Background Toluene and chlorobenzene have been designated as surrogate contaminants in the challenge test for evaluating the safety of recycling processes for food-contact recycled polyethylene terephthalate (rPET). Establishing a reliable analytical method is essential for ensuring the compliant use of rPET and safeguarding food safety. Objective To develop a rapid quantitative method for determining toluene and chlorobenzene in rPET using headspace gas chromatography-mass spectrometry (HS-GC-MS), as part of the challenge test for process safety evaluation. Methods The effects of different chromatographic columns and headspace conditions on detection of target analytes were investigated. Three columns HP-5 ms UI (30 m×0.25 mm×0.25 μm), DB-624 (30 m×0.32 mm×1.8 μm), and VF-WAXms (30 m×0.25 mm×0.25 μm) were compared for separation efficiency and peak shape. Headspace equilibration temperatures (50-100 ℃) and equilibration times (10-30 min) were evaluated to determine the optimal instrumental parameters. The effect of sample grinding on recovery was assessed to select the best pretreatment conditions. The established method was validated for selectivity, linearity, sensitivity, accuracy, and precision, and was subsequently applied to the analysis of 12 rPET samples. Results The target analytes achieved good separation and response within 15 min, under the optimized conditions using an HP-5 ms UI column, a headspace equilibration temperature of 60 ℃ and a 10 min equilibration time. Direct analysis without grinding yielded satisfactory recovery rates. Toluene and chlorobenzene showed excellent linearity (0.0030-5.0 mg·kg⁻¹, R²≥0.999). The limits of detection (LOD) and quantification (LOQ) were 0.00003 mg·kg⁻¹ and 0.00011 mg·kg⁻¹ for toluene respectively, and 0.00011 mg·kg⁻¹ and 0.00037 mg·kg⁻¹ for chlorobenzene respectively. The recoveries of the matrix spike at low and high spiking levels ranged from 88.6% to 110%, with relative standard deviations of 0.52%-4.9% (n=6). Among the 12 rPET samples from different recycling stages, three samples contained detectable levels of toluene (0.196-0.250 mg·kg⁻¹) and chlorobenzene (0.704-0.867 mg·kg⁻¹). Conclusion The proposed method is simple, rapid, highly sensitive, and accurate, making it suitable for determining toluene and chlorobenzene in food-contact rPET. It provides a robust technical approach for the safety evaluation of rPET recycling processes.

ObjectiveTo explore the effect of modified Ditan Decoction （涤痰汤） on chronic intermittent hypoxia cognitive function and the potential function mechanism. MethodsTwenty-four Sprague-Dawley （SD） rats were randomly divided into a normal group， a model group， and a modified Ditan Decoction group， with eight rats in each group. Rats in the modified Ditan Decoction group were administered the decoction by gavage at 14.8 ml/（kg·d）， while the normal group and the model group received the same dose of normal saline. Thirty minutes after daily gavage， the rats in all three groups were placed in an intermittent hypoxia chamber. The oxygen concentration for the model group and the modified Ditan Decoction group was adjusted daily for 8 hours using a computer program to establish the model， while the normal group was exposed to the same airflow rate of ambient air. The intervention was continued for 12 weeks to establish a chronic intermittent hypoxia rat model. The Y-maze test was used to evaluate spatial working memory in the rats. Resting-state functional magnetic resonance imaging （rs-fMRI） was performed to detect whole-brain regional homogeneity （ReHo） and seed-based functional connectivity （FC）. Brain regions showing significant differences in rs-fMRI were selected for further analysis. Immunofluorescence was used to detect β-amyloid （Aβ） deposition