Hypertrophic obstructive cardiomyopathy (HOCM) is one of the more common genetic disorders. The pathophysiology and natural history of the disease have been well studied. Left ventricular outflow ...tract obstruction (LVOTO) and systolic anterior motion (SAM) of the anterior mitral leaflet can result in sudden cardiac death, progressive heart failure and arrythmias. Surgical septal myectomy for HOCM is the standard of care and is routinely performed through a median sternotomy. Septal myectomy has also been performed using the trans‐atrial, trans‐mitral approach either directly or with robotic assistance. In cases with severe LVOT obstruction in the setting of only mild to moderate proximal septal hypertrophy, intrinsic problems with the mitral valve contribute. Typically, these are hypermobile papillary muscles and or excessive height of the anterior mitral leaflet. Combining septal myectomy with reorientation of hypermobile anteriorly positioned papillary muscles has shown to prevent SAM and thereby additionally decrease the subvalvular aortic outflow obstruction. Our extensive experience in both septal myectomy and robotic mitral valve repair has given us a different perspective in approaching the primary mitral regurgitation in HOCM patients where a combined septal myectomy, papillary muscle reorientation and complex mitral valve repair has been safely performed using the less invasive robotic‐assisted approach.Our objective here is to discuss the technical aspects of the procedure.
Adaptive Memory Burns, Daniel J; Burns, Sarah A; Hwang, Ana J
Journal of experimental psychology. Learning, memory, and cognition,
01/2011, Letnik:
37, Številka:
1
Journal Article
Recenzirano
J. S. Nairne, S. R. Thompson, and J. N. S. Pandeirada (2007)
suggested that our memory systems may have evolved to help us remember fitness-relevant information and showed that retention of words ...rated for their relevance to survival is superior to that of words encoded under other deep processing conditions. The authors present 4 experiments that uncover the proximate mechanisms likely responsible. The authors obtained a recall advantage for survival processing compared with conditions that promoted only item-specific processing or only relational processing. This effect was eliminated when control conditions encouraged both item-specific and relational processing. Data from separate measures of item-specific and relational processing generally were consistent with the view that the memorial advantage for survival processing results from the encoding of both types of processing. Although the present study suggests the proximate mechanisms for the effect, the authors argue that survival processing may be fundamentally different from other memory phenomena for which item-specific and relational processing differences have been implicated.
Highlights • A variable polyT variation within TOMM40 was associated with MCI-AD. • TOMM40 genotypes are 97% informative for estimating age of onset risk. • TOMMORROW is a Phase III delay of onset of ...MCI-AD in 65–83 year olds. • Pioglitazone has a large safety experience and used in TOMMORROW. • TOMM40, APOE and age are used to stratify the aged normal population.
This paper considers the control of a multievaporator vapor compression system (ME-VCS) where individual evaporators are permitted to turn ON or OFF. We present a model predictive controller (MPC) ...that can be easily reconfigured for different ON/OFF configurations of the system. In this approach, only the cost function of the constrained finite-time optimal control problem is updated depending on the system configuration. Exploiting the structure of the system dynamics, the cost function is modified by zeroing elements of the state, input, and terminal cost matrices. The advantage of this approach is that cost matrices for each configuration of the ME-VCS do not need to be stored or computed online. This reduces the effort required to tune and calibrate the controller and the amount of memory required to store the controller parameters in a microprocessor. The reconfigurable MPC is compared with a conventional approach in which individual model predictive controllers are independently designed for each ON/OFF configuration. The simulations show that the reconfigurable MPC method provides a similar closed-loop performance in terms of reference tracking and constraint satisfaction to the set of individual model predictive controllers. Further, we show that our controller requires substantially less memory than the alternative approaches. Experiments on a residential two-zone vapor compression system further validate the reconfigurable MPC method.
The underlying genetic and molecular mechanisms that drive amyotrophic lateral sclerosis (ALS) remain poorly understood. Structural variants within the genome can play a significant role in ...neurodegenerative disease risk, such as the repeat expansion in
and the tri-nucleotide repeat in
, both of which are associated with familial and sporadic ALS. Many such structural variants reside in uncharacterized regions of the human genome, and have been under studied. Therefore, characterization of structural variants located in and around genes associated with ALS could provide insight into disease pathogenesis, and lead to the discovery of highly informative genetic tools for stratification in clinical trials. Such genomic variants may provide a deeper understanding of how gene expression can affect disease etiology, disease severity and trajectory, patient response to treatment, and may hold the key to understanding the genetics of sporadic ALS. This article outlines the current understanding of amyotrophic lateral sclerosis genetics and how structural variations may underpin some of the missing heritability of this disease.
Introduction:
Given several reports of an increased neurologic risk with retrograde arterial perfusion in minimally invasive mitral valve surgery, we sought to identify and synthesize the best ...available evidence on the influence of perfusion strategy on post-operative clinical outcomes in this population.
Methods:
A systematic search of PubMed, EMBASE, MEDLINE, and Cochrane library databases was performed to identify publications comparing clinical outcomes associated with antegrade and retrograde arterial perfusion in minimally invasive mitral valve surgery. Pre-specified outcomes of interest were neurologic events, mortality, and renal failure. The search was performed by two independent reviewers, with data abstraction following.
Results:
Seven observational studies were included in this review, with a total patient population of 5,385. Six were retrospective cohort in design, with a single small prospective cohort study identified. When available, adjusted publication-specific risk estimates were abstracted and included preferentially over unadjusted or reviewer-derived risk estimates. Meta-analysis was felt to be heavily flawed in the context of few small studies identified and was not performed. In adjusted estimates, there appeared to be an increased risk of neurologic complications with retrograde arterial perfusion. There was a null pattern apparent between arterial perfusion strategy and each of 30-day mortality and renal failure.
Conclusion:
Retrograde arterial perfusion in minimally invasive mitral valve surgery may be associated with an increased risk of neurologic events, without affecting the risk of 30-day mortality or renal failure. Although these patterns were identified, an overall paucity of evidence justifies further study.
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