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1.
Behav Ecol ; 35(5): arae054, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39034972

RESUMO

Despite Batesian mimicry often eliciting predator avoidance, many Batesian mimics, such as some species of hoverfly (Syrphidae), are considered to have an "imperfect" resemblance to their model. One possible explanation for the persistence of apparently imperfect mimicry is that human perceptions of mimicry are different from those of natural predators. Natural predators of hoverflies have different visual and cognitive systems from humans, and they may encounter mimics in a different way. For example, whilst humans often encounter hoverflies at rest on vegetation, or in photographs or textbooks, where they are typically viewed from above, natural predators may approach hoverflies from the side or below. To test how viewing angle affects the perception of mimicry, images of mimetic hoverflies and their models (wasps and bees) were shown from different angles in an online survey. Participants were asked to distinguish between the images of models and mimics. The results show that the viewing angle does affect perceived mimicry in some species, although it does not provide a complete explanation for the persistence of imperfect mimicry in nature. The effect is also highly species-specific. This suggests that to understand better how selection has shaped mimetic accuracy in hoverflies and other taxa, further study is required of the viewing angles that predators utilize most commonly in nature.

2.
Oecologia ; 203(1-2): 1-11, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37733112

RESUMO

Phenological mismatches caused by climate change pose a major threat to global biodiversity, yet relatively few studies have reported population declines resulting from mismatch. It has been hypothesised that density effects may underlie this lack of observed responses by buffering against mismatch-induced population decline. We developed an individual-based model of the critically endangered Sinai baton blue butterfly (Pseudophilotes sinaicus) and its hostplant Sinai thyme (Thymus decussatus), parameterised using real field data, to test this hypothesis. Our model showed that the baton blue experiences demographic consequences under only 5 days of phenological mismatch, but that this threshold was increased to 14 days with the inclusion of density-dependent juvenile mortality. The inclusion of density effects also led to the replication of population cycles observed in nature, supporting the ability of our model to accurately represent the baton blue's ecology. These results add to a growing body of literature suggesting that density effects may underlie the observed lack of demographic responses to mismatch in wild populations. However, these buffers may be short-lived in extreme mismatch scenarios, providing a false sense of security against a looming threat of population collapse.


Assuntos
Borboletas , Animais , Ecologia , Dinâmica Populacional , Mudança Climática , Estações do Ano
3.
Glob Chang Biol ; 29(19): 5568-5581, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37548403

RESUMO

The increasing frequency and cost of zoonotic disease emergence due to global change have led to calls for the primary surveillance of wildlife. This should be facilitated by the ready availability of remotely sensed environmental data, given the importance of the environment in determining infectious disease dynamics. However, there has been little evaluation of the temporal predictiveness of remotely sensed environmental data for infection reservoirs in vertebrate hosts due to a deficit of corresponding high-quality long-term infection datasets. Here we employ two unique decade-spanning datasets for assemblages of infectious agents, including zoonotic agents, in rodents in stable habitats. Such stable habitats are important, as they provide the baseline sets of pathogens for the interactions within degrading habitats that have been identified as hotspots for zoonotic emergence. We focus on the enhanced vegetation index (EVI), a measure of vegetation greening that equates to primary productivity, reasoning that this would modulate infectious agent populations via trophic cascades determining host population density or immunocompetence. We found that EVI, in analyses with data standardised by site, inversely predicted more than one-third of the variation in an index of infectious agent total abundance. Moreover, in bipartite host occupancy networks, weighted network statistics (connectance and modularity) were linked to total abundance and were also predicted by EVI. Infectious agent abundance and, perhaps, community structure are likely to influence infection risk and, in turn, the probability of transboundary emergence. Thus, the present results, which were consistent in disparate forest and desert systems, provide proof-of-principle that within-site fluctuations in satellite-derived greenness indices can furnish useful forecasting that could focus primary surveillance. In relation to the well-documented global greening trend of recent decades, the present results predict declining infection burden in wild vertebrates in stable habitats; but if greening trends were to be reversed, this might magnify the already upwards trend in zoonotic emergence.


