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1.
bioRxiv ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38586020

RESUMO

Self-assembled materials capable of modulating their assembly properties in response to specific enzymes play a pivotal role in advancing 'intelligent' encapsulation platforms for biotechnological applications. Here, we introduce a previously unreported class of synthetic nanomaterials that programmatically interact with histone deacetylase (HDAC) as the triggering stimulus for disassembly. These nanomaterials consist of co-polypeptides comprising poly (acetyl L-lysine) and poly(ethylene glycol) blocks. Under neutral pH conditions, they self-assemble into particles. However, their stability is compromised upon exposure to HDACs, depending on enzyme concentration and exposure time. Our investigation, utilizing HDAC8 as the model enzyme, revealed that the primary mechanism behind disassembly involves a decrease in amphiphilicity within the block copolymer due to the deacetylation of lysine residues within the particles' hydrophobic domains. To elucidate the response mechanism, we encapsulated a fluorescent dye within these nanoparticles. Upon incubation with HDAC, the nanoparticle structure collapsed, leading to controlled release of the dye over time. Notably, this release was not triggered by denatured HDAC8, other proteolytic enzymes like trypsin, or the co-presence of HDAC8 and its inhibitor. We further demonstrated the biocompatibility and cellular effects of these materials and conducted a comprehensive computational study to unveil the possible interaction mechanism between enzymes and particles. By drawing parallels to the mechanism of naturally occurring histone proteins, this research represents a pioneering step toward developing functional materials capable of harnessing the activity of epigenetic enzymes such as HDACs.

2.
ACS Mater Au ; 4(2): 195-203, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38496050

RESUMO

Dielectric constant is an important property which is widely utilized in many scientific fields and characterizes the degree of polarization of substances under the external electric field. In this work, a structure-property relationship of the dielectric constants (ε) for a diverse set of polymers was investigated. A transparent mechanistic model was developed with the application of a machine learning approach that combines genetic algorithm and multiple linear regression analysis, to obtain a mechanistically explainable and transparent model. Based on the evaluation conducted using various validation criteria, four- and eight-variable models were proposed. The best model showed a high predictive performance for training and test sets, with R2 values of 0.905 and 0.812, respectively. Obtained statistical performance results and selected descriptors in the best models were analyzed and discussed. With the validation procedures applied, the models were proven to have a good predictive ability and robustness for further applications in polymer permittivity prediction.

3.
J Phys Chem B ; 128(9): 2190-2200, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38386478

RESUMO

The development of reusable polymeric materials inspires an attempt to combine renewable biomass with upcycling to form a biorenewable closed system. It has been reported that 2,5-furandicarboxylic acid (FDCA) can be recovered for recycling when incorporated as monomers into photodegradable polymeric systems. Here, we develop a procedure to better understand the photodegradation reactions combining density functional theory (DFT) based time-dependent excited-state molecular dynamics (TDESMD) studies with machine learning-based quantitative structure-activity relationships (QSAR) methodology. This procedure allows for the unveiling of hidden structural features between active orbitals that affect the rate of photodegradation and is coined InfoTDESMD. Findings show that electrotopological features are influential factors affecting the rate of photodegradation in differing environments. Additionally, statistical validations and knowledge-based analysis of descriptors are conducted to further understand the structural features' influence on the rate of photodegradation of polymeric materials.

4.
J Phys Chem Lett ; 15(2): 471-480, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38190332

RESUMO

Various coordination complexes have been the subject of experimental and theoretical studies in recent decades because of their fascinating photophysical properties. In this work, a combined experimental and computational approach was applied to investigate the optical properties of monocationic Ir(III) complexes. An interpretative machine learning-based quantitative structure-property relationship (ML/QSPR) model was successfully developed that could reliably predict the emission wavelength of the Ir(III) complexes and provide a foundation for the theoretical evaluation of the optical properties of Ir(III) complexes. A hypothesis was proposed to explain the differences in the emission wavelengths between structurally different individual Ir(III) complexes. The efficacy of the developed model was demonstrated by high R2 values of 0.84 and 0.87 for the training and test sets, respectively. It is worth noting that a relationship between the N-N distance in the diimine ligands of the Ir(III) complexes and emission wavelengths is detected. This effect is most probably associated with a degree of distortion in the octahedral geometry of the complexes, resulting in a perturbed ligand field. This combined experimental and computational approach shows great potential for the rational design of new Ir(III) complexes with the desired optical properties. Moreover, the developed methodology could be extended to other transition-metal complexes.

