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1.
Cytotherapy ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38639672

RESUMO

BACKGROUND AIMS: The marketing authorization of Advanced Therapy Medicinal Products (ATMPs) in Brazil is recent. The features of these therapies impose specialized regulatory action and are consequently challenging for developers. The goal of this study was to identify the industry's experience in clinical development, marketing authorization and access to ATMPs through the Unified Health System (SUS, acronym in Portuguese), from a regulatory perspective. METHODS: A survey containing structured questions was conducted among research participants who work at companies that commercialize ATMPs. A descriptive analysis was performed. RESULTS: We invited 15 foreign pharmaceutical companies, of which 10 agreed to participate. Overall, participants assessed that Brazil has a well-established regulatory system, especially the sanitary registration by the National Health Surveillance Agency (Anvisa), which ensures the quality, safety, and efficacy of the products. The Agency's good interaction with the regulated sector, the harmonization of sanitary and ethical assessment systems with other countries, and the analysis time in the biosafety assessment of Genetically Modified Organisms (GMOs) stand out as positive in industry's evaluation. On the other hand, it is important to advance the pricing regulation for these products since Brazilian regulations do not establish specific criteria for ATMP. One of the biggest challenges is the difficulty for the SUS in reimbursing these very high-cost therapies, especially using current Health Technology Assessment (HTA) methods. CONCLUSIONS: Considering the increasing number of approvals of cell and gene therapies in Brazil in the coming years, a close dialogue between the industry and the public sector is recommended to advance regulatory improvements (pricing and HTA). Additionally, the construction of policies to promote the national Health Economic-Industrial Complex, based on a mission-oriented vision that encourages innovative models of financing, especially those that consider risk-sharing and co-financing technologies, will help provide the population with universal, equitable and sustainable access to ATMP in the SUS.

2.
Int J Parasitol ; 54(6): 257-266, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38452964

RESUMO

Trichomonas vaginalis is a medically important protozoan parasite, and a deep-branching, evolutionarily divergent unicellular eukaryote that has conserved several key features of eukaryotic gene expression. Trichomonas vaginalis possesses a metazoan/plant-like capping apparatus, mRNAs with a cap 1 structure and spliceosomes containing the five small nuclear RNAs (snRNAs). However, in contrast to metazoan and plant snRNAs, the structurally conserved T. vaginalis snRNAs were initially identified as lacking the canonical guanosine cap nucleotide. To explain this unusual condition, we sought to investigate transcriptional and processing features of the spliceosomal snRNAs in this protist. Here, we show that T. vaginalis spliceosomal snRNA genes mostly lack typical eukaryotic promoters. In contrast to other eukaryotes, the putative TATA box in the T. vaginalis U6 snRNA gene was found to be dispensable for transcription or RNA polymerase selectivity. Moreover, U6 transcription in T. vaginalis was virtually insensitive to tagetitoxin compared with other cellular transcripts produced by the same RNA polymerase III. Most important and unexpected, snRNA transcription in T. vaginalis appears to bypass capping as we show that these transcripts retain their original 5'-triphosphate groups. In conclusion, transcription and processing of spliceosomal snRNAs in T. vaginalis deviate considerably from the conventional rules of other eukaryotes.


Assuntos
RNA Nuclear Pequeno , Spliceossomos , Transcrição Gênica , Trichomonas vaginalis , RNA Nuclear Pequeno/genética , RNA Nuclear Pequeno/metabolismo , Trichomonas vaginalis/genética , Trichomonas vaginalis/metabolismo , Spliceossomos/metabolismo , Spliceossomos/genética , Processamento Pós-Transcricional do RNA , RNA de Protozoário/metabolismo , RNA de Protozoário/genética , Animais
3.
Biotechnol J ; 19(1): e2300219, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37876300

