Explore the vast range of titles available.

A proposed strategy to aid in controlling the growing burden of vector-borne disease is population replacement, in which a natural vector population is replaced by a population with a reduced capacity for disease transmission. An important component of such a strategy is the drive system, which serves to spread a desired genotype into the targeted field population. Endosymbiotic Wolbachia bacteria are potential transgene drivers, but infections do not naturally occur in some important mosquito vectors, notably Aedes aegypti. In this work, stable infections of wAlbB Wolbachia were established in A. aegypti and caused high rates of cytoplasmic incompatibility (that is, elimination of egg hatch). Laboratory cage tests demonstrated the ability of wAlbB to spread into an A. aegypti population after seeding of an uninfected population with infected females, reaching infection fixation within seven generations.

Background Genomic analysis has revealed extensive contamination among laboratory-maintained microbes including malaria parasites, Mycobacterium tuberculosis , and Salmonella spp. Here, we provide direct evidence for recent contamination of a laboratory schistosome parasite population, and we investigate its genomic consequences. The Brazilian Schistosoma mansoni population SmBRE has several distinctive phenotypes, showing poor infectivity, reduced sporocyst number, low levels of cercarial shedding and low virulence in the intermediate snail host, and low worm burden and low fecundity in the vertebrate rodent host. In 2021 we observed a rapid change in SmBRE parasite phenotypes, with a 10-fold increase in cercarial production and fourfold increase in worm burden. Methods To determine the underlying genomic cause of these changes, we sequenced pools of SmBRE adults collected during parasite maintenance between 2015 and 2023. We also sequenced another parasite population (SmLE) maintained alongside SmBRE without phenotypic changes. Results While SmLE allele frequencies remained stable over the 8-year period, we observed sudden changes in allele frequency across the genome in SmBRE between July 2021 and February 2023, consistent with expectations of laboratory contamination. (i) SmLE-specific alleles increased in the SmBRE population from 0 to 41–46% across the genome between September and October 2021, reflecting the timing and magnitude of the contamination event. (ii) After contamination, strong selection ( s  ≅0.23) drove the replacement of low-fitness SmBRE with high-fitness SmLE alleles. (iii) Allele frequency changed rapidly across the whole genome, except for a region on chromosome 4, where SmBRE alleles remained at high frequency. Conclusions We were able to detect contamination in this case because SmBRE shows distinctive phenotypes. However, this would likely have been missed with phenotypically similar parasites. These results provide a cautionary tale about the importance of tracking the identity of parasite populations, but also showcase a simple approach to monitor changes within populations using molecular profiling of pooled population samples to characterize single-nucleotide polymorphisms. We also show that genetic drift results in continuous change even in the absence of contamination, causing parasites maintained in different labs (or sampled from the same lab at different times) to diverge. Graphical Abstract

Forest invasive alien species are a major threat to ecosystem stability and can have enormous economic and social impacts. For this reason, preventing the introduction of Asian gypsy moths (AGM; Lymantria dispar asiatica and L. d. japonica) into North America has been identified as a top priority by North American authorities. The AGM is an important defoliator of a wide variety of hardwood and coniferous trees, displaying a much broader host range and an enhanced dispersal ability relative to the already established European gypsy moth (L. d. dispar). Although molecular assays have been developed to help distinguish gypsy moth subspecies, these tools are not adequate for tracing the geographic origins of AGM samples intercepted on foreign vessels. Yet, this type of information would be very useful in characterizing introduction pathways and would help North American regulatory authorities in preventing introductions. The present proof‐of‐concept study assessed the potential of single nucleotide polymorphism (SNP) markers, obtained through genotyping by sequencing (GBS), to identify the geographic origins of gypsy moth samples. The approach was applied to eight laboratory‐reared gypsy moth populations, whose original stocks came from locations distributed over the entire range of L. dispar, comprising representatives of the three recognized subspecies. The various analyses we performed showed strong differentiation among populations (FST ≥ 0.237), enabling clear distinction of subspecies and geographic variants, while revealing introgression near the geographic boundaries between subspecies. This strong population structure resulted in 100% assignment success of moths to their original population when 2,327 SNPs were used. Although the SNP panels we developed are not immediately applicable to contemporary, natural populations because of distorted allele frequencies in the laboratory‐reared populations we used, our results attest to the potential of genomewide SNP markers as a tool to identify the geographic origins of intercepted gypsy moth samples.

