The literature on the characteristics, commodity grade specifications and chemical composition of Angelicae Sinensis Radix was reviewed. It was found that the main factors affecting the changes of traits and chemical composition of Angelicae Sinensis Radix included origin, altitude, climate, soil, cultivation methods, processing and processing methods and storage methods. Among them, the volatile oil types and ferulic acid content of Angelicae Sinensis Radix produced in Minxian County of Gansu Province were better than those in some non-authentic producing areas, but some component differences remained to be verified; direct seeding and film mulching cultivation could improve the yield, volatile oil and polysaccharide content of Angelicae Sinensis Radix; continuous cropping may lead to rhizosphere soil problems of Angelicae Sinensis Radix, and rotation or intercropping could be considered; drying in the shade and smoking drying could retain the oil and aroma of Angelicae Sinensis Radix; wine stir-frying method could increase the content of Z-ligustilide, but stir-frying carbon may reduce the content of ferulic acid; high temperature and high humidity storage may affect the content of ligustilide. In the future, the quality evaluation system of Angelicae Sinensis Radix should be strengthened and improved, genuine research should be strengthened, and scientific field management methods and appropriate harvesting and processing methods should be established, so as to ensure the good clinical efficacy and stable and controllable quality of Angelicae Sinensis Radix.

Objective To analyze the correlation between the number of oil chambers,the proportion of phloem at cross-section of Aucklandiae Radix and the contents of costunolide and dehydrocostuslactone,and the correlation between inulin quantity,vessel quantity and polysaccharide content in powder characteristics,so as to explore the scientific basis for Aucklandiae Radix"identifying the quality based on appearance differentiation".Methods The constant values of the microscopic features of oil chambers,inulin and vessels were determined by cross-sectional permanent slice method,chloral hydrate method and counting analysis method,and the contents of costunolide and dehydrocostuslactone as well as polysaccharide content were determined by the high-performance liquid chromatography(HPLC)and the phenol-sulfuric acid method,respectively,and the correlation in the two groups of data was analyzed by statistical methods.Results There was a significantly positive correlation between the number of oil chambers per unit area in the cross-section of Aucklandiae Radix and the number of oil chambers per unit area in the phloem and the contents of costunolide and dehydrocostuslactone;there was a significantly positive correlation between the quantity of inulin in the powder of Aucklandiae Radix and the polysaccharide content;there was no correlation between the quantity of vessels and the polysaccharide content.Conclusion This study initially established a new method and a new technology for quality evaluation of Chinese herbal medicines based on the determination of microscopic characteristic constants of Aucklandiae Radix,which can provide a new technical method for the quality control of Aucklandiae Radix.

Objective:To analyze the effects of fertilization methods, quality of inner cell mass (ICM) and trophectoderm (TE) on the sex ratio at birth (SRB) during single blastocyst transfer cycles.Methods:5 367 single blastocyst transfer cycles in in vitro fertilization/intracytoplasmic sperm injection and embryo transfer (IVF/ICSI-ET) of patients with successful pregnancy and delivery in Reproductive Medical Center of Zhanjiang Jiuhe Hospital from January 2010 to December 2022 were included in this retrospective cohort study. According to different types of embryos, the cycles were divided into fresh embryo group ( n=1 487, total population; n=1 258, ≤35 years old) and frozen-thawed embryo group ( n=3 880, total population; n=3 199, ≤35 years old). According to different fertilization methods, the cycles were divided into IVF group ( n=4 424, total population; n=3 667, ≤35 years old) and ICSI group ( n=943, total population; n=780, ≤35 years old). Chi-square test was used to analyze the differences of SRB among all the patients and the patients aged ≤35 years who underwent different embryo types and fertilization methods, and logistic regression was