Effect of Acanthocephala infection on the reproductive potential of crustacean intermediate hosts

The effect of a naturally acquired infection by three acanthocephalan parasites Dentitruncus truttae, Echinorhynchus truttae, and Polymorphus minutus on the reproductive potential of their intermediate host, Echinogammarus tibaldii (Amphipoda) from Lake Piediluco (Centre of Italy) was assessed. During May 2007, 1135 amphipods were collected from two different samplings and examined for larval helminths. Forty-five amphipods were infected and of those, 16 were infected with D. truttae (intensity = 1-3 larvae), 15 with E. truttae (intensity = 1-2 larvae), and 14 with P. minutus (intensity = 1 larva). The sex ratio was nearly 1:1 in all examined amphipods. One female infected with D. truttae contained six eggs in the brood pouch and another female infected with E. truttae contained five eggs. However, none of the eight female amphipods harbouring P. minutus larva contained eggs in their brood pouch. Uninfected females of the same size and body length as that of the infected females contained between 20 and 32 eggs. No acanthocephalan species were found to co-occur.     

Transforming growth factor-beta and insulin-like signalling pathways in parasitic helminths

The signal transduction pathways involved in regulating developmental arrest in the free-living nematode, Caenorhabditis elegans, are fairly well characterised. However, much less is known about how these processes may influence the developmental timing and maturation in helminth parasites. Here, we provide an overview of two signalling pathways implicated in the regulation of dauer larva formation in C. elegans, the insulin-like signalling pathway and the transforming growth factor-beta pathway, and explore what is known about these signalling pathways in a variety of parasitic helminths. Understanding the differences about how these pathways are affected by environmental cues in free-living versus parasitic species of helminths may provide insights into novel mechanisms for the control or prevention of helminth-induced disease.     

Trichinella spiralis: recognition of muscle larva antigens during experimental infection of swine and its potential use in diagnosis

Longitudinal studies with Trichinella spiralis experimentally infected pigs were carried out to identify muscle larva antigens recognized during infection. This was approached using Western blot analysis and ELISA assays. Immunoblots of sera from experimentally infected pigs using total parasite extracts revealed five principal parasite antigens throughout infection. A similar pattern of antigen recognition was given by sera from backyard pigs in areas of Mexico, some of them endemic for Trichinella. Four of the five antigens recognized (MW 47, 52, 67, and 72 kDa) corresponded to surface/stichosomal antigens purified by monoclonal antibody NIM-M1. In addition, Western blots of excretions-secretions of muscle larva contained three (MW 52, 67, and 72 kDa) of the four surface/stichosomal components recognized by NIM-M1. Affinity-purified surface/stichosomal components, total soluble extracts, and excretory-secretory antigens of muscle larva were then evaluated in ELISA for detection of T. spiralis infections in experimentally infected, noninfected control, and 295 backyard pigs. These assays showed that purified surface/stichosomal components and excretory-secretory antigens increased the specificity of ELISA. These results suggest that muscle larva components purified by monoclonal antibody NIM-M1 are the major antigens recognized during infection of pigs with T. spiralis and therefore potentially useful for diagnosis of swine trichinellosis.     

转Bt基因抗虫棉对亚洲玉米螟抗性的研究

对转Bt抗虫棉苏抗103与GK—22对玉米螟抗性的研究结果显示：(1)用苏抗103嫩叶、簧,花、蕾饲曩第三代玉米螟幼虫,最终幼虫校正死亡率分别达100％、95．83％、83．33％与100％。校正化蛹下降率分别达100％、92．31％、50．07％与100％,校正幼虫成蛾减退率分别达100％、90．92％、0％与100％。(2)人工饲料中加入5个不同浓度苏抗103嫩叶饲喂第二代幼虫,除0．4％浓度,幼虫校正死亡率与成蛹下降率均为100％,0．4％浓度的幼虫期延长20．68％,蛹重下降18．24％,蛹期延长19．79％。(3)人工饲料中加入5个浓度的苏抗103或GK22嫩叶分别饲喂第三代幼虫,苏抗103上幼虫校正死亡率较第二代有所下降,分别为3．04％、-16．68％、28．2％、33．33和75％。GK22上幼虫校正死亡率分别为3．13％、26．89％、45．69％、70．816％和68．09％。其幼虫校正死亡率及幼虫期、蛹期、成虫校正减退率均有随浓度增加而上升的趋势。较亲本棚,对蛹重、雌成虫寿命、单雌产卵量、卵孵化率也有一定程度的影响。上述研究结果表明,苏抗103与GK22影响棉田玉米螟幼虫与蛹的存活与生命力,进而影响其成虫繁殖力而表现出良好抗性。     

