Do tree species affect decadal changes in soil organic carbon and total nitrogen stocks in Danish common garden experiments?     

Christina Steffens  Christian Beer  Stephanie Schelfhout  An De Schrijver  Eva-Maria Pfeiffer  Lars Vesterdal 《European Journal of Soil Science》2022,73(1):e13206

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Limitations of sandwich ELISAs for bluetongue virus antibody detection     

Eschbaumer M  Schulz C  Wäckerlin R  Gauly M  Beer M  Hoffmann B 《The Veterinary record》2011,168(24):643

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Production of Galacto-oligosaccharides by the β-Galactosidase from Kluyveromyces lactis : comparative analysis of permeabilized cells versus soluble enzyme     

Rodriguez-Colinas B  de Abreu MA  Fernandez-Arrojo L  de Beer R  Poveda A  Jimenez-Barbero J  Haltrich D  Ballesteros Olmo AO  Fernandez-Lobato M  Plou FJ 《Journal of agricultural and food chemistry》2011,59(19):10477-10484

The transgalactosylation activity of Kluyveromyces lactis cells was studied in detail. Cells were permeabilized with ethanol and further lyophilized to facilitate the transit of substrates and products. The resulting biocatalyst was assayed for the synthesis of galacto-oligosaccharides (GOS) and compared with two soluble β-galactosidases from K. lactis (Lactozym 3000 L HP G and Maxilact LGX 5000). Using 400 g/L lactose, the maximum GOS yield, measured by HPAEC-PAD analysis, was 177 g/L (44% w/w of total carbohydrates). The major products synthesized were the disaccharides 6-galactobiose [Gal-β(1→6)-Gal] and allolactose [Gal-β(1→6)-Glc], as well as the trisaccharide 6-galactosyl-lactose [Gal-β(1→6)-Gal-β(1→4)-Glc], which was characterized by MS and 2D NMR. Structural characterization of another synthesized disaccharide, Gal-β(1→3)-Glc, was carried out. GOS yield obtained with soluble β-galactosidases was slightly lower (160 g/L for Lactozym 3000 L HP G and 154 g/L for Maxilact LGX 5000); however, the typical profile with a maximum GOS concentration followed by partial hydrolysis of the newly formed oligosaccharides was not observed with the soluble enzymes. Results were correlated with the higher stability of β-galactosidase when permeabilized whole cells were used.  相似文献   

Detection of Usutu virus in a bullfinch (Pyrrhula pyrrhula) and a great spotted woodpecker (Dendrocopos major) in north-west Europe     

Mutien-Marie Garigliany  Didier Marlier  Klara Tenner-Racz  Martin Eiden  Dominique Cassart  Frédéric Gandar  Martin Beer  Jonas Schmidt-Chanasit  Daniel Desmecht 《Veterinary journal (London, England : 1997)》2014,199(1):191-193

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Evaluating the protective efficacy of a trivalent vaccine containing Akabane virus,Aino virus and Chuzan virus against Schmallenberg virus infection     

Silke Hechinger  Kerstin Wernike  Martin Beer 《Veterinary research》2013,44(1):114

Schmallenberg virus (SBV), an arthropod borne pathogen, spread rapidly throughout the majority of Europe since 2011. It can cause a febrile disease, milk drop, diarrhea, and fetal malformation in ruminants. SBV, a member of the Simbu serogroup within the genus Orthobunyavirus, is closely related to Akabane virus (AKAV) and Aino virus (AINOV) among others. In the present study, 4 Holstein-Friesian calves were immunized twice four weeks apart with a multivalent, inactivated vaccine against AKAV and AINOV. Another 4 calves were kept as unvaccinated controls. All animals were clinically, serologically and virologically examined before and after challenge infection with SBV. AKAV- and AINOV-specific neutralizing antibodies were detected one week before challenge infection, while SBV-specific antibodies were detectable only thereafter. SBV genome was detected in all vaccinated animals and 3 out of 4 controls in serum samples taken after challenge infection. In conclusion, the investigated vaccine was not able to prevent an SBV-infection. Thus, vaccines for other related Simbu serogroup viruses can not substitute SBV-specific vaccines as an instrument for disease control.  相似文献   

