Objective To develop an ultra performance liquid chromatography(UPLC)method for simultaneous determination of 19 amino acids in rat serum by employing the pre-column derivatization of phenyl isothiocyanate(PITC),verify and preliminarily apply the method.Methods The analysis was performed on an ACQUITY UPLC~?BEH C_(18) column(2.1mm×100 mm,1.7 μm) by using 0.1 mol/L sodium acetate buffer solution-acetonitrile as mobile phase at the flow rate of 0.3 mL/min in gradient elution.The column temperature was fixed at 52 ℃,and the detection wavelength was 254 nm.The specificity,linearity,precision,stability and accuracy of the method were verified based on the optimized chromatographic conditions and preparation method of sample solution,and the contents of 19 amino acids in rat serum were determined by using the developed method.Results All 19 amino acids in rat serum were separated well within 10 min,and the blank derivatization solvent and internal standard compounds had no interference with the analysis of amino acids.All the components exhibited good linear correlation in the given range(r ≥ 0.998 0),the limit of detection was 0.004 6-0.186 5 μg/mL,and the limit of quantitation was 0.013 9-0.559 6 μg/mL.The RSDs of precision and stability tests were all less than 4%.The average spike recoveries ranged from 90% to 110% and the RSDs were less than 5%.The contents of amino acids in rat serum ranged from 4.837 to 110.233 μg/mL.Conclusion The developed method is sensitive,simple and feasible,which is suitable for the analysis of amino acids in rat serum.

Objective To investigate the effect of uterine cavity injection of absolute ethanol on estrous cycle in mice.Methods Twenty mice with regular estrous cycle were selected by vaginal exfoliated cells staining, and then were injected absolute ethanol into their uterine cavity.The estrous cycle was observed and recorded every day.Ten mice were selected randomly to observe the changes of second estrous cycle every two hours.Results After the injection of absolute ethanol into the uterine cavity of the experimental mice, the estrous cycle was greatly prolonged, and the various degree of disorder was observed in estrus and pre-estrus.Conclusions The disorder was observed in estrous cycle of mice after the injection of absolute ethanol, which maybe provides some references for clinical use of absolute ethanol.

Objective This study was designed to explore the therapeutic effect of psoralen on type Ⅱ collagen-induced rheumatoid arthritis in mice and its molecular mechanism.Methods DBA/1J mice were immunized with type II bovine collagen to induce rheumatoid arthritis.The model mice were randomly divided into Psoralen group(PSO),methotrexate group(MTX) and model group(Vehicle).Clinical signs of arthritis in the mice were monitored.The spleen index was assessed.Splenic Th1 and Th2 cells were counted by flow cytometry.ELISA was used to detect the levels of inflammation-associated factors TNF-α,IL-6 and IL-1β in the serum.Results Compared with the vehicle group,the ankle swelling and limitation of joint activity in the PSO group were significantly reduced,the spleen index and Th1 cell percentage were significantly decreased,and the Th2 cell percentage showed no significant change in the PSO group.Expression of TNF-α,IL-6 and IL-1β in serum was notably decreased in the PSO group.All the indexes showed no significant difference between the PSO and MTX groups.Conclusions Psoralen may attenuate the severity of type II collagen-induced rheumatoid arthritis in mice by regulating the balance of Th1/Th2 cells and inhibiting the expression of TNF-α,IL-6 and IL-1β.

Chinese hamster is an important laboratory animal in medical and biological researches,but the molecular genetic markers research was rarely reported.In our study the base composition,gene structure,genetic evolution and other characteristics of mitochondrial genome of Chinese hamster were analyzed using the methods of bioinformatics and comparative genomics,genetic quality detection system of Chinese hamster were also established.These results would supply genome data for animal models of human diseases,and lay the foundation for scientific evaluation and reasonable utilization.

Objective To study the expression and significance of apoptosis-related genes caspase-3,caspase-9,Bax and Bcl-2 in oral normal mucosa,oral simple hyperplasia,oral epithelial dysplasia and oral squamous cell carcinomas (OSCC) in Chinese hamsters.Methods The expressions of mRNA and protein of caspase-3,caspase-9,Bax and Bcl-2 in the oral normal mucosa,oral simple hyperplasia,oral epithelial dysplasia and OSCC tissues in Chinese hamsters were examined by immunohistochemistry and RT-PCR.Results During the process of oral carcinogenesis,the expression of Bcl-2 protein was significantly higher in OSCC than in oral normal mucosa,oral simple hyperplasia,and oral epithelial dysplasia (P<0.05).In dysplastic epithelia,the protein expressions of caspase-3,caspase-9 and Bax were more than that of normal epithelia,and along with the increased dysplasis,the expression level was decreased.Further analysis showed that expression of Bcl-2 was negatively related with the expressions of Bax,caspase-3 and caspase-9 (P<0.05).The result of RT-PCR showed that Bcl-2 was significantly increased in OSCC compared with normal mucosa,while the expressions of caspase-3,caspase-9 and Bax were decreased (P<0.05).Conclusions In the Chinese hamster squamous carcinoma,the expressions of caspase-3,caspase-9 and Bax are reduced and the Bcl-2 expression are increased,indicating that the expressions of caspase-3,caspase-9,Bax and Bcl-2 are closely related with the occurrence and development of oral squamous cell cancinoma.This study can offer some clues for gene therapy of OSCC,or can provide a reference for evaluating the biological characteristics and prognosis of OSCC.

