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1.
PLoS One ; 19(7): e0307922, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39074126

RESUMO

Although both clinical data and animal models suggest cardiovascular benefits following administration of Dipeptidyl Peptidase 4 (DPP-4) inhibitors, the underlying mechanisms remain unclear. We therefore sought to evaluate the effect of the DPP-4 inhibitor sitagliptin on myocardial fibrosis, and insulin signaling in chronic myocardial ischemia using a swine model. An ameroid constrictor placement on the left coronary circumflex artery of thirteen Yorkshire swine to model chronic myocardial ischemia. After two weeks of recovery, swine were assigned to one of two groups: control (CON, n = 8), or sitagliptin 100mg daily (SIT, n = 5). After 5 weeks of treatment, the swine underwent terminal harvest with collection of myocardial tissue. Fibrosis was quantified using Masson's trichrome. Protein expression was quantified by Immunoblotting. Trichrome stain demonstrated a significant decrease in perivascular and interstitial fibrosis in the SIT group relative to CON (all p<0.05). Immunoblot showed a reduction in Jak2, the pSTAT3 to STAT 3 Ratio, pSMAD 2/3, and SMAD 2/3, and an increase in STAT 3 in the SIT group relative to CON (all p<0.05). SIT treatment was associated with increased expression of insulin receptor one and decreased expression of makers for insulin resistance, including phospho-PKC- alpha, RBP-4, SIRT1, and PI3K (p<0.05). Sitagliptin results in a reduction in perivascular and interstitial fibrosis and increased insulin sensitivity in chronically ischemic swine myocardium. This likely contributes to the improved cardiovascular outcomes seen with DPP-4 inhibitors.


Assuntos
Inibidores da Dipeptidil Peptidase IV , Modelos Animais de Doenças , Fibrose , Insulina , Isquemia Miocárdica , Miocárdio , Transdução de Sinais , Fosfato de Sitagliptina , Animais , Fosfato de Sitagliptina/farmacologia , Fosfato de Sitagliptina/uso terapêutico , Inibidores da Dipeptidil Peptidase IV/farmacologia , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Insulina/metabolismo , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/tratamento farmacológico , Isquemia Miocárdica/patologia , Suínos , Miocárdio/metabolismo , Miocárdio/patologia , Doença Crônica
2.
Artigo em Inglês | MEDLINE | ID: mdl-38879117

RESUMO

INTRODUCTION: Sodium-glucose cotransporter-2 inhibitors are antidiabetic medications that have been shown to decrease cardiovascular events and heart failure-related mortality in clinical studies. We attempt to examine the complex interplay between metabolic syndrome and the sodium-glucose cotransporter-2 inhibitor canagliflozin (CAN) in a clinically relevant model of chronic myocardial ischemia. METHODS: Twenty-one Yorkshire swine were fed a high-fat diet starting at 6 weeks of age to induce metabolic syndrome. At 11 weeks, all underwent placement of an ameroid constrictor around the left circumflex coronary artery to induce chronic myocardial ischemia. After 2 weeks, swine received either control (CON) (n = 11) or CAN 300 mg by mouth daily (n = 10) for 5 weeks, whereupon all underwent terminal harvest. RESULTS: There was a significant increase in cardiac output and heart rate with a decrease in pulse pressure in the CAN group compared with CON (all P values < .05). The CAN group had a significant increase in capillary density (P = .02). There was no change in myocardial perfusion or arteriolar density. CAN induced a significant increase in markers of angiogenesis, including Phospho-endothelial nitric oxide synthase, Endothelial nitric oxide synthase, vascular endothelial growth factor receptor-1, heat shock protein 70, and extracellular signal-regulated kinases (all P values < .05), plausibly resulting in capillary angiogenesis. CONCLUSIONS: CAN treatment leads to a significant increase in capillary density and augmented cardiac function in a swine model of chronic myocardial ischemia in the setting of metabolic syndrome. This work further elucidates the mechanism of sodium-glucose cotransporter-2 inhibitors in patients with cardiac disease; however, more studies are needed to determine if this increase in capillary density plays a role in the improvements seen in clinical studies.

