Highlights ► Attenuation of GRK2 enhances inflammatory mediator-induced hyperalgesia. ► The enhanced nociceptor function persists after recovery of GRK2 protein expression. ► The phenomenon takes ...place downstream the GPCRs at which inflammatory mediators act. ► The mechanism involved is distinct from that described for hyperalgesic priming.
Acetyl-coenzyme A (acetyl-CoA) formed within the plastid is the precursor for the biosynthesis of fatty acids and, through them, a range of important biomolecules. The source of acetyl-CoA in the ...plastid is not known, but two enzymes are thought to be involved: acetyl-CoA synthetase and plastidic pyruvate dehydrogenase. To determine the importance of these two enzymes in synthesizing acetyl-CoA during lipid accumulation in developing Arabidopsis seeds, we isolated cDNA clones for acetyl-CoA synthetase and for the ptE1α- and ptE1β-subunits of plastidic pyruvate dehydrogenase. To our knowledge, this is the first reported acetyl-CoA synthetase sequence from a plant source. The Arabidopsis acetyl-CoA synthetase preprotein has a calculated mass of 76,678 D, an apparent plastid targeting sequence, and the mature protein is a monomer of 70 to 72 kD. During silique development, the spatial and temporal patterns of the ptE1β mRNA level are very similar to those of the mRNAs for the plastidic heteromeric acetyl-CoA carboxylase subunits. The pattern of ptE1β mRNA accumulation strongly correlates with the formation of lipid within the developing embryo. In contrast, the level of mRNA for acetyl-CoA synthetase does not correlate in time and space with lipid accumulation. The highest level of accumulation of the mRNA for acetyl-CoA synthetase during silique development is within the funiculus. These mRNA data suggest a predominant role for plastidic pyruvate dehydrogenase in acetyl-CoA formation during lipid synthesis in seeds.
The discovery that peroxisome proliferator-activated receptor (PPAR)-gamma was the molecular target of the thiazolidinedione class of antidiabetic agents suggested a key role for PPAR-gamma in the ...regulation of carbohydrate and lipid metabolism. Through the use of high-throughput biochemical assays, GW1929, a novel N-aryl tyrosine activator of human PPAR-gamma, was identified. Chronic oral administration of GW1929 or troglitazone to Zucker diabetic fatty (ZDF) rats resulted in dose-dependent decreases in daily glucose, free fatty acid, and triglyceride exposure compared with pretreatment values, as well as significant decreases in glycosylated hemoglobin. Whole body insulin sensitivity, as determined by the euglycemic-hyperinsulinemic clamp technique, was significantly increased in treated animals. Comparison of the magnitude of glucose lowering as a function of serum drug concentrations showed that GW1929 was 2 orders of magnitude more potent than troglitazone in vivo. These data were consistent with the relative in vitro potencies of GW1929 and troglitazone. Isolated perfused pancreas studies performed at the end of the study confirmed that pancreata from vehicle-treated rats showed no increase in insulin secretion in response to a step change in glucose from 3 to 10 mmol/l. In contrast, pancreata from animals treated with GW1929 showed a first- and second-phase insulin secretion pattern. Consistent with the functional data from the perfusion experiments, animals treated with the PPAR-gamma agonist had more normal islet architecture with preserved insulin staining compared with vehicle-treated ZDF rats. This is the first demonstration of in vivo efficacy of a novel nonthiazolidinedione identified as a high-affinity ligand for human PPAR-gamma. The increased potency of GW1929 compared with troglitazone both in vitro and in vivo may translate into improved clinical efficacy when used as monotherapy in type 2 diabetic patients. In addition, the significant improvement in daily meal tolerance may impact cardiovascular risk factor management in these patients.