RESUMO

Chitinases are widely studied enzymes that have already found widespread application. Their continued development and valorisation will be driven by the identification of new and improved variants and/or novel applications bringing benefits to industry and society. We previously identified a novel application for chitinases wherein the Candida albicans cell wall surface chitinase 3 (Cht3) was shown to have potential in vaccine applications as a subunit antigen against fungal infections. In the present study, this enzyme was investigated further, developing production and purification protocols, enriching our understanding of its properties, and advancing its application potential. Cht3 was heterologously expressed in Pichia pastoris and a 4-step purification protocol developed and optimised: this involves activated carbon treatment, hydrophobic interaction chromatography, ammonium sulphate precipitation, and gel filtration chromatography. The recombinant enzyme was shown to be mainly O-glycosylated and to retain the epitopes of the native protein. Functional studies showed it to be highly specific, displaying activity on chitin, chitosan, and chito-oligosaccharides larger than chitotriose only. Furthermore, it was shown to be a stable enzyme, exhibiting activity, and stability over broad pH and temperature ranges. This study represents an important step forward in our understanding of Cht3 and contributes to its development for application.


Assuntos
Quitinases , Quitosana , Candida albicans/genética , Candida albicans/metabolismo , Quitinases/genética , Quitinases/química , Proteínas , Quitina/química , Quitina/metabolismo , Concentração de Íons de Hidrogênio
4.
ACS Appl Nano Mater ; 6(18): 17149-17160, 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37772266

RESUMO

The deposition of zinc-zinc oxide nanoparticles (Zn-ZnO NPs) onto porous Ta2O5 surfaces enriched with calcium phosphate by DC magnetron sputtering was investigated to improve the surface antimicrobial activity without triggering an inflammatory response. Different sizes and amounts of Zn NPs obtained by two optimized different depositions and an additional thin carbon (C) layer deposited over the NPs were explored. The deposition of the Zn NPs and the C layer mitigates the surface porosity, increasing the surface hydrophobicity and decreasing the surface roughness. The possible antimicrobial effect and immune system activation of Zn-ZnO NPs were investigated in Candida albicans and macrophage cells, respectively. It was found that the developed surfaces displayed a fungistatic behavior, as they impair the growth of C. albicans between 5 and 24 h of culture. This behavior was more evident on the surfaces with bigger NPs and the highest amounts of Zn. The same trend was observed in both reactive oxygen species (ROS) generation and loss of C. albicans' membrane integrity. After 24 h of culture, cell toxicity was also dependent on the amount of the NPs. Cell toxicity was observed in surfaces with the highest amount of Zn NPs and with the C layer, while cells were able to grow without any signs of cytotoxicity in the porous surfaces with the lowest amount of NPs. The same Zn-dose-dependent behavior was noticed in the TNF-α production. The Zn-containing surfaces show a vastly inferior cytokine secretion than the lipopolysaccharide (LPS)-stimulated cells, indicating that the modified surfaces do not induce an inflammatory response from macrophage cells. This study provides insights for understanding the Zn amount threshold that allows a simultaneous inhibition of the fungi growth with no toxic effect and the main antimicrobial mechanisms of Zn-ZnO NPs, contributing to future clinical applications.

5.
Biomed Pharmacother ; 166: 115362, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37633051

RESUMO

Opportunistic fungi cause lethal systemic infections and impose high medical costs to health systems. The World Health Organization has recognized the importance of fungal infections, including them in its global priority list guiding research, development, and discovery of new therapeutic approaches. Fungal vaccine development has been proposed as one of the treatment and prevention strategies in the last decade. In this study, we present the design of a lipid antigen delivery system based on Dioctadecyldimethylammonium bromide: Monoolein (DODAB: MO) containing recombinant Candida albicans Chitinase 3 (Cht3) for modulation the immune response against fungal infections. Several DODAB:MO liposomes containing Cht3 were prepared and those prepared by the incubation method and containing 5 µg/mL Cht3 were selected due to their favorable size, ζ-potential and stability, suited for antigen delivery applications. The encapsulation of Cht3 in these liposomes resulted in a significant increase in cellular uptake compared to empty liposomes, demonstrating their efficacy in delivering the antigen. Moreover, the liposomes proved to be safe for use in immunization procedures. Subcutaneous administration of Cht3 liposomes elicited a Th1/Th17 immune response profile, associated with the production of high levels of antibodies against Cht3. These antibodies recognized both the native and the recombinant forms of the protein, opsonizing mother-yeast at the cell scars, which has the potential to disrupt cell separation and hinder yeast growth. The findings suggest that the designed lipid antigen delivery system shows promise as a potential candidate for enhancing immune responses against fungal infections, offering a valuable strategy for future fungal vaccine development.


