223 resultados para Rb fountain frequency standard
Resumo:
Allele frequencies and forensically relevant population statistics of 16 STR loci, including the new European Standard Set (ESS) loci, were estimated from 668 unrelated individuals of Caucasian appearance living in different parts of Switzerland. The samples were amplified with a combination of the following three kits: AmpFlSTR® NGM SElect?, PowerPlex® ESI17 and PowerPlex® ESX 17. All loci were highly polymorphic and no significant departure from Hardy-Weinberg equilibrium and linkage equilibrium was detected after correction for sampling.
Resumo:
Aim: We asked whether myocardial flow reserve (MFR) by Rb-82 cardiac PET improve the selection of patients eligible for invasive coronary angiography (ICA). Material and Methods: We enrolled 26 consecutive patients with suspected or known coronary artery disease who performed dynamic Rb-82 PET/CT and (ICA) within 60 days; 4 patients who underwent revascularization or had any cardiovascular events between PET and ICA were excluded. Myocardial blood flow at rest (rMBF), at stress with adenosine (sMBF) and myocardial flow reserve (MFR=sMBF/rMBF) were estimated using the 1-compartment Lortie model (FlowQuant) for each coronary arteries territories. Stenosis severity was assessed using computer-based automated edge detection (QCA). MFR was divided in 3 groups: G1:MFR<1.5, G2:1.5≤MFR<2 and G3:2≤MFR. Stenosis severity was graded as non-significant (<50% or FFR ≥0.8), intermediate (50%≤stenosis<70%) and severe (≥70%). Correlation between MFR and percentage of stenosis were assessed using a non-parametric Spearman test. Results: In G1 (44 vessels), 17 vessels (39%) had a severe stenosis, 11 (25%) an intermediate one, and 16 (36%) no significant stenosis. In G2 (13 vessels), 2 (15%) vessels presented a severe stenosis, 7 (54%) an intermediate one, and 4 (31%) no significant stenosis. In G3 (9 vessels), 0 vessel presented a severe stenosis, 1 (11%) an intermediate one, and 8 (89%) no significant stenosis. Of note, among 11 patients with 3-vessel low MFR<1.5 (G1), 9/11 (82%) had at least one severe stenosis and 2/11 (18%) had at least one intermediate stenosis. There was a significant inverse correlation between stenosis severity and MFR among all 66 territories analyzed (rho= -0.38, p=0.002). Conclusion: Patients with MFR>2 could avoid ICA. Low MFR (G1, G2) on a vessel-based analysis seems to be a poor predictor of severe stenosis severity. Patients with 3-vessel low MFR would benefit from ICA as they are likely to present a significant stenosis in at least one vessel.
Resumo:
Purpose: To examine the relationship of functional measurements with structural measures. Methods: 146 eyes of 83 test subjects underwent Heidelberg Retinal Tomography (HRTIII) (disc area<2.43, mphsd<40), and perimetry testing with Octopus (SAP; Dynamic), Pulsar (PP; TOP) and Moorfields MDT (ESTA). Glaucoma was defined as progressive structural or functional loss (20 eyes). Perimetry test points were grouped into 6 sectors based on the estimated optic nerve head angle into which the associated nerve fiber bundle enters (Garway-Heath map). Perimetry summary measures (PSM) (MD SAP/ MD PP/ PTD MDT) were calculated from the average total deviation of each measured threshold from the normal for each sector. We calculated the 95% significance level of the sectorial PSM from the respective normative data. We calculated the percentage agreement with group1 (G1), healthy on HRT and within normal perimetric limits, and group 2 (G2), abnormal on HRT and outside normal perimetric limits. We also examined the relationship of PSM and rim area (RA) in those sectors classified as abnormal by MRA (Moorfields Regression Analysis) of HRT. Results: The mean age was 65 (range= [37, 89]). The global sensitivity versus specificity of each instrument in detecting glaucomatous eyes was: MDT 80% vs. 88%, SAP 80% vs. 80%, PP 70% vs. 89% and HRT 80% vs. 79%. Highest percentage agreement of HRT (respectively G1, G2, sector) with PSM were MDT (89%, 57%, nasal superior), SAP (83%, 74%, temporal superior), PP (74%, 63%, nasal superior). Globally percentage agreement (respectively G1, G2) was MDT (92%, 28%), SAP (87%, 40%) and PP (77%, 49%). Linear regression showed there was no significant trend globally associating RA and PSM. However, sectorally the supero-nasal sector had a statistically significant (p<0.001) trend with each instrument, the associated r2 coefficients are (MDT 0.38 SAP 0.56 and PP 0.39). Conclusions: There were no significant differences in global sensitivity or specificity between instruments. Structure-function relationships varied significantly between instruments and were consistently strongest supero-nasally. Further studies are required to investigate these relationships in detail.
