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Background and Purpose: Diabetes is recognized to enhance the frequency and severity of atherosclerosis and cardiovascular disease. Recent studies have shown that hyperglycemia is associated with enhanced hematopoiesis and macrophage accumulation in atherosclerotic lesions. We explored whether high glucose concentrations can enhance intercellular communication between mature macrophages and hematopoietic progenitors via exosomes to promote inflammation and diabetic atherosclerosis. Methods: Bone marrow derived macrophages (BMDM) from C57BL/6 mice were cultured with normal (5mM) or high glucose concentrations (25mM). Exosomes were isolated with our cushioned-density gradient ultracentrifugation method followed by nanoparticle tracking and western blot analysis. Pro-inflammatory properties of high glucose exosomes (HGexo) were tested in vitro by exposing them to BMDM cultured in normal low glucose. The capacity for BMDM-derived exosomes to alter systemic and vascular inflammation were next tested by infusing 25-30 weeks-old ApoE -/- mice fed a chow diet with 3 x 10 10 exosomes three times a week, for four weeks. Results: Our data show that HGexo can stimulate the expression of inflammatory cytokines (IL-6, IL-1ß) as well as NADPH oxidases (Nox-1 and Nox-4) in cultured BMDM. Furthermore, our findings show that intraperitoneally injected exosomes distribute to numerous organs and tissues including the bone marrow and the spleen. Lastly, HGexo enhance the expansion of multipotent and lineage committed hematopoietic progenitors. Conclusions: We identify that exosomes derived from cultured BMDM exposed to high glucose have the capacity to exert intercellular communication in vitro , and in vivo. Our findings suggest that exosomes produced by macrophages exposed to hyperglycemia could represent an unsuspected source of inflammation to accelerate atherosclerosis in diabetes.

AIMS:We recently reported that immunosuppression with FTY720 improves cardiac function and extends longevity in Hypomorphic ApoE mice deficient in scavenger receptor Type-BI expression, also known as the HypoE/SR-BI(–/–) mouse model of diet-induced coronary atherosclerosis and myocardial infarction (MI). In this study, we tested the impact of FTY720 on cardiac dysfunction in HypoE/SR-BI(–/–) mice that survive MI and subsequently develop chronic heart failure. METHODS/RESULTS:HypoE/SR-BI(–/–) mice were bred to Mx1-Cre transgenic mice, and offspring were fed a high-fat diet (HFD) for 3.5 weeks to provoke hyperlipidemia, coronary atherosclerosis, and recurrent MIs. In contrast to our previous study, hyperlipidemia was rapidly reversed by inducible Cre-mediated gene repair of the HypoE allele and switching mice to a normal chow diet. Mice that survived the period of HFD were subsequently given oral FTY720 in drinking water or not, and left ventricular (LV) function was monitored using serial echocardiography for up to 15 weeks. In untreated mice, LV performance progressively deteriorated. Although FTY720 treatment did not initially prevent a decline of heart function among mice 6 weeks after Cre-mediated gene repair, it almost completely restored normal LV function in these mice by 15 weeks. Reversal of heart failure did not result from reduced atherosclerosis as the burden of aortic and coronary atherosclerosis actually increased to similar levels in both groups of mice. Rather, FTY720 caused systemic immunosuppression as assessed by reduced numbers of circulating T and B lymphocytes. In contrast, FTY720 did not enhance the loss of T cells or macrophages that accumulated in the heart during the HFD feeding period, but it did enhance the loss of B cells soon after plasma lipid lowering. Moreover, FTY720 potently reduced the expression of matrix metalloproteinase-2 and genes involved in innate immunity-associated inflammation in the heart. CONCLUSIONS:Our data demonstrate that immunosuppression with FTY720 prevents postinfarction myocardial remodeling and chronic heart failure.

Patients are living longer with cardiovascular disease managed with antiplatelet drugs. These seniors are asked to be more physically active and are prone to falls or injuries. Few have studied the mortality or morbidity from anticoagulants in patients with traumatic brain injuries (TBI). With the increasing use of clopidogrel in the elderly, studies on the consequences of TBI are warranted.This is a retrospective case-controlled study using a trauma data registry of 3,817 closed head trauma cases (2001-2005). Patients with preinjury use of clopidogrel, aspirin or warfarin, and evidence of traumatic intracranial bleeding were identified (n = 131). These were compared with a frequency-matched control group (n = 178) with similar age, gender, Glasgow Coma Scale, and Injury Severity Scores. Main outcome measure included mortality, hospital or intensive care unit duration, and discharge disposition.Of 131 patients on anticoagulants, patients on clopidogrel (n = 21) were more likely to die (OR = 14.7; 95% CI: 2.3-93.6) and be discharged to an inpatient long-term facility (OR = 3.25; 95%CI: 1.06-9.96). Length of hospital stay and intensive care unit stay were not different from control. Mortality in aspirin patients (n = 90) and warfarin patients (n = 20) did not differ from control. Warfarin patients had increased hospital and ICU stay (10.6 and 5.3 days) when compared with the control (4.7 and 0.9 days, respectively).TBI patients on clopidogrel may have increased long-term disability and fatal consequences when compared with patients who are not on these drugs or on other anticoagulants. Patients on clopidogrel should be advised of safety when engaging in potentially dangerous activities to avoid the consequences of TBI.

