1.Mechanism of high glucose-regulated SIRT6 expression affecting the functions of retinal pigment epithelial cells and vascular endothelial cells
Qian ZHANG ; Mingxiu LUO ; Yu GUO ; Feiyang LUO ; Yuan MA ; Qing YAO
International Eye Science 2026;26(10):1698-1709
AIM: To investigate the effects of high-concentration glucose on the cell viability of retinal pigment epithelialcells(ARPE-19)/ human umbilical vein endothelial cells(HUVEC)cells, as well as on the expression levels of sirtuin 6(SIRT6).
METHODS:ARPE-19 and HUVEC cells were cultured for 48 h in media containing various glucose concentrations(5.5, 25, 50, 75, 100 mmol/L)and cellular morphology was observed under an optical microscope.Cell viability was assessed using the CCK-8 assay. Flow cytometry was utilized to evaluate apoptosis levels, and Western blot analysis was conducted to measure the expression of Bcl-2 and SIRT6. ARPE-19/HUVEC cells were treated with 50 mmol/L glucose for 48 h, after which immunofluorescence staining was performed to determine the subcellular localization and expression level of SIRT6 protein. In parallel, cells receiving the same treatment were harvested at different time points(0, 6, 12, 24, 36, 48, and 72 h), and the temporal changes in SIRT6 protein expression were assessed by Western blot analysis. SIRT6 overexpressing stable ARPE-19/HUVEC cell lines were constructed. Western blot was performed to detect the effects of SIRT6 overexpression on the expression levels of glucose transporters in ARPE-19/HUVEC cells treated with high glucose(50 mmol/L glucose).
RESULTS:Compared with the 5.5 mmol/L glucose group, cell number was decreased and cell viability was significantly reduced in ARPE19/HUVEC cells with increasing glucose concentrations(all P<0.01). Meanwhile, the protein expression level of SIRT6 was markedly downregulated(P<0.05). Such inhibitory effects exhibited both concentration-and time-dependent patterns(all P<0.05). Furthermore, high glucose induced cell apoptosis and downregulated the protein expression of Bcl-2(P<0.05). Immunofluorescence staining revealed that SIRT6 protein was predominantly localized in the nucleus after 48 h of high-glucose treatment, accompanied by pyknosis and nuclear fragmentation. After incubation with highg-lucose medium(50 mmol/L glucose)for different durations, long-term high-glucose intervention was found to reduce SIRT6 protein expression in ARPE19/HUVEC cells. Successful construction of the SIRT6-overexpressing stable ARPE-19/HUVEC cell lines was confirmed via immunofluorescence and Western blotting. Western blot analysis revealed that, compared with the HG+LV-con group, the HG+LV-SIRT6 group exhibited no significant differences in GLUT1 or GLUT4 expression in ARPE-19 cells, whereas GLUT3 expression was elevated(P<0.05). Compared with the HG+LV-con group, the HG+LV-SIRT6 group showed no significant change in GLUT1 expression, while GLUT3 and GLUT4 levels were increased(both P<0.05).
CONCLUSION:High-concentration glucose-reduce the proliferative activity of ARPE-19/HUVEC cells, induce apoptosis, and downregulate SIRT6 expression. SIRT6 may alleviate high glucose-induced retinal cell damage by promoting the expression of glucose transporters.
