Examining Varroa-resistant Honey Bee Queens from Commercial Breeders: Colony Productivity, Hygienic Behavior, Suppression of Mite Reproduction, and the Relationship of Juvenile Hormone III to Mite Abundance

This research was conducted to assess the performance of commercially bred honey bee queens sold as resistant to the parasitic mite, Varroa destructor. The study’s objectives were to: 1) Compare honey and pollen stores and V. destructor infestation in colonies established with hybrid Russian, SMR, and control queens, 2) Determine levels of hygienic behavior and mite non-reproduction in the same colonies, and 3) Determine the relationship between juvenile hormone III in honey bee larvae and V. destructor reproduction. In Part One, when honey, pollen, and V. destructor levels were measured, no significant differences were found among types of queens. The similarity of V. destructor levels among study colonies with hybrid queens suggests that hybridization has diminished the effectiveness of the mite-resistance found in artificially inseminated mite-resistant queens. In Part Two, two traits associated with mite tolerance in honey bee colonies were measured, hygienic behavior and mite non-reproduction. Again, no significant differences were found in the levels of either trait among queen types. However, significant relationships were found between both traits and V. destructor concentrations in the colonies at the end of the season. Data suggest that, while the levels of resistant traits in hybrid SMR and Russian queens available from commercial breeders do not differ significantly from controls, these traits are present in the honey bee population as a whole and contribute to lower parasite infestations. In Part Three, the possible influence of honey bee juvenile hormone III levels on V. destructor reproduction was examined. A short test was conducted to determine juvenile hormone titers during the honey bee’s fifth larval instar, a period coincident with initial mite feeding. Radioimmunoassay was used to detect juvenile hormone in the bees’ hemolymph. Positive relationships were found between juvenile hormone titers and V. destructor reproduction and between juvenile hormone titers and V. destructor concentration in the colonies at the end of the season. Results suggest that low host juvenile hormone levels might diminish the reproductive capacity of the Varroa mite, both in terms of absolute non-reproduction and in reduced fecundity. Recommendations are made to queen breeders for the increased use of Varroa-resistant drones in mating yards to ensure the preservation of resistant traits in hybrid queens. Broader studies of juvenile hormone and V. destructor reproduction are also recommended

Supercolonial structure of invasive populations of the tawny crazy ant Nylanderia fulva in the US

Background: Social insects are among the most serious invasive pests in the world, particularly successful at monopolizing environmental resources to outcompete native species and achieve ecological dominance. The invasive success of some social insects is enhanced by their unicolonial structure, under which the presence of numerous queens and the lack of aggression against non-nestmates allow high worker densities, colony growth, and survival while eliminating intra-specific competition. In this study, we investigated the population genetics, colony structure and levels of aggression in the tawny crazy ant, Nylanderia fulva, which was recently introduced into the United States from South America. Results: We found that this species experienced a genetic bottleneck during its invasion lowering its genetic diversity by 60%. Our results show that the introduction of N. fulva is associated with a shift in colony structure. This species exhibits a multicolonial organization in its native range, with colonies clearly separated from one another, whereas it displays a unicolonial system with no clear boundaries among nests in its invasive range. We uncovered an absence of genetic differentiation among populations across the entire invasive range, and a lack of aggressive behaviors towards conspecifics from different nests, even ones separated by several hundreds of kilometers. Conclusions: Overall, these results suggest that across its entire invasive range in the U.S.A., this species forms a single supercolony spreading more than 2000 km. In each invasive nest, we found several, up to hundreds, of reproductive queens, each being mated with a single male. The many reproductive queens per nests, together with the free movement of individuals between nests, leads to a relatedness coefficient among nestmate workers close to zero in introduced populations, calling into question the stability of this unicolonial system in which indirect fitness benefits to workers is apparently absent.Fil: Eyer, Pierre André. Texas A&M University; Estados UnidosFil: McDowell, Bryant. Texas A&M University; Estados UnidosFil: Johnson, Laura N. L.. Texas A&M University; Estados UnidosFil: Calcaterra, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación para el Estudio de Especies Invasivas; ArgentinaFil: Fernández, María Belén. Fundación para el Estudio de Especies Invasivas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Shoemaker, Dewayne. University of Tennessee; Estados UnidosFil: Puckett, Robert T.. Texas A&M University; Estados UnidosFil: Vargo, Edward L.. Texas A&M University; Estados Unido

