858 research outputs found
Presence and geodynamic significance of Cambro-Ordovician series of SE Karakaram (N. Pakistan)
New geological, geochemical and geochronological data from the Southern Karakoram (NE Pakistan) indicate the presence of several unexpectedly old and well preserved units along the Asian margin: (1) a Precambrian basement, displaying a minimum amphibole Ar-Ar age of 651 Ma; (2) a thick Cambro-Ordovician platform-type sedimentary unit overlying the Precam-brian basement. These series are dated by graptolite and crinoid faunas, and are confirmed by concordant 87Sr/86Sr and 13C âagesâ of the marbles; (3) a dismembered ophiolitic series formed by slices of metagabbros and metabasalts separated by ultramafic lenses (the Masherbrum Greenstone Complex). The occurrence of such Cambro-Ordovician series overlying a Precambrian basement in south-eastern Karakoram similar to the south-western Karakoram shows that the Karakoram constitutes a continuous tectonic block. The petrology and geochemistry of the Masherbrum Greenstone Complex (mineral chemistry, major and trace element and Sr-Nd isotopic data) are indicative of a supra-subductive environment. The presence of LREE-enriched calc-alkaline rocks [(La/Yb)N = 4.45.6; (Nb/La)N = 0.2-0.3; eNd565 = 5.1-7.1] and LREE-depleted tholeiitic rocks [(La/Yb)N =0.5-1.3; (Nb/La)N = 0.6-0.9; eNd565 = 5.6-7.8] are consistent with arc and back-arc settings, respectively. A high-Mg andesitic dolerite and an OIB-type metabasalt, with lower eNd ratios (eNd565 = 0.5 and 4.5) are in accordance with source heterogeneity beneath the arc. The Masherbrum Greenstone Complex, along with other Cambro-Ordovician central-eastern volcanic series give evidence of a tectonic situation governed by micro-plate convergent-divergent systems with occurrence of arc - back-arc settings during the Lower Palaeozoic, comparable to that of the current SW Pacific area
Barley-Ă-glucans reduce systemic inflammation, renal injury and aortic calcification through ADAM17 and neutral-sphingomyelinase2 inhibition
In chronic kidney disease (CKD), hyperphosphatemia-induced inflammation aggravates vascular calcification (VC) by increasing vascular smooth muscle cell (VSMC) osteogenic differentiation, ADAM17-induced renal and vascular injury, and TNFα-induction of neutral-sphingomyelinase2 (nSMase2) to release pro-calcifying exosomes. This study examined anti-inflammatory ÎČ-glucans efficacy at attenuating systemic inflammation in health, and renal and vascular injury favoring VC in hyperphosphatemic CKD. In healthy adults, dietary barley ÎČ-glucans (BÎČglucans) reduced leukocyte superoxide production, inflammatory ADAM17, TNFα, nSMase2, and pro-aging/pro-inflammatory STING (Stimulator of interferon genes) gene expression without decreasing circulating inflammatory cytokines, except for Îł-interferon. In hyperphosphatemic rat CKD, dietary BÎČglucans reduced renal and aortic ADAM17-driven inflammation attenuating CKD-progression (higher GFR and lower serum creatinine, proteinuria, kidney inflammatory infiltration and nSMase2), and TNFα-driven increases in aortic nSMase2 and calcium deposition without improving mineral homeostasis. In VSMC, BÎČglucans prevented LPS- or uremic serum-induced rapid increases in ADAM17, TNFα and nSMase2, and reduced the 13-fold higher calcium deposition induced by prolonged calcifying conditions by inhibiting osteogenic differentiation and increases in nSMase2 through Dectin1-independent actions involving BÎČglucans internalization. Thus, dietary BÎČglucans inhibit leukocyte superoxide production and leukocyte, renal and aortic ADAM17- and nSMase2 gene