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1.
Insects ; 15(3)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38535401

RESUMO

The emergence of insecticide resistance in arbovirus vectors is putting the focus on the development of new strategies for control. In this regard, the exploitation of Wolbachia endosymbionts is receiving increasing attention due to its demonstrated effectiveness in reducing the vectorial capacity of Aedes mosquitoes. Here, we describe the establishment of a naïve Wolbachia infection in a wild Aedes albopictus population of eastern Spain through a hybridization approach to obtain males capable of sterilizing wild females. The obtained lines were compared with the Wolbachia donor, Ae. albopictus ARwP, previously artificially infected with Wolbachia wPip, regarding immature and adult survival, female fecundity, egg fertility, and level of induced sterility. Our results did not show significant differences between lines in any of the biological parameters analyzed, indicating the full suitability of the hybrids to be used as a control tool against Ae. albopictus. In particular, hybrid males induced 99.9% sterility in the eggs of wild females without the need for any preliminary treatment. Being harmless to non-target organisms and the environment, the use of this bacterium for the control of Ae. albopictus deserves further exploration. This is especially relevant in areas such as eastern Spain, where this mosquito species has recently spread and may represent a serious threat due to its competence as a vector for dengue, chikungunya, and Zika viruses.

2.
J Feline Med Surg ; 25(12): 1098612X231211763, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38055304

RESUMO

OBJECTIVES: The objectives of this study were to investigate the c.1024G>T SNP in the TRPV4 gene in Scottish Straight and Fold cats, and to evaluate the pattern of skeletal phenotype and the evolution of radiological signs of Scottish Fold osteochondrodysplasia (SFOCD) over time in heterozygous subjects. METHODS: DNA was obtained from blood samples of 17 cats (Scottish Fold: n = 12; Scottish Straight: n = 5) and subsequently genotyped by sequencing in a 249 bp region of the TRPV4 gene (exon 6), including the known c.1024G>T causative mutation for osteochondrodysplasia. Orthopaedic and radiographic analyses were performed on animals carrying the mutant allele. RESULTS: Genotyping by sequencing confirmed that all and only the Scottish Fold cats carried the mutant allele in a heterozygous asset. Furthermore, two other exon variants, already described in the literature as silent variants, were found in some of the sampled cats. Comparative orthogonal radiographic views of the shoulder, elbow, carpus, hip, stifle and tarsus were obtained. A mediolateral projection of the thoracic and lumbar column was also performed. Three out of four cats were clinically and radiographically examined again 1.5 years later. CONCLUSIONS AND RELEVANCE: Although the presence of the mutant allele in all the tested Scottish Fold cats was confirmed, only 1/12 showed clinical signs of SFOCD. Furthermore, no cats in the 1.5-year follow-up showed skeletal changes. Although significant, the c.1024G>T mutation in the TRPV4 gene, supposedly, is not the only cause or risk of developing SFOCD.


Assuntos
Doenças do Gato , Osteocondrodisplasias , Gatos , Animais , Osteocondrodisplasias/diagnóstico por imagem , Osteocondrodisplasias/genética , Osteocondrodisplasias/veterinária , Canais de Cátion TRPV/genética , Região Lombossacral , Mutação , Escócia , Doenças do Gato/diagnóstico por imagem , Doenças do Gato/genética
3.
Phys Life Rev ; 46: 220-244, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37499620

RESUMO

Psychology and neuroscience are concerned with the study of behavior, of internal cognitive processes, and their neural foundations. However, most laboratory studies use constrained experimental settings that greatly limit the range of behaviors that can be expressed. While focusing on restricted settings ensures methodological control, it risks impoverishing the object of study: by restricting behavior, we might miss key aspects of cognitive and neural functions. In this article, we argue that psychology and neuroscience should increasingly adopt innovative experimental designs, measurement methods, analysis techniques and sophisticated computational models to probe rich, ecologically valid forms of behavior, including social behavior. We discuss the challenges of studying rich forms of behavior as well as the novel opportunities offered by state-of-the-art methodologies and new sensing technologies, and we highlight the importance of developing sophisticated formal models. We exemplify our arguments by reviewing some recent streams of research in psychology, neuroscience and other fields (e.g., sports analytics, ethology and robotics) that have addressed rich forms of behavior in a model-based manner. We hope that these "success cases" will encourage psychologists and neuroscientists to extend their toolbox of techniques with sophisticated behavioral models - and to use them to study rich forms of behavior as well as the cognitive and neural processes that they engage.


