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Background

There is increasing recognition of sex/gender differences in health and the importance of identifying differential effects of interventions for men and women. Yet, to whom the research evidence does or does not apply, with regard to sex/gender, is often insufficiently answered. This is also true for systematic reviews which synthesize results of primary studies. A lack of analysis and reporting of evidence on sex/gender raises concerns about the applicability of systematic reviews. To bridge this gap, this pilot study aimed to translate knowledge about sex/gender analysis (SGA) into a user-friendly ‘briefing note’ format and evaluate its potential in aiding the implementation of SGA in systematic reviews.

Methods

Our Sex/Gender Methods Group used an interactive process to translate knowledge about sex/gender into briefing notes, a concise communication tool used by policy and decision makers. The briefing notes were developed in collaboration with three Cochrane Collaboration review groups (HIV/AIDS, Hypertension, and Musculoskeletal) who were also the target knowledge users of the briefing notes. Briefing note development was informed by existing systematic review checklists, literature on sex/gender, in-person and virtual meetings, and consultation with topic experts. Finally, we held a workshop for potential users to evaluate the notes.

Results

Each briefing note provides tailored guidance on considering sex/gender to reviewers who are planning or conducting systematic reviews and includes the rationale for considering sex/gender, with examples specific to each review group’s focus. Review authors found that the briefing notes provided welcome guidance on implementing SGA that was clear and concise, but also identified conceptual and implementation challenges.

Conclusions

Sex/gender briefing notes are a promising knowledge translation tool. By encouraging sex/gender analysis and equity considerations in systematic reviews, the briefing notes can assist systematic reviewers in ensuring the applicability of research evidence, with the goal of improved health outcomes for diverse populations.  相似文献   

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Toxoplasmosis is a health concern for wildlife and humans, particularly in island ecosystems. In the Galápagos Islands, exposure to Toxoplasma gondii has been found in marine avifauna on islands with and without domestic cats. To evaluate potential waterborne transmission of T. gondii, we attempted to use filtration and epifluorescent microscopy to detect autofluorescent T. gondii oocysts in fresh and estuarine surface water samples. T. gondii oocyst-like structures were microscopically visualized but were not confirmed by polymerase chain reaction and sequence analyses. Further research is needed to refine environmental pathogen screening techniques and to evaluate disease risk of waterborne zoonoses such as T. gondii for wildlife and humans, particularly in the Galápagos and other naive island ecosystems.  相似文献   

