1.Atelocollagen Improves Bone-to-Tendon Interface Healing in a Rabbit Model of Chronic Rotator Cuff Tear Compared with Polydeoxyribonucleotide
Jian HAN ; Zhan-Feng ZHANG ; Shen-Yun FANG ; Yun-Mei CUI ; Sheng Chen HAN
Clinics in Orthopedic Surgery 2026;18(1):167-175
Background:
Surgeons face challenges in selecting cost-effective and biologically active agents for rotator cuff healing, given the numerous commercial products available, such as polydeoxyribonucleotide (PDRN) and atelocollagen (ATC). However, the precise efficacy of PDRN and ATC in rotator cuff healing remains debatable, and there is currently a lack of studies directly comparing the effects of the 2 agents on repaired cuff tendons. Therefore, the purpose of this study was to compare the efficacy of PDRN and ATC on bone-to-tendon interface (BTI) healing using a chronic rotator cuff tear (RCT) model in rabbits.
Methods:
Forty-eight rabbits were randomly divided into 3 groups. To create chronic RCT models, transected tendons were left untreated for 6 weeks, and then were repaired in a transosseous manner with PDRN and ATC injection into the repair site according to group allocation (group A: saline, group B: PDRN, group C: ATC; n = 16 per group). Genetic and immunofluorescence analyses were performed at 4 weeks after surgery. Furthermore, genetic, histologic, and biomechanical analyses were performed at 12 weeks after surgery.
Results:
At 4 weeks after surgery, ATC-injected shoulders showed the highest mRNA expression levels of collagen type I alpha 1 and aggrecan compared to the other 2 groups (p < 0.001 and p = 0.002, respectively). Meanwhile, there was more preliminary fibrocartilaginous matrix formation in the ATC-injected group. At 12 weeks after surgery, ATC-injected shoulders demonstrated better collagen fiber continuity and orientation, denser collagen fibers, a more mature bone-to-tendon junction, and greater fibrocartilage layer formation compared to the other 2 groups (all p < 0.001). Furthermore, ATC-injected shoulders also demonstrated a significantly higher load-to-failure value (40.4 ± 4.5 N/kg) than the remaining groups (group A, 26.7 ± 3.0 N/kg; group B, 32.8 ± 4.2 N/kg; p < 0.001).
Conclusions
ATC demonstrated superior efficacy in promoting BTI healing following surgical repair in a chronic RCT model of rabbits.
2.Mechanisms of Sini San in Regulation of Gut Microbiota Against Depression and Liver Injury in CUMS Rats
Junling LI ; Yan ZHANG ; Lei WANG ; Fang QI ; Zhenzhen CHEN ; Tianxing CHEN ; Yuhang LIU ; Xueying WANG ; Xianwen TANG ; Yubo LI
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(3):33-40
ObjectiveTo explore the efficacy and mechanisms of Sini San in the treatment of depression and liver injury based on gut microbiota. MethodsThirty-two male Sprague-Dawley (SD) rats were randomly divided into a normal group, model group (M), Sini San group (MS, 2.5 g·kg-1), and fluoxetine group (MF, 2 mg·kg-1). Except for the normal group, rats in the other three groups were subjected to chronic unpredictable mild stress (CUMS). After 8 weeks, the open-field test and sucrose preference test were conducted. Enzyme-linked immunosorbent assay (ELISA) was used to detect serum corticosterone (CORT), adrenocorticotropic hormone (ACTH), corticotropin-releasing factor (CRF), lipopolysaccharide (LPS), Zonulin, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), γ-aminobutyric acid (GABA) levels in the hippocampus and prefrontal cortex, and brain-derived neurotrophic factor (BDNF) levels in the hippocampus. Real-time quantitative polymerase chain reaction (Real-time PCR) was used to detect hippocampal BDNF mRNA expression. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were measured using the ultraviolet lactate dehydrogenase method. The ultrastructure of the intestinal epithelium was observed by electron microscopy, and gut microbiota in rat feces were analyzed using 16S rDNA high-throughput sequencing. ResultsCompared with the normal group, the sucrose preference of rats in the model group was significantly reduced (P0.01), whereas it was significantly increased in the Sini San group compared with the model group (P0.05). Compared with the normal group, hippocampal GABA protein levels and BDNF mRNA expression in the model group were significantly decreased (P0.05), and compared with the model group, both were significantly increased in the Sini San group (P0.05, P0.01). Compared with the normal group, serum LPS and Zonulin levels in the model group were significantly increased (P0.05, P0.01), and compared with the model group, Zonulin levels in the Sini San group were significantly decreased (P0.05). No obvious changes were observed in the ultrastructure of the jejunal mucosa among groups. Compared with the normal group, widened and blurred tight junctions, sparse and shortened microvilli, and mitochondrial swelling with cristae disruption in epithelial cells were observed in the ileal and colonic mucosa of the model group, which were markedly improved in the Sini San and fluoxetine groups. The results of 16S rDNA high-throughput sequencing showed that Sini San improved CUMS-induced dysbiosis of Bacteroidetes and Proteobacteria. Correlation analysis indicated that Bacteroidetes and Proteobacteria were significantly correlated with depression-related indicators, liver function, and intestinal mucosal permeability. ConclusionSini San exerts antidepressant and hepatoprotective effects by improving Bacteroidetes and Proteobacteria and inhibiting the increase in intestinal mucosal permeability in CUMS rats.
3.Mechanisms of Sini San in Regulation of Gut Microbiota Against Depression and Liver Injury in CUMS Rats
Junling LI ; Yan ZHANG ; Lei WANG ; Fang QI ; Zhenzhen CHEN ; Tianxing CHEN ; Yuhang LIU ; Xueying WANG ; Xianwen TANG ; Yubo LI
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(3):33-40
ObjectiveTo explore the efficacy and mechanisms of Sini San in the treatment of depression and liver injury based on gut microbiota. MethodsThirty-two male Sprague-Dawley (SD) rats were randomly divided into a normal group, model group (M), Sini San group (MS, 2.5 g·kg-1), and fluoxetine group (MF, 2 mg·kg-1). Except for the normal group, rats in the other three groups were subjected to chronic unpredictable mild stress (CUMS). After 8 weeks, the open-field test and sucrose preference test were conducted. Enzyme-linked immunosorbent assay (ELISA) was used to detect serum corticosterone (CORT), adrenocorticotropic hormone (ACTH), corticotropin-releasing factor (CRF), lipopolysaccharide (LPS), Zonulin, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), γ-aminobutyric acid (GABA) levels in the hippocampus and prefrontal cortex, and brain-derived neurotrophic factor (BDNF) levels in the hippocampus. Real-time quantitative polymerase chain reaction (Real-time PCR) was used to detect hippocampal BDNF mRNA expression. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were measured using the ultraviolet lactate dehydrogenase method. The ultrastructure of the intestinal epithelium was observed by electron microscopy, and gut microbiota in rat feces were analyzed using 16S rDNA high-throughput sequencing. ResultsCompared with the normal group, the sucrose preference of rats in the model group was significantly reduced (P<0.01), whereas it was significantly increased in the Sini San group compared with the model group (P<0.05). Compared with the normal group, hippocampal GABA protein levels and BDNF mRNA expression in the model group were significantly decreased (P<0.05), and compared with the model group, both were significantly increased in the Sini San group (P<0.05, P<0.01). Compared with the normal group, serum LPS and Zonulin levels in the model group were significantly increased (P<0.05, P<0.01), and compared with the model group, Zonulin levels in the Sini San group were significantly decreased (P<0.05). No obvious changes were observed in the ultrastructure of the jejunal mucosa among groups. Compared with the normal group, widened and blurred tight junctions, sparse and shortened microvilli, and mitochondrial swelling with cristae disruption in epithelial cells were observed in the ileal and colonic mucosa of the model group, which were markedly improved in the Sini San and fluoxetine groups. The results of 16S rDNA high-throughput sequencing showed that Sini San improved CUMS-induced dysbiosis of Bacteroidetes and Proteobacteria. Correlation analysis indicated that Bacteroidetes and Proteobacteria were significantly correlated with depression-related indicators, liver function, and intestinal mucosal permeability. ConclusionSini San exerts antidepressant and hepatoprotective effects by improving Bacteroidetes and Proteobacteria and inhibiting the increase in intestinal mucosal permeability in CUMS rats.
