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1.
PLoS One ; 19(3): e0290209, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38512822

RESUMO

Zika virus (ZIKV) outbreak caused one of the most significant medical emergencies in the Americas due to associated microcephaly in newborns. To evaluate the impact of ZIKV infection on neuronal cells over time, we retrieved gene expression data from several ZIKV-infected samples obtained at different time point post-infection (pi). Differential gene expression analysis was applied at each time point, with more differentially expressed genes (DEG) identified at 72h pi. There were 5 DEGs (PLA2G2F, TMEM71, PKD1L2, UBD, and TNFAIP3 genes) across all timepoints, which clearly distinguished between infected and healthy samples. The highest expression levels of all five genes were identified at 72h pi. Taken together, our results indicate that ZIKV infection greatly impacts human neural cells at early times of infection, with peak perturbation observed at 72h pi. Our analysis revealed that all five DEGs, in samples of ZIKV-infected human neural stem cells, remained highly upregulated across the timepoints evaluated. Moreover, despite the pronounced inflammatory host response observed throughout infection, the impact of ZIKV is variable over time. Finally, the five DEGs identified herein play prominent roles in infection, and could serve to guide future investigations into virus-host interaction, as well as constitute targets for therapeutic drug development.


Assuntos
Microcefalia , Infecção por Zika virus , Zika virus , Recém-Nascido , Humanos , Zika virus/genética , Infecção por Zika virus/epidemiologia , Neurônios/metabolismo , Expressão Gênica
2.
Doc Ophthalmol ; 148(1): 65-71, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38172268

RESUMO

PURPOSE: In this study, we report a case of a young adult with X-linked juvenile retinoschisis (XLRS) with a rare pathogenic variant in the RS1 gene (c.522 + 2 T > A). METHODS: Ophthalmological evaluation, optical coherence tomography, full-field and multifocal electroretinograms and extensive genetic screening of genes related to visual loss were carried out in the participant. RESULTS: Clinical ophthalmological exams revealed a mild to moderate impairment of visual acuity. Retinal imaging showed bilateral foveal schisis, as well as normal a-wave, reduction in the b-wave amplitudes in dark- and light- adapted full-field electroretinograms, and abnormal oscillatory potentials. We found also diffuse amplitude reduction in multifocal electroretinogram arrays. A canonical splice variant was identified in the RS1 gene (c.522 + 2 T > A). CONCLUSION: A rare pathogenic variant of the RS1 gene was associated with diffuse retinal involvement (central and peripheral retina), probably in inner retina, and mild to moderate visual acuity impairment. The phenotypical characterization of rare mutations is relevant to provide information about the disease.


Assuntos
Eletrorretinografia , Retinosquise , Adulto Jovem , Humanos , Retina/patologia , Retinosquise/diagnóstico , Retinosquise/genética , Mutação , Fóvea Central/patologia , Proteínas do Olho/genética , Tomografia de Coerência Óptica
3.
Med Vet Entomol ; 38(1): 83-98, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37867259

RESUMO

In this study, we analysed the molecular and morphometric differences of several populations of the putative sand fly vector Psychodopygus davisi (Root, 1934) (Diptera, Psychodidae, Phlebotominae) in Brazil. We amplified the 658 base pair fragments of the DNA barcoding region-cytochrome c oxidase subunit 1 (COI) gene-for 57 specimens of P. davisi and three specimens of Psychodopygus claustrei (Abonnenc, Léger & Fauran, 1979). We merged our data with public sequences of the same species available from GenBank. Then, the combined dataset-87 sequences and 20 localities-was analysed using population structure analysis and different species delimitation approaches. Geometric morphometry of wings was performed for 155 specimens of P. davisi populations from the North, Midwest and Southeast Brazilian regions, analysing the differences in centroid sizes and canonical variates. Molecular analysis indicated high intraspecific genetic distance values for P. davisi (maximum p distance = 5.52%). All algorithms identified P. davisi and P. claustrei as distinct molecular taxonomic units, despite the low interspecific distance (p distance to the nearest neighbour = 4.79%). P. davisi sequences were split into four genetic clusters by population structure analysis and at least five genetic lineages using intermediate scenarios of the species delimitation algorithms. The species validation analysis of BPP strongly supported the five-species model in our dataset. We found high genetic diversity in this taxon, which is in agreement with its wide geographic distribution in Brazil. Furthermore, the wing analysis showed that specimens from the Southeast Region of Brazil are different from those in the North and the Midwest. The evolutionary patterns of P. davisi populations in Brazil suggest the presence of candidate species, which need to be validated in future studies using a more comprehensive approach with both genomic data and morphological characters.


