1.Herbal Textual Research on Cynanchi Atrati Radix et Rhizoma in Famous Classical Formulas
Xiaoqi JING ; Minna GUO ; Haihua WANG ; Juan LI ; Fusheng ZHANG ; Zhilai ZHAN
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(4):208-216
This article systematically reviews and verifies the name, origin, production area, quality evaluation, harvesting, processing and other aspects of Cynanchi Atrati Radix et Rhizoma(CARR) by consulting relevant ancient and modern literature, in order to provide a basis for the development and utilization of famous classical formulas containing this herb. Through textual research, Baiwei has been the official name for CARR, though it also bears alternative names such as Chuncao, Popo Zhenxianbao, Longdan Baiwei. The mainstream base is the roots and rhizomes of Cynanchum atratum. Historical records indicate primary producing areas include Shandong, Anhui, Jiangsu, Shaanxi and Shanxi. Since the late Ming dynasty, varieties from Juxian, Yishui and Rizhao in Shandong have been highly regarded as authentic, commonly known as eastern Baiwei. Since modern times, its quality has been summarized as fine, slender, and straight fibrous roots, pale yellow exterior, whiter interior, and dryness with easy breakability are considered superior. The harvesting time before the Song dynasty was on the third day of the third lunar month, but after the Song dynasty, harvesting was possible in both spring and autumn. The initial processing methods of CARR in ancient times included drying in the shade, removing Lu(the little rhizomes which are on tap of roots), and removing mustaches, modern methods involve washing and sun-drying. During the Northern and Southern dynasties, processing methods included steaming. In the Song dynasty, drying and light stir-frying were predominant, while wine washing emerged in the Ming dynasty. Modern practices primarily involve using raw, stir-frying or honey processing. Regarding the medicinal properties of CARR, both ancient and modern texts agree it has a bitter and salty taste and is non-toxic. Records prior to the Qing dynasty predominantly describe its nature as extremely cold, while mainstream herbal texts after the Qing dynasty generally characterize it as cold. Before the Ming dynasty, there were no records of its meridian tropism. It was not until the Qing dynasty that it was recorded in the lung meridian. Modern records mainly refer to the stomach, liver, and kidney meridians. Throughout history, its main functions have been to clear heat, diuresis, nourish Yin, and replenish essence, primarily treating Yin deficiency and fever syndrome. Based on the research results, it is suggested that when developing famous classical formulas containing CARR, the dried roots and rhizomes of C. atratum can be selected as its medicinal source. If there are no specific processing requirements, raw products can be selected as medicine. If the processing requirements are specified, corresponding processed products can be selected as medicine according to the original formula requirements.
2.Analyses of infection characteristics of human respiratory syncytial virus in hospitalized children at a pediatric hospital in Shanghai from 2021 to 2024
Jing WANG ; Weiqin JIANG ; Yuzhe GUO ; Lijiao LIU ; Jian LIU
Shanghai Journal of Preventive Medicine 2026;38(2):97-103
ObjectiveTo analyze the infection characteristics of human respiratory syncytial virus (HRSV) among children hospitalized with acute lower respiratory tract infection (ALRTI) in a specialized pediatric hospital in Shanghai, so as to provide evidence-based support for optimizing the prevention and control strategies and clinical diagnosis and treatment of respiratory tract infections in children in this region. MethodsA retrospective analysis was performed to the clinical and etiological data of 29 260 children hospitalized for ALRTI in Shanghai Children’s Hospital from January 2021 to December 