1.Genomic analysis and multidrug resistance of monophasic Salmonella enterica serovar Typhimurium isolates from Henan
Lingling WU ; Haoyu QI ; Yanfen LI ; Yongli LI ; Jin XU ; Xingguang LIAO ; Xiuli ZHANG ; Zhiwei HAN
Chinese Journal of Laboratory Medicine 2025;48(11):1452-1460
Objective:To analyze the multidrug resistance and genomic characteristics of Monophasic variant of Salmonella enterica serovar Typhimurium (monophasic Salmonella enterica serovar Typhimurium) isolates from clinical patients and food sources in Henan province. Method:A total of 91 monophasic S.Typhimurium strains isolated from clinical and food sources in Henan from 2021 to 2023 were analyzed for antimicrobial sensitivity and underwent whole genome sequencing. Multilocus sequence typing(MLST), multidrug resistance genes and plasmid types were identified using the sequencing data. Phylogenetic tree based on core genome multilocus sequence typing (cgMLST) and single nucleotide polymorphism (SNP) sites was constructed to analyze the genetic evolutionary relationship by comparing with international popular strains in public databases. The Chi-square test was used to compare drug resistance rates. Results:No significant difference was observed in the drug resistance rates between the clinical strains and food strains in Henan [82.19%(60/73) and 11/18, χ2=2.614, P=0.106]. The overall multidrug resistance (MDR) rate was 78.02%(71/91). Most strains were resistant to ampicillin, tetracycline chloramphenicol, β-lactam and sulfonamides. Resistance genes carried by the isolates varied, as well as the drug-resistant phenotypes. MLST showed that 91 strains of S.Typhimurium belonged to ST34 and carried aminoglycoside acetyltransferase gene aac(6′)-Iaa and mobile genetic elements such as plasmids IncQ1 and IncHI2/IncHI2A. The results of cgMLST typing phylogenetic trees showed that food and clinical isolates from the same region in Henan were identified as the same cgST type and clustered in the same branch, which indicated the risk for cross-infection between animal and human. The phylogenetic tree of monophasic S.Typhimurium constructed based on SNP sites showed that the majority of monophasic S.Typhimurium strains in Henan were close to the strains from other provinces in China, other strains were close to the strains from Europe and Southeast Asia, suggesting the possibility of cross regional transmission of the strains. Pork was identified as the main food source. Conclusion:The prevalent ST type of monophasic S.Typhimurium isolated from Henan was ST34, which carried multiple antibiotic resistance genes and widespread drug resistance phenotypes. Most of the monophasic S.Typhimurium isolates in Henan showed a specific phylogenetic lineage with the foreign epidemic strains, indicating the possibility of dissemination of strains between humans and food.
2.Comparison of optical coherence tomography image features between traumatic macular hole and idiopathic macular hole
Tingkun SHI ; Honghe XIA ; Chuang JIN ; Xixuan KE ; Qi ZHANG ; Xulong LIAO ; Yinglin CHENG ; Yuqiang HUANG ; Haoyu CHEN
Chinese Journal of Ocular Fundus Diseases 2025;41(4):289-293
Objective:To comparatively observe optical coherence tomography (OCT) image features between traumatic macular hole (TMH) and idiopathic macular hole (IMH).Methods:A retrospective clinical study. A total of 174 patients (174 eyes) with macular hole (MH) diagnosed at Shantou International Eye Center from December 2008 to May 2024 were included in the study. Among them, there were 75 patients (75 eyes) with TMH and 99 patients (99 eyes) with IMH, and they were divided into the TMH group and the IMH group accordingly. All the affected eyes underwent best corrected visual acuity (BCVA) and OCT examinations. The BCVA was examined using a standard logarithmic visual acuity chart, and was converted to the logarithm of the minimum angle of resolution (logMAR) visual acuity for statistical analysis. The minimum diameter and basal diameter of the MH, as well as the average, nasal, superior, inferior, and temporal center retinal thickness (CRT) around the MH were measured by OCT. The independent-sample t test was used to compare the logMAR BCVA, hole diameter, and CRT at the hole margin between the groups. Results:There were significant