135 research outputs found
Euclid Space Mission: building the sky survey
The Euclid space mission proposes to survey 15000 square degrees of the
extragalactic sky during 6 years, with a step-and-stare technique. The
scheduling of observation sequences is driven by the primary scientific
objectives, spacecraft constraints, calibration requirements and physical
properties of the sky. We present the current reference implementation of the
Euclid survey and on-going work on survey optimization.Comment: to appear in Proceedings IAU Symposium No. 306, "Statistical
Challenges in 21st Century Cosmology", A.F. Heavens, J.-L. Starck & A.
Krone-Martins, ed
Crucial CD8(+) T-lymphocyte cytotoxic role in amphotericin B nanospheres efficacy against experimental visceral leishmaniasis.
This work aims to develop poly(d,l-lactide-co-glycolide) (PLGA)-nanospheres containing amphotericin B (AmB) with suitable physicochemical properties and anti-parasitic activity for visceral leishmaniasis (VL) therapy. When compared with unloaded-PLGA-nanospheres, the AmB-loaded PLGA-nanospheres displayed an increased particle size without affecting the polydispersity and its negative surface charge. AmB stability in the PLGA-nanospheres was > 90% over 60-days at 30°C. The AmB-PLGA-nanospheres demonstrated significant in vitro and in vivo efficacy and preferential accumulation in the visceral organs. In addition, an immune-modulatory effect was observed in mice treated with AmB-PLGA-nanospheres, correlating with improved treatment efficacy. The in vitro cytotoxic response of the T-lymphocytes revealed that AmB-PLGA-nanospheres efficacy against VL infection was strictly due to the action of CD8 + - but not CD4 + -T lymphocytes. Overall, we demonstrate a crucial role for CD8 + cytotoxic T lymphocytes in the efficacy of AmB-PLGA nanospheres, which could represent a potent and affordable alternative for VL therapy. From the Clinical Editor: This study demonstrates a crucial role for CD8+ T lymphocytes in eliminating visceral leishmaniasis in a murine model by enhancing the cytotoxic efficacy of CD8+ T-cells via amphotericin-B-PLGA nanospheres, paving a way to a unique, potentially more potent and cost-effective therapeutic strategy.This work was supported by Fundo Europeu de Desenvolvimento Regional (FEDER) funds through the Operational Competitiveness Program-COMPETE and by national funds through Fundação para a Ciência e a Tecnologia under projects FCOMP-01-0124-FEDER-015718 (PTDC/SAU- ENB/113151/2009) and Fundação Caloust Gulbenkian under project P-105348/2009. D.B. was supported by FCOMP-01-0124-FEDER-015718 (PTDC/SAU-ENB/113151/2009) project. S.A.C.L, J.C. T.B. and R.D-O. were supported by SFRH/BPD/37880/2007, SFRH/BD/48626/2008, SFRH/BD/65387/2009 and IF/01147/2013, respectively. R.S. was supported by Programa Ciência, financed by Programa Operacional Potencial Humano–Quadro de Referência Estratégica Nacional-Tipologia 4.2-Promoção do Emprego Científico, co-funded by Fundo Social Europeu and national funding from the Ministry of Science, Technology and Higher Education
Helicobacter pylori chronic infection and mucosal inflammation switches the human gastric glycosylation pathways
Helicobacter pylori exploits host glycoconjugates to colonize the gastric niche. Infection can persist for decades promoting chronic inflammation, and in a subset of individuals lesions can silently progress to cancer. This study shows that H. pylori chronic infection and gastric tissue inflammation result in a remodeling of the gastric glycophenotype with increased expression of sialyl-Lewis a/x antigens due to transcriptional up-regulation of the B3GNT5, B3GALT5, and FUT3 genes. We observed that H. pylori infected individuals present a marked gastric local pro-inflammatory signature with significantly higher TNF-a levels and demonstrated that TNF-induced activation of the NF-kappaB pathway results in B3GNT5 transcriptional