Rapid screening of 28 alkaloids in food poisoning samples by liquid chromatography-tandem mass spectrometry / 中国热带医学

@#Abstract: Objective　To investigate a poisoning incident caused by eating eight treasure congee, and establish liquid chromatography (LC)-mass spectrometry (MS)/MS screening method of 28 alkaloids to provide references for disposal of similar poisoning incidents. Methods　LC-MS/MS was used for screening 28 alkaloids in the urine, eight treasure congee and food raw material, and the detected alkaloids were quantified. Samples were extracted with 0.4% formic acid aqueous solution and separated by a Acquity UPLC BEH C18 column (1.7 μm, 100 × 2.1 mm). Acetonitrile-0.2% formic acid aqueous solution was used as the mobile phase and gradient elution was adopted. The ionization mode was electrospray positive ionization mode, and the detection method was multi-reaction monitoring (MRM). Analytes were quantified with the external standard method. Results　In the concentration range of 0-100 ng/mL, the linear correlation coefficient r were greater than 0.999 for 28 alkaloids. The recovery of 28 alkaloids in urine sample ranged from 63.0% to 105.0%, and the relative standard deviations (RSDs) were between 5.8% and 8.6%. The recovery of 28 alkaloids in eight treasure congee sample ranged from 72.0% to 109.0%, and the RSDs were between 6.3% and 9.7%. The recovery of 28 alkaloids in semen sesami nigrum sample ranged from 60.0% to 95.0%, and the RSDs were between 4.8% and 8.2%. Hyoscyamine (2 380.0 ng/mL), scopliamine (3.6 ng/mL) and rac-anisodamine (4.7 ng/mL) were detected in the patient's urine. Hyoscyamine (63.3 μg/g), scopliamine (5.7 μg/g) and rac-anisodamine (2.1 μg/g) were detected in eight treasure congee. Hyoscyamine (901.0 μg/g), scopliamine (80.0 μg/g) and rac-anisodamine (30.1 μg/g) were detected in the seed of Datura stramonium L. The ratio of scopliamine and hyoscyamine in the seed of D. stramonium was 1∶11, which complies with the characteristics of D. stramonium L. In urine sample, the proportion of scopliamine and rac-anisodamine was 0.15% and 0.20%, and hyoscyamine accounted for 99.65%. Conclusion　Seed morphology, the content range and proportion of three alkaloids are all in accord with the characteristics of D. stramonium. Combined with the clinical symptoms of atropine poisoning, it can be deduced that this incident is a family food poisoning caused by accidental consumption of seed of D. stramonium L. The method can provide technical support for the clinical diagnosis and treatment of alkaloid poisoning patients, and also provide a basis for emergency detection and disposal of alkaloid poisoning events.

Loneliness and associated factors among adolescents with mixed anxiety and depressive disorder / 中国学校卫生

Objective@#To investigate loneliness and associated factors among adolescents with mixed anxiety and depressive disorder(MADD), and to provide reference for drawing up effective and targeted interventions.@*Methods@#Using convenience sampling method, 265 adolescents with MADD in Daqing Third Hospital were selected from September 2020 to June 2021. General information questionnaire, Pittsburgh sleep quality index(PSQI), Resilience Scale for Chinese Adolescents(RSCA), Child and Adolescent Peer Relationship Scale and UCLA Loneliness Scale were used to investigate the status and influencing factors of loneliness among adolescents with MADD.@*Results@#The average score of UCLA among 265 adolescents with MADD was (56.49±10.83). The results of univariate analysis showed that age, gender, burden of medical expenses, drinking behavior and parents migrant work had statistically significant differences in the UCLA scores. The results of Pearson correlation analysis showed that loneliness in MADD adolescents was negatively correlated with psychological resilience( F/t=57.65, -60.62, 21.92, 8.52, 16.22, P <0.01), and positively correlated with sleep quality and interpersonal distress( F/t=-0.69, 0.76, 0.50, P <0.01). The results of multiple stepwise regression analysis showed that phase of study, sex, burden of medical expenses, interpersonal distress, sleep quality and resilience were the influencing factors of loneliness among adolescents with MADD( B=0.11, 0.13, 0.09, 0.46, 0.10,-0.24, P <0.01).@*Conclusion@#Adolescents with MADD have moderate loneliness, which needs to be improved. Nursing staff should pay attention to the negative emotional experience such as loneliness among adolescents with MADD, and reduce their loneliness by improving sleep quality and resilience, reducing interpersonal distress.