Assuntos
Phlebotomus , Psychodidae , Animais , Brasil , Psychodidae/genética , Evolução Biológica , Algoritmos , Código de Barras de DNA Taxonômico/veterinária , Filogenia
4.
Clin Oral Investig ; 27(7): 3469-3477, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36943514

RESUMO

OBJECTIVE: To compare the clinical outcomes of the tunnel technique (TUN) combined with either thin connective tissue graft (CTG) (TUN + thin CTG) (1 mm) or thick CTG (TUN + thick CTG) (2 mm) for the treatment of localized gingival recession (GR). MATERIAL AND METHODS: Twelve patients, with 24 maxillary localized type RT1 GR were randomly assigned into two groups. Clinical, esthetic, and patient-reported outcomes were evaluated at baseline and at 6-month follow-up. RESULTS: The TUN + thin CTG group showed a higher mean GR reduction (1.53 ± 0.66) (primary outcome variable) than the TUN + thick CTG group (1.44 ± 0.89), but no statistically significant difference was detected at the 6-month follow-up (p = 0.77). No statistically significant differences were found between TUN + thin CTG and TUN + thick CTG concerning complete root coverage (CRC) (58.3% versus 41.7%, respectively), gingival ticknness (GT) or Root-coverage Esthetic Score (RES) at 6 months. Regarding patient-reported outcomes, both groups reported having experienced similar pain at 7 days (p > 0.05). No statistically significant differences were found between the groups in the analysis of the aesthetic score. CONCLUSION: Both treatments showed a similar reduction in GR. In addition, similar CRC, GT, RES, pain and self-reported esthetics were achieved in both groups. CLINICAL RELEVANCE: Application of thin CTG provided a similar result than thick CTG for the treatment of RT1 localized GR.


Assuntos
Retração Gengival , Raiz Dentária , Humanos , Resultado do Tratamento , Raiz Dentária/cirurgia , Retalhos Cirúrgicos , Estética Dentária , Gengiva , Retração Gengival/cirurgia , Tecido Conjuntivo/transplante
5.
J Craniovertebr Junction Spine ; 14(4): 438-441, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38268691

RESUMO

Spinal epidural empyema (SEE) is a severe infectious disease of the spine which may cause significant morbidity and mortality. Surgical drainage of the empyema is a key feature. However, approach-related morbidity may be significant in very extensive collections. We present the case of a 55-year-old female with an empyema due to methicillin-susceptible Staphylococcus aureus spawning from C2 to S1. She underwent drainage of the pus through skip-level laminectomies and catheter epidural saline irrigation. The technique described was both safe and effective at treating the SEE, and the patient returned to normal life.

6.
Front Med (Lausanne) ; 10: 1275308, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38162881

RESUMO

Purpose: To compare the accuracy of machine learning (ML) algorithms to classify the sex of the participant from retinal thickness datasets in different retinal layers. Methods: This cross-sectional study involved 26 male and 38 female subjects. Data were acquired using HRA + OCT Spectralis, and the thickness and volume of 10 retinal layers were quantified. A total of 10 features were extracted from each retinal layer. The accuracy of various algorithms, including k-nearest-neighbor, support vector classifier, logistic regression, linear discriminant analysis, random forest, decision tree, and Gaussian Naïve Bayes, was quantified. A two-way ANOVA was conducted to assess the ML accuracy, considering both the classifier type and the retinal layer as factors. Results: A comparison of the accuracies achieved by various algorithms in classifying participant sex revealed superior results in datasets related to total retinal thickness and the retinal nerve fiber layer. In these instances, no significant differences in algorithm performance were observed (p > 0.05). Conversely, in other layers, a decrease in classification accuracy was noted as the layer moved outward in the retina. Here, the random forest (RF) algorithm demonstrated superior performance compared to the others (p < 0.05). Conclusion: The current research highlights the distinctive potential of various retinal layers in sex classification. Different layers and ML algorithms yield distinct accuracies. The RF algorithm's consistent superiority suggests its effectiveness in identifying sex-related features from a range of retinal layers.

