Fisher, Matthew C; Ghosh, Pria; Shelton, Jennifer M G; Bates, Kieran; Brookes, Lola; Wierzbicki, Claudia; Rosa, Gonçalo M; Farrer, Rhys A; Aanensen, David M; Alvarado-Rybak, Mario; Bataille, Arnaud; Berger, Lee; Böll, Susanne; Bosch, Jaime; Clare, Frances C; A Courtois, Elodie; Crottini, Angelica; Cunningham, Andrew A; Doherty-Bone, Thomas M; Gebresenbet, Fikirte; Gower, David J; Höglund, Jacob; James, Timothy Y; Jenkinson, Thomas S; Kosch, Tiffany A; Lambertini, Carolina; Laurila, Anssi; Lin, Chun-Fu; Loyau, Adeline; Martel, An; Meurling, Sara; Miaud, Claude; Minting, Pete; Ndriantsoa, Serge; O'Hanlon, Simon J; Pasmans, Frank; Rakotonanahary, Tsanta; Rabemananjara, Falitiana C E; Ribeiro, Luisa P; Schmeller, Dirk S; Schmidt, Benedikt R; Skerratt, Lee; Smith, Freya; Soto-Azat, Claudio; Tessa, Giulia; Toledo, Luís Felipe; Valenzuela-Sánchez, Andrés; Verster, Ruhan; Vörös, Judit; Waldman, Bruce; Webb, Rebecca J; Weldon, Che; Wombwell, Emma; Zamudio, Kelly R; Longcore, Joyce E; Garner, Trenton W J
2018-05-17
Parasitic chytrid fungi have emerged as a significant threat to amphibian species worldwide, necessitating the development of techniques to isolate these pathogens into culture for research purposes. However, early methods of isolating chytrids from their hosts relied on killing amphibians. We modified a pre-existing protocol for isolating chytrids from infected animals to use toe clips and biopsies from toe webbing rather than euthanizing hosts, and distributed the protocol to researchers as part of the BiodivERsA project RACE; here called the RML protocol. In tandem, we developed a lethal procedure for isolating chytrids from tadpole mouthparts. Reviewing a database of use a decade after their inception, we find that these methods have been applied across 5 continents, 23 countries and in 62 amphibian species. Isolation of chytrids by the non-lethal RML protocol occured in 18% of attempts with 207 fungal isolates and three species of chytrid being recovered. Isolation of chytrids from tadpoles occured in 43% of attempts with 334 fungal isolates of one species (Batrachochytrium dendrobatidis) being recovered. Together, these methods have resulted in a significant reduction and refinement of our use of threatened amphibian species and have improved our ability to work with this group of emerging pathogens.
Isolation of bacteria-containing phagosomes by magnetic selection
Lönnbro, Per; Nordenfelt, Pontus; Tapper, Hans
2008-01-01
Background There is a growing awareness of the importance of intracellular events in determining the outcome of infectious disease. To improve the understanding of such events, like phagosome maturation, we set out to develop a versatile technique for phagosome isolation that is rapid and widely applicable to different pathogens. Results We developed two different protocols to isolate phagosomes containing dead or live bacteria modified with small magnetic particles, in conjunction with a synchronized phagocytosis protocol and nitrogen cavitation. For dead bacteria, we performed analysis of the phagosome samples by microscopy and immunoblot, and demonstrated the appearance of maturation markers on isolated phagosomes. Conclusion We have presented detailed protocols for phagosome isolation, which can be adapted for use with different cell types and prey. The versatility and simplicity of the approach allow better control of phagosome isolation, the parameters of which are critical in studies of host-bacteria interaction and phagosome maturation. PMID:18588680
Son, Kiho; Mukherjee, Manali; McIntyre, Brendan A S; Eguez, Jose C; Radford, Katherine; LaVigne, Nicola; Ethier, Caroline; Davoine, Francis; Janssen, Luke; Lacy, Paige; Nair, Parameswaran
2017-10-01
Clinically relevant and reliable reports derived from in vitro research are dependent on the choice of cell isolation protocols adopted between different laboratories. Peripheral blood eosinophils are conventionally isolated using density-gradient centrifugation followed by immunomagnetic selection (positive/negative) while neutrophils follow a more simplified dextran-sedimentation methodology. With the increasing sophistication of molecular techniques, methods are now available that promise protocols with reduced user-manipulations, improved efficiency, and better yield without compromising the purity of enriched cell populations. These recent techniques utilize immunomagnetic particles with multiple specificities against differential cell surface markers to negatively select non-target cells from whole blood, greatly reducing the cost/time taken to isolate granulocytes. Herein, we compare the yield efficiencies, purity and baseline activation states of eosinophils/neutrophils isolated using one of these newer protocols that use immunomagnetic beads (MACSxpress isolation) vs. the standard isolation procedures. The study shows that the MACSxpress method consistently allowed higher yields per mL of peripheral blood compared to conventional methods (P<0.001, n=8, Wilcoxon paired test), with high isolation purities for both eosinophils (95.0±1.7%) and neutrophils (94.2±10.1%) assessed by two methods: Wright's staining and flow cytometry. In addition, enumeration of CD63 + (marker for eosinophil activation) and CD66b + (marker for neutrophil activation) cells within freshly isolated granulocytes, respectively, confirmed that conventional protocols using density-gradient centrifugation caused cellular activation of the granulocytes at baseline compared to the MACSxpress method. In conclusion, MACSxpress isolation kits were found to be superior to conventional techniques for consistent purifications of eosinophils and neutrophils that were suitable for activation assays involving degranulation markers. Copyright © 2017 Elsevier B.V. All rights reserved.
Using Green Star Metrics to Optimize the Greenness of Literature Protocols for Syntheses
ERIC Educational Resources Information Center
Duarte, Rita C. C.; Ribeiro, M. Gabriela T. C.; Machado, Adélio A. S. C.
2015-01-01
A procedure to improve the greenness of a synthesis, without performing laboratory work, using alternative protocols available in the literature is presented. The greenness evaluation involves the separate assessment of the different steps described in the available protocols--reaction, isolation, and purification--as well as the global process,…
METHOD FOR MICRORNA ISOLATION FROM CLINICAL SERUM SAMPLES
Li, Yu; Kowdley, Kris V.
2012-01-01
MicroRNAs are a group of intracellular non-coding RNA molecules that have been implicated in a variety of human diseases. Due to their high stability in blood, microRNAs released into circulation could be potentially utilized as non-invasive biomarkers for diagnosis or prognosis. Current microRNA isolation protocols are specifically designed for solid tissues and are impractical for biomarker development utilizing small-volume serum samples on a large scale. Thus, a protocol for microRNA isolation from serum is needed to accommodate these conditions in biomarker development. To establish such a protocol, we developed a simplified approach to normalize sample input by using single synthetic spike-in microRNA. We evaluated three commonly used commercial microRNA isolation kits for the best performance by comparing RNA quality and yield. The manufacturer’s protocol was further modified to improve the microRNA yield from 200 μL of human serum. MicroRNAs isolated from a large set of clinical serum samples were tested on the miRCURY LNA real-time PCR panel and confirmed to be suitable for high-throughput microRNA profiling. In conclusion, we have established a proven method for microRNA isolation from clinical serum samples suitable for microRNA biomarker development. PMID:22982505
Iskandar, Michèle M.; Lands, Larry C.; Sabally, Kebba; Azadi, Behnam; Meehan, Brian; Mawji, Nadir; Skinner, Cameron D.; Kubow, Stan
2015-01-01
Whey proteins have well-established antioxidant and anti-inflammatory bioactivities. High hydrostatic pressure processing of whey protein isolates increases their in vitro digestibility resulting in enhanced antioxidant and anti-inflammatory effects. This study compared the effects of different digestion protocols on the digestibility of pressurized (pWPI) and native (nWPI) whey protein isolates and the antioxidant and anti-inflammatory properties of the hydrolysates. The pepsin-pancreatin digestion protocol was modified to better simulate human digestion by adjusting temperature and pH conditions, incubation times, enzymes utilized, enzyme-to-substrate ratio and ultrafiltration membrane molecular weight cut-off. pWPI showed a significantly greater proteolysis rate and rate of peptide appearance regardless of digestion protocol. Both digestion methods generated a greater relative abundance of eluting peptides and the appearance of new peptide peaks in association with pWPI digestion in comparison to nWPI hydrolysates. Hydrolysates of pWPI from both digestion conditions showed enhanced ferric-reducing antioxidant power relative to nWPI hydrolysates. Likewise, pWPI hydrolysates from both digestion protocols showed similar enhanced antioxidant and anti-inflammatory effects in a respiratory epithelial cell line as compared to nWPI hydrolysates. These findings indicate that regardless of considerable variations of in vitro digestion protocols, pressurization of WPI leads to more efficient digestion that improves its antioxidant and anti-inflammatory properties. PMID:28231198
Iskandar, Michèle M; Lands, Larry C; Sabally, Kebba; Azadi, Behnam; Meehan, Brian; Mawji, Nadir; Skinner, Cameron D; Kubow, Stan
2015-05-28
Whey proteins have well-established antioxidant and anti-inflammatory bioactivities. High hydrostatic pressure processing of whey protein isolates increases their in vitro digestibility resulting in enhanced antioxidant and anti-inflammatory effects. This study compared the effects of different digestion protocols on the digestibility of pressurized (pWPI) and native (nWPI) whey protein isolates and the antioxidant and anti-inflammatory properties of the hydrolysates. The pepsin-pancreatin digestion protocol was modified to better simulate human digestion by adjusting temperature and pH conditions, incubation times, enzymes utilized, enzyme-to-substrate ratio and ultrafiltration membrane molecular weight cut-off. pWPI showed a significantly greater proteolysis rate and rate of peptide appearance regardless of digestion protocol. Both digestion methods generated a greater relative abundance of eluting peptides and the appearance of new peptide peaks in association with pWPI digestion in comparison to nWPI hydrolysates. Hydrolysates of pWPI from both digestion conditions showed enhanced ferric-reducing antioxidant power relative to nWPI hydrolysates. Likewise, pWPI hydrolysates from both digestion protocols showed similar enhanced antioxidant and anti-inflammatory effects in a respiratory epithelial cell line as compared to nWPI hydrolysates. These findings indicate that regardless of considerable variations of in vitro digestion protocols, pressurization of WPI leads to more efficient digestion that improves its antioxidant and anti-inflammatory properties.
RNA isolation from loquat and other recalcitrant woody plants with high quality and yield.
Morante-Carriel, Jaime; Sellés-Marchart, Susana; Martínez-Márquez, Ascensión; Martínez-Esteso, María José; Luque, Ignacio; Bru-Martínez, Roque
2014-05-01
RNA isolation is difficult in plants that contain large amounts of polysaccharides and polyphenol compounds. To date, no commercial kit has been developed for the isolation of high-quality RNA from tissues with these characteristics, especially for fruit. The common protocols for RNA isolation are tedious and usually result in poor yields when applied to recalcitrant plant tissues. Here an efficient RNA isolation protocol based on cetyltrimethylammonium bromide (CTAB) and two successive precipitations with 10 M lithium chloride (LiCl) was developed specifically for loquat fruits, but it was proved to work efficiently in other tissues of loquat and woody plants. The RNA isolated by this improved protocol was not only of high purity and integrity (A260/A280 ratios ranged from 1.90 to 2.04 and A260/A230 ratios were>2.0) but also of high yield (up to 720 μg on average [coefficient of variation=21%] total RNA per gram fresh tissue). The protocol was tested on loquat fruit (different stages of development, postharvest, ripening, and bruising), leaf, root, flower, stem, and bud; quince fruit and root; grapevine cells in liquid culture; and rose petals. The RNA obtained with this method is amenable to enzymatic treatments and can be efficiently applied for research on gene characterization, expression, and function. Copyright © 2014 Elsevier Inc. All rights reserved.
Borman, Andrew M; Fraser, Mark; Linton, Christopher J; Palmer, Michael D; Johnson, Elizabeth M
2010-06-01
Here, we present a significantly improved version of our previously published method for the extraction of fungal genomic DNA from pure cultures using Whatman FTA filter paper matrix technology. This modified protocol is extremely rapid, significantly more cost effective than our original method, and importantly, substantially reduces the problem of potential cross-contamination between sequential filters when employing FTA technology.
Rod Electroretinograms Elicited by Silent Substitution Stimuli from the Light-Adapted Human Eye
Maguire, John; Parry, Neil R. A.; Kremers, Jan; Kommanapalli, Deepika; Murray, Ian J.; McKeefry, Declan J.
2016-01-01
Purpose To demonstrate that silent substitution stimuli can be used to generate electroretinograms (ERGs) that effectively isolate rod photoreceptor function in humans without the need for dark adaptation, and that this approach constitutes a viable alternative to current clinical standard testing protocols. Methods Rod-isolating and non-isolating sinusoidal flicker stimuli were generated on a 4 primary light-emitting diode (LED) Ganzfeld stimulator to elicit ERGs from participants with normal and compromised rod function who had not undergone dark-adaptation. Responses were subjected to Fourier analysis, and the amplitude and phase of the fundamental were used to examine temporal frequency and retinal illuminance response characteristics. Results Electroretinograms elicited by rod-isolating silent substitution stimuli exhibit low-pass temporal frequency response characteristics with an upper response limit of 30 Hz. Responses are optimal between 5 and 8 Hz and between 10 and 100 photopic trolands (Td). There is a significant correlation between the response amplitudes obtained with the silent substitution method and current standard clinical protocols. Analysis of signal-to-noise ratios reveals significant differences between subjects with normal and compromised rod function. Conclusions Silent substitution provides an effective method for the isolation of human rod photoreceptor function in subjects with normal as well as compromised rod function when stimuli are used within appropriate parameter ranges. Translational Relevance This method of generating rod-mediated ERGs can be achieved without time-consuming periods of dark adaptation, provides improved isolation of rod- from cone-based activity, and will lead to the development of faster clinical electrophysiologic testing protocols with improved selectivity. PMID:27617180
Bartlett, David C; Newsome, Philip N
2017-01-01
Successful hepatocyte isolation is critical for continued development of cellular transplantation. However, most tissue available for research is from diseased liver and the results of hepatocyte isolation from such tissue are inferior compared to normal tissue. Here we describe a modified method, combining the use of Liberase and N-acetylcysteine (NAC), for the isolation of primary human hepatocytes with high viability from normal and diseased liver.
Gagnon, Keith T.; Li, Liande; Janowski, Bethany A.; Corey, David R.
2014-01-01
RNA interference (RNAi) is well known for its ability to regulate gene expression in the cytoplasm of mammalian cells. In mammalian cell nuclei, however, the impact of RNAi has remained more controversial. A key technical hurdle has been a lack of optimized protocols for the isolation and analysis of cell nuclei. Here we describe a simplified protocol for nuclei isolation from cultured cells that incorporates a method for obtaining nucleoplasmic and chromatin fractions and removing cytoplasmic contamination. Cell fractions can then be used to detect the presence and activity of RNAi factors in the nucleus. We present a protocol for investigating an early step in RNAi, Argonaute protein loading with small RNAs, which is enabled by our improved extract preparations. These protocols facilitate characterization of nuclear RNAi and can be applied to the analysis of other nuclear proteins and pathways. From cellular fractionation to analysis of Argonaute loading results, this protocol takes 4–6 d to complete. PMID:25079428
Bova, G Steven; Eltoum, Isam A; Kiernan, John A; Siegal, Gene P; Frost, Andra R; Best, Carolyn J M; Gillespie, John W; Su, Gloria H; Emmert-Buck, Michael R
2005-02-01
Isolation of well-preserved pure cell populations is a prerequisite for sound studies of the molecular basis of any tissue-based biological phenomenon. This article reviews current methods for obtaining anatomically specific signals from molecules isolated from tissues, a basic requirement for productive linking of phenotype and genotype. The quality of samples isolated from tissue and used for molecular analysis is often glossed over or omitted from publications, making interpretation and replication of data difficult or impossible. Fortunately, recently developed techniques allow life scientists to better document and control the quality of samples used for a given assay, creating a foundation for improvement in this area. Tissue processing for molecular studies usually involves some or all of the following steps: tissue collection, gross dissection/identification, fixation, processing/embedding, storage/archiving, sectioning, staining, microdissection/annotation, and pure analyte labeling/identification and quantification. We provide a detailed comparison of some current tissue microdissection technologies, and provide detailed example protocols for tissue component handling upstream and downstream from microdissection. We also discuss some of the physical and chemical issues related to optimal tissue processing, and include methods specific to cytology specimens. We encourage each laboratory to use these as a starting point for optimization of their overall process of moving from collected tissue to high quality, appropriately anatomically tagged scientific results. In optimized protocols is a source of inefficiency in current life science research. Improvement in this area will significantly increase life science quality and productivity. The article is divided into introduction, materials, protocols, and notes sections. Because many protocols are covered in each of these sections, information relating to a single protocol is not contiguous. To get the greatest benefit from this article, readers are advised to read through the entire article first, identify protocols appropriate to their laboratory for each step in their workflow, and then reread entries in each section pertaining to each of these single protocols.
Comparison of seven protocols to identify fecal contamination sources using Escherichia coli
Stoeckel, D.M.; Mathes, M.V.; Hyer, K.E.; Hagedorn, C.; Kator, H.; Lukasik, J.; O'Brien, T. L.; Fenger, T.W.; Samadpour, M.; Strickler, K.M.; Wiggins, B.A.
2004-01-01
Microbial source tracking (MST) uses various approaches to classify fecal-indicator microorganisms to source hosts. Reproducibility, accuracy, and robustness of seven phenotypic and genotypic MST protocols were evaluated by use of Escherichia coli from an eight-host library of known-source isolates and a separate, blinded challenge library. In reproducibility tests, measuring each protocol's ability to reclassify blinded replicates, only one (pulsed-field gel electrophoresis; PFGE) correctly classified all test replicates to host species; three protocols classified 48-62% correctly, and the remaining three classified fewer than 25% correctly. In accuracy tests, measuring each protocol's ability to correctly classify new isolates, ribotyping with EcoRI and PvuII approached 100% correct classification but only 6% of isolates were classified; four of the other six protocols (antibiotic resistance analysis, PFGE, and two repetitive-element PCR protocols) achieved better than random accuracy rates when 30-100% of challenge isolates were classified. In robustness tests, measuring each protocol's ability to recognize isolates from nonlibrary hosts, three protocols correctly classified 33-100% of isolates as "unknown origin," whereas four protocols classified all isolates to a source category. A relevance test, summarizing interpretations for a hypothetical water sample containing 30 challenge isolates, indicated that false-positive classifications would hinder interpretations for most protocols. Study results indicate that more representation in known-source libraries and better classification accuracy would be needed before field application. Thorough reliability assessment of classification results is crucial before and during application of MST protocols.
Microcalli Induction in Protoplasts Isolated from Embryogenic Callus of Date Palm.
Titouh, Khayreddine; Boufis, Nazim; Khelifi, Lakhdar
2017-01-01
Date palm (Phoenix dactylifera L.) production is severely hampered due to several pests and diseases. Biotechnological tools such as protoplast fusion appear as an alternative to ensure rapid genetic improvement and multiplication of this species. However, establishment of an effective system of plant regeneration from protoplasts culture is a prerequisite for date palm somatic hybridization. In this chapter, we describe an effective protocol to induce microcalli in protoplasts isolated from nodular callus of important Algerian date palm cultivars. In this protocol, the main factors influencing the isolation (i.e., enzymatic solution, mannitol concentration, duration, and mode of maceration) of protoplasts from the calli of Algerian date palm cultivars were optimized. Purified protoplasts were cultured on a semisolid medium supplemented with a hormonal balance of auxin and cytokinin to obtain microcalli formation.
Simões, André E S; Pereira, Diane M; Amaral, Joana D; Nunes, Ana F; Gomes, Sofia E; Rodrigues, Pedro M; Lo, Adrian C; D'Hooge, Rudi; Steer, Clifford J; Thibodeau, Stephen N; Borralho, Pedro M; Rodrigues, Cecília M P
2013-03-15
Simultaneous isolation of nucleic acids and proteins from a single biological sample facilitates meaningful data interpretation and reduces time, cost and sampling errors. This is particularly relevant for rare human and animal specimens, often scarce, and/or irreplaceable. TRIzol(®) and TRIzol(®)LS are suitable for simultaneous isolation of RNA, DNA and proteins from the same biological sample. These reagents are widely used for RNA and/or DNA isolation, while reports on their use for protein extraction are limited, attributable to technical difficulties in protein solubilisation. TRIzol(®)LS was used for RNA isolation from 284 human colon cancer samples, including normal colon mucosa, tubulovillous adenomas, and colon carcinomas with proficient and deficient mismatch repair system. TRIzol(®) was used for RNA isolation from human colon cancer cells, from brains of transgenic Alzheimer's disease mice model, and from cultured mouse cortical neurons. Following RNA extraction, the TRIzol(®)-chloroform fractions from human colon cancer samples and from mouse hippocampus and frontal cortex were stored for 2 years and 3 months, respectively, at -80°C until used for protein isolation.Simple modifications to the TRIzol(®) manufacturer's protocol, including Urea:SDS solubilization and sonication, allowed improved protein recovery yield compared to the TRIzol(®) manufacturer's protocol. Following SDS-PAGE and Ponceau and Coomassie staining, recovered proteins displayed wide molecular weight range and staining pattern comparable to those obtainable with commonly used protein extraction protocols. We also show that nuclear and cytosolic proteins can be easily extracted and detected by immunoblotting, and that posttranslational modifications, such as protein phosphorylation, are detectable in proteins recovered from TRIzol(®)-chloroform fractions stored for up to 2 years at -80°C. We provide a novel approach to improve protein recovery from samples processed for nucleic acid extraction with TRIzol(®) and TRIzol(®)LS compared to the manufacturer`s protocol, allowing downstream immunoblotting and evaluation of steady-state relative protein expression levels. The method was validated in large sets of samples from multiple sources, including human colon cancer and brains of transgenic Alzheimer's disease mice model, stored in TRIzol(®)-chloroform for up to two years. Collectively, we provide a faster and cheaper alternative to the TRIzol(®) manufacturer`s protein extraction protocol, illustrating the high relevance, and wide applicability, of the present protein isolation method for the immunoblot evaluation of steady-state relative protein expression levels in samples from multiple sources, and following prolonged storage.
Rodriguez-Canales, Jaime; Hanson, Jeffrey C; Hipp, Jason D; Balis, Ulysses J; Tangrea, Michael A; Emmert-Buck, Michael R; Bova, G Steven
2013-01-01
Isolation of well-preserved pure cell populations is a prerequisite for sound studies of the molecular basis of any tissue-based biological phenomenon. This updated chapter reviews current methods for obtaining anatomically specific signals from molecules isolated from tissues, a basic requirement for productive linking of phenotype and genotype. The quality of samples isolated from tissue and used for molecular analysis is often glossed over or omitted from publications, making interpretation and replication of data difficult or impossible. Fortunately, recently developed techniques allow life scientists to better document and control the quality of samples used for a given assay, creating a foundation for improvement in this area. Tissue processing for molecular studies usually involves some or all of the following steps: tissue collection, gross dissection/identification, fixation, processing/embedding, storage/archiving, sectioning, staining, microdissection/annotation, and pure analyte labeling/identification and quantification. We provide a detailed comparison of some current tissue microdissection technologies and provide detailed example protocols for tissue component handling upstream and downstream from microdissection. We also discuss some of the physical and chemical issues related to optimal tissue processing and include methods specific to cytology specimens. We encourage each laboratory to use these as a starting point for optimization of their overall process of moving from collected tissue to high-quality, appropriately anatomically tagged scientific results. Improvement in this area will significantly increase life science quality and productivity. The chapter is divided into introduction, materials, protocols, and notes subheadings. Because many protocols are covered in each of these sections, information relating to a single protocol is not contiguous. To get the greatest benefit from this chapter, readers are advised to read through the entire chapter first, identify protocols appropriate to their laboratory for each step in their workflow, and then reread entries in each section pertaining to each of these single protocols.
Vedicherla, Srujana; Romanazzo, Sara; Kelly, Daniel J; Buckley, Conor T; Moran, Cathal J
2017-11-28
Purpose/aim of study: Menisectomies account for over 1.5 million surgical interventions in Europe annually, and there is a growing interest in regenerative strategies to improve outcomes in meniscal replacement. The overall objective of this study was to evaluate the role of intraoperatively applied fresh chondrocyte (FC) isolates compared to minced cartilage (MC) fragments, used without cell isolation, to improve bioactivity and tissue integration when combined with a polyurethane replacement. First, to optimize the intraoperative cell isolation protocol, caprine articular cartilage biopsies were digested with 750 U/ml or 3000 U/ml collagenase type II (ratio of 10 ml per g of tissue) for 30 min, 1 h or 12 h with constant agitation and compared to culture-expanded chondrocytes in terms of matrix deposition when cultured on polyurethane scaffolds. Finally, FCs and MC-augmented polyurethane scaffolds were evaluated in a caprine meniscal explant model to assess the potential enhancements on tissue integration strength. Adequate numbers of FCs were harvested using a 30 min chondrocyte isolation protocol and were found to demonstrate improved matrix deposition compared to standard culture-expanded cells in vitro. Upon evaluation in a meniscus explant defect model, both FCs and MC showed improved matrix deposition at the tissue-scaffold interface and enhanced push-out strength, fourfold and 2.5-fold, respectively, compared with the acellular implant. Herein, we have demonstrated a novel approach that could be applied intraoperatively, using FCs or MC for improved tissue integration with a polyurethane meniscal replacement.
Muiños-Bühl, Anixa; González-Recio, Oscar; Muñoz, María; Óvilo, Cristina; García-Casco, Juan; Fernández, Ana I
2018-06-01
There is a growing interest in understanding the role of the gut microbiome on productive and meat quality-related traits in livestock species in order to develop new useful tools for improving pig production systems and industry. Faecal samples are analysed as a proxy of gut microbiota and here the selection of suitable protocols for faecal sampling and DNA isolation is a critical first step in order to obtain reliable results, even more to compare results obtained from different studies. The aim of the current study was to establish in a cost-effective way, using automated ribosomal intergenic spacer analysis technique, a protocol for porcine faecal sampling and storage at farm and slaughterhouse and to determine the most efficient microbiota DNA isolation kit among those most widely used. Operational Taxonomic Unit profiles were compared from Iberian pig faecal samples collected from rectum or ground, stored with liquid N 2 , room temperature or RNAlater, and processed with QIAamp DNA Stool (Qiagen), PowerFecal DNA Isolation (Mobio) or SpeedTools Tissue DNA extraction (Biotools) commercial kits. The results, focused on prokaryote sampling, based on DNA yield and quality, OTU number and Sørensen similarity Indexes, indicate that the recommended protocol for porcine faecal microbiome sampling at farm should include: the collection from porcine rectum to avoid contamination; the storage in liquid N 2 or even at room temperature, but not in RNAlater; and the isolation of microbiota DNA using PowerFecal DNA Isolation kit. These conditions provide more reliable DNA samples for further microbiome analysis.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-03
... the NPIP program. Tentative topics for discussion at the upcoming meetings include: 1. Salmonella enteritidis in meat-type chickens. 2. Salmonella isolation and identification protocol. 3. Notifiable avian...
Isolation and analysis of group 2 innate lymphoid cells in mice.
Moro, Kazuyo; Ealey, Kafi N; Kabata, Hiroki; Koyasu, Shigeo
2015-05-01
Recent studies have identified distinct subsets of innate lymphocytes, collectively called innate lymphoid cells (ILCs), which lack antigen receptor expression but produce various effector cytokines. Group 2 ILCs (ILC2s) respond to epithelial cell-derived cytokines such as interleukin (IL)-25, IL-33 and thymic stromal lymphopoietin (TSLP), produce large amounts of type 2 cytokines, and have a key role in anti-helminth innate immunity and in the pathophysiology of allergic inflammation. The reported phenotypic characteristics of mouse ILC2s vary, depending on the tissue source and preparation method. This protocol describes improved methods for tissue-specific isolation and analysis of mouse ILC2s of high purity and yield from fat tissue, lung, bronchoalveolar lavage fluid (BALF) and small intestine. These improved methods are the result of our thorough investigation of enzymes used for tissue digestion, methods for the elimination of undesired cells, and a combination of antibodies for the detection and isolation of ILC2s. In addition, this new protocol now enables the isolation of ILC2s of high yield, even from inflamed tissues. Depending on the tissue being analyzed, it takes ∼2-4 h for isolation and flow cytometric analysis of ILC2s from the various tissues of a single mouse and ∼4-8 h to sort purified ILC2s from pooled tissues of multiple mice.
Tong, Zhaoguo; Qu, Shenchun; Zhang, Jiyu; Wang, Fei; Tao, Jianmin; Gao, Zhihong; Zhang, Zhen
2012-03-01
RNA extraction is the first step in the study of gene isolation and expression. However, it is difficult to extract high quantity and quality RNA from tissues containing large quantities of polysaccharides and polyphenols. Peach (Prunus persica), in addition to containing high levels of polysaccharides and polyphenols, is a challenging starting material for RNA isolation using a single method because of different amounts of those substances in diverse tissues. Based on three reported methods, we developed a modified RNA isolation protocol to solve this problem, leading to high quality and quantity of total RNA from peach mesocarp tissues of fruits which were sampled from all developmental stages and different storage periods, as well as from other tissues including flowers, leaves, stems, and roots. With our modified method, 28-650 μg of total RNA was routinely obtained from per gram of fresh material, gave at least a 1.16-fold improvement by compared with those isolated by other seven methods. The RNA extracts were successfully used in downstream applications such as RT-PCR, RACE, and real-time PCR.
Di Salvo, Luciana P; Silva, Esdras; Teixeira, Kátia R S; Cote, Rosalba Esquivel; Pereyra, M Alejandra; García de Salamone, Inés E
2014-12-01
Azospirillum is a plant growth-promoting rhizobacteria (PGPR) genus vastly studied and utilized as agriculture inoculants. Isolation of new strains under different environmental conditions allows the access to the genetic diversity and improves the success of inoculation procedures. Historically, the isolation of this genus has been performed by the use of some traditional culture media. In this work we characterized the physiology and biochemistry of five different A. brasilense strains, commonly used as cereal inoculants. The aim of this work is to contribute to pose into revision some concepts concerning the most used protocols to isolate and characterize this bacterium. We characterized their growth in different traditional and non-traditional culture media, evaluated some PGPR mechanisms and characterized their profiles of fatty acid methyl esters and carbon-source utilization. This work shows, for the first time, differences in both profiles, and ACC deaminase activity of A. brasilense strains. Also, we show unexpected results obtained in some of the evaluated culture media. Results obtained here and an exhaustive knowledge revision revealed that it is not appropriate to conclude about bacterial species without analyzing several strains. Also, it is necessary to continue developing studies and laboratory techniques to improve the isolation and characterization protocols. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Robust and effective methodologies for cryopreservation and DNA extraction from anaerobic gut fungi.
Solomon, Kevin V; Henske, John K; Theodorou, Michael K; O'Malley, Michelle A
2016-04-01
Cell storage and DNA isolation are essential to developing an expanded suite of microorganisms for biotechnology. However, many features of non-model microbes, such as an anaerobic lifestyle and rigid cell wall, present formidable challenges to creating strain repositories and extracting high quality genomic DNA. Here, we establish accessible, high efficiency, and robust techniques to store lignocellulolytic anaerobic gut fungi long term without specialized equipment. Using glycerol as a cryoprotectant, gut fungal isolates were preserved for a minimum of 23 months at -80 °C. Unlike previously reported approaches, this improved protocol is non-toxic and rapid, with samples surviving twice as long with negligible growth impact. Genomic DNA extraction for these isolates was optimized to yield samples compatible with next generation sequencing platforms (e.g. Illumina, PacBio). Popular DNA isolation kits and precipitation protocols yielded preps that were unsuitable for sequencing due to carbohydrate contaminants from the chitin-rich cell wall and extensive energy reserves of gut fungi. To address this, we identified a proprietary method optimized for hardy plant samples that rapidly yielded DNA fragments in excess of 10 kb with minimal RNA, protein or carbohydrate contamination. Collectively, these techniques serve as fundamental tools to manipulate powerful biomass-degrading gut fungi and improve their accessibility among researchers. Copyright © 2015 Elsevier Ltd. All rights reserved.
Verma, Digvijay; Satyanarayana, T
2011-09-01
An improved single-step protocol has been developed for extracting pure community humic substance-free DNA from alkaline soils and sediments. The method is based on direct cell lysis in the presence of powdered activated charcoal and polyvinylpolypyrrolidone followed by precipitation with polyethyleneglycol and isopropanol. The strategy allows simultaneous isolation and purification of DNA while minimizing the loss of DNA with respect to other available protocols for metagenomic DNA extraction. Moreover, the purity levels are significant, which are difficult to attain with any of the methods reported in the literature for DNA extraction from soils. The DNA thus extracted was free from humic substances and, therefore, could be processed for restriction digestion, PCR amplification as well as for the construction of metagenomic libraries.
Campoy, Irene; Lanau, Lucia; Altadill, Tatiana; Sequeiros, Tamara; Cabrera, Silvia; Cubo-Abert, Montserrat; Pérez-Benavente, Assumpción; Garcia, Angel; Borrós, Salvador; Santamaria, Anna; Ponce, Jordi; Matias-Guiu, Xavier; Reventós, Jaume; Gil-Moreno, Antonio; Rigau, Marina; Colas, Eva
2016-06-18
Uterine aspirates are used in the diagnostic process of endometrial disorders, yet further applications could emerge if its complex milieu was simplified. Exosome-like vesicles isolated from uterine aspirates could become an attractive source of biomarkers, but there is a need to standardize isolation protocols. The objective of the study was to determine whether exosome-like vesicles exist in the fluid fraction of uterine aspirates and to compare protocols for their isolation, characterization, and analysis. We collected uterine aspirates from 39 pre-menopausal women suffering from benign gynecological diseases. The fluid fraction of 27 of those aspirates were pooled and split into equal volumes to evaluate three differential centrifugation-based procedures: (1) a standard protocol, (2) a filtration protocol, and (3) a sucrose cushion protocol. Characterization of isolated vesicles was assessed by electron microscopy, nanoparticle tracking analysis and immunoblot. Specifically for RNA material, we evaluate the effect of sonication and RNase A treatment at different steps of the protocol. We finally confirmed the efficiency of the selected methods in non-pooled samples. All protocols were useful to isolate exosome-like vesicles. However, the Standard procedure was the best performing protocol to isolate exosome-like vesicles from uterine aspirates: nanoparticle tracking analysis revealed a higher concentration of vesicles with a mode of 135 ± 5 nm, and immunoblot showed a higher expression of exosome-related markers (CD9, CD63, and CD81) thus verifying an enrichment in this type of vesicles. RNA contained in exosome-like vesicles was successfully extracted with no sonication treatment and exogenous nucleic acids digestion with RNaseA, allowing the analysis of the specific inner cargo by Real-Time qPCR. We confirmed the existence of exosome-like vesicles in the fluid fraction of uterine aspirates. They were successfully isolated by differential centrifugation giving sufficient proteomic and transcriptomic material for further analyses. The Standard protocol was the best performing procedure since the other two tested protocols did not ameliorate neither yield nor purity of exosome-like vesicles. This study contributes to establishing the basis for future comparative studies to foster the field of biomarker research in gynecology.
Isolation of high-quality total RNA from leaves of Myrciaria dubia "CAMU CAMU".
Gómez, Juan Carlos Castro; Reátegui, Alina Del Carmen Egoavil; Flores, Julián Torres; Saavedra, Roberson Ramírez; Ruiz, Marianela Cobos; Correa, Sixto Alfredo Imán
2013-01-01
Myrciaria dubia is a main source of vitamin C for people in the Amazon region. Molecular studies of M. dubia require high-quality total RNA from different tissues. So far, no protocols have been reported for total RNA isolation from leaves of this species. The objective of this research was to develop protocols for extracting high-quality total RNA from leaves of M. dubia. Total RNA was purified following two modified protocols developed for leaves of other species (by Zeng and Yang, and by Reid et al.) and one modified protocol developed for fruits of the studied species (by Silva). Quantity and quality of purified total RNA were assessed by spectrophotometric and electrophoretic analysis. Additionally, quality of total RNA was evaluated with reverse-transcription polymerase chain reaction (RT-PCR). With these three modified protocols we were able to isolate high-quality RNA (A260nm/A280nm >1.9 and A260nm/A230nm >2.0). Highest yield was produced with the Zeng and Yang modified protocol (384±46µg ARN/g fresh weight). Furthermore, electrophoretic analysis showed the integrity of isolated RNA and the absence of DNA. Another proof of the high quality of our purified RNA was the successful cDNA synthesis and amplification of a segment of the M. dubia actin 1 gene. We report three modified protocols for isolation total RNA from leaves of M. dubia. The modified protocols are easy, rapid, low in cost, and effective for high-quality and quantity total RNA isolation suitable for cDNA synthesis and polymerase chain reaction.
Titouh, Khayreddine; Khelifi, Lakhdar; Slaoui, Majda; Boufis, Nazim; Morsli, Abdelkader; Hadj Moussa, Khadidja Titouh; Makhzoum, Abdullah
2015-03-01
In Algeria, date palm is currently confronted to the Bayoud disease. Biotechnological tools such as protoplastsfusion can appear as an alternative to ensure rapid multiplication and improvement of this species. Callogenesis induction in protoplasts isolated from embryogenic callus of three date palm cultivars. Some factors influencing the isolation and culture of protoplasts segregated from the calli of three date palm ( Phoenix dactylifera L.) cultivars (Deglet Nour, Akerbouch and Degla Beida) were studied. Protoplasts of each cultivar were cultured on a semi-solid medium supplemented with various hormonal balances. Maceration with an enzymatic solution containing 1.5% cellulase and 1% macerozyme R10 in the presence of 0.5 M mannitol for more than 16 h with gentle agitation allows isolation of a great number of viable protoplasts. In addition, purification of protoplasts on a cushion of 21 or 25% sucrose was effective in cell debris removal and maximum recovery. The culture of isolated protoplasts on a semi-solidified Murashige and Skoog medium, with 0.3% agarose, 2 mg. L -1 2,4-D and 0.5 mg.L -1 BAP allowed good viable protoplast maintenance as well as cell wall regeneration. After more than two months of culture, cell divisions were still occurring and microcalli became visible to the naked eye, containing a large number of cells. The developed protocol can be useful for application of somatic hybridization to improve date palm cultivars.
Andeer, Peter; Strand, Stuart E; Stahl, David A
2012-01-01
Stable-isotope probing (SIP) has proved a valuable cultivation-independent tool for linking specific microbial populations to selected functions in various natural and engineered systems. However, application of SIP to microbial populations with relatively minor buoyant density increases, such as populations that utilize compounds as a nitrogen source, results in reduced resolution of labeled populations. We therefore developed a tandem quantitative PCR (qPCR)-TRFLP (terminal restriction fragment length polymorphism) protocol that improves resolution of detection by quantifying specific taxonomic groups in gradient fractions. This method combines well-controlled amplification with TRFLP analysis to quantify relative taxon abundance in amplicon pools of FAM-labeled PCR products, using the intercalating dye EvaGreen to monitor amplification. Method accuracy was evaluated using mixtures of cloned 16S rRNA genes, DNA extracted from low- and high-G+C bacterial isolates (Escherichia coli, Rhodococcus, Variovorax, and Microbacterium), and DNA from soil microcosms amended with known amounts of genomic DNA from bacterial isolates. Improved resolution of minor shifts in buoyant density relative to TRFLP analysis alone was confirmed using well-controlled SIP analyses.
An improved kilogram-scale preparation of atorvastatin calcium.
Novozhilov, Yuri V; Dorogov, Mikhail V; Blumina, Maria V; Smirnov, Alexey V; Krasavin, Mikhail
2015-01-01
If literature protocols are followed, conversion of an advanced ketal ester intermediate (available in kilogram quantities via a published Paal-Knorr synthesis) to cholesterol-lowering drug atorvastatin calcium is hampered by several process issues, particularly at the final stage where the hemi-calcium salt is obtained. We developed a high-yielding synthesis of atorvastatin calcium salt on 7 kg scale that affords >99.5% product purities by introducing the following key improvements: i. isolating the pure product of the ketal deprotection step as crystalline solid, and ii. using a convenient ethyl acetate extraction procedure to isolate the pure atorvastatin calcium at the ester hydrolysis and counter-ion exchange step. The convenient and operationally simple conversion of an advanced intermediate of atorvastatin to the clinically used hemi-calcium salt form of the drug that is superior to the methods obtainable from the literature is now available to facilitate the production of atorvastatin calcium on industrial scale. Graphical abstractStepwise ketal and tert-butyl ester group hydrolysis and a modified work-up protocol lead to a more convenient preparation of API-grade atorvastatin calcium.
Fallah, F; Minaei Chenar, H; Amiri, H; Omodipour, S; Shirbande Ghods, F; Kahrizi, D; Sohrabi, M; Ghorbani, T; Kazemi, E
2017-02-28
High quality DNA is essential for molecular research. Secondary metabolites can affect the quantity and quality DNA. In current research two DNA isolation methods including CTAB and Delaporta (protocols 1 & 2 respectively) were applied in three leave samples from Cotinus coggygria, Citrus sinensis and Genus juglans that their leaves are rich of secondary metabolites. We successfully isolated DNA from C. coggygria, C. sinensis and Genus Juglans using the two protocols described above. Good quality DNA was isolated from C. coggygria, C. sinensis and Genus Juglans using protocol 1, while protocol 2 failed to produce usable DNA from these sources. The highest amount of DNA (1.3-1.6) was obtained from them using protocol 1. As we discovered, procedure 1 may work better for plants with secondary metabolites.
Higdon, Lauren E; Lee, Karim; Tang, Qizhi; Maltzman, Jonathan S
2016-09-01
Research on human immune responses frequently involves the use of peripheral blood mononuclear cells (PBMC) immediately, or at significantly delayed timepoints, after collection. This requires PBMC isolation from whole blood and cryopreservation for some applications. It is important to standardize protocols for blood collection, PBMC isolation, cryopreservation, and thawing that maximize survival and functionality of PBMC at the time of analysis. This resource includes detailed protocols describing blood collection tubes, isolation of PBMC using a density gradient, cryopreservation of PBMC, and thawing of cells as well as preparation for functional assays. For each protocol, we include important considerations, such as timing, storage temperatures, and freezing rate. In addition, we provide alternatives so that researchers can make informed decisions in determining the optimal protocol for their application.
Nagy, Bálint; Bán, Zoltán; Papp, Zoltán
2005-10-01
The quality and the quantity of isolated DNA have an effect on PCR amplifications. The authors studied three DNA isolation protocols (resin binding method using fresh and frozen amniotic fluid samples, and silica adsorption method using fresh samples) on the quantity and on the quality of the isolated DNA. Amniotic fluid samples were obtained from 20 pregnant women. The isolated DNA concentrations were determined by real-time fluorimeter using SYBRGreen I method. Each sample was studied for the presence of 8 STR markers. The authors compared the number of the detected alleles, electrophoretograms and peak areas. There was a significant difference between the concentration of the obtained DNA and in the peak areas between the three isolation protocols. The numbers of detected alleles were different, we observed the most allele drop outs in the resin type DNA isolation protocol from the fresh sample (detected allele numbers 182), followed by resin binding protocol from the frozen samples (detected allele number 243) and by the silica adsorption method (detected allele number 264). The authors demonstrated that the DNA isolation method has an effect on the quantity and quality of the isolated DNA, and on further PCR amplifications.
Controlling for confounding variables in MS-omics protocol: why modularity matters.
Smith, Rob; Ventura, Dan; Prince, John T
2014-09-01
As the field of bioinformatics research continues to grow, more and more novel techniques are proposed to meet new challenges and improvements upon solutions to long-standing problems. These include data processing techniques and wet lab protocol techniques. Although the literature is consistently thorough in experimental detail and variable-controlling rigor for wet lab protocol techniques, bioinformatics techniques tend to be less described and less controlled. As the validation or rejection of hypotheses rests on the experiment's ability to isolate and measure a variable of interest, we urge the importance of reducing confounding variables in bioinformatics techniques during mass spectrometry experimentation. © The Author 2013. Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.
Protocols for Improvement of Black Pepper (Piper nigrum L.) Utilizing Biotechnological Tools.
Nirmal Babu, K; Divakaran, Minoo; Yamuna, G; Ravindran, P N; Peter, K V
2016-01-01
Black pepper, Piper nigrum L., the "King of spices" is the most widely used spice growing in the South-Western region of India. The humid tropical evergreen forest bordering the Malabar Coast (Western Ghats is one of the hot spot areas of plant bio-diversity on earth) is its center of origin and diversity. However, the crop faces constraints like rampant fungal and viral diseases, lack of disease free planting material, hence biotechnological tools can be utilized to address these problems and strides have been made successfully. The standardization of micropropagation, somatic embryogenesis, in vitro conservation, protoplast isolation, and genetic transformation protocols are described here. The protocols could be utilized to achieve similar goals in the related species of Piper too.
Tsuchida, Sachio; Murata, Syota; Miyabe, Akiko; Satoh, Mamoru; Takiwaki, Masaki; Matsushita, Kazuyuki; Nomura, Fumio
2018-05-01
Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is now a well-established method for identification of microorganisms from positive blood cultures. Pretreatments to effectively remove non-bacterial proteins are a prerequisite for successful identification, and a variety of protocols have been reported. Although commercially available kits, mainly the Sepsityper Kit, are increasingly used, the identification rates reported often are not satisfactory, particularly for Gram-positive isolates. We developed a new, in-house lysis-filtration protocol and prospectively evaluated its performance compared to the Sepsityper kit. The in-house protocol consists of three simple steps: lysis by ammonium chloride, aspiration with a syringe fitted with a 0.45-μm membrane, and centrifugation to collect microbes. The novel protocol requires only 20 min. Performance of the in-house protocol was evaluated using a total of 117 monomicrobial cases of positive blood culture. Medium from blood culture bottles was pretreated by the in-house protocol or the commercial kit, and isolated cells were subjected to direct identification by mass spectrometry fingerprinting in parallel with conventional subculturing for reference identification. The overall MALDI-TOF MS-based identification rates with score > 1.7 and > 2.0 obtained using the in-house protocol were 99.2% and 85.5%, respectively, whereas those obtained using the Sepsityper Kit were 85.4% and 61.5%, respectively. For Gram-positive cases, the in-house protocol yielded scores >1.7 and > 2.0 at 98.5% and 76.1%, respectively, whereas the commercial kit yielded these scores at 76.1% and 43.3%, respectively. Although these are preliminary results, these values suggest that this easy lysis-filtration protocol deserves assessment in a larger-scale test. Copyright © 2018 Elsevier B.V. All rights reserved.
Influenza A Virus Isolation, Culture and Identification
Eisfeld, Amie J.; Neumann, Gabriele; Kawaoka, Yoshihiro
2017-01-01
SUMMARY Influenza A viruses (IAV) cause epidemics and pandemics that result in considerable financial burden and loss of human life. To manage annual IAV epidemics and prepare for future pandemics, improved understanding of how IAVs emerge, transmit, cause disease, and acquire pandemic potential is urgently needed. Fundamental techniques essential for procuring such knowledge are IAV isolation and culture from experimental and surveillance samples. Here, we present a detailed protocol for IAV sample collection and processing, amplification in chicken eggs and mammalian cells, and identification from samples containing unknown pathogens. This protocol is robust, and allows for generation of virus cultures that can be used for downstream analyses. Once experimental or surveillance samples are obtained, virus cultures can be generated and the presence of IAV can be verified in 3–5 days. Increased time-frames may be required for less experienced laboratory personnel, or when large numbers of samples will be processed. PMID:25321410
Baruzzi, Federico; Poltronieri, Palmiro; Quero, Grazia Marina; Morea, Maria; Morelli, Lorenzo
2011-04-01
A method for isolating potential probiotic lactobacilli directly from traditional milk-based foods was developed. The novel digestion/enrichment protocol was set up taking care to minimize the protective effect of milk proteins and fats and was validated testing three commercial fermented milks containing well-known probiotic Lactobacillus strains. Only probiotic bacteria claimed in the label were isolated from two out of three commercial fermented milks. The application of the new protocol to 15 raw milk samples and 6 traditional fermented milk samples made it feasible to isolate 11 potential probiotic Lactobacillus strains belonging to Lactobacillus brevis, Lactobacillus fermentum, Lactobacillus gasseri, Lactobacillus johnsonii, Lactobacillus plantarum, Lactobacillus reuteri, and Lactobacillus vaginalis species. Even though further analyses need to ascertain functional properties of these lactobacilli, the novel protocol set-up makes it feasible to isolate quickly potential probiotic strains from traditional milk-based foods reducing the amount of time required by traditional procedures that, in addition, do not allow to isolate microorganisms occurring as sub-dominant populations.
Advanced tools for the analysis of protein phosphorylation in yeast mitochondria.
Walter, Corvin; Gonczarowska-Jorge, Humberto; Sickmann, Albert; Zahedi, René P; Meisinger, Chris; Schmidt, Oliver
2018-05-24
The biochemical analysis of protein phosphorylation in mitochondria lags behind that of cytosolic signaling events. One reason is the poor stability of many phosphorylation sites during common isolation procedures for mitochondria. We present here an optimized, fast protocol for the purification of yeast mitochondria that greatly increases recovery of phosphorylated mitochondrial proteins. Moreover, we describe improved protocols for the biochemical analysis of mitochondrial protein phosphorylation by Zn 2+ -Phos-tag electrophoresis under both denaturing and - for the first time - native conditions, and demonstrate that they outperform previously applied methods. Copyright © 2018. Published by Elsevier Inc.
USDA-ARS?s Scientific Manuscript database
Mycobacterium avium subsp. paratuberculosis (MAP) is shed into milk and feces of cows with advanced Johne’s disease, allowing transmission of MAP among animals. The objective of this study was to formulate an optimized protocol for the isolation of MAP from milk. Parameters investigated included che...
Comparison of Two Methods of RNA Extraction from Formalin-Fixed Paraffin-Embedded Tissue Specimens
Gouveia, Gisele Rodrigues; Ferreira, Suzete Cleusa; Ferreira, Jerenice Esdras; Siqueira, Sheila Aparecida Coelho; Pereira, Juliana
2014-01-01
The present study aimed to compare two different methods of extracting RNA from formalin-fixed paraffin-embedded (FFPE) specimens of diffuse large B-cell lymphoma (DLBCL). We further aimed to identify possible influences of variables—such as tissue size, duration of paraffin block storage, fixative type, primers used for cDNA synthesis, and endogenous genes tested—on the success of amplification from the samples. Both tested protocols used the same commercial kit for RNA extraction (the RecoverAll Total Nucleic Acid Isolation Optimized for FFPE Samples from Ambion). However, the second protocol included an additional step of washing with saline buffer just after sample rehydration. Following each protocol, we compared the RNA amount and purity and the amplification success as evaluated by standard PCR and real-time PCR. The results revealed that the extra washing step added to the RNA extraction process resulted in significantly improved RNA quantity and quality and improved success of amplification from paraffin-embedded specimens. PMID:25105117
Optimization of Native and Formaldehyde iPOND Techniques for Use in Suspension Cells.
Wiest, Nathaniel E; Tomkinson, Alan E
2017-01-01
The isolation of proteins on nascent DNA (iPOND) technique developed by the Cortez laboratory allows a previously unparalleled ability to examine proteins associated with replicating and newly synthesized DNA in mammalian cells. Both the original, formaldehyde-based iPOND technique and a more recent derivative, accelerated native iPOND (aniPOND), have mostly been performed in adherent cell lines. Here, we describe modifications to both protocols for use with suspension cell lines. These include cell culture, pulse, and chase conditions that optimize sample recovery in both protocols using suspension cells and several key improvements to the published aniPOND technique that reduce sample loss, increase signal to noise, and maximize sample recovery. Additionally, we directly and quantitatively compare the iPOND and aniPOND protocols to test the strengths and limitations of both. Finally, we present a detailed protocol to perform the optimized aniPOND protocol in suspension cell lines. © 2017 Elsevier Inc. All rights reserved.
Martos, Laura; Fernández-Pardo, Álvaro; Oto, Julia; Medina, Pilar; España, Francisco; Navarro, Silvia
2017-01-01
microRNAs are promising biomarkers in biological fluids in several diseases. Different plasma RNA isolation protocols and carriers are available, but their efficiencies have been scarcely compared. Plasma microRNAs were isolated using a phenol and column-based procedure and a column-based procedure, in the presence or absence of two RNA carriers (yeast RNA and MS2 RNA). We evaluated the presence of PCR inhibitors and the relative abundance of certain microRNAs by qRT-PCR. Furthermore, we analyzed the association between different isolation protocols, the relative abundance of the miRNAs in the sample, the GC content and the free energy of microRNAs. In all microRNAs analyzed, the addition of yeast RNA as a carrier in the different isolation protocols used gave lower raw Cq values, indicating higher microRNA recovery. Moreover, this increase in microRNAs recovery was dependent on their own relative abundance in the sample, their GC content and the free-energy of their own most stable secondary structure. Furthermore, the normalization of microRNA levels by an endogenous microRNA is more reliable than the normalization by plasma volume, as it reduced the difference in microRNA fold abundance between the different isolation protocols evaluated. Our thorough study indicates that a standardization of pre- and analytical conditions is necessary to obtain reproducible inter-laboratory results in plasma microRNA studies. PMID:29077772
Bova, G Steven; Eltoum, Isam A; Kiernan, John A; Siegal, Gene P; Frost, Andra R; Best, Carolyn J M; Gillespie, John W; Emmert-Buck, Michael R
2005-01-01
Isolation of well-preserved pure cell populations is a prerequisite for sound studies of the molecular basis of pancreatic malignancy and other biological phenomena. This chapter reviews current methods for obtaining anatomically specific signals from molecules isolated from tissues, a basic requirement for productive linking of phenotype and genotype. The quality of samples isolated from tissue and used for molecular analysis is often glossed-over or omitted from publications, making interpretation and replication of data difficult or impossible. Fortunately, recently developed techniques allow life scientists to better document and control the quality of samples used for a given assay, creating a foundation for improvement in this area. Tissue processing for molecular studies usually involves some or all of the following steps: tissue collection, gross dissection/identification, fixation, processing/embedding, storage/archiving, sectioning, staining, microdissection/annotation, and pure analyte labeling/identification. High-quality tissue microdissection does not necessarily mean high-quality samples to analyze. The quality of biomaterials obtained for analysis is highly dependent on steps upstream and downstream from tissue microdissection. We provide protocols for each of these steps, and encourage you to improve upon these. It is worth the effort of every laboratory to optimize and document its technique at each stage of the process, and we provide a starting point for those willing to spend the time to optimize. In our view, poor documentation of tissue and cell type of origin and the use of nonoptimized protocols is a source of inefficiency in current life science research. Even incremental improvement in this area will increase productivity significantly.
RNA isolation from mouse pancreas: a ribonuclease-rich tissue.
Azevedo-Pouly, Ana Clara P; Elgamal, Ola A; Schmittgen, Thomas D
2014-08-02
Isolation of high-quality RNA from ribonuclease-rich tissue such as mouse pancreas presents a challenge. As a primary function of the pancreas is to aid in digestion, mouse pancreas may contain as much a 75 mg of ribonuclease. We report modifications of standard phenol/guanidine thiocyanate lysis reagent protocols to isolate RNA from mouse pancreas. Guanidine thiocyanate is a strong protein denaturant and will effectively disrupt the activity of ribonuclease under most conditions. However, critical modifications to standard protocols are necessary to successfully isolate RNA from ribonuclease-rich tissues. Key steps include a high lysis reagent to tissue ratio, removal of undigested tissue prior to phase separation and inclusion of a ribonuclease inhibitor to the RNA solution. Using these and other modifications, we routinely isolate RNA with RNA Integrity Number (RIN) greater than 7. The isolated RNA is of suitable quality for routine gene expression analysis. Adaptation of this protocol to isolate RNA from ribonuclease rich tissues besides the pancreas should be readily achievable.
Designing typefaces for maps. A protocol of tests.
NASA Astrophysics Data System (ADS)
Biniek, Sébastien; Touya, Guillaume; Rouffineau, Gilles; Huot-Marchand, Thomas
2018-05-01
The text management in map design is a topic generally linked to placement and composition issues. Whereas the type design issue is rarely addressed or at least only partially. Moreover the typefaces especially designed for maps are rare. This paper presents a protocol of tests to evaluate characters for digital topographic maps and fonts that were designed for the screen through the use of geographical information systems using this protocol. It was launched by the Atelier National de Recherche Typographique Research (ANRT, located in Nancy, France) and took place over his `post-master' course in 2013. The purpose is to isolate different issues inherent to text in a topographic map: map background, nonlinear text placement and toponymic hierarchies. Further research is necessary to improve this kind of approach.
Isolation and culture of human multipotent stromal cells from the pancreas.
Seeberger, Karen L; Eshpeter, Alana; Korbutt, Gregory S
2011-01-01
Mesenchymal stem cells, also termed multipotent mesenchymal stromal cells (MSCs), can be isolated from most adult tissues. Although the exact origin of MSCs expanded from the human pancreas has not been resolved, we have developed protocols to isolate and expand MSCs from human pancreatic tissue that remains after islet procurement. Similar to techniques used to isolate MSCs from bone marrow, pancreatic MSCs are isolated based on their cell adherence, expression of several cell surface antigens, and multilineage differentiation. The protocols for isolating, characterizing, and differentiating MSCs from the pancreas are presented in this chapter.
Nacheva, Elizabeth; Mokretar, Katya; Soenmez, Aynur; Pittman, Alan M; Grace, Colin; Valli, Roberto; Ejaz, Ayesha; Vattathil, Selina; Maserati, Emanuela; Houlden, Henry; Taanman, Jan-Willem; Schapira, Anthony H; Proukakis, Christos
2017-01-01
Potential bias introduced during DNA isolation is inadequately explored, although it could have significant impact on downstream analysis. To investigate this in human brain, we isolated DNA from cerebellum and frontal cortex using spin columns under different conditions, and salting-out. We first analysed DNA using array CGH, which revealed a striking wave pattern suggesting primarily GC-rich cerebellar losses, even against matched frontal cortex DNA, with a similar pattern on a SNP array. The aCGH changes varied with the isolation protocol. Droplet digital PCR of two genes also showed protocol-dependent losses. Whole genome sequencing showed GC-dependent variation in coverage with spin column isolation from cerebellum. We also extracted and sequenced DNA from substantia nigra using salting-out and phenol / chloroform. The mtDNA copy number, assessed by reads mapping to the mitochondrial genome, was higher in substantia nigra when using phenol / chloroform. We thus provide evidence for significant method-dependent bias in DNA isolation from human brain, as reported in rat tissues. This may contribute to array "waves", and could affect copy number determination, particularly if mosaicism is being sought, and sequencing coverage. Variations in isolation protocol may also affect apparent mtDNA abundance.
Nacheva, Elizabeth; Mokretar, Katya; Soenmez, Aynur; Pittman, Alan M.; Grace, Colin; Valli, Roberto; Ejaz, Ayesha; Vattathil, Selina; Maserati, Emanuela; Houlden, Henry; Taanman, Jan-Willem; Schapira, Anthony H.
2017-01-01
Potential bias introduced during DNA isolation is inadequately explored, although it could have significant impact on downstream analysis. To investigate this in human brain, we isolated DNA from cerebellum and frontal cortex using spin columns under different conditions, and salting-out. We first analysed DNA using array CGH, which revealed a striking wave pattern suggesting primarily GC-rich cerebellar losses, even against matched frontal cortex DNA, with a similar pattern on a SNP array. The aCGH changes varied with the isolation protocol. Droplet digital PCR of two genes also showed protocol-dependent losses. Whole genome sequencing showed GC-dependent variation in coverage with spin column isolation from cerebellum. We also extracted and sequenced DNA from substantia nigra using salting-out and phenol / chloroform. The mtDNA copy number, assessed by reads mapping to the mitochondrial genome, was higher in substantia nigra when using phenol / chloroform. We thus provide evidence for significant method-dependent bias in DNA isolation from human brain, as reported in rat tissues. This may contribute to array “waves”, and could affect copy number determination, particularly if mosaicism is being sought, and sequencing coverage. Variations in isolation protocol may also affect apparent mtDNA abundance. PMID:28683077
Isolation of Mouse Pancreatic Islets of Langerhans.
Ramírez-Domínguez, Miriam
The aim of any pancreatic islet isolation is obtaining pure, viable and functional pancreatic islets, either for in vitro or in vivo purposes. The islets of Langerhans are complex microorgans with the important role of regulating glucose homeostasis. Imbalances in glucose homeostasis lead to diabetes, which is defined by the American Diabetes Association as a "group of metabolic diseases characterized by hyperglycemia resulting from defects in insulin secretion, insulin action or both" (American Diabetes Association 2011). Currently, the rising demand of human islets is provoking a shortage of this tissue, limiting research and clinical practice on this field. In this scenario, it is essential to investigate and improve islet isolation procedures in animal models, while keeping in mind the anatomical and functional differences between species. This chapter discusses the main aspects of mouse islet isolation research, highlighting the critical factors and shortcomings to take into account for the selection and/or optimization of a mouse islet isolation protocol.
Lipowska-Bhalla, Grazyna; Gilham, David E; Hawkins, Robert E; Rothwell, Dominic G
2013-12-01
The clinical potential of chimeric antigen receptors in adoptive cellular therapy is beginning to be realized with several recent clinical trials targeting CD19 showing promising results in advanced B cell malignancies. This increased efficacy corresponds with improved engineering of the chimeric receptors with the latest-generation receptors eliciting greater signaling and proliferation potential. However, the antigen-binding single-chain variable fragment (scFv) domain of the receptors is critical in determining the activity of the chimeric receptor-expressing T cells, as this determines specificity and affinity to the tumor antigen. In this study, we describe a mammalian T cell line screening protocol employing a 2A-based bicistronic retroviral vector to isolate functional scFvs. This approach involves expression of the scFv library in a chimeric antigen receptor, and is based on selection of clones capable of stimulating CD69 upregulation in a T cell line and has a number of advantages over previously described methods in that the use of a 2A cassette ensures the exclusion of nonexpressing scFvs and the screening using a chimeric receptor in a mammalian T cell line ensures selection in the optimum context for therapeutic use. Proof-of-principle experiments show that the protocol was capable of a 10(5)-fold enrichment of positive clones after three rounds of selection. Furthermore, an antigen-specific clone was successfully isolated from a partially enriched scFv library, confirming the strength of the protocol. This approach has the potential to identify novel scFvs of use in adoptive T cell therapy and, potentially, wider antibody-based applications.
Ahmad, Norazah; Hoon, Shirley Tang Gee; Ghani, Mohamed Kamel Abd; Tee, Koh Yin
2012-06-01
Serotyping is not sufficient to differentiate between Salmonella species that cause paratyphoid fever from the strains that cause milder gastroenteritis as these organisms share the same serotype Salmonella Paratyphi B (S. Paratyphi B). Strains causing paratyphoid fever do not ferment d-tartrate and this key feature was used in this study to determine the prevalence of these strains among the collection of S. Paratyphi B strains isolated from patients in Malaysia. A total of 105 isolates of S. Paratyphi B were discriminated into d-tartrate positive (dT+) and d-tartrate negative (dT) variants by two lead acetate test protocols and multiplex PCR. The lead acetate test protocol 1 differed from protocol 2 by a lower inoculum size and different incubation conditions while the multiplex PCR utilized 2 sets of primers targeting the ATG start codon of the gene STM3356. Lead acetate protocol 1 discriminated 97.1% of the isolates as S. Paratyphi B dT+ and 2.9% as dT while test protocol 2 discriminated all the isolates as S. Paratyphi B dT+. The multiplex PCR test identified all 105 isolates as S. Paratyphi B dT+ strains. The concordance of the lead acetate test relative to that of multiplex PCR was 97.7% and 100% for protocol 1 and 2 respectively. This study showed that S. Paratyphi B dT+ is a common causative agent of gastroenteritis in Malaysia while paratyphoid fever appears to be relatively uncommon. Multiplex PCR was shown to be a simpler, more rapid and reliable method to discriminate S. Paratyphi B than the phenotypic lead acetate test.
ERIC Educational Resources Information Center
McClellan, Michael J.; Cass, Marion E.
2015-01-01
This communication is a collection of additions and modifications to two previously published classic inorganic synthesis laboratory experiments. The experimental protocol for the synthesis and isolation of enantiomerically enriched ?- (or ?-)Co(en)[subscript 3]I[subscript 3] has been modified to increase reproducibility, yield, and enantiomeric…
Román, Belén; González-Verdejo, Clara I; Peña, Francisco; Nadal, Salvador; Gómez, Pedro
2012-01-01
Quality and integrity of RNA are critical for transcription studies in plant molecular biology. In squash fruit and other high water content crops, the grinding of tissue with mortar and pestle in liquid nitrogen fails to produce a homogeneous and fine powered sample desirable to ensure a good penetration of the extraction reagent. To develop an improved pulverisation method to facilitate the homogenisation process of squash fruit tissue prior to RNA extraction without reducing quality and yield of the extracted RNA. Three methods of pulverisation, each followed by the same extraction protocol, were compared. The first approach consisted of the lyophilisation of the sample in order to remove the excess of water before grinding, the second one used a cryogenic mill and the control one a mortar grinding of frozen tissue. The quality of the isolated RNA was tested by carrying out a quantitative real time downstream amplification. In the three situations considered, mean values for A(260) /A(280) indicated minimal interference by proteins and RNA quality indicator (RQI) values were considered appropriate for quantitative real-time polymerase chain reaction (qRT-PCR) amplification. Successful qRT-PCR amplifications were obtained with cDNA isolated with the three protocols. Both apparatus can improve and facilitate the grinding step in the RNA extraction process in zucchini, resulting in isolated RNA of high quality and integrity as revealed by qRT-PCR downstream application. This is apparently the first time that a cryogenic mill has been used to prepare fruit samples for RNA extraction, thereby improving the sampling strategy because the fine powder obtained represents a homogeneous mix of the organ tissue. Copyright © 2012 John Wiley & Sons, Ltd.
Kupffer Cell Isolation for Nanoparticle Toxicity Testing
Bourgognon, Maxime; Klippstein, Rebecca; Al-Jamal, Khuloud T.
2015-01-01
The large majority of in vitro nanotoxicological studies have used immortalized cell lines for their practicality. However, results from nanoparticle toxicity testing in immortalized cell lines or primary cells have shown discrepancies, highlighting the need to extend the use of primary cells for in vitro assays. This protocol describes the isolation of mouse liver macrophages, named Kupffer cells, and their use to study nanoparticle toxicity. Kupffer cells are the most abundant macrophage population in the body and constitute part of the reticulo-endothelial system (RES), responsible for the capture of circulating nanoparticles. The Kupffer cell isolation method reported here is based on a 2-step perfusion method followed by purification on density gradient. The method, based on collagenase digestion and density centrifugation, is adapted from the original protocol developed by Smedsrød et al. designed for rat liver cell isolation and provides high yield (up to 14 x 106 cells per mouse) and high purity (>95%) of Kupffer cells. This isolation method does not require sophisticated or expensive equipment and therefore represents an ideal compromise between complexity and cell yield. The use of heavier mice (35-45 g) improves the yield of the isolation method but also facilitates remarkably the procedure of portal vein cannulation. The toxicity of functionalized carbon nanotubes f-CNTs was measured in this model by the modified LDH assay. This method assesses cell viability by measuring the lack of structural integrity of Kupffer cell membrane after incubation with f-CNTs. Toxicity induced by f-CNTs can be measured consistently using this assay, highlighting that isolated Kupffer cells are useful for nanoparticle toxicity testing. The overall understanding of nanotoxicology could benefit from such models, making the nanoparticle selection for clinical translation more efficient. PMID:26327223
Martinez-Vaz, Betsy M; Denny, Roxanne; Young, Nevin D; Sadowsky, Michael J
2015-12-01
Microbiology courses often include a laboratory activity on the identification of unknown microbes. This activity consists of providing students with microbial cultures and running biochemical assays to identify the organisms. This approach lacks molecular techniques such as sequencing of genes encoding 16S rRNA, which is currently the method of choice for identification of unknown bacteria. A laboratory activity was developed to teach students how to identify microorganisms using 16S rRNA polymerase chain reaction (PCR) and validate microbial identities using biochemical techniques. We hypothesized that designing an experimental protocol to confirm the identity of a bacterium would improve students' knowledge of microbial identification techniques and the physiological characteristics of bacterial species. Nitrogen-fixing bacteria were isolated from the root nodules of Medicago truncatula and prepared for 16S rRNA PCR analysis. Once DNA sequencing revealed the identity of the organisms, the students designed experimental protocols to verify the identity of rhizobia. An assessment was conducted by analyzing pre- and posttest scores and by grading students' verification protocols and presentations. Posttest scores were higher than pretest scores at or below p = 0.001. Normalized learning gains (G) showed an improvement of students' knowledge of microbial identification methods (LO4, G = 0.46), biochemical properties of nitrogen-fixing bacteria (LO3, G = 0.45), and the events leading to the establishment of nitrogen-fixing symbioses (LO1&2, G = 0.51, G = 0.37). An evaluation of verification protocols also showed significant improvement with a p value of less than 0.001.
Allen, Joselyn N; Dey, Adwitia; Nissly, Ruth; Fraser, James; Yu, Shan; Balandaram, Gayathri; Peters, Jeffrey M; Hankey-Giblin, Pamela A
2017-04-03
Obesity promotes a chronic inflammatory state that is largely mediated by tissue-resident macrophages as well as monocyte-derived macrophages. Diet-induced obesity (DIO) is a valuable model in studying the role of macrophage heterogeneity; however, adequate macrophage isolations are difficult to acquire from inflamed tissues. In this protocol, we outline the isolation steps and necessary troubleshooting guidelines derived from our studies for obtaining a suitable population of tissue-resident macrophages from mice following 18 weeks of high-fat (HFD) or high-fat/high-cholesterol (HFHCD) diet intervention. This protocol focuses on three hallmark tissues studied in obesity and atherosclerosis including the liver, white adipose tissues (WAT), and the aorta. We highlight how dualistic usage of flow cytometry can achieve a new dimension of isolation and characterization of tissue-resident macrophages. A fundamental section of this protocol addresses the intricacies underlying tissue-specific enzymatic digestions and macrophage isolation, and subsequent cell-surface antibody staining for flow cytometric analysis. This protocol addresses existing complexities underlying fluorescent-activated cell sorting (FACS) and presents clarifications to these complexities so as to obtain broad range characterization from adequately sorted cell populations. Alternate enrichment methods are included for sorting cells, such as the dense liver, allowing for flexibility and time management when working with FACS. In brief, this protocol aids the researcher to evaluate macrophage heterogeneity from a multitude of inflamed tissues in a given study and provides insightful troubleshooting tips that have been successful for favorable cellular isolation and characterization of immune cells in DIO-mediated inflammation.
Isolated cleft palate requires different surgical protocols depending on cleft type.
Elander, Anna; Persson, Christina; Lilja, Jan; Mark, Hans
2017-08-01
A staged protocol for isolated cleft palate (CPO), comprising the early repair of the soft palate at 6 months and delayed repair of the eventual cleft in the hard palate until 4 years, designed to improve maxillary growth, was introduced. CPO is frequently associated with additional congenital conditions. The study evaluates this surgical protocol for clefts in the soft palate (CPS) and for clefts in the hard and soft palate (CPH), with or without additional malformation, regarding primary and secondary surgical interventions needed for cleft closure and for correction of velopharyngeal insufficiency until 10 years of age. Of 94 consecutive children with CPO, divided into four groups with (+) or without (-) additional malformations (CPS + or CPS - and CPH + or CPH-), hard palate repair was required in 53%, performed with small local flaps in 21% and with bilateral mucoperiosteal flaps in 32%. The total incidence of soft palate re-repair was 2% and the fistula repair of the hard palate was 5%. The total incidence of secondary velopharyngeal surgery was 17% until 10 years, varying from 0% for CPS - and 15% for CPH-, to 28% for CPS + and 30% for CPH+. The described staged protocol for repair of CPO is found to be safe in terms of perioperative surgical results, with comparatively low need for secondary interventions. Furthermore, the study indicates that the presence of a cleft in the hard palate and/or additional conditions have a negative impact on the development of the velopharyngeal function.
Rizzo, Antonio; Trauner, Dirk
2018-04-06
An approach toward (-)-enterocin, an antibiotic isolated from Streptomyces hygroscopicus, is described. Its compact, heavily oxidized protoadamantane core represents a daunting challenge for an efficient synthesis. Convergent assembly of its 2-oxabicyclo[3.3.1]nonane core with a cuprate-mediated Barbier reaction is disclosed. Its functionalization to a suitable substrate for a biomimetic aldol to close the final ring of the natural product is evaluated.
Expression microdissection adapted to commercial laser dissection instruments
Hanson, Jeffrey C; Tangrea, Michael A; Kim, Skye; Armani, Michael D; Pohida, Thomas J; Bonner, Robert F; Rodriguez-Canales, Jaime; Emmert-Buck, Michael R
2016-01-01
Laser-based microdissection facilitates the isolation of specific cell populations from clinical or animal model tissue specimens for molecular analysis. Expression microdissection (xMD) is a second-generation technology that offers considerable advantages in dissection capabilities; however, until recently the method has not been accessible to investigators. This protocol describes the adaptation of xMD to commonly used laser microdissection instruments and to a commercially available handheld laser device in order to make the technique widely available to the biomedical research community. The method improves dissection speed for many applications by using a targeting probe for cell procurement in place of an operator-based, cell-by-cell selection process. Moreover, xMD can provide improved dissection precision because of the unique characteristics of film activation. The time to complete the protocol is highly dependent on the target cell population and the number of cells needed for subsequent molecular analysis. PMID:21412274
Silva, Rodrigo O S; Almeida, Lara R; Oliveira Junior, Carlos A; Lima, Paula C S; Soares, Danielle F M; Pereira, Pedro L L; Silva, Israel J; Lobato, Francisco C F
2016-03-01
The importance of Clostridium perfringens for most wild animal species remains unclear. This study aimed to isolate and genotype C. perfringens in stool samples from free-living South American coati (Nasua nasua) in Brazil. Forty-six free-living N. nasua were trapped and stool samples were collected. Two different protocols for C. perfringens isolation were tested: direct plating onto selective agar and pre-enrichment in broth followed by plating in selective agar. Clostridium perfringens type A was isolated from 15 (32.6%) animals by direct plating and 36 (78.3%) animals by broth PE, and the rate of isolation was significantly different between these two methods (P < 0.01). Twelve of the 36 (33.3%) isolated strains by the PE protocol were positive for the β-2 toxin-encoding gene (cpb2) whereas the enterotoxin-encoding gene (cpe) and necrotic enteritis like-B toxin gene (netb) were not found. These results suggest that C. perfringens is commonly part of the microbiota of free-living coatis. Additionally, the use of a PE protocol appears to be essential for studies on C. perfringens in this species.
A biochemical protocol for the isolation and identification of current species of Vibrio in seafood.
Ottaviani, D; Masini, L; Bacchiocchi, S
2003-01-01
We report a biochemical method for the isolation and identification of the current species of vibrios using just one operative protocol. The method involves an enrichment phase with incubation at 30 degrees C for 8-24 h in alkaline peptone water and an isolation phase on thiosulphate-citrate-salt sucrose agar plates incubating at 30 degrees C for 24 h. Four biochemical tests and Alsina's scheme were performed for genus and species identification, respectively. All biochemical tests were optimized as regards conditions of temperature, time of incubation and media composition. The whole standardized protocol was always able to give a correct identification when applied to 25 reference strains of Vibrio and 134 field isolates. The data demonstrated that the assay method allows an efficient recovery, isolation and identification of current species of Vibrio in seafood obtaining results within 2-7 days. This method based on biochemical tests could be applicable even in basic microbiology laboratories, and can be used simultaneously to isolate and discriminate all clinically relevant species of Vibrio.
Scollo, Francesco; Egea, Leticia A; Gentile, Alessandra; La Malfa, Stefano; Dorado, Gabriel; Hernandez, Pilar
2016-12-15
Olive oil is considered a premium product for its nutritional value and health benefits, and the ability to define its origin and varietal composition is a key step towards ensuring the traceability of the product. However, isolating the DNA from such a matrix is a difficult task. In this study, the quality and quantity of olive oil DNA, isolated using four different DNA isolation protocols, was evaluated using the qRT-PCR and ddPCR techniques. The results indicate that CTAB-based extraction methods were the best for unfiltered oil, while Nucleo Spin-based extraction protocols showed greater overall reproducibility. The use of both qRT-PCR and ddPCR led to the absolute quantification of the DNA copy number. The results clearly demonstrate the importance of the choice of DNA-isolation protocol, which should take into consideration the qualitative aspects of DNA and the evaluation of the amplified DNA copy number. Copyright © 2016 Elsevier Ltd. All rights reserved.
