OBJECTIVE: To identify early potential risk factors for hospital-acquired pneumonia (HAP) in patients with mild traumatic brain injury (mTBI), construct a risk prediction model, and evaluate its predictive efficacy. METHODS: A case-control study was conducted using clinical data from mTBI patients admitted to the neurosurgery department of Changzhou Second People's Hospital from September 2021 to September 2023. The patients were divided into two groups based on whether they developed HAP. Clinical data within 48 hours of admission were statistically analyzed to identify factors influencing HAP occurrence through univariate analysis. Least absolute shrinkage and selection operator (LASSO) regression analysis was employed for feature selection to identify the most influential variables. The dataset was divided into training and validation sets in a 7:3 ratio. A multivariate Logistic regression analysis was then performed using the training set to construct the prediction model, exploring the risk factors for HAP in mTBI patients and conducting internal validation in the validation set. Receiver operator characteristic curve (ROC curve), decision curve analysis (DCA), and calibration curve were utilized to assess the sensitivity, specificity, decision value, and predictive accuracy of the prediction model. RESULTS: A total of 677 mTBI patients were included, with 257 in the HAP group and 420 in the non-HAP group. The significant differences were found between the two groups in terms of age, maximum body temperature (MaxT), maximum heart rate (MaxHR), maximum systolic blood pressure (MaxSBP), minimum systolic blood pressure (MinSBP), maximum respiratory rate (MaxRR), cause of injury, and laboratory indicators [C-reactive protein (CRP), procalcitonin (PCT), neutrophil count (NEUT), erythrocyte sedimentation rate (ESR), fibrinogen (FBG), fibrinogen equivalent units (FEU), prothrombin time (PT), activated partial thromboplastin time (APTT), total cholesterol (TC), lactate dehydrogenase (LDH), prealbumin (PAB), albumin (Alb), blood urea nitrogen (BUN), serum creatinine (SCr), hematocrit (HCT), hemoglobin (Hb), platelet count (PLT), glucose (Glu), K⁺, Na⁺], suggesting they could be potential risk factors for HAP in mTBI patients. After LASSO regression analysis, the key risk factors were enrolled in the multivariate Logistic regression analysis. The results revealed that the cause of injury being a traffic accident [odds ratio (OR) = 2.199, 95% confidence interval (95%CI) was 1.124-4.398, P = 0.023], NEUT (OR = 1.330, 95%CI was 1.214-1.469, P < 0.001), ESR (OR = 1.053, 95%CI was 1.019-1.090, P = 0.003), FBG (OR = 0.272, 95%CI was 0.158-0.445, P < 0.001), PT (OR = 0.253, 95%CI was 0.144-0.422, P < 0.001), APTT (OR = 0.689, 95%CI was 0.578-0.811, P < 0.001), Alb (OR = 0.734, 95%CI was 0.654-0.815, P < 0.001), BUN (OR = 0.720, 95%CI was 0.547-0.934, P = 0.016), and Na⁺ (OR = 0.756, 95%CI was 0.670-0.843, P < 0.001) could serve as main risk factors for constructing the prediction model. Calibration curves demonstrated good calibration of the prediction model in both training and validation sets with no evident over fitting. ROC curve analysis showed that the area under the ROC curve (AUC) of the prediction model in the training set was 0.943 (95%CI was 0.921-0.965, P < 0.001), with a sensitivity of 83.6% and a specificity of 91.5%. In the validation set, the AUC was 0.917 (95%CI was 0.878-0.957, P < 0.001), with a sensitivity of 90.1% and a specificity of 85.0%. DCA indicated that the prediction model had a high net benefit, suggesting practical clinical applicability. CONCLUSIONS The cause of injury being a traffic accident, NEUT, ESR, FBG, PT, APTT, Alb, BUN, and Na⁺ are identified as major risk factors influencing the occurrence of HAP in mTBI patients. The prediction model constructed using these parameters effectively assesses the likelihood of HAP in mTBI patients.
