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1.
Parasit Vectors ; 17(1): 187, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605410

RESUMO

BACKGROUND: In the context of climate change, a growing concern is that vector-pathogen or host-parasite interactions may be correlated with climatic factors, especially increasing temperatures. In the present study, we used a mosquito-microsporidian model to determine the impact of environmental factors such as temperature, humidity, wind and rainfall on the occurrence rates of opportunistic obligate microparasites (Microsporidia) in hosts from a family that includes important disease vectors (Culicidae). METHODS: In our study, 3000 adult mosquitoes collected from the field over 3 years were analysed. Mosquitoes and microsporidia were identified using PCR and sequencing of the hypervariable V5 region of the small subunit ribosomal RNA gene and a shortened fragment of the cytochrome c oxidase subunit I gene, respectively. RESULTS: DNA metabarcoding was used to identify nine mosquito species, all of which were hosts of 12 microsporidian species. The prevalence of microsporidian DNA across all mosquito samples was 34.6%. Microsporidian prevalence in mosquitoes was more frequent during warm months (> 19 °C; humidity < 65%), as was the co-occurrence of two or three microsporidian species in a single host individual. During warm months, microsporidian occurrence was noted 1.6-fold more often than during the cold periods. Among the microsporidians found in the mosquitoes, five (representing the genera Enterocytospora, Vairimorpha and Microsporidium) were positively correlated with an increase in temperature, whereas one (Hazardia sp.) was significantly correlated with a decrease in temperature. Threefold more microsporidian co-occurrences were recorded in the warm months than in the cold months. CONCLUSIONS: These results suggest that the susceptibility of mosquitoes to parasite occurrence is primarily determined by environmental conditions, such as, for example, temperatures > 19 °C and humidity not exceeding 62%. Collectively, our data provide a better understanding of the effects of the environment on microsporidian-mosquito interactions.


Assuntos
Culicidae , Microsporídios , Animais , Culicidae/parasitologia , Temperatura , Umidade , Mosquitos Vetores , Microsporídios/genética , DNA
2.
BMC Res Notes ; 17(1): 98, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38561830

RESUMO

INTRODUCTION: Dermatobia hominis belongs to the Cuterebridae family, Diptera order; These flies inhabit tropical regions where they are called "fly of death" since the larvae are capable of causing lesions in domestic animals, wild animals including humans, the adult females of D. hominis capture other dipteran to oviposit their eggs on them (phoresis), when hematophagous mosquitoes land on an animal and / or human in order to feed on their blood, the eggs hatch and the larvae immediately penetrate the skin where they will develop to later abandon the host, then in the soil and / or other moist substrate the pupal stage develops, finally new adult flies will emerge from the pupae. OBJECTIVE: The primary goal of the present study was to determine as first record, the presence of Psorophora ferox infested with eggs of Dermatobia hominis, Peru. METHODOLOGY: The present study was carried out in an area of the private reserve "El Vencedor", located within the city of Pucallpa, Ucayali Region-Perú. The area is characterized by being humid tropical, with an average temperature of 26ºC and humidity of 92%, while the annual precipitation is approximately 1570 mm3. The capture method was carried out with the help of a hand net type "butterfly" or also called Jama. RESULTS: A total of 668 mosquitoes of different species were collected, the most abundant being Psorophora albigenu and Psorophora ferox, which represented 88.72% and the least abundant was Culex coronator and Uranotaenia apicalis with 0.15% of the total sample collected. CONCLUSIONS: Within these specimens it was captured a mosquito of the species Ps. ferox with the presence of 8 eggs of D. hominis, of which 3 would have hatched, while in the remaining 5, the larvae would remain inside the eggs.


Assuntos
Culicidae , Dípteros , Animais , Feminino , Adulto , Humanos , Peru , Larva , Pele , Pupa
3.
Curr Biol ; 34(7): R291-R293, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38593776

RESUMO

Some insects have a frustrating knack for avoiding a swatter. A new study shows that mosquitos not only evade the visual image of the looming threat, they also surf the wave of air the swatter creates.


