Abstract:Objective To study the mutations of Env sequence of SIVmac239 after infection of Chinese rhesus monkeys, and compare the differences and characteristics of Gp120 sequences of enterotropic and neurotropic SIV strains. Methods Six strains of simian immunodeficiency virus were analyzed in this study: four separated from peripheral blood mononuclear cells of SIVmac239-infected monkeys and two neurotropic SIVmac251 strains. Isolated and cultured monoclonal virus was obtained by limiting dilution assay. Gp120 sequences were amplified after the RNA extraction and phylogenetic analysis was processed thereafter. So did the Gp120 amino acid sequence and N-glycosylation sites analysis of the enterotropic and neurotropic strains. Results SIVmac239 had different mutations in four rhesus monkeys. The diversity in amino acid sequences of the enterotropic and neurotropic strains concentrated in the V1 and V4 regions of Gp120. The enterotropic strains had an addition of glycosylation site in V4 but the glycosylation site changes of neurotropic strains were located in the conservative regions of C1, C2 and C3. Conclusions The addition of one glycosylation site in V4 region of GP120 and loss of one glycosylation site in C1 region are associated with enhanced enterotropism and neurotropism. The differences between the enterotropic and neurotropic strains are not dipicted in Gp120 V3 region which is closely related with the tropism of strains.

Abstract:Objective To observe the apoptotic effect of cardamonin on K562 cells and its relationship with the expressions of PTEN, p-Akt, NF-κB and Bcl-2. Methods K562 cells were treated with cardamonin for 48 h, and the following tests were performed: (1) The cell morphology was observed by light microscopy.(2)IC50 of the K562 cells was dtermined by MTT test.(3)The apoptosis rate was detected by flow cytometry. (4) The expressions of Bcl-2 and Bax mRNA were detected a by RT-PCR. (5) The expressions of PTEN, p-Akt, NF-κB and Bcl-2 proteins were detected by Western blot. Results Obvious apoptosis was observed in the K562 cells after treated with cardamonin for 48 h. MTT assay indicated that the proliferation of K562 cells was obviously inhibited in a dose-and time-dependent manner. Comparing with the blank group, the early apoptosis rate and expression of Bax mRNA were significantly increased. At the same time, the expression of Bcl-2 mRNA was significantly decreased. All of them presented a dose-dependent manner. The expression of PTEN obviously increased with the increasing dose of cardamonin and the expressions of p-Akt, NF-κB and Bcl-2 were decreased. Conclusions Cardamonin promotes the apoptosis in K562 cells in a dose-dependent manner by increasing the expression of PTEN and decreasing the expressions of p-Akt, NF-κB, and Bcl-2.

Abstract:Objective To evaluate the use safety of a unitary package peracetic acid (PAA) disinfectant through acute and subacute toxicity experiments in rats. Methods This study was conducted according to the Technical Standard For disinfection (Version 2002). In the acute toxicity experiment, 60 healthy Wistar rats were randomly divided into different groups of PAA given by single intragastric gavage. Symptoms of poisoning of the animals were observed to calculate the half lethal dose (LD₅₀).In the subacute toxicity experiment, 40 healthy Wistar rats were randomly divided into three dose groups and negative control group. The rats were given 33-342 mg/kg BW PAA for 28 days. At the end of test, the body weight, the organ-to-body weight ratio and the hematological and biochemical indices were determined, and pathological examination was performed. Results The acute oral LD₅₀ of female rats was 1470 mg/kg BW, and the LD₅₀ of male rats was 1710 mg/kg bw. The results of subacute toxicity test showed that the body weight, the organ-to-body weight ratio and the hematological and biochemical indices had no significant difference between the dose groups and control group. No obvious abnormality was observed in gross anatomy and histopathological examination. Conclusions The results of the acute toxicity test prove that PAA has a low toxicity level, and no significant subacute toxicity was observed at the exposure doses.

