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1.
J AAPOS ; : 103934, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38763855
2.
New Phytol ; 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38655662

RESUMEN

Climate change is simultaneously increasing carbon dioxide concentrations ([CO2]) and temperature. These factors could interact to influence plant physiology and performance. Alternatively, increased [CO2] may offset costs associated with elevated temperatures. Furthermore, the interaction between elevated temperature and [CO2] may differentially affect populations from along an elevational gradient and disrupt local adaptation. We conducted a multifactorial growth chamber experiment to examine the interactive effects of temperature and [CO2] on fitness and ecophysiology of diverse accessions of Boechera stricta (Brassicaceae) sourced from a broad elevational gradient in Colorado. We tested whether increased [CO2] would enhance photosynthesis across accessions, and whether warmer conditions would depress the fitness of high-elevation accessions owing to steep reductions in temperature with increasing elevation in this system. Elevational clines in [CO2] are not as evident, making it challenging to predict how locally adapted ecotypes will respond to elevated [CO2]. This experiment revealed that elevated [CO2] increased photosynthesis and intrinsic water use efficiency across all accessions. However, these instantaneous responses to treatments did not translate to changes in fitness. Instead, increased temperatures reduced the probability of reproduction for all accessions. Elevated [CO2] and increased temperatures interacted to shift the adaptive landscape, favoring lower elevation accessions for the probability of survival and fecundity. Our results suggest that elevated temperatures and [CO2] associated with climate change could have severe negative consequences, especially for high-elevation populations.

3.
Ann Bot ; 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38606950

RESUMEN

BACKGROUND: Pollinators impose strong selection on floral traits. Indeed, pollinator syndromes are the result of these strong selective forces, but other abiotic and biotic agents also drive the evolution of floral traits and influence plant reproduction. Global change is expected to have widespread effects on biotic and abiotic systems resulting in novel selection on floral traits under future conditions. SCOPE: Global change has depressed pollinator abundance and altered abiotic conditions, thereby exposing flowering plant species to novel suites of selective pressures. Here we consider how biotic and abiotic factors interact to shape the expression and evolution of various floral characteristics (the targets of selection), including floral size, color, physiology, reward quantity and quality, and longevity amongst other traits. We examine cases in which selection imposed by climatic factors conflicts with pollinator-mediated selection. Additionally, we explore how floral traits respond to environmental changes through phenotypic plasticity and how that can alter plant fecundity. In this review, we evaluate how global change may shift the expression and evolution of floral phenotypes. CONCLUSIONS: Floral traits evolve in response to multiple interacting agents of selection. Different agents can sometimes exert conflicting selection. For example, pollinators often prefer large flowers, but drought stress can favor the evolution of smaller flowers, and the size of floral organs can evolve as a trade-off between selection mediated by these opposing actors. Nevertheless, few studies have factorially manipulated abiotic and biotic agents of selection to disentangle their relative strengths and directions of selection. The literature has more often evaluated plastic responses of floral traits to stressors than it has considered how abiotic factors alter selection on these traits. Furthermore, global change will likely alter the selective landscape through changes in the abundance and community compositions of mutualists and antagonists and novel abiotic conditions. We encourage future work to consider a more holistic model of floral evolution, which will enable more robust predictions about floral evolution and plant reproduction as global change progresses.

4.
Gynecol Oncol ; 181: 1-7, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38096673

RESUMEN

OBJECTIVE: To describe the participation of racial and ethnic minority groups (REMGs) in gynecologic oncology trials. METHODS: Gynecologic oncology studies registered on ClinicalTrials.gov between 2007 and 2020 were identified. Trials with published results were analyzed based on reporting of race/ethnicity in relation to disease site and trial characteristics. Expected enrollment by race/ethnicity was calculated and compared to actual enrollment, adjusted for 2010 US Census population data. RESULTS: 2146 gynecologic oncology trials were identified. Of published trials (n = 252), 99 (39.3%) reported race/ethnicity data. Recent trials were more likely to report these data (36% from 2007 to 2009; 51% 2013-2015; and 53% from 2016 to 2018, p = 0.01). Of all trials, ovarian cancer trials were least likely to report race/ethnicity data (32.1% vs 39.3%, p = 0.011). Population-adjusted under-enrollment for Blacks was 7-fold in ovarian cancer, Latinx 10-fold for ovarian and 6-fold in uterine cancer trials, Asians 2.5-fold in uterine cancer trials, and American Indian and Alaska Native individuals 6-fold in ovarian trials. Trials for most disease sites have enrolled more REMGs in recent years - REMGs made up 19.6% of trial participants in 2007-2009 compared to 38.1% in 2016-2018 (p < 0.0001). CONCLUSION: Less than half of trials that published results reported race/ethnicity data. Available data reveals that enrollment of REMGs is significantly below expected rates based on national census data. These disparities persisted even after additionally adjusting for population size. Despite improvement in recent years, additional recruitment of REMGs is needed to achieve more representative and equitable participation in gynecologic cancer clinical trials.


