Abstract:Objective To determine the transcriptomic profile of AD mice and controls by RNA?Seq, in order to identify differentially expressed genes and reveal the molecular mechanism of AD. Methods Nine?month?old APP/ PS1 mice and age?matched wild?type C57BL/6 J mice were selected, with five female mice included in each group. Genome?wide analysis of mRNA expression in the prefrontal cortex of AD mice and controls was performed by RNA?Seq. qRT?PCR was used to verify the six key genes. Then, cluster analysis, Gene Ontology (GO) function enrichment analysis, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were used to analyze gene function. Results The result showed that a total of 224 genes were differentially expressed in the two groups ( P < 0. 05, |logFC| > 1. 0): 205 genes were upregulated and 19 genes were downregulated. When qRT?PCR was used to validate the six key genes, the result were consistent with the RNA?Seq. GO enrichment analysis result showed that the differentially expressed genes are involved in immune response, inflammatory response, chemokine activity, and IgG binding. KEGG pathway enrichment analysis revealed that these genes participate in phagosome, lysosome, toll?like receptor signaling pathway, cytokine?cytokine receptor interactions, and the NF?κB signaling pathway. Conclusions Differentially expressed genes related to AD were obtained, which provides an important experimental basis for the usage of a double?transgenic mouse model to study AD?related mechanisms and pharmacological intervention.

Abstract:Objective The cell cycle regulator MCM5 plays a critical role in the initiation of DNA replication and also functions in transcriptional regulation. However, its role in embryonic development is largely unknown. The aims of this study were to examine the expression pattern of mcm5 in early zebrafish embryos and investigate its function in somitogenesis. Methods First, the expression pattern of mcm5 was analyzed by whole?mount in situ hybridization in zebrafish during early embryonic development. Then, antisense morpholinos (MOs) were injected into embryos to disturb Mcm5 protein expression and the associated defects of somitogenesis were examined. Results MCM5 is a maternal factor that is ubiquitously expressed from the one?cell to early?somite stage. mcm5 transcripts are restricted to the tailbud, somite, and head at later stages. These result indicate the possibility that mcm5 is involved in somitogenesis. mcm5 morphants exhibit a shortened anterior?posterior axis and smaller eyes compared with control embryos. In situ experiments further revealed that some genes crucial for somitogenesis are downregulated during somitogenesis when mcm 5 is depleted. Conclusions mcm5 is involved in zebrafish somitogenesis.

Abstract:Objective Two models of rat kidney stone disease were constructed to provide support for exploration of the etiology of kidney stones. Methods Sixty rats were randomly divided into a nanobacteria group (NB group, tail vein injection of 1. 2 mL NB suspension, 30 rats) and an ethylene glycol group (EG group, 1. 25% ethylene glycol water +1% ammonium chloride 2 mL/ d gavage, gavage duration of 2 w, 30 rats). The experimental period was 10 w. In each group, 3 rats were sacrificed each week, with blood, urine, and kidney specimens being collected before sacrifice. Results There were no significant differences in the general conditions between the two groups, including no difference in renal body ratio ( P > 0. 05). There was also no significant difference in the number of pathological crystallizations. In addition, there were no significant differences of serum calcium, magnesium, phosphorus, creatinine, and uric acid between the two groups ( P > 0. 05), and also no difference of urea ( P > 0. 05). There were no significant differences of urine calcium, urine pH, urine specific gravity, and 24 h urine volume between the two groups ( P > 0. 05). Conclusions No statistically significant differences in terms of research indicators were identified between the two modeling method, indicating the feasibility of nanobacterial modeling. Compared with the conventional method of using ethylene glycol, NB has the advantage of being milder and being derived from kidney stones themselves. This model is more similar to the formation of human kidney stones and more conducive to study of the causes of kidney stones.

