357 research outputs found
Magnetic liposomes containing calcium ferrite nanoparticles for breast cancer therapy
In this work, calcium ferrite nanoparticles were prepared and characterized. The structural and magnetic properties of the nanoparticles were evaluated by XRD, TEM and SQUID. The synthesized nanoparticles were either entrapped in liposomes, originating aqueous magnetoliposomes (AMLs), or covered with a lipid bilayer, forming solid magnetoliposomes (SMLs). Magnetoliposomes present average diameters around 150 nm, suitable for biomedical applications.
The magnetoliposomes were loaded with new potential anticancer drugs, thienopyridine derivatives, with a strong antitumor activity against breast cancer cells.This work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding of CF-UM-UP (UID/FIS/04650/2013) and of CQUM (UID/QUI/00686/2013). FCT, POPH-QREN and FSE are acknowledged for the PhD grants of A. R. O. Rodrigues (SFRH/BD/90949/2012) and V. A. Machado (SFRH/BD/77373/2011) and for financial support to MAP-Fis Joint Doctoral Programme.info:eu-repo/semantics/publishedVersio
Widening the Spectrum of TMPRSS6 Gene Pathogenic Variants Related with Hereditary Iron Deficiency
Iron-Refractory Iron-Deficiency Anemia (IRIDA) is a rare autosomal recessive hypochromic microcytic anemia derived from loss-of-function mutations in the TMPRSS6 gene, which encodes Matriptase-2, a negative regulator of hepcidin expression. IRIDA patients have high hepcidin levels that prevent iron absorption and recycling. Very few studies concerning this pathology have been carried out in the Portuguese population and its molecular basis is still largely unknown.
In this study, we aimed to identify genetic variants in TMPRSS6 in a sample of the Portuguese population with a hematological phenotype suggestive of iron deficiency. In addition, we intended to evaluate the performance of NGS for genetic screening of this large gene.
We studied 100 adults with anemia and/or microcytosis and/or hypochromia collected by the Portuguese National Health Examination Survey (INSEF). Other possible genetic causes for these abnormal phenotypes, namely α- and β-thalassemia, were discarded after HBA1, HBA2 and HBB genetic screening. The TMPRSS6 gene (18 coding regions, exon/intron boundaries and regulatory regions) was amplified in 3 long-PCR fragments that were screened by NGS using Nextera XT libraries in a MiSeq platform. The genetic variants found were validated by Sanger sequencing (transcript ENST00000676104.1).
Several known variants were identified along with two unreported mutations, c.1585T>C (p.Cys529Arg) and c.1580T>G (p.Phe527Cys). These novel mutations were classified as pathogenic by in silico analyses through Polyphen2, SIFT, and Missense3D. Moreover, Phyre2 software was used to produce a 3D structure of the mutated proteins, based on alignments with known protein structures, as there is no 3D model for Matriptase-2 on online databases. The two novel mutations were found in heterozygosity, explaining the mild abnormal hematological phenotypes and serum iron biomarkers presented by both patients. Functional studies should be performed to validate these findings.