7.
Acta Trop ; 235: 106619, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35905777

RESUMO

Culicoides biting midges are capable to transmit Oropouche virus, Bluetongue virus and Mansonella spp. This study aimed to assess the utility of DNA barcode as an alternative method in the Culicoides species identification. The study was conducted in Jamari National Forest. Biting midges were collected using HP light traps during four months, February, April, August and October 2018. Insects were morphologically identified to the species level, and rest of the body were subjected to DNA extraction and PCR targeting a fragment of the cytochrome c oxidase subunit I (COI) gene, which were analyzed and deposited in GenBank. A phylogenetic gene tree was reconstructed using RAxML software, and the sequences were assigned at Molecular Operational Taxonomic Unit (MOTU) level by species delimitation algorithms. According to morphological approach, 18 species of 2 subgenera and 7 species groups were identified. A total of 191 new COI barcodes from 18 species were generated. Of these, fifteen species have been deposited for the first time in all datasets in the world. These sequences allowed the correct identification of 188 and 187 specimens according to the BM and BCM criteria, respectively. The intraspecific genetic distances ranged from 0 to 16.5%, while the interspecific ones ranged from 2.1 to 27.1%. The nominal species Culicoides glabellus and C. tetrathyris splitted into three and two MOTUs, respectively, except for mPTP, indicating a cryptic diversity in these species. Also, sequences of C. pseudodiabolicus formed two MOTUs using all algorithms, except for PTP and ABGD, suggesting the existence of two potential species. In contrast, some barcodes of C. quasiparaensis and C. paraensis merged into a single MOTU, which can be explained by the complex characteristics of the paraensis group, since these species have similar morphological characters. Here, we provided the first COI barcodes for biting midges in Rondônia and Brazil, and demonstrates that these are sufficient to discriminate between some species.


Assuntos
Ceratopogonidae , Animais , Brasil , Ceratopogonidae/genética , DNA , Código de Barras de DNA Taxonômico , Filogenia
8.
Acta Trop ; 233: 106550, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35671783

RESUMO

One strategy to identify transmission foci is based on vector monitoring, and efficient methods are important for vector control. Our study evaluated different light sources (red, green, ultraviolet, blue, and incandescent light) to capture sand fly in Porto Velho, Brazil. We also evaluated Leishmania and blood meal sources in females. A total of 1,943 individuals were identified in 45 species level-taxa, with Trichophoromyia ubiquitalis (Mangabeira) (n = 364), Nyssomyia antunesi (n = 241), Bichromomyia flaviscutellata (Mangabeira) (n = 222), and Psychodopygus davisi (Root) (n = 148) being the most abundant. Incandescent light captured most individuals (n = 589), followed by blue (n = 471), green (n = 452), ultraviolet (n = 281) and red (n = 150). No significant difference was observed between the species composition and lights (PERMANOVA: Pseudo F = 1.29, p = 0.14, NMDS: Stress 0.18). The Shannon and Simpson indices demonstrated a high diversity captured using all lights. Our data demonstrated that LEDs are alternative devices for sand fly capture, with blue and green LEDs presenting similar results to incandescent light. 53 pools were analyzed, only one pool was positive for kDNA and hsp70 targets [Nyssomyia fraihai (Martins, Falão & Silva)] and identified as Endotrypanum spp., suggesting that other trypanosomatids may circulate in the locality. Choloepus hoffmanni (two-toed sloth) Peters, Homo sapiens Linnaeus, Proechimys gardneri (Gardner's spiny rat) Da Silva, and Tamandua tetradactyla (lesser anteater) (Linnaeus) were blood meal sources identified in females, increasing the knowledge about sources used by these insects.


Assuntos
Leishmania , Phlebotomus , Psychodidae , Animais , Brasil , DNA de Cinetoplasto , Feminino , Insetos Vetores , Leishmania/genética , Phlebotomus/genética , Psychodidae/genética
9.
Cytogenet Genome Res ; 162(5): 273-282, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36689934