Humans ; Risk Factors ; Case-Control Studies ; Logistic Models ; Healthcare-Associated Pneumonia/epidemiology* ; Brain Injuries, Traumatic/complications* ; Male ; Female ; ROC Curve ; Pneumonia/etiology* ; Middle Aged ; Adult

Small urban wetlands are widely distributed and susceptible to human activities, serving as important sources and sinks of carbon. Microorganisms play a crucial role in carbon cycle, while limited studies have been conducted on the microbial diversity in small urban wetlands and the functions of microbiome in carbon fixation and metabolism. To probe into the microbiome-driven carbon cycling in small urban wetlands and dissect the composition and functional groups of microbiome, we analyzed the relationships between the microbiome structure, element metabolism pathways, and habitat physicochemical properties in sediment samples across three small wetlands in Huzhou City, and compared them with natural wetlands in the Zoige wetland. High-throughput sequencing of 16S rRNA gene amplicons and metagenomics was employed to determine the species and functional groups. Sixty medium to high-quality metagenome-assembled genomes (MAGs) were constructed, including 55 bacterial and 5 archaeal taxa, and their potential in driving elemental cycles were analyzed, with a focus on carbon fixation. Several bacterial species were found to encode a nearly complete carbon fixation pathway, including the Calvin cycle, the reductive tricarboxylic acid cycle, the Wood-Ljungdahl pathway, and the reductive glycine pathway. There were several potential novel carbon-fixing bacterial members, such as those belonging to Syntrophorhabdus (Desulfobacterota) and UBA4417 (Bacteroidetes), which had high relative abundance in the wetland microbiome. Unveiling the genetic potential of these functional groups to facilitate element cycling is of great scientific importance for enhancing the carbon sequestration capacity of small urban wetlands.
Wetlands ; Microbiota/genetics* ; Carbon Cycle/genetics* ; Bacteria/classification* ; RNA, Ribosomal, 16S/genetics* ; China ; Cities ; Geologic Sediments/microbiology* ; Archaea/classification* ; Metagenomics ; Metagenome

BACKGROUND:Short-term wearing of cervical brace combined with shoulder and neck muscle exercise can significantly improve the symptoms of early cervical spondylosis.After stopping wearing cervical brace,patients'symptoms are easy to recur,which may be due to the lack of cervical curvature correction function. OBJECTIVE:To analyze the effect of 3D printed personalized cervical orthopedic brace for adjusting cervical curvature in the treatment of early cervical spondylosis. METHODS:From January 2021 to January 2023,30 patients with early cervical spondylosis in the Shanghai Fifth People's Hospital,Fudan University were studied,including 11 males and 19 females,with a mean age of(31.7±6.6)years old.All patients customized and wore 3D printed personalized cervical orthopedic braces for 3 hours a day for continuous 12 weeks.Borden value of cervical curvature,pain threshold of shoulder and neck muscles,cervical dysfunction index,and visual analog scale score in 30 patients were recorded before and 4 and 8 weeks after treatment. RESULTS AND CONCLUSION:(1)Compared with before treatment,the difference of Borden value of cervical curvature,right trapezius tenderness threshold,and cervical dysfunction index was not significant in 30 patients after 4 weeks of treatment(P>0.05).Visual analog scale score,left trapezius tenderness threshold,left and right C5C6 tenderness threshold were significantly improved(P<0.05).(2)Compared with before treatment,the cervical curvature Borden value,left and right trapezius tenderness threshold,visual analog scale score,left and right C5C6 tenderness threshold,and cervical dysfunction index of 30 patients were significantly improved after 12 weeks of treatment(P<0.05).(3)Compared with 4 weeks after treatment,the Borden value of cervical curvature,right trapezius tenderness threshold,visual analog scale score,left and right C5C6 tenderness threshold and cervical dysfunction index of 30 patients after 12 weeks of treatment were significantly improved(P<0.05).(4)The results show that short-term wearing of 3D printed personalized cervical orthopedic brace can improve the pain of patients with early cervical spondylosis,while long-term application has certain effect on the recovery of cervical curvature.

