12 research outputs found

    The earliest evidence for Upper Paleolithic occupation in the Armenian Highlands at Aghitu-3 Cave

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    With its well-preserved archaeological and environmental records, Aghitu-3 Cave permits us to examine the settlement patterns of the Upper Paleolithic (UP) people who inhabited the Armenian Highlands. We also test whether settlement of the region between ∌39–24,000 cal BP relates to environmental variability. The earliest evidence occurs in archaeological horizon (AH) VII from ∌39–36,000 cal BP during a mild, moist climatic phase. AH VI shows periodic occupation as warm, humid conditions prevailed from ∌36–32,000 cal BP. As the climate becomes cooler and drier at ∌32– 29,000 cal BP (AH V-IV), evidence for occupation is minimal. However, as cooling continues, the deposits of AH III demonstrate that people used the site more intensively from ∌29–24,000 cal BP, leaving behind numerous stone artifacts, faunal remains, and complex combustion features. Despite the climatic fluctuations seen across this 15,000-year sequence, lithic technology remains attuned to one pattern: unidirectional reduction of small cores geared towards the production of bladelets for tool manufacture. Subsistence patterns also remain stable, focused on medium-sized prey such as ovids and caprids, as well as equids. AH III demonstrates an expansion of social networks to the northwest and southwest, as the transport distance of obsidian used to make stone artifacts increases. We also observe the addition of bone tools, including an eyed needle, and shell beads brought from the east, suggesting that these people manufactured complex clothing and wore ornaments. Remains of micromammals, birds, charcoal, pollen, and tephra relate the story of environmental variability. We hypothesize that UP behavior was linked to shifts in demographic pressures and climatic changes. Thus, by combining archaeological and environmental data, we gain a clearer picture about the first UP inhabitants of the Armenian Highlands

    Short-term occupations at high elevation during the Middle Paleolithic at Kalavan 2 (Republic of Armenia)

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    The Armenian highlands encompasses rugged and environmentally diverse landscapes and is characterized by a mosaic of distinct ecological niches and large temperature gradients. Strong seasonal fluctuations in resource availability along topographic gradients likely prompted Pleistocene hominin groups to adapt by adjusting their mobility strategies. However, the role that elevated landscapes played in hunter-gatherer settlement systems during the Late Pleistocene (Middle Palaeolithic [MP]) remains poorly understood. At 1640 m above sea level, the MP site of Kalavan 2 (Armenia) is ideally positioned for testing hypotheses involving elevation-dependent seasonal mobility and subsistence strategies. Renewed excavations at Kalavan 2 exposed three main occupation horizons and ten additional low densities lithic and faunal assemblages. The results provide a new chronological, stratigraphical, and paleoenvironmental framework for hominin behaviors between ca. 60 to 45 ka. The evidence presented suggests that the stratified occupations at Kalavan 2 locale were repeated ephemerally most likely related to hunting in a high-elevation within the mountainous steppe landscape.info:eu-repo/semantics/publishedVersio

    Impact of Diabetes Mellitus and Chronic Kidney Disease on Cardiovascular Outcomes and Platelet P2Y(12) Receptor Antagonist Effects in Patients With Acute Coronary Syndromes : Insights From the PLATO Trial

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    Background-There are limited data on how the combination of diabetes mellitus (DM) and chronic kidney disease (CKD) affects cardiovascular outcomes as well as response to different P2Y(12) receptor antagonists, which represented the aim of the present investigation. Methods and Results-In this post hoc analysis of the PLATO (Platelet Inhibition and Patient Outcomes) trial, which randomized acute coronary syndrome patients to ticagrelor versus clopidogrel, patients (n=15 108) with available DM and CKD status were classified into 4 groups: DM+/CKD+ (n=1058), DM+/CKD- (n=2748), DM-/CKD+ (n=2160), and DM-/CKD- (n=9142). The primary efficacy end point was a composite of cardiovascular death, myocardial infarction, or stroke at 12 months. The primary safety end point was PLATO major bleeding. DM+/CKD+ patients had a higher incidence of the primary end point compared with DM-/CKD- patients (23.3% versus 7.1%; adjusted hazard ratio 2.22; 95% CI 1.88-2.63; P Conclusions-In acute coronary syndrome patients, a gradient of risk was observed according to the presence or absence of DM and CKD, with patients having both risk factors at the highest risk. Although the ischemic benefit of ticagrelor over clopidogrel was consistent in all subgroups, the absolute risk reduction was greatest in patients with both DM and CKD.Peer reviewe

