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1.
Biomed Res Int ; 2024: 3716786, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39130533

RESUMO

Background: Dengue fever (DF) is a mosquito-borne illness with substantial economic and societal impact. Understanding laboratory trends of hospitalized Dominican Republic (DR) pediatric patients could help develop screening procedures in low-resourced settings. We sought to describe laboratory findings over time in DR children with DF and DF severity from 2018 to 2020. Methods: Clinical information was obtained prospectively from recruited children with DF. Complete blood count (CBC) laboratory measures were assessed across Days 1-10 of fever. Participants were classified as DF-negative and DF-positive and grouped by severity. We assessed associations of DF severity with demographics, clinical characteristics, and peripheral blood studies. Using linear mixed-models, we assessed if hematologic values/trajectories differed by DF status/severity. Results: A total of 597 of 1101 with a DF clinical diagnosis were serologically evaluated, and 574 (471 DF-positive) met inclusion criteria. In DF, platelet count and hemoglobin were higher on earlier days of fever (p < = 0.0017). Eighty had severe DF. Severe DF risk was associated with thrombocytopenia, intraillness anemia, and leukocytosis, differing by fever day (p < = 0.001). Conclusions: In a pediatric hospitalized DR cohort, we found marked anemia in late stages of severe DF, unlike the typically seen hemoconcentration. These findings, paired with clinical symptom changes over time, may help guide risk-stratified screenings for resource-limited settings.


Assuntos
Vírus da Dengue , Dengue , Humanos , República Dominicana/epidemiologia , Dengue/epidemiologia , Dengue/sangue , Dengue/virologia , Dengue/diagnóstico , Masculino , Feminino , Pré-Escolar , Contagem de Células Sanguíneas , Lactente , Vírus da Dengue/isolamento & purificação , Criança , Epidemias , Anemia/epidemiologia , Anemia/sangue , Trombocitopenia/epidemiologia , Trombocitopenia/sangue , Trombocitopenia/virologia , Estudos Prospectivos
2.
Front Digit Health ; 6: 1344103, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38895515

RESUMO

Objective: To introduce MexOMICS, a Mexican Consortium focused on establishing electronic databases to collect, cross-reference, and share health-related and omics data on the Mexican population. Methods: Since 2019, the MexOMICS Consortium has established three electronic-based registries: the Mexican Twin Registry (TwinsMX), Mexican Lupus Registry (LupusRGMX), and the Mexican Parkinson's Research Network (MEX-PD), designed and implemented using the Research Electronic Data Capture web-based application. Participants were enrolled through voluntary participation and on-site engagement with medical specialists. We also acquired DNA samples and Magnetic Resonance Imaging scans in subsets of participants. Results: The registries have successfully enrolled a large number of participants from a variety of regions within Mexico: TwinsMX (n = 2,915), LupusRGMX (n = 1,761) and MEX-PD (n = 750). In addition to sociodemographic, psychosocial, and clinical data, MexOMICS has collected DNA samples to study the genetic biomarkers across the three registries. Cognitive function has been assessed with the Montreal Cognitive Assessment in a subset of 376 MEX-PD participants. Furthermore, a subset of 267 twins have participated in cognitive evaluations with the Creyos platform and in MRI sessions acquiring structural, functional, and spectroscopy brain imaging; comparable evaluations are planned for LupusRGMX and MEX-PD. Conclusions: The MexOMICS registries offer a valuable repository of information concerning the potential interplay of genetic and environmental factors in health conditions among the Mexican population.

3.
Twin Res Hum Genet ; 27(2): 85-96, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38699821

RESUMO

TwinsMX registry is a national research initiative in Mexico that aims to understand the complex interplay between genetics and environment in shaping physical and mental health traits among the country's population. With a multidisciplinary approach, TwinsMX aims to advance our knowledge of the genetic and environmental mechanisms underlying ethnic variations in complex traits and diseases, including behavioral, psychometric, anthropometric, metabolic, cardiovascular and mental disorders. With information gathered from over 2800 twins, this article updates the prevalence of several complex traits; and describes the advances and novel ideas we have implemented such as magnetic resonance imaging. The future expansion of the TwinsMX registry will enhance our comprehension of the intricate interplay between genetics and environment in shaping health and disease in the Mexican population. Overall, this report describes the progress in the building of a solid database that will allow the study of complex traits in the Mexican population, valuable not only for our consortium, but also for the worldwide scientific community, by providing new insights of understudied genetically admixed populations.


