Immuno-PCR, a new technique for the serodiagnosis of tuberculosis.

Science.gov (United States)

Mehta, Promod K; Dahiya, Bhawna; Sharma, Suman; Singh, Netrapal; Dharra, Renu; Thakur, Zoozeal; Mehta, Neeru; Gupta, Krishna B; Gupta, Mahesh C; Chaudhary, Dhruva

2017-08-01

Rapid and accurate diagnosis of tuberculosis (TB) is essential to control the disease. The conventional microbiological tests have limitations and there is an urgent need to devise a simple, rapid and reliable point-of-care (POC) test. The failure of TB diagnostic tests based on antibody detection due to inconsistent and imprecise results has stimulated renewed interest in the development of rapid antigen detection methods. However, the World Health Organization (WHO) has emphasized to continue research for designing new antibody-based detection tests with improved accuracy. Immuno-polymerase chain reaction (I-PCR) combines the simplicity and versatility of enzyme-linked immunosorbent assay (ELISA) with the exponential amplification capacity and sensitivity of PCR thus leading to several-fold increase in sensitivity in comparison to analogous ELISA. In this review, we have described the serodiagnostic potential of I-PCR assays for an early diagnosis of TB based on the detection of potential mycobacterial antigens and circulating antibodies in body fluids of TB patients. Copyright © 2017 Elsevier B.V. All rights reserved.

Review of two decades of cholera diagnostics--how far have we really come?

Directory of Open Access Journals (Sweden)

Michal H Dick

Full Text Available Cholera, an ancient scourge, continues to inflict high rates of mortality today. The rising incidence of epidemics in areas of poor sanitation and crowding highlight the need for better epidemic prevention and early response. Such interventions require the availability of rapid and accurate diagnostic techniques to trigger timely response and mitigate the scale of the outbreak. The current gold standard of bacterial culture is inadequate for rapid diagnosis, highlighting the overarching neglect of field diagnostic needs. This paper was written to support the World Health Organisation's Global Task Force on Cholera Control mandated Cholera and diarrhoeal disease laboratory Network (CholdiNet in devising a protocol for the validation of Rapid Diagnostic Tests (RDTs for Vibrio cholerae. The status of diagnostic tools for Vibrio cholerae is assessed, describing products that have been commercialised over the last two decades and discussing their peer-reviewed evaluation.Review of post-1990 peer-reviewed and grey literature on rapid diagnostic tests for Vibrio cholerae.Since 1990, twenty four diagnostic tests have been developed for the detection of Vibrio cholerae in human faecal samples. Fourteen of these have also been described in the literature, with rapid chromatographic-immuno assays (CIA featuring strongly. Polymerase chain reaction (PCR assays maintain the ability to detect the lowest amount of bacteria; however CIAs achieve both low detection thresholds and high sensitivity and specificity, making them possible candidates for use in field conditions. Field and laboratory studies were performed in a wide range of settings demonstrating variability in performance, however only a few of these studies were sufficiently stringent, highlighting five RDTs that showed promise in field conditions; COAT, IP cholera dipstick, SMART, IP dipstick and Medicos. In light of non-independent reporting, the authors would like to see these five products

Review of two decades of cholera diagnostics--how far have we really come?

Science.gov (United States)

Dick, Michal H; Guillerm, Martine; Moussy, Francis; Chaignat, Claire-Lise

2012-01-01

Cholera, an ancient scourge, continues to inflict high rates of mortality today. The rising incidence of epidemics in areas of poor sanitation and crowding highlight the need for better epidemic prevention and early response. Such interventions require the availability of rapid and accurate diagnostic techniques to trigger timely response and mitigate the scale of the outbreak. The current gold standard of bacterial culture is inadequate for rapid diagnosis, highlighting the overarching neglect of field diagnostic needs. This paper was written to support the World Health Organisation's Global Task Force on Cholera Control mandated Cholera and diarrhoeal disease laboratory Network (CholdiNet) in devising a protocol for the validation of Rapid Diagnostic Tests (RDTs) for Vibrio cholerae. The status of diagnostic tools for Vibrio cholerae is assessed, describing products that have been commercialised over the last two decades and discussing their peer-reviewed evaluation. Review of post-1990 peer-reviewed and grey literature on rapid diagnostic tests for Vibrio cholerae. Since 1990, twenty four diagnostic tests have been developed for the detection of Vibrio cholerae in human faecal samples. Fourteen of these have also been described in the literature, with rapid chromatographic-immuno assays (CIA) featuring strongly. Polymerase chain reaction (PCR) assays maintain the ability to detect the lowest amount of bacteria; however CIAs achieve both low detection thresholds and high sensitivity and specificity, making them possible candidates for use in field conditions. Field and laboratory studies were performed in a wide range of settings demonstrating variability in performance, however only a few of these studies were sufficiently stringent, highlighting five RDTs that showed promise in field conditions; COAT, IP cholera dipstick, SMART, IP dipstick and Medicos. In light of non-independent reporting, the authors would like to see these five products undergoing

Enzyme-immuno assay for total estrogens and human placental lactogen. Comparison with radio-immuno-assay in normal pregnancy-monitoring

International Nuclear Information System (INIS)

Raichvarg, D.; Tallet, F.; Lajeunie, E.; Bonnaire, Y.; Danglas, P.

1980-01-01

The concentrations of estrogens (E) and human placental lactogen (HLP) are estimated in sera by radio immuno-assay (RIA) and enzyme-immuno-assay (EIA). Statistical data indicate mean intra-assay variation coefficients of 7% and 12% for E and HLP tests, respectively. The correlation coefficient (RIA/EIA) are found higher than 0,9% for both hormonal assays. The dilution curves obtained by RIA and EIA are similar. However, Student'test gives a significant difference for E determination. In fact, total E and E 3 only are measured by EIA and RIA, respectively. In most cases biological interferences are negligible except for HLP in presence of higher protein or haemoglobin levels. RIA and EIA are performed to study serum HLP and E levels throughout normal pregnancies. Results allow to use EIA for HLP and E evaluations in pregnancy-monitoring [fr

Review of Two Decades of Cholera Diagnostics – How Far Have We Really Come?

Science.gov (United States)

Dick, Michal H.; Guillerm, Martine; Moussy, Francis; Chaignat, Claire-Lise

2012-01-01

Background Cholera, an ancient scourge, continues to inflict high rates of mortality today. The rising incidence of epidemics in areas of poor sanitation and crowding highlight the need for better epidemic prevention and early response. Such interventions require the availability of rapid and accurate diagnostic techniques to trigger timely response and mitigate the scale of the outbreak. The current gold standard of bacterial culture is inadequate for rapid diagnosis, highlighting the overarching neglect of field diagnostic needs. This paper was written to support the World Health Organisation's Global Task Force on Cholera Control mandated Cholera and diarrhoeal disease laboratory Network (CholdiNet) in devising a protocol for the validation of Rapid Diagnostic Tests (RDTs) for Vibrio cholerae. The status of diagnostic tools for Vibrio cholerae is assessed, describing products that have been commercialised over the last two decades and discussing their peer-reviewed evaluation. Method Review of post-1990 peer-reviewed and grey literature on rapid diagnostic tests for Vibrio cholerae. Results Since 1990, twenty four diagnostic tests have been developed for the detection of Vibrio cholerae in human faecal samples. Fourteen of these have also been described in the literature, with rapid chromatographic-immuno assays (CIA) featuring strongly. Polymerase chain reaction (PCR) assays maintain the ability to detect the lowest amount of bacteria; however CIAs achieve both low detection thresholds and high sensitivity and specificity, making them possible candidates for use in field conditions. Field and laboratory studies were performed in a wide range of settings demonstrating variability in performance, however only a few of these studies were sufficiently stringent, highlighting five RDTs that showed promise in field conditions; COAT, IP cholera dipstick, SMART, IP dipstick and Medicos. In light of non-independent reporting, the authors would like to see these five

Comparing ImmunoCard with two EIA assays for Clostridium difficile toxins.

Science.gov (United States)

Chan, Edward L; Seales, Diane; Drum, Hong

2009-01-01

To compare three Clostridium difficile EIA kits for the detection of C. difficile toxins from clinical specimens. A total of 287 fresh and stored stool specimens were tested using all three assays. Stools with discrepant results were sent to a reference laboratory for tissue cytotoxin assay. Trinity Medical Center, a community hospital with network hospitals. Patients with diarrhea submitted stools for detection of C. difficile toxins. Of the 287 stool specimens, 116 were positive and 171 negative for C. difficile toxins. The sensitivity, specificity, and positive and negative predictive values of Meridian EIA assay were 99.1, 97.7, 96.6, and 99.4%; ImmunoCard were 100, 98.2, 97.5, and 100%; BioStar OIA assay were 94, 98.8, 98.2, and 96% respectively. ImmunoCardprovides the best sensitivity (100%) for C. difficile toxins A and B detection. The BioStar OIA rapid test missed seven positive stool specimens possibly due to failure to detect toxin B. ImmunoCard has slightly higher predictive values, shorter turnaround time and greater convenience compared to the Meridian EIA Assay. ImmunoCard may be cost effective not only in smaller laboratories, but also in high volume laboratories, when used on a STAT basis or single request.

ImmunoCAP assays: Pros and cons in allergology.

Science.gov (United States)

van Hage, Marianne; Hamsten, Carl; Valenta, Rudolf

2017-10-01

Allergen-specific IgE measurements and the clinical history are the cornerstones of allergy diagnosis. During the past decades, both characterization and standardization of allergen extracts and assay technology have improved. Here we discuss the uses, advantages, misinterpretations, and limitations of ImmunoCAP IgE assays (Thermo Fisher Scientific/Phadia, Uppsala, Sweden) in the field of allergology. They can be performed as singleplex (ImmunoCAP) and, for the last decade, as multiplex (Immuno Solid-phase Allergen Chip [ISAC]). The major benefit of ImmunoCAP is the obtained quantified allergen-specific IgE antibody level and the lack of interference from allergen-specific IgG antibodies. However, ImmunoCAP allergen extracts are limited to the composition of the extract. The introduction of allergen molecules has had a major effect on analytic specificity and allergy diagnosis. They are used in both singleplex ImmunoCAP and multiplex ImmunoCAP ISAC assays. The major advantage of ISAC is the comprehensive IgE pattern obtained with a minute amount of serum. The shortcomings are its semiquantitative measurements, lower linear range, and cost per assay. With respect to assay performance, ImmunoCAP allergen extracts are good screening tools, but allergen molecules dissect the IgE response on a molecular level and put allergy research on the map of precision medicine. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

HIV misdiagnosis in sub-Saharan Africa: performance of diagnostic algorithms at six testing sites

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Kosack, Cara S.; Shanks, Leslie; Beelaert, Greet; Benson, Tumwesigye; Savane, Aboubacar; Ng’ang’a, Anne; Andre, Bita; Zahinda, Jean-Paul BN; Fransen, Katrien; Page, Anne-Laure

2017-01-01

Abstract Introduction: We evaluated the diagnostic accuracy of HIV testing algorithms at six programmes in five sub-Saharan African countries. Methods: In this prospective multisite diagnostic evaluation study (Conakry, Guinea; Kitgum, Uganda; Arua, Uganda; Homa Bay, Kenya; Doula, Cameroun and Baraka, Democratic Republic of Congo), samples from clients (greater than equal to five years of age) testing for HIV were collected and compared to a state-of-the-art algorithm from the AIDS reference laboratory at the Institute of Tropical Medicine, Belgium. The reference algorithm consisted of an enzyme-linked immuno-sorbent assay, a line-immunoassay, a single antigen-enzyme immunoassay and a DNA polymerase chain reaction test. Results: Between August 2011 and January 2015, over 14,000 clients were tested for HIV at 6 HIV counselling and testing sites. Of those, 2786 (median age: 30; 38.1% males) were included in the study. Sensitivity of the testing algorithms ranged from 89.5% in Arua to 100% in Douala and Conakry, while specificity ranged from 98.3% in Doula to 100% in Conakry. Overall, 24 (0.9%) clients, and as many as 8 per site (1.7%), were misdiagnosed, with 16 false-positive and 8 false-negative results. Six false-negative specimens were retested with the on-site algorithm on the same sample and were found to be positive. Conversely, 13 false-positive specimens were retested: 8 remained false-positive with the on-site algorithm. Conclusions: The performance of algorithms at several sites failed to meet expectations and thresholds set by the World Health Organization, with unacceptably high rates of false results. Alongside the careful selection of rapid diagnostic tests and the validation of algorithms, strictly observing correct procedures can reduce the risk of false results. In the meantime, to identify false-positive diagnoses at initial testing, patients should be retested upon initiating antiretroviral therapy. PMID:28691437

42 CFR 410.32 - Diagnostic x-ray tests, diagnostic laboratory tests, and other diagnostic tests: Conditions.

Science.gov (United States)

2010-10-01

... Procedural Terminology published by the American Medical Association. (3) Levels of supervision. Except where... & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE PROGRAM SUPPLEMENTARY MEDICAL INSURANCE (SMI) BENEFITS Medical and Other Health Services § 410.32 Diagnostic x-ray tests, diagnostic laboratory...

An assessment of the usefulness of a rapid immuno-chromatographic test, "Determine™ malaria pf" in evaluation of intervention measures in forest villages of central India

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Shukla Manmohan

2001-08-01

Full Text Available Abstract Background Plasmodium falciparum malaria, is a major health problem in forested tribal belt of central India. Rapid and accurate methods are needed for the diagnosis of P. falciparum. We performed a blinded evaluation of the recently introduced Determine™ malaria pf test (Abbott, Laboratories, Japan compared with microscopy and splenomegaly in children in epidemic prone areas of district Mandla to assess the impact of intervention measures. Methods Children aged 2–10 yrs with and without fever were examined for spleen enlargement by medical specialist by establishing a mobile field clinic. From these children thick blood smears were prepared from finger prick and read by a technician. Simultaneously, rapid tests were performed by a field lab attendant. The figures for specificity, sensitivity and predictive values were calculated using microscopy as gold standard. Results In all 349 children were examined. The sensitivity and specificity for Determine rapid diagnostic test were 91 and 80% respectively. The positive predictive values (PPV, negative predictive values (NPV and accuracy of the test were respectively 79, 91 and 85%. On the contrary, the sensitivity and specificity of spleen in detecting malaria infection were 57 and 74 % respectively with PPV of 73%, NPV 59 % and an accuracy of 65%. Conclusions Determine™ malaria rapid diagnostic test is easier and quicker to perform and has other advantages over microscopy in not requiring prior training of personnel or quality control. Thus, highlighting the usefulness of a rapid antigen test in assessing prevailing malaria situation in remote areas.

Antibodies and antimatter: the resurgence of immuno-PET.

Science.gov (United States)

Wu, Anna M

2009-01-01

The completion of the human genome, coupled with parallel major research efforts in proteomics and systems biology, has led to a flood of information on the roles of individual genes and proteins in normal physiologic processes and their disruptions in disease. In practical terms, this information has opened the door to increasingly targeted therapies as specific molecular markers are identified and validated. The ongoing transition from empiric to molecular medicine has engendered a need for corresponding molecular diagnostics, including noninvasive molecular imaging. Convergence of knowledge regarding key biomarkers that define normal biologic processes and disease with protein and imaging technology makes this an opportune time to revisit the combination of antibodies and PET, or immuno-PET.

Test plan for demonstrating plutonium extraction from 10-L solutions using EIChrom extraction chromatographic resins

International Nuclear Information System (INIS)

Barney, G.S.

