Alzheimer’s disease (AD) is a prevalent neurodegenerative condition characterized by progressive cognitive decline and memory loss. As the incidence of AD continues to rise annually, researchers have shown keen interest in the active components found in natural plants and their neuroprotective effects against AD. Quercetin, a flavonol widely present in fruits and vegetables, has multiple biological effects including anticancer, anti-inflammatory, and antioxidant. Oxidative stress plays a central role in the pathogenesis of AD, and the antioxidant properties of quercetin are essential for its neuroprotective function. Quercetin can modulate multiple signaling pathways related to AD, such as Nrf2-ARE, JNK, p38 MAPK, PON2, PI3K/Akt, and PKC, all of which are closely related to oxidative stress. Furthermore, quercetin is capable of inhibiting the aggregation of β‑amyloid protein (Aβ) and the phosphorylation of tau protein, as well as the activity of β‑secretase 1 and acetylcholinesterase, thus slowing down the progression of the disease.The review also provides insights into the pharmacokinetic properties of quercetin, including its absorption, metabolism, and excretion, as well as its bioavailability challenges and clinical applications. To improve the bioavailability and enhance the targeting of quercetin, the potential of quercetin nanomedicine delivery systems in the treatment of AD is also discussed. In summary, the multifaceted mechanisms of quercetin against AD provide a new perspective for drug development. However, translating these findings into clinical practice requires overcoming current limitations and ongoing research. In this way, its therapeutic potential in the treatment of AD can be fully utilized.

ObjectiveTo investigate the role of 4-week high-intensity interval training (HIIT) in modulating the metabolic homeostasis of the pyruvate-lactate axis in the hippocampus of rats with chronic unpredictable mild stress (CUMS) to improve their depressive-like behavior. MethodsForty-eight SPF-grade 8-week-old male SD rats were randomly divided into 4 groups: the normal quiet group (C), the CUMS quiet group (M), the normal exercise group (HC), and the CUMS exercise group (HM). The M and HM groups received 8 weeks of CUMS modeling, while the HC and HM groups were exposed to 4 weeks of HIIT starting from the 5th week (3 min (85%-90%) S_max+1 min (50%-55%) S_max, 3-5 cycles, S_max is the maximum movement speed). A lactate analyzer was used to detect the blood lactate concentration in the quiet state of rats in the HC and HM groups at week 4 and in the 0, 2, 4, 8, 12, and 24 h after exercise, as well as in the quiet state of rats in each group at week 8. Behavioral indexes such as sucrose preference rate, number of times of uprightness and number of traversing frames in the absenteeism experiment, and other behavioral indexes were used to assess the depressive-like behavior of the rats at week 4 and week 8. The rats were anesthetized on the next day after the behavioral test in week 8, and hippocampal tissues were taken for assay. LC-MS non-targeted metabolomics, target quantification, ELISA and Western blot were used to detect the changes in metabolite content, lactate and pyruvate concentration, the content of key metabolic enzymes in the pyruvate-lactate axis, and the protein expression levels of monocarboxylate transporters (MCTs). Results4-week HIIT intervention significantly increased the sucrose preference rate, the number of uprights and the number of traversed frames in the absent field experiment in CUMS rats; non-targeted metabolomics assay found that 21 metabolites were significantly changed in group M compared to group C, and 14 and 11 differential metabolites were significantly dialed back in the HC and HM groups, respectively, after the 4-week HIIT intervention; the quantitative results of the targeting showed that, compared to group C, lactate concentration in the hippocampal tissues of M group, compared with group C, lactate concentration in hippocampal tissue was significantly reduced and pyruvate concentration was significantly increased, and 4-week HIIT intervention significantly increased the concentration of lactate and pyruvate in hippocampal tissue of HM group; the trend of changes in blood lactate concentration was consistent with the change in lactate concentration in hippocampal tissue; compared with group C, the LDHB content of group M was significantly increased, the content of PKM2 and PDH, as well as the protein expression level of MCT2 and MCT4 were significantly reduced. The 4-week HIIT intervention upregulated the PKM2 and PDH content as well as the protein expression levels of MCT2 and MCT4 in the HM group. ConclusionThe 4-week HIIT intervention upregulated blood lactate concentration and PKM2 and PDH metabolizing enzymes in hippocampal tissues of CUMS rats, and upregulated the expression of MCT2 and MCT4 transport carrier proteins to promote central lactate uptake and utilization, which regulated metabolic homeostasis of the pyruvate-lactate axis and improved depressive-like behaviors.