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Predicting the biological function potential of post-translational modifications (PTMs) is becoming increasingly important in light of the exponential increase in available PTM data from high-throughput proteomics. We developed structural analysis of PTM hotspots (SAPH-ire)—a quantitative PTM ranking method that integrates experimental PTM observations, sequence conservation, protein structure, and interaction data to allow rank order comparisons within or between protein families. Here, we applied SAPH-ire to the study of PTMs in diverse G protein families, a conserved and ubiquitous class of proteins essential for maintenance of intracellular structure (tubulins) and signal transduction (large and small Ras-like G proteins). A total of 1728 experimentally verified PTMs from eight unique G protein families were clustered into 451 unique hotspots, 51 of which have a known and cited biological function or response. Using customized software, the hotspots were analyzed in the context of 598 unique protein structures. By comparing distributions of hotspots with known versus unknown function, we show that SAPH-ire analysis is predictive for PTM biological function. Notably, SAPH-ire revealed high-ranking hotspots for which a functional impact has not yet been determined, including phosphorylation hotspots in the N-terminal tails of G protein gamma subunits—conserved protein structures never before reported as regulators of G protein coupled receptor signaling. To validate this prediction we used the yeast model system for G protein coupled receptor signaling, revealing that gamma subunit–N-terminal tail phosphorylation is activated in response to G protein coupled receptor stimulation and regulates protein stability in vivo. These results demonstrate the utility of integrating protein structural and sequence features into PTM prioritization schemes that can improve the analysis and functional power of modification-specific proteomics data.Post-translational modifications (PTMs)1 are a rapidly expanding and important class of protein feature that broaden the functional diversity of proteins in a proteome. By definition, PTMs change protein structure and therefore have the potential to affect protein function by altering protein interactions, protein stability or catalytic activity (1, 2). As they have been found to occur on nearly every protein in the eukaryotic proteome, PTMs broadly impact nearly all known cellular processes. Over 300 different types of PTM are known, ranging from single atom modifications (e.g. oxide) to small protein modifiers (e.g. ubiquitin), which can occur on all but five amino acid residues resulting from enzymatic or nonenzymatic processes (3). Over 220,000 distinct PTM sites have been experimentally identified across ∼77,000 different proteins to date (dbPTM; http://dbptm.mbc.nctu.edu.tw/statistics.php) – numbers that continue to grow exponentially because of improved methods for high throughput detection by mass spectrometry (MS). By virtue of how they are detected, most PTM data are sequence-linked and lack structural context.The function of most PTMs is unknown because the rate of PTM detection far surpasses the rate at which any one modification can be studied empirically. Moreover, the functional impact of every PTM is likely not equivalent (4). For example, computational analysis of phosphorylation sites in yeast and human proteomes indicate that well-conserved phosphosites are more likely to have a functional consequence compared with poorly conserved sites, yet only a fraction of phosphosites are well conserved (5, 6). Consequently, the development of tools that provide functional prioritization of PTMs could have a broad impact on our understanding of protein regulation, biological mechanism, and molecular evolution.The emerging need for methods that predict the functional impact of a PTM has not yet been met. Longstanding methods capitalize predominantly on the sequence context of PTMs and have been used to predict sites of modification (expasy.org/proteomics/post-translational_modification) and to compare enzyme/substrate interactions (79). More recently, studies aimed at expanding the parameters associated with functional PTMs have emerged. In these cases, a set of common features correlated with functional importance are derived from the analysis of PTMs within and between organisms including: number of PTM observations at a multiple sequence alignment position (i.e. hotspots), measures of co-occurrence between different PTMs (e.g. distance between phosphorylation and ubiquitination sites), biological dynamics (up or down-regulation), and protein–protein interaction influence (7, 1012). Recent efforts to provide structural context by linking individual PTMs to three-dimensional structures in the protein data bank (PDB) have also been described (13, 14). However, these resources are extensions of existing PTM databases that allow visualization of single instances of modification onto individual proteins, but do not provide quantitative or analytical value.In principle, combining PTM hotspot and structural analysis would offer multiple advantages over any one approach used in isolation. Sequence homology provides protein family membership—thereby clustering PTMs into hotspots for groups of proteins to provide information about: (1) the evolutionary conservation and (2) observation frequencies of PTMs within the family. A primary consequence of their sequence homology is that members of a protein family will exhibit similar structures and protein interactions—features that dictate the function of protein systems. A secondary consequence is that PTM hotspots generated by alignment can be projected onto family-representative protein structures, which places each PTM hotspot into a three-dimensional context that can be visualized for each family. The structural context enabled by this projection can also provide spatial information about the PTM site that can supplement the sequence characteristics of the hotspot, namely: (3) solvent accessibility, which provides an estimate of whether a modification could occur on the folded protein; and (4) protein interface residence, which indicates the potential of the PTM to disrupt protein–protein interactions. Despite the theoretical advantages, no single tool has been developed that exploits the quantitative output from both sequence and structural data to evaluate the function potential of PTMs.Here we describe a new analytical method – Structural Analysis of PTM Hotspots (SAPH-ire), which ranks PTM hotspots by their potential to impact biological function for distinct protein families (Fig. 1). We demonstrate the application of SAPH-ire to the complete set of PTMs for eight distinct protein families including large heterotrimeric G proteins—revealing high-ranking hotspots for which a biological function has not yet been determined. In particular, SAPH-ire revealed the N-terminal tail (Nt) of G protein gamma (Gγ) subunits as one of the highest ranking PTM hotspots for heterotrimeric G proteins (Gα, Gβ, and Gγ). We tested this prediction by monitoring the phosphorylation state and mutation effects of phosphorylation sites in the N terminus of the yeast Gγ subunit (Ste18). Consistent with SAPH-ire predictions, we found that phosphorylation of Ste18-Nt is biologically responsive to a GPCR stimulus and that phospho-null or phospho-mimic mutation of these sites controls protein abundance in an opposite manner in vivo. Thus, SAPH-ire is a powerful new method for predicting the function potential of PTM hotspots, which can guide empirical research toward the discovery of new protein regulatory elements based on high-throughput proteomics.Open in a separate windowFig. 1.Schematic diagram of the SAPH-ire method. A, SAPH-ire integrates InterPro, the Protein Data bank (PDB) and a customized database of experimentally validated PTMs. Uniprot entries with PTMs that belong to specific InterPro-classified protein families undergo multiple-sequence alignment (MSA) and PTM hotspot analysis (HSA), which layers all PTMs for a given alignment position in the MSA. The total PTMs observed in each hotspot and the conservation of a modifiable residue (e.g. conservation lysine at a ubiquitination hotspot) at the hotspot are quantified. B, PTM hotspots within the protein family are then projected onto all known crystal structures for the family using the Structural Projection of PTMs (SPoP) tool. From the structural topology of PTM hotspots generated by SPoP, the solvent accessible surface area (SASA) and protein interface residence is quantified for each hotspot. C, PTM Function Potential Calculator (FPC) integrates the output from HSA and SPoP, resulting in PTM function potential scores for each hotspot. The function potential score can be used to rank PTM hotspots within or between protein families – prioritizing hotspots with the greatest potential to be biologically regulated and/or effect a biological function for the protein family of interest.  相似文献   

