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1.
BMC Biol ; 22(1): 30, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317114

RESUMO

BACKGROUND: Despite the increasing number of epigenomic studies in plants, little is known about the forces that shape the methylome in long-lived woody perennials. The Lombardy poplar offers an ideal opportunity to investigate the impact of the individual environmental history of trees on the methylome. RESULTS: We present the results of three interconnected experiments on Lombardy poplar. In the first experiment, we investigated methylome variability during a growing season and across vegetatively reproduced generations. We found that ramets collected over Europe and raised in common conditions have stable methylomes in symmetrical CG-contexts. In contrast, seasonal dynamics occurred in methylation patterns in CHH context. In the second experiment, we investigated whether methylome patterns of plants grown in a non-parental environment correlate with the parental climate. We did not observe a biological relevant pattern that significantly correlates with the parental climate. Finally, we investigated whether the parental environment has persistent carry-over effects on the vegetative offspring's phenotype. We combined new bud set observations of three consecutive growing seasons with former published bud set data. Using a linear mixed effects analysis, we found a statistically significant but weak short-term, parental carry-over effect on the timing of bud set. However, this effect was negligible compared to the direct effects of the offspring environment. CONCLUSIONS: Genome-wide cytosine methylation patterns in symmetrical CG-context are stable in Lombardy poplar and appear to be mainly the result of random processes. In this widespread poplar clone, methylation patterns in CG-context can be used as biomarkers to infer a common ancestor and thus to investigate the recent environmental history of a specific Lombardy poplar. The Lombardy poplar shows high phenotypic plasticity in a novel environment which enabled this clonal tree to adapt and survive all over the temperate regions of the world.


Assuntos
Adaptação Fisiológica , Epigenoma , Fenótipo , Estações do Ano , Metilação de DNA
2.
J Nurs Educ ; 61(2): 101-104, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35112947

RESUMO

BACKGROUND: Institutions may be experiencing an increasing number of applicants who are underprepared for nursing study, especially institutions with access missions. Early identification and intervention can mitigate risk of attrition and unsuccessful NCLEX-RN® outcomes. METHOD: An initial study of approximately 1,500 graduates from a multi-campus system led to the development of a comprehensive approach to student success. The model includes identifying nonacademic success factors through an early assessment survey, implementing a data-driven admissions matrix, changing progression policies, designing a new learning-relearning approach, and offering robust cocurricular student support. RESULTS: NCLEX-RN pass rates and student persistence have improved in the 4 years since implementation, and graduation rates are stable. CONCLUSION: Although improvements have been made, there is more work to do. African American students have not demonstrated overall improvements when compared to students of different racial and ethnic backgrounds. Further research is needed to test, design, and implement strategies to address social and race-related factors influencing persistence and success. [J Nurs Educ. 2022;61(2):101-104.].


Assuntos
Bacharelado em Enfermagem , Estudantes de Enfermagem , Negro ou Afro-Americano , Avaliação Educacional , Humanos , Aprendizagem , Licenciamento em Enfermagem , Estudantes
3.
Ann Palliat Med ; 11(5): 1660-1670, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34930013