APOE ɛ4, the most significant genetic risk factor for Alzheimer disease (AD), may mask effects of other loci. We re-analyzed genome-wide association study (GWAS) data from the International Genomics ...of Alzheimer's Project (IGAP) Consortium in APOE ɛ4+ (10 352 cases and 9207 controls) and APOE ɛ4- (7184 cases and 26 968 controls) subgroups as well as in the total sample testing for interaction between a single-nucleotide polymorphism (SNP) and APOE ɛ4 status. Suggestive associations (P<1 × 10(-4)) in stage 1 were evaluated in an independent sample (stage 2) containing 4203 subjects (APOE ɛ4+: 1250 cases and 536 controls; APOE ɛ4-: 718 cases and 1699 controls). Among APOE ɛ4- subjects, novel genome-wide significant (GWS) association was observed with 17 SNPs (all between KANSL1 and LRRC37A on chromosome 17 near MAPT) in a meta-analysis of the stage 1 and stage 2 data sets (best SNP, rs2732703, P=5·8 × 10(-9)). Conditional analysis revealed that rs2732703 accounted for association signals in the entire 100-kilobase region that includes MAPT. Except for previously identified AD loci showing stronger association in APOE ɛ4+ subjects (CR1 and CLU) or APOE ɛ4- subjects (MS4A6A/MS4A4A/MS4A6E), no other SNPs were significantly associated with AD in a specific APOE genotype subgroup. In addition, the finding in the stage 1 sample that AD risk is significantly influenced by the interaction of APOE with rs1595014 in TMEM106B (P=1·6 × 10(-7)) is noteworthy, because TMEM106B variants have previously been associated with risk of frontotemporal dementia. Expression quantitative trait locus analysis revealed that rs113986870, one of the GWS SNPs near rs2732703, is significantly associated with four KANSL1 probes that target transcription of the first translated exon and an untranslated exon in hippocampus (P ⩽ 1.3 × 10(-8)), frontal cortex (P ⩽ 1.3 × 10(-9)) and temporal cortex (P⩽1.2 × 10(-11)). Rs113986870 is also strongly associated with a MAPT probe that targets transcription of alternatively spliced exon 3 in frontal cortex (P=9.2 × 10(-6)) and temporal cortex (P=2.6 × 10(-6)). Our APOE-stratified GWAS is the first to show GWS association for AD with SNPs in the chromosome 17q21.31 region. Replication of this finding in independent samples is needed to verify that SNPs in this region have significantly stronger effects on AD risk in persons lacking APOE ɛ4 compared with persons carrying this allele, and if this is found to hold, further examination of this region and studies aimed at deciphering the mechanism(s) are warranted.
Highlights • In male rats, κ-opioids produce analgesia, followed by anti-analgesia. • Low-dose naloxone blocked anti-analgesia but not analgesia. • Nociceptin/orphanin FQ (NOP) antagonists also ...blocked anti-analgesia. • Selective kappa antagonist nor-BNI did not block nalbuphine-induced anti-analgesia. • Clinically used agonist–antagonists act at NOP receptors to produce anti-analgesia.
A fundamental assumption in invasion biology is that most invasive species exhibit enhanced performance in their introduced range relative to their home ranges. This idea has given rise to numerous ...hypotheses explaining "invasion success" by virtue of altered ecological and evolutionary pressures. There are surprisingly few data, however, testing the underlying assumption that the performance of introduced populations, including organism size, reproductive output, and abundance, is enhanced in their introduced compared to their native range. Here, we combined data from published studies to test this hypothesis for 26 plant and 27 animal species that are considered to be invasive. On average, individuals of these 53 species were indeed larger, more fecund, and more abundant in their introduced ranges. The overall mean, however, belied significant variability among species, as roughly half of the investigated species (
N
= 27) performed similarly when compared to conspecific populations in their native range. Thus, although some invasive species are performing better in their new ranges, the pattern is not universal, and just as many are performing largely the same across ranges.
