Management Strategies for Acute Pulmonary Embolism in the Intensive Care Unit.

TOPIC IMPORTANCE: Acute pulmonary embolism (PE) is a common disease encountered by pulmonologists, cardiologists, and critical care physicians throughout the world. For patients with high risk (defined by systemic hypotension) and intermediate high-risk (defined by the absence of systemic hypotension but the presence of numerous other concerning clinical and imaging features) acute PE, intensive care is often necessary. Initial management strategies should focus on optimization of right ventricular (RV) function while decisions about advanced interventions are being considered. REVIEW FINDINGS: Here we review the existing literature of various vasoactive agents, intravenous fluids and diuretics, and pulmonary vasodilators in both animal models and human trials of acute PE. We also review the potential complications of endotracheal intubation and positive pressure ventilation in acute PE. Finally, we review the data of veno-arterial extracorporeal membrane oxygen use in acute PE. The above interventions are discussed in the context of the underlying pathophysiology of acute RV failure in acute PE with corresponding illustrations. SUMMARY: Norepinephrine is a reasonable first choice for hemodynamic support with vasopressin as an adjunct. Intravenous loop diuretics may be useful if there is evidence of RV dysfunction or volume overload. Fluids should only be given if there is concern for hypovolemia and absence of RV dilatation. Supplemental oxygen administration should be considered even without hypoxemia. Positive pressure ventilation should be avoided if possible. VA-ECMO cannulation should be implemented early if ongoing deterioration occurs despite these interventions.

Effects of SPEAK OUT! & LOUD Crowd on Functional Speech Measures in Parkinson's Disease.

PURPOSE: This study investigated the effects of the SPEAK OUT! & LOUD Crowd therapy program on speaking rate, percent pause time, intelligibility, naturalness, and communicative participation in individuals with Parkinson's disease (PD). METHOD: Six adults with PD completed 12 individual SPEAK OUT! sessions across four consecutive weeks followed by group-based LOUD Crowd sessions for five consecutive weeks. Most therapy sessions were conducted via telehealth, with two participants completing the SPEAK OUT! portion in person. Speech samples were recorded at six time points: three baseline time points prior to SPEAK OUT!, two post-SPEAK OUT! time points, and one post-LOUD Crowd time point. Acoustic measures of speaking rate and percent pause time and listener ratings of speech intelligibility and naturalness were obtained for each time point. Participant self-ratings of communicative participation were also collected at pre- and posttreatment time points. RESULTS: Results showed significant improvement in communicative participation scores at a group level following completion of the SPEAK OUT! & LOUD Crowd treatment program. Two participants showed a significant decrease in speaking rate and increase in percent pause time following treatment. Changes in intelligibility and naturalness were not statistically significant. CONCLUSIONS: These findings provide preliminary support for the effectiveness of the SPEAK OUT! & LOUD Crowd treatment program in improving communicative participation for people with mild-to-moderate hypokinetic dysarthria secondary to PD. This study is also the first to demonstrate positive effects of this treatment program for people receiving the therapy via telehealth.

Climate and habitat type interact to influence contemporary dispersal potential in Prairie Smoke (Geum triflorum).

Understanding dispersal potential, or the probability a species will move a given distance, under different environmental conditions is essential to predicting species' ability to move across the landscape and track shifting ecological niches. Two important drivers of dispersal ability are climatic differences and variations in local habitat type. Despite the likelihood these global drivers act simultaneously on plant populations, and thus dispersal potential is likely to change as a result, their combined effects on dispersal are rarely examined. To understand the effect of climate and varying habitat types on dispersal potential, we studied Geum triflorum-a perennial grassland species that spans a wide range of environments, including both prairie and alvar habitats. We explored how the climate of the growing season and habitat type (prairie vs. alvar) interact to alter dispersal potential. We found a consistent interactive effect of climate and habitat type on dispersal potential. Across prairie populations, an increased number of growing degree days favored traits that increase dispersal potential or the probability of dispersing farther distances. However, for alvar populations, dispersal potential tended to decrease as the number of growing degree days increased. Our findings suggest that under continued warming, populations in prairie habitats will benefit from increased gene flow, while alvar populations will become increasingly segregated, with reduced potential to track shifting fitness optima.

