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1.
Front Neurol ; 15: 1385945, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38784912

RESUMO

Background: Guillain-Barré syndrome (GBS) frequently leads to respiratory failure and autonomic dysfunction, resulting in approximately one-third of patients requiring mechanical ventilation. Objective: This study aimed to identify clinical predictors for mechanical ventilation in patients with GBS. Methods: This research was conducted from 2010 to 2021 using registries from a tertiary hospital in an upper middle-income Latin American country. Participants were categorized into two groups based on their ventilation status. Demographic data were collected, and independent predictors of the need for mechanical ventilation were determined through multivariate logistic regression analysis. Results: Dysautonomic events occurred in 36% of the patients, with 17% requiring mechanical ventilation; the average duration of intubation was 1.16 ± 3.18 days. The multivariate analysis indicated that bulbar dysfunction significantly increased the likelihood of requiring mechanical ventilation by 19-fold (OR 18.67, 95% CI 5.85-59.42), followed by ophthalmoplegia, which increased the likelihood by sixfold (OR 5.68, 95% CI 1.28-25.19). Conclusion: Bulbar dysfunction, dysautonomia, and lower Medical Research Council (MRC) scores were significant predictors of the need for mechanical ventilation in hospitalized GBS patients. These findings support the need for close monitoring and early admission to the intensive care unit (ICU) admission for at-risk patients.

2.
Biomed Pharmacother ; 173: 116307, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38401521

RESUMO

Chagas disease (CHD) is the highest economic burden parasitosis worldwide and the most important cardiac infection, without therapeutic alternatives to halt or reverse its progression. In CHD-experimental models, antioxidant and anti-inflammatory compounds have demonstrated therapeutic potential in cardiac dysfunction. Theobroma cacao polyphenols are potent natural antioxidants with cardioprotective and anti-inflammatory action, which are susceptible to degradation, requiring technological approaches to guarantee their protection, stability, and controlled release. Here, 21 cocoa polyphenol-rich microencapsulates were produced by spray-drying and freeze-drying techniques using two wall materials (maltodextrin and gum arabic). Chemical (total and individual phenolic content and antioxidant activity), structural (morphology), and biological parameters (cytotoxicity, trypanocidal, antioxidant, and immunomodulatory activities) were assessed to determine the most efficient microencapsulation conditions on Trypanosoma cruzi-infected myocardioblast and macrophage cells. Significant antiproliferative properties against infected cells (superior to benznidazole) were found in two microencapsulates which also exhibited cardioprotective properties against oxidative stress, inflammation, and cell death.


Assuntos
Cacau , Trypanosoma cruzi , Humanos , Polifenóis/farmacologia , Polifenóis/química , Antioxidantes/farmacologia , Antioxidantes/química , Cacau/química , Anti-Inflamatórios
4.
Langmuir ; 39(47): 16712-16720, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37960859

RESUMO

Mixed self-assembled monolayers (SAMs) are often used as highly tunable substrates for biomedical and biosensing applications. It is well documented, however, that mixed SAMs can be highly disordered at the molecular level and do not pack as closely or homogeneously as single-component SAMs, particularly when the chain lengths and head groups of the SAM thiol components are significantly different. In this study, we explore the impact of SAM structure and mixing ratio (-OH and -CH3 termini) on the weak physisorption behavior of bovine serum albumin (BSA), which adsorbs more readily to hydrophobic, methyl-terminated SAMs. Our results suggest that once the mixture includes 50% or more of the methyl terminus, the mixing ratio alone is a relatively good predictor of adsorption, regardless of the relative chain lengths of the thiols used in the mixture. This trend persists at any mixing ratio for SAMs where methyl- and hydroxyl-terminated groups are the same length or where the hydroxyl-terminated thiol is longer. The only variance observed is at low mixing ratios (<50% methyl-terminated) for a mixed SAM where the methyl-terminated component has a longer chain length. Relative protein adsorption increases on these mixtures, perhaps due to the disordered exposure of the excess alkane backbone. Taken together, however, we do not find significant evidence that varying chain lengths for mixed SAMs prepared on polycrystalline substrates and analyzed in air have an outsized influence on nanoscopic adsorption behavior, despite molecular-level disorder in the SAM itself.


