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We have developed a high-throughput drug discovery platform, measuring fluorescence resonance energy transfer (FRET) with fluorescent alpha-synuclein (αSN) biosensors, to detect spontaneous pre-fibrillar oligomers in living cells. Our two αSN FRET biosensors provide complementary insight into αSN oligomerization and conformation in order to improve the success of drug discovery campaigns for the treatment of Parkinson’s disease. We measure FRET by fluorescence lifetime, rather than traditional fluorescence intensity, providing a structural readout with greater resolution and precision. This facilitates identification of compounds that cause subtle but significant conformational changes in the ensemble of oligomeric states that are easily missed using intensity-based FRET. We screened a 1280-compound small-molecule library and identified 21 compounds that changed the lifetime by >5 SD. Two of these compounds have nanomolar potency in protecting SH-SY5Y cells from αSN-induced death, providing a nearly tenfold improvement over known inhibitors. We tested the efficacy of several compounds in a primary mouse neuron assay of αSN pathology (phosphorylation of mouse αSN pre-formed fibrils) and show rescue of pathology for two of them. These hits were further characterized with biophysical and biochemical assays to explore potential mechanisms of action. In vitro αSN oligomerization, single-molecule FRET, and protein-observed fluorine NMR experiments demonstrate that these compounds modulate αSN oligomers but not monomers. Subsequent aggregation assays further show that these compounds also deter or block αSN fibril assembly.

Background We report the ability to extend lung preservation up to 24 hours (24H) by using autologous whole donor blood circulating within an ex vivo lung perfusion (EVLP) system. This approach facilitates donor lung reconditioning in a model of extended normothermic EVLP. We analyzed comparative responses to cellular and acellular perfusates to identify these benefits. Methods Twelve pairs of swine lungs were retrieved after cardiac arrest and studied for 24H on the Organ Care System (OCS) Lung EVLP platform. Three groups (n=4 each) were differentiated by perfusate: (1) isolated red blood cells (RBCs) (current clinical standard for OCS); (2) whole blood (WB); and (3) acellular buffered dextran-albumin solution (BDAS, analogous to STEEN solution). Results Only the RBC and WB groups met clinical standards for transplantation at 8 hours; our primary analysis at 24H focused on perfusion with WB versus RBC. The WB perfusate was superior (vs. RBC) for maintaining stability of all monitored parameters, including the following mean 24H measures: pulmonary artery pressure (6.8 vs. 9.0 mmHg), reservoir volume replacement (85 vs. 1607 mL), and PaO2:FiO2 ratio (541 vs. 223). Acellular perfusion was limited to 6 hours on the OCS system due to prohibitively high vascular resistance, edema, and worsening compliance. Conclusions The use of an autologous whole donor blood perfusate allowed 24H of preservation without functional deterioration and was superior to both RBC and BDAS for extended lung preservation in a swine model using OCS Lung. This finding represents a potentially significant advance in donor lung preservation and reconditioning.

In a large, multinational database, the prevalence of masked and sustained hypertension varied across cohorts independent of important comorbidities.

Currently, exercise-based cardiac rehabilitation (CR) is the only recommended secondary prevention strategy for cardiac patients that attempts to tackle stress and psychosocial wellbeing, but it is under-utilized and lacks a comprehensive curriculum for this purpose; hence there is a critical gap to address psychosocial needs of cardiac patients after an event. Mindfulness-based stress reduction (MBSR) has shown benefits in the general population but its role in cardiac patients is not clear. We conducted a pilot randomized controlled trial (RCT) of MBSR in CR-eligible cardiac patients during their initial year of recovery. Patients were allocated 2:1 (intervention:control) to an 8-week MBSR group intervention or usual care. Standard measures of depression, anxiety, perceived stress, health related quality of life (HRQOL), blood pressure, biomarkers (lipids, HbA1c, CRP) and 24-hour Holter monitoring were obtained at baseline, 3- and 9-months post-randomization. Sub-group analyses were performed for participants with at least mild depression (PHQ-9 ≥ 5). 47 patients [mean age 58.6 years; 38% female; 77% white] were enrolled in 2 cohorts. 87% of MBSR patients completed the intervention; study retention was >95% at each follow-up visit. At 3 months, compared to controls, MBSR patients showed improvements in depression [p = 0.01] and anxiety [p = 0.04] with a similar trend in HRQOL [p = 0.06]. The MBSR group showed greater improvement or less worsening of most CV risk factors, with an attenuation of treatment effects at 9 months. Participants with at PHQ-9 scores ≥5 at baseline showed greater improvement in psychosocial and CV outcomes, that persisted at 9 months. MBSR is a safe and well received secondary prevention strategy. This pilot RCT provides preliminary evidence of MBSR’s potential to improve short term psychosocial well-being in cardiac patients during their first year of recovery.

