Honey bee (Apis mellifera) colonies invest a substantial amount of colony resources in the production of drones during the reproductive season to enable mating with virgin queens from nearby ...colonies. Recent studies have shown significant differences in the production of sperm cells that are viable (i.e., sperm viability) and can fertilize an ovule among sexually mature drones that are exposed to different environmental conditions during development or as adults. In particular, sperm viability may be negatively affected during drone development from exposure to pesticides in contaminated beeswax. To assess whether sperm viability is negatively affected during drone development from exposure to beeswax contaminated with in-hive pesticides, we compared the viability of sperm collected from drones reared in pesticide-free beeswax with that of drones reared in beeswax contaminated with field-relevant concentrations of the pesticides most commonly found in wax from commercial beekeeping operations in the United States. These pesticides include the miticides fluvalinate, coumaphos and amitraz, and the agro-chemicals chlorothalonil and chlorpyrifos. Sperm from drones collected at 10 and 18 days post emergence were classified as viable or non-viable to calculate sperm viability. For all pesticide treatment groups, drones that were reared in pesticide-laden beeswax had lower sperm viability compared to those reared in pesticide-free beeswax. This difference was especially pronounced among drones reared in miticide-laden wax. Our results reinforce the notion that pesticide contamination of beeswax negatively affects the reproductive quality of drones, which can affect the queens they mate with, ultimately compromising colony health.
Foraging behavior in honey bees (Apis mellifera) is a complex phenotype that is regulated by physiological state and social signals. How these factors are integrated at the molecular level to ...modulate foraging behavior has not been well characterized. The transition of worker bees from nursing to foraging behaviors is mediated by large-scale changes in brain gene expression, which are influenced by pheromones produced by the queen and larvae. Larval pheromones can also stimulate foragers to leave the colony to collect pollen. However, the mechanisms underpinning this rapid behavioral plasticity in foragers that specialize in collecting pollen over nectar, and how larval pheromones impact these different behavioral states, remains to be determined. Here, we investigated the patterns of gene expression related to rapid behavioral plasticity and task allocation among honey bee foragers exposed to two larval pheromones, brood pheromone (BP) and (E)-beta-ocimene (EBO). We hypothesized that both pheromones would alter expression of genes in the brain related to foraging and would differentially impact brain gene expression depending on foraging specialization.
Combining data reduction, clustering, and network analysis methods, we found that foraging preference (nectar vs. pollen) and pheromone exposure are each associated with specific brain gene expression profiles. Furthermore, pheromone exposure has a strong transcriptional effect on genes that are preferentially expressed in nectar foragers. Representation factor analysis between our study and previous landmark honey bee transcriptome studies revealed significant overlaps for both pheromone communication and foraging task specialization.
Our results suggest that, as social signals, pheromones alter expression patterns of foraging-related genes in the bee's brain to increase pollen foraging at both long and short time scales. These results provide new insights into how social signals and task specialization are potentially integrated at the molecular level, and highlights the possible role that brain gene expression may play in honey bee behavioral plasticity across time scales.
A new study showcases the usefulness of systems theory and network analyses for understanding how dozens of stressors can act concomitantly to affect managed honey bee health. Interestingly, the most ...influential stressors are not those currently being addressed by beekeepers.
A new study showcases the usefulness of systems theory and network analyses for understanding how dozens of stressors can act concomitantly to affect managed honey bee health. Interestingly, the most influential stressors are not those currently being addressed by beekeepers.
Interspecies virus transmission involving economically important pollinators, including honey bees (Apis mellifera), has recently sparked research interests regarding pollinator health. Given that ...ants are common pests within apiaries in the southern U.S., the goals of this study were to (1) survey ants found within or near managed honey bee colonies, (2) document what interactions are occurring between ant pests and managed honey bees, and 3) determine if any of six commonly occurring honey bee-associated viruses were present in ants collected from within or far from apiaries. Ants belonging to 14 genera were observed interacting with managed honey bee colonies in multiple ways, most commonly by robbing sugar resources from within hives. We detected at least one virus in 89% of the ant samples collected from apiary sites (n = 57) and in 15% of ant samples collected at non-apiary sites (n = 20). We found that none of these ant samples tested positive for the replication of Deformed wing virus, Black queen cell virus, or Israeli acute paralysis virus, however. Future studies looking at possible virus transmission between ants and bees could determine whether ants can be considered mechanical vectors of honey bee-associated viruses, making them a potential threat to pollinator health.