ObjectiveThis study aimed to investigate the effects of 4-week high-intensity interval training (HIIT) on synaptic plasticity in the prefrontal cortex (PFC) of rats exposed to chronic unpredictable mild stress (CUMS), and to explore its potential mechanisms. MethodsA total of 48 male Sprague-Dawley rats were randomly divided into 4 groups: control (C), model (M), control plus HIIT (HC), and model plus HIIT (HM). Rats in groups M and HM underwent 8 weeks of CUMS to establish depression-like behaviors, while groups HC and HM received HIIT intervention beginning from the 5th week for 4 consecutive weeks. The HIIT protocol consisted of repeated intervals of 3 min at high speed (85%-90% maximal training speed, S_max) alternated with one minute at low speed (50%-55% S_max), with 3 to 5 sets per session, conducted 5 d per week. Behavioral assessments and tail-vein blood lactate levels were measured at the end of the 4th and 8th weeks. After the intervention, rat PFC tissues were collected for Golgi staining to analyze synaptic morphology. Enzyme-linked immunosorbent assays (ELISA) were employed to detect brain-derived neurotrophic factor (BDNF), monocarboxylate transporter 1 (MCT1), lactate, and glutamate levels in the PFC, as well as serotonin (5-HT) levels in serum. Additionally, Western blot analysis was conducted to quantify the expression of synaptic plasticity-related proteins, including c-Fos, activity-regulated cytoskeleton-associated protein (Arc), and N-methyl-D-aspartate receptor 1 (NMDAR1). ResultsCompared to the control group (C), the CUMS-exposed rats (group M) exhibited significant reductions in sucrose preference rates, number of grid crossings, frequency of upright postures, and entries into and duration spent in open arms of the elevated plus maze, indicating marked depressive-like behaviors. Additionally, the group M showed significantly reduced dendritic spine density in the PFC, along with elevated levels of c-Fos, Arc, NMDAR1 protein expression, and increased concentrations of lactate and glutamate. Conversely, BDNF and MCT1 contents in the PFC and 5-HT levels in serum were significantly decreased. Following HIIT intervention, rats in the group HM displayed considerable improvement in behavioral indicators compared with the group M, accompanied by significant elevations in PFC MCT1 and lactate concentrations. Furthermore, HIIT notably normalized the expression levels of c-Fos, Arc, NMDAR1, as well as glutamate and BDNF contents in the PFC. Synaptic spine density also exhibited significant recovery. ConclusionFour weeks of HIIT intervention may alleviate depressive-like behaviors in CUMS rats by increasing lactate levels and reducing glutamate concentration in the PFC, thereby downregulating the overexpression of NMDAR, attenuating excitotoxicity, and enhancing synaptic plasticity.

Objective To investigate the relationship between serum stem cell factor receptor(c-kit)and myocardial fibrosis,cardiac function and prognosis in patients with dilated cardiomyopathy(DCM)complicat-ed with heart failure.Methods A total of 77 patients with DCM complicated with heart failure who were trea-ted in 3201 Hospital from May 2020 to June 2022 were enrolled in the study as study group,and 70 DCM pa-tients without heart failure were enrolled as the control group.The levels of serum c-kit mRNA and three my-ocardial fibrosis markers[α-smooth muscle actin(α-SMA),collagen type Ⅰ and collagen type Ⅲ]were detec-ted in the two groups.Cardiac function parameters were obtained by echocardiography.The relationship be-tween serum c-kit mRNA level and myocardial fibrosis and cardiac function was analyzed.According to the oc-currence of major adverse cardiovascular events(MACE),the patients were divided into poor prognosis group and good prognosis group.Multivariate Logistic regression analysis was used to analyze the factors affecting the prognosis of DCM patients complicated with heart failure.Receiver operating characteristic(ROC)curve was used to analyze the efficacy of serum c-kit mRNA level in predicting the prognosis of DCM patients.Results The serum c-kit mRNA level in the study group was lower than that in the control group(P＜0.05).The levels of three myocardial fibrosis indicators in the study group were higher than those in the con-trol group(P＜0.05).The left ventricular ejection fraction(LVEF)in the study group was lower than that in the control group(P＜0.05),and the left ventricular end-diastolic volume(LVEDV)and left ventricular end-systolic volume(LVESV)in the study group were higher than those in the control group(P＜0.05).Pearson correlation analysis showed that serum c-kit mRNA level was positively correlated with LVEF(r=0.677,P＜0.05),while negatively correlated with α-SMA,collagen type Ⅰ,collagen type Ⅲ,LVEDV and LVESV(r=-0.725,-0.748,-0.744,-0.745,-0.662,P＜0.05).Multivariate Logistic regression analysis showed that serum c-kit mRNA level is an independent factor for the prognosis of DCM patients with heart failure.ROC curve analysis showed that serum c-kit mRNA level had a sensitivity of 82.80％,a specificity of 81.80％,and an area under the curve of 0.829(95％CI:0.745-0.912,P＜0.001)for evaluating the progno-sis of DCM patients complicated with heart failure.Conclusion The serum c-kit mRNA level is significantly decreased in patients with DCM complicated with heart failure,and the serum c-kit mRNA level is correlated with myocardial fibrosis and cardiac function.The detection of serum c-kit mRNA level has a high efficacy in evaluating the prognosis of patients with DCM complicated with heart failure.

