波纹龙虱捕食蚊幼功能反应研究

作者于1991年7～9月,对波纹龙虱捕食淡色库蚊幼虫功能反应进行了研究。结果表明。在实验室条件下,波纹龙虱的捕食量随着蚊幼密度的增加而增大,其曲线符合Holling Ⅱ型功能反应,即其捕食量与猎物密度呈负加速曲线型。并根据Holling圆盘方程,建立了波纹龙虱捕食功能反应数学模型。波纹龙虱的寻找效应随着猜物密度的增加而降低。     

In Vivo Observation of Cutaneous Larva Migrans by Fluorescence-Advanced Videodermatoscopy

Fluorescence-advanced videodermatoscopy is not a widespread diagnostic technique. Its application in dermatology can facilitate the diagnosis of diseases such as cutaneous larva migrans by enabling us to recognize the precise position of larva in vivo on the skin. Using this noninvasive technique, we detected a case of cutaneous larva migrans in a patient.     

渤海鱼类和头足类异尖科线虫幼虫感染情况调查

[目的 ]调查渤海鱼类和头足类异尖科线虫幼虫感染情况 .[方法 ]对渤海 2 5种鱼 2 90尾和 3种头足类 10 8尾进行剖检 .[结果 ]发现 19种鱼 15 6尾和 1种头足类 8尾感染异尖科线虫幼虫 6种 ,计73 2 7条 .从 15种鱼 (N =191)中的 12 1尾 ( 63 4 % )和一种头足类 (N =5 4 )中的 8尾 ( 14 8% )体内检出简单异尖线虫幼虫 5 992条 ,占总数的 81 8% ,4种鱼是本幼虫的新发现宿主 .其余 13 3 5条幼虫中 ,15 4( 2 1% )条为鲔蛔线虫B型幼虫 ,采自 4种鱼 2 3尾 ;10 13 ( 13 8% )条为鲔蛔线虫C型幼虫 ,采自 13种鱼79尾 ;164( 2 2 % )条为宫脂线虫中国V型幼虫 ,采自 4种 2 0尾鱼 ;2种鱼感染针蛔虫幼虫 3条 ;仅发现 1条伪新地蛔虫幼虫 .     

猪粪饲养家蝇幼虫的营养成分研究

目的 :分析猪粪饲养家蝇 (Muscadomestica)幼虫的营养成分。方法 :引种野生家蝇 ,用猪粪饲养幼虫 ,收获 3期老熟幼虫 ,测定粗蛋白、粗脂肪、氨基酸和脂肪酸构成及微量元素含量 ,用粮食与农业组织 世界卫生组织 (FAO WHO)提出的参考蛋白模式评价 ,并与麦麸饲养的幼虫及鱼粉比较。结果 :每公斤猪粪平均可产(0 13± 0 0 4)～ (0 2 0± 0 12 )kg鲜蛆 ,鲜蛆烘干比为 1∶0 31± 0 12 ,粗蛋白 42 36 %～ 5 2 33 % ,必须氨基酸含量占总氨基酸的 45 10 % (E % ) ,必须氨基酸与非必需氨基酸总量的比值 (E/N)为 0 82 ,E % /T为 3 0 1,脂肪酸含量为 13 73 %～ 16 83 % ,油酸、亚油酸及亚麻酸等必需脂肪酸分别为 36 99% ,7 6 1%和 0 35 % ,Fe 2 91 5mg/kg ,Cu 87 5 5mg/kg ,Zn 2 46 8mg/kg ,Mn 2 49 45mg/kg ,比麦麸饲养幼虫更接近参考蛋白模式 ,营养价值优于鱼粉。结论 :猪粪饲养的家蝇幼虫比麦麸饲养的幼虫更接近参考蛋白模式 ,营养价值优于鱼粉     

家蝇幼虫抗菌蛋白的抗菌特性及其组成

目的观察不同诱导源诱导家蝇幼虫产生抗菌蛋白的抗菌特性及其蛋白组分.方法取5种诱导源诱导后提取抗菌蛋白,用不同细菌进行抑菌实验,观察5种诱导源诱导组抗菌蛋白的抗菌特性;5种诱导源诱导组抗菌蛋白经SDS-聚丙烯酰胺凝胶电泳,观察抗菌蛋白的组分变化.结果各诱导组产生的抗菌蛋白均能抗多种G＋菌、G-菌和耐药菌株,但对不同细菌的抗菌活性有所差别.各诱导组抗菌蛋白中有2条电泳带与对照组完全相同,但含量高于对照组;各诱导组与对照组比较均出现不同的新的蛋白带.结论家蝇幼虫诱导后产生的抗菌蛋白抗菌谱广;不同诱导源可诱导家蝇幼虫产生相同蛋白及不同的新蛋白.     

