用于白蚁防治的联苯菊酯微胶囊的制备及性能研究

针对白蚁防治药剂联苯菊酯传统加工剂型存在的安全性差、持效期短等缺点,采用溶剂蒸发法制备联苯菊酯微胶囊.通过粒径大小、外观形貌、包封率以及载药量筛选出最佳芯壁比、乳化剂用量和剪切时间,并对微胶囊理化特性及释放性能进行表征,同时考察微胶囊对白蚁的杀灭效果和持效性.研究结果表明,芯壁比为1:1.5,乳化剂用量为7％,剪切时间为6 min时制备的联苯菊酯微胶囊粒径适中(97.6μm),包封率高达70.5％,缓释性能良好,与市售乳油相比,对白蚁的杀灭效果相当,但持效性能优异.该研究获得的联苯菊酯微胶囊为安全、高效防治白蚁提供了技术手段.     

6种复配杀虫剂对七星瓢虫的毒力测定及风险评估

采用药膜法分别测定了10％甲维盐·茚虫威悬浮剂、12％甲维盐·虫螨腈悬浮剂、12％虫螨腈·虱螨脲悬浮剂、14％呋虫胺·螺虫乙酯悬浮剂、22％吡虫啉·螺虫乙酯悬浮剂和6％吡虫啉·高效氯氟氰菊酯悬浮剂6种复配杀虫剂对七星瓢虫Coccinella septempunctata Linnaeus幼虫急性毒性,并进行了初级风险评估.结果 显示,6种药剂对七星瓢虫48 h的LR5o(半致死用量,Median lethal rate)分别为0.812、2.255、4.082、22.735、6.755和0.00467 g a.i/hm2.在农田内暴露场景下,6种复配杀虫剂对七星瓢虫风险均不可接受;在农田外暴露场景下,仅有14％呋虫胺·螺虫乙酯悬浮剂和22％吡虫啉·螺虫乙酯悬浮剂对七星瓢虫风险可接受,其它均不可接受.结果 表明在田间最大推荐用量下,6种药剂对七星瓢虫的初级风险评价均存在高风险.     

The function and regulation of TET2 in innate immunity and inflammation

TET2,a member of ten-eleven translocation(TET)family as a-ketoglutarate-and Fe2+-dependent dioxygenase catalyzing the iterative oxidation of 5-methylcytosine(5mC),has been widely recognized to be an important regulator for normal hematopoiesis especially myelopoiesis.Mutation and dysregulation of TET2 contribute to the development of multiple hematological malignancies.Recent studies reveal that TET2 also plays an important role in innate immune homeostasis by promoting DNA demethylation or independent of its enzymatic activity.Here,we focus on the functions of TET2 in the initiation and resolution of inflammation through epigenetic regulation and signaling network.In addition,we highlight regulation of TET2 at various molecular levels as well as the correlated inflammatory diseases,which will provide the insight to intervene in the pathological process caused by TET2 dysregulation.     

Secondary Structural Transformation of Bovine Lactoferricin Affects Its Antibacterial Activity

Probiotics and Antimicrobial Proteins - Lactoferricin (Lfcin) is a potent antibacterial peptide derived from lactoferrin by pepsin hydrolysis. It was hypothesized that structural transformation of...     

Smoking increases oral mucosa susceptibility to Candida albicans infection via the Nrf2 pathway: In vitro and animal studies

Smoking and Candida albicans (C. albicans) infection are risk factors for many oral diseases. Several studies have reported a close relationship between smoking and the occurrence of C. albicans infection. However, the exact underlying mechanism of this relationship remains unclear. We established a rat infection model and a C. albicans-Leuk1 epithelial cell co-culture model with and without smoke exposure to investigate the mechanism by which smoking contributes to C. albicans infection. Oral mucosa samples from healthy individuals and patients with oral leucoplakia were also analysed according to their smoking status. Our results indicated that smoking induced oxidative stress and redox dysfunction in the oral mucosa. Smoking-induced Nrf2 negatively regulated the NLRP3 inflammasome, impaired the oral mucosal defence response and increased the oral mucosa susceptibility to C. albicans. The results suggest that the Nrf2 pathway could be involved in the pathogenesis of oral diseases by mediating an antioxidative response to cigarette smoke exposure and suppressing host immunity against C. albicans.     

