Abstract:Objective Using zebrafish to analyze the effect of water temperature on the recovery of spinal cord injury. To detect the cell proliferation and changes of gene expression at the injury site during the process of recovery. Methods Surgical operation was performed to induce spinal cord injury (SCI) on adult fish. Water at a series of temperature was applied to culture the fish. Swimming ability was adopted to observe the recovery of spinal cord injury following surgery. Vibration sections and immunohistochemistry were performed to observe the cell number post SCI at different stages. The changes of gdnf and nos gene expression were determined by real-time PCR. Results The water temperature changes from 28℃ to 32℃ did not affect the swimming ability of non-injured and sham-injured fish (P>0.05). The swimming ability recovered mostly in 8 weeks post spinal cord injury. At 32℃, the swimming ability recovered faster than at 28℃ or at 30℃ (P<0.05). The cell proliferation increased obviously following spinal cord injury (P<0.05). The proliferation of cells surrounding the spinal cord in jury was more extensive in SCI fishes incubated in 32℃ water than in 28℃ or 30℃ water (P<0.05). Real-time PCR assay showed that gdnf was up-regulated in all groups post SCI at 24 h, and 7 and 14 days (P<0.05). The nos expression was up-regulated in all groups following SCI in 24 h (P<0.05) and 7 days. There was no significant difference between the SCI group and sham-injury group (P<0.05), while after 14 days, the expression of nos was reduced in the SCI group compared with the sham-injury group (P<0.05). Conclusions A slight increase of incubating water temperature can accelerate the recovery of spinal cord injury in zebrafish.

Abstract:Objective Based on the data detected using gene expression microarray, to select multiple reference genes and use them to quantify transcriptome genes of different abundance in the mouse liver tissue. Methods To detect global transcriptome genes in the mouse liver tissues using gene expression microarray. All the genes were sorted into different groups according to their expression level, followed by coefficient of variation (CV) analysis. Real-time quantitative polymerase chain reaction (qPCR) and geNorm software were used to further identify the reference genes. Results The expression levels of over 60,000 genes were obtained from microarray screening, and divided them into low, moderate and high expression groups. Finally six reference genes were screened, i.e. Casp2 and Lrrc14 as low abundance, Nrd1 and Trpc4ap as moderate abundance, and Atp5a1 and Clu as high abundance genes. Conclusions The six reference genes derived from microarray data can be used to accurately quantify the global transcriptome genes with various expression levels.

Abstract:Objective To investigate the effects of P-selectin gene knockout on the biological characteristics of mice. Methods P-selectin knockout (PKO) mice and C57BL/6 mice were housed in SPF environment. To make sure that the mice were pure PKO mice by gene identification. To determine the general condition, the activity status, reproduction of P-selectin knockout mice were observed and tested. HE staining was used to observed the histological morphology and structures of 6-week-old and 18-week-old P-selectin knockoutout mice. Results PKO mice and C57 mice have similar multiplication, there was no significant difference in reproduction and blood routine test. The stuctures of liver, spleen, lung and kidney were normal. Conclusions P-selectin knockout has no significant effects on reproduction, blood routine test and major organs.This research provides animal model theoretical basis for further study on the effects of P-selection in diseases.

Abstract:Objective Deletion detection and annotation of 18 lines from the population of specific chromosome 1 substitution strains (PCSSs)derived from Chinese wild mice based on whole genome re-sequencing data. Methods Whole genome re-sequencing of the 18 lines were performed on the Illumina Hiseq platform. SpeedSeq software was used to detect the deletion after read alignment. Further annotation was obtained using SnpEff software. Results 13 803 deletions were identified among the 18 lines, the length of deletion was ranged from 51bp to 70 kb, among them nearly 50% were less than 500 bp. Through functional annotation,we found most of the variants were located in intronic (50.361%) and intergenic (28.745%) regions. However, we also identified 31 protein coding genes harboring loss-of-function deletions. Among them, 3 genes were associated with human diseases, 7 genes were participated in 11 KEGG pathways. Conclusion The chromosome 1 of PCSSs harbors abundant deletion mutations which can be used as genetic markers in genetic studies.

