Individual Patient Data Meta-Analysis of Dynamic Cerebral Autoregulation and Functional Outcome After Ischemic Stroke.

BACKGROUND: The relationship between dynamic cerebral autoregulation (dCA) and functional outcome after acute ischemic stroke (AIS) is unclear. Previous studies are limited by small sample sizes and heterogeneity. METHODS: We performed a 1-stage individual patient data meta-analysis to investigate associations between dCA and functional outcome after AIS. Participating centers were identified through a systematic search of the literature and direct invitation. We included centers with dCA data within 1 year of AIS in adults aged over 18 years, excluding intracerebral or subarachnoid hemorrhage. Data were obtained on phase, gain, coherence, and autoregulation index derived from transfer function analysis at low-frequency and very low-frequency bands. Cerebral blood velocity, arterial pressure, end-tidal carbon dioxide, heart rate, stroke severity and sub-type, and comorbidities were collected where available. Data were grouped into 4 time points after AIS: <24 hours, 24 to 72 hours, 4 to 7 days, and >3 months. The modified Rankin Scale assessed functional outcome at 3 months. Modified Rankin Scale was analyzed as both dichotomized (0 to 2 versus 3 to 6) and ordinal (modified Rankin Scale scores, 0-6) outcomes. Univariable and multivariable analyses were conducted to identify significant relationships between dCA parameters, comorbidities, and outcomes, for each time point using generalized linear (dichotomized outcome), or cumulative link (ordinal outcome) mixed models. The participating center was modeled as a random intercept to generate odds ratios with 95% CIs. RESULTS: The sample included 384 individuals (35% women) from 7 centers, aged 66.3±13.7 years, with predominantly nonlacunar stroke (n=348, 69%). In the affected hemisphere, higher phase at very low-frequency predicted better outcome (dichotomized modified Rankin Scale) at <24 (crude odds ratios, 2.17 [95% CI, 1.47-3.19]; P<0.001) hours, 24-72 (crude odds ratios, 1.95 [95% CI, 1.21-3.13]; P=0.006) hours, and phase at low-frequency predicted outcome at 3 (crude odds ratios, 3.03 [95% CI, 1.10-8.33]; P=0.032) months. These results remained after covariate adjustment. CONCLUSIONS: Greater transfer function analysis-derived phase was associated with improved functional outcome at 3 months after AIS. dCA parameters in the early phase of AIS may help to predict functional outcome.

TEM Classification of Aortic Dissection-The Evolving Scoring System: A Literature Review.

Aortic dissection is an acute presentation that, if unnoticed, poses a significant risk to life. Anatomically, it is defined as a tear in the intimal layer of the aorta, but management differs significantly based on the location of this tear. Traditionally the Stanford and DeBakey classifications have been used to distinguish tear types and thus guide the most favourable management option, be it medical optimisation or surgery. Recently, a new Type-Entry-Malperfusion classification has been proposed to more accurately define and thus risk stratify patients with aortic dissection. This review summarises the Type-Entry-Malperfusion classification and highlights its potential advantages and limitations compared to other classifications. Clinical insights and potential barriers to adopting this classification are also described in this review.

Unveiling the Effect of Superlattice Interfaces and Intermixing on Phase Change Memory Performance.

Superlattice (SL) phase change materials have shown promise to reduce the switching current and resistance drift of phase change memory (PCM). However, the effects of internal SL interfaces and intermixing on PCM performance remain unexplored, although these are essential to understand and ensure reliable memory operation. Here, using nanometer-thin layers of Ge2Sb2Te5 and Sb2Te3 in SL-PCM, we uncover that both switching current density (Jreset) and resistance drift coefficient (v) decrease as the SL period thickness is reduced (i.e., higher interface density); however, interface intermixing within the SL increases both. The signatures of distinct versus intermixed interfaces also show up in transmission electron microscopy, X-ray diffraction, and thermal conductivity measurements of our SL films. Combining the lessons learned, we simultaneously achieve low Jreset ≈ 3-4 MA/cm2 and ultralow v ≈ 0.002 in mushroom-cell SL-PCM with ∼110 nm bottom contact diameter, thus advancing SL-PCM technology for high-density storage and neuromorphic applications.

Effects of music interventions on sleep in older adults: A systematic review.

