Objective To investigate the dosimetric effects of different calculation grid size(CGS)in helical tomotherapy(HT)planning system on stereotactic body radiation therapy(SBRT)for non-small cell lung cancer(NSCLC).Methods Nine NSCLC patients receiving radiation therapy for the first time at some hospital from March 2019 to December 2022 were selected as the subjects.SBRT planning was carried out through the HT system with three different CGS plans(Fine,Normal,and Coarse)and the same pitch,modulation factor(MF)and optimization conditions,and the target area indexes of the three CGS plans were compared including conformity index(CI),homogeneity index(HI),dosimetric parameters of the organ at risk(OAR),point dose verification pass rate,treatment time,number of monitor units and Sinograms.SPSS 22.0 was used for statistical analysis.Results For target area HI,there weres significant differences between CGS Fine plan and Coarse plan and between CGS Normal plan and Coarse plan(P＜0.05),while no statistical differences were found between CGS Fine plan and Normal plan(P＞0.05).For target area CI,there were significant differences between CGS Fine plan and Coarse plan(P＜0.05),while no statistical differences were found between CGS Fine plan and Normal plan and between CGS Normal plan and Coarse plan(P＞0.05).For OAR dosimetric parameters,CGS Fine plan and Coarse plan had significant differences in heart Dmax and Dmean,esophageal Dmax and Dmean,V5,V20,V30 and Dmean of the whole lung and affected lung,V5 and Dmax of the affected lung and heart V10 and V30(P＜0.05),CGS Normal plan and Coarse plan had obvious differences in esophageal Dmax(P＜0.05),and the remained dosimetric parameters were not statistically significant(P＞0.05).Fine,Normal and Coarse plans had the point dose verifica-tion pass rates being 0.96％,1.50％and 1.77％,respectively.In terms of treatment time and number of monitor units,there were significant differences between Fine plan and Coarse plan(P＜0.05)while no statistical differences were found between Fine and Normal plans and between Normal and Coarse plans(P＞0.05).Sinograms analyses showed Fine plan had evenly distributed segment color gradient,Coarse plan had areas of very dark and very light color gradients and Normal plan was somewhere in between.Conclusion Low CGS has to be used as much as possible to obtain accurate dose distribution during SBRT planning for NSCLC patients,which contributes to the execution of the radiation therapy plan and the prevention of ad-verse effects.[Chinese Medical Equipment Journal,2024,45(2):52-57]

Objective To investigate the radiotherapy dose impacts of different jaw widths on stereotactic body radiotherapy(SBRT)for hepatocellular carcinoma(HCC)with the hilical tomotherapy(HT)planning system.Methods Totally 16 HCC patients who received radiotherapy at some hospital from March 2021 to August 2023 were selected,and the planning was carried out with the same pitch,modulation factors and optimization conditions and the jaw widths being 1.0,2.5 and 5.0 cm.The dosimetric differences due to the jaw widths in planned targets and organs at risk(OAR)were compared,and the planned treatment time,monitor unit,gantry rotations and gantry period were evaluated.SPSS 22.0 was used for statistical analysis.Results Better dosimetric parameters and lower doses to OARs could be got with lower jaw widths.The widened jaw widths resulted in reduced planned treatment time,decreased monitor units and gantry rotations,shortened gantry period while enhanced treatment efficiency.Conclusion A 2.5 cm jaw width for HT planning contributes to improving treatment efficiency during HCC SBRT under the premise of ensured target dose distribution and satisfactory dose to OAR for clinical require-ments.[Chinese Medical Equipment Journal,2024,45(7):51-55]