Assuntos
Interação Gene-Ambiente , Sistema de Registros , Humanos , México/epidemiologia , Masculino , Feminino , Adulto , Doenças em Gêmeos/genética , Doenças em Gêmeos/epidemiologia , Pessoa de Meia-Idade , Gêmeos Monozigóticos/genética , Gêmeos Dizigóticos/genética , Transtornos Mentais/genética , Transtornos Mentais/epidemiologia , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/epidemiologia
4.
Microbiol Spectr ; 12(6): e0005724, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38682931

RESUMO

Streptococcus agalactiae [group B Streptococcus (GBS)] poses a major threat as the primary cause of early-onset neonatal invasive disease, particularly when mothers are colonized rectovaginally. Although culture remains the gold standard for antepartum GBS screening, quantitative polymerase chain reaction (qPCR) offers advantages in terms of sensitivity and turnaround time. The aim of this study was to validate the clinical utility of an automated qPCR laboratory-developed test (LDT) for antepartum GBS screening using the Panther Fusion Open Access system (Hologic, California, USA). The LDT targeted a conserved region of the GBS surface immunogenic protein gene, demonstrating no cross-reactivity and high coverage (99.82%-99.99%). The limit of detection (LoD) was 118 CFU/mL. Comparison with commercial qPCR assays (Panther Fusion GBS and VIASURE Streptococcus B Real-Time) revealed an overall agreement of 99.7%, with a robust Cohen's kappa coefficient of 0.992. Testing of 285 rectovaginal swabs from pregnant women and 15 external quality assessment samples demonstrated exceptional diagnostic performance of the LDT, achieving a diagnostic sensitivity and specificity of 100%, underscoring its accuracy. Prevalence and predictive values were also determined to reinforce test reliability. Our research highlights the limitations of culture-based screening and supports the suitability of our qPCR-based LDT for GBS detection in a clinical setting.IMPORTANCERectovaginal colonization by GBS is a major risk factor for early-onset invasive neonatal disease. The most effective approach to reducing the incidence of early-onset disease (EOD) has been described as universal screening, involving assessment of GBS colonization status in late pregnancy and intrapartum antibiotic prophylaxis. Despite its turnaround time and sensitivity limitations, culture remains the gold standard method for GBS screening. However, nucleic acid amplification-based tests, such as qPCR, have been utilized due to their speed and high sensitivity and specificity. This study validated the clinical usefulness of an automated qPCR-LDT for antepartum GBS screening through the Panther Fusion Open Access system (Hologic). Our study addresses the critical need for more robust, sensitive, and rapid strategies for GBS screening in pregnant women that could favorably impact the incidence of EOD.


Assuntos
Complicações Infecciosas na Gravidez , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade , Infecções Estreptocócicas , Streptococcus agalactiae , Streptococcus agalactiae/genética , Streptococcus agalactiae/isolamento & purificação , Humanos , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/microbiologia , Feminino , Gravidez , Reação em Cadeia da Polimerase em Tempo Real/métodos , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/microbiologia , Vagina/microbiologia , Limite de Detecção , Adulto
5.
J Psychiatr Res ; 171: 346-353, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38354668