Sleep disruption is common among older adults. Non-pharmacological interventions involving music has emerged as a promising approach to address sleep disruption. The purpose of this systematic review was to examine the effects of music interventions on sleep outcomes among older adults (age ≥ 50). We searched five databases through May 2020 and found 16 eligible studies focused on two types of music interventions: music listening (n = 11) and multi-component (n = 5). We found mixed evidence in the efficacy of music interventions to improve sleep outcomes in older adults, which included sleep quality, objective and subjective sleep characteristics. Music listening interventions contained relaxing music with research teams personalizing music choice based on participants' preferences. Multi-component interventions included listening to music in addition to one other approach, such as massage, tai chi, and nature scenes. Future higher-quality studies should provide a detailed description of music interventions and tailor music selections to older adults' preferences.

Species-specific roles of the Notch ligands, receptors, and targets orchestrating the signaling landscape of the segmentation clock.

Somitogenesis is a hallmark feature of all vertebrates and some invertebrate species that involves the periodic formation of block-like structures called somites. Somites are transient embryonic segments that eventually establish the entire vertebral column. A highly conserved molecular oscillator called the segmentation clock underlies this periodic event and the pace of this clock regulates the pace of somite formation. Although conserved signaling pathways govern the clock in most vertebrates, the mechanisms underlying the species-specific divergence in various clock characteristics remain elusive. For example, the segmentation clock in classical model species such as zebrafish, chick, and mouse embryos tick with a periodicity of ∼30, ∼90, and ∼120 min respectively. This enables them to form the species-specific number of vertebrae during their overall timespan of somitogenesis. Here, we perform a systematic review of the species-specific features of the segmentation clock with a keen focus on mouse embryos. We perform this review using three different perspectives: Notch-responsive clock genes, ligand-receptor dynamics, and synchronization between neighboring oscillators. We further review reports that use non-classical model organisms and in vitro model systems that complement our current understanding of the segmentation clock. Our review highlights the importance of comparative developmental biology to further our understanding of this essential developmental process.

Stiffening Polymer Brush Membranes for Enhanced Organic Solvent Nanofiltration Selectivity.

Membrane-based separations allow energy-efficient purification of organic solvents which are typically carried out by energy-intensive distillation. Polymer membranes are inexpensive and have obtained widespread industrial acceptance for water and biotech applications but not organic solvent nanofiltration due to relatively low selectivities. In this work, a new class of polymer brush membranes was prepared with high selectivities for methanol-toluene separation. Stiffening the brush structure by cross-linking with aromatic trimesic acid and aliphatic itaconic acid resulted in an increase in selectivity from 1.4 to 6.5-11.5. This was achieved by graft polymerization of a primary amine monomer (aminoethyl methacrylate) using single electron transfer-living radical polymerization (SET-LRP) followed by cross-linking. Attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and captive bubble contact angle measurements were used to characterize these membranes. The stiffness of the brush membranes was measured using a quartz crystal microbalance-dissipation (QCM-D) and correlated positively with selectivity for separating organic feed mixtures. This new class of membranes offers a tunable and scalable method for purification of organics.

COVID-19 and its long-term impact on the cardiovascular system.

INTRODUCTION: TheSARS-CoV-2 virus caused a pandemic affecting healthcare deliveryglobally. Despite the presentation of COVID-19 infection beingfrequently dominated by respiratory symptoms; it is now notorious tohave potentially serious cardiovascular sequelae. This articleexplores current data to provide a comprehensive overview of thepathophysiology, cardiovascular risk factors, and implications ofCOVID-19. AREAS COVERED: Inherentstructure of SARS-CoV-2, and its interaction with both ACE-2 andnon-ACE-2 mediated pathways have been implicated in the developmentof cardiovascular manifestations, progressively resulting in acuterespiratory distress syndrome, multiorgan failure, cytokine releasesyndrome, and subsequent myocardial damage. The interplay betweenexisting and de novo cardiac complications must be noted. Forindividuals taking cardiovascular medications, pharmacologicinteractions are a crucial component. Short-term cardiovascularimpacts include arrhythmia, myocarditis, pericarditis, heart failure,and thromboembolism, whereas long-term impacts include diabetes andhypertension. To identify suitable studies, a PubMed literaturesearch was performed including key words such as 'Covid 19,''Cardiovascular disease,' 'Long covid,' etc. EXPERT OPINION: Moresophisticated planning and effective management for cardiologyhealthcare provision is crucial, especially for accommodatingchallenges associated with Long-COVID. With the potential applicationof AI and automated data, there are many avenues and sequelae thatcan be approached for investigation.