Assuntos
Ecossistema , Roedores , Animais , Animais Selvagens , Florestas
4.
Heliyon ; 9(2): e12501, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36816281

RESUMO

Climate is a vital factor that shapes habitat suitability for many species across space and time. Gazella subgutturosa (Goitered gazelle) is a globally vulnerable mammal already extinct in some areas of Armenia and Georgia and is highly threatened in other areas of its distribution. In this study, new data were gathered for 33 locations in north-eastern Iraq, and then together with literature data, Species Distribution Models (SDMs) were used to explore the geographical distribution of the gazelle under current and future climate change scenarios. We studied the relationship between seven climate variables and 43 occurrence records to predict habitat suitability of the gazelle under the current climate, and also under four future climate scenarios (RCP2.6 and RCP8.5 for both 2050 and 2080). Annual precipitation and isothermality had the most influence on the distribution of Gazella subgutturosa. The most suitable habitat in both the current and future scenarios was located in north-eastern Iraq close to the Iranian border near the Zagros Mountains. There was no difference in habitat suitability for the gazelle inside Iraqi Protected Areas (PAs) compared to outside the PAs. Using the occurrence records and IUCN Red List national assessments, we found Iraqi Goitered gazelle populations to be classified as Endangered (EN). Our results suggest urgent conservation planning is needed to save this species, including the establishment of new PAs. These results contribute new baseline information, which was currently missing Goitered gazelle in about Iraq, to the IUCN SSC Antelope Specialist Group, which will hopefully aid with future global assessments and conservation.

5.
Ecol Appl ; 32(8): e2695, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35732507

RESUMO

Large, citizen-science species databases are powerful resources for predictive species distribution modeling (SDM), yet they are often subject to sampling bias. Many methods have been proposed to correct for this, but there exists little consensus as to which is most effective, not least because the true value of model predictions is hard to evaluate without extensive independent field sampling. We present here a nationwide, independent field validation of distribution models of ancient and veteran trees, a group of organisms of high conservation importance, built using a large and internationally unique citizen-science database: the Ancient Tree Inventory (ATI). This validation exercise presents an opportunity to test the performance of different methods of correcting for sampling bias, in the search for the best possible prediction of ancient and veteran tree distributions in England. We fitted a variety of distribution models of ancient and veteran tree records in England in relation to environmental predictors and applied different bias correction methods, including spatial filtering, background manipulation, the use of bias files, and, finally, zero-inflated (ZI) regression models, a new method with great potential to investigate and remove sampling bias in species data. We then collected new independent field data through systematic surveys of 52 randomly selected 1-km2 grid squares across England to obtain abundance estimates of ancient and veteran trees. Calibration of the distribution models against the field data suggests that there are around eight to 10 times as many ancient and veteran trees present in England than the records currently suggest, with estimates ranging from 1.7 to 2.1 million trees compared to the 200,000 currently recorded in the ATI. The most successful bias correction method was systematic sampling of occurrence records, although the ZI models also performed well, significantly predicting field observations and highlighting both likely causes of undersampling and areas of the country in which many unrecorded trees are likely to be found. Our findings provide the first robust nationwide estimate of ancient and veteran tree abundance and demonstrate the enormous potential for distribution modeling based on citizen-science data combined with independent field validation to inform conservation planning.


Assuntos
Árvores , Veteranos , Humanos , Inglaterra
6.
Evolution ; 75(11): 2802-2815, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34464452

RESUMO

Hoverflies (Diptera: Syrphidae) provide an excellent opportunity to study the evolution of Batesian mimicry, where defenseless prey avoid predation by evolving to resemble defended "model" species. Although some hoverflies beautifully resemble their hymenopteran models, others seem to be poor mimics or are apparently nonmimetic. The reasons for this variation are still enigmatic despite decades of research. Here, we address this issue by mapping social-wasp mimicry across the phylogeny of Holarctic hoverflies. Using the "distance transform" technique, we calculate an objective measure of the abdominal pattern similarity between 167 hoverfly species and a widespread putative model, the social wasp, Vespula germanica. We find that good wasp mimicry has evolved several times, and may have also been lost, leading to the presence of nonmimics deep within clades of good mimics. Body size was positively correlated with similarity to the model, supporting previous findings that smaller species are often poorer mimics. Additionally, univoltine species were less accurate wasp mimics than multivoltine and bivoltine species. Hence, variation in the accuracy of Batesian mimics may reflect variation in the opportunity for selection caused by differences in prey value or signal perception (influenced by body size) and phenology or generation time (influenced by voltinism).


