1,327 research outputs found
MASCOT ON-BOARD COMPUTER BASED ON SPACEWIRE LINKS
The general concept of the “Mobile Asteroid Surface Scout” (MASCOT) is to provide
a small landing system intended to be deployed from a supporting main spacecraft. It
is specifically designed to be compatible with JAXA’s Hayabusa 2 (HY2, scheduled
for launch in 2014) mission design and the environment given by the target asteroid
1999JU3. The design foresees an OBC for gathering, processing, compressing and
storing of the scientific payload and the housekeeping data and to run system and
subsystem tasks
Grupos de pesquisa em enfermagem no Brasil: comparação dos perfis de 2006 e 2016
RESUMO Objetivos Comparar o perfil dos grupos de pesquisa em Enfermagem cadastrados no Diretório do CNPq em 2006 e 2016. Métodos Estudo descritivo documental. A coleta de dados aconteceu em 2006 e 2016 a partir de consulta parametrizada com o termo Enfermagem no Diretório dos Grupos de Pesquisa, na página online do CNPq, sendo realizada a análise descritiva. Os dados foram organizados em planilha do Excel. Resultados O número de Grupos de Pesquisa aumentou de 251 em 2006 para 617 em 2016, com incremento no número de participantes. Houve redução do número de grupos sem estudantes, embora 22% permaneçam sem participação de alunos de graduação. Conclusões Os grupos de pesquisa em Enfermagem refletem avanços estruturais e políticos na geração de ciência, tecnologia e inovação da área, entretanto ainda deve ser incentivada a participação de alunos de graduação e pesquisadores estrangeiros, bem como a ampliação de recursos tecnológicos e das parcerias interinstitucionais
Entrapment ability and release profile of corticosteroids from starch-based microparticles
We previously described the synthesis of starchbased microparticles that were shown to be bioactive (when combined with Bioactive Glass 45S5) and noncytotoxic. To
further assess their potential for biomedical applications such as controlled release, three corticosteroids with a similar basic structure—dexamethasone (DEX), 16-methylprednisonole
(MP), and 16-methylprednisolone acetate
(MPA) - were used as models for the entrapment and release of bioactive agents. DEX, MP, and MPA were entrapped
into starch-based microparticles at 10% wt/wt of the starch-based polymer and the loading efficiencies, as well as the release profiles, were evaluated. Differences were
found for the loading efficiencies of the three corticosteroids, with DEX and MPA being the most successfully loaded (82 and 84%, respectively), followed by MP (51%). These differences might be explained based on the differential distribution of the molecules within the matrix of the microparticles.
Furthermore, a differential burst release was observed in the first 24 h for all corticosteroids with DEX and MP being
more pronounced (around 25%), whereas only 12% of MPA was released during the same time period. Whereas the water uptake profile can account for this first stage burst
release, the subsequent slower release stage was mainly attributed to degradation of the microparticle network. Differences
in the release profiles can be explained based on the structure of the molecule, because MPA, a more bulky and hydrophobic molecule, is released at a slower rate compared
with DEX and MP. In this work, it is shown that these carriers were able to sustain a controlled release of the entrapped corticosteroids over 30 days, which confirms the potential of these systems to be used as carriers for the delivery of bioactive agents
State of the Art and Future Challenges in Multiple Sclerosis Research and Medical Management: An Insight into the 5th International Porto Congress of Multiple Sclerosis
The 5th International Porto Congress of Multiple Sclerosis took place between the 14th and 16th of February 2019 in Porto, Portugal. Its intensive programme covered a wide-range of themes—including many of the hot topics, challenges, pitfalls and yet unmet needs in the field of multiple sclerosis (MS)—led by a number of well-acknowledged world experts. This meeting review summarizes the talks that took place during the congress, which focussed on issues in MS as diverse as the development and challenges of progressive MS, epidemiology, differential diagnosis, medical management, molecular research and imaging tools
Prevalence of antimicrobial resistance in enteric Escherichia coli from domestic pets and assessment of associated risk markers using a generalized linear mixed model
Antimicrobial resistance (AMR) is a growing global public health problem, which is caused by the use of antimicrobials in both human and animal medical practice. The objectives of the present cross-sectional study were as follows: (1) to determine the prevalence of resistance in Escherichia coli isolated from the feces of pets from the Porto region of Portugal against 19 antimicrobial agents and (2) to assess the individual, clinical and environmental characteristics associated with each pet as risk markers for the AMR of the E. coli isolates.
