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 explore the therapeutic effect and mechanism of umbilical cord mesenchymal stem cells (UC-MSC) in rats with primary graft dysfunction after lung transplantation. Methods Twenty-four male Lewis rats were randomly divided into donor and recipient groups, with 12 rats in each group. The recipients were further divided into 3 groups: blank control group, negative control group, and treatment group, with 4 rats in each group. The color, size and texture of the transplanted lungs were observed 72 h after lung transplantation. The ventilation status and progression of consolidation in the transplant lungs of rats in each group were evaluated by micro-CT. Plasma, transplant lung tissue and alveolar lavage fluid samples of recipient rats were collected. The wet/dry ratio of lung tissue was measured to evaluate the degree of pulmonary edema. Hematoxylin-eosin (HE) staining was used to evaluate the degree of lung tissue damage. Terminal deoxyribonucleic acid transferase mediated dUTP nick end labeling (TUNEL) staining was used to evaluate cell apoptosis. Myeloperoxidase (MPO) activity in lung tissue was detected, and enzyme-linked immunosorbent assay (ELISA) was used to detect interleukin (IL)-6, IL-10 and tumor necrosis factor (TNF)-α levels in plasma and alveolar lavage fluid. Results The appearance of the transplant lungs in the negative control group was significantly different from that of the autologous lungs, while the transplant lungs in the treatment group were almost identical in color to the autologous lungs compared to the blank control group. Compared with the negative control group, the treatment group showed reduced alveolar exudate and more intact airway epithelial cell structure. No alveolar exudate was observed in the blank control group, and the structure of the airways and alveoli remained normal. The treatment group had lower apoptosis rate of airway epithelial cells, lung tissue wet/dry ratio, and MPO activity compared to the negative control group (all P < 0.05). The levels of IL-6 and TNF-α in the bronchoalveolar lavage fluid of the treatment group were lower than those in the negative control group, while the level of IL-10 was higher than that in the negative control group and the blank control group (all P < 0.05). There were no statistically significant differences in the levels of cytokines in plasma among each group (all P > 0.05). Conclusions UC-MSC may effectively alleviate the severity of primary graft dysfunction in rats by reducing the apoptosis rate of cells in lung tissue and inhibiting inflammatory responses.

Purpose: This Phase II trial was objected to evaluate the efficacy and safety of adding fulvestrant to neoadjuvant chemotherapy in patients with estrogen receptor (ER)+/human epidermal growth factor receptor 2 (HER2)– locally advanced breast cancer (LABC). Additionally, the study aimed to investigate the association of 16α-18F-fluoro-17β-fluoroestradiol (18F-FES) positron emission tomography (PET)–computed tomography (CT) and metabolites with efficacy. Materials and Methods: Fulvestrant and EC-T regimen were given to ER+/HER2– LABC patients before surgery. At baseline, patients received 18F-FES PET-CT scan, and plasma samples were taken for liquid chromatography–mass spectrometry analysis. The primary endpoint was objective response rate (ORR). Secondary endpoints included total pathologic complete response (tpCR) and safety. Results: Among the 36 patients enrolled, the ORR was 86.1%, the tpCR rate was 8.3%. The incidence of grade ≥ 3 treatment-emergent adverse events was 22%. The decrease in ER value in sensitive patients was larger than that in non-sensitive patients, as was Ki-67 (p < 0.05). The maximum standardized uptake value, mean standardized uptake values, total lesion ER expression of 18F-FES PET-CT in sensitive patients were significantly higher than those in non-sensitive patients (p < 0.05). Moreover, these parameters were significantly correlated with Miller and Payne grade and the change in ER expression before and after treatment (p < 0.05). Thirteen differential expressed metabolites were identified, which were markedly enriched in 19 metabolic pathways. Conclusion This regimen demonstrated acceptable toxicity and encouraging antitumor efficacy. 18F-FES PET-CT might serve as a tool to predict the effectiveness of this therapy. Altered metabolites or metabolic pathways might be associated with treatment response.