Abstract:Objective To establish a rabbit model of steroid-induced femoral head and explore the effect of Taohong Siwu Decoction (THSWD), a traditional Chinese medicine prescription, on the repair of bone microstructure assessed by high-resolution MRI combinaed with Micro-CT. Methods 25 healthy 24-week old New Zealand rabbits (male:female=1:1) were divided into three groups:5 in the control group, 10 in the model group and 10 in theTHSWD treatment group. We establish the rabbit model with intramuscular injection of endotoxin (LPS) and methylprednisolone (MPS). The treatment group was given 0.3g/kg of THSWD for 8 weeks. The control group and model group were administred with equal volume water for 8 weeks. Then all the femoral heads of rabbits were taken and examined with high-resolution MRI, histopathology and Micro-CT. Results 1) The MRI of the femoral heads of model group revealed a wide range of lower density areas in high resolution MRI,that of the treatment group showed a relatively normal shape of the femoral head with small low density areas. Comparing the treatment group with model group, the values of ROE and ROE/NR were significantly decreased in the THSWD treatment group (P<0.05). 2) The pathological examination showed fracture of bone trabeculae, karyopyknosis, empty lacunae, necrosis of bone marrow cells in the model group (P<0.05). Empty lacunae rate in the model group was much higher in the model group than the normal one (P<0.05). In the THSWD treatment group, bone formation was active and a better trabecular morphology was observed. 3) The micro-CT imaging showed that compared the model group with control group, the values of BV/TV, Conn.D., SMI, Tb.N and Tb.Th in the model group were decreased, while BS/BV and Tb.Sp were increased. The values of BS/BV and Tb.Sp values in the treatment group were significantly lower, while Conn.D., SMI, and Tb.N were increased than that of the model group (P<0.05 for all). Conclusions The results of this study show that Taohong Siwu Decoction can promote the healing of steroid-osteonecrosis of femoral head, the repair of bone microstructure, and improve the biomechanics in the femoral head.

Abstract:Objective To induce skin cancer in BALB/c mice using DMBA as initiator and TPA as tumor promoter. Through optimizing the doses and frequencies of DMBA administration to establish a stable skin cancer model with less time and causing less skin damage. Methods Shaving the back of mice to expose a piece of skin around 2 cm×2 cm. The mice were divided into a blank control group and four treatment groups randomly. These four groups were given 1, 2, 4, 7 times 100 μg/100 μL DMBA/acetone, respectively, in the first week, and twice 4 μg/100 μL TPA/acetone per week in the next 11 weeks. The body weight changes, time of tumor formation and number of tumors formed were recorded during the experiment. The mice were sacrificed at 12th week and samples of tumor tissue and adjacent normal skin tissue were taken for pathological examination using HE staining. Results Tumors were observed at the 7th week in the group with once DMBA administration in the first week and at the 4th week in the group with twice DMBA administration in the first week. Skin cancers were formed also in the group with 4-time DMBA administration in the first week, however, with significantly more severe skin damages. The mice receiving DMBA everyday in the first week died at the 3th week. Conclusions The best induction protocol for skin cancer in BALB/c mice should be twice DMBA in the first week followed by twice TPA in the next few weeks. This protocol has the advantages of easy operation, short modeling time, high cancer formation rate, and presents a similar process of human skin carcinogenesis, thus, it can be used as a useful animal model for skin cancer research.

