Background The benchmark dose (BMD) method calculates the dose associated with a specific change in response based on a specific dose-response relationship. Compared with the traditional no observed adverse effect level (NOAEL) method, the BMD method has many advantages, and the 95% lower confidence limit of benchmark dose lower limit (BMDL) is recommended to replace NOAEL in deriving biological exposure limits. No authority has yet published any health-based guideline for rare earth elements. Objective To evaluate genotoxicity threshold induced by acute exposure to neodymium nitrate in mice using BMD modeling through micronucleus test and comet assay. Methods SPF grade mice (n=90) were randomly divided into nine groups, including seven neodymium nitrate exposure groups, one control group (distilled water), and one positive control group (200 mg·kg⁻¹ ethyl methanesulfonate), 10 mice in each group, half male and half female. The seven dose groups were fed by gavage with different concentrations of neodymium nitrate solution (male: 14, 27, 39, 55, 77, 109, and 219 mg·kg⁻¹; female: 24, 49, 69, 97, 138, 195, and 389 mg·kg⁻¹) twice at an interval of 21 h. Three hours after the last exposure, the animals were neutralized by cervical dislocation. The bone marrow of mice femur was taken to calculate the micronucleus rate of bone marrow cells, and the liver and stomach were taken for comet test. Results The best fitting models for the increase of polychromatophil micronucleus rate in bone marrow of female and male mice induced by neodymium nitrate were the exponential 4 model and the hill model, respectively. The BMD and the BMDL of female mice were calculated to be 31.37 mg·kg⁻¹ and 21.90 mg·kg⁻¹, and those of male mice were calculated to be 58.62 mg·kg⁻¹ and 54.31 mg·kg⁻¹, respectively. The best fitting models for DNA damage induced by neodymium nitrate in female and male mouse hepatocytes were the exponential 5 model and the exponential 4 model, respectively, and the calculated BMD and BMDL were 27.15 mg·kg⁻¹ and 11.99 mg·kg⁻¹ for female mice, and 16.28 mg·kg⁻¹ and 10.47 mg·kg⁻¹ for male mice, respectively. The hill model was the best fitting model for DNA damage of gastric adenocytes in both female and male mice, and the calculated BMD and BMDL were 36.73 mg·kg⁻¹ and 19.92 mg·kg⁻¹ for female mice, and 24.74 mg·kg⁻¹ and 14.08 mg·kg⁻¹ for male mice, respectively. Conclusion Taken the micronucleus rate of bone marrow cells, DNA damage of liver cells and gastric gland cells as the end points of genotoxicity, the BMDL of neodymium nitrate is 10.47 mg·kg⁻¹, which can be used as the threshold of genotoxic effects induced by acute exposure to neodymium nitrate in mice.

Objective:To identify tooth number abnormalities on pediatric panoramic radiographs based on deep learning.Methods:Eight hundred panoramic radiographs of children aged 4 to 11 years meeting the inclusion and exclusion criteria were selected and randomly assigned by writing programs in Python (version 3.9) to the training set (480 images), verification set (160 images) and internal test set (160 images), taken in Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology between November 2012 to August 2020. And all panoramic radiographs of children aged 4 to 11 years taken in the First Outpatient Department of Peking University School and Hospital of Stomatology from June 2022 to December 2022 were collected as the external test set (907 images). All of the 1 707 images were obtained by operators to determine the outline and to label the tooth position of each deciduous tooth, permanent tooth, permanent tooth germ and additional tooth. The deep learning model with ResNet-50 as the backbone network was trained on the training set, validated on the verification set, tested on the internal test set and external test set. The images of test sets were divided into two categories according to whether there was abnormality of tooth number, to calculate sensitivity, specificity, positive predictive value and negative predictive value, and then divided into four types of extra teeth and missing permanent teeth both existed, extra teeth existed only, missing permanent teeth existed only, and normal teeth number, to calculate Kappa values. Results:The sensitivity, specificity, positive predictive value and negative predictive value were 98.0%, 98.3%, 99.0% and 96.7% in the internal test set, and 97.1%, 98.4%, 91.9% and 99.5% in the external test set respectively, according to whether there was abnormality of tooth number. While images were divided into four types, the Kappa value obtained in the internal test set was 0.886, and that in the external test set was 0.912. Conclusions:In this study, a deep learning-based model for identifying abnormal tooth number of children was developed, which could identify the position of additional teeth and output the position of missing permanent teeth on the basis of identifying normal deciduous and permanent teeth and permanent tooth germs on panoramic radiographs, so as to assist in diagnosing tooth number abnormalities.

