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981.
Superoxide is the single-electron reduction product of molecular oxygen generated by mitochondria and the innate immune enzyme complex, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (Nox), and its isoforms. Initially identified as critical to the host defense against infection, superoxide has recently emerged as an important signaling molecule and as a proposed mediator of central nervous system injury in stroke, neurodegenerative conditions, and aging itself. Complete understanding of superoxide in central nervous system disease has been hampered by lack of noninvasive imaging techniques to evaluate this highly reactive, short-lived molecule in vivo. Here we describe a novel optical imaging technique to monitor superoxide real time in intact animals using a fluorescent probe compound and fluorescence lifetime contrast-based unmixing. Specificity for superoxide was confirmed using validated mouse models with enhanced or attenuated brain superoxide production. Application of fluorescence lifetime unmixing removed autofluorescence, further enhanced sensitivity and specificity of the technique, permitted visualization of physiologically relevant levels of superoxide, and allowed superoxide in specific brain regions (e.g., hippocampus) to be mapped. Lifetime contrast-based unmixing permitted disease model-specific and brain region-specific differences in superoxide levels to be observed, suggesting this approach may provide valuable information on the role of mitochondrial and Nox-derived superoxide in both normal function and pathologic conditions in the central nervous system.  相似文献   
982.
The objective of this paper was to extract and purify lily polysaccharide and to study its anti-H22 hepatoma effect in mice. Orthogonal experimental method was used to analyze the factors influencing the extraction and purification of lily polysaccharide, and the anti-tumor effect of lily polysaccharide was studied by acting it on H22-bearing mice. The results showed that the size of influence of various factors on the extraction results of lily polysaccharide were extraction time, extraction times and extraction temperature in decreasing order. Lily polysaccharide can enhance the immune function of H22 tumor-bearing mice, and inhibit the growth of H22 tumor. The study concluded that the optimal conditions for the extraction and purification of lily polysaccharide should be extraction times of 3 times, an extraction time of 4 h each, and an extraction temperature of 60°C; lily polysaccharide has an anti-tumor effect.  相似文献   
983.
984.
Under Korean field conditions, coinfection with porcine circovirus type 2 (PCV2) and porcine reproductive and respiratory syndrome virus (PRRSV) is most commonly observed in porcine respiratory disease complex (PRDC). Despite the wide use of PCV2 vaccination, PRDC remains a serious respiratory problem. Thus, the objective of this study was to determine and compare the efficacy of 4 one-dose PCV2 vaccines on 3-week-old pigs with an experimental PCV2-PRRSV challenge at 17 weeks postvaccination. Regardless of which commercial PCV2 vaccine was used, the vaccination of piglets at 3 weeks of age was efficacious against cochallenge of PCV2 and PRRSV, on the basis of growth performance and PCV2-associated lesions. However, the inactivated chimeric PCV1-2 and the PCV2 vaccines induced higher PCV2-specific neutralizing antibody (NA) titers and PCV2-specific gamma interferon-secreting cells and lower PCV2 viremia levels than the two PCV2 subunit vaccines. The vaccination of piglets against PCV2 at 3 weeks of age was effective in reducing PCV2 viremia and PCV2-associated lesions during the finishing period, which is an age at which pigs are frequently affected by PRDC caused by coinfection with PCV2 and PRRSV under Korean field conditions.  相似文献   
985.