Introduction: The brown marmorated stinkbug, Halyomorpha halys (Hemiptera: Pentatomidae), is native to East Asia, but also a widely invasive crop pest worldwide. It is essential to obtain sufficient samples of H. halys for developing effective management strategies. Terminating diapause for overwinter populations of H. halys and optimizing food sources for their progeny are crucial strategies for maintaining and expanding the indoor experiment colony. However, there are rarely reports on the rearing and keeping lab population of H. halys in its native Beijing. Methods: In this study, we collected overwintering adults of H. halys in northern China, terminated their diapause via low temperature storage and reared their progeny. Results: We found that a 3-week low temperature storage at 9°C was sufficient to induce oviposition in some females, albeit at a low egg production (0.17 ± 0.06 egg masses/female) and after a prolonged pre-oviposition period (25.2 ± 0.9 d). As the low temperature storage duration was extended, per-female egg production progressively increased, while the pre-oviposition period concurrently decreased. Egg production peaked at 1.23 ± 0.08 egg masses/female, and the pre-oviposition period reached a minimum of 14.6 ± 0.7 d after 28 weeks of storage. The survival rate of adult females, however, decreased with prolonged storage time, reaching a minimum of 24 ± 3.3% after 33 weeks of storage. The relationship between low-temperature storage time ( ) and population egg production (PF) is described by PF = a (−0.0006x2 + 0.0273x + 0.0130) (a: Number of insects introduced), and the maximum PF value was achieved by storing adults for 22.75 weeks. In laboratory rearing tests evaluating six diets for their effects on H. halys survival and egg production, both the highest nymphal survival rate (91.4 ± 3.3%) and the highest egg production (100.44 ± 8.05 eggs/female) occurred when stinkbugs were fed green beans, plus soybean seeds, and water. Conclusion: Optimal conditions for rearing H. halys collected in northern China were to maintain adults of the overwintering generation at 9 °C for 22.75 weeks, and then rear their progeny on green bean pods, supplemented with soybean seeds and water.

Understanding the risk factors that initiate cancer is essential for reducing the future cancer burden. Much of our current cancer control insight is from cohort studies and newer large-scale population laboratories designed to advance the science around precision oncology. Despite their promise for improving diagnosis and treatment outcomes, their current reductionist focus will likely have little impact shifting the cancer burden. However, it is possible that these big data assets can be adapted to have more impact on the future cancer burden through more focus on primary prevention efforts that incorporate artificial intelligence (AI) and machine learning (ML). ML automatically learns patterns and can devise complex models and algorithms that lend themselves to prediction in big data, revealing new unexpected relationships and pathways in a reliable and replicable fashion that otherwise would remain hidden given the complexities of big data. While AI has made big strides in several domains, the potential application in cancer prevention is lacking. As such, this commentary suggests that it may be time to consider the potential of AI within our existing cancer control population laboratories, and provides justification for why some small targeted investments to explore their impact on modelling existing real-time cancer prevention data may be a strategic cancer control opportunity.

