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1.
PLoS Negl Trop Dis ; 16(1): e0010109, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35030166

RESUMO

BACKGROUND: Neurocysticercosis (NCC), and cystic echinococcosis (CE) are two neglected diseases caused by cestodes, co-endemic in many areas of the world. Imaging studies and serological tests are used in the diagnosis of both parasitic diseases, but cross-reactions may confound the results of the latter. The novel multiplex bead-based assay with recombinant antigens has been reported to increases the diagnostic accuracy of serological techniques. METHODOLOGY: We set-up an immunoassay based on the multiplex bead-based platform (MBA), using the rT24H (against Cysticercus cellulosae, causing cysticercosis) and r2B2t (against Echinococcus granulosus sensu lato, causing CE) recombinant antigens, for simultaneous and differential diagnosis of these infections. The antigens were tested on 356 sera from 151 patients with CE, 126 patients with NCC, and 79 individuals negative for both diseases. Specificity was calculated including sera from healthy donors, other neurological diseases and the respective NCC or CE sera counterpart. The diagnostic accuracy of this assay was compared with two commercial ELISA tests, Novalisa and Ridascreen, widely used in the routine diagnosis of cysticercosis and CE, respectively. MAIN FINDINGS: For the diagnosis of NCC, sensitivity ranged from 57.94-63.49% for the rT24H-MBA, and 40.48-46.03% for Novalisa ELISA depending on exclusion or inclusion of sera having equivocal results on ELISA from the analysis; specificities ranged from 90.87-91.30% and 70.43-76.96%, respectively. AUC values of the ROC curve were 0.783 (rT24H) and 0.619 (Novalisa) (p-value < 0.001). For the diagnosis of CE, the sensitivity of the r2B2t-MBA ranged from 68.87-69.77% and of Ridascreen ELISA from 50.00-57.62%; specificities from 92.47-92.68% and from 74.15-80.98%, respectively. AUC values were 0.717 and 0.760, respectively. CONCLUSIONS/SIGNIFICANCE: Overall, the recombinant antigens tested with the bead-based technology showed better diagnostic accuracy than the commercial assays, particularly for the diagnosis of NCC. The possibility of testing the same serum sample simultaneously for the presence of antibodies against both antigens is an added value particularly in seroprevalence studies for cysticercosis linked to control programs in endemic areas where these two parasites coexist.


Assuntos
Anticorpos Anti-Helmínticos/sangue , Equinococose/diagnóstico , Echinococcus granulosus/imunologia , Neurocisticercose/diagnóstico , Taenia solium/imunologia , Animais , Antígenos de Helmintos/genética , Antígenos de Helmintos/imunologia , Equinococose/parasitologia , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Doenças Negligenciadas/diagnóstico , Doenças Negligenciadas/parasitologia , Neurocisticercose/parasitologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade , Testes Sorológicos
2.
Inorg Chem ; 60(6): 4162-4170, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33662207

RESUMO

Neutral arenes such as benzene have never been considered suitable ligands for electropositive actinide cations, yet we find that even simple UIII UX3 aryloxide complexes such as U(ODipp)3 bind and reduce arenes spontaneously at room temperature, forming inverse arene sandwich (IAS) complexes XnU(µ-C6D6)UXm (X = ODipp, n=2, m=3; X = OBMes2 n=m=2 or 3) (ODipp = OC6H3iPr2-2,6; Mes = 2,4,6-Me3-C6H2). In some of these cases, further arene reduction has occured as a result of X ligand redistribution. These unexpected spontaneous reactions explain the anomalous spectra and reported lack of further reactivity of strongly reducing UIII centers of U(ODipp)3. Phosphines that are not considered suitable ligands for actinides can catalyze the formation of the IAS complexes. This enables otherwise inaccessible asymmetric and less congested IAS complexes to be isolated and the bonding in this series compared.