Nowadays, progress in the determination of three‐dimensional macromolecular structures from diffraction images is achieved partly at the cost of increasing data volumes. This is due to the deployment ...of modern high‐speed, high‐resolution detectors, the increased complexity and variety of crystallographic software, the use of extensive databases and high‐performance computing. This limits what can be accomplished with personal, offline, computing equipment in terms of both productivity and maintainability. There is also an issue of long‐term data maintenance and availability of structure‐solution projects as the links between experimental observations and the final results deposited in the PDB. In this article, CCP4 Cloud, a new front‐end of the CCP4 software suite, is presented which mitigates these effects by providing an online, cloud‐based environment for crystallographic computation. CCP4 Cloud was developed for the efficient delivery of computing power, database services and seamless integration with web resources. It provides a rich graphical user interface that allows project sharing and long‐term storage for structure‐solution projects, and can be linked to data‐producing facilities. The system is distributed with the CCP4 software suite version 7.1 and higher, and an online publicly available instance of CCP4 Cloud is provided by CCP4.
The paper describes CCP4 Cloud, an online system for macromolecular structure determination based on the CCP4 software suite.
The second phase of the Fifth International Ice Nucleation Workshop (FIN-02)
involved the gathering of a large number of researchers at the Karlsruhe
Institute of Technology's Aerosol Interactions ...and Dynamics of the Atmosphere
(AIDA) facility to promote characterization and understanding of ice
nucleation measurements made by a variety of methods used worldwide.
Compared to the previous workshop in 2007, participation was doubled,
reflecting a vibrant research area. Experimental methods involved sampling of
aerosol particles by direct processing ice nucleation measuring systems from
the same volume of air in separate experiments using different ice nucleating
particle (INP) types, and collections of aerosol particle samples onto
filters or into liquid for sharing amongst measurement techniques that
post-process these samples. In this manner, any errors introduced by
differences in generation methods when samples are shared across laboratories
were mitigated. Furthermore, as much as possible, aerosol particle size
distribution was controlled so that the size limitations of different methods
were minimized. The results presented here use data from the workshop to
assess the comparability of immersion freezing measurement methods activating
INPs in bulk suspensions, methods that activate INPs in condensation and/or
immersion freezing modes as single particles on a substrate, continuous flow
diffusion chambers (CFDCs) directly sampling and processing particles well
above water saturation to maximize immersion and subsequent freezing of
aerosol particles, and expansion cloud chamber simulations in which liquid
cloud droplets were first activated on aerosol particles prior to freezing.
The AIDA expansion chamber measurements are expected to be the closest
representation to INP activation in atmospheric cloud parcels in these
comparisons, due to exposing particles freely to adiabatic cooling. The different particle types used as INPs included the minerals illite NX and
potassium feldspar (K-feldspar), two natural soil dusts representative of arable sandy loam
(Argentina) and highly erodible sandy dryland (Tunisia) soils, respectively,
and a bacterial INP (Snomax®). Considered
together, the agreement among post-processed immersion freezing measurements
of the numbers and fractions of particles active at different temperatures
following bulk collection of particles into liquid was excellent, with
possible temperature uncertainties inferred to be a key factor in determining
INP uncertainties. Collection onto filters for rinsing versus directly into
liquid in impingers made little difference. For methods that activated
collected single particles on a substrate at a controlled humidity at or
above water saturation, agreement with immersion freezing methods was good in
most cases, but was biased low in a few others for reasons that have not been
resolved, but could relate to water vapor competition effects. Amongst
CFDC-style instruments, various factors requiring (variable) higher
supersaturations to achieve equivalent immersion freezing activation dominate
the uncertainty between these measurements, and for comparison with bulk
immersion freezing methods. When operated above water saturation to include
assessment of immersion freezing, CFDC measurements often measured at or
above the upper bound of immersion freezing device measurements, but often
underestimated INP concentration in comparison to an immersion freezing
method that first activates all particles into liquid droplets prior to
cooling (the PIMCA-PINC device, or Portable Immersion Mode Cooling chAmber–Portable Ice Nucleation Chamber), and typically slightly underestimated INP
number concentrations in comparison to cloud parcel expansions in the AIDA
chamber; this can be largely mitigated when it is possible to raise the
