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Abstract: The definition of a suitable mesh to simulate blood flow in the human carotid bifurcation has been investigated. In this research, a novel mesh generation method is proposed: hexahedral cells at the center of the vessel and a fine grid of tetrahedral cells near the artery wall, in order to correctly simulate the large blood velocity gradients associated with specific locations. The selected numerical examples to show the pertinence of the novel generation method are supported by carotid ultrasound image data of a patient‐specific case. Doppler systolic blood velocities measured during ultrasound examination are compared with simulated velocities using 4 different combinations of hexahedral and tetrahedral meshes and different fluid dynamic simulators. The Lin's test was applied to show the concordance of the results. Wall shear stress–based descriptors and localized normalized helicity descriptor emphasize the performance of the new method. Another feature is the reduced computation time required by the developed methodology. With the accurate combined mesh, different flow rate partitions, between the internal carotid artery and external carotid artery, were studied. The overall effect of the partitions is mainly in the blood flow patterns and in the hot‐spot modulation of atherosclerosis‐susceptible regions, rather than in their distribution along the bifurcation. [ABSTRACT FROM AUTHOR]

The problem of face-milling optimisation is revisited in this work, and a numerical model to optimise machining parameters in multi-pass processes is presented. Considering the technological constraints of the machining process, the optimisation algorithm sought to minimise manufacturing costs. The design variables were the depth of cut, the cutting speed and the feed in each pass. Bounds on depth of cut, cutting speed, feed, surface finishing, cutting force, cutting power and tool life were considered as technological constraints. With the machining process operating in a multi-pass way, the depth of cut for each pass depends upon the total volume of material to be removed. In this paper, a new approach based on substituting the depth of cut with a sequence of depths of cut is presented. After generation of feasible values for sequences of depths of cut, the optimal solution was found by searching over the entire domain of design variables using a genetic algorithm based on an elitist strategy. The performance of the developed model is compared with other published models in the literature, and the multi-pass strategy is discussed. [ABSTRACT FROM AUTHOR]

This study aimed to identify by molecular analysis, morphology, chemistry and antioxidant extracts of filamentous fungi isolated from the digestive tract of Phylloicus sp, an aquatic insect that lives on leaf packages in tropical streams and participates together with fungi of the decomposition of plant substrates in aquatic habitats. Insect larvae of Phylloicus sp. were collected in streams in the state of Tocantins, Brazil. Fungi were isolated from the digestive tract of larvae after disinfection and dissection, then described and purified for identification purposes and testing for antioxidant activity. Molecular identity was performed of ITS1 and ITS4, TUB e TEF sequencing. Fungal extracts were produced in 70% ethanol solution and later lyophilized. For analysis of chemical groups of extracts, thin layer chromatography (TLC) was performed in two mobile phases and different developers. Morphology was performed by optical microscopy stained with Toluidine Blue and measurement performed using the ImageJ program. Antioxidant activity performed in TLC and by quantitative method for DPPH and hydrogen peroxide (H2O2) radicals. Four fungi were identified: Endomelanconiopsis endophytica, Myxospora musae, Neopestalotiopsis cubana and Fusarium pseudocircinatum. The TLC showed several spots with acetone/chloroform mobile phase and UV 254 nm developers and I2 vapor. Fungal extracts demonstrate antioxidant action to reduce the DPPH free radical and especially for H2O2 above 50%, E. endophytica 91.6%, M. musae 87.8%, N. cubana 89.5% and 92.3% for F. pseudocircinatum. This study demonstrated that the molecular technique by PCR was satisfactory for identifying fungi, and extracts with numerous chemical groups and potent reducing agents. Thus future work, should be carried out evaluating these four species for industrial use.

