208 research outputs found
Log D<sub>7.4</sub> and plasma protein binding of synthetic cannabinoid receptor agonists and a comparison of experimental and predicted lipophilicity
The emergence of new synthetic cannabinoid receptor agonists (SCRAs) onto the illicit drugs market continues to cause harm, and the overall availability of physicochemical and pharmacokinetic data for new psychoactive substances is lacking. The lipophilicity of 23 SCRAs and the plasma protein binding (PPB) of 11 SCRAs was determined. Lipophilicity was determined using a validated chromatographic hydrophobicity index (CHI) log D method; tested SCRAs showed moderate to high lipophilicity, with experimental log D7.4 ranging from 2.48 (AB-FUBINACA) to 4.95 (4F-ABUTINACA). These results were also compared to in silico predictions generated using seven commercially available software packages and online tools (Canvas; ChemDraw; Gastroplus; MoKa; PreADMET; SwissADME; and XlogP). Licenced, dedicated software packages provided more accurate lipophilicity predictions than those which were free or had prediction as a secondary function; however, the latter still provided competitive estimates in most cases. PPB of tested SCRAs, as determined by equilibrium dialysis, was in the upper range of the lipophilicity scale, ranging from 90.8% (ADB-BUTINACA) to 99.9% (BZO-HEXOXIZID). The high PPB of these drugs may contribute to reduced rate of clearance and extended durations of pharmacological effects compared to lesser-bound SCRAs. The presented data improve understanding of the behaviour of these drugs in the body. Ultimately, similar data and predictions may be used in the prediction of the structure and properties of drugs yet to emerge on the illicit market
Exact vortex solutions in a CP^N Skyrme-Faddeev type model
We consider a four dimensional field theory with target space being CP^N
which constitutes a generalization of the usual Skyrme-Faddeev model defined on
CP^1. We show that it possesses an integrable sector presenting an infinite
number of local conservation laws, which are associated to the hidden
symmetries of the zero curvature representation of the theory in loop space. We
construct an infinite class of exact solutions for that integrable submodel
where the fields are meromorphic functions of the combinations (x^1+i x^2) and
(x^3+x^0) of the Cartesian coordinates of four dimensional Minkowski
space-time. Among those solutions we have static vortices and also vortices
with waves traveling along them with the speed of light. The energy per unity
of length of the vortices show an interesting and intricate interaction among
the vortices and waves.Comment: 21 pages, plain latex, no figure
Social determinants of adaptive and transformative responses to climate change
This is the author accepted manuscript. The final version is available from Nature Research via the DOI in this recordData availability:
Summary data that support the findings of this study are available within the paper and its Supplementary Information file. Raw ecological network data have been deposited in the Tropical Data Hub and can be accessed at https://doi.org/10.25903/5ecf39990a0bb. Raw social and social network data are available on request from the corresponding author with reasonable restrictions, as these data contain information that could compromise research participant privacy and consent.To cope effectively with the impacts of climate change, people will need to change existing practices or behaviours within existing social–ecological systems (adaptation) or enact more fundamental changes that can alter dominant social–ecological relationships and create new systems or futures (transformation). Here we use multilevel network modelling to examine how different domains of adaptive capacity—assets, flexibility, organization, learning, socio-cognitive constructs and agency—are related to adaptive and transformative actions. We find evidence consistent with an influence process in which aspects of social organization (exposure to others in social networks) encourage both adaptive and transformative actions among Papua New Guinean islanders experiencing climate change impacts. Adaptive and transformative actions are also related to social–ecological network structures between people and ecological resources that enable learning and the internalization of ecological feedbacks. Agency is also key, yet we show that while perceived power may encourage adaptations, it may discourage more transformative actions.Australian Research Council (ARC)U.S. National Science FoundationCGIA
Utilisation of an operative difficulty grading scale for laparoscopic cholecystectomy
Background
A reliable system for grading operative difficulty of laparoscopic cholecystectomy would standardise description of findings and reporting of outcomes. The aim of this study was to validate a difficulty grading system (Nassar scale), testing its applicability and consistency in two large prospective datasets.