Objective To observe and analyze functional areas of the cerebral cortex in C57BL/6 mice of various ages.Methods Improved alkaline phosphatase staining was used to reveal the microvascular morphology of the cerebral cortex in C57BL/6 mice,including the motor cortex(primary and secondary motor cortex),sensory cortex(primary and secondary somatosensory cortex),visual cortex(primary and secondary visual cortex),and auditory cortex(primary and secondary auditory cortex),olfactory cortex(extrarhinal and entorhinal cortex).Images were captured under an OLYMPUS BX51 microscope with Image-Pro Plus 5.1 software.The microvascular length density(Lv),microvascular surface area density(Sv),and microvascular volume density(Vv)were analyzed by Image-Pro Plus 5.1 software.Results Expression of alkaline phosphatase was abundant in cerebral cortical microvessels of adult and elderly mice,and slightly expressed in juvenile mice,but not in lactating mice.Pial blood vessels enter the cortex in T shape,Y shape,large arc,and small arc four manners.Lv,Sv and Vv in different parts of the same aged mice showed a decreasing trend in motor,sensory,visual,auditory and olfactory cortexes,and the microvascular density of Lv,Sv and Vv in motor and sensory cortexes was statistically significant compared with the olfactory cortex(P<0.05).The vascular density in all functional areas in elderly mice was lower than that in adult mice,but no statistical significance was found(P>0.05).Conclusions The expression of alkaline phosphatase in microvessels in functional areas of the cerebral cortex in C57BL/6 mice increases with age and reached its peak value in adulthood.The microvascular architecture in the brain provides morphological parameters to establish cerebrovascular disease models.

Objective To investigate the effect of Liensinine on lipopolysaccharide ( LPS)-induced acute lung injury (ALI) in mice. Methods BALB/c mice were randomly divided into six group: control group, LPS group, LPS+Liensinine (2 mg/kg, 4 mg/kg, 8 mg/kg) groups, and dexamethasone group. Acute lung injury in mice was induced by nasal instillation of LPS. After 12 h, the pathological changes of lung tissue were observed. The levels of TNF-α, IL-6 and IL-1β in bronchoalveolar lavage fluid (BALF) were detected by ELISA. The number of neutrophils in BALF was detected using Wright-Giemsa staining. Total protein content was detected by BCA protein quantification assay. The pulmonary capillary permeability was examined with Evans blue. The MPO activity, MDA content, SOD activity, and GSH content in lung homogenate supernatant were detected by spectrophotometry. The content of ROS in lung tissue was detected by flow cytometry. Results The LPS group showed inflammatory cell infiltration, thickening of bronchial alveolar wall and pulmonary congestion in the lung tissue, while Liensinine improved the lung injury. In the LPS group, the contents of TNF- α, IL-6 and IL-1β in BALF were significantly increased, the number of neutrophils and the content of total protein were significantly increased, pulmonary capillary permeability, MPO activity and MDA content were increased, SOD activity and GSH content were decreased, the content of ROS was increased; while the Liensinine group reduced the contents of TNF-α, IL-6, IL-1β in BALF, reduced the number of neutrophils and total protein content, decreased the pulmonary capillary permeability, attenuated MPO activity and MDA contents and increased SOD activity and GSH content, and reduced ROS content in the LPS-challenged lung tissue. Conclusions Liensinine protects mice from LPS-induced acute lung injury by its anti-inflammatory and anti-oxidative activities.

Objective:To explore the metabolic basis and related molecular mechanism of oral squamous cell carcinoma(OSCC)path-ogenesis.Methods:20 Chinese hamsters were divided into 2 groups(n=10).OSCC models were induced by dimethylbenzanthracene(DMBA)in 10 of the animals and the other 10 were used as the controls.LC-MS chromatography-mass spectrometry was used to iden-tify the metabolites in the buccal pouch,and multidimensional statistical analysis of the metabolites was performed with the orthogonal partial least squares discriminant analysis model.Variable Importance for the Projection(VIP)＞1 and P＜0.05 were used as the criteria to screen the differential metabolites between the 2 groups.KEGG pathway annotation and enrichment analysis for the metabolites were performed to screen the significantly differential pathways.Results:The hamster cheek pouches painted with 0.5％DMBA for 18 weeks were diffused with leukoplakia and loaded obvious papillary protrusions,which were diagnosed as OSCC by pathological examination.Lipids and lipid-like molecules were the main differential metabolites.Reprogramming of unsaturated fatty acid biosynthesis,cholesterol accumulation,enhanced catabolism of tryptophan,up-regulation of aspartate,increased synthesis of pyrimidine and purine,etc.were important metabolic features in the occurrence and development of OSCC.Conclusion:Molecular intervention targeting the related met-abolic pathways is expected to inhibit OSCC pathogenesis and progression.

Objective To determine the blood physiological and biochemical indexes in the inbred SHANXI MU strain of spontaneous type 2 diabetes(T2DM)Chinese hamsters.Methods Chinese hamsters with spontaneously developed T2DM and normal hamsters(n=10 hamsters per group),aged 12 months,were selected for the study.Fasting blood samples were collected and 15 physiological parameters and 16 biochemical indicators were analyzed using a Sysmex XT automated hematology analyzer and Hitachi fully automatic biochemical analyzer.Results The white cell count,red cell count,platelet count,hemoglobin level,alanine transaminase,aspartate transaminase,glutamate,total cholesterol,triglycerides,and uric acid all differed significantly between the diabetic and control groups(P＜0.05).Conclusions The change of blood physiological and biochemical indexes in the Chinese hamster spontaneous T2DM model were in line with the trend in human T2DM incidence,thus providing basic data for the application of this model.