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1.
Sci Rep ; 14(1): 10094, 2024 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-38698200

RESUMEN

Intramuscular fat (IMF) and backfat thickness (BFT) are critical economic traits impacting meat quality. However, the genetic variants controlling these traits need to be better understood. To advance knowledge in this area, we integrated RNA-seq and single nucleotide polymorphisms (SNPs) identified in genomic and transcriptomic data to generate a linkage disequilibrium filtered panel of 553,581 variants. Expression quantitative trait loci (eQTL) analysis revealed 36,916 cis-eQTLs and 14,408 trans-eQTLs. Association analysis resulted in three eQTLs associated with BFT and 24 with IMF. Functional enrichment analysis of genes regulated by these 27 eQTLs revealed noteworthy pathways that can play a fundamental role in lipid metabolism and fat deposition, such as immune response, cytoskeleton remodeling, iron transport, and phospholipid metabolism. We next used ATAC-Seq assay to identify and overlap eQTL and open chromatin regions. Six eQTLs were in regulatory regions, four in predicted insulators and possible CCCTC-binding factor DNA binding sites, one in an active enhancer region, and the last in a low signal region. Our results provided novel insights into the transcriptional regulation of IMF and BFT, unraveling putative regulatory variants.


Asunto(s)
Cromatina , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Animales , Bovinos , Cromatina/genética , Cromatina/metabolismo , Tejido Adiposo/metabolismo , Mutación , Desequilibrio de Ligamiento , Estudio de Asociación del Genoma Completo , Regulación de la Expresión Génica , Metabolismo de los Lípidos/genética
2.
PLoS One ; 19(4): e0295318, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38652713

RESUMEN

INTRODUCTION: Burns are tissue traumas caused by energy transfer and occur with a variable inflammatory response. The consequences of burns represent a public health problem worldwide. Inhalation injury (II) is a severity factor when associated with burn, leading to a worse prognosis. Its treatment is complex and often involves invasive mechanical ventilation (IMV). The primary purpose of this study will be to assess the evidence regarding the frequency and mortality of II in burn patients. The secondary purposes will be to assess the evidence regarding the association between IIs and respiratory complications (pneumonia, airway obstruction, acute respiratory failure, acute respiratory distress syndrome), need for IMV and complications in other organ systems, and highlight factors associated with IIs in burn patients and prognostic factors associated with acute respiratory failure, need for IMV and mortality of II in burn patients. METHODS: This is a systematic literature review and meta-analysis, according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA). PubMed/MEDLINE, Embase, LILACS/VHL, Scopus, Web of Science, and CINAHL databases will be consulted without language restrictions and publication date. Studies presenting incomplete data and patients under 19 years of age will be excluded. Data will be synthesized through continuous (mean and standard deviation) and dichotomous (relative risk) variables and the total number of participants. The means, sample sizes, standard deviations from the mean, and relative risks will be entered into the Review Manager web analysis software (The Cochrane Collaboration). DISCUSSION: Despite the extensive experience managing IIs in burn patients, they still represent an important cause of morbidity and mortality. Diagnosis and accurate measurement of its damage are complex, and therapies are essentially based on supportive measures. Considering the challenge, their impact, and their potential severity, IIs represent a promising area for research, needing further studies to understand and contribute to its better evolution. The protocol of this review is registered on the International prospective register of systematic reviews platform of the Center for Revisions and Disclosure of the University of York, United Kingdom (https://www.crd.york.ac.uk/prospero), under number RD42022343944.


