Coevolution of a generalist pathogen with many hosts: the case of the amphibian chytrid Batrachochytrium dendrobatidis.

Generalist pathogens maintain infectivity in numerous hosts; how this broad ecological niche impacts host-pathogen coevolution remains to be widely explored. Batrachochytrium dendrobatidis (Bd) is a highly generalist pathogenic fungus that has caused devastating declines in hundreds of amphibian species worldwide. This review examines amphibian chytridiomycosis host-pathogen interactions and available evidence for coevolution between Bd and its numerous hosts.

Chytrid infections exhibit historical spread and contemporary seasonality in a declining stream-breeding frog.

Species with extensive geographical ranges pose special challenges to assessing drivers of wildlife disease, necessitating collaborative and large-scale analyses. The imperilled foothill yellow-legged frog () inhabits a wide geographical range and variable conditions in rivers of California and Oregon (USA), and is considered threatened by the pathogen (Bd). To assess drivers of Bd infections over time and space, we compiled over 2000 datapoints from museum specimens (collected 1897-2005) and field samples (2005-2021) spanning 9° of latitude.

Tracking the Uneven Outcomes of COVID-19 on Racial and Ethnic Groups: Implications for Health Policy.

The socioeconomic shocks of the first COVID-19 pandemic wave disproportionately affected vulnerable groups. But did that trend continue to hold during the Delta and Omicron waves? Leveraging data from the Johns Hopkins Coronavirus Resource Center, this paper examines whether demographic inequalities persisted across the waves of COVID-19 infections. The current study utilizes fixed effects regressions to isolate the marginal relationships between socioeconomic factors with case counts and death counts.

The physician CEO advantage and hospital performance during the COVID-19 pandemic: capacity utilization and patient satisfaction.

Purpose: Prior studies have shown that physician-led hospitals have several advantages over non-physician-led hospitals. This study seeks to test whether these advantages also extend to periods of extreme disruptions such as the COVID-19 pandemic, which affect bed availability and hospital utilization.

Design/methodology/approach: The authors utilize a bounded Tobit estimation to identify differences in patient satisfaction rates and in-hospital utilization rates of top-rated hospitals in the United States.

Recommendations for empowering early career researchers to improve research culture and practice.

Early career researchers (ECRs) are important stakeholders leading efforts to catalyze systemic change in research culture and practice. Here, we summarize the outputs from a virtual unconventional conference (unconference), which brought together 54 invited experts from 20 countries with extensive experience in ECR initiatives designed to improve the culture and practice of science. Together, we drafted 2 sets of recommendations for (1) ECRs directly involved in initiatives or activities to change research culture and practice; and (2) stakeholders who wish to support ECRs in these efforts.

Endemic Lineages of Are Associated With Reduced Chytridiomycosis-Induced Mortality in Amphibians: Evidence From a Meta-Analysis of Experimental Infection Studies.

Emerging infectious wildlife diseases have caused devastating declines, particularly when pathogens have been introduced in naïve host populations. The outcome of disease emergence in any host population will be dictated by a series of factors including pathogen virulence, host susceptibility, and prior opportunity for coevolution between hosts and pathogens. Historical coevolution can lead to increased resistance in hosts and/or reduced virulence in endemic pathogens that allows stable persistence of host and pathogen populations.

Throwing caution to the wind: How hurricanes affect COVID-19 spread.

This study exploits the pathway of Hurricane Laura to assess its impact on the spread of COVID-19. Using US hospital data on confirmed and suspected adult COVID-19 cases, we find average daily cases per week rose by more than 12% primarily in tropical storm-affected counties in subsequent weeks. We suspect the key mechanisms involve constraints on social distancing for two reasons.

Habitat fragmentation in the Brazilian Atlantic Forest is associated with erosion of frog immunogenetic diversity and increased fungal infections.

Habitat fragmentation and infectious diseases threaten wildlife globally, but the interactions of these threats are poorly understood. For instance, while habitat fragmentation can impact genetic diversity at neutral loci, the impacts on disease-relevant loci are less well-studied. We examined the effects of habitat fragmentation in Brazil's Atlantic Forest on amphibian genetic diversity at an immune locus related to antigen presentation and detection (MHC IIB Exon 2).

Geography, Host Genetics, and Cross-Domain Microbial Networks Structure the Skin Microbiota of Fragmented Brazilian Atlantic Forest Frog Populations.

The host-associated microbiome plays a significant role in health. However, the roles of factors such as host genetics and microbial interactions in determining microbiome diversity remain unclear. We examined these factors using amplicon-based sequencing of 175 frog skin swabs collected from a naturally fragmented landscape in southeastern Brazil.

Demographics matter: the potentially disproportionate effect of COVID-19 on hospital ratings.

Objective: To identify how features of the community in which a hospital serves differentially relate to its patients' experiences based on the quality of that hospital.

Design: A Finite Mixture Model (FMM) is used to uncover a mix of two latent groups of hospitals that differ in quality. In the FMM, a multinomial logistic equation relates hospital-level factors to the odds of being in either group.

Skin microbiome correlates with bioclimate and Batrachochytrium dendrobatidis infection intensity in Brazil's Atlantic Forest treefrogs.

In Brazil's Atlantic Forest (AF) biodiversity conservation is of key importance since the fungal pathogen Batrachochytrium dendrobatidis (Bd) has led to the rapid loss of amphibian populations here and worldwide. The impact of Bd on amphibians is determined by the host's immune system, of which the skin microbiome is a critical component. The richness and diversity of such cutaneous bacterial communities are known to be shaped by abiotic factors which thus may indirectly modulate host susceptibility to Bd.