Purpose: This Phase II trial was objected to evaluate the efficacy and safety of adding fulvestrant to neoadjuvant chemotherapy in patients with estrogen receptor (ER)+/human epidermal growth factor receptor 2 (HER2)– locally advanced breast cancer (LABC). Additionally, the study aimed to investigate the association of 16α-18F-fluoro-17β-fluoroestradiol (18F-FES) positron emission tomography (PET)–computed tomography (CT) and metabolites with efficacy. Materials and Methods: Fulvestrant and EC-T regimen were given to ER+/HER2– LABC patients before surgery. At baseline, patients received 18F-FES PET-CT scan, and plasma samples were taken for liquid chromatography–mass spectrometry analysis. The primary endpoint was objective response rate (ORR). Secondary endpoints included total pathologic complete response (tpCR) and safety. Results: Among the 36 patients enrolled, the ORR was 86.1%, the tpCR rate was 8.3%. The incidence of grade ≥ 3 treatment-emergent adverse events was 22%. The decrease in ER value in sensitive patients was larger than that in non-sensitive patients, as was Ki-67 (p < 0.05). The maximum standardized uptake value, mean standardized uptake values, total lesion ER expression of 18F-FES PET-CT in sensitive patients were significantly higher than those in non-sensitive patients (p < 0.05). Moreover, these parameters were significantly correlated with Miller and Payne grade and the change in ER expression before and after treatment (p < 0.05). Thirteen differential expressed metabolites were identified, which were markedly enriched in 19 metabolic pathways. Conclusion This regimen demonstrated acceptable toxicity and encouraging antitumor efficacy. 18F-FES PET-CT might serve as a tool to predict the effectiveness of this therapy. Altered metabolites or metabolic pathways might be associated with treatment response.

Purpose: This Phase II trial was objected to evaluate the efficacy and safety of adding fulvestrant to neoadjuvant chemotherapy in patients with estrogen receptor (ER)+/human epidermal growth factor receptor 2 (HER2)– locally advanced breast cancer (LABC). Additionally, the study aimed to investigate the association of 16α-18F-fluoro-17β-fluoroestradiol (18F-FES) positron emission tomography (PET)–computed tomography (CT) and metabolites with efficacy. Materials and Methods: Fulvestrant and EC-T regimen were given to ER+/HER2– LABC patients before surgery. At baseline, patients received 18F-FES PET-CT scan, and plasma samples were taken for liquid chromatography–mass spectrometry analysis. The primary endpoint was objective response rate (ORR). Secondary endpoints included total pathologic complete response (tpCR) and safety. Results: Among the 36 patients enrolled, the ORR was 86.1%, the tpCR rate was 8.3%. The incidence of grade ≥ 3 treatment-emergent adverse events was 22%. The decrease in ER value in sensitive patients was larger than that in non-sensitive patients, as was Ki-67 (p < 0.05). The maximum standardized uptake value, mean standardized uptake values, total lesion ER expression of 18F-FES PET-CT in sensitive patients were significantly higher than those in non-sensitive patients (p < 0.05). Moreover, these parameters were significantly correlated with Miller and Payne grade and the change in ER expression before and after treatment (p < 0.05). Thirteen differential expressed metabolites were identified, which were markedly enriched in 19 metabolic pathways. Conclusion This regimen demonstrated acceptable toxicity and encouraging antitumor efficacy. 18F-FES PET-CT might serve as a tool to predict the effectiveness of this therapy. Altered metabolites or metabolic pathways might be associated with treatment response.

