716 research outputs found
CT texture analysis can help differentiate between malignant and benign lymph nodes in the mediastinum in patients suspected for lung cancer
BACKGROUND: In patients with non-small-cell lung carcinoma NSCLC the lymph node staging in the mediastinum is important due to impact on management and prognosis. Computed tomography texture analysis (CTTA) is a postprocessing technique that can evaluate the heterogeneity of marked regions in images. PURPOSE: To evaluate if CTTA can differentiate between malignant and benign lymph nodes in a cohort of patients with suspected lung cancer. MATERIAL AND METHODS: With tissue sampling as reference standard, 46 lymph nodes from 29 patients were analyzed using CTTA. For each lymph node, CTTA was performed using a research software "TexRAD" by drawing a region of interest (ROI) on all available axial contrast-enhanced computed tomography (CT) slices covering the entire volume of the lymph node. Lymph node CTTA comprised image filtration-histogram analysis undertakes two stages: the first step comprised an application of a Laplacian of Gaussian filter to highlight fine to coarse textures within the ROI, followed by a quantification of textures via histogram analysis using mean gray-level intensity from the entire volume of the lymph nodes. RESULTS: CTTA demonstrated a statistically significant difference between the malignant and the benign lymph nodes (Pâ=â0.001), and by binary logistic regression we obtained a sensitivity of 53% and specificity of 97% in the test population. The area under the receiver operating curve was 83.4% and reproducibility was excellent. CONCLUSION: CTTA may be helpful in differentiating between malignant and benign lymph nodes in the mediastinum in patients suspected for lung cancer, with a low intra-observer variance
Dynamic properties of noise and Her6 levels are optimized by miR-9, allowing the decoding of the Her6 oscillator
This work was supported by a Wellcome Trust Senior Research Fellowship to NP (106185/Z/14/Z).Noise is prevalent in biology and has been widely quantified using snapshot measurements. This static view obscures our understanding of dynamic noise properties and how these affect gene expression and cell state transitions. Using a CRISPR/Cas9 Zebrafish her6::Venus reporter combined with mathematical and in vivo experimentation, we explore how noise affects the protein dynamics of Her6, a basic helixâloopâhelix transcriptional repressor. During neurogenesis, Her6 expression transitions from fluctuating to oscillatory at singleâcell level. We identify that absence of miRâ9 input generates highâfrequency noise in Her6 traces, inhibits the transition to oscillatory protein expression and prevents the downregulation of Her6. Together, these impair the upregulation of downstream targets and cells accumulate in a normally transitory state where progenitor and early differentiation markers are coâexpressed. Computational modelling and double smFISH of her6 and the early neurogenesis marker, elavl3, suggest that the change in Her6 dynamics precedes the downregulation in Her6 levels. This sheds light onto the order of events at the moment of cell state transition and how this is influenced by the dynamic properties of noise. Our results suggest that Her/Hes oscillations, facilitated by dynamic noise optimization by miRâ9, endow progenitor cells with the ability to make a cell state transition.Publisher PDFPeer reviewe
Haemoglobin mass and running time trial performance after recombinant human erythropoietin administration in trained men
<p>Recombinant human erythropoietin (rHuEpo) increases haemoglobin mass (Hbmass) and maximal oxygen uptake (vË O2 max).</p>
<p>Purpose: This study defined the time course of changes in Hbmass, vË O2 max as well as running time trial performance
following 4 weeks of rHuEpo administration to determine whether the laboratory observations would translate into actual
improvements in running performance in the field.</p>
<p>Methods: 19 trained men received rHuEpo injections of 50 IUNkg21 body mass every two days for 4 weeks. Hbmass was
determined weekly using the optimized carbon monoxide rebreathing method until 4 weeks after administration. vË O2 max
and 3,000 m time trial performance were measured pre, post administration and at the end of the study.</p>
