Plasmodium berghei: a mouse model for the "sudden death" and "malarial lung" syndromes

A mouse model for the "sudden death" and "malarial lung" syndromes is described. Mice of the C3H/z strain succumb suddenly approximately 7 days after an infection with Plasmodium berghei becomes patent, at a time when parasitemia is still moderate (6 to 8%). Death could be shown to be due to anaphylactoid shock, probably induced by soluble immune complexes. Increased vascular permeability caused transudation and leakage of serum proteins into the interstitium and the alveoli. The lungs were found to be edematous, with a fine granular precipitate in the alveoli and adherent to the vascular walls. The precipitates reacted with antiglobulins G and M, and could be shown to also contain malaria antigens and C3/4. A dramatic drop in hematocrit was recorded several hours before death, indicating the sudden release of malaria antigens. The myocardium of animals that had died very suddenly showed a patchy loss of phosphorylase activity. This loss of activity was much more extensive, and sometimes almost total, when there had been an agonal period of several (1 to 3) hours before death. In these cases the irreversibility of the myocardial damage was also indicated by the loss of activity of the dehydrogenases, as well as by typical inflammatory reactions of granulocytic and histiocytic infiltrations. The hearts thus presented a typical picture of the acute and peracute shock syndromes. In acute shock cardiac insufficiency develops so suddenly that death ensues before irreversible damage has occurred, and cardiac insufficiency can only be demonstrated by the most sensitive of enzyme histochemical means. In the present case shock was induced by the anaphylactoid activity of immune complexes with the lung as target organ. The described syndrome appears analogous to human "malarial lung."     

辽宁省啮齿动物的地理区划

辽宁省的啮齿动物,过去曾在局部地区进行过调查(伍律等,1958;董谦等,1962;林兰泉等,1965),我站自1961年以来对全省作了较为全面的调查工作。关于啮齿动物的地理区划问题,肖增祜等(1978)曾作过区划拟议,将辽宁省初步划分为三个动物地理省(辽东山地丘陵省、辽西山地丘陵省、辽河平原省)。本文根据1958—1981年全省啮齿动物的调查资料,将辽宁省划分为五个啮齿动物地理省,现作如下叙述和讨论。     

Phylogeny of mitochondrial DNA clones in tassel-eared squirrels Sciurus aberti

The tassel-eared squirrel, Sciurus aberti , includes six subspecies which occupy restrictive and apparently identical habitats in Ponderosa pine forests in the south-western United States and Mexico; the strict habitat requirement of this species is based on dietary requirements which are only fulfilled in these forests. To examine evolutionary relationships among certain subspecies of S. aberti , we obtained estimates of nucleotide diversity within subspecies as well as nucleotide divergence between subspecies using mitochondrial DNA (mtDNA) analysis. Restriction site polymorphisms were identified in samples of the four US subspecies: S. a. aberti (Abert), S. a. kaibabensis (Kaibab), S. a. ferreus (Ferreus), and S. a. chuscensis (Chuska) Fourteen mtDNA clones were resolved that were, with one exception, uniquely subspecific. Dendrograms constructed by neighbour-joining and maximum parsimony methods revealed two major assemblages: (1) an Abert/Kaibab group; and (2) a Ferreus/Chuska group. The Abert vs. Ferreus clones exhibited the greatest net nucleotide divergence, with a lineage separation estimate approximating 572 000 years ago assuming a nucleotide substitution rate of 7.15 × 10^-9/year/site. Five out of ten Chuska squirrels shared a clone with one Abert sample; the relative sizes of these two populations and their respective ranges as well as their close proximity support the proposal for relatively recent intermixing of Abert and Chuska populations resulting in what appears to be Abert → Chuska migration. Nucleotide diversity within subspecies ranked as Kaibab < Ferreus < Abert < Chuska; the relatively high diversity for the Chuska sample is based on the apparent introgression of Abert mtDNA. The relative diversity exhibited by Kaibab, Ferreus and Aberti samples corresponds to the range size of the respective subspecies.     

多方法组合调查新疆阿勒泰地区6种常见鼠传致病菌流行状况

【背景】鼠传疾病是对人类危害较大的一种人兽共患病,全球化使得鼠传疾病流行区域不断扩大,出现了多种新发鼠传疾病的发生及旧传染病的复燃。【目的】调查新疆阿勒泰地区常见的鼠传致病菌在啮齿动物中的流行状况,为当地自然疫源性疾病防控提供科学依据。【方法】采用夹夜法捕获啮齿动物,无菌收集其脾脏和肾脏组织,提取基因组DNA。应用TaqMan探针法的荧光定量聚合酶链式反应(quantitative polymerase chain reaction, qPCR)检测巴尔通体(Bartonella spp.)、问号钩端螺旋体(Leptospirainterrogans)、恙虫病东方体(Orientiatsutsugamushi)、莫氏立克次体(Rickettsia mooseri)、嗜吞噬细胞无形体(Anaplasma phagocytophilum)和土拉弗朗西斯菌(Francisella tularensis)6种常见的鼠传致病菌。采用16SrRNA基因的通用引物进行常规PCR扩增后,应用Illumina测序和Nanopore测序进一步检测致病菌,同时对脾脏组织进行巴尔通体体外分离培养。比较qPCR...     