OBJECTIVE To compare the efficacy of ceftazidime and avibactam （CZA） monotherapy and combination therapy in the treatment of carbapenem-resistant Gram-negative bacteria （CRGNB） infections， and analyze the influencing factors. METHODS The data of patients with CRGNB infection who received CZA treatment from January 2020 to March 2025 were collected retrospectively. The patients were divided into the CZA monotherapy group （52 cases） and the CZA combination therapy group （85 cases） according to treatment regimen. The therapeutic effects of the two groups were compared， and the drug susceptibility results of isolated strains were recorded. The multivariate Logistic regression model was used to analyze the factors influencing clinical efficacy of CRGNB patients. RESULTS The bacterial clearance rate of patients was significantly higher in the CZA combination therapy group than in the CZA monotherapy group （P＝0.012）. However， when comparing the 30-day mortality rate and the clinical response rate between the two groups， no statistically significant differences were observed （P＞0.05）. Among the isolates， carbapenem-resistant Klebsiella pneumoniae had the highest sensitivity to tigecycline （87.3%） and carbapenem-resistant Pseudomonas aeruginosa showed 90.9% sensitivity to amikacin. Five isolates were resistant to CZA. The multivariate Logistic regression showed， lung infection， receiving continuous renal replacement therapy （CRRT）， and inadequate treatment courses were significantly correlated with clinical treatment failure （P＜0.05）. CONCLUSIONS For CRGNB infection， the clinical efficacy of CZA combination therapy is similar to that of monotherapy， but the combination therapy has a higher bacterial clearance rate. Lung infections， receiving CRRT and inadequate treatment courses （No. are independent risk factors for clinical treatment failure.

ObjectiveTo explore the impact of Gegen Qinliantang（GQT） on the fecal short-chain fatty acids（SCFAs） metabolism in antibiotic-associated diarrhea（AAD） through targeted metabolomics. MethodA total of 240 SD rats were randomly divided into six groups（n=40， half male and half female）， including blank group， model group， bifidobiogen group（0.15 g·kg^-1）， and GQT high-， medium-， and low-dose groups（10.08， 5.04， 2.52 g·kg^-1）， except for the blank group， clindamycin（250 mg·kg^-1） was given to all groups by gavage for modeling every day for 7 d. After successful modeling， each administered group was gavaged with the corresponding dose of the drug， and the blank and model groups were gavaged with an equal volume of normal saline solution， 1 time/d， for 14 d. At 0， 3， 7， 14 d after the drug intervention， eight rats were randomly selected from each group， respectively. Gas chromatography-time-of-flight mass spectrometry（GC-TOF-MS） was used to perform targeted metabolomic analysis of SCFAs in the feces of rats， and partial least squares-discriminant analysis（PLS-DA） was applied to compare the differences in metabolic profiles between groups at different treatment times， and to compare the changes in the contents of SCFAs in rat feces between groups. ResultPLS-DA results showed that the blank group could be clearly distinguishable from the model group， with GQT exhibiting a closer proximity to the blank group after 7 d of treatment. After further analyzing the composition of SCFAs， it was found that the proportion of acetic acid increased and the proportions of butyric acid， valeric acid， hexanoic acid and isovaleric acid decreased in the model group compared with the blank group. After the treatment with GQT， the proportions of butyric acid， isobutyric acid， valeric acid， and isovaleric acid increased， and the proportions of acetic acid， propionic acid and caproic acid decreased. Subsequent differential analysis revealed that GQT could significantly improve the content of butyric acid， and had a certain retrogressive effect on the contents of valeric acid and hexanoic acid. ConclusionThe medium dose group of GQT can improve the contents of SCFAs in AAD feces after 7 days of treatment， which may be related to the improvement of the composition ratio of SCFAs and the contents of butyric acid， valeric acid and caproic acid.

