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1.
Cell ; 171(6): 1437-1452.e17, 2017 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-29195078

RESUMO

We previously piloted the concept of a Connectivity Map (CMap), whereby genes, drugs, and disease states are connected by virtue of common gene-expression signatures. Here, we report more than a 1,000-fold scale-up of the CMap as part of the NIH LINCS Consortium, made possible by a new, low-cost, high-throughput reduced representation expression profiling method that we term L1000. We show that L1000 is highly reproducible, comparable to RNA sequencing, and suitable for computational inference of the expression levels of 81% of non-measured transcripts. We further show that the expanded CMap can be used to discover mechanism of action of small molecules, functionally annotate genetic variants of disease genes, and inform clinical trials. The 1.3 million L1000 profiles described here, as well as tools for their analysis, are available at https://clue.io.


Assuntos
Perfilação da Expressão Gênica/métodos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Perfilação da Expressão Gênica/economia , Humanos , Neoplasias/tratamento farmacológico , Especificidade de Órgãos , Preparações Farmacêuticas/metabolismo , Análise de Sequência de RNA/economia , Análise de Sequência de RNA/métodos , Bibliotecas de Moléculas Pequenas
2.
Bioinformatics ; 37(18): 2889-2895, 2021 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-33824954

RESUMO

MOTIVATION: Do machine learning methods improve standard deconvolution techniques for gene expression data? This article uses a unique new dataset combined with an open innovation competition to evaluate a wide range of approaches developed by 294 competitors from 20 countries. The competition's objective was to address a deconvolution problem critical to analyzing genetic perturbations from the Connectivity Map. The issue consists of separating gene expression of individual genes from raw measurements obtained from gene pairs. We evaluated the outcomes using ground-truth data (direct measurements for single genes) obtained from the same samples. RESULTS: We find that the top-ranked algorithm, based on random forest regression, beat the other methods in accuracy and reproducibility; more traditional gaussian-mixture methods performed well and tended to be faster, and the best deep learning approach yielded outcomes slightly inferior to the above methods. We anticipate researchers in the field will find the dataset and algorithms developed in this study to be a powerful research tool for benchmarking their deconvolution methods and a resource useful for multiple applications. AVAILABILITY AND IMPLEMENTATION: The data is freely available at clue.io/data (section Contests) and the software is on GitHub at https://github.com/cmap/gene_deconvolution_challenge. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Algoritmos , Software , Reprodutibilidade dos Testes , Algoritmo Florestas Aleatórias , Biologia
3.
Depress Anxiety ; 39(10-11): 675-685, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35621368

RESUMO

Trauma-focused guided self-help (TF-GSH) is an important alternative to psychological therapy delivered by a therapist. This meta-analysis evaluates the efficacy of TF-GSH in reducing posttraumatic stress disorder  (PTSD) symptoms and comorbid depressive and anxiety symptoms. A total of 17 trials were included that compared a TF-GSH intervention (N = 610) to various control comparators (N = 570). Control conditions included treatment as usual (k = 2), waiting list (k = 11), phone monitoring (k = 1), nontrauma writing (k = 1), general support (k = 1), and supportive counseling (k = 1). A moderate- to large-sized effect favouring TF-GSH was observed for PTSD (k = 17, g = -0.81, 95% confidence interval [CI]: -1.24, -0.39) and a moderate-sized effect was observed for depressive (k = 13, g = -0.73, 95% CI: -1.16, -0.31) and anxiety (k = 11, g = -0.72, 95% CI: -1.18, -0.27) symptoms, with considerable heterogeneity. Moderator analyses were all not statistically significant. Results indicate that TF-GSH is a promising treatment for PTSD and comorbid depressive and anxiety symptoms. We discuss the nature, extent, and quality of the literature to provide a point of departure for future research. TF-GSH (and unguided self-help) may not be appropriate for certain individuals at certain times. Exploring a broad range of treatment delivery modalities will move the field closer towards a model of evidence-based care in which the likely appropriate dose and type of intervention can be matched to individuals based on presenting problems and other variables.