Assuntos
Mimetismo Biológico , Vespas , Animais , Vespas/genética
7.
Ecology ; 102(6): e03354, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33797755

RESUMO

Insects are the most ubiquitous and diverse group of eukaryotic organisms on Earth, forming a crucial link in terrestrial and freshwater food webs. They have recently become the subject of headlines because of observations of dramatic declines in some places. Although there are hundreds of long-term insect monitoring programs, a global database for long-term data on insect assemblages has so far remained unavailable. In order to facilitate synthetic analyses of insect abundance changes, we compiled a database of long-term (≥10 yr) studies of assemblages of insects (many also including arachnids) in the terrestrial and freshwater realms. We searched the scientific literature and public repositories for data on insect and arachnid monitoring using standardized protocols over a time span of 10 yr or longer, with at least two sampling events. We focused on studies that presented or allowed calculation of total community abundance or biomass. We extracted data from tables, figures, and appendices, and, for data sets that provided raw data, we standardized trapping effort over space and time when necessary. For each site, we extracted provenance details (such as country, state, and continent) as well as information on protection status, land use, and climatic details from publicly available GIS sources. In all, the database contains 1,668 plot-level time series sourced from 165 studies with samples collected between 1925 and 2018. Sixteen data sets provided here were previously unpublished. Studies were separated into those collected in the terrestrial realm (103 studies with a total of 1,053 plots) and those collected in the freshwater realm (62 studies with 615 plots). Most studies were from Europe (48%) and North America (29%), with 34% of the plots located in protected areas. The median monitoring time span was 19 yr, with 12 sampling years. The number of individuals was reported in 129 studies, the total biomass was reported in 13 studies, and both abundance and biomass were reported in 23 studies. This data set is published under a CC-BY license, requiring attribution of the data source. Please cite this paper if the data are used in publications, and respect the licenses of the original sources when using (part of) their data as detailed in Metadata S1: Table 1.


Assuntos
Aracnídeos , Animais , Europa (Continente) , Cadeia Alimentar , Humanos , Insetos , América do Norte
8.
Cleft Palate Craniofac J ; 58(11): 1348-1360, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33631972

RESUMO

OBJECTIVES: (1) To determine the incidence rate of velopharyngeal dysfunction (VPD) according to 7 speech criteria post-Furlow palatoplasty. (2) To find an anatomical measurement of the cleft palate (or combination of measurements) associated with the occurrence of VPD. STUDY DESIGN: Retrospective cohort study. PARTICIPANTS AND METHODS: Fifty-six patients with cleft palate ± cleft lip underwent palatoplasty with the Furlow technique at the age of 10 months. Pre-and post-palatoplasty cleft palate measurements were collected during the procedure. Three blinded speech-language pathologists (SLPs) retrospectively scored the patients from the chart data at age 4. Student t test and receiver operating characteristic curve analysis were used to evaluate the association and predictive capacity between cleft measurements and parameters (M&P) with all VPD criteria. RESULTS: The SLPs found an incidence of VPD according to 7 criteria: hypernasality (11%), audible nasal emission (4%), nasal rustle (14%), compensatory errors (4%), impairment of speech understandability (7%), and impairment of speech acceptability (16%). The SLPs recommended a secondary surgical procedure in 5 patients (9%). A statistically significant association was found between, respectively, 17 and 5 M&P and the occurrence of compensatory errors and audible nasal emission. Our data suggest that the length of the cleft, the cleft area, and the postoperative transversal size of the nasopharynx are the best indicators of the future positivity of VPD criteria. CONCLUSION: The size of the postoperative transverse nasopharyngeal area during the primary cleft palate procedure may become the focus of the next generation of cleft surgeons to reduce the incidence of VPD.