Objective To explore the association of suprapatellar pouch effusion with knee pain and serum levels of interleukin (IL)-6,IL-17,IL-23 in patients with knee osteoarthritis measured by magnetic resonance imaging (MRI).Methods 204 patients with knee osteoarthritis were enrolled into the study.Suprapatellar pouch effusion was measured by OSIRIS in both grade (0-3) and maximum area (cm2).Serum IL-6,IL-17,IL-23 were measured.Knee pain was assessed by Western Ontario and McMasters osteoarthritis index (WOMAC) questionnaire and Lequesne index.Characteristics of patients were recorded and body mass index (BMI) was calculated.Student t test or Chi-square test was used to compare means or proportions.Multivariable linear regression or logistic regression was used to determine risk factors (α=0.05).Results ① In the 204 patients [mean age (55±8) years,86.3％ were females],the prevalence of physiologic effusion (≤ 1) was 47.9％ while moderate or larger (≥2) effusion was 52.1％.② The age,labour intensity,serum levels of uric acid (sUA) and Lequesne index of higher grade effusion group were higher (P＜0.05) compared with lower grade effusion group.③ Suprapatellar pouch effusion maximum area was positively correlated with age (r=0.208,P=0.006),BMI (r=0.171,P=0.027) and labour intensity (r=0.189,P=0.013).④ Adjusted for age,gender and BMI,the results of Logistic regression analysis showed that:suprapatellar pouch effusion grades were positively correlated with Lequesne index [OR=1.120,95％CI(1.011,1.241),P=0.029] and negatively correlated with IL-23 [OR=0.768,95％CI (0.598,0.986),P=0.038].Suprapatellar pouch effusion was not independently associated with WOMAC index,IL-6 and IL-17.Conclusion The prevalence of suprapatellar pouch pathological effusion is 52.1％ in knee osteoarthritis.Suprapatellar pouch effusions is positively correlated with knee pain (Lequesne index) and negatively conrelated with IL-23.

OBJECTIVE:To establish the method for the determination of mildronate in human plasma and urine,and to study the pharmacokinetic characteristics in healthy volunteers. METHODS:After precipitating plasma and urine sample,LC-MS/MS method was adopted. Dikma Diamonsil C18 column was used with mobile phase consisted of methanol-water(containing 0.2% for-mic acid,0.3% ammonium acetate)(31∶69,V/V)at the flow rate of 0.6 ml/min. ESI was adopted in MRM mode,by using nega-tive ion. The ion for quantitative analysis were m/z 147.10→58.20 (mildronate) and m/z 152.00→110.10 (internal standard,acet-aminophen). The pharmacokinetic parameters of mildronate with single administration and multiple administration were calculated by using DAS 2.1 software and compared. RESULTS:The linear range of mildronate in plasma were 0.02-20 ng/ml(r=0.999 3) and in urine were 0.05-40 ng/ml(r=0.998 2). The lowest limits of quantitation were 0.02 and 0.05 ng/ml. Precision and recovery met the requirements of biological specimen determination,and endogenous impurities hadn’t effect on the determination. The main pharmacokinetics parameters of low-dose,medium-dose and low-dose(250,500,750 mg)of mildronate in plasma with single ad-ministration were as follows:t1/2 were(3.39±0.81),(5.52±0.57)and(5.32±0.96)h;tmax were(0.80±0.45),(1.38±0.43)and (1.10±0.36)h;cmax were(4.17±1.46),(8.08±1.04)and(15.04±1.86)ng/ml;AUC0-36 h were(24.55±5.81),(45.50±7.07)and (85.60 ± 13.09)ng·h/ml. In the dose range,cmax,AUC0-36 h h had a linear relationship with dose (R2 were 0.974 5 and 0.968 3). The main pharmacokinetic parameters of low-dose of mildronate with multiple administration after keeping stable were as follows:cmin was(0.28 ± 0.10)ng/ml;AUCs was(38.78 ± 4.18)ng·h/ml;cs was(1.62 ± 0.17)ng/ml;DF was(3.81 ± 1.14);t1/2 was(6.17 ± 1.46)h;tmax was(1.20 ± 0.33)h;cmax was(6.46 ± 1.96)ng/ml;AUC0-36 h was(40.33 ± 4.65)ng·h/ml;accumulation factor of cmax and AUC were(1.73±0.90)and(1.64±0.40). Compared with single administration,t1/2,cmax and AUC of mildronate with multiple admin-istration after keeping stable all changed,and tmax had no signifi-cant difference. After single administration,26 h accumulative excretion rate of those groups were (0.004 009 ± 0.001 1)%, (0.004 026±0.001 01)% and(0.003 858±0.000 68)% respec-tively. CONCLUSIONS:Established method is sensitive,accurate and specific,and suitable for the determination of mildronate concentration in human plasma and urine and pharmacokinetics study. Mildronate capsule shows certain accumulation effect in healthy volunteers,and linear pharmacokinetic characteristics.

