Virtual screening methods as tools for drug lead discovery from large chemical libraries.
Ma, X H; Zhu, F; Liu, X; Shi, Z; Zhang, J X; Yang, S Y; Wei, Y Q; Chen, Y Z
2012-01-01
Virtual screening methods have been developed and explored as useful tools for searching drug lead compounds from chemical libraries, including large libraries that have become publically available. In this review, we discussed the new developments in exploring virtual screening methods for enhanced performance in searching large chemical libraries, their applications in screening libraries of ~ 1 million or more compounds in the last five years, the difficulties in their applications, and the strategies for further improving these methods.
Yanagawa, T; Tokudome, S
1990-01-01
We developed methods to assess the cancer risks by screening tests. These methods estimate the size of the high risk group adjusted for the characteristics of screening tests and estimate the incidence rates of cancer among the high risk group adjusted for the characteristics of the tests. A method was also developed for selecting the cut-off point of a screening test. Finally, the methods were applied to estimate the risk of the adult T-cell leukemia/lymphoma. PMID:2269244
Nakamura, K; Naruse, I; Takizawa, Y
1999-09-01
A simplified mass screening method for methylmercury exposure was developed using methylmercury-volatilizing bacteria from Minamata Bay. Some bacteria can transform methylmercury into mercury vapor. Most mercury in the hair is methylmercury, which is readily extracted with HCl solution. Black spots are formed on X-ray film due to the reduction of Ag(+) emulsion with mercury vapor produced by methylmercury-volatilizing bacteria. By exploiting these characteristics, a screening method was developed, whereby the fur of rats injected with methylmercury chloride formed clear black spots on X-ray film, whereas the fur of rats injected with saline did not. Subsequently, 50 human hair samples were examined using this mass screening method. The method identified people who had high mercury concentration, over 20 microg/g. A few thousand hair samples may be screened in a day using this method because it is rapid, simple, and economical. This method, therefore, enables screening of persons with methylmercury poisoning in mercury-polluted areas. Copyright 1999 Academic Press.
Gaudin, Valérie
2017-09-01
Screening methods are used as a first-line approach to detect the presence of antibiotic residues in food of animal origin. The validation process guarantees that the method is fit-for-purpose, suited to regulatory requirements, and provides evidence of its performance. This article is focused on intra-laboratory validation. The first step in validation is characterisation of performance, and the second step is the validation itself with regard to pre-established criteria. The validation approaches can be absolute (a single method) or relative (comparison of methods), overall (combination of several characteristics in one) or criterion-by-criterion. Various approaches to validation, in the form of regulations, guidelines or standards, are presented and discussed to draw conclusions on their potential application for different residue screening methods, and to determine whether or not they reach the same conclusions. The approach by comparison of methods is not suitable for screening methods for antibiotic residues. The overall approaches, such as probability of detection (POD) and accuracy profile, are increasingly used in other fields of application. They may be of interest for screening methods for antibiotic residues. Finally, the criterion-by-criterion approach (Decision 2002/657/EC and of European guideline for the validation of screening methods), usually applied to the screening methods for antibiotic residues, introduced a major characteristic and an improvement in the validation, i.e. the detection capability (CCβ). In conclusion, screening methods are constantly evolving, thanks to the development of new biosensors or liquid chromatography coupled to tandem-mass spectrometry (LC-MS/MS) methods. There have been clear changes in validation approaches these last 20 years. Continued progress is required and perspectives for future development of guidelines, regulations and standards for validation are presented here.
Development and evaluation of nursing user interface screens using multiple methods.
Hyun, Sookyung; Johnson, Stephen B; Stetson, Peter D; Bakken, Suzanne
2009-12-01
Building upon the foundation of the Structured Narrative Electronic Health Record (EHR) model, we applied theory-based (combined Technology Acceptance Model and Task-Technology Fit Model) and user-centered methods to explore nurses' perceptions of functional requirements for an electronic nursing documentation system, design user interface screens reflective of the nurses' perspectives, and assess nurses' perceptions of the usability of the prototype user interface screens. The methods resulted in user interface screens that were perceived to be easy to use, potentially useful, and well-matched to nursing documentation tasks associated with Nursing Admission Assessment, Blood Administration, and Nursing Discharge Summary. The methods applied in this research may serve as a guide for others wishing to implement user-centered processes to develop or extend EHR systems. In addition, some of the insights obtained in this study may be informative to the development of safe and efficient user interface screens for nursing document templates in EHRs.
2014-04-01
surrogate model generation is difficult for high -dimensional problems, due to the curse of dimensionality. Variable screening methods have been...a variable screening model was developed for the quasi-molecular treatment of ion-atom collision [16]. In engineering, a confidence interval of...for high -level radioactive waste [18]. Moreover, the design sensitivity method can be extended to the variable screening method because vital
Colorectal cancer development and advances in screening.
Simon, Karen
2016-01-01
Most colon tumors develop via a multistep process involving a series of histological, morphological, and genetic changes that accumulate over time. This has allowed for screening and detection of early-stage precancerous polyps before they become cancerous in individuals at average risk for colorectal cancer (CRC), which may lead to substantial decreases in the incidence of CRC. Despite the known benefits of early screening, CRC remains the second leading cause of cancer-related deaths in the United States. Hence, it is important for health care providers to have an understanding of the risk factors for CRC and various stages of disease development in order to recommend appropriate screening strategies. This article provides an overview of the histological/molecular changes that characterize the development of CRC. It describes the available CRC screening methods and their advantages and limitations and highlights the stages of CRC development in which each screening method is most effective.
Colorectal cancer development and advances in screening
Simon, Karen
2016-01-01
Most colon tumors develop via a multistep process involving a series of histological, morphological, and genetic changes that accumulate over time. This has allowed for screening and detection of early-stage precancerous polyps before they become cancerous in individuals at average risk for colorectal cancer (CRC), which may lead to substantial decreases in the incidence of CRC. Despite the known benefits of early screening, CRC remains the second leading cause of cancer-related deaths in the United States. Hence, it is important for health care providers to have an understanding of the risk factors for CRC and various stages of disease development in order to recommend appropriate screening strategies. This article provides an overview of the histological/molecular changes that characterize the development of CRC. It describes the available CRC screening methods and their advantages and limitations and highlights the stages of CRC development in which each screening method is most effective. PMID:27486317
A Triangulation Method for Identifying Hydrostratigraphic Locations of Well Screens
DOE Office of Scientific and Technical Information (OSTI.GOV)
Whiteside, T. S.
2015-01-31
A method to identify the hydrostratigraphic location of well screens was developed using triangulation with known locations. This method was applied to all of the monitor wells being used to develop the new GSA groundwater model. Results from this method are closely aligned with those from an alternate method which uses a mesh surface.
Improvement of screening methods for silicon planar semiconductor devices
NASA Technical Reports Server (NTRS)
Berger, W. M.
1972-01-01
The results of the program for the development of a more sensitive method for selecting silicon planar semiconductor devices for long life applications are reported. The manufacturing technologies (MOS and Bipolar) are discussed along with the screening procedures developed as a result of the tests and evaluations, and the effectiveness of the MOS and Bilayer screening procedures are evaluated.
Prenatal Cell-Free DNA Screening
Prenatal cell-free DNA screening Overview Prenatal cell-free DNA (cfDNA) screening, also known as noninvasive prenatal screening, is a method to screen ... in a developing baby. During prenatal cell-free DNA screening, DNA from the mother and fetus is ...
NASA Technical Reports Server (NTRS)
1984-01-01
Standardized methods are established for screening of JAN B microcircuits and JANTXV semiconductor components for space mission or other critical applications when JAN S devices are not available. General specifications are provided which outline the DPA (destructive physical analysis), environmental, electrical, and data requirements for screening of various component technologies. This standard was developed for Air Force Space Division, and is available for use by other DOD agencies, NASA, and space systems contractors for establishing common screening methods for electronic components.
Developmental neurotoxicity testing (DNT) is perceived by many stakeholders to be an area in critical need of alternative methods to current animal testing protocols and gUidelines. An immediate goal is to develop test methods that are capable of screening large numbers of chemic...
Bass, Sarah Bauerle; Gordon, Thomas F.; Ruzek, Sheryl Burt; Wolak, Caitlin; Ruggieri, Dominique; Mora, Gabriella; Rovito, Michael J.; Britto, Johnson; Parameswaran, Lalitha; Abedin, Zainab; Ward, Stephanie; Paranjape, Anuradha; Lin, Karen; Meyer, Brian; Pitts, Khaliah
2017-01-01
African Americans have higher colorectal cancer (CRC) mortality than White Americans and yet have lower rates of CRC screening. Increased screening aids in early detection and higher survival rates. Coupled with low literacy rates, the burden of CRC morbidity and mortality is exacerbated in this population, making it important to develop culturally and literacy appropriate aids to help low-literacy African Americans make informed decisions about CRC screening. This article outlines the development of a low-literacy computer touch-screen colonoscopy decision aid using an innovative marketing method called perceptual mapping and message vector modeling. This method was used to mathematically model key messages for the decision aid, which were then used to modify an existing CRC screening tutorial with different messages. The final tutorial was delivered through computer touch-screen technology to increase access and ease of use for participants. Testing showed users were not only more comfortable with the touch-screen technology but were also significantly more willing to have a colonoscopy compared with a “usual care group.” Results confirm the importance of including participants in planning and that the use of these innovative mapping and message design methods can lead to significant CRC screening attitude change. PMID:23132838
Eliciting women's cervical screening preferences: a mixed methods systematic review protocol.
Wood, Brianne; Van Katwyk, Susan Rogers; El-Khatib, Ziad; McFaul, Susan; Taljaard, Monica; Wright, Erica; Graham, Ian D; Little, Julian
2016-08-11
With the accumulation of evidence regarding potential harms of cancer screening in recent years, researchers, policy-makers, and the public are becoming more critical of population-based cancer screening. Consequently, a high-quality cancer screening program should consider individuals' values and preferences when determining recommendations. In cervical cancer screening, offering women autonomy is considered a "person-centered" approach to health care services; however, it may impact the effectiveness of the program should women choose to not participate. As part of a larger project to investigate women's cervical screening preferences and correlates of these preferences, this systematic review will capture quantitative and qualitative investigations of women's cervical screening preferences and the methods used to elicit them. This mixed methods synthesis will use a thematic analysis approach to synthesize qualitative, quantitative, and mixed methods evidence. This protocol describes the methods that will be used in this investigation. A search strategy has been developed with a health librarian and peer reviewed using PRESS. Based on this strategy, five databases and the gray literature will be searched for studies that meet the inclusion criteria. The quality of the included individual studies will be examined using the Mixed Methods Appraisal Tool. Three reviewers will extract data from the primary studies on the tools or instruments used to elicit women's preferences regarding cervical cancer screening, theoretical frameworks used, outcomes measured, the outstanding themes from quantitative and qualitative evidence, and the identified preferences for cervical cancer screening. We will describe the relationships between study results and the study population, "intervention" (e.g., tool or instrument), and context. We will follow the PRISMA reporting guideline. We will compare findings across studies and between study methods (e.g., qualitative versus quantitative study designs). The strength of the synthesized findings will be assessed using the validated GRADE and CERQual tool. This review will inform the development of a tool to elicit women's cervical screening preferences. Understanding the methods used to elicit women's preferences and what is known about women's cervical screening preferences will be useful for guideline developers who wish to incorporate a woman-centered approach specifically for cervical screening guidelines. PROSPERO CRD42016035737.
Noguchi, Akio; Nakamura, Kosuke; Sakata, Kozue; Sato-Fukuda, Nozomi; Ishigaki, Takumi; Mano, Junichi; Takabatake, Reona; Kitta, Kazumi; Teshima, Reiko; Kondo, Kazunari; Nishimaki-Mogami, Tomoko
2016-04-19
A number of genetically modified (GM) maize events have been developed and approved worldwide for commercial cultivation. A screening method is needed to monitor GM maize approved for commercialization in countries that mandate the labeling of foods containing a specified threshold level of GM crops. In Japan, a screening method has been implemented to monitor approved GM maize since 2001. However, the screening method currently used in Japan is time-consuming and requires generation of a calibration curve and experimental conversion factor (C(f)) value. We developed a simple screening method that avoids the need for a calibration curve and C(f) value. In this method, ΔC(q) values between the target sequences and the endogenous gene are calculated using multiplex real-time PCR, and the ΔΔC(q) value between the analytical and control samples is used as the criterion for determining analytical samples in which the GM organism content is below the threshold level for labeling of GM crops. An interlaboratory study indicated that the method is applicable independently with at least two models of PCR instruments used in this study.
High throughput screening of active pharmaceutical ingredients by UPLC.
Al-Sayah, Mohammad A; Rizos, Panagiota; Antonucci, Vincent; Wu, Naijun
2008-07-01
Ultra performance LC (UPLC) was evaluated as an efficient screening approach to facilitate method development for drug candidates. Three stationary phases were screened: C-18, phenyl, and Shield RP 18 with column dimensions of 150 mm x 2.1 mm, 1.7 microm, which should theoretically generate 35,000 plates or 175% of the typical column plate count of a conventional 250 mm x 4.6 mm, 5 microm particle column. Thirteen different active pharmaceutical ingredients (APIs) were screened using this column set with a standardized mobile-phase gradient. The UPLC method selectivity results were compared to those obtained for these compounds via methods developed through laborious trial and error screening experiments using numerous conventional HPLC mobile and stationary phases. Peak capacity was compared for columns packed with 5 microm particles and columns packed with 1.7 microm particles. The impurities screened by UPLC were confirmed by LC/MS. The results demonstrate that simple, high efficiency UPLC gradients are a feasible and productive alternative to more conventional multiparametric chromatographic screening approaches for many compounds in the early stages of drug development.
Gaudin, Valérie
2017-04-15
Antibiotic residues may be found in food of animal origin, since veterinary drugs are used for preventive and curative purposes to treat animals. The control of veterinary drug residues in food is necessary to ensure consumer safety. Screening methods are the first step in the control of antibiotic residues in food of animal origin. Conventional screening methods are based on different technologies, microbiological methods, immunological methods or physico-chemical methods (e.g. thin-layer chromatography, HPLC, LC-MS/MS). Screening methods should be simple, quick, inexpensive and specific, with low detection limits and high sample throughput. Biosensors can meet some of these requirements. Therefore, the development of biosensors for the screening of antibiotic residues has been increasing since the 1980s. The present review provides extensive and up-to-date findings on biosensors for the screening of antibiotic residues in food products of animal origin. Biosensors are constituted of a bioreceptor and a transducer. In the detection of antibiotic residues, even though antibodies were the first bioreceptors to be used, new kinds of bioreceptors are being developed more and more (enzymes, aptamers, MIPs); their advantages and drawbacks are discussed in this review. The different categories of transducers (electrochemical, mass-based biosensors, optical and thermal) and their potential applications for the screening of antibiotic residues in food are presented. Moreover, the advantages and drawbacks of the different types of transducers are discussed. Lastly, outlook and the future development of biosensors for the control of antibiotic residues in food are highlighted. Copyright © 2016. Published by Elsevier B.V.
Machine learning plus optical flow: a simple and sensitive method to detect cardioactive drugs
NASA Astrophysics Data System (ADS)
Lee, Eugene K.; Kurokawa, Yosuke K.; Tu, Robin; George, Steven C.; Khine, Michelle
2015-07-01
Current preclinical screening methods do not adequately detect cardiotoxicity. Using human induced pluripotent stem cell-derived cardiomyocytes (iPS-CMs), more physiologically relevant preclinical or patient-specific screening to detect potential cardiotoxic effects of drug candidates may be possible. However, one of the persistent challenges for developing a high-throughput drug screening platform using iPS-CMs is the need to develop a simple and reliable method to measure key electrophysiological and contractile parameters. To address this need, we have developed a platform that combines machine learning paired with brightfield optical flow as a simple and robust tool that can automate the detection of cardiomyocyte drug effects. Using three cardioactive drugs of different mechanisms, including those with primarily electrophysiological effects, we demonstrate the general applicability of this screening method to detect subtle changes in cardiomyocyte contraction. Requiring only brightfield images of cardiomyocyte contractions, we detect changes in cardiomyocyte contraction comparable to - and even superior to - fluorescence readouts. This automated method serves as a widely applicable screening tool to characterize the effects of drugs on cardiomyocyte function.
Chavez, Pierre-François; Meeus, Joke; Robin, Florent; Schubert, Martin Alexander; Somville, Pascal
2018-01-01
The evaluation of drug–polymer miscibility in the early phase of drug development is essential to ensure successful amorphous solid dispersion (ASD) manufacturing. This work investigates the comparison of thermodynamic models, conventional experimental screening methods (solvent casting, quench cooling), and a novel atomization screening device based on their ability to predict drug–polymer miscibility, solid state properties (Tg value and width), and adequate polymer selection during the development of spray-dried amorphous solid dispersions (SDASDs). Binary ASDs of four drugs and seven polymers were produced at 20:80, 40:60, 60:40, and 80:20 (w/w). Samples were systematically analyzed using modulated differential scanning calorimetry (mDSC) and X-ray powder diffraction (XRPD). Principal component analysis (PCA) was used to qualitatively assess the predictability of screening methods with regards to SDASD development. Poor correlation was found between theoretical models and experimentally-obtained results. Additionally, the limited ability of usual screening methods to predict the miscibility of SDASDs did not guarantee the appropriate selection of lead excipient for the manufacturing of robust SDASDs. Contrary to standard approaches, our novel screening device allowed the selection of optimal polymer and drug loading and established insight into the final properties and performance of SDASDs at an early stage, therefore enabling the optimization of the scaled-up late-stage development. PMID:29518936
High-throughput screening for bioactive components from traditional Chinese medicine.
Zhu, Yanhui; Zhang, Zhiyun; Zhang, Meng; Mais, Dale E; Wang, Ming-Wei
2010-12-01
Throughout the centuries, traditional Chinese medicine has been a rich resource in the development of new drugs. Modern drug discovery, which relies increasingly on automated high throughput screening and quick hit-to-lead development, however, is confronted with the challenges of the chemical complexity associated with natural products. New technologies for biological screening as well as library building are in great demand in order to meet the requirements. Here we review the developments in these techniques under the perspective of their applicability in natural product drug discovery. Methods in library building, component characterizing, biological evaluation, and other screening methods including NMR and X-ray diffraction are discussed.
Terbium-sensitized luminescence screening method for fluoroquinolones in beef serum
USDA-ARS?s Scientific Manuscript database
Enrofloxacin is one of only two fluoroquinolone antibiotics approved for use in cattle in the U.S. Microbial screening methods commonly used for monitoring veterinary drug residues are not sensitive or selective for fluoroquinolones. In this work, a luminescence-based screening assay was developed...
Experimental design methodologies in the optimization of chiral CE or CEC separations: an overview.
Dejaegher, Bieke; Mangelings, Debby; Vander Heyden, Yvan
2013-01-01
In this chapter, an overview of experimental designs to develop chiral capillary electrophoresis (CE) and capillary electrochromatographic (CEC) methods is presented. Method development is generally divided into technique selection, method optimization, and method validation. In the method optimization part, often two phases can be distinguished, i.e., a screening and an optimization phase. In method validation, the method is evaluated on its fit for purpose. A validation item, also applying experimental designs, is robustness testing. In the screening phase and in robustness testing, screening designs are applied. During the optimization phase, response surface designs are used. The different design types and their application steps are discussed in this chapter and illustrated by examples of chiral CE and CEC methods.
Xue, Xiaonan; Kim, Mimi Y; Castle, Philip E; Strickler, Howard D
2014-03-01
Studies to evaluate clinical screening tests often face the problem that the "gold standard" diagnostic approach is costly and/or invasive. It is therefore common to verify only a subset of negative screening tests using the gold standard method. However, undersampling the screen negatives can lead to substantial overestimation of the sensitivity and underestimation of the specificity of the diagnostic test. Our objective was to develop a simple and accurate statistical method to address this "verification bias." We developed a weighted generalized estimating equation approach to estimate, in a single model, the accuracy (eg, sensitivity/specificity) of multiple assays and simultaneously compare results between assays while addressing verification bias. This approach can be implemented using standard statistical software. Simulations were conducted to assess the proposed method. An example is provided using a cervical cancer screening trial that compared the accuracy of human papillomavirus and Pap tests, with histologic data as the gold standard. The proposed approach performed well in estimating and comparing the accuracy of multiple assays in the presence of verification bias. The proposed approach is an easy to apply and accurate method for addressing verification bias in studies of multiple screening methods. Copyright © 2014 Elsevier Inc. All rights reserved.
Evaluation of a standard test method for screening fuels in soils
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sorini, S.S.; Schabron, J.F.
1996-12-31
A new screening method for fuel contamination in soils was recently developed as American Society for Testing and Materials (ASTM) Method D-5831-95, Standard Test Method for Screening Fuels in Soils. This method uses low-toxicity chemicals and can be sued to screen organic- rich soils, as well as being fast, easy, and inexpensive to perform. Fuels containing aromatic compounds, such as diesel fuel and gasoline, as well as other aromatic-containing hydrocarbon materials, such as motor oil, crude oil, and cola oil, can be determined. The screening method for fuels in soils was evaluated by conducting a Collaborative study on the method.more » In the Collaborative study, a sand and an organic soil spiked with various concentrations of diesel fuel were tested. Data from the Collaborative study were used to determine the reproducibility (between participants) and repeatability (within participants) precision of the method for screening the test materials. The Collaborative study data also provide information on the performance of portable field equipment (patent pending) versus laboratory equipment for performing the screening method and a comparison of diesel concentration values determined using the screening method versus a laboratory method.« less
Woods, Lucy A; Dolezal, Olan; Ren, Bin; Ryan, John H; Peat, Thomas S; Poulsen, Sally-Ann
2016-03-10
Fragment-based drug discovery (FBDD) is contingent on the development of analytical methods to identify weak protein-fragment noncovalent interactions. Herein we have combined an underutilized fragment screening method, native state mass spectrometry, together with two proven and popular fragment screening methods, surface plasmon resonance and X-ray crystallography, in a fragment screening campaign against human carbonic anhydrase II (CA II). In an initial fragment screen against a 720-member fragment library (the "CSIRO Fragment Library") seven CA II binding fragments, including a selection of nonclassical CA II binding chemotypes, were identified. A further 70 compounds that comprised the initial hit chemotypes were subsequently sourced from the full CSIRO compound collection and screened. The fragment results were extremely well correlated across the three methods. Our findings demonstrate that there is a tremendous opportunity to apply native state mass spectrometry as a complementary fragment screening method to accelerate drug discovery.
Screening assessment methods have been developed for semi- and non-volatile persistent organic pollutants (POPs) for human blood and solid environmental media. The specific methodology is developed for measuring the presence of "native" compounds, specifically, a var...
NASA Astrophysics Data System (ADS)
Satoh, Hitoshi; Niki, Noboru; Mori, Kiyoshi; Eguchi, Kenji; Kaneko, Masahiro; Kakinuma, Ryutarou; Moriyama, Noriyuki; Ohmatsu, Hironobu; Masuda, Hideo; Machida, Suguru
2007-03-01
Multislice CT scanner advanced remarkably at the speed at which the chest CT images were acquired for mass screening. Mass screening based on multislice CT images requires a considerable number of images to be read. It is this time-consuming step that makes the use of helical CT for mass screening impractical at present. To overcome this problem, we have provided diagnostic assistance methods to medical screening specialists by developing a lung cancer screening algorithm that automatically detects suspected lung cancers in helical CT images and a coronary artery calcification screening algorithm that automatically detects suspected coronary artery calcification. Moreover, we have provided diagnostic assistance methods to medical screening specialists by using a lung cancer screening algorithm built into mobile helical CT scanner for the lung cancer mass screening done in the region without the hospital. We also have developed electronic medical recording system and prototype internet system for the community health in two or more regions by using the Virtual Private Network router and Biometric fingerprint authentication system and Biometric face authentication system for safety of medical information. Based on these diagnostic assistance methods, we have now developed a new computer-aided workstation and database that can display suspected lesions three-dimensionally in a short time. This paper describes basic studies that have been conducted to evaluate this new system.
Experimental cocrystal screening and solution based scale-up cocrystallization methods.
Malamatari, Maria; Ross, Steven A; Douroumis, Dennis; Velaga, Sitaram P
2017-08-01
Cocrystals are crystalline single phase materials composed of two or more different molecular and/or ionic compounds generally in a stoichiometric ratio which are neither solvates nor simple salts. If one of the components is an active pharmaceutical ingredient (API), the term pharmaceutical cocrystal is often used. There is a growing interest among drug development scientists in exploring cocrystals, as means to address physicochemical, biopharmaceutical and mechanical properties and expand solid form diversity of the API. Conventionally, coformers are selected based on crystal engineering principles, and the equimolar mixtures of API and coformers are subjected to solution-based crystallization that are commonly employed in polymorph and salt screening. However, the availability of new knowledge on cocrystal phase behaviour in solid state and solutions has spurred the development and implementation of more rational experimental cocrystal screening as well as scale-up methods. This review aims to provide overview of commonly employed solid form screening techniques in drug development with an emphasis on cocrystal screening methodologies. The latest developments in understanding and the use of cocrystal phase diagrams in both screening and solution based scale-up methods are also presented. Final section is devoted to reviewing the state of the art research covering solution based scale-up cocrystallization process for different cocrystals besides more recent continuous crystallization methods. Copyright © 2017 Elsevier B.V. All rights reserved.
Liu, Rui-Sang; Jin, Guang-Huai; Xiao, Deng-Rong; Li, Hong-Mei; Bai, Feng-Wu; Tang, Ya-Jie
2015-01-01
Aroma results from the interplay of volatile organic compounds (VOCs) and the attributes of microbial-producing aromas are significantly affected by fermentation conditions. Among the VOCs, only a few of them contribute to aroma. Thus, screening and identification of the key VOCs is critical for microbial-producing aroma. The traditional method is based on gas chromatography-olfactometry (GC-O), which is time-consuming and laborious. Considering the Tuber melanosporum fermentation system as an example, a new method to screen and identify the key VOCs by combining the aroma evaluation method with principle component analysis (PCA) was developed in this work. First, an aroma sensory evaluation method was developed to screen 34 potential favorite aroma samples from 504 fermentation samples. Second, PCA was employed to screen nine common key VOCs from these 34 samples. Third, seven key VOCs were identified by the traditional method. Finally, all of the seven key VOCs identified by the traditional method were also identified, along with four others, by the new strategy. These results indicate the reliability of the new method and demonstrate it to be a viable alternative to the traditional method. PMID:26655663
Testing the Untestable: A Vision Screening Program for Exceptional Children.
ERIC Educational Resources Information Center
Bishop, Virginia E.; Godolphin, Vivienne
Based on a longitudinal study of vision screening techniques for handicapped children at the Chester County (Pennsylvania) Child Development Center, the paper reports on the development of a battery of effective vision screening methods for children with low functioning handicapped children. Specific tests are described, including the Sheridan…
to rapidly test /screen breast cancer therapeutics as a strategy to streamline drug development and provide individualized treatment. The results...system can therefore be used to streamline pre-clinical drug development, by reducing the number of animals , cost, and time required to screen new drugs
A Proven Method for Meeting Export Control Objectives in Postal and Shipping Sectors
2015-02-01
Mellon University for the operation of the Software Engineering Institute, a federally funded research and development center sponsored by the United...Export Control at USPS 5 3.3 Objectives for Improving Export Screening at USPS 6 4 Development of the New Screening Process 7 4.1 “Walking the Model...Export Screening Development Process 10 Figure 2: Induction and Processing of International Mail 10 Figure 3: The Export Screening Process 11
ERIC Educational Resources Information Center
Katz, Mira L.; Heaner, Sarah; Reiter, Paul; van Putten, Julie; Murray, Lee; McDougle, Leon; Cegala, Donald J.; Post, Douglas; David, Prabu; Slater, Michael; Paskett, Electra D.
2009-01-01
Background: Low rates of colorectal cancer (CRC) screening persist due to individual, provider, and system level barriers. Purpose: To develop and obtain initial feedback about a CRC screening educational video from community members and medical professionals. Methods: Focus groups of patients were conducted prior to the development of the CRC…
Animal welfare concerns and the high cost associated with in vivo chemical screening methods have prompted efforts to develop highly specific and sensitive in vitro techniques to evaluate chemicals for endocrine activity. Diagnostic biomarkers developed using in vitro methods sho...
Development and Initial Validation of the Symptoms and Assets Screening Scale
ERIC Educational Resources Information Center
Downs, Andrew; Boucher, Laura A.; Campbell, Duncan G.; Dasse, Michelle
2013-01-01
Objective: To develop and test a screening measure of mental health symptoms and well-being in college students, the Symptoms and Assets Screening Scale (SASS). Participants: Participants were 758 college students at 2 universities in the Northwest sampled between October 2009 and April 2011. Methods: Participants completed the SASS, as well as…
Shah, Sunny S.; Senapati, Satyajyoti; Klacsmann, Flora; Miller, Daniel L.; Johnson, Jeff J.; Chang, Hsueh-Chia; Stack, M. Sharon
2016-01-01
Mucosal infection by the human papillomavirus (HPV) is responsible for a growing number of malignancies, predominantly represented by cervical cancer and oropharyngeal squamous cell carcinoma. Because of the prevalence of the virus, persistence of infection, and long latency period, novel and low-cost methods are needed for effective population level screening and monitoring. We review established methods for screening of cervical and oral cancer as well as commercially-available techniques for detection of HPV DNA. We then describe the ongoing development of microfluidic nucleic acid-based biosensors to evaluate circulating host microRNAs that are produced in response to an oncogenic HPV infection. The goal is to develop an ideal screening platform that is low-cost, portable, and easy to use, with appropriate signal stability, sensitivity and specificity. Advances in technologies for sample lysis, pre-treatment and concentration, and multiplexed nucleic acid detection are provided. Continued development of these devices provides opportunities for cancer screening in low resource settings, for point-of-care diagnostics and self-screening, and for monitoring response to vaccination or surgical treatment. PMID:27618102
Novel method for screening of enteric film coatings properties with magnetic resonance imaging.
Dorożyński, Przemysław; Jamróz, Witold; Niwiński, Krzysztof; Kurek, Mateusz; Węglarz, Władysław P; Jachowicz, Renata; Kulinowski, Piotr
2013-11-18
The aim of the study is to present the concept of novel method for fast screening of enteric coating compositions properties without the need of preparation of tablets batches for fluid bed coating. Proposed method involves evaluation of enteric coated model tablets in specially designed testing cell with application of MRI technique. The results obtained in the testing cell were compared with results of dissolution studies of mini-tablets coated in fluid bed apparatus. The method could be useful in early stage of formulation development for screening of film coating properties that will shorten and simplify the development works. Copyright © 2013 Elsevier B.V. All rights reserved.
Knopf-Amelung, Sarah; Gotham, Heather; Kuofie, Araba; Young, Pamela; Manney Stinson, Ronalda; Lynn, Jolene; Barker, Kendra; Hildreth, Jessica
Most nursing programs lack curriculum on substance use. This project evaluated 3 didactic instructional methods for teaching baccalaureate nursing students about screening, brief intervention, and referral to treatment for substance use. In-person, asynchronous narrated slides and interactive online instructional methods were all effective in developing students' competency; however, active learning methods (in-person and interactive online course) were more effective in changing students' attitudes about their role in screening and intervening for drug use.
Takabatake, Reona; Onishi, Mari; Koiwa, Tomohiro; Futo, Satoshi; Minegishi, Yasutaka; Akiyama, Hiroshi; Teshima, Reiko; Kurashima, Takeyo; Mano, Junichi; Furui, Satoshi; Kitta, Kazumi
2013-01-01
A novel real-time polymerase chain reaction (PCR)-based quantitative screening method was developed for three genetically modified soybeans: RRS, A2704-12, and MON89788. The 35S promoter (P35S) of cauliflower mosaic virus is introduced into RRS and A2704-12 but not MON89788. We then designed a screening method comprised of the combination of the quantification of P35S and the event-specific quantification of MON89788. The conversion factor (Cf) required to convert the amount of a genetically modified organism (GMO) from a copy number ratio to a weight ratio was determined experimentally. The trueness and precision were evaluated as the bias and reproducibility of relative standard deviation (RSDR), respectively. The determined RSDR values for the method were less than 25% for both targets. We consider that the developed method would be suitable for the simple detection and approximate quantification of GMO.
A permutation-based non-parametric analysis of CRISPR screen data.
Jia, Gaoxiang; Wang, Xinlei; Xiao, Guanghua
2017-07-19
Clustered regularly-interspaced short palindromic repeats (CRISPR) screens are usually implemented in cultured cells to identify genes with critical functions. Although several methods have been developed or adapted to analyze CRISPR screening data, no single specific algorithm has gained popularity. Thus, rigorous procedures are needed to overcome the shortcomings of existing algorithms. We developed a Permutation-Based Non-Parametric Analysis (PBNPA) algorithm, which computes p-values at the gene level by permuting sgRNA labels, and thus it avoids restrictive distributional assumptions. Although PBNPA is designed to analyze CRISPR data, it can also be applied to analyze genetic screens implemented with siRNAs or shRNAs and drug screens. We compared the performance of PBNPA with competing methods on simulated data as well as on real data. PBNPA outperformed recent methods designed for CRISPR screen analysis, as well as methods used for analyzing other functional genomics screens, in terms of Receiver Operating Characteristics (ROC) curves and False Discovery Rate (FDR) control for simulated data under various settings. Remarkably, the PBNPA algorithm showed better consistency and FDR control on published real data as well. PBNPA yields more consistent and reliable results than its competitors, especially when the data quality is low. R package of PBNPA is available at: https://cran.r-project.org/web/packages/PBNPA/ .
Terakado, Shingo; Glass, Thomas R; Sasaki, Kazuhiro; Ohmura, Naoya
2014-01-01
A simple new model for estimating the screening performance (false positive and false negative rates) of a given test for a specific sample population is presented. The model is shown to give good results on a test population, and is used to estimate the performance on a sampled population. Using the model developed in conjunction with regulatory requirements and the relative costs of the confirmatory and screening tests allows evaluation of the screening test's utility in terms of cost savings. Testers can use the methods developed to estimate the utility of a screening program using available screening tests with their own sample populations.
Zhu, Xudong; Arman, Bessembayev; Chu, Ju; Wang, Yonghong; Zhuang, Yingping
2017-05-01
To develop an efficient cost-effective screening process to improve production of glucoamylase in Aspergillus niger. The cultivation of A. niger was achieved with well-dispersed morphology in 48-deep-well microtiter plates, which increased the throughput of the samples compared to traditional flask cultivation. There was a close negative correlation between glucoamylase and its pH of the fermentation broth. A novel high-throughput analysis method using Methyl Orange was developed. When compared to the conventional analysis method using 4-nitrophenyl α-D-glucopyranoside as substrate, a correlation coefficient of 0.96 by statistical analysis was obtained. Using this novel screening method, we acquired a strain with an activity of 2.2 × 10 3 U ml -1 , a 70% higher yield of glucoamylase than its parent strain.
Coformer screening using thermal analysis based on binary phase diagrams.
Yamashita, Hiroyuki; Hirakura, Yutaka; Yuda, Masamichi; Terada, Katsuhide
2014-08-01
The advent of cocrystals has demonstrated a growing need for efficient and comprehensive coformer screening in search of better development forms, including salt forms. Here, we investigated a coformer screening system for salts and cocrystals based on binary phase diagrams using thermal analysis and examined the effectiveness of the method. Indomethacin and tenoxicam were used as models of active pharmaceutical ingredients (APIs). Physical mixtures of an API and 42 kinds of coformers were analyzed using Differential Scanning Calorimetry (DSC) and X-ray DSC. We also conducted coformer screening using a conventional slurry method and compared these results with those from the thermal analysis method and previous studies. Compared with the slurry method, the thermal analysis method was a high-performance screening system, particularly for APIs with low solubility and/or propensity to form solvates. However, this method faced hurdles for screening coformers combined with an API in the presence of kinetic hindrance for salt or cocrystal formation during heating or if there is degradation near the metastable eutectic temperature. The thermal analysis and slurry methods are considered complementary to each other for coformer screening. Feasibility of the thermal analysis method in drug discovery practice is ensured given its small scale and high throughput.
NETL CO 2 Storage prospeCtive Resource Estimation Excel aNalysis (CO 2-SCREEN) User's Manual
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sanguinito, Sean M.; Goodman, Angela; Levine, Jonathan
This user’s manual guides the use of the National Energy Technology Laboratory’s (NETL) CO 2 Storage prospeCtive Resource Estimation Excel aNalysis (CO 2-SCREEN) tool, which was developed to aid users screening saline formations for prospective CO 2 storage resources. CO 2- SCREEN applies U.S. Department of Energy (DOE) methods and equations for estimating prospective CO 2 storage resources for saline formations. CO2-SCREEN was developed to be substantive and user-friendly. It also provides a consistent method for calculating prospective CO 2 storage resources that allows for consistent comparison of results between different research efforts, such as the Regional Carbon Sequestration Partnershipsmore » (RCSP). CO 2-SCREEN consists of an Excel spreadsheet containing geologic inputs and outputs, linked to a GoldSim Player model that calculates prospective CO 2 storage resources via Monte Carlo simulation.« less
Effect of Vibration on Retention Characteristics of Screen Acquisition Systems
NASA Technical Reports Server (NTRS)
Tegart, J. R.; Park, A. C.
1977-01-01
An analytical and experimental investigation of the effect of vibration on the retention characteristics of screen acquisition systems was performed. The functioning of surface tension devices using fine-mesh screens requires that the pressure differential acting on the screen be less than its pressure retention capability. When exceeded, screen breakdown will occur and gas-free expulsion of propellant will no longer be possible. An analytical approach to predicting the effect of vibration was developed. This approach considers the transmission of the vibration to the screens of the device and the coupling of the liquid and the screen in establishing the screen response. A method of evaluating the transient response of the gas/liquid interface within the screen was also developed.
Ye, Lidan; Yang, Chengcheng; Yu, Hongwei
2018-01-01
With increasing concerns in sustainable development, biocatalysis has been recognized as a competitive alternative to traditional chemical routes in the past decades. As nature's biocatalysts, enzymes are able to catalyze a broad range of chemical transformations, not only with mild reaction conditions but also with high activity and selectivity. However, the insufficient activity or enantioselectivity of natural enzymes toward non-natural substrates limits their industrial application, while directed evolution provides a potent solution to this problem, thanks to its independence on detailed knowledge about the relationship between sequence, structure, and mechanism/function of the enzymes. A proper high-throughput screening (HTS) method is the key to successful and efficient directed evolution. In recent years, huge varieties of HTS methods have been developed for rapid evaluation of mutant libraries, ranging from in vitro screening to in vivo selection, from indicator addition to multi-enzyme system construction, and from plate screening to computation- or machine-assisted screening. Recently, there is a tendency to integrate directed evolution with metabolic engineering in biosynthesis, using metabolites as HTS indicators, which implies that directed evolution has transformed from molecular engineering to process engineering. This paper aims to provide an overview of HTS methods categorized based on the reaction principles or types by summarizing related studies published in recent years including the work from our group, to discuss assay design strategies and typical examples of HTS methods, and to share our understanding on HTS method development for directed evolution of enzymes involved in specific catalytic reactions or metabolic pathways.
Dunn, Richard A; Tan, Andrew K G
2011-01-01
As is the case in many developing nations, previous studies of breast cancer screening behavior in Malaysia have used relatively small samples that are not nationally representative, thereby limiting the generalizability of results. Therefore, this study uses nationally representative data from the Malaysia Non-Communicable Disease Surveillance-1 to investigate the role of socio-economic status on breast cancer screening behavior in Malaysia, particularly differences in screening behaviour between ethnic groups. The decisions of 816 women above age 40 in Malaysia to screen for breast cancer using mammography, clinical breast exams (CBE), and breast self-exams (BSE) are modeled using logistic regression. Results indicate that after adjusting for differences in age, education, household income, marital status, and residential location, Malay women are less likely than Chinese and Indian women to utilize mammography, but more likely to perform BSE. Education level and urban residence are positively associated with utilization of each method, but these relationships vary across ethnicity. Higher education levels are strongly related to using each screening method among Chinese women, but have no statistically significant relationship to screening among Malays. © 2011 Wiley Periodicals, Inc.
Cardarelli, Roberto; Reese, David; Roper, Karen L.; Cardarelli, Kathryn; Feltner, Frances J.; Studts, Jamie L.; Knight, Jennifer R.; Armstrong, Debra; Weaver, Anthony; Shaffer, Dana
2017-01-01
For low dose CT lung cancer screening to be effective in curbing disease mortality, efforts are needed to overcome barriers to awareness and facilitate uptake of the current evidence-based screening guidelines. A sequential mixed-methods approach was employed to design a screening campaign utilizing messages developed from community focus groups, followed by implementation of the outreach campaign intervention in two high-risk Kentucky regions. This study reports on rates of awareness and screening in intervention regions, as compared to a control region. PMID:27866066
Niu, Chenqi; Xu, Yuancong; Zhang, Chao; Zhu, Pengyu; Huang, Kunlun; Luo, Yunbo; Xu, Wentao
2018-05-01
As genetically modified (GM) technology develops and genetically modified organisms (GMOs) become more available, GMOs face increasing regulations and pressure to adhere to strict labeling guidelines. A singleplex detection method cannot perform the high-throughput analysis necessary for optimal GMO detection. Combining the advantages of multiplex detection and droplet digital polymerase chain reaction (ddPCR), a single universal primer-multiplex-ddPCR (SUP-M-ddPCR) strategy was proposed for accurate broad-spectrum screening and quantification. The SUP increases efficiency of the primers in PCR and plays an important role in establishing a high-throughput, multiplex detection method. Emerging ddPCR technology has been used for accurate quantification of nucleic acid molecules without a standard curve. Using maize as a reference point, four heterologous sequences ( 35S, NOS, NPTII, and PAT) were selected to evaluate the feasibility and applicability of this strategy. Surprisingly, these four genes cover more than 93% of the transgenic maize lines and serve as preliminary screening sequences. All screening probes were labeled with FAM fluorescence, which allows the signals from the samples with GMO content and those without to be easily differentiated. This fiveplex screening method is a new development in GMO screening. Utilizing an optimal amplification assay, the specificity, limit of detection (LOD), and limit of quantitation (LOQ) were validated. The LOD and LOQ of this GMO screening method were 0.1% and 0.01%, respectively, with a relative standard deviation (RSD) < 25%. This method could serve as an important tool for the detection of GM maize from different processed, commercially available products. Further, this screening method could be applied to other fields that require reliable and sensitive detection of DNA targets.
Liu, Yang; Cao, Fei; Xiong, Hui; Shen, Yanbing; Wang, Min
2016-01-01
To develop a quick method for the preliminarily screening of mutant strains that can accumulate 9α-hydroxyandrost-4-ene-3,17-dione (9α-OH-AD), a high-throughput screening method was presented by applying the principle that 2,4-dinitrophenylhydrazine (DNPH) can react with ketones to produce precipitation. The optimal color assay conditions were the substrate androst-4-ene-3,17-dione (AD) concentration at 2.0 g/L, the ratio of AD to DNPH solution at 1:4, and the sulfuric acid and ethanol solution percentages in DNPH solution at 2% and 35%, respectively. This method was used to preliminarily screen the mutants of Rhodococcus rhodochrous DSM43269, from which the three ones obtained could produce more 9α-OH-AD. This DNPH color assay method not only broadens screening methods and increases screening efficiency in microbial mutation breeding but also establishes a good foundation for obtaining strains for industrial application. PMID:27706217
Liu, Yang; Cao, Fei; Xiong, Hui; Shen, Yanbing; Wang, Min
2016-01-01
To develop a quick method for the preliminarily screening of mutant strains that can accumulate 9α-hydroxyandrost-4-ene-3,17-dione (9α-OH-AD), a high-throughput screening method was presented by applying the principle that 2,4-dinitrophenylhydrazine (DNPH) can react with ketones to produce precipitation. The optimal color assay conditions were the substrate androst-4-ene-3,17-dione (AD) concentration at 2.0 g/L, the ratio of AD to DNPH solution at 1:4, and the sulfuric acid and ethanol solution percentages in DNPH solution at 2% and 35%, respectively. This method was used to preliminarily screen the mutants of Rhodococcus rhodochrous DSM43269, from which the three ones obtained could produce more 9α-OH-AD. This DNPH color assay method not only broadens screening methods and increases screening efficiency in microbial mutation breeding but also establishes a good foundation for obtaining strains for industrial application.
A small-bolt method for screening tree protectants against bark beetles (coleoptera: curculionidae)
B.L. Strom; L.M. Roton
2009-01-01
A simple, small-bolt method was developed and refi ned for evaluating and screening treatments being considered as prophylactics against bark beetles (Coleoptera: Curculionidae: Scolytinae). Using this method, 4 insecticide products (3 active ingredients) were evaluated against the southern pine beetle, Dendroctonus frontalis Zimmermann, intermittently during a period...
Detecting and removing multiplicative spatial bias in high-throughput screening technologies.
Caraus, Iurie; Mazoure, Bogdan; Nadon, Robert; Makarenkov, Vladimir
2017-10-15
Considerable attention has been paid recently to improve data quality in high-throughput screening (HTS) and high-content screening (HCS) technologies widely used in drug development and chemical toxicity research. However, several environmentally- and procedurally-induced spatial biases in experimental HTS and HCS screens decrease measurement accuracy, leading to increased numbers of false positives and false negatives in hit selection. Although effective bias correction methods and software have been developed over the past decades, almost all of these tools have been designed to reduce the effect of additive bias only. Here, we address the case of multiplicative spatial bias. We introduce three new statistical methods meant to reduce multiplicative spatial bias in screening technologies. We assess the performance of the methods with synthetic and real data affected by multiplicative spatial bias, including comparisons with current bias correction methods. We also describe a wider data correction protocol that integrates methods for removing both assay and plate-specific spatial biases, which can be either additive or multiplicative. The methods for removing multiplicative spatial bias and the data correction protocol are effective in detecting and cleaning experimental data generated by screening technologies. As our protocol is of a general nature, it can be used by researchers analyzing current or next-generation high-throughput screens. The AssayCorrector program, implemented in R, is available on CRAN. makarenkov.vladimir@uqam.ca. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com
Besharati, Fereshteh; Karimi-Shahanjarini, Akram; Hazavehei, Seyed Mohammad Mehdi; Bashirian, Saeid; Bagheri, Fahimeh; Faradmal, Javad
2017-08-27
Background: While the incidence rate of the colorectal cancer (CRC) has been increasing over the last three decades in Iran, very limited interventions to increase CRC screening have been developed for Iranian population. The purpose of this study was to describe the use of Intervention Mapping (IM) for applying theory and evidence and considering local contexts to develop a CRC screening program among adults in Iran. Materials and Methods: From April 2014 to July 2016 following the IM process, six steps were formulated and implemented. First a need assessment was conducted involving relevant stakeholders and using focus groups discussions (n=10), individual interviews (n=20), and a household survey (n= 480). Then a matrix of change objectives was developed for each behavioral outcome and theoretical methods and their practical applications were identified to guide intervention development and implementation. A multi-component intervention was developed and piloted. Decision on suitable parts of intervention was made based on feedback of pilot study. Finally, evaluation plan including process and outcome evaluation was generated and conducted to inform future scale up. Results: The needs assessment highlighted factors affecting CRC screening including knowledge, self efficacy, social support and perceived benefit and barriers (financial problems, fear of detection of cancer and etc). Results of needs assessment were used to develop next steps IM. The program utilized methods like information delivery, modeling, and persuasion. Practical applications included video presentation, group discussion, role playing and postcards.This program was assessed through a cluster-randomized controlled trial. Results showed that there were significant differences in CRC screening uptake between intervention groups and control (P<0.001). Conclusions: IM is a useful process in the design of a theory-based intervention addressing CRC screening among Iranian population. Creative Commons Attribution License
High-throughput screening of a CRISPR/Cas9 library for functional genomics in human cells.
Zhou, Yuexin; Zhu, Shiyou; Cai, Changzu; Yuan, Pengfei; Li, Chunmei; Huang, Yanyi; Wei, Wensheng
2014-05-22
Targeted genome editing technologies are powerful tools for studying biology and disease, and have a broad range of research applications. In contrast to the rapid development of toolkits to manipulate individual genes, large-scale screening methods based on the complete loss of gene expression are only now beginning to be developed. Here we report the development of a focused CRISPR/Cas-based (clustered regularly interspaced short palindromic repeats/CRISPR-associated) lentiviral library in human cells and a method of gene identification based on functional screening and high-throughput sequencing analysis. Using knockout library screens, we successfully identified the host genes essential for the intoxication of cells by anthrax and diphtheria toxins, which were confirmed by functional validation. The broad application of this powerful genetic screening strategy will not only facilitate the rapid identification of genes important for bacterial toxicity but will also enable the discovery of genes that participate in other biological processes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Taylor-Pashow, K.; Fondeur, F.; White, T.
Savannah River National Laboratory (SRNL) was tasked with identifying and developing at least one, but preferably two methods for quantifying the suppressor in the Next Generation Solvent (NGS) system. The suppressor is a guanidine derivative, N,N',N"-tris(3,7-dimethyloctyl)guanidine (TiDG). A list of 10 possible methods was generated, and screening experiments were performed for 8 of the 10 methods. After completion of the screening experiments, the non-aqueous acid-base titration was determined to be the most promising, and was selected for further development as the primary method. {sup 1}H NMR also showed promising results from the screening experiments, and this method was selected formore » further development as the secondary method. Other methods, including {sup 36}Cl radiocounting and ion chromatography, also showed promise; however, due to the similarity to the primary method (titration) and the inability to differentiate between TiDG and TOA (tri-n-ocytlamine) in the blended solvent, {sup 1}H NMR was selected over these methods. Analysis of radioactive samples obtained from real waste ESS (extraction, scrub, strip) testing using the titration method showed good results. Based on these results, the titration method was selected as the method of choice for TiDG measurement. {sup 1}H NMR has been selected as the secondary (back-up) method, and additional work is planned to further develop this method and to verify the method using radioactive samples. Procedures for analyzing radioactive samples of both pure NGS and blended solvent were developed and issued for the both methods.« less
The U.S. Environmental Protection Agency is developing and evaluating methods to screen and prioritize large numbers of chemicals for developmental toxicity. Towards this goal, we are exploring methods to detect developmental neurotoxicants in very young larval zebrafish. We have...
Beach, Scott R; Carpenter, Christopher R; Rosen, Tony; Sharps, Phyllis; Gelles, Richard
2016-01-01
This article provides an overview of elder abuse screening and detection methods for community-dwelling and institutionalized older adults, including general issues and challenges for the field. Then, discussions of applications in emergency geriatric care, intimate partner violence (IPV), and child abuse are presented to inform research opportunities in elder abuse screening. The article provides descriptions of emerging screening and detection methods and technologies from the emergency geriatric care and IPV fields. We also discuss the variety of potential barriers to effective screening and detection from the viewpoint of the older adult, caregivers, providers, and the health care system, and we highlight the potential harms and unintended negative consequences of increased screening and mandatory reporting. We argue that research should continue on the development of valid screening methods and tools, but that studies of perceived barriers and potential harms of elder abuse screening among key stakeholders should also be conducted.
Inhibition of Retinoblastoma Protein Inactivation
2016-09-01
Retinoblastoma protein, E2F transcription factor, high throughput screen, drug discovery, x-ray crystallography 16. SECURITY CLASSIFICATION OF: 17...developed a method to perform fragment based screening by x-ray crystallography . 2.0 KEYWORDS Retinoblastoma (Rb) pathway, E2F transcription factor...cancer, cell-cycle inhibition, activation, modulation, inhibition, high throughput screening, fragment-based screening, x-ray crystallography
Screenee perception and health-related quality of life in colorectal cancer screening: a review.
Pizzo, Elena; Pezzoli, Alessandro; Stockbrugger, Reinhold; Bracci, Enrico; Vagnoni, Emidia; Gullini, Sergio
2011-01-01
Screening for colorectal cancer (CRC) has become established to varying degrees in several Western countries for the past 30 years. Because of its effectiveness, screening has been adopted or is planned in a number of other countries. In most countries, the screening method (e.g., fecal occult blood test [FOBT], sigmoidoscopy) is followed by colonoscopy, for verification. In other countries (e.g., United States, Germany), colonoscopy is the preferred first-line investigation method. However, because colonoscopy is considered to be invasive, might be poorly tolerated, and can be associated with complications, the idea of adopting colonoscopy as the primary screening method suffers. Negative effects of screening methods can reduce participation in programs and thereby negate the desired effect on individual and societal health. At present, there is no generally accepted method either to assess the perception and satisfaction of patients screened or the outcome of the screening procedures in CRC. In this review, we discuss the past development and present availability of instruments to measure health-related quality of life (HRQoL), the scarce studies in which such instruments have been used in screening campaigns, and the findings. We suggest the creation of a specific instrument for the assessment of HRQoL in CRC screening. Copyright © 2011 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.
Design of compound libraries for fragment screening
NASA Astrophysics Data System (ADS)
Blomberg, Niklas; Cosgrove, David A.; Kenny, Peter W.; Kolmodin, Karin
2009-08-01
Approaches to the design of libraries for fragment screening are illustrated with reference to a 20 k generic fragment screening library and a 1.2 k generic NMR screening library. Tools and methods for library design that have been developed within AstraZeneca are described, including Foyfi fingerprints and the Flush program for neighborhood characterization. It will be shown how Flush and the BigPicker, which selects maximally diverse sets of compounds, are used to apply the Core and Layer method for library design. Approaches to partitioning libraries into cocktails are also described.
Screening Tools to Estimate Mold Burdens in Homes
Objective: The objective of this study was to develop screening tools that could be used to estimate the mold burden in a home which would indicate whether more detailed testing might be useful. Methods: Previously, in the American Healthy Home Survey, a DNA-based method of an...
Goldie, Sue
2006-11-01
Cervical cancer remains a leading cause of cancer death among women living in low-resource settings. In the last 3 decades, cytologic screening has -in theory -been available and yet more than 6 million women have died of this preventable disease. The necessary resources, infrastructure, and technological expertise, together with the need for repeated screenings at regular intervals, make cytologic screening difficult to implement in poor countries. As noncytologic approaches for the detection of HPV, simple visual screening methods for anogenital lesions caused by HPV, and the availability of an HPV-16/18 vaccine will enhance the linkage between screening and treatment, multiple factors will need to be considered when designing new, or modifying existing prevention strategies. Countryspecific decisions regarding the best strategy for cervical cancer control will need to rely on data from many sources and take into account complex epidemiologic, economic, social, political, and cultural factors, and be made despite uncertainty and incomplete information. A rigorous decision analytic approach using computerbased modeling methods enables linkage of the knowledge gained from empirical studies to real-world situations. This chapter provides an introduction to these methods, reviews lessons learned from cost-effectiveness analyses of cervical cancer screening in developed and developing countries, and emphasizes important qualitative themes to consider in designing cervical cancer prevention policies.
Newborn hearing screening update for midwifery practice.
Narrigan, D
2000-01-01
Neonatal identification of congenital hearing impairment allows interventions during the first 3 years, the critical period for language and speech development. Two recently developed biophysical testing methods offer simple, accurate, and relatively inexpensive means to identify the one to three in 1,000 healthy newborns with hearing loss. Universal screening for auditory system integrity is advocated, because almost half of all newborns with hearing impairment have no risk factors associated with this impairment. Critics of universal screening cite the high rate of false positive tests (up to 7%), which increases program costs from follow-up and re-testing large numbers of infants to ensure identifying the few affected infants. As of early 2000, 24 states had introduced some type of auditory screening program, and the U.S. Congress had passed legislation with appropriations mandating state-based auditory screening for all newborns. Midwives practicing in states already mandating biophysical screening need to comply with their local requirements; those in other states may voluntarily incorporate new auditory test methods into practice.
Elkin, L L; Harden, D G; Saldanha, S; Ferguson, H; Cheney, D L; Pieniazek, S N; Maloney, D P; Zewinski, J; O'Connell, J; Banks, M
2015-06-01
Compound pooling, or multiplexing more than one compound per well during primary high-throughput screening (HTS), is a controversial approach with a long history of limited success. Many issues with this approach likely arise from long-term storage of library plates containing complex mixtures of compounds at high concentrations. Due to the historical difficulties with using multiplexed library plates, primary HTS often uses a one-compound-one-well approach. However, as compound collections grow, innovative strategies are required to increase the capacity of primary screening campaigns. Toward this goal, we have developed a novel compound pooling method that increases screening capacity without compromising data quality. This method circumvents issues related to the long-term storage of complex compound mixtures by using acoustic dispensing to enable "just-in-time" compound pooling directly in the assay well immediately prior to assay. Using this method, we can pool two compounds per well, effectively doubling the capacity of a primary screen. Here, we present data from pilot studies using just-in-time pooling, as well as data from a large >2-million-compound screen using this approach. These data suggest that, for many targets, this method can be used to vastly increase screening capacity without significant reduction in the ability to detect screening hits. © 2015 Society for Laboratory Automation and Screening.
Canine Hip Dysplasia: Diagnostic Imaging.
Butler, J Ryan; Gambino, Jennifer
2017-07-01
Diagnostic imaging is the principal method used to screen for and diagnose hip dysplasia in the canine patient. Multiple techniques are available, each having advantages, disadvantages, and limitations. Hip-extended radiography is the most used method and is best used as a screening tool and for assessment for osteoarthritis. Distraction radiographic methods such as the PennHip method allow for improved detection of laxity and improved ability to predict future osteoarthritis development. More advanced techniques such as MRI, although expensive and not widely available, may improve patient screening and allow for improved assessment of cartilage health. Copyright © 2017 Elsevier Inc. All rights reserved.
Chau, Hong Thi Cam; Kadokami, Kiwao; Ifuku, Tomomi; Yoshida, Yusuke
2017-12-01
A comprehensive screening method for 311 organic compounds with a wide range of physicochemical properties (log Pow -2.2-8.53) in water samples was developed by combining solid-phase extraction with liquid chromatography-high-resolution time-of-flight mass spectrometry. Method optimization using 128 pesticides revealed that tandem extraction with styrene-divinylbenzene polymer and activated carbon solid-phase extraction cartridges at pH 7.0 was optimal. The developed screening method was able to extract 190 model compounds with average recovery of 80.8% and average relative standard deviations (RSD) of 13.5% from spiked reagent water at 0.20 μg L -1 , and 87.1% recovery and 10.8% RSD at 0.05 μg L -1 . Spike-recovery testing (0.20 μg L -1 ) using real sewage treatment plant effluents resulted in an average recovery and average RSD of 190 model compounds of 77.4 and 13.1%, respectively. The method was applied to the influent and effluent of five sewage treatment plants in Kitakyushu, Japan, with 29 out of 311 analytes being observed at least once. The results showed that this method can screen for a large number of chemicals with a wide range of physicochemical properties quickly and at low operational cost, something that is difficult to achieve using conventional analytical methods. This method will find utility in target screening of hazardous chemicals with a high risk in environmental waters, and for confirming the safety of water after environmental incidents.
Smartphone-Based Hearing Screening in Noisy Environments
Na, Youngmin; Joo, Hyo Sung; Yang, Hyejin; Kang, Soojin; Hong, Sung Hwa; Woo, Jihwan
2014-01-01
It is important and recommended to detect hearing loss as soon as possible. If it is found early, proper treatment may help improve hearing and reduce the negative consequences of hearing loss. In this study, we developed smartphone-based hearing screening methods that can ubiquitously test hearing. However, environmental noise generally results in the loss of ear sensitivity, which causes a hearing threshold shift (HTS). To overcome this limitation in the hearing screening location, we developed a correction algorithm to reduce the HTS effect. A built-in microphone and headphone were calibrated to provide the standard units of measure. The HTSs in the presence of either white or babble noise were systematically investigated to determine the mean HTS as a function of noise level. When the hearing screening application runs, the smartphone automatically measures the environmental noise and provides the HTS value to correct the hearing threshold. A comparison to pure tone audiometry shows that this hearing screening method in the presence of noise could closely estimate the hearing threshold. We expect that the proposed ubiquitous hearing test method could be used as a simple hearing screening tool and could alert the user if they suffer from hearing loss. PMID:24926692
Conditional screening for ultra-high dimensional covariates with survival outcomes
Hong, Hyokyoung G.; Li, Yi
2017-01-01
Identifying important biomarkers that are predictive for cancer patients’ prognosis is key in gaining better insights into the biological influences on the disease and has become a critical component of precision medicine. The emergence of large-scale biomedical survival studies, which typically involve excessive number of biomarkers, has brought high demand in designing efficient screening tools for selecting predictive biomarkers. The vast amount of biomarkers defies any existing variable selection methods via regularization. The recently developed variable screening methods, though powerful in many practical setting, fail to incorporate prior information on the importance of each biomarker and are less powerful in detecting marginally weak while jointly important signals. We propose a new conditional screening method for survival outcome data by computing the marginal contribution of each biomarker given priorily known biological information. This is based on the premise that some biomarkers are known to be associated with disease outcomes a priori. Our method possesses sure screening properties and a vanishing false selection rate. The utility of the proposal is further confirmed with extensive simulation studies and analysis of a diffuse large B-cell lymphoma dataset. We are pleased to dedicate this work to Jack Kalbfleisch, who has made instrumental contributions to the development of modern methods of analyzing survival data. PMID:27933468
Rafii, Forough; Rahimparvar, Seyedeh Fatemeh Vasegh; Mehrdad, Neda; Keramat, Afsaneh
2017-01-01
Introduction Risk of developing type 2 diabetes is increased in women with previous gestational diabetes mellitus (GDM). Postpartum glycemic screening is recommended in women with recent GDM. But this screening rate is low and the reasons are unclear. The aim of this study was to explore the experiences of Iranian women with recent GDM on barriers of postpartum screening for diabetes. Methods This qualitative study was conducted in Tehran, Iran in 2016. Semi-structured interview was used for data collection. 22 women with recent GDM were interviewed. These women gave birth in Tehran hospitals at a minimum of 6 months before interview. The missed screening defined as not attending to laboratory for Fasting Blood Sugar and/or Oral Glucose Tolerance Test, 6 week to 6 month after their child birthing. The data was analyzed by content analysis method. Results Themes and sub-themes that illustrated the barriers to postpartum diabetes screening were: inadequate education (about developing diabetes in the future, implementation of the screening, and glucometer validity in diagnosis of diabetes), perceiving the screening as difficult (feeling comfortable with the glucometer, poor laboratory conditions, issues related to the baby/babies, and financial problems), improper attitudes toward the screening (unwilling to get diagnosed, not giving priority to oneself, having false beliefs) and procrastination (gap to intention and action, self-deception and self-regulation failure). Conclusion Women with recent GDM reported several barriers for postpartum diabetes screening. This study help to develop the evidence-based interventions for improving this screening rate. PMID:28451031
Accelerated Colorimetric Micro-assay for Screening Mold Inhibitors
Carol A. Clausen; Vina W. Yang
2014-01-01
Rapid quantitative laboratory test methods are needed to screen potential antifungal agents. Existing laboratory test methods are relatively time consuming, may require specialized test equipment and rely on subjective visual ratings. A quantitative, colorimetric micro-assay has been developed that uses XTT tetrazolium salt to metabolically assess mold spore...
Gagnon, J.; Lévesque, E.; Borduas, F.; Chiquette, J.; Diorio, C.; Duchesne, N.; Dumais, M.; Eloy, L.; Foulkes, W.; Gervais, N.; Lalonde, L.; L’Espérance, B.; Meterissian, S.; Provencher, L.; Richard, J.; Savard, C.; Trop, I.; Wong, N.; Knoppers, B.M.; Simard, J.
2016-01-01
In recent years, risk stratification has sparked interest as an innovative approach to disease screening and prevention. The approach effectively personalizes individual risk, opening the way to screening and prevention interventions that are adapted to subpopulations. The international perspective project, which is developing risk stratification for breast cancer, aims to support the integration of its screening approach into clinical practice through comprehensive tool-building. Policies and guidelines for risk stratification—unlike those for population screening programs, which are currently well regulated—are still under development. Indeed, the development of guidelines for risk stratification reflects the translational aspects of perspective. Here, we describe the risk stratification process that was devised in the context of perspective, and we then explain the consensus-based method used to develop recommendations for breast cancer screening and prevention in a risk-stratification approach. Lastly, we discuss how the recommendations might affect current screening policies. PMID:28050152
In response to the 1996 legislative mandate for an endocrine screening and testing program, we are helping develop, standardize and validate relatively sensitive, robust and relatively simple methods for in vitro screening of chemicals that affect estrogen, and androgen function ...
Cash, Jennifer N; Angerman, Elizabeth B; Kirby, R Jason; Merck, Lisa; Seibel, William L; Wortman, Matthew D; Papoian, Ruben; Nelson, Sandra; Thompson, Thomas B
2013-08-01
Myostatin, a member of the transforming growth factor (TGF)-β family of secreted ligands, is a strong negative regulator of muscle growth. As such, therapeutic inhibitors of myostatin are actively being investigated for their potential in the treatment of muscle-wasting diseases such as muscular dystrophy and sarcopenia. Here, we sought to develop a high-throughput screening (HTS) method for small-molecule inhibitors that target myostatin. We created a HEK293 stable cell line that expresses the (CAGA)12-luciferase reporter construct and robustly responds to signaling of certain classes of TGF-β family ligands. After optimization and miniaturization of the assay to a 384-well format, we successfully screened a library of compounds for inhibition of myostatin and the closely related activin A. Selection of some of the tested compounds was directed by in silico screening against myostatin, which led to an enrichment of target hits as compared with random selection. Altogether, we present an HTS method that will be useful for screening potential inhibitors of not only myostatin but also many other ligands of the TGF-β family.
Developing a Bacteroides System for Function-Based Screening of DNA from the Human Gut Microbiome.
Lam, Kathy N; Martens, Eric C; Charles, Trevor C
2018-01-01
Functional metagenomics is a powerful method that allows the isolation of genes whose role may not have been predicted from DNA sequence. In this approach, first, environmental DNA is cloned to generate metagenomic libraries that are maintained in Escherichia coli, and second, the cloned DNA is screened for activities of interest. Typically, functional screens are carried out using E. coli as a surrogate host, although there likely exist barriers to gene expression, such as lack of recognition of native promoters. Here, we describe efforts to develop Bacteroides thetaiotaomicron as a surrogate host for screening metagenomic DNA from the human gut. We construct a B. thetaiotaomicron-compatible fosmid cloning vector, generate a fosmid clone library using DNA from the human gut, and show successful functional complementation of a B. thetaiotaomicron glycan utilization mutant. Though we were unable to retrieve the physical fosmid after complementation, we used genome sequencing to identify the complementing genes derived from the human gut microbiome. Our results demonstrate that the use of B. thetaiotaomicron to express metagenomic DNA is promising, but they also exemplify the challenges that can be encountered in the development of new surrogate hosts for functional screening. IMPORTANCE Human gut microbiome research has been supported by advances in DNA sequencing that make it possible to obtain gigabases of sequence data from metagenomes but is limited by a lack of knowledge of gene function that leads to incomplete annotation of these data sets. There is a need for the development of methods that can provide experimental data regarding microbial gene function. Functional metagenomics is one such method, but functional screens are often carried out using hosts that may not be able to express the bulk of the environmental DNA being screened. We expand the range of current screening hosts and demonstrate that human gut-derived metagenomic libraries can be introduced into the gut microbe Bacteroides thetaiotaomicron to identify genes based on activity screening. Our results support the continuing development of genetically tractable systems to obtain information about gene function.
Label-free screening of foodborne Salmonella using surface plasmon resonance imaging
USDA-ARS?s Scientific Manuscript database
Since 15 pathogens cause approximately 95% of the foodborne infections, it is desirable to develop rapid and simultaneous screening methods for these major pathogens. In this study, we developed an immunoassay for Salmonella based on surface plasmon resonance imaging (SPRi). The sensor surface modif...
Evaluation of parameters of color profile models of LCD and LED screens
NASA Astrophysics Data System (ADS)
Zharinov, I. O.; Zharinov, O. O.
2017-12-01
The purpose of the research relates to the problem of parametric identification of the color profile model of LCD (liquid crystal display) and LED (light emitting diode) screens. The color profile model of a screen is based on the Grassmann’s Law of additive color mixture. Mathematically the problem is to evaluate unknown parameters (numerical coefficients) of the matrix transformation between different color spaces. Several methods of evaluation of these screen profile coefficients were developed. These methods are based either on processing of some colorimetric measurements or on processing of technical documentation data.
NASA Technical Reports Server (NTRS)
Cady, E. C.