3.
PLoS One ; 19(2): e0297102, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38377079

RESUMO

BACKGROUND: Quantifying movement behaviours over 24-hours enables the combined effects of and inter-relations between sleep, sedentary time and physical activity (PA) to be understood. This is the first study describing 24-hour movement behaviours in school-aged children and adolescents in South-East Asia. Further aims were to investigate between-participant differences in movement behaviours by demographic characteristics and timing of data collection during Ramadan and COVID-19 restrictions. METHODS: Data came from the South-East Asia Community Observatory health surveillance cohort, 2021-2022. Children aged 7-18 years within selected households in Segamat, Malaysia wore an Axivity AX6 accelerometer on their wrist for 24 hours/day over 7 days, completed the PAQ-C questionnaire, and demographic information was obtained. Accelerometer data was processed using GGIR to determine time spent asleep, inactive, in light-intensity PA (LPA) and moderate-to-vigorous PA (MVPA). Differences in accelerometer-measured PA by demographic characteristics (sex, age, ethnicity, socioeconomic group) were explored using univariate linear regression. Differences between data collected during vs outside Ramadan or during vs after COVID-19 restrictions, were investigated through univariate and multiple linear regressions, adjusted for age, sex and ethnicity. RESULTS: The 491 participants providing accelerometer data spent 8.2 (95% confidence interval (CI) = 7.9-8.4) hours/day asleep, 12.4 (95% CI = 12.2-12.7) hours/day inactive, 2.8 (95% CI = 2.7-2.9) hours/day in LPA, and 33.0 (95% CI = 31.0-35.1) minutes/day in MVPA. Greater PA and less time inactive were observed in boys vs girls, children vs adolescents, Indian and Chinese vs Malay children and higher income vs lower income households. Data collection during Ramadan or during COVID-19 restrictions were not associated with MVPA engagement after adjustment for demographic characteristics. CONCLUSIONS: Demographic characteristics remained the strongest correlates of accelerometer-measured 24-hour movement behaviours in Malaysian children and adolescents. Future studies should seek to understand why predominantly girls, adolescents and children from Malay ethnicities have particularly low movement behaviours within Malaysia.


Assuntos
COVID-19 , Exercício Físico , Masculino , Criança , Feminino , Humanos , Adolescente , Estudos Transversais , Inquéritos e Questionários , Acelerometria , COVID-19/epidemiologia
4.
Front Microbiol ; 15: 1332970, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38404602

RESUMO

The vectorial capacity of mosquitoes, which influences the dynamics of vector-borne disease transmission, is intricately linked to mosquito abundance and the composition and diversity of their associated microbiomes. However, the influence of environmental factors on mosquito populations and microbiome diversity remains underexplored. Here we examined the effects of seasonality and developed land cover on Culex mosquito abundance and bacterial diversity. Biweekly field sampling of female Culex mosquitoes was conducted using gravid and CDC light traps, spanning summer to autumn across varying developed land cover levels in two urban areas in Central Illinois. Mosquito abundance was assessed by the number of mosquitoes captured per trap night and compared across seasons and developed levels. The mean mosquito abundance for gravid and light traps was 12.96 ± 2.15 and 7.67 ± 1.44, respectively. Notably, higher levels of developed land cover exhibited higher Culex abundance than the low level for light traps, but no significant difference was found between summer and early autumn. In gravid traps, no significant differences were detected across seasons or developed levels. Microbial analysis of the mosquito microbiome revealed that Proteobacteria and Wolbachia, with a mean relative abundance of 80.77 and 52.66% respectively, were identified as the most dominant bacterial phylum and genus. Their relative abundance remained consistent across seasons and developed land cover levels, with negligible variations. Alpha diversity, as measured by observed species, Chao1, Shannon, and Simpson, showed slightly higher values in early-autumn compared to late-summer. A notable pattern of bacterial diversity, as indicated by all four diversity indexes, is evident across varying levels of land development. Significantly, high or intermediate developed levels consistently showed reduced alpha diversity when compared to the lower level. This underscores the pronounced impact of anthropogenic ecological disturbances in shaping mosquito microbiomes. Beta diversity analysis revealed no significant dissimilarities in bacterial community composition across seasons and developed levels, although some separation was noted among different levels of developed land cover. These findings highlight the significant role of environmental factors in shaping mosquito abundance and their associated microbiomes, with potential implications for the vectorial capacity in the transmission of vector-borne diseases.