Science and technological advancements drive human progress, with laboratory animals serving as essential resources for developments in life sciences and medicine. However, the waste generated by these animals presents new challenges for urban management. Issues such as classification, recycling, effective utilization, and biohazard elimination must be addressed, necessitating the development of regulations, standards, and norms to keep pace with advancements. The construction of quality management system is the foundation and framework for the management of inspection and testing organizations. It should have strong operability and inspectability, enabling continuous improvement of the management level and enhancing the stability of basic management. However, current quality management systems often lack clarity in managing laboratory animal waste, including undefined disposal processes for non-medical institutions, inaccurate waste classification, and inadequate disposal methods for different waste categories. This paper addresses these challenges by identifying necessary processes to be added or removed in the quality management system of National Institutes for Food and Drug Control, developing effective SOPs, proposing practical measures to strengthen supervision and management, and integrating 6S management principles into our quality management system. In conclusion, effective management of laboratory animal waste should be centered on improving the quality management system, emphasizing waste classification and management at the source, controlling biological hazards, minimizing environmental pollution and promoting conditions for sustainable development.

Objective To observe the clinical efficacy of Shen Shuai Ⅱ Granules combined with integrated Western medicine therapy in patients with primary chronic kidney disease(CKD)in stages 3-4 with the syndrome of spleen and kidney qi deficiency,dampness turbidity and blood stasis,and its effects on expression of serum autophagy related proteins.Methods Totally 88 patients were randomly divided into treatment group and control group,with 44 cases in each group.Both groups were given an integrated Western medicine therapy.On this basis,the treatment group was given Shen Shuai Ⅱ Granules,while the control group was given Shen Shuai Ⅱ placebo,1 bag at a time,twice a day,orally.The treatment for both groups lasted for 24 weeks.The clinical efficacy of the two groups was observed.The TCM symptom scores,serum creatinine(Scr),blood urea nitrogen(BUN),uric acid(UA),blood calcium(Ca2+),blood phosphorus(P3-),parathyroid hormone(PTH),and 24-hour urinary protein quantification(24 UPro)before and after treatment were compared in the two groups.The serum levels of autophagy related protein Beclin-1,Atg7,and LC3-Ⅱ were detected by ELISA before and after treatment in the two groups.Safety indexes of both groups were monitored.Results During the treatment,4 cases fell off in the treatment group and 4 cases in the control group.The total effective rate in the treatment group was 55％(22/40),while that in the control group was 30％(12/40).The therapeutic effect in the treatment group was better than that in the control group(P<0.01).Compared with before treatment,the TCM symptom scores in the treatment group decreased after treatment(P<0.01),the levels of Scr,BUN,UA,P3-,PTH,and 24 UPro decreased(P<0.05,P<0.01),while eGFR increased(P<0.01).The levels of Scr in the control group increased(P<0.05),while eGFR decreased(P<0.01).After treatment,the treatment group had lower various TCM symptom scores,Scr,BUN,UA,P3-,PTH,and 24 UPro levels than the control group(P<0.01,P<0.05),and higher eGFR than the control group(P<0.01).Compared with before treatment,the serum levels of Beclin-1,Atg7,and LC3-Ⅱ increased in the treatment group after treatment(P<0.01,P<0.05),while the serum level of Beclin-1 decreased in the control group after treatment(P<0.01).After treatment,the improvement of the above indicators in the treatment group were better than those in the control group(P<0.01,P<0.05).Correlation analysis showed that Beclin-1,Atg7,and LC3-Ⅱ were negatively correlated with Scr and BUN(P<0.05),and positively correlated with eGFR(P<0.05).There was no obvious adverse reaction in both groups.Conclusion The combination of Shen Shuai Ⅱ Granules and integrated Western medicine therapy for the treatment of primary CKD in stages 3-4 with the syndrome of spleen and kidney qi deficiency,dampness turbidity and blood stasis has confirmed efficacy,which can effectively alleviate clinical symptoms,improve renal function,and delay the progression of CKD.The mechanism may be related to improving the level of autophagy in renal.