1977-01-01
A design analysis, is developed based on experimental data, to predict the effects of transient flow and pressure surges (caused either by valve or pump operation, or by boiling of liquids in warm lines) on the retention performance of screen acquisition systems. A survey of screen liquid acquisition system applications was performed to determine appropriate system environment and classification. A screen model was developed which assumed that the screen device was a uniformly distributed composite orthotropic structure, and which accounted for liquid inflow/outflow, gas ingestion quality, screen stress, and liquid spill. A series of 177 tests using 13 specimens (5 screen meshes, 4 screen device construction/backup methods, and 2 orientations) with three test fluids (isopropyl alcohol, Freon 114, and LH2) provided data which verified important features of the screen model and resulted in a design tool which could accurately predict the transient startup performance acquisition devices.
Fox, Aaron S; Bonacci, Jason; McLean, Scott G; Spittle, Michael; Saunders, Natalie
2016-05-01
Laboratory-based measures provide an accurate method to identify risk factors for anterior cruciate ligament (ACL) injury; however, these methods are generally prohibitive to the wider community. Screening methods that can be completed in a field or clinical setting may be more applicable for wider community use. Examination of field-based screening methods for ACL injury risk can aid in identifying the most applicable method(s) for use in these settings. The objective of this systematic review was to evaluate and compare field-based screening methods for ACL injury risk to determine their efficacy of use in wider community settings. An electronic database search was conducted on the SPORTDiscus™, MEDLINE, AMED and CINAHL databases (January 1990-July 2015) using a combination of relevant keywords. A secondary search of the same databases, using relevant keywords from identified screening methods, was also undertaken. Studies identified as potentially relevant were independently examined by two reviewers for inclusion. Where consensus could not be reached, a third reviewer was consulted. Original research articles that examined screening methods for ACL injury risk that could be undertaken outside of a laboratory setting were included for review. Two reviewers independently assessed the quality of included studies. Included studies were categorized according to the screening method they examined. A description of each screening method, and data pertaining to the ability to prospectively identify ACL injuries, validity and reliability, recommendations for identifying 'at-risk' athletes, equipment and training required to complete screening, time taken to screen athletes, and applicability of the screening method across sports and athletes were extracted from relevant studies. Of 1077 citations from the initial search, a total of 25 articles were identified as potentially relevant, with 12 meeting all inclusion/exclusion criteria. From the secondary search, eight further studies met all criteria, resulting in 20 studies being included for review. Five ACL-screening methods-the Landing Error Scoring System (LESS), Clinic-Based Algorithm, Observational Screening of Dynamic Knee Valgus (OSDKV), 2D-Cam Method, and Tuck Jump Assessment-were identified. There was limited evidence supporting the use of field-based screening methods in predicting ACL injuries across a range of populations. Differences relating to the equipment and time required to complete screening methods were identified. Only screening methods for ACL injury risk were included for review. Field-based screening methods developed for lower-limb injury risk in general may also incorporate, and be useful in, screening for ACL injury risk. Limited studies were available relating to the OSDKV and 2D-Cam Method. The LESS showed predictive validity in identifying ACL injuries, however only in a youth athlete population. The LESS also appears practical for community-wide use due to the minimal equipment and set-up/analysis time required. The Clinic-Based Algorithm may have predictive value for ACL injury risk as it identifies athletes who exhibit high frontal plane knee loads during a landing task, but requires extensive additional equipment and time, which may limit its application to wider community settings.
Weimar, M R; Cheung, J; Dey, D; McSweeney, C; Morrison, M; Kobayashi, Y; Whitman, W B; Carbone, V; Schofield, L R; Ronimus, R S; Cook, G M
2017-08-01
Hydrogenotrophic methanogens typically require strictly anaerobic culturing conditions in glass tubes with overpressures of H 2 and CO 2 that are both time-consuming and costly. To increase the throughput for screening chemical compound libraries, 96-well microtiter plate methods for the growth of a marine (environmental) methanogen Methanococcus maripaludis strain S2 and the rumen methanogen Methanobrevibacter species AbM4 were developed. A number of key parameters (inoculum size, reducing agents for medium preparation, assay duration, inhibitor solvents, and culture volume) were optimized to achieve robust and reproducible growth in a high-throughput microtiter plate format. The method was validated using published methanogen inhibitors and statistically assessed for sensitivity and reproducibility. The Sigma-Aldrich LOPAC library containing 1,280 pharmacologically active compounds and an in-house natural product library (120 compounds) were screened against M. maripaludis as a proof of utility. This screen identified a number of bioactive compounds, and MIC values were confirmed for some of them against M. maripaludis and M. AbM4. The developed method provides a significant increase in throughput for screening compound libraries and can now be used to screen larger compound libraries to discover novel methanogen-specific inhibitors for the mitigation of ruminant methane emissions. IMPORTANCE Methane emissions from ruminants are a significant contributor to global greenhouse gas emissions, and new technologies are required to control emissions in the agriculture technology (agritech) sector. The discovery of small-molecule inhibitors of methanogens using high-throughput phenotypic (growth) screening against compound libraries (synthetic and natural products) is an attractive avenue. However, phenotypic inhibitor screening is currently hindered by our inability to grow methanogens in a high-throughput format. We have developed, optimized, and validated a high-throughput 96-well microtiter plate assay for growing environmental and rumen methanogens. Using this platform, we identified several new inhibitors of methanogen growth, demonstrating the utility of this approach to fast track the development of methanogen-specific inhibitors for controlling ruminant methane emissions. Copyright © 2017 American Society for Microbiology.
Colorimetric micro-assay for accelerated screening of mould inhibitors
Carol A. Clausen; Vina W. Yang
2013-01-01
Since current standard laboratory methods are time-consuming macro-assays that rely on subjective visual ratings of mould growth, rapid and quantitative laboratory methods are needed to screen potential mould inhibitors for use in and on cellulose-based products. A colorimetric micro-assay has been developed that uses XTT tetrazolium salt to enzymatically assess...
Goldie, Sue
2006-11-01
Cervical cancer remains a leading cause of cancer death among women living in low-resource settings. In the last 3 decades, cytologic screening has -in theory -been available and yet more than 6 million women have died of this preventable disease. The necessary resources, infrastructure, and technological expertise, together with the need for repeated screenings at regular intervals, make cytologic screening difficult to implement in poor countries. As noncytologic approaches for the detection of HPV, simple visual screening methods for anogenital lesions caused by HPV, and the availability of an HPV-16/18 vaccine will enhance the linkage between screening and treatment, multiple factors will need to be considered when designing new, or modifying existing prevention strategies. Countryspecific decisions regarding the best strategy for cervical cancer control will need to rely on data from many sources and take into account complex epidemiologic, economic, social, political, and cultural factors, and be made despite uncertainty and incomplete information. A rigorous decision analytic approach using computerbased modeling methods enables linkage of the knowledge gained from empirical studies to real-world situations. This chapter provides an introduction to these methods, reviews lessons learned from cost-effectiveness analyses of cervical cancer screening in developed and developing countries, and emphasizes important qualitative themes to consider in designing cervical cancer prevention policies. © 2006 International Federation of Gynecology and Obstetrics.
NASA Astrophysics Data System (ADS)
Drwal, Malgorzata N.; Agama, Keli; Pommier, Yves; Griffith, Renate
2013-12-01
Purely structure-based pharmacophores (SBPs) are an alternative method to ligand-based approaches and have the advantage of describing the entire interaction capability of a binding pocket. Here, we present the development of SBPs for topoisomerase I, an anticancer target with an unusual ligand binding pocket consisting of protein and DNA atoms. Different approaches to cluster and select pharmacophore features are investigated, including hierarchical clustering and energy calculations. In addition, the performance of SBPs is evaluated retrospectively and compared to the performance of ligand- and complex-based pharmacophores. SBPs emerge as a valid method in virtual screening and a complementary approach to ligand-focussed methods. The study further reveals that the choice of pharmacophore feature clustering and selection methods has a large impact on the virtual screening hit lists. A prospective application of the SBPs in virtual screening reveals that they can be used successfully to identify novel topoisomerase inhibitors.
Breivik, Knut; Arnot, Jon A; Brown, Trevor N; McLachlan, Michael S; Wania, Frank
2012-08-01
Quantitative knowledge of organic chemical release into the environment is essential to understand and predict human exposure as well as to develop rational control strategies for any substances of concern. While significant efforts have been invested to characterize and screen organic chemicals for hazardous properties, relatively less effort has been directed toward estimating emissions and hence also risks. Here, a rapid throughput method to estimate emissions of discrete organic chemicals in commerce has been developed, applied and evaluated to support screening studies aimed at ranking and identifying chemicals of potential concern. The method builds upon information in the European Union Technical Guidance Document and utilizes information on quantities in commerce (production and/or import rates), chemical function (use patterns) and physical-chemical properties to estimate emissions to air, soil and water within the OECD for five stages of the chemical life-cycle. The method is applied to 16,029 discrete substances (identified by CAS numbers) from five national and international high production volume lists. As access to consistent input data remains fragmented or even impossible, particular attention is given to estimating, evaluating and discussing uncertainties in the resulting emission scenarios. The uncertainty for individual substances typically spans 3 to 4 orders of magnitude for this initial tier screening method. Information on uncertainties in emissions is useful as any screening or categorization methods which solely rely on threshold values are at risk of leading to a significant number of either false positives or false negatives. A limited evaluation of the screening method's estimates for a sub-set of about 100 substances, compared against independent and more detailed emission scenarios presented in various European Risk Assessment Reports, highlights that up-to-date and accurate information on quantities in commerce as well as a detailed breakdown on chemical function are critically needed for developing more realistic emission scenarios.
Towards Automated Screening of Two-dimensional Crystals
Cheng, Anchi; Leung, Albert; Fellmann, Denis; Quispe, Joel; Suloway, Christian; Pulokas, James; Carragher, Bridget; Potter, Clinton S.
2007-01-01
Screening trials to determine the presence of two-dimensional (2D) protein crystals suitable for three-dimensional structure determination using electron crystallography is a very labor-intensive process. Methods compatible with fully automated screening have been developed for the process of crystal production by dialysis and for producing negatively stained grids of the resulting trials. Further automation via robotic handling of the EM grids, and semi-automated transmission electron microscopic imaging and evaluation of the trial grids is also possible. We, and others, have developed working prototypes for several of these tools and tested and evaluated them in a simple screen of 24 crystallization conditions. While further development of these tools is certainly required for a turn-key system, the goal of fully automated screening appears to be within reach. PMID:17977016
Shankar, Manoharan; Priyadharshini, Ramachandran; Gunasekaran, Paramasamy
2009-08-01
An image analysis-based method for high throughput screening of an alpha-amylase mutant library using chromogenic assays was developed. Assays were performed in microplates and high resolution images of the assay plates were read using the Virtual Microplate Reader (VMR) script to quantify the concentration of the chromogen. This method is fast and sensitive in quantifying 0.025-0.3 mg starch/ml as well as 0.05-0.75 mg glucose/ml. It was also an effective screening method for improved alpha-amylase activity with a coefficient of variance of 18%.
Development of chemical compositions for impervious screens in rocks
NASA Astrophysics Data System (ADS)
Kurlenya, MV; Serdyukov, SV; Shilova, TV; Patutin, AV
2017-02-01
The paper presents the method to create anti-seepage screens by hydraulic fracturing with three-component polyurethane mixture. The proposed working fluids and their pumping circuits allow creation of a fracture and an adjacent insulation layer. Gas permeability of porous medium is determined at limit consumption of reagents per insulating screen unit area.
Using Spelling to Screen Bilingual Kindergarteners at Risk for Reading Difficulties
ERIC Educational Resources Information Center
Chua, Shi Min; Rickard Liow, Susan J.; Yeong, Stephanie H. M.
2016-01-01
For bilingual children, the results of language and literacy screening tools are often hard to interpret. This leads to late referral for specialized assessment or inappropriate interventions. To facilitate the early identification of reading difficulties in English, we developed a method of screening that is theory-driven yet suitable for…
Accuracy of a Screening Tool for Early Identification of Language Impairment
ERIC Educational Resources Information Center
Uilenburg, Noëlle; Wiefferink, Karin; Verkerk, Paul; van Denderen, Margot; van Schie, Carla; Oudesluys-Murphy, Ann-Marie
2018-01-01
Purpose: A screening tool called the "VTO Language Screening Instrument" (VTO-LSI) was developed to enable more uniform and earlier detection of language impairment. This report, consisting of 2 retrospective studies, focuses on the effects of using the VTO-LSI compared to regular detection procedures. Method: Study 1 retrospectively…
"Pepsi": A Screening and Programming Tool for Understanding the Whole Child.
ERIC Educational Resources Information Center
Ellsworth, J'Anne
1996-01-01
This article discusses using "PEPSI", a screening and programming method that evaluates the physical, emotional, philosophical, social, and intellectual levels of development in children with disabilities. The steps in the PEPSI screening process are described and a case study is provided. A chart depicting indicators in teaching respect for self…
Screening and Assessment of Young Children at Developmental Risk.
ERIC Educational Resources Information Center
Meier, John
Presented in the monograph are current or proposed methods for screening and assessing children, from birth to 5 years of age, who have diverse developmental disorders or who are at risk, and whose mental and physical development will benefit from early identification and intervention. Considered in relation to general screening are a screening…
Mehta, S; Guy, S D; Bryce, T N; Craven, B C; Finnerup, N B; Hitzig, S L; Orenczuk, S; Siddall, P J; Widerström-Noga, E; Casalino, A; Côté, I; Harvey, D; Kras-Dupuis, A; Lau, B; Middleton, J W; Moulin, D E; O'Connell, C; Parrent, A G; Potter, P; Short, C; Teasell, R; Townson, A; Truchon, C; Wolfe, D; Bradbury, C L; Loh, E
2016-08-01
Clinical practice guidelines. To develop the first Canadian clinical practice guidelines for screening and diagnosis of neuropathic pain in people with spinal cord injury (SCI). The guidelines are relevant for inpatient and outpatient SCI rehabilitation settings in Canada. The CanPainSCI Working Group reviewed evidence to address clinical questions regarding screening and diagnosis of neuropathic pain after SCI. A consensus process was followed to achieve agreement on recommendations and clinical considerations. Twelve recommendations, based on expert consensus, were developed for the screening and diagnosis of neuropathic pain after SCI. The recommendations address methods for assessment, documentation tools, team member accountability, frequency of screening and considerations for diagnostic investigation. Important clinical considerations accompany each recommendation. The expert Working Group developed recommendations for the screening and diagnosis of neuropathic pain after SCI that should be used to inform practice.
2013-01-01
Background Efficient screening of bacterial artificial chromosome (BAC) libraries with polymerase chain reaction (PCR)-based markers is feasible provided that a multidimensional pooling strategy is implemented. Single nucleotide polymorphisms (SNPs) can be screened in multiplexed format, therefore this marker type lends itself particularly well for medium- to high-throughput applications. Combining the power of multiplex-PCR assays with a multidimensional pooling system may prove to be especially challenging in a polyploid genome. In polyploid genomes two classes of SNPs need to be distinguished, polymorphisms between accessions (intragenomic SNPs) and those differentiating between homoeologous genomes (intergenomic SNPs). We have assessed whether the highly parallel Illumina GoldenGate® Genotyping Assay is suitable for the screening of a BAC library of the polyploid Brassica napus genome. Results A multidimensional screening platform was developed for a Brassica napus BAC library which is composed of almost 83,000 clones. Intragenomic and intergenomic SNPs were included in Illumina’s GoldenGate® Genotyping Assay and both SNP classes were used successfully for screening of the multidimensional BAC pools of the Brassica napus library. An optimized scoring method is proposed which is especially valuable for SNP calling of intergenomic SNPs. Validation of the genotyping results by independent methods revealed a success of approximately 80% for the multiplex PCR-based screening regardless of whether intra- or intergenomic SNPs were evaluated. Conclusions Illumina’s GoldenGate® Genotyping Assay can be efficiently used for screening of multidimensional Brassica napus BAC pools. SNP calling was specifically tailored for the evaluation of BAC pool screening data. The developed scoring method can be implemented independently of plant reference samples. It is demonstrated that intergenomic SNPs represent a powerful tool for BAC library screening of a polyploid genome. PMID:24010766
Diagnostic methods for platelet bacteria screening: current status and developments.
Störmer, Melanie; Vollmer, Tanja
2014-02-01
Bacterial contamination of blood components and the prevention of transfusion-associated bacterial infection still remains a major challenge in transfusion medicine. Over the past few decades, a significant reduction in the transmission of viral infections has been achieved due to the introduction of mandatory virus screening. Platelet concentrates (PCs) represent one of the highest risks for bacterial infection. This is due to the required storage conditions for PCs in gas-permeable containers at room temperature with constant agitation, which support bacterial proliferation from low contamination levels to high titers. In contrast to virus screening, since 1997 in Germany bacterial testing of PCs is only performed as a routine quality control or, since 2008, to prolong the shelf life to 5 days. In general, bacterial screening of PCs by cultivation methods is implemented by the various blood services. Although these culturing systems will remain the gold standard, the significance of rapid methods for screening for bacterial contamination has increased over the last few years. These new methods provide powerful tools for increasing the bacterial safety of blood components. This article summarizes the course of policies and provisions introduced to increase bacterial safety of blood components in Germany. Furthermore, we give an overview of the different diagnostic methods for bacterial screening of PCs and their current applicability in routine screening processes.
ScreenCube: A 3D Printed System for Rapid and Cost-Effective Chemical Screening in Adult Zebrafish.
Monstad-Rios, Adrian T; Watson, Claire J; Kwon, Ronald Y
2018-02-01
Phenotype-based small molecule screens in zebrafish embryos and larvae have been successful in accelerating pathway and therapeutic discovery for diverse biological processes. Yet, the application of chemical screens to adult physiologies has been relatively limited due to additional demands on cost, space, and labor associated with screens in adult animals. In this study, we present a 3D printed system and methods for intermittent drug dosing that enable rapid and cost-effective chemical administration in adult zebrafish. Using prefilled screening plates, the system enables dosing of 96 fish in ∼3 min, with a 10-fold reduction in drug quantity compared to that used in previous chemical screens in adult zebrafish. We characterize water quality kinetics during immersion in the system and use these kinetics to rationally design intermittent dosing regimens that result in 100% fish survival. As a demonstration of system fidelity, we show the potential to identify two known chemical inhibitors of adult tail fin regeneration, cyclopamine and dorsomorphin. By developing methods for rapid and cost-effective chemical administration in adult zebrafish, this study expands the potential for small molecule discovery in postembryonic models of development, disease, and regeneration.
Real-time and online screening method for materials emitting volatile organic compounds
NASA Astrophysics Data System (ADS)
Kim, Changhyuk; Sul, Yong Tae; Pui, David Y. H.
2016-09-01
In the semiconductor industry, volatile organic compounds (VOCs) in the cleanroom air work as airborne molecular contamination, which reduce the production yield of semiconductor chips by forming nanoparticles and haze on silicon wafers and photomasks under ultraviolet irradiation during photolithography processes. Even though VOCs in outdoor air are removed by gas filters, VOCs can be emitted from many kinds of materials used in cleanrooms, such as organic solvents and construction materials (e.g., adhesives, flame retardants and sealants), threatening the production of semiconductors. Therefore, finding new replacements that emit lower VOCs is now essential in the semiconductor industry. In this study, we developed a real-time and online method to screen materials for developing the replacements by converting VOCs into nanoparticles under soft X-ray irradiation. This screening method was applied to measure VOCs emitted from different kinds of organic solvents and adhesives. Our results showed good repeatability and high sensitivity for VOCs, which come from aromatic compounds, some alcohols and all tested adhesives (Super glue and cleanroom-use adhesives). In addition, the overall trend of measured VOCs from cleanroom-use adhesives was well matched with those measured by a commercial thermal desorption-gas chromatography-mass spectrometry, which is a widely used off-line method for analyzing VOCs. Based on the results, this screening method can help accelerate the developing process for reducing VOCs in cleanrooms.
Eugster, Albert; Murmann, Petra; Kaenzig, Andre; Breitenmoser, Alda
2014-10-01
In routine analysis screening methods based on real-time PCR (polymerase chain reaction) are most commonly used for the detection of genetically modified (GM) plant material in food and feed. Screening tests are based on sequences frequently used for GM development, allowing the detection of a large number of GMOs (genetically modified organisms). Here, we describe the development and validation of a tetraplex real-time PCR screening assay comprising detection systems for the regulatory genes Cauliflower Mosaic Virus 35S promoter, Agrobacterium tumefaciens nos terminator, Cauliflower Mosaic Virus 35S terminator and Figwort Mosaic Virus 34S promoter. Three of the four primer and probe combinations have already been published elsewhere, whereas primers and probe for the 35S terminator have been developed in-house. Adjustment of primer and probe concentrations revealed a high PCR sensitivity with insignificant physical cross-talk between the four detection channels. The sensitivity of each PCR-system is sufficient to detect a GMO concentration as low as 0.05% of the containing respective element. The specificity of the described tetraplex is high when tested on DNA from GM maize, soy, rapeseed and tomato. We also demonstrate the robustness of the system by inter-laboratory tests. In conclusion, this method provides a sensitive and reliable screening procedure for the detection of the most frequently used regulatory elements present in GM crops either authorised or unauthorised for food.
The need to develop novel screening methods for developmental neurotoxicity in order to alleviate the demands of cost, time, and animals required for in vivo toxicity studies is well recognized. Accordingly, the U.S. EPA launched the ToxCast research program in 2007 to develop c...
NASA Astrophysics Data System (ADS)
Satoh, Hitoshi; Niki, Noboru; Mori, Kiyoshi; Eguchi, Kenji; Kaneko, Masahiro; Kakinuma, Ryutarou; Moriyama, Noriyuki; Ohmatsu, Hironobu; Masuda, Hideo; Machida, Suguru; Sasagawa, Michizou
2006-03-01
Multi-helical CT scanner advanced remarkably at the speed at which the chest CT images were acquired for mass screening. Mass screening based on multi-helical CT images requires a considerable number of images to be read. It is this time-consuming step that makes the use of helical CT for mass screening impractical at present. To overcome this problem, we have provided diagnostic assistance methods to medical screening specialists by developing a lung cancer screening algorithm that automatically detects suspected lung cancers in helical CT images and a coronary artery calcification screening algorithm that automatically detects suspected coronary artery calcification. We also have developed electronic medical recording system and prototype internet system for the community health in two or more regions by using the Virtual Private Network router and Biometric fingerprint authentication system and Biometric face authentication system for safety of medical information. Based on these diagnostic assistance methods, we have now developed a new computer-aided workstation and database that can display suspected lesions three-dimensionally in a short time. This paper describes basic studies that have been conducted to evaluate this new system. The results of this study indicate that our computer-aided diagnosis workstation and network system can increase diagnostic speed, diagnostic accuracy and safety of medical information.
NASA Technical Reports Server (NTRS)
Jeevarajan, Judith
2009-01-01
This slide presentation reviews the method developed by the NASA Johnson Space Center (JSC) to determine tolerances to internal shorts and screening for problems in commercial off the shelf (COTS) Lithium-ion batteries. The test apparatus is shown and several examples of the usage and results of the test are discussed.
Efficient and accurate adverse outcome pathway (AOP) based high-throughput screening (HTS) methods use a systems biology based approach to computationally model in vitro cellular and molecular data for rapid chemical prioritization; however, not all HTS assays are grounded by rel...
Current issues and future perspectives of gastric cancer screening
Hamashima, Chisato
2014-01-01
Gastric cancer remains the second leading cause of cancer death worldwide. About half of the incidence of gastric cancer is observed in East Asian countries, which show a higher mortality than other countries. The effectiveness of 3 new gastric cancer screening techniques, namely, upper gastrointestinal endoscopy, serological testing, and “screen and treat” method were extensively reviewed. Moreover, the phases of development for cancer screening were analyzed on the basis of the biomarker development road map. Several observational studies have reported the effectiveness of endoscopic screening in reducing mortality from gastric cancer. On the other hand, serologic testing has mainly been used for targeting the high-risk group for gastric cancer. To date, the effectiveness of new techniques for gastric cancer screening has remained limited. However, endoscopic screening is presently in the last trial phase of development before their introduction to population-based screening. To effectively introduce new techniques for gastric cancer screening in a community, incidence and mortality reduction from gastric cancer must be initially and thoroughly evaluated by conducting reliable studies. In addition to effectiveness evaluation, the balance of benefits and harms must be carefully assessed before introducing these new techniques for population-based screening. PMID:25320514
Reiman, Anne; Pandey, Sarojini; Lloyd, Kate L; Dyer, Nigel; Khan, Mike; Crockard, Martin; Latten, Mark J; Watson, Tracey L; Cree, Ian A; Grammatopoulos, Dimitris K
2016-11-01
Background Detection of disease-associated mutations in patients with familial hypercholesterolaemia is crucial for early interventions to reduce risk of cardiovascular disease. Screening for these mutations represents a methodological challenge since more than 1200 different causal mutations in the low-density lipoprotein receptor has been identified. A number of methodological approaches have been developed for screening by clinical diagnostic laboratories. Methods Using primers targeting, the low-density lipoprotein receptor, apolipoprotein B, and proprotein convertase subtilisin/kexin type 9, we developed a novel Ion Torrent-based targeted re-sequencing method. We validated this in a West Midlands-UK small cohort of 58 patients screened in parallel with other mutation-targeting methods, such as multiplex polymerase chain reaction (Elucigene FH20), oligonucleotide arrays (Randox familial hypercholesterolaemia array) or the Illumina next-generation sequencing platform. Results In this small cohort, the next-generation sequencing method achieved excellent analytical performance characteristics and showed 100% and 89% concordance with the Randox array and the Elucigene FH20 assay. Investigation of the discrepant results identified two cases of mutation misclassification of the Elucigene FH20 multiplex polymerase chain reaction assay. A number of novel mutations not previously reported were also identified by the next-generation sequencing method. Conclusions Ion Torrent-based next-generation sequencing can deliver a suitable alternative for the molecular investigation of familial hypercholesterolaemia patients, especially when comprehensive mutation screening for rare or unknown mutations is required.
2014-01-01
Background Cervical cancer poses a significant threat to Korean American women, who are reported to have one of the highest cervical cancer mortality rates in the United States. Studies consistently report that Korean American women have the lowest Pap test screening rates across US ethnic groups. Objective In response to the need to enhance cervical cancer screening in this vulnerable population, we developed and tested a 7-day mobile phone text message-based cervical cancer Screening (mScreening) intervention designed to promote the receipt of Pap tests by young Korean American women. Methods We developed and assessed the acceptability and feasibility of a 1-week mScreening intervention to increase knowledge of cervical cancer screening, intent to receive screening, and the receipt of a Pap test. Fogg’s Behavior Model was the conceptual framework that guided the development of the mScreening intervention. A series of focus groups were conducted to inform the development of the intervention. The messages were individually tailored for each participant and delivered to them for a 7-day period at each participant’s preferred time. A quasi-experimental research design of 30 Korean American women aged 21 to 29 years was utilized with baseline, post (1 week after the completion of mScreening), and follow-up (3 months after the completion of mScreening) testing. Results Findings revealed a significant increase in participants’ knowledge of cervical cancer (P<.001) and guidelines for cervical cancer screening (P=.006). A total of 23% (7/30) (95% CI 9.9-42.3) of the mScreening participants received a Pap test; 83% (25/30) of the participants expressed satisfaction with the intervention and 97% (29/30) reported that they would recommend the program to their friends, indicating excellent acceptability and feasibility of the intervention. Conclusions This study provides evidence of the effectiveness and feasibility of the mScreening intervention. Mobile technology is a promising tool to increase both knowledge and receipt of cervical cancer screening. Given the widespread usage of mobile phones among young adults, a mobile phone-based health intervention could be a low-cost and effective method of reaching populations with low cervical cancer screening rates, using individually tailored messages that cover broad content areas and overcome restrictions to place and time of delivery. PMID:25164545
Varughese, Anna M; Hagerman, Nancy; Townsend, Mari E
2013-07-01
The anesthesia preoperative screening and evaluation of a patient prior to surgery is a critical element in the safe and effective delivery of anesthesia care. In this era of increased focus on cost containment, many anesthesia practices are looking for ways to maximize productivity while maintaining the quality of the preoperative evaluation process by harnessing and optimizing all available resources. We sought to develop a Nurse Practitioner-assisted Preoperative Anesthesia Screening process using quality improvement methods with the goal of maintaining the quality of the screening process, while at the same time redirecting anesthesiologists time for the provision of nonoperating room (OR) anesthesia. The Nurse practitioner (NP) time (approximately 10 h per week) directed to this project was gained as a result of an earlier resource utilization improvement project within the Department of Anesthesia. The goal of this improvement project was to increase the proportion of patient anesthesia screens conducted by NPs to 50% within 6 months. After discussion with key stakeholders of the process, a multidisciplinary improvement team identified a set of operational factors (key drivers) believed to be important to the success of the preoperative anesthesia screening process. These included the development of dedicated NP time for daily screening, NP competency and confidence with the screening process, effective mentoring by anesthesiologists, standardization of screening process, and communication with stakeholders of the process, that is, surgeons. These key drivers focused on the development of several interventions such as (i) NP education in the preoperative anesthesia screening for consultation process by a series of didactic lectures conducted by anesthesiologists, and NP's shadowing an anesthesiologist during the screening process, (ii) Anesthesiologist mentoring and assessment of NP screenings using the dual screening process whereby both anesthesiologists and NP conducted the screening process independently and results were compared and discussed, (iii) Examination and re-adjustment of NP schedules to provide time for daily screening while preserving other responsibilities, and (iv) Standardization through the development of guidelines for the preoperative screening process. Measures recorded included the percentage of patient anesthesia screens conducted by NP, the percentage of dual screens with MD and NP agreement regarding the screening decision, and the average times taken for the anesthesiologist and NP screening process. After implementation of these interventions, the percentage of successful NP-assisted anesthesia consultation screenings increased from 0% to 65% over a period of 6 months. The Anesthesiologists' time redirected to non-OR anesthesia averaged at least 8 h a week. The percentage of dual screens with agreement on the screening decision was 96% (goal >95%). The overall average time taken for a NP screen was 8.2 min vs 4.5 min for an anesthesiologist screen. The overall average operating room delays and cancelations for cases on the day of surgery remained the same. By applying quality improvement methods, we identified key drivers for the institution of an NP-assisted preoperative screening process and successfully implemented this process while redirecting anesthesiologists' time for the provision of non-OR anesthesia. This project was instrumental in improving the matching of provider skills with clinical need while maintaining superior outcomes at the lowest possible cost. © 2013 John Wiley & Sons Ltd.
Hearing Screening Follow-Up: Completing the Process to Identify Hearing Health Needs
ERIC Educational Resources Information Center
Eiserman, William; Shisler, Lenore; Hoffman, Jeff
2015-01-01
Hearing is at the heart of language development and school readiness; increasing numbers of Early Head Start programs have come to rely on otoacoustic emissions (OAE) technology to screen all infants and toddlers for hearing loss. Successful identification of hearing health needs is dependent not only on an appropriate screening method, but also…
Chang, Yi-Pin; Chu, Yen-Ho
2014-05-16
The design, synthesis and screening of diversity-oriented peptide libraries using a "libraries from libraries" strategy for the development of inhibitors of α1-antitrypsin deficiency are described. The major buttress of the biochemical approach presented here is the use of well-established solid-phase split-and-mix method for the generation of mixture-based libraries. The combinatorial technique iterative deconvolution was employed for library screening. While molecular diversity is the general consideration of combinatorial libraries, exquisite design through systematic screening of small individual libraries is a prerequisite for effective library screening and can avoid potential problems in some cases. This review will also illustrate how large peptide libraries were designed, as well as how a conformation-sensitive assay was developed based on the mechanism of the conformational disease. Finally, the combinatorially selected peptide inhibitor capable of blocking abnormal protein aggregation will be characterized by biophysical, cellular and computational methods.
Quantum probability ranking principle for ligand-based virtual screening.
Al-Dabbagh, Mohammed Mumtaz; Salim, Naomie; Himmat, Mubarak; Ahmed, Ali; Saeed, Faisal
2017-04-01
Chemical libraries contain thousands of compounds that need screening, which increases the need for computational methods that can rank or prioritize compounds. The tools of virtual screening are widely exploited to enhance the cost effectiveness of lead drug discovery programs by ranking chemical compounds databases in decreasing probability of biological activity based upon probability ranking principle (PRP). In this paper, we developed a novel ranking approach for molecular compounds inspired by quantum mechanics, called quantum probability ranking principle (QPRP). The QPRP ranking criteria would make an attempt to draw an analogy between the physical experiment and molecular structure ranking process for 2D fingerprints in ligand based virtual screening (LBVS). The development of QPRP criteria in LBVS has employed the concepts of quantum at three different levels, firstly at representation level, this model makes an effort to develop a new framework of molecular representation by connecting the molecular compounds with mathematical quantum space. Secondly, estimate the similarity between chemical libraries and references based on quantum-based similarity searching method. Finally, rank the molecules using QPRP approach. Simulated virtual screening experiments with MDL drug data report (MDDR) data sets showed that QPRP outperformed the classical ranking principle (PRP) for molecular chemical compounds.
Quantum probability ranking principle for ligand-based virtual screening
NASA Astrophysics Data System (ADS)
Al-Dabbagh, Mohammed Mumtaz; Salim, Naomie; Himmat, Mubarak; Ahmed, Ali; Saeed, Faisal
2017-04-01
Chemical libraries contain thousands of compounds that need screening, which increases the need for computational methods that can rank or prioritize compounds. The tools of virtual screening are widely exploited to enhance the cost effectiveness of lead drug discovery programs by ranking chemical compounds databases in decreasing probability of biological activity based upon probability ranking principle (PRP). In this paper, we developed a novel ranking approach for molecular compounds inspired by quantum mechanics, called quantum probability ranking principle (QPRP). The QPRP ranking criteria would make an attempt to draw an analogy between the physical experiment and molecular structure ranking process for 2D fingerprints in ligand based virtual screening (LBVS). The development of QPRP criteria in LBVS has employed the concepts of quantum at three different levels, firstly at representation level, this model makes an effort to develop a new framework of molecular representation by connecting the molecular compounds with mathematical quantum space. Secondly, estimate the similarity between chemical libraries and references based on quantum-based similarity searching method. Finally, rank the molecules using QPRP approach. Simulated virtual screening experiments with MDL drug data report (MDDR) data sets showed that QPRP outperformed the classical ranking principle (PRP) for molecular chemical compounds.
A simple and rapid radiochemical choline acetyltransferase (ChAT) assay screening test.
Shiba, Kazuhiro; Ogawa, Kazuma; Kinuya, Seigo; Yajima, Kazuyoshi; Mori, Hirofumi
2006-10-15
A simple radiochemical choline acetyltransferase (ChAT) assay screening test was developed by measuring for [(3)H]acetylcholine ([(3)H]ACh) formed from 0.2 mM [(3)H]acetyl-coenzyme A ([(3)H]acetyl-CoA) and 1 mM choline by 0.2 mg of rat brain homogenates containing ChAT into 96-well microplates. A simple and rapid procedure for isolating [(3)H]ACh from the incubation mixture into 96-well microplates was achieved by using a sodium tetraphenylboron (Kalibor) solution (in ethyl acetate, 0.75%, w/v) and a hydrophobic liquid scintillator mixture (1:5, v/v, 0.2 mL) as an extraction solvent. The benefits of this radiochemical method using 96-well microplates are as follows: (1) this method is reliable and reproducible; (2) many samples can be examined at the same time by this method; (3) this method is economical and effective in reducing radioactive waste. The development of a new simple radiochemical ChAT assay screening test is the first stage of development of radiolabeled ChAT mapping agent.
Zhou, Hang; Xiang, Qunying; Hu, Ting; Zhang, Qinghua; Chen, Zhilan; Ma, Ding; Feng, Ling
2013-01-01
Purpose Cervical cancer screening is an effective method for reducing the incidence and mortality of cervical cancer, but the screening attendance rate in developing countries is far from satisfactory, especially in rural areas. Wufeng is a region of high cervical cancer incidence in China. This study aimed to investigate the issues that concern cervical cancer and screening and the factors that affect women’s willingness to undergo cervical cancer screening in the Wufeng area. Participants and Methods A cross-sectional survey of women was conducted to determine their knowledge about cervical cancer and screening, demographic characteristics and the barriers to screening. Results Women who were willing to undergo screenings had higher knowledge levels. “Anxious feeling once the disease was diagnosed” (47.6%), “No symptoms/discomfort” (34.1%) and “Do not know the benefits of cervical cancer screening” (13.4%) were the top three reasons for refusing cervical cancer screening. Women who were younger than 45 years old or who had lower incomes, positive family histories of cancer, secondary or higher levels of education, higher levels of knowledge and fewer barriers to screening were more willing to participate in cervical cancer screenings than women without these characteristics. Conclusion Efforts are needed to increase women’s knowledge about cervical cancer, especially the screening methods, and to improve their perceptions of the screening process for early detection to reduce cervical cancer incidence and mortality rates. PMID:23843976
Yamada, H; Ikeda-Wada, S; Oguri, K
1998-07-01
A new screening method for amphetamines was developed. It consists of derivatization with dansyl chloride, extraction of the derivative using a Sep-Pak C18 or a Bond Elut C18, solid phase extraction columns, and visualization of the fluorescence of the cartridge. A control test using drug-free urine showed no fluorescence. Amphetamine, methamphetamine and the methylenedioxy derivatives exhibited strong fluorescence, while related compounds, such as N-ethylamphetamine and fenetylline, were negative or weakly positive. The disadvantage of the present method is that it is a multi-step procedure and 20-30 min is required for screening. However, since it has a different specificity from the widely used immunochemical technique, it is suggested to be a useful screen for amphetamines.
Zhang, Haomin; Guo, Yinan; Meng, Lingwen; Sun, Hui; Yang, Yinping; Gao, Ying; Sun, Jiaming
2018-01-01
Background: At present, approximately 17–25 million people in the world suffer from Alzheimer's disease (AD). The most efficacious and acceptable therapeutic drug clinically are the acetylcholinesterase inhibitors (AChEIs). Yinhuang oral liquid is a Chinese medicine preparation which contains AChEIs according to the literatures. However, no strategy has been presented for rapid screening and identification of AChEIs from Yinhuang oral liquid. Objective: To develop a method for rapid screening and identification of AChEIs from Yinhuang oral liquid using ultrafiltration–liquid chromatography–electrospray ionization tandem mass spectrometry (UF-LC-ESI-MS/MS). Materials and Methods: In this study, UF incubation conditions such as enzyme concentration, incubation time, and incubation temperature were optimized so as to get better screening results. The AChEIs from Yinhuang oral liquid were identified by high-performance liquid chromatography-ESI-MS and the improved Ellman method was used for the AChE inhibitory activity test in vitro. Results: The results showed that Yinhuang oral liquid can inhibit the activity of AChE. We screened and identified seven compounds with potential AChE inhibitory activity from Yinhuang oral liquid, which provided experimental basis for the treatment and prevention of AD. Conclusion: The current technique was used to directly screen the active ingredients with acetylcholinesterase inhibition from complex traditional Chinese medicine, which was simple, rapid, accurate, and suitable for high-throughput screening of AChEI from complex systems. SUMMARY A UF-LC-ESI-MS/MS method for rapid screening and identification of AChEIs from Yinhuang oral liquid was developedSeven compounds were screened and identified with potential AChE inhibitory activity from Yinhuang oral liquidIt provided experimental basis of Yinhuang oral liquid for the treating and preventing AD. Abbreviations used: (AD): Alzheimer's disease; (UF-LC-ESI-MS/MS): ultrafiltration–liquid chromatography–electrospray ionization tandem mass spectrometry; (AChEIs): acetylcholinesterase inhibitors. PMID:29720840
Cullerton, Katherine; Gallegos, Danielle; Ashley, Ella; Do, Hong; Voloschenko, Anna; Fleming, MaryLou; Ramsey, Rebecca; Gould, Trish
2016-06-29
Issue addressed: Screening for cancer of the cervix, breast and bowel can reduce morbidity and mortality. Low participation rates in cancer screening have been identified among migrant communities internationally. Attempting to improve low rates of cancer screening, the Ethnic Communities Council of Queensland developed a pilot Cancer Screening Education Program for breast, bowel and cervical cancer. This study determines the impact of education sessions on knowledge, attitudes and intentions to participate in screening for culturally and linguistically diverse (CALD) communities living in Brisbane, Queensland. Methods: Seven CALD groups (Arabic-speaking, Bosnian, South Asian (including Indian and Bhutanese), Samoan and Pacific Island, Spanish-speaking, Sudanese and Vietnamese) participated in a culturally-tailored cancer screening education pilot program that was developed using the Health Belief Model. A pre- and post-education evaluation session measured changes in knowledge, attitudes and intention related to breast, bowel and cervical cancer and screening. The evaluation focussed on perceived susceptibility, perceived seriousness and the target population's beliefs about reducing risk by cancer screening. Results: There were 159 participants in the three cancer screening education sessions. Overall participants' knowledge increased, some attitudes toward participation in cancer screening became more positive and intent to participate in future screening increased (n=146). Conclusion: These results indicate the importance of developing screening approaches that address the barriers to participation among CALD communities and that a culturally-tailored education program is effective in improving knowledge, attitudes about and intentions to participate in cancer screening. So what?: It is important that culturally-tailored programs are developed in conjunction with communities to improve health outcomes.
Directed evolution: tailoring biocatalysts for industrial applications.
Kumar, Ashwani; Singh, Suren
2013-12-01
Current challenges and promises of white biotechnology encourage protein engineers to use a directed evolution approach to generate novel and useful biocatalysts for various sets of applications. Different methods of enzyme engineering have been used in the past in an attempt to produce enzymes with improved functions and properties. Recent advancement in the field of random mutagenesis, screening, selection and computational design increased the versatility and the rapid development of enzymes under strong selection pressure with directed evolution experiments. Techniques of directed evolution improve enzymes fitness without understanding them in great detail and clearly demonstrate its future role in adapting enzymes for use in industry. Despite significant advances to date regarding biocatalyst improvement, there still remains a need to improve mutagenesis strategies and development of easy screening and selection tools without significant human intervention. This review covers fundamental and major development of directed evolution techniques, and highlights the advances in mutagenesis, screening and selection methods with examples of enzymes developed by using these approaches. Several commonly used methods for creating molecular diversity with their advantages and disadvantages including some recently used strategies are also discussed.
Predictors of Cervical Cancer Screening for Rarely or Never Screened Rural Appalachian Women
Hatcher, Jennifer; Studts, Christina R.; Dignan, Mark; Turner, Lisa M.; Schoenberg, Nancy E.
2011-01-01
Background and Purpose Women who have not had a Papanicolaou test in five years or more have increased risk of developing invasive cervical cancer. This study compares Appalachian women whose last screening was more than one year ago but less than five years ago with those not screened for the previous five years or more. Methods Using PRECEDE/PROCEED as a guide, factors related to obtaining Pap tests were examined using cross-sectional data from 345 Appalachian Kentucky women. Bivariate and multivariate analyses were conducted to identify predictors of screening. Results Thirty-four percent of participants were rarely- or never-screened. In multiple logistic regression analyses, several factors increased those odds, including belief that cervical cancer has symptoms, and not having a regular source of medical care. Conclusion The findings from this study may lead to the development of effective intervention and policies that increase cervical cancer screening in this population. PMID:21317514
Barriers and facilitators to health screening in men: A systematic review.
Teo, Chin Hai; Ng, Chirk Jenn; Booth, Andrew; White, Alan
2016-09-01
Men have poorer health status and are less likely to attend health screening compared to women. This systematic review presents current evidence on the barriers and facilitators to engaging men in health screening. We included qualitative, quantitative and mixed-method studies identified through five electronic databases, contact with experts and reference mining. Two researchers selected and appraised the studies independently. Data extraction and synthesis were conducted using the 'best fit' framework synthesis method. 53 qualitative, 44 quantitative and 6 mixed-method studies were included. Factors influencing health screening uptake in men can be categorized into five domains: individual, social, health system, healthcare professional and screening procedure. The most commonly reported barriers are fear of getting the disease and low risk perception; for facilitators, they are perceived risk and benefits of screening. Male-dominant barriers include heterosexual -self-presentation, avoidance of femininity and lack of time. The partner's role is the most common male-dominant facilitator to screening. This systematic review provides a comprehensive overview of barriers and facilitators to health screening in men including the male-dominant factors. The findings are particularly useful for clinicians, researchers and policy makers who are developing interventions and policies to increase screening uptake in men. Copyright © 2016 Elsevier Ltd. All rights reserved.
Iversen, Carol; Druggan, Patrick; Schumacher, Sandra; Lehner, Angelika; Feer, Claudia; Gschwend, Karl; Joosten, Han; Stephan, Roger
2008-01-01
A differential medium, “Cronobacter” screening broth, has been designed to complement agars based on hydrolysis of chromogenic α-glucopyranoside substrates. The broth was evaluated using 329 Enterobacteriaceae strains (229 target isolates), spiked/naturally contaminated samples, and a parallel comparison with current methods for raw materials, line/end products, and factory environment samples. PMID:18310415
A Disposable Microfluidic Device with a Screen Printed Electrode for Mimicking Phase II Metabolism
Vasiliadou, Rafaela; Nasr Esfahani, Mohammad Mehdi; Brown, Nathan J.; Welham, Kevin J.
2016-01-01
Human metabolism is investigated using several in vitro methods. However, the current methodologies are often expensive, tedious and complicated. Over the last decade, the combination of electrochemistry (EC) with mass spectrometry (MS) has a simpler and a cheaper alternative to mimic the human metabolism. This paper describes the development of a disposable microfluidic device with a screen-printed electrode (SPE) for monitoring phase II GSH reactions. The proposed chip has the potential to be used as a primary screening tool, thus complementing the current in vitro methods. PMID:27598162
Tyrrell, A; Worrall, E; Que, T N; Bates, I
2011-06-01
To compare the cost and effectiveness of Copper Sulphate (CS) and HemoCue (HC) methods for screening blood donors for anaemia. Robust information from developing countries about cost and effectiveness of anaemia screening methods for blood donors is scarce. In such countries there are widespread shortages of blood, so the most cost-effective method should maximise blood supply without compromising donor safety. Economic data (e.g. staff time, equipment and buildings) were collected from direct observation of procedures and purchase data from Hanoi's Central Blood Bank administrative department. A framework for comparing the cost and effectiveness of anaemia screening methods was developed and a cost per effective (i.e. usable and accurate) test was generated for each method. Samples from 100 potential donors from the Hanoi Central Blood Bank (static) and 198 from two mobile units were tested. The mean probability of an ineffective anaemia test was 0·1 (0·05-0·2). The average cost of an HC test was $0·75 (static $0·61 and mobile $0·89) and a CS test was $0·31 (static $0·17 and mobile $0·45). The difference between static and mobile units was predominantly due to transport costs; the difference between the two methods was predominantly due to the HC microcuvettes. In this setting the CS yields greater value for money than the HC method for screening blood donors. The relative cost and effectiveness of CS and HC may be different in places with higher staff turnover, lower test accuracy, higher anaemia prevalence or lower workload than in Vietnam. © 2010 Liverpool School of Tropical Medicine. Transfusion Medicine © 2010 British Blood Transfusion Society.
Tracking and tracing of participants in two large cancer screening trials.
Marcus, Pamela M; Childs, Jeffery; Gahagan, Betsy; Gren, Lisa H
2012-07-01
Many clinical trials rely on participant report to first learn about study events. It is therefore important to have current contact information and the ability to locate participants should information become outdated. The Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial (PLCO) and the Lung Screening Study (LSS) component of the National Lung Screening Trial, two large randomized cancer screening trials, enrolled almost 190,000 participants on whom annual contact was necessary. Ten screening centers participated in both trials. Centers developed methods to track participants and trace them when necessary. We describe the methods used to keep track of participants and trace them when lost, and the extent to which each method was used. Screening center coordinators were asked, using a self-administered paper questionnaire, to rate the extent to which specific tracking and tracing methods were used. Many methods were used by the screening centers, including telephone calls, mail, and internet searches. The most extensively used methods involved telephoning the participant on his or her home or cell phone, or telephoning a person identified by the participant as someone who would know about the participant's whereabouts. Internet searches were used extensively as well; these included searches on names, reverse-lookup searches (on addresses or telephone numbers) and searches of the Social Security Death Index. Over time, the percentage of participants requiring tracing decreased. Telephone communication and internet services were useful in keeping track of PLCO and LSS participants and tracing them when contact information was no longer valid. Published by Elsevier Inc.
Wang, Jian; Chow, Willis; Chang, James; Wong, Jon W
2017-01-18
A semiautomated qualitative method for target screening of 448 pesticide residues in fruits and vegetables was developed and validated using ultrahigh-performance liquid chromatography coupled with electrospray ionization quadrupole Orbitrap high-resolution mass spectrometry (UHPLC/ESI Q-Orbitrap). The Q-Orbitrap Full MS/dd-MS 2 (data dependent acquisition) was used to acquire product-ion spectra of individual pesticides to build a compound database or an MS library, while its Full MS/DIA (data independent acquisition) was utilized for sample data acquisition from fruit and vegetable matrices fortified with pesticides at 10 and 100 μg/kg for target screening purpose. Accurate mass, retention time and response threshold were three key parameters in a compound database that were used to detect incurred pesticide residues in samples. The concepts and practical aspects of in-spectrum mass correction or solvent background lock-mass correction, retention time alignment and response threshold adjustment are discussed while building a functional and working compound database for target screening. The validated target screening method is capable of screening at least 94% and 99% of 448 pesticides at 10 and 100 μg/kg, respectively, in fruits and vegetables without having to evaluate every compound manually during data processing, which significantly reduced the workload in routine practice.
Diagnostic Methods for Platelet Bacteria Screening: Current Status and Developments
Störmer, Melanie; Vollmer, Tanja
2014-01-01
Summary Bacterial contamination of blood components and the prevention of transfusion-associated bacterial infection still remains a major challenge in transfusion medicine. Over the past few decades, a significant reduction in the transmission of viral infections has been achieved due to the introduction of mandatory virus screening. Platelet concentrates (PCs) represent one of the highest risks for bacterial infection. This is due to the required storage conditions for PCs in gas-permeable containers at room temperature with constant agitation, which support bacterial proliferation from low contamination levels to high titers. In contrast to virus screening, since 1997 in Germany bacterial testing of PCs is only performed as a routine quality control or, since 2008, to prolong the shelf life to 5 days. In general, bacterial screening of PCs by cultivation methods is implemented by the various blood services. Although these culturing systems will remain the gold standard, the significance of rapid methods for screening for bacterial contamination has increased over the last few years. These new methods provide powerful tools for increasing the bacterial safety of blood components. This article summarizes the course of policies and provisions introduced to increase bacterial safety of blood components in Germany. Furthermore, we give an overview of the different diagnostic methods for bacterial screening of PCs and their current applicability in routine screening processes. PMID:24659944
2013-01-01
Background Literature on scoliosis screening is vast, however because of the observational nature of available data and methodological flaws, data interpretation is often complex, leading to incomplete and sometimes, somewhat misleading conclusions. The need to propose a set of methods for critical appraisal of the literature about scoliosis screening, a comprehensive summary and rating of the available evidence appeared essential. Methods To address these gaps, the study aims were: i) To propose a framework for the assessment of published studies on scoliosis screening effectiveness; ii) To suggest specific questions to be answered on screening effectiveness instead of trying to reach a global position for or against the programs; iii) To contextualize the knowledge through expert panel consultation and meaningful recommendations. The general methodological approach proceeds through the following steps: Elaboration of the conceptual framework; Formulation of the review questions; Identification of the criteria for the review; Selection of the studies; Critical assessment of the studies; Results synthesis; Formulation and grading of recommendations in response to the questions. This plan follows at best GRADE Group (Grades of Recommendation, Assessment, Development and Evaluation) requirements for systematic reviews, assessing quality of evidence and grading the strength of recommendations. Conclusions In this article, the methods developed in support of this work are presented since they may be of some interest for similar reviews in scoliosis and orthopaedic fields. PMID:23883346
Green, Eric P; Tuli, Hawa; Kwobah, Edith; Menya, D; Chesire, Irene; Schmidt, Christina
2018-03-01
Routine screening for perinatal depression is not common in most primary health care settings. The U.S. Preventive Services Task Force only recently updated their recommendation on depression screening to specifically recommend screening during the pre- and postpartum periods. While practitioners in high-income countries can respond to this new recommendation by implementing one of several existing depression screening tools developed in Western contexts, such as the Edinburgh Postnatal Depression Scale (EPDS) or the Patient Health Questionnaire-9 (PHQ-9), these tools lack strong evidence of cross-cultural equivalence, validity for case finding, and precision in measuring response to treatment in developing countries. Thus, there is a critical need to develop and validate new screening tools for perinatal depression that can be used by lay health workers, primary health care personnel, and patients. Working in rural Kenya, we used free listing, card sorting, and item analysis methods to develop a locally-relevant screening tool that blended Western psychiatric concepts with local idioms of distress. We conducted a validation study with a random sample of 193 pregnant women and new mothers to test the diagnostic accuracy of this scale along with the EPDS and PHQ-9. The sensitivity/specificity of the EPDS and PHQ-9 was estimated to be 0.70/0.72 and 0.70/0.73, respectively. This compared to sensitivity/specificity of 0.90/0.90 for a new 9-item locally-developed tool called the Perinatal Depression Screening (PDEPS). Across these three tools, internal consistency reliability ranged from 0.77 to 0.81 and test-retest reliability ranged from 0.57 to 0.67. The prevalence of depression ranges from 5.2% to 6.2% depending on the clinical reference standard. The EPDS and PHQ-9 are valid and reliable screening tools for perinatal depression in rural Western Kenya, the PDEPS may be a more useful alternative. At less than 10%, the prevalence of depression in this region appears to be lower than other published estimates for African and other low-income countries. Copyright © 2017 Elsevier B.V. All rights reserved.
Flexible methods for segmentation evaluation: results from CT-based luggage screening.
Karimi, Seemeen; Jiang, Xiaoqian; Cosman, Pamela; Martz, Harry
2014-01-01
Imaging systems used in aviation security include segmentation algorithms in an automatic threat recognition pipeline. The segmentation algorithms evolve in response to emerging threats and changing performance requirements. Analysis of segmentation algorithms' behavior, including the nature of errors and feature recovery, facilitates their development. However, evaluation methods from the literature provide limited characterization of the segmentation algorithms. To develop segmentation evaluation methods that measure systematic errors such as oversegmentation and undersegmentation, outliers, and overall errors. The methods must measure feature recovery and allow us to prioritize segments. We developed two complementary evaluation methods using statistical techniques and information theory. We also created a semi-automatic method to define ground truth from 3D images. We applied our methods to evaluate five segmentation algorithms developed for CT luggage screening. We validated our methods with synthetic problems and an observer evaluation. Both methods selected the same best segmentation algorithm. Human evaluation confirmed the findings. The measurement of systematic errors and prioritization helped in understanding the behavior of each segmentation algorithm. Our evaluation methods allow us to measure and explain the accuracy of segmentation algorithms.
NASA Astrophysics Data System (ADS)
Satoh, Hitoshi; Niki, Noboru; Eguchi, Kenji; Moriyama, Noriyuki; Ohmatsu, Hironobu; Masuda, Hideo; Machida, Suguru
2008-03-01
Mass screening based on multi-helical CT images requires a considerable number of images to be read. It is this time-consuming step that makes the use of helical CT for mass screening impractical at present. To overcome this problem, we have provided diagnostic assistance methods to medical screening specialists by developing a lung cancer screening algorithm that automatically detects suspected lung cancers in helical CT images, a coronary artery calcification screening algorithm that automatically detects suspected coronary artery calcification and a vertebra body analysis algorithm for quantitative evaluation of osteoporosis likelihood by using helical CT scanner for the lung cancer mass screening. The function to observe suspicious shadow in detail are provided in computer-aided diagnosis workstation with these screening algorithms. We also have developed the telemedicine network by using Web medical image conference system with the security improvement of images transmission, Biometric fingerprint authentication system and Biometric face authentication system. Biometric face authentication used on site of telemedicine makes "Encryption of file" and Success in login" effective. As a result, patients' private information is protected. Based on these diagnostic assistance methods, we have developed a new computer-aided workstation and a new telemedicine network that can display suspected lesions three-dimensionally in a short time. The results of this study indicate that our radiological information system without film by using computer-aided diagnosis workstation and our telemedicine network system can increase diagnostic speed, diagnostic accuracy and security improvement of medical information.
Rapid screening of radioactivity in food for emergency response.
Bari, A; Khan, A J; Semkow, T M; Syed, U-F; Roselan, A; Haines, D K; Roth, G; West, L; Arndt, M
2011-06-01
This paper describes the development of methods for the rapid screening of gross alpha (GA) and gross beta (GB) radioactivity in liquid foods, specifically, Tang drink mix, apple juice, and milk, as well as screening of GA, GB, and gamma radioactivity from surface deposition on apples. Detailed procedures were developed for spiking of matrices with (241)Am (alpha radioactivity), (90)Sr/(90)Y (beta radioactivity), and (60)Co, (137)Cs, and (241)Am (gamma radioactivity). Matrix stability studies were performed for 43 days after spiking. The method for liquid foods is based upon rapid digestion, evaporation, and flaming, followed by gas proportional (GP) counting. For the apple matrix, surface radioactivity was acid-leached, followed by GP counting and/or gamma spectrometry. The average leaching recoveries from four different apple brands were between 63% and 96%, and have been interpreted on the basis of ion transport through the apple cuticle. The minimum detectable concentrations (MDCs) were calculated from either the background or method-blank (MB) measurements. They were found to satisfy the required U.S. FDA's Derived Intervention Levels (DILs) in all but one case. The newly developed methods can perform radioactivity screening in foods within a few hours and have the potential to capacity with further automation. They are especially applicable to emergency response following accidental or intentional contamination of food with radioactivity. Published by Elsevier Ltd.
The Evolution of the Snellen E to the Blackbird. (Blackbird Preschool Vision Screening Program).
ERIC Educational Resources Information Center
Sato-Viacrucis, Kiyo
Comparison of a variety of vision screening methods used with preschool children led to modification of the standard Snellen E test called the Blackbird Vision Screening System. An instructional story using an "E-bird" was developed to teach children the various possible positions of the E. The visual confusion caused by the chart was…
Mizutani, Miho Yamada; Itai, Akiko
2004-09-23
A method of easily finding ligands, with a variety of core structures, for a given target macromolecule would greatly contribute to the rapid identification of novel lead compounds for drug development. We have developed an efficient method for discovering ligand candidates from a number of flexible compounds included in databases, when the three-dimensional (3D) structure of the drug target is available. The method, named ADAM&EVE, makes use of our automated docking method ADAM, which has already been reported. Like ADAM, ADAM&EVE takes account of the flexibility of each molecule in databases, by exploring the conformational space fully and continuously. Database screening has been made much faster than with ADAM through the tuning of parameters, so that computational screening of several hundred thousand compounds is possible in a practical time. Promising ligand candidates can be selected according to various criteria based on the docking results and characteristics of compounds. Furthermore, we have developed a new tool, EVE-MAKE, for automatically preparing the additional compound data necessary for flexible docking calculation, prior to 3D database screening. Among several successful cases of lead discovery by ADAM&EVE, the finding of novel acetylcholinesterase (AChE) inhibitors is presented here. We performed a virtual screening of about 160 000 commercially available compounds against the X-ray crystallographic structure of AChE. Among 114 compounds that could be purchased and assayed, 35 molecules with various core structures showed inhibitory activities with IC(50) values less than 100 microM. Thirteen compounds had IC(50) values between 0.5 and 10 microM, and almost all their core structures are very different from those of known inhibitors. The results demonstrate the effectiveness and validity of the ADAM&EVE approach and provide a starting point for development of novel drugs to treat Alzheimer's disease.
Thin-Film Thermoelectric Module for Power Generator Applications Using a Screen-Printing Method
NASA Astrophysics Data System (ADS)
Lee, Heon-Bok; Yang, Hyun Jeong; We, Ju Hyung; Kim, Kukjoo; Choi, Kyung Cheol; Cho, Byung Jin
2011-05-01
A new process for fabricating a low-cost thermoelectric module using a screen-printing method has been developed. Thermoelectric properties of screen-printed ZnSb films were investigated in an effort to develop a thermoelectric module with low cost per watt. The screen-printed Zn x Sb1- x films showed a low carrier concentration and high Seebeck coefficient when x was in the range of 0.5 to 0.57 and the annealing temperature was kept below 550°C. When the annealing temperature was higher than 550°C, the carrier concentration of the Zn x Sb1- x films reached that of a metal, leading to a decrease of the Seebeck coefficient. In the present experiment, the optimized carrier concentration of screen-printed ZnSb was 7 × 1018/cm3. The output voltage and power density of the ZnSb film were 10 mV and 0.17 mW/cm2, respectively, at Δ T = 50 K. A thermoelectric module was produced using the proposed screen-printing approach with ZnSb and CoSb3 as p-type and n-type thermoelectric materials, respectively, and copper as the pad metal.
Akinyemiju, Tomi F.
2012-01-01
Background Breast and Cervical cancer are the two most common cancers among women in developing countries. Regular screening is the most effective way of ensuring that these cancers are detected at early stages; however few studies have assessed factors that predict cancer screening in developing countries. Purpose To assess the influence of household socio-economic status (SES), healthcare access and country level characteristics on breast and cervical cancer screening among women in developing countries. Methods Women ages 18–69 years (cervical cancer screening) and 40–69 years (breast cancer screening) from 15 developing countries who participated in the 2003 World Health Survey provided data for this study. Household SES and healthcare access was assessed based on self-reported survey responses. SAS survey procedures (SAS, Version 9.2) were used to assess determinants of breast and cervical cancer screening in separate models. Results 4.1% of women ages 18–69 years had received cervical cancer screening in the past three years, while only 2.2% of women ages 40–69 years had received breast cancer screening in the past 5 years in developing countries. Cancer screening rates varied by country; cervical cancer screening ranged from 1.1% in Bangladesh to 57.6% in Congo and breast cancer screening ranged from 0% in Mali to 26% in Congo. Significant determinants of cancer screening were household SES, rural residence, country health expenditure (as a percent of GDP) as well as healthcare access. Discussion A lot more needs to be done to improve screening rates for breast and cervical cancer in developing countries, such as increasing health expenditure (especially in rural areas), applying the increased funds towards the provision of more, better educated health providers as well as improved infrastructure. PMID:23155413
Fragment Screening and HIV Therapeutics
Bauman, Joseph D.; Patel, Disha; Arnold, Eddy
2013-01-01
Fragment screening has proven to be a powerful alternative to traditional methods for drug discovery. Biophysical methods, such as X-ray crystallography, NMR spectroscopy, and surface plasmon resonance, are used to screen a diverse library of small molecule compounds. Although compounds identified via this approach have relatively weak affinity, they provide a good platform for lead development and are highly efficient binders with respect to their size. Fragment screening has been utilized for a wide-range of targets, including HIV-1 proteins. Here, we review the fragment screening studies targeting HIV-1 proteins using X-ray crystallography or surface plasmon resonance. These studies have successfully detected binding of novel fragments to either previously established or new sites on HIV-1 protease and reverse transcriptase. In addition, fragment screening against HIV-1 reverse transcriptase has been used as a tool to better understand the complex nature of ligand binding to a flexible target. PMID:21972022
Katz, Mira L.; Heaner, Sarah; Reiter, Paul; van Putten, Julie; Murray, Lee; McDougle, Leon; Cegala, Donald J.; Post, Douglas; David, Prabu; Slater, Michael; Paskett, Electra D.
2009-01-01
Background Low rates of colorectal cancer (CRC) screening persist due to individual, provider and system level barriers. Purpose To develop and obtain initial feedback about a CRC screening educational video from community members and medical professionals. Methods Focus groups of patients were conducted prior to the development of an educational video and focus groups of patients provided initial feedback about the developed CRC screening educational video. Medical personnel reviewed the video and made recommendations prior to final editing of the video. Results Patients identified CRC screening barriers and made suggestions about the information to include in the educational video. Their suggestions included using a healthcare provider to state the importance of completing CRC screening, demonstrate how to complete the fecal occult blood test, and that men and women from diverse ethnic groups and races could be included in the same video. Participants reviewed the developed video and mentioned that their suggestions were portrayed correctly, the video was culturally appropriate, and the information presented in the video was easy to understand. Medical personnel made suggestions on ways to improve the content and the delivery of the medical information prior to final editing of the video. Discussion Participants provided valuable information in the development of an educational video to improve patient knowledge and patient-provider communication about CRC screening. The educational video developed was based on the Protection Motivation Theory and addressed the colon cancer screening barriers identified in this mostly minority and low-income patient population. Future research will determine if CRC screening increases among patients who watch the educational video. Translation to Health Education Practice Educational videos can provide important information about CRC and CRC screening to average-risk adults. PMID:20209024
Patients’ perceptions of oral cancer screening in dental practice: a cross-sectional study
2012-01-01
Background Oral cancer is increasing in incidence in the UK and indeed worldwide. Delay in diagnosis is common; up to half of patients are diagnosed with advanced lesions. Thus it is essential to develop methods to aid early detection. This study aimed to assess dental patients’ experiences and awareness of oral cancer and screening within general dental practice. Methods A cross-sectional questionnaire survey of 184 English-speaking adults, with no previous history of oral cancer was conducted. The questionnaire collected data on participant’s knowledge of oral cancer, experience of ‘screening’, attitudes and feelings towards having a screening, anticipated help-seeking behaviours, health-related behaviours (particularly risk factors) and sociodemographics. Results Twenty percent of respondents had never heard of oral cancer; 77% knew little or nothing about it and 72% did not know that their Dentist routinely screens for oral cancer. Overall, attitudes to screening were positive. Ninety two percent of respondents would like their Dentist to tell them if they were being screened for signs of oral cancer and 97% would like help from their Dentists to reduce their risk. Conclusion Patients seem generally unaware of oral cancer screening by their dentist but are happy to take part in screening, would like to be informed, and welcome the support of their Dentist to reduce their risk of developing oral cancer. PMID:23249393
Ethical issues related to screening for preeclampsia.
Jørgensen, Jennifer M; Hedley, Paula L; Gjerris, Mickey; Christiansen, Michael
2014-09-01
The implementation of new methods of treating and preventing disease raises many question of both technical and moral character. Currently, many studies focus on developing a screening test for preeclampsia (PE), a disease complicating 2-8% of pregnancies, potentially causing severe consequences for pregnant women and their fetuses. The purpose is to develop a test that can identify pregnancies at high risk for developing PE sufficiently early in pregnancy to allow for prophylaxis. However, the question of implementing a screening test for PE does not only involve an evaluation of technical feasibility and clinical efficacy, it also requires an analysis of how the test influences the conditions and choices for those tested. This study evaluates state-of-the-art techniques for preeclampsia screening in an ethical framework, pointing out the central areas of moral relevance within the context of such screening activity. Furthermore, we propose ethical guidelines that a screening programme for PE should meet in order to become an uncontroversial addition to prenatal health care. © 2012 John Wiley & Sons Ltd.
NASA Astrophysics Data System (ADS)
Deka, Jashmini; Mojumdar, Aditya; Parisse, Pietro; Onesti, Silvia; Casalis, Loredana
2017-03-01
Helicase are essential enzymes which are widespread in all life-forms. Due to their central role in nucleic acid metabolism, they are emerging as important targets for anti-viral, antibacterial and anti-cancer drugs. The development of easy, cheap, fast and robust biochemical assays to measure helicase activity, overcoming the limitations of the current methods, is a pre-requisite for the discovery of helicase inhibitors through high-throughput screenings. We have developed a method which exploits the optical properties of DNA-conjugated gold nanoparticles (AuNP) and meets the required criteria. The method was tested with the catalytic domain of the human RecQ4 helicase and compared with a conventional FRET-based assay. The AuNP-based assay produced similar results but is simpler, more robust and cheaper than FRET. Therefore, our nanotechnology-based platform shows the potential to provide a useful alternative to the existing conventional methods for following helicase activity and to screen small-molecule libraries as potential helicase inhibitors.
Choudhry, Priya
2016-01-01
Counting cells and colonies is an integral part of high-throughput screens and quantitative cellular assays. Due to its subjective and time-intensive nature, manual counting has hindered the adoption of cellular assays such as tumor spheroid formation in high-throughput screens. The objective of this study was to develop an automated method for quick and reliable counting of cells and colonies from digital images. For this purpose, I developed an ImageJ macro Cell Colony Edge and a CellProfiler Pipeline Cell Colony Counting, and compared them to other open-source digital methods and manual counts. The ImageJ macro Cell Colony Edge is valuable in counting cells and colonies, and measuring their area, volume, morphology, and intensity. In this study, I demonstrate that Cell Colony Edge is superior to other open-source methods, in speed, accuracy and applicability to diverse cellular assays. It can fulfill the need to automate colony/cell counting in high-throughput screens, colony forming assays, and cellular assays. PMID:26848849
Lung Cancer Screening Participation: Developing a Conceptual Model to Guide Research
Carter-Harris, Lisa; Davis, Lorie L.; Rawl, Susan M.