RESUMO

Several studies have examined the association of externalizing polygenic scores (PGS) with externalizing symptoms in samples of European ancestry. However, less is known about the associations of externalizing polygenic vulnerability in relation to phenotypic externalizing disorders among individuals of different ancestries, such as Mexican youth. Here, we leveraged the largest genome-wide association study on externalizing behaviors that included over 1 million individuals of European ancestry to examine associations of externalizing PGS with a range of externalizing disorders in Mexican adolescents, and investigated whether adversity exposure in childhood moderated these associations. Participants (N = 1064; age range 12-17 years old; 58.8% female) were adolescents recruited for a general population survey on adolescent mental health in the Mexico City Metropolitan region and were genotyped. Childhood adversity exposure and externalizing disorders, specifically attention-deficit hyperactivity disorder (ADHD), conduct disorder, oppositional defiant disorder, and substance use disorder, were assessed via the computer-assisted World Mental Health Composite International Diagnostic Interview for adolescents. A greater externalizing PGS was associated with a greater odds of any externalizing disorder (OR = 1.29 [1.12, 1.48]; p < 0.01) and ADHD (OR = 1.40 [1.15, 1.70]; p < 0.01) in the whole sample, and in females in particular. There were no main effects of the externalizing PGS on conduct disorder, oppositional defiant disorder, or substance use disorder, nor did adversity exposure moderate these associations. Our results suggest that greater genetic propensity for externalizing disorders is associated with increased odds of any externalizing disorders and ADHD among Mexican adolescents, furthering our understanding of externalizing disorder manifestation in this population.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno da Conduta , Transtornos Relacionados ao Uso de Substâncias , Humanos , Adolescente , Feminino , Criança , Masculino , Estudo de Associação Genômica Ampla , México , Transtorno da Conduta/epidemiologia , Transtorno da Conduta/genética , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/genética , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/genética , Transtornos Relacionados ao Uso de Substâncias/complicações
6.
Twin Res Hum Genet ; : 1-9, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37842863

RESUMO

Astigmatism and myopia are two common ocular refractive errors that can impact daily life, including learning and productivity. Current knowledge suggests that the etiology of these conditions is the result of a complex interplay between genetic and environmental factors. Studies in populations of European ancestry have demonstrated a higher concordance of refractive errors in monozygotic (MZ) twins compared to dizygotic (DZ) twins. However, there is a lack of studies on genetically informative samples of multi-ethnic ancestry. This study aimed to estimate the genetic contribution to astigmatism and myopia in the Mexican population. A sample of 1399 families, including 243 twin pairs and 1156 single twins, completed a medical questionnaire about their own and their co-twin's diagnosis of astigmatism and myopia. Concordance rates for astigmatism and myopia were estimated, and heritability and genetic correlations were determined using a bivariate ACE Cholesky decomposition method, decomposed into A (additive genetic), C (shared environmental) and E (unique environmental) components. The results showed a higher concordance rate for astigmatism and myopia for MZ twins (.74 and .74, respectively) than for DZ twins (.50 and .55). The AE model, instead of the ACE model, best fitted the data. Based on this, heritability estimates were .81 for astigmatism and .81 for myopia, with a cross-trait genetic correlation of rA = .80, nonshared environmental correlation rE = .89, and a phenotypic correlation of rP = .80. These results are consistent with previous findings in other populations, providing evidence for a similar genetic architecture of these conditions in the multi-ethnic Mexican population.

7.
Transl Psychiatry ; 13(1): 134, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37185805

RESUMO

Obsessive-compulsive disorder (OCD) affects 2-3% of the population. One-third of patients are poorly responsive to conventional therapies, and for a subgroup, gamma knife capsulotomy (GKC) is an option. We examined lesion characteristics in patients previously treated with GKC through well-established programs in Providence, RI (Butler Hospital/Rhode Island Hospital/Alpert Medical School of Brown University) and São Paulo, Brazil (University of São Paolo). Lesions were traced on T1 images from 26 patients who had received GKC targeting the ventral half of the anterior limb of the internal capsule (ALIC), and the masks were transformed into MNI space. Voxel-wise lesion-symptom mapping was performed to assess the influence of lesion location on Y-BOCS ratings. General linear models were built to compare the relationship between lesion size/location along different axes of the ALIC and above or below-average change in Y-BOCS ratings. Sixty-nine percent of this sample were full responders (≥35% improvement in OCD). Lesion occurrence anywhere within the targeted region was associated with clinical improvement, but modeling results demonstrated that lesions occurring posteriorly (closer to the anterior commissure) and dorsally (closer to the mid-ALIC) were associated with the greatest Y-BOCS reduction. No association was found between Y-BOCS reduction and overall lesion volume. GKC remains an effective treatment for refractory OCD. Our data suggest that continuing to target the bottom half of the ALIC in the coronal plane is likely to provide the dorsal-ventral height required to achieve optimal outcomes, as it will cover the white matter pathways relevant to change. Further analysis of individual variability will be essential for improving targeting and clinical outcomes, and potentially further reducing the lesion size necessary for beneficial outcomes.


