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1.
Environ Res ; 252(Pt 1): 118756, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38552830

RESUMEN

The evaluation of the ecotoxicological effects of the effluent after treatment with peracetic acid is relevant to help establish reference concentrations for the disinfection process and waste recovery. Therefore, the objective of this work was to evaluate the ecotoxicity of effluent from a bovine slaughterhouse treated with peracetic acid on Girardia tigrina. The toxicity bioassays for planaria were the acute test (LC50) and chronic assays: locomotion, regeneration, reproduction and fertility. The results showed that the effluent treated with peracetic acid showed less toxicity than the effluent without application of peracetic acid. The effluent after peracetic acid application showed a chronic toxic effect in the reduction of locomotor speed in all studied disinfectant concentrations (0.8, 1.6, 3.3 and 6.6 µg L-1 of peracetic acid) and a delay in the formation of G. tigrina photoreceptors at the concentration of 6.6 µg L-1 of peracetic acid. Peracetic acid concentrations of 0.8, 1.6 and 3.3 µg L-1 were not toxic for blastema regeneration, photoreceptor and auricle formation, fecundity and fertility. In addition, this study assists in defining doses of peracetic acid to be recommended in order to ensure the wastewater disinfection process without causing harm to aquatic organisms.


Asunto(s)
Mataderos , Desinfectantes , Ácido Peracético , Contaminantes Químicos del Agua , Ácido Peracético/toxicidad , Animales , Bovinos , Desinfectantes/toxicidad , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis , Desinfección/métodos , Aguas Residuales/toxicidad
2.
Int Braz J Urol ; 50(5): 605-615, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39106116

RESUMEN

OBJECTIVES: To evaluate the impact of COVID-19 pandemics on clinical and surgical practice, educational activities, health and lifestyle behavior of Brazilian urology residents after 1 year of socio-economic restrictions. MATERIALS AND METHODS: An electronic survey was e-mailed to all postgraduate (PG) students registered by the Brazilian Society of Urology. The survey inclu-ded an assessment of socio-demographic, clinical practice, educational, health-related and behavior parameters. We also evaluated which subareas of urology were predominantly affected. A similar survey was adapted and sent to the directors of all urology residency programs. RESULTS: COVID-19 pandemic has severely impacted the clinical, surgical, and educational activities of urology residents in Brazil. Urology residents reported >50% decrease in multiple surgical modalities. We highlight kidney transplantation surgeries (66.2%), minor surgeries (62.3%), endoscopic surgeries (42.6%) and reconstructive surgeries (38.8%). This could represent a critical skills gap that residents may face beyond the COVID-19 pandemic. Furthermore, PG students faced stressful situations that caused worsening of mental and physical health, such as getting redirected to assistance of COVID-19 patients (66.9%), and high rate of infection by SARS-CoV-2 (58.2%). CONCLUSIONS: The COVID-19 pandemic has severely impacted the clinical, surgical, and educational activities of urology residents in Brazil. This could represent a critical skills gap that residents may face beyond the COVID-19 pandemic. PG students faced stressful situations that caused worsening of mental and physical health such as redirection to assistance of COVID-19 patients, concern about their own contamination and of family members.


Asunto(s)
COVID-19 , Internado y Residencia , Pandemias , Urología , COVID-19/epidemiología , Humanos , Internado y Residencia/estadística & datos numéricos , Urología/educación , Brasil/epidemiología , Masculino , Femenino , Encuestas y Cuestionarios , Adulto , SARS-CoV-2 , Procedimientos Quirúrgicos Urológicos/educación , Procedimientos Quirúrgicos Urológicos/estadística & datos numéricos , Educación de Postgrado en Medicina
3.
Curr Microbiol ; 80(4): 133, 2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36897421

RESUMEN

Health care-associated infections (HAIs) contribute to a significant rate of morbidity, mortality, and financial burden on health systems. These infections are caused by multidrug-resistant bacteria that produce biofilm as the main virulence factor. This study aimed to evaluate the effect of the copper-based metallic compounds [Cu(phen)(pz)NO2]Cl (I), [Cu(bpy)(pz)(NO2)]Cl (II), and [Cu(phen)(INA)NO2]Cl (III), where phen = phenanthroline, bpy = bipyridine, pz = pyrazinamide, and INA = isonicotinic acid, against planktonic cells and biofilms formation of Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli. The susceptibility of the microorganisms was evaluated by minimum inhibitory concentration (MIC), minimum bacterial concentration (MBC), and time-kill curve assay on planktonic cells. The biofilm formation was evaluated by biomass quantification through staining with crystal violet (CV), colony-forming units (CFUs) quantification, and biofilm metabolic activity determination by XTT assay. The compounds showed bacteriostatic and bactericidal activity on all microorganisms analyzed. Regarding the antibiofilm activity, all metallic compounds were able to reduce significantly the biofilm biomass, colony-forming units, and the metabolic activity of remaining cells, varying the efficient concentration according to the strain analyzed. Interestingly, compounds (I), (II) and (III) did not exhibit DNA degradation activity even with up to 100 µM of these metal complexes. On the other hand, complexes (I) and (III) showed a remarkable capacity to cleave DNA upon addition of glutathione, a reducing agent (CuII/CuI) that leads to reactive oxygen species (ROS) formation. The results presented in this study showed promising antimicrobial and antibiofilm effects.