2017-01-01
Purpose To describe the development of a conceptual model to guide research focused on lung cancer screening participation from the perspective of the individual in the decision-making process. Methods Based on a comprehensive review of empirical and theoretical literature, a conceptual model was developed linking key psychological variables (stigma, medical mistrust, fatalism, worry, and fear) to the health belief model and precaution adoption process model. Results Proposed model concepts have been examined in prior research of either lung or other cancer screening behavior. To date, a few studies have explored a limited number of variables that influence screening behavior in lung cancer specifically. Therefore, relationships among concepts in the model have been proposed and future research directions presented. Conclusion This proposed model is an initial step to support theoretically based research. As lung cancer screening becomes more widely implemented, it is critical to theoretically guide research to understand variables that may be associated with lung cancer screening participation. Findings from future research guided by the proposed conceptual model can be used to refine the model and inform tailored intervention development. PMID:28304262
Development and Validation of an Automated High-Throughput System for Zebrafish In Vivo Screenings
Virto, Juan M.; Holgado, Olaia; Diez, Maria; Izpisua Belmonte, Juan Carlos; Callol-Massot, Carles
2012-01-01
The zebrafish is a vertebrate model compatible with the paradigms of drug discovery. The small size and transparency of zebrafish embryos make them amenable for the automation necessary in high-throughput screenings. We have developed an automated high-throughput platform for in vivo chemical screenings on zebrafish embryos that includes automated methods for embryo dispensation, compound delivery, incubation, imaging and analysis of the results. At present, two different assays to detect cardiotoxic compounds and angiogenesis inhibitors can be automatically run in the platform, showing the versatility of the system. A validation of these two assays with known positive and negative compounds, as well as a screening for the detection of unknown anti-angiogenic compounds, have been successfully carried out in the system developed. We present a totally automated platform that allows for high-throughput screenings in a vertebrate organism. PMID:22615792
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shattan, Michael; Stowe, Ashley; McIntosh, Kathryn
Explore feasibility of portable LIBS and micro-XRF systems as methods of field screening for real debris; Develop a LIBS Capability to rapidly screen beads for production quality control; Complete 3D elemental mapping of surrogate debris to determine uranium and other elemental migration patterns during debris formation
A rational approach to heavy-atom derivative screening
DOE Office of Scientific and Technical Information (OSTI.GOV)
Joyce, M. Gordon; Radaev, Sergei; Sun, Peter D., E-mail: psun@nih.gov
2010-04-01
In order to overcome the difficulties associated with the ‘classical’ heavy-atom derivatization procedure, an attempt has been made to develop a rational crystal-free heavy-atom-derivative screening method and a quick-soak derivatization procedure which allows heavy-atom compound identification. Despite the development in recent times of a range of techniques for phasing macromolecules, the conventional heavy-atom derivatization method still plays a significant role in protein structure determination. However, this method has become less popular in modern high-throughput oriented crystallography, mostly owing to its trial-and-error nature, which often results in lengthy empirical searches requiring large numbers of well diffracting crystals. In addition, the phasingmore » power of heavy-atom derivatives is often compromised by lack of isomorphism or even loss of diffraction. In order to overcome the difficulties associated with the ‘classical’ heavy-atom derivatization procedure, an attempt has been made to develop a rational crystal-free heavy-atom derivative-screening method and a quick-soak derivatization procedure which allows heavy-atom compound identification. The method includes three basic steps: (i) the selection of likely reactive compounds for a given protein and specific crystallization conditions based on pre-defined heavy-atom compound reactivity profiles, (ii) screening of the chosen heavy-atom compounds for their ability to form protein adducts using mass spectrometry and (iii) derivatization of crystals with selected heavy-metal compounds using the quick-soak method to maximize diffraction quality and minimize non-isomorphism. Overall, this system streamlines the process of heavy-atom compound identification and minimizes the problem of non-isomorphism in phasing.« less
New multiplex PCR methods for rapid screening of genetically modified organisms in foods
Datukishvili, Nelly; Kutateladze, Tamara; Gabriadze, Inga; Bitskinashvili, Kakha; Vishnepolsky, Boris
2015-01-01
We present novel multiplex PCR methods for rapid and reliable screening of genetically modified organisms (GMOs). New designed PCR primers targeting four frequently used GMO specific sequences permitted identification of new DNA markers, in particular 141 bp fragment of cauliflower mosaic virus (CaMV) 35S promoter, 224 bp fragment of Agrobacterium tumefaciens nopaline synthase (NOS) terminator, 256 bp fragment of 5-enolppyruvylshikimate-phosphate synthase (epsps) gene and 258 bp fragment of Cry1Ab delta-endotoxin (cry1Ab) gene for GMO screening. The certified reference materials containing Roundup Ready soybean (RRS) and maize MON 810 were applied for the development and optimization of uniplex and multiplex PCR systems. Evaluation of amplification products by agarose gel electrophoresis using negative and positive controls confirmed high specificity and sensitivity at 0.1% GMO for both RRS and MON 810. The fourplex PCR was developed and optimized that allows simultaneous detection of three common transgenic elements, such as: CaMV 35S promoter, NOS terminator, epsps gene together with soybean-specific lectin gene. The triplex PCR developed enables simultaneous identification of transgenic elements, such as: 35S promoter and cry1Ab gene together with maize zein gene. The analysis of different processed foods demonstrated that multiplex PCR methods developed in this study are useful for accurate and fast screening of GM food products. PMID:26257724
New multiplex PCR methods for rapid screening of genetically modified organisms in foods.
Datukishvili, Nelly; Kutateladze, Tamara; Gabriadze, Inga; Bitskinashvili, Kakha; Vishnepolsky, Boris
2015-01-01
We present novel multiplex PCR methods for rapid and reliable screening of genetically modified organisms (GMOs). New designed PCR primers targeting four frequently used GMO specific sequences permitted identification of new DNA markers, in particular 141 bp fragment of cauliflower mosaic virus (CaMV) 35S promoter, 224 bp fragment of Agrobacterium tumefaciens nopaline synthase (NOS) terminator, 256 bp fragment of 5-enolppyruvylshikimate-phosphate synthase (epsps) gene and 258 bp fragment of Cry1Ab delta-endotoxin (cry1Ab) gene for GMO screening. The certified reference materials containing Roundup Ready soybean (RRS) and maize MON 810 were applied for the development and optimization of uniplex and multiplex PCR systems. Evaluation of amplification products by agarose gel electrophoresis using negative and positive controls confirmed high specificity and sensitivity at 0.1% GMO for both RRS and MON 810. The fourplex PCR was developed and optimized that allows simultaneous detection of three common transgenic elements, such as: CaMV 35S promoter, NOS terminator, epsps gene together with soybean-specific lectin gene. The triplex PCR developed enables simultaneous identification of transgenic elements, such as: 35S promoter and cry1Ab gene together with maize zein gene. The analysis of different processed foods demonstrated that multiplex PCR methods developed in this study are useful for accurate and fast screening of GM food products.
Environmental and Psychosocial Barriers to and Benefits of Cervical Cancer Screening in Kenya
Ragan, Kathleen; Lee Smith, Judith; Saraiya, Mona; Aketch, Millicent
2017-01-01
Abstract Background. Cervical cancer is the second most commonly diagnosed cancer in females and is a leading cause of cancer‐related mortality in Kenya; limited cervical cancer screening services may be a factor. Few studies have examined men's and women's perceptions on environmental and psychosocial barriers and benefits related to screening. Materials and Methods. In 2014, 60 women aged 25–49 years and 40 male partners participated in 10 focus groups (6 female and 4 male), in both rural and urban settings (Nairobi and Nyanza, Kenya), to explore perceptions about barriers to and benefits of cervical cancer screening. Focus groups were segmented by sex, language, geographic location, and screening status. Data were transcribed, translated into English, and analyzed by using qualitative software. Results. Participants identified screening as beneficial for initiating provider discussions about cancer but did not report it as a beneficial method for detecting precancers. Perceived screening barriers included access (transportation, cost), spousal approval, stigma, embarrassment during screening, concerns about speculum use causing infertility, fear of residual effects of test results, lack of knowledge, and religious or cultural beliefs. All participants reported concerns with having a male doctor perform screening tests; however, men uniquely reported the young age of a doctor as a barrier. Conclusion. Identifying perceived barriers and benefits among people in low‐ and middle‐income countries is important to successfully implementing emerging screening programs. The novel findings on barriers and benefits from this study can inform the development of targeted community outreach activities, communication strategies, and educational messages for patients, families, and providers. Implications for Practice. This article provides important information for stakeholders in clinical practice and research when assessing knowledge, beliefs, and acceptability of cervical cancer screening and treatment services in low‐ and middle‐resourced countries. Formative research findings provide information that could be used in the development of health interventions, community education messages, and materials. Additionally, this study illuminates the importance of understanding psychosocial barriers and facilitators to cervical cancer screening, community education, and reduction of stigma as important methods of improving prevention programs and increasing rates of screening among women. PMID:28167567
Huber, Ingrid; Block, Annette; Sebah, Daniela; Debode, Frédéric; Morisset, Dany; Grohmann, Lutz; Berben, Gilbert; Stebih, Dejan; Milavec, Mojca; Zel, Jana; Busch, Ulrich
2013-10-30
Worldwide, qualitative methods based on PCR are most commonly used as screening tools for genetically modified material in food and feed. However, the increasing number and diversity of genetically modified organisms (GMO) require effective methods for simultaneously detecting several genetic elements marking the presence of transgenic events. Herein we describe the development and validation of a pentaplex, as well as complementary triplex and duplex real-time PCR assays, for the detection of the most common screening elements found in commercialized GMOs: P-35S, T-nos, ctp2-cp4-epsps, bar, and pat. The use of these screening assays allows the coverage of many GMO events globally approved for commercialization. Each multiplex real-time PCR assay shows high specificity and sensitivity with an absolute limit of detection below 20 copies for the targeted sequences. We demonstrate by intra- and interlaboratory tests that the assays are robust as well as cost- and time-effective for GMO screening if applied in routine GMO analysis.
Vawda, Naseema B. M.; Milburn, Norweeta G.; Steyn, Renier; Zhang, Muyu
2016-01-01
Objective Adolescent suicidal behaviour is a public health concern in South Africa. The purpose of this manuscript is to report on the development of a screening tool for teachers to identify South African students who are most at risk for suicidal behaviour. This need is addressed within the context of the limited number of mental health professionals available to provide screening and care services in South Africa. Method Grade 8 students participated by completing sociodemographic questionnaires and self-report psychometric instruments. A screening tool for suicidal behaviour was developed using a four phase approach. Results Twelve factors for high risk suicidal behaviour were identified and included in the screening tool. While further research is needed to validate the screening tool, the findings provide a useful preliminary starting point for teachers to refer students at high risk for suicidal behaviour to mental health services for treatment. Conclusion This screening tool is based on factors that were identified as being associated with suicidal behaviour from local research on South African adolescents. The tool contributes to research on adolescent mental health, particularly suicidal behaviour, in developing low and middle income countries like South Africa, with the aim of creating African prevention and intervention programmes. PMID:28459269
Xu, Xiaoma; van de Craats, Anick M; de Bruyn, Peter C A M
2004-11-01
A highly sensitive screening method based on high performance liquid chromatography atmospheric pressure ionization mass spectrometry (HPLC-API-MS) has been developed for the analysis of 21 nitroaromatic, nitramine and nitrate ester explosives, which include the explosives most commonly encountered in forensic science. Two atmospheric pressure ionization (API) methods, atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI), and various experimental conditions have been applied to allow for the detection of all 21 explosive compounds. The limit of detection (LOD) in the full-scan mode has been found to be 0.012-1.2 ng on column for the screening of most explosives investigated. For nitrobenzene, an LOD of 10 ng was found with the APCI method in the negative mode. Although the detection of nitrobenzene, 2-, 3-, and 4-nitrotoluene is hindered by the difficult ionization of these compounds, we have found that by forming an adduct with glycine, LOD values in the range of 3-16 ng on column can be achieved. Compared with previous screening methods with thermospray ionization, the API method has distinct advantages, including simplicity and stability of the method applied, an extended screening range and a low detection limit for the explosives studied.
QSPR studies on the photoinduced-fluorescence behaviour of pharmaceuticals and pesticides.
López-Malo, D; Bueso-Bordils, J I; Duart, M J; Alemán-López, P A; Martín-Algarra, R V; Antón-Fos, G M; Lahuerta-Zamora, L; Martínez-Calatayud, J
2017-07-01
Fluorimetric analysis is still a growing line of research in the determination of a wide range of organic compounds, including pharmaceuticals and pesticides, which makes necessary the development of new strategies aimed at improving the performance of fluorescence determinations as well as the sensitivity and, especially, the selectivity of the newly developed analytical methods. In this paper are presented applications of a useful and growing tool suitable for fostering and improving research in the analytical field. Experimental screening, molecular connectivity and discriminant analysis are applied to organic compounds to predict their fluorescent behaviour after their photodegradation by UV irradiation in a continuous flow manifold (multicommutation flow assembly). The screening was based on online fluorimetric measurement and comprised pre-selected compounds with different molecular structures (pharmaceuticals and some pesticides with known 'native' fluorescent behaviour) to study their changes in fluorescent behaviour after UV irradiation. Theoretical predictions agree with the results from the experimental screening and could be used to develop selective analytical methods, as well as helping to reduce the need for expensive, time-consuming and trial-and-error screening procedures.
Schiebel, Johannes; Radeva, Nedyalka; Köster, Helene; Metz, Alexander; Krotzky, Timo; Kuhnert, Maren; Diederich, Wibke E; Heine, Andreas; Neumann, Lars; Atmanene, Cedric; Roecklin, Dominique; Vivat-Hannah, Valérie; Renaud, Jean-Paul; Meinecke, Robert; Schlinck, Nina; Sitte, Astrid; Popp, Franziska; Zeeb, Markus; Klebe, Gerhard
2015-09-01
Fragment-based lead discovery is gaining momentum in drug development. Typically, a hierarchical cascade of several screening techniques is consulted to identify fragment hits which are then analyzed by crystallography. Because crystal structures with bound fragments are essential for the subsequent hit-to-lead-to-drug optimization, the screening process should distinguish reliably between binders and non-binders. We therefore investigated whether different screening methods would reveal similar collections of putative binders. First we used a biochemical assay to identify fragments that bind to endothiapepsin, a surrogate for disease-relevant aspartic proteases. In a comprehensive screening approach, we then evaluated our 361-entry library by using a reporter-displacement assay, saturation-transfer difference NMR, native mass spectrometry, thermophoresis, and a thermal shift assay. While the combined results of these screening methods retrieve 10 of the 11 crystal structures originally predicted by the biochemical assay, the mutual overlap of individual hit lists is surprisingly low, highlighting that each technique operates on different biophysical principles and conditions. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
IspE Inhibitors Identified by a Combination of In Silico and In Vitro High-Throughput Screening
Tidten-Luksch, Naomi; Grimaldi, Raffaella; Torrie, Leah S.; Frearson, Julie A.; Hunter, William N.; Brenk, Ruth
2012-01-01
CDP-ME kinase (IspE) contributes to the non-mevalonate or deoxy-xylulose phosphate (DOXP) pathway for isoprenoid precursor biosynthesis found in many species of bacteria and apicomplexan parasites. IspE has been shown to be essential by genetic methods and since it is absent from humans it constitutes a promising target for antimicrobial drug development. Using in silico screening directed against the substrate binding site and in vitro high-throughput screening directed against both, the substrate and co-factor binding sites, non-substrate-like IspE inhibitors have been discovered and structure-activity relationships were derived. The best inhibitors in each series have high ligand efficiencies and favourable physico-chemical properties rendering them promising starting points for drug discovery. Putative binding modes of the ligands were suggested which are consistent with established structure-activity relationships. The applied screening methods were complementary in discovering hit compounds, and a comparison of both approaches highlights their strengths and weaknesses. It is noteworthy that compounds identified by virtual screening methods provided the controls for the biochemical screens. PMID:22563402
Jin, Yu; Xiao, Yuan-sheng; Zhang, Fei-fang; Xue, Xing-ya; Xu, Qing; Liang, Xin-miao
2008-02-13
The traditional Chinese medicine (TCM) is a complex system, which always consists of numerous compounds with significant difference in the content and physical and chemical properties. In this paper, a screening method based on target molecular weights was developed to characterize the flavonoid glycosides in the flower of Carthamus tinctorius L. The screening tables of aglycone and glycan were designed, respectively, in order to select and combine freely. The multiple reaction monitoring (MRM) scan mode with higher sensitivity and selectivity was adopted in the screening, which benefit the characterization for the minor components. Seventy-seven flavonoid glycosides were screened out finally, and their structures were characterized by tandem mass spectrometric method in both positive and negative ion modes. The glycosylation mode, aglycone, sequence and/or the interglycosidic linkages of the glycan portion and glycosylation position were elucidated by the fragmentation rule in the MS. Numerous compounds screened out with this method showed the structure variety in secondary plant metabolites, and the purposeful screening systemically and subsequent structure characterization offered more information about the chemical constitutions of TCM.
Developments in Screening Tests and Strategies for Colorectal Cancer
Sovich, Justin L.; Sartor, Zachary
2015-01-01
Background. Worldwide, colorectal cancer (CRC) is the third most common cancer in men and second most common in women. It is the fourth most common cause of cancer mortality. In the United States, CRC is the third most common cause of cancer and second most common cause of cancer mortality. Incidence and mortality rates have steadily fallen, primarily due to widespread screening. Methods. We conducted keyword searches on PubMed in four categories of CRC screening: stool, endoscopic, radiologic, and serum, as well as news searches in Medscape and Google News. Results. Colonoscopy is the gold standard for CRC screening and the most common method in the United States. Technological improvements continue to be made, including the promising “third-eye retroscope.” Fecal occult blood remains widely used, particularly outside the United States. The first at-home screen, a fecal DNA screen, has also recently been approved. Radiological methods are effective but seldom used due to cost and other factors. Serum tests are largely experimental, although at least one is moving closer to market. Conclusions. Colonoscopy is likely to remain the most popular screening modality for the immediate future, although its shortcomings will continue to spur innovation in a variety of modalities. PMID:26504799
Hagar, Yolanda C; Harvey, Danielle J; Beckett, Laurel A
2016-08-30
We develop a multivariate cure survival model to estimate lifetime patterns of colorectal cancer screening. Screening data cover long periods of time, with sparse observations for each person. Some events may occur before the study begins or after the study ends, so the data are both left-censored and right-censored, and some individuals are never screened (the 'cured' population). We propose a multivariate parametric cure model that can be used with left-censored and right-censored data. Our model allows for the estimation of the time to screening as well as the average number of times individuals will be screened. We calculate likelihood functions based on the observations for each subject using a distribution that accounts for within-subject correlation and estimate parameters using Markov chain Monte Carlo methods. We apply our methods to the estimation of lifetime colorectal cancer screening behavior in the SEER-Medicare data set. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
Fujihara, Hidehiko; Hino, Mika; Takashita, Hideharu; Kajiwara, Yasuhiro; Okamoto, Keiko; Furukawa, Kensuke
2014-01-01
We developed an efficient screening method for Saccharomyces cerevisiae strains from environmental isolates. MultiPlex PCR was performed targeting four brewing S. cerevisiae genes (SSU1, AWA1, BIO6, and FLO1). At least three genes among the four were amplified from all S. cerevisiae strains. The use of this method allowed us to successfully obtain S. cerevisiae strains.
Gourgari, Evgenia; Spanakis, Elias; Dobs, Adrian Sandra
2016-01-01
Polycystic ovary syndrome (PCOS) is a syndrome associated with insulin resistance (IR), obesity, infertility, and increased cardiometabolic risk. This is a descriptive review of several mechanisms that can explain the IR among women with PCOS, other risk factors for the development of diabetes, and the screening methods used for the detection of glucose intolerance in women with PCOS. Few mechanisms can explain IR in women with PCOS such as obesity, insulin receptor signaling defects, and inhibition of insulin-mediated glucose uptake in adipocytes. Women with PCOS have additional risk factors for the development of glucose intolerance such as family history of diabetes, use of oral contraceptives, anovulation, and age. The Androgen Society in 2007 and the Endocrine Society in 2013 recommended using oral glucose tolerance test as a screening tool for abnormal glucose tolerance in all women with PCOS. The approach to detection of glucose intolerance among women with PCOS varies among health care providers. Large prospective studies are still needed for the development of guidelines with strong evidence. When assessing risk of future diabetes in women with PCOS, it is important to take into account the method used for screening as well as other risk factors that these women might have. PMID:27570464
Gourgari, Evgenia; Spanakis, Elias; Dobs, Adrian Sandra
2016-01-01
Polycystic ovary syndrome (PCOS) is a syndrome associated with insulin resistance (IR), obesity, infertility, and increased cardiometabolic risk. This is a descriptive review of several mechanisms that can explain the IR among women with PCOS, other risk factors for the development of diabetes, and the screening methods used for the detection of glucose intolerance in women with PCOS. Few mechanisms can explain IR in women with PCOS such as obesity, insulin receptor signaling defects, and inhibition of insulin-mediated glucose uptake in adipocytes. Women with PCOS have additional risk factors for the development of glucose intolerance such as family history of diabetes, use of oral contraceptives, anovulation, and age. The Androgen Society in 2007 and the Endocrine Society in 2013 recommended using oral glucose tolerance test as a screening tool for abnormal glucose tolerance in all women with PCOS. The approach to detection of glucose intolerance among women with PCOS varies among health care providers. Large prospective studies are still needed for the development of guidelines with strong evidence. When assessing risk of future diabetes in women with PCOS, it is important to take into account the method used for screening as well as other risk factors that these women might have.
2012-01-01
Background Economic evaluation of newborn screening poses specific methodological challenges. Amongst others, these challenges refer to the use of quality adjusted life years (QALYs) in newborns, and which costs and outcomes need to be considered in a full evaluation of newborn screening programmes. Because of the increasing scale and scope of such programmes, a better understanding of the methods of high-quality economic evaluations may be crucial for both producers/authors and consumers/reviewers of newborn screening-related economic evaluations. The aim of this study was therefore to develop specific guidelines designed to assess and improve the methodological quality of economic evaluations in newborn screening. Methods To develop the guidelines, existing guidelines for assessing the quality of economic evaluations were identified through a literature search, and were reviewed and consolidated using a deductive iterative approach. In a subsequent test phase, these guidelines were applied to various economic evaluations which acted as case studies. Results The guidelines for assessing and improving the methodological quality of economic evaluations in newborn screening are organized into 11 categories: “bibliographic details”, “study question and design”, “modelling”, “health outcomes”, “costs”, “discounting”, “presentation of results”, “sensitivity analyses”, “discussion”, “conclusions”, and “commentary”. Conclusions The application of the guidelines highlights important issues regarding newborn screening-related economic evaluations, and underscores the need for such issues to be afforded greater consideration in future economic evaluations. The variety in methodological quality detected by this study reveals the need for specific guidelines on the appropriate methods for conducting sound economic evaluations in newborn screening. PMID:22947299
NASA Astrophysics Data System (ADS)
Schierz, Amanda C.; King, Ross D.
Compounds in drug screening-libraries should resemble pharmaceuticals. To operationally test this, we analysed the compounds in terms of known drug-like filters and developed a novel machine learning method to discriminate approved pharmaceuticals from “drug-like” compounds. This method uses both structural features and molecular properties for discrimination. The method has an estimated accuracy of 91% in discriminating between the Maybridge HitFinder library and approved pharmaceuticals, and 99% between the NATDiverse collection (from Analyticon Discovery) and approved pharmaceuticals. These results show that Lipinski’s Rule of 5 for oral absorption is not sufficient to describe “drug-likeness” and be the main basis of screening-library design.
Optical characterization of display screens by speckle patterns
NASA Astrophysics Data System (ADS)
Pozo, Antonio M.; Castro, José J.; Rubiño, Manuel
2013-10-01
In recent years, flat-panel display (FPD) technology has undergone great development, and now FPDs appear in many devices. A significant element in FPD manufacturing is the display front surface. Manufacturers sell FPDs with different types of front surfaces, which can be matte (also called anti-glare) or glossy screens. Users who prefer glossy screens consider these displays to show more vivid colors compared with matte-screen displays. However, on the glossy screens, external light sources may cause unpleasant reflections that can be reduced by a matte treatment in the front surface. In this work, we present a method to characterize FPD screens using laser-speckle patterns. We characterize three FPDs: a Samsung XL2370 LCD monitor of 23 in. with matte screen, a Toshiba Satellite A100 LCD laptop of 15.4 in. with glossy screen, and a Grammata Papyre 6.1 electronic book reader of 6 in. with ePaper screen (E-ink technology). The results show great differences in speckle-contrast values for the three screens characterized and, therefore, this work shows the feasibility of this method for characterizing and comparing FPDs that have different types of front surfaces.
Introducing Bayesian thinking to high-throughput screening for false-negative rate estimation.
Wei, Xin; Gao, Lin; Zhang, Xiaolei; Qian, Hong; Rowan, Karen; Mark, David; Peng, Zhengwei; Huang, Kuo-Sen
2013-10-01
High-throughput screening (HTS) has been widely used to identify active compounds (hits) that bind to biological targets. Because of cost concerns, the comprehensive screening of millions of compounds is typically conducted without replication. Real hits that fail to exhibit measurable activity in the primary screen due to random experimental errors will be lost as false-negatives. Conceivably, the projected false-negative rate is a parameter that reflects screening quality. Furthermore, it can be used to guide the selection of optimal numbers of compounds for hit confirmation. Therefore, a method that predicts false-negative rates from the primary screening data is extremely valuable. In this article, we describe the implementation of a pilot screen on a representative fraction (1%) of the screening library in order to obtain information about assay variability as well as a preliminary hit activity distribution profile. Using this training data set, we then developed an algorithm based on Bayesian logic and Monte Carlo simulation to estimate the number of true active compounds and potential missed hits from the full library screen. We have applied this strategy to five screening projects. The results demonstrate that this method produces useful predictions on the numbers of false negatives.
Purves, Randy W; Khazaei, Hamid; Vandenberg, Albert
2018-08-01
Although faba bean provides environmental and health benefits, vicine and convicine (v-c) limit its use as a source of vegetable protein. Crop improvement efforts to minimize v-c concentration require low-cost, rapid screening methods to distinguish between high and low v-c genotypes to accelerate development of new cultivars and to detect out-crossing events. To assist crop breeders, we developed a unique and rapid screening method that uses a 60 s instrumental analysis step to accurately distinguish between high and low v-c genotypes. The method involves flow injection analysis (FIA) coupled with tandem mass spectrometry (i.e., selective reaction monitoring, SRM). Using seeds with known v-c levels as calibrants, measured v-c levels were comparable with liquid chromatography (LC)-SRM results and the method was used to screen 370 faba bean genotypes. Widespread use of FIA-SRM will accelerate breeding of low v-c faba bean, thereby alleviating concerns about anti-nutritional effects of v-c in this crop. Copyright © 2018 Elsevier Ltd. All rights reserved.
Using pathway modules as targets for assay development in xenobiotic screening
Toxicology and pharmaceutical research is increasingly making use of high throughout-screening (HTS) methods to assess the effects of chemicals on molecular pathways, cells and tissues. Whole-genome microarray analysis provides broad information on the response of biological syst...
How to select the correct education strategy: when not to go online.
Klingbeil, Carol G; Johnson, Norah L; Totka, Joan P; Doyle, Lynn
2009-01-01
Screening for intimate partner violence is an important injury prevention strategy. Nurses who develop staff education, to promote screening, need to select a method that is sensitive to learners. Online learning, although convenient, is not well suited to sensitive topics such as screening for intimate partner violence. The purpose of this article is to describe a curriculum for intimate partner violence screening based on self-efficacy theory, which includes a hospital-produced video, a role play, and a discussion.
Estimating Development Cost of an Interactive Website Based Cancer Screening Promotion Program
Lairson, David R.; Chung, Tong Han; Smith, Lisa G.; Springston, Jeffrey K.; Champion, Victoria L.
2015-01-01
Objectives The aim of this study was to estimate the initial development costs for an innovative talk show format tailored intervention delivered via the interactive web, for increasing cancer screening in women 50 to 75 who were non-adherent to screening guidelines for colorectal cancer and/or breast cancer. Methods The cost of the intervention development was estimated from a societal perspective. Micro costing methods plus vendor contract costs were used to estimate cost. Staff logs were used to track personnel time. Non-personnel costs include all additional resources used to produce the intervention. Results Development cost of the interactive web based intervention was $.39 million, of which 77% was direct cost. About 98% of the cost was incurred in personnel time cost, contract cost and overhead cost. Conclusions The new web-based disease prevention medium required substantial investment in health promotion and media specialist time. The development cost was primarily driven by the high level of human capital required. The cost of intervention development is important information for assessing and planning future public and private investments in web-based health promotion interventions. PMID:25749548
Design of a projection display screen with vanishing color shift for rear-projection HDTV
NASA Astrophysics Data System (ADS)
Liu, Xiu; Zhu, Jin-lin
1996-09-01
Using bi-convex cylinder lens with matrix structure, the transmissive projection display screen with high contrast and wider viewing angle has been widely used in large rear projection TV and video projectors, it obtained a inhere color shift and puzzled the designer of display screen for RGB projection tube in-line adjustment. Based on the method of light beam racing, the general software of designing projection display screen has been developed and the computer model of vanishing color shift for rear projection HDTV has bee completed. This paper discussed the practical designing method to vanish the defect of color shift and mentioned the relations between the primary optical parameters of display screen and relative geometry sizes of lens' surface. The distributions of optical gain to viewing angle and the influences on engineering design are briefly analyzed.
Montes, Alejandro; Pazos, Gustavo
2016-02-01
Identifying children at risk of failing the National Developmental Screening Test by combining prevalences of children suspected of having inapparent developmental disorders (IDDs) and associated risk factors (RFs) would allow to save resources. 1. To estimate the prevalence of children suspected of having IDDs. 2. To identify associated RFs. 3. To assess three methods developed based on observed RFs and propose a pre-screening procedure. The National Developmental Screening Test was administered to 60 randomly selected children aged between 2 and 4 years old from a socioeconomically disadvantaged area from Puerto Madryn. Twenty-four biological and socioenvironmental outcome measures were assessed in order to identify potential RFs using bivariate and multivariate analyses. The likelihood of failing the screening test was estimated as follows: 1. a multivariate logistic regression model was developed; 2. a relationship was established between the number of RFs present in each child and the percentage of children who failed the test; 3. these two methods were combined. The prevalence of children suspected of having IDDs was 55.0% (95% confidence interval: 42.4%-67.6%). Six RFs were initially identified using the bivariate approach. Three of them (maternal education, number of health checkups and Z scores for height-for-age, and maternal age) were included in the logistic regression model, which has a greater explanatory power. The third method included in the assessment showed greater sensitivity and specificity (85% and 79%, respectively). The estimated prevalence of children suspected of having IDDs was four times higher than the national standards. Seven RFs were identified. Combining the analysis of risk factor accumulation and a multivariate model provides a firm basis for developing a sensitive, specific and practical pre-screening procedure for socioeconomically disadvantaged areas. Sociedad Argentina de Pediatría.
Development of a screening tool to predict malnutrition among children under two years old in Zambia
Hasegawa, Junko; Ito, Yoichi M; Yamauchi, Taro
2017-01-01
ABSTRACT Background: Maternal and child undernutrition is an important issue, particularly in low- and middle-income countries. Children at high risk of malnutrition should be prioritized to receive necessary interventions to minimize such risk. Several risk factors have been proposed; however, until now, there has been no appropriate evaluation method to identify these children. In sub-Saharan Africa, children commonly receive regular check-ups from community health workers. A simple and easy nutrition assessment method is therefore needed for use by semi-professional health workers. Objectives: The aim of this study was to develop and test a practical screening tool for community use in predicting growth stunting in children under two years in rural Zambia. Methods: Field research was conducted from July to August 2014 in Southern Province, Zambia. Two hundred and sixty-four mother-child pairs participated in the study. Anthropometric measurements were performed on all children and mothers, and all mothers were interviewed. Risk factors for the screening test were estimated by using least absolute shrinkage and selection operator analysis. After re-evaluating all participants using the new screening tool, a receiver operating characteristic curve was drawn to set the cut-off value. Sensitivity and specificity were also calculated. Results: The screening tool included age, weight-for-age Z-score status, birth weight, feeding status, history of sibling death, multiple birth, and maternal education level. The total score ranged from 0 to 22, and the cut-off value was eight. Sensitivity and specificity were 0.963 and 0.697 respectively. Conclusions: A screening tool was developed to predict children at high risk of malnutrition living in Zambia. Further longitudinal studies are needed to confirm the test’s validity in detecting future stunting and to investigate the effectiveness of malnutrition treatment. PMID:28730929
Tian, Yuzhen; Guo, Jin; Wang, Rui; Wang, Tingfeng
2011-09-12
In order to research the statistical properties of Gaussian beam propagation through an arbitrary thickness random phase screen for adaptive optics and laser communication application in the laboratory, we establish mathematic models of statistical quantities, which are based on the Rytov method and the thin phase screen model, involved in the propagation process. And the analytic results are developed for an arbitrary thickness phase screen based on the Kolmogorov power spectrum. The comparison between the arbitrary thickness phase screen and the thin phase screen shows that it is more suitable for our results to describe the generalized case, especially the scintillation index.
How to improve colon cancer screening rates
Alberti, Luiz Ronaldo; Garcia, Diego Paim Carvalho; Coelho, Debora Lucciola; De Lima, David Correa Alves; Petroianu, Andy
2015-01-01
Colorectal carcinoma is a common cause of death throughout the world and may be prevented by routine control, which can detect precancerous neoplasms and early cancers before they undergo malignant transformation or metastasis. Three strategies may improve colon cancer screening rates: convince the population about the importance of undergoing a screening test; achieve higher efficacy in standard screening tests and make them more available to the community and develop new more sensitive and efficacious screening methods and make them available as routine tests. In this light, the present study seeks to review these three means through which to increase colon cancer screening rates. PMID:26688708
Optical characterization of display screens by speckle-contrast measurements
NASA Astrophysics Data System (ADS)
Pozo, Antonio M.; Castro, José J.; Rubiño, Manuel
2012-10-01
In recent years, the flat-panel display (FPD) technology has undergone great development. Currently, FPDs are present in many devices. A significant element in FPD manufacturing is the display front surface. Manufacturers sell FPDs with different types of front surface which can be matte (also called anti-glare) or glossy screens. Users who prefer glossy screens consider images shown in these types of displays to have more vivid colours compared with matte-screen displays. However, external light sources may cause unpleasant reflections on the glossy screens. These reflections can be reduced by a matte treatment in the front surface of FPDs. In this work, we present a method to characterize the front surface of FPDs using laser speckle patterns. We characterized three FPDs: a Samsung XL2370 LCD monitor of 23" with matte screen, a Toshiba Satellite A100 laptop of 15.4" with glossy screen, and a Papyre electronic book reader. The results show great differences in speckle contrast values for the three screens characterized and, therefore, this work shows the feasibility of this method for characterizing and comparing FPDs which have different types of front surfaces.
Building a virtual ligand screening pipeline using free software: a survey.
Glaab, Enrico
2016-03-01
Virtual screening, the search for bioactive compounds via computational methods, provides a wide range of opportunities to speed up drug development and reduce the associated risks and costs. While virtual screening is already a standard practice in pharmaceutical companies, its applications in preclinical academic research still remain under-exploited, in spite of an increasing availability of dedicated free databases and software tools. In this survey, an overview of recent developments in this field is presented, focusing on free software and data repositories for screening as alternatives to their commercial counterparts, and outlining how available resources can be interlinked into a comprehensive virtual screening pipeline using typical academic computing facilities. Finally, to facilitate the set-up of corresponding pipelines, a downloadable software system is provided, using platform virtualization to integrate pre-installed screening tools and scripts for reproducible application across different operating systems. © The Author 2015. Published by Oxford University Press.
Building a virtual ligand screening pipeline using free software: a survey
2016-01-01
Virtual screening, the search for bioactive compounds via computational methods, provides a wide range of opportunities to speed up drug development and reduce the associated risks and costs. While virtual screening is already a standard practice in pharmaceutical companies, its applications in preclinical academic research still remain under-exploited, in spite of an increasing availability of dedicated free databases and software tools. In this survey, an overview of recent developments in this field is presented, focusing on free software and data repositories for screening as alternatives to their commercial counterparts, and outlining how available resources can be interlinked into a comprehensive virtual screening pipeline using typical academic computing facilities. Finally, to facilitate the set-up of corresponding pipelines, a downloadable software system is provided, using platform virtualization to integrate pre-installed screening tools and scripts for reproducible application across different operating systems. PMID:26094053
Jia, Yao; Li, Shuang; Yang, Ru; Zhou, Hang; Xiang, Qunying; Hu, Ting; Zhang, Qinghua; Chen, Zhilan; Ma, Ding; Feng, Ling
2013-01-01
Cervical cancer screening is an effective method for reducing the incidence and mortality of cervical cancer, but the screening attendance rate in developing countries is far from satisfactory, especially in rural areas. Wufeng is a region of high cervical cancer incidence in China. This study aimed to investigate the issues that concern cervical cancer and screening and the factors that affect women's willingness to undergo cervical cancer screening in the Wufeng area. A cross-sectional survey of women was conducted to determine their knowledge about cervical cancer and screening, demographic characteristics and the barriers to screening. Women who were willing to undergo screenings had higher knowledge levels. "Anxious feeling once the disease was diagnosed" (47.6%), "No symptoms/discomfort" (34.1%) and "Do not know the benefits of cervical cancer screening" (13.4%) were the top three reasons for refusing cervical cancer screening. Women who were younger than 45 years old or who had lower incomes, positive family histories of cancer, secondary or higher levels of education, higher levels of knowledge and fewer barriers to screening were more willing to participate in cervical cancer screenings than women without these characteristics. Efforts are needed to increase women's knowledge about cervical cancer, especially the screening methods, and to improve their perceptions of the screening process for early detection to reduce cervical cancer incidence and mortality rates.
NASA Technical Reports Server (NTRS)
Klockhoff, I.
1977-01-01
An automatic, computerized method was developed to classify results from a screening of employees exposed to noise, resulting in a fast and effective method of identifying and taking measures against auditory trauma. This technique also satisfies the urgent need for quick discovery of cases which deserve compensation in accordance with the Law on Industrial Accident Insurance. Unfortunately, use of this method increases the burden on the already overloaded investigatory resources of the auditory health care system.
Development of an ELA-DRA gene typing method based on pyrosequencing technology.
Díaz, S; Echeverría, M G; It, V; Posik, D M; Rogberg-Muñoz, A; Pena, N L; Peral-García, P; Vega-Pla, J L; Giovambattista, G
2008-11-01
The polymorphism of equine lymphocyte antigen (ELA) class II DRA gene had been detected by polymerase chain reaction-single-strand conformational polymorphism (PCR-SSCP) and reference strand-mediated conformation analysis. These methodologies allowed to identify 11 ELA-DRA exon 2 sequences, three of which are widely distributed among domestic horse breeds. Herein, we describe the development of a pyrosequencing-based method applicable to ELA-DRA typing, by screening samples from eight different horse breeds previously typed by PCR-SSCP. This sequence-based method would be useful in high-throughput genotyping of major histocompatibility complex genes in horses and other animal species, making this system interesting as a rapid screening method for animal genotyping of immune-related genes.
Liu, Min; Zhang, Chunsun; Liu, Feifei
2015-09-03
In this work, we first introduce the fabrication of microfluidic cloth-based analytical devices (μCADs) using a wax screen-printing approach that is suitable for simple, inexpensive, rapid, low-energy-consumption and high-throughput preparation of cloth-based analytical devices. We have carried out a detailed study on the wax screen-printing of μCADs and have obtained some interesting results. Firstly, an analytical model is established for the spreading of molten wax in cloth. Secondly, a new wax screen-printing process has been proposed for fabricating μCADs, where the melting of wax into the cloth is much faster (∼5 s) and the heating temperature is much lower (75 °C). Thirdly, the experimental results show that the patterning effects of the proposed wax screen-printing method depend to a certain extent on types of screens, wax melting temperatures and melting time. Under optimized conditions, the minimum printing width of hydrophobic wax barrier and hydrophilic channel is 100 μm and 1.9 mm, respectively. Importantly, the developed analytical model is also well validated by these experiments. Fourthly, the μCADs fabricated by the presented wax screen-printing method are used to perform a proof-of-concept assay of glucose or protein in artificial urine with rapid high-throughput detection taking place on a 48-chamber cloth-based device and being performed by a visual readout. Overall, the developed cloth-based wax screen-printing and arrayed μCADs should provide a new research direction in the development of advanced sensor arrays for detection of a series of analytes relevant to many diverse applications. Copyright © 2015 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Satoh, Hitoshi; Niki, Noboru; Eguchi, Kenji; Ohmatsu, Hironobu; Kakinuma, Ryutaru; Moriyama, Noriyuki
2009-02-01
Mass screening based on multi-helical CT images requires a considerable number of images to be read. It is this time-consuming step that makes the use of helical CT for mass screening impractical at present. Moreover, the doctor who diagnoses a medical image is insufficient in Japan. To overcome these problems, we have provided diagnostic assistance methods to medical screening specialists by developing a lung cancer screening algorithm that automatically detects suspected lung cancers in helical CT images, a coronary artery calcification screening algorithm that automatically detects suspected coronary artery calcification and a vertebra body analysis algorithm for quantitative evaluation of osteoporosis likelihood by using helical CT scanner for the lung cancer mass screening. The functions to observe suspicious shadow in detail are provided in computer-aided diagnosis workstation with these screening algorithms. We also have developed the telemedicine network by using Web medical image conference system with the security improvement of images transmission, Biometric fingerprint authentication system and Biometric face authentication system. Biometric face authentication used on site of telemedicine makes "Encryption of file" and "Success in login" effective. As a result, patients' private information is protected. We can share the screen of Web medical image conference system from two or more web conference terminals at the same time. An opinion can be exchanged mutually by using a camera and a microphone that are connected with workstation. Based on these diagnostic assistance methods, we have developed a new computer-aided workstation and a new telemedicine network that can display suspected lesions three-dimensionally in a short time. The results of this study indicate that our radiological information system without film by using computer-aided diagnosis workstation and our telemedicine network system can increase diagnostic speed, diagnostic accuracy and security improvement of medical information.
Urine Multi-drug Screening with GC-MS or LC-MS-MS Using SALLE-hybrid PPT/SPE.
Lee, Junhui; Park, Jiwon; Go, Ahra; Moon, Heesung; Kim, Sujin; Jung, Sohee; Jeong, Wonjoon; Chung, Heesun
2018-05-14
To intoxicated patients in the emergency room, toxicological analysis can be considerably helpful for identifying the involved toxicants. In order to develop a urine multi-drug screening (UmDS) method, gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS-MS) were used to determine targeted and unknown toxicants in urine. A GC-MS method in scan mode was validated for selectivity, limit of detection (LOD) and recovery. An LC-MS-MS multiple reaction monitoring (MRM) method was validated for lower LOD, recovery and matrix effect. The results of the screening analysis were compared with patient medical records to check the reliability of the screen. Urine samples collected from an emergency room were extracted through a combination of salting-out assisted liquid-liquid extraction (SALLE) and hybrid protein precipitation/solid phase extraction (hybrid PPT/SPE) plates and examined by GC-MS and LC-MS-MS. GC-MS analysis was performed as unknown drug screen and LC-MS-MS analysis was conducted as targeted drug screen. After analysis by GC-MS, a library search was conducted using an in-house library established with the automated mass spectral deconvolution and identification system (AMDISTM). LC-MS-MS used Cliquid®2.0 software for data processing and acquisition in MRM mode. An UmDS method by GC-MS and LC-MS-MS was developed by using a SALLE-hybrid PPT/SPE and in-house library. The results of UmDS by GC-MS and LC-MS-MS showed that toxicants could be identified from 185 emergency room patient samples containing unknown toxicants. Zolpidem, acetaminophen and citalopram were the most frequently encountered drugs in emergency room patients. The UmDS analysis developed in this study can be used effectively to detect toxic substances in a short time. Hence, it could be utilized in clinical and forensic toxicology practices.
Ankley, Gerald T.; Mihaich, Ellen; Stahl, Ralph G.; Tillitt, Donald E.; Colborn, Theo; McMaster, Suzzanne; Miller, Ron; Bantle, John; Campbell, Pamela; Denslow, Nancy; Dickerson, Richard L.; Folmar, Leroy C.; Fry, Michael; Giesy, John P.; Gray, L. Earl; Guiney, Patrick; Hutchinson, Thomas; Kennedy, Sean W.; Kramer, Vincent; LeBlanc, Gerald A.; Mayes, Monte; Nimrod, Alison; Patino, Reynaldo; Peterson, Richard; Purdy, Richard; Ringer, Robert; Thomas, Peter C.; Touart, Les; Van Der Kraak, Glen; Zacharewski, Tim
1998-01-01
The U.S. Congress has passed legislation requiring the U.S. Environmental Protection Agency (U.S. EPA) to develop, validate, and implement screening tests for identifying potential endocrine-disrupting chemicals within 3 years. To aid in the identification of methods suitable for this purpose, the U.S. EPA, the Chemical Manufacturers Association, and the World Wildlife Fund sponsored several workshops, including the present one, which dealt with wildlife species. This workshop was convened with 30 international scientists representing multiple disciplines in March 1997 in Kansas City, Missouri, USA. Participants at the meeting identified methods in terms of their ability to indicate (anti-) estrogenic/androgenic effects, particularly in the context of developmental and reproductive processes. Data derived from structure-activity relationship models and in vitro test systems, although useful in certain contexts, cannot at present replace in vivo tests as the sole basis for screening. A consensus was reached that existing mammalian test methods (e.g., with rats or mice) generally are suitable as screens for assessing potential (anti-) estrogenic/ androgenic effects in mammalian wildlife. However, due to factors such as among-class variation in receptor structure and endocrine function, it is uncertain if these mammalian assays would be of broad utility as screens for other classes of vertebrate wildlife. Existing full and partial life-cycle tests with some avian and fish species could successfully identify chemicals causing endocrine disruption; however, these long-term tests are not suitable for routine screening. However, a number of short-term tests with species from these two classes exist that could serve as effective screening tools for chemicals inducing (anti-) estrogenic/androgenic effects. Existing methods suitable for identifying chemicals with these mechanisms of action in reptiles and amphibians are limited, but in the future, tests with species from these classes may prove highly effective as screens. In the case of invertebrate species, too little is known at present about the biological role of estrogens and androgens in reproduction and development to recommend specific assays.
Ewing, Tom A; van Noord, Aster; Paul, Caroline E; van Berkel, Willem J H
2018-01-14
Vanillyl alcohol oxidase (VAO) and eugenol oxidase (EUGO) are flavin-dependent enzymes that catalyse the oxidation of para -substituted phenols. This makes them potentially interesting biocatalysts for the conversion of lignin-derived aromatic monomers to value-added compounds. To facilitate their biocatalytic exploitation, it is important to develop methods by which variants of the enzymes can be rapidly screened for increased activity towards substrates of interest. Here, we present the development of a screening assay for the substrate specificity of para -phenol oxidases based on the detection of hydrogen peroxide using the ferric-xylenol orange complex method. The assay was used to screen the activity of VAO and EUGO towards a set of twenty-four potential substrates. This led to the identification of 4-cyclopentylphenol as a new substrate of VAO and EUGO and 4-cyclohexylphenol as a new substrate of VAO. Screening of a small library of VAO and EUGO active-site variants for alterations in their substrate specificity led to the identification of a VAO variant (T457Q) with increased activity towards vanillyl alcohol (4-hydroxy-3-methoxybenzyl alcohol) and a EUGO variant (V436I) with increased activity towards chavicol (4-allylphenol) and 4-cyclopentylphenol. This assay provides a quick and efficient method to screen the substrate specificity of para -phenol oxidases, facilitating the enzyme engineering of known para- phenol oxidases and the evaluation of the substrate specificity of novel para -phenol oxidases.
Recent advances in quantitative high throughput and high content data analysis.
Moutsatsos, Ioannis K; Parker, Christian N
2016-01-01
High throughput screening has become a basic technique with which to explore biological systems. Advances in technology, including increased screening capacity, as well as methods that generate multiparametric readouts, are driving the need for improvements in the analysis of data sets derived from such screens. This article covers the recent advances in the analysis of high throughput screening data sets from arrayed samples, as well as the recent advances in the analysis of cell-by-cell data sets derived from image or flow cytometry application. Screening multiple genomic reagents targeting any given gene creates additional challenges and so methods that prioritize individual gene targets have been developed. The article reviews many of the open source data analysis methods that are now available and which are helping to define a consensus on the best practices to use when analyzing screening data. As data sets become larger, and more complex, the need for easily accessible data analysis tools will continue to grow. The presentation of such complex data sets, to facilitate quality control monitoring and interpretation of the results will require the development of novel visualizations. In addition, advanced statistical and machine learning algorithms that can help identify patterns, correlations and the best features in massive data sets will be required. The ease of use for these tools will be important, as they will need to be used iteratively by laboratory scientists to improve the outcomes of complex analyses.
Stolker, Alida A. M.; Peters, Ruud J. B.; Zuiderent, Richard; DiBussolo, Joseph M.
2010-01-01
There is an increasing interest in screening methods for quick and sensitive analysis of various classes of veterinary drugs with limited sample pre-treatment. Turbulent flow chromatography in combination with tandem mass spectrometry has been applied for the first time as an efficient screening method in routine analysis of milk samples. Eight veterinary drugs, belonging to seven different classes were selected for this study. After developing and optimising the method, parameters such as linearity, repeatability, matrix effects and carry-over were studied. The screening method was then tested in the routine analysis of 12 raw milk samples. Even without internal standards, the linearity of the method was found to be good in the concentration range of 50 to 500 µg/L. Regarding repeatability, RSDs below 12% were obtained for all analytes, with only a few exceptions. The limits of detection were between 0.1 and 5.2 µg/L, far below the maximum residue levels for milk set by the EU regulations. While matrix effects—ion suppression or enhancement—are obtained for all the analytes the method has proved to be useful for screening purposes because of its sensitivity, linearity and repeatability. Furthermore, when performing the routine analysis of the raw milk samples, no false positive or negative results were obtained. PMID:20379812
Feldman, Joshua; Davie, Sam; Kiran, Tara
2017-01-01
Our Family Health Team is located in Toronto, Canada and provides care to over 35 000 patients. Like many practices in Canada, we took an opportunistic approach to cervical, breast, and colorectal cancer screening. We wanted to shift to a proactive, population-based approach but were unable to systematically identify patients overdue for screening or calculate baseline screening rates. Our initiative had two goals: (1) to develop a method for systematically identifying patients eligible for screening and whether they were overdue and (2) to increase screening rates for cervical, breast, and colorectal cancer. Using external government data in combination with our practice's electronic medical record, we developed a process to identify patients eligible and overdue for cancer screening. After generating baseline data, we implemented an evidence-based, multifaceted intervention to improve cancer screening rates. We sent a personalized reminder letter to overdue patients, provided physicians with practice-level audit and feedback, and improved our electronic reminder function by updating charts with accurate data on the Fecal Occult Blood Test (FOBT). Following our initial intervention, we sought to maintain and further improve our screening rates by experimenting with alternative recall methods and collecting patient feedback. Screening rates significantly improved for all three cancers. Between March 2014 and December 2016, the cervical cancer screening rate increased from 60% to 71% (p<0.05), the breast cancer screening rate increased from 56% to 65% (p<0.05), and the overall colorectal screening rate increased from 59% to 70% (p<0.05). The increase in colorectal screening rates was largely due to an increase in FOBT screening from 18% to 25%, while colonoscopy screening remained relatively unchanged, shifting from 45% to 46%. We also found that patients living in low income neighbourhoods were less likely to be screened. Following our intervention, this equity gap narrowed modestly for breast and colorectal cancer but did not change for cervical cancer screening. Our future improvement efforts will be focused on reducing the gap in screening between patients living in low-income and high-income neighbourhoods while maintaining overall gains.
Rello, Luis; Aramendía, Maite; Belarra, Miguel A; Resano, Martín
2015-01-01
DBS have become a clinical specimen especially adequate for establishing home-based collection protocols. In this work, high-resolution continuum source graphite furnace atomic absorption spectrometry is evaluated for the direct monitoring of Pb in DBS, both as a quantitative tool and a screening method. The development of the screening model is based on the establishment of the unreliability region around the threshold limits, 100 or 50 μg l(-1). More than 500 samples were analyzed to validate the model. The screening method demonstrated high sensitivity (the rate of true positives detected was always higher than 95%), an excellent LOD (1 µg l(-1)) and high throughput (10 min per sample).
Flexible methods for segmentation evaluation: Results from CT-based luggage screening
Karimi, Seemeen; Jiang, Xiaoqian; Cosman, Pamela; Martz, Harry
2017-01-01
BACKGROUND Imaging systems used in aviation security include segmentation algorithms in an automatic threat recognition pipeline. The segmentation algorithms evolve in response to emerging threats and changing performance requirements. Analysis of segmentation algorithms’ behavior, including the nature of errors and feature recovery, facilitates their development. However, evaluation methods from the literature provide limited characterization of the segmentation algorithms. OBJECTIVE To develop segmentation evaluation methods that measure systematic errors such as oversegmentation and undersegmentation, outliers, and overall errors. The methods must measure feature recovery and allow us to prioritize segments. METHODS We developed two complementary evaluation methods using statistical techniques and information theory. We also created a semi-automatic method to define ground truth from 3D images. We applied our methods to evaluate five segmentation algorithms developed for CT luggage screening. We validated our methods with synthetic problems and an observer evaluation. RESULTS Both methods selected the same best segmentation algorithm. Human evaluation confirmed the findings. The measurement of systematic errors and prioritization helped in understanding the behavior of each segmentation algorithm. CONCLUSIONS Our evaluation methods allow us to measure and explain the accuracy of segmentation algorithms. PMID:24699346
Mohamed, S; Flint, S; Palmer, J; Fletcher, G C; Pitt, J I
2013-09-01
A simple and rapid screening method was developed for the detection of citrinin in fungal cultures using Coconut Cream Agar (CCA) described previously for detecting aflatoxin and ochratoxin A. Fifteen isolates of Penicillium citrinum were inoculated onto CCA and incubated at 25 and 30°C for 10 days. All isolates produced a distinct yellow green fluorescence on CCA when the reverse side of the agar plates were viewed under long wavelength UV light. Detection was optimal at 25°C after four to 5 days of incubation. Isolates positive by the CCA method also tested positive for citrinin production by the TLC agar plug method after growth on CCA, Czapek yeast extract agar and yeast extract sucrose agar. Control cultures were negative by both methods, indicating that the CCA Petri dish method was suitable for screening cultures for citrinin production. © 2013 The Society for Applied Microbiology.
Lai, Chang-Jiang-Sheng; Tan, Ting; Zeng, Su-Ling; Qi, Lian-Wen; Liu, Xin-Guang; Dong, Xin; Li, Ping; Liu, E-Hu
2015-05-10
The aim of this study was to develop a convenient method without pretreatments for nontarget discovery of interested compounds. The segment and exposure strategy, coupled with two mass spectrometer data acquisition methods was firstly proposed for screening the saponins in extract of Panax notoginseng (Sanqi) via high-performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry (HPLC-QTOF/MS). By gradually removing certain major or moderate interference compounds, the developed segment and exposure strategy could significantly improve the detection efficiency for trace compounds. Moreover, the newly developed five-point screening approach based on a modified mass defect filter strategy and the visual isotopic ion technique was verified to be efficient and reliable in picking out the interested precursor ions. In total, 234 ginsenosides including 67 potential new ones were characterized or tentatively identified from the extract of Sanqi. Particularly, some unusual compounds containing the branched glycosyl group or new substituted acyl groups were firstly reported. The proposed integrated strategy held a strong promise for analyses of the complex mixtures. Copyright © 2015 Elsevier B.V. All rights reserved.
Solliec, Morgan; Roy-Lachapelle, Audrey; Sauvé, Sébastien
2015-12-30
Swine manure can contain a wide range of veterinary antibiotics, which could enter the environment via manure spreading on agricultural fields. A suspect and non-target screening method was applied to swine manure samples to attempt to identify veterinary antibiotics and pharmaceutical compounds for a future targeted analysis method. A combination of suspect and non-target screening method was developed to identify various veterinary antibiotic families using liquid chromatography coupled with high-resolution mass spectrometry (LC/HRMS). The sample preparation was based on the physicochemical parameters of antibiotics for the wide scope extraction of polar compounds prior to LC/HRMS analysis. The amount of data produced was processed by applying restrictive thresholds and filters to significantly reduce the number of compounds found and eliminate matrix components. The suspect and non-target screening was applied on swine manure samples and revealed the presence of seven common veterinary antibiotics and some of their relative metabolites, including tetracyclines, β-lactams, sulfonamides and lincosamides. However, one steroid and one analgesic were also identified. The occurrence of the identified compounds was validated by comparing their retention times, isotopic abundance patterns and fragmentation patterns with certified standards. This identification method could be very useful as an initial step to screen for and identify emerging contaminants such as veterinary antibiotics and pharmaceuticals in environmental and biological matrices prior to quantification. Copyright © 2015 John Wiley & Sons, Ltd.
Lin, Pingtan; Zhao, Shulin; Lu, Xin; Ye, Fanggui; Wang, Hengshan
2013-08-01
A CE method based on a dual-enzyme co-immobilized capillary microreactor was developed for the simultaneous screening of multiple enzyme inhibitors. The capillary microreactor was prepared by co-immobilizing adenosine deaminase and xanthine oxidase on the inner wall at the inlet end of the separation capillary. The enzymes were first immobilized on gold nanoparticles, and the functionalized gold nanoparticles were then assembled on the inner wall at the inlet end of the separation capillary treated with polyethyleneimine. With the developed CE method, the substrates and products were baseline separated within 3 min. The activity of the immobilized enzyme can be directly detected by measuring the peak height of the products. A statistical parameter Z' factor was recommended for evaluation of the accuracy of a drug screening system. In the present study, it was calculated to be larger than 0.5, implying a good accuracy. Finally, screening a small compound library containing two known enzyme inhibitors and 20 natural extracts by the proposed method was demonstrated. The known inhibitors were identified, and some natural extracts were found to be positive for two-enzyme inhibition by the present method. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Screening DNA chip and event-specific multiplex PCR detection methods for biotech crops.
Lee, Seong-Hun
2014-11-01
There are about 80 biotech crop events that have been approved by safety assessment in Korea. They have been controlled by genetically modified organism (GMO) and living modified organism (LMO) labeling systems. The DNA-based detection method has been used as an efficient scientific management tool. Recently, the multiplex polymerase chain reaction (PCR) and DNA chip have been developed as simultaneous detection methods for several biotech crops' events. The event-specific multiplex PCR method was developed to detect five biotech maize events: MIR604, Event 3272, LY 038, MON 88017 and DAS-59122-7. The specificity was confirmed and the sensitivity was 0.5%. The screening DNA chip was developed from four endogenous genes of soybean, maize, cotton and canola respectively along with two regulatory elements and seven genes: P35S, tNOS, pat, bar, epsps1, epsps2, pmi, cry1Ac and cry3B. The specificity was confirmed and the sensitivity was 0.5% for four crops' 12 events: one soybean, six maize, three cotton and two canola events. The multiplex PCR and DNA chip can be available for screening, gene-specific and event-specific analysis of biotech crops as efficient detection methods by saving on workload and time. © 2014 Society of Chemical Industry. © 2014 Society of Chemical Industry.
ABSTRACT BODY: Thousands of chemicals lack adequate testing for adverse effects on nervous system development, stimulating research into alternative methods to screen chemicals for potential developmental neurotoxicity. Microelectrode arrays (MEA) collect action potential spiking...
Proposal of Screening Method of Sleep Disordered Breathing Using Fiber Grating Vision Sensor
NASA Astrophysics Data System (ADS)
Aoki, Hirooki; Nakamura, Hidetoshi; Nakajima, Masato
Every conventional respiration monitoring technique requires at least one sensor to be attached to the body of the subject during measurement, thereby imposing a sense of restraint that results in aversion against measurements that would last over consecutive days. To solve this problem, we developed a respiration monitoring system for sleepers, and it uses a fiber-grating vision sensor, which is a type of active image sensor to achieve non-contact respiration monitoring. In this paper, we verified the effectiveness of the system, and proposed screening method of the sleep disordered breathing. It was shown that our system could equivalently measure the respiration with thermistor and accelerograph. And, the respiratory condition of sleepers can be grasped by our screening method in one look, and it seems to be useful for the support of the screening of sleep disordered breathing.
Methods have been developed for screening and assessing the level of volatile, semi-volatile and non-volatile organic pollutants in human blood. The specific methodology is developed for measuring the presence of "native" compounds rather than their metabolites. Spe...
Large-scale virtual screening on public cloud resources with Apache Spark.
Capuccini, Marco; Ahmed, Laeeq; Schaal, Wesley; Laure, Erwin; Spjuth, Ola
2017-01-01
Structure-based virtual screening is an in-silico method to screen a target receptor against a virtual molecular library. Applying docking-based screening to large molecular libraries can be computationally expensive, however it constitutes a trivially parallelizable task. Most of the available parallel implementations are based on message passing interface, relying on low failure rate hardware and fast network connection. Google's MapReduce revolutionized large-scale analysis, enabling the processing of massive datasets on commodity hardware and cloud resources, providing transparent scalability and fault tolerance at the software level. Open source implementations of MapReduce include Apache Hadoop and the more recent Apache Spark. We developed a method to run existing docking-based screening software on distributed cloud resources, utilizing the MapReduce approach. We benchmarked our method, which is implemented in Apache Spark, docking a publicly available target receptor against [Formula: see text]2.2 M compounds. The performance experiments show a good parallel efficiency (87%) when running in a public cloud environment. Our method enables parallel Structure-based virtual screening on public cloud resources or commodity computer clusters. The degree of scalability that we achieve allows for trying out our method on relatively small libraries first and then to scale to larger libraries. Our implementation is named Spark-VS and it is freely available as open source from GitHub (https://github.com/mcapuccini/spark-vs).Graphical abstract.
A Rapid and Efficient Screening Method for Antibacterial Compound-Producing Bacteria.
Hettiarachchi, Sachithra; Lee, Su-Jin; Lee, Youngdeuk; Kwon, Young-Kyung; De Zoysa, Mahanama; Moon, Song; Jo, Eunyoung; Kim, Taeho; Kang, Do-Hyung; Heo, Soo-Jin; Oh, Chulhong
2017-08-28
Antibacterial compounds are widely used in the treatment of human and animal diseases. The overuse of antibiotics has led to a rapid rise in the prevalence of drug-resistant bacteria, making the development of new antibacterial compounds essential. This study focused on developing a fast and easy method for identifying marine bacteria that produce antibiotic compounds. Eight randomly selected marine target bacterial species ( Agrococcus terreus, Bacillus algicola, Mesoflavibacter zeaxanthinifaciens, Pseudoalteromonas flavipulchra, P. peptidolytica, P. piscicida, P. rubra , and Zunongwangia atlantica ) were tested for production of antibacterial compounds against four strains of test bacteria ( B. cereus, B. subtilis, Halomonas smyrnensis , and Vibrio alginolyticus ). Colony picking was used as the primary screening method. Clear zones were observed around colonies of P. flavipulchra, P. peptidolytica, P. piscicida , and P. rubra tested against B. cereus, B. subtilis , and H. smyrnensis . The efficiency of colony scraping and broth culture methods for antimicrobial compound extraction was also compared using a disk diffusion assay. P. peptidolytica, P. piscicida , and P. rubra showed antagonistic activity against H. smyrnensis, B. cereus , and B. subtilis , respectively, only in the colony scraping method. Our results show that colony picking and colony scraping are effective, quick, and easy methods of screening for antibacterial compound-producing bacteria.
Chunsuwan, Issarapa; Bunnag, Petch; Gronholm, Petra C; Lockwood Estrin, Georgia
2018-01-01
Introduction In low-income and middle-income countries, it is estimated that one in every three preschool-age children are failing to meet cognitive or socioemotional developmental milestones. Thailand has implemented a universal national developmental screening programme (DSPM) for young children to enable detection of developmental disorders and early intervention that can improve child health outcomes. DSPM implementation is being hampered by low attendance at follow-up appointments when children fail the initial screening. Methods Action research, using qualitative methods was conducted with 19 caregivers, 5 health workers and 1 chief at two Health Promotion Hospitals to explore the factors affecting attendance at follow-up appointments. Transcripts and notes were analysed using descriptive content analysis. Findings were then discussed with 48 health workers, managers, researchers and policymakers. Results The high workload of health workers during busy vaccination clinics, and inadequate materials prevented clear communication with caregivers about the screening, how to stimulate child development and the screening result. Caregivers, particularly grandparents, had a lack of understanding about how to stimulate child development, and did not fully understand failed screening results. Caregivers felt blamed for not stimulating their child’s development, and were either worried that their child was severely disabled, or they did not believe the screening result and therefore questioned its usefulness. This led to a lack of attendance at follow-up appointments. Conclusion Task-sharing, mobile health (mhealth), community outreach and targeted interventions for grandparent caregivers might increase awareness about child development and screening, and allow health workers more time to communicate effectively. Sharing best practices, communication training and mentoring of DSPM workers coupled with mhealth job aids could also improve caregiver attendance at follow-up. Engagement of caregivers in understanding the barriers to attendance at follow-up and engagement of stakeholders in the design and implementation of interventions is important to ensure their effectiveness. PMID:29564160
Electrical screening procedure for solid ionic conductors
NASA Technical Reports Server (NTRS)
Kautz, H. E.; Singer, J.; Fielder, W. L.; Fordyce, J. S.
1973-01-01
An electrical screening method has been developed for preliminary evaluation of polycrystalline specimens of candidates for use as solid ionic conductive electrolytes in batteries. The procedure measures dielectric loss and capacitance, from which are calculated an ac conductivity attributed provisionally to ions and an activation energy for that conductivity. Electronic conductivity is directly measured. The screening procedure applied to sodium beta-alumina yielded acceptable values for conductivity and activation energy.
Yu, Chaowen; Huang, Shuodan; Wang, Ming; Zhang, Juan; Liu, Hao; Yuan, Zhaojian; Wang, Xingbin; He, Xiaoyan; Wang, Jie; Zou, Lin
2017-02-10
Traditional methods for thalassemia screening are time-consuming and easily affected by cell hemolysis or hemoglobin degradation in stored blood samples. Tandem mass spectrometry (MS/MS) proved to be an effective technology for sickle cell disorders (SCD) screening. Here, we developed a novel MS/MS method for β-thalassemia screening from dried blood spots (DBS). Stable isotopic-labeled peptides were used as internal standards for quantification and calculation of the α:β-globin ratios. We used the α:β-globin ratio cutoffs to differentiate between normal individuals and patients with thalassemia. About 781 patients and 300 normal individuals were analyzed. The α:β-globin ratios showed significant difference between normal and β-thalassemia patients (P<0.01), particularly when the disease was homozygous or double heterozygous with another α- or β-thalassemia mutation. In the parallel study, all cases screened for suspected thalassemia from six hundred DBS samples by using this MS/MS method were successfully confirmed by genotyping. The intra-assay and inter-assay CVs of the ratios ranged from 2.4% to 3.9% and 4.7% to 7.1%, and there was no significant sample carryover or matrix effect for this MS/MS method. Combined with SCD screening, this MS/MS method could be used as a first-line screening assay for both structural and expression abnormalities of human hemoglobin. Traditional methods for thalassemia screening were depending on the structural integrity of tetramers and could be affected by hemolysis and degradation of whole blood samples, especially when stored. We used proteospecific peptides produced by the tryptic digestion of each globin to evaluate the production ratio between α- and β-globin chains, which turned out to be quite stable even when stored for more than two months. Though most of the peptides were specific to α-globin or β-globin, we only chose four most informative peptides and its stable isotopic-labeled peptides as internal standards for analysis, which could obtain a high accuracy. Currently, we are the first to address the application of MS/MS for thalassemia screening, when combined with SCD screening, this MS/MS method could be used as a first-line screening assay for both structural and expression abnormalities of human hemoglobin. Copyright © 2016. Published by Elsevier B.V.
