Aim To investigate the effect of quercetin on the aging model of bone marrow mesenchymal stem cells established under microgravity. Methods Using 3D gyroscope, a aging model of bone marrow mesenchymal stem cells was constructed, and after receiving quercetin and microgravity treatment, the anti-aging effect of the quercetin was evaluated by detecting related proteins and oxidation indexes. Results Compared to the control group, the expressions of age-related proteins p21, pi6, p53 and RB in the microgravity group significantly increased, while the expressions of cyclin D1 and lamin B1 significantly decreased, with statistical significance (P<0.05). In the microgravity group, mitochondrial membrane potential significantly decreased (P<0.05), ROS accumulation significantly increased (P <0.05), SOD content significantly decreased and MDA content significantly increased (P<0.05). Compared to the microgravity group, the expressions of age-related proteins p21, pi6, p53 and RB in the quercetin group significantly decreased, while the expressions of cyclin D1 and lamin B1 significantly increased, with statistical significance (P<0.05). In the quercetin group, mitochondrial membrane potential significantly increased (P<0.05), ROS accumulation significantly decreased (P<0.05), SOD content significantly increased and MDA content significantly decreased (P<0.05). Conclusions Quercetin can resist oxidation, protect mitochondrial function and normal cell cycle, thus delaying the aging of bone marrow mesenchymal stem cells induced by microgravity.

Objective To investigate the toxicokinetic differences of 3,4-methylenedioxy-N-methylamphetamine(MDMA)and its metabolite 4,5-methylene dioxy amphetamine(MDA)in rats af-ter single and continuous administration of MDMA,providing reference data for the forensic identifica-tion of MDMA.Methods A total of 24 rats in the single administration group were randomly divided into 5,10 and 20 mg/kg experimental groups and the control group,with 6 rats in each group.The ex-perimental group was given intraperitoneal injection of MDMA,and the control group was given intraperi-toneal injection of the same volume of normal saline as the experimental group.The amount of 0.5 mL blood was collected from the medial canthus 5 min,30 min,1 h,1.5 h,2 h,4 h,6 h,8 h,10 h,12 h after administration.In the continuous administration group,24 rats were randomly divided into the experi-mental group(18 rats)and the control group(6 rats).The experimental group was given MDMA 7 d by continuous intraperitoneal injection in increments of 5,7,9,11,13,15,17 mg/kg per day,respectively,while the control group was given the same volume of normal saline as the experimental group by in-traperitoneal injection.On the eighth day,the experimental rats were randomly divided into 5,10 and 20 mg/kg dose groups,with 6 rats in each group.MDMA was injected intraperitoneally,and the con-trol group was injected intraperitoneally with the same volume of normal saline as the experimental group.On the eighth day,0.5 mL of blood was taken from the medial canthus 5 min,30 min,1 h,1.5 h,2 h,4 h,6 h,8 h,10 h,12 h after administration.Liquid chromatography-triple quadrupole tandem mass spectrometry was used to detect MDMA and MDA levels,and statistical software was employed for data analysis.Results In the single-administration group,peak concentrations of MDMA and MDA were reached at 5 min and 1 h after administration,respectively,with the largest detection time limit of 12 h.In the continuous administration group,peak concentrations were reached at 30 min and 1.5 h af-ter administration,respectively,with the largest detection time limit of 10 h.Nonlinear fitting equations for the concentration ratio of MDMA and MDA in plasma and administration time in the single-administration group and continuous administration group were as follows:T=10.362C-1.183,R2=0.974 6;T=7.397 3C-0.694,R2=0.961 5(T:injection time;C:concentration ratio of MDMA to MDA in plasma).Conclusions The toxicokinetic data of MDMA and its metabolite MDA in rats,obtained through single and continuous administration,including peak concentration,peak time,detection time limit,and the relationship between concentration ratio and administration time,provide a theoretical and data foundation for relevant forensic identification.