Abstract:Objective Type 2 diabetes mellitus (T2DM) as a common disease around the world becomes a great threat to the health of human beings. The cynomolgus T2DM model, which preferably simulates human T2DM onset and progress, can be beneficial to the drug development and clinical treatment. In the present study, 37 of T2DM-susceptibility SNPs and the extended genome sequences were used to obtain corresponding SNPs in the T2DM cynomolgus monkeys. Methods Firstly, DNA pool screening was conducted. Then, using polymerase chain reaction to amplify and to sequence the cynomolgus homologous sequences. Using DNAStar software to analyze the differences between bases. Finally, we used analysis of variance and F test to calculate the frequency of alleles. We also used the GLM models of SAS software to analyze the association of genotype with fasting plasma glucose and glycosylated hemoglobin. Results SNP661A, SNP661B, SNP343A, SNP343B, SNP343C, SNP565A, SNP565B and SNP565C were found to have a significant difference of allele frequencies between spontaneous cases and controls. Conclusions The findings of this study suggest that SNP661A, SNP661B, SNP343A, SNP343B and SNP343C may play an important role in the establishment of cynomolgus T2DM models.

Abstract:Objective To study the effects of different hypertonic saline (4.5% and 7.5%) in fluid resuscitation on hemodynamics in traumatic rabbits with hemorrhagic shock. Methods Thirty-two healthy rabbits (male or female, 2.0-3.0 kg body weight) were divided into 4 groups randomly: SHAM group, SWT group (shock without treatment), 4.5% group (resuscitation with 4.5% hypertonic saline), and 7.5% group (resuscitation with 7.5% hypertonic saline), 8 rabbits in each group. The rabbit model of uncontrolled hemorrhagic shock was established after anesthesia. The fluid used in the two methods of fluid resuscitation was infused into the rabbits at designed times. The hemodynamic data including the left intraventricular systolic pressure (LVSP) and maximal change rate of left intraventricular pressure (±dp/dtmax) were determined at 0 min, 30 min, 60 min, and 90 min. Results (1) The rabbit models of uncontrolled hemorrhagic shock were generated successfully. At 30 min, data of SWT in the 4.5% and 7.5% groups had no significant difference through pairwise comparison (P>0.05). (2) The hemodynamic parameters changed similarly during the experiment. At 60 min, the values of the 7.5% group (LVSP=115.00±8.37 mmHg, +dp/dtmax=4.29±0.50 mmHg/ms, -dp/dtmax=-3.25±0.25 mmHg/ms) were significantly higher than those in the 4.5% group ((LVSP=104.14±7.73 mmHg, +dp/dtmax=3.35±0.39 mmHg/ms, -dp/dtmax=-2.27±0.12 mmHg/ms) (P<0.05). At 90 min, the data of the 7.5% group were higher, but statistically not significantly different (P>0.05). Conclusions Fluid resuscitation can improve the hemodynamic function in traumatic rabbits with uncontrolled hemorrhagic shock. Comparing with the 4.5% hypertonic saline, 7.5% hypertonic saline can improve the hemodynamic function more apparently. Our results may provide an experimental support for the treatment of clinical patients with uncontrolled hemorrhagic shock.

Abstract:Objective To explore the influence of drug dosage, solvent and other main influencing factors on the successful establishment of alloxan-induced hyperglycemia mouse model and the effect on the stability of this model. Methods 160 6-8-week-old Kunming mice ofSPF grade, (male:female=1:1) were used in this study. The influences of different dosages of alloxan and solvent combinations on the successful establishment rate of the model, survival rate, body weight, fasting blood glucose, blood glucose area under curve, serum insulin level and their stabilities were dynamically observed for six weeks. Results By single intraperitoneal injection of 160 mg/kg bw alloxan (pH 4.5 citrate sodium as solvent), we were able to obtain a stable experimental hyperglycemic mouse model with higher levels of successful establishment rate (70%), survival rate (75%), fasting blood glucose (15-20 mmol/L), glucose area under the curve (55-65 mmol/L) and a lower but not loss of serum insulin levels (21 mIU/L). Conclusions In the present study we have carefully considered the influence of main factors such as drug dosages, solvent, etc., on the alloxan-induced experimental hyperglycemic mouse model, and successfully established this model after 6-week period observation of its stability. This model may provide a useful tool in the research of experimental diabetes and hypoglycemic functional studies.

