Objective: To establish a method for determining the molecular weight and molecular weight distribution of Poly(Lactide-co-Glycolide Acid) (PLGA) using Size Exclusion Chromatography-Refractive Index-Multiangle Laser Light Scattering (SEC-RI-MALLS) and Size Exclusion Chromatography-Refractive Index (SEC-RID), and to compare the results obtained from these two methods.
Methods: For SEC-RI-MALLS, tetrahydrofuran was used as the mobile phase, Shodex GPC KF-803L was employed as the chromatographic column with a flow rate of 1 mL·min^-1, column temperature at 30 ℃, and an injection volume of 100 μL. For SEC-RID, tetrahydrofuran was also used as the mobile phase, Agilent PLgel 5 μm MIXD-D was used as the chromatographic column with a flow rate of 1 mL·min^-1, column temperature at 30 ℃, differential detector temperature at 35 ℃, and an injection volume of 20 μL. The molecular weight and molecular weight distribution were calculated using Agilent’s GPC software. The newly established methods were validated methodologically, and the molecular weight and molecular weight distribution of 13 batches of samples were determined.
Results: The precision, accuracy, stability, and repeatability tests for SEC-RI-MALLS showed RSD values of 1.35%, 1.58%, 1.53%, and 1.26%, respectively. The SEC-RID method exhibited good linearity (r=0.999 9), with RSD values for precision, accuracy, stability, and repeatability tests (n=6) of 2.05%, 1.62%, 1.30%, and 2.97%, respectively. The results obtained from SEC-RI-MALLS were lower than those from SEC-RID, and the molecular weight distribution coefficient was smaller, but the results from the paired T-test performed with the value measured by SEC-RID method and the value measured by SEC-RI-MALLS method multiplied a conversion coefficient of 1.5 showed no significant difference between the two methods.
Conclusion: Both methods are stable and reliable, and can be used for the determination of PLGA molecular weight and molecular weight distribution based on the specific situations.

Objective: To evaluate the effects of a multidisciplinary weight management intervention, so as to provide a reference for the formulation of overweight and obesity intervention measures. Methods: From April to September 2025, overweight and obese residents aged 18-60 years who participated in a weight loss competition at the Health Management Center of Beilun People's Hospital in Ningbo City were selected as study subjects. They were divided into a control group and an intervention group. The control group received conventional weight management, while the intervention group received the multidisciplinary integrated weight management in addition to the conventional weight management, for a total intervention period of 8 weeks. Weight, body mass index (BMI), waist circumference, hip circumference, waist-to-hip ratio, fasting blood glucose (FBG), triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and blood pressure were collected before and after the intervention through physical examinations and laboratory tests. The generalized estimating equations (GEE) method was employed to analyze the differences in indicators between the two groups before and after the intervention. Results: The control group comprised 241 participants, including 161 females (66.80%), with a mean age of (35.66±7.80) years. The intervention group consisted of 127 participants, including 86 females (67.72%), with a mean age of (36.80±7.05) years. No statistically significant differences were observed between the two groups at baseline in terms of age, gender, weight, BMI, or waist-to-hip ratio (all P>0.05). Results from the GEE analysis indicated significant interactions between group and time for weight, BMI, waist circumference, and hip circumference (all P<0.05) with greater reductions in these parameters observed in the intervention group compared to the control group before and after the intervention. Similarly, significant interactions between group and time were observed for FBG, TG, TC, and LDL-C (all P<0.05), with the intervention group demonstrating larger decreases in these markers compared to the control group. However, no statistically significant interactions between group and time were observed for waist-to-hip ratio, HDL-C, systolic blood pressure, and diastolic blood pressure (all P>0.05). Following the intervention, a weight loss exceeding 10% was achieved by 13 participants (5.39%) in the control group and 62 participants (48.82%) in the intervention group. The proportion of individuals with a weight loss exceeding 10% was significantly higher in the intervention group compared to the control group (P<0.05). Conclusion Compared to conventional weight management, multidisciplinary integrated weight management demonstrated greater efficacy in improving weight-related indicators and blood glucose, blood lipids, and enhancing weight loss outcomes among overweight and obese residents.