and the number of ionized calcium-binding adapter molecule 1 （IBA1）-positive microglial cells. Immunohistochemistry was employed to assess the expression of synaptophysin （SYP）， the excitatory synapse marker vesicular glutamate transporter 1 （Vglut1）， and the inhibitory synapse marker vesicular γ-aminobutyric acid transporter （VGAT）. ResultsCompared with the normal group， the model group showed a reduced spontaneous alternation rate in the Y-maze test. The smoothed Z-score standardized regional homogeneity （SzReHo） value in the left entorhinal cortex significantly increased， and the FC value from this seed point to the left basal forebrain significantly reduced. Additionally， the model group exhibited significantly higher Aβ fluorescence intensity and Iba1 positivity in the left entorhinal cortex， decreased expression of SYP， Vglut1， and VGAT， along with an increased Vglut1/VGAT ratio （P＜0.05 or P＜0.01）. Compared to the model group， the modified Ditan Decoction group demonstrated an increased spontaneous alternation rate， a significantly reduced SzReHo value in the left entorhinal cortex， and a significantly increased FC value from this region to the left basal forebrain. Furthermore， this group showed significantly lower Aβ fluorescence intensity and Iba1 positivity in the left entorhinal cortex， increased levels of SYP， Vglut1， and VGAT， and a decreased Vglut1/VGAT ratio （P＜0.05 or P＜0.01）. ConclusionModified Ditan Decoction can reconstruct the projection from the left basal forebrain to the entorhinal cortex in chronic intermittent hypoxia， thereby reducing Aβ aggregation and excessive microglial activation in the left entorhinal cortex. This process improves the excitation/inhibition imbalance caused by synaptic remodeling， ultimately enhancing cognitive function in rats of chronic intermittent hypoxia.

Objective: To investigate the regional differences in the incidence of urothelial carcinoma among kidney transplant recipients between northern and southern China，so as to provide reference for early diagnosis of this disease. Methods: A comprehensive search was conducted across multiple databases，including CNKI，Wanfang，CBM，and PubMed，using the keywords “kidney transplantation” and “tumor” to collect clinical data from qualified kidney transplant centers.The latest and most complete literature data published by 17 transplant centers in northern China and 14 in southern China were included.Statistical analyses were performed to compare the incidence of post-transplant urothelial carcinoma and non-urothelial malignancies. Results: A total of 37 475 kidney transplant recipients were included，among whom 837 (2.23%) developed post-transplant malignancies，including urothelial carcinoma (366/837，43.73%)，non-urothelial carcinoma (444/837，53.05%)，and malignancies with unspecified pathology (27/837，3.23%).The incidence of malignancies was significantly higher in northern China than in southern China [(2.82±1.39)% vs. (1.67±0.83)%，P=0.011]，with a particularly pronounced difference in the incidence of urothelial carcinoma [(1.68±1.12)% vs. (0.32±0.32)%，P<0.001].No significant difference was observed in the incidence of non-urothelial carcinoma between the two regions [(1.11±0.56)% vs. (1.35±0.65)%，P=0.279].Additionally，female transplant recipients exhibited a higher incidence of malignancies than males in both regions (southern China：2.38% vs. 1.80%; northern China：8.93% vs. 2.52%). Conclusion: The incidence of urothelial carcinoma following kidney transplantation is significantly higher in northern China than in southern China，underscoring the importance of implementing regular tumor screening for kidney transplant recipients，particularly for female patients in northern China，to facilitate early diagnosis and timely intervention.

