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1.
Proteomics ; : e2100313, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38850190

RESUMEN

Evolutionary relationships among parasites of the subfamily Leishmaniinae, which comprises pathogen agents of leishmaniasis, were inferred based on differential protein expression profiles from mass spectrometry-based quantitative data using the PhyloQuant method. Evolutionary distances following identification and quantification of protein and peptide abundances using Proteome Discoverer and MaxQuant software were estimated for 11 species from six Leishmaniinae genera. Results clustered all dixenous species of the genus Leishmania, subgenera L. (Leishmania), L. (Viannia), and L. (Mundinia), sister to the dixenous species of genera Endotrypanum and Porcisia. Placed basal to the assemblage formed by all these parasites were the species of genera Zelonia, Crithidia, and Leptomonas, so far described as monoxenous of insects although eventually reported from humans. Inferences based on protein expression profiles were congruent with currently established phylogeny using DNA sequences. Our results reinforce PhyloQuant as a valuable approach to infer evolutionary relationships within Leishmaniinae, which is comprised of very tightly related trypanosomatids that are just beginning to be phylogenetically unraveled. In addition to evolutionary history, mapping of species-specific protein expression is paramount to understand differences in infection processes, tissue tropisms, potential to jump from insects to vertebrates including humans, and targets for species-specific diagnostic and drug development.

2.
Neuroimage ; 297: 120718, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38964563

RESUMEN

N, N-dimethyltryptamine (DMT) is a psychedelic tryptamine acting on 5-HT2A serotonin receptors, which is associated with intense visual hallucinatory phenomena and perceptual changes such as distortions in visual space. The neural underpinnings of these effects remain unknown. We hypothesised that changes in population receptive field (pRF) properties in the primary visual cortex (V1) might underlie visual perceptual experience. We tested this hypothesis using magnetic resonance imaging (MRI) in a within-subject design. We used a technique called pRF mapping, which measures neural population visual response properties and retinotopic maps in early visual areas. We show that in the presence of visual effects, as documented by the Hallucinogen Rating Scale (HRS), the mean pRF sizes in V1 significantly increase in the peripheral visual field for active condition (inhaled DMT) compared to the control. Eye and head movement differences were absent across conditions. This evidence for short-term effects of DMT in pRF may explain perceptual distortions induced by psychedelics such as field blurring, tunnel vision (peripheral vision becoming blurred while central vision remains sharp) and the enlargement of nearby visual space, particularly at the visual locations surrounding the fovea. Our findings are also consistent with a mechanistic framework whereby gain control of ongoing and evoked activity in the visual cortex is controlled by activation of 5-HT2A receptors.


Asunto(s)
Alucinógenos , Imagen por Resonancia Magnética , Humanos , Alucinógenos/farmacología , Adulto , Masculino , Femenino , Adulto Joven , Corteza Visual/efectos de los fármacos , Corteza Visual/fisiología , Corteza Visual/diagnóstico por imagen , Distorsión de la Percepción/efectos de los fármacos , Distorsión de la Percepción/fisiología , N,N-Dimetiltriptamina/farmacología , Campos Visuales/efectos de los fármacos , Campos Visuales/fisiología , Percepción Visual/efectos de los fármacos , Percepción Visual/fisiología , Triptaminas/farmacología , Corteza Visual Primaria/efectos de los fármacos , Corteza Visual Primaria/fisiología , Corteza Visual Primaria/diagnóstico por imagen , Mapeo Encefálico/métodos
3.
Parasitol Res ; 122(12): 3169-3180, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37848747