<p>Results: Relative to baseline, running performance significantly improved by ,6% after administration (10:3061:07 min:sec
vs. 11:0861:15 min:sec, p,0.001) and remained significantly enhanced by ,3% 4 weeks after administration
(10:4661:13 min:sec, p,0.001), while vË O2 max was also significantly increased post administration
(60.765.8 mLNmin21Nkg21 vs. 56.066.2 mLNmin21Nkg21, p,0.001) and remained significantly increased 4 weeks after
rHuEpo (58.065.6 mLNmin21Nkg21, p = 0.021). Hbmass was significantly increased at the end of administration compared to
baseline (15.261.5 gNkg21 vs. 12.761.2 gNkg21, p,0.001). The rate of decrease in Hbmass toward baseline values post
rHuEpo was similar to that of the increase during administration (20.53 gNkg21Nwk21, 95% confidence interval (CI) (20.68,
20.38) vs. 0.54 gNkg21Nwk21, CI (0.46, 0.63)) but Hbmass was still significantly elevated 4 weeks after administration
compared to baseline (13.761.1 gNkg21, p<0.001).</p>
<p>Conclusion: Running performance was improved following 4 weeks of rHuEpo and remained elevated 4 weeks after
administration compared to baseline. These field performance effects coincided with rHuEpo-induced elevated vË O2 max and
Hbmass.</p>
New uses of the Migraine Screen Questionnaire (MS-Q): validation in the Primary Care setting and ability to detect hidden migraine. MS-Q in Primary Care
<p>Abstract</p> <p>Background</p> <p>PC plays an important role in early diagnosis of health disorders, particularly migraine, due to the financial impact of this disease for the society and its impact on patients' quality of life. The aim of the study was to validate the self-administered MS-Q questionnaire for detection of hidden migraine in the field of primary care (PC), and to explore its use in this setting.</p> <p>Methods</p> <p>Cross-sectional, observational, and multicentre study in subjects above 18 years of age patients attending PC centers (regardless of the reason for consultation). A MS-Q score ℠4 was considered possible migraine. Level of agreement with IHS criteria clinical diagnosis (kappa coefficient), and instrument's validity properties: sensitivity, specificity, positive (PPV) and negative (NPV) predictive values were determined. The ability of the instrument to identify possible new cases of migraine was calculated, as well as the ratio of hidden disease compared to the ratio obtained by IHS criteria.</p> <p>Results</p> <p>A total of 9,670 patients were included [48.9 ± 17.2 years (mean ± SD); 61.9% women], from 410 PC centers representative of the whole national territory. The clinical prevalence of migraine according to the IHS criteria was 24.7%, and 20.4% according to MS-Q: Kappa index of agreement 0.82 (p < 0.05). MS-Q sensitivity was 0.82 (95% CI, 0.81 - 0.84), specificity 0.97 (95% CI, 0.98 - 0.99), PPV 0.95 (95% CI, 0.94 - 0.96), and NPV 0.94 (95% CI, 0.93 - 0.95). No statistically significant differences were found in the percentages of patients with <it>de novo </it>and hidden migraine identified by MS-Q and by IHS criteria: 5.7% vs. 6.1% and 26.6% vs. 24.1%, respectively.</p> <p>Conclusions</p> <p>The results of the present study confirm the usefulness of the MS-Q questionnaire for the early detection and assessment of migraine in PC settings, and its ability to detect hidden migraine.</p
Somatostatin and dopamine receptors as targets for medical treatment of Cushing's Syndrome
Somatostatin (SS) and dopamine (DA) receptors are widely expressed in neuroendocrine tumours that cause Cushing's Syndrome (CS). Increasing knowledge of specific subtype expression within these tumours and the ability to target these receptor subtypes with high-affinity compounds, has driven the search for new SS- or DA-based medical therapies for the various forms of CS. In Cushing's disease, corticotroph adenomas mainly express dopamine receptor subtype 2 (D2) and somatostatin receptor subtype 5 (sst5), whereas sst2is expressed at lower levels. Activation of these receptors can inhibit ACTH-release in primary cultured corticotroph adenomas and compounds that target either sst5(pasireotide, or SOM230) or D2(cabergoline) have shown significant efficacy in subsets of patients in recent clinical studies. Combination therapy, either by administration of both types of compounds separately or by treatment with novel somatostatin-dopamine chimeric molecules (e.g. BIM-23A760), appears to be a promising approach