used to analyze the effects of ICM and TE ratings on SRB in each group of blastocysts. Results:There were 917 male infants (61.7%, 917/1 487) in the fresh embryo transfer group and 2 317 male infants (59.7%, 2 317/3 880) in frozen-thawed embryo transfer group. The SRB of the fresh embryo transfer group (160.9∶100) was slightly higher than that in frozen-thawed embryo transfer group (148.2∶100), but the difference was not statistically significant ( P=0.201). There were 2 732 male infants (61.8%, 2 732/4 424) in IVF group and 502 male infants (53.2%, 502/943) in ICSI group. The SRB of IVF group (161.5∶100) was significantly higher than that of ICSI group (113.8∶100), and the difference was statistically significant ( P<0.001). In female patients aged ≤35 years, the effects of different embryo transfer methods and different fertilization methods on SRB were consistent with the results of total population. Univariate logistic regression analysis showed that the SRB of patients with ICSI was lower than that of patients with IVF, except for 3-6AA. There were significant differences in SRB between ICSI cycles patients (88.8∶100; 72.8∶100; 156.1∶100) and IVF cycles patients (130.7∶100; 124.8∶100; 206.3∶100) when the blastocyst grade was 3-6BB ( OR=0.679, 95% CI: 0.516-0.896, P=0.006), 3-6AB( OR=0.583, 95% CI: 0.421-0.809, P=0.001) and 3-6BA OR=0.757, 95% CI: 0.585-0.979, P=0.034). Taking 3-6BB blastocysts as reference, the SRB of 3-6AA and 3-6BA blastocysts were higher (IVF: OR=1.527, 95% CI: 1.258-1.854, P<0.001; OR=1.579,95% CI: 1.341-1.859, P<0.001; ICSI: OR=2.566, 95% CI: 1.661-3.966, P<0.001; OR=1.758, 95% CI: 1.250-2.472, P=0.001). Compared with 3-6BA, the SRB of 3-6BC blastocysts was lower (IVF: OR=0.621, 95% CI: 0.447-0.862, P=0.004; ICSI: OR=0.442, 95% CI: 0.238-0.818, P=0.009). Taking 3-6AB as reference, the SRB of 3-6AA blastocysts was higher (IVF: OR=1.600, 95% CI: 1.307-1.958, P<0.001; ICSI: OR=3.130, 95% CI: 1.964-4.987, P<0.001). Conclusion:The SRB of fresh embryo group is slightly higher than that of frozen-thawed group in single blastocyst transfer cycles. Different fertilization methods can affect SRB, and the SRB in IVF is significantly higher than that in ICSI group. The quality of blastocysts can affect SRB, and blastocysts with higher quality TE have significantly increased SRB, while ICM quality have no significant effect on SRB.

Objective:To compare the efficacy of robot system-assisted versus freehand screw revision for ankylosing spondylitis (AS) with lower cervical fractures.Methods:A multicenter retrospective cohort study was conducted to analyze the clinical data of 57 patients with AS combined with lower cervical fractures admitted to Honghui Hospital Affiliated to Xi'an Jiaotong University School of Medicine, Henan Provincial People's Hospital, Zhengzhou Orthopedic Hospital, and Qilu Hospital of Shandong University, including 46 males and 11 females, aged 38-77 years [(65.4±9.5)years]. Injury segments involved C 3 in 7 patients, C 4 in 13, C 5 in 25, C 6 in 10, and C 7 in 2. All the patients underwent revision surgery, among whom, 22 patients were treated with robot system-assisted cervical pedicle screw placement (robot nailing group, with 190 screws), and 35 with freehand cervical pedicle screw placement (freehand nailing group, with 300 screws). The operative duration, intraoperative bleeding volume, frequency of intraoperative fluoroscopy, incision length, and length of hospital stay of the two groups were compared; the time of single nscrew insertion, the number of single nail revisions, the distance between screws and the anterior cortex, the accuracy of screw placement of grade 0 and grade 0+1 were recorded in the two groups. The visual analogue scale (VAS), Japanese Orthopedic Society (JOA) score, neck dysfunction index (NDI), American Spine Injury Association (ASIA) classification before operation, at 3 days, 3 months after operation and at the last follow-up were compared between the two groups. The complication rate was also noted. Results:All the patients were followed up for 12-16 months [(14.3±2.1)months]. The operative duration, intraoperative bleeding volume, and frequency of intraoperative fluoroscopy were (186.4±12.9)minutes, (486.1±68.6)ml, and (3.4±1.3)times in the robot nailing group, which were shorter or less than (206.7±14.4)minutes, (660.3±45.2)ml, and (13.5±3.6)times in the freehand nailing group ( P<0.01). The incision length was (9.4±2.4)cm in the robot nailing group, longer than (5.6±1.2)cm in the freehand nailing group ( P<0.01), and the length of hospital stay was (3.7±0.4)days, shorter than (4.4±1.4)days in the freehand nailing group ( P<0.01). The length of single nail insertion, the number of single nail revision, and the distance between the screws and the front cortex were (6.5±0.4)minutes, (1.1±0.1)times, and (3.5±1.3)mm in the robot nailing group, which were shorter or less than (11.6±0.2)minutes, (1.5±0.2)times, and (12.4±4.7)mm in the freehand nailing group ( P<0.01). The accuracy of the screw placement in the robot nailing group was 90.0% (171/190) and 95.8% (182/190) with level 0 and 0+1 screws, better than 80.0% (240/300) and 89.0% (267/300) in the freehand nailing group ( P<0.05). There was no significant difference in VAS, JOA score, NDI, or ASIA grading between the two groups before operation ( P>0.05). The VAS, JOA, and NDI scores at 3 days after operation were (3.1±0.6)points, (12.1±1.2)points, and (15.6±2.9)points, respectively in the robot nailing group, which were better than (5.0±1.4)points, (11.3±1.1)points and (22.5±3.7)points, respectively in the freehand nailing group ( P<0.05). No statistically significant difference was observed in the ASIA grade between the two groups at 3 days after operation ( P>0.05). There were no significant differences in VAS, JOA, NDI scores, or ASIA grading between the two groups at 3 months after operation and at the last follow-up ( P>0.05). Compared with those before operation, the VAS, JOA, NDI scores, and ASIA grading were significantly improved at 3 days, 3 months after operation and at the last follow-up in the two groups, which were further improved with the passage of time. Two patients in the robot nailing group had pneumonia, with a complication rate of 9% (2/22), while 2 patients in the freehand nailing group had dural sac rupture and cerebrospinal fluid leakage and 3 had lung infection after operation, with a complication rate of 14% (5/35) ( P<0.05). Conclusion:Compared with freehand nailing, the robot system-assisted nailing revision for AS with lower cervical fracture has more advantages in terms of the operative duration, length of hospital stay, intraoperative bleeding volume, frequency of intraoperative fluoroscopy nailing speed and accuracy, screw holding force, early pain relief, function restoration, and complication rate, despite longer surgical incision.

Objective:To investigate the brain iron status in the sensorimotor cortex of patients with chronic low back pain (CLBP) and its relationship with changes in resting-state functional connectivity (RS-FC).Methods:This was a cross-sectional study. Thirty-two patients with CLBP (CLBP group) who were treated at Wuxi People′s Hospital Affiliated to Nanjing Medical University from July 2023 to March 2024 and 30 age-and gender-matched healthy volunteers (control group) were prospectively included. All subjects underwent pain and neuropsychological assessments and head MRI examinations, including conventional sequences, quantitative susceptibility mapping (QSM), and blood oxygen level-dependent (BOLD) functional MRI. QSM values of the sensorimotor cortex and the left middle frontal gyrus, right inferior temporal gyrus, right olfactory cortex, and right posterior cingulate gyrus were extracted using the ANTs toolkit. The bilateral postcentral gyrus and posterior portion of the bilateral precentral gyrus in the sensorimotor cortex were selected as seed points using SPM software to extract the average time series of BOLD signals and evaluate the changes in RS-FC values with other brain regions. Two-sample t-tests were used to compare the differences in QSM values and RS-FC values between the two groups. Pearson correlation analysis was used to analyze the correlation between iron deposition in key brain regions and RS-FC values and clinical scale scores. Results:The QSM values in the posterior portion of the bilateral precentral gyrus and the left postcentral gyrus in the CLBP group were significantly higher than those in the control group ( t=2.17, P=0.009; t=4.44, P<0.001), and the QSM value in the left postcentral gyrus was positively correlated with pain-related scale scores ( P<0.05). Compared with the control group, the QSM values in the left orbital part of the middle frontal gyrus ( t=2.22, P=0.031) and the right inferior temporal gyrus ( t=2.98, P=0.004) were increased, while the QSM