5.
Rev. argent. microbiol ; 55(4): 5-5, Dec. 2023.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1550712

RESUMO

Resumen El adenocarcinoma gástrico se asocia con la infección por Helicobacter pylori. La transición a un proceso de carcinogénesis está precedida por atrofia glandular, y los niveles séricos de pepsinógeno I y II (PGI y PGII) se correlacionan con este tipo de lesiones gástricas. El objetivo del trabajo fue estudiar posibles asociaciones de los niveles de pepsinógenos (PG) en suero en relación con la frecuencia de actividad serológica hacia antígenos de H. pylori. Se utilizaron muestras de suero de pacientes con patología gástrica asociada a H. pylori (n = 26) y de individuos asintomáticos como controles (n = 37). Los antígenos seroactivos se identificaron mediante inmunoblot utilizando un extracto proteico de H. pylori. Los títulos de anticuerpos anti-H. pylori y la concentración de PG en suero se determinaron por ELISA. De los 31 antígenos seroactivos identificados, 9 presentaron una frecuencia diferencial entre ambos grupos (116,7; 68,8; 61,9; 54,9; 45,6; 38,3; 36,5; 33,8 y 30,1 kDa) y solo 3 se relacionaron con niveles alterados de PG en suero. En el grupo control, la seropositividad del antígeno de 33,8 kDa se relacionó con un aumento de PGII, mientras que el antígeno de 68,8kDa se relacionó con valores normales de PG (PGII disminuido y PGI/PGII elevado), sugiriendo que la seropositividad a este antígeno podría ser un factor protector frente a patologías gástricas. La seropositividad del antígeno de 54,9 kDa se relacionó con valores alterados de PG indicadores de inflamación y atrofia gástrica (aumento de PGII y disminución de PGI/PGII). La identificación de alteraciones séricas en los niveles de pepsinógeno relacionadas con la seropositividad a los antígenos de 33,8; 54,9 y 68,8 kDa de H. pylori sienta un precedente para futuros estudios como posibles biomarcadores serológicos pronósticos.

6.
Immun Inflamm Dis ; 11(10): e1054, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37904687

RESUMO

INTRODUCTION: Waning immunity after vaccination justifies the need for additional effective COVID-19 treatments. Immunomodulation of local immune response at the oropharyngeal mucosa could hypothetically activate mucosal immunity, which can prevent SARS-CoV-2 main immune evasion mechanisms in early stages of the disease and send an effective warning to other components of immune system. Olive polyphenols are biologically active compounds with immunomodulatory activity. There are previous studies based on immunomodulation with olive polyphenols and respiratory infections using an enteral route, which point to potential effects on time to resolution of symptoms. The investigators sought to determine whether participants following immunomodulation with tiny quantities of high polyphenolic olive oil administered through an oromucosal route could have a better outcome in COVID-19. SUMMARY: This pilot clinical trial investigated the effect of buccopharyngeal administered high polyphenolic olive oil on COVID-19 incidence, duration, and severity. IMPORTANCE: Waning immunity after vaccination justifies the need of further research for additional effective treatments for COVID-19. OBJECTIVE: Immunomodulation of local immune response at the buccopharyngeal mucosa could hypothetically activate mucosal immunity, which would in turn difficult SARS-CoV-2 immune evasion mechanisms in early stages of the disease and send an effective warning to other components of immune system. Olive polyphenols are biologically active compounds with immunomodulatory activity. There are previous studies based on immunomodulation with olive polyphenols and respiratory infections, using an enteral route, which suggest potential shortening of time to resolution of symptoms. The investigators sought to determine whether participants following immunomodulation with tiny quantities of high polyphenolic olive oil administered through an oromucosal route could have a better outcome in COVID-19. DESIGN, SETTING, AND PARTICIPANTS: Double blind, randomized pilot clinical trial conducted at a single site, Talavera de la Reina, Spain. Potential study participants were identified by simple random sampling from the epidemiological database of contact patients recently diagnosed of COVID-19 during the study period. A total of 88 adult participants were enrolled and 84 completed the 3-month study, conducted between July 1, 2021 and August 31, 2022. INTERVENTION: Participants were randomized to receive oromucosal administered high polyphenolic olive oil, 2 mL twice a day for 3 months or no treatment. MAIN OUTCOME AND MEASURES: Primary outcomes were incidence, duration, and severity of COVID-19 after intervention. RESULTS: There were no differences in incidence between both groups but there were significant differences in duration, the median time to resolution of symptoms was 3 days in the high polyphenolic olive oil group compared with 7 days in the no-treatment group. Although time to resolution is directly related to severity, this study did not find any differences in severity. CONCLUSION AND RELEVANCE: Among full-vaccinated adults recent infected with COVID-19, a daily intake of tiny quantities of oromucosal administered high polyphenolic olive oil before infection significantly improved the time to symptom resolution. This finding strongly support the appropriateness of further deep research on the use of oromucosal administered high polyphenolic olive oil as an effective immune strategy against COVID-19.