Objective To analyze the reasons causing false positive results of white blood cells (WBC) detected by AVE‐763B automatic urine analyzer .Methods WBC positive samples ,detected by AVE‐763B automatic urine analyzer ,were re‐inspected by microscope .Results In the 740 positive samples ,224 cases were false positive ,the false‐positive rate was 30 .2% ,among which 145 cases could be correctly classified by using image analysis ,and the false‐positive rate reduced to 10 .7% .Conclusion Many fac‐tors could cause false positive results .To improve the accuracy of AVE‐763B urine analyzer ,re‐inspect should be performed .

OBJECTIVETo study the expression of Toll-like receptors (TLRs) mRNA in human trophoblast HTR-8/SVneo cells and the changes in indoleamine 2,3-dioxygenase (IDO) mRNA expression in response to TLR ligand stimulation.

METHODSThe expressions of TLRs and IDO mRNA in human HTR-8/SVneo cells were tested by RT-PCR, and the changes in IDO mRNA levels after exposure to TLR3, TLR4, TLR7/8, and TLR9 ligands were quantitatively analyzed with real-time PCR.

RESULTSIDO and TLR1-10 mRNAs were expressed in HTR-8/SVneo cells. As the cell culture time extended, IDO mRNA expression level tended to increase within 48 h. After stimulation with the TLR ligands, the expression of TLR-3 mRNA was down-regulated while the expression of TLR-4, 7, 8, and 9 mRNA up-regulated. Stimulation of the cells with poly(I:C) lowered the expression of IDO mRNA while IFN-γ increased its expression.

CONCLUSIONSThe expression of IDO mRNA is associated with the nutrition of the maternal-fetal interface. Stimulation with the TLR ligands affects the expression of IDO and TLR mRNA expressions in the cells, which verifies the functional activity of TLRs and suggests a role of IDO in TLR pathway-dependent antiviral immunity.

Cell Line ; Female ; Humans ; Indoleamine-Pyrrole 2,3,-Dioxygenase ; genetics ; metabolism ; Interferon-gamma ; pharmacology ; Ligands ; Poly I-C ; pharmacology ; RNA, Messenger ; metabolism ; Toll-Like Receptors ; genetics ; metabolism ; Trophoblasts ; cytology ; metabolism

