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•Eoarchean zircon grains are preserved in the sediments of the Carajás Basin.•The Carajás Domain contains relicts of a Paleo- to early Mesoarchean basin.•The Carajás Domain hosts the ...Neoarchean Parauapebas Large Igneous Province.•The LIP immediately preceded a period of continental extension that formed a rift.•The Carajás Basin evolved to a Transamazonian back-bulge basin.
Despite representing one of the largest cratons on Earth, the early geological evolution of the Amazonia Craton remains poorly known due to relatively poor exposure and because younger metamorphic and tectonic events have obscured initial information. In this study, we investigated the sedimentary archives of the Carajás Basin to unravel the early geological evolution of the southeastern Amazonia Craton. The Carajás Basin contains sedimentary rocks that were deposited throughout a long period spanning more than one billion years from the Mesoarchean to the Paleoproterozoic. The oldest archives preserved in this basin consist of a few ca. 3.6 Ga detrital zircon grains showing that the geological roots of the Amazonia Craton were already formed by the Eoarchean. During the Paleoarchean or the early Mesoarchean (<3.1 Ga), the Carajás Basin was large and rigid enough to sustain the formation and preservation of the Rio Novo Group greenstone belt. Later, during the Neoarchean, at ca. 2.7 Ga, the southeastern Amazonia Craton witnessed the emplacement of the Parauapebas Large Igneous Province (LIP) that probably covered a large part of the craton and was associated with the deposition of some of the world largest iron formations. The emplacement of this LIP immediately preceded a period of continental extension that formed a rift infilled first by iron formations followed by terrigenous sediments. This major change of sedimentary regime might have been controlled by the regional tectonic evolution of the Amazonia Craton and its emergence above sea-level. During the Paleoproterozoic, at ca. 2.1 Ga, the Rio Fresco Group, consisting of terrigenous sediments from the interior of the Amazonia Craton, was deposited in the Carajás Basin. At that time, the Amazonian lithosphere could have either underwent thermal subsidence forming a large intracratonic basin or could have been deformed by long wavelength flexures that induced the formation of basins and swells throughout the craton under the influence of the growing Transamazonian mountain belt.
ABSTRACT
Different types of topical preparations are available as anti-psoriatic medicines, semisolid formulations being the preferred dosage forms for the treatment of body lesions. The mechanical ...characterization of these semisolid formulations is seldom reported, although mechanical features have been recognized to play an important role in treatment acceptability and adherence. The aim of this study was to characterize the mechanical properties of semisolid topical formulations commercially available for psoriasis treatment. One complementary aim was to evaluate patient satisfaction with topical treatment and discuss the results according to the mechanical features of the dosage form. Eight ointments (O 1–8), five creams (C 1–5), one oleogel (G1), and one excipient (E1—petrolatum) were characterized for textural properties (spreadability and penetration tests) and flow behavior. Power law model was fitted to the results. A questionnaire for the assessment of satisfaction with topical medicines used for psoriasis treatment over 6 months was developed and applied to 79 psoriasis patients. All the tested formulations presented a shear-thinning behavior with power law indexes (
n
) lower than 1. Ointments were distinct from the other dosage forms, since they presented higher consistency coefficients (
K
), firmness, and adhesiveness and this was evidenced by hierarchical cluster analysis, which identified two clusters based on the mechanical properties. Cluster 1 included the ointments and petrolatum and the cluster 2 enclosed the creams and the gel. The clusters were associated with several attributes classified by patients as analyzed with Fisher’s exact test. In all cases, higher satisfaction was observed for cluster 2. The knowledge obtained regarding the influence of the dosage form on the degree of satisfaction with the treatment could be helpful in supporting the selection of the dosage form in clinical practice and thus improve treatment adherence and clinical outcomes. The differences observed between the mechanical properties of the formulations studied may be also relevant to the industry, as guidance to the development of new medicines.
Abstract Background Liver transplantation is a controversial issue in the initial management of hepatocellular carcinoma (HCC). The aim of this study was to demonstrate that up-to-seven could be ...useful as a model in evaluating potential candidates for liver transplantation for HCC. Methods Between January 1997 and December 2010, 84 patients undergoing liver transplantation were analyzed for HCC. Pathologic variables included the number of lesions, maximal tumor diameter, vascular invasion, and tumor grade. The following variables were recorded: Age, gender, recurrence of HCC, survival, donor age, incidental, Milan criteria, Model for End-Stage Liver Disease score, and alpha-fetoprotein (AFP) levels. To evaluate variables we used the Kaplan–Meier method, Cox regression and Kolmogorov-Smirnov test. Results There were 68 (80.9%) patients within up-to-seven criteria and 16 (19.1%) beyond this criteria. AFP levels were 96.4 versus 464.3 ng/dL in patients within versus beyond up-to-seven criteria. The median diameter of the largest nodule was 22.2 versus 32.0 mm in patients within versus beyond up-to-seven criteria, respectively. The median sum of nodules was 1.8 and 5.6 nodules in patients within versus beyond up-to-seven criteria. Vascular invasion was present in 11 (13.0%) patients within versus 7 (8.3%) beyond. Recurrence was observed in 9 (10.7%) patients and only 3 were beyond up-to-seven criteria, 2 had vascular invasion, and another showed poor differentiation. Post liver transplantation survival rates were 87.7%, 74.5%, and 65.3% at 1, 3, and 5 years in patients within up-to-seven versus 80.7%, 51.7%, and 32.1% beyond ( P = .03). Similar results were observed when we applied Milan criteria or expanded Milan criteria. The largest nodule was the only predictive factor after proportional hazard Cox regression application (Beta = 0.037; exponent = 1.0377; Wald = 4.542; P = .03). In the present study, up-to-seven criteria could be useful to evaluate potential liver transplant candidates due to HCC.
