The genomic island(GI)characteristics and virulence factor differences of clinical isolates of Burkholderia pseudomallei in Hainan Province,China were analyzed to provide a scientific basis for diagnosis and treatment of melioidosis.In total,52 B.pseudomallei isolates were collected for detection of virulence-related GIs by PCR.The whole genome sequence annotation format file was submitted on Islandviwer 4 platform,and the genomes of the same species and close relatives were added for comparison.Two algorithms,SIGI-HMM and IslandPath-DIMOB,were integrated to predict GIs and sequence a-lignments were conducted to identify specific GIs and differences in virulence factors.The genomes of 52 clinical strains could be divided into three branches based on evolutionary distance,with 82.69％(43/52)of strains concentrated in branch 1.In to-tal,828 GIs were identified among the 52 B.pseudomallei genomes,which formed 157 GI clusters based on sequence similari-ty.GIs accounted for 2.05％-6.38％of the genome content.While GI clusters 1 and 2 were present in all strains,a total of 84(53.50％)GI clusters only clustered within a single genome isolate.Of 10 GI likely specific clusters,five were from the same genus,two from another genus,and three with uncertain origins.Moreover,25 GI clusters were associated with virulence,which included eight shared by B.pseudomallei BP76 and BP169,which had the highest number of virulence-associated GIs among all isolates.O the 52 B.pseudomallei isolates,variations were identified in the virulence genes fhaB1,fhaB2,BPSL1661,cheY1,wzM,tssH-5/clpV,tssA-5,boaA,and boaB.Comparisons of these findings with clinical isolates from Thailand and Australia showed that B.pseudomallei isolates from Hainan had significant differences in the sequences of boaA,boaB,cheY1,and chbp.Additionally,fhaB1,fhaB3,and bimA displayed significant variations specifically within the Australian isolates.B.pseudomallei GI was conserved and specific to Hainan.The identification of specific GI and virulence factors was useful to clarify the source of horizontal gene transfer and differences in virulence at the molecular level.

A prokaryotic expression vector for the mutant diphtheria toxin CRM197 was constructed and expressed in Esch-erichia coli cells.Anti-CRM197 antibody concentrations were detected in serum samples of healthy volunteers.The crm 197 gene was codon-optimized in E.coli and cloned into the plasmid pET28a(+)under optimized expression conditions.CRM197 was purified using Ni-NTA spin columns and ion exchange chromatography,and confirmed by western blot analysis.The puri-fied CRM197 was used to detect specific anti-CRM197 antibody levels in serum samples of different age groups.The results showed that soluble codon-optimized CRM197 was successfully expressed under optimized expression conditions.The purity of CRM197 was more than 95％,as determined with Ni-NTA spin columns and ion exchange chromatography,consistent with the single specific bands obtained by western blot analysis and detection of serum levels of the anti-CRM197 antibody.Collec-tively,these results confirmed that the proposed expression strategy achieved high-yield production of soluble CRM197,al-though high levels in human serum may affect evaluation of immune interactions with glycan-CRM197 conjugates for applica-tion as a diagnostic antigen.The diphtheria mutant toxin CRM197 is used in many conjugate vaccines.The synthetic crm 197 gene with codon optimization in pET28a was transformed into E.coli Origami B(DE3)cells.CRM197 was induced by isopro-pyl β-d-1-thiogalactopyranoside and high level accumulation of soluble CRM197 was purified using Ni-NTA spin columns and ion exchange chromatography.The purity of the final prepara-tion reached 95％.CRM197 was used to detect the concentra-tions of the anti-CRM197 antibody in serum samples of healthy volunteers of different ages.The proposed expression strategy yielded high production of CRM197,which could interfere with evaluations of induced immune interactions by glycan-CRM197 conjugates and prohibit application as a diagnostic antigen.

Objective:To explore the gene mutations of Langerhans cell histiocytosis in children,and to analyze the correlation of BRAF V600E mutation with clinical features and prognosis of LCH,so as to provide reference for clinical diagnosis and treatment. Methods:Fluorescence PCR was used to detect gene mutations in paraffin-embedded tissue samples from 78 children with LCH,and the correlation of BRAF V600E mutation with clinical characteristics and prognosis of LCH in children was analyzed. Results:Among the 78 children,41 cases (52.6％) had BRAF V600E mutation,8 cases (10.3％) had MAP2K1 mutation,1 case (1.3％) had BRAF Exon 12 mutation,1 case (1.3％) had ARAF mutation,and 1 case (1.3％) had PIK3CA mutation. BRAF V600E mutation was not significantly correlated with sex,age,multisystem involvement,risk-organ involvement,CNS-risk lesions,and early treatment response in children with LCH (P>0.05),and it was also not significantly correlated with the recurrence and event-free survival (EFS) of children with LCH (P>0.05). Conclusion:LCH is an inflammatory myeloid tumor. BRAF V600E mutation is not correlated with clinical features,early treatment response,recurrence and prognosis of LCH.