Assuntos
Culicidae , Animais , Comportamento Animal , Voo Animal
4.
Parasit Vectors ; 17(1): 168, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566167

RESUMO

BACKGROUND: Mosquitoes inhabiting urban green spaces and cemeteries in Europe represent a crucial facet of public health concern and contribute to the ecological balance. As urbanization intensifies, these areas increasingly serve as vital habitats for various mosquito species, fostering breeding grounds and increasing the risk of disease transmission. METHODS: A study was conducted in the three main cities (inland, coastal, and estuarine) of the Basque Country, northern Spain, to investigate the species composition, abundance, dynamic populations, larval habitats, and host preferences of mosquitoes in urban green spaces and cemeteries. CDC traps and dipping were used to collect mosquitoes for 2 years (2019-2020). RESULTS: A total of 21 mosquito species were identified, with Culex pipiens s.l. being the most abundant and widespread. The three ecological forms of Cx. pipiens were found, and Cx. pipiens pipiens was the most common in both green areas and cemeteries. Morphological identification together with molecular tools identified 65 COI sequences with high homology. The highest species richness was found in the inland city, followed by the coastal city and the estuarine city. Mosquito abundance was significantly higher in green areas compared to cemeteries and in the coastal and estuarine cities compared to the inland city. The investigation of larval breeding sites highlighted the dominance of Cx. pipiens s.l., particularly in semi-artificial ponds, diverse water-holding containers (tyres and buckets) and drainage systems in green areas; in cemeteries, most of the larvae were found in flowerpots and funerary urns. Seasonal activity exhibited variable peaks in mosquito abundance in the different cities, with a notable increase in July or August. Additionally, blood meal analysis revealed that Cx. pipiens s.l. fed on several common urban avian species. CONCLUSIONS: Studies on mosquitoes are essential to understand their role in disease transmission and to design targeted and sustainable management strategies to mitigate the associated risks.


Assuntos
Culex , Culicidae , Animais , Espanha , Parques Recreativos , Cemitérios , Culex/anatomia & histologia , Larva
5.
BMC Vet Res ; 20(1): 149, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643105

RESUMO

This research work was planned to test biosafety of different nanomaterials on the different animals models. These nanoparticles were previously used as potential insecticides of mosquito larvae. The biosafety of these nanoproducts were evaluated on certain organs of non target animals that associated with mosquito breeding sites in Egypt. Animal organs such as the kidneys of rats, toads, and the fish's spleen were used as models to study the biological toxicity of these nanomaterials. After 30 days of the animals receiving the nanomaterials in their water supply, different cell mediated immune cells were assessed in these tissues. Both TNF-α and BAX immuno-expression were also used as immunohistochemical markers. Histopathology was conducted to detect the effect of the tested nanoproducts at the tissue level of the liver and kidneys of both the rats and toads. Green nanoemulsion of the lavender essential oil was relatively more effective, safe, and biodegradable to be used as insecticides against mosquito larvae than the metal-based nanomaterials.


Assuntos
Culicidae , Inseticidas , Nanopartículas Metálicas , Ratos , Animais , Inseticidas/toxicidade , Prata/farmacologia , Melhoramento Vegetal , Larva , Emulsões
6.
PLoS One ; 19(4): e0298451, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635576

RESUMO

The paper presents an innovative computational framework for predictive solutions for simulating the spread of malaria. The structure incorporates sophisticated computing methods to improve the reliability of predicting malaria outbreaks. The study strives to provide a strong and effective tool for forecasting the propagation of malaria via the use of an AI-based recurrent neural network (RNN). The model is classified into two groups, consisting of humans and mosquitoes. To develop the model, the traditional Ross-Macdonald model is expanded upon, allowing for a more comprehensive analysis of the intricate dynamics at play. To gain a deeper understanding of the extended Ross model, we employ RNN, treating it as an initial value problem involving a system of first-order ordinary differential equations, each representing one of the seven profiles. This method enables us to obtain valuable insights and elucidate the complexities inherent in the propagation of malaria. Mosquitoes and humans constitute the two cohorts encompassed within the exposition of the mathematical dynamical model. Human dynamics are comprised of individuals who are susceptible, exposed, infectious, and in recovery. The mosquito population, on the other hand, is divided into three categories: susceptible, exposed, and infected. For RNN, we used the input of 0 to 300 days with an interval length of 3 days. The evaluation of the precision and accuracy of the methodology is conducted by superimposing the estimated solution onto the numerical solution. In addition, the outcomes obtained from the RNN are examined, including regression analysis, assessment of error autocorrelation, examination of time series response plots, mean square error, error histogram, and absolute error. A reduced mean square error signifies that the model's estimates are more accurate. The result is consistent with acquiring an approximate absolute error close to zero, revealing the efficacy of the suggested strategy. This research presents a novel approach to solving the malaria propagation model using recurrent neural networks. Additionally, it examines the behavior of various profiles under varying initial conditions of the malaria propagation model, which consists of a system of ordinary differential equations.


