1.A Computational Perspective on Differences Between MHC-I and MHC-II in TCR-pMHC Structure Prediction Resources: Review and Benchmarking
Xiao-Qin WU ; Da-Wei LIU ; Bin-Yu LI ; Yang LIU ; Yang CAO ; Wen-Tao DAI
Progress in Biochemistry and Biophysics 2026;53(5):1376-1399
The initiation of adaptive immune responses relies on the precise recognition and interpretation of antigenic information. In this process, the specific binding of T cell receptors (TCRs) to peptide-major histocompatibility complex (pMHC) molecules represents one of the key molecular events in the initiation of adaptive immune responses. Accordingly, the structural features of TCR-pMHC complexes provide a fundamental basis for dissecting antigen recognition mechanisms and support rational vaccine design, therapeutic target discovery in TCR-based immunotherapy, and TCR identification and optimization. However, experimental determination of TCR-pMHC structures remains costly, time-consuming, and limited in coverage, making computational approaches essential for rapidly obtaining reliable structural information. Computational methods for predicting the structures of TCR-pMHC complexes have advanced rapidly in recent years, driven by progress in deep learning-based modeling frameworks and the increasing availability of structural and sequence resources. Despite these developments, most existing tools do not adequately distinguish the key structural and biophysical differences between MHC class I (MHC-I) and MHC class II (MHC-II) complexes during model construction. As a consequence, their predictive performance differs substantially between class I and class II complexes. In general, structural predictions for class I complexes outperform those for class II complexes. This discrepancy may be related to several fundamental differences between the two systems, including the architecture of the peptide-binding groove, the distribution of peptide lengths, and the properties of peptide flanking residues (PFRs). Compared with MHC-I molecules, MHC-II molecules usually bind longer antigenic peptides, which typically range from 13 to 25 amino acids in length. PFRs at both termini of these peptides participate in regulating the overall conformation of TCR-pMHC class II complexes and exert a pronounced effect on the geometric and physicochemical characteristics of the TCR-pMHC binding interface. Furthermore, within the TCR recognition interface, the complementarity-determining regions (CDRs) consist of segments that differ markedly in conformational behavior. They commonly include regions that are relatively rigid and structurally stable, together with highly flexible segments exhibiting substantial conformational plasticity. These rigidity-flexibility features constitute an essential structural basis enabling TCRs to recognize diverse peptide-MHC ligands and to accommodate conformational heterogeneity at the interface. However, many current modeling tools, in an effort to enforce global conformational stability or reduce structural noise, tend to over-constrain intrinsically flexible regions. Such oversimplification may lead to inappropriate rigidification of flexible CDR loops, resulting in local structural distortions, compromised interface geometry, or even complete modeling failure for specific complexes. Against this background, the review approaches the field from the perspective of computational differences between MHC-I and MHC-II complexes. We first systematically organize and summarize available resources related to TCRs and pMHCs, including structural datasets, sequence databases, prediction tools, and benchmarking studies. We then focus on five representative tools capable of predicting both class I and class II complexes—AlphaFold2, AlphaFold3, TCRmodel2, tFold-TCR, and TCR-pHLA_ModellerS. After excluding structures present in the training sets of these tools, we constructed a benchmark dataset comprising 25 class I and 10 class II TCR-pMHC complexes in the bound state and conducted a systematic evaluation using this dataset. We first employ widely used general evaluation metrics, including All-Atom Root Mean Square Deviation (All-Atom RMSD), Backbone RMSD, Template Modeling score (TM-score), and DockQ, to assess the global conformational accuracy and interface modeling quality of class I and class II complexes. For class II complexes, we propose for the first time a peptide flanking residue deviation index, including the PFRs-Deviation Index (PFRs-DI), N-PFR-Deviation Index (N-PFR-DI), and C-PFR-Deviation Index (C-PFR-DI), to quantitatively characterize conformational deviations in PFRs. In addition, we propose the CDR conformational consistency index (CCC) designed to qualitatively evaluate the ability of prediction tools to capture TCR CDR conformational flexibility. These metrics collectively assess a tool’s ability to model both overall conformation and critical functional regions, thereby addressing the limitations of existing evaluation criteria that overemphasize global structure while inadequately capturing modeling quality in key functional areas. This establishes a unified analytical framework for MHC-I and MHC-II complexes to guide data resource selection, modeling strategy formulation, and evaluation system development. The framework further advances computational modeling and provides crucial support for multi-scale analysis of TCR-pMHC recognition mechanisms and their biological functions.