Assuntos
Terapia Cognitivo-Comportamental , Transtornos de Estresse Pós-Traumáticos , Ansiedade/terapia , Transtornos de Ansiedade/terapia , Terapia Cognitivo-Comportamental/métodos , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/terapia
4.
Ecol Indic ; 141: 109046, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35991319

RESUMO

Anthropogenic alteration of physical habitat structure in streams and rivers is increasingly recognized as a major cause of impairment worldwide. As part of their assessment of the status and trends in the condition of rivers and streams in the U.S., the U.S. Environmental Protection Agency's (USEPA) National Aquatic Resource Surveys (NARS) quantify and monitor channel size and slope, substrate size and stability, instream habitat complexity and cover, riparian vegetation cover and structure, anthropogenic disturbance activities, and channel-riparian interaction. Like biological assemblages and water chemistry, physical habitat is strongly controlled by natural geoclimatic factors that can obscure or amplify the influence of human activities. We developed a systematic approach to estimate the deviation of observed river and stream physical habitat from that expected in least-disturbed reference conditions. We applied this approach to calculate indices of anthropogenic alteration of three aspects of physical habitat condition in the conterminous U.S. (CONUS): streambed sediment size and stability, riparian vegetation cover, and instream habitat complexity. The precision and responsiveness of these indices led the USEPA to use them to evaluate physical habitat condition in CONUS rivers and streams. The scores of these indices systematically decreased with greater anthropogenic disturbance at river and stream sites in the CONUS and within ecoregions, which we interpret as a response of these physical habitat indices to anthropogenic influences. Although anthropogenic activities negatively influenced all three physical habitat indices in the least-disturbed sites within most ecoregions, natural geoclimatic and geomorphic factors were the dominant influences. For sites over the full range of anthropogenic disturbance, analyses of observed/expected sediment characteristics showed augmented flood flows and basin and riparian agriculture to be the leading predictors of streambed instability and excess fine sediments. Similarly, basin and riparian agriculture and non-agricultural riparian land uses were the leading predictors of reduced riparian vegetation cover complexity in the CONUS and within ecoregions. In turn, these reductions in riparian vegetation cover and complexity, combined with reduced summer low flows, were the leading predictors of instream habitat simplification. We conclude that quantitative measures of physical habitat structure are useful and important indicators of the impacts of human activities on stream and river condition.

5.
Ecol Indic ; 141: 109047, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35991318

RESUMO

Rigorous assessments of the ecological condition of water resources and the effect of human activities on those waters require quantitative physical, chemical, and biological data. The U.S. Environmental Protection Agency's river and stream surveys quantify river and stream bed particle size and stability, instream habitat complexity and cover, riparian vegetation cover and structure, and anthropogenic disturbance activities. Physical habitat is strongly controlled by natural geoclimatic factors that co-vary with human activities. We expressed the anthropogenic alteration of physical habitat as O/E ratios of observed habitat metric values divided by values expected under least-disturbed reference conditions, where site-specific expected values vary given their geoclimatic and geomorphic context. We set criteria for good, fair, and poor condition based on the distribution of O/E values in regional least-disturbed reference sites. Poor conditions existed in 22-24% of the 1.2 million km of streams and rivers in the conterminous U.S. for riparian human disturbance, streambed sediment and riparian vegetation cover, versus 14% for instream habitat complexity. Based on the same four indicators, the percentage of stream length in poor condition within 9 separate U.S. ecoregions ranged from 4% to 42%. Associations of our physical habitat indices with anthropogenic pressures demonstrate the scope of anthropogenic habitat alteration; habitat condition was negatively related to the level of anthropogenic disturbance nationally and in nearly all ecoregions. Relative risk estimates showed that streams and rivers with poor sediment, riparian cover complexity, or instream habitat cover conditions were 1.4 to 2.6 times as likely to also have fish or macroinvertebrate assemblages in poor condition. Our physical habitat condition indicators help explain deviations in biological conditions from those observed among least-disturbed sites and inform management actions for rehabilitating impaired waters and mitigating further ecological degradation.

