Microencapsulation Technology: A Powerful Tool for Integrating Expansion and Cryopreservation of Human Embryonic Stem Cells

The successful implementation of human embryonic stem cells (hESCs)-based technologies requires the production of relevant numbers of well-characterized cells and their efficient long-term storage. In this study, cells were microencapsulated in alginate to develop an integrated bioprocess for expansion and cryopreservation of pluripotent hESCs. Different three-dimensional (3D) culture strategies were evaluated and compared, specifically, microencapsulation of hESCs as: i) single cells, ii) aggregates and iii) immobilized on microcarriers. In order to establish a scalable bioprocess, hESC-microcapsules were cultured in stirred tank bioreactors

Combining Hypoxia and Bioreactor Hydrodynamics Boosts Induced Pluripotent Stem Cell Differentiation Towards Cardiomyocytes

Cardiomyocytes (CMs) derived from induced pluripotent stem cells (iPSCs) hold great promise for patient-specific disease modeling, drug screening and cell therapy. However, existing protocols for CM differentiation of iPSCs besides being highly dependent on the application of expensive growth factors show low reproducibility and scalability. The aim of this work was to develop a robust and scalable strategy for mass production of iPSC-derived CMs by designing a bioreactor protocol that ensures a hypoxic and mechanical environment. Murine iPSCs were cultivated as aggregates in either stirred tank or WAVE bioreactors. The effect of dissolved oxygen and mechanical forces, promoted by different hydrodynamic environments, on CM differentiation was evaluated. Combining a hypoxia culture (4 % O(2) tension) with an intermittent agitation profile in stirred tank bioreactors resulted in an improvement of about 1000-fold in CM yields when compared to normoxic (20 % O(2) tension) and continuously agitated cultures. Additionally, we showed for the first time that wave-induced agitation enables the differentiation of iPSCs towards CMs at faster kinetics and with higher yields (60 CMs/input iPSC). In an 11-day differentiation protocol, clinically relevant numbers of CMs (2.3 × 10(9) CMs/1 L) were produced, and CMs exhibited typical cardiac sarcomeric structures, calcium transients, electrophysiological profiles and drug responsiveness. This work describes significant advances towards scalable cardiomyocyte differentiation of murine iPSC, paving the way for the implementation of this strategy for mass production of their human counterparts and their use for cardiac repair and cardiovascular research. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s12015-014-9533-0) contains supplementary material, which is available to authorized users

Correcting for Superficial Bias in 7T Gradient Echo fMRI

The arrival of submillimeter ultra high-field fMRI makes it possible to compare activation profiles across cortical layers. However, the blood oxygenation level dependent (BOLD) signal measured by gradient echo (GE) fMRI is biased toward superficial layers of the cortex, which is a serious confound for laminar analysis. Several univariate and multivariate analysis methods have been proposed to correct this bias. We compare these methods using computational simulations of 7T fMRI data from regions of interest (ROI) during a visual attention paradigm. We also tested the methods on a pilot dataset of human 7T fMRI data. The simulations show that two methods–the ratio of ROI means across conditions and a novel application of Deming regression–offer the most robust correction for superficial bias. Deming regression has the additional advantage that it does not require that the conditions differ in their mean activation over voxels within an ROI. When applied to the pilot dataset, we observed strikingly different layer profiles when different attention metrics were used, but were unable to discern any differences in laminar attention across layers when Deming regression or ROI ratio was applied. Our simulations demonstrates that accurate correction of superficial bias is crucial to avoid drawing erroneous conclusions from laminar analyses of GE fMRI data, and this is affirmed by the results from our pilot 7T fMRI data

Risk-Benefit Assessment of Cereal-Based Foods Consumed by Portuguese Children Aged 6 to 36 Months-A Case Study under the RiskBenefit4EU Project

