173 resultados para Double cantilever beam


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BACKGROUND: Second line endocrine therapy has limited antitumour activity. Fulvestrant inhibits and downregulates the oestrogen receptor. The mitogen-activated protein kinase (MAPK) pathway is one of the major cascades involved in resistance to endocrine therapy. We assessed the efficacy and safety of fulvestrant with selumetinib, a MEK 1/2 inhibitor, in advanced stage breast cancer progressing after aromatase inhibitor (AI). PATIENTS AND METHODS: This randomised phase II trial included postmenopausal patients with endocrine-sensitive breast cancer. They were ramdomised to fulvestrant combined with selumetinib or placebo. The primary endpoint was disease control rate (DCR) in the experimental arm. ClinicalTrials.gov Indentifier: NCT01160718. RESULTS: Following the planned interim efficacy analysis, recruitment was interrupted after the inclusion of 46 patients (23 in each arm), because the selumetinib-fulvestrant arm did not reach the pre-specified DCR. DCR was 23% (95% confidence interval (CI) 8-45%) in the selumetinib arm and 50% (95% CI 27-75%) in the placebo arm. Median progression-free survival was 3.7months (95% CI 1.9-5.8) in the selumetinib arm and 5.6months (95% CI 3.4-13.6) in the placebo arm. Median time to treatment failure was 5.1 (95% CI 2.3-6.7) and 5.6 (95% CI 3.4-10.2) months, respectively. The most frequent treatment-related adverse events observed in the selumetinib-fulvestrant arm were skin disorders, fatigue, nausea/vomiting, oedema, diarrhoea, mouth disorders and muscle disorders. CONCLUSIONS: The addition of selumetinib to fulvestrant did not show improving patients' outcome and was poorly tolerated at the recommended monotherapy dose. Selumetinib may have deteriorated the efficacy of the endocrine therapy in some patients.

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Reliable molecular typing methods are necessary to investigate the epidemiology of bacterial pathogens. Reference methods such as multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE) are costly and time consuming. Here, we compared our newly developed double-locus sequence typing (DLST) method for Pseudomonas aeruginosa to MLST and PFGE on a collection of 281 isolates. DLST was as discriminatory as MLST and was able to recognize "high-risk" epidemic clones. Both methods were highly congruent. Not surprisingly, a higher discriminatory power was observed with PFGE. In conclusion, being a simple method (single-strand sequencing of only 2 loci), DLST is valuable as a first-line typing tool for epidemiological investigations of P. aeruginosa. Coupled to a more discriminant method like PFGE or whole genome sequencing, it might represent an efficient typing strategy to investigate or prevent outbreaks.

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INTRODUCTION: Apical surgery is an important treatment option for teeth with post-treatment periodontitis. Although apical surgery involves root-end resection, no morphometric data are yet available about root-end resection and its impact on the root-to-crown ratio (RCR). The present study assessed the length of apicectomy and calculated the loss of root length and changes of RCR after apical surgery. METHODS: In a prospective clinical study, cone-beam computed tomography scans were taken preoperatively and postoperatively. From these images, the crown and root lengths of 61 roots (54 teeth in 47 patients) were measured before and after apical surgery. Data were collected relative to the cementoenamel junction (CEJ) as well as to the crestal bone level (CBL). One observer took all measurements twice (to calculate the intraobserver variability), and the means were used for further analysis. The following parameters were assessed for all treated teeth as well as for specific tooth groups: length of root-end resection and percentage change of root length, preoperative and postoperative RCRs, and percentage change of RCR after apical surgery. RESULTS: The mean length of root-end resection was 3.58 ± 1.43 mm (relative to the CBL). This amounted to a loss of 33.2% of clinical and 26% of anatomic root length. There was an overall significant difference between the tooth groups (P < .05). There was also a statistically significant difference comparing mandibular and maxillary teeth (P < .05), but not for incisors/canines versus premolars/molars (P = .125). The mean preoperative and postoperative RCRs (relative to CEJ) were 1.83 and 1.35, respectively (P < .001). With regard to the CBL reference, the mean preoperative and postoperative RCRs were 1.08 and 0.71 (CBL), respectively (P < .001). The calculated changes of RCR after apical surgery were 24.8% relative to CEJ and 33.3% relative to CBL (P < .001). Across the different tooth groups, the mean RCR was not significantly different (P = .244 for CEJ and 0.114 for CBL). CONCLUSIONS: This CBCT-based study demonstrated that the RCR is significantly changed after root-end resection in apical surgery irrespective of the clinical (CBL) or anatomic (CEJ) reference levels. The lowest, and thus clinically most critical, postoperative RCR was observed in maxillary incisors. Future clinical studies need to show the impact of resection length and RCR changes on the outcome of apical surgery.

