ABSTRACT
We investigate the link between the bar rotation rate and dark matter content in barred galaxies by concentrating on the cases of the lenticular galaxies NGC 4264 and NGC 4277. These two ...gas-poor galaxies have similar morphologies, sizes, and luminosities. But, NGC 4264 hosts a fast bar, which extends to nearly the corotation, while the bar embedded in NGC 4277 is slow and falls short of corotation. We derive the fraction of dark matter fDM, bar within the bar region from Jeans axisymmetric dynamical models by matching the stellar kinematics obtained with the MUSE integral-field spectrograph and using SDSS images to recover the stellar mass distribution. We build mass-follows-light models as well as mass models with a spherical halo of dark matter, which is not tied to the stars. We find that the inner regions of NGC 4277 host a larger fraction of dark matter ($f_{\rm DM, bar}\, =\, 0.53\pm 0.02$) with respect to NGC 4264 ($f_{\rm DM, bar}\, =\, 0.33\pm 0.04$) in agreement with the predictions of theoretical works and the findings of numerical simulations, which have found that fast bars live in baryon-dominated discs, whereas slow bars experienced a strong drag from the dynamical friction due to a dense DM halo. This is the first time that the bar rotation rate is coupled to fDM, bar derived from dynamical modelling.
It has been reported that EGFR mutations in lung carcinomas make the disease more responsive to treatment with tyrosine kinase inhibitors. We decided to evaluate the prevalence of EGFR mutations in a ...large series of non-small-cell lung carcinomas (NSCLCs) and to develop a rapid and sensitive screening method. PATIENTS AND METHODS We examined 860 consecutive NSCLC patients for EGFR mutations in exons 18, 19, and 21 using a dual technical approach--direct sequencing of polymerase chain reaction (PCR) products and PCR single-strand conformation polymorphism (SSCP) analysis. Moreover, all lung adenocarcinomas were analyzed for K-ras mutations at codon 12 by allele-specific oligoprobe hybriditations.
There were no EGFR mutations in 454 squamous carcinomas and 31 large cell carcinomas investigated. Thirty-nine mutations were found in the series of 375 adenocarcinomas (10%). Mutations were present in 26% of 86 bronchioloalveolar carcinomas (BACs) and in 6% of 289 conventional lung adenocarcinomas; P = .000002. EGFR mutations and K-ras mutations were mutually exclusive. A multivariable analysis revealed that BAC histotype, being a never smoker, and female sex were independently associated with EGFR mutations (odds ratios: 4.542, 3.632, and 2.895, respectively). The SSCP analysis was accurate and sensitive, allowing identification of mutations that were undetectable (21% of cases) by direct sequencing.
Mutations in the EGFR tyrosine kinase domain define a new molecular type of lung carcinoma, more frequent in particular subsets of patients. The SSCP assay is a rapid and reliable method for the detection of EGFR kinase domain mutations in lung cancer.
Aims.
We characterised the properties of the bar hosted in lenticular galaxy NGC 4277, which is located behind the Virgo cluster.
Methods.
We measured the bar length and strength from the surface ...photometry obtained from the broad-band imaging of the Sloan Digital Sky Survey and we derived the bar pattern speed from the stellar kinematics obtained from the integral-field spectroscopy performed with the Multi Unit Spectroscopic Explorer at the Very Large Telescope. We also estimated the co-rotation radius from the circular velocity, which we constrained by correcting the stellar streaming motions for asymmetric drift, and we finally derived the bar rotation rate.
Results.
We found that NGC 4277 hosts a short (
R
bar
= 3.2
−0.6
+0.9
kpc), weak (
S
bar
= 0.21 ± 0.02), and slow (ℛ = 1.8
−0.3
+0.5
) bar and its pattern speed (Ω
bar
= 24.7 ± 3.4 km s
−1
kpc
−1
) is amongst the best-constrained ones ever obtained with the Tremaine–Weinberg (TW) method with relative statistical errors of ∼0.2.
Conclusions.
NGC 4277 is the first clear-cut case of a galaxy hosting a slow stellar bar (ℛ > 1.4 at more than a 1
σ
confidence level) measured with the model-independent TW method. A possible interaction with the neighbour galaxy NGC 4273 could have triggered the formation of such a slow bar and/or the bar could be slowed down due to the dynamical friction with a significant amount of dark matter within the bar region.