Lectin‐Binding Pattern in Ovarian Structures of Rats with Experimental Polycystic Ovaries     

CG Barbeito  HH Ortega  V Matiller  EJ Gimeno  NR Salvetti 《Reproduction in domestic animals》2013,48(5):850-857

Numerous experimental models in different species have been developed for the study of polycystic ovarian syndrome. In this study, we used a model of induction of polycystic ovaries (PO) in rats by exposure to constant light to study the distribution and variations of glycosylated residues present in the different ovarian structures. Seven biotinylated lectins were used (Con‐A, WGA, DBA, SBA, PNA, RCA and UEA‐I) on tissue sections, and detection was performed using the streptavidin/peroxidase method. In tissue sections was observed an increase in affinity for Con‐A in the granulosa and theca interna of growing follicles and cysts in animals with PO in relation to the control group. Follicular cysts showed higher affinity for WGA and RCA‐I which growing follicles in the same group, and there was a decrease in affinity for PNA in the cysts in relation to the growth of follicles in both groups. Atretic follicles in both groups showed greater labelling with lectins PNA, SBA and RCA‐I in relation to healthy follicles. It could also be noted that the zona pellucida of cystic follicles lost the affinity for the lectin Con‐A. There was no staining on follicles in any category with the lectins DBA and UEA‐I, although it was staining in the corpus luteum (control group) and in the mesothelium and interstitial glands of both groups with DBA. These observations probably reflect changes in the glycosaminoglycans present in the different ovarian compartments or in the glycosylation of cellular components essential for proper follicular dynamics.  相似文献   

Production of Oocytes of Nile Tilapia (Oreochromis niloticus) for In Vitro Fertilization via Hormonal Treatments     

DAA Oliveira  CG Aleixo  SA Prado  RK Luz  NLAF Sarmento  EA Teixeira  MR Luz  EM Turra 《Reproduction in domestic animals》2013,48(6):1049-1055

Only a few studies have described hormonal treatments for induction of synchronicity and gamete collection in Nile tilapia (Oreochromis niloticus), both important for assortative matings in breeding programmes and essential for polyploidy technologies. In this study, we compared the effectiveness of carp pituitary extract (CPE), Nile tilapia pituitary extract (TPE), human chorionic gonadotropin (hCG) and gonadotropin‐releasing hormone (GnRH) protocols on the induction of spawning and egg production in Nile tilapia. Among the hormonal treatments analysed, only hCG was effective for producing viable gametes for in vitro fertilization. To verify the viability of this hormonal treatment, hCG was tested using different doses (1000, 2000, 3000, 4000 and 5000 IU/kg) in a large number of females (208 animals) from two Nile tilapia lines. The results indicated that hCG doses between 1000 and 5000 IU/kg could be used to induce final oocyte maturation in Nile tilapia with collection of stripped oocytes. This is the first study to report differential reproductive responses to hormonal treatment between tilapia lines: line 1 was more efficient at producing eggs and post‐hatching larvae after hCG induction than line 2. In conclusion, we demonstrated that the hCG protocol may be applied on a large scale to induce final oocyte maturation in Nile tilapia. The development of a protocol for in vitro fertilization in Nile tilapia may aid in breeding programmes and biotechnological assays for the development of genetically modified lines of Nile tilapia.  相似文献   

The in vitro response of field strains of sheep blowflies Lucilia sericata and L. cuprina (Calliphoridae) in New Zealand to dicyclanil and triflumuron     

T S Waghorn  C H McKay  A CG Heath 《New Zealand veterinary journal》2013,61(5):274-280

AIM: To evaluate the in vitro efficacy of triflumuron and dicyclanil against field strains of Lucilia sericata and L. cuprina in New Zealand to establish whether anecdotal reports of declining protection periods afforded by dips containing these active ingredients had validity.