The aim of this study was to determine whether highly active antiretroviral therapy (HAART) is associated with the prevalence of oral lesions in HIV-positive patients. This systematic review and ...meta-analysis was performed in accordance with the PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). The search was conducted in seven electronic databases (PubMed, Scopus, SciELO, LILACS, Embase, Web of Science, and OpenGrey), without restriction on publication period or language. Studies that showed the prevalence of oral lesions manifested in adult HIV-positive patients, subjected or not to HAART, were selected. The meta-analysis estimate of relative risk was calculated using the Mantel–Haenszel method and DerSimonian and Laird estimator to determine the variance between studies in the random-effects model. The meta-analysis showed significant results in favour of the group on HAART, with lower prevalence for angular cheilitis, erythematous candidiasis, oral herpes, pseudomembranous candidiasis, Kaposi sarcoma, and oral hairy leukoplakia. The prevalence of oral mucosal hyperpigmentation was higher in patients on HAART. These results suggest that the prevalence of oral lesions in HIV-positive patients is lower for those on HAART, which might occur because of the improvement in immunity provided by the therapy.
Abstract
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with a hyperinflammatory state and lymphocytopenia, a hallmark that appears as both signature and ...prognosis of disease severity outcome. Although cytokine storm and a sustained inflammatory state are commonly associated with immune cell depletion, it is still unclear whether direct SARS-CoV-2 infection of immune cells could also play a role in this scenario by harboring viral replication. We found that monocytes, as well as both B and T lymphocytes, were susceptible to SARS-CoV-2 infection in vitro, accumulating double-stranded RNA consistent with viral RNA replication and ultimately leading to expressive T cell apoptosis. In addition, flow cytometry and immunofluorescence analysis revealed that SARS-CoV-2 was frequently detected in monocytes and B lymphocytes from coronavirus disease 2019 (COVID-19) patients. The rates of SARS-CoV-2-infected monocytes in peripheral blood mononuclear cells from COVID-19 patients increased over time from symptom onset, with SARS-CoV-2-positive monocytes, B cells, and CD4+ T lymphocytes also detected in postmortem lung tissue. These results indicated that SARS-CoV-2 infection of blood-circulating leukocytes in COVID-19 patients might have important implications for disease pathogenesis and progression, immune dysfunction, and virus spread within the host.
Assessment of toxic effects is mandatory before market placement of pharmaceutical and cosmetic products. Nanotoxicology is an emerging regulatory concern and still a challenging field. Topical ...application of resveratrol (RSV) has been extensively studied owing to its multi-mechanistic skin anti-aging effects. Nanoencapsulation has been suggested as a promising solution to overcome RSV stability issues. In this work RSV-loaded solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) were prepared using a homogenization/sonication technique. Cytotoxicity assays were conducted with an immortalized cell line of human keratinocytes (HaCaT). For a comprehensive cytotoxicity characterization MTT and Alamar Blue® reduction assays (assessment of metabolic activity), Neutral red uptake (evaluation of lysosomal integrity), and Trypan blue (assessment of membrane integrity) were used. The results obtained with the different assays were not always concordant, as put in evidence by an adequate statistical analysis. Experimental parameters such as washing steps were found to be critical. The study is of interest because it draws attention to the importance of careful selected experimental conditions of in vitro nanotoxicological tests. Experimental protocols should be adapted taking into account nano-related features such as interference with the dyes and light dispersion/absorption properties.
•SLN/NLC particles loaded with resveratrol were developed.•A concentration dependent cytotoxic effect on HaCaT cells was observed.•Four different in vitro cytotoxicity assays provided inconsistent results.•Experimental parameters such as washing steps were found to be critical.
•C. sativa extract showed a protective effect against UV mediated-DNA damage.•This effect was found to be related to a direct antioxidant effect involving 1O2.•The extract does not activate the ...endogenous antioxidant defences involving NRF2.•Reducing properties are associated with the presence of a pool of antioxidants.