RESUMO

Brazil is the largest producer of soybeans in the world. The vast extent of soybean plantations across the Brazilian territory exposes this crop to attack by several insects, including the velvetbean caterpillar, Anticarsia gemmatalis. One of the alternatives used to control this insect are the toxins produced by Bacillus thuringiensis (Bt). However, in some cases, resistance to these toxins has been reported in the laboratory. Despite the ecological and economic impact of the velvetbean caterpillar, there are few studies on the genetic structure of this species, especially with regard to microsatellites. In this paper, we carried out a comparative transcriptional analysis of microsatellites in resistant (RES) and susceptible (SUS) strains of A. gemmatalis challenged and not challenged with Bt toxins. According to the number of sequences analyzed in each group, a 7.9% simple sequence repeat (SSR) rate was identified for the SUS library, and 7.4% for SUSBt. For the RES group, this value was 8.5% and for the RESBt 7.7%. Most of the fragments found showed a shorter repeat pattern, located in mono- and trinucleotide motifs. Among the 128 types of SSR motifs, it was possible to notice a large amount of adenine and thymine in relation to guanine and cytosine, which was also seen in chromosomes after staining with base-specific fluorochromes DAPI/CMA3, highlighting DAPI-positive regions. Although the participation of microsatellites in the resistance mechanism of A. gemmatalis to Bt is not clear, the results obtained in this work contribute to a better understanding of the repetitive DNA found in transcribed regions of a non-model organism.


Assuntos
Bacillus thuringiensis , Mariposas , Animais , Toxinas de Bacillus thuringiensis , Bacillus thuringiensis/química , Bacillus thuringiensis/genética , Glycine max/genética , Brasil , Larva
10.
Biodivers Data J ; 10: e90015, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36761519

RESUMO

Background: Sandflies are insects important for the transmission cycles of the leishmaniases. Despite being studied since the 1960s in the State of Rondônia (Brazil), several gaps exist regarding our working knowledge of these insects. This study aimed to construct an up-to-date database of sandflies using complementary information from the speciesLink database and the scientific literature, as well as to elaborate integrated abundance maps. We identified 153,155 records of sandflies captured in Rondônia between 1965-2021; after exclusion, 147,258 reports (speciesLink - 3,408, Rondônia studies - 143,850) associated with 15 genera and 140 species were mapped. The most abundant species observed were Psychodopygusdavisi (Root, 1934) (43,818 records), Nyssomyiawhitmani (Antunes & Coutinho, 1939) (12,594), Psychodopyguscarrerai (Barretto, 1946) (11,840), Psychodopygushirsutus (Mangabeira, 1942) (9,676), Nyssomyiaantunesi (Coutinho, 1939) (8,847), Trichophoromyiaubiquitalis (Mangabeira, 1942) (5,505), Psychodopygusgeniculatus (Mangabeira, 1941) (4,644), Pintomyianevesi (Damasceno & Arouck, 1956) (4,140), Trichophoromyiaauraensis (Mangabeira, 1942) (3,579), Psychodopyguscomplexus (Mangabeira, 1941) (2,659), Nyssomyiafraihai (Martins, Falcão & Silva, 1979) (2,504) and Bichromomyiaflaviscutellata (Mangabeira, 1942) (1,418). A total of 20 records of Leishmania detection corresponded to eight sand fly species. The present dataset provides updated information on the distribution of sandflies of Rondônia, including those considered potential vectors of Leishmania, which should prove useful to guide future studies. New information: The present study provides an extensive dataset built from all studies reporting phlebotomine sandflies in the Brazilian State of Rondônia. Online distribution maps can aid scientists who wish to consult the updated list of sand fly species and view the distribution of these insects, as well as those considered potential vectors of Leishmania. The results of the present study can serve as the basis for future studies on sandflies conducted in the State.

11.
Rev Bras Parasitol Vet ; 30(4): e011021, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34852154

RESUMO

Leishmaniases are zoonotic diseases caused by protozoa of the genus Leishmania. The disease has two clinical manifestations described in humans: visceral (VL) and cutaneous (CL) leishmaniasis. In Brazil, there has been an expansion of human VL. The participation of the dog as a reservoir of Leishmania infantum, the agent of VL, is important for the epidemiology of the disease since canine cases generally precede human cases. The present study aimed to evaluate the occurrence of Leishmania spp. infection in dogs in the municipality of Ji-Paraná by PCR assays using blood samples. Leishmania DNA was detected in two of the 105 studied dogs. The PCR products were sequenced and confirmed that the two samples (1.90%) correspond to L. infantum. The dogs had allochthonous history. Therefore, the positive results found here should serve as a warning to public health agencies. This is because Ji-Paraná is the third municipality to register cases of canine leishmaniasis (CanL) in Rondônia state. Thus, reinforcing the importance of expanding studies on the epidemiology and surveillance of VL in the region.


