371 research outputs found
Comprehensive behavioral testing in the R6/2 mouse model of Huntington's disease shows no benefit from CoQ10 or minocycline
Previous studies of the effects of coenzyme Q10 and minocycline on mouse models of Huntington’s disease have produced conflicting results regarding their efficacy in behavioral tests. Using our recently published best practices for husbandry and testing for mouse models of Huntington’s disease, we report that neither coenzyme Q10 nor minocycline had significant beneficial effects on measures of motor function, general health (open field, rotarod, grip strength, rearing-climbing, body weight and survival) in the R6/2 mouse model. The higher doses of minocycline, on the contrary, reduced survival. We were thus unable to confirm the previously reported benefits for these two drugs, and we discuss potential reasons for these discrepancies, such as the effects of husbandry and nutrition
Glutamate Decarboxylases in Nonneural Cells of Rat Testis and Oviduct: Differential Expression of GAD 65 and GAD 67
Γ-Aminobutyric acid (GABA) and its synthetic enzyme, glutamate decarboxylase (GAD), are not limited to the nervous system but are also found in nonneural tissues. The mammalian brain contains at least two forms of GAD (GAD 67 and GAD 65 ), which differ from each other in size, sequence, immunoreactivity, and their interaction with the cofactor pyridoxal 5′-phosphate (PLP). We used cDNAs and antibodies specific to GAD 65 and GAD 67 to study the molecular identity of GADs in peripheral tissues. We detected GAD and GAD mRNAs in rat oviduct and testis. In oviduct, the size of GAD, its response to PLP, its immunoreactivity, and its hybridization to specific RNA and DNA probes all indicate the specific expression of the GAD 65 gene. In contrast, rat testis expresses the GAD 67 gene. The GAD in these two reproductive tissues is not in neurons but in nonneural cells. The localization of brain GAD and GAD mRNAs in the mucosal epithelial cells of the oviduct and in spermatocytes and spermatids of the testis shows that GAD is not limited to neurons and that GABA may have functions other than neurotransmission.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66211/1/j.1471-4159.1992.tb09763.x.pd
Minor early embryonic chick hemoglobin M. Amino acid sequences of the epsilon and alpha D chains
Erythrocytes of the early chick embryo contain four hemoglobins, two major and two minor. In this paper, we present amino acid sequences for the beta-like and alpha-like chains of HbM, the least abundant of the four early chick hemoglobins. The complete amino acid sequence of the beta-like chain of HbM is identical with that of the epsilon chain of HbE, the other minor early embryonic hemoglobin in the domestic chicken. Analysis of the alpha-like chain of HbM (92 of 141 residues) reveals a globin sequence closely related to the minor adult alpha D chain. Comparison of our sequence data with the nucleotide sequence of the alpha D globin gene suggests that a single gene encodes both the embryonic and adult alpha D globin polypeptides. We discuss the structure, possible function, and evolution of the HbM globin chains
Complete amino acid sequence of the major early embryonic beta-like globin in chickens
The rho globin is the major beta-like chain found in 5-day-old chick embryos. In association with two unique early embryonic alpha-like globins, it forms the two major hemoglobins of early chick development. This paper presents the complete amino acid sequence of the rho globin. There are no amino acid differences between the rho chain and the adult chicken beta chain at known Bohr effect or organophosphate-binding positions, and there are only 19 differences altogether. The rho globin ought to be functionally equivalent to the adult chicken beta globin. Since the adult and embryonic chains are very similar in sequence, they may be products of a relatively recent gene duplication in the chicken beta globin gene family. The possibility of a gene correction event is discussed
Amino acid sequences of the epsilon and alpha E globins of HbE, a minor early embryonic hemoglobin of the chicken
We have determined amino acid sequences for the alpha-like and beta- like globin components of HbE, one of the two minor hemoglobins in early chick embryos. The complete primary structure of the epsilon chain differs at 18 positions from the adult chicken beta globin, but there are no changes in heme-binding residues, alpha 1 beta 2 contact positions, or allosteric regulatory sites. By amino acid sequence analysis, we have identified a new alpha-like globin that we have called alpha E. The alpha E globin chain differs from the major adult alpha A chain at 22 amino acid positions. This paper discusses the structural and implied functional characteristics of these globins and presents hypotheses regarding the possible role of minor embryonic hemoglobins
The state of the Martian climate
60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes
State of the climate in 2013
In 2013, the vast majority of the monitored climate variables reported here maintained trends established in recent decades. ENSO was in a neutral state during the entire year, remaining mostly on the cool side of neutral with modest impacts on regional weather patterns around the world. This follows several years dominated by the effects of either La Niña or El Niño events. According to several independent analyses, 2013 was again among the 10 warmest years on record at the global scale, both at the Earths surface and through the troposphere. Some regions in the Southern Hemisphere had record or near-record high temperatures for the year. Australia observed its hottest year on record, while Argentina and New Zealand reported their second and third hottest years, respectively. In Antarctica, Amundsen-Scott South Pole Station reported its highest annual temperature since records began in 1957. At the opposite pole, the Arctic observed its seventh warmest year since records began in the early 20th century. At 20-m depth, record high temperatures were measured at some permafrost stations on the North Slope of Alaska and in the Brooks Range. In the Northern Hemisphere