Asunto(s)
Antiinfecciosos , Infección Hospitalaria , Humanos , Antibacterianos/farmacología , Cobre/farmacología , Dióxido de Nitrógeno/farmacología , Antiinfecciosos/farmacología , Bacterias , Biopelículas , Atención a la Salud , Pruebas de Sensibilidad Microbiana
4.
Cytokine ; 157: 155955, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35792283

RESUMEN

Dengue fever is a clinical manifestation of dengue virus (DENV) infection well defined by the intense host immune response with the development of high fever, anorexia, headache and muscle pain. Several immune mediators are involved in the pathophysiology of DENV infection, in which polymorphisms in immune molecule genes contribute with the susceptibility and severity of the infection. Several meta-analyses are available with significant findings in the association between genetic variants in immune-mediator genes and dengue, though the results may be false positive. Hence, to solve this issue, we have performed a systematic revaluation with Bayesian approaches to verify the false positive rate in these results. A systematic search was performed for meta-analytic studies on the aforementioned issue. The calculations of false positive report probability (FPRP) and the Bayesian false-discovery probability (BFDP) at the prior probability of 10-3 and 10-6 have been performed. To verify the methodological quality of the studies included, the evaluation by the Venice criteria was applied. In addition, gene-gene and protein-protein networks were designed. As results, seven meta-analyses on genetic variants in several immune-inflammatory mediator genes and DENV infection comprise the results. Only the polymorphisms in the TNF, MICB, PLCE1, VDR, CD32 and HLA-A genes were considered as noteworthy. There was a heterogeneity profile for the results on Venice criteria indicating variability in the methodological quality. The gene-gene and protein-protein networks showed these immune mediators as relevant players in the disease. We suggest these polymorphisms as potential biomarkers for the pathogenesis and immune response against DENV.


Asunto(s)
Dengue , Virosis , Teorema de Bayes , Dengue/genética , Predisposición Genética a la Enfermedad/genética , Humanos , Metaanálisis como Asunto , Polimorfismo Genético/genética
5.
Cytokine ; 138: 155361, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33223448

RESUMEN

Periodontitis is a high prevalent disease into the clinical dentistry. Genetic variations in interleukins (IL) genes were associated with chronic periodontitis (CP) and were focus of several meta-analyses. This study aimed to assess the noteworthiness in the meta-analyses by means of a Bayesian approach to determinate possible false report associations. A systematic search was performed for meta-analyses with associations between gene polymorphisms in interleukins and CP. The calculations for the False-Positive Rate Probability (FPRP) and the Bayesian False Discovery Probability (BFDP) were performed to assess the noteworthiness with a statistical power of 1.2 and 1.5 of Odds Ratio at a prior probability of 10-3 and 10-6. As results, eight meta-analyses approaching the IL1A/rs1800587, IL1B/rs1143634, IL1RN/rs2234663, IL4/rs2243250, IL6/rs1800795/rs1800796, IL17A/rs2275913 and IL18/rs1946518/rs187238 polymorphisms have been identified. Twenty-two from 270 calculations (8.15%) were noteworthy. Herein, we have identified the IL1A and IL1B polymorphisms as noteworthy biomarkers for CP susceptibility.