Assuntos
COVID-19 , Adulto , Humanos , SARS-CoV-2 , Azeite de Oliva , Resultado do Tratamento , Fatores de Tempo
7.
Toxics ; 11(7)2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37505560

RESUMO

Industrial wastewater often consists of toxic chemicals and pollutants, which are extremely harmful to the environment. Heavy metals are toxic chemicals and considered one of the major hazards to the aquatic ecosystem. Analytical techniques, such as potentiometric methods, are some of the methods to detect heavy metals in wastewaters. In this work, the quantitative structure-property relationship (QSPR) was applied using a range of machine learning techniques to predict the stability constant (logßML) and potentiometric sensitivity (PSML) of 200 ligands in complexes with the heavy metal ions Cu2+, Cd2+, and Pb2+. In result, the logßML models developed for four ions showed good performance with square correlation coefficients (R2) ranging from 0.80 to 1.00 for the training and 0.72 to 0.85 for the test sets. Likewise, the PSML displayed acceptable performance with an R2 of 0.87 to 1.00 for the training and 0.73 to 0.95 for the test sets. By screening a virtual database of coumarin-like structures, several new ligands bearing the coumarin moiety were identified. Three of them, namely NEW02, NEW03, and NEW07, showed very good sensitivity and stability in the metal complexes. Subsequent quantum-chemical calculations, as well as physicochemical/toxicological profiling were performed to investigate their metal-binding ability and developability of the designed sensors. Finally, synthesis schemes are proposed to obtain these three ligands with major efficiency from simple resources. The three coumarins designed clearly demonstrated capability to be suitable as good florescent chemosensors towards heavy metals. Overall, the computational methods applied in this study showed a very good performance as useful tools for designing novel fluorescent probes and assessing their sensing abilities.

8.
Rev Argent Microbiol ; 55(4): 355-365, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37385833

RESUMO

Gastric adenocarcinoma is associated with Helicobacter pylori infection. The transition to a carcinogenic process is preceded by glandular atrophy and serum levels of pepsinogen I and II (PGI and PGII) correlate with this type of gastric lesions. Possible associations of serum PG levels in relation to the frequency of serological activity against H. pylori antigens were studied. Serum samples from patients with gastric pathology associated with H. pylori (n=26) and asymptomatic individuals as controls (n=37) were used. Seroactive antigens were identified by immunoblot using a protein extract of H. pylori. The antibody titers anti-H. pylori and the concentration of PGs in serum was determined by ELISA. Thirty-one seroactive antigens were identified, nine of which exhibited a differential frequency between both groups (116.7, 68.8, 61.9, 54.9, 45.6, 38.3, 36.5, 33.8 and 30.1kDa) and only 3 were related to altered levels of PGs in serum. In the control group, the seropositivity of the 33.8kDa antigen was related to an increase in PGII, while the 68.8kDa antigen was related to normal PG values (decreased PGII and elevated PGI/PGII levels) indicating that seropositivity to this antigen could be a protective factor to gastric pathology. The seropositivity of the 54.9kDa antigen was related to altered values of PGs indicative of inflammation and gastric atrophy (increased in PGII and decreased in PGI/PGII). The identification of serum alterations in pepsinogen levels related to seropositivity to H. pylori 33.8, 54.9 and 68.8kDa antigens sets a precedent for further study as possible prognostic serological biomarkers.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos , Pepsinogênio A , Infecções por Helicobacter/complicações , Estômago , Pepsinogênio C , Atrofia/complicações
9.
Molecules ; 28(8)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37110831

