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Flexible elemental stoichiometry in Trichodesmium spp. and its ecological implications
We conducted laboratory experiments to assess the bioelemental plasticity of cultures of Trichodesmium
IMS101 under phosphorus (P)-replete, P-restricted, and light-limited conditions. The results reveal a high degree
of stoichiometric flexibility. Specifically, Trichodesmium IMS101 is capable of growth with carbon (C) : nitrogen
(N) : P ratios of Câ
ââ
屉
â : Nââ±ââ : Pâ, approximately six times higher than would be predicted by the Redfield
reference ratio (Câââ : Nââ : Pâ), thus signifying low cellular P quotas relative to C and N. Luxury consumption of
P occurs rapidly after periods of prolonged P restriction, under both light and dark conditions, resulting in
substantial increases in P quotas and reductions of C : N : P ratios (Cââ±â : Nââ±â : Pâ). Comparisons of
laboratory culture data to our field observations from the Northwest Atlantic and the North Pacific indicate that,
while natural populations of Trichodesmium exhibit persistently low P content relative to C and N
(Câââ±ââ
: N â
â±â : Pâ), the highest and lowest C : P and N : P ratios recorded in the laboratory are rarely
observed in nature. We have also performed laboratory experiments intended to simulate the energetic and
nutritional extremes that would occur as naturally migrating populations of Trichodesmium sink out of the
euphotic zone into P-rich regions of the upper disphotic zone. The duration of dark survival for this isolate is on
the order of 3â6 d, after which time cells are unable to recover from light deprivation. This finding provides
a constraint on the temporal scale of vertical migration.Individual authors are also free to post PDF copies of their work published in ASLO journals on their individual or institutional websites. It is not necessary to request permission from ASLO so long as such postings are not used for commercial purposes
Advising adolescents on the use of psychotropic medication: attitudes among medical and psychology students
There is evidence that medical students are more aware of the benefits of psychotropic treatment than are members of the general public, and that the more knowledge students acquire about psychiatry and pharmacology, the more favorable their attitudes become towards psychotropic drugs and other treatments.
Objectives: This study among students investigates the relationship between certain aspects of personality and attitudes towards advising adolescents with psychosocial problems about the use of psychotropic medication.
Methods: Two groups of healthcare students were recruited from universities in Eastern France. 41 fourth-year medical students (MS) who had completed their psychiatry course, and 76 thirdyear psychology students (PS) in the faculty of human sciences. Respondents completed a selfadministered instrument (20 brief case studies, and a personality inventory) at the end of a lecture. Participation was voluntary and unpaid.
Results: MS would recommend psychotropic drugs in 40% of the 20 cases, PS in 27%. MS who would prescribe psychotropic medication differed in personality profile from PS. MS with a tendency to experience anger and related states such as frustration, and who did not see fulfilling moral obligations as important were more likely to prescribe psychotropic drugs. Also more likely to recommend psychotropic drugs, but for different reasons, were PS who were susceptible to stress but not shy or socially anxious, who showed friendliness but little interest in others, and who lacked distance in their decision-making.
Conclusion: Health promotion is not simply a matter of educating those young people who take psychotropic drugs â health professionals must also question the criteria that inform their decisions. It is as important to investigate the attitudes of the future health professionals (advisers or prescribers) as it is to focus on consumer-related issues
Genetic Variants in Inflammation-Related Genes Are Associated with Radiation-Induced Toxicity Following Treatment for Non-Small Cell Lung Cancer