Asunto(s)
Quemaduras , Metaanálisis como Asunto , Revisiones Sistemáticas como Asunto , Humanos , Quemaduras/mortalidad , Quemaduras/complicaciones , Respiración Artificial/efectos adversos , Quemaduras por Inhalación/complicaciones , Quemaduras por Inhalación/mortalidad , Quemaduras por Inhalación/terapia , Pronóstico , Lesión por Inhalación de Humo/complicaciones , Lesión por Inhalación de Humo/mortalidad
3.
J Clin Neurosci ; 124: 1-14, 2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38615371

RESUMEN

BACKGROUND: Vestibular schwannomas (VS) are benign tumors arising from vestibular nerve's Schwann cells. Surgical resection via retrosigmoid (RS) or middle fossa (MF) is standard, but the optimal approach remains debated. This meta-analysis evaluated RS and MF approaches for VS management, emphasizing hearing preservation and Cranial nerve seven (CN VII) outcomes stratified by tumor size. METHODS: Systematic searches across PubMed, Cochrane, Web of Science, and Embase identified relevant studies. Hearing and CN VII outcomes were gauged using the American Academy of Otolaryngology-Head and Neck Surgery, Gardner Robertson, and House-Brackmann scores. RESULTS: Among 7228 patients, 56 % underwent RS and 44 % MF. For intracanalicular tumors, MF recorded 38 % hearing loss, compared to RS's 54 %. In small tumors (<1.5 cm), MF showed 41 % hearing loss, contrasting RS's lower 15 %. Medium-sized tumors (1.5 cm-2.9 cm) revealed 68 % hearing loss in MF and 55 % in RS. Large tumors (>3cm) were only reported in RS with a hearing loss rate of 62 %. CONCLUSION: Conclusively, while MF may be preferable for intracanalicular tumors, RS demonstrated superior hearing preservation for small to medium-sized tumors. This research underlines the significance of stratified outcomes by tumor size, guiding surgical decisions and enhancing patient outcomes.

4.
Mikrochim Acta ; 191(4): 197, 2024 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-38483622

RESUMEN

A fully reusable electrochemical device is proposed for the first time made from laser cutting and a homemade conductive ink composed of carbon and nail polish. As a sensor substrate, we applied polymethyl methacrylate, which allows the surface to be renewed by simply removing and reapplying a new layer of ink. In addition to the ease of renewing the sensor's conductive surface, the design of the device has allowed for the integration of different forms of analysis. The determination of L-Dopa was performed using DPV, which presented a linear response range between 5.0 and 1000.0 µmol L-1, and a LOD of 0.11 µmol L-1. For dopamine, a flow injection analysis system was employed, and using the amperometric technique measurements were performed with a linear ranging from 2.0 to 100.0 µmol L-1 and a LOD of 0.26 µmol L-1. To demonstrate its applicability, the device was used in the quantification of analytes in pharmaceutical drug and synthetic urine samples.


Asunto(s)
Grafito , Levodopa , Levodopa/análisis , Dopamina/análisis , Técnicas Electroquímicas/métodos , Electrodos , Reproducibilidad de los Resultados
5.
Anal Methods ; 16(15): 2256-2266, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38517319

RESUMEN

A conductive nanocomposite consisting of heparin-stabilized gold nanoparticles embedded in graphene was prepared and characterized to develop an electrochemical sensor for the determination of esculetin in tea and jam samples. The gold nanoparticles were characterized by spectroscopic and microscopic techniques. The different proportions of graphene in the nanocomposite were evaluated and characterized by electrochemical practices. The heterostructure material on the glassy carbon electrode with esculetin showed π-π stacking interactions with an adsorption-controlled process. The voltammetric profile of esculetin using the proposed nanomaterial presented oxidation and reduction peaks at +0.61 and +0.58 V vs. Ag/AgCl, respectively, facilitating the electron transfer with esculetin through the transfer of two moles of protons and two moles of electrons per mole of esculetin. Using optimized conditions and square wave voltammetry, the calibration curve was obtained with two linear ranges, from 0.1 to 20.5 µmol L-1, with a detection limit of 43.0 nmol L-1. The electrochemical sensor showed satisfactory results for repeatability and stability, although interferences were observed in the presence of high concentrations of ascorbic acid or quercetin. The sensor was successfully applied in the determination of esculetin in samples of mulberry jam, white mulberry leaf tea, and white mulberry powder tea, presenting adequate recovery ranges. This directive provides valuable insights for the development of novel electrochemical sensors using heparin-based conductive nanomaterials with improved sensitivity and sensibility.


