365 resultados para Variance monitoring
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Introduction: Recent data have suggested that a population of CD4+ CD25high T cells, phenotypically characterized by the expression of CD45RO and CD127, is significantly expanded in stable liver and kidney transplant recipients and represents alloreactive T cells. Induction therapies may have an impact on this alloreactive T cell population. In this study, we prospectively analyzed CD4+ CD25high CD45RO+ CD127high T cells after induction with either thymoglobulin or basiliximab. Patients & methods: A total of twenty-seven kidney transplant recipients were prospectively enrolled; 14 received thymoglobulin induction followed by a 4-day course of steroids with tacrolimus and mycophenolate mofetil ("thymo group"), and 13 received basiliximab induction followed by standard triple immunosuppression (tacrolimus, mycophenolate mofetil and prednisone) ("BSX group"). Phenotypical analysis by flow cytometry of the expression of CD25, CD45RO and CD127 on peripheral CD4+ T cells was performed at 0, 3 and 6 months after transplantation. Twenty-four healthy subjects (HS) were studied as controls. Results: There were no differences in baseline characteristics between the groups; at 6 months, patient survival (100%), graft survival (100%), serum creatinine (thymo versus BSX group: 129 versus 125 μmol/l) and acute rejection (2/14 versus 2/13) were not significantly different. Thymo induction produced a strong CD4 T cell depletion. As compared to pre-transplantation values, an expansion of the alloreactive T cell population was observed at 3 months in both thymo (mean: from 6.38% to 14.72%) and BSX (from 8.01% to 18.42%) groups. At 6 months, the alloreactive T cell population remained significantly expanded in the thymo group (16.92 ± 2.87%) whereas it tended to decrease in the BSX group (10.22 ± 1.38%). Conclusion: Overall, our results indicate that the expansion of alloreactive T cells occurs rapidly after transplantation in patients receiving either thymo or BSX induction. Whether differences at later timepoints or whether different IS regimens may modify this alloreactive population remains to be studied.
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The hydrogeological properties and responses of a productive aquifer in northeastern Switzerland are investigated. For this purpose, 3D crosshole electrical resistivity tomography (ERT) is used to define the main lithological structures within the aquifer (through static inversion) and to monitor the water infiltration from an adjacent river. During precipitation events and subsequent river flooding, the river water resistivity increases. As a consequence, the electrical characteristics of the infiltrating water can be used as a natural tracer to delineate preferential flow paths and flow velocities. The focus is primarily on the experiment installation, data collection strategy, and the structural characterization of the site and a brief overview of the ERT monitoring results. The monitoring system comprises 18 boreholes each equipped with 10 electrodes straddling the entire thickness of the gravel aquifer. A multi-channel resistivity system programmed to cycle through various four-point electrode configurations of the 180 electrodes in a rolling sequence allows for the measurement of approximately 15,500 apparent resistivity values every 7 h on a continuous basis. The 3D static ERT inversion of data acquired under stable hydrological conditions provides a base model for future time-lapse inversion studies and the means to investigate the resolving capability of our acquisition scheme. In particular, it enables definition of the main lithological structures within the aquifer. The final ERT static model delineates a relatively high-resistivity, low-porosity, intermediate-depth layer throughout the investigated aquifer volume that is consistent with results from well logging and seismic and radar tomography models. The next step will be to define and implement an appropriate time-lapse ERT inversion scheme using the river water as a natural tracer. The main challenge will be to separate the superposed time-varying effects of water table height, temperature, and salinity variations associated with the infiltrating water.
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WE USED A MURINE MODEL OF TRANSIENT FOCAL CEREBRAL ISCHEMIA TO STUDY: 1) in vivo DTI long-term temporal evolution of the apparent diffusion coefficient (ADC) and diffusion fractional anisotropy (FA) at days 4, 10, 15 and 21 after stroke 2) ex vivo distribution of a plasticity-related protein (GAP-43) and its relationship with the ex vivo DTI characteristics of the striato-thalamic pathway (21 days). All animals recovered motor function. In vivo ADC within the infarct was significantly increased after stroke. In the stroke group, GAP-43 expression and FA values were significantly higher in the ipsilateral (IL) striatum and contralateral (CL) hippocampus compared to the shams. DTI tractography showed fiber trajectories connecting the CL striatum to the stroke region, where increased GAP43 and FA were observed and fiber tracts from the CL striatum terminating in the IL hippocampus.Our data demonstrate that DTI changes parallel histological remodeling and recovery of function.