ObjectiveTo observe the effect of Zuoguiwan on ovarian reserve in the female offspring rat model of prenatal stress （PS） and explore the mechanism based on Toll-like receptor 4/nuclear factor-κB p65 （TLR4/NF-κB p65） signaling pathway. MethodThirty-two pregnant rats were prepared and randomized into four groups （n=8）： control， model， Zuoguiwan （18.9 mg·kg^-1）， and vitamin E （1.44 mg·kg^-1）. Except the control group， the other three groups were subjected to chronic unpredictable mild stress （CUMS） from day 11 of pregnancy， and the modeling was accompanied by gavage with corresponding drugs until delivery. The PS model was evaluated by the sucrose preference test， open field test， and serum corticosterone （CORT） level. The estrous cycle was monitored and the morphological changes in the ovarian tissue were observed. The serum levels of estradiol （E₂）， luteinizing hormone （LH）， follicle-stimulating hormone （FSH）， and anti-Mullerian hormone （AMH） in the 75-day-old offspring rats were measured by enzyme-linked immunosorbent assay （ELISA） to evaluate the ovarian reserve. The ovary and uterus indices were calculated. The serum levels of interleukin-1β （IL-1β） and tumor necrosis factor-α （TNF-α） were measured by enzyme-linked immunosorbent assay （ELISA）. The morphology of the ovarian tissue in the offspring on the day of birth and day 75 after birth was observed by hematoxylin-eosin staining. The transport of NF-κB p65 to the nucleus in the ovaries of the 75-day-old offspring was detected by the immunofluorescence （IF） assay. The expression of TLR4， NF-κB p65 and other related proteins in the ovarian tissue was determined by Western blot. ResultCompared with the control group， the model group showed reduced primordial follicles in the offspring on the day of birth （P<0.01） as well as disturbed estrous cycle， decreased ovary index and uterus index （P<0.01）， reduced corpus luteum， increased atretic follicles （P<0.01）， lowered serum levels of AMH and E₂ （P<0.01）， elevated serum levels of LH， FSH， IL-1β， and TNF-α （P<0.05， P<0.01）， and up-regulated protein levels of TLR4， NF-κB p65， recombinant myeloid differentiation factor 88 （MyD88）， and phosphorylated NF-κB inhibitor （p-IκBα） （P<0.01） in the 75-day-old offspring rats. Compared with the model group， Zuoguiwan and vitamin E increased the primordial follicles in the offspring on the day of birth （P<0.01）. Moreover， they resumed the estrous cycle， increased the ovary and uterine indices （P<0.05， P<0.01） and corpus luteum （P<0.01）， reduced atretic follicles （P<0.01）， elevated the serum levels of AMH and E₂ （P<0.05， P<0.01）， lowered the serum levels of LH， FSH， IL-1β， and TNF-α （P<0.05， P<0.01）， and down-regulated the expression of TLR4， NF-κB p65， MyD88， and p-IκB-α （P<0.05， P<0.01） in the 75-day-old offspring. ConclusionZuoguiwan can improve the ovarian reserve in the offspring rat model of congenital kidney deficiency by regulating the TLR4/NF-κB p65 signaling pathway.