Objective:To investigate the risk factors that affected pathological diagnosis upgrading after resection of colorectal adenoma.Methods:From January 2017 to December 2022, a total of 1 059 patients who underwent adenoma resection after pathologically diagnosed as adenoma by endoscopic forceps biopsy(EFB)were included in General Hospital of Ningxia Medical University. The patients were divided into the pathologically no difference group (1 003 cases) and the pathologically upgraded group (56 cases) based on the comparison of pathological diagnosis of EFB specimens and the specimens after adenoma resection. Clinical information and endoscopic characteristics of the adenoma were compared between the 2 groups. The clinical information included smoking history, family history of colorectal cancer, and the endoscopic characteristics included maximum diameter, morphological characteristics, surface depression, erosion or ulceration, and surface color of adenoma. Chi-square test and Fisher′s exact test were used for statistical analysis. Multivariate logistic regression model was used to analyze the risk factors for pathological diagnosis upgrading after adenoma resection.Results:The proportions of patients with smoking history, family history of colorectal cancer, concomitant hypertension, and coronary heart disease in the pathologically upgraded group were higher than those in the pathologically no difference group (46.43%, 26/56 vs.26.12%, 262/1 003; 8.93%, 5/56 vs.0.70%, 7/1 003; 46.43%, 26/56 vs.30.11%, 302/1 003; 21.43%, 12/56 vs.9.27%, 93/1 003), and the differences were statistically significant( χ2=11.05, Fisher′s exact test, χ2=6.61 and 8.78; all P<0.05). There were statistically significant differences between the pathologically no difference group and pathologically upgraded group in the maximum diameter (929 cases (92.62%) and 23 cases (41.07%) of < 20 mm, and 74 cases (7.38%) and 33 cases (58.93%) of ≥20 mm, respectively), morphological characteristics (220 cases (21.93%) and 28 cases (50.00%) with pedicle, and 783 cases (78.07%) and 28 cases (50.00%) without pedicle, respectively), surface color (347 cases (34.60%) and 3 cases (5.36%) of near normal mucosa, 613 cases (61.12%) and 50 cases (89.29%) of red surface color, and 43 cases (4.29%) and 3 cases (5.36%) of white surface color, respectively), erosion or ulceration (78 cases (7.78%) and 36 cases (64.29%) had erosion or ulceration, and 925 cases (92.22%) and 20 cases (35.71%) had no erosion or ulceration, respectively), and surface depression (6 cases (0.60%) and 8 cases (14.29%) of depression, and 997 cases (99.40%) and 48 cases (85.71%) of non depression, respectively) ( χ2=155.18, 23.30, 20.58 and 176.31, Fisher′s exact test; all P<0.001). The result of multivariate logistic regression analysis showed that surface depression ( OR=25.198, 95% confidence interval (95% CI) 5.812 to 109.246, P<0.001), erosion or ulceration( OR=9.913, 95% CI 4.652 to 21.124, P<0.001), red surface color ( OR=4.276, 95% CI 1.053 to 17.363, P=0.042), white surface color ( OR=8.803, 95% CI 1.398 to 55.435, P=0.021), maximum diameter≥20 mm ( OR=4.689, 95% CI 2.265 to 9.706, P<0.001), family history of colorectal cancer ( OR=8.764, 95% CI 1.418 to 54.162, P=0.019) and smoking history ( OR=2.713, 95% CI 1.376 to 5.349, P=0.004) were independent risk factors for pathological diagnosis upgrading after adenoma resection. Conclusion:Surface depression, maximum diameter ≥20 mm, erosion or ulceration, white or red surface color, family history of colorectal cancer and smoking history may enhance the heterogeneity of adenomas, interfere with the accuracy of EFB pathology, and lead to an upgrade of pathological diagnosis after adenoma resection.

