scholarly journals Age-Dependent Honey Bee Appetite Regulation Is Mediated by Trehalose and Octopamine Baseline Levels

Insects ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 863
Author(s):  
İrem Akülkü ◽  
Saleh Ghanem ◽  
Elif Filiztekin ◽  
Guntima Suwannapong ◽  
Christopher Mayack
Keyword(s):  
Honey Bee ◽  
Honey Bees ◽  
Appetite Regulation ◽  
Feedback Mechanisms ◽  
Age Dependent ◽  
Energetic State ◽  
Baseline Levels ◽  
The Individual ◽  
The Brain ◽  
Higher Sensitivity

There are multiple feedback mechanisms involved in appetite regulation, which is an integral part of maintaining energetic homeostasis. Older forager honey bees, in comparison to newly emerged bees and nurse bees, are known to have highly fluctuating hemolymph trehalose levels, higher appetite changes due to starvation, and higher octopamine levels in the brain. What remains unknown is if the hemolymph trehalose and octopamine levels interact with one another and how this varies as the bee ages. We manipulated trehalose and octopamine levels across age using physiological injections and found that nurse and forager bees increase their appetite levels due to increased octopamine levels in the brain. This is further enhanced by lower trehalose levels in the hemolymph. Moreover, nurse bees with high octopamine levels in the brain and low trehalose levels had the same appetite levels as untreated forager bees. Our findings suggest that the naturally higher levels of octopamine as the bee ages may result in higher sensitivity to fluctuating trehalose levels in the hemolymph that results in a more direct way of assessing the energetic state of the individual. Consequently, forager bees have a mechanism for more precise regulation of appetite in comparison to newly emerged and nurse bees.

scholarly journals Effects on Some Therapeutical, Biochemical, and Immunological Parameters of Honey Bee (Apis mellifera) Exposed to Probiotic Treatments, in Field and Laboratory Conditions

Insects ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 638
Author(s):  
Ivana Tlak Gajger ◽  
Josipa Vlainić ◽  
Petra Šoštarić ◽  
Janez Prešern ◽  
Jernej Bubnič ◽  
...  
Keyword(s):  
Honey Bee ◽  
Honey Bees ◽  
Immunological Parameters ◽  
Individual Level ◽  
Sugar Syrup ◽  
Novel Approach ◽  
The Individual ◽  
Field And Laboratory Conditions ◽  
Negative Factors ◽  
Bee Colonies

Several negative factors contribute to a decline in the number of insect pollinators. As a novel approach in therapy, we hypothesize that the EM® for bees could potentially have an important therapeutic and immunomodulatory effect on honey bee colonies. The aim of our study was to evaluate its impact on honey bees at the individual and colony level. This is the first appliance of the commercial probiotic mix EM® PROBIOTIC FOR BEES in honey bees as economically important social insects. The sugar syrup with 10% of probiotic was administered by spraying or feeding the honey bee colonies in the field conditions, in order to evaluate the infection levels with spores of Nosema spp. and colonies’ strength. Moreover, in laboratory-controlled conditions, in the hoarding cages, adult workers have been fed with sugar syrup supplemented with 2.5, 5, and 10% of EM® for bees for biochemical and immunological analyses of hemolymph, and with 5 and 10% for measuring the size of hypopharyngeal glands. It was found that following the EM® for bees administration the Nosema spp. spore counts in colonies were significantly reduced, and colonies’ strength was increased. The results at the individual level showed significant positive physiological changes in treated groups of adult bees, revealing at the same time a higher mortality rate when feeding sugar syrup supplemented with the probiotic.

scholarly journals The limits to exercise performance and the future of fatigue research

2012 ◽  
Vol 24 (1) ◽  
Author(s):  
FE Marino ◽  
M Gard ◽  
EJ Drinkwater
Keyword(s):  
Muscle Force ◽  
Subjective Assessment ◽  
Social Discourse ◽  
Experimental Paradigm ◽  
Sensory Cues ◽  
Feedback Mechanisms ◽  
Fatigue Process ◽  
Human Fatigue ◽  
The Individual ◽  
The Brain