Abstract:Objective The immune function of older people decreases with increasing age, while immunosenescence confers increased susceptibility to influenza. After infection, the clinical symptoms of elderly patients are particularly serious, associated with a poor prognosis. Therefore, an aged mouse model that reflects clinically severe influenza virus infection should be established to evaluate the immune responses upon elderly host infection. Methods For this purpose, aged C57 mice (18 -24 months old) were infected with influenza viruses with different levels of virulence, H7N9 (high pathogenicity) and H9N2 (low pathogenicity). We analyzed the weight change and survival after infection. We also dynamically detected viral replication, expression of inflammatory factors, and pathological damage of lung. Results In contrast to adult mice (6 -8 weeks), aged mice lost 30% of their body weight 7 days after infection with H9N2 (adult controls lost only 10%), and the survival rate was reduced to 50% (that of the adult controls was 100%).H9N2 virus replication in the lung of aged mice was higher ( P < 0. 01) and peaked (RNA virus copy number in each gram of lung reached 3. 2 ×10 ⁴ ) on the second day after infection. Inflammatory cytokines (IL?6) and chemokines (MCP?1) were excessively expressed and associated with inflammation in the aged lung, at levels 100 to 1000 times those in the adult control. Lung injury of aged mice was more severe and the repair time after infection was longer. Conclusions We successfully established a model of aged mouse infection. This can reproduce the immune responses in clinical infection, such as infection survival, lung virus replication, and inflammation injury. This model could be important for understanding the mechanism of aging host infection or for evaluating anti?infective drugs.

Abstract:Objective To observe the change of heart rate variability (HRV) in rats with bundling or isoflurane anesthesia and determine the differences of weight, pain threshold, and hormone levels of the HPA axis between rats with bundling and isoflurane anesthesia for 9 days (30 min/ day). Methods Male SD rats were randomly divided into three groups: a control group, bundling group, and isoflurane anesthesia group. By recording an electrocardiogram (ECG) for 15min, heart rate and HRV were analyzed in the three groups in an acute experiment. Body weight, pain threshold, and levels of CRH and ACTH (in serum, hypothalamus, and adrenal glands) were investigated after the 9?day intervention (30min/ day). Results 1) Compared with the control group, the heart rates of the bundling and isoflurane anesthesia groups increased significantly (both P < 0. 01). The heart rate of the bundling group also increased compared with that of the isoflurane anesthesia group ( P < 0. 05). Moreover, compared with the control and bundling groups, SDRR and HF values of the isoflurane anesthesia group were significantly decreased ( P < 0. 01, P < 0. 05) and LF and LF/ HF values were significantly increased ( P < 0. 05, P < 0. 01). 2) After the 9?day intervention, compared with that in the control group, the weight gains of the bundling and isoflurane anesthesia groups were decreased ( P < 0. 05). The weight gain of the bundling group was also decreased compared with that of the isoflurane anesthesia group ( P < 0. 05). 3) Compared with those in the control and isoflurane anesthesia groups, the pain threshold in the bundling group was decreased ( P < 0. 05), while there was no significant difference between the control group and the isoflurane anesthesia group. 4) Compared with the levels in the control and isoflurane anesthesia groups, the levels of corticotropin releasing hormone (CRH) in the hypothalamus and corticosterone (CORT) in the adrenal gland were decreased ( P < 0. 05). There was no significant change in the levels of CRH and CORT in serum ( P > 0. 05). Conclusions The low concentration of isoflurane caused an increase of heart rate and a decrease of heart rate variability in rats. It result ed in change in the functional status of the autonomic nervous system, which mainly involved sympathetic excitement. Compared with the control group, the 9?day bundling intervention caused chronic stress in rats. Isoflurane anesthesia is a method of reducing stress in rats during long?term interventions.