Standardized assessment of infrared thermographic fever screening system performance
NASA Astrophysics Data System (ADS)
Ghassemi, Pejhman; Pfefer, Joshua; Casamento, Jon; Wang, Quanzeng
2017-03-01
Thermal modalities represent the only currently viable mass fever screening approach for outbreaks of infectious disease pandemics such as Ebola and SARS. Non-contact infrared thermometers (NCITs) and infrared thermographs (IRTs) have been previously used for mass fever screening in transportation hubs such as airports to reduce the spread of disease. While NCITs remain a more popular choice for fever screening in the field and at fixed locations, there has been increasing evidence in the literature that IRTs can provide greater accuracy in estimating core body temperature if appropriate measurement practices are applied - including the use of technically suitable thermographs. Therefore, the purpose of this study was to develop a battery of evaluation test methods for standardized, objective and quantitative assessment of thermograph performance characteristics critical to assessing suitability for clinical use. These factors include stability, drift, uniformity, minimum resolvable temperature difference, and accuracy. Two commercial IRT models were characterized. An external temperature reference source with high temperature accuracy was utilized as part of the screening thermograph. Results showed that both IRTs are relatively accurate and stable (<1% error of reading with stability of +/-0.05°C). Overall, results of this study may facilitate development of standardized consensus test methods to enable consistent and accurate use of IRTs for fever screening.
Zoorob, R; Anderson, R; Cefalu, C; Sidani, M
2001-03-15
Numerous medical organizations have developed cancer screening guidelines. Faced with the broad, and sometimes conflicting, range of recommendations for cancer screening, family physicians must determine the most reasonable and up-to-date method of screening. Major medical organizations have generally achieved consensus on screening guidelines for breast, cervical and colorectal cancer. For breast cancer screening in women ages 50 to 70, clinical breast examination and mammography are generally recommended every one or two years, depending on the medical organization. For cervical cancer screening, most organizations recommend a Papanicolaou test and pelvic examination at least every three years in patients between 20 and 65 years of age. Annual fecal occult blood testing along with flexible sigmoidoscopy at five-year to 10-year intervals is the standard recommendation for colorectal cancer screening in patients older than 50 years. Screening for prostate cancer remains a matter of debate. Some organizations recommend digital rectal examination and a serum prostate-specific antigen test for men older than 50 years, while others do not. In the absence of compelling evidence to indicate a high risk of endometrial cancer, lung cancer, oral cancer and ovarian cancer, almost no medical organizations have developed cancer screening guidelines for these types of cancer.
Colorectal Cancer Screening in Average Risk Populations: Evidence Summary.
Tinmouth, Jill; Vella, Emily T; Baxter, Nancy N; Dubé, Catherine; Gould, Michael; Hey, Amanda; Ismaila, Nofisat; McCurdy, Bronwen R; Paszat, Lawrence
2016-01-01
Introduction. The objectives of this systematic review were to evaluate the evidence for different CRC screening tests and to determine the most appropriate ages of initiation and cessation for CRC screening and the most appropriate screening intervals for selected CRC screening tests in people at average risk for CRC. Methods. Electronic databases were searched for studies that addressed the research objectives. Meta-analyses were conducted with clinically homogenous trials. A working group reviewed the evidence to develop conclusions. Results. Thirty RCTs and 29 observational studies were included. Flexible sigmoidoscopy (FS) prevented CRC and led to the largest reduction in CRC mortality with a smaller but significant reduction in CRC mortality with the use of guaiac fecal occult blood tests (gFOBTs). There was insufficient or low quality evidence to support the use of other screening tests, including colonoscopy, as well as changing the ages of initiation and cessation for CRC screening with gFOBTs in Ontario. Either annual or biennial screening using gFOBT reduces CRC-related mortality. Conclusion. The evidentiary base supports the use of FS or FOBT (either annual or biennial) to screen patients at average risk for CRC. This work will guide the development of the provincial CRC screening program.
A rapid screen for four corticosteroids in equine synovial fluid.
Agrawal, Karan; Ebel, Joseph G; Bischoff, Karyn
2014-06-01
Most antidoping method development in the equine industry has been for plasma and urine, though there has been recent interest in the analysis of synovial fluid for evidence of doping by intra-articular corticosteroid injection. Published methods for corticosteroid analysis in synovial fluid are primarily singleplex methods, do not screen for all corticosteroids of interest and are not adequately sensitive. The purpose of this study is to develop a rapid and sensitive liquid chromatography-tandem mass spectrometry (LC-MS-MS) screening method for the detection of four of the most common intra-articularly administered corticosteroids--betamethasone, methylprednisolone, methylprednisolone acetate and triamcinolone acetonide. Sample preparation consisted of protein precipitation followed by a basified liquid-liquid extraction. LC-MS-MS experiments consisted of a six-min isocratic separation using a Phenomenex Polar-RP stationary phase and a mobile phase consisting of 35% acetonitrile, 5 mM ammonium acetate and 0.1% formic acid in nanopure water. The detection system used was a triple quadrupole mass analyzer with thermospray ionization, and compounds were identified using selective reaction monitoring. The method was validated to the ISO/IEC 17025 standard, and real synovial fluid samples were analyzed to demonstrate the application of the method in an antidoping context. The method was highly selective for the four corticosteroids with limits of detection of 1-3 ng/mL. The extraction efficiency was 50-101%, and the matrix effects were 14-31%. These results indicate that the method is a rapid and sensitive screen for the four corticosteroids in equine synovial fluid, fit for purpose for equine antidoping assays.
2013-01-01
Background Despite progress in the development of combined antiretroviral therapies (cART), HIV infection remains a significant challenge for human health. Current problems of cART include multi-drug-resistant virus variants, long-term toxicity and enormous treatment costs. Therefore, the identification of novel effective drugs is urgently needed. Methods We developed a straightforward screening approach for simultaneously evaluating the sensitivity of multiple HIV gag-pol mutants to antiviral drugs in one assay. Our technique is based on multi-colour lentiviral self-inactivating (SIN) LeGO vector technology. Results We demonstrated the successful use of this approach for screening compounds against up to four HIV gag-pol variants (wild-type and three mutants) simultaneously. Importantly, the technique was adapted to Biosafety Level 1 conditions by utilising ecotropic pseudotypes. This allowed upscaling to a large-scale screening protocol exploited by pharmaceutical companies in a successful proof-of-concept experiment. Conclusions The technology developed here facilitates fast screening for anti-HIV activity of individual agents from large compound libraries. Although drugs targeting gag-pol variants were used here, our approach permits screening compounds that target several different, key cellular and viral functions of the HIV life-cycle. The modular principle of the method also allows the easy exchange of various mutations in HIV sequences. In conclusion, the methodology presented here provides a valuable new approach for the identification of novel anti-HIV drugs. PMID:23286882
EVALUATION OF FADROZOLE AS AN ENDOCRINE DISRUPTOR IN FATHEAD MINNOW (PIMEPHALES PROMELAS)
The EPA has received a legislative mandate to develop and implement standardized screening and testing methods to identify and assess potential endocrine disrupting chemicals (EDCs). The objective of this research was to evaluate a short-term EDC screening/testing assay which ass...
77 FR 16846 - Published Privacy Impact Assessments on the Web
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-22
... Security Advanced Research Projects Agency (HSARPA), S&T Directorate seeks to develop physiological and behavioral screening technologies that will enable security officials to test the effectiveness of current... FAST research is adding a new type of research, the Passive Methods for Precision Behavioral Screening...
New methods are needed to screen thousands of environmental chemicals for toxicity, including developmental neurotoxicity. In vitro, cell-based assays that model key cellular events have been proposed for high throughput screening of chemicals for developmental neurotoxicity. Whi...
Screening of fluoroquinolone residues in caprine milk using a 5-kg luminescence photometer
USDA-ARS?s Scientific Manuscript database
A terbium-sensitized luminescence (TSL) method was developed to screen presence of residues of four fluoroquinolones (FQ) registered in caprine milk in the European Union: enrofloxacin, ciprofloxacin, flumequine, and danofloxacin. After extraction in McIlvaine buffer and SPE cleanup, TSL was measure...
Advanced Millimeter-Wave Imaging Enhances Security Screening
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sheen, David M.; Bernacki, Bruce E.; McMakin, Douglas L.
2012-01-12
Millimeter-wave imaging is rapidly gaining acceptance for passenger screening at airports and other secured facilities. This paper details a number of techniques developed over the last several years including novel image reconstruction and display techniques, polarimetric imaging techniques, array switching schemes, as well as high frequency high bandwidth techniques. Implementation of some of these methods will increase the cost and complexity of the mm-wave security portal imaging systems. RF photonic methods may provide new solutions to the design and development of the sequentially switched linear mm-wave arrays that are the key element in the mm-wave portal imaging systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jakubowski, E.M.; Borland, M.M.; Norris, L.
1995-06-01
The U.S. Army Edgewood Research, Development and Engineering Center, the U.S. Army Aberdeen Proving Ground Support Activity, Directorate of Safety, Health and the Environment and SciTech Services Inc., an independent contractor, have developed an approach for screening environmental samples for the presence of chemical warfare agents. Since 1918, the Edgewood area of Aberdeen Proving Ground has been a research and testing ground for toxic agent compounds. Since these materials are considered highly toxic, screening for their presence in environmental samples is necessary for safe shipment to contract laboratories for testing by EPA guidelines. The screening ensures worker safety and maintainsmore » U.S. Army standards for transportation of materials potentially contaminated with chemical warfare agents. This paper describes the screening methodology.« less
Yoshii, Yukie; Furukawa, Takako; Waki, Atsuo; Okuyama, Hiroaki; Inoue, Masahiro; Itoh, Manabu; Zhang, Ming-Rong; Wakizaka, Hidekatsu; Sogawa, Chizuru; Kiyono, Yasushi; Yoshii, Hiroshi; Fujibayashi, Yasuhisa; Saga, Tsuneo
2015-05-01
Anti-cancer drug development typically utilizes high-throughput screening with two-dimensional (2D) cell culture. However, 2D culture induces cellular characteristics different from tumors in vivo, resulting in inefficient drug development. Here, we report an innovative high-throughput screening system using nanoimprinting 3D culture to simulate in vivo conditions, thereby facilitating efficient drug development. We demonstrated that cell line-based nanoimprinting 3D screening can more efficiently select drugs that effectively inhibit cancer growth in vivo as compared to 2D culture. Metabolic responses after treatment were assessed using positron emission tomography (PET) probes, and revealed similar characteristics between the 3D spheroids and in vivo tumors. Further, we developed an advanced method to adopt cancer cells from patient tumor tissues for high-throughput drug screening with nanoimprinting 3D culture, which we termed Cancer tissue-Originated Uniformed Spheroid Assay (COUSA). This system identified drugs that were effective in xenografts of the original patient tumors. Nanoimprinting 3D spheroids showed low permeability and formation of hypoxic regions inside, similar to in vivo tumors. Collectively, the nanoimprinting 3D culture provides easy-handling high-throughput drug screening system, which allows for efficient drug development by mimicking the tumor environment. The COUSA system could be a useful platform for drug development with patient cancer cells. Copyright © 2015 Elsevier Ltd. All rights reserved.
Lake, Amelia J; Browne, Jessica L; Abraham, Charles; Tumino, Dee; Hines, Carolyn; Rees, Gwyneth; Speight, Jane
2018-05-31
Young adults (18-39 years) with type 2 diabetes are at risk of early development and rapid progression of diabetic retinopathy, a leading cause of vision loss and blindness in working-age adults. Retinal screening is key to the early detection of diabetic retinopathy, with risk of vision loss significantly reduced by timely treatment thereafter. Despite this, retinal screening rates are low among this at-risk group. The objective of this study was to develop a theoretically-grounded, evidence-based retinal screening promotion leaflet, tailored to young adults with type 2 diabetes. Utilising the six steps of Intervention Mapping, our multidisciplinary planning team conducted a mixed-methods needs assessment (Step 1); identified modifiable behavioural determinants of screening behaviour and constructed a matrix of change objectives (Step 2); designed, reviewed and debriefed leaflet content with stakeholders (Steps 3 and 4); and developed program implementation and evaluation plans (Steps 5 and 6). Step 1 included in-depth qualitative interviews (N = 10) and an online survey that recruited a nationally-representative sample (N = 227), both informed by literature review. The needs assessment highlighted the crucial roles of knowledge (about diabetic retinopathy and screening), perception of personal risk, awareness of the approval of significant others and engagement with healthcare team, on retinal screening intentions and uptake. In Step 2, we selected five modifiable behavioural determinants to be targeted: knowledge, attitudes, normative beliefs, intention, and behavioural skills. In Steps 3 and 4, the "Who is looking after your eyes?" leaflet was developed, containing persuasive messages targeting each determinant and utilising engaging, cohort-appropriate imagery. In Steps 5 and 6, we planned Statewide implementation and designed a randomised controlled trial to evaluate the leaflet. This research provides an example of a systematic, evidence-based approach to the development of a simple health intervention designed to promote uptake of screening in accordance with national guidelines. The methods and findings illustrate how Intervention Mapping can be employed to develop tailored retinal screening promotion materials for specific priority populations. This paper has implications for future program planners and is intended to assist those wishing to use Intervention Mapping to create similar theoretically-driven, tailored resources.
Camattari, Andrea; Weinhandl, Katrin; Gudiminchi, Rama K
2014-01-01
The methylotrophic yeast Pichia pastoris is becoming one of the favorite industrial workhorses for protein expression. Due to the widespread use of integration vectors, which generates significant clonal variability, screening methods allowing assaying hundreds of individual clones are of particular importance. Here we describe methods to detect and analyze protein expression, developed in a 96-well format for high-throughput screening of recombinant P. pastoris strains. The chapter covers essentially three common scenarios: (1) an enzymatic assay for proteins expressed in the cell cytoplasm, requiring cell lysis; (2) a whole-cell assay for a fungal cytochrome P450; and (3) a nonenzymatic assay for detection and quantification of tagged protein secreted into the supernatant.
Paveley, Ross A.; Mansour, Nuha R.; Hallyburton, Irene; Bleicher, Leo S.; Benn, Alex E.; Mikic, Ivana; Guidi, Alessandra; Gilbert, Ian H.; Hopkins, Andrew L.; Bickle, Quentin D.
2012-01-01
Sole reliance on one drug, Praziquantel, for treatment and control of schistosomiasis raises concerns about development of widespread resistance, prompting renewed interest in the discovery of new anthelmintics. To discover new leads we designed an automated label-free, high content-based, high throughput screen (HTS) to assess drug-induced effects on in vitro cultured larvae (schistosomula) using bright-field imaging. Automatic image analysis and Bayesian prediction models define morphological damage, hit/non-hit prediction and larval phenotype characterization. Motility was also assessed from time-lapse images. In screening a 10,041 compound library the HTS correctly detected 99.8% of the hits scored visually. A proportion of these larval hits were also active in an adult worm ex-vivo screen and are the subject of ongoing studies. The method allows, for the first time, screening of large compound collections against schistosomes and the methods are adaptable to other whole organism and cell-based screening by morphology and motility phenotyping. PMID:22860151
Li, Z; Chang, S; Lin, L; Li, Y; An, Q
2011-08-01
1-Aminocyclopropane-1-carboxylate (ACC) deaminase activity is an efficient marker for bacteria to promote plant growth by lowering ethylene levels in plants. We aim to develop a method for rapidly screening bacteria containing ACC deaminase, based on a colorimetric ninhydrin assay of ACC. A reliable colorimetric ninhydrin assay was developed to quantify ACC using heat-resistant polypropylene chimney-top 96-well PCR plates, having the wells evenly heated in boiling water, preventing accidental contamination from boiling water and limiting evaporation. With this method to measure bacterial consumption of ACC, 44 ACC-utilizing bacterial isolates were rapidly screened out from 311 bacterial isolates that were able to grow on minimal media containing ACC as the sole nitrogen source. The 44 ACC-utilizing bacterial isolates showed ACC deaminase activities and belonged to the genus Burkholderia, Pseudomonas or Herbaspirillum. Determination of bacterial ACC consumption by the PCR-plate ninhydrin-ACC assay is a rapid and efficient method for screening bacteria containing ACC deaminase from a large number of bacterial isolates. The PCR-plate ninhydrin-ACC assay extends the utility of the ninhydrin reaction and enables a rapid screening of bacteria containing ACC deaminase from large numbers of bacterial isolates. © 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yagnik, Gargey B.
The main goal of the presented research is development of nanoparticle based matrix-assisted laser desorption ionization-mass spectrometry (MALDI-MS). This dissertation includes the application of previously developed data acquisition methods, development of novel sample preparation methods, application and comparison of novel nanoparticle matrices, and comparison of two nanoparticle matrix application methods for MALDI-MS and MALDI-MS imaging.
Rafii, Forough; Rahimparvar, Seyedeh Fatemeh Vasegh; Mehrdad, Neda; Keramat, Afsaneh
2017-01-01
Risk of developing type 2 diabetes is increased in women with previous gestational diabetes mellitus (GDM). Postpartum glycemic screening is recommended in women with recent GDM. But this screening rate is low and the reasons are unclear. The aim of this study was to explore the experiences of Iranian women with recent GDM on barriers of postpartum screening for diabetes. This qualitative study was conducted in Tehran, Iran in 2016. Semi-structured interview was used for data collection. 22 women with recent GDM were interviewed. These women gave birth in Tehran hospitals at a minimum of 6 months before interview. The missed screening defined as not attending to laboratory for Fasting Blood Sugar and/or Oral Glucose Tolerance Test, 6 week to 6 month after their child birthing. The data was analyzed by content analysis method. Themes and sub-themes that illustrated the barriers to postpartum diabetes screening were: inadequate education (about developing diabetes in the future, implementation of the screening, and glucometer validity in diagnosis of diabetes), perceiving the screening as difficult (feeling comfortable with the glucometer, poor laboratory conditions, issues related to the baby/babies, and financial problems), improper attitudes toward the screening (unwilling to get diagnosed, not giving priority to oneself, having false beliefs) and procrastination (gap to intention and action, self-deception and self-regulation failure). Women with recent GDM reported several barriers for postpartum diabetes screening. This study help to develop the evidence-based interventions for improving this screening rate.
Kittelmann, Jörg; Ottens, Marcel; Hubbuch, Jürgen
2015-04-15
High-throughput batch screening technologies have become an important tool in downstream process development. Although continuative miniaturization saves time and sample consumption, there is yet no screening process described in the 384-well microplate format. Several processes are established in the 96-well dimension to investigate protein-adsorbent interactions, utilizing between 6.8 and 50 μL resin per well. However, as sample consumption scales with resin volumes and throughput scales with experiments per microplate, they are limited in costs and saved time. In this work, a new method for in-well resin quantification by optical means, applicable in the 384-well format, and resin volumes as small as 0.1 μL is introduced. A HTS batch isotherm process is described, utilizing this new method in combination with optical sample volume quantification for screening of isotherm parameters in 384-well microplates. Results are qualified by confidence bounds determined by bootstrap analysis and a comprehensive Monte Carlo study of error propagation. This new approach opens the door to a variety of screening processes in the 384-well format on HTS stations, higher quality screening data and an increase in throughput. Copyright © 2015 Elsevier B.V. All rights reserved.
Semiautomated TaqMan PCR screening of GMO labelled samples for (unauthorised) GMOs.
Scholtens, Ingrid M J; Molenaar, Bonnie; van Hoof, Richard A; Zaaijer, Stephanie; Prins, Theo W; Kok, Esther J
2017-06-01
In most countries, systems are in place to analyse food products for the potential presence of genetically modified organisms (GMOs), to enforce labelling requirements and to screen for the potential presence of unauthorised GMOs. With the growing number of GMOs on the world market, a larger diversity of methods is required for informative analyses. In this paper, the specificity of an extended screening set consisting of 32 screening methods to identify different crop species (endogenous genes) and GMO elements was verified against 59 different GMO reference materials. In addition, a cost- and time-efficient strategy for DNA isolation, screening and identification is presented. A module for semiautomated analysis of the screening results and planning of subsequent event-specific tests for identification has been developed. The Excel-based module contains information on the experimentally verified specificity of the element methods and of the EU authorisation status of the GMO events. If a detected GMO element cannot be explained by any of the events as identified in the same sample, this may indicate the presence of an unknown unauthorised GMO that may not yet have been assessed for its safety for humans, animals or the environment.
Takabatake, Reona; Koiwa, Tomohiro; Kasahara, Masaki; Takashima, Kaori; Futo, Satoshi; Minegishi, Yasutaka; Akiyama, Hiroshi; Teshima, Reiko; Oguchi, Taichi; Mano, Junichi; Furui, Satoshi; Kitta, Kazumi
2011-01-01
To reduce the cost and time required to routinely perform the genetically modified organism (GMO) test, we developed a duplex quantitative real-time PCR method for a screening analysis simultaneously targeting an event-specific segment for GA21 and Cauliflower Mosaic Virus 35S promoter (P35S) segment [Oguchi et al., J. Food Hyg. Soc. Japan, 50, 117-125 (2009)]. To confirm the validity of the method, an interlaboratory collaborative study was conducted. In the collaborative study, conversion factors (Cfs), which are required to calculate the GMO amount (%), were first determined for two real-time PCR instruments, the ABI PRISM 7900HT and the ABI PRISM 7500. A blind test was then conducted. The limit of quantitation for both GA21 and P35S was estimated to be 0.5% or less. The trueness and precision were evaluated as the bias and reproducibility of the relative standard deviation (RSD(R)). The determined bias and RSD(R) were each less than 25%. We believe the developed method would be useful for the practical screening analysis of GM maize.
Manoharan, Prabu; Ghoshal, Nanda
2018-05-01
Traditional structure-based virtual screening method to identify drug-like small molecules for BACE1 is so far unsuccessful. Location of BACE1, poor Blood Brain Barrier permeability and P-glycoprotein (Pgp) susceptibility of the inhibitors make it even more difficult. Fragment-based drug design method is suitable for efficient optimization of initial hit molecules for target like BACE1. We have developed a fragment-based virtual screening approach to identify/optimize the fragment molecules as a starting point. This method combines the shape, electrostatic, and pharmacophoric features of known fragment molecules, bound to protein conjugate crystal structure, and aims to identify both chemically and energetically feasible small fragment ligands that bind to BACE1 active site. The two top-ranked fragment hits were subjected for a 53 ns MD simulation. Principle component analysis and free energy landscape analysis reveal that the new ligands show the characteristic features of established BACE1 inhibitors. The potent method employed in this study may serve for the development of potential lead molecules for BACE1-directed Alzheimer's disease therapeutics.
Ogunyemi, Omolola; Teklehaimanot, Senait; Patty, Lauren; Moran, Erin; George, Sheba
2013-01-01
Introduction Screening guidelines for diabetic patients recommend yearly eye examinations to detect diabetic retinopathy and other forms of diabetic eye disease. However, annual screening rates for retinopathy in US urban safety net settings remain low. Methods Using data gathered from a study of teleretinal screening in six urban safety net clinics, we assessed whether predictive modeling could be of value in identifying patients at risk of developing retinopathy. We developed and examined the accuracy of two predictive modeling approaches for diabetic retinopathy in a sample of 513 diabetic individuals, using routinely available clinical variables from retrospective medical record reviews. Bayesian networks and radial basis function (neural) networks were learned using ten-fold cross-validation. Results The predictive models were modestly predictive with the best model having an AUC of 0.71. Discussion Using routinely available clinical variables to predict patients at risk of developing retinopathy and to target them for annual eye screenings may be of some usefulness to safety net clinics. PMID:23920536
Lim, Maria A; Louie, Brenton; Ford, Daniel; Heath, Kyle; Cha, Paulyn; Betts-Lacroix, Joe; Lum, Pek Yee; Robertson, Timothy L; Schaevitz, Laura
2017-01-01
Despite a broad spectrum of anti-arthritic drugs currently on the market, there is a constant demand to develop improved therapeutic agents. Efficient compound screening and rapid evaluation of treatment efficacy in animal models of rheumatoid arthritis (RA) can accelerate the development of clinical candidates. Compound screening by evaluation of disease phenotypes in animal models facilitates preclinical research by enhancing understanding of human pathophysiology; however, there is still a continuous need to improve methods for evaluating disease. Current clinical assessment methods are challenged by the subjective nature of scoring-based methods, time-consuming longitudinal experiments, and the requirement for better functional readouts with relevance to human disease. To address these needs, we developed a low-touch, digital platform for phenotyping preclinical rodent models of disease. As a proof-of-concept, we utilized the rat collagen-induced arthritis (CIA) model of RA and developed the Digital Arthritis Index (DAI), an objective and automated behavioral metric that does not require human-animal interaction during the measurement and calculation of disease parameters. The DAI detected the development of arthritis similar to standard in vivo methods, including ankle joint measurements and arthritis scores, as well as demonstrated a positive correlation to ankle joint histopathology. The DAI also determined responses to multiple standard-of-care (SOC) treatments and nine repurposed compounds predicted by the SMarTR TM Engine to have varying degrees of impact on RA. The disease profiles generated by the DAI complemented those generated by standard methods. The DAI is a highly reproducible and automated approach that can be used in-conjunction with standard methods for detecting RA disease progression and conducting phenotypic drug screens.
Public stated preferences and predicted uptake for genome-based colorectal cancer screening
2014-01-01
Background Emerging developments in nanomedicine allow the development of genome-based technologies for non-invasive and individualised screening for diseases such as colorectal cancer. The main objective of this study was to measure user preferences for colorectal cancer screening using a nanopill. Methods A discrete choice experiment was used to estimate the preferences for five competing diagnostic techniques including the nanopill and iFOBT. Alternative screening scenarios were described using five attributes namely: preparation involved, sensitivity, specificity, complication rate and testing frequency. Fourteen random and two fixed choice tasks, each consisting of three alternatives, were offered to 2225 individuals. Data were analysed using the McFadden conditional logit model. Results Thirteen hundred and fifty-six respondents completed the questionnaire. The most important attributes (and preferred levels) were the screening technique (nanopill), sensitivity (100%) and preparation (no preparation). Stated screening uptake for the nanopill was 79%, compared to 76% for iFOBT. In the case of screening with the nanopill, the percentage of people preferring not to be screened would be reduced from 19.2% (iFOBT) to 16.7%. Conclusions Although the expected benefits of nanotechnology based colorectal cancer screening are improved screening uptake, assuming more accurate test results and less preparation involved, the relative preference of the nanopill is only slightly higher than the iFOBT. Estimating user preferences during the development of diagnostic technologies could be used to identify relative performance, including perceived benefits and harms compared to competitors allowing for significant changes to be made throughout the process of development. PMID:24642027
Development and application of a general plasmid reference material for GMO screening.
Wu, Yuhua; Li, Jun; Wang, Yulei; Li, Xiaofei; Li, Yunjing; Zhu, Li; Li, Jun; Wu, Gang
The use of analytical controls is essential when performing GMO detection through screening tests. Additionally, the presence of taxon-specific sequences is analyzed mostly for quality control during GMO detection. In this study, 11 commonly used genetic elements involving three promoters (P-35S, P-FMV35S and P-NOS), four marker genes (Bar, NPTII, HPT and Pmi), and four terminators (T-NOS, T-35S, T-g7 and T-e9), together with the reference gene fragments from six major crops of maize, soybean, rapeseed, rice, cotton and wheat, were co-integrated into the same single plasmid to construct a general reference plasmid pBI121-Screening. The suitability test of pBI121-Screening plasmid as reference material indicated that the non-target sequence on the pBI121-Screening plasmid did not affect the PCR amplification efficiencies of screening methods and taxon-specific methods. The sensitivity of screening and taxon-specific assays ranged from 5 to 10 copies of pBI121-Screening plasmid, meeting the sensitivity requirement of GMO detection. The construction of pBI121-Screening solves the lack of a general positive control for screening tests, thereby reducing the workload and cost of preparing a plurality of the positive control. Copyright © 2016 Elsevier B.V. All rights reserved.
Suba, E J; Nguyen, C H; Nguyen, B D; Raab, S S
2001-03-01
Cervical carcinoma is the leading cause of cancer-related death among women in the developing world. The absence of cervical screening in Vietnam and other developing countries is due in large part to the perceived expense of implementing Papanicolaou cytology screening services, although, to the authors' knowledge, the cost-effectiveness of establishing such services has never been studied in a developing country. Using decision analytic methods, the authors assessed cost-effectiveness of Pap screening from a societal perspective in Vietnam, the world's 9th most populous developing country (estimated 1999 population, 79 million). Outcomes measured included life expectancy, cervical carcinoma incidence, cost per woman, and cost-effectiveness. Total costs to establish a nationwide 5-year interval Pap screening program in Vietnam will average less than $148,400 annually during the 10-year time period assumed necessary to develop the program and may be considerably lower if only high risk geographic areas are targeted. Maintenance costs will average less than $0.092 annually per woman in the target screening population. Assuming 70% program participation, cervical carcinoma incidence will decrease from 26 in 100,000 to 14.8 in 100,000, and cost-effectiveness will be $725 per discounted life-year. Several assumptions used in this analysis constitute biases against the effectiveness of Pap screening, which in reality may be significantly more cost-effective than reported here. Contrary to widespread belief, Pap screening in developing countries such as Vietnam is extraordinarily inexpensive and appears to be cost-effective. Because prospects are uncertain regarding useful alternatives to the Pap test, the evidence-based argument for establishing conventional Pap screening services in developing countries such as Vietnam is compelling. Population-based conventional Pap screening services have been established de novo in Vietnam and are now operational. Copyright 2001 American Cancer Society.
IDIOS: An innovative index for evaluating dental imaging-based osteoporosis screening indices
Halboub, Esam; Almashraqi, Abeer Abdulkareem; Khattab, Razan; Al Haffar, Iyad
2016-01-01
Purpose The goal of this study was to develop a new index as an objective reference for evaluating current and newly developed indices used for osteoporosis screening based on dental images. Its name; IDIOS, stands for Index of Dental-imaging Indices of Osteoporosis Screening. Materials and Methods A comprehensive PubMed search was conducted to retrieve studies on dental imaging-based indices for osteoporosis screening. The results of the eligible studies, along with other relevant criteria, were used to develop IDIOS, which has scores ranging from 0 (0%) to 15 (100%). The indices presented in the studies we included were then evaluated using IDIOS. Results The 104 studies that were included utilized 24, 4, and 9 indices derived from panoramic, periapical, and computed tomographic/cone-beam computed tomographic techniques, respectively. The IDIOS scores for these indices ranged from 0 (0%) to 11.75 (78.32%). Conclusion IDIOS is a valuable reference index that facilitates the evaluation of other dental imaging-based osteoporosis screening indices. Furthermore, IDIOS can be utilized to evaluate the accuracy of newly developed indices. PMID:27672615
Hart, Dennis L; Werneke, Mark W; George, Steven Z; Matheson, James W; Wang, Ying-Chih; Cook, Karon F; Mioduski, Jerome E; Choi, Seung W
2009-08-01
Screening people for elevated levels of fear-avoidance beliefs is uncommon, but elevated levels of fear could worsen outcomes. Developing short screening tools might reduce the data collection burden and facilitate screening, which could prompt further testing or management strategy modifications to improve outcomes. The purpose of this study was to develop efficient yet accurate screening methods for identifying elevated levels of fear-avoidance beliefs regarding work or physical activities in people receiving outpatient rehabilitation. A secondary analysis of data collected prospectively from people with a variety of common neuromusculoskeletal diagnoses was conducted. Intake Fear-Avoidance Beliefs Questionnaire (FABQ) data were collected from 17,804 people who had common neuromusculoskeletal conditions and were receiving outpatient rehabilitation in 121 clinics in 26 states (in the United States). Item response theory (IRT) methods were used to analyze the FABQ data, with particular emphasis on differential item functioning among clinically logical groups of subjects, and to identify screening items. The accuracy of screening items for identifying subjects with elevated levels of fear was assessed with receiver operating characteristic analyses. Three items for fear of physical activities and 10 items for fear of work activities represented unidimensional scales with adequate IRT model fit. Differential item functioning was negligible for variables known to affect functional status outcomes: sex, age, symptom acuity, surgical history, pain intensity, condition severity, and impairment. Items that provided maximum information at the median for the FABQ scales were selected as screening items to dichotomize subjects by high versus low levels of fear. The accuracy of the screening items was supported for both scales. This study represents a retrospective analysis, which should be replicated using prospective designs. Future prospective studies should assess the reliability and validity of using one FABQ item to screen people for high levels of fear-avoidance beliefs. The lack of differential item functioning in the FABQ scales in the sample tested in this study suggested that FABQ screening could be useful in routine clinical practice and allowed the development of single-item screening for fear-avoidance beliefs that accurately identified subjects with elevated levels of fear. Because screening was accurate and efficient, single IRT-based FABQ screening items are recommended to facilitate improved evaluation and care of heterogeneous populations of people receiving outpatient rehabilitation.
Cystic Fibrosis Colorectal Cancer Screening Consensus Recommendations.
Hadjiliadis, Denis; Khoruts, Alexander; Zauber, Ann G; Hempstead, Sarah E; Maisonneuve, Patrick; Lowenfels, Albert B
2018-02-01
Improved therapy has substantially increased survival of persons with cystic fibrosis (CF). But the risk of colorectal cancer (CRC) in adults with CF is 5-10 times greater compared to the general population, and 25-30 times greater in CF patients after an organ transplantation. To address this risk, the CF Foundation convened a multi-stakeholder task force to develop CRC screening recommendations. The 18-member task force consisted of experts including pulmonologists, gastroenterologists, a social worker, nurse coordinator, surgeon, epidemiologist, statistician, CF adult, and a parent. The committee comprised 3 workgroups: Cancer Risk, Transplant, and Procedure and Preparation. A guidelines specialist at the CF Foundation conducted an evidence synthesis February-March 2016 based on PubMed literature searches. Task force members conducted additional independent searches. A total of 1159 articles were retrieved. After initial screening, the committee read 198 articles in full and analyzed 123 articles to develop recommendation statements. An independent decision analysis evaluating the benefits of screening relative to harms and resources required was conducted by the Department of Public Health at Erasmus Medical Center, Netherlands using the Microsimulation Screening Analysis model from the Cancer Innervation and Surveillance Modeling Network. The task force included recommendation statements in the final guideline only if they reached an 80% acceptance threshold. The task force makes 10 CRC screening recommendations that emphasize shared, individualized decision-making and familiarity with CF-specific gastrointestinal challenges. We recommend colonoscopy as the preferred screening method, initiation of screening at age 40 years, 5-year re-screening and 3-year surveillance intervals (unless shorter interval is indicated by individual findings), and a CF-specific intensive bowel preparation. Organ transplant recipients with CF should initiate CRC screening at age 30 years within 2 years of the transplantation because of the additional risk for colon cancer associated with immunosuppression. These recommendations aim to help CF adults, families, primary care physicians, gastroenterologists, and CF and transplantation centers address the issue of CRC screening. They differ from guidelines developed for the general population with respect to the recommended age of screening initiation, screening method, preparation, and the interval for repeat screening and surveillance. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.
USDA-ARS?s Scientific Manuscript database
A rapid luminescence method was developed to screen residues of enrofloxacin (ENRO) and its metabolite, ciprofloxacin (CIPRO), in swine liver. Target analytes were extracted in acetonitrile-2.5% trifluoroacetic acid-NaCl, cleaned up by dispersive liquid-liquid microextraction (DLLME), and finally de...
USDA-ARS?s Scientific Manuscript database
A method has been developed for screening glyceollins and their metabolites based upon precursor ion scanning. Under higher-energy collision conditions, employing a triple quadrupole mass spectrometer in the negative ion mode, deprotonated glyceollin precursors yield a diagnostic radical product ion...
A high-throughput method for the detection of homoeologous gene deletions in hexaploid wheat
2010-01-01
Background Mutational inactivation of plant genes is an essential tool in gene function studies. Plants with inactivated or deleted genes may also be exploited for crop improvement if such mutations/deletions produce a desirable agronomical and/or quality phenotype. However, the use of mutational gene inactivation/deletion has been impeded in polyploid plant species by genetic redundancy, as polyploids contain multiple copies of the same genes (homoeologous genes) encoded by each of the ancestral genomes. Similar to many other crop plants, bread wheat (Triticum aestivum L.) is polyploid; specifically allohexaploid possessing three progenitor genomes designated as 'A', 'B', and 'D'. Recently modified TILLING protocols have been developed specifically for mutation detection in wheat. Whilst extremely powerful in detecting single nucleotide changes and small deletions, these methods are not suitable for detecting whole gene deletions. Therefore, high-throughput methods for screening of candidate homoeologous gene deletions are needed for application to wheat populations generated by the use of certain mutagenic agents (e.g. heavy ion irradiation) that frequently generate whole-gene deletions. Results To facilitate the screening for specific homoeologous gene deletions in hexaploid wheat, we have developed a TaqMan qPCR-based method that allows high-throughput detection of deletions in homoeologous copies of any gene of interest, provided that sufficient polymorphism (as little as a single nucleotide difference) amongst homoeologues exists for specific probe design. We used this method to identify deletions of individual TaPFT1 homoeologues, a wheat orthologue of the disease susceptibility and flowering regulatory gene PFT1 in Arabidopsis. This method was applied to wheat nullisomic-tetrasomic lines as well as other chromosomal deletion lines to locate the TaPFT1 gene to the long arm of chromosome 5. By screening of individual DNA samples from 4500 M2 mutant wheat lines generated by heavy ion irradiation, we detected multiple mutants with deletions of each TaPFT1 homoeologue, and confirmed these deletions using a CAPS method. We have subsequently designed, optimized, and applied this method for the screening of homoeologous deletions of three additional wheat genes putatively involved in plant disease resistance. Conclusions We have developed a method for automated, high-throughput screening to identify deletions of individual homoeologues of a wheat gene. This method is also potentially applicable to other polyploidy plants. PMID:21114819
Stanley, Sarah A; Hung, Deborah T
2009-12-16
Loss-of-function genetic screens have facilitated great strides in our understanding of the biology of model organisms but have not been possible in diploid human cells. A recent report by Brummelkamp's group in Science describes the use of insertional mutagenesis to generate loss-of-function alleles in a largely haploid human cell line and demonstrates the versatility of this method in screens designed to investigate the host/pathogen interaction. This approach has strengths that are complementary to existing strategies and will facilitate progress toward a systems-level understanding of infectious disease and ultimately the development of new therapeutics.
Godin, Katelyn; Stapleton, Jackie; Kirkpatrick, Sharon I; Hanning, Rhona M; Leatherdale, Scott T
2015-10-22
Grey literature is an important source of information for large-scale review syntheses. However, there are many characteristics of grey literature that make it difficult to search systematically. Further, there is no 'gold standard' for rigorous systematic grey literature search methods and few resources on how to conduct this type of search. This paper describes systematic review search methods that were developed and applied to complete a case study systematic review of grey literature that examined guidelines for school-based breakfast programs in Canada. A grey literature search plan was developed to incorporate four different searching strategies: (1) grey literature databases, (2) customized Google search engines, (3) targeted websites, and (4) consultation with contact experts. These complementary strategies were used to minimize the risk of omitting relevant sources. Since abstracts are often unavailable in grey literature documents, items' abstracts, executive summaries, or table of contents (whichever was available) were screened. Screening of publications' full-text followed. Data were extracted on the organization, year published, who they were developed by, intended audience, goal/objectives of document, sources of evidence/resources cited, meals mentioned in the guidelines, and recommendations for program delivery. The search strategies for identifying and screening publications for inclusion in the case study review was found to be manageable, comprehensive, and intuitive when applied in practice. The four search strategies of the grey literature search plan yielded 302 potentially relevant items for screening. Following the screening process, 15 publications that met all eligibility criteria remained and were included in the case study systematic review. The high-level findings of the case study systematic review are briefly described. This article demonstrated a feasible and seemingly robust method for applying systematic search strategies to identify web-based resources in the grey literature. The search strategy we developed and tested is amenable to adaptation to identify other types of grey literature from other disciplines and answering a wide range of research questions. This method should be further adapted and tested in future research syntheses.
A Novel Quantum Dots-Based Point of Care Test for Syphilis
NASA Astrophysics Data System (ADS)
Yang, Hao; Li, Ding; He, Rong; Guo, Qin; Wang, Kan; Zhang, Xueqing; Huang, Peng; Cui, Daxiang
2010-05-01
One-step lateral flow test is recommended as the first line screening of syphilis for primary healthcare settings in developing countries. However, it generally shows low sensitivity. We describe here the development of a novel fluorescent POC (Point Of Care) test method to be used for screening for syphilis. The method was designed to combine the rapidness of lateral flow test and sensitiveness of fluorescent method. 50 syphilis-positive specimens and 50 healthy specimens conformed by Treponema pallidum particle agglutination (TPPA) were tested with Quantum Dot-labeled and colloidal gold-labeled lateral flow test strips, respectively. The results showed that both sensitivity and specificity of the quantum dots-based method reached up to 100% (95% confidence interval [CI], 91-100%), while those of the colloidal gold-based method were 82% (95% CI, 68-91%) and 100% (95% CI, 91-100%), respectively. In addition, the naked-eye detection limit of quantum dot-based method could achieve 2 ng/ml of anti-TP47 polyclonal antibodies purified by affinity chromatography with TP47 antigen, which was tenfold higher than that of colloidal gold-based method. In conclusion, the quantum dots were found to be suitable for labels of lateral flow test strip. Its ease of use, sensitiveness and low cost make it well-suited for population-based on-the-site syphilis screening.
NASA Astrophysics Data System (ADS)
Kortagere, Sandhya; Welsh, William J.
2006-12-01
G-protein coupled receptors (GPCRs) comprise a large superfamily of proteins that are targets for nearly 50% of drugs in clinical use today. In the past, the use of structure-based drug design strategies to develop better drug candidates has been severely hampered due to the absence of the receptor's three-dimensional structure. However, with recent advances in molecular modeling techniques and better computing power, atomic level details of these receptors can be derived from computationally derived molecular models. Using information from these models coupled with experimental evidence, it has become feasible to build receptor pharmacophores. In this study, we demonstrate the use of the Hybrid Structure Based (HSB) method that can be used effectively to screen and identify prospective ligands that bind to GPCRs. Essentially; this multi-step method combines ligand-based methods for building enriched libraries of small molecules and structure-based methods for screening molecules against the GPCR target. The HSB method was validated to identify retinal and its analogues from a random dataset of ˜300,000 molecules. The results from this study showed that the 9 top-ranking molecules are indeed analogues of retinal. The method was also tested to identify analogues of dopamine binding to the dopamine D2 receptor. Six of the ten top-ranking molecules are known analogues of dopamine including a prodrug, while the other thirty-four molecules are currently being tested for their activity against all dopamine receptors. The results from both these test cases have proved that the HSB method provides a realistic solution to bridge the gap between the ever-increasing demand for new drugs to treat psychiatric disorders and the lack of efficient screening methods for GPCRs.
Development of a cervical cancer educational program for Chinese women using intervention mapping.
Hou, Su-I; Fernandez, Maria E; Parcel, Guy S
2004-01-01
This article describes the development of a program to increase Pap screening behavior among women in Taiwan. Intervention mapping, an innovative process of intervention design, guided the development of this program. The development process included a needs assessment identifying factors influencing Pap screening behavior relevant to Chinese women. The program used methods such as information transmission, modeling, persuasion, and facilitation. Strategies included direct mail communication, role-model stories and testimonials, and a telephone-counseling component. The delineation of specific plans for implementation and evaluation are also described.
Challenges and possible solutions to colorectal cancer screening for the underserved.
Gupta, Samir; Sussman, Daniel A; Doubeni, Chyke A; Anderson, Daniel S; Day, Lukejohn; Deshpande, Amar R; Elmunzer, B Joseph; Laiyemo, Adeyinka O; Mendez, Jeanette; Somsouk, Ma; Allison, James; Bhuket, Taft; Geng, Zhuo; Green, Beverly B; Itzkowitz, Steven H; Martinez, Maria Elena
2014-04-01
Colorectal cancer (CRC) is a leading cause of cancer mortality worldwide. CRC incidence and mortality can be reduced through screening. However, in the United States, screening participation remains suboptimal, particularly among underserved populations such as the uninsured, recent immigrants, and racial/ethnic minority groups. Increasing screening rates among underserved populations will reduce the US burden of CRC. In this commentary focusing on underserved populations, we highlight the public health impact of CRC screening, list key challenges to screening the underserved, and review promising approaches to boost screening rates. We identify four key policy and research priorities to increase screening among underserved populations: 1) actively promote the message, "the best test is the one that gets done"; 2) develop and implement methods to identify unscreened individuals within underserved population groups for screening interventions; 3) develop and implement approaches for organized screening delivery; and 4) fund and enhance programs and policies that provide access to screening, diagnostic follow-up, and CRC treatment for underserved populations. This commentary represents the consensus of a diverse group of experts in cancer control and prevention, epidemiology, gastroenterology, and primary care from across the country who formed the Coalition to Boost Screening among the Underserved in the United States. The group was organized and held its first annual working group meeting in conjunction with the World Endoscopy Organization's annual Colorectal Cancer Screening Committee meeting during Digestive Disease Week 2012 in San Diego, California.
Anthropometric methods for obesity screening in schoolchildren: the Ouro Preto Study.
Cándido, A P C; Alosta, J P S; Oliveira, C T; Freitas, R N; Freitas, S N; Machado-Coelho, G L L
2012-01-01
Childhood obesity is increasing dramatically in last decades. To evaluate the usefulness of body mass index (BMI), skinfold thickness (ST), waist circumference (WC), and foot-to-foot bioelectrical impedance (BIA-FF) for screening for obesity in mixed-race population, using the tetrapolar bioelectrical impedance (BIA-T) technique as reference method. A cross-sectional-based population study was performed in the city of Ouro Preto, Brazil, in 2006. Schoolchildren aged 6-15 years (n = 788) was randomly selected according to age and sex stratified by the proportion of students in each schools of the city. Nonparametric receiver operating characteristic (ROC) analysis was used to define the sensitivity and specificity for each method studied using the tetrapolar method as reference. The BMI and the BIA-FF were the most suitable for adiposity screening in pre-pubertal and pubertal stages because they present a better balance between sensitivity and specificity, and smaller misclassification. For post-pubertal boys, the BF-ST-D was the best body fat assessment method. The results suggest that BIA-FF and BMI are choice methods for obesity screening in mixed population and that the method choice for body fat screening must be done according to sexual maturity of boys and girls. The present study demonstrates the need to perform studies in wider mixed-race population to determine anthropometric parameters and to examine the predictive ability of methods and cut-offs here elucidated in the development of obesity.
Prioritizing chemicals for environmental management in China based on screening of potential risks
NASA Astrophysics Data System (ADS)
Yu, Xiangyi; Mao, Yan; Sun, Jinye; Shen, Yingwa
2014-03-01
The rapid development of China's chemical industry has created increasing pressure to improve the environmental management of chemicals. To bridge the large gap between the use and safe management of chemicals, we performed a comprehensive review of the international methods used to prioritize chemicals for environmental management. By comparing domestic and foreign methods, we confirmed the presence of this gap and identified potential solutions. Based on our literature review, we developed an appropriate screening method that accounts for the unique characteristics of chemical use within China. The proposed method is based on an evaluation using nine indices of the potential hazard posed by a chemical: three environmental hazard indices (persistence, bioaccumulation, and eco-toxicity), four health hazard indices (acute toxicity, carcinogenicity, mutagenicity, and reproductive and developmental toxicity), and two environmental exposure hazard indices (chemical amount and utilization pattern). The results of our screening agree with results of previous efforts from around the world, confirming the validity of the new system. The classification method will help decisionmakers to prioritize and identify the chemicals with the highest environmental risk, thereby providing a basis for improving chemical management in China.
Matsumoto, Hiroshi; Saito, Fumiyo; Takeyoshi, Masahiro
2015-12-01
Recently, the development of several gene expression-based prediction methods has been attempted in the fields of toxicology. CARCINOscreen® is a gene expression-based screening method to predict carcinogenicity of chemicals which target the liver with high accuracy. In this study, we investigated the applicability of the gene expression-based screening method to SD and Wistar rats by using CARCINOscreen®, originally developed with F344 rats, with two carcinogens, 2,4-diaminotoluen and thioacetamide, and two non-carcinogens, 2,6-diaminotoluen and sodium benzoate. After the 28-day repeated dose test was conducted with each chemical in SD and Wistar rats, microarray analysis was performed using total RNA extracted from each liver. Obtained gene expression data were applied to CARCINOscreen®. Predictive scores obtained by the CARCINOscreen® for known carcinogens were > 2 in all strains of rats, while non-carcinogens gave prediction scores below 0.5. These results suggested that the gene expression based screening method, CARCINOscreen®, can be applied to SD and Wistar rats, widely used strains in toxicological studies, by setting of an appropriate boundary line of prediction score to classify the chemicals into carcinogens and non-carcinogens.
A Quantum-Based Similarity Method in Virtual Screening.
Al-Dabbagh, Mohammed Mumtaz; Salim, Naomie; Himmat, Mubarak; Ahmed, Ali; Saeed, Faisal
2015-10-02
One of the most widely-used techniques for ligand-based virtual screening is similarity searching. This study adopted the concepts of quantum mechanics to present as state-of-the-art similarity method of molecules inspired from quantum theory. The representation of molecular compounds in mathematical quantum space plays a vital role in the development of quantum-based similarity approach. One of the key concepts of quantum theory is the use of complex numbers. Hence, this study proposed three various techniques to embed and to re-represent the molecular compounds to correspond with complex numbers format. The quantum-based similarity method that developed in this study depending on complex pure Hilbert space of molecules called Standard Quantum-Based (SQB). The recall of retrieved active molecules were at top 1% and top 5%, and significant test is used to evaluate our proposed methods. The MDL drug data report (MDDR), maximum unbiased validation (MUV) and Directory of Useful Decoys (DUD) data sets were used for experiments and were represented by 2D fingerprints. Simulated virtual screening experiment show that the effectiveness of SQB method was significantly increased due to the role of representational power of molecular compounds in complex numbers forms compared to Tanimoto benchmark similarity measure.
Molecular toolbox for the identification of unknown genetically modified organisms.
Ruttink, Tom; Demeyer, Rolinde; Van Gulck, Elke; Van Droogenbroeck, Bart; Querci, Maddalena; Taverniers, Isabel; De Loose, Marc
2010-03-01
Competent laboratories monitor genetically modified organisms (GMOs) and products derived thereof in the food and feed chain in the framework of labeling and traceability legislation. In addition, screening is performed to detect the unauthorized presence of GMOs including asynchronously authorized GMOs or GMOs that are not officially registered for commercialization (unknown GMOs). Currently, unauthorized or unknown events are detected by screening blind samples for commonly used transgenic elements, such as p35S or t-nos. If (1) positive detection of such screening elements shows the presence of transgenic material and (2) all known GMOs are tested by event-specific methods but are not detected, then the presence of an unknown GMO is inferred. However, such evidence is indirect because it is based on negative observations and inconclusive because the procedure does not identify the causative event per se. In addition, detection of unknown events is hampered in products that also contain known authorized events. Here, we outline alternative approaches for analytical detection and GMO identification and develop new methods to complement the existing routine screening procedure. We developed a fluorescent anchor-polymerase chain reaction (PCR) method for the identification of the sequences flanking the p35S and t-nos screening elements. Thus, anchor-PCR fingerprinting allows the detection of unique discriminative signals per event. In addition, we established a collection of in silico calculated fingerprints of known events to support interpretation of experimentally generated anchor-PCR GM fingerprints of blind samples. Here, we first describe the molecular characterization of a novel GMO, which expresses recombinant human intrinsic factor in Arabidopsis thaliana. Next, we purposefully treated the novel GMO as a blind sample to simulate how the new methods lead to the molecular identification of a novel unknown event without prior knowledge of its transgene sequence. The results demonstrate that the new methods complement routine screening procedures by providing direct conclusive evidence and may also be useful to resolve masking of unknown events by known events.
Ohata, Hiroshi; Oka, Masashi; Yanaoka, Kimihiko; Shimizu, Yasuhito; Mukoubayashi, Chizu; Mugitani, Kouichi; Iwane, Masataka; Nakamura, Hideya; Tamai, Hideyuki; Arii, Kenji; Nakata, Hiroya; Yoshimura, Noriko; Takeshita, Tetsuya; Miki, Kazumasa; Mohara, Osamu; Ichinose, Masao
2005-10-01
With the aim of developing more efficient gastric cancer screening programs for use in Japan, we studied a new screening program that combines serum pepsinogen (PG) testing and barium digital radiography (DR). A total of 17 647 middle-aged male subjects underwent workplace screening over a 7-year period using a combination of PG testing and DR. This program's effectiveness, as well as other characteristics of the program, was analyzed. Forty-nine cases of gastric cancer were detected (comprising 88% early cancer cases). The detection rate was 0.28%, and the positive predictive value was 0.85%. The PG test detected 63.3% of cases, DR detected 69.4% of cases, and both tests were positive in 32.7% of cancer cases. The two methods were almost equally effective, and were considerably more effective than conventional screening using photofluorography. Each screening method detected a distinct gastric cancer subgroup; the PG test efficiently detected asymptomatic small early cancer with intestinal type histology, while DR was efficient at detecting cancers with depressed or ulcerated morphology and diffuse type histology. The cost for the detection of a single cancer was much less than that for conventional screening. In fact, it is possible to further reduce the cost of detecting a single cancer to a cost comparable to that of surgically resecting a single gastric cancer. Thus, it is probable that a highly efficient gastric cancer screening system can be implemented by combining the two screening methods. Such a screening program would be beneficial in a population at high risk for gastric cancer.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Richard A. Corbett; Dave Severance
2005-02-01
Formicary corrosion is an insidious form of localized pitting corrosion. Notoya (1997b) wrote, ?In Japan, this type of corrosion is found in approximately 10% of cases of premature failure of copper tubes.? Attack characteristically features very small surface pits which are not visible to the un-aided eye, and random directional changes in the underlying copper metal. Attack is rapid. Failures have occurred before installation, shortly thereafter, or within several years later. Objectives of this Research Project Conduct an in depth literature search on the subject of formicary corrosion. Define the corrosion mechanism. Develop a test method that will reproduce formicarymore » corrosion. Develop a test method for screening candidate materials that could cause formicary corrosion.« less
Malchaire, J B
2004-08-01
The first section of the document describes a risk-prevention strategy, called SOBANE, in four levels: screening, observation, analysis and expertise. The aim is to make risk prevention faster, more cost effective, and more effective in coordinating the contributions of the workers themselves, their management, the internal and external occupational health (OH) practitioners and the experts. These four levels are: screening, where the risk factors are detected by the workers and their management, and obvious solutions are implemented; observation, where the remaining problems are studied in more detail, one by one, and the reasons and the solutions are discussed in detail; analysis, where, when necessary, an OH practitioner is called upon to carry out appropriate measurements to develop specific solutions; expertise, where, in very sophisticated and rare cases, the assistance of an expert is called upon to solve a particular problem. The method for the participatory screening of the risks (in French: Dépistage Participatif des Risques), Déparis, is proposed for the first level screening of the SOBANE strategy. The work situation is systematically reviewed and all the aspects conditioning the easiness, the effectiveness and the satisfaction at work are discussed, in search of practical prevention measures. The points to be studied more in detail at level 2, observation, are identified. The method is carried out during a meeting of key workers and technical staff. The method proves to be simple, sparing in time and means and playing a significant role in the development of a dynamic plan of risk management and of a culture of dialogue in the company.
Chen, Jun; Chen, Jianwei; Wang, Sijia; Zhou, Guangmin; Chen, Danqing; Zhang, Huawei; Wang, Hong
2018-04-02
A novel, green, rapid, and precise polar RP-HPLC method has been successfully developed and screened for ectoine high-yield strain in marine bacteria. Ectoine is a polar and extremely useful solute which allows microorganisms to survive in extreme environmental salinity. This paper describes a polar-HPLC method employed polar RP-C18 (5 μm, 250 × 4.6 mm) using pure water as the mobile phase and a column temperature of 30 °C, coupled with a flow rate at 1.0 mL/min and detected under a UV detector at wavelength of 210 nm. Our method validation demonstrates excellent linearity (R 2 = 0.9993), accuracy (100.55%), and a limit of detection LOQ and LOD of 0.372 and 0.123 μgmL -1 , respectively. These results clearly indicate that the developed polar RP-HPLC method for the separation and determination of ectoine is superior to earlier protocols.
Developing an undue influence screening tool for Adult Protective Services.
Quinn, Mary Joy; Nerenberg, Lisa; Navarro, Adria E; Wilber, Kathleen H
2017-03-01
The study purpose was to develop and pilot an undue influence screening tool for California's Adult Protective Services (APS) personnel based on the definition of undue influence enacted into California law January 1, 2014. Methods included four focus groups with APS providers (n = 33), piloting the preliminary tool by APS personnel (n = 15), and interviews with four elder abuse experts and two APS administrators. Social service literature-including existing undue influence models-was reviewed, as were existing screening and assessment tools. Using the information from these various sources, the California Undue Influence Screening Tool (CUIST) was developed. It can be applied to APS cases and potentially adapted for use by other professionals and for use in other states. Implementation of the tool into APS practice, policy, procedures, and training of personnel will depend on the initiative of APS management. Future work will need to address the reliability and validity of CUIST.
Microfluidics for cell-based high throughput screening platforms - A review.
Du, Guansheng; Fang, Qun; den Toonder, Jaap M J
2016-01-15
In the last decades, the basic techniques of microfluidics for the study of cells such as cell culture, cell separation, and cell lysis, have been well developed. Based on cell handling techniques, microfluidics has been widely applied in the field of PCR (Polymerase Chain Reaction), immunoassays, organ-on-chip, stem cell research, and analysis and identification of circulating tumor cells. As a major step in drug discovery, high-throughput screening allows rapid analysis of thousands of chemical, biochemical, genetic or pharmacological tests in parallel. In this review, we summarize the application of microfluidics in cell-based high throughput screening. The screening methods mentioned in this paper include approaches using the perfusion flow mode, the droplet mode, and the microarray mode. We also discuss the future development of microfluidic based high throughput screening platform for drug discovery. Copyright © 2015 Elsevier B.V. All rights reserved.
Finkelstein, Marsha; Llanos, Imelda; Scheiman, Mitchell; Wagener, Sharon Gowdy
2014-01-01
Vision impairment is common in the first year after traumatic brain injury (TBI), including among service members whose brain injuries occurred during deployment in Iraq and Afghanistan. Occupational therapy practitioners provide routine vision screening to inform treatment planning and referral to vision specialists, but existing methods are lacking because many tests were developed for children and do not screen for vision dysfunction typical of TBI. An expert panel was charged with specifying the composition of a vision screening protocol for servicemembers with TBI. A modified nominal group technique fostered discussion and objective determinations of consensus. After considering 29 vision tests, the panel recommended a nine-test vision screening that examines functional performance, self-reported problems, far–near acuity, reading, accommodation, convergence, eye alignment and binocular vision, saccades, pursuits, and visual fields. Research is needed to develop reliable, valid, and clinically feasible vision screening protocols to identify TBI-related vision disorders in adults. PMID:25005505
Hasan, J A; Huq, A; Nair, G B; Garg, S; Mukhopadhyay, A K; Loomis, L; Bernstein, D; Colwell, R R
1995-11-01
We report on the development and testing of two monoclonal antibody-based rapid immunodiagnostic test kits, BengalScreen, a coagglutination test, and Bengal DFA, a direct fluorescent-antibody test, for direct detection of Vibrio cholerae O139 synonym Bengal in clinical and environmental specimens. The BengalScreen test requires less than 5 min to complete and can be used in the field. Bengal DFA, being more sensitive than BengalScreen, requires only one reagent and less than 20 min for detection and enumeration of V. cholerae O139 synonym Bengal. In tests for specificity, all 40 strains of V. cholerae O139 reacted with both test kits, whereas 157 strains of heterologous species examined did not, yielding 100% specificity in this study. A field trial was conducted in with both BengalScreen and Bengal DFA, and the results were compared with those obtained by conventional culture methods. BengalScreen demonstrated a sensitivity of 95%, a specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 94%. Results obtained by Bengal DFA, on the other hand, were 100% sensitive and 100% specific and yielded 100% positive and negative predictive values compared with culture methods. In a second evaluation, 93 stool specimens from Mexico that were negative for V. cholerae O139 by culture were also tested with both the BengalScreen and Bengal DFA kits. None of the 93 specimens were positive for V. cholerae O139 by both tests. A concentration method was optimized for screening of environmental water samples for V. cholerae O139 synonym Bengal with rapid test kits. BengalScreen results were unequivocally positive when water samples contained at least 2.0 x 10(3) CFU/ml, whereas Bengal DFA demonstrated an unequivocally positive reaction when the water sample contained at least 1.5 x 10(2) CFU/ml. When Bengal DFA was compared with conventional culture methods for enumeration of V. cholerae O139 synonym Bengal organisms, no difference was observed.
Li, Miao; Wang, Sicen; He, Langchong
2015-01-01
Natural products (NPs) are important sources of lead compounds in modern drug discovery. To facilitate the screening of volatile active compounds in NPs, we have developed a new biochromatography method that uses rat vascular smooth muscle cells (VSMC), which are rich in L-type calcium channels (LCC), to prepare the stationary phase. This integrated method, which couples cell membrane chromatography (CMC) with gas chromatography-mass spectrometry (GC-MS) via microextraction by packed sorbent (MEPS) technology, has been termed VSMC/CMC-MEPS-GC-MS. Methodological validation confirmed its specificity, reliability and convenience. Screening results for Radix Angelicae Dahuricae and Fructus Cnidii obtained using VSMC/CMC-MEPS-GC-MS were consistent with those obtained using VSMC/CMC-offline-GC-MS. MEPS connection plays as simplified solid-phase extraction and replaces the uncontrollable evaporation operation in reported offline connections, so our new method is supposed to be more efficient and reliable than the offline ones, especially for compounds that are volatile, thermally unstable or difficult to purify. In application, senkyunolide A and ligustilide were preliminary identified as the volatile active components in Rhizoma Chuanxiong. We have thus confirmed the suitability of VSMC/CMC-MEPS-GC-MS for volatile active compounds screening in NP. Copyright © 2014 Elsevier B.V. All rights reserved.
Yin, Zheng; Zhou, Xiaobo; Bakal, Chris; Li, Fuhai; Sun, Youxian; Perrimon, Norbert; Wong, Stephen TC
2008-01-01
Background The recent emergence of high-throughput automated image acquisition technologies has forever changed how cell biologists collect and analyze data. Historically, the interpretation of cellular phenotypes in different experimental conditions has been dependent upon the expert opinions of well-trained biologists. Such qualitative analysis is particularly effective in detecting subtle, but important, deviations in phenotypes. However, while the rapid and continuing development of automated microscope-based technologies now facilitates the acquisition of trillions of cells in thousands of diverse experimental conditions, such as in the context of RNA interference (RNAi) or small-molecule screens, the massive size of these datasets precludes human analysis. Thus, the development of automated methods which aim to identify novel and biological relevant phenotypes online is one of the major challenges in high-throughput image-based screening. Ideally, phenotype discovery methods should be designed to utilize prior/existing information and tackle three challenging tasks, i.e. restoring pre-defined biological meaningful phenotypes, differentiating novel phenotypes from known ones and clarifying novel phenotypes from each other. Arbitrarily extracted information causes biased analysis, while combining the complete existing datasets with each new image is intractable in high-throughput screens. Results Here we present the design and implementation of a novel and robust online phenotype discovery method with broad applicability that can be used in diverse experimental contexts, especially high-throughput RNAi screens. This method features phenotype modelling and iterative cluster merging using improved gap statistics. A Gaussian Mixture Model (GMM) is employed to estimate the distribution of each existing phenotype, and then used as reference distribution in gap statistics. This method is broadly applicable to a number of different types of image-based datasets derived from a wide spectrum of experimental conditions and is suitable to adaptively process new images which are continuously added to existing datasets. Validations were carried out on different dataset, including published RNAi screening using Drosophila embryos [Additional files 1, 2], dataset for cell cycle phase identification using HeLa cells [Additional files 1, 3, 4] and synthetic dataset using polygons, our methods tackled three aforementioned tasks effectively with an accuracy range of 85%–90%. When our method is implemented in the context of a Drosophila genome-scale RNAi image-based screening of cultured cells aimed to identifying the contribution of individual genes towards the regulation of cell-shape, it efficiently discovers meaningful new phenotypes and provides novel biological insight. We also propose a two-step procedure to modify the novelty detection method based on one-class SVM, so that it can be used to online phenotype discovery. In different conditions, we compared the SVM based method with our method using various datasets and our methods consistently outperformed SVM based method in at least two of three tasks by 2% to 5%. These results demonstrate that our methods can be used to better identify novel phenotypes in image-based datasets from a wide range of conditions and organisms. Conclusion We demonstrate that our method can detect various novel phenotypes effectively in complex datasets. Experiment results also validate that our method performs consistently under different order of image input, variation of starting conditions including the number and composition of existing phenotypes, and dataset from different screens. In our findings, the proposed method is suitable for online phenotype discovery in diverse high-throughput image-based genetic and chemical screens. PMID:18534020
Guldmann-Christensen, Mariann; Hauge Kyneb, Majbritt; Voogd, Kirsten; Andersen, Christina; Epistolio, Samantha; Merlo, Elisabetta; Yding Wolff, Tine; Hamilton-Dutoit, Stephen; Lorenzen, Jan; Christensen, Ulf Bech
2017-01-01
Activating mutations in codon 12 and codon 13 of the KRAS (Kirsten rat sarcoma viral oncogene homolog) gene are implicated in the development of several human cancer types and influence their clinical evaluation, treatment and prognosis. Numerous different methods for KRAS genotyping are currently available displaying a wide range of sensitivities, time to answer and requirements for laboratory equipment and user skills. Here we present SensiScreen® KRAS exon 2 simplex and multiplex CE IVD assays, that use a novel real-time PCR-based method for KRAS mutation detection based on PentaBase’s proprietary DNA analogue technology and designed to work on standard real-time PCR instruments. By means of the included BaseBlocker™ technology, we show that SensiScreen® specifically amplifies the mutated alleles of interest with no or highly subdued amplification of the wild type allele. Furthermore, serial dilutions of mutant DNA in a wild type background demonstrate that all SensiScreen® assays display a limit of detection that falls within the range of 0.25–1%. Finally, in three different colorectal cancer patient populations, SensiScreen® assays confirmed the KRAS genotype previously determined by commonly used methods for KRAS mutation testing, and notably, in two of the populations, SensiScreen® identified additional mutant positive cases not detected by common methods. PMID:28636636
Rahbarnia, Leila; Farajnia, Safar; Babaei, Hossein; Majidi, Jafar; Veisi, Kamal; Tanomand, Asghar; Akbari, Bahman
2016-11-01
Phage display is a prominent screening technique for development of novel high affinity antibodies against almost any antigen. However, removing false positive clones in screening process remains a challenge. The aim of this study was to develop an efficient and rapid method for isolation of high affinity scFvs by removing NSBs without losing rare specific clones. Therefore, a novel two rounds strategy called invert biopanning was developed for isolating high affinity scFvs against EGFRvIII antigen from human scFv library. The efficiency of invert biopanning method (procedure III) was analyzed by comparing with results of conventional biopanning methods (procedures I and II). According to the results of polyclonal ELISA, the second round of procedure III displayed highest binding affinity against EGFRvIII peptide accompanied by lowest NSB comparing to other two procedures. Several positive clones were identified among output phages of procedure III by monoclonal phage ELISA which displayed high affinity to EGFRvIII antigen. In conclusion, results of our study indicate that invert biopanning is an efficient method for avoiding NSBs and conservation of rare specific clones during screening of a scFv phage library. Novel anti EGFRvIII scFv isolated could be a promising candidate for potential use in treatment of EGFRvIII expressing cancers. Copyright © 2016 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.
The view from the trenches: part 2-technical considerations for EPR screening.
Nicolalde, Roberto J; Gougelet, Robert M; Rea, Michael; Williams, Benjamin B; Dong, Ruhong; Kmiec, Maciej M; Lesniewski, Piotr N; Swartz, Harold M
2010-02-01
There is growing awareness of the need for methodologies that can be used retrospectively to provide the biodosimetry needed to carry out screening and triage immediately after an event in which large numbers of people have potentially received clinically significant doses of ionizing radiation. The general approach to developing such methodologies has been a technology centric one, often ignoring the system integrations considerations that are key to their effective use. In this study an integrative approach for the evaluation and development of a physical biodosimetry technology was applied based on in vivo electron paramagnetic resonance (EPR) dosimetry. The EPR measurements are based on physical changes in tissues whose magnitudes are not affected by the factors that can confound biologically-based assessments. In this study the use of a pilot simulation exercise to evaluate an experimental EPR system and gather stakeholders' feedback early on in the development process is described. The exercise involved: ten non-irradiated participants, representatives from a local fire department; Department of Homeland Security certified exercise evaluators, EPR experts, physicians; and a human factors engineer. Stakeholders were in agreement that the EPR technology in its current state of development could be deployed for the screening of mass casualties. Furthermore, stakeholders' recommendations will be prioritized and incorporated in future developments of the EPR technique. While the results of this exercise were aimed specifically at providing feedback for the development of EPR dosimetry for screening mass casualties, the methods and lessons learned are likely to be applicable to other biodosimetric methods.
