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1.
J Insect Sci ; 23(5)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37815893

RESUMO

Many Canadian beekeepers replace a subset of their honey bee queens annually. However, introducing a new queen to a honey bee colony is a management practice with a high degree of uncertainty. Despite the consensus that it is most effective to introduce queens to queenless colonies, some commercial beekeepers claim success with introducing queen cells into the honey super of queenright colonies. We tested the success rate of this practice by introducing queen cells to 100 queenright colonies in southern Alberta during a honey flow. The genotypes of the resultant offspring drones were determined using the microsatellite marker A76 to identify their laying queen mothers. Our results show that new queens successfully supersede original queens in 6% of queenright colonies, suggesting that the practice does not result in the new queen taking over leadership in most colonies. Additionally, supersedure by daughter queens is more common (13%) than new queen supersedure when introducing queen cells to queenright colonies during a honey flow. However, there could be a benefit to the practice of requeening queenright colonies with queen cells in honey supers if the colonies that accepted a new queen (whether a daughter of or unrelated to the old queen) were colonies with a failing queen.


Assuntos
Mel , Abelhas , Animais , Canadá , Repetições de Microssatélites , Genótipo
2.
J Vet Med Educ ; 47(5): 619-631, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33231519

RESUMO

Limitations in workforce size and access to resources remain perennial challenges to greater progress in academic veterinary medicine and engagement between human and veterinary medicine (One Health). Ongoing resource constraints occur in part due to limited public understanding of the role veterinarians play in improving human health. One Health interactions, particularly through interdisciplinary collaborations in biomedical research, present constructive opportunities to inform resource policies and advance health care. To this end, inter-institutional partnerships between individual veterinary medical education programs (VMEPs) and several National Institutes of Health (NIH) intramural research programs have created synergies beyond those provided by individual programs. In the NIH Comparative Biomedical Scientist Training Program (CBSTP), interdisciplinary cross-training of veterinarians consisting of specialty veterinary medicine coupled with training in human disease research leading to a PhD, occurs collaboratively on both VMEP and NIH campuses. Pre-doctoral veterinary student research opportunities have also been made available. Through the CBSTP, NIH investigators and national biomedical science policy makers gain access to veterinary perspective and expertise, while veterinarians obtain additional opportunities for NIH-funded research training. CBSTP Fellows serve as de facto ambassadors enhancing visibility for the profession while in residence at NIH, and subsequently through a variety of university, industry, and government research appointments, as graduates. Thus, the CBSTP represents an inter-institutional opportunity that not only addresses critical needs for veterinarian-scientists in the biomedical workforce, but also simultaneously exposes national policy makers to veterinarian-scientists' specialized training, leading to more effective realization of One Health goals to benefit human and animal health.


Assuntos
Pesquisa Biomédica , Educação em Veterinária , Saúde Única , Médicos Veterinários , Animais , Objetivos , Humanos , National Institutes of Health (U.S.) , Estados Unidos
3.
J Invertebr Pathol ; 146: 24-30, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28400199

RESUMO

We examined whether alfalfa leafcutting bees (ALCB, Megachille rotundata) experienced a higher incidence of seven viruses commonly found honey bees (Apis mellifera) when placed alongside honey bees for hybrid canola seed pollination. Although two viruses - sacbrood virus (SBV) and deformed wing virus (DWV) - were detected in ALCB adults, their presence appeared independent of whether honey bees were present in the same field or not. A further survey of viruses among ALCB adults in three different alfalfa seed growing regions in Western Canada confirmed the ubiquity of sacbrood virus (SBV) as well as the infrequent presence of acute bee paralysis virus (ABPV), both of which had not been previously reported on ALCB. Moreover, SBV and ABPV were detected in the cocoon stage and only in one region. Co-infection among pools of ALCB adults with both of these viruses was more closely correlated with decreasing levels of cocoon viability than infection levels in cocoons themselves. This research suggests ongoing viral transmission between honey bees and ALCB in the same fields is likely low but that co-infection with these viruses may lower ALCB productivity.