Objective:To compare the clinical effective of clavicular hook plate with extra suture hole and traditional hook plate in the treatment of acute acromioclavicular dislocation.Methods:This study retrospectively analyzed the clinical data of traumatic acromioclavicular dislocation patients who were treated by operation from March 2017 to September 2020. The patients were included in traditional hook plate (THP) group and triangle stabilization technique hook plate (TSTHP) group according fracture fixations. TSTHP group adopted clavicular hook plate with extra suture hole. There were 27 patients in THP group with 18 male patients and 9 female patients; average age with 37.56±8.94 years old; 16 patients injured left side and 11 patients injured right side; crush injuries of 10 patients, traffic injuries of 9 patients and sports injuries of 8 patients; Rockwood classification of type III (9 patients), type IV (10 patients) and type V (8 patients). There were 20 patients in TSTHP group with 15 male patients and 5 female patients; average age with 38.95±9.91 years old; 13 patients injured left side and 7 patients injured right side; crush injuries of 9 patients, traffic injuries of 8 patients and sports injuries of 3 patients; Rockwood classification of type III (5 patients), type IV (9 patients) and type V (6 patients). The operation time, intraoperative bleeding, postoperative coracoclavicular space, visual analogue scale (VAS) and shoulder joint Constant-Murley score were compared between the two groups.Results:The operation time and blood loss of THP group and TSTHP group were 51.07±11.27 min, 87.41±15.34 ml and 55.65±8.59 min, 90.50±14.32 ml, respectively. The difference was not statistically significant ( t=1.52, 0.70, all P>0.05). Patients in both groups were followed up for 12 to 14 months after operations, with an average of 12.28 months. Six months after surgery, the coracoclavicular spaces of THP group and TSTHP group were 12.16±0.90 mm and 11.26±0.70 mm, respectively. The difference was statistically significant ( t=3.70, P<0.001). Postoperative VAS scores (2 days, 3 months, 6 months and 12 months) of TSTHP group [1.8±0.77, 0.00(0.00, 1.00), 0.00 (0.00, 0.00), 0.00(0.00, 0.00)] were significantly better than THP group [4.22±1.25, 2.00 (1.00, 3.00), 1.00 (0.00, 1.00), 0.00 (0.00, 1.00)]. The difference was statistically significant ( t=7.65, P<0.001; Z=4.85, P<0.001; Z=3.44, P=0.001; Z=2.96, P=0.003). Postoperative Constant-Murley scores (3 months, 6 months and 12 months) of TSTHP group (87.00±5.18, 91.25±2.75, 92.30±2.74) were significantly better than THP group (76.96±5.21, 83.22±3.86, 85.22±3.49). The difference was statistically significant ( t=6.54, 7.93, 7.51; P<0.001). The postoperative complication rates of THP group were higher than TSTHP group [70.4% (19/27) vs. 5.0% (1/20)]. Conclusion:In the treatment of acute acromioclavicular dislocation, the clavicular hook plate with extra suture hole can obtain satisfactory clinical effect compared with the THP, and clavicular hook plate with extra suture hole is more conducive to early recovery of shoulder function and reduce postoperative complications.

Objective:To investigate the clinical efficacy of early pancreatic duct stenting in the treatment of acute pancreatitis.Methods:The retrospective and descriptive study was conducted. The clinical data of 201 patients with acute pancreatitis who were admitted to General Hospital of Ningxia Medical University from October 2011 to December 2017 were collected. There were 106 males and 95 females, aged from 18 to 90 years, with a median age of 62 years. Of 201 patients, there were 178 cases with moderate severe acute pancreatitis and 23 cases with serious severe acute pancreatitis. Patients were treated with pancreatic duct stenting within 48 hours after admission. Observation indicators: (1) treatment; (2) follow-up. Follow-up was conducted using outpatient examination and telephone interview to detect recurrence of acute pancreatitis after surgery up to June 2019. Measurement data with normal distribution were represented by Mean± SD, and the independent sample t test was used for comparison between groups, and the matched samples t test was used for comparison between before and after. Measurement data with skewed distribution were represented by M( P25 ,P75) or M(range), and the Mann-Whitney U test was used for comparison between groups, and the Wilcoxon signed rank sum test was used for comparison between before and after. Count data were expressed as absolute numbers or percentages, and comparison between groups was analyzed using the chi-square