Abstract:Objective To compare and analyze the blood physiological and biochemical indexes of normal Bama minipigs and the F5 generation of a minipig family with hyperglycemia. Methods The fasting blood glucose, postprandial 2 h blood glucose, insulin, glucagon, glycosylated hemoglobin, insulin resistance index, blood physiological index, and blood biochemical index were measured in normal Bama minipigs and the F5 generation of a hyperglycemic family; the intravenous glucose tolerance test was also performed. Results The fasting blood glucose, postprandial 2 h blood glucose, glycated hemoglobin, and insulin resistance index in the hyperglycemic group were significantly higher than those in the normal group ( P < 0. 05). The intravenous glucose tolerance test showed that the fasting blood glucose, 30 min blood glucose level, and 120 min blood glucose level in the hyperglycemic group were significantly higher than those in the normal group ( P < 0. 05). In the blood physiological and biochemical tests, the cholesterol and low?density lipoprotein cholesterol levels in the hyperglycemic group were significantly higher than those in the normal group ( P < 0. 05), but the differences of the other indexes were not pronounced. Conclusions The F5 generation of Bama minipigs showed hyperglycemia and abnormal lipid metabolism.

Abstract:Objective To investigate the influence of Qingre Huatan Jiedu prescription on lung tissues of rats with apoplexy?associated pneumonia, and its relationships with the Akt/ c?Jun amino terminal kinase 3 (JNK3) / caspase?3 and nuclear factor κB (NF?κB) signaling pathway. Methods SD rats were divided into a sham group, model group (cerebral ischemia reperfusion lung injury rats), Qingre Huatan Jiedu prescription low?dose group (7 mg/ kg), intermediate?dose group (14 mg/ kg), high?dose group (28 mg/ kg), and nimodipine group (200 mg/ kg), with 24 rats in each group. Pathological changes of lung tissues in rats were observed by the naked eye and hematoxylin?eosin staining (HE). The wet weight and dry weight of lung tissues and arterial oxygen partial pressure in rats were also measured, enzyme?linked immunosorbent assay was used to determine the oxidative index level in lung tissue, while western blot and immunohistochemistry were used to detect Akt, p?Akt, JNK3, p?JNK3, Caspase?3, p65, and p50 expression. Results Compared with those in the sham group, W/ D, PMN, MDA, TNF?α, IL?1β, lung tissue classification, lung tissue pathological score, the expression of p?JNK3, Caspase?3, p65, and P50 protein, and the positive expression rates of p?JNK3, p65, and P50 protein of lung tissue in the model group were all increased, while PaO2 , OI, SOD, the expression of p?Akt protein, and positive protein expression in lung tissue were all decreased. Compared with those in the model group, W/ D, PMN, MDA, TNF?α, IL?1β, lung tissue classification, lung tissue pathological score, the expression of p?JNK3, Caspase?3, p65, and P50 protein, and the positive expression rates of p?JNK3, p65, and P50 protein of lung tissue in the positive group and the Qingre Huatan Jiedu prescription group were all decreased, while PaO2 , OI, SOD, the expression of p?Akt protein, and positive protein expression in lung tissue were all decreased, in a dose?dependent manner ( P <0. 05). Conclusions Qingre Huatan Jiedu prescription has a certain protective effect against lung injury in rats with apoplexy?associated pneumonia. Its mechanism of action may be related to inhibition of the JNK3/ Caspase?3 and NF?κB signaling pathway and activation of Akt expression.

Abstract:Objective To investigate the effects of Icariin on the androgen receptor signaling pathway in orthotopic transplanted tumor of SCID mice with prostate cancer. Methods Sixty?four male SCID mice were randomly divided into a model group and experimental groups A, B, and C, and subjected to intraprostatic injection of a human prostate cancer cell line (LNCaP) suspension to establish a prostate cancer orthotopic transplantation tumor model. After modeling for 2 weeks, experimental groups A, B, and C were gavaged by doses of 10, 40, and 80 mg/ kg, respectively, for 5 weeks, while the model group was administered saline for comparison. RT?PCR was used to detect androgen receptor (androgen receptor, AR) and expression of tensin homolog deleted on the tenth chromosome (phosphatase and tensin homolog phosphatase gene deleted on chromosome ten, PTEN). Western blotting was used to detect the specificity of a prostate cancer antigen (prostate?specific antigen, PSA) and phosphorylated AR (p?AR). Flow cytometry was used to characterize the cell cycle of LNCaP prostate cancer cells. Results After treatment, the expression levels of AR, p?AR, and AR mRNA were higher in the model group, while the expression of PTEN mRNA was low. The tumor inhibition rate of the model group was lower, and there was no significant difference between the tumor mass and the tumor volume before and after treatment ( P > 0. 05). In groups B and C after treatment, the inhibition rates were(42. 53 ±5. 72)% and(44. 81 ±4. 76)%, AR, p?AR, and PSA mRNA had low expression, and PTEN mRNA had high expression. Moreover, the proportion of cells in G0 / G1 phase decreased, the proportion of cells in S phase increased, and the proliferation of tumor cells was arrested in S phase, when compared with those in the model group, before and after treatment ( P < 0. 05). Conclusions Icariin may inhibit the proliferation of prostate cancer LNCaP cells by inhibiting the phosphorylation of AR, enhancing the expression of PTEN, and blocking the proliferation of tumor cells in the S phase.