6.
Ecol Indic ; 141: 1-13, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36003067

RESUMO

Taxonomic inconsistency in species-level identifications has constrained use of diatoms as biological indicators in aquatic assessments. We addressed this problem by developing diatom multimetric indices (MMIs) of ecological condition using genus-level taxonomy and trait-based autecological information. The MMIs were designed to assess river and stream chemical, physical and biological condition across the conterminous United States. Trait-based approaches have the advantage of using both species-level and genus-level data, which require less effort and expense to acquire than traditional species-based approaches and eliminate the persistent taxonomic biases introduced over vast geographic extents. For large-extent assessment programs that require multiple taxonomic laboratories to process samples, such as the United States Environmental Protection Agency's (U.S. EPA's) National Rivers and Streams Assessment (NRSA), the trait approach can eliminate discrepancies in species-level identification or nomenclature that hinder diatom data interpretation. We developed trait-based MMIs using NRSA data for each of the three large ecoregions across the U.S. - the East, Plains, and West. All three MMIs performed well in discriminating least-disturbed from most-disturbed sites. The MMI for the East had the greatest discrimination ability, followed by MMIs for the Plains and West, respectively. The performance of the MMIs was comparable to that observed in existing NRSA fish and macroinvertebrate MMIs. Our research shows that trait-based diatom indices constructed on genus-level taxonomy can be effective for large-scale assessments, and may also allow programs such as NRSA to assess trends in freshwater condition retrospectively, by revisiting older diatom datasets. Moreover, our genus-based approach facilitates including of diatoms into other assessment programs that have limited monitoring resources.

7.
Medicina (Kaunas) ; 58(2)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35208577

RESUMO

Background and Objectives: Coronavirus disease 19 (COVID-19) has emerged as the most devastating syndemic of the 21st century, with worrisome and sustained consequences for the entire society. Despite the relative success of vaccination programs, the global threat of the novel coronavirus SARS-CoV-2 is still present and further efforts are needed for its containment and control. Essential for its control and containment is getting closer to understanding the actual extent of SARS-CoV-2 infections. Material and Methods: We present a model based on the mortality data of Kazakhstan for the estimation of the underlying epidemic dynamic-with both the lag time from infection to death and the infection fatality rate. For the estimation of the actual number of infected individuals in Kazakhstan, we used both back-casting and capture-recapture methods. Results: Our results suggest that despite the increased testing capabilities in Kazakhstan, official case reporting undercounts the number of infections by at least 60%. Even though our count of deaths may be either over or underestimated, our methodology could be a more accurate approach for the following: the estimation of the actual magnitude of the pandemic; aiding the identification of different epidemiological values; and reducing data bias. Conclusions: For optimal epidemiological surveillance and control efforts, our study may lead to an increased awareness of the effect of COVID-19 in this region and globally, and aid in the implementation of more effective screening and diagnostic measures.


Assuntos
COVID-19 , Humanos , Cazaquistão/epidemiologia , Pandemias/prevenção & controle , SARS-CoV-2
8.
Fish Res ; 223: 105749, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34334849

RESUMO

Sport fishing is an important recreational and economic activity, especially in Australia, Europe and North America, and the condition of sport fish populations is a key ecological indicator of water body condition for millions of anglers and the public. Despite its importance as an ecological indicator representing the status of sport fish populations, an index for measuring this ecosystem service has not been quantified by analyzing actual fish taxa, size and abundance data across the U.S.A. Therefore, we used game fish data collected from 1,561 stream and river sites located throughout the conterminous U.S.A. combined with specific fish species and size dollar weights to calculate site-specific recreational fishery index (RFI) scores. We then regressed those scores against 38 potential site-specific environmental predictor variables, as well as site-specific fish assemblage condition (multimetric index; MMI) scores based on entire fish assemblages, to determine the factors most associated with the RFI scores. We found weak correlations between RFI and MMI scores and weak to moderate correlations with environmental variables, which varied in importance with each of 9 ecoregions. We conclude that the RFI is a useful indicator of a stream ecosystem service, which should be of greater interest to the USA public and traditional fishery management agencies than are MMIs, which tend to be more useful for ecologists, environmentalists and environmental quality agencies.

