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1.
Toxins (Basel) ; 16(2)2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-38393182

RESUMO

Snakebite accident treatment requires the administration of antivenoms that provide efficacy and effectiveness against several snake venoms of the same genus or family. The low number of immunogenic components in venom mixtures that allow the production of antivenoms consequently gives them partial neutralization and a suboptimal pharmacological response. This study evaluates the immunorecognition and neutralizing efficacy of the polyvalent anticoral antivenom from the Instituto Nacional de Salud (INS) of Colombia against the heterologous endemic venoms of Micrurus medemi, and M. sangilensis, and M. helleri by assessing immunoreactivity through affinity chromatography, ELISA, Western blot, and neutralization capability. Immunorecognition towards the venoms of M. medemi and M. sangilensis showed values of 62% and 68% of the protein composition according to the immunoaffinity matrix, respectively. The analysis by Western blot depicted the highest recognition patterns for M. medemi, followed by M. sangilensis, and finally by M. helleri. These findings suggest that the venom compositions are closely related and exhibit similar recognition by the antivenom. According to enzyme immunoassays, M. helleri requires a higher amount of antivenom to achieve recognition than the others. Besides reinforcing the evaluation of INS antivenom capability, this work recommends the use of M. helleri in the production of Colombian antisera.


Assuntos
Antivenenos , Cobras Corais , Animais , Cobras Corais/metabolismo , Colômbia , Venenos Elapídicos/química , Venenos de Serpentes/química
2.
Brain Sci ; 13(6)2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37371349

RESUMO

Glioblastoma is the most aggressive and lethal brain tumor in adults, presenting diffuse brain infiltration, necrosis, and drug resistance. Although new drugs have been approved for recurrent patients, the median survival rate is two years; therefore, new alternatives to treat these patients are required. Previous studies have reported the anticancer activity of albendazole, its active metabolite albendazole sulfoxide, and melatonin; therefore, the present study was performed to evaluate if the combination of melatonin with albendazole or with albendazole sulfoxide induces an additive or synergistic cytotoxic effect on C6 and RG2 rat glioma cells, as well as on U87 human glioblastoma cells. Drug interaction was determined by the Chou-Talalay method. We evaluated the mechanism of cell death by flow cytometry, immunofluorescence, and crystal violet staining. The cytotoxicity of the combinations was mainly synergistic. The combined treatments induced significantly more apoptotic and autophagic cell death on the glioma cell lines. Additionally, albendazole and albendazole sulfoxide inhibited proliferation independently of melatonin. Our data justify continuing with the evaluation of this proposal since the combinations could be a potential strategy to aid in the treatment of glioblastoma.

3.
Nutrients ; 10(11)2018 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-30423806

RESUMO

It has been widely described that chronic intake of fructose causes metabolic alterations which can be associated with brain function impairment. In this study, we evaluated the effects of fructose intake on the sleep⁻wake cycle, locomotion, and neurochemical parameters in Wistar rats. The experimental group was fed with 10% fructose in drinking water for five weeks. After treatment, metabolic indicators were quantified in blood. Electroencephalographic recordings were used to evaluate the sleep architecture and the spectral power of frequency bands. Likewise, the locomotor activity and the concentrations of orexin A and monoamines were estimated. Our results show that fructose diet significantly increased the blood levels of glucose, cholesterol, and triglycerides. Fructose modified the sleep⁻wake cycle of rats, increasing the waking duration and conversely decreasing the non-rapid eye movement sleep. Furthermore, these effects were accompanied by increases of the spectral power at different frequency bands. Chronic consumption of fructose caused a slight increase in the locomotor activity as well as an increase of orexin A and dopamine levels in the hypothalamus and brainstem. Specifically, immunoreactivity for orexin A was increased in the ventral tegmental area after the intake of fructose. Our study suggests that fructose induces metabolic changes and stimulates the activity of orexinergic and dopaminergic neurons, which may be responsible for alterations of the sleep⁻wake cycle.


Assuntos
Encéfalo/efeitos dos fármacos , Açúcares da Dieta/farmacologia , Dopamina/metabolismo , Comportamento Alimentar , Frutose/farmacologia , Orexinas/metabolismo , Sono/efeitos dos fármacos , Animais , Glicemia/metabolismo , Encéfalo/citologia , Encéfalo/metabolismo , Tronco Encefálico/efeitos dos fármacos , Tronco Encefálico/metabolismo , Dieta , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Lipídeos/sangue , Locomoção/efeitos dos fármacos , Masculino , Atividade Motora/efeitos dos fármacos , Ratos Wistar , Fases do Sono/efeitos dos fármacos , Área Tegmentar Ventral/efeitos dos fármacos , Área Tegmentar Ventral/metabolismo , Vigília/efeitos dos fármacos
4.
Rev Chil Pediatr ; 89(3): 352-360, 2018 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-29999141

