A rapid analytical method for simultaneous determination of 32 kinds of multi-residue veterinary drugs in eggs was developed using a modified QuEChERS technique based on a reduced graphene oxide-coated melamine sponge(r-GO@MeS)by ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The influences of graphene oxide(GO)concentrations,sponge dosages,and purification modes on drug recoveries were investigated during the purification process.The optimal purification conditions involved using a GO concentration of 0.5 mg/mL,a sponge dosage of 6.0 cm3/mL,and a dynamic purification mode of 5 extrusion cycles.Separation was achieved using an Agilent Eclipse Plus C18 RRHD column(100 mm×2.1 mm,1.8 μm),and quantitative analysis was performed by the external standard method using an electrospray ionization source(ESI)in multiple reaction monitoring(MRM)mode.The results showed that all 32 kinds of veterinary drugs exhibited good linear correlation with coefficients greater than 0.999,and matrix effects(MEs)ranging from?7.8%to 18.9%.The limits of detection(LODs)and quantification(LOQs)ranged from 0.2 to 10.2 μg/kg and from 0.6 to 28.0 μg/kg,respectively.The recoveries for the three spiked levels were in the range of 66.5%?117.5%,with intra-day and inter-day precision(Relative standard deviation)below 13.3%and 16.3%,respectively.The synthetic r-GO@MeS exhibited efficient matrix purification without the need of high-speed centrifugation or strong magnetic field assistance.This significantly shorted the sample pretreatment time and improved the convenience of the matrix purification process.Combined with UPLC-MS/MS,the method was suitable for the rapid determination of multi-residue veterinary drugs in eggs.

Cinnamomum camphora is an important economic tree species in China. According to the type and content of main components in the volatile oil of leaf, C. camphora were divided into five chemotypes, including borneol-type, camphor-type, linalool-type, cineole-type, and nerolidol-type. Terpene synthase(TPS) is the key enzyme for the formation of these compounds. Although several key enzyme genes have been identified, the biosynthetic pathway of(+)-borneol, which has the most economic value, has not been reported. In this study, nine terpenoid synthase genes CcTPS1-CcTPS9 were cloned through transcriptome analysis of four chemical-type leaves. After the recombinant protein was induced by Escherichia coli, geranyl pyrophosphate(GPP) and farnesyl pyrophosphate(FPP) were used as substrates for enzymatic reaction, respectively. Both CcTPS1 and CcTPS9 could catalyze GPP to produce bornyl pyrophosphate, which could be hydrolyzed by phosphohydrolase to obtain(+)-borneol, and the product of(+)-borneol accounted for 0.4% and 89.3%, respectively. Both CcTPS3 and CcTPS6 could catalyze GPP to generate a single product linalool, and CcTPS6 could also react with FPP to generate nerolidol. CcTPS8 reacted with GPP to produce 1,8-cineol(30.71%). Nine terpene synthases produced 9 monoterpene and 6 sesquiterpenes. The study has identified the key enzyme genes responsible for borneol biosynthesis in C. camphora for the first time, laying a foundation for further elucidating the molecular mechanism of chemical type formation and cultivating new varieties of borneol with high yield by using bioengineering technology.
Cinnamomum camphora/enzymology* ; Alkyl and Aryl Transferases/chemistry*

Female ; Humans ; Sarcoma, Endometrial Stromal/surgery* ; Transcription Factors/genetics* ; Endometrial Neoplasms/surgery* ; DNA-Binding Proteins ; Co-Repressor Proteins ; Repressor Proteins/genetics*

Stroke is the second leading cause of death in the world, of which about 60 % - 80 % are ischemic stroke. Ischemic stroke will inevitably cause the damage of neurons in the core area. With the increase of ischemic time, other neurons in the ischemic penumbra will also die due to the loss of " signal connection", and further lead to body dysfunction. In view of the complexity of neuronal death mechanism after ischemic stroke, understanding the action principle of death mechanism can better save ischemic penumbra neurons. This review mainly expounds several main mechanisms and potential therapeutic targets of neuronal death after ischemic stroke, so as to provide basis and help for the improvement of action mechanism research and drug development.

Aim To observe cellular damage and astrocyte activation at different time points of cerebral ischemia and reperfusion. Methods The middle cerebral artery of male SpragueDawley rats was occluded for 90 min followed by different time points of reperfusion. Eighty-five SPF male SD rats were randomly divided into control group (Sham), IR3, 6, 12, 24 and IR48h (MCAO followed by 48 h of reperfusion) group. Cerebral ischemia and reperfusion injury was observed by HE staining, and the structure of astrocytes was estimated with transmission electron microscopy (TEM). GFAP expression was detected by immunofluorescence staining and Western blot. Results Cerebral ischemia following by different time points of reperfusion led to different degrees of cellular damage, which was the most serious at 24 h of reperfusion. TEM showed destruction of astrocytes structure, swollen organelles and broken mitochondrial ridge. After cerebral ischemia-reperfusion, the expression levels of GFAP were significant up-regulated in the ischemic penumbra cortex and the highest was at 48 h of reperfusion, indicating astrocytes were activated. In addition, the results showed the gradual decrease in GFAP expression in the infarct core. Conclusions After cerebral ischemia-reperfusion, cellular damage is aggravated, and astrocytes are gradually activated in the ischemic penumbra. With the extension of reperfusion time, the boundaries of infarct area and ischemic area are gradually clear, and scarring may occur.