Asunto(s)
Neoplasias de los Genitales Femeninos , Neoplasias Ováricas , Neoplasias Uterinas , Humanos , Femenino , Estados Unidos , Neoplasias de los Genitales Femeninos/terapia , Etnicidad , Minorías Étnicas y Raciales , Grupos Minoritarios , Neoplasias Ováricas/terapia , Neoplasias Uterinas/terapia
5.
6.
Ecol Evol ; 13(9): e10540, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37720057

RESUMEN

The rapid pace of contemporary environmental change puts many species at risk, especially rare species constrained by limited capacity to adapt or migrate due to low genetic diversity and/or fitness. But the ability to acclimate can provide another way to persist through change. We compared the capacity of rare Boechera perstellata (Braun's rockcress) and widespread B. laevigata to acclimate to change. We investigated the phenotypic plasticity of growth, biomass allocation, and leaf morphology of individuals of B. perstellata and B. laevigata propagated from seed collected from several populations throughout their ranges in a growth chamber experiment to assess their capacity to acclimate. Concurrently, we assessed the genetic diversity of sampled populations using 17 microsatellite loci to assess evolutionary potential. Plasticity was limited in both rare B. perstellata and widespread B. laevigata, but differences in the plasticity of root traits between species suggest that B. perstellata may have less capacity to acclimate to change. In contrast to its widespread congener, B. perstellata exhibited no plasticity in response to temperature and weaker plastic responses to water availability. As expected, B. perstellata also had lower levels of observed heterozygosity than B. laevigata at the species level, but population-level trends in diversity measures were inconsistent due to high heterogeneity among B. laevigata populations. Overall, the ability of phenotypic plasticity to broadly explain the rarity of B. perstellata versus commonness of B. laevigata is limited. However, some contextual aspects of our plasticity findings compared with its relatively low genetic variability may shed light on the narrow range and habitat associations of B. perstellata and suggest its vulnerability to climate warming due to acclimatory and evolutionary constraints.

7.
Curr Opin Obstet Gynecol ; 35(2): 106-112, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36912334

RESUMEN

PURPOSE OF REVIEW: Twin gestations account for approximately 3% of all births. Although there appear to be physiologic differences in the third trimester growth of twins compared with singleton gestations, reasons for this remain unclear. As growth-restricted fetuses and neonates are at increased risk for adverse outcomes, there is a clinical need to optimize our ability to delineate normally from pathologically grown twins. RECENT FINDINGS: Recent studies have addressed current limitations in the way growth restriction is diagnosed in twin gestations. Twin-specific fetal and neonatal growth charts have been shown to decrease the number of cases inappropriately labeled as growth restricted compared with singleton nomograms. In addition, individual growth assessment (IGA) is a promising method of diagnosing pathological growth using each fetus's growth potential rather than a comparison of the estimated fetal weight with population nomograms. SUMMARY: There is a recent focus on improving our understanding of physiologic and pathologic twin growth. The increased use of twin-specific growth curves is likely to result in a decrease in the incidence of FGR diagnosis among twin gestations and could improve the outcomes of twins currently misclassified as FGR. Future research will hopefully clarify the reasons behind differences seen in twin versus singleton third trimester twin growth.