Assuntos
Abelhas/virologia , Vírus de Insetos/patogenicidade , Animais , Canadá , Vírus de Insetos/classificação , Vírus de Insetos/isolamento & purificação , Especificidade da Espécie
4.
J Immunol ; 191(4): 1692-703, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23858034

RESUMO

Generation of high-affinity Abs in response to Ags/infectious agents is essential for developing long-lasting immune responses. B cell maturation and Ab responses to Ag stimulation require Ig somatic hypermutation (SHM) and class-switch recombination (CSR) for high-affinity responses. Upon immunization with either the model Ag 4-hydroxy-3-nitrophenylacetyl hapten (NP) conjugated to chicken γ globulin lysine (NP-CGG) or heat-killed Streptococcus pneumoniae capsular type 14 protein (Pn14), knock-in (KI) mice hypomorphic for mTOR function had a decreased ability to form germinal centers, develop high-affinity anti-NP-specific or anti-Pn14-specific Abs, and perform SHM/CSR. Hypomorphic mTOR mice also had a high mortality (40%) compared with wild-type (WT) (0%) littermates and had lower pneumococcal surface protein A-specific Ab titers when immunized and challenged with live S. pneumoniae infection. Mice with mTOR deleted in their B cell lineage (knockout [KO]) also produced fewer splenic germinal centers and decreased high-affinity Ab responses to NP-CGG than did their WT littermates. CSR rates were lower in mTOR KI and KO mice, and pharmacologic inhibition of mTOR in WT B cells resulted in decreased rates of ex vivo CSR. RNA and protein levels of activation-induced cytidine deaminase (AID), a protein essential for SHM and CSR, were lower in B cells from both KI and B cell-specific KO mice, concomitant with increases in phosphorylated AKT and FOXO1. Rescue experiments increasing AID expression in KI B cells restored CSR levels to those in WT B cells. Thus, mTOR plays an important immunoregulatory role in the germinal center, at least partially through AID signaling, in generating high-affinity Abs.


Assuntos
Diversidade de Anticorpos , Formação de Anticorpos , Linfócitos B/imunologia , Citidina Desaminase/imunologia , Serina-Treonina Quinases TOR/imunologia , Animais , Anticorpos Antibacterianos/biossíntese , Anticorpos Antibacterianos/imunologia , Afinidade de Anticorpos , Cápsulas Bacterianas/imunologia , Linhagem da Célula , Ativação Enzimática , Técnicas de Introdução de Genes , Centro Germinativo/imunologia , Centro Germinativo/patologia , Haptenos/imunologia , Abrigo para Animais , Imunização , Switching de Imunoglobulina , Imunoglobulina G/imunologia , Camundongos , Camundongos Knockout , Nitrofenóis/imunologia , Fenilacetatos/imunologia , Transdução de Sinais/imunologia , Hipermutação Somática de Imunoglobulina , Baço/imunologia , Baço/patologia , Infecções Estreptocócicas/imunologia , Streptococcus pneumoniae/imunologia
5.
BMC Dev Biol ; 14: 24, 2014 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-24886590

RESUMO

BACKGROUND: Chloride Intracellular Channel 4 (CLIC4) is one of seven members in the closely related CLIC protein family. CLIC4 is involved in multiple cellular processes including apoptosis, cellular differentiation, inflammation and endothelial tubulogenesis. Despite over a decade of research, no comprehensive in situ expression analysis of CLIC4 in a living organism has been reported. In order to fulfill this goal, we generated a knock-in mouse to express Green Fluorescent Protein (GFP) from the CLIC4 locus, thus substituting the GFP coding region for CLIC4. We used GFP protein expression to eliminate cross reaction with other CLIC family members. RESULTS: We analyzed CLIC4 expression during embryonic development and adult organs. During mid and late gestation, CLIC4 expression is modulated particularly in fetal brain, heart, thymus, liver and kidney as well as in developing brown adipose tissue and stratifying epidermis. In the adult mouse, CLIC4 is highly expressed globally in vascular endothelial cells as well as in liver, lung alveolar septae, pancreatic acini, spermatogonia, renal proximal tubules, cardiomyocytes and thymic epithelial cells. Neural expression included axonal tracks, olfactory bulb, Purkinje cell layer and dentate gyrus. Renal CLIC4 expression was most pronounced in proximal tubules, although altered renal function was not detected in the absence of CLIC4. Myeloid cells and B cells of the spleen are rich in CLIC4 expression as are CD4 and CD8 positive T cells. CONCLUSIONS: In a comprehensive study detailing CLIC4 expression in situ in a mouse model that excludes cross reaction with other family members, we were able to document previously unreported expression for CLIC4 in developing fetus, particularly the brain. In addition, compartmentalized expression of CLIC4 in specific adult tissues and cells provides a focus to explore potential functions of this protein not addressed previously.