Assuntos
Soroalbumina Bovina , Compostos de Sulfidrila , Adsorção , Compostos de Sulfidrila/química , Propriedades de Superfície
5.
J Fungi (Basel) ; 9(9)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37754996

RESUMO

Candida tropicalis is one of the most pathogenic species within the genus. Increased antifungal resistance has been reported, which is in part due to the organism's ability to form biofilms. In natural products derived from plants, such as essential oils (EOs) or their major components, there is significant potential to develop new antifungals or to both enhance the efficacy and reduce the toxicity of conventional antifungals. This study aimed to evaluate the effect of combining an EO of Lippia origanoides or thymol with fluconazole on an azole-resistant C. tropicalis strain. Synergism was observed in the combination of fluconazole with the EO and with thymol, and minimal inhibitory concentrations for fluconazole decreased at least 32-fold. As a consequence of the synergistic interactions, mitochondrial membrane potential was reduced, and mitochondrial superoxide production increased. Alteration in nuclear morphology, cell surface, and ultrastructure was also observed. In conclusion, the synergistic interaction between L. origanoides EO or thymol with fluconazole reverted the azole-resistant C. tropicalis phenotype. These findings suggest that L. origanoides EO or thymol alone, or in combination with fluconazole, have the potential for development as antifungal therapies for this yeast, including resistant strains.

6.
J Oral Sci ; 65(3): 176-183, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37258231

RESUMO

PURPOSE: The aim of this study was to optimize the immunoresponsive and anti-Candida albicans (C. albicans) properties of guided bone regeneration-resorbable membranes (collagen) using additives based on synergistic mixtures of chlorhexidine with terpene-enriched fractions from Lippia alba essential oils (EO). METHODS: The anti-C. albicans activity of the fractions (individually or combined with chlorhexidine) was evaluated using planktonic and sessile cultures. J774A.1 murine macrophage cells were used to determine the cytotoxicity and immunoresponsive effects of the therapies. RESULTS: The anti-planktonic and anti-sessile performance of chlorhexidine on C. albicans was improved 2- to 4-fold by supplementation with citral-rich fractions. On macrophages, this fraction also exhibited a potentially cytoprotective action against the toxic effects of chlorhexidine, minimizing damage to the cell membrane, mitochondrial membrane potential, and nuclear integrity. Macrophages growing on collagen-membrane fragments and stimulated with the citral fraction (alone or with chlorhexidine) showed a significant increase in releasing the osteogenic cytokine TNF-α and enhancing the IL-4. CONCLUSION: This combined therapy appears as a promising platform for the development of a prophylactic or therapeutic biocidal solution that can optimize the pharmacological characteristics of chlorhexidine (epithelium tolerance and anti-C. albicans consolidation on surfaces), as well as potentiating the immunoresponsive properties of collagen membranes.


Assuntos
Lippia , Óleos Voláteis , Camundongos , Animais , Óleos Voláteis/farmacologia , Clorexidina , Regeneração Óssea
7.
Rev. cuba. reumatol ; 24(4)dic. 2022.
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1530172

RESUMO

El aborto inducido es el resultado de maniobras practicadas con la intención de interrumpir el embarazo. Esta acción puede provocar complicaciones que ponen en riesgo la vida de la mujer, lo que muestra la importancia de los cuidados de enfermería para minimizar el riesgo de complicaciones en el posaborto. El propósito del estudio es describir los cuidados de enfermería a implementar en las mujeres con aborto por automedicación. Se realizó una revisión bibliográfica que incluyó la búsqueda, selección, revisión, interpretación y síntesis de la evidencia científica publicada relacionada con el problema de investigación. Se revisaron documentos publicados en los últimos 5 años en bases de datos regionales y de alto impacto como son Scielo, Redalyc, Latindex y PudMed. Se usaron descriptores de salud relacionados con el tema propuesto en idioma español, inglés y portugués. Se identificó un total de 83 documentos, de los cuales se usaron 46 en la investigación realizada. Los restantes 37 manuscritos fueron excluidos por presentar deficiencias metodológicas que limitaban su uso, o que su eje central no se ajustaba al tema de investigación planteado. Los cuidados de enfermería desempeñan un papel fundamental en la prevención o detección precoz de complicaciones en las mujeres con abortos por automedicación. La prevención de este tipo de actos debe fomentarse antes de la concepción de la gestación, basado en una adecuada educación sexual a las mujeres en edad fértil(AU)