Head, Stewart I.; Greenaway, Bronwen; Chan, Stephen
2011-01-01
Background Creatine supplementation can improve performance during high intensity exercise in humans and improve muscle strength in certain myopathies. In this present study, we investigated the direct effects of acute creatine incubation on isolated mouse fast-twitch EDL muscles, and examined how these effects change with fatigue. Methods and Results The extensor digitorum longus muscle from mice aged 12–14 weeks was isolated and stimulated with field electrodes to measure force characteristics in 3 different states: (i) before fatigue; (ii) immediately after a fatigue protocol; and (iii) after recovery. These served as the control measurements for the muscle. The muscle was then incubated in a creatine solution and washed. The measurement of force characteristics in the 3 different states was then repeated. In un-fatigued muscle, creatine incubation increased the maximal tetanic force. In fatigued muscle, creatine treatment increased the force produced at all frequencies of stimulation. Incubation also increased the rate of twitch relaxation and twitch contraction in fatigued muscle. During repetitive fatiguing stimulation, creatine-treated muscles took 55.1±9.5% longer than control muscles to lose half of their original force. Measurement of weight changes showed that creatine incubation increased EDL muscle mass by 7%. Conclusion Acute creatine application improves force production in isolated fast-twitch EDL muscle, and these improvements are particularly apparent when the muscle is fatigued. One likely mechanism for this improvement is an increase in Ca2+ sensitivity of contractile proteins as a result of ionic strength decreases following creatine incubation. PMID:21850234
Girsowicz, Elie; Falcoz, Pierre-Emmanuel; Santelmo, Nicola; Massard, Gilbert
2012-03-01
A best evidence topic was constructed according to a structured protocol. The question addressed was whether surgical stabilization is effective in improving the outcomes of patients with isolated multiple distracted and painful non-flail rib fractures. Of the 356 papers found using a report search, nine presented the best evidence to answer the clinical question. The authors, journal, date and country of publication, study type, group studied, relevant outcomes and results of these papers are given. We conclude that, on the whole, the nine retrieved studies clearly support the use of surgical stabilization in the management of isolated multiple non-flail and painful rib fractures for improving patient outcomes. The interest and benefit was shown not only in terms of pain (McGill pain questionnaire) and respiratory function (forced vital capacity, forced expiratory volume in 1 s and carbon monoxide diffusing capacity), but also in improved quality of life (RAND 36-Item Health Survey) and reduced socio-professional disability. Indeed, most of the authors justified surgical management based on the fact that the results of surgical stabilization showed improvement in short- and long-term patient outcomes, with fast reduction in pain and disability, as well as lower average wait before recommencing normal activities. Hence, the current evidence shows surgical stabilization to be safe and effective in alleviating post-operative pain and in improving patient recovery, thus enhancing the outcome after isolated multiple rib fractures. However, given the little published evidence, prospective trials are necessary to confirm these encouraging results.
Morris, Renée; Mehta, Prachi
2018-01-01
In mammals, the central nervous system (CNS) is constituted of various cellular elements, posing a challenge to isolating specific cell types to investigate their expression profile. As a result, tissue homogenization is not amenable to analyses of motor neurons profiling as these represent less than 10% of the total spinal cord cell population. One way to tackle the problem of tissue heterogeneity and obtain meaningful genomic, proteomic, and transcriptomic profiling is to use laser capture microdissection technology (LCM). In this chapter, we describe protocols for the capture of isolated populations of motor neurons from spinal cord tissue sections and for downstream transcriptomic analysis of motor neurons with RT-PCR. We have also included a protocol for the immunological confirmation that the captured neurons are indeed motor neurons. Although focused on spinal cord motor neurons, these protocols can be easily optimized for the isolation of any CNS neurons.
Laget, Sophie; Broncy, Lucile; Hormigos, Katia; Dhingra, Dalia M; BenMohamed, Fatima; Capiod, Thierry; Osteras, Magne; Farinelli, Laurent; Jackson, Stephen; Paterlini-Bréchot, Patrizia
2017-01-01
Circulating Tumor Cells (CTC) and Circulating Tumor Microemboli (CTM) are Circulating Rare Cells (CRC) which herald tumor invasion and are expected to provide an opportunity to improve the management of cancer patients. An unsolved technical issue in the CTC field is how to obtain highly sensitive and unbiased collection of these fragile and heterogeneous cells, in both live and fixed form, for their molecular study when they are extremely rare, particularly at the beginning of the invasion process. We report on a new protocol to enrich from blood live CTC using ISET® (Isolation by SizE of Tumor/Trophoblastic Cells), an open system originally developed for marker-independent isolation of fixed tumor cells. We have assessed the impact of our new enrichment method on live tumor cells antigen expression, cytoskeleton structure, cell viability and ability to expand in culture. We have also explored the ISET® in vitro performance to collect intact fixed and live cancer cells by using spiking analyses with extremely low number of fluorescent cultured cells. We describe results consistently showing the feasibility of isolating fixed and live tumor cells with a Lower Limit of Detection (LLOD) of one cancer cell per 10 mL of blood and a sensitivity at LLOD ranging from 83 to 100%. This very high sensitivity threshold can be maintained when plasma is collected before tumor cells isolation. Finally, we have performed a comparative next generation sequencing (NGS) analysis of tumor cells before and after isolation from blood and culture. We established the feasibility of NGS analysis of single live and fixed tumor cells enriched from blood by our system. This study provides new protocols for detection and characterization of CTC collected from blood at the very early steps of tumor invasion.
Griffeth, Richard J.; García-Párraga, Daniel; Mellado-López, Maravillas; Crespo-Picazo, Jose Luis; Soriano-Navarro, Mario; Martinez-Romero, Alicia; Moreno-Manzano, Victoria
2014-01-01
Dolphins exhibit an extraordinary capacity to heal deep soft tissue injuries. Nevertheless, accelerated wound healing in wild or captive dolphins would minimize infection and other side effects associated with open wounds in marine animals. Here, we propose the use of a biological-based therapy for wound healing in dolphins by the application of platelet-rich plasma (PRP). Blood samples were collected from 9 different dolphins and a specific and simple protocol which concentrates platelets greater than two times that of whole blood was developed. As opposed to a commonly employed human protocol for PRP preparation, a single centrifugation for 3 minutes at 900 rpm resulted in the best condition for the concentration of dolphin platelets. By FACS analysis, dolphin platelets showed reactivity to platelet cell-surface marker CD41. Analysis by electron microscopy revealed that dolphin platelets were larger in size than human platelets. These findings may explain the need to reduce the duration and speed of centrifugation of whole blood from dolphins to obtain a 2-fold increase and maintain proper morphology of the platelets. For the first time, levels of several growth factors from activated dolphin platelets were quantified. Compared to humans, concentrations of PDGF-BB were not different, while TGFβ and VEGF-A were significantly lower in dolphins. Additionally, adipose tissue was obtained from cadaveric dolphins found along the Spanish Mediterranean coast, and adipose-derived mesenchymal stem cells (ASCs) were successfully isolated, amplified, and characterized. When dolphin ASCs were treated with 2.5 or 5% dolphin PRP they exhibited significant increased proliferation and improved phagocytotic activity, indicating that in culture, PRP may improve the regenerative capacity of ASCs. Taken together, we show an effective and well-defined protocol for efficient PRP isolation. This protocol alone or in combination with ASCs, may constitute the basis of a biological treatment for wound-healing and tissue regeneration in dolphins. PMID:25251412
Griffeth, Richard J; García-Párraga, Daniel; Mellado-López, Maravillas; Crespo-Picazo, Jose Luis; Soriano-Navarro, Mario; Martinez-Romero, Alicia; Moreno-Manzano, Victoria
2014-01-01
Dolphins exhibit an extraordinary capacity to heal deep soft tissue injuries. Nevertheless, accelerated wound healing in wild or captive dolphins would minimize infection and other side effects associated with open wounds in marine animals. Here, we propose the use of a biological-based therapy for wound healing in dolphins by the application of platelet-rich plasma (PRP). Blood samples were collected from 9 different dolphins and a specific and simple protocol which concentrates platelets greater than two times that of whole blood was developed. As opposed to a commonly employed human protocol for PRP preparation, a single centrifugation for 3 minutes at 900 rpm resulted in the best condition for the concentration of dolphin platelets. By FACS analysis, dolphin platelets showed reactivity to platelet cell-surface marker CD41. Analysis by electron microscopy revealed that dolphin platelets were larger in size than human platelets. These findings may explain the need to reduce the duration and speed of centrifugation of whole blood from dolphins to obtain a 2-fold increase and maintain proper morphology of the platelets. For the first time, levels of several growth factors from activated dolphin platelets were quantified. Compared to humans, concentrations of PDGF-BB were not different, while TGFβ and VEGF-A were significantly lower in dolphins. Additionally, adipose tissue was obtained from cadaveric dolphins found along the Spanish Mediterranean coast, and adipose-derived mesenchymal stem cells (ASCs) were successfully isolated, amplified, and characterized. When dolphin ASCs were treated with 2.5 or 5% dolphin PRP they exhibited significant increased proliferation and improved phagocytotic activity, indicating that in culture, PRP may improve the regenerative capacity of ASCs. Taken together, we show an effective and well-defined protocol for efficient PRP isolation. This protocol alone or in combination with ASCs, may constitute the basis of a biological treatment for wound-healing and tissue regeneration in dolphins.
A Novel Method for Isolation of Pluripotent Stem Cells from Human Umbilical Cord Blood.
Monti, Manuela; Imberti, Barbara; Bianchi, Niccolò; Pezzotta, Anna; Morigi, Marina; Del Fante, Claudia; Redi, Carlo Alberto; Perotti, Cesare
2017-09-01
Very small embryonic-like cells (VSELs) are a population of very rare pluripotent stem cells isolated in adult murine bone marrow and many other tissues and organs, including umbilical cord blood (UCB). VSEL existence is still not universally accepted by the scientific community, so for this purpose, we sought to investigate whether presumptive VSELs (pVSELs) could be isolated from human UCB with an improved protocol based on the isolation of enriched progenitor cells by depletion of nonprogenitor cells with magnetic separation. Progenitor cells, likely including VSELs, cultured with retinoic acid were able to form dense colonies and cystic embryoid bodies and to differentiate toward the ecto-meso-endoderm lineages as shown by the positivity to specific markers. VSEL differentiative potential toward mesodermal lineage was further demonstrated in vitro upon exposure to an established inductive protocol, which induced the acquisition of renal progenitor cell phenotype. VSEL-derived renal progenitors showed regenerative potential in a cisplatin model of acute kidney injury by restoring renal function and tubular structure through induction of proliferation of endogenous renal cells. The data presented here foster the great debate that surrounds VSELs and, more in general, the existence of cells endowed with pluripotent features in adult tissues. In fact, the possibility to find and isolate subpopulations of cells that fully fit all the criteria utilized to define pluripotency remains, nowadays, almost unproven. Thus, efforts to better characterize the phenotype of these intriguing cells are crucial to understand their possible applications for regenerative and precision medicine purposes.
Faisal, M.; Eissa, A.E.; Starliper, C.E.
2010-01-01
Renibacterium salmoninarum, the causative agent of bacterial kidney disease (BKD), is a fastidious and slow-growing bacterium that is extremely difficult to grow in vitro. Herein, we describe a modified primary culture protocol that encompasses a modified bacteriological culture medium and a tissue processing procedure. In order to facilitate the release of R. salmoninarum from granulomatous tissues, kidneys of infected fish were homogenized in a high speed stomacher. The kidney disease medium (KDM2), routinely used for primary culture of R. salmoninarum was modified by the addition of antibiotics and metabolites. When a relatively large inoculum of diluted kidney homogenate was streak-plate inoculated onto the modified KDM2, colonial growth of R. salmoninarum was achieved within 5-7. days, compared to the standard of two weeks or more. The modified procedure was then used to determine the prevalence of R. salmoninarum among representative captive and feral salmonid stocks in Michigan. Prevalence and clinical manifestations varied among species, strains of fish, and locations; however, R. salmoninarum isolates were biochemically homogenous. The improved primary culture procedure described in this study enabled selective and quick isolation of R. salmoninarum. Also, the isolates retrieved in this study constitute a unique biological resource for future studies of R. salmoninarum in the Laurentian Great Lakes. ?? 2009 University of Cairo.
Bertone, I; Bellino, C; Alborali, G L; Cagnasso, A; Cagnotti, G; Dappiano, E; Lizzi, M; Miciletta, M; Ramacciotti, A; Gianella, P; D'Angelo, A
2015-12-03
The aims of this field trial were to describe the clinical-pathologic findings in calves with otitis media (OM) and media-interna (OMI), to evaluate, through the development of a scoring system, the effectiveness of a standardized therapeutic protocol, and to identify the causative pathogens and their possible correlation with concurrent respiratory disease. All animals underwent physical and neurological examinations at three experimental time points: at diagnosis/beginning of treatment (T0), 1 week (T1) and 2 weeks (T2) after therapy was started, respectively. Follow-up telephone interviews with animal owners were conducted 1 month later. The therapeutic protocol consisted of tulathromycin (Draxxin®; Zoetis), oxytetracycline hydrochloride (Terramicina 100®; Zoetis), and carprofen (Rimadyl®; Zoetis). Twenty-two calves were enrolled. Physical and otoscopic examination at T0 revealed monolateral and bilateral otorrhea in 16 and 6 calves, respectively, with peripheral vestibular system involvement in calves presenting with neurological signs (n = 17; 77 %). A significant improvement of clinical and neurological scores was observed in 20 (90 %) calves, a full recovery in only 1 (5 %). One calf worsened between T0 and T1 and it was removed from the study. None of the other animals showed a worsening of clinical conditions and/or required further treatments at one month follow up. Mycoplasma bovis was isolated in 89 % of the affected ears either alone or together with P. multocida (n = 5), Streptococcus spp. (n = 1), Staphylococcus spp. (n = 1), and Pseudomonas spp. (n = 1). M. bovis either alone or together with these bacteria was also isolated from the upper and/or lower respiratory tract in 19 (86 %) calves. This is the first prospective study to evaluate the effectiveness of a standardized therapeutic protocol for the treatment of OM/OMI in calves. The therapy led to clinical improvement in the majority of the calves. Persistence of mild clinical-neurological signs did not compromise productive performance. The numerical scoring system for clinical and neurological signs permitted objective evaluation of response to therapy. M. bovis was the pathogen most often isolated. This finding should be considered in the treatment of OM/OMI in calves. Moreover, respiratory tract infection should not be underrated, since it is one of the major risk factors for the development of OM/OMI.
Isolation and purification of rabbit mesenchymal stem cells using an optimized protocol.
Lin, Chunbo; Shen, Maorong; Chen, Weiping; Li, Xiaofeng; Luo, Daoming; Cai, Jinhong; Yang, Yuan
2015-11-01
Mesenchymal stem cells were first isolated and grown in vitro by Friedenstein over 40 yr ago; however, their isolation remains challenging as they lack unique markers for identification and are present in very small quantities in mesenchymal tissues and bone marrow. Using whole marrow samples, common methods for mesenchymal stem cell isolation are the adhesion method and density gradient fractionation. The whole marrow sample adhesion method still results in the nonspecific isolation of mononuclear cells, and activation and/or potential loss of target cells. Density gradient fractionation methods are complicated, and may result in contamination with toxic substances that affect cell viability. In the present study, we developed an optimized protocol for the isolation and purification of mesenchymal stem cells based on the principles of hypotonic lysis and natural sedimentation.
Robust DNA Isolation and High-throughput Sequencing Library Construction for Herbarium Specimens.
Saeidi, Saman; McKain, Michael R; Kellogg, Elizabeth A
2018-03-08
Herbaria are an invaluable source of plant material that can be used in a variety of biological studies. The use of herbarium specimens is associated with a number of challenges including sample preservation quality, degraded DNA, and destructive sampling of rare specimens. In order to more effectively use herbarium material in large sequencing projects, a dependable and scalable method of DNA isolation and library preparation is needed. This paper demonstrates a robust, beginning-to-end protocol for DNA isolation and high-throughput library construction from herbarium specimens that does not require modification for individual samples. This protocol is tailored for low quality dried plant material and takes advantage of existing methods by optimizing tissue grinding, modifying library size selection, and introducing an optional reamplification step for low yield libraries. Reamplification of low yield DNA libraries can rescue samples derived from irreplaceable and potentially valuable herbarium specimens, negating the need for additional destructive sampling and without introducing discernible sequencing bias for common phylogenetic applications. The protocol has been tested on hundreds of grass species, but is expected to be adaptable for use in other plant lineages after verification. This protocol can be limited by extremely degraded DNA, where fragments do not exist in the desired size range, and by secondary metabolites present in some plant material that inhibit clean DNA isolation. Overall, this protocol introduces a fast and comprehensive method that allows for DNA isolation and library preparation of 24 samples in less than 13 h, with only 8 h of active hands-on time with minimal modifications.
Novel method for the rapid isolation of RPE cells specifically for RNA extraction and analysis
Wang, Cynthia Xin-Zhao; Zhang, Kaiyan; Aredo, Bogale; Lu, Hua; Ufret-Vincenty, Rafael L.
2012-01-01
RPE cells are involved in the pathogenesis of many retinal diseases. Accurate analysis of RPE gene expression profiles in different scenarios will increase our understanding of disease mechanisms. Our objective in this study was to develop an improved method for the isolation of RPE cells, specifically for RNA analysis. Mouse RPE cells were isolated using different techniques, including mechanical dissociation techniques and a new technique we refer to here as “Simultaneous RPE cell Isolation and RNA Stabilization” (SRIRS method). RNA was extracted from the RPE cells. An RNA bioanalyzer was used to determine the quantity and quality of RNA. qPCR was used to determine contamination with non-RPE-derived RNA. Several parameters with a potential impact on the isolation protocol were studied and optimized. A marked improvement in the quantity and quality of RPE-derived RNA was obtained with the SRIRS technique. We could get the RPE in direct contact with the RNA protecting agent within 1 minute of enucleation, and the RPE isolated within 11 minutes of enucleation. There was no significant contamination with vascular, choroidal or scleral-derived RNA. We have developed a fast, easy and reliable method for the isolation of RPE cells that leads to a high yield of RPE-derived RNA while preserving its quality. We believe this technique will be useful for future studies looking at gene expression profiles of RPE cells and their role in the pathophysiology of retinal diseases. PMID:22721721
Evaluation of a postexposure rabies prophylaxis protocol for domestic animals in Texas: 2000-2009.
Wilson, Pamela J; Oertli, Ernest H; Hunt, Patrick R; Sidwa, Thomas J
2010-12-15
To determine whether postexposure rabies prophylaxis (PEP) in domestic animals, as mandated in Texas, has continued to be effective and to evaluate preexposure or postexposure vaccination failures from 2000 through 2009. Retrospective case series. 1,014 unvaccinated domestic animals (769 dogs, 126 cats, 72 horses, 39 cattle, 3 sheep, 4 goats, and 1 llama) that received PEP and 12 vaccinated domestic animals (7 dogs and 5 cats) with possible failure of protection. Zoonotic incident reports from 2000 through 2009 were reviewed for information regarding unvaccinated domestic animals that received PEP in accordance with the state protocol after exposure to a laboratory-confirmed rabid animal; reports also were reviewed for any preexposure or postexposure vaccination failures. The state-required PEP protocol was as follows: immediately vaccinate the animal against rabies, isolate the animal for 90 days, and administer booster vaccinations during the third and eighth weeks of the isolation period. From 2000 through 2009, 1,014 animals received PEP; no failures were recorded. One preexposure vaccination failure was recorded. The Texas PEP protocol was used during the 10-year period. Results indicated that an effective PEP protocol for unvaccinated domestic animals exposed to rabies was immediate vaccination against rabies, a strict isolation period of 90 days, and administration of booster vaccinations during the third and eighth weeks of the isolation period.
A rapid and efficient SDS-based RNA isolation protocol from different tissues of coffee.
Huded, Arun Kumar C; Jingade, Pavankumar; Mishra, Manoj Kumar
2018-03-01
Isolation of high-quality RNA from coffee is challenging because of high level of polysaccharides, polyphenols and other secondary metabolites. In the present study, a rapid and efficient RNA extraction protocol from different tissues of coffee was optimized. Sufficiently high quality and quantity (225.6-454.8 µg/g) of RNA was obtained by using the optimized protocol. The presence of two distinct bands of 28S rRNA and 18S rRNA in agarose gel proved the intactness of the RNA samples. The average spectrophotometric values of the isolated RNA ranged from 1.96 to 2.02 ( A 260/280 ) and 1.95 to 2.14 ( A 260/230 ), indicating the high quality of RNA devoid of polyphenols, polysaccharides and protein contamination. In the optimized protocol, addition of PVPP to the extraction buffer and a brief incubation of samples at 65 °C and subsequent purification with potassium acetate resulted in good-quality RNA isolation. The suitability of RNA for downstream processing was confirmed by PCR amplification with cytochrome c oxidase gene-specific primers. The amplification of a single 392 bp fragment using cDNA and 1.5 kb fragment using genomic DNA samples confirmed the absence of DNA contamination. The present protocol is rapid and yielded good quality and quantity of RNA suitable for functional genomics studies.
Longmire, J.L.; Lewis, A.K.; Hildebrand, C.E.
1988-01-21
A method is provided for isolating DNA from eukaryotic cell and flow sorted chromosomes. When DNA is removed from chromosome and cell structure, detergent and proteolytic digestion products remain with the DNA. These products can be removed with organic extraction, but the process steps associated with organic extraction reduces the size of DNA fragments available for experimental use. The present process removes the waste products by dialyzing a solution containing the DNA against a solution containing polyethylene glycol (PEG). The waste products dialyze into the PEG leaving isolated DNA. The remaining DNA has been prepared with fragments containing more than 160 kb. The isolated DNA has been used in conventional protocols without effect on the protocol.
Diagnostic multiplex PCR for toxin genotyping of Clostridium perfringens isolates.
Baums, Christoph G; Schotte, Ulrich; Amtsberg, Gunter; Goethe, Ralph
2004-05-20
In this study we provide a protocol for genotyping Clostridium perfringens with a new multiplex PCR. This PCR enables reliable and specific detection of the toxin genes cpa, cpb, etx, iap, cpe and cpb2 from heat lysed bacterial suspensions. The efficiency of the protocol was demonstrated by typing C. perfringens reference strains and isolates from veterinary bacteriological routine diagnostic specimens.
Christou, Anastasis; Georgiadou, Egli C; Filippou, Panagiota; Manganaris, George A; Fotopoulos, Vasileios
2014-03-01
Strawberry plant tissues and particularly fruit material are rich in polysaccharides and polyphenolic compounds, thus rendering the isolation of nucleic acids a difficult task. This work describes the successful modification of a total RNA extraction protocol, which enables the isolation of high quantity and quality of total RNA from small amounts of strawberry leaf, root and fruit tissues. Reverse-transcription polymerase chain reaction (RT-PCR) amplification of GAPDH housekeeping gene from isolated RNA further supports the proposed protocol efficiency and its use for downstream molecular applications. This novel procedure was also successfully followed using other fruit tissues, such as olive and kiwifruit. In addition, optional treatment with RNase A following initial nucleic acid extraction can provide sufficient quality and quality of genomic DNA for subsequent PCR analyses, as evidenced from PCR amplification of housekeeping genes using extracted genomic DNA as template. Overall, this optimized protocol allows easy, rapid and economic isolation of high quality RNA from small amounts of an important fruit crop, such as strawberry, with extended applicability to other recalcitrant fruit crops. Copyright © 2013 Elsevier B.V. All rights reserved.
Isolation of integrin-based adhesion complexes.
Jones, Matthew C; Humphries, Jonathan D; Byron, Adam; Millon-Frémillon, Angélique; Robertson, Joseph; Paul, Nikki R; Ng, Daniel H J; Askari, Janet A; Humphries, Martin J
2015-03-02
The integration of cells with their extracellular environment is facilitated by cell surface adhesion receptors, such as integrins, which play important roles in both normal development and the onset of pathologies. Engagement of integrins with their ligands in the extracellular matrix, or counter-receptors on other cells, initiates the intracellular assembly of a wide variety of proteins into adhesion complexes such as focal contacts, focal adhesions, and fibrillar adhesions. The proteins recruited to these complexes mediate bidirectional signaling across the plasma membrane, and, as such, help to coordinate and/or modulate the multitude of physical and chemical signals to which the cell is subjected. The protocols in this unit describe two approaches for the isolation or enrichment of proteins contained within integrin-associated adhesion complexes, together with their local plasma membrane/cytosolic environments, from cells in culture. In the first protocol, integrin-associated adhesion structures are affinity isolated using microbeads coated with extracellular ligands or antibodies. The second protocol describes the isolation of ventral membrane preparations that are enriched for adhesion complex structures. The protocols permit the determination of adhesion complex components via subsequent downstream analysis by western blotting or mass spectrometry. Copyright © 2015 John Wiley & Sons, Inc.
Tessonnière, H; Vidal, S; Barnavon, L; Alexandre, H; Remize, F
2009-02-28
Because the yeast Brettanomyces produces volatile phenols and acetic acid, it is responsible for wine spoilage. The uncontrolled accumulation of these molecules in wine leads to sensorial defects that compromise wine quality. The need for a rapid, specific, sensitive and reliable method to detect this spoilage yeast has increased over the last decade. All these requirements are met by real-time PCR. We here propose improvements of existing methods to enhance the robustness of the assay. Six different protocols to isolate DNA from a wine and three PCR mix compositions were tested, and the best method was selected. Insoluble PVPP addition during DNA extraction by a classical phenol:chloroform protocol succeeded in the relief of PCR inhibitors from wine. We developed an internal control which was efficient to avoid false negative results due to decreases in the efficiency of DNA isolation and/or amplification. The method was evaluated by an intra-laboratory study for its specificity, linearity, repeatability and reproducibility. A standard curve was established from 14 different wines artificially inoculated. The quantification limit was 31 cfu/mL.
Comparative evaluation of three lignin isolation protocols for various wood species.
Guerra, Anderson; Filpponen, Ilari; Lucia, Lucian A; Argyropoulos, Dimitris S
2006-12-27
Milled wood lignin (MWL), cellulolytic enzyme lignin (CEL), and enzymatic mild acidolysis lignin (EMAL) were isolated from different wood species and characterized by various techniques. The EMAL protocol offered gravimetric lignin yields 2-5 times greater than those of the corresponding MWL and CEL. The purities of the EMALs were 3.75-10.6% higher than those of their corresponding CELs, depending upon the wood species from which they were isolated. Molecular weight analyses showed that the EMAL protocol isolates lignin fractions that are not accessed by the other procedures evaluated, while 31P NMR spectroscopy revealed that MWL is more condensed and bears more phenolic hydroxyl groups than EMAL and CEL. The yields and purities of EMAL, MWL, and CEL from hardwood were greater than those obtained for the examined softwoods. Structural details obtained by DFRC (derivatization followed by reductive cleavage)/31P NMR revealed different contents of condensed and uncondensed beta-O-aryl ether structures, dibenzodioxocins, and condensed and uncondensed phenolic hydroxyl and carboxylic acid groups within lignins isolated from different wood species.
General method for rapid purification of native chromatin fragments.
Kuznetsov, Vyacheslav I; Haws, Spencer A; Fox, Catherine A; Denu, John M
2018-05-24
Biochemical, proteomic and epigenetic studies of chromatin rely on the efficient ability to isolate native nucleosomes in high yield and purity. However, isolation of native chromatin suitable for many downstream experiments remains a challenging task. This is especially true for the budding yeast Saccharomyces cerevisiae, which continues to serve as an important model organism for the study of chromatin structure and function. Here, we developed a time- and cost-efficient universal protocol for isolation of native chromatin fragments from yeast, insect, and mammalian cells. The resulting protocol preserves histone posttranslational modification in the native chromatin state, and is applicable for both parallel multi-sample spin-column purification and large scale isolation. This protocol is based on the efficient and stable purification of polynucleosomes, features a combination of optimized cell lysis and purification conditions, three options for chromatin fragmentation, and a novel ion-exchange chromatographic purification strategy. The procedure will aid chromatin researchers interested in isolating native chromatin material for biochemical studies, and as a mild, acid- and detergent-free sample preparation method for mass-spectrometry analysis. Published under license by The American Society for Biochemistry and Molecular Biology, Inc.
Medina-Rodríguez, Eva María; Arenzana, Francisco Javier; Bribián, Ana; de Castro, Fernando
2013-01-01
During development, oligodendrocytes are generated from oligodendrocyte precursor cells (OPCs), a cell type that is a significant proportion of the total cells (3-8%) in the adult central nervous system (CNS) of both rodents and humans. Adult OPCs are responsible for the spontaneous remyelination that occurs in demyelinating diseases like Multiple Sclerosis (MS) and they constitute an interesting source of cells for regenerative therapy in such conditions. However, there is little data regarding the neurobiology of adult OPCs isolated from mice since an efficient method to isolate them has yet to be established. We have designed a protocol to obtain viable adult OPCs from the cerebral cortex of different mouse strains and we have compared its efficiency with other well-known methods. In addition, we show that this protocol is also useful to isolate functional OPCs from human brain biopsies. Using this method we can isolate primary cortical OPCs in sufficient quantities so as to be able to study their survival, maturation and function, and to facilitate an evaluation of their utility in myelin repair. PMID:24303061
Medina-Rodríguez, Eva María; Arenzana, Francisco Javier; Bribián, Ana; de Castro, Fernando
2013-01-01
During development, oligodendrocytes are generated from oligodendrocyte precursor cells (OPCs), a cell type that is a significant proportion of the total cells (3-8%) in the adult central nervous system (CNS) of both rodents and humans. Adult OPCs are responsible for the spontaneous remyelination that occurs in demyelinating diseases like Multiple Sclerosis (MS) and they constitute an interesting source of cells for regenerative therapy in such conditions. However, there is little data regarding the neurobiology of adult OPCs isolated from mice since an efficient method to isolate them has yet to be established. We have designed a protocol to obtain viable adult OPCs from the cerebral cortex of different mouse strains and we have compared its efficiency with other well-known methods. In addition, we show that this protocol is also useful to isolate functional OPCs from human brain biopsies. Using this method we can isolate primary cortical OPCs in sufficient quantities so as to be able to study their survival, maturation and function, and to facilitate an evaluation of their utility in myelin repair.
López-de-Uralde-Villanueva, Ibai; Candelas-Fernández, Pablo; de-Diego-Cano, Beatriz; Mínguez-Calzada, Orcález; Del Corral, Tamara
2018-06-01
The objective of this study was to evaluate whether the addition of manual therapy and therapeutic exercise protocol to inspiratory muscle training was more effective in improving maximum inspiratory pressure than inspiratory muscle training in isolation. This is a single-blinded, randomized controlled trial. In total, 43 patients with asthma were included in this study. The patients were allocated into one of the two groups: (1) inspiratory muscle training ( n = 21; 20-minute session) or (2) inspiratory muscle training (20-minute session) combined with a program of manual therapy (15-minute session) and therapeutic exercise (15-minute session; n = 22). All participants received 12 sessions, two days/week, for six weeks and performed the domiciliary exercises protocol. The main measures such as maximum inspiratory pressure, spirometric measures, forward head posture, and thoracic kyphosis were recorded at baseline and after the treatment. For the per-protocol analysis, between-group differences at post-intervention were observed in maximum inspiratory pressure (19.77 cmH 2 O (11.49-28.04), P < .05; F = 22.436; P < .001; η 2 p = 0.371) and forward head posture (-1.25 cm (-2.32 to -0.19), P < .05; F = 5.662; P = .022; η 2 p = 0.13). The intention-to-treat analysis showed the same pattern of findings. The inspiratory muscle training combined with a manual therapy and therapeutic exercise program is more effective than its application in isolation for producing short-term maximum inspiratory pressure and forward head posture improvements in patients with asthma.
Talundzic, Eldin; Chenet, Stella M.; Goldman, Ira F.; Patel, Dhruviben S.; Nelson, Julia A.; Plucinski, Mateusz M.; Barnwell, John W.; Udhayakumar, Venkatachalam
2015-01-01
Plasmodium falciparum resistance to artemisinin has emerged in the Greater Mekong Subregion and now poses a threat to malaria control and prevention. Recent work has identified mutations in the kelch propeller domain of the P. falciparum K13 gene to be associated artemisinin resistance as defined by delayed parasite clearance and ex vivo ring stage survival assays. Species specific primers for the two most prevalent human malaria species, P. falciparum and P. vivax, were designed and tested on multiple parasite isolates including human, rodent, and non- humans primate Plasmodium species. The new protocol described here using the species specific primers only amplified their respective species, P. falciparum and P. vivax, and did not cross react with any of the other human malaria Plasmodium species. We provide an improved species specific PCR and sequencing protocol that could be effectively used in areas where both P. falciparum and P. vivax are circulating. To design this improved protocol, the kelch gene was analyzed and compared among different species of Plasmodium. The kelch propeller domain was found to be highly conserved across the mammalian Plasmodium species. PMID:26292024
Talundzic, Eldin; Chenet, Stella M; Goldman, Ira F; Patel, Dhruviben S; Nelson, Julia A; Plucinski, Mateusz M; Barnwell, John W; Udhayakumar, Venkatachalam
2015-01-01
Plasmodium falciparum resistance to artemisinin has emerged in the Greater Mekong Subregion and now poses a threat to malaria control and prevention. Recent work has identified mutations in the kelch propeller domain of the P. falciparum K13 gene to be associated artemisinin resistance as defined by delayed parasite clearance and ex vivo ring stage survival assays. Species specific primers for the two most prevalent human malaria species, P. falciparum and P. vivax, were designed and tested on multiple parasite isolates including human, rodent, and non- humans primate Plasmodium species. The new protocol described here using the species specific primers only amplified their respective species, P. falciparum and P. vivax, and did not cross react with any of the other human malaria Plasmodium species. We provide an improved species specific PCR and sequencing protocol that could be effectively used in areas where both P. falciparum and P. vivax are circulating. To design this improved protocol, the kelch gene was analyzed and compared among different species of Plasmodium. The kelch propeller domain was found to be highly conserved across the mammalian Plasmodium species.
Efficient Isolation Protocol for B and T Lymphocytes from Human Palatine Tonsils
Assadian, Farzaneh; Sandström, Karl; Laurell, Göran; Svensson, Catharina; Akusjärvi, Göran; Punga, Tanel
2015-01-01
Tonsils form a part of the immune system providing the first line of defense against inhaled pathogens. Usually the term “tonsils” refers to the palatine tonsils situated at the lateral walls of the oral part of the pharynx. Surgically removed palatine tonsils provide a convenient accessible source of B and T lymphocytes to study the interplay between foreign pathogens and the host immune system. This video protocol describes the dissection and processing of surgically removed human palatine tonsils, followed by the isolation of the individual B and T cell populations from the same tissue sample. We present a method, which efficiently separates tonsillar B and T lymphocytes using an antibody-dependent affinity protocol. Further, we use the method to demonstrate that human adenovirus infects specifically the tonsillar T cell fraction. The established protocol is generally applicable to efficiently and rapidly isolate tonsillar B and T cell populations to study the role of different types of pathogens in tonsillar immune responses. PMID:26650582
Przekora, Agata; Zarnowski, Tomasz; Ginalska, Grazyna
2017-01-01
Human Tenon's fibroblasts (HTFs) play a crucial role in wound healing. They cause postoperative scarring of the filtering bleb and are thus responsible for trabeculectomy failure. This study aimed to find an effective and fast protocol for HTF isolation from trabeculectomy biopsies. The protocol was compared with the commonly recommended HTF isolation procedure, which uses Dulbecco's modified Eagle's medium (DMEM). We used Eagle's minimum essential medium (EMEM) enriched with fibroblast growth factor (FGF), which selectively promoted the proliferation of HTF cells. A secondary goal was to compare HTF morphology, metabolism and growth during parallel cultivation of the isolated cells in FGF-enriched EMEM and DMEM. Standard procedures for HTF isolation from tissue biopsies require a 20- to 30-day culture of the explants to obtain the first monolayer. Our protocol yielded the first monolayer after approx. 15 days. More importantly, the majority of the cells were fibroblasts with only individual epithelium-derived cells present. Using FGF-enriched EMEM allowed 1.3 × 10 6 vimentin-positive fibroblasts to be obtained from a single biopsy within approx. 25 days. Using DMEM resulted in isolation failure and required exchange to FGF-enriched medium to recover the fibroblast culture. HTFs maintained in FGF-enriched EMEM also showed faster proliferation and a different type I collagen production ability compared to HTFs cultured in DMEM. Thus, FGF-enriched EMEM is recommended for fast propagation of HTFs unless the aim of the study is to assess the effect of a tested agent on proliferation ability or type I collagen production. Our fast protocol for HTF isolation allows easy setup of cell banks by researchers under laboratory conditions and could be very useful during testing of novel ophthalmologic anti-fibrotic agents in vitro. Molecular analysis of HTFs isolated from patients with known treatment histories may provide valuable information on the effects of some medications taken before glaucoma surgery on the subsequent wound-healing process and potential for trabeculectomy failure.
Hardesty, Samantha L; Hagopian, Louis P; McIvor, Melissa M; Wagner, Leaora L; Sigurdsson, Sigurdur O; Bowman, Lynn G
2014-09-01
The present study isolated the effects of frequently used staff training intervention components to increase communication between direct care staff and clinicians working on an inpatient behavioral unit. Written "protocol review" quizzes developed by clinicians were designed to assess knowledge about a patient's behavioral protocols. Direct care staff completed these at the beginning of each day and evening shift. Clinicians were required to score and discuss these protocol reviews with direct care staff for at least 75% of shifts over a 2-week period. During baseline, only 21% of clinicians met this requirement. Completing and scoring of protocol reviews did not improve following additional in-service training (M = 15%) or following an intervention aimed at decreasing response effort combined with prompting (M = 28%). After implementing an intervention involving specified performance criterion and performance feedback, 86% of clinicians reached the established goal. Results of a component analysis suggested that the presentation of both the specified performance criterion and supporting contingencies was necessary to maintain acceptable levels of performance. © The Author(s) 2014.
Selective PEGylation of Parylene-C/SiO2 Substrates for Improved Astrocyte Cell Patterning.
Raos, B J; Doyle, C S; Simpson, M C; Graham, E S; Unsworth, C P
2018-02-09
Controlling the spatial distribution of glia and neurons in in vitro culture offers the opportunity to study how cellular interactions contribute to large scale network behaviour. A recently developed approach to cell-patterning uses differential adsorption of animal-serum protein on parylene-C and SiO 2 surfaces to enable patterning of neurons and glia. Serum, however, is typically poorly defined and generates reproducibility challenges. Alternative activation methods are highly desirable to enable patterning without relying on animal serum. We take advantage of the innate contrasting surface chemistries of parylene-C and SiO 2 to enable selective bonding of polyethylene glycol SiO 2 surfaces, i.e. PEGylation, rendering them almost completely repulsive to cell adhesion. As the reagents used in the PEGylation protocol are chemically defined, the reproducibility and batch-to-batch variability complications associated with the used of animal serum are avoided. We report that PEGylated parylene-C/SiO 2 substrates achieve a contrast in astrocyte density of 65:1 whereas the standard serum-immersion protocol results in a contrast of 5.6:1. Furthermore, single-cell isolation was significantly improved on PEGylated substrates when astrocytes were grown on close-proximity parylene-C nodes, whereas isolation was limited on serum-activated substrates due tolerance for cell adhesion on serum-adsorbed SiO 2 surfaces.
Link, K H; Kornmann, M; Leder, G; Pillasch, A F; Sunelaitis, E; Schatz, M; Pressmar, J; Beger, H G
1999-02-01
Since the developments in systemic chemotherapy of metastasized colorectal cancer have not resulted in substantial gains in survival times, we wished to improve the course of isolated nonresectable colorectal liver metastases (CPLM) by hepatic arterial infusion treatment. Patients (pts) with CRLM have a worse fate than those pts whose liver metastases could be resected. Systemic (i.v.) chemotherapy for CRLM/colorectal metastases does not improve survival to a relevant level (median survival time (med. surv.) after 5-Fluorouracil + Folinic Acid (5-FU + FA) i.v.: 6.4-14.3 months (m)). Hepatic artery infusion (HAI) with 5-Fluorode-oxyuridine (5-FUDR) has been demonstrated in a metaanalysis of randomized trials to be superior to i.v. treatment/palliative care (med. surv.: 15 vs. 10 m). The benefit of HAI with 5-FUDR, although recommended as treatment for CRLM, is severely compromised by the 5-FUDR induced hepatotoxicity, leading eventually to sclerosing cholangitis (SC)/liver scirrhosis. We have stepwise developed a protocol for HAI of CRLM, which is superior to HAI with 5-FUDR, and, most evidently, to systemic chemotherapy. Between 1982-1997, 222 CR (L) M patients were treated within subsequent protocols (Table). In protocol A, 68 CRLM pts received HAI with 5-FUDR (A1: nonrandomized pts; A2: randomized pts). In protocol B (randomized pts.), 46 pts received 5-FUDR i.a. (via HAI) + i.v. In protocol C, systemic chemotherapy with 5-FU + FA was conducted in 34 pts with metastasized colorectal cancers, including CRLM. In protocol D 5-FU + FA was delivered via HAI in 25 pts with CRLM. In protocol E, based on in vitro phase II studies and the results of protocol D, Mitoxantrone and Mitomycin C were added to 5-FU + FA (MFFM). Fifty (50) CRLM pts received HAI with MFFM. The response rates, med. surv. times, systemic toxicity and SC rates are shown in the table. HAI with MFFM produced objective responses in 66%, the med. surv. was 27.4 m, and no SC occurred. The ports surgically placed for HAI, e.g., in protocols D and E, functioned in 90%, 82%, and 76% 6, 9, and 11 m after start of the HAI. Quality of life in protocol E was high. Nine pts from protocols D + E with either partial (PR, 7 pts) or complete (CR, 2 pts) remissions received a secondary liver resection without hospital mortality, and 7/9 pts are living 2-58 m after liver resection, 2/9 pts died 11 and 22 m after resection. [table: see text] Our learning curve to achieve optimal treatment of CRLM resulted in a protocol using HAI with MFFM. The results of this protocol (E) including the high remission rate, long median survival time, good port function, high quality of life, and, most interestingly, the possibility to downstage and resect primarily nonresectable metastases, seem to be superior to HAI with 5-FUDR of 5-FU + FA and to systemic chemotherapy with 5-FU + FA. This hypothesis is currently examined in a phase III study (HAI with MFFM vs. 5-FU + FA i.v.).
Tan, K. E.; Ellis, B. C.; Lee, R.; Stamper, P. D.; Zhang, S. X.
2012-01-01
Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) has been found to be an accurate, rapid, and inexpensive method for the identification of bacteria and yeasts. Previous evaluations have compared the accuracy, time to identification, and costs of the MALDI-TOF MS method against standard identification systems or commercial panels. In this prospective study, we compared a protocol incorporating MALDI-TOF MS (MALDI protocol) with the current standard identification protocols (standard protocol) to determine the performance in actual practice using a specimen-based, bench-by-bench approach. The potential impact on time to identification (TTI) and costs had MALDI-TOF MS been the first-line identification method was quantitated. The MALDI protocol includes supplementary tests, notably for Streptococcus pneumoniae and Shigella, and indications for repeat MALDI-TOF MS attempts, often not measured in previous studies. A total of 952 isolates (824 bacterial isolates and 128 yeast isolates) recovered from 2,214 specimens were assessed using the MALDI protocol. Compared with standard protocols, the MALDI protocol provided identifications 1.45 days earlier on average (P < 0.001). In our laboratory, we anticipate that the incorporation of the MALDI protocol can reduce reagent and labor costs of identification by $102,424 or 56.9% within 12 months. The model included the fixed annual costs of the MALDI-TOF MS, such as the cost of protein standards and instrument maintenance, and the annual prevalence of organisms encountered in our laboratory. This comprehensive cost analysis model can be generalized to other moderate- to high-volume laboratories. PMID:22855510
Tan, K E; Ellis, B C; Lee, R; Stamper, P D; Zhang, S X; Carroll, K C
2012-10-01
Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has been found to be an accurate, rapid, and inexpensive method for the identification of bacteria and yeasts. Previous evaluations have compared the accuracy, time to identification, and costs of the MALDI-TOF MS method against standard identification systems or commercial panels. In this prospective study, we compared a protocol incorporating MALDI-TOF MS (MALDI protocol) with the current standard identification protocols (standard protocol) to determine the performance in actual practice using a specimen-based, bench-by-bench approach. The potential impact on time to identification (TTI) and costs had MALDI-TOF MS been the first-line identification method was quantitated. The MALDI protocol includes supplementary tests, notably for Streptococcus pneumoniae and Shigella, and indications for repeat MALDI-TOF MS attempts, often not measured in previous studies. A total of 952 isolates (824 bacterial isolates and 128 yeast isolates) recovered from 2,214 specimens were assessed using the MALDI protocol. Compared with standard protocols, the MALDI protocol provided identifications 1.45 days earlier on average (P < 0.001). In our laboratory, we anticipate that the incorporation of the MALDI protocol can reduce reagent and labor costs of identification by $102,424 or 56.9% within 12 months. The model included the fixed annual costs of the MALDI-TOF MS, such as the cost of protein standards and instrument maintenance, and the annual prevalence of organisms encountered in our laboratory. This comprehensive cost analysis model can be generalized to other moderate- to high-volume laboratories.
Nucleic acid isolation process
Longmire, Jonathan L.; Lewis, Annette K.; Hildebrand, Carl E.
1990-01-01
A method is provided for isolating DNA from eukaryotic cell and flow sorted chromosomes. When DNA is removed from chromosome and cell structure, detergent and proteolytic digestion products remain with the DNA. These products can be removed with organic extraction, but the process steps associated with organic extraction reduce the size of DNA fragments available for experimental use. The present process removes the waste products by dialyzing a solution containing the DNA against a solution containing polyethylene glycol (PEG). The waste products dialyze into the PEG leaving isolated DNA. The remaining DNA has been prepared with fragments containing more than 160 kb. The isolated DNA has been used in conventional protocols without affect on the protocol.
Koetsveld, J; Kolyasnikova, N M; Wagemakers, A; Toporkova, M G; Sarksyan, D S; Oei, A; Platonov, A E; Hovius, J W
2017-07-01
Borrelia miyamotoi has been shown to infect humans in Eurasia and North America causing hard tick-borne relapsing fever (HTBRF). In vitro cultivation of B. miyamotoi was described recently; but clinical isolation of relapsing fever Borrelia is cumbersome. Our aim was to develop a straightforward protocol enabling B. miyamotoi isolation directly from the blood of patients. Modified Kelly-Pettenkorfer (MKP-F) medium, with or without anticoagulants, or blood from healthy human volunteers, was spiked with B. miyamotoi spirochaetes in vitro. Subsequently, either media or plasma was used for cultivation directly, or after an additional centrifugation step. This isolation protocol was tested in a clinical setting on patients suspected of HTBRF. Dipotassium-EDTA, trisodium citrate and lithium heparin inhibited growth of B. miyamotoi at concentrations ≥250 μg/mL, 2.5 mM and 1 IU/mL, respectively. However, when plasma originating from human blood containing B. miyamotoi spirochaetes was subjected to an additional centrifugation step at 8000 g, suspended and inoculated into fresh MKP-F media, positive cultures were observed within 2 weeks. Of importance, this straightforward protocol allowed for isolation of B. miyamotoi from six out of nine patients with confirmed HTBRF. Direct culture from K 2 -EDTA, trisodium citrate and lithium heparin plasma containing B. miyamotoi is hampered due to anticoagulants. Using a simple centrifugation protocol we were able to circumvent this detrimental effect, allowing for the first clinical isolation of B. miyamotoi. This will be of value for future research on the pathogenesis, genetics, diagnosis, therapy and epidemiology of HTBRF and other tick-borne relapsing fevers. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.
Quality and Variability of Online Physical Therapy Protocols for Isolated Meniscal Repairs.
Trofa, David P; Parisien, Robert L; Noticewala, Manish S; Noback, Peter C; Ahmad, Christopher S; Moutzouros, Vasilios; Makhni, Eric C
2018-05-31
The ideal meniscal repair postoperative rehabilitation protocol has yet to be determined. Further, patients are attempting to access health care content online at a precipitously increasing rate given the efficiency of modern search engines. The purpose of this investigation was to assess the quality and variability of meniscal repair rehabilitation protocols published online with the hypothesis that there would be a high degree of variability found across available protocols. To this end, Web-based meniscal repair physical therapy protocols from U.S. academic orthopaedic programs as well as the first 10 protocols identified by the Google search engine for the term "meniscal repair physical therapy protocol" were reviewed and assessed via a custom scoring rubric. Twenty protocols were identified from 155 U.S. academic orthopaedic programs for a total of 30 protocols. Twenty-six protocols (86.6%) recommended immediate postoperative bracing. Twelve (40.0%) protocols permitted immediate weight-bearing as tolerated (WBAT) postoperatively, while the remaining protocols permitted WBAT at an average of 4.0 (range, 1-7) weeks. There was considerable variation in range of motion (ROM) goals, with most protocols (73.3%) initiating immediate passive ROM to 90°. The types and timing of strength, proprioception, agility, and pivoting exercises advised were extremely diverse. Only five protocols (16.7%) employed functional testing as a marker for return to athletics. The results of this study indicate that only a minority of academic orthopaedic programs publish meniscal repair physical therapy protocols online and that within the most readily available online protocols there are significant disparities in regards to brace use, ROM, weight-bearing, and strengthening and proprioception exercises. These discrepancies reflect the fact that the best rehabilitation practices after a meniscal repair have yet to be elucidated. This represents a significant area for improved patient care through standardization. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
Resource sharing on CSMA/CD networks in the presence of noise. M.S. Thesis
NASA Technical Reports Server (NTRS)
Dinschel, Duane Edward
1987-01-01
Resource sharing on carrier sense multiple access with collision detection (CSMA/CD) networks can be accomplished by using window-control algorithms for bus contention. The window-control algorithms are designed to grant permission to transmit to the station with the minimum contention parameter. Proper operation of the window-control algorithm requires that all stations sense the same state of the newtork in each contention slot. Noise causes the state of the network to appear as a collision. False collisions can cause the window-control algorithm to terminate without isolating any stations. A two-phase window-control protocol and approximate recurrence equation with noise as a parameter to improve the performance of the window-control algorithms in the presence of noise are developed. The results are compared through simulation, with the approximate recurrence equation yielding the best overall performance. Noise is even a bigger problem when it is not detected by all stations. In such cases it is possible for the window boundaries of the contending stations to become out of phase. Consequently, it is possible to isolate a station other than the one with the minimum contention parameter. To guarantee proper isolation of the minimum, a broadcast phase must be added after the termination of the algorithm. The protocol required to correct the window-control algorithm when noise is not detected by all stations is discussed.
Primary Culture System for Germ Cells from Caenorhabditis elegans Tumorous Germline Mutants
Vagasi, Alexandra S.; Rahman, Mohammad M.; Chaudhari, Snehal N.; Kipreos, Edward T.
2017-01-01
The Caenorhabditis elegans germ line is an important model system for the study of germ stem cells. Wild-type C. elegans germ cells are syncytial and therefore cannot be isolated in in vitro cultures. In contrast, the germ cells from tumorous mutants can be fully cellularized and isolated intact from the mutant animals. Here we describe a detailed protocol for the isolation of germ cells from tumorous mutants that allows the germ cells to be maintained for extended periods in an in vitro primary culture. This protocol has been adapted from Chaudhari et al., 2016. PMID:28868332
Liver plasma membranes: an effective method to analyze membrane proteome.
Cao, Rui; Liang, Songping
2012-01-01
Plasma membrane proteins are critical for the maintenance of biological systems and represent important targets for the treatment of disease. The hydrophobicity and low abundance of plasma membrane proteins make them difficult to analyze. The protocols given here are the efficient isolation/digestion procedures for liver plasma membrane proteomic analysis. Both protocol for the isolation of plasma membranes and protocol for the in-gel digestion of gel-embedded plasma membrane proteins are presented. The later method allows the use of a high detergent concentration to achieve efficient solubilization of hydrophobic plasma membrane proteins while avoiding interference with the subsequent LC-MS/MS analysis.
Yazdekhasti, Hossein; Rajabi, Zahra; Parvari, Soraya; Abbasi, Mehdi
2016-10-20
Although existence of ovarian stem cells (OSCs) in mammalian postnatal ovary is still under controversy, however, it has been almost accepted that OSCs are contributing actively to folliculogenesis and neo-oogenesis. Recently, various methods with different efficacies have been employed for OSCs isolation from ovarian tissue, which these methods could be chosen depends on aim of isolation and accessible equipments and materials in lab. Although isolated OSCs from different methods have various traits and characterizations, which might become from their different nature and origin, however these stem cells are promising source for woman infertility treatment or source of energy for women with a history of repeat IVF failure in near future. This review has brought together and summarized currently used protocols for isolation and propagation of OSCs in vitro.
Expansion and cryopreservation of porcine and human corneal endothelial cells.
Marquez-Curtis, Leah A; McGann, Locksley E; Elliott, Janet A W
2017-08-01
Impairment of the corneal endothelium causes blindness that afflicts millions worldwide and constitutes the most often cited indication for corneal transplants. The scarcity of donor corneas has prompted the alternative use of tissue-engineered grafts which requires the ex vivo expansion and cryopreservation of corneal endothelial cells. The aims of this study are to culture and identify the conditions that will yield viable and functional corneal endothelial cells after cryopreservation. Previously, using human umbilical vein endothelial cells (HUVECs), we employed a systematic approach to optimize the post-thaw recovery of cells with high membrane integrity and functionality. Here, we investigated whether improved protocols for HUVECs translate to the cryopreservation of corneal endothelial cells, despite the differences in function and embryonic origin of these cell types. First, we isolated endothelial cells from pig corneas and then applied an interrupted slow cooling protocol in the presence of dimethyl sulfoxide (Me 2 SO), with or without hydroxyethyl starch (HES). Next, we isolated and expanded endothelial cells from human corneas and applied the best protocol verified using porcine cells. We found that slow cooling at 1 °C/min in the presence of 5% Me 2 SO and 6% HES, followed by rapid thawing after liquid nitrogen storage, yields membrane-intact cells that could form monolayers expressing the tight junction marker ZO-1 and cytoskeleton F-actin, and could form tubes in reconstituted basement membrane matrix. Thus, we show that a cryopreservation protocol optimized for HUVECs can be applied successfully to corneal endothelial cells, and this could provide a means to address the need for off-the-shelf cryopreserved cells for corneal tissue engineering and regenerative medicine. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
Tailor, Vijay; Glaze, Selina; Unwin, Hilary; Bowman, Richard; Thompson, Graham; Dahlmann-Noor, Annegret
2016-10-01
Children and adults with neurological impairments are often not able to access conventional perimetry; however, information about the visual field is valuable. A new technology, saccadic vector optokinetic perimetry (SVOP), may have improved accessibility, but its accuracy has not been evaluated. We aimed to explore accessibility, testability and accuracy of SVOP in children with neurodisability or isolated visual pathway deficits. Cohort study; recruitment October 2013-May 2014, at children's eye clinics at a tertiary referral centre and a regional Child Development Centre; full orthoptic assessment, SVOP (central 30° of the visual field) and confrontation visual fields (CVF). Group 1: age 1-16 years, neurodisability (n=16), group 2: age 10-16 years, confirmed or suspected visual field defect (n=21); group 2 also completed Goldmann visual field testing (GVFT). Group 1: testability with a full 40-point test protocol is 12.5%; with reduced test protocols, testability is 100%, but plots may be clinically meaningless. Children (44%) and parents/carers (62.5%) find the test easy. SVOP and CVF agree in 50%. Group 2: testability is 62% for the 40-point protocol, and 90.5% for reduced protocols. Corneal changes in childhood glaucoma interfere with SVOP testing. All children and parents/carers find SVOP easy. Overall agreement with GVFT is 64.7%. While SVOP is highly accessible to children, many cannot complete a full 40-point test. Agreement with current standard tests is moderate to poor. Abnormal saccades cause an apparent non-specific visual field defect. In children with glaucoma or nystagmus SVOP calibration often fails. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Japour, A J; Mayers, D L; Johnson, V A; Kuritzkes, D R; Beckett, L A; Arduino, J M; Lane, J; Black, R J; Reichelderfer, P S; D'Aquila, R T
1993-01-01
A standardized antiviral drug susceptibility assay for clinical human immunodeficiency virus type 1 (HIV-1) isolates has been developed for use in clinical trials. The protocol is a two-step procedure that first involves cocultivation of patient infected peripheral blood mononuclear cells (PBMC) with seronegative phytohemagglutinin-stimulated donor PBMC to obtain an HIV-1 stock. The virus stock is titrated for viral infectivity (50% tissue culture infective dose) by use of serial fourfold virus dilutions in donor PBMC. A standardized inoculum of 1,000 50% tissue culture infective doses per 10(6) cells is used in the second step of the procedure to acutely infect seronegative donor PBMC in a 7-day microtiter plate assay with triplicate wells containing zidovudine (ZDV) concentrations ranging from 0 to 5.0 microM. The ZDV 50% inhibitory concentrations (IC50) for reference ZDV-susceptible and ZDV-resistant HIV-1 isolates ranged from 0.002 to 0.113 microM and from 0.15 to > 5.0 microM, respectively. Use of this consensus protocol reduced interlaboratory variability for ZDV IC50 determinations with reference HIV-1 isolates. Among eight laboratories, the coefficient of variation ranged from 0.85 to 1.25 with different PBMC protocols and was reduced to 0.39 to 0.98 with the standardized assay. Among the clinical HIV-1 isolates assayed by the standardized drug susceptibility assay, the median ZDV IC50 increased gradually with more ZDV therapy. This protocol provides an efficient and reproducible means to assess the in vitro susceptibility to antiretroviral agents of virtually all clinical HIV-1 isolates. PMID:8517697
Laget, Sophie; Dhingra, Dalia M.; BenMohamed, Fatima; Capiod, Thierry; Osteras, Magne; Farinelli, Laurent; Jackson, Stephen; Paterlini-Bréchot, Patrizia
2017-01-01
Circulating Tumor Cells (CTC) and Circulating Tumor Microemboli (CTM) are Circulating Rare Cells (CRC) which herald tumor invasion and are expected to provide an opportunity to improve the management of cancer patients. An unsolved technical issue in the CTC field is how to obtain highly sensitive and unbiased collection of these fragile and heterogeneous cells, in both live and fixed form, for their molecular study when they are extremely rare, particularly at the beginning of the invasion process. We report on a new protocol to enrich from blood live CTC using ISET® (Isolation by SizE of Tumor/Trophoblastic Cells), an open system originally developed for marker-independent isolation of fixed tumor cells. We have assessed the impact of our new enrichment method on live tumor cells antigen expression, cytoskeleton structure, cell viability and ability to expand in culture. We have also explored the ISET® in vitro performance to collect intact fixed and live cancer cells by using spiking analyses with extremely low number of fluorescent cultured cells. We describe results consistently showing the feasibility of isolating fixed and live tumor cells with a Lower Limit of Detection (LLOD) of one cancer cell per 10 mL of blood and a sensitivity at LLOD ranging from 83 to 100%. This very high sensitivity threshold can be maintained when plasma is collected before tumor cells isolation. Finally, we have performed a comparative next generation sequencing (NGS) analysis of tumor cells before and after isolation from blood and culture. We established the feasibility of NGS analysis of single live and fixed tumor cells enriched from blood by our system. This study provides new protocols for detection and characterization of CTC collected from blood at the very early steps of tumor invasion. PMID:28060956
A Method of Porcine Pancreatic Islet Isolation for Microencapsulation.
Kendall, William F; Opara, Emmanuel C
2017-01-01
Since the discovery of insulin by Banting and Best in 1921, the prognosis and treatment options for individuals with diabetes have improved. The development of various insulin types, various oral agents, and insulin pumps have improved the available medical options for individuals afflicted with diabetes. The current need for frequent blood glucose monitoring imposed by multiple daily insulin injections, result in significant life-style challenges for in individuals afflicted with Type 1 diabetes (T1D). In contrast the use of surgical interventions, such as whole organ pancreas transplantation (PT) requires less-intensive glucose monitoring while the organ is viable. Also, isolated human pancreatic islet transplantation (IT) holds similar promise as PT; however, the limited availability of human pancreata exacerbated by, the need for multiple pancreata per individual IT recipient, and issues with prolonged viability, still hamper widespread successful, and routine use of IT. The use of porcine pancreata holds promise as a viable alternative to human pancreas to significantly increase the volume of islets available to meet the needs of millions of patients afflicted with T1D. This chapter outlines our protocol utilized to reliably isolate and microencapsulate porcine islets.
Dulugiac, Magda; Moldovan, Lucia; Zarnescu, Otilia
2015-10-01
We have identified some critical aspects concerning umbilical cord tissue mesenchymal stem cells: the lack of standards for cell isolation, expansion and cryopreservation, the lack of unanimous opinions upon their multilineage differentiation potential and the existence of very few results related to the functional characterization of the cells isolated from cryopreserved umbilical cord tissue. Umbilical cord tissue cryopreservation appears to be the optimal solution for umbilical cord tissue mesenchymal stem cells storage for future clinical use. Umbilical cord tissue cryopreservation allows mesenchymal stem cells isolation before expected use, according with the specific clinical applications, by different customized isolation and expansion protocols agreed by cell therapy institutions. Using an optimized protocol for umbilical cord tissue cryopreservation in autologous cord blood plasma, isolation explant method and growth media supplemented with FBS or human serum, we performed comparative studies with respect to the characteristics of mesenchymal stem cells (MSC) isolated from different compartments of the same umbilical cord tissue such as Wharton's jelly, vein, arteries, before cryopreservation (pre freeze) and after cryopreservation (post thaw). Expression of histochemical and immunohistochemical markers as well as electron microscopy observations revealed similar adipogenic, chondrogenic and osteogenic differentiation capacity for cells isolated from pre freeze and corresponding post thaw tissue fragments of Wharton's jelly, vein or arteries of the same umbilical cord tissue, regardless growth media used for cells isolation and expansion. Our efficient umbilical cord tissue cryopreservation protocol is reliable for clinical applicability of mesenchymal stem cells that could next be isolated and expanded in compliance with future accepted standards. Copyright © 2015 Elsevier Ltd. All rights reserved.
Schneider, Stefan; Abeln, Vera; Popova, Julia; Fomina, Elena; Jacubowski, Amrei; Meeusen, Romain; Strüder, Heiko K
2013-01-01
With respect to the plans of national and internationals space agencies to send people to Mars or Moon, long-term isolation studies are performed to learn about the psycho-physiological and psycho-social limitations of such missions. From June 3rd 2010 to November 4th 2011 six participants lived under totally isolated and confined conditions in the MARS500 habitat located in Moscow. Despite the possibility to mimic the condition of space travel, this study allowed for experimental conditions under very reliable and traceable conditions. As exercise is widely discussed to have a positive impact on neuro-cognitive performance, this study aimed to test the effect of different exercise protocol (endurance/strength orientated) on brain cortical activity and cognitive performance. Brain cortical activity was recorded using a 16 channel EEG before and after exercise across the 520 days of confinement. Cognitive performance was assessed using three commercially available brain games. Following the theory of transient hypofrontality, results show a significant decrease of frontal brain cortical activity after exercise (p<.05) which was most expressed after endurance orientated protocols. Cognitive performance was improved following running sessions on an active treadmill (p<.05). Results let us assume that not exercise per se acts as a neuro-enhancer. It is more likely that a general defocusing caused by an immersion into exercise is necessary to improve cognitive performance. Copyright © 2012 Elsevier B.V. All rights reserved.
Avanesyan, Alina; Jaffe, Benjamin D.; Guédot, Christelle
2017-01-01
The spotted wing drosophila, Drosophila suzukii (Diptera: Drosophilidae), is an emerging invasive pest, which attacks a wide variety of fruits and berries. Although previous studies have focused on different aspects of D. suzukii reproductive biology, there are no protocols available for determining the mating status of D. suzukii females and drosophilids in general. In this study, a step-by-step protocol for tissue dissection, isolating spermathecae, and determining the mating status of females was developed specifically for D. suzukii. This protocol is an effective and relatively quick method for determining female mating status. It has important applications from exploring reproductive output of D. suzukii females to understanding the biology of D. suzukii winter morph, which presumably plays the main role in the overwintering of this invasive species. We demonstrated applicability of this protocol for both field collected flies and flies reared in the lab, including fly specimens stored on a long-term basis. PMID:28287438
Iliescu, D; Tudorache, S; Comanescu, A; Antsaklis, P; Cotarcea, S; Novac, L; Cernea, N; Antsaklis, A
2013-09-01
To assess the potential of first-trimester sonography in the detection of fetal abnormalities using an extended protocol that is achievable with reasonable resources of time, personnel and ultrasound equipment. This was a prospective two-center 2-year study of 5472 consecutive unselected pregnant women examined at 12 to 13 + 6 gestational weeks. Women were examined using an extended morphogenetic ultrasound protocol that, in addition to the basic evaluation, involved a color Doppler cardiac sweep and identification of early contingent markers for major abnormalities. The prevalence of lethal and severe malformations was 1.39%. The first-trimester scan identified 40.6% of the cases detected overall and 76.3% of major structural defects. The first-trimester detection rate (DR) for major congenital heart disease (either isolated or associated with extracardiac abnormalities) was 90% and that for major central nervous system anomalies was 69.5%. In fetuses with increased nuchal translucency (NT), the first-trimester DR for major anomalies was 96%, and in fetuses with normal NT it was 66.7%. Most (67.1%) cases with major abnormalities presented with normal NT. A detailed first-trimester anomaly scan using an extended protocol is an efficient screening method to detect major fetal structural abnormalities in low-risk pregnancies. It is feasible at 12 to 13 + 6 weeks with ultrasound equipment and personnel already used for routine first-trimester screening. Rate of detection of severe malformations is greater in early- than in mid-pregnancy and on postnatal evaluation. Early heart investigation could be improved by an extended protocol involving use of color Doppler. Copyright © 2013 ISUOG. Published by John Wiley & Sons Ltd.
Ritter, Katrina G; Hussey, Matthew J; Valovich McLeod, Tamara C
2017-09-27
Clinical Scenario: Patients who experience prolonged concussion symptoms can be diagnosed with Post-Concussion Syndrome (PCS) when those symptoms persist past 4 weeks. Aerobic exercise protocols have been shown to be effective in improving physical and mental aspects of health. Emerging research suggests that aerobic exercise maybe useful as a treatment for PCS, where exercise allows patients to feel less isolated and more active during the recovery process. Is aerobic exercise more beneficial in reducing symptoms than current standard care in patients with prolonged symptoms or PCS lasting longer than 4 weeks? Summary of Key Findings: After a thorough literature search, 4 studies were selected relevant to the clinical question. Of the 4 studies, 1 was a randomized control trial and 3 were case series. All 4 studies investigate aerobic exercise protocol as treatment for PCS. 1-4 Three articles demonstrated a greater rate of symptom improvement from baseline assessment to follow-up after a controlled sub-symptomatic aerobic exercise program. 2-4 One study showed a decrease in symptoms in the aerobic exercise group compared to the full body stretching group. 1 Clinical Bottom Line: There is moderate evidence to support sub-symptomatic aerobic exercise as a treatment of PCS, therefore it should be considered as a clinical option for reducing PCS and prolonged concussion symptoms. A previously validated protocol, such as the Buffalo Concussion Treadmill Test, Balke Protocol, or Rating of Perceived Exertion (RPE) as mentioned in this critically appraised topic should be used to measure baseline values and treatment progression. Strength of Recommendation: Level C evidence exists that aerobic exercise protocol is more effective than the current standard of care in treating PCS.
Norman, I D; Aikins, M; Binka, F N
2011-12-01
Hospitals and other health facilities in Ghana do not appear to have standardized practices for quarantine and isolation in public health emergency management. This paper reviews the legislative framework governing the medico-legal prerequisites for initiating quarantine and isolation procedures as articulated in the Infectious Disease Act (Cap 78) 1908 amended, 1935, the Quarantine Act (Cap 77) 1915 amended, 1938, the Emergency Powers Act of 1994, (Act 472), and the National Disaster Management Act, 1996, (Act 517) in consonance with the 1992 Constitution of Ghana. The findings provide that (1) The legislative framework outlines systematic standards and protocols to be followed in the committal of person or persons in quarantine and isolation during public health emergencies. (2) These standards and protocols consider as imperative, the creation of standardized national templates for the initiation of quarantine and isolation measures. (3) The non-compliance of the standards and protocols renders vulnerable medical facilities and hospitals with their personnel to the threat of medical malpractice suits and breach of professional ethics. This paper provides suggestions to hospital administrators and medical personnel of how to develop administrative templates in compliance with the law in managing public health emergencies. It also provides examples of such templates for possible adoption by hospitals and other health administrators.
Clinical impact of reducing routine blood culture incubation time from 7 to 5 days.
Marginson, Michael J; Daveson, Kathryn L; Kennedy, Karina J
2014-12-01
The aim of this study was to determine the clinical impact of reducing the blood culture incubation protocol from 7 to 5 days.A laboratory data extraction identified positive blood cultures occurring after 5 or more days of incubation at Canberra Hospital, Australia between 1 January 2001 and 31 August 2011. Isolates were identified as clinically significant using a pre-existing prospective bacteraemia database. Medical records review determined whether the positive result affected clinical management.Positive blood cultures after 5 or more days of incubation accounted for 2.65% (423/15979) of all positive blood cultures, although the majority were false positives or contaminants. Eighty-five were significant/indeterminate, representing an average of eight cases per year or 0.47% (85/15979) of all positive blood cultures sets. Forty-three were isolated for the first time, representing 1.1% of all significant/indeterminate blood culture episodes. Fungi and anaerobic bacteria compromised over 50% of isolates. In 26 cases (2.4 cases per year), the culture result led to a change in patient management.A 7 day incubation protocol is preferable due to late isolation of organisms; however, if space is required to accommodate increasing blood culture numbers, reducing to a 5 or 6 day protocol would miss only a small percentage of clinically significant isolates.
Lemaire, Clementine A; Liu, Sean Z; Wilkerson, Charles L; Ramani, Vishnu C; Barzanian, Nasim A; Huang, Kuo-Wei; Che, James; Chiu, Michael W; Vuppalapaty, Meghah; Dimmick, Adam M; Carlo, Dino Di; Kochersperger, Michael L; Crouse, Steve C; Jeffrey, Stefanie S; Englert, Robert F; Hengstler, Stephan; Renier, Corinne; Sollier-Christen, Elodie
2018-02-01
Tumor tissue biopsies are invasive, costly, and collect a limited cell population not completely reflective of patient cancer cell diversity. Circulating tumor cells (CTCs) can be isolated from a simple blood draw and may be representative of the diverse biology from multiple tumor sites. The VTX-1 Liquid Biopsy System was designed to automate the isolation of clinically relevant CTC populations, making the CTCs available for easy analysis. We present here the transition from a cutting-edge microfluidic innovation in the lab to a commercial, automated system for isolating CTCs directly from whole blood. As the technology evolved into a commercial system, flexible polydimethylsiloxane microfluidic chips were replaced by rigid poly(methyl methacrylate) chips for a 2.2-fold increase in cell recovery. Automating the fluidic processing with the VTX-1 further improved cancer cell recovery by nearly 1.4-fold, with a 2.8-fold decrease in contaminating white blood cells and overall improved reproducibility. Two isolation protocols were optimized that favor either the cancer cell recovery (up to 71.6% recovery) or sample purity (≤100 white blood cells/mL). The VTX-1's performance was further tested with three different spiked breast or lung cancer cell lines, with 69.0% to 79.5% cell recovery. Finally, several cancer research applications are presented using the commercial VTX-1 system.
Current Status of Islet Cell Transplantation
Ichii, Hirohito; Ricordi, Camillo
2013-01-01
Despite substantial advances in islet isolation methods and immunosuppressive protocol, pancreatic islet cell transplantation remains an experimental procedure currently limited to the most severe cases of type 1 diabetes mellitus (T1DM). The objectives of this treatment are to prevent severe hypoglycemic episodes in patients with hypoglycemia unawareness, and to achieve a more physiological metabolic control. Insulin independence and long term-graft function with improvement of quality of life have been obtained in several international islet transplant centers. However, experimental trials of islet transplantation clearly highlighted several obstacles that remain to be overcome before the procedure could be proposed to a much larger patient population. This review provides a brief historical perspective of islet transplantation, islet isolation techniques, the transplant procedure, immunosuppressive therapy, and outlines current challenges and future directions in clinical islet transplantation. PMID:19110649
Comparison of protocols measuring diffusion and partition coefficients in the stratum corneum
Rothe, H.; Obringer, C.; Manwaring, J.; Avci, C.; Wargniez, W.; Eilstein, J.; Hewitt, N.; Cubberley, R.; Duplan, H.; Lange, D.; Jacques‐Jamin, C.; Klaric, M.; Schepky, A.
2017-01-01
Abstract Partition (K) and diffusion (D) coefficients are important to measure for the modelling of skin penetration of chemicals through the stratum corneum (SC). We compared the feasibility of three protocols for the testing of 50 chemicals in our main studies, using three cosmetics‐relevant model chemicals with a wide range of logP values. Protocol 1: SC concentration‐depth profile using tape‐stripping (measures KSC/v and DSC/HSC 2, where HSC is the SC thickness); Protocol 2A: incubation of isolated SC with chemical (direct measurement of KSC/v only) and Protocol 2B: diffusion through isolated SC mounted on a Franz cell (measures KSC/v and DSC/HSC 2, and is based on Fick's laws). KSC/v values for caffeine and resorcinol using Protocol 1 and 2B were within 30% of each other, values using Protocol 2A were ~two‐fold higher, and all values were within 10‐fold of each other. Only indirect determination of KSC/v by Protocol 2B was different from the direct measurement of KSC/v by Protocol 2A and Protocol 1 for 7‐EC. The variability of KSC/v for all three chemicals using Protocol 2B was higher compared to Protocol 1 and 2A. DSC/HSC 2 values for the three chemicals were of the same order of magnitude using all three protocols. Additionally, using Protocol 1, there was very little difference between parameters measured in pig and human SC. In conclusion, KSC/v, and DSC values were comparable using different methods. Pig skin might be a good surrogate for human skin for the three chemicals tested. Copyright © 2017 The Authors Journal of Applied Toxicology published by John Wiley & Sons Ltd. PMID:28139006
A new rapid method for isolating nucleoli.
Li, Zhou Fang; Lam, Yun Wah
2015-01-01
The nucleolus was one of the first subcellular organelles to be isolated from the cell. The advent of modern proteomic techniques has resulted in the identification of thousands of proteins in this organelle, and live cell imaging technology has allowed the study of the dynamics of these proteins. However, the limitations of current nucleolar isolation methods hinder the further exploration of this structure. In particular, these methods require the use of a large number of cells and tedious procedures. In this chapter we describe a new and improved nucleolar isolation method for cultured adherent cells. In this method cells are snap-frozen before direct sonication and centrifugation onto a sucrose cushion. The nucleoli can be obtained within a time as short as 20 min, and the high yield allows the use of less starting material. As a result, this method can capture rapid biochemical changes in nucleoli by freezing the cells at a precise time, hence faithfully reflecting the protein composition of nucleoli at the specified time point. This protocol will be useful for proteomic studies of dynamic events in the nucleolus and for better understanding of the biology of mammalian cells.
Prendergast, Deirdre M; Hand, Darren; Nί Ghallchóir, Eadaoin; McCabe, Evonne; Fanning, Seamus; Griffin, Margaret; Egan, John; Gutierrez, Montserrat
2013-08-16
Salmonella enterica subsp. enterica serovar 4,[5],12:i:- is considered to be a monophasic variant of Salmonella Typhimurium and is increasingly associated with human infections. The use of PCR for the unequivocal identification of strains identified by conventional serotyping as 4,[5],12:i:- has been recommended by the European Food Safety Authority (EFSA), in particular the conventional multiplex PCR developed by Tennant et al. (2010). An alternative protocol for the identification and differentiation of S. Typhimurium and S. Typhimurium-like strains, including its monophasic variants, based on a multiplex real-time PCR assay was developed in our laboratory. A panel of 206 Salmonella strains was used to validate our multiplex real-time PCR against the conventional multiplex PCR recommended by EFSA, i.e. 43 Salmonella strains of serovars other than Typhimurium and 163 routine isolates determined by slide agglutination serotyping to have an incomplete antigenic formula compatible with the S. Typhimurium formula 4,[5],12:i:1,2. Both methods correctly identified the 43 Salmonella strains as non S. Typhimurium. Among the 163 isolates of undetermined serovar by conventional serotyping, both PCR protocols identified 54 isolates as S. Typhimurium, 101 as monophasic S. Typhimurium and 8 as non-S. Typhimurium. Twenty isolates phenotypically lacking the phase-2 H antigen were positive for the fljB.1,2 gene. These strains have been recently described in the literature by other workers and have been referred to as "inconsistent" variants of S. Typhimurium. Antimicrobial resistance and phage typing were also performed on the S. Typhimurium isolates, including monophasic variants, and approximately half of the isolates identified as monophasic S. Typhimurium by our multiplex real-time PCR protocol were DT193 with the resistance pattern ASSuT. There was 100% concordance between the conventional PCR and the multiplex real-time PCR method developed in this study which proved that our protocol is equivalent to the one recommended by EFSA. In comparison to the conventional PCR, this new protocol is faster and is currently being applied routinely in our laboratory to all isolates that could potentially be S. Typhimurium. Copyright © 2013 Elsevier B.V. All rights reserved.
Yang, Kyung-Ae; Pei, Renjun; Stojanovic, Milan N.
2016-01-01
We recently optimized a procedure that directly yields aptameric sensors for small molecules in so-called structure-switching format. The protocol has a high success rate, short time, and is sufficiently simple to be readily implemented in a non-specialist laboratory. We provide a stepwise guide to this selection protocol. PMID:27155227
Isolation and Characterization of Extracellular Vesicles from Adult Schistosoma japonicum.
Liu, Juntao; Zhu, Lihui; Wang, Lihui; Chen, Yongjun; Giri, Bikash Ranjan; Li, Jianjun; Cheng, Guofeng
2018-05-22
Extracellular vesicles (EVs) are membranous vesicles released by a variety of cells into the extracellular microenvironment. EVs represent a population of heterogeneous vesicles, whose size range between 40 and 1,000 nm. Accumulated evidence indicated that EVs play important regulatory roles in pathogen-host interactions. A deep understanding of schistosome EVs should provide insights into the mechanisms underlying schistosome-host interactions, enabling development of novel strategies against schistosomiasis. Here, we aim to further study EVs functions in schistosomes by presenting a protocol for the isolation and characterization of EVs from adult Schistosoma japonicum (S. japonicum). EVs were isolated from in vitro culture medium using centrifugation combined with a commercial exosome isolation kit. The isolated S. japonicum EVs (SjEVs) typically possess a diameter of 100 - 400 nm, and are characterized by transmission electronic microscopy and western blotting. The usage of PKH67 dye-labeled SjEVs has demonstrated that SjEVs are internalized by the recipient cells. Overall, our protocol provides an alternative method for isolating EVs from adult schistosomes; the isolated SjEVs may be suitable for functional analysis.
Optic neuritis in paediatric patients: Experience over 27 years and a management protocol.
