711 research outputs found
Rapid Normalization of Epidermal Integrin Expression After Allografting of Human Keratinocytes
Allogeneic keratinocyte grafts have beneficial effects on skin wounds, but the underlying interactions between graft and woundbed remain to be explored in detail. The epidermal integrins play a pivotal role in mediating cell-to-cell and cell-to-matrix interactions. In unwounded epidermis, α2ÎČ1-, α3ÎČ1-, α6ÎČ4-, α5ÎČ1-, and αvÎČ5-integrins are confined to basal cells. During healing of incisional wounds, these integrins are also expressed in suprabasal cells, where they remain detectable even after epidermal integrity is fully reestablished. We examined the integrin subunits α2, α3, α6, α5, and αv in partial thickness burn wounds grafted with allogeneic keratinocytes and asked whether the effect of allogeneic keratinocyte grafts, i.e., fast reepithelialization, is reflected by an accelerated reversion to a normal integrin pattern. Biopsies were taken after wound debridement before grafting and 10 d after transplantation. After 10 d, a stratified epidermis had developed in all cases and integrins were mainly restricted to the basal cell layer of the neo-epidermis. α2-, α3-, α6-, and αv-subunits were present at basal and/or lateral cell borders, duplicating the integrin pattern in normal epidermis. The findings indicate that grafting accelerates the shift of the epidermis from an inflammatory to a regenerative state, as reflected by the reversion of the integrin pattern from a âspread-and-migrateâ to the âsteady-stateâ phenotype
Time- and temperature-dependent postmortem concentration changes of the (synthetic) cannabinoids JWH-210, RCS-4, as well as â9-tetrahydrocannabinol following pulmonary administration to pigs
In forensic toxicology, interpretation of postmortem (PM) drug concentrations might be complicated due to the lack of data concerning drug stability or PM redistribution (PMR). Regarding synthetic cannabinoids (SC), only sparse data are available, which derived from single case reports without any knowledge of dose and time of consumption. Thus, a controlled pig toxicokinetic study allowing for examination of PMR of SC was performed. Twelve pigs received a pulmonary dose of 200 ”g/kg BW each of 4-ethylnaphthalene-1-yl-(1-pentylindole-3-yl)methanone (JWH-210), 2-(4-methoxyphenyl)-1-(1-pentyl-indole-3-yl)methanone (RCS-4), and Î9-tetrahydrocannabinol via an ultrasonic nebulizer. Eight hours after, the pigs were put to death with T61 and specimens of relevant tissues and body fluids were collected. Subsequently, the animals were stored at room temperature (nâ=â6) or 4 °C (nâ=â6) and further samples were collected after 24, 48, and 72 h each. Concentrations were determined following enzymatic cleavage and solid-phase extraction by liquid-chromatography tandem mass spectrometry applying the standard addition approach. High concentrations of the parent compounds were observed in lung, liver, kidney and bile fluid/duodenum content as well as brain. HO-RCS-4 was the most prevalent metabolite detected in PM specimens. In general, changes of PM concentrations were found in every tissue and body fluid depending on the PM interval as well as storage temperature
Evidence of discrete yellowfin tuna (Thunnus albacares) populations demands rethink of management for this globally important resource
Tropical tuna fisheries are central to food security and economic development of many regions of the world. Contemporary population assessment and management generally assume these fisheries exploit a single mixed spawning population, within ocean basins. To date population genetics has lacked the required power to conclusively test this assumption. Here we demonstrate heterogeneous population structure among yellowfin tuna sampled at three locations across the Pacific Ocean (western, central, and eastern) via analysis of double digest restriction-site associated DNA using Next Generation Sequencing technology. The differences among locations are such that individuals sampled from one of the three regions examined can be assigned with close to 100% accuracy demonstrating the power of this approach for providing practical markers for fishery independent verification of catch provenance in a way not achieved by previous techniques. Given these results, an extended pan-tropical survey of yellowfin tuna using this approach will not only help combat the largest threat to sustainable fisheries (i.e. illegal, unreported, and unregulated fishing) but will also provide a basis to transform current monitoring, assessment, and management approaches for this globally significant species