Prokaryotic expression, purification and antiserum preparation of severe acute respiratory syndrome coronavirus 2 nucleocapsid protein / 第二军医大学学报

Objective To express and purify the recombinant nucleocapsid (N) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and prepare antiserum from immunized mice. Methods The prokaryotic plasmid pET28a-N containing SARS-CoV-2 N gene was transformed into Escherichia coli BL21 (DE3). The expression of recombinant SARS-CoV-2 N protein was induced by isopropyl-β-D-thiogalactopyranoside. The Ni-NTA affinity chromatography column was used to purify the recombinant SARS-CoV-2 N protein, and antiserum was obtained from the BALB/c mice immunized with recombinant SARS-CoV-2 N protein combined with manganese adjuvant through intramuscular and subcutaneous injections. The reactions of recombinant SARS-CoV-2 N protein with SARS-CoV-2 N monoclonal antibodies and severe acute respiratory syndrome coronavirus (SARS-CoV) N polyclonal antibodies were detected by Western blotting. The reaction of mouse antiserum with the recombinant SARS-CoV-2 N protein expressed in the cells transfected with eukaryotic expression plasmid was examined by indirect immunofluorescence assay. Results The recombinant SARS-CoV-2 N protein was successfully induced and expressed as a soluble protein with a molecular weight of about 55 000. High concentration of purified protein was obtained. The results of Western blotting showed that the recombinant SARS-CoV-2 N protein could be specifically recognized by the SARS-CoV-2 N monoclonal antibodies and the SARS-CoV N polyclonal antibodies. The prepared mouse antiserum could also correctly recognize the recombinant SARS-CoV-2 N protein expressed in mammalian cells by indirect immunofluorescence assay. Conclusion Recombinant SARS-CoV-2 N protein has been successfully expressed and purified from the prokaryotic expression system, and mouse antiserum has been prepared, which lays a foundation for establishing a rapid SARS-CoV-2 diagnostic tool and further studying the function of SARS-CoV-2 N protein..

Analysis of amino acid variations of major proteins from severe acute respiratory syndrome coronavirus 2 / 第二军医大学学报

Objective To identify key amino acid variations of major proteins from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by biophysical methods. Methods Through amino acid sequence alignment, classification of variant amino acid residues, three-dimensional structure reconstruction of proteins, and electrostatic interaction analysis of amino acid residues, the key amino acid variations of major proteins from SARS-CoV-2 was analyzed with RaTG13, the bat coronavirus with the highest homology, as the reference. Results At least ten amino acid variations that affect the possible electrostatic interactions were identified in RNA-dependent RNA polymerase (RdRp), exoribonuclease (ExoN), uridylate-specific endoribonuclease (NendoU), and spike (S) protein from SARS-CoV-2. These variations may affect the spatial conformation and biological functions of the proteins. Conclusion The key amino acid variations of the major proteins from SARS-CoV-2 have been preliminarily identified, providing clues for understanding the genetic, pathogenic and epidemiological characteristics of the virus..

Theoretical and Clinical Studies of Integrated Traditional Chinese Medicine and Western Medicine for Infertile Women with Diminished Ovarian Reserve / 中国实验方剂学杂志

Infertility with diminished ovarian reserve(DOR) is a major problem in the field of reproductive health and it has attracted great attention worldwidely.Function deficiency of the kidney is one of the fundamental pathogenesis for DOR.Traditional Chinese medicines(TCMs) have a long history with rich experience for the treatment of infertility.Some TCMs are very effective in the treatment of kidney deficiency for infertility with DOR.The integrated TCMs and western medicine,and combination of disease differentiation and syndrome differentiation may help for diagnosis and treatment of infertility with DOR.We adopt the concept of unified treatment for special disease,and the methods and principle of treatment can be used.Therefore,we adopt the TCM concept of kidney-tonifying,blood-nourishing,liver-dispersing and spleen-invigorating.The TCMs kidney-tonifying formulae are added and subtracted.TCMs can regulate the reproductive function via multiple systems for simultaneous conditioning of follicular development and ovulation.At the same time,a hypothesis of " simultaneous conditioning of follicular development and ovulation" was proposed.Two-stage therapy with integrated TCMs and western medicine has been used,mainly for increasing the number of eggs,and improving follicle quality.The goal is to achieve simultaneous conditioning of follicular development and ovulation and ultimately for effective treatment of infertility with DOR.