Assuntos
Fissura Palatina , Insuficiência Velofaríngea , Pré-Escolar , Fissura Palatina/cirurgia , Humanos , Lactente , Nasofaringe , Estudos Retrospectivos , Fala , Insuficiência Velofaríngea/epidemiologia , Insuficiência Velofaríngea/cirurgia
9.
BMC Ecol ; 20(1): 35, 2020 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-32590973

RESUMO

BACKGROUND: Spatial conservation prioritisation (SCP) is a set of computational tools designed to support the efficient spatial allocation of priority areas for conservation actions, but it is subject to many sources of uncertainty which should be accounted for during the prioritisation process. We quantified the sensitivity of an SCP application (using software Zonation) to possible sources of uncertainty in data-poor situations, including the use of different surrogate options; correction for sampling bias; how to integrate connectivity; the choice of species distribution modelling (SDM) algorithm; how cells are removed from the landscape; and two methods of assigning weights to species (red-list status or prediction uncertainty). Further, we evaluated the effectiveness of the Egyptian protected areas for conservation, and spatially allocated the top priority sites for further on-the-ground evaluation as potential areas for protected areas expansion. RESULTS: Focal taxon (butterflies, reptiles, and mammals), sampling bias, connectivity and the choice of SDM algorithm were the most sensitive parameters; collectively these reflect data quality issues. In contrast, cell removal rule and species weights contributed much less to overall variability. Using currently available species data, we found the current effectiveness of Egypt's protected areas for conserving fauna was low. CONCLUSIONS: For SCP to be useful, there is a lower limit on data quality, requiring data-poor countries to improve sampling strategies and data quality to obtain unbiased data for as many taxa as possible. Since our sensitivity analysis may not generalise, conservation planners should use sensitivity analyses more routinely, particularly relying on more than one combination of SDM algorithm and surrogate group, consider correction for sampling bias, and compare the spatial patterns of predicted priority sites using a variety of settings. The sensitivity of SCP to connectivity parameters means that the responses of each species to habitat loss are important knowledge gaps.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Animais , Ecossistema , Répteis
10.
Cleft Palate Craniofac J ; 57(7): 819-827, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32041415

RESUMO

OBJECTIVES: (1) To assess the evolution of prepalatoplasty sleep oximetry (PRESO) and postpalatoplasty sleep oximetry (POSSO) in cleft patients and (2) to evaluate the impact of the size of the nasopharynx on PRESO and POSSO values. STUDY DESIGN: Retrospective cohort study. PATIENTS AND METHODS: In 81 patients with cleft palate and/or cleft lip, the following data were prospectively collected: patient demographics and prepalatoplasty cleft palate measurements. All the patients had at least 1 PRESO and POSSO. A Kaplan-Meier curve was obtained from all the sleep oximetry results. Transverse nasopharyngeal area (TNA) pre- and postvalues were compared for each group with paired t tests, while analysis of variance was used to compare TNA pre- and postscores between the groups with a Bonferroni correction for multiple comparisons. RESULTS: POSSO results were normal or showed mild desaturations in most patients in the few weeks following palatoplasty. For the cohort, no statistically significant changes were found between PRESO and POSSO values. A 2-fold variation in the area of the TNA was found before palatoplasty within identical cleft malformation cases. No statistically significant association was found between the TNA or the a/30 - b1 parameter values and the sleep study scores. CONCLUSIONS: The patients with the smaller nasopharyngeal areas presented identical PRESO and POSSO results when compared to those with larger nasopharyngeal sizes. Future studies should address the possible association between prepalatoplasty and postpalatoplasty TNAs and the occurrence of velopharyngeal deficiency later in life.