values in the right olfactory cortex ( t=2.54, P=0.014) and the right posterior cingulate gyrus ( t=2.70, P=0.009) were decreased in the CLBP group. Compared with the control group, the RS-FC values between the left postcentral gyrus, the posterior part of the bilateral precentral gyrus, and the left superior frontal gyrus were increased in the CLBP group ( P<0.001), the RS-FC value between the right postcentral gyrus and the right precuneus was increased ( P<0.001). The RS-FC of the bilateral motor cortex and the left dorsolateral superior frontal gyrus was positively correlated with the QSM values of the bilateral motor cortex ( r=0.444, P=0.015). Conclusion:Iron deposition in the sensorimotor cortex (posterior portion of the bilateral precentral gyrus and the left postcentral gyrus) is increased in CLBP patients and is correlated with abnormal functional connectivity within and between brain regions.

Objective:To analyze the effects of fertilization methods, quality of inner cell mass (ICM) and trophectoderm (TE) on the sex ratio at birth (SRB) during single blastocyst transfer cycles.Methods:5 367 single blastocyst transfer cycles in in vitro fertilization/intracytoplasmic sperm injection and embryo transfer (IVF/ICSI-ET) of patients with successful pregnancy and delivery in Reproductive Medical Center of Zhanjiang Jiuhe Hospital from January 2010 to December 2022 were included in this retrospective cohort study. According to different types of embryos, the cycles were divided into fresh embryo group ( n=1 487, total population; n=1 258, ≤35 years old) and frozen-thawed embryo group ( n=3 880, total population; n=3 199, ≤35 years old). According to different fertilization methods, the cycles were divided into IVF group ( n=4 424, total population; n=3 667, ≤35 years old) and ICSI group ( n=943, total population; n=780, ≤35 years old). Chi-square test was used to analyze the differences of SRB among all the patients and the patients aged ≤35 years who underwent different embryo types and fertilization methods, and logistic regression was used to analyze the effects of ICM and TE ratings on SRB in each group of blastocysts. Results:There were 917 male infants (61.7%, 917/1 487) in the fresh embryo transfer group and 2 317 male infants (59.7%, 2 317/3 880) in frozen-thawed embryo transfer group. The SRB of the fresh embryo transfer group (160.9∶100) was slightly higher than that in frozen-thawed embryo transfer group (148.2∶100), but the difference was not statistically significant ( P=0.201). There were 2 732 male infants (61.8%, 2 732/4 424) in IVF group and 502 male infants (53.2%, 502/943) in ICSI group. The SRB of IVF group (161.5∶100) was significantly higher than that of ICSI group (113.8∶100), and the difference was statistically significant ( P<0.001). In female patients aged ≤35 years, the effects of different embryo transfer methods and different fertilization methods on SRB were consistent with the results of total population. Univariate logistic regression analysis showed that the SRB of patients with ICSI was lower than that of patients with IVF, except for 3-6AA. There were significant differences in SRB between ICSI cycles patients (88.8∶100; 72.8∶100; 156.1∶100) and IVF cycles patients (130.7∶100; 124.8∶100; 206.3∶100) when the blastocyst grade was 3-6BB ( OR=0.679, 95% CI: 0.516-0.896, P=0.006), 3-6AB( OR=0.583, 95% CI: 0.421-0.809, P=0.001) and 3-6BA OR=0.757, 95% CI: 0.585-0.979, P=0.034). Taking 3-6BB blastocysts as reference, the SRB of 3-6AA and 3-6BA blastocysts were higher (IVF: OR=1.527, 95% CI: 1.258-1.854, P<0.001; OR=1.579,95% CI: 1.341-1.859, P<0.001; ICSI: OR=2.566, 95% CI: 1.661-3.966, P<0.001; OR=1.758, 95% CI: 1.250-2.472, P=0.001). Compared with 3-6BA, the SRB of 3-6BC blastocysts was lower (IVF: OR=0.621, 95% CI: 0.447-0.862, P=0.004; ICSI: OR=0.442, 95% CI: 0.238-0.818, P=0.009). Taking 3-6AB as reference, the SRB of 3-6AA blastocysts was higher (IVF: OR=1.600, 95% CI: 1.307-1.958, P<0.001; ICSI: OR=3.130, 95% CI: 1.964-4.987, P<0.001). Conclusion:The SRB of fresh embryo group is slightly higher than that of frozen-thawed group in single blastocyst transfer cycles. Different fertilization methods can affect SRB, and the SRB in IVF is significantly higher than that in ICSI group. The quality of blastocysts can affect SRB, and blastocysts with higher quality TE have significantly increased SRB, while ICM quality have no significant effect on SRB.