Assuntos
Neurociências , Projetos de Pesquisa , Comportamento Social , Etologia/métodos , Neurociências/métodos , Dissidências e Disputas
4.
Artigo em Inglês | MEDLINE | ID: mdl-37279127

RESUMO

The article considers a large class of delayed neural networks (NNs) with extended memristors obeying the Stanford model. This is a widely used and popular model that accurately describes the switching dynamics of real nonvolatile memristor devices implemented in nanotechnology. The article studies via the Lyapunov method complete stability (CS), i.e., convergence of trajectories in the presence of multiple equilibrium points (EPs), for delayed NNs with Stanford memristors. The obtained conditions for CS are robust with respect to variations of the interconnections and they hold for any value of the concentrated delay. Moreover, they can be checked either numerically, via a linear matrix inequality (LMI), or analytically, via the concept of Lyapunov diagonally stable (LDS) matrices. The conditions ensure that at the end of the transient capacitor voltages and NN power vanish. In turn, this leads to advantages in terms of power consumption. This notwithstanding, the nonvolatile memristors can retain the result of computation in accordance with the in-memory computing principle. The results are verified and illustrated via numerical simulations. From a methodological viewpoint, the article faces new challenges to prove CS since due to the presence of nonvolatile memristors the NNs possess a continuum of nonisolated EPs. Also, for physical reasons, the memristor state variables are constrained to lie in some given intervals so that the dynamics of the NNs need to be modeled via a class of differential inclusions named differential variational inequalities.

5.
Pest Manag Sci ; 79(9): 3167-3176, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37022600

RESUMO

BACKGROUND: Incompatible insect technique (IIT) is a population suppression approach based on the release of males with manipulated Wolbachia infection inducing egg inviability in wild females. We here present results of multiple field releases of incompatible ARwP males carried out in 2019 in a 2.7-ha green area within urban Rome (Italy) to assess the effect on Aedes albopictus egg viability. Data are compared with results obtained in 2018, when the approach was tested for the first time in Europe. RESULTS: An average of 4674 ARwP males were released weekly for 7 weeks, resulting in a mean ARwP:wild male ratio of 1.1:1 (versus 0.7:1 in 2018). Egg-viability dynamics in ovitraps significantly varied between treated and control sites, with an estimated overall reduction of 35% (versus 15% in 2018). The estimated proportion of females classified as mated with ARwP males was 41.8% and the viability rate of eggs laid by these females (9.5%) was on average significantly lower than that of females only mated with wild males (87.8%); however, high variability in fertility was observed. Values of ARwP male competitiveness were 0.36 and 0.73 based on the overall viability rate of eggs in ovitraps and on female fertility, respectively; thus, well above the conventional 0.2 threshold for an effective suppressive impact in the field. CONCLUSIONS: Results further support the potential of IIT as a tool to contribute to Ae. albopictus control in the urban context, stressing the need for larger field trials to evaluate the cost-efficacy of the approach in temperate regions. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Aedes , Wolbachia , Animais , Masculino , Feminino , Controle de Mosquitos/métodos , Fertilidade , Itália
6.
Animals (Basel) ; 12(18)2022 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-36139231