Evodiamine inhibits growth of Huh7 cells and enhances their sensitivity to TRAIL / 中国病理生理杂志

AIM:To investigate the effects of evodiamine on the growth and apoptosis of human hepatocellular carcinoma Huh7 cells,and to illustrate the molecular mechanism that evodiamine enhances antitumor activity of tumors nec -rosis factor-related apoptosis-inducing ligand(TRAIL)in Huh7 cells.METHODS: The cell viability was measured by MTT assay.The cell cycle distribution was analyzed by flow cytometry.The apoptosis rate was determined by TUNEL stai-ning.The protein levels of cell cycle-and apoptosis-related proteins were detected by Western blot analysis.RESULTS:Treatment of Huh7 cells with evodiamine reduced the cell viability(P<0.05).Evodiamine induced cell cycle arrest in G2/M phase by upregulation of p27,cyclin B1, cell division cycle protein 2(Cdc2)and p-Cdc2.Evodiamine triggered apoptosis accompanied by cleavage of caspase-3 and poly(ADP-ribose)polymerase(PARP).Combination of evodiamine with TRAIL significantly reduced the cell viability and increased cleavage of caspase -3 and PARP as compared with the use of each agent alone.Moreover,evodiamine increased the expression of death receptor 5(DR5)in the Huh7 cells.CON-CLUSION:Evodiamine inhibits the cell growth by reducing the cell viability and inducing cell cycle arrest.Evodiamine also triggers cell apoptosis and enhances the sensitivity of Huh 7 cells to TRAIL by upregulating the expression of DR5.

Diversity of agronomic traits of Paris polyphylla var. chinensis and their correlation with rhizome yield and active compositions / 中国中药杂志

The supply deficiency of crude medicinal plant of Paris polyphylla var. chinensis has become a bottleneck for related medicinal industry. An important approach to increase herbal production is to breed high-yield cultivated variety, which characterized ideal plant morphology. In the present study, we collected 99 wild germplasm resources of P. polyphylla and then measured their 12 main agronomic traits and contents of polyphyllin Ⅶ,Ⅵ,Ⅱ,Ⅰ. Followed analyses were used to characterize those traits and explore the potential connection with herbal yield or quality. The results showed that: ①There was ample morphological diversity in wild P. polyphylla, whose variation of agronomic traits reduced according to followed order: content of polyphyllin, weight of dry rhizome, petiole length, stem length, petal length, pedicel length, sepal length, leaf width, leaf length, sepal width, leaf number, stamen number, petal number. ② Most of those traits were significantly correlated to each other and generally represented the characterization of photosynthetic organs or reproductive organ. ③The total content of polyphyllin Ⅶ,Ⅵ,Ⅱ,Ⅰvaried between 0.02% and 0.87% and averagedat 0.13%, which showed no significant correlation with any agronomic trait. ④Plant breeders should play more attention on those germplasm resources with large leaves, large sepals and high stem.

Analysis of the typical clinical features of posterior cruciate ligament rupture and comparison of arthroscopic surgery and conservative treatment / 中国内镜杂志

Objective To observe the clinical features of posterior cruciate ligament rupture and compare the efficacy of arthroscopic surgery and conservative treatment. Methods 128 patients, including 63 patients treated by arthroscopic surgery and 65 patients treated by conservative operation were included in the study. Statistical analysis was performed using SPSS 17.0 statistical software package. Results In the present study, after 24 month follow up, the PDT grade in the arthroscopic surgery group was better than that in conservative treatment group. The Lysol score in the arthroscopic surgery group was significantly higher that observed in the conservative treatment group (P < 0.05). There was no significantly difference for the Tiger score between the arthroscopic surgery group and conservative treatment group. Conclusion Arthroscopic treatment of posterior curiae ligament rupture is more effective than conservative treatment, especially in the treatment of joint stability and so on.