ABSTRACT
Dwarf barred galaxies are the perfect candidates for hosting slowly rotating bars. They are common in dense environments and have a relatively shallow potential well, making them prone to ...heating by interactions. When an interaction induces bar formation, the bar should rotate slowly. They reside in massive and centrally concentrated dark matter haloes, which slow down the bar rotation through dynamical friction. While predictions suggest that slow bars should be common, measurements of bar pattern speed, using the Tremaine–Weinberg method, show that bars are mostly fast in the local Universe. We present a photometric and kinematic characterization of bars hosted by two dwarf galaxies in the Virgo Cluster, NGC 4483, and NGC 4516. We derive the bar length and strength using the Next Generation Virgo Survey imaging and the circular velocity, bar pattern speed, and rotation rate using spectroscopy from the Multi-Unit Spectroscopic Explorer. Including the previously studied galaxy IC 3167, we compare the bar properties of the three dwarf galaxies with those of their massive counterparts from literature. Bars in the dwarf galaxies are shorter and weaker, and rotate slightly slower with respect to those in massive galaxies. This could be due to a different bar formation mechanism and/or to a large dark matter fraction in the centre of dwarf galaxies. We show that it is possible to push the application of the Tremaine–Weinberg method to the galaxy low-mass regime.
Several small molecules, epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs), such as gefitinib, erlotinib and afatinib, have been demonstrated to significantly improve clinical ...outcomes in patients with advanced EGFR-mutated non-small cell lung cancer (NSCLC), but erlotinib activity in EGFR wild-type squamous carcinoma is still highly debated. Here, we describe a prolonged and unexpected clinical response to erlotinib in a male former heavy cigarette smoker with wild-type EGFR squamous-cell cancer.
p21 protein (p21) inhibitor of cyclin-dependent kinases is a critical downstream effector in the p53-specific pathway of growth control and can also be induced by p53-independent pathways in relation ...to terminal differentiation. We investigated p21 immunoreactivity in 261 breast carcinomas (141 node negative and 120 node positive) with long-term follow-up (median, 73 months; range, 37-119). p21 was seen in 214 (82%) infiltrating tumors, staining was nuclear and heterogeneous, and the p21 labeling index ranged from 0 to 90%. Sixty-eight (32%) patients showed p21 overexpression (>10% of reactive tumor cells). p21 overexpression was associated with large tumor size, positive nodal status, high histological grade, and high mitotic count and was related to short disease-free survival (DFS) in the whole series of patients (P = 0.04), in the node-negative subgroup (P = 0.004), and in the group of patients who did not undergo systemic adjuvant therapy (P = 0.003). In patients treated with systemic adjuvant therapy, bivariate analysis of the combined p21 and p53 phenotypes showed that p21+/p53+ tumors were associated with long DFS and overall survival (OS), whereas p21-/p53+ tumors had the worst prognosis. In treated patients, multivariate analysis showed that the p21-/53+ phenotype was independently associated with short DFS and OS. Our present data support the hypothesis that p21/p53 heterogeneous expression may be of clinical relevance for the therapeutic response to chemotherapy/hormonotherapy. The p21-/p53+ phenotype could correspond to a situation where p53 overexpression really reflects complete abrogation of p53 function. These cases with disrupted p53 function should have impaired the G1 checkpoint and may not be able to activate the apoptotic cascade in response to DNA-damaging drugs.
Cette étude a pour objectif d’explorer les liens entre l’anxiété sociale et la satisfaction des besoins d’autonomie, de compétence et d’affiliation sociale chez les adolescents obèses. Pour la ...Théorie de l’autodétermination, l’insatisfaction de ces trois besoins psychologiques fondamentaux serait associée à la présence de psychopathologies. L’anxiété sociale est le trouble anxieux le plus fréquent chez les adolescents obèses, mais ses liens avec la satisfaction des besoins n’ont pas encore été étudiés dans cette population.