The achievement of clinically viable methodologies to simulate the hemodynamics in patient-specific coronary arteries is still a major challenge. Therefore, the novelty of this work is attained by the introduction of the viscoelastic property of blood in the numerical simulations, to study the role of the left coronary artery (LCA) geometry configuration in the atherosusceptibility. Apparently healthy patients were used and four different methodologies were tested. The methodology giving the most accurate results at the same time of having the lowest computational time is the one considering the viscoelastic property of blood and computational fluid dynamics. A Pearson correlation analysis was used to highlight relationships between geometric configuration and hemodynamic descriptors based on the simulated wall shear stress (WSS). The left main stem (LMS) has the greatest atherosusceptibility followed by the left anterior descending artery (LAD) since the relative residence time (RRT) average values are 3.81 and 3.70 Pa -1 , respectively. The geometric parameters with relevant contribution to directional flow change are the cross-sectional areas, especially the one of LMS segment (A LMS ), and the curvature of LMS segment. For LMS and LAD segments, when A LMS increases, blood flow disturbance (r = 0.81 in LMS and r = 0.74 in LAD) and atherosusceptibility (r = 0.84 in LMS and r = 0.85 in LAD) increases. When the LMS curvature decreases, the WSS magnitude (r = 0.80 in LMS and r = 0.83 in LAD) decreases, and disturbance (r=-0.80 in LMS and r=-0.91 in LAD) and atherosusceptibility (r=-0.74 in LMS and r=-0.74 in LAD) increases.

The Brazilian Cerrado biome consists of a great variety of endemic species with several bioactive compounds, and Anadenanthera peregrina (L.) Speg is a promising species. In this study, we aimed to perform phytochemical characterization and evaluate the antioxidant and antibacterial activities against Staphylococcus aureus and Escherichia coli of the hydroethanolic extract of A. peregrina stem bark. The barks were collected in the Botanical Garden of Goiânia, Brazil. The hydroethanolic extract was obtained by percolation and subjected to physicochemical screening, total phenolic content estimation, high-performance liquid chromatography (HPLC) fingerprinting, and antioxidant (IC50 values were calculated for the 2,2-diphenyl-1-picrylhydrazyl assay - DPPH) and antibacterial activity determination. The pH of the extract was 5.21 and density was 0.956 g/cm3. The phytochemical screening indicated the presence of cardiac glycosides, organic acids, reducing sugars, hemolytic saponins, phenols, coumarins, condensed tannins, flavonoids, catechins, depsides, and depsidones derived from benzoquinones. The extract showed intense hemolytic activity. The total phenolic content was 6.40 g GAE 100 g-1. The HPLC fingerprinting analysis revealed the presence of gallic acid, catechin, and epicatechin. We confirmed the antioxidant activity of the extract. Furthermore, the extract did not inhibit the growth of E. coli colonies at any volume tested, but there were halos around S. aureus colonies at all three volumes tested. These results contribute to a better understanding of the chemical composition of A. peregrina stem bark and further support the medicinal applications of this species.

Background: Frontal fibrosing alopecia (FFA) is a lymphocytic scarring alopecia whose worldwide incidence is rising. Environmental triggers combined with genetic predisposition represent one of the current hypotheses in FFA aetiology. Familial clusters are opportunities to investigate the genetic basis of diseases., Objectives: Assess human leucocyte antigen (HLA) genetic variability in a Brazilian sample of a large familial cluster (six sisters and one daughter) with FFA, unnafected familiar members and sporadic cases of FFA., Methods: We addressed the HLA-A, HLA-B, HLA-C, HLA-G and HLA-E genetic variability in this family and in seven sporadic FFA cases, comparing allele frequencies with those reported for the São Paulo State from Brazil., Results: Two susceptibility haplotypes, C*17:01:01:02/B*42:01:01:01 and C*07:02:01:03/B*07:02:01:01, were identified among familial cases and also in sporadic cases. The first haplotype is rare among Brazilians, and it was not previously reported as being associated with FFA. Both alleles were found in some different unaffected familiars, what emphasizes the role of environmental triggers in disease development. HLA-A, HLA-G and HLA-E genes were not associated to familiar nor FFA sporadic cases., Conclusion: The identification of susceptibility haplotypes in FFA reinforces the genetic predisposition to the disease., (© 2020 European Academy of Dermatology and Venereology.)