Induced abortion is the result of maneuvers performed with the intention of interrupting pregnancy. This action can generate complications that put the woman's life at risk, which shows the importance of nursing care to minimize the risk of post-abortion complications. To describe the nursing care to be implemented in women with self-medication abortion. A bibliographic review was carried out that included the search, selection, review, interpretation and synthesis of the published scientific evidence related to the research problem. Documents published in the last 5 years in regional and high-impact databases such as Scielo, Redalyc, Latindex and PudMed were used. Health descriptors related to the proposed theme were used in Spanish, English and Portuguese. A total of 83 documents were identified, of which 46 were used in the research carried out. The remaining 37 manuscripts were excluded due to methodological deficiencies that limited their use; or that its central axis did not fit the proposed research topic. Nursing care plays a fundamental role in the prevention or early detection of complications in women with self-medication abortions. The prevention of this type of acts should be encouraged before the conception of pregnancy, based on adequate sexual education for women of childbearing age(AU)


Assuntos
Humanos , Feminino , Gravidez , Automedicação , Aborto Induzido/métodos , Cuidados de Enfermagem , Equador
8.
Viruses ; 14(11)2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-36423193

RESUMO

Animal models are used in preclinical trials to test vaccines, antivirals, monoclonal antibodies, and immunomodulatory drug therapies against SARS-CoV-2. However, these drugs often do not produce equivalent results in human clinical trials. Here, we show how different animal models infected with some of the most clinically relevant SARS-CoV-2 variants, WA1/2020, B.1.617.2/Delta, B.1.1.529/Omicron, and BA5.2/Omicron, have independent outcomes. We show that in K18-hACE2 mice, B.1.617.2 is more pathogenic, followed by WA1, while B.1.1.529 showed an absence of clinical signs. Only B.1.1.529 was able to infect C57BL/6J mice, which lack the human ACE2 receptor. B.1.1.529-infected C57BL/6J mice had different T cell profiles compared to infected K18-hACE2 mice, while viral shedding profiles and viral titers in lungs were similar between the K18-hACE2 and the C57BL/6J mice. These data suggest B.1.1.529 virus adaptation to a new host and shows that asymptomatic carriers can accumulate and shed virus. Next, we show how B.1.617.2, WA1 and BA5.2/Omicron have similar viral replication kinetics, pathogenicity, and viral shedding profiles in hamsters, demonstrating that the increased pathogenicity of B.1.617.2 observed in mice is host-dependent. Overall, these findings suggest that small animal models are useful to parallel human clinical data, but the experimental design places an important role in interpreting the data. Importance: There is a need to investigate SARS-CoV-2 variant phenotypes in different animal models due to the lack of reproducible outcomes when translating experiments to the human population. Our findings highlight the correlation of clinically relevant SARS-CoV-2 variants in animal models with human infections. Experimental design and understanding of correct animal models are essential to interpreting data to develop antivirals, vaccines, and other therapeutic compounds against COVID-19.


Assuntos
COVID-19 , SARS-CoV-2 , Cricetinae , Camundongos , Animais , Humanos , SARS-CoV-2/genética , Camundongos Endogâmicos C57BL , Virulência , Modelos Animais de Doenças , Antivirais
9.
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1451641

RESUMO

Introducción. La distonía es un trastorno del movimiento que produce afectaciones funcionales a quienes la padecen; la aplicación de toxina botulínica es el tratamiento de elección debido a su seguridad. Objetivo. Describir losresultadosclínicos del uso a largo plazo de toxina botulínica en un grupo de pacientes con diagnóstico de distonía atendidos en un hospital de tercer nivel de complejidad de Bogotá, Colombia. Métodos. Estudio observacional. Se revisaron las historiasclínicas de los pacientescon diagnóstico de distonía atendidos en la clínica de espasticidad y distonía de una institución de salud. El dolorse evaluó con la escala visual análoga (EVA)yla percepción de mejoría de síntomas(recuperación de los arcos de movilidad y disminución de movimientos involuntarios); además, el especialista que realizó la aplicación de la toxina botulínica analizó el comportamiento de estas variables en el tiempo. Resultados. Se incluyeron 28 pacientes, el tipo de distonía más frecuente fue la cervical (75%) y el promedio de tiempo de tratamiento fue de 4,95 años (DE=2,89). Se encontró una reducción de dolor del 79,32%, la cual se mantuvo en el tiempo (p<0,05); además, la percepción de síntomas por parte del paciente tuvo una mejoría del 83,75% (p<0,05) y la apreciación de resultados por parte del fisiatra fue del 88,39% (p=0,157). Conclusiones. La toxina botulínica en el manejo de la distonía en la población de estudio mostró ser un tratamiento seguro y eficaz, esto posterior a varios ciclos de aplicación.