Assuntos
Transtorno Obsessivo-Compulsivo , Radiocirurgia , Humanos , Brasil , Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/cirurgia , Radiocirurgia/métodos , Resultado do Tratamento , Cápsula Interna/diagnóstico por imagem , Cápsula Interna/cirurgia
8.
Mar Drugs ; 21(2)2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36827134

RESUMO

Due to the constant growth of the human population and anthropological activity, it has become necessary to use sustainable and affordable technologies that satisfy the current and future demand for agricultural products. Since the nutrients available to plants in the soil are limited and the need to increase the yields of the crops is desirable, the use of chemical (inorganic or NPK) fertilizers has been widespread over the last decades, causing a nutrient shortage due to their misuse and exploitation, and because of the uncontrolled use of these products, there has been a latent environmental and health problem globally. For this reason, green biotechnology based on the use of microalgae biomass is proposed as a sustainable alternative for development and use as soil improvers for crop cultivation and phytoremediation. This review explores the long-term risks of using chemical fertilizers for both human health (cancer and hypoxia) and the environment (eutrophication and erosion), as well as the potential of microalgae biomass to substitute current fertilizer using different treatments on the biomass and their application methods for the implementation on the soil; additionally, the biomass can be a source of carbon mitigation and wastewater treatment in agro-industrial processes.


Assuntos
Microalgas , Solo , Humanos , Fertilizantes/análise , Pegada de Carbono , Carbono , Biotecnologia , Biomassa
9.
Interv Neuroradiol ; : 15910199231153195, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36751025

RESUMO

BACKGROUND AND AIMS: Endovascular treatment for cerebrovascular disease is accepted as a first-line option with level I evidence in patients with an early and late time of window of onset symptoms, and an additional option in patients who do not respond or with contraindications to systemic thrombolysis; nevertheless the efficacy and outcomes of some groups were not clear, one of them are patients aged 80 years and older, because they were excluded of the trials, so the evidence is controversial with significant heterogeneity, for that reason in our study, we decided to analyze the age in the patients treated in our stroke center, as a predictor of prognosis, and to provide a baseline for the establishment of personalized treatment plans. METHODS: Observational, retrospective study of patients that received endovascular treatment for cerebrovascular disease in a Colombian stroke center between 2016 and 2020, continuous and categorical variables were compared using the Student's t test and Chi-Square. To determine cut-off points in the variable against death and Rankin score variable on 90th day. RESULTS: In total, 108 patients were recruited, 35 of them were of 80 or more years, and the mean age was 72.7 years, we found age as a significant variable to predict the risk in the population over 80 years of age [RR 3.37 CI (95% 1.14-103) p = 0.029]. CONCLUSIONS: Age younger than 80 is a significant predictor for results and long-term outcomes in patients suffering from stroke, and in patients older than 80 years old a Thrombolysis in Cerebral Infarction score 2b-3 is a predictor of good outcomes. Further studies are needed to evaluate the relationship between intrahospital complications and long-term outcomes.

10.
J Pediatric Infect Dis Soc ; 12(3): 169-172, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-36537278

RESUMO

We performed an observational cohort study to assess associations between genetic factors of dengue fever (DF) severity in children in the Dominican Republic. A total of 488 participants had serologically confirmed DF. We replicated the association between the IFIH1 gene (rs1990760) and severe DF (n = 80/488, p = 0.006) and identified novel associations needing further investigation.


