Reactivación de fallas paleozoicas durante la tectónica andina en la Cordillera Oriental-noroeste argentino

Este trabajo fue presentado en el XX Congreso Geológico Argentino, realizado en Tucumán en el año 2017, cuyo título y eje temático fue ¨Ciencias de la Tierra y los recursos naturales del NOA¨. En el Repositorio del SEGEMAR se suben únicamente los trabajos realizados por profesionales de nuestra institución, más cabe la aclaración que los mismos están compilados en un relatorio más amplio, del cual, conjuntamente con el presente trabajo, se adjunta el índice temático y las primeras páginas. La referencia bibliográfica del este relatorio es la siguiente: Muruaga, Claudia Marcela Ciencias de la tierra y recursos naturales del NOA : relatorio del XX Congreso Geológico Argentino / Claudia Marcela Muruaga ; Pablo Grosse. - 1a ed. - San Miguel de Tucumán : Claudia Marcela Muruaga, 2017. Libro digital, PDFFil: Seggiaro, Raúl E. SEGEMAR, Delegación Salta; IBIGEO, UNSa, CONICET y Universidad Nacional de Salta (UNSa); Argentina.Fil: Apaza, Facundo D. Universidad Nacional de Salta (UNSa); Argentina.Fil: Villagrán, Carla A. IBIGEO, UNSa, CONICET; Argentina.Fil: Celedón, Melina R. IBIGEO, UNSa, CONICET; Argentina.Fil: Barrabino, Emilio. IBIGEO, UNSa, CONICET; Argentina.Se presentan ejemplos de fallas paleozoicas reactivadas durante la tectónica andina en un sector de la Cordillera Oriental coincidente con el alto estructural cretácico que confi guró la Dorsal Salto-Jujeña. La ausencia de fallas cretácicas en el área analizada permitió visualizar la infl uencia de la reactivación de fallas paleozoicas en el estilo estructural andino de faja plegada con doble vergencia. Algunas de las secciones que documentan estas estructuras se encuentran en los límites de la Cordillera Oriental y otras en su interior. Del conjunto de estructuras expuestas se destacan fallas paleozoicas normales correspondientes a las fases extensionales ordovícicas y corrimientos generados durante las fases compresivas Oclóyica de fi nes del Ordovícico y/o Chánica del Devónico. Se destaca que los sistemas de corrimientos de la Cordillera Oriental y de las provincias geológicas aledañas Puna y Sistema de Santa Bárbara presentan arquitecturas de fajas plegadas diferentes atribuidas a las estructuras dominantes en el zócalo preandino. Mientras que en la Puna septentrional se documentan fallas paleozoicas reactivadas y fallas cretácicas con inversión tectónica, en la Cordillera Oriental dominan corrimientos reactivados a partir de fallas paleozoicas, sin infl uencia de estructuras cretácicas y en el Sistema de Santa Bárbara septentrional, el estilo estructural está caracterizado principalmente por la inversión de fallas cretácicas. Finalmente se discute el posible control de fallas normales paleozoicas sobre la generación de sistemas de corrimientos andinos con vergencias contrarias a la dirección de transporte tectónico regional. Palabras clave: estilo estructural andino, estructuras reactivadas, deformación precretácica

Elaboración y Síntesis de la Geología

Fil: Servicio Geológico Minero Argentino. Instituto de Geología y Recursos Minerales; Argentina

Clinical and genetic characteristics of late-onset Huntington's disease

Background: The frequency of late-onset Huntington's disease (>59 years) is assumed to be low and the clinical course milder. However, previous literature on late-onset disease is scarce and inconclusive. Objective: Our aim is to study clinical characteristics of late-onset compared to common-onset HD patients in a large cohort of HD patients from the Registry database. Methods: Participants with late- and common-onset (30–50 years)were compared for first clinical symptoms, disease progression, CAG repeat size and family history. Participants with a missing CAG repeat size, a repeat size of ≤35 or a UHDRS motor score of ≤5 were excluded. Results: Of 6007 eligible participants, 687 had late-onset (11.4%) and 3216 (53.5%) common-onset HD. Late-onset (n = 577) had significantly more gait and balance problems as first symptom compared to common-onset (n = 2408) (P <.001). Overall motor and cognitive performance (P <.001) were worse, however only disease motor progression was slower (coefficient, −0.58; SE 0.16; P <.001) compared to the common-onset group. Repeat size was significantly lower in the late-onset (n = 40.8; SD 1.6) compared to common-onset (n = 44.4; SD 2.8) (P <.001). Fewer late-onset patients (n = 451) had a positive family history compared to common-onset (n = 2940) (P <.001). Conclusions: Late-onset patients present more frequently with gait and balance problems as first symptom, and disease progression is not milder compared to common-onset HD patients apart from motor progression. The family history is likely to be negative, which might make diagnosing HD more difficult in this population. However, the balance and gait problems might be helpful in diagnosing HD in elderly patients