Objective To evaluate the clinical application value of matrix-assisted laser desorption ionization time-of-flight mass spectrometry(MALDI-TOF MS)in analyzing the homology of Acinetobacter baumannii(AB).Methods After excluding repetitive strains from multiple specimens of the same patient or environment,a total of 46 AB strains isolated from patients'sputum and environmental specimens of neurological intensive care unit(ICU)in a tertiary first-class general hospital from May 2020 to February 2021 were collected.Strains were detected by VITEK-MS mass spectrometer.Cluster analysis was performed by SARAMIS Premium software,and verified by multilocus sequence typing(MLST).Results Cluster analysis and comparison of MALDI-TOF MS and MLST found that among the 46 AB strains,39 were the type MS-a of MALDI-TOF MS,of which 22 strains were the clus-ter MT-A of MLST,including ST208(n=3),ST540(n=3),ST195(n=8),ST369(n=5),ST136(n=1),ST436(n=1)and ST1893(n=1);16 strains were MT-B,including type ST381(n=4),type ST469(n=11),and type ST938(n=1);one strain was cluster MT-C(ST1821);one strain of type MS-b was ST381;two strains of type MS-c were ST369;one strain of type MS-d was ST195;two strains of type MS-e were ST540 and ST369,respectively;one strain of type MS-f was STN1.Conclusion As a homology analysis method,MALDI-TOF MS still has certain limitations such as low consistency with MLST results,low resolution and specificity,thus cannot replace MLST technology.

To understand Helicobacter pylori's drug resistance,genetic diversity,and relationship with clinical diseases in the Guiyang and Qiannan minority areas of Guizhou Province,we collected samples through endoscopy,and isolated and cul-tured H.pylori.The drug resistance and genotype characteristics were determined.The differences in different regions and dis-ease types were compared,and the structural characteristics of H.pylori and mixed infections with different strains of H.py-lori in Qiannan Prefecture were analyzed.A difference in the composition ratio of EPYIA typing in the cagA variable region was observed between the two areas(P=0.012),and the composition ratio of the vacA genotype differed(P=0.000).A total of 94.6％(53/56)new sequences of H.pylori strains from two regions were obtained by MLST.The rate of infection by H.pylori mixed with different strains was 44.4％in Qiannan Pre-fecture,and no significant difference was observed in the com-position of H.pylori mixed infections among patients with dif-ferent clinical diseases(P=0.349).Differences in EPI YA typ-ing and the vacA genotype composition ratio in the cagA varia-ble region of H.pylori were observed between the Qiannan Prefecture and Guiyang City.

Activation of nuclear factor erythroid 2-related factor 2(Nrf2)by Kelch-like ECH-associated protein 1(Keap1)alkylation plays a central role in anti-inflammatory therapy.However,activators of Nrf2 through alkylation of Keap1-Kelch domain have not been identified.Deoxynyboquinone(DNQ)is a natural small molecule discovered from marine actinomycetes.The current study was designed to investigate the anti-inflammatory effects and molecular mechanisms of DNQ via alkylation of Keap1.DNQ exhibited signif-icant anti-inflammatory properties both in vitro and in vivo.The pharmacophore responsible for the anti-inflammatory properties of DNQ was determined to be the α,β-unsaturated amides moieties by a chemical reaction between DNQ and N-acetylcysteine.DNQ exerted anti-inflammatory effects through activation of Nrf2/ARE pathway.Keap1 was demonstrated to be the direct target of DNQ and bound with DNQ through conjugate addition reaction involving alkylation.The specific alkylation site of DNQ on Keap1 for Nrf2 activation was elucidated with a synthesized probe in conjunction with liquid chromatography-tandem mass spectrometry.DNQ triggered the ubiquitination and subsequent degra-dation of Keap1 by alkylation of the cysteine residue 489(Cys489)on Keap1-Kelch domain,ultimately enabling the activation of Nrf2.Our findings revealed that DNQ exhibited potent anti-inflammatory capacity through α,β-unsaturated amides moieties active group which specifically activated Nrf2 signal pathway via alkylation/ubiquitination of Keap1-Kelch domain,suggesting the potential values of targeting Cys489 on Keap1-Kelch domain by DNQ-like small molecules in inflammatory therapies.