RESUMEN

Xenarthra mammals can be found from southern North America to southern South America, including all Brazilian biomes. Although it has been shown that Xenarthra mammals can play a role as reservoirs for several zoonotic agents, few studies investigate the diversity of piroplasmids (Apicomplexa: Piroplasmida) in this group of mammals. Taking into account that piroplasmids can cause disease in animals and humans, understanding the prevalence and diversity of piroplasmids in Xenarthra mammals would contribute to conservation efforts for this group of animals as well as to infer risk areas for transmission of emergent zoonosis. The present study aimed to investigate the occurrence and molecular identity of piroplasmids in free-living mammals of the Superorder Xenarthra from four Brazilian states (Mato Grosso do Sul, São Paulo, Rondônia, and Pará). For this, DNA was extracted from blood or spleen samples from 455 animals. A nested PCR based on the 18S rRNA gene was used as screening for piroplasmids. Of the 455 samples analyzed, 25 (5.5%) were positive. Additionally, PCR assays based on 18S rRNA near-complete, cox-1, cox-3, hsp70, cytB, ß-tubulin genes and the ITS-1 intergenic region were performed. Five out of 25 positive samples also tested positive for ITS-1-based PCR. The phylogenetic analysis positioned three 18S rRNA sequences detected in Priodontes maximus into the same clade of Babesia sp. detected in marsupials (Didelphis albiventris, Didelphis marsupialis, and Monodelphis domestica) and Amblyomma dubitatum collected from opossums and coatis in Brazil. On the other hand, the 18S rRNA sequence obtained from Dasypus novemcinctus was closely related to a Theileria sp. sequence previously detected in armadillos from Mato Grosso State, grouping in a subclade within the Theileria sensu stricto clade. In the phylogenetic analysis based on the ITS-1 region, the sequences obtained from Myrmecophaga tridactyla and Tamandua tetradactyla were placed into a single clade, apart from the other piroplasmid clades. The present study demonstrated the molecular occurrence of Piroplasmida in anteaters and Babesia sp. and Theileria sp. in armadillos from Brazil.


Asunto(s)
Babesia , Didelphis , Marsupiales , Piroplasmida , Theileria , Xenarthra , Animales , Humanos , Brasil/epidemiología , Armadillos , Filogenia , ARN Ribosómico 18S/genética , Theileria/genética , Babesia/genética , Piroplasmida/genética
4.
Mem Inst Oswaldo Cruz ; 117: e220125, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36383785

RESUMEN

BACKGROUND: Trypanosoma cruzi shows an exuberant genetic diversity. Currently, seven phylogenetic lineages, called discrete typing units (DTUs), are recognised: TcI-TcVI and Tcbat. Despite advances in studies on T. cruzi and its populations, there is no consensus regarding its heterogeneity. OBJECTIVES: This study aimed to perform molecular characterisation of T. cruzi strains, isolated in the state of São Paulo, to identify the DTUs involved and evaluate their genetic diversity. METHODS: T. cruzi strains were isolated from biological samples of chronic chagasic patients, marsupials and triatomines through culture techniques and subjected to molecular characterisation using the fluorescent fragment length barcoding (FFLB) technique. Subsequently, the results were correlated with complementary information to enable better discrimination between the identified DTUs. FINDINGS: It was possible to identify TcI in two humans and two triatomines; TcII/VI in 19 humans, two marsupials and one triatomine; and TcIII in one human host, an individual that also presented a result for TcI, which indicated the possibility of a mixed infection. Regarding the strains characterised by the TcII/VI profile, the correlation with complementary information allowed to suggest that, in general, these parasite populations indeed correspond to the TcII genotype. MAIN CONCLUSIONS: The TcII/VI profile, associated with domestic cycles and patients with chronic Chagas disease, was the most prevalent among the identified DTUs. Furthermore, the correlation of the study results with complementary information made it possible to suggest that TcII is the predominant lineage of this work.


Asunto(s)
Enfermedad de Chagas , Marsupiales , Trypanosoma cruzi , Humanos , Animales , Trypanosoma cruzi/genética , Filogenia , Brasil , Enfermedad de Chagas/parasitología , Genotipo , Variación Genética/genética
5.
Conscious Cogn ; 84: 102987, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32777734

RESUMEN

INTRODUCTION: Color constancy, a property of conscious color experience, maintains object color appearance across illuminant changes. We investigated the neural correlates of subliminal vs. conscious stimulus deviations of color constancy manipulations. METHODS: Behavioral and Oddball EEG/ERP experiments were conducted (n = 20). Psychophysical illuminant variation discrimination thresholds were first estimated, to establish individual perceptual awareness ranges, allowing for simulation of natural daylight spectral and spatial variations on colored surfaces, at different ambiguity levels. RESULTS: Behavioral results validated illuminant choice. ERPs showed a significant modulation of posterior P1 component specifically for the subliminal global uniform deviation condition, respecting color constancy. Neural correlates of conscious percepts were identified at posterior N2-P3 latencies, parietal (P3b) and frontal regions. CONCLUSIONS: We identified an early subliminal correlate of low-level illuminant change, which reflects automatic unconscious detection of global color constancy deviations. Its suppression under conscious perception is probably due to top-down suppression according to prediction error models.