Asunto(s)
Periodontitis Crónica/genética , Predisposición Genética a la Enfermedad , Interleucina-1beta/genética , Polimorfismo de Nucleótido Simple , Teorema de Bayes , Biomarcadores/metabolismo , Reacciones Falso Positivas , Humanos , Mediadores de Inflamación , Metaanálisis como Asunto , Oportunidad Relativa , Probabilidad
6.
Gastrointest Endosc ; 93(3): 704-711.e3, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33160978

RESUMEN

BACKGROUND AND AIMS: Endoscopists experience upper extremity musculoskeletal injuries. The primary aim of this study was to compare distal upper extremity biomechanical risk factors during colonoscopy with established risk thresholds. Secondary aims were to determine which subtasks during colonoscopy are associated with the greatest risk and to evaluate an intervention to reduce risks. METHODS: Twelve endoscopists performed 2 to 4 colonoscopies while thumb pinch force and forearm muscle loads of extensor carpi radialis (ECR) and flexor digitorum superficialis (FDS) muscles were collected. Peak exertion values were analyzed using amplitude probability distribution functions. An endoscope support device was evaluated during simulated colonoscopy (n = 8). RESULTS: Mean endoscopist age was 42.3 years; 67% were men. Peak thumb pinch force exceeded risk thresholds for pinch force (10 N) and percent of time spent in forceful pinch for all colonoscopy subtasks. Peak ECR and FDS muscle activity exceeded the action limit (10% maximum voluntary contraction [MVC]) in both forearms. Peak left FDS, left ECR, and right ECR activity exceeded the threshold limit value (>30% MVC). Peak left FDS and ECR activity were significantly greater during insertion than during withdrawal (P < .05). Peak right FDS and ECR activity were significantly greater during right colon insertion compared with withdrawal (P < .05). The endoscope support device reduced left ECR muscle activity (P = .02). CONCLUSIONS: Thumb pinch forces and time spent in forceful pinch indicate high-risk exposures during colonoscopy. Left wrist extensor muscle activity exceeded established thresholds with the greatest risk occurring during insertion. An endoscope support device reduced loads to the left wrist extensors.


Asunto(s)
Antebrazo , Enfermedades Musculoesqueléticas , Adulto , Colonoscopía , Electromiografía , Femenino , Humanos , Masculino , Enfermedades Musculoesqueléticas/etiología , Factores de Riesgo
7.
Curr Microbiol ; 78(5): 1926-1938, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33782740

RESUMEN

A large number of infections are caused by Gram-positive and Gram-negative multi-resistant bacteria worldwide, adding up to a figure of around 700,000 deaths per year. The indiscriminate uses of antibiotics, as well as their misuse, resulted in the selection of bacteria resistant to known antibiotics, for which it has little or no treatment. In this way, the strategies to combat the resistance of microorganisms are extremely important and, essential oils of Croton species have been extensively studied for this purpose. The aim of this study was to carry the evaluation of antibacterial, antibiofilm, antioxidant activities, and spectroscopic investigation of essential oil from Croton piauhiensis (EOCp). The EOCp exhibited antimicrobial activity against Gram-positive and Gram-negative bacteria with required MICs ranging from 0.15 to 5% (v/v). In addition, the MBC of the EOCp for Staphylococcus aureus ATCC 25923 and ATCC 700698, were 0.15 and 1.25%, respectively. Moreover, the EOCp significantly reduced significantly the biofilm production and the number of viable cells from the biofilm of all bacterial strains tested. The antioxidant potential of the EOCp showed EC50 values ranging from 171.21 to 4623.83 µg/mL. The EOCp caused hemolysis (>45%) at the higher concentrations tested (1.25 to 5%), and minor hemolysis (17.6%) at a concentration of 0.07%. In addition, docking studies indicated D-limonene as a phytochemical with potential for antimicrobial activity. This study indicated that the EOCp may be a potential agent against infections caused by bacterial biofilms, and act as a protective agent against ROS and oxidative stress.


Asunto(s)
Antiinfecciosos , Croton , Aceites Volátiles , Antibacterianos/farmacología , Antioxidantes/farmacología , Biopelículas , Bacterias Gramnegativas , Bacterias Grampositivas , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/farmacología
8.
J Neurovirol ; 26(1): 122-126, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31428990

RESUMEN

The Chikungunya virus (CHIKV) is an arbovirus transmitted to humans through mosquito bites and can cause a series of symptoms ranging from a benign febrile illness to severe neurological conditions. We report the identification of CHIKV in a serum sample from an elderly woman with febrile illness and severe arthralgia in Brazil. The occurrence was found of peripheral polyneuropathy affecting the upper and lower limbs evidenced by electroneuromyographic findings. The patient was treated with a corticoid associated with methotrexate, suggesting that the pathophysiological basis of the case in question may be related to an immune-mediated response by T cells and inflammatory cytokines. This finding reinforces the need to be aware of the emergence of neuroinfections related to CHIKV and effective diagnoses for the early detection of neurological alterations, favoring the clinical management of these patients.