Objective:To explore the value of dual-layer detector spectral CT quantitative parameters in evaluating the treatment response of neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanced rectal cancer (LARC).Methods:The study was a cross-sectional study. From May 2021 to March 2023, a total of 52 patients with LARC who received complete nCRT and were pathologically confirmed rectal adenocarcinoma at the Guangdong Province Hospital of Traditional Chinese Medicine were retrospectively enrolled. Each patient underwent spectral CT examination before and after nCRT, including plain scan, arterial phase (AP), and venous phase (VP) scans. According to the tumor regression grade, the patients were divided into the good response ( n=20) and the poor response group ( n=32). Measurements of the primary tumor′s spectral CT parameters, including effective atomic number (Z eff) at plain scan, iodine concentration (IC), CT values of 40 keV and 100 keV virtual monochromatic image (VMI) at dual-enhanced phases, were taken before and after nCRT. Additionally, the normalized iodine concentration (NIC), spectral curve slope (λHU), and the change rate of the above parameters before and after nCRT were calculated. The independent sample t-test or Mann-Whitney U test was used to compare the differences between the two groups. The receiver operating characteristic (ROC) curve was used to assess the efficacy of various metrics in evaluating the tumor treatment response of nCRT. A binary logistic regression analysis of combined parameter results was performed for the parameters with the areas under curve (AUC)>0.75, and the AUC of the combined parameter was evaluated. Results:There were significant differences in NIC AP and λHU VP before nCRT, NIC VP and λHU VP after nCRT, and the change rates of Z eff, NIC AP, NIC VP and λHU AP between the good response group and the poor response group ( P<0.05). The remaining parameters showed no statistically significant difference ( P>0.05). The ROC curve results showed that the AUCs of the above 8 parameters for evaluating tumor treatment response of nCRT were 0.702, 0.655, 0.695, 0.769, 0.738, 0.807, 0.791, and 0.677, respectively. The AUC of the combined model of the three parameters with AUC>0.75 (λHU VP after nCRT, the change rate of NIC AP and NIC VP) was 0.869, with 80.0% sensitivity and 84.4% specificity. Conclusion:The quantitative parameters derived from spectral CT may provide new markers for evaluating the response to nCRT treatment in patients with LARC. The multi-parameter combined model can improve diagnostic efficacy.

Objective:To analyze the clinical characteristics of children with systemic lupus erythematosus (SLE) combined with thrombotic microangiopathy (TMA), and clarify the clinical outcomes and related risk factors of pediatric patients through their treatment and follow-up.Methods:This was a single-center retrospective case-control study. Children diagnosed with SLE combined with TMA between January 2017 and January 2023 at Beijing Children′s Hospital, Capital Medical University, were selected as the TMA group, and SLE children without TMA were selected as the control group.According to the prognosis, children in the TMA group were further divided into the good prognosis group and the poor prognosis group.The data of the children were collected, including age, gender, SLE disease activity, clinical presentations at the time of diagnosis and at the time of thrombosis, laboratory examinations, treatment strategies, prognosis, and follow-up results.The chi-square test and Z-test were used for comparison of count data.The t-test was used for comparison of metrological pairing data.The Fisher′s exact test was used to compare the differences between the 2 groups in categorical variables.The univariate Logistic regression was used to analyze the risk factors of poor prognosis. Results:There were 29 cases in the TMA group, and the incidence of TMA accounted for 2.53% of SLE patients; 33 cases were in the control group.The age at diagnosis of TMA was 13 years and 