预见性压疮预防护理在ICU患者中应用效果

目的:探讨预见性压疮预防护理在ICU患者中应用的效果。方法:选取2011年4月至2012年12月入住ICU的危重症患者68例作为对照组,2013年1月至2014年8月ICU危重症患者68例为干预组。对照组采取常规护理方法,干预组采用预见性压疮预防护理措施。结果:干预组患者压疮发生率为19.12%,明显低于对照组的51.47%（P<0.01）;干预组患者压疮严重程度轻于对照组（P<0.05）。结论:预见性压疮预防护理的应用可有效降低ICU患者压疮的发生率和压疮严重程度。     

Circulating Micro RNA-21is Downregulatedin Patients with Metabolic Syndrome

正The microRNA-21(miR-21)is known to play a major role in cancer progression;however,its function in the cardiovascular system appears to be even more complex and conflicting.To characterize miR-21 expression in the plasma of individuals with     

疼痛、安慰剂的研究进展

疼痛与安慰剂是健康心理学中重要的内容。本文分别探讨了疼痛与安慰剂的定义、心理学影响因素、研究现状以及安慰剂镇痛作用的研究进展与面临的挑战。     

Linked selection and recombination rate variation drive the evolution of the genomic landscape of differentiation across the speciation continuum of Ficedula flycatchers