Asunto(s)
Grafito , Nanopartículas del Metal , Topos , Umbeliferonas , Animales , Grafito/química , Oro/química , Heparina , Nanopartículas del Metal/química ,
6.
Int J Clin Oncol ; 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38528294

RESUMEN

BACKGROUND: Cancer of unknown primary site (CUP) is a heterogeneous group of tumors for which the origin remains unknown. Clinical outcomes might be influenced by regulatory processes in its microenvironment. Microsatellite instability (MSI) is a predictive biomarker for cancer immunotherapy and its status, as well as co-occurrence with PD-L1 expression, is poorly evaluated. We aim to evaluate the expression of PD-L1 and the status of MSI in CUP and their possible associations with clinical-pathological features. METHODS: The combined positive score (CPS) PD-L1 expression was evaluated by immunohistochemistry. MSI status was assessed using a hexa-plex marker panel by polymerase chain reaction followed by fragment analysis. RESULTS: Among the 166 cases, MSI analysis was conclusive in 120, with two cases being MSI positive (1.6%). PD-L1 expression was positive in 18.3% of 109 feasible cases. PD-L1 expression was significantly associated with non-visceral metastasis and a dominance of nodal metastasis. The median overall survival (mOS) was 3.7 (95% CI 1.6-5.8) months and patients who expressed PD-L1 achieved a better mOS compared to those who did not express PD-L1 (18.7 versus 3.0 months, p-value: < .001). ECOG-PS equal to or more than two and PD-L1 expression were independent prognostic factors in multivariate analysis (2.37 and 0.42, respectively). CONCLUSION: PD-L1 is expressed in a subset (1/5) of patients with CUP and associated with improved overall survival, while MSI is a rare event. There is a need to explore better the tumor microenvironment as well as the role of immunotherapy to change such a bad clinical outcome.

7.
Cell Host Microbe ; 32(3): 304-314.e8, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38417443

RESUMEN

Several vaccines targeting bacterial pathogens show reduced efficacy upon concurrent viral infection, indicating that a new vaccinology approach is required. To identify antigens for the human pathogen Streptococcus pneumoniae that are effective following influenza infection, we performed CRISPRi-seq in a murine model of superinfection and identified the conserved lafB gene as crucial for virulence. We show that LafB is a membrane-associated, intracellular protein that catalyzes the formation of galactosyl-glucosyl-diacylglycerol, a glycolipid important for cell wall homeostasis. Respiratory vaccination with recombinant LafB, in contrast to subcutaneous vaccination, was highly protective against S. pneumoniae serotypes 2, 15A, and 24F in a murine model. In contrast to standard capsule-based vaccines, protection did not require LafB-specific antibodies but was dependent on airway CD4+ T helper 17 cells. Healthy human individuals can elicit LafB-specific immune responses, indicating LafB antigenicity in humans. Collectively, these findings present a universal pneumococcal vaccine antigen that remains effective following influenza infection.


Asunto(s)
Vacunas contra la Influenza , Gripe Humana , Infecciones Neumocócicas , Sobreinfección , Humanos , Animales , Ratones , Streptococcus pneumoniae , Infecciones Neumocócicas/prevención & control , Infecciones Neumocócicas/microbiología , Serogrupo , Células Th17 , Gripe Humana/prevención & control , Modelos Animales de Enfermedad , Vacunas Neumococicas , Antígenos Bacterianos/genética , Anticuerpos Antibacterianos
8.
Int J Biol Macromol ; 263(Pt 1): 130111, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38346614

RESUMEN

Sugarcane bagasse was pretreated with dilute phosphoric acid or sulfuric acid to facilitate cellulose hydrolysis and lignin extraction. With phosphoric acid, only 8 % of the initial cellulose was lost after delignification, whereas pretreatment with sulfuric acid resulted in the solubilization of 38 % of the initial cellulose. After enzymatic hydrolysis, the process using phosphoric acid produced approximately 35 % more glucose than that using sulfuric acid. In general, the lignins showed 95-97 % purity (total lignin, w/w), an average molar mass of 9500-10,200 g mol-1, a glass transition temperature of 140-160 °C, and a calorific value of 25 MJ kg-1. Phosphoric acid lignin (PAL) was slightly more polar than sulfuric acid lignin (SAL). PAL had 13 % more oxidized units and 20 % more OH groups than SAL. Regardless of the acid used, the lignins shared similar properties, but differed slightly in the characteristics of their functional groups and chemical bonds. These findings show that pretreatment catalyzed with either of the two acids resulted in lignin with sufficiently good characteristics for use in industrial processes.