DNA Damage and Cytokine Production in Non-Target Irradiated Lymphocytes

In advanced radiotherapy, treatment of the tumor with high-intensity modulated fields is balanced with normal tissue sparing. However, the non-target dose delivered to surrounding healthy tissue within the irradiated volume is a potential cause for concern. Whether the effects observed are caused after exposure to out-of-field radiation or bystander effects through neighboring irradiated cells is not fully understood. The goal of this study was to determine the effect of exposure to out-of-field radiation in lymphocyte cell lines and primary blood cells. The role of cellular radiosensitivity in altering bystander responses in out-of-field exposed cells was also investigated. Target cells were positioned in a phantom in the center of the radiation field (in-field dose) and exposed to 2 Gy irradiation. Lymphocyte cell lines (C1, AT3ABR, Jurkat, THP-1, AT2Bi and AT3Bi) and peripheral blood were placed 1 cm away from the radiation field edge (out-offield dose) and received an average dose of 10.8 6 4.2 cGy. Double-stranded DNA damage, cell growth and gene expression were measured in the out-of-field cells. Radiosensitive AT3ABR and primary blood cells demonstrated the largest increase in c-H2AX foci after irradiation. Exposure of normal cells to bystander factors from irradiated radiosensitive cell lines also increased DNA damage. Expression of IL-1, IL-6, TNFa and TGFb after addition of bystander factors from radiosensitive cells showed differential effects in normally responding cells, with some evidence of an adaptive response observed. Exposure to out-of-field radiation induces DNA damage and reduces growth in radiosensitive cells. Bystander factors produced by directly irradiated cells in combination with out-of-field exposure may upregulate pro- and anti-inflammatory genes in responding cells of different radiosensitivities, with the potential of affecting the tumor microenvironment. A greater understanding of the radiobiological response in normal cells outside the primary treatment field would assist in radiation treatment planning and in reducing early and late toxicities

MicroRNA Analysis of ATM-Deficient Cells Indicate PTEN and CCDN1 as Potential Biomarkers of Radiation Response

Genetic and epigenetic profile changes associated with individual radiation sensitivity are well documented and have led to enhanced understanding of the mechanisms of the radiation-induced DNA damage response. However, the search continues to identify reliable biomarkers of individual radiation sensitivity. Herein, we report on a multi-biomarker approach using traditional cytogenetic biomarkers, DNA damage biomarkers and transcriptional microRNA (miR) biomarkers coupled with their potential gene targets to identify radiosensitivity in ataxia-telangiectasia mutated (ATM)-deficient lymphoblastoid cell lines (LCL); ATM-proficient cell lines were used as controls. Cells were 0.05 and 0.5 Gy irradiated, using a linear accelerator, with sham-irradiated cells as controls. At 1 h postirradiation, cells were fixed for γ-H2AX analysis as a measurement of DNA damage, and cytogenetic analysis using the G2 chromosomal sensitivity assay, G-banding and FISH techniques. RNA was also isolated for genetic profiling by microRNA (miR) and RT-PCR analysis. A panel of 752 miR were analyzed, and potential target genes, phosphatase and tensin homolog (PTEN) and cyclin D1 (CCND1), were measured. The cytogenetic assays revealed that although the control cell line had functional cell cycle checkpoints, the radiosensitivity of the control and AT cell lines were similar. Analysis of DNA damage in all cell lines, including an additional control cell line, showed elevated γ-H2AX levels for only one AT cell line. Of the 752 miR analyzed, eight miR were upregulated, and six miR were downregulated in the AT cells compared to the control. Upregulated miR-152-3p, miR-24-5p and miR-92-15p and all downregulated miR were indicated as modulators of PTEN and CCDN1. Further measurement of both genes validated their potential role as radiation-response biomarkers. The multi-biomarker approach not only revealed potential candidates for radiation response, but provided additional mechanistic insights into the response in AT-deficient cells

Cohort Profile: The United Kingdom Research study into Ethnicity and COVID-19 outcomes in Healthcare workers (UK-REACH)