RESUMO

BACKGROUND: In resource-poor countries, including in Latin American and the Caribbean, empirical information about the characteristics and incidence of medical end-of-life decisions (MELDs)-withholding or withdrawing potentially life-prolonging medical treatments-is largely absent. METHODS: The aim was to describe the incidence and decision-making characteristics of MELDs taken prior to the death of people who died at home in Trinidad and Tobago (T&T). A mortality follow-back study was used where a representative sample of deaths occurring at home in 2018 was drawn from death certificates at the national death registry. The general practitioners who certified the deaths were sent a questionnaire. RESULTS: The sample consisted of 309 adult deaths and the response rate was 31% (N=96). Physicians were: mostly male (79.2%), practiced medicine for more than twenty-years (63.5%), had no formal palliative care training (69.8%). Non-sudden deaths represented 76% (N=73), of these, medications to alleviate pain and symptoms in the last 7 days of life were administered in 65.8%, including opioids 21%. Potentially life-prolonging treatments were withheld in 9.6% but none withdrawn. No physician/patient discussions about various end-of-life treatment options occurred in 61.6%. Compared to physicians with no formal training in palliative care, those with training more often: prescribed or administered opioids in the last 7 days of life (35.7% vs. 11.1%, P=0.01), had discussions with patients about end-of-life treatment options (60.7% vs. 24.4%, P=0.002), and discussed medication use to alleviate pain and other symptoms with patients (50% vs. 17.8%, P=0.004). CONCLUSIONS: Differences in the care and treatment general practitioners provided to their patients could be associated with them having been formally trained in palliative care. The necessary support to further develop palliative care in T&T is needed.


Assuntos
Tomada de Decisões , Assistência Terminal , Adulto , Analgésicos Opioides/uso terapêutico , Tomada de Decisão Clínica , Morte , Feminino , Humanos , Masculino , Cuidados Paliativos , Inquéritos e Questionários
4.
Jt Comm J Qual Patient Saf ; 47(8): 496-502, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34120875

RESUMO

BACKGROUND: Health care providers are in a prime position to identify teens at risk for suicide, yet many do not. The research team developed and implemented a hospitalwide program to identify teens at elevated risk for suicide and connect them with services. METHODS: Screening was implemented at both locations of a pediatric hospital, including two emergency departments, three urgent care clinics, and ambulatory clinics. Patients aged 12 years and older presenting for care were screened for suicide risk using the Ask Suicide-Screening Questions (ASQ) in most settings, while the Columbia-Suicide Severity Rating Scale (C-SSRS) was used in mental health areas. A social worker responded to positive screens to complete a more thorough assessment and determine next steps. Social workers also completed outreach to patients in the weeks following a positive screen. Implementation began with pilot locations and expanded after refinements were made. Stakeholders provided screening recommendations, and education was provided prior to implementation. The cost of implementation was calculated based on the time screening required from nursing and social work. RESULTS: Review of the program focused on implementation fidelity, quality improvement, and trends among screening results. During the first year of screening, 138,598 screens were completed, and 6.8% of screens were positive for elevated risk. The annualized cost of the program was estimated to be $887,708.65 for personnel directly involved in screening and following up on positive screens. CONCLUSION: Early involvement of stakeholders and hospital leaders and a robust response plan were essential to successful implementation of this suicide-screening program.


Assuntos
Hospitais Pediátricos , Prevenção do Suicídio , Adolescente , Criança , Serviço Hospitalar de Emergência , Humanos , Programas de Rastreamento , Melhoria de Qualidade
5.
Nurs Educ Perspect ; 42(4): 205-211, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33935243

RESUMO

AIM: The aim of the study was to propose a framework, social determinants of learning™ (SDOL™), an actionable model to address learning disparities and expand learning opportunities to support nursing student diversity, equity, and inclusion. BACKGROUND: There is significant growth in the racial and ethnic diversity across students at all levels of higher education, mirroring the growing diversity of the US population. Yet, lower rates of persistence and higher attrition rates among these student groups continue. METHOD: The authors established six socially imposed forces, causative domains, as foundational to the SDOL framework. Key attributes of each domain were identified through a literature search. A case study illustrates an initial study of interventions targeting specific domains of the framework aimed toward student success. CONCLUSION: Equitable education for all has far-reaching implications across nursing education and higher education in general. Further development and testing of the SDOL framework will support the goal of equitable education for all.