Asunto(s)
Celulosa , Saccharum , Celulosa/química , Lignina/química , Saccharum/química , Hidrólisis , Ácidos Fosfóricos , Ácidos Sulfúricos
9.
Metab Brain Dis ; 39(4): 577-587, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38305999

RESUMEN

Atypical parkinsonism (AP) is a group of complex neurodegenerative disorders with marked clinical and pathophysiological heterogeneity. The use of systems biology tools may contribute to the characterization of hub-bottleneck genes, and the identification of its biological pathways to broaden the understanding of the bases of these disorders. A systematic search was performed on the DisGeNET database, which integrates data from expert curated repositories, GWAS catalogues, animal models and the scientific literature. The tools STRING 11.0 and Cytoscape 3.8.2 were used for analysis of protein-protein interaction (PPI) network. The PPI network topography analyses were performed using the CytoHubba 0.1 plugin for Cytoscape. The hub and bottleneck genes were inserted into 4 different sets on the InteractiveVenn. Additional functional enrichment analyses were performed to identify Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways and gene ontology for a described set of genes. The systematic search in the DisGeNET database identified 485 genes involved with Atypical Parkinsonism. Superimposing these genes, we detected a total of 31 hub-bottleneck genes. Moreover, our functional enrichment analyses demonstrated the involvement of these hub-bottleneck genes in 3 major KEGG pathways. We identified 31 highly interconnected hub-bottleneck genes through a systems biology approach, which may play a key role in the pathogenesis of atypical parkinsonism. The functional enrichment analyses showed that these genes are involved in several biological processes and pathways, such as the glial cell development, glial cell activation and cognition, pathways were related to Alzheimer disease and Parkinson disease. As a hypothesis, we highlight as possible key genes for AP the MAPT (microtubule associated protein tau), APOE (apolipoprotein E), SNCA (synuclein alpha) and APP (amyloid beta precursor protein) genes.


Asunto(s)
Redes y Vías Metabólicas , Trastornos Parkinsonianos , Mapas de Interacción de Proteínas , Biología de Sistemas , Humanos , Trastornos Parkinsonianos/genética , Trastornos Parkinsonianos/metabolismo , Redes y Vías Metabólicas/genética , Mapas de Interacción de Proteínas/genética , Redes Reguladoras de Genes/genética , Animales
10.
J Clin Monit Comput ; 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38381360

RESUMEN

Perfusion Computed Tomography (PCT) is an alternative tool to assess cerebral hemodynamics during trauma. As acute traumatic subdural hematomas (ASH) is a severe primary injury associated with poor outcomes, the aim of this study was to evaluate the cerebral hemodynamics in this context. Five adult patients with moderate and severe traumatic brain injury (TBI) and ASH were included. All individuals were indicated for surgical evacuation. Before and after surgery, PCT was performed and cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) were evaluated. These parameters were associated with the outcome at 6 months post-trauma with the extended Glasgow Outcome Scale (GOSE). Mean age of population was 46 years (SD: 8.1). Mean post-resuscitation Glasgow coma scale (GCS) was 10 (SD: 3.4). Mean preoperative midline brain shift was 10.1 mm (SD: 1.8). Preoperative CBF and MTT were 23.9 ml/100 g/min (SD: 6.1) and 7.3 s (1.3) respectively. After surgery, CBF increase to 30.7 ml/100 g/min (SD: 5.1), and MTT decrease to 5.8s (SD:1.0), however, both changes don't achieve statistically significance (p = 0.06). Additionally, CBV increase after surgery, from 2.34 (SD: 0.67) to 2.63 ml/100 g (SD: 1.10), (p = 0.31). Spearman correlation test of postoperative and preoperative CBF ratio with outcome at 6 months was 0.94 (p = 0.054). One patient died with the highest preoperative MTT (9.97 s) and CBV (4.51 ml/100 g). CBF seems to increase after surgery, especially when evaluated together with the MTT values. It is suggested that the improvement in postoperative brain hemodynamics correlates to favorable outcome.