2.Genetic analysis of a family with Ellis-van Creveld syndrome caused by compound heterozygous mutations in the EVC gene:A case report and literature review
Dong-Lan SUN ; Wen-Qi CHEN ; Jing ZHANG ; Yuan-Yuan PENG ; Yu-Fan YUAN ; Zhao-Xi WANG ; Qing GUO ; Jing ZHANG
Medical Journal of Chinese People's Liberation Army 2025;50(2):168-175
Objective To report the genetic analysis of a family with a fetus suspected of Ellis-van Creveld(EVC)syndrome based on ultrasound findings such as ventricular septal defect(VSD),short long bones in the limbs and polydactyly,and to conduct a literature review to clarify the pathogenic cause.Methods A 27-year-old pregnant woman,who was pregnant for the first time and had no prior deliveries,was admitted to the prenatal diagnosis center of Shijiazhuang Obstetrics and Gynecology Hospital in October 2021.At 17 weeks of gestation,ultrasound detected multiple fetal malformations.The genomic DNA of the fetal proband's amniotic fluid cells and the parents'peripheral blood samples were sequentially subjected to chromosomal karyotype analysis,chromosomal microarray analysis(CMA),and whole exome sequencing(WES).Suspected pathogenic mutations were verified by Sanger sequencing in the proband and its parents.Subsequently,a Minigene in vitro experiment was used to analyze one splicing mutation.Meanwhile,databases such as PubMed were searched,and literature reports were combined for genetic analysis.Results Chromosomal karyotype analysis of the fetus showed no abnormalities,and CMA did not detect any copy number variation(CNV)with clinical significance.WES results revealed two mutations in the EVC gene(NM_153717.2)of the fetus:a nonsense mutation c.1405G>T(p.E469X)in exon 10 and a splicing mutation c.1886+5G>A in intron 13.Family verification using Sanger sequencing showed that the father was a carrier of the c.1405G>T(p.E469X)mutation in exon 10,and the mother was a carrier of the c.1886+5G>A mutation in intron 13.The compound heterozygous mutation of the fetus was inherited from the parents.According to the guidelines of the American College of Medical Genetics and Genomics(ACMG)for classifying genetic variations,c.1405G>T(p.E469X)was classified as likely pathogenic mutation(PVS1+PM2),and c.1886+5G>A was classified as likely pathogenic mutation(PM2+PM3_Strong).The Minigene experiment results showed that the c.1886+5G>A mutation caused a 115-bp segment retention in intron 13,further supporting its pathogenicity.Review of the literature showed that the typical clinical manifestations of EVC syndrome include short limbs,short ribs,postaxial polydactyly,nail and tooth dysplasia,and congenital heart defects.Gene mutations in EVC/EVC2 were found to be the main pathogenic cause through whole exome sequencing,with mutation types including missense mutations,large-scale duplications/deletions,in-frame microdeletions,nonsense mutations,frameshift mutations,and splicing mutations.Conclusions The compound heterozygous mutations in the EVC gene are the pathogenic cause of the fetus.The detection of these mutations expands the genetic variation spectrum of Ellis-van Creveld syndrome.
3.Mechanism of senegenin in improving lipopolysacchride-induced inflammatory response of BV2 microglial cell
Bing-Tao MU ; Min-Fang GUO ; Jing-Wen YU ; Jia-Lei CAO ; Feng-Jun YANG ; Si-Wei JIA ; Qing SU ; Tao MENG ; Cun-Gen MA ; Jie-Zhong YU ; Li-Juan SONG
Medical Journal of Chinese People's Liberation Army 2025;50(2):188-196
Objective To investigate the mechanism by which Senegenin(SEN)alleviates microglial inflammatory response through the nuclear factor erythroid 2-related factor 2(Nrf2)/NOD-like receptor protein 3(NLRP3)pathway.Methods BV2 mouse microglia cells were randomly divided into control group,model group,SEN group and MCC950 group.Cells in control group were not treated,and cells in model group were added with 1 μg/ml lipopolysaccharide(LPS);Cells in SEN group were added with 1 μg/ml LPS+4 μmol/L SEN,and cells in MCC950 group were added with 1 μg/ml LPS+10 μmol/L MCC950 for 24 hours.CCK-8 method was used to detect the effect of different concentrations of SEN on the viability of BV2 cells.Griess method was used to determine the release amount of nitric oxide(NO)in the supernatant.Real-time fluorescent quantitative PCR was used to determine the mRNA expression levels of NLRP3,lymphocyte apoptosis-associated spect-like protein containing a CARD(ASC),caspase-1,interleukin(IL)-1β and IL-18 mRNA.Immunofluorescence staining was used to detect the expression levels of ASC,IL-1β,Nrf2 and heme oxygenase-1(HO-1).Western blotting was used to detect the expression levels of NLRP3,caspase-1,ASC,IL-1β,IL-18,Nrf2,HO-1,nuclear