2.A Computational Perspective on Differences Between MHC-I and MHC-II in TCR-pMHC Structure Prediction Resources: Review and Benchmarking
Xiao-Qin WU ; Da-Wei LIU ; Bin-Yu LI ; Yang LIU ; Yang CAO ; Wen-Tao DAI
Progress in Biochemistry and Biophysics 2026;53(5):1376-1399
The initiation of adaptive immune responses relies on the precise recognition and interpretation of antigenic information. In this process, the specific binding of T cell receptors (TCRs) to peptide-major histocompatibility complex (pMHC) molecules represents one of the key molecular events in the initiation of adaptive immune responses. Accordingly, the structural features of TCR-pMHC complexes provide a fundamental basis for dissecting antigen recognition mechanisms and support rational vaccine design, therapeutic target discovery in TCR-based immunotherapy, and TCR identification and optimization. However, experimental determination of TCR-pMHC structures remains costly, time-consuming, and limited in coverage, making computational approaches essential for rapidly obtaining reliable structural information. Computational methods for predicting the structures of TCR-pMHC complexes have advanced rapidly in recent years, driven by progress in deep learning-based modeling frameworks and the increasing availability of structural and sequence resources. Despite these developments, most existing tools do not adequately distinguish the key structural and biophysical differences between MHC class I (MHC-I) and MHC class II (MHC-II) complexes during model construction. As a consequence, their predictive performance differs substantially between class I and class II complexes. In general, structural predictions for class I complexes outperform those for class II complexes. This discrepancy may be related to several fundamental differences between the two systems, including the architecture of the peptide-binding groove, the distribution of peptide lengths, and the properties of peptide flanking residues (PFRs). Compared with MHC-I molecules, MHC-II molecules usually bind longer antigenic peptides, which typically range from 13 to 25 amino acids in length. PFRs at both termini of these peptides participate in regulating the overall conformation of TCR-pMHC class II complexes and exert a pronounced effect on the geometric and physicochemical characteristics of the TCR-pMHC binding interface. Furthermore, within the TCR recognition interface, the complementarity-determining regions (CDRs) consist of segments that differ markedly in conformational behavior. They commonly include regions that are relatively rigid and structurally stable, together with highly flexible segments exhibiting substantial conformational plasticity. These rigidity-flexibility features constitute an essential structural basis enabling TCRs to recognize diverse peptide-MHC ligands and to accommodate conformational heterogeneity at the interface. However, many current modeling tools, in an effort to enforce global conformational stability or reduce structural noise, tend to over-constrain intrinsically flexible regions. Such oversimplification may lead to inappropriate rigidification of flexible CDR loops, resulting in local structural distortions, compromised interface geometry, or even complete modeling failure for specific complexes. Against this background, the review approaches the field from the perspective of computational differences between MHC-I and MHC-II complexes. We first systematically organize and summarize available resources related to TCRs and pMHCs, including structural datasets, sequence databases, prediction tools, and benchmarking studies. We then focus on five representative tools capable of predicting both class I and class II complexes—AlphaFold2, AlphaFold3, TCRmodel2, tFold-TCR, and TCR-pHLA_ModellerS. After excluding structures present in the training sets of these tools, we constructed a benchmark dataset comprising 25 class I and 10 class II TCR-pMHC complexes in the bound state and conducted a systematic evaluation using this dataset. We first employ widely used general evaluation metrics, including All-Atom Root Mean Square Deviation (All-Atom RMSD), Backbone RMSD, Template Modeling score (TM-score), and DockQ, to assess the global conformational accuracy and interface modeling quality of class I and class II complexes. For class II complexes, we propose for the first time a peptide flanking residue deviation index, including the PFRs-Deviation Index (PFRs-DI), N-PFR-Deviation Index (N-PFR-DI), and C-PFR-Deviation Index (C-PFR-DI), to quantitatively characterize conformational deviations in PFRs. In addition, we propose the CDR conformational consistency index (CCC) designed to qualitatively evaluate the ability of prediction tools to capture TCR CDR conformational flexibility. These metrics collectively assess a tool’s ability to model both overall conformation and critical functional regions, thereby addressing the limitations of existing evaluation criteria that overemphasize global structure while inadequately capturing modeling quality in key functional areas. This establishes a unified analytical framework for MHC-I and MHC-II complexes to guide data resource selection, modeling strategy formulation, and evaluation system development. The framework further advances computational modeling and provides crucial support for multi-scale analysis of TCR-pMHC recognition mechanisms and their biological functions.