Asunto(s)
Fiebre Chikungunya/complicaciones , Polineuropatías/virología , Anciano , Brasil , Femenino , Humanos , Inmunosupresores/uso terapéutico , Metotrexato/uso terapéutico , Polineuropatías/tratamiento farmacológico
9.
Cytokine ; 134: 155183, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32731142

RESUMEN

Dengue is an acute viral disease whose clinical condition is related to the interaction of factors related to the Dengue virus (DENV), environment and the host, with the immunity of the human host contributing a substantial role in the pathogenesis of DENV infection. Studies have demonstrated that single nucleotide polymorphisms (SNPs) in the promoter regions of cytokine genes such as tumor necrosis factor (TNF-α) affect transcription and/or expression; and therefore, may influence the pathogenesis of infectious diseases, such as dengue. Consequently, the objective of this study was to assess through a case-control study whether there was an association between the presence of SNPs -308G/A and -238G/A in the TNF-α gene and 158 patients with dengue and 123 controls. No association was found between the SNPs and the dengue cases in the study population. We then performed a meta-analysis, retrieving data from case-control studies in the literature for the same polymorphisms. For SNP-308G/A, the GG genotype was associated with dengue fever (DF) risk (OR = 1.24, 1.00-1.53; p = 0.05; I2 = 0%), while the GA genotype (OR = 0.75, 0.60-0.93; p = 0.01; I2 = 0%) and allele A (OR = 0.75, 0.60-0.93; p = 0.01; I2 = 0%) were associated with protection. The genotype GG population in the Asian continent (OR = 1.81 [1.06, 3.09], p = 0.03, I2 = 0%) and American (OR = 1.29 [1.00, 1.65], p = 0.05, I2 = 0%) was also associated with protection in the comparison between the cases versus the control group. In each comparison, the dominant model AA + GA (p < 0.00001) conferred protection. For SNP-238G/A the GA genotype was associated with risk for dengue hemorrhagic fever (DHF; OR = 2.17, 1.28-3.67; p = 0.004; I2 = 0%)), and the dominant AA + GA model (p < 0.00001) was associated with protection in each comparison. In summary, our results did not associate SNPs in the TNF-α gene to dengue in the Brazilian northeast population. However, combined literature data suggested the effect of the GG and GA genotypes of the SNP-308G/A on risk and protection, respectively, in Asian and American populations.


Asunto(s)
Dengue/genética , Polimorfismo de Nucleótido Simple , Factor de Necrosis Tumoral alfa/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Frecuencia de los Genes , Humanos , Lactante , Masculino , Persona de Mediana Edad , Adulto Joven
10.
Microb Pathog ; 135: 103608, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31229603

RESUMEN

This study aimed to determinate the chemical composition and evaluate the antimicrobial and antioxidant activity of the essential oil obtained from leaves of V. gardneriana. The Vitex gardneriana leaves's were hydrodistilled to obtain the essential oil and the chemical composition determined by GC/MS analysis. The antimicrobial activities were determined by microdilution method. The activity of essential oil on biofilm was evaluated by quantification of total biomass and enumeration of biofilm-entrapped viable cells. The antioxidant activity was assessed by DPPH free radical assay, ferrous ion chelating assay, ferric-reducing antioxidant power and ß-carotene bleaching assay. Furthermore, the essential oil was tested on viability of health human, animal cells and the microcrustacean Artemia sp. The essential oil showed high content of sesquiterpenes and very low content of monoterpenes. Regarding activity on planktonic cells, the essential oil reduced the growth of the all species tested but showed MIC values only to S. aureus (0.31%). In general, the essential oil reduced significantly the biofilm biomass and the number of viable cells of bacteria and yeasts, mainly on biofilm formation. The essential oil showed a potential antioxidant activity, mainly on ß-carotene oxidation. Moreover, the essential oil reduced the cell viability of murine fibroblasts but not show viability reduction of human keratinocytes. Furthermore, the oil not show toxicity against the microcrustacean. Thus, the essential oil from V. gardneriana leaves may be considered as an important alternative against biofilms formed by bacteria and yeasts related to infections, as well as a natural antioxidant and non-toxic substance on human cells.