洋虫营养成分分析

分析洋虫Palembus dermestoides(Fairmaire)成、幼虫体内的营养成分,并对氨基酸的质量进行了评价。结果表明:洋虫成虫和幼虫都具有丰富的营养,其中粗蛋白48.31%和54.94%、粗脂肪17.64%和18.24%、粗灰分3.0%和2.8%、总糖31.05%和24.08%,TAA为39.03 g/100 g和47.4 g/100 g、EAA/TAA为46.29%和47.14%,含有丰富的矿物质和微量元素,尤其是Zn的含量达到101.00 mg/kg和186.00 mg/kg,且不含有对人体有害的Cd,Hg,Pb。对幼虫进行氨基酸评价,其必需氨基酸指数为114.71。与目前常见的蛋白源相比较,洋虫是一种高蛋白、低脂肪、氨基酸含量较全面且富含矿物质和微量元素的昆虫资源。     

中国畜禽粪便污染现状及产沼气潜力

为弄清中国畜禽粪便排放总量、污染现状及其资源化潜力,通过查阅文献确定了主要估算参数,并结合畜牧业统计数据估算了2009年中国畜禽粪便排放量及其污染物含量、粪便农用地负荷并对畜禽粪便中氮、磷农用地负荷进行预警分级;同时估算了粪便资源沼气潜力。结果表明:2009年中国畜禽养殖业粪便排放总量为32.64亿t鲜重,其中BOD、COD含量分别为7273.95和8039.96万t。全国单位面积农用地畜禽粪便负荷为26.8t·hm-2,氮、磷素负荷分别为158.42和47.92kg·hm-2。预警分级显示:牧区畜禽养殖业对环境不构成威胁;农区除山西、黑龙江外,其他地区均出现不同程度的氮素污染,而磷素的影响在农区普遍存在。2009年畜禽粪便资源沼气潜力约1200亿m3,其中,大中型畜禽养殖场沼气潜力为240亿m3,约合天然气135亿m3。目前沼气工程已成为环境保护和能源结构调整的一种重要手段。     

Distribution of zinc in parasitic helminths

The distribution of zinc in representative groups of parasitic helminths was determined by the use of the atomic absorption spectrophotometer. The results of these analyses have shown that growing flukes (smaller forms) with active oogenesis and spermatogenesis contained more zinc than old (large) or very old adults with an empty uterus and large lobulated testes. In cestodes, the neck region and immature proglottids showed more zinc concentration than mature and gravid proglottids and fully grown cyst walls. Similarly, the youngest endogenous daughter cysts of Echinococcus granulosus contained more zinc in their walls than those of larger/older forms. Zinc was concentrated more in nematode eggs than in adult females.     

Socio-medical studies of individuals self-treating with helminths provide insight into clinical trial design for assessing helminth therapy

The virtually complete loss of intestinal worms, known as helminths, from Western society has resulted in elimination of a range of helminth-induced morbidities. Unfortunately, that loss has also led to inflammation-associated deficiencies in immune function, ultimately contributing to widespread pandemics of allergies, autoimmunity, and neuropsychiatric disorders. Several socio-medical studies have examined the effects of intentional reworming, or self-treatment with helminths, on a variety of inflammation-related disorders. In this study, the latest results from ongoing socio-medical studies are described. The results point toward two important factors that appear to be overlooked in some if not most clinical trials. Specifically, (a) the method of preparation of the helminth can have a profound effect on its therapeutic efficacy, and (b) variation between individuals in the effective therapeutic dosage apparently covers a 10-fold range, regardless of the helminth used. These results highlight current limits in our understanding of the biology of both hosts and helminths, and suggest that information from self-treatment may be critical for clinical evaluation of the benefits and limits of helminth therapy.     

Helminth Colonization Is Associated with Increased Diversity of the Gut Microbiota

Soil-transmitted helminths colonize more than 1.5 billion people worldwide, yet little is known about how they interact with bacterial communities in the gut microbiota. Differences in the gut microbiota between individuals living in developed and developing countries may be partly due to the presence of helminths, since they predominantly infect individuals from developing countries, such as the indigenous communities in Malaysia we examine in this work. We compared the composition and diversity of bacterial communities from the fecal microbiota of 51 people from two villages in Malaysia, of which 36 (70.6%) were infected by helminths. The 16S rRNA V4 region was sequenced at an average of nineteen thousand sequences per samples. Helminth-colonized individuals had greater species richness and number of observed OTUs with enrichment of Paraprevotellaceae, especially with Trichuris infection. We developed a new approach of combining centered log-ratio (clr) transformation for OTU relative abundances with sparse Partial Least Squares Discriminant Analysis (sPLS-DA) to enable more robust predictions of OTU interrelationships. These results suggest that helminths may have an impact on the diversity, bacterial community structure and function of the gut microbiota.     