3.Development and Validation of a High-Performance Liquid Chromatography-Tandem Mass Spectrometry Method for Detecting Adrenocortical Hormones and Establishment of Age-Stratified Reference Intervals in Reproductive-Aged Women from Guangxi, China
Yixuan LIU ; Tingwei JIN ; Yushuang WEI ; Xuelian QIN ; Siyu DENG ; Jie ZHENG ; Boteng YAN ; Yuanyuan NONG ; Yu YE ; Shengzhu HUANG ; Yu LONG ; Jianmin LI ; Ganqin WANG ; Pei HUANG ; Jinghang JIANG ; Fan WU ; Zengnan MO ; Yonghua JIANG
Annals of Laboratory Medicine 2026;46(2):146-154
Background:
Adrenocortical hormones, particularly 11-oxygenated androgens, are pivotal in female reproductive health and fertility. Standardized detection kits and population-specific reference intervals are lacking in China, hindering related clinical applications.
Methods:
A HPLC-tandem mass spectrometry (HPLC-MS/MS) pipeline was developed, rigorously validated, and applied to simultaneously quantify corticosterone, cortisone, cortisol, 18-OH cortisol, androstenedione (A4), 11β-hydroxyandrostenedione (11-OH A4), dehydroepiandrosterone, and dehydroepiandrosterone sulfate in serum samples from 455 reproductive-aged women (18–45 yrs) in Guangxi, China. Age-dependent concentration trends were analyzed, and reference intervals stratified by age (2.5th to 97.5th percentiles) were established. Correlations with body-composition metrics, ethnicity, and the menstrual cycle were investigated.
Results:
The HPLC-MS/MS method demonstrated high precision (intra- and inter-assay CVs < 15%), accuracy, and sensitivity. All eight hormones exhibited significant age-related declines (P < 0.001 for seven hormones; P = 0.001 for 11-OH A4). Notably, 11-OH A4 levels were significantly lower in the 35–45-yr (3.05 nmol/L) and 25–34-yr (3.09 nmol/L) age groups than in the 18–24-yr (3.57 nmol/L) age group, whereas no significant difference was observed between the 35–45-yr and 25–34-yr age groups. Weak negative correlations were observed between the body mass index and corticosterone and cortisone levels, whereas ethnicity and the menstrual cycle showed no significant associations with hormone levels.
Conclusions
We developed an HPLC-MS/MS-based method for simultaneously quantifying eight adrenocortical hormones, including 11-OH A4, and defined age-specific reference intervals for reproductive-aged Chinese women. These findings advance the clinical utility of adrenocortical hormones in diagnosing and managing reproductive disorders.
4.Comparative analysis of the characteristics of imported malaria cases in Nanning City in 2024 and the same period of the previous year
Shu-lin WEI ; Zhi-qiang QU ; Yuan-yuan LUO ; Yan-cui HUANG ; Shu-qin DIAO ; Xue LI ; Sheng-long YANG ; Xiao-yu HUANG ; Mi-fang LUO
Acta Parasitologica et Medica Entomologica Sinica 2026;33(2):81-84
Objective To investigate the epidemiological characteristics of malaria and provide a basis for developing improved prevention and control measures. Methods Data were obtained from the Chinese Disease Prevention and Control Information System. Malaria surveillance data for Nanning City from January 1,2023, to December 31,2024, were exported from the Infectious Disease Reporting Information Management Subsystem. The characteristics of the two groups of malaria cases were compared. Results A total of 103 imported malaria cases were reported in Nanning City in 2024, representing a 38.32% decrease compared with the same period of the previous year. No statistically significant difference were observed between cases reported in 2023 and 2024 in terms of average age, gender ratio, proportion of parasite species, and monthly reporting distribution;however, statistically significant differences were found in the proportion of reporting areas and current residence areas(χ2= 13.572 and 10.355, respectively; P = 0.001 and 0.035, respectively). The proportion of cases reported in Shanglin County and the proportion of cases residing in Shanglin County were both lower than those during the same period of the previous year. Conclusions The high aggregation of imported malaria cases in Nanning City has decreased. Medical institutions in areas other than Shanglin County should strengthen their vigilance against malaria.