Assuntos
Canais de Cloreto/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Fluorescência Verde/genética , Proteínas Mitocondriais/genética , Tecido Adiposo Marrom/embriologia , Tecido Adiposo Marrom/crescimento & desenvolvimento , Tecido Adiposo Marrom/metabolismo , Animais , Encéfalo/embriologia , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Canais de Cloreto/metabolismo , Epiderme/embriologia , Epiderme/crescimento & desenvolvimento , Epiderme/metabolismo , Coração Fetal/embriologia , Coração Fetal/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Coração/crescimento & desenvolvimento , Immunoblotting , Imuno-Histoquímica , Hibridização In Situ , Rim/embriologia , Rim/crescimento & desenvolvimento , Rim/metabolismo , Fígado/embriologia , Fígado/crescimento & desenvolvimento , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Confocal , Proteínas Mitocondriais/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Timo/embriologia , Timo/crescimento & desenvolvimento , Timo/metabolismo
6.
Mol Carcinog ; 53(8): 610-24, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23401136

RESUMO

The KAI1/CD82 tetraspanin is a widely expressed cell surface molecule thought to organize diverse cellular signaling processes. KAI1/CD82 suppresses metastasis but not tumorigenicity, establishing it as one of a class of metastasis suppressor genes. In order to further assess its functions, we have characterized the phenotypic properties of Kai1/Cd82 deleted mice, including viability, fertility, lymphocyte composition, blood chemistry and tissue histopathology, and of their wild-type and heterozygote littermates. Interestingly, Kai1/Cd82(-/-) showed no obvious genotype associated defects in any of these processes and displayed no genotype associated histopathologic abnormalities after 12 or 18 months of life. Expression profiles of non-immortal, wild-type and Kai1/Cd82(-/-) mouse embryo fibroblast (MEFs) indicated distinct sex-specific and genotype-specific profiles. These data identify 191 and 1,271 differentially expressed transcripts (by twofold at P < 0.01) based on Kai1/CD82 genotype status in female and male MEFs, respectively. Differentially expressed genes in male MEFs were surprisingly enriched for cell division related processes, suggesting that Kai1/Cd82 may functionally affect these processes. This suggests that Kai/Cd82 has an unappreciated role in the early establishment of proliferation and division when challenged with a new environment that might play a role in adaptability to new metastatic sites.


Assuntos
Proliferação de Células , Embrião de Mamíferos/metabolismo , Fibroblastos/metabolismo , Proteína Kangai-1/fisiologia , Neoplasias Experimentais/mortalidade , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Northern Blotting , Western Blotting , Células Cultivadas , Embrião de Mamíferos/citologia , Feminino , Fibroblastos/citologia , Perfilação da Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias Experimentais/genética , Neoplasias Experimentais/patologia , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida
7.
PLoS One ; 19(3): e0288953, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38489327

RESUMO

In this study, we intensively measured the longitudinal productivity and survival of 362 commercially managed honey bee colonies in Canada, over a two-year period. A full factorial experimental design was used, whereby two treatments were repeated across apiaries situated in three distinct geographic regions: Northern Alberta, Southern Alberta and Prince Edward Island, each having unique bee management strategies. In the protein supplemented treatment, colonies were continuously provided a commercial protein supplement containing 25% w/w pollen, in addition to any feed normally provided by beekeepers in that region. In the fumagillin treatment, colonies were treated with the label dose of Fumagilin-B® each year during the fall. Neither treatment provided consistent benefits across all sites and dates. Fumagillin was associated with a large increase in honey production only at the Northern Alberta site, while protein supplementation produced an early season increase in brood production only at the Southern Alberta site. The protein supplement provided no long-lasting benefit at any site and was also associated with an increased risk of death and decreased colony size later in the study. Differences in colony survival and productivity among regions, and among colonies within beekeeping operations, were far larger than the effects of either treatment, suggesting that returns from extra feed supplements and fumagillin were highly contextually dependent. We conclude that use of fumagillin is safe and sometimes beneficial, but that beekeepers should only consider excess protein supplementation when natural forage is limiting.


