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1.
J Vasc Surg ; 80(1): 279-287, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38215952

RESUMO

OBJECTIVE: Restenosis and late occlusion remain a significant problem for endovascular treatment of peripheral artery disease. This meta-analysis aims to evaluate the effect of cilostazol on late outcomes after endovascular repair of occlusive femoropopliteal disease. METHODS: A systematic literature review was conducted conforming to established criteria to identify articles published up to September 2023 evaluating late outcomes after endovascular treatment for atherosclerotic femoropopliteal disease. Eligible studies should compare outcomes between patients treated with cilostazol and patients not treated with cilostazol. Both prospective and retrospective studies were eligible. Late outcomes included primary patency (PP), restenosis, target lesion revascularization (TLR), and major amputation during follow-up. RESULTS: Overall, 10 clinical studies were identified for analysis including 4721 patients (1831 with cilostazol vs 2890 without cilostazol) that were treated for 5703 lesions (2235 with cilostazol vs 3468 without cilostazol). All studies were performed in Japan. Mean follow-up was 24.1 ± 12.5 months. Cilostazol was associated with a lower risk for restenosis (pooled odds ratio [OR], 0.503; 95% confidence interval [CI], 0.383-0.660; P < .0001). However, no association was found between cilostazol and TLR (pooled OR, 0.918; 95% CI, 0.300-2.812; P = .881) as well as major amputation (pooled OR, 1.512; 95% CI, 0.734-3.116; P = .263). Regarding primary patency, cilostazol was associated with a higher 12-month PP (OR, 3.047; 95% CI, 1.168-7.946; P = .023), and a higher 36-month PP (OR, 1.616; 95% CI, 1.412-1.850; P < .0001). No association was found between cilostazol and mortality during follow-up (pooled OR, .755; 95% CI, 0.293-1.946; P = .561). CONCLUSIONS: Cilostazol seems to have a positive effect on 1- to 3-year PP and restenosis rates among patients treated endovascularly for atherosclerotic femoropopliteal disease. A positive effect on TLR and amputation risk was not verified in this review.


Assuntos
Cilostazol , Procedimentos Endovasculares , Artéria Femoral , Doença Arterial Periférica , Artéria Poplítea , Grau de Desobstrução Vascular , Humanos , Cilostazol/uso terapêutico , Cilostazol/efeitos adversos , Doença Arterial Periférica/fisiopatologia , Doença Arterial Periférica/terapia , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/diagnóstico por imagem , Procedimentos Endovasculares/efeitos adversos , Artéria Femoral/fisiopatologia , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/cirurgia , Artéria Poplítea/fisiopatologia , Artéria Poplítea/diagnóstico por imagem , Grau de Desobstrução Vascular/efeitos dos fármacos , Resultado do Tratamento , Fatores de Tempo , Fatores de Risco , Salvamento de Membro , Amputação Cirúrgica , Recidiva , Feminino , Masculino , Medição de Risco , Idoso
2.
J Surg Case Rep ; 2023(10): rjad589, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37901608

RESUMO

Ureteral hernias are an uncommon entity that are usually incidentally discovered during inguinal hernia repair. However, when symptomatic, they could cause severe symptoms from the urinary system and even affect renal function. We aim to report a rare case of a 91-year-old male patient with urosepsis because of ureteral entrapment within an inguinal hernia, and further discuss proper management of such cases.

3.
Adv Exp Med Biol ; 1425: 217-227, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37581796

RESUMO

To investigate the phenomenon of moral harassment (mobbing) as well as the effect of demographic and occupational characteristics of healthcare professionals working in a public provincial general hospital and a private hospital in Athens a cross-sectional survey was designed. The study was conducted from November to December 2021 through the application of the Leymann Inventory of Psychological Terror (LIPT) a widely recognized research tool for the quantitative investigation of ethical harassment in the workplace. 264 fully completed questionnaires were collected out of the 300 that were distributed in both hospitals (response rates: 92% for the public hospital and 83.3% for the private). It was observed that private hospital's employees were morally harassed to a greater extent and for a longer time than the employees of a public hospital. The levels of moral harassment were quite high, indicating the necessity of thorough audit by the management in both hospitals.