Objective To investigate the effects of total flavones from Oxytropis falcata Bunge on hepatic fibrosis(HF)induced by carbon tetrachloride and liver transforming growth factor(TGF-β)/Smad signaling pathway.Methods Forty-eight male rats were randomly divided into normal group(intraperitoneal injection of peanut oil,intragastric administration of 0.9％NaCl),model group(intraperitoneal injection of 40％CC14 peanut oil solution induced HF model,intragastric administration of 0.9％NaCl),positive control group(modeling,intragastric administration of 0.2 mg·kg-1 of colchicine),experimental-L,-M,-H groups(modeling,intragastric administration of 100,200 and 400 mg·kg-1 of total flavonoid extract of Oxytropis falcata Bunge),8 individuals in each group,for 4 consecutive weeks.The histopathological changes were observed by hematoxylin-eosin and Masson staining.Serum liver function and liver fibrosis were measured;erum inflammatory factors were detected;fluorescence quantitative polymerase chain reaction(RT-qPCR)was used to determine gene expression in liver.Results The pathological injury of liver tissue in the model group was serious,and a large number of inflammatory factors and collagen fibers were accumulated,while the rest of the treatment groups had different degrees of remission.In normal group,model group,positive control group,experimental-L,-M,-H groups,glutamic-pyruvic transaminase levels were(49.28±12.44),(5 885.42±948.37),(4 454.60±489.27),(4 650.47±843.53),(3 761.75±887.30)and(3 544.90±1 066.75)μg·L-1;glutamic-oxaloacetic transaminase levels were(186.90±46.89),(5 936.23±793.81),(3 971.37±780.28),(4 360.30±863.35),(3 943.10±439.47)and(3 971.38±631.08)μg·L-1;hyaluronic acid levels were(45.08±17.16),(104.32±36.06),(66.83±20.09),(70.30±21.07),(60.00±9.68)and(59.02±10.73)μg·L-1;laminin levels were(23.13±3.89),(60.85±13.66),(35.67±9.92),(39.98±9.39),(36.55±12.21)and(34.68±24.83)μg·L-1;type Ⅲ procollagen level were(24.98±5.34),(82.58±30.14),(40.70±16.14),(51.08±23.21),(43.60±12.48)and(44.20±11.66)p±g·L-1;interleukin(IL)-1β levels were(37.63±1.24),(46.10±3.23),(39.22±2.36),(41.33±0.93),(40.25±2.04)and(39.18±2.23)pg·mL-1;tumor necrosis factor-α levels were(314.58±20.56),(383.71±16.97),(349.00±7.93),(348.88±25.11),(325.75±27.84)and(335.07±21.33)pg·mL-1;TGF-β1 mRNA expression of relative quantity respectively were 1.00±0.00,60.99±15.70,9.61±1.59,7.37±1.09,6.41±0.64,6.87±1.09;Smad7 mRNA relative expression were 1.00±0.00,0.34±0.05,0.21±0.03,0.35±0.02,0.38±0.02,0.42±0.03.The above indexes in the model group were compared with the normal group,and the above indexes in the experimental-M,-H groups were compared with the model group,and the differences were statistically significant(P＜0.05,P＜0.01,P＜0.001).Conclusion Total flavonoids of Oxytropis falcata Bunge have protective effects on CC14-induced liver fibrosis in rats,and the mechanism may be related to the regulation of TGF-β/Smad pathway.

Objective: To understand the pubertal development of primary and secondary school students in urban and rural areas of the Inner Mongolia Autonomous Region in 2021, so as to provide clues for further clarification of the health hazards of early pubertal initiation. Methods: From October to November 2021, primary and secondary school students in 12 provinces and cities of Inner Mongolia were selected by stratified cluster random sampling, including 21 662 girls who had reached menarche and 10 600 boys who had their first seminal emission, as well as 46 183 girls who had not reached menarche and 78 995 boys who had not experienced their first seminal emission. The height and weight of the primary and secondary school students were measured, and the time of first seminal emission or menarche was recorded. The study used the Mann-Whitney U test to analyze the differences between urban and rural students, Spearmans rank correlation to analyze the correlation between overweight and obesity and the age of pubertal initiation, and the Logistic regression model to analyze the correlation between pubertal initiation and age of pubertal initiation. Results: The age of menarche for urban girls [(12.31±1.29) years old] was earlier than that of suburban girls [(12.43±1.24) years old], and the age of first spermatozoa for urban boys [(13.85±1.20) years old] was statistically significant compared with that of suburban boys [(13.79±1.36) years old] (t=12.76, 10.58, P<0.05). There was a negative correlation between the age of menarche and overweight/obesity among girls aged 10-14 years (r=-0.169, P<0.05), and there was no statistically significant correlation between the age of spermarche and overweight/obesity in boys aged 5-9, 10-14, and 15-20 years (r=0.122, -0.022, -0.004, P>0.05). The occurrence of menarche in overweight girls was 1.06(95%CI=1.01-1.11) times higher than that in the normal group, and 1.13(95%CI=1.06-1.20) times higher among obese girls than normalweight girls. Compared to urban areas, primary and secondary school students in suburban counties observed the onset of puberty later [OR=0.88(95%CI=0.85-0.91) for menarche, OR=0.94(95%CI=0.89-0.99) for first spermatozoa] (P<0.05). Conclusions Obesity during childhood and adolescence is associated with earlier onset of puberty among female students in Inner Mongolia, and later onset of puberty among primary and secondary school students in suburban counties compared with those in urban areas.