4.Exploring Mechanism of Anti-atherosclerosis Effect of Huangqi Chifengtang Based on AMPK/PPARα Signaling Pathway and NLRP3 Inflammasome
Yuqin LIANG ; Jie LIU ; Chi ZHANG ; Pingping CHEN ; Fang LU ; Shumin LIU
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(1):131-139
ObjectiveTo explore the improving effect of Huangqi Chifengtang(HCT) on atherosclerosis(AS), and elucidate its mechanism in relation to adenosine monophosphate-activated protein kinase(AMPK)/peroxisome proliferator-activated receptor α(PPARα) signaling pathway and nucleotide-binding oligomerization domain(NOD)-like receptor thermal protein domain associated protein 3(NLRP3) inflammasome. MethodsEight C57BL/6J mice were set as the normal group, and 32 ApoE-/- mice were randomly divided into the model group, the positive drug group(atorvastatin, 5 mg·kg-1·d-1), HCT low- and high-dose groups(1.95, 3.90 g·kg-1·d-1). ApoE-/- mice were fed with high-fat and high-cholesterol feed to establish an AS mouse model. After modeling, they were orally administered corresponding dose of drugs for 28 days, while the normal and model groups received an equal volume of physiological saline via oral gavage. Hematoxylin-eosin(HE) staining was used to observe the pathological status of the aorta and liver in mice, Biochemical testing and enzyme-linked immunosorbent assay(ELISA) were used to detect the levels of total cholesterol(TC), triglycerides(TG), low-density lipoprotein cholesterol(LDL-C), alanine aminotransferase(ALT), aspartate aminotransferase(AST), C-reactive protein(CRP), interleukin(IL)-1β, IL-18 in the serum, as well as superoxide dismutase(SOD), malondialdehyde(MDA), and reduced glutathione(GSH) in the liver. Real-time fluorescence quantitative polymerase chain reaction(Real-time PCR) was used to measure the mRNA expression levels of NLRP3, apoptosis-associated speck-like protein(ASC), cysteinyl aspartate specific proteinase-1(Caspase-1), Toll-like receptor 4(TLR4) in the aorta, and fatty acid synthase(FAS), stearoyl-CoA desaturase 1(SCD1), PPARα, and carnitine palmitoyltransferase 1A(CPT1A) in the liver. Immunohistochemistry was used to determine the protein expressions of NLRP3, Caspase-1, and ASC in the aorta, and Western blot was used to measure the protein expressions of AMPK, p-AMPK, sterol regulatory element binding protein-1c(SREBP-1c), CPT1A, and FAS in the liver. ResultsCompared with the normal group, the model group showed a significant increase in lipid plaque deposition in the aorta and lipid accumulation in the liver, the levels of TC, TG, LDL-C, AST, ALT, IL-1β, IL-18 and CRP in the serum were significantly increased(P<0.01), and the mRNA and protein expressions of aortic TLR4, NLRP3, Caspase-1 and ASC were significantly upregulated(P<0.01). The levels of SOD and GSH in the liver were significantly reduced, while the level of MDA was significantly increased(P<0.01). The mRNA expressions of FAS and SCD1 in the liver were significantly downregulated, while the mRNA expressions of PPARα and CPT1A were significantly upregulated. The protein expressions of p-AMPK/AMPK and CPT1A in the liver were significantly reduced, while the expressions of SREBP-1c and FAS proteins were significantly increased(P<0.01). Compared with the model group, the low- and high-dose HCT groups showed significant improvements in aortic plaques and hepatic lipid deposition. The levels of TC, LDL-C, AST, IL-1β and IL-18 in the serum of the low-dose HCT group, as well as TC, TG, LDL-C, AST, ALT, IL-1β, IL-18 and CRP in the serum