5 months (ranging from 9 years, 1 month and 5 days to 17 years and 4 months).The common clinical manifestations in order of prevalence were renal involvement (28 cases, 96.55%), hematologic involvement (26 cases, 89.66%), serous effusion (17 cases, 58.62%), rash (13 cases, 44.82%), and neurologic involvement (12 cases, 41.38%).Pleurisy or pericarditis, renal involvement and neurological involvement occurred more often in the TMA group than in the control group (17 cases vs.3 cases, 28 cases vs.10 cases, 12 cases vs.3 cases), and the TMA group showed less facial rash and arthritis than the control group (13 cases vs.25 cases, 4 cases vs.17 cases), and the differences were statistically significant (all P<0.05).The Systemic Lupus Erythematosus Disease Activity Index score in the TMA group [(24.14±9.42) scores] was significantly higher than that in the control group [(10.18±9.42) scores], and the difference was statistically significant ( t=3.233, P<0.05).The hemoglobin level, platelet count, and complement C3 level of the children in the TMA group were significantly lower than those in the control group, whereas the double stranded DNA antibody, lactate dehydrogenase, D-dimer, urea, creatinine, ferritin level, and urine protein quantitation were significantly higher than those in the control group, and the differences were statistically significant (all P<0.05).In the TMA group, 5 cases had decreased ADAMTS13 activity, and 5 cases had significantly increased complement C5b9.A total of 15 cases (51.72%) in the TMA group underwent renal biopsy, and 13 of them had combined renal TMA.In the TMA group, 28 patients (96.6%) received hormone therapy, 17 patients received plasma exchange, and 12 patients were treated with immunosuppressants and biologics; 19 patients (65.5%) improved, and 10 patients (34.5%) gave up the treatment due to deterioration of the disease.The urea level and peripheral blood fragmented erythrocyte rate in the good prognosis group were significantly lower than those in the poor prognosis group [(13.18±4.39) mmol/L vs.(21.16±10.14) mmol/L, t=2.975, P=0.006; 8/17 (47.06%) vs.7/7 (100%), χ2=5.929, P=0.015].The univariate Logistic regression analysis showed that the fragmented erythrocyte, ADAMTS13 activity and urea were the independent risk factors for poor prognosis (all P<0.05). Conclusions:SLE patients with moderate-to-severe disease activity, especially children with hemolytic anemia, thrombocytopenia, and renal dysfunction as prominent manifestations, should be alert to the risk of TMA.Early diagnosis and treatment are crucial.

Objective To explore the predicting value of quantitative CT features of peritumoral nodules for the risk of thymic epi-thelial tumors(TETs).Methods A total of 108 patients with TETs confirmed by pathology were analyzed retrospectively.Accord-ing to the WHO classification of thymic tumors,the patients were divided into high-risk group and low-risk group.The quantitative CT features included the long diameter,volume,mass,and distance between peritumoral nodules and main tumor.The values of these features were assessed using the Mann-Whitney U test,and the thresholds were determined using the receiver operating characteristic(ROC)curve.Results Among 108 TETs patients,there were 45 patients with peritumoral nodules on chest CT,including 30 high-risk group and 15 low-risk group,respectively.Interobserver consistencies were well with intraclass correlation coefficient(ICC)between 0.886 and 0.907.The long diameter,volume,and mass of peritumoral nodules were greater in the high-risk group than in the low-risk group(P＜0.05),and there was no significant difference in the distance to the main tumor(P＞0.05).The mass of peritumoral nodules had the best diagnostic performance in predicting TETs risk,and the thresholds was 27.84 mg with the area under the curve(AUC)of 0.889,sensitivity of 83.3％,specificity of 87.5％,and accuracy of 85.3％,respectively.Conclusion The quantitative CT features of peritumoral nodules especially mass can be useful in predicting the risk of TETs.