Purpose To clarify the significance of recipient gender status on lung transplant outcomes in a large single institution experience spanning three decades. Methods We analyzed data from all lung transplants performed in our institution since 1986. Kaplan-Meier curves and Cox proportional hazard models were used to evaluate the effect of recipient characteristics on survival and BOS score ≥1-free survival. Logistic regression analysis was used to explore the association of gender with short term graft function. Results 876 lung transplants were performed between 1986 and 2016. Kaplan-Meier survival estimates at 5 years post-transplant for females versus males in the LAS era were 71% versus 58%. In the LAS era females showed greater unadjusted BOS ≥ 1-free survival than males (35% vs 25%, P=0.02] over 5 years. Female gender was the only factor in the LAS era significantly associated with improved adjusted 5 year survival [HR 0.56 (95% CI 0.33, 0.95) P=0.03]. Conversely, in the pre-LAS era female gender was not associated with improved survival. Conclusion Female recipients showed significantly improved survival over 5 years compared to males in the LAS era. A prospective analysis of biologic and immunologic differences is warranted.

Normal subjects can increase their vital capacity by appropriate training. We tested whether that change can be achieved by greater maximal shortening of the inspiratory muscles without concomitant increases in peak static inspiratory pressures. Sixteen healthy volunteers participated in the study: eight were randomly assigned to make 20 inhalations to total lung capacity, held for 10 s with the glottis open, each day for 6 wk; the remainder served as nontraining controls. Before and after the 6-wk study period, we made multiple determinations of lung volumes and of curves relating lung volume to maximal static inspiratory (and expiratory) pressure. Control subjects had no significant changes from base line in any variable. In the training group, the mean vital capacity increased 200 +/- 74 ml (P less than 0.05) or 3.9 +/- 1.3% (P less than 0.02), without a significant change in residual volume. After training, the mean maximal inspiratory pressure at the airway opening (PI) at a lung volume equal to the base-line total lung capacity was 27 +/- 8 cmH2O in this group (vs. zero before training; P less than 0.02). Values of PI in the mid-vital capacity range did not change. We conclude that in response to appropriate training stimuli inspiratory muscles can contract to shorter minimal lengths, a capacity potentially important in progressive pulmonary hyperinflation.

Donation after circulatory death (DCD) is an underused source of donor lungs. Normothermic cellular ex vivo lung perfusion (EVLP) is effective in preserving standard donor lungs but may also be useful in the preservation and assessment of DCD lungs. Using a model of DCD and prolonged EVLP, the effects of donor warm ischemia and postmortem ventilation on graft recovery were evaluated. Adult male swine underwent general anesthesia and heparinization. In the control group (n = 4), cardioplegic arrest was induced and the lungs were procured immediately. In the four treatment groups, a period of agonal hypoxia was followed by either 1 h of warm ischemia with (n = 4) or without (n = 4) ventilation or 2 h of warm ischemia with (n = 4) or without (n = 4) ventilation. All lungs were studied on an EVLP platform for 24 h. Hemodynamic measures, compliance, and oxygenation on EVLP were worse in all DCD lungs compared with controls. Hemodynamics and compliance normalized in all lungs after 24 h of EVLP, but DCD lungs demonstrated impaired oxygenation. Normothermic cellular EVLP is effective in preserving and monitoring of DCD lungs. Early donor postmortem ventilation and timely procurement lead to improved graft function.