Mast cells, known as pro‐inflammatory effector cells, are immunocytes present in the meninges and may be involved in the pathophysiology of migraine. This study aims to evaluate the histomorphometric ...parameters of mast cells located in the convexity of the human intracranial dura mater. For this, samples of intracranial dura mater from eight human fresh cadavers were collected between 8‐ and 24‐h post‐mortem. The whole samples were fixed and, subsequently, two fragments of 1.5 cm² each were cut from four different areas of the dura mater convexity, containing a segment of the middle meningeal artery, totaling 64 fragments. After histological processing, the fragments were submitted to microtomy (5 and 10 µm), stained with toluidine blue (0.1%), or immunohistochemically labeled for tryptase, and analyzed using optical microscopy. The following histomorphometric parameters were evaluated: distance from mast cells to vessels, the density of mast cells, and percentage of mast cells with degranulation. Histomorphometric analyzes showed a higher density of mast cells in the vicinity of blood vessels (arterial and venous), with distances around 0–150 µm. A greater number of mast cells was detected near venous vessels in the periosteal layer (17.0 ± 10.1 cells/mm²) than in the meningeal layer (14.1 ± 7.0 cells/mm²) (p < 0.05). Mast cells from the region close to the superior sagittal sinus were found in greater quantity close to the venous vessels (16.7 ± 10.1 cells/mm²) than to the arterial vessels (11.2 ± 7.5 cells/mm²) (p < 0.05). In short, in the convexity of the human intracranial dura mater, mast cells are located close to blood vessels, with a greater number of cells next to the venous vessels of the periosteal layer and in the proximal region of the superior sagittal sinus.
The mast cells observed in the convexity of human intracranial dura are located near arterial and venous vessels. A higher density of the mast cells is in the vicinity of venous vessels in the periosteal layers and proximal to the superior sagittal sinus.
Dengue is one of the main public health concerns worldwide. Recent estimates indicate that over 390 million people are infected annually with the dengue virus (DENV), resulting in thousands of ...deaths. Among the DENV nonstructural proteins, the NS1 protein is the only one whose function during replication is still unknown. NS1 is a 46- to 55-kDa glycoprotein commonly found as both a membrane-associated homodimer and a soluble hexameric barrel-shaped lipoprotein. Despite its role in the pathogenic process, NS1 is essential for proper RNA accumulation and virus production. In the present study, we identified that glyceraldehyde-3-phosphate dehydrogenase (GAPDH) interacts with intracellular NS1. Molecular docking revealed that this interaction occurs through the hydrophobic protrusion of NS1 and the hydrophobic residues located at the opposite side of the catalytic site. Moreover, addition of purified recombinant NS1 enhanced the glycolytic activity of GAPDH in vitro. Interestingly, we observed that DENV infection promoted the relocalization of GAPDH to the perinuclear region, where NS1 is commonly found. Both DENV infection and expression of NS1 itself resulted in increased GAPDH activity. Our findings indicate that the NS1 protein acts to increase glycolytic flux and, consequently, energy production, which is consistent with the recent finding that DENV induces and requires glycolysis for proper replication. This is the first report to propose that NS1 is an important modulator of cellular energy metabolism. The data presented here provide new insights that may be useful for further drug design and the development of alternative antiviral therapies against DENV.
Dengue represents a serious public health problem worldwide and is caused by infection with dengue virus (DENV). Estimates indicate that half of the global population is at risk of infection, with almost 400 million cases occurring per year. The NS1 glycoprotein is found in both the intracellular and the extracellular milieus. Despite the fact that NS1 has been commonly associated with DENV pathogenesis, it plays a pivotal but unknown role in the replication process. In an effort to understand the role of intracellular NS1, we demonstrate that glyceraldehyde-3-phosphate dehydrogenase (GAPDH) interacts with NS1. Our results indicate that NS1 increases the glycolytic activity of GAPDH in vitro. Interestingly, the GAPDH activity was increased during DENV infection, and NS1 expression alone was sufficient to enhance intracellular GAPDH activity in BHK-21 cells. Overall, our findings suggest that NS1 is an important modulator of cellular energy metabolism by increasing glycolytic flux.
Abstract
Background
Although working activities are associated with several pregnancy outcomes, there is scarce information regarding the association between working activities and low back pain ...(LBP) during pregnancy. This study aimed to investigate whether leisure-time and work-related physical activities during pregnancy are associated with LBP.
Methods
Data from the 2015 Pelotas Birth Cohort study were used. Demographic, socioeconomic, gestational, leisure-time (prior to and during pregnancy) and work-related (days of work, hours of work, standing and heavy lifting) physical activity data were collected at birth. LPB was assessed in the 12-month follow-up period.
