Aim To explore the effects of D-limonene on the steatosis of primary mouse hepatocytes and its potential mechanism of action.Methods Oleic acid-induced steatosis in primary mouse hepatocytes was used as a model to observe the effects of D-limonene on cell viability,cellular lipid content,and intracellular expression of proteins such as AMP-activated protein kinase(AMPK),acetyl-coenzyme A carboxylase 1(ACC1),and carnitine palmitoyl transferase 1A(CPT1A).Results It was found that a low dose of D-limonene could effectively enhance the viability of primary mouse hepatocytes.When oleic acid at a con-centration of 300 μmol·L-1 successfully induced steatosis in primary mouse hepatocytes,D-limonene re-duced the lipid content of the cells,and D-limonene up-regulated the cellular AMPK expression level,down-regulated the cellular ACC1 and fatty acid synthetase(FAS)expression levels,which in turn promoted the overexpression of CPT1A.Conclusions D-limonene has the effect of reducing lipid deposition in primary mouse hepatocytes,and the mechanisms may be related to the activation of AMPK,the inhibitions of ACC1 and FAS,and the up-regulation of CPT1A protein expres-sion level.

Aim To explore the effects of D-limonene on the steatosis of primary mouse hepatocytes and its potential mechanism of action.Methods Oleic acid-induced steatosis in primary mouse hepatocytes was used as a model to observe the effects of D-limonene on cell viability,cellular lipid content,and intracellular expression of proteins such as AMP-activated protein kinase(AMPK),acetyl-coenzyme A carboxylase 1(ACC1),and carnitine palmitoyl transferase 1A(CPT1A).Results It was found that a low dose of D-limonene could effectively enhance the viability of primary mouse hepatocytes.When oleic acid at a con-centration of 300 μmol·L-1 successfully induced steatosis in primary mouse hepatocytes,D-limonene re-duced the lipid content of the cells,and D-limonene up-regulated the cellular AMPK expression level,down-regulated the cellular ACC1 and fatty acid synthetase(FAS)expression levels,which in turn promoted the overexpression of CPT1A.Conclusions D-limonene has the effect of reducing lipid deposition in primary mouse hepatocytes,and the mechanisms may be related to the activation of AMPK,the inhibitions of ACC1 and FAS,and the up-regulation of CPT1A protein expres-sion level.

Objective To establish a method to identify an unknown substance based on the combined use of gas chromatography-quadrupole time-of-flight mass spectrometry(GC-QTOF-MS),ultra-high performance liquid chromatography-quadrupole/electrostatic field orbitrap high resolution mass spectrometry(UPLC-Q/Orbitrap HRMS)and nuclear magnetic resonance(NMR)techniques.Methods The unknown substance was dissolved in methanol and was detected by GC-QTOF-MS and UPLC-Q/Orbitrap HRMS,and was dissolved in methanol-d4 to be detected by NMR.Results The main characteristics ion peaks of components with retention time of 9.67 min in GC-QTOF-MS measured were 84.080 8,110.999 7,128.107 0(base peak),138.994 7,etc.The protonated molecular ion peak m/z in UPLC-Q/Orbitrap HRMS was 268.109 3.It was inferred that the unknown substance was an analog of the syn-thetic cathinone substance 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one(MTMP)by comparing the mass spectrum information and molecular structure of MTMP.NMR analysis confirmed it as a novel N-morpholine substituted synthetic cathinone substance 1-(4-chlorophenyl)-2-methyl-2-morpholinopropan-1-one(CMMP).Conclusion The method established in this study can be used for structural confirmation of CMMP.

Objective To establish a rapid screening method for 60 types of natural toxins in whole blood by ultra-high performance liquid chromatography-quadrupole/electrostatic field orbitrap high reso-lution mass spectrometry(UPLC-Q/Orbitrap HRMS).Methods The chromatographic and mass spectro-metric information of 60 standard samples of natural toxins were analyzed and recorded,and a screening database was built.Whole blood was pretreated by protein precipitation method combined with ultrasonic-assisted dispersion,and then a Hypersil GOLDTM C18 column was used with 5 mmol/L ammonium for-mate aqueous solution(containing 0.1%formic acid)and acetonitrile as mobile phase for gradient elu-tion.In the positive ion mode,the data were collected in full scan/data-dependent secondary scan(Full MS/dd-MS2)mode.Based on the established screening library,the rapid screening of 60 types of natural toxins in whole blood was realized by TraceFinder software.Results A UPLC-Q/Orbitrap HRMS method was developed for the screening of 60 types of natural toxins in whole blood.Except for the limit of detection(LOD)of oxymatrine(20 ng/mL)and strophanthidin(40 ng/mL),the LOD for the other 58 natural toxins was in the range of 0.05-5 ng/mL.Conclusion This method has a simple and efficient pretreatment process and can achieve rapid screening of 60 types of natural toxins in whole blood.

In 2004, it was the first time that Wollensak and Spoerl had applied physical and chemical cross-linking methods to scleral tissue. They found that the biomechanical strength of cross-linked sclera, induced by riboflavin/ultraviolet A, glyceraldehyde and glutaraldehyde, could be improved and proposed that scleral collagen cross-linking is expected to be a new method for the treatment of pathologic myopia. In recent years, a series of explorations have been made on the effectiveness and adverse reactions of physical and chemical cross-linking in the prevention and treatment of pathologic myopia, including the establishment of various animal models and different myopia modeling methods, the improvement of cross-linking methods, the amelioration of the measurement of biomechanical strength of scleral tissue and the attention of biological parameters such as the thickness of retinal nerve fiber layer and the amplitude of electroretinogram in vivo. Genipin-crosslinking of the scleral collagen combined with posterior scleral contraction/reinforcement has been applied to clinical research. This review summarizes physical cross-linking and the genipin-crosslinking of scleral collagen to explore the effectiveness and safety of the methods in the prevention and treatment of the pathologic myopia.

