Objective:To explore the effects of posterior malleolar fracture fixation on the rotational stability of the ankle joint.Methods:A total of 20 fresh cadaveric specimens of lower limbs were anatomized to measure the area of attachment of the posterior inferior tibiofibular ligament and transverse ligament complex to the posterior surface of the tibia. One healthy volunteer was selected to construct a finite element model for the intact tibiofibular and ankle joints and finite element models for posterior malleolar fracture with different posterior projection areas. A load of 600 N was vertically applied to the inferior calcaneus along the tibial mechanical axis. The contact area and maximum Von Mises stress of the distal tibial articular surface were analyzed to verify the validity of the model for the intact tibiofibular and ankle joints. In the finite element models for the posterior malleolar fracture (S, 1/2S, 1/4S, 1/8S and 1/16S model groups, with S standing for the complete projection area of the ligament complex on the posterior surface of the tibia), the width increase in the tibiofibular clear space was measured when a vertical load of 600 N and external rotation load of 5 N·m were applied to the ankle joint after the reduction and fixation of posterior malleolar fracture. The cutoff value of the posterior projection area of posterior malleolar fracture that could maintain the rotational stability of the ankle joint was assessed.Results:The measurement results of the cadaveric specimens showed that the area of attachment of the posterior inferior tibiofibular ligament and transverse ligament complex to the posterior surface of the tibia was relatively large. It was attached to the posterolateral area of the distal tibia with the highest point located at (45.2±5.6)mm from the articular surface. With the increase in the distance from the joint line, the width of the posterior attachment area of the ligament complex was decreased. Results of the finite element analysis showed that in the finite element model for the intact tibiofibular and ankle joints, the tibiotalar joint contact area was 324.02 mm 2 and the maximum Von Mises stress was 4.495 1 MPa with a vertical load of 600 N. In the finite element models for the posterior malleolar fracture, the distal tibiofibular clear spaces of the S, 1/2S, 1/4S and 1/8S model groups increased by less than 2 mm following loading, while it was increased by 3.445 8 mm in the 1/16S model group. The cutoff value of the posterior tibial projection area that could maintain the rotational stability of the ankle joint was 1/8S. Conclusions:The attachment area of the posterior inferior tibiofibular ligament and transverse ligament complex to the posterior surface of the tibia is large. Both the axial stability and rotational stability of the ankle joint should be considered in the treatment selection for posterior malleolar fracture. Simple posterior malleolar fixation is recommended to restore the rotational stability and axial stability of the ankle joint when tibiofibular syndesmosis is unstable and the cutoff value is larger than or equal to 1/8, while tibiofibular syndesmosis screws must be implanted when tibiofibular syndesmosis is unstable and the cutoff value is less than 1/8.

AIM To investigate the effects of total Astragalus saponins on the improvement of sarcopenia in a rat model of type 2 diabetes mellitus(T2DM).METHODS The rats were divided into the normal group for a normal feeding and the model group for the feeding of high-sugar and high-fat diet combined with intraperitoneal injection of STZ to establish a T2DM model.The successful model rats were randomly divided into the model group,the metformin group(0.2 g/kg)and the total Astragalus saponins group(80 mg/kg),and given corresponding doses of drugs by gavage.After 12 weeks administration,the rats had their FBG,postprandial blood glucose(PG2h)and wet weight of skeletal muscle measured;their serum levels of INS,C-peptide(C-P),IGF-1,TNF-α and IL-1β detected by ELISA;their morphological changes of skeletal muscle observed by HE staining;their protein expressions of PI3K,p-Akt,mTOR,S6K1,FoxO1 and Murf1 in skeletal muscle detected by Western blot;and their mRNA expressions of Pi3k,Akt and mtor in skeletal muscle detected by RT-qPCR method.RESULTS Compared with the model group,the total Astragalus saponins group displayed decreased levels of FBG,PG2h,OGTT-AUC,HOMA-IR,TNF-α and IL-1β(P＜0.01);increased levels of INS,C-P,IGF-1 and wet weight of skeletal muscle(P＜0.05,P＜0.01);improved skeletal muscle atrophy and increased protein expressions of PI3K,p-Akt,mTOR and S6K1 in skeletal muscle(P＜0.05,P＜0.01);decreased protein expressions of FoxO1 and Murf1(P＜0.05,P＜0.01);and increased mRNA expressions of Pi3k,Akt and mtor(P＜0.01).CONCLUSION The improvement effects of total Astragalus saponins on sarcopenia in T2DM rats may be associated with the regulation of PI3K/Akt/mTOR and PI3K/Akt/FoxO1 pathways.