Objective To explore the clinical value of models based on clinical features and enhanced MRI radiomics for predicting the occurrence of post-acute pancreatitis diabetes mellitus(PPDM-A).Methods A retrospective selection of 161 acute pancreatitis(AP)patients was conducted,comprising 99 in the non-PPDM-A group and 62 in the PPDM-A group.They were randomly divided into training set and test set in a ratio of 7∶3.Region of interest(ROI)were delineated and radiomics features were extracted on the late arterial phase MRI images.Optimal radiomics features were selected by maximum relevance and minimum redundancy(mRMR)and least absolute shrinkage and selection operator(LASSO).Support vector machine(SVM)was used to develop three predictive models.The efficacy of the models in predicting PPDM-A was evaluated,the receiver operating characteristic(ROC)curve was drawn,and the DeLong test was employed to assess the difference in predictive capability among the models.Results In the training set,the area under the curve(AUC)of the clinical model,radiomics model,and combined model were 0.702,0.810 and 0.901,respectively,and in the test set were 0.678,0.797 and 0.830,respectively.The DeLong test revealed a statistically significant difference in the predictive capability of the combined model compared to the clinical model both in the training and test sets(training set:P＜0.001;test set:P=0.019).Conclusion The combined model based on clinical features and enhanced MRI radiomics features demonstrates good predictive effi-cacy and can provide valuable insights for clinical interventions aimed at preventing PPDM-A.

Objective:To explore the application effect of breakthrough series (BTS) quality improvement model in the prevention of catheter-related bloodstream infection in hospitalized patients with indwelling non-cuffed catheter (NCC).Methods:Using a non synchronous pre and post control study method, convenience sampling was used to select NCC patients from four hospitals in Tianjin from January to September 2022 who received conventional nursing plans as the control group, and NCC patients from February to October 2023 who received nursing plans based on the BTS quality improvement model as the observation group. Compared the incidence of NCC related bloodstream infections between two groups of patients, the implementation of key preventive measures for NCC related bloodstream infections by nursing staff, and patient satisfaction.Results:Among the 984 patients included in the control group, there were 687 males and 297 females, aged (62.43 ± 13.77) years old; among the 959 patients included in the observation group, there were 651 males and 308 females, aged (61.96 ± 13.89) years old. After applying the improved model, the incidence of NCC related bloodstream infections in the observation group was 0.12‰ (1/8 676), lower than the control group′s 0.71‰ (7/9 827), and the difference was statistically significant ( χ 2=4.37, P<0.05) ;the implementation rate of key measures for preventing NCC related bloodstream infections in the observation group was 90.00% (54/60) for catheter outlet care and 91.67% (55/60) for maximizing sterile barrier, both higher than 70.37% (38/54) and 75.93% (41/54) in the control group, with statistical significance ( χ2=7.03, 5.30, both P<0.05); the total satisfaction rate of patients in the observation group was 92.91% (891/959), which was higher than 58.64% (577/984) in the control group, and the difference was statistically significant ( χ2=15.28, P<0.05). Conclusions:The implementation of BTS quality improvement model is helpful to improve the nursing quality of patients with indwelling NCC dialysis and improve the patient outcomes.