For honey bees (Apis mellifera), colony maintenance and growth are highly dependent on worker foragers obtaining sufficient resources from flowering plants year round. Despite the importance of ...floral diversity for proper bee nutrition, urban development has drastically altered resource availability and diversity for these important pollinators. Therefore, understanding the floral resources foraged by bees in urbanized areas is key to identifying and promoting plants that enhance colony health in those environments. In this study, we identified the pollen foraged by bees in four developed areas of the U.S., and explored whether there were spatial or temporal differences in the types of floral sources of pollen used by honey bees in these landscapes. To do this, pollen was collected every month for up to one year from colonies located in developed (urban and suburban) sites in California, Texas, Florida, and Michigan, except during months of pollen dearth or winter. Homogenized pollen samples were acetolyzed and identified microscopically to the lowest taxonomic level possible. Once identified, each pollen type was classified into a frequency category based on its overall relative abundance. Species richness and diversity indices were also calculated and compared across states and seasons. We identified up to 64 pollen types belonging to 39 plant families in one season (California). Species richness was highest in CA and lowest in TX, and was highest during spring in every state. In particular, "predominant" and "secondary" pollen types belonged to the families Arecaceae, Sapindaceae, Anacardiaceae, Apiaceae, Asteraceae, Brassicaceae, Fabaceae, Fagaceae, Lythraceae, Myrtaceae, Rhamnaceae, Rosaceae, Rutaceae, Saliaceae, and Ulmaceae. This study will help broaden our understanding of honey bee foraging ecology and nutrition in urban environments, and will help promote the use of plants that serve the dual purpose of providing aesthetic value and nutritious forage for honey bee colonies placed in developed landscapes.
Purpose
The aim of this study was to determine the incidence and factors associated with the development of metastatic spinal cord compression (MSCC) after cervical cancer (CC).
Methods
This ...retrospective cohort of 3551 women with CC who underwent treatment at the Brazilian National Cancer Institute were included in the study. Clinical and sociodemographic variables were obtained from the Hospital Cancer Registry and from hospital records. A descriptive study of the population was carried out, using means and standard deviations or frequencies and percentages. The Kaplan–Meier curve was used to identify annual incidence rates. Associations between the independent variables and the outcome (MSCC) were evaluated by a univariate analysis, applying crude and adjusted odds ratios (aOR) assuming 95% confidence intervals.
Results
The MSCC incidence was of 1.5% (
n
= 51), associated to advanced staging (aOR = 2.65, 95% CI: 1.45–4.85,
p
= 0.001) and initial treatment with concomitant chemotherapy and radiotherapy (aOR = 4.40, 95% CI: 1.74–11.13,
p
= 0.002).
Conclusions
Our findings revealed the incidence and factors associated with MSCC, indicating a subset of patients who may be potential targets for the prevention and early treatment of this condition, indicating unprecedented and relevant data for the Brazilian epidemiological scenario due to the high CC incidence rates.
As the sole reproductive female in a honey bee (Apis mellifera) colony, the queen's health is critical to colony productivity and longevity. Beekeeping operations typically rely on the commercial ...mass production of queens for colony multiplication, which involves manipulating and isolating the queens by confining them in cages during early development. Using common queen-rearing techniques, this study shows that segregating newly eclosed queens from their worker attendants for 72 hours using queen protector cages has a significant impact on the total amount of gut bacteria carried by those queens compared to queens that have unrestricted access to attendants upon eclosion. Isolated virgin queens sampled immediately after isolation at 4 days post eclosure had significantly more bacteria and a less consistent microbiota composition than their non-isolated peers. Furthermore, this effect lasted into the mating life of queens, since mated queens that had been isolated after emergence and then sampled at 14 days post eclosure also had significantly more microbiota compared to non-isolated mated queens of the same age. The causes and potential impacts of this alteration are not clear and deserve further investigation. This study also verifies earlier findings that honey bee queens lack the core microbiome found within honey bee workers.
