[Determination of Perchloroethylene in blood by headspace gas chromatography-mass spectrometry].

Objective: To establish a method for determination of Perchloroethylene (PCE) in blood by headspace gas chromatography-mass spectrometry (HS/GC-MS) . Methods: From Dctober to December 2021, A total of 3 mL blood samples were taken into a 10 mL headspace bottle, after heated at 60 ℃ for 30 mins, PCE in the top air was separated by VF-WAXms capillary column and detected by GC-MS. The retention time and external standard method were used for qualitative and quantitative analysis of PCE in samples, respectively. Results: There was good linear relationship in the range of 5.09-200.17 µg/L. The linear correlation coefficient was 0.9993.The detection limit was 0.21 µg/L and the lower limit of quantitation was 0.70 µg/L. The recovery rates of samples with different concentrations were 95.3%-103.8%. The intra-batch relative standard deviations (RSD) were 3.2%-4.6%, and inter-batch RSD was 4.0%-6.1%. The samples can be stored at 4 ℃ for three days and at -20 ℃ for seven days. Conclusion: This method is proved to be simple, practical and highly sensitive, which is suitable for the determination of PCE in blood.

[Evaluation of the determination of hydrogen sulfide in the air of workplace by the detection tube method].

Objective: To evaluate the accuracy and applicability of detection tube method for quantitative detection of hydrogen sulfide in workplace air. Methods: In September 2021, the lower limit of quantification, accuracy, precision, environmental factors, interfering gases and other performance indicators of the method for determining hydrogen sulfide in the air of workplace were verified by the detection tube, and the results were compared with those of GB 11742-89 "Standard method for hygienic examination of hydrogen sulfide in air of residential areas-methylene blue spectrophotometric method" to evaluate the application effect of the detection tube method for quantitative detection of hydrogen sulfide in workplace air. Results: There was no significant difference in the results of 2.83 mg/m(3), 4.25 mg/m(3) and 17.00 mg/m(3) hydrogen sulfide concentration between the two methods (P>0.05) , but there was significant difference in the results of 8.50 mg/m(3) concentration (P<0.05) . The lower limit of quantification of hydrogen sulfide in workplace air was 2.83 mg/m(3), the accuracy was 96.0%-111.0%, and the precision was 0.70%-6.64%. Under the condition of 4 ℃, the measured results decreased by 3.39%-13.10%. When the humidity was 50%-80%, the relative error of the average measured value was -1.67%-4.44%. Interference gases that may exist in the workplace (including carbon dioxide, carbon monoxide, mercaptans, nitrogen oxides, sulfur dioxide, etc.) did not interfere with the results of the test tube. Conclusion: The accuracy and precision of the detection tube method meet the detection requirements. The method is simple, rapid and easy to be popularized, and can be used for the rapid detection of hydrogen sulfide gas concentration in the workplace.

An observational study on the safety of COVID-19 vaccination in patients with myasthenia gravis.

OBJECTIVE: There is concern that the coronavirus disease (COVID-19) vaccine may trigger or worsen autoimmune diseases. The objective of this study was to determine the impacts of COVID-19 vaccination on symptom severity in patients with myasthenia gravis (MG). METHODS: A total of 106 enrolled patients with MG who were vaccinated against COVID-19 were followed up, and a questionnaire was used to document in detail the exacerbation of muscle weakness after vaccination and all other uncomfortable reactions after vaccination. Demographic, clinical characteristics, medication, and vaccination data were collected by follow-up interview. The main observation outcome was whether the MG symptoms of patients were exacerbated. The definition of exacerbation is according to the subjective feeling of the patient or a 2-point increase in daily life myasthenia gravis activity score relative to before vaccination, within 30 days after vaccination. RESULTS: Of 106 enrolled patients [median age (SD) 41.0 years, 38 (35.8%) men, 53 (50.0%) with generalized MG, 74 (69.8%) positive for acetylcholine receptor antibody, and 21 (19.8%) with accompanying thymoma], muscle weakness symptoms were stable in 102 (96.2%) patients before vaccine inoculation. Muscle weakness worsened in 10 (9.4%) people after vaccination, of which 8 patients reported slight symptom worsening that resolved quickly (within a few days). Two (1.9%) of patients showed serious symptom aggravation that required hospitalization. CONCLUSION: Our results suggest that inactivated virus vaccines against COVID-19 may be safe for patients with MG whose condition is stable. Patients with generalized MG may be more likely to develop increased muscle weakness after vaccination.