Assuntos
Culicidae , Malária , Animais , Humanos , Reprodutibilidade dos Testes , Redes Neurais de Computação , Malária/epidemiologia , Modelos Teóricos
7.
Malar J ; 23(1): 111, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641838

RESUMO

BACKGROUND: Sporozoites (SPZ), the infective form of Plasmodium falciparum malaria, can be inoculated into the human host skin by Anopheline mosquitoes. These SPZ migrate at approximately 1 µm/s to find a blood vessel and travel to the liver where they infect hepatocytes and multiply. In the skin they are still low in number (50-100 SPZ) and vulnerable to immune attack by antibodies and skin macrophages. This is why whole SPZ and SPZ proteins are used as the basis for most malaria vaccines currently deployed and undergoing late clinical testing. Mosquitoes typically inoculate SPZ into a human host between 14 and 25 days after their previous infective blood meal. However, it is unknown whether residing time within the mosquito affects SPZ condition, infectivity or immunogenicity. This study aimed to unravel how the age of P. falciparum SPZ in salivary glands (14, 17, or 20 days post blood meal) affects their infectivity and the ensuing immune responses. METHODS: SPZ numbers, viability by live/dead staining, motility using dedicated sporozoite motility orienting and organizing tool software (SMOOT), and infectivity of HC-04.j7 liver cells at 14, 17 and 20 days after mosquito feeding have been investigated. In vitro co-culture assays with SPZ stimulated monocyte-derived macrophages (MoMɸ) and CD8+ T-cells, analysed by flow cytometry, were used to investigate immune responses. RESULTS: SPZ age did not result in different SPZ numbers or viability. However, a markedly different motility pattern, whereby motility decreased from 89% at day 14 to 80% at day 17 and 71% at day 20 was observed (p ≤ 0.0001). Similarly, infectivity of day 20 SPZ dropped to ~ 50% compared with day 14 SPZ (p = 0.004). MoMɸ were better able to take up day 14 SPZ than day 20 SPZ (from 7.6% to 4.1%, p = 0.03) and displayed an increased expression of pro-inflammatory CD80, IL-6 (p = 0.005), regulatory markers PDL1 (p = 0.02), IL-10 (p = 0.009) and cytokines upon phagocytosis of younger SPZ. Interestingly, co-culture of these cells with CD8+ T-cells revealed a decreased expression of activation marker CD137 and cytokine IFNγ compared to their day 20 counterparts. These findings suggest that older (day 17-20) P. falciparum SPZ are less infectious and have decreased immune regulatory potential. CONCLUSION: Overall, this data is a first step in enhancing the understanding of how mosquito residing time affects P. falciparum SPZ and could impact the understanding of the P. falciparum infectious reservoir and the potency of whole SPZ vaccines.


Assuntos
Culicidae , Vacinas Antimaláricas , Malária Falciparum , Animais , Humanos , Esporozoítos , Linfócitos T CD8-Positivos , Envelhecimento , Plasmodium falciparum
8.
Infect Dis Poverty ; 13(1): 29, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622750