Asunto(s)
Retardo del Crecimiento Fetal , Gemelos , Embarazo , Recién Nacido , Femenino , Humanos , Retardo del Crecimiento Fetal/diagnóstico , Tercer Trimestre del Embarazo , Feto , Embarazo Gemelar , Estudios Retrospectivos
8.
J Perinatol ; 43(6): 702-708, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36973383

RESUMEN

OBJECTIVE: Identify clinical factors that delay or prolong spontaneous regression of retinopathy of prematurity (ROP). STUDY DESIGN: Secondary analysis of three prospective studies with 76 infants with ROP not requiring treatment, born ≤30 weeks postmenstrual age (PMA) and ≤1500 grams. Outcomes were PMA at greatest severity of ROP (PMA MSROP), at which regression began, at time of complete vascularization (PMA CV), and regression duration. Pearson's correlation coefficients, t-tests, or analyses of variance were calculated. RESULTS: Increased positive bacterial cultures, hyperglycemia, transfusion volume of platelets and red blood cells and severity of ROP were associated with later PMA MSROP. Positive bacterial cultures, maternal chorioamnionitis, and less iron deficiency were associated with later PMA CV and prolonged regression duration. Slower length gain was associated with later PMA CV. P < 0.05 for all. CONCLUSIONS: Preterm infants with inflammatory exposures or linear growth impairment may require longer surveillance for ROP resolution and complete vascularization.


Asunto(s)
Retinopatía de la Prematuridad , Lactante , Recién Nacido , Humanos , Retinopatía de la Prematuridad/terapia , Recien Nacido Prematuro , Estudios Prospectivos , Edad Gestacional , Factores de Riesgo , Estudios Retrospectivos
9.
J Med Imaging (Bellingham) ; 10(1): 016001, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36778671

RESUMEN

Purpose: The onset of atherosclerosis is preceded by changes in blood perfusion within the arterial wall due to localized proliferation of the vasa vasorum. The purpose of this study was to quantify these changes in spatial density of the vasa vasorum using a research whole-body photon-counting detector CT (PCD-CT) scanner and a porcine model. Approach: Vasa vasorum angiogenesis was stimulated in the left carotid artery wall of anesthetized pigs ( n = 5 ) while the right carotid served as a control. After a 6-week recovery period, the animals were scanned on the PCD-CT prior to and after injection of iodinated contrast. Annular regions of interest were used to measure wall enhancement in the injured and control arteries. The exact Wilcoxon-signed rank test was used to determine whether a significant difference in contrast enhancement existed between the injured and control arterial walls. Results: The greatest arterial wall enhancement was observed following contrast recirculation. The wall enhancement measurements made over these time points revealed that the enhancement was greater in the injured artery for 13/16 scanned arterial regions. Using an exact Wilcoxon-signed rank test, a significantly increased enhancement ratio was found in injured arteries compared with control arteries ( p = 0.013 ). Vasa vasorum angiogenesis was confirmed in micro-CT scans of excised arteries. Conclusions: Whole-body PCD-CT scanners can be used to detect and quantify the increased perfusion occurring within the porcine carotid arterial wall resulting from an increased density of vasa vasorum.

