Serological and molecular detection of infection with Mycobacterium leprae in Brazilian six banded armadillos (Euphractus sexcinctus)

Leprosy was recognized as a zoonotic disease, associated with nine-banded armadillos (Dasypus novemcinctus) in the Southern United States of America in 2011. In addition, there is growing evidence to support a role for armadillos in zoonotic leprosy in South America. The current study evaluated twenty specimens of the six-banded armadillo (Euphractus sexcinctus), collected from rural locations in the state of Rio Grande do Norte (RN), Brazil for evidence of infection with Mycobacterium leprae. Serum was examined using two "in-house" enzyme-linked immunosorbent assays (ELISAs) and via two commercially available (ML flow and NDO-LID®) immunochromatographic lateral flow (LF) tests, for detection of the PGL-I and/or LID-1 antigens of the bacterium. The presence of M. leprae DNA in liver tissue was examined using the multi-copy, M. leprae-specific repetitive element (RLEP), as target in conventional and nested PCR assays. Molecular and anti-PGL-I-ELISA data indicated that 20/20 (100 %) of the armadillos were infected with M. leprae. The corresponding detection levels recorded with the LF tests were 17/20 (85 %) and 16/20 (85 %), for the NDO-LID® and ML flow tests, respectively. Our results indicate that, in common with D. novemcinctus, six banded armadillos (a species hunted and reared as a food-source in some regions of Brazil, including RN), represent a potential reservoir of M. leprae and as such, their role in a possible zoonotic cycle of leprosy within Brazil warrants further investigation.     

凡纳滨对虾ARMC8基因的克隆及表达

为了研究含Armadillo重复蛋白8在凡纳滨对虾抗病感染过程中所起的免疫作用,本实验采用RACE-PCR技术首次克隆得到凡纳滨对虾ARMC8基因(LvARMC8,Gen Bank注册号:KX058562)的c DNA序列全长,并利用在线软件进行生物信息学分析;采用实时荧光定量PCR(Rt-PCR)技术对LvARMC8基因在凡纳滨对虾不同组织及感染白斑综合征病毒和副溶血弧菌过程中的表达变化特征进行分析。结果显示,LvARMC8基因全长为2917bp,其中开放阅读框长2046 bp,编码681个氨基酸,5′非编码区长49 bp,3′非编码区长822 bp。预测分析显示LvARMC8编码的蛋白质含有6个ARM结构域。同源性分析发现,LvARMC8基因与内华达古白蚁ARMC8基因的相似度最高,为71%。系统进化分析结果显示,LvARMC8和多种无脊椎动物ARMC8聚为一支,其中与昆虫类动物赤拟谷盗、致倦库蚊和柑橘凤蝶的亲缘关系最近。Rt-PCR分析发现,LvARMC8基因在凡纳滨对虾多个组织中均能检测出,在表皮中表达量最高,眼柄中表达量最低。WSSV感染后12 h,LvARMC8基因在凡纳滨对虾血液中的表达量显著降低,但48 h后显著升高,72 h达到最高水平。除副溶血弧菌感染后24 h外的时间点,LvARMC8基因在凡纳滨对虾血液中的表达量均显著升高。研究表明,LvARMC8基因可能参与凡纳滨对虾抗病免疫应答途径。     

Characterization of langerhans cells in epidermal sheets along the body of Armadillo (Dasypus novemcinctus)

Armadillos are apparently important reservoirs of Mycobacterium leprae and an animal model for human leprosy, whose immune system has been poorly studied. We aimed at characterizing the armadillo's langerhans cells (LC) using epidermal sheets instead of tissue sections, since the latter restrict analysis only to cut-traversed cells. Epidermal sheets by providing an en face view, are particularly convenient to evaluate dendritic morphology (cells are complete), spatial distribution (regular vs. clustered), and frequency (cell number/tissue area). Lack of anti-armadillo antibodies was overcome using LC-restricted ATPase staining, allowing assessment of cell frequency, cell size, and dendrites extension. Average LC frequency in four animals was 528 LC/mm(2), showing a rather uniform non-clustered distribution, which increased towards the animal's head, while cell size increased towards the tail; without overt differences between sexes. The screening of antibodies to human DC (MHC-II, CD 1a, langerin, CD86) in armadillo epidermal sheets, revealed positive cells with prominent dendritic morphology only with MHC-II and CD86. This allowed us to test DC mobilization from epidermis into dermis under topical oxazolone stimulation, a finding that was corroborated using whole skin conventional sections. We hope that the characterization of armadillo's LC will incite studies of leprosy and immunity in this animal model.     

Monitoring predators to optimize their management for marine turtle nest protection

The fundamental conservation focus for Hobe Sound National Wildlife Refuge (HSNWR), Florida is to provide protected nesting habitat for three threatened or endangered marine turtle species. Turtle nesting and hatching spans from early spring to fall each year. Left unchecked, nest predation by raccoons and armadillos would destroy most turtle nests. Predators are removed to protect nests, primarily with a one person-month contract using control specialists. We maximized the efficiency of predator removal by using a passive tracking index to: (1) optimize the timing and strategy for predator removal, (2) minimize labor by identifying areas where predator removal would have maximal effect, (3) examine beach invasion patterns of predators, (4) assess efficacy of removal efforts, (5) provide anticipatory information for future turtle nesting seasons, and (6) serve as a detection method for invasion by additional species known to depredate turtle nests. An overall nest predation rate of 28% resulted, whereas the rate for the previous year was 42% when the same level of contracted predator removal was applied, but without monitoring predators. One year before that, predator removal was done without contracts with specialists and predation was 48%. Up to 95% of the nests were destroyed in the years prior to predator removal. Using 2000 data on numbers of nests, clutch sizes, and emergence rates, we estimated the number of hatchlings that would have been lost assuming that the predation rates observed from four predator removal scenarios at HSNWR would have occurred in 2000. Historical predation of 95% would have resulted in 120,597 hatchlings lost in 2000. Predator removal as part of regular refuge operations would have reduced this number to 62,481. Addition of a contract with control specialists would have further reduced the number lost to 53,778. Addition of temporal and spatial monitoring for predator removal reduced losses to 36,637.     

纤维素合酶的组成以及蛋白间的相互作用

活细胞成像技术极大地加深了人们对纤维素沉积分子机制的理解.微管细胞骨架参与影响了纤维素合酶复合物的正常分布及其组织和动力学特征.随着纤维素合酶互动蛋白1（CSI1）的最新研究发现,纤维素微纤丝和微管间的关系十分紧密.CSI1是首个与纤维素合酶复合物相关联的非CESA蛋白,这给人们今后研究纤维素合酶开辟了许多新的机会.文中综述了纤维素合酶复合物（CSCs）的组成及纤维素蛋白间的相互作用.