Assuntos
Fissura Palatina , Insuficiência Velofaríngea , Fissura Palatina/cirurgia , Humanos , Nasofaringe , Oximetria , Palato Mole , Estudos Retrospectivos , Sono , Resultado do Tratamento
11.
Zootaxa ; 4577(2): zootaxa.4577.2.1, 2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-31715720

RESUMO

All known Egyptian taxa of the family Syrphidae (flower flies or hover flies) are systematically catalogued. A total number of 51 species belonging to 22 genera, 7 tribes and 2 subfamilies has been treated, including eight species that are listed as unconfirmed records from Egypt. Data for this study have been compiled from both available literature and specimens collected from different Egyptian localities by the authors or preserved in the main Egyptian insect collections. Old World synonymies, type localities, world distributions by biogeographic realm(s) and country, Egyptian localities and activity periods are provided. Remarks on habitat, habits and biology of particular species are provided as well. Two species, Melanostoma scalare (Fabricius) and Eristalis arbustorum (Linnaeus) are recorded for the first time from Egypt.


Assuntos
Dípteros , Animais , Biologia , Egito
12.
Curr Biol ; 29(14): R697-R699, 2019 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-31336089

RESUMO

There are some strange tales in the history of Natural History, and few more so than the story of animal migration. It took centuries to work out some of the astonishing features of bird migration: now a new study of hoverflies points out some more that occur among the insects.


Assuntos
Ecossistema , Polinização , Migração Animal , Animais , Proteção de Cultivos , Estações do Ano
13.
Parasitology ; 146(1): 50-73, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29921333

RESUMO

The importance of parasites as a selective force in host evolution is a topic of current interest. However, short-term ecological studies of host-parasite systems, on which such studies are usually based, provide only snap-shots of what may be dynamic systems. We report here on four surveys, carried out over a period of 12 years, of helminths of spiny mice (Acomys dimidiatus), the numerically dominant rodents inhabiting dry montane wadis in the Sinai Peninsula. With host age (age-dependent effects on prevalence and abundance were prominent) and sex (female bias in abundance in helminth diversity and in several taxa including Cestoda) taken into consideration, we focus on the relative importance of temporal and spatial effects on helminth infracommunities. We show that site of capture is the major determinant of prevalence and abundance of species (and higher taxa) contributing to helminth community structure, the only exceptions being Streptopharaus spp. and Dentostomella kuntzi. We provide evidence that most (notably the Spiruroidea, Protospirura muricola, Mastophorus muris and Gongylonema aegypti, but with exceptions among the Oxyuroidae, e.g. Syphacia minuta), show elements of temporal-site stability, with a rank order of measures among sites remaining similar over successive surveys. Hence, there are some elements of predictability in these systems.


Assuntos
Helmintíase Animal/epidemiologia , Helmintíase Animal/parasitologia , Murinae/parasitologia , Doenças dos Roedores/epidemiologia , Doenças dos Roedores/parasitologia , Fatores Etários , Animais , Distribuição Binomial , Egito/epidemiologia , Feminino , Masculino , Prevalência , Fatores Sexuais , Análise Espacial , Fatores de Tempo
14.
PLoS One ; 12(11): e0187714, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29136659

RESUMO

Climate change is one of the most difficult of challenges to conserving biodiversity, especially for countries with few data on the distributions of their taxa. Species distribution modelling is a modern approach to the assessment of the potential effects of climate change on biodiversity, with the great advantage of being robust to small amounts of data. Taking advantage of a recently validated dataset, we use the medicinal plants of Egypt to identify hotspots of diversity now and in the future by predicting the effect of climate change on the pattern of species richness using species distribution modelling. Then we assess how Egypt's current Protected Area network is likely to perform in protecting plants under climate change. The patterns of species richness show that in most cases the A2a 'business as usual' scenario was more harmful than the B2a 'moderate mitigation' scenario. Predicted species richness inside Protected Areas was higher than outside under all scenarios, indicating that Egypt's PAs are well placed to help conserve medicinal plants.