Asunto(s)
Concienciación/fisiología , Corteza Cerebral/fisiología , Percepción de Color/fisiología , Estado de Conciencia/fisiología , Potenciales Evocados/fisiología , Estimulación Subliminal , Adolescente , Adulto , Electroencefalografía , Femenino , Humanos , Masculino , Adulto Joven
6.
Genomics ; 111(3): 407-417, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-29499243

RESUMEN

Trypanosoma vivax is a parasite widespread across Africa and South America. Immunological methods using recombinant antigens have been developed aiming at specific and sensitive detection of infections caused by T. vivax. Here, we sequenced for the first time the transcriptome of a virulent T. vivax strain (Lins), isolated from an outbreak of severe disease in South America (Brazil) and performed a computational integrated analysis of genome, transcriptome and in silico predictions to identify and characterize putative linear B-cell epitopes from African and South American T. vivax. A total of 2278, 3936 and 4062 linear B-cell epitopes were respectively characterized for the transcriptomes of T. vivax LIEM-176 (Venezuela), T. vivax IL1392 (Nigeria) and T. vivax Lins (Brazil) and 4684 for the genome of T. vivax Y486 (Nigeria). The results presented are a valuable theoretical source that may pave the way for highly sensitive and specific diagnostic tools.


Asunto(s)
Epítopos de Linfocito B/genética , Transcriptoma , Trypanosoma/genética , Animales , Epítopos de Linfocito B/inmunología , Cabras , Trypanosoma/inmunología
8.
BMC Genomics ; 19(1): 770, 2018 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-30355302

RESUMEN

BACKGROUND: Trypanosoma conorhini and Trypanosoma rangeli, like Trypanosoma cruzi, are kinetoplastid protist parasites of mammals displaying divergent hosts, geographic ranges and lifestyles. Largely nonpathogenic T. rangeli and T. conorhini represent clades that are phylogenetically closely related to the T. cruzi and T. cruzi-like taxa and provide insights into the evolution of pathogenicity in those parasites. T. rangeli, like T. cruzi is endemic in many Latin American countries, whereas T. conorhini is tropicopolitan. T. rangeli and T. conorhini are exclusively extracellular, while T. cruzi has an intracellular stage in the mammalian host. RESULTS: Here we provide the first comprehensive sequence analysis of T. rangeli AM80 and T. conorhini 025E, and provide a comparison of their genomes to those of T. cruzi G and T. cruzi CL, respectively members of T. cruzi lineages TcI and TcVI. We report de novo assembled genome sequences of the low-virulent T. cruzi G, T. rangeli AM80, and T. conorhini 025E ranging from ~ 21-25 Mbp, with ~ 10,000 to 13,000 genes, and for the highly virulent and hybrid T. cruzi CL we present a ~ 65 Mbp in-house assembled haplotyped genome with ~ 12,500 genes per haplotype. Single copy orthologs of the two T. cruzi strains exhibited ~ 97% amino acid identity, and ~ 78% identity to proteins of T. rangeli or T. conorhini. Proteins of the latter two organisms exhibited ~ 84% identity. T. cruzi CL exhibited the highest heterozygosity. T. rangeli and T. conorhini displayed greater metabolic capabilities for utilization of complex carbohydrates, and contained fewer retrotransposons and multigene family copies, i.e. trans-sialidases, mucins, DGF-1, and MASP, compared to T. cruzi. CONCLUSIONS: Our analyses of the T. rangeli and T. conorhini genomes closely reflected their phylogenetic proximity to the T. cruzi clade, and were largely consistent with their divergent life cycles. Our results provide a greater context for understanding the life cycles, host range expansion, immunity evasion, and pathogenesis of these trypanosomatids.