Assuntos
Quitinases , Vacinas Fúngicas , Micoses , Vacinas , Candida albicans , Lipossomos , Anticorpos , Lipídeos
6.
PLoS Pathog ; 19(8): e1011563, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37585473

RESUMO

Trichomonas vaginalis is a human protozoan parasite that causes trichomoniasis, a prevalent sexually transmitted infection. Trichomoniasis is accompanied by a shift to a dysbiotic vaginal microbiome that is depleted of lactobacilli. Studies on co-cultures have shown that vaginal bacteria in eubiosis (e.g. Lactobacillus gasseri) have antagonistic effects on T. vaginalis pathogenesis, suggesting that the parasite might benefit from shaping the microbiome to dysbiosis (e.g. Gardnerella vaginalis among other anaerobes). We have recently shown that T. vaginalis has acquired NlpC/P60 genes from bacteria, expanding them to a repertoire of nine TvNlpC genes in two distinct clans, and that TvNlpCs of clan A are active against bacterial peptidoglycan. Here, we expand this characterization to TvNlpCs of clan B. In this study, we show that the clan organisation of NlpC/P60 genes is a feature of other species of Trichomonas, and that Histomonas meleagridis has sequences related to one clan. We characterized the 3D structure of TvNlpC_B3 alone and with the inhibitor E64 bound, probing the active site of these enzymes for the first time. Lastly, we demonstrated that TvNlpC_B3 and TvNlpC_B5 have complementary activities with the previously described TvNlpCs of clan A and that exogenous expression of these enzymes empower this mucosal parasite to take over populations of vaginal lactobacilli in mixed cultures. TvNlpC_B3 helps control populations of L. gasseri, but not of G. vaginalis, which action is partially inhibited by E64. This study is one of the first to show how enzymes produced by a mucosal protozoan parasite may contribute to a shift on the status of a microbiome, helping explain the link between trichomoniasis and vaginal dysbiosis. Further understanding of this process might have significant implications for treatments in the future.


Assuntos
Tricomoníase , Vaginite por Trichomonas , Trichomonas vaginalis , Feminino , Humanos , Trichomonas vaginalis/genética , Lactobacillus/genética , Peptidoglicano , N-Acetil-Muramil-L-Alanina Amidase , Disbiose , Bactérias
7.
Mol Microbiol ; 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37485746

RESUMO

Trichomonas vaginalis is an extracellular protozoan parasite of the human urogenital tract, responsible for a prevalent sexually transmitted infection. Trichomoniasis is accompanied by a dysbiotic microbiome that is characterised by the depletion of host-protective commensals such as Lactobacillus gasseri, and the flourishing of a bacterial consortium that is comparable to the one seen for bacterial vaginosis, including the founder species Gardnerella vaginalis. These two vaginal bacteria are known to have opposite effects on T. vaginalis pathogenicity. Studies on extracellular vesicles (EVs) have been focused on the direction of a microbial producer (commensal or pathogen) to a host recipient, and largely in the context of the gut microbiome. Here, taking advantage of the simplicity of the human cervicovaginal microbiome, we determined the molecular cargo of EVs produced by L. gasseri and G. vaginalis and examined how these vesicles modulate the interaction of T. vaginalis and host cells. We show that these EVs carry a specific cargo of proteins, which functions can be attributed to the opposite roles that these bacteria play in the vaginal biome. Furthermore, these bacterial EVs are delivered to host and protozoan cells, modulating host-pathogen interactions in a way that mimics the opposite effects that these bacteria have on T. vaginalis pathogenicity. This is the first study to describe side-by-side the protein composition of EVs produced by two bacteria belonging to the opposite spectrum of a microbiome and to demonstrate that these vesicles modulate the pathogenicity of a protozoan parasite. Such as in trichomoniasis, infections and dysbiosis co-occur frequently resulting in significant co-morbidities. Therefore, studies like this provide the knowledge for the development of antimicrobial therapies that aim to clear the infection while restoring a healthy microbiome.