Assuntos
Dengue , Dengue Grave , Humanos , Criança , Dengue/diagnóstico , Dengue/epidemiologia , República Dominicana/epidemiologia , Estudos de Coortes , Genômica
11.
J Cardiovasc Dev Dis ; 9(12)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36547437

RESUMO

BACKGROUND: Predicting beat-to-beat blood pressure has several clinical applications. While most machine learning models focus on accuracy, it is necessary to build models that explain the relationships of hemodynamical parameters with blood pressure without sacrificing accuracy, especially during exercise. OBJECTIVE: The aim of this study is to use the RuleFit model to measure the importance, interactions, and relationships among several parameters extracted from photoplethysmography (PPG) and electrocardiography (ECG) signals during a dynamic weight-bearing test (WBT) and to assess the accuracy and interpretability of the model results. METHODS: RuleFit was applied to hemodynamical ECG and PPG parameters during rest and WBT in six healthy young subjects. The WBT involves holding a 500 g weight in the left hand for 2 min. Blood pressure is taken in the opposite arm before and during exercise thereof. RESULTS: The root mean square error of the model residuals was 4.72 and 2.68 mmHg for systolic blood pressure and diastolic blood pressure, respectively, during rest and 4.59 and 4.01 mmHg, respectively, during the WBT. Furthermore, the blood pressure measurements appeared to be nonlinear, and interaction effects were observed. Moreover, blood pressure predictions based on PPG parameters showed a strong correlation with individual characteristics and responses to exercise. CONCLUSION: The RuleFit model is an excellent tool to study interactions among variables for predicting blood pressure. Compared to other models, the RuleFit model showed superior performance. RuleFit can be used for predicting and interpreting relationships among predictors extracted from PPG and ECG signals.

12.
Heliyon ; 8(11): e11238, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36387577

RESUMO

Wildfires in the urban-forest interface constitute a civil protection emergency, causing considerable personal injury and damage to properties. The potential impacts of wildfires on buildings can be minimized by reducing the surrounding fuel and the use of structural materials with low flammability. However, the costs associated with implementing these actions and the responsibility for maintenance usually present conflicts with the property owners. This study aimed to identify minimum safety distances in wildland-urban interfaces within priority areas. The priority areas were identified based on the integration of fire risk and fuel hazard. Radiant heat is a variable in the behavior of fire that directly influences the definition of safety distances. In this research the radiant heat transfer was calculated based on the potential fire behavior for each study area. A comparative study of the horizontal heat transfer method and the radiant heat flux model was carried out. The horizontal heat transfer method indicated the highest vegetation-free distances, ranging from 23 m to 32 m. Some safety distances were validated using experimental fires and wildfires. The findings from the experimental fires and wildfires emphasize the need for a progressive fuel load reduction to mitigate radiant heat transfer. This may include both the removal of surface fuel and removal of trees to mitigate against crown fires. Our findings provide relevant information for decision-making on the effectiveness and efficiency of safety distances at the wildland-urban interface.

13.
Molecules ; 27(18)2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36144740

RESUMO

The photolyase family consists of flavoproteins with enzyme activity able to repair ultraviolet light radiation damage by photoreactivation. DNA damage by the formation of a cyclobutane pyrimidine dimer (CPD) and a pyrimidine-pyrimidone (6-4) photoproduct can lead to multiple affections such as cellular apoptosis and mutagenesis that can evolve into skin cancer. The development of integrated applications to prevent the negative effects of prolonged sunlight exposure, usually during outdoor activities, is imperative. This study presents the functions, characteristics, and types of photolyases, their therapeutic and cosmetic applications, and additionally explores some photolyase-producing microorganisms and drug delivery systems.


