658 research outputs found
Rotation of Coulomb crystals in a magnetized inductively coupled complex plasma
Under suitable conditions, micron-sized dust particles introduced into inductively coupled argon plasma form a stable microscopic crystal lattice, known as a Coulomb (or plasma) crystal. In the experiment described, an external axial magnetic field was applied to various configurations of Coulomb crystal, including small crystal lattices consisting of one to several particles, and large crystal lattices with many hundreds of particles. The crystals were observed to rotate collectively under the influence of the magnetic field. This paper describes the experimental procedures and the preliminary results of this investigation
Conservation practice could benefit from routine testing and publication of management outcomes
Effective conservation requires a step change in the way practitioners can contribute to science and
can have access to research outputs. The journal Conservation Evidence was established in 2004 to
help practitioners surmount several obstacles they face when attempting to document the effects of
their conservation actions scientifically. It is easily and freely accessible online. It is free to publish in
and it enables global communication of the effects of practical trials and experiments, which are
virtually impossible to get published in most scientific journals. The driving force behind
Conservation Evidence is the need to generate and share scientific information about the effects of
interventions
The Frequency of Ras Mutations in Cancer
Ras is frequently mutated in cancer, however, there is a lack of consensus in the literature regarding the cancer mutation frequency of Ras, with quoted values varying from 10%â30%. This variability is at least in part due to the selective aggregation of data from different databases and the dominant influence of particular cancer types and particular Ras isoforms within these datasets. To provide a more definitive figure for Ras mutation frequency in cancer, we cross-referenced the data in all major publicly accessible cancer mutation databases to determine reliable mutation frequency values for each Ras isoform in all major cancer types. These percentages were then applied to current U.S. cancer incidence statistics to estimate the number of new patients each year that have Ras-mutant cancers. We find that approximately 19% of patients with cancer harbor Ras mutations, equivalent to approximately 3.4 million new cases per year worldwide. We discuss the Ras isoform and mutation-specific trends evident within the datasets that are relevant to current Ras-targeted therapies
Mortality in Patients With Gout Treated With Allopurinol: A Systematic Review and MetaâAnalysis
ObjectiveUrateâlowering therapy (predominantly allopurinol) is highly effective as a treatment for gout, but its wider longâterm effects remain unclear. This systematic review and metaâanalysis aimed to ascertain the association between mortality and the use of allopurinol in patients with gout.MethodMedline, Embase, CINAHL, and the Cochrane Library were searched from inception to August 2018. Articles eligible for inclusion used a cohort design and examined cardiovascular or allâcause mortality in patients diagnosed with gout and prescribed allopurinol. Information on study characteristics, design, sample size, and mortality risk estimates were extracted. Article quality was assessed using the NewcastleâOttawa Scale. Included articles were described in a narrative synthesis and, where possible, risk estimate data were pooled.ResultsFour articles reported a hazard ratio (HR) risk estimate for allâcause mortality in patients with gout using allopurinol, and 2 of these also reported cardiovascular mortality. Two articles found allopurinol to be protective in patients with gout, 1 found no statistically significant association, and 1 found no statistically significant effect of escalation of allopurinol dosage on allâcause or cardiovascularârelated mortality. Data pooling was possible for allâcause mortality and found no association between allopurinol use in patients with gout and allâcause mortality compared to patients with gout not using allopurinol (adjusted HR 0.80 [95% confidence interval 0.60â1.05]).ConclusionThere was no significant association between allâcause mortality and allopurinol use in people with gout. However, the number of included studies was small, suggesting that further studies are needed
Reply to Dr. Lai regarding Allopurinol Hypersensitivity Syndrome in patients of Asian ancestry
We thank Dr Lai for their interest in our study (1). While we did not show a statistically significant link between the use of allopurinol and mortality in people with gout, we agree that Allopurinol Hypersensitivity Syndrome (AHS) is the most serious side-effect of allopurinol, particularly in populations with South East Asian ancestry, leading to the recommendation to screen people of South East Asian descent for the HLA-B*5801 allele prior to starting treatment with allopurinol (2,3)
Manganese-enhanced magnetic resonance imaging depicts brain activity in models of acute and chronic pain: a new window to study experimental spontaneous pain?