The study of human fatigue stretches back centuries and remains a significant part of medical and social discourse. In the exercise sciences fatigue is routinely related to the ability to produce muscle force or to the recovery from force decrements. However, the study of fatigue has by virtue of the experimental paradigm excluded the subjective sense a person attributes to an event or experience, thus reducing our overall understanding of the fatigue process. Modern studies report the causes of fatigue as either central or peripheral in origin. Although useful, this dichotomy can also exclude the individual subjective assessment. Furthermore, adhering dogmatically to set parameters is likely limiting the advancement of our understanding. A more realistic paradigm would permit the individual to use the sensory cues to adjust the effort alongwith the fatigue process rather than rely purely on feedback mechanisms. Therefore, bringing feedforward mechanisms of the brain into fatigue research perhaps represents the next phase in the unravelling of the fatigue process.

scholarly journals Multi-tiered Analyses of Honey Bees That Resist or Succumb to Parasitic Mites and Viruses

2021 ◽  
Author(s):  
Daniel B. Weaver ◽  
Brandi L. Cantarel ◽  
Christine Elsik ◽  
Dawn L. Lopez ◽  
Jay Evans
Keyword(s):  
Gene Expression ◽  
Honey Bee ◽  
Honey Bees ◽  
Host Responses ◽  
Negative Effects ◽  
Pollination Services ◽  
Deformed Wing Virus ◽  
Mortality And Morbidity ◽  
The Individual ◽  
Parasitic Mites

Abstract Background Varroa destructor mites, and the numerous viruses they vector to their honey bee hosts, are among the most serious threats to honey bee populations, causing mortality and morbidity to both the individual honey bee and colony, the negative effects of which convey to the pollination services provided by honey bees worldwide. Here we use a combination of targeted assays and deep RNA sequencing to determine host and microbial changes in resistant and susceptible honey bee lineages. We focus on three study sets. The first involves field sampling of sympatric western bees, some derived from resistant stock and some from stock susceptible to mites. The second experiment contrasts three colonies more deeply, two from susceptible stock from the southeastern U.S. and one from mite-resistant bee stock from Eastern Texas. Finally, to decouple the effects of mites from those of the viruses they vector, we experimentally expose honey bees to DWV in the laboratory, measuring viral growth and host responses. Results We find strong differences between resistant and susceptible bees in terms of both viral loads and bee gene expression. Interestingly, lineages of bees with naturally low levels of the mite-vectored Deformed wing virus, also carried lower levels of viruses not vectored by mites. By mapping gene expression results against current ontologies and other studies, we describe the impacts of mite parasitism, as well as viruses on bee health against two genetic backgrounds. We identify numerous genes and processes seen in other studies of stress and disease in honey bee colonies, though we find novel genes and new patterns of expression too. Conclusions We provide evidence that honey bees surviving in the face of parasitic mites do so through their abilities to resist the presence of devastating viruses vectored by these mites. By revealing responses to viral infection and mite parasitism in different lineages, our data identify candidate proteins for the evolution of mite tolerance and virus resistance.

Modeling of Blood Flow in the Human Brain

2010 ◽  
Author(s):  
Md. Shahadat Hossain ◽  
Bhavin Dalal ◽  
Ian S. Fischer ◽  
Pushpendra Singh ◽  
Nadine Aubry
Keyword(s):  
Blood Flow ◽  
Human Brain ◽  
Flow Rate ◽  
Regulatory Mechanisms ◽  
Dimensional Model ◽  
Normal Range ◽  
One Dimensional ◽  
Baseline Levels ◽  
The Individual ◽  
The Brain

The non-Newtonian properties of blood, i.e., shear thinning and viscoelasticity, can have a significant influence on the distribution of Cerebral Blood Flow (CBF) in the human brain. The aim of this work is to quantify the role played by the non-Newtonian nature of blood. Under normal conditions, CBF is autoregulated to maintain baseline levels of flow and oxygen to the brain. However, in patients suffering from heart failure (HF), Stroke, or Arteriovenous malformation (AVM), the pressure in afferent vessels varies from the normal range within which the regulatory mechanisms can ensure a constant cerebral flow rate, leading to impaired cerebration in patients. It has been reported that the change in the flow rate is more significant in certain regions of the brain than others, and that this might be relevant to the pathophysiological symptoms exhibited in these patients. We have developed mathematical models of CBF under normal and the above disease conditions that use direct numerical simulations (DNS) for the individual capillaries along with the experimental data in a one-dimensional model to determine the flow rate and the methods for regulating CBF. The model also allows us to determine which regions of the brain would be affected relatively more severely under these conditions.

scholarly journals Pesticide–Virus Interactions in Honey Bees: Challenges and Opportunities for Understanding Drivers of Bee Declines