Monge Galindo, L; Martínez de Morentín, A L; Pueyo Royo, V; García Iñiguez, J P; Sánchez Marco, S; López-Pisón, J; Peña-Segura, J L
2018-03-08
In this article, we present our experience on optic neuritis (ON) and provide a diagnostic/therapeutic protocol, intended to rule out other aetiologies (particularly infection), and a fact sheet for parents. We conducted a descriptive, retrospective study of patients with ON over a 27-year period (1990-2017). A review of the available scientific evidence was performed in order to draft the protocol and fact sheet. Our neuropaediatrics department has assessed 20,744 patients in the last 27 years, of whom 14 were diagnosed with ON: 8 had isolated ON, 1 had multiple sclerosis (MS), 1 had clinically isolated syndrome (CIS), 3 had acute disseminated encephalomyelitis, and 1 had isolated ON and a history of acute disseminated encephalomyelitis one year previously. Patients' age range was 4-13 years; 50% were boys. Eight patients were aged over 10: 7 had isolated ON and 1 had MS. Nine patients had bilateral ON, and 3 had retrobulbar ON. MRI results were normal in 7 patients and showed involvement of the optic nerve only in 2 patients and optic nerve involvement + central nervous system demyelination in 5. Thirteen patients received corticosteroids. One patient had been vaccinated against meningococcus-C the previous month. Progression was favourable, except in the patient with MS. A management protocol and fact sheet are provided. ON usually has a favourable clinical course. In children aged older than 10 years with risk factors for MS or optic neuromyelitis (hyperintensity on brain MRI, oligoclonal bands, anti-NMO antibody positivity, ON recurrence), the initiation of immunomodulatory treatment should be agreed with the neurology department. The protocol is useful for diagnostic decision-making, follow-up, and treatment of this rare disease with potentially major repercussions. The use of protocols and fact sheets is important. Copyright © 2018 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.
Ullah, Mujib; Hamouda, Houda; Stich, Stefan; Sittinger, Michael; Ringe, Jochen
2012-12-01
Administration of chondrogenically differentiated mesenchymal stem cells (MSC) is discussed as a promising approach for the regenerative treatment of injured or diseased cartilage. The high-density pellet culture is the standard culture for chondrogenic differentiation, but cells in pellets secrete extracellular matrix (ECM) that they become entrapped in. Protocols for cell isolation from pellets often result in cell damage and dedifferentiation towards less differentiated MSC. Therefore, our aim was to develop a reliable protocol for the isolation of viable, chondrogenically differentiated MSC from high-density pellet cultures. Human bone marrow MSC were chondrogenically stimulated with transforming growth factor-β3, and the cartilaginous structure of the pellets was verified by alcian blue staining of cartilage proteoglycans, antibody staining of cartilage collagen type II, and quantitative real-time reverse-transcription polymerase chain reaction of the marker genes COL2A1 and SOX9. Trypsin and collagenases II and P were tested alone or in combination, and for different concentrations and times, to find a protocol for optimized pellet digestion. Whereas trypsin was not able to release viable cells, 90-min digestion with 300 U of collagenase II, 20 U of collagenase P, and 2 mM CaCl2 worked quite well and resulted in about 2.5×10(5) cells/pellet. The protocol was further optimized for the separation of released cells and ECM from each other. Cells were alcian blue and collagen type II positive and expressed COL2A1 and SOX9, verifying a chondrogenic character. However, they had different morphological shapes. The ECM was also uniformly alcian blue and collagen type II positive but showed different organizational and structural forms. To conclude, our protocol allows the reliable isolation of a defined number of viable, chondrogenically differentiated MSC from high-density pellet cultures. Such cells, as well as the ECM components, are of interest as research tools and for cartilage tissue engineering.
Villhauer, Alissa L; Lynch, David J; Drake, David R
2017-08-01
Mutans streptococci (MS), specifically Streptococcus mutans (SM) and Streptococcus sobrinus (SS), are bacterial species frequently targeted for investigation due to their role in the etiology of dental caries. Differentiation of S. mutans and S. sobrinus is an essential part of exploring the role of these organisms in disease progression and the impact of the presence of either/both on a subject's caries experience. Of vital importance to the study of these organisms is an identification protocol that allows us to distinguish between the two species in an easy, accurate, and timely manner. While conducting a 5-year birth cohort study in a Northern Plains American Indian tribe, the need for a more rapid procedure for isolating and identifying high volumes of MS was recognized. We report here on the development of an accurate and rapid method for MS identification. Accuracy, ease of use, and material and time requirements for morphological differentiation on selective agar, biochemical tests, and various combinations of PCR primers were compared. The final protocol included preliminary identification based on colony morphology followed by PCR confirmation of species identification using primers targeting regions of the glucosyltransferase (gtf) genes of SM and SS. This method of isolation and identification was found to be highly accurate, more rapid than the previous methodology used, and easily learned. It resulted in more efficient use of both time and material resources. Copyright © 2017 Elsevier B.V. All rights reserved.
Biochemical and physical characterisation of urinary nanovesicles following CHAPS treatment.
Musante, Luca; Saraswat, Mayank; Duriez, Elodie; Byrne, Barry; Ravidà, Alessandra; Domon, Bruno; Holthofer, Harry
2012-01-01
Urinary exosomes represent a precious source of potential biomarkers for disease biology. Currently, the methods for vesicle isolation are severely restricted by the tendency of vesicle entrapment, e.g. by the abundant Tamm-Horsfall protein (THP) polymers. Treatment by reducing agents such as dithiothreitol (DTT) releases entrapped vesicles, thus increasing the final yield. However, this harsh treatment can cause remodelling of all those proteins which feature extra-vesicular domains stabilized by internal disulfide bridges and have detrimental effects on their biological activity. In order to optimize exosomal yield, we explore two vesicle treatment protocols - dithiothreitol (DTT) and 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonic (CHAPS) - applied to the differential centrifugation protocol for exosomal vesicle isolation. The results show that CHAPS treatment does not affect vesicle morphology or exosomal marker distribution, thus eliminating most of THP interference. Moreover, the recovery and preservation of catalytic activity of two trans-membrane proteases, dipeptidyl peptidase IV and nephrilysin, was examined and found to be clearly superior after CHAPS treatment compared to DTT. Finally, proteomic profiling by mass spectrometry (MS) revealed that 76.2% of proteins recovered by CHAPS are common to those seen for DTT treatment, which illustrates underlining similarities between the two approaches. In conclusion, we provide a major improvement to currently-utilized urinary vesicle isolation strategies to allow recovery of urinary vesicles without the deleterious interference of abundant urinary proteins, while preserving typical protein folding and, consequently, the precious biological activity of urinary proteins which serve as valuable biomarkers.
Cisgenesis strongly improves introgression breeding and induced translocation breeding of plants.
Jacobsen, Evert; Schouten, Henk J
2007-05-01
There are two ways for genetic improvement in classical plant breeding: crossing and mutation. Plant varieties can also be improved through genetic modification; however, the present GMO regulations are based on risk assessments with the transgenes coming from non-crossable species. Nowadays, DNA sequence information of crop plants facilitates the isolation of cisgenes, which are genes from crop plants themselves or from crossable species. The increasing number of these isolated genes, and the development of transformation protocols that do not leave marker genes behind, provide an opportunity to improve plant breeding while remaining within the gene pool of the classical breeder. Compared with induced translocation and introgression breeding, cisgenesis is an improvement for gene transfer from crossable plants: it is a one-step gene transfer without linkage drag of other genes, whereas induced translocation and introgression breeding are multiple step gene transfer methods with linkage drag. The similarity of the genes used in cisgenesis compared with classical breeding is a compelling argument to treat cisgenic plants as classically bred plants. In the case of the classical breeding method induced translocation breeding, the insertion site of the genes is a priori unknown, as it is in cisgenesis. This provides another argument to treat cisgenic plants as classically bred plants, by exempting cisgenesis of plants from the GMO legislations.
Elbing, Karen; Brent, Roger
2002-08-01
Detailed protocols are provided for titering and isolating bacterial colonies by serial dilutions, or alternatively by streaking or spreading a plate. Support protocols describe replica plating as well as methods for storing strains as agar stabs or frozen glycerol stocks.
Françoso, Elaine; Gomes, Fernando; Arias, Maria Cristina
2016-07-01
Nuclear mitochondrial DNA insertions (NUMTs) are mitochondrial DNA sequences that have been transferred into the nucleus and are recognized by the presence of indels and stop codons. Although NUMTs have been identified in a diverse range of species, their discovery was frequently accidental. Here, our initial goal was to develop and standardize a simple method for isolating NUMTs from the nuclear genome of a single bee. Subsequently, we tested our new protocol by determining whether the indels and stop codons of the cytochrome c oxidase subunit I (COI) sequence of Melipona flavolineata are of nuclear origin. The new protocol successfully demonstrated the presence of a COI NUMT. In addition to NUMT investigations, the protocol described here will also be very useful for studying mitochondrial mutations related to diseases and for sequencing complete mitochondrial genomes with high read coverage by Next-Generation technology.
Explanatory chapter: how plasmid preparation kits work.
Koontz, Laura
2013-01-01
To isolate plasmid DNA from bacteria using a commercial plasmid miniprep kit (if interested, compare this protocol with Isolation of plasmid DNA from bacteria). Copyright © 2013 Elsevier Inc. All rights reserved.
Toward a better understanding of the lignin isolation process from wood.
Guerra, Anderson; Filpponen, Ilari; Lucia, Lucian A; Saquing, Carl; Baumberger, Stephanie; Argyropoulos, Dimitris S
2006-08-09
The recently developed protocol for isolating enzymatic mild acidolysis lignins (EMAL) coupled with the novel combination of derivatization followed by reductive cleavage (DFRC) and quantitative (31)P NMR spectroscopy were used to better understand the lignin isolation process from wood. The EMAL protocol is shown to offer access at lignin samples that are more representative of the overall lignin present in milled wood. The combination of DFRC/(31)P NMR provided a detailed picture on the effects of the isolation conditions on the lignin structure. More specifically, we have used vibratory and ball milling as the two methods of wood pulverization and have compared their effects on the lignin structures and molecular weights. Vibratory-milling conditions cause substantial lignin depolymerization. Lignin depolymerization occurs via the cleavage of uncondensed beta-aryl ether linkages, while condensed beta-aryl ethers and dibenzodioxocins were found to be resistant to such mechanical action. Condensation and side chain oxidations were induced mechanochemically under vibratory-milling conditions as evidenced by the increased amounts of condensed phenolic hydroxyl and carboxylic acid groups. Alternatively, the mild mechanical treatment offered by ball milling was found not to affect the isolated lignin macromolecular structure. However, the overall lignin yields were found to be compromised when the mechanical action was less intense, necessitating longer milling times under ball-milling conditions. As compared to other lignin preparations isolated from the same batch of milled wood, the yield of EMAL was about four times greater than the corresponding milled wood lignin (MWL) and about two times greater as compared to cellulolytic enzyme lignin (CEL). Molecular weight distribution analyses also pointed out that the EMAL protocol allows the isolation of lignin fractions that are not accessed by any other lignin isolation procedures.
Pham, Kelly L D; Bjornson, Kristie F; Osorio, Marisa; Whitlock, Kathryn B; Massagli, Teresa L
2018-06-01
The incidence of contact isolation for multidrug-resistant organisms is increasing in acute hospitals and inpatient rehabilitation units alike. There is limited evidence on the effect of contact isolation on functional outcomes during inpatient rehabilitation. To determine whether the use of a modified contact isolation protocol (MCI) resulted in noninferior functional outcomes compared with children without contact isolation (NCI) on inpatient rehabilitation. This is a retrospective noninferiority study. One academically affiliated pediatric inpatient rehabilitation unit located in a children's hospital. All children with any diagnosis admitted to inpatient rehabilitation from January 1, 2007, to December 31, 2014. We compared functional outcomes for 2 groups of children. Primary outcome measures included the Functional Independence Measure for Children (WeeFIM) efficiency and the change in the Developmental Functional Quotient (DFQ) for the WeeFIM. Noninferiority margins of 0.63 for the WeeFIM efficiency and 0.092 for the change in DFQ for the WeeFIM were used. There were a total of 949 patients of whom 899 were NCI, 48 MCI, and 2 excluded due to missing information. Patients with MCI had functional outcomes that were noninferior to those with NCI including the WeeFIM efficiency (mean difference 0.002, 95% CI -0.38 to 0.404) and the change in DFQ for the WeeFIM (mean difference -0.05, 95% CI -0.058 to 0.003). The modified contact isolation protocol, having resulted in noninferior functional outcomes in inpatient rehabilitation may provide adequate contact isolation while allowing for noninferior functional outcomes. This may be a guide in the face of an ever-increasing need for contact isolation. III. Copyright © 2018 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.
Primary microglia isolation from mixed glial cell cultures of neonatal rat brain tissue.
Tamashiro, Tami T; Dalgard, Clifton Lee; Byrnes, Kimberly R
2012-08-15
Microglia account for approximately 12% of the total cellular population in the mammalian brain. While neurons and astrocytes are considered the major cell types of the nervous system, microglia play a significant role in normal brain physiology by monitoring tissue for debris and pathogens and maintaining homeostasis in the parenchyma via phagocytic activity. Microglia are activated during a number of injury and disease conditions, including neurodegenerative disease, traumatic brain injury, and nervous system infection. Under these activating conditions, microglia increase their phagocytic activity, undergo morpohological and proliferative change, and actively secrete reactive oxygen and nitrogen species, pro-inflammatory chemokines and cytokines, often activating a paracrine or autocrine loop. As these microglial responses contribute to disease pathogenesis in neurological conditions, research focused on microglia is warranted. Due to the cellular heterogeneity of the brain, it is technically difficult to obtain sufficient microglial sample material with high purity during in vivo experiments. Current research on the neuroprotective and neurotoxic functions of microglia require a routine technical method to consistently generate pure and healthy microglia with sufficient yield for study. We present, in text and video, a protocol to isolate pure primary microglia from mixed glia cultures for a variety of downstream applications. Briefly, this technique utilizes dissociated brain tissue from neonatal rat pups to produce mixed glial cell cultures. After the mixed glial cultures reach confluency, primary microglia are mechanically isolated from the culture by a brief duration of shaking. The microglia are then plated at high purity for experimental study. The principle and protocol of this methodology have been described in the literature. Additionally, alternate methodologies to isolate primary microglia are well described. Homogenized brain tissue may be separated by density gradient centrifugation to yield primary microglia. However, the centrifugation is of moderate length (45 min) and may cause cellular damage and activation, as well as, cause enriched microglia and other cellular populations. Another protocol has been utilized to isolate primary microglia in a variety of organisms by prolonged (16 hr) shaking while in culture. After shaking, the media supernatant is centrifuged to isolate microglia. This longer two-step isolation method may also perturb microglial function and activation. We chiefly utilize the following microglia isolation protocol in our laboratory for a number of reasons: (1) primary microglia simulate in vivo biology more faithfully than immortalized rodent microglia cell lines, (2) nominal mechanical disruption minimizes potential cellular dysfunction or activation, and (3) sufficient yield can be obtained without passage of the mixed glial cell cultures. It is important to note that this protocol uses brain tissue from neonatal rat pups to isolate microglia and that using older rats to isolate microglia can significantly impact the yield, activation status, and functional properties of isolated microglia. There is evidence that aging is linked with microglia dysfunction, increased neuroinflammation and neurodegenerative pathologies, so previous studies have used ex vivo adult microglia to better understand the role of microglia in neurodegenerative diseases where aging is important parameter. However, ex vivo microglia cannot be kept in culture for prolonged periods of time. Therefore, while this protocol extends the life of primary microglia in culture, it should be noted that the microglia behave differently from adult microglia and in vitro studies should be carefully considered when translated to an in vivo setting.
A novel method for isolation of epithelial cells from ovine esophagus for tissue engineering.
Macheiner, Tanja; Kuess, Anna; Dye, Julian; Saxena, Amulya K
2014-01-01
The yield of a critical number of basal epithelial cells with high mitotic rates from native tissue is a challenge in the field of tissue engineering. There are many protocols that use enzymatic methods for isolation of epithelial cells with unsatisfactory results for tissue engineering. This study aimed to develop a protocol for isolating a sufficient number of epithelial cells with a high Proliferating Index from ovine esophagus for tissue engineering applications. Esophageal mucosa was pretreated with dispase-collagenase solution and plated on collagen-coated culture dishes. Distinction of the various types of epithelial cells and developmental stages was done with specific primary antibodies to Cytokeratins and to Proliferating Cell Nuclear Antigen (PCNA). Up to approximately 8100 epithelial cells/mm2 of mucosa tissue were found after one week of migration. Cytokeratin 14 (CK 14) was positive identified in cells even after 83 days. At the same time the Proliferating Index was 71%. Our protocol for isolation of basal epithelial cells was successful to yield sufficient numbers of cells predominantly with proliferative character and without noteworthy negative enzymatic affection. The results at this study offer the possibility of generation critical cell numbers for tissue engineering applications.
Primary Mouse Myoblast Purification using Magnetic Cell Separation.
Sincennes, Marie Claude; Wang, Yu Xin; Rudnicki, Michael A
2017-01-01
Primary myoblasts can be isolated from mouse muscle cell extracts and cultured in vitro. Muscle cells are usually dissociated manually by mincing with razor blades or scissors in a collagenase/dispase solution. Primary myoblasts are then gradually enriched by pre-plating on collagen-coated plates, based on the observation that mouse fibroblasts attach quickly to collagen-coated plates, and are less adherent. Here, we describe an automated muscle dissociation protocol. We also propose an alternative to pre-plating using magnetic bead separation of primary myoblasts, which improve myoblast purity by minimizing fibroblast contamination.
Detection, Isolation, and Identification of Vibrio cholerae from the Environment
Huq, Anwar; Haley, Bradd J.; Taviani, Elisa; Chen, Arlene; Hasan, Nur A.; Colwell, Rita R.
2012-01-01
Recent molecular advances in microbiology have greatly improved the detection of bacterial pathogens in the environment. Improvement and a downward trend in the cost of molecular detection methods have contributed to increased frequency of detection of pathogenic microorganisms where traditional culture-based detection methods have failed. Culture methods also have been greatly improved and the confluence of the two suites of methods provides a powerful tool for detection, isolation, and characterization of pathogens. While molecular detection provides data on the presence and type of pathogens, culturing methods allow a researcher to preserve the organism of interest for “–omics” studies, such as genomic, metabolomic, secretomic, and transcriptomic analysis, which are rapidly becoming more affordable. This has yielded a clearer understanding of the ecology and epidemiology of microorganisms that cause disease. Specifically, important advances have been made over the past several years on isolation, detection, and identification of Vibrio cholerae, the causative agent of cholera in humans. In this unit, we present commonly accepted methods for isolation, detection, and characterization of V. cholerae, providing more extensive knowledge of the ecology and epidemiology of this organism. This unit has been fully revised and updated from the earlier unit (Huq, Grim et al. 2006) with the latest knowledge and additional information not previously included. We have also taken into account of cost of reagents and equipment that may be prohibitive for many researchers and have, therefore, included protocols for all laboratories, including those with limited resources, likely to be located in regions of cholera endemicity. PMID:22875567
An introduction to planar chromatography and its application to natural products isolation.
Gibbons, Simon
2012-01-01
Thin-layer chromatography (TLC) is an easy, inexpensive, rapid, and the most widely used method for the analysis and isolation of small organic natural and synthetic products. It also has use in the biological evaluation of organic compounds, particularly in the areas of antimicrobial and antioxidant metabolites and for the evaluation of acetylcholinesterase inhibitors which have utility in the treatment of Alzheimer's disease. The ease and inexpensiveness of use of this technique, coupled with the ability to rapidly develop separation and bioassay protocols will ensure that TLC will be used for some considerable time alongside conventional instrumental methods. This chapter deals with the basic principles of TLC and describes methods for the analysis and isolation of natural products. Examples of methods for isolation of several classes of natural product are detailed and protocols for TLC bioassays are given.
Isolation of Extracellular Vesicles: General Methodologies and Latest Trends
Konoshenko, Maria Yu.; Laktionov, Pavel P.
2018-01-01
Background Extracellular vesicles (EVs) play an essential role in the communication between cells and transport of diagnostically significant molecules. A wide diversity of approaches utilizing different biochemical properties of EVs and a lack of accepted protocols make data interpretation very challenging. Scope of Review This review consolidates the data on the classical and state-of-the-art methods for isolation of EVs, including exosomes, highlighting the advantages and disadvantages of each method. Various characteristics of individual methods, including isolation efficiency, EV yield, properties of isolated EVs, and labor consumption are compared. Major Conclusions A mixed population of vesicles is obtained in most studies of EVs for all used isolation methods. The properties of an analyzed sample should be taken into account when planning an experiment aimed at studying and using these vesicles. The problem of adequate EVs isolation methods still remains; it might not be possible to develop a universal EV isolation method but the available protocols can be used towards solving particular types of problems. General Significance With the wide use of EVs for diagnosis and therapy of various diseases the evaluation of existing methods for EV isolation is one of the key problems in modern biology and medicine. PMID:29662902
Liu, Ying; Liu, Guoxuan; Yang, Yali; Niu, Sufang; Yang, Fuguang; Yang, Shaoxia; Tang, Jianian; Chen, Jianping
2017-12-01
An efficient and reproducible protocol is described for shoot-bud regeneration and Agrobacterium tumefaciens-mediated genetic transformation of J. curcas. Treating the explants with high concentrations (5-120 mg/L) of TDZ for short durations (5-80 min) before inoculation culture increased significantly the regeneration frequency and improved the quality of the regenerated buds. The highest shoot-buds induction rate (87.35%) was achieved when petiole explants were treated with 20 mg/L TDZ solution for 20 min and inoculated on hormone-free MS medium for 30 days. Regenerated shoots of 0.5 cm or a little longer were isolated and grafted to seedling stocks of the same species, and then the grafted plantlets were planted on half-strength MS medium containing 0.1 mg/L IBA and 2 mg/L sodium nitroprusside (SNP). This grafting strategy was found to be very effective, to obtain that healthy grafted plantlets ready for acclimatization within 20 days. By the above mentioned protocol and with general Agrobacterium - mediated genetic transformation methods only 65 days were needed to obtain intact transgenic plants.
A Secure Region-Based Geographic Routing Protocol (SRBGR) for Wireless Sensor Networks
Adnan, Ali Idarous; Hanapi, Zurina Mohd; Othman, Mohamed; Zukarnain, Zuriati Ahmad
2017-01-01
Due to the lack of dependency for routing initiation and an inadequate allocated sextant on responding messages, the secure geographic routing protocols for Wireless Sensor Networks (WSNs) have attracted considerable attention. However, the existing protocols are more likely to drop packets when legitimate nodes fail to respond to the routing initiation messages while attackers in the allocated sextant manage to respond. Furthermore, these protocols are designed with inefficient collection window and inadequate verification criteria which may lead to a high number of attacker selections. To prevent the failure to find an appropriate relay node and undesirable packet retransmission, this paper presents Secure Region-Based Geographic Routing Protocol (SRBGR) to increase the probability of selecting the appropriate relay node. By extending the allocated sextant and applying different message contention priorities more legitimate nodes can be admitted in the routing process. Moreover, the paper also proposed the bound collection window for a sufficient collection time and verification cost for both attacker identification and isolation. Extensive simulation experiments have been performed to evaluate the performance of the proposed protocol in comparison with other existing protocols. The results demonstrate that SRBGR increases network performance in terms of the packet delivery ratio and isolates attacks such as Sybil and Black hole. PMID:28121992
A Secure Region-Based Geographic Routing Protocol (SRBGR) for Wireless Sensor Networks.
Adnan, Ali Idarous; Hanapi, Zurina Mohd; Othman, Mohamed; Zukarnain, Zuriati Ahmad
2017-01-01
Due to the lack of dependency for routing initiation and an inadequate allocated sextant on responding messages, the secure geographic routing protocols for Wireless Sensor Networks (WSNs) have attracted considerable attention. However, the existing protocols are more likely to drop packets when legitimate nodes fail to respond to the routing initiation messages while attackers in the allocated sextant manage to respond. Furthermore, these protocols are designed with inefficient collection window and inadequate verification criteria which may lead to a high number of attacker selections. To prevent the failure to find an appropriate relay node and undesirable packet retransmission, this paper presents Secure Region-Based Geographic Routing Protocol (SRBGR) to increase the probability of selecting the appropriate relay node. By extending the allocated sextant and applying different message contention priorities more legitimate nodes can be admitted in the routing process. Moreover, the paper also proposed the bound collection window for a sufficient collection time and verification cost for both attacker identification and isolation. Extensive simulation experiments have been performed to evaluate the performance of the proposed protocol in comparison with other existing protocols. The results demonstrate that SRBGR increases network performance in terms of the packet delivery ratio and isolates attacks such as Sybil and Black hole.
2011-01-01
Background To simplify the methodology for the isolation of Campylobacter spp. from retail broiler meat, we evaluated 108 samples (breasts and thighs) using an unpaired sample design. The enrichment broths were incubated under aerobic conditions (subsamples A) and for comparison under microaerobic conditions (subsamples M) as recommended by current reference protocols. Sensors were used to measure the dissolved oxygen (DO) in the broth and the percentage of oxygen (O2) in the head space of the bags used for enrichment. Campylobacter isolates were identified with multiplex PCR assays and typed using pulsed-field gel electrophoresis (PFGE). Ribosomal intergenic spacer analyses (RISA) and denaturing gradient gel electrophoresis (DGGE) were used to study the bacterial communities of subsamples M and A after 48 h enrichment. Results The number of Campylobacter positive subsamples were similar for A and M when all samples were combined (P = 0.81) and when samples were analyzed by product (breast: P = 0.75; thigh: P = 1.00). Oxygen sensors showed that DO values in the broth were around 6 ppm and O2 values in the head space were 14-16% throughout incubation. PFGE demonstrated high genomic similarity of isolates in the majority of the samples in which isolates were obtained from subsamples A and M. RISA and DGGE results showed a large variability in the bacterial populations that could be attributed to sample-to-sample variations and not enrichment conditions (aerobic or microaerobic). These data also suggested that current sampling protocols are not optimized to determine the true number of Campylobacter positive samples in retail boiler meat. Conclusions Decreased DO in enrichment broths is naturally achieved. This simplified, cost-effective enrichment protocol with aerobic incubation could be incorporated into reference methods for the isolation of Campylobacter spp. from retail broiler meat. PMID:21812946
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meyer, Jeremy, E-mail: jeremy.meyer@hcuge.ch; Unit of Surgical Research, University of Geneva, Rue Michel-Servet 1, 1206 Genève; Lacotte, Stéphanie, E-mail: stephanie.lacotte@unige.ch
The objective of the present study was to develop an accurate and reproducible method for liver sinusoidal endothelial cell (LSEC) isolation in mice. Non-parenchymal cells were isolated using a modified two-step collagenase digestion combined with Optiprep density gradient centrifugation. LSEC were further purified using two prevalent methods, short-term selective adherence and CD146+ magnetic-activated cell sorting (MACS), and compared in terms of cell yield, viability and purity to our purification technique using CD11b cell depletion combined with long-term selective adherence. LSEC purification using our technique allowed to obtain 7.07±3.80 million LSEC per liver, while CD146+ MACS and short-term selective adherence yieldedmore » 2.94±1.28 and 0.99±0.66 million LSEC, respectively. Purity of the final cell preparation reached 95.10±2.58% when using our method. In contrast, CD146+ MACS and short-term selective adherence gave purities of 86.75±3.26% and 47.95±9.82%, respectively. Similarly, contamination by non-LSEC was the lowest when purification was performed using our technique, with a proportion of contaminating macrophages of only 1.87±0.77%. Further, isolated cells analysed by scanning electron microscopy presented typical LSEC fenestrations organized in sieve plates, demonstrating that the technique allowed to isolate bona fide LSEC. In conclusion, we described a reliable and reproducible technique for the isolation of high yields of pure LSEC in mice. This protocol provides an efficient method to prepare LSEC for studying their biological functions. - Highlights: • This protocol provides an efficient method to prepare primary mouse LSEC for studying their biological functions. • The liver cell dispersion step was improved by performing a retrograde cannulation of the liver. • The cell yield and the purity obtained were higher than comparative techniques in mice. • Contaminating macrophages were removed by introducing a CD11b- magnetic –activated cell sorting step.« less
NASA Astrophysics Data System (ADS)
Lane, Rebecca E.; Korbie, Darren; Anderson, Will; Vaidyanathan, Ramanathan; Trau, Matt
2015-01-01
Exosomes are vesicles which have garnered interest due to their diagnostic and therapeutic potential. Isolation of pure yields of exosomes from complex biological fluids whilst preserving their physical characteristics is critical for downstream applications. In this study, we use 100 nm-liposomes from 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and cholesterol as a model system as a model system to assess the effect of exosome isolation protocols on vesicle recovery and size distribution using a single-particle analysis method. We demonstrate that liposome size distribution and ζ-potential are comparable to extracted exosomes, making them an ideal model for comparison studies. Four different purification protocols were evaluated, with liposomes robustly isolated by three of them. Recovered yields varied and liposome size distribution was unaltered during processing, suggesting that these protocols do not induce particle aggregation. This leads us to conclude that the size distribution profile and characteristics of vesicles are stably maintained during processing and purification, suggesting that reports detailing how exosomes derived from tumour cells differ in size to those from normal cells are reporting a real phenomenon. However, we hypothesize that larger particles present in most purified exosome samples represent co-purified contaminating non-exosome debris. These isolation techniques are therefore likely nonspecific and may co-isolate non-exosome material of similar physical properties.
Akahori, H; Ozai, M; Ida, M; Shibuya, K; Kato, T; Miyazaki, H
1998-02-01
Thrombopoietin (TPO) is the recently isolated lineage-dominant hematopoietic factor that plays a pivotal role in the regulation of megakaryocytopoiesis and thrombopoiesis. In vivo studies have shown that daily multiple injections of pegylated human megakaryocyte growth and development factor (PEG-rHuMGDF), a truncated molecule related to human TPO, modified with polyethylene glycol, greatly improve thrombocytopenia and in most cases anemia and neutropenia in myelosuppressed animal models. In this study, we further examined various administration protocols of PEG-rHuMGDF on thrombocytopenia in mice treated with a combination of irradiation and carboplatin. After the myelosuppressive treatment on Day 0, mice received the same amount of PEG-rHuMGDF beginning on Day 1 by a single, 3 times (on alternate days), or 7 day daily administration. A single injection of PEG-rHuMGDF significantly reduced the severity and duration of thrombocytopenia and anemia with a concomitant accelerated recovery of megakaryocytic and erythroid progenitors in the bone marrow, similar to the 2 other administration protocols. As the start of a single injection of PEG-rHuMGDF was delayed, its therapeutic effects were attenuated. These results indicate that an administration of PEG-rHuMGDF at an earlier time after the myelosuppressive treatment is necessary to improve thrombocytopenia and anemia.
Purified enzymes improve isolation and characterization of the adult thymic epithelium.
Seach, Natalie; Wong, Kahlia; Hammett, Maree; Boyd, Richard L; Chidgey, Ann P
2012-11-30
The reproducible isolation and accurate characterization of thymic epithelial cell (TEC) subsets is of critical importance to the ongoing study of thymopoiesis and its functional decline with age. The study of adult TEC, however, is significantly hampered due to the severely low stromal to hematopoietic cell ratio. Non-biased digestion and enrichment protocols are thus essential to ensure optimal cell yield and accurate representation of stromal subsets, as close as possible to their in vivo representation. Current digestion protocols predominantly involve diverse, relatively impure enzymatic variants of crude collagenase and collagenase/dispase (col/disp) preparations, which have variable efficacy and are often suboptimal in their ability to mediate complete digestion of thymus tissue. To address these issues we compared traditional col/disp preparations with the latest panel of Liberase products that contain a blend of highly purified collagenase and neutral protease enzymes. Liberase enzymes revealed a more rapid, complete dissociation of thymus tissue; minimizing loss of viability and increasing recovery of thymic stromal cell (TSC) elements. In particular, the recovery and viability of TEC, notably the rare cortical subsets, were significantly enhanced with Liberase products containing medium to high levels of thermolysin. The improved stromal dissociation led to numerically increased TEC yield and total TEC RNA isolated from pooled digests of adult thymus. Furthermore, the increased recovery of TEC enhanced resolution and quantification of TEC subsets in both adult and aged mice, facilitating flow cytometric analysis on a per thymus basis. We further refined the adult TEC phenotype by correlating surface expression of known TEC markers, with expression of intracellular epithelial lineage markers, Keratin 5 and Keratin 8. The data reveal more extensive expression of K8 than previously recognized and indicates considerable heterogeneity still exists within currently defined adult TEC subsets. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.
Rasmussen, Stinne Eika; Nebsbjerg, Mette Amalie; Krogh, Lise Qvirin; Bjørnshave, Katrine; Krogh, Kristian; Povlsen, Jonas Agerlund; Riddervold, Ingunn Skogstad; Grøfte, Thorbjørn; Kirkegaard, Hans; Løfgren, Bo
2017-01-01
Emergency dispatchers use protocols to instruct bystanders in cardiopulmonary resuscitation (CPR). Studies changing one element in the dispatcher's protocol report improved CPR quality. Whether several changes interact is unknown and the effect of combining multiple changes previously reported to improve CPR quality into one protocol remains to be investigated. We hypothesize that a novel dispatch protocol, combining multiple beneficial elements improves CPR quality compared with a standard protocol. A novel dispatch protocol was designed including wording on chest compressions, using a metronome, regular encouragements and a 10-s rest each minute. In a simulated cardiac arrest scenario, laypersons were randomized to perform single-rescuer CPR guided with the novel or the standard protocol. a composite endpoint of time to first compression, hand position, compression depth and rate and hands-off time (maximum score: 22 points). Afterwards participants answered a questionnaire evaluating the dispatcher assistance. The novel protocol (n=61) improved CPR quality score compared with the standard protocol (n=64) (mean (SD): 18.6 (1.4)) points vs. 17.5 (1.7) points, p<0.001. The novel protocol resulted in deeper chest compressions (mean (SD): 58 (12)mm vs. 52 (13)mm, p=0.02) and improved rate of correct hand position (61% vs. 36%, p=0.01) compared with the standard protocol. In both protocols hands-off time was short. The novel protocol improved motivation among rescuers compared with the standard protocol (p=0.002). Participants guided with a standard dispatch protocol performed high quality CPR. A novel bundle of care protocol improved CPR quality score and motivation among rescuers. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
USDA-ARS?s Scientific Manuscript database
Non-typhoid Salmonella is frequently associated with dairy cattle and their environment. Despite well-developed milking hygiene protocols, fecal contamination can occur and Salmonella has often been isolated from bulk milk. Salmonella isolates were recovered from US bulk tank milk as part of the NAH...
Andersen, Natalia D.; Srinivas, Shruthi; Piñero, Gonzalo; Monje, Paula V.
2016-01-01
We herein developed a protocol for the rapid procurement of adult nerve-derived Schwann cells (SCs) that was optimized to implement an immediate enzymatic dissociation of fresh nerve tissue while maintaining high cell viability, improving yields and minimizing fibroblast and myelin contamination. This protocol introduces: (1) an efficient method for enzymatic cell release immediately after removal of the epineurium and extensive teasing of the nerve fibers; (2) an adaptable drop-plating method for selective cell attachment, removal of myelin debris, and expansion of the initial SC population in chemically defined medium; (3) a magnetic-activated cell sorting purification protocol for rapid and effective fibroblast elimination; and (4) an optional step of cryopreservation for the storage of the excess of cells. Highly proliferative SC cultures devoid of myelin and fibroblast growth were obtained within three days of nerve processing. Characterization of the initial, expanded, and cryopreserved cell products confirmed maintenance of SC identity, viability and growth rates throughout the process. Most importantly, SCs retained their sensitivity to mitogens and potential for differentiation even after cryopreservation. To conclude, this easy-to-implement and clinically relevant protocol allows for the preparation of expandable homogeneous SC cultures while minimizing time, manipulation of the cells, and exposure to culture variables. PMID:27549422
Isolation of skeletal muscle stem cells by fluorescence-activated cell sorting.
Liu, Ling; Cheung, Tom H; Charville, Gregory W; Rando, Thomas A
2015-10-01
The prospective isolation of purified stem cell populations has dramatically altered the field of stem cell biology, and it has been a major focus of research across tissues in different organisms. Muscle stem cells (MuSCs) are now among the most intensely studied stem cell populations in mammalian systems, and the prospective isolation of these cells has allowed cellular and molecular characterizations that were not dreamed of a decade ago. In this protocol, we describe how to isolate MuSCs from limb muscles of adult mice by fluorescence-activated cell sorting (FACS). We provide a detailed description of the physical and enzymatic dissociation of mononucleated cells from limb muscles, a procedure that is essential in order to maximize cell yield. We also describe a FACS-based method that is used subsequently to obtain highly pure populations of either quiescent or activated MuSCs (VCAM(+)CD31(-)CD45(-)Sca1(-)). The isolation process takes ∼5-6 h to complete. The protocol also allows for the isolation of endothelial cells, hematopoietic cells and mesenchymal stem cells from muscle tissue.
Sulaiman, Irshad M; Torres, Patricia; Simpson, Steven; Kerdahi, Khalil; Ortega, Ynes
2013-04-01
We have described the development of a 2-step nested PCR protocol based on the characterization of the 70-kDa heat shock protein (HSP70) gene for rapid detection of the human-pathogenic Cyclospora cayetanensis parasite. We tested and validated these newly designed primer sets by PCR amplification followed by nucleotide sequencing of PCR-amplified HSP70 fragments belonging to 16 human C. cayetanensis isolates from 3 different endemic regions that include Nepal, Mexico, and Peru. No genetic polymorphism was observed among the isolates at the characterized regions of the HSP70 locus. This newly developed HSP70 gene-based nested PCR protocol provides another useful genetic marker for the rapid detection of C. cayetanensis in the future.
Kulkarni, Sughosh S; Madalgi, Radhika; Ajantha, Ganavalli S; Kulkarni, Raghavendra D
2017-01-01
Acinetobacter is grouped under nonfermenting Gram-negative bacilli. It is increasingly isolated from pathological samples. The ability of this genus to acquire drug resistance and spread in the hospital settings is posing a grave problem in healthcare. Specific treatment protocols are advocated for Acinetobacter infections. Hence, rapid identification and drug susceptibility profiling are critical in the management of these infections. To standardize an in-house polymerase chain reaction (PCR) for identification of genus Acinetobacter and to compare PCR with two protocols for its phenotypic identification. A total of 96 clinical isolates of Acinetobacter were included in the study. An in-house PCR for genus level identification of Acinetobacter was standardized. All the isolates were phenotypically identified by two protocols. The results of PCR and phenotypic identification protocols were compared. The in-house PCR standardized was highly sensitive and specific for the genus Acinetobacter . There was 100% agreement between the phenotypic and molecular identification of the genus. The preliminary identification tests routinely used in clinical laboratories were also in complete agreement with phenotypic and molecular identification. The in-house PCR for genus level identification is specific and sensitive. However, it may not be essential for routine identification as the preliminary phenotypic identification tests used in the clinical laboratory reliably identify the genus Acinetobacter .
Isolation of PCR quality microbial community DNA from heavily contaminated environments.
Gunawardana, Manjula; Chang, Simon; Jimenez, Abraham; Holland-Moritz, Daniel; Holland-Moritz, Hannah; La Val, Taylor P; Lund, Craig; Mullen, Madeline; Olsen, John; Sztain, Terra A; Yoo, Jennifer; Moss, John A; Baum, Marc M
2014-07-01
Asphalts, biochemically degraded oil, contain persistent, water-soluble compounds that pose a significant challenge to the isolation of PCR quality DNA. The adaptation of existing DNA purification protocols and commercial kits proved unsuccessful at overcoming this hurdle. Treatment of aqueous asphalt extracts with a polyamide resin afforded genomic microbial DNA templates that could readily be amplified by PCR. Physicochemically distinct asphalt samples from five natural oil seeps successfully generated the expected 291 bp amplicons targeting a region of the 16S rRNA gene, illustrating the robustness of the method. DNA recovery yields were in the 50-80% range depending on how the asphalt sample was seeded with exogenous DNA. The scope of the new method was expanded to include soil with high humic acid content. DNA from soil samples spiked with a range of humic acid concentrations was extracted with a commercial kit followed by treatment with the polyamide resin. The additional step significantly improved the purity of the DNA templates, especially at high humic acid concentrations, based on qPCR analysis of the bacterial 16S rRNA genes. The new method has the advantages of being inexpensive, simple, and rapid and should provide a valuable addition to protocols in the field of petroleum and soil microbiology. Copyright © 2014 Elsevier B.V. All rights reserved.
ERIC Educational Resources Information Center
Paez-Blarrina, Marisa; Luciano, Carmen; Gutierrez-Martinez, Olga; Valdivia, Sonsoles; Rodriguez-Valverde, Miguel; Ortega, Jose
2008-01-01
This study compares the effect of an acceptance-based protocol (ACT) and a cognitive control-based (CONT) protocol on three measures of pain coping: tolerance, self-report, and believability. Specific methodological controls were employed to further isolate the role of the value of participating in a pain task, compared to previous investigations…
Greening, David W; Xu, Rong; Ji, Hong; Tauro, Bow J; Simpson, Richard J
2015-01-01
Exosomes are 40-150 nm extracellular vesicles that are released from a multitude of cell types, and perform diverse cellular functions including intercellular communication, antigen presentation, and transfer of tumorigenic proteins, mRNA and miRNA. Exosomes are important regulators of the cellular niche, and their altered characteristics in many diseases, such as cancer, suggest their importance for diagnostic and therapeutic applications, and as drug delivery vehicles. Exosomes have been purified from biological fluids and in vitro cell cultures using a variety of strategies and techniques. In this chapter, we reveal the protocol and key insights into the isolation, purification and characterization of exosomes, distinct from shed microvesicles and apoptotic blebs. Using the colorectal cancer cell line LIM1863 as a cell model, a comprehensive evaluation of exosome isolation methods including ultracentrifugation (UC-Exos), OptiPrep™ density-based separation (DG-Exos), and immunoaffinity capture using anti-EpCAM-coated magnetic beads (IAC-Exos) were examined. All exosome isolation methodologies contained 40-150 nm vesicles based on electron microscopy, and positive for exosome markers (Alix, TSG101, HSP70) based on immunoblotting. This protocol employed a proteomic profiling approach to characterize the protein composition of exosomes, and label-free spectral counting to evaluate the effectiveness of each method in exosome isolation. Based on the number of MS/MS spectra identified for exosome markers and proteins associated with their biogenesis, trafficking, and release, IAC-Exos was shown to be the most effective method to isolate exosomes. However, the use of density-based separation (DG-Exos) provides significant advantages for exosome isolation when the use of immunoaffinity capture is limited (due to antibody availability and suitability of exosome markers).
Ghodbane, Ramzi; Asmar, Shady; Betzner, Marlena; Linet, Marie; Pierquin, Joseph; Raoult, Didier; Drancourt, Michel
2015-08-01
Culture remains the cornerstone of diagnosis for pulmonary tuberculosis, but the fastidiousness of Mycobacterium tuberculosis may delay culture-based diagnosis for weeks. We evaluated the performance of real-time high-resolution imaging for the rapid detection of M. tuberculosis colonies growing on a solid medium. A total of 50 clinical specimens, including 42 sputum specimens, 4 stool specimens, 2 bronchoalveolar lavage fluid specimens, and 2 bronchial aspirate fluid specimens were prospectively inoculated into (i) a commercially available Middlebrook broth and evaluated for mycobacterial growth indirectly detected by measuring oxygen consumption (standard protocol) and (ii) a home-made solid medium incubated in an incubator featuring real-time high-resolution imaging of colonies (real-time protocol). Isolates were identified by Ziehl-Neelsen staining and matrix-assisted laser desorption ionization-time of flight mass spectrometry. Use of the standard protocol yielded 14/50 (28%) M. tuberculosis isolates, which is not significantly different from the 13/50 (26%) M. tuberculosis isolates found using the real-time protocol (P = 1.00 by Fisher's exact test), and the contamination rate of 1/50 (2%) was not significantly different from the contamination rate of 2/50 (4%) using the real-time protocol (P = 1.00). The real-time imaging protocol showed a 4.4-fold reduction in time to detection, 82 ± 54 h versus 360 ± 142 h (P < 0.05). These preliminary data give the proof of concept that real-time high-resolution imaging of M. tuberculosis colonies is a new technology that shortens the time to growth detection and the laboratory diagnosis of pulmonary tuberculosis. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Comparison of protocols measuring diffusion and partition coefficients in the stratum corneum.
Rothe, H; Obringer, C; Manwaring, J; Avci, C; Wargniez, W; Eilstein, J; Hewitt, N; Cubberley, R; Duplan, H; Lange, D; Jacques-Jamin, C; Klaric, M; Schepky, A; Grégoire, S
2017-07-01
Partition (K) and diffusion (D) coefficients are important to measure for the modelling of skin penetration of chemicals through the stratum corneum (SC). We compared the feasibility of three protocols for the testing of 50 chemicals in our main studies, using three cosmetics-relevant model chemicals with a wide range of logP values. Protocol 1: SC concentration-depth profile using tape-stripping (measures K SC/v and D SC /H SC 2 , where H SC is the SC thickness); Protocol 2A: incubation of isolated SC with chemical (direct measurement of K SC/v only) and Protocol 2B: diffusion through isolated SC mounted on a Franz cell (measures K SC/v and D SC /H SC 2 , and is based on Fick's laws). K SC/v values for caffeine and resorcinol using Protocol 1 and 2B were within 30% of each other, values using Protocol 2A were ~two-fold higher, and all values were within 10-fold of each other. Only indirect determination of K SC/v by Protocol 2B was different from the direct measurement of K SC/v by Protocol 2A and Protocol 1 for 7-EC. The variability of K SC/v for all three chemicals using Protocol 2B was higher compared to Protocol 1 and 2A. D SC /H SC 2 values for the three chemicals were of the same order of magnitude using all three protocols. Additionally, using Protocol 1, there was very little difference between parameters measured in pig and human SC. In conclusion, K SC/v, and D SC values were comparable using different methods. Pig skin might be a good surrogate for human skin for the three chemicals tested. Copyright © 2017 The Authors Journal of Applied Toxicology published by John Wiley & Sons Ltd. Copyright © 2017 The Authors Journal of Applied Toxicology published by John Wiley & Sons Ltd.
Matrone, M.; Keid, L.B.; Rocha, V.C.M.; Vejarano, M.P.; Ikuta, C.Y.; Rodriguez, C.A.R.; Ferreira, F.; Dias, R.A.; Ferreira Neto, J.S
2009-01-01
The objective of the present study was to improve the detection of B. abortus by PCR in organs of aborted fetuses from infected cows, an important mechanism to find infected herds on the eradication phase of the program. So, different DNA extraction protocols were compared, focusing the PCR detection of B. abortus in clinical samples collected from aborted fetuses or calves born from cows challenged with the 2308 B. abortus strain. Therefore, two gold standard groups were built based on classical bacteriology, formed from: 32 lungs (17 positives), 26 spleens (11 positives), 23 livers (8 positives) and 22 bronchial lymph nodes (7 positives). All samples were submitted to three DNA extraction protocols, followed by the same amplification process with the primers B4 and B5. From the accumulated results for organ, the proportion of positives for the lungs was higher than the livers (p=0.04) or bronchial lymph nodes (p=0.004) and equal to the spleens (p=0.18). From the accumulated results for DNA extraction protocol, the proportion of positives for the Boom protocol was bigger than the PK (p< 0.0001) and GT (p=0.0004). There was no difference between the PK and GT protocols (p=0.5). Some positive samples from the classical bacteriology were negative to the PCR and vice-versa. Therefore, the best strategy for B. abortus detection in the organs of aborted fetuses or calves born from infected cows is the use, in parallel, of isolation by classical bacteriology and the PCR, with the DNA extraction performed by the Boom protocol. PMID:24031391
Method optimization for fathead minnow (Pimephales promelas) liver S9 isolation
Standard protocols have been proposed to assess metabolic stability in rainbow trout liver S9 fractions. Using in vitro substrate depletion assays, in vitro intrinsic clearance rates can be calculated for a variety of study compounds. Existing protocols suggest potential adaptati...
RNA Isolation from Plant Tissues: A Hands-On Laboratory Experimental Experience for Undergraduates
ERIC Educational Resources Information Center
Zhang, Nianhui; Yu, Dong; Zhu, Xiaofeng
2018-01-01
The practice of RNA isolation in undergraduate experimental courses is rare because of the existence of robust, ubiquitous and stable ribonucleases. We reported here modifications to our original protocol for RNA isolation from plant tissues, including the recovery of nucleic acids by ethanol precipitation at 0 degrees C for 10 min and the…
Sarcolipin overexpression improves muscle energetics and reduces fatigue
Sopariwala, Danesh H.; Pant, Meghna; Shaikh, Sana A.; Goonasekera, Sanjeewa A.; Molkentin, Jeffery D.; Weisleder, Noah; Ma, Jianjie; Pan, Zui
2015-01-01
Sarcolipin (SLN) is a regulator of sarcoendoplasmic reticulum calcium ATPase in skeletal muscle. Recent studies using SLN-null mice have identified SLN as a key player in muscle thermogenesis and metabolism. In this study, we exploited a SLN overexpression (SlnOE) mouse model to determine whether increased SLN level affected muscle contractile properties, exercise capacity/fatigue, and metabolic rate in whole animals and isolated muscle. We found that SlnOE mice are more resistant to fatigue and can run significantly longer distances than wild-type (WT). Studies with isolated extensor digitorum longus (EDL) muscles showed that SlnOE EDL produced higher twitch force than WT. The force-frequency curves were not different between WT and SlnOE EDLs, but at lower frequencies the pyruvate-induced potentiation of force was significantly higher in SlnOE EDL. SLN overexpression did not alter the twitch and force-frequency curve in isolated soleus muscle. However, during a 10-min fatigue protocol, both EDL and soleus from SlnOE mice fatigued significantly less than WT muscles. Interestingly, SlnOE muscles showed higher carnitine palmitoyl transferase-1 protein expression, which could enhance fatty acid metabolism. In addition, lactate dehydrogenase expression was higher in SlnOE EDL, suggesting increased glycolytic capacity. We also found an increase in store-operated calcium entry (SOCE) in isolated flexor digitorum brevis fibers of SlnOE compared with WT mice. These data allow us to conclude that increased SLN expression improves skeletal muscle performance during prolonged muscle activity by increasing SOCE and muscle energetics. PMID:25701006
Ducret, Maxime; Fabre, Hugo; Degoul, Olivier; Atzeni, Gianluigi; McGuckin, Colin; Forraz, Nico; Alliot-Licht, Brigitte; Mallein-Gerin, Frédéric; Perrier-Groult, Emeline; Farges, Jean-Christophe
2015-01-01
In recent years, mesenchymal cell-based products have been developed to improve surgical therapies aimed at repairing human tissues. In this context, the tooth has recently emerged as a valuable source of stem/progenitor cells for regenerating orofacial tissues, with easy access to pulp tissue and high differentiation potential of dental pulp mesenchymal cells. International guidelines now recommend the use of standardized procedures for cell isolation, storage and expansion in culture to ensure optimal reproducibility, efficacy and safety when cells are used for clinical application. However, most dental pulp cell-based medicinal products manufacturing procedures may not be fully satisfactory since they could alter the cells biological properties and the quality of derived products. Cell isolation, enrichment and cryopreservation procedures combined to long-term expansion in culture media containing xeno- and allogeneic components are known to affect cell phenotype, viability, proliferation and differentiation capacities. This article focuses on current manufacturing strategies of dental pulp cell-based medicinal products and proposes a new protocol to improve efficiency, reproducibility and safety of these strategies. PMID:26300779
Gu, Haihui; Huang, Xia; Xu, Jing; Song, Lili; Liu, Shuping; Zhang, Xiao-Bing; Yuan, Weiping; Li, Yanxin
2018-06-15
Generation of induced pluripotent stem cells (iPSCs) from human peripheral blood provides a convenient and low-invasive way to obtain patient-specific iPSCs. The episomal vector is one of the best approaches for reprogramming somatic cells to pluripotent status because of its simplicity and affordability. However, the efficiency of episomal vector reprogramming of adult peripheral blood cells is relatively low compared with cord blood and bone marrow cells. In the present study, integration-free human iPSCs derived from peripheral blood were established via episomal technology. We optimized mononuclear cell isolation and cultivation, episomal vector promoters, and a combination of transcriptional factors to improve reprogramming efficiency. Here, we improved the generation efficiency of integration-free iPSCs from human peripheral blood mononuclear cells by optimizing the method of isolating mononuclear cells from peripheral blood, by modifying the integration of culture medium, and by adjusting the duration of culture time and the combination of different episomal vectors. With this optimized protocol, a valuable asset for banking patient-specific iPSCs has been established.
Fojtu, Michaela; Gumulec, Jaromir; Balvan, Jan; Raudenska, Martina; Sztalmachova, Marketa; Polanska, Hana; Smerkova, Kristyna; Adam, Vojtech; Kizek, Rene; Masarik, Michal
2014-02-01
Determination of serum mRNA gained a lot of attention in recent years, particularly from the perspective of disease markers. Streptavidin-modified paramagnetic particles (SMPs) seem an interesting technique, mainly due to possible automated isolation and high efficiency. The aim of this study was to optimize serum isolation protocol to reduce the consumption of chemicals and sample volume. The following factors were optimized: amounts of (i) paramagnetic particles, (ii) oligo(dT)20 probe, (iii) serum, and (iv) the binding sequence (SMPs, oligo(dT)20 , serum vs. oligo(dT)20 , serum and SMPs). RNA content was measured, and the expression of metallothionein-2A as possible prostate cancer marker was analyzed to demonstrate measurable RNA content with ability for RT-PCR detection. Isolation is possible on serum volume range (10-200 μL) without altering of efficiency or purity. Amount of SMPs can be reduced up to 5 μL, with optimal results within 10-30 μL SMPs. Volume of oligo(dT)20 does not affect efficiency, when used within 0.1-0.4 μL. This optimized protocol was also modified to fit needs of automated one-step single-tube analysis with identical efficiency compared to conventional setup. One-step analysis protocol is considered a promising simplification, making RNA isolation suitable for automatable process. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Establishment of Canine-Derived Giardia duodenalis Isolates in Culture.
Tysnes, Kristoffer R; Robertson, Lucy J
2016-06-01
Researchers continue to rely on axenic cultivation of Giardia duodenalis trophozoites in vitro to study the life cycle and host-parasite interactions of G. duodenalis and to develop vaccines and drugs to prevent and treat giardiasis. The majority of in vitro studies of G. duodenalis have used a small subset of isolates, mostly of assemblage A, and these isolates are usually originally isolated from humans. The most commonly used isolate for lab studies is known as WB. Canine giardiasis is a disease of veterinary importance, but it may also be of relevance in zoonotic transmission. Few G. duodenalis isolates from dogs have been adapted to in vitro culture, probably because the methods used are not suitable for the canine-specific genotypes that tend to dominate in most dog populations. In the current study, an experimental approach to cultivating canine-derived isolates of G. duodenalis was attempted by modification of the standard protocol based on physiological differences between the human and canine digestive system. An adapted method is described for improving the rate of in vitro excystation of cysts isolated from dogs by chemically weakening the cyst wall. A new canine-derived assemblage A G. duodenalis isolate was successfully adapted to axenic culture by using this method; the dog apparently had a mixed infection of assemblages A and D, but the assemblage A successfully outcompeted the assemblage D under conditions of in vitro culture. Based on the results, reasons regarding why humans do not seem to be suitable hosts for G. duodenalis in assemblages C and D are discussed.
Dan, Tong; Liu, Wenjun; Sun, Zhihong; Lv, Qiang; Xu, Haiyan; Song, Yuqin; Zhang, Heping
2014-06-09
Economically, Leuconostoc lactis is one of the most important species in the genus Leuconostoc. It plays an important role in the food industry including the production of dextrans and bacteriocins. Currently, traditional molecular typing approaches for characterisation of this species at the isolate level are either unavailable or are not sufficiently reliable for practical use. Multilocus sequence typing (MLST) is a robust and reliable method for characterising bacterial and fungal species at the molecular level. In this study, a novel MLST protocol was developed for 50 L. lactis isolates from Mongolia and China. Sequences from eight targeted genes (groEL, carB, recA, pheS, murC, pyrG, rpoB and uvrC) were obtained. Sequence analysis indicated 20 different sequence types (STs), with 13 of them being represented by a single isolate. Phylogenetic analysis based on the sequences of eight MLST loci indicated that the isolates belonged to two major groups, A (34 isolates) and B (16 isolates). Linkage disequilibrium analyses indicated that recombination occurred at a low frequency in L. lactis, indicating a clonal population structure. Split-decomposition analysis indicated that intraspecies recombination played a role in generating genotypic diversity amongst isolates. Our results indicated that MLST is a valuable tool for typing L. lactis isolates that can be used for further monitoring of evolutionary changes and population genetics.
Isolation of monomeric photosystem II that retains the subunit PsbS.
Haniewicz, Patrycja; De Sanctis, Daniele; Büchel, Claudia; Schröder, Wolfgang P; Loi, Maria Cecilia; Kieselbach, Thomas; Bochtler, Matthias; Piano, Dario
2013-12-01
Photosystem II has been purified from a transplastomic strain of Nicotiana tabacum according to two different protocols. Using the procedure described in Piano et al. (Photosynth Res 106:221-226, 2010) it was possible to isolate highly active PSII composed of monomers and dimers but depleted in their PsbS protein content. A "milder" procedure than the protocol reported by Fey et al. (Biochim Biophys Acta 1777:1501-1509, 2008) led to almost exclusively monomeric PSII complexes which in part still bind the PsbS protein. This finding might support a role for PSII monomers in higher plants.
Bacterial and fungal DNA extraction from blood samples: automated protocols.
Lorenz, Michael G; Disqué, Claudia; Mühl, Helge
2015-01-01
Automation in DNA isolation is a necessity for routine practice employing molecular diagnosis of infectious agents. To this end, the development of automated systems for the molecular diagnosis of microorganisms directly in blood samples is at its beginning. Important characteristics of systems demanded for routine use include high recovery of microbial DNA, DNA-free containment for the reduction of DNA contamination from exogenous sources, DNA-free reagents and consumables, ideally a walkaway system, and economical pricing of the equipment and consumables. Such full automation of DNA extraction evaluated and in use for sepsis diagnostics is yet not available. Here, we present protocols for the semiautomated isolation of microbial DNA from blood culture and low- and high-volume blood samples. The protocols include a manual pretreatment step followed by automated extraction and purification of microbial DNA.
Blomeyer, Christoph A; Bazil, Jason N; Stowe, David F; Dash, Ranjan K; Camara, Amadou K S
2016-06-01
The manner in which mitochondria take up and store Ca(2+) remains highly debated. Recent experimental and computational evidence has suggested the presence of at least two modes of Ca(2+) uptake and a complex Ca(2+) sequestration mechanism in mitochondria. But how Mg(2+) regulates these different modes of Ca(2+) uptake as well as mitochondrial Ca(2+) sequestration is not known. In this study, we investigated two different ways by which mitochondria take up and sequester Ca(2+) by using two different protocols. Isolated guinea pig cardiac mitochondria were exposed to varying concentrations of CaCl2 in the presence or absence of MgCl2. In the first protocol, A, CaCl2 was added to the respiration buffer containing isolated mitochondria, whereas in the second protocol, B, mitochondria were added to the respiration buffer with CaCl2 already present. Protocol A resulted first in a fast transitory uptake followed by a slow gradual uptake. In contrast, protocol B only revealed a slow and gradual Ca(2+) uptake, which was approximately 40 % of the slow uptake rate observed in protocol A. These two types of Ca(2+) uptake modes were differentially modulated by extra-matrix Mg(2+). That is, Mg(2+) markedly inhibited the slow mode of Ca(2+) uptake in both protocols in a concentration-dependent manner, but not the fast mode of uptake exhibited in protocol A. Mg(2+) also inhibited Na(+)-dependent Ca(2+) extrusion. The general Ca(2+) binding properties of the mitochondrial Ca(2+) sequestration system were reaffirmed and shown to be independent of the mode of Ca(2+) uptake, i.e. through the fast or slow mode of uptake. In addition, extra-matrix Mg(2+) hindered Ca(2+) sequestration. Our results indicate that mitochondria exhibit different modes of Ca(2+) uptake depending on the nature of exposure to extra-matrix Ca(2+), which are differentially sensitive to Mg(2+). The implications of these findings in cardiomyocytes are discussed.
MPH-M, AODV-M and DSR-M Performance Evaluation under Jamming Attacks.
Del-Valle-Soto, Carolina; Mex-Perera, Carlos; Monroy, Raul; Nolazco-Flores, Juan A
2017-07-05
In this work, we present the design of a mitigation scheme for jamming attacks integrated to the routing protocols MPH, AODV, and DSR. The resulting protocols are named MPH-M (Multi-Parent Hierarchical - Modified), AODV-M (Ad hoc On Demand Distance Vector - Modified), and DSR-M (Dynamic Source Routing - Modified). For the mitigation algorithm, if the detection algorithm running locally in each node produces a positive result then the node is isolated; second, the routing protocol adapts their paths avoiding the isolated nodes. We evaluated how jamming attacks affect different metrics for all these modified protocols. The metrics we employ to detect jamming attack are number of packet retransmissions, number of CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance) retries while waiting for an idle channel and the energy wasted by the node. The metrics to evaluate the performance of the modified routing protocols are the throughput and resilience of the system and the energy used by the nodes. We evaluated all the modified protocols when the attacker position was set near, middle and far of the collector node. The results of our evaluation show that performance for MPH-M is much better than AODV-M and DSR-M. For example, the node energy for MPH-M is 138.13% better than AODV-M and 126.07% better than DSR-M. Moreover, we also find that MPH-M benefits much more of the mitigation scheme than AODV-M and DSR-M. For example, the node energy consumption is 34.61% lower for MPH-M and only 3.92% and 3.42% for AODV-M and DSR-M, respectively. On throughput, the MPH protocol presents a packet reception efficiency at the collector node of 16.4% on to AODV and DSR when there is no mitigation mechanism. Moreover, MPH-M has an efficiency greater than 7.7% with respect to AODV-M and DSR-M when there is a mitigation scheme. In addition, we have that with the mitigation mechanism AODV-M and DSR-M do not present noticeable modification. However, MPH-M improves its efficiency by 8.4%. We also measure the resilience of these algorithms from the average packet re-transmissions perspective, and we find that MPH-M has around a 15% lower change rate than AODV-M and DSR-M. The MPH-M recovery time is 5 s faster than AODV-M and 2 s faster than DSR-M.
MPH-M, AODV-M and DSR-M Performance Evaluation under Jamming Attacks
Del-Valle-Soto, Carolina
2017-01-01
In this work, we present the design of a mitigation scheme for jamming attacks integrated to the routing protocols MPH, AODV, and DSR. The resulting protocols are named MPH-M (Multi-Parent Hierarchical - Modified), AODV-M (Ad hoc On Demand Distance Vector - Modified), and DSR-M (Dynamic Source Routing - Modified). For the mitigation algorithm, if the detection algorithm running locally in each node produces a positive result then the node is isolated; second, the routing protocol adapts their paths avoiding the isolated nodes. We evaluated how jamming attacks affect different metrics for all these modified protocols. The metrics we employ to detect jamming attack are number of packet retransmissions, number of CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance) retries while waiting for an idle channel and the energy wasted by the node. The metrics to evaluate the performance of the modified routing protocols are the throughput and resilience of the system and the energy used by the nodes. We evaluated all the modified protocols when the attacker position was set near, middle and far of the collector node. The results of our evaluation show that performance for MPH-M is much better than AODV-M and DSR-M. For example, the node energy for MPH-M is 138.13% better than AODV-M and 126.07% better than DSR-M. Moreover, we also find that MPH-M benefits much more of the mitigation scheme than AODV-M and DSR-M. For example, the node energy consumption is 34.61% lower for MPH-M and only 3.92% and 3.42% for AODV-M and DSR-M, respectively. On throughput, the MPH protocol presents a packet reception efficiency at the collector node of 16.4% on to AODV and DSR when there is no mitigation mechanism. Moreover, MPH-M has an efficiency greater than 7.7% with respect to AODV-M and DSR-M when there is a mitigation scheme. In addition, we have that with the mitigation mechanism AODV-M and DSR-M do not present noticeable modification. However, MPH-M improves its efficiency by 8.4%. We also measure the resilience of these algorithms from the average packet re-transmissions perspective, and we find that MPH-M has around a 15% lower change rate than AODV-M and DSR-M. The MPH-M recovery time is 5 s faster than AODV-M and 2 s faster than DSR-M. PMID:28678180
Assessment of metabolic stability using the rainbow trout (Oncorhynchus mykiss) liver S9 fraction
Standard protocols are given for assessing metabolic stability in rainbow trout using the liver S9 fraction. These protocols describe the isolation of S9 fractions from trout livers, evaluation of metabolic stability using a substrate depletion approach, and expression of the res...
Castro, Claudia; González, Liliana; Rozo, Juan Carlos; Puerto, Gloria; Ribón, Wellman
2009-12-01
Manipulating Mycobacterium tuberculosis clinical specimens and cultures represents a risk factor for laboratory personnel. One of the processes that requires high concentrations of microorganisms is DNA extraction for molecular procedures. Pulmonary tuberculosis cases have occurred among professionals in charge of molecular procedures that require manipulation of massive quantities of microorganisms. This has prompted research studies on biosafety aspects of extraction protocols; however, as yet, no consensus has been reached regarding risks associated with the process. The biosafety was evaluated for the DNA extraction protocol of van Soolingen, et al. 2002 by determining M. tuberculosis viability at each process stage. Eight hundred eighty cultures were grown from 220 M. tuberculosis clinical isolates that had been processed through the first three DNA extraction stages. Molecular identifications of positive cultures used a PCR isolation of a fragment of the heat shock protein PRA-hsp65 and examination of its restriction enzyme profile (spoligotyping). Growth was seen in one culture with one of the procedures used. The molecular characterization did not correspond to the initially analyzed isolate, and therefore was deduced to be the product of a cross-contamination. The DNA extraction protocol, as described by van Soolingen, et al. 2002 and as implemented at the Instituto Nacional de Salud, was established to be safe for laboratory personnel as well as for the environment.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jaing, Crystal; Vergez, Lisa; Hinckley, Aubree
2011-06-21
The objective of this project is to provide DHS a comprehensive evaluation of the current genomic technologies including genotyping, Taqman PCR, multiple locus variable tandem repeat analysis (MLVA), microarray and high-throughput DNA sequencing in the analysis of biothreat agents from complex environmental samples. As the result of a different DHS project, we have selected for and isolated a large number of ciprofloxacin resistant B. anthracis Sterne isolates. These isolates vary in the concentrations of ciprofloxacin that they can tolerate, suggesting multiple mutations in the samples. In collaboration with University of Houston, Eureka Genomics and Oak Ridge National Laboratory, we analyzedmore » the ciprofloxacin resistant B. anthracis Sterne isolates by microarray hybridization, Illumina and Roche 454 sequencing to understand the error rates and sensitivity of the different methods. The report provides an assessment of the results and a complete set of all protocols used and all data generated along with information to interpret the protocols and data sets.« less
[Protocols for the diagnostic verification of lymph node toxoplasmosis].
Carosi, G; Ghezzi, L G; Filice, G; Maccabruni, A; Parisi, A; Carnevale, G
1983-05-31
The protocol we have fixed for the diagnosis of lymphonodal toxoplasmosis includes a precise succession of tests: 1) specific repeated serological tests (I.H.A.T., I.F.A.T., IgM--I.F.A.T. on total serum and on pure IgM fraction); 2) lymphonodal biopsy for histological examination and biological test (isolation procedure in mouse). We have evaluated the effectiveness of our protocol in 20 cases that we observed during 1980.
Pott, Alexander; Kraft, Christoph; Stephan, Tilman; Petscher, Kerstin; Rottbauer, Wolfgang; Dahme, Tillman
2018-03-15
The optimal freeze duration in cryoballoon pulmonary vein isolation (PVI) is unknown. The 3rd generation cryoballoon facilitates observation of the time-to-isolation (TTI) and thereby enables individualized cryoenergy titration. To evaluate the efficacy of an individualized freeze duration we compared the clinical outcome of patients treated with a TTI-guided ablation protocol to the outcome of patients treated with a fixed ablation protocol. We compared 100 patients treated with the 3rd generation cryoballoon applying a TTI-based protocol (TTI group) to 100 patients treated by a fixed freeze protocol (fixed group). In the fixed group a 240s freeze cycle was followed by a 240s bonus freeze after acute PV isolation. In the TTI group freeze duration was 180s if TTI was ≥30s and reduced to only 120s, if TTI was <30s. In case of a TTI >60s a 180s bonus freeze was applied. Freedom from atrial arrhythmia recurrence off class I/III antiarrhythmic drugs after one year was not different between the TTI group (73.6%) and the fixed group (75.7%; p=0.75). Mean procedure duration was 85.8±27.3min in the TTI group compared to 115.7±27.1min in the fixed group (p<0.001). Mean fluoroscopy time was 17.5±6.6min in the TTI group and 22.5±9.8min in the fixed group (p<0.001). TTI-guided cryoenergy titration leads to reduced procedure duration and fluoroscopy time and appears to be as effective as a fixed ablation strategy. A single 2-minute freeze seems to be sufficient in case of short TTI. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.
Lichtenberg, Sven; Magosch, Petra; Habermeyer, Peter
2012-11-01
The aim of the study was to evaluate differences of clinical results between the latissimus-dorsi transfer combined with teres-major transfer (G1) and the isolated latissimus-dorsi transfer (G2) for the treatment of massive irreparable postero-superior rotator cuff tears. We performed the combined latissimus-dorsi/teres-major transfer in 17 patients at a mean age of 57 years. Furthermore, 17 patients at a mean age of 61 years were treated using the isolated latissimus-dorsi transfer. Both groups were followed-up clinically, radiologically, and with surface electromyography using the same study protocol. The Constant score (CS) improved significantly from 48.3 points pre-op to 69.5 points post-op after a follow-up of 58 months in G1. The active range of motion improved in G1 sig. for flexion (124° pre-op, 166.5° post-op) and for abduction (117° pre-op, 163° post-op). The CS improved significantly from 45.1 points pre-op to 74.2 points post-op after a follow-up of 51 months in G2. The flexion and abduction increased significantly from 133.3° pre-op to 176° post-op, resp. from 113.3° pre-op to 173° post-op. The comparison of both surgical techniques showed a significant better active flexion and abduction for G2. Both techniques achieved good functional results but the isolated latissimus-dorsi transfer produced a better active abduction and flexion, whereas the combined latissmus-dorsi/teres-major transfer achieved an increase in abduction strength. In contrast to the combined latissimus-dorsi/teres-major transfer, a progression of cuff tear arthropathy was not observed with the isolated latissimus-dorsi transfer. Copyright © 2012 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.
Generation of genome-modified Drosophila cell lines using SwAP.
Franz, Alexandra; Brunner, Erich; Basler, Konrad
2017-10-02
The ease of generating genetically modified animals and cell lines has been markedly increased by the recent development of the versatile CRISPR/Cas9 tool. However, while the isolation of isogenic cell populations is usually straightforward for mammalian cell lines, the generation of clonal Drosophila cell lines has remained a longstanding challenge, hampered by the difficulty of getting Drosophila cells to grow at low densities. Here, we describe a highly efficient workflow to generate clonal Cas9-engineered Drosophila cell lines using a combination of cell pools, limiting dilution in conditioned medium and PCR with allele-specific primers, enabling the efficient selection of a clonal cell line with a suitable mutation profile. We validate the protocol by documenting the isolation, selection and verification of eight independently Cas9-edited armadillo mutant Drosophila cell lines. Our method provides a powerful and simple workflow that improves the utility of Drosophila cells for genetic studies with CRISPR/Cas9.
Trauma Quality Improvement: Reducing Triage Errors by Automating the Level Assignment Process.
Stonko, David P; O Neill, Dillon C; Dennis, Bradley M; Smith, Melissa; Gray, Jeffrey; Guillamondegui, Oscar D
2018-04-12
Trauma patients are triaged by the severity of their injury or need for intervention while en route to the trauma center according to trauma activation protocols that are institution specific. Significant research has been aimed at improving these protocols in order to optimize patient outcomes while striving for efficiency in care. However, it is known that patients are often undertriaged or overtriaged because protocol adherence remains imperfect. The goal of this quality improvement (QI) project was to improve this adherence, and thereby reduce the triage error. It was conducted as part of the formal undergraduate medical education curriculum at this institution. A QI team was assembled and baseline data were collected, then 2 Plan-Do-Study-Act (PDSA) cycles were implemented sequentially. During the first cycle, a novel web tool was developed and implemented in order to automate the level assignment process (it takes EMS-provided data and automatically determines the level); the tool was based on the existing trauma activation protocol. The second PDSA cycle focused on improving triage accuracy in isolated, less than 10% total body surface area burns, which we identified to be a point of common error. Traumas were reviewed and tabulated at the end of each PDSA cycle, and triage accuracy was followed with a run chart. This study was performed at Vanderbilt University Medical Center and Medical School, which has a large level 1 trauma center covering over 75,000 square miles, and which sees urban, suburban, and rural trauma. The baseline assessment period and each PDSA cycle lasted 2 weeks. During this time, all activated, adult, direct traumas were reviewed. There were 180 patients during the baseline period, 189 after the first test of change, and 150 after the second test of change. All were included in analysis. Of 180 patients, 30 were inappropriately triaged during baseline analysis (3 undertriaged and 27 overtriaged) versus 16 of 189 (3 undertriaged and 13 overtriaged) following implementation of the web tool (p = 0.017 for combined errors). Overtriage dropped further from baseline to 10/150 after the second test of change (p = 0.005). The total number of triaged patients dropped from 92.3/week to 75.5/week after the second test of change. There was no statistically significant change in the undertriage rate. The combination of web tool implementation and protocol refinement decreased the combined triage error rate by over 50% (from 16.7%-7.9%). We developed and tested a web tool that improved triage accuracy, and provided a sustainable method to enact future quality improvement. This web tool and QI framework would be easily expandable to other hospitals. Copyright © 2018 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.
Darabi, Shahram; Tiraihi, Taki; Delshad, AliReza; Sadeghizadeh, Majid; Taheri, Taher; Hassoun, Hayder K
2017-04-01
Creatine was reported to induce bone marrow stromal cells (BMSC) into GABAergic neuron-like cells (GNLC). In a previous study, creatine was used as a single inducer for BMSC into GNLC with low yield. In this study, BMSC-derived neurospheres (NS) have been used in generating GABAergic phenotype. The BMSC were isolated from adult rats and used in generating neurospheres and used for producing neural stem cells (NSC). A combination of all-trans-retinoic acid (RA), the ciliary neurotrophic factor (CNTF), and creatine was used in order to improve the yield of GNLC. We also used other protocols for the transdifferentiation including RA alone; RA and creatine; RA and CNTF; and RA, CNTF, and creatine. The BMSC, NSC, and GNLC were characterized by specific markers. The activity of the GNLC was evaluated using FM1-43. The isolated BMSC expressed Oct4, fibronectin, and CD44. The NS were immunoreactive to nestin and SOX2, the NSC were immunoreactive to nestin, NF68 and NF160, while the GNLC were immunoreactive to GAD1/2, VGAT, GABA, and synaptophysin. Oct4 and c-MYC, pluripotency genes, were expressed in the BMSC, while SOX2 and c-MYC were expressed in the NSC. The activity of GNLC indicates that the synaptic vesicles were released upon stimulation. The conclusion is that the combination of RA, CNTF, and creatine induced differentiation of neurosphere-derived NSC into GNLC within 1 week. This protocol gives higher yield than the other protocols used in this study. The mechanism of induction was clearly associated with several differential pluripotent genes.
Giménez, Montserrat; Sanfeliu, Isabel; Sierra, Montserrat; Dopico, Eva; Juncosa, Teresa; Andreu, Antonia; Lite, Josep; Guardià, Cèlia; Sánchez, Ferran; Bosch, Jordi
2015-01-01
To study the evolution of the incidence of early-onset neonatal sepsis (EOS) by Streptococcus agalactiae in the area of Barcelona and to analyze failure of compliance with the prevention protocol. A retrospective review was carried out on EOS cases in 8 Health-Care Centers in the Barcelona area between 2004 and 2010. Forty-nine newborns from 48 mothers were diagnosed with EOS. The incidence was 0.29‰ living newborns (0.18-0.47‰), with no significant differences in the fluctuations along the 7 years. The mortality rate was 8.16%. In 68.5% cases the maternal colonization studies were negative, and in 21% these studies were not performed. No risk factors were detected in 58.3% of pregnant women, and 22.9% of births were premature. In 58% of cases intra-partum antibiotic prophylaxis was not administered because it was not indicated, and in 42% due to failure to follow the protocol (3 strains were resistant to erythromycin). Resistance to clindamycin was 33.3%. The Streptococcus agalactiae serotypes more frequently isolated were iii, v, and ia. No significant changes were detected in the incidence of Streptococcus agalactiae EOS in the 7 years of the study. The increased sensitivity of screening methods with the use of molecular techniques, the performance of susceptibility testing of strains isolated from pregnant women, and the improvement of communication between Health-Care Centers, can contribute to a better implementation of the protocol, as well as to reduce the incidence of EOS. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.
Growth in liquid or solid media.
Elbing, K L; Brent, R
2001-05-01
This appendix presents basic procedures for growing overnight (and larger) cultures, monitoring growth, and titering and isolating bacterial cultures by serial dilution. In addition, protocols are provided for isolating single colonies by streaking and spreading a plate. Replica plating and strain storage/retrieval is also detailed.