Assuntos
Desoxirribodipirimidina Fotoliase , Reparo do DNA , Desoxirribodipirimidina Fotoliase/genética , Desoxirribodipirimidina Fotoliase/metabolismo , Flavoproteínas , Dímeros de Pirimidina , Pirimidinas , Pirimidinonas , Raios Ultravioleta/efeitos adversos
14.
Rev. colomb. cardiol ; 29(5): 551-558, jul.-set. 2022. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1423781

RESUMO

Resumen Introducción: la fibrilación auricular no valvular es la arritmia cardiaca más frecuente en las personas mayores que se ha relacionado con diferentes desenlaces adversos, como el ataque cerebrovascular, el cual en el 80% de los casos se puede prevenir con anticoagulantes orales, beneficio que está condicionado por una adecuada adherencia terapéutica. Objetivo: determinar la adherencia al tratamiento anticoagulante en pacientes mayores de 65 años con fibrilación auricular no valvular y factores asociados. Método: estudio observacional analítico de corte transversal, realizado en la clínica de anticoagulación de la Fundación Oftalmológica de Santander, en el que se evaluó la adherencia terapéutica por la escala de Morisky 8 en 102 pacientes, con un promedio de edad de 76 años. Se analizaron variables sociodemográficas, clínicas, síndromes geriátricos y relacionadas con el sistema de salud, luego se realizó un análisis bivariado. Se aceptó como significancia estadística un valor de p < 0.05. Resultados: se encontró adherencia farmacológica baja en el 42,1%; el olvido en la toma de su medicamento (50%) fue el factor más frecuente. Aspectos relacionados con el sistema de salud, como la inconformidad con el despacho del medicamento anticoagulante (OR: 2,97; IC 95%: 1.1-8.2; p = 0,02) y el despacho inoportuno (OR: 5.85; IC 95%: 1.5-32.8; p = 0,005) fueron variables asociadas a baja adherencia terapéutica. La toma de antiagregantes plaquetarios (p = 0,04) y la polifarmacia (p = 0,04) se asociaron con adherencia farmacológica moderada y alta. Conclusiones: la prevalencia de baja adherencia al tratamiento farmacológico es significativa. Es necesario conocer algunos aspectos del sistema de salud que limitan la adherencia dado que impactan en la efectividad de los anticoagulantes orales en población mayor.


Abstract Introduction: non-valvular atrial fibrillation is the most common cardiac arrhythmia in the elderly and has been related to different adverse outcomes such as stroke, which in 80% of cases can be prevented with oral anticoagulants, a benefit that is conditioned by an adequate therapeutic adherence. Objective: to determine adherence to anticoagulant treatment in patients older than 65 years with non-valvular atrial fibrillation and associated factors. Methodology: cross-sectional analytical observational study conducted at the FOSCAL anticoagulation clinic. Therapeutic adherence was evaluated using the Morisky 8 scale in 102 patients, with an average age of 76 years. Sociodemographic, clinical, geriatric syndrome and health system-related variables were analyzed, then a bivariate analysis was performed. A value of p < 0.05 was accepted as statistical significance. Results: Low pharmacological adherence was found in 42.1%, whose main cause was forgetting to take their medication (50%), likewise, the variables associated with the health system with low adherence were disagreement with the dispatch of the anticoagulant medication (OR: 2.97; 95% CI: 1.1-8.2; p = 0,02) and untimely dispatch (OR: 5.85; CI 95% 1.5-32.8; p = 0,005). Taking antiplatelet agents (p = 0.04) and the presence of polypharmacy (p = 0.04) were associated with moderate and high pharmacological adherence. Conclusions: the prevalence of low adherence to pharmacological treatment is significant. It is necessary to know some aspects of the health system that limit adherence since they impact the effectiveness of oral antiocogulants in the elderly population.

15.
Nanomaterials (Basel) ; 12(10)2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35630934

RESUMO

Resonant tunneling devices are still under study today due to their multiple applications in optoelectronics or logic circuits. In this work, we review an out-of-equilibrium GaAs/AlGaAs double-barrier resonant tunneling diode system, including the effect of donor density and external potentials in a self-consistent way. The calculation method uses the finite-element approach and the Landauer formalism. Quasi-stationary states, transmission probability, current density, cut-off frequency, and conductance are discussed considering variations in the donor density and the width of the central well. For all arrangements, the appearance of negative differential resistance (NDR) is evident, which is a fundamental characteristic of practical applications in devices. Finally, a comparison of the simulation with an experimental double-barrier system based on InGaAs with AlAs barriers reported in the literature has been obtained, evidencing the position and magnitude of the resonance peak in the current correctly.

