Objective To investigate the effect of dexmedetomidine(Dex)on propofol-induced nerve injury in neo-natal rats.Methods The rats were divided into control group,intra-peritoneally injected propofol to construct nerve injury model group(50 mg/kg),Low,medium and high dose dexmedetomidine intervention model groups(Dex-L,Dex-M and Dex-H with femoral vein injection of 0.25,0.5 and 1 μg/kg Dex,respectively),and Dex-H+anti-BDNF(10 0μg/kg)group,with 12 animals in each group.The neurological deficit score,number of platform jumping errors,and changes in brain index were detected in rats.HE staining microscopy was applied to measure pathology in the hippocampal CA1 region.ELISA was applied to detect level of interleukin-6(IL-6),monocyte chemotactic protein-1(MCP-1)and tumor necrosis factor-α(TNF-α)in the hippocampal CA1 region.TUNEL staining microscopy was used to measure neuronal apoptosis in the hippocampal CA1 region.Western blot was ap-plied to measure the cleaved caspase-3,proBDNF,mature brain-derived neurotrophic factor(mBDNF),phospho-rylated tyrosine kinase B(p-TrkB),and phosphorylated phosphatidylinositol 3 kinase(p-PI3K)proteins in the hippocampal CA1 region.Results Compared with model group,the neuronal damage in rats was improved in Dex-L group,Dex-M group,and Dex-H group,the neurological deficit score,number of platform jumping errors,brain index,level of IL-6,MCP-1,TNF-α in hippocampal CA1 region,neuronal apoptosis rate,and level of cleaved caspase-3 and pro BDNF proteins all reduced,mBDNF,p-TrkB,and p-PI3K proteins in the hippocampal CA1 re-gion raised(P＜0.05).Anti-BDNF inhibited the effect of 1 μg/kg Dex pretreatment on propofol induced nerve inju-ry in neonatal rats.Conclusions Dex pretreatment inhibits neuro-inflammation and neuronal apoptosis,thereby re-duces propofol induced nerve injury in neonatal rats.Its mechanism may be related to the activation of the mBDNF/TrkB/PI3K pathway.

Objective To assess the impact of freeze-drying and dry heat virus inactivation processes on the activity ofα2-macroglobulin(A2M)derived from human plasma Cohn fraction Ⅳ.Methods A2M derived from human plasma Cohn fraction Ⅳ was prepared and subjected to programmed freeze-drying with dry heat virus inactivation.The lyophilized products were evaluated for their appearance,water content,and validation of the viral inactivation process.The bioactivity of the products before and after lyophilization as well as before and after dry heat inactivation was determined via trypsin inhibition,and the comparisons were studied.Results The appearance of the lyophilized product was fluffy,and the water content was(5.83±0.45)％.The specific activities of the samples before and after lyophilization were(10.199±0.137)and(10.033±0.201)μg/mg,respectively,with no statistically significantdifference between the two groups(P＞0.05).The viral inactivation of the samples was carried out by using dry heat inactivation conditions at 100 ℃ for 30 min.After inactivation,the reduction was ≥5.125 LgTCID50/0.1 mL in Pseudorabies virus(PRV)titers,≥4.500 LgTCID50/0.1 mL in Sindbis virus(SinV)titers,≥6.375 LgTCID50/0.1 mL in encephalomyocarditis virus(EMCV)titers,and≥4.500 LgTCID50/0.1 mL in porcine parvovirus(PPV)titers.The specific activities of the samples before and after dry heat were(9.921±0.292)and(10.091±0.278)μ g/mg,respectively,with no statistically significant difference between the two groups.Conclusion A2M derived from human plasma Cohn fraction Ⅳ,when subjected to freeze-drying followed by dry heat inactivation at 100 ℃ for 30 minutes,can effectively inactivate viruses without altering the biological activity of the product.