in this respect. In selected cases of Ectopic ACTH-producing Syndrome (EAS), the sst2-preferring compound octreotide is able to reduce cortisol levels effectively. A recent study showed that D2receptors are also significantly expressed in the majority of EAS and that cabergoline may decrease cortisol levels in subsets of these patients. In both normal adrenal tissue as well as in adrenal adenomas and carcinomas that cause CS, sst and DA receptor expression has been demonstrated. Although selected cases of adrenal CS may benefit from sst or DA-targeted treatment, its total contribution to the treatment of these patients is likely to be low as surgery is effective in most cases
Platelet and Neutrophil Responses to Gram Positive Pathogens in Patients with Bacteremic Infection
BACKGROUND: Many Gram-positive pathogens aggregate and activate platelets in vitro and this has been proposed to contribute to virulence. Platelets can also form complexes with neutrophils but little is however known about platelet and platelet-neutrophil responses in bacterial infection. METHODOLOGY/PRINCIPAL FINDINGS: We added isolates of Gram-positive bacteria from 38 patients with a bacteremic infection to blood drawn from the same patient. Aggregometry and flow cytometry were used to assess platelet aggregation and to quantify activation of platelets, neutrophils, and platelet-neutrophils complexes (PNCs) induced by the bacteria. Fifteen healthy persons served as controls. Most isolates of Staphylococcus aureus, beta hemolytic streptococci, and Enterococcus faecalis induced aggregation of platelets from their respective hosts, whereas pneumococci failed to do so. S. aureus isolates induced platelet aggregation more rapidly in patients than in controls, whereas platelet activation by S. aureus was lower in patients than in controls. PNCs were more abundant in baseline samples from patients than in healthy controls and most bacterial isolates induced additional PNC formation and neutrophil activation. CONCLUSION/SIGNIFICANCE: We have demonstrated for the first time that bacteria isolated from patients with Gram-positive bacteremia can induce platelet activation and aggregation, PNC formation, and neutrophil activation in the same infected host. This underlines the significance of these interactions during infection, which could be a target for future therapies in sepsis
Detection of a Single Identical Cytomegalovirus (CMV) Strain in Recently Seroconverted Young Women
Infection with multiple CMV strains is common in immunocompromised hosts, but its occurrence in normal hosts has not been well-studied.We analyzed CMV strains longitudinally in women who acquired CMV while enrolled in a CMV glycoprotein B (gB) vaccine trial. Sequencing of four variable genes was performed in samples collected from seroconversion and up to 34 months thereafter.199 cultured isolates from 53 women and 65 original fluids from a subset of 19 women were sequenced. 51 women were infected with one strain each without evidence for genetic drift; only two women shed multiple strains. Genetic variability among strains increased with the number of sequenced genetic loci. Nevertheless, 13 of 53 women proved to be infected with an identical CMV strain based on sequencing at all four variable genes. CMV vaccine did not alter the degree of genetic diversity amongst strains.Primary CMV infection in healthy women nearly always involves shedding of one strain that remains stable over time. Immunization with CMVgB-1 vaccine strain is not selective against specific strains. Although 75% of women harbored their unique strain, or a strain shared with only one other woman, 25% shared a single common strain, suggesting that this predominant strain with a particular combination of genetic loci is advantageous in this large urban area
Determinants of Non-Vaccination against Pandemic 2009 H1N1 Influenza in Pregnant Women: A Prospective Cohort Study