Objective:To investigate the clinical effect of jujube core-shaped tissue resection technique in the treatment of alar reduction.Methods:A retrospective analysis was performed for the clinical data of patients who underwent alar reduction from February 2019 to June 2022. A spindle-shaped incision line was designed along the outer edge of the base of the nasal lobule, with a width of 4-5 mm and a length of 8-12 mm. The incision line was 1-2 mm away from the alar groove, and the inner side of the design line was extended to the inside of the nasal vestibule. After the incision was made, the subcutaneous tissue was undermining dissected with curved sharp scissors, and the shape of the extended excision tissue was similar to that of jujube core. After reduction, the incision was closed with vertical mattress suture. The surgical effect and complications were followed up after surgery, and an independent attending plastic surgeon evaluated the outcome and scarring based on photos before and at the last postoperative follow-up using the global aesthetic improvement scale (GAIS) and the Vancouver scar scale (VSS). GAIS is graded as 1, 2, 3, 4, and 5 points, and the lower the score, the better the improvement(≤3 points as effective improvement). VSS includes four parameters: color (0-3 points), thickness (0-4 points), vascular distribution (0-3 points), and softness (0-5 points). The higher the score, the more significant the scar is.Results:A total of 20 patients were enrolled, including 6 males and 14 females, aged 20 to 33 years, with an average age of 24.9 years. Before the operation, there were different degrees of alar flare and alar hypertrophy. After surgery, 13 patients had mild swelling, ecchymosis, which resolved after 3 days. There were no major complications as infection, incision dehiscence, and delayed healing. After 3 to 16 months of postoperative follow-up, 2 patients gradually developed cartilage deformation and affected the appearance of the nostrils 6 to 9 months after surgery due to the combination of rib-based rhinoplasty, and the satisfactory results were obtained after revision surgery. The symmetry of the nostrils was significantly improved. The GAIS score of 20 patients was (1.20±0.41) points, of which, 16 patients were rated as 1 point and 4 patients were rated as 2 points, all of which met the improvement criteria, and the VSS score was (1.45±0.60) points, in which the average score for color, thickness, vasculature and compliance are 0.60, 0.05, 0.55 and 0.30 points respectively.Conclusion:The application of jujube core-shaped tissue resection technique for alar reduction can increase the amount of tissue removal with the same incision width, which can not only fully narrow the alar effectively but also correct the hypertrophy of the alar tissue.

Objective:To evaluate the utility of the 9-gene panel as a differential diagnostic method for thyroid nodules within determinate cytological diagnosis and as a parallel diagnostic method for thyroid fine-needle aspiration (FNA) cytology.Methods:579 liquid-based cytology samples from 544 patients were collected after thyroid FNA diagnosis in our hospital from December 2014 to April 2021. Mutations at any site of 9 genes, namely, BRAF, NRAS, HRAS, KRAS, GNAS, RET, TERT, TP53, and PIK3CA as recorded by the Catalogue of Somatic Mutations in Cancer (COSMIC), were analyzed by next-generation sequencing. Taking postoperative histopathology and cytology results with definite benign or malignant diagnosis as the gold standard, the diagnostic efficacy of the 9-gene panel as a reclassified method for thyroid nodules with indeterminate cytological diagnosis and as a parallel diagnostic method for thyroid FNA cytology were evaluated and compared with that of the BRAF V600E single-gene detection method.Results:Of the 579 thyroid nodules, 196 (33.85%) were Bethesda Ⅱ, 11 (1.90%) were Bethesda Ⅲ, 31 (5.35%) were Bethesda Ⅳ, 27 (4.66%) were Bethesda Ⅴ, and 314 (54.23%) were Bethesda Ⅵ, as diagnosed by thyroid FNA cytology. Among these 579 thyroid nodules, 275 were tested positive for 9-gene mutations, with a mutation rate of 47.5%. Of the 329 thyroid nodules surgically removed, 30 (9.12%) were benign, 5 (1.52%) were borderline, and 294 (89.36%) were malignant. Regarding