Toxic effects of ultraviolet (UV) radiation on skin include protein and lipid oxidation, and DNA damage. The latter is known to play a major role in photocarcinogenesis and photoaging. Many plant extracts and natural compounds are emerging as photoprotective agents. Castanea sativa leaf extract is able to scavenge several reactive species that have been associated to UV-induced oxidative stress. The aim of this work was to analyze the protective effect of C. sativa extract (ECS) at different concentrations (0.001, 0.01, 0.05 and 0.1μg/mL) against the UV mediated-DNA damage in a human keratinocyte cell line (HaCaT). For this purpose, the cytokinesis-block micronucleus assay was used. Elucidation of the protective mechanism was undertaken regarding UV absorption, influence on 1O2 mediated effects or NRF2 activation. ECS presented a concentration-dependent protective effect against UV-mediated DNA damage in HaCaT cells. The maximum protection afforded (66.4%) was achieved with the concentration of 0.1μg/mL. This effect was found to be related to a direct antioxidant effect (involving 1O2) rather than activation of the endogenous antioxidant response coordinated by NRF2. Electrochemical studies showed that the good antioxidant capacity of the ECS can be ascribed to the presence of a pool of different phenolic antioxidants. No genotoxic or phototoxic effects were observed after incubation of HaCaT cells with ECS (up to 0.1μg/mL). Taken together these results reinforce the putative application of this plant extract in the prevention/minimization of UV deleterious effects on skin.
Abstract Background Hepatic artery thrombosis (HAT) is reported in 4%-15% of orthotopic liver transplants. Risk factors include technical error in the anastomosis, vascular anatomic variation, and ...high microvascular resistance. The aim of this study was to verify the incidence of HAT, early or late, and possible risk factors. Methods This was a retrospective study from January 2007 to December 2012 at the State University of Campinas. Variables analyzed were age, sex, cold and warm ischemia times, underlying disease, presence of hepatocellular carcinoma, Model for End-Stage Liver Disease (MELD) score, arterial anatomic variation in the graft, cytomegalovirus (CMV) infection, rejection, biliary complications, retransplantation rate, and survival. Results The incidence of HAT was 21/263, or 7.9%. Pure average MELD score was 22 ± 7.4. There was vascular anatomic variation in the graft in 14.2% of cases, in the majority (66.6%) a right hepatic artery from the superior mesenteric artery, and 4.76% of patients had CMV infection and acute cellular rejection (1 case each). There were biliary complications in 38% of patients, 13.3% of cases in patients with early HAT, and 100% of patients with late HAT ( P = .002). Body mass index in late HAT was higher ( P = .01). Conclusions Late HAT was related to a significant increase in biliary complications (stenosis), and the survival rate was similar at 5 years.
Abstract
Background
A methodology to identify patients with ascending aortic aneurysm (AsAA) under high risk of aortic growth is not completely defined.
Objective
This research seeks to numerically ...characterize the blood flow and relate resulting stress distribution with AsAA growth.
Methods
Analytical, observational, single-center study in which a computational fluid dynamics (CFD) protocol was applied to aortic Computed Tomography Angiogram (CTA) images of patients with AsAA. Two (CTA) exams with at least one year of difference were obtained. From the CTA-gathered images, three-dimensional models were generated, and clinical data were registered. Study of velocity field and coherent structures (vortices) was performed aiming to relate them to aneurysm growth or non-growth, and thereafter to compare with the clinical data of these patients. Kolmogorov-Smirnov test was used to evaluate the normality distribution and for non-normal distribution, the non-parametric Wilcoxon signed-rank test was applied for comparisons of paired data of the aortic angles. Statistical significance was set at 5%.
Results
The incident jet in the aortic wall generated recirculation areas in the posterior region of the jet, inducing complex vortices formation, for the group that presented aneurysm growth, leading to an increase of the average pressure at the ascending aortic wall (Fig. 1), between exams. While for the group without aneurysm growth, the average pressure decreased.
Conclusion
This pilot study showed that CFD based upon CTA may in the near future be a tool to help identify flow patterns associated with AsAA remodeling process.
Funding Acknowledgement
Type of funding sources: None. Figure 1. Axialvelocity. Iso-surface-without-growthFigure 2. Isosurface of Q-criterion. Without growth
Aim
To compare the martensitic transformation temperatures and torsional resistance behaviour of classic M‐Wire Reciproc and Reciproc blue files (VDW, Munich, Germany).
Methodology
M‐Wire classic ...Reciproc R25 and Reciproc blue R25 instruments were used. Transformation temperatures were determined by differential scanning calorimetry (DSC‐DSC 60, Shimadzu, Kyoto, Japan). Three samples with approximately 20 mg of each system were cooled to −120 °C and then heated to 100 °C and then cooled to –100 °C at a rate of 10 °C min−1. The maximum torque values and angular deflection until fracture of new instruments (n = 10) were measured according to ISO 3630‐1. Results were analysed statistically using the Student's t‐test at a significance level of P < 0.05.
Results
DSC results revealed the absence of martensitic transformation for Reciproc instruments in the temperature range analysed. In both systems, the instruments were composed of a mixture of R‐phase and austenite at room temperature. After torsional tests, Reciproc blue had significantly lower values for mean maximum torque at rupture (P < 0.05), although the angular deflection values were significantly higher than the Reciproc classic group (P < 0.05).
Conclusions
Both Reciproc and Reciproc blue instruments were composed of a mixture of R‐phase and austenite. Reciproc Blue instruments had a greater angle of rotation to fracture but a lower torque to failure than M‐Wire Reciproc instruments.
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