Asunto(s)
Antiinfecciosos/química , Antioxidantes/química , Aceites Volátiles/química , Extractos Vegetales/química , Hojas de la Planta/química , Vitex/química , Animales , Antiinfecciosos/farmacología , Artemia/efectos de los fármacos , Bacterias/efectos de los fármacos , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Brasil , Candida/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Monoterpenos/química , Aceites Volátiles/aislamiento & purificación , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , beta Caroteno
11.
An Acad Bras Cienc ; 91(2): e20180204, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31038534

RESUMEN

This study evaluated the antibacterial, antifungal, and antioxidant effect of 7-hydroxy-4',6-dimethoxy-isoflavone and essential oil of Myroxylon peruiferum. The compound was isolated and its structure elucidated by NMR. The chemical composition of essential oil determined by GC-MS analysis. To evaluation of antimicrobial activity, the Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC) and Minimum Fungicidal Concentration (MFC) were performed. In addition to analysis of antioxidant activity, DPPH radical scavenging tests, iron chelating assay (FIC), antioxidant reducing power assay (FRAP) and ß-carotene bleaching assay (BCB) were performed. For the essential oil were identified 24 organized compounds having as main constituents; Germacrene D (17.2%), α-pinene (14.8%) and E-caryophyllene (10.8%). The results showed that isoflavone (2000 to 156 µg/mL) and essential oil (5.0 to 1.25%) present antibacterial and antifungal activity against Gram-positive bacteria and filamentous fungi. The isoflavone and the essential oil also presented antioxidant activity in all the tests, mainly on inhibition of the oxidation of ß-carotene test concentrations ranging from 60 to 100%. In conclusion, isoflavone and essential oil from M. peruiferum present an antimicrobial alternative against Gram-positive bacteria, especially of the genus Staphylococcus and dermatophyte fungi of the genus Trichophyton, as well as a natural compound antioxidant.


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Myroxylon/química , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Antioxidantes/análisis , Bacterias/efectos de los fármacos , Hongos/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Quelantes del Hierro , Isoflavonas/análisis , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/química , Extractos Vegetales/química , Valores de Referencia , Reproducibilidad de los Resultados , Factores de Tiempo
12.
Immunogenetics ; 70(6): 355-362, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29164277

RESUMEN

Dengue is the most prevalent arthropod-borne viral illness in humans worldwide. Single-nucleotide polymorphisms (SNPs) in genes involved in the immune response, such as dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN), IgG Fc receptor II-A (FcγRIIa), vitamin D receptor (VDR), and tumor necrosis factor alpha (TNF-α), were previously reported to be associated with susceptibility to dengue disease in different human populations. Therefore, due to the relevant association of host immune and genetic status with disease susceptibility/severity of dengue, this work aims to verify the frequency of anti-dengue virus antibodies and some dengue-associated risk SNPs in a population in Minas Gerais State, Southeast Brazil. A total of 1560 individuals were genotyped for polymorphisms in DC-SIGN (rs4804803), FcγRIIa (rs1801274), VDR (rs7975232), and TNF-α (rs1800629). The presence of anti-dengue antibodies (IgM and/or IgG) in these samples was also assayed. Anti-dengue antibodies were detected at an overall frequency of 16.86%, indicating a virus infection in asymptomatic individuals. The genotypic frequencies of all SNPs studied did not differ between the asymptomatic and control groups. Regarding the allelic frequencies of the four SNPs analyzed, a higher frequency was detected of the G allele of FcγRIIa/rs1801274 in the asymptomatic individuals when compared to that in the control group (p = 0.03). Therefore, the results showed a high prevalence of asymptomatic individuals in Minas Gerais State, with a potential association between the presence of the G allele of FcγRIIa/rs1801274 and protection against symptomatic disease.


Asunto(s)
Dengue/genética , Dengue/inmunología , Receptores de IgG/genética , Adulto , Arginina/genética , Brasil , Moléculas de Adhesión Celular/genética , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Lectinas Tipo C/genética , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Prevalencia , Receptores de Calcitriol/genética , Receptores de Superficie Celular/genética , Factor de Necrosis Tumoral alfa/genética
13.
Arch Virol ; 162(10): 2971-2981, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28620810

RESUMEN

Usurpation of the host's signalling pathways is a common strategy employed by viruses to promote their successful replication. Here we show that infection with the orthopoxvirus vaccinia virus (VACV) leads to sustained stimulation of c-Jun activity during the entire infective cycle. This stimulation is temporally regulated through MEK/ERK or MKK/JNK pathways, i.e. during the early/mid phase (1 to 6 hpi) and in the late phase (9 to 24 hpi) of the infective cycle, respectively. As a transcriptional regulator, upon infection with VACV, c-Jun is translocated from the cytoplasm to the nucleus, where it binds to the AP-1 DNA sequence found at the promoter region of its target genes. To investigate the role played by c-Jun during VACV replication cycle, we generated cell lines that stably express a c-Jun-dominant negative (DNc-Jun) mutation. Our data revealed that c-Jun is required during early infection to assist with viral DNA replication, as demonstrated by the decreased amount of viral DNA found in the DNc-Jun cells. We also demonstrated that c-Jun regulates the expression of the early growth response gene (egr-1), a gene previously shown to affect VACV replication mediated by MEK/ERK signalling. VACV-induced stimulation of the MKK/JNK/JUN pathway impacts viral dissemination, as we observed a significant reduction in both viral yield, during late stages of infection, and virus plaque size. Collectively, our data suggest that, by modulating the host's signalling pathways through a common target such as c-Jun, VACV temporally regulates its infective cycle in order to successfully replicate and subsequently spread.