RESUMO

Heifers are a fundamental resource on farms, and their importance is reflected in both farm management and economy. Therefore, the selection of heifers to be reared on a farm should be carefully performed to select only the best animals. Genomic selection is available nowadays to evaluate animals in a fast and economic way. However, it is mainly used on the sire line and on performance traits. Ten farms were selected based on their 5-year records of average somatic cell count and evenly classified into high (>300,000 cells/mL) and low somatic cell count (<150,000 cells/mL). Genomic indexes (regarding both wellness and productive traits) were evaluated in 157 Italian Holstein heifers reared in the selected ten farms (90 from high-cells farms and 67 from low-cells ones). Linear mixed models were fitted to analyze the effects of the abovementioned genomic indexes on related phenotypes. Results have shown that farms classified into low somatic cell count had an overall better animal genomic pool compared to high somatic cell count ones. Additionally, the results shown in this study highlighted a difference in wellness genomic indexes in animals from farms with either a high or a low average somatic cell count. Applying genomic tools directly to heifer selection could improve economic aspects related to herd turnover.

7.
Sensors (Basel) ; 22(15)2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-35957285

RESUMO

In this paper, an FPGA (Field Programmable Gate Array)-based digital architecture for the measurement of quartz crystal microbalance (QCM) oscillating frequency of transient responses, i.e., in QCM-D (QCM and Dissipation) applications, is presented. The measurement system is conceived for operations in liquid, with short QCM transient responses due to the large mechanical load. The proposed solution allows for avoiding the complex processing systems typically required by the QCM-D techniques and grants frequency resolutions better than 1 ppm. The core of the architecture is a reciprocal digital frequency meter, combined with the preprocessing of the QCM signal through mixing operations, such as a step-down of the input frequency and reducing the measurement error. The measurement error is further reduced through averaging. Different strategies are proposed to implement the proposed measurement solution, comprising an all-digital circuit and mixed analog/digital ones. The performance of the proposed architectures is theoretically derived, compared, and analyzed by means of experimental data obtained considering 10 MHz QCMs and 200 µs long transient responses. A frequency resolution of about 240 ppb, which corresponds to a Sauerbrey mass resolution of 8 ng/cm2, is obtained for the all-digital solution, whereas for the mixed solution the resolution halves to 120 ppb, with a measurement time of about one second over 100 repetitions.


Assuntos
Técnicas Biossensoriais , Técnicas de Microbalança de Cristal de Quartzo , Técnicas Biossensoriais/métodos , Quartzo/química
8.
Vet Res ; 53(1): 60, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35906709

RESUMO

Small ruminant lentiviruses (SRLV) belong to the Retroviridae family and can cause various diseases. One of the most impacting diseases is visna-maedi, a complex disease characterized by long latencies and chronic progressive inflammatory events affecting the nervous system, lungs, mammary gland, and articular joints. A single nucleotide polymorphism (rs408593969, c.103G>A, missense mutation E35K) in the ovine transmembrane protein gene 154 (TMEM154) was identified as protective against small ruminant lentivirus infection in different herds worldwide. However, there is evidence in the scientific literature of a breed-specificity of this protective effect and, furthermore, there are still limited studies regarding the association between the animal genotype and the infecting virus genotype. Thus, the aim of this study was to further investigate the association between the animal genotype for the suggested protective mutation and the infecting virus genotype, in three different sheep breeds reared in northern Italy. The results obtained only partially confirmed the data available in the literature, as the protective effect was confirmed only for SRLV genotype A clusters, while other genotypes (namely B and E) infected AA and GA animals. Further studies with an experimental infection of specific virus genotypes in hosts with specific genotypes are required to confirm the larger number of cases the results obtained in this study.