Ischemic stroke is the second leading cause of human death and the third reason of disability. Meanwhile, the incidence is rising year after year worldwide. Ischemic stroke could cause ischemia-reperfusion injury after blood recanalization treat-ment, but the mechanism of ischemia-reperfusion injury is still not very clear, so it is necessary to build a preclinical model with specific characteristics. Up to now, animal experiments have been still complicated, and the culture of brain slices has some limitations. The cell model in vitro has become a simplified and valuable tool widely used by researchers. The paper systematically summarizes the common type of nerve cells, and further analyzes establishment methods and principle, relevant research progress on the in vitro model of ischemia-reperfusion, in order to provide reference for rationally selecting hypoxia and reoxygenation model for basic research on cerebral ischemia and reperfusion and drug screening.

Uric acid (UA) is the final product of purine metabolism in human body,and its metabolic disorder will induce hyperuricemia (HUA).The occurrence and development of HUA are associated with a variety of pathological mechanisms such as oxidative stress injury,activation of inflammatory cytokines,and activation of renin-angiotensin-aldosterone system.These mechanisms directly or indirectly affect the bioavailability of endogenous nitric oxide (NO).The decrease in NO bioavailability is common in the diseases with high concentration of UA as an independent risk factor.In this review,we summarize the mechanisms by which high concentrations of UA affect the endogenous NO bioavailability,with a focus on the mechanisms of high-concentration UA in decreasing the synthesis and/or increasing the consumption of NO.This review aims to provide references for alleviating the multisystem symptoms and improving the prognosis of HUA,and lay a theoretical foundation for in-depth study of the correlations between HUA and other metabolic diseases.
Humans ; Nitric Oxide ; Uric Acid ; Hyperuricemia ; Biological Availability ; Cytokines

Objective: To summarize the management and short-term outcomes of neonates delivered by mothers infected with SARS-CoV-2 Omicron variant. Methods: A retrospective study was performed on 158 neonates born to mothers infected with SARS-CoV-2 Omicron variant admitted to the isolation ward of Children's Hospital of Fudan University from March 15^th, 2022 to May 30^th, 2022. The postnatal infection control measures for these neonates, and their clinical characteristics and short-term outcomes were analyzed. They were divided into maternal symptomatic group and maternal asymptomatic group according to whether their mothers had SARS-CoV-2 symptoms. The clinical outcomes were compared between the 2 groups using Rank sum test and Chi-square test. Results: All neonates were under strict infection control measures at birth and after birth. Of the 158 neonates, 75 (47.5%) were male. The gestational age was (38⁺³±1⁺³) weeks and the birth weight was (3 201±463)g. Of the neonates included, ten were preterm (6.3%) and the minimum gestational age was 30⁺¹ weeks. Six neonates (3.8%) had respiratory difficulty and 4 of them were premature and required mechanical ventilation. All 158 neonates were tested negative for SARS-COV-2 nucleic acid by daily nasal swabs for the first 7 days. A total of 156 mothers (2 cases of twin pregnancy) infected with SARS-CoV-2 Omicron variant, the time from confirmed SARS-CoV-2 infection to delivery was 7 (3, 12) days. Among them, 88 cases (56.4%) showed clinical symptoms, but none needed intensive care treatment. The peripheral white blood cell count of the neonates in maternal symptomatic group was significantly higher than that in maternal symptomatic group (23.0 (18.7, 28.0) × 10⁹ vs. 19.6 (15.4, 36.6) × 10⁹/L, Z=2.44, P<0.05). Conclusions: Neonates of mothers infected with SARS-CoV-2 Omicron variant during third trimester have benign short-term outcomes, without intrauterine infection through vertical transmission. Strict infection control measures at birth and after birth can effectively protect these neonates from SARS-CoV-2 infection.
Female ; Humans ; Infant ; Infant, Newborn ; Male ; Pregnancy ; COVID-19 ; Mothers ; Pregnancy Complications, Infectious/prevention & control* ; Retrospective Studies ; SARS-CoV-2