Introduction: Pre-eclampsia (PE) is a complication of human pregnancy characterized by hypertension and proteinuria after 20 weeks of gestation. In addition to increased activation of monocytes and granulocytes, there is an elevated production of proinflammatory cytokines in pregnant women with PE. The nuclear transcription factor-kB (NF-kB) is present in the cells of the immune system and is responsible for transcription of genes related to inflammation. Whereas the PE is associated with intense inflammatory response, the use of substances modulating the activity of NF-kB factor could be useful in alleviating the inflammation present in these patients. Silibinin is the main component of silymarin, a polyphenolic extract obtained from fruits and seeds of Sylibum marianum with potent hepatoprotective, anti-inflammatory and anti-fibrotic activities., Objectives: The objective of this study was to assess whether silibinin modulates the activity of NF-kB and the production of inflammatory cytokines by mononuclear cells of patients with PE., Methods: We evaluated 34 pregnant women with PE, 20 normotensive pregnant women (NT) and 15 non-pregnant women (NP). Mononuclear cells (PBMC) were obtained from peripheral blood and cultured in the presence or absence of silibinin (50uM) and stimulated with 1ug/mL of lipopolysaccharide (LPS) for 18h. The supernatant was employed for determination of tumor necrosis factor-alpha (TNF-α) and interleukin-1 (IL-1β) by enzyme immunoassay. The cells were also cultured for 30min to perform the extraction and determination of the nuclear activity of NF-kB., Results: The results showed increased endogenous activation of NF-kB in PBMC of the PE group compared with the NT and NP groups. We also observed increased production of TNF-α and IL-1β by non-stimulated PBMC in the PE group compared with NT and NP groups. A positive correlation between NF-kB activity and endogenous production of TNF-α (r=0.6509; p=0.0047) or IL-1 b (r=0.5106; p=0.0304) was observed in the PE group. Silibinin showed an anti-inflammatory activity by inhibiting the spontaneous and LPS-stimulated NF-kB activation as well as the production of inflammatory cytokines in all the groups studied., Conclusion: Patients with PE showed a greater activation of PBMC cells compared with NT women. Silibinin showed modulatory activity on the inflammatory response by downregulation of NF-kB activation as well as TNF-α and IL-10 production., Financial Support: FAPESP 2010/00776-0., (Copyright © 2012. Published by Elsevier B.V.)

Introduction: Hyperuricemia is a common finding in preeclamptic pregnancies and proteinuria, as well as hypertension are markers of preeclampsia. Production of anti-angiogenic proteins seems to be involved in the pathophysiology of hypertension and proteinuria in preeclampsia., Objectives: The purpose of this study was to evaluate whether there is an association between renal function and changes in serum levels of angiogenic factors in preeclamptic patients., Methods: Serum was obtained from 83 preeclamptic patients in the last trimester of pregnancy for determination of uric acid. Placental growth factor (PlGF), vascular endothelial growth factor (VEGF) and soluble form of vascular endothelial growth factor receptor (sVEGFR-1) were evaluated in serum by an enzyme immunoassay. Proteinuria was determined in a 24-h urine collection. The concentration of angiogenic factors was compared with serum uric acid levels (<6mg/dL vs ⩾6mg/dL) and with proteinuria levels (<2g vs ⩾2g). Statistical analysis was performed using non-parametric tests with significance level set at 5%., Results: In 40% of women with preeclampsia serum uric acid levels were ⩾6mg/dL, and proteinuria concentration ⩾2g was detected in 41% of patients. Positive correlation was observed between uric acid and proteinuria levels (r=0.7274; p<0.0001). Serum levels of PIGF were significantly lower in preeclamptic women with serum uric acid level ⩾6mg/dL compared with women with serum uric acid <6mg/dL (median 48.46 vs 117.32pg/mL). Significant difference between proteinuria ⩾2g and <2g was detected in relation to serum levels of PIGF (median 47.58 vs 114.24pg/mL), VEGF (median 25.35 vs 33.74pg/mL) and sVEGFR-1 (median 5386 vs 4605pg/mL)., Conclusion: Elevation in circulating uric acid as well as proteinuria in preeclamptic women is associated with an altered angiogenic balance, suggesting that angiogenic factors may be involved in kidney dysfunction., (Copyright © 2010. Published by Elsevier B.V.)