5.Mechanism of active ingredient compatibility of Dimocarpus longan Lour. leaves in improving glucose and lipid metabolism disorders in type 2 diabetic mellitus rats
Yanli LIANG ; Shijia AN ; Fengsheng LI ; Jiani MAI ; Anqi HUO ; Jiali WEI ; Zejuan ZHANG ; Shuyan QIN ; Wenqing HUANG ; Jie LIANG
China Pharmacy 2026;37(13):1697-1703
OBJECTIVE To explore the mechanism of the active ingredient compatibility(quercetin, quercitrin and kaempferol at a mass ratio of 2∶9∶3)of Dimocarpus longan Lour. leaves(abbreviated as CDL) on ameliorating glucose and lipid metabolism disorders in type 2 diabetes mellitus (T2DM) rats. METHODS SD rats were randomly divided into blank control group, model group, metformin hydrochloride group (100 mg/kg), and CDL high-, medium- and low-dose groups (280, 140, 75 mg/kg), with 10 rats in each group. Rats in the blank control group were fed with standard chow, while rats in the other groups were given high-sugar and high-fat diet combined with intraperitoneal injection of streptozotocin to establish the T2DM rat model. After successful modeling, rats in each administration group were given corresponding drug solution, and rats in the blank control group and model group were intragastrically administered with equal volume of pure water, once a day, for consecutive 4 weeks. Fasting blood glucose (FBG) was detected at fixed time every week. The curves of oral glucose tolerance test (OGTT) and intraperitoneal insulin tolerance test (IPITT) were plotted, and the area under curve (AUC) was calculated. The pancreatic islet function indexes [fasting insulin (FINS), homeostasis model assessment of insulin resistance (HOMA-IR), insulin sensitivity index (ISI)],blood lipid indexes [total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C)] and hepatic glycogen content were determined. The pathological morphological changes of liver and pancreatic tissues were observed. The protein and mRNA expression levels of molecules related to phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway in liver tissues were detected. RESULTS Compared with the blank control group, the FBG, AUC of IPITT curve, AUC of OGTT curve, HOMA-IR, the levels of FINS, TC, TG and LDL-C, as well as the protein and mRNA expression of phosphatase and tensin homolog, forkhead box protein O1 and glycogen synthase kinase-3β in liver tissues were significantly increased in the model group ( P <0.05). ISI, the levels of HDL-C and hepatic glycogen content, along with the protein and mRNA expression of PI3K, insulin receptor substrate-1, Akt and protein expression of phosphorylated Akt in liver tissues were markedly decreased ( P <0.05). In model group rats, the arrangement of hepatocytes was irregular, the overall structure of pancreatic lobules was disordered, and a large number of inflammatory cell infiltration was observed. Compared with the model group, most of the above quantitative indexes were significantly reversed in the CDL high-dose group ( P <0.05), and the pathological lesions of liver and pancreas were obviously alleviated. CONCLUSIONS CDL can regulate glucose and lipid metabolism disorders, elevate insulin sensitivity and relieve insulin resistance in T2DM rats. Its mechanism may be related to the activation of the PI3K/Akt signaling pathway.