[Analysis of clinical characteristics and related genetic variation of juvenile myasthenia gravis].

Objective: To analyze the clinical characteristics and related genetic variation of juvenile myasthenia gravis (MG) patients. Methods: We collected the clinical data of adolescent MG patients who were treated in the Department of Neurology of the First Affiliated Hospital of Sun Yat-sen University from June 2019 to May 2020. After obtaining the patient's informed consent, the blood samples were collected. The Whole Exome Sequencing (WES) was performed on peripheral blood samples. And use biological information software and SPSS 22.0 for data processing and result analysis. Results: According to the inclusion and exclusion criteria, 54 patients with juvenile MG were included, 28 males and 26 females. And the average age of onset was (3.79±0.89) years. Among the enrolled patients, there were 52 (96.3%) patients with ocular MG, the MG-ADL scores of 54 patients were (3.44±0.44) points, and the titer of AChR antibody was (5.88±2.45) nmol/L. Two patients had thymic hyperplasia, and 5 patients had a family history of MG.A total of 169 variant genes were found in 54 patients, of which TTN gene variants had the largest number, with a total of 17 variants (31.5%). In the TTN gene variant group, 7(41.2%) patients had eye fixation symptoms, and 4 (10.8%) patients in the non-mutation group had eye fixation symptoms. And The difference between the two groups was statistically significant (P=0.016). In addition, the synaptic nucleus envelope protein-1 (SYNE1) and the ryanodine receptor-1 (RYR1) gene variations were also found in 7 cases (13.2%), and no clear relationship between these gene variations and clinical manifestations of MG was found. Conclusions: The incidence of juvenile MG was preschoolers with no gender difference, and ocular MG was more common. The proportion of TTN gene variation in adolescent MG was higher, suggesting that this gene may be a potential therapeutic target for juvenile MG patients.

[Clinical characteristics and outcomes of myasthenia gravis patients with double positive antibodies against acetylcholine receptor and muscle-specific tyrosine kinase].

Objective: To investigate the clinical manifestations, treatment characteristics and outcomes of myasthenia gravis (MG) dually positive for anti-acetylcholine receptor antibody (AChR-Ab) and anti-muscle-specific tyrosine kinase antibody (MuSK-Ab). Method: MG patients hospitalized in the First Affiliated Hospital of Sun Yat-sen University from August 2017 to November 2020 were retrospectively collected. Thirty-four MuSK-Ab positive MG (MuSK-MG) patients, 11 double-antibodies positive MG (DP-MG) patients, and 80 AChR-Ab positive MG (AChR-MG) patients were included and allocated to three different groups. The clinical data of patients in the three groups were collected, and the differences of demographic characteristics, clinical manifestations and treatment outcomes between DP-MG patients and AChR-MG and MuSK-MG patients were analyzed. Result: The proportion of female and male patients in DP-MG group was 7/11 and 4/11 respectively, and the onset age of DP-MG was (41±27) years.The difference in gender distribution between DP-MG and AChR-MG groups was statistically significant (P<0.05). The proportion of extraocular muscle involvement in the DP-MG and MuSK-MG groups (8/11 and 52.9%) was lower than that in the AChR-MG group (83.8%), and the difference was statistically significant (P<0.05). The incidence of myasthenia crisis in DP-MG and MuSK-MG groups (54.5% and 61.8%) were higher than that in AChR-MG group (20.0%), with astatistically significant difference(P<0.05). The positive rate of neostigmine test in DP-MG and MuSK-MG groups(8/11 and 74.2%) were lower than that of AChR-MG group (96.8%), and the positive rate of low frequency repetitive nerve stimulation (RNS) in DP-MG group (5/10) was lower than that in AChR-MG group (85.1%), with statistically significant differences (all P<0.05). MuSK-Ab titer was positively correlated with the course of disease (r=0.466, P<0.05), and antibody titer decreased after symptom improvement (P<0.05). The response of patients in DP-MG and MuSK-MG groups to cholinesterase inhibitors (2/11 and 9.1%) was worse than that in the AChR-MG group (66.3%), and the incidence of side effects in the two groups (5/11 and 39.4%) was higher than that in the AChR-MG group (15.0%), with statistically significant differences (all P<0.05). There were 4 DP-MG patients underwent thymectomy, and the pathological results detected two cases of thymoma and two cases of thymic hyperplasia. Subsequent follow-up showed that 5 (5/11) DP-MG patients achieved minimal manifestation status or better status. Conclusion: The gender distribution, age of onset, pharmacological characteristics and electrophysiological examination of DP-MG patients were similar to those of MuSK-MG patients, but the severity of DP-MG patients was between that of AChR-MG and MuSK-MG patients.