relative humidity to sufficiently high values in the CFDCs, although this is
not always possible operationally. Correspondence of measurements of INPs among direct sampling and
post-processing systems varied depending on the INP type. Agreement was best
for Snomax® particles in the temperature regime
colder than −10 ∘C, where their ice nucleation activity is nearly
maximized and changes very little with temperature. At temperatures warmer than
−10 ∘C, Snomax® INP measurements (all
via freezing of suspensions) demonstrated discrepancies consistent with
previous reports of the instability of its protein aggregates that appear to
make it less suitable as a calibration INP at these temperatures. For
Argentinian soil dust particles, there was excellent agreement across all
measurement methods; measures ranged within 1 order of magnitude for INP
number concentrations, active fractions and calculated active site densities
over a 25 to 30 ∘C range and 5 to 8 orders of corresponding
magnitude change in number concentrations. This was also the case for all
temperatures warmer than −25 ∘C in Tunisian dust experiments. In
contrast, discrepancies in measurements of INP concentrations or active site
densities that exceeded 2 orders of magnitude across a broad range of temperature
measurements found at temperatures warmer than −25 ∘C in a previous study were
replicated for illite NX. Discrepancies also exceeded 2 orders of magnitude at
temperatures of −20 to −25 ∘C for potassium feldspar (K-feldspar), but these coincided
with the range of temperatures at which INP concentrations increase rapidly at
approximately an order of magnitude per 2 ∘C cooling for
K-feldspar. These few discrepancies did not outweigh the overall positive outcomes of the
workshop activity, nor the future utility of this data set or future similar
efforts for resolving remaining measurement issues. Measurements of the same
materials were repeatable over the time of the workshop and demonstrated
strong consistency with prior studies, as reflected by agreement of data
broadly with parameterizations of different specific or general (e.g., soil
dust) aerosol types. The divergent measurements of the INP activity of illite
NX by direct versus post-processing methods were not repeated for other
particle types, and the Snomax® data
demonstrated that, at least for a biological INP type, there is no expected
measurement bias between bulk collection and direct immediately processed
freezing methods to as warm as −10 ∘C. Since particle size ranges
were limited for this workshop, it can be expected that for atmospheric
populations of INPs, measurement discrepancies will appear due to the
different capabilities of methods for sampling the full aerosol size
distribution, or due to limitations on achieving sufficient water
supersaturations to fully capture immersion freezing in direct processing
instruments. Overall, this workshop presents an improved picture of present
capabilities for measuring INPs than in past workshops, and provides
direction toward addressing remaining measurement issues.
Medulloblastoma is the most common malignant brain tumor in children. It is thought to result from the transformation of granule cell precursors (GCPs) in the developing cerebellum, but little is ...known about the early stages of the disease. Here, we identify a pre-neoplastic stage of medulloblastoma in patched heterozygous mice, a model of the human disease. We show that pre-neoplastic cells are present in the majority of patched mutants, although only 16% of these mice develop tumors. Pre-neoplastic cells, like tumor cells, exhibit activation of the Sonic hedgehog pathway and constitutive proliferation. Importantly, they also lack expression of the wild-type patched allele, suggesting that loss of patched is an early event in tumorigenesis. Although pre-neoplastic cells resemble GCPs and tumor cells in many respects, they have a distinct molecular signature. Genes that mark the pre-neoplastic stage include regulators of migration, apoptosis and differentiation, processes crucial for normal development but previously unrecognized for their role in medulloblastoma. The identification and molecular characterization of pre-neoplastic cells provides insight into the early steps in medulloblastoma formation, and may yield important markers for early detection and therapy of this disease.
The Plateau-Rayleigh instability of a liquid column underlies a variety of fascinating phenomena that can be observed in everyday life. In contrast to the case of a free liquid cylinder, describing ...the evolution of a liquid layer on a solid fibre requires consideration of the solid-liquid interface. Here we revisit the Plateau-Rayleigh instability of a liquid coating a fibre by varying the hydrodynamic boundary condition at the fibre-liquid interface, from no slip to slip. Although the wavelength is not sensitive to the solid-liquid interface, we find that the growth rate of the undulations strongly depends on the hydrodynamic boundary condition. The experiments are in excellent agreement with a new thin-film theory incorporating slip, thus providing an original, quantitative and robust tool to measure slip lengths.
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