Objective To propose an effective method for the determination of 2-chloroethanol(ethylene chlorohydrin,ECH)and ethylene glycol(EG)residues in disposable infusion sets sterilized by ethylene oxide(EO).Methods Extraction with the ratio of the mass of the disposable infusion set to the volume of the medium being 0.4 g/mL was carried out with the 8890B gas chromatograph with liquid injection,DB-WAX column and ethanol extraction medium,and quantitative determination of ECH and EG in disposable infusion sets were implemented after extraction at 37℃for 10 h.Results The method proposely was highly specific,and showed high linearity in the range of 1.25-100.00 μg/mL for both ECH and EG.The limits of detection were 0.31 and 0.11 μg/mL for ECH and EG,respectively,and the relative standard deviations(RSD)of the precision of ECH was in the range of 0.24％-2.03％and those of EG was in the range of 0.16％-0.87％.The average recoveries were 95.02％-100.58％for ECH and 99.15％-99.98％for EG.Conclusion The method proposed for the determination of ECH and EG residues gains advantages in easy operation,specificity,detection accuracy and reproducibility,and meets the requirements for the determination of ECH and EG residues in EO-sterilized disposable infusion sets.[Chinese Medical Equipment Journal,2024,45(10):31-36]

Objective To develop nurses'knowledge,attitude and practice questionnaire on medication management for patients with dysphagia,and test its reliability and validity.Methods Based on the evidence-based summary of the best evidence of medication management for patients with dysphagia,guided by the the-ory of knowledge,attitude and practice,the basic dimensions and item pool of the questionnaire were deter-mined through group discussion,Delphi expert consultation and pre-investigation.In order to revise the ques-tionnaire,437 nurses from 10 tertiary hospitals in Jiangsu Province were conveniently selected for investigation,and the reliability and validity of the questionnaire were tested according to the survey results.Results The nurses'knowl-edge,attitude and practice questionnaire on medication management for patients with dysphagia included 43 items in three dimensions.The three dimensions were analyzed by exploratory factors,and six common factors with characteristic roots>1 were extracted.Two factors were extracted from the knowledge dimension,and the cumulative variance contribution rate was 74.958%,One factor was extracted from the attitude dimen-sion,and the cumulative variance contribution rate was 77.655%.Three factors were extracted from the prac-tice dimension,and the cumulative variance contribution rate was 72.274%.The factor load of each item was 0.618-0.902,Cronbach's α coefficient of the total questionnaire was 0.949,and the test-retest reliability was 0.909.The overall content validity coefficient of the questionnaire was 0.922,and the content validity coeffi-cient for each item was 0.800-1.000.Conclusion The nurses'knowledge,attitude and practice questionnaire on medication management for patients with dysphagia developed in this study has good reliability and validi-ty,and could be used as an effective tool to evaluate the status quo of nurses'medication management for pa-tients with dysphagia.

Objective To establish a stable and reliable method for the determination of ethylene oxide residue,and to analyze ethylene oxide residue in multi components made of different materials involved in some medical devices,so as to provide references for sample selection and ethylene oxide residue detection of multi-component medical device kits.Methods A method for the determination of ethylene oxide residue of multi-component medical devices was developed using headspace-gas chromatography and DB-WAX column under the conditions of headspace extraction with equilibration at 80℃ for 20 min,and the weighing mass,linearity,limit of detection,limit of quantification,precision and recovery of the method were determined.Trials of the method were carried out on the items undergoing ethylene oxide sterilization,including disposable perineal care kit,disposable gynecological examination kit,disposable suture dressing kit,disposable debridement kit and the components contacting human body in the disposable dialysis kit,and the abilities of different materials of the components were analyzed in absorbing,retaining and releasing ethylene oxide.Results The method showed high linearity(r=0.999 8)in the range of ethylene oxide mass concentration from 0.4 to 16.0 μg/mL with a weighing mass of 1.00 g,which had the limit of detection being 0.11 μg/mL,the limit of quantification being 0.37 μg/mL and the relative standard deviations(RSDs)for the precision from 0.35％to 1.52％.The average recoveries of different spiked amounts of ethylene oxide in the three blank matrices ranged from 92.68％to 101.42％with the relative standard deviations(RSDs)from 2.46％to 7.59％,which all satisfied the detection requirements.The components made of rubber and acrylonitrile-butadiene-styrene copolymer(ABS)in multi-component medical device kits had the highest ethylene oxide residues,followed by the components made of wood,degreased cotton,polypropylene and polystyrene.Conclusion The method proposed gains advantages in easy operation and high specificity,quantification and reproducibility,which can be used for the determination of ethylene oxide residue in the multi-component medical device kit undergoing ethylene oxide sterilization.References are provided for sample selection of multi-component medical devices.[Chinese Medical Equipment Journal,2024,45(1):56-61]