METHODS: Strains of field-derived blowflies (Lucilia cuprina and L. sericata) were obtained from adult flies from flytraps or larvae from sheep with flystrike submitted from seven regions of the North and two regions of the South Islands of New Zealand. A total of 27 strains of L. sericata and 19 of L. cuprina were established in culture and first instar larvae obtained were exposed in vitro to dilution series of technical-grade dicyclanil (a pyrimidine carbonitrile) and triflumuron (a benzoyl urea). Concentrations lethal to 50% (LC₅₀) and 95% (LC₉₅) of each strain were calculated and tested by probit analysis, with the ratio of LC₅₀ of each strain divided by LC₅₀ of the most susceptible strain (resistance factor) derived in order to facilitate between-strain comparisons of susceptibility.

RESULTS: There was considerable variation between strains of L. sericata larvae in their susceptibility to triflumuron, with those least susceptible originating from the Waikato region. Strains from both Tararua and Manawatu regions were most susceptible and East Coast strains intermediate. All strains of the species tested showed a narrow band of susceptibility to dicyclanil with no regional trends apparent.

CONCLUSIONS: Representative field-strains of sheep blowflies exhibited a range of susceptibilities to both triflumuron and dicyclanil, suggestive of both genetic heterogeneity among fly populations and the spectrum of dip use in their source areas. This means there should be concerns for the long-term benefits of benzoyl urea insecticides for sheep farmers in New Zealand, but not yet for dicyclanil-based formulations.

CLINICAL RELEVANCE: Flystrike is a debilitating and occasionally lethal disease in sheep such that efficacious sheep dips have prophylactic value in reducing the prevalence of the condition.  相似文献   

(Highly pathogenic) avian influenza as a zoonotic agent     

Donata Kalthoff  Anja Globig  Martin Beer 《Veterinary microbiology》2010,140(3-4):237-245

Zoonotic agents challenging the world every year afresh are influenza A viruses. In the past, human pandemics caused by influenza A viruses had been occurring periodically. Wild aquatic birds are carriers of the full variety of influenza virus A subtypes, and thus, most probably constitute the natural reservoir of all influenza A viruses. Whereas avian influenza viruses in their natural avian reservoir are generally of low pathogenicity (LPAIV), some have gained virulence by mutation after transmission and adaptation to susceptible gallinaceous poultry. Those so-called highly pathogenic avian influenza viruses (HPAIV) then cause mass die-offs in susceptible birds and lead to tremendous economical losses when poultry is affected. Besides a number of avian influenza virus subtypes that have sporadically infected mammals, the HPAIV H5N1 Asia shows strong zoonotic characteristics and it was transmitted from birds to different mammalian species including humans. Theoretically, pandemic viruses might derive directly from avian influenza viruses or arise after genetic reassortment between viruses of avian and mammalian origin. So far, HPAIV H5N1 already meets two conditions for a pandemic virus: as a new subtype it has been hitherto unseen in the human population and it has infected at least 438 people, and caused severe illness and high lethality in 262 humans to date (August 2009). The acquisition of efficient human-to-human transmission would complete the emergence of a new pandemic virus. Therefore, fighting H5N1 at its source is the prerequisite to reduce pandemic risks posed by this virus. Other influenza viruses regarded as pandemic candidates derive from subtypes H2, H7, and H9 all of which have infected humans in the past. Here, we will give a comprehensive overview on avian influenza viruses in concern to their zoonotic potential.  相似文献   

Structure–activity relationship studies of the phytotoxic properties of the diterpenic moiety of breviones          下载免费PDF全文

Ceferino Carrera  Nuria Chinchilla  Frank R Fronczek  Juan CG Galindo  Francisco A Macías 《Pest management science》2015,71(5):701-711

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