Asunto(s)
Genoma de Protozoos , Genómica , Trypanosoma cruzi/genética , Trypanosoma rangeli/genética , Trypanosoma/genética , Biología Computacional/métodos , Metabolismo Energético/genética , Genómica/métodos , Genotipo , Tipificación Molecular , Familia de Multigenes , Filogenia , Seudogenes , Trypanosoma/clasificación , Trypanosoma/metabolismo , Trypanosoma/patogenicidad , Trypanosoma cruzi/clasificación , Trypanosoma cruzi/metabolismo , Trypanosoma cruzi/patogenicidad , Trypanosoma rangeli/clasificación , Trypanosoma rangeli/metabolismo , Trypanosoma rangeli/patogenicidad , Virulencia/genética
9.
J Mol Evol ; 84(2-3): 104-115, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28210761

RESUMEN

We screened the genomes of a broad panel of kinetoplastid protists for genes encoding proteins associated with the RNA interference (RNAi) system using probes from the Argonaute (AGO1), Dicer1 (DCL1), and Dicer2 (DCL2) genes of Leishmania brasiliensis and Crithidia fasciculata. We identified homologs for all the three of these genes in the genomes of a subset of these organisms. However, several of these organisms lacked evidence for any of these genes, while others lacked only DCL2. The open reading frames encoding these putative proteins were structurally analyzed in silico. The alignments indicated that the genes are homologous with a high degree of confidence, and three-dimensional structural models strongly supported a functional relationship to previously characterized AGO1, DCL1, and DCL2 proteins. Phylogenetic analysis of these putative proteins showed that these genes, when present, evolved in parallel with other nuclear genes, arguing that the RNAi system genes share a common progenitor, likely across all Kinetoplastea. In addition, the genome segments bearing these genes are highly conserved and syntenic, even among those taxa in which they are absent. However, taxa in which these genes are apparently absent represent several widely divergent branches of kinetoplastids, arguing that these genes were independently lost at least six times in the evolutionary history of these organisms. The mechanisms responsible for the apparent coordinate loss of these RNAi system genes independently in several lineages of kinetoplastids, while being maintained in other related lineages, are currently unknown.


Asunto(s)
Crithidia fasciculata/genética , ADN de Cinetoplasto/genética , Leishmania braziliensis/genética , Trypanosomatina/genética , Secuencia de Aminoácidos/genética , Proteínas Argonautas/genética , Evolución Biológica , ADN de Cinetoplasto/metabolismo , Eucariontes/genética , Evolución Molecular , Genoma/genética , Filogenia , Interferencia de ARN/fisiología , Ribonucleasa III/genética , Alineación de Secuencia/métodos , Sintenía/genética
10.
Parasitol Res ; 116(7): 1907-1916, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28512673

RESUMEN

Previous studies showed infections of Hepatozoon caimani in wild populations of caimans in wide regions from Brazil; some of those demonstrated that trophic chain are linked to natural infections through paratenic hosts or by the direct ingestion of vectors. These studies life cycle of H. caimani contributed inestimably to the knowledge of transmission routes, yet but lack enhancement tools for better detail of parasite. This study reports the forms in the blood and tissues, and also partial molecular characterization of the H. caimani following part of the 18S rRNA region. In the southern Pantanal, there were sampling 39 adult caimans (Caiman yacare), where 31 (79.5%) were parasitized by H. caimani. Free gametocytes had an average intensity of 19.6% and intraerythrocytic forms 7.42%, in the blood smears. In stained smears of the liver and lungs of naturally infected caimans which were examined, monozoic and dizoic cysts were found in these tissues, generally next to the vessels. In the histopathology, meronts were observed in the wall of vessels from liver and kidney ducts. Blood samples were forwarded to PCR process and produced amplicons with about 600 and 900 bp, respectively, for the primers HEPF300/HEP900 and HEMO1/HEMO2. This was the first report of molecular confirmation of Hepatozoon in populations of naturally infected caimans of morphological detail of the gametocytes in scanning electron microscopy and histology of merogony in livers and kidneys of C. yacare.


Asunto(s)
Caimanes y Cocodrilos/parasitología , Coccidiosis/veterinaria , Eucoccidiida/crecimiento & desarrollo , Estadios del Ciclo de Vida , Animales , Brasil/epidemiología , Coccidiosis/epidemiología , Coccidiosis/parasitología , ADN Protozoario/sangre , ADN Protozoario/química , Eucoccidiida/clasificación , Eucoccidiida/genética , Eucoccidiida/ultraestructura , Filogenia , Análisis de Secuencia de ADN/veterinaria
11.
J Eukaryot Microbiol ; 63(5): 610-22, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26932133