factor kappa B(NF-κB)and inducible nitric oxide synthase(iNOS).Results The results of CCK-8 method showed that there was no significant difference in the viability of BV2 cells treated with 2~20 μmol/L SEN compared with control group(P>0.05).Compared with control group,the viability of BV2 cells in model group decreased significantly(P<0.05).Compared with model group,the viability of BV2 cells in 4 μmol/L SEN group was significantly restored(P<0.05).Compared with control group,the results of Griess method showed that the release amount of NO in cells of model group increased significantly(P<0.05);the results of real-time PCR showed that the expression levels of NLRP3,ASC,caspase-1,IL-1β and IL-18 mRNA in cells of model group increased significantly(P<0.05);the results of Western blotting showed that the protein expression levels of NLRP3,ASC,caspase-1,IL-1β and IL-18 proteins in cells of model group increased significantly(P<0.05),and the immunofluorescence staining results showed that the expression levels of iNOS and NF-κB protein in cells of model group increased,and the expression levels of Nrf2 and HO-1 decreased,with statistically significant differences(P<0.05).Compared with model group,the release amount of NO in cells of SEN group and MCC950 group decreased,and the expression levels of NLRP3,ASC,caspase-1,IL-1β and IL-18 mRNA and proteins decreased,with statistically significant differences(P<0.05);in the SEN group,the expression levels of iNOS and NF-κB decreased,and immunofluorescence staining showed that Nrf2 was translocated into the nucleus,and the expression levels of Nrf2 and HO-1 proteins increased significantly,with statistically significant differences(P<0.05).Conclusions SEN could alleviate the inflammatory response of mouse microglia cells induced by LPS and inhibit the activation and expression of NLRP3 inflammasome,with an effect comparable to that of the inflammasome inhibitor MCC950.The mechanism may be related to the regulation of the expression of upstream factors Nrf2 and HO-1.
4.Comparison of clinical characteristics between primary bilateral macronodular adrenal hyperplasia and adrenal cortisol-producing adenoma
Bing LI ; Ming-Xiu YANG ; Huai-Jin XU ; Jing-Xuan WANG ; Qing-Zheng WU ; Ya-Jing WANG ; Yi-Jun LI ; Kang CHEN ; Yu CHENG ; Qi NI ; Ya-Qi YIN ; Li ZANG ; Qing-Hua GUO ; Jian-Ming BA ; Wei-Jun GU ; Jing-Tao DOU ; Zhao-Hui LYU ; Yi-Ming MU
Medical Journal of Chinese People's Liberation Army 2025;50(7):779-785
Objective To comparatively analyze the clinical characteristics of primary bilateral macronodular adrenal hyperplasia(PBMAH)and adrenal cortisol-producing Adenoma(CPA),and enhance the understanding of two diseases.Methods The clinical data of 85 PBMAH patients(PBMAH group)and 195 CPA patients(CPA group)diagnosed at Department of Endocrinology,the First Medical Center of Chinese PLA General Hospital,from September 2014 to August 2024 were retrospectively analyzed.The demographic characteristics,comorbidities,biochemical indicators,adrenocorticotropic hormone-cortisol(ACTH-F)levels,and adrenal imaging features and treatment conditions were compared between the two groups.Results(1)General characteristics:Compared with CPA group,PBMAH group had older age at diagnosis and a higher proportion of male patients.(2)Clinical characteristics:Compared with CPA group,PBMAH group had a longer disease duration,a higher proportion of subclinical Cushing's syndrome(CS),and a higher proportion of hypertension,impaired glucose tolerance/diabetes,bone mass reduction or osteoporosis,with higher serum potassium levels,and the differences were statistically significant(P<0.01).(3)Hormone levels:Both PBMAH and CPA groups showed ACTH-F rhythm disorder,significantly increased cortisol levels and suppressed ACTH.Compared with PBMAH group,CPA group had stronger autonomous cortisol secretion ability,manifested by increased midnight serum cortisol(F0:00),16:00 serum cortisol(F16:00),24-hour urinary free cortisol(24 h UFC)levels and lower 8:00 serum ACTH(ACTH8:00)and 16:00 serum ACTH(ACTH16:00)(P<0.01).After low-dose dexamethasone suppression test(LDDST),CPA group showed lower suppression rates of ACTH and cortisol,and higher proportions of paradoxical elevation in serum cortisol and 24 h UFC compared with PBMAH(P<0.01).Conclusions PBMAH has a longer disease course and higher proportions of comorbid metabolic disorders than CPA,mostly manifested as subclinical Cushing's syndrome.CPA has stronger autonomous cortisol secretion ability,with cortisol less likely to be suppressed after LDDST and more obvious paradoxical elevation of cortisol and 24 h UFC.