of the high-dose HCT group, were significantly reduced(P<0.01). The mRNA expressions of TLR4, NLRP3 and Caspase-1 in the aorta of the low-dose HCT group, as well as TLR4, NLRP3, Caspase-1 and ASC in the aorta of the high-dose HCT group, were significantly downregulated(P<0.01). The protein expressions of Caspase-1 and ASC in the aorta of the low-dose HCT group, as well as NLRP3, Caspase-1 and ASC in the high-dose HCT group, were significantly downregulated(P<0.01). The levels of SOD and GSH in the liver of the low- and high-dose HCT groups were significantly increased, while the level of MDA in the high-dose HCT group was significantly decreased(P<0.05, P<0.01). In the HCT-treated group, the mRNA expressions of FAS and SCD1 in the liver were significantly upregulated, while the mRNA expressions of PPARα and CPT1A were significantly downregulated, the protein expressions of p-AMPK/AMPK and CPT1A in the liver were significantly increased, while the protein expressions of SREBP-1c and FAS were significantly decreased(P<0.05, P<0.01). ConclusionHCT can improve lipid metabolism by activating the AMPK/PPARα pathway and inhibit NLRP3 inflammasome-mediated inflammatory responses, thereby reducing hepatic lipid deposition and AS plaque formation.
5.Pharmacodynamic Substances and Mechanisms of Xinglou Chengqi Tang in Treating Post-stroke Complications: A Review
Yujin ZHANG ; Xiangzhuo LIU ; Zhouyang CHEN ; Zihao SONG ; Xinyi LIU ; Yizhi YAN ; Chaoya LI ; Yingyan FANG ; Shasha YANG ; Xueqin CHENG ; Zhou XIE ; Sijie TAN ; Peng ZENG ; Yue ZHANG
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(1):327-337
Stroke is the leading cause of death and disability among adults in China, and its common complications include digestive system abnormalities, cognitive impairment, depression, stroke-associated pneumonia, and hemiplegia. The combination of traditional Chinese and Western medicine has great potential in treating post-stroke complications. Xinglou Chengqitang (XLCQT) is a representative prescription of alleviating the disease in the upper part by treating the lower part. It has definite therapeutic effect and high safety. Clinically, XLCQT is often used to treat stroke and its complications. However, the quantity and quality of clinical trials of XLCQT in treating post-stroke complications need to be improved. Additionally, since the basic research is weak, the material basis and multi-target mechanism for the efficacy of this prescription are unknown. This article reviews XLCQT in terms of the pharmacodynamic basis, medicinal properties, safety evaluation, and progress in clinical research and mechanisms in treating post-stroke complications. This article summarizes 22 key active ingredients of XLCQT in treating acute stroke complicated with syndrome of phlegm heat and fu-organ excess. Among these key active ingredients, resveratrol, kaempferol, luteolin, chrysoeriol, apigenin, (+)-catechin, and adenosine have good pharmacokinetic properties and high bioavailability. The mechanisms of XLCQT in treating post-stroke complications are complex, including inflammatory response, brain-gut axis, hypothalamic-pituitary-adrenal (HPA) axis, intestinal flora, neurotrophic factors, autophagy, oxidative stress, and free radical damage. This review helps to deeply understand the pharmacodynamic basis and mechanisms of XLCQT in treating post-stroke complications and provides a theoretical basis for the clinical application of XLCQT against post-stroke complications and the development of drugs.