1994-01-01

Corrosive plutonium solutions stored in 10-L containers at the Plutonium Finishing Plant must be treated to convert the plutonium to a safe, solid form for storage and to remove the americium so that radiation exposure can be reduced. Extraction chromatographic resins will be tested for separating plutonium from these solutions in the laboratory. Separation parameters will be developed during the testing for large scale processing of the 10-L solutions and solutions of similar composition. Use of chromatographic resins will allow plutonium separation with minimum of chemical addition to the feed and without the need for plutonium valence adjustment. The separated plutonium will be calcined to plutonium oxide by direct solution calcination

Beyond Diagnostic Accuracy: The Clinical Utility of Diagnostic Tests

NARCIS (Netherlands)

Bossuyt, Patrick M. M.; Reitsma, Johannes B.; Linnet, Kristian; Moons, Karel G. M.

2012-01-01

Like any other medical technology or intervention, diagnostic tests should be thoroughly evaluated before their introduction into daily practice. Increasingly, decision makers, physicians, and other users of diagnostic tests request more than simple measures of a test's analytical or technical

New method for evaluating irreversible adsorption and stationary phase bleed in gas chromatographic capillary columns.

Science.gov (United States)

Wright, Bob W; Wright, Cherylyn W

2012-10-26

A novel method is described for the evaluation of irreversible adsorption and column bleed in gas chromatographic (GC) columns using a tandem GC approach. This work specifically determined the degree of irreversible adsorption behavior of specific sulfur and phosphorous containing test probe compounds at levels ranging from approximately 50 picograms (pg) to 1 nanogram (ng) on selected gas chromatographic columns. This method does not replace existing evaluation methods that characterize reversible adsorption but provides an additional tool. The test compounds were selected due to their ease of adsorption and their importance in the specific trace analytical detection methodology being developed. Replicate chromatographic columns with 5% phenylmethylpolysiloxane (PMS), polyethylene glycol (wax), trifluoropropylpolysiloxane (TFP), or 78% cyanopropylpolysiloxane stationary phases from a variety of vendors were evaluated. As expected, the results demonstrate that the different chromatographic phases exhibit differing degrees of irreversible adsorption behavior. The results also indicate that all manufacturers do not produce equally inert columns nor are columns from a given manufacturer identical. The wax-coated columns for the test probes used were more inert as a group than 5% PMS coated columns, and they were more reproducibly manufactured. Both TFP and 78% cyanopropylpolysiloxane columns displayed superior inertness to the test compounds compared to either 5% PMS- or wax-coated columns. Irreversible adsorption behavior was characterized for a limited range of stationary phase film thicknesses. In addition, the method was shown effective for characterizing column bleed and methods to remove bleed components. This method is useful in screening columns for demanding applications and to obtain diagnostic information related to improved preparation methods. Copyright © 2012 Elsevier B.V. All rights reserved.

21 CFR 864.9285 - Automated cell-washing centrifuge for immuno-hematology.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Automated cell-washing centrifuge for immuno... Establishments That Manufacture Blood and Blood Products § 864.9285 Automated cell-washing centrifuge for immuno-hematology. (a) Identification. An automated cell-washing centrifuge for immuno-hematology is a device used...

A novel immuno-gold labeling protocol for nanobody-based detection of HER2 in breast cancer cells using immuno-electron microscopy.

Science.gov (United States)

Kijanka, M; van Donselaar, E G; Müller, W H; Dorresteijn, B; Popov-Čeleketić, D; El Khattabi, M; Verrips, C T; van Bergen En Henegouwen, P M P; Post, J A

2017-07-01

Immuno-electron microscopy is commonly performed with the use of antibodies. In the last decade the antibody fragment indicated as nanobody (VHH or single domain antibody) has found its way to different applications previously done with conventional antibodies. Nanobodies can be selected to bind with high affinity and specificity to different antigens. They are small (molecular weight ca. 15kDa) and are usually easy to produce in microorganisms. Here we have evaluated the feasibility of a nanobody binding to HER2 for application in immuno-electron microscopy. To obtain highest labeling efficiency combined with optimal specificity, different labeling conditions were analysed, which included nanobody concentration, fixation and blocking conditions. The obtained optimal protocol was applied for post-embedment labeling of Tokuyasu cryosections and for pre-embedment labeling of HER2 for fluorescence microscopy and both transmission and scanning electron microscopy. We show that formaldehyde fixation after incubation with the anti-HER2 nanobody, improves labeling intensity. Among all tested blocking agents the best results were obtained with a mixture of cold water fish gelatine and acetylated bovine serum albumin, which prevented a-specific interactions causing background labeling while preserving specific interactions at the same time. In conclusion, we have developed a nanobody-based protocol for immuno-gold labeling of HER2 for Tokuyasu cryosections in TEM as well as for pre-embedment gold labeling of cells for both TEM and SEM. Copyright © 2017. Published by Elsevier Inc.

Comparing diagnostic tests on benefit-risk.

Science.gov (United States)

Pennello, Gene; Pantoja-Galicia, Norberto; Evans, Scott

2016-01-01

Comparing diagnostic tests on accuracy alone can be inconclusive. For example, a test may have better sensitivity than another test yet worse specificity. Comparing tests on benefit risk may be more conclusive because clinical consequences of diagnostic error are considered. For benefit-risk evaluation, we propose diagnostic yield, the expected distribution of subjects with true positive, false positive, true negative, and false negative test results in a hypothetical population. We construct a table of diagnostic yield that includes the number of false positive subjects experiencing adverse consequences from unnecessary work-up. We then develop a decision theory for evaluating tests. The theory provides additional interpretation to quantities in the diagnostic yield table. It also indicates that the expected utility of a test relative to a perfect test is a weighted accuracy measure, the average of sensitivity and specificity weighted for prevalence and relative importance of false positive and false negative testing errors, also interpretable as the cost-benefit ratio of treating non-diseased and diseased subjects. We propose plots of diagnostic yield, weighted accuracy, and relative net benefit of tests as functions of prevalence or cost-benefit ratio. Concepts are illustrated with hypothetical screening tests for colorectal cancer with test positive subjects being referred to colonoscopy.

How to appraise a diagnostic test

Directory of Open Access Journals (Sweden)

Ramanitharan Manikandan

2011-01-01

Full Text Available Urologists frequently encounter problems in making a clinical diagnosis whose resolution requires the use of diagnostic tests. With an ever increasing choice of investigations being available, the urologist often has to decide which diagnostic test(s will best resolve the patient′s diagnostic problem. In this article, we aim to help the urologist understand how to critically appraise studies on diagnostic tests and make a rational choice. This article presents the guiding principles in scientifically assessing studies on diagnostic tests by proposing a clinical scenario. The authors describe a standardized protocol to assess the validity of the test and its relevance to the clinical problem that can help the urologist in decision making. The three important issues to be considered when evaluating the validity of the study are to identify how the study population was chosen, how the test was performed and whether there is a comparison to the gold standard test so as to confirm or refute the diagnosis. Then, the urologist would need to know the probability of the test in providing the correct diagnosis in an individual patient in order to decide about its utility in solving the diagnostic dilemma. By performing the steps described in this article, the urologist would be able to critically appraise diagnostic studies and draw meaningful conclusions about the investigations in terms of validity, results and its applicability to the patient′s problem. This would provide a scientific basis for using diagnostic tests for improving patient care.

Modeling Aquatic Toxicity through Chromatographic Systems.

Science.gov (United States)

Fernández-Pumarega, Alejandro; Amézqueta, Susana; Farré, Sandra; Muñoz-Pascual, Laura; Abraham, Michael H; Fuguet, Elisabet; Rosés, Martí

2017-08-01

Environmental risk assessment requires information about the toxicity of the growing number of chemical products coming from different origins that can contaminate water and become toxicants to aquatic species or other living beings via the trophic chain. Direct toxicity measurements using sensitive aquatic species can be carried out but they may become expensive and ethically questionable. Literature refers to the use of chromatographic measurements that correlate to the toxic effect of a compound over a specific aquatic species as an alternative to get toxicity information. In this work, we have studied the similarity in the response of the toxicity to different species and we have selected eight representative aquatic species (including tadpoles, fish, water fleas, protozoan, and bacteria) with known nonspecific toxicity to chemical substances. Next, we have selected four chromatographic systems offering good perspectives for surrogation of the eight selected aquatic systems, and thus prediction of toxicity from the chromatographic measurement. Then toxicity has been correlated to the chromatographic retention factor. Satisfactory correlation results have been obtained to emulate toxicity in five of the selected aquatic species through some of the chromatographic systems. Other aquatic species with similar characteristics to these five representative ones could also be emulated by using the same chromatographic systems. The final aim of this study is to model chemical products toxicity to aquatic species by means of chromatographic systems to reduce in vivo testing.

Severe childhood asthma and allergy to furry animals: refined assessment using molecular-based allergy diagnostics.

Science.gov (United States)

Konradsen, Jon R; Nordlund, Björn; Onell, Annica; Borres, Magnus P; Grönlund, Hans; Hedlin, Gunilla

2014-03-01

Allergy to cats and dogs and polysensitization towards these animals are associated with severe childhood asthma. Molecular-based allergy diagnostics offers new opportunities for improved characterization and has been suggested to be particularly useful in patients with polysensitization and/or severe asthma. The aim was to use extract- and molecular-based allergy diagnostics to compare patterns of IgE sensitization towards aeroallergens in children with problematic severe and controlled asthma. Children with a positive ImmunoCAP towards any furry animal (cat, dog or horse) were recruited from a Nationwide Swedish study on severe childhood asthma. Severe (n = 37, age 13 years) and controlled (n = 28, age 14 years) asthmatics underwent assessment of allergic sensitization by ImmunoCap (kUA /l) and immunosolid-phase allergen chip (ISAC). In addition, Asthma Control Test, spirometry and a methacholine challenge were performed. Children with severe asthma had lower asthma control (p Molecular-based allergy diagnostics revealed a more complex molecular spreading of allergen components in children with the most severe disease. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Gas-Chromatographic Determination Of Water In Freon PCA

Science.gov (United States)

Melton, Donald M.

1994-01-01

Gas-chromatographic apparatus measures small concentrations of water in specimens of Freon PCA. Testing by use of apparatus faster and provides greater protection against accidental contamination of specimens by water in testing environment. Automated for unattended operation. Also used to measure water contents of materials, other than Freon PCA. Innovation extended to development of purgeable sampling accessory for gas chromatographs.

Serological Tests for Acquired Syphilis in Immuno-competent Patients

Directory of Open Access Journals (Sweden)

Golušin Zoran

2016-06-01

Full Text Available Serological tests represent a valuable tool for the diagnosis and monitoring the syphilis treatment. Non-treponemal antibodies are nonspecific to detect the infection, but antibody titers are used to monitor the effects of syphilis treatment. A definitive diagnosis of syphilis is made using treponemal tests, because they detect specific antibodies to the treponemal strains or treponemal fragments, which cause syphilis. These tests may remain reactive for years, sometimes for life, regardless of the therapy outcome. Even after successful treatment, approximately 85% of patients remain positive for treponemal antibodies for the rest of their lives. However, treponemal tests cannot differentiate past infections from a current infection. Therefore, we use a combination of specific and non-specific tests, the two most frequently used diagnostic algorithms. The traditional algorithm begins with a non-treponemal assay, and if it is positive, the treponemal test is done. A positive treponemal test indicates syphilis. The reverse serology algorithm detects early, primary, and treated syphilis that may be missed with traditional screening. However, non-treponemal test is necessary to detect patients with active syphilis.

Combined time-lapse cinematography and immuno-electron microscopy.

Science.gov (United States)

Balfour, B M; Goscicka, T; MacKenzie, J L; Gautam, A; Tate, M; Clark, J

1990-04-01

A method was developed to record interactions between mobile non-adherent immunocytes by time-lapse cinematography and then to study the same cells by immuno-electron microscopy, using monoclonal antibodies against surface components. For this purpose a modified stage was designed to fit an inverted microscope. The attachment included a device to cool the culture chamber with N2 gas, a micro-injector for monoclonal antibody and immuno-gold treatment, and two pairs of washing needles to change the medium without disturbance. The technique was first employed to study the formation of aggregates around the antigen-presenting cells in cultures containing cells from hyper-immunized animals. Recently peripheral blood cells from normal subjects and patients with immune deficiency syndromes were stimulated with pokeweed mitogen, cluster formation was recorded, and the cells were processed for immuno-electron microscopy.

1968 Prototype Diagnostic Test.

Science.gov (United States)

Veterans Administration Hospital, Bedford, MA.

This true-false diagnostic test was used for pretesting of employees at a Veterans Administration Hospital. The test is comprised of 20 items. An alternate test--Classification Questionnaire--was used for testing after remedial training. (For related document, see TM 002 334.) (DB)

The diagnostic accuracy of serological tests for Lyme borreliosis in Europe: a systematic review and meta-analysis.

Science.gov (United States)

Leeflang, M M G; Ang, C W; Berkhout, J; Bijlmer, H A; Van Bortel, W; Brandenburg, A H; Van Burgel, N D; Van Dam, A P; Dessau, R B; Fingerle, V; Hovius, J W R; Jaulhac, B; Meijer, B; Van Pelt, W; Schellekens, J F P; Spijker, R; Stelma, F F; Stanek, G; Verduyn-Lunel, F; Zeller, H; Sprong, H

2016-03-25

Interpretation of serological assays in Lyme borreliosis requires an understanding of the clinical indications and the limitations of the currently available tests. We therefore systematically reviewed the accuracy of serological tests for the diagnosis of Lyme borreliosis in Europe. We searched EMBASE en MEDLINE and contacted experts. Studies evaluating the diagnostic accuracy of serological assays for Lyme borreliosis in Europe were eligible. Study selection and data-extraction were done by two authors independently. We assessed study quality using the QUADAS-2 checklist. We used a hierarchical summary ROC meta-regression method for the meta-analyses. Potential sources of heterogeneity were test-type, commercial or in-house, Ig-type, antigen type and study quality. These were added as covariates to the model, to assess their effect on test accuracy. Seventy-eight studies evaluating an Enzyme-Linked ImmunoSorbent assay (ELISA) or an immunoblot assay against a reference standard of clinical criteria were included. None of the studies had low risk of bias for all QUADAS-2 domains. Sensitivity was highly heterogeneous, with summary estimates: erythema migrans 50% (95% CI 40% to 61%); neuroborreliosis 77% (95% CI 67% to 85%); acrodermatitis chronica atrophicans 97% (95% CI 94% to 99%); unspecified Lyme borreliosis 73% (95% CI 53% to 87%). Specificity was around 95% in studies with healthy controls, but around 80% in cross-sectional studies. Two-tiered algorithms or antibody indices did not outperform single test approaches. The observed heterogeneity and risk of bias complicate the extrapolation of our results to clinical practice. The usefulness of the serological tests for Lyme disease depends on the pre-test probability and subsequent predictive values in the setting where the tests are being used. Future diagnostic accuracy studies should be prospectively planned cross-sectional studies, done in settings where the test will be used in practice.