Objective:To compare the efficacy of robot system-assisted versus freehand screw revision for ankylosing spondylitis (AS) with lower cervical fractures.Methods:A multicenter retrospective cohort study was conducted to analyze the clinical data of 57 patients with AS combined with lower cervical fractures admitted to Honghui Hospital Affiliated to Xi'an Jiaotong University School of Medicine, Henan Provincial People's Hospital, Zhengzhou Orthopedic Hospital, and Qilu Hospital of Shandong University, including 46 males and 11 females, aged 38-77 years [(65.4±9.5)years]. Injury segments involved C 3 in 7 patients, C 4 in 13, C 5 in 25, C 6 in 10, and C 7 in 2. All the patients underwent revision surgery, among whom, 22 patients were treated with robot system-assisted cervical pedicle screw placement (robot nailing group, with 190 screws), and 35 with freehand cervical pedicle screw placement (freehand nailing group, with 300 screws). The operative duration, intraoperative bleeding volume, frequency of intraoperative fluoroscopy, incision length, and length of hospital stay of the two groups were compared; the time of single nscrew insertion, the number of single nail revisions, the distance between screws and the anterior cortex, the accuracy of screw placement of grade 0 and grade 0+1 were recorded in the two groups. The visual analogue scale (VAS), Japanese Orthopedic Society (JOA) score, neck dysfunction index (NDI), American Spine Injury Association (ASIA) classification before operation, at 3 days, 3 months after operation and at the last follow-up were compared between the two groups. The complication rate was also noted. Results:All the patients were followed up for 12-16 months [(14.3±2.1)months]. The operative duration, intraoperative bleeding volume, and frequency of intraoperative fluoroscopy were (186.4±12.9)minutes, (486.1±68.6)ml, and (3.4±1.3)times in the robot nailing group, which were shorter or less than (206.7±14.4)minutes, (660.3±45.2)ml, and (13.5±3.6)times in the freehand nailing group ( P<0.01). The incision length was (9.4±2.4)cm in the robot nailing group, longer than (5.6±1.2)cm in the freehand nailing group ( P<0.01), and the length of hospital stay was (3.7±0.4)days, shorter than (4.4±1.4)days in the freehand nailing group ( P<0.01). The length of single nail insertion, the number of single nail revision, and the distance between the screws and the front cortex were (6.5±0.4)minutes, (1.1±0.1)times, and (3.5±1.3)mm in the robot nailing group, which were shorter or less than (11.6±0.2)minutes, (1.5±0.2)times, and (12.4±4.7)mm in the freehand nailing group ( P<0.01). The accuracy of the screw placement in the robot nailing group was 90.0% (171/190) and 95.8% (182/190) with level 0 and 0+1 screws, better than 80.0% (240/300) and 89.0% (267/300) in the freehand nailing group ( P<0.05). There was no significant difference in VAS, JOA score, NDI, or ASIA grading between the two groups before operation ( P>0.05). The VAS, JOA, and NDI scores at 3 days after operation were (3.1±0.6)points, (12.1±1.2)points, and (15.6±2.9)points, respectively in the robot nailing group, which were better than (5.0±1.4)points, (11.3±1.1)points and (22.5±3.7)points, respectively in the freehand nailing group ( P<0.05). No statistically significant difference was observed in the ASIA grade between the two groups at 3 days after operation ( P>0.05). There were no significant differences in VAS, JOA, NDI scores, or ASIA grading between the two groups at 3 months after operation and at the last follow-up ( P>0.05). Compared with those before operation, the VAS, JOA, NDI scores, and ASIA grading were significantly improved at 3 days, 3 months after operation and at the last follow-up in the two groups, which were further improved with the passage of time. Two patients in the robot nailing group had pneumonia, with a complication rate of 9% (2/22), while 2 patients in the freehand nailing group had dural sac rupture and cerebrospinal fluid leakage and 3 had lung infection after operation, with a complication rate of 14% (5/35) ( P<0.05). Conclusion:Compared with freehand nailing, the robot system-assisted nailing revision for AS with lower cervical fracture has more advantages in terms of the operative duration, length of hospital stay, intraoperative bleeding volume, frequency of intraoperative fluoroscopy nailing speed and accuracy, screw holding force, early pain relief, function restoration, and complication rate, despite longer surgical incision.