10.
JAMA Surg ; 158(2): 181-190, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36542396

RESUMEN

Importance: Clinical trials guide evidence-based obstetrics and gynecology (OB-GYN) but often enroll nonrepresentative participants. Objective: To characterize race and ethnicity reporting and representation in US OB-GYN clinical trials and their subsequent publications and to analyze the association of subspecialty and funding with diverse representation. Design and Setting: Cross-sectional analysis of all OB-GYN studies registered on ClinicalTrials.gov (2007-2020) and publications from PubMed and Google Scholar (2007-2021). Analyses included logistic regression controlling for year, subspecialty, phase, funding, and site number. Data from 332 417 studies were downloaded. Studies with a noninterventional design, with a registration date before October 1, 2007, without relevance to OB-GYN, with no reported results, and with no US-based study site were excluded. Exposures: OB-GYN subspecialty and funder. Main Outcomes and Measures: Reporting of race and ethnicity data and racial and ethnic representation (the proportion of enrollees of American Indian or Alaskan Native, Asian, Black, Latinx, or White identity and odds of representation above US Census estimates by race and ethnicity). Results: Among trials with ClinicalTrials.gov results (1287 trials with 591 196 participants) and publications (1147 trials with 821 111 participants), 662 (50.9%) and 856 (74.6%) reported race and ethnicity data, respectively. Among publications, gynecology studies were significantly less likely to report race and ethnicity than obstetrics (adjusted odds ratio [aOR], 0.54; 95% CI, 0.38-0.75). Reproductive endocrinology and infertility trials had the lowest odds of reporting race and ethnicity (aOR, 0.14; 95% CI, 0.07-0.27; reference category, obstetrics). Obstetrics and family planning demonstrated the most diverse clinical trial cohorts. Compared with obstetric trials, gynecologic oncology had the lowest odds of Black representation (ClinicalTrials.gov: aOR, 0.04; 95% CI, 0.02-0.09; publications: aOR, 0.06; 95% CI, 0.03-0.11) and Latinx representation (ClinicalTrials.gov: aOR, 0.05; 95% CI, 0.02-0.14; publications: aOR, 0.23; 95% CI, 0.10-0.48), followed by urogynecology and reproductive endocrinology and infertility. Urogynecology (ClinicalTrials.gov: aOR, 0.15; 95% CI, 0.05-0.39; publications: aOR, 0.24; 95% CI, 0.09-0.58) had the lowest odds of Asian representation. Conclusions and Relevance: Race and ethnicity reporting and representation in OB-GYN trials are suboptimal. Obstetrics and family planning trials demonstrate improved representation is achievable. Nonetheless, all subspecialties should strive for more equitably representative research.


Asunto(s)
Ginecología , Equidad en Salud , Infertilidad , Embarazo , Femenino , Humanos , Etnicidad , Estudios Transversales
11.
Clin Infect Dis ; 76(9): 1559-1566, 2023 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-36573005

RESUMEN

BACKGROUND: Long-term symptoms following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are a major concern, yet their prevalence is poorly understood. METHODS: We conducted a prospective cohort study comparing adults with SARS-CoV-2 infection (coronavirus disease-positive [COVID+]) with adults who tested negative (COVID-), enrolled within 28 days of a Food and Drug Administration (FDA)-approved SARS-CoV-2 test result for active symptoms. Sociodemographic characteristics, symptoms of SARS-CoV-2 infection (assessed with the Centers for Disease Control and Prevention [CDC] Person Under Investigation Symptom List), and symptoms of post-infectious syndromes (ie, fatigue, sleep quality, muscle/joint pains, unrefreshing sleep, and dizziness/fainting, assessed with CDC Short Symptom Screener for myalgic encephalomyelitis/chronic fatigue syndrome) were assessed at baseline and 3 months via electronic surveys sent via text or email. RESULTS: Among the first 1000 participants, 722 were COVID+ and 278 were COVID-. Mean age was 41.5 (SD 15.2); 66.3% were female, 13.4% were Black, and 15.3% were Hispanic. At baseline, SARS-CoV-2 symptoms were more common in the COVID+ group than the COVID- group. At 3 months, SARS-CoV-2 symptoms declined in both groups, although were more prevalent in the COVID+ group: upper respiratory symptoms/head/eyes/ears/nose/throat (HEENT; 37.3% vs 20.9%), constitutional (28.8% vs 19.4%), musculoskeletal (19.5% vs 14.7%), pulmonary (17.6% vs 12.2%), cardiovascular (10.0% vs 7.2%), and gastrointestinal (8.7% vs 8.3%); only 50.2% and 73.3% reported no symptoms at all. Symptoms of post-infectious syndromes were similarly prevalent among the COVID+ and COVID- groups at 3 months. CONCLUSIONS: Approximately half of COVID+ participants, as compared with one-quarter of COVID- participants, had at least 1 SARS-CoV-2 symptom at 3 months, highlighting the need for future work to distinguish long COVID. CLINICAL TRIALS REGISTRATION: NCT04610515.