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The morphological features of the third instar larva of the most important insect model, Drosophila melanogaster, are documented for the first time using a broad spectrum of modern morphological techniques. External structures of the body wall, the cephaloskeleton, and the musculature are described and illustrated. Additional information about other internal organs is provided. The systematic implications of the findings are discussed briefly. Internal apomorphic features of Brachycera and Cyclorrhapha are confirmed for Drosophila. Despite the intensive investigations of the phylogeny of the megadiverse Diptera, evolutionary reconstructions are still impeded by the scarcity of anatomical data for brachyceran larvae. The available morphological information for the life stages of three insect model organisms – D. melanogaster (Diptera, Drosophilidae), Manduca sexta (Lepidoptera, Sphingidae) and Tribolium castaneum (Coleoptera, Tenebrionidae) - is addressed briefly. The usefulness of a combination of traditional and innovative techniques for an optimized acquisition of anatomical data for different life stages is highlighted.  相似文献   

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The impoundment of reservoirs temporarily increases the methylation of mercury bound to flooded soils and vegetation and the transfer of methylmercury (MeHg) to fish. MeHg levels in various fish species of hydroelectric reservoirs located in the James Bay territory increased by factors of 3 to 7, then gradually declined toward initial concentrations 10 to 20 years after flooding, depending on reservoir characteristics. The potential risk of increased MeHg exposure for recreational anglers who consume fish from these reservoirs had not been assessed previously. A less invasive method than systematic measurement of Hg levels in hair was developed to determine MeHg exposure of recreational anglers. A fish consumption questionnaire-based approach was combined with a toxicokinetic model to estimate the corresponding hair MeHg concentrations. The results were compared with actual analytical determinations of hair Hg levels for the 94 recreational anglers recruited for the study. The values predicted by the model based on self-reporting consumption overestimated actual hair Hg levels by an average factor greater than 6. The mean hair level predicted for the most recent period (September-October) was 23.3?µg.g?1 compared to 3.6 µg.g?1 for the measured value. Although the questionnaire protocol may certainly be improved to increase the precision of estimations, direct hair Hg measurement remains the more effective means to assess Hg exposure.  相似文献   

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The past decade has seen considerable developments in the integrated study of ecosystem sustainability and health. Important developments in theory, methods, and application of this area have emerged from the work of key individuals and informal, multidisciplinary networks of peers working across continents and countries and based in governments, universities, and private organizations. This profile focuses in particular on the critical influence of James Kay as a key advocate and intellectual champion for incorporating complexity and uncertainty into the Ecosystem approach. The intent is to provide an overview of an important era in the application of this approach to address health and sustainability concerns and to highlight the frameworks, methods, and networks that have emerged as collective acknowledgments to the life and work of James Kay (1954–2004).  相似文献   