test . Results:(1) Treatment: 201 patients received pancreatic duct stenting successfully, 63 of which were detected pancreatic obstruction with white-floc. The interval time from admission to surgery , operation time, time for initial oral intake, duration of hospital stay and hospital expenses of 201 patients were 10 hours(4 hours,22 hours), (35±15)minutes, 3 days(2 days,5 days), 6 days(5 days,10 days) and 3.8×10 4 yuan (3.0×10 4 yuan,4.9×10 4 yuan). Of 201 patients, 22 patients were transferred to intensive care unit, including 1 case with serious severe underwent inhospital death and 1 case with moderate severe and 7 cases with serious severe underwent auto-discharge from hospital. There were 25 cases with local complications, including 17 cases with pancreatic infectious necrosis, 7 cases with pancreatic walled-off necrosis and 1 case with spleen infarction. All 25 patients were cured after surgical inter-vention or conservative treatment. Further analysis showed that cases being transferred to intensive care unit, cases undergoing surgical treatment, the time for initial oral intake, duration of hospital stay and cases undergoing auto-discharge from hospital were 6, 11, 3 days(2 days,5 days), 6 days(5 days,10 days) and 1 for the 178 moderate severe cases, versus 16, 5, 7 days(4 days,9 days), 9 days (7 days,17 days) and 7 for the 23 serious severe cases, showing significant differences ( χ2=91.561, 6.730, Z=6.485, 5.463, χ2=47.561, P<0.05). The white blood cell count, serum amylase indexes and chronic health evaluation Ⅱ score of 201 patients were (14±6)×10 9/L, 928 U/L(411 U/L,1 588 U/L), 9±5 before admission, versus (10±4)×10 9/L, 132 U/L(72 U/L,275 U/L), 6±4 at 48 hours after admission, respectively, showing significant differences ( t=12.219, Z=11.639, t=16.016, P<0.05). (2) Follow-up: of 201 patients, 153 cases were followed up for 40 months (27 months,55 months). During the follow-up, 32 of the 153 cases had recurrence of acute pancreatitis. Conclusion:Early pancreatic duct stenting is safe and feasible in the treatment of acute pancreatitis.

Objective: To explore the predictor of lower airway inflammation among the index of nasal inflammation by investigating the expression and association of eosinophils (EOS) in the upper-lower airways and blood of patients with chronic rhinitis. Methods: A total of 162 patients with allergic rhinitis (AR), 117 patients with non-allergic rhinitis (NAR) and 104 controls were enrolled from June 2010 to December 2013 from General Hospital of Eastern Theater Command, People′s Liberation Army. All subjects were required detailed medical history collection and nasal resistance measurement. Skin prick test (SPT), blood total immunoglobin E (tIgE) and blood EOS, nasal lavage and induced sputum EOS, nasal provocation and bronchial provocation test (NPT, BPT), nasal and forced exhaled nitric oxide (NNO, FeNO) were performed in all patients. One-way analysis of variance was used for comparison between groups. LSD t test or Mann-Whitney U test was used for comparison between the two groups. Pearson or Spearman related parameter test was used for correlation analysis. Results: The nasal lavage EOS, NNO, induced sputum EOS, FeNO, blood EOS and tIgE were higher in the AR group than that in the NAR group (3.70[1.20, 14.23]/200 HP vs 1.40[0.20, 3.40]/200 HP, 673.50[466.80, 936.00] ppb vs 455.80[248.10, 705.60] ppb, 2.97[0.00, 10.63]% vs 1.00[0.23, 2.00]%, (49.28±26.37)ppb vs (34.07±19.11)ppb, 4.00[2.00, 7.00]% vs 2.00[1.00, 5.00]%, 208.01[61.70, 387.50] IU/ml vs 43.30[19.00, 122.00] IU/ml, F or χ² value was 11.442, 19.440, 70.727, 69.449, 47.453, 46.525, respectively, all P<0.05). But there was no significant difference in nasal resistance, NPT and BPT between the two groups. Nasal lavage EOS in AR group and NAR group was correlated with induced sputum EOS, FeNO, tIgE and blood EOS (r value of AR group was 0.448, 0.202, 0.159, 0.321, r value of NAR group was 0.442, 0.268, 0.268, 0.334, respectively, all P<0.05), but not with BPT. After adjustment for gender, age, height and weight, nasal EOS was positively correlated with sputum EOS. Multiple linear regression analysis showed that nasal EOS, blood EOS and SPT were factors affecting sputum EOS levels. The optimal threshold for nasal EOS to determine induced sputum EOS was 3.30/200 HP by (receiver operating characteristic,ROC) analysis. Conclusion The nasal EOS is correlated with multiple lower airway and systemic inflammatory markers, and is a risk factor for the induced sputum EOS, which can be used as an inflammation biomarker to predict the lower air inflammation.