RESUMEN

We described the phylogenetic affiliation, development in cultures and ultrastructural features of a trypanosome of Leptodacylus chaquensis from the Pantanal biome of Brazil. In the inferred phylogeny, this trypanosome nested into the Anura clade of the basal Aquatic clade of Trypanosoma, but was separate from all known species within this clade. This finding enabled us to describe it as Trypanosoma herthameyeri n. sp., which also infects other Leptodacylus species from the Pantanal and Caatinga biomes. Trypanosoma herthameyeri multiplies as small rounded forms clumped together and evolving into multiple-fission forms and rosettes of epimastigotes released as long forms with long flagella; scarce trypomastigotes and glove-like forms are common in stationary-phase cultures. For the first time, a trypanosome from an amphibian was observed by field emission scanning electron microscopy, revealing a cytostome opening, well-developed flagellar lamella, and many grooves in pumpkin-like forms. Transmission electron microscopy showed highly developed Golgi complexes, relaxed catenation of KDNA, and a rich set of spongiome tubules in a regular parallel arrangement to the flagellar pocket as confirmed by electron tomography. Considering the basal position in the phylogenetic tree, developmental and ultrastructural data of T. herthameyeri are valuable for evolutionary studies of trypanosome architecture and cell biology.


Asunto(s)
Anuros/parasitología , Filogenia , Trypanosoma/clasificación , Trypanosoma/ultraestructura , Tripanosomiasis/veterinaria , Animales , Anuros/sangre , Biodiversidad , Brasil , Clasificación , ADN Protozoario/genética , Ecología , Ecosistema , Tomografía con Microscopio Electrónico/métodos , Flagelos/ultraestructura , Aparato de Golgi/ultraestructura , Especificidad del Huésped , Microscopía Electrónica de Rastreo/métodos , Microscopía Electrónica de Transmisión/métodos , Trypanosoma/crecimiento & desarrollo , Trypanosoma/aislamiento & purificación , Tripanosomiasis/sangre , Tripanosomiasis/diagnóstico , Tripanosomiasis/parasitología
12.
Biomater Adv ; 162: 213931, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38924805

RESUMEN

Microbial colonization and development of infections in wounds is a sign of chronicity. The prevailing approach to manage and treat these wounds involves dressings. However, these often fail in effectively addressing infections, as they struggle to both absorb exudates and maintain optimal local moisture. The system here presented was conceptualized with a three-layer design: the outer layer made of a fibrous polycaprolactone (PCL) film, to act as a barrier for preventing microorganisms and impurities from reaching the wound; the intermediate layer formed of a sodium alginate (SA) hydrogel loaded with ampicillin (Amp) for fighting infections; and the inner layer comprised of a fibrous film of PCL and polyethylene glycol (PEG) for facilitating cell recognition and preventing wound adhesion. Thermal evaluations, degradation, wettability and release behavior testing confirmed the system resistance overtime. The sandwich demonstrated the capability for absorbing exudates (≈70 %) and exhibited a controlled release of Amp for up to 24 h. Antimicrobial testing was performed against Staphylococcus aureus and Escherichia coli, as representatives of Gram-positive and Gram-negative bacteria: >99 % elimination of bacteria. Cell cytotoxicity assessments showed high cytocompatibility levels, confirming the safety of the proposed sandwich system. Adhesion assays confirmed the system ease of detaching without mechanical effort (0.37 N). Data established the efficiency of the sandwich-like system, suggesting promising applications in infected wound care.


Asunto(s)
Alginatos , Antibacterianos , Escherichia coli , Poliésteres , Staphylococcus aureus , Infección de Heridas , Alginatos/química , Infección de Heridas/tratamiento farmacológico , Infección de Heridas/microbiología , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antibacterianos/química , Antibacterianos/administración & dosificación , Poliésteres/química , Ampicilina/farmacología , Ampicilina/uso terapéutico , Ampicilina/química , Humanos , Hidrogeles/química , Polietilenglicoles/química , Animales , Vendajes , Pruebas de Sensibilidad Microbiana , Ratones , Cicatrización de Heridas/efectos de los fármacos
13.
Acta Trop ; : 107385, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39251171