5.Characteristics analysis of multimodal metabolic disorders in subclinical Cushing's syndrome patients with different cortisol levels
Ya-Jing WANG ; Bing LI ; Huai-Jin XU ; Qi NI ; Ya-Qi YIN ; Yi-Jun LI ; Li ZANG ; Yu CHENG ; Kang CHEN ; Qing-Hua GUO ; Jian-Ming BA ; Wei-Jun GU ; Jing-Tao DOU ; Zhao-Hui LYU ; Yi-Ming MU
Medical Journal of Chinese People's Liberation Army 2025;50(7):793-799
Objective To characterize multimodal metabolic disorders in subclinical Cushing's syndrome(SCS)patients with different cortisol levels,providing a reference for clinical diagnosis and treatment.Methods A retrospective analysis was conducted on the clinical data of 165 SCS patients diagnosed at the First Medical Center of Chinese PLA General Hospital due to adrenal masses from January 2014 to October 2024.Using the serum cortisol levels after the midnight 1 mg dexamethasone suppression test(1 mg DST)as the cut-off point,SCS patients were divided into high-level group(1 mg DST-F>138 nmol/L,n=96)and low-level group(50 nmol/L<1 mg DST-F≤138 nmol/L,n=69).The differences in age,gender,body mass index(BMI),blood pressure,glucolipid metabolism indices,electrolytes,hormone levels,and imaging features of adrenal adenoma(such as CT values)were compared between the two groups.Multivariate linear regression was used to analyze the correlation between CT values and metabolic indices.Results Compared with low-level group,patients in high-level group were younger(54.0±11.3 vs.57.7±10.3,P=0.034),while there were no statistically significant differences in gender ratio or BMI between the two groups(P>0.05).Both groups exhibited decreased adrenocorticotropic hormone(ACTH)levels and disrupted circadian rhythm.Compared with low-level group,high-level group showed significantly higher F0:00 levels[250.00(170.07,422.53)nmol/L vs.110.00(82.74,133.90)nmol/L]and 24-hour urinary free cortisol(24 h UFC)[568.40(377.80,875.45)nmol/24 h vs.369.40(265.40,494.69)nmol/24 h](P<0.001),with no significant differences in serum F8:00,or 1 mg DST ACTH0:00 levels(P>0.05).Except for the fasting C-peptide level in the high-level group being higher than that in low-level group[(2.88±1.01)ng/ml vs.(2.46±0.78)ng/ml,P=0.024],there were no significant differences in blood pressure,blood lipids,glycated hemoglobin(HbA1c),fasting blood glucose,fasting insulin,serum electrolytes,uric acid,and other indices between the two groups(P>0.05).The CT value of adrenal adenoma during contrast-enhanced scanning was higher in high-level group[80.00(17.80,93.00)Hu vs.52.00(35.50,75.00)Hu,P=0.006]compared with low-level group.Multivariate linear regression analysis revealed that diastolic blood pressure was positively correlated with CT values of adrenal adenomas in both plain scanning(β=0.49,95%CI 0.09-0.90)and contrast-enhanced scanning(β=2.08,95%CI 0.76-3.39),while triglyceride levels were negatively correlated with plain scanning CT values(β=-5.77,95%CI-10.88--0.66).Conclusion Patients with SCS at different cortisol levels differ in age,fasting C-peptide levels,and CT values.CT values may serve as potential imaging markers to assess metabolic risk in SCS patients.
