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51.
Hepatopancreatic parvovirus (HPV) can cause stunted growth and death in penaeid shrimp including Penaeus monodon. We used PCR primers and a commercial DNA probe designed from HPV of Penaeus chinensis (HPVchin) to examine HPV-infected Thai P. monodon (HPVmon). We found that the PCR primers produced a 732 bp DNA amplicon rather than the 350 bp amplicon obtained with HPVchin template and that the DNA probe gave weak to variable in situ DNA hybridization results. In addition, hybridization to PCR products from HPVmon was weak compared with hybridization with PCR products from HPVchin. By contrast, the 732 bp amplicon hybridized strongly with HPVmon-infected cells by in situ hybridization but not with uninfected shrimp tissue or other shrimp viruses, thus confirming its origin from HPVmon. Cloning, sequencing and analysis of the 732 bp amplicon showed that 696 bp (excluding the primer sequences) contained 47% GC content and had only 78% homology to 701 aligned bases from a 3350 bp DNA fragment of HPVchin from GenBank. These results explain why the reagents based on HPVchin gave a different PCR product and weak hybridization results with HPVmon, and they show that multiple primers or degenerate primers may be necessary for general detection of HPV varieties. Together with previously published information on the estimated total genome sizes for HPVchin (approximately 4 kb) and HPVmon (approximately 6 kb), these data support the contention that HPVchin and HPVmon are different varieties or species, in spite of their similar histopathology.  相似文献   
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Two new genera and three new species of paramphistomoid digeneans are described in the family Cladorchiidae Fischoeder, 1901 from doradid, heptapterid, pimelodid and pseudopimelodid fishes in the Amazon River in Peru. Goeldamphistomum amazonum n. g., n. sp. (type-species) from Goeldiella eques (Müller & Troschel) (type-host) and Tenellus trimaculatus (Boulenger), and Goeldamphistomum peruanum n. g., n. sp. from Duopalatinus peruanus Eigenmann & Allen (type-host), Calophysus macropterus (Lichtenstein) and Microglanis sp. are placed in the Dadayiinae Fukui, 1929. Both species have an accessory acetabular sucker, which distinguishes the genus from all taxa previously reported from South American freshwater fishes. They differ from each other primarily in that G. amazonum has a prebifurcal genital pore and oblique, separated testes, the levels of which rarely overlap longitudinally, whereas G. peruanum has a postbifurcal genital pore and testes directly to obliquely tandem. Iquitostrema papillatum n. g., n. sp. (Kalitrematinae Travassos, 1933) from the intestine of Hassar orestis (Steindachner) differs from other members of the subfamily in the combination of a massive acetabulum with a papillate luminal surface and symmetrical testes which overlie the caeca close to the caecal arch. These are the first records of paramphistomes from the five host species studied here.  相似文献   
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Seasonal influenza causes significant morbidity and mortality and has a substantial economic impact on the healthcare system. The main objective of this study was to compare the cost per patient for a rapid commercial PCR assay (Xpert® Flu) with an in-house real-time PCR test for detecting influenza virus. Community patients with influenza like-illness attending the Emergency Department (ED) as well as hospitalized patients in the Hospital Clínic of Barcelona were included. Costs were evaluated from the perspective of the hospital considering the use of resources directly related to influenza testing and treatment. For the purpose of this study, 366 and 691 patients were tested in 2013 and 2014, respectively. The Xpert® Flu test reduced the mean waiting time for patients in the ED by 9.1 hours and decreased the mean isolation time of hospitalized patients by 23.7 hours. This was associated with a 103€ (or about $113) reduction in the cost per patient tested in the ED and 64€ ($70) per hospitalized patient. Sensitivity analyses showed that Xpert® Flu is likely to be cost-saving in hospitals with different contexts and prices.  相似文献   
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We report on the first, to our knowledge, successful detection of a fluorescent unnatural amino acid (fUAA), Lys(BODIPYFL), incorporated into a membrane protein (the muscle nicotinic acetylcholine receptor, nAChR) in a living cell. Xenopus oocytes were injected with a frameshift-suppressor tRNA, amino-acylated with Lys(BODIPYFL) and nAChR (α/β19′GGGU/γ/δ) mRNAs. We measured fluorescence from oocytes expressing nAChR β19′Lys(BODIPYFL), using time-resolved total internal reflection fluorescence microscopy. Under conditions of relatively low receptor density (<0.1 receptors/μm2), we observed puncta with diffraction-limited profiles that were consistent with the point-spread function of our microscope. Furthermore, diffraction-limited puncta displayed step decreases in fluorescence intensity, consistent with single-molecule photobleaching. The puncta densities agreed with macroscopic ACh-induced current densities, showing that the fUAA was incorporated, and that receptors were functional. Dose-response relations for the nAChR β19′Lys(BODIPYFL) receptors were similar to those for wild-type receptors. We also studied nAChR β19′Lys(BODIPYFL) receptors labeled with α-bungarotoxin monoconjugated with Alexa488 (αBtxAlexa488). The nAChR has two αBtx binding sites, and puncta containing the Lys(BODIPYFL) labeled with αBtxAlexa488 yielded the expected three discrete photobleaching steps. We also performed positive control experiments with a nAChR containing enhanced green fluorescent protein in the γ-subunit M3-M4 loop, which confirmed our nAChR β19′Lys(BODIPYFL) measurements. Thus, we report on the cell-based single-molecule detection of nAChR β19′Lys(BODIPYFL).  相似文献   
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International Microbiology - Gallic acid is a powerful antioxidant with multiple therapeutic applications, usually obtained from the acidic hydrolysis of tannins produced by many plants. As this...  相似文献   
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Progress and challenges for abiotic stress proteomics of crop plants   总被引:1,自引:0,他引:1  
Plants are continually challenged to recognize and respond to adverse changes in their environment to avoid detrimental effects on growth and development. Understanding the mechanisms that crop plants employ to resist and tolerate abiotic stress is of considerable interest for designing agriculture breeding strategies to ensure sustainable productivity. The application of proteomics technologies to advance our knowledge in crop plant abiotic stress tolerance has increased dramatically in the past few years as evidenced by the large amount of publications in this area. This is attributed to advances in various technology platforms associated with MS‐based techniques as well as the accessibility of proteomics units to a wider plant research community. This review summarizes the work which has been reported for major crop plants and evaluates the findings in context of the approaches that are widely employed with the aim to encourage broadening the strategies used to increase coverage of the proteome  相似文献   
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