268 research outputs found

    COMPUTATIONAL MODELLING OF CONTAMINANT TRANSPORT UNDER NONLINEAR BIODEGRADATION AND PHYSICAL SORPTION PROCESSES IN A SATURATED POROUS MEDIUM

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    Abstract The aim of this work is to develop a computational modelling for a multiple species contaminant transport under nonlinear biodegradation and physical sorption processes in a saturated porous medium, which characterizes a scenario of subsurface contamination by organic contaminants. Sorption in nonlinear equilibrium and non-equilibrium conditions are incorporated upon the model setting as Freundlich type. Moreover, aerobic biodegradation is modelled through the multiplicative Monod kinetic. Mathematically, the problem is given by a nonlinear advection-diffusion-reaction partial differential system coupled by the reaction terms, associated with the biodegradation process. A new operator-splitting approach is proposed for treating in a sequential fashion the convectivediffusive and reactive terms. A predictor-multi corrector algorithm with Newton-Raphson and stabilized finite element (SUPG) methods are used in the time and spatial discretizations, respectively. Numerical results illustrate the good applicability and the effectiveness of the present approach, corroborating the well-known observation that to better predict contamination scenarios the nonlinear physical and biological processes should be inserted in the model

    Functional hybrid nanoemulsions for sumatriptan intranasal delivery

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    In recent years, advanced nanohybrid materials processed as pharmaceuticals have proved to be very advantageous. Triptans, such as the commercially available intranasal sumatriptan (SMT), are drugs employed in the treatment of painful migraine symptoms. However, SMT effectiveness by the intranasal route is limited by its high hydrophilicity and poor mucoadhesion. Therefore, we designed hybrid nanoemulsions (NE) composed of copaiba oil as the organic component plus biopolymers (xanthan, pectin, alginate) solubilized in the continuous aqueous phase, aiming at the intranasal release of SMT (2% w/v). Firstly, drug-biopolymer complexes were optimized in order to decrease the hydrophilicity of SMT. The resultant complexes were further encapsulated in copaiba oil-based nanoparticles, forming NE formulations. Characterization by FTIR-ATR, DSC, and TEM techniques exposed details of the molecular arrangement of the hybrid systems. Long-term stability of the hybrid NE at 25°C was confirmed over a year, regarding size (~ 120 nm), polydispersity (~ 0.2), zeta potential (~ −25 mV), and nanoparticle concentration (~ 2.1014 particles/mL). SMT encapsulation efficiency in the formulations ranged between 41–69%, extending the in vitro release time of SMT from 5 h (free drug) to more than 24 h. The alginate-based NE was selected as the most desirable system and its in vivo nanotoxicity was evaluated in a zebrafish model. Hybrid NE treatment did not affect spontaneous movement or induce morphological changes in zebrafish larvae, and there was no evidence of mortality or cardiotoxicity after 48 h of treatment. With these results, we propose alginate-based nanoemulsions as a potential treatment for migraine pain.Fil: Ribeiro, Lígia N. M.. Universidade Estadual de Campinas; BrasilFil: Rodrigues da Silva, Gustavo H.. Universidade Estadual de Campinas; BrasilFil: Couto, Verônica M.. Universidade Estadual de Campinas; BrasilFil: Castro, Simone R.. Universidade Estadual de Campinas; BrasilFil: Breitkreitz, Márcia C.. Universidade Estadual de Campinas; BrasilFil: Martinez, Carolina Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; Argentina. Universidad Nacional de Quilmes; ArgentinaFil: Igartúa, Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes; ArgentinaFil: Prieto, Maria Jimena. Universidad Nacional de Quilmes; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: de Paula, Eneida. Universidade Estadual de Campinas; Brasi