Provider-patient communication and hospital ratings: perceived gaps and forward thinking about the effects of COVID-19.

Objectives: To highlight clinical and operational issues, identify factors that shape patient responses in Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) and test the correlations between composite measures and overall hospital ratings.

Design: Responses to HCAHPS surveys were used in a partial correlation analysis to ascertain those HCAHPS composite measures that most relate to overall hospital ratings. The linear mean scores for the composite measures and individual and global items were analyzed with descriptive analysis and correlation analysis via JMP and SPSS statistical software.

Myelodysplastic syndromes: a review of therapeutic progress over the past 10 years.

Introduction: Myelodysplastic syndromes (MDS) represent a range of bone marrow disorders, with patients affected by cytopenias and risk of progression to AML. There are limited therapeutic options available for patients, including hypomethylating agents (azacitidine/decitabine), growth factor support, lenalidomide, and allogeneic stem cell transplant.

Areas Covered: This review provides an overview of the progress made over the past decade for emerging therapies for lower- and higher-risk MDS (MDS-HR).

The value of early physical maturity to young adult labor market outcomes.

Puberty is the most important developmental milestone closely preceding a young adult's labor market decisions. Thus, we examine the variation in the timing of physical maturity during adolescence to isolate its association with employment and hourly wages for US young adults. Using the National Longitudinal Study of Adolescent to Adult Health data, we find an early maturity premium of about 6% for females and 8% for males, but no employment advantage, in excess of gains from height and physical attractiveness.

Doctor-patient communication: a review and a rationale for using an assessment framework.

Purpose: The purpose of this paper is to explore the extent to which improving doctor-patient communication (DPC) can address and alleviate many healthcare delivery inefficiencies.

Design/methodology/approach: The authors survey causes and costs of miscommunication including perceptual gaps between how physicians believe they perform their communicative duties vs how patients feel and highlight thresholds such as the Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) used by hospitals to identify health outcomes and improve DPC.

Findings: The authors find that DPC correlates with better and more accurate care as well as with more satisfied patients.

Effect of Eye Opening on Single-Unit Activity and Local Field Potentials in the Subthalamic Nucleus.

Background: Subthalamic nucleus deep brain stimulation (STN DBS) is an established treatment in Parkinson's disease (PD). We investigate the effect of eye opening on neuronal activity and local field potentials (LFPs) in the STN.

Methods: We prospectively enrolled 25 PD patients undergoing STN DBS in our institution.

Evaluation of Quantitative Measurement Techniques for Head Tremor With Thalamic Deep Brain Stimulation.

Background: Ventralis intermedius thalamic deep brain stimulation (VIM DBS) has shown to be safe and effective for medically refractory essential tremor (ET). We evaluate the use of quantitative tremor measurement methods for head tremor in ET using a "smart" hat and a smartphone application.

Methods: We enrolled 13 ET patients who previously underwent VIM DBS.

The Effects of Mechanical and Thermal Stimuli on Local Field Potentials and Single Unit Activity in Parkinson's Disease Patients.

Background: Chronic pain is a major, debilitating symptom of Parkinson's disease (PD). Although, deep brain stimulation (DBS) has been shown to improve pain outcomes, the mechanisms underlying this phenomenon are unclear. Microelectrode recording allows us to measure both local field potentials (LFPs) and single neuronal unit activity (SUA).

Effect of low-frequency deep brain stimulation on sensory thresholds in Parkinson's disease.

OBJECTIVE Chronic pain is a major distressing symptom of Parkinson's disease (PD) that is often undertreated. Subthalamic nucleus (STN) deep brain stimulation (DBS) delivers high-frequency stimulation (HFS) to patients with PD and has been effective in pain relief in a subset of these patients. However, up to 74% of patients develop new pain concerns while receiving STN DBS.

Amphibian-killing chytrid in Brazil comprises both locally endemic and globally expanding populations.

Chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), is the emerging infectious disease implicated in recent population declines and extinctions of amphibian species worldwide. Bd strains from regions of disease-associated amphibian decline to date have all belonged to a single, hypervirulent clonal genotype (Bd-GPL). However, earlier studies in the Atlantic Forest of southeastern Brazil detected a novel, putatively enzootic lineage (Bd-Brazil), and indicated hybridization between Bd-GPL and Bd-Brazil.

Disentangling host, pathogen, and environmental determinants of a recently emerged wildlife disease: lessons from the first 15 years of amphibian chytridiomycosis research.

The amphibian fungal disease chytridiomycosis, which affects species across all continents, recently emerged as one of the greatest threats to biodiversity. Yet, many aspects of the basic biology and epidemiology of the pathogen, Batrachochytrium dendrobatidis (Bd), are still unknown, such as when and from where did Bd emerge and what is its true ecological niche? Here, we review the ecology and evolution of Bd in the Americas and highlight controversies that make this disease so enigmatic. We explore factors associated with variance in severity of epizootics focusing on the disease triangle of host susceptibility, pathogen virulence, and environment.

Effects of feral cats on the evolution of anti-predator behaviours in island reptiles: insights from an ancient introduction.

Exotic predators have driven the extinction of many island species. We examined impacts of feral cats on the abundance and anti-predator behaviours of Aegean wall lizards in the Cyclades (Greece), where cats were introduced thousands of years ago. We compared populations with high and low cat density on Naxos Island and populations on surrounding islets with no cats.