Rheumatoid arthritis is a chronic, systemic autoimmune disease predominantly based on joint lesions with an extremely high disability and deformity rate. Several drugs have been used for the treatment of rheumatoid arthritis, but their use is limited by suboptimal bioavailability, serious adverse effects, and nonnegligible first-pass effects. In contrast, transdermal drug delivery systems (TDDSs) can avoid these drawbacks and improve patient compliance, making them a promising option for the treatment of rheumatoid arthritis (RA). Of course, TDDSs also face unique challenges, as the physiological barrier of the skin makes drug delivery somewhat limited. To overcome this barrier and maximize drug delivery efficiency, TDDSs have evolved in terms of the principle of transdermal facilitation and transdermal facilitation technology, and different generations of TDDSs have been derived, which have significantly improved transdermal efficiency and even achieved individualized controlled drug delivery. In this review, we summarize the different generations of transdermal drug delivery systems, the corresponding transdermal strategies, and their applications in the treatment of RA.

ObjectiveTo observe the effect of the Fangfeng Tongshengsan on post-chemoembolization syndrome with primary liver cancer or postoperative liver metastases of colorectal cancer. MethodSeventy-two patients suffered from post-chemoembolization syndrome after transcatheter hepatic arterial chemoembolization were randomly divided into 2 groups， including a Fangfeng Tongshengsan group and a control group， with 36 patients in each group. The patients in Fangfeng Tongshengsan group orally took the decoction for consecutive 7 d. The patients in the control group were physically cooled down with alcohol rub bath and ice pack for consecutive 7 d. Furthermore， the difference of fever， Karnofsky performance status （KPS）， pain in the liver region， nausea vomiting， constipation， and liver function between these two groups were observed. ResultCompared with the control group， Fangfeng Tongshengsan significantly relieved fever， reduced the body temperature （P<0.05）， and shortened the duration of fever （P<0.05）， indicating that Fangfeng Tongshengsan remarkably improved the KPS （P<0.05）. Meanwhile， Fangfeng Tongshengsan obviously alleviated nausea， vomiting， and constipation status and shortened the duration time compared with the control group （P<0.05）. In addition， the parameters of liver function including alanine aminotransferase （ALT）， aspartate aminotransferase （AST）， γ-glutamyl transpeptidase （GGT）， and total bilirubin （TBIL） were significantly decreased in the Fangfeng Tongshengsan group （P<0.05）， which indicated that Fangfeng Tongshengsan alleviated liver dysfunction of patients with post-chemoembolization syndrome. ConclusionFangfeng Tongshengsan can be used to treat post-chemoembolization syndrome with primary liver cancer and postoperative liver metastases of colorectal cancer.

Objective:To investigate the clinicopathological features of central nervous system (CNS) mesenchymal chondrosarcoma (MCS).Methods:Nine cases of CNS MCS were collected at the First Affiliated Hospital of Fujian Medical University from September 2010 to September 2020. The clinical,imaging,histopathological and immunohistochemical features were reviewed. NCOA2 gene rearrangement was evaluated by fluorescence in situ hybridization (FISH).Results:There were three male and six female patients, with age range of 1 to 59 years (median 31 years). Six cases were intracranial and three cases were intraspinal, and the tumors showed dural attachment. They were often diagnosed as meningioma basing on preoperative imaging. Microscopically, the tumors showed a characteristic biphasic histologic pattern composed of undifferentiated mesenchymal small cells and well-differentiated hyaline cartilage islands. The small cells area were positive for SOX9 (9/9), CD99 (8/9), and without BRG1 and INI1 deletion. The cartilaginous component expressed SOX9 (9/9) and S-100 protein (8/9). NCOA2 gene break apart signal was identified in five cases (5/5). Eight patients were followed up for 4-124 months. Three patients (3/8) had recurrences within one year and two patients died of the tumor.Conclusions:CNS MCS is an extremely rare malignant neoplasm with a propensity to dural involvement. Preoperative imaging has low diagnostic accuracy. CNS MCS should be differentiated from other CNS small round cell tumors and chondrosarcoma. FISH detection of NCOA2 gene rearrangement will assist the diagnosis of MCS.

