The innate immune system can be boosted in response to subsequent triggers by pre-exposure to microbes or microbial products, known as “trained immunity”. Compared to classical immune memory, innate trained immunity has several different features. Firstly, the molecules involved in trained immunity differ from those involved in classical immune memory. Innate trained immunity mainly involves innate immune cells (e.g., myeloid immune cells, natural killer cells, innate lymphoid cells) and their effector molecules (e.g., pattern recognition receptor (PRR), various cytokines), as well as some kinds of non-immune cells (e.g., microglial cells). Secondly, the increased responsiveness to secondary stimuli during innate trained immunity is not specific to a particular pathogen, but influences epigenetic reprogramming in the cell through signaling pathways, leading to the sustained changes in genes transcriptional process, which ultimately affects cellular physiology without permanent genetic changes (e.g., mutations or recombination). Finally, innate trained immunity relies on an altered functional state of innate immune cells that could persist for weeks to months after initial stimulus removal. An appropriate inducer could induce trained immunity in innate lymphocytes, such as exogenous stimulants (including vaccines) and endogenous stimulants, which was firstly discovered in bone marrow derived immune cells. However, mature bone marrow derived immune cells are short-lived cells, that may not be able to transmit memory phenotypes to their offspring and provide long-term protection. Therefore, trained immunity is more likely to be relied on long-lived cells, such as epithelial stem cells, mesenchymal stromal cells and non-immune cells such as fibroblasts. Epigenetic reprogramming is one of the key molecular mechanisms that induces trained immunity, including DNA modifications, non-coding RNAs, histone modifications and chromatin remodeling. In addition to epigenetic reprogramming, different cellular metabolic pathways are involved in the regulation of innate trained immunity, including aerobic glycolysis, glutamine catabolism, cholesterol metabolism and fatty acid synthesis, through a series of intracellular cascade responses triggered by the recognition of PRR specific ligands. In the view of evolutionary, trained immunity is beneficial in enhancing protection against secondary infections with an induction in the evolutionary protective process against infections. Therefore, innate trained immunity plays an important role in therapy against diseases such as tumors and infections, which has signature therapeutic effects in these diseases. In organ transplantation, trained immunity has been associated with acute rejection, which prolongs the survival of allografts. However, trained immunity is not always protective but pathological in some cases, and dysregulated trained immunity contributes to the development of inflammatory and autoimmune diseases. Trained immunity provides a novel form of immune memory, but when inappropriately activated, may lead to an attack on tissues, causing autoinflammation. In autoimmune diseases such as rheumatoid arthritis and atherosclerosis, trained immunity may lead to enhance inflammation and tissue lesion in diseased regions. In Alzheimer’s disease and Parkinson’s disease, trained immunity may lead to over-activation of microglial cells, triggering neuroinflammation even nerve injury. This paper summarizes the basis and mechanisms of innate trained immunity, including the different cell types involved, the impacts on diseases and the effects as a therapeutic strategy to provide novel ideas for different diseases.

Objective:To compare the application of Micronutritional Risk Assessment(MNA),Universal Screening Tool for Malnutrition(MUST)and Nutritional Risk Screening 2002(NRS2002)in nutritional risk assessment among patients with digestive tract tumors during perichemotherapy,based on the Global Leadership Initiative on Malnutrition(GLIM)standard.Methods:A prospective cross-section study was conducted,including 114 patients with digestive tract tumors hospitalized by Department of General Surgery,Huangshan Shoukang Hospital from January 2020 to December 2021.All patients were evaluated by GLIM assessment,the correlation between GLIM and MNA,MUST and NRS 2002 screening results was compared,and the consistency among different methods was compared.Patients were divided into malnourished group(nutritional risk group)or normal nourished group according to the results of the three tools.The differences in single anthropometric or test indicators between the groups were compared.Results:According to GLIM,the proportion of malnutrition was 36.8%.The proportion of malnutrition evaluated by MNA,MUST,and NRS2002 were 63.2%,47.4%,and 32.5%,respectively.The sensitivity and negative predictive value of MNA in assessing nutrition-related risks were the highest,while the specificity,Jorden index,Kappa value and positive predictive value of NRS2002 were the highest.There were statistical differences in levels of body mass index,hemoglobin(Hb),triglyceride,total cholesterol,albumin,prealbumin(P-ALB),blood creatinine,lymphocyte counts,and hospitalization costs between two groups assessed by three different tools(P<0.05).Levels of Hb and P-ALB were statistically different between the two groups of the three screening tools.Conclusion:Based on GLIM evaluation results,MNA and other nutritional screening tools are applicable to the assessment of nutritional risks of patients with gastrointestinal cancer during perichemotherapy due to the joint evaluation of measurement indicators.The MNA is more recommended with the highest detection rate and sensitivity for nutritional risks assessment.

