148 research outputs found
Assessing the Influence of Neuroinflammation on Neurogenesis: In Vitro Models Using Neural Stem Cells and Microglia as Valuable Research Tools
Nitric Oxide Regulates Neurogenesis in the Hippocampus following Seizures
Hippocampal neurogenesis is changed by brain injury. When neuroinflammation accompanies injury, activation of resident microglial cells promotes the release of inflammatory cytokines and reactive oxygen/nitrogen species like nitric oxide (NO). In these conditions, NO promotes proliferation of neural stem cells (NSC) in the hippocampus. However, little is known about the role of NO in the survival and differentiation of newborn cells in the injured dentate gyrus. Here we investigated the role of NO following seizures in the regulation of proliferation, migration, differentiation, and survival of NSC in the hippocampus using the kainic acid (KA) induced seizuremouse model. We show that NO increased the proliferation of NSC and the number of neuroblasts following seizures but was detrimental to the survival of newborn neurons. NO was also required for the maintenance of long-term neuroinflammation. Taken together, our data show that NO positively contributes to the initial stages of neurogenesis following seizures but compromises survival of newborn neurons.Foundation for Science and Technology (FCT, Portugal); COMPETE; FEDER [PTDC/SAU-NEU/102612/2008, PTDC/NEU-OSD/0473/2012, PEst-C/SAU/LA0001/2013-2014, PEst-OE/EQB/LA0023/2013-2014]; FCT, Portugal [SFRH/BPD/78901/2011, SFRH/BD/77903/2011
Regulation of injury-induced neurogenesis by Nitric Oxide
The finding that neural stem cells (NSCs) are able to divide, migrate, and differentiate into several cellular types in the adult brain raised a new hope for restorative neurology. Nitric oxide (NO), a pleiotropic signaling molecule in the central nervous system (CNS), has been described to be able to modulate neurogenesis, acting as a pro-or antineurogenic agent. Some authors suggest that NO is a physiological inhibitor of neurogenesis, while others described NO to favor neurogenesis, particularly under inflammatory conditions. Thus, targeting the NO system may be a powerful strategy to control the formation of new neurons. However, the exact mechanisms by which NO regulates neural proliferation and differentiation are not yet completely clarified. In this paper we will discuss the potential interest of the modulation of the NO system for the treatment of neurodegenerative diseases or other pathological conditions that may affect the CNS.Foundation for Science and Technology, (FCT, Portugal); COMPETE
What is Science made of
Science education, which deals with the sharing and communication of science contents, processes and results with people not belonging to the scientific communities, is being increasingly considered a matter of national concern and a priority in the educational agendas of several countries. Promoting and enhancing scientific literacy of citizens is currently a major mission to modern societies, as it is believed that it will contribute to
promote and train for a better informed, as well as a more conscious, critical and committed citizenship (Fiolhais,
2011). But the education for this scientific literacy is also a great challenge as target individuals may be very
diverse, either in terms of age or in what concerns knowledge backgrounds, and can range from children to
adults within the general public. The language, the format and the way this communication/ education is made
should obviously take into consideration the public profiles to which is addressed, being as clear, accurate and
demystified as possible. Also, several studies have geared to the view that scientific literacy is best taught by
seeing science education as “education through science” as opposed to “science through education.” (Holbrook
and Rannikmae, 2009)
Although science and technology are ubiquitous in our everyday lives, their role and impacts are not perceived
equally by all citizens. For a large part of the population, science, in particular, is still something unknown, often
complex, strange and distant — being seen as something intangible for those not directly related to the scientific
arena. For others, scientists are still seen as a distracted figure wearing a white tap and glasses fully dedicated
to the pursuit of knowledge, though this image is gradually disappearing from the nowadays collective
imagination.
And what is Science made of? Is it possible to get a clear, precise and instantaneous response? Probably not!
Much of what happens in science and in scientific research is still seen by many as pure magic, something
transcendental. However it is important to discredit such stereotypes, throwing light on scientists´ work, science
tools as well as on the human skills and qualities that make science happens. With this goal, we idealized and
prepared an exhibition entitled “What is Science made of", aiming to create a new relationship between science
and the general public, in an appealing, innovative and challenging way. "What is Science made of" is a set of
twelve images, each one starting from a common laboratory object. The images represent a group of words
expressing concepts and values that ideally mirror the relationship between science and scientists. In this work
we justify the choice of the twelve words, describe the design and assembly of the set of images as well as its
exhibition and the public receptiveness and reactions to such initiative.info:eu-repo/semantics/publishedVersio
Production of high added value products from eggshells
There are an increasing number of food companies addressing sustainable-manufacturing practices as part of social responsibility reporting. The egg processing industry produces several tons of eggshell residues which are a major environmental problem and represent a significant cost for these industries (ca. 0.6 % of sales). The main goal of this work is to produce high added value products, namely collagen and bioactive peptides, using the remnant of collagen extraction from the eggshell membrane. The target market of the products obtained is the biomedical, pharmaceutical, cosmetics and food industry.
The separation of the shell and the membrane was optimized and a chemical-physical process was performed having a yield of 9 % (w membrane/w shell). Times and yields for different separation methods were calculated and the economic viability of the process was studied.