Early-Onset Hearing Loss in Mouse Models of Alzheimer's Disease and Increased DNA Damage in the Cochlea.

There is considerable interest in whether sensory deficiency is associated with the development of Alzheimer's disease (AD). Notably, the relationship between hearing impairment and AD is of high relevance but still poorly understood. In this study, we found early-onset hearing loss in two AD mouse models, 3xTgAD and 3xTgAD/Polß+/-. The 3xTgAD/Polß+/- mouse is DNA repair deficient and has more humanized AD features than the 3xTgAD. Both AD mouse models showed increased auditory brainstem response (ABR) thresholds between 16 and 32 kHz at 4 weeks of age, much earlier than any AD cognitive and behavioral changes. The ABR thresholds were significantly higher in 3xTgAD/Polß+/- mice than in 3xTgAD mice at 16 kHz, and distortion product otoacoustic emission signals were reduced, indicating that DNA damage may be a factor underlying early hearing impairment in AD. Poly ADP-ribosylation and protein expression levels of DNA damage markers increased significantly in the cochlea of the AD mice but not in the adjacent auditory cortex. Phosphoglycerate mutase 2 levels and the number of synaptic ribbons in the presynaptic zones of inner hair cells were decreased in the cochlea of the AD mice. Furthermore, the activity of sirtuin 3 was downregulated in the cochlea of these mice, indicative of impaired mitochondrial function. Taken together, these findings provide new insights into potential mechanisms for hearing dysfunction in AD and suggest that DNA damage in the cochlea might contribute to the development of early hearing loss in AD.

Family Caregiver Experiences in the Inpatient and Outpatient Reduced-Intensity Conditioning Allogeneic Hematopoietic Cell Transplantation Settings: A Qualitative Study.

Caregivers (ie, family and friends) are essential in providing care and support for patients undergoing hematopoietic cell transplantation (HCT) and throughout their recovery. Traditionally delivered in the hospital, HCT is being increasingly provided in the outpatient setting, potentially heightening the burden on caregivers. Extensive work has examined the inpatient HCT caregiving experience, yet little is known about how caregiver experiences may differ based on whether the HCT was delivered on an inpatient or outpatient basis, particularly during the acute recovery period post-HCT. This study explored the similarities and differences in caregiver experiences in the inpatient and outpatient settings during the early recovery from reduced-intensity conditioning (RIC) allogeneic HCT. We conducted semistructured interviews (n = 15) with caregivers of adults undergoing RIC allogeneic HCT as either an inpatient (n = 7) or an outpatient (n = 8). We recruited caregivers using purposeful criterion sampling, based on the HCT setting, until thematic saturation occurred. Interview recordings were transcribed and coded through thematic analysis using Dedoose v.9.0. The study analysis was guided by the transactional model of stress and coping and the model of adaptation of family caregivers during the acute phase of BMT. Three themes emerged to describe similar experiences for HCT caregivers regardless of setting: (1) caregivers reported feeling like they were a necessary yet invisible part of the care team; (2) caregivers described learning to adapt to changing situations and varying patient needs; and (3) caregivers recounted how the uncertainty following HCT felt like existing between life and death while also maintaining a sense of gratitude and hope for the future. Caregivers also reported distinct experiences based on the transplantation setting and 4 themes emerged: (1) disrupted routines: inpatient caregivers reported disrupted routines when caring for the HCT recipient while simultaneously trying to manage non-caregiving responsibilities at home and work, and outpatient caregivers reported having to establish new routines that included frequent clinic visits with the patient while altering or pausing home and work responsibilities; (2) timing of caregiver involvement: inpatient caregivers felt more involved in care after the patient was discharged from the HCT hospitalization, whereas outpatient caregivers were already providing the majority of care earlier in the post-transplantation period; (3) fear of missing vital information: inpatient caregivers worried about missing vital information about the patient's care and progress if not physically present in the hospital, whereas outpatient caregivers feared overlooking vital information that may warrant contacting the care team as they monitored the patient at home; and (4) perceived adequacy of resources to meet psychosocial and practical needs: inpatient caregivers reported having adequate access to resources (ie, hospital-based services), whereas outpatient caregivers felt they had more limited access and needed to be resourceful in seeking out assistance. Inpatient and outpatient HCT caregivers described both similar and distinct experiences during the acute recovery period post-HCT. Specific interventions should address caregiver psychosocial needs (ie, distress, illness uncertainty, communication, and coping) and practical needs (ie, community resource referral, preparedness for home-based caregiving, and transplantation education) of HCT caregivers based on setting.