Acid proteinases of the fore-gut in metamorphosing tadpoles of Rana catesbeiana.

1. Two types of acid proteinases were found in the adult stomach of the bullfrog, Rana catesbeiana. 2. The first type of enzyme appeared in the developing stomach and esophagus and contained more than two kinds of acid proteinases. 3. These enzymes were identified as pepsin-type enzymes. 4. The second type of enzyme existed from the larva to adult stage and was also present in the adult duodenum. 5. This enzyme was different from pepsin and thought to be cathepsin E.     

不同改良方法对盐碱土壤氮素营养状况的影响

采用浅耕翻、施用磷石膏、施用糠醛渣、施用有机肥、建植星星草人工草地或星星草+羊草人工草地等不同改良方法对盐碱土壤氮素营养影响的研究结果表明,不同改良方法与浅耕翻相比能不同程度地提高土壤全氮含量、碱解氮含量、氨化强度、固氮强度、蛋白酶活性、脲酶活性、硝酸还原酶活性和亚硝酸还原酶活性。其中,浅耕+有机肥+星星草+羊草处理对所测定盐碱土壤氮素营养及相关酶活性指标增加明显,同时,盐碱土壤氮素营养各指标间存在着一定的相关关系。     

Expression of Lex antigen in Schistosoma japonicum and S.haematobium and immune responses to Lex in infected animals: lack of Lex expression in other trematodes and nematodes

Adults of the human parasitic trematode Schistosoma mansoni, which causes hepatosplenic/intestinal complications in humans, synthesize glycoconjugates containing the Lewis x (Lex) Galbeta1-->4(Fucalpha1-- >3)GlcNAcbeta1-->R, but not sialyl Lewis x (sLex), antigen. We now report on our analyses of Lexand sLexexpression in S.haematobium and S.japonicum, which are two other major species of human schistosomes that cause disease, and the possible autoimmunity to these antigens in infected individuals. Antigen expression was evaluated by both ELISA and Western blot analyses of detergent extracts of parasites using monoclonal antibodies. Several high molecular weight glycoproteins in both S. haematobium and S. japonicum contain the Lexantigen, but no sialyl Lexantigen was detected. In addition, sera from humans and rodents infected with S.haematobium and S.japonicum contain antibodies reactive with Lex. These results led us to investigate whether Lexantigens are expressed in other helminths, including the parasitic trematode Fasciola hepatica , the parasitic nematode Dirofilaria immitis (dog heartworm), the ruminant nematode Haemonchus contortus , and the free-living nematode Caenorhabditis elegans . Neither Lexnor sialyl-Lexis detectable in these other helminths. Furthermore, none of the helminths, including schistosomes, express Lea, Leb, Ley, or the H- type 1 antigen. However, several glycoproteins from all helminths analyzed are bound by Lotus tetragonolobus agglutinin , which binds Fucalpha1-->3GlcNAc, and Wisteria floribunda agglutinin, which binds GalNAcbeta1-->4GlcNAc (lacdiNAc or LDN). Thus, schistosomes may be unique among helminths in expressing the Lexantigen, whereas many different helminths may express alpha1,3-fucosylated glycans and the LDN motif.      

Helminth fauna in small rodents (Mammalia: Rodentia) of canal banks in meliorated territories

A helminth fauna of small rodents inhabiting channel banks have been investigated in soil improvement territories (Belorussian Polesie) in the period 1996-1999. 41 helminth species have been found in animals. Generally, there are specific helminths of rodents of the Cricetidae and Muridae families. These animals also participate in life cycles of bird's and carnivore's helminths.     

Coprological study on helminth fauna in Eurasian lynx (Lynx lynx) from the Białowieza Primeval Forest in eastern Poland

One hundred fecal samples were collected during research on Eurasian lynx ecology and food habits in the Polish part of the Bia?owieza Primeval Forest (BPF) from 2001 to 2006. Seventy-three percent of samples contained eggs or larvae of helminths. A total of 10 species of helminths was identified, including 3 Cestoda (Diphyllobothrium latum, Spirometra janickii, and unidentified species of Taeniidae), 1 Trematoda (Alaria alata), and 6 Nematoda (Aelurostrongylus abstrusus, Ancylostoma tubaeforme, Eucoleus aerophilus, Metastrongylus sp., Nematodirus sp., and Toxocara cati). Alaria alata has not been reported previously in lynx. A statistical comparison of the 2 techniques used to isolate eggs, i.e., flotation and sedimentation, indicates that sedimentation was more effective.     