OBJECTIVE To analyze the distribution and drug resistance of pathogenic bacteria in hospital-associat-ed infections for patients after renal transplantation,and to provide a reference for the rational selection of antibac-terial drugs for anti-infective treatment in such patients.METHODS Clinical data were collected from 89 hospital-ized patients who underwent renal transplantation and developed hospital-associated infection at Beidaihe Rehabili-tation and Recuperation Center(formerly known as 281 Hospital)from 2017 to 2021.The pathogenic bacteria de-tected in different types of hospital-associated infections and the drug resistance of the main pathogenic bacteria were analyzed.RESULTS A total of 89 pathogenic bacterial strains were isolated from the 89 patients with hospi-tal-associated infection,including 74 gram-negative bacterial strains(83.15％)and 15 gram-positive bacterial strains(16.85％).The predominant pathogenic bacterial strains were Klebsiella pneumoniae,Escherichia coli and Pseudomonas aeruginosa.Respiratory tract infection was the most common.E.coli showed severe drug re-sistance,with high drug resistance rates to various antibacterial drugs(complete drug resistance to piperacillin and ampicillin).K.pneumoniae was generally drug resistant to ampicillin.Enterobacter cloacae showed high sensitivi-ty to carbapenems,amikacin and enzyme inhibitor combinations.P.aeruginosa had low drug resistance rates to imipenem and meropenem.Staphylococcus aureus was completely drug resistant to antibacterial drugs such as penicillin,erythromycin and gentamicin,and no drug-resistant strains to vancomycin and linezolid were found.CONCLUSIONS The gram-negative bacteria are dominant among the bacteria isolated from the renal trans-planted patients with postoperative hospital-associated infections,with a high detection rate of E.coli and a severe drug resistance situation.Therefore,it is necessary to strengthen the monitoring of drug resistance in renal trans-plant recipients and make rational choices of antibacterial drugs.