RESUMO

Multi-target drug development has become an attractive strategy in the discovery of drugs to treat of Alzheimer's disease (AzD). In this study, for the first time, a rule-based machine learning (ML) approach with classification trees (CT) was applied for the rational design of novel dual-target acetylcholinesterase (AChE) and ß-site amyloid-protein precursor cleaving enzyme 1 (BACE1) inhibitors. Updated data from 3524 compounds with AChE and BACE1 measurements were curated from the ChEMBL database. The best global accuracies of training/external validation for AChE and BACE1 were 0.85/0.80 and 0.83/0.81, respectively. The rules were then applied to screen dual inhibitors from the original databases. Based on the best rules obtained from each classification tree, a set of potential AChE and BACE1 inhibitors were identified, and active fragments were extracted using Murcko-type decomposition analysis. More than 250 novel inhibitors were designed in silico based on active fragments and predicted AChE and BACE1 inhibitory activity using consensus QSAR models and docking validations. The rule-based and ML approach applied in this study may be useful for the in silico design and screening of new AChE and BACE1 dual inhibitors against AzD.


Assuntos
Acetilcolinesterase , Doença de Alzheimer , Humanos , Acetilcolinesterase/uso terapêutico , Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/uso terapêutico , Inibidores da Colinesterase/química , Simulação de Acoplamento Molecular , Secretases da Proteína Precursora do Amiloide , Ácido Aspártico Endopeptidases , Precursor de Proteína beta-Amiloide
10.
Mol Divers ; 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37017875

RESUMO

Ubiquitin-proteasome system (UPS) is a highly regulated mechanism of intracellular protein degradation and turnover. The UPS is involved in different biological activities, such as the regulation of gene transcription and cell cycle. Several researchers have applied cheminformatics and artificial intelligence methods to study the inhibition of proteasomes, including the prediction of UPP inhibitors. Following this idea, we applied a new tool for obtaining molecular descriptors (MDs) for modeling proteasome Inhibition in terms of EC50 (µmol/L), in which a set of new MDs called atomic weighted vectors (AWV) and several prediction algorithms were used in cheminformatics studies. In the manuscript, a set of descriptors based on AWV are presented as datasets for training different machine learning techniques, such as linear regression, multiple linear regression (MLR), random forest (RF), K-nearest neighbors (IBK), multi-layer perceptron, best-first search, and genetic algorithm. The results suggest that these atomic descriptors allow adequate modeling of proteasome inhibitors despite artificial intelligence techniques, as a variant to build efficient models for the prediction of inhibitory activity.

11.
iScience ; 26(2): 105946, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36818294

RESUMO

Snakebite affects more than 1.8 million people annually. Factors explaining snakebite variability include farmers' behaviors, snake ecology and climate. One unstudied issue is how farmers' adaptation to novel climates affect their health. Here we examined potential impacts of adaptation on snakebite using individual-based simulations, focusing on strategies meant to counteract major crop yield decline because of changing rainfall in Sri Lanka. For rubber cropping, adaptation led to a 33% increase in snakebite incidence per farmer work hour because of work during risky months, but a 17% decrease in total annual snakebites because of decreased labor in plantations overall. Rice farming adaptation decreased snakebites by 16%, because of shifting labor towards safer months, whereas tea adaptation led to a general increase. These results indicate that adaptation could have both a positive and negative effect, potentially intensified by ENSO. Our research highlights the need for assessing adaptation strategies for potential health maladaptations.