Stabilization of glucose-oxidase in the graphene paste for screen-printed glucose biosensor
NASA Astrophysics Data System (ADS)
Pepłowski, Andrzej; Janczak, Daniel; Jakubowska, Małgorzata
2015-09-01
Various methods and materials for enzyme stabilization within screen-printed graphene sensor were analyzed. Main goal was to develop technology allowing immediate printing of the biosensors in single printing process. Factors being considered were: toxicity of the materials used, ability of the material to be screen-printed (squeezed through the printing mesh) and temperatures required in the fabrication process. Performance of the examined sensors was measured using chemical amperometry method, then appropriate analysis of the measurements was conducted. The analysis results were then compared with the medical requirements. Parameters calculated were: correlation coefficient between concentration of the analyte and the measured electrical current (0.986) and variation coefficient for the particular concentrations of the analyte used as the calibration points. Variation of the measured values was significant only in ranges close to 0, decreasing for the concentrations of clinical importance. These outcomes justify further development of the graphene-based biosensors fabricated through printing techniques.
Computational diagnosis of canine lymphoma
NASA Astrophysics Data System (ADS)
Mirkes, E. M.; Alexandrakis, I.; Slater, K.; Tuli, R.; Gorban, A. N.
2014-03-01
One out of four dogs will develop cancer in their lifetime and 20% of those will be lymphoma cases. PetScreen developed a lymphoma blood test using serum samples collected from several veterinary practices. The samples were fractionated and analysed by mass spectrometry. Two protein peaks, with the highest diagnostic power, were selected and further identified as acute phase proteins, C-Reactive Protein and Haptoglobin. Data mining methods were then applied to the collected data for the development of an online computer-assisted veterinary diagnostic tool. The generated software can be used as a diagnostic, monitoring and screening tool. Initially, the diagnosis of lymphoma was formulated as a classification problem and then later refined as a lymphoma risk estimation. Three methods, decision trees, kNN and probability density evaluation, were used for classification and risk estimation and several preprocessing approaches were implemented to create the diagnostic system. For the differential diagnosis the best solution gave a sensitivity and specificity of 83.5% and 77%, respectively (using three input features, CRP, Haptoglobin and standard clinical symptom). For the screening task, the decision tree method provided the best result, with sensitivity and specificity of 81.4% and >99%, respectively (using the same input features). Furthermore, the development and application of new techniques for the generation of risk maps allowed their user-friendly visualization.
Rebentisch, D P; Rebentisch, H D; Thomas, K; Karat, S; Jadhav, A J
1995-12-01
Carcinoma of the breast is the third most common cancer in Indian women. With rapid industrialization and effective control of communicable diseases, better diagnostic and treatment facilities, cancer is emerging as a major health problem. Since early detection is the only way to reduce morbidity and mortality from breast cancer, we undertook a pilot project to evaluate efficacy of using existing manpower and resources for screening women in the high risk group. Methodology pros and cons, results, and recommendations are presented. Our method can be adopted by any developing country interested in a screening programme for malignant disease.
NASA Technical Reports Server (NTRS)
Tegart, J. R.; Aydelott, J. C.
1978-01-01
The design of surface tension propellant acquisition systems using fine-mesh screen must take into account all factors that influence the liquid pressure differentials within the system. One of those factors is spacecraft vibration. Analytical models to predict the effects of vibration have been developed. A test program to verify the analytical models and to allow a comparative evaluation of the parameters influencing the response to vibration was performed. Screen specimens were tested under conditions simulating the operation of an acquisition system, considering the effects of such parameters as screen orientation and configuration, screen support method, screen mesh, liquid flow and liquid properties. An analytical model, based on empirical coefficients, was most successful in predicting the effects of vibration.
Microplate Bioassay for Determining Substrate Selectivity of "Candida rugosa" Lipase
ERIC Educational Resources Information Center
Wang, Shi-zhen; Fang, Bai-shan
2012-01-01
Substrate selectivity of "Candida rugosa" lipase was tested using "p"-nitrophenyl esters of increasing chain length (C[subscript 1], C[subscript 7], C[subscript 15]) using the high-throughput screening method. A fast and easy 96-well microplate bioassay was developed to help students learn and practice biotechnological specificity screen. The…
Code of Federal Regulations, 2010 CFR
2010-04-01
... POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Methods and Standards for Lead-Paint Hazard... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Lead-based paint inspections, paint testing, risk assessments, lead-hazard screens, and reevaluations. 35.1320 Section 35.1320 Housing and...
Code of Federal Regulations, 2014 CFR
2014-04-01
... POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Methods and Standards for Lead-Paint Hazard... 24 Housing and Urban Development 1 2014-04-01 2014-04-01 false Lead-based paint inspections, paint testing, risk assessments, lead-hazard screens, and reevaluations. 35.1320 Section 35.1320 Housing and...
Code of Federal Regulations, 2013 CFR
2013-04-01
... POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Methods and Standards for Lead-Paint Hazard... 24 Housing and Urban Development 1 2013-04-01 2013-04-01 false Lead-based paint inspections, paint testing, risk assessments, lead-hazard screens, and reevaluations. 35.1320 Section 35.1320 Housing and...
Code of Federal Regulations, 2012 CFR
2012-04-01
... POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Methods and Standards for Lead-Paint Hazard... 24 Housing and Urban Development 1 2012-04-01 2012-04-01 false Lead-based paint inspections, paint testing, risk assessments, lead-hazard screens, and reevaluations. 35.1320 Section 35.1320 Housing and...
Code of Federal Regulations, 2011 CFR
2011-04-01
... POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Methods and Standards for Lead-Paint Hazard... 24 Housing and Urban Development 1 2011-04-01 2011-04-01 false Lead-based paint inspections, paint testing, risk assessments, lead-hazard screens, and reevaluations. 35.1320 Section 35.1320 Housing and...
An experience of qualified preventive screening: shiraz smart screening software.
Islami Parkoohi, Parisa; Zare, Hashem; Abdollahifard, Gholamreza
2015-01-01
Computerized preventive screening software is a cost effective intervention tool to address non-communicable chronic diseases. Shiraz Smart Screening Software (SSSS) was developed as an innovative tool for qualified screening. It allows simultaneous smart screening of several high-burden chronic diseases and supports reminder notification functionality. The extent in which SSSS affects screening quality is also described. Following software development, preventive screening and annual health examinations of 261 school staff (Medical School of Shiraz, Iran) was carried out in a software-assisted manner. To evaluate the quality of the software-assisted screening, we used quasi-experimental study design and determined coverage, irregular attendance and inappropriateness proportions in relation with the manual and software-assisted screening as well as the corresponding number of requested tests. In manual screening method, 27% of employees were covered (with 94% irregular attendance) while by software-assisted screening, the coverage proportion was 79% (attendance status will clear after the specified time). The frequency of inappropriate screening test requests, before the software implementation, was 41.37% for fasting plasma glucose, 41.37% for lipid profile, 0.84% for occult blood, 0.19% for flexible sigmoidoscopy/colonoscopy, 35.29% for Pap smear, 19.20% for mammography and 11.2% for prostate specific antigen. All of the above were corrected by the software application. In total, 366 manual screening and 334 software-assisted screening tests were requested. SSSS is an innovative tool to improve the quality of preventive screening plans in terms of increased screening coverage, reduction in inappropriateness and the total number of requested tests.
SELEX-Based Screening of Exosome-Tropic RNA.
Yamashita, Takuma; Shinotsuka, Haruka; Takahashi, Yuki; Kato, Kana; Nishikawa, Makiya; Takakura, Yoshinobu
2017-01-01
Cell-derived nanosized vesicles or exosomes are expected to become delivery carriers for functional RNAs, such as small interfering RNA (siRNA). A method to efficiently load functional RNAs into exosomes is required for the development of exosome-based delivery carriers of functional RNAs. However, there is no method to find exosome-tropic exogenous RNA sequences. In this study, we used a systematic evolution of ligands by exponential enrichment (SELEX) method to screen exosome-tropic RNAs that can be used to load functional RNAs into exosomes by conjugation. Pooled single stranded 80-base RNAs, each of which contains a randomized 40-base sequence, were transfected into B16-BL6 murine melanoma cells and exosomes were collected from the cells. RNAs extracted from the exosomes were subjected to next round of SELEX. Cloning and sequencing of RNAs in SELEX-screened RNA pools showed that 29 of 56 clones had a typical RNA sequence. The sequence found by SELEX was enriched in exosomes after transfection to B16-BL6 cells. The results show that the SELEX-based method can be used for screening of exosome-tropic RNAs.
Bernalte, E; Marín Sánchez, C; Pinilla Gil, E
2011-03-09
The applicability of commercial screen-printed gold electrodes (SPGEs) for the determination of Hg(II) in ambient water samples by square wave anodic stripping voltammetry has been demonstrated. Electrode conditioning procedures, chemical and instrumental variables have been optimized to develop a reliable method capable of measuring dissolved mercury in the low ng mL(-1) range (detection limit 1.1 ng mL(-1)), useful for pollution monitoring or screening purposes. The proposed method was tested with the NIST 1641d Mercury in Water Standard Reference Material (recoveries 90.0-110%) and the NCS ZC 76303 Mercury in Water Certified Reference Material (recoveries 82.5-90.6%). Waste water samples from industrial origin and fortified rain water samples were assayed for mercury by the proposed method and by a reference ICP-MS method, with good agreement. Screen printing technology thus opens a useful way for the construction of reliable electrochemical sensors for decentralized or even field Hg(II) testing. Copyright © 2011 Elsevier B.V. All rights reserved.
CORALINA: a universal method for the generation of gRNA libraries for CRISPR-based screening.
Köferle, Anna; Worf, Karolina; Breunig, Christopher; Baumann, Valentin; Herrero, Javier; Wiesbeck, Maximilian; Hutter, Lukas H; Götz, Magdalena; Fuchs, Christiane; Beck, Stephan; Stricker, Stefan H
2016-11-14
The bacterial CRISPR system is fast becoming the most popular genetic and epigenetic engineering tool due to its universal applicability and adaptability. The desire to deploy CRISPR-based methods in a large variety of species and contexts has created an urgent need for the development of easy, time- and cost-effective methods enabling large-scale screening approaches. Here we describe CORALINA (comprehensive gRNA library generation through controlled nuclease activity), a method for the generation of comprehensive gRNA libraries for CRISPR-based screens. CORALINA gRNA libraries can be derived from any source of DNA without the need of complex oligonucleotide synthesis. We show the utility of CORALINA for human and mouse genomic DNA, its reproducibility in covering the most relevant genomic features including regulatory, coding and non-coding sequences and confirm the functionality of CORALINA generated gRNAs. The simplicity and cost-effectiveness make CORALINA suitable for any experimental system. The unprecedented sequence complexities obtainable with CORALINA libraries are a necessary pre-requisite for less biased large scale genomic and epigenomic screens.
Vogel, Simon M; Bauer, Matthias R; Boeckler, Frank M
2011-10-24
For widely applied in silico screening techniques success depends on the rational selection of an appropriate method. We herein present a fast, versatile, and robust method to construct demanding evaluation kits for objective in silico screening (DEKOIS). This automated process enables creating tailor-made decoy sets for any given sets of bioactives. It facilitates a target-dependent validation of docking algorithms and scoring functions helping to save time and resources. We have developed metrics for assessing and improving decoy set quality and employ them to investigate how decoy embedding affects docking. We demonstrate that screening performance is target-dependent and can be impaired by latent actives in the decoy set (LADS) or enhanced by poor decoy embedding. The presented method allows extending and complementing the collection of publicly available high quality decoy sets toward new target space. All present and future DEKOIS data sets will be made accessible at www.dekois.com.
Truong, Hai An; Jeong, Chan Young; Lee, Won Je; Lee, Byung Cheon; Chung, Namhyun; Kang, Chon-Sik; Cheong, Young-Keun; Hong, Suk-Whan; Lee, Hojoung
2017-07-19
Thermotolerance in plants is a topic of concern given the current trends in global warming. Here, we aimed to develop a rapid and reproducible screening method for selection of heat stress-tolerant wheat varieties to expedite the breeding process. We tested the robustness of the screen in three Korean wheat cultivars, "BackJung", "KeumKang", and "ChoKyeong". We showed that 4-day-old seedlings of "KeumKang" had the highest survival rates after a 45 °C treatment for 20 h. Moreover, the ability to retain chlorophyll and antioxidant activity was also highest in "KeumKang". The increase in malondialdehyde content in "ChoKyeong" indicated that this cultivar showed the greatest damage after heat stress. Collectively, our results showed that "KeumKang" is the most heat-tolerant cultivar of the three examined. In conclusion, the most reliable and rapid screening method in our investigation was survival rate examined at lethal temperature.
Vidal-Melgosa, Silvia; Pedersen, Henriette L.; Schückel, Julia; Arnal, Grégory; Dumon, Claire; Amby, Daniel B.; Monrad, Rune Nygaard; Westereng, Bjørge; Willats, William G. T.
2015-01-01
Carbohydrate-active enzymes have multiple biological roles and industrial applications. Advances in genome and transcriptome sequencing together with associated bioinformatics tools have identified vast numbers of putative carbohydrate-degrading and -modifying enzymes including glycoside hydrolases and lytic polysaccharide monooxygenases. However, there is a paucity of methods for rapidly screening the activities of these enzymes. By combining the multiplexing capacity of carbohydrate microarrays with the specificity of molecular probes, we have developed a sensitive, high throughput, and versatile semiquantitative enzyme screening technique that requires low amounts of enzyme and substrate. The method can be used to assess the activities of single enzymes, enzyme mixtures, and crude culture broths against single substrates, substrate mixtures, and biomass samples. Moreover, we show that the technique can be used to analyze both endo-acting and exo-acting glycoside hydrolases, polysaccharide lyases, carbohydrate esterases, and lytic polysaccharide monooxygenases. We demonstrate the potential of the technique by identifying the substrate specificities of purified uncharacterized enzymes and by screening enzyme activities from fungal culture broths. PMID:25657012
NASA Astrophysics Data System (ADS)
Suzuki, H.; Mizuguchi, R.; Matsuhiro, M.; Kawata, Y.; Niki, N.; Nakano, Y.; Ohmatsu, H.; Kusumoto, M.; Tsuchida, T.; Eguchi, K.; Kaneko, M.; Moriyama, N.
2015-03-01
Computed tomography has been used for assessing structural abnormalities associated with emphysema. It is important to develop a robust CT based imaging biomarker that would allow quantification of emphysema progression in early stage. This paper presents effect of smoking on emphysema progression using annual changes of low attenuation volume (LAV) by each lung lobe acquired from low-dose CT images in longitudinal screening for lung cancer. The percentage of LAV (LAV%) was measured after applying CT value threshold method and small noise reduction. Progression of emphysema was assessed by statistical analysis of the annual changes represented by linear regression of LAV%. This method was applied to 215 participants in lung cancer CT screening for five years (18 nonsmokers, 85 past smokers, and 112 current smokers). The results showed that LAV% is useful to classify current smokers with rapid progression of emphysema (0.2%/year, p<0.05). This paper demonstrates effectiveness of the proposed method in diagnosis and prognosis of early emphysema in CT screening for lung cancer.
Ren, Fuzheng; Sun, Hanjing; Cui, Lin; Si, Yike; Chen, Ning; Ren, Guobin; Jing, Qiufang
2018-06-01
Drugs in amorphous solid dispersions (ASDs) are highly dispersed in hydrophilic polymeric carriers, which also help to restrain recrystallization and stabilize the ASDs. In this study, microscopic observation after antisolvent recrystallization was developed as a rapid screening method to select appropriate polymers for the initial design filgotinib (FTN) ASDs. Using solvent evaporation, FTN ASDs with the polymers were prepared, and accelerated experimentation validated this screening method. Fourier-transform infrared spectroscopy, Raman scattering, and nuclear magnetic resonance revealed hydrogen-bonding formation in the drug-polymer binary system, which was critical for ASDs stabilization. A Flory-Huggins interaction parameter and water sorption isotherms were applied to evaluate the strength of the interaction between FTN and the polymers. The dissolution rate was also significantly improved by ASDs formulation, and the presence of the polymers exerted solubilization effects. These results suggested the efficacy of this screening method as a preliminary tool for polymer selection in ASDs design. Copyright © 2018 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.
In order to screen large numbers of chemicals for their potential to produce developmental neurotoxicity new, in vitro methods are needed. One approach is to develop methods based on the biologic processes which underlie brain development including the growth and maturation of ce...
Parental views on informed consent for expanded newborn screening.
Moody, Louise; Choudhry, Kubra
2013-09-01
An increasing array of rare inherited conditions can be detected as part of the universal newborn screening programme. The introduction and evaluation of these service developments require consideration of the ethical issues involved and appropriate mechanisms for informing parents and gaining consent if required. Exploration of parental views is needed to inform the debate and specifically consider whether more flexible protocols are needed to fit with the public perception of new developments in this context. This study has been undertaken to explore perceptions and attitudes of parents and future parents to an expanded newborn screening programme in the United Kingdom and the necessary information provision and consent processes. A mixed methods study involving focus groups (n = 29) and a web-survey (n = 142) undertaken with parents and future parents. Parents want guaranteed information provision with clear decision-making powers and an awareness of the choices available to them. The difference between existing screening provision and expanded screening was not considered to be significant enough by participants to warrant formal written, informed consent for expanded screening. It is argued that the ethical review processes need to be more flexible towards the provision of information and consent processes for service developments in newborn screening. © 2011 John Wiley & Sons Ltd.
Albu, Silvia A; Al-Karmi, Salma A; Vito, Alyssa; Dzandzi, James P K; Zlitni, Aimen; Beckford-Vera, Denis; Blacker, Megan; Janzen, Nancy; Patel, Ramesh M; Capretta, Alfredo; Valliant, John F
2016-01-20
A convenient method to prepare radioiodinated tetrazines was developed, such that a bioorthogonal inverse electron demand Diels-Alder reaction can be used to label biomolecules with iodine-125 for in vitro screening and in vivo biodistribution studies. The tetrazine was prepared by employing a high-yielding oxidative halo destannylation reaction that concomitantly oxidized the dihydrotetrazine precursor. The product reacts quickly and efficiently with trans-cyclooctene derivatives. Utility was demonstrated through antibody and hormone labeling experiments and by evaluating products using standard analytical methods, in vitro assays, and quantitative biodistribution studies where the latter was performed in direct comparison to Bolton-Hunter and direct iodination methods. The approach described provides a convenient and advantageous alternative to conventional protein iodination methods that can expedite preclinical development and evaluation of biotherapeutics.
Amarasinghe, Kande; Chu, Pak-Sin; Evans, Eric; Reimschuessel, Renate; Hasbrouck, Nicholas; Jayasuriya, Hiranthi
2012-05-23
This paper describes the development of a fast method to screen and confirm methyltestosterone 17-O-glucuronide (MT-glu) in tilapia bile. The method consists of solid-phase extraction (SPE) followed by high-performance liquid chromatography-mass spectrometry. The system used was an Agilent 6530 Q-TOF with an Agilent Jet stream electrospray ionization interface. The glucuronide detected in the bile was characterized as MT-glu by comparison with a chemically synthesized standard. MT-glu was detected in bile for up to 7 days after dosing. Semiquantification was done with matrix-matched calibration curves, because MT-glu showed signal suppression due to matrix effects. This method provides a suitable tool to monitor the illegal use of methyltestosterone in tilapia culture.
Concise review: modeling central nervous system diseases using induced pluripotent stem cells.
Zeng, Xianmin; Hunsberger, Joshua G; Simeonov, Anton; Malik, Nasir; Pei, Ying; Rao, Mahendra
2014-12-01
Induced pluripotent stem cells (iPSCs) offer an opportunity to delve into the mechanisms underlying development while also affording the potential to take advantage of a number of naturally occurring mutations that contribute to either disease susceptibility or resistance. Just as with any new field, several models of screening are being explored, and innovators are working on the most efficient methods to overcome the inherent limitations of primary cell screens using iPSCs. In the present review, we provide a background regarding why iPSCs represent a paradigm shift for central nervous system (CNS) disease modeling. We describe the efforts in the field to develop more biologically relevant CNS disease models, which should provide screening assays useful for the pharmaceutical industry. We also provide some examples of successful uses for iPSC-based screens and suggest that additional development could revolutionize the field of drug discovery. The development and implementation of these advanced iPSC-based screens will create a more efficient disease-specific process underpinned by the biological mechanism in a patient- and disease-specific manner rather than by trial-and-error. Moreover, with careful and strategic planning, shared resources can be developed that will enable exponential advances in the field. This will undoubtedly lead to more sensitive and accurate screens for early diagnosis and allow the identification of patient-specific therapies, thus, paving the way to personalized medicine. ©AlphaMed Press.
Recent developments and new applications of tandem mass spectrometry in newborn screening.
Rinaldo, Piero; Tortorelli, Silvia; Matern, Dietrich
2004-08-01
To summarize recent developments in the field of newborn screening related to the use of tandem mass spectrometry as an analytic platform. Novel inborn errors of metabolism with informative amino acid and/or acylcarnitine profiles have been characterized, increasing the complexity of the differential diagnosis of abnormal results. In addition, methods have been developed for the analysis in dried blood spots of steroids and lysosomal enzymes. Previously unrecognized genotype/phenotype correlations have been found among cohorts of patients whose conditions were diagnosed by screening rather than clinically. Several government entities and professional organizations have issued position statements on newborn screening, and worldwide outcome studies continue to underscore the clinical and financial benefits of expanded newborn screening. Although it is done inconsistently, newborn screening in the United States is undergoing a rapid expansion driven by the introduction of tandem mass spectrometry in at least 34 state programs. This technology is also used to detect disease markers beyond acylcarnitines and amino acids, as both primary and second-tier tests. In addition to analytic improvements, there is a trend toward the development of joint programs not limited to contiguous geographic areas, often based upon public-private partnerships. This review will summarize several new developments in the field that have occurred since early 2003 and will mention others likely to occur in the near future.
Screening of Osteogenic-Enhancing Short Peptides from BMPs for Biomimetic Material Applications
Kanie, Kei; Kurimoto, Rio; Tian, Jing; Ebisawa, Katsumi; Narita, Yuji; Honda, Hiroyuki; Kato, Ryuji
2016-01-01
Bone regeneration is an important issue in many situations, such as bone fracture and surgery. Umbilical cord mesenchymal stem cells (UC-MSCs) are promising cell sources for bone regeneration. Bone morphogenetic proteins and their bioactive peptides are biomolecules known to enhance the osteogenic differentiation of MSCs. However, fibrosis can arise during the development of implantable biomaterials. Therefore, it is important to control cell organization by enhancing osteogenic proliferation and differentiation and inhibiting fibroblast proliferation. Thus, we focused on the screening of such osteogenic-enhancing peptides. In the present study, we developed new peptide array screening platforms to evaluate cell proliferation and alkaline phosphatase activity in osteoblasts, UC-MSCs and fibroblasts. The conditions for the screening platform were first defined using UC-MSCs and an osteogenic differentiation peptide known as W9. Next, in silico screening to define the candidate peptides was carried out to evaluate the homology of 19 bone morphogenetic proteins. Twenty-five candidate 9-mer peptides were selected for screening. Finally, the screening of osteogenic-enhancing (osteogenic cell-selective proliferation and osteogenic differentiation) short peptide was carried out using the peptide array method, and three osteogenic-enhancing peptides were identified, confirming the validity of this screening. PMID:28773850
Rapid polymerase chain reaction screening of Helicobacter pylori chromosomal point mutations.
Ge, Z; Taylor, D E
1997-09-01
Microdiversity (within individual genes) in the genomes of different Helicobacter pylori strains has been demonstrated to be more frequent than that seen in other prokaryotes. Point mutations in some genes, such as the vacA and 23S ribosomal RNA genes could result in the alteration of pathogenicity or antibiotic susceptibility of individual H. pylori strains. Development of a simple, rapid, and reliable screening method would be useful in the molecular characterization of genetic variation among different H. pylori strains. The copP gene from H. pylori UA802 was used as a model for developing a mutation screening method. Four point mutations were introduced into the copP gene by in vitro site-directed mutagenesis and were verified by DNA sequencing. The mutated copP gene replaced the wild-type locus by natural transformation and homologous recombination. The site-specific mutants were screened by polymerase chain reaction (PCR) using 3'-end mismatched primers. The origins of the PCR fragments were demonstrated by Southern hybridization with the copP-derived DNA probe. Three of these four mutations were characterized by PCR with the specific primers that contained the 3'-terminal nucleotide complementary only to the mutated nucleotide on both plasmid and chromosomal DNA templates. One mutation was able to be identified with the foregoing primer containing an additional wild-type nucleotide at its 3'-end. Point mutant screening with these specific primers offers 100% sensitivity in the aforementioned conditions. To achieve optimal screening, the concentration of magnesium and the annealing temperature have to be adjusted. The procedure reported in this study is a simple, economical, rapid, and efficient approach in the identification of site-specific mutations on both plasmids and chromosomal DNA. Although the method was developed by using a specified H. pylori gene, it can be extended easily to other genes of interest in H. pylori or other organisms.
A screening tool for delineating subregions of steady recharge within groundwater models
Dickinson, Jesse; Ferré, T.P.A.; Bakker, Mark; Crompton, Becky
2014-01-01
We have developed a screening method for simplifying groundwater models by delineating areas within the domain that can be represented using steady-state groundwater recharge. The screening method is based on an analytical solution for the damping of sinusoidal infiltration variations in homogeneous soils in the vadose zone. The damping depth is defined as the depth at which the flux variation damps to 5% of the variation at the land surface. Groundwater recharge may be considered steady where the damping depth is above the depth of the water table. The analytical solution approximates the vadose zone diffusivity as constant, and we evaluated when this approximation is reasonable. We evaluated the analytical solution through comparison of the damping depth computed by the analytic solution with the damping depth simulated by a numerical model that allows variable diffusivity. This comparison showed that the screening method conservatively identifies areas of steady recharge and is more accurate when water content and diffusivity are nearly constant. Nomograms of the damping factor (the ratio of the flux amplitude at any depth to the amplitude at the land surface) and the damping depth were constructed for clay and sand for periodic variations between 1 and 365 d and flux means and amplitudes from nearly 0 to 1 × 10−3 m d−1. We applied the screening tool to Central Valley, California, to identify areas of steady recharge. A MATLAB script was developed to compute the damping factor for any soil and any sinusoidal flux variation.
De Spiegelaere, Ward; Philippé, Jan; Vervisch, Karen; Verhofstede, Chris; Malatinkova, Eva; Kiselinova, Maja; Trypsteen, Wim; Bonczkowski, Pawel; Vogelaers, Dirk; Callens, Steven; Ruelle, Jean; Kabeya, Kabamba; De Wit, Stephane; Van Acker, Petra; Van Sandt, Vicky; Emonds, Marie-Paule; Coucke, Paul; Sermijn, Erica; Vandekerckhove, Linos
2015-01-01
Abacavir is a nucleoside reverse transcriptase inhibitor used as part of combination antiretroviral therapy in HIV-1-infected patients. Because this drug can cause a hypersensitivity reaction that is correlated with the presence of the HLA-B*57:01 allotype, screening for the presence of HLA-B*57:01 is recommended before abacavir initiation. Different genetic assays have been developed for HLA-B*57:01 screening, each with specific sensitivity, turnaround time and assay costs. Here, a new real-time PCR (qPCR) based analysis is described and compared to sequence specific primer PCR with capillary electrophoresis (SSP PCR CE) on 149 patient-derived samples, using sequence specific oligonucleotide hybridization combined with high resolution SSP PCR as gold standard. In addition to these PCR based methods, a complementary approach was developed using flow cytometry with an HLA-B17 specific monoclonal antibody as a pre-screening assay to diminish the number of samples for genetic testing. All three assays had a maximum sensitivity of >99. However, differences in specificity were recorded, i.e. 84.3%, 97.2% and >99% for flow cytometry, qPCR and SSP PCR CE respectively. Our data indicate that the most specific and sensitive of the compared methods is the SSP PCR CE. Flow cytometry pre-screening can substantially decrease the number of genetic tests for HLA-B*57:01 typing in a clinical setting.
Knepper, Caleb; Mou, Beiquan
2015-01-01
This protocol describes a method by which a large collection of the leafy green vegetable lettuce (Lactuca sativa L.) germplasm was screened for likely drought-tolerance traits. Fresh water availability for agricultural use is a growing concern across the United States as well as many regions of the world. Short-term drought events along with regulatory intervention in the regulation of water availability coupled with the looming threat of long-term climate shifts that may lead to reduced precipitation in many important agricultural regions has increased the need to hasten the development of crops adapted for improved water use efficiency in order to maintain or expand production in the coming years. This protocol is not meant as a step-by-step guide to identifying at either the physiological or molecular level drought-tolerance traits in lettuce, but rather is a method developed and refined through the screening of thousands of different lettuce varieties. The nature of this screen is based in part on the streamlined measurements focusing on only three water-stress indicators: leaf relative water content, wilt, and differential plant growth following drought-stress. The purpose of rapidly screening a large germplasm collection is to narrow the candidate pool to a point in which more intensive physiological, molecular, and genetic methods can be applied to identify specific drought-tolerant traits in either the lab or field. Candidates can also be directly incorporated into breeding programs as a source of drought-tolerance traits. PMID:25938876
Knepper, Caleb; Mou, Beiquan
2015-04-17
This protocol describes a method by which a large collection of the leafy green vegetable lettuce (Lactuca sativa L.) germplasm was screened for likely drought-tolerance traits. Fresh water availability for agricultural use is a growing concern across the United States as well as many regions of the world. Short-term drought events along with regulatory intervention in the regulation of water availability coupled with the looming threat of long-term climate shifts that may lead to reduced precipitation in many important agricultural regions has increased the need to hasten the development of crops adapted for improved water use efficiency in order to maintain or expand production in the coming years. This protocol is not meant as a step-by-step guide to identifying at either the physiological or molecular level drought-tolerance traits in lettuce, but rather is a method developed and refined through the screening of thousands of different lettuce varieties. The nature of this screen is based in part on the streamlined measurements focusing on only three water-stress indicators: leaf relative water content, wilt, and differential plant growth following drought-stress. The purpose of rapidly screening a large germplasm collection is to narrow the candidate pool to a point in which more intensive physiological, molecular, and genetic methods can be applied to identify specific drought-tolerant traits in either the lab or field. Candidates can also be directly incorporated into breeding programs as a source of drought-tolerance traits.
Yuan, Jinbin; Chen, Yang; Liang, Jian; Wang, Chong-Zhi; Liu, Xiaofei; Yan, Zhihong; Tang, Yi; Li, Jiankang; Yuan, Chun-Su
2016-12-01
Ginseng is one of the most widely used natural medicines in the world. Recent studies have suggested Panax ginseng has a wide range of beneficial effects on aging, central nervous system disorders, and neurodegenerative diseases. However, knowledge about the specific bioactive components of ginseng is still limited. This work aimed to screen for the bioactive components in Panax ginseng that act against neurodegenerative diseases, using the target cell-based bioactivity screening method. Firstly, component analysis of Panax ginseng extracts was performed by UPLC-QTOF-MS, and a total of 54 compounds in white ginseng were characterized and identified according to the retention behaviors, accurate MW, MS characteristics, parent nucleus, aglycones, side chains, and literature data. Then target cell-based bioactivity screening method was developed to predict the candidate compounds in ginseng with SH-SY5Y cells. Four ginsenosides, Rg 2 , Rh 1 , Ro, and Rd, were observed to be active. The target cell-based bioactivity screening method coupled with UPLC-QTOF-MS technique has suitable sensitivity and it can be used as a screening tool for low content bioactive constituents in natural products. Copyright © 2016 Elsevier B.V. All rights reserved.
Convenient, Sensitive and High-Throughput Method for Screening Botanic Origin
NASA Astrophysics Data System (ADS)
Yuan, Yuan; Jiang, Chao; Liu, Libing; Yu, Shulin; Cui, Zhanhu; Chen, Min; Lin, Shufang; Wang, Shu; Huang, Luqi
2014-06-01
In this work, a rapid (within 4-5 h), sensitive and visible new method for assessing botanic origin is developed by combining loop-mediated isothermal amplification with cationic conjugated polymers. The two Chinese medicinal materials (Jin-Yin-Hua and Shan-Yin-Hua) with similar morphology and chemical composition were clearly distinguished by gene SNP genotyping assays. The identification of plant species in Patented Chinese drugs containing Lonicera buds is successfully performed using this detection system. The method is also robust enough to be used in high-throughput screening. This new method is very helpful to identify herbal materials, and is beneficial for detecting safety and quality of botanic products.
REVIEW OF RAPID METHODS FOR ASSESSING WETLAND CONDITION
We evaluated over 40 wetland rapid assessment methods developed for a variety of purposes for their use in the assessment of ecological integrity or ecosystem condition. Four criteria were used to screen methods: 1) the method can be used to measure condition, 2) it is truly rap...
Nie, Honggang; Li, Xianjiang; Hua, Zhendong; Pan, Wei; Bai, Yanping; Fu, Xiaofang
2016-08-01
With the amounts and types of new psychoactive substances (NPSs) increasing rapidly in recent years, an excellent high-throughput method for the analysis of these compounds is urgently needed. In this article, a rapid screening method and a quantitative analysis method for 11 NPSs are described and compared, respectively. A simple direct analysis in real time mass spectrometry (DART-MS) method was developed for the analysis of 11 NPSs including three categories of these substances present on the global market such as four cathinones, one phenylethylamine, and six synthetic cannabinoids. In order to analyze these compounds quantitatively with better accuracy and sensitivity, another rapid analytical method with a low limit of detection (LOD) was also developed using liquid chromatography/electrospray ionization quadrupole time-of-flight mass spectrometry (LC/QTOFMS). The 11 NPSs could be determined within 0.5 min by DART-MS. Furthermore, they could also be separated and determined within 5 min by the LC/QTOFMS method. The two methods both showed good linearity with correlation coefficients (r(2) ) higher than 0.99. The LODs for all these target NPSs by DART-MS and LC/QTOFMS ranged from 5 to 40 ng mL(-1) and 0.1 to 1 ng mL(-1) , respectively. Confiscated samples, named as "music vanilla" and "bath salt", and 11 spiked samples were firstly screened by DART-MS and then determined by LC/QTOFMS. The identification of NPSs in confiscated materials was successfully achieved, and the proposed analytical methodology could offer rapid screening and accurate analysis results. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
[Thoughts on optimizing the breast cancer screening strategies and implementation effects].
Wu, K J
2018-02-01
Reasonable and effective breast cancer screening can make early diagnosis of breast cancer, improve the cure rate, prolong survival and improve the patients' quality of life. China has made preliminary exploration and attempt in breast cancer screening, however, there are still some problems that have not been solved in terms of the proportion of opportunistic screening, the selection of screening targets, methods and frequency, and the judgment of screening results. Therefore, this article analyzes the above problems in details, and presents some thoughts and recommendations on how to optimize the breast cancer screening strategies and implementation effects in China, from the experience of clinical practice, under the background of constantly emerging new research results and techniques and the rapid development of artificial intelligence, that is, to adjust measures to local conditions, provide personalized strategies, achieve precise screening, preach and educate, ensure health insurance coverage, improve quality control, offer technical support and employ artificial intelligence.
Single-cell analysis of population context advances RNAi screening at multiple levels
Snijder, Berend; Sacher, Raphael; Rämö, Pauli; Liberali, Prisca; Mench, Karin; Wolfrum, Nina; Burleigh, Laura; Scott, Cameron C; Verheije, Monique H; Mercer, Jason; Moese, Stefan; Heger, Thomas; Theusner, Kristina; Jurgeit, Andreas; Lamparter, David; Balistreri, Giuseppe; Schelhaas, Mario; De Haan, Cornelis A M; Marjomäki, Varpu; Hyypiä, Timo; Rottier, Peter J M; Sodeik, Beate; Marsh, Mark; Gruenberg, Jean; Amara, Ali; Greber, Urs; Helenius, Ari; Pelkmans, Lucas
2012-01-01
Isogenic cells in culture show strong variability, which arises from dynamic adaptations to the microenvironment of individual cells. Here we study the influence of the cell population context, which determines a single cell's microenvironment, in image-based RNAi screens. We developed a comprehensive computational approach that employs Bayesian and multivariate methods at the single-cell level. We applied these methods to 45 RNA interference screens of various sizes, including 7 druggable genome and 2 genome-wide screens, analysing 17 different mammalian virus infections and four related cell physiological processes. Analysing cell-based screens at this depth reveals widespread RNAi-induced changes in the population context of individual cells leading to indirect RNAi effects, as well as perturbations of cell-to-cell variability regulators. We find that accounting for indirect effects improves the consistency between siRNAs targeted against the same gene, and between replicate RNAi screens performed in different cell lines, in different labs, and with different siRNA libraries. In an era where large-scale RNAi screens are increasingly performed to reach a systems-level understanding of cellular processes, we show that this is often improved by analyses that account for and incorporate the single-cell microenvironment. PMID:22531119
Etzioni, Ruth; Gulati, Roman
2013-04-01
In our article about limitations of basing screening policy on screening trials, we offered several examples of ways in which modeling, using data from large screening trials and population trends, provided insights that differed somewhat from those based only on empirical trial results. In this editorial, we take a step back and consider the general question of whether randomized screening trials provide the strongest evidence for clinical guidelines concerning population screening programs. We argue that randomized trials provide a process that is designed to protect against certain biases but that this process does not guarantee that inferences based on empirical results from screening trials will be unbiased. Appropriate quantitative methods are key to obtaining unbiased inferences from screening trials. We highlight several studies in the statistical literature demonstrating that conventional survival analyses of screening trials can be misleading and list a number of key questions concerning screening harms and benefits that cannot be answered without modeling. Although we acknowledge the centrality of screening trials in the policy process, we maintain that modeling constitutes a powerful tool for screening trial interpretation and screening policy development.
Microengineering methods for cell-based microarrays and high-throughput drug-screening applications.
Xu, Feng; Wu, JinHui; Wang, ShuQi; Durmus, Naside Gozde; Gurkan, Umut Atakan; Demirci, Utkan
2011-09-01
Screening for effective therapeutic agents from millions of drug candidates is costly, time consuming, and often faces concerns due to the extensive use of animals. To improve cost effectiveness, and to minimize animal testing in pharmaceutical research, in vitro monolayer cell microarrays with multiwell plate assays have been developed. Integration of cell microarrays with microfluidic systems has facilitated automated and controlled component loading, significantly reducing the consumption of the candidate compounds and the target cells. Even though these methods significantly increased the throughput compared to conventional in vitro testing systems and in vivo animal models, the cost associated with these platforms remains prohibitively high. Besides, there is a need for three-dimensional (3D) cell-based drug-screening models which can mimic the in vivo microenvironment and the functionality of the native tissues. Here, we present the state-of-the-art microengineering approaches that can be used to develop 3D cell-based drug-screening assays. We highlight the 3D in vitro cell culture systems with live cell-based arrays, microfluidic cell culture systems, and their application to high-throughput drug screening. We conclude that among the emerging microengineering approaches, bioprinting holds great potential to provide repeatable 3D cell-based constructs with high temporal, spatial control and versatility.
Determination of a Screening Metric for High Diversity DNA Libraries.
Guido, Nicholas J; Handerson, Steven; Joseph, Elaine M; Leake, Devin; Kung, Li A
2016-01-01
The fields of antibody engineering, enzyme optimization and pathway construction rely increasingly on screening complex variant DNA libraries. These highly diverse libraries allow researchers to sample a maximized sequence space; and therefore, more rapidly identify proteins with significantly improved activity. The current state of the art in synthetic biology allows for libraries with billions of variants, pushing the limits of researchers' ability to qualify libraries for screening by measuring the traditional quality metrics of fidelity and diversity of variants. Instead, when screening variant libraries, researchers typically use a generic, and often insufficient, oversampling rate based on a common rule-of-thumb. We have developed methods to calculate a library-specific oversampling metric, based on fidelity, diversity, and representation of variants, which informs researchers, prior to screening the library, of the amount of oversampling required to ensure that the desired fraction of variant molecules will be sampled. To derive this oversampling metric, we developed a novel alignment tool to efficiently measure frequency counts of individual nucleotide variant positions using next-generation sequencing data. Next, we apply a method based on the "coupon collector" probability theory to construct a curve of upper bound estimates of the sampling size required for any desired variant coverage. The calculated oversampling metric will guide researchers to maximize their efficiency in using highly variant libraries.
Microengineering Methods for Cell Based Microarrays and High-Throughput Drug Screening Applications
Xu, Feng; Wu, JinHui; Wang, ShuQi; Durmus, Naside Gozde; Gurkan, Umut Atakan; Demirci, Utkan
2011-01-01
Screening for effective therapeutic agents from millions of drug candidates is costly, time-consuming and often face ethical concerns due to extensive use of animals. To improve cost-effectiveness, and to minimize animal testing in pharmaceutical research, in vitro monolayer cell microarrays with multiwell plate assays have been developed. Integration of cell microarrays with microfluidic systems have facilitated automated and controlled component loading, significantly reducing the consumption of the candidate compounds and the target cells. Even though these methods significantly increased the throughput compared to conventional in vitro testing systems and in vivo animal models, the cost associated with these platforms remains prohibitively high. Besides, there is a need for three-dimensional (3D) cell based drug-screening models, which can mimic the in vivo microenvironment and the functionality of the native tissues. Here, we present the state-of-the-art microengineering approaches that can be used to develop 3D cell based drug screening assays. We highlight the 3D in vitro cell culture systems with live cell-based arrays, microfluidic cell culture systems, and their application to high-throughput drug screening. We conclude that among the emerging microengineering approaches, bioprinting holds a great potential to provide repeatable 3D cell based constructs with high temporal, spatial control and versatility. PMID:21725152
Stoutenbeek, R; Jansonius, N M
2006-01-01
Aim To determine the percentage of the population at risk of developing glaucoma, which can potentially be reached by conducting glaucoma screening during regular optician visits. Methods 1200 inhabitants aged >40 years were randomly selected from Dutch community population databases. A questionnaire was mailed to these inhabitants with questions on their latest optician visit and risk factors for glaucoma. A second questionnaire was sent to their opticians, who were asked about their willingness to conduct an additional glaucoma screening programme in the future. Results The questionnaire was returned by 959 of 1200 inhabitants and 37 of 50 opticians. The percentage of inhabitants who visited an optician during a 5‐year period was 83% (95% confidence interval (CI) 80% to 85%). This percentage was adjusted for the presence of risk factors for glaucoma to obtain the percentage of the population at risk of developing glaucoma. The percentage of opticians willing to cooperate in a glaucoma screening programme extended beyond a non‐contact tonometry measurement alone was 91% (95% CI 77% to 98%). Conclusion By conducting glaucoma screening during regular optician visits, a large section of the population at risk of developing glaucoma can be reached. PMID:16854829
An Automatic Quality Control Pipeline for High-Throughput Screening Hit Identification.
Zhai, Yufeng; Chen, Kaisheng; Zhong, Yang; Zhou, Bin; Ainscow, Edward; Wu, Ying-Ta; Zhou, Yingyao
2016-09-01
The correction or removal of signal errors in high-throughput screening (HTS) data is critical to the identification of high-quality lead candidates. Although a number of strategies have been previously developed to correct systematic errors and to remove screening artifacts, they are not universally effective and still require fair amount of human intervention. We introduce a fully automated quality control (QC) pipeline that can correct generic interplate systematic errors and remove intraplate random artifacts. The new pipeline was first applied to ~100 large-scale historical HTS assays; in silico analysis showed auto-QC led to a noticeably stronger structure-activity relationship. The method was further tested in several independent HTS runs, where QC results were sampled for experimental validation. Significantly increased hit confirmation rates were obtained after the QC steps, confirming that the proposed method was effective in enriching true-positive hits. An implementation of the algorithm is available to the screening community. © 2016 Society for Laboratory Automation and Screening.
Colquhoun, Heather L; Squires, Janet E; Kolehmainen, Niina; Fraser, Cynthia; Grimshaw, Jeremy M
2017-03-04
Systematic reviews consistently indicate that interventions to change healthcare professional (HCP) behaviour are haphazardly designed and poorly specified. Clarity about methods for designing and specifying interventions is needed. The objective of this review was to identify published methods for designing interventions to change HCP behaviour. A search of MEDLINE, Embase, and PsycINFO was conducted from 1996 to April 2015. Using inclusion/exclusion criteria, a broad screen of abstracts by one rater was followed by a strict screen of full text for all potentially relevant papers by three raters. An inductive approach was first applied to the included studies to identify commonalities and differences between the descriptions of methods across the papers. Based on this process and knowledge of related literatures, we developed a data extraction framework that included, e.g. level of change (e.g. individual versus organization); context of development; a brief description of the method; tasks included in the method (e.g. barrier identification, component selection, use of theory). 3966 titles and abstracts and 64 full-text papers were screened to yield 15 papers included in the review, each outlining one design method. All of the papers reported methods developed within a specific context. Thirteen papers included barrier identification and 13 included linking barriers to intervention components; although not the same 13 papers. Thirteen papers targeted individual HCPs with only one paper targeting change across individual, organization, and system levels. The use of theory and user engagement were included in 13/15 and 13/15 papers, respectively. There is an agreement across methods of four tasks that need to be completed when designing individual-level interventions: identifying barriers, selecting intervention components, using theory, and engaging end-users. Methods also consist of further additional tasks. Examples of methods for designing the organisation and system-level interventions were limited. Further analysis of design tasks could facilitate the development of detailed guidelines for designing interventions.
Vaez, Nara; Desgualdo-Pereira, Liliane; Paglialonga, Alessia
2014-01-01
This paper describes the development of a speech-in-noise test for hearing screening and surveillance in Brazilian Portuguese based on the evaluation of suprathreshold acuity performances. The SUN test (Speech Understanding in Noise) consists of a list of intervocalic consonants in noise presented in a multiple-choice paradigm by means of a touch screen. The test provides one out of three possible results: "a hearing check is recommended" (red light), "a hearing check would be advisable" (yellow light), and "no hearing difficulties" (green light) (Paglialonga et al., Comput. Biol. Med. 2014). This novel test was developed in a population of 30 normal hearing young adults and 101 adults with varying degrees of hearing impairment and handicap, including normal hearing. The test had 84% sensitivity and 76% specificity compared to conventional pure-tone screening and 83% sensitivity and 86% specificity to detect disabling hearing impairment. The test outcomes were in line with the degree of self-perceived hearing handicap. The results found here paralleled those reported in the literature for the SUN test and for conventional speech-in-noise measures. This study showed that the proposed test might be a viable method to identify individuals with hearing problems to be referred to further audiological assessment and intervention.
Mass spectrometry-driven drug discovery for development of herbal medicine.
Zhang, Aihua; Sun, Hui; Wang, Xijun
2018-05-01
Herbal medicine (HM) has made a major contribution to the drug discovery process with regard to identifying products compounds. Currently, more attention has been focused on drug discovery from natural compounds of HM. Despite the rapid advancement of modern analytical techniques, drug discovery is still a difficult and lengthy process. Fortunately, mass spectrometry (MS) can provide us with useful structural information for drug discovery, has been recognized as a sensitive, rapid, and high-throughput technology for advancing drug discovery from HM in the post-genomic era. It is essential to develop an efficient, high-quality, high-throughput screening method integrated with an MS platform for early screening of candidate drug molecules from natural products. We have developed a new chinmedomics strategy reliant on MS that is capable of capturing the candidate molecules, facilitating their identification of novel chemical structures in the early phase; chinmedomics-guided natural product discovery based on MS may provide an effective tool that addresses challenges in early screening of effective constituents of herbs against disease. This critical review covers the use of MS with related techniques and methodologies for natural product discovery, biomarker identification, and determination of mechanisms of action. It also highlights high-throughput chinmedomics screening methods suitable for lead compound discovery illustrated by recent successes. © 2016 Wiley Periodicals, Inc.
NASA flight electronics environmental stress screening survey
NASA Technical Reports Server (NTRS)
Marian, E. J. (Compiler)
1983-01-01
Data compiled by the Institute of Environmental Sciences were used to establish guidelines for identifying defective, abnormal, or marginal parts as well as manufacturing defects. These data are augmented with other available sources of similar information in conjunction with NASA centers' data and presented in a form that may be useful to all NASA centers in planning and developing effective environmental stress screens. Information relative to thermal and vibration screens as the most effective methods for surfacing latent failures in electronic equipment at the component level is considered.
CrossCheck: an open-source web tool for high-throughput screen data analysis.
Najafov, Jamil; Najafov, Ayaz
2017-07-19
Modern high-throughput screening methods allow researchers to generate large datasets that potentially contain important biological information. However, oftentimes, picking relevant hits from such screens and generating testable hypotheses requires training in bioinformatics and the skills to efficiently perform database mining. There are currently no tools available to general public that allow users to cross-reference their screen datasets with published screen datasets. To this end, we developed CrossCheck, an online platform for high-throughput screen data analysis. CrossCheck is a centralized database that allows effortless comparison of the user-entered list of gene symbols with 16,231 published datasets. These datasets include published data from genome-wide RNAi and CRISPR screens, interactome proteomics and phosphoproteomics screens, cancer mutation databases, low-throughput studies of major cell signaling mediators, such as kinases, E3 ubiquitin ligases and phosphatases, and gene ontological information. Moreover, CrossCheck includes a novel database of predicted protein kinase substrates, which was developed using proteome-wide consensus motif searches. CrossCheck dramatically simplifies high-throughput screen data analysis and enables researchers to dig deep into the published literature and streamline data-driven hypothesis generation. CrossCheck is freely accessible as a web-based application at http://proteinguru.com/crosscheck.
Lagarde, Nathalie; Zagury, Jean-François; Montes, Matthieu
2015-07-27
Virtual screening methods are commonly used nowadays in drug discovery processes. However, to ensure their reliability, they have to be carefully evaluated. The evaluation of these methods is often realized in a retrospective way, notably by studying the enrichment of benchmarking data sets. To this purpose, numerous benchmarking data sets were developed over the years, and the resulting improvements led to the availability of high quality benchmarking data sets. However, some points still have to be considered in the selection of the active compounds, decoys, and protein structures to obtain optimal benchmarking data sets.
Monocular display unit for 3D display with correct depth perception
NASA Astrophysics Data System (ADS)
Sakamoto, Kunio; Hosomi, Takashi
2009-11-01
A study of virtual-reality system has been popular and its technology has been applied to medical engineering, educational engineering, a CAD/CAM system and so on. The 3D imaging display system has two types in the presentation method; one is a 3-D display system using a special glasses and the other is the monitor system requiring no special glasses. A liquid crystal display (LCD) recently comes into common use. It is possible for this display unit to provide the same size of displaying area as the image screen on the panel. A display system requiring no special glasses is useful for a 3D TV monitor, but this system has demerit such that the size of a monitor restricts the visual field for displaying images. Thus the conventional display can show only one screen, but it is impossible to enlarge the size of a screen, for example twice. To enlarge the display area, the authors have developed an enlarging method of display area using a mirror. Our extension method enables the observers to show the virtual image plane and to enlarge a screen area twice. In the developed display unit, we made use of an image separating technique using polarized glasses, a parallax barrier or a lenticular lens screen for 3D imaging. The mirror can generate the virtual image plane and it enlarges a screen area twice. Meanwhile the 3D display system using special glasses can also display virtual images over a wide area. In this paper, we present a monocular 3D vision system with accommodation mechanism, which is useful function for perceiving depth.
Tuberculosis screening of migrants to low-burden nations: insights from evaluation of UK practice.
Pareek, M; Abubakar, I; White, P J; Garnett, G P; Lalvani, A
2011-05-01
Tuberculosis (TB) primarily occurs in the foreign-born in European countries, such as the UK, where increasing notifications and the high proportion of foreign-born cases has refocused attention on immigrant (new entrant) screening. We investigated how UK primary care organisations (PCOs) screen new entrants and whether this differs according to TB burden in the PCOs (incidence < 20 or ≥ 20 cases per 100,000 per annum). An anonymous, 20-point questionnaire was sent to all 192 UK PCOs asking which new entrants are screened, who is screened for active TB/latent TB infection (LTBI) and the methods used. Descriptive analyses were undertaken. Categorical responses were compared using the Chi-squared test. 177 (92.2%) out of 192 PCOs responded; all undertook screening action in response to abnormal chest radiographs, but only 107 (60.4%) screened new entrants for LTBI. Few new entrants had active TB diagnosed (median 0.0%, interquartile range (IQR) 0.0-0.5%) but more were identified with LTBI (median 7.85%, IQR 4.30-13.50%). High-burden PCOs were significantly less likely to screen new entrants for LTBI (OR 0.26, 95% CI 0.12-0.54; p<0.0001). Among PCOs screening for LTBI, there was substantial deviation from national guidance in selection of new entrant subgroups and screening method. Considerable heterogeneity and deviation from national guidance exist throughout the UK new entrant screening process, with high-burden regions undertaking the least screening. Forming an accurate picture of current front-line practice will help to inform future development of European new entrant screening policy.
Owens, D K; Nease, R F
1993-07-01
The growth in guidance development projects has focused attention on the methods used in developing the guideline. For a guideline to be sound it should be linked on the basis of scientific evidence to the very health outcome that the guideline is designed to promote. Structuring a health intervention as an influence diagram, a decision model (1) allows for the identification of the relevant benefits, harms, and costs that may result from an intervention; (2) provides an explicit link between the intervention and these outcomes, a crucial prerequisite for the development of an outcome-based guideline; and (3) identifies the evidence that must be synthesized to predict the effect of the intervention on the health outcomes. In the development of a guideline related to prevention of opportunistic infections in HIV-infected persons, we would define the interventions (for example, use of medication for PCP pneumonia), the intended health outcome (a potential reduction in the number of opportunistic infections), and the evidence that demonstrates that the intervention produces the desired outcome. If PCP prophylaxis is delayed, the HIV-infected person is exposed to a undue risk of PCP, with its attendant morbidity and mortality. If it is initiated too early, the person incurs excess monetary costs and may experience additional side-effect-associated morbidity. The intervention in question is screening for HIV infection, and the outcomes of interest are the medical benefits and harms associated with screening and the financial costs (and savings) that a screening program would incur. Screening for HIV infection differs from many clinical questions because it has potential benefit both to the persons screened and to public health if the screened person reduces risk behaviors that might transmit HIV infection. Structuring a problem with an influence diagram: delineates an explicit link between interventions and outcomes; focuses the questions to be addressed (a series of more sharply defined questions, each of which we may be able to answer based on direct evidence, replaces a much broader question [should we screen for HIV?], which cannot be answered directly); and highlights the importance of a clear, unambiguous statement whose benefit and costs are under consideration.
2010-01-01
Background Competing causes of mortality in the elderly decrease the potential net benefit from colorectal cancer screening and increase the likelihood of potential harms. Individualized decision making has been recommended, so that the elderly can decide whether or not to undergo colorectal cancer (CRC) screening. The objective is to develop and test a decision aid designed to promote individualized colorectal cancer screening decision making for adults age 75 and over. Methods We used formative research and cognitive testing to develop and refine the decision aid. We then tested the decision aid in an uncontrolled trial. The primary outcome was the proportion of patients who were prepared to make an individualized decision, defined a priori as having adequate knowledge (10/15 questions correct) and clear values (25 or less on values clarity subscale of decisional conflict scale). Secondary outcomes included overall score on the decisional conflict scale, and preferences for undergoing screening. Results We enrolled 46 adults in the trial. The decision aid increased the proportion of participants with adequate knowledge from 4% to 52% (p < 0.01) and the proportion prepared to make an individualized decision from 4% to 41% (p < 0.01). The proportion that preferred to undergo CRC screening decreased from 67% to 61% (p = 0. 76); 7 participants (15%) changed screening preference (5 against screening, 2 in favor of screening) Conclusion In an uncontrolled trial, the elderly participants appeared better prepared to make an individualized decision about whether or not to undergo CRC screening after using the decision aid. PMID:20849625
Assessment of circulating copy number variant detection for cancer screening.
Molparia, Bhuvan; Nichani, Eshaan; Torkamani, Ali
2017-01-01
Current high-sensitivity cancer screening methods, largely utilizing correlative biomarkers, suffer from false positive rates that lead to unnecessary medical procedures and debatable public health benefit overall. Detection of circulating tumor DNA (ctDNA), a causal biomarker, has the potential to revolutionize cancer screening. Thus far, the majority of ctDNA studies have focused on detection of tumor-specific point mutations after cancer diagnosis for the purpose of post-treatment surveillance. However, ctDNA point mutation detection methods developed to date likely lack either the scope or analytical sensitivity necessary to be useful for cancer screening, due to the low (<1%) ctDNA fraction derived from early stage tumors. On the other hand, tumor-derived copy number variant (CNV) detection is hypothetically a superior means of ctDNA-based cancer screening for many tumor types, given that, relative to point mutations, each individual tumor CNV contributes a much larger number of ctDNA fragments to the overall pool of circulating free DNA (cfDNA). A small number of studies have demonstrated the potential of ctDNA CNV-based screening in select cancer types. Here we perform an in silico assessment of the potential for ctDNA CNV-based cancer screening across many common cancers, and suggest ctDNA CNV detection shows promise as a broad cancer screening methodology.
Clinical guideline representation in a CDS: a human information processing method.
Kilsdonk, Ellen; Riezebos, Rinke; Kremer, Leontien; Peute, Linda; Jaspers, Monique
2012-01-01
The Dutch Childhood Oncology Group (DCOG) has developed evidence-based guidelines for screening childhood cancer survivors for possible late complications of treatment. These paper-based guidelines appeared to not suit clinicians' information retrieval strategies; it was thus decided to communicate the guidelines through a Computerized Decision Support (CDS) tool. To ensure high usability of this tool, an analysis of clinicians' cognitive strategies in retrieving information from the paper-based guidelines was used as requirements elicitation method. An information processing model was developed through an analysis of think aloud protocols and used as input for the design of the CDS user interface. Usability analysis of the user interface showed that the navigational structure of the CDS tool fitted well with the clinicians' mental strategies employed in deciding on survivors screening protocols. Clinicians were more efficient and more complete in deciding on patient-tailored screening procedures when supported by the CDS tool than by the paper-based guideline booklet. The think-aloud method provided detailed insight into users' clinical work patterns that supported the design of a highly usable CDS system.
The development of multi-well microelectrode array (mwMEA) systems has increased in vitro screening throughput making them an effective method to screen and prioritize large sets of compounds for potential neurotoxicity. In the present experiments, a multiplexed approach was used...
Rogers, Michelle L.; Armstrong, Gene F.; Rakowski, William; Bowen, Deborah J.; Hughes, Tonda; McGarry, Kelly A.
2009-01-01
Abstract Objectives We explored self-reported rates of individual on-schedule breast, cervical, and colorectal cancer screenings, as well as an aggregate measure of comprehensive screenings, among unmarried women aged 40–75 years. We compared women who partner with women (WPW) or with women and men (WPWM) to women who partner exclusively with men (WPM). We also compared barriers to on-schedule cancer screenings between WPW/WPWM and WPM. Methods Comparable targeted and respondent-driven sampling methods were used to enroll 213 WPW/WPWM and 417 WPM (n = 630). Logistic regression models were computed to determine if partner gender was associated with each measure of on-schedule screening after controlling for demographic characteristics, health behaviors, and cancer-related experiences. Results Overall, 74.3% of women reported on-schedule breast screening, 78.3% reported on-schedule cervical screening, 66.5% reported on-schedule colorectal screening, and 56.7% reported being on-schedule for comprehensive screening. Partner gender was not associated with any of the measures of on-schedule screening in multivariable analyses. However, women who reported ever putting off, avoiding, or changing the place of screenings because of sexual orientation were less likely to be on-schedule for comprehensive screening. Women who reported barriers associated with taking time from work and body image concerns were also less likely to be on-schedule for comprehensive screening. Conclusions Barriers to cancer screening were comparable across types of examinations as well as between WPW/WPWM and WPM. Developing health promotion programs for unmarried women that address concomitant detection and prevention behaviors may improve the efficiency and effectiveness of healthcare delivery and ultimately assist in reducing multiple disease risks. PMID:19361311
Oplatowska-Stachowiak, Michalina; Sajic, Nermin; Haasnoot, Willem; Campbell, Katrina; Elliott, Christopher T.; Salden, Martin
2017-01-01
T-2 toxin/HT-2 toxin (T-2/HT-2) and ochratoxin A (OTA) are mycotoxins that can contaminate a variety of agricultural commodities. To protect consumers’ health, indicative limits for T-2/HT-2 and maximum limits for OTA have been set by the European Commission, requiring food business operators and controlling agencies to conduct routine checks for the presence of these harmful contaminants. Screening methods are increasingly used for monitoring purposes. Due to the demand for new and improved screening tools, two individual detection methods, T-2/HT-2 and OTA enzyme-linked immunosorbent assays (ELISAs), were developed in this study. The T-2/HT-2 ELISA was based on a T-2 monoclonal antibody with an IC50 (50% inhibitory concentration) of 0.28 ng/mL and 125% cross-reactivity with HT-2. As regards the OTA ELISA, a new sensitive monoclonal antibody specific to OTA with an IC50 of 0.13 ng/mL was produced. Both developed ELISA tests were then validated in agricultural commodities in accordance with the new performance criteria guidelines for the validation of screening methods for mycotoxins included in Commission Regulation (EU) No 519/2014. The T-2/HT-2 ELISA was demonstrated to be suitable for the detection of T-2/HT-2 in cereals and baby food at and above the screening target concentration (STC) of 12.5 μg/kg and 7.5 μg/kg, respectively. The OTA ELISA was shown to be applicable for the detection of OTA in cereals, coffee, cocoa and wine at and above the STC of 2 μg/kg, 2.5 μg/kg, 2.5 μg/kg and 0.4 ng/mL, respectively. The accuracy of both ELISAs was further confirmed by analysing proficiency test and reference samples. The developed methods can be used for sensitive and high-throughput screening for the presence of T-2/HT-2 and OTA in agricultural commodities. PMID:29189752
Oplatowska-Stachowiak, Michalina; Kleintjens, Tim; Sajic, Nermin; Haasnoot, Willem; Campbell, Katrina; Elliott, Christopher T; Salden, Martin
2017-11-30
T-2 toxin/HT-2 toxin (T-2/HT-2) and ochratoxin A (OTA) are mycotoxins that can contaminate a variety of agricultural commodities. To protect consumers' health, indicative limits for T-2/HT-2 and maximum limits for OTA have been set by the European Commission, requiring food business operators and controlling agencies to conduct routine checks for the presence of these harmful contaminants. Screening methods are increasingly used for monitoring purposes. Due to the demand for new and improved screening tools, two individual detection methods, T-2/HT-2 and OTA enzyme-linked immunosorbent assays (ELISAs), were developed in this study. The T-2/HT-2 ELISA was based on a T-2 monoclonal antibody with an IC 50 (50% inhibitory concentration) of 0.28 ng/mL and 125% cross-reactivity with HT-2. As regards the OTA ELISA, a new sensitive monoclonal antibody specific to OTA with an IC 50 of 0.13 ng/mL was produced. Both developed ELISA tests were then validated in agricultural commodities in accordance with the new performance criteria guidelines for the validation of screening methods for mycotoxins included in Commission Regulation (EU) No 519/2014. The T-2/HT-2 ELISA was demonstrated to be suitable for the detection of T-2/HT-2 in cereals and baby food at and above the screening target concentration (STC) of 12.5 μg/kg and 7.5 μg/kg, respectively. The OTA ELISA was shown to be applicable for the detection of OTA in cereals, coffee, cocoa and wine at and above the STC of 2 μg/kg, 2.5 μg/kg, 2.5 μg/kg and 0.4 ng/mL, respectively. The accuracy of both ELISAs was further confirmed by analysing proficiency test and reference samples. The developed methods can be used for sensitive and high-throughput screening for the presence of T-2/HT-2 and OTA in agricultural commodities.
Novel approaches for targeting the adenosine A2A receptor.
Yuan, Gengyang; Gedeon, Nicholas G; Jankins, Tanner C; Jones, Graham B
2015-01-01
The adenosine A2A receptor (A2AR) represents a drug target for a wide spectrum of diseases. Approaches for targeting this membrane-bound protein have been greatly advanced by new stabilization techniques. The resulting X-ray crystal structures and subsequent analyses provide deep insight to the A2AR from both static and dynamic perspectives. Application of this, along with other biophysical methods combined with fragment-based drug design (FBDD), has become a standard approach in targeting A2AR. Complementarities of in silico screening based- and biophysical screening assisted- FBDD are likely to feature in future approaches in identifying novel ligands against this key receptor. This review describes evolution of the above approaches for targeting A2AR and highlights key modulators identified. It includes a review of: adenosine receptor structures, homology modeling, X-ray structural analysis, rational drug design, biophysical methods, FBDD and in silico screening. As a drug target, the A2AR is attractive as its function plays a role in a wide spectrum of diseases including oncologic, inflammatory, Parkinson's and cardiovascular diseases. Although traditional approaches such as high-throughput screening and homology model-based virtual screening (VS) have played a role in targeting A2AR, numerous shortcomings have generally restricted their applications to specific ligand families. Using stabilization methods for crystallization, X-ray structures of A2AR have greatly accelerated drug discovery and influenced development of biophysical-in silico hybrid screening methods. Application of these new methods to other ARs and G-protein-coupled receptors is anticipated in the future.
EPA is developing methods for utilizing computational chemistry, high-throughput screening (HTS)and genomic technologies to predict potential toxicity and prioritize the use of limited testing resources.
Binding-Site Assessment by Virtual Fragment Screening
Huang, Niu; Jacobson, Matthew P.
2010-01-01
The accurate prediction of protein druggability (propensity to bind high-affinity drug-like small molecules) would greatly benefit the fields of chemical genomics and drug discovery. We have developed a novel approach to quantitatively assess protein druggability by computationally screening a fragment-like compound library. In analogy to NMR-based fragment screening, we dock ∼11000 fragments against a given binding site and compute a computational hit rate based on the fraction of molecules that exceed an empirically chosen score cutoff. We perform a large-scale evaluation of the approach on four datasets, totaling 152 binding sites. We demonstrate that computed hit rates correlate with hit rates measured experimentally in a previously published NMR-based screening method. Secondly, we show that the in silico fragment screening method can be used to distinguish known druggable and non-druggable targets, including both enzymes and protein-protein interaction sites. Finally, we explore the sensitivity of the results to different receptor conformations, including flexible protein-protein interaction sites. Besides its original aim to assess druggability of different protein targets, this method could be used to identifying druggable conformations of flexible binding site for lead discovery, and suggesting strategies for growing or joining initial fragment hits to obtain more potent inhibitors. PMID:20404926
Solid-phase assays for small molecule screening using sol-gel entrapped proteins.
Lebert, Julie M; Forsberg, Erica M; Brennan, John D
2008-04-01
With compound libraries exceeding one million compounds, the ability to quickly and effectively screen these compounds against relevant pharmaceutical targets has become crucial. Solid-phase assays present several advantages over solution-based methods. For example, a higher degree of miniaturization can be achieved, functional- and affinity-based studies are possible, and a variety of detection methods can be used. Unfortunately, most protein immobilization methods are either too harsh or require recombinant proteins and thus are not amenable to delicate proteins such as kinases and membrane-bound receptors. Sol-gel encapsulation of proteins in an inorganic silica matrix has emerged as a novel solid-phase assay platform. In this minireview, we discuss the development of sol-gel derived protein microarrays and sol-gel based monolithic bioaffinity columns for the high-throughput screening of small molecule libraries and mixtures.
Heller, David N; Nochetto, Cristina B; Rummel, Nathan G; Thomas, Michael H
2006-07-26
A method was developed for detection of a variety of polar drug residues in eggs via liquid chromatography/tandem mass spectrometry (LC/MS/MS) with electrospray ionization (ESI). A total of twenty-nine target analytes from four drug classes-sulfonamides, tetracyclines, fluoroquinolones, and beta-lactams-were extracted from eggs using a hydrophilic-lipophilic balance polymer solid-phase extraction (SPE) cartridge. The extraction technique was developed for use at a target concentration of 100 ng/mL (ppb), and it was applied to eggs containing incurred residues from dosed laying hens. The ESI source was tuned using a single, generic set of tuning parameters, and analytes were separated with a phenyl-bonded silica cartridge column using an LC gradient. In a related study, residues of beta-lactam drugs were not found by LC/MS/MS in eggs from hens dosed orally with beta-lactam drugs. LC/MS/MS performance was evaluated on two generations of ion trap mass spectrometers, and key operational parameters were identified for each instrument. The ion trap acquisition methods could be set up for screening (a single product ion) or confirmation (multiple product ions). The lower limit of detection for screening purposes was 10-50 ppb (sulfonamides), 10-20 ppb (fluoroquinolones), and 10-50 ppb (tetracyclines), depending on the drug, instrument, and acquisition method. Development of this method demonstrates the feasibility of generic SPE, LC, and MS conditions for multiclass LC/MS residue screening.