up-regulation. Furthermore, we show that this gastric glycosylation shift, characterized by increased sialylation patterns, favors SabA-mediated H. pylori attachment to human inflamed gastric mucosa. This study provides novel clinically relevant insights into the regulatory mechanisms underlying H. pylori modulation of host glycosylation machinery, and phenotypic alterations crucial for life-long infection. Moreover, the biosynthetic pathways here identified as responsible for gastric mucosa increased sialylation, in response to H. pylori infection, can be exploited as drug targets for hindering bacteria adhesion and counteract the infection chronicity.IPATIMUP integrates the i3S Research Unit, which is partially supported by FCT, the Portuguese Foundation for Science and Technology (PEst C/SAU/LA0003/2013). This work is funded by FEDER funds through the Operational Programme for Competitiveness Factors-COMPETE (NORTE 07 0124 FEDER 000024; FCOMP-01-0124-FEDER028188; FCOMP-01-0124-FEDER 041276) and National Funds through the FCT-Foundation for Science and Technology (EXPL/CTM-BIO/0762/2013, PTDC/BBB-EBI/0786/2012) and acknowledges support by the EuropeanUnion (Seventh Framework Programme GastricGlycoExplorer project, grant number 316929). Grants were received from FCT, POPH (Programa Operacional Potencial Humano) and FSE (Fundo Social Europeu) (SFRH/BPD/75871/2011 to AM;SFRH/SINTD/60034/2009 to RMP; SFRH/BPD/84084/2012 to RMF; SFRH/BPD/89764/2012 to PO). AM acknowledges EMBO for a Short-Term Fellowship (EMBO ASTF 330-212). Transcript analysis was funded by NIH (grant P41GM103490) to KWM
Atmospheric dust deposition and levels of trace elements in an industrial city in the Portuguese coastline
O presente estudo pretendeu (i) identificar padrões geoquímicos
espaciais e temporais na deposição atmosférica, e (ii) avaliar potenciais
contribuições de fontes locais e alóctones para a composição química das
poeiras atmosféricas no concelho de Estarreja. Dois coletores foram
colocados em áreas exteriores de duas escolas localizadas poucos
quilómetros a sul da zona industrial. A recolha das amostras foi realizada
mensalmente, de maio a agosto de 2018. As frações solúvel e insolúvel da
deposição atmosférica foram analisadas por ICP-MS para determinar as
concentrações quase-totais dos elementos químicos. Os resultados
mostram a ocorrência de dois eventos distintos de maior fluxo de
deposição atmosférica: (i) um em maio, caracterizado pela deposição de
elementos traço em formas solúveis, detetado em ambas as escolas e (ii)
um segundo em agosto, caracterizado pela deposição de elementos
maiores em formas insolúveis, detetado apenas na escola mais distante do
complexo industrial. No geral, os resultados indicam uma deposição
antrópica de aerossóis em maio e uma deposição de partículas litogénicas
em agosto.Due to their high toxicity and reactivity in atmospheric
particles, metl(loid)s are a category of pollutants of great concern in air
pollution. The present study aimed (i) to identify spatial and temporal
geochemical patterns in atmospheric deposition, and (ii) to evaluate
potential contributions from local and regional sources to the chemical
composition of atmospheric dust, in the industrial city of Estarreja. Two
collectors were placed in exterior areas of two schools located few
kilometres south from the industrial zone, one within an urban setting and
another in a rural environment. Samples were collected monthly from
May and August 2018. The soluble and insoluble fractions of
atmospheric were analysed by ICP-MS to determine near-total
concentrations of the chemical elements. The results indicate two distinct
events of higher atmospheric deposition flux. The first event, detected in
both schools, occurred in May and is characterized by the deposition of
trace elements in soluble forms. The second occurred in August and is
characterized by the deposition of major elements in insoluble forms.