A qualitative study of LGBTQIA+ genetic counselors' experiences while applying to graduate school.

Research has shown that lesbian, gay, bisexual, transgender, queer, intersex, asexual and other sexual and gender minority (LGBTQIA+) healthcare students experience discrimination during admissions and training. While several studies have examined the experiences of racial and ethnic minorities within the genetic counseling field, the admissions experiences of LGBTQIA+ individuals have not been explored. Through semi-structured interviews, this qualitative study investigated the experiences of ten LGBTQIA+ genetic counselors and genetic counseling students during graduate school admissions. Interview questions focused on participants' perceptions of the genetic counseling field prior to applying, important factors in choosing and ranking programs, decisions surrounding disclosure of LGBTQIA+ identities, interview experiences related to their identities, and the impacts, if any, of their identities on their overall admissions journey. Transcripts were coded and analyzed utilizing a constructivist grounded theory approach, resulting in the emergence of themes regarding factors that influenced participants' decisions to disclose their identity and how their LGBTQIA+ identity factored into their selection of a training program. This study adds new perspectives to the conversations around diversity, equity, and inclusion within the genetic counseling field. Further, it provides genetic counselors and genetic counseling programs insight into inclusive admissions processes and suggests ways to improve inclusivity in graduate admissions.

Herbivory and nutrients shape grassland soil seed banks.

Anthropogenic nutrient enrichment and shifts in herbivory can lead to dramatic changes in the composition and diversity of aboveground plant communities. In turn, this can alter seed banks in the soil, which are cryptic reservoirs of plant diversity. Here, we use data from seven Nutrient Network grassland sites on four continents, encompassing a range of climatic and environmental conditions, to test the joint effects of fertilization and aboveground mammalian herbivory on seed banks and on the similarity between aboveground plant communities and seed banks. We find that fertilization decreases plant species richness and diversity in seed banks, and homogenizes composition between aboveground and seed bank communities. Fertilization increases seed bank abundance especially in the presence of herbivores, while this effect is smaller in the absence of herbivores. Our findings highlight that nutrient enrichment can weaken a diversity maintaining mechanism in grasslands, and that herbivory needs to be considered when assessing nutrient enrichment effects on seed bank abundance.

Take me for a ride: Herbivores can facilitate plant reinvasions.

Herbivores shape plant invasions through impacts on demography and dispersal, yet only demographic mechanisms are well understood. Although herbivores negatively impact demography by definition, they can affect dispersal either negatively (e.g., seed consumption), or positively (e.g., caching). Exploring the nuances of how herbivores influence spatial spread will improve the forecasting of plant movement on the landscape. Here, we aim to understand how herbivores impact how fast plant populations spread through varying impacts on plant demography and dispersal. We strive to determine whether, and under what conditions, we see net positive effects of herbivores, in order to find scenarios where herbivores can help to promote spread. We draw on classic invasion theory to develop a stage-structured integrodifference equation model that incorporates herbivore impacts on plant demography and dispersal. We simulate seven herbivore "syndromes" (combinations of demographic and/or dispersal effects) drawn from the literature to understand how increasing herbivore pressure alters plant spreading speed. We find that herbivores with solely negative effects on plant demography or dispersal always slow plant spreading speed, and that the speed slows monotonically as herbivore pressure increases. However, we also find that plant spreading speed can be hump shaped with respect to herbivore pressure: plants spread faster in the presence of herbivores (for low herbivore pressure) and then slower (for high herbivore pressure). This result is robust, occurring across all syndromes in which herbivores have a positive effect on plant dispersal, and is a sign that the positive effects of herbivores on dispersal can outweigh their negative effects on demography. For all syndromes we find that sufficiently high herbivore pressure results in population collapse. Thus, our findings show that herbivores can speed up or slow down plant spread. These insights allow for a greater understanding of how to slow invasions, facilitate native species recolonization, and shape range shifts with global change.