5.
Parasit Vectors ; 16(1): 434, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993953

RESUMO

BACKGROUND: Estimating arbovirus transmission potential requires a mechanistic understanding of how environmental factors influence the expression of adult mosquito traits. While preimaginal exposure to environmental factors can have profound effects on adult traits, tracking and predicting these effects remains challenging. METHODS: Using Aedes albopictus and a structural equation modeling approach, we explored how larval nutrition and temperature jointly affect development rate and success, female body size, and whether these metrics capture carry-over effects on adult female longevity. Additionally, we investigated how larval diet and temperature affect the baseline expression of 10 immune genes. RESULTS: We found that larval development success was primarily determined by diet, while temperature and diet both affected development rate and female body size. Under a low larval diet, pupal wet weight and wing length both declined with increasing temperature. In contrast, responses of the two morphometric measures to rearing temperature diverged when females were provided higher larval nutrition, with pupal wet weight increasing and wing length decreasing at higher temperatures. Our analyses also revealed opposing relationships between adult female lifespan and the two morphometric measures, with wing length having a positive association with longevity and pupal weight a negative association. Larval diet indirectly affected adult longevity, and the time to pupation was negatively correlated with longevity. The expression of eight immune genes from the toll, JAK-STAT and Imd pathways was enhanced in mosquitoes with higher nutrition. CONCLUSIONS: Our results highlight deficiencies from using a single body size measure to capture carry-over effects on adult traits. Further studies of larval development rate under varying environmental conditions and its potential for tracking carry-over effects on vectorial capacity are warranted.


Assuntos
Aedes , Longevidade , Feminino , Animais , Temperatura , Larva/fisiologia , Dieta , Aedes/fisiologia , Tamanho Corporal
6.
Commun Biol ; 6(1): 1123, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932414

RESUMO

Diet-induced nutritional stress can influence pathogen transmission potential in mosquitoes by impacting life history traits, infection susceptibility, and immunity. To investigate these effects, we manipulate mosquito diets at larval and adult stages, creating two nutritional levels (low and normal), and expose adults to dengue virus (DENV). We observe that egg number is reduced by nutritional stress at both stages and viral exposure separately and jointly, while the likelihood of laying eggs is exclusively influenced by adult nutritional stress. Adult nutritional stress alone shortens survival, while any pairwise combination between both-stage stress and viral exposure have a synergistic effect. Additionally, adult nutritional stress increases susceptibility to DENV infection, while larval nutritional stress likely has a similar effect operating via smaller body size. Furthermore, adult nutritional stress negatively impacts viral titers in infected mosquitoes; however, some survive and show increased titers over time. The immune response to DENV infection is overall suppressed by larval and adult nutritional stress, with specific genes related to Toll, JAK-STAT, and Imd immune signaling pathways, and antimicrobial peptides being downregulated. Our findings underscore the importance of nutritional stress in shaping mosquito traits, infection outcomes, and immune responses, all of which impact the vectorial capacity for DENV transmission.


Assuntos
Aedes , Vírus da Dengue , Dengue , Animais , Vírus da Dengue/fisiologia , Larva , Peptídeos Antimicrobianos
7.
Parasit Vectors ; 16(1): 2, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36593496

RESUMO

BACKGROUND: West Nile virus (WNV), primarily vectored by mosquitoes of the genus Culex, is the most important mosquito-borne pathogen in North America, having infected thousands of humans and countless wildlife since its arrival in the USA in 1999. In locations with dedicated mosquito control programs, surveillance methods often rely on frequent testing of mosquitoes collected in a network of gravid traps (GTs) and CO2-baited light traps (LTs). Traps specifically targeting oviposition-seeking (e.g. GTs) and host-seeking (e.g. LTs) mosquitoes are vulnerable to trap bias, and captured specimens are often damaged, making morphological identification difficult. METHODS: This study leverages an alternative mosquito collection method, the human landing catch (HLC), as a means to compare sampling of potential WNV vectors to traditional trapping methods. Human collectors exposed one limb for 15 min at crepuscular periods (5:00-8:30 am and 6:00-9:30 pm daily, the time when Culex species are most actively host-seeking) at each of 55 study sites in suburban Chicago, Illinois, for two summers (2018 and 2019). RESULTS: A total of 223 human-seeking mosquitoes were caught by HLC, of which 46 (20.6%) were mosquitoes of genus Culex. Of these 46 collected Culex specimens, 34 (73.9%) were Cx. salinarius, a potential WNV vector species not thought to be highly abundant in upper Midwest USA. Per trapping effort, GTs and LTs collected > 7.5-fold the number of individual Culex specimens than HLC efforts. CONCLUSIONS: The less commonly used HLC method provides important insight into the complement of human-biting mosquitoes in a region with consistent WNV epidemics. This study underscores the value of the HLC collection method as a complementary tool for surveillance to aid in WNV vector species characterization. However, given the added risk to the collector, novel mitigation methods or alternative approaches must be explored to incorporate HLC collections safely and strategically into control programs.