Previous laboratory studies have demonstrated that insects can tolerate high temperatures by expressing inducible heat shock proteins (HSPs). This HSP-based tolerance, however, has seldom been studied under field conditions. Here, we cloned the HSP70 gene of Corythucha ciliata (Cchsp70), an invasive insect species with substantial thermal tolerance in subtropical China. We also compared the relative mRNA expression levels of Cchsp70 in response to controlled temperature treatments (2 h at 33-43 °C at 2 °C intervals in the laboratory) and to natural increases in temperature (08:00-14:00 at 2-h intervals, 29.7-37.2 °C) on a hot summer day in the field. The complete cDNA of Cchsp70 is 2256 bp long and has a 1917 bp open reading frame that encodes a protein (CcHSP70) with 639 amino acids. The expression levels of Cchsp70 significantly increased in response to high temperatures in both laboratory and field. At similar temperatures, however, the expression levels were much higher in the field than in the laboratory. These results suggest that CcHSP70 contributes to the thermal tolerance of C. ciliata and that factors in addition to thermal stress may induce Cchsp70 expression in the field.

Comparative data are provided on the strategies of homeostasis maintenance in laboratory populations of the silkworm Bombyx mori and the housefly Musca domestica. It is shown that selection for lifespan is associated with differentiation of reproductive strategies.

Background: Mental depression is an important health problem in many countries. It reduces productivity at work and is the fastest increasing reason for early retirement. Methods: This study followed up a Finnish cohort of 1726 men from 1984 to 2000. Depression was assessed at baseline by HPL depression score. Pension records were obtained from the national pension registers. Cox’s regression analysis was used to estimate the associations of depression with the risk of all disability pensions combined, separately for different causes of disability, and non-illness based pension. Results: During the follow up, 839 men (48.6%) received a disability pension. A total of 142 men (16.9% of all disability pensions) retired because of mental disorder and of these, 75 (52.8%) because of depression. After adjustment for the potential confounders, men in the highest third of depression score had an increased risk of non-illness based pension (RR 1.86 95% CI 1.37 to 2.51) and disability pension attributable to mental disorders (RR 2.74, 95% CI 1.68 to 4.46), chronic somatic diseases (RR 1.68, 95% CI 1.05 to 2.71), cardiovascular diseases (RR 1.61, 95% CI 1.12 to 2.32). The mean age of retirement for men with a high and low depression score was 57.6 years (SD 3.87) and 59.1 years (SD 3.65) (p<0.001) respectively. Conclusions: A high depression score predicted disability attributable to any cause, especially mental disorders, and non-illness based pensions. Depressed people retired on average 1.5 years younger than those without depression. Further studies are needed to elucidate the pathways of how mental depression leads people to seek retirement pension.

Assortative mating and hypervariability due to genomic stress caused by selection appear to be the main components of the mechanism of intrapopulation polymorphism maintenance. Activation of genomic transposable elements has significantly contributed to increasing variability provoked by inbreeding. An evaluation of the DNA copy number of transposon Hermes in somatic tissues of Musca domestica was conducted at all of the developmental stages in strains differing by lifespan. It was used as a criterion of genome stability.

Fluctuating asymmetry (FA, subtle random deviations from perfect bilateral symmetry) is often used as a measure of developmental instability (DI), which results from perturbations in developmental pathways caused by genetic or environmental stressors. During the present study, we estimated FA in 5 morphological traits, viz. wing length (WL), wing to thorax ratio (W:T), sternopleural bristle number (SBN), sex-comb tooth number (SCTN), and ovariole number (ON) in 18 laboratory populations of Drosophila ananassae. FA levels of measured traits differed significantly among populations except for SBN (in males and females) and W:T ratio (in females). Positional fluctuating asymmetry (PFA), a sensitive measure of DI, also varied significantly among the populations for SBN in females and SCTN in males. Interestingly, both males and females were similar for nonsexual traits. However, when FA across all traits (sexual and nonsexual) was combined into a single composite index (CFA), significant differences were found for both populations and sexes. Males showed higher CFA values than females, suggesting that males are more prone to developmental perturbations. The magnitude of FA differed significantly among traits, being lowest for nonsexual traits (SBN, WL, W:T ratio) and highest for sexual traits (SCTN and ON). The trait size of sexual traits (SCTN and ON) was positively correlated with their asymmetry. The possible reasons for variation in FA both among traits and among populations, and the usefulness of FA as an indicator of developmental stress and phenotypic quality in D. ananassae are discussed.