Introduction. Dystonia is a movement disorder that causes functional impairment to those who suffer from it; the application of botulinum toxin is the treatment of choice due to its safety. Objective. To describe the clinical results of the long-term use of botulinum toxin in a group of patients with a diagnosis of dystonia treated in a third level hospital in Bogota, Colombia. Methods. Observational study. The clinical histories of patients with a diagnosis of dystonia attended at the spasticity and dystonia clinic of a health institution were reviewed. Pain was evaluated with the visual analog scale (VAS) and the perception of symptom improvement (recovery of mobility arcs and reduction of involuntary movements); in addition, the specialist who performed the application of botulinum toxin analyzed the behavior of these variables over time. Results. Twenty-eight patients were included, the most frequent type of dystonia was cervical (75%) and the average treatment time was 4.95 years (SD=2.89). A pain reduction of 79.32% was found, which was maintained over time (p<0.05); in addition, the perception of symptoms by the patient had an improvement of 83.75% (p<0.05) and the appreciation of results by the physiatrist was 88.39% (p=0.157).


Assuntos
Humanos , Feminino , Gravidez , Pessoa de Meia-Idade
10.
Dermatol Res Pract ; 2021: 5539149, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34394343

RESUMO

BACKGROUND: Skin cancer is one of the most common cancers, and melanoma is a highly preventable cancer. In Ecuador, few studies have evaluated the awareness levels of the population about the disease. For this reason, the objective of this study was to measure the level of knowledge, attitudes, and practices regarding skin cancer and its determining factors. METHODS: A cross-sectional analysis using an online self-assessment questionnaire containing 40 questions was delivered. A total of 537 participants were included in this study. Knowledge, attitude, and practice scores were assigned to each participant based on the number of correct or appropriate responses. Logistic regression analysis was used to calculate crude and adjusted odds ratios. RESULTS: In total, 75% of participants referenced knowledge of the harmful effects related to noncontrolled solar exposure. Concerning sunscreen, 76.7% knew the reason for using it. The female group was 1.68 times more likely to get a higher score than the male group, and the groups between 61-70 and 71-80 years were 0.30 and 0.17 times less likely to get a higher score compared with the less than 20-years-old group, respectively. CONCLUSIONS: The findings of this study indicate the requirement to increase the population's knowledge about skin cancer and possible protection measures. For this reason, the prevention and health promotion programs at a national level from primary healthcare centers are recommended. Due to the limitation of the representativeness of the sample, the use of more studies among Ecuadorian residents of the low socioeconomic level and replication in different provinces of Ecuador is justified.