Comparison of in vitro and in vivo models for the elucidation of metabolic patterns of 7-azaindole-derived synthetic cannabinoids exemplified using cumyl-5F-P7AICA
Due to the dynamic market involving synthetic cannabinoids (SCs), the determination of analytical targets is challenging in clinical and forensic toxicology. SCs usually undergo extensive metabolism, and therefore their main metabolites must be identified for the detection in biological matrices, particularly in urine. Controlled human studies are usually not possible for ethical reasons; thus, alternative models must be used. The aim of this work was to predict the in vitro and in vivo metabolic patterns of 7âazaindoleâderived SCs using 1â(5âfluoropentyl)âNâ(2âphenylpropanâ2âyl)â1Hâpyrollo[2,3âb]pyridinâ3âcarboxamide (cumylâ5FâP7AICA) as an example. Different in vitro (pooled human liver S9 fraction, pooled human liver microsomes, and pig liver microsomes) and in vivo (rat and pig) systems were compared. Monooxygenase isoenzymes responsible for the most abundant phase I steps, namely oxidative defluorination (OF) followed by carboxylation, monohydroxylation, and ketone formation, were identified. In both in vivo models, OF/carboxylation and Nâdealkylation/monohydroxylation/sulfation could be detected. Regarding pHS9 and pig urine, monohydroxylation/sulfation or glucuronidation was also abundant. Furthermore, the parent compound could still be detected in all models. Initial monooxygenase activity screening revealed the involvement of CYP2C19, CYP3A4, and CYP3A5. Therefore, in addition to the parent compound, the OF/carboxylated and monohydroxylated (and sulfated or glucuronidated) metabolites can be recommended as urinary targets. In comparison to literature, the pig model predicts best the human metabolic pattern of cumylâ5FâP7AICA. Furthermore, the pig model should be suitable to mirror the timeâdependent excretion pattern of parent compounds and metabolites
Is adipose tissue suitable for detection of (synthetic) cannabinoids? A comparative study analyzing antemortem and postmortem specimens following pulmonary administration of JWH-210, RCS-4, as well as â9-tetrahydrocannabinol to pigs
Examining fatal poisonings, chronic exposure may be refected by the concentration in tissues known for long-term storage
of drugs. Î9-tetrahydrocannabinol (THC) persists in adipose tissue (AT), but sparse data on synthetic cannabinoids (SC) are
available. Thus, a controlled pig study evaluating antemortem (AM) disposition and postmortem (PM) concentration changes
of the SC 4-ethylnaphthalene-1-yl-(1-pentylindole-3-yl)methanone (JWH-210) and 2-(4-methoxyphenyl)-1-(1-pentyl-indole3-yl)methanone (RCS-4) as well as THC in AT was performed. The drugs were administered pulmonarily (200 ”g/kg body
weight) to twelve pigs. Subcutaneous (s.c.) AT specimens were collected after 15 and 30 min and then hourly up to 8 h.
At the end, pigs were sacrifced and s.c., perirenal, and dorsal AT specimens were collected. The carcasses were stored at
room temperature (RT; n=6) or 4 °C (n=6) and specimens were collected after 24, 48, and 72 h. After homogenization in
acetonitrile and standard addition, LCâMS/MS was performed. Maximum concentrations were reached 0.5â2 h after administration amounting to 21±13 ng/g (JWH-210), 24±13 ng/g (RCS-4), and 22±20 ng/g (THC) and stayed at a plateau level.
Regarding the metabolites, very low concentrations of N-hydroxypentyl-RCS-4 (HO-RCS-4) were detected from 0.5 to 8 h.
PM concentrations of parent compounds did not change signifcantly (p>0.05) over time under both storage conditions.
