New Multidetector Solution Could Lead to Safer Alternatives to Faulty Silicone Breast Implants

The article discusses the effort of the University of Akron\u27s Department of Chemical and Biomolecular Engineering to pursue research which aims to reduce or eliminate capsular contracture associated with breast implants. It notes that the new multidetector nanotechnology developed by researchers can be better alternative to silicone gel-filled breast implants. It mentions that the new technology can also help in early diagnosis and imaging of breast cancer

Effect of Nanoscale Confinement on Glass Transition of Polystyrene Domains from Self-assembly of Block Copolymers

The understanding of size-dependent properties is key to the implementation of nanotechnology. One controversial and unresolved topic is the influence of characteristic size on the glass transition temperature (T(g)) for ultrathin films and other nanoscale geometries. We show that T(g) does depend on size for polystyrene spherical domains with diameters from 20 to 70 nm which are formed from phase separation of diblock copolymers containing a poly(styrene-co-butadiene) soft block and a polystyrene hard block. A comparison of our data with published results on other block copolymer systems indicates that the size dependence of T(g) is a consequence of diffuse interfaces and does not reflect an intrinsic size effect. This is supported by our measurements on 27 nm polystyrene domains in a styrene-isobutylene-styrene triblock copolymer which indicate only a small T(g) depression (3 K) compared to bulk behavior. We expect no effect of size on T(g) in the limit as the solubility parameters of the hard and soft blocks diverge from each other. This strongly segregated limiting behavior agrees with published data for dry and aqueous suspensions of small polystyrene spheres but is in sharp contrast to the strong influence of film thickness on T(g) noted in the literature for free standing ultrathin polystyrene films

Pretreatment with phenoxybenzamine attenuates the radial artery's vasoconstrictor response to α-adrenergic stimuli

AbstractBackgroundAlthough the radial artery bypass conduit has excellent intermediate-term patency, it has a proclivity to vasospasm. We tested the hypothesis that brief pretreatment of a radial artery graft with the irreversible adrenergic antagonist phenoxybenzamine attenuates the vasoconstrictor response to the vasopressors phenylephrine and norepinephrine compared with the currently used papaverine/lidocaine.MethodsSegments of human radial artery grafts were obtained after a 30-minute intraoperative pretreatment with a solution containing 20 mL of heparinized blood, 0.4 mL of papaverine (30 mg/mL), and 1.6 mL of lidocaine (1%). The segments were transported to the laboratory and placed into a bath containing Krebs-Henseleit solution and 10, 100, or 1000 μmol/L phenoxybenzamine or vehicle. The segments were tested in organ chambers for contractile responses to increasing concentrations of phenylephrine and norepinephrine (0.5-15 μmol/L).ResultsContractile responses to 15 μmol/L phenylephrine in control radial artery segments averaged 44.2% ± 9.1% of the maximal contractile response to 30 mmol/L KCl. Papaverine/lidocaine modestly attenuated contraction to 15 μmol/L phenylephrine (32.1% ± 5.9%; P = .22), but 1000 μmol/L phenoxybenzamine completely abolished radial artery contraction (−7.2% ± 4.4%; P < .001). The effect of 10 and 100 μmol/L phenoxybenzamine on attenuating vasocontraction was intermediate between 1000 μmol/L phenoxybenzamine and papaverine/lidocaine. Responses to 15 μmol/L norepinephrine in control radial artery segments averaged 54.7% ± 7.5% of maximal contraction to 30 mmol/L KCl. Papaverine/lidocaine modestly attenuated the contraction response of radial artery segments (35.6% ± 5.1%; P = .04). In contrast, 1000 μmol/L phenoxybenzamine showed the greatest attenuation of norepinephrine-induced contraction (−10.5% ± 2.0%; P < .001).ConclusionsA brief pretreatment of the human radial artery bypass conduit with 1000 μmol/L phenoxybenzamine completely attenuates the vasoconstrictor responses to the widely used vasopressors norepinephrine and phenylephrine. Papaverine/lidocaine alone did not block vasoconstriction to these α-adrenergic agonists