expression attenuating systemic inflammation in health, and renal injury and aortic calcification despite hyperphosphatemia in CKD.A grant to A.S.D. and M.J.M. from IRBLleida and Agrotecnio Research collaborative projects from the Consell Social at Lleida University supported initial work, Instituto de Salud Carlos III and co-funded by European Union (ERDF/FEDER) (FIS PI11/00259, PI14/01452, PI17/02181), Plan de Ciencia, TecnologĂa e InnovaciĂłn 2013â2017 y 2018â2022 del Principado de Asturias (GRUPIN14-028, IDI-2018-000152), RedInRen from ISCIII (ISCIII-RETIC REDINREN RD16/0009). Investigator support included: NC-L by GRUPIN14-028 and IDI-2018-000152, LM-A by GRUPIN14-028, SP by FICYT; MVA and PV by Educational Grant 2âA/2015 from ERA-EDTA CKD-MBD Working Group; PV and AC by ERA-EDTA fellowships 2011 and 2012; JR-C by MINECO (âJuan de la Ciervaâ program, FJCI-2015-23849); A.S.D. by AsociaciĂłn InvestigaciĂłn de FisiologĂa Aplicada. A.S.D. and M.J.M. are members of the Campus Iberus (Ebro Valley Campus of International Excellence)
Influence of acute kidney injury on short- and long-term outcomes in patients undergoing cardiac surgery: risk factors and prognostic value of a modified RIFLE classification
Introduction: The development of acute kidney injury (AKI) is associated with poor outcome. The modified RIFLE (risk, injury, failure, loss of kidney function, and end-stage renal failure) classification for AKI, which classifies patients with renal replacement therapy needs according to RIFLE failure class, improves the predictive value of AKI in patients undergoing cardiac surgery. Our aim was to assess risk factors for post-operative AKI and the impact of renal function on short- and long-term survival among all AKI subgroups using the modified RIFLE classification. Methods: We prospectively studied 2,940 consecutive cardiosurgical patients between January 2004 and July 2009. AKI was defined according to the modified RIFLE system. Pre-operative, operative and post-operative variables usually measured on and during admission, which included main outcomes, were recorded together with cardiac surgery scores and ICU scores. These data were evaluated for association with AKI and staging in the different RIFLE groups by means of multivariable analyses. Survival was analyzed via Kaplan-Meier and a risk-adjusted Cox proportional hazards regression model. A complete follow-up (mean 6.9â±â4.3 years) was performed in 2,840 patients up to April 2013. Results: Of those patients studied, 14% (nâ=â409) were diagnosed with AKI. We identified one intra-operative (higher cardiopulmonary bypass time) and two post-operative (a longer need for vasoactive drugs and higher arterial lactate 24 hours after admission) predictors of AKI. The worst outcomes, including in-hospital mortality, were associated with the worst RIFLE class. Kaplan-Meier analysis showed survival of 74.9% in the RIFLE risk group, 42.9% in the RIFLE injury group and 22.3% in the RIFLE failure group (P <0.001). Classification at RIFLE injury (Hazard ratio (HR)â=â2.347, 95% confidence interval (CI) 1.122 to 4.907, Pâ=â0.023) and RIFLE failure (HRâ=â3.093, 95% CI 1.460 to 6.550, Pâ=â0.003) were independent predictors for long-term patient mortality. Conclusions: AKI development after cardiac surgery is associated mainly with post-operative variables, which ultimately could lead to a worst RIFLE class. Staging at the RIFLE injury and RIFLE failure class is associated with higher short- and long-term mortality in our population
The Influence of Body Mass Index on Outcomes in Patients Undergoing Cardiac Surgery: Does the Obesity Paradox Really Exist?