From September 2009 to May 2012, rectal swabs were collected from pets selected using a systematic random procedure from the ordinary population of animals attending the Veterinary Hospital of Porto University. A total of 78 dogs and 22 cats were sampled with the objective of isolating E. coli. The animals’ owners, who allowed the collection of fecal samples from their pets, answered a questionnaire to collect information about the markers that could influence the AMR of the enteric E. coli. Chromocult tryptone bile X-glucuronide agar was used for E. coli isolation, and the disk diffusion method was used to determine the antimicrobial susceptibility. The data were analyzed using a multilevel, univariable and multivariable generalized linear mixed model (GLMM). Several (49.7%) of the 396 isolates obtained in this study were multidrug-resistant. The E. coli isolates exhibited resistance to the antimicrobial agent's ampicillin (51.3%), cephalothin (46.7%), tetracycline (45.2%) and streptomycin (43.4%). Previous quinolone treatment was the main risk marker for the presence of AMR for 12 (ampicillin, cephalothin, ceftazidime, cefotaxime, nalidixic acid, ciprofloxacin, gentamicin, tetracycline, streptomycin, chloramphenicol, trimethoprim–sulfamethoxazole and aztreonam) of the 15 antimicrobials assessed. Coprophagic habits were also positively associated with an increased risk of AMR for six drugs, ampicillin, amoxicillin–clavulanic acid, cephamycin, ciprofloxacin, streptomycin, and trimethoprim–sulfamethoxazole.
In summary, pets with a record of one or more previous quinolone treatments and exhibiting coprophagic habits were at an increased risk of harboring multidrug-resistant E. coli strains in their feces compared to pets without these characteristics. AMR is a serious global problem, and assessing the risk markers for the presence of drug-resistant bacteria in pets, a very close source of resistance determinants to humans, is essential for the implementation of safe handling procedures for companion animals and for the prudent selection of antimicrobial compounds in veterinary practice
Polimorfismo e esteroides androgênicos anabólicos: uma revisão integrativa / Polymorphism and anabolic androgenic steroids: an integrative review
Esteroides androgênicos anabólicos (EAAs) são substâncias relacionadas a testosterona que estimularão o crescimento dos tecidos corporais e aumento da performance em exercícios. O uso desses esteroides por frequentadores de academia e fisiculturistas tem se tornado um problema de saúde pública. Determinados polimorfismos genéticos (SNPs), causam alterações no metabolismo destas substâncias podendo agravar os efeitos colaterais. Diante do exposto, o objetivo desta pesquisa é descrever a influência dos SNPs bem como a potencialização dos efeitos colaterais após uso contínuo de EAAs. Este estudo consiste em uma revisão narrativa realizada entre os meses de março e abril de 2019 utilizando-se artigos publicados entre os anos de 2008 e 2019 obtidos a partir do banco de dados PubMed utilizando os descritores obtidos através do DeCs: “Polymorphism” AND “Anabolic Agents”. Foram incluídos artigos que fizessem relação direta com o tema proposto e apresentasse resultados em humanos. Artigos que não abordavam a temática central desta pesquisa foram excluídos. Foram encontrados 29 artigos, após leitura prévia apenas 11 foram selecionados. Dentre os resultados obtidos, o polimorfismo no gene UGT2B17 foi o mais citado, o mesmo causa uma diminuição da excreção de testosterona pela urina, permitindo uma maior concentração no sangue podendo assim agravar os efeitos colaterais. Além deste, polimorfismos nos genes ATP8B1/ABCB11, CYP17 e receptores ?-adrenérgicos também foram citados como responsáveis por alterações metabólicas destas substâncias. Diante do exposto, este estudo possibilitou identificar quais são os polimorfismos relatados com maior frequência na literatura quando associado a EAAs. De toda forma, faz-se necessário novos estudos com o intuito de elucidar de forma clara quais prejuízos o uso indiscriminado destas substâncias pode trazer ao indivíduo em longo praz
Bone marrow mesenchymal stem cells' secretome exerts neuroprotective effects in a Parkinson's disease rat model