Assuntos
Culex , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Feminino , Humanos , Mosquitos Vetores , Animais Selvagens , Controle de Mosquitos/métodos
9.
J Med Entomol ; 59(5): 1625-1635, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-35857653

RESUMO

In the United States, the Gulf Coast tick (Amblyomma maculatum Koch) is a species of growing medical and veterinary significance, serving as the primary vector of the pathogenic bacterium, Rickettsia parkeri (Rickettsiales: Rickettsiaceae), in humans and the apicomplexan parasite, Hepatozoon americanum, in canines. Ongoing reports of A. maculatum from locations outside its historically reported distribution in the southeastern United States suggest the possibility of current and continuing range expansion. Using an ecological niche modeling approach, we combined new occurrence records with high-resolution climate and land cover data to investigate environmental drivers of the current distribution of A. maculatum in the United States. We found that environmental suitability for A. maculatum varied regionally and was primarily driven by climatic factors such as annual temperature variation and seasonality of precipitation. We also found that presence of A. maculatum was associated with open habitat with minimal canopy cover. Our model predicts large areas beyond the current distribution of A. maculatum to be environmentally suitable, suggesting the possibility of future northward and westward range expansion. These predictions of environmental suitability may be used to identify areas at potential risk for establishment and to guide future surveillance of A. maculatum in the United States.


Assuntos
Eucoccidiida , Ixodidae , Rickettsia , Amblyomma , Animais , Vetores de Doenças , Cães , Humanos , Ixodidae/microbiologia , Sudeste dos Estados Unidos/epidemiologia
10.
Environ Entomol ; 51(3): 586-594, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35552675

RESUMO

The Asian tiger mosquito, Aedes albopictus (Skuse), is a public health threat because it can potentially transmit multiple pathogenic arboviruses, exhibits aggressive diurnal biting, and is highly invasive. As Ae. albopictus moved northward into the United States, the limits of expansion were predicted as locations with a mean January temperature warmer than -2.5°C. We postulated that the range of Ae. albopictus could exceed these temperature limits if eggs in diapause overwinter in tires that provide an insulating effect from extreme temperatures. Fifteen tires with Ae. albopictus and Aedes triseriatus (Say) eggs, a native cold hardy species, were placed outside at five locations along a latitudinal gradient in Wisconsin and Illinois during the winter of 2018-2019; notably, in January 2019, a regional arctic air event brought the lowest temperatures recorded in over 20 yr. External and internal tire temperatures were recorded at 3 hr intervals, and egg survival was recorded after six months. Aedes albopictus eggs survived only from tires at northernmost locations. The mean internal January temperature of tires that supported survival was -1.8°C, while externally the mean temperature was -5.3°C, indicating that tires provided an average of +3.5°C of insulation. Tires that supported egg survival also had over 100 mm of snow cover during January. In the absence of snow cover, tires across the study area provided an average +0.79°C [95% CI 0.34-1.11] insulation. This work provides strong argument for the inclusion of microhabitats in models of dispersal and establishment of Ae. albopictus and other vector species.