As a new generation of time-of-flight mass spectrometry,multiple-reflection time-of-flight mass spectrometry(MR-TOF-MS)has been increasingly applied in the fields such as nuclear physics,chemistry,and biology due to its ultra-high resolution and rapid analysis capabilities.However,the analytical performance of MR-TOF-MS largely depends on the ion bunch state entering the mass analyzer.In this study,a rectangular ion trap(RIT)was developed,designed and processed using printed circuit board technology,as an ion accumulating and focusing device for MR-TOF mass analyzer.Compared to traditional ion traps composed of two sets of planar electrodes,this RIT had higher voltage utilization efficiency,resulting in more efficient ion collection and focusing.The ions were cooled to a sufficiently small bunch for precise mass measurement with MR-TOF-MS mass spectrometry in only 1 ms of cooling time in the RIT,then orthogonally ejected to the MR-TOF mass spectrometer for mass analysis.Experimental results indicated that the working cycle,ion flux,and ion focusing state of the RIT fully met the requirements of the MR-TOF mass analyzer.When coupled with the MR-TOF mass analyzer,the RIT enabled MR-TOF-MS to achieve a mass resolution of 1.5×105.

The bottom-up construction of artificial cells to mimic signal transduction is of great significance for a deep understanding of the communication networks of complex living systems.The dynamic coupling of signal secretion and response among artificial cells poses an important challenge.In this work,two types of artificial cells were constructed through a bio-artificial hybrid strategy.One was an artificial cell as an AI-2 signal sender(sender),which contained bacteria capable of autonomously synthesizing AI-2 signaling molecules.The other was an artificial cell as an AI-2 signal receiver(receiver),which contained bacteria expressing green fluorescent protein in response to the corresponding AI-2 signal.When the ratio of senders to receivers was 4∶1,the fluorescent signal of the receivers gradually increased over time and reached a plateau at 240 minutes.The artificial cells capable of sending and receiving quorum sensing signaling molecules constructed in this work laid a foundation for the study of complex signal communication within artificial cell populations.

Decabromodiphenyl ether(BDE-209)and decabromodiphenyl ethane(DBDPE)are widely used brominated flame retardants,which have been detected in the atmosphere,water,soil,and various organisms.In this study,a method based on high-performance liquid chromatography-inductively coupled plasma-mass spectrometry(HPLC-ICP-MS)was developed for determination of BDE-209 and DBDPE in sediment.Firstly,the target compounds in the sediments were extracted by accelerated solvent extraction(ASE),and the extraction solvent was hexane/dichloromethane(1∶1,V/V).The extract was concentrated by rotary evaporation and purified by a composite silica gel column(6 g neutral silica gel,8 g acidic silica gel,and 4 g anhydrous sodium sulfate),concentrated by nitrogen blowing,and then re-dissolved with 1 mL of toluene for instrumental determination.The chromatographic separation was carried out on a TC-C18(2)column(250 mm×4.6 mm)with isocratic elution using methanol-isopropanol-water(89∶6∶5,V/V)as the mobile phase,and the samples were separated within 20 min.Further,the Br element was quantified by ICP-MS to realize the detection of the target.The results showed that the method established in this study exhibited good linearity(R2>0.999)in the range of 100-10000 ng/mL,and the limits of quantification(LOQs)of the method were 2.0 ng/g for BDE-209 and 10.0 ng/g for DBDPE,with the relative standard deviations(RSDs,n=3)lower than 10%,and the recoveries were in the acceptable range(80.9%-120.7%).The matrix effect was effectively controlled within 10%.In addition,by analyzing the actual sediment samples from Guangxi,a background point,and Taizhou,Zhejiang,a typical contaminated area,it was found that neither BDE-209 nor DBDPE was detected in the sediment from Guangxi,while the concentrations of BDE-209 and DBDPE in the sediment from Zhejiang ranged from 1591.8 to 3362.9 ng/g,which further demonstrated the applicability and reliability of the method for analyzing actual environmental samples.This study provided a strong technical support for the accurate detection of POPs in the environment.

The faithful segregation of genetic material to daughter cells is a fundamental biological process and a prerequisite for autonomous construction of robustly self-replicating artificial cells.Artificial cells are mimic cell structures with part or whole functions of normal cells.The complexity of eukaryotic chromosome segregation machinery has limited its applications in the field of synthetic biology.In contrast,the plasmid segregation machineries employed by prokaryotes are relatively simple and can provide valuable approaches for the bottom-up construction of complex artificial cells.This review aimed to comprehensively analyze the origin species and working mechanism of three bacterial plasmid segregation systems,namely ParABS,ParMRC,and TubZRC systems.The current researches on plasmid segregation both in bacterial and artificial cellular systems were summarized,and the future directions of this field were also proposed.