To investigate the alleviating effect of glycyrrhizic acid(GA)on chronic toxicity of afla-toxin B1(AFB1)in ducklings.Eighty 4-day-old ducklings were randomly divided into 4 groups,with 20 ducklings in each group,including a blank group,a model group(100 μg/kg AFB1),a high-concentration GA group(100 μg/kg AFB1+100 mg/kg GA),and a low-concentration GA group(100 μg/kg AFB1+50 mg/kg GA),with a trial period of 18 days.At the end of the experi-ment,the body weight of the ducklings in each group,AFB1-DNA content in the liver and liver tis-sues index,the biochemical indicators of liver function,and the pathological changes in liver tissues were examined.Additionally,the oxidative damage status of the liver tissues was eval-uated,and the mRNA expression levels of mitochondria-related apoptosis genes was detected.Com-pared with the control group,the body weight of ducklings in the model group decreased signifi-cantly(P＜0.01),AFB1-DNA content in the tissues increased significantly(P＜0.05),liver swell-ing and yellowing were observed,the liver index increased significantly(P＜0.01),as did the levels of aspartate aminotransferase(AST)and alanine aminotransferase(ALT)(P＜0.01).The AST/ALT levels also increased significantly(P＜0.01),while the serum total protein(TP)content de-creased significantly(P＜0.01).The liver tissues showed a large amount of inflammatory cell infil-tration,vacuolar degeneration,fibrotic changes and apoptosis.The activities of catalase(CAT),glutathione S-transferase(GST),the total antioxidant capacity(T-AOC)of the duckling liver all decreased significantly(P＜0.01)and the mRNA expression of mitochondria-related apoptosis genes Bax,Cyt-c,Caspase-3,and Caspase-9 significantly increased(P＜0.01).Compared with the model group,GA treatment significantly increased the body weight of the model ducklings(P＜0.01),reduced AFB1-DNA content in the tissue,significantly reduced their liver index(P＜0.05),visibly restored the liver's apparent status,effectively reversed the abnormal changes in serum liver function indicators,improved the pathological changes in liver tissue histology,enhanced liver an-tioxidant function,significantly decreased expression of Bax,Cyt-c,Caspase-3,and Caspase-9 mR-NA(P＜0.05).Further correlation analysis showed that mRNA expression levels of Bax,Cyt-c,Caspase-3,and Caspase-9 in duck liver tissues were positively correlated with liver index,AFB1-DNA content,AST content,ALT content,AST/ALT ratio,and MDA content,and negatively cor-related with body weight,TP content,SOD activity,CAT activity,GST activity,and T-AOC activi-ty in ducklings.In conclusion,GA may alleviate liver damage to relieve duckling AFB1 chronic tox-icity by inhibiting the mitochondrial pathway of apoptosis.

Objective:To investigate the risk factors for severe hyperbilirubinemia complicated by acute bilirubin encephalopathy (ABE), and the value of total serum bilirubin (TSB) and bilirubin (B)/albumin (A) ratio in predicting ABE.Methods:Clinical data of children with severe hyperbilirubinemia admitted to the Affiliated Hospital of Inner Mongolia Medical University, Ordos Central Hospital, People's Hospital of Inner Mongolia Autonomous Region, the Fourth Hospital of Baotou, Tongliao Hospital, Maternal and Child Health Hospital of Hohhot, the Affiliated Hospital of Chifeng University, Manzhouli People's Hospital, and Chifeng Hospital from January 1, 2020, to December 31, 2021, were retrospectively collected. The subjects were divided into ABE and non-ABE groups based on the occurrence of ABE. Multivariate logistic regression analysis was used to identify high-risk factors for ABE. Statistical analysis was performed using t-test, Wilcoxon signed-rank test, or Chi-square tests. Indicators with statistically significant differences were included in the multivariate logistic regression model, and stepwise regression was used to analyze the influencing factors of ABE. Results:(1) A total of 543 children were included in this study, accounting for 3.7% (543/14 831) of the total admissions during the same period. Among the 543 children, 81 (14.9%) had ABE, and 462 (85.1%) did not. The age at admission was (7.2±2.1) d, and the length of hospital stay was (5.2±2.2) d. The breastfeeding initiation time was 2 d (1-4 d) after