Assuntos
Bullying , Condições de Trabalho , Humanos , Estudos Transversais , Grécia/epidemiologia , Incidência , Hospitais Privados , Inquéritos e Questionários
4.
Adv Exp Med Biol ; 1425: 331-343, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37581807

RESUMO

To investigate interdisciplinary cooperation and communication among doctors and nurses along with its role in improving the quality of their professional life, a cross-sectional survey was designed. The study was carried out from February to April 2021 through the application of an anonymous, structured, self-completed, closed-ended questionnaire in a convenience sample consisting of 110 healthcare professionals currently working in the intensive care units (ICUs) of three distinct hospitals (response rate: 76.4%). It was observed that medical personnel manifested a more positive stance toward interdisciplinary collaboration than nursing while women seemed to believe more than men that nurses' administrative skills are not valued enough by doctors. Nurses with limited work experience reported that doctors show scarce respect to nurses in the presence of patients' parents and companions while male nurses acknowledged more the provision of multidimensional care given to patients. Occupational stress, professional satisfaction, and burnout levels were mainly moderate across study participants.


Assuntos
Esgotamento Profissional , COVID-19 , Enfermeiras e Enfermeiros , Humanos , Masculino , Feminino , Melhoria de Qualidade , Estudos Transversais , Pandemias , COVID-19/epidemiologia , Unidades de Terapia Intensiva , Esgotamento Profissional/epidemiologia , Comunicação , Inquéritos e Questionários , Satisfação no Emprego
5.
Adv Exp Med Biol ; 1425: 345-352, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37581808

RESUMO

To investigate job satisfaction and burnout levels among the personnel of a public oncology hospital amid the COVID-19 pandemic, a cross-sectional survey was designed. The study was carried out from December 2021 to January 2022 through the application of an anonymous, structured, self-completed, closed-ended questionnaire, consisting of the Job Satisfaction Survey (JSS) and the Copenhagen Burnout Inventory (CBI) in a convenience sample comprised by 117 employees of "Agioi Anargyroi" General Oncology Hospital (response rate: 98%). It was observed that while overall job satisfaction was reduced, several of its determining dimensions like supervision, relationship with co-workers, or work nature were increased. Also, an average overall burnout of 49% was observed across all participants, with women, nurses, and those with a lower educational level experiencing it more intensely. The COVID-19 pandemic outbreak affected negatively healthcare professionals who experienced significant personal and occupational burnout, consequently reducing their job satisfaction.


Assuntos
Esgotamento Profissional , COVID-19 , Humanos , Feminino , Esgotamento Profissional/epidemiologia , Satisfação no Emprego , Estudos Transversais , Pandemias , COVID-19/epidemiologia , Esgotamento Psicológico , Recursos Humanos , Inquéritos e Questionários , Hospitais
6.
Adv Exp Med Biol ; 1425: 645-662, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37581838

RESUMO

INTRODUCTION: Smoking has a harmful effect on human body and is rated to be the primary cause of preventable premature disease and death worldwide, while it is responsible for at least 25 life-threatening diseases. METHODS: An empirical investigation has been carried out through the development and distribution of a structured questionnaire. The sample of empirical investigation consisted of 150 smokers aged over 18 years (response rate 85.7%). ANALYSIS: Descriptive analysis and correlation control of questionnaire variables are used to report the findings of the study. RESULTS: Information about passive smoking, smoking consequences, and current therapies in quitting smoking were rated highest among smoke-related information needs. The main sources of information were family/relatives/friends/colleagues and Internet and less important factors were formal sources like medical staff, health professionals, and primary health care services. Ε-health literacy is correlated with higher self-efficacy, positive intention to quit smoking, and better educational level while is negatively correlated with increasing age. CONCLUSIONS: The creation of specialized programs and upgraded information services is fundamental for successful smoking cessation. These programs and services should be addressed to all socioeconomic groups and combined with the improvement in smokers' e-health literacy will contribute to a higher self-efficacy and finally drive them to quit smoking.