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ABSTRACT

In most mammals, adults produce relatively low frequency vocalizations compared to those of juveniles. This rule is not maintained however at least in four species of ground squirrels, whose juveniles call at the adult's fundamental frequency. These findings have been obtained however with separate sets of juveniles and adults and no data is available concerning the ontogeny linked to these differences. Here we analyze the acoustic structure of alarm calls of the same Yellow Spermophilus fulvus and Speckled S. suslicus ground squirrel individuals, recorded as pups and as adults after hibernation. We found the fundamental frequencies of adults within the same frequency ranges as those of pups, in spite of the significant difference in body mass. In ground squirrels, severing the relationship between body size and call frequency removes some vocal cues to age. We discuss some functional hypotheses advanced to explain manipulations with fundamental frequencies in ground squirrels and other animals, and suggest the lack of data for discussing the mechanisms of such vocal tuning.     

气候变化和经济发展对肾综合征出血热发生的影响

肾综合征出血热(hemorrhagic fever with renal syndrome, HFRS)是一种啮齿动物传播的自然疫源性疾病, 危害严重, 已成为全球重要的公共卫生问题。本研究采用数理统计模型及小波分析方法, 对陕西省西安市鄠邑区1984-2016年HFRS的发生与鼠类、气候和经济因素的关系进行分析, 探讨气候和经济因素对HFRS发生的影响。小波分析结果表明, 该地区的HFRS暴发史可能分为两个时期, 推测每个时期具有不同的主要宿主, 在2002年褐家鼠(Rattus norvegicus)可能取代黑线姬鼠(Apodemus agrarius)成为HFRS疫源地的主要宿主。广义可加模型模拟结果表明, HFRS的发生与1984-2001年黑线姬鼠密度间存在极显著非线性效应(F_2.06,9.02 = 102.415, P < 0.01), 两者间显现为正相关; 与2002-2016年的褐家鼠密度间呈正相关(F_1.67,9.02 = 73.929, P < 0.01); HFRS主要宿主的这种变化可能与当地气候变化和经济发展有关: HFRS的发生与年平均温度存在极显著的非线性效应(F_2.93,9.02 = 12.164, P < 0.01), 两者间呈负相关; 同样, HFRS的发生与上一年的国内生产总值(GDP)也存在显著非线性效应(F_1.70,9.02 = 2.917, P < 0.05), 两者间也呈负相关。结构方程模型通过直接和间接的影响途径证明了这种转移机制, 发现温度对HFRS发生有显著的直接负向影响以及通过褐家鼠的间接正向影响; GDP对HFRS发生有直接的负向影响。本研究表明HFRS的发生与气候变化和经济发展相关, 两者均能影响HFRS的暴发, 该结论有助于今后更好地对HFRS疾病进行预防和控制。     

新疆卡拉麦里山有蹄类野生动物自然保护区啮齿动物群落多样性及其与环境因子的关系

啮齿动物的群落结构受生态环境特征影响,并能反映环境变化规律。为探讨啮齿动物群落多样性及其与环境因子间的关系,利用铗捕法获得了新疆卡拉麦里山有蹄类野生动物自然保护区9种生境类型的环境因子及啮齿动物群落结构数据。2019-2020年春、夏季,共布设样地291块,有效铗日55269个,调查总面积176.875 km²,记录了啮齿类分布的12个环境因子。捕获啮齿动物419只,分属1目4科10属12种,优势种为三趾跳鼠（Dipus sagitta）和五趾跳鼠（Allactaga sibirica）,分别占捕获总个体数的34.13%和27.68%。分析结果显示,卡山自然保护区啮齿类捕获率最高的生境类型为沙漠（2.18%）;捕获鼠种的主要分布型为耐旱型（98.09%）。12个环境因子在9个生境类型中均呈极显著差异（P<0.01）,说明该保护区啮齿动物分布的生境异质性高。冗余分析表明,海拔高度、植被种类、灌木盖度和灌木高度是决定啮齿动物群落结构最主要的4个环境因子,其中植被种数与啮齿类群落多样性呈正相关,随着植被种数数值的增加,除优势度指数外,其它多样性指数随之增加。