Uso de las ecuaciones estructurales en la confirmación de modelos causales haciendo uso del software AMOS versión 19

Un modelo matemático representa cualitativa y/o cuantitativa una parte concreta de la realidad, en el cual se muestran las relaciones predominantes entre sus elementos, sobre los cuales se pueden –y es necesario– realizar previsiones. De acuerdo con Bollen (2002), los fenómenos están influenciados por causas tangibles y elementos no observables (variables latentes). Los Modelos de Ecuaciones Estructurales (SEM, Structural Equation Models), han permitido la contrastación empírica de modelos que incluyen efectos causales entre variables latentes y variables observables; dichos modelos permiten entre otras cosas, la contrastación de teorías a través de la evidencia empírica. El Análisis Factorial Confirmatorio (AFC) es un procedimiento de análisis encuadrado en los modelos de Ecuaciones Estructurales (SEM), cuyo propósito se centra en el estudio de los modelos de medida. En consecuencia, es una estrategia sumamente útil en el ámbito de la prueba de hipótesis y la confirmación de teorías. En el presente trabajo se utilizan modelos de ecuaciones estructurales, concretamente, el análisis factorial confirmatorio, en relación a la validez de las escalas de medida cuando se proponen modelos causales

Drug-induced anaphylaxis, elicitors, risk factors, and management in Latin America

Nonsteroidal anti-inflammatory drugs were the most frequent triggers of drug-induced anaphylaxis in Latín America, whereas antibiotics elicited faster onset and more scvere reactions. An improvement was observed in epinephrinc use and adherence to guidelines in the emergency department treatment of anaphylaxis in Latín America compared with our last report.Facultad de Ciencias Médica

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

Genetic Testing to Inform Epilepsy Treatment Management From an International Study of Clinical Practice

IMPORTANCE: It is currently unknown how often and in which ways a genetic diagnosis given to a patient with epilepsy is associated with clinical management and outcomes. OBJECTIVE: To evaluate how genetic diagnoses in patients with epilepsy are associated with clinical management and outcomes. DESIGN, SETTING, AND PARTICIPANTS: This was a retrospective cross-sectional study of patients referred for multigene panel testing between March 18, 2016, and August 3, 2020, with outcomes reported between May and November 2020. The study setting included a commercial genetic testing laboratory and multicenter clinical practices. Patients with epilepsy, regardless of sociodemographic features, who received a pathogenic/likely pathogenic (P/LP) variant were included in the study. Case report forms were completed by all health care professionals. EXPOSURES: Genetic test results. MAIN OUTCOMES AND MEASURES: Clinical management changes after a genetic diagnosis (ie, 1 P/LP variant in autosomal dominant and X-linked diseases; 2 P/LP variants in autosomal recessive diseases) and subsequent patient outcomes as reported by health care professionals on case report forms. RESULTS: Among 418 patients, median (IQR) age at the time of testing was 4 (1-10) years, with an age range of 0 to 52 years, and 53.8% (n = 225) were female individuals. The mean (SD) time from a genetic test order to case report form completion was 595 (368) days (range, 27-1673 days). A genetic diagnosis was associated with changes in clinical management for 208 patients (49.8%) and usually (81.7% of the time) within 3 months of receiving the result. The most common clinical management changes were the addition of a new medication (78 [21.7%]), the initiation of medication (51 [14.2%]), the referral of a patient to a specialist (48 [13.4%]), vigilance for subclinical or extraneurological disease features (46 [12.8%]), and the cessation of a medication (42 [11.7%]). Among 167 patients with follow-up clinical information available (mean [SD] time, 584 [365] days), 125 (74.9%) reported positive outcomes, 108 (64.7%) reported reduction or elimination of seizures, 37 (22.2%) had decreases in the severity of other clinical signs, and 11 (6.6%) had reduced medication adverse effects. A few patients reported worsening of outcomes, including a decline in their condition (20 [12.0%]), increased seizure frequency (6 [3.6%]), and adverse medication effects (3 [1.8%]). No clinical management changes were reported for 178 patients (42.6%). CONCLUSIONS AND RELEVANCE: Results of this cross-sectional study suggest that genetic testing of individuals with epilepsy may be materially associated with clinical decision-making and improved patient outcomes