Assuntos
Abandono do Hábito de Fumar , Humanos , Adulto , Pessoa de Meia-Idade , Fumantes , Comportamento de Busca de Informação , Intenção , Inquéritos e Questionários
7.
Ecol Evol ; 13(7): e10289, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37435028

RESUMO

Mason bees (Osmia spp.) are efficient fruit tree pollinators that can be encouraged to occupy and breed in artificial nesting material. In sweet cherry orchards, they are occasionally used as an alternative managed pollinator as a replacement for or in addition to honey bees (Apis mellifera). Yet, the lack of practical guidelines on management practices, for example optimal stocking rates, for both mason bee nesting material and honey bees might compromise pollination service provision. In this study, we assessed the relationship between stocking rates (honey bee hives and mason bee nesting material) and the abundance of honey bees and mason bees in 17 sweet cherry (Prunus avium) orchards in Central Germany. We furthermore performed a pollination experiment to explore the interactive effect of mason bees and honey bees on sweet cherry fruit set. In the orchards, both honey bee and mason bee abundance increased with increasing stocking rates of hives or nesting material, respectively. Honey bee abundance increased linearly with stocking rates. In contrast, mason bee abundance asymptoted at 2-3 nesting boxes per ha, beyond which more boxes resulted in little increase in visitation rate. Our pollination experiment demonstrated that orchards were pollen limited, with only 28% of insect-pollinated flowers setting fruit versus 39% of optimally hand-pollinated flowers. Honey bees and mason bees enhanced sweet cherry fruit set, but only when both were present and not when either was present alone in an orchard. Our findings demonstrate that offering nesting material for mason bees and employing honey bee hives can enhance bee abundance in sweet cherry orchards. By increasing honey bee abundance in combination with enhanced mason bee abundance, farmers can substantially boost fruit set and potentially sweet cherry yield. To enhance pollination services, farmers should consider the benefits of increasing pollinator biodiversity as an immediate benefit to improve crop yields.

8.
Ecol Lett ; 26(9): 1629-1642, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37345567

RESUMO

Urbanization is increasing worldwide, with major impacts on biodiversity, species interactions and ecosystem functioning. Pollination is an ecosystem function vital for terrestrial ecosystems and food security; however, the processes underlying the patterns of pollinator diversity and the ecosystem services they provide in cities have seldom been quantified. Here, we perform a comprehensive meta-analysis of 133 studies examining the effects of urbanization on pollinators and pollination. Our results confirm the widespread negative impacts of urbanization on pollinator richness and abundance, with Lepidoptera being the most affected group. Furthermore, pollinator responses were found to be trait-specific, with below-ground nesting and solitary Hymenoptera, and spring flyers more severely affected by urbanization. Meanwhile, cities promote non-native pollinators, which may exacerbate conservation risks to native species. Surprisingly, despite the negative effects of urbanization on pollinator diversity, pollination service measured as seed set is enhanced in non-tropical cities likely due to abundant generalists and managed pollinators therein. We emphasize that the richness of local flowering plants could mitigate the negative impacts of urbanization on pollinator diversity. Overall, the results demonstrate the varying magnitudes of multiple moderators on urban pollinators and pollination services and could help guide conservation actions for biodiversity and ecosystem function for a sustainable future.


Assuntos
Ecossistema , Urbanização , Abelhas , Polinização/fisiologia , Biodiversidade , Cidades , Flores
9.
Mol Phylogenet Evol ; 186: 107839, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37290582