11.
BMC Complement Med Ther ; 21(1): 187, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215249

RESUMO

BACKGROUND: Parasite persistence, exacerbated and sustained immune response, and continuous oxidative stress have been described to contribute to the development of the cardiac manifestations in Chronic Chagas Disease. Nevertheless, there are no efficient therapies to resolve the Trypanosoma cruzi infection and prevent the disease progression. Interestingly, trypanocide, antioxidant, and immunodulatory properties have been reported separately for some major terpenes, as citral (neral plus geranial), limonene, and caryophyllene oxide, presents in essential oils (EO) extracted from two chemotypes (Citral and Carvone) of Lippia alba. The aim of this study was to obtain L. alba essential oil fractions enriched with the aforementioned bioactive terpenes and to evaluate the impact of these therapies on trypanocide, oxidative stress, mitochondrial bioenergetics, genotoxicity, and inflammatory markers on T. cruzi-infected macrophages. METHODS: T. cruzi-infected J774A.1 macrophage were treated with limonene-enriched (ACT1) and citral/caryophyllene oxide-enriched (ACT2) essential oils fractions derived from Carvone and Citral-L. alba chemotypes, respectively. RESULTS: ACT1 (IC50 = 45 ± 1.7 µg/mL) and ACT2 (IC50 = 80 ± 1.9 µg/mL) exhibit similar trypanocidal effects to Benznidazole (BZN) (IC50 = 48 ± 2.5 µg/mL), against amastigotes. Synergistic antiparasitic activity was observed when ACT1 was combined with BZN (∑FIC = 0.52 ± 0.13 µg/mL) or ACT2 (∑FIC = 0.46 ± 1.7 µg/mL). ACT1 also decreased the oxidative stress, mitochondrial metabolism, and genotoxicity of the therapies. The ACT1 + ACT2 and ACT1 + BZN experimental treatments reduced the pro-inflammatory cytokines (IFN-γ, IL-2, and TNF-α) and increased the anti-inflammatory cytokines (IL-4 and IL-10). CONCLUSION: Due to its highly trypanocidal and immunomodulatory properties, ACT1 (whether alone or in combination with BZN or ACT2) represents a promising L. alba essential oil fraction for further studies in drug development towards the Chagas disease control.


Assuntos
Antioxidantes/farmacologia , Lippia , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Tripanossomicidas/farmacologia , Animais , Linhagem Celular , Células Cultivadas , Citocinas/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Nitroimidazóis/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Trypanosoma cruzi/citologia , Trypanosoma cruzi/efeitos dos fármacos
12.
Proc Natl Acad Sci U S A ; 118(29)2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34193524

RESUMO

Successfully combating the COVID-19 pandemic depends on mass vaccination with suitable vaccines to achieve herd immunity. Here, we describe COVI-VAC, the only live attenuated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine currently in clinical development. COVI-VAC was developed by recoding a segment of the viral spike protein with synonymous suboptimal codon pairs (codon-pair deoptimization), thereby introducing 283 silent (point) mutations. In addition, the furin cleavage site within the spike protein was deleted from the viral genome for added safety of the vaccine strain. Except for the furin cleavage site deletion, the COVI-VAC and parental SARS-CoV-2 amino acid sequences are identical, ensuring that all viral proteins can engage with the host immune system of vaccine recipients. COVI-VAC was temperature sensitive in vitro yet grew robustly (>107 plaque forming units/mL) at the permissive temperature. Tissue viral loads were consistently lower, lung pathology milder, and weight loss reduced in Syrian golden hamsters (Mesocricetus auratus) vaccinated intranasally with COVI-VAC compared to those inoculated with wild-type (WT) virus. COVI-VAC inoculation generated spike IgG antibody levels and plaque reduction neutralization titers similar to those in hamsters inoculated with WT virus. Upon challenge with WT virus, COVI-VAC vaccination reduced lung challenge viral titers, resulted in undetectable virus in the brain, and protected hamsters from almost all SARS-CoV-2-associated weight loss. Highly attenuated COVI-VAC is protective at a single intranasal dose in a relevant in vivo model. This, coupled with its large-scale manufacturing potential, supports its potential use in mass vaccination programs.


Assuntos
Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/farmacologia , COVID-19/imunologia , COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Animais , Anticorpos Antivirais/imunologia , COVID-19/epidemiologia , Chlorocebus aethiops , Feminino , Humanos , Masculino , Mesocricetus , Pandemias , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinação , Vacinas Atenuadas/imunologia , Células Vero
13.
Biomédica (Bogotá) ; 41(supl.1): 47-59, mayo 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1285449

