Purpose
To assess the management and safety of epidural or general anesthesia for Cesarean delivery in parturients with coronavirus disease (COVID-19) and their newborns, and to evaluate the ...standardized procedures for protecting medical staff.
Methods
We retrospectively reviewed the cases of parturients diagnosed with severe acute respiratory syndrome coronavirus (SARS-CoV-2) infection disease (COVID-19). Their epidemiologic history, chest computed tomography scans, laboratory measurements, and SARS-CoV-2 nucleic acid positivity were evaluated. We also recorded the patients’ demographic and clinical characteristics, anesthesia and surgery-related data, maternal and neonatal complications, as well as the health status of the involved medical staff.
Results
The clinical characteristics of 17 pregnant women infected with SARS-CoV-2 were similar to those previously reported in non-pregnant adult patients. All of the 17 patients underwent Cesarean delivery with anesthesia performed according to standardized anesthesia/surgery procedures. Fourteen of the patients underwent continuous epidural anesthesia with 12 experiencing significant intraoperative hypotension. Three patients received general anesthesia with tracheal intubation because emergency surgery was needed. Three of the parturients are still recovering from their Cesarean delivery and are receiving in-hospital treatment for COVID-19. Three neonates were born prematurely. There were no deaths or serious neonatal asphyxia events. All neonatal SARS-CoV-2 nucleic acid tests were negative. No medical staff were infected throughout the patient care period.
Conclusions
Both epidural and general anesthesia were safely used for Cesarean delivery in the parturients with COVID-19. Nevertheless, the incidence of hypotension during epidural anesthesia appeared excessive. Proper patient transfer, medical staff access procedures, and effective biosafety precautions are important to protect medical staff from COVID-19.
Segmentation of pneumonia lesions from CT scans of COVID-19 patients is important for accurate diagnosis and follow-up. Deep learning has a potential to automate this task but requires a large set of ...high-quality annotations that are difficult to collect. Learning from noisy training labels that are easier to obtain has a potential to alleviate this problem. To this end, we propose a novel noise-robust framework to learn from noisy labels for the segmentation task. We first introduce a noise-robust Dice loss that is a generalization of Dice loss for segmentation and Mean Absolute Error (MAE) loss for robustness against noise, then propose a novel COVID-19 Pneumonia Lesion segmentation network (COPLE-Net) to better deal with the lesions with various scales and appearances. The noise-robust Dice loss and COPLE-Net are combined with an adaptive self-ensembling framework for training, where an Exponential Moving Average (EMA) of a student model is used as a teacher model that is adaptively updated by suppressing the contribution of the student to EMA when the student has a large training loss. The student model is also adaptive by learning from the teacher only when the teacher outperforms the student. Experimental results showed that: (1) our noise-robust Dice loss outperforms existing noise-robust loss functions, (2) the proposed COPLE-Net achieves higher performance than state-of-the-art image segmentation networks, and (3) our framework with adaptive self-ensembling significantly outperforms a standard training process and surpasses other noise-robust training approaches in the scenario of learning from noisy labels for COVID-19 pneumonia lesion segmentation.
The homeostatic link between oxidative stress and autophagy plays an important role in cellular responses to a wide variety of physiological and pathological conditions. However, the regulatory ...pathway and outcomes remain incompletely understood. Here, we show that reactive oxygen species (ROS) function as signaling molecules that regulate autophagy through ataxia‐telangiectasia mutated (ATM) and cell cycle checkpoint kinase 2 (CHK2), a DNA damage response (DDR) pathway activated during metabolic and hypoxic stress. We report that CHK2 binds to and phosphorylates Beclin 1 at Ser90/Ser93, thereby impairing Beclin 1‐Bcl‐2 autophagy‐regulatory complex formation in a ROS‐dependent fashion. We further demonstrate that CHK2‐mediated autophagy has an unexpected role in reducing ROS levels via the removal of damaged mitochondria, which is required for cell survival under stress conditions. Finally, CHK2−/− mice display aggravated infarct phenotypes and reduced Beclin 1 p‐Ser90/Ser93 in a cerebral stroke model, suggesting an in vivo role of CHK2‐induced autophagy in cell survival. Taken together, these results indicate that the ROS‐ATM‐CHK2‐Beclin 1‐autophagy axis serves as a physiological adaptation pathway that protects cells exposed to pathological conditions from stress‐induced tissue damage.