Abstract:Objective In this study, the molecular mechanism by which microRNA?494 inhibits osteoblast differentiation and matrix mineralization through the TLR?4 pathway was examined. Methods The mouse osteoblast strain MC3T3?E1 was selected as an in vitro model, which was transfected with miR?494 mimic. The expression of miR?494 before and after this transfection was determined by qRT?PCR. The proliferation of MC3T3?E1 before and after transfection was also detected by MTT assay, while the differentiation was studied by measuring ALP activity. In addition, matrix mineralization of this cell line was determined by quantitative detection of osteocalcin (OC) and Von Kossa calcification staining. Finally, the difference of TLR?4 protein expression before and after transfection was determined by Western blotting. Results Compared with that in the negative control group, the mRNA expression of miR?494 after transfection of the mouse osteoblast cell line MC3T3?E1 was significantly increased ( P < 0. 05). The result showed that miR?494 mimic was transfected into this cell line and successfully led to the overexpression of miR?494. Compared with the negative control group, after transfection with miR?494 mimic, the proliferative capacity of mouse MC3T3?E1 osteoblasts was inhibited ( P < 0. 05). ALP activity in MC3T3?E1 was also significantly decreased after transfection ( P < 0. 05), indicating that the differentiation ability of MC3T3?E1 cells was inhibited. At the same time, the activity of OC in MC3T3?E1 was significantly decreased after transfection ( P < 0. 05) and the number of mineralized nodules was also significantly decreased ( P <0. 05), which indicated that the overexpression of miR?494 inhibited the mineralization of matrix in these cells. Western blot result showed that TLR?4 protein expression was significantly increased in cells transfected with miR?494 mimic, compared with that in the negative control group ( P < 0. 05). Conclusions miR?494 could inhibit the proliferative activity of the mouse osteoblast line MC3T3?E1 through the TLR?4 pathway, reduce the activity of ALP and OC in cells, decrease the number of mineralized nodules in osteoblasts, and inhibit osteoblast differentiation and matrix mineralization.

Abstract:Objective To analyze and compare the skin corrosion of Wistar and SD rats by using the transcutaneous electrical resistance (TER) test method . Methods In accordance with the OECD TG 430 procedure and Chinese Safety and Technical Standards for Cosmetics, Wistar rats and SD rats were used to test the skin corrosivity of 12reference chemicals, with the result being compared between the two strains. Results After testing by TER, the result for the two strains of rats, using the OECD guidelines, showed the same conclusion for the corrosivity of the 12 chemicals; the sensitivity was 50% and the specificity was 100%. When using the Chinese Safety and Technical Standards for Cosmetics, the findings for the two strains of rats were not consistent with the judgment on the corrosion associated with 4?(methylthio)? benzaldehyde, while the same conclusion of corrosivity were made for the other 11 reference chemicals. The sensitivity for the Wistar rats was 100% and the specificity was 83. 3%, while the sensitivity and specificity for the SD rats were all 100%. Conclusions The two strains of rats showed result largely in accordance with the skin corrosion result upon the testing of 12 reference chemicals by TER. SD rats could thus be used instead of Wistar rats in the TER test.