Objective To study the mechanism of central nervous system (CNS) injury in chronic fluorosis and the neuroprotective effect of chondroitin sulfate (CS).Methods Forty-eight female Sprague-Dawley rats weighting 90-120 g were divided into 8 groups according to body weight by random number table,6 rats in each group:control group,drinking tap water freely;low dose and high dose fluoride groups,freely drinking tap water with fluoride content of 10 and 50 mg/L,respectively;control + normal saline (NS),low dose fluoride + NS,and high dose fluoride + NS groups,each group was fed for 180 d,and treated with intraperitoneal injection of 0.66 mg/kg NS for 5 d (once a day);low dose fluoride + CS and high dose fluoride + CS groups,each group was fed for 180 d,0.66 mg/kg CS was injected intraperitoneally for 5 d (once a day).All groups were fed standard nutritive animal feed for 185 d and dissected for brain tissue.The pathologic change was observed after hematoxylin-eosin (HE)staining;the expression levels of phosphorylated extracellular signal-regulated protein kinase 1/2 (phospho-Erk1/2)and glutamate receptors 1,2 (GluR1,GluR2) in the brain cortex were detected by immunohistochemistry;the protein levels of Erk1/2,phospho-Erk1/2,GluR1,and GluR2 in the brain cortex were detected by Western blotting.Results Brain cortex of all rats in the fluoride groups showed eosinophilic degeneration,loss and disordered arrangement of neurons,and the brain morphological changes in each fluoride + CS groups were significantly improved compared with those in the fluoride groups.Immunohistochemistry results showed that compared with the control group [(0.44 ± 0.09)％,(1.49 ± 0.05)％,(2.51 ± 0.54)％],the expression levels of phospho-Erk1/2 [(1.47 ±0.09)％,(1.03 ± 0.05)％],and GluR2 [(2.37 ± 0.06)％,(3.38 ± 0.12)％] in the low dose and high dose fluoride groups were increased,and the expression levels of GluR1 [(1.49 ± 0.02)％,(0.99 ± 0.19)％] were decreased (P ＜ 0.05).Western blotting results showed that compared with the control group (1.00 ± 0.12,1.76 ± 0.33),the protein levels of Erk1/2 (3.10 ± 0.76,1.99 ± 0.01) and phospho-Erk1/2 (3.27 ± 0.25,2.67 ± 0.05) in low dose and high dose fluoride groups were significantly increased (P ＜ 0.05);compared with low dose fluoride group,the protein levels of Erk1/2,and phospho-Erk1/2 (1.30 ± 0.31,2.20 ± 0.34) in low dose fluoride + CS group decreased significantly (P ＜0.05).Compared with control group (1.86 ± 0.47,1.17 ± 0.27),the protein levels of GluR1 (1.09 ± 0.26,0.61 ± 0.14) in low dose and high dose fluoride groups decreased significantly,while the protein level of GluR2 (1.99 ± 0.42,3.38 ±0.27) increased significantly (P ＜ 0.05);compared with low dose and high dose fluoride groups,the protein levels of GluR2 in low dose fluoride + CS and high dose fluoride + CS groups (1.53 ± 0.41,2.65 ± 0.32) decreased significantly (P ＜ 0.05).The protein level of phospho-Erk1/2 was negatively correlated with GluR1 protein level (r =-0.975,-0.991,P ＜ 0.05) in low dose and high dose fluoride groups,and it was positively correlated with the protein level of GluR2 (r =0.986,0.993,P ＜ 0.05).Conclusion The CNS injury caused by chronic fluorosis may be related to GluR1 and GluR2 activated Erk1/2 signaling pathway,and CS has certain protection to the injury.