[To attach great importance to the identification of refractory myasthenia gravis].

Refractory myasthenia gravis is an intractable state during treatment. The common causes of refractory treatment in most patients include: overwork, malnutrition, infections, insomnia, cognitive and emotional disorders, and so on. Only targeting the poor curative effect from the surface of the intractable state caused indecisive decisions and is difficult to win a success. Therefore, identifying "refractory state" can not only see the essence through the phenomenon, but also apply the right medicine, thereby killing two birds with one stone.

Gender-specific SBNO2 and VPS13B as a potential driver of osteoporosis development in male ankylosing spondylitis.

To identify the critical genes and pathways that related to OP development in male AS patients, bioinformatic gene analysis and qRT-PCR validation were performed. SBNO2 and VPS13B were identified as the potential target for OP development, which may be valuable for the prevention of OP in male AS patients. INTRODUCTION: Osteoporosis (OP) is common in men with ankylosing spondylitis (AS). The specific pathogenesis of OP in AS, however, is still unclear. The present study attempted to identify potential genes associated with the development of OP in males with AS. METHODS: Gene expression profiles were downloaded from the GSE73754 and GSE35959 datasets from the Gene Expression Omnibus (GEO). Data from OsteoporosAtlas were downloaded as a supplement. Differentially expressed genes (DEGs) were determined with the limma package. The overlapping DEGs between male AS-related genes and OP-related genes were determined. The DEGs were validated by qRT-PCR in the blood samples of males with AS. Weighted gene co-expression network analysis (WGCNA) was utilized to establish a co-expression network to identify the hub genes. RESULTS: A total of 17 overlapping DEGs were identified; 6 genes in 17 overlapping DEGs were verified as the essential genes in the pathogenesis of OP in male AS by qRT-PCR analysis. After WGCNA, the modules of MEblue (> 0.6) and MEred (> 0.8) were screened out by the correlation analysis and were determined to function mainly in MAPK signaling pathway and osteoclast differentiation. Analysis of the two modules revealed VPS13B and SBNO2 as key genes due to the high degree of correlation. Both genes play an important role in bone metabolism regulation in male AS. Two hub genes MYD88 in MEblue and NCK1 in MEred with high degree of connectivity were selected. CONCLUSIONS: Gender-specific SBNO2 and VPS13B may be key genes involved in OP in male AS.

Targeted regulation of miR-195 on MAP2K1 for suppressing ADM drug resistance in prostate cancer cells.

Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "Targeted regulation of miR-195 on MAP2K1 for suppressing ADM drug resistance in prostate cancer cells, by J.-Y. Zhang, Y.-N. Li, X. Mu, Z.-L. Pan, W.-B. Liu, published in Eur Rev Med Pharmacol Sci 2018; 22 (24): 8599-8608-DOI: 10.26355/eurrev_201812_16623-PMID: 30575899" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/16623.

[Risk factors analysis for steroid-resistant acute graft versus host disease after haploidentical hematopoietic stem cell transplantation].

Objective: To analyze the risk factors of steroid resistant acute graft- versus-host disease (aGVHD) after haploidentical hematopoietic stem cell transplantation (haplo-HSCT) . Methods: The clinical data of adult patients with acute myeloid leukemia (AML) /Myelodysplastic syndrome (MDS) who developed aGVHD after haplo-HSCT in Peking University Institute of Hematology from January 1st, 2010 to December 31st, 2012 were retrospectively reviewed. Results: A total of 85 patients were enrolled in the study, including 55 males and 30 females, with a median age of 30 (19-67) years. After steroid therapy, there were 53 (62.4%) , 6 (7.1%) and 26 (30.6%) patients achieved complete remission (CR) , partial remission (PR) and non-remission (NR) , respectively. The CR rates of the grade Ⅰ/Ⅱ and Ⅲ/Ⅳ aGVHD by steroid therapy were 66.2% (51/77) vs 25.0% (2/8) (χ(2)=3.639, P=0.048) , respectively. The CR rates of the patients with aGVHD involving 1 target organ and 2 target organs were 77.4% (48/62) vs 21.7% (5/23) (χ(2)=22.157, P<0.001) . The CR rates of patients with standard risk (SR) and high risk (HR) Minnesota risk score was 67.5% (52/77) vs 12.5% (1/8) (χ(2)=7.153, P=0.004) . The mononuclear cells≥8.33×10(8)/kg and the HR Minnesota risk score were independent risk factors for steroid-resistant aGVHD in multivariate analysis. Between Minnesota risk score SR (77 cases) and HR (8 cases) groups, the OS rates at 22 months after transplantation were (90.3±3.8) %vs (75.0±15.3) % (χ(2)=2.831, P=0.092) . After steroid treatment for aGVHD, the OS rates at 22 months in the CR group (53 cases) and non-CR group (32 cases) were (95.2±3.4) %vs (78.6±7.9) % (χ(2)=5.287, P=0.021) respectively. Conclusion: The Minnesota risk score and mononuclear cells count are effective tool for predicting steroid-resistant aGVHD after haplo-HSCT.

