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101.
Amod D. Kulkarni Viswanath Kiron Jan H. W. M. Rombout Monica F. Brinchmann Jorge M. O. Fernandes Naduvilamuriparampu S. Sudheer Bright I. S. Singh 《Proteomics》2014,14(13-14):1660-1673
White spot syndrome virus (WSSV) is a pathogen that causes considerable mortality of the farmed shrimp, Penaeus monodon. Candidate ‘vaccines’, WSSV envelope protein VP28 and formalin‐inactivated WSSV, can provide short‐lived protection against the virus. In this study, P. monodon was orally intubated with the aforementioned vaccine candidates, and protein expression in the gut of immunised shrimps was profiled. The alterations in protein profiles in shrimps infected orally with live‐WSSV were also examined. Seventeen of the identified proteins in the vaccine and WSSV‐intubated shrimps varied significantly compared to those in the control shrimps. These proteins, classified under exoskeletal, cytoskeletal, immune‐related, intracellular organelle part, intracellular calcium‐binding or energy metabolism, are thought to directly or indirectly affect shrimp's immunity. The changes in the expression levels of crustacyanin, serine proteases, myosin light chain, and ER protein 57 observed in orally vaccinated shrimp may probably be linked to immunoprotective responses. On the other hand, altered expression of proteins linked to exoskeleton, calcium regulation and energy metabolism in WSSV‐intubated shrimps is likely to symbolise disturbances in calcium homeostasis and energy metabolism. 相似文献
102.
Ripening in papaya fruit is altered by ACC oxidase cosuppression 总被引:2,自引:0,他引:2
López-Gómez R Cabrera-Ponce JL Saucedo-Arias LJ Carreto-Montoya L Villanueva-Arce R Díaz-Perez JC Gómez-Lim MA Herrera-Estrella L 《Transgenic research》2009,18(1):89-97
Papaya (Carica papaya) is a very important crop in many tropical countries but it is highly susceptible to parasitic diseases, physiological disorders,
mechanical damage and fruit overripening. Here we report a study on ACC oxidase cosuppression and its effects on papaya fruit
ripening. Papaya ACC oxidase was isolated using PCR and embriogenic cells transformed by biolistic using the CaMV 35S promoter
to drive the expression of the PCR fragment in sense orientation. Fifty transgenic lines were recovered and 20 of those were
grown under field conditions. Southern analysis showed incorporation of the transgene in different copy numbers in the papaya
genome. Fruits were evaluated in terms of texture (firmness), colour development, respiration and ethylene production. A sharp
reduction in ethylene and CO2 production was detected, whereas softening and colour development of the peel were also altered.
Overall, transgenic fruits showed a delay in ripening rate. A reduction in mRNA level for ACC oxidase in transgenic fruit
was clearly detectable by northern blot. More studies are necessary before this technology can be used to extend the shelf
life of papaya fruit. 相似文献
103.
Caleja C de Toro M Gon?alves A Themudo P Vieira-Pinto M Monteiro D Rodrigues J Sáenz Y Carvalho C Igrejas G Torres C Poeta P 《International microbiology》2011,14(1):19-24
The antibiotic resistance phenotype and genotype and the integron type were characterized in 58 Salmonella enterica isolates recovered from Bísaro pigs and wild boars (20 S. Typhimurium, 17 S. Rissen, 14 S. Enteritidis and 7 S. Havana). Most S. Typhimurium isolates (15/20 of Bísaro pigs and wild boars) showed ampicillin, chloramphenicol, streptomycin, tetracycline, sulfonamide, and amoxicillin-clavulanic acid resistances. Of the 17 S. Rissen isolates of both origins, 13 were resistant to ampicillin, tetracycline and trimethoprim-sulfamethoxazole. Among the S. Enteritidis isolates of Bísaro pigs, eight were nalidixic acid-resistant and three were sulfonamide-resistant. The tet(A) or tet(G) genes were detected in most tetracycline-resistant isolates. The intI1 gene was identified in 72.5% of S. enterica isolates in which the conserved region 3' of class 1 integrons (qacEΔ1+sul1) was also amplified, whereas none had the intI2 gene. The dfrA12+orfF+aadA2 gene cassette arrangement was found in the variable region of class 1 integrons in 14 S. Rissen isolates. Fifteen S. Typhimurium isolates had two integrons with variable regions of 1000 and 1200 bp that harbored the aadA2 and blaPSE-1 gene cassettes, respectively. In these isolates the floR and tet(G) genes were also amplified, indicative of the genomic island 1 (SGI1). Salmonella Typhimurium and S. Rissen of animal origin frequently show a multi-antimicrobial resistant phenotype, which may have implications in public health. 相似文献
104.
105.