Concentrations of HO-RCS-4 signifcantly (p<0.05) increased in perirenal AT during storage at RT. These results suggest a
rapid distribution and persistence in s.c. AT. Furthermore, AT might be resistant to PM redistribution of parent compounds.
However, signifcant PM increases of metabolite concentrations might be considered in perirenal AT
Toxicokinetics of U-47700, tramadol, and their main metabolites in pigs following intravenous administration: is a multiple species allometric scaling approach useful for the extrapolation of toxicokinetic parameters to humans?
New synthetic opioids (NSOs) pose a public health concern since their emergence on the illicit drug market and are gaining increasing importance in forensic toxicology. Like many other new psychoactive substances, NSOs are consumed without any preclinical safety data or any knowledge on toxicokinetic (TK) data. Due to ethical reasons, controlled human TK studies cannot be performed for the assessment of these relevant data. As an alternative animal experimental approach, six pigs per drug received a single intravenous dose of 100 ”g/kg body weight (BW) of U-47700 or 1000 ”g/kg BW of tramadol to evaluate whether this species is suitable to assess the TK of NSOs. The drugs were determined in serum and whole blood using a fully validated method based on solid-phase extraction and LCâMS/MS. The concentrationâtime profiles and a population (pop) TK analysis revealed that a three-compartment model best described the TK data of both opioids. Central volumes of distribution were 0.94 L/kg for U-47700 and 1.25 L/kg for tramadol and central (metabolic) clearances were estimated at 1.57 L/h/kg and 1.85 L/h/kg for U-47700 and tramadol, respectively. The final popTK model parameters for pigs were upscaled via allometric scaling techniques. In comparison to published human data, concentrationâtime profiles for tramadol could successfully be predicted with single species allometric scaling. Furthermore, possible profiles for U-47700 in humans were simulated. The findings of this study indicate that unlike a multiple species scaling approach, pigs in conjunction with TK modeling are a suitable tool for the assessment of TK data of NSOs and the prediction of human TK data
Interferometric diameters of five evolved intermediate-mass planet-hosting stars measured with PAVO at the CHARA Array
Debate over the planet occurrence rates around intermediate-mass stars has hinged on the accurate determination of masses of evolved stars, and has been exacerbated by a paucity of reliable, directly measured fundamental properties for these stars. We present long-baseline optical interferometry of five evolved intermediate-mass (âŒâ1.5âMâ) planet-hosting stars using the PAVO beam combiner at the CHARA Array, which we combine with bolometric flux measurements and parallaxes to determine their radii and effective temperatures. We measured the radii and effective temperatures of 6âLyncis (5.12 ± 0.16âRâ, 4949 ± 58âK), 24âSextantis (5.49 ± 0.18âRâ, 4908 ± 65âK), ÎșâCoronaeâBorealis (4.77 ± 0.07âRâ, 4870 ± 47âK), HRâ6817 (4.45 ± 0.08âRâ, 5013 ± 59âK), and HRâ8461 (4.91 ± 0.12âRâ, 4950 ± 68âK). We find disagreements of typically 15ââperâcent in angular diameter and âŒ200âK in temperature compared to interferometric measurements in the literature, yet good agreement with spectroscopic and photometric temperatures, concluding that the previous interferometric measurements may have been affected by systematic errors exceeding their formal uncertainties. Modelling based on BaSTI isochrones using various sets of asteroseismic, spectroscopic, and interferometric constraints tends to favour slightly (âŒ15ââperâcent) lower masses than generally reported in the literature.Funding for the Stellar Astrophysics Centre is provided by The
Danish National Research Foundation. The research was supported
by the ASTERISK project (ASTERoseismic Investigations with
SONG and Kepler) funded by the European Research Council
(Grant agreement no.: 267864). TRW and VSA acknowledge the support of the Villum Foundation (research grant 10118). DH acknowledges
support by the Australian Research Councilâs Discovery
Projects funding scheme (project number DE140101364) and