Assuntos
Aedes , Animais , Temperatura Baixa , Mosquitos Vetores , Estações do Ano , Neve , Estados Unidos
12.
Ecol Evol ; 11(17): 12051-12063, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34522360

RESUMO

Camera traps have become an extensively utilized tool in ecological research, but the manual processing of images created by a network of camera traps rapidly becomes an overwhelming task, even for small camera trap studies.We used transfer learning to create convolutional neural network (CNN) models for identification and classification. By utilizing a small dataset with an average of 275 labeled images per species class, the model was able to distinguish between species and remove false triggers.We trained the model to detect 17 object classes with individual species identification, reaching an accuracy up to 92% and an average F1 score of 85%. Previous studies have suggested the need for thousands of images of each object class to reach results comparable to those achieved by human observers; however, we show that such accuracy can be achieved with fewer images.With transfer learning and an ongoing camera trap study, a deep learning model can be successfully created by a small camera trap study. A generalizable model produced from an unbalanced class set can be utilized to extract trap events that can later be confirmed by human processors.

13.
J Med Entomol ; 58(5): 2006-2011, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34342359

RESUMO

Medical Entomology as a field is inherently global - thriving on international and interdisciplinary collaborations and affected dramatically by arthropod and pathogen invasions and introductions. This past year also will be remembered as the year in which the SARS-CoV-2 COVID-19 pandemic affected every part of our lives and professional activities and impacted (or changed, sometimes in good ways) our ability to collaborate and detect or respond to invasions. This incredible year is the backdrop for the 2020 Highlights in Medical Entomology. This article highlights the broad scope of approaches and disciplines represented in the 2020 published literature, ranging from sensory and chemical ecology, population genetics, impacts of human-mediated environmental change on vector ecology, life history and the evolution of vector behaviors, to the latest developments in vector surveillance and control.


Assuntos
Entomologia , Aedes , Animais , COVID-19/epidemiologia , Meio Ambiente , Humanos , Controle de Insetos , Insetos Vetores , Doenças Transmitidas por Carrapatos/epidemiologia , Carrapatos
14.
Orig Life Evol Biosph ; 51(3): 185-213, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34279769

RESUMO

How life arose on the primitive Earth is one of the biggest questions in science. Biomolecular emergence scenarios have proliferated in the literature but accounting for the ubiquity of oxidized (+ 5) phosphate (PO43-) in extant biochemistries has been challenging due to the dearth of phosphate and molecular oxygen on the primordial Earth. A compelling body of work suggests that exogenous schreibersite ((Fe,Ni)3P) was delivered to Earth via meteorite impacts during the Heavy Bombardment (ca. 4.1-3.8 Gya) and there converted to reduced P oxyanions (e.g., phosphite (HPO32-) and hypophosphite (H2PO2-)) and phosphonates. Inspired by this idea, we review the relevant literature to deduce a plausible reduced phospholipid analog of modern phosphatidylcholines that could have emerged in a primordial hydrothermal setting. A shallow alkaline lacustrine basin underlain by active hydrothermal fissures and meteoritic schreibersite-, clay-, and metal-enriched sediments is envisioned. The water column is laden with known and putative primordial hydrothermal reagents. Small system dimensions and thermal- and UV-driven evaporation further concentrate chemical precursors. We hypothesize that a reduced phospholipid arises from Fischer-Tropsch-type (FTT) production of a C8 alkanoic acid, which condenses with an organophosphinate (derived from schreibersite corrosion to hypophosphite with subsequent methylation/oxidation), to yield a reduced protophospholipid. This then condenses with an α-amino nitrile (derived from Strecker-type reactions) to form the polar head. Preliminary modeling results indicate that reduced phospholipids do not aggregate rapidly; however, single layer micelles are stable up to aggregates with approximately 100 molecules.


Assuntos
Meteoroides , Fósforo , Planeta Terra , Fosfatos , Fosfolipídeos
15.
J Med Entomol ; 58(4): 1849-1864, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-33855433

RESUMO

In Illinois, between 1990 and 2017, tick-borne diseases in humans increased 10-fold, yet we have insufficient information on when and where people are exposed to vector ticks (Ixodida: Ixodidae). The aims of our research were to compare contributions of passive and active tick collection methods in determining establishment of ticks of public health concern and obtain information on tick distributions within Illinois. We used three surveillance strategies within the Illinois Tick Inventory Collaboration Network to gather information about the ticks of public health concern: 1) passive collection (voluntary submission by the public); 2) systematic collection (biweekly active surveillance); and 3) special collections (active collections in locations of special interest). Of collected adult and nymphal ticks, 436 were from passive collections, 142 from systematic collections, and 1,270 from special collections. Tick species distribution status changed in 36 counties. Our data provide noteworthy updates to distribution maps for use by public health agencies to develop prevention and control strategies. Additionally, the program built a network of collaborations and partnerships to support future tick surveillance efforts within Illinois and highlighted how the combination of the three surveillance strategies can be used to determine geographic spread of ticks, pinpoint locations in need of more surveillance, and help with long-term efforts that support phenology studies.