Speciation is a continuous process during which genetic changes gradually accumulate in the genomes of diverging species. Recent studies have documented highly heterogeneous differentiation landscapes, with distinct regions of elevated differentiation (“differentiation islands”) widespread across genomes. However, it remains unclear which processes drive the evolution of differentiation islands; how the differentiation landscape evolves as speciation advances; and ultimately, how differentiation islands are related to speciation. Here, we addressed these questions based on population genetic analyses of 200 resequenced genomes from 10 populations of four Ficedula flycatcher sister species. We show that a heterogeneous differentiation landscape starts emerging among populations within species, and differentiation islands evolve recurrently in the very same genomic regions among independent lineages. Contrary to expectations from models that interpret differentiation islands as genomic regions involved in reproductive isolation that are shielded from gene flow, patterns of sequence divergence (d_xy and relative node depth) do not support a major role of gene flow in the evolution of the differentiation landscape in these species. Instead, as predicted by models of linked selection, genome-wide variation in diversity and differentiation can be explained by variation in recombination rate and the density of targets for selection. We thus conclude that the heterogeneous landscape of differentiation in Ficedula flycatchers evolves mainly as the result of background selection and selective sweeps in genomic regions of low recombination. Our results emphasize the necessity of incorporating linked selection as a null model to identify genome regions involved in adaptation and speciation.Uncovering the genetic architecture of reproductive isolation and its evolutionary history are central tasks in evolutionary biology. The identification of genome regions that are highly differentiated between closely related species, and thereby constitute candidate regions involved in reproductive isolation, has recently been a major focus of speciation genetic research. Studies from a broad taxonomic range, involving organisms as diverse as plants (Renaut et al. 2013), insects (Turner et al. 2005; Lawniczak et al. 2010; Nadeau et al. 2012; Soria-Carrasco et al. 2014), fishes (Jones et al. 2012), mammals (Harr 2006), and birds (Ellegren et al. 2012) contribute to the emerging picture of a genomic landscape of differentiation that is usually highly heterogeneous, with regions of locally elevated differentiation (“differentiation islands”) widely spread over the genome. However, the evolutionary processes driving the evolution of the differentiation landscape and the role of differentiation islands in speciation are subject to controversy (Turner and Hahn 2010; Cruickshank and Hahn 2014; Pennisi 2014).Differentiation islands were originally interpreted as “speciation islands,” regions that harbor genetic variants involved in reproductive isolation and are shielded from gene flow by selection (Turner et al. 2005; Soria-Carrasco et al. 2014). During speciation-with-gene-flow, speciation islands were suggested to evolve through selective sweeps of locally adapted variants and by hitchhiking of physically linked neutral variation (“divergence hitchhiking”) (Via and West 2008); gene flow would keep differentiation in the remainder of the genome at bay (Nosil 2008; Nosil et al. 2008). In a similar way, speciation islands can arise by allopatric speciation followed by secondary contact. In this case, genome-wide differentiation increases during periods of geographic isolation, but upon secondary contact, it is reduced by gene flow in genome regions not involved in reproductive isolation. In the absence of gene flow in allopatry, speciation islands need not (but can) evolve by local adaptation, but may consist of intrinsic incompatibilities sensu Bateson-Dobzhansky-Muller (Bateson 1909; Dobzhansky 1937; Muller 1940) that accumulated in spatially isolated populations.However, whether differentiation islands represent speciation islands has been questioned. Rather than being a cause of speciation, differentiation islands might evolve only after the onset of reproductive isolation as a consequence of locally accelerated lineage sorting (Noor and Bennett 2009; Turner and Hahn 2010; White et al. 2010; Cruickshank and Hahn 2014; Renaut et al. 2014), such as in regions of low recombination (Nachman 2002; Sella et al. 2009; Cutter and Payseur 2013). In these regions, the diversity-reducing effects of both positive selection and purifying selection (background selection [BGS]) at linked sites (“linked selection”) impact physically larger regions due to the stronger linkage among sites. The thereby locally reduced effective population size (N_e) will enhance genetic drift and hence inevitably lead to increased differentiation among populations and species.These alternative models for the evolution of a heterogeneous genomic landscape of differentiation are not mutually exclusive, and their population genetic footprints can be difficult to discern. In the cases of (primary) speciation-with-gene-flow and gene flow at secondary contact, shared variation outside differentiation islands partly stems from gene flow. In contrast, under linked selection, ancestral variation is reduced and differentiation elevated in regions of low recombination, while the remainder of the genome may still share considerable amounts of ancestral genetic variation and show limited differentiation. Many commonly used population genetic statistics do not capture these different origins of shared genetic variation and have the same qualitative expectations under both models, such as reduced diversity (π) and skews toward an excess of rare variants (e.g., lower Tajima''s D) in differentiation islands relative to the remainder of the genome. However, since speciation islands should evolve by the prevention or breakdown of differentiation by gene flow in regions