Recombinant antigen-based immuno-slot blot method for serodiagnosis of syphilis

Directory of Open Access Journals (Sweden)

N.S. Sato

2004-07-01

Full Text Available Three recombinant antigens of Treponema pallidum Nichols strain were fused with GST, cloned and expressed in Escherichia coli, resulting in high levels of GST-rTp47 and GST-rTp17 expression, and supplementation with arginine tRNA for the AGR codon was needed to obtain GST-rTp15 overexpression. Purified fusion protein yields were 1.9, 1.7 and 5.3 mg/l of cell culture for GST-rTp47, GST-rTp17 and GST-rTp15, respectively. The identities of the antigens obtained were confirmed by automated DNA sequencing using ABI Prism 310 and peptide mapping by Finningan LC/MS. These recombinant antigens were evaluated by immuno-slot blot techniques applied to 137 serum samples from patients with a clinical and laboratory diagnosis of syphilis (61 samples, from healthy blood donors (50 samples, individuals with sexually transmitted disease other than syphilis (3 samples, and from individuals with other spirochetal diseases such as Lyme disease (20 samples and leptospirosis (3 samples. The assay had sensitivity of 95.1% (95% CI, 86.1 to 98.7% and a specificity of 94.7% (95% CI, 87.0 to 98.7%; a stronger reactivity was observed with fraction rTp17. The immunoreactivity results showed that fusion recombinant antigens based-immuno-slot blot techniques are suitable for use in diagnostic assays for syphilis.

Myasthenia Gravis: Tests and Diagnostic Methods

Science.gov (United States)

... Focus on MG Newsletter MG Quarterly Test & Diagnostic methods In addition to a complete medical and neurological ... How can I help? About MGFA Test & Diagnostic methods Treatment for MG FAQ's Upcoming Events 2018 MG ...

Diagnosis of asthma: diagnostic testing.

Science.gov (United States)

Brigham, Emily P; West, Natalie E

2015-09-01

Asthma is a heterogeneous disease, encompassing both atopic and non-atopic phenotypes. Diagnosis of asthma is based on the combined presence of typical symptoms and objective tests of lung function. Objective diagnostic testing consists of 2 components: (1) demonstration of airway obstruction, and (2) documentation of variability in degree of obstruction. A review of current guidelines and literature was performed regarding diagnostic testing for asthma. Spirometry with bronchodilator reversibility testing remains the mainstay of asthma diagnostic testing for children and adults. Repetition of the test over several time points may be necessary to confirm airway obstruction and variability thereof. Repeated peak flow measurement is relatively simple to implement in a clinical and home setting. Bronchial challenge testing is reserved for patients in whom the aforementioned testing has been unrevealing but clinical suspicion remains, though is associated with low specificity. Demonstration of eosinophilic inflammation, via fractional exhaled nitric oxide measurement, or atopy, may be supportive of atopic asthma, though diagnostic utility is limited particularly in nonatopic asthma. All efforts should be made to confirm the diagnosis of asthma in those who are being presumptively treated but have not had objective measurements of variability in the degree of obstruction. Multiple testing modalities are available for objective confirmation of airway obstruction and variability thereof, consistent with a diagnosis of asthma in the appropriate clinical context. Providers should be aware that both these characteristics may be present in other disease states, and may not be specific to a diagnosis of asthma. © 2015 ARS-AAOA, LLC.

Using Delphi to realize the function of the γ-immuno counter

International Nuclear Information System (INIS)

Qi Na; Chu Yan; He Wenhua

2005-01-01

This paper introduces the concept of Radioimmunoassay and the background of the γ-immuno counter, summarizes the feature of the Delphi and discusses the superiority of using language of Delphi to realize the function of γ-immuno counter. (authors)

A simple subcritical chromatographic test for an extended ODS high performance liquid chromatography column classification.

Science.gov (United States)

Lesellier, Eric; Tchapla, Alain

2005-12-23

This paper describes a new test designed in subcritical fluid chromatography (SFC) to compare the commercial C18 stationary phase properties. This test provides, from a single analysis of carotenoid pigments, the absolute hydrophobicity, the silanol activity and the steric separation factor of the ODS stationary phases. Both the choice of the analytical conditions and the validation of the information obtained from the chromatographic measurements are detailed. Correlations of the carotenoid test results with results obtained from other tests (Tanaka, Engelhard, Sander and Wise) performed both in SFC and HPLC are discussed. Two separation factors, calculated from the retention of carotenoid pigments used as probe, allowed to draw a first classification diagram. Columns, which present identical chromatographic behaviors are located in the same area on this diagram. This location can be related to the stationary phase properties: endcapping treatments, bonding density, linkage functionality, specific area or silica pore diameter. From the first classification, eight groups of columns are distinguished. One group of polymer coated silica, three groups of polymeric octadecyl phases, depending on the pore size and the endcapping treatment, and four groups of monomeric stationary phases. An additional classification of the four monomeric groups allows the comparison of these stationary phases inside each group by using the total hydrophobicity. One hundred and twenty-nine columns were analysed by this simple and rapid test, which allows a comparison of columns with the aim of helping along their choice in HPLC.

An ImmunoSignature test distinguishes Trypanosoma cruzi, hepatitis B, hepatitis C and West Nile virus seropositivity among asymptomatic blood donors.

Directory of Open Access Journals (Sweden)

Michael Rowe

2017-09-01

Full Text Available The complexity of the eukaryotic parasite Trypanosoma (T. cruzi manifests in its highly dynamic genome, multi-host life cycle, progressive morphologies and immune-evasion mechanisms. Accurate determination of infection or Chagas' disease activity and prognosis continues to challenge researchers. We hypothesized that a diagnostic platform with higher ligand complexity than previously employed may hold value.We applied the ImmunoSignature Technology (IST for the detection of T. cruzi-specific antibodies among healthy blood donors. IST is based on capturing the information in an individual's antibody repertoire by exposing their peripheral blood to a library of >100,000 position-addressable, chemically-diverse peptides.Initially, samples from two Chagas cohorts declared positive or negative by bank testing were studied. With the first cohort, library-peptides displaying differential binding signals between T. cruzi sero-states were used to train an algorithm. A classifier was fixed and tested against the training-independent second cohort to determine assay performance. Next, samples from a mixed cohort of donors declared positive for Chagas, hepatitis B, hepatitis C or West Nile virus were assayed on the same library. Signals were used to train a single algorithm that distinguished all four disease states. As a binary test, the accuracy of predicting T. cruzi seropositivity by IST was similar, perhaps modestly reduced, relative to conventional ELISAs. However, the results indicate that information beyond determination of seropositivity may have been captured. These include the identification of cohort subclasses, the simultaneous detection and discerning of other diseases, and the discovery of putative new antigens.The central outcome of this study established IST as a reliable approach for specific determination of T. cruzi seropositivity versus disease-free individuals or those with other diseases. Its potential contribution for monitoring and

Methodology of diagnostic tests in hepatology

DEFF Research Database (Denmark)

Christensen, Erik

2009-01-01

The performance of diagnostic tests can be assessed by a number of methods. These include sensitivity, specificity,positive and negative predictive values, likelihood ratios and receiver operating characteristic (ROC) curves. This paper describes the methods and explains which information...... they provide. Sensitivity and specificity provides measures of the diagnostic accuracy of a test in diagnosing the condition. The positive and negative predictive values estimate the probability of the condition from the test-outcome and the condition's prevalence. The likelihood ratios bring together......' and plotting sensitivity as a function of 1-specificity. The ROC-curve can be used to define optimal cut-off values for a test, to assess the diagnostic accuracy of the test, and to compare the usefulness of different tests in the same patients. Under certain conditions it may be possible to utilize a test...

A novel design for randomized immuno-oncology clinical trials with potentially delayed treatment effects

Directory of Open Access Journals (Sweden)

Pei He

2015-10-01

Full Text Available The semi-parametric proportional hazards model is widely adopted in randomized clinical trials with time-to-event outcomes, and the log-rank test is frequently used to detect a potential treatment effect. Immuno-oncology therapies pose unique challenges to the design of a trial as the treatment effect may be delayed, which violates the proportional hazards assumption, and the log-rank test has been shown to markedly lose power under the non-proportional hazards setting. A novel design and analysis approach for immuno-oncology trials is proposed through a piecewise treatment effect function, which is capable of detecting a potentially delayed treatment effect. The number of events required for the trial will be determined to ensure sufficient power for both the overall log-rank test without a delayed effect and the test beyond the delayed period when such a delay exists. The existence of a treatment delay is determined by a likelihood ratio test with resampling. Numerical results show that the proposed design adequately controls the Type I error rate, has a minimal loss in power under the proportional hazards setting and is markedly more powerful than the log-rank test with a delayed treatment effect.

Tus-Ter-lock immuno-PCR assays for the sensitive detection of tropomyosin-specific IgE antibodies.

Science.gov (United States)

Johnston, Elecia B; Kamath, Sandip D; Lopata, Andreas L; Schaeffer, Patrick M

2014-02-01

The increasing prevalence of food allergies requires development of specific and sensitive tests capable of identifying the allergen responsible for the disease. The development of serologic tests that can detect specific IgE antibodies to allergenic proteins would, therefore, be highly received. Here we present two new quantitative immuno-PCR assays for the sensitive detection of antibodies specific to the shrimp allergen tropomyosin. Both assays are based on the self-assembling Tus-Ter-lock protein-DNA conjugation system. Significantly elevated levels of tropomyosin-specific IgE were detected in sera from patients allergic to shrimp. This is the first time an allergenic protein has been fused with Tus to enable specific IgE antibody detection in human sera by quantitative immuno-PCR.

Draw your assay: Fabrication of low-cost paper-based diagnostic and multi-well test zones by drawing on a paper.

Science.gov (United States)

Oyola-Reynoso, Stephanie; Heim, Andrew P; Halbertsma-Black, Julian; Zhao, C; Tevis, Ian D; Çınar, Simge; Cademartiri, Rebecca; Liu, Xinyu; Bloch, Jean-Francis; Thuo, Martin M

2015-11-01

Interest in low-cost diagnostic devices has recently gained attention, in part due to the rising cost of healthcare and the need to serve populations in resource-limited settings. A major challenge in the development of such devices is the need for hydrophobic barriers to contain polar bio-fluid analytes. Key approaches in lowering the cost in diagnostics have centered on (i) development of low-cost fabrication techniques/processes, (ii) use of affordable materials, or, (iii) minimizing the need for high-tech tools. This communication describes a simple, low-cost, adaptable, and portable method for patterning paper and subsequent use of the patterned paper in diagnostic tests. Our approach generates hydrophobic regions using a ball-point pen filled with a hydrophobizing molecule suspended in a solvent carrier. An empty ball-point pen was filled with a solution of trichloro perfluoroalkyl silane in hexanes (or hexadecane), and the pen used to draw lines on Whatman® chromatography 1 paper. The drawn regions defined the test zones since the trichloro silane reacts with the paper to give a hydrophobic barrier. The formation of the hydrophobic barriers is reaction kinetic and diffusion-limited, ensuring well defined narrow barriers. We performed colorimetric glucose assays and enzyme-linked immuno-sorbent assay (ELISA) using the created test zones. To demonstrate the versatility of this approach, we fabricated multiple devices on a single piece of paper and demonstrated the reproducibility of assays on these devices. The overall cost of devices fabricated by drawing are relatively lower (

Effects of an immuno-enhanced diet containing antioxidants in esophageal cancer surgery following neoadjuvant therapy.

Science.gov (United States)

Aiko, S; Kumano, I; Yamanaka, N; Tsujimoto, H; Takahata, R; Maehara, T

2012-02-01

Neoadjuvant therapy-induced immunological deterioration may be a key factor in postoperative morbidity in patients with esophageal cancer. This study aimed to determine the effects of perioperative feeding with an immuno-enhanced diet on immune competence in patients treated with neoadjuvant therapy followed by surgery. Because an immuno-enhanced diet that contained several antioxidants was used, perioperative oxidative stress and the effects of the immuno-enhanced diet on this stress were also investigated. Of 39 patients with esophageal cancer who underwent similar surgical procedures, 26 patients who received chemotherapy or chemoradiation therapy before surgery were randomly divided into two groups: group 1 (n= 14) was given an immuno-enhanced diet for 5 days before surgery, and group 2 (n= 12) received no enteral feeding products before surgery. Group 3 (n= 13) consisted of patients that did not receive neoadjuvant therapy and received no enteral feeding products before surgery. Several markers for coagulation and fibrinolysis were determined and immunological assessments were performed for each patient. To measure reactive oxygen metabolites and the total antioxidant capacity, diacron-reactive oxygen metabolites (d-ROMs) and OXY-adsorbent tests were performed using a free radical elective evaluator. Significant depression in lymphocyte numbers was observed in groups 1 and 2 before and early after surgery as compared to group 3. Numbers of B cells, CD4/CD8 ratio, and phytohemagglutinin-induced lymphocyte transformation tests were also significantly decreased in groups 1 and 2 on postoperative day 1. Fibrin and fibrinogen degradation products were significantly elevated in group 2 compared to group 1. d-ROMs and OXY-adsorbent test values were elevated before surgery and were decreased transiently early after surgery. Compared to groups 2 and 3, d-ROMs values were significantly lower in group 1 patients throughout the postoperative period, while OXY

Chemometric strategy for automatic chromatographic peak detection and background drift correction in chromatographic data.

Science.gov (United States)

Yu, Yong-Jie; Xia, Qiao-Ling; Wang, Sheng; Wang, Bing; Xie, Fu-Wei; Zhang, Xiao-Bing; Ma, Yun-Ming; Wu, Hai-Long

2014-09-12

Peak detection and background drift correction (BDC) are the key stages in using chemometric methods to analyze chromatographic fingerprints of complex samples. This study developed a novel chemometric strategy for simultaneous automatic chromatographic peak detection and BDC. A robust statistical method was used for intelligent estimation of instrumental noise level coupled with first-order derivative of chromatographic signal to automatically extract chromatographic peaks in the data. A local curve-fitting strategy was then employed for BDC. Simulated and real liquid chromatographic data were designed with various kinds of background drift and degree of overlapped chromatographic peaks to verify the performance of the proposed strategy. The underlying chromatographic peaks can be automatically detected and reasonably integrated by this strategy. Meanwhile, chromatograms with BDC can be precisely obtained. The proposed method was used to analyze a complex gas chromatography dataset that monitored quality changes in plant extracts during storage procedure. Copyright © 2014 Elsevier B.V. All rights reserved.

Dual liquid and gas chromatograph system

Science.gov (United States)

Gay, D.D.

A chromatographic system is described that utilizes one detection system for gas chromatographic and micro-liquid chromatographic determinations. The detection system is a direct-current, atmospheric-pressure, helium plasma emission spectrometer. The detector utilizes a nontransparent plasma source unit which contains the plasma region and two side-arms which receive effluents from the micro-liquid chromatograph and the gas chromatograph. The dual nature of this chromatographic system offers: (1) extreme flexibility in the samples to be examined; (2) extreme low sensitivity; (3) element selectivity; (4) long-term stability; (5) direct correlation of data from the liquid and gas samples; (6) simpler operation than with individual liquid and gas chromatographs, each with different detection systems; and (7) cheaper than a commercial liquid chromatograph and a gas chromatograph.

Thermal soil desorption for total petroleum hydrocarbon testing on gas chromatographs

International Nuclear Information System (INIS)

Mott, J.