birth. The peak TSB of the 543 cases was (385.98±51.22) μmol/L, and the age at peak TSB was (4.4±2.1) d. Fourteen cases (2.5%) gradually reached the peak TSB after admission [(392.01±61.24) μmol/L], while 529 cases (97.5%) had already reached the peak TSB at admission [(386.42±50.22) μmol/L]. Among the 543 cases, 356 had a clear etiology (65.6%, with 278 cases having a single cause and 78 cases having more than two causes), and 187 cases (34.4%) had an unknown etiology. (2) Compared with the non-ABE group, the breastfeeding initiation in the ABE group was later [6 h (2-6 h) vs. 2 h (1-3 h), Z=－6.87] and the length of hospital stay was longer [(6.5±1.9) d vs. (5.0±2.1) d, t=0.55]. The proportions of breastfeeding, delayed meconium passage, isoimmune hemolysis, and maternal gestational diabetes, as well as peak TSB and B/A ratio at peak TSB, were higher in the ABE group than in the non-ABE group [64.2% (52/81) vs. 36.8% (170/462), χ2=21.96; 16.0% (13/81) vs. 2.4% (11/462), χ2=27.32; 27.2% (22/81) vs. 10.6% (40/462), χ2=16.61; 24.7% (20/81) vs. 13.6% (63/462), χ2=6.50; (442±68) vs. (375±39) μmol/L, t=－8.55; (11.9±1.6) vs. (9.8±1.2), t=－11.61; all P<0.05]. The admission weight, proportion of transfer from the hospital's obstetrics department, unknown etiology, and breast milk jaundice were lower in the ABE group than in the non-ABE group [(3 098±482) vs. (3 278±493) g, t=3.04; 12.3% (10/81) vs. 42.4% (196/462), χ2=30.48; 3.7% (3/81) vs. 39.8% (184/462), χ2=39.83; 0.0% (0/81) vs. 5.8% (27/462), χ2=3.81; all P<0.05]. (3) Isoimmune hemolysis, peak TSB, and B/A ratio at peak TSB were independent risk factors for ABE [ OR(95% CI) were 2.924 (1.209-7.073), 1.006 (0.997-1.014), and 2.647 (1.841-3.805), respectively]. When the peak TSB was 380.05 μmol/L and the B/A ratio at peak TSB was 10.45, the sensitivity for predicting ABE was 0.963, the specificity was 0.789, and the area under the receiver operating characteristic curve was 0.752. Conclusions:Isoimmune hemolysis, peak TSB, and B/A ratio at peak TSB are independent risk factors for ABE. The B/A ratio at peak TSB and peak TSB can effectively predict ABE.

Objective:To investigate the risk factors for severe hyperbilirubinemia complicated by acute bilirubin encephalopathy (ABE), and the value of total serum bilirubin (TSB) and bilirubin (B)/albumin (A) ratio in predicting ABE.Methods:Clinical data of children with severe hyperbilirubinemia admitted to the Affiliated Hospital of Inner Mongolia Medical University, Ordos Central Hospital, People's Hospital of Inner Mongolia Autonomous Region, the Fourth Hospital of Baotou, Tongliao Hospital, Maternal and Child Health Hospital of Hohhot, the Affiliated Hospital of Chifeng University, Manzhouli People's Hospital, and Chifeng Hospital from January 1, 2020, to December 31, 2021, were retrospectively collected. The subjects were divided into ABE and non-ABE groups based on the occurrence of ABE. Multivariate logistic regression analysis was used to identify high-risk factors for ABE. Statistical analysis was performed using t-test, Wilcoxon signed-rank test, or Chi-square tests. Indicators with statistically significant differences were included in the multivariate logistic regression model, and stepwise regression was used to analyze the influencing factors of ABE. Results:(1) A total of 543 children were included in this study, accounting for 3.7% (543/14 831) of the total admissions during the same period. Among the 543 children, 81 (14.9%) had ABE, and 462 (85.1%) did not. The age at admission was (7.2±2.1) d, and the length of hospital stay was (5.2±2.2) d. The breastfeeding initiation time was 2 d (1-4 d) after birth. The peak TSB of the 543 cases was (385.98±51.22) μmol/L, and the age at peak TSB was (4.4±2.1) d. Fourteen cases (2.5%) gradually reached the peak TSB after admission [(392.01±61.24) μmol/L], while 529 cases (97.5%) had already reached the peak TSB at admission [(386.42±50.22) μmol/L]. Among the 543 cases, 356 had a clear etiology (65.6%, with 278 cases having a single cause and 78 cases having more than two causes), and 187 cases (34.4%) had an unknown etiology. (2) Compared with the non-ABE group, the breastfeeding initiation in the ABE group was later [6 h (2-6 h) vs. 2 h (1-3 