Alba, Annia; Marcet, Ricardo; Otero, Oscar; Hernández, Hilda M; Figueredo, Mabel; Sarracent, Jorge
2016-02-01
Purification of immunoglobulin M (IgM) antibodies could be challenging, and is often characterized by the optimization of the purification protocol to best suit the particular features of the molecule. Here, two different schemes were compared to purify, from ascites, the 1E4 IgM monoclonal antibody (mAb) previously raised against the stage of redia of the trematode Fasciola hepatica. This immunoglobulin is used as capture antibody in an immunoenzymatic assay to detect parasite ongoing infection in its intermediate hosts. The first purification protocol of the 1E4 mAb involved two chromatographic steps: an affinity chromatography on a Concanavalin A matrix followed by size exclusion chromatography. An immunoaffinity chromatography was selected as the second protocol for one-step purification of the antibody using the crude extract of adult parasites coupled to a commercial matrix. Immunoreactivity of the fractions during purification schemes was assessed by indirect immunoenzymatic assays against the crude extract of F. hepatica rediae, while purity was estimated by protein electrophoresis. Losses on the recovery of the antibody isolated by the first purification protocol occurred due to protein precipitation during the concentration of the sample and to low resolution of the size exclusion molecular chromatography step regarding this particular immunoglobulin. The immunoaffinity chromatography using F. hepatica antigens as ligands proved to be the most suitable protocol yielding a pure and immunoreactive antibody. The purification protocols used are discussed regarding efficiency and difficulties.
Microfluidic, marker-free isolation of circulating tumor cells from blood samples
Karabacak, Nezihi Murat; Spuhler, Philipp S; Fachin, Fabio; Lim, Eugene J; Pai, Vincent; Ozkumur, Emre; Martel, Joseph M; Kojic, Nikola; Smith, Kyle; Chen, Pin-i; Yang, Jennifer; Hwang, Henry; Morgan, Bailey; Trautwein, Julie; Barber, Thomas A; Stott, Shannon L; Maheswaran, Shyamala; Kapur, Ravi; Haber, Daniel A; Toner, Mehmet
2014-01-01
The ability to isolate and analyze rare circulating tumor cells (CTCs) has the potential to further our understanding of cancer metastasis and enhance the care of cancer patients. In this protocol, we describe the procedure for isolating rare CTCs from blood samples by using tumor antigen–independent microfluidic CTC-iChip technology. The CTC-iChip uses deterministic lateral displacement, inertial focusing and magnetophoresis to sort up to 107 cells/s. By using two-stage magnetophoresis and depletion antibodies against leukocytes, we achieve 3.8-log depletion of white blood cells and a 97% yield of rare cells with a sample processing rate of 8 ml of whole blood/h. The CTC-iChip is compatible with standard cytopathological and RNA-based characterization methods. This protocol describes device production, assembly, blood sample preparation, system setup and the CTC isolation process. Sorting 8 ml of blood sample requires 2 h including setup time, and chip production requires 2–5 d. PMID:24577360
Molecular beacon-enabled purification of living cells by targeting cell type-specific mRNAs.
Wile, Brian M; Ban, Kiwon; Yoon, Young-Sup; Bao, Gang
2014-10-01
Molecular beacons (MBs) are dual-labeled oligonucleotides that fluoresce only in the presence of complementary mRNA. The use of MBs to target specific mRNAs allows sorting of specific cells from a mixed cell population. In contrast to existing approaches that are limited by available surface markers or selectable metabolic characteristics, the MB-based method enables the isolation of a wide variety of cells. For example, the ability to purify specific cell types derived from pluripotent stem cells (PSCs) is important for basic research and therapeutics. In addition to providing a general protocol for MB design, validation and nucleofection into cells, we describe how to isolate a specific cell population from differentiating PSCs. By using this protocol, we have successfully isolated cardiomyocytes differentiated from mouse or human PSCs (hPSCs) with ∼ 97% purity, as confirmed by electrophysiology and immunocytochemistry. After designing MBs, their ordering and validation requires 2 weeks, and the isolation process requires 3 h.
Methods for the extraction and RNA profiling of exosomes
Zeringer, Emily; Li, Mu; Barta, Tim; Schageman, Jeoffrey; Pedersen, Ketil Winther; Neurauter, Axl; Magdaleno, Susan; Setterquist, Robert; Vlassov, Alexander V
2013-01-01
AIM: To develop protocols for isolation of exosomes and characterization of their RNA content. METHODS: Exosomes were extracted from HeLa cell culture media and human blood serum using the Total exosome isolation (from cell culture media) reagent, and Total exosome isolation (from serum) reagent respectively. Identity and purity of the exosomes was confirmed by Nanosight® analysis, electron microscopy, and Western blots for CD63 marker. Exosomal RNA cargo was recovered with the Total exosome RNA and protein isolation kit. Finally, RNA was profiled using Bioanalyzer and quantitative reverse transcription-polymerase chain reaction (qRT-PCR) methodology. RESULTS: Here we describe a novel approach for robust and scalable isolation of exosomes from cell culture media and serum, with subsequent isolation and analysis of RNA residing within these vesicles. The isolation procedure is completed in a fraction of the time, compared to the current standard protocols utilizing ultracentrifugation, and allows to recover fully intact exosomes in higher yields. Exosomes were found to contain a very diverse RNA cargo, primarily short sequences 20-200 nt (such as miRNA and fragments of mRNA), however longer RNA species were detected as well, including full-length 18S and 28S rRNA. CONCLUSION: We have successfully developed a set of reagents and a workflow allowing fast and efficient extraction of exosomes, followed by isolation of RNA and its analysis by qRT-PCR and other techniques. PMID:25237619
Mouse Liver Mitochondria Isolation, Size Fractionation, and Real-time MOMP Measurement.
Renault, Thibaud T; Luna-Vargas, Mark P A; Chipuk, Jerry E
2016-08-05
The mitochondrial pathway of apoptosis involves a complex interplay between dozens of proteins and lipids, and is also dependent on the shape and size of mitochondria. The use of cellular models in past studies has not been ideal for investigating how the complex multi-factor interplay regulates the molecular mechanisms of mitochondrial outer membrane permeabilization (MOMP). Isolated systems have proven to be a paradigm to deconstruct MOMP into individual steps and to study the behavior of each subset of MOMP regulators. In particular, isolated mitochondria are key to in vitro studies of the BCL-2 family proteins, a complex family of pro-survival and pro-apoptotic proteins that directly control the mitochondrial pathway of apoptosis (Renault et al ., 2013). In this protocol, we describe three complementary procedures for investigating in real-time the effects of MOMP regulators using isolated mitochondria. The first procedure is "Liver mitochondria isolation" in which the liver is dissected from mice to obtain mitochondria. "Mitochondria labeling with JC-1 and size fractionation" is the second procedure that describes a method to label, fractionate by size and standardize subpopulations of mitochondria. Finally, the "Real-time MOMP measurements" protocol allows to follow MOMP in real-time on isolated mitochondria. The aforementioned procedures were used to determine in vitro the role of mitochondrial membrane shape at the level of isolated cells and isolated mitochondria (Renault et al ., 2015).
Pandis, Nikolaos; Fleming, Padhraig S; Koletsi, Despina; Hopewell, Sally
2016-12-07
It is important that planned randomised trials are justified and placed in the context of the available evidence. The SPIRIT guidelines for reporting clinical trial protocols recommend that a recent and relevant systematic review should be included. The aim of this study was to assess the use of the existing evidence in order to justify trial conduct. Protocols of randomised trials published over a 1-month period (December 2015) indexed in PubMed were obtained. Data on trial characteristics relating to location, design, funding, conflict of interest and type of evidence included for trial justification was extracted in duplicate and independently by two investigators. The frequency of citation of previous research including relevant systematic reviews and randomised trials was assessed. Overall, 101 protocols for RCTs were identified. Most proposed trials were parallel-group (n = 74; 73.3%). Reference to an earlier systematic review with additional randomised trials was found in 9.9% (n = 10) of protocols and without additional trials in 30.7% (n = 31), while reference was made to randomised trials in isolation in 21.8% (n = 22). Explicit justification for the proposed randomised trial on the basis of being the first to address the research question was made in 17.8% (n = 18) of protocols. A randomised controlled trial was not cited in 10.9% (95% CI: 5.6, 18.7) (n = 11), while in 8.9% (95% CI: 4.2, 16.2) (n = 9) of the protocols a systematic review was cited but did not inform trial design. A relatively high percentage of protocols of randomised trials involves prior citation of randomised trials, systematic reviews or both. However, improvements are required to ensure that it is explicit that clinical trials are justified and shaped by contemporary best evidence.
La Scola, Bernard; Raoult, Didier
2009-11-25
With long delays observed between sampling and availability of results, the usefulness of blood cultures in the context of emergency infectious diseases has recently been questioned. Among methods that allow quicker bacterial identification from growing colonies, matrix-assisted laser desorption ionisation time-of-flight (MALDI-TOF) mass spectrometry was demonstrated to accurately identify bacteria routinely isolated in a clinical biology laboratory. In order to speed up the identification process, in the present work we attempted bacterial identification directly from blood culture bottles detected positive by the automate. We prospectively analysed routine MALDI-TOF identification of bacteria detected in blood culture by two different protocols involving successive centrifugations and then lysis by trifluoroacetic acid or formic acid. Of the 562 blood culture broths detected as positive by the automate and containing one bacterial species, 370 (66%) were correctly identified. Changing the protocol from trifluoroacetic acid to formic acid improved identification of Staphylococci, and overall correct identification increased from 59% to 76%. Lack of identification was observed mostly with viridans streptococci, and only one false positive was observed. In the 22 positive blood culture broths that contained two or more different species, only one of the species was identified in 18 samples, no species were identified in two samples and false species identifications were obtained in two cases. The positive predictive value of bacterial identification using this procedure was 99.2%. MALDI-TOF MS is an efficient method for direct routine identification of bacterial isolates in blood culture, with the exception of polymicrobial samples and viridans streptococci. It may replace routine identification performed on colonies, provided improvement for the specificity of blood culture broths growing viridans streptococci is obtained in the near future.
Sandoval-Sierra, Jose Vladimir; Diéguez-Uribeondo, Javier
2015-01-01
The description, identification and classification of organisms are the pillar in biodiversity and evolutionary studies. The fungal-like organism Saprolegnia contains important animal pathogens. However, its taxonomy is weak, making it difficult to perform further studies. This problem mainly arises from the unavailability of suitable holotypes. We propose a standardized protocol for describing Saprolegnia spp. that includes good cultural practices and proper holotype preservation. In order to illustrate this new proposal, we describe two species, Saprolegnia aenigmatica sp. nov. and Saprolegnia racemosa sp. nov., based on the recently described molecular operational taxonomic units (MOTUs), phylogenetic relationships, and the analyses of morphological features. We show that they belong to two different MOTUs that are grouped into two sister clades. Morphologically, we find that S. racemosa exhibits a species-specific character, i.e., aggrupation of oogonia in racemes, while S. aenigmatica does not have any specific characters. Analyses of a combined set of characters, i.e., length and breadth of sporangia, length/breadth ratio (l/b) of oogonia, cyst and oospore diameter, and the number of oospores per oogomium, allow distinguishing these two species. To improve Saprolegnia taxonomy, we propose to incorporate into the protologue: (i) several isolates of the new species; (ii) the rDNA sequences to compare them to data-bases of Saprolegnia sequences of reference; (iii) a phylogenetic analysis to check relationships with other species; (iv) to preserve holotypes in absolute ethanol and to include lyophilized material from holotype; and (v) the ex-type as a pure culture from single-spore isolates stored in at least two different collections.
Exogenous Attention Enables Perceptual Learning
Szpiro, Sarit F. A.; Carrasco, Marisa
2015-01-01
Practice can improve visual perception, and these improvements are considered to be a form of brain plasticity. Training-induced learning is time-consuming and requires hundreds of trials across multiple days. The process of learning acquisition is understudied. Can learning acquisition be potentiated by manipulating visual attentional cues? We developed a protocol in which we used task-irrelevant cues for between-groups manipulation of attention during training. We found that training with exogenous attention can enable the acquisition of learning. Remarkably, this learning was maintained even when observers were subsequently tested under neutral conditions, which indicates that a change in perception was involved. Our study is the first to isolate the effects of exogenous attention and to demonstrate its efficacy to enable learning. We propose that exogenous attention boosts perceptual learning by enhancing stimulus encoding. PMID:26502745
Influence of freezing down to 77.15 K on structure and antioxidant power of some proteins
NASA Astrophysics Data System (ADS)
Rozanova, S. L.; Narozhnyi, S. V.; Nardid, O. A.
2017-06-01
The purpose of the present work was to investigate influence of different freeze-thawing protocols on structure and antioxidant properties of isolated proteins. In our experiments we have studied human serum albumin, human hemoglobin and cytochrome C derived from equine heart frozen down to 77.15 K with 1-2 deg/min and 300 deg/min rate with following thawing on a water bath at 293.15 K. Native proteins were assumed as a control. Influence of freeze-thawing protocols on protein structure was investigated using spectrophotometric and fluorescent assays. Antioxidant activities of isolated proteins were estimated by their ability to reduce ABTS+ radical. It has been established that unfolding derived from freeze-thawing exposure leads to protein antioxidant activity increasing while decreasing of such an activity may be connected with macromolecule aggregation. Character of freeze-thawing influence on antioxidant activity of proteins depends on molecule structure peculiarities and freezing protocols.
Clinically Practical Magnetic Resonance Protocol for Improved Specificity in Breast Cancer Diagnosis
2007-06-01
Protocol for Improved Specificity in Breast Cancer Diagnosis PRINCIPAL INVESTIGATOR: Luminita Alina Tudorica, Ph.D. CONTRACTING...TITLE AND SUBTITLE 5a. CONTRACT NUMBER Clinically Practical Magnetic Resonance Protocol for Improved Specificity in Breast Cancer Diagnosis 5b... breast cancer study in a clinical setting. This study aims to improve specificity of breast cancer detection by using a combined MRI/MRS protocol. In
Britto, Ingrid Schwach Werneck; Sananes, Nicolas; Olutoye, Oluyinka O; Cass, Darrell L; Sangi-Haghpeykar, Haleh; Lee, Timothy C; Cassady, Christopher I; Mehollin-Ray, Amy; Welty, Stephen; Fernandes, Caraciolo; Belfort, Michael A; Lee, Wesley; Ruano, Rodrigo
2015-10-01
The purpose of this study was to evaluate the impact of standardization of the lung-to-head ratio measurements in isolated congenital diaphragmatic hernia on prediction of neonatal outcomes and reproducibility. We conducted a retrospective cohort study of 77 cases of isolated congenital diaphragmatic hernia managed in a single center between 2004 and 2012. We compared lung-to-head ratio measurements that were performed prospectively in our institution without standardization to standardized measurements performed according to a defined protocol. The standardized lung-to-head ratio measurements were statistically more accurate than the nonstandardized measurements for predicting neonatal mortality (area under the receiver operating characteristic curve, 0.85 versus 0.732; P = .003). After standardization, there were no statistical differences in accuracy between measurements regardless of whether we considered observed-to-expected values (P > .05). Standardization of the lung-to-head ratio did not improve prediction of the need for extracorporeal membrane oxygenation (P> .05). Both intraoperator and interoperator reproducibility were good for the standardized lung-to-head ratio (intraclass correlation coefficient, 0.98 [95% confidence interval, 0.97-0.99]; bias, 0.02 [limits of agreement, -0.11 to +0.15], respectively). Standardization of lung-to-head ratio measurements improves prediction of neonatal outcomes. Further studies are needed to confirm these results and to assess the utility of standardization of other prognostic parameters.
Isolation and culture of neural crest cells from embryonic murine neural tube.
Pfaltzgraff, Elise R; Mundell, Nathan A; Labosky, Patricia A
2012-06-02
The embryonic neural crest (NC) is a multipotent progenitor population that originates at the dorsal aspect of the neural tube, undergoes an epithelial to mesenchymal transition (EMT) and migrates throughout the embryo, giving rise to diverse cell types. NC also has the unique ability to influence the differentiation and maturation of target organs. When explanted in vitro, NC progenitors undergo self-renewal, migrate and differentiate into a variety of tissue types including neurons, glia, smooth muscle cells, cartilage and bone. NC multipotency was first described from explants of the avian neural tube. In vitro isolation of NC cells facilitates the study of NC dynamics including proliferation, migration, and multipotency. Further work in the avian and rat systems demonstrated that explanted NC cells retain their NC potential when transplanted back into the embryo. Because these inherent cellular properties are preserved in explanted NC progenitors, the neural tube explant assay provides an attractive option for studying the NC in vitro. To attain a better understanding of the mammalian NC, many methods have been employed to isolate NC populations. NC-derived progenitors can be cultured from post-migratory locations in both the embryo and adult to study the dynamics of post-migratory NC progenitors, however isolation of NC progenitors as they emigrate from the neural tube provides optimal preservation of NC cell potential and migratory properties. Some protocols employ fluorescence activated cell sorting (FACS) to isolate a NC population enriched for particular progenitors. However, when starting with early stage embryos, cell numbers adequate for analyses are difficult to obtain with FACS, complicating the isolation of early NC populations from individual embryos. Here, we describe an approach that does not rely on FACS and results in an approximately 96% pure NC population based on a Wnt1-Cre activated lineage reporter. The method presented here is adapted from protocols optimized for the culture of rat NC. The advantages of this protocol compared to previous methods are that 1) the cells are not grown on a feeder layer, 2) FACS is not required to obtain a relatively pure NC population, 3) premigratory NC cells are isolated and 4) results are easily quantified. Furthermore, this protocol can be used for isolation of NC from any mutant mouse model, facilitating the study of NC characteristics with different genetic manipulations. The limitation of this approach is that the NC is removed from the context of the embryo, which is known to influence the survival, migration and differentiation of the NC.
Cryptanalysis and Improvement of the Semi-quantum Secret Sharing Protocol
NASA Astrophysics Data System (ADS)
Gao, Xiang; Zhang, Shibin; Chang, Yan
2017-08-01
Recently, Xie et al. Int. J. Theor. Phys. 54, 3819-3824, (2015) proposed a Semi-quantum secret sharing protocol (SQSS). Yin et al. Int. J. Theor. Phys. 55: 4027-4035, (2016) pointed out that this protocol suffers from the intercept-resend attack. Yin et al. also proposed an improved protocol. However, we find out that Yin et al.'s paper has some problems, we analyze Yin et al.'s paper, then proposed the improved semi-quantum secret sharing protocol. Our protocol is more secure and efficient, most importantly, our protocol satisfies the condition of semi-quantum.
2014-01-01
Background Economically, Leuconostoc lactis is one of the most important species in the genus Leuconostoc. It plays an important role in the food industry including the production of dextrans and bacteriocins. Currently, traditional molecular typing approaches for characterisation of this species at the isolate level are either unavailable or are not sufficiently reliable for practical use. Multilocus sequence typing (MLST) is a robust and reliable method for characterising bacterial and fungal species at the molecular level. In this study, a novel MLST protocol was developed for 50 L. lactis isolates from Mongolia and China. Results Sequences from eight targeted genes (groEL, carB, recA, pheS, murC, pyrG, rpoB and uvrC) were obtained. Sequence analysis indicated 20 different sequence types (STs), with 13 of them being represented by a single isolate. Phylogenetic analysis based on the sequences of eight MLST loci indicated that the isolates belonged to two major groups, A (34 isolates) and B (16 isolates). Linkage disequilibrium analyses indicated that recombination occurred at a low frequency in L. lactis, indicating a clonal population structure. Split-decomposition analysis indicated that intraspecies recombination played a role in generating genotypic diversity amongst isolates. Conclusions Our results indicated that MLST is a valuable tool for typing L. lactis isolates that can be used for further monitoring of evolutionary changes and population genetics. PMID:24912963
Multi-Hop Teleportation of an Unknown Qubit State Based on W States
NASA Astrophysics Data System (ADS)
Zhou, Xiang-Zhen; Yu, Xu-Tao; Zhang, Zai-Chen
2018-04-01
Quantum teleportation is important in quantum communication networks. Considering that quantum state information is also transmitted between two distant nodes, intermediated nodes are employed and two multi-hop teleportation protocols based on W state are proposed. One is hop-by-hop teleportation protocol and the other is the improved multi-hop teleportation protocol with centralized unitary transformation. In hop-by-hop protocol, the transmitted quantum state needs to be recovered at every node on the route. In improved multi-hop teleportation protocol with centralized unitary transformation, intermediate nodes need not to recover the transmitted quantum state. Compared to the hop-by-hop protocol, the improved protocol can reduce the transmission delay and improve the transmission efficiency.
Dhanya, K; Kizhakkayil, Jaleel; Syamkumar, S; Sasikumar, B
2007-10-01
Black pepper is an important medicinal spice traded internationally. The extraction of high quality genomic DNA for PCR amplification from dried black pepper is challenging because of the presence of the exceptionally large amount of oxidized polyphenolic compounds, polysaccharides and other secondary metabolites. Here we report a modified hexadecyl trimethyl ammonium bromide (CTAB) protocol by incorporating potassium acetate and a final PEG precipitation step to isolate PCR amplifiable genomic DNA from dried and powdered berries of black pepper. The protocol has trade implication as it will help in the PCR characterization of traded black peppers from different countries.
A model-based executive for commanding robot teams
NASA Technical Reports Server (NTRS)
Barrett, Anthony
2005-01-01
The paper presents a way to robustly command a system of systems as a single entity. Instead of modeling each component system in isolation and then manually crafting interaction protocols, this approach starts with a model of the collective population as a single system. By compiling the model into separate elements for each component system and utilizing a teamwork model for coordination, it circumvents the complexities of manually crafting robust interaction protocols. The resulting systems are both globally responsive by virtue of a team oriented interaction model and locally responsive by virtue of a distributed approach to model-based fault detection, isolation, and recovery.
Isolation of zymogen granules from rat pancreas.
Rindler, Michael J
2006-01-01
This unit describes methods for preparing zymogen granules from rat pancreas. Zymogen granules are storage organelles in pancreatic acinar cells containing digestive enzymes that are released into the pancreatic duct. The protocols in this unit take advantage of the large size (up to 1 microm diameter) and high density (>1.20 g/cm(3) on sucrose gradients) of the granules as compared to other cellular organelles. They use a combination of differential sedimentation and density gradient separation to accomplish the purification. Similar procedures can be used to isolate zymogen granules from mouse pancreas and canine pancreas. A protocol for preparing zymogen granules from dog pancreas is also included.
Pfeiffer, Elisa; Zeilinger, Katrin; Seehofer, Daniel; Damm, Georg
2016-01-01
Beside parenchymal hepatocytes, the liver consists of non-parenchymal cells (NPC) namely Kupffer cells (KC), liver endothelial cells (LEC) and hepatic Stellate cells (HSC). Two-dimensional (2D) culture of primary human hepatocyte (PHH) is still considered as the "gold standard" for in vitro testing of drug metabolism and hepatotoxicity. It is well-known that the 2D monoculture of PHH suffers from dedifferentiation and loss of function. Recently it was shown that hepatic NPC play a central role in liver (patho-) physiology and the maintenance of PHH functions. Current research focuses on the reconstruction of in vivo tissue architecture by 3D- and co-culture models to overcome the limitations of 2D monocultures. Previously we published a method to isolate human liver cells and investigated the suitability of these cells for their use in cell cultures in Experimental Biology and Medicine1. Based on the broad interest in this technique the aim of this article was to provide a more detailed protocol for the liver cell isolation process including a video, which will allow an easy reproduction of this technique. Human liver cells were isolated from human liver tissue samples of surgical interventions by a two-step EGTA/collagenase P perfusion technique. PHH were separated from the NPC by an initial centrifugation at 50 x g. Density gradient centrifugation steps were used for removal of dead cells. Individual liver cell populations were isolated from the enriched NPC fraction using specific cell properties and cell sorting procedures. Beside the PHH isolation we were able to separate KC, LEC and HSC for further cultivation. Taken together, the presented protocol allows the isolation of PHH and NPC in high quality and quantity from one donor tissue sample. The access to purified liver cell populations could allow the creation of in vivo like human liver models. PMID:27077489
Kegel, Victoria; Deharde, Daniela; Pfeiffer, Elisa; Zeilinger, Katrin; Seehofer, Daniel; Damm, Georg
2016-03-30
Beside parenchymal hepatocytes, the liver consists of non-parenchymal cells (NPC) namely Kupffer cells (KC), liver endothelial cells (LEC) and hepatic Stellate cells (HSC). Two-dimensional (2D) culture of primary human hepatocyte (PHH) is still considered as the "gold standard" for in vitro testing of drug metabolism and hepatotoxicity. It is well-known that the 2D monoculture of PHH suffers from dedifferentiation and loss of function. Recently it was shown that hepatic NPC play a central role in liver (patho-) physiology and the maintenance of PHH functions. Current research focuses on the reconstruction of in vivo tissue architecture by 3D- and co-culture models to overcome the limitations of 2D monocultures. Previously we published a method to isolate human liver cells and investigated the suitability of these cells for their use in cell cultures in Experimental Biology and Medicine(1). Based on the broad interest in this technique the aim of this article was to provide a more detailed protocol for the liver cell isolation process including a video, which will allow an easy reproduction of this technique. Human liver cells were isolated from human liver tissue samples of surgical interventions by a two-step EGTA/collagenase P perfusion technique. PHH were separated from the NPC by an initial centrifugation at 50 x g. Density gradient centrifugation steps were used for removal of dead cells. Individual liver cell populations were isolated from the enriched NPC fraction using specific cell properties and cell sorting procedures. Beside the PHH isolation we were able to separate KC, LEC and HSC for further cultivation. Taken together, the presented protocol allows the isolation of PHH and NPC in high quality and quantity from one donor tissue sample. The access to purified liver cell populations could allow the creation of in vivo like human liver models.
Mazzarella, Tonia; Cambiaghi, Valeria; Rizzo, Nathalie; Pilla, Lorenzo; Parolini, Danilo; Orsenigo, Elena; Colucci, Annalisa; Modorati, Giulio; Doglioni, Claudio; Parmiani, Giorgio; Maccalli, Cristina
2012-08-01
Tumor-infiltrating lymphocytes (TILs) have been successfully used for adoptive cell transfer (ACT) immunotherapy; however, due to their scarce availability, this therapy is possible for a limited fraction of cutaneous melanoma patients. We assessed whether an effective protocol for ex vivo T-cell expansion from peripheral blood mononuclear cells (PBMCs), suitable for ACT of both cutaneous and ocular melanoma patients, could be identified. PBMCs from both cutaneous and ocular melanoma patients were stimulated in vitro with autologous, irradiated melanoma cells (mixed lymphocyte tumor cell culture; MLTCs) in the presence of IL-2 and IL-15 followed by the rapid expansion protocol (REP). The functional activity of these T lymphocytes was characterized and compared with that of TILs. In addition, the immune infiltration in vivo of ocular melanoma lesions was analyzed. An efficient in vitro MLTC expansion of melanoma reactive T cells was achieved from all PBMC's samples obtained in 7 cutaneous and ocular metastatic melanoma patients. Large numbers of melanoma-specific T cells could be obtained when the REP protocol was applied to these MLTCs. Most MLTCs were enriched in non-terminally differentiated T(EM) cells homogeneously expressing co-stimulatory molecules (e.g., NKG2D, CD28, CD134, CD137). A similar pattern of anti-tumor activity, in association with a more variable expression of co-stimulatory molecules, was detected on short-term in vitro cultured TILs isolated from the same patients. In these ocular melanoma patients, we observed an immune infiltrate with suppressive characteristics and a low rate of ex vivo growing TILs (28.5% of our cases). Our MLTC protocol overcomes this limitation, allowing the isolation of T lymphocytes with effector functions even in these patients. Thus, anti-tumor circulating PBMC-derived T cells could be efficiently isolated from melanoma patients by our novel ex vivo enrichment protocol. This protocol appears suitable for ACT studies of cutaneous and ocular melanoma patients.
Pig Pancreas Anatomy: Implications for Pancreas Procurement, Preservation, and Islet Isolation
Ferrer, Joana; Scott, William E; Weegman, Bradley P; Suszynski, Thomas M; Sutherland, David E R; Hering, Bernhard J; Papas, Klearchos K
2009-01-01
Background Islet transplantation is emerging as a treatment option for selected patients with type 1 diabetes. The limited human islet supply from cadavers and poor islet yield and quality remain substantial impediments to progress in the field. Use of porcine islets holds great promise for large-scale application of islet transplantation. Consistent isolation of porcine islets is dependent on advances in pancreas procurement and preservation, and islet isolation requiring detailed knowledge of the porcine pancreatic anatomy. The primary aim of this study was to describe the vascular and ductal anatomy of the porcine pancreas in order to guide and improve organ preservation and enzyme perfusion. Methods Pancreata were removed by en bloc viscerectomy from 65 female Landrace pigs. Results 15% of organs exhibited inconsistent vascular branching from the celiac trunk. All organs had uniform patterns of branching at the superior mesenteric artery. The superior and inferior mesenteric veins (IMV) merged to become the portal vein in all but one case in which the IMV drained into the splenic vein. 97% of pancreata had three lobes: duodenal (DL), connecting (CL), and splenic (SL); 39% demonstrated ductal communication between the CL and the other two lobes; 50% had ductal communication only between the CL and DL; and 11% presented other types of ductal delineation. Conclusions Accounting for the variations in vascular and ductal anatomy, as detailed in this study, will facilitate development of protocols for preservation, optimal enzyme administration, and pancreas distention and digestion, and ultimately lead to substantial improvements in isolation outcomes. PMID:19077881
An, Diaoguo; Zheng, Qi; Luo, Qiaoling; Ma, Pengtao; Zhang, Hongxia; Li, Lihui; Han, Fangpu; Xu, Hongxing; Xu, Yunfeng; Zhang, Xiaotian; Zhou, Yilin
2015-01-01
Rye (Secale cereale L.) possesses many valuable genes that can be used for improving disease resistance, yield and environment adaptation of wheat (Triticum aestivum L.). However, the documented resistance stocks derived from rye is faced severe challenge due to the variation of virulent isolates in the pathogen populations. Therefore, it is necessary to develop desirable germplasm and search for novel resistance gene sources against constantly accumulated variation of the virulent isolates. In the present study, a new wheat-rye line designated as WR49-1 was produced through distant hybridization and chromosome engineering protocols between common wheat cultivar Xiaoyan 6 and rye cultivar German White. Using sequential GISH (genomic in situ hybridization), mc-FISH (multicolor fluorescence in situ hybridization), mc-GISH (multicolor GISH) and EST (expressed sequence tag)-based marker analysis, WR49-1 was proved to be a new wheat-rye 6R disomic addition line. As expected, WR49-1 showed high levels of resistance to wheat powdery mildew (Blumeria graminis f. sp. tritici, Bgt) pathogens prevalent in China at the adult growth stage and 19 of 23 Bgt isolates tested at the seedling stage. According to its reaction pattern to different Bgt isolates, WR49-1 may possess new resistance gene(s) for powdery mildew, which differed from the documented powdery mildew gene, including Pm20 on chromosome arm 6RL of rye. Additionally, WR49-1 was cytologically stable, had improved agronomic characteristics and therefore could serve as an important bridge for wheat breeding and chromosome engineering. PMID:26237413
Gaston, Kirk W; Limbach, Patrick A
2014-01-01
The analysis of ribonucleic acids (RNA) by mass spectrometry has been a valuable analytical approach for more than 25 years. In fact, mass spectrometry has become a method of choice for the analysis of modified nucleosides from RNA isolated out of biological samples. This review summarizes recent progress that has been made in both nucleoside and oligonucleotide mass spectral analysis. Applications of mass spectrometry in the identification, characterization and quantification of modified nucleosides are discussed. At the oligonucleotide level, advances in modern mass spectrometry approaches combined with the standard RNA modification mapping protocol enable the characterization of RNAs of varying lengths ranging from low molecular weight short interfering RNAs (siRNAs) to the extremely large 23 S rRNAs. New variations and improvements to this protocol are reviewed, including top-down strategies, as these developments now enable qualitative and quantitative measurements of RNA modification patterns in a variety of biological systems. PMID:25616408
Gaston, Kirk W; Limbach, Patrick A
2014-01-01
The analysis of ribonucleic acids (RNA) by mass spectrometry has been a valuable analytical approach for more than 25 years. In fact, mass spectrometry has become a method of choice for the analysis of modified nucleosides from RNA isolated out of biological samples. This review summarizes recent progress that has been made in both nucleoside and oligonucleotide mass spectral analysis. Applications of mass spectrometry in the identification, characterization and quantification of modified nucleosides are discussed. At the oligonucleotide level, advances in modern mass spectrometry approaches combined with the standard RNA modification mapping protocol enable the characterization of RNAs of varying lengths ranging from low molecular weight short interfering RNAs (siRNAs) to the extremely large 23 S rRNAs. New variations and improvements to this protocol are reviewed, including top-down strategies, as these developments now enable qualitative and quantitative measurements of RNA modification patterns in a variety of biological systems.
Fumière, O; Marien, A; Fernández Pierna, J A; Baeten, V; Berben, G
2010-08-01
At present, European legislation prohibits totally the use of processed animal proteins in feed for all farmed animals (Commission Regulation (EC) No. 1234/2003-extended feed ban). A softening of the feed ban for non-ruminants would nevertheless be considered if alternative methods could be used to gain more information concerning the species origin of processed animal proteins than that which can be provided by classical optical microscopy. This would allow control provisions such as the ban of feeding animals with proteins from the same species or intra-species recycling (Regulation (EC) No. 1774/2002). Two promising alternative methods, near-infrared microscopy (NIRM) and real-time polymerase chain reaction (PCR), were combined to authenticate, at the species level, the presence of animal particles. The paper describes the improvements of the real-time PCR method made to the DNA extraction protocol, allowing five PCR analyses to be performed with the DNA extracted from a single particle.
Brancaccio, Rosario N; Robitaille, Alexis; Dutta, Sankhadeep; Cuenin, Cyrille; Santare, Daiga; Skenders, Girts; Leja, Marcis; Fischer, Nicole; Giuliano, Anna R; Rollison, Dana E; Grundhoff, Adam; Tommasino, Massimo; Gheit, Tarik
2018-05-07
With the advent of new molecular tools, the discovery of new papillomaviruses (PVs) has accelerated during the past decade, enabling the expansion of knowledge about the viral populations that inhabit the human body. Human PVs (HPVs) are etiologically linked to benign or malignant lesions of the skin and mucosa. The detection of HPV types can vary widely, depending mainly on the methodology and the quality of the biological sample. Next-generation sequencing is one of the most powerful tools, enabling the discovery of novel viruses in a wide range of biological material. Here, we report a novel protocol for the detection of known and unknown HPV types in human skin and oral gargle samples using improved PCR protocols combined with next-generation sequencing. We identified 105 putative new PV types in addition to 296 known types, thus providing important information about the viral distribution in the oral cavity and skin. Copyright © 2018. Published by Elsevier Inc.
Development of a Novel Listeria Enrichment Broth for the Isolation of Pathogenic Listeria.
Liu, Dongxin; Wang, Yan; Wang, Yi; Zhang, Lu; Luo, Lijuan; Liu, Kai; Ye, Changyun
2017-10-01
Listeriosis, the disease caused by pathogenic Listeria species, can present severe symptoms in susceptible people. The goal of this study was to develop a novel enrichment broth, Listeria allose enrichment broth (LAEB), to improve isolation of Listeria monocytogenes and Listeria ivanovii from samples through incorporating a specific carbohydrate and reducing inhibitor concentrations. Other coexisting bacteria, particularly Listeria innocua, can interfere with the isolation of pathogenic Listeria in such ways as overgrowth of L. innocua and the generation of inhibitory metabolites. The incorporation of allose into the novel LAEB was effective for slowing the growth of L. innocua and other nontarget microorganisms. We determined that 35°C and pH 7.0 under aerobic conditions are optimal for Listeria growth in this medium. The novelty of the use of LAEB is the single enrichment procedure at 35°C for 24 h, obviating the need for a secondary enrichment medium. In 50 simulated samples, the sensitivity of the LAEB method (86%) was higher than that of the International Organization for Standardization (EN ISO) method (70%). In 142 naturally contaminated samples tested, the isolation rate for pathogenic Listeria with the LAEB method was 26.0% (37 of 142 samples), which was significantly higher than the 17.6% (25 of 142 samples) for the EN ISO method. Higher isolation rates and a quicker and easier protocol make the novel LAEB method an appropriate alternative for the isolation of pathogenic Listeria.
Isolating Lysosomes from Rat Liver.
Pryor, Paul R
2016-04-01
This protocol describes the generation of a fraction enriched in lysosomes from rat liver. The lysosomes are rapidly isolated using density-gradient centrifugation with gradient media that retain the osmolarity of the lysosomes such that they are functional and can be used in in vitro assays. © 2016 Cold Spring Harbor Laboratory Press.
Evaluation of isolation methods for bacterial RNA quantitation in Dickeya dadantii
USDA-ARS?s Scientific Manuscript database
Dickeya dadantii is a difficult source for RNA of a sufficient quality for real-time qRT-PCR analysis of gene expression. Three RNA isolation methods were evaluated for their ability to produce high-quality RNA from this bacterium. Bacterial lysis with Trizol using standard protocols consistently ga...
Peptidome characterization and bioactivity analysis of donkey milk.
Piovesana, Susy; Capriotti, Anna Laura; Cavaliere, Chiara; La Barbera, Giorgia; Samperi, Roberto; Zenezini Chiozzi, Riccardo; Laganà, Aldo
2015-04-24
Donkey milk is an interesting commercial product for its nutritional values, which make it the most suitable mammalian milk for human consumption, and for the bioactivity associated with it and derivative products. To further mine the characterization of donkey milk, an extensive peptidomic study was performed. Two peptide purification strategies were compared to remove native proteins and lipids and enrich the peptide fraction. In one case the whole protein content was precipitated by organic solvent using cold acetone. In the other one the precipitation of the most abundant milk proteins, caseins, was performed under acidic conditions by acetic acid at pH4.6, instead. The procedures were compared and proved to be partially complementary. Considered together they provided 1330 peptide identifications for donkey milk, mainly coming from the most abundant proteins in milk. The bioactivity of the isolated peptides was also investigated, both by angiotensin-converting-enzyme inhibitory and antioxidant activity assays and by bioinformatics, proving that the isolated peptides did have the tested biological activities. The rationale behind this study is that peptides in food matrices often play an important biological role and, despite the extensive study of the protein composition of different samples, they remain poorly characterized. In fact, in a typical shotgun proteomics study endogenous peptides are not properly characterized. In proteomics workflows one limiting point is the isolation process: if it is specific for the purification of proteins, it often comprises a precipitation step which aims at isolating pure protein pellets and remove unwonted interferent compounds. In this way endogenous peptides, which are not effectively precipitated as well as proteins, are removed too and not analyzed at the end of the process. Moreover, endogenous peptides do often originate from precursor proteins, but in phenomena which are independent of the shotgun digestion protocol, thus they can be obtained from cleavage specificities other than trypsin's, which is the main proteolytic enzyme employed in proteomic experiments. For this reason, in the end, database search will not be effective for identification of these peptides, thus the need to provide different workflows for peptide analysis. In the work presented in this paper this issue is considered for the first time for the analysis of the peptides isolated in donkey milk samples, which have been chosen for its nutritional interest. This study provides additional knowledge on this milk, already characterized by traditional proteomics studies and peptidomic studies after simulated digestion. This type of study is not just a description of the naturally occurring peptidome of a sample, but also represents a starting point to discover and characterize those naturally occurring peptides responsible for the observed bioactivities of biological samples, as in the case of donkey milk, which would remain uncharacterized by other approaches. In this paper an analytical protocol was described for the efficient isolation and purification of peptides in donkey milk, assessing the effect of the purification protocol on the final identifications. Purified peptide samples were also checked to empirically elucidate any ACE inhibitory or antioxidant activity. Finally, the peptidomic results were also further mined by a bioinformatic-driven approach for bioactive peptide identification in the donkey milk samples. In our opinion, the main strengths of this study are related to the improved analytical workflow (either as purification protocol comparison or analytical platform development) which provides a high number of identified peptides, for which the biological significance as potential bioactive peptides has also been investigated. Copyright © 2015 Elsevier B.V. All rights reserved.
Kupčík, Rudolf; Zelená, Miroslava; Řehulka, Pavel; Bílková, Zuzana; Česlová, Lenka
2016-02-01
Hydrophobins are small proteins that play a role in a number of processes during the filamentous fungi growth and development. These proteins are characterized by the self-assembly of their molecules into an amphipathic membrane at hydrophilic-hydrophobic interfaces. Isolation and purification of hydrophobins generally present a challenge in their analysis. Hydrophobin SC3 from Schizophyllum commune was selected as a representative of class I hydrophobins in this work. A novel procedure for selective and effective isolation of hydrophobin SC3 based on solid-phase extraction with polytetrafluoroethylene microparticles loaded in a small self-made microcolumn is reported. The tailored binding of hydrophobins to polytetrafluoroethylene followed by harsh elution conditions resulted in a highly specific isolation of hydrophobin SC3 from the model mixture of ten proteins. The presented isolation protocol can have a positive impact on the analysis and utilization of these proteins including all class I hydrophobins. Hydrophobin SC3 was further subjected to reduction of its highly stable disulfide bonds and to chymotryptic digestion followed by mass spectrometric analysis. The isolation and digestion protocols presented in this work make the analysis of these highly hydrophobic and compact proteins possible. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Chaudhry, Shehzad Ashraf; Naqvi, Husnain; Shon, Taeshik; Sher, Muhammad; Farash, Mohammad Sabzinejad
2015-06-01
Telecare medical information systems (TMIS) provides rapid and convenient health care services remotely. Efficient authentication is a prerequisite to guarantee the security and privacy of patients in TMIS. Authentication is used to verify the legality of the patients and TMIS server during remote access. Very recently Islam et al. (J. Med. Syst. 38(10):135, 2014) proposed a two factor authentication protocol for TMIS using elliptic curve cryptography (ECC) to improve Xu et al.'s (J. Med. Syst. 38(1):9994, 2014) protocol. They claimed their improved protocol to be efficient and provides all security requirements. However our analysis reveals that Islam et al.'s protocol suffers from user impersonation and server impersonation attacks. Furthermore we proposed an enhanced protocol. The proposed protocol while delivering all the virtues of Islam et al.'s protocol resists all known attacks.
Early therapy-related myeloid sarcoma and deletion of 9q22.32 to q31.1.
Brickler, Molly M; Basel, Donald G; Gheorghe, Gabriela; Margolis, David M; Kelly, Michael E; Ehrhardt, Matthew J
2014-09-01
Survival following childhood neuroblastoma is improving with low rates of secondary myeloid neoplasms. We describe a 13-month-old male with intermediate risk neuroblastoma who developed an isolated scalp therapy-related myeloid sarcoma (t-MS). Developmental delays and two distinct malignancies prompted constitutional evaluation. Chromosomal microarray identified a 7.3 Mb deletion of 9q22.32 to 9q31.1. He remains in remission 11 months following hematopoietic cell transplant. Unusual presentations of rare diseases necessitate a multidisciplinary approach and adaptation of standardized protocols to accommodate increased risks imposed by genetic variants. © 2014 Wiley Periodicals, Inc.
Remote access to medical specialists: home care interactive patient management system
NASA Astrophysics Data System (ADS)
Martin, Peter J.; Draghic, Nicole; Wiesmann, William P.
1999-07-01
Diabetes management involves constant care and rigorous compliance. Glucose control is often difficult to maintain and onset of complications further compound health care needs. Status can be further hampered by geographic isolation from immediate medical infrastructures. The Home Care Interactive Patient Management System is an experimental telemedicine program that could improve chronic illness management through Internet-based applications. The goal of the system is to provide a customized, integrated approach to diabetes management to supplement and coordinate physician protocol while supporting routine patient activity, by supplying a set of customized automated services including health data collection, transmission, analysis and decision support.
Hao, Qiang; Chen, Xiao-Lin; Ma, Li; Wang, Tong-Tong; Hu, Yue; Zhao, Yuan-Li
2018-01-01
In this study, we successfully established a stable method for the isolation of endothelial cells (ECs) from human cerebral arteriovenous malformation (cAVM) tissues. Despite human cAVM tissues having a minor population of ECs, they play an important role in the manifestation and development of cAVM as well as in hemorrhagic stroke and thrombogenesis. To characterize and understand the biology of ECs in human cAVM (cAVM-ECs), methods for the isolation and purification of these cells are necessary. We have developed this method to reliably obtain pure populations of ECs from cAVMs. To obtain pure cell populations, cAVM tissues were mechanically and enzymatically digested and the resulting single cAVM-ECs suspensions were then labeled with antibodies of specific cell antigens and selected by flow cytometry. Purified ECs were detected using specific makers of ECs by immunostaining and used to study different cellular mechanisms. Compared to the different methods of isolating ECs from tissues, we could isolate ECs from cAVMs confidently, and the numbers of cAVM-ECs harvested were almost similar to the amounts present in vessel components. In addition to optimizing the protocol for isolation of ECs from human cAVM tissues, the protocol could also be applied to isolate ECs from other human neurovascular-diseased tissues. Depending on the tissues, the whole procedure could be completed in about 20 days.
Mouse Liver Mitochondria Isolation, Size Fractionation, and Real-time MOMP Measurement
Renault, Thibaud T.; Luna-Vargas, Mark P.A.; Chipuk, Jerry E.
2016-01-01
The mitochondrial pathway of apoptosis involves a complex interplay between dozens of proteins and lipids, and is also dependent on the shape and size of mitochondria. The use of cellular models in past studies has not been ideal for investigating how the complex multi-factor interplay regulates the molecular mechanisms of mitochondrial outer membrane permeabilization (MOMP). Isolated systems have proven to be a paradigm to deconstruct MOMP into individual steps and to study the behavior of each subset of MOMP regulators. In particular, isolated mitochondria are key to in vitro studies of the BCL-2 family proteins, a complex family of pro-survival and pro-apoptotic proteins that directly control the mitochondrial pathway of apoptosis (Renault et al., 2013). In this protocol, we describe three complementary procedures for investigating in real-time the effects of MOMP regulators using isolated mitochondria. The first procedure is “Liver mitochondria isolation” in which the liver is dissected from mice to obtain mitochondria. “Mitochondria labeling with JC-1 and size fractionation” is the second procedure that describes a method to label, fractionate by size and standardize subpopulations of mitochondria. Finally, the “Real-time MOMP measurements” protocol allows to follow MOMP in real-time on isolated mitochondria. The aforementioned procedures were used to determine in vitro the role of mitochondrial membrane shape at the level of isolated cells and isolated mitochondria (Renault et al., 2015). PMID:28093578
Adeniji, Johnson Adekunle; Faleye, Temitope Oluwasegun Cephas
2014-10-01
There has been under-reporting of nonpolio enterovirus species Cs (NPESCs) in Nigeria despite the fact that most isolates recovered from the Nigerian vaccine derived poliovirus serotype 2 (VDPV2) outbreak were recombinants with nonstructural region of NPESC origin. It has been suggested that cell lines included in enterovirus isolation protocols might account for this phenomenon and this study examined this suggestion. Fifteen environmental samples concentrated previously and analysed using L20B and RD cell lines as part of the poliovirus environmental surveillance (ES) program in Nigeria were randomly selected and inoculated into two cell lines (MCF-7 and LLC-MK2). Isolates were identified as enteroviruses and species C members using different RT-PCR assays, culture in L20B cell line and sequencing of partial VP1. Forty-eight (48) isolates were recovered from the 15 samples, 47 (97.9%) of which were enteroviruses. Of the enteroviruses, 32 (68.1%) belonged to enterovirus species C (EC) of which 19 (40.4%) were polioviruses and 13 (27.7%) were NPESC members. All 13 NPESC isolates were recovered on MCF-7. Results of the study show that NPESCs are circulating in Nigeria and their under-reporting was due to the combination of cell lines used for enterovirus isolation in previous reports. Copyright © 2014 Elsevier B.V. All rights reserved.
Hogan, Marie C.; Johnson, Kenneth L.; Zenka, Roman M.; Charlesworth, M. Cristine; Madden, Benjamin J.; Mahoney, Doug W.; Oberg, Ann L.; Huang, Bing Q.; Nesbitt, Lisa L.; Bakeberg, Jason L.; Bergen, H. Robert; Ward, Christopher J.
2014-01-01
Urinary exosome-like vesicles (ELVs) are a heterogenous mixture (diameter 40–200nm) containing vesicles shed from all segments of the nephron including glomerular podocytes. Contamination with Tamm Horsfall protein (THP) oligomers has hampered their isolation and proteomic analysis. Here we improved ELV isolation protocols employing density centrifugation to remove THP and albumin, and isolated a glomerular membranous vesicle (GMV) enriched subfraction from 7 individuals identifying 1830 proteins and in 3 patients with glomerular disease identifying 5657 unique proteins. The GMV fraction was composed of podocin/podocalyxin positive irregularly shaped membranous vesicles and podocin/podocalyxin negative classical exosomes. Ingenuity pathway analysis identified integrin, actin cytoskeleton and RhoGDI signaling in the top three canonical represented signaling pathways and 19 other proteins associated with inherited glomerular diseases. The GMVs are of podocyte origin and the density gradient technique allowed isolation in a reproducible manner. We show many nephrotic syndrome proteins, proteases and complement proteins involved in glomerular disease are in GMVs and some were shed in the disease state (nephrin, TRPC6 and INF2 and PLA2R). We calculated sample sizes required to identify new glomerular disease biomarkers, expand the ELV proteome and provide a reference proteome in a database that may prove useful in the search for biomarkers of glomerular disease. PMID:24196483
ERIC Educational Resources Information Center
Britos, Leticia; Goyenola, Guillermo; Orono, Silvia Umpierrez
2004-01-01
An extremely simple, inexpensive, and safe method is presented, which emulates nucleic acids isolation and electrophoretic analysis as performed in a research environment, in the context of a secondary school hands-on activity. The protocol is amenable to an interdisciplinary approach, taking into consideration the electrical and chemical…
Lemos, M; Souza, C S F; da Costa, S C Gonçalves; Souto-Padrón, T; D'Agosto, M
2013-02-01
The purpose of this study was to verify the in vitro development of Trypanosoma sp. isolated from Leptodactylus ocellatus frogs under a new protocol using a biphasic medium composed of Novy, McNeal, and Nicolle (NNN) blood agar medium as a solid phase and liver infusion, brain heart infusion, and tryptose (LIBHIT) medium as a liquid phase. Blood forms, collected by cardiac puncture or after the maceration of different organs, were inoculated in culture tubes containing the biphasic medium composed by NNN and LIBHIT. Trypanosomes were observed 4 days postinoculation; most bloodstream trypomastigotes had differentiated into epimastigotes and amastigotes by this time. Trypomastigotes were again observed in older cultures (7 days). Parasites were successfully subcultured for 8 mo in this medium and successfully cryopreserved. The present study provides a new protocol medium for the isolation and culture of anuran trypanosomes.
Eavesdropping on the improved three-party quantum secret sharing protocol
NASA Astrophysics Data System (ADS)
Gao, Gan
2011-02-01
Lin et al. [Song Lin, Fei Gao, Qiao-yan Wen, Fu-chen Zhu, Opt. Commun. 281 (2008) 4553] pointed out that the multiparty quantum secret sharing protocol [Zhan-jun Zhang, Gan Gao, Xin Wang, Lian-fang Han, Shou-hua Shi, Opt. Commun. 269 (2007) 418] is not secure and proposed an improved three-party quantum secret sharing protocol. In this paper, we study the security of the improved three-party quantum secret sharing protocol and find that it is still not secure. Finally, a further improved three-party quantum secret sharing protocol is proposed.
Saura-Llamas, J; Saturno Hernández, P J; Gaona Ramón, J M; Romero Román, J R; González Barberá, M
1999-11-15
To find the factors that affect the use of clinical protocols in primary care, in the view of primary care team coordinators, and the reasons why they are little followed, and to bring together suggestions for improvement. An opinion study, through a telephone survey. Primary health care. The health centres in Murcia with protocolized activity: 31 at the start of the project. The coordinators and those in charge of nursing, 62 people in all. After a pilot study, a structured telephone survey was carried out, administered by a trained interviewer who posed two open questions: why do you think that the professionals at your centre do not use the existing protocols more often? and: what suggestions would you make to improve the protocols and have them used more? A specialist company did the field-work in June and July 1996. There was a 98% reply rate. To the first question, coordinators thought that low use could be explained by excess demand and lack of time for consultations (33% of all replies), although they also cited other organisational problems in the centre, defects in protocols and lack of training. Those in charge of nursing gave very similar replies, with excess demand (39%) predominating. To the second question, on increasing the use of protocols, coordinators suggested that the protocols needed to be improved (44.8% of replies), and also cited the need for improvements in organisation and on-going training. Very similar answers came from the nursing side, where 43.5% highlighted the need to improve the protocol documents. The coordinators assumed that the clinical protocols were used little and could be improved. In their view the basic reason for their low use is excessive pressure from the patient-load. The key to using them more is improvement in the protocol documents.
Colony-PCR Is a Rapid Method for DNA Amplification of Hyphomycetes
Walch, Georg; Knapp, Maria; Rainer, Georg; Peintner, Ursula
2016-01-01
Fungal pure cultures identified with both classical morphological methods and through barcoding sequences are a basic requirement for reliable reference sequences in public databases. Improved techniques for an accelerated DNA barcode reference library construction will result in considerably improved sequence databases covering a wider taxonomic range. Fast, cheap, and reliable methods for obtaining DNA sequences from fungal isolates are, therefore, a valuable tool for the scientific community. Direct colony PCR was already successfully established for yeasts, but has not been evaluated for a wide range of anamorphic soil fungi up to now, and a direct amplification protocol for hyphomycetes without tissue pre-treatment has not been published so far. Here, we present a colony PCR technique directly from fungal hyphae without previous DNA extraction or other prior manipulation. Seven hundred eighty-eight fungal strains from 48 genera were tested with a success rate of 86%. PCR success varied considerably: DNA of fungi belonging to the genera Cladosporium, Geomyces, Fusarium, and Mortierella could be amplified with high success. DNA of soil-borne yeasts was always successfully amplified. Absidia, Mucor, Trichoderma, and Penicillium isolates had noticeably lower PCR success. PMID:29376929
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huet, Joëlle, E-mail: jhuet@ulb.ac.be; Azarkan, Mohamed; Looze, Yvan
2008-05-01
A chitinase isolated from the latex of the tropical species Carica papaya has been crystallized. The addition of N-acetyl-d-glucosamine to the crystallization solution has improved the diffraction quality resolution of the crystal to 1.8 Å resolution. A chitinase isolated from the latex of the tropical species Carica papaya has been purified to homogeneity and crystallized. This enzyme belongs to glycosyl hydrolase family 19 and exhibits exceptional resistance to proteolysis. The initially observed crystals, which diffracted to a resolution of 2.0 Å, were improved through modification of the crystallization protocol. Well ordered crystals were subsequently obtained using N-acetyl-d-glucosamine, the monomer resultingmore » from the hydrolysis of chitin, as an additive to the crystallization solution. Here, the characterization of a chitinase crystal that belongs to the monoclinic space group P2{sub 1}, with unit-cell parameters a = 69.08, b = 44.79, c = 76.73 Å, β = 95.33° and two molecules per asymmetric unit, is reported. Diffraction data were collected to a resolution of 1.8 Å. Structure refinement is currently in progress.« less
Van Berkel, Megan A; MacDermott, Jennifer; Dungan, Kathleen M; Cook, Charles H; Murphy, Claire V
2017-12-01
Although studies demonstrate techniques to limit hypoglycaemia in critically ill patients, there are limited data supporting methods to improve management of existing hypoglycaemia. Assess the impact and sustainability of a computerised, three tiered, nurse driven protocol for hypoglycaemia treatment. Retrospective pre and post protocol study. Neurosciences and surgical intensive care units at a tertiary academic medical centre. Patients with a hypoglycaemic episode were included during a pre-protocol or post-protocol implementation period. An additional six-month cohort was evaluated to assess sustainability. Fifty-four patients were included for evaluation (35 pre- and 19 post-protocol); 122 patients were included in the sustainability cohort. Hypoglycaemia treatment significantly improved in the post-protocol cohort (20% vs. 52.6%, p=0.014); with additional improvement to 79.5% in the sustainability cohort. Time to follow-up blood glucose was decreased after treatment from 122 [Q1-Q3: 46-242] minutes pre-protocol to 25 [Q1-Q3: 9-48] minutes post protocol (p<0.0001). This reduction was maintained in the sustainability cohort [median of 29min (Q1-Q3: 20-51)]. Implementation of a nurse-driven, three-tiered protocol for treatment of hypoglyacemia significantly improved treatment rates, as well as reduced time to recheck blood glucose measurement. These benefits were sustained during a six-month period after protocol implementation. Copyright © 2017 Elsevier Ltd. All rights reserved.
Langbeen, A; Jorssen, E P A; Fransen, E; Rodriguez, A P A; García, M Chong; Leroy, J L M R; Bols, P E J
2015-10-01
Due to the increased interest in preantral follicular physiology, non-invasive retrieval and morphological classification are crucial. Therefore, this study aimed: (1) to standardize a minimally invasive isolation protocol, applicable to three ruminant species; (2) to morphologically classify preantral follicles upon retrieval; and (3) to describe morphological features of freshly retrieved follicles compared with follicle characteristics using invasive methods. Bovine, caprine and ovine ovarian cortex strips were retrieved from slaughterhouse ovaries and dispersed. This suspension was filtered, centrifuged, re-suspended and transferred to a Petri dish, to which 0.025 mg/ml neutral red (NR) was added to assess the viability of the isolated follicles. Between 59 and 191 follicles per follicle class and per species were collected and classified by light microscopy, based on follicular cell morphology. Subsequently, follicle diameters were measured. The proposed isolation protocol was applicable to all three species and showed a significant, expected increase in diameter with developmental stage. With an average diameter of 37 ± 5 μm for primordial follicles, 47 ± 6.3 μm for primary follicles and 67.1 ± 13.1 μm for secondary follicles, no significant difference in diameter among the three species was observed. Bovine, caprine and ovine follicles (63, 59 and 50% respectively) were graded as viable upon retrieval. Using the same morphological characteristics as determined by invasive techniques [e.g. haematoxylin-eosin (HE) sections], cumulus cell morphology and follicle diameter could be used routinely to classify freshly retrieved follicles. Finally, we applied a mechanical, minimally invasive, follicle isolation protocol and extended it to three ruminant species, yielding viable preantral follicles without compromising further in vitro processing and allowing routine follicle characterization upon retrieval.
Sulaiman, Irshad M; Jacobs, Emily; Segars, Katharine; Simpson, Steven; Kerdahi, Khalil
2016-08-01
Cronobacter sakazakii is an opportunistic human-pathogenic bacterium known to cause acute meningitis and necrotizing enterocolitis in neonates and immunocompromised individuals. This human-pathogenic microorganism has been isolated from a variety of food and environmental samples, and has been also linked to foodborne outbreaks associated with powdered infant formula (PIF). The U.S. Food and Drug Administration have a policy of zero tolerance of these organisms in PIF. Thus, this agency utilizes the presence of these microorganisms as one of the criteria in implementing regulatory actions and assessing adulteration of food products of public health importance. In this study, we recovered two isolates of Cronobacter from the 91 environmental swab samples during an investigation of sporadic case of foodborne illness following conventional microbiological protocols. The isolated typical colonies were identified using VITEK2 and real-time PCR protocols. The recovered Cronobacter isolates were then characterized for species identification by sequencing the 16S rRNA locus. Further, multilocus sequence typing (MLST) was accomplished characterizing seven known C. sakazakii-specific MLST loci (atpD, fusA, glnS, gltB, gyrB, infB, and pps). Results of this study confirmed all of the recovered Cronobacter isolates from the environmental swab samples to be C. sakazakii. The MLST profile matched with the published profile of the complex 31 of C. sakazakii. Thus, rRNA and 7-loci MLST-based sequencing protocols are robust techniques for rapid detection and differentiation of Cronobacter species, and these molecular diagnostic tools can be used in implementing successful surveillance program and in the control and prevention of foodborne illness.
Isolation of Eosinophils from the Lamina Propria of the Murine Small Intestine.
Berek, Claudia; Beller, Alexander; Chu, Van Trung
2016-01-01
Only recently has it become apparent that eosinophils play a crucial role in mucosal immune homeostasis. Although eosinophils are the main cellular component of the lamina propria of the gastrointestinal tract, they have often been overlooked because they express numerous markers, which are normally used to characterize macrophages and/or dendritic cells. To study their function in mucosal immunity, it is important to isolate them with high purity and viability. Here, we describe a protocol to purify eosinophils from the lamina propria of the murine small intestine. The method involves preparation of the small intestine, removal of epithelial cells and digestion of the lamina propria to release eosinophils. A protocol to sort eosinophils is included.
Proroga, Yolande T R; Capuano, Federico; Carullo, Maria Rosaria; La Tela, Immacolata; Capparelli, Rosanna; Barco, Lisa; Pasquale, Vincenzo
2016-01-01
Six hundred fourteen strains of Salmonella enterica were isolated from 16,926 samples of food of animal origin collected in southern Italy from 2003 to 2012. The isolates were identified, serotyped, and challenged against 15 antibiotics according to the protocol defined at national level for veterinary isolates of Salmonella (EnterVet surveillance network). Salmonella serotypes Typhimurium, Hadar, Enteritidis, Derby, and 4,[5],12:i:- were those most frequently isolated. The widest resistances were recorded towards sulfonamides (69 % of the isolates), trimethoprim-sulfamethoxazole (52 % of the isolates), and tetracycline (51 % of the isolates). The rate of multidrug resistance of the isolates decreased significantly from the first 5 years of the study period (82.6 %) to the last 5 years (54.3 %).
Enhanced adipogenic differentiation of bovine bone marrow-derived mesenchymal stem cells
USDA-ARS?s Scientific Manuscript database
Until now, the isolation and characterization of bovine bone marrow-derived mesenchymal stem cells (bBM-MSCs) have not been established, which prompted us to optimize the differentiation protocol for bBM-MSCs. In this study, bBM-MSCs were freshly isolated from three 6-month-old cattle and used for p...
Plaque assay for African swine fever virus on swine macrophages.
Bustos, M J; Nogal, M L; Revilla, Y; Carrascosa, A L
2002-07-01
A plaque assay developed to detect the infection of African Swine Fever Virus on swine macrophages is described. Plaques were generated by all of the virus isolates tested. The method is suitable not only for virus titration but also for the selection of clones in protocols for isolation/purification of recombinant viruses.
Rodrigues, Simone M; Soares, Virgínia L F; de Oliveira, Tahise M; Gesteira, Abelmon S; Otoni, Wagner C; Costa, Marcio G C
2007-11-01
The tropical plant Bixa orellana L. (annatto) produces an array of natural products, including the pigment bixin used in the food and cosmetics industries. In order to understand the biochemical and molecular basis of the biosynthesis of these natural products, a reliable method for isolating high yields of high-quality RNA is required. Here we described a successful and reproducible method for isolation and purification of high-quantity and high-quality RNA from different tissues of annatto. This protocol overcomes the usual problems associated with large amounts of polyphenols, polysaccharides, pigments, and other secondary metabolites that are not easily removed by conventional extraction procedures. Furthermore, the proposed protocol can be easily carried out in any laboratory and it could also be extended to isolate RNA from other plant species showing similar abundance of compounds that interfere with RNA extractions. The yield and quality of the RNA were monitored by spectrophotometric analysis, separation on agarose gel, Reverse Transcription-Polymerase Chain Reaction (RT-PCR), and construction of a cDNA library.
Verma, Poonam; Bansal, Himanshu; Agrawal, Anupama; Leon, Jerry; Sundell, I Birgitta; Koka, Prasad S
Human mesenchymal stem cells from bone marrow (hMSCs) have broad therapeutic potential. These cells can be are readily isolated from bone marrow by their property to adhere to tissue culture treated culture wares. However, the proliferation rates and other properties of the cells gradually change during expansion. This study aims to validate the protocol of isolation and differentiation of hMSCs from bone marrow for therapeutic applications. Sixty ml of bone marrow was extracted from 5 patients and MSCs were isolated. These were characterized by Flow Cytometry, CFU assay and were differentiated into bone, fat cells and neurocytes. The cells were having healthy morphology. These were positive for the markers CD105, CD90 and CD73 and negative for CD45, CD34 and HLA-DR. The cells could differentiate into fat, bone and neural cells. MSCs from the bone marrow were isolated and differentiated. These cells were morphologically healthy and passed CFU assay. The cells exhibited differentiation potential into bone, fat and neural tissue. These cells can be used in therapeutic applications.
Exogenous Attention Enables Perceptual Learning.
Szpiro, Sarit F A; Carrasco, Marisa
2015-12-01
Practice can improve visual perception, and these improvements are considered to be a form of brain plasticity. Training-induced learning is time-consuming and requires hundreds of trials across multiple days. The process of learning acquisition is understudied. Can learning acquisition be potentiated by manipulating visual attentional cues? We developed a protocol in which we used task-irrelevant cues for between-groups manipulation of attention during training. We found that training with exogenous attention can enable the acquisition of learning. Remarkably, this learning was maintained even when observers were subsequently tested under neutral conditions, which indicates that a change in perception was involved. Our study is the first to isolate the effects of exogenous attention and to demonstrate its efficacy to enable learning. We propose that exogenous attention boosts perceptual learning by enhancing stimulus encoding. © The Author(s) 2015.
Role of Investigating Thrombophilic Disorders in Young Stroke
Ng, Kay W. P.; Loh, Pei K.; Sharma, Vijay K.
2011-01-01
Our knowledge about various inherited and acquired causes of thrombophilic disorders has increased significantly during the past decade. Technology for various diagnostic tests for these rare disorders has matched the rapid advances in our understanding about the thrombophilic disorders. Inherited thrombophilic disorders predispose young patients for various venous or arterial thrombotic and thromboembolic episodes. Our understanding has also improved about various gene-gene and gene-environment interactions and their impact on the resultant heterogenous clinical manifestations. We describe various thrombophilic disorders, their diagnostic tests, pathogenic potential in isolation or with other concurrent inherited/acquired defects and possible therapeutic and prophylactic strategies. Better understanding, optimal diagnostic and screening protocols are expected to improve the diagnostic yield and help to reduce morbidity, disability, and mortality in relatively younger patients harbouring these inherited and acquired thrombophilic disorders. PMID:21331344
Rapid pulsed-field gel electrophoresis protocol for subtyping of Streptococcus suis serotype 2.
Luey, Cindy K Y; Chu, Yiu Wai; Cheung, Terence K M; Law, Catherine C P; Chu, Man Yu; Cheung, Danny T L; Kam, Kai Man
2007-03-01
A rapid pulsed-field gel electrophoresis (PFGE) protocol for subtyping of Streptococcus suis serotype 2 was developed and evaluated using 27 clinical isolates from 22 epidemiologically unrelated patients. Results were matched against antibiogram, virulence genotyping and multi locus sequence typing (MLST). PFGE appeared to be the most discriminatory with numerical index of discrimination (D) equal to 0.87.
Hyytiä-Trees, Eija; Smole, Sandra C; Fields, Patricia A; Swaminathan, Bala; Ribot, Efrain M
2006-01-01
Most bacterial genomes contain tandem duplications of short DNA sequences, termed "variable-number tandem repeats" (VNTR). A subtyping method targeting these repeats, multiple-locus VNTR analysis (MLVA), has emerged as a powerful tool for characterization of clonal organisms such as Shiga toxin-producing Escherichia coli O157 (STEC O157). We modified and optimized a recently published MLVA scheme targeting 29 polymorphic VNTR regions of STEC O157 to render it suitable for routine use by public health laboratories that participate in PulseNet, the national and international molecular subtyping network for foodborne disease surveillance. Nine VNTR loci were included in the final protocol. They were amplified in three PCR reactions, after which the PCR products were sized using capillary electrophoresis. Two hundred geographically diverse, sporadic and outbreak- related STEC O157 isolates were characterized by MLVA and the results were compared with data obtained by pulsed-field gel electrophoresis (PFGE) using XbaI macrorestriction of genomic DNA. A total of 139 unique XbaI PFGE patterns and 162 MLVA types were identified. A subset of 100 isolates characterized by both XbaI and BlnI macrorestriction had 62 unique PFGE and MLVA types. Although the clustering of isolates by the two subtyping systems was generally in agreement, some discrepancies were observed. Importantly, MLVA was able to discriminate among some epidemiologically unrelated isolates which were indistinguishable by PFGE. However, among strains from three of the eight outbreaks included in the study, two single locus MLVA variants and one double locus variant were detected among epidemiologically implicated isolates that were indistinguishable by PFGE. Conversely, in three other outbreaks, isolates that were indistinguishable by MLVA displayed multiple PFGE types. An additional more extensive multi-laboratory validation of the MLVA protocol is in progress in order to address critical issues such as establishing epidemiologically relevant interpretation guidelines for the MLVA data.
[Microbiological characterisation of Listeria monocytogenes isolates from human cases in Andalusia].
Lepe, José A; Torres, María José; Liró, Julia; Luque, Rafael; Aznar, Javier
2012-12-01
The aim of this study was to perform a retrospective study by genotyping 154 isolates from human listeriosis cases occurred in the region of Andalusia (southern Spain) in the period 2005-2009. Serotyping was performed for 1 and 4 somatic antigens using commercial Listeria antisera, and by multiplex-PCR serogrouping according to the method described by Doumith et al. (2004). The antimicrobial susceptibility was performed by Epsilon test and interpreted by CLSI criteria. PFGE was performed according to the PulseNet protocol with the ApaI enzyme. The similarity of PFGE profiles was evaluated using the Bionumerics software. The multiplex PCR protocol described by Chen and Knabel (2007) was used for the identification of isolates belonging to L. monocytogenes ECI, ECII, and ECIII epidemic clones. The 154 isolates were grouped into four serotypes: 4b [94 (61%)] strains, 1/2b [30 (19%)] strains, 1/2a [27 (18%)] strains, and 1/2c [3 (2%)] strains, with 100% of susceptibility to ampicillin and cotrimoxazole. A further sixty-two ApaI distinct pulsotypes were recognized. Thirty-seven isolates (24%) showed unique ApaI pulsotypes, and the remaining 117 strains (76%) were assigned to 25 ApaI clusters (60% in clusters of more than two isolates). The EC markers were found in 62 (40.3%) of the L. monocytogenes isolates tested. The ECI marker was present in 43 (46.2%) 4b serotype isolates, ECII in 10 (10.7%) 4b serotype isolates, and ECIII in 9 (33,3%) 1/2a serotype isolates. A large proportion of the human listeriosis cases under investigation could be grouped into molecular subtype clusters, and our cases could be related to international food-borne outbreaks. Copyright © 2011 Elsevier España, S.L. All rights reserved.
Musculoskeletal-induced Nucleation in Altitude Decompression Sickness
NASA Technical Reports Server (NTRS)
Pollock, N. W.; Natoli, M. J.; Conkin, J.; Wessel, J. H., III; Gernhardt, M. L.
2014-01-01
Musculoskeletal activity has the potential to both improve and compromise decompression safety. Exercise enhances inert gas elimination during oxygen breathing prior to decompression (prebreathe), but it may also promote bubble nuclei formation (nucleation), which can lead to gas phase separation and bubble growth and increase the risk of decompression sickness (DCS). The timing, pattern and intensity of musculoskeletal activity and the level of tissue supersaturation may be critical to the net effect. There are limited data available to evaluate cost-benefit relationships. Understanding the relationship is important to improve our understanding of the underlying mechanisms of nucleation in exercise prebreathe protocols and to quantify risk in gravity and microgravity environments. Data gathered during NASA's Prebreathe Reduction Program (PRP) studies combined oxygen prebreathe and exercise followed by low pressure (4.3 psi; altitude equivalent of 30,300 ft [9,235 m]) microgravity simulation to produce two protocols used by astronauts preparing for extravehicular activity. Both the Phase II/CEVIS (cycle ergometer vibration isolation system) and ISLE (in-suit light exercise) trials eliminated ambulation to more closely simulate the microgravity environment. The CEVIS results (35 male, 10 female) serve as control data for this NASA/Duke study to investigate the influence of ambulation exercise on bubble formation and the subsequent risk of DCS.
NASA Astrophysics Data System (ADS)
Livshts, Mikhail A.; Khomyakova, Elena; Evtushenko, Evgeniy G.; Lazarev, Vassili N.; Kulemin, Nikolay A.; Semina, Svetlana E.; Generozov, Edward V.; Govorun, Vadim M.
2015-11-01
Exosomes, small (40-100 nm) extracellular membranous vesicles, attract enormous research interest because they are carriers of disease markers and a prospective delivery system for therapeutic agents. Differential centrifugation, the prevalent method of exosome isolation, frequently produces dissimilar and improper results because of the faulty practice of using a common centrifugation protocol with different rotors. Moreover, as recommended by suppliers, adjusting the centrifugation duration according to rotor K-factors does not work for “fixed-angle” rotors. For both types of rotors - “swinging bucket” and “fixed-angle” - we express the theoretically expected proportion of pelleted vesicles of a given size and the “cut-off” size of completely sedimented vesicles as dependent on the centrifugation force and duration and the sedimentation path-lengths. The proper centrifugation conditions can be selected using relatively simple theoretical estimates of the “cut-off” sizes of vesicles. Experimental verification on exosomes isolated from HT29 cell culture supernatant confirmed the main theoretical statements. Measured by the nanoparticle tracking analysis (NTA) technique, the concentration and size distribution of the vesicles after centrifugation agree with those theoretically expected. To simplify this “cut-off”-size-based adjustment of centrifugation protocol for any rotor, we developed a web-calculator.
Game-Based Rehabilitation for Myoelectric Prosthesis Control
Vujaklija, Ivan; Kayali, Fares; Purgathofer, Peter; Aszmann, Oskar C
2017-01-01
Background A high number of upper extremity myoelectric prosthesis users abandon their devices due to difficulties in prosthesis control and lack of motivation to train in absence of a physiotherapist. Virtual training systems, in the form of video games, provide patients with an entertaining and intuitive method for improved muscle coordination and improved overall control. Complementary to established rehabilitation protocols, it is highly beneficial for this virtual training process to start even before receiving the final prosthesis, and to be continued at home for as long as needed. Objective The aim of this study is to evaluate (1) the short-term effects of a commercially available electromyographic (EMG) system on controllability after a simple video game-based rehabilitation protocol, and (2) different input methods, control mechanisms, and games. Methods Eleven able-bodied participants with no prior experience in EMG control took part in this study. Participants were asked to perform a surface EMG test evaluating their provisional maximum muscle contraction, fine accuracy and isolation of electrode activation, and endurance control over at least 300 seconds. These assessments were carried out (1) in a Pregaming session before interacting with three EMG-controlled computer games, (2) in a Postgaming session after playing the games, and (3) in a Follow-Up session two days after the gaming protocol to evaluate short-term retention rate. After each game, participants were given a user evaluation survey for the assessment of the games and their input mechanisms. Participants also received a questionnaire regarding their intrinsic motivation (Intrinsic Motivation Inventory) at the end of the last game. Results Results showed a significant improvement in fine accuracy electrode activation (P<.01), electrode separation (P=.02), and endurance control (P<.01) from Pregaming EMG assessments to the Follow-Up measurement. The deviation around the EMG goal value diminished and the opposing electrode was activated less frequently. Participants had the most fun playing the games when collecting items and facing challenging game play. Conclusions Most upper limb amputees use a 2-channel myoelectric prosthesis control. This study demonstrates that this control can be effectively trained by employing a video game-based rehabilitation protocol. PMID:28183689
Isolation and Culture of Neural Crest Cells from Embryonic Murine Neural Tube
Pfaltzgraff, Elise R.; Mundell, Nathan A.; Labosky, Patricia A.
2012-01-01
The embryonic neural crest (NC) is a multipotent progenitor population that originates at the dorsal aspect of the neural tube, undergoes an epithelial to mesenchymal transition (EMT) and migrates throughout the embryo, giving rise to diverse cell types 1-3. NC also has the unique ability to influence the differentiation and maturation of target organs4-6. When explanted in vitro, NC progenitors undergo self-renewal, migrate and differentiate into a variety of tissue types including neurons, glia, smooth muscle cells, cartilage and bone. NC multipotency was first described from explants of the avian neural tube7-9. In vitro isolation of NC cells facilitates the study of NC dynamics including proliferation, migration, and multipotency. Further work in the avian and rat systems demonstrated that explanted NC cells retain their NC potential when transplanted back into the embryo10-13. Because these inherent cellular properties are preserved in explanted NC progenitors, the neural tube explant assay provides an attractive option for studying the NC in vitro. To attain a better understanding of the mammalian NC, many methods have been employed to isolate NC populations. NC-derived progenitors can be cultured from post-migratory locations in both the embryo and adult to study the dynamics of post-migratory NC progenitors11,14-20, however isolation of NC progenitors as they emigrate from the neural tube provides optimal preservation of NC cell potential and migratory properties13,21,22. Some protocols employ fluorescence activated cell sorting (FACS) to isolate a NC population enriched for particular progenitors11,13,14,17. However, when starting with early stage embryos, cell numbers adequate for analyses are difficult to obtain with FACS, complicating the isolation of early NC populations from individual embryos. Here, we describe an approach that does not rely on FACS and results in an approximately 96% pure NC population based on a Wnt1-Cre activated lineage reporter23. The method presented here is adapted from protocols optimized for the culture of rat NC11,13. The advantages of this protocol compared to previous methods are that 1) the cells are not grown on a feeder layer, 2) FACS is not required to obtain a relatively pure NC population, 3) premigratory NC cells are isolated and 4) results are easily quantified. Furthermore, this protocol can be used for isolation of NC from any mutant mouse model, facilitating the study of NC characteristics with different genetic manipulations. The limitation of this approach is that the NC is removed from the context of the embryo, which is known to influence the survival, migration and differentiation of the NC2,24-28. PMID:22688801
Machen, Alexandra; Kobayashi, Miwako; Connelly, Mary Robin
2013-01-01
Two novel protocols for inactivation and extraction were developed and used to identify 107 Mycobacterium clinical isolates, including Mycobacterium tuberculosis complex, from solid cultures using Vitek matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) mass spectrometry. The protocol using heat inactivation with sonication and cell disruption with glass beads resulted in 82.2% and 88.8% species and genus level identifications, respectively. PMID:24068013
Kurth, Andreas; Achenbach, John; Miller, Liljia; Mackay, Ian M; Pauli, Georg; Nitsche, Andreas
2008-01-01
After terrorists attacked the United States in 2001, the appearance of letters and other objects containing powdery substances with unknown potentials for biological threat focused attention on the speed, sensitivity, and reliability of diagnostic methods. This study summarizes the abilities and limitations of real-time PCR, electron microscopy (EM), and virus isolation when used to detect potential bioweapons. In particular, we investigated the inhibitory influences of different common household products present in environmental specimens on PCR yield, EM detection, and virus isolation. We used vaccinia virus as a model for orthopoxviruses by spiking it into specimens. In the second part of the study, we describe modifications of diagnostic methods to overcome inhibitory effects. A variety of PCR amplification enhancers, DNA extraction protocols, and applications of internal controls were evaluated to improve diagnostic simplicity, speed, and reliability. As a result, we strongly recommend using at least two different frontline techniques in parallel, e.g., EM and PCR. A positive result obtained by any one of these techniques should be followed by a biological method to confirm the putative diagnosis. Confirmatory methods include virus isolation followed by an agent-specific immunofluorescence assay to confirm the presence of replication-competent particles.