1995-01-01

Testing for total petroleum hydrocarbons (TPH) is one of the most common analytical tests today. A recent development in chromatography incorporates Thermal Soil Desorption technology to enable analyses of unprepared soil samples for volatiles such as BTEX components and semi-volatiles such as diesel, PCBs, PAHs and pesticides in the same chromatogram, while in the field. A gas chromatograph is the preferred method for determining TPH because the column in a GC separates the individual hydrocarbons compounds such as benzene and toluene from each other and measures each individually. A GC analysis will determine not only the total amount of hydrocarbon, but also whether it is gasoline, diesel or another compound. TPH analysis with a GC is typically conducted with a Flame Ionization Detector (FID). Extensive field and laboratory testing has shown that incorporation of a Thermal Soil Desorber offers many benefits over traditional analytical testing methods such as Headspace, Solvent Extraction, and Purge and Trap. This paper presents the process of implementing Thermal Soil Desorption in gas chromatography, including procedures for, and advantages of faster testing and analysis times, concurrent volatile and semi-volatile analysis, minimized sample manipulation, single gas (H 2 ) operation, and detection to the part-per billion levels

The interpretation of diagnostic tests

International Nuclear Information System (INIS)

Lamk, M.; Lamki, M.D.

1987-01-01

The progress of nuclear and other diagnostic imaging is near rampant. With almost every issue of the major journals in this field, a new diagnostic test, or at least a new utility of an old test is described. Before we accept these innovations, we have to have a clear understanding of the clinical performance of the test. The major criteria are the sensitivity and the specificity of the test. From these derived other statistical parameters such as accuracy or efficiency of that test; also, the receiver operating characteristic (ROC) curves may then be evaluated and used in comparison of different tests. When we know the prevalence of the disease tested in the population we are investigating, we can then derive the predictive value of a positive or a negative result. This introduction tries to explain these parameters to help the reader understand the literature dealing with the subject of efficacy of imaging procedures. It is not intended as a critical review of the literature on the subject or a comprehensive overview of the subject matter. The benefit derived from explaination of statistical concepts to physicians is documented in a recent publication. Explaination of these basic statistical parameters will be followed by a demonstration of the utility of multiple testing with these parameters. The reader is thereby introduced to relevant statistical concepts that must be grasped for full comprehension of published results of a new diagnostic imaging modality, or before clinical decision making

Diagnostic tests based on human basophils

DEFF Research Database (Denmark)

Kleine-Tebbe, Jörg; Erdmann, Stephan; Knol, Edward F

2006-01-01

-maximal responses, termed 'intrinsic sensitivity'. These variables give rise to shifts in the dose-response curves which, in a diagnostic setting where only a single antigen concentration is employed, may produce false-negative data. Thus, in order to meaningfully utilize the current basophil activation tests....... Diagnostic studies using CD63 or CD203c in hymenoptera, food and drug allergy are critically discussed. Basophil-based tests are indicated for allergy testing in selected cases but should only be performed by experienced laboratories....

Prenatal Genetic Diagnostic Tests

Science.gov (United States)

... are available for many inherited disorders. The main disadvantage is that diagnostic testing carries a very small ... chromosomes, arranged in order of size. Microarray: A technology that examines all of a person’s genes to ...

The diagnostic accuracy of serological tests for Lyme borreliosis in Europe

DEFF Research Database (Denmark)

Leeflang, M M G; Ang, C W; Berkhout, J

2016-01-01

-eight studies evaluating an Enzyme-Linked ImmunoSorbent assay (ELISA) or an immunoblot assay against a reference standard of clinical criteria were included. None of the studies had low risk of bias for all QUADAS-2 domains. Sensitivity was highly heterogeneous, with summary estimates: erythema migrans 50 % (95......BACKGROUND: Interpretation of serological assays in Lyme borreliosis requires an understanding of the clinical indications and the limitations of the currently available tests. We therefore systematically reviewed the accuracy of serological tests for the diagnosis of Lyme borreliosis in Europe....... We used a hierarchical summary ROC meta-regression method for the meta-analyses. Potential sources of heterogeneity were test-type, commercial or in-house, Ig-type, antigen type and study quality. These were added as covariates to the model, to assess their effect on test accuracy. RESULTS: Seventy...

Performance of chromatographic systems to model soil-water sorption.

Science.gov (United States)

Hidalgo-Rodríguez, Marta; Fuguet, Elisabet; Ràfols, Clara; Rosés, Martí

2012-08-24

A systematic approach for evaluating the goodness of chromatographic systems to model the sorption of neutral organic compounds by soil from water is presented in this work. It is based on the examination of the three sources of error that determine the overall variance obtained when soil-water partition coefficients are correlated against chromatographic retention factors: the variance of the soil-water sorption data, the variance of the chromatographic data, and the variance attributed to the dissimilarity between the two systems. These contributions of variance are easily predicted through the characterization of the systems by the solvation parameter model. According to this method, several chromatographic systems besides the reference octanol-water partition system have been selected to test their performance in the emulation of soil-water sorption. The results from the experimental correlations agree with the predicted variances. The high-performance liquid chromatography system based on an immobilized artificial membrane and the micellar electrokinetic chromatography systems of sodium dodecylsulfate and sodium taurocholate provide the most precise correlation models. They have shown to predict well soil-water sorption coefficients of several tested herbicides. Octanol-water partitions and high-performance liquid chromatography measurements using C18 columns are less suited for the estimation of soil-water partition coefficients. Copyright © 2012 Elsevier B.V. All rights reserved.

Evaluating Diagnostic Point-of-Care Tests in Resource-Limited Settings

Science.gov (United States)

Drain, Paul K; Hyle, Emily P; Noubary, Farzad; Freedberg, Kenneth A; Wilson, Douglas; Bishai, William; Rodriguez, William; Bassett, Ingrid V

2014-01-01

Diagnostic point-of-care (POC) testing is intended to minimize the time to obtain a test result, thereby allowing clinicians and patients to make an expeditious clinical decision. As POC tests expand into resource-limited settings (RLS), the benefits must outweigh the costs. To optimize POC testing in RLS, diagnostic POC tests need rigorous evaluations focused on relevant clinical outcomes and operational costs, which differ from evaluations of conventional diagnostic tests. Here, we reviewed published studies on POC testing in RLS, and found no clearly defined metric for the clinical utility of POC testing. Therefore, we propose a framework for evaluating POC tests, and suggest and define the term “test efficacy” to describe a diagnostic test’s capacity to support a clinical decision within its operational context. We also proposed revised criteria for an ideal diagnostic POC test in resource-limited settings. Through systematic evaluations, comparisons between centralized diagnostic testing and novel POC technologies can be more formalized, and health officials can better determine which POC technologies represent valuable additions to their clinical programs. PMID:24332389

[Diagnostic test scale SI5: Assessment of sacroiliac joint dysfunction].

Science.gov (United States)

Acevedo González, Juan C; Quintero Oliveros, Silvia

2015-01-01

Sacroiliac joint dysfunction is a known cause of low back pain. We think that a diagnostic score scale (SI5) may be performed to assess diagnostic utility of clinical signs of sacroiliac joint dysfunction. The primary aim of the present study was to conduct the pilot study of our new diagnostic score scale, the SI5, for sacroiliac joint syndrome. We reviewed the literature on clinical characteristics, diagnostic tests and imaging most commonly used in diagnosing sacroiliac joint dysfunction. Our group evaluated the diagnostic utility of these aspects and we used those considered most representative to develop the SI5 diagnostic scale. The SI5 scale was applied to 22 patients with low back pain; afterwards, the standard test for diagnosing this pathology (selective blockage of the SI joint) was also performed on these patients. The sensitivity and specificity for each sign were also assessed and the diagnostic scale called SI5 was then proposed, based on these data. The most sensitive clinical tests for diagnosing SI joint dysfunction were 2 patient-reported clinical characteristics, the Laguerre Test, sacroiliac rocking test and Yeomans test (greater than 80% sensitivity). The tests with greatest diagnostic specificity (>80%) were the Lewitt test, Piedallu test and Gillet test. The proposed SI5 test score scale showed sensitivity of 73% and specificity of 71%. Sacroiliac joint syndrome has been shown to produce low back pain frequently; however, the diagnostic value of examination tests for sacroiliac joint pain has been questioned by other authors. The pilot study on the SI5 diagnostic score scale showed good sensitivity and specificity. However, the process of statistical validation of the SI5 needs to be continued. Copyright © 2014 Sociedad Española de Neurocirugía. Published by Elsevier España. All rights reserved.

Systematic reviews of diagnostic test accuracy

DEFF Research Database (Denmark)

Leeflang, Mariska M G; Deeks, Jonathan J; Gatsonis, Constantine

2008-01-01

More and more systematic reviews of diagnostic test accuracy studies are being published, but they can be methodologically challenging. In this paper, the authors present some of the recent developments in the methodology for conducting systematic reviews of diagnostic test accuracy studies....... Restrictive electronic search filters are discouraged, as is the use of summary quality scores. Methods for meta-analysis should take into account the paired nature of the estimates and their dependence on threshold. Authors of these reviews are advised to use the hierarchical summary receiver...

Performance of the fully automated progesterone assays on the Abbott AxSYM and the Technicon Immuno 1 Analyser compared with the radioimmunoassay progesterone MAIA

International Nuclear Information System (INIS)

Reinsberg, J.; Jost, E.; Van der Ven, H.

1997-01-01

Test performance of two automated progesterone assays available on the immunoassay analysers Abbott AxSYM and Technicon Immuno 1, respectively, was evaluated in comparison with the radioimmunoassay Progesterone MAIA. For assessment of test performance imprecision, functional sensitivity and linearity of dilution was examined. Correlation with the manual radioimmunoassay was assessed using 122 serum samples over the range 0-110 nmol/L. Imprecision studies revealed for the AxSYM Progesterone within-run CV's of 1.8-6.4% and day-to-day CV's of 3.5-9.7% (concentration range 2.3-75 nmol/L); Immuno 1 Progesterone: within-run CV's 1.0-7.3%, day-to-day CV's 2.3-7.7% (concentration range 1.2-60 nmol/L). The functional sensitivity was <1.7 nmol/L for the AxSYM Progesterone and <1.1 nmol/L for the Immuno 1 Progesterone. With the AxSYM Progesterone the mean recovery after dilution from five samples was 102% (89-107%), from one sample only 69-80% was recovered; with the Immuno 1 Progesterone the mean recovery was 95% (80-105%). Despite of a quite good overall correlation (coefficients 0.972 and 0.981) the relationship of both assays to the Progesterone MAIA significantly deviate from linearity with a considerably higher slope within the lower concentration range. The relationship between the automated assays was linear over the entire concentration range (Immuno = 1.207 * AxSYM + 1; r = 0.986). The time to first result was 20 min for the AxSYM Progesterone, 45 min for the Immuno 1 Progesterone and 90 min for the Progesterone MAIA. The evaluated progesterone assays both exhibit an excellent precision and a high degree of sensitivity. They offer a rapid and flexible method for progesterone determination which may be especially useful for the monitoring of ovarian stimulation during in-vitro fertilization. (author)

Immuno-therapy of Acute Radiation Syndromes : Extracorporeal Immuno-Lympho-Plasmo-Sorption.

Science.gov (United States)

Popov, Dmitri; Maliev, Slava

Methods Results Summary and conclusions Introduction: Existing Medical Management of the Acute Radiation Syndromes (ARS) does not include methods of specific immunotherapy and active detoxication. Though the Acute Radiation Syndromes were defined as an acute toxic poisonous with development of pathological processes: Systemic Inflammatory Response Syndrome (SIRS), Toxic Multiple Organ Injury (TMOI), Toxic Multiple Organ Dysfunction Syndrome(TMODS), Toxic Multiple Organ Failure (TMOF). Radiation Toxins of SRD Group play an important role as the trigger mechanisms in development of the ARS clinical symptoms. Methods: Immuno-Lympho-Plasmo-Sorption is a type of Immuno-therapy which includes prin-ciples of immunochromato-graphy, plasmopheresis, and hemodialysis. Specific Antiradiation Antitoxic Antibodies are the active pharmacological agents of immunotherapy . Antiradia-tion Antitoxic Antibodies bind selectively to Radiation Neurotoxins, Cytotoxins, Hematotox-ins and neutralize their toxic activity. We have developed the highly sensitive method and system for extracorporeal-immune-lypmh-plasmo-sorption with antigen-specific IgG which is clinically important for treatment of the toxic and immunologic phases of the ARS. The method of extracorporeal-immune-lypmh-plasmo-sorption includes Antiradiation Antitoxic Antibodies (AAA) immobilized on microporous polymeric membranes with a pore size that is capable to provide diffusion of blood-lymph plasma. Plasma of blood or lymph of irradiated mammals contains Radiation Toxins (RT) that have toxic and antigenic properties. Radiation Toxins are Antigen-specific to Antitoxic blocking antibodies (Immunoglobulin G). Plasma diffuses through membranes with immobilized AAA and AA-antibodies bind to the polysaccharide chain of tox-ins molecules and complexes of AAA-RT that are captured on membrane surfaces. RT were removed from plasma. Re-transfusion of plasma of blood and lymph had been provided. We show a statistical significant

Cellular and humoral immuno-stimulatory effects of diagnostic doses of X-rays in BALB/c mice

International Nuclear Information System (INIS)

Mortazavi, S.M.J.; Jafar-Zadeh, A.; Khosravi, M.H.; Mehdipour, L.A.; Behnejad, B.B.

2006-01-01

Objective: The immunosuppressive effects of high doses of ionizing radiation have long been known, while researchers know less about the effects of low dose radiation on the immune system. Recently, in human and experimental animal models it has been reported that low dose radiation may have immuno-stimulatory effects. The aim of this study was to evaluate the effects of low doses of diagnostic doses of X-rays on cell mediated and humoral immune responses in a Balb/c animal model. Materials and Methods: Using a conventional Villa radiography machine, three groups of male Balb/c mice were exposed one, two and three times to 30 mGy of X-rays. The measured surface dose was equal to the dose of a single view lateral lumbar radiography. Two to four hours after irradiation, the delayed type hypersensitivity (DTH) and humoral responses to sheep red blood cell (SRBC) were measured and compared to the responses of sham and control groups. Results: The mean titer of anti-SRBC antibodies in two-times irradiated (74.66± 26.12 ) and three-times irradiated (128 ± 70.1) groups were significantly higher than those of non-irradiated (26.66 ± 8.26) or sham irradiated (28.8 ± 20.86) group (p<0.001). However, no significant differences were observed between the mean titer of anti-SRBC antibodies in one-time irradiated (22.4 ± 8.76) and either non-irradiated or sham irradiated groups. Similarly, comparing DTH responses showed that the differences between either two-times irradiated (12.2 ± 3.9 ) or three times-irradiated (6.9 ± 3.7) and non-irradiated (4 ± 0.2) or sham irradiated (4.3 ± 3) groups was statistically significant (p<0.001). Conclusion: Theses results show that two-times and three-times irradiated mice demonstrate significant stimulatory effects on both DTH and antibody responses. However, one-time irradiated animals did not exhibit any bio- positive effect on DTH and humoral responses. Moreover, no statistically significant difference was observed between the DTH

The use of irradiated food for immuno-suppressed hospital patients

International Nuclear Information System (INIS)

Pryke, D.C.