11.
Int J Cardiovasc Imaging ; 40(4): 745-756, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38277026

RESUMEN

COVID-19 may have residual consequences in multiple organs, including the cardiovascular system. The purpose of the present investigation is to quantify myocardial function in symptomatic individuals with long COVID and investigate the association between illness severity and myocardial function. A retrospective cross-sectional study was conducted in which symptomatic individuals with previous COVID-19 underwent echocardiographic analysis of left ventricle global longitudinal strain (LVGLS) and myocardial work (MW). Individuals also performed cardiopulmonary testing (CPX) to assess peak oxygen uptake (VO2peak). Differences between illness severity subgroups were analyzed by the Mann-Whitney test. Correlations were calculated using the Spearman correlation test. Multilinear regressions were performed to evaluate the influences of COVID-19 severity, body mass index, age, and sex on MW. Fifty-six individuals were included (critical subgroup: 17; moderate/severe subgroup: 39), 59% females; median age: 56 years (IQR: 43-63). CPX revealed a substantial reduction in VO2peak (median of 53% of predicted values). LVGLS were not statistically different between subgroups. Global wasted work (GWW) was higher in the critical subgroup [146 (104-212) versus 121 (74-163) mmHg%, p = 0.01], and global work efficiency (GWE) was lower in this subgroup [93 (91-95) versus 94 (93-96), p = 0.03]. Illness severity was the only independent predictor of GWW and GWE (GWW: r2 = 0.167; p = 0.009; GWE: r2 = 0.172; p = 0.005) in multilinear regressions. In our study with long COVID-19 individuals, despite having a similar LVGLS, patients had subclinical LV dysfunction, demonstrated only by an increase in GWW and a decrease in GWE.


Asunto(s)
COVID-19 , Índice de Severidad de la Enfermedad , Humanos , COVID-19/complicaciones , COVID-19/diagnóstico , COVID-19/fisiopatología , Femenino , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estudios Transversales , Adulto , Ecocardiografía , Función Ventricular Izquierda , SARS-CoV-2 , Consumo de Oxígeno , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Izquierda/diagnóstico por imagen , Prueba de Esfuerzo
12.
J Strength Cond Res ; 38(2): 342-349, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37815258

RESUMEN

ABSTRACT: Santos da Silva, V, Nakamura, FY, Gantois, P, Nogueira Gouveia, JN, Peña, J, Beato, M, and Abade, E. Effects of upper-body and lower-body conditioning activities on postactivation performance enhancement during sprinting and jumping tasks in female soccer players. J Strength Cond Res 38(2): 342-349, 2024-This study aimed to investigate the postactivation performance enhancement (PAPE) effects of "specific" (half-back squat) and "nonspecific" (bench press) conditioning activities on sprinting and jumping performances in female soccer players. Fourteen players (mean ± SD : age = 22.3 ± 4.0 years; body mass = 60.2 ± 7.8 kg; height = 164.1 ± 4.2 cm) competing at national level (first League) participated in this within-subject crossover study. The players performed a warm-up protocol including 3 sets of 3 repetitions of half-back-squat or bench press exercises at 90% 1RM or a warm-up protocol without lifting weights (i.e., control condition). Forty-meter shuttle sprints (20 + 20 m with change of direction [COD-180°]), countermovement jump (CMJ), and horizontal jump (HJ) performances were recorded 6 minutes after the conditioning activities protocols or the control condition. Nonsignificant large positive effects were found for the HJ after the half-back-squat (ES = 1.68; p > 0.05) and bench press (ES = 1.68; p > 0.05) protocols. Although nonsignificant, HJ changes ( Δ = 0.07 m) were greater than the smallest worthwhile change (0.02 m) and standard error of measurement (0.03 m) after both conditioning activities. Moreover, no significant changes were found for sprint and CMJ performance after neither half-back-squat nor bench press protocols ( p > 0.05). In conclusion, both specific and nonspecific conditioning activities using heavy loads (i.e., 90% 1RM) may be suitable to enhance individual HJ. Finally, both conditioning activities are potentially ineffective for increasing sprint and CMJ performance in the context of this study.