Abstract:Objective To establish a guinea pig model for diagnostic reagent of tuberculosis. Methods By single or multiple subcutaneous injection of heat-killed H₃₇Rv in different doses in the groin of guinea pigs to establish a model of positive response to 0.1 mL (5 IU) standard tuberculin (TB-PPD) skin test. Results Three doses of heat-killed H₃₇Rv (0.2 mg/mL,0.3 mg/mL and 0.5 mg/mL) could be used to generate the model of biological diagnosis of tuberculosis. After 24 and 48 hours, the diameter of red spot by TB-PPD skin test was 15.4±2.3 mm when a dose of 0.2 mg/mL heat-killed H₃₇Rv was administered for immunizing and allergizing the guinea pigs. The biggest red spot was induced at doses of 0.3 mg/mL and 0.5 mg/mL. The test results showed that the immune response induced by multiple njection to immunizing and allergizing guinea pigs was not significantly different than that induced by single immunizing injection, and the first skin test was better than the second, third and fourth skin test (P≤0.05). In addition, the body weight of the guinea pigs was still increasing after infection with heat-killed H₃₇Rv, and ulcers occurred in the injection sites in some guinea pigs. Conclusions A single subcutaneous injection of 0.2 mg/mL heat-killed H₃₇Rv in guinea pigs can be used well to establish a reliable model for biological diagnostic reagent of tuberculosis. Increasing the sensitizing dose and multiple sensitization can not increase the intensity of the delayed-type hypersensitivity (DTH) response.

Abstract:Objective To study the cholesterol nuclear-cytoplasmic interaction effect and position cholesterol traits QTL in mice. Methods Improving the nuclear-cytoplasmic interaction models and methods that have been constructed, and analyzing the public database of total cholesterol and lipoprotein data of F2 group that derived from DBA/2J (D2) and CAST/EiJ (CAST) mice. Results Six QTL that controlling total cholesterol, HDL and nonHDL were located in 4 linkage groups in the genome. In the models constructed in this study, we found a QTL has significant interaction with cytoplasmic background, which changes the previous results of data analysis, the genetic mouse cholesterol and lipoprotein components opened up new ideas. Conclusion Mouse cholesterol trait is the result of interaction of nuclear genes and cytoplasmic background.

Abstract:Objective To study the effects of dammarane sapogenins (DS-1226) on sleep interruption-induced learning and memory impairment in mice. Methods 130 SPF healthy 5-6-week old male ICR mice were randomly divided into control, model, DS-1226 low dose, DS-1226 medium dose and DS-1226 high dose groups. The behavioral alterations in open field (OF), Morris water maze (MWM) and step-through (ST) tests were detected at 15 days after rotating drum-induced sleep interruption (SI). Results The total distance, movement speed, total duration of movement were increased in OF test (P<0.05, vs. the model group) after treatment. The latency of place navigation was increased from day 5 in the MWM test after 15 d sleep interruption, and the number of crossing in the target quadrant and the percent distance in target quadrant were decreased after 15 d sleep interruption (P<0.05, vs. the control group), while the latency of place navigation was decreased, and the percent distance in target quadrant and percent time in target quadrant after high dose DS-1226 oral administration (P<0.05, vs. the model group) were increased. Error times, distance in dark chamber, time in dark chamber and immobility time in dark chamber were increased in training of step through test (P<0.05, vs. the control group); while these indexes were decreased after DS-1226 oral administration (P<0.05, vs. the model group). But there was no significant difference in the step through testing course. Conclusions The results show that orally administrated DS-1226 can ameliorate SI-induced learning and memory impairment, and there is a significant dosage-effect relationship.

Abstract:Objective To study the effect of dopamine receptors on neurological and physiological activities. Methods Dopamine D1 receptor gene (DRD1) knockout mice and dopamine D3 receptor (DRD3) gene knockout mice were introduced, and double gene knockout mice were bred in our lab. Seven SPF male mice in each group were used in this experiment. The food intake, water intake, body weight gain for 24 hours were tested on the age of 30 d, 50 d, and 70 d and were compared with those of wild type mice. Results DRD1 gene and DRD3 gene showed significant effect on the body weight in mice in age of 21 day and 35 day, but at the age of 90 day, the differences became insignificant among the mice of various genetypes. Conclusions Dopamine may effect on the foraging and satiety in newborn mice through regulating the hypothalamic-pituitary-adrenal (HPA) axis activity, and finally leads to a reduced body weight gain in newborn mice and puppies during lactation. Furthermore, DRD1 gene and DRD3 gene may influence on body weight of newborn mice through regulating mothers' lactation, lead to a lower body weight at ablactation, and compensatory increase of body weight after ablactation. Our results provide a substantial foundation for studying the function and interaction of DRD1 and DRD3 genes.

