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]

Objective To investigate the expressions of 12 cytokines(IL-1β,IL-2,IL-4,IL-5,IL-6,IL-8,IL-10,IL-12p70,IL-17,IFN-α,IFN-γ,TNF-α)and procalcitonin in patients with infective endocarditis(IE).Methods Ten IE patients admitted to our hospital from December 2021 to December 2022 were included into the IE group,10 patients with non-infectious and non-rheumatic valvular diseases who were admitted to our hospital at the same period were randomly selected as the control group,and blood sampling of all patients were conducted at admission.The expressions of 12 cytokines and blood routine indexes were detected by flow cytometry,and the level of procalcitonin was detected by ELISA.The correlations among the expression levels of cytokines in IE patients were analyzed by Pearson method and the correlations of IL-8 level and white blood cell count with procalcitonin in IE patients were analyzed by Spearman method.Results Compared with the control group,the levels of cytokines of IL-1β,IL-2,IL-6,IL-10,TNF-α,IFN-α,IFN-γ and IL-12p70 in the IE group were significantly increased(P<0.05),the white blood cell count,neutrophil percentage and procalcitonin were significantly increased(P<0.05).There was no significant difference in the percentage of monocytes between the two groups(P>0.05).IFN-α of IE patients was positively correlated with IL-2,TNF-α,IL-1β and IL-12p70,IL-2 was positively correlated with TNF-α and IL-1β,IL-12p70 was positively correlated with IFN-γ,and procalcitonin was significantly positively correlated with IL-8 and white blood cell count,with statistically significant differences(P<0.05).Conclusion The levels of IL-1β,IL-2,IL-6,IL-10,TNF-α,IFN-α,IFN-γ,IL-12p70 and procalcitonin in IE patients are significantly higher than those in the normal population,and the detections of these indicators are of guiding significance for the early diagnosis of IE and the evaluation of the severity of the disease.

Objective To analyze the changes of B lymphocyte(B cells)subsets in peripheral blood of patients with chronic hepatitis B(CHB)and to explore its clinical significance.Methods Peripheral blood samples were collected from 37 treatment-na?ve CHB patients who were admitted to the Fifth Medical Center of PLA General Hospital from July 2022 to October 2022,and peripheral blood samples collected from 18 healthy individuals who have received the hepatitis B vaccine as healthy controls(HC).The study subjects'clinical indexes such as age,HBV DNA viral load,HBsAg quantification,HBeAg semi quantification,ALT,AST,and AST/ALT ratio were collected.The change characteristics of the frequency,phenotypic and functional markers of peripheral blood B lymphocytes and their subsets were compared between CHB and HC.Using multi-color flow cytometry,and the correlation between them and clinical indexes was analyzed.Results Frequency analysis of each subset of B cells showed that compared with HC,the frequency of total B cells,transitional B cells and naive B cells was decreased(P<0.05),while the frequency of mature B cells,memory B cells,atypical memory B cells and activated memory B cells was increased in CHB patients(P<0.01).And there was no significant difference in the frequency of resting memory B cells between the two groups(P>0.05).The results of functional analysis showed that compared with HC,the expression levels of CD79b on total B cells,mature B cells,memory B cells,naive B cells,activated memory B cells,atypical memory B cells and resting memory B cells in CHB patients were increased(P<0.05).The expression level of programmed cell death protein-1(PD-1)on atypical memory B cells in CHB patients was also higher than that in HC group(P<0.05).The results of correlation analysis showed that the frequency of total B cells in CHB patients was slightly negatively correlated with age(r=-0.39,P<0.05),while the expression of programmed death-1(PD-1)on total B cells,mature B cells,transitional B cells,memory B cells and naive B cells were slightly positively correlated with age(r>0.36,P<0.05).Conclusions Chronic HBV infection leads to depletion of the frequency and function of a portion of B cells in the peripheral blood of CHB patients,and age is a potential risk factor for the decline in humoral immune function in CHB patients.

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.