Disturbance alters transience but nutrients determine equilibria during grassland succession with multiple global change drivers.

Disturbance and environmental change may cause communities to converge on a steady state, diverge towards multiple alternative states or remain in long-term transience. Yet, empirical investigations of successional trajectories are rare, especially in systems experiencing multiple concurrent anthropogenic drivers of change. We examined succession in old field grassland communities subjected to disturbance and nitrogen fertilization using data from a long-term (22-year) experiment. Regardless of initial disturbance, after a decade communities converged on steady states largely determined by resource availability, where species turnover declined as communities approached dynamic equilibria. Species favoured by the disturbance were those that eventually came to dominate the highly fertilized plots. Furthermore, disturbance made successional pathways more direct revealing an important interaction effect between nutrients and disturbance as drivers of community change. Our results underscore the dynamical nature of grassland and old field succession, demonstrating how community properties such as ß diversity change through transient and equilibrium states.

Show-Me Resilience: Assessing and Reconciling Rural Leaders' Perceptions of Climate Resilience in Missouri.

Rural areas of the United States play a vital role in coping with, adapting to and mitigating climate change, yet they often lag urban areas in climate planning and action. Rural leaders-e.g., policymakers, state/federal agency professionals, non-profit organization leadership, and scholars - are pivotal for driving the programs and policies that support resilient practices, but our understanding of their perspectives on climate resilience writ large is limited. We conducted semi-structured interviews with 23 rural leaders in Missouri to elucidate their conceptualizations of climate resilience and identify catalysts and constraints for climate adaptation planning and action across rural landscapes. We investigated participants' perceptions of the major vulnerabilities of rural communities and landscapes, threats to rural areas, and potential steps for making rural Missouri more resilient in the face of climate change. We found that most rural leaders conceptualized climate resilience as responding to hazardous events rather than anticipating or planning for hazardous trends. The predominant threats identified were flooding and drought, which aligns with climate projections for the Midwest. Participants proposed a wide variety of specific steps to enhance resilience but had the highest agreement about the utility of expanding existing programs. The most comprehensive suite of solutions was offered by participants who conceptualized resilience as involving social, ecological, and economic systems, underscoring the importance of broad thinking for developing more holistic solutions to climate-associated threats and the potential impact of greater collaboration across domains. We highlight and discuss a Missouri-based levee setback project that was identified by participants as a showcase of collaborative resilience-building.

Clarifying the effect of biodiversity on productivity in natural ecosystems with longitudinal data and methods for causal inference.

Causal effects of biodiversity on ecosystem functions can be estimated using experimental or observational designs - designs that pose a tradeoff between drawing credible causal inferences from correlations and drawing generalizable inferences. Here, we develop a design that reduces this tradeoff and revisits the question of how plant species diversity affects productivity. Our design leverages longitudinal data from 43 grasslands in 11 countries and approaches borrowed from fields outside of ecology to draw causal inferences from observational data. Contrary to many prior studies, we estimate that increases in plot-level species richness caused productivity to decline: a 10% increase in richness decreased productivity by 2.4%, 95% CI [-4.1, -0.74]. This contradiction stems from two sources. First, prior observational studies incompletely control for confounding factors. Second, most experiments plant fewer rare and non-native species than exist in nature. Although increases in native, dominant species increased productivity, increases in rare and non-native species decreased productivity, making the average effect negative in our study. By reducing the tradeoff between experimental and observational designs, our study demonstrates how observational studies can complement prior ecological experiments and inform future ones.