Assuntos
Doenças das Cabras , Infecções por Lentivirus , Doenças dos Ovinos , Animais , Genótipo , Cabras , Lentivirus/genética , Infecções por Lentivirus/veterinária , Ruminantes , Ovinos , Doenças dos Ovinos/genética , Carneiro Doméstico
9.
Food Res Int ; 158: 111579, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35840264

RESUMO

In the present context of growing antimicrobial resistance (AMR) concern, understanding the distribution of AMR determinants in food matrices such as milk is crucial to protect consumers and maintain high food safety standards. Herein, the resistome of different dairy farms was investigated through a shotgun metagenomic sequencing approach, taking advantage of in-line milk filters as promising tools. The application of both the reads-based and the assembly-based approaches has allowed the identification of numerous AMR determinants, enabling a comprehensive resolution of the resistome. Notably most of the species harboring AMR genes were predicted to be Gram-negative genera, namely Enterobacter, Acinetobacter, Escherichia, and Pseudomonas, pointing out the role of these bacteria as reservoirs of AMR determinants. In this context, the use of de novo assembly has allowed a more holistic AMR detection strategy, while the reads-based approach has enabled the detection of AMR genes from low abundance bacteria, usually undetectable by assembly-based methods. The application of both reads-based and assembly-based approaches, despite being computationally demanding, has facilitated the comprehensive characterization of a food chain resistome, while also allowing the construction of complete metagenome assembled genomes and the investigation of mobile genetic elements. Our findings suggest that milk filters can successfully be used to investigate the resistome of bulk tank milk through the application of the shotgun metagenomic sequencing. In accordance with our results, raw milk can be considered a source of AMR bacteria and genes; this points out the importance of properly informing food business operators about the risk associated with poor hygiene practices in the dairy production environment and consumers of the potential microbial food safety risks derived from raw milk products consumption. Translating these findings as risk assessment outputs heralds the next generation of food safety controls.


Assuntos
Anti-Infecciosos , Enterobacteriaceae , Animais , Antibacterianos/farmacologia , Bactérias , Farmacorresistência Bacteriana/genética , Metagenoma , Leite/microbiologia , Moraxellaceae/genética
10.
Animals (Basel) ; 12(11)2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35681800

RESUMO

Food authentication in local breeds has important implications from both an economic and a qualitative point of view. Meat products from autochthonous breeds are of premium value, but can easily incur fraudulent or accidental substitution or mislabeling. The aim of this study was to identify a small number of SNPs using the Illumina PorcineSNP60 BeadChip for breed traceability, in particular of the Italian Nero Siciliano pig and its derived products. A panel of 12 SNPs was sufficient to discriminate Nero Siciliano pig from cosmopolitan breeds and wild boars. After adding 8 SNPs, the final panel of 20 SNPs allowed us to discriminate all the breeds involved in the study, to correctly assign each individual to its breed, and, moreover, to discriminate Nero Siciliano from first-generation hybrids. Almost all livestock breeds are being genotyped with medium- or high-density SNP panels, providing a large amount of information for many applications. Here, we proposed a method to select a reduced SNP panel to be used for the traceability of pig breeds.

11.
Parasit Vectors ; 15(1): 67, 2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35209944

RESUMO

BACKGROUND: Releasing considerable numbers of radiation-sterilized males is a promising strategy to suppress mosquito vectors. However, releases may also include small percentages of biting females, which translate to non-negligible numbers when releases are large. Currently, the effects of irradiation on host-seeking and host-biting behaviors have not been exhaustively investigated. Information is also lacking regarding the effects of sterilizing treatment on the endosymbiotic bacterium Wolbachia, which is known to affect the vector competence of infected mosquitos. METHODS: To ascertain the effects of irradiation on females, the pupae of two Aedes albopictus strains, differing in their natural or artificial Wolbachia infection type, and Aedes aegypti-which is not infected by Wolbachia-were treated with various doses of X-rays and monitored for key fitness parameters and biting behavior over a period of 2 weeks. The effect of radiation on Wolbachia was investigated by quantitative polymerase chain reaction (qPCR) and fluorescence in situ hybridization (FISH) analysis. RESULTS: Partial Aedes albopictus female sterility was achieved at 28 Gy, but the number of weekly bites more than doubled compared to that of the controls. Radiation doses of 35 and 45 Gy completely inhibited progeny production but did not significantly affect the survival or flight ability of Ae. albopictus females and caused a tripling of the number of bites per female per week (compared to untreated controls). These results were also confirmed in Ae. aegypti after treatment at 50 Gy. Wolbachia density decreased significantly in 45-Gy-irradiated females, with the greatest decreases in the early irradiation group (26 ± 2-h-old pupae). Wolbachia density also decreased as adults aged. This trend was confirmed in ovaries but not in extra-ovarian tissues. FISH analysis showed a strongly reduced Wolbachia-specific fluorescence in the ovaries of 13 ± 1-day-old females. CONCLUSIONS: These results suggest that, under sterile insect technique (SIT) programs, the vector capacity of a target population could increase with the frequency of the irradiated females co-released with the sterile males due to an increased biting rate. In the context of successful suppression, the related safety issues are expected to be generally negligible, but they should be conservatively evaluated when large-scale programs relying on imperfect sexing and high overflooding release ratios are run for long periods in areas endemic for arboviral diseases. Also, the effects of irradiation on the vector competence deserve further investigation.