8.
Sports Biomech ; : 1-14, 2023 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-37332236

RESUMO

This case study examined the association between 50 m freestyle and speed curve parameters of a world-class Paralympic swimmer and analysed the changes in speed curves and their frequency components across her performance levels. From 2018 to 2021, a visually impaired female swimmer (26.59 s in 50 m freestyle, S12 class) underwent 22 tests to obtain instantaneous speed synchronised with video recording. She regularly performed 50 m freestyle in competitions and time trials. The fast Fourier transformation method converted the speed signal into frequency domains and determined the relative contribution of the harmonics with two maxima and minima (H2, arms actions) and six maxima and minima (H6, legs actions). The functional paired t-test compared the speed curves at the beginning (PRE) and end (POST) of the analysed period. The 50 m freestyle time correlated with average speed (r = -0.50, p = 0.02). The contribution of H6 increased in the first year and remained large, whereas the contribution of H2 was lower throughout the whole period. POST was faster than PRE in five moments that coincide with the downward leg kick moments. These changes allowed her to stay longer at the upper part of the curve and improve performance over time.

9.
Sports Biomech ; 22(12): 1734-1751, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34402417

RESUMO

Swimming analysts aid coaches and athletes in the decision-making by providing evidence-based recommendations. The aim of this narrative review was to report the best practices of swimming analysts that have been supporting high-performance athletes. It also aims to share how swimming analysts can translate applied research into practice. The role of the swimming analyst, as part of a holistic team supporting high-performance athletes, has been expanding and is needed to be distinguished from the job scope of a swimming researcher. As testing can be time-consuming, analysts must decide what to test and when to conduct the evaluation sessions. Swimming analysts engage in the modelling and forecast of the performance, that in short- and mid-term can help set races target-times, and in the long-term provide insights on talent and career development. Races can be analysed by manual, semi-automatic or fully automatic video analysis with single or multi-cameras set-ups. The qualitative and quantitative analyses of the swim strokes, start, turns, and finish are also part of the analyst job scope and associated with race performance goals. Land-based training is another task that can be assigned to analysts and aims to enhance the performance, prevent musculoskeletal injuries and monitor its risk factors.


Assuntos
Desempenho Atlético , Natação , Humanos , Fenômenos Biomecânicos , Atletas
10.
mBio ; 13(4): e0132322, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-35968950

RESUMO

The protozoan parasite Trichomonas vaginalis causes trichomoniasis, a prevalent human urogenital infection with significant morbidity that is commonly associated with vaginal dysbiosis. Exacerbation of T. vaginalis pathogenicity has been related to endosymbionts, including mycoplasma, and thought for a while to be solely attributable to Mycoplasma hominis. In a recent publication, Margarita and colleagues (https://journals.asm.org/doi/10.1128/mbio.00918-22) showed that endosymbiosis extends to a second species of mycoplasma known as "Candidatus Mycoplasma girerdii." Those authors confirmed the strong association of T. vaginalis with both species of mycoplasma by reassessing clinical samples. Additionally, they showed that in vitro symbiosis of protozoa and bacteria resulted in the modulation of gene expression of T. vaginalis and enhancement of parasite cytoadhesion and hemolytic activity in culture assays. In this commentary, we portray T. vaginalis as a synergistically interacting multimicrobe organism-a "microbial piñata"-whose endosymbionts contribute significantly to the pathophysiology of this medically important protozoan parasite.


