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951.
Esteban Soto Matt Griffin Maziel Arauz Andres Riofrio Alexis Martinez Maria Eugenia Cabrejos 《Journal of aquatic animal health》2013,25(2):81-90
Abstract Edwardsiella ictaluri was consistently isolated from the spleens, livers, and head kidneys of diseased Nile tilapia Oreochromis niloticus from a farm experiencing mortality events in several culture ponds. We describe the first published outbreak of E. ictaluri–induced edwardsiellosis in Nile tilapia. Pure cultures of the isolated bacteria were characterized both biochemically and molecularly. Biochemical analysis was performed using the API-20E and RapID One systems, and antimicrobial susceptibility was determined by the broth microdilution method. Molecular analysis involved sequencing of the 16S rRNA gene, species-specific real-time polymerase chain reaction (PCR), and PCR-mediated genomic fingerprinting (rep-PCR). Pairwise sequence analysis of the 16S rRNA gene identified the case isolates to be a 100% match to E. ictaluri cultured from channel catfish in the southeastern United States. However, rep-PCR analysis identified the case isolates to be genetically different from representative strains isolated from disease outbreaks in cultured channel catfish in Mississippi. Infectivity challenges (intraperitoneal injection and immersion) demonstrated that a representative E. ictaluri strain isolated from tilapia was pathogenic to naïve tilapia, reproducing clinical signs and mortality, thereby establishing Koch's postulates. Received August 30, 2011; accepted January 30, 2012 相似文献
952.
Matt J. Griffin Michael J. Mauel Terrence E. Greenway Lester H. Khoo David J. Wise 《Journal of aquatic animal health》2013,25(4):178-188
Abstract A quantitative polymerase chain reaction (qPCR) assay was developed for the detection and quantification of Edwardsiella ictaluri in channel catfish Ictalurus punctatus pond water using modifications to a published E. ictaluri–specific qPCR assay and previously established protocols for the molecular detection of myxozoan parasites in catfish ponds. Genomic DNA equivalents indicative of the number of bacteria in a sample were determined and standard curves correlating to bacterial numbers were established. The assay was found to be highly repeatable and reproducible, with a linear dynamic range of five orders of magnitude. There was no interference of the assay from the presence of large quantities of nontarget DNA. Known quantities of bacteria were added to sample volumes of 40 or 500 mL of pond water collected from several different ponds. The minimum level of detection was approximately 100 cell equivalents (CE) in 40 (2.5 CE/mL) or 500 mL of pond water (0.2 CE/mL). Sample volumes of 40 mL yielded the most consistent results, which were not significantly different from those obtained from broth culture alone. Cell equivalents determined by qPCR in 40-mL pond water samples spiked with known quantities of bacteria were within one order of magnitude of the actual number of cells added. Repetitive element-based polymerase chain reaction analysis of archived isolates demonstrated the genetic homogeneity of E. ictaluri, and consistent amplification of these isolates by qPCR analysis demonstrated the stability of the PCR target. The assay described here provides a reliable method for the detection and quantification of E. ictaluri in pond water and will be an invaluable tool in epidemiological studies. Additionally, the assay provides a way to evaluate the effects that vaccination, antibiotic treatments, and restricted feeding practices have on E. ictaluri populations during an outbreak. Information obtained with these tools will aid in optimizing disease management practices designed to maximize productivity while minimizing losses. Received October 20, 2010; accepted June 13, 2011 相似文献
953.
Bernardo Júnior Luiz Antonio Yanes Von Pinho Renzo Garcia da Silva Carlos Pereira Vieira Júnior Indalécio Cunha de Oliveira Luciano Antonio Silva Eric Vinicius Vieira 《Euphytica》2021,217(8):1-1
Euphytica - With globalization and easy access to information, a consumer market that is more conscious and focused on the search for superior quality coffees appears. 相似文献
954.
Dopamine: release from the brain in vivo by amantadine 总被引:4,自引:0,他引:4
After dopamine stores in the caudate nucleus of cats were labeled with [(3)H]dopamine, the ventricular system was perfused with artificial cerebrospinal fluid. The addition of amantadine to the perfusing fluid caused a doserelated increase in the concentrations of [(3)H]dopamine appearing in the perfusion effluent. Subthreshold concentrations of amantadine also enhanced the efflux of [(3)H]dopamine induced by electrical stimulation of the caudate nucleus. 相似文献
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Nene V Wortman JR Lawson D Haas B Kodira C Tu ZJ Loftus B Xi Z Megy K Grabherr M Ren Q Zdobnov EM Lobo NF Campbell KS Brown SE Bonaldo MF Zhu J Sinkins SP Hogenkamp DG Amedeo P Arensburger P Atkinson PW Bidwell S Biedler J Birney E Bruggner RV Costas J Coy MR Crabtree J Crawford M Debruyn B Decaprio D Eiglmeier K Eisenstadt E El-Dorry H Gelbart WM Gomes SL Hammond M Hannick LI Hogan JR Holmes MH Jaffe D Johnston JS Kennedy RC Koo H Kravitz S Kriventseva EV Kulp D Labutti K Lee E Li S Lovin DD 《Science (New York, N.Y.)》2007,316(5832):1718-1723
We present a draft sequence of the genome of Aedes aegypti, the primary vector for yellow fever and dengue fever, which at approximately 1376 million base pairs is about 5 times the size of the genome of the malaria vector Anopheles gambiae. Nearly 50% of the Ae. aegypti genome consists of transposable elements. These contribute to a factor of approximately 4 to 6 increase in average gene length and in sizes of intergenic regions relative to An. gambiae and Drosophila melanogaster. Nonetheless, chromosomal synteny is generally maintained among all three insects, although conservation of orthologous gene order is higher (by a factor of approximately 2) between the mosquito species than between either of them and the fruit fly. An increase in genes encoding odorant binding, cytochrome P450, and cuticle domains relative to An. gambiae suggests that members of these protein families underpin some of the biological differences between the two mosquito species. 相似文献
958.
OBJECTIVE: A number of individual risk factors for childhood obesity have been identified, but only some of these are amenable to prevention. To assess the amount of cases in a general population attributable to these risk factors, adjusted population-attributable fractions were estimated. DESIGN: Cross-sectional study. SETTING: Obligatory school entry examination in 2001/2002 in six Bavarian communities (Germany). SUBJECTS: 5472 children at age 5-6 years. MEASURES: Anthropometric measures were ascertained by public health nurses, and measures concerning sociodemographics, lifestyle and child behaviour such as child's daily meal frequency were obtained with self-administered parental questionnaires. Obesity was defined according to sex- and age-specific body mass index cut-off points proposed by the International Obesity Task Force. Adjusted population-attributable fractions were calculated based on logistic regression. RESULTS: A combination of the risk factors low meal frequency, decreased physical activity, watching television >1 h day- 1, formula feeding and smoking in pregnancy accounted for 48.2% of obese children. This combination yielded a maximal achievable prevalence reduction of 1.5% for obesity (3.2% observed prevalence). CONCLUSIONS: A modification of five known risk factors for childhood overweight and obesity could reasonably lower obesity prevalences at school entry. These risk factors should be particularly considered in decision making on preventive measures. 相似文献