RESUMEN

We assessed the diversity of triatomines, the rates of natural infection, and the discrete typing units (DTUs) of Trypanosoma cruzi isolated from them in two municipalities in the state of Sergipe, Brazil. Active searches for triatomines were conducted in the peridomicily and wild enviroments of 10 villages within the two municipalities. Triatomines were taxonomically identified and their feces were extracted using the abdominal compression method. Parasite detection was performed using optical microscopy. For Trypanosoma cruzi genotyping via PCR-FFLB, 151 samples of the subspecies Triatoma brasiliensis macromelasoma and Triatoma brasiliensis brasiliensis were isolated from both municipalities. In total, 505 triatomines were collected, with Triatoma brasiliensis macromelasoma being the most frequent species (58.81%). Triatoma b. brasiliensis was the only species in both peridomestic and wild environments. Regarding the other species, T. pseudomaculata was found only in the peridomestic environment; and T. b. macromelasoma and Psammolestes tertius were found in the wild environment. Three Discrete Typing Units were identified: TcI (87.51%) detected in T. b. brasiliensis and T. b. macromelasoma, TcI+TcIII (10.41%) in T. b. macromelasoma, and TcI+Trypanosoma rangeli (2.08%) in T. b. macromelasoma. It is concluded that T. b. macromelasoma is the species collected most frequently in the studied region and the one that presents the highest rates of natural infection, highlighting its epidemiological importance for the vectorial transmission of Chagas disease in Sergipe.

14.
BMC Evol Biol ; 13: 190, 2013 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-24015778

RESUMEN

BACKGROUND: Trypanosomatids of the genera Angomonas and Strigomonas live in a mutualistic association characterized by extensive metabolic cooperation with obligate endosymbiotic Betaproteobacteria. However, the role played by the symbiont has been more guessed by indirect means than evidenced. Symbiont-harboring trypanosomatids, in contrast to their counterparts lacking symbionts, exhibit lower nutritional requirements and are autotrophic for essential amino acids. To evidence the symbiont's contributions to this autotrophy, entire genomes of symbionts and trypanosomatids with and without symbionts were sequenced here. RESULTS: Analyses of the essential amino acid pathways revealed that most biosynthetic routes are in the symbiont genome. By contrast, the host trypanosomatid genome contains fewer genes, about half of which originated from different bacterial groups, perhaps only one of which (ornithine cyclodeaminase, EC:4.3.1.12) derived from the symbiont. Nutritional, enzymatic, and genomic data were jointly analyzed to construct an integrated view of essential amino acid metabolism in symbiont-harboring trypanosomatids. This comprehensive analysis showed perfect concordance among all these data, and revealed that the symbiont contains genes for enzymes that complete essential biosynthetic routes for the host amino acid production, thus explaining the low requirement for these elements in symbiont-harboring trypanosomatids. Phylogenetic analyses show that the cooperation between symbionts and their hosts is complemented by multiple horizontal gene transfers, from bacterial lineages to trypanosomatids, that occurred several times in the course of their evolution. Transfers occur preferentially in parts of the pathways that are missing from other eukaryotes. CONCLUSION: We have herein uncovered the genetic and evolutionary bases of essential amino acid biosynthesis in several trypanosomatids with and without endosymbionts, explaining and complementing decades of experimental results. We uncovered the remarkable plasticity in essential amino acid biosynthesis pathway evolution in these protozoans, demonstrating heavy influence of horizontal gene transfer events, from Bacteria to trypanosomatid nuclei, in the evolution of these pathways.


Asunto(s)
Aminoácidos Esenciales/biosíntesis , Betaproteobacteria/genética , Transferencia de Gen Horizontal , Simbiosis , Trypanosomatina/genética , Trypanosomatina/microbiología , Betaproteobacteria/fisiología , Evolución Biológica , Genoma Bacteriano , Filogenia , Trypanosomatina/clasificación , Trypanosomatina/metabolismo
15.
Vet Res ; 44: 1, 2013 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-23289625