Asunto(s)
Quinasas MAP Reguladas por Señal Extracelular/metabolismo , MAP Quinasa Quinasa 4/metabolismo , Quinasas Quinasa Quinasa PAM/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Proteínas Proto-Oncogénicas c-jun/metabolismo , Virus Vaccinia/fisiología , Animales , Línea Celular , ADN Viral , Proteína 1 de la Respuesta de Crecimiento Precoz/genética , Proteína 1 de la Respuesta de Crecimiento Precoz/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/genética , Fibroblastos/virología , Regulación Enzimológica de la Expresión Génica/fisiología , Regulación Viral de la Expresión Génica/fisiología , MAP Quinasa Quinasa 4/genética , Quinasas Quinasa Quinasa PAM/genética , Ratones , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Fosforilación , Proteínas Proto-Oncogénicas c-jun/genética , Replicación Viral
14.
Hum Factors ; 57(7): 1188-94, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26002872

RESUMEN

OBJECTIVE: The aim of this study was to evaluate the effects of key gap (distance between edges of keys) on computer keyboards on typing speed, percentage error, preference, and usability. BACKGROUND: In Parts 1 and 2 of this series, a small key pitch (center-to-center distance between keys) was found to reduce productivity and usability, but the findings were confounded by gap. In this study, key gap was varied while holding key pitch constant. METHOD: Participants (N = 25) typed on six keyboards, which differed in gap between keys (1, 3, or 5 mm) and pitch (16 or 17 mm; distance between centers of keys), while typing speed, accuracy, usability, and preference were measured. RESULTS: There was no statistical interaction between gap and pitch. Accuracy was better for keyboards with a gap of 5 mm compared to a 1-mm gap (p = .04). Net typing speed (p = .02), accuracy (p = .002), and most usability measures were better for keyboards with a pitch of 17 mm compared to a 16-mm pitch. CONCLUSIONS: The study findings support keyboard designs with a gap between keys of 5 mm over 1 mm and a key pitch of 17 mm over 16 mm. APPLICATIONS: These findings may influence keyboard standards and design, especially the design of small keyboards used with portable devices, such as tablets and laptops.


Asunto(s)
Periféricos de Computador , Ergonomía/instrumentación , Sistemas Hombre-Máquina , Adulto , Diseño de Equipo , Femenino , Humanos , Masculino
15.
Int J Biol Macromol ; 258(Pt 1): 128894, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38134983

RESUMEN

Hemicellulose is widely available in nature, is a sustainable resource and has a wide range of applications. Among them, adsorption stands out for the removal of potentially toxic ions. Thus, in the study, the adsorption of Cd2+, Pb2+ and Hg2+ ions in two hemicellulose matrices were elucidated through computational simulations using density functional theory. Molecular electrostatic potential and frontier molecular orbitals demonstrated whether the interactions could happen. Four interaction complexes were highlighted due to the interaction energy criteria, ΔEBind, ΔH and ΔG < 0.00 kcal mol-1, that is: Hm1… Pb (1); Hm2… Pb (3); Hm2…Cd (4) and Hm2…Hg (4) and the results show that they occur through physisorption. In structural parameter studies, interaction distances smaller than 3000 Å were identified, which ranged from 2.253 Å to 2.972 Å. From the analysis of the topological parameters of QTAIM, it was possible to characterize the intensities of the interactions, as well as their nature, which were partially covalent or electrostatic in nature. Finally, based on the theoretical results, it can be affirmed that the hemicellulose can interact with Cd2+, Pb2+ and Hg2+ ions, evidencing that this study can support further experimental essays to remove contaminants from effluents.