In order to optimize collagen extraction from the eggshell membranes several variables were studied (e.g. temperature, enzyme concentration and time). The collagen obtained was separated using saline precipitation steps and different collagen types were identified. The collagen types were visualized using SDS-electrophoresis and total quantification of collagen was made by hydroxyproline method.
Moreover, the residue after collagen extraction was further digested with different enzymes, namely pancreatin, tripsin and lysin and the peptides profile was determined by HPLC-UV method.
The results showed promising strategies for using this technology at industrial scale as an economic viable technology for producing high added value products from eggshells membranes. This technology will equally contribute to reducing the environmental problem associated with these residues
Mathematical modelling of convective drying of Galega kale
info:eu-repo/semantics/publishedVersio
The prognostic value of worsening renal function and its timing
Copyright © 2023 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.INTRODUCTION: Acute decompensated heart failure (ADHF) admissions are frequently complicated by different patterns of serum creatinine (SCr) elevation. We aimed to assess the prognostic impact of worsening renal function (WRF) based on the timing of its occurrence. METHODS: This was a retrospective cohort of patients admitted for ADHF. Standard WRF was defined as an increase in SCr of ≥0.3 mg/dl during hospitalization. WRF timing was classified as early (within 48 hours of admission) or late (>48 hours). Acute kidney injury (AKI) at admission was defined as a rise in SCr of ≥0.3 mg/dl from outpatient baseline measurement to first measurement at admission. The primary endpoint was a composite of all-cause mortality or hospitalization for cardiovascular events at one-year follow-up. RESULTS: Overall, 249 patients were included (mean age 77±11 years, 62% with preserved left ventricular ejection fraction). Early WRF occurred in 49 patients (19.7%) and was associated with a higher risk of the primary outcome (HR 2.49; 95% CI 1.66-3.73), whereas late WRF was not (p=0.411). After stratification for the presence of early WRF and/or AKI at admission, only patients with early WRF but no AKI at admission and patients with both AKI at admission and early WRF showed a higher risk of the primary outcome after multivariate Cox regression. CONCLUSION: Early WRF was associated with a higher risk of the primary outcome. The timing of WRF seems to be an important factor to take into account when considering the prognostic impact of creatinine variations during hospitalization for ADHF.proofepub_ahead_of_prin
Evaluation of drying and storage conditions on nutritional and sensory properties of dried galega kale (Brassica oleracea L. var. Acephala)
This work evaluated the effect of the air-drying temperature and vacuum packaging on quality and nutritional compounds of dehydrated galega kale, previously steam blanched, during 5 months of storage. When compared with the vacuum packaged kale, the packaging without vacuum yielded improved nutritional features, in general. This approach combined with a drying temperature of 40°C resulted in retention percentages of 62, 38, 92, and 48% for vitamin C, total phenolic content, total antioxidant capacity, and chlorophylls, respectively. The acceptance of the dried product by the consumer was assessed through a focus group. The participants classified the product as a practical and convenient alternative to cook healthier dishes. The appearance of dried galega kale was described as being fragile and being with nice smell, natural colour, and flavour similar to the fresh product. In conclusion, the herein presented product was addressed as an innovation with multiple possible applications in several recipes.info:eu-repo/semantics/publishedVersio
Analysis of microsatellite instability in medulloblastoma
Medulloblastoma is the most common malignant brain tumor in children. The presence of microsatellite instability (MSI) in brain tumors, particularly medulloblastomas, has not been properly addressed. The aim of the present study was to evaluate the role of MSI in medulloblastoma carcinogenesis. MSI status was determined in 36 patients using a pentaplex PCR of quasimonomorphic markers (NR27, NR21, NR24, BAT25, and BAT26). Methylation status of mismatch repair (MMR) genes was achieved by methylation-specific multiplex ligation-dependent probe amplification (MLPA). In addition, MutS homolog 6 (MSH6) expression was determined by immunohistochemistry. Mutations of 10 MSI target genes (TCF4, XRCC2, MBD4, MRE11, ATR, MSH3, TGFBR2, RAD50, MSH6, and BAX) were studied by pentaplex PCR followed by analysis with GeneScan 3.7 software. Mutation analysis of hotspot regions of beta-catenin (CTNNB1) and BRAF (v-raf murine sarcoma viral oncogene homolog B1) oncogenes was performed by PCR single-strand conformation polymorphism analysis followed by direct sequencing. Among the 36 tumors, we found four (11%) cases with instability, one with high MSI and three with low MSI. Methylation analysis of MMR genes in cases presenting shifts on the MSI markers revealed mild hypermethylation of MSH6 in 75% of cases, yet MSH6 was expressed in all the tumors. The MSI target genes MBD4 (methyl-CpG binding domain protein 4) and MRE11 (meiotic recombination 11 homolog A) were mutated in two different tumors. No CTNNB1 or BRAF mutations were found. This study is the most comprehensive analysis of MSI in medulloblastomas to date. We observed the presence of MSI together with mutations of MSI target genes in a small fraction of cases, suggesting a new genetic pathway for a role in medulloblastoma development.M.V.-P. is the recipient of a Ph.D. fellowship (SFRH/BD/29145/2006), and I.A. is the recipient
of a research fellowship (SFRH/BI/33160/2007) from
Fundação para a Ciência e Tecnologia, Portugal. This
study was partially supported by a grant from Clinical
de Radioterapia do Porto, Portugal
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