Assuntos
Educação em Enfermagem , Estudantes de Enfermagem , Etnicidade , Humanos , Grupos Raciais , Determinantes Sociais da Saúde
6.
PLoS One ; 16(4): e0250698, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33914783

RESUMO

Within the HIV clinical trial field, there are gaps in existing ethical regulations in relation to post-trial care. There is need to develop post-trial care guidelines that are flexible and sensitive to local contexts and to the specific needs of different groups of participants, particularly in low income contexts. Evidence regarding HIV trial closure and post-trial care is required to underpin the development of appropriate policies in this area. This article reports research from Uganda that develops a new model of 'Facilitated Transition' to conceptualize the transition process of HIV positive trial participants from 'research' to 'usual care' health facilities after trial conclusion. This was a qualitative grounded theory study that included 21 adult HIV positive post-trial participants and 22 research staff, undertaken between October 2014 and August 2015. The findings showed that trial closure is a complex process for HIV positive participants which includes three phases: the pre-closure, trial-closure, and post-trial phases. The model highlights a range of different needs of research participants and suggests specific and person-centred interventions that can be delivered at different phases with the aim of improving health outcomes and experiences for trial participants in low income settings during trial closure. Further research needs to be done to verify the model in other contexts and for other conditions.


Assuntos
Ensaios Clínicos como Assunto , Infecções por HIV/tratamento farmacológico , Assistência ao Paciente/métodos , Humanos , Pesquisa Qualitativa
7.
Clin Transl Sci ; 14(3): 1037-1048, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33382916

RESUMO

LY2775240 is a highly selective, potent and orally-administered inhibitor of phosphodiesterase 4 (PDE4), and is being investigated as a treatment option for inflammatory disorders, such as psoriasis. LY2775240 was investigated in rodent and rhesus monkey nonclinical models. Treatment with LY2775240 led to significant reductions in TNFα production, a marker of PDE4 engagement upon immune activation, in both nonclinical models. In the first part of a 2-part first-in-human randomized study, a wide dose range of LY2775240 was safely evaluated and found to be well-tolerated with common adverse events (AEs) of nausea, diarrhea, and headache. No serious AEs were reported. The pharmacokinetic profile of LY2775240 was well-characterized, with a half-life that can support once-a-day dosing. An ex vivo pharmacodynamic (PD) assay demonstrated dose-dependent PDE4 target engagement as assessed by reduction in TNFα production. A 20 mg dose of LY2775240 led to near-maximal TNFα inhibition in this PD assay in the first part of the study and was selected for comparison with the clinical dose of apremilast (30 mg) in the crossover, second part of this study. The 20 mg dose of LY2775240 demonstrated sustained maximal (50%-80%) inhibition of TNFα over all timepoints over the 24-h duration. The comparator apremilast achieved peak inhibition of ~ 50% at only 4 h postdose with a return to about 10% inhibition within 12 h of dosing. In summary, the nonclinical data and safety, tolerability, and PK/PD data in healthy subjects supports further investigation of LY2775240 in inflammatory indications. Study Highlights WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC? Phosphodiesterase 4 (PDE4) inhibitors, such as apremilast, are currently approved to treat autoimmune disorders, such as psoriasis. LY2775240 is an oral PDE4 inhibitor being developed for treatment of a variety of inflammatory disorders. The degree of enzymatic inhibition achieved by PDE4 inhibitors clinically is poorly understood. WHAT QUESTION DID THIS STUDY ADDRESS? This study investigated single ascending doses of LY2775240, a highly selective oral PDE4 inhibitor, in healthy subjects. LY2775240 was well-tolerated over the dose range evaluated, and pharmacokinetic/pharmacodynamic (PD) profiles were well-characterized. WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE? This study evaluated different doses of LY2775240 and subsequently compared a selected LY2775240 dose with the clinical dose of apremilast with an ex vivo assay. This information builds a connection between target engagement and clinical efficacy. HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE? This is the first report of an ex vivo PD assay that has been systematically implemented in a PDE4 inhibitor Phase 1 study. Early investigation of exposure-response relationships versus a comparator can support evaluation of clinically meaningful doses of investigational agents.