Asunto(s)
COVID-19 , Envío de Mensajes de Texto , Adulto , Femenino , Humanos , Masculino , COVID-19/diagnóstico , COVID-19/epidemiología , Síndrome Post Agudo de COVID-19 , Estudios Prospectivos , SARS-CoV-2
12.
JAMA Netw Open ; 5(12): e2244486, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36454572

RESUMEN

Importance: Long-term sequelae after symptomatic SARS-CoV-2 infection may impact well-being, yet existing data primarily focus on discrete symptoms and/or health care use. Objective: To compare patient-reported outcomes of physical, mental, and social well-being among adults with symptomatic illness who received a positive vs negative test result for SARS-CoV-2 infection. Design, Setting, and Participants: This cohort study was a planned interim analysis of an ongoing multicenter prospective longitudinal registry study (the Innovative Support for Patients With SARS-CoV-2 Infections Registry [INSPIRE]). Participants were enrolled from December 11, 2020, to September 10, 2021, and comprised adults (aged ≥18 years) with acute symptoms suggestive of SARS-CoV-2 infection at the time of receipt of a SARS-CoV-2 test approved by the US Food and Drug Administration. The analysis included the first 1000 participants who completed baseline and 3-month follow-up surveys consisting of questions from the 29-item Patient-Reported Outcomes Measurement Information System (PROMIS-29; 7 subscales, including physical function, anxiety, depression, fatigue, social participation, sleep disturbance, and pain interference) and the PROMIS Short Form-Cognitive Function 8a scale, for which population-normed T scores were reported. Exposures: SARS-CoV-2 status (positive or negative test result) at enrollment. Main Outcomes and Measures: Mean PROMIS scores for participants with positive COVID-19 tests vs negative COVID-19 tests were compared descriptively and using multivariable regression analysis. Results: Among 1000 participants, 722 (72.2%) received a positive COVID-19 result and 278 (27.8%) received a negative result; 406 of 998 participants (40.7%) were aged 18 to 34 years, 644 of 972 (66.3%) were female, 833 of 984 (84.7%) were non-Hispanic, and 685 of 974 (70.3%) were White. A total of 282 of 712 participants (39.6%) in the COVID-19-positive group and 147 of 275 participants (53.5%) in the COVID-19-negative group reported persistently poor physical, mental, or social well-being at 3-month follow-up. After adjustment, improvements in well-being were statistically and clinically greater for participants in the COVID-19-positive group vs the COVID-19-negative group only for social participation (ß = 3.32; 95% CI, 1.84-4.80; P < .001); changes in other well-being domains were not clinically different between groups. Improvements in well-being in the COVID-19-positive group were concentrated among participants aged 18 to 34 years (eg, social participation: ß = 3.90; 95% CI, 1.75-6.05; P < .001) and those who presented for COVID-19 testing in an ambulatory setting (eg, social participation: ß = 4.16; 95% CI, 2.12-6.20; P < .001). Conclusions and Relevance: In this study, participants in both the COVID-19-positive and COVID-19-negative groups reported persistently poor physical, mental, or social well-being at 3-month follow-up. Although some individuals had clinically meaningful improvements over time, many reported moderate to severe impairments in well-being 3 months later. These results highlight the importance of including a control group of participants with negative COVID-19 results for comparison when examining the sequelae of COVID-19.


Asunto(s)
COVID-19 , SARS-CoV-2 , Estados Unidos/epidemiología , Adulto , Humanos , Femenino , Adolescente , Masculino , Prueba de COVID-19 , COVID-19/diagnóstico , Estudios de Cohortes , Estudios Prospectivos , Progresión de la Enfermedad
13.
Am J Bot ; 109(11): 1939-1961, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36371714

RESUMEN

Model systems in biology expand the research capacity of individuals and the community. Closely related to Arabidopsis, the genus Boechera has emerged as an important ecological model owing to the ability to integrate across molecular, functional, and eco-evolutionary approaches. Boechera species are broadly distributed in relatively undisturbed habitats predominantly in western North America and provide one of the few experimental systems for identification of ecologically important genes through genome-wide association studies and investigations of selection with plants in their native habitats. The ecologically, evolutionarily, and agriculturally important trait of apomixis (asexual reproduction via seeds) is common in the genus, and field experiments suggest that abiotic and biotic environments shape the evolution of sex. To date, population genetic studies have focused on the widespread species B. stricta, detailing population divergence and demographic history. Molecular and ecological studies show that balancing selection maintains genetic variation in ~10% of the genome, and ecological trade-offs contribute to complex trait variation for herbivore resistance, flowering phenology, and drought tolerance. Microbiome analyses have shown that host genotypes influence leaf and root microbiome composition, and the soil microbiome influences flowering phenology and natural selection. Furthermore, Boechera offers numerous opportunities for investigating biological responses to global change. In B. stricta, climate change has induced a shift of >2 weeks in the timing of first flowering since the 1970s, altered patterns of natural selection, generated maladaptation in previously locally-adapted populations, and disrupted life history trade-offs. Here we review resources and results for this eco-evolutionary model system and discuss future research directions.