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PURPOSE: To improve coronary magnetic resonance angiography (MRA) by combining a two-dimensional (2D) spatially selective radiofrequency (RF) pulse with a T2 -preparation module ("2D-T2 -Prep"). METHODS: An adiabatic T2 -Prep was modified so that the first and last pulses were of differing spatial selectivity. The first RF pulse was replaced by a 2D pulse, such that a pencil-beam volume is excited. The last RF pulse remains nonselective, thus restoring the T2 -prepared pencil-beam, while tipping the (formerly longitudinal) magnetization outside of the pencil-beam into the transverse plane, where it is then spoiled. Thus, only a cylinder of T2 -prepared tissue remains for imaging. Numerical simulations were followed by phantom validation and in vivo coronary MRA, where the technique was quantitatively evaluated. Reduced field-of-view (rFoV) images were similarly studied. RESULTS: In vivo, full field-of-view 2D-T2 -Prep significantly improved vessel sharpness as compared to conventional T2 -Prep, without adversely affecting signal-to-noise (SNR) or contrast-to-noise ratios (CNR). It also reduced respiratory motion artifacts. In rFoV images, the SNR, CNR, and vessel sharpness decreased, although scan time reduction was 60%. CONCLUSION: When compared with conventional T2 -Prep, the 2D-T2 -Prep improves vessel sharpness and decreases respiratory ghosting while preserving both SNR and CNR. It may also acquire rFoV images for accelerated data acquisition.

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BACKGROUND: Tuberculosis remains one of the world's deadliest transmissible diseases despite widespread use of the BCG vaccine. MTBVAC is a new live tuberculosis vaccine based on genetically attenuated Mycobacterium tuberculosis that expresses most antigens present in human isolates of M tuberculosis. We aimed to compare the safety of MTBVAC with BCG in healthy adult volunteers. METHODS: We did this single-centre, randomised, double-blind, controlled phase 1 study at the Centre Hospitalier Universitaire Vaudois (CHUV; Lausanne, Switzerland). Volunteers were eligible for inclusion if they were aged 18-45 years, clinically healthy, HIV-negative and tuberculosis-negative, and had no history of active tuberculosis, chemoprophylaxis for tuberculosis, or BCG vaccination. Volunteers fulfilling the inclusion criteria were randomly assigned to three cohorts in a dose-escalation manner. Randomisation was done centrally by the CHUV Pharmacy and treatments were masked from the study team and volunteers. As participants were recruited within each cohort, they were randomly assigned 3:1 to receive MTBVAC or BCG. Of the participants allocated MTBVAC, those in the first cohort received 5 × 10(3) colony forming units (CFU) MTBVAC, those in the second cohort received 5 × 10(4) CFU MTBVAC, and those in the third cohort received 5 × 10(5) CFU MTBVAC. In all cohorts, participants assigned to receive BCG were given 5 × 10(5) CFU BCG. Each participant received a single intradermal injection of their assigned vaccine in 0·1 mL sterile water in their non-dominant arm. The primary outcome was safety in all vaccinated participants. Secondary outcomes included whole blood cell-mediated immune response to live MTBVAC and BCG, and interferon γ release assays (IGRA) of peripheral blood mononuclear cells. This trial is registered with ClinicalTrials.gov, number NCT02013245. FINDINGS: Between Jan 23, 2013, and Nov 6, 2013, we enrolled 36 volunteers into three cohorts, each of which consisted of nine participants who received MTBVAC and three who received BCG. 34 volunteers completed the trial. The safety of vaccination with MTBVAC at all doses was similar to that of BCG, and vaccination did not induce any serious adverse events. All individuals were IGRA negative at the end of follow-up (day 210). After whole blood stimulation with live MTBVAC or BCG, MTBVAC was at least as immunogenic as BCG. At the same dose as BCG (5×10(5) CFU), although no statistical significance could be achieved, there were more responders in the MTBVAC group than in the BCG group, with a greater frequency of polyfunctional CD4+ central memory T cells. INTERPRETATION: To our knowledge, MTBVAC is the first live-attenuated M tuberculosis vaccine to reach clinical assessment, showing similar safety to BCG. MTBVAC seemed to be at least as immunogenic as BCG, but the study was not powered to investigate this outcome. Further plans to use more immunogenicity endpoints in a larger number of volunteers (adults and adolescents) are underway, with the aim to thoroughly characterise and potentially distinguish immunogenicity between MTBVAC and BCG in tuberculosis-endemic countries. Combined with an excellent safety profile, these data support advanced clinical development in high-burden tuberculosis endemic countries. FUNDING: Biofabri and Bill & Melinda Gates Foundation through the TuBerculosis Vaccine Initiative (TBVI).

