27 research outputs found
Reproductive success through high pollinator visitation rates despite self incompatibility in an endangered wallflower
PREMISE OF THE STUDY: Self incompatibility (SI) in rare plants presents a unique challenge—SI protects plants from inbreeding depression, but requires a sufficient number of mates and xenogamous pollination. Does SI persist in an endangered polyploid? Is pollinator visitation sufficient to ensure reproductive success? Is there evidence of inbreeding/outbreeding depression? We characterized the mating system, primary pollinators, pollen limitation, and inbreeding/outbreeding depression in Erysimum teretifolium to guide conservation efforts. METHODS: We compared seed production following self pollination and within- and between-population crosses. Pollen tubes were visualized after self pollinations and between-population pollinations. Pollen limitation was tested in the field. Pollinator observations were quantified using digital video. Inbreeding/outbreeding depression was assessed in progeny from self and outcross pollinations at early and later developmental stages. KEY RESULTS: Self-pollination reduced seed set by 6.5× and quadrupled reproductive failure compared with outcross pollination. Pollen tubes of some self pollinations were arrested at the stigmatic surface. Seed-set data indicated strong SI, and fruit-set data suggested partial SI. Pollinator diversity and visitation rates were high, and there was no evidence of pollen limitation. Inbreeding depression (δ) was weak for early developmental stages and strong for later developmental stages, with no evidence of outbreeding depression. CONCLUSIONS: The rare hexaploid E. teretifolium is largely self incompatible and suffers from late-acting inbreeding depression. Reproductive success in natural populations was accomplished through high pollinator visitation rates consistent with a lack of pollen limitation. Future reproductive health for this species will require large population sizes with sufficient mates and a robust pollinator community
Association of sexual relationship power with PrEP persistence and other sexual health outcomes among adolescent and young women in Kenya and South Africa
IntroductionGendered power inequalities impact adolescent girls’ and young women's (AGYW) sexual and reproductive health (SRH) outcomes. We investigated the influence of sexual relationship power on AGYW's SRH outcomes, including HIV pre-exposure prophylaxis (PrEP) persistence.MethodsThe POWER study in Kisumu, Kenya, and Cape Town and Johannesburg, South Africa provided PrEP to 2,550 AGYW (aged 16–25). AGYW's perceived power in their primary sexual relationship was measured among the first 596 participants enrolled using the Sexual Relationship Power Scale's (SRPS) relationship control sub-scale. Multivariable regression was used to test for (1) key sociodemographic and relationship characteristics associated with relationship power; and (2) the association of relationship power with SRH outcomes including PrEP persistence.ResultsIn this cohort, the mean SRPS score was 2.56 (0.49), 542 (90.9%) initiated PrEP; 192 (35.4%) persisted with PrEP at 1 month of which 46 (24.0% of 192) persisted at 6 months. SRPS were significantly lower among AGYW who cohabited with their sex partner (−0.14, 95% CI: −0.24 to −0.04, p = 0.01), or had ≥1 sex partner (−0.10, 95% CI: −0.19 to −0.00, p = 0.05). AGYW with lower SRPS were more likely to not know their partner's HIV status (aOR 2.05, 95% CI: 1.27 to 3.33, p < 0.01), but SRPS was not associated with PrEP persistence, STI infection, condom, or hormonal contraception use.DiscussionAGYW's reasons for initiating PrEP and reasons for continuously using PrEP may be different. While low relationship power was associated with perceived HIV vulnerability, AGYW's PrEP persistence may be influenced by more than relationship power
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Effect of Hydrocortisone on Mortality and Organ Support in Patients With Severe COVID-19: The REMAP-CAP COVID-19 Corticosteroid Domain Randomized Clinical Trial.