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We edited, redrew, and evaluated four unpublished historical vegetation maps of the Western Pamirs (Tajikistan) by the Soviet geobotanist Okmir E. Agakhanjanz. These maps cover an area of 5,188 km2 and date from 1958 to 1960. The purpose of this article is to make the historic vegetation data available to the scientific community and thus preserve a hitherto non available and up to now neglected or forgotten data source with great potential for studies on vegetation and ecosystem response to global change. The original hand-drawn maps were scanned, georeferenced, and digitized and the corresponding land cover class was assigned to each polygon. The partly differing legends were harmonized and plant names updated. Furthermore, a digital elevation model and generalized additive models were used to calculate response curves of the land cover classes and to explore vegetation-topography relationships quantitatively. In total, 2,216 polygons belonging to 13 major land cover classes were included that are characterized by 252 different plant species. As such, the presented maps provide excellent comparison data for studies on vegetation and ecosystem change in an area that is deemed to be an important water tower in Central Asia.  相似文献   

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Coal is one of the most abundant nonrenewable fossil fuels, in Pakistan. However, in general, the quality of coal is too low to offset the practical, economic, and regulatory barriers to its utilization. High sulfur content comes up as one of the bottlenecks in productive usage of indigenous coal. Biotechnology can emerge as a panacea for upgrading the huge reserves of high sulfur coal. In current study, the sulfur removal potential of Rhodococcus spp. (Eu-32) was investigated using coal from Dukki, Baluchistan, Pakistan. Biodesulfurization process was optimized for various parameters and maximum decrease of 40% and 60% in total and organic sulfur contents, respectively were achieved in 15 days. The Langmuir and Brunauer–Emmett–Teller (BET) surface areas of the biotreated coal were increased by 20 and 16 times, respectively. Scanning electron microscope showed higher tendency of attachment of bacterial cells to the coal particles. Our results revealed that Eu-32 could remove significant amounts of organic sulfur from coal and could be used in the pre-combustion operations with appropriate arrangements.  相似文献   

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An efficient overall two-step strategy for the synthesis of (E)-5-aminoallyl-pyrimidine-5′-triphoshate, starting from commercially available pyrimidine-5′-triphosphate is described. The method involves regioselective iodination of pyrimidine-5′-triphosphate, followed by the palladium-catalyzed Heck coupling with allylamine. The catalytic reaction is highly stereoselective and compatible with many functional groups present in the reactants.  相似文献   

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We present novel microsatellite markers of the Japanese abalone (Haliotis discus hannai) for general mapping studies in this species. A total of 75 microsatellite markers were developed, and the allele-transmission patterns of these markers were studied in three families generated by pair crosses. For allele scoring, we employed the 5′-tailed primer polymerase chain reaction (PCR) technique, which substantially reduces the cost for fluorescent labeling of primers. Of the 225 possible marker-family combinations (75 markers × 3 families), 18 cases of informative null-allele segregation were inferred. When such null-allele segregations were allowed, more than 70% of the 75 markers in the families turned out to be markers with an expected segregation ratio of 1:1:1:1, allowing maximal exploitation of the codominant nature of microsatellite markers. There were 16 instances of segregation distortion at the 5% significance level. The test for independence of segregation assigned the 75 markers into 17 linkage groups, which is in close agreement with the haploid chromosome number of H. discus hannai (n = 18). Six markers could not be placed into any linkage group. We suggest that these markers could help construct a H. discus hannai linkage map.  相似文献   

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Abstract

The cytotoxicity of Gemcitabine (dFdC) was 10 (ovarian cancer) to > 10,000 (colon cancer) fold higher in monolayer compared to three-dimensional multilayer cell cultures. This selectivity was related to marked differences in dFdC activation and effects on ribonucleotides.  相似文献   

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Epidemiologically linked clusters are confirmed by typing strains with molecular typing such as pulsed-field gel electrophoresis (PFGE). We compared six extended-spectrum β-lactamase producing E. coli of a PFGE-related cluster with Matrix-assisted laser desorption/ionization-time of flight mass-spectrometry based typing that confirmed relatedness faster and more cost-effective, but as reliable as PFGE.  相似文献   

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