RESUMO

Abstract | Introduction: Chagas' disease is the leading cause of infectious myocarditis worldwide. This infection caused by Trypanosoma cruzi is usually life-long and asymptomatic; however, the third part of infected people can develop severe or even fatal cardiomyopathy. As the parasitemia in the chronic phase is both low-grade and intermittent, T. cruzi infection is principally detected by serology, although this method has sensitivity and specificity limitations. Objective: To determine the level of agreement between serologicand molecular tests in 658 voluntary blood donors from six provinces in the Colombian department of Santander. Materials and methods: We evaluated an array of diagnostic technologies by cross-section sampling performing a serological double diagnostic test for T. cruzi antibody detection (Chagas III ELISA™, BiosChile Group, and ARCHITECT Chagas CMIA™, Abbott) , and DNA detection by polymerase chain reaction (PCR). We collected the demographic, clinical, and epidemiological information of participants. The sample size was calculated using Epidat™ and the statistical analysis was done with Stata 12.1™. Results: PCR was six times more sensitive in detecting T. cruzi infection than ELISA/CMIA with prevalence values of 1.8% (12/658) and 0.3% (2/658), respectively, and kappa=0.28 (95%CI: -0.03 - 0.59). In contrast, serology showed a sensitivity of 16.7% (95%CI: 2.09 - 48.4) and a specificity of 100% (95%CI: 99.4 - 100). All seropositive samples were found to be positive by PCR. Conclusions: The implementation of PCR as a complementary method for screening donors could reduce the probability of false negative and the consequent risk of transfusional-transmission of Chagas' disease, especially in endemic regions.


Resumen | Introducción. La enfermedad de Chagas constituye la principal causa de miocarditis infecciosa en el mundo. Causada por Trypanosoma cruzi,la infección puede persistir toda la vida de manera asintomática y silenciosa, pero un tercio de los infectados desarrolla cardiomiopatía grave. Debido a que la parasitemia en la fase crónica es baja e intermitente, el diagnóstico se hace principalmente mediante la detección de anticuerpos (serología), método que tiene limitaciones de sensibilidad y especificidad. Objetivo. Determinar la concordancia entre el diagnóstico serológico y molecular de T. cruzien 658 donantes voluntarios de sangre del departamento de Santander, Colombia. Materiales y métodos. Se hizo un estudio de evaluación de tecnologías diagnósticas con muestreo transversal, utilizando un doble diagnóstico serológico para la detección de anticuerpos anti-T. cruzi (Chagas III ELISA™, BiosChile Group, y ARCHITECT ChagasCMIA™, Abbott) y la de ADN por PCR. Se recolectó la información demográfica, clínica y epidemiológica de los participantes. El tamaño de la muestra se estimó utilizando Epidat™ y el análisis estadístico se hizo mediante Stata 12.1™. Resultados. La sensibilidad de la PCR fue seis veces mayor que la de las pruebas de ELISA/CMIA, con prevalencias de 1,8 % (12/658) y 0,3 % (2/658), respectivamente, y kappa de 0,28 (IC95% -0,03 - 0,59). La sensibilidad serológica fue de 16,7 % (IC95% 2,09 - 48,4) y la especificidad de 100 % (IC95% 99,4 - 100). Todas las muestras seropositivas fueron positivas también en la PCR. Conclusiones. El uso de la PCR como método complementario para la tamización de donantes podría reducir el riesgo de falsos negativos y disminuir los casos de transmisión transfusional de la enfermedad de Chagas, especialmente en regiones endémicas.


Assuntos
Trypanosoma cruzi , Doadores de Sangue , Sorologia , Reação em Cadeia da Polimerase , Doença de Chagas
14.
Brain Sci ; 11(1)2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33401410

RESUMO

Studies so far have analyzed the effect of distractor stimuli in different types of brain-computer interface (BCI). However, the effect of a background speech has not been studied using an auditory event-related potential (ERP-BCI), a convenient option when the visual path cannot be adopted by users. Thus, the aim of the present work is to examine the impact of a background speech on selection performance and user workload in auditory BCI systems. Eleven participants tested three conditions: (i) auditory BCI control condition, (ii) auditory BCI with a background speech to ignore (non-attentional condition), and (iii) auditory BCI while the user has to pay attention to the background speech (attentional condition). The results demonstrated that, despite no significant differences in performance, shared attention to auditory BCI and background speech required a higher cognitive workload. In addition, the P300 target stimuli in the non-attentional condition were significantly higher than those in the attentional condition for several channels. The non-attentional condition was the only condition that showed significant differences in the amplitude of the P300 between target and non-target stimuli. The present study indicates that background speech, especially when it is attended to, is an important interference that should be avoided while using an auditory BCI.