Assuntos
Aedes , Infertilidade Masculina , Wolbachia , Aedes/microbiologia , Animais , Feminino , Hibridização in Situ Fluorescente , Masculino , Controle de Mosquitos/métodos , Wolbachia/genética
12.
Clin Case Rep ; 9(6): e04262, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34188928

RESUMO

Surgery in COVID-19 disease complicated by APF represents the last life-saving treatment option. The choice of the therapeutic period to indicate this approach is fundamental. In fact, the clinical stability of patient is necessary in order to allow single-lung ventilation and to minimize postoperative sequelae.

13.
Nature ; 590(7844): E1-E2, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33536643

Assuntos
Aedes , Wolbachia , Animais
14.
Animals (Basel) ; 11(2)2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33535694

RESUMO

Mastitis is an infectious disease affecting the mammary gland, leading to inflammatory reactions and to heavy economic losses due to milk production decrease. One possible way to tackle the antimicrobial resistance issue stemming from antimicrobial therapy is to select animals with a genetic resistance to this disease. Therefore, aim of this study was to analyze the genetic variability of the SNPs found in candidate genes related to mastitis resistance in Holstein Friesian bulls. Target regions were amplified, sequenced by Next-Generation Sequencing technology on the Illumina® MiSeq, and then analyzed to find correlation with mastitis related phenotypes in 95 Italian Holstein bulls chosen with the aid of a selective genotyping approach. On a total of 557 detected mutations, 61 showed different genotype distribution in the tails of the deregressed EBVs for SCS and 15 were identified as significantly associated with the phenotype using two different approaches. The significant SNPs were identified in intergenic or intronic regions of six genes, known to be key components in the immune system (namely CXCR1, DCK, NOD2, MBL2, MBL1 and M-SAA3.2). These SNPs could be considered as candidates for a future genetic selection for mastitis resistance, although further studies are required to assess their presence in other dairy cattle breeds and their possible negative correlation with other traits.

15.
Oncol Ther ; 8(2): 333-339, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32700042

RESUMO

Patients with epidermal growth factor receptor and anaplastic lymphoma kinase positive non-small cell lung cancer (NSCLC) generally respond poorly to treatment with immune checkpoint inhibitors such as anti-programmed cell death-1 (PD-1) or anti-programmed cell death ligand-1 (PD-L1) given with or without anti-cytotoxic T lymphocyte antigen-4 (CTLA-4) drugs. However, the efficacy of immunotherapy in patients with oncogene-addicted NSCLC harboring minor drivers, such as fusions in the rearranged during transfection (RET) gene, is still unclear. Here we describe two patients with RET-positive advanced NSCLC with PD-L1 expression ≥ 50% who developed progressive disease during first-line treatment with the anti-PD-1 agent pembrolizumab. In particular, while patient 2 was immediately switched to treatment with a selective RET inhibitor within the setting of a clinical trial, patient 1 responded to cytotoxic chemotherapy delivered at the time of progression while on pembrolizumab. These cases of NSCLC are discussed in the context of current literature, which seems to support our observation that patients with RET-positive NSCLC are unlikely to benefit from immunotherapy. Therefore, we suggest that for RET-positive patients with PD-L1 ≥ 50%, consideration should be given to upfront treatment approaches other than single-agent immunotherapy, namely selective RET inhibitors (if available) or regimens including cytotoxic chemotherapy.