The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) is widely used for targeted genomic and epigenomic modifications, transcriptional regulation and real-time cell imaging, and has already demonstrated great potential for applications in agriculture, industry and medicine. The promise of the technology depends upon the five intrinsic properties of CRISPR/Cas: targeting, target unwinding, target cutting, target residence, and collateral cleavage. Here, mainly using Streptococcus pyogenes CRISPR/Cas9 as example, we will focus on the target residence of CRISPR/Cas in applications of the CRISPR/Cas technology, summarize the recent progress, and discuss the effect of CRISPR/Cas target binding and residence on DNA double strand break repair pathway choices and the opportunities that CRISPR/Cas target residence presents to optimize the CRISPR/Cas technology.

R-spondin2 (Rspo2) is a member of protein family RSPOs, which can be coupled to receptor 4/5 (leucine-rich repeat-containing g protein-coupled receptor 4/5, LGR4/5), cell surface transmembrane E3 ubiquitin ligase ZNRF3/RNF43 (zinc and ring finger 3/ring finger protein 43), heparan sulfate proteoglycan (heparan sulfate proteoglycans, HSPGs) and the IQ motif (IQ gap 1) containing GTP enzyme activating protein 1, regulating the Wnt/β-catenin signaling pathway, which is the most widely studied signaling pathway and directly related to basic bone biology. Any problem in this pathway may have an impact on bone regulation. In recent years, it has been found that Rspo2 can act on osteoblast, osteoclast and chondrocytes through Wnt/β-catenin, and take part in occureace and development of some bone diseases such as ossification of the posterior longitudinal ligament (OPLL), osteoarthritis (OA) and rheumatoid arthritis (RA), so the study of Rspo2 may become a new therapeutic direction for bone-related diseases. Based on the latest research progress, this paper reviews the structure and main functions of Rspo2, the mechanism of Rspo2 regulating Wnt/β-catenin signaling pathway and its influence on skeletal system, in order to provide new ideas and ways for the prevention and treatment of bone-related diseases.

Objective To investigate the titer stability of the harvest solution of severe acute respiratory syndrome coronavirus2(SARS-CoV-2)at 2 ～ 8 ℃ and the inactivation effect of β-propiolactone inactivator on the virus.Methods Three batches of SARS-CoV-2 harvest solution(batch numbers:202111001,202111002 and 202111003)were stored at 2 ～ 8 ℃ for 12 d and sampled every 3 d(0,3,6,9 and 12 d)for detection of the titers by Karber method;Three batches of virus harvest solution equilibrated overnight at 2 ～ 8 ℃ were inactivated by adding β-propiolactone at a volume fraction of 1∶4 000 and detected for the titers at different inactivation time points(0,0.5,1,1.5,2,3,4,8,16 and 24 h),of which samples inactivated for 8,16 and 24 h were taken for inactivation verification,and samples inactivated for 24 h were observed by transmission electron microscope.Results The titers of SARS-CoV-2 decreased with the prolongation of storage time at 2 ～8 ℃,which showed no obvious decrease during 0 ～ 3 d,while decreased from the initial 7.75,6 and 7.5 lgCCID_(50)/mL to5.75,4.625 and 6.25 lgCCID_(50)/mL on day 12,indicating that the virus activity showed a gradual decrease trend at 2 ～8 ℃；With the inactivation time,the virus titer decreased continuously and could not be detected after inactivation for 3 h.Transmission electron microscope observation showed that the inactivated virus particles were intact and the spike protein was evenly distributed.Conclusion The virulence of SARS-CoV-2 stored at 2 ～ 8 ℃ was unstable,so the subsequent inactivation and purification process should be carried out as soon as possible;The titer of virus could not be detected after3 h of inactivation,which provided a reference for the determination of the inactivation process.