This article belongs to the Section Pediatric Nutrition.Cereal-based foods, including breakfast (BC) and infant cereals (IC), are among the first solid foods introduced to infants. BC and IC are sources of macro and micronutrients that have bene ficial effects on health, but can also be sources of harmful chemical and microbiological contaminants and nutrients that may lead to adverse health effects at high consumption levels. This study was performed under the RiskBenefit4EU project with the aim of assessing the health impact associated with consumption of BC and IC by Portuguese children under 35 months. Adverse effects associated with the presence of aflatoxins, Bacillus cereus, sodium and free sugars were assessed against the benefits of fiber intake. We applied a risk–benefit assessment approach, and quantified the health impact of changes in consumption of BC and IC from current to various alternative consumption scenarios. Health impact was assessed in terms of disability-adjusted life years. Results showed that moving from the current consumption scenario to considered alternative scenarios results in a gain of healthy life years. Portuguese children can benefit from exchanging intake of IC to BC, if the BC consumed has an adequate nutritional profile in terms of fiber, sodium and free sugars, with levels of aflatoxins reduced as much as possible.This research was funded by European Food Safety Authority (EFSA) (Grant Agreement Number–GA/EFSA/AFSCO/2017/01–GA02) (The authors declare that this manuscript reflects only the authors’ view and EFSA is not responsible for any use that may be made of the information it contains.). R.A., P.A. and C.M. also thanks FCT/MCTES for the financial support to CESAM (UIDP/50017/2020 + UIDB/50017/2020), through national funds. R.A. was supported by FCT Individual CEEC 2018 Assistant Researcher Grant CEECIND/01570/2018.info:eu-repo/semantics/publishedVersio

EGF functionalized polymer-coated gold nanoparticles promote EGF photostability and EGFR internalization for photothermal therapy

The application of functionalized nanocarriers on photothermal therapy for cancer ablation has wide interest. The success of this application depends on the therapeutic efficiency and biocompatibility of the system, but also on the stability and biorecognition of the conjugated protein. This study aims at investigating the hypothesis that EGF functionalized polymer -coated gold nanoparticles promote EGF photostability and EGFR internalization, making these conjugated particles suitable for photothermal therapy. The conjugated gold nanoparticles (100-200 nm) showed a plasmon absorption band located within the near infrared range (650-900 nm), optimal for photothermal therapy applications. The effects of temperature, of polymer-coated gold nanoparticles and of UVB light (295nm) on the fluorescence properties of EGF have been investigated with steady-state and time-resolved fluorescence spectroscopy. The fluorescence properties of EGF, including the formation of Trp and Tyr photoproducts, is modulated by temperature and by the intensity of the excitation light. The presence of polymeric-coated gold nanoparticles reduced or even avoided the formation of Trp and Tyr photoproducts when EGF is exposed to UVB light, protecting this way the structure and function of EGF. Cytotoxicity studies of conjugated nanoparticles carried out in normal-like human keratinocytes showed small, concentration dependent decreases in cell viability (0-25%). Moreover, conjugated nanoparticles could activate and induce the internalization of overexpressed Epidermal Growth Factor Receptor in human lung carcinoma cells. In conclusion, the gold nanoparticles conjugated with Epidermal Growth Factor and coated with biopolymers developed in this work, show a potential application for near infrared photothermal therapy, which may efficiently destroy solid tumours, reducing the damage of the healthy tissue.Support was provided by: Fundacao para a Ciencia e Tecnologia (FCT) for the financial support under the project reference PTDC/BBB-BMC/0611/2012 [https://www.fct.pt/apoios/projectos)]. The work at CBMA was supported by the strategic programme UID/BIA/04050/2013 (POCI-01-0145-FEDER-007569) funded by national funds through the FCT I.P. and by the ERDF through the COMPETE2020 - Programa Operacional Competitividade e Internacionalizacao (POCI) [https://www.fct.pt/apoios/projectos]; European Commission through the project H2020-644242-SAPHELY (https://saphely.eu/project.php) and the project H2020-634013-2-PHOCNOSIS [http://cordis.europa.eu/project/rcn/193268_en.html].The authors would like to thank Fundacao para a Ciencia e Tecnologia (FCT) for the financial support under the project reference PTDC/BBB-BMC/0611/2012. The work at CBMA was supported by the strategic programme UID/BIA/04050/2013 (POCI-01-0145-FEDER-007569) funded by national funds through the FCT I.P. and by the ERDF through the COMPETE2020 - Programa Operacional Competitividade e Internacionalizacao (POCI). The authors acknowledge the funding from the European Commission through the project H2020-644242-SAPHELY and the project H2020-634013-2-PHOCNOSIS. Finally, the authors would also like to thank the master student Joao Lopes from Universidade Lusofona (Portugal) for the help with in vitro cytotoxic assays. Isabel Correia acknowledges FCT for Investigator FCT contract.info:eu-repo/semantics/publishedVersio

Individual common variants exert weak effects on the risk for autism spectrum disorders.

