Latest Issue
Issue 4 ， 2019
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Advances in low-frequency ultrasound combined with microbubbles in targeted tumor therapy
Abstract：The development of low-frequency ultrasound imaging technology and the improvement of ultrasound contrast agent production technology mean that they play an increasingly important role in tumor therapy. The interaction between ultrasound and microbubbles and their biological effects can transfer and release microbubbles carrying genes and drugs to target tissues, mediate the apoptosis of tumor cells, and block the embolization of tumor microvasculature. With the optimization of ultrasound parameters, the development of targeted microbubbles, and the emergence of various composite probes with both diagnostic and therapeutic functions, low-frequency ultrasound combined with microbubble contrast agents will bring new hope for clinical tumor treatment.Keywords：Low-frequency ultrasound;Microbubble;Gene;Drug;Cell death- 14
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Published：2022-01-05
Review
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Simulation of inter atrial block based on a human atrial model
Abstract：Inter atrial block (IAB) is a prevailing cardiac conduction abnormality that is under-recognized in clinical practice. IAB has strong association with atrial arrhythmia, left atrial enlargement, and electromechanical discordance, increasing the risk of atrial fibrillation (AF) and myocardial ischemia. IAB was generally believed to be caused by impaired conduction along the Bachmann bundle (BB). However, there are three other conduction pathways, including the fibers posteriorly in the vicinity of the right pulmonary veins (VRPV), transseptal fibers in the fossa ovalis (FO), and muscular bundles on the inferior atrial surface near the coronary sinus (CS). We hypothesized that the importance of BB on IAB might have been overestimated. To test this hypothesis, various combinations of conduction pathway blocks were simulated based on a realistic human atrial model to investigate their effects on the index of clinical diagnosis standard of IAB using a simulated 12-lead electrocardiogram (ECG). Firstly, the results showed that the BB block alone could not generate typical P wave morphology of IAB, and that the combination of BB and VRPV pathway block played important roles in the occurrence of IAB. Secondly, although single FO and CS pathways play subordinate roles in inter atrial conduction, their combination with BB and VRPV block could also produce severe IAB. In summary, this simulation study has demonstrated that the combinations of different inter atrial conduction pathways, rather than BB alone, resulted in ECG morphology of IAB. Attention needs to be paid to this in future pathophysiological and clinical studies of IAB.Keywords：Inter atrial block;Electrocardiogram;Simulation;Heart model- 24
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Published：2022-01-05 -
Mitochondrial superoxide anions induced by exogenous oxidative stress determine tumor cell fate: an individual cell-based study
Abstract：Objective:Reactive oxygen species (ROS) are involved in a variety of biological phenomena and serve both deleterious and beneficial roles. ROS quantification and assessment of reaction networks are desirable but difficult because of their short half-life and high reactivity. Here, we describe a pro-oxidative model in a single human lung carcinoma SPC-A-1 cell that was created by application of extracellular H2O2 stimuli.Methods:Modified microfluidics and imaging techniques were used to determine O2•− levels and construct an O2•− reaction network. To elucidate the consequences of increased O2•− input, the mitochondria were given a central role in the oxidative stress mode, by manipulating mitochondria-interrelated cytosolic Ca2+ levels, mitochondrial Ca2+ uptake, auto-amplification of intracellular ROS and the intrinsic apoptotic pathway.Results and conclusions:Results from a modified microchip demonstrated that 1 mmol/L H2O2 induced a rapid increase in cellular O2•− levels (>27 vs. >406 amol in 20 min), leading to increased cellular oxidizing power (evaluated by ROS levels) and decreased reducing power (evaluated by glutathione (GSH) levels). In addition, we examined the dynamics of cytosolic Ca2+ and mitochondrial Ca2+ by confocal laser scanning microscopy and confirmed that Ca2+ stores in the endoplasmic reticulum were the primary source of H2O2-induced cytosolic Ca2+ bursts. It is clear that mitochondria have pivotal roles in determining how exogenous oxidative stress affects cell fate. The stress response involves the transfer of Ca2+ signals between organelles, ROS auto-amplification, mitochondrial dysfunction, and a caspase-dependent apoptotic pathway.Keywords：Individual cell;Superoxide anion;Reactive oxygen species (ROS) dynamics;Intrinsic apoptotic pathway;Ca2+ signaling- 130