Results
Leisure-time physical activity either prior to and during pregnancy was not associated with LBP. Working during pregnancy, days of work and standing position at work were not associated with self-reported LBP during pregnancy. However, working more than 8 h per day and always lifting heavy objects at work increased the odds ratio for LBP (OR 1.30 95%CI: 1.04; 1.63; and OR: 1.39 95%CI 1.08; 1.81, respectively). In addition, women who had lifted heavy objects often/always, reported an increase in pain intensity.
Conclusion
Working during pregnancy and days worked per week were not related to experiencing LBP. However, women who worked more than 8 h per day, as well as women who lifted heavy objects at work on a regular basis, were more likely to experience pregnancy-related LBP.
Abstract Since the first reported case of COVID-19 in Brazil, the public and private educational system started to close. Up to November 2020, scientific discussions about the return of schooling ...activities have been rarely performed by the national scientific community and police-makers. The great delay of school returning in Brazil contrasts with successful international strategies of school reopening worldwide and seems counterintuitive with the reopening of non-essential activities. Here, important issues to be considered before and during school reopening are reviewed and discussed. COVID-19 testing is essential to avoid disease spreading, but high cost of individual RT-qPCRs impairs an extensive testing strategy for school returning. To reduce costs and increase the speed of diagnosis, we tested the efficiency of a pooled-sample PCR strategy in a cohort of the educational staff in the city of Macaé/RJ, finding five asymptomatic individuals (0,66%) among the 754 people tested. Thus, a polled-sample PCR testing strategy of the educational staff might prevent infection spreading in schools at a reasonable cost. We discuss how our test strategy could be coupled with internationally recognized safety rules to allow for a safe school return and how countries from different world regions are dealing with educational activities during COVID-19 pandemic.
Coronavirus disease (COVID-19) pandemic has infected 630 million people and led to 6.59 million deaths worldwide since its outbreak. To control COVID-19 advance, finding new molecules with potential ...to inhibit viral spread is pivotal. Papain-like protease (PLpro) is one of the most interesting targets of pharmacological inhibition since it is implicated not only in viral replication but also in modulation of host immune response. Natural products are of great interest to the pharmaceutical industry due to their diverse structure and biological activities. The NuBBEDB (Nuclei of Bioassays, Biosynthesis and Ecophysiology of Natural Products Database) is an excellent source of natural products (NPs) from the Brazilian flora. In this study, we performed virtual screening, molecular dynamics, and binding energy analyses of the NuBBEDB library to target severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) papain-like protease (PLpro), the virus’s protease essential for replication. Among the top-ranked molecules, the indole alkaloids raputindoles A, C, and D emerged as potential SARS-CoV-2 inhibitors, showing significant interactions with the pivotal Beta-Loop-2 (BL2) region, including the catalytic Y268 residue. Notably, raputindole D displayed enhanced stabilization of the BL2 region, while raputindole C exhibited superior overall stability. These in silico findings suggest that raputindoles, especially D, might offer therapeutic value against COVID-19, laying the groundwork for further experimental evaluations.
ObjectiveTo describe all the procedures of a study that will replicate a previous case-crossover study investigating physical and psychosocial transient exposure risk factors for triggering an ...episode of acute non-specific low back pain (LBP) at emergency departments in an emerging country.MethodsThis case-crossover study will recruit 350 patients, aged between 18 and 80 years, with a new episode of acute non-specific LBP seeking care at emergency departments from public hospitals in Brazil. We will collect information about exposure to a range of physical (eg, awkward postures, lifting children or animals, vigorous physical activity) and psychosocial triggers (eg, distraction, tiredness, alcohol consumption) that were examined in the previous study. The exposure to each trigger during the 2 hours preceding the onset of LBP (case window) will be compared with exposure in the 2-hour periods ending 24 (24–26 hours) and 48 (48–50 hours) hours before the onset of back pain (control window). Conditional logistic regression models will be built to estimate ORs expressing the magnitude of increased risk of developing LBP associated with each factor.DiscussionThis study will enable the confirmation of previous findings regarding transient exposure to factors that increase risk for an episode of acute LBP in a different setting (at emergency departments of an emerging country). To minimise the potential for recall bias, the maximum time between episode onset and interview will be 7 days; we will encourage participants to use their smartphones and diaries to remember the investigated period. Also, our interview script asked participants to nominate the key aspects of each day. Despite these efforts, the retrospective study design means it is not possible to completely exclude potential for recall bias. Furthermore, participants will be blinded to the case and control periods.Ethics and disseminationEthics were granted by the Research Ethics Committee (#20310219.8.0000.0064). Study findings will be disseminated through publications and conference presentations.