Assuntos
Cicloexanos , Ácidos Graxos Insaturados , Mel , Abelhas , Animais , Estações do Ano , Suplementos Nutricionais , Alberta , Sesquiterpenos
8.
J Econ Entomol ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38877967

RESUMO

Highbush blueberry pollination depends on managed honey bees (Apis mellifera) L. for adequate fruit sets; however, beekeepers have raised concerns about the poor health of colonies after pollinating this crop. Postulated causes include agrochemical exposure, nutritional deficits, and interactions with parasites and pathogens, particularly Melisococcus plutonius [(ex. White) Bailey and Collins, Lactobacillales: Enterococcaceae], the causal agent of European foulbrood disease, but other pathogens could be involved. To broadly investigate common honey bee pathogens in relation to blueberry pollination, we sampled adult honey bees from colonies at time points corresponding to before (t1), during (t2), at the end (t3), and after (t4) highbush blueberry pollination in British Columbia, Canada, across 2 years (2020 and 2021). Nine viruses, as well as M. plutonius, Vairimorpha ceranae, and V. apis [Tokarev et al., Microsporidia: Nosematidae; formerly Nosema ceranae (Fries et al.) and N. apis (Zander)], were detected by PCR and compared among colonies located near and far from blueberry fields. We found a significant interactive effect of time and blueberry proximity on the multivariate pathogen community, mainly due to differences at t4 (corresponding to ~6 wk after the beginning of the pollination period). Post hoc comparisons of pathogens in near and far groups at t4 showed that detections of sacbrood virus (SBV), which was significantly higher in the near group, not M. plutonius, was the primary driver. Further research is needed to determine if the association of SBV with highbush blueberry pollination is contributing to the health decline that beekeepers observe after pollinating this crop.

9.
Curr Biol ; 34(9): 1893-1903.e3, 2024 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-38636513

RESUMO

Honey bees play a major role in crop pollination but have experienced declining health throughout most of the globe. Despite decades of research on key honey bee stressors (e.g., parasitic Varroa destructor mites and viruses), researchers cannot fully explain or predict colony mortality, potentially because it is caused by exposure to multiple interacting stressors in the field. Understanding which honey bee stressors co-occur and have the potential to interact is therefore of profound importance. Here, we used the emerging field of systems theory to characterize the stressor networks found in honey bee colonies after they were placed in fields containing economically valuable crops across Canada. Honey bee stressor networks were often highly complex, with hundreds of potential interactions between stressors. Their placement in crops for the pollination season generally exposed colonies to more complex stressor networks, with an average of 23 stressors and 307 interactions. We discovered that the most influential stressors in a network-those that substantively impacted network architecture-are not currently addressed by beekeepers. Finally, the stressor networks showed substantial divergence among crop systems from different regions, which is consistent with the knowledge that some crops (e.g., highbush blueberry) are traditionally riskier to honey bees than others. Our approach sheds light on the stressor networks that honey bees encounter in the field and underscores the importance of considering interactions among stressors. Clearly, addressing and managing these issues will require solutions that are tailored to specific crops and regions and their associated stressor networks.


Assuntos
Produtos Agrícolas , Polinização , Abelhas/fisiologia , Abelhas/parasitologia , Animais , Varroidae/fisiologia , Canadá , Estresse Fisiológico , Criação de Abelhas/métodos
10.
J Econ Entomol ; 116(3): 686-696, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37040616

RESUMO

Canadian beekeepers faced widespread levels of high honey bee colony mortality over the winter of 2021/2022, with an average winter loss of 45%. To understand the economic impact of winter colony mortality in Canada and the beekeeping management strategies used to mitigate these losses, we develop a profit model of commercial beekeeping operations in Alberta, Canada. Our model shows that for operations engaging in commercial pollination as well as honey production (compared to honey production alone), per colony profit is higher and operations are better able to withstand fluctuations in exogenous variables such as prices and environmental factors affecting productivity including winter mortality rates. The results also suggest that beekeeping operations that replace winter colony losses with splits instead of package bees accrue higher per colony profit than those importing packages to replace losses. Further, operations that produce their own queens to use in their replacement splits, accrue even higher profit. Our results demonstrate that the profitability of beekeeping operations is dependent on several factors including winter mortality rates, colony replacement strategies, and the diversification of revenue sources. Beekeepers who are not as susceptible to price and risk fluctuations in international markets and imported bee risks accrue more consistently positive profits.