9.
Limnologica ; 87: 125859, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34017150

RESUMO

Fish species richness is an indicator of river ecological condition but it is particularly difficult to estimate in large unwadeable rapidly flowing rivers. Intensive multi-gear sampling is time consuming, logistically complex and expensive. However, insufficient sampling effort underestimates species richness and yields inaccurate data about the ecological condition of river sites. We raft-electrofished 10 river sites in 10 different ecoregions and six western USA states for distances equal to 300 times their mean wetted channel widths (MCWs) to estimate the effort needed to approach asymptotes in fish species richness. To collect 90% of the observed fish species at the sites, we found that an average of 150 MCWs (ranging 80-210 MCWs) were needed, with the number of MCWs increasing in rivers with a higher proportion of spatially rare species. Frequently, the second or third additional 100 MCWs produced only one or two additional singletons or doubletons (species occurring only once or twice at a site). Before initiating sampling programs for adequately estimating species richness, we recommend assessing sampling effort, particularly if rare or uncommon species are expected or desired.

10.
Ecol Indic ; 1122020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33628123

RESUMO

National and regional ecological assessments are essential for making rational decisions concerning water body conservation and management at those spatial extents. We analyzed data from 4597 samples collected from 3420 different sites across the conterminous USA during the U.S. Environmental Protection Agency's 2008-2009 and 2013-2014 National Rivers and Streams Assessment. We evaluated the relationship between both fish and macroinvertebrate multimetric index (MMI) condition scores and 38 environmental factors to assess the relative importance of natural versus anthropogenic predictors, contrast site-scale versus watershed-scale predictors, and examine ecoregional and assemblage differences. We found that most of the environmental factors we examined were related to either fish and/or macroinvertebrate MMI scores in some fashion and that the factors involved, and strength of the relationship, varied by ecoregion and between assemblages. Factors more associated with natural conditions were usually less important in explaining MMI scores than factors more directly associated with anthropogenic disturbances. Local site-scale factors explained more variation than watershed-scale factors. Random forest and multiple regression models performed similarly, and the fish MMI-environment relationships were stronger than macroinvertebrate MMI-environment relationships. Among ecoregions, the strongest environmental relationships were observed in the Northern Appalachians and the weakest in the Southern Plains. The fish and macroinvertebrate MMIs were only weakly correlated with each other, and they generally responded more strongly to different groups of variables. These results support the use of multiple assemblages and the sampling of multiple environmental indicators in ecological assessments across large spatial extents.