6.Analysis of data from the survey of radiotherapy resources in Gansu Province, China, 2024
Jialong WU ; Yun WANG ; Hanyu ZHANG ; Jie WANG ; Yanjun WANG ; Fang WANG ; Qian WANG ; Ruiying WANG ; Xiangru QU ; Limei NIU ; Qin CHEN
Chinese Journal of Radiological Health 2026;35(1):1-5
Objective To investigate the current distribution of radiotherapy resources in Gansu Province, evaluate the equity of resource allocation, and provide a scientific basis for optimizing regional resource allocation. Methods A questionnaire survey was carried out to assess radiotherapy resources in medical institutions across Gansu Province, China. The equity of radiotherapy resource distribution and associated disparities were assessed using the Gini coefficient, Lorenz curve, and Theil index. Results A total of 23 medical institutions in Gansu Province provided radiotherapy services, comprising 39 radiotherapy devices and 438 professionals, of whom medical physicists accounted for 16.9%. The radiotherapy frequency was 0.47 cases per thousand population. The Gini coefficients for radiotherapy resource distribution ranged from 0.38 to 0.56 by population and from 0.52 to 0.70 by geography. The Theil index for radiotherapy resources ranged from 1.36 to 3.67. Conclusion Radiotherapy resources in Gansu Province were insufficient, and the capacity of radiotherapy service was suboptimal. The equity of radiotherapy resource allocation by geography was worse than that by population. Therefore, it is imperative to address the shortage of radiotherapy resources, strengthen the professional workforce, enhance the capacity radiotherapy service and resource utilization, optimize resource allocation, and promote regional equity in radiotherapy provision in Gansu Province.
7.Relationship between non-suicidal self-injury behaviors, impulsivity, and emotional regulation in adolescents with depressive disorder
Mingfei ZHANG ; Xinyu CHEN ; Fang LIANG ; Zhe CHEN ; Lu QIAN ; Zhijia LI
Sichuan Mental Health 2026;39(1):21-26
BackgroundAdolescents with depressive disorder often engage in non-suicidal self-injury (NSSI) behaviors, which severely impacts their physical and mental health. Impulsivity and emotional regulation are key factors influencing NSSI behaviors. However, research on the mechanisms through which impulsivity and emotional regulation affect NSSI behaviors in adolescent depressive disorder patients with NSSI remains insufficient, limiting the development of effective intervention strategies. ObjectiveTo explore the differences in impulsivity and emotion regulation abilities between adolescent patients with depressive disorder accompanied by and without NSSI behaviors, and to analyze the association between NSSI behaviors and impulsivity and emotion regulation abilities in adolescent patients with depressive disorder accompanied by NSSI behaviors. MethodsA total of 184 adolescents hospitalized in the child and adolescent psychiatry department of Wuxi Mental Health Center from October 2023 to August 2024, who met the diagnostic criteria for depressive disorder according to the Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5), were consecutively enrolled as study subjects. Based on the diagnostic criteria for NSSI in DSM-5, patients were divided into NSSI group (n=108) and non-NSSI group (n=76). The Barratt Impulsiveness Scale-11 (BIS-11), the Emotion Regulation Questionnaire (ERQ), the Adolescent Self-Harm Questionnaire, and the Positive and Negative Suicide Ideation (PANSI) were used for assessment. Spearman correlation analysis was employed to explore the correlation between the scores of the Adolescent Self-Harm Questionnaire and the scores of BIS-11 and ERQ in the NSSI group. Multiple regression analysis was conducted to examine the effects of impulsivity and emotion regulation on NSSI behaviors in the NSSI group. ResultsCompared to the non-NSSI group, the NSSI group showed significantly higher scores in BIS-11 non-planned impulsivity (Z=-4.181, P<0.05), action impulsivity (t=4.944, P<0.05), cognitive impulsivity (Z=-3.392, P<0.05), and total score (t=4.763, P<0.05), and lower scores in the cognitive reappraisal of ERQ (t=-4.094, P<0.05) and total score (Z=-2.299, P<0.05), and higher scores in the expression inhibition of ERQ (Z=-3.019, P<0.05). The correlation analysis results showed that the score of the adolescent self-harm questionnaire in the NSSI group was positively correlated with the behavioral impulsivity factor score in the BIS-11 (r=0.434, P<0.05). Multiple regression analysis indicated that action impulsivity factor was a significant correlate of self-injury behaviors in the NSSI group (B=0.855, P<0.05), explaining 22.30% of the total variance. ConclusionAdolescent patients with depressive disorder accompanied by NSSI behaviors exhibit higher levels of impulsivity and poorer emotional regulation abilities. Action impulsivity may play a significant role in the mechanism of NSSI behaviors. [Funded by Wuxi Municipal Health Commission Research Project (number, Q202320)]
8.Associations between Metabolic Syndrome Indicators and Colon Polyps: A Mendelian Randomization Study
Dongya CHEN ; Hong XU ; Zhaolin ZHANG ; Fang CHEN ; Qingqing LU ; Feng PAN
Endocrinology and Metabolism 2026;41(2):256-266
Background:
While observational studies have suggested a potential link between metabolic syndrome (MetS) and an increased risk of colon polyps, the causal nature of this association remains uncertain. This study used a two-sample Mendelian randomization (MR) approach to evaluate the relationship between MetS and colon polyps.