Assuntos
Mudança Climática , Plantas Medicinais/classificação , Biodiversidade , Conservação dos Recursos Naturais , Egito , Previsões
15.
Vector Borne Zoonotic Dis ; 17(7): 483-494, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28541836

RESUMO

Bartonella spp. are parasites of mammalian erythrocytes and endothelial cells, transmitted by blood-feeding arthropod ectoparasites. Different species of rodents may constitute the main hosts of Bartonella, including several zoonotic species of Bartonella. The aim of this study was to identify and compare Bartonella species and genotypes isolated from rodent hosts from the South Sinai, Egypt. Prevalence of Bartonella infection was assessed in rodents (837 Acomys dimidiatus, 73 Acomys russatus, 111 Dipodillus dasyurus, and 65 Sekeetamys calurus) trapped in 2000, 2004, 2008, and 2012 in four dry montane wadis around St. Katherine town in the Sinai Mountains. Total DNA was extracted from blood samples, and PCR amplification and sequencing of the Bartonella-specific 860-bp gene fragment of rpoB and the 810-bp gene fragment of gltA were used for molecular and phylogenetic analyses. The overall prevalence of Bartonella in rodents was 7.2%. Prevalence differed between host species, being 30.6%, 10.8%, 9.6%, and 3.6% in D. dasyurus, S. calurus, A. russatus, and A. dimidiatus, respectively. The phylogenetic analyses of six samples of Bartonella (five from D. dasyurus and one from S. calurus) based on a fragment of the rpoB gene, revealed the existence of two distinct genetic groups (with 95-96% reciprocal sequence identity), clustering with several unidentified isolates obtained earlier from the same rodent species, and distant from species that have already been described (90-92% of sequence identity to the closest match from the GenBank reference database). Thus, molecular and phylogenetic analyses led to the description of two species: Candidatus Bartonella fadhilae n. sp. and Candidatus Bartonella sanaae n. sp. The identification of their vectors and the medical significance of these species need further investigation.


Assuntos
Infecções por Bartonella/veterinária , Bartonella/classificação , Gerbillinae/microbiologia , Animais , Bartonella/genética , Bartonella/isolamento & purificação , Infecções por Bartonella/epidemiologia , Infecções por Bartonella/microbiologia , DNA Bacteriano , Egito/epidemiologia , Genótipo , Filogenia
16.
Urol Oncol ; 34(12): 531.e7-531.e14, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27449687

RESUMO

PURPOSE: Assessing the unmet needs of cancer patients can help providers tailor health care services to patients' specific needs. This study examines whether the unmet informational and supportive care needs of the patients with muscle-invasive bladder cancer vary by the patients' age, sex, or individual treatment choices. METHODS AND MATERIALS: Participants (N = 30 survivors; 73.3% men) were recruited from the Mount Sinai Medical Center and through advertisements posted on a national Bladder Cancer Advocacy Network website between December 2011 and September 2012. Data were collected through individual interviews and electronic medical record review. A prior qualitative study of this cohort, using immersion/crystallization approach, confirmed the prevalence of unmet needs across the disease trajectory. This is a secondary quantitative analysis of the initial interview data we collected (i.e., quantitative analyses of transformed qualitative data using Chi-square and Fisher exact tests) to examine differences in unmet needs based on the patient's age, sex, and treatment choices. RESULTS: Younger patients (<60y) were less satisfied with the treatment information received presurgery and more likely to report posttreatment complications, choose a neobladder, and seek and receive professional support regarding sexual function, than were older patients (P<0.05). More women than men reported difficulties with self-care and relied on themselves in disease self-management as opposed to relying on spousal support (P<0.05). Patients with neobladder were more likely to report difficulties with urinary incontinence and deterioration in sexual function, whereas patients with ileal conduit were more likely to require spousal help with self-care. Patients who received chemotherapy were significantly more likely to report changes in everyday life (P<0.05). Lastly, regardless of age, sex, or treatment choice, up to 50% of patients reported feeling depressed before or after treatment. CONCLUSIONS: Unmet informational and supportive needs of patients with muscle-invasive bladder cancer during survivorship, and vary by age, sex, and treatment choices. Educational and psychological assessments as well as clinical interventions should be tailored to a patient's specific unmet needs, and to specific clinical and demographic characteristics.