11.
Ecol Indic ; 85: 1133-1148, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29628801

RESUMO

Watershed integrity is the capacity of a watershed to support and maintain the full range of ecological processes and functions essential to sustainability. Using information from EPA's StreamCat dataset, we calculated and mapped an Index of Watershed Integrity (IWI) for 2.6 million watersheds in the conterminous US with first-order approximations of relationships between stressors and six watershed functions: hydrologic regulation, regulation of water chemistry, sediment regulation, hydrologic connectivity, temperature regulation, and habitat provision. Results show high integrity in the western US, intermediate integrity in the southern and eastern US, and the lowest integrity in the temperate plains and lower Mississippi Valley. Correlation between the six functional components was high (r = 0.85-0.98). A related Index of Catchment Integrity (ICI) was developed using local drainages of individual stream segments (i.e., excluding upstream information). We evaluated the ability of the IWI and ICI to predict six continuous site-level indicators with regression analyses - three biological indicators and principal components derived from water quality, habitat, and combined water quality and habitat variables - using data from EPA's National Rivers and Streams Assessment. Relationships were highly significant, but the IWI only accounted for 1-12% of the variation in the four biological and habitat variables. The IWI accounted for over 25% of the variation in the water quality and combined principal components nationally, and 32-39% in the Northern and Southern Appalachians. We also used multinomial logistic regression to compare the IWI with the categorical forms of the three biological indicators. Results were consistent: we found positive associations but modest results. We compared how the IWI and ICI predicted the water quality PC relative to agricultural and urban land use. The IWI or ICI are the best predictors of the water quality PC for the CONUS and six of the nine ecoregions, but they only perform marginally better than agriculture in most instances. However, results suggest that agriculture would not be appropriate in all parts of the country, and the index is meant to be responsive to all stressors. The IWI in its present form (available through the StreamCat website; https://www.epa.gov/national-aquatic-resource-surveys/streamcat) could be useful for management efforts at multiple scales, especially when combined with information on site condition. The IWI could be improved by incorporating empirical or literature-derived relationships between functional components and stressors. However, limitations concerning the absence of data for certain stressors should be considered.

13.
Am Fam Physician ; 95(12): 779-784, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28671425

RESUMO

Slipped capital femoral epiphysis (SCFE) is the most common hip disorder in adolescents, occurring in 10.8 per 100,000 children. SCFE usually occurs in those eight to 15 years of age and is one of the most commonly missed diagnoses in children. SCFE is classified as stable or unstable based on the stability of the physis. It is associated with obesity, growth spurts, and (occasionally) endocrine abnormalities such as hypothyroidism, growth hormone supplementation, hypogonadism, and panhypopituitarism. Patients with SCFE usually present with limping and poorly localized pain in the hip, groin, thigh, or knee. Diagnosis is confirmed by bilateral hip radiography, which should include anteroposterior and frog-leg views in patients with stable SCFE, and anteroposterior and cross-table lateral views in unstable SCFE. The goals of treatment are to prevent slip progression and avoid complications such as avascular necrosis, chondrolysis, and femoroacetabular impingement. Stable SCFE is usually treated using in situ screw fixation. Treatment of unstable SCFE also usually involves in situ fixation, but there is controversy about timing of surgery and the value of reduction. Postoperative rehabilitation of patients with SCFE may follow a five-phase protocol.


Assuntos
Epifise Deslocada/diagnóstico , Adolescente , Parafusos Ósseos , Criança , Diagnóstico Diferencial , Epifise Deslocada/diagnóstico por imagem , Epifise Deslocada/cirurgia , Humanos
14.
Environ Sci Technol ; 50(7): 3409-15, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-26914108

RESUMO

We describe continental-scale increases in lake and stream total phosphorus (TP) concentrations, identified through periodic probability surveys of thousands of water bodies in the conterminous U.S. The increases, observed over the period 2000-2014 were most notable in sites in relatively undisturbed catchments and where TP was initially low (e.g., less than 10 µg L(-1)). Nationally, the percentage of stream length in the U.S. with TP ≤ 10 µg L(-1) decreased from 24.5 to 10.4 to 1.6% from 2004 to 2009 to 2014; the percentage of lakes with TP ≤ 10 µg L(-1) decreased from 24.9 to 6.7% between 2007 and 2012. Increasing TP concentrations appear to be ubiquitous, but their presence in undeveloped catchments suggests that they cannot be entirely attributed to either point or common non-point sources of TP.