Physiological and biochemical change of Paris seed in after-ripening during variable temperature stratification / 中国中药杂志

In order to explore the dormancy physiological and biochemical mechanism of Paris seeds, the seed embryo growth courses, and the dynamic change of 5 enzymes, include SOD, POD, CAT, MDH, G-6-PDH were measured during variable temperature stratification. The results indicated that Paris seeds embryo grew quickly after 40 d in warm-stratification (18 ± 1) °C, at the meantime the metabolic activity was significantly strengthened. These facts showed that Paris seeds turned into physiological after-ripening process. After 60-80 d, the morphological embryo after-ripping process basically completed, and the following cold-stratification (4 ± 1) °C furthered Paris seed to finish physiological after-ripening. After 40 d, the activity of MDH decreased while G-6-PDH increased significantly. This showed that the main respiratory pathway of seed changed from TCA to PPP, which benifited breaking seed dormancy. In the whole period of stratification process, the activity variation of SOD and CAT was insignificantly and the activity of POD was enhanced significantly after shifting the seed in cold stratification process. This showed that SOD, CAT had no direct effects on breaking Paris seed dormancy but keeping the seed vigor, while the POD might involve in the process of Paris seed dormancy breaking.

Di-(2-ethylhexyl) phthalate activates the apoptosis Caspase pathway in rat Leydig cells in vitro / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the effects of di-(2-ethylhexyl) phthalate (DEHP) on the expressions of Caspase-3 and Caspase-9 genes in rat Leydig cells and the apoptosis of the cells in vitro.</p><p><b>METHODS</b>Leydig cells were isolated from male SD rats, primarily cultured and treated with DEHP at a low (10 nmol/L), a medium (50 nmol/L) and a high dose (100 nmol/L) for 24 hours. Then the mRNA expressions of Caspase-3 and Caspase-9 genes in the Leydig cells were detected by real time PCR, their protein expressions determined by Western blot, and the apoptosis of the Leydig cells measured by flow cytometry.</p><p><b>RESULTS</b>Compared with the DMSO control group, the low-, medium- and high-dose DEHP groups showed significantly upregulated expressions of Caspase-3 mRNA (1.69 +/- 0.38 vs 3.82 +/- 0.39, 6.91 +/- 0.40 and 15.47 +/- 0.40, P < 0.05), Caspase-3 protein (0.18 +/- 0.0.09 vs 0.32 +/- 0.10, 0.61 +/- 0.08 and 0.89 +/- 0.09, P < 0.05), Caspase-9 mRNA (2.24 +/- 0.41 vs 5.16 +/- 0.43, 9.61 +/- 0.45 and 19.22 +/- 0.43, P < 0.05) and Caspase-9 protein (0.26 +/- 0.07 vs 0.40 +/- 0.08, 0.68 +/- 0.09 and 0.96 +/- 0.08, P < 0.05), as well as increased apoptosis rate of Leydig cells (4.36 +/- 1.11 vs 7.52 +/- 1.09, 12.72 +/- 1.10 and 24.59 +/- 1.11, P < 0.05), all in a dose-dependent manner.</p><p><b>CONCLUSION</b>DEHP can induce the apoptosis of rat Leydig cells by activating the apoptosis Caspase pathway, and consequently affect the function of Leydig cells.</p>

Decreased levels of pNR1 S897 protein in the cortex of neonatal Sprague Dawley rats with hypoxic-ischemic or NMDA-induced brain damage

Our objective was to investigate the protein level of phosphorylated N-methyl-D-aspartate (NMDA) receptor-1 at serine 897 (pNR1 S897) in both NMDA-induced brain damage and hypoxic-ischemic brain damage (HIBD), and to obtain further evidence that HIBD in the cortex is related to NMDA toxicity due to a change of the pNR1 S897 protein level. At postnatal day 7, male and female Sprague Dawley rats (13.12 ± 0.34 g) were randomly divided into normal control, phosphate-buffered saline (PBS) cerebral microinjection, HIBD, and NMDA cerebral microinjection groups. Immunofluorescence and Western blot (N = 10 rats per group) were used to examine the protein level of pNR1 S897. Immunofluorescence showed that control and PBS groups exhibited significant neuronal cytoplasmic staining for pNR1 S897 in the cortex. Both HIBD and NMDA-induced brain damage markedly decreased pNR1 S897 staining in the ipsilateral cortex, but not in the contralateral cortex. Western blot analysis showed that at 2 and 24 h after HIBD, the protein level of pNR1 S897 was not affected in the contralateral cortex (P > 0.05), whereas it was reduced in the ipsilateral cortex (P < 0.05). At 2 h after NMDA injection, the protein level of pNR1 S897 in the contralateral cortex was also not affected (P > 0.05). The levels in the ipsilateral cortex were decreased, but the change was not significant (P > 0.05). The similar reduction in the protein level of pNR1 S897 following both HIBD and NMDA-induced brain damage suggests that HIBD is to some extent related to NMDA toxicity possibly through NR1 phosphorylation of serine 897.