OBJECTIVES: To explore the optimal maintenance dose of caffeine citrate for preterm infants requiring assisted ventilation and caffeine citrate treatment. METHODS: A retrospective analysis was performed on the medical data of 566 preterm infants (gestational age ≤34 weeks) who were treated and required assisted ventilation and caffeine citrate treatment in the neonatal intensive care unit of 30 tertiary hospitals in Jiangsu Province of China between January 1 and December 31, 2019. The 405 preterm infants receiving high-dose (10 mg/kg per day) caffeine citrate after a loading dose of 20 mg/kg within 24 hours after birth were enrolled as the high-dose group. The 161 preterm infants receiving low-dose (5 mg/kg per day) caffeine citrate were enrolled as the low-dose group. RESULTS: Compared with the low-dose group, the high-dose group had significant reductions in the need for high-concentration oxygen during assisted ventilation (P=0.044), the duration of oxygen inhalation after weaning from noninvasive ventilation (P<0.01), total oxygen inhalation time during hospitalization (P<0.01), the proportion of preterm infants requiring noninvasive ventilation again (P<0.01), the rate of use of pulmonary surfactant and budesonide (P<0.05), and the incidence rates of apnea and bronchopulmonary dysplasia (P<0.01), but the high-dose group had a significantly increased incidence rate of feeding intolerance (P=0.032). There were no significant differences between the two groups in the body weight change, the incidence rates of retinopathy of prematurity, intraventricular hemorrhage or necrotizing enterocolitis, the mortality rate, and the duration of caffeine use (P>0.05). CONCLUSIONS This pilot multicenter study shows that the high maintenance dose (10 mg/kg per day) is generally beneficial to preterm infants in China and does not increase the incidence rate of common adverse reactions. For the risk of feeding intolerance, further research is needed to eliminate the interference of confounding factors as far as possible.
Caffeine/therapeutic use* ; Citrates ; Humans ; Infant ; Infant, Newborn ; Infant, Premature ; Respiration, Artificial ; Retrospective Studies

Objective:To explore the underlying protective mechanism of Kaixinsan on learning， memory， and synaptic function in APP/PS1 mice. Method:Sixty APP/PS1 mice were randomly divided into a model group， a donepezil （2 mg·kg^-1·d^-1） group， and low- （0.7 g·kg^-1·d^-1）， medium- （1.4 g·kg^-1·d^-1）， and high-dose （2.8 g·kg^-1·d^-1） Kaixinsan groups， and the wild-type mice of the same age in the same litter were assigned to the normal group， with 12 mice in each group. After continuous intragastric administration for two months， the Morris water maze experiment was performed. The ultrastructure of hippocampal neurons was observed by transmission electron microscopy. The colorimetric assay was used to detect serum content of acetylcholine （ACh）， choline acetyltransferase （ChAT）， acetylcholinesterase （AChE）， and levels of hippocampal reactive oxygen species （ROS）， malondialdehyde （MDA）， superoxide dismutase （SOD）， and glutathione peroxidase （GSH-Px）. Real-time fluorescence-based quantitative polymerase chain reaction （Real- time PCR） was used to detect the mRNA expression of hippocampal brain-derived neurotrophic factor （BDNF）， beta-nerve growth factor （NGFB）， discs large homolog (DLG)2， DLG4， and synaptophysin （SYP）. Result:Compared with the normal group， the model group showed prolonged escape latency， reduced number of crossing platforms， shortened stay in the target quadrant （P<0.01）， decreased number of mitochondria with different shapes and irregular arrangement， some swollen and deformed mitochondria with broken mitochondrial cristae， endolysis， and cytoplasm vacuole， and more cell debris. Additionally， the model group also displayed reduced serum levels of ACh and ChAT， increased AChE （P<0.01）， elevated hippocampal ROS and MDA （P<0.05，P<0.01）， declining SOD and GSH-Px （P<0.01）， and diminished hippocampal BDNF， NGFB， DLG2， DLG4， and SYP mRNA levels （P<0.05，P<0.01）. Compared with the model group， the donepezil group， and the medium- and high-dose Kaixinsan groups showed shortened escape latency， increased number of crossing platforms， prolonged stay in the target quadrant （P<0.05，P<0.01）， improved mitochondrial damage with a regular shape （mainly oval shape）， relieved mitochondrial swelling and deformation， and clear mitochondrial cristae. Furthermore， the donepezil group， and the medium- and high-dose Kaixinsan groups also exhibited increased serum ACh and ChAT levels （P<0.05，P<0.01）， blunted AChE activity （P<0.05）， reduced hippocampal ROS level （P<0.05，P<0.01）， declining MDA level （P<0.05）， potentiated SOD and GSH-Px activities， and up-regulated hippocampal BDNF， NGFB， DLG2， DLG4， and SYP mRNA levels （P<0.05，P<0.01）. In the low-dose Kaixinsan group， the stay time in the target quadrant was prolonged and the expression of hippocampal SYP mRNA was elevated significantly （P<0.05）. There was no statistical difference in swimming speed between the groups. Conclusion:Kaixinsan can improve the learning and memory ability of APP/PS1 mice by increasing the expression of synaptic plasticity-related proteins， reducing the ultrastructural damage to hippocampal neurons， resisting oxidative stress， and regulating cholinergic neurotransmitters， thereby exerting neuroprotective effects.