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DA Rosa AC Lessinger AC DE Azeredo-Espin AM Torres TT 《Molecular ecology resources》2008,8(5):971-973
The horn fly, Haematobia irritans (L.) (Diptera: Muscidae), is a cosmopolitan livestock pest that has caused a great negative impact on the animal production sector throughout the world. Here, we describe 10 polymorphic microsatellite loci isolated from H. irritans. The number of alleles found ranged from two to eight per locus and the expected heterozygosity from 0.1421 to 0.7702. These loci are potentially useful for the fine-scale genetic characterization of horn fly populations and provide fundamental information for pest management and planning of control programs. 相似文献
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GUO XING ZHONG JUN DA SU QING WEN SUN BING HUA JIAO Department of Biochemistry Molecular Biology Second Military Medical University Shanghai School of Life Sciences Medical Engineering Tongji University Shanghai China Shangha 《Cell research》2001,(4)
INTRODUCTIONEstrogen has been known to exert extensive effects via estrogen receptor (ER) on diverse physio-logical and develoPmental functions of the brain[1,2]. It has been observed that the distribution ofthe classical ER subtype-a (ERa) and the recentlycharacterized novel ER subtype--fi (ERg), and theirexpression patterns (ERcr/ERfi) vary greatly amongvarious brain regions[1, 3]. These evidences suggestthat each ER subtype may play a different role inestrogen's effects on the br… 相似文献
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A procedure has been developed for estimating the survival time of short-lived alkylating agents in a flow system at physiological temperature and pH. The system simulated the slow release into the bloodstream of a reactive compound formed in the liver. A solution of the reactive compound was injected slowly into a fast stream of aqueous fluid and immediately mixed. After a delay (up to 1 min) determined by a length of tube, during which hydrolysis took place, the surviving reactive compound was trapped on a column of immobilized thiol (thiol-Sepharose), and the fluid was recirculated via a reservoir. The system was used to study the hydrolysis of the pyrrolizidine alkaloid metabolites dehydromonocrotaline, dehydro-anacrotine and dehydroretrorsine. The S-bound pyrrolic moiety in the trap was measured colorimetrically and hydrolysis rates were estimated after a series of 1-h runs with different delay times. Hydrolysis of dehydroretrorsine was very rapid, whereas the hydrolysis of dehydromonocrotaline and dehydro-anacrotine fitted biphasic first-order reactions, with a faster first phase. By isolating and identifying the trapped products from dehydromoncrotaline it was shown that the two phases involved hydrolysis of the 7- and 9-ester groups, respectively. The results supported the view that a proportion of the reactive metabolites from the alkaloids monocrotaline and anacrotine would be able to survive long enough to be transported from the liver to the lungs of a rat. The flow system would be applicable to the study of other types of short-lived metabolites. 相似文献
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Studies on myosin-azomercurial complexes 总被引:2,自引:0,他引:2
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G.E. Neal A.R. Mattocks D.J. Judah 《Biochimica et Biophysica Acta (BBA)/General Subjects》1979,585(1):134-142
The activation by rat liver microsomal systems in vitro of a naturally occurring and a synthetic furan-containing toxin, aflatoxin B1 and 2-(N-ethylcarbamoyloxymethyl)furan (CMF) has been examined. Both compounds are metabolised to form products which bind covalently to DNA and microsomal protein, Using a specially designed two-chamber diffusion apparatus it has been demonstrated that the active metabolite of CMF is able to bind covalently to DNA separated by a membrane barrier from the microsomal site of activation. In the case of aflatoxin B1 the DNA must be in physical contact with the microsomal system for the active metabolite of aflatoxin B1 to bind covalently. Differences between the activation of the two compounds have also been found with regard to their relative efficiencies in binding to DNA and also the effects of the nucleophile GSH. These results have suggested that if the molecular mechanisms of activation of the two compounds be similar, other factors, for example differences in lipid solubility, may play important roles in determining the relative biological activaties of the compounds. The results suggested that the subcellular site of activation of aflatoxin B1, unlike that of CMF, may need to be adjacent to the target DNA. It is proposed that this site might be the outer nuclear membrane. Alternatively a carrier molecular might exist for the activated aflatoxin B1 metabolite in vivo. 相似文献
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C. PRADO E CASTRO A. SERRANO P. MARTINS DA SILVA M. D. GARCÍA 《Medical and veterinary entomology》2012,26(4):417-431
Information on Diptera community, seasonality and successional patterns in every geographical region is fundamental for the use of flies as forensic indicators of time of death. In order to obtain these data from the Lisbon area (Portugal), experiments were conducted during the four seasons of the year, using piglet carcasses as animal models. Five stages were recognized during the decomposition process. The stages, besides visually defined, could be separated taking into account the occurrence and abundance of the specific groups of Diptera collected. In general, the bloated stage recorded higher abundance and species‐richness values. Seventy‐one species were identified, belonging to 39 families, in a total of 20 144 adult Diptera collected. Autumn yielded the highest values of species richness, whereas winter had the lowest. In all seasons of the year, Calliphoridae was the dominant family; Muscidae and Fanniidae were very abundant as well. Calliphora vicina Robineau‐Desvoidy, Calliphora vomitoria (Linnaeus), Chrysomya albiceps (Wiedemann), Lucilia ampullacea Villeneuve, Lucilia caesar (Linnaeus), Lucilia sericata (Meigen) (Calliphoridae), Hydrotaea ignava (Harris), Muscina prolapsa (Harris), Synthesiomyia nudiseta (van der Wulp) (Muscidae), Piophila megastigmata McAlpine, Stearibia nigriceps (Meigen) (Piophilidae) and Nemopoda nitidula (Fallén) (Sepsidae) were revealed to be very important members of the Diptera community collected. The necrophagous behaviour, demonstrated by their immatures, using carrion as a food source makes them useful forensic indicator species. Also of relevance is the presence of Chrysomya megacephala (Fabricius), S. nudiseta and P. megastigmata, foreign species established in the local carrion communities. This study also marks the first record of S. nudiseta in Portugal. 相似文献
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The acrosome of the spermatozoa is the organelle involved in its penetration through the ova membranes during the fertilization process. Several features of this process are considered to be related to the fertilization events e.g. some substance coats outside the membrane. During the maturation process the spermatozoa of Conocephalus saltator develop a coat of tubules and filaments which overly some membrane regions in a specific array. The mature spermatozoa are seen to adhere in these regions and form threads of 20 cells long and five to six wide. It is suggested that the external coat plays a role in this 'sticking' phenomenon. 相似文献