2024. HRSV and 12 other common respiratory pathogens were detected with multiplex polymerase chain reaction (PCR) and capillary electrophoresis. Demographic and clinical data were collected for statistical analyses. A total of2 412 cases with positive HRSV were divided into the severe group and the non-severe group. Clinical characteristics between the two groups were compared using the Mann-Whitney U test and the chi- square (χ2) test. Additionally, the related influencing factors of severe HRSV infection were explored. ResultsThe overall positivity rate of HRSV from 2021 to 2024 was 8.24% (2 412/29 260), with statistically significant differences observed across the four years (χ2=389.42, P<0.001). The highest positivity rate was in 2021 (14.76%), with a high prevalence throughout the year. In 2022, when non-pharmaceutical interventions (NPIs) were implemented, the HRSV positivity rate was the lowest (4.93%), with a winter-dominant epidemic pattern. In 2023, after the NPIs were lifted, the HRSV positivity rate showed a slight rebound (8.14%), presenting a double-peak pattern. In 2024, the HRSV positivity rate slightly decreased compared to that in 2023 (6.29%), exhibiting a winter and spring-dominant epidemic pattern. Among the hospitalized children with ALRTI, the HRSV positivity rate in males (8.85%) was higher than that in females (7.51%), and the difference was statistically significant (χ2=17.33, P<0.001). Age distribution showed that 82.26% (1 984/2 412) of HRSV infections occurred in children aged 3 years old and below. Besides, as age increased, the infection rate of HRSV showed a gradually decreasing trend (P<0.001). Among the 2 412 children with HRSV infection, the proportion of severe cases was 22.31% (538/2 412), while the non-severe cases accounted for 77.69% (1 874/2 412). Compared with non-severe cases, severe cases were more frequently presented with high fever, longer duration of wheezing, as well as higher rates of underlying diseases or co-infection with Mycoplasma pneumoniae (P<0.001). ConclusionThe prevalence intensity of HRSV varied yearly from 2021 to 2024. After the removal of NPIs in 2023, a slight rebound with a double-peak epidemic pattern was observed. HRSV remained a common pathogen in children hospitalized for ARLTI, and children aged 3 years old and below constituted the highest proportion for infection. Compared with non-severe cases, those with severe HRSV infections were more prone to presenting with high fever and a longer duration of wheezing. Children with positive HRSV who had underlying diseases or co-infection with Mycoplasma pneumonia were more likely to develop severe conditions.
3.Clinical management of patients with hepatitis D
Xu WU ; Jing DOU ; Feng GUO ; HUXIBAIHETI ; Xiaozhong WANG
Journal of Clinical Hepatology 2026;42(2):272-277
Hepatitis D virus (HDV), as a defective virus, relies on the envelope protein of hepatitis B virus (HBV) to complete replication and transmission. Chronic hepatitis B (CHB) patients comorbid with HDV infection may experience significant acceleration of liver disease progression and a significantly higher risk of serious complications such as liver cirrhosis and hepatocellular carcinoma (HCC) compared with the patients with CHB alone, which poses a serious threat to the life and health of patients. At present, the coverage rate of HDV screening needs to be improved, and some patients with HBV/HDV co-infection have not been found in time. Therefore, strengthening the understanding of HDV among clinicians, expanding the scope of HDV screening, identifying patients with infection in a timely manner, and performing standardized antiviral therapy and long-term follow-up management are of great significance for improving the prognosis of patients, reducing disease burden, improving the quality of life of patients, and achieving the global goal of “eliminating viral hepatitis as a public health threat by 2030”.