Objective: To investigate the characteristics of malignant tumor incidence and mortality in cancer registration areas of Zhejiang Province in 2021. Methods: Based on the 2021 cancer registration data from 22 national cancer registries in Zhejiang Province, the crude incidence, crude mortality, and cumulative rate for 0 to 74 years were calculated. Age standardized was performed using the age composition of the standard population from the Fifth National Population Census in 2000 and Segi's world standard population. The incidence and mortality characteristics of malignant tumor in different genders, urban/rural areas and ages were described. The order of crude incidence and mortality of malignant tumor were analyzed. Results: In 2021, there were 116 639 new malignant tumor cases in Zhejiang Province. The crude, Chinese population standardized, and world population-standardized incidences were 530.93/100 000, 304.83/100 000, and 288.20/100 000, respectively. The cumulative incidence for 0 to 74 years was 31.92%. There were 40 475 death cases. The crude, Chinese population-standardized, and world population-standardized mortalities were 184.24/100 000, 79.40/100 000, and 78.97/100 000, respectively. The cumulative mortality for 0 to 74 years was 8.37%. The Chinese population-standardized incidence for males and females were 286.34/100 000 and 323.45/100 000, respectively, and the Chinese population-standardized mortality were 106.25/100 000 and 54.17/100 000, respectively. The Chinese population-standardized incidence for urban and rural were 316.85/100 000 and 285.11/100 000, respectively, and the Chinese population-standardized mortality were 75.59/100 000 and 85.48/100 000, respectively. The crude incidence and crude mortality of malignant tumor both increased with age, peaking in the groups aged 80-<80 and ≥85 years at 1 845.06/100 000 and 1 656.88/100 000, respectively. The top ten malignant tumors with the highest crude incidence were, in descending order: lung cancer, thyroid cancer, breast cancer, prostate cancer, colorectal cancer, gastric cancer, liver cancer, cervical cancer, lymphoma, and brain tumors. These accounted for 80.34% of all new malignant tumor cases. The top ten malignant tumors with the highest crude mortality were, in descending order: lung cancer, liver cancer, colorectal cancer, gastric cancer, pancreatic cancer, prostate cancer, breast cancer, esophageal cancer, lymphoma, and gallbladder cancer. These accounted for 82.26% of all malignant tumor deaths. Conclusions In 2021, the cancer registration areas of Zhejiang Province were characterized by a relatively high malignant tumor incidence and a comparatively low mortality compared to national data. Males and the elderly emerged as key populations for targeted prevention and control. It is recommended to enhance screening, early diagnosis, and early treatment for lung cancer, thyroid cancer, prostate cancer, breast cancer, and gastric cancer malignancies.

Objective:To investigate the sero-conversion rate of HIV antibody and influencing factors in cross-border couples in Dehong Dai and Jingpo Autonomous Prefecture(Dehong).Methods:A cohort design was used to recruit HIV-negative people in cross-border couples in Dehong in 2017. Follow-up was conducted in 2023, and questionnaire survey and HIV test were carried out to calculate the sero-conversion rate of HIV antibody. Univariate and multivariate logistic regression models were used to analyze the influence factors for HIV infections.Results:A total of 36 278 HIV-negative persons in cross-border couples were included in the 2017 baseline survey, of whom 22 438 (61.9%) were tested in follow-up in 2023. The sero-conversion rate between 2017 and 2023 was 0.51% (115/22 438). Multivariate logistic regression analysis showed that length of marriage <6 years, Jingpo ethnic group, education level of primary school or below, drug use, illegal marriage and HIV infected spouse were the risk factors of HIV infection in male spouses, and length of marriage <6 years, Jingpo ethnic group, illegal marriage and HIV infected spouse were the risk factors in female spouses.Conclusions:The sero-conversion rate of HIV antibody in cross-border couples in Dehong was relatively high. HIV infection was mainly caused by secondary transmission in the couples, and men might also be infected through drug use. It is necessary to strengthen the registration and management of cross-border couples, especially the couples with discordant HIV infection status, and the intervention in drug users to reduce the risk for secondary transmission of HIV in the cross-border couples.