Our results widened the spectrum of TMPRSS6 pathogenic variants underlying hereditary iron deficiency-related pathologies. In addition, NGS revealed to be an appropriate tool for TMPRSS6 genetic screening.Este trabalho é um sub-estudo do INSEF, desenvolvido no âmbito do Projeto Pré-definido do Programa Iniciativas em Saúde Pública, foi promovido pelo Instituto Nacional de Saúde Doutor Ricardo Jorge através do Departamento de Epidemiologia e beneficiou de apoio financeiro concedido pela Islândia, Liechtenstein e Noruega, através das EEA GrantsN/
Tradução e validação da Clinician Administered PTSD Scale (CAPS-CA-5) em crianças e adolescentes portugueses
Introduction: The aim of this study was to translate and validate into European Portuguese the CAPS-CA-5 (Clinician Administered PTSD Scale for Children and Adolescents), a semi-structured scale for the diagnosis of post-traumatic stress disorder in children and adolescents, according to the DSM-5 criteria. Material and Methods: This study was developed in three stages. In the first stage, the translation and back-translation of CAPS-CA-5 into European Portuguese was carried out. In the second stage, the version obtained in the previous step was subjected to a pre-test. In the third stage, the final version of CAPS-CA-5, the KIDCOPE questionnaires and the Depression, Anxiety and Stress Scale-Children were applied to 101 children who had experienced at least one potentially traumatic event. The children included in this study were between seven and 18 years old and had a follow-up period in a Child Psychiatry or Pediatrics Clinic in one of the three hospitals involved in this project of at least one month. Results: Regarding the confirmatory factor analysis, our results show that the CAPS-CA-5 is a suitable psychometric instrument to assess the diagnosis and symptoms severity of post-traumatic stress disorder according to DSM-5. Convergent validity was comparable to its original version. Although there were negative relationships with almost all of its clusters, these were not statistically significant when applied with the positive coping strategies of the KIDCOPE. The European Portuguese version of the CAPS-CA-5 showed a good internal consistency (Cronbach’s α for the total scale was 0.89). Conclusion: The European Portuguese version of CAPS-CA-5 has similar psychometric properties to its original versionIntrodução: O objetivo deste estudo foi traduzir e validar para português europeu a CAPS-CA-5 (Clinician Administered PTSD Scale for Children and Adolescents), uma escala semiestruturada para o diagnóstico de perturbação de stress pós-traumático em crianças e adolescentes, de acordo com os critérios do DSM-5. Material e Métodos: Este estudo foi desenvolvido em três etapas. Na primeira, foi realizada a tradução e contra-tradução da CAPS- -CA-5 para português europeu. Na segunda etapa, a versão obtida anteriormente foi submetida a um pré-teste. Na terceira etapa, a versão final da CAPS-CA-5, os questionários KIDCOPE e a Escala de Depressão, Ansiedade e Stresse - Crianças foram aplicados em 101 crianças que experienciaram pelo menos um evento potencialmente traumático. As crianças incluídas neste estudo tinham entre sete e 18 anos e tinham um período de acompanhamento em consulta de Psiquiatria Infantil ou Pediatria de pelo menos um mês, num dos três hospitais envolvidos neste projeto. Resultados: Em relação à análise fatorial confirmatória, os nossos resultados mostram que a CAPS-CA-5 é um instrumento psico-métrico adequado para avaliar o diagnóstico e a gravidade dos sintomas de perturbação de stresse pós-traumático de acordo com o DSM-5. A validade convergente foi comparável à versão original. Embora tenha havido relações negativas com quase todos os seus clusters, estas não foram estatisticamente significativas quando aplicadas com as estratégias de coping positivo do KIDCOPE. A versão em português europeu da CAPS-CA-5 apresentou boa consistência interna (α de Cronbach para a escala total foi de 0,89). Conclusão: A versão em português europeu do CAPS-CA-5 possui propriedades psicométricas semelhantes à sua versão originalinfo:eu-repo/semantics/publishedVersio
It takes two to remyelinate: A bioengineered platform to study astrocyte-oligodendrocyte crosstalk and potential therapeutic targets in remyelination
The loss of the myelin sheath insulating axons is the hallmark of demyelinating diseases. These pathologies often lead to irreversible neurological impairment and patient disability. No effective therapies are currently available to promote remyelination. Several elements contribute to the inadequacy of remyelination, thus understanding the intricacies of the cellular and signaling microenvironment of the remyelination niche might help us to devise better strategies to enhance remyelination. Here, using a new in vitro rapid myelinating artificial axon system based on engineered microfibres, we investigated how reactive astrocytes influence oligodendrocyte (OL) differentiation and myelination ability. This artificial axon culture system enables the effective uncoupling of