Assuntos
Mel , Himenópteros , Abelhas , Animais , Alberta , Estações do Ano , Criação de Abelhas
11.
J Econ Entomol ; 116(3): 651-661, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37119539

RESUMO

Fumagilin-B is used to treat nosema infection in honey bee colonies; however, it is unclear whether treatment consistently reduces Vairimorpha ceranae (Fries et al.) abundance and improves colony strength and survival in the Canadian Prairies. This study assessed spring and fall fumagillin treatments on nosema abundance, colony strength, and mortality in 2 different beekeeping regions within Alberta, using both indoor and outdoor wintering management at each site. We compared 4 fumagillin treatments: Spring-only, Fall-only, Spring-and-Fall, and Control (no treatment). The spring treatment dose was ~68 mg/colony, whereas the fall treatment dose was 120 or 48 mg/colony, depending on the year. We found that the colonies were infected predominately with V. ceranae, with V. apis (Zander) present only in mixed infections in a subset of colonies. Although treatment in either the spring or fall did reduce nosema abundance in the short term, it did not eliminate the infection, making continued monitoring necessary. Colony strength was improved by spring treatment in some locations but not consistently, possibly due to the treatment timing or low dose. The combined spring and fall treatment increased colony survival over winter in one of 2 yr. Wintering method did not interact with treatment to affect nosema abundance in the spring. There does not appear to be a significant residual benefit of fall treatment as it did not reduce spring nosema abundance or increase colony population. Therefore, spring treatment should be applied to reduce spring V. ceranae abundance rather than relying on residual efficacy from previous fall treatments.


Assuntos
Himenópteros , Nosema , Abelhas , Animais , Canadá , Pradaria
12.
Biotechnol Adv ; 69: 108245, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37652144

RESUMO

Carbohydrates are chemically and structurally diverse biomolecules, serving numerous and varied roles in agricultural ecosystems. Crops and horticulture products are inherent sources of carbohydrates that are consumed by humans and non-human animals alike; however carbohydrates are also present in other agricultural materials, such as soil and compost, human and animal tissues, milk and dairy products, and honey. The biosynthesis, modification, and flow of carbohydrates within and between agricultural ecosystems is intimately related with microbial communities that colonize and thrive within these environments. Recent advances in -omics techniques have ushered in a new era for microbial ecology by illuminating the functional potential for carbohydrate metabolism encoded within microbial genomes, while agricultural glycomics is providing fresh perspective on carbohydrate-microbe interactions and how they influence the flow of functionalized carbon. Indeed, carbohydrates and carbohydrate-active enzymes are interventions with unrealized potential for improving carbon sequestration, soil fertility and stability, developing alternatives to antimicrobials, and circular production systems. In this manner, glycomics represents a new frontier for carbohydrate-based biotechnological solutions for agricultural systems facing escalating challenges, such as the changing climate.


Assuntos
Carboidratos , Microbiota , Animais , Carboidratos/química , Metabolismo dos Carboidratos , Agricultura , Solo/química
13.
Plant Methods ; 19(1): 120, 2023 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-37925401

RESUMO

BACKGROUND: The mutualistic interaction between entomophilous plants and pollinators is fundamental to the structure of most terrestrial ecosystems. The sensitive nature of this relationship has been disrupted by anthropogenic modifications to natural landscapes, warranting development of new methods for exploring this trophic interaction. Characterizing the composition of pollen collected by pollinators, e.g. Apis mellifera, is a common means of exploring this relationship, but traditional methods of microscopic pollen assessment are laborious and limited in their scope. The development of pollen metabarcoding as a method of rapidly characterizing the abundance and diversity of pollen within mixed samples presents a new frontier for this type of work, but metabarcoding may have limitations, and validation is warranted before any suite of primers can be confidently used in a research program. We set out to evaluate the utility of an integrative approach, using a set of established primers (ITS2 and rbcL) versus melissopalynological analysis for characterizing 27 mixed-pollen samples from agricultural sites across Canada. RESULTS: Both individual markers performed well relative to melissopalynology at the family level with decreases in the strength of correlation and linear model fits at the genus level. Integrating data from both markers together via a multi-locus approach provided the best rank-based correlation between metagenetic and melissopalynological data at both the genus (ρ = 0.659; p < 0.001) and family level (ρ = 0.830; p < 0.001). Species accumulation curves indicated that, after controlling for sampling effort, melissopalynological characterization provides similar or higher species richness estimates than either marker. The higher number of plant species discovered via the metabarcoding approach simply reflects the vastly greater sampling effort in comparison to melissopalynology. CONCLUSIONS: Pollen metabarcoding performed well at characterizing the composition of mixed pollen samples relative to a traditional melissopalynological approach. Limitations to the quantitative application of this method can be addressed by adopting a multi-locus approach that integrates information from multiple markers.