Viruses ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 566
Author(s):  
Gyan P. Harwood ◽  
Adam G. Dolezal
Keyword(s):  
Honey Bee ◽  
Honey Bees ◽  
Colony Losses ◽  
Challenges And Opportunities ◽  
Bee Health ◽  
Honey Bee Health ◽  
Varroa Mites ◽  
The Individual ◽  
Inadequate Nutrition ◽  
Virus Interactions

Honey bees are key agricultural pollinators, but beekeepers continually suffer high annual colony losses owing to a number of environmental stressors, including inadequate nutrition, pressures from parasites and pathogens, and exposure to a wide variety of pesticides. In this review, we examine how two such stressors, pesticides and viruses, may interact in additive or synergistic ways to affect honey bee health. Despite what appears to be a straightforward comparison, there is a dearth of studies examining this issue likely owing to the complexity of such interactions. Such complexities include the wide array of pesticide chemical classes with different modes of actions, the coupling of many bee viruses with ectoparasitic Varroa mites, and the intricate social structure of honey bee colonies. Together, these issues pose a challenge to researchers examining the effects pesticide-virus interactions at both the individual and colony level.

scholarly journals Pollen Diet—Properties and Impact on a Bee Colony

Insects ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 798
Author(s):  
Maciej Sylwester Bryś ◽  
Patrycja Skowronek ◽  
Aneta Strachecka
Keyword(s):  
Honey Bee ◽  
Honey Bees ◽  
Royal Jelly ◽  
Humoral Response ◽  
Single Species ◽  
Phenol Oxidase ◽  
Bee Colony ◽  
Secretory Immunity ◽  
Single Flower ◽  
The Individual

Diet is an important factor in the proper development of the individual and the entire colony. A pollen diet affects honey bees in a number of ways. It can stimulate the number and type of hemocytes, the total number of proteins, carbohydrates and lipids, affect the histology of the middle intestine, and ensure the correct ontogenesis of the larvae. Moreover, selected single-flower diets can stimulate the development of the pharyngeal glands that produce royal jelly, thus conditioning the development of secretory immunity. Selected single-species pollen may also increase the phenol oxidase concentration, which contributes to the humoral response. A honey bee diet based on multi-flower pollen is more desirable than a mono-flower diet, but must be properly balanced.

scholarly journals Tropilaelaps mercedesae parasitism changes behavior and gene expression in honey bee workers

2021 ◽  
Vol 17 (7) ◽  
pp. e1009684
Author(s):  
Jing Gao ◽  
Shilong Ma ◽  
Xinling Wang ◽  
Yang Yang ◽  
Qihua Luo ◽  
...  
Keyword(s):  
Gene Expression ◽  
Honey Bee ◽  
Honey Bees ◽  
Molecular Mechanisms ◽  
Sublethal Effects ◽  
Learning Ability ◽  
Flight Ability ◽  
Tropilaelaps Mercedesae ◽  
The Individual ◽  
Associated Function

Tropilaelaps mercedesae is one of the most problematic honey bee parasites and has become more threatening to the beekeeping industry. Tropilaelaps can easily parasitize immature honey bees (larvae and pupae) and have both lethal and sublethal effects on the individual worker bees. Our study for the first time experimentally assessed the effects of T. mercedesae on olfactory learning, flight ability, homing ability as well as transcriptional changes in parasitized adult honey bees. T. mercedesae infestation had negative impacts on olfactory associated function, flight ability, and homing rate. The volume of the mushroom body significantly increased in infested honey bees, which may be correlated to the lower sucrose responsiveness as well as lower learning ability in the infested bees. The gene expression involved in immune systems and carbohydrate transport and metabolism were significantly different between infested bees and non-infested bees. Moreover, genes function in cell adhesion play an essential role in olfactory sensory in honey bees. Our findings provide a comprehensive understanding of European honey bees in response to T. mercedesae infestation, and could be used to further investigate the complex molecular mechanisms in honey bees under parasitic stress.

scholarly journals Varroa destructor: how does it harm Apis mellifera honey bees and what can be done about it?