Resumo:
We compared the extent and origin of muscle fatigue induced by short-pulse-low-frequency [conventional (CONV)] and wide-pulse-high-frequency (WPHF) neuromuscular electrical stimulation. We expected CONV contractions to mainly originate from depolarization of axonal terminal branches (spatially determined muscle fiber recruitment) and WPHF contractions to be partly produced via a central pathway (motor unit recruitment according to size principle). Greater neuromuscular fatigue was, therefore, expected following CONV compared with WPHF. Fourteen healthy subjects underwent 20 WPHF (1 ms-100 Hz) and CONV (50 μs-25 Hz) evoked isometric triceps surae contractions (work/rest periods 20:40 s) at an initial target of 10% of maximal voluntary contraction (MVC) force. Force-time integral of the 20 evoked contractions (FTI) was used as main index of muscle fatigue; MVC force loss was also quantified. Central and peripheral fatigue were assessed by voluntary activation level and paired stimulation amplitudes, respectively. FTI in WPHF was significantly lower than in CONV (21,717 ± 11,541 vs. 37,958 ± 9,898 N·s P<0,001). The reductions in MVC force (WPHF: -7.0 ± 2.7%; CONV: -6.2 ± 2.5%; P < 0.01) and paired stimulation amplitude (WPHF: -8.0 ± 4.0%; CONV: -7.4 ± 6.1%; P < 0.001) were similar between conditions, whereas no change was observed for voluntary activation level (P > 0.05). Overall, our results showed a different motor unit recruitment pattern between the two neuromuscular electrical stimulation modalities with a lower FTI indicating greater muscle fatigue for WPHF, possibly limiting the presumed benefits for rehabilitation programs.
Resumo:
INTRODUCTION: Quitting smoking is associated with weight gain, which may threaten motivation to engage or sustain a quit attempt. The pattern of weight gained by smokers treated according to smoking cessation guidelines has been poorly described. We aimed to determine the weight gained after smoking cessation and its predictors, by smokers receiving individual counseling and nicotine replacement therapies for smoking cessation. METHODS: We performed an ancillary analysis of a randomized controlled trial assessing moderate physical activity as an aid for smoking cessation in addition to standard treatment in sedentary adult smokers. We used mixed longitudinal models to describe the evolution of weight over time, thus allowing us to take every participant into account. We also fitted a model to assess the effect of smoking status and reported use of nicotine replacement therapy at each time point. We adjusted for intervention group, sex, age, nicotine dependence, and education. RESULTS: In the whole cohort, weight increased in the first 3 months, and stabilized afterwards. Mean 1-year weight gain was 3.3kg for women and 3.9kg for men (p = .002). Higher nicotine dependence and male sex were associated with more weight gained during abstinence. Age over median was associated with continuing weight gain during relapse. There was a nonsignificant trend toward slower weight gain with use of nicotine replacement therapies. CONCLUSION: Sedentary smokers receiving a standard smoking cessation intervention experience a moderate weight gain, limited to the first 3 months. Older age, male sex, and higher nicotine dependence are predictors of weight gain.
Resumo:
Universal standard goniometer is an essential tool to measure articulations' range of motion (ROM). In this time of technological advances and increasing use of smartphones, new measurement's tools appear as specific smartphone applications. This article compares the iOS application "Knee Goniometer" with universal standard goniometer to assess knee ROM. To our knowledge, this is the first study that uses a goniometer application in a clinical context. The purpose of this study is to determine if this application could be used in clinical practice.
