49 resultados para TESTING 3 HYPOTHESES
Resumo:
Diagnosis of primary ciliary dyskinesia (PCD) lacks a "gold standard" test and is therefore based on combinations of tests including nasal nitric oxide (nNO), high-speed video microscopy analysis (HSVMA), genotyping and transmission electron microscopy (TEM). There are few published data on the accuracy of this approach.Using prospectively collected data from 654 consecutive patients referred for PCD diagnostics we calculated sensitivity and specificity for individual and combination testing strategies. Not all patients underwent all tests.HSVMA had excellent sensitivity and specificity (100% and 93%, respectively). TEM was 100% specific, but 21% of PCD patients had normal ultrastructure. nNO (30 nL·min(-1) cut-off) had good sensitivity and specificity (91% and 96%, respectively). Simultaneous testing using HSVMA and TEM was 100% sensitive and 92% specific.In conclusion, combination testing was found to be a highly accurate approach for diagnosing PCD. HSVMA alone has excellent accuracy, but requires significant expertise, and repeated sampling or cell culture is often needed. TEM alone is specific but misses 21% of cases. nNO (≤30 nL·min(-1)) contributes well to the diagnostic process. In isolation nNO screening at this cut-off would miss ∼10% of cases, but in combination with HSVMA could reduce unnecessary further testing. Standardisation of testing between centres is a future priority.
Resumo:
AIM Anthracycline-induced cardiotoxicity (ACT) occurs in 57% of treated patients and remains an important limitation of anthracycline-based chemotherapy. In various genetic association studies, potential genetic risk markers for ACT have been identified. Therefore, we developed evidence-based clinical practice recommendations for pharmacogenomic testing to further individualize therapy based on ACT risk. METHODS We followed a standard guideline development process; including a systematic literature search, evidence synthesis and critical appraisal, and the development of clinical practice recommendations with an international expert group. RESULTS RARG rs2229774, SLC28A3 rs7853758 and UGT1A6 rs17863783 variants currently have the strongest and the most consistent evidence for association with ACT. Genetic variants in ABCC1, ABCC2, ABCC5, ABCB1, ABCB4, CBR3, RAC2, NCF4, CYBA, GSTP1, CAT, SULT2B1, POR, HAS3, SLC22A7, SCL22A17, HFE and NOS3 have also been associated with ACT, but require additional validation. We recommend pharmacogenomic testing for the RARG rs2229774 (S427L), SLC28A3 rs7853758 (L461L) and UGT1A6*4 rs17863783 (V209V) variants in childhood cancer patients with an indication for doxorubicin or daunorubicin therapy (Level B - moderate). Based on an overall risk stratification, taking into account genetic and clinical risk factors, we recommend a number of management options including increased frequency of echocardiogram monitoring, follow-up, as well as therapeutic options within the current standard of clinical practice. CONCLUSIONS Existing evidence demonstrates that genetic factors have the potential to improve the discrimination between individuals at higher and lower risk of ACT. Genetic testing may therefore support both patient care decisions and evidence development for an improved prevention of ACT.
Resumo:
Analogue modelling experiments using brittle materials are performed to study the inversion of extensional structures. Asymmetric grabens of two different orientations are first created during a phase of extension and progressively filled. They are subsequently shortened in the same direction. The aim of our experiments is to determine factors affecting the style of deformation during inversion. We specifically investigate variations in thickness and distribution of strong and weak layers constituting the graben fill and in initial basin orientation. The main advantage of our experimental set-up is that we have a complete control on graben location, width, infill and orientation before inversion. The experiments show that shortening results only in limited reactivation of pre-existing normal faults. In general, forward thrusts and backthrusts cut across normal faults into the footwall of the graben. The forward thrusts either propagate parallel to the enveloping surface of faulted blocks or they cut across basin-limiting normal faults at various angles. The graben fill is mechanically extruded by displacement along forward thrusts that accommodate most of the shortening. Both pre-existing faults and weak graben fill act as zones of weakness during inversion and determine the orientation and location of both backthrusts and forward thrusts. The results of our experiments conform well to natural examples of inverted graben structures.
Resumo:
QUESTION Detection and treatment of infections during pregnancy are important for both maternal and child health. The objective of this study was to describe testing practices and adherence to current national guidelines in Switzerland. METHODS We invited all registered practicing obstetricians and gynaecologists in Switzerland to complete an anonymous web-based questionnaire about strategies for testing for 14 infections during pregnancy. We conducted a descriptive analysis according to demographic characteristics. RESULTS Of 1138 invited clinicians, 537 (47.2%) responded and 520 (45.6%) were eligible as they are currently caring for pregnant women. Nearly all eligible respondents tested all pregnant women for group B streptococcus (98.0%), hepatitis B virus (HBV) (96.5%) and human immunodeficiency virus (HIV) (94.7%), in accordance with national guidelines. Although testing for toxoplasmosis is not recommended, 24.1% of respondents tested all women and 32.9% tested at the request of the patient. Hospital doctors were more likely not to test for toxoplasmosis than doctors working in private practice (odds ratio [OR] 2.52, 95% confidence interval [CI] 1.04-6.13, p = 0.04). Only 80.4% of respondents tested all women for syphilis. There were regional differences in testing for some infections. The proportion of clinicians testing all women for HIV, HBV and syphilis was lower in Eastern Switzerland and the Zurich region (69.4% and 61.2%, respectively) than in other regions (range 77.1-88.1%, p <0.001). Most respondents (74.5%) said they would appreciate national guidelines about testing for infections during pregnancy. CONCLUSIONS Testing practices for infections in pregnant women vary widely in Switzerland. More extensive national guidelines could improve consistency of testing practices.