Oxidative stress injury and mitochondrial dysfunction are major obstacles to neurological functional recovery after ischemic stroke. The development of new approaches to simultaneously diminish oxidative stress and resist mitochondrial dysfunction is urgently needed. Inspired by the overproduced reactive oxygen species (ROS) at ischemic neuron mitochondria, multifunctional nanoparticles with ROS-responsiveness and mitochondrial-targeted (SPNPs) were engineered, achieving specific targeting delivery and controllable drug release at ischemic penumbra. Due to the nose-to-brain pathway, SPNPs which were encapsulated in a thermo-sensitive gel by intranasal administration were directly delivered to the ischemic penumbra bypassing the blood‒brain barrier (BBB) and enhancing delivery efficiency. The potential of SPNPs for ischemic stroke treatment was systematically evaluated in vitro and in rat models of middle cerebral artery occlusion (MCAO). Results demonstrated the mitochondrial-targeted and protective effects of SPNPs on H₂O₂-induced oxidative damage in SH-SY5Y cells. In vivo distribution analyzed by fluorescence imaging proved the rapid and enhanced active targeting of SPNPs to the ischemic area in MCAO rats. SPNPs by intranasal administration exhibited superior therapeutic efficacy by alleviating oxidative stress, diminishing inflammation, repairing mitochondrial function, and decreasing apoptosis. This strategy provided a multifunctional delivery system for the effective treatment of ischemic injury, which also implies a potential application prospect for other central nervous diseases.

Objective: To investigate the duration of Norovirus (NoV) shedding among infected school children during a NoV outbreak in a kindergarten,and to provide scientitic basis for epidemic prevention and control. Methods: Specimens and epidemiological data were collected from suspected cases, and specimens were detected using real-time RT-PCR to determine whether or not infecting with NoV. Specimens were collected every 3-7 days from NoV-infected children until specimens became negative for NoV. Results: A total of 14 suspected cases were reported, and 12 of them were infected with NoV. The average duration of NoV shedding was (26.58±17.94)d. The specimens among 9 from 12 Nov-infected cases were positive at 7 days, 8 NoV-intected cased remained positive at 14 days and 7 Non-infected cased at least 21 days. Conclusion Since NoV shedding duration among NoV-infected children tends to longer than their isolation time during outbreaks, reinforcement of hygiene practices among these school children is especially necessary to reduce the risk of virus secondary transmissions after their return to school.

Objective:To observe the structural and functional changes of each nucleus group in generalized anxiety disorder(GAD) rat models before and after the massage therapy, and to explore the central regulating mechanism of the massage therapy in GAD.Methods:60 Wistar male rats were randomly divided into blank group, model group and abdominal rubbing group, 20 rats for each group. GAD rat models were established by chronic emotional stress, and the models were evaluated by the elevated cross maze experiment. In the abdominal rubbing group, the GAD rats were treated with abdominal rubbing once a day for 10 min for 14 days. In the control group, the GAD rats were only bound to the experimental platform once a day for 10 min for 14 days. Horseradish peroxidase (HRP) retrograde tracking marker method was used to detect the changes of the structure of each nuclear cluster in the affective loop of the GAD rats in each group. The liquid-mass spectrometry quantitative analysis was used to determine the relative concentrations of N-acetyl aspartate (NAA), glutamic acid, choline and creatine in nuclear cluster of the GAD rats in each group.Results:Compared with the blank group, the HRP labeled cells in the rats of model group were less expressed and the activity of the emotional circuit in the brain was weak. The NAA/creatine ratio in the left hippocampal tissue of the rats in the model group was significantly increased than that of the blank group(0.94±0.08 vs 0.79±0.10, P<0.05), the glutamic acid/creatine ratio in the right hippocampal tissue was significantly decreased (0.95±0.10 vs 1.12±0.13, P<0.01), and the NAA/creatine andglutamic and acid/creatineratios in the left cortical tissue were all significantly decreased (1.04±0.05 vs 1.41±0.23, and 1.21±0.04 vs 1.57±0.11, all P<0.01). Compared with the model group, the hippocampal tissues of the GAD rats in the abdominal rubbing group had a large number of HRP aggregation and spread to the surrounding tissues, the NAA/creatine and glutamic acid/creatine ratios in the left hippocampal tissue of the abdominal rubbing group were significantly decreased (0.74±0.21 vs 0.94±0.09 and 0.92±0.20 vs 1.21±0.12, all P<0.01). The differences between the model group and the abdominal rubbing group in the ratio of glutamic acid/creatine in the right hippocampal tissue (1.01±0.23 vs 0.95±0.10), the ratio of NAA/creatine in the left cortical tissue (1.12±0.09 vs 1.04±0.05), and the ratio of glutamic acid/creatine in the left cortical tissue (1.22±0.12 vs 1.21±0.04) were not statistically significant ( P>0.05). Conclusions:Abdominal rubbing can effectively enhance the activity of affective loop and improve the relative concentration of neuron metabolites in hippocampal and cortical tissues in the affective loop, suggesting that the mechanism of GAD treatment by abdominal rubbing may be closely related to the structure and function of regulating affective loop.