differences in age ( t=-15.857) and gender ratio ( χ2=28.154) between the TMH group and the IMH group ( P<0.05), while there was no significant difference in logMAR BCVA ( t=1.962, P>0.05). The minimum diameter of the hole in the TMH group was smaller than that in the IMH group, but the basal diameter was larger, with significant differences ( t=-3.322, 2.570; P<0.05). The thickness of the neuroepithelial layer at the hole margin in the TMH group was thinner than that in the IMH group, with significant differences in the superior ( t=-2.747), inferior ( t=-2.316), and nasal ( t=-2.851) regions ( P<0.05), and no significant difference in the temporal region ( t=-1.586, P>0.05). In the TMH group, the number of eyes with macular cystoid edema (CME), posterior vitreous detachment (PVD), retinal atrophy, subretinal hemorrhage, choroidal laceration, and focal neuroepithelial detachment was 36 (48.00%, 36/75), 4 (5.33%, 4/75), 4 (5.33%, 4/75), 15 (20.00%, 15/75), 8 (10.67%, 8/75), and 19 (25.33%, 19/75) eyes, respectively. In the IMH group, the number of eyes with CME and PVD was 95 (95.96%, 95/99) and 94 (94.95%, 94/99) eyes, respectively. Conclusion:Compared with IMH, TMH has a larger basal diameter, a thinner CRT at the hole margin, a lower incidence of CME and PVD, and a higher incidence of subretinal hemorrhage, focal neuroepithelial detachment, choroidal laceration, and retinal atrophy.
3.Evidence-based guidelines for rehabilitation treatment after internal fixation of thoracolumbar spine fracture in adults (version 2025)
Zhengwei XU ; Liming CHENG ; Qixin CHEN ; Jian DONG ; Shunwu FAN ; Zhong FANG ; Shiqing FENG ; Haoyu FENG ; Haishan GUAN ; Weimin JIANG ; Dianming JIANG ; Yong HAI ; Lijun HE ; Yuan HE ; Bo LI ; Jianjun LI ; Feng LI ; Li LI ; Weishi LI ; Chunde LI ; Qi LIAO ; Baoge LIU ; Xiaoguang LIU ; Yong LIU ; Xuhua LU ; Shibao LU ; Bin LIN ; Wei MEI ; Chao MA ; Renfu QUAN ; Limin RONG ; Jiacan SU ; Honghui SUN ; Yuemin SONG ; Hongxun SANG ; Jun SHU ; Tiansheng SUN ; Jiwei TIAN ; Qiang WANG ; Xinwei WANG ; Zhe WANG ; Zheng WANG ; Liang YAN ; Guoyong YIN ; Jie ZHAO ; Yue ZHU ; Xiaobo ZHANG ; Xuesong ZHANG ; Zhongmin ZHANG ; Rongqiang ZHANG ; Dingjun HAO ; Yanzheng GAO ; Baorong HE
Chinese Journal of Trauma 2025;41(1):19-32
Thoracolumbar spine fracture often leads to severe pain, functional impairments, and neurological deficits, for which open reduction and internal fixation can effectively restore the spinal structural stability. Open decompression and reduction with internal fixation can help relieve spinal cord compression and improve spinal function in cases of concomitant cord injury. Although spinal stability can be restored through surgery, patients often face chronic pain and functional impairments postoperatively. A postoperative rehabilitation program is critical in optimizing therapeutic outcomes, reducing complications, and minimizing the risk of secondary injuries. However, current rehabilitation methods, such as physical therapy, functional training, and pain management, are confronted with problems in clinical practice, including significant variation in efficacy, poor patient adherence, and prolonged rehabilitation period. There is an urgent need for a unified rehabilitation strategy to address these problems. To this end, the Spinal Trauma Group of the Orthopedic Physicians Branch of the Chinese Medical Association and the Spine Health Professional Committee of the Chinese Human Health Technology Promotion Association organized experts from relevant fields to formulate Evidence-based guidelines for rehabilitation treatment after internal fixation of thoracolumbar spine fracture in adults ( version 2025) by integrating evidences from clinical researches and advanced rehabilitation concepts at home and abroad. A total number of 14 recommendations concerning the rehabilitation treatment with multimodal analgesia, psychological intervention, deep vein thrombosis prevention, core muscle and extremity exercise, appropriate use of braces, early weight-bearing, device-aided rehabilitation exercise, neuroregulatory therapy, rehabilitation team were put forward, aiming to standardize the post-operative rehabilitation process following internal fixation, promote the functional recovery, and enhance patients′ quality of life.