Asunto(s)
Rendimiento Atlético , Carrera , Fútbol , Humanos , Femenino , Adolescente , Adulto Joven , Adulto , Fútbol/fisiología , Rendimiento Atlético/fisiología , Estudios Cruzados , Carrera/fisiología , Fuerza Muscular/fisiología
13.
J Health Psychol ; 29(2): 156-169, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37387357

RESUMEN

This study aimed to review the findings on body image (BI) dissatisfaction and muscle dysmorphia (MD) in Brazilian RT practitioners and the differences in the assessment tools used. A critical review of studies with searches in PubMed, Brazilian Virtual Health Library, SciELO, PsycInfo, and SPORTDiscus databases was conducted. A total of 23 studies were included. Nine tools were used to assess BI dissatisfaction or MD: three questionnaires and six visual scales. The overall mean BI dissatisfaction was 56.5% (59.2% in men vs 57.3% in women). The mean MD was 42.4% (45.1% in women vs 38.5% in men). BI dissatisfaction and MD are related to women seeking slimness and men wanting to increase muscle mass. In conclusion, the frequency of BI was high in both sexes, and MD, when identified, was higher in women. The scales and questionnaires used differ significantly in depth and scope for the same purpose.


Asunto(s)
Trastorno Dismórfico Corporal , Entrenamiento de Fuerza , Masculino , Humanos , Femenino , Imagen Corporal , Brasil , Emociones
14.
J Hazard Mater ; 465: 133285, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38154190

RESUMEN

Mining, a vital industry for economic growth, poses significant environmental pollution challenges. Failures in tailings dam containment have caused environmental contamination and raised concerns about preserving the globally significant biodiversity in the Atlantic Forest, which is under severe threat. Fruit-eating bats are key for forest regeneration as essential seed dispersers and pollinators. This study focuses on two keystone species, Artibeus lituratus and Sturnira lilium, exploring the effects of iron ore mining area (FEOA) and aluminum ore mining area (ALOA) on these bats, respectively, and comparing to individuals from a preserved Atlantic Forest fragment (FFA). Bats from FEOA showed higher Aluminum (Al), Calcium (Ca), Iron (Fe) and Barium (Ba) liver accumulation, as well as Ca and Fe muscle accumulation. These animals also showed higher liver and kidney oxidative damage associated with liver fibrosis and kidney inflammation. Brain and muscle also showed oxidative stress. Bats from ALOA showed higher Ca and Ba liver accumulation and Ca, Zinc (Zn), and Ba muscle accumulation, along with higher brain oxidative stress, liver fibrosis, and kidney inflammation. Our findings indicate that iron and aluminum ore mining activities cause adverse effects on bat tissues, posing a potential threat to biodiversity maintenance in the Atlantic Forest.


Asunto(s)
Quirópteros , Hierro , Humanos , Animales , Hierro/farmacología , Aluminio , Frutas , Bosques , Minería , Estrés Oxidativo , Contaminación Ambiental , Cirrosis Hepática , Inflamación
15.
Sci Adv ; 9(35): eadg9204, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37656782

RESUMEN

Despite the considerable morbidity and mortality of yellow fever virus (YFV) infections in Brazil, our understanding of disease outbreaks is hampered by limited viral genomic data. Here, through a combination of phylogenetic and epidemiological models, we reconstructed the recent transmission history of YFV within different epidemic seasons in Brazil. A suitability index based on the highly domesticated Aedes aegypti was able to capture the seasonality of reported human infections. Spatial modeling revealed spatial hotspots with both past reporting and low vaccination coverage, which coincided with many of the largest urban centers in the Southeast. Phylodynamic analysis unraveled the circulation of three distinct lineages and provided proof of the directionality of a known spatial corridor that connects the endemic North with the extra-Amazonian basin. This study illustrates that genomics linked with eco-epidemiology can provide new insights into the landscape of YFV transmission, augmenting traditional approaches to infectious disease surveillance and control.