Objective:To investigate the influencing factors of enlarged perivascular space (PVS) in relapsing-remitting multiple sclerosis (RRMS) patients and their relationship with cognitive function.Methods:Twenty-seven individuals with RRMS (RRMS group) and 27 healthy controls (healthy control group) who presented to the Department of Neurology, the Sixth Medical Center of People′s Liberation Army General Hospital from July 2022 to November 2024 underwent cognitive function assessments. PVS volume fractions, lesion volumes, and brain volumes were calculated using FreeSurfer, FSL, and other relevant softwares. Group differences in PVS volume fractions, lesion volumes, brain volumes, and cognitive function assessments were compared. Furthermore, correlations between PVS volume fractions and lesion volumes, brain volumes, and cognitive function assessments were analyzed within the RRMS group.Results:Compared with the healthy control group, the RRMS group exhibited significantly higher PVS volume fractions in white matter (PVS_w) (3.14‰±0.29‰ vs 2.91‰±0.30‰, t=2.877, P=0.006) and PVS volume fractions in deep gray matter (PVS_d) (2.25‰±0.10‰ vs 2.17‰±0.09‰, t=2.681, P=0.010), indicating an enlargement of the PVS. Compared with the healthy control group, the RRMS group showed a significant decrease in both white matter volumes [297.3 (274.3, 340.2) ml vs (324.2 (311.0, 350.0) ml, U=-2.085, P=0.037] and deep grey matter volumes [40.2 (34.9, 43.6) ml vs 42.7 (40.2, 44.8) ml, U=-2.292, P=0.022]. Compared with the healthy control group, the RRMS group showed significantly lower scores in cognitive function assessments ( P<0.05). Univariate analysis showed that PVS_w in the RRMS group was significantly positively correlated with age ( r=0.486), white matter lesion volumes ( r=0.437) and deep gray matter lesion volumes ( r=0.394;all P<0.05); PVS_d was also significantly positively correlated with white matter lesion volumes ( r=0.418) and deep gray matter lesion volumes ( r=0.480; both P<0.05). Multiple linear regression analysis showed that age ( B=0.011,95% CI 0.004-0.017), white matter lesion volumes ( B=0.026,95% CI 0.011-0.040) and deep gray matter lesion volumes ( B=0.401,95% CI 0.032-0.771) in the RRMS group were significantly positively correlated with PVS_w, while white matter lesion volumes ( B=0.007,95% CI 0.001-0.014) and deep gray matter lesion volumes ( B=0.204,95% CI 0.029-0.380) were significantly positively correlated with PVS_d (both P<0.05). Univariate analysis showed that immediate memory score in the RRMS group was significantly negatively correlated with PVS_d ( r=-0.428), and was significantly positively correlated with education level ( r=0.471), deep gray matter volumes ( r=0.530) and total brain volumes ( r=0.389; all P<0.05); short-term delayed memory score in the RRMS group was significantly negatively correlated with age ( r=-0.390), PVS_w ( r=-0.417) and white matter lesion volumes ( r=-0.438), and was significantly positively correlated with gender ( r=0.393), white matter volumes ( r=0.478), deep gray matter volumes ( r=0.579) and total brain volumes ( r=0.602;all P<0.05); verbal fluency test score in the RRMS group was significantly negatively correlated with PVS_d ( r=-0.409) and was significantly positively correlated with education level ( r=0.419) and total brain volumes ( r=0.400;all P<0.05). Multiple linear regression analysis revealed that PVS_d ( B=-5.572, 95% CI -11.513--0.368) and brain volumes ( B=0.012, 95% CI 0.001-0.023) in the RRMS group were both significant predictors of immediate recall score, while PVS_d ( B=-14.203,95% CI -27.514--0.891) was an independent predictor of verbal fluency test score (all P<0.05). Conclusions:The PVS is enlarged in individuals with RRMS compared with the healthy controls, and increased lesion volumes may be a significant predictor. Furthermore, enlarged PVS in the deep gray matter may be a significant predictor of impairment of verbal memory and verbal function in individuals with RRMS.