4.Clinical guideline for vertebral augmentation of acute symptomatic osteoporotic thoracolumbar compression fractures (version 2025)
Bolong ZHENG ; Wei MEI ; Yanzheng GAO ; Liming CHENG ; Jian CHEN ; Qixin CHEN ; Liang CHEN ; Xigao CHENG ; Jian DONG ; Jin FAN ; Shunwu FAN ; Xiangqian FANG ; Zhong FANG ; Shiqing FENG ; Haoyu FENG ; Haishan GUAN ; Yong HAI ; Baorong HE ; Lijun HE ; Yuan HE ; Hua HUI ; Weimin JIANG ; Junjie JIANG ; Dianming JIANG ; Xuewen KANG ; Hua GUO ; Jianjun LI ; Feng LI ; Li LI ; Weishi LI ; Chunde LI ; Qi LIAO ; Baoge LIU ; Xiaoguang LIU ; Xuhua LU ; Shibao LU ; Bin LIN ; Chao MA ; Xuexiao MA ; Renfu QUAN ; Limin RONG ; Honghui SUN ; Tiansheng SUN ; Yueming SONG ; Hongxun SANG ; Jun SHU ; Jiacan SU ; Jiwei TIAN ; Xinwei WANG ; Zhe WANG ; Zheng WANG ; Zhengwei XU ; Huilin YANG ; Jiancheng YANG ; Liang YAN ; Feng YAN ; Guoyong YIN ; Xuesong ZHANG ; Zhongmin ZHANG ; Jie ZHAO ; Yuhong ZENG ; Yue ZHU ; Rongqiang ZHANG
Chinese Journal of Trauma 2025;41(9):805-818
Acute symptomatic osteoporotic thoracolumbar compression fracture (ASOTLF) can lead to chronic low back pain, kyphosis deformity, pulmonary dysfunction, loss of mobility, and even life-threatening complications. Vertebral augmentation is currently the mainstream treatment method for this condition. In 2019, the Editorial Board of Chinese Journal of Trauma and the Spinal Trauma Group of Orthopedic Surgeons Branch of Chinese Medical Doctor Association collaboratively led the development of Clinical guideline for vertebral augmentation for acute symptomatic osteoporotic thoracolumbar compression fractures. Six years later, with advances in clinical diagnosis and treatment techniques as well as accumulating evidence in related fields, the 2019 guideline requires updating. To this end, the Spinal Trauma Group of Orthopedic Surgeons Branch of Chinese Medical Doctor Association, the Spinal Health Professional Committee of China Human Health Science and Technology Promotion Association, and the Minimally Invasive Orthopedics Professional Committee of Shaanxi Medical Doctor Association have organized experts in the field to develop the Clinical guideline for vertebral augmentation of acute symptomatic osteoporotic thoracolumbar compression fractures ( version 2025) , based on the latest evidence-based medical researches. This guideline incorporates 3 recommendations retained from the 2019 version with updated strength of evidence, along with 12 new recommendations. It provides recommendations from six aspects of diagnosis, pain management, treatment option selection, prevention of postoperative complications, anti-osteoporosis therapy, and postoperative rehabilitation, aiming to provide a reference for standard treatment of vertebral augmentation for ASOTLF in hospitals at all levels.