Assuntos
Monitoramento Epidemiológico , Ixodidae , Animais , Vetores Aracnídeos , Illinois/epidemiologia , Saúde Pública/métodos , Infestações por Carrapato/epidemiologia , Doenças Transmitidas por Carrapatos/epidemiologia
16.
Front Zool ; 18(1): 10, 2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33750400

RESUMO

BACKGROUND: The yellow fever mosquito, Aedes aegypti, is the principal vector of medically-important infectious viruses that cause severe illness such as dengue fever, yellow fever and Zika. The transmission potential of mosquitoes for these arboviruses is largely shaped by their life history traits, such as size, survival and fecundity. These life history traits, to some degree, depend on environmental conditions, such as larval and adult nutrition (e.g., nectar availability). Both these types of nutrition are known to affect the energetic reserves and life history traits of adults, but whether and how nutrition obtained during larval and adult stages have an interactive influence on mosquito life history traits remains largely unknown. RESULTS: Here, we experimentally manipulated mosquito diets to create two nutritional levels at larval and adult stages, that is, a high or low amount of larval food (HL or LL) during larval stage, and a good and poor adult food (GA or PA, represents normal or weak concentration of sucrose) during adult stage. We then compared the size, survival and fecundity of female mosquitoes reared from these nutritional regimes. We found that larval and adult nutrition affected size and survival, respectively, without interactions, while both larval and adult nutrition influenced fecundity. There was a positive relationship between fecundity and size. In addition, this positive relationship was not affected by nutrition. CONCLUSIONS: These findings highlight how larval and adult nutrition differentially influence female mosquito life history traits, suggesting that studies evaluating nutritional effects on vectorial capacity traits should account for environmental variation across life stages.

17.
Parasit Vectors ; 13(1): 532, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33109276

RESUMO

BACKGROUND: The bacterial communities associated with mosquito eggs are an essential component of the mosquito microbiota, yet there are few studies characterizing and comparing the microbiota of mosquito eggs to other host tissues. METHODS: We sampled gravid female Culex pipiens L. and Culex restuans Theobald from the field, allowed them to oviposit in the laboratory, and characterized the bacterial communities associated with their egg rafts and midguts for comparison through MiSeq sequencing of the 16S rRNA gene. RESULTS: Bacterial richness was higher in egg rafts than in midguts for both species, and higher in Cx pipiens than Cx. restuans. The midgut samples of Cx. pipiens and Cx. restuans were dominated by Providencia. Culex pipiens and Cx. restuans egg rafts samples were dominated by Ralstonia and Novosphingobium, respectively. NMDS ordination based on Bray-Curtis distance matrix revealed that egg-raft samples, or midgut tissues harbored similar bacterial communities regardless of the mosquito species. Within each mosquito species, there was a distinct clustering of bacterial communities between egg raft and midgut tissues. CONCLUSION: These findings expand the list of described bacterial communities associated with Cx. pipiens and Cx. restuans and the additional characterization of the egg raft bacterial communities facilitates comparative analysis of mosquito host tissues, providing a basis for future studies seeking to understand any functional role of the bacterial communities in mosquito biology.


Assuntos
Bactérias , Culex/microbiologia , Animais , Bactérias/classificação , Bactérias/isolamento & purificação , Feminino , Microbioma Gastrointestinal , Genes Bacterianos , Larva/microbiologia , Metagenômica/métodos , Microbiota , Oviposição , RNA Ribossômico 16S/genética
18.
J Med Entomol ; 57(5): 1488-1500, 2020 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-32195543