12.
Toxics ; 10(12)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36548579

RESUMO

In this work, a dataset of more than 200 nitroaromatic compounds is used to develop Quantitative Structure-Activity Relationship (QSAR) models for the estimation of in vivo toxicity based on 50% lethal dose to rats (LD50). An initial set of 4885 molecular descriptors was generated and applied to build Support Vector Regression (SVR) models. The best two SVR models, SVR_A and SVR_B, were selected to build an Ensemble Model by means of Multiple Linear Regression (MLR). The obtained Ensemble Model showed improved performance over the base SVR models in the training set (R2 = 0.88), validation set (R2 = 0.95), and true external test set (R2 = 0.92). The models were also internally validated by 5-fold cross-validation and Y-scrambling experiments, showing that the models have high levels of goodness-of-fit, robustness and predictivity. The contribution of descriptors to the toxicity in the models was assessed using the Accumulated Local Effect (ALE) technique. The proposed approach provides an important tool to assess toxicity of nitroaromatic compounds, based on the ensemble QSAR model and the structural relationship to toxicity by analyzed contribution of the involved descriptors.

14.
Molecules ; 27(20)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36296373

RESUMO

Human serum paraoxonase-1 (PON1) is an important hydrolase-type enzyme found in numerous tissues. Notably, it can exist in two isozyme-forms, Q and R, that exhibit different activities. This study presents an in silico (QSAR, Docking, MD and QM/MM) study of a set of compounds on the activity towards the PON1 isoenzymes (QPON1 and RPON1). Different rates of reaction for the Q and R isoenzymes were analyzed by modelling the effect of Q192R mutation on active sites. It was concluded that the Q192R mutation is not even close to the active site, while it is still changing the geometry of it. Using the combined genetic algorithm with multiple linear regression (GA-MLR) technique, several QSAR models were developed and relative activity rates of the isozymes of PON1 explained. From these, two QSAR models were selected, one each for the QPON1 and RPON1. Best selected models are four-variable MLR models for both Q and R isozymes with squared correlation coefficient R2 values of 0.87 and 0.83, respectively. In addition, the applicability domain of the models was analyzed based on the Williams plot. The results were discussed in the light of the main factors that influence the hydrolysis activity of the PON1 isozymes.


Assuntos
Arildialquilfosfatase , Isoenzimas , Humanos , Arildialquilfosfatase/genética , Hidrólise , Isoenzimas/genética , Modelos Lineares , Análise Multivariada
15.
Curr Comput Aided Drug Des ; 18(7): 469-479, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36177632

RESUMO

INTRODUCTION: This report proposes the application of a new Machine Learning algorithm called Fuzzy Unordered Rules Induction Algorithm (FURIA)-C in the classification of druglike compounds with antidiabetic inhibitory ability toward the main two pharmacological targets: α-amylase and α-glucosidase. METHODS: The two obtained QSAR models were tested for classification capability, achieving satisfactory accuracy scores of 94.5% and 96.5%, respectively. Another important outcome was to achieve various α-amylase and α-glucosidase fuzzy rules with high Certainty Factor values. Fuzzyrules derived from the training series and active classification rules were interpreted. An important external validation step, comparing our method with those previously reported, was also included. RESULTS: The Holm's test comparison showed significant differences (p-value<0.05) between FURIA-C, Linear Discriminating Analysis (LDA), and Bayesian Networks, the former beating the two latter according to the relative ranking score of the Holm's test. CONCLUSION: From these results, the FURIA-C algorithm could be used as a cutting-edge technique to predict (classify or screen) the α-amylase and α-glucosidase inhibitory activity of new compounds and hence speed up the discovery of new potent multi-target antidiabetic agents.


Assuntos
Inibidores de Glicosídeo Hidrolases , alfa-Amilases , Inibidores de Glicosídeo Hidrolases/farmacologia , alfa-Amilases/metabolismo , alfa-Glucosidases , Relação Quantitativa Estrutura-Atividade , Teorema de Bayes , Hipoglicemiantes/farmacologia
16.
Mol Pharm ; 19(7): 2151-2163, 2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35671399