Methods
Patient and disease-related variables and 30-day outcomes were identified in two prospective cholecystectomy databases: the multi-centre prospective cohort of 8820 patients from the recent CholeS Study and the single-surgeon series containing 4089 patients. Operative data and patient outcomes were correlated with Nassar operative difficultly scale, using Kendall’s tau for dichotomous variables, or Jonckheere–Terpstra tests for continuous variables. A ROC curve analysis was performed, to quantify the predictive accuracy of the scale for each outcome, with continuous outcomes dichotomised, prior to analysis.
Results
A higher operative difficulty grade was consistently associated with worse outcomes for the patients in both the reference and CholeS cohorts. The median length of stay increased from 0 to 4 days, and the 30-day complication rate from 7.6 to 24.4% as the difficulty grade increased from 1 to 4/5 (both p < 0.001). In the CholeS cohort, a higher difficulty grade was found to be most strongly associated with conversion to open and 30-day mortality (AUROC = 0.903, 0.822, respectively). On multivariable analysis, the Nassar operative difficultly scale was found to be a significant independent predictor of operative duration, conversion to open surgery, 30-day complications and 30-day reintervention (all p < 0.001).
Conclusion
We have shown that an operative difficulty scale can standardise the description of operative findings by multiple grades of surgeons to facilitate audit, training assessment and research. It provides a tool for reporting operative findings, disease severity and technical difficulty and can be utilised in future research to reliably compare outcomes according to case mix and intra-operative difficulty
Association of Transcription Factor Gene LMX1B with Autism
Multiple lines of evidence suggest a serotoninergic dysfunction in autism. The role of LMX1B in the development and maintenance of serotoninergic neurons is well known. In order to examine the role, if any, of LMX1B with autism pathophysiology, a trio-based SNP association study using 252 family samples from the AGRE was performed. Using pair-wise tagging method, 24 SNPs were selected from the HapMap data, based on their location and minor allele frequency. Two SNPs (rs10732392 and rs12336217) showed moderate association with autism with p values 0.018 and 0.022 respectively in transmission disequilibrium test. The haplotype AGCGTG also showed significant association (p = 0.008). Further, LMX1B mRNA expressions were studied in the postmortem brain tissues of autism subjects and healthy controls samples. LMX1B transcripts was found to be significantly lower in the anterior cingulate gyrus region of autism patients compared with controls (p = 0.049). Our study suggests a possible role of LMX1B in the pathophysiology of autism. Based on previous reports, it is likely to be mediated through a seretoninergic mechanism. This is the first report on the association of LMX1B with autism, though it should be viewed with some caution considering the modest associations we report
CO I Barcoding Reveals New Clades and Radiation Patterns of Indo-Pacific Sponges of the Family Irciniidae (Demospongiae: Dictyoceratida)
DNA barcoding is a promising tool to facilitate a rapid and unambiguous identification of sponge species. Demosponges of the order Dictyoceratida are particularly challenging to identify, but are of ecological as well as biochemical importance.Here we apply DNA barcoding with the standard CO1-barcoding marker on selected Indo-Pacific specimens of two genera, Ircinia and Psammocinia of the family Irciniidae. We show that the CO1 marker identifies several species new to science, reveals separate radiation patterns of deep-sea Ircinia sponges and indicates dispersal patterns of Psammocinia species. However, some species cannot be unambiguously barcoded by solely this marker due to low evolutionary rates.We support previous suggestions for a combination of the standard CO1 fragment with an additional fragment for sponge DNA barcoding
Dose finding of melatonin for chronic idiopathic childhood sleep onset insomnia: an RCT
Contains fulltext :
86695.pdf (publisher's version ) (Open Access)Rationale Pharmacokinetics of melatonin in children might differ from that in adults.
Objectives This study aims to establish a dose–response relationship for melatonin in advancing dim light melatonin onset (DLMO), sleep onset (SO), and reducing sleep onset latency (SOL) in children between 6 and 12 years with chronic sleep onset insomnia (CSOI).
Methods The method used for this study is the randomized, placebo-controlled double-blind trial. Children with CSOI (n=72) received either melatonin 0.05, 0.1, and 0.15 mg/kg or placebo during 1 week. Sleep was assessed with log and actigraphy during this week and the week before. Outcomes were the shifts in DLMO, SO, and SOL.