RESUMO

BACKGROUND: Culex pipiens pallens and Culex pipiens quinquefasciatus are the dominant species of Culex mosquitoes in China and important disease vectors. Long-term use of insecticides can cause mutations in the voltage-gated sodium channel (vgsc) gene of mosquitoes, but little is known about the current status and evolutionary origins of vgsc gene in different geographic populations. Therefore, this study aimed to determine the current status of vgsc genes in Cx. p. pallens and Cx. p. quinquefasciatus in China and to investigate the evolutionary inheritance of neighboring downstream introns of the vgsc gene to determine the impact of insecticides on long-term evolution. METHODS: Sampling was conducted from July to September 2021 in representative habitats of 22 provincial-level administrative divisions in China. Genomic DNA was extracted from 1308 mosquitoes, the IIS6 fragment of the vgsc gene on the nerve cell membrane was amplified using polymerase chain reaction, and the sequence was used to evaluate allele frequency and knockdown resistance (kdr) frequency. MEGA 11 was used to construct neighbor-joining (NJ) tree. PopART was used to build a TCS network. RESULTS: There were 6 alleles and 6 genotypes at the L1014 locus, which included the wild-type alleles TTA/L and CTA/L and the mutant alleles TTT/F, TTC/F, TCT/S and TCA/S. The geographic populations with a kdr frequency less than 20.00% were mainly concentrated in the regions north of 38° N, and the geographic populations with a kdr frequency greater than 80.00% were concentrated in the regions south of 30° N. kdr frequency increased with decreasing latitude. And within the same latitude, the frequency of kdr in large cities is relatively high. Mutations were correlated with the number of introns. The mutant allele TCA/S has only one intron, the mutant allele TTT/F has three introns, and the wild-type allele TTA/L has 17 introns. CONCLUSIONS: Cx. p. pallens and Cx. p. quinquefasciatus have developed resistance to insecticides in most regions of China. The neighboring downstream introns of the vgsc gene gradually decreased to one intron with the mutation of the vgsc gene. Mutations may originate from multiple mutation events rather than from a single origin, and populations lacking mutations may be genetically isolated.


Assuntos
Culex , Culicidae , Inseticidas , Piretrinas , Canais de Sódio Disparados por Voltagem , Animais , Inseticidas/farmacologia , Íntrons/genética , Mosquitos Vetores/genética , Culex/genética , Mutação , Canais de Sódio Disparados por Voltagem/genética , Resistência a Inseticidas/genética
9.
Artigo em Chinês | MEDLINE | ID: mdl-38604685

RESUMO

OBJECTIVE: To investigate the microbiota composition and diversity between autogenous and anautogenous Culex pipiens pallens, so as to provide insights into unraveling the pathogenesis of autogeny in Cx. pipiens pallens. METHODS: Autogenous and anautogenous adult Cx. pipiens pallens samples were collected at 25 ℃, and the hypervariable regions of the microbial 16S ribosomal RNA (16S rRNA) gene was sequenced on the Illumina NovaSeq 6000 sequencing platform. The microbiota abundance and diversity were evaluated using the alpha diversity index, and the difference in the microbiota structure was examined using the beta diversity index. The microbiota with significant differences in the abundance between autogenous and anautogenous adult Cx. pipiens pallens samples was identified using the linear discriminant analysis effect size (LEfSe). RESULTS: The microbiota in autogenous and anautogenous Cx. pipiens pallens samples belonged to 18 phyla, 28 classes, 70 orders, 113 families, and 170 genera, and the dominant phyla included Proteobacteria, Bacteroidetes, and so on. At the genus level, Wolbachia was a common dominant genus, and the relative abundance was (77.6 ± 11.3)% in autogenous Cx. pipiens pallens samples and (47.5 ± 8.5)% in anautogenous mosquito samples, while Faecalibaculum (0.4% ± 0.1%), Dubosiella (0.5% ± 0.0%) and Massilia (0.5% ± 0.1%) were specific species in autogenous Cx. pipiens pallens samples. Alpha diversity analysis showed that higher Chao1 index and ACE index in autogenous Cx. pipiens pallens samples than in anautogenous samples (both P values > 0.05), and lower Shannon index (P > 0.05) and Simpson index (P < 0.05) in autogenous Cx. pipiens pallens samples than in anautogenous samples. LEfSe analysis showed a total of 48 significantly different taxa between autogenous and anautogenous Cx. pipiens pallens samples (all P values < 0.05). CONCLUSIONS: There is a significant difference in the microbiota diversity between autogenous and anautogenous Cx. pipiens pallens.