16.
Oncol Ther ; 8(2): 341-350, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32700047

RESUMO

Oncogene-addicted non-small cell lung cancer (NSCLC) comprises a number of distinct disease subtypes, each of which is characterised by druggable genetic alterations. Among them, the receptor tyrosine kinase protein human epidermal receptor 2 (HER2) is occasionally found deregulated via gene mutation and/or amplification and/or protein overexpression. HER2 mutation, in particular, is a relatively rare condition which occurs in 1-4% of NSCLC patients, especially in those with adenocarcinoma histology and a never/light smoking history. However, the clinical relevance of a HER2 mutation in NSCLC relies on the fact that this genetic alteration has been associated with sensitivity to anti-HER2 therapies such as the monoclonal antibody trastuzumab or the pan-HER-tyrosine kinase inhibitor poziotinib. Here we describe the case of a NSCLC patient with an activating exon 20 G776VinsC mutation in the HER2 gene who responded well to multiple lines of trastuzumab-based therapies administered beyond progression and poziotinib given sequentially. In this specific case, the discovery of a druggable genetic alteration such as a mutation in the HER2 gene allowed for long-term control of the disease through the use of highly effective anti-HER2 therapies.

17.
Pest Manag Sci ; 76(4): 1324-1332, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31603613

RESUMO

BACKGROUND: Novel tools are needed to reduce the nuisance and risk of exotic arbovirus transmission associated with the colonization of temperate regions by Aedes albopictus. The incompatible insect technique (IIT) is a population suppression approach based on cytoplasmic incompatibility between males with manipulated endosymbionts and wild females. Here, we present the results of the first field experiment in Europe to assess the capacity of an Ae. albopictus line (ARwP) deprived of its natural endosymbiont Wolbachia and transinfected with a Wolbachia strain from the mosquito Culex pipiens, to sterilize wild females. RESULTS: We released ∼ 4500 ARwP males weekly for 6 weeks in a green area within urban Rome (Italy) and carried out egg (N = 13 442), female (N = 128) and male (N = 352) collections. Egg (N = 13 783) and female (N = 48) collections were also carried out at two untreated control sites. The percentage of viable eggs during release was, on average, significantly lower in treated sites than in control sites, with the greatest difference (16%) seen after the fourth release. The ARwP to wild male ratio in the release spots between day 3 after the first ARwP male release and day 7 after the last release was, on average, 7:10. Released males survived up to 2 weeks. Approximately 30% of females collected in the release spots showed 100% sterility and 20% showed strongly reduced fertility compared with control sites. CONCLUSIONS: Results support the potential of IIT as a tool contributing to Ae. albopictus control in the urban context, and stress the need for larger field trials to evaluate the cost-efficacy of the approach in suppressing wild populations. © 2019 Society of Chemical Industry.


Assuntos
Aedes , Wolbachia , Animais , Feminino , Fertilidade , Itália , Masculino , Controle de Mosquitos
19.
Parasit Vectors ; 11(Suppl 2): 649, 2018 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-30583743

