Hemodynamic performance evaluation of neonatal ECMO double lumen cannula using fluid-structure interaction.

Extra corporeal membrane oxygenation (ECMO) is an artificial oxygenation facility, employed in situations of cardio-pulmonary failure. Some diseases i.e., acute respiratory distress syndrome, pulmonary hypertension, corona virus disease (COVID-19) etc. affect oxygenation performance of the lungs thus requiring the need of artificial oxygenation. Critical care teams used ECMO technique during the COVID-19 pandemic to support the heart and lungs of COVID-19 patients who had an acute respiratory or cardiac failure. Double Lumen Cannula (DLC) is one of the most critical components of ECMO as it resides inside the patient and, connects patient with external oxygenation circuit. DLC facilitates delivery and drainage of blood from the patient's body. DLC is characterized by delicate balance of internal and external flows inside a limited space of the right atrium (RA). An optimal performance of the DLC necessitates structural stability under biological and hemodynamic loads, a fact that has been overlooked by previously published studies. In the past, many researchers experimentally and computationally investigated the hemodynamic performance of DLC by employing Eulerian approach, which evaluate instantaneous blood damage without considering blood shear exposure history (qualitative assessment only). The present study is an attempt to address the aforementioned limitations of the previous studies by employing Lagrangian (quantitative assessment) and incorporating the effect of fluid-structure interaction (FSI) to study the hemodynamic performance of neonatal DLC. The study was performed by solving three-dimensional continuity, momentum, and structural mechanics equation(s) by numerical methods for the blood flow through neonatal DLC. A two-way coupled FSI analysis was performed to analyze the effect of DLC structural deformation on its hemodynamic performance. Results show that the return lumen was the most critical section with maximum pressure drop, velocity, shear stresses, and blood damage. Recirculation and residence time of blood in the right atrium (RA) increases with increasing blood flow rates. Considering the structural deformation has led to higher blood damage inside the DLC-atrium system. Maximum Von-Mises stress was present on the side edges of the return lumen that showed direct proportionality with the blood flow rate.

The Mediating Effect of Self-Efficacy and Coping Strategy in Relation to Job Stress and Psychological Well-Being of Home-Visiting Care Workers for Elderly during the COVID-19 Pandemic.

The purpose of this study was to analyze the mediating effect of self-efficacy and coping strategy in the relationship between job stress and the psychological well-being of care workers. The subjects were 112 home-visiting care workers, and data were collected at four home-visiting nursing centers in a metropolitan city and a small and medium-sized city from July to August 2022. The collected data were analyzed by descriptive statistics, t-test, ANOVA, Pearson's correlation co-efficient, multiple linear regression, and Sobel test. The mean score of psychological well-being was 3.33 ± 0.46 out of a possible 5. The subject's psychological well-being was correlated with self-efficacy (r = 0.64, p < 0.001), problem-solving-focused coping (r = 0.58, p < 0.001), social-support-seeking coping (r = 0.34, p < 0.001), job stress (r = -0.31, p = 0.001), avoidance-focused coping (r = -0.37, p < 0.001). Self-efficacy (Z = -4.92, p < 0.001), problem-solving-focused coping (Z = -2.56, p = 0.010), and avoidance-focused coping (Z = -3.07, p = 0.002) had a mediating effect in the relationship between job stress and psychological well-being of the subjects during the COVID-19 pandemic. Based on these results, the psychological well-being nursing intervention program for home-visiting care workers need to include job stress, problem-solving-focused coping, and avoidance-focused coping.

A chemical tool for blue light-inducible proximity photo-crosslinking in live cells† † Electronic supplementary information (ESI) available. see DOI: 10.1039/d1sc04871f

We developed a proximity photo-crosslinking method (Spotlight) with a 4-azido-N-ethyl-1,8-naphthalimide (AzNP) moiety that can be converted to reactive aryl nitrene species using ambient blue light-emitting diode light. Using an AzNP-conjugated HaloTag ligand (VL1), blue light-induced photo-crosslinked products of various HaloTag-conjugated proteins of interest were detected in subcellular spaces in live cells. Chemical or heat stress-induced dynamic changes in the proteome were also detected, and photo-crosslinking in the mouse brain tissue was enabled. Using Spotlight, we further identified the host interactome of SARS-CoV-2 nucleocapsid (N) protein, which is essential for viral genome assembly. Mass analysis of the VL1-crosslinked product of N-HaloTag in HEK293T cells showed that RNA-binding proteins in stress granules were exclusively enriched in the cross-linked samples. These results tell that our method can reveal the interactome of protein of interest within a short distance in live cells. We developed a spatiotemporal proximity photo-crosslinking by visible light activation (Spotlight) method to capture protein–protein interactions in live systems.

A chemical tool for blue light-inducible proximity photo-crosslinking in live cells.

We developed a proximity photo-crosslinking method (Spotlight) with a 4-azido-N-ethyl-1,8-naphthalimide (AzNP) moiety that can be converted to reactive aryl nitrene species using ambient blue light-emitting diode light. Using an AzNP-conjugated HaloTag ligand (VL1), blue light-induced photo-crosslinked products of various HaloTag-conjugated proteins of interest were detected in subcellular spaces in live cells. Chemical or heat stress-induced dynamic changes in the proteome were also detected, and photo-crosslinking in the mouse brain tissue was enabled. Using Spotlight, we further identified the host interactome of SARS-CoV-2 nucleocapsid (N) protein, which is essential for viral genome assembly. Mass analysis of the VL1-crosslinked product of N-HaloTag in HEK293T cells showed that RNA-binding proteins in stress granules were exclusively enriched in the cross-linked samples. These results tell that our method can reveal the interactome of protein of interest within a short distance in live cells.