Objective:To explore the effects and prognosis of heavy ion therapy for thoracic and abdominal malignant tumors under different frequency settings of high-frequency oscillatory breathing control.Methods:A prospective randomized controlled trial was conducted on 45 patients with thoracic and abdominal malignant tumors who received heavy ion therapy under high-frequency oscillatory ventilation (HFOV) control at Gansu Wuwei Tumour Hospital from January 2023 to December 2024. The patients were randomly divided into three groups by block randomization, with 15 patients in each group, and they received different HFOV frequency settings (6 Hz, 7 Hz and 8 Hz, i.e., 360 breaths/min, 420 breaths/min and 480 breaths/min), while other parameters were kept constant (oxygen concentration: 40%, mean airway pressure: 10 cmH 2O, amplitude: 6cm). The arterial blood gas, transcutaneous carbon dioxide partial pressure/transcutaneous oxygen partial pressure (TcPCO 2/TcPO 2), duration of HFOV ventilation, duration of invasive mechanical ventilation, length of hospital stay and complications of the patients under different frequency settings were analyzed. Results:Before and after treatment, there was no statistically significant difference in arterial blood gas parameters (PaCO 2, PaO 2), oxygenation index, blood lactate, bicarbonate ion) among the 6 Hz,7 Hz and 8 Hz HFOV frequency groups (all P＞0.05). At 30 minutes, 60 minutes, 120 minutes of treatment and at extubation, there was no statistically significant difference in TcPCO 2, TcPO 2, SpO 2 and heart rate among the 6 Hz, 7 Hz and 8 Hz HFOV frequency groups (all P＞0.05). The HFOV duration of the 6 Hz, 7 Hz and 8 Hz HFOV frequency groups was (131.7±8.4) minutes, (125.3±6.9) minutes and (115.7±10.5) minutes, respectively; the duration of invasive mechanical ventilation was (212.3±21.2) minutes, (190.7±14.8) minutes and (199.3±18.4) minutes, respectively; the tumor shrinkage rate was (53.1±6.1)%, (64.7±5.1)% and (63.0±6.2)%, respectively; and the hospital stay was (22.7±2.9) days, (22.3±3.1) days and (20.8±3.3) days, respectively. There was no statistically significant difference among the groups (all P＞0.05). Only one patient developed reversible hypercapnia, which returned to the normal range within 30 minutes after adjusting the invasive ventilator parameters. No treatment-related adverse events such as hypoxemia, radiation pneumonitis, or hemodynamic instability occurred in any of the subjects. Conclusions:HFOV management under heavy ion therapy for thoracoabdominal malignancies shows no significant changes in arterial blood gas analysis before and after treatment at different frequencies (6 Hz, 7 Hz, 8 Hz). Continuous monitoring of transcutaneous TcPCO 2/TcPO 2 is stable. The treatment process is safe, with few complications and good results.

Objective To explore the value of quantitative analysis of perirenal fat combined with Mayo adhesive probability(MAP)score in predicting the WHO/International Society of Urological Pathology(ISUP)nuclear grade of renal cell carcinoma(RCC).Methods The imaging data of 139 pathologically confirmed RCC patients were retrospectively analyzed.The patients were divided into low-grade group(grade Ⅰ-Ⅱ,n=112)and high-grade group(grade Ⅲ-Ⅳ,n=27)according to the WHO/ISUP nuclear grade.Spearman correlation analysis was used to assess the relationship between fat features and WHO/ISUP nuclear grade.The multivariate logistic regression model was used to detemine the related factors of high-grade RCC,and the area under the curve(AUC)of the receiver operating characteristic(ROC)curve was used to evaluate the diagnostic performance of each parameter.Results The AUC of perirenal adipose tissue(PAT)％alone for evaluating high-grade RCC was the highest,at 0.77[95％confidence interval(CI)0.69-0.83].The stepwise multivariate logistic regression model showed that perinephric fat stranding(PFS)[odds ratio(OR)=34.54,95％CI 7.60-156.87,P＜0.001],PAT％(OR=0.46,95％CI 0.32-0.66,P＜0.001),and tumor location(OR=0.26,95％CI 0.07-0.92,P=0.037)were related factors of high-grade RCC,with an AUC of 0.90(95％CI 0.84-0.94).Conclusion Quantitative analysis of perire-nal fat combined with MAP score can effectively predict the WHO/ISUP nuclear grade of RCC,providing a novel approach for per-sonalized treatment strategies to improve prognosis.