[A bibliometric analysis on cohort study of liver cancer in China].

Objective: To retrospectively analyze the application trend of cohort study in the field of liver cancer in past 27 years and to look forward to the future development trend. Methods: Chinese and English papers reporting the cohort studies of liver cancer conducted in the mainland of China since 1991 were included. The literature management software was used to analyze the publication time, institution, type and objective of the studies and the follow-up performance. Statistical analysis was carried out by using SPSS 21.0. Results: The number and quality of the papers reporting liver cancer-related cohort studies increased significantly in past 27 years and a core English journal group of this field has formed. The average annual growth rates of Chinese and English papers published were 20.4% and 35.2% respectively. About 52.3% of the Chinese papers and 73.5% of the English papers were published in past five years and the quality of these papers was high. The Chinese papers published on Chinese core journals accounted for 49.2%, and the English papers published on SCI periodicals (IF>3) accounted for 47.3%. For the study objective, those published on the domestic journals mainly focused on the pathogenesis of hepatoma (41.5%), studies with large sample size was the common form. The SCI studies mainly focused on the prognosis of liver cancer (40.7%). High-quality SCI papers are more interested in the studies of prognosis, and survival analysis was the common form. Conclusions: The application of cohort study in the field of liver cancer gradually increased in China. Large-scale study and prognosis analysis were conducted commonly. However, it is necessary to further improve the researchers' understanding of cohort study, improve the follow-up quality, and increase the application of scientific evaluation methods, such as survival analysis, for the better solving of clinical problems.

Synthesis, structure, magnetic and half-metallic properties of Co2-x Ru x MnSi (x = 0, 0.25, 0.5, 0.75, 1) compounds.

A series of Co2-x Ru x MnSi (x = 0, 0.25, 0.5, 0.75, 1) Heusler compounds were successfully synthesized. The heat-treatment conditions were crucial to make the materials form a single phase with a Heusler structure. With increasing Ru content, the half-metallic gap, lattice parameters and magnetization are continuously adjustable in a wide range. The Co2-x Ru x MnSi (x = 0, 0.25) compounds are rigorous half-metals and show a T 3 dependence of resistance at low temperature. The Co2-x Ru x MnSi (x = 0.5, 0.75, 1) Heusler compounds are the nearly half-metallic materials and show a semiconductive dependence of resistance at low temperature. The experimental magnetization is consistent with that in theory and follows the Slater-Pauling rule. The Curie temperature is higher than 750 K for all Co2-x Ru x MnSi Heusler compounds.

[Characteristics of electromyography in 111 patients with generalized myasthenia gravis: a retrospective study].

Objective: To retrospectively analyze the characteristics of the electromyography (EMG) study in generalized myasthenia gravis (gMG) patients. Methods: A total of 111 gMG patients were enrolled. Patients were divided into two groups: 36 severe patients discontinuing pyridostigmine bromide (PB) for 8 hours were included in 8 h group, and 75 g MG patients discontinuing PB for at least 18 hours were included in>18 h group. The clinical information and EMG study data were collected and analyzed. Results: There were statistically significant differences in the initial location of the myasthenia muscle (P=0.027), the affected muscle detected by the EMG (P=0.015) and quantitative myasthenia gravis (QMG) score (P<0.01) between the two groups. Comparisons in each group revealed that the highest positive rate of low-frequency repetitive nerve stimulation (RNS) of facial in 8 h group and>18 h group was 94.4% and 60.0%, respectively. Comparisons between the two groups showed that the positive rate of low-frequency RNS in 8 h group was significantly higher than that in>18 h group (94.4% vs 70.7%, χ(2)=8.115, P=0.004). In particular, the positive rate of RNS in facial nerves and the extent of the amplitude decrease under different electrical stimulations (1 Hz, 3 Hz, and 5 Hz) were dramatically higher in the 8 h group (P<0.01). Conclusions: For gMG patients, the facial and accessory nerve detection can improve the positive rate of RNS. Different muscles had various sensitivity to PB, and orbicularis oculi muscle seemed the least sensitive muscle to PB. For suspect MG patients in severe condition, only discontinuing PB medication for 8 h before low-frequency RNS testing can avoid the deterioration and also obtain similar positive rate.