Objective To study the expression of Toll-like receptors (TLRs) mRNA in human trophoblast HTR-8/SVneo cells and the changes in indoleamine 2,3-dioxygenase (IDO) mRNA expression in response to TLR ligand stimulation. Methods The expressions of TLRs and IDO mRNA in human HTR-8/SVneo cells were tested by RT-PCR, and the changes in IDO mRNA levels after exposure to TLR3, TLR4, TLR7/8, and TLR9 ligands were quantitatively analyzed with real-time PCR. Results IDO and TLR1-10 mRNAs were expressed in HTR-8/SVneo cells. As the cell culture time extended, IDO mRNA expression level tended to increase within 48 h. After stimulation with the TLR ligands, the expression of TLR-3 mRNA was down-regulated while the expression of TLR-4, 7, 8, and 9 mRNA up-regulated. Stimulation of the cells with poly(I:C) lowered the expression of IDO mRNA while IFN-γincreased its expression. Conclusions The expression of IDO mRNA is associated with the nutrition of the maternal-fetal interface. Stimulation with the TLR ligands affects the expression of IDO and TLR mRNA expressions in the cells, which verifies the functional activity of TLRs and suggests a role of IDO in TLR pathway-dependent antiviral immunity.

Objective To study the expression of Toll-like receptors (TLRs) mRNA in human trophoblast HTR-8/SVneo cells and the changes in indoleamine 2,3-dioxygenase (IDO) mRNA expression in response to TLR ligand stimulation. Methods The expressions of TLRs and IDO mRNA in human HTR-8/SVneo cells were tested by RT-PCR, and the changes in IDO mRNA levels after exposure to TLR3, TLR4, TLR7/8, and TLR9 ligands were quantitatively analyzed with real-time PCR. Results IDO and TLR1-10 mRNAs were expressed in HTR-8/SVneo cells. As the cell culture time extended, IDO mRNA expression level tended to increase within 48 h. After stimulation with the TLR ligands, the expression of TLR-3 mRNA was down-regulated while the expression of TLR-4, 7, 8, and 9 mRNA up-regulated. Stimulation of the cells with poly(I:C) lowered the expression of IDO mRNA while IFN-γincreased its expression. Conclusions The expression of IDO mRNA is associated with the nutrition of the maternal-fetal interface. Stimulation with the TLR ligands affects the expression of IDO and TLR mRNA expressions in the cells, which verifies the functional activity of TLRs and suggests a role of IDO in TLR pathway-dependent antiviral immunity.

Objective To evaluate the short-term efficacy and safety of sevelamer hydrochloride in treating maintenance hemodialysis (MHD) patients with hyperphosphemia.Methods A multicenter,open-labeled,self-control study was performed.Phosphate binders were discontinued during a two-week washout period.Patients with more than 1.78 mmol/L serum phosphorus after two-week washout period were eligible for the trial.The dose was adjusted every two weeks as necessary to achieve serum phosphorus control. Sevelamer hydrochloride was administered to 138 MHD patients for 10 weeks and a second two-week washout period followed.Results A total of 111 from 138 patients fulfilled the whole 14-week study. Mean serum phosphorus and calcium-phosphate products starte to decline after two-week sevelamer hydrochloride treatment. By the end of 10-week sevelamer hydrochloride treatment, mean serum level of phosphorus [(1.85±0.50) vs (2.57±0.54) mmol/L,P＜0.01],calcium-phosphate product [(4.16± 1.72) vs (5.79 ± 1.50) mmol2/L2,P＜0.01 ] and low density lipoprotein [(1.64±0.76) vs (2.31 ±0.87) mmol/L,P＜0.01] were significantly decreased,while the adjusted serum level of calcium and serum intact parathyroid hormone kept steady.Both serum phosphorus and calcium-phosphrus product increased after the second washout period, but the levels were still lower as compared to pre-treatment [(2.26±0.71) vs (2.57±0.54) mmol/L; (5.12±1.63) vs (5.79±1.50) mmol2/L2,P＜0.01].Of the 138 patients involved,214 episodes in 106 patients and 121 episodes in 89 patients were reported as adverse events and adverse drug reaction respectively. Gastrointestinal symptoms,of which most were mild or moderate,happened to 68.1％ (94/138) patients. Conclusions Sevelamer hydrochloride can control serum phosphorus and reduce the levels of calcium-phosphorus product and cholesterol.Slight gastrointestinal symptoms like constipation are common during the treatment.

Developing countries are facing a big challenge of how to promote sexual and reproductive healthe Poverty erasion.reproductive health service promotion,schools and communities intervention,discussion between children and their parents encouragment are helpful to solve the sexual and reproductive problems with the adolescents