AIM:To investigate the effects of nebulized sodium tanshinone ⅡA sulfonate(STS)in a mouse model of pulmonary hypertension associated with chronic obstructive pulmonary disease(COPD-PH).METHODS:A to-tal of 32 healthy SPF-grade male C57BL/6 mice were randomly divided into 4 groups:control(CTL,n=8)group,COPD-PH(CS+LPS,n=8)group,STS-treated COPD-PH(CS+LPS+STS,n=8)group,and STS(n=8)group.The COPD-PH model was established through whole-body exposure to cigarette smoke(CS)combined with lipopolysaccharide(LPS)in-halation.Mice were subjected to cigarette smoke exposure in a chamber(9 cigarettes/h,2 h/session,2 sessions/d,6 d/week)for 60 d,except on days of LPS inhalation.On days 1 and 14,COPD-PH model mice received LPS(7.5 μg/mouse in 50 μL saline)via intranasal inhalation,while the CTL and STS groups received an equivalent volume of saline.STS was administered via nebulized inhalation(5 mg/kg,30 min per session,twice daily)immediately before CS exposure.At the end of the modeling period,lung function and right heart pressure were assessed.Bronchoalveolar lavage fluid(BALF)was collected for inflammatory cell counting.Levels of interleukin-6(IL-6)in BALF supernatants and plasma were measured using ELISA.Pathological changes in the airway and lung tissues were evaluated.RESULTS:(1)Com-pared to CTL mice,those exposed to CS and LPS exhibited lesions characteristic of COPD-PH,including emphysema,lung inflammation,decreased lung function,and increased right ventricular systolic pressure(RVSP)and right ventricu-lar hypertrophy index(RVHI)(P<0.05);(2)COPD-PH mice showed significantly elevated IL-6 levels in both BALF and plasma(P<0.05);(3)STS treatment alleviated emphysema and lung inflammation,improved lung function,prevent-ed increases in RVSP and the RV/(LV+S)ratio,and reduced IL-6 levels in both BALF and plasma(P<0.05).CON-CLUSION:The results indicate that nebulized inhalation of STS significantly slows the progression of COPD-PH,likely due to its ability to inhibit lung inflammation and reduce IL-6 expression in the lungs.

Objective:To investigate the sero-conversion rate of HIV antibody and influencing factors in cross-border couples in Dehong Dai and Jingpo Autonomous Prefecture(Dehong).Methods:A cohort design was used to recruit HIV-negative people in cross-border couples in Dehong in 2017. Follow-up was conducted in 2023, and questionnaire survey and HIV test were carried out to calculate the sero-conversion rate of HIV antibody. Univariate and multivariate logistic regression models were used to analyze the influence factors for HIV infections.Results:A total of 36 278 HIV-negative persons in cross-border couples were included in the 2017 baseline survey, of whom 22 438 (61.9%) were tested in follow-up in 2023. The sero-conversion rate between 2017 and 2023 was 0.51% (115/22 438). Multivariate logistic regression analysis showed that length of marriage <6 years, Jingpo ethnic group, education level of primary school or below, drug use, illegal marriage and HIV infected spouse were the risk factors of HIV infection in male spouses, and length of marriage <6 years, Jingpo ethnic group, illegal marriage and HIV infected spouse were the risk factors in female spouses.Conclusions:The sero-conversion rate of HIV antibody in cross-border couples in Dehong was relatively high. HIV infection was mainly caused by secondary transmission in the couples, and men might also be infected through drug use. It is necessary to strengthen the registration and management of cross-border couples, especially the couples with discordant HIV infection status, and the intervention in drug users to reduce the risk for secondary transmission of HIV in the cross-border couples.