Purpose: Obesity influences risk stratification in cardiac surgery in everyday practice. However, some studies have reported better outcomes in patients with a high body mass index (BMI): this is known as the obesity paradox. The aim of this study was to quantify the effect of diverse degrees of high BMI on clinical outcomes after cardiac surgery, and to assess the existence of an obesity paradox in our patients. Methods: A total of 2,499 consecutive patients requiring all types of cardiac surgery with cardiopulmonary bypass between January 2004 and February 2009 were prospectively studied at our institution. Patients were divided into four groups based on BMI: normal weight (18.524.9 kgâmâ2; n = 523; 21.4%), overweight (2529.9kgâmâ2; n = 1150; 47%), obese (â„30â€34.9kgâmâ2; n = 624; 25.5%) and morbidly obese (â„35kgâmâ2; n = 152; 6.2%). Follow-up was performed in 2,379 patients during the first year. Results: After adjusting for confounding factors, patients with higher BMI presented worse oxygenation and better nutritional status, reflected by lower PaO2/FiO2 at 24h and higher albumin levels 48h after admission respectively. Obese patients showed a higher risk for Perioperative Myocardial Infarction (OR: 1.768; 95% CI: 1.0353.022; p = 0.037) and septicaemia (OR: 1.489; 95% CI: 1.2821.997; p = 0.005). In-hospital mortality was 4.8% (n = 118) and 1-year mortality was 10.1% (n = 252). No differences were found regarding in-hospital mortality between BMI groups. The overweight group showed better 1-year survival than normal weight patients (91.2% vs. 87.6%; Log Rank: p = 0.029. HR: 1.496; 95% CI: 1.0622.108; p = 0.021). Conclusions: In our population, obesity increases Perioperative Myocardial Infarction and septicaemia after cardiac surgery, but does not influence in-hospital mortality. Although we found better 1-year survival in overweight patients, our results do not support any protective effect of obesity in patients undergoing cardiac surgery
Evaluation of the PaO2/FiO2 ratio after cardiac surgery as a predictor of outcome during hospital stay
Background: the arterial partial pressure of O2 and the fraction of inspired oxygen (PaO2/FiO2) ratio is widely used in ICUs as an indicator of oxygenation status. Although cardiac surgery and ICU scores can predict mortality, during the first hours after cardiac surgery few instruments are available to assess outcome. The aim of this study was to evaluate the usefulness of PaO2/FIO2 ratio to predict mortality in patients immediately after cardiac surgery. Methods: we prospectively studied 2725 consecutive cardiac surgery patients between 2004 and 2009. PaO2/FiO2 ratio was measured on admission and at 3 h, 6 h, 12 h and 24 h after ICU admission, together with clinical data and outcomes. Results: all PaO2/FIO2 ratio measurements differed between survivors and non-survivors (pââ242; Group 2, with PaO2/FIO2 from 202 to 242; and Group 3, with PaO2/FIO2â<â202. Group 3 showed higher in-ICU mortality and ICU length of stay and Groups 2 and 3 also showed higher respiratory complication rates. The presence of a PaO2/FIO2 ratioâ<â202 at 3 h after admission was shown to be a predictor of in-ICU mortality (OR:1.364; 95% CI:1.212-1.625, pâ<â0.001) and of worse long-term survival (88.8% vs. 95.8%; Log rank pâ=â0.002. Adjusted Hazard ratio: 1.48; 95% CI:1.293-1.786; pâ=â0.004). Conclusions: a simple determination of PaO2/FIO2 at 3 h after ICU admission may be useful to identify patients at risk immediately after cardiac surgery
International Nuclear Medicine Consensus on the Clinical Use of Amyloid Positron Emission Tomography in Alzheimer's Disease.
Alzheimer's disease (AD) is the main cause of dementia, with its diagnosis and management remaining challenging. Amyloid positron emission tomography (PET) has become increasingly important in medical practice for patients with AD. To integrate and update previous guidelines in the field, a task group of experts of several disciplines from multiple countries was assembled, and they revised and approved the content related to the application of amyloid PET in the medical settings of cognitively impaired individuals, focusing on clinical scenarios, patient preparation, administered activities, as well as image acquisition, processing, interpretation and reporting. In addition, expert opinions, practices, and protocols of prominent research institutions performing research on amyloid PET of dementia are integrated. With the increasing availability of amyloid PET imaging, a complete and standard pipeline for the entire examination process is essential for clinical practice. This international consensus and practice guideline will help to promote proper clinical use of amyloid PET imaging in patients with AD
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