Methods:
A two-sample MR analysis was performed using data on MetS, its indicators, and colon polyps obtained from publicly available genome-wide association studies in the Integrative Epidemiology Unit (IEU) and MAGIC databases. Outliers were removed using Mendelian Randomization Pleiotropy RESidual Sum and Outlier (MR-PRESSO), followed by MR calculations and false discovery rate (FDR) correction. The primary analysis was conducted with the inverse variance-weighted (IVW) method.
Results:
The IVW results indicated no association between hypertension, hyperlipidemia, or diabetes and the risk of colon polyps. High-density lipoprotein cholesterol (HDL-C) (P=0.005), 2-hour glucose (P=0.004), glycated hemoglobin A1c (P=0.004), and the ratio of omega-6 to omega-3 fatty acids (P<0.001) were negatively associated with colon polyps. Conversely, body mass index (BMI) (P<0.001), body fat percentage (P=0.002), waist-to-hip ratio adjusted for BMI (P=0.001), total cholesterol (TC) (P=0.002), triglycerides (TG) (P<0.001), and both omega-3 (P<0.001) and omega-6 fatty acid levels (P=0.02) were positively associated with colon polyps. The relationships between these metabolic indicators and colon polyps remained significant after FDR correction.
Conclusion
Obesity-related traits, TC, and TG may increase the risk of colon polyps, while HDL-C may have a protective effect.
9.Analysis of Differences in the Intestinal Flora of Rats and Mice after Drinking Chlorinated Water Based on 16S rRNA Sequencing
Xiufeng AI ; Lizong ZHANG ; Mingsun FANG ; Dongying LÜ ; Chu CHEN ; Zhaowei CAI ; Dejun WANG
Laboratory Animal and Comparative Medicine 2026;46(3):437-445
ObjectiveTo evaluate the effects of drinking chlorinated water on the intestinal flora of rats and mice and to explore differences in the intestinal microecological responses of model animals to chlorine stimulation in chlorinated drinking water systems. MethodsSix 8-week-old male SD rats and six 8-week-old male C57BL/6J mice were acclimated for 5 days. Subsequently, the drinking water for both rats and mice was changed from pure water to water containing free chlorine at a concentration of 25.4–32.4 nmol/L. The intervention lasted for 8 weeks, during which all animals were fed the same diet. Fecal samples were collected before the intervention (week 0, as the control group) and on the last day of week 3 and week 8 (as the chlorinated water group), and microbial composition was analyzed by 16S rRNA sequencing, including α diversity (Chao1 and Shannon indices), β diversity [principal component analysis (PCA)], and linear discriminant analysis effect size (LEfSe) analysis. ResultsAfter 3 weeks of intervention, α diversity of the intestinal flora in both rats and mice in the chlorinated water group was significantly lower than that in the control group (P < 0.01). After 8 weeks of intervention, no significant difference in α diversity was observed between rats in the chlorinated water group and those in the control group, whereas α diversity in mice remained significantly lower than that in the control group (P < 0.01). β diversity analysis showed significant alterations in microbial structure in the chlorinated water group. LEfSe analysis indicated that, compared with the control group, the abundances of Bacteroides and Ruminococcus were significantly reduced in the chlorinated water group, and microbial disturbance was more pronounced in mice [linear discriminant analysis (LDA) > 4.0], with a greater decrease in microbial diversity and a larger number of differentially abundant genera. ConclusionConsumption of chlorinated water can alter the diversity and structure of the intestinal flora in both rats and mice, with mice being more sensitive to this exposure. These findings suggest that the potential effects of chlorine on gut microecology should be considered in drinking water management and model selection for animal experiments.