mRNA expression levels of p53 and DNA damage and repair genes in peripheral blood lymphocytes of benzene-exposed workers / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the relationship between the mRNA expression levels of p53-mediating DNA damage and repair genes in the peripheral blood lymphocytes of workers and their exposures to benzene in their working environment.</p><p><b>METHODS</b>The mRNA expression levels of p53 and related genes were determined by SYBR Green I chimeric fluorescence quantitative real-time RT-PCR analysis in peripheral blood lymphocytes of 72 workers, who were classified into group A (46 direct exposure to benzene) and group B (26 indirect exposure to benzene) based on their positions, and 29 controls. The differences of gene expression levels were analyzed by software REST 2005. Meanwhile, the peripheral blood leukocytes, hemoglobin and platelet of workers and controls were counted. Benzene content was measured in the samples of toluene, used as raw material, and spraying agents and benzene, toluene and xylene concentrations in the air of workplaces were monitored.</p><p><b>RESULTS</b>There were no significant differences in the mRNA expression levels of p53, Ku80, Ape1 and Mdm-2 between group A or group B and control group (P > 0.05). The expression up-regulation of p21 mRNA was found, but without significant difference (P > 0.05). However, the mRNA expression levels of Rad51, Bcl-2, Bax, Xpa and Xpc in group A and Rad51 in group B were downregulated significantly (P < 0.05 or P < 0.01). Moreover, both the counts of white blood cell, hemoglobin and platelet in group A were (4.93 +/- 1.27) x 10(9)/L, (123.97 +/- 11.80) g/L and (124.02 +/- 41.22) x 10(9)/L respectively and platelet in group B (135.80 +/- 39.44) x 10(9)/L were significantly lower than in control group (P < 0.05 or P < 0.01).</p><p><b>CONCLUSION</b>The mRNA expression levels of some p53-mediating DNA damage and repair genes are downregulated in the workers chronically exposed to low benzene concentration. The working environment impacts on health of group A workers are greater than the ones of group B.</p>

Quantitative detection of hepatitis B virus covalently closed circular DNA in sera of chronic hepatitis B patients with a newly established assay / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To quantitatively detect hepatitis B virus covalently closed circular DNA (HBV cccDNA) in sera of chronic hepatitis B patients with a newly established assay.</p><p><b>METHODS</b>Primers and probe were designed in highly conservative region of HBV DNA. DNA was extracted from 175 sera samples of chronic hepatitis B patients, and was treated with plasmid-Safe-ATP-dependent Dnase(PSAD) to eliminate the relaxed circular DNA (rcDNA). The products were amplified by real-time PCR with primers spanning.</p><p><b>RESULTS</b>The detection rate of serum HBV cccDNA was found to correlate directly with serum HBV DNA loading. HBeAg positive chronic hepatitis B patients had higher serum HBV cccDNA levels than HBeAg negative chronic hepatitis B patients.</p><p><b>CONCLUSION</b>The method is good because of the high specificity. It can be used for detection of HBV cccDNA. DNA;</p>

Multiple-site analysis of HBV drug-resistant mutations in 340 patients with chronic hepatitis B / 中华肝脏病杂志

<p><b>OBJECTIVES</b>To analyze HBV drug-resistant mutations against nucleos(t)ide analogues at 12 reported sites in 340 patients with chronic hepatitis B.</p><p><b>METHODS</b>Serum HBV DNA was extracted and a nested PCR assay was employed for the reverse transcriptase (RT) gene amplification. Direct sequencing of PCR product was performed. The significance of detected mutations was analyzed in view of clinical data of the patients.</p><p><b>RESULTS</b>Drug-resistant mutations were detected in 68 patients taking lamivudine (LAM), 10 taking adefovir (ADV), 8 taking entecavir, and 1 taking telbivudine (LdT). M204V and M204I were the most common LAM-resistant mutations. The former usually emerged with L180M while the latter often emerged alone. N236T +/- A181 substitution was the most frequently seen ADV-resistant mutation. ETV-resistant mutations occurred on the basis of LAM-resistant mutations and T184 change was the most common form. LdT-resistance was observed as M204I. Interestingly, these drug-resistant mutations were detected in a few patients who had not been treated with nucleos(t)ide analogues.</p><p><b>CONCLUSION</b>Detection of HBV drug-resistant mutations at multiple sites of the viral RT gene is valuable for discovering and verifying drug resistance and thus is very helpful in planning anti-HBV therapy.</p>