The aim of this work was to evaluate a fungal DNA extraction procedure with the lowest inputs in terms of time as well as of expensive and toxic chemicals, but able to consistently produce genomic DNA of good quality for PCR purposes. Two types of fungal biological material were tested ‐ mycelium and conidia ‐ combined with two protocols for DNA extraction using Sodium Dodecyl Sulphate (SDS) and Cetyl Trimethyl Ammonium Bromide as extraction buffers and glass beads for mechanical disruption of cell walls. Our results showed that conidia and SDS buffer was the combination that lead to the best DNA quality and yield, with the lowest variation between samples. This study clearly demonstrates that it is possible to obtain high yield and pure DNA from pigmented conidia without the use of strong cell disrupting procedures and of toxic reagents.
Significance and Impact of the Study
There are numerous methods for DNA extraction from fungi. Some rely on expensive commercial kits and/or equipments, unavailable for many laboratories, or make use of toxic chemicals such as chloroform, phenol and mercaptoethanol. This study clearly demonstrates that it is possible to obtain high yields of pure DNA from pigmented conidia without the use of strong and expensive cell disrupting procedures and of toxic reagents. The method herein described is simultaneously inexpensive and adequate to DNA extraction from several different types of fungi. 相似文献106.
Nicolás Fuenzalida‐Uribe Rodrigo C. Meza Hernán A. Hoffmann Rodrigo Varas Jorge M. Campusano 《Journal of neurochemistry》2013,125(2):281-290
Biogenic amines (BAs) play a central role in the generation of complex behaviors in vertebrates and invertebrates, including the fly Drosophila melanogaster. The comparative advantages of Drosophila as a genetic model to study the contribution of BAs to behaviors stumble upon the difficulty to access the fly brain to ask relevant physiological questions. For instance, it is not known whether the activation of nicotinic acetylcholine receptors (nAChRs) induces the release of BAs in fly brain, a phenomenon associated to several behaviors in vertebrates. Here, we describe a new preparation to study the efflux of BAs in the adult fly brain by in vitro chronoamperometry. Using this preparation we show that nAChR agonists including nicotine induce a fast, transient, dose‐dependent efflux of endogenous BAs, an effect mediated by α‐bungarotoxin‐sensitive nAChRs. By using different genetic tools we demonstrate that the BA whose efflux is induced by nAChR activation is octopamine (Oct). Furthermore, we show that the impairment of a mechanically induced startle response after nicotine exposure is not observed in flies deficient in Oct transmission. Thus, our data show that the efflux of BAs in Drosophila brain is increased by nAChR activation as in vertebrates, and that then AChR‐induced Oct release could have implications in a nicotine‐induced behavioral response. 相似文献
107.
Albert K. Hoang Duc Marc Modat Kelvin K. Leung M. Jorge Cardoso Josephine Barnes Timor Kadir Sébastien Ourselin for the Alzheimer’s Disease Neuroimaging Initiative 《PloS one》2013,8(8)
Multi-atlas segmentation has been widely used to segment various anatomical structures. The success of this technique partly relies on the selection of atlases that are best mapped to a new target image after registration. Recently, manifold learning has been proposed as a method for atlas selection. Each manifold learning technique seeks to optimize a unique objective function. Therefore, different techniques produce different embeddings even when applied to the same data set. Previous studies used a single technique in their method and gave no reason for the choice of the manifold learning technique employed nor the theoretical grounds for the choice of the manifold parameters. In this study, we compare side-by-side the results given by 3 manifold learning techniques (Isomap, Laplacian Eigenmaps and Locally Linear Embedding) on the same data set. We assess the ability of those 3 different techniques to select the best atlases to combine in the framework of multi-atlas segmentation. First, a leave-one-out experiment is used to optimize our method on a set of 110 manually segmented atlases of hippocampi and find the manifold learning technique and associated manifold parameters that give the best segmentation accuracy. Then, the optimal parameters are used to automatically segment 30 subjects from the Alzheimer’s Disease Neuroimaging Initiative (ADNI). For our dataset, the selection of atlases with Locally Linear Embedding gives the best results. Our findings show that selection of atlases with manifold learning leads to segmentation accuracy close to or significantly higher than the state-of-the-art method and that accuracy can be increased by fine tuning the manifold learning process. 相似文献
108.
109.
Severo Juliana Soares Morais Jennifer Beatriz Silva Beserra Jessica Batista dos Santos Loanne Rocha de Sousa Melo Stéfany Rodrigues de Sousa Gustavo Santos de Matos Neto Emídio Marques Henriques Gilberto Simeone do Nascimento Marreiro Dilina 《Biological trace element research》2020,193(1):81-88
Biological Trace Element Research - Excessive adipose tissue promotes the manifestation of endocrine disorders such as reduction of the secretion of zinc-α2-glycoprotein (ZAG), an adipokine... 相似文献
110.
Pineda Alfonso Iatskiu Patrícia Jati Susicley Paula Aline C. M. Zanco Bárbara F. Bonecker Claudia C. Moresco Geovani A. Ortega Laura A. Souza Yasmin R. Rodrigues Luzia C. 《Hydrobiologia》2020,847(18):3857-3875
Hydrobiologia - We analyzed the effect of damming on the temporal patterns of the composition and richness of phytoplankton Reynolds functional groups (RFG) from a subtropical floodplain, together... 相似文献