This later episode was detected only at the school furthest from the
industrial complex. Overall, the results indicate an anthropogenic aerosol
deposition in May and a lithogenic particle deposition in August.Este trabalho é cofinanciado pela União Europeia através do
Fundo Europeu de Desenvolvimento Regional, baseado no
COMPETE 2020 (Programa Operacional de Competitividade e
Internacionalização), no projeto ICT (UIDB/04683/2020), no
projeto GeoBioTec (UIDB/04035/2020) e nos fundos nacionais
fornecidos pela Fundação para a Ciência e Tecnologia. Os
autores agradecem à Direção, aos docentes e aos funcionários do
Agrupamento de Escolas de Estarreja a preciosa colaboração
durante o período de recolha das amostra
A CRISPR screen identifies a pathway required for paraquat-induced cell death
Paraquat, a herbicide linked to Parkinson's disease, generates reactive oxygen species (ROS), which causes cell death. Because the source of paraquat-induced ROS production remains unknown, we conducted a CRISPR-based positive-selection screen to identify metabolic genes essential for paraquat-induced cell death. Our screen uncovered three genes, POR (cytochrome P450 oxidoreductase), ATP7A (copper transporter), and SLC45A4 (sucrose transporter), required for paraquat-induced cell death. Furthermore, our results revealed POR as the source of paraquat-induced ROS production. Thus, our study highlights the use of functional genomic screens for uncovering redox biology
Intraprostatic Botulinum Toxin Type A injection in patients with benign prostatic enlargement: duration of the effect of a single treatment
<p>Abstract</p> <p>Background</p> <p>Botulinum Toxin Type-A (BoNT/A) intraprostatic injection can induce prostatic involution and improve LUTS and urinary flow in patients with Benign Prostatic Enlargement (BPE). However, the duration of these effects is unknown. The objective of this work was to determine the duration of prostate volume reduction after one single intraprostatic injection of 200U of Botulinum Toxin Type-A.</p> <p>Methods</p> <p>This is an extension of a 6 month study in which 21 frail elderly patients with refractory urinary retention and unfit for surgery were submitted to intraprostatic injection of BoNT/A-200U, by ultrasound guided transrectal approach. In spite of frail conditions, eleven patients could be followed during 18 months. Prostate volume, total serum PSA, maximal flow rate (Qmax), residual volume (PVR) and IPSS-QoL scores were determined at 1, 3, 6, 12 and 18 months post-treatment.</p> <p>Results</p> <p>Mean prostate volume at baseline, 82 ± 16 ml progressively decreased from month one coming to 49 ± 9,5 ml (p = 0,003) at month six. From this moment on, prostate volume slowly recovered, becoming identical to baseline at 18 months (73 ± 16 ml, p = 0.03). Albeit non significant, serum PSA showed a 25% decrease from baseline to month 6. The 11 patients resumed spontaneous voiding at month one. Mean Qmax was 11,3 ± 1,7 ml/sec and remained unchanged during the follow-up period. PVR ranged from 55 ± 17 to 82 ± 20 ml and IPSS score from10 to 12 points.</p> <p>Conclusion</p> <p>Intraprostatic BoNT/A injection is safe and can reduce prostate volume for a period of 18 months. During this time a marked symptomatic improvement can be maintained.</p
Cetuximab plus platinum-based chemotherapy in head and neck Squamous Cell Carcinoma: a retrospective study in a single Comprehensive European Cancer Institution
Background: The use of cetuximab in combination with platinum (P) plus 5-fluorouracil (F) has previously been demonstrated to be effective in the treatment of metastatic squamous cell cancer of head and neck (SCCHN). We investigated the efficacy and outcome of this protocol as a first-line treatment for patients with recurrent or metastatic disease. We evaluated overall-survival (OS), progression-free-survival (PFS), overall response rate (ORR) and the treatment toxicity profile in a retrospective cohort. Patients and Methods: This study enrolled 121 patients with untreated recurrent or metastatic SCCHN. The patients received PF+ cetuximab every 3 weeks for a maximum of 6 cycles. Patients with stable disease who received PF+ cetuximab continued to receive cetuximab until disease progressed or unacceptable toxic effects were experienced, whichever occurred first. Results: The median patient age was 53 (37-78) years. The patient cohort was 86.8% male. The addition of cetuximab to PF in the recurrent or metastatic setting provided an OS of 11 months (Confidential Interval, CI, 95%, 8.684-13.316) and PFS of 8 months (CI 95%, 6.051-9.949). The disease control rate was 48.9%, and the ORR was 23.91%. The most common grade 3 or 4 adverse events in the PF+ cetuximab regimen were febrile neutropenia (5.7%), skin rash (3.8%) and mucosistis (3.8%). Conclusions: The results of this study suggest that cetuximab plus platinum-fluorouracil chemotherapy is a good option for systemic treatment in advanced SSCHN patients. This regimen has a well-tolerated toxicity profile.info:eu-repo/semantics/publishedVersio