Recovery time and quality after general anaesthesia is important for patient safety. This study aimed to determine whether intravenous lipid emulsion could improve recovery profiles from isoflurane anaesthesia in adult patients undergoing laparoscopic cholecystectomy. Sixty‐six patients were enrolled. After anaesthesia induction, inspired isoflurane concentration was adjusted to maintain stable vital signs and the suitable conditions for operation. At the end of the operation, the isoflurane was discontinued, and either 2 ml/kg 30% lipid emulsions or 0.9% saline solution was administered intravenously. The time to eye opening, extubation and exit from the operation room was recorded, and the quality of recovery from anaesthesia was assessed. Sixty patients completed the study. The median time to eye opening and exit from the operation room was significantly shorter in the lipid emulsion group than in the saline group [15.5 (interquartile range 9.0) versus 20.0 (10.0) min., = 0.01; 19.5 (8.3) versus 23.6 (6.3) min., = 0.04, respectively], whereas the median time to extubation did not show any noticeable difference. The quality of recovery was better in the lipid emulsion group than that of the saline solution group with respect to drowsiness visual analogue scale score (< 0.01), Observer's Assessment of Alertness/Sedation score (< 0.01), Mini‐Mental State Examination score (= 0.04) and Modified Aldrete Post Anaesthesia Recovery score (= 0.03). No serious adverse events were observed during the study period. In conclusion, intravenous lipid emulsion may effectively improve the recovery time and quality from isoflurane anaesthesia for laparoscopic cholecystectomy.  相似文献   
986.
Protein arginylation by arginyl–transfer RNA protein transferase (ATE1) is emerging as a regulator protein function that is reminiscent of phosphorylation. For example, arginylation of β-actin has been found to regulate lamellipodial formation at the leading edge in fibroblasts. This finding suggests that similar functions of β-actin in other cell types may also require arginylation. Here, we have tested the hypothesis that ATE1 regulates the cytoskeletal dynamics essential for in vivo platelet adhesion and thrombus formation. To test this hypothesis, we generated conditional knockout mice specifically lacking ATE1 in their platelets and in their megakaryocytes and analyzed the role of arginylation during platelet activation. Surprisingly, rather than finding an impairment of the actin cytoskeleton structure and its rearrangement during platelet activation, we observed that the platelet-specific ATE1 knockout led to enhanced clot retraction and in vivo thrombus formation. This effect might be regulated by myosin II contractility since it was accompanied by enhanced phosphorylation of the myosin regulatory light chain on Ser19, which is an event that activates myosin in vivo. Furthermore, ATE1 and myosin co-immunoprecipitate from platelet lysates. This finding suggests that these proteins directly interact within platelets. These results provide the first evidence that arginylation is involved in phosphorylation-dependent protein regulation, and that arginylation affects myosin function in platelets during clot retraction.  相似文献   
987.
988.
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990.
OBJECTIVE: To systematically investigate the safety of Xingxue Shuxuening injection(SXN) in preand post-marketing, and to ensure clinical drug safety.METHODS: Strict quality control in raw herb selection and production processes was adopted and pharmacology research on SXN was performed by the drug manufacturing company, Heilongjiang ZBD Pharmaceutical Co., Ltd. We systematically reviewed the safety literature of Xingxue SXN. Adverse drug reaction(ADR) data of the drug, extracted from Spontaneous Reporting System(SRS), and clinical characters based on 20 hospital information systems(HIS) in China, were analyzed. Large-scale prospective safety monitoring and Risk Minimization Action Plans(Risk MAPs) of XingxueSXN were carried out.RESULTS: The quality of SXN was stable and controllable when it was produced. Drug toxicology studies found no effect on rabbits with hemolytic or condensed, local stimulation and muscle stimulation, and no allergic reactions in guinea pigs. The ADRs of Xingxue SXN were dizziness, phlebitis,and vomiting based on SRS data. The injection did not conform to instructions in clinical practice when we analyzed HIS database, and patient's abnormal blood urea nitrogen levels may be related to the drug, when analyzed using the propensity score method. A nested case-control study was designed and performed to analyze the influencing factors of suspected allergic reactions to SXN. The study showed that patients with an allergy history were more prone to allergic reactions(P〈0.001),and some medicine combinations could cause allergic reactions.CONCLUSION: These studies have established a body of evidence on Xingxue SXN safety, and provide a good model for Chinese medicine injection for clinical safety. The Xingxue SXN production process and toxicology research indicate the safety of the injection. However, the use of the injection is not consistent with instructed clinical practice.Xingxue SXN causes ADRs perhaps from inappropriate usage or its  相似文献   
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