Abstract:Objective To investigate the effect and molecular mechanism of Dendrobium candidum polysaccharides on chronic atrophic gastritis (CAG) induced by N?methyl?N′?nitro?N?nitrosoguanidine (MNNG) in rats. Methods To establish the CAG model, Wistar rats were first provided free access to MNNG drinking solution containing 167 g/ mL distilled water for 8 weeks. Then, the high?dose Dendrobium candidum polysaccharide group was given 1. 34 g/kg of raw drug per day by gavage, the medium?dose group was given 0. 67 g/ kg, and the low?dose group was given 0. 335g/ kg. Weiyangshu granules at 4. 0 g/ kg were administered to the groups every day. Normal saline was administered to a model group, in which no intervention was performed. Twelve weeks after the treatment, the stomach tissue was removed, and subjected to analyses of the histology and levels of stomach gastrin release, interleukin?6, PCNA, tumor necrosis factor alpha, Janus kinase 2, and activating factor?3/ tyrosine phosphorylation?3. Results 1) After 12 weeks of treatment, the body weight of the model group was significantly lower than that of the normal group ( P < 0. 01).. The weights of the three groups with different dosages of Dendrobium polysaccharide and the Yangweishu group were significantly higher than that of the model group ( P < 0. 05). The body weight of the high?dose Dendrobium candidum polysaccharide group was significantly higher than that of the Yangweishu group ( P < 0. 05). (2) The grade of inflammation in the model group was significantly higher than that in the normal group ( P < 0. 01). The numbers and thicknesses of chief cells and parietal cells in the model group were significantly lower than those in the normal group ( P < 0. 05), while the number of glands in the normal group and the thickness of the rats were thick and thick chief cells and parietal cells were significantly higher than those in the model group ( P < 0. 05). In the three dose groups of Dendrobium candidum polysaccharide, the grade of inflammation of gastric tissue, number of glands, gland thickness, chief cell, and parietal cells in the Yangweishu group recovered significantly ( P < 0. 05). (3) The level of GAS in the model group was significantly lower than that in the normal group. The amount of IL?6 in the model group was significantly higher than that in the model group ( P < 0. 05). The level of IL?6 in the normal group was significantly lower than that in the model group ( P < 0. 05). The levels of GAS in the three dosage groups of Dendrobium candidum polysaccharide and the Yangweishu group were significantly higher than that in the model group ( P < 0. 05). The IL?6 content in the high?dose group of Dendrobium candidum polysaccharide was significantly lower than that in the model group ( P < 0. 05). (4) The PCNA mRNA and TNF?α mRNA levels in normal model rats were significantly lower than those in the normal model group ( P < 0. 05). PCNA mRNA and TNF?α mRNA levels in the high?dose group of Dendrobium candidum polysaccharide were significantly lower than those in the model group ( P < 0. 05). (5) The expression of JAK2/ β?actin and p?STAT3/ STAT3 in the high?dose group of Dendrobium candidum polysaccharide was significantly lower than that in the model group ( P < 0. 05). Conclusions Dendrobium officinale polysaccharide has good protective and reversal effects on CAG rats, effectively restoring weight and alleviating gastric mucosal atrophy. One of its mechanisms may be to improve gastric mucosal pathology by inhibiting the activation of the JAK2/ P?STAT3 signaling pathway.

Abstract:Objective To determine the expression of the Dlx 2 gene in skull tissue of the small?tailed Han sheep skull defect model, and to investigate its significance in this skull defect. Methods Ten small?tailed Han sheep aged one month old were selected to establish the skull defect model. Newborn skull tissue in the defect area and native skull tissue adjacent to the defect area were collected. Dlx 2 expression at the mRNA and protein levels was determined by real?time PCR and western blotting. Results Compared with the levels in native skull tissue adjacent to the defect area, the Dlx 2 mRNA and protein expression of newborn skull tissue in the defect area was significantly increased ( P < 0. 05). Conclusions Increased Dlx 2 gene expression may play an important role in the repair of skull defects.