Abstract:Objective To establish a mouse model of lung adenocarcinoma brain metastasis with human luc⁺-PC-9 cells stably expressing luciferase and to compare the evaluation values of bioluminescence imaging and¹⁸F-FDG (¹⁸F-fluorodeoxyglucose) SPECT/CT in these models. Methods Suspension of luc⁺-PC-9 cells was injected into the left ventricle of BALB/c nude mice to establish a mouse model of brain metastasis from lung cancer. Bioluminescence imaging and¹⁸F-FDG SPECT/CT were used to evaluate the metastasis of tumors as compared with HE-staining pathology as a golden standard. Results The success rate of brain metastases was 85% through injecting luc⁺-PC-9 cells into the left ventricle. The number of tumor cells was positively related to the intensity of light, with a linear correlation (R²=0.96). Fluorescence was observed in the brain, spine and femur by bioluminescence imaging, and the metastases were confirmed by H & E pathological examination.¹⁸F-FDG SPECT/CT observed abnormal density collective foci in the spine or femur but not in the brain. Conclusions Injection of tumor cell suspension into the mouse left ventricle is a good method to establish a brain metastasis of lung cancer. Bioluminescence has a higher sensitivity and specificity in detecting brain metastasis and bone metastasis, with advantages of real-time, dynamical and non-invasive detection of tumor metastasis growth.¹⁸F-FDG SPECT/CT does not have superiority in detection of brain metastases but is suitable for detecting bone metastasis.

Abstract:Objective The purpose of this study was to compare the adenomyosis models in nude mice generated by four different methods,and to find out an optimal modeling method, and to provide an ideal animal model for exploring pathogenesis and experimental treatment of uterine adenomyosis.Methods 1. 80 female healthy nude mouse were divided randomly into 4 groups:Intraperitoneal implantation group,subcutaneous implantation group, intraperitoneal injection group, and subcutaneous injection group. The transplants were taken for pathological examination at 4 weeks after surgery.Results The success rate of intraperitoneal implantation group was 95%,and that of the subcutaneous implantation group was 45%,while the success rate of intraperitoneal injection group and subcutaneous injection group was 0%.Conclusions Establishment of a nude mouse model of uterine adenomyosis by intraperitoneal implantation method has a high success rate and with good stability, and is an ideal mouse model of human-derived uterine adenomyosis.

Abstract:Objective To analyze the changes in motor function during rat aging and explore whether treadmill training improves the age-related decrease of rat motor function.Methods 2-month-old, 8-month-old and 26-month-old SD rats were used in this study. The motor function parameters, including forelimb grip strength, endurance, rearing count and scurry speed were assessed before and after treadmill training for two weeks. Results 1)The forelimb grip strength, endurance, rearing count and scurry speed of the 26-month-old rats were significantly lower than those of the 2-month-old and 8-month-old rats.Moreover, the last three parameters were decreased with aging. 2) Treadmill training not only considerably improved the forelimb grip strength of 26-month-old and 8-month-old rats, but also increased the rearing count of 8-month-old and 2-month-old rats. 3) Treadmill training significantly increased the total scores of the motor function of 26-month-old rats.Conclusions The motor function parameters (forelimb grip strength, endurance, rearing count and scurry speed) of rats show an age-related decline. Importantly, treadmill training can improve the age-related decrease of total scores of the motor function. These four parameters can be used as aging parameters for motor function in rat models.

