Adolescent ; Adult ; Female ; Hearing Loss, Sudden ; etiology ; psychology ; Humans ; Male ; Middle Aged ; Young Adult

Toad venom is the Bufo bufo gargarizans or B. melanostictus after the ears of the gland secretion, used in the treatment of various cancers in recent years. Research shows that the main anti-tumor components in bufadienolide. Bufadienolide have free type structure and conjunct type structure. To identify and clarify the difference between bufogenin and bufotoxin contained in Bufonis Venenum, which was from B. bufo gargarizans, an UPLC-TQ-MS method has been established. UPLC-TQ-MS method was used to identify and quantify the major bufadienolides in Bufonis Venenum. UPLC-TQ-MS assay with positive ion mode was performed on a Waters ACQUITY UPLC BEH C, (2.1 mm x 100 mm, 1.7 µm) with the mobile phase consisting of 0. 1% aqueous formic and acidacetonitrile in gradient elution at a flow rate of 0.4 mL · min⁻¹ and the column temperature was set at 35 °C. By comparing their retention time and high resolution mass data of Bufonis Venenum extracts, 37 effective components were primarily identified by MS/MS analysis in positive ion mode. Twenty-six of them were free-type bufadienolides (bufogenin), 11 of them were conjugated bufadienolides. There were significant differences in the main composition between fresh and processed Bufonis Venenum. The study found that the chemical composition of toad venom through great changes after processing, conjunct type content is much less, free type content as well change.
Amphibian Venoms ; chemistry ; metabolism ; Animals ; Bufonidae ; classification ; metabolism ; Chromatography, High Pressure Liquid ; methods ; Molecular Structure ; Tandem Mass Spectrometry ; methods

Genome sequencing projects revealed massive cryptic gene clusters encoding the undiscovered secondary metabolites in Streptomyces. To investigate the metabolic products of silent gene clusters in Streptomyces chattanoogensis L10 (CGMCC 2644), we used site-directed mutagenesis to generate ten mutants with point mutations in the highly conserved region of rpsL (encoding the ribosomal protein S12) or rpoB (encoding the RNA polymerase β-subunit). Among them, L10/RpoB (H437Y) accumulated a dark pigment on a yeast extract-malt extract-glucose (YMG) plate. This was absent in the wild type. After further investigation, a novel angucycline antibiotic named anthrachamycin was isolated and determined using nuclear magnetic resonance (NMR) spectroscopic techniques. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis and electrophoretic mobility shift assay (EMSA) were performed to investigate the mechanism underlying the activation effect on the anthrachamycin biosynthetic gene cluster. This work indicated that the rpoB-specific missense H437Y mutation had activated anthrachamycin biosynthesis in S. chattanoogensis L10. This may be helpful in the investigation of the pleiotropic regulation system in Streptomyces.

BACKGROUND:Partial pressure of end-tidal carbon dioxide (PETCO2) has been used to monitor the effectiveness of precordial compression (PC) and regarded as a prognostic value of outcomes in cardiopulmonary resuscitation (CPR). This study was to investigate changes of PETCO2 during CPR in rats with ventricular fibrillation (VF) versus asphyxial cardiac arrest. METHODS:Sixty-two male Sprague-Dawley (SD) rats were randomly divided into an asphyxial group (n=32) and a VF group (n=30). PETCO2 was measured during CPR from a 6-minute period of VF or asphyxial cardiac arrest. RESULTS:The initial values of PETCO2 immediately after PC in the VF group were significantly lower than those in the asphyxial group (12.8±4.87 mmHg vs. 49.2±8.13 mmHg,P=0.000). In the VF group, the values of PETCO2 after 6 minutes of PC were significantly higher in rats with return of spontaneous circulation (ROSC), compared with those in rats without ROSC (16.5±3.07 mmHg vs. 13.2±2.62 mmHg,P=0.004). In the asphyxial group, the values of PETCO2 after 2 minutes of PC in rats with ROSC were significantly higher than those in rats without ROSC (20.8±3.24 mmHg vs. 13.9±1.50 mmHg,P=0.000). Receiver operator characteristic (ROC) curves of PETCO2 showed significant sensitivity and specificity for predicting ROSC in VF versus asphyxial cardiac arrest. CONCLUSIONS:The initial values of PETCO2 immediately after CPR may be helpful in differentiating the causes of cardiac arrest. Changes of PETCO2 during CPR can predict outcomes of CPR.