ObjectivesBased on the changes of lung lesions in patients with COVID-19 at different stages， a nomogram model describing CT image features was established by radiomics method to explore its efficacy in predicting the progression of the disease. MethodsThis retrospective study enrolled 136 patients with COVID-19 pneumonia who received at least two CTs including three cohorts （training cohort and validation cohort 1 and 2）. Patients in the training cohort were divided into three groups according to time between onset of fever symptoms and the first CT. The clinical manifestations and CT features of each group were analyzed and compared. A nomogram to predict disease progression was constructed according to the CT features of the patients， and its performance was evaluated. ResultsThe training cohort consisted of 41 patients.A nomogram was generated to predict disease progression based on three CT features： irregular strip shadow， air bronchial sign， and the proportion of lesions with irregular shape ≥50%. AUC（95%CI）=0.906（0.817，0.995）.The C index of the training cohort was 0.906， and the C index of the internal verification was 0.892. AUC（95%CI）of the validation cohort 1 （34 cases） =0.889（0.793，0.984）；AUC（95%CI）of the validation cohort 2 （61 cases）=0.876（0.706，1.000）.The calibration curves show that the predicted values of the nomogram are in good agreement with the observed values. ConclusionThe nomogram model based on CT radiomics can predict the outcome of lung lesions in patients with high sensitivity and specificity.According to the changes of CT image characteristics of patients with COVID-19， lung lesions will be improved when the proportion of irregular cable shadow， air bronchogram and irregular lesions is greater than 50%.

AIM: To investigate the bacterial flora and antibiotic susceptibility testing of conjunctival sac in adolescents after wearing orthokeratology(OK)lens.METHODS:A total of 101 adolescents aged 8 to 14 who admitted to outpatient department of Xi'an No.1 Hospital from September 2021 to August 2022 were recruited in this cross-sectional observational study. There were 51 cases wearing OK Lens(wearing group)and 50 patients not wearing contact lens(non-lens group), the right eye of all patients was selected into the group. The culture of bacterial flora in conjunctival sac between the two groups were compared, the species were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and the antibiotic susceptibility testing was carried out for the positive strains cultured in the wearing group.RESULTS:The positive rate of conjunctival sac bacterial cultured in the wearing group and the non-lens group was 68.6%(35/51)and 60.0%(30/50), respectively(P>0.05). In both groups, the bacteria with the highest detection rate were staphylococcus epidermidis and staphylococcus aureus. The sensitivity rates of the strains detected in the wearing group to drugs are as follows: Levofloxacin(98%), Moxifloxacin(98%), Gatifloxacin(98%), Cefuroxime(98%), Cefathiamidine(98%), Rifampicin(98%), Chloramphenicol(96%), Cefoxitin(95%), Clindamycin(80%), Gentamicin(74%), Fusidic acid(72%), Tobramycin(64%), Compound sulfamethoxazole(26%), Mezlocillin(10%), Azithromycin(6%), of which the sensitivity rate of Gram-positive cocci was 100% sensitive to Vancomycin.CONCLUSION:Gram-positive cocci are the main bacteria isolated from conjunctival sac of adolescents after wearing OK Lens. Wearing OK Lens will not significantly increase the positive rate of conjunctival sac bacterial flora. Results of antibiotic susceptibility testing may provide guidance for empirical medication in patients wearing OK lens after eye infection.