Assuntos
Carcinoma de Células de Transição/cirurgia , Cistectomia , Necessidades e Demandas de Serviços de Saúde , Educação de Pacientes como Assunto , Apoio Social , Neoplasias da Bexiga Urinária/cirurgia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células de Transição/patologia , Carcinoma de Células de Transição/terapia , Quimioterapia Adjuvante , Terapia Combinada , Cistectomia/psicologia , Depressão/epidemiologia , Depressão/etiologia , Humanos , Pessoa de Meia-Idade , Músculo Liso/patologia , Terapia Neoadjuvante , Invasividade Neoplásica , Satisfação do Paciente , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/psicologia , Autocuidado , Fatores Sexuais , Cônjuges , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/terapia , Derivação Urinária/psicologia
17.
Parasit Vectors ; 9: 195, 2016 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-27059180

RESUMO

BACKGROUND: Long-term field studies of parasite communities are rare but provide a powerful insight into the ecological processes shaping host-parasite interactions. The aim of our study was to monitor long-term trends in the haemoparasite communities of spiny mice (Acomys dimidiatus) and to identify the principal factors responsible for changes over a 12 year period. METHODS: To this end we sampled four semi-isolated populations of mice (n = 835) in 2000, 2004, 2008 and 2012 in four dry montane valleys (wadis) located in the Sinai Massif, Egypt. RESULTS: Overall 76.2 % of spiny mice carried at least one of the five haemoparasite genera (Babesia, Bartonella, Haemobartonella, Hepatozoon, Trypanosoma) recorded in the study. Prevalence of haemoparasites varied significantly between the sites with the highest overall prevalence in Wadi Tlah and the lowest in W. El Arbaein, and this changed significantly with time. In the first two surveys there was little change in prevalence, but by 2008, when the first signs of a deepening drought in the region had become apparent, prevalence began to drift downwards, and by 2012 prevalence had fallen to the lowest values recorded from all four sites over the entire 12-year period. The overall mean species richness was 1.2 ± 0.03, which peaked in 2004 and then dropped by more than 50 % by 2012. Species richness was highest among mice from Wadi Tlah and peaked in age class 2 mice (young adults). Site was the most significant factor affecting the prevalence of individual parasite species, with Trypanosoma acomys and Hepatozoon sp. occurring mainly in two wadis (W. Tlah & W. Gharaba). In four of the five genera recorded in the study we observed a significant drop in prevalence or/and abundance since 2004, the exception being Hepatozoon sp. CONCLUSIONS: During the 12-year-long period of study in the Sinai, we observed dynamic changes and possibly even cycles of prevalence and abundance of infections which differed depending on parasite species. Although the exact reasons cannot be identified at this time, we hypothesize that the effects of a 15-year-long scarcity of rainfall in the local environment and a fall in host densities over the period of study may have been responsible for a drop in transmission rates, possibly by a negative impact on vector survival.


Assuntos
Apicomplexa/isolamento & purificação , Bacteriemia/veterinária , Bactérias/isolamento & purificação , Kinetoplastida/isolamento & purificação , Murinae/parasitologia , Doenças Parasitárias/epidemiologia , Animais , Apicomplexa/classificação , Bacteriemia/epidemiologia , Bacteriemia/microbiologia , Bactérias/classificação , Egito/epidemiologia , Kinetoplastida/classificação , Doenças Parasitárias/parasitologia , Prevalência , Análise Espaço-Temporal
18.
Proc Biol Sci ; 283(1842)2016 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-28120792

RESUMO

Mimicry is considered a classic example of the elaborate adaptations that natural selection can produce, yet often similarity between Batesian (harmless) mimics and their unpalatable models is far from perfect. Variation in mimetic accuracy is a puzzle, as natural selection should favour mimics that are hardest to distinguish from their models. Numerous hypotheses exist to explain the persistence of inaccurate mimics, but most have rarely or never been tested against empirical observations from wild populations. One reason for this is the difficulty in measuring pattern similarity, a key aspect of mimicry. Here, we use a recently developed method, based on the distance transform of binary images, to quantify pattern similarity both within and among species for a group of hoverflies and their hymenopteran models. This allowed us to test three key hypotheses regarding inaccurate mimicry. Firstly, we tested the prediction that selection should be more relaxed in less accurate mimics, but found that levels of phenotypic variation are similar across most hoverfly species. Secondly, we found no evidence that mimics have to compromise between accuracy to multiple model species. However, we did find that darker-coloured hoverflies are less accurate mimics, which could lead to a trade-off between mimicry and thermoregulation in temperate regions. Our results shed light on a classic problem concerning the limitations of natural selection.