Deciding when to move.

Dandelion seeds respond to wet weather by closing their plumes, which reduces dispersal when wind conditions are poor.

The cost of self-promotion: ecological and demographic implications of the mentor effect in natural plant populations.

Under the mentor effect, compatible heterospecific pollen transfer induces self-pollen germination in otherwise self-incompatible plants. The mentor effect could be considered a novel mode of reproductive interference if it negatively impacts fitness. Yet to date, this phenomenon has predominately been investigated under experimental conditions rather than in situ. We address this gap in natural populations of the self-incompatible native dandelion, Taraxacum ceratophorum, where selfing only occurs in association with hybridization from exotic Taraxacum officinale. We tested whether self-fertilization rate increases in the hybrid zone, as predicted due to the mentor effect. Using results from these investigations, we created an exponential growth model to estimate the potential demographic impacts of the mentor effect on T. ceratophorum population growth. Our results demonstrate that the strength of the mentor effect in Taraxacum depends on the prevalence of pollinator-mediated outcross pollen deposition rather than self-pollination. Demographic models suggest that reduced outcrossing in T. ceratophorum under exotic invasion could negatively impact population growth through inbreeding depression. We demonstrate the mentor effect is rare in natural populations of T. ceratophorum due to masking by early life cycle inbreeding depression, prevalent outcrossing, and ovule usurpation by heterospecific pollen.

The effects of dispersal, herbivory, and competition on plant community assembly.

Dispersal is a key process in community assembly but is often considered separately from downstream assembly processes (e.g., competition, herbivory). However, dispersal varies by species and can interact with other assembly processes through establishment as species enter communities. Here, we sought to distinguish the role of dispersal in community assembly and its interaction with two biotic assembly processes: competition and herbivory. We used a tallgrass prairie restoration experiment that manipulated the competitive and herbivore environments while allowing for natural dispersal and establishment from a diverse regional species pool into areas of low diversity. Dispersal, competition, and herbivory all influenced local communities. By tracking the spread of four target species across the plots, we found interspecific and intraspecific differences in establishment patterns, with herbivores influencing the number of individuals present and the distances species moved. At the community level, only dispersal and competition significantly influenced alpha diversity, but all three processes additively influenced community composition. There was also evidence of herbivore-competition and herbivore-colonization trade-offs in our experiment. Some species that could tolerate herbivory were less likely to establish in competitive environments, while others that could tolerate herbivory were more likely to disperse greater distances. More work is needed to understand the contexts under which dispersal variation affects community assembly and its synergy with other processes.

EcoEvoApps: Interactive apps for theoretical models in ecology and evolutionary biology.

The integration of theory and data drives progress in science, but a persistent barrier to such integration in ecology and evolutionary biology is that theory is often developed and expressed in the form of mathematical models that can feel daunting and inaccessible for students and empiricists with variable quantitative training and attitudes towards math. A promising way to make mathematical models more approachable is to embed them into interactive tools with which one can visually evaluate model structures and directly explore model outcomes through simulation. To promote such interactive learning of quantitative models, we developed EcoEvoApps, a collection of free, open-source, and multilingual R/Shiny apps that include model overviews, interactive model simulations, and code to implement these models directly in R. The package currently focuses on canonical models of population dynamics, species interactions, and landscape ecology. These apps help illustrate fundamental results from theoretical ecology and can serve as valuable teaching tools in classroom settings. We present data from student surveys which show that students rate these apps as useful learning tools, and that using interactive apps leads to substantial gains in students' interest and confidence in working with mathematical models. This points to the potential for interactive activities to make theoretical models more accessible to a wider audience, and thus facilitate the feedback between theory and data across ecology and evolutionary biology.