RESUMO

Antibacterial drugs (AD) change the metabolic status of bacteria, contributing to bacterial death. However, antibiotic resistance and the emergence of multidrug-resistant bacteria increase interest in understanding metabolic network (MN) mutations and the interaction of AD vs MN. In this study, we employed the IFPTML = Information Fusion (IF) + Perturbation Theory (PT) + Machine Learning (ML) algorithm on a huge dataset from the ChEMBL database, which contains >155,000 AD assays vs >40 MNs of multiple bacteria species. We built a linear discriminant analysis (LDA) and 17 ML models centered on the linear index and based on atoms to predict antibacterial compounds. The IFPTML-LDA model presented the following results for the training subset: specificity (Sp) = 76% out of 70,000 cases, sensitivity (Sn) = 70%, and Accuracy (Acc) = 73%. The same model also presented the following results for the validation subsets: Sp = 76%, Sn = 70%, and Acc = 73.1%. Among the IFPTML nonlinear models, the k nearest neighbors (KNN) showed the best results with Sn = 99.2%, Sp = 95.5%, Acc = 97.4%, and Area Under Receiver Operating Characteristic (AUROC) = 0.998 in training sets. In the validation series, the Random Forest had the best results: Sn = 93.96% and Sp = 87.02% (AUROC = 0.945). The IFPTML linear and nonlinear models regarding the ADs vs MNs have good statistical parameters, and they could contribute toward finding new metabolic mutations in antibiotic resistance and reducing time/costs in antibacterial drug research.


Assuntos
Antibacterianos , Aprendizado de Máquina , Algoritmos , Antibacterianos/farmacologia , Bases de Dados Factuais , Redes e Vias Metabólicas
17.
PLoS Negl Trop Dis ; 16(5): e0009867, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35551272

RESUMO

Snakebite is the only WHO-listed, not infectious neglected tropical disease (NTD), although its eco-epidemiology is similar to that of zoonotic infections: envenoming occurs after a vertebrate host contacts a human. Accordingly, snakebite risk represents the interaction between snake and human factors, but their quantification has been limited by data availability. Models of infectious disease transmission are instrumental for the mitigation of NTDs and zoonoses. Here, we represented snake-human interactions with disease transmission models to approximate geospatial estimates of snakebite incidence in Sri Lanka, a global hotspot. Snakebites and envenomings are described by the product of snake and human abundance, mirroring directly transmitted zoonoses. We found that human-snake contact rates vary according to land cover (surrogate of occupation and socioeconomic status), the impacts of humans and climate on snake abundance, and by snake species. Our findings show that modelling snakebite as zoonosis provides a mechanistic eco-epidemiological basis to understand snakebites, and the possible implications of global environmental and demographic change for the burden of snakebite.


Assuntos
Mordeduras de Serpentes , Animais , Antivenenos , Humanos , Incidência , Mordeduras de Serpentes/epidemiologia , Serpentes , Fatores Socioeconômicos , Zoonoses/epidemiologia
18.
Rev Esp Salud Publica ; 952021 Oct 13.
Artigo em Espanhol | MEDLINE | ID: mdl-34643186

RESUMO

OBJECTIVE: Low back pain in childhood and adolescence is considered a predictor of low back pain in adulthood. Sedentary lifestyle is associated with low back pain. This study evaluated the relationship between low back pain and screen time in adolescents 10 to 15 years. METHODS: Cross-sectional study involving schoolchildren 10 and 15 years from school centers of the urban area in Talavera de la Reina. Chi-square test was used to analyze the relationship between low back pain and time spent watching. A logistic regression adjusted for confounding variables was performed and represented by the Odds Ratio. Statistical significance was considered for p<0.05. RESULTS: A total of 1,278 surveys were completed. 31% of schoolchildren reported low back pain in the last 3 months. Statistically significant differences were observed between low back pain with respect to sex and sleep time. Moreover, differences were noticed in the proportion of school-children who report low back pain during the week and use screens more than 2 hours compared to those who report using screens less than 2 hours. These differences were not observed on weekends. CONCLUSIONS: Although adolescents spend more time in front of screens on weekends, the proportion of adolescents who report low back pain is higher during the week.