We developed a high-efficiency microfluidic chip for extracting exosomes from human plasma. We collected peripheral blood from normal human, designed and fabricated a microfluidic chip based on nanoporous membrane and agarose gel electrophoresis to isolate exosomes. The extracted exosomes were characterized by transmission electron microscopy, nanosight and Western blotting, the morphology, concentration and particle size of exosomes were identified and analyzed. Meanwhile, we used ultracentrifugation and microfluidic chip to isolate exosomes separately. The particle size and concentration of the exosomes extracted by two methods were compared and analyzed, and their respective extraction efficiency was discussed. Finally, the expression level of miRNA-21 in exosomes was analyzed by RT-PCR. The microfluidic chip isolated (in 1 hour) high-purity exosomes with size ranging from 30-200 nm directly from human plasma, allowing downstream exosomal miRNA analysis. By comparing with ultracentrifugation, the isolation yield of microfluidic chip was 3.80 times higher than ultracentrifugation when the volume of plasma sample less than 100 μL. The optimized parameters for exosome isolation by gel electrophoresis microfluidic chip were: voltage: 100 V; concentration of agarose gel: 1.0%; flow rate of injection pump: 0.1 mL/h. The gel electrophoresis microfluidic chips could rapidly and efficiently isolate the exosomes, showing great potential in the research of exosomes and cancer biomarkers.
Exosomes ; Humans ; MicroRNAs/genetics* ; Microfluidics ; Plasma ; Ultracentrifugation

Objective:To confirm the first imported Chikungunya fever (CHIK) epidemic in Hunan province.Methods:Serum samples of patients and colleagues were collected. The nucleic acids of Dengue virus (DENV), Yellow fever virus (YFV), Chikungunya virus (CHIKV) were detected by real- time fluorescent quantitative PCR. The positive PCR products were sequenced. Phylogenetic tree was constructed.Results:The serum samples of the patient and one of the five colleagues were positive for CHIKV. The Blast comparison of gene sequence showed 99% homology with CHIKV sequences. The infected CHIKV belonged to ECSA genotype in the phylogenetic tree.Conclusions:The first imported CHIK epidemic in Hunan province was confirmed through the epidemiological survey and etiologic detection.

Objective:To analyze the epidemiological and etiological characteristics of a dengue fever outbreak in Hunan province in 2018.Methods:Real-time PCR assay was performed for the laboratory diagnosis of 8 suspected dengue fever cases. Etiological surveillance was performed in 186 suspected dengue fever cases and fever cases who had close contacts with dengue fever patients. C6/36 cells was used for the virus isolation from acute phase serum. By sequencing the full length of E genes of 15 dengue virus strains, phylogenetic analysis was performed based on the sequences obtained, including reference sequences from the NCBI GenBank database, the serotypes and gene subtypes of the virus were analyzed to trace the possible source of transmission. An emergency monitoring of vector density and a retrospective survey of sero-epidemiology in healthy population were conducted in the epidemic area.Results:In the serum samples of 8 suspected patients, 6 were dengue virus RNA positive, and 4 were NS1 antigen positive. In 186 suspected patients, 96 were dengue virus nucleic acid, NS1 antigen or antibody positive in etiological test. A total of 64 dengue virus strains were isolated. The phylogenetic analysis showed that all the dengue virus strains belonged to type 2, which might be from Guangdong or Zhejiang provinces. The Bretub index was up to 65, indicating an extremely high risk of transmission. The positive rate of the dengue virus IgG antibody was 0.53%(2/377) in retrospective survey of 377 healthy people.Conclusion:The field epidemiologic and the molecular genetics analyses showed the outbreak of dengue fever in Hunan in 2018 was caused by imported cases and dengue virus 2.