not involved in reproductive isolation, substantial gene flow should be detectable in these regions (Cruickshank and Hahn 2014) and manifested in the form of reduced sequence divergence (d_xy) or as an excess of shared derived alleles in cases of asymmetrical gene flow (Patterson et al. 2012). Under linked selection, predictions are opposite for d_xy (Cruickshank and Hahn 2014), owing to reduced ancestral diversity in low-recombination regions. Further predictions for linked selection include positive and negative relationships of recombination rate with genetic diversity (π) and differentiation (F_ST), respectively, and inverse correlations of the latter two with the density of targets for selection. Finally, important insights into the nature of differentiation islands may be gained by studying the evolution of differentiation landscapes across the speciation continuum. Theoretical models and simulations of speciation-with-gene-flow predict that after an initial phase during which differentiation establishes in regions involved in adaptation, differentiation should start spreading from these regions across the entire genome (Feder et al. 2012, 2014; Flaxman et al. 2013).Unravelling the processes driving the evolution of the genomic landscape of differentiation, and hence understanding how genome differentiation unfolds as speciation advances, requires genome-wide data at multiple stages of the speciation continuum and in a range of geographical settings from allopatry to sympatry (Seehausen et al. 2014). Although studies of the speciation continuum are emerging (Hendry et al. 2009; Kronforst et al. 2013; Shaw and Mullen 2014, and references therein), empirical examples of genome differentiation at multiple levels of species divergence remain scarce (Andrew and Rieseberg 2013; Kronforst et al. 2013; Martin et al. 2013), and to our knowledge, have so far not jointly addressed the predictions of alternative models for the evolution of the genomic landscape of differentiation. In the present study, we implemented such a study design encompassing multiple populations of four black-and-white flycatcher sister species of the genus Ficedula (Fig. 1A,B; Supplemental Fig. S1; for a comprehensive reconstruction of the species tree, see Nater et al. 2015). Previous analyses in collared flycatcher (F. albicollis) and pied flycatcher (F. hypoleuca) revealed a highly heterogeneous differentiation landscape across the genome (Ellegren et al. 2012). An involvement of gene flow in its evolution would be plausible, as hybrids between these species occur at low frequencies in sympatric populations in eastern Central Europe and on the Baltic Islands of Gotland and Öland (Alatalo et al. 1990; Sætre et al. 1999), although a recent study based on genome-wide markers identified no hybrids beyond the F₁ generation (Kawakami et al. 2014a). Still, gene flow from pied into collared flycatcher appears to have occurred (Borge et al. 2005; Backström et al. 2013; Nadachowska-Brzyska et al. 2013) despite premating isolation (for review, see Sætre and Sæther 2010), hybrid female sterility (Alatalo et al. 1990; Tegelström and Gelter 1990), and strongly reduced long-term fitness of hybrid males (Wiley et al. 2009). Atlas flycatcher (F. speculigera) and semicollared flycatcher (F. semitorquata) are two closely related species, which have been less studied, but may provide interesting insights into how genome differentiation evolves over time. Here, we take advantage of this system to identify the processes underlying the evolution of differentiation islands based on the population genetic analysis of whole-genome resequencing data of 200 flycatchers.Open in a separate windowFigure 1.A recurrently evolving genomic landscape of differentiation across the speciation continuum in Ficedula flycatchers. (A) Species’ neighbor-joining tree based on mean genome-wide net sequence divergence (d_A). The same species tree topology was inferred with 100% bootstrap support from the distribution of gene trees under the multispecies coalescent (Supplemental Fig. S1). (B) Map showing the locations of population sampling and approximate species ranges. (C) Population genomic parameters along an example chromosome (Chromosome 4A) (see Supplemental Figs. S2, S4 for all chromosomes). Color codes for specific–specific parameters: (blue) collared; (green) pied; (orange) Atlas; (red) semicollared. Color codes for d_xy: (green) collared-pied; (light blue) collared-Atlas; (blue) collared-semicollared; (orange) pied-Atlas; (red) pied-semicollared; (black) Atlas-semicollared. For differentiation within species, comparisons with the Italian (collared) and Spanish (pied) populations are shown. Color codes for F_ST within collared flycatchers: (cyan) Italy–Hungary; (light blue) Italy–Czech Republic; (dark blue) Italy–Baltic. Color codes for F_ST within pied flycatchers: (light green) Spain–Sweden; (green) Spain–Czech Republic; (dark green) Spain–Baltic. (D) Distributions of differentiation (F_ST) from collared flycatcher along the speciation continuum. Distributions are given separately for three autosomal recombination percentiles (33%; 33%–66%; 66%–100%) corresponding to high (>3.4 cM/Mb, blue), intermediate (1.3–3.4 cM/Mb, orange), and low recombination rate (0–1.3 cM/Mb, red), and the Z Chromosome (green). Geographically close within-species comparison: Italy–Hungary. Comparisons within species include the geographically close Italian and Hungarian populations (within [close]), and the geographically distant Italian and Baltic populations (within [far]). Geographically far within-species comparison: Italy–Baltic. (E) Differentiation from collared flycatcher along an example chromosome (Chromosome 11) (see Supplemental Fig. S3 for all chromosomes). Color codes for between-species comparisons: (green) pied; (orange) Atlas; (red) semicollared; (dark red) red-breasted; (black) snowy-browed flycatcher. Color codes for within-species comparisons: (cyan) Italy–Hungary; (blue) Italy–Baltic. Flycatcher artwork in panel A courtesy of Dan Zetterström.     