Abstract:Objective To investigate the effects of low frequency electroacupuncture on the P2X3 receptor expression in dorsal root ganglion (DRG) of rats with type II diabetic neuropathic pain. Methods Part 1:Fifty normal SD rats were randomly divided into normal group (8 rats) and model group (42 rats). The rat model of type II diabetic neuropathic pain was generated by high fat and high sugar diet with a single intraperitoneal injection of streptozotocin (STZ, 35 mg/kg). 2 Hz electroacupuncture was administered at ipsilateral acupoints Zusanli and Kunlun for consecutive 7 days. Insulin sensitivity index (ISI) was measured at 0 w and 5 w, and fasting plasma glucose (FPG) was measured at 0 w, 5 w, and 7 w. Paw withdrawal threshold (PWT) was measured by mechanical pain threshold, and P2X3 receptor was determined by immunofluorescence. Part 2:Twelve rats with diabetic neuropathic pain (DNP) were divided into EA+vehicle group (6 rats) and EA+αβ-meATP group (6 rats). Rats in the two groups received the same EA treatment as Part 1. Rats in the EA+αβ-meATP group were injected with P2X3 receptor agonist αβ-meATP (0.6 μmol/L, 100 μL) into the ventral surface of each hind paw every time before EA treatment. Rats in the EA+vehicle group received the same dose of vehicle (PBS buffer) as a control. Pain threshold of the rats were measured. Results ① Compared with the normal group, the ISI levels of the rats in DNP group was significantly decreased after 5 weeks of the high-fat high-sugar diet (P<0.01). Two weeks after STZ injection, the fasting plasma glucose levels in the rats receiving STZ were significantly elevated (P<0.01). The type 2 diabetes model was established with a successful rate of 69.04%. ② PWTs:The PWTs of rats in DNP group were reduced compared with rats in the normal group (P<0.01), indicating that the type 2 DNP model was successfully established. Compared with the PWTs of DNP-controlled rats, the 2 Hz electroacupuncture significantly increased bilateral PWT of rats subjected to DNP from day 3 after treatment (P<0.01). P2X3 receptor agonist αβ-meATP greatly reduced bilateral PWT of EA-treated DNP rats compared with that of the EA+vehicle group (P<0.01). ③The immunofluorescence essay showed that P2X3 receptor expression in bilateral L5 DRGs in the DNP group was significantly increased as compared with that in the normal group (P<0.01). The increases were inhibited by 2 Hz EA in L5 DRGs compared with the DNP group (P<0.01). Conclusions 2Hz electroacupuncture can effectively treat the type II diabetic neuropathic pain by decreasing the expression of L5 DRG P2X3 receptors in rats.

Abstract:Objective To study the effect of heart rate and behavior changes in Labrador retrievers determined by distance test (DT), and to provide effective behavior methodological and physiological basis for early screening of guide-dogs. Methods Sixty Labrador retrievers (8-15 months old; 22 females and 38 males) were provided by Chinese guide dog training centre of Dalian. 30 of the 60 dogs were guide dogs and the other 30 were eliminated dogs which were evaluated by examination in the training center. The "interest", "exploration" and "play invitation" behavioral categories in the distance test (DT) of the dogs were tested and the heart rates were simultaneously recorded. Results The mean heart rate of the guide dogs were significantly lower than those of the eliminated dogs during the DT (P<0.05). The scores of "interest", "exploration" and "play invitation" showed no significant difference between the guide dogs and eliminated dogs (P>0.05). Conclusions In the distance test, the changes of heart rates in guide dogs are significantly lower than eliminated dogs. The results of this study indicate that guide dogs have a more stable psychological quality and better control of emotions compared with eliminated dogs in the DT. Our study may provide a theoretical basis for the combination of DT and heart rate to predict the success rate of the guide dog training.

