Nucleotide-Binding Oligomerization Domain-1 and -2 Play No Role in Controlling Brucella abortus Infection in Mice

Nucleotide-binding oligomerization domain proteins (NODs) are modular cytoplasmic proteins implicated in the recognition of peptidoglycan-derived molecules. Further, several in vivo studies have demonstrated a role for Nod1 and Nod2 in host defense against bacterial pathogens. Here, we demonstrated that macrophages from NOD1-, NOD2-, and Rip2-deficient mice produced lower levels of TNF-α following infection with live Brucella abortus compared to wild-type mice. Similar reduction on cytokine synthesis was not observed for IL-12 and IL-6. However, NOD1, NOD2, and Rip2 knockout mice were no more susceptible to infection with virulent B. abortus than wild-type mice. Additionally, spleen cells from NOD1-, NOD2-, and Rip2-deficient mice showed unaltered production of IFN-γ compared to C57BL/6 mice. Taken together, this study demonstrates that NOD1, NOD2 and Rip2 are dispensable for the control of B. abortus during in vivo infection

Epstein Barr virus detection in cervical samples of women living with human immunodeficiency virus

O vírus Epstein-Barr (EBV) é transmitido comumente pela saliva, mas pode ser encontrado também em secreções genitais, sugerindo transmissão sexual e levando pesquisadores a associar este vírus à neoplasia cervical. Pessoas infectadas pelo virus da imunodeficiência humana (HIV) são de alto risco para aquisição de infecções genitais e lesões de cérvice uterina. Com o objetivo de verificar a presença do DNA do EBV no trato genital e/ou se poderia ter efeito em alterações cervicais, analisamos esfregaços cervicais de 85 mulheres HIV soropositivas. O vírus foi detectado em apenas duas (2,3%) amostras. O presente estudo não fornece evidência da transmissão sexual do EBV, nem descarta esta possibilidade.Epstein Barr Virus (EBV) is transmitted commonly by saliva, but it has been found in genital secretions, which suggests sexual transmission and led researchers to connect EBV and cervical neoplasia. People living with human immunodeficiency virus (HIV) are reported to be at high risk of acquiring genital infections and cervical lesions. To verify the presence of EBV in the genital tract and/or it could affect cervical changes, we analyzed cervical smears from 85 HIV seropositive women for EBV DNA determination. EBV was only detected in two (2.3%) samples. The present study provides neither evidence for EBV as sexually transmitted infection nor discards this possibility

The gastropod statolith elemental composition by EPMA

Gastropods statoliths are biogenic structures of CaCO3, analogous to fish otoliths. Their application in sclerochronology is recent and may be advantageous comparing to the most traditional organisms used hitherto. Moreover, since elements bind within calcified structures, statoliths theoretically incorporate chemical information from the surrounding environment over time. So, besides being used for age estimation and growth studies, statoliths elemental fingerprinting is recognized as natural tag to track larval dispersal and may also be considered as a potential marker of environmental change and/or pollution. However there is a lack of information on the elemental composition of adult gastropod statoliths. Here we characterize Nassariusreticulatus (Gastropoda: Caenogastropoda) statoliths elemental composition by electron microprobe analysis (EMPA).One statolith from each of 3 adults was prepared for EMPA (Figure 1) and showed the same structural pattern: a nucleus circled by a metamorphic ring and, in addition to this core, 4 other rings delineating 5 increments (Figure 1F). General composition was assessed by Energy and Wavelength Dispersive Spectroscopy revealing C, Ca, O, Sr, Na, S and Mg as the most representative elements. These were then quantified in 3 points per increment. Carbon was not determined since surfaces were C-coated and the amount of oxides of Ca, Sr, Na, S and Mg was estimated from the valence. In addition, Ba – trace element in statoliths of some gastropods larvae – and Al, Cu, Hg, Sn – known as environmental pollutants – were also sought in one of the statoliths. For such, mean values for Ca, Sr, Na, S, Mg and O were set as the sample matrix. Standards and mean detection limits by element and statolith are indicated in Table 1.Concentrations of Ca, O, Na, Sr and S varied between 3.7x105-4.2x105, 1.5x105-1.7x105, 2.5x103-6.1x103, 1.3x103-8.9x103 and 4.7x102-1.3x103 ppm, respectively; Mg, which was not always detected, ranged from 2.0x102-8.6x102 ppm. No significant differences in these elements mean concentrations were found between increments, except Na in one statolith between increments 1 and 5 (higher at the edge; Dunn’s test s=2.014, p&gt;0.05). Thus the general elemental composition is nearly constant throughout lifespan (i.e. along statoliths radiuses). Regarding trace elements: Sn was never detected; Al and Hg were at 22.2% of the punctual analyses conducted while Cu was at 66.7% and Ba at 88.9%. Concentrations of Al, Hg, Cu and Ba varied between 55-71, 176-180, 183-302 and 647-969 ppm, respectively.EMPA proved to be a useful technique in sclerochronology, allowing the characterization of the overall composition of gastropods statoliths and the quantification of elements in specific locations with high resolution.This work was supported by the Portuguese Foundation for Science and Technology (FCT) through the grant SFRH/BPD/70368/2010.</jats:p