6.Correlation and lag effect between meteorological factors and scarlet fever incidence based on distributed lag nonlinear model
Di QIN ; Li ZHANG ; Xiaokan WEI ; Xiugang GUAN ; Yanhui CHU
Journal of Public Health and Preventive Medicine 2026;37(4):16-20
Objective To explore the correlation and lag effect between meteorological factors and the incidence of scarlet fever in Xicheng District, Beijing, and to provide a theoretical basis for the surveillance, early warning,and scientific prevention and control of scarlet fever. Methods Based on the daily scarlet fever incidence data and concurrent meteorological data in Xicheng District, Beijing from 2010 to 2019, the distributed lag non-linear model (DLNM) was used to analyze the impact of meteorological factors on the incidence of scarlet fever. Results The risk of scarlet fever was the highest when the daily average temperature was 34.2℃ with a lag of 0 days (RR=1.175, 95% CI:1.006-1.372). The risk was the second highest when the daily average temperature was 2.2℃ with a lag of 12 days (RR=1.123, 95% CI:1.044 -1.209). The cumulative relative risk of scarlet fever was statistically significant when the daily average temperature ranged from 27.2℃ to 34.2℃, with the highest cumulative relative risk at 34.2℃ (RR=1.906, 95%CI:1.215-2.989). When the daily average relative humidity was 19.5% with a lag of 6 days, the risk of scarlet fever incidence was the highest (RR=1.022, 95% CI: 1.005-1.040). The cumulative relative risk was statistically significant when the daily average relative humidity ranged from 24.7% to 40.2%, with the highest cumulative relative risk at 27.3% (RR=1.170, 95% CI: 1.020-1.343). The risk of scarlet fever was the highest when the daily average vapor pressure was 1.2 hPa with a lag of 5 days (RR=1.029, 95%CI:1.008-1.050). The cumulative relative risk of scarlet fever was statistically significant when the daily average vapor pressure was 1.2-7.4 hPa, and the highest cumulative risk was when the daily average vapor pressure was 1.2 hPa (RR=1.362, 95% CI:1.022-1.815). Conclusion There is a nonlinear relationship between meteorological factors and the incidence of scarlet fever in Xicheng District, Beijing, with a certain lag effect. Daily average temperature (27.2-34.2℃), daily average relative humidity (28.6~36.3%) and daily average vapor pressure (1.2-7.4 hPa) increase the risk of scarlet fever. These factors can be used as indicators for the prevention, control, surveillance, and early warning of scarlet fever.
7.Mechanism of active ingredient compatibility of Dimocarpus longan Lour. leaves in improving glucose and lipid metabolism disorders in type 2 diabetic mellitus rats
Yanli LIANG ; Shijia AN ; Fengsheng LI ; Jiani MAI ; Anqi HUO ; Jiali WEI ; Zejuan ZHANG ; Shuyan QIN ; Wenqing HUANG ; Jie LIANG
China Pharmacy 2026;37(13):1697-1703
OBJECTIVE To explore the mechanism of the active ingredient compatibility(quercetin, quercitrin and kaempferol at a mass ratio of 2∶9∶3)of Dimocarpus longan Lour. leaves(abbreviated as CDL) on ameliorating glucose and lipid metabolism disorders in type 2 diabetes mellitus (T2DM) rats. METHODS SD rats were randomly divided into blank control group, model group, metformin hydrochloride group (100 mg/kg), and CDL high-, medium- and low-dose groups (280, 140, 75 mg/kg), with 10 rats in each group. Rats in the blank control group were fed with standard chow, while rats in the other groups were given high-sugar and high-fat diet combined with intraperitoneal injection of streptozotocin to establish the T2DM rat model. After successful modeling, rats in each administration group were given corresponding drug solution, and rats in the blank control group and model group were intragastrically administered with equal volume of pure water, once a day, for consecutive 4 weeks. Fasting blood glucose (FBG) was detected at fixed time every week. The curves of oral glucose tolerance test (OGTT) and intraperitoneal insulin tolerance test (IPITT) were plotted, and the area under curve (AUC) was calculated. The pancreatic islet function indexes [fasting insulin (FINS), homeostasis model assessment of insulin resistance (HOMA-IR), insulin sensitivity index (ISI)],blood lipid indexes [total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C)] and hepatic glycogen content were determined. The pathological morphological changes of liver and pancreatic tissues were observed. The protein and mRNA expression levels of molecules related to phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway in liver tissues were detected. RESULTS Compared with the blank control group, the FBG, AUC of IPITT curve, AUC of OGTT curve, HOMA-IR, the levels of FINS, TC, TG and LDL-C, as well as the protein and mRNA expression of phosphatase and tensin homolog, forkhead box protein O1 and glycogen synthase kinase-3β in liver tissues were significantly increased in the model group ( P <0.05). ISI, the levels of HDL-C and hepatic glycogen content, along with the protein and mRNA expression of PI3K, insulin receptor substrate-1, Akt and protein expression of phosphorylated Akt in liver tissues were markedly decreased ( P <0.05). In model group rats, the arrangement of hepatocytes was irregular, the overall structure of pancreatic lobules was disordered, and a large number of inflammatory cell infiltration was observed. Compared with the model group, most of the above quantitative indexes were significantly reversed in the CDL high-dose group ( P <0.05), and the pathological lesions of liver and pancreas were obviously alleviated. CONCLUSIONS CDL can regulate glucose and lipid metabolism disorders, elevate insulin sensitivity and relieve insulin resistance in T2DM rats. Its mechanism may be related to the activation of the PI3K/Akt signaling pathway.