h), Z=－6.87] and the length of hospital stay was longer [(6.5±1.9) d vs. (5.0±2.1) d, t=0.55]. The proportions of breastfeeding, delayed meconium passage, isoimmune hemolysis, and maternal gestational diabetes, as well as peak TSB and B/A ratio at peak TSB, were higher in the ABE group than in the non-ABE group [64.2% (52/81) vs. 36.8% (170/462), χ2=21.96; 16.0% (13/81) vs. 2.4% (11/462), χ2=27.32; 27.2% (22/81) vs. 10.6% (40/462), χ2=16.61; 24.7% (20/81) vs. 13.6% (63/462), χ2=6.50; (442±68) vs. (375±39) μmol/L, t=－8.55; (11.9±1.6) vs. (9.8±1.2), t=－11.61; all P<0.05]. The admission weight, proportion of transfer from the hospital's obstetrics department, unknown etiology, and breast milk jaundice were lower in the ABE group than in the non-ABE group [(3 098±482) vs. (3 278±493) g, t=3.04; 12.3% (10/81) vs. 42.4% (196/462), χ2=30.48; 3.7% (3/81) vs. 39.8% (184/462), χ2=39.83; 0.0% (0/81) vs. 5.8% (27/462), χ2=3.81; all P<0.05]. (3) Isoimmune hemolysis, peak TSB, and B/A ratio at peak TSB were independent risk factors for ABE [ OR(95% CI) were 2.924 (1.209-7.073), 1.006 (0.997-1.014), and 2.647 (1.841-3.805), respectively]. When the peak TSB was 380.05 μmol/L and the B/A ratio at peak TSB was 10.45, the sensitivity for predicting ABE was 0.963, the specificity was 0.789, and the area under the receiver operating characteristic curve was 0.752. Conclusions:Isoimmune hemolysis, peak TSB, and B/A ratio at peak TSB are independent risk factors for ABE. The B/A ratio at peak TSB and peak TSB can effectively predict ABE.

To investigate the alleviating effect of glycyrrhizic acid(GA)on chronic toxicity of afla-toxin B1(AFB1)in ducklings.Eighty 4-day-old ducklings were randomly divided into 4 groups,with 20 ducklings in each group,including a blank group,a model group(100 μg/kg AFB1),a high-concentration GA group(100 μg/kg AFB1+100 mg/kg GA),and a low-concentration GA group(100 μg/kg AFB1+50 mg/kg GA),with a trial period of 18 days.At the end of the experi-ment,the body weight of the ducklings in each group,AFB1-DNA content in the liver and liver tis-sues index,the biochemical indicators of liver function,and the pathological changes in liver tissues were examined.Additionally,the oxidative damage status of the liver tissues was eval-uated,and the mRNA expression levels of mitochondria-related apoptosis genes was detected.Com-pared with the control group,the body weight of ducklings in the model group decreased signifi-cantly(P＜0.01),AFB1-DNA content in the tissues increased significantly(P＜0.05),liver swell-ing and yellowing were observed,the liver index increased significantly(P＜0.01),as did the levels of aspartate aminotransferase(AST)and alanine aminotransferase(ALT)(P＜0.01).The AST/ALT levels also increased significantly(P＜0.01),while the serum total protein(TP)content de-creased significantly(P＜0.01).The liver tissues showed a large amount of inflammatory cell infil-tration,vacuolar degeneration,fibrotic changes and apoptosis.The activities of catalase(CAT),glutathione S-transferase(GST),the total antioxidant capacity(T-AOC)of the duckling liver all decreased significantly(P＜0.01)and the mRNA expression of mitochondria-related apoptosis genes Bax,Cyt-c,Caspase-3,and Caspase-9 significantly increased(P＜0.01).Compared with the model group,GA treatment significantly increased the body weight of the model ducklings(P＜0.01),reduced AFB1-DNA content in the tissue,significantly reduced their liver index(P＜0.05),visibly restored the liver's apparent status,effectively reversed the abnormal changes in serum liver function indicators,improved the pathological changes in liver tissue histology,enhanced liver an-tioxidant function,significantly decreased expression of Bax,Cyt-c,Caspase-3,and Caspase-9 mR-NA(P＜0.05).Further correlation analysis showed that mRNA expression levels of Bax,Cyt-c,Caspase-3,and Caspase-9 in duck liver tissues were positively correlated with liver index,AFB1-DNA content,AST content,ALT content,AST/ALT ratio,and MDA content,and negatively cor-related with body weight,TP content,SOD activity,CAT activity,GST activity,and T-AOC activi-ty in ducklings.In conclusion,GA may alleviate liver damage to relieve duckling AFB1 chronic tox-icity by inhibiting the mitochondrial pathway of apoptosis.