International audienceBACKGROUND: In October 2009, the French government organized a national-wide, free of charge vaccination campaign against pandemic H1N1 influenza virus, especially targeting pregnant women, a high risk group for severe illness. The study objective was to evaluate pandemic flu vaccine uptake and factors associated with non-vaccination in a population of pregnant women. METHODOLOGY/PRINCIPAL FINDINGS: In a prospective cohort conducted in 3 maternity hospitals in Paris, 882 pregnant women were randomly included between October 12, 2009 and February 3, 2010, with the aim to study characteristics of pandemic influenza during pregnancy. At inclusion, socio-demographic, medical, obstetrical factors and those associated with a higher risk of flu exposition and disease-spreading were systematically collected. Pandemic flu vaccine uptake was checked until delivery. 555 (62.9%) women did not get vaccinated. Determinants associated with non-vaccination in a multivariate logistic regression were: geographic origin (Sub-Saharan African origin, adjusted Odd Ratio aORâ=â5.4[2.3-12.7], North African origin, aORâ=â2.5[1.3-4.7] and Asian origin, aORâ=â2.1[1.7-2.6] compared to French and European origin) and socio-professional categories (farmers, craftsmen and tradesmen, aORâ=â2.3[2.0-2.6], intermediate professionals, aORâ=â1.3[1.0-1.6], employees and manual workers, aORâ=â2.5[1.4-4.4] compared to managers and intellectual professionals). The probability of not receiving pandemic flu vaccine was lower among women vaccinated against seasonal flu in the previous 5 years (aORâ=â0.6[0.4-0.8]) and among those who stopped smoking before or early during pregnancy (aORâ=â0.6[0.4-0.8]). Number of children less than 18 years old living at home, work in contact with children or in healthcare area, or professional contact with the public, were not associated with a higher vaccine uptake. CONCLUSIONS/SIGNIFICANCE: In this cohort of pregnant women, vaccine coverage against pandemic 2009 A/H1N1 flu was low, particularly in immigrant women and those having a low socio-economic status. To improve its effectiveness, future vaccination campaign for pregnant women should be more specifically tailored for these populations
Gender differences in sex life issues â A population-based study of migraine sufferers
<p>Abstract</p> <p>Background</p> <p>Migraine is considered to have a negative influence on sex life. The present study was to analyse the perceptions of importance of and satisfaction with sex life as well as the expression of interest in sex among people having migraines in a prospective follow-up mail survey in 1998 and 2003.</p> <p>Methods</p> <p>The random sample was stratified according to gender and age in four age groups (20â24, 30â34, 40â44, and 50â54 years). Altogether 25 898 individuals responded to the baseline and 19 626 to the follow-up questionnaire (75.8% response rate). We examined as to how the perceptions of sex life of those suffering from migraine changed during a 5-year follow-up. Conditional logistic regression was used to analyse the data of the responses on self-reported migraine in the baseline and follow-up surveys (N = 2 977, 79.2% women). Each person with migraine was assigned a gender- and age-matched control in the analysis.</p> <p>Results</p> <p>All three outcome variables tended to decrease in value. Importance of sex life was higher among men with migraine than among their controls. Among women migraine lessened interest in sex life.</p> <p>Conclusion</p> <p>Our findings suggested that migraine has a different impact on sex life among women from that among men.</p
Vaccination against Heterologous R5 Clade C SHIV: Prevention of Infection and Correlates of Protection
A safe, efficacious vaccine is required to stop the AIDS pandemic. Disappointing results from the STEP trial implied a need to include humoral anti-HIV-1 responses, a notion supported by RV144 trial data even though correlates of protection are unknown. We vaccinated rhesus macaques with recombinant simian immunodeficiency virus (SIV) Gag-Pol particles, HIV-1 Tat and trimeric clade C (HIV-C) gp160, which induced cross-neutralizing antibodies (nAbs) and robust cellular immune responses. After five low-dose mucosal challenges with a simian-human immunodeficiency virus (SHIV) that encoded a heterologous R5 HIV-C envelope (22.1% divergence from the gp160 immunogen), 94% of controls became viremic, whereas one third of vaccinees remained virus-free. Upon high-dose SHIV rechallenge, all controls became infected, whereas some vaccinees remained aviremic. Peak viremia was inversely correlated with both cellular immunity (p<0.001) and cross-nAb titers (p<0.001). These data simultaneously linked cellular as well as humoral immune responses with the degree of protection for the first time
- âŠ