283 research outputs found
Convolutional Neural Network Applied to SARS-CoV-2 Sequence Classification
COVID-19, the illness caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus belonging to the Coronaviridade family, a single-strand positive-sense RNA genome, has been spreading around the world and has been declared a pandemic by the World Health Organization. On 17 January 2022, there were more than 329 million cases, with more than 5.5 million deaths. Although COVID-19 has a low mortality rate, its high capacities for contamination, spread, and mutation worry the authorities, especially after the emergence of the Omicron variant, which has a high transmission capacity and can more easily contaminate even vaccinated people. Such outbreaks require elucidation of the taxonomic classification and origin of the virus (SARS-CoV-2) from the genomic sequence for strategic planning, containment, and treatment of the disease. Thus, this work proposes a high-accuracy technique to classify viruses and other organisms from a genome sequence using a deep learning convolutional neural network (CNN). Unlike the other literature, the proposed approach does not limit the length of the genome sequence. The results show that the novel proposal accurately distinguishes SARS-CoV-2 from the sequences of other viruses. The results were obtained from 1557 instances of SARS-CoV-2 from the National Center for Biotechnology Information (NCBI) and 14,684 different viruses from the Virus-Host DB. As a CNN has several changeable parameters, the tests were performed with forty-eight different architectures; the best of these had an accuracy of 91.94 +/- 2.62% in classifying viruses into their realms correctly, in addition to 100% accuracy in classifying SARS-CoV-2 into its respective realm, Riboviria. For the subsequent classifications (family, genera, and subgenus), this accuracy increased, which shows that the proposed architecture may be viable in the classification of the virus that causes COVID-19.Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)High-Performance Computing Center at UFRN(NPAD/UFRN
Biocomposite for Prolonged Release of Water-Soluble Drugs
This study aimed to develop a prolonged-release system based on palygorskite and chitosan,
which are natural ingredients widely available, affordable, and accessible. The chosen model drug
was ethambutol (ETB), a tuberculostatic drug with high aqueous solubility and hygroscopicity, which
is incompatible with other drugs used in tuberculosis therapy. The composites loaded with ETB were
obtained using different proportions of palygorskite and chitosan through the spray drying technique.
The main physicochemical properties of the microparticles were determined using XRD, FTIR, thermal
analysis, and SEM. Additionally, the release profile and biocompatibility of the microparticles were
evaluated. As a result, the chitosan–palygorskite composites loaded with the model drug appeared
as spherical microparticles. The drug underwent amorphization within the microparticles, with
an encapsulation efficiency greater than 84%. Furthermore, the microparticles exhibited prolonged
release, particularly after the addition of palygorskite. They demonstrated biocompatibility in an
in vitro model, and their release profile was influenced by the proportion of inputs in the formulation.
Therefore, incorporating ETB into this system offers improved stability for the administered product
in the initial tuberculosis pharmacotherapy dose, minimizing its contact with other tuberculostatic
agents in the treatment, as well as reducing its hygroscopicityCoordenação de Aperfeiçoamento de Pessoal de
NÃvel Superior-Brazil (CAPES)—Process n 88887.131333/2016-00
Lipid-polymeric films: composition, production and applications in wound healing and skin repair
The use of lipids in the composition of polymeric-based films for topical administration of bioactive ingredients is a recent research topic; while few products are commercially available, films containing lipids represent a strategic area for the development of new products. Some lipids are usually used in polymeric-based film formulations due to their plasticizing action, with a view to improving the mechanical properties of these films. On the other hand, many lipids have healing, antimicrobial, anti-inflammatory, anti-aging properties, among others, that make them even more interesting for application in the medical-pharmaceutical field. This manuscript discusses the production methods of these films both on a laboratory and at industrial scales, the properties of the developed biopolymers, and their advantages for the development of dermatologic and cosmetic products.This research was funded by the Portuguese Science and Technology Foundation (FCT/MCT) and European Funds (PRODER/COMPETE), under the project reference UIDB/04469/2020 (strategic fund), co-financed by FEDER, under the Partnership Agreement PT2020.info:eu-repo/semantics/publishedVersio
Genome-wide diversity and differentiation in New World populations of the human malaria parasite Plasmodium vivax.