Glioblastoma multiforme (GBM), a highly malignant and heterogeneous brain tumor, contains various types of tumor and non-tumor cells. Whether GBM cells can trans-differentiate into non-neural cell types, including mural cells or endothelial cells (ECs), to support tumor growth and invasion remains controversial. Here we generated two genetic GBM models de novo in immunocompetent mouse brains, mimicking essential pathological and molecular features of human GBMs. Lineage-tracing and transplantation studies demonstrated that, although blood vessels in GBM brains underwent drastic remodeling, evidence of trans-differentiation of GBM cells into vascular cells was barely detected. Intriguingly, GBM cells could promiscuously express markers for mural cells during gliomagenesis. Furthermore, single-cell RNA sequencing showed that patterns of copy number variations (CNVs) of mural cells and ECs were distinct from those of GBM cells, indicating discrete origins of GBM cells and vascular components. Importantly, single-cell CNV analysis of human GBM specimens also suggested that GBM cells and vascular cells are likely separate lineages. Rather than expansion owing to trans-differentiation, vascular cell expanded by proliferation during tumorigenesis. Therefore, cross-lineage trans-differentiation of GBM cells is very unlikely to occur during gliomagenesis. Our findings advance understanding of cell lineage dynamics during gliomagenesis, and have implications for targeted treatment of GBMs.
Mice ; Animals ; Humans ; Glioblastoma/pathology* ; Endothelial Cells/pathology* ; DNA Copy Number Variations ; Brain/metabolism* ; Brain Neoplasms/pathology*

This study aims to investigate the effect and mechanism of total triterpenes of Euphorbium in treating rheumatoid arthritis(RA). The rat model of RA was established with Freund's complete adjuvant(FCA). Male rats were randomly assigned into control, model, Tripterygium glycosides(7.5 mg·kg~(-1)), and low-, medium-, and high-dose total triterpenes of Euphorbium(32, 64, and 128 mg·kg~(-1), respectively) groups, with 10 rats in each group. In other groups except the control group, 0.2 mL FCA was injected into the right hind toe. Rats in the intervention groups were administrated with corresponding drugs by gavage, and the control group and the model group with the same volume of 0.5% CMC-Na solution once a day. During the treatment period, the swelling degree of the hind paw was measured and the arthritis was scored until day 30. At the end of drug administration, the pathological changes of the joint tissue were observed by hematoxylin-eosin staining. The content of malondialdehyde(MDA), glutathione(GSH), and Fe~(2+) and the activity of superoxide dismutase(SOD) in the joint tissue were measured by biochemical colorimetry. RT-PCR was performed to determine the mRNA levels of nuclear factor erythroid 2-related factor 2(Nrf2), glutathione peroxidase 4(GPX4), and acyl-CoA synthetase long chain family member 4(ACSL4) in the joint tissue. Western blot was employed to determine the protein levels of Nrf2, Kelch-like ECH-associated protein 1(Keap1), heme oxygenase-1(HO-1), NAD(P)H quinone oxidoreductase 1(NQO1), SOD2, GPX4, and ACSL4 in the joint tissue. The results showed that the treatment with Tripterygium glycosides(7.5 mg·kg~(-1)) and total triterpenes of Euphorbium(32, 64, and 128 mg·kg~(-1)) alleviated the swelling degree of bilateral hind limbs, decreased the arthritis score, reduced joint tissue lesions and the content of MDA and Fe~(2+) in the joint tissue, and increased GSH content and SOD activity. Furthermore, the interventions up-regulated the protein and mRNA levels of Nrf2 and GPX4, down-regulated the protein and mRNA levels of ACSL4, and up-regulated the protein levels of Keap1, NQO1, HO-1, and SOD2 in the Nrf2/HO-1/GPX4. In summary, the total triterpenes of Euphorbium can treat RA by inhibiting lipid peroxidation and abnormal ferroptosis, which may involve the Nrf2/HO-1/GPX4 signaling pathway.