Synopsis
Whether hypoxia and nutrient starvation are coupled to cellular autophagy remains unclear. Here, DNA damage response kinases ATM and CHK2 are shown to trigger autophagy in response to reactive oxygen species (ROS) accumulation, suggesting a novel physiological adaptation pathway toward metabolic stress.
Depletion of CHK2 or ATM impairs oxidative stress‐induced autophagy in MEFs.
CHK2 binds and phosphorylates Beclin1 at Ser90/Ser93, suppressing Beclin1‐Bcl‐2 autophagy regulatory complex formation.
CHK2‐induced autophagy limits intracellular ROS levels by clearing damaged mitochondria.
CHK2‐induced autophagy protects against cell death and tissue damage following cerebral ischemia.
ROS accumulation activates protective autophagy to prevent stress‐induced tissue damage.
In a screen for ribavirin resistance, a novel high-fidelity variant of human enterovirus 71 (EV71) with the single amino acid change L123F in its RNA-dependent RNA polymerase (RdRp or 3D) was ...identified. Based on the crystal structure of EV71 RdRp, L123 locates at the entrance of the RNA template binding channel, which might form a fidelity checkpoint. EV71 RdRp-L123F variants generated less progeny in a guanidine resistance assay and virus populations with lower mutation frequencies in cell culture passage due to their higher replication fidelity. However, compared with wild-type viruses, they did not show growth defects. In vivo infections further revealed that high-fidelity mutations L123F and G64R (previously reported) negatively impacted EV71 fitness and greatly reduced viral pathogenicity alone or together in AG129 mice. Interestingly, a variant with double mutations, RG/B4-G64R/L123F (where RG/B4 is an EV71 genotype B4 virus constructed by reverse genetics RG)showed higher fidelity in vitro and less virulence in vivo than any one of the above two single mutants. The 50% lethal dose (LD50) of the double mutant increased more than 500 times compared with the LD50 of wild-type RG/B4 in mice. The results indicated that these high-fidelity variants exhibited an attenuated pathogenic phenotype in vivo and offer promise as a live attenuated EV71 vaccine.
The error-prone nature of the RNA-dependent RNA polymerase (RdRp) of RNA viruses during replication results in quasispecies and aids survival of virus populations under a wide range of selective pressures. Virus variants with higher replication fidelity exhibit lower genetic diversity and attenuated pathogenicity in vivo. Here, we identified a novel high-fidelity mutation L123F in the RdRp of human enterovirus 71 (EV71). We further elucidated that EV71 variants with the RdRp-L123F mutation and/or the previously identified high-fidelity mutation RdRp-G64R were attenuated in an AG129 mouse model. As EV71 has emerged as a serious worldwide health threat, especially in developing countries in the Asia-Pacific region, we urgently need EV71 vaccines. Learning from the poliovirus vaccination, we prefer live attenuated EV71 vaccines to inactivated EV71 vaccines in order to effectively control EV71 outbreaks at low cost. Our results imply a new means of attenuating EV71 and reducing its mutation rate at the same time.
This brief investigates the predefined-time bipartite consensus of multiple Euler-Lagrange systems with a dynamic leader. A new distributed predefined-time observer is added to estimate the desired ...velocity of each follower. Then, a new sliding surface and a distributed protocol are constructed to guarantee the networked systems achieve the bipartite consensus within a predefined time. It should be pointed out that, all the observing time, sliding time and reaching time can be preset in advance according to the task requirements. One numerical example with two-link robot arms is proposed to verify the effectiveness of the new designs.