Assuntos
Doenças do Cão , Leishmania infantum , Leishmaniose Visceral , Leishmaniose , Animais , Brasil/epidemiologia , Doenças do Cão/diagnóstico , Doenças do Cão/epidemiologia , Cães , Leishmaniose/veterinária , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/veterinária
12.
DST j. bras. doenças sex. transm ; 33: 1-5, dez.30, 2021.
Artigo em Inglês | LILACS | ID: biblio-1290991

RESUMO

Introduction: Syphilis is a problem for the Brazilian Public Health. Therefore, the Brazilian Ministry of Health has been promoting actions to fight this disease; among them, the "No Syphilis Project" stands out, and develops open educational resources (OER), among several activities. Objective: To analyze the open educational resources available in the SUS (the Brazilian Unified Health System) Virtual Learning Environment, focused on syphilis. Methods: This qualitative study, based on epistemology in the field of phenomenology, is a content analysis operated with the meanings constructed to parts of a set of texts and the objects of its analysis were the teaching plans of 19 educational resources available at AVASUS, which dealt with the theme "Syphilis". The analysis was organized into two unitss: The main purpose of the educational resource and Thematic focus of the educational resource. Results: The overlapping of clinical aspects of the disease to the detriment of socio-environmental aspects and the prevalence of informational objectives can be observed, with the exception of one resource that presented an objective that sought a more active action by the course participant. In the analysis unit 1 it was possible to identify the prevalence of objectives such as 'presenting' or 'conveying' content/information related to the disease. In the analysis unit 2 it was possible to identify the "classic" biomedical cycle of approaching a disease, focusing on diagnosis. Conclusion: The study contributed to the identification of gaps from the thematic and methodological point of view that can guide the planning for the construction of new educational resources.


Introdução: A sífilis é um problema de saúde pública do Brasil, que via seu Ministério da Saúde vem promovendo ações de enfrentamento da doença, entre as quais se destaca o "Projeto Sífilis Não", que desenvolve, entre diversas atividades, recursos educacionais abertos. Objetivo: Analisar os recursos educacionais abertos, disponíveis no ambiente virtual de aprendizagem do Sistema Único de Saúde (AVASUS), circunscritos na temática da sífilis. Métodos: Este estudo qualitativo, com base espistemológica no campo da fenomenologia, constitui-se em uma análise de conteúdo que operou com os significados contruídos com base em um conjunto de textos e teve como objetos de análise os planos de ensino de 19 recursos educacionais disponíveis no AVASUS e que versavam sobre o tema "sífilis". A análise foi organizada em duas unidades: objetivo principal do recurso educacional; e foco femático do recurso educacional. Resultados: Pode-se observar a sobreposição de aspectos clínicos da doença aos aspectos socioambientais e a prevalência de objetivos informacionais ­ com exceção de um recurso, cujo objetivo buscava uma ação mais ativa por parte do cursista. Na unidade de análise 1, foi possível identificar a prevalência de objetivos como "apresentar" ou "dar a conhecer" conteúdos/informação relacionados à doença. Na unidade de análise 2, foi possível verificar o ciclo biomédico "clássico" de abordagem de uma doença, com foco no diagnóstico. Conclusão: O estudo contribuiu para a identificação de lacunas dos pontos de vista temático e metodológico, que pode orientar o planejamento para a construção de novos recursos educacionais.


Assuntos
Humanos , Sífilis , Infecções Sexualmente Transmissíveis , Educação em Saúde , Comportamento Sexual , Sistema Único de Saúde , Comunicação
13.
Acta Trop ; 224: 106150, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34562421

RESUMO

Cutaneous Leishmaniasis (CL) is a disease caused by Leishmania species and transmitted by the bites of infected female sand fly species. The diversity of these insects in Rondônia State (where CL is the predominant form) is large but unexplored, and consequently the vector species are unknown. The purpose of this study was to evaluate the sand fly fauna in two environments (forest fragment and peridomicile) in rural areas of four municipalities of the state, DNA amplification of Leishmania species and the presence of blood meal sources for these insects. After identifying the species, sample coverage was applied to estimate the fauna coverage in each environment. Females were used to amplify and detect Leishmania DNA and blood meal sources, then posteriorly identified by sequencing. A total of 1706 individuals were included in 61 species, which was a sample coverage of 97% for the forest fragments (56 species), whereas 98% was observed (32 species) in peridomiciles. Next, 41 pools were prepared from 1227 females, and none were positive for Leishmania DNA. We observed 160 engorged females (forest fragments: 21, peridomiciles: 139) belonging to females of the Antunesi complex and another eight species. Two of these females were positive for Leishmania braziliensis-DNA: one in the Antunesi complex and one in Psychodopygus hirsutus. Seven blood meal sources were identified by sequencing analysis: Bos taurus and Sus scrofa from the peridomiciles, and Dasypus novemcinctus, Pecari tajacu, Philander canus, Plecturocebus bernhardi, and Tamandua tetradactyla from the forest fragments. Our data confirmed the feeding behavior of field-caught sand flies and could contribute to our understanding about local vectors and possible reservoirs in the transmission of Leishmania spp.