Objective:To observe the effect of abdominal mechanical stimulation on rats with irritable bowel syndrome-Diarrehea (IBS-D), and to explore the possible mechanism of abdominal massage mechanical stimulation to improve IBS-D.Method:60 newborn Wistar rats were randomly divided into blank group, model group and abdominal massage group, 20 rats for each group. The IBS-D rat model was established by separating the mother rats and newborn rats. In the abdominal massage group, the IBS-D rats were treated with abdominal rubbing once a day for 14 days. In the model group, the IBS-D rats were only bound to the experimental platform once a day for 5 min for 14 days. The rats in blank group were not made model and with no intervention. The intestinal motility and visceral sensitivity of rats were measured by the time of glass bulb expulsion and the abdominal lift volume threshold. The pathological changes of rat colon tissue were observed by hematoxylin-eosin staining. The changes of mast cells in colon tissue were observed by toluidine blue staining. The ultramicrostructure of intestinal glial cells was observed by transmission electron microscope. The content of proinflammatory factors IL-6 and IL-1β in rat plasma was determined by ELISA.Results:Compared with the model group, mechanical stimulation of the abdominal massage can significantly prolong the discharge time of the glass beads [(2.5±0.2) min vs (1.6±0.2) min], increase the abdominal lift volume threshold of rats [(0.5±0.1) ml vs (0.4±0.1) ml], improve the pathological state of the colon tissue, and reduce the number of mast cells [(2.64±0.22) per field vs (5.61±0.12) per field], reduce the number of mitochondria in the intestinal glial cells and increase the density of heterochromatin, and can also reduce the secretion of proinflammatory factors IL-6 [(189.4±4.7) pg/ml vs (224.8±8.6) pg/ml] and IL-1β [(178.4±7.1) pg/ml vs (191.4±8.4) pg/ml], and the differences were statistically significant (all P<0.05). Conclusions:Mechanical stimulation of abdominal massage can increase the visceral sensitivity of IBS-D rats, regulate intestinal glial cells and reduce the secretion of proinflammatory factors. The mechanism may be related to the intestinal-brain axis.

Objective To investigate the effect and molecular mechanism of the combination of mechanical strain stimulation and icariin (ICA) on inhibiting the differentiation of osteoclasts induced by fatigue load stimulation. Methods The mouse mononuclear macrophage cell line RAW264.7 was cultured in vitro, and the blank control group was α-MEM complete medium. In the fatigue load group, RAW264.7 cells were treated with 5000 μεmechanical stretch strain, and then cultured in an osteoclast culture medium that was an α-MEM complete medium containing 40 ng/ml macrophage colony-stimulating factor and 40 ng/ml osteoclast differentiation factor. In the mechanical stimulation + ICA group, RAW264.7 cells were treated as the same procedure in the fatigue load group, and then cultured in an α-MEM complete medium containing 1 ×10 -5 mol/L ICA simultaneously with a 1000 μεtensile strain on the substrate. The activity of tartrate-resistant acid phosphatase (TRAP) was detected using a TRAP assay kit. The mRNA expression of the osteoclast marker genes, i.e. TRAP, cathepsin K(CTSK) and matrix metalloproteinase 9 (MMP-9) was detected by real-time RT-PCR. The nuclear translocation of nuclear factor kappa B (NF-κB) was analyzed by Western Blot. Results Compared with the fatigue load group, the combination of mechanical stimulation (1000 με substrate stretching) and ICA (1×10-5 mol/L) could significantly inhibit the activity of TRAP in osteoclasts (P<0.01) and reduce osteoclastosis. Moreover, that combination not only could down-regulate the mRNA expression of TRAP, CTSK and MMP-9 and the differences were statistically significant (all P<0.01), but also could inhibit the formation of osteoclasts by inhibiting the phosphorylation of P65, P50 and IκB-α in NF-κB signaling pathway. Conclusions The coupling of mechanical stimulation and ICA can effectively inhibit the osteoclast differentiation and the bone resorption induced by fatigue load, and the mechanism may involve regulating NF-κB signaling pathway.

Osteoporosis (OP) is one of the bone metabolic diseases which seriously harms the health and lives of people. The main cause of OP is that the balance between bone formation and bone absorption, i.e. the balance of the bone remodeling process,is no longer exist. When the bone absorption dominates the process, it will lead to osteopenia, destruction of bone microstructure and increased rate of fracture. Previous studies have shown that casein kinase 2-interacting protein-1 (CKIP-1) plays an important role in the process of bone tissue proliferation and differentiation. It mainly interacts with Smad ubiquitination regulatory factor 1 (Smurf 1) to affect bone metabolism. This review analyzes and summarizes the impact of CKIP-1 on bone tissue osteogenic differentiation direction and its mechanism, which may provide new idea and research orientation for future clinical treatment of osteoporosis.