Abstract:Objective To analyze the tissue distribution, viral excretion and serological antibody in BALB/c mice artificially infected with minute virus of mice (MVM), and the natural infection status in mice. Methods Thirty-three SPF male 3-week old BALB/c mice were intraperitoneally injected with 0.2 mL of MVM in 1.2×10⁷ copies/μL concentration. The general status of the animals was observed daily post inoculation. The animals' tissue,faeces and serum samples were taken at 12 time points before and after inoculation (2-3 animals at each time point). QPCR method was used to detect the viral nucleic acid in tissues and feces, and the serological antibody against MVM was tested by ELISA. Meanwhile,other clinical samples of 1563 SPF mice and 158 mice in open housing were collected for testing the viral nucleic acid and antibody. Result There were no clinical symptoms and pathological changes among all infected mice. The viral loads of each tissue reached the peak at 4 d or 7 d post inoculation, and then were generally on a declining curve, but were still found at 60 d. Comparing the viral load in tissues showed that the highest tissue was liver, followed by kidney, spleen, stomach, heart, lung, cecum and brain. The viral loads in feces reached the peak at 11 d, and then dropped rapidly, but could be still detected at 60 d. The antibody could be detected at 7 d, and then gradually raised. The antibody dilution degrees reached 32 at 21 d, and maintained high levels with 16 to 128 during 32 d to 60 d. In the clinical samples, the nucleic acid tests were negative in SPF mice, however, a positive rate of 14.5% was found in mice in open housing. Meanwhile, the antibodies of MVM showed a low positive rate in SPF mice, and the positive rate was 68.3% in the mice in open housing. Conclusions The mice generally present occult infection after inoculation of MVM. However, the infected mice can shed virus in a long period, and viral loads of tissues and serological antibody can be maintained for a long time. Thus, MVM can be detected by testing viral nucleic acid and serological antibody.

Abstract:Objective To establish a mouse model of kidney-yin and kidney-yang deficiency after oral administration of hydrocortisone, and to explore the related evaluation factors.Methods The model was established by oral administration of hydrocortisone to induce kidney-yin and kidney-yang deficiency in mice. The survival and body weight of the mice were observed. The serum content of adrenal cortical hormone (ACTH), cortisol (Cor.) in the hypothalamic-pituitary-adrenal (HPA) axis, and thyroid stimulating hormone (TSH), triiodothyronine (T3), thyrox (T4) in the hypothalamic-pituitary-thyroid (HPT) axis, follicle-stimulating hormone (FSH), estradiol (E2), testosterone (T) in the hypothalamic-pituitary-gonadal (HPG) axis were determined by radioimmunoassay.Results The body weight of kidney-yin and kidney-yang mice were decreased, the serum ACTH, Cor, TSH, T3, T4 contents were decreased, the serum FSH, E2, T contents were increased in the kidney-yang deficiency model mce (P<0.01), and those parameters in the kidney-yin deficiency model mice were changed in opposite direction. Conclusions It is found that the hormone levels of ACTH, Cor, TSH, T3, T4, FSH, E2 and T in kidney deficiency mice are changed, and cortisol can be used as an important index to evaluate the model of kidney deficiency induced by glucocorticoid.

Abstract:Objective The aim of this study was to explore the effect of androgen deficiency on serum hormone levels, visceral fat accumulation and inflammatory gene expression in miniature pigs fed a high-fat diet (HFD). Methods Sexually mature male Chinese Wuzhishan miniature pigs were divided into three groups (animals/group) as follows:intact male pigs (SHAM), castrated male pigs (CAS) and castrated male pigs plus testosterone treatment (CAS+T). The pigs were fed a HFD diet for 12 weeks. Serum levels of testosterone and leptin were measured and visceral fat were dissected and weighted. qRT-PCR was performed to determine the mRNA expression levels of lipogenic, lipolysis and inflammation related genes. Results (1) Serum testosterone levels were significantly decreased but serum leptin levels were significantly increased in the castrated pigs. These effects were recovered after testosterone treatment. (2) Visceral fat percentage was significantly increased in the castrated pigs, and testosterone treatment reduced the increased visceral fat in the castrated pigs. (3) Castration and testosterone treatment had no significant effects on the expression levels of lipogenic genes (FAS and ACC) and lipolysis genes (HSL and ATGL) in pigs fed a HFD. (5) Castration significantly induced the expressions of inflammatory genes including Leptin, CD68, CCL16, CCL23 and SAA, and testosterone treatment recovered the expressions of the above genes in the castrated pigs. Conclusions Castration-induced testosterone deficiency promotes visceral fat accumulation and upregulates the expression levels of inflammatory genes in miniature pigs fed a HFD. Moreover, testosterone treatment ameliorates castration-induced visceral fat accumulation and inflammatory response in HFD-fed pigs.