Assuntos
Leishmania , Leishmaniose Cutânea , Phlebotomus , Psychodidae , Animais , Bovinos , Feminino , Humanos , Insetos Vetores , Leishmania/genética
14.
Rev Soc Bras Med Trop ; 54: e02122021, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34431943

RESUMO

INTRODUCTION: This study evaluated the epidemiology of American cutaneous leishmaniasis in the immediate region of Ji-Paraná, Rondônia State. METHODS: Samples and epidemiological data were collected from 105 patients. RESULTS: Leishmania infection was observed in 58 (55.2%) patients, and Leishmania braziliensis was present in 82.9% of the 41 sequenced samples. Infected patients were predominantly male (93.1%). Leishmania infection was twice as prevalent among rural inhabitants versus urban inhabitants. Lesions were more frequent in the upper limbs (arms/hands, 41.82%). CONCLUSIONS: The present data corroborate the zoonotic profile of cutaneous leishmaniasis; this information could help to improve surveillance and control strategies.


Assuntos
Leishmania braziliensis , Leishmaniose Cutânea , Sequência de Bases , Brasil/epidemiologia , Humanos , Leishmania braziliensis/genética , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/epidemiologia , Masculino , População Rural
15.
Acta Trop ; 221: 106025, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34175266

RESUMO

Culicoides biting midges are insects involved in the transmission of filarial nematodes, protozoans, and viruses. Greater knowledge of Culicoides blood meal sources could improve our understanding of parasite transmission cycles. Our study used molecular tools to evaluate the blood meal sources of Culicoides biting midges from sylvatic environments. This study was conducted in Jamari National Forest, Rondônia, Brazil. Culicoides were captured using HP light traps positioned at ground level (1.5 m above ground) and in canopy (15 m above ground). To identify blood meal sources, females were subjected to DNA extraction and PCR targeting the cytb gene fragment, and the obtained sequences were analyzed and compared with sequences from GenBank. DNA extraction and PCR were performed on 455 Culicoides females, and blood meal sources were identified in 186 females. Thirty Culicoides specimens were collected from the Potosi trail and 156 were collected from the Santa Maria trail. A total of 22 species were captured; all 22 species were collected in canopy (100%) but only three species were collected at ground level (13.6%). The cytb fragment was amplified in 162 of 186 samples. Sample sequencing identified cytb DNA from nine blood-meal sources: Pauxi sp., Psophia viridis, Ramphastos tucanus tucanus, Choloepus didactylus, Choloepus hoffmanni, Tamandua tetradactyla, Ateles chamek, Homo sapiens and Pithecia irrorata. We observed that several different blood meal sources were utilized by a high diversity of Culicoides species. The abundance of Culicoides in the canopy may be related to the fact that the majority of blood meal hosts feed in treetops. We observed that C. (Hoffmania) sp. and C. coutinhoi tend to be more generalist, feeding on a range of mammals and piciform, gruiform and galliform birds. This data improves our knowledge of the feeding profile of biting midges from forest environments and should serve as a future basis for defining zoonotic transmission cycles.


Assuntos
Ceratopogonidae , Comportamento Alimentar , Animais , Brasil , Ceratopogonidae/genética , DNA , Feminino , Florestas , Humanos , Insetos Vetores , Mamíferos
16.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-434584

