interactions (competition and predator tolerance) among intermediate consumers has not been considered in previous empirical studies despite the evidence that variation in species-specific traits can have important community-level effects. 2. I conducted a multifactorial microcosm experiment using species from the Sarracenia purpurea phytotelmata community, organisms that inhabit the water collected within its modified leaves. The basal trophic level consisted of bacterial decomposers, the second trophic level (intermediate consumers) consisted of protozoa and rotifers, and the third trophic level (omnivore) were larvae of the pitcher plant mosquito Wyeomyia smithii. Trophic level number (1, 2 and 3), resources (low and high), omnivore density (low and high) and intermediate consumer (monoculture of five protozoa and rotifers) identity were manipulated. Abundance of the basal trophic level, intermediate consumers, and growth of the omnivore were measured, as well as time to extinction (intermediate consumers) and time to pupation (mosquito larvae). 3. The presence of different intermediate consumers affected both bacteria abundance and omnivore growth. At high resource levels, Poteriochromonas, Colpidium and Habrotrocha rosa reduced bacteria densities greater than omnivore reduction of bacteria. Mosquito larvae did not pupate at low resource levels except when Poteriochromonas and Colopoda were present as intermediate consumers. Communities with H. rosa were the only ones consistent with the prediction that omnivores should exclude intermediate consumers at high resources. 4. These results had mixed support for predictions from omnivory food web theory. Intermediate consumers responded and affected this community differently under different community structures and resource levels. Consequently, variation in species-specific traits can have important population- and community-level effects and needs to be considered in food webs with omnivory.     

Endostatin inhibits endochondral ossification

BACKGROUND: Angiogenesis is essential for the replacement of cartilage by bone during skeletal growth and regeneration. Vascular endothelial growth factor-A (VEGF-A) is a key regulator of angiogenesis whereas endostatin, a potent inhibitor of endothelial cell proliferation and migration, is a natural antagonist of VEGF-A. The regulatory role of these peptides in angiogenesis and bone formation was investigated using adenoviral gene delivery of VEGF-A and endostatin in a mouse ectopic ossification model. METHODS: Bone formation was induced in the hamstring muscles of adult mice with native bone morphogenetic protein (BMP) extract implemented in gelatine gel together with VEGF-A and endostatin recombinant adenoviral vectors. The mice were sacrificed 1, 2, and 3 weeks after the operation and ectopic bone formation was followed radiographically and histologically. RESULTS: Significant bone formation was induced by BMP extract in all treatment groups. VEGF-A stimulated and endostatin prevented the formation of FVIII-related antigen-positive vessels as well as the number of cartilage-resorbing chondroclasts/osteoclasts. Endostatin alone or in conjugation with VEGF-A reduced bone formation. Excess of VEGF-A stimulated and endostatin reduced bone formation, respectively, at the 3-week time point. CONCLUSIONS: Our findings indicate that endostatin retards the cartilage phase in endochondral ossification which subsequently reduces bone formation in our experimental model. We conclude that bone growth and healing, which share features with ectopic bone formation, may be regulated by endostatin.     

Social setting,intuition and experience in laboratory experiments interact to shape cooperative decision-making

Recent studies suggest that cooperative decision-making in one-shot interactions is a history-dependent dynamic process: promoting intuition versus deliberation typically has a positive effect on cooperation (dynamism) among people living in a cooperative setting and with no previous experience in economic games on cooperation (history dependence). Here, we report on a laboratory experiment exploring how these findings transfer to a non-cooperative setting. We find two major results: (i) promoting intuition versus deliberation has no effect on cooperative behaviour among inexperienced subjects living in a non-cooperative setting; (ii) experienced subjects cooperate more than inexperienced subjects, but only under time pressure. These results suggest that cooperation is a learning process, rather than an instinctive impulse or a self-controlled choice, and that experience operates primarily via the channel of intuition. Our findings shed further light on the cognitive basis of human cooperative decision-making and provide further support for the recently proposed social heuristics hypothesis.     

The macroevolutionary relationship between diet and body mass across mammals

Body mass and diet are two fundamental ecological parameters that influence many other aspects of an animal's biology. Thus, the potential physiological and ecological processes linking size and diet have been the subject of extensive research, although the broad macroevolutionary relationship between the two traits remains largely unexplored phylogenetically. Using generalized Ornstein–Uhlenbeck models and data on over 1350 species of mammal, we reveal that evolutionary changes in body mass are consistently associated with dietary changes across mammals. Best‐fitting models find that herbivores are substantially heavier than other dietary groups and that omnivores are frequently intermediate in mass between herbivores and carnivores. Interestingly, although flying and swimming both place very different physical constraints on mass, bats still follow the general mammalian pattern but marine mammals do not. Such differences may be explained by reduced gravitational constraints on size in water along with ecological differences in food availability between aquatic and terrestrial realms, allowing marine carnivores to become the largest mammals on earth. © 2015 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 115 , 173–184.     

Nox2 B-loop peptide, Nox2ds, specifically inhibits the NADPH oxidase Nox2

In recent years, reactive oxygen species (ROS) derived from the vascular isoforms of NADPH oxidase, Nox1, Nox2, and Nox4, have been implicated in many cardiovascular pathologies. As a result, the selective inhibition of these isoforms is an area of intense current investigation. In this study, we postulated that Nox2ds, a peptidic inhibitor that mimics a sequence in the cytosolic B-loop of Nox2, would inhibit ROS production by the Nox2-, but not the Nox1- and Nox4-oxidase systems. To test our hypothesis, the inhibitory activity of Nox2ds was assessed in cell-free assays using reconstituted systems expressing the Nox2-, canonical or hybrid Nox1-, or Nox4-oxidase. Our findings demonstrate that Nox2ds, but not its scrambled control, potently inhibited superoxide (O₂^•−) production in the Nox2 cell-free system, as assessed by the cytochrome c assay. Electron paramagnetic resonance confirmed that Nox2ds inhibits O₂^•− production by Nox2 oxidase. In contrast, Nox2ds did not inhibit ROS production by either Nox1- or Nox4-oxidase. These findings demonstrate that Nox2ds is a selective inhibitor of Nox2-oxidase and support its utility to elucidate the role of Nox2 in organ pathophysiology and its potential as a therapeutic agent.     