Abstract:Objective To study the function of LSD1 in the development of neurons and the influence of LSD1 on mood and memory-related behavior in mice. Methods The LSD1^(flox/flox) transgenic mice were crossed with Nestin-cre^(Tg) transgenic mice, using Cre-LoxP recombination system, to generate LSD1 conditional knockout of neural stem cell (LSD1-CKO) mice, LSD1^(flox/flox) Nestin-cre^(Tg) mice, and LSD1^(flox/flox) mice as control. The neuron proliferation in LSD1-CKO mice was further detected by immunofluorescence staining. At the same time, the mood and memory-related behavior of LSD1-CKO mice were examined using several methods:sucrose preference test (SPT), forced swimming test (FST) and novel-object recognition (NOR) assay. Results In the LSD1 brain-specific CKO mice, the neuron proliferation rate in the hippocampus was significantly reduced (P=0.023), the preference for sucrose was reduced (P=0.0075), immobility duration during the forced swimming test was increased (P<0.05), and LSD1-CKO mice also exhibits memory-decline (P=0.0019) during the novel-object recognition test. Conclusions Depletion of LSD1 in mouse brain neural stem cells leads to significant reduction of the neuron proliferation in the hippocampus. LSD1-CKO mice show more negative emotions and memory impairment.

Abstract:Objective To investigate the antidepressant effect of DS-1226, a hydrolysate of ginsenosides, on a mouse model of depression induced by chronic sleep interruption, and provide scientific evidence for the research and development of antidepressant drugs. Methods 72 male ICR mice were divided into control group, model group, positive control group (paroxetine hydrochloride, 10 mg/kg) and 3 treatment groups (20 mg/kg, 40 mg/kg, 80 mg/kg of DS-1226). Except the control group, the other mice were put into a rotary roller (parameter settings:1 min/rev;rest 2 min after 1 rev) for 3 days of drum adaptation, 3 h/d. Then making model for 14 days in the roller(parameter settings:1 min/rev;rest 2 min after 1 rev). The antidepressant effects of DS-1226 were evaluated by weight monitoring, open-field test, tail suspension test, and forced swimming test. Results After 14 d sleep disturbance, compared with the control group, the body weight, immobility time in tail suspension test and forced swimming test were significantly decreased in the model group. Compared with the model group, DS-1226(40 mg/kg)significantly reversed the weight loss caused by sleep disturbance. Paroxetine significantly reduced the immobility time of tail suspension test. DS-1226 (40 mg/kg, 80 mg/kg)significantly decreased the immobility time of tail suspension test, and DS-1226 (80 mg/kg) significantly decreased the immobility time of forced swimming test. Conclusion The hydrolysate of ginsenosides DS-1226 shows antidepressant effect on mouse model of depression induced by chronic sleep interruption.

Abstract:Objective To breed a guinea pig inbred strain and set up a method for detection of the microsatellite markers of genetic structure in guinea pigs. Method Using inbreeding methods we try to breed the Zmu-1:DHP inbred strain. With 15 pairs of polymorphism microsatellite primers, the genetic homozygosity of Zmu-1:DHP inbred strain,Zmu-1:DHP outbred strain and Zmu-2:DHP inbred strain (as control) were examined by PCR. Results After breeding for 13 years, 8 sublines of Zmu-1:DHP inbred strain (>20 generations) were bred. After identification, the gene frequency of the second subline of Zmu-1:DHP inbred strain was 86.7%,higher than Zmu-1:DHP outbred strain (6.7%) and Zmu-2:DHP inbred strain (66.7%). The average number of loci of Zmu-1:DHP inbred strain was 1.13,lower than that of Zmu-1:DHP outbred strain (2.47%) and Zmu-2:DHP inbred strain (1.33%). The genotypic frequency of Zmu-1:DHP inbred strain was also higher than that of the other strains. The gene types of Zmu-1:DHP inbred strain were included in the genes of Zmu-1:DHP outbred strain, but Zmu-1:DHP inbred strain was short of 2 characteristic genes. The gene homozygous rates of 8 sublines of Zmu-1:DHP inbred strain were different with each other,among them, those of the 2nd and 8th sublines were higher than others. Conclusions There are both homozygosity and specificity in the Zum-1:DHP inbred strain and Zum-1:DHP outbred strain. The second Zum-1:DHP subline becomes a new inbred strain guinea pig. It is essential that the subline with the characteristic property is screened from these sublines. The guinea pigs of black Zmu-2:DHP inbred strain carrying microsatellite markers not present in the white strains, may carry optimal genes related with hair color properties.