Objective To verify the efficacy of a domestic human DNA quantification kit based on real-time fluorescence quantitative PCR in detecting the total human DNA concentration,male DNA concen-tration in mixed male/female DNA samples,the degree of DNA degradation and inhibitor tolerance.Methods Samples with different concentrations,different male/female ratios,different concentrations of inhibitors,and different degradation degrees were tested using the domestic human DNA quantification kit based on real-time fluorescence quantitative PCR.This kit was compared with a similar product on the market and was applied to the detection of DNA from real cases.Results This human DNA quan-tification kit can effectively detect human DNA as low as 0.001 65 ng/μL,and 6.25 pg/μL of male DNA in mixed samples with a male-to-female ratio of 1∶15 000.Even when the sample contains as high as 400 ng/μL of humic acid or 1 000 μmol/L of hemin alone,the DNA concentration can still be accurately detected.The degradation index can effectively characterize the degradation degree of the sample.This kit has been successfully applied in forensic practice.Conclusion This human DNA quan-tification kit is accurate and reliable in detection.It can accurately reflect the degradation of DNA and inhibitor tolerance.It has good performance in quantitative accuracy,determination of the male/female ratio in mixed samples,and inhibitor tolerance.It has application potential in forensic case examination.

Objective To construct a competency evaluation model for forensic practitioners,providing a reference for their training and assessment.Methods Based on the iceberg and onion models of com-petency,and with reference to Spencer's Competency Dictionary,literature research was conducted and focus group interviews were employed to preliminarily construct core indices and measurement items for evaluating the competency of forensic practitioners.The Delphi method was applied for two rounds of expert consultation to further refine the competency evaluation index system.The analytic hierarchy process(AHP)was used to calculate the weights of the indices.Results A competency evaluation model for forensic practitioners was constructed,consisting of 7 core indices,encompassing forensic skills,identification service capabilities,and the ability to apply relevant legal knowledge and 49 mea-surement items.The weights of the core indices and measurement items were determined.Conclusion The constructed competency evaluation model for forensic practitioners is scientifically sound and inno-vative,and has unique characteristics of forensic medicine compared with other medical models.

Objective To investigate the effects of estrogen signaling on T-cell recruitment and polarization in acutely injured skeletal muscle.Methods One hundred C57BL/6 male mice,one hundred and eighty C57BL/6 female mice were selected.Twenty-five female mice were ovariectomized(OVX)and 10 male mice were taken as the sham-operated(sham).Then,cardiotoxin(CTX)induced tibialis anterior(TA)injury for preparing mice myoinjury model.Subcutaneous injection of 17β-estradiol(E2)or estrogen receptor antagonist 4-hydroxytamoxifen(4-OHT)was performed.A total of 140 mice(70 males and 70 females)were divided into four group including:PBS-male,CTX-male,PBS-female,and CTX-female.Serum estradiol(E2)levels were measured by ELISA,and muscle injury models were validated via HE staining.Subsequently,20 male and 20 female mice were selected for immunofluorescence(IF)and Real-time PCR to assess estrogen receptors(ER)expression in injured muscle tissue.Further,10 male and 40 female mice were allocated into five experimental groups,including CTX,CTX+E2,CTX+4-OHT,CTX+OVX,CTX+sham.HE staining and IF were performed to evaluate inflammatory infiltration in the injured muscle.Additionally,50 female mice were divided into CTX and CTX+OVX groups,and IF combined with flow cytometry were used to analyze T-cell phenotypes and muscle fiber regeneration in the injured muscle.Results In vivo,serum E2 and myofiber ERβ increased post-injury in mice of both sexes,significantly higher in females.Compared to the control group,E2 alleviated inflammation,OVX exacerbated inflammation,increased CD4+T-cell infiltration,elevated T helper 1 cell(Th1)response,decreased regulatory T cells(Tregs),impaired regeneration.In vitro,IFN-γ/LPS significantly upregulated ERβ in myotubes.Conclusion Estrogen signaling critically regulates muscle inflammation.Estrogen deficiency(OVX)delays repair of skeletal muscle by promoting Th1 response and suppressing Tregs function.

Objective To investigate the density,species composition,and seasonal prevalence of domestic rodents in different habitats within Lanzhou garrisons,providing basic information for rodent prevention and control.Methods A total of 12 monitoring sites were sampled across urban,suburban,and rural residential areas from 2014 to 2022.Rodent density was monitored using the night-trapping method in the middle of odd-numbered months.Results From 2014 to 2022,346 domestic rodents were captured using 122 035 effective traps,with an average domestic rodent density of 0.28％.The highest domestic rodent density was 0.63％in 2016,and the lowest was 0.07％in 2020,showing significant differences across years,with an overall trend of initially decreasing and then increasing(χ2=136.555,P<0.001).The dominant species was Rattus norvegicus,accounting for 83.24％of the total rodents captured.Rattus norvegicus accounted for a relatively high proportion across different years,with a statistically significant difference in species composition(χ2=20.931,P<0.05).Rodent densities and species composition also varied significantly among the monitored habitats(P<0.001),with the highest densities observed in rural residential areas and the lowest in urban areas.Seasonal variation in rodent densities showed a bimodal pattern,with smaller peaks in January or March and a larger peak in July.Conclusions Domestic rodent density in Lanzhou garrisons has shown an upward trend in the past few years.Rodent control measures should focus on barracks in rural residential areas,with targeted interventions to reduce the risk of rodent-borne diseases.