5.Silencing PTPN2 with nanoparticle-delivered small interfering RNA remodels tumor microenvironment to sensitize immunotherapy in hepatocellular carcinoma.
Fu WANG ; Haoyu YOU ; Huahua LIU ; Zhuoran QI ; Xuan SHI ; Zhiping JIN ; Qingyang ZHONG ; Taotao LIU ; Xizhong SHEN ; Sergii RUDIUK ; Jimin ZHU ; Tao SUN ; Chen JIANG
Acta Pharmaceutica Sinica B 2025;15(6):2915-2929
Protein tyrosine phosphatase nonreceptor type 2 (PTPN2) is a promising target for sensitizing solid tumors to immune checkpoint blockades. However, the highly polar active sites of PTPN2 hinder drug discovery efforts. Leveraging small interfering RNA (siRNA) technology, we developed a novel glutathione-responsive nano-platform HPssPT (HA/PEIss@siPtpn2) to silence PTPN2 and enhance immunotherapy efficacy in hepatocellular carcinoma (HCC). HPssPT showed potent transfection and favorable safety profiles. PTPN2 deficiency induced by HPssPT amplified the interferon γ signaling in HCC cells by increasing the phosphorylation of Janus-activated kinase 1 and signal transducer and activator of transcription 1, resulting in enhanced antigen presentation and T cell activation. The nano-platform was also able to promote the M1-like polarization of macrophages in vitro. The unique tropism of HPssPT towards tumor-associated macrophages, facilitated by hyaluronic acid coating and CD44 receptor targeting, allowed for simultaneous reprogramming of both tumor cells and tumor-associated macrophages, thereby synergistically reshaping tumor microenvironment to an immunostimulatory state. In HCC, colorectal cancer, and melanoma animal models, HPssPT monotherapy provoked robust antitumor immunity, thereby sensitizing tumors to PD-1 blockade, which provided new inspiration for siRNA-based drug discovery and tumor immunotherapy.
6.Pulmonary surfactant-biomimetic membranized coacervate injection for acute respiratory distress syndrome therapy.
Wei CHEN ; Qi XIE ; Zhanhao ZHOU ; Jia KANG ; Yuan GAO ; Haoyu ZHANG ; Samira BATUR ; Chuansheng FU ; Yunyun LI ; Conglian YANG ; Li KONG ; Zhiping ZHANG
Acta Pharmaceutica Sinica B 2025;15(11):5945-5965
Acute respiratory distress syndrome (ARDS) is the leading cause of respiratory failure with high morbidity and mortality. Pulmonary surfactant (PS)-based complementary therapies have exhibited potential for ARDS healing and applied as an adjunctive therapy strategy. Coacervate (Coac) has the characteristics of softness, deformability and excellent molecular enrichment properties, and has attracted extensive attention in the biomedical field. Here PS and coacervate were combined for the potential ARDS treatment. The Coac, fabricated from polyallylamine hydrochloride (PAH) and adenosine triphosphate (ATP) by simple mixing, exhibited soft droplet property and high enrichment for dexamethasone sodium phosphate (DSP). To avoid the fusion effect of membraneless coacervate and endow it with biological functions of PS, liposomes with PS-biomimetic lipid components (PS-lipo) were further introduced to construct PS-biomimetic membranized coacervate (DSP@PS-Coac). The DSP@PS-Coac demonstrated high lung targeting effect and significant penetration efficiency after intravenous injection. Furthermore, PS-lipo replenished the endogenous PS pool and facilitated the distribution of DSP in inflammatory cells in the lung. In the ARDS mouse model, PS-Coac and DSP exerted synergetic anti-inflammatory functions, via reducing the recruitment of inflammatory neutrophils and modulating macrophages into anti-inflammatory phenotype. The overall results confirmed that DSP@PS-Coac may provide a promising delivery option for the treatment of ARDS.