Abstract:Objective To study the distribution of intestinal autofluorescent microorganisms in the rat intestine at different developmental stages.Methods The distribution of intestinal autofluorescent microorganisms in rat intestine at various developmental stages was tested and evaluated using a small animals living imaging system. First, standard E. coli strain was tested by fluorescence detection in vitro. Then, the distribution of E. coli under the same test conditions was tested.The intestinal autofluorescent bacteria distribution was detected in the SD rats at 3 days,14 days and 60 days of age.After expanding the range of excitation wavelength fluorescence detection,removing the background of fluorescence feed and feces and other foreign autofluorescent substances. Results E. coli can be excited in the range of 485-535 nm wavelength and to emit fluorescence. E. coli mainly existed in the stomach and only a few E. coli were found in the ileum of 3-days old SD rat.. In the 14-days old rats, E. coli mainly existed in the stomach and cecum, and only a few E. coli were found in the ileum. In the 60-days old SD rats, E. coli mainly existed in the ileum, and only a few E. coli were found in the colon, cecum and jejunum. After the expansion of the excitation light wavelength range of fluorescence detection, E. coli were observed mainly in the ileum, and only a few E. coli were found in the stomach in 3-days old SD rat.E. coli mainly existed in the stomach, then the cecum and only a few E. coli were found in the ileum and jejunum in 14-days old SD rats.E. coli could be found in the whole intestinal system but mainly in the ileum and cecumin of the 60-days old rats. Conclusions Examining the intestinal autofluorescent microbes with the small animal in vivo imaging system can be helpful and make guidance to study the distribution of intestinal microbes in the host at different developmental stages, and to provide a basis for studying the relationship of intestinal microbes with its host and the gastrointestinal drug administration.

Abstract:Chronic liver diseases can further develop to liver fibrosis and cirrhosis. Currently, there is no effective treatment except liver orthotopic transplantation at this point. The extreme shortage of liver organ source forced people to find alternative treatment strategies. Mesenchymal stem cells (MSCs) have the abilities of immunomodulatory, hepatocyte differentiation, promotion of liver cells regeneration in situ and inhibiting the activation of hepatic stellate cells. Therefore, MSCs transplantation provides a very broad prospect for cell therapy. It is important to provide preclinical evaluation of the efficacy and safety before the application of cell therapy in clinical trials. The progress of various animal models of human liver diseasees and significance of using MSCs to treat liver diseases in preclincal studies based on these animal models were reviewed in this paper.

Abstract:Sufficient embryos are needed for the preservation of Beagle dogs germplasm resources and the preparation of gene-modified human disease animal models.Up to now, the induced ovulation technique has no effect on dogs,it is hard to obtain mature oocytes in vivo, although the scientists try a lot in many aspects, but still could not make a breakthrough. The in vitro maturation rate is too low to support the preservation of germplasm resources, application in gene-modified disease models and biomedical research. Aiming to provide useful information on breakthrough in dog oocytes maturation, this review will summarize the effect of different age and reproductive stage,different morphology and size of the oocytes and lipid droplet on the in vitro maturation of dog oocytes.