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Published：2022-01-05 -
Regulation of flowering time via miR172-mediated
APETALA2-like expression in ornamental gloxinia (Sinningia speciosa )#Abstract：We investigated the microRNA172 (miR172)-mediated regulatory network for the perception of changes in external and endogenous signals to identify a universally applicable floral regulation system in ornamental plants, manipulation of which could be economically beneficial. Transgenic gloxinia plants, in which miR172 was either overexpressed or suppressed, were generated using Agrobacterium-mediated transformation. They were used to study the effect of altering the expression of this miRNA on time of flowering and to identify its mRNA target. Early or late flowering was observed in transgenic plants in which miR172 was overexpressed or suppressed, respectively. A full-length complementary DNA (cDNA) of gloxinia (Sinningia speciosa) APETALA2-like (SsAP2-like) was identified as a target of miR172. The altered expression levels of miR172 caused up-or down-regulation of SsAP2-like during flower development, which affected the time of flowering. Quantitative real-time reverse transcription PCR analysis of different gloxinia tissues revealed that the accumulation of SsAP2-like was negatively correlated with the expression of miR172a, whereas the expression pattern of miR172a was negatively correlated with that of miR156a. Our results suggest that transgenic manipulation of miR172 could be used as a universal strategy for regulating time of flowering in ornamental plants.Keywords：Flowering time;Transgenic gloxinia;MicroRNA172;APETALA2-like (AP2-like)- 24
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Published：2022-01-05 -
Screening, purification, and characterization of an extracellular lipase from
Aureobasidium pullulans isolated from stuffed buns steamersAbstract：An extracellular lipase from Aureobasidium pullulans was obtained and purified with a specific activity of 17.7 U/mg of protein using ultrafiltration and a DEAE-Sepharose Fast Flow column. Characterization of the lipase indicated that it is a novel finding from the species A. pullulans. The molecular weight of the lipase was 39.5 kDa, determined by sodium dodecyl sulfonate-polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme exhibited its optimum activity at 40 °C and pH of 7. It also showed a remarkable stability in some organic solutions (30%, v/v) including n-propanol, isopropanol, dimethyl sulfoxide (DMSO), and hexane. The catalytic activity of the lipase was enhanced by Ca2+ and was slightly inhibited by Mn2+ and Zn2+ at a concentration of 10 mmol/L. The lipase was activated by the anionic surfactant SDS and the non-ionic surfactants Tween 20, Tween 80, and Triton X-100, but it was drastically inhibited by the cationic surfactant cetyl trimethyl ammonium bromide (CTAB). Furthermore, the lipase was able to hydrolyze a wide variety of edible oils, such as peanut oil, corn oil, sunflower seed oil, sesame oil, and olive oil. Our study indicated that the lipase we obtained is a potential biocatalyst for industrial use.Keywords：Lipase;Aureobasidium pullulans;Purification;Enzymatic characterization- 104
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Published：2022-01-05 -
Development of a colloidal gold-based immunochromatographic strip for rapid detection of