7.Effectiveness analysis of channel-assisted minimally invasive repair technique combined with flexor hallucis longus tendon transfer for Achilles tendon sleeve avulsion.
Lingtong KONG ; Zhonghe WANG ; Haoyu LIU ; Nazhi ZHAN ; Hongzhe QI ; Hua CHEN
Chinese Journal of Reparative and Reconstructive Surgery 2025;39(3):264-270
OBJECTIVE:
To evaluate the effectiveness of the channel-assisted minimally invasive repair (CAMIR) technique combined with flexor hallucis longus (FHL) tendon transfer in the treatment of Achilles tendon sleeve avulsion.
METHODS:
A retrospective analysis was conducted on 17 patients with Achilles tendon sleeve avulsion who underwent CAMIR technique combined with FHL transfer between January 2019 and January 2023. The cohort comprised 13 males and 4 females, aged 32 to 65 years (mean, 49.7 years). Etiologies included sports-related injuries in 15 cases and blunt trauma in 2 cases. The interval from injury to surgery ranged from 4 to 368 days (median, 15 days). All patients exhibited calcification at the Achilles tendon insertion site, with 7 cases complicated by Haglund deformity. Postoperative complications were meticulously monitored, and tendon healing was assessed via MRI. Clinical outcome were evaluated using the visual analogue scale (VAS) score for pain, Tegner activity level rating scale, ankle activity score (AAS), American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, Victorian Institute of Sport Assessment-Achilles (VISA-A) score, and subjective clinical scoring systems preoperatively and at last follow-up.
RESULTS:
The operation time was 50-62 minutes (mean, 56 minutes), and the intraoperative blood loss was 5-50 mL (mean, 19.7 mL). All patients were followed up 12-67 months (mean, 38 months). No postoperative complication, such as Achilles tendon re-rupture, incision infection, deep vein thrombosis, heel raise insufficiency, or sural nerve injury, was observed. At last follow-up, MRI examination confirmed satisfactory tendon healing in all cases. Significant improvements were noted in VAS scores, Tegner activity level rating scale, AAS scores, AOFAS ankle-hindfoot scores, and VISA-A scores compared to preoperative ones ( P<0.05). At last follow-up, the subjective clinical score ranged from 6 to 10 (median, 9).
CONCLUSION
The CAMIR technique combined with FHL tendon transfer is a good treatment for repair of Achilles tendon sleeve avulsion, with good recovery of ankle function and few complications.
Humans
;
Achilles Tendon/diagnostic imaging*
;
Middle Aged
;
Male
;
Female
;
Tendon Transfer/methods*
;
Minimally Invasive Surgical Procedures/methods*
;
Adult
;
Retrospective Studies
;
Aged
;
Treatment Outcome
;
Tendon Injuries/surgery*
8.Evidence-based guidelines for rehabilitation treatment after internal fixation of thoracolumbar spine fracture in adults (version 2025)
Zhengwei XU ; Liming CHENG ; Qixin CHEN ; Jian DONG ; Shunwu FAN ; Zhong FANG ; Shiqing FENG ; Haoyu FENG ; Haishan GUAN ; Weimin JIANG ; Dianming JIANG ; Yong HAI ; Lijun HE ; Yuan HE ; Bo LI ; Jianjun LI ; Feng LI ; Li LI ; Weishi LI ; Chunde LI ; Qi LIAO ; Baoge LIU ; Xiaoguang LIU ; Yong LIU ; Xuhua LU ; Shibao LU ; Bin LIN ; Wei MEI ; Chao MA ; Renfu QUAN ; Limin RONG ; Jiacan SU ; Honghui SUN ; Yuemin SONG ; Hongxun SANG ; Jun SHU ; Tiansheng SUN ; Jiwei TIAN ; Qiang WANG ; Xinwei WANG ; Zhe WANG ; Zheng WANG ; Liang YAN ; Guoyong YIN ; Jie ZHAO ; Yue ZHU ; Xiaobo ZHANG ; Xuesong ZHANG ; Zhongmin ZHANG ; Rongqiang ZHANG ; Dingjun HAO ; Yanzheng GAO ; Baorong HE
Chinese Journal of Trauma 2025;41(1):19-32