Resumo:
Four standard radiation qualities (from RQA 3 to RQA 9) were used to compare the imaging performance of a computed radiography (CR) system (general purpose and high resolution phosphor plates of a Kodak CR 9000 system), a selenium-based direct flat panel detector (Kodak Direct View DR 9000), and a conventional screen-film system (Kodak T-MAT L/RA film with a 3M Trimax Regular screen of speed 400) in conventional radiography. Reference exposure levels were chosen according to the manufacturer's recommendations to be representative of clinical practice (exposure index of 1700 for digital systems and a film optical density of 1.4). With the exception of the RQA 3 beam quality, the exposure levels needed to produce a mean digital signal of 1700 were higher than those needed to obtain a mean film optical density of 1.4. In spite of intense developments in the field of digital detectors, screen-film systems are still very efficient detectors for most of the beam qualities used in radiology. An important outcome of this study is the behavior of the detective quantum efficiency of the digital radiography (DR) system as a function of beam energy. The practice of users to increase beam energy when switching from a screen-film system to a CR system, in order to improve the compromise between patient dose and image quality, might not be appropriate when switching from screen-film to selenium-based DR systems.
Resumo:
The molecular diagnosis of retinal dystrophies (RD) is difficult because of genetic and clinical heterogeneity. Previously, the molecular screening of genes was done one by one, sometimes in a scheme based on the frequency of sequence variants and the number of exons/length of the candidate genes. Payment for these procedures was complicated and the sequential billing of several genes created endless paperwork. We therefore evaluated the costs of generating and sequencing a hybridization-based DNA library enriched for the 64 most frequently mutated genes in RD, called IROme, and compared them to the costs of amplifying and sequencing these genes by the Sanger method. The production cost generated by the high-throughput (HT) sequencing of IROme was established at CHF 2,875.75 per case. Sanger sequencing of the same exons cost CHF 69,399.02. Turnaround time of the analysis was 3 days for IROme. For Sanger sequencing, it could only be estimated, as we never sequenced all 64 genes in one single patient. Sale cost for IROme calculated on the basis of the sale cost of one exon by Sanger sequencing is CHF 8,445.88, which corresponds to the sale price of 40 exons. In conclusion, IROme is cheaper and faster than Sanger sequencing and therefore represents a sound approach for the diagnosis of RD, both scientifically and economically. As a drop in the costs of HT sequencing is anticipated, target resequencing might become the new gold standard in the molecular diagnosis of RD.
Resumo:
Background: Although CD4 cell count monitoring is used to decide when to start antiretroviral therapy in patients with HIV-1 infection, there are no evidence-based recommendations regarding its optimal frequency. It is common practice to monitor every 3 to 6 months, often coupled with viral load monitoring. We developed rules to guide frequency of CD4 cell count monitoring in HIV infection before starting antiretroviral therapy, which we validated retrospectively in patients from the Swiss HIV Cohort Study.Methodology/Principal Findings: We built up two prediction rules ("Snap-shot rule" for a single sample and "Track-shot rule" for multiple determinations) based on a systematic review of published longitudinal analyses of CD4 cell count trajectories. We applied the rules in 2608 untreated patients to classify their 18 061 CD4 counts as either justifiable or superfluous, according to their prior >= 5% or < 5% chance of meeting predetermined thresholds for starting treatment. The percentage of measurements that both rules falsely deemed superfluous never exceeded 5%. Superfluous CD4 determinations represented 4%, 11%, and 39% of all actual determinations for treatment thresholds of 500, 350, and 200x10(6)/L, respectively. The Track-shot rule was only marginally superior to the Snap-shot rule. Both rules lose usefulness for CD4 counts coming near to treatment threshold.Conclusions/Significance: Frequent CD4 count monitoring of patients with CD4 counts well above the threshold for initiating therapy is unlikely to identify patients who require therapy. It appears sufficient to measure CD4 cell count 1 year after a count > 650 for a threshold of 200, > 900 for 350, or > 1150 for 500x10(6)/L, respectively. When CD4 counts fall below these limits, increased monitoring frequency becomes advisable. These rules offer guidance for efficient CD4 monitoring, particularly in resource-limited settings.