Abstract:Objective To explore the mechanisms of epidermal homeostasis during aging. Methods Bioinformatic analysis software was used for GO analysis and KEGG signal pathway analysis based on microarray data [genes and microRNAs (miRNAs)]. Cytoscape (v. 3. 5. 1) was used to predict the miRNA?gene interaction network and key genes. Results The result of this study revealed the differential expression of miRNAs related to the human epidermis and that their target genes are involved in associated signaling pathways. Conclusions The identified epidermal signaling pathways provide a theoretical basis for improving the treatment of age?related skin diseases.

Abstract:Objective The possibility of using non addictive analgesics in a pharmacological teaching experiment was explored in order to continue the traditional analgesic experiment. Methods One hundred ICR mice were randomly divided into five groups: saline control group, meloxicam (5 mg/ kg) group, aspirin (0. 6 g/ kg) group, antodine (1. 2mL/ kg) group, and pethidine (5 mg/ kg) group. Mouse pain models were established using hot plate and acetic acid torsional method . Each group was administered their respective substances by intraperitoneal injection. The analgesic effects were observed for the non addictive analgesics compared with those in the control group and the addictive analgesic group. Results The result showed that the analgesic effects of meloxicam, aspirin, antodine, and pethidine were significantly higher than in the control group, when tested with the acetic acid torsional method ( P < 0. 001); those in the aspirin, antodine, and pethidine groups were superior to that in the meloxicam group ( P < 0. 01); and that in the antodine group was superior to those in the aspirin and pethidine groups ( P < 0. 05). Moreover, when tested with the hot plate method , the analgesic effects of aspirin, antodine, and pethidine were significant compared with that in the control group ( P < 0. 05, P < 0. 01), while those in the antodine and pethidine groups were better than for aspirin ( P <0. 01). Conclusions As nonaddictive analgesics, meloxicam, aspirin, and antodine can take the place of addictive analgesics in teaching experiments.

Abstract:Objective To investigate bacterial infection in laboratory rats and mice from production facilities in Shanghai. Methods Programs for monitoring bacteria in laboratory animals were compared between China and elsewhere. A total of 848 samples were collected from the laboratory animal production facilities of Shanghai from 2014 to 2016. Helicobacter spp. , C. rodentium, C. bovis, S. aureus, P. aeruginosa, and K. pneumoniae were tested by PCR for the monitoring project. Results S. aureus contamination was not identified in SPF facilities in 2014 and 2016. K. pneumoniae contamination was not identified in clean level facilities in 2014. There were different degrees of contamination by other pathogens in facilities of different levels. Helicobacter spp. and C. bovis could be detected in all clean level facilities. Helicobacter spp. , C. rodentium, and C. bovis were detected in animals at all levels. The rates of positivity for Helicobacter spp. and P. aeruginosa declined over time, but those of C. rodentium, C. bovis, and K. pneumoniae rose. Conclusions This study investigated the prevalence of bacteria in rats and mice in Shanghai from 2014 to 2016. This work should promote the quality of laboratory animals and the levels of feeding and management, and also provide an important reference for the optimization of standards for laboratory animals.

Abstract:Experimental animals have made tremendous contributions to medical research. However, the absence of education on the welfare of experimental animals has resulted in poor ethical awareness and a lack of scientific understanding on this issue among medical graduate students. As a result , they may fail to treat experimental animals appropriately and can not scientifically, rationally, and humanely use these animals to carry out scientific research. To enhance the ethics of medical graduate students, medical colleges and universities should standardize the curriculum and strengthen the knowledge and education of experimental animal welfare; explore qualification certificates for employment and normalize the system of research permits; follow the 3Rs’ principle and ensure experimental animal welfare during medical research; strengthen practice supervision; and make ethical reviews a priority. This should improve the behavior regarding the use of experimental animals among medical graduate students.

Abstract:Experimental animals are important for life science research and development, and for medical development and human health. Experimental rabbits were reared and bred by rabbits with clear genetic backgrounds and clear sources, and they were trained to control the microorganisms and parasites they carrying. Experimental rabbits are widely used in scientific research, teaching, production, identification, and other scientific experiments. Cages provide living space for experimental rabbits. This article mainly analyzes the characteristics of a new type of dry raising rabbit cage with regard to the feeding and management of experimental rabbits, welfare ethics, and the technical design of cages.