16.
Sci Total Environ ; 753: 141843, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32906040

RESUMO

Determining the resistance and resilience of resources and benthic invertebrates connected to instream refuges and species re-colonization in post-flood periods may help to elucidate mechanisms behind community recovery. This experiment simulated flow pulses in a small temporary stream in an extremely wet year, using upstream control and downstream flooded reaches at three sites in order to assess community resistance and resilience (benthos and drift), and analyse resources (periphyton and benthic organic matter) and invertebrates at pre- and post-flood time periods. The hyporheos was sampled in order to explore species exchanges with benthos. Fewer resources and benthic invertebrates at the beginning of the experiment were found than in previous studies when base flow conditions prevailed. Resource stocks and benthic invertebrates showed high resistance to the flow pulse. Interestingly, there was low resilience of benthic organic matter to natural seasonal flooding. Chlorophyll a did not recover after experimental floods; instead, it was reduced after floods, despite the more benign flow conditions and non-limiting irradiance levels, pointing to top-down control by consumers. Additionally, the experimental flood significantly disturbed only the invertebrate composition in the groundwater-fed stream, which was inhabited by the fewest adapted-to-flood-disturbances macroinvertebrates. Despite the low resilience observed, richness and densities of benthos increased during the study, evidencing progressive colonization. Around 50-60% of macroinvertebrates were present in both benthos and hyporheos. Richness increased after flooding, suggesting that the hyporheic zone could be the main source of colonizers. Three species traits characterized the hyporheos: small size, cocoons and feeders of microorganisms within the fine sediment matrix. The main results indicate that longer-than-normal flood periods in early spring may constrain invertebrate succession before the next summer drought in temporary streams. This study underscores the importance of hyporheic fauna as a significance source of colonizers, highlighting the importance of connectivity to the groundwater.

17.
Rev. MED ; 28(2): 71-84, jul.-dic. 2020. tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1406908

RESUMO

Resumen: La enfermedad por coronavirus 2019 (COVID-19) causada por el virus SARS-CoV-2 es una nueva enfermedad caracterizada por generar daño pulmonar y compromiso de múltiples tejidos y órganos de todo el cuerpo. Algunos de los pacientes que presentan la infección ameritan manejo intrahospitalario con soporte de O2 y medidas adicionales que pueden incluir inmovilización prolongada en UCI. Los pacientes que presentan cuadros moderados o severos y sobreviven a la enfermedad pueden presentar deterioro y disfunciones a largo plazo, incluyendo fibrosis pulmonar, miocardiopatía, lesión renal, hepática, de nervio periférico y todas las complicaciones derivadas de hospitalizaciones en UCI. Se considera que la intervención en rehabilitación pulmonar reviste gran importancia, especialmente en la etapa de recuperación, y debe realizarse, principalmente, con los objetivos de mejorar la disnea, la debilidad muscular severa y la fatiga, a fin de promover la independencia funcional y aumentar la calidad de vida, de manera que se disminuye así la ansiedad y la depresión.


Abstract: Coronavirus disease 2019 (COVID-19) caused by SARS-COV-2 virus is a new disease characterized by generating lung damage and compromising multiple tissues and organs throughout the body. Some of the patients with the infection should need intrahospital management with O2 support and additional measures that may include prolonged ICU immobilization. Patients who have moderate or severe conditions and survive the disease, could experience long-term impairment and dysfunction, including pulmonary fibrosis, cardiomyopathy, renal, hepatic and peripheral nerve injury, and all complications arising from hospitalizations in the ICU. It is considered that intervention in pulmonary rehabilitation is particularly important, especially at the recovery stage, and should be performed mainly with the objectives of improving: dyspnea, severe muscle weakness and fatigue, in order to promote functional independence and increase quality of life, so that anxiety and depression are diminished.


Resumo: A doença por coronavírus (COVID-19), causada pelo vírus SARS-COV-2, é uma nova doença caracterizada por gerar dano pulmonar e comprometimento de múltiplos tecidos e órgãos de todo o corpo. Alguns dos pacientes que apresentam a infecção merecem atendimento intra-hospitalar com suporte de O2 e medidas extraordinárias que podem incluir imobilização prolongada na UTI. Os pacientes que apresentam quadros moderados ou graves e sobrevivem à doença podem apresentar deterioração e disfunções em longo prazo, incluindo fibrose pulmonar, miocardiopatia, lesão renal, hepática, de nervo periférico e todas as complicações derivadas de internações em UTI. Considera-se que a intervenção em reabilitação pulmonar ganha grande importância, especialmente na etapa de recuperação, e deve realizar-se principalmente com o objetivo de melhorar a dispneia, a debilidade muscular grave e a fatiga, a fim de promover a independência funcional e aumentar a qualidade de vida, para que assim a ansiedade e a depressão diminuam.