大头金蝇营养成分分析

分析大头金蝇Chrysomya megacephala(Fabricius)的营养成分。结果表明,大头金蝇幼虫、蛹、成虫干粉水分含量分别是6.83,2.07和3.70%,干体粗蛋白含量分别为63.72,76.81和70.54%,粗脂肪分别为16.43,12.82和7.23%。蛋白质中氨基酸总量百分比分别为56.39,55.61和59.12%,其中必需氨基酸占氨基酸总量(E%)的48.34,53.08和43.91%,必需氨基酸与非必需氨基酸之比(E/N)分别为0.94,1.13,0.81,E/T为3.22,3.54,2.93。大头金蝇幼虫、蛹、成虫不饱和脂肪酸占总脂肪酸含量依次是68.1,61.9和65.9%。含有人和动物所必需的常量和微量元素,但没有检测到有毒重金属镉(Cd)、铅(Pb)。大头金蝇与鱼粉、舍蝇幼虫、柞蚕蛹相比,营养成分指标较高,属于理想的昆虫蛋白资源。     

Bacterial fora of patients treated with bleomycin]

Microflora of the pharynx, nose, sputum and excrements was investigated. It was found that bleomycin therapy may induce or aggravate the shifts in microbiocenosis of the pharynx and sputum in the direction of pathogenization (increase in the number of Staph. aureus, hemolytic streptococci, enterobacteria). A tendency to elimination of bifidobacteria and appearance of Proteus in the excrements was observed. Complications associated with the treatment are rarely of infectious origin.     

苏云金芽孢杆菌的一个新亚种(Btsubsp.sinensis)

198 9年自云南昆明市石林的红棕壤中分离到数株苏云金芽孢杆菌 (Ｂａｃｉｌｌｕｓｔｈｕｒｉｎｇｉｅｎ ｓｉｓ,Ｂｔ)菌株[1] ,对其中的一株ＹＫ30 0 4进行了生物学特性、杀虫特性研究及分类鉴定。1　材料与方法1.1　供鉴定的Ｂｔ菌株由云南昆明市石林的红棕壤中分离的苏云金芽孢杆菌ＹＫ30 0 4菌株。1.2　标准Ｂｔ菌株血清型Ｈ1 Ｈ4 1、Ｈ4 4 Ｈ55及Ｈ57 Ｈ69标准Ｂｔ菌株由法国巴斯德研究院ＤｒＬｅｃａｄｅｔ提供 ,其余为本实验室保存。1.3　生物测定用昆虫小菜蛾 (Ｐｌｕｔｅｌｌａｘｙｌｏｓｔｅｌｌａ) 3龄幼虫 ;斜纹夜盗蛾 (Ｐｒ…     

Chemical cues from Spodoptera litura larvae elicit prey-locating behavior by the predatory stink bug, Eocanthecona furcellata

Two chemical compounds eliciting prey-locating behavior of the predatory stink bug, Eocanthecona furcellata, were isolated from solvent extracts of Spodoptera litura larvae and identified. A hexane eluted fraction from silica gel chromatography of the solvent extracts of S. litura larvae was attractive to E. furcellata nymphs when assayed with a linear track olfactometer. The hexane fraction was found to contain n-pentadecane (2500 ng/larva), n-tetracosane (54 ng/larva), n-heptadecane (41 ng/larva), n-heptacosane (61 ng/larva), n-nonacosane (147 ng/larva), n-hentriacontane (200 ng/larva) and squalene (323 ng/larva). The synthetic n-pentadecane was attractive to the bugs, although its activity was slightly lower than that of the hexane fraction. A mixture of synthetic n-pentadecane and the other six hydrocarbons was also attractive, although no improved attractiveness was observed by the addition of the latter compounds. On the other hand, a 15%-ether-in- hexane eluted fraction from silica gel chromatography stimulated bugs to display a proboscis-protruding behavior. A neutral-layer fraction of the 15% fraction, which contained E-phytol (480 ng/larva), also elicited this behavior. Synthetic E-phytol had the same effect on the predators as the neutral-layer fraction.     

唐家河自然保护区大熊猫种群数量及栖息地的移动

本文根据大熊猫季节性活动规律特点,应用海拔高度路线调查法,全面收集唐家河自然保护区大熊猫的比较新鲜粪便,计获１２４个粪样材料,提取ＤＮＡ作ＤＮＡ指纹图,经微机检测,保护区有大熊猫３７只,个体数量与粪样采集量之比为１∶３３５１４,有６个家系,雌兽２１只,雄兽１６只。并搞清了保护区生态环境质量,箭竹遭受病虫害的程度,洪水对栖息地的影响,特别对引起大熊猫数量减少及栖息地移动等原因,作了较为详细的分析。