RESUMO

INTRODUCTION: Children, teenagers and young men are increasingly experiencing their well-being related to the internet and the new digital technologies. The objective of this study is to describe the presence of Cyberbullying, Sexting and Grooming in students in Chile according to gender and type of school management or administrative dependency. SUBJECTS AND METHOD: Exploratory and descriptive study. The sample design was non-probabilistic by quotas in 60 transactional establish ments. The sample was weighted considering the age range and gender according to national data. The Digital Literacy Questionnaire "Divergente-SerDigital" (2010) was applied to a sample of 12,926 students, aged 5 to 18 years. 4,790 men and 8,136 women. Average age 13.17 years. Frequencies were analyzed and the Chi-squared contrast statistic was used to determine statistically significant differences. RESULTS: The item Total Grooming (cheating) is presented as the main risk, 12.6% in municipal dependent schools (MDS), 8.2% in subsidized private schools (SPS), and 8.4% in private schools (PS). When considering gender, Grooming is observed mainly in Men, 20.4% in MDS, 19.9% in SPS and, 16.9% in PS. It is noteworthy that Women perform less Cyberbullying (active) according to school administration with 4.2% in MDS, 2.4% in SPS and, 2.6% in PS, with statistically significant differences (p < 0.05) in relation to Men. It also highlights the indicator Sexting (send) in Men, higher in PS with 10.6%. CONCLUSION: Grooming, Cyberbullying and Sexting risks are presented in the three types of administration with specific characteristics. These data can be a guide to work in promotion and prevention as well as in the schematization of cases according to type of school administration.


Assuntos
Bullying/estatística & dados numéricos , Internet , Instituições Acadêmicas/organização & administração , Assédio Sexual/estatística & dados numéricos , Envio de Mensagens de Texto/estatística & dados numéricos , Adolescente , Criança , Pré-Escolar , Chile , Feminino , Humanos , Masculino , Fatores Sexuais
5.
Rev. chil. pediatr ; 89(3): 352-360, jun. 2018. tab
Artigo em Espanhol | LILACS | ID: biblio-959533

RESUMO

INTRODUCCIÓN: Niños y adolescentes experimentan su bienestar cada día más relacionado con internet y las nuevas tecnologías digitales. El objetivo del manuscrito es describir la presencia de Ciberbullying (acoso o agresión entre menores o pares en internet), Sexting (difundir intimidad sexual) y Groo ming (engaño online a menores de edad por parte de adultos) en los estudiantes en Chile según sexo y tipo de administración escolar. SUJETOS Y MÉTODO: Estudio de carácter exploratorio y descriptivo. El diseño muestral fue no probabilístico por cuotas en 60 establecimientos de carácter transaccional. La muestra se ponderó considerando rango de edad y sexo según datos nacionales. Se aplicó el Cuestionario de Alfabetización Digital "Divergente-SerDigital" (2010) a una muestra de 12.926 estudiantes, rango de edad: 5 a 18 años. 4.790 hombres y 8.136 mujeres. Edad promedio 13,17 años. Se analizaron frecuencias y se utilizó el estadístico de contraste Chi cuadrado para determinar diferencias estadísticamente significativas. RESULTADOS: El ítem Grooming total (engaño) se presenta como el principal riesgo, 12,6% en Colegios Municipales (CM), 8,2% en Colegios Particulares Subvencionados (CPS) y 8,4% Colegios Particulares Privados (CPP). Al considerar el sexo se observa Grooming principal mente en Hombres, 20,4% en CM, 19,9% CPS y 16,9% CPP. Destaca que las Mujeres realizan menos Ciberbullying (activo) según administración escolar con 4,2% en CM, 2,4% CPS y 2,6% CPP, con diferencias estadísticamente significativa (p < 0,05) en relación a los Hombres. Además destaca el indicador Sexting (enviar) en Hombres, más alto en los CPP con 10,6%. CONCLUSIÓN: Los riesgos Grooming, Ciberbullying y Sexting se presentan en los tres tipos de administración con características específicas. Estos datos pueden ser guía del trabajo en promoción y prevención como en la tematización de casos según tipo de administración escolar.


INTRODUCTION: Children, teenagers and young men are increasingly experiencing their well-being related to the internet and the new digital technologies. The objective of this study is to describe the presence of Cyberbullying, Sexting and Grooming in students in Chile according to gender and type of school management or administrative dependency. SUBJECTS AND METHOD: Exploratory and descriptive study. The sample design was non-probabilistic by quotas in 60 transactional establish ments. The sample was weighted considering the age range and gender according to national data. The Digital Literacy Questionnaire "Divergente-SerDigital" (2010) was applied to a sample of 12,926 students, aged 5 to 18 years. 4,790 men and 8,136 women. Average age 13.17 years. Frequencies were analyzed and the Chi-squared contrast statistic was used to determine statistically significant differences. RESULTS: The item Total Grooming (cheating) is presented as the main risk, 12.6% in municipal dependent schools (MDS), 8.2% in subsidized private schools (SPS), and 8.4% in private schools (PS). When considering gender, Grooming is observed mainly in Men, 20.4% in MDS, 19.9% in SPS and, 16.9% in PS. It is noteworthy that Women perform less Cyberbullying (active) according to school administration with 4.2% in MDS, 2.4% in SPS and, 2.6% in PS, with statistically significant differences (p < 0.05) in relation to Men. It also highlights the indicator Sexting (send) in Men, higher in PS with 10.6%. CONCLUSION: Grooming, Cyberbullying and Sexting risks are presented in the three types of administration with specific characteristics. These data can be a guide to work in promotion and prevention as well as in the schematization of cases according to type of school administration.