8.Health risk assessment of heavy metals and metalloids in atmospheric PM2.5 from Inner Mongolia Autonomous Region in 2023
Jiake ZHU ; Shengmei YANG ; Yuhan QIN ; Nana WEI ; Wenqian ZHANG ; Xinrui JIA ; Wenyu ZHANG ; Xuanhao BAI ; Minghui YIN ; Li ZHANG ; Huan LI ; Duoduo WU ; Xuanzhi YUE ; Yaochun FAN
Journal of Environmental and Occupational Medicine 2025;42(10):1201-1208
Background The Inner Mongolia Autonomous Region is a vast area with a wide array of ecological environments, resulting in considerable regional variations in air pollution characteristics. Current research is limited by a scarcity of systematic, region-wide studies and risk assessments. Objective To assess the health risks associated with inhalation exposure to nine heavy metal and metalloid elements in atmospheric fine particulate matter (PM2.5) for the population of the Inner Mongolia Autonomous Region. Methods From the 10th to the 16th of each month throughout 2023, atmospheric PM2.5 samples were collected at designated monitoring sites in 12 leagues (cities) across the Inner Mongolia Autonomous Region to analyze the characteristics and trends in concentration. The health risk assessment model developed by the United States Environmental Protection Agency was employed to evaluate both the non-carcinogenic and carcinogenic risks associated with the heavy metal elements beryllium (Be), cadmium (Cd), chromium (Cr), hydrargyrum (Hg), plumbum (Pb), manganese (Mn), and nickel (Ni) and the metalloid elements stibium (Sb) and arsenic (As). Results In 2023, a total of
9.Prevalence of Schistosoma japonicum infections in wild rodents in key areas during the elimination phase
Chao LÜ ; Xiaojuan XU ; Jiajia LI ; Ting FENG ; Hai ZHU ; Yifeng LI ; Ling XU ; Zhihong FENG ; Huiwen JIANG ; Xiaoqing ZOU ; Wenjun WEI ; Zhiqiang QIN ; Yang HONG ; Shiqing ZHANG ; Jing XU
Chinese Journal of Schistosomiasis Control 2025;37(5):475-481
Objective To investigate the prevalence of Schistosoma japonicum infections in wild rodents in schistosomiasis-endemic areas of China, so as to provide insights into formulation of technical guidelines for monitoring of and the precise control strategy for S. japonicum infections in wild rodents during the elimination phase. Methods Two administrative villages where schistosomiasis was historically highly prevalent were selected each from Dongzhi County, Anhui Province, and Duchang County, Jiangxi Province as study villages. Wild rodents were captured from study villages with baited traps or cages at night in June and September, 2021. The number of rodents captured was recorded, and the rodent species was characterized based on morphologi-cal characteristics. Liver tissues were sampled from captured rodents for macroscopical observation of the presence of egg granu- lomas, and S. japonicum infection was detected simultaneously using liver tissue homogenate microscopy, examinations of mesenteric tissues for parasites, and modified Kato-Katz thick smear technique (Kato-Katz technique). A positive S. japonicum infection was defined as detection of S. japonicum eggs or adult worms by any of these methods. The rate of wild rodent capture and prevalence of S. japonicum infections in wild rodents were compared in different study villages and at different time periods, and the detection of S. japonicum infections in wild rodents was compared by different assays. Results The overall rate of wild ro- dent capture was 8.28% (237/2 861) in Dongzhi County, and the wild rodent capture rates were 