To investigate the levels and clinical significance of serum microRNA ( miR) -146a, miR-145, T-helpertype17 (Th17)/regulatory T cell (Treg) in children with respiratory syncytial virus (RSV) infectious pneumonia. The clinical data of 200 children with RSV infectious pneumonia admitted to Nantong Maternal and Child Health Hospital from June 2020 to June 2023 were retrospectively collected as the study group. At the same time, 200 children with mycoplasma pneumonia were selected as the common pneumonia group and 200 healthy children were selected as the healthy group. The levels of serum inflammatory factors [interleukin-6 (IL-6), interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α)] were detected by enzyme-linked immunosorbent assay. The expression levels of serum miR-146a and miR-145 were detected by RT-qPCR. The levels of Th17/Treg were detected by flow cytometry. The levels of miR-146a, miR-145, Th17/Treg and serum inflammatory factors were compared among the three groups. Pearson method was used to analyze the correlation between miR-146a, miR-145, Th17/Treg and serum inflammatory factors in children with RSV infectious pneumonia. The receiver operating characteristic (ROC) curve was drawn to analyze the diagnostic value of miR-146a, miR-145, Th17/Treg in children with respiratory syncytial virus infection pneumonia. The results showed that in the study group, miR-146a (2.01±0.58), miR-145 (1.81±0.46), Th17/Treg (1.09±0.31), IL-6 (7.82±2.11) ng/L and TNF-α (9.82±2.96) ng/L were higher than those in the common pneumonia group miR-146a (1.49±0.42), miR-145 (1.43±0.31), Th17/Treg (0.77±0.24), IL-6 (5.89±1.32) ng/L, TNF-α (7.34±2.32) ng/L and healthy group miR-146a (1.25±0.19), miR-145 (1.19±0.16), Th17/Treg (0.38±0.09), IL-6 (4.52±1.04) ng/L, TNF-α (5.39±1.07)ng/L. The levels of the above indexes in the common pneumonia group were higher than those in the healthy group, and the differences were statistically significant ( F=183.543, 175.938, 617.182, 226.657, 193.459, P<0.05). In the study group, IFN-γ (14.18±3.25) pg/ml was lower than that in the control group (19.52±5.13) pg/ml, but higher than that in the healthy group (9.77±2.40) pg/ml, and the difference was statistically significant ( F=335.432, P<0.05). Pearson correlation analysis showed that miR-146a, miR-145 and Th17/Treg were positively correlated with IL-6 and TNF-α ( P<0.05), but negatively correlated with IFN-γ ( P<0.05). ROC curve results showed that the area under the curve (AUC) of miR-146a, miR-145 and Th17/Treg in the diagnosis of RSV infectious pneumonia was 0.767, 0.762 and 0.790, respectively, while the combined detection of the three was 0.904. In conclusion, the levels of miR-146a, miR-145 and Th17/Treg are highly expressed in children with RSV infectious pneumonia, and are closely related to the inflammatory response of children. The combined detection of the three may have certain application value in the auxiliary diagnosis of RSV infectious pneumonia.

Objective:In clinical ultrasound examinations,it is challenging to perform quality control on the images of each fetal nuchal translucency(NT)and crown-rump length(CRL).However,small measurement differences can increase the probability of false-positive or false-negative diagnosis.Therefore,it is necessary to establish a quality control system for fetal NT examination.This study aims to control the quality of fetal NT and CRL measurements,evaluate the accuracy of ultrasound physicians in early pregnancy NT measurements,and analyze the impact of increased fetal structure screening on the detection rate of chromosomal abnormalities. Methods:Data were collected from cases before and after 12 months of NT examination quality control,with 2 214 before quality control and 2 538 cases after quality control.Three quality control data metrics were analyzed:NT multiple of median(NT-MoM),standard deviation(SD)of log10MoM[(SD)log10MoM],and the slope of NT on CRL(SNC).The performance of NT measurements was monitored through the individual CRL NT-MoM within the 0.9-1.1 MoM range of the normal median curve,while grouped based on different years of experience(＜3 years,3-6 years,＞6 years),and NT-MoM values among these groups were compared.Data on NT thickening,structural anomalies,and chromosomal abnormalities were retrospectively analyzed during the quality control period. Results:According to the curve equation of the American NTQR project group,the NT-MoM value before quality control was 0.921 7 MoM,the(SD)log10MoM value was 0.091 92,and the SNC value was 12.20％.After quality control,the NT-MoM value was 0.948 3 MoM,the(SD)log10MoM value was 0.094 81,and the SNC value was 11.43％.The comparison of NT-MoM values before and after quality control showed a statistically significant difference(P＜0.000 1).The comparison of NT-MoM values measured by ultrasound physicians with different years of experience before and after quality control also showed statistically significant differences(P＜0.000 1).The NT-MoM values for the 3-6 years and＞6 years groups were higher after quality control(P＜0.05),while the＜3 years group showed no significant difference before and after quality control(P＞0.05).After quality control,cases of NT thickening without significant structural abnormalities accounted for 19.05％,NT thickening with structural abnormalities accounted for 47.62％,and NT normal with structural abnormalities accounted for 33.33％.There were 36 cases of fetal heart abnormalities,accounting for 20.34％of the total abnormality rate,with a positive rate of 36％in chromosome tests. Conclusion:After quality control,ultrasound physicians measure NT more accurately,but differences among measurements remain.Measurements by experienced ultrasound physicians are closer to expected values,usually lower than expected.Monitoring fetal NT and CRL measurements helps improve measurement accuracy.Increasing structural screening during NT examinations,especially for the fetal heart,enhances the detection rate of chromosomal abnormalities.