molecular cues from the biophysical properties of the axons, allowing the detailed study of the astrocyte-OL crosstalk. Oligodendrocyte precursor cells (OPCs) were cultured on poly(trimethylene carbonate-co-ε-caprolactone) copolymer electrospun microfibres that served as surrogate axons. This platform was then combined with a previously established tissue engineered glial scar model of astrocytes embedded in 1 % (w/v) alginate matrices, in which astrocyte reactive phenotype was acquired using meningeal fibroblast conditioned medium. OPCs were shown to adhere to uncoated engineered microfibres and differentiate into myelinating OL. Reactive astrocytes were found to significantly impair OL differentiation ability, after six and eight days in a co-culture system. Differentiation impairment was seen to be correlated with astrocytic miRNA release through exosomes. We found significantly reduction on the expression of pro-myelinating miRNAs (miR-219 and miR-338) and an increase in anti-myelinating miRNA (miR-125a-3p) content between reactive and quiescent astrocytes. Additionally, we show that OPC differentiation inhibition could be reverted by rescuing the activated astrocytic phenotype with ibuprofen, a chemical inhibitor of the small rhoGTPase RhoA. Overall, these findings show that modulating astrocytic function might be an interesting therapeutic avenue for demyelinating diseases. The use of these engineered microfibres as an artificial axon culture system will enable the screening for potential therapeutic agents that promote OL differentiation and myelination while providing valuable insight on the myelination/remyelination processes
Yicathins B and C and analogues: total synthesis, lipophilicity and biological activities
Natural products had always be an important source of new hits and leads in drug discovery. The marine environment has been regarded as a significant souce of novel and exquisite bioactive compounds. Yicathins B and C are two marine derived xanthones that have shown antibacterial and antifungal activities. Herein, the total synthesis of these yicathins is reported for the first time as well as six novel analogues. As marine natural products tend to bear very lipophilic scaffolds, the lipophilicity of yicathins and its analogues was
evaluated using the classical octanol:water system and a biomimetic model based system. As the xanthonic nucleus is a â privileged structureâ , other biological activities were evaluated, namely antitumor and anti-inflammatory activities. An interesting anti-inflammatory activity was identified for yicathins analogues that paves the way for the design of dual activity (anti-infective and anti-inflammatory) marine inspired xanthones derivatives.This work was supported through national funds provided by FCT/MCTES - Foundation for Science and Technology from the Minister of Science, Technology and Higher Education (PIDDAC) and European Regional Development Fund (ERDF) through the COMPETE - Programa Operacional Factores de Competitividade (POFC) programme, under the projects PTDC/MAR-BIO/4694/2014 (reference POCI-01-0145-FEDER-016790; Project 3599 - Promover a ProducAo Cientifica e Desenvolvimento Tecnologico e a ConstituicAo de Redes Tematicas (3599-PPCDT)) and PTDC/SAU-PUB/28736/2017 (reference POCI-01-0145-FEDER- 028736) in the framework of the programme PT2020. D. R. P. L. is grateful for research grant PTDC/MAR-BIO/4694/2014-BI-2017-003. J. X. S. thanks the FCT PhD Programmes and Programa Operacional Capital Humano (POCH), specifically the BiotechHealth Programme (Doctoral Programme on Cellular and Molecular Biotechnology Applied to Health Sciences), reference PD/00016/2012; through the FCT and POCH for PhD grants (SFRH/BD/98105/2013 and SFRH/BD/116167/2016). The authors would like to thank Sara Cravo and Gisela Adriano for the technical support, the Centro de Apoio Cientifico e Tecnoloxico a Investigation (C.A.C.T.I., University of Vigo, Pontevedra, Spain) for HRMS analysis, the Centro de Materiais da Universidade do Porto (CEMUP, Porto, Portugal) for HRMS, and the Departamento de Quimica da Universidade de Aveiro (Portuguese NMR network) for the NMR analysis
Detecting and Characterising atmospheric gravity waves on Mars' atmosphere - Final results using data from OMEGA/Mars Express
We present the final results from the detection and characterisation of mesoscale waves on the lower clouds of Mars [1] using images from the Observatoire pour la Minéralogie, l’Eau, les Glaces et l’Activité (OMEGA) [2] onboard the European Mars Express (MEx) space mission [3]. We used image navigation and processing techniques based on contrast enhancement and geometrical projections to characterise morphological properties of the detected gravity waves (GW), such as horizontal wavelength or packet length. Our study covers 25 months of data spanning from Jan. 2004 to Jan. 2006, and from June to July 2007, corresponding to a one Martian year [MY26- MY27]. Out of 148 detected wave packets, we were able to characterise 61 across more than 4000 images covering a broad region of the Martian globe.