Coronary artery bypass grafting: Part 2—optimizing outcomes and future prospects

Since first introduced in the mid-1960s, coronary artery bypass grafting (CABG) has become the standard of care for patients with coronary artery disease. Surprisingly, the fundamental surgical technique itself did not change much over time. Nevertheless, outcomes after CABG have dramatically improved over the first 50 years. Randomized trials comparing percutaneous coronary intervention (PCI) to CABG have shown converging outcomes for select patient populations, providing more evidence for wider use of PCI. It is increasingly important to focus on the optimization of the short- and long-term outcomes of CABG and to reduce the level of invasiveness of this procedure. This review provides an overview on how new techniques and widespread consideration of evolving strategies have the potential to optimize outcomes after CABG. Such developments include off-pump CABG, clampless/anaortic CABG, minimally invasive CABG with or without extending to hybrid procedures, arterial revascularization, endoscopic vein harvesting, intraprocedural epiaortic scanning, graft flow assessment, and improved secondary prevention measures. In addition, this review represents a framework for future studies by summarizing the areas that need more rigorous clinical (randomized) evaluatio

Endoscopic Saphenous harvesting with an Open CO2 System (ESOS) trial for coronary artery bypass grafting surgery: study protocol for a randomized controlled trial

<p>Abstract</p> <p>Background</p> <p>In coronary artery bypass grafting surgery, arterial conduits are preferred because of more favourable long-term patency and outcome. Anyway <it>the greater saphenous vein </it>continues to be the most commonly used bypass conduit. <it>Minimally invasive endoscopic saphenous vein harvesting </it>is increasingly being investigated in order to reduce the morbidity associated with conventional open vein harvesting, includes postoperative leg wound complications, pain and patient satisfaction. However, to date the short and the long-term benefits of the endoscopic technique remain controversial. This study provides an interesting opportunity to address this gap in the literature.</p> <p>Methods/Design</p> <p><b>Endoscopic Saphenous harvesting with an Open CO₂System </b>trial includes two parallel vein harvesting arms in coronary artery bypass grafting surgery. It is an interventional, single centre, prospective, randomized, safety/efficacy, cost/effectiveness study, in adult patients with elective planned and first isolated coronary artery disease. A simple size of 100 patients for each arm will be required to achieve 80% statistical power, with a significant level of 0.05, for detecting most of the formulated hypotheses. A six-weeks leg wound complications rate was assumed to be 20% in the conventional arm and less of 4% in the endoscopic arm. Previously quoted studies suggest a first-year vein-graft failure rate of about 20% with an annual occlusion rate of 1% to 2% in the first six years, with practically no difference between the endoscopic and conventional approaches. Similarly, the results on event-free survival rates for the two arms have barely a 2-3% gap. Assuming a 10% drop-out rate and a 5% cross-over rate, the goal is to enrol 230 patients from a single Italian cardiac surgery centre.</p> <p>Discussion</p> <p>The goal of this prospective randomized trial is to compare and to test improvement in wound healing, quality of life, safety/efficacy, cost-effectiveness, short and long-term outcomes and vein-graft patency after endoscopic open CO₂harvesting system versus conventional vein harvesting.</p> <p>The expected results are of high clinical relevance and will show the safety/efficacy or non-inferiority of one treatment approach in terms of vein harvesting for coronary artery bypass grafting surgery.</p> <p>Trial registration</p> <p>www.clinicalTrials.gov <a href="http://www.clinicaltrials.gov/ct2/show/NCT01121341">NCT01121341</a>.</p

Evaluation of the PAS-Port Proximal Anastomosis System in coronary artery bypass surgery (the EPIC trial)

ObjectiveDuring coronary surgery, proximal vein graft anastomoses have been performed by using an aortic partial occlusion clamp to allow for a hand-sewn anastomosis. The purpose of this multicenter, prospective, randomized trial was to evaluate the efficacy of the PAS-Port device (Cardica, Inc, Redwood City, Calif), which allows an automated proximal anastomosis to be performed without aortic clamping.MethodsBetween June 22, 2006, and March 22, 2007, 220 patients requiring coronary artery bypass grafting with at least 2 vein grafts were enrolled. Within each patient, 1 graft was randomly assigned to receive a PAS-Port device, and the other was assigned to receive a hand-sewn anastomosis to the ascending aorta. The primary end point was angiographic patency (<50% stenosis) 9 months after surgical intervention. Secondary end points included average time to complete each anastomosis and 9-month freedom from major adverse cardiac events.ResultsOne hundred eighty-three patients received matched grafts that were angiographically assessed at 9 months. The 9-month graft patency was 82.0% (150/183) for hand-sewn and 80.3% (147/183) for PAS-Port grafts. The patency rate of PAS-Port anastomoses was statistically noninferior to that of hand-sewn anastomoses (95% lower confidence limit for difference, −7.95%). The freedom from major adverse cardiac events at 9 months was 97.7% for PAS-Port (95% confidence interval, 94.5%–99.0%) and 98.2% for hand-sewn (95% confidence interval, 95.1%–99.3%) grafts. The PAS-port device was associated with a 4.6 ± 3.9–minute reduction in anastomotic time compared with that seen with a hand-sewn anastomosis (P < .001).ConclusionsThe PAS-Port proximal anastomotic device produces an effective anastomosis with a 9-month patency rate that is comparable with that of a hand-sewn anastomosis. It allows for construction of a proximal anastomosis without aortic clamping and requires less time than a hand-sewn anastomosis

