2,283 research outputs found
Current Developments in Antioxidant Therapies for Spinal Cord Injury
When spinal cord injury (SCI) occurs, numerous sources of reactive oxygen species and nitrogen species may be active within first minutes or hours and even reactivate few days later. Free radical formation and lipid peroxidation (LP) have been described as an important mechanism in the beginning and accelerated progress in the development of diverse pathologies, importantly in those related to central nervous system. The compromise of molecules and cellular structures due to the oxidative state of microenvironment in SCI may determinate survival or apoptosis of resident and infiltrating cells and polarization toward an inflammatory response, which lead to an extension of damaged tissue and loss of neuronal function, or a regulatory/regenerative response. The investigation of new antioxidant agents and their action at a molecular level begins to reveal mechanisms that, if correctly modulated, promise an improvement in recovery of functions with respect to conventional pharmacological therapies. In this chapter, we will review the general mechanisms of oxidative stress and lipid peroxidation, those antioxidant treatments in experimental development and clinical phase, as well as their achievements and limitations
Double protonation of a cis-Bipyridoallenophane detected via Chiral-Sensing Switch: the role of Ion Pairs
We prove that the confinement of the conformational space of pyridoallenophanes leads to intense chiroptical responses. Unlike the cyclic dimer [142], single-conformation [141]pyridoallenophanes isomerize under thermal and photochemical conditions. Yet, less-strained [141]-bipyridoallenophanes are stable and are prepared successfully. They, unexpectedly, undergo double protonation as a result of cooperative ion-pairing and hydrogen bonding. The complex formation forces a single configuration of the axis connecting both pyridyl rings recognized by a diagnostic circular dichroism (CD) signal at 330 nm.Agencia Estatal de InvestigaciĂłn | Ref. CTQ2017-84354-PAgencia Estatal de InvestigaciĂłn | Ref. CTQ2017-85919-RXunta de Galicia | Ref. IN607C 2016/03Xunta de Galicia | Ref. ED431C 2017/70Xunta de Galicia | Ref. Ref. ED431G/0
Accessible triplet excited states in the photoisomerization of allenes with extended conjugation
A series of bidentate allene- and enyne-containing ligands have been synthesized and the photochemical properties of their rhenium(I) complexes have been studied. These complexes exhibit facile isomerization of the conjugated double bonds upon ambient light exposure. Simulations unveiled a very efficient intersystem crossing and the consequent key role of the triplet states in the observed photochemistry of these substrates upon rhenium(I) complexation.Agencia Estatal de InvestigaciĂłn | Ref. CTQ2017-85919-RXunta de Galicia | Ref. EC431C 2021/4
Design and Construction for Hydroxides Based Air Conditioning System with Solar Collectors for Confined Roofs
In this chapter, the methodology to determinate heat load is revised and presented. The main parameters must be fixed as function of climatization, internal thermic conditions (comfort, temperature, and humid) and the activities. According with literature, the roof structural requirements were checked. These are an important parameter because it represents the limits to the system such as load by devices (weight of equipment), orientation in solar systems (operating conditions), and building materials. The method of calculation of solar available is shown; the aim is to achieve the major collection of solar energy. Finally, the plate heat exchangers can be fabricated in gasketed, welded or module welded design characterized by the model in which the flow channels for the two heat exchanging media are sealed. The kind of exchanger is suitable depending on your requirements. The thermodynamic method of calculation of sizing the exchangers is reviewed. The aim of this section is to find the suitable devices for the operation of air-conditioning absorption system based on hydroxide
Carbon, nitrogen, and oxygen stable isotopes in modern tooth enamel: A case study from Gorongosa National Park, central Mozambique
