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https://www.readbyqxmd.com/read/28105747/virulence-and-genotypes-of-white-spot-syndrome-virus-infecting-pacific-white-shrimp-litopenaeus-vannamei-in-north-western-mexico
#1
J Ramos-Paredes, J M Grijalva-Chon, J C Ibarra-Gámez
White spot syndrome virus (WSSV) has caused substantial global economic impact on aquaculture, and it has been determined that strains can vary in virulence. In this study, the effect of viral load was evaluated by infecting Litopenaeus vannamei with 10-fold serial dilution of tissue infected with strain WSSV Mx-H, and the virulence of four WSSV strains from north-western Mexico was assessed along with their variable number of tandem repeat (VNTR) genotypes in ORF75, ORF94 and ORF125. The LD50 of the Mx-H strain was a dilution dose of 10(-7...
January 20, 2017: Journal of Fish Diseases
https://www.readbyqxmd.com/read/28102038/edta-is-superior-to-dtt-treatment-for-overcoming-the-prozone-effect-in-hla-antibody-testing
#2
J Wang, J R Meade, N K Brown, J G Weidner, S R Marino
A limitation of solid-phase human leukocyte antigen (HLA) antibody assays is the falsely low/negative result of samples with high-titer antibodies, a phenomenon known as the prozone effect. Here we compared the efficacy of ethylenediaminetetraacetic acid (EDTA) and dithiothreitol (DTT) treatment of serum samples in overcoming the prozone effect. A total of 21 serum samples were treated with either EDTA or DTT before HLA single antigen bead assay. The efficacy of prozone effect reversal, compared with untreated samples, was examined on fourfold, serially diluted samples, from neat to 1:256, using PBS as diluent...
February 2017: HLA
https://www.readbyqxmd.com/read/28101272/isolation-and-characterization-of-agrobacterium-strains-from-soil-a-laboratory-capstone-experience
#3
Kim R Finer, Lee Fox, John J Finer
In this investigation, the students' goal was to isolate and characterize Agrobacterium strains from soil. Following selection and enrichment on 1A-t medium, putative Agrobacterium isolates were characterized by Gram stain reaction and biochemical tests. Isolates were further evaluated using polymerase chain reaction (PCR) with different primer sets designed to amplify specific regions of bacterial deoxyribonucleic acid (DNA). Primer sets included AGRH to identify isolates that were members of the Rhizobiaceae, BIOVAR1 primers to identify members of Agrobacterium biovar group I, and a third set, VIRG, to determine presence of virG (only present in pathogenic Agrobacterium strains)...
December 2016: Journal of Microbiology & Biology Education: JMBE
https://www.readbyqxmd.com/read/28099189/productive-infection-of-human-neural-progenitor-cells-by-r5-tropic-hiv-1-opiate-co-exposure-heightens-infectivity-and-functional-vulnerability
#4
Joyce M Balinang, Ruturaj R Masvekar, Kurt F Hauser, Pamela E Knapp
OBJECTIVE: Human immunodeficiency virus type-1 (HIV-1) causes a spectrum of CNS complications; many are worsened by opiate co-exposure. Human neural progenitor cells (hNPCs) give rise to all CNS neurons and macroglia. We tested the hypothesis that hNPC maturation and fate are altered by HIV and opiates, contributing to HIV-1-related neuropathology. Since reports that hNPCs are infectable remain controversial, we rigorously examined hNPC infection and ability to propagate infection, and determined whether HIV effects on hNPC function required infection...
January 17, 2017: AIDS
https://www.readbyqxmd.com/read/28092732/enhancement-of-lipid-productivity-by-adopting-multi-stage-continuous-cultivation-strategy-in-nannochloropsis-gaditana
#5
Min-Gyu Sung, Bongsoo Lee, Chul Woong Kim, Kibok Nam, Yong Keun Chang
In the present study, a novel process-based cultivation system was designed to improve lipid productivity of Nannochloropsis gaditana, an oleaginous microalga that has high potential for biofuel production. Specifically, four flat-panel photobioreactors were connected in series, and this system was subjected to continuous chemostat cultivation by feeding fresh medium to the first reactor at dilution rates of 0.028 and 0.056day(-1), which were determined based on Monod kinetics. The results show that the serially connected photobioreactor system achieved 20...
