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991.
Lactoferrin (LF) can downregulate allergic airway inflammation in asthma. However, the in vivo effect of exogenous LF on allergic rhinitis (AR), a disease attributed to airway inflammation, has yet to be determined. We investigated the effect of intranasal administration recombinant human (rh) LF and its underlying mechanisms on AR in BALB/c mice. Multiple parameters of allergic responses were evaluated to determine the effect of rhLF. We found that the number of eosinophils and goblet cells, as well as mRNA and protein expression of type 2 helper T (Th2), Th17 and regulatory T (Treg) cells in the nasal cavity, was significantly upregulated in AR mice compared with the controls, Conversely, administration of rhLF prior to or after intranasal ovalbumin challenge markedly downregulated these same parameters. Th1‐specific mRNA and protein expression in the nasal cavity of the controls was not different from that in AR mice, but expression significantly increased with rhLF treatment. The mRNA and protein expression of endogenous LF in the nasal cavity was significantly downregulated in AR mice compared with the controls. However, after rhLF treatment, endogenous LF mRNA and protein expression was significantly upregulated. Exogenous rhLF inhibited allergic inflammation in AR mice, most likely by promoting the endogenous LF expression and skewing T cells to a Th1, but not a Th2 and Th17 phenotype in the nasal mucosa. Our findings suggest that rhLF treatment may be a novel therapeutic approach for prevention and treatment AR.  相似文献   
992.
993.
Chemokines, by virtue of their ability to recruit immune cells into allografts, play critical roles in acute transplantation rejection. CCR9 and its ligand, CCL25, is one of the key regulators of thymocyte migration and maturation in normal and inflammatory conditions. Moreover, several studies have revealed that high expression of CCR9 and CCL25 participated in many kinds of diseases. However, the role of CCR9 in allograft rejection is still unclear. In this study, we established a murine skin transplantation model of acute rejection. Our findings showed that the proportion of CCR9-expressing T cells was significantly increased in the spleen of allotransplanted mice compared with syngeneic transplantation. Furthermore, expression of CCL25 in allograft was similarly increased. Neutralization of CCL25 by intravenous injection of anti-CCL25 monoclonal antibody significantly prolonged skin allograft survival, decreased the number of infiltrating cells, and simultaneously suppressed the chemotactic ability and the proliferation of the splenic T cells in response to allogeneic antigens. Finally, blockade of CCL25 also diminished the secretion of IFN-γ by splenic T cells. These studies indicated that CCR9/CCL25 was involved in acute transplantation rejection and anti-CCL25 strategies might be useful in preventing acute rejection.  相似文献   
994.
995.
We investigated whether the expressions of CCL5 and CCR5 participate in dysfunctional changes in human umbilical vein endothelial cells (HUVECs) induced by chronic high glucose treatment and examined whether neferine exerts its therapeutic effects by blocking the development of dysfunctional vascular endothelium. HUVECs were cultured with control or high concentrations of glucose in the absence or presence of neferine for 5 days. Nitric acid reductase method was used to detect the concentration of nitric oxide (NO) released into culture media. The level of intracellular reactive oxygen species (ROS) was measured by fluorescent DCFH-DA probe. The expressions of 84 genes related to endothelial cell biology were assessed by Human Endothelial Cell Biology RT2 Profiler PCR Array. The expressions of the chemokine CCL5 and its receptor CCR5 were further determined by real-time RT-PCR and western blotting. PCR array indicated that CCL5 was the most significantly upregulated when HUVECs were exposed to chronic high glucose; the intracellular ROS level and the expressions of CCL5 and CCR5 at both mRNA and protein levels were significantly increased, whereas NO production was decreased simultaneously. The increased level of ROS and elevated expressions of CCL5 and CCR5 at high glucose were significantly inhibited by neferine; meanwhile the decreased NO production upon chronic high glucose treatment was relieved. An antioxidant (vitamin E) exerted similar beneficial effects. These data indicate that neferine can reduce the upregulation of CCL5 and CCR5 of vascular endothelium exposure to chronic high glucose and prevent or inhibit subsequent occurrence of inflammation in blood vessels possibly through antioxidation.  相似文献   
996.
Ghrelin has a protective effect on diabetic encephalopathy. To expound the protective mechanism, we investigated the effects of ghrelin on high glucose-induced cell apoptosis and intracellular signaling in cultured PC12, which is a suitable model for studying neuronal cell death. High glucose-induced PC12 apoptosis was significantly inhibited by co-treatment of ghrelin. Sustaining inflammatory response is one of the molecular mechanisms of diabetic encephalopathy and TLR4 signaling has close relationship with inflammatory response. But there is no report about the biologic role of toll-like receptor 4/nuclear factor-κB (TLR4/NF-κB) signaling in controlling high glucose-induced PC12 apoptosis by ghrelin. In this study, we found that TLR4/NF-κB pathway was activated by high glucose stimulation in PC12 and significantly alleviated by the co-treatment of ghrelin. From these findings, we made the conclusion that ghrelin could attenuate the symptoms of diabetic encephalopathy, which alleviates inflammatory reaction of diabetic encephalopathy by regulating TLR4/NF-κB pathway.  相似文献   
997.
Wang  Jing  Xiao  Ling  Wang  Junling  Ding  Zijin  Ni  Jie  Long  Xiaoyan 《Neurological sciences》2021,42(12):5231-5239
Background

Ring chromosome 18 (r[18]) is a rare syndrome in which one or both ends of chromosome 18 are lost and the remaining chromosome rejoins to form ring-shaped figures. It is characterized by developmental delay/cognitive disability, facial dysmorphisms, and immunological problems. The phenotype associated with epilepsy is rare and has not yet been reported in China.

Methods

We report herein the case of a 12-year-old Chinese girl who presented with typical facial dysmorphisms, developmental delay, cognitive disability, hyperactivity, and epilepsy and discuss the clinical features of r(18) syndromes through comparison with previously described cases worldwide.

Results

We describe the characteristics of all seizures that have been reported in these cases and propose that the appearance of epilepsy in r(18) patients may be associated with the abnormality of chromosome karyotypes. Further studies are warranted to confirm this.

  相似文献   
998.
Yang  Sai  Wu  Liwen  Liao  Hongmei  Lu  Xiulan  Zhang  Xiao  Kuang  Xiaojun  Yang  Liming 《Neurogenetics》2021,22(4):323-332
neurogenetics - Mutations in CSNK2B lead to Poirier-Bienvenu neurodevelopmental syndrome (POBINDS), a rare neurodevelopmental disorder. Only 14 cases of POBINDS have been reported worldwide. The...  相似文献   
999.
Toxoplasma gondii infects all warm-blooded animals including humans, causing serious public health problems and great economic loss in the food industry. Commonly used serological tests involve preparation of whole Toxoplasma lysate antigens from tachyzoites which are costly and hazardous. An alternative method for better antigen production involving the prokaryotic expression system was therefore used in this study. Recombinant dense granular protein, GRA2, was successfully cloned, expressed, and purified in Escherichia coli, BL21 (DE3) pLysS. The potential of this purified antigen for diagnosis of human infections was evaluated through western blot analysis against 100 human serum samples. Results showed that the rGRA2 protein has 100 and 61.5 % sensitivity towards acute and chronic infection, respectively, in T. gondii-infected humans, indicating that this protein is useful in differentiating present and past infections. Therefore, it is suitable to be used as a sensitive and specific molecular marker for the serodiagnosis of Toxoplasma infection in both humans and animals.  相似文献   
1000.
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