Assuntos
Mycoplasma , Trichomonas vaginalis , Bactérias/genética , Feminino , Humanos , Mycoplasma hominis/genética , Trichomonas vaginalis/genética , Vagina/microbiologia
12.
Nanomaterials (Basel) ; 12(9)2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35564234

RESUMO

Optical biosensors based on localized surface plasmon resonance (LSPR) are the future of label-free detection methods. This work reports the development of plasmonic thin films, containing Au nanoparticles dispersed in a TiO2 matrix, as platforms for LSPR biosensors. Post-deposition treatments were employed, namely annealing at 400 °C, to develop an LSPR band, and Ar plasma, to improve the sensitivity of the Au-TiO2 thin film. Streptavidin and biotin conjugated with horseradish peroxidase (HRP) were chosen as the model receptor-analyte, to prove the efficiency of the immobilization method and to demonstrate the potential of the LSPR-based biosensor. The Au-TiO2 thin films were activated with O2 plasma, to promote the streptavidin immobilization as a biorecognition element, by increasing the surface hydrophilicity (contact angle drop to 7°). The interaction between biotin and the immobilized streptavidin was confirmed by the detection of HRP activity (average absorbance 1.9 ± 0.6), following a protocol based on enzyme-linked immunosorbent assay (ELISA). Furthermore, an LSPR wavelength shift was detectable (0.8 ± 0.1 nm), resulting from a plasmonic thin-film platform with a refractive index sensitivity estimated to be 33 nm/RIU. The detection of the analyte using these two different methods proves that the functionalization protocol was successful and the Au-TiO2 thin films have the potential to be used as an LSPR platform for label-free biosensors.

13.
J Sports Med Phys Fitness ; 62(1): 19-24, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33586936

RESUMO

BACKGROUND: This study investigated the relationship between the lactate minimum (LACmin) and the 10- (T10) and 30-min (T30) continuous tests in swimmers. METHODS: Twelve swimmers (78.1±3.1% of the world record) performed the LACmin (hyperlactatemia: 2×50 m all-out 8-min apart, incremental part: N.×300 m 30-s apart), T30 and T10 using the front-crawl stroke. Blood samples were collected after each stage of LACmin for lactate analysis. Swimmers were oriented to swim as fast and as constant as possible in T10 and T30. RESULTS: Speeds in T10 (1.28±0.10 m/s) and T30 (1.21±0.09 m/s) were different from LACmin (1.24±0.09 m/s). T10 and T30 speeds presented a nearly perfect relationship with LACmin and acceptable prediction errors (T10: r=0.938, P<0.001, 0.033 m/s; T30: r=0.927, P<0.001, 0.036 m/s, respectively). CONCLUSIONS: T10 and T30 can be used as indirect tests for evaluating LACmin in swimming.


Assuntos
Ácido Láctico , Natação
15.
Artigo em Inglês | MEDLINE | ID: mdl-33468460

RESUMO

There is an increasing need for novel drugs and new strategies for the therapy of invasive candidiasis. This study aimed to develop and characterize liposome-based nanoparticles of carvacrol, cinnamaldehyde, citral, and thymol with anti-Candida activities. Dioctadecyldimethylammonium bromide- and monoolein-based liposomes in a 1:2 molar ratio were prepared using a lipid-film hydration method. Liposomes were assembled with equal volumes of liposomal stock dispersion and stock solutions of carvacrol, cinnamaldehyde, citral, or thymol in dimethyl sulfoxide. Cytotoxicity was tested on RAW 264.7 macrophages. In vitro antifungal activity of liposomes with phytocompounds was evaluated according to European Committee on Antimicrobial Susceptibility Testing (EUCAST) methodology using clinical isolates of Candida albicans, Candida auris, Candida dubliniensis, and Candida tropicalis Finally, the ability of macrophage cells to kill Candida isolates after addition of phytocompounds and their nanoparticles was determined. Nanoparticles with 64 µg/ml of cinnamaldehyde, 256 µg/ml of citral, and 128 µg/ml of thymol had the best characteristics among the formulations tested. The highest encapsulation efficiencies were achieved with citral (78% to 83%) and carvacrol (66% to 71%) liposomes. Carvacrol and thymol in liposome-based nanoparticles were nontoxic regardless of the concentration. Moreover, carvacrol and thymol maintained their antifungal activity after encapsulation, and there was a significant reduction (∼41%) of yeast survival when macrophages were incubated with carvacrol or thymol liposomes. In conclusion, carvacrol and thymol liposomes possess high stability, low cytotoxicity, and antifungal activity that act synergistically with macrophages.