Assuntos
Culex , Culicidae , Microbiota , Humanos , Animais , RNA Ribossômico 16S/genética , Culex/genética , Culicidae/genética , Microbiota/genética
10.
Pestic Biochem Physiol ; 200: 105809, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38582581

RESUMO

Culex quinquefasciatus is the main vector of lymphatic filariasis in Brazil, which present resistance to commercial insecticides. Nowadays, essential oils (EOs) exhibiting larvicidal activity, such as those derived from Piper alatipetiolatum, provide a promising alternative for vector control, including Culex species. This study aimed to investigate the larvicidal activity and the oxidative stress indicators of the EO from P. alatipetiolatum in Cx. quinquefasciatus larvae. The EO was extracted from P. alatipetiolatum leaves using the hydrodistillation method, resulting in a yield of 7.2 ± 0.1%, analysed by gas chromatography coupled with spectrometry and gas chromatography coupled with flame ionization detector (GC-MS and GC-FID), and evaluated against Cx. quinquefasciatus larvae. Reactive Oxygen and Nitrogen Species (RONS), Catalase (CAT), glutathione-S-transferase (GST), acetylcholinesterase (AChE), and Thiol levels were used as oxidative stress indicators. Analysis by CG-MS and CG-FID revealed that the main compound in the EO was the oxygenated sesquiterpene ishwarone, constituting 78.6% of the composition. Furthermore, the EO exhibited larvicidal activity, ranging from 26 to 100%, with an LC50 of 4.53 µg/mL and LC90 of 15.37 µg/mL. This activity was accompanied by a significant increase in RONS production, alterations in CAT, GST, AChE activity, and thiol levels compared to the control groups (p < 0.05). To the best of our knowledge, this is the first report describing the larvicidal activity and oxidative stress induced by the EO from P. alatipetiolatum against Cx. quinquefasciatus larvae. Therefore, we propose that this EO shows promise as larvicidal agent for the effective control of Cx. quinquefasciatus larvae.


Assuntos
Aedes , Culex , Culicidae , Inseticidas , Óleos Voláteis , Piper , Animais , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Larva , Acetilcolinesterase , Mosquitos Vetores , Inseticidas/farmacologia , Inseticidas/química , Compostos de Sulfidrila/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta
11.
G Ital Nefrol ; 41(1)2024 Feb 28.
Artigo em Italiano | MEDLINE | ID: mdl-38426678

RESUMO

The West Nile Virus (WNV), an RNA arbovirus, has been transmitted by wild birds and conveyed by ticks and mosquitoes, with wide diffusion all over the world; it is not transmitted from human to human. It can give clinical symptoms only in a minority of infected subjects such as fever, headache, muscle tiredness, visual disturbances, drowsiness, convulsions and muscle paralysis; in the most serious cases even potentially fatal encephalitis. In the literature there are few reports on WNV infection in patients with kidney diseases: here we report our experience on two patients on peritoneal dialysis infected by WNV with a revision of the literature.


Assuntos
Culicidae , Nefropatias , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Humanos , Febre do Nilo Ocidental/complicações , Febre do Nilo Ocidental/diagnóstico , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/genética , Aves
12.
Parasit Vectors ; 17(1): 136, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491527

RESUMO

BACKGROUND: Maintaining mosquito colonies in the laboratory requires a blood supply so that females' oocytes can mature and oviposition can take place. In this study, a new artificial hematophagy system for colonization and maintenance of Culex quinquefasciatus in the laboratory was developed and tested. METHODS: We developed an attractive polymeric biofilm including 25% L-lactic acid for use as a membrane in an artificial hematophagy system and compared the feeding rate of females with Parafilm-M®. We also evaluated the oviposition rate, larval survival and adult emergence of females fed through the attractive biofilm. RESULTS: The average percentage of female Cx. quinquefasciatus fed through the attractive biofilm was 87%, while only 20% became engorged with Parafilm-M® (p < 0.0001). Feeding through the attractive biofilm developed in this study produced high levels of evaluated biological parameters; the percentage of egg laying by females that underwent artificial hematophagy through the biofilm was 90%, with an average of 158 eggs per raft. From these eggs, 97% of the larvae hatched, of which 95% reached the pupal stage. The adult emergence rate corresponded to 93% of pupae. CONCLUSIONS: Insects fed with attractant through the biofilm system had a higher engorgement rate compared to those fed through Parafilm-M®. Our study is preliminary and suggests that polymeric biofilm has great potential for artificially feeding mosquitoes in the laboratory. Based on this research, new studies will be carried out with biofilm and different systems.