4.Traditional Chinese Medicine Treats Esophageal Cancer via PI3K/Akt Signaling Pathway: A Review
Wei GUO ; Chen PENG ; Yikun WANG ; Zixuan YU ; Jintao LIU ; Jing DING ; Yijing LI ; Hongxin SUN
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(5):302-311
Esophageal cancer (EC) is a highly prevalent malignant tumor in China. The phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway, as one of the key oncogenic pathways, can promote the cell cycle progression, proliferation, migration, and invasion, induce chemoresistance, and inhibit apoptosis and autophagy of EC cells. Traditional Chinese medicine (TCM), with the advantages of targeting multiple points with multiple components to delay cancer progression, can target the PI3K/Akt signaling pathway for EC treatment. This article preliminarily discusses the molecular mechanism and role of the PI3K/Akt signaling pathway in EC and elaborates on the specific targets and efficacy of TCM in treating EC through intervention in the PI3K/Akt signaling pathway in the past five years. TCM materials and extracts inhibiting the PI3K/Akt signaling pathway in EC include Borneolum, spore powder of Ganoderma lucidum without spore coat, extract of Celastrus orbiculatus, root extract of Taraxacum, and Bruceae Fructus oil emulsion. TCM active ingredients exerting the effect include flavonoids, terpenoids, saponins, phenols, polysaccharides, alkaloids, and other compounds. TCM compound prescriptions with such effect include Qige San, Huqi San, Xuanfu Daizhetang, Tongyoutang and its decomposed prescriptions, Liujunzi Tang, and Xishenzhi Formula. In addition, TCM injections such as Compound Kushen Injection and Kang'ai injection also inhibit the PI3K/Akt signaling pathway in EC. This paper summarizes the role of the PI3K/Akt signaling pathway in EC and the TCM interventions, aiming to provide reference for the research and clinical application of new drugs for EC.
5.Mechanism of Danggui Shaoyaosan in Improving Glomerulosclerosis in db/db Mice via SIRT1/HIF-1α/VLDLr Signaling Pathway
Ruijia LI ; Zixuan WANG ; Shilong GUO ; Jing LI ; Qianqian ZHANG ; Wen DONG ; Dengzhou GUO
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(6):11-18
ObjectiveTo investigate the potential mechanism of Danggui Shaoyaosan (DSS) in ameliorating renal injury in db/db mice. MethodsThirty 8-week-old specific pathogen-free (SPF)-grade male db/db mice and six db/m mice were acclimated for one week. Urinary microalbumin and blood glucose levels were measured weekly in both db/db and db/m mice. Successful modeling was determined by significantly higher microalbuminuria in db/db mice compared to db/m mice and a fasting blood glucose ≥16.7 mmol·L-1. The 30 db/db mice were randomly divided into five groups: the model group, the irbesartan (IBN) group, and three DSS dose groups (low-, medium-, and high-dose DSS groups, administered at 16.77, 33.54, 67.08 g·kg-1·d-1, respectively). Additionally, the six db/m mice served as the normal control group. The IBN group received irbesartan at 0.025 g·kg-1·d-1 by gavage, while the three DSS groups received DSS at 16.77, 33.54, and 67.08 g·kg-1·d-1 by gavage, respectively. The normal and model groups were administered with an equivalent volume of normal saline by gavage. All interventions lasted for 8 consecutive weeks. After intervention, serum creatinine (SCr), blood urea nitrogen (BUN), urinary total protein (UTP), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) were measured to evaluate the therapeutic efficacy of the treatments. Renal histopathological changes were observed with hematoxylin-eosin (HE) staining. Western blot was used to detect the protein expression of silencing information regulator 1 (SIRT1), hypoxia-inducible factor-1α (HIF-1α), very low-density lipoprotein receptor (VLDLr), and cluster of differentiation 31 (CD31). Real-time fluorescence quantitative polymerase chain reaction (Real-time PCR) was used to detect the mRNA levels of HIF-1α and VLDLr. Immunohistochemistry was used to observe the expression and distribution of HIF-1α and Caspase-3. ResultsCompared to the normal group, the model group showed significantly increased SCr, BUN, UTP, TG, and LDL-C. HE staining revealed glomerulosclerosis, mesangial matrix hyperplasia, capillary loop distortion and thickening, with extensive inflammatory cell infiltration. Protein expression of SIRT1 and CD31 significantly decreased (P<0.05), while HIF-1α and VLDLr protein and mRNA levels increased (P<0.05). Immunohistochemistry showed increased expression of HIF-1α and Caspase-3 (P<0.05), indicating hypoxia and apoptosis in renal cells. In all treatment groups, SCr, BUN, TG, and LDL-C were significantly reduced compared to the model group (P<0.05), and UTP was significantly improved in the medium-dose DSS group (P<0.05). Renal tissue structure and morphology were improved, inflammatory cells were reduced, and no vascular hyaline degeneration was observed. SIRT1 and CD31 protein expression was elevated to varying degrees compared to the model group (P<0.05), while HIF-1α and VLDLr protein and mRNA levels decreased (P<0.05). Immunohistochemistry showed reduced expression of HIF-1α and Caspase-3 in all treatment groups (P<0.05), with the most significant improvement observed in the IBN group and medium-dose DSS group (P<0.05). ConclusionDSS can effectively ameliorate glomerulosclerosis and lipid deposition in db/db mice, and its mechanism may involve the SIRT1/HIF-1α/VLDLr signaling pathway.