Differential Trafficking and Expression of PIR Proteins in Acute and Chronic Plasmodium Infections.

Plasmodium multigene families are thought to play important roles in the pathogenesis of malaria. Plasmodium interspersed repeat (pir) genes comprise the largest multigene family in many Plasmodium species. However, their expression pattern and localisation remain to be elucidated. Understanding protein subcellular localisation is fundamental to reveal the functional importance and cell-cell interactions of the PIR proteins. Here, we use the rodent malaria parasite, Plasmodium chabaudi chabaudi, as a model to investigate the localisation pattern of this gene family. We found that most PIR proteins are co-expressed in clusters during acute and chronic infection; members of the S7 clade are predominantly expressed during the acute-phase, whereas members of the L1 clade dominate the chronic-phase of infection. Using peptide antisera specific for S7 or L1 PIRS, we show that these PIRs have different localisations within the infected red blood cells. S7 PIRs are exported into the infected red blood cell cytoplasm where they are co-localised with parasite-induced host cell modifications termed Maurer's clefts, whereas L1 PIRs are localised on or close to the parasitophorous vacuolar membrane. This localisation pattern changes following mosquito transmission and during progression from acute- to chronic-phase of infection. The presence of PIRs in Maurer's clefts, as seen for Plasmodium falciparum RIFIN and STEVOR proteins, might suggest trafficking of the PIRs on the surface of the infected erythrocytes. However, neither S7 nor L1 PIR proteins detected by the peptide antisera are localised on the surface of infected red blood cells, suggesting that they are unlikely to be targets of surface variant-specific antibodies or to be directly involved in adhesion of infected red blood cells to host cells, as described for Plasmodium falciparum VAR proteins. The differences in subcellular localisation of the two major clades of Plasmodium chabaudi PIRs across the blood cycle, and the apparent lack of expression on the red cell surface strongly suggest that the function(s) of this gene family may differ from those of other multigene families of Plasmodium, such as the var genes of Plasmodium falciparum.

Prospective Study of Withdrawal of Antiviral Therapy in Patients with Chronic Hepatitis B after Prolonged Virological Response.

Nucleoside analogue (NA) therapy for chronic hepatitis B (CHB) is associated with improved clinical outcomes, but usually requires long-term use. Whether treatment can be safely withdrawn and the factors associated with post-withdrawal outcome are not well defined. To assess long-term outcomes after stopping antiviral therapy, patients with hepatitis B e antigen (HBeAg)-negative CHB who had received antiviral therapy for 4 or more years with hepatitis B virus (HBV) DNA (≤100 IU/mL) were prospectively withdrawn from antiviral therapy and monitored monthly for the initial 6 months and every 3 months thereafter. Those with clinical relapse were retreated according to severity of relapse. Fifteen patients were withdrawn from lamivudine (4), adefovir (5), or a combination of the two (6) after a mean treatment duration of 8.4 years. The mean age was 45 years, 13 were male, and 8 were initially HBeAg-positive before treatment. After a mean follow-up of 6.6 years, outcomes differed by pretreatment HBeAg status. All patients who were HBeAg+ before treatment experienced virological relapse (8 of 8); 6 of 8 experienced clinical relapse; 4 of 8 had ALT flares; 5 of 8 required re-initiation of treatment, one of whom cleared hepatitis B surface antigen (HBsAg); and 3 of 8 remained off treatment, one of whom cleared HBsAg. In contrast, 4 of 7 patients who were HBeAg-negative before treatment experienced virological relapse, 3 of 7 experienced clinical relapse, and 1 of 7 had an alanine aminotransferase (ALT) flare. None restarted treatment, and 4 of 7 cleared HBsAg. Low pre-withdrawal HBsAg level was predictive of HBsAg loss. Conclusion: NA therapy can be safely withdrawn with long-term remission and high rates of HBsAg loss in most HBeAg-negative patients without cirrhosis. Patients who were initially HBeAg+ should not be withdrawn from treatment, because clinical relapse was frequent and often severe.