Pietzka, Ariane T.; Stöger, Anna; Huhulescu, Steliana; Allerberger, Franz; Ruppitsch, Werner
2011-01-01
The ability to accurately track Listeria monocytogenes strains involved in outbreaks is essential for control and prevention of listeriosis. Because current typing techniques are time-consuming, cost-intensive, technically demanding, and difficult to standardize, we developed a rapid and cost-effective method for typing of L. monocytogenes. In all, 172 clinical L. monocytogenes isolates and 20 isolates from culture collections were typed by high-resolution melting (HRM) curve analysis of a specific locus of the internalin B gene (inlB). All obtained HRM curve profiles were verified by sequence analysis. The 192 tested L. monocytogenes isolates yielded 15 specific HRM curve profiles. Sequence analysis revealed that these 15 HRM curve profiles correspond to 18 distinct inlB sequence types. The HRM curve profiles obtained correlated with the five phylogenetic groups I.1, I.2, II.1, II.2, and III. Thus, HRM curve analysis constitutes an inexpensive assay and represents an improvement in typing relative to classical serotyping or multiplex PCR typing protocols. This method provides a rapid and powerful screening tool for simultaneous preliminary typing of up to 384 samples in approximately 2 hours. PMID:21227395
Kurth, Andreas; Achenbach, John; Miller, Liljia; Mackay, Ian M.; Pauli, Georg; Nitsche, Andreas
2008-01-01
After terrorists attacked the United States in 2001, the appearance of letters and other objects containing powdery substances with unknown potentials for biological threat focused attention on the speed, sensitivity, and reliability of diagnostic methods. This study summarizes the abilities and limitations of real-time PCR, electron microscopy (EM), and virus isolation when used to detect potential bioweapons. In particular, we investigated the inhibitory influences of different common household products present in environmental specimens on PCR yield, EM detection, and virus isolation. We used vaccinia virus as a model for orthopoxviruses by spiking it into specimens. In the second part of the study, we describe modifications of diagnostic methods to overcome inhibitory effects. A variety of PCR amplification enhancers, DNA extraction protocols, and applications of internal controls were evaluated to improve diagnostic simplicity, speed, and reliability. As a result, we strongly recommend using at least two different frontline techniques in parallel, e.g., EM and PCR. A positive result obtained by any one of these techniques should be followed by a biological method to confirm the putative diagnosis. Confirmatory methods include virus isolation followed by an agent-specific immunofluorescence assay to confirm the presence of replication-competent particles. PMID:17965204
Two micro-scale protocols for the isolation of DNA from polysaccharide-rich plant tissue.
Shepherd, Lara D; McLay, Todd G B
2011-03-01
The high polysaccharide content of some plant species hinders the successful isolation of their DNA. As an alternative to the macro-extraction methods previously published for polysaccharide-rich plants, we present two techniques (STE/CTAB and HEPES/CTAB), which are performed in microcentrifuge tubes. These protocols are suitable for small amounts of silica gel-preserved plant tissue such as are commonly available from endangered plants. The critical step to remove polysaccharides was performing initial washes in either STE (0.25 M sucrose, 0.03 M Tris, 0.05 M EDTA) or HEPES (2% β-mercaptoethanol, 0.2% PVP, 0.1 M HEPES, pH 8.0) buffer. Precipitating the DNA at room temperature with isopropanol also aided in decreasing polysaccharide co-precipitation. Of the two protocols we present the STE/CTAB method has the advantages of being more cost-effective and avoiding the use of the hazardous chemical β-mercaptoethanol.
New Application of the Comet Assay
Cortés-Gutiérrez, Elva I.; Dávila-Rodríguez, Martha I.; Fernández, José Luís; López-Fernández, Carmen; Gosálbez, Altea; Gosálvez, Jaime
2011-01-01
The comet assay is a well-established, simple, versatile, visual, rapid, and sensitive tool used extensively to assess DNA damage and DNA repair quantitatively and qualitatively in single cells. The comet assay is most frequently used to analyze white blood cells or lymphocytes in human biomonitoring studies, although other cell types have been examined, including buccal, nasal, epithelial, and placental cells and even spermatozoa. This study was conducted to design a protocol that can be used to generate comets in subnuclear units, such as chromosomes. The new technique is based on the chromosome isolation protocols currently used for whole chromosome mounting in electron microscopy, coupled to the alkaline variant of the comet assay, to detect DNA damage. The results show that migrant DNA fragments can be visualized in whole nuclei and isolated chromosomes and that they exhibit patterns of DNA migration that depend on the level of DNA damage produced. This protocol has great potential for the highly reproducible study of DNA damage and repair in specific chromosomal domains. PMID:21540337
NASA Astrophysics Data System (ADS)
Amerimehr, Ali; Hadain Dehkordi, Massoud
2018-03-01
We analyze the security of a quantum secure direct communication and authentication protocol based on single photons. We first give an impersonation attack on the protocol. The cryptanalysis shows that there is a gap in the authentication procedure of the protocol so that an opponent can reveal the secret information by an undetectable attempt. We then propose an improvement for the protocol and show it closes the gap by applying a mutual authentication procedure. In the improved protocol single photons are transmitted once in a session, so it is easy to implement as the primary protocol. Furthermore, we use a novel technique for secret order rearrangement of photons by which not only quantum storage is eliminated also a secret key can be reused securely. So the new protocol is applicable in practical approaches like embedded system devices.
The Activity of Antimicrobial Surfaces Varies by Testing Protocol Utilized
Campos, Matias D.; Zucchi, Paola C.; Phung, Ann; Leonard, Steven N.; Hirsch, Elizabeth B.
2016-01-01
Background Contaminated hospital surfaces are an important source of nosocomial infections. A major obstacle in marketing antimicrobial surfaces is a lack of efficacy data based on standardized testing protocols. Aim We compared the efficacy of multiple testing protocols against several “antimicrobial” film surfaces. Methods Four clinical isolates were used: one Escherichia coli, one Klebsiella pneumoniae, and two Staphylococcus aureus strains. Two industry methods (modified ISO 22196 and ASTM E2149), a “dried droplet”, and a “transfer” method were tested against two commercially available antimicrobial films, one film in development, an untreated control, and a positive (silver) control film. At 2 (only ISO) and 24 hours following inoculation, bacteria were collected from film surfaces and enumerated. Results Compared to untreated films in all protocols, there were no significant differences in recovery on either commercial brand at 2 or 24 hours after inoculation. The silver surface demonstrated significant microbicidal activity (mean loss 4.9 Log10 CFU/ml) in all methods and time points with the exception of 2 hours in the ISO protocol and the transfer method. Using our novel droplet method, no differences between placebo and active surfaces were detected. The surface in development demonstrated variable activity depending on method, organism, and time point. The ISO demonstrated minimal activity at 2 hours but significant activity at 24 hours (mean 4.5 Log10 CFU/ml difference versus placebo). The ASTEM protocol exhibited significant differences in recovery of staphylococci (mean 5 Log10 CFU/ml) but not Gram-negative isolates (10 fold decrease). Minimal activity was observed with this film in the transfer method. Conclusions Varying results between protocols suggested that efficacy of antimicrobial surfaces cannot be easily and reproducibly compared. Clinical use should be considered and further development of representative methods is needed. PMID:27494336
Pasteran, Fernando; Gonzalez, Lisandro J.; Albornoz, Ezequiel; Bahr, Guillermo; Vila, Alejandro J.
2015-01-01
Accurate detection of carbapenemase-producing Gram-negative bacilli is of utmost importance for the control of nosocomial spread and the initiation of appropriate antimicrobial therapy. The modified Hodge test (MHT), a carbapenem inactivation assay, has shown poor sensitivity in detecting the worldwide spread of New Delhi metallo-β-lactamase (NDM). Recent studies demonstrated that NDM is a lipoprotein anchored to the outer membrane in Gram-negative bacteria, unlike all other known carbapenemases. Here we report that membrane anchoring of β-lactamases precludes detection of carbapenemase activity by the MHT. We also show that this limitation can be overcome by the addition of Triton X-100 during the test, which allows detection of NDM. We propose an improved version of the assay, called the Triton Hodge test (THT), which allows detection of membrane-bound carbapenemases with the addition of this nonionic surfactant. This test was challenged with a panel of 185 clinical isolates (145 carrying known carbapenemase-encoding genes and 40 carbapenemase nonproducers). The THT displayed test sensitivity of >90% against NDM-producing clinical isolates, while improving performance against other carbapenemases. Ertapenem provided the highest sensitivity (97 to 100%, depending on the type of carbapenemase), followed by meropenem (92.5 to 100%). Test specificity was not affected by the addition of Triton (87.5% and 92.5% with ertapenem and meropenem, respectively). This simple inexpensive test confers a large improvement to the sensitivity of the MHT for the detection of NDM and other carbapenemases. PMID:26719442
Ex vivo isolation protocols differentially affect the phenotype of human CD4+ T cells.
Bernard, Frédéric; Jaleco, Sara; Dardalhon, Valérie; Steinberg, Marcos; Yssel, Hans; Noraz, Nelly; Taylor, Naomi; Kinet, Sandrina
2002-12-20
Leukemic T cell lines have facilitated signal transduction studies but their physiological relevance is restricted. The use of primary T lymphocytes overcomes this limitation but it has long been speculated that methodological aspects of blood collection and the isolation procedure modify the phenotype of the cell. Here we demonstrate that several characteristics of human peripheral T cells are affected by the selection conditions. A significantly higher induction of the chemokine receptor CXCR4 was observed on CD4+ lymphocytes isolated by sheep red blood cell (SRBC) rosetting and CD4 MicroBeads as compared with positively selected CD4+ cells where the antibody/bead complex was immediately detached. These latter cells expressed CXCR4 at levels equivalent to that observed on CD4+ lymphocytes obtained by negative antibody-mediated selection. Furthermore, CD4+ cells isolated by SRBC rosetting and CD4 MicroBeads formed aggregates upon in vitro culture. CD4+ lymphocytes obtained by SRBC rosetting as well as those isolated following positive selection demonstrated basal phosphorylation of the extracellular signal-regulated kinase (ERK)-2. Altogether these data suggest that certain discrepancies concerning signal transduction in primary human T cells can be attributed to the selection conditions. Thus, it is essential to establish the parameters influenced by the isolation protocol in order to fully interpret T cell responses to antigens, chemokines, and cytokines.
Huang, Bixing; Heron, Brett A.; Gray, Bruce R.; Eglezos, Sofroni; Bates, John R.; Savill, John
2004-01-01
In epidemiological investigations of community legionellosis outbreaks, knowledge of the prevalence, distribution, and clinical significance (virulence) of environmental Legionella isolates is crucial for interpretation of the molecular subtyping results. To obtain such information for Legionella pneumophila serogroup 1 isolates, we used the standardized amplified fragment length polymorphism (AFLP) protocol of the European Working Group on Legionella Infection to subtype L. pneumophila SG1 isolates obtained from patients and water sources in Queensland, Australia. An AFLP genotype, termed AF1, was predominant in isolates from both patients (40.5%) and water (49.0%). The second most common AFLP genotype found in water isolates was AF16 (36.5%), but this genotype was not identified in the patient isolates. When virulence gene-based PCR assays for lvh and rtxA genes were applied to the isolates from patients and water, nearly all (65 of 66) AF1 strains had both virulence genes, lvh and rtxA. In contrast, neither the lvh nor the rtxA gene was found in the AF16 strains, except for one isolate with the rtxA gene. It appears that this may explain the failure to find this genotype in the isolates from patients even though it may be common in the environment. In view of the evidence that the AF1 genotype is the most common genotype among strains found in patients and water sources in this region, any suggested epidemiological link derived from comparing the AF1 genotype from patient isolates with the AF1 genotype from environmental isolates must be interpreted and acted on with caution. The use of virulence gene-based PCR assays applied to environmental samples may be helpful in determining the infection potential of the isolates involved. PMID:15365006
Bessat, Mohamed; Fadel, Amr
2018-06-19
Amyloodinium ocellatum, the causative agent of amyloodiniosis (marine velvet, velvet disease), affects marine and brackish fish in various warm and temperate habitats. We recorded disease outbreaks with high morbidity and mortality rates in marine-cultured European seabass Dicentrarchus labrax fry at 2 locations in northwest Egypt. The sudden outbreak, high morbidity and mortality rates, and skin lesions with a velvety appearance in affected fish all indicated A. ocellatum infection. This was further confirmed by microscopic findings of the parasitic stage (trophonts) in skin and gill smears. While ecological factors including water temperature and salinity were all amenable to parasite establishment and propagation, mortality rates differed between the 2 farms, with rates of mortality well correlated with prevalence and intensity of A. ocellatum infections. Characterization by PCR targeting rDNA gene fragments and subsequent DNA sequencing and phylogenetic analysis further confirmed the molecular identity of the A. ocellatum isolate, which was genetically similar to isolates from other geographical locations. Finally, an improved treatment method using dual hyposalination and copper sulfate exposure to increase the efficiency and decrease the toxicity of copper sulfate was tested. The gradual reduction in water salinity coupled with copper sulfate treatment was more efficient at controlling the disease than only applying copper sulfate. To our knowledge, this is the first parasitological and molecular characterization of A. ocellatum in marine cultures in Egypt. The high molecular identity and close phylogenetic relationship further confirmed the monophyletic nature of A. ocellatum isolates.
A rapid single-tube protocol for HAV detection by nested real-time PCR.
Hu, Yuan; Arsov, Ivica
2014-09-01
Infections by food-borne viruses such as hepatitis A virus (HAV) and norovirus are significant public health concerns worldwide. Since food-borne viruses are rarely confirmed through direct isolation from contaminated samples, highly sensitive molecular techniques remain the methods of choice for the detection of viral genetic material. Our group has previously developed a specific nested real-time PCR (NRT-PCR) assay for HAV detection that improved overall sensitivity. Furthermore in this study, we have developed a single-tube NRT-PCR approach for HAV detection in food samples that reduces the likelihood of cross contamination between tubes during sample manipulation. HAV RNA was isolated from HAV-spiked food samples and HAV-infected cell cultures. All reactions following HAV RNA isolation, including conventional reverse transcriptase PCR, nested-PCR, and RT-PCR were performed in a single tube. Our results demonstrated that all the samples tested positive by RT-PCR and nested-PCR were also positive by a single-tube NRT-PCR. The detection limits observed for HAV-infected cell cultures and HAV-spiked green onions were 0.1 and 1 PFU, respectively. This novel method retained the specificity and robustness of the original NRT-PCR method, while greatly reducing sample manipulation, turnaround time, and the risk of carry-over contamination. Single-tube NRT-PCR thus represents a promising new tool that can potentially facilitate the detection of HAV in foods thereby improving food safety and public health.
Biesemann, Christoph; Grønborg, Mads; Luquet, Elisa; Wichert, Sven P; Bernard, Véronique; Bungers, Simon R; Cooper, Ben; Varoqueaux, Frédérique; Li, Liyi; Byrne, Jennifer A; Urlaub, Henning; Jahn, Olaf; Brose, Nils; Herzog, Etienne
2014-01-01
For decades, neuroscientists have used enriched preparations of synaptic particles called synaptosomes to study synapse function. However, the interpretation of corresponding data is problematic as synaptosome preparations contain multiple types of synapses and non-synaptic neuronal and glial contaminants. We established a novel Fluorescence Activated Synaptosome Sorting (FASS) method that substantially improves conventional synaptosome enrichment protocols and enables high-resolution biochemical analyses of specific synapse subpopulations. Employing knock-in mice with fluorescent glutamatergic synapses, we show that FASS isolates intact ultrapure synaptosomes composed of a resealed presynaptic terminal and a postsynaptic density as assessed by light and electron microscopy. FASS synaptosomes contain bona fide glutamatergic synapse proteins but are almost devoid of other synapse types and extrasynaptic or glial contaminants. We identified 163 enriched proteins in FASS samples, of which FXYD6 and Tpd52 were validated as new synaptic proteins. FASS purification thus enables high-resolution biochemical analyses of specific synapse subpopulations in health and disease. PMID:24413018
Peters, Derek T.; Henderson, Christopher A.; Warren, Curtis R.; Friesen, Max; Xia, Fang; Becker, Caroline E.; Musunuru, Kiran; Cowan, Chad A.
2016-01-01
ABSTRACT Hepatocyte-like cells (HLCs) are derived from human pluripotent stem cells (hPSCs) in vitro, but differentiation protocols commonly give rise to a heterogeneous mixture of cells. This variability confounds the evaluation of in vitro functional assays performed using HLCs. Increased differentiation efficiency and more accurate approximation of the in vivo hepatocyte gene expression profile would improve the utility of hPSCs. Towards this goal, we demonstrate the purification of a subpopulation of functional HLCs using the hepatocyte surface marker asialoglycoprotein receptor 1 (ASGR1). We analyzed the expression profile of ASGR1-positive cells by microarray, and tested their ability to perform mature hepatocyte functions (albumin and urea secretion, cytochrome activity). By these measures, ASGR1-positive HLCs are enriched for the gene expression profile and functional characteristics of primary hepatocytes compared with unsorted HLCs. We have demonstrated that ASGR1-positive sorting isolates a functional subpopulation of HLCs from among the heterogeneous cellular population produced by directed differentiation. PMID:27143754
Nishizuka, Midori; Suzuki, Hiroki; Ara, Tomoka; Watanabe, Mari; Morita, Mami; Sato, Chisa; Tsuchida, Fumihiro; Seto, Junji; Amemura-Maekawa, Junko; Kura, Fumiaki; Takeda, Hiroaki
2014-06-01
The patient was an 83-year-old man hospitalized for Haemophilus influenzae pneumonia, who developed recurrent pneumonia after improvement of the initial episode. Legionella pneumophila serogroup 12 was isolated from the sputum, accompanied by increased serum antibody titers to L. pneumophila serogroup 12. Therefore, the patient was diagnosed as having Legionella pneumonia caused by L. pneumophila serogroup 12. Case reports of pneumonia caused by L. pneumophila serogroup 12 are rare, and the case described herein is the first report of clinical isolation of this organism in Japan. When the genotype was determined by the protocol of The European Working Group for Legionella Infections (Sequence-Based Typing [SBT] for epidemiological typing of L. pneumophila, Version 3.1), the sequence type was ST68. Imipenem/cilastatin therapy was found to be effective for the treatment of Legionella pneumonia in this patient. Copyright © 2014 Japanese Society of Chemotherapy and The Japanese Association for Infection Disease. Published by Elsevier Ltd. All rights reserved.
Oxidative aliphatic C-H fluorination with manganese catalysts and fluoride ion
Liu, Wei; Huang, Xiongyi; Groves, John T
2014-01-01
Fluorination is a reaction that is useful in improving the chemical stability and changing the binding affinity of biologically active compounds. The protocol described here can be used to replace aliphatic, C(sp3)-H hydrogen in small molecules with fluorine. Notably, isolated methylene groups and unactivated benzylic sites are accessible. The method uses readily available manganese porphyrin and manganese salen catalysts and various fluoride ion reagents, including silver fluoride (AgF), tetrabutylammonium fluoride and triethylamine trihydrofluoride (TREAT·HF), as the source of fluorine. Typically, the reactions afford 50–70% yield of mono-fluorinated products in one step. Two representative examples, the fragrance component celestolide and the nonsteroidal anti-inflammatory drug ibuprofen, are described; they produced useful isolated quantities (250–300 mg, ~50% yield) of fluorinated material over periods of 1–8 h. The procedures are performed in a typical fume hood using ordinary laboratory glassware. No special precautions to rigorously exclude water are required. PMID:24177292
Ginevan, Michael E
2002-12-01
This paper reviews the United States National Antimicrobial Resistance Monitoring System (NARMS). The data from this system have been used as the core basis of a recent proposal to stop the use of fluoroquinolones in poultry production, in an effort to reduce or remove a perceived threat to human health due to alleged increasing fluoroquinolone resistance among human Campylobacter isolates. An increase in resistance has the potential to render fluoroquinolone therapy of human gastrointestinal infections less effective. This review finds no evidence in the NARMS data to suggest that a rise in resistant Campylobacter isolates has occurred since fluoroquinolones were introduced for use in poultry. In addition, this review identifies a number of shortcomings in the NARMS program. These include lack of an overall sampling design, biases in the collection of isolates from animal samples, noncompliance of state departments of public health with NARMS protocols, lack of such basic data as genotype information on the organisms isolated, and, for animal samples, lack of measurements of bacterial load. Taken together, these problems indicate that the present NARMS data very likely overestimate resistance levels, and, at best, do not provide reliable information to quantify the extent and temporal trends of antimicrobial resistance in Campylobacter and other enteric organisms from human and animal populations. Ways to improve the quantitative rigor of the NARMS program and identify other data such as 'meta' data for human and animal samples, and data on the magnitude of other potential reservoirs of infection, including healthy humans, are suggested. Implementing these proposals would greatly enhance the value of the NARMS program as a tool for quantitative decision-making and aid in improving the quality of our food supply and human health care.
Martineau, Christine; Li, Xuejing; Lalancette, Cindy; Perreault, Thérèse; Fournier, Eric; Tremblay, Julien; Gonzales, Milagros; Yergeau, Étienne; Quach, Caroline
2018-06-13
Serratia marcescens is an environmental bacterium commonly associated with outbreaks in neonatal intensive care units (NICU). Investigation of S. marcescens outbreaks requires efficient recovery and typing of clinical and environmental isolates. In this study, we described how the use of next-generation sequencing applications, such as bacterial whole-genome sequencing (WGS) and bacterial community profiling, could improve S. marcescens outbreak investigation. Phylogenomic links and potential antibiotic resistance genes and plasmids in S. marcescens isolates were investigated using WGS, while bacterial communities and relative abundances of Serratia in environmental samples were assessed using sequencing of bacterial phylogenetic marker genes (16S rRNA and gyrB genes). Typing results obtained using WGS for the ten S. marcescens isolates recovered during a NICU outbreak investigation were highly consistent with those from pulse-field gel electrophoresis (PFGE), the current gold standard typing method for this bacterium. WGS also allowed for the identification of genes associated with antibiotic resistance in all isolates, while no plasmid was detected. Sequencing of the 16S rRNA and gyrB genes both showed higher relative abundances of Serratia in environmental sampling sites that were in close contact with infected babies. Much lower relative abundances of Serratia were observed following disinfection of a room, indicating that the protocol used was efficient. Variations in the bacterial community composition and structure following room disinfection and between sampling sites were also identified through 16S rRNA gene sequencing. Globally, results from this study highlight the potential for next-generation sequencing tools to improve and facilitate outbreak investigation. Copyright © 2018 American Society for Microbiology.
Editing wild points in isolation - Fast agreement for reliable systems (Preliminary version)
NASA Technical Reports Server (NTRS)
Kearns, Phil; Evans, Carol
1989-01-01
Consideration is given to the intuitively appealing notion of discarding sensor values which are strongly suspected of being erroneous in a modified approximate agreement protocol. Approximate agreement with editing imposes a time bound upon the convergence of the protocol - no such bound was possible for the original approximate agreement protocol. This new approach is potentially useful in the construction of asynchronous fault tolerant systems. The main result is that a wild-point replacement technique called t-worst editing can be shown to guarantee convergence of the approximate agreement protocol to a valid agreement value. Results are presented for a four-processor synchronous system in which a single processor may be faulty.
Scheid, Lisa-Mareike; Weber, Cornelia; Bopp, Nasrin; Mosqueira, Matias; Fink, Rainer H. A.
2017-01-01
The in vitro motility assay (IVMA) is a technique that enables the measurement of the interaction between actin and myosin providing a relatively simple model to understand the mechanical muscle function. For actin-myosin IVMA, myosin is immobilized in a measurement chamber, where it converts chemical energy provided by ATP hydrolysis into mechanical energy. The result is the movement of fluorescently labeled actin filaments that can be recorded microscopically and analyzed quantitatively. Resulting sliding speeds and patterns help to characterize the underlying actin-myosin interaction that can be affected by different factors such as mutations or active compounds. Additionally, modulatory actions of the regulatory proteins tropomyosin and troponin in the presence of calcium on actin-myosin interaction can be studied with the IVMA. Zebrafish is considered a suitable model organism for cardiovascular and skeletal muscle research. In this context, straightforward protocols for the isolation and use of zebrafish muscle proteins in the IVMA would provide a useful tool in molecular studies. Currently, there are no protocols available for the mentioned purpose. Therefore, we developed fast and easy protocols for characterization of zebrafish proteins in the IVMA. Our protocols enable the interested researcher to (i) isolate actin from zebrafish skeletal muscle and (ii) extract functionally intact myosin from cardiac and skeletal muscle of individual adult zebrafish. Zebrafish tail muscle actin is isolated after acetone powder preparation, polymerized, and labeled with Rhodamine-Phalloidin. Myosin from ventricles of adult zebrafish is extracted directly into IVMA flow-cells. The same extraction protocol is applicable for comparably small tissue pieces as from zebrafish tail, mouse and frog muscle. After addition of the fluorescently labeled F-actin from zebrafish—or other origin—and ATP, sliding movement can be visualized using a fluorescence microscope and an intensified CCD camera. Taken together, we introduce a method for functional analysis in zebrafish cardiac and skeletal muscle research to study mutations at the molecular level of thick or thin filament proteins. Additionally, preliminary data indicate the usefulness of the presented method to perform the IVMA with myosin extracted from muscles of other animal models. PMID:28620318
Cuenca-Fernández, Francisco; Ruiz-Teba, Ana; López-Contreras, Gracia; Arellano, Raúl
2018-06-14
Cuenca-Fernández, F, Ruiz-Teba, A, López-Contreras, G, and Arellano, R. Effects of 2 types of activation protocols based on postactivation potentiation on 50-m freestyle performance. J Strength Cond Res XX(X): 000-000, 2018-Postactivation potentiation (PAP) is a phenomenon which improves muscle contractility, strength, and speed in sporting performances through previously applied maximal or submaximal loads on the muscle system. This study aimed to assess the effects of 2 types of activation protocols based on PAP, on sprint swimming performance. A repeated-measures design was used to compare 3 different scenarios before a 50-m race. First, all of the participants performed a standard warm-up (SWU), consisting of a 400-m swim followed by dynamic stretching. This protocol acted as the control. Subsequently, the swimmers were randomly assigned into 2 groups: the swimmers in the first group performed the SWU followed by a PAP one-repetition maximum warm-up (RMWU), consisting of 3 "lunge" and 3 "arm stroke" repetitions, both at 85% of the one-repetition maximum. The swimmers in the second group performed the SWU followed by a PAP eccentric flywheel warm-up (EWU), consisting of one set of 4 repetitions of exercises of both the lower and upper limbs on an adapted eccentric flywheel at the maximal voluntary contraction. The time required for the swimmers to swim 5 and 10 m was shorter with the PAP protocols. The swimming velocity of the swimmers who underwent the EWU and RMWU protocols was faster at 5 and 10 m. The best total swimming time was not influenced by any of the protocols. When isolating swimming (excluding start performance and turn), best time was achieved with the SWU and RMWU compared with EWU (SWU: 20.86 ± 0.95 seconds; EWU: 21.25 ± 1.12 seconds; RMWU: 20.97 ± 1.22 seconds). In conclusion, a warm-up based on PAP protocols might exert an influence on performance in the first meters of a 50-m race. Nevertheless, other factors, such as fatigue, could modify swimming patterns and yield results contradictory to those of the desired task.
Wattal, C; Oberoi, J K; Goel, N; Raveendran, R; Khanna, S
2017-05-01
The study evaluates the utility of matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) Vitek MS for identification of microorganisms in the routine clinical microbiology laboratory. From May 2013 to April 2014, microbial isolates recovered from various clinical samples were identified by Vitek MS. In case of failure to identify by Vitek MS, the isolate was identified using the Vitek 2 system (bioMerieux, France) and serotyping wherever applicable or otherwise by nucleic acid-mediated methods. All the moulds were identified by Lactophenol blue mounts, and mycobacterial isolates were identified by molecular identification systems including AccuProbe (bioMerieux, France) or GenoType Mycobacterium CM (Hain Lifescience, Germany). Out of the 12,003 isolates, the Vitek MS gave a good overall ID at the genus and or species level up to 97.7% for bacterial isolates, 92.8% for yeasts and 80% for filamentous fungi. Of the 26 mycobacteria tested, only 42.3% could be identified using the Saramis RUO (Research Use Only) database. VITEK MS could not identify 34 of the 35 yeast isolates identified as C. haemulonii by Vitek 2. Subsequently, 17 of these isolates were identified as Candida auris (not present in the Vitek MS database) by 18S rRNA sequencing. Using these strains, an in-house superspectrum of C. auris was created in the VITEK MS database. Use of MALDI-TOF MS allows a rapid identification of aerobic bacteria and yeasts in clinical practice. However, improved sample extraction protocols and database upgrades with inclusion of locally representative strains is required, especially for moulds.
Microcomputer Nurse-Practitioner Protocols
Way, Anthony B.; Rowley, Blair A.; White, Melanie A.
1982-01-01
We have developed a set of protocols on a microcomputer to assist in the management of a geographically isolated nurse practitioner. If a mid-level practitioner is supervised by a physician, some system is needed to ensure that approved care is being provided. The currently available paper-based protocols do not adequately serve all the needs for training, auditing, and record keeping. Conversely, adequate systems based on large computers are not feasible for small clinics. We have therefore developed a microcomputer-based system of protocols for a small rural nurse-practitioner's clinic. Our programs are designed for direct use by the practitioners while the patient is in the clinic. The user is given immediate feedback about any errors. The supervisor is later provided with a summary of the protocol uses and errors, and a copy of any erroneous records. The system appears to be easy to use by the nurse practitioner. The protocols are quickly learned and auditing is facilitated.
Cryptanalysis and Improvements for the Quantum Private Comparison Protocol Using EPR Pairs
NASA Astrophysics Data System (ADS)
Wang, Cong; Xu, Gang; Yang, Yi-Xian
2013-07-01
In this paper, we carry out an in-depth analysis of the quantum private comparison (QPC) protocol with the semi-honest third party (TP). The security of QPC protocol using the EPR pairs is re-examined. Unfortunately, we find that TP can use the fake EPR pairs to steal all the secret information. Furthermore, we give two simple and feasible solutions to improve the original QPC protocol. It is shown that the improved protocol is secure, which can resist various kinds of attacks from both the outside eavesdroppers and the inside participants, even the semi-honest TP.
A Secure and Efficient Handover Authentication Protocol for Wireless Networks
Wang, Weijia; Hu, Lei
2014-01-01
Handover authentication protocol is a promising access control technology in the fields of WLANs and mobile wireless sensor networks. In this paper, we firstly review an efficient handover authentication protocol, named PairHand, and its existing security attacks and improvements. Then, we present an improved key recovery attack by using the linearly combining method and reanalyze its feasibility on the improved PairHand protocol. Finally, we present a new handover authentication protocol, which not only achieves the same desirable efficiency features of PairHand, but enjoys the provable security in the random oracle model. PMID:24971471
Hao, Q; Chen, X L; Ma, L; Ye, X; Wang, H; Wang, T T; Hu, Y; Zhao, Y L
2018-03-01
The cerebral arteriovenous malformation (cAVM) is a usual and continually unaware reason of heamorrhage and seizure. It contains of feeder arteries, drain veins and abnormal vessel nets. However, pathologic mechanisms of the development of cAVM are unknown. The purpose of this study was to explore a novel protocol to isolate, culture and passage endothelial cells (ECs) from human cAVM lesions. We developed a protocol for isolating and growing ECs from eight patients with cAVM. The tissues were microsurgically removed from cAVM lesion and were digested by 0.25% Trypsin-EDTA, and cultured in ECM medium. ECs were selected by FACS and confirmed their EC origin by immunocytochemistry of the basic expression patterns of CD31 and CD34. LDL-uptake and capillary tube formation were used to determine their functional features. The isolated cAVM-ECs exhibited contact inhibition of growth and appearance of rounded cobblestone. cAVM-ECs were CD31- and CD34-positive. In functional assays, cAVM-ECs were able to uptake LDL and form capillary tubes. cAVM-ECs from younger patients proliferated faster than that from elders, and cAVM-ECs were less stable than normal artery ECs. In addition, cAVM-ECs appeared to more easily transform into mesenchymal cells than normal artery ECs. Using the protocol, isolated cAVM-ECs are stably established, and retain their endothelial phenotypes. These cAVM-ECs may provide a biological tool to examine molecular phenotypes and mechanisms responsible for human cAVM. Copyright © 2017 Elsevier Inc. All rights reserved.
In vitro folding of inclusion body proteins.
Rudolph, R; Lilie, H
1996-01-01
Insoluble, inactive inclusion bodies are frequently formed upon recombinant protein production in transformed microorganisms. These inclusion bodies, which contain the recombinant protein in an highly enriched form, can be isolated by solid/liquid separation. After solubilization, native proteins can be generated from the inactive material by using in vitro folding techniques. New folding procedures have been developed for efficient in vitro reconstitution of complex hydrophobic, multidomain, oligomeric, or highly disulfide-bonded proteins. These protocols take into account process parameters such as protein concentration, catalysis of disulfide bond formation, temperature, pH, and ionic strength, as well as specific solvent ingredients that reduce unproductive side reactions. Modification of the protein sequence has been exploited to improve in vitro folding.
Thermogravimetric Analysis of Single-Wall Carbon Nanotubes
NASA Technical Reports Server (NTRS)
Arepalli, Sivram; Nikolaev, Pavel; Gorelik, Olga
2010-01-01
An improved protocol for thermogravimetric analysis (TGA) of samples of single-wall carbon nanotube (SWCNT) material has been developed to increase the degree of consistency among results so that meaningful comparisons can be made among different samples. This improved TGA protocol is suitable for incorporation into the protocol for characterization of carbon nanotube material. In most cases, TGA of carbon nanotube materials is performed in gas mixtures that contain oxygen at various concentrations. The improved protocol is summarized.
Ruiz, Francisco J; Luciano, Carmen
2009-08-01
Acceptance and Commitment Therapy (ACT) is shown to be effective in relatively distant fields from the so-called psychological disorders. One of these areas is sport performance improvement. The aim of the current study is to expand the application of brief ACT protocols to improve chess-players' performance. In a previous study, a brief protocol was applied to international-level adult chess-players that was effective. The current study aims to apply an equivalent brief ACT protocol, but in this case, applied in a group format to promising young chess-players. In addition, this brief protocol is compared to a non-intervention control condition. Results show that the ACT brief protocol improved the performance in 5 out of 7 participants, and that none of the chess-players in the control condition reached the established change criterion. The differences between the conditions in chess performance were statistically significant. The results are discussed, emphasizing the replicated impact of a brief ACT protocol on the improvement of chess-players' performance.
Houston, Megan N; Hodson, Victoria E; Adams, Kelda K E; Hoch, Johanna M
2015-02-01
Hamstring tightness is common among physically active individuals. In addition to limiting range of motion and increasing the risk of muscle strain, hamstring tightness contributes to a variety of orthopedic conditions. Therefore, clinicians continue to identify effective methods to increase flexibility. Although hamstring tightness is typically treated with common stretching techniques such as static stretching and proprioceptive neuromuscular facilitation, it has been suggested that whole-body-vibration (WBV) training may improve hamstring flexibility. Can WBV training, used in isolation or in combination with common stretching protocols or exercise, improve hamstring flexibility in physically active young adults? Summary of Key Findings: Of the included studies, 4 demonstrated statistically significant improvements in hamstring flexibility in the intervention group, and 1 study found minor improvements over time in the intervention group after treatment. Clinical Bottom Line: There is moderate evidence to support the use of WBV training to improve hamstring flexibility in physically active young adults. There is grade B evidence that WBV training improves hamstring flexibility in physically active adults. The Centre of Evidence Based Medicine recommends a grade of B for level 2 evidence with consistent findings.
Shake and stew: a non-destructive PCR-ready DNA isolation method from a single preserved fish larva.
Alvarado Bremer, J R; Smith, B L; Moulton, D L; Lu, C-P; Cornic, M
2014-01-01
A rapid non-destructive alternative to isolate DNA from an individual fish larva is presented, based on the suspension of epithelial cells through vortex forces, and the release of DNA in a heated alkaline solution. DNA from >6056 fish larvae isolated using this protocol has yielded a high PCR amplification success rate (>93%), suggesting its applicability to other taxonomic groups or sources when tissue amount is the limiting factor. © 2014 The Fisheries Society of the British Isles.
Iuso, Arcangela; Repp, Birgit; Biagosch, Caroline; Terrile, Caterina; Prokisch, Holger
2017-01-01
Working with isolated mitochondria is the gold standard approach to investigate the function of the electron transport chain in tissues, free from the influence of other cellular factors. In this chapter, we outline a detailed protocol to measure the rate of oxygen consumption (OCR) with the high-throughput analyzer Seahorse XF96. More importantly, this protocol wants to provide practical tips for handling many different samples at once, and take a real advantage of using a high-throughput system. As a proof of concept, we have isolated mitochondria from brain, heart, liver, muscle, kidney, and lung of a wild-type mouse, and measured basal respiration (State II), ADP-stimulated respiration (State III), non-ADP-stimulated respiration (State IV o ), and FCCP-stimulated respiration (State III u ) using respiratory substrates specific to the respiratory chain complex I (RCCI) and complex II (RCCII). Mitochondrial purification and Seahorse runs were performed in less than eight working hours.
La Scola, B; Fournier, P E; Brouqui, P; Raoult, D
2001-05-01
As part of a survey for trench fever among homeless people in Marseilles, France, we attempted isolation of Bartonella quintana from body lice. A decontamination protocol of immersion in 70% ethanol with 0.2% iodine was devised and was tested with a laboratory colony of body lice. Lice which had been experimentally contaminated with either Escherichia coli, Staphylococcus epidermidis, or Acinetobacter spp. were successfully decontaminated, and this process did not prevent the culture of B. quintana from these lice. One hundred sixty-one lice obtained from homeless patients were studied by the protocol. B. quintana was isolated on axenic medium from 15 of 161 body lice and was detected in 41 of 161 lice by PCR. Acinetobacter spp. and Serratia marcescens were also isolated from body lice. The sensitivities of PCR and culture of B. quintana were 98 and 36%, respectively. These procedures may be useful for epidemiologic studies of trench fever and for the recovery of strains for characterization and comparison.
Cyclotide isolation and characterization.
Craik, David J; Henriques, Sonia Troeira; Mylne, Joshua S; Wang, Conan K
2012-01-01
Cyclotides are disulfide-rich cyclic peptides produced by plants with the presumed natural function of defense agents against insect pests. They are present in a wide range of plant tissues, being ribosomally synthesized via precursor proteins that are posttranslationally processed to produce mature peptides with a characteristic cyclic backbone and cystine knot motif associated with their six conserved cysteine residues. Their processing is not fully understood but involves asparaginyl endoproteinase activity. In addition to interest in their defense roles and their unique topologies, cyclotides have attracted attention as potential templates in peptide-based drug design applications. This chapter provides protocols for the isolation of cyclotides from plants, their detection and sequencing by mass spectrometry, and their structural analysis by NMR, as well as describing methods for the isolation of nucleic acid sequences that encode their precursor proteins. Assays to assess their membrane-binding interactions are also described. These protocols provide a "starter kit" for researchers entering the cyclotide field. Copyright © 2012 Elsevier Inc. All rights reserved.
Isolation and characterization of porcine adipose tissue-derived adult stem cells.
Williams, Kellie J; Picou, Alicia A; Kish, Sharon L; Giraldo, Angelica M; Godke, Robert A; Bondioli, Kenneth R
2008-01-01
Stem cell characteristics such as self-renewal, differentiation and expression of CD34 and CD44 stem cell markers have not been identified in porcine adipose tissue-derived adult stem (ADAS) cells. The objective of this study was to develop a protocol for the isolation and culture of porcine adipose tissue-derived cells and to determine stem cell-like characteristics. Primary cultures were established and cell cultures were maintained. Cloning capacity was determined using a ring cloning procedure. Primary cultures and clones were differentiated and stained for multiple differentiated phenotypes. CD34 and CD44 messenger ribonucleic acid (mRNA) was isolated and reverse transcriptase polymerase chain reaction was used to compare expression profiles. An average of 2,700,000 nucleated cells/ml was isolated; 26% were adherent, and cells completed a cell cycle approximately every 3.3 days. Ring cloning identified 19 colonies. Primary cultures and clones were determined to differentiate along osteogenic, adipogenic and chondrogenic tissue lineages. The mRNA expression profiles showed CD34 expression was higher for undifferentiated ADAS cells versus differentiated cell types and the CD34 expression level was lower than that of CD44 among differentiated cells. Improved culture conditions and defined cellular characteristics of these porcine ADAS cells have been identified. Porcine ADAS can self-renew, can differentiate into multiple tissue lineages and they express CD34. Copyright 2008 S. Karger AG, Basel.
di Rienzo, Valentina; Bubici, Giovanni; Montemurro, Cinzia; Cillo, Fabrizio
2018-01-01
In tomato, resistance to Tomato spotted wilt virus (TSWV) is conferred by the dominant gene, designated Sw-5. Virulent Sw-5 resistance breaking (SRB) mutants of TSWV have been reported on Sw-5 tomato cultivars. Two different PCR-based allelic discrimination techniques, namely Custom TaqMan™ SNP Genotyping and high-resolution melting (HRM) assays, were developed and compared for their ability to distinguish between avirulent (Sw-5 non-infecting, SNI) and SRB biotypes. TaqMan assays proved to be more sensitive (threshold of detection in a range of 50-70 TSWV RNA copies) and more reliable than HRM, assigning 25 TSWV isolates to their correct genotype with an accuracy of 100%. Moreover, the TaqMan SNP assays were further improved developing a rapid and simple protocol that included crude leaf extraction for RNA template preparations. On the other hand, HRM assays showed higher levels of sensitivity than TaqMan when used to co-detect both biotypes in different artificial mixtures. These diagnostic assays contributed to gain preliminary information on the epidemiology of TSWV isolates in open field conditions. In fact, the presented data suggest that SRB isolates are present as stable populations established year round, persisting on both winter (globe artichoke) and summer (tomato) crops, in the same cultivated areas of Southern Italy.
Bhatia, V K; Sharma, P C
2015-01-01
Various antifungal agents both topical and systemic have been introduced into clinical practice for effectively treating dermatophytic conditions. Dermatophytosis is the infection of keratinised tissues caused by fungal species of genera Trichophyton, Epidermophyton and Microsporum, commonly known as dermatophytes affecting 20-25% of the world's population. The present study aims at determining the susceptibility patterns of dermatophyte species recovered from superficial mycoses of human patients in Himachal Pradesh to antifungal agents; itraconazole, terbinafine and ketoconazole. The study also aims at determining the minimum inhibitory concentrations (MICs) of these agents following the recommended protocol of Clinical and Laboratory Standards Institute (CLSI) (M38-A2). A total of 53 isolates of dermatophytes (T. mentagrophyte-34 in no., T. rubrum-18 and M. gypseum-1) recovered from the superficial mycoses were examined. Broth microdilution method M38-A2 approved protocol of CLSI (2008) for filamentous fungi was followed for determining the susceptibility of dermatophyte species. T. mentagrophyte isolates were found more susceptible to both itraconazole and ketoconazole as compared to terbinafine (MIC50: 0.125 µg/ml for itraconazole, 0.0625 µg/ml for ketoconazole and 0.5 µg/ml for terbinafine). Three isolates of T. mentagrophytes (VBS-5, VBSo-3 and VBSo-73) and one isolate of T. rubrum (VBPo-9) had higher MIC values of itraconazole (1 µg/ml). Similarly, the higher MIC values of ketoconazole were observed in case of only three isolates of T. mentagrophyte (VBSo-30 = 2 µg/ml; VBSo-44, VBM-2 = 1 µg/ml). The comparative analysis of the three antifungal drugs based on t-test revealed that 'itraconazole and terbinafine' and 'terbinafine and ketoconazole' were found independent based on the P < 0.005 in case of T. mentagrophyte isolates. In case of T. rubrum, the similarity existed between MIC values of 'itraconazole and ketoconazole' and 'terbinafine and ketoconazole'. The MIC values observed in the present study based on standard protocol M38-A2 of CLSI 2008 might serve as reference for further studies covering large number of isolates from different geographic regions of the state. Such studies might reflect on the acquisition of drug resistance among isolates of dermatophyte species based on MIC values.
An improved ATAC-seq protocol reduces background and enables interrogation of frozen tissues.
Corces, M Ryan; Trevino, Alexandro E; Hamilton, Emily G; Greenside, Peyton G; Sinnott-Armstrong, Nicholas A; Vesuna, Sam; Satpathy, Ansuman T; Rubin, Adam J; Montine, Kathleen S; Wu, Beijing; Kathiria, Arwa; Cho, Seung Woo; Mumbach, Maxwell R; Carter, Ava C; Kasowski, Maya; Orloff, Lisa A; Risca, Viviana I; Kundaje, Anshul; Khavari, Paul A; Montine, Thomas J; Greenleaf, William J; Chang, Howard Y
2017-10-01
We present Omni-ATAC, an improved ATAC-seq protocol for chromatin accessibility profiling that works across multiple applications with substantial improvement of signal-to-background ratio and information content. The Omni-ATAC protocol generates chromatin accessibility profiles from archival frozen tissue samples and 50-μm sections, revealing the activities of disease-associated DNA elements in distinct human brain structures. The Omni-ATAC protocol enables the interrogation of personal regulomes in tissue context and translational studies.
NASA Astrophysics Data System (ADS)
Sun, Ying; Wen, Qiao-yan; Zhu, Fu-chen
2010-01-01
The security of the multiparty quantum secret sharing protocol presented by Zhang [Z.J. Zhang, Physica A, 361 (2006) 233] is analyzed. It is shown that this protocol is vulnerable to the insider attack since eavesdropping detection is performed only when all states arrive at the last agent. We propose an attack strategy and give an improved version of the original protocol. The improved protocol is robust and has the same traits with the original one.
The nature and treatment of phonological text agraphia.
Beeson, Pélagie M; Rising, Kindle; DeMarco, Andrew T; Foley, Taylor Howard; Rapcsak, Steven Z
2018-06-01
Phonological alexia and agraphia are written language disorders characterised by disproportionate difficulty reading and spelling nonwords in comparison to real words. In phonological alexia, it has been shown that, despite relatively accurate reading of words in isolation, text-level reading deficits are often marked and persistent. Specifically, some individuals demonstrate difficulty reading functors and affixes in sentences, a profile referred to as phonological text alexia. In this paper, we demonstrate an analogous manifestation of the phonological impairment on text-level writing and suggest the term "phonological text agraphia". We examined four individuals with phonological alexia/agraphia who also showed disproportionate difficulty writing well-formed sentences in comparison to their grammatical competence in spoken utterances. Implementation of a phonological treatment protocol resulted in significantly improved sublexical phonology skills as well as improvements in grammatical accuracy of written narratives. These findings support the notion of a common phonological impairment underlying nonword reading/spelling deficits and sentence-level difficulties.
Dendrobium micropropagation: a review.
da Silva, Jaime A Teixeira; Cardoso, Jean Carlos; Dobránszki, Judit; Zeng, Songjun
2015-05-01
Dendrobium is one of the largest and most important (ornamentally and medicinally) orchid genera. Tissue culture is now an established method for the effective propagation of members of this genus. This review provides a detailed overview of the Dendrobium micropropagation literature. Through a chronological analysis, aspects such as explant, basal medium, plant growth regulators, culture conditions and final organogenic outcome are chronicled in detail. This review will allow Dendrobium specialists to use the information that has been documented to establish, more efficiently, protocols for their own germplasm and to improve in vitro culture conditions based on the optimized parameters detailed in this review. Not only will this expand the use for mass propagation, but will also allow for the conservation of important germplasm. Information on the in vitro responses of Dendrobium for developing efficient protocols for breeding techniques based on tissue culture, such as polyploidization, somatic hybridization, isolation of mutants and somaclonal variants and for synthetic seed and bioreactor technology, or for genetic transformation, is discussed in this review. This is the first such review on this genus and represents half a decade of literature dedicated to Dendrobium micropropagation.
Capturing Three-Dimensional Genome Organization in Individual Cells by Single-Cell Hi-C.
Nagano, Takashi; Wingett, Steven W; Fraser, Peter
2017-01-01
Hi-C is a powerful method to investigate genome-wide, higher-order chromatin and chromosome conformations averaged from a population of cells. To expand the potential of Hi-C for single-cell analysis, we developed single-cell Hi-C. Similar to the existing "ensemble" Hi-C method, single-cell Hi-C detects proximity-dependent ligation events between cross-linked and restriction-digested chromatin fragments in cells. A major difference between the single-cell Hi-C and ensemble Hi-C protocol is that the proximity-dependent ligation is carried out in the nucleus. This allows the isolation of individual cells in which nearly the entire Hi-C procedure has been carried out, enabling the production of a Hi-C library and data from individual cells. With this new method, we studied genome conformations and found evidence for conserved topological domain organization from cell to cell, but highly variable interdomain contacts and chromosome folding genome wide. In addition, we found that the single-cell Hi-C protocol provided cleaner results with less technical noise suggesting it could be used to improve the ensemble Hi-C technique.
A comparative study of routing protocols of heterogeneous wireless sensor networks.
Han, Guangjie; Jiang, Xu; Qian, Aihua; Rodrigues, Joel J P C; Cheng, Long
2014-01-01
Recently, heterogeneous wireless sensor network (HWSN) routing protocols have drawn more and more attention. Various HWSN routing protocols have been proposed to improve the performance of HWSNs. Among these protocols, hierarchical HWSN routing protocols can improve the performance of the network significantly. In this paper, we will evaluate three hierarchical HWSN protocols proposed recently--EDFCM, MCR, and EEPCA--together with two previous classical routing protocols--LEACH and SEP. We mainly focus on the round of the first node dies (also called the stable period) and the number of packets sent to sink, which is an important aspect to evaluate the monitoring ability of a protocol. We conduct a lot of experiments and simulations on Matlab to analyze the performance of the five routing protocols.
Ferrer, Gerald A; Miller, R Matthew; Zlotnicki, Jason P; Tashman, Scott; Irrgang, James J; Musahl, Volker; Debski, Richard E
2018-01-01
Rotator cuff tears are a significant clinical problem, with exercise therapy being a common treatment option for patients. Failure rates of exercise therapy may be due to the failure to improve glenohumeral kinematics. Tears involving the supraspinatus may result in altered glenohumeral kinematics and joint instability for internal/external rotation with the arm at the side because not all muscles used to stabilize the glenohumeral joint are functioning normally. The objective of the study is to assess in vivo glenohumeral kinematic changes for internal/external rotation motions with the arm at the side of patients with a symptomatic full-thickness supraspinatus tear before and after a 12-week exercise therapy programme. Five patients underwent dynamic stereoradiography analysis before and after a 12-week exercise therapy protocol to measure changes in glenohumeral kinematics during transverse plane internal/external rotation with the arm at the side. Patient-reported outcomes and shoulder strength were also evaluated. No patient sought surgery immediately following exercise therapy. Significant improvements in isometric shoulder strength and patient-reported outcomes were observed (p < 0.05). No significant changes in glenohumeral kinematics following physical therapy were found. Isolated supraspinatus tears resulted in increased joint translations compared to healthy controls from the previous literature for internal/external rotation with the arm at the side. Despite satisfactory clinical outcomes following exercise therapy, glenohumeral kinematics did not change. The lack of changes may be due to the motion studied or the focus of current exercise therapy protocols being increasing shoulder strength and restoring range of motion. Current exercise therapy protocols should be adapted to also focus on restoring glenohumeral kinematics to improve joint stability since exercise therapy may have different effects depending on the motions of daily living. Prognostic study, Level II.
Burcal, Christopher J; Trier, Alejandra Y; Wikstrom, Erik A
2017-09-01
Both balance training and selected interventions meant to target sensory structures (STARS) have been shown to be effective at restoring deficits associated with chronic ankle instability (CAI). Clinicians often use multiple treatment modalities in patients with CAI. However, evidence for combined intervention effectiveness in CAI patients remains limited. To determine if augmenting a balance-training protocol with STARS (BTS) results in greater improvements than balance training (BT) alone in those with CAI. Randomized-controlled trial. Research laboratory. 24 CAI participants (age 21.3 ± 2.0 y; height 169.8 ± 12.9 cm; mass 72.5 ± 22.2 kg) were randomized into 2 groups: BT and BTS. Participants completed a 4-week progression-based balance-training protocol consisting of 3 20-min sessions per week. The experimental group also received a 5-min set of STARS treatments consisting of calf stretching, plantar massage, ankle joint mobilizations, and ankle joint traction before each balance-training session. Outcomes included self-assessed disability, Star Excursion Balance Test reach distance, and time-to-boundary calculated from static balance trials. All outcomes were assessed before, and 24-hours and 1-week after protocol completion. Self-assessed disability was also captured 1-month after the intervention. No significant group differences were identified (P > .10). Both groups demonstrated improvements in all outcome categories after the interventions (P < .10), many of which were retained at 1-week posttest (P < .10). Although 90% CIs include zero, effect sizes favor BTS. Similarly, only the BTS group exceeded the minimal detectable change for time-to-boundary outcomes. While statistically no more effective, exceeding minimal detectable change scores and favorable effect sizes suggest that a 4-week progressive BTS program may be more effective at improving self-assessed disability and postural control in CAI patients than balance training in isolation.
Fatahinia, M; Halvaeezadeh, M; Rezaei-Matehkolaei, A
2017-06-01
Comparing the activities of secreted enzymes in different fungal species can improve our understanding of their pathogenic role. Secretion of various enzymes by Candida species has been considered for determination of their virulence in different Candida infections including vulvovaginitis. The aim of this study was to determine and compare the activity of secreted enzymes in Candidia strains isolated from women suspected to vulvovaginal candidiasis (VVC) and referred to some health centers in Khuzestan, Southwestern Iran. The vaginal secretion samples were taken by swap from 250 suspected women with symptoms of vulvovaginal candidiasis and cultured on CHROMagar Candida medium. Identification of the isolated Candida from culture positive samples performed by the color of colonies and some standard mycological procedures. Activities of phospholipase, hemolysin-α, hemolysin-β, esterase and proteinase were measured in vitro by standard laboratory protocols. The enzymatic activity index (EAI) was calculated for each enzyme in accordance to relevant protocols. Totally in eighty cases (32%), a Candida strain was isolated which found to be as 52 (65%) Candida albicans; 12 (15%) C. glabrata; 10 (12.5%) C. dubliniensis; 4 (5%) C. krusei, C. tropicalis and C. parapsilosis species (each=1; 1.3%). Among C. albicans strains, 89.1% produced all studied enzymes, while 86% of C. glabrata strains failed to produce proteinase and phospholipase. The EAIs in decreasing order were as hemolysin-β=0.2895, hemolysin-α=0.5420, esterase=0.5753, proteinase=0.7413, and phospholipase=0.7446, respectively. Activity of phospholipase, esterase and proteinase secreted by C. albicans and C. dubliniensis were significantly more than those released by C. glabrata and C. krusei, while 86% of C. glabrata strains did not show esterase activity. On the other hand, the activity rates of hemolysin α and β among all studied isolates were almost similar. In the present study, the prevalence of VVC among investigated women was higher than the previous report from Khuzestan but C. albicans has yet remained the predominant agent of VVC in this area. Given to the EAI, the virulence of C. albicans in VVC can be mediated by phospholipase, esterase and proteinases. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Improvements of Quantum Private Comparison Protocol Based on Cluster States
NASA Astrophysics Data System (ADS)
Zhou, Ming-Kuai
2018-01-01
Quantum private comparison aims to determine whether the secrets from two different users are equal or not by utilizing the laws of quantum mechanics. Recently, Sun and Long put forward a quantum private comparison (QPC) protocol by using four-particle cluster states (Int. J. Theor. Phys. 52, 212-218, 2013). In this paper, we investigate this protocol in depth, and suggest the corresponding improvements. Compared with the original protocol, the improved protocol has the following advantages: 1) it can release the requirements of authenticated classical channels and unitary operations; 2) it can prevent the malicious attack from the genuine semi-honest TP; 3) it can enhance the qubit efficiency.
Campos-Peña, E.; Martín-Nuñez, E.; Pulido-Reyes, G.; Martín-Padrón, J.; Caro-Carrillo, E.; Donate-Correa, J.; Lorenzo-Castrillejo, I.; Alcoba-Flórez, J.; Machín, F.
2014-01-01
We describe a new, efficient, sensitive, and fast single-tube multiple-PCR protocol for the identification of the most clinically significant Staphylococcus spp. and the simultaneous detection of the methicillin and mupirocin resistance loci. The protocol identifies at the species level isolates belonging to S. aureus, S. epidermidis, S. haemolyticus, S. hominis, S. lugdunensis, and S. saprophyticus. PMID:24829244
Şakalar, Çağrı; Kuk, Salih; Erensoy, Ahmet; Dağli, Adile Ferda; Özercan, İbrahim Hanifi; Çetınkaya, Ülfet; Yazar, Süleyman
2014-01-01
To develop a novel polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) protocol using a new genomic marker sequence and a novel set of restriction enzymes in order to detect and discriminate 2 Echinococcus species, E. granulosus and E. multilocularis, found in formalin-fixed paraffin-embedded (FFPE) human tissues. DNA was isolated from 11 FFPE human tissue samples positive for cystic echinococcosis or alveolar echinococcosis. A mitochondrial genomic marker region was amplified and sequenced using a novel primer pair and a new PCR-RFLP protocol was developed for the detection and discrimination of E. granulosus and E. multilocularis using a set of restriction enzymes including AccI, MboI, MboII, and TsoI. The selected marker region was amplified using DNA isolated from FFPE human tissue samples positive for cystic echinococcosis or alveolar echinococcosis and the discrimination of E. granulosus and E. multilocularis was accomplished by use of the novel PCR-RFLP method. In this PCR-RFLP protocol, use of any single restriction enzyme is enough for the discrimination of E. granulosus and E. multilocularis. The PCR-RFLP protocol can be potentially used for the discrimination of 5 other Echinococcus species: E. oligarthus, E. shiquicus, E. ortleppi, E. canadensis, and E. vogeli.
Xu, Fan; Zhen, Peng; Zheng, Yu; LIjuan, Feng; Aiting, Yang; Min, Cong; Hong, You; Jidong, Jia
2013-04-01
The aim of this study was to optimise a collagenase perfusion protocol for the isolation of a liver non-parenchymal cell (NPC) suspension enriched for Kupffer cells that reduced damage to F4/80 antigen cell surface expression to allow analysis by flow cytometry. Kupffer cell-enriched liver NPCs were isolated from C57BL/6 mice using different protocols. Flow cytometry was used to examine the effect of collagenase digestion on F4/80 expression on Kupffer cells, and results were represented by the percentage of F4/80 positive cells and by the F4/80 mean fluorescence intensity (MFI). The perfusion temperature, concentration of collagenase solution and total dosage of collagenase for liver perfusion influenced the effect of collagenase perfusion on the expression of F4/80 antigen on Kupffer cells. Collagenase perfusion at 28°C resulted in an increased percentage of F4/80 positive cells (P = 0.001) and MFI (P = 0.005) compared with 37°C. Perfusion with a total dose of 1.0 g/kg BW collagenase (using a 0.75 mg/mL solution) resulted in the highest percentage of F4/80 positive cells (P = 0.001) compared with 0.8 g/kg BW and 1.2 g/kg BW collagenase. Isolation of cells using the modified protocol resulted in a higher percentage of Kupffer cells (P < 0.001) and a higher MFI of F4/80 antigen (P < 0.001) compared with the common protocol. © 2013 International Federation for Cell Biology.
β-MSCs: successful fusion of MSCs with β-cells results in a β-cell like phenotype.
Azizi, Zahra; Lange, Claudia; Paroni, Federico; Ardestani, Amin; Meyer, Anke; Wu, Yonghua; Zander, Axel R; Westenfelder, Christof; Maedler, Kathrin
2016-08-02
Bone marrow mesenchymal stromal cells (MSC) have anti-inflammatory, anti-apoptotic and immunosuppressive properties and are a potent source for cell therapy. Cell fusion has been proposed for rapid generation of functional new reprogrammed cells. In this study, we aimed to establish a fusion protocol of bone marrow-derived human MSCs with the rat beta-cell line (INS-1E) as well as human isolated pancreatic islets in order to generate insulin producing beta-MSCs as a cell-based treatment for diabetes.Human eGFP+ puromycin+ MSCs were co-cultured with either stably mCherry-expressing rat INS-1E cells or human dispersed islet cells and treated with phytohemagglutinin (PHA-P) and polyethylene glycol (PEG) to induce fusion. MSCs and fused cells were selected by puromycin treatment.With an improved fusion protocol, 29.8 ± 2.9% of all MSCs were β-MSC heterokaryons based on double positivity for mCherry and eGFP.After fusion and puromycin selection, human NKX6.1 and insulin as well as rat Neurod1, Nkx2.2, MafA, Pdx1 and Ins1 mRNA were highly elevated in fused human MSC/INS-1E cells, compared to the mixed control population. Such induction of beta-cell markers was confirmed in fused human MSC/human dispersed islet cells, which showed elevated NEUROD1, NKX2.2, MAFA, PDX1 and insulin mRNA compared to the mixed control. Fused cells had higher insulin content and improved insulin secretion compared to the mixed control and insulin positive beta-MSCs also expressed nuclear PDX1. We established a protocol for fusion of human MSCs and beta cells, which resulted in a beta cell like phenotype. This could be a novel tool for cell-based therapies of diabetes.
Franco, Diogo; Franco, Talita; Schettino, Angélica Maria; Filho, João Medeiros Tavares; Vendramin, Fabiel Spani
2012-10-01
Plasma has been widely studied and used in many different situations to speed up healing with better tissue adherence and hemostasis. Research projects are now attempting to isolate platelet-rich plasma (PRP) and platelet-poor plasma (PPP), making better use of their properties, particularly during operations and for wounds that are slow to heal. In view of the wide diversity of industrial machines and extraction protocols, together with the variety of industrially produced biologic glues, this article suggests an option for obtaining PRP, PPP, and human thrombin for autologous use. A way of obtaining PRP, PPP, and thrombin is reproduced through a protocol defined and established by the authors. Autologous thrombin and plasma were obtained through the collection and successive centrifugation of ten whole blood samples, until the desired hemocomponents were isolated, followed by quantitative and qualitative analyses of the elements obtained. The mean platelet concentration obtained was 6.03 × 10(8) platelets/ml, with a mean thrombin concentration of 33.54 nM, both values compatible with reports in the literature when different protocols are applied. The protocol described is a good option for the preparation and application of PRP, PPP, and autologous thrombin, particularly as they can be obtained simultaneously, eliminating the possibilities of viral contamination and allergic reactions. Moreover, the cost of this procedure is low, it is easy to perform, and replicable. This journal requires that authors assign a level of evidence to each article.
Kresse, Stine H; Namløs, Heidi M; Lorenz, Susanne; Berner, Jeanne-Marie; Myklebost, Ola; Bjerkehagen, Bodil; Meza-Zepeda, Leonardo A
2018-01-01
Nucleic acid material of adequate quality is crucial for successful high-throughput sequencing (HTS) analysis. DNA and RNA isolated from archival FFPE material are frequently degraded and not readily amplifiable due to chemical damage introduced during fixation. To identify optimal nucleic acid extraction kits, DNA and RNA quantity, quality and performance in HTS applications were evaluated. DNA and RNA were isolated from five sarcoma archival FFPE blocks, using eight extraction protocols from seven kits from three different commercial vendors. For DNA extraction, the truXTRAC FFPE DNA kit from Covaris gave higher yields and better amplifiable DNA, but all protocols gave comparable HTS library yields using Agilent SureSelect XT and performed well in downstream variant calling. For RNA extraction, all protocols gave comparable yields and amplifiable RNA. However, for fusion gene detection using the Archer FusionPlex Sarcoma Assay, the truXTRAC FFPE RNA kit from Covaris and Agencourt FormaPure kit from Beckman Coulter showed the highest percentage of unique read-pairs, providing higher complexity of HTS data and more frequent detection of recurrent fusion genes. truXTRAC simultaneous DNA and RNA extraction gave similar outputs as individual protocols. These findings show that although successful HTS libraries could be generated in most cases, the different protocols gave variable quantity and quality for FFPE nucleic acid extraction. Selecting the optimal procedure is highly valuable and may generate results in borderline quality specimens.
Shu, Beatrice; Johnston, Tyler; Lindsey, Derek P; McAdams, Timothy R
2012-02-01
Enhancing anterior-posterior (AP) stability in acromioclavicular (AC) reconstruction may be advantageous. To compare the initial stability of AC reconstructions with and without augmentation by either (1) a novel "reverse" coracoacromial (CA) ligament transfer or (2) an intramedullary AC tendon graft. Reverse CA transfer will improve AP stability compared with isolated coracoclavicular (CC) reconstruction. Controlled laboratory study. Six matched pairs of cadaveric shoulders underwent distal clavicle resection and CC reconstruction. Displacement (mm) was measured during cyclic loading along AP (±25 N) and superior-inferior (SI; 10-N compression, 70-N tension) axes. Pairs were randomized to receive each augmentation and the same loading protocol applied. Reverse CA transfer (3.71 ± 1.3 mm, standard error of the mean [SEM]; P = .03) and intramedullary graft (3.41 ± 1.1 mm; P = .03) decreased AP translation compared with CC reconstruction alone. The SI displacement did not differ. Equivalence tests suggest no difference between augmentations in AP or SI restraint. Addition of either reverse CA transfer or intramedullary graft demonstrates improved AP restraint and provides similar SI stability compared with isolated CC reconstruction. Reverse CA ligament transfer may be a reasonable alternative to a free tendon graft to augment AP restraint in AC reconstruction.
Intelligent QoS routing algorithm based on improved AODV protocol for Ad Hoc networks
NASA Astrophysics Data System (ADS)
Huibin, Liu; Jun, Zhang
2016-04-01
Mobile Ad Hoc Networks were playing an increasingly important part in disaster reliefs, military battlefields and scientific explorations. However, networks routing difficulties are more and more outstanding due to inherent structures. This paper proposed an improved cuckoo searching-based Ad hoc On-Demand Distance Vector Routing protocol (CSAODV). It elaborately designs the calculation methods of optimal routing algorithm used by protocol and transmission mechanism of communication-package. In calculation of optimal routing algorithm by CS Algorithm, by increasing QoS constraint, the found optimal routing algorithm can conform to the requirements of specified bandwidth and time delay, and a certain balance can be obtained among computation spending, bandwidth and time delay. Take advantage of NS2 simulation software to take performance test on protocol in three circumstances and validate the feasibility and validity of CSAODV protocol. In results, CSAODV routing protocol is more adapt to the change of network topological structure than AODV protocol, which improves package delivery fraction of protocol effectively, reduce the transmission time delay of network, reduce the extra burden to network brought by controlling information, and improve the routing efficiency of network.
Two-party quantum key agreement protocols under collective noise channel
NASA Astrophysics Data System (ADS)
Gao, Hao; Chen, Xiao-Guang; Qian, Song-Rong
2018-06-01
Recently, quantum communication has become a very popular research field. The quantum key agreement (QKA) plays an important role in the field of quantum communication, based on its unconditional security in terms of theory. Among all kinds of QKA protocols, QKA protocols resisting collective noise are widely being studied. In this paper, we propose improved two-party QKA protocols resisting collective noise and present a feasible plan for information reconciliation. Our protocols' qubit efficiency has achieved 26.67%, which is the best among all the two-party QKA protocols against collective noise, thus showing that our protocol can improve the transmission efficiency of quantum key agreement.
Amini, Parisa; Ettlin, Julia; Opitz, Lennart; Clementi, Elena; Malbon, Alexandra; Markkanen, Enni
2017-08-23
Formalin-fixed paraffin embedded (FFPE) tissue constitutes a vast treasury of samples for biomedical research. Thus far however, extraction of RNA from FFPE tissue has proved challenging due to chemical RNA-protein crosslinking and RNA fragmentation, both of which heavily impact on RNA quantity and quality for downstream analysis. With very small sample sizes, e.g. when performing Laser-capture microdissection (LCM) to isolate specific subpopulations of cells, recovery of sufficient RNA for analysis with reverse-transcription quantitative PCR (RT-qPCR) or next-generation sequencing (NGS) becomes very cumbersome and difficult. We excised matched cancer-associated stroma (CAS) and normal stroma from clinical specimen of FFPE canine mammary tumours using LCM, and compared the commonly used protease-based RNA isolation procedure with an adapted novel technique that additionally incorporates a focused ultrasonication step. We successfully adapted a protocol that uses focused ultrasonication to isolate RNA from small amounts of deparaffinised, stained, clinical LCM samples. Using this approach, we found that total RNA yields could be increased by 8- to 12-fold compared to a commonly used protease-based extraction technique. Surprisingly, RNA extracted using this new approach was qualitatively at least equal if not superior compared to the old approach, as Cq values in RT-qPCR were on average 2.3-fold lower using the new method. Finally, we demonstrate that RNA extracted using the new method performs comparably in NGS as well. We present a successful isolation protocol for extraction of RNA from difficult and limiting FFPE tissue samples that enables successful analysis of small sections of clinically relevant specimen. The possibility to study gene expression signatures in specific small sections of archival FFPE tissue, which often entail large amounts of highly relevant clinical follow-up data, unlocks a new dimension of hitherto difficult-to-analyse samples which now become amenable for investigation.
Jozefowicz, Anna M; Matros, Andrea; Witzel, Katja; Mock, Hans-Peter
2018-01-01
Plasma membrane (PM) proteins are of special interest due to their function in exchanging material and information with the external environment as well as their role in cellular regulation. In quantitative proteomic studies PM proteins are underrepresented mostly because they constitute only small percent of all membrane proteins. Strong demand is placed on plasma membrane enrichment methods. For decades two-phase partitioning Dextran T500/PEG 3350 isolation protocols were applied for many different animal and plant species and also a variety of tissue types. The typical quantity of material used in the enrichment protocols is 10-30 g of fresh weight. The main difficulty of working with in vitro cultivated plants is the low amount of material, especially when roots are examined. In addition, roots are frequently characterized by low protein concentrations. Our protocol established for roots of in vitro cultivated potato plants is adjusted to amounts of fresh weight not exceeding 7.5 g and allows studying the plasma membrane proteome by LC-MS.
Shanks, O.C.; Sivaganesan, M.; Peed, L.; Kelty, C.A.; Blackwood, A.D.; Greene, M.R.; Noble, R.T.; Bushon, R.N.; Stelzer, E.A.; Kinzelman, J.; Anan'Eva, T.; Sinigalliano, C.; Wanless, D.; Griffith, J.; Cao, Y.; Weisberg, S.; Harwood, V.J.; Staley, C.; Oshima, K.H.; Varma, M.; Haugland, R.A.
2012-01-01
The application of quantitative real-time PCR (qPCR) technologies for the rapid identification of fecal bacteria in environmental waters is being considered for use as a national water quality metric in the United States. The transition from research tool to a standardized protocol requires information on the reproducibility and sources of variation associated with qPCR methodology across laboratories. This study examines interlaboratory variability in the measurement of enterococci and Bacteroidales concentrations from standardized, spiked, and environmental sources of DNA using the Entero1a and GenBac3 qPCR methods, respectively. Comparisons are based on data generated from eight different research facilities. Special attention was placed on the influence of the DNA isolation step and effect of simplex and multiplex amplification approaches on interlaboratory variability. Results suggest that a crude lysate is sufficient for DNA isolation unless environmental samples contain substances that can inhibit qPCR amplification. No appreciable difference was observed between simplex and multiplex amplification approaches. Overall, interlaboratory variability levels remained low (<10% coefficient of variation) regardless of qPCR protocol. ?? 2011 American Chemical Society.
Scalability enhancement of AODV using local link repairing
NASA Astrophysics Data System (ADS)
Jain, Jyoti; Gupta, Roopam; Bandhopadhyay, T. K.
2014-09-01
Dynamic change in the topology of an ad hoc network makes it difficult to design an efficient routing protocol. Scalability of an ad hoc network is also one of the important criteria of research in this field. Most of the research works in ad hoc network focus on routing and medium access protocols and produce simulation results for limited-size networks. Ad hoc on-demand distance vector (AODV) is one of the best reactive routing protocols. In this article, modified routing protocols based on local link repairing of AODV are proposed. Method of finding alternate routes for next-to-next node is proposed in case of link failure. These protocols are beacon-less, means periodic hello message is removed from the basic AODV to improve scalability. Few control packet formats have been changed to accommodate suggested modification. Proposed protocols are simulated to investigate scalability performance and compared with basic AODV protocol. This also proves that local link repairing of proposed protocol improves scalability of the network. From simulation results, it is clear that scalability performance of routing protocol is improved because of link repairing method. We have tested protocols for different terrain area with approximate constant node densities and different traffic load.
Optimisation of isolation of richly pure and homogeneous primary human colonic smooth muscle cells.
Tattoli, I; Corleto, V D; Taffuri, M; Campanini, N; Rindi, G; Caprilli, R; Delle Fave, G; Severi, C
2004-11-01
Inherent properties of gastrointestinal smooth muscle can be assessed using isolated cell suspensions. Currently available isolation techniques, based on short 2-h enzymatic digestion, however, present the disadvantage of low cellular yield with brief viability. These features are an important limiting factor especially in studies in humans in which tissue may not be available daily and mixing of samples is not recommended. To optimise the isolation procedure of cells from human colon to obtain a richly pure primary smooth muscle cell preparation. Slices of circular muscle layer, obtained from surgical specimens of human colon, were incubated overnight in Dulbecco's modified eagle's medium supplemented with antibiotics, foetal bovine serum, an ATP-regenerating system and collagenase. On the following day, digested muscle strips were suspended in HEPES buffer, and spontaneously dissociated smooth muscle cells were harvested and used either immediately or maintained in suspension for up to 72 h. Cell yield, purity, viability, contractile responses, associated intracellular calcium signals and RNA and protein extraction were evaluated and compared to cell suspensions obtained with the current short digestion protocol. The overnight isolation protocol offers the advantage of obtaining a pure, homogeneous, long-life viable cell suspension that maintains a fully differentiated smooth muscle phenotype unchanged for at least 72 h and that allows multiple functional/biochemical studies and efficient RNA extraction from a single human specimen.
Data dissemination using gossiping in wireless sensor networks
NASA Astrophysics Data System (ADS)
Medidi, Muralidhar; Ding, Jin; Medidi, Sirisha
2005-06-01
Disseminating data among sensors is a fundamental operation in energy-constrained wireless sensor networks. We present a gossip-based adaptive protocol for data dissemination to improve energy efficiency of this operation. To overcome the data implosion problems associated with dissemination operation, our protocol uses meta-data to name the data using high-level data descriptors and negotiation to eliminate redundant transmissions of duplicate data in the network. Further, we adapt the gossiping with data aggregation possibilities in sensor networks. We simulated our data dissemination protocol, and compared it to the SPIN protocol. We find that our protocol improves on the energy consumption by about 20% over others, while improving significantly over the data dissemination rate of gossiping.
Single-step isolation of extracellular vesicles by size-exclusion chromatography
Böing, Anita N.; van der Pol, Edwin; Grootemaat, Anita E.; Coumans, Frank A. W.; Sturk, Auguste; Nieuwland, Rienk
2014-01-01
Background Isolation of extracellular vesicles from plasma is a challenge due to the presence of proteins and lipoproteins. Isolation of vesicles using differential centrifugation or density-gradient ultracentrifugation results in co-isolation of contaminants such as protein aggregates and incomplete separation of vesicles from lipoproteins, respectively. Aim To develop a single-step protocol to isolate vesicles from human body fluids. Methods Platelet-free supernatant, derived from platelet concentrates, was loaded on a sepharose CL-2B column to perform size-exclusion chromatography (SEC; n=3). Fractions were collected and analysed by nanoparticle tracking analysis, resistive pulse sensing, flow cytometry and transmission electron microscopy. The concentrations of high-density lipoprotein cholesterol (HDL) and protein were measured in each fraction. Results Fractions 9–12 contained the highest concentrations of particles larger than 70 nm and platelet-derived vesicles (46%±6 and 61%±2 of totals present in all collected fractions, respectively), but less than 5% of HDL and less than 1% of protein (4.8%±1 and 0.65%±0.3, respectively). HDL was present mainly in fractions 18–20 (32%±2 of total), and protein in fractions 19–21 (36%±2 of total). Compared to the starting material, recovery of platelet-derived vesicles was 43%±23 in fractions 9–12, with an 8-fold and 70-fold enrichment compared to HDL and protein. Conclusions SEC efficiently isolates extracellular vesicles with a diameter larger than 70 nm from platelet-free supernatant of platelet concentrates. Application SEC will improve studies on the dimensional, structural and functional properties of extracellular vesicles. PMID:25279113
Oldrini, Guillaume; Fedida, Benjamin; Poujol, Julie; Felblinger, Jacques; Trop, Isabelle; Henrot, Philippe; Darai, Emile; Thomassin-Naggara, Isabelle
2017-10-01
To evaluate the added value of ULTRAFAST-MR sequence to an abbreviated FAST protocol in comparison with FULL protocol to distinguish benign from malignant lesions in a population of women, regardless of breast MR imaging indication. From March 10th to September 22th, 2014, we retrospectively included a total of 70 consecutive patients with 106 histologically proven lesions (58 malignant and 48 benign) who underwent breast MR imaging for preoperative breast staging (n=38), high-risk screening (n=7), problem solving (n=18), and nipple discharge (n=4) with 12 time resolved imaging of contrast kinetics (TRICKS) acquisitions during contrast inflow interleaved in a regular high-resolution dynamic MRI protocol (FULL protocol). Two readers scored MR exams as either positive or negative and described significant lesions according to Bi-RADS lexicon with a TRICKS images (ULTRAFAST), an abbreviated protocol (FAST) and all images (FULL protocol). Sensitivity, specificity, positive and negative predictive values, and accuracy were calculated for each protocol and compared with McNemar's test. For all readers, the combined FAST-ULTRAFAST protocol significantly improved the reading with a specificity of 83.3% and 70.8% in comparison with FAST protocol or FULL protocol, respectively, without change in sensitivity. By adding ULTRAFAST protocol to FAST protocol, readers 1 and 2 were able to correctly change the diagnosis in 22.9% (11/48) and 10.4% (5/48) of benign lesions, without missing any malignancy, respectively. Both interpretation and image acquisition times for combined FAST-ULTRAFAST protocol and FAST protocol were shorter compared to FULL protocol (p<0.001). Compared to FULL protocol, adding ULTRAFAST to FAST protocol improves specificity, mainly in correctly reclassifying benign masses and reducing interpretation and acquisition time, without decreasing sensitivity. Copyright © 2017 Elsevier B.V. All rights reserved.