The 2018 Global Innovation Index ranks Pakistan 118 out of 126 in innovation. One of the main reasons why developing countries, such as Pakistan, fail to innovate is their improvisation of astute and ...concurrent knowledge. This study explores the contemporary hurdles that lead to manufacturing firms' low agility and innovation performance. Based on the theory of dynamic capability view and the theory of absorptive capacity, we propose that the knowledge absorption capacity of firms can help them organize or utilize dynamic capabilities, such as big data analytics and digital platform capability, to enhance their agility and innovation performance. However, in the presence of a diversified organizational culture (i.e., flexibility orientations and data-driven culture), the desired outcomes may be affected. For this purpose, this study performed a questionnaire survey to collect data for validating the theoretical model. The collected responses from 325 manufacturing firms were analyzed using structural equation modeling, and empirical results reveal a positive relationship between the knowledge absorption capacity, agility, and innovation performance of firms mediated by big data analytics and DP capabilities. Flexibility orientations also showed a significant moderating role, but the role of data-driven culture was not significant. Statistical results reject the hypothesis. This study enriches the scope of the theories mentioned above and comes up with several other interesting theoretical and managerial implications valuable for academicians and policymakers.
Accumulating evidence has highlighted the importance of microglial and astrocyte responses in the pathological development of postoperative cognitive dysfunction (POCD). However, the mechanisms ...involved are not well understood.
A perioperative neurocognitive disorders (PND) mouse model was generated by administering etomidate, and cognitive function was assessed using the Morris water maze and novel object recognition tests. Excitatory and inhibitory postsynaptic currents were recorded to analyze neuronal activity. In addition, microglia and astrocytes were isolated by magnetic-activated cell sorting, and genes that were activated in these cells were identified using quantitative polymerase chain reaction.
We observed dramatic cognitive impairment at 1 and 3 weeks after etomidate was administered to 18 month-old mice. Microglia and astrocytes isolated from the hippocampus showed significant microglial activation during the early pathological stage (i.e., 1 week after etomidate injection) and an A1-specific astrocyte response during the late pathological stage (i.e., 3 weeks after etomidate injection). Furthermore, when microglia were eliminated before etomidate was injected, the A1-specific astrocyte activation response was significantly reduced, and cognitive function improved. However, when microglia were eliminated after etomidate application, astrocyte activation and cognitive function were not significantly altered. In addition, activating microglia immediately after a sedative dose of etomidate was injected markedly increased A1-specific astrocyte activation and cognitive dysfunction.
A1-specific astrocyte activation is triggered by activated microglia during the initial pathological stage of PND and induces long-term synaptic inhibition and cognitive deficiencies. These results improve our understanding of how PND develops and may suggest therapeutic targets.
Tea, as one kind of worldwide popular drink, has complicated aroma profiles. In normal drinking experience, temperatures and matrices affect our perception of tea aroma. In addition, ultrasonic ...nebulization extraction (UNE), is also viewed as a special way to release tea aroma. In this paper, to investigate the effects of UNE, temperatures, and matrices on the aroma release and profiles expression of Lu'an Guapian tea, solid-phase microextraction–gas chromatography–mass spectrometry (SPME–GC–MS) and descriptive sensory analysis (DSA) were used. The results showed that the aroma profiles showed significantly difference in different temperatures and matrices. Especially, UNE could efficiently express detailed aroma profiles at low temperature (20 °C), which may be used in the tea aroma evaluation in the future.
•SPME–GC–MS and DSA was used to analysis green tea volatiles.•Multivariate analyses (PCA & PLS) were used to visualize data.•Green tea aroma profiles were easily affected by different temperatures and matrices.•UNE could efficiently express green tea aroma profile at low temperature.
The dynamical system with a second-order+first-order structure has been proven to be effective for solving convex optimization problems with equality constraints. In this paper, this structure is ...extended to distributed optimization to deal with set-constrained convex optimization problems under strongly connected and weight-balanced directed topology, and a continuous optimization dynamics based on projection operator and primal-dual method is proposed. When proper values of the system parameters are selected, the dynamics converges quickly to the optimal solution of the problem. Finally, two numerical experiments are given to verify the effectiveness of the proposed model.
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