The present article was aimed to compare the effectiveness of different induction methods for depression models. Kunming mice were randomly divided into chronic unpredictable mild stress (CUMS) group, corticosterone (CORT) group, and CUMS+CORT (CC) group. The CUMS group received CUMS stimulation for 4 weeks, and the CORT group received subcutaneous injection of 20 mg/kg CORT into the groin every day for 3 weeks. The CC group received both CUMS stimulation and CORT administration. Each group was assigned a control group. After modeling, forced swimming test (FST), tail suspension test (TST) and sucrose preference test (SPT) were used to detect the behavioral changes of mice, and the serum levels of brain-derived neurotrophic factor (BDNF), 5-hydroxytryptamine (5-HT) and CORT were detected with ELISA kits. Attenuated total refraction (ATR) spectra of mouse serum were collected and analyzed. HE staining was used to detect morphological changes in mouse brain tissue. The results showed that the weight of model mice from the CUMS and CC groups decreased significantly. There was no significant change in immobility time of model mice from the three groups in FST and TST, while the glucose preference of model mice from the CUMS and CC groups was significantly reduced (P < 0.05). The serum 5-HT levels of model mice from the CORT and CC groups were significantly reduced, while the serum BDNF and CORT levels of model mice from the CUMS, CORT, and CC groups showed no significant changes. Compared with their respective control groups, the three groups showed no significant difference in the one-dimensional spectrum of serum ATR. The difference spectrum analysis results of the first derivative of the spectrogram showed that the CORT group had the greatest difference from its respective control group, followed by the CUMS group. The structures of hippocampus in the model mice from the three groups were all destroyed. These results suggest that both CORT and CC treatments can successfully construct a depression model, and the CORT model is more effective than the CC model. Therefore, CORT induction can be used to establish a depression model in Kunming mice.
Mice ; Animals ; Depression/etiology* ; Antidepressive Agents/pharmacology* ; Brain-Derived Neurotrophic Factor ; Serotonin

Objective: To understand the current situation regarding pediatric off-label use of drugs recommendations in Chinese clinical practice guidelines and to make recommendations for standardized reporting format regarding off-label use of drugs for children. Methods: This cross-sectional study was carried out by systematically searching the databases for Chinese guideline consensus articles published in journals between 2018 and 2020 and extracting recommendations regarding off-label use of drugs from those articles. The essential characteristics of the included guidelines, the ranking of off-label drug types, the order of drug information, the type of off-label drug use, and the percentage of citation studies on which the recommendations were based were analyzed. Results: Among 108 studies that included Chinese off-label guidelines and consensus, 364 recommendations on pediatric off-label use of drugs were included. The Chinese Medical Association published the most, 48 out of the 108 studies (44.4%), and of those 14 studies (13.0%) were on infectious and parasitic diseases. Of the 364 recommendations on off-label use of drugs, the most commonly addressed drugs were 16 recommendations (4.4%) for cyclosporine A, 11 recommendations (3.0%) for methotrexate , and 11 recommendations (3.0%) for fentanyl. The most commonly addressed drug categories were as follows: 68 recommendations (18.6%) were immune system drugs, 66 recommendations (18.1%) were anti-infectives, and 56 recommendations (15.4%) were oncology drugs. The most commonly addressed drug information accounts were as follows: 364 recommendations (100.0%) were indications, 204 recommendations (56.0%) were dosages, and 198 recommendations (54.4%) were the route of administration. Based on the instructions approved by the Chinese Food and Drug Administration, the main forms of the off-label drug were as follows: 175 recommendations (48.1%) were unapproved indications, 127 recommendations (34.9%) were unapproved populations, and 72 recommendations (19.8%) were unapproved ages. Only 129 recommendations (35.4%) were cited, mainly including clinical guidelines (48 studies, 23.4%), reviews (22 studies, 10.7%), and pediatric randomized controlled trials (22 studies, 10.7%). Conclusions: Off-label use of drugs is commonly recommended in pediatric guidelines and consensus documents written by Chinese authors. However, the reporting of the recommendations varies widely, and the quality of the supporting evidence is poor.
Child ; China ; Consensus ; Cross-Sectional Studies ; Humans ; Off-Label Use ; Pharmaceutical Preparations