Abstract:Objective To observe the effects of resveratrol on blood pressure and cardiac function in the rats with vascular calcification induced by vitamin D₃ plus nicotine. Methods 32 male SD rats were randomly divided into the following groups for treatment: Control (Con), calcified (Cal), Cal+Res low dose [L] and Cal+Res high dose [H] groups. Blood pressure, cardiac function, alkaline phosphatase (ALP) activity in serum or aorta were detected and HE staining was used for pathological examination at 6 weeks after treatment. Results Compared with the Con group, LVW/BW, heart rate, systolic aortic pressure, pulse pressure, mean blood pressure, left ventricular systolic pressure and ALP activity in serum or aorta of rats in the Cal group were increased by 27.3%, 8.8%, 22.8%, 47.5%, 13.6%, 19.0%, 280% and 265% (P<0.05 or P<0.01), respectively. Compared with the Cal group, pulse pressure and ALP activity in serum or aorta of rats in the Cal+Res [L] group were decreased by 8.5%, 34.5% and 29.5% (P<0.05 or P<0.01), respectively, and LVW/BW, systolic aortic pressure, pulse pressure, mean blood pressure, left ventricular systolic pressure and ALP activity in serum or aorta of rats in the Cal+Res [H] group were decreased by 14.2%, 13.6%, 23.7%,10.0%, 9.0%, 53.1% and 45.9% (P<0.05 or P<0.01), respectively. Compared with the Cal+Res [L] group, systolic aortic pressure, pulse pressure, left ventricular systolic pressure and ALP activity in serum or aorta of rats in the Cal+Res [H] group were decreased by 8.3%, 16.7%, 5.8%, 28.4% and 23.2% (P<0.05 or P<0.01), respectively. Compared with the aorta in the Con group, pathological examination revealed thickened vessel walls and disordered elastic fibers in the calcified aortas. However, the thickness of aortic wall in the Cal+Res [L] and Cal+Res [H] groups was reduced and elastic fibers were regularly arranged. Conclusion Resveratrol can effectively reduce the blood pressure and improve the cardiac function in rats with vascular calcification.

Abstract:Objective To explore the influence of tetrahydroxystilbene glucoside (TSG) on the neuron proliferation in epileptic rats and the related mechanisms. Methods 54 healthy SD male rats were randomly divided into three groups: sham-operated group, epilepsy group and epilepsy with TSG treatment group. The epilepsy group was established by stereotactic brain trace injection with kainic acid (KA). TSG solution (3 mg/kg) was injected intraperitoneally at 6 hours after the epilepsy group established, and then q.d. for consecutive 42 days. The sham-operated group and epilepsy group were injected with normal saline. The influence of TSG on cell proliferation of rat hippocampal dentate gyrus BrdU-positive granular cells was observed by immunohistochemistry. Results Compare with the epilepsy group, the amount of glial fibrillary acid protein (GFAP)-positive astrocytes was significantly reduced and dentate gyrus BrdU-positive cells were significantly increased in the TSG group (P<0.01). Conclusions Tetrahydroxystilbene glucoside (TSG) promotes neurogenesis of neural stem cells and neurons, and inhibits the growth of hippocampal dentate gyrus astrocytes in epilepsy rats.