Objective To develop a portable collection device of human exhaled breath condensate(EBC)based on natural breathing to meet the needs for rapid screening of human respiratory tract(especially lower respiratory tract)infections.Methods The device consisted of a refrigeration unit,a heat dissipation unit and a condensation unit.The refrigeration unit adopted a TES1-7102 thermoelectric Peltier cooler semiconductor as the refrigeration element;the heat dissipation unit was composed of a high thermal conductivity aluminum heat sink and a high-speed brushless cooling fan;the condensation unit was made up of a cold guide plate and a condenser,in which the cold guide plate was made of thin sheet of aluminum alloy,and the condenser was prepared by 3D printing technology and made of hydrophobic polylactic acid,with primary and secondary 2-stage guide grooves and an ultra-thin condensing surface.The performance of the device was verified in terms of cooling,thermal conductivity,condensation and human EBC collection and content analysis.Results Performance analysis showed that after refrigeration began the temperature difference between the condenser surface and the exhaled gas met the requirements of the condenser,and no obvious thermal resistance was found on the condensing surface so that large droplets could be formed rapidly and then be collected after the gas-liquid phase change of the exhaled gas on the condensing surface.Human EBC collection and content analysis indicated the device realized home self-collection of EBCs from people of all ages,and the concentrations of interleukins,C-reactive protein and other inflammation-related indexes and the pH value of the collected EBC samples were all correlated with respiratory infections in the subjects.Conclusion The device developed with easy operation avoids the discomfort of blowing collection and the risk of saliva contamination,and is worthy promoting for rapid diagnosis and dynamic monitoring of respiratory tract infection and other related diseases.[Chinese Medical Equipment Journal,2024,45(8):32-37]

One patient was admitted to a hospital due to"sepsis,chronic kidney disease,type 2 diabetes,shock,and cerebral infarction".Patient's blood specimen was taken for clinical examination.Aerobic and anaerobic culture results of catheter blood and venous blood were both positive.The pathogen was identified as Staphylococcus pas-teuri by VITEK MS,and the patient was diagnosed as catheter-related bloodstream infection caused by Staphylo-coccus pasteuri.Clinical empirical use of piperacillin for anti-infection treatment was ineffective,and vancomycin was eventually used for treatment based on in vitro antimicrobial susceptibility testing.Patient's condition improved after removing the venous catheter.There are currently no reported cases of Staphylococcus pasteuri in China.Ear-ly identification of pathogen and adjustment of treatment plans based on antimicrobial susceptibility testing results are crucial for effective treatment of this case.