Assuntos
Lagos , Fósforo/análise , Rios , Monitoramento Ambiental/métodos , Lagos/análise , Lagos/química , Rios/química , Estados Unidos
15.
BMC Plant Biol ; 14: 100, 2014 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-24742262

RESUMO

BACKGROUND: The nematode Pratylenchus neglectus has a wide host range and is able to feed on the root systems of cereals, oilseeds, grain and pasture legumes. Under the Mediterranean low rainfall environments of Australia, annual Medicago pasture legumes are used in rotation with cereals to fix atmospheric nitrogen and improve soil parameters. Considerable efforts are being made in breeding programs to improve resistance and tolerance to Pratylenchus neglectus in the major crops wheat and barley, which makes it vital to develop appropriate selection tools in medics. RESULTS: A strong source of tolerance to root damage by the root lesion nematode (RLN) Pratylenchus neglectus had previously been identified in line RH-1 (strand medic, M. littoralis). Using RH-1, we have developed a single seed descent (SSD) population of 138 lines by crossing it to the intolerant cultivar Herald. After inoculation, RLN-associated root damage clearly segregated in the population. Genetic analysis was performed by constructing a genetic map using simple sequence repeat (SSR) and gene-based SNP markers. A highly significant quantitative trait locus (QTL), QPnTolMl.1, was identified explaining 49% of the phenotypic variation in the SSD population. All SSRs and gene-based markers in the QTL region were derived from chromosome 1 of the sequenced genome of the closely related species M. truncatula. Gene-based markers were validated in advanced breeding lines derived from the RH-1 parent and also a second RLN tolerance source, RH-2 (M. truncatula ssp. tricycla). Comparative analysis to sequenced legume genomes showed that the physical QTL interval exists as a synteny block in Lotus japonicus, common bean, soybean and chickpea. Furthermore, using the sequenced genome information of M. truncatula, the QTL interval contains 55 genes out of which five are discussed as potential candidate genes responsible for the mapped tolerance. CONCLUSION: The closely linked set of SNP-based PCR markers is directly applicable to select for two different sources of RLN tolerance in breeding programs. Moreover, genome sequence information has allowed proposing candidate genes for further functional analysis and nominates QPnTolMl.1 as a target locus for RLN tolerance in economically important grain legumes, e.g. chickpea.


Assuntos
Adaptação Fisiológica/genética , Medicago/genética , Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Raízes de Plantas/genética , Raízes de Plantas/parasitologia , Tylenchoidea/fisiologia , Animais , Biomassa , Cruzamento , Mapeamento Cromossômico , Cruzamentos Genéticos , Ligação Genética , Marcadores Genéticos , Fenótipo , Brotos de Planta/genética , Locos de Características Quantitativas/genética , Reprodutibilidade dos Testes , Sementes/genética
16.
Integr Comp Biol ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587825

RESUMO

The "adaptive sterilization hypothesis" argues that the tendency of sexually transmitted infections (STIs) to cause infertility likely reflects an evolutionary adaptation of these pathogens. For example, some STIs can lead to bilateral occlusions of the oviducts and sterile matings. Cycling females that do not spend time gestating and lactating are ready to mate sooner than fertile females, and therefore, likely to mate more frequently and possibly more promiscuously. These sexual activities are associated with enhanced transmissibility of STIs, and tubal occlusion is a proximate mechanism by which STIs can increase fitness. Our principal objectives were to determine whether female mice inoculated with Chlamydia muridarum mate more frequently than mice inoculated with sterile saline and to test the hypothesis that tubal occlusion following C. muridarum infection modulates mating behavior in a manner that might increase transmissibility of Chlamydia. Similar to C. trachomatis infections in human females, C. muridarum can ascend the reproductive tract of mice, damage and occlude the oviducts, and cause infertility. However, ovarian function and mating activity are maintained following tubal occlusion. Twenty C57Bl/6 mice with regular estrous cycles were given intra-vaginal inocula of C. muridarum and 32 days later paired with a male for 90 days. Nine saline-treated females served as controls. Three Chlamydia-inoculated females were rendered infertile due to bilateral oviductal damage and mated 8 (±0.0) times. Control females mated on average 4.6 (±0.3) times, and 17 Chlamydia-inoculated fertile females, including six females with only a single oviduct occluded, mated on average 4.7 (±0.2) times. Chlamydia-inoculated fertile females with unilateral oviductal damage had significantly smaller average litter sizes as compared to females inoculated with saline. Females with unilateral tubal occlusion also tended to wean fewer pups than saline controls over the course of 90 days. Female mice with Chlamydia-induced tubal infertility mated more frequently (approximately every 11 d) than did fertile females (approximately every 20 d), which is consistent with the adaptive sterilization hypothesis. To determine whether Chlamydia-induced sterilization is truly adaptive, future studies will need to demonstrate increased sexual transmissibility, and possibly increased promiscuity, within populations of freely breeding mice.