1994-01-01

The treatment of leukaemia and other forms of haematological malignancies involves destruction of the bone marrow followed by bone-marrow transplant. This results in patients becoming severely immuno-suppressed. Other diseases result in a similar condition, most notably Acquired Immuno-Deficiency Syndrome (AIDS). Irradiation using radioactive sources or machines has been proposed as a method for preparing foods for immuno-suppressed patients and other high risk groups. Doses of around 30 kGy ensure a total sterility whilst a dose of 10 kGy (the recommended maximum for food available to the general public) results in a significant reduction in the number of pathogenic microorganisms. Irradiation has a number of advantages over other processing methods, in particular that flavour, texture and nutritional changes are limited. This is important as patients are often in a compromised state and need clinical assistance in returning to normal eating habits. In recognition of the potential of irradiated foods for hospital patients this use has been specifically exempted from regulatory control in the UK. This paper reviews the experience in the UK of irradiation-sterilized foods in hospitals. It was found that for practical reasons use is currently restricted. The future prospects for food irradiated at non-sterilized doses are also considered. It is concluded that as well as providing greater choice for consumers (high risk and the general public as a whole) irradiated foods could extend and improved the diets of immuno-suppressed hospital patients; this could be an important factor in recovery. (author)

The gas-chromatographic and gas-chromatographic-mass-spectrometric identification of halogen-containing organic compounds

Science.gov (United States)

Gidaspov, B. V.; Zenkevich, I. G.; Rodin, A. A.

1989-09-01

The problem of identifying halogen-containing organic compounds in their gas-chromatographic and gas-chromatographic-mass-spectrometric (GC-MS) determination in different materials has been examined. Particular attention has been paid not to the complete characterisation of methods for carrying out this analysis but to the most important problem of increasing the selectivity at the stages of sampling, separation, and interpretation of the gas-chromatographic and GC-MS information. The bibliography contains 292 references.

GMR sensors and magnetic nanoparticles for immuno-chromatographic assays

International Nuclear Information System (INIS)

Marquina, C.; Teresa, J.M. de; Serrate, D.; Marzo, J.; Cardoso, F.A.; Saurel, D.; Cardoso, S.; Freitas, P.P.

2012-01-01

Conventional tests based on immunorecognition and on the use of coloured colloidal particles have still some drawbacks that limit their use: they do not provide a quantitative determination of the analyte, and their sensitivity is limited. Our strategy to overcome these disadvantages consists in the use of superparamagnetic core-shell nanoparticles to tag the analyte. The use of these magnetic labels allows us to quantify the amount of analyte present in our sample with a very high sensitivity, detecting their magnetic response by means of the suitable magnetic sensor. Our method is based on measuring the magnetoresistive response of a spin-valve giant magnetoresistive (GMR) sensor placed in proximity to the magnetic nanoparticles present in the lateral flow strip. Here, a brief description of our prototype and of the measurement procedure will be presented, as well as preliminary assays using our biosensor to detect the hCG pregnancy hormone in a solution. A crucial aspect to take into account in order to increase the sensitivity is the proper functionalisation of the nanoparticle shell, in order to achieve an oriented immobilisation of the antibodies to be used in the immunorecognition process. Several strategies to further increase the sensor sensitivity are suggested.

GMR sensors and magnetic nanoparticles for immuno-chromatographic assays

Energy Technology Data Exchange (ETDEWEB)

Marquina, C., E-mail: clara@unizar.es [Instituto de Ciencia de Materiales de Aragon ICMA, CSIC-Universidad de Zaragoza, C/Pedro Cerbuna 12, 50009 Zaragoza (Spain); Departamento de Fisica de la Materia Condensada, Universidad de Zaragoza, C/Pedro Cerbuna 12, 50009 Zaragoza (Spain); Teresa, J.M. de [Instituto de Ciencia de Materiales de Aragon ICMA, CSIC-Universidad de Zaragoza, C/Pedro Cerbuna 12, 50009 Zaragoza (Spain); Departamento de Fisica de la Materia Condensada, Universidad de Zaragoza, C/Pedro Cerbuna 12, 50009 Zaragoza (Spain); Serrate, D. [Departamento de Fisica de la Materia Condensada, Universidad de Zaragoza, C/Pedro Cerbuna 12, 50009 Zaragoza (Spain); Instituto de Nanociencia de Aragon (INA), Universidad de Zaragoza, C/Mariano Esquillor s/n, 50018 Zaragoza (Spain); Marzo, J. [Instituto de Ciencia de Materiales de Aragon ICMA, CSIC-Universidad de Zaragoza, C/Pedro Cerbuna 12, 50009 Zaragoza (Spain); Cardoso, F.A. [INESC-MN-Instituto de Engenharia de Sistemas e Computadores-Microsistemas e Nanotecnologias and IN-Institute of Nanoscience and Nanotechnology, Rua Alves Redol 9, 1000-029 Lisbon (Portugal); Saurel, D. [Instituto de Nanociencia de Aragon (INA), Universidad de Zaragoza, C/Mariano Esquillor s/n, 50018 Zaragoza (Spain); Cardoso, S.; Freitas, P.P. [INESC-MN-Instituto de Engenharia de Sistemas e Computadores-Microsistemas e Nanotecnologias and IN-Institute of Nanoscience and Nanotechnology, Rua Alves Redol 9, 1000-029 Lisbon (Portugal); and others

2012-10-15

Conventional tests based on immunorecognition and on the use of coloured colloidal particles have still some drawbacks that limit their use: they do not provide a quantitative determination of the analyte, and their sensitivity is limited. Our strategy to overcome these disadvantages consists in the use of superparamagnetic core-shell nanoparticles to tag the analyte. The use of these magnetic labels allows us to quantify the amount of analyte present in our sample with a very high sensitivity, detecting their magnetic response by means of the suitable magnetic sensor. Our method is based on measuring the magnetoresistive response of a spin-valve giant magnetoresistive (GMR) sensor placed in proximity to the magnetic nanoparticles present in the lateral flow strip. Here, a brief description of our prototype and of the measurement procedure will be presented, as well as preliminary assays using our biosensor to detect the hCG pregnancy hormone in a solution. A crucial aspect to take into account in order to increase the sensitivity is the proper functionalisation of the nanoparticle shell, in order to achieve an oriented immobilisation of the antibodies to be used in the immunorecognition process. Several strategies to further increase the sensor sensitivity are suggested.

Application of recombinant antigen 5 allergens from seven allergy-relevant Hymenoptera species in diagnostics.

Science.gov (United States)

Schiener, M; Eberlein, B; Moreno-Aguilar, C; Pietsch, G; Serrano, P; McIntyre, M; Schwarze, L; Russkamp, D; Biedermann, T; Spillner, E; Darsow, U; Ollert, M; Schmidt-Weber, C B; Blank, S

2017-01-01

Hymenoptera stings can cause severe anaphylaxis in untreated venom-allergic patients. A correct diagnosis regarding the relevant species for immunotherapy is often hampered by clinically irrelevant cross-reactivity. In vespid venom allergy, cross-reactivity between venoms of different species can be a diagnostic challenge. To address immunological IgE cross-reactivity on molecular level, seven recombinant antigens 5 of the most important Vespoidea groups were assessed by different diagnostic setups. The antigens 5 of yellow jackets, hornets, European and American paper wasps, fire ants, white-faced hornets, and Polybia wasps were recombinantly produced in insect cells, immunologically and structurally characterized, and their sIgE reactivity assessed by ImmunoCAP, ELISA, cross-inhibition, and basophil activation test (BAT) in patients with yellow jacket or Polistes venom allergy of two European geographical areas. All recombinant allergens were correctly folded and structural models and patient reactivity profiles suggested the presence of conserved and unique B-cell epitopes. All antigens 5 showed extensive cross-reactivity in sIgE analyses, inhibition assays, and BAT. This cross-reactivity was more pronounced in ImmunoCAP measurements with venom extracts than in sIgE analyses with recombinant antigens 5. Dose-response curves with the allergens in BAT allowed a differentiated individual dissection of relevant sensitization. Due to extensive cross-reactivity in various diagnostic settings, antigens 5 are inappropriate markers for differential sIgE diagnostics in vespid venom allergy. However, the newly available antigens 5 from further vespid species and the combination of recombinant allergen-based sIgE measurements with BAT represents a practicable way to diagnose clinically relevant sensitization in vespid venom allergy. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Understanding the properties of diagnostic tests - Part 2: Likelihood ratios.

Science.gov (United States)

Ranganathan, Priya; Aggarwal, Rakesh

2018-01-01

Diagnostic tests are used to identify subjects with and without disease. In a previous article in this series, we examined some attributes of diagnostic tests - sensitivity, specificity, and predictive values. In this second article, we look at likelihood ratios, which are useful for the interpretation of diagnostic test results in everyday clinical practice.

A novel bedside diagnostic test for methanol poisoning using dry chemistry for formate.

Science.gov (United States)

Hovda, Knut Erik; Gadeholt, Gaut; Evtodienko, Vladimir; Jacobsen, Dag

2015-11-01

The standard diagnostic approach to methanol poisoning is chromatographic measurement of methanol on centrally placed stationary equipment. Methanol poisoning in places where such equipment is unavailable is thus often not diagnosed. Methanol is metabolized to a toxic metabolite, formate; the presence of this compound indicates methanol poisoning. We have developed an enzymatic test for formate and modified it into a portable dry chemistry system that could be used anywhere. The method consists of two enzymatic steps: Formation of NADH from NAD by formate dehydrogenase, and subsequent use of NADH as a reductant of a tetrazolium into a formazan dye that can be quantified photometrically or visually. The photometer gave a good correlation of R(2) = 0.9893 in serum and R(2) = 0.9949 in whole blood, showing an instrumental detection limit of less than 1 mM (4.5 mg/dL). The visual readings showed a correlation of R(2) = 0.8966. Users experienced some difficulty in separating the negative control from the low positives. We have documented the feasibility of an affordable formate strip test for bedside diagnosis of methanol poisoning and for screening of metabolic acidosis of unknown origin. Visual reading is possible, but a reader will improve reliability at lower levels of formate. Future studies are necessary to study the sensitivity and specificity towards other causes of metabolic acidosis and other acids present in human blood.

The current preference for the immuno-analytical ELISA method for quantitation of steroid hormones (endocrine disruptor compounds) in wastewater in South Africa.

Science.gov (United States)

Manickum, Thavrin; John, Wilson

2015-07-01

The availability of national test centers to offer a routine service for analysis and quantitation of some selected steroid hormones [natural estrogens (17-β-estradiol, E2; estrone, E1; estriol, E3), synthetic estrogen (17-α-ethinylestradiol, EE2), androgen (testosterone), and progestogen (progesterone)] in wastewater matrix was investigated; corresponding internationally used chemical- and immuno-analytical test methods were reviewed. The enzyme-linked immunosorbent assay (ELISA) (immuno-analytical technique) was also assessed for its suitability as a routine test method to quantitate the levels of these hormones at a sewage/wastewater treatment plant (WTP) (Darvill, Pietermaritzburg, South Africa), over a 2-year period. The method performance and other relevant characteristics of the immuno-analytical ELISA method were compared to the conventional chemical-analytical methodology, like gas/liquid chromatography-mass spectrometry (GC/LC-MS), and GC-LC/tandem mass spectrometry (MSMS), for quantitation of the steroid hormones in wastewater and environmental waters. The national immuno-analytical ELISA technique was found to be sensitive (LOQ 5 ng/L, LOD 0.2-5 ng/L), accurate (mean recovery 96%), precise (RSD 7-10%), and cost-effective for screening and quantitation of these steroid hormones in wastewater and environmental water matrix. A survey of the most current international literature indicates a fairly equal use of the LC-MS/MS, GC-MS/MS (chemical-analytical), and ELISA (immuno-analytical) test methods for screening and quantitation of the target steroid hormones in both water and wastewater matrix. Internationally, the observed sensitivity, based on LOQ (ng/L), for the steroid estrogens E1, E2, EE2, is, in decreasing order: LC-MSMS (0.08-9.54) > GC-MS (1) > ELISA (5) (chemical-analytical > immuno-analytical). At the national level, the routine, unoptimized chemical-analytical LC-MSMS method was found to lack the required sensitivity for meeting environmental

The indication area of a diagnostic test. Part I--discounting gain and loss in diagnostic certainty

NARCIS (Netherlands)

Stalpers, Lukas J. A.; Nelemans, Patty J.; Geurts, Sandra M. E.; Jansen, Erik; de Boer, Peter; Verbeek, André L. M.

2015-01-01

Test performance is conventionally expressed by gain in diagnostic certainty. We propose net diagnostic gain and indication area as more appropriate measures of test performance; then, the loss in certainty due to misclassification and the information of "no test" would be performed are taken into

ELISA and ImmunoStrip® for detection of Phytophthora ramorum, P. kernoviae, and other Phytophthora species

Science.gov (United States)

Francisco J. Avila; Barbara Schoedel; Z. Gloria Abad; Michael D. Coffey; Cheryl Blomquist

2009-01-01

The goal of this work was to develop improved tools for the detection of Phytophthora ramorum and P. kernoviae for field and the laboratory use. ImmunoStrip® and ELISA were selected as the test formats for development. Presently, the diagnosis of sudden oak death (SOD) in the national survey of P. ramorum ...

Antimicrobial susceptibility testing by Australian veterinary diagnostic laboratories.

Science.gov (United States)

Hardefeldt, L Y; Marenda, M; Crabb, H; Stevenson, M A; Gilkerson, J R; Billman-Jacobe, H; Browning, G F

2018-04-01

The national strategy for tackling antimicrobial resistance highlights the need for antimicrobial stewardship in veterinary practice and for surveillance of antimicrobial susceptibility in veterinary pathogens. Diagnostic laboratories have an important role in facilitating both of these processes, but it is unclear whether data from veterinary diagnostic laboratories are similar enough to allow for compilation and if there is consistent promotion of appropriate antimicrobial use embedded in the approaches of different laboratories to susceptibility testing. A cross-sectional study of antimicrobial susceptibility testing and reporting procedures by Australian veterinary diagnostic laboratories was conducted in 2017 using an online questionnaire. All 18 veterinary diagnostic laboratories in Australia completed the questionnaire. Kirby-Bauer disc diffusion was the method predominantly used for antimicrobial susceptibility testing and was used to evaluate 86% of all isolates, although two different protocols were used across the 18 laboratories (CLSI 15/18, CDS 3/18). Minimum inhibitory concentrations were never reported by 61% of laboratories. Common isolates were consistently reported on across all species, except for gram-negative isolates in pigs, for which there was some variation in the approach to reporting. There was considerable diversity in the panels of antimicrobials used for susceptibility testing on common isolates and no consistency was apparent between laboratories for any bacterial species. We recommend that nationally agreed and consistent antimicrobial panels for routine susceptibility testing should be developed and a uniform set of guidelines should be adopted by veterinary diagnostic laboratories in Australia. © 2018 Australian Veterinary Association.

Immuno-modulatory properties of prebiotics extracted from Vernonia ...

African Journals Online (AJOL)

Methods: The immuno-modulatory potential was evaluated by monitoring the effects of oral administration of the extract on immunological, haematological and lipid profiles of Rattus norvegicus, while the prebiotic components were identified by thin layer chromatography (TLC), following liquid-liquid fractionation of the ...

The impact of new trends in POCTs for companion diagnostics, non-invasive testing and molecular diagnostics.

Science.gov (United States)

Huckle, David

2015-06-01

Point-of-care diagnostics have been slowly developing over several decades and have taken on a new importance in current healthcare delivery for both diagnostics and development of new drugs. Molecular diagnostics have become a key driver of technology change and opened up new areas in companion diagnostics for use alongside pharmaceuticals and in new clinical approaches such as non-invasive testing. Future areas involving smartphone and other information technology advances, together with new developments in molecular biology, microfluidics and surface chemistry are adding to advances in the market. The focus for point-of-care tests with molecular diagnostic technologies is focused on advancing effective applications.