6.Clinical characteristics of clinical and subclinical Cushing's syndrome caused by primary bilateral macronodular adrenal hyperplasia
Huai-Jin XU ; Bing LI ; Kang CHEN ; Hui-Xin ZHOU ; Ya-Jing WANG ; Li ZANG ; Xian-Ling WANG ; Yu CHENG ; Jin DU ; Qing-Hua GUO ; Wei-Jun GU ; Zhao-Hui LYU ; Jian-Ming BA ; Jing-Tao DOU ; Yi-Ming MU
Medical Journal of Chinese People's Liberation Army 2025;50(7):800-807
Objective To investigate the clinical characteristics of patients with clinical and subclinical Cushing's syndrome caused by primary bilateral macronodular adrenal hyperplasia(PBMAH).Methods A retrospective analysis was performed on the clinical data of 198 patients with Cushing's syndrome caused by PBMAH diagnosed in the First Medical Center of Chinese PLA General Hospital from January 2004 to October 2024.According to clinical manifestations,the patients were classified into clinical type Cushing's syndrome(n=61)and subclinical type Cushing's syndrome(n=137),and the clinical characteristics of the two types were compared.Results The mean age at diagnosis of patients with PBMAH-induced Cushing's syndrome was(53.5±10.4)years,including 118 males and 80 females,with a male-to-female ratio of 1.475:1.Compared with the subclinical type,the clinical type had a higher proportion of females,higher levels of serum cortisol,24-hour urine free cortisol(24 h UFC),and inhibited serum cortisol after low-dose dexamethasone suppression.Additionally,the clinical type had lower plasma ACTH,larger adrenal nodules and a higher risk of surgery(P<0.05)compared with those in subclinical type.The incidences of hypertension,dyslipidemia,obesity,diabetes mellitus,hypokalemia,vitamin D deficiency,osteoporosis,coronary heart disease,and cerebrovascular disease in patients with Cushing's syndrome caused by PBMAH were 87.9%,50.5%,37.1%,36.9%,27.8%,25.9%,18.7%,18.7%and 12.1%,respectively.Among them,compared with subclinical type patients,clinical type patients had higher incidence of hypokalaemia,vitamin D deficiency and osteoporosis(P<0.05),while there were no statistically significant differences in the incidences of other comorbidities between the two types(P>0.05).The results of postoperative follow-up for PBMAH patients showed that the short-term biochemical remission rate of unilateral total adrenalectomy was 41.5%(22/53)and the long-term biochemical remission rate was 32.0%(8/25).The short-term biochemical remission rate of unilateral partial(or nodular)adrenalectomy was 52.9%(9/17),and the long-term biochemical remission rate was 14.3%(1/7).All patients who underwent unilateral total adrenalectomy plus contralateral partial resection developed adrenal insufficiency(3/3),and 1 patient(1/3)relapsed 3.4 years after surgery.Conclusion Clinical and subclinical types of Cushing's syndrome caused by PBMAH have their distinct clinical characteristics.Surgery is an effective treatment for PBMAH,but a certain proportion of patients fail to achieve biochemical remission after non-bilateral total adrenalectomy.