OBJECTIVE: To investigate the roles of angiotensin-converting enzyme 2 (ACE2) in ozone-induced pulmonary inflammation and airway remodeling in mice. METHODS: Sixteen wild-type (WT) C57BL/6J mice and 16 ACE2 knock-out (KO) mice were exposed to either filtered air or ozone (0.8 ppm) for 3 h per day for 5 consecutive days. Masson's staining and HE staining were used to observe lung pathologies. Bronchoalveolar lavage fluid (BALF) was collected and the total cell count was determined. The total proteins and cytokines in BALF were determined by BCA and ELISA method. The transcription levels of airway remodeling-related indicators in the lung tissues were detected using real-time quantitative PCR. The airway resistance of the mice was measured using a small animal ventilator with methacholine stimulation. RESULTS: Following ozoneexposure ACE2 KO mice had significantly higher lung pathological scores than WT mice (P < 0.05). Masson staining results showed that compared with ozone-exposed WT mice, ozone-exposed ACE2 KO mice presented with significantly larger area of collagen deposition in the bronchi [(19.62±3.16)% vs (6.49±1.34)%, P < 0.05] and alveoli [(21.63±3.78)% vs (4.44±0.99)%, P < 0.05]. The total cell count and total protein contents in the BALF were both higher in ozone-exposed ACE2 KO mice than in WT mice, but these differences were not statistically significant (P > 0.05). The concentrations of IL-6, IL-1β, TNF-α, CXCL1/KC and MCP-1 in the BALF were all higher in ozone-exposed ACE2 KO mice than in ozone-exposed WT mice, but only the difference in IL-1β was statistically significant (P < 0.05). The transcription levels of MMP-9, MMP-13, TIMP 4, COL1A1, and TGF-β in the lung tissues were all significantly higher in ozone-exposed ACE2 KO mice (P < 0.01). No significant difference was found in airway resistance between ozone-exposed ACE KO mice and WT mice after challenge with 0, 10, 25, or 100 mg/mL of methacholine. CONCLUSION ACE2 participates in ozone-induced lung inflammation and airway remodeling in mice.
Airway Remodeling ; Angiotensin-Converting Enzyme 2 ; Animals ; Methacholine Chloride ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Ozone/adverse effects* ; Pneumonia

Chronic psychological stress can promote vascular diseases, such as hypertension and atherosclerosis. This study aims to explore the effects and mechanism of chronic psychological stress on aortic medial calcification (AMC). Rat arterial calcification model was established by nicotine gavage in combination with vitamin D₃ (VitD₃) intramuscular injection, and rat model of chronic psychological stress was induced by humid environment. Aortic calcification in rats was evaluated by using Alizarin red staining, aortic calcium content detection, and alkaline phosphatase (ALP) activity assay. The expression levels of the related proteins, including vascular smooth muscle cells (VSMCs) contractile phenotype marker SM22α, osteoblast-like phenotype marker RUNX2, and endoplasmic reticulum stress (ERS) markers (GRP78 and CHOP), were determined by Western blot. The results showed that chronic psychological stress alone induced AMC in rats, further aggravated AMC induced by nicotine in combination with VitD₃, promoted the osteoblast-like phenotype transformation of VSMCs and aortic ERS activation, and significantly increased the plasma cortisol levels. The 11β-hydroxylase inhibitor metyrapone effectively reduced chronic psychological stress-induced plasma cortisol levels and ameliorated AMC and aortic ERS in chronic psychological stress model rats. Conversely, the glucocorticoid receptor agonist dexamethasone induced AMC, promoted AMC induced by nicotine combined with VitD₃, and further activated aortic ERS. The above effects of dexamethasone could be inhibited by ERS inhibitor 4-phenylbutyrate. These results suggest that chronic psychological stress can lead to the occurrence and development of AMC by promoting glucocorticoid synthesis, which may provide new strategies and targets for the prevention and control of AMC.
Rats ; Animals ; Glucocorticoids/metabolism* ; Rats, Sprague-Dawley ; Nicotine/metabolism* ; Hydrocortisone/metabolism* ; Muscle, Smooth, Vascular ; Dexamethasone/metabolism* ; Vascular Calcification/metabolism* ; Myocytes, Smooth Muscle/metabolism* ; Cells, Cultured