In delaying transmission of the cardiac impulse from the atria to the ventricles, the atrioventricular (AV) node serves a critical function in augmenting ventricular filling during diastole and limiting the ventricular response during atrial tachyarrhythmias. The complex structure of the nodal region, however, also provides the substrate for reentrant rhythms. Recent discoveries have elucidated the cellular basis and anatomical determinants of slow conduction in the node. Based on analysis of gap junction proteins, distinct structural components of the AV node have been defined, including the compact node, right and left inferior nodal extensions, the lower nodal bundle, and transitional tissue. Emerging evidence supports the role of the inferior nodal extensions in mediating slow pathway conduction. The most common form of reentry involving the node, slow-fast AV nodal reentrant tachycardia (AVNRT), utilizes the inferior nodal extensions for anterograde slow pathway conduction; the structures responsible for retrograde fast pathway activation in the superior septum are less well defined and likely heterogeneous. Atypical forms of AVNRT arise from circuits that activate at least one of the inferior extensions in the retrograde direction.

Observations suggesting that aeroallergens trigger eosinophilic esophagitis (EoE) in a subset of patients raise questions about the implications this finding has on the evaluation and management of patients with EoE, including a potential role for allergen immunotherapy.

The purpose of this study was to investigate the efficiency of a natural flavonoid, Chrysin (Chr), encapsulated in PLGA-PEG nanoparticles (NPs) for the modulation of macrophage polarity from the pro-inflammatory M1 to anti-inflammatory M2 phenotype. The synthetized NPs were characterized using FTIR, DLS and FE-SEM. MTT assay was used to assess the toxicity of different concentration of Chr-encapsulated NPs on LPS/IFN-γ stimulated peritoneal exudate macrophages. To investigate the repolarization efficiency of Chr-encapsulated NPs, real-time PCR was applied to measure M1 (iNOS and SOCS3) and M2 (Arg1 and Fizz) markers expression. Also, the relative mRNA and protein expression levels of pro-inflammatory cytokines including IL-6, IL-1β and TNF-α were investigated in M1 macrophages treated with Chr-encapsulated NPs. Findings revealed that the Chr-encapsulated NPs with spherical shape and an average diameter of 235 nm were considerably less toxic to the macrophages. Additionally, the nano-formulated Chr efficiently showed a reduction in M1 markers and an increase in M2 markers levels than free Chr. Furthermore, macrophage phenotype switching by PLGA-PEG encapsulated Chr NPs significantly suppressed LPS/IFN-γ induced inflammation by a remarkable reduction in pro-inflammatory cytokine levels, TNF-α, IL-1β, and IL-6. Convincingly, the results revealed that PLGA-PEG encapsulated Chr based drug delivery system might be introduced into biomaterials to fabricate bioactive smart multifunctional nanocomposites with macrophage repolarization activities for regenerative medicine purposes.

Although advances in medical technology and health care have improved the early diagnosis and management for cardiorenal metabolic disorders, the prevalence of obesity, insulin resistance, diabetes, hypertension, dyslipidemia, and kidney disease remains high. Findings from numerous population-based studies, clinical trials, and experimental evidence have consolidated a number of theories for the pathogenesis of cardiorenal metabolic anomalies including resistance to the metabolic action of insulin, abnormal glucose and lipid metabolism, oxidative and nitrosative stress, endoplasmic reticulum (ER) stress, apoptosis, mitochondrial damage, and inflammation. Accumulating evidence has recently suggested a pivotal role for proteotoxicity, the unfavorable effects of poor protein quality control, in the pathophysiology of metabolic dysregulation and related cardiovascular complications. The ubiquitin-proteasome system (UPS) and autophagy-lysosomal pathways, two major although distinct cellular clearance machineries, govern protein quality control by degradation and clearance of long-lived or damaged proteins and organelles. Ample evidence has depicted an important role for protein quality control, particularly autophagy, in the maintenance of metabolic homeostasis. To this end, autophagy offers promising targets for novel strategies to prevent and treat cardiorenal metabolic diseases. Targeting autophagy using pharmacological or natural agents exhibits exciting new strategies for the growing problem of cardiorenal metabolic disorders.

Appropriate neural representation of value and application of decision strategies are necessary to make optimal investment choices in real life. Normative human aging alters neural selectivity and control processing in brain regions implicated in value-based decision processing including striatal, medial temporal, and frontal areas. However, the specific neural mechanisms of how these age-related functional brain changes modulate value processing in older adults remain unclear. Here, young and older adults performed a lottery-choice functional magnetic resonance imaging experiment in which probabilities of winning different magnitudes of points constituted expected values of stakes. Increasing probability of winning modulated striatal responses in young adults, but modulated medial temporal and ventromedial prefrontal areas instead in older adults. Older adults additionally engaged higher responses in dorso-medio-lateral prefrontal cortices to more unfavorable stakes. Such extrastriatal involvement mediated age-related increase in risk-taking decisions. Furthermore, lower resting-state functional connectivity between lateral prefrontal and striatal areas also predicted lottery-choice task risk-taking that was mediated by higher functional connectivity between prefrontal and medial temporal areas during the task, with this mediation relationship being stronger in older than younger adults. Overall, we report evidence of a systemic neural mechanistic change in processing of probability in mixed-lottery values with age that increases risk-taking of unfavorable stakes in older adults. Moreover, individual differences in age-related effects on baseline frontostriatal communication may be a central determinant of such subsequent age differences in value-based decision neural processing and resulting behaviors.

Healthy ageing is a multi-dimensional concept which appertains to all older adults. This study reviewed the intervention characteristics, intervention content and effectiveness of multi-dimensional healthy ageing interventions (MHAIs) addressing physical, mental and social health among independent community-dwelling older adults. A search was conducted in PubMed, CINAHL, Embase, Scopus, and PsycINFO for studies published from Jan 2007 to October 2016. 18 publications were included, accounting for 15 studies. The review reflected the complexity, variations and methodological considerations of developing a comprehensive MHAI. It demonstrated the possibility of integrating person-focused to environment-focused content topics in future MHAIs, beyond the physical, mental and social health dimensions. Among the reviewed studies, health education programs reported improvements in quality of life and life satisfaction while health assessment and education programs promoted positive health behaviors. Future MHAIs studies need to employ more robust research methods and greater contextual information reports to build stronger evidence base.