Assuntos
Culex , Culicidae , Feminino , Animais , Parafina , Óvulo , Oviposição , Larva
13.
Trends Parasitol ; 40(4): 302-312, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38443304

RESUMO

Malaria parasites have coevolved with humans over thousands of years, mirroring their migration out of Africa. They persist to this day, despite continuous elimination efforts worldwide. These parasites can adapt to changing environments during infection of human and mosquito, and when expanding the geographical range by switching vector species. Recent studies in the human malaria parasite, Plasmodium falciparum, identified determinants governing the plasticity of sexual conversion rates, sex ratio, and vector competence. Here we summarize the latest literature revealing environmental, epigenetic, and genetic determinants of malaria transmission.


Assuntos
Culicidae , Malária Falciparum , Malária , Animais , Humanos , Malária Falciparum/parasitologia , Mosquitos Vetores , Malária/parasitologia , Plasmodium falciparum/genética , Culicidae/parasitologia
14.
Sci Rep ; 14(1): 7432, 2024 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548880

RESUMO

Mosquitoes (Culicidae) represent the main vector insects globally, and they also inhabit many of the terrestrial and aquatic habitats of the world. DNA barcoding and metabarcoding are now widely used in both research and routine practices involving mosquitoes. However, these methodologies rely on information available in databases consisting of barcode sequences representing taxonomically identified voucher specimens. In this study, we assess the availability of public data for mosquitoes in the main online databases, focusing specifically on the two most widely used DNA barcoding markers in Culicidae: COI and ITS2. In addition, we test hypotheses on possible factors affecting species coverage (i.e., the percentage of species covered in the online databases) for COI in different countries and the occurrence of the DNA barcode gap for COI. Our findings showed differences in the data publicly available in the repositories, with a taxonomic or species coverage of 28.4-30.11% for COI in BOLD + GenBank, and 12.32% for ITS2 in GenBank. Afrotropical, Australian and Oriental biogeographic regions had the lowest coverages, while Nearctic, Palearctic and Oceanian had the highest. The Neotropical region had an intermediate coverage. In general, countries with a higher diversity of mosquitoes and higher numbers of medically important species had lower coverage. Moreover, countries with a higher number of endemic species tended to have a higher coverage. Although our DNA barcode gap analyses suggested that the species boundaries need to be revised in half of the mosquito species available in the databases, additional data must be gathered to confirm these results and to allow explaining the occurrence of the DNA barcode gap. We hope this study can help guide regional species inventories of mosquitoes and the completion of a publicly available reference library of DNA barcodes for all mosquito species.


Assuntos
Culicidae , Animais , Culicidae/genética , Código de Barras de DNA Taxonômico/métodos , Mosquitos Vetores , Austrália , DNA/genética , Biodiversidade
15.
Virulence ; 15(1): 2329447, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38548679

RESUMO

MicroRNAs (miRNAs) are small non-coding RNAs that regulate the post-transcriptional expression of target genes. Virus-encoded miRNAs play an important role in the replication of viruses, modulate gene expression in both the virus and host, and affect their persistence and immune evasion in hosts. This renders viral miRNAs as potential targets for therapeutic applications, especially against pathogenic viruses that infect humans and animals. Rift Valley fever virus (RVFV) is a mosquito-borne zoonotic RNA virus that causes severe disease in both humans and livestock. High mortality among newborn lambs and abortion storms are key characteristics of an RVF outbreak. To date, limited information is available on RVFV-derived miRNAs. In this study, computational methods were used to analyse the RVFV genome for putative pre-miRNA genes, which were then analysed for the presence of mature miRNAs. We detected 19 RVFV-encoded miRNAs and identified their potential mRNAs targets in sheep (Ovis aries), the most susceptible host. The identification of significantly enriched O. aries genes in association with RVFV miRNAs will help elucidate the molecular mechanisms underlying RVFV pathogenesis and potentially uncover novel drug targets for RVFV.


Assuntos
Culicidae , MicroRNAs , Febre do Vale de Rift , Vírus da Febre do Vale do Rift , Humanos , Gravidez , Feminino , Animais , Ovinos/genética , Vírus da Febre do Vale do Rift/genética , Febre do Vale de Rift/genética , Febre do Vale de Rift/epidemiologia , Culicidae/genética , Surtos de Doenças , MicroRNAs/genética
16.
Mol Ecol ; 33(7): e17314, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38441172