OBJECTIVE: Arsenic (As) and fluoride (F) are two of the most common elements contaminating groundwater resources. A growing number of studies have found that As and F can cause neurotoxicity in infants and children, leading to cognitive, learning, and memory impairments. However, early biomarkers of learning and memory impairment induced by As and/or F remain unclear. In the present study, the mechanisms by which As and/or F cause learning memory impairment are explored at the multi-omics level (microbiome and metabolome). METHODS: We stablished an SD rats model exposed to arsenic and/or fluoride from intrauterine to adult period. RESULTS: Arsenic and/fluoride exposed groups showed reduced neurobehavioral performance and lesions in the hippocampal CA1 region. 16S rRNA gene sequencing revealed that As and/or F exposure significantly altered the composition and diversity of the gut microbiome，featuring the Lachnospiraceae_NK4A136_group, Ruminococcus_1, Prevotellaceae_NK3B31_group, [Eubacterium]_xylanophilum_group. Metabolome analysis showed that As and/or F-induced learning and memory impairment may be related to tryptophan, lipoic acid, glutamate, gamma-aminobutyric acidergic (GABAergic) synapse, and arachidonic acid (AA) metabolism. The gut microbiota, metabolites, and learning memory indicators were significantly correlated. CONCLUSION Learning memory impairment triggered by As and/or F exposure may be mediated by different gut microbes and their associated metabolites.
Rats ; Animals ; Arsenic/toxicity* ; Fluorides ; RNA, Ribosomal, 16S/genetics* ; Rats, Sprague-Dawley ; Metabolome ; Microbiota

Objective: To explore the pathogenic mechanism of the miR-340/high mobility group box 1 (HMGB1) axis in the formation of liver fibrosis. Methods: A rat liver fibrosis model was established by injecting CCl(4) intraperitoneally. miRNAs targeting and validating HMGB1 were selected with gene microarrays after screening the differentially expressed miRNAs in rats with normal and hepatic fibrosis. The effect of miRNA expressional changes on HMGB1 levels was detected by qPCR. Dual luciferase gene reporter assays (LUC) was used to verify the targeting relationship between miR-340 and HMGB1. The proliferative activity of the hepatic stellate cell line HSC-T6 was detected by thiazolyl blue tetrazolium bromide (MTT) assay after co-transfection of miRNA mimics and HMGB1 overexpression vector, and the expression of extracellular matrix (ECM) proteins type I collagen and α-smooth muscle actin (SMA) was detected by western blot. Statistical analysis was performed by analysis of variance and the LSD-t test. Results: Hematoxylin-eosin and Masson staining results showed that the rat model of liver fibrosis was successfully established. Gene microarray analysis and bioinformatics prediction had detected eight miRNAs possibly targeting HMGB1, and animal model validation had detected miR-340. qPCR detection results showed that miR-340 had inhibited the expression of HMGB1, and a luciferase complementation assay suggested that miR-340 had targeted HMGB1. Functional experiments results showed that HMGB1 overexpression had enhanced cell proliferation activity and the expression of type I collagen and α-SMA, while miR-340 mimics had not only inhibited cell proliferation activity and the expression of HMGB1, type I collagen, and α-SMA, but also partially reversed the promoting effect of HMGB1 on cell proliferation and ECM synthesis. Conclusion: miR-340 targets HMGB1 to inhibit the proliferation and ECM deposition in hepatic stellate cells and plays a protective role during the process of liver fibrosis.
Animals ; Rats ; Cell Proliferation ; Collagen Type I/metabolism* ; Fibrosis ; Hepatic Stellate Cells ; HMGB1 Protein/genetics* ; Liver Cirrhosis/pathology* ; MicroRNAs/metabolism*