A breakthrough on Amanita phalloides poisoning: an effective antidotal effect by polymyxin B
Amanita phalloides is responsible for more than 90 % of mushroom-related fatalities, and no effective antidote is available. a-Amanitin, the main toxin of A. phalloides, inhibits RNA polymerase II (RNAP II), causing hepatic and kidney failure. In silico studies included docking and molecular dynamics simulation coupled to molecular mechanics with generalized Born and surface area method energy decomposition on RNAP II. They were performed with a clinical drug that shares chemical similarities to a-amanitin, polymyxin B. The results show that polymyxin B potentially binds to RNAP II in the same interface of a-amanitin, preventing the toxin from binding to RNAP II. In vivo, the inhibition of the mRNA transcripts elicited by a-amanitin was efficiently reverted by polymyxin B in the kidneys. Moreover, polymyxin B significantly decreased the hepatic and renal a-amanitin-induced injury as seen by the histology and hepatic aminotransferases plasma data. In the survival assay, all animals exposed to a-amanitin died within 5 days, whereas 50 % survived up to 30 days when polymyxin B was administered 4, 8, and 12 h post-a-amanitin. Moreover, a single dose of polymyxin B administered concomitantly with a-amanitin was able to guarantee 100 % survival. Polymyxin B protects RNAP II from inactivation leading to an effective prevention of organ damage and increasing survival in a-amanitin-treated animals. The present use of clinically relevant concentrations of an already human-use-approved drug prompts the use of polymyxin B as an antidote for A. phalloides poisoning in humans.Juliana Garcia, Vera Marisa Costa, Ricardo Dinis-Oliveira and Ricardo Silvestre thank FCT-Foundation for Science and Technology-for their PhD grant (SFRH/BD/74979/2010), Post-doc grants (SFRH/BPD/63746/2009 and SFRH/BPD/110001/2015) and Investigator grants (IF/01147/2013) and (IF/00021/2014), respectively. This work was supported by the Fundacao para a Ciencia e Tecnologia (FCT) - project PTDC/DTPFTO/4973/2014 - and the European Union (FEDER funds through COMPETE) and National Funds (FCT, Fundacao para a Ciencia e Tecnologia) through project Pest-C/EQB/LA0006/2013
WldS Reduces Paraquat-Induced Cytotoxicity via SIRT1 in Non-Neuronal Cells by Attenuating the Depletion of NAD
WldS is a fusion protein with NAD synthesis activity, and has been reported to protect axonal and synaptic compartments of neurons from various mechanical, genetic and chemical insults. However, whether WldS can protect non-neuronal cells against toxic chemicals is largely unknown. Here we found that WldS significantly reduced the cytotoxicity of bipyridylium herbicides paraquat and diquat in mouse embryonic fibroblasts, but had no effect on the cytotoxicity induced by chromium (VI), hydrogen peroxide, etoposide, tunicamycin or brefeldin A. WldS also slowed down the death of mice induced by intraperitoneal injection of paraquat. Further studies demonstrated that WldS markedly attenuated mitochondrial injury including disruption of mitochondrial membrane potential, structural damage and decline of ATP induced by paraquat. Disruption of the NAD synthesis activity of WldS by an H112A or F116S point mutation resulted in loss of its protective function against paraquat-induced cell death. Furthermore, WldS delayed the decrease of intracellular NAD levels induced by paraquat. Similarly, treatment with NAD or its precursor nicotinamide mononucleotide attenuated paraquat-induced cytotoxicity and decline of ATP and NAD levels. In addition, we showed that SIRT1 was required for both exogenous NAD and WldS-mediated cellular protection against paraquat. These findings suggest that NAD and SIRT1 mediate the protective function of WldS against the cytotoxicity induced by paraquat, which provides new clues for the mechanisms underlying the protective function of WldS in both neuronal and non-neuronal cells, and implies that attenuation of NAD depletion may be effective to alleviate paraquat poisoning
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