RESUMO

Pollination and seed dispersal of plants by animals are key mutualistic processes for the conservation of plant diversity and ecosystem functioning. Although different animals frequently act as pollinators or seed dispersers, some species can provide both functions, so-called 'double mutualists', suggesting that the evolution of pollination and seed dispersal may be linked. Here, we assess the macroevolution of mutualistic behaviours in lizards (Lacertilia) by applying comparative methods to a phylogeny comprising 2,838 species. We found that both flower visitation (potential pollination; recorded in 64 species [2.3% of total] across 9 families) and seed dispersal (recorded in 382 species [13,5% of total] across 26 families) have evolved repeatedly in Lacertilia. Furthermore, we found that seed dispersal activity pre-dated flower visitation and that the evolution of seed dispersal activity and flower visitation was correlated, illustrating a potential evolutionary mechanism behind the emergence of double mutualisms. Finally, we provide evidence that lineages with flower visitation or seed dispersal activity have higher diversification rates than lineages lacking these behaviours. Our study illustrates the repeated innovation of (double) mutualisms across Lacertilia and we argue that island settings may provide the ecological conditions under which (double) mutualisms persist over macroevolutionary timescales.


Assuntos
Lagartos , Dispersão de Sementes , Animais , Ecossistema , Lagartos/genética , Filogenia , Plantas , Sementes , Polinização , Simbiose/genética
10.
Sci Rep ; 13(1): 2702, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36792660

RESUMO

Insect-provided pollination services are increasingly threatened due to alarming declines in insect pollinator populations. One of the main threats to insect pollinators and consequently pollination is urbanisation. Here, we investigate the effects of local habitat quality (patch size, flowering plant richness, bare soil cover, vegetation structure), degree of urbanisation (impervious surfaces) and 3D connectivity on bee, hoverfly and butterfly flower visitors and plant-flower visitor networks in flower-rich urban dry grasslands. Overall, the degree of urbanisation and the quality of the local habitat influenced the flowering plant and pollinator communities. Although flowering plant abundance increased with urbanisation, bee species richness and butterfly species richness decreased with increasing impervious surfaces. Flowering plant richness and ground nesting resource availability were positively related to bee richness and local vegetation structure boosted hoverfly and butterfly visitation rates. In terms of plant-pollinator interactions, insect pollinators visited a lower proportion of the available flowering plants in more urbanised areas and network modularity and specialisation increased with patch size. Our findings show that urban dry grasslands are valuable habitats for species-rich pollinator communities and further highlight the importance of minimizing the intensity of urbanisation and the potential of local management practices to support insect biodiversity in cities.


Assuntos
Borboletas , Magnoliopsida , Abelhas , Animais , Urbanização , Pradaria , Insetos , Ecossistema , Flores , Polinização
11.
BMC Ecol Evol ; 22(1): 94, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35918637

RESUMO

To accommodate an ever-increasing human population, agriculture is rapidly intensifying at the expense of natural habitat, with negative and widely reported effects on biodiversity in general and on wild bee abundance and diversity in particular. Cities are similarly increasing in area, though the impact of urbanisation on wild bees is more equivocal and potentially positive in northern temperate regions. Yet agriculture and urbanisation both lead to the loss and alteration of natural habitat, its fragmentation, a potential reduction in floral availability, and warmer temperatures, factors thought to be drivers of wild bee decline. They have also been shown to be factors to which wild bee populations respond through morphological change. Body size is one such trait that, because of its relation to individual fitness, has received growing attention as a morphological feature that responds to human induced modification in land use. Here, we investigated the change in body size of two sympatric orchid bee species on the Yucatan Peninsula of Mexico in response to urbanization and agricultural intensification. By measuring 540 male individuals sampled from overall 24 sites, we found that Euglossa dilemma and Euglossa viridissima were on average smaller in urban and agricultural habitats than in natural ones. We discuss the potential role of reduced availability of resources in driving the observed body size shifts. Agricultural and urban land management in tropical regions might benefit wild bees if it encompassed the planting of flowering herbs and trees to enhance their conservation.