BACKGROUND:Clinical skin wound healing continues to be a significant concern,and tissue repair research has moved to the forefront with the development of biomaterials with immunomodulatory properties.Therefore,it is crucial to research wound dressings that have immunomodulatory properties. OBJECTIVE:To prepare chitosan hydrogels that have been modified by arginine with different configurations and assess their capacity to speed up wound healing in a rat animal model. METHODS:(1)In vitro trial:Chitosan modified by pure L-arginine,pure D-arginine,and L-arginine and D-arginine was synthesized by EDC/NHS system,which was then crosslinked with aldehyde-modified four-arm polyethylene glycol.Different chitosan-based hydrogels(CS-L,CS-D,and CS-DL)were finally formed via the Schiff base reaction.Three kinds of hydrogel extracts were co-cultured with fibroblasts respectively.Hydrogel cytocompatibility was assessed using the CCK-8 assay and live/dead staining.The effect of hydrogel on the migration capacity of fibroblasts was assessed by using a scratch test.Three kinds of hydrogels were incubated with rat erythrocyte suspension respectively to evaluate the hemocompatibility of the hydrogels.The hydrogel extract was co-cultured with RAW264.7 macrophages to test the hydrogels'capacity to enhance macrophage NO generation and polarize macrophage phenotype.(2)In vivo experiment:A total of 36 adult SD rats were divided into 4 groups with 9 rats in each group by the random number table method.Two full-layer skin defect wounds of 2 cm×2 cm were made on the back of each rat.Normal saline was added to the wounds of the control group,and corresponding hydrogel was added to the wounds of the CS-L,CS-D,and CS-DL groups,respectively,and then bandaged and fixed.The wound healing was observed regularly after operation.Hematoxylin-eosin staining was performed at 3,10,and 21 days after operation.The samples were collected 10 days after operation and M2 macrophage immunofluorescence staining was performed. RESULTS AND CONCLUSION:(1)In vitro experiments:Under scanning electron microscopy,the three kinds of hydrogels exhibited obvious interpenetrating network structures with pore sizes ranging from 70-200 μm.The three kinds of hydrogels have good swelling performance,degradation performance,self-healing performance,and suitable mechanical strength.The three kinds of hydrogels had good cytocompatibility and hemocompatibility and could promote the migration of fibroblasts.All three kinds of hydrogels had the ability to promote the polarization of macrophages,and CS-D hydrogels had the strongest ability to promote the polarization of macrophages.CS-L hydrogel could significantly promote the production of NO in macrophages.(2)In vivo experiment:3 and 10 days after operation,the wound healing rate in the CS-L and CS-D groups was higher than that in the control group(P<0.05).After 21 days,the wound healing rate of the three hydrogel groups was higher than that of the control group.Hematoxylin-eosin staining displayed that a large number of inflammatory cells were infiltrated in the wound tissue of rats in all groups,accompanied by neovessels and fibroblasts 3 days after operation.10 days after operation,there was still more inflammatory cell infiltration in the wound of the control group,and the inflammation of the other three groups was improved,especially the decrease of inflammatory cells in the CS-D group was more obvious.21 days after operation,the wound epithelium of each group was well repaired,and there was basically no inflammatory cell infiltration in the CS-L and CS-D groups,while there was still a small amount of inflammatory cell infiltration in the control group.Immunofluorescence staining revealed that the number of M2-type macrophages in the CS-D group was higher than that in the other three groups(P<0.05).(3)The results conclude that chitosan hydrogels modified by different configurations of arginine can promote wound healing through different mechanisms.

Objective:To investigate the value of antioxidant-associated long non-coding RNAs(lncRNAs)risk score model in prognosis and the association with immune microenvironment of the gastric cancer patients.Methods:Gastric cancer transcriptome data and clinical information were downloaded from TCGA database.Antioxidant-associated lncRNAs were obtained by co-ex-pression analysis of lncRNAs and antioxidant genes.Risk score was constructed using univariate cox regression analysis and lasso regression analysis.Log-Rank test was used to compare the survival differences between two groups.Receiver operating characteristic curve(ROC)was used to assess the specificity and sensitivity of the prognostic risk score model.Nomogram was constructed com-bining risk score and clinical parameters.Immune cell infiltration was assessed by TIMER 2.0.Im-munotherapy sensitivity of each sample was analyzed at TIDE website.Results:A risk score in-cluding 12 IncRNAs was constructed by univariate cox regression analysis and lasso regression anal-ysis.The risk score was an independent factor influencing patient prognosis[HR=5.406(3.131～9.335),P＜0.001].Risk score was positively correlated with multiple suppressive immune cells infil-tration(M2 macrophage,tumor-associated fibroblast).Meanwhile,multiple aberrant expression of immune checkpoint genes and higher TIDE score were found in high-risk group,suggesting that high-risk groups may be more sensitive to immunotherapy.Conclusion:The antioxidant-associ-ated IncRNAs risk score is a good prognostic predictor and can act as a reference in individualized immunotherapy for gastric cancer patients.