Abstract:Objective To explore the relationship between mechanical withdrawal threshold (MWTs) and local cutaneous blood perfusion (BP) in rats with acute inflammation induced by carrageenan. Methods Twenty male Sprague-Dawley (SD) rats were randomly divided into control and model groups. The acute inflammatory rat model was established by subcutaneously injecting with carrageenan into the left hindpaw. MWTs were measured by Dynamic Plantar Aesthesiometer 37450 before injection (as base) of carrageenan and at 4 h, 24 h, 48 h, 72 h after carrageenan injection. The local cutaneous BP was detected by Pericam Perfusion Speckle Imager (Pericam PSI) at the time after measuring of MWTs. The above two behaviors were compared and the relationship between them was analyzed. Results MWTs of the model group rats were decreased while BP significantly increased than that in the control group (P<0.01). The MWTs and BP in the model rats showed a negative correlation, especially the correlation index showed significant differences at 4 h and 72 h after carrageenan injection (P<0.01). Conclusions Carrageenan-induced acute inflammation in rats causes significant changes in mechanical pain threshold, which has a negative correlation with local cutaneous blood perfusion.

Abstract:Objective The aim of this study was to explore the establishment method of an animal model of irritable bowel syndrome (IBS) and the evaluation of this animal model. Methods 30 adult SD rats were randomly divided into two groups: acetic acid irritation and bondage stress group (n=10),bondage stress group (n=10),and normal control group (n=10). The rats of the intervention group received an intra-colonic infusion of 0.4% acetic acid irritation combined with bondage stress to establish an animal model of IBS. The colonic sensitivity of the intervention group rats was assessed by stool test and colorectal distension (CRD) test. Hydrochloric acid toluidine blue staining was used to observe the number degranulation phenomenon of mast cells in the ileocecum. Results On the 7th day, the number of soft feces was 8 and loose stool was 4 in the model group, significantly higher than that in the bondage stress group(0 and 0) (P<0.05),and normal control group (1 and 0) (P<0.05). On the 10th day, when the AWR=2, the average rectal distension volume was 1.2 mL, significantly lower than that in the bondage stress group(1.37mL) (P<0.05),also significantly lower than in the normal control group (1.49 mL) (P<0.05), and when the AWR=4, the average rectal distension volume was 1.49 mL, significantly lower than that in the bondage stress group(1.74mL) (P<0.05),and the normal control group (1.77 mL) (P<0.05). These results indicated that the visceral sensitivity of the model group was significantly higher than that in the bondage stress group and normal control group. Histological analysis showed that the rats of all groups had no obvious inflammatory changes. Conclusions Chronic bondage stress combined with intra-colonic infusion of 0.4% acetic acid irritation can be used to increase the visceral sensitivity and amount and degranulation of mast cells in the intestinal tissue in rats. This established rat model shows pathogenetic changes resembling the pathogenesis of human irritable bowel syndrome, and provides a useful animal model for further studies of the pathogenesis of this disease.

Abstract:Objective To analyze the survival curves of ASIC3^-/- and TRPV1^-/- mice, and provide a reference for further breeding of these strains of mice. Methods Forty-four ASIC3^-/-mice and sixty-one TRPV1^-/-mice were included in this study. The survival of the mice was observed in normal feeding for 500 days, survival curves were drawn, and their survival was analyzed. Results With the passing of time, the survival probability was decreased in ASIC3^-/-mice and TRPV1^-/- mice. The survival probability of TRPV1^-/-mice was significantly better than that of ASIC3^-/- mice (P =0.004, P<0.01). No significant difference was observed between the males and females of the same strain. Conclusions The survival probability of TRPV1^-/-mice is better than that of ASIC3^-/- mice. There is no significant gender difference in the two strains of mice.

Abstract:Objective The staffs of biosafety level 3 laboratories (BSL-3) face with the stress of handling highly pathogenic microbs and special laboratory environment. The job stress may result in accidents in the laboratory as negative factor for the risk control. The research may provide support for the control of risk in biosafety laboratories. Methods In order to assess the job stress in the staff in BSL-3 laboratory, we modified "the Chinese simple job stress questionnaire" based on the theory of the JDC mode and ERI mode, and an investigation was carried out. The present study included the staffs (87 employees) from six BSL-3 laboratories located in five provinces (Shanghai, Zhejiang, Jiangsu, Fujian and Wuhan). Results Analysis of the data indicates that variables of age, working years, job duties, manipulating of animals, type of microorganisms and transmission route have a significant influence on the level of job stress in BSL-3 laboratory. Conclusion The BSL-3 laboratory staff in higher stress level have the characteristicses: 20-39 years old, short work years, regular staff, operating on air-borne microbiology, manipulating of animals and operating on one more microbiology.