RESUMO

Understanding microbial roles in ecosystem function requires integrating microscopic processes into food webs. The carnivorous pitcher plant, Sarracenia purpurea, offers a tractable study system where diverse food webs of macroinvertebrates and microbes facilitate digestion of captured insect prey, releasing nutrients supporting the food web and host plant. However, how interactions between these macroinvertebrate and microbial communities contribute to ecosystem functions remains unclear. We examined the role of the pitcher plant mosquito, Wyeomyia smithii, in top-down control of the composition and function of pitcher plant microbial communities. Mosquito larval abundance was enriched or depleted across a natural population of S. purpurea pitchers over a 74-day field experiment. Bacterial community composition and microbial community function were characterized by 16S rRNA amplicon sequencing and profiling of carbon substrate use, bulk metabolic rate, hydrolytic enzyme activity, and macronutrient pools. Bacterial communities changed from pitcher opening to maturation, but larvae exerted minor effects on high-level taxonomic composition. Higher larval abundance was associated with lower diversity communities with distinct functions and elevated nitrogen availability. Treatment-independent clustering also supported roles for larvae in curating pitcher microbial communities through shifts in community diversity and function. These results demonstrate top-down control of microbial functions in an aquatic microecosystem.


Assuntos
Culicidae , Microbiota , Animais , Culicidae/genética , RNA Ribossômico 16S/genética , Cadeia Alimentar , Insetos/genética , Larva , Bactérias/genética , Microbiota/genética
17.
Vector Borne Zoonotic Dis ; 24(4): 245-248, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38441490

RESUMO

Japanese encephalitis virus is mainly prevalent in the tropical and subtropical regions of Asia and Oceania. Through immunoprecipitation-mass spectrometry analysis using monoclonal antibodies targeting JEV E protein, we found that mosquito Histone 2A protein could bind to JEV particles. The binding of H2A and JEV was detected in the salivary gland and supernatant of mosquito cells. Furthermore, RNA interference experiments in vitro and in vivo confirmed that H2A protein promotes JEV infection in mosquitoes. In summary, we found that mosquito H2A is a factor that supports JEV infection and can potentially facilitate cross-species transmission of JEV.


Assuntos
Culex , Culicidae , Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Animais , Vírus da Encefalite Japonesa (Espécie)/genética , Histonas , Encefalite Japonesa/veterinária , Mosquitos Vetores
18.
Zootaxa ; 5406(2): 253-287, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38480153

RESUMO

Female mosquitoes of the genus Sabethes Robineau-Desvoidy, 1827 are implicated in the transmission of several arboviruses, including yellow fever virus. Here, we present an illustrated species identification key for females of the genus Sabethes recorded in Brazil, except Sa. nitidus Theobald, 1901 and Sa. harbachi Nascimento-Pereira, Guimares, Loureno-de-Oliveira & Motta, 2021 as only the males of these species are known. The key is available in dichotomous and interactive formats. An updated list of the Sabethes species of Brazil and new occurrence records for the states of the country are provided. The type localities of four speciesSa. glaucodaemon (Dyar & Shannon, 1925), Sa. amazonicus Gordon & Evans, 1922, Sa. belisarioi Neiva, 1908 and Sa. soperi Lane & Cerqueira, 1942are corrected or restricted.


Assuntos
Culicidae , Dípteros , Masculino , Feminino , Animais , Brasil
19.
Zootaxa ; 5415(4): 577-584, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38480180

RESUMO

Theobaldia indica Edwards, 1920, classified as a subspecies of Culiseta (Culiseta) alaskaensis (Ludlow, 1906), was recently restored to its original species status, as Culiseta (Culiseta) indica (Edwards), based on comprehensive assessments of morphological, ecological and distributional data. Predating the recognition of indica as a separate species, we collected specimens of this nominal taxon in the Western Himalayan region of India during 20152017, and used morphological and molecular studies to assess its taxonomic status. Our detailed examination of adult morphology, male genitalia and larval characteristics revealed significant distinctions between putative Cs. alaskaensis alaskaensis and Cs. alaskaensis indica, and sequencing of the barcode region of the mitochondrial COI gene yielded a Kimura 2 parameter genetic distance of 5.9% between them, well above the standard 23% commonly accepted to indicate separate species. These results strongly support the formal recognition of Cs. indica as a separate species. Furthermore, the geographical distribution of Cs. indica provides additional evidence in support of its species status.


Assuntos
Culicidae , Masculino , Animais , Análise de Sequência de DNA , Larva , Filogenia
20.
Zootaxa ; 5424(1): 139-144, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38480294
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