Our results reveal that waves exhibit an average horizontal wavelength of 23 km, which is consistent with previous observations [4,5]. We also extend the study by characterising their packet width, length and orientation. Taking advantage of the large dataset available from the OMEGA instrument, we also conducted a spatial and temporal investigation of the waves, namely their occurrence in specific local times and solar longitudes. Our characterisation showed a higher frequency of GW during daytime hours, particularly within the 13-15 LTST range. Concerning the solar longitude that is a measure of the Martian seasons, we noted that GW activity is prevalent during the winter season in both hemispheres, suggesting a relationship between seasonal variations and gravity wave generation, which was previously mentioned in the literature [6–8]. We will also present the preliminary results of GW using the HRSC instrument
Long‐term outcomes and molecular analysis of a large cohort of patients with 46,XY disorder of sex development due to partial gonadal dysgenesis
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145419/1/cen13717_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145419/2/cen13717.pd
Ancient and recent differences in the intrinsic susceptibility of Mycobacterium tuberculosis complex to pretomanid
OBJECTIVES: To develop a robust phenotypic antimicrobial susceptibility testing (AST) method with a correctly set breakpoint for pretomanid (Pa), the most recently approved anti-tuberculosis drug. METHODS: The Becton Dickinson Mycobacterial Growth Indicator Tube™ (MGIT) system was used at six laboratories to determine the MICs of a phylogenetically diverse collection of 356 Mycobacterium tuberculosis complex (MTBC) strains to establish the epidemiological cut-off value for pretomanid. MICs were correlated with WGS data to study the genetic basis of differences in the susceptibility to pretomanid. RESULTS: We observed ancient differences in the susceptibility to pretomanid among various members of MTBC. Most notably, lineage 1 of M. tuberculosis, which is estimated to account for 28% of tuberculosis cases globally, was less susceptible than lineages 2, 3, 4 and 7 of M. tuberculosis, resulting in a 99th percentile of 2 mg/L for lineage 1 compared with 0.5 mg/L for the remaining M. tuberculosis lineages. Moreover, we observed that higher MICs (≥8 mg/L), which probably confer resistance, had recently evolved independently in six different M. tuberculosis strains. Unlike the aforementioned ancient differences in susceptibility, these recent differences were likely caused by mutations in the known pretomanid resistance genes. CONCLUSIONS: In light of these findings, the provisional critical concentration of 1 mg/L for MGIT set by EMA must be re-evaluated. More broadly, these findings underline the importance of considering the global diversity of MTBC during clinical development of drugs and when defining breakpoints for AST
Predicting the Proteins of Angomonas deanei, Strigomonas culicis and Their Respective Endosymbionts Reveals New Aspects of the Trypanosomatidae Family
Endosymbiont-bearing trypanosomatids have been considered excellent models for the study of cell evolution because the host protozoan co-evolves with an intracellular bacterium in a mutualistic relationship. Such protozoa inhabit a single invertebrate host during their entire life cycle and exhibit special characteristics that group them in a particular phylogenetic cluster of the Trypanosomatidae family, thus classified as monoxenics. in an effort to better understand such symbiotic association, we used DNA pyrosequencing and a reference-guided assembly to generate reads that predicted 16,960 and 12,162 open reading frames (ORFs) in two symbiont-bearing trypanosomatids, Angomonas deanei (previously named as Crithidia deanei) and Strigomonas culicis (first known as Blastocrithidia culicis), respectively. Identification of each ORF was based primarily on TriTrypDB using tblastn, and each ORF was confirmed by employing getorf from EMBOSS and Newbler 2.6 when necessary. the monoxenic organisms revealed conserved housekeeping functions when compared to other trypanosomatids, especially compared with Leishmania major. However, major differences were found in ORFs corresponding to the cytoskeleton, the kinetoplast, and the paraflagellar structure. the monoxenic organisms also contain a large number of genes for cytosolic calpain-like and surface gp63 metalloproteases and a reduced number of compartmentalized cysteine proteases