Hydrofluoric acid is a highly dangerous and toxic inorganic acid, which is widely used in industrial fields and daily life. The risk of hydrofluoric acid burns is related to hydrofluoric acid mass fraction, duration of exposure to hydrofluoric acid, burn area, burn depth, and burn site, etc. Hydrofluoric acid has strong toxicity and tissue penetration ability. A small area of hydrofluoric acid burns can cause death in a short time. Therefore, improving the understanding of the mechanism of hydrofluoric acid burns and learning how to treat hydrofluoric acid burns in different sites can further improve the cure rate of hydrofluoric acid burns.
Burns, Chemical/therapy* ; Calcium Gluconate ; Humans ; Hydrofluoric Acid/adverse effects*

AIM:A total of 1 084 preschool children in 4 kindergartens in Xining City were surveyed on their visual acuity and refraction status to find out abnormal vision and refraction beyond the normal range. METHODS: A cross-sectional survey study. The overall sampling method was used on October 2019, a total of 1 084 preschool children aged 3-6 years were selected from a kindergarten in the east, west, south and north of Xining City. The children were checked for uncorrected distance vision and refractive status was checked by using a refractive screener.RESULTS: The detection rate of abnormal vision in preschool children in Xining City was 12.21%, and the detection rate of abnormal vision increased with the increasing age(χ2lineartrend=94.40, P<0.05), and there were differences among different age groups(χ2=293.55, P<0.05). Refractive abnormalities accounted for 6.09% of the total number of examinations. With the increasing age, the proportion of compound hyperopic astigmatism decreased(χ2lineartrend=1.79, P>0.05).CONCLUSION: The abnormal visual acuity of preschool children in Xining City gradually increases with the increasing age; The refractive state is dominated by astigmatism, among which the proportion of mixed astigmatism and pure myopia astigmatism is the highest, followed by pure hyperopic astigmatism and compound hyperopic astigmatism; With the increase of age, the diopter of compound hyperopic astigmatism gradually decreases, which is in line with the law of children's eye refractive development.

BACKGROUND: Perioperative treatment has become an increasingly important aspect of the management of patients with non-small cell lung cancer (NSCLC). Small-scale clinical studies performed in recent years have shown improvements in the major pathological remission rate after neoadjuvant therapy, suggesting that it will soon become an important part of NSCLC treatment. Nevertheless, neoadjuvant immunotherapy may be accompanied by serious adverse reactions that lead to delay or cancelation of surgery, additional illness, and even death, and have therefore attracted much attention. The purpose of the clinical recommendations is to form a diagnosis and treatment plan suitable for the current domestic medical situation for the immune-related adverse event (irAE). METHODS: This recommendation is composed of experts in thoracic surgery, oncologists, thoracic medicine and irAE related departments (gastroenterology, respirology, cardiology, infectious medicine, hematology, endocrinology, rheumatology, neurology, dermatology, emergency section) to jointly complete the formulation. Experts make full reference to the irAE guidelines, large-scale clinical research data published by thoracic surgery, and the clinical experience of domestic doctors and publicly published cases, and repeated discussions in multiple disciplines to form this recommendation for perioperative irAE. RESULTS: This clinical recommendation covers the whole process of prevention, evaluation, examination, treatment and monitoring related to irAE, so as to guide the clinical work comprehensively and effectively. CONCLUSIONS Perioperative irAE management is an important part of immune perioperative treatment of lung cancer. With the continuous development of immune perioperative treatment, more research is needed in the future to optimize the diagnosis and treatment of perioperative irAE.

Objective To detect the uncontrolled new psychoactive tryptamines involved in drug-related cases with high resolution mass spectrometry and nuclear magnetic resonance spectroscopy. Methods White and brown powder obtained in actual cases were extracted and analyzed by gas chromatography-quadrupole time-of-flight mass spectrometry （GC-QTOF-MS）, ultra-high performance liquid chromatography-linear ion trap quadrupole-orbitrap mass spectrometry （UPLC-LTQ-Orbitrap MS） and ¹H-nuclear magnetic resonance spectroscopy （1H-NMR）. Results After detection by GC-QTOF-MS, the components of white powder showed main characteristic fragment ion peaks at m/z 218.141 0 （molecular ion peak）, 72.080 6 （base peak）, etc. After detection by UPLC-LTQ-Orbitrap MS, its protonated molecular ion was m/z 219.149 4. The main ions in the secondary mass spectrum under the collision-induced dissociation （CID） mode were m/z 160.076 3 and 72.080 8. After detection by GC-QTOF-MS, the components of brown powder showed main characteristic fragment ion peaks at m/z 246.135 7 （molecular ion peak）, 58.065 1 （base peak）, etc. After detection by UPLC-LTQ-Orbitrap MS, its protonated molecular ion was m/z 247.145 0. The main ions in the secondary mass spectrum under CID mode were m/z 202.087 1, 160.076 3 and 134.060 5. NIST 17 library retrieval and ¹H-NMR confirmed that the white powder and brown powder contained new psychoactive tryptamines 4-OH-MET and 4-AcO-DMT, respectively. Conclusion GC-QTOF-MS, UPLC-LTQ-Orbitrap MS and ¹H-NMR can be used together to identify unknown new psychoactive substances.
Chromatography, High Pressure Liquid ; Gas Chromatography-Mass Spectrometry ; Magnetic Resonance Spectroscopy ; Mass Spectrometry ; Tryptamines

Abstract.
N,N-Dimethyltryptamine