RESUMO

BackgroundMany SARS-CoV-2 variants of concern have emerged since the Covid-19 outburst, notably the lineages detected in the UK, South Africa, and Brazil. Their increased transmissibility and higher viral load put them in the spotlight. Much has been investigated on the ability of those new variants to evade antibody recognition. However, not enough attention has been given to pre-existing and induced SARS-CoV-2-specific CD8+ T cell responses during the natural course of infection by new lineages. MethodsIn this work, we investigated the SARS-CoV-2-specific CD8+ T cell epitopes from the main variants of concern and the potential of associated mutations to trigger or hinder CD8+ T-cells response. We also estimated the populations coverage of these different lineages, considering peptide binding predictions to class I HLA alleles from 29 countries to investigate differences in the fraction of individuals expected to respond to a given epitope set from new and previous lineages. ResultsWe observed a lower populational coverage for 20B/S.484K (P.2 lineage) in contrast to an increased coverage found for 20H/501Y.V2 (B.1.351 Lineage) and 20J/501Y.V3 (P.1 lineage) compared to a reference lineage. Moreover, mutations such as Spike N501Y and Nucleocapsid T205I were predicted to have an overall higher affinity through HLA-I than the reference sequence. ConclusionsIn summary, the data in this work provided evidence for the existence of potentially immunogenic and conserved epitopes across new SARS-CoV-2 variants, but also highlights the reduced populationals coverage for the Brazilian lineage P.2, suggesting its potential to evade from CD8+ T-cell responses. Our results also may guide efforts to characterize and validate relevant peptides to trigger CD8+ T-cell responses, and design new universal T-cell-inducing vaccine candidates that minimize detrimental effects of viral diversification and at the same time induce responses to a broad human population.

17.
J Med Entomol ; 58(3): 1115-1125, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33274392

RESUMO

The taxonomic identity of two species of sand flies, Psathyromyia pradobarrientosi (Le Pont, Matias, Martinez & Dujardin, 2004) and Psathyromyia runoides (Fairchild & Hertig, 1953) (Diptera, Psychodidae), was evaluated morphologically and molecularly based upon specimens collected in Brazilian states. The morphological component compared collected specimens with paratypes of Pa. runoides and Pa. pradobarrientosi and their descriptions. Phylogenetic analysis of coI sequences of Pa. pradobarrientosi showed a well-supported group distinct from Pa. runoides. Morphologically, Psathyromyia runoides and Pa. pradobarrientosi males are distinguished by characteristics of the aedeagal ducts and parameral sheath in the genitalia; females are distinguished by the number and shape of the teeth in the cibarium and by the shape of the spermathecae. Given the morphological similarity between the males and the absence of the description of the female of Pa. pradobarrientosi, it is possible that specimens previously identified as Pa. runoides in Brazil are in fact Pa. pradobarrientosi.


Assuntos
Psychodidae/anatomia & histologia , Psychodidae/genética , Animais , Proteínas de Insetos/análise , Filogenia , Psychodidae/classificação
18.
J Med Entomol ; 58(1): 465-470, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-32652043

RESUMO

Culicoides biting midges are small hematophagous flies, some species of which transmit pathogens to livestock and humans. In the Brazilian Amazon Basin, Culicoides diversity has remained largely unexamined. Jamari National Forest (JNF) is a conservation area in Rondônia State where research and environmental education are conducted in conjunction with the protection of natural resources, and the recovery of degraded areas. The present study augments our knowledge of Culicoides diversity in JNF. The survey collected 640 individuals from 41 species; 632 individuals were collected by HP light trap and 8 were collected by the BG Sentinel trap. Twelve species are first-time records for Rondônia: Culicoides acotylus Lutz, Culicoides albuquerquei Wirth & Blanton, Culicoides baniwa Felippe-Bauer, Culicoides bricenoi Ortiz, Culicoides brownei Spinelli, Culicoides carsiomelas Wirth & Blanton, Culicoides debilipalpis Lutz, Culicoides forattinii Ortiz, Culicoides ginesi Ortiz, Culicoides profundus Santarém, Felippe-Bauer & Trindade, Culicoides pseudoreticulatus Santarém, Felippe-Bauer & Castellón, and Culicoides spurius Santarém, Felippe-Bauer & Trindade. The most abundant species were Culicoides glabrior Macfie, Culicoides pseudodiabolicus Fox, Culicoides debilipalpis, Culicoides quasiparaensis Clastrier, and Culicoides brownei Spinelli. The present study updates the Culicoides species count in Rondônia to 55, and highlights the importance of JNF as a hotbed for biting midge diversity.