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Despite the development of novel typing methods based on whole genome sequencing, most laboratories still rely on classical molecular methods for outbreak investigation or surveillance. Reference methods for Clostridium difficile include ribotyping and pulsed-field gel electrophoresis, which are band-comparing methods often difficult to establish and which require reference strain collections. Here, we present the double locus sequence typing (DLST) scheme as a tool to analyse C. difficile isolates. Using a collection of clinical C. difficile isolates recovered during a 1-year period, we evaluated the performance of DLST and compared the results to multilocus sequence typing (MLST), a sequence-based method that has been used to study the structure of bacterial populations and highlight major clones. DLST had a higher discriminatory power compared to MLST (Simpson's index of diversity of 0.979 versus 0.965) and successfully identified all isolates of the study (100 % typeability). Previous studies showed that the discriminatory power of ribotyping was comparable to that of MLST; thus, DLST might be more discriminatory than ribotyping. DLST is easy to establish and provides several advantages, including absence of DNA extraction [polymerase chain reaction (PCR) is performed on colonies], no specific instrumentation, low cost and unambiguous definition of types. Moreover, the implementation of a DLST typing scheme on an Internet database, such as that previously done for Staphylococcus aureus and Pseudomonas aeruginosa ( http://www.dlst.org ), will allow users to easily obtain the DLST type by submitting directly sequencing files and will avoid problems associated with multiple databases.

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PURPOSE: To assess the circadian variations in salivary immunoglobin A (sIgA) and alpha-amylase activity (sAA), biomarkers of mucosal immune function, together with mood during 2 weeks of repeated sprint training in hypoxia (RSH) and normoxia (RSN). METHODS: Over a 2-week period, 17 competitive cross-country skiers performed six training sessions, each consisting of four sets of five 10-s bouts of all-out double-poling under either normobaric hypoxia (FiO2: 13.8 %, 3000 m) or normoxia. The levels of sIgA and sAA activity and mood were determined five times during each of the first (T1) and sixth (T6) days of training, as well as during days preceding (baseline) and after the training intervention (follow-up). RESULTS: With RSH, sIgA was higher on T6 than T1 (P = 0.049), and sAA was increased on days T1, T6, and during the follow-up (P < 0.01). With RSN, sIgA remained unchanged and sAA was elevated on day T1 only (P = 0.04). Similarly, the RSH group demonstrated reduced mood on days T1, T6, and during the follow-up, while mood was lowered only on T1 with RSN (P < 0.01). CONCLUSIONS: The circadian variation of sIgA and sAA activity, biomarkers of mucosal immune function, as well as mood were similar on the first day of training when repeated double-poling sprints were performed with or without hypoxia. Only with RSH did the levels of sIgA and sAA activity rise with time, becoming maximal after six training sessions, when mood was still lowered. Therefore, six sessions of RSH reduced mood, but did not impair mucosal immune function.