Rats ; Male ; Animals ; Rats, Sprague-Dawley ; NF-E2-Related Factor 2/metabolism* ; Kelch-Like ECH-Associated Protein 1/metabolism* ; Triterpenes/pharmacology* ; Oxidative Stress ; Arthritis, Rheumatoid/genetics* ; Glutathione ; Superoxide Dismutase/metabolism* ; Glycosides/pharmacology* ; RNA, Messenger/metabolism*

Objective:To explore the association between the G71R polymorphism of the UGT1A1 gene and neonatal hyperbilirubinemia. Methods:DNA was extracted from blood samples of 61 neonates with severe neonatal hyperbilirubinemia(severe neonatal hyperbilirubinemia group), 60 neonates with hyperbilirubinemia(hyperbilirubinemia group) and 62 healthy neonates(control group), the G71R mutation of UGT1A1 gene was analyzed by direct sequencing. Results:In severe neonatal hyperbilirubinemia group, there were 17 cases of homozygous mutation(A/A), 23 cases of heterozygous mutation(A/G) , and 21 cases of wild type(G/G) , with 28.87% homozygous mutation rate and 37.70% heterozygous mutation rate.In neonatal hyperbilirubinemia group, there were ten cases of homozygous mutation(A/A), 28 cases of heterozygous mutation(A/G) and 22 cases of wild type(G/G), with 16.67% homozygous mutation rate and 46.67% heterozygous mutation rate.In the control group, there were nine cases of homozygous mutation (A/A), 28 cases of heterozygous mutation(A/G) and 25 cases of wild type(G/G), among which the homozygous mutation rate was 14.52% and the heterozygous mutation rate was 45.16%.The genotype frequency( χ2=4.14, P=0.38)and allele frequency( χ2=2.47, P=0.29)of G71R in severe neonatal hyperbilirubinemia group, neonatal hyperbilirubinemia group and control group were not statistically significant. Conclusion:The G71R polymorphism of the UGT1A1 gene may not be significantly correlated with the prevalence of neonatal hyperbilirubinemia.

Objective:To observe the changes of serum C-terminal peptide of type Ⅰ collagen (CTX-1) and N-terminal lengthening peptide of type Ⅰ collagen (P1NP) in adult patients with skeletal fluorosis in the tea-drinking-borne endemic fluorosis area in Qinghai Province, and to find sensitive indicators for diagnosis of skeletal fluorosis.Methods:From April to August 2019, a case-control study was carried out in tea-drinking-borne endemic fluorosis area in Zhiduo County, Yushu Tibetan Autonomous Prefecture, and Gangcha County, Haibei Tibetan Autonomous Prefecture of Qinghai Province. According to the Diagnostic Standard for Endemic Skeletal Fluorosis (WS/T 192-2008), the clinical diagnosis and X-ray examination of skeletal fluorosis were carried out for permanent residents ≥25 years old and living for more than 10 years in the area, combined with face-to-face inquiry and investigation of past disease history, lifestyle and clinical manifestations. The patients with skeletal fluorosis and healthy people were selected as skeletal fluorosis group and control group, respectively. Randomized urine samples and fasting venous blood from the two groups were collected. The content of fluoride in urine was determined by ion selective electrode method, and the contents of CTX-1 and P1NP in serum were determined by enzyme-linked immunosorbent assay (ELISA).Results:A total of 127 people in the disease area were investigated, including 63 cases in skeletal fluorosis group and 64 cases in control group. There was no statistically significant difference in age and sex ratio between the two groups ( t = 0.42, χ 2 = 0.07, P > 0.05). The X-ray examination results showed that the patients with skeletal fluorosis were mainly mild, accounting for 71.43% (45/63); X-ray changes were mainly ossification of interosseous membrane and tendon. The urinary fluoride in control group and skeletal fluorosis group was 1.62 (1.12, 1.95) and 3.22 (2.38, 4.89) mg/L, respectively, with statistically significant difference between the two groups ( Z = 7.07, P < 0.001). The difference of serum CTX-1 and P1NP contents between the two groups was statistically significant ( Z = 2.00, 4.89, P < 0.05). Conclusions:The levels of serum CTX-1 and P1NP in patients with skeletal fluorosis are higher than those in healthy people. Serum CTX-1 and P1NP may be used as sensitive indicators for diagnosis of skeletal fluorosis.