The UK-REACH cohort was established to understand why ethnic minority healthcare workers (HCWs) are at risk of poorer outcomes from COVID-19 when compared with their White ethnic counterparts in the UK. Through study design, it contains a uniquely high percentage of participants from ethnic minority backgrounds about whom a wide range of qualitative and quantitative data have been collected. A total of 17 891 HCWs aged 16–89 years (mean age: 44) have been recruited from across the UK via all major healthcare regulators, individual National Health Service hospital trusts and UK HCW membership bodies who advertised the study to their registrants/staff to encourage participation in the study. Data available include linked healthcare records for 25 years from the date of consent and consent to obtain genomic sequencing data collected via saliva. Online questionnaires include information on demographics, COVID-19 exposures at work and home, redeployment in the workforce due to COVID-19, mental health measures, workforce attrition and opinions on COVID-19 vaccines, with baseline (n = 15 119), 6 (n = 5632) and 12-month follow-up (n = 6535) data captured. Request data access and collaborations by following documentation found at https://www.uk-reach.org/main/data_sharing

Healthcare workers’ views on mandatory SARS-CoV-2 vaccination in the UK: A cross-sectional, mixed-methods analysis from the UK-REACH study

Background: Several countries now have mandatory SARS-CoV-2 vaccination for healthcare workers (HCWs) or the general population. HCWs’ views on this are largely unknown. Using data from the nationwide UK-REACH study we aimed to understand UK HCW's views on improving SARS-CoV-2 vaccination coverage, including mandatory vaccination. // Methods: Between 21st April and 26th June 2021, we administered an online questionnaire via email to 17 891 UK HCWs recruited as part of a longitudinal cohort from across the UK who had previously responded to a baseline questionnaire (primarily recruited through email) as part of the United Kingdom Research study into Ethnicity And COVID-19 outcomes in Healthcare workers (UK-REACH) nationwide prospective cohort study. We categorised responses to a free-text question “What should society do if people do not get vaccinated against COVID-19?” using qualitative content analysis. We collapsed categories into a binary variable: favours mandatory vaccination or not, using logistic regression to calculate its demographic predictors, and its occupational, health, and attitudinal predictors adjusted for demographics. // Findings: Of 5633 questionnaire respondents, 3235 answered the free text question. Median age of free text responders was 47 years (IQR 36–56) and 2705 (74.3%) were female. 18% (n = 578) favoured mandatory vaccination (201 [6%] participants for HCWs and others working with vulnerable populations; 377 [12%] for the general population), but the most frequent suggestion was education (32%, n = 1047). Older HCWs (OR 1.84; 95% CI 1.44–2.34 [≥55 years vs 16 years to <40 years]), HCWs vaccinated against influenza (OR 1.49; 95% CI 1.11–2.01 [2 vaccines vs none]), and with more positive vaccination attitudes generally (OR 1.10; 95% CI 1.06–1.15) were more likely to favour mandatory vaccination, whereas female HCWs (OR= 0.79, 95% CI 0.63–0.96, vs male HCWs) and Black HCWs (OR=0.46, 95% CI 0.25–0.85, vs white HCWs) were less likely to. // Interpretation: Only one in six of the HCWs in this large, diverse, UK-wide sample favoured mandatory vaccination. Building trust, educating, and supporting HCWs who are hesitant about vaccination may be more acceptable, effective, and equitable

Access to personal protective equipment in healthcare workers during the COVID-19 pandemic in the United Kingdom: results from a nationwide cohort study (UK-REACH)