Results Treatment with melatonin significantly advanced SO and DLMO by approximately 1 h and decreased SOL by 35 min. Within the three melatonin groups, effect size was not different, but the circadian time of administration (TOA) correlated significantly with treatment effect on DLMO (rs=-0.33, p=0.022) and SO (rs=-0.38, p=0.004), whereas clock TOA was correlated with SO shift (r=-0.35, p=0.006) and not with DLMO shift.
Conclusions No dose–response relationship of melatonin with SO, SOL, and DLMO is found within a dosage range of 0.05–0.15 mg/kg. The effect of exogenous melatonin on SO, SOL, and DLMO increases with an earlier circadian TOA. The soporific effects of melatonin enhance the SO shift. This study demonstrates that melatonin for treatment of CSOI in children is effective in a dosage of 0.05 mg/kg given at least 1 to 2 h before DLMO and before desired bedtime.13 p
Phencyclidine (PCP)-Induced Disruption in Cognitive Performance is Gender-Specific and Associated with a Reduction in Brain-Derived Neurotrophic Factor (BDNF) in Specific Regions of the Female Rat Brain
Phencyclidine (PCP), used to mimic certain aspects of schizophrenia, induces sexually dimorphic, cognitive deficits in rats. In this study, the effects of sub-chronic PCP on expression of brain-derived neurotrophic factor (BDNF), a neurotrophic factor implicated in the pathogenesis of schizophrenia, have been evaluated in male and female rats. Male and female hooded-Lister rats received vehicle or PCP (n = 8 per group; 2 mg/kg i.p. twice daily for 7 days) and were tested in the attentional set shifting task prior to being sacrificed (6 weeks post-treatment). Levels of BDNF mRNA were measured in specific brain regions using in situ hybridisation. Male rats were less sensitive to PCP-induced deficits in the extra-dimensional shift stage of the attentional set shifting task compared to female rats. Quantitative analysis of brain regions demonstrated reduced BDNF levels in the medial prefrontal cortex (p < 0.05), motor cortex (p < 0.01), orbital cortex (p < 0.01), olfactory bulb (p < 0.05), retrosplenial cortex (p < 0.001), frontal cortex (p < 0.01), parietal cortex (p < 0.01), CA1 (p < 0.05) and polymorphic layer of dentate gyrus (p < 0.05) of the hippocampus and the central (p < 0.01), lateral (p < 0.05) and basolateral (p < 0.05) regions of the amygdaloid nucleus in female PCP-treated rats compared with controls. In contrast, BDNF was significantly reduced only in the orbital cortex and central amygdaloid region of male rats (p < 0.05). Results suggest that blockade of NMDA receptors by sub-chronic PCP administration has a long-lasting down-regulatory effect on BDNF mRNA expression in the female rat brain which may underlie some of the behavioural deficits observed post PCP administration
Changes in grassland management and linear infrastructures associated to the decline of an endangered bird population
European grassland birds are experiencing major population declines, mainly due to changes in
farmland management. We analyzed the role of habitat availability, grazing management and
linear infrastructures (roads and power lines) in explaining spatial and temporal variation in the
population density of little bustards (Tetrax tetrax) in Portugal, during a decade in which the species
population size halved. We used data from 51 areas (totaling ca. 1,50,000 ha) that were sampled
in two different periods (2003–2006 and 2016). In 2003–2006, when the species occurred at high
densities, habitat availability was the only factor affecting spatial variation in bustard density. In the
2016 survey, variation in density was explained by habitat availability and livestock management,
with reduced bird numbers in areas with higher proportions of cattle. Population declines across the
study period were steeper in areas that initially held higher densities of bustards and in areas with a
higher proportion of cattle in the total stocking rate. Areas with higher densities of power lines also
registered greater density declines, probably due to avoidance behavior and to increased mortality.
Overall, our results show little bustards are currently lacking high quality grassland habitat, whose
persistence depends on extensive grazing regimes and low linear infrastructure densitiesinfo:eu-repo/semantics/publishedVersio
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