Assuntos
Candida , Timol , Acroleína/análogos & derivados , Monoterpenos Acíclicos , Antifúngicos/farmacologia , Cimenos , Glicerídeos , Lipossomos , Testes de Sensibilidade Microbiana , Monoterpenos/farmacologia , Timol/farmacologia
16.
Res Sports Med ; 29(6): 598-604, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33307810

RESUMO

To describe the pacing pattern of elite 400 m freestyle swimmers, understand how athletes select the first half compared to their 200-m race pace, and correlate critical speed (CS) and D' with pacing parameters. The best all-time 400 m performances were obtained, and 200 m performances were retrieved from the same competition. Twenty-four performances were selected and, when possible, 50 m-splits were obtained. CS and D' were calculated based on the 200 m and 400 m performances. Most athletes adopted a parabolic pacing pattern. Performance in the 400 m correlated with that of the 200 m (rho = 0.418, p = 0.042), the % difference between 200 m performance and 200 m split correlated with CS (rho = -0.595, p = 0.002) and with D' (rho = 0.808, p < 0.001). The correlation between D' and % difference between average speed and CS was nearly perfect (rho = 1.000, p < 0.001). Recommendations of having the first half of the 400 m 4-5 s slower than their 200 m race do not seem to be appropriate for all swimmers and depends on physiological abilities.


Assuntos
Desempenho Atlético/fisiologia , Desempenho Atlético/psicologia , Comportamento Competitivo/fisiologia , Resistência Física/fisiologia , Natação/fisiologia , Natação/psicologia , Humanos , Masculino
17.
Parasitol Int ; 80: 102239, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33157242

RESUMO

High-throughput profiling of metabolites has been used to identify metabolic changes in murine models as a response to the infection by the parasitic trematode Schistosoma. These investigations have contributed to our understanding on the pathogenesis of this tropical neglected disease, with a potential of helping diagnosis. Here, our study aimed to investigate the application of gas chromatography-mass spectrometry (GC/MS) on the profiling of urine metabolites from mice carrying infections by Schistosoma mansoni. Two larval infection doses created distinctive infection intensities in mice, whereby the heavily infected animals were found to release 25 times more eggs in faeces than lightly infected animals. Over 200 urine metabolites were identified from these animals by GC/MS, following two complementary derivatisation methods. A list of 14 individual metabolites with altered relative abundances between groups were identified. Most of the altered metabolites showed a trend of increased abundances in response to infection intensity, indicating host-specific metabolic alterations as a result of the disease. Hippurate, a metabolite which concentration is intimately modulated by the gut microbiota, was found to be highly correlated to infection intensity. Our study showed that urine metabolic profiling by GC/MS can distinguish non-infected animals from those carrying light and heavy infections by S. mansoni, revealing metabolites associated to the infection and providing insights on the pathogenesis of schistosomiasis.


Assuntos
Metabolômica/métodos , Schistosoma mansoni/fisiologia , Esquistossomose mansoni/metabolismo , Urina/química , Animais , Fezes/parasitologia , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Camundongos , Camundongos Endogâmicos BALB C
18.
J Sports Med Phys Fitness ; 61(1): 152-158, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33092334