Engineering of 2-Cys peroxiredoxin for enhanced stress-tolerance

A typical 2-cysteine peroxiredoxin (2-Cys Prx)-like protein (PpPrx) that alternatively acts as a peroxidase or a molecular chaperone in Pseudomonas putida KT2440 was previously characterized. The dual functions of PpPrx are regulated by the existence of an additional Cys(112) between the active Cys(51) and Cys(171) residues. In the present study, additional Cys residues (Cys(31), Cys(112), and Cys(192)) were added to PpPrx variants to improve their enzymatic function. The optimal position of the additional Cys residues for the dual functionality was assessed. The peroxidase activities of the S31C and Y192C mutants were increased 3- to 4-fold compared to the wild-type, while the chaperone activity was maintained at > 66% of PpPrx. To investigate whether optimization of the dual functions could enhance stress-tolerance in vivo, a complementation study was performed. The S31C and Y192C mutants showed a much greater tolerance than other variants under a complex condition of heat and oxidative stresses. The optimized dual functions of PpPrx could be adapted for use in bioengineering systems and industries, such as to develop organisms that are more resistant to extreme environments.     

双联抗血小板治疗急性冠脉综合征临床疗效观察

目的:探讨双联抗血小板治疗急性冠脉综合征(ACS)的临床疗效和安全性。方法:60例ACS患者随机分为治疗组和对照组。对照组给予阿司匹林单抗血小板治疗,治疗组采用阿司匹林+氯吡格雷双联抗血小板治疗,治疗3个月后评价临床疗效。结果:治疗组临床疗效总有效率为93.3%,显著高于对照组(76.7%),相比较有显著性差异(P<0.05);治疗后,两组LVEF、CO、E/A显著上升,与治疗前比较均有显著性差异(P<0.05);且治疗组与对照组比较有显著性差异(P<0.05)。结论:阿司匹林和氯吡格雷双联抗血小板药物治疗ACS,可以强化对血小板聚集的抑制,并增强抗栓效果,值得临床应用。     

Characterization of hydrogen peroxide production by Duox in bronchial epithelial cells exposed to Pseudomonas aeruginosa

Hydrogen peroxide production by the NADPH oxidase Duox1 occurs during activation of respiratory epithelial cells stimulated by purified bacterial ligands, such as lipopolysaccharide. Here, we characterize Duox activation using intact bacterial cells of several airway pathogens. We found that only Pseudomonas aeruginosa, not Burkholderia cepacia or Staphylococcus aureus, triggers H₂O₂ production in bronchial epithelial cells in a calcium-dependent but predominantly ATP-independent manner. Moreover, by comparing mutant Pseudomonas strains, we identify several virulence factors that participate in Duox activation, including the type-three secretion system. These data provide insight on Duox activation by mechanisms unique to P. aeruginosa.     

Translocation and conservation of organic nitrogen within the coral-zooxanthella symbiotic system of Acropora pulchra, as demonstrated by dual isotope-labeling techniques

Carbon (C) and nitrogen (N) metabolism of the hermatypic coral Acropora pulchra and its symbiotic algae (zooxanthellae) was investigated using ¹³C and ¹⁵N isotope tracers. A. pulchra was incubated in seawater containing ¹³C-labeled bicarbonate and ¹⁵N-labeled nitrate (NO₃⁻) for 24 h (pulse period), and subsequently ¹³C and ¹⁵N isotopic ratios of the host coral and the zooxanthellae were followed in ¹³C- and ¹⁵N-free seawater for 2 weeks (chase period). Under our experimental condition of NO₃⁻ (12 μM), C and N were absorbed by the coral-algal symbiotic system with the C:N ratio of 23 during the pulse period. Taking account of concentration dependence of NO₃⁻ uptake rates determined by a separate experiment, C:N uptake ratios under supposed in situ NO₃⁻ conditions (< 1.0 μM) would be > 3.0 times higher, if the photosynthetic rate did not change. During the pulse period, more than half of the absorbed ¹³C and ¹⁵N appeared in the host fraction in organic forms. ¹³C:¹⁵N ratio at the end of the pulse period was similar between the host and the algal fraction, suggesting that algal photosynthetic products were translocated to the host. It is also implied that C:N ratios of the translocated products change depending on N availability for the zooxanthellae. During the chase period, atom % excess (APE) ¹⁵N of the zooxanthellae constantly declined, while that of the host slightly increased. Consequently, APE ¹⁵N of the both fractions appeared to approach a common steady state value, suggesting that ¹⁵N was recycled within the coral-algal symbiotic system. As for C, > 86% of C photosynthetically fixed by the zooxanthellae accumulated in the host at the end of the pulse period, and had a turnover time of ca. 20 days for the host C pool during the following chase period. C:N ratios of organic matter newly synthesized with NO₃⁻ exponentially declined and converged into 5.7 and 4.5 for the host and the zooxanthellae, respectively. This suggests that organic compounds of high C:N ratios such as lipids and carbohydrates were selectively consumed more rapidly than those of low C:N ratios such as proteins and nucleic acids.