Asunto(s)
Fiebre Amarilla , Virus de la Fiebre Amarilla , Humanos , Virus de la Fiebre Amarilla/genética , Filogenia , Brasil/epidemiología , Fiebre Amarilla/epidemiología , Brotes de Enfermedades , Genómica
16.
J Cheminform ; 15(1): 83, 2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37726842

RESUMEN

Generative models are frequently used for de novo design in drug discovery projects to propose new molecules. However, the question of whether or not the generated molecules can be synthesized is not systematically taken into account during generation, even though being able to synthesize the generated molecules is a fundamental requirement for such methods to be useful in practice. Methods have been developed to estimate molecule "synthesizability", but, so far, there is no consensus on whether or not a molecule is synthesizable. In this paper we introduce the Retro-Score (RScore), which computes a synthetic accessibility score of molecules by performing a full retrosynthetic analysis through our data-driven synthetic planning software Spaya, and its dedicated API: Spaya-API (https://spaya.ai). We start by comparing several synthetic accessibility scores to a binary "chemist score" as estimated by chemists on a bench of generated molecules, as a first experimental validation that the RScore is a reliable synthetic accessibility score. We then describe a pipeline to generate molecules that validate a list of targets while still being easy to synthesize. We further this idea by performing experiments comparing molecular generator outputs across a range of constraints and conditions. We show that the RScore can be learned by a Neural Network, which leads to a new score: RSPred. We demonstrate that using the RScore or RSPred as a constraint during molecular generation enables our molecular generators to produce more synthesizable solutions, with higher diversity. The open-source Python code containing all the scores and the experiments can be found on ( https://github.com/iktos/generation-under-synthetic-constraint ).

17.
J Chem Inf Model ; 63(13): 3983-3998, 2023 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-37347961

RESUMEN

Generative models are being increasingly used in drug discovery, very often coupled with absorption, distribution, metabolism, and excretion (ADME) bioassays or quantitative structure-activity relationship (QSAR) models to optimize a given set of properties. The molecules proposed by these algorithms are often revealed to be false positives; that is, they are predicted to be active and turn out to be inactive after synthesis and testing, mostly due to overoptimization of the predicted scores, which leads to an actual decrease or stagnation of the real scores. This behavior is also known as the "hacking" of the predictive models by the generative model during the optimization step. This issue is reminiscent of adversarial examples in machine learning and it can be seen as enunciated by Goodhart's law: "when a measure becomes a target, it ceases to be a good measure." This issue is even more apparent in a multiparameter optimization (MPO) case, where the models need to extrapolate outside the training set distribution because there are no known molecules satisfying all the objectives simultaneously in the initial training set. Experimental evaluation of this problem is a hard and expensive task since it requires synthesis and testing of the generated molecules. Thus, efforts have been made to develop in silico "oracles"─real-valued functions used as proxies for molecular properties─to help with the evaluation of these generative-model-based pipelines. However, these oracles have had a limited value so far because they are often too easy to model in comparison with biological assays and are usually limited to mono-objective cases. In this work, we introduce a simulator of multitarget assays using a smartly initialized neural network (NN) that returns continuous values for any input molecule. We use this oracle to replicate a real-world prospective lead optimization (LO) scenario. First, we trained predictive models on an initial small sample of molecules aimed at predicting their oracle values. Afterward, we generated new optimized molecules using the open-source GuacaMol package coupled with the previously built predictive models. Finally, we selected compounds matching the candidate drug target profile (CDTP) according to the predicted values and evaluated them by computing the true oracle values. We observed that even when the predictive models had excellent estimated performance metrics, the final selection still contained multiple false positives according to the NN-based oracle. Then, we evaluated the optimization behavior in mono- and bi-objective scenarios using either a logistic regression or a random forest predictive model. We also propose and evaluate several methods to help mitigate the hacking issue.