3.
Cells ; 9(5)2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32438605

RESUMO

Reelin is an extracellular glycoprotein that modulates neuronal function and synaptic plasticity in the adult brain. Decreased levels of Reelin activity have been postulated as a key factor during neurodegeneration in Alzheimer´s disease (AD) and in aging. Thus, changes in levels of full-length Reelin and Reelin fragments have been revealed in cerebrospinal fluid (CSF) and in post-mortem brains samples of AD patients with respect to non-AD patients. However, conflicting studies have reported decreased or unchanged levels of full-length Reelin in AD patients compared to control (nND) cases in post-mortem brains and CSF samples. In addition, a compelling analysis of Reelin levels in neurodegenerative diseases other than AD is missing. In this study, we analyzed brain levels of RELN mRNA and Reelin protein in post-mortem frontal cortex samples from different sporadic AD stages, Parkinson's disease with dementia (PDD), and Creutzfeldt-Jakob disease (sCJD), obtained from five different Biobanks. In addition, we measured Reelin protein levels in CSF samples of patients with mild cognitive impairment (MCI), dementia, or sCJD diagnosis and a group of neurologically healthy cases. The results indicate an increase in RELN mRNA in the frontal cortex of advanced stages of AD and in sCJD(I) compared to controls. This was not observed in PDD and early AD stages. However, Reelin protein levels in frontal cortex samples were unchanged between nND and advanced AD stages and PDD. Nevertheless, they decreased in the CSF of patients with dementia in comparison to those not suffering with dementia and patients with MCI. With respect to sCJD, there was a tendency to increase in brain samples in comparison to nND and to decrease in the CSF with respect to nND. In conclusion, Reelin levels in CSF cannot be considered as a diagnostic biomarker for AD or PDD. However, we feel that the CSF Reelin changes observed between MCI, patients with dementia, and sCJD might be helpful in generating a biomarker signature in prodromal studies of unidentified dementia and sCJD.


Assuntos
Moléculas de Adesão Celular Neuronais/genética , Proteínas da Matriz Extracelular/genética , Proteínas do Tecido Nervoso/genética , Doenças Neurodegenerativas/genética , Serina Endopeptidases/genética , Encéfalo/metabolismo , Encéfalo/patologia , Moléculas de Adesão Celular Neuronais/líquido cefalorraquidiano , Moléculas de Adesão Celular Neuronais/metabolismo , Proteínas da Matriz Extracelular/líquido cefalorraquidiano , Proteínas da Matriz Extracelular/metabolismo , Humanos , Proteínas do Tecido Nervoso/líquido cefalorraquidiano , Proteínas do Tecido Nervoso/metabolismo , Doenças Neurodegenerativas/líquido cefalorraquidiano , Doenças Neurodegenerativas/patologia , Mudanças Depois da Morte , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteína Reelina , Serina Endopeptidases/líquido cefalorraquidiano , Serina Endopeptidases/metabolismo
4.
Saúde Soc ; 28(3): 224-238, jul.-set. 2019. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1043380

RESUMO

Resumen Los padres buscan apoyo para enfrentar los desafíos que sus hijos tienen en la adolescencia. El objetivo de este trabajo es analizar los tópicos abordados en la formación de padres con hijos adolescentes y su relación con las tendencias comportamentales de estos. Para ello, se llevó a cabo una revisión cualitativa de intervenciones y programas centrados en fortalecer el proceso de crianza, estableciéndose una concentración en los aspectos regulatorios, comunicativos y emocionales de la relación padre-hijo. Por medio de un análisis cuantitativo, también se pudo establecer que los tópicos abordados tienen efectos significativos sobre los adolescentes, como la reducción en problemas de comportamiento, manejo adecuado de la sexualidad y disminución en la tendencia al consumo de sustancias. Teniendo en cuenta la información registrada, es posible plantear que la formación parental puede abordarse en diferentes formatos de acuerdo con los objetivos y condiciones disponibles, lo que puede representar beneficios importantes para el desarrollo saludable de los adolescentes.


Abstract Parents seek support to cope with the challenges their adolescents face. The objective of this paper is to analyze the topics addressed in the training of parents and their relation with adolescent behavioral tendencies. A qualitative review of interventions and programs focused on strengthening the parenting process was carried out, establishing a concentration on the regulatory, communicative and emotional aspects of the parent-child relationship. Through a quantitative analysis, it was also identified that the topics addressed have significant effects on adolescents, such as the reduction of behavioral problems, adequate management of sexuality and a decrease in the tendency to use substances. With this considered, it is possible to state that parental training can be addressed in different formats according to the objectives and conditions available, which can represent important benefits for the healthy development of adolescents.