Importance: Evidence regarding corticosteroid use for severe coronavirus disease 2019 (COVID-19) is limited. Objective: To determine whether hydrocortisone improves outcome for patients with severe COVID-19. Design, Setting, and Participants: An ongoing adaptive platform trial testing multiple interventions within multiple therapeutic domains, for example, antiviral agents, corticosteroids, or immunoglobulin. Between March 9 and June 17, 2020, 614 adult patients with suspected or confirmed COVID-19 were enrolled and randomized within at least 1 domain following admission to an intensive care unit (ICU) for respiratory or cardiovascular organ support at 121 sites in 8 countries. Of these, 403 were randomized to open-label interventions within the corticosteroid domain. The domain was halted after results from another trial were released. Follow-up ended August 12, 2020. Interventions: The corticosteroid domain randomized participants to a fixed 7-day course of intravenous hydrocortisone (50 mg or 100 mg every 6 hours) (n = 143), a shock-dependent course (50 mg every 6 hours when shock was clinically evident) (n = 152), or no hydrocortisone (n = 108). Main Outcomes and Measures: The primary end point was organ support-free days (days alive and free of ICU-based respiratory or cardiovascular support) within 21 days, where patients who died were assigned -1 day. The primary analysis was a bayesian cumulative logistic model that included all patients enrolled with severe COVID-19, adjusting for age, sex, site, region, time, assignment to interventions within other domains, and domain and intervention eligibility. Superiority was defined as the posterior probability of an odds ratio greater than 1 (threshold for trial conclusion of superiority >99%). Results: After excluding 19 participants who withdrew consent, there were 384 patients (mean age, 60 years; 29% female) randomized to the fixed-dose (n = 137), shock-dependent (n = 146), and no (n = 101) hydrocortisone groups; 379 (99%) completed the study and were included in the analysis. The mean age for the 3 groups ranged between 59.5 and 60.4 years; most patients were male (range, 70.6%-71.5%); mean body mass index ranged between 29.7 and 30.9; and patients receiving mechanical ventilation ranged between 50.0% and 63.5%. For the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively, the median organ support-free days were 0 (IQR, -1 to 15), 0 (IQR, -1 to 13), and 0 (-1 to 11) days (composed of 30%, 26%, and 33% mortality rates and 11.5, 9.5, and 6 median organ support-free days among survivors). The median adjusted odds ratio and bayesian probability of superiority were 1.43 (95% credible interval, 0.91-2.27) and 93% for fixed-dose hydrocortisone, respectively, and were 1.22 (95% credible interval, 0.76-1.94) and 80% for shock-dependent hydrocortisone compared with no hydrocortisone. Serious adverse events were reported in 4 (3%), 5 (3%), and 1 (1%) patients in the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively. Conclusions and Relevance: Among patients with severe COVID-19, treatment with a 7-day fixed-dose course of hydrocortisone or shock-dependent dosing of hydrocortisone, compared with no hydrocortisone, resulted in 93% and 80% probabilities of superiority with regard to the odds of improvement in organ support-free days within 21 days. However, the trial was stopped early and no treatment strategy met prespecified criteria for statistical superiority, precluding definitive conclusions. Trial Registration: ClinicalTrials.gov Identifier: NCT02735707
A picky palate? The host plant selection of an endangered June beetle
Precise information about endangered species, in particular identifying their resources requirements, is needed to identify areas that might support populations. Little is known about the endangered Mount Hermon June Beetle (Polyphylla barbata) found only within Zayante soils region of Santa Cruz County, California. We investigated the beetle’s host plant selection, habitat association and mating behavior between June 2004 and September 2005. We identified angiosperm and Pteridophyta phyla, and fungi within the frass pellets of Mount Hermon June Beetle larvae demonstrating that they are not specialist feeders but are microhabitat specialists. Larval species was confirmed by DNA analysis. Significant differences were found in vegetation assemblages between regions where the Mount Hermon June Beetle did and did not occur for Chorizanthe pungens var. hartwegiana, and bare ground
Electronic health record tools to assist with children’s insurance coverage: a mixed methods study
Abstract Background Children with health insurance have increased access to healthcare and receive higher quality care. However, despite recent initiatives expanding children’s coverage, many remain uninsured. New technologies present opportunities for helping clinics provide enrollment support for patients. We developed and tested electronic health record (EHR)-based tools to help clinics provide children’s insurance assistance. Methods We used mixed methods to understand tool adoption, and to assess impact of tool use on insurance coverage, healthcare utilization, and receipt of recommended care. We conducted intent-to-treat (ITT) analyses comparing pediatric patients in 4 intervention clinics (n = 15,024) to those at 4 matched control clinics (n = 12,227). We conducted effect-of-treatment-on-the-treated (ETOT) analyses comparing intervention clinic patients with tool use (n = 2240) to intervention clinic patients without tool use (n = 12,784). Results Tools were used for only 15% of eligible patients. Qualitative data indicated that tool adoption was limited by: (1) concurrent initiatives that duplicated the work associated with the tools, and (2) inability to obtain accurate insurance coverage data and end dates. The ITT analyses showed that intervention clinic patients had higher odds of gaining insurance coverage (adjusted odds ratio [aOR] = 1.32, 95% confidence interval [95%CI] 1.14–1.51) and lower odds of losing coverage (aOR = 0.77, 95%CI 0.68–0.88), compared to control clinic patients. Similarly, ETOT findings showed that intervention clinic patients with tool use had higher odds of gaining insurance (aOR = 1.83, 95%CI 1.64–2.04) and lower odds of losing coverage (aOR = 0.70, 95%CI 0.53–0.91), compared to patients without tool use. The ETOT analyses also showed higher rates of receipt of return visits, well-child visits, and several immunizations among patients for whom the tools were used. Conclusions This pragmatic trial, the first to evaluate EHR-based insurance assistance tools, suggests that it is feasible to create and implement tools that help clinics provide insurance enrollment support to pediatric patients. While ITT findings were limited by low rates of tool use, ITT and ETOT findings suggest tool use was associated with better odds of gaining and keeping coverage. Further, ETOT findings suggest that use of such tools may positively impact healthcare utilization and quality of pediatric care. Trial registration ClinicalTrials.gov, NCT02298361; retrospectively registered on November 5, 2014
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