Objective: To explore the relationship between the ratio of dietary vitamin A (VitA) to body weight and hypertension among children, so as to provide a reference for blood pressure control through dietary nutritional interventions and childhood hypertension prevention. Methods: Utilizing the baseline survey and followup sample data from the Healthy Children Cohort established in urban and rural areas of Chongqing from 2014 to 2019, structured quantitative dietary questionnaire and selfdesigned questionnaire were used to investigate the information of dietary intake and socioeconomic characteristics of 15 279 children, as well as blood pressure, height, weight measurement. The ratio of dietary VitA to body weight was divided into four groups based on quartiles [≤P25(Q1), >P25~P50(Q2), >P50~P75(Q3), >P75(Q4)]. Generalized linear regression models and Logistic regression models were used to analyze the correlation between ratio of dietary VitA to body weight with blood pressure levels and prevalence of hypertension. Results: The results of the 2014 baseline survey indicated that, after adjusting for confounding factors such as demographic indicators and nutritional intake, significant differences were observed in systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) among different groups categorized by the ratio of dietary VitA to body weight (F=157.57, 44.71, 95.92, P<0.01). The baseline ratio of dietary VitA to body weight in children exhibited a negative correlation with DBP, SBP and MAP at baseline and in 2019[baseline: β(95%CI)=-0.65(-0.89--0.42), -0.22(-0.42--0.01), -0.36(-0.56--0.16); 2019: β(95%CI)=-0.77(-1.34--0.19), -0.62(-1.21--0.02), -0.77(-1.34--0.19), P＜0.05]. Compared to Q1 group, the risk of hypertension decreased among children in Q4 at baseline and followup in 2019 [OR(95%CI)=0.63(0.49-0.81), 0.18(0.08-0.42), P<0.01]. Conclusions The ratio of dietary VitA to body weight is significantly negatively correlated with blood pressure levels among children, and dietary VitA deficiency is an independent risk factor for hypertension among children. Measures should be taken to actively adjust childrens dietary nutrition and reduce the risk of childhood hypertension.

The Hedgehog （Hh） signaling pathway plays an important role in the development and progression of hepatocellular carcinoma and its tumor microenvironment， and abnormal activation of Hh signal can accelerate the growth of tumor. The crosstalk between the Hh signaling pathway and TME is closely associated with tumor growth and the formation of inhibitory tumor microenvironment. Evidence shows that inhibition of Hh signal plays an important role in inhibiting the growth of hepatocellular carcinoma. This article reviews the current research status of the role， mechanism， and potential therapeutic significance of abnormal activation of Hh signal in hepatocellular carcinoma and its tumor microenvironment， so as to provide new ideas for the treatment of hepatocellular carcinoma.

Objective To evaluate clinical efficacy of lung transplantation for lung chronic graft-versus-host disease (cGVHD) after hematopoietic stem cell transplantation (HSCT). Methods Clinical data of 12 patients undergoing lung transplantation for lung cGVHD were retrospectively analyzed. Preoperative clinical manifestations and involved organs of patients were analyzed. The lung function before and after lung transplantation was compared, and the survival of patients after lung transplantation was analyzed. Results Eleven patients underwent HSCT due to primary hematological malignancies, including 9 cases of leukemia, 1 case of myelodysplastic syndrome, 1 case of lymphoma. And 1 case underwent HSCT for systemic lupus erythematosus. Among 12 cGVHD patients, skin involvement was found in 8 cases, oral cavity involvement in 5 cases, gastrointestinal tract involvement in 4 cases and liver involvement in 3 cases. All 12 patients developed severe respiratory failure caused by cGVHD before lung transplantation, including 9 cases of typeⅡ respiratory failure and 3 cases of type Ⅰ respiratory failure. Two patients underwent right lung transplantation, 2 cases of left lung transplantation and 8 cases of bilateral lung transplantation. The interval from HSCT to lung transplantation was 75 (19-187) months. Upon the date of submission, postoperative follow-up time was 18 (7-74) months. Ten patients survived, 1 died from severe hepatitis at postoperative 22 months, and 1 died from gastrointestinal bleeding at postoperative 6 months. No recurrence of primary diseases was reported in surviving patients. Conclusions Lung transplantation is an efficacious treatment for lung cGVHD after HSCT, which may prolong the survival time and improve the quality of life of the recipients.