Conflict between genes inherited from the mother (matrigenes) and the father (patrigenes) is predicted to arise during social interactions among offspring if these genes are not evenly distributed ...among offspring genotypes. This intragenomic conflict drives parent-specific transcription patterns in offspring resulting from parent-specific epigenetic modifications. Previous tests of the kinship theory of intragenomic conflict in honey bees (Apis mellifera) provided evidence in support of theoretical predictions for variation in worker reproduction, which is associated with extreme variation in morphology and behavior. However, more subtle behaviors - such as aggression - have not been extensively studied. Additionally, the canonical epigenetic mark (DNA methylation) associated with parent-specific transcription in plant and mammalian model species does not appear to play the same role as in honey bees, and thus the molecular mechanisms underlying intragenomic conflict in this species is an open area of investigation. Here, we examined the role of intragenomic conflict in shaping aggression in honey bee workers through a reciprocal cross design and Oxford Nanopore direct RNA sequencing. We attempted to probe the underlying regulatory basis of this conflict through analyses of parent-specific RNA m6A and alternative splicing patterns. We report evidence that intragenomic conflict occurs in the context of honey bee aggression, with increased paternal and maternal allele-biased transcription in aggressive compared to non-aggressive bees, and higher paternal allele-biased transcription overall. However, we found no evidence to suggest that RNA m6A or alternative splicing mediate intragenomic conflict in this species.
The present work simulates the transport of oxygen, carbon dioxide, and carbon monoxide between a fetus's circulatory system and the mother's. The organ responsible for this exchange is the placenta. ...Carbon monoxide is a common air pollutant, and it impacts the physiological conditions even in low concentration. The impacts of carbon monoxide are especially dangerous for pregnant women, fetuses, and newborn babies. A model of carbon monoxide transport, from the literature, is modified to simulate a pregnant woman (original model was a male), therefore changing some parameters to express the adjusted respiratory system. It was considered the gas exchange in the placenta, to evaluate the concentration of these different gases in the fetus arterial and venous blood. Three methods of the exergy analysis are implemented for both mother and fetus respiratory systems, aiming at the comparison with the respiratory system of a male adult. The destroyed exergy of the literature did not have the same trend as the models proposed in this article, taking into consideration the hemoglobin reactions. In contrast, the entropy generation associated only with the diffusion transport phenomena was one order of magnitude lower than the other methods. The placenta destroyed exergy rate is significantly higher compared to the irreversibilities of the mother's respiratory system. One possible explanation is the fact that the placenta has other physiological functions than gas transportation.
Brazilian medicinal species of the Psidium genus are rich in secondary metabolites such as terpenes and phenolic compounds and present biological activities for several human diseases. For the native ...Psidium species, there are no specific research reports for any member of the genus about ethnobotanical research, hindering the joint analysis of its therapeutic indications together with the scientific evidence already investigated.
Analyze the therapeutic indications, the main chemical constituents, and the biological activities of native species of the Psidium to Brazil.
Systematic research was carried out in the Scopus, ScienceDirect, PubMed, and Web of Science databases over a period of ten years. Articles in English, Portuguese and Spanish were used. The research was divided into three phases, seeking information on ethnobotany, chemical composition and biological activities. The words were combined to structure the descriptors used in the search.
A total of 13 native species belonging to the Psidium genus were identified in this analysis, Psidium acutangulum DC., Psidium brownianum Mart. ex DC., Psidium cattleyanum Sabine, Psidium densicomum Mart. ex DC., Psidium grandifolium Mart. ex DC., Psidium guineense Sw., Psidium laruotteanum Cambess., Psidium myrsinites DC, Psidium myrtoides O. Berg, Psidium salutare (Kunth) O. Berg, Psidium schenckianum Kiaersk., Psidium sobralianum Proença & Landrum, Psidium striatulum Mart. ex DC. Of these, six were indicated in folk medicine, digestive system disorders being their main therapeutic indication. Most species presented an investigation of chemical composition and biological activity. They are rich in phenolic compounds, flavonoids, and terpenes and have antimicrobial, antioxidant, antiproliferative, and repellent activities.
Native species of the Psidium genus are important sources of active ingredients in combating adversities that affect the human health, especially regarding the digestive system. They have a rich chemical composition, responsible for the biological activities demonstrated for the species.
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