Assuntos
Drogas em Investigação/farmacologia , Inibidores da Fosfodiesterase 4/farmacologia , Administração Oral , Adulto , Animais , Estudos Cross-Over , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Avaliação Pré-Clínica de Medicamentos , Drogas em Investigação/uso terapêutico , Ensaios Enzimáticos , Feminino , Voluntários Saudáveis , Humanos , Macaca mulatta , Masculino , Camundongos , Pessoa de Meia-Idade , Inibidores da Fosfodiesterase 4/uso terapêutico , Psoríase/tratamento farmacológico , Talidomida/análogos & derivados , Talidomida/farmacologia , Talidomida/uso terapêutico
8.
Assay Drug Dev Technol ; 19(1): 27-37, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33164547

RESUMO

Phenotypic screening is a neoclassical approach for drug discovery. We conducted phenotypic screening for insulin secretion enhancing agents using INS-1E insulinoma cells as a model system for pancreatic beta-cells. A principal regulator of insulin secretion in beta-cells is the metabolically regulated potassium channel Kir6.2/SUR1 complex. To characterize hit compounds, we developed an assay to quantify endogenous potassium channel activity in INS-1E cells. We quantified ligand-regulated potassium channel activity in INS-1E cells using fluorescence imaging and thallium flux. Potassium channel activity was metabolically regulated and coupled to insulin secretion. The pharmacology of channel opening agents (diazoxide) and closing agents (sulfonylureas) was used to validate the applicability of the assay. A precise high-throughput assay was enabled, and phenotypic screening hits were triaged to enable a higher likelihood of discovering chemical matter with novel and useful mechanisms of action.


Assuntos
Diazóxido/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Secretagogos/farmacologia , Compostos de Sulfonilureia/farmacologia , Receptores de Sulfonilureias/metabolismo , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos , Ensaios de Triagem em Larga Escala , Humanos , Secreção de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Imagem Óptica , Fenótipo
9.
Gut ; 70(6): 1023-1036, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33037057

RESUMO

OBJECTIVE: Dysregulated immune responses are the cause of IBDs. Studies in mice and humans suggest a central role of interleukin (IL)-23-producing mononuclear phagocytes in disease pathogenesis. Mechanistic insights into the regulation of IL-23 are prerequisite for selective IL-23 targeting therapies as part of personalised medicine. DESIGN: We performed transcriptomic analysis to investigate IL-23 expression in human mononuclear phagocytes and peripheral blood mononuclear cells. We investigated the regulation of IL-23 expression and used single-cell RNA sequencing to derive a transcriptomic signature of hyperinflammatory monocytes. Using gene network correlation analysis, we deconvolved this signature into components associated with homeostasis and inflammation in patient biopsy samples. RESULTS: We characterised monocyte subsets of healthy individuals and patients with IBD that express IL-23. We identified autosensing and paracrine sensing of IL-1α/IL-1ß and IL-10 as key cytokines that control IL-23-producing monocytes. Whereas Mendelian genetic defects in IL-10 receptor signalling induced IL-23 secretion after lipopolysaccharide stimulation, whole bacteria exposure induced IL-23 production in controls via acquired IL-10 signalling resistance. We found a transcriptional signature of IL-23-producing inflammatory monocytes that predicted both disease and resistance to antitumour necrosis factor (TNF) therapy and differentiated that from an IL-23-associated lymphocyte differentiation signature that was present in homeostasis and in disease. CONCLUSION: Our work identifies IL-10 and IL-1 as critical regulators of monocyte IL-23 production. We differentiate homeostatic IL-23 production from hyperinflammation-associated IL-23 production in patients with severe ulcerating active Crohn's disease and anti-TNF treatment non-responsiveness. Altogether, we identify subgroups of patients with IBD that might benefit from IL-23p19 and/or IL-1α/IL-1ß-targeting therapies upstream of IL-23.