Background. Critically ill, extremely premature infants develop anemia because of intensive laboratory blood testing and undergo multiple red blood cell (RBC) transfusions in the early weeks of life. To date, researchers have had only limited success in finding ways to reduce transfusions significantly in this patient population.Objective. To reduce RBC transfusions for these infants by using a point-of-care bedside monitor that returns analyzed blood to the patient.Design, Setting, and Patients. This was a prospective, 2-center, randomized, open, controlled, clinical trial with a 1:1 assignment of extremely low birth weight infants (weighing 500–1000 g at birth) to control or monitor groups and analysis with the intention-to-treat approach. Predefined RBC transfusion criteria were applied uniformly in the 2 groups.Interventions. Clinical treatment of study subjects with an in-line, ex vivo, bedside monitor that withdraws blood through an umbilical artery catheter, analyzes blood gases and sodium, potassium, and hematocrit levels, and returns the sample to the patient.Main Outcome Measures. The total volume and number of RBC transfusions during the first 2 weeks of life and the total volume of blood removed for laboratory testing.Results. The trial was terminated prematurely when one center's NICU changed its standard method of laboratory testing. In the first 2 weeks of life, there was a nonsignificant 17% lower cumulative RBC transfusion volume in the monitor group (n = 46), compared with the control group (n = 47). However, data from the first week only (the period of greater catheter use) demonstrated a significant 33% lower cumulative RBC transfusion volume in the monitor group. Cumulative phlebotomy loss was ∼25% less in the monitor group throughout the 2-week study period. There was no difference between groups in neonatal mortality, morbidity, and neurodevelopmental outcome rates at 18 to 24 months. This is the first randomized trial documenting that RBC transfusions administered to neonates can by reduced by decreasing laboratory phlebotomy loss.Conclusions. As long as an umbilical artery catheter is available for blood sampling with an in-line blood gas and chemistry monitor, significant reductions in neonatal RBC transfusions can be achieved. The patients most likely to benefit from monitor use are the smallest, most critically ill newborns.

A microprocessor-based instrument which integrates the function of a volumetric infusion pump with a blood chemistry analyzer has been developed. Presently, the instrument is capable of measuring Na+, K+, Ca++ and pH within approximately 40 sec at a frequency of up to every 2 min. The system is set up as an intravenous (IV) infusion pump with the addition of an array of disposable sensors placed at the distal end of the IV set. An isotonic IV solution is used to keep the site patent while also serving as a calibrant for the sensors. The instrument first calibrates the sensors, then withdraws approximately 0.6 ml of blood to come in contact with the sensors. Within approximately 15 sec, it displays the results, flushes the blood back into the patient and resumes normal infusion. There is no blood loss to the patient and no need to handle blood. The system was first validated with known aqueous controls and then used on-line in a variety of animal studies where dynamic fluctuation of electrolytes and pH occurred. Excellent correlation was found with off-line samples tested on conventional STAT analyzers. Some preliminary patient data is also presented.

In a previous report, it was shown that a dimension of personality entitled dependence/independence could be used to distinguish the cardiovascular and catecholaminergic response to stress in type A individuals. This study is a continuation of the previous work. It examines the relative effects of beta-blockade on stress-induced changes in heart rate, blood pressure, and catecholamines in two groups of type A individuals who differ in reactivity. Sixty-six healthy, middle-aged men with type A behavior were classified as dependent (high reactivity) or independent (low reactivity). The effects of beta-blockade on the two groups were tested in a randomized, double-blind, crossover trial utilizing a mental stressor, a physical stressor, and work day monitoring. Results showed that, in comparison with the independent type As, those who had been classified as dependent had higher heart rates in all three stress conditions and had higher epinephrine levels during both the mental and physical stressors. For both groups, beta-blockade lowered the heart rate and systolic blood pressure but increased norepinephrine with the mental stressor and epinephrine and norepinephrine with the physical stressor. It also reduced the mean work day heart rate. For the dependent type As, the drug had a greater effect on increasing epinephrine during the physical stressor and by reducing the percent of the work day spent in high heart rate zones. The results are discussed from the point of view of identifying type As who may be particularly coronary prone and the potential effects of beta-blockade on the reactivity associated with type A behavior.