14.
J Proteome Res ; 11(3): 1561-70, 2012 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-22214408

RESUMO

Determination of disease-relevant proteomic profiles from limited tissue specimens, such as pathological biopsies and tissues from small model organisms, remains an analytical challenge and a much needed clinical goal. In this study, a transgenic mouse disease model of cardiac-specific H-Ras-G12V induced hypertrophic cardiomyopathy provided a system to explore the potential of using mass spectrometry (MS)-based proteomics to obtain a disease-relevant molecular profile from amount-limited specimens that are routinely used in pathological diagnosis. Our method employs a two-stage methanol-assisted solubilization to digest lysates prepared from 8-µm-thick fresh-frozen histological tissue sections of diseased/experimental and normal/control hearts. Coupling this approach with a nanoflow reversed-phase liquid chromatography (LC) and a hybrid linear ion trap/Fourier transform-ion cyclotron resonance MS resulted in the identification of 704 and 752 proteins in hypertrophic and wild-type (control) myocardium, respectively. The disease driving H-Ras protein along with vimentin were unambiguously identified by LC-MS in hypertrophic myocardium and cross-validated by immunohistochemistry and western blotting. The pathway analysis involving proteins identified by MS showed strong association of proteomic data with cardiovascular disease. More importantly, the MS identification and subsequent cross-validation of Wnt3a and ß-catenin, in conjunction with IHC identification of phosphorylated GSK-3ß and nuclear localization of ß-catenin, provided evidence of Wnt/ß-catenin canonical pathway activation secondary to Ras activation in the course of pathogenic myocardial hypertrophic transformation. Our method yields results indicating that the described proteomic approach permits molecular discovery and assessment of differentially expressed proteins regulating H-Ras induced hypertrophic cardiomyopathy. Selected proteins and pathways can be further investigated using immunohistochemical techniques applied to serial tissue sections of similar or different origin.


Assuntos
Cardiomiopatia Hipertrófica/metabolismo , Miocárdio/metabolismo , Proteoma/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Sequência de Aminoácidos , Animais , Cardiomiopatia Hipertrófica/genética , Cromatografia Líquida , Análise por Conglomerados , Expressão Gênica , Regulação da Expressão Gênica , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Fragmentos de Peptídeos/química , Precursores de Proteínas/química , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Proteoma/genética , Proteômica , Proteínas Proto-Oncogênicas p21(ras)/química , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Vimentina/metabolismo , Proteína Wnt3A/metabolismo , beta Catenina/metabolismo
15.
Ecol Lett ; 15(3): 227-34, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22221802

RESUMO

Environmental changes threaten plant-pollinator mutualisms and their critical ecosystem service. Drivers such as land use, invasions and climate change can affect pollinator diversity or species encounter rates. However, nitrogen deposition, climate warming and CO(2) enrichment could interact to disrupt this crucial mutualism by altering plant chemistry in ways that alter floral attractiveness or even nutritional rewards for pollinators. Using a pumpkin model system, we show that these drivers non-additively affect flower morphology, phenology, flower sex ratios and nectar chemistry (sugar and amino acids), thereby altering the attractiveness of nectar to bumble bee pollinators and reducing worker longevity. Alarmingly, bees were attracted to, and consumed more, nectar from a treatment that reduced their survival by 22%. Thus, three of the five major drivers of global environmental change have previously unknown interactive effects on plant-pollinator mutualisms that could not be predicted from studies of individual drivers in isolation.