Assuntos
Relações Pais-Filho , Comportamento do Adolescente , Poder Familiar , Sexualidade , Revisão
5.
Dalton Trans ; 48(15): 4894-4905, 2019 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-30924481

RESUMO

The boroxide ligand [OBAr2]- (Ar = Mes, Trip) is shown to be able to support both UIII and UIV centres for the first time. The synthesis and structures of homoleptic and heteroleptic UIII and UIV complexes are reported. The UX3 complex with larger substituents, [U(OBTrip2)3]2, exhibits greater thermal stability compared to less encumbered [U(OBMes2)3]2 but reacts with a smaller range of the small molecules tested to date. Initial studies on their capacity to participate in small molecule chemistry show that dark purple [U(OBMes2)3]2 binds and/or reductively activates a variety of small molecules such as pyridine-oxide, triphenylphosphineoxide, sulfur, and dicyclohexylcarbodiimide. While [U(OBMes2)3]2 shows no reaction with CO or CO2, [U(OBTrip2)3]2 is oxidised by both, in the former case forming [U(OBTrip2)4], and in the latter case forming a small quantity of the structurally characterised µ-carbonate product [(µ-CO3){U(OBTrip2)3}2].

7.
Mol Neurobiol ; 55(3): 1847-1860, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28229331

RESUMO

The cellular prion protein, encoded by the gene Prnp, has been reported to be a receptor of ß-amyloid. Their interaction is mandatory for neurotoxic effects of ß-amyloid oligomers. In this study, we aimed to explore whether the cellular prion protein participates in the spreading of α-synuclein. Results demonstrate that Prnp expression is not mandatory for α-synuclein spreading. However, although the pathological spreading of α-synuclein can take place in the absence of Prnp, α-synuclein expanded faster in PrPC-overexpressing mice. In addition, α-synuclein binds strongly on PrPC-expressing cells, suggesting a role in modulating the effect of α-synuclein fibrils.


Assuntos
Neurônios/metabolismo , Proteínas PrPC/genética , Proteínas PrPC/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Animais , Células Cultivadas , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Priônicas/genética , Proteínas Priônicas/metabolismo , Transporte Proteico/fisiologia
8.
Prion ; 11(4): 226-233, 2017 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-28759332

RESUMO

The term 'prion-like' is used to define some misfolded protein species that propagate intercellularly, triggering protein aggregation in recipient cells. For cell binding, both direct plasma membrane interaction and membrane receptors have been described for particular amyloids. In this respect, emerging evidence demonstrates that several ß-sheet enriched proteins can bind to the cellular prion protein (PrPC). Among other interactions, the physiological relevance of the binding between ß-amyloid and PrPC has been a relevant focus of numerous studies. At the molecular level, published data point to the second charged cluster domain of the PrPC molecule as the relevant binding domain of the ß-amyloid/PrPC interaction. In addition to ß-amyloid, participation of PrPC in binding α-synuclein, responsible for neurodegenerative synucleopathies, has been reported. Although results indicate relevant participation of PrPC in the spreading of α-synuclein in living mice, the physiological relevance of the interaction remains elusive. In this comment, we focus our attention on summarizing current knowledge of PrPC as a receptor for amyloid proteins and its physiological significance, with particular focus on α-synuclein.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Doenças Neurodegenerativas/metabolismo , Proteínas PrPC/metabolismo , Células Receptoras Sensoriais/metabolismo , alfa-Sinucleína/metabolismo , Animais , Camundongos
9.
Mol Neurobiol ; 54(8): 6412-6425, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27726110

RESUMO

Reelin is an extracellular glycoprotein involved in key cellular processes in developing and adult nervous system, including regulation of neuronal migration, synapse formation, and plasticity. Most of these roles are mediated by the intracellular phosphorylation of disabled-1 (Dab1), an intracellular adaptor molecule, in turn mediated by binding Reelin to its receptors. Altered expression and glycosylation patterns of Reelin in cerebrospinal and cortical extracts have been reported in Alzheimer's disease. However, putative changes in Reelin are not described in natural prionopathies or experimental models of prion infection or toxicity. With this is mind, in the present study, we determined that Reelin protein and mRNA levels increased in CJD human samples and in mouse models of human prion disease in contrast to murine models of prion infection. However, changes in Reelin expression appeared only at late terminal stages of the disease, which prevent their use as an efficient diagnostic biomarker. In addition, increased Reelin in CJD and in in vitro models does not correlate with Dab1 phosphorylation, indicating failure in its intracellular signaling. Overall, these findings widen our understanding of the putative changes of Reelin in neurodegeneration.