Betancourt, Hector; Flynn, Patricia M.; Riggs, Matt; Garberoglio, Carlos
2010-01-01
To illustrate the implementation of a bottom-up approach to the study of culture in health disparities, this article describes the development of a cultural cancer screening scale (CCSS) using mixed methodologies. The aim was to identify cultural factors relevant to breast and cervical cancer screening, develop an instrument to assess them and examine its preliminary psychometric properties among Latin American (Latino) and non-Latino White (Anglo) women in Southern California. Seventy-eight Latino and Anglo women participated in semi-structured interviews, which were content coded based on Triandis' methods for the analysis of subjective culture. Based on the emerging cultural elements, items relevant to cancer screening were developed and pilot tested with 161 participants. After the instrument was refined, 314 Latino and Anglo women from various socioeconomic backgrounds completed the CCSS and data were factor analyzed resulting in five cultural factors: cancer screening fatalism, negative beliefs about health professionals, catastrophic disease expectations, symptomatic deterrents and sociocultural deterrents. The instrument demonstrated measurement equivalence, adequate reliability and predictive validity. The research and the CCSS are discussed in terms of implications for the study of culture in relation to health disparities and the development of evidence-based interventions with culturally diverse populations and their health professionals. PMID:20864605
Serra, Yolanda A; Colón-López, Vivian; Savas, Lara S; Vernon, Sally W; Fernández-Espada, Natalie; Vélez, Camille; Ayala, Alelí; Fernández, María E
2017-01-01
Colorectal cancer (CRC) is a leading cause of cancer-related mortality in Puerto Rico (PR). Although largely preventable through screening and treatment of precancerous polyps, CRC screening rates in PR remain low while CRC incidence and mortality continue to increase. We used intervention mapping (IM), a systematic framework using theory and evidence to plan a health promotion intervention to increase colorectal cancer screening (CRCS) among Puerto Rican adults 50 years and older who are patients of Federally Qualified Health Centers (FQHCs) in PR. To inform the development of a logic model of the problem during the needs assessment phase, we determined the CRC incidence and mortality rates in PR using recent data from the PR Cancer Registry, conducted a literature review to better understand behavioral and environmental factors influencing CRC among Hispanics in general and in Puerto Ricans, and collected new data. We conducted seven focus groups to identify community needs and resources, specific sub-behaviors related to CRCS (performance objectives) and the determinants of CRCS. We then developed matrices of change objectives that would guide the content, behavioral change method selection, and the practical applications that would be included in the program. We selected two overarching methods: entertainment education and behavioral journalism and developed practical applications, materials, and messages containing several other methods including modeling, persuasion, information, and tailoring. We developed and pretested a Tailored Interactive Multimedia Intervention, newsletter, an action plan, and supplemental print materials for patients. We also developed a patient mediated provider prompt to increase provider recommendation and improve patient provider communication. The use of IM for systematic planning produced a detailed coherent plan for the CRCS educational intervention. Guided by IM processes, steps, and tasks, we used community level information, existing literature, theory, and new data to develop health education materials that were well received by the priority population and will likely increase CRCS among FQHC patients in PR.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nyholm, N.; Kristensen, P.
1992-04-01
An international ring test involving 14 laboratories was organized on behalf of the Commission of the European Economic Communities (EEC) with the purpose of evaluating two proposed screening methods for assessment of biodegradability in seawater: (a) a shake flask die-away test based primarily on analysis of dissolved organic carbon and (b) a closed bottle test based on determination of dissolved oxygen. Both tests are performed with nutrient-enriched natural seawater as the test medium and with no inoculum added other than the natural seawater microflora. The test methods are seawater versions of the modified OECD screening test and the closed bottlemore » test, respectively, adopted by the Organization for Economic Cooperation and Development (OECD) and by the EEC as tests for ready biodegradability.' The following five chemicals were examined: sodium benzoate, aniline, diethylene glycol, pentaerythritol, and 4-nitrophenol. Sodium benzoate and aniline, which are known to be generally readily biodegradable consistently degraded in practically all tests, thus demonstrating the technical feasibility of the methods. Like in previous ring tests with freshwater screening methods variable results were obtained with the other three compounds, which is believed primarily to be due to site-specific differences between the microflora of the different seawater samples used and to some extent also to differences in the applied concentrations of test material. A positive result with the screening methods indicates that the test substance will most likely degrade relatively rapidly in seawater from the site of collection, while a negative test result does not preclude biodegradability under environmental conditions where the concentrations of chemicals are much lower than the concentrations applied for analytical reasons in screening tests.« less
Natural Language Processing As an Alternative to Manual Reporting of Colonoscopy Quality Metrics
RAJU, GOTTUMUKKALA S.; LUM, PHILLIP J.; SLACK, REBECCA; THIRUMURTHI, SELVI; LYNCH, PATRICK M.; MILLER, ETHAN; WESTON, BRIAN R.; DAVILA, MARTA L.; BHUTANI, MANOOP S.; SHAFI, MEHNAZ A.; BRESALIER, ROBERT S.; DEKOVICH, ALEXANDER A.; LEE, JEFFREY H.; GUHA, SUSHOVAN; PANDE, MALA; BLECHACZ, BORIS; RASHID, ASIF; ROUTBORT, MARK; SHUTTLESWORTH, GLADIS; MISHRA, LOPA; STROEHLEIN, JOHN R.; ROSS, WILLIAM A.
2015-01-01
BACKGROUND & AIMS The adenoma detection rate (ADR) is a quality metric tied to interval colon cancer occurrence. However, manual extraction of data to calculate and track the ADR in clinical practice is labor-intensive. To overcome this difficulty, we developed a natural language processing (NLP) method to identify patients, who underwent their first screening colonoscopy, identify adenomas and sessile serrated adenomas (SSA). We compared the NLP generated results with that of manual data extraction to test the accuracy of NLP, and report on colonoscopy quality metrics using NLP. METHODS Identification of screening colonoscopies using NLP was compared with that using the manual method for 12,748 patients who underwent colonoscopies from July 2010 to February 2013. Also, identification of adenomas and SSAs using NLP was compared with that using the manual method with 2259 matched patient records. Colonoscopy ADRs using these methods were generated for each physician. RESULTS NLP correctly identified 91.3% of the screening examinations, whereas the manual method identified 87.8% of them. Both the manual method and NLP correctly identified examinations of patients with adenomas and SSAs in the matched records almost perfectly. Both NLP and manual method produce comparable values for ADR for each endoscopist as well as the group as a whole. CONCLUSIONS NLP can correctly identify screening colonoscopies, accurately identify adenomas and SSAs in a pathology database, and provide real-time quality metrics for colonoscopy. PMID:25910665
Fernández, Maria E; Gonzales, Alicia; Tortolero-Luna, Guillermo; Partida, Sylvia; Bartholomew, L Kay
2005-10-01
This article describes the development of the Cultivando La Salud program, an intervention to increase breast and cervical cancer screening for Hispanic farmworker women. Processes and findings of intervention mapping (IM), a planning process for development of theory and evidence-informed program are discussed. The six IM steps are presented: needs assessment, preparation of planning matrices, election of theoretic methods and practical strategies, program design, implementation planning, and evaluation. The article also describes how qualitative and quantitative findings informed intervention development. IM helped ensure that theory and evidence guided (a) the identification of behavioral and environmental factors related to a target health problem and (b) the selection of the most appropriate methods and strategies to address the identified determinants. IM also guided the development of program materials and implementation by lay health workers. Also reported are findings of the pilot study and effectiveness trial.
Reducing Youth Screen Time: Qualitative Metasynthesis of Findings on Barriers and Facilitators
Minges, Karl E.; Salmon, Jo; Dunstan, David W.; Owen, Neville; Chao, Ariana; Whittemore, Robin
2015-01-01
Objective An integrated perspective on the relevant qualitative findings on the experience of screen time in youth can inform the development of hypotheses to be tested in future research and can guide the development of interventions to decrease sedentary behavior. The purpose of this qualitative metasynthesis was to explore parent, youth, and educational professionals’ perceptions of barriers to, and facilitators of, reducing youth screen time. Method Qualitative metasynthesis techniques were used to analyze and synthesize 15 qualitative studies of screen time among youth (11–18 years) meeting inclusion criteria. The phrases, quotes, and/or author interpretations (i.e., theme or subtheme) were recorded in a data display matrix to facilitate article comparisons. Codes were collapsed into 23 categories of similar conceptual meaning and 3 overarching themes were derived using thematic analysis procedures. Results Study sample sizes ranged from 6 to 270 participants from 6 countries. Data collection methods included focus groups (n = 6), interviews (n = 4), focus group and interviews (n = 4), and naturalistic observation (n = 1) with youth and/or parents. Data analysis techniques included thematic analysis (n = 9), content analysis (n = 3), grounded theory (n = 1), observation (n = 1), and interpretive phenomenological analysis (n = 1). Three thematic categories were identified: (a) youth’s norms—screen time is an integral part of daily life, and facilitates opportunities for entertainment, social interaction, and escapism; (b) family dynamics and parental roles—parents are conflicted and send mixed messages about the appropriate uses and amounts of screen time; and, (c) resources and environment—engagement in screen time is dependent on school, community, neighborhood, and home environmental contexts. Conclusions Screen time is an established norm in many youth cultures, presenting barriers to behavior change. Parents recognize the importance of reducing youth screen time, but model and promote engagement themselves. For youth and parents, mutually agreed rules, limits, and parental monitoring of screen time were perceived as likely to be effective. PMID:25822054
Frederiks, T M; Christopher, J T; Harvey, G L; Sutherland, M W; Borrell, A K
2012-09-01
Cereal crops can suffer substantial damage if frosts occur at heading. Identification of post-head-emergence frost (PHEF) resistance in cereals poses a number of unique and difficult challenges. Many decades of research have failed to identify genotypes with PHEF resistance that could offer economically significant benefit to growers. Research and breeding gains have been limited by the available screening systems. Using traditional frost screening systems, genotypes that escape frost injury in trials due to spatial temperature differences and/or small differences in phenology can be misidentified as resistant. We believe that by improving techniques to minimize frost escapes, such 'false-positive' results can be confidently identified and eliminated. Artificial freezing chambers or manipulated natural frost treatments offer many potential advantages but are not yet at the stage where they can be reliably used for frost screening in breeding programmes. Here we describe the development of a novel photoperiod gradient method (PGM) that facilitates screening of genotypes of different phenology under natural field frosts at matched developmental stages. By identifying frost escapes and increasing the efficiency of field screening, the PGM ensures that research effort can be focused on finding genotypes with improved PHEF resistance. To maximize the likelihood of identifying PHEF resistance, we propose that the PGM form part of an integrated strategy to (i) source germplasm;(ii) facilitate high throughput screening; and (iii) permit detailed validation. PGM may also be useful in other studies where either a range of developmental stages and/or synchronized development are desired.
Display screen and method of manufacture therefor
NASA Technical Reports Server (NTRS)
Dubin, Matthew B. (Inventor); Larson, Brent D. (Inventor)
2002-01-01
A screen assembly that combines an angle re-distributing prescreen with a conventional diffusion screen. The prescreen minimizes or eliminates the sensitivity of the screen assembly to projector location. The diffusion screen provides other desirable screen characteristics. Compatible screen structures, along with methods for fabricating high resolution prescreens and methods and devices for maintaining the desired relationship between the prescreen and the diffusion screen are contemplated.
A developmental screening tool for toddlers with multiple domains based on Rasch analysis.
Hwang, Ai-Wen; Chou, Yeh-Tai; Hsieh, Ching-Lin; Hsieh, Wu-Shiun; Liao, Hua-Fang; Wong, Alice May-Kuen
2015-01-01
Using multidomain developmental screening tools is a feasible method for pediatric health care professionals to identify children at risk of developmental problems in multiple domains simultaneously. The purpose of this study was to develop a Rasch-based tool for Multidimensional Screening in Child Development (MuSiC) for children aged 0-3 years. The MuSic was developed by constructing items bank based on three commonly used screening tools, validating with developmental status (at risk for delay or not) on five developmental domains. Parents of a convenient sample of 632 children (aged 3-35.5 months) with and without developmental delays responded to items from the three screening tools funded by health authorities in Taiwan. Item bank was determined by item fit of Rasch analysis for each of the five developmental domains (cognitive skills, language skills, gross motor skills, fine motor skills, and socioadaptive skills). Children's performance scores in logits derived in Rasch analysis were validated with developmental status for each domain using the area under receiver operating characteristic curves. MuSiC, a 75-item developmental screening tool for five domains, was derived. The diagnostic validity of all five domains was acceptable for all stages of development, except for the infant stage (≤11 months and 15 days). MuSiC can be applied simultaneously to well-child care visits as a universal screening tool for children aged 1-3 years on multiple domains. Items with sound validity for infants need to be further developed. Copyright © 2014. Published by Elsevier B.V.
Dresen, S; Ferreirós, N; Gnann, H; Zimmermann, R; Weinmann, W
2010-04-01
The multi-target screening method described in this work allows the simultaneous detection and identification of 700 drugs and metabolites in biological fluids using a hybrid triple-quadrupole linear ion trap mass spectrometer in a single analytical run. After standardization of the method, the retention times of 700 compounds were determined and transitions for each compound were selected by a "scheduled" survey MRM scan, followed by an information-dependent acquisition using the sensitive enhanced product ion scan of a Q TRAP hybrid instrument. The identification of the compounds in the samples analyzed was accomplished by searching the tandem mass spectrometry (MS/MS) spectra against the library we developed, which contains electrospray ionization-MS/MS spectra of over 1,250 compounds. The multi-target screening method together with the library was included in a software program for routine screening and quantitation to achieve automated acquisition and library searching. With the help of this software application, the time for evaluation and interpretation of the results could be drastically reduced. This new multi-target screening method has been successfully applied for the analysis of postmortem and traffic offense samples as well as proficiency testing, and complements screening with immunoassays, gas chromatography-mass spectrometry, and liquid chromatography-diode-array detection. Other possible applications are analysis in clinical toxicology (for intoxication cases), in psychiatry (antidepressants and other psychoactive drugs), and in forensic toxicology (drugs and driving, workplace drug testing, oral fluid analysis, drug-facilitated sexual assault).
Leroy, C; Delbarre-Ladrat, C; Ghillebaert, F; Rochet, M J; Compère, C; Combes, D
2007-04-01
To develop a method to screen antifouling agents against marine bacterial adhesion as a sensitive, rapid and quantitative microplate fluorescent test. Our experimental method is based on a natural biofilm formed by mono-incubation of the marine bacterium Pseudoalteromonas sp. D41 in sterile natural sea water in a 96-well polystyrene microplate. The 4'6-diamidino-2-phenylindole dye was used to quantify adhered bacteria in each well. The total measured fluorescence in the wells was correlated with the amount of bacteria showing a detection limit of one bacterium per 5 microm(2) and quantifying 2 x 10(7) to 2 x 10(8) bacteria adhered per cm(2). The antifouling properties of three commercial surface-active agents and chlorine were tested by this method in the prevention of adhesion and also in the detachment of already adhered bacteria. The marine bacterial adhesion inhibition rate depending on the agent concentration showed a sigmoid shaped dose-response curve. This test is well adapted for a rapid and quantitative first screening of antifouling agents directly in seawater in the early steps of marine biofilm formation. In contrast to the usual screenings of antifouling products which detect a bactericidal activity, this test is more appropriate to screen antifouling agents for bacterial adhesion removal or bacterial adhesion inhibition activities. This screening test focuses on the antifouling properties of the products, especially the initial steps of marine biofilm formation.
Cost-Effectiveness of Three Rounds of Mammography Breast Cancer Screening in Iranian Women
Haghighat, Shahpar; Akbari, Mohammad Esmaeil; Yavari, Parvin; Javanbakht, Mehdi; Ghaffari, Shahram
2016-01-01
Background Breast cancer is the most common cancer in Iranian women as is worldwide. Mammography screening has been introduced as a beneficial method for reducing mortality and morbidity of this disease. Objectives We developed an analytical model to assess the cost effectiveness of an organized mammography screening program in Iran for early detection of the breast cancer. Patients and Methods This study is an economic evaluation of mammography screening program among Iranian woman aged 40 - 70 years. A decision tree and Markov model were applied to estimate total quality adjusted life years (QALY) and lifetime costs. Results The results revealed that the incremental cost effectiveness ratio (ICER) of mammography screening in Iranian women in the first round was Int. $ 37,350 per QALY gained. The model showed that the ICER in the second and third rounds of screening program were Int. $ 141,641 and Int. $ 389,148 respectively. Conclusions Study results identified that mammography screening program was cost-effective in 53% of the cases, but incremental cost per QALY in the second and third rounds of screening are much higher than the accepted payment threshold of Iranian health system. Thus, evaluation of other screening strategies would be useful to identify more cost-effective program. Future studies with new national data can improve the accuracy of our finding and provide better information for health policy makers for decision making. PMID:27366315
High-throughput cocrystal slurry screening by use of in situ Raman microscopy and multi-well plate.
Kojima, Takashi; Tsutsumi, Shunichirou; Yamamoto, Katsuhiko; Ikeda, Yukihiro; Moriwaki, Toshiya
2010-10-31
Cocrystal has attracted much attention in order to improve poor physicochemical properties, since cocrystal former crystallize with the ionic drugs as well as nonionic drugs. Cocrystal screening was usually conducted by crystallization, slurry and co-grinding techniques, however sensitivity, cost and time for screening were limited because of issues such as dissociation of cocrystal during crystallization and cost and time required for slurry and co-grinding methods. To overcome these issues, novel high-throughput cocrystal slurry screening was developed by using in situ Raman microscope and a multi-well plate. Cocrystal screening of indomethacin was conducted with 46 cocrystal formers and potential cocrystals were prepared on a large scale for the characterization with powder X-ray diffractometry, thermal analysis, and Raman microscopy and (1)H NMR spectroscopy. Compared with the characterization of scale-up cocrystals, the cocrystal screening indicated that indomethacin structured novel cocrystals with D/L-mandelic acid, nicotinamide, lactamide and benzamide which was not obtained in the screening with crystallization technique previously reported. In addition, the screening provided not only information of cocrystal formation within a day but also information of equilibrium of cocrystal formation and polymorphic transformation in one screening. Information obtained in this screening allows effective solid form selection by saving cost and time for the development. Copyright © 2010 Elsevier B.V. All rights reserved.
Development of the Stress of Immigration Survey (SOIS): a Field Test among Mexican Immigrant Women
Sternberg, Rosa Maria; Nápoles, Anna Maria; Gregorich, Steven; Paul, Steven; Lee, Kathryn A.; Stewart, Anita L.
2016-01-01
The Stress of Immigration Survey (SOIS) is a screening tool used to assess immigration-related stress. The mixed methods approach included concept development, pretesting, field-testing, and psychometric evaluation in a sample of 131 low-income women of Mexican descent. The 21-item SOIS screens for stress related to language; immigrant status; work issues; yearning for family and home country; and cultural dissonance. Mean scores ranged from 3.6 to 4.4 (1-5 scale, higher is more stress). Cronbach's alphas >.80 for all sub-scales. The SOIS may be a useful screening tool for detecting high levels of immigration-related stress in low-income Mexican immigrant women. PMID:26605954
Badoud, F; Grata, E; Perrenoud, L; Saugy, M; Rudaz, S; Veuthey, J-L
2010-06-18
For doping control, analyses of samples are generally achieved in two steps: a rapid screening and, in the case of a positive result, a confirmatory analysis. A two-step methodology based on ultra-high-pressure liquid chromatography coupled to a quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) was developed to screen and confirm 103 doping agents from various classes (e.g., beta-blockers, stimulants, diuretics, and narcotics). The screening method was presented in a previous article as part I (i.e., Fast analysis of doping agents in urine by ultra-high-pressure liquid chromatography-quadrupole time-of-flight mass spectrometry. Part I: screening analysis). For the confirmatory method, basic, neutral and acidic compounds were extracted by a dedicated solid-phase extraction (SPE) in a 96-well plate format and detected by MS in the tandem mode to obtain precursor and characteristic product ions. The mass accuracy and the elemental composition of precursor and product ions were used for compound identification. After validation including matrix effect determination, the method was considered reliable to confirm suspect results without ambiguity according to the positivity criteria established by the World Anti-Doping Agency (WADA). Moreover, an isocratic method was developed to separate ephedrine from its isomer pseudoephedrine and cathine from phenylpropanolamine in a single run, what allowed their direct quantification in urine. Copyright (c) 2010 Elsevier B.V. All rights reserved.
2013-01-01
Background Many proteins and peptides have been used in therapeutic or industrial applications. They are often produced in microbial production hosts by fermentation. Robust protein production in the hosts and efficient downstream purification are two critical factors that could significantly reduce cost for microbial protein production by fermentation. Producing proteins/peptides as inclusion bodies in the hosts has the potential to achieve both high titers in fermentation and cost-effective downstream purification. Manipulation of the host cells such as overexpression/deletion of certain genes could lead to producing more and/or denser inclusion bodies. However, there are limited screening methods to help to identify beneficial genetic changes rendering more protein production and/or denser inclusion bodies. Results We report development and optimization of a simple density gradient method that can be used for distinguishing and sorting E. coli cells with different buoyant densities. We demonstrate utilization of the method to screen genetic libraries to identify a) expression of glyQS loci on plasmid that increased expression of a peptide of interest as well as the buoyant density of inclusion body producing E. coli cells; and b) deletion of a host gltA gene that increased the buoyant density of the inclusion body produced in the E. coli cells. Conclusion A novel density gradient sorting method was developed to screen genetic libraries. Beneficial host genetic changes could be exploited to improve recombinant protein expression as well as downstream protein purification. PMID:23638724
Pandey, Neeraj; Sachan, Annapurna; Chen, Qi; Ruebling-Jass, Kristin; Bhalla, Ritu; Panguluri, Kiran Kumar; Rouviere, Pierre E; Cheng, Qiong
2013-05-02
Many proteins and peptides have been used in therapeutic or industrial applications. They are often produced in microbial production hosts by fermentation. Robust protein production in the hosts and efficient downstream purification are two critical factors that could significantly reduce cost for microbial protein production by fermentation. Producing proteins/peptides as inclusion bodies in the hosts has the potential to achieve both high titers in fermentation and cost-effective downstream purification. Manipulation of the host cells such as overexpression/deletion of certain genes could lead to producing more and/or denser inclusion bodies. However, there are limited screening methods to help to identify beneficial genetic changes rendering more protein production and/or denser inclusion bodies. We report development and optimization of a simple density gradient method that can be used for distinguishing and sorting E. coli cells with different buoyant densities. We demonstrate utilization of the method to screen genetic libraries to identify a) expression of glyQS loci on plasmid that increased expression of a peptide of interest as well as the buoyant density of inclusion body producing E. coli cells; and b) deletion of a host gltA gene that increased the buoyant density of the inclusion body produced in the E. coli cells. A novel density gradient sorting method was developed to screen genetic libraries. Beneficial host genetic changes could be exploited to improve recombinant protein expression as well as downstream protein purification.
Nordeste, Ricardo F; Trainer, Maria A; Charles, Trevor C
2010-01-01
Development of different PHAs as alternatives to petrochemically derived plastics can be facilitated by mining metagenomic libraries for diverse PHA cycle genes that might be useful for synthesis of bioplastics. The specific phenotypes associated with mutations of the PHA synthesis pathway genes in Sinorhizobium meliloti allows for the use of powerful selection and screening tools to identify complementing novel PHA synthesis genes. Identification of novel genes through their function rather than sequence facilitates finding functional proteins that may otherwise have been excluded through sequence-only screening methodology. We present here methods that we have developed for the isolation of clones expressing novel PHA metabolism genes from metagenomic libraries.
Cheng, Jiujun; Nordeste, Ricardo; Trainer, Maria A; Charles, Trevor C
2017-01-01
Development of different PHAs as alternatives to petrochemically derived plastics can be facilitated by mining metagenomic libraries for diverse PHA cycle genes that might be useful for synthesis of bio-plastics. The specific phenotypes associated with mutations of the PHA synthesis pathway genes in Sinorhizobium meliloti and Pseudomonas putida, allows the use of powerful selection and screening tools to identify complementing novel PHA synthesis genes. Identification of novel genes through their function rather than sequence facilitates the functional proteins that may otherwise have been excluded through sequence-only screening methodology. We present here methods that we have developed for the isolation of clones expressing novel PHA metabolism genes from metagenomic libraries.
Zhou, Jian-Liang; Wu, Ye-Qing; Tan, Chun-Mei; Zhu, Ming; Ma, Lin-Ke
2016-10-01
A target cell extraction-chemical profiling method based on human alveolar adenocarcinoma cell line (A549 cells) and UHPLC/LTQ Orbitrap MS for screening the anti-lung cancer bioactive compounds from Curcuma longa has been developed in this paper. According to the hypothesis that when cells are incubated together with the extract of Curcuma longa, the potential bioactive compounds in the extract should selectively combine with the cells, then the cell-binding compounds could be separated and analyzed by LC-MS. The bioactive compounds in C. longa are lipophilic components. They intend to be absorbed on the inner wall of cell culture flask when they were incubated with A549 cells, which will produce interference in the blank solution. In this paper, by using cells digestion and multi-step centrifugation and transfer strategy, the interference problem has been solved. Finally, using the developed method, three cell-binding compounds were screened out and were identified as bisdemethoxycurcumin, demethoxycurcumin, and curcumin. These compounds are the main bioactive compounds with anti-lung cancer bioactivity in C. longa. The improved method developed in this paper could avoid the false positive results due to the absorption of lipophilic compounds on the inner wall of cell culture flask, which will to be an effective complementary method for current target cell extraction-chemical profiling technology. Copyright© by the Chinese Pharmaceutical Association.
Simple and fast screening of G-quadruplex ligands with electrochemical detection system.
Fan, Qiongxuan; Li, Chao; Tao, Yaqin; Mao, Xiaoxia; Li, Genxi
2016-11-01
Small molecules that may facilitate and stabilize the formation of G-quadruplexes can be used for cancer treatments, because the G-quadruplex structure can inhibit the activity of telomerase, an enzyme over-expressed in many cancer cells. Therefore, there is considerable interest in developing a simple and high-performance method for screening small molecules binding to G-quadruplex. Here, we have designed a simple electrochemical approach to screen such ligands based on the fact that the formation and stabilization of G-quadruplex by ligand may inhibit electron transfer of redox species to electrode surface. As a proof-of-concept study, two types of classical G-quadruplex ligands, TMPyP4 and BRACO-19, are studied in this work, which demonstrates that this method is fast and robust and it may be applied to screen G-quadruplex ligands for anticancer drugs testing and design in the future. Copyright © 2016 Elsevier B.V. All rights reserved.
Shi, Shu Yun; Zhang, Yu Ping; Zhou, Hong Hao; Huang, Ke Long; Jiang, Xin Yu
2010-01-01
An online rapid screening method, the high-performance liquid chromatography (HPLC)-diode array detector (DAD)-radical scavenging detection (RSD)-electrospray ionization (ESI)-mass spectroscopy (MS)/MS system, was developed for the screening and identification of radical scavengers from Neo-Taraxacum siphonanthum, a new species found in China in 1989. For further characterization, the target compounds were isolated by silica column chromatography, preparative high-performance liquid chromatography (HPLC), HSCCC, and Sephadex LH-20 column chromatography and elucidated on the basis of ultraviolet (UV), ESI-MS/MS, and nuclear magnetic resonance (NMR) spectroscopy, as well as the chemical analysis. Eighteen antioxidative polyphenols (5 caffeic acid derivatives and 13 flavonoid derivatives) were characterized from Neo-T. siphonanthum. The distribution of all compounds was discussed in a chemosystematic context, which suggested that the genera Neo-Taraxacum and Taraxacum might relate chemosystematically.
Diving deeper into Zebrafish development of social behavior: analyzing high resolution data.
Buske, Christine; Gerlai, Robert
2014-08-30
Vertebrate model organisms have been utilized in high throughput screening but only with substantial cost and human capital investment. The zebrafish is a vertebrate model species that is a promising and cost effective candidate for efficient high throughput screening. Larval zebrafish have already been successfully employed in this regard (Lessman, 2011), but adult zebrafish also show great promise. High throughput screening requires the use of a large number of subjects and collection of substantial amount of data. Collection of data is only one of the demanding aspects of screening. However, in most screening approaches that involve behavioral data the main bottleneck that slows throughput is the time consuming aspect of analysis of the collected data. Some automated analytical tools do exist, but often they only work for one subject at a time, eliminating the possibility of fully utilizing zebrafish as a screening tool. This is a particularly important limitation for such complex phenotypes as social behavior. Testing multiple fish at a time can reveal complex social interactions but it may also allow the identification of outliers from a group of mutagenized or pharmacologically treated fish. Here, we describe a novel method using a custom software tool developed within our laboratory, which enables tracking multiple fish, in combination with a sophisticated analytical approach for summarizing and analyzing high resolution behavioral data. This paper focuses on the latter, the analytic tool, which we have developed using the R programming language and environment for statistical computing. We argue that combining sophisticated data collection methods with appropriate analytical tools will propel zebrafish into the future of neurobehavioral genetic research. Copyright © 2014. Published by Elsevier B.V.
Application of a Permethrin Immunosorbent Assay Method to Residential Soil and Dust Samples
A low-cost, high throughput bioanalytical screening method was developed for monitoring cis/trans-permethrin in dust and soil samples. The method consisted of a simple sample preparation procedure [sonication with dichloromethane followed by a solvent exchange into methanol:wate...
NASA Astrophysics Data System (ADS)
Yamada, Takayuki; Gohshi, Seiichi; Echizen, Isao
A method is described to prevent video images and videos displayed on screens from being re-shot by digital cameras and camcorders. Conventional methods using digital watermarking for re-shooting prevention embed content IDs into images and videos, and they help to identify the place and time where the actual content was shot. However, these methods do not actually prevent digital content from being re-shot by camcorders. We developed countermeasures to stop re-shooting by exploiting the differences between the sensory characteristics of humans and devices. The countermeasures require no additional functions to use-side devices. It uses infrared light (IR) to corrupt the content recorded by CCD or CMOS devices. In this way, re-shot content will be unusable. To validate the method, we developed a prototype system and implemented it on a 100-inch cinema screen. Experimental evaluations showed that the method effectively prevents re-shooting.
THE VIEW FROM THE TRENCHES: PART 2–TECHNICAL CONSIDERATIONS FOR EPR SCREENING
Nicolalde, Roberto J.; Gougelet, Robert M.; Rea, Michael; Williams, Benjamin B.; Dong, Ruhong; Kmiec, Maciej M.; Lesniewski, Piotr N.; Swartz, Harold M.
2014-01-01
There is growing awareness of the need for methodologies that can be used retrospectively to provide the biodosimetry needed to carry out screening and triage immediately after an event in which large numbers of people have potentially received clinically significant doses of ionizing radiation. The general approach to developing such methodologies has been a technology centric one, often ignoring the system integrations considerations that are key to their effective use. In this study an integrative approach for the evaluation and development of a physical biodosimetry technology was applied based on in vivo electron paramagnetic resonance (EPR) dosimetry. The EPR measurements are based on physical changes in tissues whose magnitudes are not affected by the factors that can confound biologically-based assessments. In this study the use of a pilot simulation exercise to evaluate an experimental EPR system and gather stakeholders’ feedback early on in the development process is described. The exercise involved: ten non-irradiated participants, representatives from a local fire department; Department of Homeland Security certified exercise evaluators, EPR experts, physicians; and a human factors engineer. Stakeholders were in agreement that the EPR technology in its current state of development could be deployed for the screening of mass casualties. Furthermore, stakeholders’ recommendations will be prioritized and incorporated in future developments of the EPR technique. While the results of this exercise were aimed specifically at providing feedback for the development of EPR dosimetry for screening mass casualties, the methods and lessons learned are likely to be applicable to other biodosimetric methods. PMID:20065674
Digital mammography, cancer screening: Factors important for image compression
NASA Technical Reports Server (NTRS)
Clarke, Laurence P.; Blaine, G. James; Doi, Kunio; Yaffe, Martin J.; Shtern, Faina; Brown, G. Stephen; Winfield, Daniel L.; Kallergi, Maria
1993-01-01
The use of digital mammography for breast cancer screening poses several novel problems such as development of digital sensors, computer assisted diagnosis (CAD) methods for image noise suppression, enhancement, and pattern recognition, compression algorithms for image storage, transmission, and remote diagnosis. X-ray digital mammography using novel direct digital detection schemes or film digitizers results in large data sets and, therefore, image compression methods will play a significant role in the image processing and analysis by CAD techniques. In view of the extensive compression required, the relative merit of 'virtually lossless' versus lossy methods should be determined. A brief overview is presented here of the developments of digital sensors, CAD, and compression methods currently proposed and tested for mammography. The objective of the NCI/NASA Working Group on Digital Mammography is to stimulate the interest of the image processing and compression scientific community for this medical application and identify possible dual use technologies within the NASA centers.
Gwede, Clement K.; Davis, Stacy N.; Wilson, Shaenelle; Patel, Mitul; Vadaparampil, Susan T.; Meade, Cathy D.; Rivers, Brian M.; Yu, Daohai; Torres-Roca, Javier; Heysek, Randy; Spiess, Philippe E.; Pow-Sang, Julio; Jacobsen, Paul
2014-01-01
Purpose First-degree relatives (FDRs) of prostate cancer (PC) patients should consider multiple concurrent personal risk factors when engaging in informed decision making (IDM) about PC screening. This study assessed perceptions of IDM recommendations and risk-appropriate strategies for IDM among FDRs of varied race/ethnicity. Design A cross-sectional, qualitative Setting Study setting was a cancer center in southwest Florida. Participants The study comprised 44 participants (24 PC patients and 20 unaffected FDRs). Method Focus groups and individual interviews were conducted and analyzed using content analysis and constant comparison methods. Results Patients and FDRs found the PC screening debate and IDM recommendations to be complex and counterintuitive. They overwhelmingly believed screening saves lives and does not have associated harms. There was a strongly expressed need to improve communication between patients and FDRs. A single decision aid that addresses the needs of all FDRs, rather than separating by race/ethnicity, was recommended as sufficient by study participants. These perspectives guided the development of an innovative decision aid that deconstructs the screening controversy and IDM processes into simpler concepts and provides step-by-step strategies for FDRs to engage in IDM. Conclusion Implementing IDM among FDRs is challenging because the IDM paradigm departs from historical messages promoting routine screening. These contradictions should be recognized and addressed for men to participate effectively in IDM. A randomized pilot study evaluating outcomes of the resulting decision aid is underway. PMID:24968183
Large-scale mapping of mutations affecting zebrafish development.
Geisler, Robert; Rauch, Gerd-Jörg; Geiger-Rudolph, Silke; Albrecht, Andrea; van Bebber, Frauke; Berger, Andrea; Busch-Nentwich, Elisabeth; Dahm, Ralf; Dekens, Marcus P S; Dooley, Christopher; Elli, Alexandra F; Gehring, Ines; Geiger, Horst; Geisler, Maria; Glaser, Stefanie; Holley, Scott; Huber, Matthias; Kerr, Andy; Kirn, Anette; Knirsch, Martina; Konantz, Martina; Küchler, Axel M; Maderspacher, Florian; Neuhauss, Stephan C; Nicolson, Teresa; Ober, Elke A; Praeg, Elke; Ray, Russell; Rentzsch, Brit; Rick, Jens M; Rief, Eva; Schauerte, Heike E; Schepp, Carsten P; Schönberger, Ulrike; Schonthaler, Helia B; Seiler, Christoph; Sidi, Samuel; Söllner, Christian; Wehner, Anja; Weiler, Christian; Nüsslein-Volhard, Christiane
2007-01-09
Large-scale mutagenesis screens in the zebrafish employing the mutagen ENU have isolated several hundred mutant loci that represent putative developmental control genes. In order to realize the potential of such screens, systematic genetic mapping of the mutations is necessary. Here we report on a large-scale effort to map the mutations generated in mutagenesis screening at the Max Planck Institute for Developmental Biology by genome scanning with microsatellite markers. We have selected a set of microsatellite markers and developed methods and scoring criteria suitable for efficient, high-throughput genome scanning. We have used these methods to successfully obtain a rough map position for 319 mutant loci from the Tübingen I mutagenesis screen and subsequent screening of the mutant collection. For 277 of these the corresponding gene is not yet identified. Mapping was successful for 80 % of the tested loci. By comparing 21 mutation and gene positions of cloned mutations we have validated the correctness of our linkage group assignments and estimated the standard error of our map positions to be approximately 6 cM. By obtaining rough map positions for over 300 zebrafish loci with developmental phenotypes, we have generated a dataset that will be useful not only for cloning of the affected genes, but also to suggest allelism of mutations with similar phenotypes that will be identified in future screens. Furthermore this work validates the usefulness of our methodology for rapid, systematic and inexpensive microsatellite mapping of zebrafish mutations.
Fathima, Mariam; Naik-Panvelkar, Pradnya; Saini, Bandana; Armour, Carol L.
Objective The purpose of this review was to evaluate the role of community pharmacists in provision of screening with/without subsequent management of undiagnosed chronic obstructive pulmonary disease (COPD) and uncontrolled asthma. Methods An extensive literature search using four databases (ie. Medline, PubMed, International Pharmaceutical Abstracts (IPA) and Scopus) with search terms pharmacy, screening, asthma or COPD was conducted. Searches were limited to the years 2003-2013, those in English and those reporting research with humans. Data retrieval, analysis and result presentation employed a scoping review method. Results Seventeen articles met the inclusion/exclusion criteria, of which fifteen studies were based on people with asthma and two were based on people with COPD. Only seven asthma studies and one COPD study involved screening followed by subsequent management. More than half of the people screened were found to be poorly controlled and up to 62% of people were identified at high risk for COPD by community pharmacists. The studies varied in the method and type of asthma control assessment/screening, the type of intervention provided and the outcomes measured. The limitations of the reviewed studies included varying definitions of asthma control, different study methodologies, and the lack of long-term follow-up. While many different methods were used for risk assessment and management services by the pharmacists, all the studies demonstrated that community pharmacists were capable of identifying people with poorly controlled asthma and undiagnosed COPD and providing them with suitable interventions. Conclusions The literature review identified that community pharmacists can play an effective role in screening of people with poorly controlled asthma and undiagnosed COPD along with delivering management interventions. However, there is very little literature available on screening for these chronic respiratory conditions. Future research should focus on development of patient care delivery model incorporating a screening protocol followed by targeted management interventions delivered by the community pharmacist. PMID:24367463
Methods for Evaluating Mammography Imaging Techniques
1999-06-01
Distribution Unlimited 12b. DIS5TRIBUTION CODE 13. ABSTRACT (Maximum 200 words) This Department of Defense Breast Cancer Research Program Career...Development Award is enabling Dr. Rütter to develop bio’statistical methods for breast cancer research. Dr. Rutter is focusing on methods for...evaluating the accuracy of breast cancer screening. This four year program includes advanced training in the epidemiology of breast cancer , training in
Lee, Hyun; Mittal, Anuradha; Patel, Kavankumar; Gatuz, Joseph L; Truong, Lena; Torres, Jaime; Mulhearn, Debbie C; Johnson, Michael E
2014-01-01
We have used a combination of virtual screening (VS) and high-throughput screening (HTS) techniques to identify novel, non-peptidic small molecule inhibitors against human SARS-CoV 3CLpro. A structure-based VS approach integrating docking and pharmacophore based methods was employed to computationally screen 621,000 compounds from the ZINC library. The screening protocol was validated using known 3CLpro inhibitors and was optimized for speed, improved selectivity, and for accommodating receptor flexibility. Subsequently, a fluorescence-based enzymatic HTS assay was developed and optimized to experimentally screen approximately 41,000 compounds from four structurally diverse libraries chosen mainly based on the VS results. False positives from initial HTS hits were eliminated by a secondary orthogonal binding analysis using surface plasmon resonance (SPR). The campaign identified a reversible small molecule inhibitor exhibiting mixed-type inhibition with a K(i) value of 11.1 μM. Together, these results validate our protocols as suitable approaches to screen virtual and chemical libraries, and the newly identified compound reported in our study represents a promising structural scaffold to pursue for further SARS-CoV 3CLpro inhibitor development. Copyright © 2013. Published by Elsevier Ltd.
Using handgrip strength to screen for diabetes in developing countries.
Eckman, Molly; Gigliotti, Christopher; Sutermaster, Staci; Butler, Peter J; Mehta, Khanjan
2016-01-01
Lack of access to healthcare in the developing world has created a need for locally-based primary and pre-primary healthcare systems. Many regions of the world have adopted Community Health Worker (CHW) programmes, but volunteers in these programmes lack the tools and resources to screen for disease. Because of its simplicity of operation, handgrip strength (HGS) measurements have the potential to be an affordable and effective screening tool for conditions that cause muscle weakness in this context. In the study described in this report, translators were used to collect data on age, gender, height, weight, blood pressure, HGS and key demographic data. HGS was significantly lower for diabetics than patients without diabetes. A simple binary logistic model was created that used HGS, age, blood pressure and BMI to predict a patient's probability of having diabetes. This study develops a predictive model for diabetes using HGS and other basic health measurements and shows that HGS-based screening is a viable method of early detection of diabetes.
A deep learning and novelty detection framework for rapid phenotyping in high-content screening
Sommer, Christoph; Hoefler, Rudolf; Samwer, Matthias; Gerlich, Daniel W.
2017-01-01
Supervised machine learning is a powerful and widely used method for analyzing high-content screening data. Despite its accuracy, efficiency, and versatility, supervised machine learning has drawbacks, most notably its dependence on a priori knowledge of expected phenotypes and time-consuming classifier training. We provide a solution to these limitations with CellCognition Explorer, a generic novelty detection and deep learning framework. Application to several large-scale screening data sets on nuclear and mitotic cell morphologies demonstrates that CellCognition Explorer enables discovery of rare phenotypes without user training, which has broad implications for improved assay development in high-content screening. PMID:28954863
High Throughput Screening for Inhibitors of Mycobacterium tuberculosis H37Rv
ANANTHAN, SUBRAMANIAM; FAALEOLEA, ELLEN R.; GOLDMAN, ROBERT C.; HOBRATH, JUDITH V.; KWONG, CECIL D.; LAUGHON, BARBARA E.; MADDRY, JOSEPH A.; MEHTA, ALKA; RASMUSSEN, LYNN; REYNOLDS, ROBERT C.; SECRIST, JOHN A.; SHINDO, NICE; SHOWE, DUSTIN N.; SOSA, MELINDA I.; SULING, WILLIAM J.; WHITE, E. LUCILE
2009-01-01
SUMMARY There is an urgent need for the discovery and development of new antitubercular agents that target new biochemical pathways and treat drug resistant forms of the disease. One approach to addressing this need is through high throughput screening of medicinally relevant libraries against the whole bacterium in order to discover a variety of new, active scaffolds that will stimulate new biological research and drug discovery. Through the Tuberculosis Antimicrobial Acquisition and Coordinating Facility (www.taacf.org), a large, medicinally relevant chemical library was screened against M. tuberculosis strain H37Rv. The screening methods and a medicinal chemistry analysis of the results are reported herein. PMID:19758845
Virtual screening of compound libraries.
Cerqueira, Nuno M F S A; Sousa, Sérgio F; Fernandes, Pedro A; Ramos, Maria João
2009-01-01
During the last decade, Virtual Screening (VS) has definitively established itself as an important part of the drug discovery and development process. VS involves the selection of likely drug candidates from large libraries of chemical structures by using computational methodologies, but the generic definition of VS encompasses many different methodologies. This chapter provides an introduction to the field by reviewing a variety of important aspects, including the different types of virtual screening methods, and the several steps required for a successful virtual screening campaign within a state-of-the-art approach, from target selection to postfilter application. This analysis is further complemented with a small collection important VS success stories.
A mix-and-read drop-based in vitro two-hybrid method for screening high-affinity peptide binders
Cui, Naiwen; Zhang, Huidan; Schneider, Nils; Tao, Ye; Asahara, Haruichi; Sun, Zhiyi; Cai, Yamei; Koehler, Stephan A.; de Greef, Tom F. A.; Abbaspourrad, Alireza; Weitz, David A.; Chong, Shaorong
2016-01-01
Drop-based microfluidics have recently become a novel tool by providing a stable linkage between phenotype and genotype for high throughput screening. However, use of drop-based microfluidics for screening high-affinity peptide binders has not been demonstrated due to the lack of a sensitive functional assay that can detect single DNA molecules in drops. To address this sensitivity issue, we introduced in vitro two-hybrid system (IVT2H) into microfluidic drops and developed a streamlined mix-and-read drop-IVT2H method to screen a random DNA library. Drop-IVT2H was based on the correlation between the binding affinity of two interacting protein domains and transcriptional activation of a fluorescent reporter. A DNA library encoding potential peptide binders was encapsulated with IVT2H such that single DNA molecules were distributed in individual drops. We validated drop-IVT2H by screening a three-random-residue library derived from a high-affinity MDM2 inhibitor PMI. The current drop-IVT2H platform is ideally suited for affinity screening of small-to-medium-sized libraries (103–106). It can obtain hits within a single day while consuming minimal amounts of reagents. Drop-IVT2H simplifies and accelerates the drop-based microfluidics workflow for screening random DNA libraries, and represents a novel alternative method for protein engineering and in vitro directed protein evolution. PMID:26940078
A Decision-Tree Approach to Cost Comparison of Newborn Screening Strategies for Cystic Fibrosis
Wells, Janelle; Rosenberg, Marjorie; Hoffman, Gary; Anstead, Michael
2012-01-01
OBJECTIVE: Because cystic fibrosis can be difficult to diagnose and treat early, newborn screening programs have rapidly developed nationwide but methods vary widely. We therefore investigated the costs and consequences or specific outcomes of the 2 most commonly used methods. METHODS: With available data on screening and follow-up, we used a simulation approach with decision trees to compare immunoreactive trypsinogen (IRT) screening followed by a second IRT test against an IRT/DNA analysis. By using a Monte Carlo simulation program, variation in the model parameters for counts at various nodes of the decision trees, as well as for costs, are included and applied to fictional cohorts of 100 000 newborns. The outcome measures included the numbers of newborns given a diagnosis of cystic fibrosis and costs of screening strategy at each branch and cost per newborn. RESULTS: Simulations revealed a substantial number of potential missed diagnoses for the IRT/IRT system versus IRT/DNA. Although the IRT/IRT strategy with commonly used cutoff values offers an average overall cost savings of $2.30 per newborn, a breakdown of costs by societal segments demonstrated higher out-of-pocket costs for families. Two potential system failures causing delayed diagnoses were identified relating to the screening protocols and the follow-up system. CONCLUSIONS: The IRT/IRT screening algorithm reduces the costs to laboratories and insurance companies but has more system failures. IRT/DNA offers other advantages, including fewer delayed diagnoses and lower out-of-pocket costs to families. PMID:22291119
Role of re-screening of cervical smears in internal quality control.
Baker, A; Melcher, D; Smith, R
1995-01-01
AIMS--To investigate the use of rapid re-screening as a quality control method for previously screened cervical slides; to compare this method with 10% random re-screening and clinically indicated double screening. METHODS--Between June 1990 and December 1994, 117,890 negative smears were subjected to rapid re-screening. RESULTS--This study shows that rapid re-screening detects far greater numbers of false negative cases when compared with both 10% random re-screening and clinically indicated double screening, with no additional demand on human resources. The technique also identifies variation in the performance of screening personnel as an additional benefit. CONCLUSION--Rapid re-screening is an effective method of quality control. Although less sensitive, rapid re-screening should replace 10% random re-screening and selected re-screening as greater numbers of false negative results are detected while consuming less resources. PMID:8543619
Mauritzson, L; Ilver, J; Benoni, G; Lindström, K; Willner, S
1991-01-01
Diagnostic ultrasound is an established, noninvasive and harmless method for imaging the shape and appearance of organs and other tissues inside the body, and it has been used in many clinical applications for more than three decades. We have now applied some of this well-known technique together with the use of airborne ultrasound in medical applications, to build an equipment for anthropometrical investigation outside the body, e.g., measuring and registration of the shape and form of the human back. This is mostly done for screening purposes of young people in an attempt to find patients developing scoliosis, and in order to circumvent some of the disadvantages with the traditional screening method in this field of medical application.
Determination of a steroid profile in heel prick blood using LC-MS/MS.
Boelen, Anita; Ruiter, An F C; Claahsen-van der Grinten, Hedi L; Endert, Erik; Ackermans, Mariette T
2016-01-01
The aim of this study was to improve the sensitivity of the congenital adrenal hyperplasia (CAH) neonatal screening by including second-tier steroid profiling on a DBS using LC-MS. We developed a method to measure the steroid profile in DBS and established gestational age-specific reference ranges of cortisol, cortisone, 11-deoxycortisol, 21-deoxycortisol, 17-hydroxyprogesterone, testosterone, Δ4-androstenedione, corticosterone and 11-deoxycorticosterone using 450 heel prick samples of neonates, participating in the Dutch Screening Program. Analyzing 92 cards with a positive CAH screening showed that only 21-deoxycortisol was 100% specific for diagnosed CAH patients. Steroid precursors can be measured in DBS and we suggest to implement the method as a second tier testing for CAH in The Netherlands.
Dittmar, John C.; Pierce, Steven; Rothstein, Rodney; Reid, Robert J. D.
2013-01-01
Genome-wide experiments often measure quantitative differences between treated and untreated cells to identify affected strains. For these studies, statistical models are typically used to determine significance cutoffs. We developed a method termed “CLIK” (Cutoff Linked to Interaction Knowledge) that overlays biological knowledge from the interactome on screen results to derive a cutoff. The method takes advantage of the fact that groups of functionally related interacting genes often respond similarly to experimental conditions and, thus, cluster in a ranked list of screen results. We applied CLIK analysis to five screens of the yeast gene disruption library and found that it defined a significance cutoff that differed from traditional statistics. Importantly, verification experiments revealed that the CLIK cutoff correlated with the position in the rank order where the rate of true positives drops off significantly. In addition, the gene sets defined by CLIK analysis often provide further biological perspectives. For example, applying CLIK analysis retrospectively to a screen for cisplatin sensitivity allowed us to identify the importance of the Hrq1 helicase in DNA crosslink repair. Furthermore, we demonstrate the utility of CLIK to determine optimal treatment conditions by analyzing genome-wide screens at multiple rapamycin concentrations. We show that CLIK is an extremely useful tool for evaluating screen quality, determining screen cutoffs, and comparing results between screens. Furthermore, because CLIK uses previously annotated interaction data to determine biologically informed cutoffs, it provides additional insights into screen results, which supplement traditional statistical approaches. PMID:23589890
Lu, Mei; Chan, Brian M; Schow, Peter W; Chang, Wesley S; King, Chadwick T
2017-12-01
With current available assay formats using either immobilized protein (ELISA, enzyme-linked immunosorbent assay) or immunostaining of fixed cells for primary monoclonal antibody (mAb) screening, researchers often fail to identify and characterize antibodies that recognize the native conformation of cell-surface antigens. Therefore, screening using live cells has become an integral and important step contributing to the successful identification of therapeutic antibody candidates. Thus the need for developing high-throughput screening (HTS) technologies using live cells has become a major priority for therapeutic mAb discovery and development. We have developed a novel technique called Multiplexed Fluorescent Cell Barcoding (MFCB), a flow cytometry-based method based upon the Fluorescent Cell Barcoding (FCB) technique and the Luminex fluorescent bead array system, but is applicable to high-through mAb screens on live cells. Using this technique in our system, we can simultaneously identify or characterize the antibody-antigen binding of up to nine unique fluorescent labeled cell populations in the time that it would normally take to process a single population. This has significantly reduced the amount of time needed for the identification of potential lead candidates. This new technology enables investigators to conduct large-scale primary hybridoma screens using flow cytometry. This in turn has allowed us to screen antibodies more efficiently than before and streamline identification and characterization of lead molecules. Copyright © 2017 Elsevier B.V. All rights reserved.
Quality assurance manual of endoscopic screening for gastric cancer in Japanese communities.
Hamashima, Chisato; Fukao, Akira
2016-09-02
The Japanese government introduced endoscopic screening for gastric cancer in 2015 as a public policy based on the Japanese guidelines on gastric cancer screening. To provide appropriate endoscopic screening for gastric cancer in Japanese communities, we developed a quality assurance manual of endoscopic screening and recommend 10 strategies with their brief descriptions as follows: (i) Formulation of a committee responsible for implementing and managing endoscopic screening, and for deciding the suitable implementation methods in consideration of the local context; (ii) Development of an interpretation system that leads to a final judgement to standardize endoscopic examination and improve its accuracy; (iii) Preparation of management and reporting systems for adverse effects by the committee for safety management; (iv) Obtaining informed consent before operation following adequate explanations regarding the benefits and harms of endoscopic screening; (v) Avoidance of frequent screenings to reduce false-positive results and overdiagnosis. As a reference, the target age group is ≥50 years, and the screening interval is 2 years; (vi) Keeping the biopsy rate within 10% as post-biopsy bleeding may occur. Before endoscopic screening, any history of antithrombotic drug usage should be checked; (vii) Nonadministration of sedation in endoscopic screening for safety management; (viii) Adherence to proper endoscopic cleaning and disinfection to reduce infection; (ix) Use of a checklist to achieve optimal program preparation when municipal governments introduce endoscopic screening; (x) Identification of the aims and roles by referring to a checklist if primary care physicians decide to participate in endoscopic screening. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Dinon, Andréia Z; Prins, Theo W; van Dijk, Jeroen P; Arisi, Ana Carolina M; Scholtens, Ingrid M J; Kok, Esther J
2011-05-01
Primers and probes were developed for the element-specific detection of cry1A.105 and cry2Ab2 genes, based on their DNA sequence as present in GM maize MON89034. Cry genes are present in many genetically modified (GM) plants and they are important targets for developing GMO element-specific detection methods. Element-specific methods can be of use to screen for the presence of GMOs in food and feed supply chains. Moreover, a combination of GMO elements may indicate the potential presence of unapproved GMOs (UGMs). Primer-probe combinations were evaluated in terms of specificity, efficiency and limit of detection. Except for specificity, the complete experiment was performed in 9 PCR runs, on 9 different days and by testing 8 DNA concentrations. The results showed a high specificity and efficiency for cry1A.105 and cry2Ab2 detection. The limit of detection was between 0.05 and 0.01 ng DNA per PCR reaction for both assays. These data confirm the applicability of these new primer-probe combinations for element detection that can contribute to the screening for GM and UGM crops in food and feed samples.
Alfaro, Karla M; Gage, Julia C; Rosenbaum, Alan J; Ditzian, Lauren R; Maza, Mauricio; Scarinci, Isabel C; Miranda, Esmeralda; Villalta, Sofia; Felix, Juan C; Castle, Philip E; Cremer, Miriam L
2015-10-16
Cervical cancer is the third most commonly occurring cancer among women and the fourth leading cause of cancer-related deaths in women worldwide, with more than 85 % of these cases occurring in developing countries. These global disparities reflect the differences in cervical cancer screening rates between high-income and medium- and low-income countries. At 19 %, El Salvador has the lowest reported screening coverage of all Latin American countries. The purpose of this study is to identify factors affecting public sector HPV DNA-based cervical cancer screening participation in El Salvador. This study was nested within a public sector screening program where health promoters used door-to-door outreach to recruit women aged 30-49 years to attend educational sessions about HPV screening. A subgroup of these participants was chosen randomly and questioned about demographic factors, healthcare utilization, previous cervical cancer screening, and HPV knowledge. Women then scheduled screening appointments at their public health clinics. Screening participants were adherent if they attended their scheduled appointment or rescheduled and were screened within 6 months. The association between non-adherence and demographic variables, medical history, history of cancer, sexual history, birth control methods, and screening barriers was assessed using Chi-square tests of significance and logistic regression. All women (n = 409) enrolled in the study scheduled HPV screening appointments, and 88 % attended. Non-adherence was associated with a higher number of lifetime partners and being under-screened-defined as not having participated in cervical cancer screening within the previous 3 years (p = 0.03 and p = 0.04, respectively); 22.8 % of participants in this study were under-screened. Adherence to cervical cancer screening after educational sessions was higher than expected, in part due to interactions with the community-based health promoters as well as the educational session itself. More effective recruitment methods targeted toward under-screened women are required.
Smith, Alec S.T.; Macadangdang, Jesse; Leung, Winnie; Laflamme, Michael A.; Kim, Deok-Ho
2016-01-01
Improved methodologies for modeling cardiac disease phenotypes and accurately screening the efficacy and toxicity of potential therapeutic compounds are actively being sought to advance drug development and improve disease modeling capabilities. To that end, much recent effort has been devoted to the development of novel engineered biomimetic cardiac tissue platforms that accurately recapitulate the structure and function of the human myocardium. Within the field of cardiac engineering, induced pluripotent stem cells (iPSCs) are an exciting tool that offer the potential to advance the current state of the art, as they are derived from somatic cells, enabling the development of personalized medical strategies and patient specific disease models. Here we review different aspects of iPSC-based cardiac engineering technologies. We highlight methods for producing iPSC-derived cardiomyocytes (iPSC-CMs) and discuss their application to compound efficacy/toxicity screening and in vitro modeling of prevalent cardiac diseases. Special attention is paid to the application of micro- and nano-engineering techniques for the development of novel iPSC-CM based platforms and their potential to advance current preclinical screening modalities. PMID:28007615
de Jager, L S; Andrews, A R
2000-11-01
A novel, fast screening method for organochlorine pesticides (OCPs) in water samples has been developed. Total analysis time was less than 9 min, allowing 11 samples to be screened per hour. The relatively new technique of solvent microextraction (SME) was used to extract and preconcentrate the pesticides into a single drop of hexane. The use of a conventional carbon dioxide cryotrap was investigated for introduction of the extract onto a micro-bore (0.1 mm) capillary column for fast GC analysis. A pulsed-discharge electron capture detector was used which yielded selective and sensitive measurement of the pesticide peaks. Fast GC conditions were optimised and tested with the previously developed SME procedure. Calibration curves yielded good linearity and concentrations down to 0.25 ng mL-1 were detectable with RSD values ranging from 12.0 to 28% and LOD for most OCPs at 0.25 ng mL-1. Spiked river water samples were tested and using the developed screen we were able to differentiate between spiked samples and samples containing no OCPs.
Liu, Chao-Li; Hackley, Keith C.; Coleman, D.D.; Kruse, C.W.
1987-01-01
A method using stable isotope ratio analysis to monitor the reactivity of sulfur forms in coal during thermal and chemical desulfurization processes has been developed at the Illinois State Geological Survey. The method is based upon the fact that a significant difference exists in some coals between the 34S/32S ratios of the pyritic and organic sulfur. A screening method for determining the suitability of coal samples for use in isotope ratio analysis is described. Making these special coals available from coal sample programs would assist research groups in sorting out the complex sulfur chemistry which accompanies thermal and chemical processing of high sulfur coals. ?? 1987.
Convenient, sensitive and high-throughput method for screening botanic origin.
Yuan, Yuan; Jiang, Chao; Liu, Libing; Yu, Shulin; Cui, Zhanhu; Chen, Min; Lin, Shufang; Wang, Shu; Huang, Luqi
2014-06-23
In this work, a rapid (within 4-5 h), sensitive and visible new method for assessing botanic origin is developed by combining loop-mediated isothermal amplification with cationic conjugated polymers. The two Chinese medicinal materials (Jin-Yin-Hua and Shan-Yin-Hua) with similar morphology and chemical composition were clearly distinguished by gene SNP genotyping assays. The identification of plant species in Patented Chinese drugs containing Lonicera buds is successfully performed using this detection system. The method is also robust enough to be used in high-throughput screening. This new method is very helpful to identify herbal materials, and is beneficial for detecting safety and quality of botanic products.
De Abreu, Chantelle; Horsfall, Hannah
2013-01-01
Abstract Background In South Africa cervical cancer is the second most commonly occurring cancer amongst women, and black African women have the highest risk of developing this disease. Unfortunately, the majority of South African women do not adhere to recommended regular cervical screening. Objectives The purpose of this research was to explore the perceptions, experiences and knowledge regarding cervical screening of disadvantaged women in two informal settlements in South African urban areas. Method The Health Belief Model (HBM) provided a theoretical framework for this study. Four focus groups (n = 21) were conducted, using questions derived from the HBM, and thematic analysis was used to analyse the data. The ages of the women who participated ranged from 21 to 53 years. Results The analysis revealed lack of knowledge about screening as a key structural barrier to treatment. Other structural barriers were: time, age at which free screening is available, and health education. The psychosocial barriers that were identified included: fear of the screening procedure and of the stigmatisation in attending screening. The presence of physical symptoms, the perception that screening provides symptom relief, HIV status, and the desire to know one's physical health status were identified as facilitators of cervical screening adherence. Conclusion This knowledge has the potential to inform healthcare policy and services in South Africa. As globalisation persists and individuals continue to immigrate or seek refugee status in foreign countries, increased understanding and knowledge is required for successful acculturation and integration. Developed countries may therefore also benefit from research findings in developing countries.
A simple, fast and sensitive screening LC-ESI-MS/MS method for antibiotics in fish.
Guidi, Letícia Rocha; Santos, Flávio Alves; Ribeiro, Ana Cláudia S R; Fernandes, Christian; Silva, Luiza H M; Gloria, Maria Beatriz A
2017-01-15
The objective of this study was to develop and validate a fast, sensitive and simple liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) method for the screening of six classes of antibiotics (aminoglycosides, beta-lactams, macrolides, quinolones, sulfonamides and tetracyclines) in fish. Samples were extracted with trichloroacetic acid. LC separation was achieved on a Zorbax Eclipse XDB C18 column and gradient elution using 0.1% heptafluorobutyric acid in water and acetonitrile as mobile phase. Analysis was carried out in multiple reaction monitoring mode via electrospray interface operated in the positive ionization mode, with sulfaphenazole as internal standard. The method was suitable for routine screening purposes of 40 antibiotics, according to EC Guidelines for the Validation of Screening Methods for Residues of Veterinary Medicines, taking into consideration threshold value, cut-off factor, detection capability, limit of detection, sensitivity and specificity. Real fish samples (n=193) from aquaculture were analyzed and 15% were positive for enrofloxacin (quinolone), one of them at a higher concentration than the level of interest (50µgkg -1 ), suggesting possible contamination or illegal use of that antibiotic. Copyright © 2016 Elsevier B.V. All rights reserved.
USDA-ARS?s Scientific Manuscript database
A sample preparation method was developed for the screening of deoxynivalenol (DON) in wheat and wheat dust. Extraction was carried out with water and was successful due to the polar character of DON. For detection, an enzyme-linked immunosorbent assay (ELISA) was compared to the sensor-based techni...
Pasin, Daniel; Cawley, Adam; Bidny, Sergei; Fu, Shanlin
2017-10-01
The proliferation of new psychoactive substances (NPS) in recent years has resulted in the development of numerous analytical methods for the detection and identification of known and unknown NPS derivatives. High-resolution mass spectrometry (HRMS) has been identified as the method of choice for broad screening of NPS in a wide range of analytical contexts because of its ability to measure accurate masses using data-independent acquisition (DIA) techniques. Additionally, it has shown promise for non-targeted screening strategies that have been developed in order to detect and identify novel analogues without the need for certified reference materials (CRMs) or comprehensive mass spectral libraries. This paper reviews the applications of HRMS for the analysis of NPS in forensic drug chemistry and analytical toxicology. It provides an overview of the sample preparation procedures in addition to data acquisition, instrumental analysis, and data processing techniques. Furthermore, it gives an overview of the current state of non-targeted screening strategies with discussion on future directions and perspectives of this technique. Graphical Abstract Missing the bullseye - a graphical respresentation of non-targeted screening. Image courtesy of Christian Alonzo.
Batista, Fernanda Aparecida Heleno
2018-01-01
Peroxisome proliferator-activated receptor beta/delta (PPARß/δ) is considered a therapeutic target for metabolic disorders, cancer, and cardiovascular diseases. Here, we developed one pipeline for the screening of PPARß/δ agonists, which reduces the cost, time, and false-positive hits. The first step is an optimized 3-day long cellular transactivation assay based on reporter-gene technology, which is supported by automated liquid-handlers. This primary screening is followed by a confirmatory transactivation assay and by two biophysical validation methods (thermal shift assay (TSA) and (ANS) fluorescence quenching), which allow the calculation of the affinity constant, giving more information about the selected hits. All of the assays were validated using well-known commercial agonists providing trustworthy data. Furthermore, to validate and test this pipeline, we screened a natural extract library (560 extracts), and we found one plant extract that might be interesting for PPARß/δ modulation. In conclusion, our results suggested that we developed a cheaper and more robust pipeline that goes beyond the single activation screening, as it also evaluates PPARß/δ tertiary structure stabilization and the ligand affinity constant, selecting only molecules that directly bind to the receptor. Moreover, this approach might improve the effectiveness of the screening for agonists that target PPARß/δ for drug development.
Lee, Hee Yun; Koopmeiners, Joseph S; Rhee, Taeho Greg; Raveis, Victoria H; Ahluwalia, Jasjit S
2014-08-27
Cervical cancer poses a significant threat to Korean American women, who are reported to have one of the highest cervical cancer mortality rates in the United States. Studies consistently report that Korean American women have the lowest Pap test screening rates across US ethnic groups. In response to the need to enhance cervical cancer screening in this vulnerable population, we developed and tested a 7-day mobile phone text message-based cervical cancer Screening (mScreening) intervention designed to promote the receipt of Pap tests by young Korean American women. We developed and assessed the acceptability and feasibility of a 1-week mScreening intervention to increase knowledge of cervical cancer screening, intent to receive screening, and the receipt of a Pap test. Fogg's Behavior Model was the conceptual framework that guided the development of the mScreening intervention. A series of focus groups were conducted to inform the development of the intervention. The messages were individually tailored for each participant and delivered to them for a 7-day period at each participant's preferred time. A quasi-experimental research design of 30 Korean American women aged 21 to 29 years was utilized with baseline, post (1 week after the completion of mScreening), and follow-up (3 months after the completion of mScreening) testing. Findings revealed a significant increase in participants' knowledge of cervical cancer (P<.001) and guidelines for cervical cancer screening (P=.006). A total of 23% (7/30) (95% CI 9.9-42.3) of the mScreening participants received a Pap test; 83% (25/30) of the participants expressed satisfaction with the intervention and 97% (29/30) reported that they would recommend the program to their friends, indicating excellent acceptability and feasibility of the intervention. This study provides evidence of the effectiveness and feasibility of the mScreening intervention. Mobile technology is a promising tool to increase both knowledge and receipt of cervical cancer screening. Given the widespread usage of mobile phones among young adults, a mobile phone-based health intervention could be a low-cost and effective method of reaching populations with low cervical cancer screening rates, using individually tailored messages that cover broad content areas and overcome restrictions to place and time of delivery.
Li, Juan; Yang, Yang; Huan, Huan; Li, Mingxiao; Xi, Beidou; Lv, Ningqing; Wu, Yi; Xie, Yiwen; Li, Xiang; Yang, Jinjin
2016-05-01
This paper presents a system for determining the evaluation and gradation indices of groundwater pollution intensity (GPI). Considering the characteristics of the vadose zone and pollution sources, the system decides which anti-seepage measures should be implemented at the contaminated site. The pollution sources hazards (PSH) and groundwater intrinsic vulnerability (GIV) are graded by the revised Nemerow Pollution Index and an improved DRTAS model, respectively. GPI is evaluated and graded by a double-sided multi-factor coupling model, which is constructed by the matrix method. The contaminated sites are categorized as prior, ordinary, or common sites. From the GPI results, we develop guiding principles for preventing and removing pollution sources, procedural interruption and remediation, and end treatment and monitoring. Thus, we can select appropriate prevention and control technologies (PCT). To screen the technological schemes and optimize the traditional analytical hierarchy process (AHP), we adopt the technique for order preference by the similarity to ideal solution (TOPSIS) method. Our GPI approach and PCT screening are applied to three types of pollution sites: the refuse dump of a rare earth mine development project (a potential pollution source), a chromium slag dump, and a landfill (existing pollution sources). These three sites are identified as ordinary, prior, and ordinary sites, respectively. The anti-seepage materials at the refuse dump should perform as effectively as a 1.5-m-thick clay bed. The chromium slag dump should be preferentially treated by soil flushing and in situ chemical remediation. The landfill should be treated by natural attenuation technology. The proposed PCT screening approach was compared with conventional screening methods results at the three sites and proved feasible and effective. The proposed method can provide technical support for the monitoring and management of groundwater pollution in China. Copyright © 2015. Published by Elsevier B.V.
New approaches to cervical cancer screening in Latin America and the Caribbean.