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Instituições Acadêmicas/organização & administração , Assédio Sexual/estatística & dados numéricos , Internet , Bullying/estatística & dados numéricos , Envio de Mensagens de Texto/estatística & dados numéricos , Chile , Fatores Sexuais
6.
Rev Neurosci ; 24(3): 337-52, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23585211

RESUMO

Ozone (O3) is a component of photochemical smog, which is a major air pollutant and demonstrates properties that are harmful to health because of the toxic properties that are inherent to its powerful oxidizing capabilities. Environmental O3 exposure is associated with many symptoms related to respiratory disorders, which include loss of lung function, exacerbation of asthma, airway damage, and lung inflammation. The effects of O3 are not restricted to the respiratory system or function - adverse effects within the central nervous system (CNS) such as decreased cognitive response, decrease in motor activity, headaches, disturbances in the sleep-wake cycle, neuronal dysfunctions, cell degeneration, and neurochemical alterations have also been described; furthermore, it has also been proposed that O3 could have epigenetic effects. O3 exposure induces the reactive chemical species in the lungs, but the short half-life of these chemical species has led some authors to attribute the injurious mechanisms observed within the lungs to inflammatory processes. However, the damage to the CNS induced by O3 exposure is not well understood. In this review, the basic mechanisms of inflammation and activation of the immune system by O3 exposure are described and the potential mechanisms of damage, which include neuroinflammation and oxidative stress, and the signs and symptoms of disturbances within the CNS caused by environmental O3 exposure are discussed.


Assuntos
Sistema Nervoso/efeitos dos fármacos , Oxidantes Fotoquímicos/toxicidade , Ozônio/toxicidade , Poluentes Atmosféricos/toxicidade , Animais , Exposição Ambiental , Humanos , Sistema Nervoso/metabolismo , Pneumonia/induzido quimicamente , Pneumonia/metabolismo
7.
Microb Pathog ; 39(3): 97-107, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16098710

RESUMO

Identification of mycobacterial adhesins is needed to understand better the pathogenesis of tuberculosis and to develop new strategies to fight this infection. In this work, THP-1 monocytic cells were incubated with Mycobacterium tuberculosis culture filtrate proteins labelled with biotin and a dominant 19-kDa adhesin was found. This adhesin was characterized as the glycosylated and acylated 19-kDa antigen (Rv 3763). These findings were confirmed in assays with culture filtrate proteins and cell-wall fractions from a recombinant Mycobacterium smegmatis strain that overexpresses the 19-kDa antigen. Further, fluorescent microspheres coated with recombinant culture filtrate proteins adhere to cells in higher numbers than microspheres coated with native M. smegmatis proteins. The binding of the 19-kDa antigen to cells was inhibited with mannose receptor competitor sugars, Ca(2+) chelators and with a monoclonal antibody to the human mannose receptor. Phagocytosis assays showed high-level binding of bacilli to THP-1 cells that was inhibited with alpha-methyl-mannoside, mannan, EDTA and mAbs to the mannose receptor and to the 19-kDa M. tuberculosis antigen. Immunoprecipitation, cell-surface ELISA and immunostaining confirmed the expression of the mannose receptor by THP-1 cells. In conclusion, here we show that the macrophage mannose receptor, considered a pathogen pattern recognition receptor, may interact with mannose residues of mycobacterial glycoproteins that could promote the phagocytosis of mycobacteria.


Assuntos
Adesinas Bacterianas/imunologia , Lectinas Tipo C/imunologia , Lectinas de Ligação a Manose/imunologia , Monócitos/imunologia , Mycobacterium tuberculosis/imunologia , Fagocitose/imunologia , Receptores de Superfície Celular/imunologia , Tuberculose/microbiologia , Acetilglucosamina/farmacologia , Adesinas Bacterianas/metabolismo , Antígenos de Bactérias/imunologia , Aderência Bacteriana , Ensaio de Imunoadsorção Enzimática , Humanos , Immunoblotting , Imunoprecipitação , Lectinas Tipo C/metabolismo , Mananas/farmacologia , Receptor de Manose , Lectinas de Ligação a Manose/metabolismo , Metilmanosídeos/farmacologia , Monócitos/metabolismo , Monócitos/microbiologia , Mycobacterium tuberculosis/metabolismo , Ligação Proteica/imunologia , Receptores de Superfície Celular/metabolismo
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