Assuntos
Efeitos Antropogênicos , Biodiversidade , Animais , Abelhas , Tamanho Corporal , Ecossistema , Humanos , Urbanização
12.
J Anim Ecol ; 91(10): 2135-2148, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36002939

RESUMO

Urbanization is a global phenomenon that can affect fitness and could challenge the persistence of most species, including wild bee pollinators. Yet, how and which environmental features affect bee health and fitness within the urban ecosystem remain unclear. Here, we placed experimental Bombus terrestris colonies in sites spanning from the edge into a city's core to investigate bumble bee parasitism, foraging behaviour, energetic stress, colony growth and reproductive output. In each site, ambient temperature was recorded, the availability of floral resources was evaluated and landscape heterogeneity was characterized using land-cover maps. We found that Bombus terrestris parasitism levels increased across the season in line with colony growth but were negatively related to the proportion of impervious surfaces surrounding a site. Bombus terrestris foraging trip duration decreased with increasing ecotones (edge density) but, conversely, increased in sites with honey bee hives present. Energetic stress was evaluated as lowered trehalose titre in the haemolymph of returning foragers; stress increased with the proportion of impervious surfaces. Furthermore, our analyses identified ambient temperature to be a strong predictor of Bombus terrestris colony performance in that high ambient temperature reduced colony growth and indirectly the production of sexual offspring (gynes). Our results highlight the importance of ecotones as well as minimizing the intensity of urbanization and urban honey bee beekeeping for bumble bee colony health and foraging behaviour. They also point to the importance of microclimate (i.e. temperature) for bumble bee colony performance and suggest that increasing temperatures could have a negative impact in slowing colony weight gain, and indirectly in reducing colony reproduction.


Assuntos
Ecossistema , Trealose , Animais , Abelhas , Reprodução , Estações do Ano
13.
Cureus ; 14(6): e26344, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35903570

RESUMO

INTRODUCTION: Fatigue is associated with various diseases of different origins extending from immune disorders to cancer. The purpose of this study was to explore the psychometric properties/dimensionality of the Multidimensional Fatigue Inventory (MFI-20) questionnaire in samples of healthy adults and patient subgroups in Greece. METHODS: This was a multicenter cross-sectional study that included 80 women with breast cancer, 108 patients with multiple sclerosis (MS), 100 people with thalassemia diagnosis, and 185 healthy adults, aged 18-45 years. All patients were adults. Patients were recruited from a breast surgery clinic, a neurological clinic, and a thalassemia unit, while healthy adults were recruited from the University of West Attica students and personnel. The MFI-20, the modified fatigue impact scale (MFIS), the fatigue severity scale (FSS), and the Hamilton anxiety-depression scale (HANDS) were used. Internal consistency, repeatability, test-retest reliability, construct, and convergent validity were investigated. RESULTS: MFI-20 exhibited excellent reliability properties (internal consistency: Cronbach's alpha MFI-20 subscales ranged from 0.83 to 0.94; repeatability: Pearson's r = 0.335 [p < 0.001]). Significant correlations were found between MFI-20 and MFIS: Pearson's r = 0.870, FSS: Pearson's r = 0.582 - 0.335, and HANDS: Pearson's r = 0.734 - 0.442 (all p-values < 0.0001) on all subsamples. However, its dimensionality is questionable depending on the subpopulation tested, and the one-dimension perspective is possible. MS patients exhibited the highest total score (55.26 ± 16.53), while thalassemia patients exhibited the lowest score (45.09 ± 13.54). In all subscales, thalassemia patients differed statistically significantly from the MS patients (p < 0.01), while in the reduced activity subscale, thalassemia patients differed significantly from all other groups (p < 0.01). CONCLUSIONS: As strict fatigue subscale classification is questionable, the use of MFI-20 total score is suggested for the assessment of fatigue in clinical populations. As MFI-20 is a very useful research tool for studying fatigue, the use of the total and/or partial scores depends on the clinical population. Total score instead of (or additionally) partial scores is suggested in clinical practice.

14.
Curr Opin Insect Sci ; 52: 100922, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35490874

RESUMO

Cities are expanding worldwide and urbanisation is considered a global threat to biodiversity. Urban ecology has provided important insights on how urban environmental changes might affect individuals, populations, and species; however, we know little about how the ecological impacts of urbanisation alter species interactions. Species interactions are the backbone of ecological communities and play a crucial role in population and community dynamics and in the generation, maintenance and structure of biodiversity. Here, I review urban ecological studies to identify key mechanistic pathways through which urban environmental processes could alter antagonistic and mutualistic interactions among species. More specifically, I focus on insect predation, parasitoidism and herbivory, competition, insect host-pathogen interactions, and pollination. I furthermore identify important knowledge gaps that require additional research attention and I suggest future research directions that may help to shed light on the mechanisms that affect species interactions and structure insect communities and will thus aid conservation management in cities.