This experiment was expected to test whether nitric oxide (NO) exerted significant effect on the central respiratory rhythm. Experiments were performed on in vitro brainstem slice preparations from neonatal rats. These preparations include the medial region of the nucleus retrofacialis (mNRF); a part of pre-Bötinger complex, ventral respiratory group (VRG) and dorsal respiratory group (DRG). Respiratory-related burst activities were recorded from hypoglossal nerve rootlets before and during superfusion of the slice preparation with L-Arginine (L-Arg), sodium nitroprusside (SNP) or 7-nitro indazole (7-NI, an inhibitor of NO synthase). After perfusion with L-Arg and SNP, there was no significant change in respiratory rhythmical discharge activity (RRDA), but 7-NI decreased the integral amplitude of burst and inspiratory time. These results indicate that NO may take part in the inspiratory off-switching mechanism and that it also modulates the amplitude of respiratory-related bursts.
Animals ; Animals, Newborn ; Arginine ; pharmacology ; Brain Stem ; physiology ; Electrophysiology ; Indazoles ; Neurons ; physiology ; Nitric Oxide ; physiology ; Nitric Oxide Synthase ; antagonists & inhibitors ; Nitroprusside ; pharmacology ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Respiration ; Respiratory Center ; physiology

Patients with early cataract may have normal visual acuity ( VA ) but complain that they have problems in driving at night, like seeing things through a veil. This phenomenon is defined as disability glare which maybe caused by growing stray light. Patients with intraocular lens following cataract surgery may complain about glare, halos and shadows in visual field, which are also resulted from dysphotopia. Disability glare is the VA loss due to disturbing luminance in visual field. ln other words, it's the retinal contrast sensitivity reduction because of the straylight. This article contains the consensus and new progress of disability glare. lt provides solutions according to its effect factors and offers clues for further study.

Objective To conclude nursing experience of full series artificial liver support system in the treatment of acute fatty liver in pregnancy. Methods Development of artificial liver support system according to patient's condition, total continuous renal replacement therapy 7days, double plasma molecular absorb system 3 times, plasma replacement 3 times, molecular adsorbent circulation system 2 times. Results After treatment, the patient was discharged after 20 days in hospital. Conclusions The full range of artificial liver support system can effectively treat the patients with acute fatty liver in pregnancy, it will greatly reduce the mortality of patients with acute fatty liver in pregnancy.

The severe acute syndrome coronavirus 2(SARS-CoV-2)is responsible for the global pandemic of 2019 novel coronavirus disease(COVID-19). Understanding the pathogenic mechanisms of SARS-CoV-2 is of great significance to the prevention and control of the COVID-19 epidemic. The spike(S)protein of SARS-CoV-2 is a major target of protective immunity. The mutations of S protein impact the transmission and pathogenic capacity of SARS-CoV-2. In addition, angiotensin-converting enzyme 2(ACE2)is the receptor of SARS-CoV-2 S protein and mediates viral entry into target cells. The genetic polymorphisms of the ACE2 gene may lead to the difference of incidence of COVID-19 among different populations. Protease can promote the infection of SARS-Cov-2 by activating the S protein. This review summarized the current understanding of the function and genetic variants of S protein, ACE2, and the related proteases. The synergistic effect of these three molecules on the susceptibility of SARS-CoV-2 infection was further discussed.

Objective To explore the biological functions of retinoic acid-inducible gene-I(RIG-I) in vivo through phenotype analysis of RIG-I knockout mice. Methods The gene expression of RIG-Ⅰ in various tissues of mice was examined with Northern blotting and semi-quantitative RT-PCR.The phenotypes observed included body weight measurement,differential count of peripheral blood cells,metabolic parameters measurement and histopathologic examination. ResultsRIG-Ⅰ expressed in various tissues of mice with different levels.No gross developmental abnormalities and expected maturation arrest in granulocytic differentiation were observed in RIG-Ⅰ knockout mice.However,RIG-Ⅰ knockout mice exhibited an unexpected increase in the ratios of neutrophiles to lymphocytes in peripheral blood and increased susceptibility to bacteria infection. Conclusion RIG-Ⅰ may play an important role in immune regulation in mice.

A sample pretreatment method combining column clean-up with dispersive liquid-liquid microextraction (CCU-DLLME) for determination of polycyclic aromatic hydrocarbons (PAHs) in oil-field water was proposed. With this method,most organic interferences in matrix were cleaned up,and PAHs were purified, enriched and analyzed by gas chromatography/mass spectrometry directly. The influences on extraction efficiency including the kinds of column packing,weight ratio between column packing and sample, column flow rate,type and volume of extraction solvent, type and volume of disperser solvent and extraction time were investigated, respectively. Finally, 12 g of H103 macroporous resin was selected as column packing,12﹕5 of weight ratio between column packing and sample and 4 BV/h of column flow rate were selected in CCU. The resulting eluate was added with 1.00 mL of acetone (disperser solvent) and 15 μL of carbon tetrachloride (extraction solvent),followed by DLLME for 2 min. Under the optimum conditions,the enrichment factor of PAHs was 730-1579,the limits of detection (S/N=3) were 1.1-5.3 ng/L, the linear range was 0.01-50 μg/L,the RSDs(n=5) were 0.6%-3.4% and the recoveries were 82.6%-104.6%. This method could greatly reduce the influence of organic interferences in matrix, and was fit for the rapid analysis of pollutants in oil-field water especially.