RESUMEN

The present study was aimed at investigating the effect of experimental infection by Trypanosoma vivax in different stages of pregnancy, determining the pathogenesis of reproductive failure, and confirming transplacental transmission. We used 12 pregnant ewes distributed into four experimental groups: G1, was formed by three ewes infected with T. vivax in the first third of pregnancy (30 days); G2 comprised three infected ewes in the final third of pregnancy (100 days); G3 and G4 were composed of three non-infected ewes with the same gestational period, respectively. Each ewe of G1 and G2 was inoculated with 1.25×10(5) tripomastigotes. Clinical examination, determination of parasitemia, serum biochemistry (albumin, total protein, glucose, cholesterol, and urea), packed cell volume (PCV), serum progesterone, and pathological examination were performed. Placenta, amniotic fluid, blood and tissues from the fetuses and stillbirths were submitted to PCR. Two ewes of G1 (Ewe 1 and 3) presented severe infection and died in the 34th and 35th days post-infection (dpi), respectively; but both fetuses were recovered during necropsy. In G2, Ewe 5 aborted two fetuses on the 130th day (30 dpi) of pregnancy; and Ewe 6 aborted one fetus in the 140th day (40 dpi) of gestation. Ewes 2 and 4 delivered two weak lambs that died five days after birth. Factors possibly involved with the reproductive failure included high parasitemia, fever, low PCV, body score, serum glucose, total protein, cholesterol, and progesterone. Hepatitis, pericarditis, and encephalitis were observed in the aborted fetuses. The presence of T. vivax DNA in the placenta, amniotic fluid, blood, and tissues from the fetuses confirms the transplacental transmission of the parasite. Histological lesion in the fetuses and placenta also suggest the involvement of the parasite in the etiopathogenesis of reproductive failure in ewes.


Asunto(s)
Aborto Veterinario/parasitología , Transmisión Vertical de Enfermedad Infecciosa/veterinaria , Enfermedades de las Ovejas/transmisión , Trypanosoma vivax/fisiología , Tripanosomiasis/veterinaria , Animales , Brasil , Femenino , Parasitemia/parasitología , Parasitemia/transmisión , Parasitemia/veterinaria , Reacción en Cadena de la Polimerasa/veterinaria , Embarazo , Distribución Aleatoria , Ovinos , Enfermedades de las Ovejas/parasitología , Tripanosomiasis/parasitología , Tripanosomiasis/transmisión
16.
Cancers (Basel) ; 15(6)2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-36980693

RESUMEN

(1) Background: While obesity is a known independent risk factor in the development of melanoma, there is no consensus on its influence on melanoma prognosis. (2) Methods: In a monocentric retrospective study, data was collected from patients who underwent sentinel lymph node (SLN) biopsy for stage IB-IIC melanoma between 2013 and 2018. Patients were divided into groups according to their body mass index (BMI). The association between BMI and melanoma features, as well as the risk factors for metastases in SLN were examined. (3) Results: Of the 1001 patients, 336 had normal weight (BMI < 25), 402 were overweight (BMI >= 25 and <30), 173 obese (BMI >= 30 and <35) and 90 extremely obese (BMI >= 35). Overweightness and obesity were associated with higher tumor thicknesses at time of diagnosis. Ulceration was not influenced by the patient's weight. Metastases in sentinel lymph node was almost twice more likely in extremely obese patients than in normal weight patients. Independent risk factors for metastases in SLN in our study were tumor thickness, ulceration, and BMI > 35. (4) Conclusions: This is the first study to show higher metastases rates in high-BMI patients with melanoma, raising important questions regarding the screening and treatment of this specific patient population.

17.
Front Neurosci ; 17: 1295608, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38164245

RESUMEN

Introduction: Emotion recognition is a core feature of social perception. In particular, perception of dynamic facial emotional expressions is a major feature of the third visual pathway. However, the classical N170 visual evoked signal does not provide a pure correlate of such processing. Indeed, independent component analysis has demonstrated that the N170 component is already active at the time of the P100, and is therefore distorted by early components. Here we implemented, a dynamic face emotional paradigm to isolate a more pure face expression selective N170. We searched for a neural correlate of perception of dynamic facial emotional expressions, by starting with a face baseline from which a facial expression evolved. This allowed for a specific facial expression contrast signal which we aimed to relate with social communication abilities and cortical gamma-aminobutyric acid (GABA) levels. Methods: We recorded event-related potentials (ERPs) and Magnetic Resonance (MRS) measures in 35 typically developing (TD) children, (10-16 years) sex-matched, during emotion recognition of an avatar morphing/unmorphing from neutral to happy/sad expressions. This task allowed for the elimination of the contribution low-level visual components, in particular the P100, by morphing baseline isoluminant neutral faces into specific expressions, isolating dynamic emotion recognition. Therefore, it was possible to isolate a dynamic face sensitive N170 devoid of interactions with earlier components. Results: We found delayed N170 and P300, with a hysteresis type of dependence on stimulus trajectory (morphing/unmorphing), with hemispheric lateralization. The delayed N170 is generated by an extrastriate source, which can be related to the third visual pathway specialized in biological motion processing. GABA levels in visual cortex were related with N170 amplitude and latency and predictive of worse social communication performance (SCQ scores). N170 latencies reflected delayed processing speed of emotional expressions and related to worse social communication scores. Discussion: In sum, we found a specific N170 electrophysiological signature of dynamic face processing related to social communication abilities and cortical GABA levels. These findings have potential clinical significance supporting the hypothesis of a spectrum of social communication abilities and the identification of a specific face-expression sensitive N170 which can potentially be used in the development of diagnostic and intervention tools.