Treatment of non-small cell lung cancer (NSCLC) with radiotherapy or chemoradiotherapy is often accompanied by the development of esophagitis and pneumonitis. Identifying patients who might be at increased risk for normal tissue toxicity would help in determination of the optimal radiation dose to avoid these events. We profiled 59 single nucleotide polymorphisms (SNPs) from 37 inflammation-related genes in 173 NSCLC patients with stage IIIA/IIIB (dry) disease who were treated with definitive radiation or chemoradiation. For esophagitis risk, nine SNPs were associated with a 1.5- to 4-fold increase in risk, including three PTGS2 (COX2) variants: rs20417 (HR:1.93, 95% CI:1.10â3.39), rs5275 (HR:1.58, 95% CI:1.09â2.27), and rs689470 (HR:3.38, 95% CI:1.09â10.49). Significantly increased risk of pneumonitis was observed for patients with genetic variation in the proinflammatory genes IL1A, IL8, TNF, TNFRSF1B, and MIF. In contrast, NOS3:rs1799983 displayed a protective effect with a 45% reduction in pneumonitis risk (HR:0.55, 95% CI:0.31â0.96). Pneumonitis risk was also modulated by polymorphisms in anti-inflammatory genes, including genetic variation in IL13. rs20541 and rs180925 each resulted in increased risk (HR:2.95, 95% CI:1.14â7.63 and HR:3.23, 95% CI:1.03â10.18, respectively). The cumulative effect of these SNPs on risk was dose-dependent, as evidenced by a significantly increased risk of either toxicity with an increasing number of risk genotypes (P<0.001). These results suggest that genetic variations among inflammation pathway genes may modulate the development of radiation-induced toxicity and, ultimately, help in identifying patients who are at an increased likelihood for such events
Polymorphisms in Nucleotide Excision Repair Genes, Arsenic Exposure, and Non-Melanoma Skin Cancer in New Hampshire
Background: Arsenic exposure may alter the efficiency of DNA repair. UV damage is specifically repaired by nucleotide excision repair (NER), and common genetic variants in NER may increase risk for non-melanoma skin cancer (NMSC). Objective: We tested whether polymorphisms in the NER genes XPA (A23G) and XPD (Asp312Asn and Lys751Gln) modify the association between arsenic and NMSC. Methods: Incident cases of basal and squamous cell carcinoma (BCC and SCC, respectively) were identified through a network of dermatologists and pathology laboratories across New Hampshire. Population-based controls were frequency matched to cases on age and sex. Arsenic exposure was assessed in toenail clippings. The analysis included 880 cases of BCC, 666 cases of SCC, and 780 controls. Results: There was an increased BCC risk associated with high arsenic exposure among those homozygous variant for XPA [odds ratio (OR) = 1.8; 95% confidence interval (CI), 0.9â3.7]. For XPD, having variation at both loci (312Asn and 751Gln) occurred less frequently among BCC and SCC cases compared with controls (OR = 0.8; 95% CI, 0.6â1.0) for both case groups. In the stratum of subjects who have variant for both XPD polymorphisms, there was a 2-fold increased risk of SCC associated with elevated arsenic (OR = 2.2; 95% CI, 1.0â5.0). The test for interaction between XPD and arsenic in SCC was of borderline significance (p < 0.07, 3 degrees of freedom). Conclusions: Our findings indicate a reduced NMSC risk in relation to XPD Asp312Asn and Lys751Gln variants. Further, these data support the hypothesis that NER polymorphisms may modify the association between NMSC and arsenic
Focused Analysis of Exome Sequencing Data for Rare Germline Mutations in Familial and Sporadic Lung Cancer
AbstractIntroductionThe association between smoking-induced chronic obstructive pulmonary disease (COPD) and lung cancer (LC) is well documented. Recent genome-wide association studies (GWAS) have identified 28 susceptibility loci for LC, 10 for COPD, 32 for smoking behavior, and 63 for pulmonary function, totaling 107 nonoverlapping loci. Given that common variants have been found to be associated with LC in genome-wide association studies, exome sequencing of these high-priority regions has great potential to identify novel rare causal variants.MethodsTo search for disease-causing rare germline mutations, we used a variation of the extreme phenotype approach to select 48 patients with sporadic LC who reported histories of heavy smokingâ37 of whom also exhibited carefully documented severe COPD (in whom smoking is considered the overwhelming determinant)âand 54 unique familial LC cases from families with at least three first-degree relatives with LC (who are likely enriched for genomic effects).ResultsBy focusing on exome profiles of the 107 target loci, we identified two key rare mutations. A heterozygous p.Arg696Cys variant in the coiled-coil domain containing 147 (CCDC147) gene at 10q25.1 was identified in one sporadic and two familial cases. The minor allele frequency (MAF) of this variant in the 1000 Genomes database is 0.0026. The p.Val26Met variant in the dopamine ÎČ-hydroxylase (DBH) gene at 9q34.2 was identified in two sporadic cases; the minor allele frequency of this mutation is 0.0034 according to the 1000 Genomes database. We also observed three suggestive rare mutations on 15q25.1: iron-responsive element binding protein neuronal 2 (IREB2); cholinergic receptor, nicotinic, alpha 5 (neuronal) (CHRNA5); and cholinergic receptor, nicotinic, beta 4 (CHRNB4).ConclusionsOur results demonstrated highly disruptive risk-conferring CCDC147 and DBH mutations
What characteristics of primary care and patients are associated with early death in patients with lung cancer in the UK?