BACKGROUND: The Americas were the last continent colonized by humans carrying malaria parasites. Plasmodium falciparum from the New World shows very little genetic diversity and greater linkage disequilibrium, compared with its African counterparts, and is clearly subdivided into local, highly divergent populations. However, limited available data have revealed extensive genetic diversity in American populations of another major human malaria parasite, P. vivax. METHODS: We used an improved sample preparation strategy and next-generation sequencing to characterize 9 high-quality P. vivax genome sequences from northwestern Brazil. These new data were compared with publicly available sequences from recently sampled clinical P. vivax isolates from Brazil (BRA, total n = 11 sequences), Peru (PER, n = 23), Colombia (COL, n = 31), and Mexico (MEX, n = 19). PRINCIPAL FINDINGS/CONCLUSIONS: We found that New World populations of P. vivax are as diverse (nucleotide diversity π between 5.2 × 10-4 and 6.2 × 10-4) as P. vivax populations from Southeast Asia, where malaria transmission is substantially more intense. They display several non-synonymous nucleotide substitutions (some of them previously undescribed) in genes known or suspected to be involved in antimalarial drug resistance, such as dhfr, dhps, mdr1, mrp1, and mrp-2, but not in the chloroquine resistance transporter ortholog (crt-o) gene. Moreover, P. vivax in the Americas is much less geographically substructured than local P. falciparum populations, with relatively little between-population genome-wide differentiation (pairwise FST values ranging between 0.025 and 0.092). Finally, P. vivax populations show a rapid decline in linkage disequilibrium with increasing distance between pairs of polymorphic sites, consistent with very frequent outcrossing. We hypothesize that the high diversity of present-day P. vivax lineages in the Americas originated from successive migratory waves and subsequent admixture between parasite lineages from geographically diverse sites. Further genome-wide analyses are required to test the demographic scenario suggested by our data
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Urinary incontinence related to perineal muscle strength in the first trimester of pregnancy: cross-sectional study
Objective To analyze pelvic floor muscle strength (PFMS), urinary continence and quality of life related to urinary incontinence (UI) of women in the first trimester of pregnancy. Method Cross-sectional study with a sample of 500 women who started prenatal care in a complementary healthcare facility in Guarulhos, state of São Paulo, from 2012 and 2013. Pelvic floor muscle strength was evaluated through perineometry. The pregnant women who presented UI answered the International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF). Results It was found that maternal age (OR=1.06; CI95% 1.02-1.11) and prior UI (OR=15.12; 95%CI 8.19-27.92) are the variables that, in tandem, best explain the occurrence of UI at the beginning of pregnancy. The mean score on the ICIQ-SF was 8.2 (SD=3.9), considered a moderate impact on quality of life. Conclusion Older pregnant women with prior UI are more likely to have UI in the first trimester of pregnancy.
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Constitutive RB1 mutation in a child conceived by in vitro fertilization: implications for genetic counseling
<p>Abstract</p> <p>Background</p> <p>The purpose of this study was to identify mutations associated with bilateral retinoblastoma in a quadruplet conceived by in vitro fertilization, and to trace the parental origin of mutations in the four quadruplets and their father.</p> <p>Methods</p> <p>Mutational screening was carried out by sequencing. Genotyping was carried out for determining quadruplet zygosity.</p> <p>Results</p> <p>The proband was a carrier of a novel <it>RB1</it> constitutive mutation (g.2056C>G) which was not detected in her father or her unaffected sisters, and of two other mutations (g.39606 C>T and g.174351T>A) also present in two monozygotic sisters. The novel mutation probably occurred de novo while the others were of likely maternal origin. The novel mutation, affecting the Kozak consensus at the 5'UTR of <it>RB1</it> and g.174351T>A were likely associated to retinoblastoma in the proband.</p> <p>Conclusion</p> <p>Molecular diagnosis of retinoblastoma requires genotypic data of the family for determining hereditary transmission. In the case of children generated by IVF with oocytes from an anonymous donor which had been stored in a cell repository, this might not be successfully accomplished, making precise diagnosis impracticable for genetic counseling.</p
Arte, escola e museu: análise de uma experiência em arte/educação no Museu Universitário de Arte - MUnA
Resumo A partir de uma perspectiva teórica e empÃrica, o artigo analisa uma experiência em arte/educação desenvolvida com estudantes da rede pública de ensino na cidade de Uberlândia, Minas Gerais, no Museu Universitário de Arte - MUnA. De abordagem qualitativa e de caráter descritivo e interpretativo, a pesquisa constatou que o contato com museu de arte possibilita ao estudante não apenas ampliar o seu conhecimento de mundo, mas enriquecer sua formação cultural e melhorar a sua capacidade de expressão, além de possibilitar aos estudantes uma melhor interação com o meio social em que vivem. O conhecimento em arte é um aprendizado que começa na observação de uma obra de arte, da sua leitura e da prática artÃstica. As leituras e comportamentos que cada estudante tem ao apreciar uma obra de arte estão relacionados à sua experiência com diferentes manifestações artÃsticas. É indispensável que escolas, professores de arte e ações educativas em museus sejam importantes mediadores para a produção do conhecimento em arte aos estudantes. Construir esse conhecimento a partir do acesso constante a esses espaços artÃsticos e educacionais, além do desenvolvimento de atividades artÃsticas nesses espaços, possibilita ao estudante elevar a sua compreensão da cultura nacional. Verificamos, ainda, que os estudantes produziram trabalhos artÃsticos significativos durante a ação educativa no museu, o que contribuiu para que ampliassem sua experiência com a arte
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