Parkinson's disease (PD) is characterized by a selective loss of dopamine (DA) neurons in the human midbrain causing motor dysfunctions. The exact mechanism behind dopaminergic cell death is still not completely understood and, so far, no cure or neuroprotective treatment for PD is available. Recent studies have brought attention to the variety of bioactive molecules produced by mesenchymal stem cells (MSCs), generally referred to as the secretome. Herein, we evaluated whether human MSCs-bone marrow derived (hBMSCs) secretome would be beneficial in a PD pre-clinical model, when compared directly with cell transplantation of hBMSCs alone. We used a 6-hydroxydpomanie (6-OHDA) rat PD model, and motor behavior was evaluated at different time points after treatments (1, 4, and 7 weeks). The impact of the treatments in the recovery of DA neurons was estimated by determining TH-positive neuronal densities in the substantia nigra and fibers in the striatum, respectively, at the end of the behavioral characterization. Furthermore, we determined the effect of the hBMSCs secretome on the neuronal survival of human neural progenitors in vitro, and characterized the secretome through proteomic-based approaches. This work demonstrates that the injection of hBMSCs secretome led to the rescue of DA neurons, when compared to transplantation of hBMSCs themselves, which can explain the recovery of secretome-injected animals' behavioral performance in the staircase test. Moreover, we observed that hBMSCs secretome induces higher levels of in vitro neuronal differentiation. Finally, the proteomic analysis revealed that hBMSCs secrete important exosome-related molecules, such as those related with the ubiquitin-proteasome and histone systems. Overall, this work provided important insights on the potential use of hBMSCs secretome as a therapeutic tool for PD, and further confirms the importance of the secreted molecules rather than the transplantation of hBMSCs for the observed positive effects. These could be likely through normalization of defective processes in PD, namely proteostasis or altered gene transcription, which lately can lead to neuroprotective effects.Portuguese Foundation for Science and Technology: IF Development Grant (IF/00111/2013) to AS, Post-Doctoral Fellowship to FT (SFRH/BPD/118408/2016) and Doctoral Fellowship to BM-P (SFRH/BD/120124/2016); Canada Research Chair in Biomedical Engineering (LAB). This work was funded by FEDER, through the Competitiveness Internationalization Operational Programme (POCI), and by National funds, through the Foundation for Science and Technology (FCT), under the scope of the projects: POCI-01-0145-FEDER-029751; POCI-01-0145-FEDER-007038; POCI-01-0145-FEDER-032619; POCI-01-0145-FEDER-016428 (ref.: SAICTPAC/0010/2015), POCI-01-0145-FEDER-016795 (ref.: PTDC/NEU-SCC/7051/2014), POCI-01-0145-FEDER-029311 (ref.: PTDC/BTM-TEC/29311/2017), POCI-01-0145-FEDER-30943 (ref.: PTDC/MEC-PSQ/30943/2017) and PTDC/MED-NEU/27946/2017; UID/NEU/04539/2013 and POCI-01-0145-FEDER-007440. This article has also been developed under the scope of the project NORTE-01-0145-FEDER-000023, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER). Co-funded by the Programa Operacional Factores de Competitividade (QREN) and by The National Mass Spectrometry Network under the contract POCI-01-0145-FEDER-402-022125 (ref.: ROTEIRO/0028/2013
Exact equivalence at cyclic steady state between isothermal diffusion and linear driving force models for linear adsorption systems
Genome of the Avirulent Human-Infective Trypanosome—Trypanosoma rangeli
Background: Trypanosoma rangeli is a hemoflagellate protozoan parasite infecting humans and other wild and domestic mammals across Central and South America. It does not cause human disease, but it can be mistaken for the etiologic agent of Chagas disease, Trypanosoma cruzi. We have sequenced the T. rangeli genome to provide new tools for elucidating the distinct and intriguing biology of this species and the key pathways related to interaction with its arthropod and mammalian hosts. Methodology/Principal Findings: The T. rangeli haploid genome is ,24 Mb in length, and is the smallest and least repetitive trypanosomatid genome sequenced thus far. This parasite genome has shorter subtelomeric sequences compared to those of T. cruzi and T. brucei; displays intraspecific karyotype variability and lacks minichromosomes. Of the predicted 7,613 protein coding sequences, functional annotations could be determined for 2,415, while 5,043 are hypothetical proteins, some with evidence of protein expression. 7,101 genes (93%) are shared with other trypanosomatids that infect humans. An ortholog of the dcl2 gene involved in the T. brucei RNAi pathway was found in T. rangeli, but the RNAi machinery is non-functional since the other genes in this pathway are pseudogenized. T. rangeli is highly susceptible to oxidative stress, a phenotype that may be explained by a smaller number of anti-oxidant defense enzymes and heatshock proteins. Conclusions/Significance: Phylogenetic comparison of nuclear and mitochondrial genes indicates that T. rangeli and T. cruzi are equidistant from T. brucei. In addition to revealing new aspects of trypanosome co-evolution within the vertebrate and invertebrate hosts, comparative genomic analysis with pathogenic trypanosomatids provides valuable new information that can be further explored with the aim of developing better diagnostic tools and/or therapeutic targets
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