Pasteran, Fernando; Gonzalez, Lisandro J; Albornoz, Ezequiel; Bahr, Guillermo; Vila, Alejandro J; Corso, Alejandra
2016-03-01
Accurate detection of carbapenemase-producing Gram-negative bacilli is of utmost importance for the control of nosocomial spread and the initiation of appropriate antimicrobial therapy. The modified Hodge test (MHT), a carbapenem inactivation assay, has shown poor sensitivity in detecting the worldwide spread of New Delhi metallo-β-lactamase (NDM). Recent studies demonstrated that NDM is a lipoprotein anchored to the outer membrane in Gram-negative bacteria, unlike all other known carbapenemases. Here we report that membrane anchoring of β-lactamases precludes detection of carbapenemase activity by the MHT. We also show that this limitation can be overcome by the addition of Triton X-100 during the test, which allows detection of NDM. We propose an improved version of the assay, called the Triton Hodge test (THT), which allows detection of membrane-bound carbapenemases with the addition of this nonionic surfactant. This test was challenged with a panel of 185 clinical isolates (145 carrying known carbapenemase-encoding genes and 40 carbapenemase nonproducers). The THT displayed test sensitivity of >90% against NDM-producing clinical isolates, while improving performance against other carbapenemases. Ertapenem provided the highest sensitivity (97 to 100%, depending on the type of carbapenemase), followed by meropenem (92.5 to 100%). Test specificity was not affected by the addition of Triton (87.5% and 92.5% with ertapenem and meropenem, respectively). This simple inexpensive test confers a large improvement to the sensitivity of the MHT for the detection of NDM and other carbapenemases. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
Isolation of Tonoplast Vesicles from Tomato Fruit Pericarp
Snowden, Christopher J.; Thomas, Benjamin; Baxter, Charles J.; Smith, J. Andrew C.; Sweetlove, Lee J.
2017-01-01
This protocol describes the isolation of tonoplast vesicles from tomato fruit. The vesicles isolated using this procedure are of sufficiently high purity for downstream proteomic analysis whilst remaining transport competent for functional assays. The methodology was used to study the transport of amino acids during tomato fruit ripening (Snowden et al., 2015) and based on the procedure used by Betty and Smith (Bettey and Smith, 1993). Such vesicles may be useful in further studies into the dynamic transfer of metabolites across the tonoplast for storage and metabolism during tomato fruit development. PMID:29085859
Improvement of "Novel Multiparty Quantum Key Agreement Protocol with GHZ States"
NASA Astrophysics Data System (ADS)
Gu, Jun; Hwang, Tzonelih
2017-10-01
Quantum key agreement (QKA) protocol is a method for negotiating a fair and secure key among mutually untrusted participants. Recently, Xu et al. (Quantum Inf. Process. 13:2587-2594, 2014) proposed a multi-party QKA protocol based on Greenberger-Horne-Zeilinger (GHZ) states. However, this study points out that Xu et al.'s protocol cannot provide the fairness property. That is, the last involved participant in the protocol can manipulate the final shared secret key without being detected by the other participants. Moreover, according to Yu et al.'s research (2015), Xu et al.'s protocol cannot avoid the public discussion attack too. To avoid these weaknesses, an improved QKA protocol is proposed.
StimDuino: an Arduino-based electrophysiological stimulus isolator.
Sheinin, Anton; Lavi, Ayal; Michaelevski, Izhak
2015-03-30
Electrical stimulus isolator is a widely used device in electrophysiology. The timing of the stimulus application is usually automated and controlled by the external device or acquisition software; however, the intensity of the stimulus is adjusted manually. Inaccuracy, lack of reproducibility and no automation of the experimental protocol are disadvantages of the manual adjustment. To overcome these shortcomings, we developed StimDuino, an inexpensive Arduino-controlled stimulus isolator allowing highly accurate, reproducible automated setting of the stimulation current. The intensity of the stimulation current delivered by StimDuino is controlled by Arduino, an open-source microcontroller development platform. The automatic stimulation patterns are software-controlled and the parameters are set from Matlab-coded simple, intuitive and user-friendly graphical user interface. The software also allows remote control of the device over the network. Electrical current measurements showed that StimDuino produces the requested current output with high accuracy. In both hippocampal slice and in vivo recordings, the fEPSP measurements obtained with StimDuino and the commercial stimulus isolators showed high correlation. Commercial stimulus isolators are manually managed, while StimDuino generates automatic stimulation patterns with increasing current intensity. The pattern is utilized for the input-output relationship analysis, necessary for assessment of excitability. In contrast to StimuDuino, not all commercial devices are capable for remote control of the parameters and stimulation process. StimDuino-generated automation of the input-output relationship assessment eliminates need for the current intensity manually adjusting, improves stimulation reproducibility, accuracy and allows on-site and remote control of the stimulation parameters. Copyright © 2015 Elsevier B.V. All rights reserved.
Yeliseev, Alexei; Zoubak, Lioudmila; Schmidt, Thomas G.M.
2017-01-01
Human cannabinoid receptor CB2 belongs to the class A of G protein-coupled receptor (GPCR). High resolution structural studies of CB2 require milligram quantities of purified, structurally intact protein. Here we describe an efficient protocol for purification of this protein using the Twin-Strep-tag/Strep-Tactin XT system. To improve the affinity of interaction of the recombinant CB2 with the resin, the double repeat of the Strep-tag was attached either to the N- or C-terminus of CB2 via a short linker. The CB2 was isolated at high purity from dilute solutions containing high concentrations of detergents, glycerol and salts, by capturing onto the Strep-Tactin XT resin, and was eluted from the resin under mild conditions upon addition of biotin. Surface plasmon resonance studies performed demonstrate the high affinity of interaction between the Twin-Strep-tag fused to the CB2 and Strep-Tactin XT with an estimated Kd in the low nanomolar range. The affinity of binding did not vary significantly in response to the position of the tag at either N- or C-termini of the fusion. The variation in the length of the linker between the double repeats of the Strep-tag from 6 to 12 amino acid residues did not significantly affect the binding. The novel purification protocol reported here enables efficient isolation of a recombinant GPCR expressed at low titers in host cells. This procedure is suitable for preparation of milligram quantities of stable isotope-labelled receptor for high-resolution NMR studies. PMID:27867058
Reich, Christine M; Raabe, Oksana; Wenisch, Sabine; Bridger, Philip S; Kramer, Martin; Arnhold, Stefan
2012-06-01
In the dog, mesenchymal stem cells (MSCs) have been shown to reside in the bone marrow (bone marrow-derived mesenchymal stem cells: BM-MSCs) as well as in the adipose tissue (adipose tissue-derived stem cells: ADSCs). Potential application fields for these multipotent MSCs in small animal practice are joint diseases as MSCs of both sources have shown to possess chondrogenic differentiation ability. However, it is not clear whether the chondrogenic differentiation potential of cells of these two distinct tissues is truly equal. Therefore, we compared MSCs of both origins in this study in terms of their chondrogenic differentiation ability and suitability for clinical application. BM-MSCs harvested from the femoral neck and ADSCs from intra-abdominal fat tissue were examined for their morphology, population doubling time (PDT) and CD90 surface antigen expression. RT-PCR served to assess expression of pluripotency marker Oct4 and early differentiation marker genes. Chondrogenic differentiation ability was compared and validated using histochemistry, transmission electron microscopy (TEM) and quantitative RT-PCR. Both cell populations presented a highly similar morphology and marker expression in an undifferentiated stage except that freshly isolated ADSCs demonstrated a significantly faster PDT than BM-MSCs. In contrast, BM-MSCs revealed a morphological superior cartilage formation by the production of a more abundant and structured hyaline matrix and higher expression of lineage specific genes under the applied standard differentiation protocol. However, further investigations are necessary in order to find out if chondrogenic differentiation can be improved in canine ADSCs using different protocols and/or supplements.
A Survey for Escherichia coli Virulence Factors in Asymptomatic Free-Ranging Parrots
Becker Saidenberg, André; Robaldo Guedes, Neiva Maria; Fernandes Seixas, Gláucia Helena; da Costa Allgayer, Mariangela; Pacífico de Assis, Erica; Fabio Silveira, Luis; Anne Melville, Priscilla; Benites, Nilson Roberti
2012-01-01
Parrots in captivity are frequently affected by Escherichia coli (E. coli) infections. The objective of this study was to collect information on the carrier state for E. coli pathotypes in asymptomatic free-ranging parrots. Cloacal swabs were collected from nestlings of Hyacinth, Lear's macaws and Blue-fronted Amazon parrots and tested by polymerase chain reaction (PCR) for virulence factors commonly found in enteropathogenic, avian pathogenic, and uropathogenic E. coli strains. In total, 44 samples were cultured and E. coli isolates were yielded, from which DNA was extracted and processed by PCR. Genes commonly found in APEC isolates from Blue-fronted Amazon parrots and Hyacinth macaws were expressed in 14 of these 44 samples. One atypical EPEC isolate was obtained from a sample from Lear's macaw. The most commonly found gene was the increased serum survival (iss) gene. This is the first report, that describes such pathotypes in asymptomatic free-living parrots. The findings of this study suggest the presence of a stable host/parasite relationship at the time of the sampling brings a new understanding to the role that E. coli plays in captive and wild parrots. Such information can be used to improve husbandry protocols as well as help conservation efforts of free-living populations. PMID:23738135
The hot oyster: levels of virulent Vibrio parahaemolyticus strains in individual oysters.
Klein, Savannah L; Lovell, Charles R
2017-02-01
Vibrio parahaemolyticus is the leading cause of seafood-associated gastroenteritis and is most commonly transmitted by raw oysters. Consequently, detection of virulent strains of this organism in oysters is a primary concern for seafood safety. Vibrio parahaemolyticus levels were determined in 110 individual oysters harvested from two sampling sites in SC, USA. The majority of oysters (98%) contained low levels of presumptive V. parahaemolyticus However, two healthy oysters contained presumptive V. parahaemolyticus numbers that were unusually high. These two 'hot' oysters contained levels of presumptive V. parahaemolyticus within the gills that were ∼100-fold higher than the average for other oysters collected at the same date and location. Current V. parahaemolyticus detection practices require homogenizing a dozen oysters pooled together to determine V. parahaemolyticus numbers, a procedure that would dilute out V. parahaemolyticus in these 'hot' oysters. This study demonstrates the variability of V. parahaemolyticus densities taken from healthy, neighboring individual oysters in the environment. Additionally, environmental V parahaemolyticus isolates were screened for the virulence-related genes, tdh and trh, using improved polymerase chain reaction primers and protocols. We detected these genes, previously thought to be rare in environmental isolates, in approximately half of the oyster isolates. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Adult multipotent stromal cell cryopreservation: Pluses and pitfalls
Duan, Wei; Hicok, Kevin
2017-01-01
Abstract Study and clinical testing of adult multipotent stromal cells (MSCs) are central to progressive improvements in veterinary regenerative medicine. Inherent limitations to long‐term culture preclude use for storage. Until cell line creation from primary isolates becomes routine, MSC stasis at cryogenic temperatures is required for this purpose. Many protocols and reagents, including cryoprotectants, used for veterinary MSCs are derived from those for human and rodent cells. Dissimilarities in cryopreservation strategies play a role in variable MSC behaviors. Familiarity with contemporary cryopreservation reagents and processes is essential to an appreciation of their impact on MSC survival and post‐cryopreservation behavior. In addition to these points, this review includes a brief history and description of current veterinary stem cell regulation. PMID:29023790
Groves, Maria AT; Amanuel, Lily; Campbell, Jamie I; Rees, D Gareth; Sridharan, Sudharsan; Finch, Donna K; Lowe, David C; Vaughan, Tristan J
2014-01-01
In vitro selection technologies are an important means of affinity maturing antibodies to generate the optimal therapeutic profile for a particular disease target. Here, we describe the isolation of a parent antibody, KENB061 using phage display and solution phase selections with soluble biotinylated human IL-1R1. KENB061 was affinity matured using phage display and targeted mutagenesis of VH and VL CDR3 using NNS randomization. Affinity matured VHCDR3 and VLCDR3 library blocks were recombined and selected using phage and ribosome display protocol. A direct comparison of the phage and ribosome display antibodies generated was made to determine their functional characteristics. PMID:24256948
Analyzing the effect of routing protocols on media access control protocols in radio networks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barrett, C. L.; Drozda, M.; Marathe, A.
2002-01-01
We study the effect of routing protocols on the performance of media access control (MAC) protocols in wireless radio networks. Three well known MAC protocols: 802.11, CSMA, and MACA are considered. Similarly three recently proposed routing protocols: AODV, DSR and LAR scheme 1 are considered. The experimental analysis was carried out using GloMoSim: a tool for simulating wireless networks. The main focus of our experiments was to study how the routing protocols affect the performance of the MAC protocols when the underlying network and traffic parameters are varied. The performance of the protocols was measured w.r.t. five important parameters: (i)more » number of received packets, (ii) average latency of each packet, (iii) throughput (iv) long term fairness and (v) number of control packets at the MAC layer level. Our results show that combinations of routing and MAC protocols yield varying performance under varying network topology and traffic situations. The result has an important implication; no combination of routing protocol and MAC protocol is the best over all situations. Also, the performance analysis of protocols at a given level in the protocol stack needs to be studied not locally in isolation but as a part of the complete protocol stack. A novel aspect of our work is the use of statistical technique, ANOVA (Analysis of Variance) to characterize the effect of routing protocols on MAC protocols. This technique is of independent interest and can be utilized in several other simulation and empirical studies.« less
A Method to Identify Nucleolus-Associated Chromatin Domains (NADs).
Carpentier, Marie-Christine; Picart-Picolo, Ariadna; Pontvianne, Frédéric
2018-01-01
The nuclear context needs to be taken into consideration to better understand the mechanisms shaping the epigenome and its organization, and therefore its impact on gene expression. For example, in Arabidopsis, heterochromatin is preferentially localized at the nuclear and the nucleolar periphery. Although chromatin domains associating with the nuclear periphery remain to be identified in plant cells, Nucleolus Associated chromatin Domains (NADs) can be identified thanks to a protocol allowing the isolation of pure nucleoli. We describe here the protocol enabling the identification of NADs in Arabidopsis. Providing the transfer of a nucleolus marker as described here in other crop species, this protocol is broadly applicable.
AIB-OR: improving onion routing circuit construction using anonymous identity-based cryptosystems.
Wang, Changji; Shi, Dongyuan; Xu, Xilei
2015-01-01
The rapid growth of Internet applications has made communication anonymity an increasingly important or even indispensable security requirement. Onion routing has been employed as an infrastructure for anonymous communication over a public network, which provides anonymous connections that are strongly resistant to both eavesdropping and traffic analysis. However, existing onion routing protocols usually exhibit poor performance due to repeated encryption operations. In this paper, we first present an improved anonymous multi-receiver identity-based encryption (AMRIBE) scheme, and an improved identity-based one-way anonymous key agreement (IBOWAKE) protocol. We then propose an efficient onion routing protocol named AIB-OR that provides provable security and strong anonymity. Our main approach is to use our improved AMRIBE scheme and improved IBOWAKE protocol in onion routing circuit construction. Compared with other onion routing protocols, AIB-OR provides high efficiency, scalability, strong anonymity and fault tolerance. Performance measurements from a prototype implementation show that our proposed AIB-OR can achieve high bandwidths and low latencies when deployed over the Internet.
AIB-OR: Improving Onion Routing Circuit Construction Using Anonymous Identity-Based Cryptosystems
Wang, Changji; Shi, Dongyuan; Xu, Xilei
2015-01-01
The rapid growth of Internet applications has made communication anonymity an increasingly important or even indispensable security requirement. Onion routing has been employed as an infrastructure for anonymous communication over a public network, which provides anonymous connections that are strongly resistant to both eavesdropping and traffic analysis. However, existing onion routing protocols usually exhibit poor performance due to repeated encryption operations. In this paper, we first present an improved anonymous multi-receiver identity-based encryption (AMRIBE) scheme, and an improved identity-based one-way anonymous key agreement (IBOWAKE) protocol. We then propose an efficient onion routing protocol named AIB-OR that provides provable security and strong anonymity. Our main approach is to use our improved AMRIBE scheme and improved IBOWAKE protocol in onion routing circuit construction. Compared with other onion routing protocols, AIB-OR provides high efficiency, scalability, strong anonymity and fault tolerance. Performance measurements from a prototype implementation show that our proposed AIB-OR can achieve high bandwidths and low latencies when deployed over the Internet. PMID:25815879
Choi, Younsung; Lee, Donghoon; Kim, Jiye; Jung, Jaewook; Nam, Junghyun; Won, Dongho
2014-01-01
Wireless sensor networks (WSNs) consist of sensors, gateways and users. Sensors are widely distributed to monitor various conditions, such as temperature, sound, speed and pressure but they have limited computational ability and energy. To reduce the resource use of sensors and enhance the security of WSNs, various user authentication protocols have been proposed. In 2011, Yeh et al. first proposed a user authentication protocol based on elliptic curve cryptography (ECC) for WSNs. However, it turned out that Yeh et al.'s protocol does not provide mutual authentication, perfect forward secrecy, and key agreement between the user and sensor. Later in 2013, Shi et al. proposed a new user authentication protocol that improves both security and efficiency of Yeh et al.'s protocol. However, Shi et al.'s improvement introduces other security weaknesses. In this paper, we show that Shi et al.'s improved protocol is vulnerable to session key attack, stolen smart card attack, and sensor energy exhausting attack. In addition, we propose a new, security-enhanced user authentication protocol using ECC for WSNs. PMID:24919012
Choi, Younsung; Lee, Donghoon; Kim, Jiye; Jung, Jaewook; Nam, Junghyun; Won, Dongho
2014-06-10
Wireless sensor networks (WSNs) consist of sensors, gateways and users. Sensors are widely distributed to monitor various conditions, such as temperature, sound, speed and pressure but they have limited computational ability and energy. To reduce the resource use of sensors and enhance the security of WSNs, various user authentication protocols have been proposed. In 2011, Yeh et al. first proposed a user authentication protocol based on elliptic curve cryptography (ECC) for WSNs. However, it turned out that Yeh et al.'s protocol does not provide mutual authentication, perfect forward secrecy, and key agreement between the user and sensor. Later in 2013, Shi et al. proposed a new user authentication protocol that improves both security and efficiency of Yeh et al.'s protocol. However, Shi et al.'s improvement introduces other security weaknesses. In this paper, we show that Shi et al.'s improved protocol is vulnerable to session key attack, stolen smart card attack, and sensor energy exhausting attack. In addition, we propose a new, security-enhanced user authentication protocol using ECC for WSNs.
An improved PRoPHET routing protocol in delay tolerant network.
Han, Seung Deok; Chung, Yun Won
2015-01-01
In delay tolerant network (DTN), an end-to-end path is not guaranteed and packets are delivered from a source node to a destination node via store-carry-forward based routing. In DTN, a source node or an intermediate node stores packets in buffer and carries them while it moves around. These packets are forwarded to other nodes based on predefined criteria and finally are delivered to a destination node via multiple hops. In this paper, we improve the dissemination speed of PRoPHET (probability routing protocol using history of encounters and transitivity) protocol by employing epidemic protocol for disseminating message m, if forwarding counter and hop counter values are smaller than or equal to the threshold values. The performance of the proposed protocol was analyzed from the aspect of delivery probability, average delay, and overhead ratio. Numerical results show that the proposed protocol can improve the delivery probability, average delay, and overhead ratio of PRoPHET protocol by appropriately selecting the threshold forwarding counter and threshold hop counter values.
Game-Based Rehabilitation for Myoelectric Prosthesis Control.
Prahm, Cosima; Vujaklija, Ivan; Kayali, Fares; Purgathofer, Peter; Aszmann, Oskar C
2017-02-09
A high number of upper extremity myoelectric prosthesis users abandon their devices due to difficulties in prosthesis control and lack of motivation to train in absence of a physiotherapist. Virtual training systems, in the form of video games, provide patients with an entertaining and intuitive method for improved muscle coordination and improved overall control. Complementary to established rehabilitation protocols, it is highly beneficial for this virtual training process to start even before receiving the final prosthesis, and to be continued at home for as long as needed. The aim of this study is to evaluate (1) the short-term effects of a commercially available electromyographic (EMG) system on controllability after a simple video game-based rehabilitation protocol, and (2) different input methods, control mechanisms, and games. Eleven able-bodied participants with no prior experience in EMG control took part in this study. Participants were asked to perform a surface EMG test evaluating their provisional maximum muscle contraction, fine accuracy and isolation of electrode activation, and endurance control over at least 300 seconds. These assessments were carried out (1) in a Pregaming session before interacting with three EMG-controlled computer games, (2) in a Postgaming session after playing the games, and (3) in a Follow-Up session two days after the gaming protocol to evaluate short-term retention rate. After each game, participants were given a user evaluation survey for the assessment of the games and their input mechanisms. Participants also received a questionnaire regarding their intrinsic motivation (Intrinsic Motivation Inventory) at the end of the last game. Results showed a significant improvement in fine accuracy electrode activation (P<.01), electrode separation (P=.02), and endurance control (P<.01) from Pregaming EMG assessments to the Follow-Up measurement. The deviation around the EMG goal value diminished and the opposing electrode was activated less frequently. Participants had the most fun playing the games when collecting items and facing challenging game play. Most upper limb amputees use a 2-channel myoelectric prosthesis control. This study demonstrates that this control can be effectively trained by employing a video game-based rehabilitation protocol. ©Cosima Prahm, Ivan Vujaklija, Fares Kayali, Peter Purgathofer, Oskar C Aszmann. Originally published in JMIR Serious Games (http://games.jmir.org), 09.02.2017.
Lagares, Antonio; Agaras, Betina; Bettiol, Marisa P; Gatti, Blanca M; Valverde, Claudio
2015-07-01
Species-specific genetic markers are crucial to develop faithful and sensitive molecular methods for the detection and identification of Pseudomonas aeruginosa (Pa). We have previously set up a PCR-RFLP protocol targeting oprF, the gene encoding the genus-specific outer membrane porin F, whose strong conservation and marked sequence diversity allowed detection and differentiation of environmental isolates (Agaras et al., 2012). Here, we evaluated the ability of the PCR-RFLP assay to genotype clinical isolates previously identified as Pa by conventional microbiological methods within a collection of 62 presumptive Pa isolates from different pediatric clinical samples and different sections of the Hospital de Niños "Sor María Ludovica" from La Plata, Argentina. All isolates, but one, gave an oprF amplicon consistent with that from reference Pa strains. The sequence of the smaller-sized amplicon revealed that the isolate was in fact a mendocina Pseudomonas strain. The oprF RFLP pattern generated with TaqI or HaeIII nucleases matched those of reference Pa strains for 59 isolates (96%). The other two Pa isolates (4%) revealed a different RFLP pattern based on HaeIII digestion, although oprF sequencing confirmed that Pa identification was correct. We next tested the effectiveness of the PCR-RFLP to detect pseudomonads on clinical samples of pediatric fibrocystic patients directly without sample cultivation. The expected amplicon and its cognate RFLP profile were obtained for all samples in which Pa was previously detected by cultivation-dependent methods. Altogether, these results provide the basis for the application of the oprF PCR-RFLP protocol to directly detect and identify Pa and other non-Pa pseudomonads in fibrocystic clinical samples. Copyright © 2015 Elsevier B.V. All rights reserved.
Kloß, Sandra; Lorenz, Björn; Dees, Stefan; Labugger, Ines; Rösch, Petra; Popp, Jürgen
2015-11-01
Lower respiratory tract infections are the fourth leading cause of death worldwide. Here, a timely identification of the causing pathogens is crucial to the success of the treatment. Raman spectroscopy allows for quick identification of bacterial cells without the need for time-consuming cultivation steps, which is the current gold standard to detect pathogens. However, before Raman spectroscopy can be used to identify pathogens, they have to be isolated from the sample matrix, i.e., sputum in case of lower respiratory tract infections. In this study, we report an isolation protocol for single bacterial cells from sputum samples for Raman spectroscopic identification. Prior to the isolation, a liquefaction step using the proteolytic enzyme mixture Pronase E is required in order to deal with the high viscosity of sputum. The extraction of the bacteria was subsequently performed via different filtration and centrifugation steps, whereby isolation ratios between 46 and 57 % were achieved for sputa spiked with 6·10(7) to 6·10(4) CFU/mL of Staphylococcus aureus. The compatibility of such a liquefaction and isolation procedure towards a Raman spectroscopic classification was shown for five different model species, namely S. aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, Klebsiella pneumoniae, and Pseudomonas aeruginosa. A classification of single-cell Raman spectra of these five species with an accuracy of 98.5 % could be achieved on the basis of a principal component analysis (PCA) followed by a linear discriminant analysis (LDA). These classification results could be validated with an independent test dataset, where 97.4 % of all spectra were identified correctly. Graphical Abstract Development of an isolation protocol of bacterial cells out of sputum samples followed by Raman spectroscopic measurement and species identification using chemometrical models.
Screening protocol for Torulopsis (Candida) glabrata.
Land, G; Burke, J; Shelby, C; Rhodes, J; Collett, J; Bennett, I; Johnson, J
1996-01-01
A screening test has been developed for the presumptive identification of Torulopsis (Candida) glabrata from other common clinical isolates of yeast-like fungi. An interlaboratory comparison of a protocol consisting of morphology on cornmeal Tween 80 agar and trehalose fermentation at 42 degrees C was successful in differentiating T. glabrata from other taxa that are frequent or possible clinical isolates. The screening results for 517 clinical yeast isolates, 241 of which were T. glabrata, were compared with their final identification via commercial systems (API20C Yeast Identification System [bioMERIEUX, Hazelwood, Mo.] and Rapid Yeast Identification Panel [Dade Microscan, Sacramento, Calif.]). The trehalose screening test has a sensitivity and a specificity of 97.8 and 95.8%, respectively, and a positive predictive value of 97.4% and a negative predictive value of 96.5%. Overall, the trehalose screen had an efficiency rating of 93.9% for ruling in or out T. glabrata. Since T. glabrata represents a substantial part of the workload in a clinical laboratory, a significant reduction in direct and indirect costs should be realized. PMID:8862605
An efficient protocol for tissue sampling and DNA isolation from the stem bark of Leguminosae trees.
Novaes, R M L; Rodrigues, J G; Lovato, M B
2009-02-03
Traditionally, molecular studies of plant species have used leaves as the source of DNA. However, sampling leaves from tall tree species can be quite difficult and expensive. We developed a sequence of procedures for using stem bark as a source of DNA from Leguminosae trees of the Atlantic Forest and the Cerrado. Leguminosae is an important species-rich family in these two highly diverse and endangered biomes. A modified CTAB protocol for DNA isolation is described, and details of the procedures for sampling and storage of the bark are given. The procedures were initially developed for three species, and then their applicability for 15 other species was evaluated. DNA of satisfactory quality was obtained from the bark of all species. The amounts of DNA obtained from leaves were slightly higher than from bark samples, while its purity was the same. Storing the bark frozen or by drying in silica gel yielded similar results. Polymerase chain reaction amplification worked for both plastid and nuclear genomes. This alternative for isolating DNA from bark samples of trees facilitates field work with these tree species.
An optimized high quality male DNA extraction from spermatophores in open thelycum shrimp species.
Planella, Laia; Heras, Sandra; Vera, Manuel; García-Marín, José-Luis; Roldán, María Inés
2017-09-01
The crucial step of most of the current genetic studies is the extraction of DNA of sufficient quantity and quality. Several genomic DNA isolation methods have been described to successfully obtain male DNA from shrimp species. However, all current protocols require invasive handling methods with males for DNA isolation. Using Aristeus antennatus as a model we tested a reliable non-invasive differential DNA extraction method to male DNA isolation from spermatophores attached to female thelycum. The present protocol provides high quality and quantity DNA for polymerase chain reaction amplification and male genotyping. This new approach could be useful to experimental shrimp culture to select sires with relevant genetic patterns for selective breeding programs. More importantly, it can be applied to identify the mating pairs and male structure in wild populations of species as A. antennatus, where males are often difficult to capture. Our method could be also valuable for biological studies on other spermatophore-using species, such as myriapods, arachnids and insects. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.
Recovery of high-quality RNA from laser capture microdissected human and rodent pancreas.
Butler, Alexandra E; Matveyenko, Aleksey V; Kirakossian, David; Park, Johanna; Gurlo, Tatyana; Butler, Peter C
Laser capture microdissection (LCM) is a powerful method to isolate specific populations of cells for subsequent analysis such as gene expression profiling, for example, microarrays or ribonucleic (RNA)-Seq. This technique has been applied to frozen as well as formalin-fixed, paraffin-embedded (FFPE) specimens with variable outcomes regarding quality and quantity of extracted RNA. The goal of the study was to develop the methods to isolate high-quality RNA from islets of Langerhans and pancreatic duct glands (PDG) isolated by LCM. We report an optimized protocol for frozen sections to minimize RNA degradation and maximize recovery of expected transcripts from the samples using quantitative real-time polymerase chain reaction (RT-PCR) by adding RNase inhibitors at multiple steps during the experiment. This technique reproducibly delivered intact RNA (RIN values 6-7). Using quantitative RT-PCR, the expected profiles of insulin, glucagon, mucin6 (Muc6), and cytokeratin-19 (CK-19) mRNA in PDGs and pancreatic islets were detected. The described experimental protocol for frozen pancreas tissue might also be useful for other tissues with moderate to high levels of intrinsic ribonuclease (RNase) activity.
Woltjen, Knut; Ito, Kenichi; Tsuzuki, Teruhisa; Rancourt, Derrick E
2008-01-01
In recent years, methods to address the simplification of targeting vector (TV) construction have been developed and validated. Based on in vivo recombination in Escherichia coli, these protocols have reduced dependence on restriction endonucleases, allowing the fabrication of complex TV constructs with relative ease. Using a methodology based on phage-plasmid recombination, we have developed a comprehensive TV construction protocol dubbed Orpheus recombination (ORE). The ORE system addresses all necessary requirements for TV construction; from the isolation of genespecific regions of homology to the deposition of selection/disruption cassettes. ORE makes use of a small recombination plasmid, which bears positive and negative selection markers and a cloned homologous "probe" region. This probe plasmid may be introduced into and excised from phage-borne murine genomic clones by two rounds of single crossover recombination. In this way, desired clones can be specifically isolated from a heterogeneous library of phage. Furthermore, if the probe region contains a designed mutation, it may be deposited seamlessly into the genomic clone. The complete removal of operational sequences allows unlimited repetition of the procedure to customize and finalize TVs within a few weeks. Successful gene-specific clone isolation, point mutations, large deletions, cassette insertions, and finally coincident clone isolation and mutagenesis have all been demonstrated with this method.
Schalch, Barbara; Bader, Lutz; Schau, Hans-Peter; Bergmann, Rolf; Rometsch, Andrea; Maydl, Gertraud; Keßler, Silvia
2003-01-01
In 1998, 21 inhabitants of a German nursing home fell ill with acute gastroenteritis after consumption of minced beef heart (P. Graf and L. Bader, Epidemiol. Bull. 41:327-329, 2000). Two residents died during hospital treatment. Seventeen Clostridium perfringens strains were collected from two different dishes and from patients' stool samples and autopsy materials. A majority of these isolates was not typeable by restriction fragment length polymorphism-pulsed-field gel electrophoresis (PFGE). Subsequent ribotyping of C. perfringens distinguished four different groups. The same ribopattern was detected in a minced beef heart dish, in autopsy material from the two deceased patients, and additionally in stool samples from six further residents who had fallen ill with diarrhea. Three further ribopatterns from food and autopsy materials could be differentiated. As chromosomal macrorestriction with subsequent PFGE is generally regarded more useful than ribotyping for molecular strain analysis, four selected isolates were lysed in parallel with a standard protocol and two nucleases inhibiting modifications. Neither of these methods could differentiate all of the isolates. These results suggest that PFGE with the current standard protocols is not able to characterize all C. perfringens isolates from food-borne disease investigations and that ribotyping is still a helpful method for molecular identification of clonal relationships. PMID:12574310
Calculations for reproducible autologous skin cell-spray grafting.
Esteban-Vives, Roger; Young, Matthew T; Zhu, Toby; Beiriger, Justin; Pekor, Chris; Ziembicki, Jenny; Corcos, Alain; Rubin, Peter; Gerlach, Jörg C
2016-12-01
Non-cultured, autologous cell-spray grafting is an alternative to mesh grafting for larger partial- and deep partial-thickness burn wounds. The treatment uses a suspension of isolated cells, from a patient's donor site skin tissue, and cell-spray deposition onto the wound that facilitates re-epithelialization. Existing protocols for therapeutic autologous skin cell isolation and cell-spray grafting have defined the donor site area to treatment area ratio of 1:80, substantially exceeding the coverage of conventional mesh grafting. However, ratios of 1:100 are possible by maximizing the wound treatment area with harvested cells from a given donor site skin tissue according to a given burn area. Although cell isolation methods are very well described in the literature, a rational approach addressing critical aspects of these techniques are of interest in planning clinical study protocols. We considered in an experimental study the cell yield as a function of the donor site skin tissue, the cell density for spray grafting, the liquid spray volume, the sprayed distribution area, and the percentage of surface coverage. The experimental data was then used for the development of constants and mathematical equations to give a rationale for the cell isolation and cell-spray grafting processes and in planning for clinical studies. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.
An affordable method to obtain cultured endothelial cells from peripheral blood
Bueno-Betí, Carlos; Novella, Susana; Lázaro-Franco, Macarena; Pérez-Cremades, Daniel; Heras, Magda; Sanchís, Juan; Hermenegildo, Carlos
2013-01-01
The culture of endothelial progenitor cells (EPC) provides an excellent tool to research on EPC biology and vascular regeneration and vasculogenesis. The use of different protocols to obtain EPC cultures makes it difficult to obtain comparable results in different groups. This work offers a systematic comparison of the main variables of most commonly used protocols for EPC isolation, culture and functional evaluation. Peripheral blood samples from healthy individuals were recovered and mononuclear cells were cultured. Different recovery and culture conditions were tested: blood volume, blood anticoagulant, coating matrix and percentage of foetal bovine serum (FBS) in culture media. The success of culture procedure, first colonies of endothelial cells appearance time, correlation with number of circulating EPC (cEPC) and functional comparison with human umbilical vein endothelial cells (HUVEC) were studied. The use of heparin, a minimum blood volume of 30 ml, fibronectin as a coating matrix and endothelial growing media-2 supplemented with 20% FBS increased the success of obtaining EPC cultures up to 80% of the processed samples while reducing EPC colony appearance mean time to a minimum of 13 days. Blood samples exhibiting higher cEPC numbers resulted in reduced EPC colony appearance mean time. Cells isolated by using this combination were endothelial cell-like EPCs morphological and phenotypically. Functionally, cultured EPC showed decreased growing and vasculogenic capacity when compared to HUVEC. Thus, above-mentioned conditions allow the isolation and culture of EPC with smaller blood volumes and shorter times than currently used protocols. PMID:24118735
Montes-Borrego, Miguel; Lopes, Joao R S; Jiménez-Díaz, Rafael M; Landa, Blanca B
2015-03-01
Two haplotypes of Xylella fastidiosa subsp. pauca (Xfp) that correlated with their host of origin were identified in a collection of 90 isolates infecting citrus and coffee plants in Brazil, based on a single-nucleotide polymorphism in the gyrB sequence. A new single-nucleotide primer extension (SNuPE) protocol was designed for rapid identification of Xfp according to the host source. The protocol proved to be robust for the prediction of the Xfp host source in blind tests using DNA from cultures of the bacterium, infected plants, and insect vectors allowed to feed on Xfp-infected citrus plants. AMOVA and STRUCTURE analyses of microsatellite data separated most Xfp populations on the basis of their host source, indicating that they were genetically distinct. The combined use of the SNaPshot protocol and three previously developed multilocus SSR markers showed that two haplotypes and distinct isolates of Xfp infect citrus and coffee in Brazil and that multiple, genetically different isolates can be present in a single orchard or infect a single tree. This combined approach will be very useful in studies of the epidemiology of Xfp-induced diseases, host specificity of bacterial genotypes, the occurrence of Xfp host jumping, vector feeding habits, etc., in economically important cultivated plants or weed host reservoirs of Xfp in Brazil and elsewhere. Copyright© by the Spanish Society for Microbiology and Institute for Catalan Studies.
Efficient isolation method for high-quality genomic DNA from cicada exuviae.
Nguyen, Hoa Quynh; Kim, Ye Inn; Borzée, Amaël; Jang, Yikweon
2017-10-01
In recent years, animal ethics issues have led researchers to explore nondestructive methods to access materials for genetic studies. Cicada exuviae are among those materials because they are cast skins that individuals left after molt and are easily collected. In this study, we aim to identify the most efficient extraction method to obtain high quantity and quality of DNA from cicada exuviae. We compared relative DNA yield and purity of six extraction protocols, including both manual protocols and available commercial kits, extracting from four different exoskeleton parts. Furthermore, amplification and sequencing of genomic DNA were evaluated in terms of availability of sequencing sequence at the expected genomic size. Both the choice of protocol and exuvia part significantly affected DNA yield and purity. Only samples that were extracted using the PowerSoil DNA Isolation kit generated gel bands of expected size as well as successful sequencing results. The failed attempts to extract DNA using other protocols could be partially explained by a low DNA yield from cicada exuviae and partly by contamination with humic acids that exist in the soil where cicada nymphs reside before emergence, as shown by spectroscopic measurements. Genomic DNA extracted from cicada exuviae could provide valuable information for species identification, allowing the investigation of genetic diversity across consecutive broods, or spatiotemporal variation among various populations. Consequently, we hope to provide a simple method to acquire pure genomic DNA applicable for multiple research purposes.
Bacterial Infections in Children With Acute Myeloid Leukemia Receiving Ciprofloxacin Prophylaxis.
Al Omar, Suha; Anabtawi, Nadine; Al Qasem, Wiam; Rihani, Rawad
2017-04-01
The aim of the study was to describe the incidence and type of bacterial infections associated with the use of ciprofloxacin prophylaxis as single agent in pediatric patients with acute myeloid leukemia (AML). This was a retrospective review of all patients with AML, who were treated according to the AML02 protocol between 2011 and 2015. The medical records were reviewed for any positive cultures from the initiation of the protocol until death or protocol discontinuation. Patient demographics, type of infections, type of isolated bacteria, and intensive care unit admissions were recorded. A total of 50 patients were evaluated, who were of a mean age of 8 years±5.1 (SD). We identified 77 episodes of bacterial infections in 42 (84%) patients. Among those bacterial infections, 73 episodes were with bacteremia and included 45 (62%) gram-positive bacterial infections, 24 (33%) gram-negative bacterial infections, and 4 (6%) mixed gram-negative and gram-positive bacterial infections. Coagulase-negative Staphylococcus and Viridans streptococci were the most commonly isolated bacteria in 33% and 30% of the episodes, respectively. Seventeen (45%) patients with bacteremia required intensive care unit admission. A high rate of bacterial infection was detected in patients who received the AML02 protocol, mainly gram-positive bacterial infections. The prophylactic regimen should be reconsidered for its efficacy, and other antibacterial prophylaxis may be used.
Romay-Tallon, Raquel; Rivera-Baltanas, Tania; Allen, Josh; Olivares, Jose M; Kalynchuk, Lisa E; Caruncho, Hector J
2017-01-01
The pattern of serotonin transporter clustering on the plasma membrane of lymphocytes extracted from human whole blood samples has been identified as a putative biomarker of therapeutic efficacy in major depression. Here we evaluated the possibility of performing a similar analysis using blood smears obtained from rats, and from control human subjects and depression patients. We hypothesized that we could optimize a protocol to make the analysis of serotonin protein clustering in blood smears comparable to the analysis of serotonin protein clustering using isolated lymphocytes. Our data indicate that blood smears require a longer fixation time and longer times of incubation with primary and secondary antibodies. In addition, one needs to optimize the image analysis settings for the analysis of smears. When these steps are followed, the quantitative analysis of both the number and size of serotonin transporter clusters on the plasma membrane of lymphocytes is similar using both blood smears and isolated lymphocytes. The development of this novel protocol will greatly facilitate the collection of appropriate samples by eliminating the necessity and cost of specialized personnel for drawing blood samples, and by being a less invasive procedure. Therefore, this protocol will help us advance the validation of membrane protein clustering in lymphocytes as a biomarker of therapeutic efficacy in major depression, and bring it closer to its clinical application.
Peters, Derek T; Henderson, Christopher A; Warren, Curtis R; Friesen, Max; Xia, Fang; Becker, Caroline E; Musunuru, Kiran; Cowan, Chad A
2016-05-01
Hepatocyte-like cells (HLCs) are derived from human pluripotent stem cells (hPSCs) in vitro, but differentiation protocols commonly give rise to a heterogeneous mixture of cells. This variability confounds the evaluation of in vitro functional assays performed using HLCs. Increased differentiation efficiency and more accurate approximation of the in vivo hepatocyte gene expression profile would improve the utility of hPSCs. Towards this goal, we demonstrate the purification of a subpopulation of functional HLCs using the hepatocyte surface marker asialoglycoprotein receptor 1 (ASGR1). We analyzed the expression profile of ASGR1-positive cells by microarray, and tested their ability to perform mature hepatocyte functions (albumin and urea secretion, cytochrome activity). By these measures, ASGR1-positive HLCs are enriched for the gene expression profile and functional characteristics of primary hepatocytes compared with unsorted HLCs. We have demonstrated that ASGR1-positive sorting isolates a functional subpopulation of HLCs from among the heterogeneous cellular population produced by directed differentiation. © 2016. Published by The Company of Biologists Ltd.
Hemming, Victoria; Walshe, Terry V; Hanea, Anca M; Fidler, Fiona; Burgman, Mark A
2018-01-01
Natural resource management uses expert judgement to estimate facts that inform important decisions. Unfortunately, expert judgement is often derived by informal and largely untested protocols, despite evidence that the quality of judgements can be improved with structured approaches. We attribute the lack of uptake of structured protocols to the dearth of illustrative examples that demonstrate how they can be applied within pressing time and resource constraints, while also improving judgements. In this paper, we demonstrate how the IDEA protocol for structured expert elicitation may be deployed to overcome operational challenges while improving the quality of judgements. The protocol was applied to the estimation of 14 future abiotic and biotic events on the Great Barrier Reef, Australia. Seventy-six participants with varying levels of expertise related to the Great Barrier Reef were recruited and allocated randomly to eight groups. Each participant provided their judgements using the four-step question format of the IDEA protocol ('Investigate', 'Discuss', 'Estimate', 'Aggregate') through remote elicitation. When the events were realised, the participant judgements were scored in terms of accuracy, calibration and informativeness. The results demonstrate that the IDEA protocol provides a practical, cost-effective, and repeatable approach to the elicitation of quantitative estimates and uncertainty via remote elicitation. We emphasise that i) the aggregation of diverse individual judgements into pooled group judgments almost always outperformed individuals, and ii) use of a modified Delphi approach helped to remove linguistic ambiguity, and further improved individual and group judgements. Importantly, the protocol encourages review, critical appraisal and replication, each of which is required if judgements are to be used in place of data in a scientific context. The results add to the growing body of literature that demonstrates the merit of using structured elicitation protocols. We urge decision-makers and analysts to use insights and examples to improve the evidence base of expert judgement in natural resource management.
Rosanowski, S M; Rogers, C W; Cogger, N; Benschop, J; Stevenson, M A
2012-11-01
A survey was conducted to investigate biosecurity practices on non-commercial horse properties, to describe the number of visits by horse professionals and any protocols that visitors were required to follow before interacting with resident horses. Data were collected in November 2009 during a cross-sectional study of non-commercial horse properties, in New Zealand, selected using generalised random-tessellated stratified design and a self-administered postal questionnaire. Data were described and the associations between property-level factors and biosecurity practices were analysed using logistic regression analysis. In total there were 791 respondents from non-commercial horse properties, of which 660 (83%) answer at least one question relating to biosecurity practices. Of the respondents, 95% had at least one biosecurity practice for arriving horses. Only 31% of properties isolated horses for more than four days, and few respondents checked for pyrexia or other clinical signs of infectious disease in new horses. Moving horses from a property was associated with the implementation of biosecurity practices and practices specific to the clinical signs of respiratory disease. Overall, 79% of properties had horse professional's visit, but only 33% of respondents reported biosecurity protocols for these visitors. Most properties had some knowledge about newly arriving horses, but the effectiveness of these practices for biosecurity were questionable, as few practices would stop disease spread to resident horses. Horse professionals are likely candidates for disease spread due to contact with horses, limited visitor protocols and the frequency of visits. The development of a plan to improve biosecurity for endemic and exotic disease is recommended. Copyright © 2012 Elsevier B.V. All rights reserved.
Sachs, Peter B; Hunt, Kelly; Mansoubi, Fabien; Borgstede, James
2017-02-01
Building and maintaining a comprehensive yet simple set of standardized protocols for a cross-sectional image can be a daunting task. A single department may have difficulty preventing "protocol creep," which almost inevitably occurs when an organized "playbook" of protocols does not exist and individual radiologists and technologists alter protocols at will and on a case-by-case basis. When multiple departments or groups function in a large health system, the lack of uniformity of protocols can increase exponentially. In 2012, the University of Colorado Hospital formed a large health system (UCHealth) and became a 5-hospital provider network. CT and MR imaging studies are conducted at multiple locations by different radiology groups. To facilitate consistency in ordering, acquisition, and appearance of a given study, regardless of location, we minimized the number of protocols across all scanners and sites of practice with a clinical indication-driven protocol selection and standardization process. Here we review the steps utilized to perform this process improvement task and insure its stability over time. Actions included creation of a standardized protocol template, which allowed for changes in electronic storage and management of protocols, designing a change request form, and formation of a governance structure. We utilized rapid improvement events (1 day for CT, 2 days for MR) and reduced 248 CT protocols into 97 standardized protocols and 168 MR protocols to 66. Additional steps are underway to further standardize output and reporting of imaging interpretation. This will result in an improved, consistent radiologist, patient, and provider experience across the system.
Security of the arbitrated quantum signature protocols revisited
NASA Astrophysics Data System (ADS)
Kejia, Zhang; Dan, Li; Qi, Su
2014-01-01
Recently, much attention has been paid to the study of arbitrated quantum signature (AQS). Among these studies, the cryptanalysis of some AQS protocols and a series of improved ideas have been proposed. Compared with the previous analysis, we present a security criterion, which can judge whether an AQS protocol is able to prevent the receiver (i.e. one participant in the signature protocol) from forging a legal signature. According to our results, it can be seen that most AQS protocols which are based on the Zeng and Keitel (ZK) model are susceptible to a forgery attack. Furthermore, we present an improved idea of the ZK protocol. Finally, some supplement discussions and several interesting topics are provided.
The impact of protocol on nurses' role stress: a longitudinal perspective.
Dodd-McCue, Diane; Tartaglia, Alexander; Veazey, Kenneth W; Streetman, Pamela S
2005-04-01
The study examined the impact of a protocol directed at increasing organ donation on the role stress and work attitudes of critical care nurses involved in potential organ donation cases. The research examined whether the protocol could positively affect nurses' perceptions of role stress, and if so, could the work environment improvements be sustained over time. The Family Communication Coordinator (FCC) protocol promotes effective communication during potential organ donation cases using a multidisciplinary team approach. Previous research found it associated with improved donation outcomes and with improved perceptions of role stress by critical care nurses. However, the previous study lacked methodological rigor necessary to determine causality and sustainability over time. The study used a quasi-experimental prospective longitudinal design. The sample included critical care nurses who had experience with potential organ donation cases with the protocol. Survey data were collected at 4 points over 2 years. Surveys used previously validated and reliable measures of role stress (role ambiguity, role conflict, role overload) and work attitudes (commitment, satisfaction). Interviews supplemented these data. The nurses' perceptions of role stress associated with potential organ donation cases dramatically dropped after the protocol was implemented. All measures of role stress, particularly role ambiguity and role conflict, showed statistically significant and sustained improvement. Nurses' professional, unit, and hospital commitment and satisfaction reflect an increasingly positive workplace. The results demonstrate that the FCC protocol positively influenced the workplace through its impact on role stress over the first 2 years following its implementation. The findings suggest that similar protocols may be appropriate in improving the critical care environment by reducing the stress and uncertainty of professionals involved in other end-of-life situations. However, the most striking implication relates to the reality of the workplace: meeting the goals of improved patient care outcomes and those of improving the healthcare work environment are not mutually exclusive and may be mutually essential.
Localization of mRNA in vertebrate axonal compartments by in situ hybridization.
Sotelo-Silveira, José Roberto; Calliari, Aldo; Kun, Alejandra; Elizondo, Victoria; Canclini, Lucía; Sotelo, José Roberto
2011-01-01
The conclusive demonstration of RNA in vertebrate axons by in situ hybridization (ISH) has been elusive. We review the most important reasons for difficulties, including low concentration of axonal RNAs, localization in specific cortical domains, and the need to isolate axons. We demonstrate the importance of axon micro-dissection to obtain a whole mount perspective of mRNA distribution in the axonal territory. We describe a protocol to perform fluorescent ISH in isolated axons and guidelines for the preservation of structural and molecular integrity of cortical RNA-containing domains (e.g., Periaxoplasmic Ribosomal Plaques, or PARPs) in isolated axoplasm.
Control of epidemics on complex networks: Effectiveness of delayed isolation
NASA Astrophysics Data System (ADS)
Pereira, Tiago; Young, Lai-Sang
2015-08-01
We study isolation as a means to control epidemic outbreaks in complex networks, focusing on the consequences of delays in isolating infected nodes. Our analysis uncovers a tipping point: if infected nodes are isolated before a critical day dc, the disease is effectively controlled, whereas for longer delays the number of infected nodes climbs steeply. We show that dc can be estimated explicitly in terms of network properties and disease parameters, connecting lowered values of dc explicitly to heterogeneity in degree distribution. Our results reveal also that initial delays in the implementation of isolation protocols can have catastrophic consequences in heterogeneous networks. As our study is carried out in a general framework, it has the potential to offer insight and suggest proactive strategies for containing outbreaks of a range of serious infectious diseases.
Eye movement training is most effective when it involves a task-relevant sensorimotor decision.
Fooken, Jolande; Lalonde, Kathryn M; Mann, Gurkiran K; Spering, Miriam
2018-04-01
Eye and hand movements are closely linked when performing everyday actions. We conducted a perceptual-motor training study to investigate mutually beneficial effects of eye and hand movements, asking whether training in one modality benefits performance in the other. Observers had to predict the future trajectory of a briefly presented moving object, and intercept it at its assumed location as accurately as possible with their finger. Eye and hand movements were recorded simultaneously. Different training protocols either included eye movements or a combination of eye and hand movements with or without external performance feedback. Eye movement training did not transfer across modalities: Irrespective of feedback, finger interception accuracy and precision improved after training that involved the hand, but not after isolated eye movement training. Conversely, eye movements benefited from hand movement training or when external performance feedback was given, thus improving only when an active interceptive task component was involved. These findings indicate only limited transfer across modalities. However, they reveal the importance of creating a training task with an active sensorimotor decision to improve the accuracy and precision of eye and hand movements.
Kabat, Susan M; Dick, Christopher W; Hunter, Mark D
2010-05-01
Microsatellite primers were developed for the common milkweed, Asclepias syriaca L., to assist in genet identification and the analysis of spatial genetic structure. Using an enrichment cloning protocol, eight microsatellite loci were isolated and characterized in a Michigan population of A. syriaca. The primers amplified di- and trinucleotide repeats with 4-13 alleles per locus. The primers will be useful for studies of clonality and gene flow in natural populations.
Cortical Isolation from Xenopus laevis Oocytes and Eggs.
Sive, Hazel L; Grainger, Robert M; Harland, Richard M
2007-06-01
INTRODUCTIONIn Xenopus laevis, the cortex is the layer of gelatinous cytoplasm that lies just below the plasma membrane of the egg. Rotation of the cortex relative to the deeper cytoplasm soon after fertilization is intimately linked to normal dorsal axis specification. The cortex can be dissected from the egg to analyze its composition and activity or to clone associated RNAs. This protocol describes a procedure for isolating the vegetal cortex of the fertilized egg.
Carpinella, Ilaria; Cattaneo, Davide; Bertoni, Rita; Ferrarin, Maurizio
2012-05-01
In this pilot study, we compared two protocols for robot-based rehabilitation of upper limb in multiple sclerosis (MS): a protocol involving reaching tasks (RT) requiring arm transport only and a protocol requiring both objects' reaching and manipulation (RMT). Twenty-two MS subjects were assigned to RT or RMT group. Both protocols consisted of eight sessions. During RT training, subjects moved the handle of a planar robotic manipulandum toward circular targets displayed on a screen. RMT protocol required patients to reach and manipulate real objects, by moving the robotic arm equipped with a handle which left the hand free for distal tasks. In both trainings, the robot generated resistive and perturbing forces. Subjects were evaluated with clinical and instrumental tests. The results confirmed that MS patients maintained the ability to adapt to the robot-generated forces and that the rate of motor learning increased across sessions. Robot-therapy significantly reduced arm tremor and improved arm kinematics and functional ability. Compared to RT, RMT protocol induced a significantly larger improvement in movements involving grasp (improvement in Grasp ARAT sub-score: RMT 77.4%, RT 29.5%, p=0.035) but not precision grip. Future studies are needed to evaluate if longer trainings and the use of robotic handles would significantly improve also fine manipulation.
Microenvironments and Signaling Pathways Regulating Early Dissemination, Dormancy, and Metastasis
2015-09-01
late disseminated tumor cells. Progress has also been made in devising a sorting protocol to isolate CFP+/HER2+ DTCs from lungs and CTCs in the MMTV...early dissemination of pre- malignant MECs. We further hypothesize that after extravasation at S-TMEM, in order to exit dormancy a stable S-TMEM...mentioned in section SA1.2, and the optimization of these protocols is underway. Aim 2.1 requires that we validate the components of the TMEM in the
Detection Protocols for West Nile Virus in Mosquitoes, Birds, and Nonhuman Mammals.
Kauffman, Elizabeth B; Franke, Mary A; Kramer, Laura D
2016-01-01
West Nile virus is the most widespread mosquito-borne virus in the world, and the most common cause of encephalitis in the USA. Surveillance for this medially important mosquito-borne pathogen is an important part of public health practice. Here we present protocols for testing environmental samples such as mosquitoes, nonvertebrate mammals, and birds for this virus, including RT-PCR, virus isolation in cell culture, and antigenic assays, as well as serologic assays for antibody detection.
Study of intelligent building system based on the internet of things
NASA Astrophysics Data System (ADS)
Wan, Liyong; Xu, Renbo
2017-03-01
In accordance with the problem such as isolated subsystems, weak system linkage and expansibility of the bus type buildings management system, this paper based on the modern intelligent buildings has studied some related technologies of the intelligent buildings and internet of things, and designed system architecture of the intelligent buildings based on the Internet of Things. Meanwhile, this paper has also analyzed wireless networking modes, wireless communication protocol and wireless routing protocol of the intelligent buildings based on the Internet of Things.
Musante, Luca; Tataruch-Weinert, Dorota; Kerjaschki, Dontscho; Henry, Michael; Meleady, Paula; Holthofer, Harry
2017-01-01
Urinary extracellular vesicles (UEVs) appear an ideal source of biomarkers for kidney and urogenital diseases. The majority of protocols designed for their isolation are based on differential centrifugation steps. However, little is still known of the type and amount of vesicles left in the supernatant. Here we used an isolation protocol for UEVs which uses hydrostatic filtration dialysis as first pre-enrichment step, followed by differential centrifugation. Transmission electron microscopy (TEM), mass spectrometry (MS), western blot, ELISA assays and tuneable resistive pulse sensing (TRPS) were used to characterise and quantify UEVs in the ultracentrifugation supernatant. TEM showed the presence of a variety of small size vesicles in the supernatant while protein identification by MS matched accurately with the protein list available in Vesiclepedia. Screening and relative quantification for specific vesicle markers showed that the supernatant was preferentially positive for CD9 and TSG101. ELISA tests for quantification of exosome revealed that 14%, was left in the supernatant with a particle diameter of 110 nm and concentration of 1.54 × 10 10 /ml. Here we show a comprehensive characterisation of exosomes and other small size urinary vesicles which the conventional differential centrifugation protocol may lose.
Musante, Luca; Tataruch-Weinert, Dorota; Kerjaschki, Dontscho; Henry, Michael; Meleady, Paula; Holthofer, Harry
2017-01-01
ABSTRACT Urinary extracellular vesicles (UEVs) appear an ideal source of biomarkers for kidney and urogenital diseases. The majority of protocols designed for their isolation are based on differential centrifugation steps. However, little is still known of the type and amount of vesicles left in the supernatant. Here we used an isolation protocol for UEVs which uses hydrostatic filtration dialysis as first pre-enrichment step, followed by differential centrifugation. Transmission electron microscopy (TEM), mass spectrometry (MS), western blot, ELISA assays and tuneable resistive pulse sensing (TRPS) were used to characterise and quantify UEVs in the ultracentrifugation supernatant. TEM showed the presence of a variety of small size vesicles in the supernatant while protein identification by MS matched accurately with the protein list available in Vesiclepedia. Screening and relative quantification for specific vesicle markers showed that the supernatant was preferentially positive for CD9 and TSG101. ELISA tests for quantification of exosome revealed that 14%, was left in the supernatant with a particle diameter of 110 nm and concentration of 1.54 × 1010/ml. Here we show a comprehensive characterisation of exosomes and other small size urinary vesicles which the conventional differential centrifugation protocol may lose. PMID:28326167
Purification of circular DNA using benzoylated naphthoylated DEAE-cellulose.
Gamper, H; Lehman, N; Piette, J; Hearst, J E
1985-04-01
Un-nicked circular DNA can be separated from protein, RNA, and other DNA in a simple three-step protocol consisting of exonuclease III digestion, extraction with benzoylated naphthoylated DEAE-cellulose (BND cellulose) in 1 M NaCl, and alcohol precipitation of the remaining supercoiled DNA. Exonuclease III treatment introduces single-stranded regions into contaminating linear and nicked circular DNA. This DNA, together with most RNA and protein, is adsorbed onto BND cellulose leaving form I DNA in solution. The protocol can be used to purify analytical as well as preparative amounts of supercoiled DNA. This procedure is a substitute for cesium chloride-ethidium bromide gradient ultracentrifugation and gives a comparable yield of pure form I DNA. Other classes of DNA can be isolated by changing the pretreatment step. Selective digestion of linear DNA with lambda exonuclease permits the isolation of both nicked circular and supercoiled DNA while brief heat-induced or alkali-induced denaturation leads to the recovery of rapidly reannealing DNA. In large-scale purifications, the basic protocol is usually preceded by one or more BND cellulose extractions in 1 M NaCl to remove contaminants absorbing UV or inhibiting exonuclease III.
Improving generalized inverted index lock wait times
NASA Astrophysics Data System (ADS)
Borodin, A.; Mirvoda, S.; Porshnev, S.; Ponomareva, O.
2018-01-01
Concurrent operations on tree like data structures is a cornerstone of any database system. Concurrent operations intended for improving read\\write performance and usually implemented via some way of locking. Deadlock-free methods of concurrency control are known as tree locking protocols. These protocols provide basic operations(verbs) and algorithm (ways of operation invocations) for applying it to any tree-like data structure. These algorithms operate on data, managed by storage engine which are very different among RDBMS implementations. In this paper, we discuss tree locking protocol implementation for General inverted index (Gin) applied to multiversion concurrency control (MVCC) storage engine inside PostgreSQL RDBMS. After that we introduce improvements to locking protocol and provide usage statistics about evaluation of our improvement in very high load environment in one of the world’s largest IT company.
Pogliani, Simona; Pellegatta, Serena; Antozzi, Carlo; Baggi, Fulvio; Gellera, Cinzia; Pollo, Bianca; Parati, Eugenio A.; Finocchiaro, Gaetano; Frigerio, Simona
2012-01-01
Immune-based treatments represent a promising new class of therapy designed to boost the immune system to specifically eradicate malignant cells. Immunotherapy may generate specific anti-tumor immune responses, and dendritic cells (DC), professional antigen-presenting cells, are widely used in experimental cancer immunotherapy. Several reports describe methods for the generation of mature, antigen-pulsed DC for clinical use. Improved quality and standardization are desirable to obtain GMP-compliant protocols. In this study we describe the generation of DC from 31 Glioblastoma (GB) patients starting from their monocytes isolated by immunomagnetic CD14 selection using the CliniMACS® device. Upon differentiation of CD14+ with IL-4 and GM-CSF, DC were induced to maturation with TNF-α, PGE2, IL-1β, and IL-6. Whole tumor lysate was obtained, for the first time, in a closed system using the semi-automated dissociator GentleMACS®. The yield of proteins improved by 130% compared to the manual dissociation method. Interestingly the Mean Fluorescence Intensity for CD83 increased significantly in DC pulsed with “new method” lysate compared to DC pulsed with “classical method” lysate. Our results indicate that immunomagnetic isolation of CD14+ monocytes using the CliniMACS® device and their pulsing with whole tumor lysate proteins is a suitable method for clinical-scale generation of high quality, functional DC under GMP-grade conditions. PMID:23284979
Azzolini, Michela; Tosi, Emanuele; Faccio, Stefano; Lorenzini, Marilinda; Torriani, Sandra; Zapparoli, Giacomo
2013-09-01
In order to improve the quality of Italian passito wine, produced from withered grapes that can be naturally infected by noble rot, in this study, a novel protocol was developed to select suitable cultures of both Botrytis cinerea to infect grapes (as noble rot) and of Saccharomyces cerevisiae to ferment grapes. A total of 16 B. cinerea isolated from withered grapes were typified by RAPD-PCR, and three representative strains were selected for physiological characterization. The strains showed different mycelial growth and enzymatic activities (i.e. polygalacturonase, protease, and laccase). A total of 15 yeasts were isolated from spontaneous fermented wines, these were identified as S. cerevisiae, and typified at strain level. Seven strains were selected according to RAPD-PCR profiles and tested for their fermentation performances. The effects of B. cinerea and S. cerevisiae cultures on the aroma profile of sweet style wine were preliminary evaluated fermenting artificially botrytized grapes induced with B. cinerea infection. The combination of selected fungi affected the aroma profile of wine according to the variation of the content of important molecules (i.e. alcohols, esters, and lactones). This study has provided valuable information to develop new natural cultures destined to induce grape botrytization and manage fermentation in passito winemaking. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.
Deliberate Design of TiO2 Nanostructures towards Superior Photovoltaic Cells.
Sun, Ziqi; Liao, Ting; Sheng, Liyuan; Kou, Liangzhi; Kim, Jung Ho; Dou, Shi Xue
2016-08-01
TiO2 nanostructures are being sought after as flexibly utilizable building blocks for the fabrication of the mesoporous thin-film photoelectrodes that are the heart of the third-generation photovoltaic devices, such as dye-sensitized solar cells (DSSCs), quantum-dot-sensitized solar cells (QDSSCs), and the recently promoted perovskite-type solar cells. Here, we report deliberate tailoring of TiO2 nanostructures for superior photovoltaic cells. Morphology engineering of TiO2 nanostructures is realized by designing synthetic protocols in which the precursor hydrolysis, crystal growth, and oligomer self-organization are precisely controlled. TiO2 nanostructures in forms varying from isolated nanocubes, nanorods, and cross-linked nanorods to complex hierarchical structures and shape-defined mesoporous micro-/nanostructures were successfully synthesized. The photoanodes made from the shape-defined mesoporous TiO2 microspheres and nanospindles presented superior performances, owing to the well-defined overall shapes and the inner ordered nanochannels, which allow not only a high amount of dye uptake, but also improved visible-light absorption. This study provides a new way to seek an optimal synthetic protocol to meet the required functionality of the nanomaterials. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Bausinger, Julia; Speit, Günter
2016-09-01
The comet assay is frequently used in human biomonitoring for the detection of exposure to genotoxic agents. Peripheral blood samples are most frequently used and tested either as whole blood or after isolation of lymphocytes (i.e. peripheral blood mononuclear cells, PBMC). To investigate a potential impact of lymphocyte isolation on induced DNA damage in human blood samples, we exposed blood ex vivo to mutagens with different modes of genotoxic action. The comet assay was performed either directly with whole blood at the end of the exposure period or with lymphocytes isolated directly after exposure. In addition to the recommended standard protocol for lymphocyte isolation, a shortened protocol was established to optimise the isolation procedure. The results indicate that the effects of induced DNA strand breaks and alkali-labile sites induced by ionising radiation and alkylants, respectively, are significantly reduced in isolated lymphocytes. In contrast, oxidative DNA base damage (induced by potassium bromate) and stable bulky adducts (induced by benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide; BPDE) seem to be less affected. Our findings suggest that in vivo-induced DNA damage might also be reduced in isolated lymphocytes in comparison with the whole blood depending of the types of DNA damage induced. Because only small genotoxic effects can generally be expected in human biomonitoring studies with the comet assay after occupational and environmental exposure to genotoxic agents, any loss might be relevant and should be avoided. The possibility of such effects and their potential impact on variability of comet assay results in human biomonitoring should be considered when performing or evaluating such kind of studies. © The Author 2016. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Zhang, Ying; Kuang, Min; Zhang, Lijuan; Yang, Pengyuan; Lu, Haojie
2013-06-04
In light of the significance of glycosylation for wealthy biological events, it is important to prefractionate glycoproteins/glycopeptides from complex biological samples. Herein, we reported a novel protocol of solid-phase extraction of glycopeptides through a reductive amination reaction by employing the easily accessible 3-aminopropyltriethoxysilane (APTES)-functionalized magnetic nanoparticles. The amino groups from APTES, which were assembled onto the surface of the nanoparticles through a one-step silanization reaction, could conjugate with the aldehydes from oxidized glycopeptides and, therefore, completed the extraction. To the best of our knowledge, this is the first example of applying the reductive amination reaction into the isolation of glycopeptides. Due to the elimination of the desalting step, the detection limit of glycopeptides was improved by 2 orders of magnitude, compared to the traditional hydrazide chemistry-based solid phase extraction, while the extraction time was shortened to 4 h, suggesting the high sensitivity, specificity, and efficiency for the extraction of N-linked glycopeptides by this method. In the meantime, high selectivity toward glycoproteins was also observed in the separation of Ribonuclease B from the mixtures contaminated with bovine serum albumin. What's more, this technique required significantly less sample volume, as demonstrated in the successful mapping of glycosylation of human colorectal cancer serum with the sample volume as little as 5 μL. Because of all these attractive features, we believe that the innovative protocol proposed here will shed new light on the research of glycosylation profiling.
High-Throughput Fluorescence-Based Isolation of Live C. elegans Larvae
Fernandez, Anita G.; Bargmann, Bastiaan O. R.; Mis, Emily K.; Edgley, Mark. L.; Birnbaum, Kenneth D.; Piano, Fabio
2017-01-01
For the nematode Caenorhabditis elegans, automated selection of animals of specific genotypes from a mixed pool has become essential for genetic interaction or chemical screens. To date, such selection has been accomplished using specialized instruments. However, access to such dedicated equipment is not common. Here we describe live animal fluorescence-activated cell sorting (laFACS), a protocol for automatic selection of live L1 animals using a standard FACS. We show that a FACS can be used for the precise identification of GFP-expressing and non-GFP-expressing sub-populations and can accomplish high-speed sorting of live animals. We have routinely collected 100,000 or more homozygotes from a mixed starting population within two hours and with greater than ninety-nine percent purity. The sorted animals continue to develop normally, making this protocol ideally suited for the isolation of terminal mutants for use in genetic interaction or chemical genetic screens. PMID:22814389
Measurement of Basal and Forskolin-stimulated Lipolysis in Inguinal Adipose Fat Pads.
Baskaran, Padmamalini; Thyagarajan, Baskaran
2017-07-21
Lipolysis is a process by which the lipid stored as triglycerides in adipose tissues are hydrolyzed into glycerol and fatty acids. This article describes the method for the measurement of basal and forskolin (FSK)-stimulated lipolysis in the inguinal fat pads isolated from wild type mice fed either normal chow diet (NCD), high fat diet (HFD) or a high fat diet containing 0.01% of capsaicin (CAP; transient receptor potential vanilloid subfamily 1 (TRPV1) agonist) for 32 weeks. The method described here for performing ex vivo lipolysis is adopted from Schweiger et al. 1 We present a detailed protocol for measuring glycerol levels by UV-Visible (UV/VIS) spectrophotometry. The method described here can be used to successfully isolate inguinal fat pads for lipolysis measurements to obtain consistent results. The protocol described for inguinal fat pads can readily be extended to measure lipolysis in other tissues.
2007-01-01
Teleost gut associated lymphoid tissue (GALT) consists of leucocyte populations located both intraepithelially and in the lamina propria with no structural organization. The present study aims to assess different protocols for the isolation of GALT cells from an important fish species in the Mediterranean aquaculture, the gilthead seabream. Mechanical, chemical and enzymatic treatments were assayed. Nylon wool columns and continuous density gradients were used for further separation of cell subpopulations. Light microscopy and flow cytometry showed that the highest density band (HD) consisted of a homogeneous lymphocytic population, whereas the intermediate density band (ID) corresponded to epithelial and secretory cells and some lymphocytes. Respiratory burst activity of total cell suspensions revealed very low numbers of potential phagocytic cells, reflecting results from light microscopy and reports in other teleost species. The present data set up the basis for future functional characterization of GALT in seabream. PMID:18213363
Novel methodology to isolate microplastics from vegetal-rich samples.
Herrera, Alicia; Garrido-Amador, Paloma; Martínez, Ico; Samper, María Dolores; López-Martínez, Juan; Gómez, May; Packard, Theodore T
2018-04-01
Microplastics are small plastic particles, globally distributed throughout the oceans. To properly study them, all the methodologies for their sampling, extraction, and measurement should be standardized. For heterogeneous samples containing sediments, animal tissues and zooplankton, several procedures have been described. However, definitive methodologies for samples, rich in algae and plant material, have not yet been developed. The aim of this study was to find the best extraction protocol for vegetal-rich samples by comparing the efficacies of five previously described digestion methods, and a novel density separation method. A protocol using 96% ethanol for density separation was better than the five digestion methods tested, even better than using H 2 O 2 digestion. As it was the most efficient, simple, safe and inexpensive method for isolating microplastics from vegetal rich samples, we recommend it as a standard separation method. Copyright © 2018 Elsevier Ltd. All rights reserved.
Methods for isolation of marine-derived endophytic fungi and their bioactive secondary products.
Kjer, Julia; Debbab, Abdessamad; Aly, Amal H; Proksch, Peter
2010-03-01
Marine-derived fungi have been shown in recent years to produce a plethora of new bioactive secondary metabolites, some of them featuring new carbon frameworks hitherto unprecedented in nature. These compounds are of interest as new lead structures for medicine as well as for plant protection. The aim of this protocol is to give a detailed description of methods useful for the isolation and cultivation of fungi associated with various marine organisms (sponges, algae and mangrove plants) for the extraction, characterization and structure elucidation of biologically active secondary metabolites produced by these marine-derived endophytic fungi, and for the preliminary evaluation of their pharmacological properties based on rapid 'in house' screening systems. Some results exemplifying the positive outcomes of the protocol are given at the end. From sampling in marine environment to completion of the structure elucidation and bioactivity screening, a period of at least 3 months has to be scheduled.
Molecular Typing of Borrelia burgdorferi
Wang, Guiqing; Liveris, Dionysios; Mukherjee, Priyanka; Jungnick, Sabrina; Margos, Gabriele; Schwartz, Ira
2015-01-01
Borrelia burgdorferi sensu lato is a group of spirochetes belonging to the genus Borrelia in the family of Spirochaetaceae. The spirochete is transmitted between reservoirs and hosts by ticks of the family Ixodidae. Infection with B. burgdorferi in humans causes Lyme disease or Lyme borreliosis. Currently, 20 Lyme disease-associated Borrelia species and more than 20 relapsing fever-associated Borrelia species have been described. Identification and differentiation of different Borrelia species and strains is largely dependent on analyses of their genetic characteristics. A variety of molecular techniques have been described for Borrelia isolate speciation, molecular epidemiology, and pathogenicity studies. In this unit, we focus on three basic protocols, PCR-RFLP-based typing of the rrs-rrlA and rrfA-rrlB ribosomal spacer, ospC typing, and MLST. These protocols can be employed alone or in combination for characterization of B. burgdorferi isolates or directly on uncultivated organisms in ticks, mammalian host reservoirs, and human clinical specimens. PMID:25082003
NASA Technical Reports Server (NTRS)
1990-01-01
Despite a vast amount of research, little is known concerning the effect of group structure, and individuals' understanding of that structure, on conflict in Antarctic groups. The overall objective of the research discussed is to determine the interrelationships of group structure, social cognition, and group function and conflict in isolated and extreme environments. In the two decades following WWII, a large body of research focused on the physiological, psychological, and social psychological factors affecting the functioning of individuals and groups in a variety of extreme and isolated environments in both the Arctic and Antarctic. There are two primary reasons for further research of this type. First, Antarctic polar stations are considered to be natural laboratories for the social and behavioral sciences and provide an opportunity to address certain theoretical and empirical questions concerned with agreement and conflict in social groups in general and group behavior in extreme, isolated environments in particular. Recent advances in the analysis of social networks and intracultural variation have improved the methods and have shifted the theoretical questions. The research is motivated by three classes of questions: (1) What are the characteristics of the social relations among individuals working and living together in extreme and isolated environments?; (2) What do individuals understand about their group, how does that understanding develop, and how is it socially distributed?; and (3) What is the relationship between that understanding and the functioning of the social group? Answers to these questions are important if we are to advance our knowledge of how individuals and groups adapt to extreme environments. Second, although Antarctic winter-over candidates may be evaluated as qualified on the basis of individual characteristics, they may fail to adapt because of certain characteristics of the social group. Consequently, the ability of winter-over-groups to adapt to these extreme conditions has varied dramatically from year to year. In the past, differences in personality, background, and social status have led to conflicts between individuals or cliques precipitating, in turn, an overall decline in morale, failure to accomplish work tasks, and increases in insomnia, depression, anxiety, and alcohol abuse. A better understanding of the role of group structure and social cognition in processes of group adaptation and conflict in Antarctica would contribute towards the revision of existing screening methods, potentially leading to a reduction of group conflict and improved performance of scientific research and support activities. An improved screening protocol for the Antarctic would also have applications for other isolated environments such as scientific outposts and the proposed NASA space station. In sum, this research will (1) contribute significantly to our theoretical understanding of the role of social structure and cognition in the functioning of groups in isolation; (2) complement current work on health and adaptation in polar environments; and (3) provide for models of the formation of group structure that will aid in the development of improved procedures for assembling groups for the Antarctic and other isolated environments (e.g., space stations).