Bone marrow mesenchymal stem cells (BMSCs) is a kind of multipotent adult stem cells,which is one of the most important seed sources of tissue engineering.Microgravity has inhibitory effects on osteogenic differentiation of BMSCs,which will cause bone mass reduction and changes of bone micro-structure that finally lead to osteoporosis.This process is regulated by multiple signaling pathways such as mitogen-activated protein kinase (MAPK) pathway,Notch pathway and Wnt/β-catenin pathway which co-regulated BMSCs osteogenic differentiation under microgravity.Studying the effects of microgravity on BMSCs into osteogenic differentiation can clarify the mechanism of bone loss,put forward new targets for the treatment of diseases and provide a useful reference for the development of China's space industry.

The effect of Smac gene on the TRAIL-induced apoptosis of the prostate cancer cell line PC-3 and the molecular mechanism were investigated. The Smac gene was transfected into PC-3 cells under the induction of liposome. The intrinsic Smac gene expression was detected by Western blotting. After treatment with TRAIL as an apoptosis inducer, in vitro cell growth activity was assayed by MTT colorimetry. The apoptosis rate of PC-3 cells was determined by annexin V-FITC and propidium iodide staining flow cytometry. The expression of cellular XIAP and caspase-3 genes was examined by Western blotting. Smac-transfected cells (PC-3/Smac group) had significantly increased Smac protein level as compared with PC-3 controls (P<0.01). After induction with 100-200 ng/mL TRAIL for 12-36 h, cellular proliferation rate in PC-3/Smac group was significantly lower than in PC-3 controls (P<0.05). After induction with 100 ng/mL TRAIL for 24 h, the apoptosis rate in PC-3/Smac group was significantly enhanced as compared with that of PC-3 controls (P<0.05). Accordingly, the XIAP expression level was down-regulated significantly (P<0.05) and caspase-3 subunit P20 was up-regulated significantly (P<0.05). It is suggested that the over-expression of cellular Smac can inhibit inhibitor of apoptosis proteins (IAPs), enhance caspases activity and the apoptosis rate of PC-3 cells induced by TRAIL, which may provide a useful experimental basis for prostate cancer therapy.

The effect of Smac gene on the TRAIL-induced apoptosis of the prostate cancer cell line PC-3 and the molecular mechanism were investigated.The Smac gene was transfected into PC-3 cells under the induction of liposome.The intrinsic Smac gene expression was detected by Western blotting.After treatment with TRAIL as an apoptosis inducer,in vitro cell growth activity was assayed by MTT colorimetry.The apoptosis rate of PC-3 cells was determined by annexin V -FITC and propidium iodide staining flow cytometry.The expression of cellular XIAP and caspase-3 genes was examined by Western blotting.Smac-transfected cells (PC-3/Smac group) had significantly increased Smac protein level as compared with PC-3 controls (P＜0.01).After induction with 100-200 ng/mL TRAIL for 12-36 h,cellular proliferation rate in PC-3/Smac group was significantly lower than in PC-3 controls (P＜0.05).After induction with 100 ng/mL TRAIL for 24 h,the apoptosis rate in PC-3/Smac group was significantly enhanced as compared with that of PC-3 controls (P＜0.05).Accordingly,the XIAP expression level was down-regulated significantly (P＜0.05) and caspase-3 subunit P20 was up-regulated significantly (P＜0.05).It is suggested that the over-expression of cellular Smac can inhibit inhibitor of apoptosis proteins (IAPs),enhance caspases activity and the apoptosis rate of PC-3 cells induced by TRAIL,which may provide a useful experimental basis for prostate cancer therapy.

In our previous study, we identified a novel testis-specific expressed gene 2 (TSEG-2) from mouse testis. To further investigate its functions, 35 male Balb/c mice (8 weeks old) were divided into cryptorchidism group (n=20), sham group (n=10), and control group (n=5). In cryptorchidism group, the right testes were anchored to the inner lateral abdominal wall. In situ hybridization (ISH) was applied to measure the localization of TSEG-2 in mouse testis. Real-time quantitative PCR was performed to detect the expression of TSEG-2 gene. Meanwhile, under the mediation of polyethylenimine (PEI), the recombinant vector pEGFP-TSEG-2 (n=5) or empty vector (mock, n=5) was transfected into the testis of male mice. The transfection efficiencies were measured under a fluorescence microscope. The apoptosis of spermatogenic cells was detected by terminal deoxynuleotidyl-mediated nick end labeling (TUNEL). The results showed that TSEG-2 was expressed in convoluted seminiferous tubules, more precisely, in spermatogonia and spermatocytes. As compared with sham and control groups, the TSEG-2 transcription was significantly enhanced (P<0.05) and was correlated with apoptosis of spermatogenic cells in cryptorchid testes (P<0.05). PEI was efficient in mediating transfection of TSEG-2 into seminiferous tubules of testis. One week post-transfection, intratesticular injection of TSEG-2 resulted in increased apoptosis of spermatogenic cells in vivo (P<0.05). These results indicate that TSEG-2 may participate in the apoptosis of spermatogenic cells and the pathogenesis of cryptorchidism.