    Hemoglobinopatias no Distrito Federal, Brasil

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    Em uma amostra de 3137 pessoas, residentes no Distrito Federal, foram detectadas as seguintes hemoglobinas: em 3009(95,92%) HbAA; em 91 (2,90%) HbAS; em 20(0,64%) HbAC; em 8 (0,26%) talassemia beta minor; em 5(0,16%) HbAJ alfa; em 3 (0,09%) HbAM e em 1 (0,03%) talassemia major associada com HbAS. A HbAS têm as seguintes freqüências, quanto ao grupo racial: branco - 1,84%; mulato claro 2,55%; mulato médio-3,68%; mulato escuro - 6,80%; negro -10,43% e mestiço de índio -3,85%.The hemoglobins of 3137 persons from the Federal District, Brazil was studied. The identified types of hemoglobins were: HbAA (3009 - 95,92%); HbAS (91 - 2,90%); HbAC (20 - 0,64%) beta thalassemia minor (8 - 0,26%); HbAJ alpha (5 - 0,16%); HbAM (3 - 0,09%) and beta thalassemia major/HbS (1 - 0,03%). The frequencies of sickle cell trait (HbAS) of each racial class were: white (1,84%); light mulatto (2,55%); medium mulatto (3,68%); dark mulatto(6,80%), negro (10,43%)and indian mestizo (3,85%)

    Decrease in APP and CP mRNA expression in Alzheimer’s disease patients suggests impairment of cellular iron export in this dementia

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    Recentemente tem-se assistido a um acumular de evidência sugerindo a implicação de uma desregulação do metabolismo do ferro (Fe) na fisiopatologia da doença de Alzheimer (DA). Neste trabalho, pretendemos esclarecer melhor os mecanismos moleculares subjacentes à homeostasia deste metal na DA, particularmente ao nível do efluxo celular. Assim, mediu-se em células mononucleares do sangue periférico de 73 doentes com DA e 74 controlos a expressão de genes diretamente envolvidos na regulação e exportação celular de Fe, utilizando a técnica de PCR quantitativo. Os resultados mostraram uma diminuição significativa na expressão dos genes aconitase (ACO1; P=0,007); ceruloplasmina (CP; P<0,001) e proteína precursora de beta amilóide (APP; P=0,006) em doentes com DA comparativamente com os voluntários saudáveis. Estas observações apontam para uma diminuição significativa da expressão dos genes associados com a exportação de Fe celular mediada pela ferroportina na DA. Assim, o presente estudo reforça resultados anteriores que mostram alterações no metabolismo do Fe e podem estar na origem da retenção intracelular deste metal e aumento de stress oxidativo caraterísticos desta patologia.A dysregulation of iron (Fe) metabolism in Alzheimer’s disease (AD) has been suggested previously. Herein, we intended to further clarify the molecular mechanisms underlying Fe homeostasis in AD particularly at the level of cellular iron efflux. Thus, the expression of specific Fe metabolism-related genes directly involved in Fe regulation and export was assessed by quantitative PCR in peripheral blood mononuclear cells (PBMCs) from 73 AD patients and 74 controls. A significant decrease in the expression of aconitase 1 (ACO1; P=0.007); ceruloplasmin (CP; P<0.001) and amyloid peptide precursor (APP; P=0.006) genes was fund in AD patients compared with healthy volunteers. These observations point out to a significant downregulation of the expression of genes associated with ferroportin-mediated cellular Fe export in PBMCs from AD patients. The present findings support previous studies suggesting impairment of Fe homeostasis in AD, which may lead to cellular Fe retention and oxidative stress, a typical feature of this disease

    Processing of Apeiba tibourbou Aubl. extract via spray drying

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    The effects of drying air inlet temperature (IT) and concentration of Aerosil® 200 (CA) on several properties of spray-dried Apeiba tibourbou extracts were investigated following a 32 full factorial design. Powder recovery varied from 9.83 to 46.95% and dried products showed moisture contents below 7%. Although the spray-dried products lost some of their polyphenols, they still present excellent antioxidant activity, opening perspectives for its use to medicinal purpose. CA exerted a key role on the properties of spray-dried extracts, while IT did not present a significative influence. Aerosil® 200 proved to be an interesting alternative as an excipient for the drying of the herbal extract, even at intermediate concentrations such as 15%. The best combination of conditions to use for obtaining dry A. tibourbou extracts with adequate physicochemical and functional properties involves an IT of 100 ºC and a CA of 15%.Colegio de Farmacéuticos de la Provincia de Buenos Aire

    Validated HPLC-PDA method for rosmarinic acid quantification in Rosemary

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    A fast and simple HPLC-PDA method for rosmarinic acid quantification in Rosemary leaves powder was validated. The analyses were performed using a C18 column in isocratic conditions and detection at 254 nm. Performing the system suitability tests, the method showed to be capable of providing data of acceptable quality. Results showed that the method was selective, linear for concentration ranges between 2.5-50 μg.mL–1 , sensitive, precise, accurate and robust. The main advantages of the method were the simplicity and promptness of sample analysis, as well as equipment convenience. These results allowed us to conclude that it can be successfully applied on the routinely quality control of Rosemary phytopharmaceuticals inputs.Colegio de Farmacéuticos de la Provincia de Buenos Aire