Manipulation of host ecdysteroid hormone levels facilitates infection by the fungal insect pathogen,Metarhizium rileyi

Entomopathogenic fungi such as Metarhizium rileyi and Beauveria bassiana are widely used insect biological control agents. Little, however, is known concerning genetic or enzymatic factors that differentiate the mechanisms employed by these two fungal pathogens to infect target hosts. Infection by either of these organisms is known to increase levels of the growth and molting hormone, ecdysone, which also regulates the expression of a number of innate immune pathways. M. rileyi, but not B. bassiana, has apparently evolved an ecdysteroid-22-oxidase (MrE22O) that inactivate ecdysone. We show that deletion of MrE22O impaired virulence compared with the wild-type strain, with an increase in ecdysone titer seen in hosts that was coupled to an increase in the expression of antimicrobial genes. An M. rileyi strain engineered to overexpress MrE22O (MrE22O^OE), as well as trans-expression in B. bassiana (Bb::MrE220^OE) resulted, in strains displaying enhanced virulence and dampening of host immune responses compared with their respective wild-type parental strains. These results indicate that ecdysone plays an important role in mediating responses to fungal infection and that some insect pathogenic fungi have evolved mechanisms for targeting this hormone as a means for facilitating infection.     

高盐溶液预处理幽门螺杆菌对蒙古沙土鼠胃黏膜损伤作用

目的探讨高盐预处理的幽门螺杆菌(H.pylori)对胃黏膜的损伤作用。方法将30%高盐预处理前后的胃癌来源的H.pylori菌株(4854)灌胃蒙古沙土鼠(MGs),在灌胃后13、26和73周解剖动物,通过组织病理学检查、免疫组化染色和黏膜厚度测量,探讨高盐预处理的H.pylori对胃黏膜的损伤作用。结果与未加盐预处理的相应菌株相比,高盐预处理组小鼠的慢性炎症、黏膜变性/坏死、腺体萎缩伴肠上皮化生的发生率较低,黏膜糜烂/溃疡和黏膜上皮增生的发生率较高,差异均有统计学意义(t=8.325 6,P=0.040 8)。第73周,高盐预处理4854菌株组胃体和胃窦黏膜增生显著高于未加盐预处理组(t=12.802 4,P=0.035 1;t=16.536 0,P=0.043 8)。结论高盐预处理改变了H.pylori的体内致病性,有助于阐明H.pylori感染与高盐饮食在胃病中的相互作用模式。     

补充益生菌对功能性腹泻患者焦虑抑郁状态的影响

目的探讨益生菌对功能性腹泻患者临床症状和心理健康的影响。方法将2019年3月至2019年12月在广东省肇庆市高要区人民医院消化内科门诊收治的伴有焦虑抑郁状态的90例功能性腹泻住院病人随机分为试验组、对照组A、对照组B。三组受试者均口服匹维溴铵,试验组口服双歧杆菌四联活菌,对照组A服用氟西汀,对照组B未给其他药物治疗,疗程均为1个月。治疗前后,比较患者大便次数及性状、汉密尔顿焦虑量表(HAMA)和汉密尔顿抑郁量表(HAMD)评分。结果治疗前三组患者每周排便不同次数的人数比较,差异无统计学意义(P0.05)。治疗第3周和第4周后,与对照组A相比,对照组B和试验组的排便不同次数的人数差异具有统计学意义(P0.05)。治疗第4周后,试验组与对照组B的排便不同次数的人数比较,差异具有统计学意义(P0.05)。治疗前3组患者Bristol粪便性状评分比较差异无统计学意义(P0.05)。治疗第3和第4周后,与对照组A相比,对照组B和试验组的Bristol粪便性状评分比较,差异有统计学意义(P0.05)。治疗第4周后,试验组与对照组B的Bristol粪便性状评分比较,差异有统计学意义(P0.05)。治疗后与对照组A比较,对照组B和试验组HAMA评分和HAMD评分显著低于对照组A,且差异具有统计学意义(P0.05)。与对照组B比较,试验组HAMA评分和HAMD评分显著低于对照组B(P0.05)。结论通过补充益生菌可调节功能性腹泻患者腹泻次数,提高功能性腹泻患者生活质量,改善患者焦虑抑郁症状。     

体外诊断试剂防腐剂的选择策略

对体外诊断试剂中防腐剂的作用机理及选择原则进行了阐述,并对目前常用的防腐剂如叠氮钠、庆大霉素、硫柳汞、异噻唑啉酮类等的性能进行了比较,为体外诊断试剂的研究开发及生产中防腐剂的使用提供有益指导。