    Differential effect of clopidogrel and ticagrelor on leukocyte count in relation to patient characteristics, biomarkers and genotype : a PLATO substudy.

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    Inflammation plays a key role in cardiovascular disease by contributing to atherothrombosis. The PLATelet inhibition and patient Outcomes (PLATO) study (NCT00391872) compared ticagrelor to clopidogrel in patients with acute coronary syndromes and demonstrated fewer cardiovascular events with ticagrelor but lower white blood cell counts (WBC) with clopidogrel. In this further analysis of the PLATO biomarker substudy, we assessed associations between WBC and clinical characteristics, biomarker levels, and CYP2C19 polymorphisms.On-treatment mean (SD) WBC in the clopidogrel group was mildly reduced at each stage of follow-up compared with either the ticagrelor group (1 month: 7.27 (2.1) and 7.67 (2.23) x109/L for clopidogrel and ticagrelor, respectively; p < .001) or following cessation of clopidogrel (7.23 (1.97) x109/L, at 6 months vs 7.56 (2.28) x109/L after treatment cessation; P < .001). This occurred independently of baseline biomarkers and CYP2C19 genotype (where known). Adjusting for clinical characteristics and other biomarkers, no significant interaction was detected between clinical risk factors and the observed effect of clopidogrel on WBC.Clopidogrel weakly suppresses WBC, independent of clinical characteristics, baseline inflammatory biomarker levels, and CYP2C19 genotype. Further work is required to determine the mechanism for this effect and whether it contributes to clopidogrel's efficacy as well as therapeutic interaction with anti-inflammatory drugs

    Biomarker Concentrations and Their Temporal Changes in Patients With Myocardial Infarction and Nonobstructive Compared With Obstructive Coronary Arteries : Results From the PLATO Trial

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    Background: The pathobiology of myocardial infarction (MI) with nonobstructive coronary arteries (MINOCA) is often uncertain. Investigating biomarker concentrations and their changes may offer novel pathophysiological insights. Methods and Results: In this post hoc study of the PLATO (Platelet Inhibition and Patient Outcomes) trial, concentrations of hs‐cTnT (high‐sensitivity cardiac troponin T), NT‐proBNP (N‐terminal pro‐B‐type natriuretic peptide), hs‐CRP (high‐sensitivity C‐reactive protein), and GDF‐15 (growth differentiation factor 15) were measured in patients with MINOCA at baseline (n=554) and at 1‐month follow‐up (n=107). For comparisons, biomarkers were also measured in patients with MI with obstructive (stenosis ≄50%) coronary artery disease (baseline: n=11 106; follow‐up: n=2755]). Adjusted linear regression models were used to compare concentrations and their short‐ and long‐term changes. The adjusted geometric mean ratios (GMRs) in patients with MINOCA (median age, 61 years; 50.4% women) indicated lower hs‐cTnT (GMR, 0.77 [95% CI, 0.68–0.88]) but higher hs‐CRP (GMR, 1.21 [95% CI, 1.08–1.37]) and GDF‐15 concentrations (GMR, 1.06 [95% CI, 1.02–1.11]) at baseline compared with patients with MI with obstructive coronary artery disease, whereas NT‐proBNP concentrations were similar. Temporal decreases in hs‐cTnT, NT‐proBNP, and hs‐CRP concentrations until 1‐month follow‐up were more pronounced in patients with MINOCA. At follow‐up, patients with MINOCA had lower concentrations of hs‐cTnT (GMR, 0.71 [95% CI, 0.60–0.84]), NT‐proBNP (GMR, 0.45 [95% CI, 0.36–0.56]), and hs‐CRP (GMR, 0.68 [95% CI, 0.53–0.86]). One‐month GDF‐15 concentrations were similar between both groups with MI. Conclusions: Biomarker concentrations suggest greater initial inflammatory activity, similar degree of myocardial dysfunction, and less pronounced myocardial injury during the acute phase of MINOCA compared with MI with obstructive coronary artery disease but also faster myocardial recovery. CLINICAL TRAIL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00391872.Title in dissertation list of papers: Biomarker concentrations and their temporal changes in myocardial infarction patients with non-obstructive compared to obstructive coronary arteries: results from the PLATelet inhibition and patient Outcomes (PLATO) trial</p