Asunto(s)
Mercurio , Polisacáridos , Contaminantes Químicos del Agua , Cadmio/química , Plomo , Adsorción , Termodinámica , Iones , Modelos Teóricos , Contaminantes Químicos del Agua/análisis
16.
Comput Biol Chem ; 109: 108029, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38387123

RESUMEN

Cancer is a global public health problem characterized by deviations in the mechanisms that control cell proliferation, resulting in mutations and variations in the structure of DNA. The mechanisms of action of chemotherapeutic drugs are related to their interactions and binding with DNA; consequently, the development of antineoplastic agents that target DNA has extensively focused on use of acridine, a heterocyclic molecule that binds to deoxyribonucleic acid via intercalation, a process that modifies DNA and makes replication impossible. In this context, this study aimed to computationally investigate how acridine intercalators interact with DNA by evaluating the mechanism of interactions, binding, and interaction energies using quantum mechanics calculations. Molecular electrostatic potential (MEP) analysis revealed that acridine has well- distributed negative charges in the center of the molecule, indicative of a dominant electron-rich region. Acridine exhibits well-defined π orbitals (HOMO and LUMO) on the aromatic rings, suggesting that charge transfer occurs within the molecule and may be responsible for the pharmacological activity of the compound. Structural analysis revealed that acridine interacts with DNA mainly through hydrogen bonds between HAcridine… ODNA with bond lengths ranging from 2.370 Što 3.472 Å. The Binding energy (ΔEBind) showed that acridine interacts with DNA effectively for all complexes and the electronic energy results (E+ZPE) for complexes revealed that the complexes are more stable when the DNA-centered acridine molecule. The Laplacian-analysis topological QTAIM parameter (∇2ρ(r)) and total energy (H(r)) categorized the interactions as being non-covalent in nature. The RGD peak distribution in the NCI analysis reveals the presence of van der Waals interactions, predominantly between the intercalator and DNA. Accordingly, we confirm that acridine/DNA interactions are relevant for understanding how the intercalator acts within nucleic acids.


Asunto(s)
Antineoplásicos , Sustancias Intercalantes , Sustancias Intercalantes/farmacología , Sustancias Intercalantes/química , Modelos Moleculares , Acridinas/farmacología , ADN/química , Antineoplásicos/farmacología
17.
Heliyon ; 10(13): e33885, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39071632

RESUMEN

Arboviruses are etiological agents in an extensive group of emerging diseases with great clinical relevance in Brazil, due to the wide distribution of their vectors and the favorable environmental conditions. Among them, the Mayaro virus (MAYV) has drawn attention since its emergence as the etiologic agent of Mayaro fever, a highly debilitating disease. To study viral replication and identify new drug candidates, traditional antiviral assays based on viral antigens and/or plaque assays have been demonstrating low throughput, making it difficult to carry out larger-scale assays. Therefore, we developed and characterized two DNA-launched infectious clones reporter viruses based on the MAYV strain BeAr 20290 containing the reporter genes of firefly luciferase (FLuc) and nanoluciferase (NLuc), designated as MAYV-firefly and MAYV-nanoluc, respectively. The viruses replicated efficiently with similar properties to the parental wild-type MAYV, and luminescence expression levels reflected viral replication. Reporter genes were also preserved during passage in cell culture, remaining stably expressed for one round of passage for MAYV-firefly and three rounds for MAYV-nanoluc. Employing the infectious clone, we described the effect of Rimantadine, an FDA-approved Alzheimer's drug, as a repurposing agent for MAYV but with a broad-spectrum activity against Zika virus infection. Additionally, we validated MAYV-nanoluc as a tool for antiviral drug screening using the compound EIDD-2749 (4'-Fluorouridine), which acts as an inhibitor of alphavirus RNA-dependent RNA polymerase.

18.
J Pharmacol Toxicol Methods ; 127: 107509, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38701958

RESUMEN

Myrcene (ß-myrcene), found in essential oils from plant species such as hops and cannabis, has many advantageous properties, but its use is limited due to volatility and low solubility in water. One way to circumvent these limitations is to encapsulate the essential oils in a polymer matrix. However, these hydrophobic molecules are difficult to quantify when dispersed in water. Seeking to study the release of this terpene in drug release tests from polymeric matrices, this work aimed to develop an easy and cheap UV spectrophotometric method for the quantification of ß-myrcene in aqueous medium. To achieves this goal, samples were prepared in 0.05% (w/v) polysorbate 80 solution, with concentrations of ß-myrcene ranging from 0.01% to 0.1% (v/v), and were analyzed at 226 nm. Each sample was analyzed in triplicate and repeated on three different days, to evaluate the repeatability of the results. The results were subjected to Q, F and Student's t-tests. The regression parameters obtained for ß-myrcene were above 0.99 and through statistical analysis, it was possible to confirm the repeatability for the results. The values of the limits of detection and quantification indicated that the method is not affected by intrinsic factors of the equipment. The results of accuracy, robustness and selectivity showed recovery rates within acceptable limits. This demonstrates that the quantification of ß-myrcene in aqueous medium by UV spectrophotometry is feasible.