Application of functional imaging techniques to animal models is vital to understand pain mechanisms, but is often confounded by the need to limit movement artefacts with anaesthesia, and a focus on evoked responses rather than clinically relevant spontaneous pain and related hyperalgesia. The aim of the present study was to investigate the potential of manganese-enhanced magnetic resonance imaging (MEMRI) to measure neural responses during on-going pain that underpins hyperalgesia in pre-clinical models of nociception. As a proof of concept that MEMRI is sensitive to the neural activity of spontaneous, intermittent behaviour, we studied a separate positive control group undergoing a voluntary running wheel experiment.
In the pain models, pain behaviour (weight bearing asymmetry and hindpaw withdrawal thresholds (PWTs)) was measured at baseline and following either intra-articular injection of nerve growth factor (NGF, 10 ”g/50 ”l; acute pain model, n=4 rats per group), or the chondrocyte toxin monosodium iodoacetate (MIA, 1 mg/50 ”l; chronic model, n=8 rats per group), or control injection. Separate groups of rats underwent a voluntary wheel running protocol (n=8 rats per group). Rats were administered with paramagnetic ion Mn2+ as soluble MnCl2 over seven days (subcutaneous osmotic pump) to allow cumulative activity-dependent neural accumulation in the models of pain, or over a period of running. T1-weighted MR imaging at 7 T was performed under isoflurane anaesthesia using a receive-only rat head coil in combination with a 72 mm volume coil for excitation.
The pain models resulted in weight bearing asymmetry (NGF: 20.0 ± 5.2%, MIA: 15 ± 3%), and a reduction in PWT in the MIA model (8.3 ± 1.5 g) on the final day of assessment before undergoing MR imaging. Voxel-wise and region-based analysis of MEMRI data did not identify group differences in T1 signal. However, MnCl2 accumulation in the VTA, right Ce amygdala, and left cingulate was negatively correlated with pain responses (greater differences in weight bearing), similarly MnCl2 accumulation was reduced in the VTA in line with hyperalgesia (lower PWTs), which suggests reduced regional activation as a result of the intensity and duration of pain experienced during the 7 days of MnCl2 exposure. Motor cortex T1-weighted signal increase was associated with the distance ran in the wheel running study, while no between group difference was seen. Our data suggest that on-going pain related signal changes identified using MEMRI offers a new window to study the neural underpinnings of spontaneous pain in rats
Influence of C02 enrichment and nitrogen fertilization on tissue chemistry and carbon allocation in longleaf pine seedlings
One-year old, nursery-grown longleaf pine (Pinus palustris Mill.) seedlings were grown in 45-L pots containing a
coarse sandy medium and were exposed to two concentrations of atmospheric CO2 (365 or 720 ”mol?1) and two
levels of nitrogen (N) fertility (40 or 400 kg N ha?1 yr?1) within open top chambers for 20 months. At harvest,
needles, stems, coarse roots, and fine roots were separated and weighed. Subsamples of each tissue were frozen
in liquid N, lyophilized at ?50 ?C, and ground to pass a 0.2 mm sieve. Tissue samples were analyzed for carbon
(C), N, nonpolar extractives (fats, waxes, and oils = FWO), nonstructural carbohydrates (total sugars and starch),
and structural carbohydrates (cellulose, lignin, and tannins). Increased dry weights of each tissue were observed
under elevated CO2 and with high N; however, main effects of CO2 were significant only on belowground tissues.
The high N fertility tended to result in increased partitioning of biomass aboveground, resulting in significantly
lower root to shoot ratios. Elevated CO2 did not affect biomass allocation among tissues. Both atmospheric CO2
and N fertility tended to affect concentration of C compounds in belowground, more than aboveground, tissues.