17.
BMC Plant Biol ; 13: 54, 2013 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-23531152

RESUMO

BACKGROUND: Medicago truncatula Gaertn. (barrel medic) is cultivated as a pasture legume for its high protein content and ability to improve soils through nitrogen fixation. Toxic concentrations of the micronutrient Boron (B) in agricultural soils hamper the production of cereal and leguminous crops. In cereals, the genetic analysis of B tolerance has led to the development of molecular selection tools to introgress and maintain the B tolerance trait in breeding lines. There is a comparable need for selection tools in legumes that grow on these toxic soils, often in rotation with cereals. RESULTS: Genetic variation for B tolerance in Medicago truncatula was utilised to generate two F2 populations from crosses between tolerant and intolerant parents. Phenotyping under B stress revealed a close correlation between B tolerance and biomass production and a segregation ratio explained by a single dominant locus. M. truncatula homologues of the Arabidopsis major intrinsic protein (MIP) gene AtNIP5;1 and the efflux-type transporter gene AtBOR1, both known for B transport, were identified and nearby molecular markers screened across F2 lines to verify linkage with the B-tolerant phenotype. Most (95%) of the phenotypic variation could be explained by the SSR markers h2_6e22a and h2_21b19a, which flank a cluster of five predicted MIP genes on chromosome 4. Three CAPS markers (MtBtol-1,-2,-3) were developed to dissect the region further. Expression analysis of the five predicted MIPs indicated that only MtNIP3 was expressed when leaf tissue and roots were assessed. MtNIP3 showed low and equal expression in the roots of tolerant and intolerant lines but a 4-fold higher expression level in the leaves of B-tolerant cultivars. The expression profile correlates closely with the B concentration measured in the leaves and roots of tolerant and intolerant plants. Whereas no significant difference in B concentration exists between roots of tolerant and intolerant plants, the B concentration in the leaves of tolerant plants is less than half that of intolerant plants, which further supports MtNIP3 as the best candidate for the tolerance trait-defining gene in Medicago truncatula. CONCLUSION: The close linkage of the MtNIP3 locus to B toxicity tolerance provides a source of molecular selection tools to pasture breeding programs. The economical importance of the locus warrants further investigation of the individual members of the MIP gene cluster in other pasture and in grain legumes.


Assuntos
Boro/metabolismo , Medicago truncatula/genética , Medicago truncatula/metabolismo , Proteínas de Plantas/genética , Boro/toxicidade , Regulação da Expressão Gênica de Plantas , Ligação Genética , Fenótipo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo
18.
J Cardiovasc Nurs ; 28(6): 550-62, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23047474