Assuntos
Evolução Biológica , Mimetismo Biológico , Himenópteros/anatomia & histologia , Pigmentação , Seleção Genética , Animais , Cor , Comportamento Predatório
19.
Parasit Vectors ; 7: 572, 2014 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-25487227

RESUMO

BACKGROUND: Although a number of new species of Babesia/Theileria have been described recently, there are still relatively few reports of species from Africa. In this study based on the evaluation of morphology and phylogenetic relationships, we describe a novel species from Wagner's gerbil, Babesia behnkei n. sp. METHODS: Rodents (n = 1021) were sampled in four montane valleys (wadies) in 2000, 2004, 2008 and 2012 in the Sinai Mountains, Egypt. The overall prevalence of Babesia spp. was highest in the Wagner's gerbil (Dipodillus dasyurus; 38.7%) in comparison to the prevalence in the spiny mice species, Acomys dimidiatus and A. russatus. Morphological investigations were conducted for the comparison of trophozoites of the novel species of Babesia with the B. microti King's 67 reference strain. Thirty-two isolates derived from D. dasyurus over a 9 year period (2004-2012) from two wadies (29 isolates from Wadi Gebel and 3 from Wadi El-Arbaein) were investigated by microscopic, molecular and phylogenetic analysis. A near-full-length sequence of the 18S rRNA gene and the second internal transcribed spacer (ITS2) region were amplified, sequenced and used for the construction of phylogenetic trees. RESULTS: A novel species of Babesia was identified in two isolated populations of D. dasyurus. Phylogenetic analysis of 18S rDNA and ITS2 sequences revealed that B. behnkei n. sp. is most closely related to B. lengau from cheetahs from South Africa and to Nearctic species found only in North America (the pathogenic B. duncani and B. conradae) and that it is more distant to the cosmopolitan rodent parasite B. microti. Trophozoites of B. behnkei were smaller and less polymorphic than trophozoites of B. microti. CONCLUSION: Babesia behnkei n. sp. is a novel species of the 'Duncani group' maintained in isolated populations of Dipodillus dasyurus occurring in the Sinai Mountains of Egypt.


Assuntos
Babesia/classificação , Babesiose/parasitologia , Gerbillinae , Doenças dos Roedores/parasitologia , Animais , Babesia/isolamento & purificação , Babesiose/epidemiologia , DNA Espaçador Ribossômico/genética , Egito/epidemiologia , Filogenia , Doenças dos Roedores/epidemiologia
20.
Ecol Lett ; 13(5): 543-52, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20236160

RESUMO

The spatial insurance hypothesis indicates that connectivity is an important attribute of natural ecosystems that sustains both biodiversity and ecosystem function. We tested the hypothesis by measuring the impact of manipulating connectivity in experimental metacommunties of a natural and diverse microecosystem. Isolation led to the extinction of large-bodied apex predators, subsequently followed by increases in prey species abundance. This trophic cascade was associated with significantly altered carbon and nitrogen fluxes in fragmented treatments. The ecosystem impacts were characteristic of a function debt because they persisted for several generations after the initial loss of connectivity. Local extinctions and disruption of ecosystem processes were mitigated, and even reversed, by the presence of corridors in the connected metacommunities, although these beneficial effects were unexpectedly delayed. We hypothesized that corridors maintained grazer movement between fragments, which enhanced microbial activity, and decomposition in comparison to isolated fragments. Our results indicate that knowledge of habitat connectivity and spatial processes is essential to understand the magnitude and timing of ecosystem perturbation in fragmented landscapes.


Assuntos
Ecossistema , Extinção Biológica , Animais , Artrópodes/metabolismo , Carbono/metabolismo , Dióxido de Carbono/metabolismo , Modelos Teóricos , Nitrogênio/metabolismo
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