Assuntos
Resistência a Medicamentos/genética , Doenças Inflamatórias Intestinais/genética , Interleucina-10/genética , Subunidade p19 da Interleucina-23/biossíntese , Subunidade p19 da Interleucina-23/genética , Monócitos/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Comunicação Autócrina , Células Cultivadas , Feminino , Expressão Gênica , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Homeostase/genética , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Interleucina-10/metabolismo , Interleucina-1alfa/metabolismo , Interleucina-1beta/metabolismo , Lipopolissacarídeos , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Comunicação Parácrina , Receptores de Interleucina-10/antagonistas & inibidores , Receptores de Interleucina-10/metabolismo , Transdução de Sinais/genética , Transcriptoma , Fator de Necrose Tumoral alfa/efeitos adversos , Adulto Jovem
10.
Ecol Evol ; 10(21): 12290-12306, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33209288

RESUMO

Habitat loss and fragmentation due to urbanization can negatively affect metapopulation persistence when gene flow among populations is reduced and population sizes decrease. Inference of patterns and processes of population connectivity derived from spatial genetic analysis has proven invaluable for conservation and management. However, a more complete account of population dynamics may be obtained by combining spatial and temporal sampling. We, therefore, performed a genetic study on European stag beetle (Lucanus cervus L.) populations in a suburban context using samples collected in three locations and during the period 2002-2016. The sampling area has seen recent landscape changes which resulted in population declines. Through the use of a suite of F ST, clustering analysis, individual assignment, and relatedness analysis, we assessed fine scale spatiotemporal genetic variation within and among habitat patches using 283 individuals successfully genotyped at 17 microsatellites. Our findings suggested the three locations to hold demographically independent populations, at least over time scales of relevance to conservation, though with higher levels of gene flow in the past. Contrary to expectation from tagging studies, dispersal appeared to be mainly female-biased. Although the life cycle of stag beetle suggests its generations to be discrete, no clear temporal structure was identified, which could be attributed to the varying duration of larval development. Since population bottlenecks were detected and estimates of effective number of breeders were low, conservation actions are eminent which should include the establishment of suitable dead wood for oviposition on both local and regional scales to increase (re)colonization success and connectivity among current populations.

11.
BMC Palliat Care ; 19(1): 123, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32795270

RESUMO

BACKGROUND: Palliative and end-of-life care development is hindered by a lack of information about the circumstances surrounding dying in developing and resource-poor countries. Our aims were to develop and obtain face and content validity for a self-administered questionnaire on end-of-life care provision and medical decision-making for use in population-based surveys. METHODS: Modelled on validated questionnaires from research in developed countries, our questionnaire was adapted to the cultural sensitivity and medico-legal context of Trinidad and Tobago. Two sets of semi-structured face-to-face cognitive interviews were done with a sample of physicians, sampling was purposive. Phase 1 assessed interpretation of the questions, terminology and content of the questionnaire. Phase 2 was tested on a heterogeneous group of physicians to identify and fix problematic questions or recurring issues. Adjustments were made incrementally and re-tested in successive interviews. RESULTS: Eighteen physicians were interviewed nationwide. Adaptations to questionnaires used in developed countries included: addition of a definition of palliative care, change of sensitive words like expedited to influenced, adjustments to question formulations, follow-up questions and answer options on medications used were added, the sequence, title and layout were changed and instructions for completion were included at the beginning of the questionnaire. CONCLUSION: A new instrument for assessing and documenting end-of-life care and circumstances of dying in a small, resource-poor Caribbean country was developed and validated, and can be readily used as a mortality follow-back instrument. Our methods and procedures of development can be applied as a guide for similar studies in other small developing countries.