Herrero, Rolando; Ferreccio, Catterina; Salmerón, Jorge; Almonte, Maribel; Sánchez, Gloria Ines; Lazcano-Ponce, Eduardo; Jerónimo, José
2008-08-19
Cervical cancer remains an important public health problem in the Latin America and Caribbean region (LAC), with an expected significant increase in disease burden in the next decades as a result of population ageing. Prophylactic human papillomavirus (HPV) vaccine is currently unaffordable in LAC countries. However, even if vaccination was implemented, an additional two decades will be required to observe its impact on HPV related disease and cancer. With some exceptions, cytology-based screening programs have been largely ineffective to control the problem in the region, and there is a need for new approaches to the organization of screening and for use of newly developed techniques. Several research groups in LAC have conducted research on new screening methods, some of which are summarized in this paper. A recommendation to reorganize screening programs is presented considering visual inspection for very low resource areas, improvement of cytology where it is operating successfully and HPV DNA testing followed by visual inspection with acetic acid (VIA) or cytology as soon as this method becomes technically and economically sustainable. This could be facilitated by the incorporation of new, low-cost HPV DNA testing methods and the use of self-collected vaginal specimens for selected groups of the population. An important requisite for screening based on HPV testing will be the quality assurance of the laboratory and the technique by validation and certification measures.
Li, Zhaoyong; Wang, Fengmei; Niu, Zengyuan; Luo, Xin; Zhang, Gang; Chen, Junhui
2014-05-01
A method of ultra high performance liquid chromatography-linear ion trap/orbitrap high resolution mass spectrometry (UPLC-LTQ/Orbitrap MS) was established to screen and confirm 24 hormones in cosmetics. Various cosmetic samples were extracted with methanol. The extract was loaded onto a Waters ACQUITY UPLC BEH C18 column (50 mm x 2.1 mm, 1.7 microm) using a gradient elution of acetonitrile/water containing 0.1% (v/v) formic acid for the separation. The accurate mass of quasi-molecular ion was acquired by full scanning of electrostatic field orbitrap. The rapid screening was carried out by the accurate mass of quasi-molecular ion. The confirmation analysis for targeted compounds was performed with the retention time and qualitative fragments obtained by data dependent scan mode. Under the optimal conditions, the 24 hormones were routinely detected with mass accuracy error below 3 x 10(-6) (3 ppm), and good linearities were obtained in their respective linear ranges with correlation coefficients higher than 0.99. The LODs (S/N = 3) of the 24 compounds were < or = 10 microg/kg, which can meet the requirements for the actual screening of cosmetic samples. The developed method was applied to screen the hormones in 50 cosmetic samples. The results demonstrate that the method is a useful tool for the rapid screening and identification of the hormones in cosmetics.
AMIGAS: Building a Cervical Cancer Screening Intervention for Public Health Practice
Smith, Judith Lee; Wilson, Katherine M.; Orians, Carlyn E.; Byrd, Theresa L.
2015-01-01
Background Many barriers to cervical cancer screening for Hispanic women have been documented, but few effective interventions exist. The Community Preventive Services Task Force recommends increasing cervical cancer screening through various methods. Building on this evidence, the Centers for Disease Control and Prevention funded the research and testing phases for an evidence-based and theoretically grounded intervention designed to increase cervical cancer screening among never and rarely screened Hispanic women of Mexican descent. In this article, we describe the development process of the AMIGAS (Ayudando a las Mujeres con Información, Guía, y Amor para su Salud) intervention, highlight the integration of scientific evidence and community-based participatory research principles, and identify opportunities for dissemination, adaptation, and implementation of this intervention. Methods The AMIGAS team was a collaboration among researchers, promotoras (community health workers), and program administrators. The multiyear, multiphase project was conducted in Houston, Texas; El Paso, Texas; and Yakima, Washington. The team completed several rounds of formative research, designed intervention materials and methodology, conducted a randomized controlled trial, created a guide for program administrators, and developed an intervention dissemination plan. Results Trial results demonstrated that AMIGAS was successful in increasing cervical cancer screening among Hispanic women. Adaptation of AMIGAS showed minimal reduction of outcomes. Dissemination efforts are underway to make AMIGAS available in a downloadable format via the Internet. Conclusions Developing a community-based intervention that is evidence-based and theoretically grounded is challenging, time-intensive, and requires collaboration among multiple disciplines. Inclusion of key stakeholders—in particular program deliverers and administrators—and planning for dissemination and translation to practice are integral components of successful intervention design. By providing explicit directions for adaptation for program deliverers, relevant information for program administrators, and access to the intervention via the Internet, AMIGAS is available to help increase cervical cancer screening among Hispanic women and other women disproportionately affected by cervical cancer. PMID:23930983
Berrue, Fabrice; Withers, Sydnor T; Haltli, Brad; Withers, Jo; Kerr, Russell G
2011-03-21
Marine invertebrates have proven to be a rich source of secondary metabolites. The growing recognition that marine microorganisms associated with invertebrate hosts are involved in the biosynthesis of secondary metabolites offers new alternatives for the discovery and development of marine natural products. However, the discovery of microorganisms producing secondary metabolites previously attributed to an invertebrate host poses a significant challenge. This study describes an efficient chemical screening method utilizing a 96-well plate-based bacterial cultivation strategy to identify and isolate microbial producers of marine invertebrate-associated metabolites.
Baek, Hyoung Gee; Liu, Ruiwu; Lam, Kit S
2009-01-01
The one-bead one-compound (OBOC) combinatorial library method enables the rapid generation and screening of millions of discrete chemical compounds on beads. Most of the OBOC screening methods require the library compounds to remain tethered to the bead during screening process. Methods have also been developed to release library compounds from immobilized beads for in situ solution phase or "lawn" assays. However, this latter approach, while extremely powerful, is severely limited by the lack of suitable solid supports for such assays. Here, we report on the development of a novel hydrogel TentaGel shell-core (HTSC) bead in which hydrogel is grafted onto the polystyrene-based TentaGel (TG) bead as an outer shell (5-80 mum thick) via free radical surface-initiated polymerization. This novel shell-core bilayer resin enables the preparation of encoded OBOC combinatorial small molecule libraries, such that the library compounds reside on the highly hydrophilic outer layer and the coding tags reside in the polystyrene-based TG core. Using fluorescein as a model small molecule compound, we have demonstrated that fluorescein molecules that have been linked covalently to the hydrogel shell via a disulfide bond could readily diffuse out of the hydrogel layer into the bead surrounding after reduction with dithiothreitol. In contrast, under identical condition, the released fluorescein molecules remained bound to unmodified TG bead. We have prepared an encoded OBOC small molecule library on the novel shell-core beads and demonstrated that the beads can be readily decoded.
Electrochemical estrogen screen method based on the electrochemical behavior of MCF-7 cells.
Li, Jinlian; Song, Jia; Bi, Sheng; Zhou, Shi; Cui, Jiwen; Liu, Jiguang; Wu, Dongmei
2016-08-05
It was an urgent task to develop quick, cheap and accurate estrogen screen method for evaluating the estrogen effect of the booming chemicals. In this study, the voltammetric behavior between the estrogen-free and normal fragmented MCF-7 cell suspensions were compared, and the electrochemical signal (about 0.68V attributed by xanthine and guanine) of the estrogen-free fragmented MCF-7 cell suspension was obviously lower than that of the normal one. The electrochemistry detection of ex-secretion purines showed that the ability of ex-secretion purines of cells sharp decreased due to the removing of endogenous estrogen. The results indicated that the electrochemical signal of MCF-7 cells was related to the level of intracellular estrogen. When the level of intracellular estrogen was down-regulated, the concentrations of the xanthine and hypoxanthine decreased, which led to the electrochemical signal of MCF-7 cells fall. Based on the electrochemical signal, the electrochemical estrogen screen method was established. The estrogen effect of estradiol, nonylphenol and bisphenol A was evaluated with the electrochemical method, and the result was accordant with that of MTT assay. The electrochemical estrogen screen method was simple, quickly, cheap, objective, and it exploits a new way for the evaluation of estrogenic effects of chemicals. Copyright © 2016. Published by Elsevier B.V.
Screening for small molecule inhibitors of Toxoplasma gondii.
Kortagere, Sandhya
2012-12-01
Toxoplasma gondii, the agent that causes toxoplasmosis, is an opportunistic parasite that infects many mammalian species. It is an obligate intracellular parasite that causes severe congenital neurological and ocular disease mostly in immunocompromised humans. The current regimen of therapy includes only a few medications that often lead to hypersensitivity and toxicity. In addition, there are no vaccines available to prevent the transmission of this agent. Therefore, safer and more effective medicines to treat toxoplasmosis are urgently needed. The author presents in silico and in vitro strategies that are currently used to screen for novel targets and unique chemotypes against T. gondii. Furthermore, this review highlights the screening technologies and characterization of some novel targets and new chemical entities that could be developed into highly efficacious treatments for toxoplasmosis. A number of diverse methods are being used to design inhibitors against T. gondii. These include ligand-based methods, in which drugs that have been shown to be efficacious against other Apicomplexa parasites can be repurposed to identify lead molecules against T. gondii. In addition, structure-based methods use currently available repertoire of structural information in various databases to rationally design small-molecule inhibitors of T. gondii. Whereas the screening methods have their advantages and limitations, a combination of methods is ideally suited to design small-molecule inhibitors of complex parasites such as T. gondii.
NASA Astrophysics Data System (ADS)
Fasolt, Bettina; Hodgins, Micah; Seelecke, Stefan
2016-04-01
Screen printing is used as a method for printing electrodes on silicone thin films for the fabrication of dielectric elastomer transducers (DET). This method can be used to manufacture a multitude of patternable designs for actuator and sensor applications, implementing the same method for prototyping as well as large-scale production. The fabrication of DETs does not only require the development of a flexible, highly conductive electrode material, which adheres to a stretched and unstretched silicone film, but also calls for a thorough understanding of the effects of the different printing parameters. This work studies the influence of screen dimensions (open area, mesh thickness) as well as the influence of multiple-layer- printing on the electrode stiffness, electrical resistance and capacitance as well as actuator performance. The investigation was conducted in a custom-built testing device, which enabled an electro-mechanical characterization of the DET, simultaneously measuring parameters such as strain, voltage, current, force, sheet resistance, capacitance and membrane thickness. Magnified pictures of the electrodes will additionally illustrate the effects of the different printing parameters.
Vidal-Melgosa, Silvia; Pedersen, Henriette L; Schückel, Julia; Arnal, Grégory; Dumon, Claire; Amby, Daniel B; Monrad, Rune Nygaard; Westereng, Bjørge; Willats, William G T
2015-04-03
Carbohydrate-active enzymes have multiple biological roles and industrial applications. Advances in genome and transcriptome sequencing together with associated bioinformatics tools have identified vast numbers of putative carbohydrate-degrading and -modifying enzymes including glycoside hydrolases and lytic polysaccharide monooxygenases. However, there is a paucity of methods for rapidly screening the activities of these enzymes. By combining the multiplexing capacity of carbohydrate microarrays with the specificity of molecular probes, we have developed a sensitive, high throughput, and versatile semiquantitative enzyme screening technique that requires low amounts of enzyme and substrate. The method can be used to assess the activities of single enzymes, enzyme mixtures, and crude culture broths against single substrates, substrate mixtures, and biomass samples. Moreover, we show that the technique can be used to analyze both endo-acting and exo-acting glycoside hydrolases, polysaccharide lyases, carbohydrate esterases, and lytic polysaccharide monooxygenases. We demonstrate the potential of the technique by identifying the substrate specificities of purified uncharacterized enzymes and by screening enzyme activities from fungal culture broths. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.
Screening of 23 β-lactams in foodstuffs by LC-MS/MS using an alkaline QuEChERS-like extraction.
Bessaire, Thomas; Mujahid, Claudia; Beck, Andrea; Tarres, Adrienne; Savoy, Marie-Claude; Woo, Pei-Mun; Mottier, Pascal; Desmarchelier, Aurélien
2018-04-01
A fast and robust high performance LC-MS/MS screening method was developed for the analysis of β-lactam antibiotics in foods of animal origin: eggs, raw milk, processed dairy ingredients, infant formula, and meat- and fish-based products including baby foods. QuEChERS extraction with some adaptations enabled 23 drugs to be simultaneously monitored. Screening target concentrations were set at levels adequate to ensure compliance with current European, Chinese, US and Canadian regulations. The method was fully validated according to the European Community Reference Laboratories Residues Guidelines using 93 food samples of different composition. False-negative and false-positive rates were below 5% for all analytes. The method is adequate for use in high-routine laboratories. A 1-year study was additionally conducted to assess the stability of the 23 analytes in the working standard solution.
Disposable screen-printed sensors for determination of duloxetine hydrochloride
2012-01-01
A screen-printed disposable electrode system for the determination of duloxetine hydrochloride (DL) was developed using screen-printing technology. Homemade printing has been characterized and optimized on the basis of effects of the modifier and plasticizers. The fabricated bi-electrode potentiometric strip containing both working and reference electrodes was used as duloxetine hydrochloride sensor. The proposed sensors worked satisfactorily in the concentration range from 1.0 × 10-6-1.0 × 10-2 mol L-1 with detection limit reaching 5.0 × 10-7 mol L-1 and adequate shelf life of 6 months. The method is accurate, precise and economical. The proposed method has been applied successfully for the analysis of the drug in pure and in its dosage forms. In this method, there is no interference from any common pharmaceutical additives and diluents. Results of the analysis were validated statistically by recovery studies. PMID:22264225
2018-01-01
Although many new anti-infectives have been discovered and developed solely using phenotypic cellular screening and assay optimization, most researchers recognize that structure-guided drug design is more practical and less costly. In addition, a greater chemical space can be interrogated with structure-guided drug design. The practicality of structure-guided drug design has launched a search for the targets of compounds discovered in phenotypic screens. One method that has been used extensively in malaria parasites for target discovery and chemical validation is in vitro evolution and whole genome analysis (IVIEWGA). Here, small molecules from phenotypic screens with demonstrated antiparasitic activity are used in genome-based target discovery methods. In this Review, we discuss the newest, most promising druggable targets discovered or further validated by evolution-based methods, as well as some exceptions. PMID:29451780
Korean Guidelines for Colorectal Cancer Screening and Polyp Detection
Lee, Bo-In; Hong, Sung Pil; Kim, Seong-Eun; Kim, Se Hyung; Hong, Sung Noh; Yang, Dong-Hoon; Shin, Sung Jae; Lee, Suck-Ho; Park, Dong Il; Kim, Young-Ho; Kim, Hyun Jung; Yang, Suk-Kyun; Kim, Hyo Jong; Jeon, Hae Jeong
2012-01-01
Now colorectal cancer is the second most common cancer in males and the fourth most common cancer in females in Korea. Since most of colorectal cancers occur after the prolonged transformation of adenomas into carcinomas, early detection and removal of colorectal adenomas are one of the most effective methods to prevent colorectal cancer. Considering the increasing incidence of colorectal cancer and polyps in Korea, it is very important to establish Korean guideline for colorectal cancer screening and polyp detection. The guideline was developed by the Korean Multi-Society Take Force and we tried to establish the guideline by evidence-based methods. Parts of the statements were draw by systematic reviews and meta-analyses. Herein we discussed epidemiology of colorectal cancers and adenomas in Korea and optimal methods for screening of colorectal cancer and detection of adenomas including fecal occult blood tests, radiologic tests, and endoscopic examinations. PMID:22741131
Fast Estimation of Dietary Fiber Content in Apple.
Le Gall, Sophie; Even, Sonia; Lahaye, Marc
2016-02-17
Dietary fibers (DF) are one of the nutritional benefits of fleshy fruit consumption that is becoming a quality criterion for genetic selection by breeders. However, the AOAC total DF content determination is not readily amenable for screening large fruit collections. A new screening method of DF content in an apple collection based on the automated preparation of cell wall material as an alcohol-insoluble residue (AIR) is proposed. The yield of AIR from 27 apple genotypes was compared with DF measured according to AOAC method 985.29. Although residual protein content in AIRs did not affect DF measurement, subtraction of starch content above 3% dry weight in AIRs was needed to agree with AOAC measured DF. A fast colorimetric screening of starch in AIR was developed to detect samples needing correction. The proposed method may prove useful for the rapid determination of DF in collections of other fleshy fruit besides apple.
Dolado, Ignacio; Nieto, Joan; Saraiva, Maria João M; Arsequell, Gemma; Valencia, Gregori; Planas, Antoni
2005-01-01
Stabilization of tetrameric transthyretin (TTR) by binding of small ligands is a current strategy aimed at inhibiting amyloid fibrillogenesis in transthyretin-associated pathologies, such as senile systemic amyloidosis (SSA) and familial amyloidotic polyneuropathy (FAP). A kinetic assay is developed for rapid evaluation of compounds as potential in vitro inhibitors in a high-throughput screening format. It is based on monitoring the time-dependent increase of absorbance due to turbidity occurring by acid-induced protein aggregation. The method uses the highly amyloidogenic Y78F mutant of human transthyretin (heterogously expressed in Escherichia coli cells). Initial rates of protein aggregation at different inhibitor concentrations follow a monoexponential dose-response curve from which inhibition parameters are calculated. For the assay development, thyroid hormones and nonsteroidal antiinflamatory drugs were chosen among other reference compounds. Some of them are already known to be in vitro inhibitors of TTR amyloidogenesis. Analysis time is optimized to last 1.5 h, and the method is implemented in microtiter plates for screening of libraries of potential fibrillogenesis inhibitors.
Implementing a method of screening one-well hydraulic barrier design alternatives.
Rubin, Hillel; Shoemaker, Christine A; Köngeter, Jürgen
2009-01-01
This article provides details of applying the method developed by the authors (Rubin et al. 2008b) for screening one-well hydraulic barrier design alternatives. The present article with its supporting information (manual and electronic spreadsheets with a case history example) provides the reader complete details and examples of solving the set of nonlinear equations developed by Rubin et al. (2008b). It allows proper use of the analytical solutions and also depicting the various charts given by Rubin et al. (2008b). The final outputs of the calculations are the required position and the discharge of the pumping well. If the contaminant source is nonaqueous phase liquid (NAPL) entrapped within the aquifer, then the method provides an estimate of the aquifer remediation progress (which is a by-product) due to operating the hydraulic barrier.
USDA-ARS?s Scientific Manuscript database
Emerald ash borer (EAB), a serious invasive forest pest in the United States, has killed millions of North American ash trees and spread to 29 states since it was first detected in 2002 in southern Michigan. Development of a new control method that specifically targets the pest but has no adverse i...
A new method to evaluate the biocontrol potential of single spore isolates of fungal entomopathogens
Posada, Francisco J.; Vega, Fernando E.
2005-01-01
Fifty Beauveria bassiana (Balsamo) Vuillemin (Ascomycota: Hypocreales) strains isolated from the coffee berry borer were used to develop a novel screening method aimed at selecting strains with the highest biocontrol potential. The screening method is based on percent insect mortality, average survival time, mortality distribution, percent spore germination, fungal life cycle duration, and spore production on the insect. Based on these parameters, only 11 strains merited further study. The use of a sound scientific protocol for the selection of promising fungal entomopathogens should lead to more efficient use of time, labor, and financial resources in biological control programs. PMID:17119619
2013-01-01
Background Autism spectrum disorder (ASD) can be difficult to distinguish from other psychiatric disorders. The clinical assessment of ASD is lengthy, and has to be performed by a specialized clinician. Therefore, a screening instrument to aid in the identification of patients who may have undiagnosed ASD should be useful. The purpose of this study was to develop such a screening instrument. Methods Based on the 80 item Ritvo Autism and Asperger Diagnostic Scale-Revised (RAADS-R), we developed a 14 item self-evaluation questionnaire, the RAADS-14 Screen. In total, 135 adults with ASD and 508 psychiatric controls completed the abridged version of the RAADS-R. Results The RAADS-14 Screen score was significantly higher in the ASD group than in the control samples, with a median score of 32 for ASD, 15 for attention deficit hyperactivity disorder, and 11 for other psychiatric disorders (P < 0.001). A cut-off score of 14 or above reached a sensitivity of 97% and a specificity of 46 to 64%. A factor analysis identified three factors consistent with mentalizing deficits, social anxiety, and sensory reactivity relevant for the diagnosis of ASD. The psychometric properties of RAADS-14 Screen were shown to be satisfactory. Conclusions The results of this study indicate that RAADS-14 Screen is a promising measure in screening for ASD in adult psychiatric outpatients. PMID:24321513
Plouffe, David; Brinker, Achim; McNamara, Case; Henson, Kerstin; Kato, Nobutaka; Kuhen, Kelli; Nagle, Advait; Adrián, Francisco; Matzen, Jason T.; Anderson, Paul; Nam, Tae-gyu; Gray, Nathanael S.; Chatterjee, Arnab; Janes, Jeff; Yan, S. Frank; Trager, Richard; Caldwell, Jeremy S.; Schultz, Peter G.; Zhou, Yingyao; Winzeler, Elizabeth A.
2008-01-01
The growing resistance to current first-line antimalarial drugs represents a major health challenge. To facilitate the discovery of new antimalarials, we have implemented an efficient and robust high-throughput cell-based screen (1,536-well format) based on proliferation of Plasmodium falciparum (Pf) in erythrocytes. From a screen of ≈1.7 million compounds, we identified a diverse collection of ≈6,000 small molecules comprised of >530 distinct scaffolds, all of which show potent antimalarial activity (<1.25 μM). Most known antimalarials were identified in this screen, thus validating our approach. In addition, we identified many novel chemical scaffolds, which likely act through both known and novel pathways. We further show that in some cases the mechanism of action of these antimalarials can be determined by in silico compound activity profiling. This method uses large datasets from unrelated cellular and biochemical screens and the guilt-by-association principle to predict which cellular pathway and/or protein target is being inhibited by select compounds. In addition, the screening method has the potential to provide the malaria community with many new starting points for the development of biological probes and drugs with novel antiparasitic activities. PMID:18579783
Testing times: do new prenatal tests signal the end of Down syndrome?
Cole, Robert; Jones, Gareth
2013-03-01
Since 2010, prenatal screening for Down syndrome (DS) has been offered to all pregnant women in New Zealand. The programme has been criticised by several groups, on claims that screening is eugenic and discriminatory towards those with DS. Recently, tests have been developed that may one day prove more efficient than current screening methods. They are an example of 'Non-Invasive Prenatal Diagnosis' (NIPD), which enables diagnosis earlier in pregnancy with less risk of complications. If the current programme raises objections, what threats does this new and seemingly more attractive technology pose to the DS community? We argue that NIPD is simply an extension of current screening methods, raising similar ethical concerns. Presently, the programme shows little evidence of 'eugenics', demonstrated by moderate uptake rates and varying attitudes towards disability. We do not regard the offer of screening to be threatening, as women choose whether or not to be screened depending on their own personal circumstances. One day, prenatal testing may result in fewer people with DS; but past and present trends indicate these individuals will continue to be supported, irrespective of 'group size'. Care and respect for the disabled will remain essential, regardless of a woman's decision over her pregnancy.
Li, Liang; Mustafi, Debarshi; Fu, Qiang; Tereshko, Valentina; Chen, Delai L.; Tice, Joshua D.; Ismagilov, Rustem F.
2006-01-01
High-throughput screening and optimization experiments are critical to a number of fields, including chemistry and structural and molecular biology. The separation of these two steps may introduce false negatives and a time delay between initial screening and subsequent optimization. Although a hybrid method combining both steps may address these problems, miniaturization is required to minimize sample consumption. This article reports a “hybrid” droplet-based microfluidic approach that combines the steps of screening and optimization into one simple experiment and uses nanoliter-sized plugs to minimize sample consumption. Many distinct reagents were sequentially introduced as ≈140-nl plugs into a microfluidic device and combined with a substrate and a diluting buffer. Tests were conducted in ≈10-nl plugs containing different concentrations of a reagent. Methods were developed to form plugs of controlled concentrations, index concentrations, and incubate thousands of plugs inexpensively and without evaporation. To validate the hybrid method and demonstrate its applicability to challenging problems, crystallization of model membrane proteins and handling of solutions of detergents and viscous precipitants were demonstrated. By using 10 μl of protein solution, ≈1,300 crystallization trials were set up within 20 min by one researcher. This method was compatible with growth, manipulation, and extraction of high-quality crystals of membrane proteins, demonstrated by obtaining high-resolution diffraction images and solving a crystal structure. This robust method requires inexpensive equipment and supplies, should be especially suitable for use in individual laboratories, and could find applications in a number of areas that require chemical, biochemical, and biological screening and optimization. PMID:17159147
1982-01-01
bromide is listed as a positive interference. Nitric oxide and nitrogen dioxide can be detected by using the Draeger nitrous fumes detector tube. A... fumes exhibit a delay from the time of exposure to the onset of symptoms. This time delay would not be conducive for a rapid field screening test. It...Dangerous when strongly heated, emits highly toxic fumes . THRESHOLD LIMIT VALUE: No information available PHYSIOLOGICAL EFFECTS: A. Intensely irritating to
Lee, Elliot; Lavieri, Mariel S; Volk, Michael L; Xu, Yongcai
2015-09-01
We investigate the problem faced by a healthcare system wishing to allocate its constrained screening resources across a population at risk for developing a disease. A patient's risk of developing the disease depends on his/her biomedical dynamics. However, knowledge of these dynamics must be learned by the system over time. Three classes of reinforcement learning policies are designed to address this problem of simultaneously gathering and utilizing information across multiple patients. We investigate a case study based upon the screening for Hepatocellular Carcinoma (HCC), and optimize each of the three classes of policies using the indifference zone method. A simulation is built to gauge the performance of these policies, and their performance is compared to current practice. We then demonstrate how the benefits of learning-based screening policies differ across various levels of resource scarcity and provide metrics of policy performance.
Shabbir, Shagufta H.; Regan, Clinton J.; Anslyn, Eric V.
2009-01-01
A general approach to high-throughput screening of enantiomeric excess (ee) and concentration was developed by using indicator displacement assays (IDAs), and the protocol was then applied to the vicinal diol hydrobenzoin. The method involves the sequential utilization of what we define herein as screening, training, and analysis plates. Several enantioselective boronic acid-based receptors were screened by using 96-well plates, both for their ability to discriminate the enantiomers of hydrobenzoin and to find their optimal pairing with indicators resulting in the largest optical responses. The best receptor/indicator combination was then used to train an artificial neural network to determine concentration and ee. To prove the practicality of the developed protocol, analysis plates were created containing true unknown samples of hydrobenzoin generated by established Sharpless asymmetric dihydroxylation reactions, and the best ligand was correctly identified. PMID:19332790
Shabbir, Shagufta H; Regan, Clinton J; Anslyn, Eric V
2009-06-30
A general approach to high-throughput screening of enantiomeric excess (ee) and concentration was developed by using indicator displacement assays (IDAs), and the protocol was then applied to the vicinal diol hydrobenzoin. The method involves the sequential utilization of what we define herein as screening, training, and analysis plates. Several enantioselective boronic acid-based receptors were screened by using 96-well plates, both for their ability to discriminate the enantiomers of hydrobenzoin and to find their optimal pairing with indicators resulting in the largest optical responses. The best receptor/indicator combination was then used to train an artificial neural network to determine concentration and ee. To prove the practicality of the developed protocol, analysis plates were created containing true unknown samples of hydrobenzoin generated by established Sharpless asymmetric dihydroxylation reactions, and the best ligand was correctly identified.
Molecular Screening Tools to Study Arabidopsis Transcription Factors
Wehner, Nora; Weiste, Christoph; Dröge-Laser, Wolfgang
2011-01-01
In the model plant Arabidopsis thaliana, more than 2000 genes are estimated to encode transcription factors (TFs), which clearly emphasizes the importance of transcriptional control. Although genomic approaches have generated large TF open reading frame (ORF) collections, only a limited number of these genes is functionally characterized, yet. This review evaluates strategies and methods to identify TF functions. In particular, we focus on two recently developed TF screening platforms, which make use of publically available GATEWAY®-compatible ORF collections. (1) The Arabidopsis thaliana TF ORF over-Expression (AtTORF-Ex) library provides pooled collections of transgenic lines over-expressing HA-tagged TF genes, which are suited for screening approaches to define TF functions in stress defense and development. (2) A high-throughput microtiter plate based protoplast trans activation (PTA) system has been established to screen for TFs which are regulating a given promoter:Luciferase construct in planta. PMID:22645547
Sanders, Melanie; McPartlin, Daniel; Moran, Kara; Guo, Yirong; Eeckhout, Mia; O'Kennedy, Richard; De Saeger, Sarah; Maragos, Chris
2016-04-11
A sample preparation method was developed for the screening of deoxynivalenol (DON) in wheat and wheat dust. Extraction was carried out with water and was successful due to the polar character of DON. For detection, an enzyme-linked immunosorbent assay (ELISA) was compared to the sensor-based techniques of surface plasmon resonance (SPR) and biolayer interferometry (BLI) in terms of sensitivity, affinity and matrix effect. The matrix effects from wheat and wheat dust using SPR were too high to further use this screenings method. The preferred ELISA and BLI methods were validated according to the criteria established in Commission Regulation 519/2014/EC and Commission Decision 2002/657/EC. A small survey was executed on 16 wheat lots and their corresponding dust samples using the validated ELISA method. A linear correlation (r = 0.889) was found for the DON concentration in dust versus the DON concentration in wheat (LOD wheat: 233 μg/kg, LOD wheat dust: 458 μg/kg).
Scoring systems for the Clock Drawing Test: A historical review
Spenciere, Bárbara; Alves, Heloisa; Charchat-Fichman, Helenice
2017-01-01
The Clock Drawing Test (CDT) is a simple neuropsychological screening instrument that is well accepted by patients and has solid psychometric properties. Several different CDT scoring methods have been developed, but no consensus has been reached regarding which scoring method is the most accurate. This article reviews the literature on these scoring systems and the changes they have undergone over the years. Historically, different types of scoring systems emerged. Initially, the focus was on screening for dementia, and the methods were both quantitative and semi-quantitative. Later, the need for an early diagnosis called for a scoring system that can detect subtle errors, especially those related to executive function. Therefore, qualitative analyses began to be used for both differential and early diagnoses of dementia. A widely used qualitative method was proposed by Rouleau et al. (1992). Tracing the historical path of these scoring methods is important for developing additional scoring systems and furthering dementia prevention research. PMID:29213488
Wang, Jian; Leung, Daniel
2012-08-01
This paper discusses the analytical challenges to develop a generic extraction procedure to analyze or screen multi-class veterinary drugs in milk and honey using ultra-high pressure liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC QqTOF MS). The veterinary drugs in this study included aminoglycosides, endectocides, fluoroquinolones, ionophores, β-lactams or penicillins, macrolides, NSAIDs, phenicols, sulfonamides and tetracyclines. Veterinary drugs were extracted using a QuEChERS (quick, easy, cheap, effective, rugged, and safe) method, which entailed the use of acetonitrile containing 1% acetic acid, sodium acetate, ethylenediaminetetra acetic acid disodium (EDTA) and magnesium sulfate, and no clean-up was performed. Chromatographic separation was achieved on a reversed-phase Acquity UPLC BEH C(18) , 100 × 2.1 mm, 1.7 µm column with 0.1% formic acid and 10 mM ammonium formate in water, and acetonitrile as mobile phases. Due to poor chromatographic retention, aminoglycosides were first dropped from the list, and because of poor extractability, β-lactams and tetracyclines were also excluded from the method. The method was able to quantify 31 or screen up to 54 drugs (unbound) in honey, and to quantify 34 or screen up to 59 drugs in milk. UHPLC QqTOF data were acquired in TOF MS full-scan mode that allowed both quantification and confirmation of veterinary drugs and identification of their degradation products in samples. The method could achieve detection limits as low as 1 µg/kg with analytical range from 1 to 100 µg/kg. The developed method was intended to be used for screening of as many analytes as possible in one single analysis, or unequivocal confirmation of positive findings and degradation product identification based on accurate mass measurement and isotopic patterns. © Her Majesty the Queen in Right of Canada 2012. Reproduced with the permission of the Minister of Agriculture.
Kaga, Chiaki; Okochi, Mina; Tomita, Yasuyuki; Kato, Ryuji; Honda, Hiroyuki
2008-03-01
We developed a method of effective peptide screening that combines experiments and computational analysis. The method is based on the concept that screening efficiency can be enhanced from even limited data by use of a model derived from computational analysis that serves as a guide to screening and combining the model with subsequent repeated experiments. Here we focus on cell-adhesion peptides as a model application of this peptide-screening strategy. Cell-adhesion peptides were screened by use of a cell-based assay of a peptide array. Starting with the screening data obtained from a limited, random 5-mer library (643 sequences), a rule regarding structural characteristics of cell-adhesion peptides was extracted by fuzzy neural network (FNN) analysis. According to this rule, peptides with unfavored residues in certain positions that led to inefficient binding were eliminated from the random sequences. In the restricted, second random library (273 sequences), the yield of cell-adhesion peptides having an adhesion rate more than 1.5-fold to that of the basal array support was significantly high (31%) compared with the unrestricted random library (20%). In the restricted third library (50 sequences), the yield of cell-adhesion peptides increased to 84%. We conclude that a repeated cycle of experiments screening limited numbers of peptides can be assisted by the rule-extracting feature of FNN.
Pei, Fen; Jin, Hongwei; Zhou, Xin; Xia, Jie; Sun, Lidan; Liu, Zhenming; Zhang, Liangren
2015-11-01
Toll-like receptor 8 agonists, which activate adaptive immune responses by inducing robust production of T-helper 1-polarizing cytokines, are promising candidates for vaccine adjuvants. As the binding site of toll-like receptor 8 is large and highly flexible, virtual screening by individual method has inevitable limitations; thus, a comprehensive comparison of different methods may provide insights into seeking effective strategy for the discovery of novel toll-like receptor 8 agonists. In this study, the performance of knowledge-based pharmacophore, shape-based 3D screening, and combined strategies was assessed against a maximum unbiased benchmarking data set containing 13 actives and 1302 decoys specialized for toll-like receptor 8 agonists. Prior structure-activity relationship knowledge was involved in knowledge-based pharmacophore generation, and a set of antagonists was innovatively used to verify the selectivity of the selected knowledge-based pharmacophore. The benchmarking data set was generated from our recently developed 'mubd-decoymaker' protocol. The enrichment assessment demonstrated a considerable performance through our selected three-layer virtual screening strategy: knowledge-based pharmacophore (Phar1) screening, shape-based 3D similarity search (Q4_combo), and then a Gold docking screening. This virtual screening strategy could be further employed to perform large-scale database screening and to discover novel toll-like receptor 8 agonists. © 2015 John Wiley & Sons A/S.
The extended Fourier pseudospectral time-domain method for atmospheric sound propagation.
Hornikx, Maarten; Waxler, Roger; Forssén, Jens
2010-10-01
An extended Fourier pseudospectral time-domain (PSTD) method is presented to model atmospheric sound propagation by solving the linearized Euler equations. In this method, evaluation of spatial derivatives is based on an eigenfunction expansion. Evaluation on a spatial grid requires only two spatial points per wavelength. Time iteration is done using a low-storage optimized six-stage Runge-Kutta method. This method is applied to two-dimensional non-moving media models, one with screens and one for an urban canyon, with generally high accuracy in both amplitude and phase. For a moving atmosphere, accurate results have been obtained in models with both a uniform and a logarithmic wind velocity profile over a rigid ground surface and in the presence of a screen. The method has also been validated for three-dimensional sound propagation over a screen. For that application, the developed method is in the order of 100 times faster than the second-order-accurate FDTD solution to the linearized Euler equations. The method is found to be well suited for atmospheric sound propagation simulations where effects of complex meteorology and straight rigid boundary surfaces are to be investigated.
NASA Astrophysics Data System (ADS)
Qiu, Yuchen; Wang, Yunzhi; Yan, Shiju; Tan, Maxine; Cheng, Samuel; Liu, Hong; Zheng, Bin
2016-03-01
In order to establish a new personalized breast cancer screening paradigm, it is critically important to accurately predict the short-term risk of a woman having image-detectable cancer after a negative mammographic screening. In this study, we developed and tested a novel short-term risk assessment model based on deep learning method. During the experiment, a number of 270 "prior" negative screening cases was assembled. In the next sequential ("current") screening mammography, 135 cases were positive and 135 cases remained negative. These cases were randomly divided into a training set with 200 cases and a testing set with 70 cases. A deep learning based computer-aided diagnosis (CAD) scheme was then developed for the risk assessment, which consists of two modules: adaptive feature identification module and risk prediction module. The adaptive feature identification module is composed of three pairs of convolution-max-pooling layers, which contains 20, 10, and 5 feature maps respectively. The risk prediction module is implemented by a multiple layer perception (MLP) classifier, which produces a risk score to predict the likelihood of the woman developing short-term mammography-detectable cancer. The result shows that the new CAD-based risk model yielded a positive predictive value of 69.2% and a negative predictive value of 74.2%, with a total prediction accuracy of 71.4%. This study demonstrated that applying a new deep learning technology may have significant potential to develop a new short-term risk predicting scheme with improved performance in detecting early abnormal symptom from the negative mammograms.
Biomass Characterization | Bioenergy | NREL
analytical methods for biomass characterization available for downloading. View the Biomass Compositional Methods Molecular Beam Mass Spectrometry Photo of a man in front of multiple computer screens that present Characterization of Biomass We develop new methods and tools to understand the chemical composition of raw biomass
Vaez, Nara; Desgualdo-Pereira, Liliane; Paglialonga, Alessia
2014-01-01
This paper describes the development of a speech-in-noise test for hearing screening and surveillance in Brazilian Portuguese based on the evaluation of suprathreshold acuity performances. The SUN test (Speech Understanding in Noise) consists of a list of intervocalic consonants in noise presented in a multiple-choice paradigm by means of a touch screen. The test provides one out of three possible results: “a hearing check is recommended” (red light), “a hearing check would be advisable” (yellow light), and “no hearing difficulties” (green light) (Paglialonga et al., Comput. Biol. Med. 2014). This novel test was developed in a population of 30 normal hearing young adults and 101 adults with varying degrees of hearing impairment and handicap, including normal hearing. The test had 84% sensitivity and 76% specificity compared to conventional pure-tone screening and 83% sensitivity and 86% specificity to detect disabling hearing impairment. The test outcomes were in line with the degree of self-perceived hearing handicap. The results found here paralleled those reported in the literature for the SUN test and for conventional speech-in-noise measures. This study showed that the proposed test might be a viable method to identify individuals with hearing problems to be referred to further audiological assessment and intervention. PMID:25247181
Baker, Nicholas E.; Li, Ke; Quiquand, Manon; Ruggiero, Robert; Wang, Lan-Hsin
2014-01-01
The eye has been one of the most intensively studied organs in Drosophila. The wealth of knowledge about its development, as well as the reagents that have been developed, and the fact that the eye is dispensable for survival, also make the eye suitable for genetic interaction studies and genetic screens. This chapter provides a brief overview of the methods developed to image and probe eye development at multiple developmental stages, including live imaging, immunostaining of fixed tissues, in situ hybridizations, and scanning electron microscopy and color photography of adult eyes. Also summarized are genetic approaches that can be performed in the eye, including mosaic analysis and conditional mutation, gene misexpression and knockdown, and forward genetic and modifier screens. PMID:24784530
Sridhar, L; Karthikraj, R; Lakshmi, V V S; Raju, N Prasada; Prabhakar, S
2014-08-01
Rapid detection and identification of chemical warfare agents and related precursors/degradation products in various environmental matrices is of paramount importance for verification of standards set by the chemical weapons convention (CWC). Nitrogen mustards, N,N-dialkylaminoethyl-2-chlorides, N,N-dialkylaminoethanols, N-alkyldiethanolamines, and triethanolamine, which are listed CWC scheduled chemicals, are prone to undergo N-oxidation in environmental matrices or during decontamination process. Thus, screening of the oxidized products of these compounds is also an important task in the verification process because the presence of these products reveals alleged use of nitrogen mustards or precursors of VX compounds. The N-oxides of aminoethanols and aminoethylchlorides easily produce [M + H](+) ions under electrospray ionization conditions, and their collision-induced dissociation spectra include a specific neutral loss of 48 u (OH + CH2OH) and 66 u (OH + CH2Cl), respectively. Based on this specific fragmentation, a rapid screening method was developed for screening of the N-oxides by applying neutral loss scan technique. The method was validated and the applicability of the method was demonstrated by analyzing positive and negative samples. The method was useful in the detection of N-oxides of aminoethanols and aminoethylchlorides in environmental matrices at trace levels (LOD, up to 500 ppb), even in the presence of complex masking agents, without the use of time-consuming sample preparation methods and chromatographic steps. This method is advantageous for the off-site verification program and also for participation in official proficiency tests conducted by the Organization for the Prohibition of Chemical Weapons (OPCW), the Netherlands. The structure of N-oxides can be confirmed by the MS/MS experiments on the detected peaks. A liquid chromatography-mass spectrometry (LC-MS) method was developed for the separation of isomeric N-oxides of aminoethanols and aminoethylchlorides using a C18 Hilic column. Critical isomeric compounds can be confirmed by LC-MS/MS experiments, after detecting the N-oxides from the neutral loss scanning method.
Chemical Safety Alert: Identifying Chemical Reactivity Hazards Preliminary Screening Method
Introduces small-to-medium-sized facilities to a method developed by Center for Chemical Process Safety (CCPS), based on a series of twelve yes-or-no questions to help determine hazards in warehousing, repackaging, blending, mixing, and processing.
Development of the Stress of Immigration Survey: A Field Test Among Mexican Immigrant Women.
Sternberg, Rosa Maria; Nápoles, Anna Maria; Gregorich, Steven; Paul, Steven; Lee, Kathryn A; Stewart, Anita L
2016-01-01
The Stress of Immigration Survey (SOIS) is a screening tool used to assess immigration-related stress. The mixed methods approach included concept development, pretesting, field testing, and psychometric evaluation in a sample of 131 low-income women of Mexican descent. The 21-item SOIS screens for stress related to language, immigrant status, work issues, yearning for family and home country, and cultural dissonance. Mean scores ranged from 3.6 to 4.4 (a scale of 1-5, higher is more stress). Cronbach α values were more than 0.80 for all subscales. The SOIS may be a useful screening tool for detecting high levels of immigration-related stress in low-income Mexican immigrant women.
Functional screening of selective mitochondrial inhibitors of Plasmodium.
Gomez-Lorenzo, Maria G; Rodríguez-Alejandre, Ane; Moliner-Cubel, Sonia; Martínez-Hoyos, María; Bahamontes-Rosa, Noemí; Gonzalez Del Rio, Rubén; Ródenas, Carolina; Fuente, Jesús de la; Lavandera, Jose Luis; García-Bustos, Jose F; Mendoza-Losana, Alfonso
2018-05-09
Phenotypic screening has produced most of the new chemical entities currently in clinical development for malaria, plus many lead compounds active against Plasmodium falciparum asexual stages. However, lack of knowledge about the mode of action of these compounds delays and may even hamper their future development. Identifying the mode of action of the inhibitors greatly helps to prioritise compounds for further development as novel antimalarials. Here we describe a whole-cell method to detect inhibitors of the mitochondrial electron transport chain, using oxygen consumption as high throughput readout in 384-well plate format. The usefulness of the method has been confirmed with the Tres Cantos Antimalarial Compound Set (TCAMS). The assay identified 124 respiratory inhibitors in TCAMS, seven of which were novel anti-plasmodial chemical structures never before described as mitochondrial inhibitors. Copyright © 2018. Published by Elsevier Ltd.
Cervical Cancer Prevention in the 21st Century: Cost Is Not the Only Issue
Hurlburt, Sarah; Greeson, Dana
2011-01-01
The wide publicity related to human papillomavirus (HPV) vaccines has led to a sense that HPV vaccine programs are inevitable in both developed and developing countries, whereas 2 existing methods of screening—visual inspection with ascetic acid (VIA) and DNA testing—have received much less attention. These screening methods detect cervical lesions better than does the Papanicolaou test and allow immediate treatment, minimizing loss to follow-up. These advantages may outweigh the strengths of HPV vaccines. Priority should be given to improving screening coverage with VIA and DNA tests, focusing on women older than 30 years and underserved populations in all countries. This approach will save the lives of millions of women who have already been exposed to HPV and will develop cervical cancer during the next 20 years. PMID:21778496
Taksler, Glen B; Perzynski, Adam T; Kattan, Michael W
2017-04-01
Recommendations for colorectal cancer screening encourage patients to choose among various screening methods based on individual preferences for benefits, risks, screening frequency, and discomfort. We devised a model to illustrate how individuals with varying tolerance for screening complications risk might decide on their preferred screening strategy. We developed a discrete-time Markov mathematical model that allowed hypothetical individuals to maximize expected lifetime utility by selecting screening method, start age, stop age, and frequency. Individuals could choose from stool-based testing every 1 to 3 years, flexible sigmoidoscopy every 1 to 20 years with annual stool-based testing, colonoscopy every 1 to 20 years, or no screening. We compared the life expectancy gained from the chosen strategy with the life expectancy available from a benchmark strategy of decennial colonoscopy. For an individual at average risk of colorectal cancer who was risk neutral with respect to screening complications (and therefore was willing to undergo screening if it would actuarially increase life expectancy), the model predicted that he or she would choose colonoscopy every 10 years, from age 53 to 73 years, consistent with national guidelines. For a similar individual who was moderately averse to screening complications risk (and therefore required a greater increase in life expectancy to accept potential risks of colonoscopy), the model predicted that he or she would prefer flexible sigmoidoscopy every 12 years with annual stool-based testing, with 93% of the life expectancy benefit of decennial colonoscopy. For an individual with higher risk aversion, the model predicted that he or she would prefer 2 lifetime flexible sigmoidoscopies, 20 years apart, with 70% of the life expectancy benefit of decennial colonoscopy. Mathematical models may formalize how individuals with different risk attitudes choose between various guideline-recommended colorectal cancer screening strategies.
Jago, R; Zahra, J; Edwards, M J; Kesten, J M; Solomon-Moore, E; Thompson, J L; Sebire, S J
2016-03-01
The present study used qualitative methods to: (1) examine the strategies that were used by parents of children aged 5-6 years to manage screen viewing; (2) identify key factors that affect the implementation of the strategies and (3) develop suggestions for future intervention content. Telephone interviews were conducted with parents of children aged 5-6 years participating in a larger study. Interviews were transcribed verbatim and analysed using an inductive and deductive content analysis. Coding and theme generation was iterative and refined throughout. Parents were recruited through 57 primary schools located in the greater Bristol area (UK). 53 parents of children aged 5-6 years. Parents reported that for many children, screen viewing was a highly desirable behaviour that was difficult to manage, and that parents used the provision of screen viewing as a tool for reward and/or punishment. Parents managed screen viewing by setting limits in relation to daily events such as meals, before and after school, and bedtime. Screen-viewing rules were often altered depending on parental preferences and tasks. Inconsistent messaging within and between parents represented a source of conflict at times. Potential strategies to facilitate reducing screen viewing were identified, including setting screen-viewing limits in relation to specific events, collaborative rule setting, monitoring that involves mothers, fathers and the child, developing a family-specific set of alternative activities to screen viewing and developing a child's ability to self-monitor their own screen viewing. Managing screen viewing is a challenge for many parents and can often cause tension in the home. The data presented in this paper provide key suggestions of new approaches that could be incorporated into behaviour change programmes to reduce child screen viewing. 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/
Jago, R; Zahra, J; Edwards, M J; Kesten, J M; Solomon-Moore, E; Thompson, J L; Sebire, S J
2016-01-01
Objectives The present study used qualitative methods to: (1) examine the strategies that were used by parents of children aged 5–6 years to manage screen viewing; (2) identify key factors that affect the implementation of the strategies and (3) develop suggestions for future intervention content. Design Telephone interviews were conducted with parents of children aged 5–6 years participating in a larger study. Interviews were transcribed verbatim and analysed using an inductive and deductive content analysis. Coding and theme generation was iterative and refined throughout. Setting Parents were recruited through 57 primary schools located in the greater Bristol area (UK). Participants 53 parents of children aged 5–6 years. Results Parents reported that for many children, screen viewing was a highly desirable behaviour that was difficult to manage, and that parents used the provision of screen viewing as a tool for reward and/or punishment. Parents managed screen viewing by setting limits in relation to daily events such as meals, before and after school, and bedtime. Screen-viewing rules were often altered depending on parental preferences and tasks. Inconsistent messaging within and between parents represented a source of conflict at times. Potential strategies to facilitate reducing screen viewing were identified, including setting screen-viewing limits in relation to specific events, collaborative rule setting, monitoring that involves mothers, fathers and the child, developing a family-specific set of alternative activities to screen viewing and developing a child's ability to self-monitor their own screen viewing. Conclusions Managing screen viewing is a challenge for many parents and can often cause tension in the home. The data presented in this paper provide key suggestions of new approaches that could be incorporated into behaviour change programmes to reduce child screen viewing. PMID:26932143
Reynolds, Christopher R; Muggleton, Stephen H; Sternberg, Michael J E
2015-01-01
The use of virtual screening has become increasingly central to the drug development pipeline, with ligand-based virtual screening used to screen databases of compounds to predict their bioactivity against a target. These databases can only represent a small fraction of chemical space, and this paper describes a method of exploring synthetic space by applying virtual reactions to promising compounds within a database, and generating focussed libraries of predicted derivatives. A ligand-based virtual screening tool Investigational Novel Drug Discovery by Example (INDDEx) is used as the basis for a system of virtual reactions. The use of virtual reactions is estimated to open up a potential space of 1.21×1012 potential molecules. A de novo design algorithm known as Partial Logical-Rule Reactant Selection (PLoRRS) is introduced and incorporated into the INDDEx methodology. PLoRRS uses logical rules from the INDDEx model to select reactants for the de novo generation of potentially active products. The PLoRRS method is found to increase significantly the likelihood of retrieving molecules similar to known actives with a p-value of 0.016. Case studies demonstrate that the virtual reactions produce molecules highly similar to known actives, including known blockbuster drugs. PMID:26583052
Improving colorectal cancer screening: fact and fantasy
NASA Astrophysics Data System (ADS)
Van Dam, Jacques
2008-02-01
Premalignant diseases of the gastrointestinal tract, such as Barrett's esophagus, long-standing ulcerative colitis, and adenomatous polyps, have a significantly increased risk for development of adenocarcinoma, most often through an intermediate stage of dysplasia. Adenocarcinoma of the colon is the second most common cancer in the United States. Because patients with colorectal cancer often present with advanced disease, the outcomes are associated with significant morbidity and mortality. Effective methods of early detection are essential. As non-polypoid dysplasia is not visible using conventional endoscopy, surveillance of patients with Barrett's esophagus and ulcerative colitis is performed via a system in which multiple random biopsies are obtained at prescribed intervals. Sampling error and missed diagnoses occur frequently and render current screening methods inadequate. Also, the examination of a tissue biopsy is time consuming and costly, and significant intra- and inter-observer variation may occur. The newer methods discussed herein demonstrate the potential to solve these problems by early detection of disease with high sensitivity and specificity. Conventional endoscopy is based on the observation of white light reflected off the tissue surface. Subtle changes in color and shadow reveal structural changes. New developments in optical imaging go beyond white light, exploiting other properties of light. Several promising methods will be discussed at this meeting and shall be briefly discussed below. However, few such imaging modalities have arrived at our clinical practice. Some much more practical methods to improve colorectal cancer screening are currently being evaluated for their clinical impact. These methods seek to overcome limitations other than those of detecting dysplasia not visible under white light endoscopy. The current standard practice of colorectal cancer screening utilizes colonoscopy, an uncomfortable, sometimes difficult medical procedure. Efforts to improve the practice of colonoscopy will be described. Another limitation of the current practice is the inability to detect polypoid neoplasia that is hidden from view under white light imaging by the natural folds that occur within the colon. A device to overcome this limitation will also be described. Efforts to improve colorectal cancer screening (and thereby decrease the death rate of this second leading cause of cancer death in the United States) are progressing in many arenas. The researcher, basic or clinical, should maintain an up to date overview of the field and how each new technological advance is likely to have a role in the screening and early detection of colorectal cancer.
Estimating the cost of cervical cancer screening in five developing countries
Goldhaber-Fiebert, Jeremy D; Goldie, Sue J
2006-01-01
Background Cost-effectiveness analyses (CEAs) can provide useful information to policymakers concerned with the broad allocation of resources as well as to local decision makers choosing between different options for reducing the burden from a single disease. For the latter, it is important to use country-specific data when possible and to represent cost differences between countries that might make one strategy more or less attractive than another strategy locally. As part of a CEA of cervical cancer screening in five developing countries, we supplemented limited primary cost data by developing other estimation techniques for direct medical and non-medical costs associated with alternative screening approaches using one of three initial screening tests: simple visual screening, HPV DNA testing, and cervical cytology. Here, we report estimation methods and results for three cost areas in which data were lacking. Methods To supplement direct medical costs, including staff, supplies, and equipment depreciation using country-specific data, we used alternative techniques to quantify cervical cytology and HPV DNA laboratory sample processing costs. We used a detailed quantity and price approach whose face validity was compared to an adaptation of a US laboratory estimation methodology. This methodology was also used to project annual sample processing capacities for each laboratory type. The cost of sample transport from the clinic to the laboratory was estimated using spatial models. A plausible range of the cost of patient time spent seeking and receiving screening was estimated using only formal sector employment and wages as well as using both formal and informal sector participation and country-specific minimum wages. Data sources included primary data from country-specific studies, international databases, international prices, and expert opinion. Costs were standardized to year 2000 international dollars using inflation adjustment and purchasing power parity. Results Cervical cytology laboratory processing costs were I$1.57–3.37 using the quantity and price method compared to I$1.58–3.02 from the face validation method. HPV DNA processing costs were I$6.07–6.59. Rural laboratory transport costs for cytology were I$0.12–0.64 and I$0.14–0.74 for HPV DNA laboratories. Under assumptions of lower resource efficiency, these estimates increased to I$0.42–0.83 and I$0.54–1.06. Estimates of the value of an hour of patient time using only formal sector participation were I$0.07–4.16, increasing to I$0.30–4.80 when informal and unpaid labor was also included. The value of patient time for traveling, waiting, and attending a screening visit was I$0.68–17.74. With the total cost of screening for cytology and HPV DNA testing ranging from I$4.85–40.54 and I$11.30–48.77 respectively, the cost of the laboratory transport, processing, and patient time accounted for 26–66% and 33–65% of the total costs. From a payer perspective, laboratory transport and processing accounted for 18–48% and 25–60% of total direct medical costs of I$4.11–19.96 and I$10.57–28.18 respectively. Conclusion Cost estimates of laboratory processing, sample transport, and patient time account for a significant proportion of total cervical cancer screening costs in five developing countries and provide important inputs for CEAs of alternative screening modalities. PMID:16887041
Fukunishi, Yoshifumi; Mikami, Yoshiaki; Nakamura, Haruki
2005-09-01
We developed a new method to evaluate the distances and similarities between receptor pockets or chemical compounds based on a multi-receptor versus multi-ligand docking affinity matrix. The receptors were classified by a cluster analysis based on calculations of the distance between receptor pockets. A set of low homologous receptors that bind a similar compound could be classified into one cluster. Based on this line of reasoning, we proposed a new in silico screening method. According to this method, compounds in a database were docked to multiple targets. The new docking score was a slightly modified version of the multiple active site correction (MASC) score. Receptors that were at a set distance from the target receptor were not included in the analysis, and the modified MASC scores were calculated for the selected receptors. The choice of the receptors is important to achieve a good screening result, and our clustering of receptors is useful to this purpose. This method was applied to the analysis of a set of 132 receptors and 132 compounds, and the results demonstrated that this method achieves a high hit ratio, as compared to that of a uniform sampling, using a receptor-ligand docking program, Sievgene, which was newly developed with a good docking performance yielding 50.8% of the reconstructed complexes at a distance of less than 2 A RMSD.
Efficient discovery of responses of proteins to compounds using active learning
2014-01-01
Background Drug discovery and development has been aided by high throughput screening methods that detect compound effects on a single target. However, when using focused initial screening, undesirable secondary effects are often detected late in the development process after significant investment has been made. An alternative approach would be to screen against undesired effects early in the process, but the number of possible secondary targets makes this prohibitively expensive. Results This paper describes methods for making this global approach practical by constructing predictive models for many target responses to many compounds and using them to guide experimentation. We demonstrate for the first time that by jointly modeling targets and compounds using descriptive features and using active machine learning methods, accurate models can be built by doing only a small fraction of possible experiments. The methods were evaluated by computational experiments using a dataset of 177 assays and 20,000 compounds constructed from the PubChem database. Conclusions An average of nearly 60% of all hits in the dataset were found after exploring only 3% of the experimental space which suggests that active learning can be used to enable more complete characterization of compound effects than otherwise affordable. The methods described are also likely to find widespread application outside drug discovery, such as for characterizing the effects of a large number of compounds or inhibitory RNAs on a large number of cell or tissue phenotypes. PMID:24884564
Development of a fully automatic scheme for detection of masses in whole breast ultrasound images.
Ikedo, Yuji; Fukuoka, Daisuke; Hara, Takeshi; Fujita, Hiroshi; Takada, Etsuo; Endo, Tokiko; Morita, Takako
2007-11-01
Ultrasonography has been used for breast cancer screening in Japan. Screening using a conventional hand-held probe is operator dependent and thus it is possible that some areas of the breast may not be scanned. To overcome such problems, a mechanical whole breast ultrasound (US) scanner has been proposed and developed for screening purposes. However, another issue is that radiologists might tire while interpreting all images in a large-volume screening; this increases the likelihood that masses may remain undetected. Therefore, the aim of this study is to develop a fully automatic scheme for the detection of masses in whole breast US images in order to assist the interpretations of radiologists and potentially improve the screening accuracy. The authors database comprised 109 whole breast US imagoes, which include 36 masses (16 malignant masses, 5 fibroadenomas, and 15 cysts). A whole breast US image with 84 slice images (interval between two slice images: 2 mm) was obtained by the ASU-1004 US scanner (ALOKA Co., Ltd., Japan). The feature based on the edge directions in each slice and a method for subtracting between the slice images were used for the detection of masses in the authors proposed scheme. The Canny edge detector was applied to detect edges in US images; these edges were classified as near-vertical edges or near-horizontal edges using a morphological method. The positions of mass candidates were located using the near-vertical edges as a cue. Then, the located positions were segmented by the watershed algorithm and mass candidate regions were detected using the segmented regions and the low-density regions extracted by the slice subtraction method. For the removal of false positives (FPs), rule-based schemes and a quadratic discriminant analysis were applied for the distribution between masses and FPs. As a result, the sensitivity of the authors scheme for the detection of masses was 80.6% (29/36) with 3.8 FPs per whole breast image. The authors scheme for a computer-aided detection may be useful in improving the screening performance and efficiency.
Developing science gateways for drug discovery in a grid environment.
Pérez-Sánchez, Horacio; Rezaei, Vahid; Mezhuyev, Vitaliy; Man, Duhu; Peña-García, Jorge; den-Haan, Helena; Gesing, Sandra
2016-01-01
Methods for in silico screening of large databases of molecules increasingly complement and replace experimental techniques to discover novel compounds to combat diseases. As these techniques become more complex and computationally costly we are faced with an increasing problem to provide the research community of life sciences with a convenient tool for high-throughput virtual screening on distributed computing resources. To this end, we recently integrated the biophysics-based drug-screening program FlexScreen into a service, applicable for large-scale parallel screening and reusable in the context of scientific workflows. Our implementation is based on Pipeline Pilot and Simple Object Access Protocol and provides an easy-to-use graphical user interface to construct complex workflows, which can be executed on distributed computing resources, thus accelerating the throughput by several orders of magnitude.
Liu, Rui; Li, Wei; Cai, Tingting; Deng, Yang; Ding, Zhi; Liu, Yan; Zhu, Xuerui; Wang, Xin; Liu, Jie; Liang, Baowen; Zheng, Tiesong; Li, Jianlin
2018-05-02
A new aptamer microarray method on the TiO 2 -porous silicon (PSi) surface was developed to simultaneously screen multiplex mycotoxins. The TiO 2 nanolayer on the surface of PSi can enhance the fluorescence intensity 14 times than that of the thermally oxidized PSi. The aptamer fluorescence signal recovery principle was performed on the TiO 2 -PSi surface by hybridization duplex strand DNA from the mycotoxin aptamer and antiaptamer, respectively, labeled with fluorescence dye and quencher. The aptamer microarray can simultaneously screen for multiplex mycotoxins with a dynamic linear detection range of 0.1-10 ng/mL for ochratoxin A (OTA), 0.01-10 ng/mL for aflatoxins B 1 (AFB 1 ), and 0.001-10 ng/mL for fumonisin B 1 (FB 1 ) and limits of detection of 15.4, 1.48, and 0.21 pg/mL for OTA, AFB 1 , and FB 1 , respectively. The newly developed method shows good specificity and recovery rates. This method can provide a simple, sensitive, and cost-efficient platform for simultaneous screening of multiplex mycotoxins and can be easily expanded to the other aptamer-based protocol.
Hurtaud-Pessel, D; Jagadeshwar-Reddy, T; Verdon, E
2011-10-01
A liquid chromatography-high resolution mass spectrometry (LC-HRMS) method was developed for screening meat for a wide range of antibiotics used in veterinary medicine. Full-scan mode under high resolution mass spectral conditions using an LTQ-Orbitrap mass spectrometer with resolving power 60,000 full width at half maximum (FWHM) was applied for analysis of the samples. Samples were prepared using two extraction protocols prior to LC-HRMS analysis. The scope of the method focuses on screening the following main families of antibacterial veterinary drugs: penicillins, cephalosporins, sulfonamides, macrolides, tetracyclines, aminoglucosides and quinolones. Compounds were successfully identified in spiked samples from their accurate mass and LC retention times from the acquired full-scan chromatogram. Automated data processing using ToxId software allowed rapid treatment of the data. Analyses of muscle tissues from real samples collected from antibiotic-treated animals was carried out using the above methodology and antibiotic residues were identified unambiguously. Further analysis of the data for real samples allowed the identification of the targeted antibiotic residues but also non-targeted compounds, such as some of their metabolites.
Extended pseudo-screen migration with multiple reference velocities
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huang, Lian-Jie; Fehler, M.C.
1997-11-01
The pseudo-screen propagator is a kind of one way wave propagation based on the local Born approximation. The problem of the propagator is that it is difficult to calculate the scattered fields when the velocity perturbation is large; not to mention the accuracy of the propagator. We develop an extended pseudo-screen propagator by introducing different reference velocities in different regions of a medium to ensure the condition of small perturbation. The exploding reflector data for a 2D slice of the SEG/EAEG 3D salt model is generated by a finite difference scheme to test the feasibility of the method. The migrationmore » result demonstrates that the method can handle severe lateral velocity variations and provides high quality images for complex structures.« less
Parameterised post-Newtonian expansion in screened regions
NASA Astrophysics Data System (ADS)
McManus, Ryan; Lombriser, Lucas; Peñarrubia, Jorge
2017-12-01
The parameterised post-Newtonian (PPN) formalism has enabled stringent tests of static weak-field gravity in a theory-independent manner. Here we incorporate screening mechanisms of modified gravity theories into the framework by introducing an effective gravitational coupling and defining the PPN parameters as functions of position. To determine these functions we develop a general method for efficiently performing the post-Newtonian expansion in screened regimes. For illustration, we derive all the PPN functions for a cubic galileon and a chameleon model. We also analyse the Shapiro time delay effect for these two models and find no deviations from General Relativity insofar as the signal path and the perturbing mass reside in a screened region of space.
Yang, Haixia; Xiao, Lei; Wang, Nanping
2017-04-01
Peroxisome proliferator-activated receptor α (PPARα) plays a key role in lipid metabolism and glucose homeostasis and a crucial role in the prevention and treatment of metabolic diseases. Natural dietary compounds, including nutrients and phytochemicals, are PPARα ligands or modulators. High-throughput screening assays have been developed to screen for PPARα ligands and modulators in our diet. In the present review, we discuss recent advances in our knowledge of PPARα, including its structure, function, and ligand and modulator screening assays, and summarize the different types of dietary PPARα ligands and modulators. © 2016 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.
Screening for prodromal Parkinson's disease in the general community: a sleep-based approach.
Postuma, Ronald B; Pelletier, Amelie; Berg, Daniela; Gagnon, Jean-Francois; Escudier, Frédérique; Montplaisir, Jacques
2016-05-01
Neuroprotective therapy for Parkinson's disease (PD) is most likely to be effective if provided in its prodromal stages. However, identifying prodromal PD is difficult because PD is relatively uncommon, and most markers are nonspecific. Rapid eye movement (REM) sleep behavior disorder (RBD) is by far the strongest clinical marker of prodromal PD, but most patients do not seek out medical attention. Developing an efficient way of diagnosing RBD from the general community may be the most practical method to detect prodromal PD. We developed a screening strategy that began with a newspaper advertisement containing a single-question screen for RBD. All screen-positive subjects underwent an interview based on the Innsbruck RBD inventory aimed to optimize the positive predictive value. Those who passed both screens underwent confirmatory polysomnography. The proportion of screened RBD patients who met the International Parkinson and Movement Disorder Society (MDS) criteria for prodromal PD was assessed. A broad array of clinical markers of neurodegeneration was compared between newspaper-screened RBD patients and 130 RBD patients clinically referred to the sleep center. Of 111 RBD-screen-positive participants, 40 (36%) passed the secondary screen, and 29 underwent full polysomnography. Of these 29 patients, 19 were ultimately proven to have RBD (PPV = 66%), 12 (63%) of whom met the criteria for prodromal PD. Compared to patients referred to the sleep center, newspaper-screened patients had similar age, sex, olfaction, autonomic function, and color vision. However, motor and cognitive assessments were slightly better in newspaper-screened patients. A multistep screening approach using RBD screening questionnaires and telephone follow-up can efficiently identify prodromal PD in the general community. Copyright © 2016 Elsevier B.V. All rights reserved.
Pharmacophore-Map-Pick: A Method to Generate Pharmacophore Models for All Human GPCRs.
Dai, Shao-Xing; Li, Gong-Hua; Gao, Yue-Dong; Huang, Jing-Fei
2016-02-01
GPCR-based drug discovery is hindered by a lack of effective screening methods for most GPCRs that have neither ligands nor high-quality structures. With the aim to identify lead molecules for these GPCRs, we developed a new method called Pharmacophore-Map-Pick to generate pharmacophore models for all human GPCRs. The model of ADRB2 generated using this method not only predicts the binding mode of ADRB2-ligands correctly but also performs well in virtual screening. Findings also demonstrate that this method is powerful for generating high-quality pharmacophore models. The average enrichment for the pharmacophore models of the 15 targets in different GPCR families reached 15-fold at 0.5 % false-positive rate. Therefore, the pharmacophore models can be applied in virtual screening directly with no requirement for any ligand information or shape constraints. A total of 2386 pharmacophore models for 819 different GPCRs (99 % coverage (819/825)) were generated and are available at http://bsb.kiz.ac.cn/GPCRPMD. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Efficient Sporulation of Saccharomyces cerevisiae in a 96 Multiwell Format.
Paulissen, Scott M; Huang, Linda S
2016-09-17
During times of nutritional stress, Saccharomyces cerevisiae undergoes gametogenesis, known as sporulation. Diploid yeast cells that are starved for nitrogen and carbon will initiate the sporulation process. The process of sporulation includes meiosis followed by spore formation, where the haploid nuclei are packaged into environmentally resistant spores. We have developed methods for the efficient sporulation of budding yeast in 96 multiwell plates, to increase the throughput of screening yeast cells for sporulation phenotypes. These methods are compatible with screening with yeast containing plasmids requiring nutritional selection, when appropriate minimal media is used, or with screening yeast with genomic alterations, when a rich presporulation regimen is used. We find that for this method, aeration during sporulation is critical for spore formation, and have devised techniques to ensure sufficient aeration that are compatible with the 96 multiwell plate format. Although these methods do not achieve the typical ~80% level of sporulation that can be achieved in large-volume flask based experiments, these methods will reliably achieve about 50-60% level of sporulation in small-volume multiwell plates.
Development of a screening method for the determination of 49 priority pollutants in soil
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kiang, P.H.; Grob, R.L.
1986-01-01
A screening procedure was develop for the determination of 49 priority pollutants in soil. An extraction procedure followed by the capillary gas chromatographic technique was used. Dual pH solutions with methylene chloride were used as extraction solvent system; no sample clean-up procedure was applied. Both base/neutral and acid fractions were analyzed on the same capillary column (SPB-1). The relative standard deviation for 5.1 ppm (51 ..mu..g/ 10 g) concentration in zero soil was less than 25%.