18.
Acta Trop ; 244: 106945, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37207993

RESUMEN

Bats (Mammalia, Chiroptera) represent the second largest group of mammals. Due to their ability to fly and adapt and colonize different niches, bats act as reservoirs of several potentially zoonotic pathogens. In this context, the present work aimed to investigate, using molecular techniques, the occurrence of blood-borne agents (Anaplasmataceae, Coxiella burnetii, hemoplasmas, hemosporidians and piroplasmids) in 198 vampire bats sampled in different regions of Brazil and belonging to the species Desmodus rotundus (n = 159), Diphylla ecaudata (n = 31) and Diaemus youngii (n = 8). All vampire bats liver samples were negative in PCR assays for Ehrlichia spp., Anaplasma spp., piroplasmids, hemosporidians and Coxiella burnetii. However, Neorickettsia sp. was detected in liver samples of 1.51% (3/198) through nested PCR based on the 16S rRNA gene in D. rotundus and D. ecaudata. This is the first study to report Neorickettsia sp. in vampire bats. Hemoplasmas were detected in 6.06% (12/198) of the liver samples using a PCR based on the 16S rRNA gene. The two 16S rRNA sequences obtained from hemoplasmas were closely related to sequences previously identified in vampire and non-hematophagous bats from Belize, Peru and Brazil. The genotypic analysis identified a high diversity of bat-associated hemoplasma genotypes from different regions of the world, emphasizing the need for studies on this subject, in order to better understand the mechanisms of co-evolution between this group of bacteria and their vertebrate hosts. The role of neotropical bat-associated Neorickettsia sp. and bats from Brazil in the biological cycle of such agent warrant further investigation.


Asunto(s)
Quirópteros , Neorickettsia , Animales , Neorickettsia/genética , Brasil/epidemiología , ARN Ribosómico 16S/genética , Reacción en Cadena de la Polimerasa , Filogenia
19.
Pathogens ; 12(12)2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38133293

RESUMEN

The Leishmaniinae subfamily of the Trypanosomatidae contains both genus Zelonia (monoxenous) and Endotrypanum (dixenous). They are amongst the nearest known relatives of Leishmania, which comprises many human pathogens widespread in the developing world. These closely related lineages are models for the genomic biology of monoxenous and dixenous parasites. Herein, we used comparative genomics to identify the orthologous groups (OGs) shared among 26 Leishmaniinae species to investigate gene family expansion/contraction and applied two phylogenomic approaches to confirm relationships within the subfamily. The Endotrypanum monterogeii and Zelonia costaricensis genomes were assembled, with sizes of 29.9 Mb and 38.0 Mb and 9.711 and 12.201 predicted protein-coding genes, respectively. The genome of E. monterogeii displayed a higher number of multicopy cell surface protein families, including glycoprotein 63 and glycoprotein 46, compared to Leishmania spp. The genome of Z. costaricensis presents expansions of BT1 and amino acid transporters and proteins containing leucine-rich repeat domains, as well as a loss of ABC-type transporters. In total, 415 and 85 lineage-specific OGs were identified in Z. costaricensis and E. monterogeii. The evolutionary relationships within the subfamily were confirmed using the supermatrix (3384 protein-coding genes) and supertree methods. Overall, this study showed new expansions of multigene families in monoxenous and dixenous parasites of the subfamily Leishmaniinae.

20.
Heliyon ; 9(12): e22747, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38125462

RESUMEN

Triatomines are hematophagous insects of epidemiological importance as they are vectors of Chagas disease. The first report of Rhodnius stali Lent, Jurberg & Galvão, 1993 in Rondônia, Brazil, is described. The insects were captured on palm trees of the genus Oenocarpus sp. Two adult male specimens of R. stali were identified and were found to be infected with Trypanosoma cruzi and Trypanosoma rangeli. The confirmation of this Rhodnius species in Rondônia increases the number of triatomines from nine to ten species in this state.

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