Assuntos
Biodiversidade , Urbanização , Animais , Cidades , Insetos , Polinização
15.
Sci Adv ; 7(44): eabj1398, 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34714677

RESUMO

Social distancing in response to infectious diseases is a strategy exhibited by human and nonhuman animals to counteract the spread of pathogens and/or parasites. Honey bee (Apis mellifera) colonies are ideal models to study this behavior because of the compartmentalized structure of these societies, evolved under exposure to parasite pressure and the need to ensure efficient functioning. Here, by using a combination of spatial and behavioral approaches, we investigated whether the presence of the ectoparasite mite Varroa destructor induces changes in the social organization of A. mellifera colonies that could reduce the spread of the parasite. Our results demonstrated that honey bees react to the intrusion of V. destructor by modifying space use and social interactions to increase the social distancing between young (nurses) and old (foragers) cohorts of bees. These findings strongly suggest a behavioral strategy not previously reported in honey bees to limit the intracolony parasite transmission.

16.
Ecol Evol ; 11(20): 13723-13743, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34707813

RESUMO

Population genetics is a field of research that predates the current generations of sequencing technology. Those approaches, that were established before massively parallel sequencing methods, have been adapted to these new marker systems (in some cases involving the development of new methods) that allow genome-wide estimates of the four major micro-evolutionary forces-mutation, gene flow, genetic drift, and selection. Nevertheless, classic population genetic markers are still commonly used and a plethora of analysis methods and programs is available for these and high-throughput sequencing (HTS) data. These methods employ various and diverse theoretical and statistical frameworks, to varying degrees of success, to estimate similar evolutionary parameters making it difficult to get a concise overview across the available approaches. Presently, reviews on this topic generally focus on a particular class of methods to estimate one or two evolutionary parameters. Here, we provide a brief history of methods and a comprehensive list of available programs for estimating micro-evolutionary forces. We furthermore analyzed their usage within the research community based on popularity (citation bias) and discuss the implications of this bias for the software community. We found that a few programs received the majority of citations, with program success being independent of both the parameters estimated and the computing platform. The only deviation from a model of exponential growth in the number of citations was found for the presence of a graphical user interface (GUI). Interestingly, no relationship was found for the impact factor of the journals, when the tools were published, suggesting accessibility might be more important than visibility.

17.
Evol Appl ; 14(1): 53-68, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33519956

RESUMO

Urbanization is a global phenomenon with major effects on species, the structure of community functional traits and ecological interactions. Body size is a key species trait linked to metabolism, life-history and dispersal as well as a major determinant of ecological networks. Here, using a well-replicated urban-rural sampling design in Central Europe, we investigate the direction of change of body size in response to urbanization in three common bumblebee species, Bombus lapidarius, Bombus pascuorum and Bombus terrestris, and potential knock-on effects on pollination service provision. We found foragers of B. terrestris to be larger in cities and the body size of all species to be positively correlated with road density (albeit at different, species-specific scales); these are expected consequences of habitat fragmentation resulting from urbanization. High ambient temperature at sampling was associated with both a small body size and an increase in variation of body size in all three species. At the community level, the community-weighted mean body size and its variation increased with urbanization. Urbanization had an indirect positive effect on pollination services through its effects not only on flower visitation rate but also on community-weighted mean body size and its variation. We discuss the eco-evolutionary implications of the effect of urbanization on body size, and the relevance of these findings for the key ecosystem service of pollination.