10.Differences in deltamethrin resistance and kdr gene mutation in Culex tritaeniorhynchus population in and outside the Yellow Sea wetland
Xiao-er ZHANG ; Zhi-ming WU ; Ye TIAN ; Qian CUI ; Yu-qian JI ; Huan WANG ; Shu-juan YANG ; Yi-chao ZHAO ; Yu WANG ; Hua-yu YIN ; Yu DING ; Guo-jin YAN ; Min-sen ZHAO ; Shou-gang ZHANG ; Bing-dong SONG ; Hong-na CHEN ; Jian GAO ; Wei-fang YANG ; Yu-fu ZHANG ; Hui LIU ; Hong-liang CHU
Acta Parasitologica et Medica Entomologica Sinica 2026;33(2):101-107
Objective To gain insights into the biological characteristics of different populations of Culex tritaeniorhynchus within and around the Yellow Sea wetland from the perspective of the occurrence of resistance, we investigated the levels of resistance to deltamethrin and kdr gene mutation in the wetland and its peripheral areas. Methods Specimens were collected from Cx. tritaeniorhynchus populations at two monitoring sites in the Rare Bird National Nature Reserve and Tiaozi Ni Wetland Scenic Area, and also from two populations in Yancheng City and the Liuhe District of Nanjing, and the resistance of these mosquitoes to deltamethrin was determined using the CDC biotest bottle method. For each concentration of deltamethrin assessed, a random subset of exposed specimens was selected for amplification of the kdr gene fragment, followed by Sanger sequencing to identify and analyze resistance-associated mutations. Results The LC50 levels of deltamethrin among mosquitoes from the four populations in Luhe, Yancheng, the Rare Bird National Nature Reserve and the Tiaozi Ni Wetland Scenic Area were 2.048 5, 7.798 2, 3.473 3, and 17.695 5 mg/mL, respectively, with corresponding concentrations of deltamethrin ranging from 0.005 to 5.000,0.050 to 50.000,0.050 to 25.000 and 0.050 to 50.000 mg/mL, respectively. Furthermore, the ranges of the KT50 values were 11.76-107.43, 67.05-216.30,29.77-107.43 and 28.40-329.51 min; the 1-h knockdown rates were 34.58%-99.15%, 9.52%-43.80%, 55.09%-73.01%, and 10.09%-68.07%; and the 24-h mortality rates were 12.15%-67.52%,9.52%-79.56%,13.17%-82.21%, and 11.01%-78.99%, respectively. With respect to kdr gene mutation, we assayed a total of 63,70,59, and 57 mosquitoes for the four populations, for which we detected L1014F mutation frequencies of 14.29%, 35.00%, 20.34%, and 31.58%, respectively, with a majority of these mutations being heterozygous for resistance. In addition, five adult mosquitoes were identified has having synonymous mutations at site 1011[i. e. , AAT(asparagine)mutation to AAC(asparagine)]. Conclusions Our findings revealed the clear resistance of Cx. tritaeniorhynchus to deltamethrin in the Yancheng region of the Yellow Sea wetland, and the resistance phenotype and kdr frequency of Cx. tritaeniorhynchus in the wetland environment were comparable to those of Cx. tritaeniorhynchus in the wetland environment, thereby indicating that the resistance of different populations of Cx. tritaeniorhynchus was homogeneous under the pressure of different insecticide selection within and around the wetland. However, the underlying mechanisms need to be further studied.


Result Analysis
Print
Save
E-mail