RESUMO

This study describes the changes in selected points of the speed curve, stroke rate (SR), and stroke length (SL) of an elite butterfly swimmer and examines their relationship with average speed (AS) and competitive performance. Over eight years, a male swimmer (50 and 100 m: 22.70 and 51.47 s) underwent 18 tests to assess AS, SR, SL, intracyclic speed variation (ISV), and eight selected points of the speed curve. Peak1 is the maximum speed in the upward kick executed during the arm recovery; peak2 is the maximum speed in the first downward kick after the arm entered into the water; peak3 is the maximum speed during the arm pull; and peak4 is the maximum speed during the arm push combined with the second downward kick. Min1, min2, min3, min4 corresponds to the minimum speeds found respectively before each peak speed. Official competitive results in 50 (50BF) and 100 m (100BF) within three weeks of the speed tests were registered. SR (r=0.736), ISV (r=-0.493), peak1 (r=0.555), min2 (r=0.558), and min3 (r=0.539) were correlated with AS. 50BF was correlated with AS (r=-0.658) and peak1 (r=-0.820), whereas 100BF with AS (r=-0.676), SR (r=-0.571), peak1 (r=-0.758), and peak2 (r=-0.594). AS increased by improving SR, peak1 and peak3. Increases in min2 and min3 indicate better transitions from resistive to propulsive phases. Selected points of the speed curve may predict butterfly performance.


Assuntos
Natação , Animais , Braço , Desempenho Atlético , Fenômenos Biomecânicos , Humanos , Masculino
19.
Int J Parasitol ; 50(14): 1145-1155, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32822680

RESUMO

Trichomonas vaginalis is a protozoan parasite that causes trichomoniasis, the most prevalent non-viral sexually transmitted infection worldwide. Trichomonas vaginalis releases extracellular vesicles that play a role in parasite:parasite and parasite:host interactions. The aim of this study was to characterise the RNA cargo of these vesicles. Trichomonas vaginalis extracellular vesicles were found to encapsulate a cargo of RNAs of small size. RNA-seq analysis showed that tRNA-derived small RNAs, mostly 5' tRNA halves, are the main type of small RNA in these vesicles. The tRNA-derived small RNAs in T. vaginalis extracellular vesicles were shown to be derived from the specific processing of tRNAs within cells. The specificity of this RNA cargo in T. vaginalis extracellular vesicles suggests a preference for packaging. The RNA cargo of T. vaginalis was shown to be rapidly internalised by human cells via lipid raft-dependent endocytosis. The potential role of these tsRNAs - an emerging class of small RNAs with regulatory functions - on altering host cellular responses requires further examination, suggesting a new mode of parasite:host communication.


Assuntos
Vesículas Extracelulares , RNA de Protozoário , RNA de Transferência , Trichomonas vaginalis , Animais , Endocitose , Humanos , Tricomoníase , Trichomonas vaginalis/genética
20.
BMC Mol Cell Biol ; 21(1): 54, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32689943

RESUMO

BACKGROUND: Trichomonas vaginalis, the causative agent of a prevalent urogenital infection in humans, is an evolutionarily divergent protozoan. Protein-coding genes in T. vaginalis are largely controlled by two core promoter elements, producing mRNAs with short 5' UTRs. The specific mechanisms adopted by T. vaginalis to fine-tune the translation efficiency (TE) of mRNAs remain largely unknown. RESULTS: Using both computational and experimental approaches, this study investigated two key factors influencing TE in T. vaginalis: codon usage and mRNA secondary structure. Statistical dependence between TE and codon adaptation index (CAI) highlighted the impact of codon usage on mRNA translation in T. vaginalis. A genome-wide interrogation revealed that low structural complexity at the 5' end of mRNA followed closely by a highly structured downstream region correlates with TE variation in this organism. To validate these findings, a synthetic library of 15 synonymous iLOV genes was created, representing five mRNA folding profiles and three codon usage profiles. Fluorescence signals produced by the expression of these synonymous iLOV genes in T. vaginalis were consistent with and validated our in silico predictions. CONCLUSIONS: This study demonstrates the role of codon usage bias and mRNA secondary structure in TE of T. vaginalis mRNAs, contributing to a better understanding of the factors that influence, and possibly regulate, gene expression in this human pathogen.


Assuntos
Evolução Biológica , Biossíntese de Proteínas , Trichomonas vaginalis/genética , Sequência de Bases , Códon/genética , Biblioteca Gênica , Genes Reporter , Conformação de Ácido Nucleico , Fases de Leitura Aberta/genética , RNA Mensageiro/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
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