IL-18 stimulates IL-13-mediated IFN-gamma-sensitive host resistance in vivo

IL-4 and IL-13 are up-regulated during in vivo responses to many nematode parasites, but increasing evidence suggests that increases in IL-13 can also occur independently of the IL-4-dominant Th2 response. Blocking B7 after Trichuris muris inoculation inhibits resistance and IL-4 elevations, instead resulting in an IFN-gamma-dominant response associated with susceptibility. However, blocking IFN-gamma under these conditions restores IL-13-dependent resistance. In this study, we examined the mechanism of IL-13 up-regulation and associated protection during this in vivo immune response. CD4+ T cells and DX5+ TCR- cells were identified as the major producers of IL-13, and the DX5+ TCR- cells were phenotyped as NK cells, since they expressed CD11b, IL-2Rbeta and Ly49C but not c-kit or Fc epsilonRI. NK cell-derived IL-13 elevations were T cell-dependent, as CD4+ T cell depletion blocked IL-13 production by mesenteric lymph node cells and induced susceptibility. IL-13 expression was increased independently of IL-12; however, blocking IL-18 function inhibited IL-13 production and increased susceptibility. These results indicate that CD4+ T cells and NK cells are the major sources of IL-13 during the in vivo Th1 response induced by B7 blockade and that under these conditions, IL-18 is specifically required for the in vivo up-regulation of IL-13 production and associated host protection.     

Rickettsia felis: from a rare disease in the USA to a common cause of fever in sub-Saharan Africa

Rickettsia felis is a spotted fever group rickettsia that has been definitely described in 2002. Within the last 20 years, there have been a growing number of reports implicating R. felis as a human pathogen, parallel to the fast-growing reports of the worldwide detection of R. felis in arthropod hosts, mainly the cat flea Ctenocephalides felis felis. R. felis is now known as the agent of the so-called flea-borne spotted fever, with more than 70 cases documented in the literature. Recently, two studies respectively conducted in Senegal and Kenya, have challenged the importance of R. felis infection in patients with unexplained fever in sub-Saharan Africa. We focus here on the epidemiological and clinical aspects of R. felis infection. More studies are needed, including the study of other arthropod vectors, but it can be speculated that R. felis infection might be an important neglected agent of fever in sub-Saharan Africa.     

胎儿骶尾部寄生胎合并畸胎瘤1例

正孕妇,23岁,孕1产0,孕20+6周,因唐氏筛查结果为唐氏高风险而需羊水穿刺检查,穿刺前接受产前常规超声检查。二维超声发现胎儿骶尾部囊实性占位,12.1cm×8.7cm×11.8cm,以实性成分为主,团块内见多个点状强回声,后方伴声影,团块明显凸向羊膜腔(图1);CDFI示团块内较丰富血流信号(图1C),羊水量未见异常。超声诊断:胎儿骶尾部畸胎瘤可能性大。孕22+3周超声复查示胎儿骶尾部团块大小为     

温度对豫南罗索线虫寄生前期幼虫存活力和感染力的影响

应用定量的方法，对豫南罗索线虫寄生前期幼虫在不同温度下的存活力和感染力进行系统观测。结果：在一２℃～２℃下，９０％以上的幼虫可存活８天，并保持相当强的感染力。在２６℃～２８℃和１６℃～１８℃下，９０％的存活时间分别为２４小时和４８小时。结果表明，一２℃～２℃低温贮存的方法可延长该幼虫的寿命，并保持其感染力。     

感染性疾病研究新进展述评及展望

感染性疾病是临床常见且重要的疾病,事关国家安全和人民健康。目前感染性疾病防治研究水平虽不断提高,但感染病防控形势依然严峻。为了让广大医疗工作者了解当前感染性疾病研究新进展,本文介绍了病毒性感染、细菌性感染、真菌性感染及寄生虫感染等重要感染性疾病的现状,对感染病相关领域的研究与防治进展做一述评,并对将来可能的重点研究方向进行展望,以期提高我国感染性疾病研究水平。