December 30, 2016: Bioresource Technology
https://www.readbyqxmd.com/read/28089353/cerebrospinal-fluid-mitochondrial-dna-in-the-alzheimer-s-disease-continuum
#6
Laura Cervera-Carles, Daniel Alcolea, Ainara Estanga, Mirian Ecay-Torres, Andrea Izagirre, Montserrat Clerigué, Maite García-Sebastián, Jorge Villanúa, Clàudia Escalas, Rafael Blesa, Pablo Martínez-Lage, Alberto Lleó, Juan Fortea, Jordi Clarimón
Low levels of cell-free mitochondrial DNA (mtDNA) in the cerebrospinal fluid (CSF) of Alzheimer's disease (AD) patients have been identified and proposed as a novel biomarker for the disease. The lack of validation studies of previous results prompted us to replicate this finding in a comprehensive series of patients and controls. We applied droplet digital polymerase chain reaction in CSF specimens from 124 patients representing the AD spectrum and 140 neurologically healthy controls. The following preanalytical and analytical parameters were evaluated: the effect of freeze-thaw cycles on mtDNA, the linearity of mtDNA load across serial dilutions, and the mtDNA levels in the diagnostic groups...
December 22, 2016: Neurobiology of Aging
https://www.readbyqxmd.com/read/28088715/micropollutant-induced-tolerance-of-in-situ-periphyton-establishing-causality-in-wastewater-impacted-streams
#7
Ahmed Tlili, Juliane Hollender, Cornelia Kienle, Renata Behra
The overarching aim of this field study was to examine causal links between in-situ exposure to complex mixtures of micropollutants from wastewater treatment plants and effects on freshwater microbial communities in the receiving streams. To reach this goal, we assessed the toxicity of serial dilutions of micropollutant mixtures, extracted from deployed passive samplers at the discharge sites of four Swiss wastewater treatment plants, to in situ periphyton from upstream and downstream of the effluents. On the one hand, comparison of the sensitivities of upstream and downstream periphyton to the micropollutant mixtures indicated that algal and bacterial communities composing the periphyton displayed higher tolerance towards these micropollutants downstream than upstream...
January 7, 2017: Water Research
https://www.readbyqxmd.com/read/28077644/ultrasensitive-hiv-1-p24-detects-single-infected-cells-and-differences-in-reservoir-induction-by-latency-reversal-agents
#8
Caroline Pereira Bittencourt Passaes, Timothée Bruel, Jérémie Decalf, Annie David, Mathieu Angin, Valerie Monceaux, Michaela Muller-Trutwin, Nicolas Noel, Katia Bourdic, Olivier Lambotte, Matthew L Albert, Darragh Duffy, Olivier Schwartz, Asier Sáez-Cirión
: The existence of HIV reservoirs in infected individuals under cART represents a major obstacle towards cure. Viral reservoirs are assessed by quantification of HIV nucleic acids, which does not discriminate between infectious and defective viruses, or by viral outgrowth assays, which requires large number of cells and long-term cultures. Here, we used an ultrasensitive p24 digital assay, which we report to be 1000 fold more sensitive than classical ELISA in the quantification of HIV-1 Gag p24 production in HIV-infected individuals samples...
January 11, 2017: Journal of Virology
https://www.readbyqxmd.com/read/28077194/the-response-of-weaned-piglets-to-dietary-valine-and-leucine
#9
F Meyer, C Jansen van Rensburg, R M Gous
Valine (Val) is considered to be the fifth-limiting amino acid in a maize-soyabean meal diet for pigs. Excess leucine (Leu) levels often occur in commercial diets, which may attenuate the effect of Val deficiency because of an increased oxidation of Val. The objective of the present experiment was to determine the effect of increasing concentrations of Leu on the response of young piglets to dietary Val. In all, 75 Large White×Landrace entire male pigs, 44 days of age and with a mean starting weight of 13...
January 12, 2017: Animal: An International Journal of Animal Bioscience
https://www.readbyqxmd.com/read/28070163/development-of-reverse-transcription-loop-mediated-isothermal-amplification-for-simple-and-rapid-detection-of-promyelocytic-leukemia-retinoic-acid-receptor-%C3%AE-mrna
#10
Yuki Hashimoto, Yuki Hatayama, Nao Kojima, Shota Morishita, Satoko Matsumoto, Yuzuru Hosoda, Ayako Hara, Toru Motokura
BACKGROUND: Acute promyelocytic leukemia (APL) is a disease characterized by expression of Promyelocytic Leukemia-Retinoic Acid Receptor α (PML-RARα) chimeric mRNA. Although APL is curable, early death due to hemorrhage is a major problem. Here, we report the development of a simple and rapid diagnostic method for APL based on reverse transcription loop-mediated isothermal amplification (RT-LAMP). METHODS: An RT-LAMP primer set was designed to detect three types of PML-RARα mRNA in a single reaction...