Assuntos
Tomada de Decisões , Inquéritos e Questionários/normas , Assistência Terminal/estatística & dados numéricos , Adulto , Região do Caribe , Feminino , Seguimentos , Recursos em Saúde/provisão & distribuição , Humanos , Entrevistas como Assunto/métodos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Reprodutibilidade dos Testes , Inquéritos e Questionários/estatística & dados numéricos , Assistência Terminal/métodos
12.
J Res Nurs ; 25(2): 97-110, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34394613

RESUMO

BACKGROUND: Physical and psychological concerns associated with a breast cancer diagnosis continue long after treatment. Macmillan Cancer Support developed an electronic Holistic Needs Assessment (eHNA) to help identify these concerns and allow a healthcare professional to address these as part of The Recovery Package. AIMS: The study aim was to understand the women's experiences of having breast cancer, and of completing Macmillan's eHNA as part of their care. METHODS: A qualitative approach was adopted. Semi-structured interviews were undertaken with 15 women, 12-18 months following surgical treatment for invasive breast cancer. Thematic analysis identified key themes. RESULTS: Four main themes were identified in relation to experiences of the eHNA, experiences of breast cancer, coping with breast cancer and the psychological effects of surviving. Perceptions towards the eHNA varied; some women viewed the eHNA as a research tool for hospital use rather than a beneficial aspect of their care. Several participants felt unable to raise their psychological concerns on the eHNA. CONCLUSIONS: Although experiences differ, psychological issues remain a key factor for women with breast cancer, lasting long after treatment. The eHNA is not currently used to its potential or recognised by women as a tool to support their care. Further research is needed into how the eHNA can be used effectively to capture psychological concerns and determine best approaches to implementation of the tool to support individualised care.

13.
Front Plant Sci ; 11: 580653, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33519841

RESUMO

Exotic Populus taxa pose a threat to the success of riparian forest restoration in floodplain areas. We evaluated the impact of exotic Populus taxa on softwood riparian forest development along the river Common Meuse after introducing native Populus nigra and after the re-establishment of the natural river dynamics. We sampled 154 poplar seedlings that spontaneously colonized restored habitat and assessed their taxonomy based on diagnostic chloroplast and nuclear microsatellite markers. Furthermore, by using a paternity analysis on 72 seedlings resulting from six open pollinated P. nigra females, we investigated natural hybridization between frequently planted cultivated poplars and native P. nigra. The majority of the poplar seedlings from the gravel banks analyzed where identified as P. nigra; only 2% of the sampled seedlings exhibited genes of exotic poplar species. Similarly, the majority of the seedlings from the open pollinated progenies were identified as P. nigra. For three seedlings (4%), paternity was assigned to a cultivar of P. × canadensis. Almost two decades after reintroducing P. nigra, the constitution of the seed and pollen pools changed in the study area in favor of reproduction of the native species and at the expense of the exotic poplar species. This study indicates that, although significant gene flow form exotic poplars is observed in European floodplains, restoration programs of the native P. nigra can vigorously outcompete the exotic gene flows and strongly reduce the impact of exotic Populus taxa on the softwood riparian forest development.

16.
Mo Med ; 116(4): 297-302, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31527978

RESUMO

By the end of the 20th century, health care organizations worldwide were recognizing the benefits of a quick response when patients were experiencing a clinical decline and the difficulty in achieving that goal. The University of Missouri STAT Nurse program, developed in 1989, was an early innovation to deliver the "right care" at the "right time" every time. Over the years, the STAT Nurse program evolved and became the core component of a Rapid Response System. Today Rapid Response at University of Missouri Health Care is called the Targeted Interventional Group Emergency Response Team, also known as the TIGER Team after the much beloved University mascot.