Cytokine-induced 'bystander' senescence in DDR and immuno-surveillance

Czech Academy of Sciences Publication Activity Database

Hodný, Zdeněk; Hubáčková, Soňa; Bartek, Jiří

2013-01-01

Roč. 4, č. 10 (2013), s. 1552-1553 ISSN 1949-2553 Institutional support: RVO:68378050 Keywords : cell senescence * cytokines * immuno-surveillance Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 6.627, year: 2013

Immunochromatographic diagnostic test analysis using Google Glass.

Science.gov (United States)

Feng, Steve; Caire, Romain; Cortazar, Bingen; Turan, Mehmet; Wong, Andrew; Ozcan, Aydogan

2014-03-25

We demonstrate a Google Glass-based rapid diagnostic test (RDT) reader platform capable of qualitative and quantitative measurements of various lateral flow immunochromatographic assays and similar biomedical diagnostics tests. Using a custom-written Glass application and without any external hardware attachments, one or more RDTs labeled with Quick Response (QR) code identifiers are simultaneously imaged using the built-in camera of the Google Glass that is based on a hands-free and voice-controlled interface and digitally transmitted to a server for digital processing. The acquired JPEG images are automatically processed to locate all the RDTs and, for each RDT, to produce a quantitative diagnostic result, which is returned to the Google Glass (i.e., the user) and also stored on a central server along with the RDT image, QR code, and other related information (e.g., demographic data). The same server also provides a dynamic spatiotemporal map and real-time statistics for uploaded RDT results accessible through Internet browsers. We tested this Google Glass-based diagnostic platform using qualitative (i.e., yes/no) human immunodeficiency virus (HIV) and quantitative prostate-specific antigen (PSA) tests. For the quantitative RDTs, we measured activated tests at various concentrations ranging from 0 to 200 ng/mL for free and total PSA. This wearable RDT reader platform running on Google Glass combines a hands-free sensing and image capture interface with powerful servers running our custom image processing codes, and it can be quite useful for real-time spatiotemporal tracking of various diseases and personal medical conditions, providing a valuable tool for epidemiology and mobile health.

A novel immuno-gold labeling protocol for nanobody-based detection of HER2 in breast cancer cells using immuno-electron microscopy

NARCIS (Netherlands)

Kijanka, M; van Donselaar, E G; Müller, W H; Dorresteijn, B; Popov-Celeketic, Dusan; El Khattabi, M; Verrips, C T; van Bergen En Henegouwen, P M P; Post, J A

Immuno-electron microscopy is commonly performed with the use of antibodies. In the last decade the antibody fragment indicated as nanobody (VHH or single domain antibody) has found its way to different applications previously done with conventional antibodies. Nanobodies can be selected to bind

A WAO - ARIA - GA²LEN consensus document on molecular-based allergy diagnostics.

Science.gov (United States)

Canonica, Giorgio Walter; Ansotegui, Ignacio J; Pawankar, Ruby; Schmid-Grendelmeier, Peter; van Hage, Marianne; Baena-Cagnani, Carlos E; Melioli, Giovanni; Nunes, Carlos; Passalacqua, Giovanni; Rosenwasser, Lanny; Sampson, Hugh; Sastre, Joaquin; Bousquet, Jean; Zuberbier, Torsten

2013-10-03

Molecular-based allergy (MA) diagnostics is an approach used to map the allergen sensitization of a patient at a molecular level, using purified natural or recombinant allergenic molecules (allergen components) instead of allergen extracts. Since its introduction, MA diagnostics has increasingly entered routine care, with currently more than 130 allergenic molecules commercially available for in vitro specific IgE (sIgE) testing.MA diagnostics allows for an increased accuracy in allergy diagnosis and prognosis and plays an important role in three key aspects of allergy diagnosis: (1) resolving genuine versus cross-reactive sensitization in poly-sensitized patients, thereby improving the understanding of triggering allergens; (2) assessing, in selected cases, the risk of severe, systemic versus mild, local reactions in food allergy, thereby reducing unnecessary anxiety for the patient and the need for food challenge testing; and (3) identifying patients and triggering allergens for specific immunotherapy (SIT).Singleplex and multiplex measurement platforms are available for MA diagnostics. The Immuno-Solid phase Allergen Chip (ISAC) is the most comprehensive platform currently available, which involves a biochip technology to measure sIgE antibodies against more than one hundred allergenic molecules in a single assay. As the field of MA diagnostics advances, future work needs to focus on large-scale, population-based studies involving practical applications, elucidation and expansion of additional allergenic molecules, and support for appropriate test interpretation. With the rapidly expanding evidence-base for MA diagnosis, there is a need for allergists to keep abreast of the latest information. The aim of this consensus document is to provide a practical guide for the indications, determination, and interpretation of MA diagnostics for clinicians trained in allergology.

Specific IgE Antibodies in Young Children with Atopic Dermatitis--Correlation of Multiple Allergen Simultaneous Immunoblot Test and ImmunoCap System.

Science.gov (United States)

Konopka, Ewa; Ceregra, Aldona; Maciorkowska, Elzbieta; Surowska, Barbara; Trojanowska, Ilona; Roszko-Kirpsza, Izabela; Cukrowska, Bozena

2016-01-01

Sensitization to food allergens is a common condition in pediatric atopic dermatitis (AD). Recently, the multiple allergen simultaneous test (MAST) allowing for a comprehensive assessment of atopy has been developed, but the usefulness in young AD children is not known. The aim of this study was to determine IgE specificity in AD children using MAST and to compare the results for selected food allergens with the reference ImmunoCap system. The study enrolled 50 children up to 2 years old with a diagnosis of AD. IgE antibodies were measured with the MAST-immunoblots. Children with specific IgE levels ≥ 0.35 kU/L were identified as sensitized to allergens. Most often children were sensitized to food allergens (egg white and yolk, hazelnuts, potato, cow's milk proteins, wheat flour, codfish, and soybean), but a high percentage of them also had IgE antibodies against house dust mites (12%), grass (10%), and birch (10%). Eight percent of children were sensitized to domestic animals (cats and dogs). Almost perfect (kappa index 0.8 - 1.0) and substantial (kappa index 0.6 - 0.8) agreement between MAST and ImmunoCap was found for food allergens except codfish. Pearson's analysis of antibody classes showed a very strong correlation between two methods (r = 0.8 - 1.0) for egg white, hazelnuts, potato, cow's milk proteins, wheat flour, and soybean, and a strong correlation (r = 0.6 - 0.79) was observed for peanut, egg yolk, and codfish. The study showed the frequent occurrence of IgE antibodies against food and airborne and animal allergens in young AD children and confirmed the usefulness of MAST-immunoblots for screening of sensitization in pediatric patients.

Dilution testing using rapid diagnostic tests in a HIV diagnostic algorithm: a novel alternative for confirmation testing in resource limited settings.

Science.gov (United States)

Shanks, Leslie; Siddiqui, M Ruby; Abebe, Almaz; Piriou, Erwan; Pearce, Neil; Ariti, Cono; Masiga, Johnson; Muluneh, Libsework; Wazome, Joseph; Ritmeijer, Koert; Klarkowski, Derryck

2015-05-14

Current WHO testing guidelines for resource limited settings diagnose HIV on the basis of screening tests without a confirmation test due to cost constraints. This leads to a potential risk of false positive HIV diagnosis. In this paper, we evaluate the dilution test, a novel method for confirmation testing, which is simple, rapid, and low cost. The principle of the dilution test is to alter the sensitivity of a rapid diagnostic test (RDT) by dilution of the sample, in order to screen out the cross reacting antibodies responsible for falsely positive RDT results. Participants were recruited from two testing centres in Ethiopia where a tiebreaker algorithm using 3 different RDTs in series is used to diagnose HIV. All samples positive on the initial screening RDT and every 10th negative sample underwent testing with the gold standard and dilution test. Dilution testing was performed using Determine™ rapid diagnostic test at 6 different dilutions. Results were compared to the gold standard of Western Blot; where Western Blot was indeterminate, PCR testing determined the final result. 2895 samples were recruited to the study. 247 were positive for a prevalence of 8.5 % (247/2895). A total of 495 samples underwent dilution testing. The RDT diagnostic algorithm misclassified 18 samples as positive. Dilution at the level of 1/160 was able to correctly identify all these 18 false positives, but at a cost of a single false negative result (sensitivity 99.6 %, 95 % CI 97.8-100; specificity 100 %, 95 % CI: 98.5-100). Concordance between the gold standard and the 1/160 dilution strength was 99.8 %. This study provides proof of concept for a new, low cost method of confirming HIV diagnosis in resource-limited settings. It has potential for use as a supplementary test in a confirmatory algorithm, whereby double positive RDT results undergo dilution testing, with positive results confirming HIV infection. Negative results require nucleic acid testing to rule out false

Quantifying the Accuracy of a Diagnostic Test or Marker

NARCIS (Netherlands)

Linnet, Kristian; Bossuyt, Patrick M. M.; Moons, Karel G. M.; Reitsma, Johannes B. R.

2012-01-01

BACKGROUND: In recent years, increasing focus has been directed to the methodology for evaluating (new) tests or biomarkers. A key step in the evaluation of a diagnostic test is the investigation into its accuracy. CONTENT: We reviewed the literature on how to assess the accuracy of diagnostic

Systemic study on the safety of immuno-deficient nude mice treated by atmospheric plasma-activated water

Science.gov (United States)

Dehui, XU; Qingjie, CUI; Yujing, XU; Bingchuan, WANG; Miao, TIAN; Qiaosong, LI; Zhijie, LIU; Dingxin, LIU; Hailan, CHEN; Michael, G. KONG

2018-04-01

Cold atmospheric-pressure plasma is a new technology, widely used in many fields of biomedicine, especially in cancer treatment. Cold plasma can selectively kill a variety of tumor cells, and its biological safety in clinical trials is also very important. In many cases, the patient’s immune level is relatively low, so we first studied the safety assessment of plasma treatment in an immuno-compromised animal model. In this study, we examined the safety of immuno-deficient nude mice by oral lavage treatment of plasma-activated water, and studied the growth status, main organs and blood biochemical indexes. Acute toxicity test results showed that the maximum dose of plasma treatment for 15 min had no lethal effect and other acute toxicity. There were no significant changes in body weight and survival status of mice after 2 min and 4 min of plasma-activated water (PAW) treatment for 2 weeks. After treatment, the major organs, including heart, liver, spleen, lung and kidney, were not significantly changed in organ coefficient and tissue structure. Blood biochemical markers showed that blood neutrophils and mononuclear cells were slightly increased, and the others remained unchanged. Liver function, renal function, electrolytes, glucose metabolism and lipid metabolism were not affected by different doses of PAW treatment. The above results indicate that PAW treatment can be used to treat immuno-deficient nude mice without significant safety problems.

Influence of column type and chromatographic conditions on the ion-exchange chromatography of immunoglobulins.

Science.gov (United States)

Yang, Y B; Harrison, K

1996-08-30

Immunoglobulins are often purified by affinity chromatography. However, this technique is costly, can result in poor resolution for subclasses (or is only group specific), and leads to possible leaching of contaminants into the purified products. Ion-exchange chromatography has shown great potential and has found an increased usage in the purification of immunoglobulins. The aim of this study is to further understand the separation mechanism with emphasis on the influence of column type and chromatographic conditions on the peak shape, selectivity and changes in the elution patterns. Included are strong cation-exchange, strong anion-exchange and weak anion-exchange columns. Five immunoglobulin G antibodies were used as test probes. Some sera and ascites were also used in the study. Among the chromatographic conditions examined were mobile phase pH, buffer type, buffer concentration, gradient rate, and column temperature. Significant differences in the chromatographic behavior (elution pattern, peak shape and selectivity) of the test samples are discussed in regard to the column type and the chromatographic conditions.

[The immuno-endocrine system. A new endocrine theory: the problem of the packed transport].

Science.gov (United States)

Csaba, György

2011-05-15

Since the eighties of the last century hormone content was justified in immune cells (lymphocytes, granulocytes, monocytes, macrophages and mast cells), which produce, store and secrete these hormones. Although the amount of these materials in immune cells is relatively small, the mass of the producers (immune cells) is so large, that the phenomenon must be considered from endocrinological point of view, underlying the important differences between the "classical" and immuno-endocrine systems. Cells of the classic (built-in) endocrine system are mono-producers, while immune cells can synthesize many types of hormones (polyproducers). In addition, these cells can transport the whole hormone-producing machinery to the site of need, producing a local effect. This can be observed, for example, in the case of endorphin producing immune cells during inflammation and during early pregnancy around the chorionic villi. Hormone producing immune cells also have receptors for many hormones, so that they are poly-receivers. Via hormone producing and receiving capacity there is a bidirectional connection between the neuro-endocrine and immuno-endocrine systems. In addition, there is a network inside the immuno-endocrine system. The packed transport theory attempts to explain the mechanism and importance of the immuno-endocrine system.

Local Sensitivity and Diagnostic Tests

NARCIS (Netherlands)

Magnus, J.R.; Vasnev, A.L.

2004-01-01

In this paper we confront sensitivity analysis with diagnostic testing.Every model is misspecified, but a model is useful if the parameters of interest (the focus) are not sensitive to small perturbations in the underlying assumptions. The study of the e ect of these violations on the focus is

Malaria in immuno-suppressed individuals on antiretroviral therapy ...

African Journals Online (AJOL)

Malaria in immuno-suppressed individuals on antiretroviral therapy (ART) in north-central Nigeria. C.R. Pam, B.T. Abubakar, G.O. Inwang, G.A. Amuga. Abstract. The immune deficiency caused by HIV infection reduces the immune response to malaria parasitaemia and therefore leads to an increased frequency of clinical ...

DiagTest3Grp: An R Package for Analyzing Diagnostic Tests with Three Ordinal Groups

Directory of Open Access Journals (Sweden)

Jingqin Luo

2012-10-01

Full Text Available Medical researchers endeavor to identify potentially useful biomarkers to develop marker-based screening assays for disease diagnosis and prevention. Useful summary measures which properly evaluate the discriminative ability of diagnostic markers are critical for this purpose. Literature and existing software, for example, R packages nicely cover summary measures for diagnostic markers used for the binary case (e.g., healthy vs. diseased. An intermediate population at an early disease stage usually exists between the healthy and the fully diseased population in many disease processes. Supporting utilities for three-group diagnostic tests are highly desired and important for identifying patients at the early disease stage for timely treatments. However, application packages which provide summary measures for three ordinal groups are currently lacking. This paper focuses on two summary measures of diagnostic accuracy—volume under the receiver operating characteristic surface and the extended Youden index, with three diagnostic groups. We provide the R package DiagTest3Grp to estimate, under both parametric and nonparametric assumptions, the two summary measures and the associated variances, as well as the optimal cut-points for disease diagnosis. An omnibus test for multiple markers and a Wald test for two markers, on independent or paired samples, are incorporated to compare diagnostic accuracy across biomarkers. Sample size calculation under the normality assumption can be performed in the R package to design future diagnostic studies. A real world application evaluating the diagnostic accuracy of neuropsychological markers for Alzheimer’s disease is used to guide readers through step-by-step implementation of DiagTest3Grp to demonstrate its utility.

Whole Genome Sequencing Increases Molecular Diagnostic Yield Compared with Current Diagnostic Testing for Inherited Retinal Disease.