16.
Front Microbiol ; 13: 845546, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35558106

RESUMO

The Orthomyxoviridae family includes the genera Influenzavirus, Isavirus, Quaranjavirus, and Thogotovirus. In turn, Influenzavirus can be classified into four types: α, ß, γ, and δ (Formerly A, B, C, and D), from which Alphainfluenzavirus (AIV) has the broadest host range, including birds, mammals, reptiles, and amphibians. Additionally, AIV has shown global epidemiological relevance owing to its pandemic potential. The epidemiological relevance of Chiropteran due to its multiple functional characteristics makes them ideal reservoirs for many viral agents. Recently, new influenza-like subtypes have been reported in Neotropical bats, but little is known about the relevance of bats as natural reservoirs of influenza viruses. Therefore, the current study aimed to determine the presence of AIV and new influenza-like subtypes in South American bats. For a better understanding of the drivers and interactions between AIV and bats, we used molecular assays with different gene targets (i.e., M, NP, and PB1) to identify AIV in New World bats. A housekeeping gene (CytB) PCR was used to check for nucleic acid preservation and to demonstrate the bat-origin of the samples. A total of 87 free-living bats belonging to 25 different species of the families Phyllostomidae and Vespertilionidae were collected in Casanare, Colombia. As a result, this study found seven AIV-positive bat species, three of them reported for the first time as AIV prone hosts. Neither of the AIV-like analyzed samples were positive for H17N10/H18/N11 subtypes. Although additional information is needed, the presence of a completely new or divergent AIV subtype in neotropical bats cannot be discarded. Collectively, the results presented here expand the epidemiological knowledge and distribution of AIV in neotropical free-ranging bats and emphasize the need to continue studying these viruses to establish the role they could play as a threat to animal and public health.

17.
Cell Mol Life Sci ; 79(5): 239, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35416520

RESUMO

Many people around the world suffer from some form of paralysis caused by spinal cord injury (SCI), which has an impact on quality and life expectancy. The spinal cord is part of the central nervous system (CNS), which in mammals is unable to regenerate, and to date, there is a lack of full functional recovery therapies for SCI. These injuries start with a rapid and mechanical insult, followed by a secondary phase leading progressively to greater damage. This secondary phase can be potentially modifiable through targeted therapies. The growing literature, derived from mammalian and regenerative model studies, supports a leading role for mitochondria in every cellular response after SCI: mitochondrial dysfunction is the common event of different triggers leading to cell death, cellular metabolism regulates the immune response, mitochondrial number and localization correlate with axon regenerative capacity, while mitochondrial abundance and substrate utilization regulate neural stem progenitor cells self-renewal and differentiation. Herein, we present a comprehensive review of the cellular responses during the secondary phase of SCI, the mitochondrial contribution to each of them, as well as evidence of mitochondrial involvement in spinal cord regeneration, suggesting that a more in-depth study of mitochondrial function and regulation is needed to identify potential targets for SCI therapeutic intervention.


Assuntos
Traumatismos da Medula Espinal , Regeneração da Medula Espinal , Animais , Sistema Nervoso Central/metabolismo , Humanos , Mamíferos , Mitocôndrias/metabolismo , Regeneração Nervosa , Recuperação de Função Fisiológica , Medula Espinal/metabolismo , Traumatismos da Medula Espinal/metabolismo , Regeneração da Medula Espinal/fisiologia
18.
Front Oncol ; 12: 835626, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35433488