The surgical safety checklist and patient outcomes after surgery: a prospective observational cohort study, systematic review and meta-analysis

© 2017 British Journal of Anaesthesia Background: The surgical safety checklist is widely used to improve the quality of perioperative care. However, clinicians continue to debate the clinical effectiveness of this tool. Methods: Prospective analysis of data from the International Surgical Outcomes Study (ISOS), an international observational study of elective in-patient surgery, accompanied by a systematic review and meta-analysis of published literature. The exposure was surgical safety checklist use. The primary outcome was in-hospital mortality and the secondary outcome was postoperative complications. In the ISOS cohort, a multivariable multi-level generalized linear model was used to test associations. To further contextualise these findings, we included the results from the ISOS cohort in a meta-analysis. Results are reported as odds ratios (OR) with 95% confidence intervals. Results: We included 44 814 patients from 497 hospitals in 27 countries in the ISOS analysis. There were 40 245 (89.8%) patients exposed to the checklist, whilst 7508 (16.8%) sustained ≥1 postoperative complications and 207 (0.5%) died before hospital discharge. Checklist exposure was associated with reduced mortality [odds ratio (OR) 0.49 (0.32–0.77); P\u3c0.01], but no difference in complication rates [OR 1.02 (0.88–1.19); P=0.75]. In a systematic review, we screened 3732 records and identified 11 eligible studies of 453 292 patients including the ISOS cohort. Checklist exposure was associated with both reduced postoperative mortality [OR 0.75 (0.62–0.92); P\u3c0.01; I2=87%] and reduced complication rates [OR 0.73 (0.61–0.88); P\u3c0.01; I2=89%). Conclusions: Patients exposed to a surgical safety checklist experience better postoperative outcomes, but this could simply reflect wider quality of care in hospitals where checklist use is routine

Prospective observational cohort study on grading the severity of postoperative complications in global surgery research

Background The Clavien–Dindo classification is perhaps the most widely used approach for reporting postoperative complications in clinical trials. This system classifies complication severity by the treatment provided. However, it is unclear whether the Clavien–Dindo system can be used internationally in studies across differing healthcare systems in high- (HICs) and low- and middle-income countries (LMICs). Methods This was a secondary analysis of the International Surgical Outcomes Study (ISOS), a prospective observational cohort study of elective surgery in adults. Data collection occurred over a 7-day period. Severity of complications was graded using Clavien–Dindo and the simpler ISOS grading (mild, moderate or severe, based on guided investigator judgement). Severity grading was compared using the intraclass correlation coefficient (ICC). Data are presented as frequencies and ICC values (with 95 per cent c.i.). The analysis was stratified by income status of the country, comparing HICs with LMICs. Results A total of 44 814 patients were recruited from 474 hospitals in 27 countries (19 HICs and 8 LMICs). Some 7508 patients (16·8 per cent) experienced at least one postoperative complication, equivalent to 11 664 complications in total. Using the ISOS classification, 5504 of 11 664 complications (47·2 per cent) were graded as mild, 4244 (36·4 per cent) as moderate and 1916 (16·4 per cent) as severe. Using Clavien–Dindo, 6781 of 11 664 complications (58·1 per cent) were graded as I or II, 1740 (14·9 per cent) as III, 2408 (20·6 per cent) as IV and 735 (6·3 per cent) as V. Agreement between classification systems was poor overall (ICC 0·41, 95 per cent c.i. 0·20 to 0·55), and in LMICs (ICC 0·23, 0·05 to 0·38) and HICs (ICC 0·46, 0·25 to 0·59). Conclusion Caution is recommended when using a treatment approach to grade complications in global surgery studies, as this may introduce bias unintentionally

Critical care admission following elective surgery was not associated with survival benefit: prospective analysis of data from 27 countries

This was an investigator initiated study funded by Nestle Health Sciences through an unrestricted research grant, and by a National Institute for Health Research (UK) Professorship held by RP. The study was sponsored by Queen Mary University of London