7.Correlation between dynamic contrast-enhanced MRI imaging and clinical pathological features of invasive breast cancer and lymphovascular invasion
Shi-Qi GUO ; Yu-Jiao XIE ; Qing-Yang LI ; Si-Yi CHEN ; Jia-Hong SUN ; Zhao-Feng GAO ; Jun-Qing LIANG ; Yu-Hui CHEN ; Bao-Shi BAO ; Li ZHU ; Jian-Dong WANG
Medical Journal of Chinese People's Liberation Army 2025;50(7):847-854
Objective To explore the relationship between dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)and clinical pathological features of invasive breast cancer and lymphovascular invasion(LVI).Methods Imaging and clinical pathological data were retrospectively collected from 508 patients with invasive breast cancer who underwent breast DCE-MRI at the First Medical Center of Chinese PLA General Hospital from January 2019 to August 2021.Patients were divided into the LVI-positive(LVI+)group(n=79)and LVI-negative(LVI-)group(n=429)based on postoperative pathological results.Univariate and multivariate logistic regression analyses were used to identify risk factors for LVI.Results Compared with LVI-group,LVI+group had a higher proportion of patients aged<45 years(44.3%vs.27.0%,P=0.002),non-mass-like enhancement(NME)(31.7%vs.17.7%,P=0.004),Ki-67 expression rate(40.0%vs.30.0%,P<0.001),high Ki-67 expression(94.9%vs.78.1%,P=0.001),Luminal B subtype(76.0%vs.60.1%,P=0.008),and positive axillary lymph nodes rate(72.2%vs.31.5%,P<0.001),while the proportion of Luminal A subtype was lower(2.5%vs.21.5%,P<0.001).Univariate and multivariate logistic regression analyses showed that age≥45 years(OR=0.468,95%CI 0.280-0.783,P=0.004)was an independent protective factor for LVI,while NME(OR=1.987,95%CI 1.126-3.444,P=0.016)was an independent risk factor.Compared with Luminal A subtype,patients with Luminal B subtype(OR=10.482,95%CI 3.164-64.923,P=0.001),HER-2 overexpression subtype(OR=11.571,95%CI 2.755-79.341,P=0.003)and triple-negative subtypes(OR=8.433,95%CI 1.985-57.908,P=0.009)had a higher risk of LVI.Conclusions Age≥45 years is an independent protective factor for LVI,while NME is an independent risk factor.Among molecular subtypes,patients with Luminal B,HER-2 overexpression and triple-negative subtypes have a higher risk of LVI compared with the Luminal A subtype.
8.Clinical characteristics of 10 cases of immune checkpoint inhibitor-related diabetes mellitus and literature review
Wen-Wen GONG ; Shu LI ; Yu-Long CHEN ; Li ZANG ; Jin DU ; Xian-Ling WANG ; Zhao-Hui LYU ; Qing-Hua GUO
Medical Journal of Chinese People's Liberation Army 2025;50(9):1103-1109
Objective To analyze the clinical characteristics,treatment,and prognosis of immune checkpoint inhibitor-related diabetes mellitus(ICI-DM).Methods The clinical characteristics,laboratory examinations,treatment regimens,and follow-up outcomes of 10 ICI-DM patients who were diagnosed and treated in the First Medical Center of Chinese PLA General Hospital between July 2019 and December 2024 were retrospectively analyzed.Relevant literatures were retrieved from domestic and foreign databases such as PubMed,CNKI,and VIP.The clinical characteristics of ICI-DM were summarized based on the literature results.Results All 10 patients were PD-1 inhibitor users,including 5 males and 5 females,with a median age of 54.5(51.3,64.0)years and a body mass index(BMI)of(22.0±2.15)kg/m2.Among them,9 cases(90.0%)were fulminant type 1 diabetes mellitus(FT1DM);9 cases(90.0%)had a severity of adverse events reaching grade 3-4 according to the Common Terminology Criteria for adverse events(CTCAE).The median time from PD-1 inhibitor treatment to the occurrence of the classic diabetes symptoms referred to as"three more and one less"(polyuria,polydipsia,polyphagia,and weight loss)in all patients was 145.5(110.5,204.8)days,and the medication duration was 6.0(4.3,7.8)cycles.The average blood glucose level of the 10 patients at the time of consultation was 25.3(10.0-41.4)mmol/L,and the glycated hemoglobin(HbA1c)level was 8.0%(6.6%-10.9%).Eight patients had fasting and 2-hour C-peptide levels<0.1 ng/ml(fasting C-peptide from<0.010 to 0.067 ng/ml,2-hour C-peptide from<0.010 to 0.077 ng/ml).Nine of the 10 patients were negative for diabetes autoantibodies,while 1 was not tested.All 10 patients were successfully treated with insulin and other therapies.During the follow-up after discharge,all patients still relied on insulin treatment,and no significant recovery of pancreatic islet β cell function was observed compared with that at discharge.Literature review revealed that ICI-DM was more common in PD-1 inhibitor users,with clinical mainly manifested as diabetic ketoacidosis(DKA)(65.4%)and diabetic ketosis(13.1%).Patients had severely impaired pancreatic islet function and required long-term insulin treatment,and some cases were complicated by thyroid or pituitary dysfunction.Conclusions ICI-DM typically presents as FT1DM,often manifesting with DKA or diabetic ketosis at onset.It is characterized by severe and irreversible loss of pancreatic islet function,necessitating lifelong insulin therapy.To enable early detection and prompt treatment,close monitoring of blood glucose is essential during ICI treatment.