Objective To explore the efficacy of the self-formulated Zhuzhang Formula in trea-ting the spleen deficiency with dysfunction of transportation syndrome of idiopathic short stature(ISS)and its effects on the growth rate,disease-related indicators,and bone metabolism indicators in affect-ed children.Methods A total of 80 children with ISS were enrolled as study subjects.They were randomly assigned to control group and observation group using random number table method,with 40 cases in each group.The control group received conventional western medicine treatment,while the observation group was administered self-formulated Zhuzhang Formula in addition to the treatment of the control group.Comparisons were made between the two groups in terms of clinical efficacy,TCM syndrome scores,growth parameters(monthly average height increment,annual growth rate),levels of disease-related indicators[serum insulin-like growth factor-1(IGF-1),bone morphogenetic pro-tein-2(BMP-2),insulin-like growth factor binding protein-3(IGFBP-3)],levels of bone metabo-lism indicators[bone alkaline phosphatase(BAP),type Ⅰ procollagen N-terminal propeptide(PⅠNP),type Ⅰ collagen cross-linked C-terminal telopeptide(β-CTX)],and the incidence of adverse reac-tions.Results The overall effective rate in the observation group was 97.50％,which was significantly higher than the 80.00％ in the control group(P＜0.05).After 3 and 6 months of intervention,the scores for symptoms such as short stature,sallow complexion,loss of appetite,weak voice and shortness of breath,limb weakness,and loose stools,as well as the total TCM syndrome scores,were lower in the observation group than those in the control group,with statistically significant differences(P＜0.05).After 6 months of intervention,the monthly average height increment and annual growth rate were higher in the observation group than those in the control group,and the differences were statistically significant(P＜0.05).After 3 and 6 months of intervention,the levels of IGF-1,BMP-2,IGFBP-3,BAP,and PⅠNP were higher in the observation group than those in the control group,while the level of β-CTX was lower,and the differences were statistically significant(P＜0.05).There was no statistically significant difference in the incidence of adverse reactions between the two groups(P＞0.05).Conclusion The self-formulated Zhuchang Formula demon-strates remarkable efficacy in treating the spleen deficiency with dysfunction of transportation syndrome of ISS.It can alleviate clinical symptoms by regulating the levels of IGF-1,BMP-2,IGFBP-3,and bone metabolism indicators,thereby promoting the growth and development of affected children,and exhibits high safety.

Objective:To investigate the brain iron status in the sensorimotor cortex of patients with chronic low back pain (CLBP) and its relationship with changes in resting-state functional connectivity (RS-FC).Methods:This was a cross-sectional study. Thirty-two patients with CLBP (CLBP group) who were treated at Wuxi People′s Hospital Affiliated to Nanjing Medical University from July 2023 to March 2024 and 30 age-and gender-matched healthy volunteers (control group) were prospectively included. All subjects underwent pain and neuropsychological assessments and head MRI examinations, including conventional sequences, quantitative susceptibility mapping (QSM), and blood oxygen level-dependent (BOLD) functional MRI. QSM values of the sensorimotor cortex and the left middle frontal gyrus, right inferior temporal gyrus, right olfactory cortex, and right posterior cingulate gyrus were extracted using the ANTs toolkit. The bilateral postcentral gyrus and posterior portion of the bilateral precentral gyrus in the sensorimotor cortex were selected as seed points using SPM software to extract the average time series of BOLD signals and evaluate the changes in RS-FC values with other brain regions. Two-sample t-tests were used to compare the differences in QSM values and RS-FC values between the two groups. Pearson correlation analysis was used to analyze the correlation between iron deposition in key brain regions and RS-FC values and clinical scale scores. Results:The QSM values in the posterior portion of the bilateral precentral gyrus and the left postcentral gyrus in the CLBP group were significantly higher than those in the control group ( t=2.17, P=0.009; t=4.44, P<0.001), and the QSM value in the left postcentral gyrus was positively correlated with pain-related scale scores ( P<0.05). Compared with the control group, the QSM values in the left orbital part of the middle frontal gyrus ( t=2.22, P=0.031) and the right inferior temporal gyrus ( t=2.98, P=0.004) were increased, while the QSM values in the right olfactory cortex ( t=2.54, P=0.014) and the right posterior cingulate gyrus ( t=2.70, P=0.009) were decreased in the CLBP group. Compared with the control group, the RS-FC values between the left postcentral gyrus, the posterior part of the bilateral precentral gyrus, and the left superior frontal gyrus were increased in the CLBP group ( P<0.001), the RS-FC value between the right postcentral gyrus and the right precuneus was increased ( P<0.001). The RS-FC of the bilateral motor cortex and the left dorsolateral superior frontal gyrus was positively correlated with the QSM values of the bilateral motor cortex ( r=0.444, P=0.015). Conclusion:Iron deposition in the sensorimotor cortex (posterior portion of the bilateral precentral gyrus and the left postcentral gyrus) is increased in CLBP patients and is correlated with abnormal functional connectivity within and between brain regions.