2020 ◽  
Vol 4 (1) ◽  
pp. 45-57 ◽  
Author(s):  
Amélie Noël ◽  
Yves Le Conte ◽  
Fanny Mondet
Keyword(s):  
Apis Mellifera ◽  
Honey Bee ◽  
Honey Bees ◽  
Varroa Destructor ◽  
Abiotic Factors ◽  
Apis Cerana ◽  
Management Strategies ◽  
Special Focus ◽  
Asian Honey Bee ◽  
The Individual

Since its migration from the Asian honey bee (Apis cerana) to the European honey bee (Apis mellifera), the ectoparasitic mite Varroa destructor has emerged as a major issue for beekeeping worldwide. Due to a short history of coevolution, the host–parasite relationship between A. mellifera and V. destructor is unbalanced, with honey bees suffering infestation effects at the individual, colony and population levels. Several control solutions have been developed to tackle the colony and production losses due to Varroa, but the burden caused by the mite in combination with other biotic and abiotic factors continues to increase, weakening the beekeeping industry. In this synthetic review, we highlight the main advances made between 2015 and 2020 on V. destructor biology and its impact on the health of the honey bee, A. mellifera. We also describe the main control solutions that are currently available to fight the mite and place a special focus on new methodological developments, which point to integrated pest management strategies for the control of Varroa in honey bee colonies.

scholarly journals Chronic Effects of Imidacloprid on Honey Bee Worker Development—Molecular Pathway Perspectives

2021 ◽  
Vol 22 (21) ◽  
pp. 11835
Author(s):  
Yun-Ru Chen ◽  
David T. W. Tzeng ◽  
En-Cheng Yang
Keyword(s):  
Honey Bee ◽  
Honey Bees ◽  
Muscle Development ◽  
Molecular Evidence ◽  
Somatic Muscle ◽  
Chronic Effects ◽  
Oxidation Reduction ◽  
Molecular Effects ◽  
The Individual

Sublethal dosages of imidacloprid cause long-term destructive effects on honey bees at the individual and colony levels. In this review, the molecular effects of sublethal imidacloprid were integrated and reported. Several general effects have been observed among different reports using different approaches. Quantitative PCR approaches revealed that imidacloprid treatments during the adult stage are expressed as changes in immuneresponse, detoxification, and oxidation-reduction response in both workers and queens. In addition, transcriptomic approaches suggested that phototransduction, behavior, and somatic muscle development also were affected. Although worker larvae show a higher tolerance to imidacloprid than adults, molecular evidence reveals its potential impacts. Sublethal imidacloprid treatment during the larval stage causes gene expression changes in larvae, pupae, and adults. Transcriptome profiles suggest that the population and functions of affected differentially expressed genes, DEGs, vary among different worker ages. Furthermore, an early transcriptomic switch from nurse bees to foragers was observed, suggesting that precocious foraging activity may occur. This report comprehensively describes the molecular effects of sublethal dosages of imidacloprid on the honey bee Apis mellifera. The corresponding molecular pathways for physiological and neurological responses in imidacloprid-exposed honey bees were validated. Transcriptomic evidence suggests a global and sustained sublethal impact of imidacloprid on honey bee development.

Fit Vs Faint: Assessing Work Causation in “Idiopathic Fall” Cases

2014 ◽  
Vol 19 (5) ◽  
pp. 3-12
Author(s):  
Lorne Direnfeld ◽  
David B. Torrey ◽  
Jim Black ◽  
LuAnn Haley ◽  
Christopher R. Brigham
Keyword(s):  
Blood Flow ◽  
Electrical Activity ◽  
Loss Of Consciousness ◽  
Brain Electrical Activity ◽  
Medical Terminology ◽  
Scientific Analysis ◽  
Medical Causation ◽  
The Individual ◽  
The Brain ◽  
Current Science

Abstract When an individual falls due to a nonwork-related episode of dizziness, hits their head and sustains injury, do workers’ compensation laws consider such injuries to be compensable? Bearing in mind that each state makes its own laws, the answer depends on what caused the loss of consciousness, and the second asks specifically what happened in the fall that caused the injury? The first question speaks to medical causation, which applies scientific analysis to determine the cause of the problem. The second question addresses legal causation: Under what factual circumstances are injuries of this type potentially covered under the law? Much nuance attends this analysis. The authors discuss idiopathic falls, which in this context means “unique to the individual” as opposed to “of unknown cause,” which is the familiar medical terminology. The article presents three detailed case studies that describe falls that had their genesis in episodes of loss of consciousness, followed by analyses by lawyer or judge authors who address the issue of compensability, including three scenarios from Arizona, California, and Pennsylvania. A medical (scientific) analysis must be thorough and must determine the facts regarding the fall and what occurred: Was the fall due to a fit (eg, a seizure with loss of consciousness attributable to anormal brain electrical activity) or a faint (eg, loss of consciousness attributable to a decrease in blood flow to the brain? The evaluator should be able to fully explain the basis for the conclusions, including references to current science.

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