A ubiquitous learning approach on robotics

Ubiquitous learning refers to the integration of learning processes with everyday environments and activities using technology. By leveraging ubiquitous learning principles in the field of robotics, we can foster an immersive and interactive learning environment that promotes continuous learning and knowledge acquisition. This paper presents an in-depth exploration of a ubiquitous learning approach for robotics with the aim to enhance the educational experiences and capabilities of robotic systems. Furthermore, it explores the potential benefits and challenges of ubiquitous learning in the field of robotics, such as increased adaptability, personalized learning experiences, and the development of lifelong learning skills. The results indicate that a ubiquitous learning approach can significantly enhance the learning capabilities of students.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CeDRI (UIDB/05757/2020 and UIDP/05757/2020) and SusTEC (LA/P/0007/2021).info:eu-repo/semantics/publishedVersio

Host Susceptibility to Brucella abortus Infection Is More Pronounced in IFN-γ knockout than IL-12/β2-Microglobulin Double-Deficient Mice

Brucella abortus is a facultative intracellular bacterial pathogen that causes abortion in domestic animals and undulant fever in humans. IFN-γ, IL-12, and CD8+ T lymphocytes are important components of host immune responses against B. abortus. Herein, IFN-γ and IL-12/β2-microglobulin (β2-m) knockout mice were used to determine whether CD8+ T cells and IL-12-dependent IFN-γ deficiency would be more critical to control B. abortus infection compared to the lack of endogenous IFN-γ. At 1 week after infection, IFN-γ KO and IL-12/β2-m KO mice showed increased numbers of bacterial load in spleens; however, at 3 weeks postinfection (p.i.), only IFN-γ KO succumbed to Brucella. All IFN-γ KO had died at 16 days p.i. whereas death within the IL-12/β2-m KO group was delayed and occurred at 32 days until 47 days postinfection. Susceptibility of IL-12/β2-m KO animals to Brucella was associated to undetectable levels of IFN-γ in mouse splenocytes and inability of these cells to lyse Brucella-infected macrophages. However, the lack of endogenous IFN-γ was found to be more important to control brucellosis than CD8+ T cells and IL-12-dependent IFN-γ deficiencies

2-(2-Methyl-2-nitrovinyl)furan but Not Furvina Interfere with Staphylococcus aureus Agr Quorum-Sensing System and Potentiate the Action of Fusidic Acid against Biofilms

Quorum sensing (QS) plays an essential role in the production of virulence factors, in biofilm formation and antimicrobial resistance. Consequently, inhibiting QS is being considered a promising target for antipathogenic/anti-virulence therapies. This study aims to screen 2-nitrovinylfuran derivatives structurally related to Furvina (a broad-spectrum antibiotic already used for therapeutic purposes) for their effects on QS and in biofilm prevention/control. Furvina and four 2-nitrovinylfuran derivatives (compounds 1-4) were tested to assess the ability to interfere with QS of Staphylococcus aureus using bioreporter strains (S. aureus ALC1742 and ALC1743). The activity of Furvina and the most promising quorum-sensing inhibitor (QSI) was evaluated in biofilm prevention and in biofilm control (combined with fusidic acid). The biofilms were further characterized in terms of biofilm mass, viability and membrane integrity. Compound 2 caused the most significant QS inhibition with reductions between 60% and 80%. Molecular docking simulations indicate that this compound interacts preferentially with the protein hydrophobic cleft in the LytTR domain of AgrA pocket. Metabolic inactivations of 40% for S. aureus ALC1742 and 20% for S. aureus ALC1743 were reached. A 24 h-old biofilm formed in the presence of the QSI increased the metabolic inactivation by fusidic acid to 80%, for both strains. The overall results highlight the effects of compound 2 as well as the potential of combining QSI with in-use antibiotics for the management of skin and soft tissues infections

Can functional exercise capacity discriminate older individuals with poor postural control?