Asunto(s)
Quitosano , Espectrofotometría Ultravioleta , Agua , Espectrofotometría Ultravioleta/métodos , Agua/química , Quitosano/química , Monoterpenos Acíclicos/análisis , Monoterpenos Acíclicos/química , Alquenos/análisis , Alquenos/química , Polisorbatos/química , Polisorbatos/análisis , Solubilidad , Reproducibilidad de los Resultados , Aceites Volátiles/análisis , Aceites Volátiles/química
19.
J Virol ; 86(1): 172-84, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22031940

RESUMEN

Viral manipulation of transduction pathways associated with key cellular functions such as survival, response to microbial infection, and cytoskeleton reorganization can provide the supportive milieu for a productive infection. Here, we demonstrate that vaccinia virus (VACV) infection leads to activation of the stress-activated protein kinase (SAPK)/extracellular signal-regulated kinase (ERK) 4/7 (MKK4/7)-c-Jun N-terminal protein kinase 1/2 (JNK1/2) pathway; further, the stimulation of this pathway requires postpenetration, prereplicative events in the viral replication cycle. Although the formation of intracellular mature virus (IMV) was not affected in MKK4/7- or JNK1/2-knockout (KO) cells, we did note an accentuated deregulation of microtubule and actin network organization in infected JNK1/2-KO cells. This was followed by deregulated viral trafficking to the periphery and enhanced enveloped particle release. Furthermore, VACV infection induced alterations in the cell contractility and morphology, and cell migration was reduced in the JNK-KO cells. In addition, phosphorylation of proteins implicated with early cell contractility and cell migration, such as microtubule-associated protein 1B and paxillin, respectively, was not detected in the VACV-infected KO cells. In sum, our findings uncover a regulatory role played by the MKK4/7-JNK1/2 pathway in cytoskeleton reorganization during VACV infection.


Asunto(s)
Citoesqueleto/metabolismo , MAP Quinasa Quinasa 4/metabolismo , MAP Quinasa Quinasa 7/metabolismo , Sistema de Señalización de MAP Quinasas , Proteína Quinasa 8 Activada por Mitógenos/metabolismo , Proteína Quinasa 9 Activada por Mitógenos/metabolismo , Virus Vaccinia/fisiología , Vaccinia/enzimología , Animales , Movimiento Celular , Citoesqueleto/genética , Humanos , MAP Quinasa Quinasa 4/genética , MAP Quinasa Quinasa 7/genética , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Proteína Quinasa 8 Activada por Mitógenos/genética , Proteína Quinasa 9 Activada por Mitógenos/genética , Fosforilación , Vaccinia/genética , Vaccinia/fisiopatología , Vaccinia/virología , Virus Vaccinia/genética
20.
Ergonomics ; 56(9): 1363-75, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23909815

RESUMEN

The purpose of this study was to evaluate tablet size (weight), orientation, grip shape, texture and stylus shape on productivity, biomechanics and subjective usability and fatigue when the tablet was held with just the left hand. A total of 15 male and 15 female subjects, ages 16-64 years, tested eight tablets and three styluses. Overall, the usability, fatigue and biomechanical evaluation of tablet design features supported the use of smaller to medium-sized tablets, with a ledge or handle shape on the back and surfaced with a rubberised texture. Larger, heavier tablets had significantly worse usability and biomechanics and their use with one hand should be limited. The stylus with a tapered grip (7.5-9.5 mm) or larger grip (7.6 mm) had better usability and biomechanics than one with a smaller grip (5 mm). There were no significant differences in productivity between design features. These design parameters may be important when designing tablets. PRACTITIONER SUMMARY: Different tablet and stylus design features were evaluated for usability and biomechanical properties. On the basis of short-term tasks, emulating functional tablets, usability was improved with the smaller and medium-sized tablets, portrait (vs. landscape) orientation, a back ledge grip and rubberised texture. There were no differences in productivity between design features.


Asunto(s)
Computadoras de Mano , Mano/anatomía & histología , Adolescente , Adulto , Fenómenos Biomecánicos , Periféricos de Computador , Diseño de Equipo , Ergonomía , Femenino , Mano/fisiología , Humanos , Masculino , Persona de Mediana Edad , Fatiga Muscular , Postura , Extremidad Superior/fisiología , Soporte de Peso , Adulto Joven
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