6.Protective Effect and Potential Mechanism of Danggui Shaoyaosan on Diabetic Kidney Disease in db/db Mice Based on Endoplasmic Reticulum Stress in Glomerular Endothelial Cells
Ruijia LI ; Zixuan WANG ; Shilong GUO ; Sen YANG ; Jing LI ; Qianqian ZHANG ; Wen DONG ; Dengzhou GUO
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(6):28-35
ObjectiveTo investigate the therapeutic efficacy of Danggui Shaoyaosan (DSS) on renal injury in db/db mice and its impact on endoplasmic reticulum stress (ERS) in renal tissues. MethodsThirty 8-week-old male db/db mice and six db/m mice were acclimated for one week, after which urinary microalbumin and blood glucose levels were monitored to establish a diabetic kidney disease (DKD) model. The model mice were randomly divided into a model group, an irbesartan group, and three DSS treatment groups with different doses (16.77, 33.54, and 67.08 g·kg-1·d-1). A normal group was set as control. Each group was intragastrically administered with the corresponding drugs or saline for 8 weeks. After the intervention, general conditions were observed. Serum cystatin C (Cys-C), 24-hour urinary total protein (24 h-UTP), 24-hour urinary microalbumin (24 h-UMA), urinary creatinine (Ucr), and urea nitrogen (UUN) were measured. Transmission electron microscopy (TEM) was used to observe glomerular basement membrane (GBM) and ultrastructural changes of the endoplasmic reticulum (ER) in glomerular endothelial cells. Western blot, real-time fluorescence quantitative polymerase chain reaction (Real-time PCR), and immunohistochemistry were used to analyze renal tissue structure and the expression of GRP78, CHOP, and related markers. ResultsCompared with the normal group, the mice in the model group showed curled posture, sluggish response, poor fur condition, increased levels of Cys-C, 24 h-UTP, 24 h-UMA, and UUN (P<0.05), while Ucr decreased (P<0.05). The GBM was significantly thickened, with podocyte and foot process fusion. The protein expressions of GRP78, CHOP, and ATF6 were significantly upregulated (P<0.05), the mRNA levels of GRP78 and CHOP increased (P<0.05), and immunohistochemistry showed an enhanced GRP78 signal (P<0.05). After treatment, the mice exhibited improved behavior, normalized GBM and podocyte structure, improved ER morphology and markedly better biochemical indicators. Western blot, Real-time PCR, and immunohistochemistry indicated that the ERS-related markers were downregulated in the DSS treatment groups (P<0.05), suggesting alleviated ERS and improved renal function. ConclusionDSS can effectively ameliorate renal pathological damage in db/db mice, possibly by regulating ERS in glomerular endothelial cells, although the underlying signaling mechanisms require further investigation.