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OBJECTIVE: To compare the heart-rate monitoring with the doubly labelled water (2H2(18)O) method to estimate total daily energy expenditure in obese and non-obese children. DESIGN: Cross sectional study of obese and normal weight children. SUBJECTS: 13 prepubertal children: six obese (4M, 2F, 9.1 +/- 1.5 years, 47.3 +/- 9.7 kg) and seven non-obese (3M, 4F, 9.3 +/- 0.6 years, 31.8 +/- 3.2 kg). MEASUREMENTS: Total daily energy expenditure was assessed by means of the doubly labelled water method (TEEDLW) and of heart-rate monitoring (TEEHR). RESULTS: TEEHR was significantly (P < 0.05) higher than TEEDLW in obese children (9.47 +/- 0.84 MJ/d vs 8.99 +/- 0.63 MJ/d) whereas it was not different in non-obese children (8.43 +/- 2.02 MJ/d vs 8.42 +/- 2.30 MJ/d, P = NS). The difference of TEE assessed by HR monitoring in the obese group averaged 6.2 +/- 4.7%. At the individual level, the degree of agreement (difference between TEEHR and TEEDLW +/- 2s.d.) was low both in obese (-0.36, 1.32 MJ/d) and in non-obese children (-1.30, 1.34 MJ/d). At the group level, the agreement between the two methods was good in nonobese children (95% c.i. for the bias:-0.59, 0.63 MJ/d) but not in obese children (0.04, 0.92 MJ/d). Duration of sleep and energy expenditure during resting and physical activity were not significantly different in the two groups. Patterns of heart-rate (or derived energy expenditure) during the day-time were similar in obese and non-obese children. CONCLUSION: The HR monitoring technique provides an estimation of TEE close to that assessed by the DLW method in non-obese prepubertal children. In comparison with DLW, the HR monitoring method yields a greater TEE value in obese children.
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There is a sustained controversy in the literature about the role and utility of self-monitoring of blood glucose (SMBG) in type 2 diabetes. The study results in this field do not provide really useful clues for the integration of SMBG in the follow-up of the individual patient, because they are based on a misconception of SMBG. It is studied as if it was a medical treatment whose effect on glycemic control is to be isolated. However, SMBG has no such intrinsic effect. It gains its purpose only as an inseparable component of a comprehensive and structured educational strategy. To be appropriate this strategy cannot be based on the health care professionals' view on diabetes only. It rather has to be tailored to the individual patient's needs through an ongoing process of shared reflection with him.
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The Internet is becoming more and more popular among drug users. The use of websites and forums to obtain illicit drugs and relevant information about the means of consumption is a growing phenomenon mainly for new synthetic drugs. Gamma Butyrolactone (GBL), a chemical precursor of Gamma Hydroxy Butyric acid (GHB), is used as a "club drug" and also in drug facilitated sexual assaults. Its market takes place mainly on the Internet through online websites but the structure of the market remains unknown. This research aims to combine digital, physical and chemical information to help understand the distribution routes and the structure of the GBL market. Based on an Internet monitoring process, thirty-nine websites selling GBL, mainly in the Netherlands, were detected between January 2010 and December 2011. Seventeen websites were categorized into six groups based on digital traces (e.g. IP addresses and contact information). In parallel, twenty-five bulk GBL specimens were purchased from sixteen websites for packaging comparisons and carbon isotopic measurements. Packaging information showed a high correlation with digital data confirming the links previously established whereas chemical information revealed undetected links and provided complementary information. Indeed, while digital and packaging data give relevant information about the retailers, the supply routes and the distribution close to the consumer, the carbon isotopic data provides upstream information about the production level and in particular the synthesis pathways and the chemical precursors. A three-level structured market has been thereby identified with a production level mainly located in China and in Germany, an online distribution level mainly hosted in the Netherlands and the customers who order on the Internet.