OBJETIVO: La presencia de dolor lumbar en la niñez y en la adolescencia se considera un predictor de padecer lumbalgia en la edad adulta. Existe evidencia que relaciona el sedentarismo de manera independiente con el dolor lumbar. El objetivo de este estudio fue evaluar la relación existente entre el dolor lumbar y el tiempo de uso de pantallas en adolescentes de 10 a 15 años. METODOS: Estudio transversal donde participaron escolares de entre 10 y 15 años de los centros educativos de la zona urbana de Talavera de la Reina. Para analizar la relación entre el dolor lumbar y el tiempo dedicado a la pantalla se utilizó la prueba de Chi-cuadrado. Se realizó una regresión logística ajustada por las posibles variables de confusión y representada por la Odds Ratio. Se consideró significación estadística si p<0,05. RESULTADOS: Un total de 1.278 encuestas fueron completadas. El 31% de los escolares referían dolor lumbar en los últimos 3 meses. Existen diferencias estadísticamente significativas entre el dolor lumbar con respecto al sexo y al número de horas de sueño. Existen diferencias en la proporción de escolares que refieren dolor lumbar entre semana y utilizan pantallas más de 2 horas en comparación a los que refieren el uso de pantallas menos de 2 horas. Estas diferencias no se observaron los fines de semana. CONCLUSIONES: Aunque los adolescentes pasan más tiempo delante de las pantallas los fines de semana, la proporción de adolescentes que refieren dolor lumbar es superior entre semana.


Assuntos
Dor Lombar , Adolescente , Adulto , Criança , Estudos Transversais , Humanos , Dor Lombar/epidemiologia , Tempo de Tela , Espanha , Inquéritos e Questionários
19.
Cells ; 10(7)2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34208834

RESUMO

Ischemic stroke is the second cause of mortality and the first cause of long-term disability constituting a serious socioeconomic burden worldwide. Approved treatments include thrombectomy and rtPA intravenous administration, which, despite their efficacy in some cases, are not suitable for a great proportion of patients. Glial cell-related therapies are progressively overcoming inefficient neuron-centered approaches in the preclinical phase. Exploiting the ability of microglia to naturally switch between detrimental and protective phenotypes represents a promising therapeutic treatment, in a similar way to what happens with astrocytes. However, the duality present in many of the roles of these cells upon ischemia poses a notorious difficulty in disentangling the precise pathways to target. Still, promoting M2/A2 microglia/astrocyte protective phenotypes and inhibiting M1/A1 neurotoxic profiles is globally rendering promising results in different in vivo models of stroke. On the other hand, described oligodendrogenesis after brain ischemia seems to be strictly beneficial, although these cells are the less studied players in the stroke paradigm and negative effects could be described for oligodendrocytes in the next years. Here, we review recent advances in understanding the precise role of mentioned glial cell types in the main pathological events of ischemic stroke, including inflammation, blood brain barrier integrity, excitotoxicity, reactive oxygen species management, metabolic support, and neurogenesis, among others, with a special attention to tested therapeutic approaches.


Assuntos
Isquemia Encefálica/terapia , Neuroglia/fisiologia , Traumatismo por Reperfusão/terapia , Animais , Barreira Hematoencefálica/patologia , Humanos , Neurogênese , Estresse Oxidativo
20.
Toxicon X ; 9-10: 100069, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34258577

RESUMO

Snakebite envenoming is a set of intoxication diseases that disproportionately affect people of poor socioeconomic backgrounds in tropical countries. As it is highly dependent on the environment its burden is expected to shift spatially with global anthropogenic environmental (climate, land use) and demographic change. The mechanisms underlying the changes to snakebite epidemiology are related to factors of snakes and humans. The distribution and abundance of snakes are expected to change with global warming via their thermal tolerance, while rainfall may affect the timing of key activities like feeding and reproduction. Human population growth is the primary cause of land-use change, which may impact snakes at smaller spatial scales than climate via habitat and biodiversity loss (e.g. prey availability). Human populations, on the other hand, could experience novel patterns and morbidity of snakebite envenoming, both as a result of snake responses to environmental change and due to the development of agricultural adaptations to climate change, socioeconomic and cultural changes, development and availability of better antivenoms, personal protective equipment, and mechanization of agriculture that mediate risk of encounters with snakes and their outcomes. The likely global effects of environmental and demographic change are thus context-dependent and could encompass both increasing and or snakebite burden (incidence, number of cases or morbidity), exposing new populations to snakes in temperate areas due to "tropicalization", or by land use change-induced snake biodiversity loss, respectively. Tackling global change requires drastic measures to ensure large-scale ecosystem functionality. However, as ecosystems represent the main source of venomous snakes their conservation should be accompanied by comprehensive public health campaigns. The challenges associated with the joint efforts of biodiversity conservation and public health professionals should be considered in the global sustainability agenda in a wider context that applies to neglected tropical and zoonotic and emerging diseases.

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