Objective To observe the efficacy and safety of Morinda officinalis oligosaccharides in the continuation treatment of mild and moderate depression.Methods An open,single-arm,multi-center design was adopted in our study.Adult patients with mild and moderate depression who had received acute treatment of Morinda officinalis oligosaccharides were enrolled and continue to receive Morinda officinalis oligosaccharides capsules for 24 weeks,the dose remained unchanged during continuation treatment.The remission rate,recurrence rate,recurrence time,and the change from baseline to endpoint of Hamilton Depression Scale(HAMD),Hamilton Anxiety Scale(HAMA),Clinical Global Impression-Severity(CGI-S)and Arizona Sexual Experience Scale(ASEX)were evaluated.The incidence of treatment-related adverse events was reported.Results The scores of HAMD-17 at baseline and after treatment were 6.60±1.87 and 5.85±4.18,scores of HAMA were 6.36±3.02 and 4.93±3.09,scores of CGI-S were 1.49±0.56 and 1.29±0.81,scores of ASEX were 15.92±4.72 and 15.57±5.26,with significant difference(P＜0.05).After continuation treatment,the remission rate was 54.59％(202 cases/370 cases),and the recurrence rate was 6.49％(24 cases/370 cases),the recurrence time was(64.67±42.47)days.The incidence of treatment-related adverse events was 15.35％(64 cases/417 cases).Conclusion Morinda officinalis oligosaccharides capsules can be effectively used for the continuation treatment of mild and moderate depression,and are well tolerated and safe.

Radiation mainly comes from medical radiation,industrial radiation,nuclear waste and atmospheric ultraviolet radiation,etc.,radiation is divided into ionizing radiation and non-ionizing radiation.Studying the effects of ionizing and non-ionizing radiation on drug metabolism,understanding the absorption and distribution of drugs in the body after radiation and the speed of elimination under radiation conditions can provide reasonable guidance for clinical medication.This article reviews the effects of radiation on the pharmacokinetics of different drugs,elaborates the changes of different pharmacokinetics under radiation state,and discusses the reasons for the changes.

Objective To explore the molecular mechanism of Gualou Guizhi decoction which regulates the interferon regulator factor 5(IRF5)signaling pathway to inhibit M1 type microglia activation and reduce the inflammatory response to protect damaged nerve cells.Methods Microglia(BV2)cells were randomly divided into BV2-control,BV2-model,BV2-experimental-L,-M,-H groups.The BV2-control group was given routine culture;the BV2-model group used 100 ng·mL-1 lipopolysaccharide(LPS)to stimulate BV2 which establish an inflammatory model;the BV2-experimental-L,-M,-H groups were cultured in 50,100,200 μg·mL-1 GLGZD and 100 ng·mL-1 LPS.The HT22 cells were divided into the HT-22-blank group,HT-22-model group,HT-22-control group and HT-22 experimental group.HT-22-blank group were conventional culture;HT-22-model group were oxygen glucose deprivation was performed for 2 h,then the complete medium was replaced for 24 h;HT-22-control group were after 2 h of oxygen glucose deprivation,the 100 ng·mL-1 LPS conditioned medium was replaced and incubated for 24 h;HT-22-experimental group were after 2 h of oxygen glucose deprivation,the 200 μg·mL-1 GLGZD conditioned medium was added for 24 h.Interleukin-12(IL-12)and IL-23 were detected by enzyme-linked immunosorbent assay(ELISA);the protein of IRF5,cluster differentiation 16(CD1 6)and MHC class Ⅱ(MHC-Ⅱ)was detected by Western blot;the expression of the synaptic marker protein class Ⅲ β-Tubulin(Tuj-1)was observed by immunofluorescence.Results IL-12 contents in the BV2-control,BV2-model and BV2-experimental-L,-M,-H groups were(2.62±1.02),(10.67±3.22),(6.87±1.61),(3.96±1.22)and(3.36±1.04)pg·mL-1;IL-23 contents were(20.40±2.04),(77.08±3.25),(76.28±3.75),(63.96±4.94)and(54.48±3.34)pg·mL-1;relative expression levels of IRF5 protein were 0.80±0.41,2.22±0.69,1.11±0.11,0.92±0.39 and 0.65±0.29;relative expression levels of CD16 protein were 0.69±0.45,1.91±0.52,1.42±0.22,1.04±0.15 and 0.67±0.30;relative expression levels of MHC-Ⅱ protein were 0.89±0.27,1.96±0.19,1.34±0.38,1.15±0.19 and 0.68±0.24.BV2-experimental-M,-H groups were compared with the BV2-model group,the differences were statistically significant(all P＜0.05).The Tuj-1 protein expression levels were 28.85±6.69,14.44±1.98,7.75±1.12 and 20.05±3.54,determined in the HT22-blank,HT22-model,HT22-control and HT22-experimental groups.The HT22-experimental group was compared with the HT22-control group,the difference was statistically significant(P＜0.05).Conclusion GLGZD may reduces the activation of microglia M1 phenotype through IRF5 signaling pathway,and then inhibits inflammatory response to protect damaged nerve cells.