RESUMO

BACKGROUND: Coronary heart disease (CHD) risk factor reduction is required to maximize the benefits to be gained from coronary artery bypass grafting. Risk factor reduction after surgery, however, is often incomplete and adherence rates are poor. The health behaviors of the cardiac partner can be supportive or can act to undermine the patient's motivation for change in risk factors. Concordance in health behaviors in couples can make it more difficult for patients to engage in positive lifestyle changes. OBJECTIVES: The aims of this study were to increase understanding of the role of concordance in CHD risk factors and common medical conditions in patients and partners before and 4 months after bypass grafting and to examine changes in the pattern of concordance over time. METHODS: A prospective study of patients' and partners' CHD risk factors was conducted in the outpatient clinic before and at home 4 months after bypass grafting. RESULTS: There was significant concordance for preoperative physical activity, body mass index, and diabetes mellitus, and postoperatively, there was significant concordance for smoking status, physical activity, body mass index, cholesterol, and diabetes mellitus. There were significant associations between patients' preoperative and postoperative physical activity and cholesterol and between the partners' preoperative and postoperative physical activity. There was a significant change in the pattern of concordance for physical activity from preoperation to postoperation, with more patients but not partners increasing their physical activity levels. CONCLUSIONS: Results revealed significant concordance in CHD risk factors and common medical conditions in patients and partners before and 4 months after coronary artery bypass grafting. This indicates that the behaviors of some couples can make it more difficult for patients to change their lifestyle. The health professionals involved in educating patients before and after bypass grafting need to target the patient and partner as a couple to help achieve more successful risk factor reduction.


Assuntos
Ponte de Artéria Coronária , Doença das Coronárias/cirurgia , Comportamentos Relacionados com a Saúde , Estilo de Vida , Cônjuges , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Adulto Jovem
19.
BMC Nurs ; 12(1): 16, 2013 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-23829859

RESUMO

BACKGROUND: Patients having coronary artery bypass grafting (CABG) often depend on their partners for assistance before and after surgery. Whilst patients' physical and mental health usually improves after surgery little is known about the partners' health-related quality of life (HRQoL) in CABG. If the partners' physical and emotional health is poor this can influence their caregiving role and ability to support the patient. This study aimed: to increase understanding of patients' and partners' HRQoL before and after CABG; to explore whether patients' and partners' pre-operative socio-demographics and HRQoL predict their own, and also partners' HRQoL 4 months after CABG. METHODS: This prospective study recruited 84 dyads (patients 84% males, aged 64.5 years; partners 94% females, aged 61.05 years). Patients' and partners' perceived health status was assessed using the Short-Form 12 Health Survey. Patients' physical limitation, angina symptoms and treatment satisfaction were assessed using the Seattle Angina Questionnaire. Partners' emotional, physical and social functioning was assessed using the Quality of Life of Cardiac Spouses Questionnaire. Data were analysed using hierarchical multiple (logistic) regressions, repeated measures analysis of variance, paired t test and Chi square. RESULTS: Patients most likely to have poorer physical health post-operatively were associated with partners who had poorer pre-operative physical health. Partners most likely to have poorer emotional, physical and social functioning post-operatively were associated with patients who had poorer pre-operative mental health. Patients" and partners' poorer post-operative HRQoL was also explained by their poorer pre-operative HRQoL. CONCLUSION: The partners' involvement should be considered as part of patients' pre-operative assessment. Special attention needs be paid to patients' pre-operative mental health since it is likely to impact on their post-operative mental health and the partner's emotional, physical and social functioning.

20.
Knowl Manag Aquat Ecosyst ; 424(19): 1-16, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37593206

RESUMO

Both native and non-native taxa richness patterns are useful for evaluating areas of greatest conservation concern. To determine those patterns, we analyzed fish and macroinvertebrate taxa richness data obtained at 3475 sites collected by the USEPA's National Rivers and Streams Assessment. We also determined which natural and anthropogenic variables best explained patterns in regional richness. Macroinvertebrate and fish richness increased with the number of sites sampled per region. Therefore, we determined residual taxa richness from the deviation of observed richness from predicted richness given the number of sites per region. Regional richness markedly exceeded average site richness for both macroinvertebrates and fish. Predictors of macroinvertebrate-genus and fish-species residual-regional richness differed. Air temperature was an important predictor in both cases but was positive for fish and negative for macroinvertebrates. Both natural and land use variables were significant predictors of regional richness. This study is the first to determine mean site and regional richness of both fish and aquatic macroinvertebrates across the conterminous USA, and the key anthropogenic drivers of regional richness. Thus, it offers important insights into regional USA biodiversity hotspots.

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