Dix-sept adolescents obèses issus d’une population clinique et 67 adolescents normopondéraux issus de la population générale ont complété l’Échelle de peur des jugements négatifs d’autrui (PJNA), l’Échelle de perception de compétence dans les domaines de vie (EPCDV), l’Échelle de perception d’autonomie dans les domaines de vie (EPADV) et l’Échelle de la qualité des relations interpersonnelles (EQRI).
Comparativement aux adolescents normopondéraux, les adolescents obèses présentent une moins bonne satisfaction des besoins de compétence et d’autonomie dans les loisirs. L’anxiété sociale est corrélée à l’insatisfaction des besoins d’autonomie et de compétence dans le domaine des relations interpersonnelles, de compétence générale et d’appartenance sociale vis-à-vis des amis.
Les difficultés éprouvées par les adolescents obèses dans les activités physiques pourraient expliquer l’insatisfaction des besoins d’autonomie et de compétence dans les loisirs. La prise en charge des adolescents obèses pourrait intégrer des interventions centrées sur l’amélioration de la satisfaction de ces besoins, ainsi que sur les besoins associés à l’anxiété sociale afin d’en prévenir le développement dans cette population.
The objective of this study is to evaluate the relationship between social anxiety and satisfaction of needs for autonomy, competence and relatedness in obese adolescents. Literature review reports that obese children and adolescents have higher social anxiety that their normal weight peers. But relations between obesity and social anxiety are not clear. We explore the relationship between social anxiety and satisfaction of needs for autonomy, competence and relatedness, three basic psychological needs advanced by Self-Determination Theory (SDT). SDT predicts that satisfaction of these needs should result in well-being and mental health. Thereby, a low satisfaction of the needs for autonomy, competence and relatedness is associated with psychopathology. These psychological needs are not yet explored in obese adolescents. We expect that obese adolescents have higher social anxiety and lower satisfaction of the needs for autonomy, competence and relatedness as compared to controls. Furthermore, high social anxiety could be associated with low satisfaction of these needs.
The study sample consists of a clinical group of 17 obese adolescents and a control group of 67 normal weight adolescents. They completed self-report questionnaires. Social anxiety was assessed with the Fear of Negative Evaluation Scale (FNE). Satisfaction of the needs for autonomy, competence and relatedness was measured with the Perceived Autonomy in Life Domains Scale (PALDS), the Perception of Competence in Life Domains Scale (PCLDS) and the Interpersonal Relationship Quality Scale (EQRI).
Obese adolescents have significantly lower satisfaction of needs for autonomy and competence in leisure domain as compared to controls. Social anxiety is negatively correlated with satisfaction of needs for autonomy and competence in interpersonal relationships domain, general competence and relatedness with friends.
Physical complications in obese adolescents could explain dissatisfaction of needs for autonomy and competence in leisure domain. This assumption could be explored in future research. Results should improve treatment of obese adolescents. Consistent with SDT, satisfaction of the needs for autonomy, competence and relatedness is linked with social anxiety. Impairment of satisfaction of these needs could contribute to understanding the social anxiety in adolescents.
We investigate the link between the bar rotation rate and dark matter content in barred galaxies by concentrating on the cases of the lenticular galaxies NGC4264 and NGC4277. These two gas-poor ...galaxies have similar morphologies, sizes, and luminosities. But, NGC4264 hosts a fast bar, which extends to nearly the corotation, while the bar embedded in NGC4277 is slow and falls short of corotation. We derive the fraction of dark matter \(f_{\rm DM, bar}\) within the bar region from Jeans axisymmetric dynamical models by matching the stellar kinematics obtained with the MUSE integral-field spectrograph and using SDSS images to recover the stellar mass distribution. We build mass-follows-light models as well as mass models with a spherical halo of dark matter, which is not tied to the stars. We find that the inner regions of NGC4277 host a larger fraction of dark matter (\(f_{\rm DM, bar} = 0.53 \pm 0.02\)) with respect to NGC4264 (\(f_{\rm DM, bar} = 0.33 \pm 0.04\)) in agreement with the predictions of theoretical works and the findings of numerical simulations, which have found that fast bars live in baryon-dominated discs, whereas slow bars experienced a strong drag from the dynamical friction due to a dense DM halo. This is the first time that the bar rotation rate is coupled to \(f_{\rm DM, bar}\) derived from dynamical modelling.
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