7.Expert consensus on the application of artificial intelligence in lung cancer screening, diagnosis, and treatment (2026 edition)
Wenzhao ZHONG ; Haibo WANG ; Yi HU ; Hao ZHANG ; Jigang DAI ; Junqiang FAN ; Guibin QIAO ; Fan YANG ; Jian HU ; Fengwei TAN ; Xuening YANG ; Qiang PU ; Zihao CHEN ; Hongxia TIAN ; Lunxu LIU ; Hecheng LI ; Xiaolong YAN ; Zongyang YU ; Zhenbin QIU ; Yihua SUN ; Jing HU ; Yuhang SHI ; Zhifei GUO ; Peng ZHANG ; Kezhong CHEN ; Shugeng GAO ; Yilong WU
Chinese Journal of Clinical Thoracic and Cardiovascular Surgery 2026;33(06):848-856
With the continuous deepening of the concept of precision diagnosis and treatment for lung cancer, how to achieve higher efficiency and accuracy in the screening, diagnosis, and treatment pathways in clinical practice has become an important issue that urgently needs to be overcome. The current clinical difficulty lies in the fact that despite continuous advancements in imaging and molecular diagnostic technologies, there are still limitations in manual efficiency and subjective experience when it comes to massive data analysis and multi-scale feature extraction. Artificial intelligence (AI), especially algorithm systems based on deep learning, is an innovative technology capable of deeply empowering medical big data. This method utilizes algorithms such as convolutional neural networks, combined with radiomics, pathomics, and multi-modal data fusion analysis, demonstrating immense potential in early precise detection and benign-malignant differentiation of pulmonary nodules, digital pathological subtype recognition and non-invasive prediction of driver genes, precise 3D surgical planning and automatic delineation of radiotherapy target volumes, as well as dynamic risk warning during follow-up. This innovative technology provides a brand-new solution for realizing intelligent and individualized lung cancer diagnosis and treatment models. This consensus, based on the latest evidence from evidence-based medicine and combined with the development trends in the AI field and real-world clinical needs, was ultimately formed by gathering the consensus opinions of multidisciplinary experts in radiology, pathology, thoracic surgery, and other fields. The main content covers the application specifications of AI in the three core scenarios of lung cancer screening, diagnosis, and treatment, the technical standards for data collection and algorithm validation, as well as the ethical and regulatory challenges faced at the current stage. It aims to clarify the applicable boundaries of AI as a clinical auxiliary decision support tool, providing scientific guidance and standardized exploration directions for peers currently engaged in or planning to carry out AI-assisted clinical diagnosis, treatment, and translation of lung cancer.
8.Experience of pedicled tunica vaginalis grafts in the treatment of 90 cases of longsegment anterior urethral stricture >2cm caused by male genital lichen sclerosus
Jing LIU ; Li'e GUO ; Zhongzhong SUN ; Wanglong WANG
Journal of Modern Urology 2026;31(2):147-152
Objective To summarize 20 years' clinical experience of urethroplasty with pedicled tunica vaginalis grafts in the treatment of long-segment anterior urethral stricture (>2 cm) caused by male genital lichen sclerosus (GLSc). Methods A retrospective study was conducted on the clinical data of 90 patients undergoing urethroplasty with pedicled tunica vaginalis grafts in our hospital. Patients were divided into three groups according to the length of stricture: 4-7 cm (n=25), >7-10 cm (n=44), and>10 cm (n=21). The surgical conditions, changes in preoperative and postoperative maximum urinary flow rate (Qmax), and improvements in the international index of erectile function (IIEF-5) scores were compared among the three groups. Results During the follow-up of 6-48 (average 22.0±2.7) months, 88 patients exhibited unimpeded urination, with a success rate of 97.8%. Retrograde urethrography showed the urethral lumen was well-dilated, the penis was not deformed or strictured, and the sexual intercourse was normal. The Qmax of the three groups was significantly improved 2, 6 and 12 months postoperatively (P<0.01), but with no statistically significant differences among the three groups (P>0.05). Similarly, the IIEF-5 scores showed no statistically significant differences among or within the groups (P>0.05). No serious complications occurred after operation. Urethral stricture occurred in 2 cases after operation, one of which had smooth urination after holmium laser urethrotomy, and the other achieved urination after anterior urethral incision. Conclusion Urethroplasty with pedicled tunica vaginalis grafts is suitable for the treatment of long-segment anterior urethral stricture caused by GLSc. It has the advantages of high surgical success rate, convenient graft harvesting, simple operation, few trauma and few complications. This surgical approach is recommended for primary hospitals.