The increased marketing of fake perfumes has encouraged us to investigate how to identify such products by their chemical characteristics and multivariate analysis. The aim of this study was to ...present an alternative approach to distinguish original from fake perfumes by means of the investigation of sodium, potassium, chloride ions, and ethanol contents by chemometric tools. For this, 50 perfumes were used (25 original and 25 counterfeit) for the analysis of ions (ion chromatography) and ethanol (gas chromatography). The results demonstrated that the fake perfume had low levels of ethanol and high levels of chloride compared to the original product. The data were treated by chemometric tools such as principal component analysis and linear discriminant analysis. This study proved that the analysis of ethanol is an effective method of distinguishing original from the fake products, and it may potentially be used to assist legal authorities in such cases.
Adipose tissue is involved in many physiological processes. Therefore, the need for adipose tissue-like analogues either for soft tissue reconstruction or as in vitro testing platforms is undeniable. ...In this work, we explored the natural features of gellan gum (GG) to recreate injectable stable adipose-like microtissues. GG hydrogel particles with different percentages of polymer (0.5%, 0.75%, 1.25%) were developed and the effect of obtained mechanical properties over the ability of hASCs to differentiate towards the adipogenic lineage was evaluated based on the expression of the early (PPARγ) and late (FABP4) adipogenic markers, and on lipids formation and accumulation. Constructs were cultured in adipogenic induction medium up to 21 days or for six days in induction plus nine days in maintenance media. Overall, no significant differences were observed in terms of hASCs adipogenic differentiation within the range of Young's moduli between 2.7 and 12.9 kPa. The long-term (up to six weeks) stability of the developed constructs supported its application in soft tissue reconstruction. Moreover, their ability to function as adipose-like microtissue models for drug screening was demonstrated by confirming its sensitivity to TNFα and ROCK inhibitor, respectively involved in the repression and induction of the adipogenic differentiation.
The dermal papilla (DP), a specialized compartment within the hair follicle, regulates hair growth. However, human DP cells rapidly lose their inductivity in 2D-culture given the loss of positional ...and microenvironmental cues. Spheroids have been capable of recreating the 3D intercellular organization of DP cells, however, DP cell-matrix interactions are poorly represented. Considering the specific nature of the DP's extracellular matrix (ECM), we functionalized gellan gum (GG) with collagen IV-(HepIII) or fibronectin-(cRGDfC) derived peptide sequences to generate a 3D environment in which the phenotype and physiological functions of DP cells are restored. We further tuned the stiffness of the microenvironments by varying GG amount. Biomimetic peptides in stiffer hydrogels promoted the adhesion of DP cells, while each peptide and amount of polymer independently influenced the type and quantity of ECM proteins deposited. Furthermore, although peptides did not seem to have an influence, stiffer hydrogels improved the inductive capacity of DP cells after short term culture. Interestingly, independently of the peptide, these hydrogels supported the recapitulation of basic hair morphogenesis-like events when incorporated in an organotypic human skin in vitro model. Our work demonstrates that tailored GG hydrogels support the generation of a microenvironment in which both cell-ECM and cell-cell interactions positively influence DP cells towards the creation of an artificial DP.
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•Dermal papilla (DP) cells rapidly lose their native properties in culture, which has prevented further advances in human hair regeneration.•We propose the conjugation of gellan gum (GG) hydrogels with collagen IV-(HepIII) or fibronectin-(cRGDfC) related peptides as a strategy to recover the hair inductive features of DP cells.•We demonstrate that biofunctionalized hydrogels with increased stiffness (1.25% vs 0.75% GG), were capable of improving DP cell inductivity during short term cultures.•The incorporation of the cell-laden GG hydrogels in a human skin model allowed the recapitulation of basic hair morphogenesis events in vitro, meeting basic requirements of an artificial DP.
The data described here supports the research article “Unraveling HIV Protease Flaps Dynamics by Constant pH Molecular Dynamics Simulations” (Soares et al., 2016) 1. The data involves both standard ...Molecular Dynamics (MD) and Constant pH Molecular Dynamics (CpHMD) to elucidate the effect of protonation states of catalytic dyad on the HIV-PR conformation. The data obtained from MD simulation demonstrate that the protonation state of the two aspartic acids (Asp25/Asp25′) has a strong influence on the dynamics of the HIV-PR. Regarding the CpHMD simulation, we performed pka calculations for HIV-PR and the data indicate that only one catalytic aspartate should be protonated.
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