Biosca, Elena G.; Flores, Raquel; Santander, Ricardo D.; Díez-Gil, José Luis; Barreno, Eva
2016-01-01
Lichens, self-supporting mutualistic associations between a fungal partner and one or more photosynthetic partners, also harbor non-photosynthetic bacteria. The diversity and contribution of these bacteria to the functioning of lichen symbiosis have recently begun to be studied, often by culture-independent techniques due to difficulties in their isolation and culture. However, culturing as yet unculturable lichenic bacteria is critical to unravel their potential functional roles in lichen symbiogenesis, to explore and exploit their biotechnological potential and for the description of new taxa. Our objective was to improve the recovery of lichen associated bacteria by developing novel isolation and culture approaches, initially using the lichen Pseudevernia furfuracea. We evaluated the effect of newly developed media enriched with novel lichen extracts, as well as the influence of thalli washing time and different disinfection and processing protocols of thalli. The developed methodology included: i) the use of lichen enriched media to mimic lichen nutrients, supplemented with the fungicide natamycin; ii) an extended washing of thalli to increase the recovery of ectolichenic bacteria, thus allowing the disinfection of thalli to be discarded, hence enhancing endolichenic bacteria recovery; and iii) the use of an antioxidant buffer to prevent or reduce oxidative stress during thalli disruption. The optimized methodology allowed significant increases in the number and diversity of culturable bacteria associated with P. furfuracea, and it was also successfully applied to the lichens Ramalina farinacea and Parmotrema pseudotinctorum. Furthermore, we provide, for the first time, data on the abundance of culturable ecto- and endolichenic bacteria that naturally colonize P. furfuracea, R. farinacea and P. pseudotinctorum, some of which were only able to grow on lichen enriched media. This innovative methodology is also applicable to other microorganisms inhabiting these and other lichen species. PMID:27494030
Kizilbash, Quratulain; Jost, Kenneth; Armitige, Lisa; Griffith, David E; Dunbar, Denise; Seaworth, Barbara
2017-01-01
Abstract Background Non tuberculous mycobacteria (NTM) are widely distributed in soil and water. NTM/Mycobacterium tuberculosis complex (MTBC) mixes may yield positive AFB smears falsely attributed to tuberculosis (TB) and false-resistance profiles for TB due to contaminated diagnostic samples. This as well as isolation of NTM may pose diagnostic and management problems. Texas Center for Infectious Disease (TCID) is a hospital for patients with confirmed TB. After a cluster of isolates of Mycobacterium gordonae was identified, a quality assurance review found inadequate protocols which included eating and drinking prior to collection. Changes made to the sputum collection protocol included reeducation of respiratory therapists and a sterile saline rinse intervention prior to sputum collection. Methods All sputa collected for AFB culture from diagnosed TB patients at TCID from January 1st, 2014 to December 31st, 2014 prior to the intervention and from August 1st, 2016 to January 31st, 2017, the 6 months following the quality assurance intervention were included. Sputum samples were processed at the Texas Department of State and Health Services (DSHS) Laboratory. Results A total of 1,853 sputum samples were processed; 1,288 from 2014 and 565 following the intervention. NTM decreased from 56 (4.3%) to 7 (1.2%) after the quality assurance intervention was instituted for a NTM decrease of 75.0%. M. gordonae decreased by 78.6%. No patients had evidence of NTM disease. Conclusion A breach in sputum collection protocols at TCID accounted for the increase in NTM isolation in 2014, half of which were M. gordonae. The reeducation of respiratory therapy staff and initiation of sterile saline rinse prior to sputum collection resulted in a significant reduction in the overall NTM rate. M. gordonae was isolated only three times following the intervention. At TCID, a location where tap water and bottled water contains NTM, drinking these prior to sputum collection possibly contributed to the cluster for NTM, especially M. gordonae. We recommend rinsing the mouth with sterile saline or water prior to sputum collection to decrease isolation of rarely pathogenic NTM. Disclosures All authors: No reported disclosures.
Wang, Jay Ching Chieh; Wang, Aikun; Gao, Jiangyuan; Cao, Sijia; Samad, Idris; Zhang, Dean; Ritland, Carol; Cui, Jing Z.
2012-01-01
Background Recent genomic technologies have propelled our understanding of the mechanisms underlying complex eye diseases such as age-related macular degeneration (AMD). Genotyping postmortem eye tissues for known single nucleotide polymorphisms (SNPs) associated with AMD may prove valuable, especially when combined with information obtained through other methods such as immunohistochemistry, western blot, enzyme-linked immunosorbent assay (ELISA), and proteomics. Initially intending to genotype postmortem eye tissues for AMD-related SNPs, our group became interested in isolating and comparing the quality of DNA from the iris and retina of postmortem donor eyes. Since there is no previously published protocol in the literature on this topic, we present a protocol suitable for isolating high-quality DNA from postmortem eye tissues for genomic studies. Methods DNA from 33 retinal samples and 35 iris samples was extracted using the phenol-chloroform-isoamyl method from postmortem donor eye tissues. The quantity of DNA was measured with a spectrophotometer while the quality was checked using gel electrophoresis. The DNA samples were then amplified with PCR for the complement factor H (CFH) gene. The purified amplified products were then genotyped for the SNPs in the CFH gene. Results Regarding concentration, the retina yielded 936 ng/μl of DNA, while the iris yielded 78 ng/μl of DNA. Retinal DNA was also purer than iris DNA (260/280=1.78 vs. 1.46, respectively), and produced superior PCR results. Retinal tissue yielded significantly more DNA than the iris tissue per mg of sample (21.7 ng/μl/mg vs. 7.42 ng/μl/mg). Retinal DNA can be readily amplified with PCR, while iris DNA can also be amplified by adding bovine serum albumin. Overall, retinal tissues yielded DNA of superior quality, quantity, and suitability for genotyping and genomic studies. Conclusions The protocol presented here provides a clear and reliable method for isolating total DNA from postmortem eye tissues. Retinal tissue provides DNA of excellent quantity and quality for genotyping and downstream genomic studies. However, DNA isolated from iris tissues, and treated with bovine serum albumin, may also be a valuable source of DNA for genotyping and genomic studies. PMID:23288996
NASA Astrophysics Data System (ADS)
Zhao, Yijia; Zhang, Yichen; Xu, Bingjie; Yu, Song; Guo, Hong
2018-04-01
The method of improving the performance of continuous-variable quantum key distribution protocols by postselection has been recently proposed and verified. In continuous-variable measurement-device-independent quantum key distribution (CV-MDI QKD) protocols, the measurement results are obtained from untrusted third party Charlie. There is still not an effective method of improving CV-MDI QKD by the postselection with untrusted measurement. We propose a method to improve the performance of coherent-state CV-MDI QKD protocol by virtual photon subtraction via non-Gaussian postselection. The non-Gaussian postselection of transmitted data is equivalent to an ideal photon subtraction on the two-mode squeezed vacuum state, which is favorable to enhance the performance of CV-MDI QKD. In CV-MDI QKD protocol with non-Gaussian postselection, two users select their own data independently. We demonstrate that the optimal performance of the renovated CV-MDI QKD protocol is obtained with the transmitted data only selected by Alice. By setting appropriate parameters of the virtual photon subtraction, the secret key rate and tolerable excess noise are both improved at long transmission distance. The method provides an effective optimization scheme for the application of CV-MDI QKD protocols.
2010-01-01
Research in plant molecular biology involves DNA purification on a daily basis. Although different commercial kits enable convenient extraction of high-quality DNA from E. coli cells, PCR and agarose gel samples as well as plant tissues, each kit is designed for a particular type of DNA extraction work, and the cost of purchasing these kits over a long run can be considerable. Furthermore, a simple method for the isolation of binary plasmid from Agrobacterium tumefaciens cells with satisfactory yield is lacking. Here we describe an easy protocol using homemade silicon dioxide matrix and seven simple solutions for DNA extraction from E. coli and A. tumefaciens cells, PCR and restriction digests, agarose gel slices, and plant tissues. Compared with the commercial kits, this protocol allows rapid DNA purification from diverse sources with comparable yield and purity at negligible cost. Following this protocol, we have demonstrated: (1) DNA fragments as small as a MYC-epitope tag coding sequence can be successfully recovered from an agarose gel slice; (2) Miniprep DNA from E. coli can be eluted with as little as 5 μl water, leading to high DNA concentrations (>1 μg/μl) for efficient biolistic bombardment of Arabidopsis seedlings, polyethylene glycol (PEG)-mediated Arabidopsis protoplast transfection and maize protoplast electroporation; (3) Binary plasmid DNA prepared from A. tumefaciens is suitable for verification by restriction analysis without the need for large scale propagation; (4) High-quality genomic DNA is readily isolated from several plant species including Arabidopsis, tobacco and maize. Thus, the silicon dioxide matrix-based DNA purification protocol offers an easy, efficient and economical way to extract DNA for various purposes in plant research. PMID:20180960
Delta Alert: Expanding Gerotrauma Criteria to Improve Patient Outcomes: A 2-Year Study.
Wiles, Lynn L; Day, Mark D
Because of their decreased physical reserve and increased risk of complications, the geriatric trauma patient (GTP) population warrants heightened awareness by clinical staff. The purpose of this study is to determine whether the institution of a third-tier trauma protocol results in a change in GTP outcomes, complications, and mortality rates. Researchers conducted a retrospective review of 2 years of data from the trauma registry, hospital quality improvement audits, and patient charts to examine what, if any, patient outcomes were impacted by the institution of the expanded GTP protocol. Sample homogeneity was determined. Emergency department (ED) length of stay and time to the operating room decreased in the protocol cohort. The rate of complications decreased from 16.4% preprotocol to 1.6% postprotocol. Discharge to home rates in the GTP population improved from 31% preprotocol to nearly 77% postimplementation of the protocol. The expanded GTP protocol front loads evaluation and resuscitation to be consistent with ED trauma protocols already in place. By fast-tracking radiology and laboratory testing, patients injuries are identified and the appropriate consultations are initiated. Appropriate inpatient nursing unit placement is identified or treatment and discharge from the ED are expedited. The expanded GTP protocol provided early and comprehensive evaluation and interventions for GTPs who fall outside of traditional trauma alert criteria. Patients spend less time in the ED and the hospital. Patients had decreased length of stay in the ED, less complications, and return to home rates showed significant improvement after the protocol was implemented.
A socialization intervention in remote health coaching for older adults in the home.
Jimison, Holly B; Klein, Krystal A; Marcoe, Jennifer L
2013-01-01
Previous studies have shown that social ties enhance both physical and mental health, and that social isolation has been linked to increased cognitive decline. As part of our cognitive training platform, we created a socialization intervention to address these issues. The intervention is designed to improve social contact time of older adults with remote family members and friends using a variety of technologies, including Web cameras, Skype software, email and phone. We used usability testing, surveys, interviews and system usage monitoring to develop design guidance for socialization protocols that were appropriate for older adults living independently in their homes. Our early results with this intervention show increased number of social contacts, total communication time (we measure email, phone, and Skype usage) and significant participant satisfaction with the intervention.
Carpenter, Christopher R.; Platts-Mills, Timothy F.
2013-01-01
Alternative management methods are essential to ensure high quality and efficient emergency care for the growing number of geriatric adults worldwide. Protocols for case-finding and rapid diagnosis to support early condition-specific treatment for older adults with acute severe illness and injury are needed. Improved emergency department care for older adults will require providers to look beyond the diagnosis to address the influence of other factors on the patient's health: isolation and depression; finances and transportation; and chronic medical conditions and polypharmacy. This review article describes recent and ongoing efforts to enhance the quality of emergency care for older adults using alternative management approaches spanning the spectrum from prehospital care, through the emergency department, and into evolving inpatient or outpatient processes of care. PMID:23177599
Microscale Laminar Vortices for High-Purity Extraction and Release of Circulating Tumor Cells.
Hur, Soojung Claire; Che, James; Di Carlo, Dino
2017-01-01
Circulating tumor cells (CTCs) are disseminated tumor cells that reflect the tumors of origin and can provide a liquid biopsy that would potentially enable noninvasive tumor profiling, treatment monitoring, and identification of targeted treatments. Accurate and rapid purification of CTCs holds great potential to improve cancer care but the task remains technically challenging. Microfluidic isolation of CTCs within microscale vortices enables high-throughput and size-based purification of rare CTCs from bodily fluids. Collected cells are highly pure, viable, and easily accessible, allowing seamless integration with various downstream applications. Here, we describe how to fabricate the High-Throughput Vortex Chip (Vortex-HT) and to process diluted whole blood for CTC collection. Lastly, immunostaining and imaging protocols for CTC classification and corresponding CTC image galleries are reported.
NASA Astrophysics Data System (ADS)
Isaad, Jalal; El Achari, Ahmida
2018-02-01
Novel family of azoic dyes pyrazolone based were prepared by an efficient and rapid methodology through diazotization reaction of different pyrazolone amine derivatives, in the presence of acidic ionic liquid supported on silica-coated magnetite nanoparticles as acidic catalyst at room temperature and under solvent-free conditions. The attractive advantages of the present process include short reaction times, milder and cleaner conditions, higher purity and yields, easy isolation of products, easier work-up procedure and lower generation of waste or pollution. This catalyst was easily separated by an external magnet and the recovered catalyst was reused several times without any significant loss of activity. Therefore, this method provides improved protocol over the existing methods.
A Socialization Intervention in Remote Health Coaching for Older Adults in the Home*
Jimison, Holly B.; Klein, Krystal A.; Marcoe, Jennifer L.
2014-01-01
Previous studies have shown that social ties enhance both physical and mental health, and that social isolation has been linked to increased cognitive decline. As part of our cognitive training platform, we created a socialization intervention to address these issues. The intervention is designed to improve social contact time of older adults with remote family members and friends using a variety of technologies, including Web cameras, Skype software, email and phone. We used usability testing, surveys, interviews and system usage monitoring to develop design guidance for socialization protocols that were appropriate for older adults living independently in their homes. Our early results with this intervention show increased number of social contacts, total communication time (we measure email, phone, and Skype usage) and significant participant satisfaction with the intervention. PMID:24111362
Couderc, Carine; Nappez, Claude; Drancourt, Michel
2012-03-30
It is recommended that harmful Biosafety Level 3 (BSL-3) bacteria be inactivated prior to identification by mass spectrometry, yet optimal effects of inactivation protocol have not been defined. Here, we compare trifluoroacetic acid inactivation (protocol A) with ethanol inactivation (protocol B) of Yersinia organisms prior to identification by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The total number of peaks detected was 10.5 ± 1.7 for protocol A and 15.7 ± 4.2 for protocol B (ρ <0.001, ANOVA test). The signal-to-noise ratio for the m/z 6049 peak present in all of the tested Yersinia isolates was 9.7 ± 3.1 for protocol A and 18.1 ± 4.6 for protocol B (ρ < 0.001). Compared with spectra in our local database containing 48 Yersinia spp., including 20 strains of Y. pestis, the identification score was 1.79 ± 0.2 for protocol A and 1.97 ± 0.19 for protocol B (ρ = 0.0024). Our observations indicate that for the identification of Yersinia organisms, ethanol inactivation yielded MALDI-TOF-MS spectra of significantly higher quality than spectra derived from trifluoroacetic acid inactivation. Combined with previously published data, our results permit the updating of protocols for inactivating BSL-3 bacteria. Copyright © 2012 John Wiley & Sons, Ltd.
Lamberton, Poppy H L; Faust, Christina L; Webster, Joanne P
2017-06-16
Mass drug administration of praziquantel is the World Health Organization's endorsed control strategy for schistosomiasis. A decade of annual treatments across sub-Saharan Africa has resulted in significant reductions of infection prevalence and intensity levels, although 'hotspots' remain. Repeated drug treatments place strong selective pressures on parasites, which may affect life-history traits that impact transmission dynamics. Understanding drug treatment responses and the evolution of such traits can help inform on how to minimise the risk of drug resistance developing, maximise sustainable control programme success, and improve diagnostic protocols. We performed a four-generation Schistosoma mansoni praziquantel selection experiment in mice and snails. We used three S. mansoni lines: a praziquantel-resistant isolate (R), a praziquantel-susceptible isolate (S), and a co-infected line (RS), under three treatment regimens: untreated, 25 mg/kg praziquantel, or 50 mg/kg praziquantel. Life-history traits, including parasite adult-worm establishment, survival, reproduction (fecundity), and associated morbidity, were recorded in mice across all four generations. Predictor variables were tested in a series of generalized linear mixed effects models to determine which factors had a significant influence on parasite life-history traits in definitive hosts under different selection regimes. Praziquantel pressure significantly reduced adult-worm burdens across all generations and isolates, including within R-lines. However, previous drug treatment resulted in an increase in adult-worm establishment with increasing generation from P1 to F3. The highest worm numbers were in the co-infected RS line. Praziquantel treatment decreased adult-worm burden, but had a larger negative impact on the mean daily number of miracidia, a proxy for fecundity, across all three parasite isolates. Our predicted cost of resistance was not supported by the traits we measured within the murine host. We did not find evidence for negative adult worm density-dependent effects on fecundity. In contrast, of the adult worms that survived treatment, even low doses of praziquantel significantly reduced adult-worm fecundity. Such reductions in worm fecundity post treatment suggest that egg - based measures of drug efficacy, such as Kato-Katz, may overestimate the short-term effect of praziquantel on adult - worm burdens. These findings have important implications for S. mansoni transmission control, diagnostic protocols, and the potential for undetected selection toward drug resistance.
Indication-Based Ordering: A New Paradigm for Glycemic Control in Hospitalized Inpatients
Lee, Joshua; Clay, Brian; Zelazny, Ziband; Maynard, Gregory
2008-01-01
Background Inpatient glycemic control is a constant challenge. Institutional insulin management protocols and structured order sets are commonly advocated but poorly studied. Effective and validated methods to integrate algorithmic protocol guidance into the insulin ordering process are needed. Methods We introduced a basic structured set of computerized insulin orders (Version 1), and later introduced a paper insulin management protocol, to assist users with the order set. Metrics were devised to assess the impact of the protocol on insulin use, glycemic control, and hypoglycemia using pharmacy data and point of care glucose tests. When incremental improvement was seen (as described in the results), Version 2 of the insulin orders was created to further streamline the process. Results The percentage of regimens containing basal insulin improved with Version 1. The percentage of patient days with hypoglycemia improved from 3.68% at baseline to 2.59% with Version 1 plus the paper insulin management protocol, representing a relative risk for hypoglycemic day of 0.70 [confidence interval (CI) 0.62, 0.80]. The relative risk of an uncontrolled (mean glucose over 180 mg/dl) patient stay was reduced to 0.84 (CI 0.77, 0.91) with Version 1 and was reduced further to 0.73 (CI 0.66, 0.81) with the paper protocol. Version 2 used clinician-entered patient parameters to guide protocol-based insulin ordering and simultaneously improved the flexibility and ease of ordering over Version 1. Conclusion Patient parameter and protocol-based clinical decision support, added to computerized provider order entry, has a track record of improving glycemic control indices. This justifies the incorporation of these algorithms into online order management. PMID:19885198
Qiu, Shi; Yang, Wen-Zhi; Shi, Xiao-Jian; Yao, Chang-Liang; Yang, Min; Liu, Xuan; Jiang, Bao-Hong; Wu, Wan-Ying; Guo, De-An
2015-09-17
Exploration of new natural compounds is of vital significance for drug discovery and development. The conventional approaches by systematic phytochemical isolation are low-efficiency and consume masses of organic solvent. This study presents an integrated strategy that combines offline comprehensive two-dimensional liquid chromatography, hybrid linear ion-trap/Orbitrap mass spectrometry, and NMR analysis (2D LC/LTQ-Orbitrap-MS/NMR), aimed to establish a green protocol for the efficient discovery of new natural molecules. A comprehensive chemical analysis of the total ginsenosides of stems and leaves of Panax ginseng (SLP), a cardiovascular disease medicine, was performed following this strategy. An offline 2D LC system was constructed with an orthogonality of 0.79 and a practical peak capacity of 11,000. The much greener UHPLC separation and LTQ-Orbitrap-MS detection by data-dependent high-energy C-trap dissociation (HCD)/dynamic exclusion were employed for separation and characterization of ginsenosides from thirteen fractionated SLP samples. Consequently, a total of 646 ginsenosides were characterized, and 427 have not been isolated from the genus of Panax L. The ginsenosides identified from SLP exhibited distinct sapogenin diversity and molecular isomerism. NMR analysis was finally employed to verify and offer complementary structural information to MS-oriented characterization. The established 2D LC/LTQ-Orbitrap-MS/NMR approach outperforms the conventional approaches in respect of significantly improved efficiency, much less use of drug materials and organic solvent. The integrated strategy enables a deep investigation on the therapeutic basis of an herbal medicine, and facilitates new compounds discovery in an efficient and environmentally friendly manner as well. Copyright © 2015 Elsevier B.V. All rights reserved.
Belo, Luís; Serrano, Isa; Cunha, Eva; Carneiro, Carla; Tavares, Luis; Miguel Carreira, L; Oliveira, Manuela
2018-03-14
Most of surgical site infections (SSI) are caused by commensal and pathogenic agents from the patient's microbiota, which may include antibiotic resistant strains. Pre-surgical asepsis of the skin is one of the preventive measures performed to reduce SSI incidence and also antibiotic resistance dissemination. However, in veterinary medicine there is no agreement on which biocide is the most effective. The aim of this study was to evaluate the effectiveness of two pre-surgical skin asepsis protocols in dogs. A total of 46 animals were randomly assigned for an asepsis protocol with an aqueous solution of 7.5% povidone-iodine or with an alcoholic solution of 2% chlorhexidine. For each dog, two skin swab samples were collected at pre-asepsis and post-asepsis, for bacterial quantification by conventional techniques and isolation of methicillin-resistant species. Most samples collected at the post-asepsis did not present bacterial growth, both for the animals subjected to the povidone-iodine (74%) or to the chlorhexidine (70%) protocols. In only 9% of the cases a significant bacterial logarithmic reduction was not observed, indicating possible resistance to these agents. Also, the logarithmic reduction of the bacterial quantification from pre- and post-asepsis time, was not statistically different for povidone-iodine (6.51 ± 1.94 log10) and chlorhexidine (6.46 ± 2.62 log10) protocol. From the 39% pre-asepsis swabs which showed bacterial growth in MRSA modified chromogenic agar medium, only one isolate was identified as Staphylococcus aureus and one as S. epidermidis. False positives were mainly other staphylococci species, as well as Enterobacteriaceae. Pre-surgical skin asepsis protocols with povidone-iodine or chlorhexidine showed similar efficacy in the elimination of methicillin resistant bacteria and preventing surgical site infections in dogs undergoing surgery.
Grass, Gregor; Ahrens, Bjoern; Schleenbecker, Uwe; Dobrzykowski, Linda; Wagner, Matthias; Krüger, Christian; Wölfel, Roman
2016-02-01
We describe a culture-based method suitable for isolating Bacillus anthracis and other live bacteria from heroin. This protocol was developed as a consequence of the bioforensic need to retrieve bacteria from batches of the drug associated with cases of injectional anthrax among heroin-consumers in Europe. This uncommon manifestation of infection with the notorious pathogen B. anthracis has resulted in 26 deaths between the years 2000 to 2013. Thus far, no life disease agent has been isolated from heroin during forensic investigations surrounding these incidences. Because of the conjectured very small number of disease-causing endospores in the contaminated drug it is likely that too few target sequences are available for molecular genetic analysis. Therefore, a direct culture-based approach was chosen here. Endospores of attenuated B. anthracis artificially spiked into heroin were successfully retrieved at 84-98% recovery rates using a wash solution consisting of 0.5% Tween 20 in water. Using this approach, 82 samples of un-cut heroin originating from the German Federal Criminal Police Office's heroin analysis program seized during the period between 2000 and 2014 were tested and found to be surprisingly poor in retrievable bacteria. Notably, while no B. anthracis was isolated from the drug batches, other bacteria were successfully cultured. The resulting methodical protocol is therefore suitable for analyzing un-cut heroin which can be anticipated to comprise the original microbiota from the drug's original source without interference from contaminations introduced by cutting. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Broth versus solid agar culture of swab samples of cadaveric allograft musculoskeletal tissue.
Varettas, Kerry
2013-12-01
As part of the donor assessment protocol, bioburden assessment must be performed on allograft musculoskeletal tissue samples collected at the time of tissue retrieval. Swab samples of musculoskeletal tissue allografts from cadaveric donors are received at the microbiology department of the South Eastern Area Laboratory Services (Australia) to determine the presence of bacteria and fungi. This study will review the isolation rate of organisms from solid agar and broth culture of swab samples of cadaveric allograft musculoskeletal tissue over a 6-year period, 2006-2011. Swabs were inoculated onto horse blood agar (anaerobic, 35 °C) and chocolate agar (CO2, 35 °C) and then placed into a cooked meat broth (aerobic, 35 °C). A total of 1,912 swabs from 389 donors were received during the study period. 557 (29.1 %) swabs were culture positive with the isolation of 713 organisms, 249 (34.9 %) from solid agar culture and an additional 464 (65.1 %) from broth culture only. This study has shown that the broth culture of cadaveric allograft musculoskeletal swab samples recovered a greater amount of organisms than solid agar culture. Isolates such as Clostridium species and Staphylococcus aureus would not have been isolated from solid agar culture alone. Broth culture is an essential part of the bioburden assessment protocol of swab samples of cadaveric allograft musculoskeletal tissue in this laboratory.
Improving patient care in cardiac surgery using Toyota production system based methodology.
Culig, Michael H; Kunkle, Richard F; Frndak, Diane C; Grunden, Naida; Maher, Thomas D; Magovern, George J
2011-02-01
A new cardiac surgery program was developed in a community hospital setting using the operational excellence (OE) method, which is based on the principles of the Toyota production system. The initial results of the first 409 heart operations, performed over the 28 months between March 1, 2008, and June 30, 2010, are presented. Operational excellence methodology was taught to the cardiac surgery team. Coaching started 2 months before the opening of the program and continued for 24 months. Of the 409 cases presented, 253 were isolated coronary artery bypass graft operations. One operative death occurred. According to the database maintained by The Society of Thoracic Surgeons, the risk-adjusted operative mortality rate was 61% lower than the regional rate. Likewise, the risk-adjusted rate of major complications was 57% lower than The Society of Thoracic Surgeons regional rate. Daily solution to determine cause was attempted on 923 distinct perioperative problems by all team members. Using the cost of complications as described by Speir and coworkers, avoiding predicted complications resulted in a savings of at least $884,900 as compared with the regional average. By the systematic use of a real time, highly formatted problem-solving methodology, processes of care improved daily. Using carefully disciplined teamwork, reliable implementation of evidence-based protocols was realized by empowering the front line to make improvements. Low rates of complications were observed, and a cost savings of $3,497 per each case of isolated coronary artery bypass graft was realized. Copyright © 2011 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
Microbial production of four biodegradable siderophores under submerged fermentation.
Fazary, Ahmed E; Al-Shihri, Ayed S; Alfaifi, Mohammad Y; Saleh, Kamel A; Alshehri, Mohammed A; Elbehairi, Serag Eldin I; Ju, Yi-Hsu
2016-07-01
Four siderophore analogues were isolated and purified from Escherichia coli, Bacillus spp. ST13, and Streptomyces pilosus microorganisms under some specific submerged fermentation conditions. In order to evaluate the highest production of this siderophore analogues through the growth, a rapid spectrophotometric screening semi-quantitative method was used, in which interestingly the analogues were isolated in its own form not its iron chelate. After chromatographic separation, the chemical structures of the isolated and purified siderophores were illustrated using detailed spectroscopic techniques. The biodegradation studies were done on that four novel isolated and purified siderophores following OECD protocols. In addition, the bioactivities of these siderophores and their iron complexes were examined and evaluated. Copyright © 2016 Elsevier B.V. All rights reserved.
Isolation of Chromoplasts and Suborganellar Compartments from Tomato and Bell Pepper Fruit.
Barsan, Cristina; Kuntz, Marcel; Pech, Jean-Claude
2017-01-01
Tomato is a model for fruit development and ripening. The isolation of intact plastids from this organism is therefore important for metabolic and proteomic analyses. Pepper, a species from the same family, is also of interest since it allows isolation of intact chromoplasts in large amounts. Here, we provide a detailed protocol for the isolation of tomato plastids at three fruit developmental stages, namely, nascent chromoplasts from the mature green stage, chromoplasts from an intermediate stage, and fully differentiated red chromoplasts. The method relies on sucrose density gradient centrifugations. It yields high purity organelles suitable for proteome analyses. Enzymatic and microscopy assays are summarized to assess purity and intactness. A method is also described for subfractionation of pepper chromoplast lipoprotein structures.
Genetic characterization of measles viruses isolated in Turkey during 2000 and 2001
Korukluoglu, Gulay; Liffick, Stephanie; Guris, Dalya; Kobune, Fumio; Rota, Paul A; Bellini, William J; Ceylan, Ali; Ertem, Meliksah
2005-01-01
Background Molecular epidemiologic studies have made significant contributions to measles surveillance activities by helping to identify source and transmission pathways of the virus. This report describes the genetic characterization of wild-type measles viruses isolated in Turkey in 2000 and 2001. Results Wild-type measles viruses were isolated from 24 cases from five provinces in Turkey during 2001. The viruses were analyzed using the standard genotyping protocols. All isolates were classified as genotype D6, the same genotype that was identified in Turkey in previous outbreaks during 1998. Conclusion Turkey has begun implementation of a national program to eliminate measles by 2010. Therefore, this baseline genotype data will provide a means to monitor the success of the elimination program. PMID:16029506
Culturing primary mouse pancreatic ductal cells.
Reichert, Maximilian; Rhim, Andrew D; Rustgi, Anil K
2015-06-01
The most common subtype of pancreatic cancer is pancreatic ductal adenocarcinoma (PDAC). PDAC resembles ductal cells morphologically. To study pancreatic ductal cell (PDC) and pancreatic intraepithelial neoplasia (PanIN)/PDAC biology, it is essential to have reliable in vitro culture conditions. Here we describe a methodology to isolate, culture, and passage PDCs and duct-like cells from the mouse pancreas. It can be used to isolate cells from genetically engineered mouse models (GEMMs), providing a valuable tool to study disease models in vitro to complement in vivo findings. The culture conditions allow epithelial cells to outgrow fibroblast and other "contaminating" cell types within a few passages. However, the resulting cultures, although mostly epithelial, are not completely devoid of fibroblasts. Regardless, this protocol provides guidelines for a robust in vitro culture system to isolate, maintain, and expand primary pancreatic ductal epithelial cells. It can be applied to virtually all GEMMs of pancreatic disease and other diseases and cancers that arise from ductal structures. Because most carcinomas resemble ductal structures, this protocol has utility in the study of other cancers in addition to PDAC, such as breast and prostate cancers. © 2015 Cold Spring Harbor Laboratory Press.
Optimization of wireless sensor networks based on chicken swarm optimization algorithm
NASA Astrophysics Data System (ADS)
Wang, Qingxi; Zhu, Lihua
2017-05-01
In order to reduce the energy consumption of wireless sensor network and improve the survival time of network, the clustering routing protocol of wireless sensor networks based on chicken swarm optimization algorithm was proposed. On the basis of LEACH agreement, it was improved and perfected that the points on the cluster and the selection of cluster head using the chicken group optimization algorithm, and update the location of chicken which fall into the local optimum by Levy flight, enhance population diversity, ensure the global search capability of the algorithm. The new protocol avoided the die of partial node of intensive using by making balanced use of the network nodes, improved the survival time of wireless sensor network. The simulation experiments proved that the protocol is better than LEACH protocol on energy consumption, also is better than that of clustering routing protocol based on particle swarm optimization algorithm.
An Accurate Link Correlation Estimator for Improving Wireless Protocol Performance
Zhao, Zhiwei; Xu, Xianghua; Dong, Wei; Bu, Jiajun
2015-01-01
Wireless link correlation has shown significant impact on the performance of various sensor network protocols. Many works have been devoted to exploiting link correlation for protocol improvements. However, the effectiveness of these designs heavily relies on the accuracy of link correlation measurement. In this paper, we investigate state-of-the-art link correlation measurement and analyze the limitations of existing works. We then propose a novel lightweight and accurate link correlation estimation (LACE) approach based on the reasoning of link correlation formation. LACE combines both long-term and short-term link behaviors for link correlation estimation. We implement LACE as a stand-alone interface in TinyOS and incorporate it into both routing and flooding protocols. Simulation and testbed results show that LACE: (1) achieves more accurate and lightweight link correlation measurements than the state-of-the-art work; and (2) greatly improves the performance of protocols exploiting link correlation. PMID:25686314
Evaluation of a discharge education protocol for pediatric patients with gastrostomy tubes.
Schweitzer, Michelle; Aucoin, Julia; Docherty, Sharron L; Rice, Henry E; Thompson, Julie; Sullivan, Dori Taylor
2014-01-01
To evaluate the impact of a preprocedure education protocol for children who receive a gastrostomy tube (GT). A preintervention-postintervention design, using surveys and comparison between preprotocol and postprotocol cohorts, was used to evaluate the effect of implementation of a standardized GT education protocol with 26 subjects on caregiver, patient, and provider outcomes. The use of a preprocedure education protocol resulted in improved patient outcomes and increased caregiver knowledge and confidence and was considered a positive change by the providers. Often education is a forgotten part of a medical procedure, and the importance of education is typically only recognized after an adverse event occurs. Establishing a standardized evidence-based education protocol for GT care improves overall care and satisfaction. Use of a systematic and family-centered interdisciplinary approach markedly improves patient care. Copyright © 2014 National Association of Pediatric Nurse Practitioners. Published by Mosby, Inc. All rights reserved.
Quiroz, Karla A; Berríos, Miguel; Carrasco, Basilio; Retamales, Jorge B; Caligari, Peter D S; García-Gonzáles, Rolando
2017-06-02
Vegetative propagation of Fragaria sp. is traditionally carried out using stolons. This system of propagation, in addition to being slow, can spread plant diseases, particularly serious being viral. In vitro culture of meristems and the establishment of micropropagation protocols are important tools for solving these problems. In recent years, considerable effort has been made to develop in vitro propagation of the commercial strawberry in order to produce virus-free plants of high quality. These previous results can serve as the basis for developing in vitro-based propagation technologies in the less studied species Fragaria chiloensis. In this context, we studied the cultivation of meristems and establishment of a micropropagation protocol for F. chiloensis. The addition of polyvinylpyrrolidone (PVP) improved the meristem regeneration efficiency of F. chiloensis accessions. Similarly, the use of 6-benzylaminopurine (BAP) in the culture media increased the average rate of multiplication to 3-6 shoots per plant. In addition, the use of 6-benzylaminopurine (BAP), had low levels (near zero) of explant losses due to oxidation. However, plant height as well as number of leaves and roots were higher in media without growth regulators, with average values of 0.5 cm, 9 leaves and 4 roots per plant. For the first time in Chilean strawberry, meristem culture demonstrated to be an efficient tool for eliminating virus from infected plants, giving the possibility to produce disease free propagation material. Also, the addition of PVP into the basal MS medium improved the efficiency of plant recovery from isolated meristems. Farmers can now access to high quality plant material produced by biotech tools which will improve their technological practices.
The impact of major trauma network triage systems on patients with major burns.
Nizamoglu, Metin; O'Connor, Edmund Fitzgerald; Bache, Sarah; Theodorakopoulou, Evgenia; Sen, Sankhya; Sherren, Peter; Barnes, David; Dziewulski, Peter
2016-12-01
Trauma is a leading cause of death and disability worldwide. Patients presenting with severe trauma and burns benefit from specifically trained multidisciplinary teams. Regional trauma systems have shown improved outcomes for trauma patients. The aim of this study is to determine whether the development of major trauma systems have improved the management of patients with major burns. A retrospective study was performed over a four-year period reviewing all major burns in adults and children received at a regional burns centre in the UK before and after the implementation of the regional trauma systems and major trauma centres (MTC). Comparisons were drawn between three areas: (1) Patients presenting before the introduction of MTC and after the introduction of MTC. (2) Patients referred from MTC and non-MTC within the region, following the introduction of MTC. (3) Patients referred using the urban trauma protocol and the rural trauma protocol. Following the introduction of regional trauma systems and major trauma centres (MTC), isolated burn patients seen at our regional burns centre did not show any significant improvement in transfer times, admission resuscitation parameters, organ dysfunction or survival when referred from a MTC compared to a non-MTC emergency department. There was also no significant difference in survival when comparing referrals from all hospitals pre and post establishment of the major trauma network. No significant outcome benefit was demonstrated for burns patients referred via MTCs compared to non-MTCs. We suggest further research is needed to ascertain whether burns patients benefit from prolonged transfer times to a MTC compared to those seen at their local hospitals prior to transfer to a regional burns unit for further specialist care. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.
Dodd-McCue, Diane; Tartaglia, Alexander
2005-01-01
The Family Communication Coordinator (FCC) Protocol was implemented to provide early family intervention and to facilitate effective communications during potential organ donation cases. Previous studies found the Protocol associated with improved donor outcome measures and with reduced role stress for ICU nurses caring for potential donors. The present study examines the impact of the Protocol on the perceived role stress of hospital chaplains serving as FCCs. All hospital chaplains serving as FCCs at an academic teaching hospital were surveyed. Their perceptions of job dimensions, role stress, job satisfaction, and commitment were measured; interviews and secondary data supplemented the surveys. The findings demonstrate that the FCC Protocol is associated with improved role stress, specifically role ambiguity and role conflict, among hospital chaplains serving as FCCs. Additionally, the findings suggest that satisfaction with the Protocol may be associated with experience with the Protocol.
Sefuba, Maria; Walingo, Tom; Takawira, Fambirai
2015-09-18
This paper presents an Energy Efficient Medium Access Control (MAC) protocol for clustered wireless sensor networks that aims to improve energy efficiency and delay performance. The proposed protocol employs an adaptive cross-layer intra-cluster scheduling and an inter-cluster relay selection diversity. The scheduling is based on available data packets and remaining energy level of the source node (SN). This helps to minimize idle listening on nodes without data to transmit as well as reducing control packet overhead. The relay selection diversity is carried out between clusters, by the cluster head (CH), and the base station (BS). The diversity helps to improve network reliability and prolong the network lifetime. Relay selection is determined based on the communication distance, the remaining energy and the channel quality indicator (CQI) for the relay cluster head (RCH). An analytical framework for energy consumption and transmission delay for the proposed MAC protocol is presented in this work. The performance of the proposed MAC protocol is evaluated based on transmission delay, energy consumption, and network lifetime. The results obtained indicate that the proposed MAC protocol provides improved performance than traditional cluster based MAC protocols.
Sefuba, Maria; Walingo, Tom; Takawira, Fambirai
2015-01-01
This paper presents an Energy Efficient Medium Access Control (MAC) protocol for clustered wireless sensor networks that aims to improve energy efficiency and delay performance. The proposed protocol employs an adaptive cross-layer intra-cluster scheduling and an inter-cluster relay selection diversity. The scheduling is based on available data packets and remaining energy level of the source node (SN). This helps to minimize idle listening on nodes without data to transmit as well as reducing control packet overhead. The relay selection diversity is carried out between clusters, by the cluster head (CH), and the base station (BS). The diversity helps to improve network reliability and prolong the network lifetime. Relay selection is determined based on the communication distance, the remaining energy and the channel quality indicator (CQI) for the relay cluster head (RCH). An analytical framework for energy consumption and transmission delay for the proposed MAC protocol is presented in this work. The performance of the proposed MAC protocol is evaluated based on transmission delay, energy consumption, and network lifetime. The results obtained indicate that the proposed MAC protocol provides improved performance than traditional cluster based MAC protocols. PMID:26393608
Molecular typing of Chinese Streptococcus pyogenes isolates.
You, Yuanhai; Wang, Haibin; Bi, Zhenwang; Walker, Mark; Peng, Xianhui; Hu, Bin; Zhou, Haijian; Song, Yanyan; Tao, Xiaoxia; Kou, Zengqiang; Meng, Fanliang; Zhang, Menghan; Bi, Zhenqiang; Luo, Fengji; Zhang, Jianzhong
2015-06-01
Streptococcus pyogenes causes human infections ranging from mild pharyngitis and impetigo to serious diseases including necrotizing fasciitis and streptococcal toxic shock syndrome. The objective of this study was to compare molecular emm typing and pulsed field gel electrophoresis (PFGE) with multiple-locus variable-number tandem-repeat analysis (MLVA) for genotyping of Chinese S. pyogenes isolates. Molecular emm typing and PFGE were performed using standard protocols. Seven variable number tandem repeat (VNTR) loci reported in a previous study were used to genotype 169 S. pyogenes geographically-diverse isolates from China isolated from a variety of disease syndromes. Multiple-locus variable-number tandem-repeat analysis provided greater discrimination between isolates when compared to emm typing and PFGE. Removal of a single VNTR locus (Spy2) reduced the sensitivity by only 0.7%, which suggests that Spy2 was not informative for the isolates screened. The results presented support the use of MLVA as a powerful epidemiological tool for genotyping S. pyogenes clinical isolates. Copyright © 2015 Elsevier Ltd. All rights reserved.
Sakaridis, Ioannis; Ganopoulos, Ioannis; Madesis, Panagiotis; Tsaftaris, Athanasios; Argiriou, Anagnostis
2014-01-02
An outbreak situation of human listeriosis requires a fast and accurate protocol for typing Listeria monocytogenes . Existing techniques are either characterized by low discriminatory power or are laborious and require several days to give a final result. Polymerase chain reaction (PCR) coupled with high resolution melting (HRM) analysis was investigated in this study as an alternative tool for a rapid and precise genotyping of L. monocytogenes isolates. Fifty-five isolates of L. monocytogenes isolated from poultry carcasses and the environment of four slaughterhouses were typed by HRM analysis using two specific markers, internalin B and ssrA genes. The analysis of genotype confidence percentage of L. monocytogenes isolates produced by HRM analysis generated dendrograms with two major groups and several subgroups. Furthermore, the analysis of the HRM curves revealed that all L. monocytogenes isolates could easily be distinguished. In conclusion, HRM was proven to be a fast and powerful tool for genotyping isolates of L. monocytogenes .
de Freitas, Roseli Santos; Kamikawa, Camila Mika; Vicentini, Adriana Pardini
Current methods for the production of Histoplasma capsulatum antigens are problematic in terms of standardization, specificity, stability, repeatability and reproducibility. In this study, we sought to optimize the methodology for producing H. capsulatum antigens, and to evaluate its applicability. Antigenic preparations obtained from 12 H. capsulatum isolates were evaluated by double immunodiffusion and immunoblotting assays against homologous and heterologous sera. The evaluated and optimized protocol allowed a more stable production, as well as repeatable, reproducible, with shorter culture time and less costly. By double immunodiffusion and immunoblotting assays, the best pattern of reactivity was observed for antigens obtained with 33 days of culture from the isolates 200 and 406 against the M antigen and for the isolate 200 with 15 days against H antigen. The SDS-PAGE presented antigenic components of molecular masses between 17 and 119kDa. The immunoblotting sensitivity was 95.5% and 100% with histoplasmosis sera from ill patients and sera from H. capsulatum infected but otherwise healthy patients, respectively, to the antigen derived from isolates 200 and 406. We suggest the employment of the antigen from isolate 200, with 15 or 30 days of culture, in the double immunodiffusion and immunoblotting assays due to its good ability to discriminate both sera from patients with histoplasmosis illness and histoplasmosis infection, in addition to its high specificity against heterologous sera. Copyright © 2017 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.
Optimized Methods for the Isolation of Arabidopsis Female Central Cells and Their Nuclei
Park, Kyunghyuk; Frost, Jennifer M.; Adair, Adam James; Kim, Dong Min; Yun, Hyein; Brooks, Janie S.; Fischer, Robert L.; Choi, Yeonhee
2016-01-01
The Arabidopsis female gametophyte contains seven cells with eight haploid nuclei buried within layers of sporophytic tissue. Following double fertilization, the egg and central cells of the gametophyte develop into the embryo and endosperm of the seed, respectively. The epigenetic status of the central cell has long presented an enigma due both to its inaccessibility, and the fascinating epigenome of the endosperm, thought to have been inherited from the central cell following activity of the DEMETER demethylase enzyme, prior to fertilization. Here, we present for the first time, a method to isolate pure populations of Arabidopsis central cell nuclei. Utilizing a protocol designed to isolate leaf mesophyll protoplasts, we systematically optimized each step in order to efficiently separate central cells from the female gametophyte. We use initial manual pistil dissection followed by the derivation of central cell protoplasts, during which process the central cell emerges from the micropylar pole of the embryo sac. Then, we use a modified version of the Isolation of Nuclei TAgged in specific Cell Types (INTACT) protocol to purify central cell nuclei, resulting in a purity of 75–90% and a yield sufficient to undertake downstream molecular analyses. We find that the process is highly dependent on the health of the original plant tissue used, and the efficiency of protoplasting solution infiltration into the gametophyte. By isolating pure central cell populations, we have enabled elucidation of the physiology of this rare cell type, which in the future will provide novel insights into Arabidopsis reproduction. PMID:27788573
Isolation of intact sub-dermal secretory cavities from Eucalyptus
2010-01-01
Background The biosynthesis of plant natural products in sub-dermal secretory cavities is poorly understood at the molecular level, largely due to the difficulty of physically isolating these structures for study. Our aim was to develop a protocol for isolating live and intact sub-dermal secretory cavities, and to do this, we used leaves from three species of Eucalyptus with cavities that are relatively large and rich in essential oils. Results Leaves were digested using a variety of commercially available enzymes. A pectinase from Aspergillus niger was found to allow isolation of intact cavities after a relatively short incubation (12 h), with no visible artifacts from digestion and no loss of cellular integrity or cavity contents. Several measurements indicated the potential of the isolated cavities for further functional studies. First, the cavities were found to consume oxygen at a rate that is comparable to that estimated from leaf respiratory rates. Second, mRNA was extracted from cavities, and it was used to amplify a cDNA fragment with high similarity to that of a monoterpene synthase. Third, the contents of the cavity lumen were extracted, showing an unexpectedly low abundance of volatile essential oils and a sizeable amount of non-volatile material, which is contrary to the widely accepted role of secretory cavities as predominantly essential oil repositories. Conclusions The protocol described herein is likely to be adaptable to a range of Eucalyptus species with sub-dermal secretory cavities, and should find wide application in studies of the developmental and functional biology of these structures, and the biosynthesis of the plant natural products they contain. PMID:20807444
Selective Osmotic Shock for Islet Isolation in the Cadaveric Canine Pancreas.
Thompson, Elizabeth M; Sollinger, Jennifer L; Opara, Emmanuel C; Adin, Christopher A
2018-03-01
Currently, islet isolation is performed using harsh collagenases that cause nonspecific injury to both islets and exocrine tissue, negatively affecting the outcome of cell transplantation. We evaluated a novel islet isolation protocol utilizing high concentrations of glucose to cause selective osmotic shock (SOS). Islets have a membrane glucose transporter that allows adaptation to changes in glucose concentrations while exocrine tissue can be selectively destroyed by these osmolar shifts. Canine pancreata were obtained within 15 min after euthanasia from animals ( n = 6) euthanized for reasons unrelated to this study. Each pancreas was divided into 4 segments that were randomized to receive 300 mOsm glucose for 20 min (group 1), 600 mOsm for 20 min (group 2), 300 mOsm for 40 min (group 3), or 600 mOsm for 40 min (group 4). Islet yield, purity, and viability were compared between groups. Mean ± standard error of the mean islet yield for groups 1 to 4 was 428 ± 159, 560 ± 257, 878 ± 443, and 990 ± 394 islet equivalents per gram, respectively. Purity ranged from 37% to 45% without the use of density gradient centrifugation and was not significantly different between groups. Islet cell viability was excellent overall (89%) and did not differ between treatment protocol. Islet function was best in groups treated with 300 mOsm of glucose (stimulation index [SI] = 3.3), suggesting that the lower concentration of glucose may be preferred for use in canine islet isolation. SOS provides a widely available means for researchers to isolate canine islets for use in islet transplantation or in studies of canine islet physiology.
Cevik, Ozge Selin; Sahin, Leyla; Tamer, Lulufer
2018-05-01
The type and duration of exposure to stress is an important influence on emotional and cognitive functions. Learning is the adaptive response of the central nervous system that occurs in hippocampus which affects from environmental factors like exercise. In this study, we investigated effects of long term treadmill exercise on learning and behavior on chronic social isolated rat. Male Wistar rats (n = 32) randomly assigned into four groups: control, exercised, social isolation, social isolation + exercise during postnatal days (PNDs) 21-34. Social isolation protocol was applied during 14 days by placing rat in a cage one by one. Rats were exercised during 5 days, days were chosen randomly for overall 4 weeks (20, 30, 50, 60 min respectively). Finally, learning performance was evaluated by Morris water maze (MWM). Anxiety behavior was evaluated by Open field and elevated plus maze test. At the end of learning and behavior tests, the rats were decapitated to collect blood samples via intracardiac puncture and corticosterone analysis was performed with ELISA method. Animal weights and water consumption did not change significantly but food intake differed among groups. Corticosterone level did not change between groups. The frequency of entering to the target quadrant increased in exercised rat significantly. However, there was no difference in learning and memory in rats. Treadmill exercise reduced anxiety behavior significantly. Taken together these findings may point out that, long term treadmill exercise did not change learning and memory but reduced anxiety level of rat without changing corticosterone level. Copyright © 2018 Elsevier Inc. All rights reserved.
Bustamante, Ana V; Lucchesi, Paula M A; Parma, Alberto E
2009-10-01
The aim of this work was to adapt described MLVA protocols to the molecular typing and characterization of VTEC O157:H7 isolates from Argentina. Nine VNTR loci were amplified by PCR showing diversity values from 0.49 to 0.73. Nine MLVA profiles were observed and the cluster analysis indicated both unrelated and closely related VTEC O157:H7 strains. In spite of the limited number of isolates studied, the panel of VNTR used made it possible to perform a first approach of the high genetic diversity of native strains of O157:H7 by MLVA.
Jopson, Laura; Newton, Julia L; Palmer, Jeremy; Floudas, Achilleas; Isaacs, John; Qian, Jessica; Wilkinson, Jennifer; Trenell, Mike; Blamire, Andrew; Howel, Denise; Jones, David E
2015-01-01
Introduction Primary biliary cirrhosis (PBC) is an autoimmune liver disease with approximately 50% of patients experiencing fatigue. This can be a particularly debilitating symptom, affecting quality of life and resulting in social isolation. Fatigue is highlighted by patients as a priority for research and patient support groups were involved in designing this trial. This is the first randomised controlled trial to investigate a treatment for fatigue in PBC. The trial protocol is innovative as it utilises novel magnetic resonance spectroscopy (MRS) techniques as an outcome measure. The protocol will be valuable to research groups planning clinical trials targeting fatigue in PBC and also transferrable to other conditions associated with fatigue. Methods and analysis RITPBC is a Medical Research Council (MRC) and National Institute for Health Research (NIHR) Efficacy and Mechanism Evaluation Programme (EME)-funded project. It is a phase II, single-centre, randomised controlled, double-blinded trial comparing rituximab with placebo in fatigued PBC patients. 78 patients with PBC and moderate to severe fatigue will be randomised to receive two infusions of rituximab or placebo. The study aims to assess whether rituximab improves fatigue in patients with PBC, the safety, and tolerability of rituximab in PBC and the sustainability of any beneficial actions. The primary outcome will be an improvement in fatigue domain score of the PBC-40, a disease-specific quality of life measure, evaluated at 12-week assessment. Secondary outcome measures include novel MRS techniques assessing muscle bioenergetic function, physical activity, anaerobic threshold and symptom, and quality of life measures. The trial started recruiting in October 2012 and recruitment is ongoing. Ethics and dissemination The trial has ethical approval from the NRES Committee North East, has Clinical Trial Authorisation from MHRA and local R&D approval. Trial results will be communicated to participants, presented at national and international meetings and published in peer-reviewed journals. Trial registration number ISRCTN03978701. PMID:26297361
DDN (Defense Data Network) Protocol Handbook. Volume 1. DoD Military Standard Protocols
1985-12-01
official Military Standard communication protocols in use on the DDN are included, as are several ARPANET (Advanced Research Projects Agency Network... research protocols which are currently in use, and some protocols currently undergoing review. Tutorial information and auxiliary documents are also...compatible with DoD needs, by researchers wishing to improve the protocols, and by impleroentors of local area networks (LANs) wishing their
Volpe, Bruce T.; Lynch, Daniel; Rykman-Berland, Avrielle; Ferraro, Mark; Galgano, Michael; Hogan, Neville; Krebs, Hermano I.
2016-01-01
Investigators have demonstrated that a variety of intensive movement training protocols for persistent upper limb paralysis in patients with chronic stroke (6 months or more after stroke) improve motor outcome. This randomized controlled study determined in patients with upper limb motor impairment after chronic stroke whether movement therapy delivered by a robot or by a therapist using an intensive training protocol was superior. Robotic training (n = 11) and an intensive movement protocol (n = 10) improved the impairment measures of motor outcome significantly and comparably; there were no significant changes in disability measures. Motor gains were maintained at the 3-month evaluation after training. These data contribute to the growing awareness that persistent impairments in those with chronic stroke may not reflect exhausted capacity for improvement. These new protocols, rendered by either therapist or robot, can be standardized, tested, and replicated, and potentially will contribute to rational activity-based programs. PMID:18184932
An Architecture for SCADA Network Forensics
NASA Astrophysics Data System (ADS)
Kilpatrick, Tim; Gonzalez, Jesus; Chandia, Rodrigo; Papa, Mauricio; Shenoi, Sujeet
Supervisory control and data acquisition (SCADA) systems are widely used in industrial control and automation. Modern SCADA protocols often employ TCP/IP to transport sensor data and control signals. Meanwhile, corporate IT infrastructures are interconnecting with previously isolated SCADA networks. The use of TCP/IP as a carrier protocol and the interconnection of IT and SCADA networks raise serious security issues. This paper describes an architecture for SCADA network forensics. In addition to supporting forensic investigations of SCADA network incidents, the architecture incorporates mechanisms for monitoring process behavior, analyzing trends and optimizing plant performance.
Murinda, S E; Nguyen, L T; Nam, H M; Almeida, R A; Headrick, S J; Oliver, S P
2004-01-01
Six visits were conducted to four dairy farms to collect swab, liquid, and solid dairy farm environmental samples (165 to 180/farm; 15 sample types). The objective of the study was to determine on-farm sources of Campylobacter jejuni, Salmonella spp., Listeria monocytogenes, and Shiga toxin-producing Escherichia coli (STEC), which might serve as reservoirs for transmission of pathogens. Samples were analyzed using mostly U.S. Food and Drug Administration's Bacteriological Analytical Manual protocols; however, Salmonella spp., L. monocytogenes and STEC were co-enriched in universal pre-enrichment broth. Campylobacter jejuni were enriched in Bolton broth containing Bolton broth supplement. Pathogens were isolated on agar media, typed biochemically, and confirmed using multiplex polymerase chain reaction protocols. Campylobacter jejuni, Salmonella spp., L. monocytogenes, Sorbitol-negative (SN)-STEC O157:H7, and sorbitol-positive (SP)-STEC, respectively, were isolated from 5.06%, 3.76%, 6.51%, 0.72%, and 17.3% of samples evaluated. Whereas other pathogens were isolated from all four farms, SN-STEC O157:H7 were isolated from only two farms. Diverse serotypes of SP-STEC including O157:H7, O26:H11, O111, and O103 were isolated. None of the five pathogen groups studied were isolated from bulk tank milk (BTM). Most pathogens (44.2%) were isolated directly from fecal samples. Bovine fecal samples, lagoon water, bedding, bird droppings, and rat intestinal contents constituted areas of major concern on dairy farms. Although in-line milk filters from two farms tested positive for Salmonella or L. monocytogenes, none of the pathogens were detected in the corresponding BTM samples. Good manure management practices, including control of feral animals, are critical in assuring dairy farm hygiene. Identification of on-farm pathogen reservoirs could aid with implementation of farm-specific pathogen reduction programs.
Crétel-Durand, Elodie; Nouguerède, Emilie; Le Caer, Hervé; Rousseau, Frédérique; Retornaz, Frédérique; Guillem, Olivier; Couderc, Anne-Laure; Greillier, Laurent; Norguet, Emmanuelle; Cécile, Maud; Boulahssass, Rabia; Le Caer, Francoise; Tournier, Sandrine; Butaud, Chantal; Guillet, Pierre; Nahon, Sophie; Poudens, Laure; Kirscher, Sylvie; Loubière, Sandrine; Diaz, Nadine; Dhorne, Jean; Auquier, Pascal; Baumstarck, Karine
2017-04-12
Cancer incidence and social isolation increase along with advanced age, and social isolation potentiates the relative risk of death by cancer. Once spotted, social isolation can be averted with the intervention of a multidisciplinary team. Techniques of automation and remote assistance have already demonstrated their positive impact on falls prevention and quality of life (QoL), though little is known about their impact on socially isolated elderly patients supported for cancer. The primary objective of the PREDOMOS study is to evaluate the impact of establishing a Program of Social intervention associated with techniques of Domotic and Remote assistance (PS-DR) on the improvement of QoL of elderly isolated patients, treated for locally advanced or metastatic cancer. The secondary objectives include treatment failure, tolerance, survival, and autonomy. This trial is a multicenter, prospective, randomized, placebo-controlled, open-label, two-parallel group study. The setting is 10 French oncogeriatric centers. Inclusion criteria are patients aged at least 70 years with a social isolation risk and a histological diagnosis of cancer, locally advanced or metastatic disease. The groups are (1) the control group, receiving usual care; (2) the experimental group, receiving usual care associating with monthly social assistance, domotic, and remote assistance. Participants are randomized in a 1:1 allocation ratio. Evaluation times involve inclusion (randomization) and follow-up (12 months). The primary endpoint is QoL at 3 months (via European Organization for Research and Treatment of Cancer (EORTC) QLQ C30); secondary endpoints are social isolation, time to treatment failure, toxicity, dose response-intensity, survival, autonomy, and QoL at 6 months. For the sample size, 320 individuals are required to obtain 90% power to detect a 10-point difference (standard deviation 25) in QoL score between the two groups (20% loss to follow-up patients expected). The randomized controlled design is the most appropriate design to demonstrate the efficacy of a new experimental strategy (Evidence-Based Medicine Working Group classification). National and international recommendations could be updated based on the findings of this study. ClinicalTrials.gov, NCT02829762 . Registered on 29 June 2016.
IRB Process Improvements: A Machine Learning Analysis.
Shoenbill, Kimberly; Song, Yiqiang; Cobb, Nichelle L; Drezner, Marc K; Mendonca, Eneida A
2017-06-01
Clinical research involving humans is critically important, but it is a lengthy and expensive process. Most studies require institutional review board (IRB) approval. Our objective is to identify predictors of delays or accelerations in the IRB review process and apply this knowledge to inform process change in an effort to improve IRB efficiency, transparency, consistency and communication. We analyzed timelines of protocol submissions to determine protocol or IRB characteristics associated with different processing times. Our evaluation included single variable analysis to identify significant predictors of IRB processing time and machine learning methods to predict processing times through the IRB review system. Based on initial identified predictors, changes to IRB workflow and staffing procedures were instituted and we repeated our analysis. Our analysis identified several predictors of delays in the IRB review process including type of IRB review to be conducted, whether a protocol falls under Veteran's Administration purview and specific staff in charge of a protocol's review. We have identified several predictors of delays in IRB protocol review processing times using statistical and machine learning methods. Application of this knowledge to process improvement efforts in two IRBs has led to increased efficiency in protocol review. The workflow and system enhancements that are being made support our four-part goal of improving IRB efficiency, consistency, transparency, and communication.
Purification of Lysosomes Using Supraparamagnetic Iron Oxide Nanoparticles (SPIONs).
Rofe, Adam P; Pryor, Paul R
2016-04-01
Lysosomes can be rapidly isolated from tissue culture cells using supraparamagnetic iron oxide particles (SPIONs). In this protocol, colloidal iron dextran (FeDex) particles, a type of SPION, are taken up by cultured mouse macrophage cells via the endocytic pathway. The SPIONs accumulate in lysosomes, the end point of the endocytic pathway, permitting the lysosomes to be isolated magnetically. The purified lysosomes are suitable for in vitro fusion assays or for proteomic analysis. © 2016 Cold Spring Harbor Laboratory Press.
Timpa, Joseph G; O'Meara, L Carlisle; Goldberg, Kellen G; Phillips, Jay P; Crawford, Jack H; Jackson, Kimberly W; Alten, Jeffrey A
2016-03-01
Perioperative transfusion of blood products is associated with increased morbidity and mortality after pediatric cardiac surgery. We report the results of a quality improvement project aimed at decreasing perioperative blood product administration and bleeding after pediatric cardiopulmonary bypass (CPB) surgery. A multidisciplinary team evaluated baseline data from 99 consecutive CPB patients, focusing on the variability in transfusion management and bleeding outcomes, to create a standardized bleeding and transfusion management protocol. A total of 62 subsequent patients were evaluated after implementation of the protocol: 17 with single pass hemoconcentrated (SPHC) blood transfusion and 45 with modified ultrafiltration (MUF). Implementation of the protocol with SPHC blood led to significant decrease in transfusion of every blood product in the cardiovascular operating room and first 6 hours in cardiovascular intensive care unit ([CVICU] p < .05). Addition of MUF to the protocol led to further decrease in transfusion of all blood products compared to preprotocol. Patients <2 months old had 49% decrease in total blood product administration: 155 mL/kg preprotocol, 117 mL/kg protocol plus SPHC, and 79 mL/kg protocol plus MUF (p < .01). There were significant decreases in postoperative bleeding in the first hour after CVICU admission: 6 mL/kg preprotocol, 3.8 mL/kg protocol plus SPHC, and 2 mL/kg protocol plusMUF (p = .02). There was also significantly decreased incidence of severe postoperative bleeding (>10 mL/kg) in the first CVICU hour for protocol plus MUF patients (p < .01). Implementation of a multidisciplinary bleeding and transfusion protocol significantly decreases perioperative blood product transfusion and improves some bleeding outcomes.
Selection of G1 Phase Yeast Cells for Synchronous Meiosis and Sporulation.
Stuart, David T
2017-01-01
Centrifugal elutriation is a procedure that allows the fractionation of cell populations based upon their size and shape. This allows cells in distinct cell cycle stages can be captured from an asynchronous population. The technique is particularly helpful when performing an experiment to monitor the progression of cells through the cell cycle or meiosis. Yeast sporulation like gametogenesis in other eukaryotes initiates from the G1 phase of the cell cycle. Conveniently, S. cerevisiae arrest in G1 phase when starved for nutrients and so withdrawal of nitrogen and glucose allows cells to abandon vegetative growth in G1 phase before initiating the sporulation program. This simple starvation protocol yields a partial synchronization that has been used extensively in studies of progression through meiosis and sporulation. By using centrifugal elutriation it is possible to isolate a homogeneous population of G1 phase cells and induce them to sporulate synchronously, which is beneficial for investigating progression through meiosis and sporulation. An additionally benefit of this protocol is that cell populations can be isolated based upon size and both large and small cell populations can be tested for progression through meiosis and sporulation. Here we present a protocol for purification of G1 phase diploid cells for examining synchronous progression through meiosis and sporulation.
Nohara, Kazunari; Chen, Zheng; Yoo, Seung-Hee
2017-07-06
Chromatin immunoprecipitation (ChIP) is a powerful method to determine protein binding to chromatin DNA. Fiber-rich skeletal muscle, however, has been a challenge for ChIP due to technical difficulty in isolation of high-quality nuclei with minimal contamination of myofibrils. Previous protocols have attempted to purify nuclei before cross-linking, which incurs the risk of altered DNA-protein interaction during the prolonged nuclei preparation process. In the current protocol, we first cross-linked the skeletal muscle tissue collected from mice, and the tissues were minced and sonicated. Since we found that ultracentrifugation was not able to separate nuclei from myofibrils using cross-linked muscle tissue, we devised a sequential filtration procedure to obtain high-quality nuclei devoid of significant myofibril contamination. We subsequently prepared chromatin by using an ultrasonicator, and ChIP assays with anti-BMAL1 antibody revealed robust circadian binding pattern of BMAL1 to target gene promoters. This filtration protocol constitutes an easily applicable method to isolate high-quality nuclei from cross-linked skeletal muscle tissue, allowing consistent sample processing for circadian and other time-sensitive studies. In combination with next-generation sequencing (NGS), our method can be deployed for various mechanistic and genomic studies focusing on skeletal muscle function.
Standard protocols for isolating, cryopreserving, and thawing rainbow trout hepatocytes are described, along with procedures for using fresh or cryopreserved hepatocytes to assess chemical metabolic stability in fish by means of a substrate depletion approach. Variations on thes...
Head CT: Image quality improvement with ASIR-V using a reduced radiation dose protocol for children.
Kim, Hyun Gi; Lee, Ho-Joon; Lee, Seung-Koo; Kim, Hyun Ji; Kim, Myung-Joon
2017-09-01
To investigate the quality of images reconstructed with adaptive statistical iterative reconstruction V (ASIR-V), using pediatric head CT protocols. A phantom was scanned at decreasing 20% mA intervals using our standard pediatric head CT protocols. Each study was then reconstructed at 10% ASIR-V intervals. After the phantom study, we reduced mA by 10% in the protocol for <3-year-old patients and applied 30% ASIR-V and by 30% in the protocol for 3- to 15-year-old patients and applied 40% ASIR-V. Increasing the percentage of ASIR-V resulted in lower noise and higher contrast-to-noise ratio (CNR) and preserved spatial resolution in the phantom study. Compared to a conventional-protocol, reduced-dose protocol with ASIR-V achieved 12.8% to 34.0% of dose reduction and showed images of lower noise (9.22 vs. 10.73, P = 0.043) and higher CNR in different levels (centrum semiovale, 2.14 vs. 1.52, P = 0.003; basal ganglia, 1.46 vs. 1.07, P = 0.001; and cerebellum, 2.18 vs. 1.33, P < 0.001). Qualitative analysis showed higher gray-white matter differentiation and sharpness and preserved overall diagnostic quality in the images with ASIR-V. Use of ASIR-V allowed a 12.8% to 34.0% dose reduction in each age group with potential to improve image quality. • It is possible to reduce radiation dose and improve image quality with ASIR-V. • We improved noise and CNR and decreased radiation dose. • Sharpness improved with ASIR-V. • Total radiation dose was decreased by 12.8% to 34.0%.
Comparison of Protein Extracts from Various Unicellular Green Sources.
Teuling, Emma; Wierenga, Peter A; Schrama, Johan W; Gruppen, Harry
2017-09-13
Photosynthetic unicellular organisms are considered as promising alternative protein sources. The aim of this study is to understand the extent to which these green sources differ with respect to their gross composition and how these differences affect the final protein isolate. Using mild isolation techniques, proteins were extracted and isolated from four different unicellular sources (Arthrospira (spirulina) maxima, Nannochloropsis gaditana, Tetraselmis impellucida, and Scenedesmus dimorphus). Despite differences in protein contents of the sources (27-62% w/w) and in protein extractability (17-74% w/w), final protein isolates were obtained that had similar protein contents (62-77% w/w) and protein yields (3-9% w/w). Protein solubility as a function of pH was different between the sources and in ionic strength dependency, especially at pH < 4.0. Overall, the characterization and extraction protocol used allows a relatively fast and well-described isolation of purified proteins from novel protein sources.
Umbilical cord fibroblasts: Could they be considered as mesenchymal stem cells?
Zeddou, Mustapha; Relic, Biserka; Malaise, Michel G
2014-01-01
In cell therapy protocols, many tissues were proposed as a source of mesenchymal stem cells (MSC) isolation. So far, bone marrow (BM) has been presented as the main source of MSC despite the invasive isolation procedure related to this source. During the last years, the umbilical cord (UC) matrix was cited in different studies as a reliable source from which long term ex vivo proliferating fibroblasts were isolated but with contradictory data about their immunophenotype, gene expression profile, and differentiation potential. Hence, an interesting question emerged: Are cells isolated from cord matrix (UC-MSC) different from other MSCs? In this review, we will summarize different studies that isolated and characterized UC-MSC. Considering BM-MSC as gold standard, we will discuss if UC-MSC fulfill different criteria that define MSC, and what remain to be done in this issue. PMID:25126385
2010-01-01
Background The staphylococci are one of the most common environmental isolates found in clean room facility. Consequently, isolation followed by comprehensive and accurate identification is an essential step in any environmental monitoring program. Findings We have used the API Staph identification kit (bioMérieux, France) which depends on the expression of metabolic activities and or morphological features to identify the Staphylococcus isolates. The API staphylococci showed low sensitivity in the identification of some species, so we performed molecular methods based on PCR based fingerprinting of glyceraldehyde-3-phosphate dehydrogenase encoding gene as useful taxonomic tool for examining Staphylococcus isolates. Conclusions Our results showed that PCR protocol used in this study which depends on genotypic features was relatively accurate, rapid, sensitive and superior in the identification of at least 7 species of Staphylococcus than API Staph which depends on phenotypic features. PMID:21047438
Sheraba, Norhan S; Yassin, Aymen S; Amin, Magdy A
2010-11-04
The staphylococci are one of the most common environmental isolates found in clean room facility. Consequently, isolation followed by comprehensive and accurate identification is an essential step in any environmental monitoring program. We have used the API Staph identification kit (bioMérieux, France) which depends on the expression of metabolic activities and or morphological features to identify the Staphylococcus isolates. The API staphylococci showed low sensitivity in the identification of some species, so we performed molecular methods based on PCR based fingerprinting of glyceraldehyde-3-phosphate dehydrogenase encoding gene as useful taxonomic tool for examining Staphylococcus isolates. Our results showed that PCR protocol used in this study which depends on genotypic features was relatively accurate, rapid, sensitive and superior in the identification of at least 7 species of Staphylococcus than API Staph which depends on phenotypic features.
Comparison of Protein Extracts from Various Unicellular Green Sources
2017-01-01
Photosynthetic unicellular organisms are considered as promising alternative protein sources. The aim of this study is to understand the extent to which these green sources differ with respect to their gross composition and how these differences affect the final protein isolate. Using mild isolation techniques, proteins were extracted and isolated from four different unicellular sources (Arthrospira (spirulina) maxima, Nannochloropsis gaditana, Tetraselmis impellucida, and Scenedesmus dimorphus). Despite differences in protein contents of the sources (27–62% w/w) and in protein extractability (17–74% w/w), final protein isolates were obtained that had similar protein contents (62–77% w/w) and protein yields (3–9% w/w). Protein solubility as a function of pH was different between the sources and in ionic strength dependency, especially at pH < 4.0. Overall, the characterization and extraction protocol used allows a relatively fast and well-described isolation of purified proteins from novel protein sources. PMID:28701042
Enhancement of Beaconless Location-Based Routing with Signal Strength Assistance for Ad-Hoc Networks
NASA Astrophysics Data System (ADS)
Chen, Guowei; Itoh, Kenichi; Sato, Takuro
Routing in Ad-hoc networks is unreliable due to the mobility of the nodes. Location-based routing protocols, unlike other protocols which rely on flooding, excel in network scalability. Furthermore, new location-based routing protocols, like, e. g. BLR [1], IGF [2], & CBF [3] have been proposed, with the feature of not requiring beacons in MAC-layer, which improve more in terms of scalability. Such beaconless routing protocols can work efficiently in dense network areas. However, these protocols' algorithms have no ability to avoid from routing into sparse areas. In this article, historical signal strength has been added as a factor into the BLR algorithm, which avoids routing into sparse area, and consequently improves the global routing efficiency.
NASA Astrophysics Data System (ADS)
Liu, Zhi-Hao; Chen, Han-Wu
2018-02-01
As we know, the information leakage problem should be avoided in a secure quantum communication protocol. Unfortunately, it is found that this problem does exist in the large payload bidirectional quantum secure direct communication (BQSDC) protocol (Ye Int. J. Quantum. Inf. 11(5), 1350051 2013) which is based on entanglement swapping between any two Greenberger-Horne-Zeilinger (GHZ) states. To be specific, one half of the information interchanged in this protocol is leaked out unconsciously without any active attack from an eavesdropper. Afterward, this BQSDC protocol is revised to the one without information leakage. It is shown that the improved BQSDC protocol is secure against the general individual attack and has some obvious features compared with the original one.
Kortz, Teresa Bleakly; Axelrod, David M; Chisti, Mohammod J; Kache, Saraswati
2017-01-01
Pediatric sepsis has a high mortality rate in limited resource settings. Sepsis protocols have been shown to be a cost-effective strategy to improve morbidity and mortality in a variety of populations and settings. At Dhaka Hospital in Bangladesh, mortality from pediatric sepsis in high-risk children previously approached 60%, which prompted the implementation of an evidenced-based protocol in 2010. The clinical effectiveness of this protocol had not been measured. We hypothesized that implementation of a pediatric sepsis protocol improved clinical outcomes, including reducing mortality and length of hospital stay. This was a retrospective cohort study of children 1-59 months old with a diagnosis of sepsis, severe sepsis or septic shock admitted to Dhaka Hospital from 10/25/2009-10/25/2011. The primary outcome was inpatient mortality pre- and post-protocol implementation. Secondary outcomes included fluid overload, heart failure, respiratory insufficiency, length of hospital stay, and protocol compliance, as measured by antibiotic and fluid bolus administration within 60 minutes of hospital presentation. 404 patients were identified by a key-word search of the electronic medical record; 328 patients with a primary diagnosis of sepsis, severe sepsis, or septic shock were included (143 pre- and185 post-protocol) in the analysis. Pre- and post-protocol mortality were similar and not statistically significant (32.17% vs. 34.59%, p = 0.72). The adjusted odds ratio (AOR) for post-protocol mortality was 1.55 (95% CI, 0.88-2.71). The odds for developing fluid overload were significantly higher post-protocol (AOR 3.45, 95% CI, 2.04-5.85), as were the odds of developing heart failure (AOR 4.52, 95% CI, 1.43-14.29) and having a longer median length of stay (AOR 1.81, 95% CI 1.10-2.96). There was no statistically significant difference in respiratory insufficiency (pre- 65.7% vs. post- 70.3%, p = 0.4) or antibiotic administration between the cohorts (pre- 16.08% vs. post- 12.43%, p = 0.42). Implementation of a pediatric sepsis protocol did not improve all-cause mortality or length of stay and may have been associated with increased fluid overload and heart failure during the study period in a large, non-governmental hospital in Bangladesh. Similar rates of early antibiotic administration may indicate poor protocol compliance. Though evidenced-based protocols are a potential cost-effective strategy to improve outcomes, future studies should focus on optimal implementation of context-relevant sepsis protocols in limited resource settings.
Hamprecht, Axel; Christ, Sara; Oestreicher, Tanja; Plum, Georg; Kempf, Volkhard A J; Göttig, Stephan
2014-04-01
The rapid and correct identification of pathogens is of paramount importance for the treatment of patients with invasive infections. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) can speed up the identification of bacteria and fungi and has quickly been embraced by medical microbiology laboratories worldwide. Different MALDI-TOF systems have been compared in studies focussing on identification rates of different pathogens. Another aspect that has not been systematically assessed is the performance in daily routine and handling, which is important especially for microbiology routine laboratories. We compared two widespread commercial systems, Microflex LT Biotyper (Bruker) and VitekMS (bioMérieux), for the identification of 210 relevant clinical yeasts under routine conditions, using a time-saving direct transfer protocol. We assessed the need for an additional extraction step, the threshold for species identification and the duration of measurements with the two systems. The tested yeasts included 34 Candida albicans isolates, 144 non-albicans Candida spp. and 32 yeasts of different genera. The results of the two MS systems were compared with that of biochemical identification and, in case of discrepancies, DNA sequencing of the internal transcribed spacer or the large subunit of ribosomal DNA. Both systems correctly identified 96.2 % of isolates [202/210, non-significant (n.s.)]. Misidentifications were observed for VitekMS only (n = 5, no major errors, n.s.). VitekMS was the slower system (19.8 vs. 8.0 min for 10 samples, p = 0.002) but had the advantage of a more effective direct transfer protocol with less need for an additional extraction step.
Evaluation of routine enteric pathogens in hospitalized patients: A Canadian perspective
Gough, Kevin; Alfa, Michelle; Harding, Godfrey
1996-01-01
Diarrhea is a frequently encountered problem in hospitalized patients. Since nosocomial spread of routine enteric pathogens such as Salmonella species, Shigella species, Campylobacter species and Escherichia coli O:157 H:7 seldom occurs, testing for these organisms in patients hospitalized for longer than three days has been questioned. The goal of this study was to determine the length of hospitalization preceding detection of routine enteric pathogens and Clostridium difficile cytotoxin, and to develop guidelines for enteric cultures from hospitalized patients. The enteric pathogens detected in 1991 were C difficile toxin B(+), 77%; Campylobacter species, 10%; Salmonella species, 9%; E coli O:157 H:7, 3%; and Shigella species, 1%. For 1992, these numbers were 86%, 9%, 3%, 2% and 0%, respectively. None of the routine enteric pathogens isolated in 1991 or 1992 was detected in patients after their second day of hospitalization. Routine cultures for enteric pathogens on hospitalized patients were eliminated in February 1993, and physician ordering practices were monitored. With the exception of one campylobacter isolate per year, all routine enteric pathogens isolated in 1993 and 1994 were detected by the second day of hospitalization. Compliance with the changed protocol was 76% measured over a four-month period in 1993 and 74% over the year 1994. Savings of $3,648.10 were associated with rejecting 191 ‘inappropriate’ specimens in 1994. It was concluded that routine enteric cultures are unnecessary for patients hospitalized more than two days, and that appreciable financial savings can be achieved if revised protocols for processing stool cultures are instituted. However, when enteric protocol changes are in place compliance must be evaluated to ensure appropriate utilization. PMID:22514438
Minimizing losses by variational counter-diabatic driving
NASA Astrophysics Data System (ADS)
Sels, Dries; Polkovnikov, Anatoli
Despite the time-reversal symmetry of the microscopic dynamics of isolated systems, losses are ubiquitous in any process that tries to manipulate them. Whether it's the heat produced in a car engine or the decoherence of a qubit, all losses arise from our lack of control on the microscopic degrees of freedom of the system. Counter-diabatic driving protocols were proposed as a means to do fast changes in the Hamiltonian without exciting transitions. Such driving in principle allows one to realize arbitrarily fast annealing protocols or implement fast dissipationless driving, circumventing standard adiabatic limitations requiring infinitesimally slow rates. These ideas were tested and used both experimentally and theoretically in small systems, but in larger chaotic systems it is known that exact counter-diabatic protocols do not exist. Here we will present a simple variational approach allowing one to find best physical counter-diabatic protocols. We will show that, while they do not get rid of all transitions, the variational protocols are able to significantly reduce the induced fluctuations in the system. D.S. acknowledges support by the FWO.
An improved authenticated key agreement protocol for telecare medicine information system.
Liu, Wenhao; Xie, Qi; Wang, Shengbao; Hu, Bin
2016-01-01
In telecare medicine information systems (TMIS), identity authentication of patients plays an important role and has been widely studied in the research field. Generally, it is realized by an authenticated key agreement protocol, and many such protocols were proposed in the literature. Recently, Zhang et al. pointed out that Islam et al.'s protocol suffers from the following security weaknesses: (1) Any legal but malicious patient can reveal other user's identity; (2) An attacker can launch off-line password guessing attack and the impersonation attack if the patient's identity is compromised. Zhang et al. also proposed an improved authenticated key agreement scheme with privacy protection for TMIS. However, in this paper, we point out that Zhang et al.'s scheme cannot resist off-line password guessing attack, and it fails to provide the revocation of lost/stolen smartcard. In order to overcome these weaknesses, we propose an improved protocol, the security and authentication of which can be proven using applied pi calculus based formal verification tool ProVerif.