While it is apparent that rare variation can play an important role in the genetic architecture of autism spectrum disorders (ASDs), the contribution of common variation to the risk of developing ASD is less clear. To produce a more comprehensive picture, we report Stage 2 of the Autism Genome Project genome-wide association study, adding 1301 ASD families and bringing the total to 2705 families analysed (Stages 1 and 2). In addition to evaluating the association of individual single nucleotide polymorphisms (SNPs), we also sought evidence that common variants, en masse, might affect the risk. Despite genotyping over a million SNPs covering the genome, no single SNP shows significant association with ASD or selected phenotypes at a genome-wide level. The SNP that achieves the smallest P-value from secondary analyses is rs1718101. It falls in CNTNAP2, a gene previously implicated in susceptibility for ASD. This SNP also shows modest association with age of word/phrase acquisition in ASD subjects, of interest because features of language development are also associated with other variation in CNTNAP2. In contrast, allele scores derived from the transmission of common alleles to Stage 1 cases significantly predict case status in the independent Stage 2 sample. Despite being significant, the variance explained by these allele scores was small (Vm< 1%). Based on results from individual SNPs and their en masse effect on risk, as inferred from the allele score results, it is reasonable to conclude that common variants affect the risk for ASD but their individual effects are modest

Consumption of cereal-based foods by Portuguese children: a risk-benefit assessment

De uma forma geral, o consumo de alimentos pode apresentar potenciais riscos e benefícios para os consumidores. Os alimentos à base de cereais, incluindo os cereais de pequeno-almoço e os cereais infantis, representam componentes importantes da dieta humana e estão entre os primeiros alimentos sólidos que são introduzidos na dieta. Estes alimentos constituem uma fonte importante de vários nutrientes, incluindo o sódio, fibras e açúcares livres, que podem estar associados a efeitos benéficos e adversos para a saúde. Simultaneamente, os alimentos à base de cereais podem também ser veículo de contaminantes químicos (por exemplo, micotoxinas) e microbiológicos (por exemplo, Bacillus cereus). As aflatoxinas, um grupo de micotoxinas que apresenta maior potencial tóxico, são frequentemente detetadas em cereais. No âmbito do projeto RiskBenefit4EU, o presente estudo teve como objetivo avaliar os riscos e os benefícios associados ao consumo de alimentos à base de cereais pelas crianças portuguesas. Os riscos (teores de aflatoxinas e B. cereus, sódio e açúcares livres) e os benefícios (teor de fibra) associados ao consumo de cereais de pequeno-almoço (CPA) foram comparados com aqueles associados ao consumo de cereais infantis (CI). Os resultados obtidos revelaram que a mudança do consumo atual para os cenários alternativos considerados (em especial para o consumo de cereais de pequeno-almoço com características semelhantes ao “Melhor CPA”) poderia resultar num ganho de anos de vida saudável.Foodstuffs, as cereal-based products, may present both potential risks and benefits to consumers. Cereal-based foods including breakfast and infant cereals represent important components of human diets and are among the first solid foods that young children usually eat. Cereal-based products constitute a source of several nutrients, including sodium, fibre and free sugars, which could be associated to beneficial and hazardous effects. Simultaneously, cereal-based foods could also present chemical (e.g. mycotoxins) and microbiological (e.g. Bacillus cereus) contaminants. Aflatoxins, a frequent mycotoxin found in cereals, are undoubtedly the most toxic. Developed under RiskBenefit4EU project, the present study aimed to assess risks and benefits associated with the consumption of cereal-based products by the Portuguese young children. The risks posed by the consumption of breakfast cereals (BC) versus infant cereals (IC), due to aflatoxins, B. cereus, sodium and free sugars, were evaluated against the benefits of the intake of fibre. Obtained results showed that moving from the current consumption to the considered alternative scenarios (especially if considered the consumption of breakfast cereals similar to “Best BC”) could result in a gain of healthy-life years.Este trabalho foi desenvolvido no âmbito do projeto RiskBenefit4EU – Partnering to strengthen the risk-benefit assessment within EU using a holistic approach financiado pelas EFSA Partnering Grants (Grant Agreement Number – GA/EFSA/AFSCO/2017/01 – GA02) 1.info:eu-repo/semantics/publishedVersio