9.COCKROACH SURVEILLANCE IN LANZHOU FROM 2016 TO 2023
Ying ZHANG ; Jing ZUO ; Qing-Ming SHI ; Zi-Peng LI ; Wen-Juan BA ; Zhi-Qing LI ; Ai-Miao LIAO ; Jing-Jing YU ; Guo-Jing BAO ; Xing LI ; Jun GAN ; Xiao-Lei YE
Acta Parasitologica et Medica Entomologica Sinica 2025;32(2):119-122
Objective To investigate the population composition,seasonal dynamics,and infestation levels of cockroaches in Lanzhou,China,and to provide information for the scientific development of cockroach control strategies.Methods Monitoring was conducted at three locations using the sticky trap method.Habitats included farm product markets,catering establishments,hotels,hospitals,and residential areas.Results From 2016 to 2023,the average cockroach density was 0.77 insects per board,with an average infestation rate of 10.84%.Blattella germanica was the dominant species.Seasonal density of cockroaches showed an approximately unimodal distribution,peaking in September.The highest average density and infestation rates were observed in farm product markets.Conclusions Cockroach density and infestation levels in Lanzhou remained relatively low.A comprehensive prevention and control strategy focusing on environmental management in key areas should be implemented according to the seasonal fluctuations.
10.Rapid Identification of Textile Fiber Composition Using Microtube Plasma Ionization Mass Spectrometry Combined with Random Forest Algorithm
Yu-Han SHANG ; Yue-Guang LYU ; Xian-Shuang MENG ; Qing LYU ; Xiang-Yu GUO ; Qing ZHANG
Chinese Journal of Analytical Chemistry 2025;53(8):1331-1341,中插93-中插95
A rapid and accurate method for textile fiber identification was developed for quality control and consumer protection.This method utilized electric soldering iron burning-mesh collision enhanced microtube plasma ionization mass spectrometry(ESIB-MC-μTP-MS)to acquire textile fiber MS data and used a random forest(RF)prediction model to identify fiber composition based on these MS data.The MC-μTP device involved in the method was a homemade low-temperature plasma ionization device constructed using cost-effective and readily available components.The system was applicable for direct analysis of small amount of textile samples without any complex sample pretreatment processes.Characteristic thermal decomposition products of different fibers were generated via soldering iron burning(350℃)in ambient atmosphere,and were subsequently analyzed by a mass spectrometer,with each analysis completed within 5 s.Raw MS data underwent noise reduction,normalization,and global binning steps to form a dataset,and its intrinsic class separability was evaluated using principal component analysis(PCA)combined with k-means clustering.Then,the RF model was trained based on the dimensionality-reduced textile fiber dataset.After grid search optimization,this model demonstrated robust performance with a 0.9762 out-of-bag score,a 0.9683 cross-validation accuracy(5-fold),and a 0.9636 test accuracy,supported by precision,recall,and F1-scores exceeding 0.889 for all fiber classes.The method was applied to analysis of 30 luxury apparel samples from eight brands,among which 20 samples achieved 100%prediction confidence,aligning with labeled compositions.The identification result of two low-confidence samples was further confirmed using attenuated total reflection Fourier transform infrared spectroscopy(ATR-FT-IR).The method has been proven to be simple,portable and with minimal sample requirements for on-site customs inspections,providing a viable tool in the fight against counterfeit products,therefore supporting regulatory enforcement and consumer trust in the textile goods market.

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