Asunto(s)
Apomixis , Arabidopsis , Brassicaceae , Estudio de Asociación del Genoma Completo , Brassicaceae/fisiología , Selección Genética , Fenotipo , Arabidopsis/genética
14.
Am J Bot ; 109(11): 1702-1716, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36031862

RESUMEN

PREMISE: Global change has changed resource availability to plants, which could shift the adaptive landscape. We hypothesize that novel water and nutrient availability combinations alter patterns of natural selection on reproductive phenology in Boechera stricta (Brassicaceae) and influence the evolution of local adaptation. METHODS: We conducted a multifactorial greenhouse study using 35 accessions of B. stricta sourced from a broad elevational gradient in the Rocky Mountains. We exposed full siblings to three soil water and two nutrient availability treatment levels, reflecting current and projected future conditions. In addition, we quantified fitness (seed count) and four phenological traits: the timing of first flowering, the duration of flowering, and height and leaf number at flowering. RESULTS: Selection favored early flowering and longer duration of flowering, and the genetic correlation between these traits accorded with the direction of selection. In most treatments, we found selection for increased height, but selection on leaf number depended on water availability, with selection favoring more leaves in well-watered conditions and fewer leaves under severe drought. Low-elevation genotypes had the greatest fitness under drought stress, consistent with local adaptation. CONCLUSIONS: We found evidence of strong selection on these heritable traits. Furthermore, the direction and strength of selection on size at flowering depended on the variable measured (height vs. leaf number). Finally, selection often favored both early flowering and a longer duration of flowering. Selection on these two components of phenology can be difficult to disentangle due to tight genetic correlations.


Asunto(s)
Brassicaceae , Agua , Selección Genética , Brassicaceae/genética , Reproducción , Nutrientes , Flores/genética
15.
Am J Obstet Gynecol MFM ; 4(6): 100696, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35872356

RESUMEN

BACKGROUND: Obstetrical clinical trials are the foundation of evidence-based medicine during pregnancy. As more obstetrical trials are conducted, understanding the publication characteristics of these trials is of utmost importance to advance obstetrical health. OBJECTIVE: This study aimed to characterize the frequency of publication and trial characteristics associated with publication among obstetrical clinical trials in the United States. We additionally sought to examine time from trial completion to publication. STUDY DESIGN: This was a cross-sectional analysis of completed obstetrical trials with an intervention design and at least 1 site in the United States registered to ClinicalTrials.gov from 2007 to 2019. Trial characteristics were cross-referenced with PubMed to determine publication status up to 2021 using the National Clinical Trial identification number. Bivariable analyses were conducted to determine trial characteristics associated with publication. Multivariable logistic regression models controlling for prespecified covariates were generated to estimate the relationship between funding, primary purpose, and therapeutic foci with publication. Additional exploratory analyses of other trial characteristics were conducted. Time to publication was analyzed using Kaplan-Meier curves and Cox regression models. RESULTS: Of the 1879 obstetrical trials with registered completion, a total of 575 (30.6%) had at least 1 site in the United States, were completed before October 1, 2019, and were included in this analysis. Between October 2007 and October 2019, fewer than two-thirds (N=348, 60.5%) of trials reached publication. Annual rates of publication ranged from 46.4% in 2018 to 70.0% in 2007. No difference was observed in publication by funding, primary purpose, or therapeutic foci (all P>.05). Trials with characteristics indicating high trial quality-including randomized allocation scheme, ≥50 participants enrolled, ≥2 sites, and presence of a data safety monitoring committee-had increased odds of publication compared with those without such characteristics (all P<.05). For example, studies with randomized allocation of intervention had 2-fold greater odds of publication than nonrandomized studies (adjusted odds ratio, 2.09; 95% confidence interval, 1.30-3.37). Studies with ≥150 participants had nearly 8-fold odds of publication (adjusted odds ratio, 7.90; 95% confidence interval, 3.78-17.49) relative to studies with <50 participants. Temporal analysis demonstrated variability in time to publication among obstetrical trials, with a median time of 20.1 months after trial completion, and with most trials that reached publication having been published by 40 months. No difference was observed in time to publication by funding, primary purpose, or therapeutic foci (all P>.05). CONCLUSION: Publication of obstetrical trials remains suboptimal, with significant differences observed between trials with indicators of high quality and those without. Most trials that reach publication are published within 2 years of registered completion on ClinicalTrials.gov.

