319 research outputs found
Identification and characterization of an acyl-CoA dehydrogenase from Pseudomonas putida KT2440 that shows preference towards medium to long chain length fatty acids
Diverse and elaborate pathways for nutrient utilization, as well as mechanisms to combat unfavourable nutrient conditions make Pseudomonas putida KT2440 a versatile micro-organism able to occupy a range of ecological niches. The fatty acid degradation pathway of P. putida is complex and correlated with biopolymer medium chain length polyhydroxyalkanoate (mcl-PHA) biosynthesis. Little is known about the second step of fatty acid degradation (beta-oxidation) in this strain. In silico analysis of its genome sequence revealed 21 putative acyl-CoA dehydrogenases (ACADs), four of which were functionally characterized through mutagenesis studies. Four mutants with insertionally inactivated ACADs (PP_1893, PP_2039, PP_2048 and PP_2437) grew and accumulated mcl-PHA on a range of fatty acids as the sole source of carbon and energy. Their ability to grow and accumulate biopolymer was differentially negatively affected on various fatty acids, in comparison to the wild-type strain. Inactive PP_2437 exhibited a pattern of reduced growth and PHA accumulation when fatty acids with lengths of 10 to 14 carbon chains were used as substrates. Recombinant expression and biochemical characterization of the purified protein allowed functional annotation in P. putida KT2440 as an ACAD showing clear preference for dodecanoyl-CoA ester as a substrate and optimum activity at 30 degrees C and pH 6.5-7
Cerebellar c9RAN proteins associate with clinical and neuropathological characteristics of C9ORF72 repeat expansion carriers.
Clinical and neuropathological characteristics associated with G4C2 repeat expansions in chromosome 9 open reading frame 72 (C9ORF72), the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia, are highly variable. To gain insight on the molecular basis for the heterogeneity among C9ORF72 mutation carriers, we evaluated associations between features of disease and levels of two abundantly expressed "c9RAN proteins" produced by repeat-associated non-ATG (RAN) translation of the expanded repeat. For these studies, we took a departure from traditional immunohistochemical approaches and instead employed immunoassays to quantitatively measure poly(GP) and poly(GA) levels in cerebellum, frontal cortex, motor cortex, and/or hippocampus from 55 C9ORF72 mutation carriers [12 patients with ALS, 24 with frontotemporal lobar degeneration (FTLD) and 19 with FTLD with motor neuron disease (FTLD-MND)]. We additionally investigated associations between levels of poly(GP) or poly(GA) and cognitive impairment in 15 C9ORF72 ALS patients for whom neuropsychological data were available. Among the neuroanatomical regions investigated, poly(GP) levels were highest in the cerebellum. In this same region, associations between poly(GP) and both neuropathological and clinical features were detected. Specifically, cerebellar poly(GP) levels were significantly lower in patients with ALS compared to patients with FTLD or FTLD-MND. Furthermore, cerebellar poly(GP) associated with cognitive score in our cohort of 15 patients. In the cerebellum, poly(GA) levels similarly trended lower in the ALS subgroup compared to FTLD or FTLD-MND subgroups, but no association between cerebellar poly(GA) and cognitive score was detected. Both cerebellar poly(GP) and poly(GA) associated with C9ORF72 variant 3 mRNA expression, but not variant 1 expression, repeat size, disease onset, or survival after onset. Overall, these data indicate that cerebellar abnormalities, as evidenced by poly(GP) accumulation, associate with neuropathological and clinical phenotypes, in particular cognitive impairment, of C9ORF72 mutation carriers
The early environment and the brain in adolescence
Prenatal and early postnatal adversities have been shown to be associated with brain development. However, we do not know how much of this association is confounded by genetics, nor whether the postnatal environment can moderate the impact of in utero adversity. This study used a monozygotic (MZ) twin design to assess (1) the association between birth weight (BW) and brain volume in adolescence, (2) the association between within-twin-pair BW discordance and brain volume discordance in adolescence, and (3) whether the association between BW and brain volume in adolescence is mediated or moderated by early negative maternal parenting behaviours. These associations were assessed in a sample of 108 MZ twins followed longitudinally since birth and scanned at age 15. The total grey matter (GM) and white matter (WM) volumes were obtained using the Diffeomorphic Anatomical Registration Through Exponentiated Lie Algebra (DARTEL) toolbox in the Statistical Parametric Mapping version 8 (SPM8). We found that the BW was significantly associated with the total GM and WM volumes, particularly in the superior frontal gyrus and thalamus. Within-twin-pair discordance in BW was also significantly associated with within-pair discordance in both the GM and the WM volumes, supporting the hypothesis that the specific in utero environment is associated with brain development independently of genetics. Early maternal hostile parenting behaviours and depressive symptoms were associated with total GM volume but not WM volume. Finally, greater early maternal hostility may moderate the association between the BW and GM volume in adolescence, since the positive association between the BW and total GM volume appeared stronger at higher levels of maternal hostility (trend). Together, these findings support the importance of the in utero and early environments for brain development
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Hyperpolarized<sup>13</sup>C-Pyruvate Metabolism as a Surrogate for Tumor Grade and Poor Outcome in Renal Cell Carcinoma—A Proof of Principle Study