9.Application value of fibrosis-4 index and liver transient elastography in liver fibrosis risk stratification for metabolic associated fatty liver disease in community health institutions
Haiqing GUO ; Yaning LI ; Xiaohui LIU ; Jing ZHANG ; Yumin WANG ; Li CAO ; Lixia QIU
Journal of Clinical Hepatology 2026;42(6):1294-1300
ObjectiveTo perform metabolic associated fatty liver disease (MAFLD) screening among individuals attending community health institutions, to identify the patients at a low, moderate or high risk of advanced liver fibrosis based on fibrosis-4 index (FIB-4) and liver stiffness measurement (LSM) measured by liver transient elastography, and to implement stratified management. MethodsA cross-sectional study was conducted among 630 individuals attending Beijing Baizhifang Community Health Service Center from January to July 2024, and they were divided into MAFLD group and non-MAFLD group. According to body mass index (BMI), the MAFLD group was further divided into lean MAFLD group (BMI<23 kg/m2) and non-lean MAFLD group (BMI≥23 kg/m2). The above groups were compared in terms of demographic features, laboratory markers, hepatic steatosis, and LSM. Fibrosis risk stratification was performed for MAFLD patients based on FIB-4 and LSM, and a closed-loop management system involving referral to tertiary hospitals and follow-up at community health institutions was implemented. The Mann-Whitney U test was used for comparison of non-normally distributed continuous data between two groups, and the chi-square test or the Fisher’s exact test was used for comparison of categorical data between groups. ResultsThere were 445 individuals (70.6%) in the MAFLD group and 185 individuals (29.4%) in the non-MAFLD group. Compared with the non-MAFLD group, the MAFLD group had a significantly lower proportion of male individuals (χ2=4.299, P<0.05), a significant reduction in the level of high-density lipoprotein cholesterol (Z=3.484, P<0.05), and significant increases in body weight (Z=-7.366, P<0.05), BMI (Z=-9.740, P<0.05), waist circumference (Z=-6.397, P<0.05), hip circumference (Z=-6.935, P<0.05), alanine aminotransferase (ALT) (Z=-2.765, P<0.05), fasting blood glucose (Z=-3.646, P<0.05), triglyceride (TG) (Z=-6.569, P<0.05), total cholesterol (Z=-2.033, P<0.05), low-density lipoprotein cholesterol (Z=-2.935, P<0.05), controlled attenuation parameter (CAP) (Z=-19.784, P<0.05), and LSM (Z=-5.703, P<0.05). Within the MAFLD group, there were 124 individuals (27.9%) in the lean MAFLD group and 321 individuals (72.1%) in the non-lean MAFLD group. Compared with the non-lean MAFLD group, the lean MAFLD group had significantly lower body weight (Z=-12.414, P<0.05), BMI (Z=-16.363, P<0.05), waist circumference (Z=-7.733, P<0.05), hip circumference (Z=-8.595, P<0.05), ALT (Z=-2.835, P<0.05), aspartate aminotransferase (Z=-1.972, P<0.05), TG (Z=-2.407, P<0.05), CAP (Z=-4.429, P<0.05), degree of steatosis (χ2=16.588, P<0.05), and LSM (Z=-3.908, P<0.05). Based on the results of FIB-4 and LSM, 76 patients at a moderate or high risk of liver fibrosis should be referred to a higher-level hospital for further management. ConclusionThe detection rate of MAFLD reaches 70.6% among the individuals attending community health institutions, among whom 76 (17.1%) should be referred to a higher-level hospital. Establishing a liver fibrosis risk stratification and management system based on FIB-4 and LSM among MAFLD individuals in communities provides a practical pathway for chronic disease management and referral system construction in community health institutions.