Q134R: Small Chemical Compound with NFAT Inhibitory Properties Improves Behavioral Performance and Synapse Function in Mouse Models of Amyloid Pathology

Inhibition of the protein phosphatase calcineurin (CN) ameliorates pathophysiologic and cognitive changes in aging rodents and mice with aging-related Alzheimer\u27s disease (AD)-like pathology. However, concerns over adverse effects have slowed the transition of common CN-inhibiting drugs to the clinic for the treatment of AD and AD-related disorders. Targeting substrates of CN, like the nuclear factor of activated T cells (NFATs), has been suggested as an alternative, safer approach to CN inhibitors. However, small chemical inhibitors of NFATs have only rarely been described. Here, we investigate a newly developed neuroprotective hydroxyquinoline derivative (Q134R) that suppresses NFAT signaling, without inhibiting CN activity. Q134R partially inhibited NFAT activity in primary rat astrocytes, but did not prevent CN-mediated dephosphorylation of a non-NFAT target, either in vivo, or in vitro. Acute (≤1 week) oral delivery of Q134R to APP/PS1 (12 months old) or wild-type mice (3–4 months old) infused with oligomeric Aβ peptides led to improved Y maze performance. Chronic (≥3 months) oral delivery of Q134R appeared to be safe, and, in fact, promoted survival in wild-type (WT) mice when given for many months beyond middle age. Finally, chronic delivery of Q134R to APP/PS1 mice during the early stages of amyloid pathology (i.e., between 6 and 9 months) tended to reduce signs of glial reactivity, prevented the upregulation of astrocytic NFAT4, and ameliorated deficits in synaptic strength and plasticity, without noticeably altering parenchymal Aβ plaque pathology. The results suggest that Q134R is a promising drug for treating AD and aging-related disorders

Improving coronary artery bypass grafting: a systematic review and meta-analysis on the impact of adopting transit-time flow measurement

Despite there being numerous studies of intraoperative graft flow assessment by transit-time flow measurement (TTFM) on outcomes after coronary artery bypass grafting (CABG), the adoption of contemporary TTFM is low. Therefore, on 31 January 2018, a systematic literature search was performed to identify articles that reported (i) the amount of grafts classified as abnormal or which were revised or (ii) an association between TTFM and outcomes during follow-up. Random-effects models were used to create pooled estimates with 95% confidence intervals (CI) of (i) the rate of graft revision per patient, (ii) the rate of graft revision per graft and (iii) the rate of graft revision among grafts deemed abnormal based on TTFM parameters. The search yielded 242 articles, and 66 original articles were included in the systematic review. Of those articles, 35 studies reported on abnormal grafts or graft revisions (8943 patients, 15 673 grafts) and were included in the meta-analysis. In 4.3% of patients (95% CI 3.3–5.7%, I 2 = 73.9) a revision was required and 2.0% of grafts (95% CI 1.5–2.5%; I 2 = 66.0) were revised. The pooled rate of graft revisions among abnormal grafts was 25.1% (95% CI 15.5–37.9%; I 2 = 80.2). Studies reported sensitivity ranging from 0.250 to 0.457 and the specificity from 0.939 to 0.984. Reported negative predictive values ranged from 0.719 to 0.980 and reported positive predictive values ranged from 0.100 to 0.840. This systematic review and meta-analysis showed that TTFM could improve CABG procedures. However, due to heterogeneous data, drawing uniform conclusions appeared challenging. Future studies should focus on determining the optimal use of TTFM and assessing its diagnostic accuracy