Thoracolumbar spine fracture often leads to severe pain, functional impairments, and neurological deficits, for which open reduction and internal fixation can effectively restore the spinal structural stability. Open decompression and reduction with internal fixation can help relieve spinal cord compression and improve spinal function in cases of concomitant cord injury. Although spinal stability can be restored through surgery, patients often face chronic pain and functional impairments postoperatively. A postoperative rehabilitation program is critical in optimizing therapeutic outcomes, reducing complications, and minimizing the risk of secondary injuries. However, current rehabilitation methods, such as physical therapy, functional training, and pain management, are confronted with problems in clinical practice, including significant variation in efficacy, poor patient adherence, and prolonged rehabilitation period. There is an urgent need for a unified rehabilitation strategy to address these problems. To this end, the Spinal Trauma Group of the Orthopedic Physicians Branch of the Chinese Medical Association and the Spine Health Professional Committee of the Chinese Human Health Technology Promotion Association organized experts from relevant fields to formulate Evidence-based guidelines for rehabilitation treatment after internal fixation of thoracolumbar spine fracture in adults ( version 2025) by integrating evidences from clinical researches and advanced rehabilitation concepts at home and abroad. A total number of 14 recommendations concerning the rehabilitation treatment with multimodal analgesia, psychological intervention, deep vein thrombosis prevention, core muscle and extremity exercise, appropriate use of braces, early weight-bearing, device-aided rehabilitation exercise, neuroregulatory therapy, rehabilitation team were put forward, aiming to standardize the post-operative rehabilitation process following internal fixation, promote the functional recovery, and enhance patients′ quality of life.
9.Clinical guideline for vertebral augmentation of acute symptomatic osteoporotic thoracolumbar compression fractures (version 2025)
Bolong ZHENG ; Wei MEI ; Yanzheng GAO ; Liming CHENG ; Jian CHEN ; Qixin CHEN ; Liang CHEN ; Xigao CHENG ; Jian DONG ; Jin FAN ; Shunwu FAN ; Xiangqian FANG ; Zhong FANG ; Shiqing FENG ; Haoyu FENG ; Haishan GUAN ; Yong HAI ; Baorong HE ; Lijun HE ; Yuan HE ; Hua HUI ; Weimin JIANG ; Junjie JIANG ; Dianming JIANG ; Xuewen KANG ; Hua GUO ; Jianjun LI ; Feng LI ; Li LI ; Weishi LI ; Chunde LI ; Qi LIAO ; Baoge LIU ; Xiaoguang LIU ; Xuhua LU ; Shibao LU ; Bin LIN ; Chao MA ; Xuexiao MA ; Renfu QUAN ; Limin RONG ; Honghui SUN ; Tiansheng SUN ; Yueming SONG ; Hongxun SANG ; Jun SHU ; Jiacan SU ; Jiwei TIAN ; Xinwei WANG ; Zhe WANG ; Zheng WANG ; Zhengwei XU ; Huilin YANG ; Jiancheng YANG ; Liang YAN ; Feng YAN ; Guoyong YIN ; Xuesong ZHANG ; Zhongmin ZHANG ; Jie ZHAO ; Yuhong ZENG ; Yue ZHU ; Rongqiang ZHANG
Chinese Journal of Trauma 2025;41(9):805-818
Acute symptomatic osteoporotic thoracolumbar compression fracture (ASOTLF) can lead to chronic low back pain, kyphosis deformity, pulmonary dysfunction, loss of mobility, and even life-threatening complications. Vertebral augmentation is currently the mainstream treatment method for this condition. In 2019, the Editorial Board of Chinese Journal of Trauma and the Spinal Trauma Group of Orthopedic Surgeons Branch of Chinese Medical Doctor Association collaboratively led the development of Clinical guideline for vertebral augmentation for acute symptomatic osteoporotic thoracolumbar compression fractures. Six years later, with advances in clinical diagnosis and treatment techniques as well as accumulating evidence in related fields, the 2019 guideline requires updating. To this end, the Spinal Trauma Group of Orthopedic Surgeons Branch of Chinese Medical Doctor Association, the Spinal Health Professional Committee of