Assuntos
Centros Médicos Acadêmicos , Equipe de Respostas Rápidas de Hospitais , Centros Médicos Acadêmicos/organização & administração , Deterioração Clínica , Escore de Alerta Precoce , Equipe de Respostas Rápidas de Hospitais/organização & administração , Humanos , Missouri , Sinais Vitais
18.
J Clin Endocrinol Metab ; 104(9): 3768-3778, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31120518

RESUMO

BACKGROUND: Biomarkers that predict response to anabolic therapies could expedite the development of function-promoting anabolic drugs. This study aimed to identify serum biomarkers that are responsive to testosterone administration and associated with increases in fat-free mass (FFM). METHODS: Serum samples were obtained from the 5α-Reductase Trial, a randomized trial that compared the effects of graded doses of testosterone enanthate for 20 weeks in healthy men randomized with placebo or dutasteride (dual SRD5A inhibitor). Testosterone's effects on FFM or strength measures did not differ between placebo vs dutasteride groups. Accordingly, 54 subjects treated with testosterone plus placebo were included in the discovery cohort, and 48 subjects randomized to dutasteride were included in the validation cohort. A total of 1162 biomarkers were evaluated using prespecified criteria. RESULTS: In the discovery cohort, testosterone administration increased propeptide of type III collagen (PRO-C3) and propeptide of type VI collagen (PRO-C6) levels in a dose- and concentration-dependent manner; increases in these biomarkers from baseline to week 12 were associated with changes in FFM from baseline to week 20 (PRO-C3: r2 = 0.437, P < 0.001; PRO-C6: r2 = 0.434, P < 0.001). Changes in PRO-C3 and PRO-C6 levels were significantly associated with changes in chest press strength (PRO-C3: r2 = 0.394, P < 0.001; PRO-C6: r2 = 0.530, P < 0.001). In the SOMAscan, changes in IGF binding protein-6 (IGFBP6) and glypican 3 (GPC3) were associated with changes in total and free testosterone levels and FFM. These findings were replicated in the Validation cohort. CONCLUSION: PRO-C3, PRO-C6, IGFBP6, and GPC3 fulfilled the prespecified criteria for biomarkers of testosterone-induced muscle anabolism. Changes in these biomarkers were associated with changes in total and free testosterone concentrations and with testosterone-induced gains in FFM.

20.
PLoS One ; 14(4): e0215860, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31022224

RESUMO

Lucanus cervus (L.), the stag beetle, is a saproxylic beetle species distributed widely across Europe. Throughout its distribution the species has exhibited pronounced declines and is widely considered threatened. Conservation efforts may be hindered by the lack of population genetic data and understanding of the spatial scale of population connectivity. To address this knowledge gap this research details the first broad scale phylogeographic study of L. cervus based on mitochondrial DNA (mtDNA) sequencing and microsatellite analysis of samples collected from 121 localities across Europe. Genetic data were complemented by palaeo-distribution models of spatial occupancy during the Last Glacial Maximum to strengthen inferences of refugial areas. A salient feature of the mtDNA was the identification of two lineages. Lineage I was widespread across Europe while lineage II was confined to Greece. Microsatellites supported the differentiation of the Greek samples and alongside palaeo-distribution models indicated this area was a glacial refuge. The genetic endemism of the Greek samples, and demographic results compatible with no signatures of spatial expansion likely reflects restricted dispersal into and out of the area. Lineage I exhibited a shallow star like phylogeny compatible with rapid population expansion across Europe. Demographic analysis indicated such expansions occurred after the Last Glacial Maximum. Nuclear diversity and hindcast species distribution models indicated a central Italian refuge for lineage I. Palaeo-distribution modelling results also suggested a western refuge in northern Iberia and south-west France. In conclusion the results provide evidence of glacial divergence in stag beetle while also suggesting high, at least on evolutionary timescales, gene flow across most of Europe. The data also provide a neutral genetic framework against which patterns of phenotypic variation may be assessed.


Assuntos
Besouros/classificação , Ecossistema , Modelos Teóricos , Filogeografia , Animais , Teorema de Bayes , Besouros/genética , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Variação Genética , Genética Populacional , Haplótipos/genética , Repetições de Microssatélites/genética , Paleontologia , Análise de Componente Principal , Especificidade da Espécie
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