RESUMO

The spread of the Asian tiger mosquito, Aedes albopictus Skuse, throughout the United States has implications for the transmission potential of vector-borne diseases. We used a 30-yr data set of occurrence records in Illinois and developed a hierarchical Bayesian model to shed light on the patterns and processes involved in the introduction and expansion along the northern edge of the geographic range of this species. We also collected specimens from 10 locations and sequenced a segment of their mitochondrial COI genes to assess possible introduction sources and geographic patterns in genetic variation present within contemporary populations. We documented an increase in the number of observations throughout the southern and central parts of Illinois over the study period. The process through which this spread occurred is likely only partially due to local dispersal. The probability of successfully overwintering was likewise low, but both these parameters increased over the study period. This suggests that the presence of Ae. albopictus has been largely due to repeated introductions, but that in recent years populations may have become established and are leading to an increase in locally driven dispersal. There was considerable genetic diversity among populations in Illinois, with 13 distinct haplotypes present in 10 sampling locations, several of which matched haplotypes previously found to be present in locations such as Texas or Japan. Further research is needed to understand how the combination of continued propagule pressure and establishment of populations are driving the increase and expansion of this invasive mosquito along its northern distribution limit.


Assuntos
Aedes/fisiologia , Distribuição Animal , Variação Genética , Espécies Introduzidas , Aedes/genética , Animais , Complexo IV da Cadeia de Transporte de Elétrons/análise , Feminino , Haplótipos , Illinois , Proteínas de Insetos/análise , Análise de Sequência de DNA , Análise Espaço-Temporal
19.
J Parasitol ; 106(1): 9-13, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31958375

RESUMO

The Gulf Coast tick, Amblyomma maculatum, is of public and veterinary health concern, as it is the primary vector of Rickettsia parkeri and Hepatozoon americanum, causative agents of Rickettsiosis and American canine hepatozoonosis. The Gulf Coast tick's range has expanded over the last 50 yr into the mid-Atlantic states, and its expansion is expected to continue northward. We are reporting the presence of A. maculatum for the first time in Illinois, including a total of 18 specimens collected at 6 different sites during surveys in 2013 and 2019. Fourteen of these specimens were screened for Rickettsia parkeri, which resulted in the detection of this bacteria in 8 samples from 4 counties. By depositing these specimens in scientific collections, we provide materialistic evidence of their establishment in 2 counties. We urge health officials to rely on and use scientific collections to document the expansion of these and other vectors across the country. Additionally, we recommend that health practitioners become aware of the clinical similarities between Rocky Mountain Spotted Fever (caused by Rickettsia rickettsii) and "tidewater" fever (caused by R. parkeri).


Assuntos
Vetores Aracnídeos/fisiologia , Ixodidae/fisiologia , Infecções por Rickettsia/transmissão , Rickettsia/fisiologia , Animais , Vetores Aracnídeos/anatomia & histologia , Vetores Aracnídeos/microbiologia , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/isolamento & purificação , DNA Bacteriano/análise , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , Feminino , Illinois , Ixodidae/anatomia & histologia , Ixodidae/microbiologia , Masculino , Reação em Cadeia da Polimerase em Tempo Real , Rickettsia/genética , Rickettsia/isolamento & purificação , Infecções por Rickettsia/microbiologia
20.
J Theor Biol ; 490: 110161, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-31953137

RESUMO

Effective public health measures must balance potentially conflicting demands from populations they serve. In the case of infectious disease risks from mosquito-borne infections, such as Zika virus, public concern about the pathogen may be counterbalanced by public concern about environmental contamination from chemical agents used for vector control. Here we introduce a generic framework for modeling how the spread of an infectious pathogen might lead to varying public perceptions, and therefore tolerance, of both disease risk and pesticide use. We consider how these dynamics might impact the spread of a vector-borne disease. We tailor and parameterize our model for direct application to Zika virus as spread by Aedes aegypti mosquitoes, though the framework itself has broad applicability to any arboviral infection. We demonstrate how public risk perception of both disease and pesticides may drastically impact the spread of a mosquito-borne disease in a susceptible population. We conclude that models hoping to inform public health decision making about how best to mitigate arboviral disease risks should explicitly consider the potential public demand for, or rejection of, chemical control of mosquito populations.


Assuntos
Aedes , Infecções por Arbovirus , Infecção por Zika virus , Zika virus , Animais , Infecções por Arbovirus/epidemiologia , Mosquitos Vetores , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/prevenção & controle
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