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BACKGROUND: Current bilevel positive-pressure ventilators for home noninvasive ventilation (NIV) provide physicians with software that records items important for patient monitoring, such as compliance, tidal volume (Vt), and leaks. However, to our knowledge, the validity of this information has not yet been independently assessed. METHODS: Testing was done for seven home ventilators on a bench model adapted to simulate NIV and generate unintentional leaks (ie, other than of the mask exhalation valve). Five levels of leaks were simulated using a computer-driven solenoid valve (0-60 L/min) at different levels of inspiratory pressure (15 and 25 cm H(2)O) and at a fixed expiratory pressure (5 cm H(2)O), for a total of 10 conditions. Bench data were compared with results retrieved from ventilator software for leaks and Vt. RESULTS: For assessing leaks, three of the devices tested were highly reliable, with a small bias (0.3-0.9 L/min), narrow limits of agreement (LA), and high correlations (R(2), 0.993-0.997) when comparing ventilator software and bench results; conversely, for four ventilators, bias ranged from -6.0 L/min to -25.9 L/min, exceeding -10 L/min for two devices, with wide LA and lower correlations (R(2), 0.70-0.98). Bias for leaks increased markedly with the importance of leaks in three devices. Vt was underestimated by all devices, and bias (range, 66-236 mL) increased with higher insufflation pressures. Only two devices had a bias < 100 mL, with all testing conditions considered. CONCLUSIONS: Physicians monitoring patients who use home ventilation must be aware of differences in the estimation of leaks and Vt by ventilator software. Also, leaks are reported in different ways according to the device used.
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pH monitoring has been used as a diagnostic tool in gastro-oesophageal reflux disease (GERD) for many years. Recent studies have shown that wireless capsule pH monitoring is better tolerated and interferes less with daily activities as compared to traditional catheter-based pH monitoring. Moreover, prolonged recording time (48 h instead of 24 h) is possible with wireless pH monitoring. The main secondary effect of wireless capsule pH monitoring is induction of thoracic discomfort in 10-65% of the patients, which can vary from mild foreign body sensation to severe chest pain. Sensitivity and specificity of wireless capsule monitoring is comparable to that of traditional pH monitoring. It has not been proven yet that better tolerability and a longer recording time increases the diagnostic yield of wireless capsule monitoring in GERD.
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rejection can lead to loss of function. Histological reading of endomyocardial biopsy remains the "gold standard" for guiding immunosuppression, despite its methodological limitations (sampling error and interobserver variability). The measurement of the T2 relaxation time has been suggested for detection of allograft rejection, on the pathophysiological basis that the T2 relaxation time prolongs with local edema resulting from acute allograft rejection. Using breath-held cardiac magnetic resonance T2 mapping at 1.5 T, Usman et al. (CircCardiovascImaging2012) detected moderate allograft rejection (grade 2R, ISHLT 2004). With modern immunosuppression grade 2R rejection has become a rare event, but the need remains for a technique that permits the discrimination of absent (grade 0R) and mild rejection (grade 1R). We therefore investigated whether an increase of magnetic field strength to 3T and the use of real-time navigator-gated respiration compensation allow for an increase in the sensitivity of T2 relaxation time detection that is necessary to achieve this discrimination. Methods: Eighteen patients received EMB (Tan et al., ArchPatholLabMed2007) and cardiac T2 mapping on the same day. Reading of T2 maps was blinded to the histological results. For final analysis, 3 cases with known 2R rejection at the time of T2 mapping were added, yielding 21 T2 mapping sessions. A respiration-navigator-gated radial gradient-recalled-echo pulse sequence (resolution 1.17 mm2, matrix 2562, trigger time 3 heartbeats, T2 preparation duration TET2 Prep = 60/30/0 ms) was applied to obtain 3 short-axis T2 maps (van Heeswijk et al., JACCCardiovascImaging2012), which were segmented according to AHA guidelines (Cerqueira et al, Circulation2001). The highest segmental T2 values were grouped according to histological rejection grade and differences were analyzed by Student's t-test, except for the non-blinded cases with 2R rejection. The degree of discrimination was determined using the Spearman's ranked correlation test. Results: The high-quality T2 maps allowed for visual differentiation of the rejection degrees (Figure 1), and the correlation of T2 mapping with the histological grade of acute cellular rejection was significant (Spearman's r = 0.56, p = 0.007). The 0R (n = 15) and 1R (n = 3) degrees demonstrated significantly different T2 values (46.9 ± 5.0 and 54.3 ± 3.0 ms, p = 0.02, Figure 2). Cases with 2R rejection showed clear T2 elevation (T2 = 60.3 ± 16.2 ms). Conclusions: This pilot study demonstrates that non-invasive free-breathing cardiac T2 mapping at 3T discriminates between no and mild cardiac allograft rejection. Confirmation of these encouraging results in a larger cohort should consider a study able to show equivalency or superiority of T2 mapping.