China Human Health Science and Technology Promotion Association, and the Minimally Invasive Orthopedics Professional Committee of Shaanxi Medical Doctor Association have organized experts in the field to develop the Clinical guideline for vertebral augmentation of acute symptomatic osteoporotic thoracolumbar compression fractures ( version 2025) , based on the latest evidence-based medical researches. This guideline incorporates 3 recommendations retained from the 2019 version with updated strength of evidence, along with 12 new recommendations. It provides recommendations from six aspects of diagnosis, pain management, treatment option selection, prevention of postoperative complications, anti-osteoporosis therapy, and postoperative rehabilitation, aiming to provide a reference for standard treatment of vertebral augmentation for ASOTLF in hospitals at all levels.
10.Genomic analysis and multidrug resistance of monophasic Salmonella enterica serovar Typhimurium isolates from Henan
Lingling WU ; Haoyu QI ; Yanfen LI ; Yongli LI ; Jin XU ; Xingguang LIAO ; Xiuli ZHANG ; Zhiwei HAN
Chinese Journal of Laboratory Medicine 2025;48(11):1452-1460
Objective:To analyze the multidrug resistance and genomic characteristics of Monophasic variant of Salmonella enterica serovar Typhimurium (monophasic Salmonella enterica serovar Typhimurium) isolates from clinical patients and food sources in Henan province. Method:A total of 91 monophasic S.Typhimurium strains isolated from clinical and food sources in Henan from 2021 to 2023 were analyzed for antimicrobial sensitivity and underwent whole genome sequencing. Multilocus sequence typing(MLST), multidrug resistance genes and plasmid types were identified using the sequencing data. Phylogenetic tree based on core genome multilocus sequence typing (cgMLST) and single nucleotide polymorphism (SNP) sites was constructed to analyze the genetic evolutionary relationship by comparing with international popular strains in public databases. The Chi-square test was used to compare drug resistance rates. Results:No significant difference was observed in the drug resistance rates between the clinical strains and food strains in Henan [82.19%(60/73) and 11/18, χ2=2.614, P=0.106]. The overall multidrug resistance (MDR) rate was 78.02%(71/91). Most strains were resistant to ampicillin, tetracycline chloramphenicol, β-lactam and sulfonamides. Resistance genes carried by the isolates varied, as well as the drug-resistant phenotypes. MLST showed that 91 strains of S.Typhimurium belonged to ST34 and carried aminoglycoside acetyltransferase gene aac(6′)-Iaa and mobile genetic elements such as plasmids IncQ1 and IncHI2/IncHI2A. The results of cgMLST typing phylogenetic trees showed that food and clinical isolates from the same region in Henan were identified as the same cgST type and clustered in the same branch, which indicated the risk for cross-infection between animal and human. The phylogenetic tree of monophasic S.Typhimurium constructed based on SNP sites showed that the majority of monophasic S.Typhimurium strains in Henan were close to the strains from other provinces in China, other strains were close to the strains from Europe and Southeast Asia, suggesting the possibility of cross regional transmission of the strains. Pork was identified as the main food source. Conclusion:The prevalent ST type of monophasic S.Typhimurium isolated from Henan was ST34, which carried multiple antibiotic resistance genes and widespread drug resistance phenotypes. Most of the monophasic S.Typhimurium isolates in Henan showed a specific phylogenetic lineage with the foreign epidemic strains, indicating the possibility of dissemination of strains between humans and food.

Result Analysis
Print
Save
E-mail