    Pediatric tuberculosis in the metropolitan area of Rio de Janeiro

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    Aim: To evaluate the clinical characteristics, diagnostic approach, and treatment outcomes of tuberculosis (TB) in children living in a high-burden metropolitan area. Methods: This was a retrospective study, based on a medical chart review, involving children under 15 years old treated for TB between 2007 and 2016, in four primary health units (PHU) and three reference centers (RC) in five cities of Rio de Janeiro metropolitan area. Factors associated with TB treatment setting, microbiological diagnosis, and treatment outcomes were evaluated. Results: A total of 544 children were enrolled; 71% were treated in PHU, 36% were under 5 years old, and 72% had pulmonary TB (PTB). The HIV prevalence was 10% (31/322). Fifty-three percent had at least one microbiological test for TB, 68% of them (196/287) had TB confirmed. Among 222 children with previous TB contact, information on LTBI was available for 78 (35%), and only 17% (13/78) were treated. Extrapulmonary TB (56% vs 32%), microbiologically confirmed TB (77% vs 60%), and HIV positivity (18.5% vs 4.0%) were significantly more frequent in RC. Treatment in RC (odds ratio (OR) 3.08, 95% confidence interval (CI) 1.74–5.44) and PTB (OR 2.47, 95% CI 1.34–4.56) were independently associated with a microbiological diagnosis of TB. The treatment success rate was 85%. In the logistic regression analysis, HIV-infected children had a 2.5-fold higher risk of an unfavorable outcome (OR 2.53, 95% CI 1.0–6.38; p = 0.05). Conclusions: Opportunities for TB prevention and early TB treatment are missed due to suboptimal close contact screening. Microbiological diagnosis of TB and drug susceptibility testing in children should be made available through more sensitive and accessible tests

    Improving a Synechocystis-based photoautotrophic chassis through systematic genome mapping and validation of neutral sites

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    [EN] The use of microorganisms as cell factories frequently requires extensive molecular manipulation. Therefore, the identification of genomic neutral sites for the stable integration of ectopic DNA is required to ensure a successful outcome. Herewe describe the genome mapping and validation of five neutral sites in the chromosome of Synechocystis sp. PCC 6803, foreseeing the use of this cyanobacterium as a photoautotrophic chassis. To evaluate the neutrality of these loci, insertion/deletion mutants were produced, and to assess their functionality, a synthetic green fluorescent reporter module was introduced. The constructed integrative vectors include a BioBrick-compatible multiple cloning site insulated by transcription terminators, constituting robust cloning interfaces for synthetic biology approaches. Moreover, Synechocystis mutants (chassis) ready to receive purpose-built synthetic modules/circuits are also available. This work presents a systematic approach to map and validate chromosomal neutral sites in cyanobacteria, and that can be extended to other organisms.This work was supported by the European Commission through the Seventh Framework Programme, FP7-ENERGY-2012-1-2STAGE-308518 (CyanoFactory), from EU FP6-NEST-2005-Path-SYN project BioModularH2 (contract no. 043340) and from National Funds through Fundacao para a Ciencia e a Tecnologia (FCT) (grants SFRH/BD/36378/2007 to F.P., SFRH/BPD/64095/2009 to C.C.P., SFRH/BPD/74894/2010 to P.O.). We also acknowledge the Engineering and Physical Sciences Research Council (EPSRC) for funding (EP/E036252/1) and The University of Sheffield for Scholarship funding. Funding to pay the Open Access publication charges for this article was provided by the European Commission through the Seventh Framework Programme, FP7-ENERGY-2012-1-2STAGE-308518 (CyanoFactory).Pinto, F.; Pacheco, CC.; Oliveira, P.; Montagud, A.; Landels, A.; Couto, N.; Wright, PC.... (2015). Improving a Synechocystis-based photoautotrophic chassis through systematic genome mapping and validation of neutral sites. DNA Research. 22(6):425-437. https://doi.org/10.1093/dnares/dsv024S42543722
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