Protective effect of polypeptides from larva of housefly (Musca domestica) on hydrogen peroxide-induced oxidative damage in HepG2 cells

Housefly (Musca domestica) is an important medical insect and its larva is an ideal high protein food source. We isolated from housefly larvae the polypeptides hydrolyzed by neutral protease (PHNP), and investigated the protective effect of PHNP on hydrogen peroxide (H₂O₂)-induced oxidative damage in HepG2 cells. Cells exposed to H₂O₂ showed a marked decrease in proliferation and intracellular superoxide dismutase (SOD) activity, and a significant increase in reactive oxygen species (ROS) level and malondialdehyde (MDA) content. H₂O₂ also caused apoptosis and mitochondrial dysfunction including mitochondrial fragmentation and the loss of mitochondrial membrane potential. Pretreatment with PHNP at concentrations of 2.5, 5, 10 μg/mL blocked these H₂O₂-induced cellular events in a dose-dependent manner. The effect of PHNP at 10 μg/mL is equal to that of ascorbic acid at 10 μM. In summary, PHNP has a protective effect against H₂O₂-induced oxidative injury in cells due to its ability to decrease intracellular ROS and elevate antioxidant enzyme activities.     

阿苯达唑对感染仓鼠的美洲钩虫幼虫及虫卵的作用

感染美洲钩虫成虫的仓鼠口服阿苯达唑７５或１５０ｍｇ／ｋｇ的有效率为８３．８％和１００％。治前３ｄ，２个治疗组每鼠每ｇ粪便培养的幼虫数为２９７１６±３２９９和２８２５６±１１８，对照组的为８８２８±２６５９。治后３ｄ，治疗组的粪便培养未查见幼虫，而对照组的为９０６６±７４１６。此外，受治２组的培养粪便残渣用饱和盐水漂浮虫卵时，无或仅查见几个变性虫卵。仓鼠于感染第３期幼虫后３、７或１４ｄ口服１剂阿苯达唑１５０或３００ｍｇ／ｋｇ时，粪便虫卵阳性率为０－９．１％，减虫率为９６．８－１００％。     

烯虫酯对淡色库蚊幼虫剂量效应的实验研究

目的观察烯虫酯对淡色库蚊幼虫阶段的影响。方法采用浸渍法,观察蛹死亡和正常羽化情况。结果烯虫酯第7天致蛹死亡,LC50为2.165 8×10-8mg/ml,抑制蛹羽化作用的EC50为1.8105×10-8mg/ml;第11天致蛹死亡,LC50为1.949 4×10-8mg/ml,抑制蛹羽化作用的EC50为1.860 9×10-8mg/ml。结论烯虫酯影响淡色库蚊蛹到羽化阶段,可致蛹死亡,羽化率降低。     

Ovine vital neutrophil extracellular traps bind and impair Haemonchus contortus L3 in a breed‐dependent manner

This study aimed to characterize neutrophil response to Haemonchus contortus (Hc) in vitro using cells from parasite‐resistant St. Croix (STC) and parasite‐susceptible Suffolk (SUF) sheep. Neutrophils from Hc‐primed and naive STC and SUF sheep were incubated with Hc larval antigen (HcLA), Hc worm antigen (HcWA) or complete media (CM). After HcLA exposure, neutrophils from STC and SUF formed extracellular traps composed of DNA. Stimulation with HcLA induced a 35‐fold increase in extracellular DNA compared to CM controls. However, extracellular DNA was not found when neutrophils were cultured with HcWA. The formation of neutrophil extracellular traps (NET) in response to HcLA yields a low percentage of necrotic cells indicating a form of vital NETosis. Neutrophils from primed and naïve STC bound Hc L3 greater (93% and 68%) than SUF (78% and 45%; P < 0.001). Furthermore, STC neutrophils significantly reduced larval ATP levels compared to SUF neutrophils (0.05 μmol/L vs 0.1 μmol/L ATP, P < 0.001). These data indicate that ovine neutrophils bind, form vital NET and reduce ATP to Hc L3 in a breed and infection status–dependent manner.