Resumo:
Rockfall hazard zoning is usually achieved using a qualitative estimate of hazard, and not an absolute scale. In Switzerland, danger maps, which correspond to a hazard zoning depending on the intensity of the considered phenomenon (e.g. kinetic energy for rockfalls), are replacing hazard maps. Basically, the danger grows with the mean frequency and with the intensity of the rockfall. This principle based on intensity thresholds may also be applied to other intensity threshold values than those used in Switzerland for rockfall hazard zoning method, i.e. danger mapping. In this paper, we explore the effect of slope geometry and rockfall frequency on the rockfall hazard zoning. First, the transition from 2D zoning to 3D zoning based on rockfall trajectory simulation is examined; then, its dependency on slope geometry is emphasized. The spatial extent of hazard zones is examined, showing that limits may vary widely depending on the rockfall frequency. This approach is especially dedicated to highly populated regions, because the hazard zoning has to be very fine in order to delineate the greatest possible territory containing acceptable risks.
Resumo:
PURPOSE: To report feasibility and potential benefits of high-frequency jet ventilation (HFJV) in tumor ablations techniques in liver, kidney, and lung lesions. METHODS: This prospective study included 51 patients (14 women, mean age 66 years) bearing 66 tumors (56 hepatic, 5 pulmonary, 5 renal tumors) with a median size of 16 ± 8.7 mm, referred for tumor ablation in an intention-to-treat fashion before preoperative anesthesiology visit. Cancellation and complications of HFJV were prospectively recorded. Anesthesia and procedure duration, as well as mean CO2 capnea, were recorded. When computed tomography guidance was used, 3D spacial coordinates of an anatomical target <2 mm in diameter on 8 slabs of 4 slices of 3.75-mm slice thickness were registered. RESULTS: HFJV was used in 41 of 51 patients. Of the ten patients who were not candidate for HFJV, two patients had contraindication to HFJV (severe COPD), three had lesions invisible under HFJV requiring deep inspiration apnea for tumor targeting, and five patients could not have HFJV because of unavailability of a trained anesthetic team. No specific complication or hypercapnia related to HFJV were observed despite a mean anesthetic duration of 2 h and ventilation performed in procubitus (n = 4) or lateral decubitus (n = 6). Measured internal target movement was 0.3 mm in x- and y-axis and below the slice thickness of 3.75 mm in the z-axis in 11 patients. CONCLUSIONS: HFJV is feasible in 80 % of patients allowing for near immobility of internal organs during liver, kidney, and lung tumor ablation.
Resumo:
AbstractText BACKGROUND: Profiling sperm DNA present on vaginal swabs taken from rape victims often contributes to identifying and incarcerating rapists. Large amounts of the victim's epithelial cells contaminate the sperm present on swabs, however, and complicate this process. The standard method for obtaining relatively pure sperm DNA from a vaginal swab is to digest the epithelial cells with Proteinase K in order to solubilize the victim's DNA, and to then physically separate the soluble DNA from the intact sperm by pelleting the sperm, removing the victim's fraction, and repeatedly washing the sperm pellet. An alternative approach that does not require washing steps is to digest with Proteinase K, pellet the sperm, remove the victim's fraction, and then digest the residual victim's DNA with a nuclease. METHODS: The nuclease approach has been commercialized in a product, the Erase Sperm Isolation Kit (PTC Labs, Columbia, MO, USA), and five crime laboratories have tested it on semen-spiked female buccal swabs in a direct comparison with their standard methods. Comparisons have also been performed on timed post-coital vaginal swabs and evidence collected from sexual assault cases. RESULTS: For the semen-spiked buccal swabs, Erase outperformed the standard methods in all five laboratories and in most cases was able to provide a clean male profile from buccal swabs spiked with only 1,500 sperm. The vaginal swabs taken after consensual sex and the evidence collected from rape victims showed a similar pattern of Erase providing superior profiles. CONCLUSIONS: In all samples tested, STR profiles of the male DNA fractions obtained with Erase were as good as or better than those obtained using the standard methods.