10.Integrated effects of climate, land use, and their interactive driving mechanisms on the spatiotemporal dynamics of Oncomelania hupensis density: a case study of Yunnan Province
Jiangling XIANG ; Suying GUO ; Qiang WANG ; Lijuan ZHANG ; Jiayu SUN ; Yi DONG ; Jing XU
Chinese Journal of Schistosomiasis Control 2026;38(3):260-267
Objective To examine the impact of climate, land use and their interaction effect on the population density of Oncomelania hupensis. Methods O. hupensis snail surveillance data in Yunnan Province from 2013 to 2022 were obtained from the National Information System for Parasitic Diseases Prevention and Control of Chinese Information System for Disease Control and Prevention, and the density of living snails was calculated in each county-level administrative district. Climate data were obtained from the China Meteorological Forcing Dataset version 2.0, and land use data were captured from the China Land Cover Dataset. The raster climate data and land use data were clipped to the administrative border of Yunnan Province in the R package version 4.5, and the climate data were resampled to a spatial resolution of 30 m × 30 m consistent with the land use data using bilinear interpolation. Annual meteorological indicators were extracted from each county-level schistosomiasis surveillance administrative area in Yunnan Province from 2013 to 2022, including average temperature, maximum temperature, minimum temperature, temperature difference, average precipitation rate, maximum precipitation rate, minimum precipitation rate, downward shortwave radiation flux, downward longwave radiation flux, air pressure, wind speed, specific humidity and relative humidity. Annual land use structure and landscape pattern index in each county-level schistosomiasis surveillance administrative area in Yunnan Province from 2013 to 2022 were extracted and calculated, including the proportion of areas occupied by each type of land use, patch density, largest patch index, landscape separation index, landscape fragmentation index, landscape segmentation index, contagion index, patch cohesion index, edge density, and shape index. Land use entropy index was introduced to represent the degree of habitat fragmentation and ecological niche breadth. The density of living snails and environmental factors were subjected to rank correlation analysis, and variables with no statistically significant correlation (P>0.1) were excluded. Then, a correlation coefficient matrix was constructed, and |rs| of 0.85 and greater was defined as the threshold of high collinearity. For highly correlated variables in each group, indicators with a more biological explanatory power or a better statistical efficiency were retained. A generalized additive model (GAM) was constructed with O. hupensis snail density as a response variable and screened environmental variables as independent variables, and the model performance was evaluated using the variance explained. Results The area occupied by O. hupensis snail habitats was 1 056 to 1 680 hm2 in Yunnan Province from 2013 to 2022, appearing an overall tendency towards a decline; however, the density of living snails appeared a tendency towards a slight rise. Based on the correlation coefficient matrix, 14 core explanatory variables were retained, including farmland, water bodies, bare land, impervious surface, landscape separation index, landscape fragmentation index, edge density, shape index, land use entropy index, downward longwave radiation flux, downward shortwave radiation flux, maximum temperature, minimum precipitation rate and specific humidity. Two types of GAM were constructed, including the main-effects model without interaction terms and the interaction model with interaction terms. The corrected Akaike information criterion (AICc) of the optimal main-effects model was −285.223, and the core variables included bare land, impervious surface, landscape separation index, edge density, shape index, land use entropy index and downward shortwave radiation flux. Following introduction of second-order interaction terms, the AICc value of the optimal interaction model was −345.526, and the significant interaction combinations included: farmland × impervious surface, farmland × landscape separation index, farmland × shape index, farmland × land use entropy index, impervious surface × landscape separation index, impervious surface × edge density, and shape index × downward shortwave radiation flux. The proportion of the main-effects model explaining the variation of O. hupensis snail density was 39.8%, and the explanatory power of GAM increased to 79.0% following introduction of interaction terms. Conclusion Landscape separation index, edge density, shape index and other landscape pattern indicators pose significant impacts on the intensity and direction of changes in O. hupensis snail density in Yunnan Province.

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