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The Manival near Grenoble (French Prealps) is a very active debris-flow torrent equipped with a large sediment trap (25 000 m3) protecting an urbanized alluvial fan from debris-flows. We began monitoring the sediment budget of the catchment controlled by the trap in Spring 2009. Terrestrial laser scanner is used for monitoring topographic changes in a small gully, the main channel, and the sediment trap. In the main channel, 39 cross-sections are surveyed after every event. Three periods of intense geomorphic activity are documented here. The first was induced by a convective storm in August 2009 which triggered a debris-flow that deposited ~1,800 m3 of sediment in the trap. The debris-flow originated in the upper reach of the main channel and our observations showed that sediment outputs were entirely supplied by channel scouring. Hillslope debris-flows were initiated on talus slopes, as revealed by terrestrial LiDAR resurveys; however they were disconnected to the main channel. The second and third periods of geomorphic activity were induced by long duration and low intensity rainfall events in September and October 2009 which generate small flow events with intense bedload transport. These events contribute to recharge the debris-flow channel with sediments by depositing important gravel dunes propagating from headwaters. The total recharge in the torrent subsequent to bedload transport events was estimated at 34% of the sediment erosion induced by the August debris-flow.
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ABSTRACT: BACKGROUND: An increase in new HIV cases among men who have sex with men (MSM) has been reported in Switzerland since 2001. A rapid result HIV testing for MSM through voluntary counselling and testing (VCT) facility ("Checkpoint") was opened in Geneva in 2005. This gay-friendly facility, the first to open in Switzerland, provides testing for sexually transmitted infections (STI) and rapid result HIV testing and counselling. Our objective was to analyze Checkpoint's activity over its first five years of activity and its ability to attract at-risk MSM. METHODS: We used routine data collected anonymously about the facility activity (number of clients, number of tests, and test results) and about the characteristics of the clientele (sociodemographic data, sexual risk behaviour, and reasons for testing) from 2005 to 2009. RESULTS: The yearly number of HIV tests performed increased from 249 in 2005 to 561 in 2009. The annual proportion of positive tests among tests performed varied between 2% and 3%. Among MSM clients, the median annual number of anal intercourse (AI) partners was three. Roughly 30% of all MSM clients had at least one unprotected anal intercourse (UAI) experience in the previous 12 months with a partner of different/unknown HIV status.The main reason for testing in 2007, 2008, and 2009 was "sexual risk exposure" (~40%), followed by "routine" testing (~30%) and "condom stopping in the beginning of a new steady relationship" (~10%). Clients who came to the facility after a sexual risk exposure, compared to clients who came for "routine testing" or "condom stopping" reasons, had the highest number of AI partners in the previous 12 months, were more likely to have had UAI with a partner of different/unknown HIV status in the previous 12 months (respectively 57.3%, 12.5%, 23.5%), more likely to have had an STI diagnosed in the past (41.6%, 32.2%, 22.9%), and more likely to report recent feelings of sadness or depression (42.6%; 32.8%, 18.5%). CONCLUSION: Many of Checkpoint's clients reported elevated sexual risk exposure and risk factors, and the annual proportion of new HIV cases in the facility is stable. This VCT facility attracts the intended population and appears to be a useful tool contributing to the fight against the HIV epidemic among MSM in Switzerland.
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In October 2011 the Task Force Therapeutic Drug Monitoring of the Association for Neuropsychopharmacology and Pharmacopsychiatry (AGNP) published an update (Pharmacopsychiatry 2011, 44: 195-235) of the first version of the consensus paper on therapeutic drug monitoring (TDM) published in 2004. This article summarizes the essential statements to make them accessible to a wider readership in German speaking countries.
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Five selective serotonin reuptake inhibitors (SSRIs) have been introduced recently: citalopram, fluoxetine, fluvoxamine, paroxetine and sertraline. Although no therapeutic window has been defined for SSRIs, in contrast to tricyclic antidepressants, analytical methods for therapeutic drug monitoring of SSRIs are useful in several instances. SSRIs differ widely in their chemical structure and in their metabolism. The fact that some of them have N-demethylated metabolites, which are also SSRIs, requires that methods be available which allow therapeutic drug monitoring of the parent compounds and of these active metabolites. most procedures are based on prepurification of the SSRIs by liquid-liquid extraction before they are submitted to separation by chromatographic procedures (high-performance liquid chromatography, gas chromatography, thin layer chromatography) and detection by various detectors (UV, fluorescence, electrochemical detector, nitrogen-phosphorus detector, mass spectrometry). This literature review shows that most methods allow quantitative determination of SSRIs in plasma, in the lower ng/ml range, and that they are, therefore, suitable for therapeutic drug monitoring purposes of this category of drugs.