Assuntos
Moléculas de Adesão Celular Neuronais/metabolismo , Síndrome de Creutzfeldt-Jakob/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Doenças Priônicas/metabolismo , Serina Endopeptidases/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Encéfalo/metabolismo , Síndrome de Creutzfeldt-Jakob/genética , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/genética , Neurônios/metabolismo , Fosforilação , Doenças Priônicas/genética , Proteína Reelina
10.
Acta biol. colomb ; 19(2): 155-166, mayo-ago. 2014. ilus, graf, mapas, tab
Artigo em Espanhol | LILACS | ID: lil-715196

RESUMO

Compilamos y analizamos los datos de observaciones realizadas entre los años 2001 y 2013 en tres sectores a lo largo del cauce del río La Vieja, ubicado en el valle geográfico del río Cauca, Colombia. Describimos los datos espacial y temporalmente, enfocándonos en identificar patrones de composición y abundancia de especies. Registramos 28 especies de aves acuáticas en 33 transectos, siendo 22 especies observadas en más del 50 % de los transectos. Las diferencias en el número de especies por transecto no fueron significativas entre los tres sectores del río. Sin embargo, dos análisis de agrupamiento, considerando tanto los datos de presencia/ausencia como de abundancia, indicaron que la composición de especies presenta estructura espacial a lo largo del río. En contraste, aunque las observaciones se realizaron durante más de diez años no se encontró evidencia de cambios temporales en la composición de especies. No obstante, algunas especies mostraron tendencias de aumento o disminución en su frecuencia. Presentamos el nuevo registro de una especie (Chloroceryle aenea) para la región. A pesar de que el paisaje asociado al río La Vieja ha sufrido un gran impacto antropogénico, aún conserva una diversidad significativa de aves acuáticas que pueden servir para aportar valor a los planes de conservación en la zona.


We compiled and analyzed data gathered from observations during the period 2001-2013 in three sectors along La Vieja river, located in the Cauca river valley, Colombia. We describe spatial and temporal aspects of such dataset, focusing in indentify patterns of species' composition and abundance. We recorded 28 waterbird species in 33 transects, being 22 species observed in more than 50 % of these transects. The species richness among transects did not shows significant differences. However, two cluster analyses, considering both presence/absence and abundance data, showed that there is spatial structure in the species composition along the river. In contrast, although observations were conducted during more than ten years there is no evidence of temporal changes in species composition. Still, some species showed increase or decrease trends in their frequency. We present a new record for one species (Chloroceryle aenea) for the region. Despite that the landscape surrounding La Vieja river have faced a high anthropogenic impact, the river still presents a significant diversity of waterbirds, which could add value to the conservation plans in the zone.

11.
Ces med. vet. zootec ; 8(2): 61-72, jul.-dic. 2013. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-703311

RESUMO

Resumen En Colombia son escasas las técnicas de diagnóstico implementadas con biomarcadores inmunohistoquímicos para realizar biomonitoreo de contaminación ambiental. Objetivo: Implementar una técnica inmunohistoquímica para inmunolocalizar CYP 1A en tejidos de peces, luego de realizar un experimento de exposición subaguda al Clorpirifos en tilapias juveniles machos. Métodos: el experimento de dosis subletal, se realizó en un sistema semiestático, con recambio diario del 50% del volumen de agua manteniendo la concentración correspondiente en cada grupo experimental mediante la adición de la mitad de la dosis hasta el día 28. Las concentraciones de Clorpirifos para la exposición fueron 4, 8, y 12 μg/L, en los grupos tratados y 0,0 μg/L en el grupo control. Se tomaron muestras para estudio histopatológico e inmunohistoquímico. Resultados: se encontró diferencia significativa (p<0,05) para algunas lesiones en el hígado, confirmando que este es un órgano de impacto de los efectos del Clorpirifos a bajas dosis. Se verificó la inducción de CYP 1A en el hepatocitos, endotelio y células biliares tanto de los animales expuestos como en los no expuestos. Desde el punto de vista multidimensional no se encontró diferencia estadística entre los tratamientos para las variables estudiadas. Conclusión: se implementó y normalizó una técnica de inmunohistoquímica para la inmunolocalización tisular de CYP 1A, que podrá utilizarse en futuras investigaciones para realizar biomonitoreo de contaminación en las cuencas hidrográficas de Colombia.