Assuntos
Abelhas/fisiologia , Dióxido de Carbono , Ecossistema , Nitrogênio , Néctar de Plantas/química , Fenômenos Fisiológicos Vegetais , Polinização , Aminoácidos/análise , Animais , Cucurbita/fisiologia , Flores/química , Flores/crescimento & desenvolvimento , Flores/fisiologia , Aquecimento Global , Taxa de Sobrevida
16.
J Econ Entomol ; 115(2): 417-429, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35181788

RESUMO

Adequate nutrition is required to support productive honey bee colonies, therefore beekeepers supplement colonies with additional protein at targeted time points. We tested the effects of commercially available protein feeds in spring, in advance of colonies being used for hybrid canola pollination. The feed treatments across the three-year study included the following patty types: Global 15% pollen, Global 0% pollen, Bee Pollen-Ate, FeedBee, and Healthy Bees, as well as an unsupplemented control in year two of the study only. The amount of feed consumed varied among colonies, treatments, date, and year. Similarly, there were also differences in feed efficiency (bees reared per gram of feed consumed), likely due to the relative availability of external forage sources to supplement the feed provided. Unsupplemented colonies were able to rear less brood, and subsequently had fewer adult bees than supplemented colonies, in an apiary where pollen was not abundant. Differences in consumption among treatments often failed to translate in to differences in amount of brood reared or subsequent adult population. All the protein feed treatments contained all ten amino acids essential to honey bees, however lysine and arginine were below the optimal proportion required for growth in all patties except the FeedBee patty. The amount of protein and amount and types of sugars and fats in the products also varied among product type and batch. The results of this study demonstrate a benefit to supplementary spring protein feeding to increase honey bee colony populations in advance of a summer pollination market.


Assuntos
Brassica napus , Himenópteros , Animais , Abelhas , Pólen , Polinização , Estações do Ano
17.
Front Public Health ; 10: 953198, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36211696

RESUMO

Objectives: To explore the effectiveness of a COVID-19 specific social vulnerability index, we examined the relative importance of four COVID-19 specific themes and three general themes of the COVID-19 Community Vulnerability Index (CCVI) in explaining COVID-19 mortality rates in Cook County, Illinois. Methods: We counted COVID-19 death records from the Cook County Medical Examiner's Office, geocoded incident addresses by census tracts, and appended census tracts' CCVI scores. Negative binomial regression and Random Forest were used to examine the relative importance of CCVI themes in explaining COVID-19 mortality rates. Results: COVID-19 specific Themes 6 (High risk environments) and 4 (Epidemiological factors) were the most important in explaining COVID-19 mortality (incidence rate ratio (IRR) = 6.80 and 6.44, respectively), followed by a general Theme 2 (Minority status & language, IRR = 3.26). Conclusion: The addition of disaster-specific indicators may improve the accuracy of social vulnerability indices. However, variance for Theme 6 was entirely from the long-term care resident indicator, as the other two indicators were constant at the census tract level. Thus, CCVI should be further refined to improve its effectiveness in identifying vulnerable communities. Also, building a more robust local data infrastructure is critical to understanding the vulnerabilities of local places.


Assuntos
COVID-19 , COVID-19/epidemiologia , Humanos , Incidência , Grupos Minoritários
18.
PLoS One ; 17(1): e0263273, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35100308

RESUMO

Many pathogens and parasites have evolved to overwhelm and suppress their host's immune system. Nevertheless, the interactive effects of these agents on colony productivity and wintering success have been relatively unexplored, particularly in large-scale phenomic studies. As a defense mechanism, honey bees have evolved remarkable social behaviors to defend against pathogen and parasite challenges, which reduce the impact of disease and improve colony health. To investigate the complex role of pathogens, parasites and social immunity behaviors in relation to colony productivity and outcomes, we extensively studied colonies at several locations across Canada for two years. In 2016 and 2017, colonies founded with 1-year-old queens of diverse genetic origin were evaluated, which represented a generalized subset of the Canadian bee population. During each experimental year (May through April), we collected phenotypic data and sampled colonies for pathogen analysis in a standardized manner. Measures included: colony size and productivity (colony weight, cluster size, honey production, and sealed brood population), social immunity traits (hygienic behavior, instantaneous mite population growth rate, and grooming behavior), as well as quantification of gut parasites (Nosema spp., and Lotmaria passim), viruses (DWV-A, DWV-B, BQCV and SBV) and external parasites (Varroa destructor). Our goal was to examine: 1) correlations between pathogens and colony phenotypes; 2) the dynamics of pathogens and parasites on colony phenotypes and productivity traits; and 3) the effects of social immunity behaviors on colony pathogen load. Our results show that colonies expressing high levels of some social immunity behaviors were associated with low levels of pathogens/parasites, including viruses, Nosema spp., and V. destructor. In addition, we determined that elevated viral and Nosema spp. levels were associated with low levels of colony productivity, and that five out of six pathogenic factors measured were negatively associated with colony size and weight in both fall and spring periods. Finally, this study also provides information about the incidence and abundance of pathogens, colony phenotypes, and further disentangles their inter-correlation, so as to better understand drivers of honey bee colony health and productivity.