To investigate the levels and clinical significance of serum microRNA ( miR) -146a, miR-145, T-helpertype17 (Th17)/regulatory T cell (Treg) in children with respiratory syncytial virus (RSV) infectious pneumonia. The clinical data of 200 children with RSV infectious pneumonia admitted to Nantong Maternal and Child Health Hospital from June 2020 to June 2023 were retrospectively collected as the study group. At the same time, 200 children with mycoplasma pneumonia were selected as the common pneumonia group and 200 healthy children were selected as the healthy group. The levels of serum inflammatory factors [interleukin-6 (IL-6), interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α)] were detected by enzyme-linked immunosorbent assay. The expression levels of serum miR-146a and miR-145 were detected by RT-qPCR. The levels of Th17/Treg were detected by flow cytometry. The levels of miR-146a, miR-145, Th17/Treg and serum inflammatory factors were compared among the three groups. Pearson method was used to analyze the correlation between miR-146a, miR-145, Th17/Treg and serum inflammatory factors in children with RSV infectious pneumonia. The receiver operating characteristic (ROC) curve was drawn to analyze the diagnostic value of miR-146a, miR-145, Th17/Treg in children with respiratory syncytial virus infection pneumonia. The results showed that in the study group, miR-146a (2.01±0.58), miR-145 (1.81±0.46), Th17/Treg (1.09±0.31), IL-6 (7.82±2.11) ng/L and TNF-α (9.82±2.96) ng/L were higher than those in the common pneumonia group miR-146a (1.49±0.42), miR-145 (1.43±0.31), Th17/Treg (0.77±0.24), IL-6 (5.89±1.32) ng/L, TNF-α (7.34±2.32) ng/L and healthy group miR-146a (1.25±0.19), miR-145 (1.19±0.16), Th17/Treg (0.38±0.09), IL-6 (4.52±1.04) ng/L, TNF-α (5.39±1.07)ng/L. The levels of the above indexes in the common pneumonia group were higher than those in the healthy group, and the differences were statistically significant ( F=183.543, 175.938, 617.182, 226.657, 193.459, P<0.05). In the study group, IFN-γ (14.18±3.25) pg/ml was lower than that in the control group (19.52±5.13) pg/ml, but higher than that in the healthy group (9.77±2.40) pg/ml, and the difference was statistically significant ( F=335.432, P<0.05). Pearson correlation analysis showed that miR-146a, miR-145 and Th17/Treg were positively correlated with IL-6 and TNF-α ( P<0.05), but negatively correlated with IFN-γ ( P<0.05). ROC curve results showed that the area under the curve (AUC) of miR-146a, miR-145 and Th17/Treg in the diagnosis of RSV infectious pneumonia was 0.767, 0.762 and 0.790, respectively, while the combined detection of the three was 0.904. In conclusion, the levels of miR-146a, miR-145 and Th17/Treg are highly expressed in children with RSV infectious pneumonia, and are closely related to the inflammatory response of children. The combined detection of the three may have certain application value in the auxiliary diagnosis of RSV infectious pneumonia.