in comparison to other TriTryp organisms, reflecting adaptations to the presence of the symbiont. the assembled bacterial endosymbiont sequences exhibit a high A+T content with a total of 787 and 769 ORFs for the Angomonas deanei and Strigomonas culicis endosymbionts, respectively, and indicate that these organisms hold a common ancestor related to the Alcaligenaceae family. Importantly, both symbionts contain enzymes that complement essential host cell biosynthetic pathways, such as those for amino acid, lipid and purine/pyrimidine metabolism. These findings increase our understanding of the intricate symbiotic relationship between the bacterium and the trypanosomatid host and provide clues to better understand eukaryotic cell evolution.Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)ERC AdG SISYPHEUniv Fed Rio de Janeiro, Inst Biofis Carlos Chagas Filho, Lab Ultraestrutura Celular Hertha Meyer, BR-21941 Rio de Janeiro, BrazilUniv Fed Rio de Janeiro, Inst Biofis Carlos Chagas Filho, Lab Metab Macromol Firmino Torres de Castro, BR-21941 Rio de Janeiro, BrazilLab Bioinformat, Lab Nacl Computacao Cient, Rio de Janeiro, BrazilINRIA Grenoble Rhone Alpes, BAMBOO Team, Villeurbanne, FranceUniv Lyon 1, CNRS, UMR5558, Lab Biometrie & Biol Evolut, F-69622 Villeurbanne, FranceUniv Estadual Campinas, Inst Biol, Dept Genet Evolucao & Bioagentes, São Paulo, BrazilUniv São Paulo, Fac Ciencias Farmaceut Ribeirao Preto, Dept Ciencias Farmaceut, São Paulo, BrazilLab Nacl Ciencia & Tecnol Bioetano, São Paulo, BrazilUniv Fed Minas Gerais, Inst Ciencias Biol, Dept Bioquim & Imunol, Belo Horizonte, MG, BrazilUniv Fed Goias, Inst Ciencias Biol, Mol Biol Lab, Goiania, Go, BrazilFundacao Oswaldo Cruz, Inst Carlos Chagas, Lab Biol Mol Tripanossomatideos, Curitiba, Parana, BrazilFundacao Oswaldo Cruz, Inst Carlos Chagas, Lab Genom Func, Curitiba, Parana, BrazilUniv Estadual Campinas, Ctr Pluridisciplinar Pesquisas Quim Biol & Agr, São Paulo, BrazilUniv Fed Minas Gerais, Inst Ciencias Biol, Dept Parasitol, Belo Horizonte, MG, BrazilUniv Fed Santa Catarina, Dept Microbiol Imunol & Parasitol, Ctr Ciencias Biol, Lab Protozool & Bioinformat, Florianopolis, SC, BrazilUniv Fed Vicosa, Dept Bioquim & Biol Mol, Ctr Ciencias Biol & Saude, Vicosa, MG, BrazilInst Butantan, Lab Especial Ciclo Celular, São Paulo, BrazilUniv São Paulo, Dept Biol, Fac Filosofia Ciencias & Letras Ribeirao Preto, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, São Paulo, BrazilWeb of Scienc
Cohort profile: the 100 million Brazilian cohort
The creation of The 100 Million Brazilian Cohort was motivated by the availability of high quality but dispersed social and health databases in Brazil and the need to integrate data and evaluate the impact of policies aiming to improve the social determinants of health (e.g. social protection policies) on health outcomes, overall and in subgroups of interest in a dynamic cohort.
• The baseline of The 100 Million Brazilian Cohort comprises 131 697 800 low-income individuals in 35 358 415 families from 2011 to 2018. The Cohort population is mostly composed of children and young adults, with a higher proportion of females than the general Brazilian population, who identify themselves as Brown and live in the urban area of the country.
• Exposure to social protection and the follow-up of individuals are obtained through: (i) deterministic linkage using the Social Identification Number (NIS) to link the Cohort baseline to social protection programmes and to periodically renewed socioeconomic information in Cadatro U ́ nico datasets; and/or (ii) non-deterministic linkage using the CIDACS-RL non-deterministic linkage tool, to link the Cohort baseline to administrative health care datasets such as mortality (Mortality Information System, SIM), disease notification (Information System for Notifiable Diseases, SINAN), birth information (Live Birth Information System, SINASC) and nutrition status (Food and Nutrition Surveillance System, SISVAN).
• So far, studies have used The 100 Million Brazilian Cohort to investigate the socioeconomic and demographic determinants of leprosy, leprosy treatment outcomes and low birthweight and to evaluate the impact of the Bolsa Familia Programme (BFP) on leprosy and child mortality. Other studies are now being conducted that are of utmost relevance to the health inequalities of Brazil and many low- and middle-income countries, and many research opportunities are being opened up with the linkage of a range of health outcomes
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