Differentiating aggressive clear cell renal cell carcinoma (ccRCC) from indolent lesions is challenging using conventional imaging. This work prospectively compared the metabolic imaging phenotype of renal tumors using carbon-13 MRI following injection of hyperpolarized [1-13C]pyruvate (HP-13C-MRI) and validated these findings with histopathology. Nine patients with treatment-naïve renal tumors (6 ccRCCs, 1 liposarcoma, 1 pheochromocytoma, 1 oncocytoma) underwent pre-operative HP-13C-MRI and conventional proton (1H) MRI. Multi-regional tissue samples were collected using patient-specific 3D-printed tumor molds for spatial registration between imaging and molecular analysis. The apparent exchange rate constant (kPL) between 13C-pyruvate and 13C-lactate was calculated. Immunohistochemistry for the pyruvate transporter (MCT1) from 44 multi-regional samples, as well as associations between MCT1 expression and outcome in the TCGA-KIRC dataset, were investigated. Increasing kPL in ccRCC was correlated with increasing overall tumor grade (ρ = 0.92, p = 0.009) and MCT1 expression (r = 0.89, p = 0.016), with similar results acquired from the multi-regional analysis. Conventional 1H-MRI parameters did not discriminate tumor grades. The correlation between MCT1 and ccRCC grade was confirmed within a TCGA dataset (p < 0.001), where MCT1 expression was a predictor of overall and disease-free survival. In conclusion, metabolic imaging using HP-13C-MRI differentiates tumor aggressiveness in ccRCC and correlates with the expression of MCT1, a predictor of survival. HP-13C-MRI may non-invasively characterize metabolic phenotypes within renal cancer.</jats:p
MPLEx: a method for simultaneous pathogen inactivation and extraction of samples for multi-omics profiling
The continued emergence and spread of infectious agents is of great concern, and systems biology approaches to infectious disease research can advance our understanding of host–pathogen relationships and facilitate the development of new therapies and vaccines
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
High frequency DC-DC converter with co-packaged planar inductor and power IC
The paper introduces the trend of integration and miniaturization of power converters with potential for enhanced efficiency, form factor reduction and cost reduction. To demonstrate the concept of highly integrated switched mode power supply with integrated magnetic, a system-in-package DC-DC converter using a stacked co-packaging approach is developed. A system approach was taken to the design, and functional integration, using 3-D packaging for realizing a power supply in package solution (PwrSiP). The target integrated converter is capable of handling an input voltage of 5V and frequencies up to 40MHz. A DC-DC converter IC on a 0.35μm CMOS process was designed to meet this goal. In parallel with the IC design, technology development for on-silicon integrated micro-inductors was completed to achieve small-form factor and extremely low profile. A maximum measured efficiency of 83% and 78% was achieved on the stacked converter operating at 20MHz and 40MHz, respectively. The stacked approach showed a 30% area reduction compared to side-by-side implementation with external discrete inductor
Hyperpolarized 13C-Pyruvate Metabolism as a Surrogate for Tumor Grade and Poor Outcome in Renal Cell Carcinoma-A Proof of Principle Study.
Differentiating aggressive clear cell renal cell carcinoma (ccRCC) from indolent lesions is challenging using conventional imaging. This work prospectively compared the metabolic imaging phenotype of renal tumors using carbon-13 MRI following injection of hyperpolarized [1-13C]pyruvate (HP-13C-MRI) and validated these findings with histopathology. Nine patients with treatment-naïve renal tumors (6 ccRCCs, 1 liposarcoma, 1 pheochromocytoma, 1 oncocytoma) underwent pre-operative HP-13C-MRI and conventional proton (1H) MRI. Multi-regional tissue samples were collected using patient-specific 3D-printed tumor molds for spatial registration between imaging and molecular analysis. The apparent exchange rate constant (kPL) between 13C-pyruvate and 13C-lactate was calculated. Immunohistochemistry for the pyruvate transporter (MCT1) from 44 multi-regional samples, as well as associations between MCT1 expression and outcome in the TCGA-KIRC dataset, were investigated. Increasing kPL in ccRCC was correlated with increasing overall tumor grade (ρ = 0.92, p = 0.009) and MCT1 expression (r = 0.89, p = 0.016), with similar results acquired from the multi-regional analysis. Conventional 1H-MRI parameters did not discriminate tumor grades. The correlation between MCT1 and ccRCC grade was confirmed within a TCGA dataset (p < 0.001), where MCT1 expression was a predictor of overall and disease-free survival. In conclusion, metabolic imaging using HP-13C-MRI differentiates tumor aggressiveness in ccRCC and correlates with the expression of MCT1, a predictor of survival. HP-13C-MRI may non-invasively characterize metabolic phenotypes within renal cancer
The GALAH+ Survey : Third Data Release
© 2021 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1093/mnras/stab1242The ensemble of chemical element abundance measurements for stars, along with precision distances and orbit properties, provides high-dimensional data to study the evolution of the Milky Way. With this third data release of the Galactic Archaeology with HERMES (GALAH) survey, we publish 678 423 spectra for 588 571 mostly nearby stars (81.2% of stars are within 75 stellar clusters. We derive stellar parameters , , [Fe/H], , & using our modified version of the spectrum synthesis code Spectroscopy Made Easy (SME) and 1D MARCS model atmospheres. We break spectroscopic degeneracies in our spectrum analysis with astrometry from DR2 and photometry from 2MASS. We report abundance ratios [X/Fe] for 30 different elements (11 of which are based on non-LTE computations) covering five nucleosynthetic pathways. We describe validations for accuracy and precision, flagging of peculiar stars/measurements and recommendations for using our results. Our catalogue comprises 65% dwarfs, 34% giants, and 1% other/unclassified stars. Based on unflagged chemical composition and age, we find 62% young low-, 9% young high-, 27% old high-, and 2% stars with . Based on kinematics, 4% are halo stars. Several Value-Added-Catalogues, including stellar ages and dynamics, updated after eDR3, accompany this release and allow chrono-chemodynamic analyses, as we showcase.Peer reviewe
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