Introduction: Preeclampsia is a human pregnancy-specific syndrome characterized by the onset of hypertension and proteinuria. These manifestations may occur before the 34th week of gestation or from this period on, being denominated early-onset or late-onset preeclampsia respectively. The etiology of both disorders seems to differ qualitatively; therefore, different strategies of prevention and treatment must be studied., Objectives: The aim of the present study is to determine whether the plasma levels of heat-shock proteins Hsp60 and Hsp70 as well as specific antibodies anti-Hsp60 and anti-Hsp70 may differentiate early-onset from late-onset preeclampsia., Methods: We evaluated 175 pregnant women with PE (55 early-onset PE and 120 late-onset PE). Plasma was obtained from peripheral blood and Hsp60, Hsp70 as well as anti-Hsp60 and anti-Hsp70 antibody levels were determined by enzyme immunoassay. Uric acid levels were also determined in the plasma of patients. For statistical analyses, the Mann-Whitney U-test and the Spearman rank order correlation were applied with significance level set at 5%., Results: Hsp70 levels obtained from early-onset PE group were significantly higher than the late-onset PE women and showed positive correlation with uric acid (r=0.4547; p=0.0028). The Hsp60 production was similar in both groups. Our results also indicate that there was no significant difference of anti-Hsp60 and anti-Hsp70 antibody levels between women with early- and late-onset PE. However,these antibody levels were high,indicating a strong relationship with the production of HSP60 and Hsp70 protein., Conclusion: Association between levels of Hsp70 and uric acid in plasma of patients with early-onset PE seems to reflect the oxidative stress in this group of patients. This study provides evidence that Hsp70 determination may be utilized to assess the differentiation between early- and late-onset PE., Financial Support: FAPESP 2010/09241-2., (Copyright © 2012. Published by Elsevier B.V.)

Introduction: Monocytes from peripheral blood of pregnant women with preeclampsia are endogenously activated and secrete high levels of free radicals and inflammatory cytokines., Objectives: This study aimed at evaluating whether the inflammatory state of monocytes observed in preeclampsia is associated with the polarization of monocyte to M1 profile in peripheral blood, correlating the expression of surface receptors CD64, TLR2, TLR4, and CD163 and CD206 with cytokine production., Methods: We studied 90 pregnant women, 30 normotensive and 60 with preeclampsia, matched for gestational age. Peripheral blood monocytes obtained from normotensive pregnant or preeclamptic pregnant women were cultured for 18h, and the expression of surface receptors on M1 inflammatory monocyte subpopulation (TLR2, TLR4 and CD64) and M2 suppressor monocyte subpopulation (CD163 and CD206) were evaluated by flow cytometry, using specific monoclonal antibodies, labeled with fluorochromes. The values were expressed as ??the mean fluorescence intensity. Moreover, the production of proinflammatory cytokines associated with M1 profile (TNF-α, IL-12p70 and IL-23) and the anti-inflammatory cytokine associated with M2 profile (IL-10) were evaluated in the monocyte supernatant of culture by enzyme immunoassay. Results were analyzed using nonparametric tests with significance level set at 5%., Results: The expression of CD4 and TLR4 on monocyte surface, from women with preeclampsia was significantly higher, while the expression of CD163 and CD206 was significantly decreased compared with normotensive pregnant women, suggesting the predominance of monocyte M1 profile. Endogenous production of TNF-α, IL-12p70 and IL-23 by monocytes was increased, while synthesis of IL-10 was lower in women with preeclampsia compared with normotensive pregnant women. Positive correlations between TLR4 and CD64 (r=0.5849), TLR4 and TNF-α (r=0.5126) or TLR4 and IL-23 (r=0.8095), as well as between CD64 and TNF-α (r = 0.7133) or CD64 and IL-23 (r = 0.6051) were observed in the preeclamptic group. The results confirm the activated state of monocytes from women with preeclampsia by increased production of proinflammatory cytokines and the expression of receptors characteristic of the M1 subpopulation., Conclusion: This study provides evidence that monocytes from women with preeclampsia are classically activated and the systemic inflammatory environment may differentiate and polarize these cells to the M1 profile., Financial Support: CNPq, FAPESP 2009/11924-3 and 2010/20207-0., (Copyright © 2012. Published by Elsevier B.V.)