RESUMO

Purposes: Most molecular-based published studies on breast cancer do not adequately represent the unique and diverse genetic admixture of the Latin American population. Searching for similarities and differences in molecular pathways associated with these tumors and evaluating its impact on prognosis may help to select better therapeutic approaches. Patients and Methods: We collected clinical, pathological, and transcriptomic data of a multi-country Latin American cohort of 1,071 stage II-III breast cancer patients of the Molecular Profile of Breast Cancer Study (MPBCS) cohort. The 5-year prognostic ability of intrinsic (transcriptomic-based) PAM50 and immunohistochemical classifications, both at the cancer-specific (OSC) and disease-free survival (DFS) stages, was compared. Pathway analyses (GSEA, GSVA and MetaCore) were performed to explore differences among intrinsic subtypes. Results: PAM50 classification of the MPBCS cohort defined 42·6% of tumors as LumA, 21·3% as LumB, 13·3% as HER2E and 16·6% as Basal. Both OSC and DFS for LumA tumors were significantly better than for other subtypes, while Basal tumors had the worst prognosis. While the prognostic power of traditional subtypes calculated with hormone receptors (HR), HER2 and Ki67 determinations showed an acceptable performance, PAM50-derived risk of recurrence best discriminated low, intermediate and high-risk groups. Transcriptomic pathway analysis showed high proliferation (i.e. cell cycle control and DNA damage repair) associated with LumB, HER2E and Basal tumors, and a strong dependency on the estrogen pathway for LumA. Terms related to both innate and adaptive immune responses were seen predominantly upregulated in Basal tumors, and, to a lesser extent, in HER2E, with respect to LumA and B tumors. Conclusions: This is the first study that assesses molecular features at the transcriptomic level in a multicountry Latin American breast cancer patient cohort. Hormone-related and proliferation pathways that predominate in PAM50 and other breast cancer molecular classifications are also the main tumor-driving mechanisms in this cohort and have prognostic power. The immune-related features seen in the most aggressive subtypes may pave the way for therapeutic approaches not yet disseminated in Latin America. Clinical Trial Registration: ClinicalTrials.gov (Identifier: NCT02326857).

19.
Carbohydr Polym ; 281: 119048, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35074120

RESUMO

This work focused on studying the effect of lamellae presence on the pasting profile of isolated avocado starch (C-type) obtained by a combined mechanical and ultrasonic process. Inductively Couple Plasma indicates that this starch is rich in P, K, Na, and Ca. This starch exhibits the most crystalline structure reported so far. The correlation between the morphological and structural properties throughout its pasting profile explains its apparent viscosity behavior. Granules exhibit a non-conventional irregular morphology with sizes ranging from 35 to 40 µm in their long side. DSC reveals endothermal transitions at 68 °C and 119 °C associated with the nanocrystals solvation and amylose-lipid complex, respectively. After gelatinization, the presence of lamellae originated from the partial fragmentation of the crystals. The pasting end exhibited a combined behavior between custard and hydrogel. This correlation could be considered a new methodology to understand the pasting behaviors in any starch.


Assuntos
Persea , Amido , Amilose/química , Amido/química , Temperatura , Viscosidade
20.
J Cancer Educ ; 37(5): 1433-1437, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-33954934

RESUMO

The importance of self-breast examination to identify early signs of breast cancer has been widely discussed in scientific literature. We conducted a cross-sectional survey of women aged 18 years and over (n = 547) living in urban and rural areas in the State of Jalisco, Mexico. Survey questions included measures on knowledge, attitudes, behaviors, and practices related to self-breast examination. We compared these measures between women living in urban and rural areas and women aged 18-39 years and 40+ years. Using t-test, we tested the significance of these differentials. Our results indicate that there is no significant difference in knowledge, attitudes, behavior, and practices regarding self-breast examination between women living in urban and in rural areas of Jalisco. However, we found some difference in these measures between women in 18-39 years and 40+ years. While the State of Jalisco has taken significant steps toward promoting significance of cancer prevention, further attention to women in the older cohort is recommended.


Assuntos
Neoplasias da Mama , Conhecimentos, Atitudes e Prática em Saúde , Adolescente , Adulto , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/prevenção & controle , Autoexame de Mama , Estudos Transversais , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Mamografia , México
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