Assuntos
Abelhas/parasitologia , Abelhas/virologia , Comportamento Animal/fisiologia , Saúde , Interações Hospedeiro-Patógeno , Fenômica , Animais , Canadá , Geografia , Mel , Modelos Lineares , Parasitos , Fenótipo , Tamanho da Amostra , Estações do Ano , Comportamento Social , Varroidae
19.
Oncoimmunology ; 11(1): 2010905, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35481284

RESUMO

Current immunotherapies for lung cancer are only effective in a subset of patients. Identifying tumor-derived factors that facilitate immunosuppression offers the opportunity to develop novel strategies to supplement and improve current therapeutics. We sought to determine whether expression of driver oncogenes in lung cancer cells affects cytokine secretion, alters the local immune environment, and influences lung tumor progression. We demonstrate that oncogenic EGFR and KRAS mutations, which are early events in lung tumourigenesis, can drive cytokine and chemokine production by cancer cells. One of the most prominent changes was in CCL5, which was rapidly induced by KRASG12V or EGFRL858R expression, through MAPK activation. Immunocompetent mice implanted with syngeneic KRAS-mutant lung cancer cells deficient in CCL5 have decreased regulatory T cells (Tregs), evidence of T cell exhaustion, and reduced lung tumor burden, indicating tumor-cell CCL5 production contributes to an immune suppressive environment in the lungs. Furthermore, high CCL5 expression correlates with poor prognosis, immunosuppressive regulatory T cells, and alteration to CD8 effector function in lung adenocarcinoma patients. Our data support targeting CCL5 or CCL5 receptors on immune suppressive cells to prevent formation of an immune suppressive tumor microenvironment that promotes lung cancer progression and immunotherapy insensitivity.


Assuntos
Neoplasias Pulmonares , Proteínas Proto-Oncogênicas p21(ras) , Animais , Quimiocina CCL5/genética , Quimiocina CCL5/metabolismo , Citocinas/metabolismo , Receptores ErbB/metabolismo , Humanos , Pulmão/metabolismo , Pulmão/patologia , Neoplasias Pulmonares/genética , Camundongos , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Microambiente Tumoral
20.
PLoS One ; 16(10): e0258801, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34695141

RESUMO

The epidemiology of Nosema spp. in honey bees, Apis mellifera, may be affected by winter conditions as cold temperatures and differing wintering methods (indoor and outdoor) provide varying levels of temperature stress and defecation flight opportunities. Across the Canadian Prairies, including Alberta, the length and severity of winter vary among geographic locations. This study investigates the seasonal pattern of Nosema abundance in two Alberta locations using indoor and outdoor wintering methods and its impact on bee population, survival, and commercial viability. This study found that N. ceranae had a distinct seasonal pattern in Alberta, with high spore abundance in spring, declining to low levels in the summer and fall. The results showed that fall Nosema monitoring might not be the best indicator of treatment needs or future colony health outcomes. There was no clear pattern for differences in N. ceranae abundance by location or wintering method. However, wintering method affected survival with colonies wintered indoors having lower mortality and more rapid spring population build-up than outdoor-wintered colonies. The results suggest that the existing Nosema threshold should be reinvestigated with wintering method in mind to provide more favorable outcomes for beekeepers. Average Nosema abundance in the spring was a significant predictor of end-of-study winter colony mortality, highlighting the importance of spring Nosema monitoring and treatments.


Assuntos
Criação de Abelhas/métodos , Abelhas/crescimento & desenvolvimento , Micoses/epidemiologia , Nosema/patogenicidade , Estações do Ano , Temperatura , Alberta/epidemiologia , Animais , Abelhas/microbiologia , Micoses/microbiologia , Nosema/isolamento & purificação
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