Introduction: Toll-like receptor (TLR)-4 and TLR-2 are involved in inflammatory response of monocytes. These cells are activated in pregnant women with preeclampsia (PE), and over-produce inflammatory cytokines. TLR4 may recognize endogenous ligands, the so-called danger signals released by damaged cells, leading to production of pro-inflammatory cytokines., Objectives: This study investigated TLR2 and TLR4 expression and cytokine production by monocytes from women with PE before and after stimulation with TLR ligands., Methods: Monocytes (5×10(5)cell/mL) were obtained from 32 preeclamptic (PE) and 20 normotensive (NT) pregnant women in the last trimester of pregnancy. TLR2 and TLR4 expression on monocyte surface was determined by flow cytometry in non-stimulated cells, and after 18h of culture with lipopysaccharide (LPS) and peptidoglycan (PG). TNF-α, IL-10 and IL-12p70 production by these cells stimulated or not with LPS or PG was evaluated by enzyme immunoassay. Results were analyzed by non-parametric tests with significance level set at 5%., Results: In the absence of stimulation, the basal TLR4 expression by monocytes detected by the median fluorescence intensity (MFI) was significantly higher in the PE group than in the NT group while no significant differences were observed between groups in relation to endogenous TLR2 expression. An increase in TLR4 MFIs was detected after monocytes from NT pregnant women were stimulated with LPS while TLR2 expression was increased after PG-stimulation. No alterations in TLR expression was detected after LPS or PG-stimulation in monocytes from patients with PE. Evaluation of endogenous cytokine levels in supernatant culture of monocytes showed higher concentrations of TNF-α and IL-12p70 in preeclamptic women in comparison with the NT group, whereas IL-10 values were significantly higher in NT pregnant women than in the PE group. In contrast, when monocytes were stimulated with the TLRs ligands LPS and PG, the release of TNF-α was significantly reduced, while IL-12p70 levels were significantly higher in women with PE compared to NT group. IL-10 production was similar in both groups studied., Conclusion: The basal up-regulation of TLR4 expression associated with endogenous high TNF-α and IL-12p70 production by monocytes from preeclamptic women confirms the activated profile of these cells by the disease process. These findings provide new insights into possible roles for TLRs in the pathogenesis of systemic inflammation detected in PE., Financial Support: FAPESP 2009/11924-3 and 2010/20207-0., (Copyright © 2012. Published by Elsevier B.V.)

Plants have contributed over the years to the discovery of various pharmacological products. Amongst the enormous diversity of herbs with remarkable medicinal use and further pharmacological potential, here in this report we evaluated pulp extracts from Eugenia dysenterica fruits and further identified the active principle involved in such laxative activity in rats. For protein isolation, fruits were macerated with an extraction solution following precipitation with (NH(4))(2)SO(4) (100%). After dialysis, the peptide was applied onto a reversed-phase semi-preparative HPLC column, and the major fraction was eluted with 26% and 66% acetonitrile. The evaluation of molecular masses by MALDI-TOF and Tris/Tricine SDS-PAGE of HPLC fractions showed the presence of a major peptide with approximately 7 kDa. The N-terminal amino acid peptide sequence was determined and showed no similarity to other proteins deposited in the Data Bank. Peptide from E. dysenterica was able to enhance rats' intestinal motility by approximately 20.8%, probably being responsible for laxative activity. Moreover, these proteins were non-toxic to mammals, as observed in histopathology and hemolytic analyses. In conclusion, results here reported indicate that, in the near future, proteins synthesized by E. dysenterica fruits could be utilized in the development of novel biotechnological pharmaceutics with laxative properties for use in chronic constipation and irritable bowel syndrome treatment., (Copyright 2010 Elsevier Inc. All rights reserved.)

The authors explained the initial experience of Department of Infectology of the Hospital Nacional de Odontología, in Buenos Aires. The work in this Service was initiated in September 1987 and, at this time, is the first in Argentina exclusively organized for dental treatment of AIDS's patients.