18.
Mar Pollut Bull ; 157: 111323, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32658688

RESUMO

The Albuquerque atoll was studied as a representative natural laboratory to explore the role of sea-based sources of marine litter. This work aimed to identify the small-scale spatial distribution of marine litter (i.e., plastic, glass, paper, and others) as well as to explore the connectivity among the atoll habitats (sand beach, water surface, and reef) to give insights of potential sources of marine litter (>5 cm), mainly plastics. Marine litter was dominated by plastic items, as expected, with an average value of 0.5 items/m2. Large microplastics (1-5 mm) were also sampled on beaches with an average value of 90 particles/m2. In the atoll inner lagoon, marine litter was also composed by plastic, mainly fragments (average 0.059 items/m3). The predominance of plastic fragments on both the sea surface and beaches of the atoll makes inferences on sources limited. However, o fishing activities and sea-based sources might be relevant since local sources are very limited.


Assuntos
Praias , Plásticos , Região do Caribe , Monitoramento Ambiental , Resíduos/análise
19.
Toxicol Lett ; 330: 59-64, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32437847

RESUMO

Gene-specific methylation has been related with transcriptional/translational consequences in different cells; also, this epigenetic modification is affected by environmental exposures. In previous studies, CYP2E1 activity in toluene-exposed workers was decreased compared to controls, however, CYP2E1 promoter methylation levels did not show significant differences. Here, we compared gene-specific methylation levels at the 5'UTR region, in a subset of workers whom already participated in two former studies, compared to controls. METHODS: DNA was obtained from whole blood in five different groups: occupationally exposed to a mixture of volatile organic compounds (VOC): high levels (n = 19); low levels (n = 19) and very low levels (n = 17), toluene-exposed workers (n = 19) and control group (n = 19). We performed PCR-pyrosequencing at the 5'UTR region from four genes: CYP2E1, IL-6, SOD1 and TNF-α. RESULTS: In participants exposed to high levels of a VOC mixture, we found significant differences: lower methylation levels for IL-6, and higher methylation levels for TNF-α compared to controls. In toluene-exposed workers, we found significant, lower methylation levels for CYP2E1 compared to controls. CONCLUSION: Lower methylation levels at the 5'UTR region from CYP2E1 in toluene exposed-workers, suggests that this epigenetic modification could represent a functional correlate regarding enzymatic activity, as a response to toluene biotransformation.

20.
Toxicol Lett ; 330: 73-79, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32439582

RESUMO

Human exposure to n-hexane has been associated with subfertility and, experimentally, with a decrease in follicular development. In order to assess occupational exposure to n-hexane on ovarian function and gonadotropic hormones, we studied Mexican women labouring in a leather shoe factory (n = 34). Individual environmental levels for seven solvents, n-hexane included, were measured; also, urinary 2,5-hexanedione (2,5-HD) was determined. For ovarian function and hormonal status, FSH, LH, oestradiol and anti-Müllerian hormone (AMH) levels were determined. We performed all determinations also in a reference group, administrative workers with no exposure to solvents (n = 32). Results: N-hexane and urinary 2,5-HD levels were higher in exposed group (p < 0.001). More cases of oligomenorrhea as well as longer time for getting pregnant were observed in exposed women compared with controls; a positive association was found between menstrual cycle length and "time for getting pregnant" (p = 0.010); significant associations between FSH serum levels and 2,5-HD urinary levels (post-shift sample) were observed in non-smokers participants presenting oligomenorrhea from exposed group. Also, we found a trend for lower oestradiol levels in exposed participants with current smoking habit (p = 0.059). Conclusions: 2,5-HD urinary levels are associated with decreased gonadotropins levels; hence, n-hexane should be considered an endocrine disruptor in reproductive-age women.

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