    C-X-C ligand 16 is an independent predictor of cardiovascular death and morbidity in acute coronary syndromes

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    Objective: - The chemokine CXCL16 (C-X-C motif ligand 16) is a scavenger receptor for OxLDL (oxidized low-density lipoproteins) and involved in inflammation at sites of atherosclerosis. This study aimed to investigate the association of CXCL16 with clinical outcome in patients with acute coronary syndrome. Approach and Results: - Serial measurements of CXCL16 were performed in a subgroup of 5142 patients randomized in the PLATO trial (Platelet Inhibition and Patient Outcome). Associations between CXCL16 and a composite of cardiovascular death, spontaneous myocardial infarction or stroke, and the individual components were assessed by multivariable Cox regression analyses. The hazard ratio per 50% increase in admission levels of CXCL16 analyzed as continuous variable was 1.64 (95% CI, 1.44–1.88), PP=0.0126. The admission level of CXCL16 was independently associated with cardiovascular death (1.50 [1.17–1.92], P=0.0014) but not with ischemic events alone, in fully adjusted analyses. No statistically independent association was found between CXCL16 measured at 1 month, or change in CXCL16 from admission to 1 month, and clinical outcomes. Conclusions: - In patients with acute coronary syndrome, admission level of CXCL16 is independently related to adverse clinical outcomes, mainly driven by an association to cardiovascular death. Thus, CXCL16 measurement may enhance risk stratification in patients with this condition

    ALCAM predicts future cardiovascular death in acute coronary syndromes: Insights from the PLATO trial

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    Background and aims - Activated leukocyte cell adhesion molecule (ALCAM) is upregulated during inflammation and involved in transmigration of leukocytes and T-cell activation. We hypothesized that ALCAM might be associated with recurrent events in patients with acute coronary syndromes (ACS). Methods - ALCAM was measured in serum obtained on admission, at discharge, 1 month and 6 months in a subgroup of 5165 patients admitted with ACS and included in the PLATelet inhibition and patient Outcomes (PLATO) trial (NCT00391872). The association between ALCAM and the composite endpoint and its components, including cardiovascular (CV) death, non-procedural spontaneous myocardial infarction (MI) or stroke during 1-year follow-up, was assessed by Cox proportional hazards models with incremental addition of clinical risk factors and biomarkers (including high-sensitivity troponin T, N-terminal pro−B-type natriuretic peptide and growth differentiation factor-15). Results - The median (Q1-Q3) concentration of ALCAM at admission was 97 (80–116) ng/mL. A 50% higher level of ALCAM on admission was associated with a hazard ratio (HR) of 1.16 (95% confidence interval [1.00–1.34] p = 0.043) for the composite endpoint in fully adjusted analysis, mainly driven by the association with CV death (HR 1.45 [1.16–1.82] p = 0.0012). Conclusions - In patients with ACS, admission level of ALCAM was independently associated with adverse outcome including CV death even after adjustment for established inflammatory and cardiac biomarkers
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