Abstract:FK506 binding protein 1B (FKBP1B), a member of the FKBP family, is mainly expressed in myocardium, brain tissue, and smooth muscle. Its roles in the heart and nervous system have received increasing attention in recent years, and a number of experiments have confirmed FKBP1B’s involvement in important physiological activities in heart development, disease, brain aging, and nerve dysfunction. Thus, the regulatory mechanisms and mechanisms of action of FKBP1B in the heart and brain have become matters of increasing importance. Through continuous exploration, FKBP1B has been found to be able to control Ca ^{2 +} release by binding to RyR2 receptors in both myocardium and brain tissue. This article reviews FKBP1B’s functions and regulatory mechanisms in heart and brain tissue in order to provide a theoretical basis for understanding the physiological and pathological mechanisms of the cardiovascular and cerebrovascular systems in the fight against human diseases.

Abstract:Multiplex PCR is a new molecular biology detection technology, which is highly efficient, rapid, convenient, specific, and sensitive. It overcomes the shortcomings during amplification in conventional PCR and enables the synchronous detection of multiple pathogens in a single reacting system. It can thus provide new clues for research on differential diagnoses and the genotyping of resistance genes in a clinical context. This paper summarizes the research background and principles of multiplex PCR, and its use for the detection of viruses, bacteria, and parasites as well as microbial resistance in experimental animals. This paper provides a reference for the use of multiple PCR technology for detecting pathogens causing experimental animal epidemics and the establishment of method to combat them.

Abstract:Tryptophan?2,3?dioxygenase (TDO) is a heme?containing tetrameric protein that exhibits specific catalytic activity for L?tryptophan. TDO assists oxygen into the indole gene of tryptophan and then catalyzes it into kynurenine (KYN). Nervous tissues play an important role in the human body, but cannot regenerate. Tryptophan metabolism is closely related to the physiological function of nerves. Activation of TDO leads to the depletion of tryptophan and the accumulation of KYN and its metabolites, which can affect the function of neurons and cause related immune disorders. Mounting evidence obtained in recent studies indicates that TDO play an important role in the pathophysiology of several brain diseases. This paper summarizes the biological functions of TDO in the neurological diseases schizophrenia, Alzheimer’s disease, and glioma, with the aim of emphasizing TDO’s effect in tryptophan metabolic pathways and related neurological diseases. This should guide the development and application of TDO?specific inhibitors, which could provide new treatments for certain neurological diseases.

Abstract:Animal experiments have often been conducted in sports science research. Laboratory animal welfare should always be guaranteed in animal experiments. This paper discusses the status of the 3Rs’ principle and proposes requirements and analyzes the progress of implementation of the 3Rs’ principle in sports science research.

Abstract:Euthanasia is a key welfare issue and focus of ethical reviews in laboratory animal experiments. With increased awareness of the importance of animal protection and the promulgation and implementation of national standards of welfare ethics for laboratory animals, the issue of euthanasia has attracted increasing attention. Based on the current situation of the international application of euthanasia, this paper expounds the main problems associated with the implementation of euthanasia on laboratory animals, compares the advantages and disadvantages of several euthanasia method commonly used globally, presents an ethical analysis, and proposes some suggestions.

Abstract:Laboratory animals play an increasingly important basic supporting role in research, development, and experiments in many industries and fields, such as life science and medicine. Their great contribution is often made via physical and mental suffering. It is thus extremely important to guarantee the welfare of laboratory animals based on the premise of ensuring reliable, scientific result of animal experiments. Considering the status of laboratory animal welfare in China, this paper points out the differences in this issue between China and developed countries, analyzes the reasons for the lag of laboratory animal welfare in China, proposes countermeasures and suggestions to overcome this, and clarifies the principles, features, main clauses, and key points of ethical review of China’s new national standards. This paper proposes that only by comprehensively and deeply understanding and standardizing the implementation of China’ s new technical standards for laboratory animal welfare and establishing a strict, scientific review and supervision system for laboratory animal welfare ethics can we promote the appropriate and rapid development of welfare of China’s laboratory animals.