The analyses of the stable isotope ratios of carbon (delta C-13), nitrogen (delta N-15), and oxygen (delta O-18) in animal tissues are powerful tools for reconstructing the feeding behavior of individual animals and characterizing trophic interactions in food webs. Of these biomaterials, tooth enamel is the hardest, most mineralized vertebrate tissue and therefore least likely to be affected by chemical alteration (i.e., its isotopic composition can be preserved over millions of years), making it an important and widely available archive for biologists and paleontologists. Here, we present the first combined measurements of delta C-13, delta N-15, and delta O-18 in enamel from the teeth of modern fauna (herbivores, carnivores, and omnivores) from the well-studied ecosystem of Gorongosa National Park (GNP) in central Mozambique. We use two novel methods to produce high-precision stable isotope enamel data: (i) the "oxidation-denitrification method," which permits the measurement of mineral-bound organic nitrogen in tooth enamel (delta N-15(enamel)), which until now, has not been possible due to enamel's low organic content, and (ii) the "cold trap method," which greatly reduces the sample size required for traditional measurements of inorganic delta C-13(enamel) and delta O-18(enamel) (from >= 0.5 to <= 0.1 mg), permitting analysis of small or valuable teeth and high-resolution serial sampling of enamel. The stable isotope results for GNP fauna reveal important ecological information about the trophic level, dietary niche, and resource consumption. delta N-15(enamel) values clearly differentiate trophic level (i.e., carnivore delta N-15(enamel) values are 4.0 parts per thousand higher, on average, than herbivores), delta C-13(enamel) values distinguish C-3 and/or C-4 biomass consumption, and delta O-18(enamel) values reflect local meteoric water (delta O-18(water)) in the park. Analysis of combined carbon, nitrogen, and oxygen stable isotope data permits geochemical separation of grazers, browsers, omnivores, and carnivores according to their isotopic niche, while mixed-feeding herbivores cannot be clearly distinguished from other dietary groups. These results confirm that combined C, N, and O isotope analyses of a single aliquot of tooth enamel can be used to reconstruct diet and trophic niches. Given its resistance to chemical alteration, the analysis of these three isotopes in tooth enamel has a high potential to open new avenues of research in (paleo)ecology and paleontology.info:eu-repo/semantics/publishedVersio
Phylogenetic Analysis of Bolivian Bat Trypanosomes of the Subgenus Schizotrypanum Based on Cytochrome b Sequence and Minicircle Analyses
The aim of this study was to establish the phylogenetic relationships of trypanosomes present in blood samples of Bolivian Carollia bats. Eighteen cloned stocks were isolated from 115 bats belonging to Carollia perspicillata (Phyllostomidae) from three Amazonian areas of the Chapare Province of Bolivia and studied by xenodiagnosis using the vectors Rhodnius robustus and Triatoma infestans (Trypanosoma cruzi marenkellei) or haemoculture (Trypanosoma dionisii). The PCR DNA amplified was analyzed by nucleotide sequences of maxicircles encoding cytochrome b and by means of the molecular size of hyper variable regions of minicircles. Ten samples were classified as Trypanosoma cruzi marinkellei and 8 samples as Trypanosoma dionisii. The two species have a different molecular size profile with respect to the amplified regions of minicircles and also with respect to Trypanosoma cruzi and Trypanosoma rangeli used for comparative purpose. We conclude the presence of two species of bat trypanosomes in these samples, which can clearly be identified by the methods used in this study. The presence of these trypanosomes in Amazonian bats is discussed
Fine mapping and conditional analysis identify a new mutation in the autoimmunity susceptibility gene BLK that leads to reduced half-life of the BLK protein
OBJECTIVES: To perform fine mapping of the autoimmunity susceptibility gene BLK and identify functional variants involved in systemic lupus erythematosus (SLE).
METHODS: Genotyping of 1163 European SLE patients and 1482 controls and imputation were performed covering the BLK gene with 158 single-nucleotide polymorphisms. Logistic regression analysis was done using PLINK and conditional analyses using GENABEL's test score. Transfections of BLK constructs on HEK293 cells containing the novel mutation or the wild type form were analysed for their effect on protein half-life using a protein stability assay, cycloheximide and western blot. CHiP-qPCR for detection of nuclear factor Îș B (NFkB) binding.
RESULTS: Fine mapping of BLK identified two independent genetic effects with functional consequences: one represented by two tightly linked associated haplotype blocks significantly enriched for NFÎșB-binding sites and numerous putative regulatory variants whose risk alleles correlated with low BLK mRNA levels. Binding of NFkBp50 and p65 to an associated 1.2 Kb haplotype segment was confirmed. A second independent genetic effect was represented by an Ala71Thr, low-frequency missense substitution with an OR=2.31 (95% CI 1.38 to 3.86). The 71Thr decreased BLK protein half-life.