Abstract In Colombia the diagnostic techniques for implementing immunohistochemical biomarkers to fulfill biomonitoring of environmental contamination are limited. Objective: To implement an immunohistochemical technique to immunolocate CYP 1A in the tissue of fish, performing a subacute exposition experiment of Clofopirifos in the liver of young male tilapia. Methods: the sublethal dosage was carried out in semi-static state, with a daily refill of 50% of the water volume, maintaining the corresponding concentration in each group through the addition of half of the dosage until the 28th day. The Cloropirifos concentrations for the exposition were 4, 8, and 12 μg/L in the treated groups and 0.0 μg/L in the control group. Samples were taken for histopathological and immunohistochemical study. Results: A significant difference (p<0.05) for some liver lesions, confirming that it is an organ affected by low dosages of Cloropirifos. It verified that the induction of CYP 1A in hepatocyte, endothelium and biliary cells equally in exposed animals and those that weren't exposed. From a multidimensional perspective, no statistical difference was found between the treatments for the variables under study. Conclusion: this study implemented and normalized an immunohistochemical technique for the tissue immunolocation of CYP 1A that could be used in future investigations to fulfill biomonitoring of contamination in Colombia's hydrographic basins.


Resumo Na Colômbia são escassas as técnicas de diagnóstico realizadas com biomarcadores imuno-histoquímicos para realizar biomonitoramento da contaminação ambiental. Objetivo: Estandardizar uma técnica imuno-histoquímica para fazer imunolocalização do CYP 1ª em tecidos de peixes, logo de realizar um experimento de exposição subaguda ao Clorpirifós em machos juvenis de tilápia. Métodos: O teste da dose subletal realizou-se num sistema semiestático, com recambio diário de 50% do volume de água mantendo a concentração correspondente em cada grupo experimental mediante a adição da metade da dose até o dia 28. As concentrações de Clorpirifós para a exposição dos peixes foram 4, 8 e 12 μg/L, nos grupos tratados e 0,0 μg/L no grupo controle. Tomaram-se amostras para o estudo histopatológico e imuno-histoquímico. Resultados: Encontrou-se diferença significativa (p<0.05) para lesões no fígado, confirmando que este é um órgão que recebe diretamente o impacto dos efeitos do Clorpirifos em baixas doses. Verificou-se a indução de CYP 1A nos hepatócitos, endotélio e células biliares tanto nos animais que estiveram expostos ao Clorpirifós quanto nos animais que não estiveram expostos. Desde o ponto de vista multidimensional não se encontrou diferença estadística entre os tratamentos para as variáveis estudadas. Conclusão: Estandardizou-se e normalizou-se uma técnica de imuno-histoquímica para a imunolocalização tissular de CYP 1A, que poderá se utilizada em futuras pesquisas para realizar biomonitoramento da contaminação das bacias hidrográficas da Colômbia, além disto.

12.
Neuropsychologia ; 49(12): 3178-87, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21807011

RESUMO

In real-world settings, information from multiple sensory modalities is combined to form a complete, behaviorally salient percept - a process known as multisensory integration. While deficits in auditory and visual processing are often observed in schizophrenia, little is known about how multisensory integration is affected by the disorder. The present study examined auditory, visual, and combined audio-visual processing in schizophrenia patients using high-density electrical mapping. An ecologically relevant task was used to compare unisensory and multisensory evoked potentials from schizophrenia patients to potentials from healthy normal volunteers. Analysis of unisensory responses revealed a large decrease in the N100 component of the auditory-evoked potential, as well as early differences in the visual-evoked components in the schizophrenia group. Differences in early evoked responses to multisensory stimuli were also detected. Multisensory facilitation was assessed by comparing the sum of auditory and visual evoked responses to the audio-visual evoked response. Schizophrenia patients showed a significantly greater absolute magnitude response to audio-visual stimuli than to summed unisensory stimuli when compared to healthy volunteers, indicating significantly greater multisensory facilitation in the patient group. Behavioral responses also indicated increased facilitation from multisensory stimuli. The results represent the first report of increased multisensory facilitation in schizophrenia and suggest that, although unisensory deficits are present, compensatory mechanisms may exist under certain conditions that permit improved multisensory integration in individuals afflicted with the disorder.


Assuntos
Percepção Auditiva/fisiologia , Mapeamento Encefálico , Esquizofrenia/patologia , Esquizofrenia/fisiopatologia , Percepção Visual/fisiologia , Estimulação Acústica/métodos , Adulto , Eletroencefalografia , Potenciais Evocados Auditivos/fisiologia , Potenciais Evocados Visuais/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Estatística como Assunto , Adulto Jovem
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