9.24% (133/1 439) and 7.31% (104/1 422) in two study villages (χ2 = 3.503, P = 0.061), and were 8.59% (121/1 409) and 7.99% (116/1 452) in June and September, 2021, respectively (χ2 = 0.337, P = 0.561). The overall rate of wild rodent capture was 3.72% (77/2 072) in Duchang County, and the wild rodent capture rates were 6.91% (67/970) and 0.91% (10/1 102) in two study villages (χ2 = 51.901, P < 0.001), and were 4.13% (39/945) and 3.37% (38/1 127) in June and September, 2021, respectively (χ2 = 0.815, P = 0.365). Rattus norvegicus was the predominant rodent species captured in both counties, accounting for 70.04% (166/237) of all captured wild rodents in Dongzhi County and 88.31% (68/77) in Duchang County. No S. japonicum infection was detected in wild rodents captured in Duchang County. Nevertheless, the overall prevalence of S. japonicum infections was 51.05% (121/237) in wild rodents captured in Dongzhi County, with prevalence rates of 50.38% (67/133) and 51.92% (54/104) in two study villages (χ2 = 0.098, P = 0.755), and 54.31% (63/116) and 47.93% (58/121) in September and June, 2021, respectively (χ2 = 0.964, P = 0.326). Of 237 wild rodents captured in Dongzhi County, there were 140 (59.07%) rodents with visible hepatic egg granulomas, 117 (49.47%) tested positive for S. japonicum eggs by liver tissue homogenate microscopy, 34 (14.35%) tested positive for S. japonicum eggs with Kato-Katz technique; however, no adult S. japonicum worms were detected in mesenteric tissues. In addition, hepatic egg granulomas were found in all wild rodents tested positive for S. japonicum eggs with liver tissue homogenate microscopy. Conclusions The rate of wild rodent capture and prevalence of S. japonicum infection in wild rodents vary greatly in schistosomiasis-endemic areas of China, and the prevalence of S. japonicum infection is slightly higher in wild rodents captured in autumn than in summer. Liver tissue is recommended as the preferred sample for surveillance of S. japonicum infection in wild rodents, and a combination of macroscopical observation of hepatic egg granulomas and liver tissue homogenate microscopy may be a standard method for surveillance of S. japonicum infection in wild rodents.
10.Colorimetric Detection of Sodium Dodecyl Benzene Sulfonate Based on Silver Phosphate/Nickel Hydroxystannate with Oxidase-like Activity
Qin HE ; Zhen-Bo YUAN ; Qi ZHANG ; Li-Li DU ; Bao-Jun HUANG ; Wei-Wei HE
Chinese Journal of Analytical Chemistry 2025;53(10):1654-1663
A highly efficient oxidase-mimetic silver phosphate/nickel hydroxystannate(Ag3PO4/NiSn(OH)6)composite was synthesized via a precipitation method using nickel hydroxystannate(NiSn(OH)6)as the support.The abundant hydroxyl groups(—OH)on NiSn(OH)6 not only provided nucleation sites for Ag3PO4 nanoparticles but also improved their dispersion and overall material stability.Based on oxidase-like activity of Ag3PO4/NiSn(OH)6 and inhibitory effect of sodium dodecylbenzenesulfonate(SDBS)on this catalytic activity,a novel colorimetric sensing method for SDBS detection was developed.Under optimized experimental conditions,the method exhibited a linear range of 3.69-42.7 μmol/L,with a detection limit of 0.135 μmol/L(S/N=3).The regression equation was ΔA652=0.01125C(μmol/L)+0.1498,with a correlation coefficient(R2)of 0.992.Practical application in dishwashing liquid analysis achieved satisfactory recoveries of 96.9%-106.4%,demonstrating the method's reliability for real sample detection.


Result Analysis
Print
Save
E-mail