Meek, Stephen; Sutherland, Linda; Burdon, Tom
2015-01-01
The rat is one of the most commonly used laboratory animals in biomedical research and the recent isolation of genuine pluripotent rat embryonic stem (ES) cell lines has provided new opportunities for applying contemporary genetic engineering techniques to the rat and enhancing the use of this rodent in scientific research. Technical refinements that improve the stability of the rat ES cell cultures will undoubtedly further strengthen and broaden the use of these stem cells in biomedical research. Here, we describe a relatively simple and robust protocol that supports the propagation of germ line competent rat ES cells, and outline how tuning stem cell signaling using small molecule inhibitors can be used to both stabilize self-renewal of rat ES cell cultures and aid evaluation of their differentiation potential in vitro.
Bertolde, F Z; Almeida, A-A F; Silva, F A C; Oliveira, T M; Pirovani, C P
2014-07-04
Theobroma cacao is a woody and recalcitrant plant with a very high level of interfering compounds. Standard protocols for protein extraction were proposed for various types of samples, but the presence of interfering compounds in many samples prevented the isolation of proteins suitable for two-dimensional gel electrophoresis (2-DE). An efficient method to extract root proteins for 2-DE was established to overcome these problems. The main features of this protocol are: i) precipitation with trichloroacetic acid/acetone overnight to prepare the acetone dry powder (ADP), ii) several additional steps of sonication in the ADP preparation and extractions with dense sodium dodecyl sulfate and phenol, and iii) adding two stages of phenol extractions. Proteins were extracted from roots using this new protocol (Method B) and a protocol described in the literature for T. cacao leaves and meristems (Method A). Using these methods, we obtained a protein yield of about 0.7 and 2.5 mg per 1.0 g lyophilized root, and a total of 60 and 400 spots could be separated, respectively. Through Method B, it was possible to isolate high-quality protein and a high yield of roots from T. cacao for high-quality 2-DE gels. To demonstrate the quality of the extracted proteins from roots of T. cacao using Method B, several protein spots were cut from the 2-DE gels, analyzed by tandem mass spectrometry, and identified. Method B was further tested on Citrus roots, with a protein yield of about 2.7 mg per 1.0 g lyophilized root and 800 detected spots.
Hailemariam, Zerihun; Ahmed, Jabbar Sabir; Clausen, Peter-Henning; Nijhof, Ard Menzo
2017-01-01
An essential step in the molecular detection of tick-borne pathogens (TBPs) in blood is the extraction of DNA. When cooled storage of blood under field conditions prior to DNA extraction in a dedicated laboratory is not possible, the storage of blood on filter paper forms a promising alternative. We evaluated six DNA extraction methods from blood spotted on FTA Classic ® cards (FTA cards), to determine the optimal protocol for the subsequent molecular detection of TBPs by PCR and the Reverse Line Blot hybridization assay (RLB). Ten-fold serial dilutions of bovine blood infected with Babesia bovis, Theileria mutans, Anaplasma marginale or Ehrlichia ruminantium were made by dilution with uninfected blood and spotted on FTA cards. Subsequently, DNA was extracted from FTA cards using six different DNA extraction protocols. DNA was also isolated from whole blood dilutions using a commercial kit. PCR/RLB results showed that washing of 3mm discs punched from FTA cards with FTA purification reagent followed by DNA extraction using Chelex ® resin was the most sensitive procedure. The detection limit could be improved when more discs were used as starting material for the DNA extraction, whereby the use of sixteen 3mm discs proved to be most practical. The presented best practice method for the extraction of DNA from blood spotted on FTA cards will facilitate epidemiological studies on TBPs. It may be particularly useful for field studies where a cold chain is absent. Copyright © 2016 Elsevier GmbH. All rights reserved.
Cryptanalysis and improvement of a quantum communication-based online shopping mechanism
NASA Astrophysics Data System (ADS)
Huang, Wei; Yang, Ying-Hui; Jia, Heng-Yue
2015-06-01
Recently, Chou et al. (Electron Commer Res 14:349-367, 2014) presented a novel controlled quantum secure direct communication protocol which can be used for online shopping. The authors claimed that their protocol was immune to the attacks from both external eavesdropper and internal betrayer. However, we find that this protocol is vulnerable to the attack from internal betrayer. In this paper, we analyze the security of this protocol to show that the controller in this protocol is able to eavesdrop the secret information of the sender (i.e., the customer's shopping information), which indicates that it cannot be used for secure online shopping as the authors expected. Accordingly, an improvement of this protocol, which could resist the controller's attack, is proposed. In addition, we present another protocol which is more appropriate for online shopping. Finally, a discussion about the difference in detail of the quantum secure direct communication process between regular quantum communications and online shopping is given.
Spread of resistant gram negatives in a Sri Lankan intensive care unit.
Tissera, Kavinda; Liyanapathirana, Veranja; Dissanayake, Nilanthi; Pinto, Vasanthi; Ekanayake, Asela; Tennakoon, Manjula; Adasooriya, Dinuka; Nanayakkara, Dulmini
2017-07-11
Infections with multi drug resistant (MDR) organisms are a major problem in intensive care units (ICUs). Proper infection control procedures are mandatory to combat the spread of resistant organisms within ICUs. Well stablished surveillance programmes will enhance the adherence of the staff to infection control protocols. The study was conducted to assess the feasibility of using basic molecular typing methods and routine hospital data for laboratory surveillance of resistance organisms in resource limited settings. A retrospective study was conducted using consecutive Gram negative isolates obtained from an ICU over a six month period. Antibiotic sensitivity patterns and random amplified polymorphic DNA (RAPD) based typing was performed on the given isolates. Of the seventy isolates included in the study, seven were E.coli. All E.coli were MDRs and Extended Spectrum β lactamse (ESBL) producers carrying bla CTX-M . Fourteen isolates were K.pneumoniae, and all were MDRs and ESBL producers. All K.pneumoniae harboured bla SHV while 13 harboured bla CTX-M . The MDR rate among P.aeruginosa was 13% (n=15) while all acinetobacters (n=30) were MDRs. Predominant clusters were identified within all four types of Gram negatives using RAPD and the ICU stay of patients overlapped temporally. We propose that simple surveillance methods like RAPD based typing and basic hospital data can be used to convince hospital staff to adhere to infection control protocols more effectively, in low and middle income countries.
Peng, Linda X; Wallace, Morgan; Andaloro, Bridget; Fallon, Dawn; Fleck, Lois; Delduco, Dan; Tice, George
2011-01-01
The BAX System PCR assay for Salmonella detection in foods was previously validated as AOAC Research Institute (RI) Performance Tested Method (PTM) 100201. New studies were conducted on beef and produce using the same media and protocol currently approved for the BAX System PCR assay for E. coli O157:H7 multiplex (MP). Additionally, soy protein isolate was tested for matrix extension using the U.S. Food and Drug Administration-Bacteriological Analytical Manual (FDA-BAM) enrichment protocols. The studies compared the BAX System method to the U.S. Department of Agriculture culture method for detecting Salmonella in beef and the FDA-BAM culture method for detecting Salmonella in produce and soy protein isolate. Method comparison studies on low-level inoculates showed that the BAX System assay for Salmonella performed as well as or better than the reference method for detecting Salmonella in beef and produce in 8-24 h enrichment when the BAX System E. coli O157:H7 MP media was used, and soy protein isolate in 20 h enrichment with lactose broth followed by 3 h regrowth in brain heart infusion broth. An inclusivity panel of 104 Salmonella strains with diverse serotypes was tested by the BAX System using the proprietary BAX System media and returned all positive results. Ruggedness factors involved in the enrichment phase were also evaluated by testing outside the specified parameters, and none of the factors examined affected the performance of the assay.
Sunstrom, Rachel; Hamilton, Nicholas; Fialkowski, Elizabeth; Lofberg, Katrine; McKee, Julie; Sims, Thomas; Krishnaswami, Sanjay; Azarow, Kenneth
2016-05-01
A protocol for laparoscopic gastrostomy placement was implemented which specified perioperative antibiotics, feeding regimens, and discharge criteria. Our hypothesis was that hospital cost could be decreased, whereas at the same time improving or maintaining patient outcomes. Data were collected on consecutive patients beginning 6 months after implementation of our protocol. We recorded surgeon compliance, patient outcomes (as defined by 30-day NSQIP complication rates), and cost of initial hospitalization, which was then compare to a 6-month historical control period. Our control group n = 26 and protocol group n = 39. Length of stay was shorter in the protocol group (P ≤ .05 by nonparametric analysis). The complication rate was similar in both groups (23% control vs 15% protocol, P = .43). Initial hospital costs were not different. Surgeon compliance to protocol was 82%. A standard protocol is achievable for gastrostomy tube management. After implementation of our protocol, we were able to show a significant decrease in length of stay, whereas maintaining quality. Copyright © 2016 Elsevier Inc. All rights reserved.
Isolation of total RNA from yeast cell cultures.
Ares, Manuel
2012-10-01
This article describes two procedures for isolating total RNA from yeast cell cultures. The first allows the convenient isolation of total RNA from early log-phase cultures (vegetative cells). RNA isolated in this way is intact and sufficiently pure for use in microarray experiments, primer extension, and RNase protection mapping. With additional treatment to remove contaminating genomic DNA, the preparation is suitable for reverse transcription-polymerase chain reaction (RT-PCR), quantitative PCR (qPCR), cDNA library construction, high-throughput sequencing of RNA, or other manipulations. However, compared to vegetative cells, the isolation of RNA from cells late in meiosis (asci and ascospores) requires additional effort. This is because a tough cell wall composed of heavily cross-linked polysaccharides and proteins is built around the four spores during meiosis and ascospore development. Therefore, an alternative protocol is presented for extracting RNA from cells late in meiosis. This alternative may also be preferable for cells from stationary cultures or from yeast strains and other fungal species isolated from the environment.
Schindler, Jens; Nothwang, Hans Gerd
2009-01-01
The plasma membrane separates the cell-interior from the cell's environment. To maintain homeostatic conditions and to enable transfer of information, the plasma membrane is equipped with a variety of different proteins such as transporters, channels, and receptors. The kind and number of plasma membrane proteins are a characteristic of each cell type. Owing to their location, plasma membrane proteins also represent a plethora of drug targets. Their importance has entailed many studies aiming at their proteomic identification and characterization. Therefore, protocols are required that enable their purification in high purity and quantity. Here, we report a protocol, based on aqueous polymer two-phase systems, which fulfils these demands. Furthermore, the protocol is time-saving and protects protein structure and function.
Assi, Mohamad; Dauguet, Nicolas; Jacquemin, Patrick
2018-01-01
The isolation of ribonucleic acid (RNA) suitable for gene expression studies is challenging in the pancreas, due to its high ribonuclease activity. This is even more complicated during pancreatitis, a condition associated with inflammation and fibrosis. Our aim was to implement a time-effective and reproducible protocol to isolate high quality RNA from specific pancreatic cell subtypes, in normal and inflammatory conditions. We used two genetically engineered mouse models (GEMM), Ela-CreER/YFP and Sox9-CreER/YFP, to isolate acinar and ductal cells, respectively. To induce pancreatitis, mice received a caerulein treatment (125 μg/kg) for 8 and 72 h. We alternatively used EGTA and calcium buffers that contain collagenase P (0.6 mg/mL) to rapidly digest the pancreas into individual cells. Most of the cells from normal and injured pancreas were single-dissociated, exhibited a round morphology and did not incorporate trypan blue dye. Cell suspensions from Ela- and Sox9-CreER/YFP pancreas were then sorted by flow cytometry to isolate the YFP-positive acinar and ductal cells, respectively. Sorted cells kept a round shape and emitted fluorescence detected by the 38 HE green fluorescence filter. RNA was isolated by column-based purification approach. The RNA integrity number (RIN) was high in sorted acinar cell fractions treated with or without caerulein (8.6 ± 0.17 and 8.4 ± 0.09, respectively), compared to the whole pancreas fraction (4.8 ± 1.1). Given the low number of sorted ductal cells, the RIN value was slightly lower compared to acini (7.4 ± 0.4). Quantitative-PCR experiments indicated that sorted acinar and ductal cells express the specific acinar and ductal markers, respectively. Additionally, RNA preparations from caerulein-treated acinar cells were free from significant contamination with immune cell RNA. We thus validated the DIE (Digestion, Isolation, and Extraction)-RNA tool as a reproducible and efficient protocol to isolate pure acinar and ductal cells in vivo and to extract high quality RNA from these cells. PMID:29535635
Assi, Mohamad; Dauguet, Nicolas; Jacquemin, Patrick
2018-01-01
The isolation of ribonucleic acid (RNA) suitable for gene expression studies is challenging in the pancreas, due to its high ribonuclease activity. This is even more complicated during pancreatitis, a condition associated with inflammation and fibrosis. Our aim was to implement a time-effective and reproducible protocol to isolate high quality RNA from specific pancreatic cell subtypes, in normal and inflammatory conditions. We used two genetically engineered mouse models (GEMM), Ela-CreER/YFP and Sox9-CreER/YFP, to isolate acinar and ductal cells, respectively. To induce pancreatitis, mice received a caerulein treatment (125 μg/kg) for 8 and 72 h. We alternatively used EGTA and calcium buffers that contain collagenase P (0.6 mg/mL) to rapidly digest the pancreas into individual cells. Most of the cells from normal and injured pancreas were single-dissociated, exhibited a round morphology and did not incorporate trypan blue dye. Cell suspensions from Ela- and Sox9-CreER/YFP pancreas were then sorted by flow cytometry to isolate the YFP-positive acinar and ductal cells, respectively. Sorted cells kept a round shape and emitted fluorescence detected by the 38 HE green fluorescence filter. RNA was isolated by column-based purification approach. The RNA integrity number (RIN) was high in sorted acinar cell fractions treated with or without caerulein (8.6 ± 0.17 and 8.4 ± 0.09, respectively), compared to the whole pancreas fraction (4.8 ± 1.1). Given the low number of sorted ductal cells, the RIN value was slightly lower compared to acini (7.4 ± 0.4). Quantitative-PCR experiments indicated that sorted acinar and ductal cells express the specific acinar and ductal markers, respectively. Additionally, RNA preparations from caerulein-treated acinar cells were free from significant contamination with immune cell RNA. We thus validated the DIE (Digestion, Isolation, and Extraction)-RNA tool as a reproducible and efficient protocol to isolate pure acinar and ductal cells in vivo and to extract high quality RNA from these cells.
Bustamante, Ana V.; Lucchesi, Paula M.A.; Parma, Alberto E.
2009-01-01
The aim of this work was to adapt described MLVA protocols to the molecular typing and characterization of VTEC O157:H7 isolates from Argentina. Nine VNTR loci were amplified by PCR showing diversity values from 0.49 to 0.73. Nine MLVA profiles were observed and the cluster analysis indicated both unrelated and closely related VTEC O157:H7 strains. In spite of the limited number of isolates studied, the panel of VNTR used made it possible to perform a first approach of the high genetic diversity of native strains of O157:H7 by MLVA. PMID:24031443
New phytochemicals as potential human anti-aging compounds: Reality, promise, and challenges.
Corrêa, Rúbia C G; Peralta, Rosane M; Haminiuk, Charles W I; Maciel, Giselle Maria; Bracht, Adelar; Ferreira, Isabel C F R
2018-04-13
Aging is an inevitable process influenced by genetic, lifestyle, and environmental factors. Indirect evidence shows that several phytochemicals can have anti-aging capabilities, although direct evidence in this field is still limited. This report aims to provide a critical review on aspects related to the use of novel phytochemicals as anti-aging agents, to discuss the obstacles found when performing most anti-aging study protocols in humans, and to analyze future perspectives. In addition to the extensively studied resveratrol, epicatechin, quercetin, and curcumin, new phytochemicals have been reported to act as anti-aging agents, such as the amino acid L-theanine isolated from green tea, and the lignans arctigenin and matairesinol isolated from Arctium lappa seeds. Furthermore, this review discusses the application of several new extracts rich in phytochemicals with potential use in anti-aging therapies. Finally, this review also discusses the most important biomarkers to test anti-aging interventions, the necessity of conducting epidemiological studies and the need of clinical trials with adequate study protocols for humans.
Phenotyping sensory nerve endings in vitro in the mouse
Zimmermann, Katharina; Hein, Alexander; Hager, Ulrich; Kaczmarek, Jan Stefan; Turnquist, Brian P; Clapham, David E; Reeh, Peter W
2014-01-01
This protocol details methods to identify and record from cutaneous primary afferent axons in an isolated mammalian skin–saphenous nerve preparation. The method is based on extracellular recordings of propagated action potentials from single-fiber receptive fields. Cutaneous nerve endings show graded sensitivities to various stimulus modalities that are quantified by adequate and controlled stimulation of the superfused skin with heat, cold, touch, constant punctate pressure or chemicals. Responses recorded from single-fibers are comparable with those obtained in previous in vivo experiments on the same species. We describe the components and the setting-up of the basic equipment of a skin–nerve recording station (few days), the preparation of the skin and the adherent saphenous nerve in the mouse (15–45 min) and the isolation and recording of neurons (approximately 1–3 h per recording). In addition, stimulation techniques, protocols to achieve single-fiber recordings, issues of data acquisition and action potential discrimination are discussed in detail. PMID:19180088
Isolation of cell-free bacterial inclusion bodies.
Rodríguez-Carmona, Escarlata; Cano-Garrido, Olivia; Seras-Franzoso, Joaquin; Villaverde, Antonio; García-Fruitós, Elena
2010-09-17
Bacterial inclusion bodies are submicron protein clusters usually found in recombinant bacteria that have been traditionally considered as undesirable products from protein production processes. However, being fully biocompatible, they have been recently characterized as nanoparticulate inert materials useful as scaffolds for tissue engineering, with potentially wider applicability in biomedicine and material sciences. Current protocols for inclusion body isolation from Escherichia coli usually offer between 95 to 99% of protein recovery, what in practical terms, might imply extensive bacterial cell contamination, not compatible with the use of inclusion bodies in biological interfaces. Using an appropriate combination of chemical and mechanical cell disruption methods we have established a convenient procedure for the recovery of bacterial inclusion bodies with undetectable levels of viable cell contamination, below 10⁻¹ cfu/ml, keeping the particulate organization of these aggregates regarding size and protein folding features. The application of the developed protocol allows obtaining bacterial free inclusion bodies suitable for use in mammalian cell cultures and other biological interfaces.
Mesenchymal stem cells: biological characteristics and potential clinical applications.
Kassem, Moustapha
2004-01-01
Mesenchymal stem cells (MSC) are clonogenic, non-hematpoietic stem cells present in the bone marrow and are able to differentiate into multiple mesoderm-type cell lineages, for example, osteoblasts, chondrocytes, endothelial-cells and also non-mesoderm-type lineages, for example, neuronal-like cells. Several methods are currently available for isolation of the MSC based on their physical and physico-chemical characteristics, for example, adherence to plastics or other extracellular matrix components. Because of the ease of their isolation and their extensive differentiation potential, MSC are among the first stem cell types to be introduced in the clinic. Several studies have demonstrated the possible use of MSC in systemic transplantation for systemic diseases, local implantation for local tissue defects, as a vehicle for genes in gene therapy protocols or to generate transplantable tissues and organs in tissue engineering protocols. Before their widespread use in therapy, methods allowing the generation of large number of cells without affecting their differentiation potential as well as technologies that overcome immunological rejection (in case allogenic transplantation) must be developed.
A quantitative telomeric chromatin isolation protocol identifies different telomeric states
NASA Astrophysics Data System (ADS)
Grolimund, Larissa; Aeby, Eric; Hamelin, Romain; Armand, Florence; Chiappe, Diego; Moniatte, Marc; Lingner, Joachim
2013-11-01
Telomere composition changes during tumourigenesis, aging and in telomere syndromes in a poorly defined manner. Here we develop a quantitative telomeric chromatin isolation protocol (QTIP) for human cells, in which chromatin is cross-linked, immunopurified and analysed by mass spectrometry. QTIP involves stable isotope labelling by amino acids in cell culture (SILAC) to compare and identify quantitative differences in telomere protein composition of cells from various states. With QTIP, we specifically enrich telomeric DNA and all shelterin components. We validate the method characterizing changes at dysfunctional telomeres, and identify and validate known, as well as novel telomere-associated polypeptides including all THO subunits, SMCHD1 and LRIF1. We apply QTIP to long and short telomeres and detect increased density of SMCHD1 and LRIF1 and increased association of the shelterins TRF1, TIN2, TPP1 and POT1 with long telomeres. Our results validate QTIP to study telomeric states during normal development and in disease.
The advantages of "Dance-group" for psychotic patients.
Tavormina, Romina; Tavormina, Maurilio Giuseppe Maria; Nemoianni, Eugenio
2014-11-01
Psychosocial rehabilitation and in particular group dances allow the recovery of lost or compromised ability of patients with mental illness, and they facilitate their reintegration into the social context. The dance group has enabled users of the Day Centre of the Unit of Mental Health Torre del Greco ASL NA 3 south to achieve the objectives of rehabilitation such as: taking care of themselves, of their bodies and their interests, improving self-esteem , the management of pathological emotions, socialization and integration, overcoming the psychotic closing and relational isolation. In particular, patients with schizophrenia, psychotic and mood disorders had a concrete benefit from such rehabilitation activities, facilitating interpersonal relationships, therapy compliance and significantly improved mood, quality of life, providing them with the rhythm and the security in their relationship with each other. The dance group and for some individuals, also psychotherapy and drug therapy, have facilitated social inclusion, improved the quality of life and cured their diseases. The work is carrying out in a group with patients, practitioners, family members, volunteers, social community workers, following the operating departmental protocols. Using the chorus group "Sing that you go" as an operational tool for psychosocial rehabilitation and therapeutic element we promote the psychological well-being and the enhancement of mood.
Gleicher, Yehoshua; Mosko, Jeffrey David; McGhee, Irene
2017-01-01
Handovers from the cardiovascular operating room (CVOR) to the cardiovascular intensive care unit (CVICU) are complex processes involving the transfer of information, equipment and responsibility, at a time when the patient is most vulnerable. This transfer is typically variable in structure, content and execution. This variability can lead to the omission and miscommunication of critical information leading to patient harm. We set out to improve the quality of patient handover from the CVOR to the CVICU by introducing a standardised handover protocol. This study is an interventional time-series study over a 4-month period at an adult cardiac surgery centre. A standardised handover protocol was developed using quality improvement methodologies. The protocol included a handover content checklist and introduction of a formal 'sterile cockpit' timeout. Implementation of the protocol was refined using monthly iterative Plan-Do-Study-Act. The primary outcome was the quality of handovers, measured by a Handover Score, comprising handover content, teamwork and patient care planning indicators. Secondary outcomes included handover duration, adherence to the standardised handover protocol and handover team satisfaction surveys. 37 handovers were observed (6 pre intervention and 31 post intervention). The mean handover score increased from 6.5 to 14.0 (maximum 18 points). Specific improvements included fewer handover interruptions and more frequent postoperative patient care planning. Average handover duration increased slightly from 2:40 to 2:57 min. Caregivers noted improvements in teamwork, content received and patient care planning. The majority (>95%) agreed that the intervention was a valuable addition to the CVOR to CVICU handover process. Implementation of a standardised handover protocol for postcardiac surgery patients was associated with fewer interruptions during handover, more reliable transfer of critical content and improved patient care planning.
Straight Talk About Birth Control: A Contraceptive Education Protocol for Home Care.
Schoenberg, Leslie
Home healthcare providers play a critical role in the prevention of unintended pregnancies by providing evidence-based contraception education during home visits. This article describes an innovative and comprehensive contraception protocol that was developed for Nurse-Family Partnership to improve contraception education for home healthcare patients. The protocol focused on increasing uptake of long-acting reversible contraception (LARC) for high-risk prenatal and postpartum home healthcare patients. The protocol was designed to reduce early subsequent pregnancies and thereby improve outcomes for mothers and their infants. An evidence-based translation project was designed and piloted in three California counties. The protocol consisted of a contraception education module for nurses and a patient education toolkit. The toolkit included an interactive patient education workbook emphasizing LARC methods for nurses to complete with their patients along with other teaching tools. The project was evaluated using pre- and posttest surveys that measured changes in nurses' knowledge, attitudes, and practice before, after, and 2 months after implementation. Outcomes revealed the following statistically significant results: (a) nurses' knowledge doubled at the first posttest and persisted at 2 months, (b) nurses' attitudes improved on two of the three measures, and (c) there was a 17.7% increase in the frequency of LARC birth control education 2 months after implementation. An evidence-based contraception protocol can promote acceptance of LARC methods and improve home healthcare clinician comfort with and frequency of birth control education.
Yang, Lei; Chen, Shouming; Yang, Di; Li, Jiajin; Wu, Taixiang; Zuo, Yunxia
2018-05-15
To learn about the overall quality of clinical anaesthesia study protocols from the Chinese Clinical Trials Registry and to discuss the way to improve study protocol quality. We defined completeness of each sub-item in SPIRIT as N/A (not applicable) or with a score of 0, 1, or 2. For each protocol, we calculated the proportion of adequately reported items (score = 2 and N/A) and unreported items (score = 0). Protocol quality was determined according to the proportion of reported items, with values >50% indicating high quality. Protocol quality was determined according to the proportion of reported items. For each sub-item in SPIRIT, we calculated the adequately reported rate (percentage of all protocols with score 2 and NA on one sub-item) as well as the unreported rate (percentage of all protocols with score 0 on one sub-item). Total 126 study protocols were available for assessment. Among these, 88.1% were assessed as being of low quality. By comparison, the percentage of low-quality protocols was 88.9% after the publication of the SPIRIT statement. Among the 51 SPIRIT sub-items, 18 sub-items had an unreported rate above 90% while 16 had a higher adequately reported rate than an unreported rate. The overall quality of clinical anaesthesia study protocols registered in the ChiCTR was poor. A mandatory protocol upload and self-check based on the SPIRIT statement during the trial registration process may improve protocol quality in the future.
Koncsos, Gábor; Varga, Zoltán V; Baranyai, Tamás; Ferdinandy, Péter; Schulz, Rainer; Giricz, Zoltán; Boengler, Kerstin
In the heart, subsarcolemmal (SSM), interfibrillar (IFM) and perinuclear mitochondria represent three subtypes of mitochondria. The most commonly used protease during IFM isolation is the nagarse, however, its effect on the detection of mitochondrial proteins is still unclear. Therefore, we investigated whether nagarse treatment influences the quantification of mitochondrial proteins. SSM and IFM were isolated from hearts of mice and rats. During IFM isolation, nagarse activity was either stopped by centrifugation (common protocol, IFM+N) or inhibited by phenylmethylsulfonyl fluoride (PMSF, IFM+N+I). The amounts of proteins located in different mitochondrial compartments (outer membrane: mitofusin 1 (MFN1) and 2 (MFN2); intermembrane space: p66shc; inner membrane (connexin 43 (Cx43)), and of protein deglycase DJ-1 were determined by Western blot. MFN2 and Cx43 were found predominantly in SSM isolated from mouse and rat hearts. MFN1 and p66shc were present in similar amounts in SSM and IFM+N, whereas the level of DJ-1 was higher in IFM+N compared to SSM. In IFM+N+I samples from mice, the amount of MFN2, but not that of Cx43 increased. Nagarse or nagarse inhibition by PMSF had no effect on oxygen consumption of SSM or IFM. Whereas the use of the common protocol indicates the localization of MFN2 predominantly in SSM, the inhibition of nagarse by PMSF increases the signal of MFN2 in IFM to that of in SSM, indicating an underestimation of MFN2 in IFM. Therefore, protease sensitivity should be considered when assessing distribution of mitochondrial proteins using nagarse-based isolation. Copyright © 2018 Elsevier Inc. All rights reserved.
Concurrent Isolation of 3 Distinct Cardiac Stem Cell Populations From a Single Human Heart Biopsy.
Monsanto, Megan M; White, Kevin S; Kim, Taeyong; Wang, Bingyan J; Fisher, Kristina; Ilves, Kelli; Khalafalla, Farid G; Casillas, Alexandria; Broughton, Kathleen; Mohsin, Sadia; Dembitsky, Walter P; Sussman, Mark A
2017-07-07
The relative actions and synergism between distinct myocardial-derived stem cell populations remain obscure. Ongoing debates on optimal cell population(s) for treatment of heart failure prompted implementation of a protocol for isolation of multiple stem cell populations from a single myocardial tissue sample to develop new insights for achieving myocardial regeneration. Establish a robust cardiac stem cell isolation and culture protocol to consistently generate 3 distinct stem cell populations from a single human heart biopsy. Isolation of 3 endogenous cardiac stem cell populations was performed from human heart samples routinely discarded during implantation of a left ventricular assist device. Tissue explants were mechanically minced into 1 mm 3 pieces to minimize time exposure to collagenase digestion and preserve cell viability. Centrifugation removes large cardiomyocytes and tissue debris producing a single cell suspension that is sorted using magnetic-activated cell sorting technology. Initial sorting is based on tyrosine-protein kinase Kit (c-Kit) expression that enriches for 2 c-Kit + cell populations yielding a mixture of cardiac progenitor cells and endothelial progenitor cells. Flowthrough c-Kit - mesenchymal stem cells are positively selected by surface expression of markers CD90 and CD105. After 1 week of culture, the c-Kit + population is further enriched by selection for a CD133 + endothelial progenitor cell population. Persistence of respective cell surface markers in vitro is confirmed both by flow cytometry and immunocytochemistry. Three distinct cardiac cell populations with individualized phenotypic properties consistent with cardiac progenitor cells, endothelial progenitor cells, and mesenchymal stem cells can be successfully concurrently isolated and expanded from a single tissue sample derived from human heart failure patients. © 2017 American Heart Association, Inc.
Analyses of Mitochondrial Calcium Influx in Isolated Mitochondria and Cultured Cells.
Maxwell, Joshua T; Tsai, Chin-Hsien; Mohiuddin, Tahmina A; Kwong, Jennifer Q
2018-04-27
Ca 2+ handling by mitochondria is a critical function regulating both physiological and pathophysiological processes in a broad spectrum of cells. The ability to accurately measure the influx and efflux of Ca 2+ from mitochondria is important for determining the role of mitochondrial Ca 2+ handling in these processes. In this report, we present two methods for the measurement of mitochondrial Ca 2+ handling in both isolated mitochondria and cultured cells. We first detail a plate reader-based platform for measuring mitochondrial Ca 2+ uptake using the Ca 2+ sensitive dye calcium green-5N. The plate reader-based format circumvents the need for specialized equipment, and the calcium green-5N dye is ideally suited for measuring Ca 2+ from isolated tissue mitochondria. For our application, we describe the measurement of mitochondrial Ca 2+ uptake in mitochondria isolated from mouse heart tissue; however, this procedure can be applied to measure mitochondrial Ca 2+ uptake in mitochondria isolated from other tissues such as liver, skeletal muscle, and brain. Secondly, we describe a confocal microscopy-based assay for measurement of mitochondrial Ca 2+ in permeabilized cells using the Ca 2+ sensitive dye Rhod-2/AM and imaging using 2-dimensional laser-scanning microscopy. This permeabilization protocol eliminates cytosolic dye contamination, allowing for specific recording of changes in mitochondrial Ca 2+ . Moreover, laser-scanning microscopy allows for high frame rates to capture rapid changes in mitochondrial Ca 2+ in response to various drugs or reagents applied in the external solution. This protocol can be applied to measure mitochondrial Ca 2+ uptake in many cell types including primary cells such as cardiac myocytes and neurons, and immortalized cell lines.
Herrera Cano, Natividad; Uranga, Jorge G; Nardi, Mónica; Procopio, Antonio; Wunderlin, Daniel A
2016-01-01
An improved and greener protocol for the synthesis of benzimidazole derivatives, starting from o-phenylenediamine, with different aldehydes is reported. Double-condensation products were selectively obtained when Er(OTf)3 was used as the catalyst in the presence of electron-rich aldehydes. Conversely, the formation of mono-condensation products was the preferred path in absence of this catalyst. One of the major advantages of these reactions was the formation of a single product, avoiding extensive isolation and purification of products, which is frequently associated with these reactions. Theoretical calculations helped to understand the different reactivity established for these reactions. Thus, we found that the charge density on the oxygen of the carbonyl group has a significant impact on the reaction pathway. For instance, electron-rich aldehydes better coordinate to the catalyst, which favours the addition of the amine group to the carbonyl group, therefore facilitating the formation of double-condensation products. Reactions with aliphatic or aromatic aldehydes were possible, without using organic solvents and in a one-pot procedure with short reaction time (2–5 min), affording single products in excellent yields (75–99%). This convenient and eco-friendly methodology offers numerous benefits with respect to other protocols reported for similar compounds. PMID:28144309
Ferret, Yann; Caillault, Aurélie; Sebda, Shéhérazade; Duez, Marc; Grardel, Nathalie; Duployez, Nicolas; Villenet, Céline; Figeac, Martin; Preudhomme, Claude; Salson, Mikaël; Giraud, Mathieu
2016-05-01
High-throughput sequencing (HTS) is considered a technical revolution that has improved our knowledge of lymphoid and autoimmune diseases, changing our approach to leukaemia both at diagnosis and during follow-up. As part of an immunoglobulin/T cell receptor-based minimal residual disease (MRD) assessment of acute lymphoblastic leukaemia patients, we assessed the performance and feasibility of the replacement of the first steps of the approach based on DNA isolation and Sanger sequencing, using a HTS protocol combined with bioinformatics analysis and visualization using the Vidjil software. We prospectively analysed the diagnostic and relapse samples of 34 paediatric patients, thus identifying 125 leukaemic clones with recombinations on multiple loci (TRG, TRD, IGH and IGK), including Dd2/Dd3 and Intron/KDE rearrangements. Sequencing failures were halved (14% vs. 34%, P = 0.0007), enabling more patients to be monitored. Furthermore, more markers per patient could be monitored, reducing the probability of false negative MRD results. The whole analysis, from sample receipt to clinical validation, was shorter than our current diagnostic protocol, with equal resources. V(D)J recombination was successfully assigned by the software, even for unusual recombinations. This study emphasizes the progress that HTS with adapted bioinformatics tools can bring to the diagnosis of leukaemia patients. © 2016 John Wiley & Sons Ltd.
Herrera Cano, Natividad; Uranga, Jorge G; Nardi, Mónica; Procopio, Antonio; Wunderlin, Daniel A; Santiago, Ana N
2016-01-01
An improved and greener protocol for the synthesis of benzimidazole derivatives, starting from o -phenylenediamine, with different aldehydes is reported. Double-condensation products were selectively obtained when Er(OTf) 3 was used as the catalyst in the presence of electron-rich aldehydes. Conversely, the formation of mono-condensation products was the preferred path in absence of this catalyst. One of the major advantages of these reactions was the formation of a single product, avoiding extensive isolation and purification of products, which is frequently associated with these reactions. Theoretical calculations helped to understand the different reactivity established for these reactions. Thus, we found that the charge density on the oxygen of the carbonyl group has a significant impact on the reaction pathway. For instance, electron-rich aldehydes better coordinate to the catalyst, which favours the addition of the amine group to the carbonyl group, therefore facilitating the formation of double-condensation products. Reactions with aliphatic or aromatic aldehydes were possible, without using organic solvents and in a one-pot procedure with short reaction time (2-5 min), affording single products in excellent yields (75-99%). This convenient and eco-friendly methodology offers numerous benefits with respect to other protocols reported for similar compounds.
Gonzalez García, Eric; Ressmann, Anna K; Gaertner, Peter; Zirbs, Ronald; Mach, Robert L; Krska, Rudolf; Bica, Katharina; Brunner, Kurt
2014-12-01
To date, the extraction of genomic DNA is considered a bottleneck in the process of genetically modified organisms (GMOs) detection. Conventional DNA isolation methods are associated with long extraction times and multiple pipetting and centrifugation steps, which makes the entire procedure not only tedious and complicated but also prone to sample cross-contamination. In recent times, ionic liquids have emerged as innovative solvents for biomass processing, due to their outstanding properties for dissolution of biomass and biopolymers. In this study, a novel, easily applicable, and time-efficient method for the direct extraction of genomic DNA from biomass based on aqueous-ionic liquid solutions was developed. The straightforward protocol relies on extraction of maize in a 10 % solution of ionic liquids in aqueous phosphate buffer for 5 min at room temperature, followed by a denaturation step at 95 °C for 10 min and a simple filtration to remove residual biopolymers. A set of 22 ionic liquids was tested in a buffer system and 1-ethyl-3-methylimidazolium dimethylphosphate, as well as the environmentally benign choline formate, were identified as ideal candidates. With this strategy, the quality of the genomic DNA extracted was significantly improved and the extraction protocol was notably simplified compared with a well-established method.
Noda, Yoshifumi; Goshima, Satoshi; Kojima, Toshihisa; Kawaguchi, Shimpei; Kawada, Hiroshi; Kawai, Nobuyuki; Koyasu, Hiromi; Matsuo, Masayuki; Bae, Kyongtae T
2017-04-01
To evaluate the value of adding single-shot balanced turbo field-echo (b-TFE) sequence to conventional magnetic resonance cholangiopancreatography (MRCP) for the detection of common bile duct (CBD) stone. One hundred thirty-seven consecutive patients with suspected CBD stone underwent MRCP including single-shot b-TFE sequence. Twenty-five patients were confirmed with CBD stone by endoscopic retrograde cholangiopancreatography or ultrasonography. Two radiologists reviewed two image protocols: protocol A (conventional MRCP protocol: unenhanced T1-, T2-, and respiratory-triggered three-dimensional fat-suppressed single-shot turbo spin-echo MRCP sequence) and protocol B (protocol A plus single-shot b-TFE sequence). The sensitivity, specificity, positive (PPV) and negative predictive value (NPV), and area under the receiver-operating-characteristic (ROC) curve (AUC) for the detection of CBD stone were compared. The sensitivity (72%) and NPV (94%) were the same between the two protocols. However, protocol B was greater in the specificity (99%) and PPV (94%) than protocol A (92% and 67%, respectively) (P = 0.0078 and 0.031, respectively). The AUC was significantly greater for protocol B (0.93) than for protocol A (0.86) (P = 0.026). Inclusion of single-shot b-TFE sequence to conventional MRCP significantly improved the specificity and PPV for the detection of CBD stone.
An RNA isolation system for plant tissues rich in secondary metabolites
2011-01-01
Background Secondary metabolites are reported to interfere with the isolation of RNA particularly with the recipes that use guanidinium-based salt. Such interference was observed in isolation of RNA with medicinal plants rheum (Rheum australe) and arnebia (Arnebia euchroma). A rapid and less cumbersome system for isolation of RNA was essential to facilitate any study related to gene expression. Findings An RNA isolation system free of guanidinium salt was developed that successfully isolated RNA from rheum and arnebia. The method took about 45 min and was successfully evaluated on twenty one tissues with varied secondary metabolites. The A260/280 ratio ranged between 1.8 - 2.0 with distinct 28 S and 18 S rRNA bands visible on a formaldehyde-agarose gel. Conclusions The present manuscript describes a rapid protocol for isolation of RNA, which works well with all the tissues examined so far. The remarkable feature was the success in isolation of RNA with those tissues, wherein the most commonly used methods failed. Isolated RNA was amenable to downstream applications such as reverse transcription-polymerase chain reaction (RT-PCR), differential display (DD), suppression subtractive hybridization (SSH) library construction, and northern hybridization. PMID:21443767
Speranza, Barbara; Bevilacqua, Antonio; Corbo, Maria Rosaria; Sinigaglia, Milena
2017-07-01
The performances of four autochthonous isolates of Lactobacillus plantarum were assessed to study the most important variables acting on acidification and to propose a possible step-by-step approach for the validation at laboratory scale. This main topic was addressed through three intermediate steps: (1) evaluation of acidification in liquid and solid media, as a function of salt, nitrites, nitrates, lactose, pepper and temperature; (2) assessing acidification in a pork-meat preparation; and (3) designing a protocol to improve the performances at sub-optimal temperatures. The concentration of the ingredients and the temperature were combined through a 3 k-p Fractional Factorial Design. Acidification and viable count were assessed and modelled through a multi-factorial ANOVA. In model systems acidification was affected by lactose and was maximum (ΔpH of ca. 2.8-3.0) in the combinations containing 0.4% lactose, 250 mg kg -1 nitrates or 150 mg kg -1 nitrites, 5% salt, and at 30 °C. Solid media caused a higher acidification. In the pork meat preparation, the effect of salt and nitrites was significant. At 10 °C the strains could not reduce pH, but this ability could be induced using an adaptation step. Acidification was affected by lactose in the model system, whereas in meat preparation the other variables were significant. In addition, a protocol to improve acidification at 10 °C was optimised. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.
Helping Families Cope with the Severe Stress of Dravet Syndrome.
Camfield, Peter; Camfield, Carol; Nolan, Kathleen
2016-06-01
A child with Dravet syndrome shakes family life to the core. Dravet syndrome usually has three phases: (1) up to 1-1½ years: with episodes of febrile status epilepticus but normal development; (2) age 1½ to ~6-10 years: with frequent seizures of varying types, developmental stagnation, behavioural and sleep problems; (3) after ~10 years: improvement in seizures, deteriorating gait, intellectual disability but some developmental gains. Complete seizure control is rare-simply prescribing medication is inadequate to help families. Based on structured interviews with 24 families and confirmed by more informal discussions with other families, we suggest strategies for coping with this catastrophe. A child with Dravet syndrome usually means that one parent cannot work-financial pressures should be anticipated. In Stage 1, the approach to status should include a written protocol. An indwelling catheter for rapid venous access may be helpful. In Stage 2, assistance finding qualified babysitters is required, and the extended family needs encouragement to help. Appropriate equipment, rescue medication and protocols should travel with the child. Siblings may benefit from a system of one parent "on call." An internet support group provides an invaluable lifeline. In Stage 3, family isolation may be extreme-respite care and personal time for parents are important. Death from status, accidents and SUDEP (sudden unexplained death in epilepsy) occurs in 15%. Fear of SUDEP needs to be addressed. Moving from paediatric to adult care is frightening; an epilepsy transition clinic is useful. Attention to these realities may improve the quality of life for both child and family.
NASA Technical Reports Server (NTRS)
Zhou, Xiaoming (Inventor); Baras, John S. (Inventor)
2010-01-01
The present invention relates to an improved communications protocol which increases the efficiency of transmission in return channels on a multi-channel slotted Alohas system by incorporating advanced error correction algorithms, selective retransmission protocols and the use of reserved channels to satisfy the retransmission requests.
Gigabit Ethernet: A Technical Assessment.
ERIC Educational Resources Information Center
Axner, David
1997-01-01
Describes gigabit ethernet for LAN (local area network) technology that will expand ethernet bandwidth. Technical details are discussed, including protocol stacks, optical fiber, deployment strategy for performance improvement, ATM (Asynchronous Transfer Mode), real-time protocol, reserve reservation protocol, and standards. (LRW)
Effects of Myofascial Release in Nonspecific Chronic Low Back Pain: A Randomized Clinical Trial.
Arguisuelas, María D; Lisón, Juan Francisco; Sánchez-Zuriaga, Daniel; Martínez-Hurtado, Isabel; Doménech-Fernández, Julio
2017-05-01
Double-blind, randomized parallel sham-controlled trial with concealed allocation and intention-to treat analysis. To investigate the effects of an isolate myofascial release (MFR) protocol on pain, disability, and fear-avoidance beliefs in patients with chronic low back pain (CLBP). MFR is a form of manual medicine widely used by physiotherapists in the management of different musculoskeletal pathologies. Up to this moment, no previous studies have reported the effects of an isolated MFR treatment in patients with CLBP. Fifty-four participants, with nonspecific CLBP, were randomized to MFR group (n = 27) receiving four sessions of myofascial treatment, each lasting 40 minutes, and to control group (n = 27) receiving a sham MFR. Variables studied were pain measured by means Short Form McGill Pain Questionnaire (SF-MPQ) and visual analog scale (VAS), disability measured with Roland Morris Questionnaire, and fear-avoidance beliefs measured with Fear-Avoidance Beliefs Questionnaire. Subjects receiving MFR displayed significant improvements in pain (SF-MPQ) (mean difference -7.8; 95% confidence interval [CI]: -14.5 to -1.1, P = 0.023) and sensory SF-MPQ subscale (mean difference -6.1; 95% CI: -10.8 to -1.5, P = 0.011) compared to the sham group, but no differences were found in VAS between groups. Disability and the Fear-Avoidance Beliefs Questionnaire score also displayed a significant decrease in the MFR group (P < 0.05) as compared to sham MFR. MFR therapy produced a significant improvement in both pain and disability. Because the minimal clinically important differences in pain and disability are, however, included in the 95% CI, we cannot know whether this improvement is clinically relevant. 2.
Lenihan, Catherine; Rogers, Caroline; Metcalfe, Anthony D; Martin, Yella H
2014-12-01
The use of cultured epithelial keratinocytes in the treatment of burns and skin graft donor sites is well established in clinical practice. The most widely used culture method for clinical use was originally developed by Rheinwald and Green 40 years ago. This system uses irradiated mouse dermal fibroblasts as a feeder cell layer to promote keratinocyte growth, a process that is costly and labor-intensive for health care providers. The medium formulation contains several components of animal origin, which pose further safety risks for patients. Improvements and simplification in the culturing process would lead to clear advantages: improved safety through reduction of xenobiotic components and reduction in cost for health care providers by dispensing with feeder cells. We compared the Rheinwald and Green method to culture in three commercially available, feeder-free media systems with defined/absent components of animal origin. During the isolation process, short incubation times in high-strength trypsin resulted in increased numbers of liberated keratinocyte stem cells compared with longer incubation times. All three commercially available media tested in this study could support the expansion of keratinocytes, with phenotypes comparable to cells expanded using the established Rheinwald and Green method. Growth rates varied, with two of the media displaying comparable growth rates, whereas the third was significantly slower. Our study demonstrates the suitability of such feeder-free media systems in clinical use. It further outlines a range of techniques to evaluate keratinocyte phenotype when assessing the suitability of cells for clinical application. Copyright © 2014 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.
Improved Protocols for Illumina Sequencing
Bronner, Iraad F.; Quail, Michael A.; Turner, Daniel J.; Swerdlow, Harold
2013-01-01
In this unit, we describe a set of improvements we have made to the standard Illumina protocols to make the sequencing process more reliable in a high-throughput environment, reduce amplification bias, narrow the distribution of insert sizes, and reliably obtain high yields of data. PMID:19582764
Balliana, Eleonora; Aramendía, Maite; Resano, Martin; Barbante, Carlo; Vanhaecke, Frank
2013-03-01
Although in many cases Pb isotopic analysis can be relied on for provenance determination of ancient bronzes, sometimes the use of "non-traditional" isotopic systems, such as those of Cu and Sn, is required. The work reported on in this paper aimed at revising the methodology for Cu and Sn isotope ratio measurements in archaeological bronzes via optimization of the analytical procedures in terms of sample pre-treatment, measurement protocol, precision, and analytical uncertainty. For Cu isotopic analysis, both Zn and Ni were investigated for their merit as internal standard (IS) relied on for mass bias correction. The use of Ni as IS seems to be the most robust approach as Ni is less prone to contamination, has a lower abundance in bronzes and an ionization potential similar to that of Cu, and provides slightly better reproducibility values when applied to NIST SRM 976 Cu isotopic reference material. The possibility of carrying out direct isotopic analysis without prior Cu isolation (with AG-MP-1 anion exchange resin) was investigated by analysis of CRM IARM 91D bronze reference material, synthetic solutions, and archaeological bronzes. Both procedures (Cu isolation/no Cu isolation) provide similar δ (65)Cu results with similar uncertainty budgets in all cases (±0.02-0.04 per mil in delta units, k = 2, n = 4). Direct isotopic analysis of Cu therefore seems feasible, without evidence of spectral interference or matrix-induced effect on the extent of mass bias. For Sn, a separation protocol relying on TRU-Spec anion exchange resin was optimized, providing a recovery close to 100 % without on-column fractionation. Cu was recovered quantitatively together with the bronze matrix with this isolation protocol. Isotopic analysis of this Cu fraction provides δ (65)Cu results similar to those obtained upon isolation using AG-MP-1 resin. This means that Cu and Sn isotopic analysis of bronze alloys can therefore be carried out after a single chromatographic separation using TRU-Spec resin. Tin isotopic analysis was performed relying on Sb as an internal standard used for mass bias correction. The reproducibility over a period of 1 month (n = 42) for the mass bias-corrected Sn isotope ratios is in the range of 0.06-0.16 per mil (2 s), for all the ratios monitored.
Nair, Bala G; Grunzweig, Katherine; Peterson, Gene N; Horibe, Mayumi; Neradilek, Moni B; Newman, Shu-Fang; Van Norman, Gail; Schwid, Howard A; Hao, Wei; Hirsch, Irl B; Patchen Dellinger, E
2016-06-01
Poor perioperative glycemic management can lead to negative surgical outcome. Improved compliance to glucose control protocol could lead to better glucose management. An Anesthesia Information Management System based decision support system-Smart Anesthesia Manager™ (SAM) was used to generate real-time reminders to the anesthesia providers to closely adhere to our institutional glucose management protocol. Compliance to hourly glucose measurements and correct insulin dose adjustments was compared for the baseline period (12 months) without SAM and the intervention period (12 months) with SAM decision support. Additionally, glucose management parameters were compared for the baseline and intervention periods. A total of 1587 cases during baseline and 1997 cases during intervention met the criteria for glucose management (diabetic patients or non-diabetic patients with glucose level >140 mg/dL). Among the intervention cases anesthesia providers chose to use SAM reminders 48.7 % of the time primarily for patients who had diabetes, higher HbA1C or body mass index, while disabling the system for the remaining cases. Compliance to hourly glucose measurement and correct insulin doses increased significantly during the intervention period when compared with the baseline (from 52.6 to 71.2 % and from 13.5 to 24.4 %, respectively). In spite of improved compliance to institutional protocol, the mean glucose levels and other glycemic management parameters did not show significant improvement with SAM reminders. Real-time electronic reminders improved intraoperative compliance to institutional glucose management protocol though glycemic parameters did not improve even when there was greater compliance to the protocol.
Shuel, Michelle L; Karlowsky, Kathleen E; Law, Dennis K S; Tsang, Raymond S W
2011-12-01
Population biology of Haemophilus influenzae can be studied by multilocus sequence typing (MLST), and isolates are assigned sequence types (STs) based on nucleotide sequence variations in seven housekeeping genes, including fucK. However, the ST cannot be assigned if one of the housekeeping genes is absent or cannot be detected by the current protocol. Occasionally, strains of H. influenzae have been reported to lack the fucK gene. In this study, we examined the prevalence of this mutation among our collection of H. influenzae isolates. Of the 704 isolates studied, including 282 encapsulated and 422 nonencapsulated isolates, nine were not typeable by MLST owing to failure to detect the fucK gene. All nine fucK-negative isolates were nonencapsulated and belonged to various biotypes. DNA sequencing of the fucose operon region confirmed complete deletion of genes in the operon in seven of the nine isolates, while in the remaining two isolates, some of the genes were found intact or in parts. The significance of these findings is discussed.
Column chromatography as a useful step in purification of diatom pigments.
Tokarek, Wiktor; Listwan, Stanisław; Pagacz, Joanna; Leśniak, Piotr; Latowski, Dariusz
2016-01-01
Fucoxanthin, diadinoxanthin and diatoxanthin are carotenoids found in brown algae and most other heterokonts. These pigments are involved in photosynthetic and photoprotective reactions, and they have many potential health benefits. They can be extracted from diatom Phaeodactylum tricornutum by sonication, extraction with chloroform : methanol and preparative thin layer chromatography. We assessed the utility of an additional column chromatography step in purification of these pigments. This novel addition to the isolation protocol increased the purity of fucoxanthin and allowed for concentration of diadinoxanthin and diatoxanthin before HPLC separation. The enhanced protocol is useful for obtaining high purity pigments for biochemical studies.
Caron, Alexandra G M; Thomas, Colette R; Berry, Kathryn L E; Motti, Cherie A; Ariel, Ellen; Brodie, Jon E
2018-02-01
Ocean contamination by plastics is a global issue. Although ingestion of plastic debris by sea turtles has been widely documented, contamination by microplastics (<5mm) is poorly known and likely to be under-reported. We developed a microplastic extraction protocol for examining green turtle (Chelonia mydas) chyme, which is multifarious in nature, by modifying and combining pre-established methods used to separate microplastics from organic matter and sediments. This protocol consists of visual inspection, nitric acid digestion, emulsification of residual fat, density separation, and chemical identification by Fourier transform infrared spectroscopy. This protocol enables the extraction of polyethylene, high-density polyethylene, (aminoethyl) polystyrene, polypropylene, and polyvinyl chloride microplastics >100μm. Two macroplastics and seven microplastics (two plastic paint chips and five synthetic fabric particles) were isolated from subsamples of two green turtles. Our results highlight the need for more research towards understanding the impact of microplastics on these threatened marine reptiles. Copyright © 2018 Elsevier Ltd. All rights reserved.
Fully device-independent quantum key distribution.
Vazirani, Umesh; Vidick, Thomas
2014-10-03
Quantum cryptography promises levels of security that are impossible to replicate in a classical world. Can this security be guaranteed even when the quantum devices on which the protocol relies are untrusted? This central question dates back to the early 1990s when the challenge of achieving device-independent quantum key distribution was first formulated. We answer this challenge by rigorously proving the device-independent security of a slight variant of Ekert's original entanglement-based protocol against the most general (coherent) attacks. The resulting protocol is robust: While assuming only that the devices can be modeled by the laws of quantum mechanics and are spatially isolated from each other and from any adversary's laboratory, it achieves a linear key rate and tolerates a constant noise rate in the devices. In particular, the devices may have quantum memory and share arbitrary quantum correlations with the eavesdropper. The proof of security is based on a new quantitative understanding of the monogamous nature of quantum correlations in the context of a multiparty protocol.
Fully Device-Independent Quantum Key Distribution
NASA Astrophysics Data System (ADS)
Vazirani, Umesh; Vidick, Thomas
2014-10-01
Quantum cryptography promises levels of security that are impossible to replicate in a classical world. Can this security be guaranteed even when the quantum devices on which the protocol relies are untrusted? This central question dates back to the early 1990s when the challenge of achieving device-independent quantum key distribution was first formulated. We answer this challenge by rigorously proving the device-independent security of a slight variant of Ekert's original entanglement-based protocol against the most general (coherent) attacks. The resulting protocol is robust: While assuming only that the devices can be modeled by the laws of quantum mechanics and are spatially isolated from each other and from any adversary's laboratory, it achieves a linear key rate and tolerates a constant noise rate in the devices. In particular, the devices may have quantum memory and share arbitrary quantum correlations with the eavesdropper. The proof of security is based on a new quantitative understanding of the monogamous nature of quantum correlations in the context of a multiparty protocol.
75 FR 36313 - Drawbridge Operation Regulation; Arkansas Waterway, Pine Bluff, AR
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-25
... remote drawbridge operator then establishes normal verbal radio communications. This protocol is used to isolate and differentiate these radio communications from the railroad communications that the remote... provide a reason for each suggestion or recommendation. You may submit your comments and material online...
Symbiodinium isolation by NaOH treatment.
Zamoum, Thamilla; Furla, Paola
2012-11-15
The presence of photosynthetic zooxanthellae (dinoflagellates) in the tissue of many cnidarians is the main reason for their ecological success (i.e. coral reefs). It could also be the main cause of their demise, as the worldwide bleaching of reef-building coral is nothing less than the breakdown of this symbiotic association. The stability of this relationship is the principal marker for the biomonitoring of cnidarian health. We have therefore developed a new, simple method to isolate zooxanthellae in a few steps using NaOH solution. The protocol was validated in three symbiotic cnidarian species: a sea anemone, a gorgonian and a coral. Our method allows the isolation of intact and viable zooxanthellae with better yields than classic methods, especially for species with a calcareous skeleton. Moreover, the isolated zooxanthellae were free of host nucleic contaminants, facilitating subsequent specific molecular analyses.
Lister, Michelle; Stevenson, Emma; Heeg, Daniela; Minton, Nigel P; Kuehne, Sarah A
2014-08-01
Effective isolation of Clostridium difficile from stool samples is important in the research setting, especially where low numbers of spores/vegetative cells may be present within a sample. In this study, three protocols for stool culture were investigated to find a sensitive, cost effective and timely method of C. difficile isolation. For the initial enrichment step, the effectiveness of two different rich media, cycloserine-cefoxitin fructose broth (CCFB) and cycloserine-cefoxitin mannitol broth with taurocholate and lysozyme (CCMB-TAL) were compared. For the comparison of four different, selective solid media; Cycloserine-cefoxitin fructose agar (CCFA), Cycloserine-cefoxitin egg yolk agar (CCEY), ChromID C. difficile and tryptone soy agar (TSA) with 5% sheep's blood with and without preceding broth enrichment were used. As a means to enable differentiation between C. difficile and other fecal flora, the effectiveness of the inclusion of a pH indictor (1% Neutral Red), was also evaluated. The data derived indicated that CCFB is more sensitive than CCMB-TAL, however, the latter had an improved recovery rate. A broth enrichment step had a reduced sensitivity over direct plating. ChromID C. difficile showed the best recovery rate whereas CCEY egg yolk agar was the most sensitive of the four. The addition of 1% Neutral Red did not show sufficient colour change when added to CCEY egg yolk agar to be used as a differential medium. For a low cost, timely and sensitive method of isolating C. difficile from stool samples we recommend direct plating onto CCEY egg yolk agar after heat shock. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.
Spackman, Erica; Cardona, Carol; Muñoz-Aguayo, Jeannette; Fleming, Susan
2016-01-01
The US National institutes of Health-Centers of Excellence for Influenza Research and Surveillance is a research consortium that funds numerous labs worldwide to conduct influenza A surveillance in diverse animal species. There is no harmonization of testing procedures among these labs; therefore an external quality assurance (EQA) program was implemented to evaluate testing accuracy among labs in the program in 2012. Accurate detection of novel influenza A variants is crucial because of the broad host range and potentially high virulence of the virus in diverse species. Two molecular detection sample sets and 2 serology sample sets (one with avian origin isolates, and one with mammalian origin isolates each) were made available at approximately six month intervals. Participating labs tested the material in accordance with their own protocols. During a five year period a total of 41 labs from 23 countries ordered a total of 132 avian molecular, 121 mammalian molecular and 90 serology sample sets. Testing was completed by 111 individuals. Detection of type A influenza by RT-PCR was reliable with a pass rate (80% or greater agreement with expected results) of 86.6% for avian and 86.2% for mammalian origin isolates. However, identification of subtype by RT-PCR was relatively poor with 54.1% and 75.9% accuracy for avian and mammalian influenza isolates respectively. Serological testing had an overall pass rate of 86.9% and 22/23 labs used commercial ELISA kits. Based on the results of this EQA program six labs modified their procedures to improve accuracy and one lab identified an unknown equipment problem. These data represent the successful implementation of an international EQA program for an infectious disease; insights into the logistics and test design are also discussed. PMID:27788155
Spackman, Erica; Cardona, Carol; Muñoz-Aguayo, Jeannette; Fleming, Susan
2016-01-01
The US National institutes of Health-Centers of Excellence for Influenza Research and Surveillance is a research consortium that funds numerous labs worldwide to conduct influenza A surveillance in diverse animal species. There is no harmonization of testing procedures among these labs; therefore an external quality assurance (EQA) program was implemented to evaluate testing accuracy among labs in the program in 2012. Accurate detection of novel influenza A variants is crucial because of the broad host range and potentially high virulence of the virus in diverse species. Two molecular detection sample sets and 2 serology sample sets (one with avian origin isolates, and one with mammalian origin isolates each) were made available at approximately six month intervals. Participating labs tested the material in accordance with their own protocols. During a five year period a total of 41 labs from 23 countries ordered a total of 132 avian molecular, 121 mammalian molecular and 90 serology sample sets. Testing was completed by 111 individuals. Detection of type A influenza by RT-PCR was reliable with a pass rate (80% or greater agreement with expected results) of 86.6% for avian and 86.2% for mammalian origin isolates. However, identification of subtype by RT-PCR was relatively poor with 54.1% and 75.9% accuracy for avian and mammalian influenza isolates respectively. Serological testing had an overall pass rate of 86.9% and 22/23 labs used commercial ELISA kits. Based on the results of this EQA program six labs modified their procedures to improve accuracy and one lab identified an unknown equipment problem. These data represent the successful implementation of an international EQA program for an infectious disease; insights into the logistics and test design are also discussed.
Probable nosocomial transmission of listeriosis in neonates.
Lazarus, C; Leclercq, A; Lecuit, M; Vaillant, V; Coignard, B; Blanchard, H; Novakova, I; Astagneau, P
2013-10-01
Listeria monocytogenes was isolated in two neonates born consecutively in the same hospital in France. The isolates had indistinguishable pulsed-field electrophoresis profiles. Retrospective epidemiological investigations found no evidence of a food-borne or environmental source. Infection control protocols and decontamination processes were in accordance with standard recommendations. The timing of onset of these infections within the same maternity unit, and the similarity of pulsed-field gel electrophoresis profiles suggests cross-infection of L. monocytogenes between the two neonates. Copyright © 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.
Differential staining of bacteria: gram stain.
Moyes, Rita B; Reynolds, Jackie; Breakwell, Donald P
2009-11-01
In 1884, Hans Christian Gram, a Danish doctor, developed a differential staining technique that is still the cornerstone of bacterial identification and taxonomic division. This multistep, sequential staining protocol separates bacteria into four groups based on cell morphology and cell wall structure: Gram-positive cocci, Gram-negative cocci, Gram-positive rods, and Gram-negative rods. The Gram stain is useful for assessing bacterial contamination of tissue culture samples or for examining the Gram stain status and morphological features of bacteria isolated from mixed or isolated bacterial cultures. (c) 2009 by John Wiley & Sons, Inc.
Electron microscope detection of an endogenous infection of retrovirus-like particles in L20B cells.
Roberts, Jason A; Thorley, Bruce R; Bruggink, Leesa D; Marshall, John A
2013-08-01
L20B cells are a cell line commonly used for the isolation of poliovirus. The current study indicates that L20B cells are chronically infected with a retrovirus-like particle that replicates in the cytoplasm and buds through the plasma membrane. The findings indicate that care is needed in the use of L20B cells for certain virus isolation studies and emphasize the importance of electron microscope studies as an adjunct to the development of diagnostic virology protocols.
Gans, Jonathan; Osborne, Jonathan; Cheng, Juliet; Djapgne, Louise; Oglesby-Sherrouse, Amanda G
2018-01-01
Bacterial small RNA molecules (sRNAs) are increasingly recognized as central regulators of bacterial stress responses and pathogenesis. In many cases, RNA-binding proteins are critical for the stability and function of sRNAs. Previous studies have adopted strategies to genetically tag an sRNA of interest, allowing isolation of RNA-protein complexes from cells. Here we present a sequence-specific affinity purification protocol that requires no prior genetic manipulation of bacterial cells, allowing isolation of RNA-binding proteins bound to native RNA molecules.
Functionalized alkoxy arene diazonium salts from paracetamol.
Schmidt, Bernd; Berger, René; Hölter, Frank
2010-03-21
Arene diazonium tetrafluoroborates can be synthesized from aromatic acetamides via a sequence of deacetylation, diazotation and precipitation, induced by anion exchange. The reaction is conducted as a convenient one-flask transformation with consecutive addition of the appropriate reagents. Exchange of solvents or removal of byproducts prior to isolation of the product is not required. The arene diazonium salts are isolated from the reaction mixture by simple filtration. Two complementary protocols are presented, and the utility of the reaction is exemplified for a synthesis of the diarylheptanoid natural product de-O-methyl centrolobine.
Goldberg, Andrew J; Zaidi, Razi; Brooking, Deirdre; Kim, Louise; Korda, Michelle; Masci, Lorenzo; Green, Ruth; O’Donnell, Paul; Smith, Roger
2018-01-01
Introduction Achilles tendinopathy (AT) is a cause of pain and disability affecting both athletes and sedentary individuals. More than 150 000 people in the UK every year suffer from AT. While there is much preclinical work on the use of stem cells in tendon pathology, there is a scarcity of clinical data looking at the use of mesenchymal stem cells to treat tendon disease and there does not appear to be any studies of the use of autologous cultured mesenchymal stem cells (MSCs) for AT. Our hypothesis is that autologous culture expanded MSCs implanted into an area of mid-portion AT will lead to improved pain-free mechanical function. The current paper presents the protocol for a phase IIa clinical study. Methods and analysis The presented protocol is for a non-commercial, single-arm, open-label, phase IIa proof-of-concept study. The study will recruit 10 participants and will follow them up for 6 months. Included will be patients aged 18–70 years with chronic mid-portion AT who have failed at least 6 months of non-operative management. Participants will have a bone marrow aspirate collected from the posterior iliac crest under either local or general anaesthetic. MSCs will be isolated and expanded from the bone marrow. Four to 6 weeks after the harvest, participants will undergo implantation of the culture expanded MSCs under local anaesthetic and ultrasound guidance. The primary outcome will be safety as defined by the incidence rate of serious adverse reaction. The secondary outcomes will be efficacy as measured by patient-reported outcome measures and radiological outcome using ultrasound techniques. Ethics and dissemination The protocol has been approved by the National Research Ethics Service Committee (London, Harrow; reference 13/LO/1670). Trial findings will be disseminated through peer-reviewed publications and conference presentations. Trial registration number NCT02064062. PMID:29764889
Beato, Marco; Bianchi, Mattia; Coratella, Giuseppe; Merlini, Michele; Drust, Barry
2018-02-01
Beato, M, Bianchi, M, Coratella, G, Merlini, M, and Drust, B. Effects of plyometric and directional training on speed and jump performance in elite youth soccer players. J Strength Cond Res 32(2): 289-296, 2018-Soccer players perform approximately 1,350 activities (every 4-6 seconds), such as accelerations/decelerations and changes of direction (CODs) during matches. It is well established that COD and plyometric training have a positive impact on fitness parameters in football players. This study analyzed the effect of a complex COD and plyometric protocol (CODJ-G) compared with an isolated COD protocol (COD-G) training on elite football players. A randomized pre-post parallel group trial was used in this study. Twenty-one youth players were enrolled in this study (mean ± SD; age 17 ± 0.8 years, mass 70.1 ± 6.4 kg, and height 177.4 ± 6.2 cm). Players were randomized into 2 different groups: CODJ-G (n = 11) and COD-G (n = 10), training frequency of 2 times a week more than 6 weeks. Sprint 10, 30, and 40 m, long jump, triple hop jump, and 505 COD test were considered. Exercise-induced within-group changes in performance for both CODJ-G and COD-G: long jump (effect size [ES] = 0.32 and ES = 0.26, respectively) and sprint 10 m (ES = -0.51 and ES = -0.22, respectively), after 6 weeks of training. Moreover, CODJ-G reported substantially better results (between-group changes) in long jump test (ES = 0.32). In conclusion, this study showed that short-term protocols (CODJ-G and COD-G) are important and able to give meaningful improvements on power and speed parameters in a specific soccer population. CODJ-G showed a larger effect in sprint and jump parameters compared with COD-G after the training protocol. This study offers important implications for designing COD and jumps training in elite soccer.
Kvitt, H; Ucko, M; Colorni, A; Batargias, C; Zlotkin, A; Knibb, W
2002-04-05
A PCR protocol for the rapid diagnosis of fish 'pasteurellosis' based on 16S rRNA gene sequences was developed. The procedure combines low annealing temperature that detects low titers of Photobacterium damselae but also related species, and high annealing temperature for the specific identification of P. damselae directly from infected fish. The PCR protocol was validated on 19 piscine isolates of P. damselae ssp. piscicida from different geographic regions (Japan, Italy, Spain, Greece and Israel), on spontaneously infected sea bream Sparus aurata and sea bass Dicentrarchus labrax, and on closely related American Type Culture Collection (ATCC) reference strains. PCR using high annealing temperature (64 degrees C) discriminated between P. damselae and closely related reference strains, including P. histaminum. Sixteen isolates of P. damselae ssp. piscicida, 2 P. damselae ssp. piscicida reference strains and 1 P. damselae ssp. damselae reference strain were subjected to Amplified Fragment Length Polymorphism (AFLP) analysis, and a similarity matrix was produced. Accordingly, the Japanese isolates of P. damselae ssp. piscicida were distinguished from the Mediterranean/European isolates at a cut-off value of 83% similarity. A further subclustering at a cut-off value of 97% allowed discrimination between the Israeli P. damselae ssp. piscicida isolates and the other Mediterranean/European isolates. The combination of PCR direct amplification and AFLP provides a 2-step procedure, where P. damselae is rapidly identified at genus level on the basis of its 16S rRNA gene sequence and then grouped into distinct clusters on the basis of AFLP polymorphisms. The first step of direct amplification is highly sensitive and has immediate practical consequences, offering fish farmers a rapid diagnosis, while the AFLP is more specific and detects intraspecific variation which, in our study, also reflected geographic correspondence. Because of its superior discriminative properties, AFLP can be an important tool for epidemiological and taxonomic studies of this highly homogeneous genus.
Isolating LacZ-expressing cells from mouse inner ear tissues using flow cytometry.
Jan, Taha A; Chai, Renjie; Sayyid, Zahra N; Cheng, Alan G
2011-12-23
Isolation of specific cell types allows one to analyze rare cell populations such as stem/progenitor cells. Such an approach to studying inner ear tissues presents a unique challenge because of the paucity of cells of interest and few transgenic reporter mouse models. Here, we describe a protocol using fluorescence-conjugated probes to selectively label LacZ-positive cells from the neonatal cochleae. The most common underlying pathology of sensorineural hearing loss is the irreversible damage and loss of cochlear sensory hair cells, which are required to transduce sound waves to neural impulses. Recent evidence suggests that the murine auditory and vestibular organs harbor stem/progenitor cells that may have regenerative potential. These findings warrant further investigation, including identifying specific cell types with stem/progenitor cell characteristics. The Wnt signaling pathway has been demonstrated to play a critical role in maintaining stem/progenitor cell populations in several organ systems. We have recently identified Wnt-responsive Axin2-expressing cells in the neonatal cochlea, but their function is largely unknown. To better understand the behavior of these Wnt-responsive cells in vitro, we have developed a method of isolating Axin2-expressing cells from cochleae of Axin2-LacZ reporter mice. Using flow cytometry to isolate Axin2-LacZ positive cells from the neonatal cochleae, we could in turn execute a variety of experiments on live cells to interrogate their behavior as stem/progenitor cells. Here, we describe in detail the steps for the microdissection of neonatal cochlea, dissociation of these tissues, labeling of the LacZ-positive cells using a fluorogenic substrate, and cell sorting. Techniques for dissociating cochleae into single cells and isolating cochlear cells via flow cytometry have been described. We have made modifications to these techniques to establish a novel protocol to isolate LacZ-expressing cells from the neonatal cochlea.
Axelrod, David M.; Chisti, Mohammod J.; Kache, Saraswati
2017-01-01
Background Pediatric sepsis has a high mortality rate in limited resource settings. Sepsis protocols have been shown to be a cost-effective strategy to improve morbidity and mortality in a variety of populations and settings. At Dhaka Hospital in Bangladesh, mortality from pediatric sepsis in high-risk children previously approached 60%, which prompted the implementation of an evidenced-based protocol in 2010. The clinical effectiveness of this protocol had not been measured. We hypothesized that implementation of a pediatric sepsis protocol improved clinical outcomes, including reducing mortality and length of hospital stay. Materials and methods This was a retrospective cohort study of children 1–59 months old with a diagnosis of sepsis, severe sepsis or septic shock admitted to Dhaka Hospital from 10/25/2009-10/25/2011. The primary outcome was inpatient mortality pre- and post-protocol implementation. Secondary outcomes included fluid overload, heart failure, respiratory insufficiency, length of hospital stay, and protocol compliance, as measured by antibiotic and fluid bolus administration within 60 minutes of hospital presentation. Results 404 patients were identified by a key-word search of the electronic medical record; 328 patients with a primary diagnosis of sepsis, severe sepsis, or septic shock were included (143 pre- and185 post-protocol) in the analysis. Pre- and post-protocol mortality were similar and not statistically significant (32.17% vs. 34.59%, p = 0.72). The adjusted odds ratio (AOR) for post-protocol mortality was 1.55 (95% CI, 0.88–2.71). The odds for developing fluid overload were significantly higher post-protocol (AOR 3.45, 95% CI, 2.04–5.85), as were the odds of developing heart failure (AOR 4.52, 95% CI, 1.43–14.29) and having a longer median length of stay (AOR 1.81, 95% CI 1.10–2.96). There was no statistically significant difference in respiratory insufficiency (pre- 65.7% vs. post- 70.3%, p = 0.4) or antibiotic administration between the cohorts (pre- 16.08% vs. post- 12.43%, p = 0.42). Conclusions Implementation of a pediatric sepsis protocol did not improve all-cause mortality or length of stay and may have been associated with increased fluid overload and heart failure during the study period in a large, non-governmental hospital in Bangladesh. Similar rates of early antibiotic administration may indicate poor protocol compliance. Though evidenced-based protocols are a potential cost-effective strategy to improve outcomes, future studies should focus on optimal implementation of context-relevant sepsis protocols in limited resource settings. PMID:28753618
Nanjareddy, Kalpana; Arthikala, Manoj-Kumar; Blanco, Lourdes; Arellano, Elizabeth S; Lara, Miguel
2016-06-24
Phaseolus vulgaris is one of the most extensively studied model legumes in the world. The P. vulgaris genome sequence is available; therefore, the need for an efficient and rapid transformation system is more imperative than ever. The functional characterization of P. vulgaris genes is impeded chiefly due to the non-amenable nature of Phaseolus sp. to stable genetic transformation. Transient transformation systems are convenient and versatile alternatives for rapid gene functional characterization studies. Hence, the present work focuses on standardizing methodologies for protoplast isolation from multiple tissues and transient transformation protocols for rapid gene expression analysis in the recalcitrant grain legume P. vulgaris. Herein, we provide methodologies for the high-throughput isolation of leaf mesophyll-, flower petal-, hypocotyl-, root- and nodule-derived protoplasts from P. vulgaris. The highly efficient polyethylene glycol-mannitol magnesium (PEG-MMG)-mediated transformation of leaf mesophyll protoplasts was optimized using a GUS reporter gene. We used the P. vulgaris SNF1-related protein kinase 1 (PvSnRK1) gene as proof of concept to demonstrate rapid gene functional analysis. An RT-qPCR analysis of protoplasts that had been transformed with PvSnRK1-RNAi and PvSnRK1-OE vectors showed the significant downregulation and ectopic constitutive expression (overexpression), respectively, of the PvSnRK1 transcript. We also demonstrated an improved transient transformation approach, sonication-assisted Agrobacterium-mediated transformation (SAAT), for the leaf disc infiltration of P. vulgaris. Interestingly, this method resulted in a 90 % transformation efficiency and transformed 60-85 % of the cells in a given area of the leaf surface. The constitutive expression of YFP further confirmed the amenability of the system to gene functional characterization studies. We present simple and efficient methodologies for protoplast isolation from multiple P. vulgaris tissues. We also provide a high-efficiency and amenable method for leaf mesophyll transformation for rapid gene functional characterization studies. Furthermore, a modified SAAT leaf disc infiltration approach aids in validating genes and their functions. Together, these methods help to rapidly unravel novel gene functions and are promising tools for P. vulgaris research.
Intraportal islet transplantation: the impact of the liver microenvironment.
Delaune, Vaihere; Berney, Thierry; Lacotte, Stéphanie; Toso, Christian
2017-03-01
The portal vein remains the preferred site for pancreatic islet transplantation due to its easy access and low morbidity. However, despite great progress in isolation and transplantation protocols over the past few years, it is still associated with the early loss of some 50-70% of transplanted islets. The complex liver microenvironment itself presumably plays an important role in this loss. The present review focuses on the specifics of the liver microenvironment, notably the localized hepatic ischemia/reperfusion injury following transplantation, the low oxygenation of the portal vein, the instant blood-mediated inflammatory reaction, the endogenous liver immune system, and the gut-liver axis, and how they can each have an impact on the transplanted islets. It identifies the potential, or already applied, clinical interventions for improving intraportal islet survival, and pinpoints those promising areas still lacking preclinical research. Future interventions on clinical intraportal islet transplantation need to take into account the global context of the liver microenvironment, with multi-point interventions being most likely to improve early islet survival and engraftment. © 2017 The Authors. Transplant International published by John Wiley & Sons Ltd on behalf of Steunstichting ESOT.
Yang, Lei; Chen, Shouming; Yang, Di; Li, Jiajin; Wu, Taixiang; Zuo, Yunxia
2018-01-01
Objective To learn about the overall quality of clinical anaesthesia study protocols from the Chinese Clinical Trials Registry and to discuss the way to improve study protocol quality. Methods We defined completeness of each sub-item in SPIRIT as N/A (not applicable) or with a score of 0, 1, or 2. For each protocol, we calculated the proportion of adequately reported items (score = 2 and N/A) and unreported items (score = 0). Protocol quality was determined according to the proportion of reported items, with values >50% indicating high quality. Protocol quality was determined according to the proportion of reported items. For each sub-item in SPIRIT, we calculated the adequately reported rate (percentage of all protocols with score 2 and NA on one sub-item) as well as the unreported rate (percentage of all protocols with score 0 on one sub-item). Results Total 126 study protocols were available for assessment. Among these, 88.1% were assessed as being of low quality. By comparison, the percentage of low-quality protocols was 88.9% after the publication of the SPIRIT statement. Among the 51 SPIRIT sub-items, 18 sub-items had an unreported rate above 90% while 16 had a higher adequately reported rate than an unreported rate. Conclusions The overall quality of clinical anaesthesia study protocols registered in the ChiCTR was poor. A mandatory protocol upload and self-check based on the SPIRIT statement during the trial registration process may improve protocol quality in the future. PMID:29872509