Deemed the pandemic of the century, COVID-19 is an illness affecting multiple organ systems. Although the virus is best known for its lung-related complications, its adverse effects on the heart and blood vessels are now becoming more apparent. Rapidly mutating and evolving, its unique structure enables it to undergo interactions with various proteins in the body, resulting in complications of both the heart itself and blood vessels throughout the body. Numerous risk factors have been identified to facilitate these manifestations, including existing heart disease, medication usage, and age. Research has shown that certain drug interactions induce disturbances of the heart rhythm and function. In addition to this, they can also exacerbate preexisting heart-related complications, resulting in severe manifestations. The effects on the heart and blood vessels can be divided into acute and chronic complications. Acute complications include heart failure, rhythm disturbances, heart muscle weakness, and inflammation. In addition to this, chronic complications such as high blood pressure and the new onset of diabetes could also be a consequence. Further research is necessary to improve and enhance both our understanding of the virus and our ability to anticipate heart-related symptoms early on.

Efficient derivation of transgene-free porcine induced pluripotent stem cells enables in vitro modeling of species-specific developmental timing.

Sus scrofa domesticus (pig) has served as a superb large mammalian model for biomedical studies because of its comparable physiology and organ size to humans. The derivation of transgene-free porcine induced pluripotent stem cells (PiPSCs) will, therefore, benefit the development of porcine-specific models for regenerative biology and its medical applications. In the past, this effort has been hampered by a lack of understanding of the signaling milieu that stabilizes the porcine pluripotent state in vitro. Here, we report that transgene-free PiPSCs can be efficiently derived from porcine fibroblasts by episomal vectors along with microRNA-302/367 using optimized protocols tailored for this species. PiPSCs can be differentiated into derivatives representing the primary germ layers in vitro and can form teratomas in immunocompromised mice. Furthermore, the transgene-free PiPSCs preserve intrinsic species-specific developmental timing in culture, known as developmental allochrony. This is demonstrated by establishing a porcine in vitro segmentation clock model that, for the first time, displays a specific periodicity at ∼3.7 h, a timescale recapitulating in vivo porcine somitogenesis. We conclude that the transgene-free PiPSCs can serve as a powerful tool for modeling development and disease and developing transplantation strategies. We also anticipate that they will provide insights into conserved and unique features on the regulations of mammalian pluripotency and developmental timing mechanisms.

Role of inflammation in diabetic cardiomyopathy.

The prevalence of type 2 diabetes (T2D) has reached a pandemic scale. Systemic chronic inflammation dominates the diabetes pathophysiology and has been implicated as a causal factor for the development of vascular complications. Heart failure (HF) is regarded as the most common cardiovascular complication of T2D and the diabetic diagnosis is an independent risk factor for HF development. Key molecular mechanisms pivotal to the development of diabetic cardiomyopathy include the NF-κB pathway and renin-angiotensin-aldosterone system, in addition to advanced glycation end product accumulation and inflammatory interleukin overexpression. Chronic myocardial inflammation in T2D mediates structural and metabolic changes, including cardiomyocyte apoptosis, impaired calcium handling, myocardial hypertrophy and fibrosis, all of which contribute to the diabetic HF phenotype. Advanced cardiovascular magnetic resonance imaging (CMR) has emerged as a gold standard non-invasive tool to delineate myocardial structural and functional changes. This review explores the role of chronic inflammation in diabetic cardiomyopathy and the ability of CMR to identify inflammation-mediated myocardial sequelae, such as oedema and diffuse fibrosis.

Investigation of the Changes in Electronic Properties of Nickel Oxide (NiOx) Due to UV/Ozone Treatment.

Drastic reduction in nickel oxide (NiOx) film resistivity and ionization potential is observed when subjected to ultraviolet (UV)/ozone (O3) treatment. X-ray photoemission spectroscopy suggests that UV/O3 treatment changes the film stoichiometry by introducing Ni vacancy defects. Oxygen-rich NiOx having Ni vacancy defects behaves as a p-type semiconductor. Therefore, in this work, a simple and effective technique to introduce doping in NiOx is shown. Angle-resolved XPS reveals that the effect of UV/O3 treatment does not only alter the film surface property but also introduces oxygen-rich stoichiometry throughout the depth of the film. Finally, simple metal/interlayer/semiconductor (MIS) contacts are fabricated on p-type Si using NiOx as the interlayer and different metals. Significant barrier height reduction is observed with respect to the control sample following UV/O3 treatment, which is in agreement with the observed reduction in film resistivity. From an energy band diagram point of view, the introduction of the UV/O3 treatment changes the defect state distribution, resulting in a change in the pinning of the Fermi level. Therefore, this work also shows that the Fermi level pinning property of NiOx can be controlled using UV/O3 treatment.