December 2016: Yonago Acta Medica
https://www.readbyqxmd.com/read/28064422/improved-detection-of-mineral-oil-toxicity-using-an-extended-mouse-embryo-assay
#11
Alessandra J Ainsworth, Jolene R Fredrickson, Dean E Morbeck
PURPOSE: Successful in vitro fertilization (IVF) relies on sound laboratory methods and culture conditions which depend on sensitive quality control (QC) testing. This study aimed to improve the sensitivity of mouse embryo assays (MEA) for detection of mineral oil toxicity. METHODS: Five experiments were conducted to study modifications of the standard mouse embryo assay (MEA) in order to improve sensitivity using clinical grade mineral oil with known peroxide concentrations...
January 7, 2017: Journal of Assisted Reproduction and Genetics
https://www.readbyqxmd.com/read/28063652/molecular-and-carbon-isotopic-characterization-of-an-anaerobic-stable-enrichment-culture-containing-dehalobacterium-sp-during-dichloromethane-fermentation
#12
Alba Trueba-Santiso, Eloi Parladé, Mònica Rosell, Marc Lliros, Siti Hatijah Mortan, Maira Martínez-Alonso, Nuria Gaju, Lucía Martín-González, Teresa Vicent, Ernest Marco-Urrea
: Biodegradation of dichloromethane (DCM) under reducing conditions is of major concern due to its widespread detection in contaminated groundwaters. Here, we report an anaerobic enrichment culture derived from a membrane bioreactor operating in an industrial wastewater treatment plant, capable of fermenting DCM and the brominated analogue dibromomethane (DBM). Comparative analysis of bacterial 16S rDNA-DGGE profiles from fresh liquid medium inoculated with single colonies picked from serial dilution-to-extinction agar vials showed that cultures degrading DCM contained a predominant band belonging to Dehalobacterium, however this band was absent in cultures unable to degrade DCM...
January 4, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28058577/development-of-an-indirect-dot-ppa-elisa-using-glutamate-dehydrogenase-as-a-diagnostic-antigen-for-the-rapid-and-specific-detection-of-streptococcus-suis-and-its-application-to-clinical-specimens
#13
Xiao-Jing Xia, Lei Wang, Zhi-Qiang Shen, Wanhai Qin, Jianhe Hu, Shi-Jin Jiang, Shu-Guang Li
Streptococcus suis is an important zoonotic pathogen causing infections in pigs and humans. Bacterial surface-related proteins are often explored as potential vaccine candidates and diagnostic antigens. In the present study, glutamate dehydrogenase, a highly conserved immunogenic extracellular protein, was used to establish a dot horseradish peroxidase enzyme-linked staphylococcal protein A immunosorbent assay (Dot-PPA-ELISA) for diagnosis of S. suis infection. The antigen-antibody reaction was optimised through checkerboard titration involving serial dilutions, followed by selective blocking tests and evaluations of cross-reaction, repeatability, and stability...
January 5, 2017: Antonie Van Leeuwenhoek
https://www.readbyqxmd.com/read/28058525/the-visual-assessment-of-broth-cultures-for-tissue-bank-samples
#14
Kerry Varettas
The bioburden screening process of allograft musculoskeletal tissue samples received at the South Eastern Area Laboratory Services includes the routine use of solid agar and cooked meat (CM) broth media. CM has been routinely sub-cultured onto solid agar plates after aerobic incubation at 35 °C. This study will evaluate whether a visual assessment of CM can replace sub-culture by an in vitro inoculation and a prospective study. Eight challenge organisms were serially diluted and inoculated into CM. The average inoculum of 0...
January 5, 2017: Cell and Tissue Banking
https://www.readbyqxmd.com/read/28056102/magnetic-particle-imaging-mpi-experimental-quantification-of-vascular-stenosis-using-stationary-stenosis-phantoms
#15
Sarah Vaalma, Jürgen Rahmer, Nikolaos Panagiotopoulos, Robert L Duschka, Jörn Borgert, Jörg Barkhausen, Florian M Vogt, Julian Haegele
Magnetic Particle Imaging (MPI) is able to provide high temporal and good spatial resolution, high signal-to-noise ratio and sensitivity. Furthermore, it is a truly quantitative method as its signal strength is proportional to the concentration of its tracer, superparamagnetic iron oxide nanoparticles (SPIOs). Because of that, MPI is proposed to be a promising future method for cardiovascular imaging. Here, an interesting application may be the quantification of vascular pathologies like stenosis by utilizing the proportionality of the SPIO concentration and the MPI signal strength...