Concise translation of TCM terminologies and its application / 中国中西医结合杂志

TCM terminologies are the professional medical terms, marked by in Chinese features of simplification and cogency, as well as rich connotations, and thus conciseness should be one of the main principles when it comes to their translation. The concise translation and its application were discussed in this paper through semantic and logic analysis on TCM terms and starting with the English word-building.

Comparisons of imageology in postoperative cervical lymph node metastasis of thyroid carcinoma / 上海第二医科大学学报

Objective To explore the clinical manifestations of ultrasonography(US),99mTc-methoxyisobutylisonitrile(99mTc-MIBI),and 131I whole body scan(131I-WBS)of patients with differentiated thyroid carcinoma(DTC)and cervical lymph node metastasis.Methods A total of 117 cases received examinations of US and 99mTc-MIBI before uses of 131I and received 131I-WBS after 6 d of 131I treatment.Combined with serum thyroglobulin(Tg),131I-SPECT/CT,lymph node biopsy and clinical follow-up of patients,cervical lymph node metastases were identified.Results In 117 patients,the sensitivity of US,99mTc-MIBI and 131I-WBS were 76.5%,67.1% and 83.5%(P

Effect of ingredients of Astragalus-Salvia compound on vascular endothelial cell in placenta and vascular endothelial growth factor mRNA expression in trophocyte in pregnant rats with inhibited nitric oxide synthesis / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To investigate the molecular mechanisms of effective ingredients of Astragalus-Salvia compound (ASC) in increasing placental blood supply, to provide thought for establishing an effective prevention and treatment of insufficient placental blood supply caused complications of pregnancy.</p><p><b>METHODS</b>The effective ingredients of ASC was isolated and abstracted and the rat model of inhibited nitric oxide synthesis was established by using L-Arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor. The mRNA expression of vascular endothelial growth factor (VEGF) in placental trophocyte and primordial micrangial endothelial cell was determined by using in situ hybridization at 12th day of pregnancy.</p><p><b>RESULTS</b>The VEGF mRNA expression was significantly lower in nitric oxide synthesis inhibited model rats than that in rats non-modeled, or in model rats treated by ASC abstracts or nitroglycerin (P < 0.05, P < 0.01).</p><p><b>CONCLUSION</b>Effective ingredients of ASC may improve VEGF mRNA expression in placental trophocyte and vascular endothelial cell in early pregnancy, and thus be favorable for placental vascular net formation, trophocyte infiltration and mother-placental circulation constitution for increasing placental blood supply to prevent and treat the insufficient placental blood supply caused diseases such as pregnancy-induced hypertension syndrome.</p>

Establishing a simple method for detecting tinnitus of rats by using behavioral response of conditioned escape / 中国应用生理学杂志

<p><b>AIM</b>To create a simple behavioral procedure for detecting tinnitus of rats.</p><p><b>METHODS</b>A procedure based on a Pavlovian-conditioned suppression paradigm was set referencing Jastreboff's way to detect tinnitus behaviorally in conscious animals. Rats received acquisition training through Pavlovian conditioning to associate the conditioned stimulus (noise offset) with the unavoidable unconditioned stimulus (foot-shock). The manifestation here is escape reaction. An extinction procedure followed, during which the subject was exposed to the conditioned stimulus, but shock is no longer given. The manifestations of the rats in different group during the extinction processes were observed. Tinnitus was induced by salicylate (SA) injection to validate the method.</p><p><b>RESULTS</b>The escaped rate of SA group is lower than that of the control. It indicated that the SA rats escaped seldom when there was a sound off, because the rats might perceive the salicylate-induced auditory sensation as a substitute for the background noise that had acquired a safety value during training.</p><p><b>CONCLUSION</b>The behavioral procedure could be used to detect tinnitus of rats induced by salicylate.</p>