CONCLUSIONS: These results show that rare and common regulatory variants in BLK are involved in disease susceptibility and both, albeit independently, lead to reduced levels of BLK protein
The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in
operation since July 2014. This paper describes the second data release from
this phase, and the fourteenth from SDSS overall (making this, Data Release
Fourteen or DR14). This release makes public data taken by SDSS-IV in its first
two years of operation (July 2014-2016). Like all previous SDSS releases, DR14
is cumulative, including the most recent reductions and calibrations of all
data taken by SDSS since the first phase began operations in 2000. New in DR14
is the first public release of data from the extended Baryon Oscillation
Spectroscopic Survey (eBOSS); the first data from the second phase of the
Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2),
including stellar parameter estimates from an innovative data driven machine
learning algorithm known as "The Cannon"; and almost twice as many data cubes
from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous
release (N = 2812 in total). This paper describes the location and format of
the publicly available data from SDSS-IV surveys. We provide references to the
important technical papers describing how these data have been taken (both
targeting and observation details) and processed for scientific use. The SDSS
website (www.sdss.org) has been updated for this release, and provides links to
data downloads, as well as tutorials and examples of data use. SDSS-IV is
planning to continue to collect astronomical data until 2020, and will be
followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14
happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov
2017 (this is the "post-print" and "post-proofs" version; minor corrections
only from v1, and most of errors found in proofs corrected
Multilateral benefit-sharing from digital sequence information will support both science and biodiversity conservation
Open access to sequence data is a cornerstone of biology and biodiversity research, but has created tension under the United Nations Convention on Biological Diversity (CBD). Policy decisions could compromise research and development, unless a practical multilateral solution is implemented.This workwas funded by the German Federal Ministry of Education and Research (BMBF) WiLDSI
031B0862 (A.H.S., J.O., and J.F.) and Horizon Europe EVA-GLOBAL 871029 (A.H.S.).
I.K.M. was supported by the National Center for Biotechnology Information of the
National Library of Medicine, National Institutes of Health
Polymorphisms within autophagy-related genes as susceptibility biomarkers for multiple myeloma: a meta-analysis of three large cohorts and functional characterization
Functional data used in this project have been meticulously catalogued and archived in the BBMRI-NL data infrastructure (https://hfgp.bbmri.nl/, accessed on 12 February 2020) using the MOLGENIS open-source platform for scientific data.Multiple myeloma (MM) arises following malignant proliferation of plasma cells in the
bone marrow, that secrete high amounts of specific monoclonal immunoglobulins or light chains,
resulting in the massive production of unfolded or misfolded proteins. Autophagy can have a
dual role in tumorigenesis, by eliminating these abnormal proteins to avoid cancer development,
but also ensuring MM cell survival and promoting resistance to treatments. To date no studies
have determined the impact of genetic variation in autophagy-related genes on MM risk. We
performed meta-analysis of germline genetic data on 234 autophagy-related genes from three independent study populations including 13,387 subjects of European ancestry (6863 MM patients and
6524 controls) and examined correlations of statistically significant single nucleotide polymorphisms
(SNPs; p < 1 Ă 10â9) with immune responses in whole blood, peripheral blood mononuclear
cells (PBMCs), and monocyte-derived macrophages (MDM) from a large population of healthy
donors from the Human Functional Genomic Project (HFGP). We identified SNPs in six loci, CD46,
IKBKE, PARK2, ULK4, ATG5, and CDKN2A associated with MM risk (p = 4.47 Ă 10â4â5.79 Ă 10â14).
Mechanistically, we found that the ULK4rs6599175 SNP correlated with circulating concentrations
of vitamin D3 (p = 4.0 Ă 10â4), whereas the IKBKErs17433804 SNP correlated with the number of
transitional CD24+CD38+ B cells (p = 4.8 Ă 10â4) and circulating serum concentrations of Monocyte
hemoattractant Protein (MCP)-2 (p = 3.6 Ă 10â4). We also found that the CD46rs1142469 SNP corre lated with numbers of CD19+ B cells, CD19+CD3â B cells, CD5+ IgDâ cells, IgMâ cells, IgDâIgMâ
cells, and CD4âCD8â PBMCs (p = 4.9 Ă 10â4â8.6 Ă 10â4
) and circulating concentrations of interleukin (IL)-20 (p = 0.00082). Finally, we observed that the CDKN2Ars2811710 SNP correlated with levels
of CD4+EMCD45RO+CD27â cells (p = 9.3 Ă 10â4
). These results suggest that genetic variants within
these six loci influence MM risk through the modulation of specific subsets of immune cells, as well
as vitamin D3â, MCP-2â, and IL20-dependent pathways.This work was supported by the European Unionâs Horizon 2020 research and innovation program, N° 856620 and by grants from the Instituto de Salud Carlos III and FEDER (Madrid, Spain; PI17/02256 and PI20/01845), ConsejerĂa de TransformaciĂłn EconĂłmica, Industria, Conocimiento y Universidades and FEDER (PY20/01282), from the CRIS foundation against cancer, from the Cancer Network of Excellence (RD12/10 Red de CĂĄncer), from the Dietmar Hopp Foundation and the German Ministry of Education and Science (BMBF: CLIOMMICS [01ZX1309]), and from National Cancer Institute of the National Institutes of Health under award numbers: R01CA186646, U01CA249955 (EEB).This work was also funded d by Portuguese National funds, through the Foundation for Science and Technology (FCT)âproject UIDB/50026/2020 and UIDP/50026/2020 and by the project NORTE-01-0145-FEDER-000055, supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF)
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