Background: The UK has poor lung cancer survival rates and high early mortality, compared to other countries. We aimed to identify factors associated with early death, and features of primary care that might contribute to late diagnosis.
Methods: All cases of lung cancer diagnosed between 2000 and 2013 were extracted from The Health Improvement Network database. Patients who died within 90â
days of diagnosis were compared with those who survived longer. Standardised chest X-ray (CXR) and lung cancer rates were calculated for each practice.
Results: Of 20â142 people with lung cancer, those who died early consulted with primary care more frequently prediagnosis. Individual factors associated with early death were male sex (OR 1.17; 95% CI 1.10 to 1.24), current smoking (OR 1.43; 95% CI 1.28 to 1.61), increasing age (OR 1.80; 95% CI 1.62 to 1.99 for age â„80â
years compared to 65â69â
years), social deprivation (OR 1.16; 95% CI 1.04 to 1.30 for Townsend quintile 5 vs 1) and rural versus urban residence (OR 1.22; 95% CI 1.06 to 1.41). CXR rates varied widely, and the odds of early death were highest in the practices which requested more CXRs. Lung cancer incidence at practice level did not affect early deaths.
Conclusions: Patients who die early from lung cancer are interacting with primary care prediagnosis, suggesting potentially missed opportunities to identify them earlier. A general increase in CXR requests may not improve survival; rather, a more timely and appropriate targeting of this investigation using risk assessment tools needs further assessment
LSST Science Book, Version 2.0
A survey that can cover the sky in optical bands over wide fields to faint
magnitudes with a fast cadence will enable many of the exciting science
opportunities of the next decade. The Large Synoptic Survey Telescope (LSST)
will have an effective aperture of 6.7 meters and an imaging camera with field
of view of 9.6 deg^2, and will be devoted to a ten-year imaging survey over
20,000 deg^2 south of +15 deg. Each pointing will be imaged 2000 times with
fifteen second exposures in six broad bands from 0.35 to 1.1 microns, to a
total point-source depth of r~27.5. The LSST Science Book describes the basic
parameters of the LSST hardware, software, and observing plans. The book
discusses educational and outreach opportunities, then goes on to describe a
broad range of science that LSST will revolutionize: mapping the inner and
outer Solar System, stellar populations in the Milky Way and nearby galaxies,
the structure of the Milky Way disk and halo and other objects in the Local
Volume, transient and variable objects both at low and high redshift, and the
properties of normal and active galaxies at low and high redshift. It then
turns to far-field cosmological topics, exploring properties of supernovae to
z~1, strong and weak lensing, the large-scale distribution of galaxies and
baryon oscillations, and how these different probes may be combined to
constrain cosmological models and the physics of dark energy.Comment: 596 pages. Also available at full resolution at
http://www.lsst.org/lsst/sciboo
Conception participative et Ă©valuation d'un serious game pour les enfants asthmatiques
International audienceThe study described in this paper highlighted the participatory design process (PD) in the context of asthma e-learning. First, we described global process to design this tool named KidBreath. Second, we evaluated in two Year 4 classes its efficacy in a motivation way, usability, disease knowledge and interests of children by their system. Results showed, in acceptance with behaviors, high level of intrinsic motivation when using KidBreath, usability and enjoyment of edutainment activities. This pilot study tends to confirm to continue with this approach with asthma kids at home.L'Ă©tude dĂ©crite dans cet article met en exergue l'intĂ©rĂȘt d'une approche de conception participative (CP) dans le cadre d'un apprentissage en ligne sur l'asthme pour les enfants. AprĂšs avoir dĂ©crit l'ensemble de la dĂ©marche pour la conception de cet e-learning nommĂ© KidBreath, nous Ă©valuons dans 2 classes de CE2 son efficacitĂ© au niveau motivationnel, utilisabilitĂ©, connaissance sur la maladie et Ă©mergence de l'intĂ©rĂȘt que les enfants y portent Ă travers la curiositĂ© qui en Ă©merge. Les rĂ©sultats, probants aux comportements observĂ©s, montrent un haut niveau de motivation intrinsĂšque pour utiliser l'outil, un fort taux d'utilisabilitĂ© et une grande satisfaction des activitĂ©s ludo-Ă©ducatives. Cette Ă©tude pilote nous confirme de continuer dans cette approche en testant le systĂšme notamment auprĂšs des enfants asthmatiques sur du moyen terme
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