The imprint desorption electrospray photoionization mass spectrometry was employed to locally image the spatial distribution of chemical components in dried tobacco leaves after initial curing. The relative content distribution of different chemical components was obtained in tobacco leaves. The application of imprinting method could transfer tobacco internal compounds to the surface of porous polytetrafluoroethylene plate,which realized the detection and visual analysis of tobacco internal substances. Besides,the imprint desorption electrospray ionization/post-photoionization (Imprint DESI/PI) mass spectrometry imaging technique had the advantages of non-polarity discrimination,soft ionization and high ionization efficiency for plant samples,and could simultaneously detect and image rich compounds in tobacco samples. A total of 40 kinds of chemical components including alkaloids,amino acids,sugars,acids,ketones and phenols were identified based on high resolution mass spectrometry. The results showed that the representative chemical components of tobacco,such as alkaloids,amino acids and sugars,were mainly distributed near the leaf tip from the vertical analysis and at the left and right leaf edges from the horizontal analysis. Amadori compound (1-Deoxy-1-L-proline-d-fructose) was detected,and the content of Amadori was found to be consistent with that of free amino acid (proline). In addition,the technique was further used to study the climate spot disease area of tobacco,and it was found that the compounds had specific distribution in the climate spot area,which further proved the superiority of this method in studying the growth stress of tobacco leaves.

To evaluate the effectiveness and safety of implantable D-shant atrial shunt device in patients with severe pulmonary arterial hypertension(PAH)and right heart failure.A 53-year-old female patient diagnosed with severe idiopathic PAH and right heart failure,her WHO FC grade was Ⅳ.The right heart catheter and implantation of D-shant atrial shunt device were performed under local anesthesia on November 30,2021.A 6 mm×4 cm peripheral artery balloon was selected to dilate the atrial septum and a D-shant atrial shunt device with a fixed 4 mm diameter orifice was implanted into the heart.The clinical symptoms and hemodynamics of the patient was improved after the intervention.Implantation of atrial shunt device as a palliative therapy to established a right to left shunt is another strategy for treating patients with severe PAH in late period,which has good effectiveness and safety.It could be the last replacement therapy to improve symptoms and prolonged lives to drug resistant and severe PAH patients.

The effect of porcine SIRT5 on replication of foot and mouth disease virus type O(FMDV-O)and the underlying regulatory mechanism were investigated.Western blot and RT-qPCR analyses were employed to monitor expression of endoge-nous SIRT5 in PK-15 cells infected with FMDV-O.Three pairs of SIRT5-specific siRNAs were synthesized.Changes to SIRT5 and FMDV-O protein and transcript levels,in addition to virus copy numbers,were measured by western blot and RT-qPCR analyses.PK-15 cells were transfected with a eukaryotic SIRT5 expression plasmid.Western blot and RT-qPCR analyses were used to explore the impact of SIRT5 overexpression on FMDV-O replication.Meanwhile,RT-qPCR analysis was used to detect the effect of SIRT5 overexpression on the mRNA expression levels of type I interferon-stimulated genes induced by SeV and FMDV-O.The results showed that expression of SIRT5 was up-regulated in PK-15 cells infected with FMDV-O and siRNA interfered with SIRT5 to inhibit FMDV-O replication.SIRT5 overexpression promoted FMDV-O replication.SIRT5 over-expression decreased mRNA expression levels of interferon-stimulated genes induced by SeV and FMDV-O.These results suggest that FMDV-O infection stimulated expression of SIRT5 in PK-15 cells,while SIRT5 promoted FMDV-O rep-lication by inhibiting production of type I interferon-stimula-ted genes.These findings provide a reference to further ex-plore the mechanism underlying the ability of porcine SIRT5 to promote FMDV-O replication.

Objective To explore the application of polysomnography combined with arterial spin labeling(ASL)perfusion magnetic resonance imaging in the diagnosis of insomnia.Methods Forty-two insomnia patients admitted to Department of Neurology were included as insomnia group,while 41 healthy subjects during the same period were included as control group.The two groups were assessed using sleep habits questionnaire,hospital anxiety and depression scale,polysomnography,and ASL perfusion magnetic resonance imaging.Results Compared with control group,insomnia group took significantly more time to fall asleep(P<0.05),and has shorter sleep duration(P<0.05).The differences in the levels of anxiety and depression between two groups were trivial.The total sleep time,rapid eye movement sleep duration,and non-rapid eye movement sleep stage S2-S4were shorter,while the sleep latency and non-rapid eye movement sleep stage S1were longer in insomnia group as compared with control group(all P<0.05).In insomnia group,perfusion was increased in bilateral prefrontal lobes,right temporal lobe,left parietal lobe,right thalamus,and pons(P<0.05),but decreased in bilateral insula and bilateral basal ganglia(P<0.05).Conclusion The combination of polysomnography and ASL perfusion magnetic resonance imaging enables precise quantification of sleep condition.

Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.