support by the NASA Grant NNX14AB92G issued through the
Kepler Participating Scientist Program. LC is supported by the
Australian Research Council Future Fellowship FT160100402. MJI
was supported by the Australian Research Council Future Fellowship
FT130100235. Parts of this research were conducted by the
Australian Research Council Centre of Excellence for All Sky Astrophysics
in 3 Dimensions (ASTRO 3D), through project number
CE170100013
Nuclear myosin VI maintains replication fork stability
The actin cytoskeleton is of fundamental importance for cellular structure and plasticity. However, abundance and function of filamentous actin in the nucleus are still controversial. Here we show that the actin-based molecular motor myosin VI contributes to the stabilization of stalled or reversed replication forks. In response to DNA replication stress, myosin VI associates with stalled replication intermediates and cooperates with the AAA ATPase Werner helicase interacting protein 1 (WRNIP1) in protecting these structures from DNA2-mediated nucleolytic attack. Using functionalized affinity probes to manipulate myosin VI levels in a compartment-specific manner, we provide evidence for the direct involvement of myosin VI in the nucleus and against a contribution of the abundant cytoplasmic pool during the replication stress response
Unraveling the directional link between adiposity and inflammation: a bidirectional mendelian randomization approach
<b>Context</b>: Associations between adiposity and circulating inflammation markers are assumed to be causal, although the direction of the relationship has not been proven.
<b>Objective</b>: The aim of the study was to explore the causal direction of the relationship between adiposity and inflammation using a bidirectional Mendelian randomization approach.
<b>Methods</b>: In the PROSPER study of 5804 elderly patients, we related C-reactive protein (CRP) single nucleotide polymorphisms (SNPs) (rs1800947 and rs1205) and adiposity SNPs (FTO and MC4R) to body mass index (BMI) as well as circulating levels of CRP and leptin. We gave each individual two allele scores ranging from zero to 4, counting each pair of alleles related to CRP levels or BMI.
<b>Results</b>: With increasing CRP allele score, there was a stepwise decrease in CRP levels (P for trend < 0.0001) and a 1.98 mg/liter difference between extremes of the allele score distribution, but there was no associated change in BMI or leptin levels (P â„ 0.89). By contrast, adiposity allele score was associated with 1) an increase in BMI (1.2 kg/m2 difference between extremes; P for trend 0.002); 2) an increase in circulating leptin (5.77 ng/ml difference between extremes; P for trend 0.0027); and 3) increased CRP levels (1.24 mg/liter difference between extremes; P for trend 0.002).
<b>Conclusions</b>: Greater adiposity conferred by FTO and MC4R SNPs led to higher CRP levels, with no evidence for any reverse pathway. Future studies should extend our findings to other circulating inflammatory parameters. This study illustrates the potential power of Mendelian randomization to dissect directions of causality between intercorrelated metabolic factors
Validation of the Exoplanet Kepler-21b using PAVO/CHARA Long-Baseline Interferometry
We present long-baseline interferometry of the Kepler exoplanet host star
HD179070 (Kepler-21) using the PAVO beam combiner at the CHARA Array. The
visibility data are consistent with a single star and exclude stellar
companions at separations ~1-1000 mas (~ 0.1-113 AU) and contrasts < 3.5
magnitudes. This result supports the validation of the 1.6 R_{earth} exoplanet
Kepler-21b by Howell et al. (2012) and complements the constraints set by
adaptive optics imaging, speckle interferometry, and radial velocity
observations to rule out false-positives due to stellar companions. We conclude
that long-baseline interferometry has strong potential to validate transiting
extrasolar planets, particularly for future projects aimed at brighter stars
and for host stars where radial velocity follow-up is not available.Comment: 5 pages, 3 figures, accepted for publication in MNRAS Letters; v2:
minor changes added in proo
- âŠ