Rice stripe virus Abstract：Rice stripe virus (RSV) causes dramatic losses in rice production worldwide. In this study, two monoclonal antibodies (MAbs) 16E6 and 11C1 against RSV and a colloidal gold-based immunochromatographic strip were developed for specific, sensitive, and rapid detection of RSV in rice plant and planthopper samples. The MAb 16E6 was conjugated with colloidal gold and the MAb 11C1 was coated on the test line of the nitrocellulose membrane of the test strip. The specificity of the test strip was confirmed by a positive reaction to RSV-infected rice plants and small brown planthopper (SBPH), and negative reactions to five other rice viruses, healthy rice plants, four other vectors of five rice viruses, and non-viruliferous SBPH. Sensitivity analyses showed that the test strip could detect the virus in RSV-infected rice plant tissue crude extracts diluted to 1:20 480 (w/v, g/mL), and in individual viruliferous SBPH homogenate diluted to 1:2560 (individual SPBH/μL). The validity of the developed strip was further confirmed by tests using field-collected rice and SBPH samples. This newly developed test strip is a low-cost, fast, and easy-to-use tool for on-site detection of RSV infection during field epidemiological studies and paddy field surveys, and thus can benefit decision-making for RSV management in the field.Keywords：Monoclonal antibody;Colloidal gold-based immunochromatographic strip;Rice stripe virus;Rice;Small brown planthopper- 93
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Published：2022-01-05 -
Dexamethasone protects the glycocalyx on the kidney microvascular endothelium during severe acute pancreatitis
Abstract：Objective:This study demonstrated that dexamethasone (DEX) protects the endothelial glycocalyx from damage induced by the inflammatory stimulus tumor necrosis factor-α (TNF-α) during severe acute pancreatitis (SAP), and improves the renal microcirculation.Methods:Ninety mice were evenly divided into 3 groups (Sham, SAP, and SAP+DEX). The SAP mice model was established by ligature of pancreatic duct and intraperitoneal injection of cerulein. Renal perfusion and function, and morphological changes of the glycocalyx were evaluated by laser Doppler velocimetry, electron microscopy, and histopathology (hematoxylin and eosin (H&E) staining), respectively. Serum levels of syndecan-1 and TNF-α were assessed by enzyme-linked immunosorbent assay (ELISA). The protective effects of dexamethasone on the glycocalyx and renal microcirculation were evaluated.Results:Significantly high levels of serum TNF-α were detected 3 h after the onset of SAP. These levels might induce degradation of the glycocalyx and kidney hypoperfusion, resulting in kidney microcirculation dysfunction. The application of dexamethasone reduced the degradation of the glycocalyx and improved perfusion of kidney.Conclusions:Dexamethasone protects the endothelial glycocalyx from inflammatory degradation possibly initiated by TNF-α during SAP. This is might be a significant discovery that helps to prevent tissue edema and hypoperfusion in the future.Keywords：Severe acute pancreatitis (SAP);Acute kidney injury (AKI);Glycocalyx;Dexamethasone;Tumor necrosis factor-α(TNF-α)- 35
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Published：2022-01-05 -
Incidence and clinical correlates of anger attacks in Chinese patients with obsessive-compulsive disorder
Abstract：Objective:Anger attacks have been observed in patients with obsessive-compulsive disorder (OCD), often triggered by obsessional triggers. However, few studies have reported the clinical characteristics and correlates of anger attacks among Chinese patients with OCD.Methods:A total of 90 adults with a primary diagnosis of OCD, ranging from 15 to 78 years old, participated in the study. Participants were administered the Rage Outbursts and Anger Rating Scale (ROARS), Yale-Brown Obsessive-Compulsive Scale-Second Edition, and Brown Assessment of Beliefs Scale by a trained clinician. Patients completed the Obsessive-Compulsive Inventory-Revised and Depression Anxiety Stress Scale-21.Results:A total of 31.3% of participants reported anger outbursts in the past week, and ROARS scores had no significant correlation with age, duration of illness, OCD severity, depression, or stress. However, ROARS scores were negatively related to education level, and positively related to obsessing symptoms and anxiety.Conclusions:These data suggest that anger attacks are relatively common in Chinese patients with OCD. The severity of anger attacks is related to educational level, obsessing symptoms, and anxiety, which may be a latent variable reflecting executive functioning and emotion regulation skills.Keywords：Obsessive-compulsive disorder;Anger attacks;Assessment;China- 126
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Published：2022-01-05
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