Objective To evaluate the effect of dexmedetomidine pretreatment on the expression of mitochondrial transcription factor A ( TFAM) and succinate dehydrogenase ( SDHA) during lung ischemia-reperfusion ( I∕R) in mice. Methods Twenty-four clean-grade healthy male C57BL∕6J mice, aged 8-10 weeks, weighing 18-22 g, were divided into 3 groups ( n=8 each) using a random number table method:sham operation group ( group S ) , lung I∕R group ( group I∕R ) and dexmedetomidine pretreatment group ( group D) . In I∕R and D groups, lung I∕R was induced by clamping the left pulmonary hilum for 60 min followed by 120-min reperfusion in anesthetized mice. The chest was only opened, but the left pulmonary hilum was not occluded in group S. Dexmedetomidine 25μg∕kg was intraperitoneally injected at 30 min be-fore ischemia in group D, while the equal volume of normal saline was given instead of dexmedetomidine in I∕R and S groups. The mice were sacrificed at 120 min of reperfusion, and lungs were removed for determi-nation of wet∕dry weight ratio ( W∕D ratio) , cell apoptosis ( by TUNEL) and expression of TFAM and SDHA mRNA in lung tissues ( by real-time polymerase chain reaction ) and for examination of the pathological changes of lung tissues. The apoptosis index was calculated. Results Compared with group S, the W∕D ratio, apoptosis index and lung injury scores were significantly increased, and the expression of TFAM and SDHA mRNA was down-regulated in I∕R and D groups ( P<0. 05) . Compared with group I∕R, the W∕D ra-tio, apoptosis index and lung injury scores were significantly decreased, and the expression of TFAM and SDHA mRNA was up-regulated in group D ( P<0. 05) . Conclusion The mechanism by which dexmedeto-midine pretreatment attenuates lung I∕R injury is related to up-regulating the expression of TFAM and SDHA in mice.

Objective To investigate the capsular polysaccharide (CPS) serotypes and molecular characteristics of carbapenem resistant hypermucoviscous Klebsiella pneumoniae (CR-HMKP) and study the possible mechanism of carbapenem resistance. Methods A retrospective study was conducted on 18 nonduplicate CR-HMKP strains which were collected from the First Affiliated Hospital of Nanchang University from 2012 to 2016. The clinical data were retrieved from medical records. The capsular serotypes, resistance genes and virulence factors were detected by polymerase chain reaction and DNA sequencing. Antimicrobial susceptibility testing was determined on VITEK 2 compact system. The CR-HMKP strains were characterized molecularly by using PCR, multilocus sequence typing (MLST) and pulsed field gel electrophoresis (PFGE). Modified carbapenem inactivation method was used to screen carbapenemase-producing strains. Plasmid conjugation transfer experiments were carried out to study transmission of carbapenem resistance. Results Eighteen (2.7％) CR-HMKP isolates were identified, which belonged to 4 serotypes, including wzi128-K1 (n=1), wzi206-K57 (n=1), wzi2-K2 (n=2), and wzi64-K14.64 (n=14). PCR and sequencing analysis identified blaNDM-1 gene in 2 CR-HMKP strains, blaKPC-2 gene in 17 strains, qnrS1 gene in 18 strains, blaCTX-M-3 gene in 3 strains, blaCTX-M-14 gene in 18 strains, blaTEM-1 gene in 16 strains, blaSHV-12 gene in 17 strains, and rmtB in 5 strains. All the 18 CR-HMKP strains carried virulence-associated genes, including rmpA (88.9％, 16/18), magA (5.6％, 1/18), iroN (83.3％, 15/18), aerobactin (27.8％, 5/18), rmpA2 (66.7％, 12/18) and mrkD (100％, 18/18). Three sequence types (STs) were identified by MLST, including ST11 (15 strains), ST86 (2 strains), and ST412 (1 strain). PFGE resulted in three major PFGE clusters, of which cluster A corresponds to ST1 isolates, and cluster B corresponds to ST86 isolates, and cluster C corresponds to ST412 isolates. All the blaKPC-2- positive strains belonged to ST11. Plasmid conjugation was successful in 5 (27.8％) of the 18 CR-HMKP isolates. Conclusions wzi64-K14.64 is the predominant capsule serotype of the CR-HMKP strains in this hospital. KPC-2 gene conjugationmay contribute to the emergence of CR-HMKP isolates. In addition, CRHMKP strain may be the highly prevalent ST11, and highly virulent CPS serotypes harboring K1/K2.