18.
Sci Rep ; 10(1): 21756, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33303909

RESUMO

Bees and flowering plants are two closely interacting groups of organisms. Habitat loss and fragmentation associated with urbanisation are major threats to both partners. Yet how and why bee and floral richness and diversity co-vary within the urban landscape remain unclear. Here, we sampled bees and flowering plants in urban green spaces to investigate how bee and flowering plant species richness, their phylogenetic diversity and pollination-relevant functional trait diversity influence each other in response to urban fragmentation. As expected, bee abundance and richness were positively related to flowering plant richness, with bee body size (but not bee richness and diversity) increasing with nectar-holder depth of flowering plants. Causal modelling indicated that bottom-up effects dictated patterns of bee-flower relationships, with urban fragmentation diminishing flowering plants richness and thereby indirectly reducing bee species richness and abundance. The close relationship between bees and flowering plants highlights the risks of their parallel declines in response to land-use change within the urban landscape.


Assuntos
Abelhas/fisiologia , Biodiversidade , Planejamento de Cidades , Ecossistema , Magnoliopsida/genética , Magnoliopsida/fisiologia , Fenômenos Fisiológicos Vegetais , Urbanização , Animais , Abelhas/genética , Filogenia , Polinização , Risco
19.
Oecologia ; 194(3): 333-344, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32712873

RESUMO

Land-use alteration and climate seasonality have profound effects on bee species diversity by influencing the availability of nesting and floral resources. Here, using twelve sites embedded in an agriculture-forest mosaic in the tropical highlands of Guatemala, we investigated the relative effects of climate seasonality and landscape heterogeneity on bee and floral-resource community structure and on their mutualistic network architecture. We found that climate seasonality affected bee diversity, which was higher in the wet season and associated positively with the availability of floral resources across both seasons. Bee community composition also differed between seasons and it was mainly driven by floral-resource richness and the proportion of agricultural, semi-natural and forest cover. In addition to the effects on bee diversity, climate seasonality also affected flower-bee visitation networks. We documented higher relative (null model corrected) nestedness in the dry season compared to the wet season. Niche partitioning as a result of competition for scarce resources in the dry season could be the process driving the differences in the network structure between seasons. Furthermore, relative nestedness was consistently smaller than zero, and relative modularity and specialization were consistently larger than zero in both seasons, suggesting the existence of isolated groups of interacting partners in all our flower-bee visitation networks. Our results highlight the effect of climatic seasonality and the importance of preserving local floral resources and natural heterogeneous habitats for the conservation of bee communities and their pollination services in tropical highlands.


Assuntos
Ecossistema , Polinização , Agricultura , Animais , Abelhas , Flores , Estações do Ano
20.
Insects ; 11(2)2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32075232

RESUMO

Nosema ceranae is a widespread obligate intracellular parasite of the ventriculus of many species of honey bee (Apis), including the Western honey bee Apis mellifera, in which it may lead to colony death. It can be controlled in A. mellifera by feeding the antibiotic fumagillin to a colony, though this product is toxic to humans and its use has now been banned in many countries, so in beekeeping, there exists a need for alternative and safe products effective against N. ceranae. Honeybees produce propolis from resinous substances collected from plants and use it to protect their nest from parasites and pathogens; propolis is thought to decrease the microbial load of the hive. We hypothesized that propolis might also reduce N. ceranae infection of individual bees and that they might consume propolis as a form of self-medication. To test these hypotheses, we evaluated the effects of an ethanolic extract of propolis administered orally on the longevity and spore load of experimentally N. ceranae-infected worker bees and also tested whether infected bees were more attracted to, and consumed a greater proportion of, a diet containing propolis in comparison to uninfected bees. Propolis extracts and ethanol (solvent control) increased the lifespan of N. ceranae-infected bees, but only propolis extract significantly reduced spore load. Our propolis extract primarily contained derivatives of caffeic acid, ferulic acid, ellagic acid and quercetin. Choice, scan sampling and food consumption tests did not reveal any preference of N. ceranae-infected bees for commercial candy containing propolis. Our research supports the hypothesis that propolis represents an effective and safe product to control N. ceranae but worker bees seem not to use it to self-medicate when infected with this pathogen.

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