Detection of skin temperature differences using palpation by manual physical therapists and lay individuals

Objectives—To evaluate the accuracy of detection of temperature differences among skin sites of lay individuals and manual physical therapists.Methods— Forty-four manual physical therapists and 44 lay individuals were recruited. Subjects palpated two temperature-controlled surfaces that ranged in temperature between 30 and 35 °C and varied randomly by 1, 2, 3, 4, or 5 °C for 10 s. The subjects were then asked to identify the warmer pad.Results— Accuracy increased with larger temperature differences. Accuracy of detection of 1 and 3 °C temperature differences was higher in manual physical therapists than lay individuals.Discussion— Palpation can be used to accurately detecting temperature differences between sites and is more accurately performed by an experienced practitioner.

Level of Evidence: 3b     

A systematic review and meta‐analysis of randomized controlled trials: Skin‐patch of Chinese herbal medicine for patients with acute gouty arthritis

Aims

To evaluate the evidence of the effectiveness and safety of Chinese herbal medicine skin‐patches for patients with acute gouty arthritis.

Background

Acute gouty arthritis is a problem that can limit the level of activity and impair the quality of life. In China, many clinical studies have demonstrated that skin‐patches of Chinese herbal medicines benefit patients with acute gouty arthritis. However, the reported clinical effects vary.

Design

A systematic review and meta‐analysis of randomized controlled trials.

Data sources

Three English databases including CENTRAL (1993 to February 2017), PubMed (1966 to February 2017) and EMBASE (1974 to February 2017) and four Chinese databases including Chinese National Knowledge Infrastructure, Chinese VIP Information, SinoMed and Wanfang (all, 1949 ‐ February 2017) were searched. Randomized controlled trials that compared skin‐patches of Chinese herbal medicine with or without conventional treatments to conventional treatments, no treatment or a placebo treatment for patients with acute gouty arthritis were included.

Review methods

We conducted a systematic review and meta‐analysis following the Cochrane process. Two authors selected the studies, extracted the data and evaluated the risk of bias of the included trials.

Results

Nineteen studies met our inclusion criteria. After synthesizing the data, the results showed that skin‐patches of CHM combined with Western medicine seemed to be more effective than Western medicine alone for pain relief in patients with acute gouty arthritis and had fewer adverse events.

Conclusion

Due to the quality of the data, larger and more rigorously designed clinical trials with proper outcome measures are necessary.     

Dietary nucleotides supplementation during the suckling period improves the antioxidative ability of neonates with intrauterine growth retardation when using a pig model

The aim of the present study was to investigate the effect of dietary nucleotides supplementation on the antioxidant status of piglets affected by intrauterine growth retardation (IUGR). Fourteen pairs of normal birth weight (NBW) and IUGR piglets were fed either a control diet (CON) or a nucleotides supplementation diet (NT) from 7 d of age to 28 d postnatal. Blood, liver and jejunum samples were collected at the end of the study. The results showed that IUGR piglets had decreased (P < 0.05) concentrations of plasma total antioxidant capability (T-AOC) and total superoxide dismutase (T-SOD), gene expressions of hepatic cytoplasmic copper/zinc SOD (CuZnSOD) and PPARγ coactivator-1α (PGC-1α) and jejunal glutathione peroxidase (GP_X) and extracellular superoxide dismutase (ESOD), accordingly, there was markedly higher (P < 0.05) plasma malondialdehyde (MDA) and hepatic and jejunal mitochondria DNA content in the IUGR piglets relative to NBW piglets. Regardless of body weight, dietary NT supplementation significantly increased (P < 0.05) plasma concentrations of T-AOC, T-SOD, CuZnSOD, GP_X and the ratio of reduced glutathione to oxidized glutathione, hepatic T-SOD, GP_X and mitochondria DNA content, while hepatic MDA concentration was markedly decreased (P < 0.05) 19.1% by NT diet. Furthermore, the gene expressions of hepatic glutathione reductase, CuZnSOD, nuclear erythroid 2-related factor 2, PGC-1α and nuclear respiratory factor-1 (NRF-1) and jejunal GP_X, CuZnSOD, ESOD and NRF-1 were significantly increased (P < 0.05) by NT diet, whereas the gene expression of Kelch-like ECH-associated protein 1 were markedly decreased (P < 0.05) compared with that of piglets fed with CON diet. These results indicate that dietary NT supplementation prevents the effect of IUGR on oxidative status and mitochondria DNA damage through improving the non-enzymatic and enzymatic antioxidant capacities as well as mitochondria biogenesis of piglets.