Elevated CO2 resulted in lower concentrations of starch, cellulose, and lignin, but increased concentrations of
FWO in root tissues. High N fertility increased the concentration of starch, cellulose, and tannins, but resulted in
lower concentrations of lignin and FWO in roots. Differences between CO2 concentrations tended to occur only
with high N fertility. Atmospheric CO2 did not affect allocation patterns for any compound; however the high N
treatment tended to result in a lower percentage of sugars, cellulose, and lignin belowgroun
Proteomic Analysis of GLUT4 Storage Vesicles Reveals Tumor Suppressor Candidate 5 (TUSC5) as a Novel Regulator of Insulin Action in Adipocytes.
Insulin signaling augments glucose transport by regulating glucose transporter 4 (GLUT4) trafficking from specialized intracellular compartments, termed GLUT4 storage vesicles (GSVs), to the plasma membrane. Proteomic analysis of GSVs by mass spectrometry revealed enrichment of 59 proteins in these vesicles. We measured reduced abundance of 23 of these proteins following insulin stimulation and assigned these as high confidence GSV proteins. These included established GSV proteins such as GLUT4 and insulin-responsive aminopeptidase, as well as six proteins not previously reported to be localized to GSVs. Tumor suppressor candidate 5 (TUSC5) was shown to be a novel GSV protein that underwent a 3.7-fold increase in abundance at the plasma membrane in response to insulin. siRNA-mediated knockdown of TUSC5 decreased insulin-stimulated glucose uptake, although overexpression of TUSC5 had the opposite effect, implicating TUSC5 as a positive regulator of insulin-stimulated glucose transport in adipocytes. Incubation of adipocytes with TNFα caused insulin resistance and a concomitant reduction in TUSC5. Consistent with previous studies, peroxisome proliferator-activated receptor (PPAR) γ agonism reversed TNFα-induced insulin resistance. TUSC5 expression was necessary but insufficient for PPARγ-mediated reversal of insulin resistance. These findings functionally link TUSC5 to GLUT4 trafficking, insulin action, insulin resistance, and PPARγ action in the adipocyte. Further studies are required to establish the exact role of TUSC5 in adipocytes
Gender-specific risk factors for gout: a systematic review of cohort studies
BACKGROUND:Though gout is more prevalent in men than women, it remains unclear whether gender influences risk factors for incident gout. We aimed to systematically review all cohort studies examining risk factors for the development of gout by gender.METHODS: MEDLINE, EMBASE, CINAHL and the Cochrane Library were searched from inception to March 2019. Risk factors for gout examined were: age, ethnicity, consumption of alcohol, meat, seafood, dairy products, purine-rich vegetables, coffee and fructose, vitamin C intake, the Dietary Approaches to Stop Hypertension (DASH) diet, metabolic syndrome, BMI, waist and chest circumference, waist-to-hip ratio, weight change, diabetes mellitus, dyslipidaemias, renal disease, psoriasis, hypertension, diuretic use and anti-diabetic medication. Cohort studies were included if examining (at least) one of these risk factors for gout in either gender in the general population or primary care. Sample characteristics from included articles and their reported risk estimates were described using narrative synthesis.RESULTS:Thirty-three articles were included, 20 (60.6%)directly compared risk factors by gender, 10 (30.3%) used men-only samples, 3 (9.1%) used women-only samples. Articles comparing risk across genders found similar increases in most risk factors. However, in men, metabolic syndrome (Hazard Ratio (95% CI) 1.37(1.20-1.58)) presented a risk of incident gout compared to none in women (>?50?years 1.15(0.85-1.54); =50?years 1.29(0.76-2.17)). Compared to men, women showed greater associated risk with higher consumption of fish and shellfish (HR (95% CI) Men: 1.02 (0.86-1.22); Women 1.36 (1.12-1.65)).CONCLUSIONS:Risk factors for developing gout did not typically differ between genders and therefore similar preventative advice can be provided. Exceptions were metabolic syndrome in men and excessive seafood consumption in women, but these singular articles need further examination and in general more research into the risk factors for gout which includes women is required
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