borderline nodules as malignant nodules, the mutation rates of the 9 genes in the 299 malignant thyroid nodules from high to low were BRAF 62.21% (186/299), NRAS 5.02% (15/299), HRAS 1.00% (3/299), PIK3CA 0.67% (2/299), GNAS 0.67% (2/299), KRAS 0.33% (1/299), TP53 0.33% (1/299), TERT 0.33% (1/299) and RET 0.00% (0/299). The malignant risks of the 9 genes from high to low were BRAF 100% (186/186), PIK3CA 100.00% (2/2), GNAS 100.00% (2/2), TERT 100.00% (1/1), TP53 100.00% (1/1), NRAS 78.95% (15/19), HRAS 75.00% (3/4), and KRAS 50.00% (1/2). For thyroid nodules of Bethesda Ⅲ-Ⅳ (indeterminate diagnosis), the sensitivity (SN) of the 9-gene panel in diagnosing thyroid cancer is 34.48% (10/29), the specificity (SP) is 61.54% (8/13), and the accuracy is 42.86% (18/42); whereas the SN of the BRAF V600E detection method is 0%. Therefore, the diagnostic efficiency of the 9-gene panel is significantly better than that of BRAF V600E single gene detection. For thyroid nodules of Bethesda Ⅱ-Ⅵ, the SN of the 9-gene panel in diagnosing thyroid cancer was 68.83% (254/369), the SP was 90.00% (189/210), the accuracy was 76.51% (443/579), and the area under the curve (AUC) was 0.79; whereas the SN of BRAF V600E single-gene detection in diagnosing thyroid cancer was 63.69% (235/369), the SP was 99.52% (209/210), the accuracy was 76.68% (444/579), and the AUC was 0.82. The SP of BRAF V600E detection is higher than that of the 9-gene panel ( P＜0.01), but there is no significant difference in SN, accuracy (both P＞0.05), and AUC ( Z=0.85, P=0.396) between them. Gene mutations indicating poor prognosis were detected in 4 nodules of papillary thyroid carcinoma and 1 nodules of follicular thyroid carcinoma, including 2 nodules with TERT and BRAF V600E co-mutations, 1 nodule with TP53 mutation, and 2 nodules with PIK3CA mutation. Conclusions:As a reclassified method for thyroid lesions with indeterminate cytological diagnosis, the 9-gene panel is better than BRAF V600E single gene detection. As a parallel diagnostic method of thyroid FNA cytology, the 9-gene panel has similar diagnostic efficacy as BRAF V600E single-gene detection. The 9-gene panel can detect individual cases with gene mutations indicating poor prognosis. The identification of patients with these special gene mutations has certain implications for the clinical management of them.

Objective To investigate the screening and prevalence of tuberculosis among freshmen in different schools in Baoding City,and provide reference for tuberculosis control in schools.Methods Screening data of tu-berculosis and tuberculin test(PPD)of freshmen from 156 schools in different regions of Baoding City from Septem-ber 2021 to March 2022 were collected.PPD screening results of students from different regions and different school stages were analyzed and compared.Results A total of 68 177 freshmen from 156 schools were investigated for suspected symptoms and close contact history of pulmonary tuberculosis.PPD screening was conducted on 63 939 students.13 821 students were PPD positive,with a positive rate of 21.62％.3 083 students were strongly posi-tive,with a strong positive rate of 4.82％.15 cases of tuberculosis were found,and the reported incidence was 23.46/100 000.PPD positive rate and strong positive rate as well as incidence of tuberculosis in students in different school stages presented statistically significant differences(all P＜0.01).Positive rate and strong positive rate in students in different school stages showed upward trends(all P＜0.01).PPD positive rate and strong positive rate of students from schools in plain and mountainous areas presented statistically significant differences([22.28％vs 17.89％];[4.85％vs 3.62％],both P＜0.01).PPD positive rate and strong positive rate between students from boarding junior school and non-boarding junior school were significantly different,respectively([23.94％vs 21.60％];[5.07％vs 3.56％],both P＜0.01).Conclusion It is necessary to strengthen tuberculosis screening and health education for freshmen,especially those from boarding schools in plain areas,screening latent Mycobac-terium tuberculosis infection as early as possible,take corresponding measures to prevent and control the spread of tuberculosis,and reduce the risk of tuberculosis.