2017: PloS One
https://www.readbyqxmd.com/read/28052549/adsorption-of-norovirus-and-ostreid-herpesvirus-type-1-to-polymer-membranes-for-the-development-of-passive-samplers
#16
Françoise Vincent-Hubert, Benjamin Morga, Tristan Renault, Françoise S Le Guyader
AIMS: This study was performed to develop passive sampling methodology for the detection of two viruses in seawater in the area of shellfish production, The Norovirus (NoV), a human pathogen implicated in gastroenteritis outbreaks linked to oyster consumption and the ostreid herpesvirus type 1 (OsHV-1) a virus associated with mass mortalities of Pacific oysters. METHODS AND RESULTS: Commercially membranes were tested for their capacity to adsorb virus: Zetapor, gauze, nylon, low density polyethylene (LDPE) and Polyvinylidene difluoride (PVDF)...
January 4, 2017: Journal of Applied Microbiology
https://www.readbyqxmd.com/read/28034712/evaluation-of-a-digital-dispenser-for-direct-curve-dilutions-in-a-vaccine-potency-assay
#17
Christopher Roselle, Dana Whitehouse, Thy Follmer, Fran Ansbro, Silikhone Bouaraphan, Liming Guan, Sha-Ke Wang, Mary Shank-Retzlaff, Thorsten Verch
Dilutions are a common source of analytical error, both in terms of accuracy and precision, and a common source of analyst mistakes. When serial dilutions are used, errors compound, even when employing laboratory automation. Direct point dilutions instead of serial dilutions can reduce error but is often impractical as they require either large diluent volumes or very small sample volumes when performed with traditional liquid handling equipment. We evaluated preparation of dilution curves using a picoliter digital dispenser, the HP, Inc...
December 27, 2016: Journal of Immunological Methods
https://www.readbyqxmd.com/read/28027773/ex-vivo-characterization-of-pathologic-fluids-with-quantitative-phase-contrast-computed-tomography
#18
Vivien Richter, Marian S Willner, John Henningsen, Lorenz Birnbacher, Mathias Marschner, Julia Herzen, Melanie A Kimm, Peter B Noe L, Ernst J Rummeny, Franz Pfeiffer, Alexander A Fingerle
PURPOSE: X-ray phase-contrast imaging (PCI) provides additional information beyond absorption characteristics by detecting the phase shift of the X-ray beam passing through material. The grating-based system works with standard polychromatic X-ray sources, promising a possible clinical implementation. PCI has been shown to provide additional information in soft-tissue samples. The aim of this study was to determine if ex vivo quantitative phase-contrast computed tomography (PCCT) may differentiate between pathologic fluid collections...
January 2017: European Journal of Radiology
https://www.readbyqxmd.com/read/28018329/propidium-monoazide-integrated-with-qpcr-enables-the-detection-and-enumeration-of-infectious-enteric-rna-and-dna-viruses-in-clam-and-fermented-sausages
#19
Narciso M Quijada, Gislaine Fongaro, Célia R M Barardi, Marta Hernández, David Rodríguez-Lázaro
The increase of foodborne viral outbreaks highlights the need for a rapid and sensitive method for the prediction of viral infectivity in food samples. This study assesses the use of propidium monoazide (PMA) coupled with real-time PCR methods (RT-qPCR or qPCR for RNA or DNA viruses, respectively) in the determination of viral infectivity in complex animal-related food matrices. Clam and Spanish fermented sausage ("chorizo") samples were spiked with infectious and heat-inactivated human adenovirus-2 (HAdV-2) and mengovirus (vMC0)...
2016: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28012775/comparison-of-functional-assays-used-in-the-clinical-development-of-a-placental-malaria-vaccine
#20
Caroline Pehrson, Kristine K Heno, Yvonne Adams, Mafalda Resende, Line Mathiesen, Max Soegaard, Willem A de Jongh, Thor G Theander, Ali Salanti, Morten A Nielsen
BACKGROUND: Malaria in pregnancy is associated with significant morbidity in pregnant women and their offspring. Plasmodium falciparum infected erythrocytes (IE) express VAR2CSA that mediates binding to chondroitin sulphate A (CSA) in the placenta. Two VAR2CSA-based vaccines for placental malaria are in clinical development. The purpose of this study was to evaluate the robustness and comparability of binding inhibition assays used in the clinical development of placental malaria vaccines...
December 21, 2016: Vaccine
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