Postural instability can be related to functional limitations as a result of the aging process. This study aimed to compare functional exercise capacity and postural control in older adults. Participants were allocated into three groups according to their functional exercise capacity based on the six minute walking test (6MWT): 1) Low performance group (LP: distance walked ≤ 80% of the predicted value n = 19), 2) Normal performance group (NP: distance walked 81-100% of the predicted value n = 21) and, 3) High performance group (HP: distance walked >100% of the predicted value n = 23). All groups performed three trials of a one-leg stance for 30s on a force platform. LP showed worse postural control in comparison to NP and HP, and significant differences (p < .05) were found between groups for area, velocity antero-posterior of center of pressure and time limit variables during the one-leg stance task. These results have implications for rehabilitation management with regard to exercise, balance assessment and intervention in older adults. Instabilidade postural pode estar relacionada com as limitações funcionais, como um resultado do processo de envelhecimento. Este estudo teve como objetivo comparar a capacidade funcional de exercício e o controle postural em indivíduos idosos. Os participantes foram separados em três grupos de acordo com sua capacidade funcional de exercício baseada no teste de caminhada de seis minutos (TC6min): 1) grupo baixo desempenho (BD: distância caminhada ≤ 80% do valor predito n = 19), 2) grupo normal desempenho (ND : distância caminhada 81-100% do valor predito n = 21) e, 3) grupo alto desempenho (AD: distância caminhada >100% do valor predito n = 23). Todos os grupos realizaram três testes com apoio unipodal permanecendo por 30s sobre a plataforma de força. BD apresentou pior equilíbrio postural em comparação com ND e AD; com diferenças significativas (p < 0,05) encontradas entre os grupos para os parâmetros de área e velocidade antero-posterior do centro de pressão e a variável tempo-limite durante a posição unipodal. Estes resultados têm implicações para estratégias de reabilitação no que diz respeito ao exercício, avaliação do equilíbrio e intervenção em idosos. Inestabilidad postural puede estar relacionada con las limitaciones funcionales como resultado del proceso de envejecimiento. Este estudio tuvo como objetivo evaluar la comparación entre la capacidad funcional del ejercicio en el control postural de las personas de edad avanzada. Los participantes fueron divididos en tres grupos de acuerdo a su capacidad de ejercicio funcional basado en la Prueba de Caminada de seis minutos (PC6M): 1) grupo Bajo Rendimiento (BR: distancia recorrida ≤ 80% del valor predijo, n = 19), 2) grupo Normal Rendimiento (NR: distancia recorrida 81-100% del valor predijo, n = 21) y 3) grupo Alto Rendimiento (AR: distancia recorrida >100% del valor predijo, n = 23). Todos los grupos realizaron tres pruebas sobre un solo pie por 30s en la plataforma de fuerza. BR presentó un mal equilibrio postural en comparación con NR y AR; con diferencias significativas (p < 0,05) encontrado entre los grupos de los parámetros área y velocidad antero-posterior del centro de presión y el límite de tiempo para la postura de una sola pierna. Estos resultados tienen implicaciones para las estrategias de rehabilitación en relación con el ejercicio, la evaluación del equilibrio y la intervención en los ancianos

Vesicle-micelle transition in aqueous mixtures of the cationic dioctadecyldimethylammonium and octadecyltrimethylammonium bromide surfactants

The vesicle-micelle transition in aqueous mixtures of dioctadecyldimethylammonium and octadecyltrimethylammonium bromide (DODAB and C18TAB) cationic surfactants, having respectively double and single chain, was investigated by differential scanning calorimetry (DSC), steady state fluorescence, dynamic light scattering (DLS) and surface tension. The experiments performed at constant up to 1.0 mM total surfactant concentration reveal that these homologue surfactants mix together to form either mixed vesicles and/or micelles, or both of these structures in equilibrium, depending on the relative amount of the surfactants. The main transition melting temperature Tm of the mixed DODAB-C18TAB vesicles is larger than that for the neat DODAB in water owing to the incorporation of C18TAB in the vesicle bilayer, however, little amount of C18TAB having a minor effect on the Tm of DODAB. The surface tension decreases sigmoidally with C18TAB concentration and the inflection point lies around xDODAB ≈ 0.4, indicating the onset of micelle formation owing to saturation of DODAB vesicles by C18TAB molecules and formation of vesicle structures. At low C18TAB concentrations When xDODAB > 0.5 C18TAB molecules are mainly solubilized by the vesicles bilayers, while at high C18TAB concentrations but when xDODAB < 0.25 micelles are dominant. Fluorescence data of the Nile Red probe incorporated in the system at different surfactant molar fractions indicate the formation of micelle and vesicle structures. These structures have apparent hydrodynamic radius RH of about 180 and 500-800 nm, respectively, as obtained by DLS measurements.Fundação para a Ciência e a Tecnologia (FCT