Targeted regulation of miR-195 on MAP2K1 for suppressing ADM drug resistance in prostate cancer cells.

OBJECTIVE: Extra-cellular signal-regulated kinase/mitogen-activated protein kinase (ERK/MAPK) signaling pathway participates in cell proliferation, cycle and apoptosis. MAPK kinase 1 (MAP2K1) activates the ERK/MAPK pathway. The down-regulation of miR-195 is correlated with the onset and drug resistance of prostate cancer. Bioinformatics analysis identified complementary binding sites between miR-195 and MAP2K1. This study aimed to investigate the effect of miR-195 on the proliferation, apoptosis and adriamycin (ADM) resistance of prostate cancer cells. MATERIALS AND METHODS: Dual-Luciferase reporter gene assay confirmed targeted regulation between miR-195 and MAP2K1. ADM resistant cell line DU145/ADM and PC-3/ADM were generated for comparing the miR-195 and MAP2K1 expression. Apoptosis was measured by flow cytometry and caspase-3 activity was quantified. Cultured cells were treated with miR-195 mimic, followed by quantitative real-time PCR (qRT-PCR) was used for MAP2K1 expression. Western blot measured MAP2K1, ERK1/2 and phosphorylated ERK1/2 (p-ERK1/2) expression, and flow cytometry quantified cell apoptosis, followed by EdU staining for cell proliferation. RESULTS: Targeted regulation existed between miR-195 and MAP2K1 mRNA. Drug-resistant cells had lower miR-195 than parental cells, whilst MAP2K1 expression was higher. Under ADM treatment with IC50 concentration, drug resistant cells showed lower apoptosis. The transfection of miR-195 decreased MAP2K1 expression and p-ERK1/2, elevated cell apoptosis and suppressed EdU positive rate or cell proliferation. CONCLUSIONS: The down-regulation of miR-195 is correlated with ADM resistance of prostate cancer cells. The over-expression of miR-195 weakens cancer cell proliferation, facilitates cell apoptosis and decreases ADM resistance via targeted inhibition on MAP2K1 expression and ERK/MAPK signal pathway.

[A case of facial paralysis caused by granulocytic sarcoma of the external auditory canal].

Summary A male patients at 11 years of age, was hospitalized for the right ear pain and mouth deviation for five days on August 30, 2016, accompanied by right hypophasis, right ear hearing loss, tinnitus, without otorrhea and vertigo. Patient was diagnosed as acute promyelocytic leukemia in 2008. After standardized chemotherapy, it was completely relieved and the blood and bone marrow images were almost restored to normal. Physical examination: The skin of the right external auditory canal is obviously swollen, without rupture on the surface, and the tympanic membrane cannot be seen. The drooping of the left angle of the mouth, the right eyelid is not closed completely, the right nasolabial groove and forehead line is shallower. House-Brackmann facial nervous system Ⅲ. Routine blood: the leucocyte 10.31×109/L, more than in the normal range. Pure tone measurement showed that right ear conductive deafness, air-bone conduction difference of each frequency range 50 to 75 dB.Mastoid CT showed that right mastoid gasification is good, the right external auditory canal, middle ear cavity and mastoid airway are filled with low-density soft tissue shadows, the bone wall of the external auditory canal was not significantly enlarged or damaged. The auditory bone is intact, surrounded by a large number of soft tissue shadows, no obvious abnormalities in the inner ear. Primary diagnosis: Middle ear cholesteatoma (right);External auditory canal tumor (right);Peripheral facial paralysis (right).

[Establishment of DNA Genetic Marker Identification System for Plant Evidence].