In vitro methods for hazard assessment of industrial chemicals – opportunities and challenges
Wong, Chin Lin; Ghassabian, Sussan; Smith, Maree T.; Lam, Ai-Leen
2015-01-01
Allergic contact dermatitis (ACD) is a delayed-type hypersensitivity immune reaction mediated by T-lymphocytes as a result of repeated exposure of an allergen primarily on skin. ACD accounts for up to 95% of occupational skin diseases, with epoxy resins implicated as one of the most common causes of ACD. Efficient high-throughput in vitro screening for accurate identification of compounds and materials that may pose hazardous risks in the workplace is crucial. At present, the murine local lymph node assay is the ‘method of choice’ for predicting the sensitizing potency of contact allergens. As the 3Rs principles of reduction, refinement, and replacement in animal testing has gained political and economic momentum, several in vitro screening methods have been developed for identifying potential contact allergens. To date, these latter methods have been utilized primarily to assess the skin sensitizing potential of the chemical components of cosmetic products with scant research attention as to the applicability of these methods to industrial chemicals, particularly epoxy resins. Herein we review the currently utilized in vitro methods and identify the knowledge gaps with regard to assessing the generalizability of in vitro screening methods for assessing the skin sensitizing potential of industrial chemicals. PMID:25999858
In vitro methods for hazard assessment of industrial chemicals - opportunities and challenges.
Wong, Chin Lin; Ghassabian, Sussan; Smith, Maree T; Lam, Ai-Leen
2015-01-01
Allergic contact dermatitis (ACD) is a delayed-type hypersensitivity immune reaction mediated by T-lymphocytes as a result of repeated exposure of an allergen primarily on skin. ACD accounts for up to 95% of occupational skin diseases, with epoxy resins implicated as one of the most common causes of ACD. Efficient high-throughput in vitro screening for accurate identification of compounds and materials that may pose hazardous risks in the workplace is crucial. At present, the murine local lymph node assay is the 'method of choice' for predicting the sensitizing potency of contact allergens. As the 3Rs principles of reduction, refinement, and replacement in animal testing has gained political and economic momentum, several in vitro screening methods have been developed for identifying potential contact allergens. To date, these latter methods have been utilized primarily to assess the skin sensitizing potential of the chemical components of cosmetic products with scant research attention as to the applicability of these methods to industrial chemicals, particularly epoxy resins. Herein we review the currently utilized in vitro methods and identify the knowledge gaps with regard to assessing the generalizability of in vitro screening methods for assessing the skin sensitizing potential of industrial chemicals.
Geue, Claudia; Wu, Olivia; Xin, Yiqiao; Heggie, Robert; Hutchinson, Sharon; Martin, Natasha K.; Fenwick, Elisabeth; Goldberg, David
2015-01-01
Introduction Studies evaluating the cost-effectiveness of screening for Hepatitis B Virus (HBV) and Hepatitis C Virus (HCV) are generally heterogeneous in terms of risk groups, settings, screening intervention, outcomes and the economic modelling framework. It is therefore difficult to compare cost-effectiveness results between studies. This systematic review aims to summarise and critically assess existing economic models for HBV and HCV in order to identify the main methodological differences in modelling approaches. Methods A structured search strategy was developed and a systematic review carried out. A critical assessment of the decision-analytic models was carried out according to the guidelines and framework developed for assessment of decision-analytic models in Health Technology Assessment of health care interventions. Results The overall approach to analysing the cost-effectiveness of screening strategies was found to be broadly consistent for HBV and HCV. However, modelling parameters and related structure differed between models, producing different results. More recent publications performed better against a performance matrix, evaluating model components and methodology. Conclusion When assessing screening strategies for HBV and HCV infection, the focus should be on more recent studies, which applied the latest treatment regimes, test methods and had better and more complete data on which to base their models. In addition to parameter selection and associated assumptions, careful consideration of dynamic versus static modelling is recommended. Future research may want to focus on these methodological issues. In addition, the ability to evaluate screening strategies for multiple infectious diseases, (HCV and HIV at the same time) might prove important for decision makers. PMID:26689908
Developmental Screening of Refugees: A Qualitative Study
Moore, Jessica A.; Welch, Therese R.; Halterman, Jill S.; Hyman, Susan L.
2016-01-01
BACKGROUND AND OBJECTIVES: Refugee children are at high developmental risk due to dislocation and deprivation. Standardized developmental screening in this diverse population is challenging. We used the Health Belief Model to guide key-informant interviews and focus groups with medical interpreters, health care providers, community collaborators, and refugee parents to explore key elements needed for developmental screening. Cultural and community-specific values and practices related to child development and barriers and facilitators to screening were examined. METHODS: We conducted 19 interviews and 2 focus groups involving 16 Bhutanese-Nepali, Burmese, Iraqi, and Somali participants, 7 community collaborators, and 6 providers from the Center for Refugee Health in Rochester, New York. Subjects were identified through purposive sampling until data saturation. Interviews were recorded, coded, and analyzed using a qualitative framework technique. RESULTS: Twenty-one themes in 4 domains were identified: values/beliefs about development/disability, practices around development/disability, the refugee experience, and feedback specific to the Parents’ Evaluation of Developmental Status screen. Most participants denied a word for “development” in their primary language and reported limited awareness of developmental milestones. Concern was unlikely unless speech or behavior problems were present. Physical disabilities were recognized but not seen as problematic. Perceived barriers to identification of delays included limited education, poor healthcare knowledge, language, and traditional healing practices. Facilitators included community navigators, trust in health care providers, in-person interpretation, visual supports, and education about child development. CONCLUSIONS: Refugee perspectives on child development may influence a parent’s recognition of and response to developmental concerns. Despite challenges, standardized screening was supported. PMID:27527798
42 CFR 455.452 - Other State screening methods.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 42 Public Health 4 2013-10-01 2013-10-01 false Other State screening methods. 455.452 Section 455....452 Other State screening methods. Nothing in this subpart must restrict the State Medicaid agency from establishing provider screening methods in addition to or more stringent than those required by...
42 CFR 455.452 - Other State screening methods.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 42 Public Health 4 2011-10-01 2011-10-01 false Other State screening methods. 455.452 Section 455....452 Other State screening methods. Nothing in this subpart must restrict the State Medicaid agency from establishing provider screening methods in addition to or more stringent than those required by...
The U.S. EPA is developing alternative screening methods to identify putative developmental neurotoxicants and prioritize chemicals for additional testing. One method developmentally exposes zebrafish embryos and assesses nervous system structure at 2 days post-fertilization (dpf...
Wahl, Jochen; Barleon, Lorenz; Morfeld, Peter; Lichtmeß, Andrea; Haas-Brähler, Sibylle; Pfeiffer, Norbert
2016-01-01
Purpose To develop an expert system for glaucoma screening in a working population based on a human expert procedure using images of optic nerve head (ONH), visual field (frequency doubling technology, FDT) and intraocular pressure (IOP). Methods 4167 of 13037 (32%) employees between 40 and 65 years of Evonik Industries were screened. An experienced glaucoma expert (JW) assessed papilla parameters and evaluated all individual screening results. His classification into “no glaucoma”, “possible glaucoma” and “probable glaucoma” was defined as “gold standard”. A screening model was developed which was tested versus the gold-standard. This model took into account the assessment of the ONH. Values and relationships of CDR and IOP and the FDT were considered additionally and a glaucoma score was generated. The structure of the screening model was specified a priori whereas values of the parameters were chosen post-hoc to optimize sensitivity and specificity of the algorithm. Simple screening models based on IOP and / or FDT were investigated for comparison. Results 111 persons (2.66%) were classified as glaucoma suspects, thereof 13 (0.31%) as probable and 98 (2.35%) as possible glaucoma suspects by the expert. Re-evaluation by the screening model revealed a sensitivity of 83.8% and a specificity of 99.6% for all glaucoma suspects. The positive predictive value of the model was 80.2%, the negative predictive value 99.6%. Simple screening models showed insufficient diagnostic accuracy. Conclusion Adjustment of ONH and symmetry parameters with respect to excavation and IOP in an expert system produced sufficiently satisfying diagnostic accuracy. This screening model seems to be applicable in such a working population with relatively low age and low glaucoma prevalence. Different experts should validate the model in different populations. PMID:27479301
Integrated DNA walking system to characterize a broad spectrum of GMOs in food/feed matrices.
Fraiture, Marie-Alice; Herman, Philippe; Lefèvre, Loic; Taverniers, Isabel; De Loose, Marc; Deforce, Dieter; Roosens, Nancy H
2015-08-14
In order to provide a system fully integrated with qPCR screening, usually used in GMO routine analysis, as well as being able to detect, characterize and identify a broad spectrum of GMOs in food/feed matrices, two bidirectional DNA walking methods targeting p35S or tNOS, the most common transgenic elements found in GM crops, were developed. These newly developed DNA walking methods are completing the previously implemented DNA walking method targeting the t35S pCAMBIA element. Food/feed matrices containing transgenic crops (Bt rice or MON863 maize) were analysed using the integrated DNA walking system. First, the newly developed DNA walking methods, anchored on the sequences used for the p35S or tNOS qPCR screening, were tested on Bt rice that contains these two transgenic elements. Second, the methods were assessed on a maize sample containing a low amount of the GM MON863 event, representing a more complex matrix in terms of genome size and sensitivity. Finally, to illustrate its applicability in GMO routine analysis by enforcement laboratories, the entire workflow of the integrated strategy, including qPCR screening to detect the potential presence of GMOs and the subsequent DNA walking methods to characterize and identify the detected GMOs, was applied on a GeMMA Scheme Proficiency Test matrix. Via the characterization of the transgene flanking region between the transgenic cassette and the plant genome as well as of a part of the transgenic cassette, the presence of GMOs was properly confirmed or infirmed in all tested samples. Due to their simple procedure and their short time-frame to get results, the developed DNA walking methods proposed here can be easily implemented in GMO routine analysis by the enforcement laboratories. In providing crucial information about the transgene flanking regions and/or the transgenic cassettes, this DNA walking strategy is a key molecular tool to prove the presence of GMOs in any given food/feed matrix.
U.S. military enlisted accession mental health screening: history and current practice.
Cardona, Robert Andrew; Ritchie, Elspeth Cameron
2007-01-01
Through the stimulus of war and concerns about neuropsychiatric disability, the U.S. military developed methods to rapidly screen the mental health of World War I and II draftees. Intelligence testing and brief psychiatric screening expanded the accession physical examination and underwent revision to identify only gross mental health disability. Supplemental psychiatric evaluations and written psychological screening tools were abandoned after postwar assessments; they demonstrated poor predictive power in evaluating recruit service capacity for combat environments. Currently, only three mental health accession tools are used to screen applicants before their entrance into military service, namely, educational achievement, cognitive testing, and a cursory psychiatric evaluation. The Navy and Air Force use a fourth screening measure during entry-level training. Educational attainment with high school graduation has been the strongest predictor of finishing a service term. The purpose of this article is to provide both a historical review and a review of testing efforts.
Goryacheva, Irina Yu; De Saeger, Sarah; Nesterenko, Irina S; Eremin, Sergei A; Van Peteghem, Carlos
2007-05-15
A feasible three-step method for ochratoxin A (OTA) rapid detection was developed and applied for OTA screening in high-coloured matrices such as liquorice, ginger, nutmeg, black pepper, white pepper and Capsicum spp. spices at a control level of 10mugkg(-1). The method was based on the clean-up tandem immunoassay column and involved three steps: extract application, washing step and application of chromogenic substrate. A significant simplification of the assay was reached by using an additional frit with conjugate inside the clean-up tandem immunoassay column. The time for analysis was less than 10min, including 5min for colour development. Results were visually evaluated as colour development for negative result or no colour development for positive result. The method was coupled with a simple methanol-based extraction. A total of 27 samples were screened for OTA with the proposed method. It was shown that two samples of red pepper and one sample of liquorice, pili-pili, chilli and cayenne were contaminated with OTA above the control level at 10mugkg(-1), but none of tested ginger, nutmeg, black pepper and white pepper.
Micro Dot Patterning on the Light Guide Panel Using Powder Blasting
Jang, Ho Su; Cho, Myeong Woo; Park, Dong Sam
2008-01-01
This study is to develop a micromachining technology for a light guide panel(LGP) mold, whereby micro dot patterns are formed on a LGP surface by a single injection process instead of existing screen printing processes. The micro powder blasting technique is applied to form micro dot patterns on the LGP mold surface. The optimal conditions for masking, laminating, exposure, and developing processes to form the micro dot patterns are first experimentally investigated. A LGP mold with masked micro patterns is then machined using the micro powder blasting method and the machinability of the micro dot patterns is verified. A prototype LGP is test- injected using the developed LGP mold and a shape analysis of the patterns and performance testing of the injected LGP are carried out. As an additional approach, matte finishing, a special surface treatment method, is applied to the mold surface to improve the light diffusion characteristics, uniformity and brightness of the LGP. The results of this study show that the applied powder blasting method can be successfully used to manufacture LGPs with micro patterns by just single injection using the developed mold and thereby replace existing screen printing methods. PMID:27879740
Genome-wide RNAi Screening to Identify Host Factors That Modulate Oncolytic Virus Therapy.
Allan, Kristina J; Mahoney, Douglas J; Baird, Stephen D; Lefebvre, Charles A; Stojdl, David F
2018-04-03
High-throughput genome-wide RNAi (RNA interference) screening technology has been widely used for discovering host factors that impact virus replication. Here we present the application of this technology to uncovering host targets that specifically modulate the replication of Maraba virus, an oncolytic rhabdovirus, and vaccinia virus with the goal of enhancing therapy. While the protocol has been tested for use with oncolytic Maraba virus and oncolytic vaccinia virus, this approach is applicable to other oncolytic viruses and can also be utilized for identifying host targets that modulate virus replication in mammalian cells in general. This protocol describes the development and validation of an assay for high-throughput RNAi screening in mammalian cells, the key considerations and preparation steps important for conducting a primary high-throughput RNAi screen, and a step-by-step guide for conducting a primary high-throughput RNAi screen; in addition, it broadly outlines the methods for conducting secondary screen validation and tertiary validation studies. The benefit of high-throughput RNAi screening is that it allows one to catalogue, in an extensive and unbiased fashion, host factors that modulate any aspect of virus replication for which one can develop an in vitro assay such as infectivity, burst size, and cytotoxicity. It has the power to uncover biotherapeutic targets unforeseen based on current knowledge.
Grohmann, Lutz; Brünen-Nieweler, Claudia; Nemeth, Anne; Waiblinger, Hans-Ulrich
2009-10-14
Polymerase Chain Reaction (PCR)-based screening methods targeting genetic elements commonly used in genetically modified (GM) plants are important tools for the detection of GM materials in food, feed, and seed samples. To expand and harmonize the screening capability of enforcement laboratories, the German Federal Office of Consumer Protection and Food Safety conducted collaborative trials for interlaboratory validation of real-time PCR methods for detection of the phosphinothricin acetyltransferase (bar) gene from Streptomyces hygroscopicus and a construct containing the 5-enolpyruvylshikimate-3-phosphate synthase gene from Agrobacterium tumefaciens sp. strain CP4 (ctp2-cp4epsps), respectively. To assess the limit of detection, precision, and accuracy of the methods, laboratories had to analyze two sets of 18 coded genomic DNA samples of events LLRice62 and MS8 with the bar method and NK603 and GT73 with the ctp2-cp4epsps method at analyte levels of 0, 0.02, and 0.1% GM content, respectively. In addition, standard DNAs were provided to the laboratories to generate calibration curves for copy number quantification of the bar and ctp2-cp4epsps target sequences present in the test samples. The study design and the results obtained are discussed with respect to the difficult issue of developing general guidelines and concepts for the collaborative trial validation of qualitative PCR screening methods.
Micro Dot Patterning on the Light Guide Panel Using Powder Blasting.
Jang, Ho Su; Cho, Myeong Woo; Park, Dong Sam
2008-02-08
This study is to develop a micromachining technology for a light guidepanel(LGP) mold, whereby micro dot patterns are formed on a LGP surface by a singleinjection process instead of existing screen printing processes. The micro powder blastingtechnique is applied to form micro dot patterns on the LGP mold surface. The optimalconditions for masking, laminating, exposure, and developing processes to form the microdot patterns are first experimentally investigated. A LGP mold with masked micro patternsis then machined using the micro powder blasting method and the machinability of themicro dot patterns is verified. A prototype LGP is test- injected using the developed LGPmold and a shape analysis of the patterns and performance testing of the injected LGP arecarried out. As an additional approach, matte finishing, a special surface treatment method,is applied to the mold surface to improve the light diffusion characteristics, uniformity andbrightness of the LGP. The results of this study show that the applied powder blastingmethod can be successfully used to manufacture LGPs with micro patterns by just singleinjection using the developed mold and thereby replace existing screen printing methods.
Peng, Cheng; Wang, Hua; Xu, Xiaoli; Wang, Xiaofu; Chen, Xiaoyun; Wei, Wei; Lai, Yongmin; Liu, Guoquan; Godwin, Ian Douglas; Li, Jieqin; Zhang, Ling; Xu, Junfeng
2018-05-15
Gene editing techniques are becoming powerful tools for modifying target genes in organisms. Although several methods have been developed to detect gene-edited organisms, these techniques are time and labour intensive. Meanwhile, few studies have investigated high-throughput detection and screening strategies for plants modified by gene editing. In this study, we developed a simple, sensitive and high-throughput quantitative real-time (qPCR)-based method. The qPCR-based method exploits two differently labelled probes that are placed within one amplicon at the gene editing target site to simultaneously detect the wild-type and a gene-edited mutant. We showed that the qPCR-based method can accurately distinguish CRISPR/Cas9-induced mutants from the wild-type in several different plant species, such as Oryza sativa, Arabidopsis thaliana, Sorghum bicolor, and Zea mays. Moreover, the method can subsequently determine the mutation type by direct sequencing of the qPCR products of mutations due to gene editing. The qPCR-based method is also sufficiently sensitive to distinguish between heterozygous and homozygous mutations in T 0 transgenic plants. In a 384-well plate format, the method enabled the simultaneous analysis of up to 128 samples in three replicates without handling the post-polymerase chain reaction (PCR) products. Thus, we propose that our method is an ideal choice for screening plants modified by gene editing from many candidates in T 0 transgenic plants, which will be widely used in the area of plant gene editing. © 2018 The Authors The Plant Journal © 2018 John Wiley & Sons Ltd.
Shin, Jeong-Sook; Peng, Lei; Kang, Kyungsu; Choi, Yongsoo
2016-09-09
Direct analysis of prostaglandin-E2 (PGE2) and -D2 (PGD2) produced from a RAW264.7 cell-based reaction was performed by liquid chromatography high-resolution mass spectrometry (LC-HRMS), which was online coupled with turbulent flow chromatography (TFC). The capability of this method to accurately measure PG levels in cell reaction medium containing cytokines or proteins as a reaction byproduct was cross-validated by two conventional methods. Two methods, including an LC-HRMS method after liquid-liquid extraction (LLE) of the sample and a commercial PGE2 enzyme-linked immunosorbent assay (ELISA), showed PGE2 and/or PGD2 levels almost similar to those obtained by TFC LC-HRMS over the reaction time after LPS stimulation. After the cross-validation, significant analytical throughputs, allowing simultaneous screening and potency evaluation of 80 natural products including 60 phytochemicals and 20 natural product extracts for the inhibition of the PGD2 produced in the cell-based inflammatory reaction, were achieved using the TFC LC-HRMS method developed. Among the 60 phytochemicals screened, licochalcone A and formononetin inhibited PGD2 production the most with IC50 values of 126 and 151nM, respectively. For a reference activity, indomethacin and diclofenac were used, measuring IC50 values of 0.64 and 0.21nM, respectively. This method also found a butanol extract of Akebia quinata Decne (AQ) stem as a promising natural product for PGD2 inhibition. Direct and accurate analysis of PGs in the inflammatory cell reaction using the TFC LC-HRMS method developed enables the high-throughput screening and potency evaluation of as many as 320 samples in less than 48h without changing a TFC column. Copyright © 2016 Elsevier B.V. All rights reserved.
Adamowicz, Piotr; Tokarczyk, Bogdan
2016-07-01
In recent years, many new psychoactive substances (NPS) from several drug classes have appeared on the drug market. These substances, also known as 'legal highs', belong to different chemical classes. Despite the increasing number of NPS, there are few comprehensive screening methods for their detection in biological specimens. In this context, the purpose of this study was to develop a fast and simple liquid chromatography-tandem mass spectrometry (LC-MS/MS) screening procedure for NPS in blood. The elaborated method allows the simultaneous screening of 143 compounds from different groups (number of compounds): cathinones (36), phenethylamines (26), tryptamines (18), piperazines (9), piperidines (2), synthetic cannabinoids (34), arylalkylamines (7), arylcyclohexylamines (3), aminoindanes (2), and other drugs (6). Blood samples (0.2 mL) were precipitated with acetonitrile (0.6 mL). The separation was achieved with gradient mobile phase of 0.1% formic acid in acetonitrile and 0.1% formic acid in water in 14 min. Detection of all compounds was based on multiple reaction monitoring (MRM) transitions. The total number of transitions monitored in dynamic mode was 432. The whole procedure was rapid and simple. The limits of detection (LODs) estimated for 104 compounds were in the range 0.01-3.09 ng/mL. The extraction recoveries determined for 32 compounds were from 1.8 to 133%. The procedure was successfully applied to the analysis of forensic blood samples in routine casework. The developed method should have wide applicability for rapid screening of new drugs of abuse in forensic or clinical samples. The procedure can be easily expanded for more substances. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.
Serpe, F P; Russo, R; Ambrosio, L; Esposito, M; Severino, L
2013-06-01
European Commission Regulation 882/2004/EC requires that official control laboratories for foodstuffs in the member states are certified according to UNI EN ISO/IEC 17025:2005 (general requirement for the competence of calibration and testing laboratories). This mandatory requirement has resulted in a continuous adaptation and development of analytical procedures. The aim of this study was to develop a method for semiquantitative screening of polychlorinated biphenyls in fish for human consumption. According to the Commission Decision 657/2002/CE, the detection capability, the precision, the selectivity-specificity, and applicability-ruggedness-stability were determined to validate the method. Moreover, trueness was verified. This procedure resulted in rapid execution, which allowed immediate and effective intervention by the local health authorities to protect the health of consumers. Finally, the procedure has been recognized by the Italian accrediting body, ACCREDIA.
The U.S. EPA, under its ExpoCast program, is developing high-throughput near-field modeling methods to estimate human chemical exposure and to provide real-world context to high-throughput screening (HTS) hazard data. These novel modeling methods include reverse methods to infer ...
The interdependence between screening methods and screening libraries.
Shelat, Anang A; Guy, R Kiplin
2007-06-01
The most common methods for discovery of chemical compounds capable of manipulating biological function involves some form of screening. The success of such screens is highly dependent on the chemical materials - commonly referred to as libraries - that are assayed. Classic methods for the design of screening libraries have depended on knowledge of target structure and relevant pharmacophores for target focus, and on simple count-based measures to assess other properties. The recent proliferation of two novel screening paradigms, structure-based screening and high-content screening, prompts a profound rethink about the ideal composition of small-molecule screening libraries. We suggest that currently utilized libraries are not optimal for addressing new targets by high-throughput screening, or complex phenotypes by high-content screening.
Peirson, Leslea; Catallo, Cristina; Chera, Sunita
2013-08-01
This paper examines the development of a globally accessible online Registry of Knowledge Translation Methods and Tools to support evidence-informed public health. A search strategy, screening and data extraction tools, and writing template were developed to find, assess, and summarize relevant methods and tools. An interactive website and searchable database were designed to house the registry. Formative evaluation was undertaken to inform refinements. Over 43,000 citations were screened; almost 700 were full-text reviewed, 140 of which were included. By November 2012, 133 summaries were available. Between January 1 and November 30, 2012 over 32,945 visitors from more than 190 countries accessed the registry. Results from 286 surveys and 19 interviews indicated the registry is valued and useful, but would benefit from a more intuitive indexing system and refinements to the summaries. User stories and promotional activities help expand the reach and uptake of knowledge translation methods and tools in public health contexts. The National Collaborating Centre for Methods and Tools' Registry of Methods and Tools is a unique and practical resource for public health decision makers worldwide.
[Progresses in screening active compounds from herbal medicine by affinity chromatography].
Feng, Ying-shu; Tong, Shan-shan; Xu, Xi-ming; Yu, Jiang-nan
2015-03-01
Affinity chromatography is a chromatographic method for separating molecules using the binding characteristics of the stationary phase with potential drug molecules. This method can be performed as a high throughput screening method and a chromatographic separation method to screen a variety of active drugs. This paper summarizes the history of affinity chromatography, screening technology of affinity chromatography, and application of affinity chromatography in screening bio-active compounds in herbal medicines, and then discusses its application prospects, in order to broaden applications of the affinity chromatography in drug screening.
Zaffanello, Marco; Rugolotto, Simone; Zamboni, Giorgio; Gaudino, Rossella; Tatò, Luciano
2004-01-01
We examined glucose-6-phosphate dehydrogenase (G6PD) deficiency in north-eastern Italian Caucasian neonates detected by neonatal screening, in order to measure the incidence of heterozygote females detected by neonatal screening, and to estimate the near-true total incidence. A total of 85,437 Caucasian neonates, born between January 2000 and December 2001, have been enclosed in the study. The total incidence of the disease, measured by fluorescent method, is 0.9 per thousand; the total incidence, calculated by Hardy-Weinberg law, is 4.8 per thousand. The frequency of missed females is 93% of total females expected with G6PD deficiency; most of them are very likely heterozygous females. The sensitivity of the fluorescent method might be not sufficient to detect all females. Since heterozygote females might develop the symptoms of G6PD deficiency later, these results suggest that the G6PD neonatal screening may not be helpful in preventing disease in females.
Zhao, Ben; Li, Yafei; Li, Changling; Yang, Hailin; Wang, Wu
2018-03-01
Schizochytrium sp. accumulates valuable polyunsaturated fatty acid (PUFA), such as docosahexaenoic acid (DHA). In order to increase DHA synthesis in this microorganism, physical or chemical mutagenesis aided with powerful screening methods are still preferable, as its DHA synthetic pathway has not yet been clearly defined for gene manipulation. To breed this agglomerate microorganism of thick cell wall and rather large genome for increasing lipid content and DHA percentage, a novel strategy of atmospheric and room temperature plasma (ARTP) mutagenesis coupled with stepped malonic acid (MA) and zeocin resistance screening was developed. The final resulted mutant strain mz-17 was selected with 1.8-fold increased DHA production. Accompanied with supplementation of Fe 2+ in shake flask cultivation, DHA production of 14.0 g/L on average was achieved. This work suggests that ARTP mutation combined with stepped MA and zeocin resistance screening is an efficient method of breeding Schizochytrium sp. of high DHA production, and might be applied on other microorganisms for obtaining higher desired PUFA products.
Mamon, J; Green, L; Levine, D M; Gibson, G; Gurley, H T
1987-08-01
This study describes the development and testing of a high blood pressure protocol for use in emergency departments (ED) to enhance detection of those patients appropriate for subsequent referral. The protocol involves two serial blood pressure measurements and a patient interview to determine: 1) previous history of high blood pressure (HBP), 2) treatment in past year for HBP, and 3) usual source of medical care. The accuracy of patient reporting was validated by comparison with the patients' hospital record (reflecting outpatient and inpatient visits). Results indicate that these self-reports have high levels of sensitivity (range 90-100%) and specificity (range 79-96%). Use of the additional patient information increased the sensitivity of the screening protocol in identifying when and where a patient should be referred. Use of this methodology indicates that the protocol is a simple and effective method for HBP screening. The findings also suggest that the ED is an ideal site for screening the "hard-to-reach" hypertensive population.
Thulien, Naomi S
2014-03-01
Female sex trade workers are among those at highest risk for developing and dying of cervical cancer, and yet many-particularly the most marginalized-are less likely than other women to be screened. This review summarizes global findings on innovative approaches to cervical cancer screening for female sex trade workers, highlights current gaps in the delivery of cervical cancer screening for female sex trade workers globally, and suggests areas for future research and policy development. A scoping review of peer-reviewed publications and grey literature was conducted. Medline (OVID), PubMed, EMBASE, and SCOPUS were searched for relevant studies written in English. There were no limitations placed on dates. Grey literature was identified by hand searching and through discussion with health care providers and community outreach workers currently working with sex trade workers. Twenty-five articles were deemed suitable for review. Articles detailing innovative ways for female sex trade workers to access cervical cancer screening were included. Articles about screening for sexually transmitted infections were also included if the findings could be generalized to screening for cervical cancer. Articles limited to exploring risk factors, knowledge, awareness, education, prevalence, and incidence of cervical cancer among sex trade workers were excluded from the review. Successful screening initiatives identified in the studies reviewed had unconventional hours of operation, understood the difference between street-based and venue-based sex trade workers, and/or used peers for outreach. Two significant gaps in health care service delivery were highlighted in this review: the limited use of unorthodox hours and the nearly exclusive practice of providing sexually transmitted infection screening for female sex trade workers without cervical cancer screening. In addition, although street-based (as opposed to venue-based) sex trade workers are likely at higher risk for developing cervical cancer, they are much less likely than other eligible women to participate in screening programs, meaning traditional outreach methods are unlikely to be successful.
NASA Astrophysics Data System (ADS)
Rush, Michael D.; Walker, Elisabeth M.; Prehna, Gerd; Burton, Tristesse; van Breemen, Richard B.
2017-03-01
To overcome limiting factors in mass spectrometry-based screening methods such as automation while still facilitating the screening of complex mixtures such as botanical extracts, magnetic microbead affinity selection screening (MagMASS) was developed. The screening process involves immobilization of a target protein on a magnetic microbead using a variety of possible chemistries, incubation with mixtures of molecules containing possible ligands, a washing step that removes non-bound compounds while a magnetic field retains the beads in the microtiter well, and an organic solvent release step followed by LC-MS analysis. Using retinoid X receptor-α (RXRα) as an example, which is a nuclear receptor and target for anti-inflammation therapy as well as cancer treatment and prevention, a MagMASS assay was developed and compared with an existing screening assay, pulsed ultrafiltration (PUF)-MS. Optimization of MagMASS involved evaluation of multiple protein constructs and several magnetic bead immobilization chemistries. The full-length RXRα construct immobilized with amylose beads provided optimum results. Additional enhancements of MagMASS were the application of 96-well plates to enable automation, use of UHPLC instead of HPLC for faster MS analyses, and application of metabolomics software for faster, automated data analysis. Performance of MagMASS was demonstrated using mixtures of synthetic compounds and known ligands spiked into botanical extracts.
Probe Heating Method for the Analysis of Solid Samples Using a Portable Mass Spectrometer
Kumano, Shun; Sugiyama, Masuyuki; Yamada, Masuyoshi; Nishimura, Kazushige; Hasegawa, Hideki; Morokuma, Hidetoshi; Inoue, Hiroyuki; Hashimoto, Yuichiro
2015-01-01
We previously reported on the development of a portable mass spectrometer for the onsite screening of illicit drugs, but our previous sampling system could only be used for liquid samples. In this study, we report on an attempt to develop a probe heating method that also permits solid samples to be analyzed using a portable mass spectrometer. An aluminum rod is used as the sampling probe. The powdered sample is affixed to the sampling probe or a droplet of sample solution is placed on the tip of the probe and dried. The probe is then placed on a heater to vaporize the sample. The vapor is then introduced into the portable mass spectrometer and analyzed. With the heater temperature set to 130°C, the developed system detected 1 ng of methamphetamine, 1 ng of amphetamine, 3 ng of 3,4-methylenedioxymethamphetamine, 1 ng of 3,4-methylenedioxyamphetamine, and 0.3 ng of cocaine. Even from mixtures consisting of clove powder and methamphetamine powder, methamphetamine ions were detected by tandem mass spectrometry. The developed probe heating method provides a simple method for the analysis of solid samples. A portable mass spectrometer incorporating this method would thus be useful for the onsite screening of illicit drugs. PMID:26819909
Shao, Jingyuan; Cao, Wen; Qu, Haibin; Pan, Jianyang; Gong, Xingchu
2018-01-01
The aim of this study was to present a novel analytical quality by design (AQbD) approach for developing an HPLC method to analyze herbal extracts. In this approach, critical method attributes (CMAs) and critical method parameters (CMPs) of the analytical method were determined using the same data collected from screening experiments. The HPLC-ELSD method for separation and quantification of sugars in Codonopsis Radix extract (CRE) samples and Astragali Radix extract (ARE) samples was developed as an example method with a novel AQbD approach. Potential CMAs and potential CMPs were found with Analytical Target Profile. After the screening experiments, the retention time of the D-glucose peak of CRE samples, the signal-to-noise ratio of the D-glucose peak of CRE samples, and retention time of the sucrose peak in ARE samples were considered CMAs. The initial and final composition of the mobile phase, flow rate, and column temperature were found to be CMPs using a standard partial regression coefficient method. The probability-based design space was calculated using a Monte-Carlo simulation method and verified by experiments. The optimized method was validated to be accurate and precise, and then it was applied in the analysis of CRE and ARE samples. The present AQbD approach is efficient and suitable for analysis objects with complex compositions.
Tai, Mitchell; Ly, Amanda; Leung, Inne; Nayar, Gautam
2015-01-01
The burgeoning pipeline for new biologic drugs has increased the need for high-throughput process characterization to efficiently use process development resources. Breakthroughs in highly automated and parallelized upstream process development have led to technologies such as the 250-mL automated mini bioreactor (ambr250™) system. Furthermore, developments in modern design of experiments (DoE) have promoted the use of definitive screening design (DSD) as an efficient method to combine factor screening and characterization. Here we utilize the 24-bioreactor ambr250™ system with 10-factor DSD to demonstrate a systematic experimental workflow to efficiently characterize an Escherichia coli (E. coli) fermentation process for recombinant protein production. The generated process model is further validated by laboratory-scale experiments and shows how the strategy is useful for quality by design (QbD) approaches to control strategies for late-stage characterization. © 2015 American Institute of Chemical Engineers.
Screening of Compounds Toxicity against Human Monocytic cell line-THP-1 by Flow Cytometry
Pick, Neora; Cameron, Scott; Arad, Dorit
2004-01-01
The worldwide rapid increase in bacterial resistance to numerous antibiotics requires on-going development of new drugs to enter the market. As the development of new antibiotics is lengthy and costly, early monitoring of compound's toxicity is essential in the development of novel agents. Our interest is in a rapid, simple, high throughput screening method to assess cytotoxicity induced by potential agents. Some intracellular pathogens, such as Mycobacterium tuberculosis primary site of infection is human alveolar macrophages. Thus, evaluation of candidate drugs for macrophage toxicity is crucial. Protocols for high throughput drug toxicity screening of macrophages using flow cytometry are lacking in the literature. For this application we modified a preexisting technique, propidium iodide (PI) exclusion staining and utilized it for rapid toxicity tests. Samples were prepared in 96 well plates and analyzed by flow cytometry, which allowed for rapid, inexpensive and precise assessment of compound's toxicity associated with cell death. PMID:15472722
Fitzpatrick, Shaun; Taylor, Scott; Booth, Steven W; Newton, Michael J
2006-01-01
A development program has been carried out to provide a stable extrusion/spheronisation pellet formulation for a highly water-soluble drug, sitagliptin, which undergoes a change in physical form on processing and is subject to hydrolytic decomposition. A conventional extrusion/spheronization formulation resulted in significant degradation of the drug. The inclusion of glyceryl monostearate into the formulation was found to reduce the water levels required to such a level that there was no significant degradation of the drug during processing to form pellets. The use of a ram extruder to screen formulations with small quantities minimizes the need for the drug in the formulation-screening process, and the results from this method of extrusion were found to be translatable to the use of a screen extruder, which allowed scale-up of the process.
Suflita, Joseph M.; Concannon, Frank
1995-01-01
Screening methods were developed to assess the susceptibility of ground water contaminants to anaerobic biodegradation. One method was an extrapolation of a procedure previously used to measure biodegradation activity in dilute sewage sludge. Aquifer solids and ground water with no additional nutritive media were incubated anaerobically in 160-ml serum bottles containing 250 mg·l−1 carbon of the substrate of interest. This method relied on the detection of gas pressure or methane production in substrateamended microcosms relative to background controls. Other screening procedures involved the consumption of stoichiometrically required amounts of sulfate or nitrate from the same type of incubations. Close agreement was obtained between the measured and calculated amounts of substrate bioconversion based on the measured biogas pressure in methanogenic microcosms. Storage of the microcosms for up to 6 months did not adversely influence the onset or rate of benzoic acid mineralization. The lower detection limits of the methanogenic assay were found to be a function of the size of the microcosm headspace, the mean oxidation state of the substrate carbon, and the method used to correct for background temperature fluctuations. Using these simple screening procedures, biodegradation information of regulatory interest could be generated, including, (i) the length of the adaptation period, (ii) the rate of substrate decay and (iii) the completeness of the bioconversion.
FAITH – Fast Assembly Inhibitor Test for HIV
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hadravová, Romana; Rumlová, Michaela, E-mail: michaela.rumlova@vscht.cz; Department of Biotechnology, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague
Due to the high number of drug-resistant HIV-1 mutants generated by highly active antiretroviral therapy (HAART), there is continuing demand for new types of inhibitors. Both the assembly of the Gag polyprotein into immature and mature HIV-1 particles are attractive candidates for the blocking of the retroviral life cycle. Currently, no therapeutically-used assembly inhibitor is available. One possible explanation is the lack of a reliable and simple assembly inhibitor screening method. To identify compounds potentially inhibiting the formation of both types of HIV-1 particles, we developed a new fluorescent high-throughput screening assay. This assay is based on the quantification ofmore » the assembly efficiency in vitro in a 96-well plate format. The key components of the assay are HIV-1 Gag-derived proteins and a dual-labelled oligonucleotide, which emits fluorescence only when the assembly of retroviral particles is inhibited. The method was validated using three (CAI, BM2, PF74) reported assembly inhibitors. - Highlights: • Allows screening of assembly inhibitors of both mature and immature HIV-1 particles. • Based on Gag-derived proteins with CA in mature or immature conformation. • Simple and sensitive method suitable for high-throughput screening of inhibitors. • Unlike in other HIV assembly methods, works under physiological conditions. • No washing steps are necessary.« less
Wang, Ting; Li, Weiying; Zheng, Xiaofeng; Lin, Zhifen; Kong, Deyang
2014-02-01
During the last past decades, there is an increasing number of studies about estrogenic activities of the environmental pollutants on amphibians and many determination methods have been proposed. However, these determination methods are time-consuming and expensive, and a rapid and simple method to screen and test the chemicals for estrogenic activities to amphibians is therefore imperative. Herein is proposed a new decision tree formulated not only with physicochemical parameters but also a biological parameter that was successfully used to screen estrogenic activities of the chemicals on amphibians. The biological parameter, CDOCKER interaction energy (Ebinding ) between chemicals and the target proteins was calculated based on the method of molecular docking, and it was used to revise the decision tree formulated by Hong only with physicochemical parameters for screening estrogenic activity of chemicals in rat. According to the correlation between Ebinding of rat and Xenopus laevis, a new decision tree for estrogenic activities in Xenopus laevis is finally proposed. Then it was validated by using the randomly 8 chemicals which can be frequently exposed to Xenopus laevis, and the agreement between the results from the new decision tree and the ones from experiments is generally satisfactory. Consequently, the new decision tree can be used to screen the estrogenic activities of the chemicals, and combinational use of the Ebinding and classical physicochemical parameters can greatly improves Hong's decision tree. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Rapid screening method for male DNA by using the loop-mediated isothermal amplification assay.
Kitamura, Masashi; Kubo, Seiji; Tanaka, Jin; Adachi, Tatsushi
2017-08-12
Screening for male-derived biological material from collected samples plays an important role in criminal investigations, especially those involving sexual assaults. We have developed a loop-mediated isothermal amplification (LAMP) assay targeting multi-repeat sequences of the Y chromosome for detecting male DNA. Successful amplification occurred with 0.5 ng of male DNA under isothermal conditions of 61 to 67 °C, but no amplification occurred with up to 10 ng of female DNA. Under the optimized conditions, the LAMP reaction initiated amplification within 10 min and amplified for 20 min. The LAMP reaction was sensitive at levels as low as 1-pg male DNA, and a quantitative LAMP assay could be developed because of the strong correlation between the reaction time and the amount of template DNA in the range of 10 pg to 10 ng. Furthermore, to apply the LAMP assay to on-site screening for male-derived samples, we evaluated a protocol using a simple DNA extraction method and a colorimetric intercalating dye that allows detection of the LAMP reaction by evaluating the change in color of the solution. Using this protocol, samples of male-derived blood and saliva stains were processed in approximately 30 min from DNA extraction to detection. Because our protocol does not require much hands-on time or special equipment, this LAMP assay promises to become a rapid and simple screening method for male-derived samples in forensic investigations.
Nir, Oaz; Bakal, Chris; Perrimon, Norbert; Berger, Bonnie
2010-03-01
Biological networks are highly complex systems, consisting largely of enzymes that act as molecular switches to activate/inhibit downstream targets via post-translational modification. Computational techniques have been developed to perform signaling network inference using some high-throughput data sources, such as those generated from transcriptional and proteomic studies, but comparable methods have not been developed to use high-content morphological data, which are emerging principally from large-scale RNAi screens, to these ends. Here, we describe a systematic computational framework based on a classification model for identifying genetic interactions using high-dimensional single-cell morphological data from genetic screens, apply it to RhoGAP/GTPase regulation in Drosophila, and evaluate its efficacy. Augmented by knowledge of the basic structure of RhoGAP/GTPase signaling, namely, that GAPs act directly upstream of GTPases, we apply our framework for identifying genetic interactions to predict signaling relationships between these proteins. We find that our method makes mediocre predictions using only RhoGAP single-knockdown morphological data, yet achieves vastly improved accuracy by including original data from a double-knockdown RhoGAP genetic screen, which likely reflects the redundant network structure of RhoGAP/GTPase signaling. We consider other possible methods for inference and show that our primary model outperforms the alternatives. This work demonstrates the fundamental fact that high-throughput morphological data can be used in a systematic, successful fashion to identify genetic interactions and, using additional elementary knowledge of network structure, to infer signaling relations.
Screening and assessment tools for pediatric malnutrition.
Huysentruyt, Koen; Vandenplas, Yvan; De Schepper, Jean
2016-06-18
The ideal measures for screening and assessing undernutrition in children remain a point of discussion in literature. This review aims to provide an overview of recent advances in the nutritional screening and assessment methods in children. This review focuses on two major topics that emerged in literature since 2015: the practical endorsement of the new definition for pediatric undernutrition, with a focus on anthropometric measurements and the search for a consensus on pediatric nutritional screening tools in different settings. Few analytical tools exist for the assessment of the nutritional status in children. The subjective global nutritional assessment has been validated by anthropometric as well as clinical outcome parameters. Nutritional screening can help in selecting patients that benefit the most from a full nutritional assessment. Two new screening tools have been developed for use in a general (mixed) hospital population, and one for a population of children with cancer. The value of screening tools in different disease-specific and outpatient pediatric populations remains to be proven.
Tang, F; Xiong, Y; Zhang, H; Wu, K; Xiang, Y; Shao, J-B; Ai, H-W; Xiang, Y-P; Zheng, X-L; Lv, J-R; Sun, H; Bao, L-S; Zhang, Z; Hu, H-B; Zhang, J-Y; Chen, L; Lu, J; Liu, W-Y; Mei, H; Ma, Y; Xu, C-F; Fang, A-Y; Gu, M; Xu, C-Y; Chen, Y; Chen, Z; Sun, Z-Y
2016-03-01
To detect Salmonella more efficiently and isolate strains more easily, a novel and simple detection method that uses an enrichment assay and two chromogenic reactions on a chromatography membrane was developed. Grade 3 chromatography paper is used as functionalized solid phase support (SPS), which contains specially optimized medium. One reaction for screening is based on the sulfate-reducing capacity of Salmonella. Hydrogen sulfide (H2S) generated by Salmonella reacts with ammonium ferric citrate to produce black colored ferrous sulfide. Another reaction is based on Salmonella C8 esterase that is unique for Enterobacteriaceae except Serratia and interacts with 4-methylumbelliferyl caprylate (MUCAP) to produce fluorescent umbelliferone, which is visible under ultraviolet light. A very low detection limit (10(1) CFU ml(-1)) for Salmonella was achieved on the background of 10(5) CFU ml(-1) Escherichia coli. More importantly, testing with more than 1,000 anal samples indicated that our method has a high positive detection rate and is relatively low cost, compared with the traditional culture-based method. It took only 1 day for the preliminary screening and 2 days to efficiently isolate the Salmonella cells, indicating that the new assay is specific, rapid, and simple for Salmonella detection. In contrast to the traditional culture-based method, this method can be easily used to screen and isolate targeted strains with the naked eye. The results of quantitative and comparative experiments showed that the visual detection technique is an efficient alternative method for the screening of Salmonella spp. in many applications of large-sized samples related to public health surveillance.
NASA Astrophysics Data System (ADS)
Nieuwoudt, Michel K.; Holroyd, Steve E.; McGoverin, Cushla M.; Simpson, M. Cather; Williams, David E.
2017-02-01
Point-of-care diagnostics are of interest in the medical, security and food industry, the latter particularly for screening food adulterated for economic gain. Milk adulteration continues to be a major problem worldwide and different methods to detect fraudulent additives have been investigated for over a century. Laboratory based methods are limited in their application to point-of-collection diagnosis and also require expensive instrumentation, chemicals and skilled technicians. This has encouraged exploration of spectroscopic methods as more rapid and inexpensive alternatives. Raman spectroscopy has excellent potential for screening of milk because of the rich complexity inherent in its signals. The rapid advances in photonic technologies and fabrication methods are enabling increasingly sensitive portable mini-Raman systems to be placed on the market that are both affordable and feasible for both point-of-care and point-of-collection applications. We have developed a powerful spectroscopic method for rapidly screening liquid milk for sucrose and four nitrogen-rich adulterants (dicyandiamide (DCD), ammonium sulphate, melamine, urea), using a combined system: a small, portable Raman spectrometer with focusing fibre optic probe and optimized reflective focusing wells, simply fabricated in aluminium. The reliable sample presentation of this system enabled high reproducibility of 8% RSD (residual standard deviation) within four minutes. Limit of detection intervals for PLS calibrations ranged between 140 - 520 ppm for the four N-rich compounds and between 0.7 - 3.6 % for sucrose. The portability of the system and reliability and reproducibility of this technique opens opportunities for general, reagentless adulteration screening of biological fluids as well as milk, at point-of-collection.
A set of three complementary analytical methods were developed specifically for exhaled breath as collected in evacuated stainless steel canisters using gas chromatography - mass spectrometry detection. The first is a screening method to quantify the carbon dioxide component (gen...
Smith, Alec S T; Macadangdang, Jesse; Leung, Winnie; Laflamme, Michael A; Kim, Deok-Ho
Improved methodologies for modeling cardiac disease phenotypes and accurately screening the efficacy and toxicity of potential therapeutic compounds are actively being sought to advance drug development and improve disease modeling capabilities. To that end, much recent effort has been devoted to the development of novel engineered biomimetic cardiac tissue platforms that accurately recapitulate the structure and function of the human myocardium. Within the field of cardiac engineering, induced pluripotent stem cells (iPSCs) are an exciting tool that offer the potential to advance the current state of the art, as they are derived from somatic cells, enabling the development of personalized medical strategies and patient specific disease models. Here we review different aspects of iPSC-based cardiac engineering technologies. We highlight methods for producing iPSC-derived cardiomyocytes (iPSC-CMs) and discuss their application to compound efficacy/toxicity screening and in vitro modeling of prevalent cardiac diseases. Special attention is paid to the application of micro- and nano-engineering techniques for the development of novel iPSC-CM based platforms and their potential to advance current preclinical screening modalities. Published by Elsevier Inc.
Conditional Reliability and the Identification of Communities
2009-11-09
screening is needed to find the factors and interactions that may be relevant. This problem arises in numerous different settings : screening using D...related to the core communities than to each other. and 4. Develop a set of computational methods for conditional reliability. A report describing...resilience address the question: What is the probability that k nodes can communicate? The difference is that for k-terminal reliability, the k communicating
Tatum, C; Wilson, A; Dignan, M; Paskett, E D; Velez, R
1997-01-01
The purpose of the FoCaS (Forsyth County Cancer Screening) Project was to develop and implement strategies that would improve the beliefs, attitudes, and preventive health habits of populations typically considered hard to reach. Conventional health education methods have not produced substantial results; thus, innovative and unusual strategies are needed. The FoCaS project implemented specific methods to reach the targeted population of African American women aged 40 and older that resides in public housing communities. Five outreach strategies were used: 1) educational classes (group setting and one-on-one sessions) on various topics that relate not to breast and cervical cancer but to women's issues in general; 2) media campaigns strategically scheduled throughout the year; 3) the inclusion of religion in educational classes and community outreach; 4) the use of information centers to distribute materials; and 5) a community-wide cancer-awareness event. These strategies reached women in nonthreatening environments that permitted heavy involvement and easy understanding of the importance of breast and cervical cancer screening. The effects of these strategies on promoting screening will be evaluated using data from the follow-up survey conducted during the spring of 1996.
Buhling, Kai J; Lezon, S; Eulenburg, C; Schmalfeldt, B
2017-05-01
The purpose of this study was to systematically analyze the effect of transvaginal ultrasonography in an asymptomatic female population as an annual screening procedure with regard to mortality data. Studies were evaluated descriptively on their strengths and weaknesses considering the methods and results. We evaluated 632 international studies by selecting only randomized controlled trials (RCTs). Three RCTs concerning transvaginal ultrasonography were found, performed in Japan, the USA, and Great Britain. Currently, no clear recommendation for the screening for ovarian cancer in an asymptomatic population can be given based on these three studies. The authors could not show a change in mortality using transvaginal ultrasonography for annual screening. An annual palpation does not offer a beneficial effect. The development of new ultrasound machines with higher image resolution in combination with a well-standardized algorithm for ovarian cancer in upcoming years might provide an improvement regarding mortality. The current studies do not show a benefit in screening an asymptomatic population annually with transvaginal ultrasonography, but the most recent publication showed a trend toward lower mortality in patients who underwent screening after 7-14 years of follow-up. Nevertheless, all three heterogeneous RCTs had weaknesses in their methods and therefore they neither contradict the general recommendation for screening in an asymptomatic population nor do they support it.
Kitahata, Mari M; Drozd, Daniel R; Crane, Heidi M; Van Rompaey, Stephen E; Althoff, Keri N; Gange, Stephen J; Klein, Marina B; Lucas, Gregory M; Abraham, Alison G; Lo Re, Vincent; McReynolds, Justin; Lober, William B; Mendes, Adell; Modur, Sharada P; Jing, Yuezhou; Morton, Elizabeth J; Griffith, Margaret A; Freeman, Aimee M; Moore, Richard D
2015-01-01
The burden of HIV disease has shifted from traditional AIDS-defining illnesses to serious non-AIDS-defining comorbid conditions. Research aimed at improving HIV-related comorbid disease outcomes requires well-defined, verified clinical endpoints. We developed methods to ascertain and verify end-stage renal disease (ESRD) and end-stage liver disease (ESLD) and validated screening algorithms within the largest HIV cohort collaboration in North America (NA-ACCORD). Individuals who screened positive among all participants in twelve cohorts enrolled between January 1996 and December 2009 underwent medical record review to verify incident ESRD or ESLD using standardized protocols. We randomly sampled 6% of contributing cohorts to determine the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of ESLD and ESRD screening algorithms in a validation subcohort. Among 43,433 patients screened for ESRD, 822 screened positive of which 620 met clinical criteria for ESRD. The algorithm had 100% sensitivity, 99% specificity, 82% PPV, and 100% NPV for ESRD. Among 41,463 patients screened for ESLD, 2,024 screened positive of which 645 met diagnostic criteria for ESLD. The algorithm had 100% sensitivity, 95% specificity, 27% PPV, and 100% NPV for ESLD. Our methods proved robust for ascertainment of ESRD and ESLD in persons infected with HIV.
Targeted Provision of Oral Iron: The Evolution of a Practical Screening Option123
Crowley, Caitlin R.; Solomons, Noel W.; Schümann, Klaus
2012-01-01
Universal oral iron supplementation, undertaken according to 1998 WHO guidelines, produced adverse consequences among some children in malaria-endemic areas. Prompted by the Pemba trial, which revealed excessive hospitalizations and deaths, WHO advised that iron supplementation in such regions be accompanied by previous screening for iron deficiency. This agenda, however, poses issues of cost, benefit, acceptability, technical feasibility, and reliability of such screening. The cost of equipment and personnel is balanced against savings from iron supplements spared and treatment for morbidity averted. Costs aside, the most efficacious acceptable screening approach for avoiding hospitalization and deaths must be fielded. Screening before supplementation can be used to assess hematological, iron, and possible inflammatory status to differentiate the source of decreased hemoglobin concentration. Iron deficiency has often been inferred from hematological status markers. The need for extraction of blood, albeit capillary in origin, and high assay costs limit the use of validated methods in screening. Noninvasive methods, i.e., not requiring the extraction of blood, provide the most acceptable and potentially least expensive approach for determining hematological or iron status. Although a noninvasive technique for iron and inflammatory status would be the ideal, it is unattained. Field-friendly, skin-probe hemoglobin devices, derived from instruments for clinical settings, are being developed and tested for eventual rollout in malarial areas. Given a firm grounding for the theoretical requirements needed to advance the screening agenda, evaluation and monitoring of the performance of screening devices can proceed hand in hand. PMID:22797993
[Development and application of CK-MB specific monoclonal antibodies].
Chen, Zimin; Zhou, Guoliang; Xu, Weiling; Zheng, Xiaohong; Tong, Xunzhang; Ke, Qishen; Song, Liuwei; Ge, Shengxiang
2017-01-25
The aim of this study is to develop creatine kinase isoenzyme MB (CK-MB) specific monoclonal antibodies (mAb), and characterize the monoclonal antibody and further development of quantitative detection assay for CK-MB. The BALB/c mice were immunized with purchased CK-MB antigen, then monoclonal antibodies were prepared according to conventional hybridoma technique and screened by indirect and capture ELISA method. To identify the epitopes and evaluate the classification, purchased creatine kinase isoenzyme MB (CK-MM/BB/MB) antigen was used to identify the epitopes, with immunoblotting and synthetic CK-MM and CK-BB in different linear epitope. A double antibody sandwich ELISA was applied to screen the mAb pairs for CK-MB detection, and the quantitative detection assay for CK-MB was developed. We used 74 cases of clinical specimens for comparison of our assay with Roche's CK-MB assay. We successfully developed 22 strains of hybridoms against CK-MB, these mAbs can be divided into linear, partial conformational CK-MB, CK-MM or CK-BB cross monoclonal antibody and CK-MB specific reaction with partial conformational monoclonal antibody, and CK-MB quantitative detection assay was developed by using partial conformational monoclonal antibody. The correlation coefficient factor r of our reagent and Roche's was 0.930 9. This study established a screening method for CK-MB partial conformational specific monoclonal antibody, and these monoclonal antibodies were analyzed and an established quantitative detection assay was developed. The new assay had a high concordance with Roche's.
DEVELOPMENT OF ENVIRONMENTAL INDICES FOR GREEN CHEMICAL PRODUCTION AND USE
Chemical production, use and disposal cause adverse impacts on the environment. Consequently, much research has been conducted to develop methods for estimating the risk of chemicals and to screen them based on environmental impact. Risk assessment may be subdivide...
Guerrero-Romero, Fernando; Rodríguez-Morán, Martha
2010-03-01
To validate a method for screening cases of type 2 diabetes and monitoring at-risk people in a community in northern Mexico. The screening instrument for type 2 diabetes (ITD, for its Spanish acronym) was developed using a multiple logistic regression analysis that made it possible to determine the association between a new diagnosis of diabetes (a dependent variable) and 11 known risk factors. Internal validations were performed (through v-fold cross-validation), together with external validations (through the monitoring of a cohort of healthy individuals). In order to estimate the relative risk (RR) of developing type 2 diabetes, the total ITD score is calculated on the basis of an individual's risk factors and compared against a curve that shows the probability of that individual developing the disease. Of the 525 people in the cohort, 438 (83.4%) were followed for an average of 7 years (4.5 to 10 years), for a total of 2 696 person-years; 62 (14.2%) people developed diabetes during the time they were followed. Individuals scoring 55 points based on their risk factors demonstrated a significantly higher risk of developing diabetes in 7 years (RR = 6.1; IC95%: 1.7 to 11.1); the risk was even higher for those with a score of 75 points (RR = 9.4; IC95%: 2.1 to 11.5). The ITD is easy to use and a valid screening alternative for type 2 diabetes. Its use will allow more individuals to benefit from disease prevention methods and early diagnosis without substantially increasing costs and with minimal use of laboratory resources.
Reimann, S; Grattepanche, F; Baggenstos, C; Rezzonico, E; Berger, B; Arigoni, F; Lacroix, C
2010-06-01
An efficient screening method for selection of Bifidobacterium longum strains resistant to spray drying and storage was developed based on randomly amplified polymorphic DNA (RAPD) for identification of the best survivors in mixed strains bacterial preparations. Three different primers were used to generate RAPD profiles of 22 B. longum strains. All strains were distinguished according to their RAPD profiles except for the strain NCC2705 and its H(2)O(2) resistant derivative variant. The 22 strains were grouped in 3 batches of 7, 7 and 8 strains and subjected to spray drying and storage at 30 and 37 °C under anaerobic conditions. Batch survival rates after spray drying reached 17.1±4.4%. Strains showing the highest prevalence and/or resistance to storage at 37 °C were selected from individual batches for subsequent spray drying and storage testing. After 67 days of storage, NCC572 was identified as the dominant strain in powder. The stability of strain NCC572 was confirmed by performing single spray drying and storage tests. Out of 22 B. longum strains, a robust strain was identified by combining RAPD with a simultaneous screening test for survival under spray drying and storage. The method allowed a fast screening of B. longum strains in mixture for resistance to spray drying and storage compared to traditional screening procedures carried out with individual strains, in the same conditions. This approach could be applied to other stress conditions.
Wass, Sam V
2014-08-01
Convergent research points to the importance of studying the ontogenesis of sustained attention during the early years of life, but little research hitherto has compared and contrasted different techniques available for measuring sustained attention. Here, we compare methods that have been used to assess one parameter of sustained attention, namely infants' peak look duration to novel stimuli. Our focus was to assess whether individual differences in peak look duration are stable across different measurement techniques. In a single cohort of 42 typically developing 11-month-old infants we assessed peak look duration using six different measurement paradigms (four screen-based, two naturalistic). Zero-order correlations suggested that individual differences in peak look duration were stable across all four screen-based paradigms, but no correlations were found between peak look durations observed on the screen-based and the naturalistic paradigms. A factor analysis conducted on the dependent variable of peak look duration identified two factors. All four screen-based tasks loaded onto the first factor, but the two naturalistic tasks did not relate, and mapped onto a different factor. Our results question how individual differences observed on screen-based tasks manifest in more ecologically valid contexts. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.
Wass, Sam V.
2014-01-01
Convergent research points to the importance of studying the ontogenesis of sustained attention during the early years of life, but little research hitherto has compared and contrasted different techniques available for measuring sustained attention. Here, we compare methods that have been used to assess one parameter of sustained attention, namely infants’ peak look duration to novel stimuli. Our focus was to assess whether individual differences in peak look duration are stable across different measurement techniques. In a single cohort of 42 typically developing 11-month-old infants we assessed peak look duration using six different measurement paradigms (four screen-based, two naturalistic). Zero-order correlations suggested that individual differences in peak look duration were stable across all four screen-based paradigms, but no correlations were found between peak look durations observed on the screen-based and the naturalistic paradigms. A factor analysis conducted on the dependent variable of peak look duration identified two factors. All four screen-based tasks loaded onto the first factor, but the two naturalistic tasks did not relate, and mapped onto a different factor. Our results question how individual differences observed on screen-based tasks manifest in more ecologically valid contexts. PMID:24905901
Kayhan, Arda; Arıbal, Erkin; Şahin, Cennet; Taşçı, Ömür Can; Gürdal, Sibel Özkan; Öztürk, Enis; Hatipoğlu, Hayat Halide; Özaydın, Nilüfer; Cabioğlu, Neslihan; Özçınar, Beyza; Özmen, Vahit
2016-01-01
PURPOSE Bahçeşehir Breast Cancer Screening Program is a population based organized screening program in Turkey, where asymptomatic women aged 40–69 years are screened biannually. In this prospective study, we aimed to determine the mammographic findings of screen-detected cancers and discuss the efficacy of breast cancer screening in a developing country. METHODS A total of 6912 women were screened in three rounds. The radiologic findings were grouped as mass, focal asymmetry, calcification, and architectural distortion. Masses were classified according to shape, border, and density. Calcifications were grouped according to morphology and distribution. Cancers were grouped according to the clinical stage. RESULTS Seventy cancers were detected with an incidence of 4.8/1000. Two cancers were detected in other centers and three were not visualized mammographically. Mammographic presentations of the remaining 65 cancers were mass (47.7%, n=31), calcification (30.8%, n=20), focal asymmetry (16.9%, n=11), architectural distortion (3.1%, n=2), and skin thickening (1.5%, n=1). The numbers of stage 0, 1, 2, 3, and 4 cancers were 13 (20.0%), 34 (52.3%), 14 (21.5%), 3 (4.6%), and 1 (1.5%), respectively. The numbers of interval and missed cancers were 5 (7.4%) and 7 (10.3%), respectively. CONCLUSION A high incidence of early breast cancer has been detected. The incidence of missed and interval cancers did not show major differences from western screening trials. We believe that this study will pioneer implementation of efficient population-based mammographic screenings in developing countries. PMID:27705880
Thomas, Brittany; Fitzpatrick, Sandra; Sidani, Souraya; Gucciardi, Enza
2018-06-01
Routine food insecurity screening is recommended in diabetes care to inform more tailored interventions that better support diabetes self-management among food-insecure patients. This pilot study explored the acceptability and feasibility of a food insecurity screening initiative within a diabetes care setting in Toronto. A systematic literature review informed the development of a food insecurity screening initiative to help health-care providers tailor diabetes management plans and better support food-insecure patients with type 2 diabetes. Interviews with 10 patients and a focus group with 15 care providers elicited feedback on the relevance and acceptance of the food insecurity screening questions and a care algorithm. Subsequently, 5 care providers at 4 sites implemented the screening initiative over 2 weeks, screening 33 patients. After implementation, 7 patients and 5 care providers were interviewed to assess the acceptability and feasibility of the screening initiative. Our findings demonstrate that patients are willing to share their experiences of food insecurity, despite the sensitivity of this topic. Screening elicited information about how patients cope with food insecurity and how this affects their ability to self-manage diabetes. Care providers found this information helpful in directing their care and support for patients. Using a standardized, respectful method of assessing food insecurity can better equip health-care providers to support food-insecure patients with diabetes self-management. Further evaluation of this initiative is needed to determine how food insecurity screening can affect patients' self-management and related health outcomes. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
Fathima, Mariam; Naik-Panvelkar, Pradnya; Saini, Bandana; Armour, Carol L
2013-10-01
The purpose of this review was to evaluate the role of community pharmacists in provision of screening with/without subsequent management of undiagnosed chronic obstructive pulmonary disease (COPD) and uncontrolled asthma. An extensive literature search using four databases (ie. Medline, PubMed, International Pharmaceutical Abstracts (IPA) and Scopus) with search terms pharmacy, screening, asthma or COPD was conducted. Searches were limited to the years 2003-2013, those in English and those reporting research with humans. Data retrieval, analysis and result presentation employed a scoping review method. Seventeen articles met the inclusion/exclusion criteria, of which fifteen studies were based on people with asthma and two were based on people with COPD. Only seven asthma studies and one COPD study involved screening followed by subsequent management. More than half of the people screened were found to be poorly controlled and up to 62% of people were identified at high risk for COPD by community pharmacists. The studies varied in the method and type of asthma control assessment/screening, the type of intervention provided and the outcomes measured. The limitations of the reviewed studies included varying definitions of asthma control, different study methodologies, and the lack of long-term follow-up. While many different methods were used for risk assessment and management services by the pharmacists, all the studies demonstrated that community pharmacists were capable of identifying people with poorly controlled asthma and undiagnosed COPD and providing them with suitable interventions. The literature review identified that community pharmacists can play an effective role in screening of people with poorly controlled asthma and undiagnosed COPD along with delivering management interventions. However, there is very little literature available on screening for these chronic respiratory conditions. Future research should focus on development of patient care delivery model incorporating a screening protocol followed by targeted management interventions delivered by the community pharmacist.
Yao, Yong; Zhang, Chunsun
2016-10-01
A novel screen-printed microfluidic paper-based analytical device with all-carbon electrode-enabled electrochemical assay (SP-ACE-EC-μPAD) has been developed. The fabrication of these devices involved wax screen-printing, which was simple, low-cost and energy-efficient. The working, counter and reference electrodes were screen-printed using carbon ink on the patterned paper devices. Different wax screen-printing processes were examined and optimized, which led to an improved method with a shorter heating time (~5 s) and a lower heating temperature (75 °C). Different printing screens were examined, with a 300-mesh polyester screen yielding the highest quality wax screen-prints. The carbon electrodes were screen-printed on the μPADs and then examined using cyclic voltammetry. The analytical performance of the SP-ACE-EC-μPADs for the detection of glucose and uric acid in standard solutions was investigated. The results were reproducible, with a linear relationship [R(2) = 0.9987 (glucose) or 0.9997 (uric acid)] within the concentration range of interest, and with detection limits as low as 0.35 mM (glucose) and 0.08 mM (uric acid). To determine the clinical utility of the μPADs, chronoamperometry was used to analyze glucose and uric acid in real urine samples using the standard addition method. Our devices were able to detect the analytes of interest in complex real-world biological samples, and have the potential for use in a wide variety of applications.
Rahim, Sarni Suhaila; Palade, Vasile; Shuttleworth, James; Jayne, Chrisina
2016-12-01
Digital retinal imaging is a challenging screening method for which effective, robust and cost-effective approaches are still to be developed. Regular screening for diabetic retinopathy and diabetic maculopathy diseases is necessary in order to identify the group at risk of visual impairment. This paper presents a novel automatic detection of diabetic retinopathy and maculopathy in eye fundus images by employing fuzzy image processing techniques. The paper first introduces the existing systems for diabetic retinopathy screening, with an emphasis on the maculopathy detection methods. The proposed medical decision support system consists of four parts, namely: image acquisition, image preprocessing including four retinal structures localisation, feature extraction and the classification of diabetic retinopathy and maculopathy. A combination of fuzzy image processing techniques, the Circular Hough Transform and several feature extraction methods are implemented in the proposed system. The paper also presents a novel technique for the macula region localisation in order to detect the maculopathy. In addition to the proposed detection system, the paper highlights a novel online dataset and it presents the dataset collection, the expert diagnosis process and the advantages of our online database compared to other public eye fundus image databases for diabetic retinopathy purposes.
Local-global classifier fusion for screening chest radiographs
NASA Astrophysics Data System (ADS)
Ding, Meng; Antani, Sameer; Jaeger, Stefan; Xue, Zhiyun; Candemir, Sema; Kohli, Marc; Thoma, George
2017-03-01
Tuberculosis (TB) is a severe comorbidity of HIV and chest x-ray (CXR) analysis is a necessary step in screening for the infective disease. Automatic analysis of digital CXR images for detecting pulmonary abnormalities is critical for population screening, especially in medical resource constrained developing regions. In this article, we describe steps that improve previously reported performance of NLM's CXR screening algorithms and help advance the state of the art in the field. We propose a local-global classifier fusion method where two complementary classification systems are combined. The local classifier focuses on subtle and partial presentation of the disease leveraging information in radiology reports that roughly indicates locations of the abnormalities. In addition, the global classifier models the dominant spatial structure in the gestalt image using GIST descriptor for the semantic differentiation. Finally, the two complementary classifiers are combined using linear fusion, where the weight of each decision is calculated by the confidence probabilities from the two classifiers. We evaluated our method on three datasets in terms of the area under the Receiver Operating Characteristic (ROC) curve, sensitivity, specificity and accuracy. The evaluation demonstrates the superiority of our proposed local-global fusion method over any single classifier.
Lv, Yanni; Sun, Yueming; Fu, Jia; Kong, Liyun; Han, Shengli
2017-02-01
Huangqi (Astragali Radix), a traditional Chinese herb, is widely used in clinical therapy in China. In addition, an anti-allergic effect of constituents in Huangqi has been reported in the scientific literature. In the present study, cell membrane chromatography coupled online with UHPLC-ESI-MS/MS method was developed to screen, analyze and identify the anti-allergic components of Huangqi. The Laboratory of Allergic Disease 2 (LAD2) cell was used to establish cell membrane chromatography, which was combined with UHPLC-ESI-MS/MS. The coupled system was then used to screen anti-allergic components from Huangqi. Effects of active components were verified by histamine release assay. A component retained on the LAD2 cell membrane chromatography was identified as formononetin. Bioactivity of formononetin was investigated by histamine release assay in LAD2 cells, and it was found that formononetin could inhibit histamine release in a dose-dependent manner from 1 to 100 μm. The LAD2 cell membrane chromatography online with UHPLC-ESI-MS/MS method is an effective technique for screening the anti-allergic components of Huangqi. Copyright © 2016 John Wiley & Sons, Ltd.