Risk Factors for Ventilator Dependency Following Coronary Artery Bypass Grafting

Background: Ventilator dependency following coronary artery bypass grafting (CABG) is often associated with significant morbidity and mortality. However, few reports have focused on the independent risk factors for ventilator dependency following CABG. This study aimed to evaluate the independent risk factors for ventilator dependency following coronary artery bypass grafting (CABG). Methods: The relevant pre-, intra- and post-operative data of patients without a history of chronic obstructive pulmonary disease undergoing isolated CABG from January 2003 to December 2008 in our center were retrospectively analyzed. Elapsed time between CABG and extubation of more than 48 hours was defined as postoperative ventilator dependency (PVD). Results: The incidence of PVD was 13.8% (81/588). The in-hospital mortality in the PVD group was significantly higher than that in the non-PVD group (8.6% versus 2.4%, p=0.0092). Besides the length of ICU and hospital stay, PVD correlated with negative respiratory outcomes. The independent risk factors for PVD were preoperative congestive heart failure (OR=2.456, 95%CI 1.426-6.879), preoperative hypoalbuminemia (OR=1.353, 95%CI 1.125-3.232), preoperative arterial oxygen partial pressure (PO2) (OR=0.462, 95%CI 0.235-0.783) and postoperative anaemia (OR=1.541, 95%CI 1.231-3.783). Conclusions: Preoperative congestive heart failure, preoperative hypoalbuminemia, low preoperative PO2 and postoperative anaemia were identified as four independent risk factors for ventilator dependency following CABG

Evaluation of stroke topographic patterns and intracerebral hemodynamics in unilateral internal carotid artery stenosis or occlusion

Objective To study the pathogenesis of cerebrovascular disorders by analysing the categories of cerebral infarct on magnetic resonance imaging (MRI) and intracerebral hemodynamics of patients with unilateral atherosclerotic internal carotid artery stenosis or occlusion (ICASO). Methods From August 2007 to May 2009, 87 ischemic stroke patients who were diagnosed arteriosclerosis ICASO by cerebral arteriography were investigated in Department of Neurology, the First Teaching Hospital of Xinjiang Medical University. Patients with potential cardiac sources of embolism were excluded. Cerebral infarct patterns were detected by MRI and the difference in cerebral hemodynamics were analysed by transcranial Doppler (TCD) among different imaging patterns. Results The infarct patterns in 87 patients were divided into 4 groups: territory infarcts (n = 30, 34.48%), subcortical infarcts (n = 27, 31.03%), border⁃ zone infarcts (n = 18, 20.69%), and disseminated small infarcts (n = 12, 13.79%). The distribution ratio of topographic patterns was significant in different degree of ICASO (χ2 = 7.156, P = 0.028). The topographic pattern was negatively correlated with the degree of ICASO (r = ⁃ 0.275, P = 0.010). Serious internal carotid artery (ICA) stenosis was associated with subcortical infarcts, border⁃zone infarcts (11/36, 30.56%, for all); territory infarcts showed a strong trend to appear mostly in patients with total ICA occulation (17/34, 50.00%). Seventy⁃five cases were involved in the hemodynamics analysis. In different groups of patient the mean flow velocity (Vm) and blood vessel pulsatility index (PI) of the affected side were all significantly lower than those of the intact side, while the lowest was shown in territory infarcts, and then in border⁃zone infarcts (P = 0.000, for all). Conclusion ICASO is mostly seen in patients with territory infarct, and hemodynamic disorder may occur in all infarct patterns. Therefore, cerebral infarct patterns and hemodynamic changes should be adequately considered for selecting optimal therapeutic and preventive measures. DOI：10.3969/j.issn.1672-6731.2011.03.01

Stem Cell Derived Phenotypic Human Neuromuscular Junction Model For Dose Response Evaluation Of Therapeutics

There are currently no functional neuromuscular junction (hNMJ) systems composed of human cells that could be used for drug evaluations or toxicity testing in vitro. These systems are needed to evaluate NMJs for diseases such as amyotrophic lateral sclerosis, spinal muscular atrophy or other neurodegenerative diseases or injury states. There are certainly no model systems, animal or human, that allows for isolated treatment of motoneurons or muscle capable of generating dose response curves to evaluate pharmacological activity of these highly specialized functional units. A system was developed in which human myotubes and motoneurons derived from stem cells were cultured in a serum-free medium in a BioMEMS construct. The system is composed of two chambers linked by microtunnels to enable axonal outgrowth to the muscle chamber that allows separate stimulation of each component and physiological NMJ function and MN stimulated tetanus. The muscle\u27s contractions, induced by motoneuron activation or direct electrical stimulation, were monitored by image subtraction video recording for both frequency and amplitude. Bungarotoxin, BOTOX® and curare dose response curves were generated to demonstrate pharmacological relevance of the phenotypic screening device. This quantifiable functional hNMJ system establishes a platform for generating patient-specific NMJ models by including patient-derived iPSCs

Challenges and advancements for AR optical see-through near-eye displays: a review

Optical see-through near-eye display (NED) technologies for augmented reality (AR) have achieved significant advancements recently with investments from both academia and industry. Although various AR NED products have been successfully commercialized and even deployed into applications, there are still challenges with present AR NED technologies (e.g., limited eyebox, fixed focus, bulky form factors). In this review, we present a brief overview of leading AR NED technologies and then focus on the state-of-the-art research works to counter the respective key challenges with each of the leading AR NED technologies. We also introduce a number of emerging technologies that are worthy of close study.Published versionThis work is supported by the National Natural Science Foundation of China (Grant No. 62005154), the Natural Science Foundation of Shanghai (Grant No. 20ZR1420500), National Key Research and Development Program of China (No. 2021YFF0307803) and MOE TIF Grant (MOE2019-TIF0011)

Repurposed Biological Scaffolds: Kidney To Pancreas

Advances in organ regeneration have been facilitated by gentle decellularization protocols that maintain distinct tissue compartments, and thereby allow seeding of blood vessels with endothelial lineages separate from populations of the parenchyma with tissue-specific cells. We hypothesized that a reconstituted vasculature could serve as a novel platform for perfusing cells derived from a different organ: thus discordance of origin between the vascular and functional cells, leading to a hybrid repurposed organ. The need for a highly vascular bed is highlighted by tissue engineering approaches that involve transplantation of just cells, as attempted for insulin production to treat human diabetes. Those pancreatic islet cells present unique challenges since large numbers are needed to allow the cell-to-cell signaling required for viability and proper function; however, increasing their number is limited by inadequate perfusion and hypoxia. As proof of principle of the repurposed organ methodology we harnessed the vasculature of a kidney scaffold while seeding the collecting system with insulin-producing cells. Pig kidneys were decellularized by sequential detergent, enzymatic and rinsing steps. Maintenance of distinct vascular and collecting system compartments was demonstrated by both fluorescent 10 micron polystyrene microspheres and cell distributions in tissue sections. Sterilized acellular scaffolds underwent seeding separately via the artery (fibroblasts or endothelioma cells) and retrograde (murine bTC-tet cells) up the ureter. After three-day bioreactor incubation, histology confirmed separation of cells in the vasculature from those in the collecting system. βTC-tet clusters survived in tubules, glomerular Bowman’s space, demonstrated insulin immunolabeling, and thereby supported the feasibility of kidney-to-pancreas repurposing