OBJECTIVES: To establish a species identification system based on DNA genetic markers for plant evidence. METHODS: Two hundred common plants in Shanghai were collected and identified by morphological characteristics. The primers of gene segments rbcL, matK, and ITS were designed and amplified. The PCR amplicon was detected by agarose gel electrophoresis. After the sequencing, the universality and the identification capacity of the three markers were evaluated. RESULTS: The success rate of amplification was in order of rbcL （99.5%） > matK （92.5%） > ITS （86.0%）. The identification capacity of the combination of rbcL and matK was better than that of rbcL or matK, by which most plant species could be identified to the genus or higher. ITS was not suitable to be a unique marker because of its unstable result, but it still could be a powerful supplement. The identification capacity of the combination of rbcL, matK and ITS was higher than that of rbcL and matK, by which most plant species could be identified to the genus or lower. CONCLUSIONS: The identification system with the combination of rbcL, matK and ITS as markers has excellent universality for plant evidence, which can distinguish most plant species to the genus or lower.

Antifungal activity of the bioactive substance from Bacillus atrophaeus strain HAB-5 and its toxicity assessment on Danio rerio.

The prevalence of pathogen inhibitors bacteria has motivate the study for antimicrobial compounds. Bioactive fungicide have always received considerable attention. A bacterial isolated strain HAB-5 showed antifungal activity against plant fungi. Based on morphological, physiological, biochemical and 16SrDNA sequence analysis, the strain was identified to be a Bacillus atrophaeus. This strain possessed a broad spectrum antifungal activity against various plant pathogenic fungi. Extraction of antifungal substance was performed and the crude extract had potent antifungal ability and showed great potential for swelling and inhibiting spore germination. This antifungal displayed heat stability and active in a wide pH range 5.0-10.0. Moreover no reduction was found in its activity after enzyme treatment. The toxicity test was evaluated in Danio rerio. The acute toxicity test indicated that the 24, 48, 72, 96h LC50 values of UMTLS to the zebrafish were 14.4, 13.8, 13.4, and 12.9%, respectively. Based on the results obtained in this study, antifungal substance was not toxic to zebra. Analyses of disease suppression showed that HAB-5 was effective to reduce the incidence of anthracnose symptoms on mango fruits, also prevent disease infection and protect tobacco seedling from Phytophtora nicotianae. The bioactive substance from Bacillus atrophaeus HAB-5 could be a candidate in the generation of new antifungal agents in crop.

[Expression of B cell transposition gene 3 in pancreatic ductal adenocarcinoma and its prognostic value].

Objective: To detect the expression of B cell transposition gene 3(BTG3) in pancreatic ductal adenocarcinoma(PDAC), and explore its relationship with postoperative recurrence and metastasis of tumor. Methods: Six self-paired frozen PDAC specimens and 3 normal pancreatic tissues from the Second Hospital of Jiaxing Affiliated to Jiaxing University were collected and the expression of BTG3 was detected by qPCR. Ten normal pancreatic tissues and 52 cases of PDAC tumor and paracarcinomatous tissues from the Second Hospital of Jiaxing Affiliated to Jiaxing University were collected from June 2009 to December 2016. The expression of BTG3 and relationship among BTG3 and clinicopathological characteristics of PDAC and patients' prognosis were detected and analyzed using immunohistochemistry.χ(2) test, Kaplan-Meier method and Cox regression model were used to analyzed the data. Results: The results of qPCR showed that expression level of BTG3 in PDAC (0.63±0.17) was lower significantly than that in paracarcinomatous (0.96±0.04) and normal tissues (1.00)(t=4.673, 5.502; both P<0.05). Immunohistochemistrv showed that BTG3 mainly expressed in the cytoplasm.The high expression rate of BTG3 in PDAC tumor tissues was 25.0%(13/52), which was remarkably lower than that in paracarcinomatous tissues(65.4%) and normal liver tissues(7/10)(χ(2)=17.120 and 5.849, both P<0.05). The low expression of BTG3 in PDAC was correlated with primary tumor, and TNM stage(χ(2)=7.704, P=0.006; U=154.000, P=0.018, respectively). Survival analysis showed that disease free survival rate of patients with low expression of BTG3 was significantly less than that with high expression(χ(2)=192.493, P<0.01). The Cox multivariate analysis demonstrated that low expression of BTG3 was independent risk factors for disease free survival in patients with PDAC after a curative resection(RR=3.366, 95%CI: 1.040-10.889, P=0.043). Conclusion: BTG3 may be involved in the occurence and development of tumor, and its low expression may be associated with poor prognosis in patients with PDAC.