Assuntos
Distribuição Animal , Ceratopogonidae/fisiologia , Florestas , Animais , Brasil , Feminino , Masculino
19.
Acta Trop ; 213: 105757, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33189711

RESUMO

Cutaneous Leishmaniasis (CL) is a vector-borne disease caused by Leishmania species and transmitted by infected female sand flies. CL is widely distributed in Brazil, but knowledge about vectors and transmission cycles could be complex according to localities. The sand fly fauna in Rondônia State is extensive, diverse, and largely unexplored. Although the state records a mean of 1,000 CL cases per year, the vectors of CL are unknown. The aim of this study was to assess phlebotomine sand fly fauna composition using diversity indexes (Shannon [H'] and Simpson [1/D]) and to detect the prevalence of Leishmania infection to verify potential vectors in three ecotopes: (i) forest fragment (FF), (ii) forest edge (FE), and (iii) peridomicile (PE). Captures were performed in four rural districts in the municipality of Porto Velho. A total of 7,026 specimens were captured comprising 72 species, and individuals classified in subgenus level. Overall, the most abundant species were Lutzomyia davisi (n: 1,105), Lutzomyia melloi (n: 760), Lutzomyia auraensis (n: 738) and Lutzomyia antunesi (n: 479). Fauna was most diverse in the FF ecotope (H' = 20.2, 1/D = 11.2), followed by the FE (H' = 18.0, 1/D = 10.1) and PE (H' = 16.6, 1/D = 10.1) ecotopes. Leishmania DNA was detected in 24 of 232 pools. In every ecotope, Leishmania naiffi DNA was identified in the following sand fly species: Lu. antunesi, Lu. davisi, Lu. hirsuta hirsuta, Lu. shawi, Lu. sordellii and Lu. (Trichophoromyia) spp. This observation may indicate that a Le. naiffi transmission focus is present in the study localities. In addition, Leishmania lainsoni was detected in Lutzomyia (Trichophoromyia) spp. Our findings show that sand fly fauna in the study localities is diverse, that Leishmania parasites are circulating in all three ecotopes, and that some sand fly species may be implicated in the transmission of Leishmania to humans in localities evaluated.


Assuntos
Insetos Vetores/parasitologia , Leishmania/isolamento & purificação , Leishmaniose Cutânea/transmissão , Doenças Negligenciadas/parasitologia , Psychodidae/parasitologia , Animais , Brasil/epidemiologia , Feminino , Florestas , Humanos , Leishmania/genética , Leishmaniose Cutânea/epidemiologia , Doenças Negligenciadas/epidemiologia
20.
Rev. bras. parasitol. vet ; 30(4): e011021, 2021. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1351874

RESUMO

Abstract Leishmaniases are zoonotic diseases caused by protozoa of the genus Leishmania. The disease has two clinical manifestations described in humans: visceral (VL) and cutaneous (CL) leishmaniasis. In Brazil, there has been an expansion of human VL. The participation of the dog as a reservoir of Leishmania infantum, the agent of VL, is important for the epidemiology of the disease since canine cases generally precede human cases. The present study aimed to evaluate the occurrence of Leishmania spp. infection in dogs in the municipality of Ji-Paraná by PCR assays using blood samples. Leishmania DNA was detected in two of the 105 studied dogs. The PCR products were sequenced and confirmed that the two samples (1.90%) correspond to L. infantum. The dogs had allochthonous history. Therefore, the positive results found here should serve as a warning to public health agencies. This is because Ji-Paraná is the third municipality to register cases of canine leishmaniasis (CanL) in Rondônia state. Thus, reinforcing the importance of expanding studies on the epidemiology and surveillance of VL in the region.


Resumo As leishmanioses são doenças causadas por protozoários do gênero Leishmania. A doença apresenta duas manifestações clínicas: leishmaniose visceral (LV) e cutânea (LC). No Brasil, a LV está em expansão. A participação do cão como reservatório é importante para a epidemiologia da doença, pois os casos caninos geralmente precedem os humanos. O presente estudo avaliou a ocorrência de LV em cães (LVC) do município de Ji-Paraná por meio de ensaios de PCR, utilizando-se amostras de sangue. O DNA de Leishmania foi detectado em dois dos 105 cães estudados. Os produtos da PCR foram sequenciados e confirmaram que duas amostras (1,90%) eram Leishmania infantum. Os cães tinham histórico alóctone. Os resultados positivos encontrados servem de alerta aos órgãos públicos de saúde. Isso porque Ji-Paraná é o terceiro município a registrar casos de LVC no estado de Rondônia. Dessa forma, reforça-se a importância da ampliação dos estudos sobre a epidemiologia e vigilância da LV na região.


Assuntos
Animais , Cães , Leishmaniose/veterinária , Leishmania infantum , Doenças do Cão/diagnóstico , Doenças do Cão/epidemiologia , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Brasil/epidemiologia , Leishmaniose Visceral/veterinária
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