RESUMO

BACKGROUND: The transinfection of the endosymbiotic bacterium Wolbachia provides a method to produce functionally sterile males to be used to suppress mosquito vectors. ARwP is a wPip Wolbachia infected Aedes albopictus which exhibits a bidirectional incompatibility pattern with wild-types. We coupled a modelistic approach with laboratory experiments to test ARwP as a control tool and evaluate the possible occurrence of population replacement following the release of ARwP females in a wild-type (SANG) population. Repeated male-only releases were simulated and tested in the laboratory in comparison with releases contaminated with 1% ARwP females. Model simulations also investigated how migration affects the outcome of contaminated releases. Finally, the mean level of egg fertility and the long-term evolution of populations constituted by two Wolbachia infection types were studied by testing SANG and ARwP Ae. albopictus and performing more general model simulations. RESULTS: The model was parametrized with laboratory data and simulations were compared with results of biological trials. Small populations of ARwP males and females were theoretically and experimentally demonstrated to rapidly become extinct when released in larger SANG populations. Male-only releases at a 5:1 ratio with respect to the wild-type males led to a complete suppression of the SANG population in a few generations. Contaminated releases were efficient as well but led to population replacement in the long term, when the wild-type population approached eradication. Migration significantly contrasted this trend as a 5% population turnover was sufficient to avoid any risk of population replacement. At equal frequencies between ARwP and SANG individuals, the mean egg fertility of the overall population was more than halved and suppression was self-sustaining until one of the two infection types extinguished. CONCLUSIONS: In the case of bidirectional incompatibility patterns, the repeated release of incompatible males with small percentages of contaminant females could lead to population replacement in confined environments while it could be managed to target high efficiency and sustainability in wild-type suppression when systems are open to migration. This possibility is discussed based on various contexts and taking into consideration the possibility of integration with other control methods such as SIT and the use of larvicides.


Assuntos
Aedes/microbiologia , Controle de Mosquitos/métodos , Mosquitos Vetores/microbiologia , Wolbachia/fisiologia , Animais , Citoplasma/microbiologia , Feminino , Fertilidade , Masculino , Controle da População , Medição de Risco
20.
PLoS Negl Trop Dis ; 12(7): e0006626, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30020933

RESUMO

Among the strategies targeting vector control, the exploitation of the endosymbiont Wolbachia to produce sterile males and/or invasive females with reduced vector competence seems to be promising. A new Aedes albopictus transinfection (ARwP-M) was generated by introducing wMel Wolbachia in the ARwP line which had been established previously by replacing wAlbA and wAlbB Wolbachia with the wPip strain. Various infection and fitness parameters were studied by comparing ARwP-M, ARwP and wild-type (SANG population) Ae. albopictus sharing the same genetic background. Moreover, the vector competence of ARwP-M related to chikungunya, dengue and zika viruses was evaluated in comparison with ARwP. ARwP-M showed a 100% rate of maternal inheritance of wMel and wPip Wolbachia. Survival, female fecundity and egg fertility did not show to differ between the three Ae. albopictus lines. Crosses between ARwP-M males and SANG females were fully unfertile regardless of male age while egg hatch in reverse crosses increased from 0 to about 17% with SANG males aging from 3 to 17 days. When competing with SANG males for SANG females, ARwP-M males induced a level of sterility significantly higher than that expected for an equal mating competitiveness (mean Fried index of 1.71 instead of 1). The overall Wolbachia density in ARwP-M females was about 15 fold higher than in ARwP, mostly due to the wMel infection. This feature corresponded to a strongly reduced vector competence for chikungunya and dengue viruses (in both cases, 5 and 0% rates of transmission at 14 and 21 days post infection) with respect to ARwP females. Results regarding Zika virus did not highlight significant differences between ARwP-M and ARwP. However, none of the tested ARwP-M females was capable at transmitting ZIKV. These findings are expected to promote the exploitation of Wolbachia to suppress the wild-type Ae. albopictus populations.


Assuntos
Aedes/microbiologia , Aedes/fisiologia , Controle de Mosquitos/métodos , Mosquitos Vetores/microbiologia , Mosquitos Vetores/fisiologia , Wolbachia/fisiologia , Aedes/genética , Animais , Cruzamento , Febre de Chikungunya/transmissão , Febre de Chikungunya/virologia , Vírus Chikungunya/fisiologia , Dengue/transmissão , Dengue/virologia , Vírus da Dengue/fisiologia , Feminino , Humanos , Infertilidade , Masculino , Mosquitos Vetores/genética , Zika virus/fisiologia , Infecção por Zika virus/transmissão , Infecção por Zika virus/virologia
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