16.
Mol Ecol ; 31(14): 3739-3741, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35598168

RESUMEN

Local adaptation has evolved in numerous taxa across the tree of life in response to divergent selection acting on populations that inhabit different environments (Briscoe Runquist et al., 2019; Hargreaves et al., 2019; Hereford, 2009). The genetic basis of local adaptation has intrigued researchers for decades. In their foundational reciprocal transplant study, Clausen and Hiesey (1960) evaluated the genetics of adaptation primarily using hybrid lines derived from crosses of low elevation and alpine Potentilla glandulosa (Rosaceae) ecotypes. Their work revealed that transgressive segregation can lead to a wider range of trait values than expressed by the parents, complex traits are often genetically correlated and evolve in tandem, and local adaptation is typically polygenic, that is, controlled by many loci of small effect (Clausen & Hiesey, 1960). Within the past 15 years, a burgeoning literature has investigated whether local adaptation evolves through genetic trade-offs, such that local alleles at a QTL (quantitative trait locus) or candidate gene have a fitness advantage in their home environment, but suffer a fitness cost when transplanted into a contrasting habitat type (Mitchell-Olds et al., 2007). Alternatively, local adaptation could arise through conditional neutrality, in which an allele native to one habitat type has elevated fitness in its home site relative to foreign alleles, but is not at a fitness disadvantage elsewhere. Conditional neutrality could maintain local adaptation if gene flow is spatially restricted (Hall et al., 2010). In a From the Cover article in this issue of Molecular Ecology, Wright et al. (2022) examined the genetic basis of local adaptation in white clover (Trifolium repens), discovering strong signatures of local adaptation, and revealing that both genetic trade-offs and conditional neutrality contribute to local adaptation. The most surprising and intriguing result to emerge from this study was that variation in a key antiherbivore defence did not appear to influence contemporary patterns of local adaptation. Rather, divergence in life history strategies was crucial, with early reproduction favoured in the southern garden and delayed reproduction and longer lifespans emerging in the north. These findings highlight the challenges of identifying the multivariate targets of divergent selection in locally-adapted systems, and reveal that not all traits that vary across populations contribute to adaptive differentiation. As studies continue to investigate local adaptation, experiments that manipulate environmental conditions and quantify the magnitude and direction of selection on traits will shed light on the processes that drive local adaptation.


Asunto(s)
Rasgos de la Historia de Vida , Trifolium , Adaptación Fisiológica/genética , Sitios de Carácter Cuantitativo/genética , Selección Genética , Trifolium/genética
17.
Obstet Gynecol ; 139(5): 821-831, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35576341

RESUMEN

OBJECTIVE: To characterize gynecology clinical trials over time, compare gynecology subspecialties, and analyze factors associated with early discontinuation, results reporting, and publication. METHODS: We conducted a cross-sectional analysis of all gynecology trials registered on ClinicalTrials.gov between 2007 and 2020 and their resulting publications. Trials were analyzed with descriptive, multivariable logistic, and Cox regression analyses. Primary exposure variables were trial funding and subspecialty. The three primary outcomes included early discontinuation, results reporting to ClinicalTrials.gov, and publication in a peer-reviewed journal indexed on PubMed. RESULTS: Of 223,690 trials registered on ClinicalTrials.gov between October 2007 and March 2020, only 3.7% focused on gynecology (n=8,174, approximately 3,759,086 participants). Subspecialties included reproductive endocrinology and infertility (n=1,428, 17.5%), gynecologic oncology (n=2,063, 25.2%), urogynecology (n=1,118, 13.7%), family planning (n=648, 7.9%), and other benign gynecology (n=2,917, 35.7%). Only 42.0% of completed trials disseminated results through results reporting and publication. Of all funding types, industry-funded trials were the most likely to be discontinued early (P<.001). Academic-funded trials were the least likely to report results (adjusted odds ratio [aOR] 0.38, 95% CI 0.30-0.50) but the most likely to publish (aOR 1.62, 95% CI 1.24-2.12). The number of reproductive endocrinology and infertility trials increased the most of any subspecialty between 2007 and 2020 (6.4% growth rate). Reproductive endocrinology and infertility and family planning trials were the most likely to be stopped early (reproductive endocrinology and infertility: adjusted hazard ratio [aHR] 2.08, 95% CI 1.59-2.71; family planning: aHR 1.55 95% CI 1.06-2.25). When completed, reproductive endocrinology and infertility trials were the least likely to report results (aOR 0.58, 95% CI 0.38-0.88). No significant differences were seen between subspecialties with respect to publication. CONCLUSION: Gynecology trials comprise only 3.7% of all clinical trials. The paucity of gynecology clinical trials aligns with decades of female underrepresentation in research. When completed, gynecology trials have poor dissemination. Our findings raise concern about bias in the performance, reporting, and publication of gynecology clinical trials.