Science.gov (United States)

Ellingford, Jamie M; Barton, Stephanie; Bhaskar, Sanjeev; Williams, Simon G; Sergouniotis, Panagiotis I; O'Sullivan, James; Lamb, Janine A; Perveen, Rahat; Hall, Georgina; Newman, William G; Bishop, Paul N; Roberts, Stephen A; Leach, Rick; Tearle, Rick; Bayliss, Stuart; Ramsden, Simon C; Nemeth, Andrea H; Black, Graeme C M

2016-05-01

To compare the efficacy of whole genome sequencing (WGS) with targeted next-generation sequencing (NGS) in the diagnosis of inherited retinal disease (IRD). Case series. A total of 562 patients diagnosed with IRD. We performed a direct comparative analysis of current molecular diagnostics with WGS. We retrospectively reviewed the findings from a diagnostic NGS DNA test for 562 patients with IRD. A subset of 46 of 562 patients (encompassing potential clinical outcomes of diagnostic analysis) also underwent WGS, and we compared mutation detection rates and molecular diagnostic yields. In addition, we compared the sensitivity and specificity of the 2 techniques to identify known single nucleotide variants (SNVs) using 6 control samples with publically available genotype data. Diagnostic yield of genomic testing. Across known disease-causing genes, targeted NGS and WGS achieved similar levels of sensitivity and specificity for SNV detection. However, WGS also identified 14 clinically relevant genetic variants through WGS that had not been identified by NGS diagnostic testing for the 46 individuals with IRD. These variants included large deletions and variants in noncoding regions of the genome. Identification of these variants confirmed a molecular diagnosis of IRD for 11 of the 33 individuals referred for WGS who had not obtained a molecular diagnosis through targeted NGS testing. Weighted estimates, accounting for population structure, suggest that WGS methods could result in an overall 29% (95% confidence interval, 15-45) uplift in diagnostic yield. We show that WGS methods can detect disease-causing genetic variants missed by current NGS diagnostic methodologies for IRD and thereby demonstrate the clinical utility and additional value of WGS. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Immuno-oncology combinations: raising the tail of the survival curve

International Nuclear Information System (INIS)

Harris, Samuel J.; Brown, Jessica; Lopez, Juanita; Yap, Timothy A.

2016-01-01

There have been exponential gains in immuno-oncology in recent times through the development of immune checkpoint inhibitors. Already approved by the U.S. Food and Drug Administration for advanced melanoma and non-small cell lung cancer, immune checkpoint inhibitors also appear to have significant antitumor activity in multiple other tumor types. An exciting component of immunotherapy is the durability of antitumor responses observed, with some patients achieving disease control for many years. Nevertheless, not all patients benefit, and efforts should thus now focus on improving the efficacy of immunotherapy through the use of combination approaches and predictive biomarkers of response and resistance. There are multiple potential rational combinations using an immunotherapy backbone, including existing treatments such as radiotherapy, chemotherapy or molecularly targeted agents, as well as other immunotherapeutics. The aim of such antitumor strategies will be to raise the tail on the survival curve by increasing the number of long term survivors, while managing any additive or synergistic toxicities that may arise with immunotherapy combinations. Rational trial designs based on a clear understanding of tumor biology and drug pharmacology remain paramount. This article reviews the biology underpinning immuno-oncology, discusses existing and novel immunotherapeutic combinations currently in development, the challenges of predictive biomarkers of response and resistance and the impact of immuno-oncology on early phase clinical trial design

Automated-process gas-chromatograph system for use in accelerated corrosion testing of HTGR core-support posts

International Nuclear Information System (INIS)

Harper, R.E.; Herndon, P.G.

1982-01-01

An automated-process gas chromatograph is the heart of a gaseous-impurities-analysis system developed for the Oak Ridge National Laboratory Core Support Performance Test, at which graphite core-support posts for high-temperature gas-cooled fission reactors are being subjected to accelerated corrosion tests under tightly controlled conditions of atmosphere and temperature. Realistic estimation of in-core corrosion rates is critically dependent upon the accurate measurement of low concentrations of CO, CO 2 , CH 4 , H 2 , and O 2 in the predominantly helium atmosphere. In addition, the capital and labor investment associated with each test puts a premium upon the reliability of the analytical system, as excessive downtime or failure to obtain accurate data would result in unacceptable costs and schedule delays. After an extensive survey of available measurement techniques, gas chromatography was chosen for reasons of accuracy, flexibility, good-performance record, and cost

Allergy Diagnosis in Children and Adults: Performance of a New Point-of-Care Device, ImmunoCAP Rapid.

Science.gov (United States)

Hedlin, Gunilla; Moreno, Carmen; Petersson, Carl Johan; Lilja, Gunnar; Toledano, Félix Lorente; García, Antonio Nieto; Nordvall, Lennart; Palmqvist, Mona; Rak, Sabina; Ahlstedt, Staffan; Borres, Magnus P

2009-07-01

: Allergy is a serious problem affecting approximately 1 of 4 individuals. The symptoms with and without allergy etiology are often difficult to distinguish from each other without using an IgE antibody test. The aim of this study was to investigate the performance of a new point-of-care (POC) test for IgE antibodies to relevant allergens in Europe. : IgE antibodies from children and adults with allergies recruited from allergy clinics in Sweden and Spain were analyzed for 10 allergens, suitable for the age groups, using the new POC test and ImmunoCAP laboratory test. The IgE antibody level best discriminating between positive and negative results (the cutoff point) for the different allergens of the POC test and the efficacy of the POC and the ImmunoCAP laboratory tests for diagnosing allergy compared with that of clinical diagnosis were investigated. : The estimated cutoffs for the different allergens in the POC test ranged from 0.70 to 2.56 kUA/L. Taking into account all positive allergen results in a given patient, the POC test could identify 95% of the patients with allergies. Seventy-eight percent of the allergen-specific physicians' diagnoses were identified and 97% of the negative ones. Most allergens exhibited good performance, identifying about 80% of clinically relevant cases. However, dog, mugwort, and wall pellitory would benefit from improvement. : The POC test will be a valuable adjunct in the identification or exclusion of patients with allergies and their most likely offending allergens, both in specialist and general care settings.

Sterile diets for the immuno-compromised: Is there a need?

Science.gov (United States)

Butterweck, Joseph S.

1995-02-01

There is a general misunderstanding in the radiation processing industry about the use of sterile diets in the medical profession. Sterile diets are used on a limited basis in hospitals that specialize in cancer treatment and organ transplants. These patients are severely immuno-compromised. There are many other patients that are immuno-compromised that do not require sterile diets. These patients may require a diet that is pathogen-free and are aslo "low-microbial diets". Nosocomial infections have become a major issue in US hospitals. The "infection control committee" is the focus group responsible to assure nosocomial infections incidence are below the hospital goals. Application of ionizing radiation to sterilize diets has not been chosen because the product is not available at a reasonable total cost. This paper will discuss the hospitals views.

Sterile diets for the immuno-comprised: is there a need?

International Nuclear Information System (INIS)

Butterweck, J.S.

1995-01-01

There is a general misunderstanding in the radiation processing industry about the use of sterile diets in the medical profession. Sterile diets are used on a limited basis in hospitals that specialize in cancer treatment and organ transplants. These patients are severely immuno-compromised. There are many other patients that are immuno-compromised that do not require sterile diets. These patients may require a diet that is pathogen-free and are also ''low-microbial diets''. Nosocomial infections have become a major issue in US hospitals. The ''infection control committee'' is the focus group responsible to assure nosocomial infections incidence are below the hospital goals. Application of ionizing radiation to sterilize diets has not been chosen because the product is not available at a reasonable total cost. This paper will discuss the hospitals views. (Author)

Research on technology of online gas chromatograph for SF6 decomposition products

Science.gov (United States)

Li, L.; Fan, X. P.; Zhou, Y. Y.; Tang, N.; Zou, Z. L.; Liu, M. Z.; Huang, G. J.

2017-12-01

Sulfur hexafluoride (SF6) decomposition products were qualitatively and quantitatively analyzed by several gas chromatographs in the laboratory. Test conditions and methods were selected and optimized to minimize and eliminate the SF6’ influences on detection of other trace components. The effective separation and detection of selected characteristic gases were achieved. And by comparison among different types of gas chromatograph, it was found that GPTR-S101 can effectively separate and detect SF6 decomposition products and has best the best detection limit and sensitivity. On the basis of GPTR-S101, online gas chromatograph for SF6decomposition products (GPTR-S201) was developed. It lays the foundation for further online monitoring and diagnosis of SF6.

Principles of qualitative analysis in the chromatographic context.

Science.gov (United States)

Valcárcel, M; Cárdenas, S; Simonet, B M; Carrillo-Carrión, C

2007-07-27

This article presents the state of the art of qualitative analysis in the framework of the chromatographic analysis. After establishing the differences between two main classes of qualitative analysis (analyte identification and sample classification/qualification) the particularities of instrumental qualitative analysis are commented on. Qualitative chromatographic analysis for sample classification/qualification through the so-called chromatographic fingerprint (for complex samples) or the volatiles profile (through the direct coupling headspace-mass spectrometry using the chromatograph as interface) is discussed. Next, more technical exposition of the qualitative chromatographic information is presented supported by a variety of representative examples.

Dissimilar association of conventional immuno-reactive versus specific insulin with cardiovascular risk factors : a consequence of proinsulinaemia?

NARCIS (Netherlands)

Grootenhuis, P A; Mooy, J M; Kostense, P J; Popp-Snijders, C; Bouter, L M; Heine, R J

In this study involving 365 non-diabetic elderly Caucasians, we examined the relationship of immuno-specific insulin (ISI), total immuno-reactive insulin (IRI), proinsulin (PI) and proinsulin-insulin ratio (PI:ISI) to serum high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), systolic

Reporting Diagnostic Scores in Educational Testing: Temptations, Pitfalls, and Some Solutions

Science.gov (United States)

Sinharay, Sandip; Puhan, Gautam; Haberman, Shelby J.

2010-01-01

Diagnostic scores are of increasing interest in educational testing due to their potential remedial and instructional benefit. Naturally, the number of educational tests that report diagnostic scores is on the rise, as are the number of research publications on such scores. This article provides a critical evaluation of diagnostic score reporting…

Automation of diagnostic genetic testing: mutation detection by cyclic minisequencing.

Science.gov (United States)

Alagrund, Katariina; Orpana, Arto K

2014-01-01

The rising role of nucleic acid testing in clinical decision making is creating a need for efficient and automated diagnostic nucleic acid test platforms. Clinical use of nucleic acid testing sets demands for shorter turnaround times (TATs), lower production costs and robust, reliable methods that can easily adopt new test panels and is able to run rare tests in random access principle. Here we present a novel home-brew laboratory automation platform for diagnostic mutation testing. This platform is based on the cyclic minisequecing (cMS) and two color near-infrared (NIR) detection. Pipetting is automated using Tecan Freedom EVO pipetting robots and all assays are performed in 384-well micro plate format. The automation platform includes a data processing system, controlling all procedures, and automated patient result reporting to the hospital information system. We have found automated cMS a reliable, inexpensive and robust method for nucleic acid testing for a wide variety of diagnostic tests. The platform is currently in clinical use for over 80 mutations or polymorphisms. Additionally to tests performed from blood samples, the system performs also epigenetic test for the methylation of the MGMT gene promoter, and companion diagnostic tests for analysis of KRAS and BRAF gene mutations from formalin fixed and paraffin embedded tumor samples. Automation of genetic test reporting is found reliable and efficient decreasing the work load of academic personnel.

Chromatographic separations of stereoisomers

Energy Technology Data Exchange (ETDEWEB)

Souter, R.W.

1985-01-01

This text covers both diastereomers and enantiomers; describes techniques for GC, HPLC, and other chromatographic methods; and tabulates results of various applications by both techniques and compound class. It provides current knowledge about separation mechanisms and interactions of asymmetric molecules, as well as experimental and commercial materials such as columns, instruments, and derivatization reagents. The contents also include stereoisomer separations by gas chromatography. Stereoisomer separations by high-performance liquid chromatography. Stereoisomer separations by other chromatographic techniques.

A web-based test of residents' skills in diagnostic radiology

International Nuclear Information System (INIS)

Finlay, K.; Norman, G.R.; Keane, D.R.; Stolberg, H.

2006-01-01

To develop an objective, Web-based tool for evaluating residents' knowledge of diagnostic radiology. We developed and tested a Web-based evaluation tool (the Diagnostic Radiology Skills Test) that consists of 3 tests, one in each of 3 domains of diagnostic radiology: chest, gastrointestinal, and musculoskeletal imaging. Each test comprises 30 cases representing a range of difficulty in the domain, including normal states, normal variants, typical cases of common diagnoses, and cases with more subtle findings. Cases are presented with a long menu of domain-specific possible diagnoses (response options), each coded for diagnostic appropriateness. Our subjects were 21 residents in postgraduate year (PGY) 2 to 5 and 11 experts in diagnostic radiology. Subjects accessed the tool via a Web site on our Web server. Residents test results were compared for reliability and validity across domain, case, and training level. In addition, results were correlated with commonly used established and objective evaluation tools. The tool demonstrated consistent monotonic improvement in performance with training level. It showed acceptable reliability in discriminating between residents at different performance levels, both within and across training levels (r = 0.53 within level and 0.69 across levels). Test results also had concurrent validity against the American College of Radiology In-Training Examination, a widely accepted objective assessment tool (r = 0.65, P < 0.01), and 2 Objective Structured Clinical Examinations (OSCEs) focusing on diagnostic skills (r = 0.78 and r 0.69, P < 0.01, respectively). Our study demonstrates the feasibility of a Web-based, standardized, objective assessment method for evaluating residents' performance. (author)

Predictors of Inappropriate Use of Diagnostic Tests and Management of Bronchiolitis

Science.gov (United States)

Sarmiento, Lorena; Rojas-Soto, Gladys E.

2017-01-01

Background The aim of the present study was to determine predictors of inappropriate use of diagnostic tests and management of bronchiolitis in a population of hospitalized infants. Methods In an analytical cross-sectional study, we determined independent predictors of the inappropriate use of diagnostic tests and management of bronchiolitis in a population of hospitalized infants. We defined a composite outcome score as the main outcome variable. Results Of the 303 included patients, 216 (71.3%) experienced an inappropriate use of diagnostic tests and treatment of bronchiolitis. After controlling for potential confounders, it was found that atopic dermatitis (OR 5.30; CI 95% 1.14–24.79; p = 0.034), length of hospital stay (OR 1.48; CI 95% 1.08–2.03; p = 0.015), and the number of siblings (OR 1.92; CI 95% 1.13–3.26; p = 0.015) were independent predictors of an inappropriate use of diagnostic tests and treatment of the disease. Conclusions Inappropriate use of diagnostic tests and treatment of bronchiolitis was a highly prevalent outcome in our population of study. Participants with atopic dermatitis, a longer hospital stay, and a greater number of siblings were at increased risk for inappropriate use of diagnostic tests and management of the disease. PMID:28758127

Optimal Combinations of Diagnostic Tests Based on AUC.

Science.gov (United States)

Huang, Xin; Qin, Gengsheng; Fang, Yixin

2011-06-01

When several diagnostic tests are available, one can combine them to achieve better diagnostic accuracy. This article considers the optimal linear combination that maximizes the area under the receiver operating characteristic curve (AUC); the estimates of the combination's coefficients can be obtained via a nonparametric procedure. However, for estimating the AUC associated with the estimated coefficients, the apparent estimation by re-substitution is too optimistic. To adjust for the upward bias, several methods are proposed. Among them the cross-validation approach is especially advocated, and an approximated cross-validation is developed to reduce the computational cost. Furthermore, these proposed methods can be applied for variable selection to select important diagnostic tests. The proposed methods are examined through simulation studies and applications to three real examples. © 2010, The International Biometric Society.