The aim of the present study was to investigate the effect of dietary nucleotides supplementation on the antioxidant status of piglets affected by intrauterine growth retardation (IUGR).     

Zein regulating apatite mineralization,degradability, in vitro cells responses and in vivo osteogenesis of 3D-printed scaffold of n-MS/ZN/PCL ternary composite

Bioactive and degradable scaffolds of nano magnesium silicate (n-MS)/zein (ZN)/poly(caprolactone) (PCL) ternary composites were prepared by 3D-printing method. The results showed that the 3D-printed scaffolds possessed controllable pore structure, and pore morphology, pore size, porosity and pore interconnectivity of the scaffolds can be efficiently adjusted. In addition, the apatite-mineralization ability of the scaffolds in simulated body fluids was obviously improved with the increase of ZN content, in which the scaffold with 20 w% ZN (C20) possessed excellent apatite-mineralization ability. Moreover, the degradability of the scaffolds was significantly enhanced with the increase of ZN content in the scaffolds. The degradation of ZN produced acidic products that could neutralize the alkaline products from the degradation of n-MS, which avoid the increase of pH value in degradable solution. Furthermore, the MC3T3-E1 cells responses (e.g. proliferation and differentiation, etc.) to the scaffolds were significantly promoted with the increase of ZN content. The in vivo osteogenesis of the scaffolds implanted the femur defects of rabbits was investigated by micro-CT and histological analysis. The results demonstrated that the new bone formation was significantly enhanced with the increase of ZN content, in which the C20 scaffold induced the highest new bone tissues, indicating excellent osteogenesis. The results suggested that the ZN in the ternary composite scaffolds played key roles in assisting bone regeneration in vivo.

Zein regulating apatite mineralization, degradability, cells responses and osteogenesis of 3D-printed scaffold of n-MS/ZN/PCL ternary composite.     

Folate Deficiency Decreases Apoptosis of Endometrium Decidual Cells in Pregnant Mice via the Mitochondrial Pathway

It is well known that maternal folate deficiency results in adverse pregnancy outcomes. In addition to aspects in embryonic development, maternal uterine receptivity and the decidualization of stromal cells is also very important for a successful pregnancy. In this study, we focused on endometrium decidualization and investigated whether apoptosis, which is essential for decidualization, was impaired. Flow cytometry and TUNEL detection revealed that apoptosis of mouse endometrium decidual cells was suppressed in the dietary folate-deficient group on Days 7 and 8 of pregnancy (Day 1 = vaginal plug) when decidua regression is initiated. The endometrium decidual tissue of the folate deficiency group expressed less Bax compared to the normal diet group while they had nearly equal expression of Bcl2 protein. Further examination revealed that the mitochondrial transmembrane potential (ΔΨm) decreased, and the fluorescence of diffuse cytoplasmic cytochrome c protein was detected using laser confocal microscopy in normal decidual cells. However, no corresponding changes were observed in the folate-deficient group. Western blotting analyses confirmed that more cytochrome c was released from mitochondria in normal decidual cells. Taken together, these results demonstrated that folate deficiency could inhibit apoptosis of decidual cells via the mitochondrial apoptosis pathway, thereby restraining decidualization of the endometrium and further impairing pregnancy.