Asunto(s)
Ginecología , Infertilidad , Estudios Transversales , Femenino , Humanos , Oportunidad Relativa , Informe de Investigación
18.
New Phytol ; 235(3): 1272-1286, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35460282

RESUMEN

Species differ dramatically in their prevalence in the natural world, with many species characterized as rare due to restricted geographic distribution, low local abundance and/or habitat specialization. We investigated the ecoevolutionary causes and consequences of rarity with phylogenetically controlled metaanalyses of population genetic diversity, fitness and functional traits in rare and common congeneric plant species. Our syntheses included 252 rare species and 267 common congeners reported in 153 peer-reviewed articles published from 1978 to 2020 and one manuscript in press. Rare species have reduced population genetic diversity, depressed fitness and smaller reproductive structures than common congeners. Rare species also could suffer from inbreeding depression and reduced fertilization efficiency. By limiting their capacity to adapt and migrate, these characteristics could influence contemporary patterns of rarity and increase the susceptibility of rare species to rapid environmental change. We recommend that future studies present more nuanced data on the extent of rarity in focal species, expose rare and common species to ecologically relevant treatments, including reciprocal transplants, and conduct quantitative genetic and population genomic analyses across a greater array of systems. This research could elucidate the processes that contribute to rarity and generate robust predictions of extinction risks under global change.


Asunto(s)
Ecosistema , Plantas , Evolución Biológica , Plantas/genética , Reproducción
19.
Front Immunol ; 13: 841910, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35309313

RESUMEN

Myalgic encephalomyelitis, or chronic fatigue syndrome (ME/CFS) is a serious disease whose cause has yet to be identified. Objective markers of the disease are also not well understood and would serve as important tools in diagnosis and management. One potential biomarker or transmitter of immune signals in ME/CFS is the extracellular vesicle (EV) compartment. These small, membrane bound particles have been shown to play a key role in intercellular signaling. Our laboratory has focused on methods of detection of EVS in clinical samples. In this study we explored whether the prevalence of EVs in the plasma of participants with mild or severe ME/CFS differed from the plasma of healthy control participants. By staining for multiple cell surface molecules, plasma EVs could be fingerprinted as to their cell of origin. Our study revealed a significant correlation between severe ME/CSF and levels of EVs bearing the B cell marker CD19 and the platelet marker CD41a, though these changes were not significant after correction for multiple comparisons. These findings point to potential dysregulation of B cell and platelet activation or homeostasis in ME/CFS, which warrants validation in a replication cohort and further exploration of potential mechanisms underlying the association.


Asunto(s)
Vesículas Extracelulares , Síndrome de Fatiga Crónica , Linfocitos B/metabolismo , Biomarcadores , Estudios de Cohortes , Vesículas Extracelulares/metabolismo , Síndrome de Fatiga Crónica/diagnóstico , Humanos
20.
Science ; 375(6586): 1275-1281, 2022 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-35298255

RESUMEN

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale.


Asunto(s)
Adaptación Fisiológica , Evolución Biológica , Ecosistema , Trifolium/fisiología , Urbanización , Ciudades , Genes de Plantas , Genoma de Planta , Cianuro de Hidrógeno/metabolismo , Población Rural , Trifolium/genética
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