extratropics, anomalous meridional atmospheric circulation occurred throughout much of the year, leading to marked regional extremes of both temperature and precipitation. Cold temperature anomalies during winter across Eurasia were followed by warm spring temperature anomalies, which were linked to a new record low Eurasian snow cover extent in May. Minimum sea ice extent in the Arctic was the sixth lowest since satellite observations began in 1979. Including 2013, all seven lowest extents on record have occurred in the past seven years. Antarctica, on the other hand, had above-average sea ice extent throughout 2013, with 116 days of new daily high extent records, including a new daily maximum sea ice area of 19.57 million km2 reached on 1 October. ENSO-neutral conditions in the eastern central Pacific Ocean and a negative Pacific decadal oscillation pattern in the North Pacific had the largest impacts on the global sea surface temperature in 2013. The North Pacific reached a historic high temperature in 2013 and on balance the globally-averaged sea surface temperature was among the 10 highest on record. Overall, the salt content in nearsurface ocean waters increased while in intermediate waters it decreased. Global mean sea level continued to rise during 2013, on pace with a trend of 3.2 mm yr-1 over the past two decades. A portion of this trend (0.5 mm yr-1) has been attributed to natural variability associated with the Pacific decadal oscillation as well as to ongoing contributions from the melting of glaciers and ice sheets and ocean warming. Global tropical cyclone frequency during 2013 was slightly above average with a total of 94 storms, although the North Atlantic Basin had its quietest hurricane season since 1994. In the Western North Pacific Basin, Super Typhoon Haiyan, the deadliest tropical cyclone of 2013, had 1-minute sustained winds estimated to be 170 kt (87.5 m s-1) on 7 November, the highest wind speed ever assigned to a tropical cyclone. High storm surge was also associated with Haiyan as it made landfall over the central Philippines, an area where sea level is currently at historic highs, increasing by 200 mm since 1970. In the atmosphere, carbon dioxide, methane, and nitrous oxide all continued to increase in 2013. As in previous years, each of these major greenhouse gases once again reached historic high concentrations. In the Arctic, carbon dioxide and methane increased at the same rate as the global increase. These increases are likely due to export from lower latitudes rather than a consequence of increases in Arctic sources, such as thawing permafrost. At Mauna Loa, Hawaii, for the first time since measurements began in 1958, the daily average mixing ratio of carbon dioxide exceeded 400 ppm on 9 May. The state of these variables, along with dozens of others, and the 2013 climate conditions of regions around the world are discussed in further detail in this 24th edition of the State of the Climate series. © 2014, American Meteorological Society. All rights reserved
Discovery of novel heart rate-associated loci using the Exome Chip
Resting heart rate is a heritable trait, and an increase in heart rate is associated with increased mortality risk. Genome-wide association study analyses have found loci associated with resting heart rate, at the time of our study these loci explained 0.9% of the variation. This study aims to discover new genetic loci associated with heart rate from Exome Chip meta-analyses.
Heart rate was measured from either elecrtrocardiograms or pulse recordings. We meta-analysed heart rate association results from 104 452 European-ancestry individuals from 30 cohorts, genotyped using the Exome Chip. Twenty-four variants were selected for follow-up in an independent dataset (UK Biobank, N = 134 251). Conditional and gene-based testing was undertaken, and variants were investigated with bioinformatics methods.
We discovered five novel heart rate loci, and one new independent low-frequency non-synonymous variant in an established heart rate locus (KIAA1755). Lead variants in four of the novel loci are non-synonymous variants in the genes C10orf71, DALDR3, TESK2 and SEC31B. The variant at SEC31B is significantly associated with SEC31B expression in heart and tibial nerve tissue. Further candidate genes were detected from long-range regulatory chromatin interactions in heart tissue (SCD, SLF2 and MAPK8). We observed significant enrichment in DNase I hypersensitive sites in fetal heart and lung. Moreover, enrichment was seen for the first time in human neuronal progenitor cells (derived from embryonic stem cells) and fetal muscle samples by including our novel variants.
Our findings advance the knowledge of the genetic architecture of heart rate, and indicate new candidate genes for follow-up functional studies
A flow platform for degradation-free CuAAC bioconjugation
We thank Vapourtec for the copper reactors, the EPSRC UK National Mass Spectrometry Facility at Swansea University for analyses, the University of Strathclyde for PhD studentship (M.Z.C.H.), the Leverhulme Trust for a postdoctoral fellowship (L.F.R.; grant no. RPG-2014-001), and the BBSRC for funding (grant nos. BB/R006857/1, BB/N016378/1).The Cu-catalyzed azide-alkyne cycloaddition (CuAAC) reaction is a cornerstone method for the ligation of biomolecules. However, undesired Cu-mediated oxidation and Cu-contamination in bioconjugates limits biomedical utility. Here, we report a generic CuAAC flow platform for the rapid, robust, and broad-spectrum formation of discrete triazole bioconjugates. This process leverages an engineering problem to chemical advantage: solvent-mediated Cu pipe erosion generates ppm levels of Cu in situ under laminar flow conditions. This is sufficient to catalyze the CuAAC reaction of small molecule alkynes and azides, fluorophores, marketed drug molecules, peptides, DNA, and therapeutic oligonucleotides. This flow approach, not replicated in batch, operates at ambient temperature and pressure, requires short residence times, avoids oxidation of sensitive functional groups, and produces products with very low ppm Cu contamination.Publisher PDFPeer reviewe
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