BACKGROUND: Healthcare workers (HCWs) are at high risk of SARS-CoV-2 infection. Effective use of personal protective equipment (PPE) reduces this risk. We sought to determine the prevalence and predictors of self-reported access to appropriate PPE (aPPE) for HCWs in the UK during the COVID-19 pandemic. METHODS: We conducted cross sectional analyses using data from a nationwide questionnaire-based cohort study administered between December 2020-February 2021. The outcome was a binary measure of self-reported aPPE (access all of the time vs access most of the time or less frequently) at two timepoints: the first national lockdown in the UK in March 2020 (primary analysis) and at the time of questionnaire response (secondary analysis). RESULTS: Ten thousand five hundred eight HCWs were included in the primary analysis, and 12,252 in the secondary analysis. 35.2% of HCWs reported aPPE at all times in the primary analysis; 83.9% reported aPPE at all times in the secondary analysis. In the primary analysis, after adjustment (for age, sex, ethnicity, migration status, occupation, aerosol generating procedure exposure, work sector and region, working hours, night shift frequency and trust in employing organisation), older HCWs and those working in Intensive Care Units were more likely to report aPPE at all times. Asian HCWs (aOR:0.77, 95%CI 0.67-0.89 [vs White]), those in allied health professional and dental roles (vs those in medical roles), and those who saw a higher number of COVID-19 patients compared to those who saw none (≥ 21 patients/week 0.74, 0.61-0.90) were less likely to report aPPE at all times. Those who trusted their employing organisation to deal with concerns about unsafe clinical practice, compared to those who did not, were twice as likely to report aPPE at all times. Significant predictors were largely unchanged in the secondary analysis. CONCLUSIONS: Only a third of HCWs in the UK reported aPPE at all times during the first lockdown and that aPPE had improved later in the pandemic. We also identified key determinants of aPPE during the first UK lockdown, which have mostly persisted since lockdown was eased. These findings have important implications for the safe delivery of healthcare during the pandemic

Arachidonic acid mediates the formation of abundant alpha-helical multimers of alpha-synuclein

The protein alpha-synuclein (αS) self-assembles into toxic beta-sheet aggregates in Parkinson’s disease, while it is proposed that αS forms soluble alpha-helical multimers in healthy neurons. Here, we have made αS multimers in vitro using arachidonic acid (ARA), one of the most abundant fatty acids in the brain, and characterized them by a combination of bulk experiments and single-molecule Fӧrster resonance energy transfer (sm-FRET) measurements. The data suggest that ARA-induced oligomers are alpha-helical, resistant to fibril formation, more prone to disaggregation, enzymatic digestion and degradation by the 26S proteasome, and lead to lower neuronal damage and reduced activation of microglia compared to the oligomers formed in the absence of ARA. These multimers can be formed at physiologically-relevant concentrations, and pathological mutants of αS form less multimers than wild-type αS. Our work provides strong biophysical evidence for the formation of alpha-helical multimers of αS in the presence of a biologically relevant fatty acid, which may have a protective role with respect to the generation of beta-sheet toxic structures during αS fibrillation.M.I. acknowledges Dr. Tayyeb-Hussain Scholarship. L.T. has been recipient of a grant PAT Post Doc Outgoing 2009 7th Framework Program Marie Curie COFUND actions. C.D.H. and C.E.B. acknowledge funding from Alzheimer’s Research UK. Augustus Newman Foundation is acknowledged

Allosteric “beta-blocker” isolated from a DNA-encoded small molecule library

The present study reports the discovery of a small-molecule negative allosteric modulator for the β2-adrenergic receptor (β2AR) via in vitro affinity-based iterative selection of highly diverse DNA-encoded small-molecule libraries. Characterization of the compound demonstrates its selectivity for the β2AR and that it negatively modulates a wide range of receptor functions. More importantly, our findings establish a generally applicable, proof-of-concept strategy for screening DNA-encoded small-molecule libraries against purified G-protein–coupled receptors (GPCRs), which holds great potential for discovering therapeutic molecules

International meta-analysis of PTSD genome-wide association studies identifies sex- and ancestry-specific genetic risk loci.

The risk of posttraumatic stress disorder (PTSD) following trauma is heritable, but robust common variants have yet to be identified. In a multi-ethnic cohort including over 30,000 PTSD cases and 170,000 controls we conduct a genome-wide association study of PTSD. We demonstrate SNP-based heritability estimates of 5-20%, varying by sex. Three genome-wide significant loci are identified, 2 in European and 1 in African-ancestry analyses. Analyses stratified by sex implicate 3 additional loci in men. Along with other novel genes and non-coding RNAs, a Parkinson's disease gene involved in dopamine regulation, PARK2, is associated with PTSD. Finally, we demonstrate that polygenic risk for PTSD is significantly predictive of re-experiencing symptoms in the Million Veteran Program dataset, although specific loci did not replicate. These results demonstrate the role of genetic variation in the biology of risk for PTSD and highlight the necessity of conducting sex-stratified analyses and expanding GWAS beyond European ancestry populations