Resumo:
A previous study has shown the possibility to identify methane (CH4 ) using headspace-GC-MS and quantify it with a stable isotope as internal standard. The main drawback of the GC-MS methods discussed in literature for CH4 measurement is the absence of a specific internal standard necessary to perform quantification. However, it becomes essential to develop a safer method to limit the manipulation of gaseous CH4 and to precisely control the injected amount of gas for spiking and calibration by comparison with external calibration. To avoid the manipulation of a stable isotope-labeled gas, we have chosen to generate a labeled gas as an internal standard in a vial on the basis of the formation of CH4 by the reaction of Grignard reagent methylmagnesium chloride with deuterated water. This method allows precise measurement of CH4 concentrations in gaseous sample as well as in a solid or a liquid sample after a thermodesorption step in a headspace vial. A full accuracy profile validation of this method is then presented.
Resumo:
Background: Medical treatment of inflammatory bowel disease (IBD) is becoming more and more complex, as several classes of immuno-modulating drugs (IMD) are often used simultaneously. Thus, the probability of adverse effects is greatly increased. Most studies reporting on adverse effects focus on single therapy, and studies providing a global survey of side effects for multiple treatments are lacking. Aim: To assess the type and frequency of adverse events in IBD patients treated with single and multiple IMD therapy. Methods: Analysis of data from the Swiss IBD Cohort Study (SIBDCS) that collects data on a large sample of IBD patients from hospitals and private practices across Switzerland. The following IMD categories were analyzed: 5-ASA, azathioprine (Aza), 6-mercaptopurine (6-MP), methotrexate (MTX), anti-TNF (infliximab, adalimumab, certolizumab-pegol), cyclosporine, tacrolimus, and steroids. The following side effects were assessed: hepatitis, pancreatitis, leucopenia, thrombopenia, nephritis, allergic reaction, pneumonitis, infections (including tuberculosis), osteoporosis, abdominal pain/diarrhea (unrelated to IBD activity), cataract, diabetes, exanthema, hirsutism, lupus-like syndrome, myalgias, depression/psychosis, tumor development. Results: A total of 1,961 patients were analyzed (977 [50%] female, mean age 42.1 ± 14.4 years): 1,119 with Crohn's disease (CD), 800 with ulcerative colitis (UC), and 42 with indeterminate colitis (IC). Three-hundred eighteen (16.2%) patients were not treated with any of the above-mentioned medications, while 650 (33.2%), 569 (29%) and 424 (21.6%) patients had one-, two-, and three- or more- IMD therapy, respectively. Of the 1,643 patients treated with IMD, 535 (32.6%) patients reported at least one side effect. We found a significant correlation between the number of drugs used by a patient and the frequency of side effects (17.4% side effects for one drug, 29% for 2 drugs, and 60.6% for three or more drugs, p < 0.001). The frequency of side effects for the different IMD classes were as follows: 5-ASA (n = 980 treated patients) 10.8%, Aza/6-MP (n = 636) 51.9% (pancreatitis in 57 = 9%, hepatitis in 17 = 2.7% of treated patients), MTX (n = 146) 42.5% (hepatitis in 4 = 2.7% of treated patients), anti-TNF (n = 255) 23.1%, cyclosporine (n = 49) 10.2%, tacrolimus (n = 5) 20%, steroids (systemic or topical, n = 1,150) 9.6%. Conclusion: IBD treatment is associated with a significant number of side effects. A direct correlation between the number of IMD used simultaneously and the frequency of side effects was observed. The results of this study indicate that treating physicians should be vigilant for the occurrence of side effects in IBD patients under single and/or multiple drug therapy.
Resumo:
Acute myocarditis was until recently one of the most difficult diagnoses in cardiology. The spectrum of signs and symptoms is very wide, the usual non-invasive tests lack specificity and the myocardial biopsy is only performed in a minority of cases to confirm the diagnosis. Due to its unique ability to directly image myocardial necrosis, fibrosis and oedema, cardiac magnetic resonance (CMR) is now considered the primary tool for noninvasive assessment of patients with suspected myocarditis. CMR is also useful for monitoring disease activity under treatment. Myocarditis has been associated with the development of dilated cardiomyopathy; CMR could play a role in the follow-up of such cases to detect the progression toward a dilatative phenotype. Precise mapping of myocardial lesions with cardiac MRI is invaluable to guide myocardial biopsy and increase its diagnostic yield by improving sensitivity.