Asunto(s)
Algoritmos , Objetivos , Estudios Prospectivos , Redes Neurales de la Computación , Bioensayo
19.
Clin Breast Cancer ; 23(5): 527-537, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37183096

RESUMEN

PURPOSE: Breast cancer molecular subtypes show significant differences in different ethnic groups in the United States, but no study has evaluated genetic ancestry in breast cancer in Brazilian women. METHODS: Breast cancer patients from distinct parts of Brazil were evaluated. Molecular subtypes were determined by immunohistochemistry. Genetic ancestry was evaluated using a panel of 46 AIMs (ancestry informative markers), which classified genetic ancestry as European, African, Asian, and Amerindian. PCR products were subjected to capillary electrophoresis and analyzed using GeneMapper 4.0 software. Ancestry was evaluated with Structure v.2.3.3 software. Ancestry was tested for correlations with geographic region and molecular subtype. The chi-square test and ANOVA with Bonferroni adjustment were applied. RESULTS: Genetic ancestry and clinical data were evaluated in 1127 patients. Higher rates of self-reported white ethnicity, European ancestry, and HER-2- luminal tumors were identified in the South region, which may influence age at diagnosis and result in a higher rate of early tumors. Conversely, higher rates of African ancestry in the North and Northeast regions, self-reported nonwhite ethnicity, HER-2+ tumors, and triple-negative tumors were noted. Triple-negative and HER-2+ tumors were associated with higher advanced and metastatic disease rates at diagnosis, with triple-negative tumors being more frequent in young women. CONCLUSION: Differences in genetic ancestry, self-reported ethnicity, and molecular subtype were found between Brazilian demographic regions. Knowledge of these features may contribute to a better understanding of age at diagnosis and the molecular distribution of breast cancer in Brazil.


Asunto(s)
Neoplasias de la Mama , Femenino , Humanos , Población Negra , Brasil/epidemiología , Neoplasias de la Mama/etnología , Neoplasias de la Mama/genética , Etnicidad/genética , Autoinforme
20.
Pathobiology ; 90(5): 344-355, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37031678

RESUMEN

INTRODUCTION: TP53 is the most frequently mutated gene in lung tumors, but its prognostic role in admixed populations, such as Brazilians, remains unclear. In this study, we aimed to evaluate the frequency and clinicopathological impact of TP53 mutations in non-small cell lung cancer (NSCLC) patients in Brazil. METHODS: We analyzed 446 NSCLC patients from Barretos Cancer Hospital. TP53 mutational status was evaluated through targeted next-generation sequencing (NGS) and the variants were biologically classified as disruptive/nondisruptive and as truncating/nontruncating. We also assessed genetic ancestry using 46 ancestry-informative markers. Analysis of lung adenocarcinomas from the cBioportal dataset was performed. We further examined associations of TP53 mutations with patients' clinicopathological features. RESULTS: TP53 mutations were detected in 64.3% (n = 287/446) of NSCLC cases, with a prevalence of 60.4% (n = 221/366) in lung adenocarcinomas. TP53 mutations were associated with brain metastasis at diagnosis, tobacco consumption, and higher African ancestry. Disruptive and truncating mutations were associated with a younger age at diagnosis. Additionally, cBioportal dataset revealed that TP53 mutations were associated with younger age and Black skin color. Patients harboring disruptive/truncating TP53 mutations had worse overall survival than nondisruptive/nontruncating and wild-type patients. CONCLUSION: TP53 mutations are common in Brazilian lung adenocarcinomas, and their biological characterization as disruptive and truncating mutations is associated with African ancestry and shorter overall survival.


Asunto(s)
Adenocarcinoma del Pulmón , Población Negra , Neoplasias Pulmonares , Proteína p53 Supresora de Tumor , Humanos , Adenocarcinoma del Pulmón/etnología , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/mortalidad , Adenocarcinoma del Pulmón/patología , Población Negra/genética , Brasil/epidemiología , Carcinoma de Pulmón de Células no Pequeñas/etnología , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/etnología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Mutación , Prevalencia , Pronóstico , Proteína p53 Supresora de Tumor/genética
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