Improving prescribing practices with rapid diagnostic tests (RDTs)

DEFF Research Database (Denmark)

Burchett, Helen E D; Leurent, Baptiste; Baiden, Frank

2017-01-01

OBJECTIVES: The overuse of antimalarial drugs is widespread. Effective methods to improve prescribing practice remain unclear. We evaluated the impact of 10 interventions that introduced rapid diagnostic tests for malaria (mRDTs) on the use of tests and adherence to results in different contexts...... packages, supervision, supplies and community sensitisation. OUTCOME MEASURES: Analysis explored variation in: (1) uptake of mRDTs (% febrile patients tested); (2) provider adherence to positive mRDTs (% Plasmodium falciparum positive prescribed/given Artemisinin Combination Treatment); (3) provider...... characteristics fitted with their own priorities. Goodness of fit of mRDTs with existing consultation and diagnostic practices appeared crucial to maximising the impact of mRDTs on care, as did prior familiarity with malaria testing; adequate human resources and supplies; possible alternative treatments for m...

Observations of immuno-gold conjugates on influenza viruses using waveguide-mode sensors.

Directory of Open Access Journals (Sweden)

Subash C B Gopinath

Full Text Available Gold nanoparticles were conjugated to an antibody (immuno-AuNP against A/Udorn/307/1972 (H3N2 influenza virus to detect viruses on a sensing plate designed for an evanescent field-coupled waveguide-mode sensor. Experiments were conducted using human influenza A/H3N2 strains, and immuno-AuNP could detect 8×10(5 PFU/ml (40 pg/µl intact A/Udorn/307/1972 and 120 pg/µl A/Brisbane/10/2007. Furthermore, increased signal magnitude was achieved in the presence of non-ionic detergent, as the virtual detection level was increased to 8×10(4 PFU/ml A/Udorn/307/1972. Immuno-AuNPs were then complexed with viruses to permit direct observation, and they formed a ring of confined nanodots on the membrane of both intact and detergent-treated viruses as directly visualized by scanning electron microscopy. With this complex the detection limit was improved further to 8×10(3 PFU/ml on anti-rabbit IgG immobilized sensing plate. These strategies introduce methods for observing trapped intact viruses on the sensing plates generated for optical systems.

Drug sensitivity testing platforms for gastric cancer diagnostics.

Science.gov (United States)

Lau, Vianne; Wong, Andrea Li-Ann; Ng, Christopher; Mok, Yingting; Lakshmanan, Manikandan; Yan, Benedict

2016-02-01

Gastric cancer diagnostics has traditionally been histomorphological and primarily the domain of surgical pathologists. Although there is an increasing usage of molecular and genomic techniques for clinical diagnostics, there is an emerging field of personalised drug sensitivity testing. In this review, we describe the various personalised drug sensitivity testing platforms and discuss the challenges facing clinical adoption of these assays for gastric cancer. 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/

Rapid Immuno-Chromatographic Assay for the Detection of Antibodies to HIV Compare with Elisa among Voluntary and Replacement Blood Donor of Mymensingh Medical College Hospital.

Science.gov (United States)

Chakrabarty, P; Rudra, S; Hossain, M A; Begum, S A; Mirza, T T; Rudra, M

2015-04-01

Suitable algorithms based on a combination of two or more simple rapid HIV assays have been shown to have a diagnostic accuracy comparable to double enzyme-linked immunosorbent assay (ELISA) or double ELISA with Western Blot strategies. The aims of this study were to evaluate the performance of five simple rapid HIV assays using whole blood samples from voluntary and replacement blood donors & HIV-infected patients (positive samples from BSMMU, Dhaka). Five rapid HIV assays: Determine™ HIV-1/2 (Inverness Medical), SD Bioline HIV 1/2 3.0 (Standard Diagnostics Inc.), First Response HIV Card 1-2.0 (PMC Medical India Pvt Ltd.), HIV1/2 Stat-Pak Dipstick (Chembio Diagnostic System, Inc) and Uni-Gold™ HIV-1/2 (Biotech) were evaluated between 1st February to 30th June, 2013 using 400 whole blood samples from voluntary and replacement blood donors. All samples that were reactive on all or any of the five rapid assays and 10% of non-reactive samples were tested on a confirmatory Inno-Lia HIV I/II immunoblot assay (Immunogenetics). Only 01 sample including ten positive samples from BSMMU were confirmed HIV-1 antibody positive, while 399 were HIV negative. The sensitivity at initial testing of Determine, SD Bioline and Uni-Gold™ was 100% (95% CI; 99.1-100) while First Response and Stat-Pak had sensitivity of 99.5% (95% CI; 98.2-99.9) and 97.7% (95% CI; 95.7-98.9) respectively, which increased to 100% (95% CI; 99.1-100) on repeat testing. The initial specificity of the Uni-Gold™ assay was 100% (95% CI; 99.6-100) while specificities were 99.6% (95% CI; 99-99.9), 99.4% (95% CI; 98.8-99.7), 99.6% (95% CI; 99-99.9) and 99.8% (95% CI; 99.3-99.9) for Determine, SD Bioline, First Response and Stat-Pak assays, respectively. There was no any sample which was concordantly false positive in Uni-Gold™, Determine and SD Bioline assays. An alternative confirmatory HIV testing strategy based on initial testing on either SD Bioline or Determine assays followed by testing of reactive

Nonparametric predictive inference for combining diagnostic tests with parametric copula

Science.gov (United States)

Muhammad, Noryanti; Coolen, F. P. A.; Coolen-Maturi, T.

2017-09-01

Measuring the accuracy of diagnostic tests is crucial in many application areas including medicine and health care. The Receiver Operating Characteristic (ROC) curve is a popular statistical tool for describing the performance of diagnostic tests. The area under the ROC curve (AUC) is often used as a measure of the overall performance of the diagnostic test. In this paper, we interest in developing strategies for combining test results in order to increase the diagnostic accuracy. We introduce nonparametric predictive inference (NPI) for combining two diagnostic test results with considering dependence structure using parametric copula. NPI is a frequentist statistical framework for inference on a future observation based on past data observations. NPI uses lower and upper probabilities to quantify uncertainty and is based on only a few modelling assumptions. While copula is a well-known statistical concept for modelling dependence of random variables. A copula is a joint distribution function whose marginals are all uniformly distributed and it can be used to model the dependence separately from the marginal distributions. In this research, we estimate the copula density using a parametric method which is maximum likelihood estimator (MLE). We investigate the performance of this proposed method via data sets from the literature and discuss results to show how our method performs for different family of copulas. Finally, we briefly outline related challenges and opportunities for future research.

ITER diagnostics: Maintenance and commissioning in the hot cell test bed

International Nuclear Information System (INIS)

Walker, C.I.; Barnsley, R.; Costley, A.E.; Gottfried, R.; Haist, B.; Itami, K.; Kondoh, T.; Loesser, G.D.; Palmer, J.; Sugie, T.; Tesini, A.; Vayakis, G.

2005-01-01

In-vessel diagnostic equipment in ITER integrated in six equatorial and 12 upper ports, 16 divertor cassettes and five lower ports is designed to be removed in modules and then repaired, tested and commissioned in the same location at the ITER hot cell. The repair requirements and tests on these components are described along with design features that facilitate repair. The testing establishes the repair strategy, qualifies the refurbishment work and finally checks the mechanical and diagnostic function before the return of the modules. At the hot cell, a dummy port is provided for tests of mechanical and vacuum integrity as well as commissioning of the diagnostic equipment. The scope of the hot cell maintenance and commissioning activities is summarised and an overview of the integration of the diagnostic equipment is given

Diagnostic reliability of MMPI-2 computer-based test interpretations.

Science.gov (United States)

Pant, Hina; McCabe, Brian J; Deskovitz, Mark A; Weed, Nathan C; Williams, John E

2014-09-01

Reflecting the common use of the MMPI-2 to provide diagnostic considerations, computer-based test interpretations (CBTIs) also typically offer diagnostic suggestions. However, these diagnostic suggestions can sometimes be shown to vary widely across different CBTI programs even for identical MMPI-2 profiles. The present study evaluated the diagnostic reliability of 6 commercially available CBTIs using a 20-item Q-sort task developed for this study. Four raters each sorted diagnostic classifications based on these 6 CBTI reports for 20 MMPI-2 profiles. Two questions were addressed. First, do users of CBTIs understand the diagnostic information contained within the reports similarly? Overall, diagnostic sorts of the CBTIs showed moderate inter-interpreter diagnostic reliability (mean r = .56), with sorts for the 1/2/3 profile showing the highest inter-interpreter diagnostic reliability (mean r = .67). Second, do different CBTIs programs vary with respect to diagnostic suggestions? It was found that diagnostic sorts of the CBTIs had a mean inter-CBTI diagnostic reliability of r = .56, indicating moderate but not strong agreement across CBTIs in terms of diagnostic suggestions. The strongest inter-CBTI diagnostic agreement was found for sorts of the 1/2/3 profile CBTIs (mean r = .71). Limitations and future directions are discussed. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Considerations on development, validation, application, and quality control of immuno(metric) biomarker assays in clinical cancer research: an EORTC-NCI working group report.

NARCIS (Netherlands)

Sweep, C.G.J.; Fritsche, H.A.; Gion, M.; Klee, G.G.; Schmitt, M.

2003-01-01

A major dilemma associated with immuno(metric) assays for biomarkers is that various kits employing antibodies with differing specificities and binding affinities may generate non-equivalent test results. Also, variation in sample processing and the use of different standards (reference material)

A diagnostic test for apraxia in stroke patients: internal consistency and diagnostic value.

NARCIS (Netherlands)

Heugten, C.M. van; Dekker, J.; Deelman, B.G.; Stehmann-Saris, F.C.; Kinebanian, A.

1999-01-01

The internal consistency and the diagnostic value of a test for apraxia in patients having had a stroke are presented. Results indicate that the items of the test form a strong and consistent scale: Cronbach's alpha as well as the results of a Mokken scale analysis present good reliability and good

Analysis of the Astronomy Diagnostic Test

Science.gov (United States)

Brogt, Erik; Sabers, Darrell; Prather, Edward E.; Deming, Grace L.; Hufnagel, Beth; Slater, Timothy F.

2007-01-01

Seventy undergraduate class sections were examined from the database of Astronomy Diagnostic Test (ADT) results of Deming and Hufnagel to determine if course format correlated with ADT normalized gain scores. Normalized gains were calculated for four different classroom scenarios: lecture, lecture with discussion, lecture with lab, and lecture…

Diagnostic development and support of MHD test facilities

Energy Technology Data Exchange (ETDEWEB)

1990-01-01

The Diagnostic Instrumentation and Analysis Laboratory (DIAL) at Mississippi State University (MSU) is developing diagnostic instruments for MHD power train data acquisition and for support of MHD component development test facilities. Microprocessor-controlled optical instruments, initially developed for Heat Recovery/Seed Recovery support, are being refined, and new systems to measure temperatures and gas-seed-slag stream characteristics are being developed. To further data acquisition and analysis capabilities, the diagnostic systems are being interfaced with DIAL's computers. Technical support for the diagnostic needs of the national MHD research effort is being provided. DIAL personnel will also cooperate with government agencies and private industries to improve the transformation of research and development results into processes, products and services applicable to their needs. 25 figs., 6 tabs.

Diagnostic development and support of MHD test facilities

International Nuclear Information System (INIS)

Shepard, W.S.; Cook, R.L.

1990-01-01

The Diagnostic Instrumentation and Analysis Laboratory (DIAL) at Mississippi State University (MSU) is developing diagnostic instruments for MHD power train data acquisition and for support of MHD component development test facilities. Microprocessor-controlled optical instruments, initially developed for Heat Recovery/ Seed Recovery support, are being refined, and new systems to measure temperatures and gas-seed-slag stream characteristics are being developed. To further data acquisition and analysis capabilities, the diagnostic systems are being interfaced with DIAL's computers. Technical support for the diagnostic needs of the national MHD research effort is being provided. DIAL personnel will also cooperate with government agencies and private industries to improve the transformation of research and development results into processes, products and services applicable to their needs

Chromatographic Monoliths for High-Throughput Immunoaffinity Isolation of Transferrin from Human Plasma

Directory of Open Access Journals (Sweden)

Irena Trbojević-Akmačić

2016-06-01

Full Text Available Changes in protein glycosylation are related to different diseases and have a potential as diagnostic and prognostic disease biomarkers. Transferrin (Tf glycosylation changes are common marker for congenital disorders of glycosylation. However, biological interindividual variability of Tf N-glycosylation and genes involved in glycosylation regulation are not known. Therefore, high-throughput Tf isolation method and large scale glycosylation studies are needed in order to address these questions. Due to their unique chromatographic properties, the use of chromatographic monoliths enables very fast analysis cycle, thus significantly increasing sample preparation throughput. Here, we are describing characterization of novel immunoaffinity-based monolithic columns in a 96-well plate format for specific high-throughput purification of human Tf from blood plasma. We optimized the isolation and glycan preparation procedure for subsequent ultra performance liquid chromatography (UPLC analysis of Tf N-glycosylation and managed to increase the sensitivity for approximately three times compared to initial experimental conditions, with very good reproducibility. This work is licensed under a Creative Commons Attribution 4.0 International License.

9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

Science.gov (United States)

2010-01-01

... samples for diagnostic tests. 147.8 Section 147.8 Animals and Animal Products ANIMAL AND PLANT HEALTH... IMPROVEMENT PLAN Blood Testing Procedures § 147.8 Procedures for preparing egg yolk samples for diagnostic... for diagnostic testing. (b) The authorized laboratory must identify each egg as to the breeding flock...

Rapid diagnostic tests for typhoid and paratyphoid (enteric) fever.

Science.gov (United States)

Wijedoru, Lalith; Mallett, Sue; Parry, Christopher M

2017-05-26

Differentiating both typhoid (Salmonella Typhi) and paratyphoid (Salmonella Paratyphi A) infection from other causes of fever in endemic areas is a diagnostic challenge. Although commercial point-of-care rapid diagnostic tests (RDTs) for enteric fever are available as alternatives to the current reference standard test of blood or bone marrow culture, or to the widely used Widal Test, their diagnostic accuracy is unclear. If accurate, they could potentially replace blood culture as the World Health Organization (WHO)-recommended main diagnostic test for enteric fever. To assess the diagnostic accuracy of commercially available rapid diagnostic tests (RDTs) and prototypes for detecting Salmonella Typhi or Paratyphi A infection in symptomatic persons living in endemic areas. We searched the Cochrane Infectious Diseases Group Specialized Register, MEDLINE, Embase, Science Citation Index, IndMED, African Index Medicus, LILACS, ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) up to 4 March 2016. We manually searched WHO reports, and papers from international conferences on Salmonella infections. We also contacted test manufacturers to identify studies. We included diagnostic accuracy studies of enteric fever RDTs in patients with fever or with symptoms suggestive of enteric fever living in endemic areas. We classified the reference standard used as either Grade 1 (result from a blood culture and a bone marrow culture) or Grade 2 (result from blood culture and blood polymerase chain reaction, or from blood culture alone). Two review authors independently extracted the test result data. We used a modified QUADAS-2 extraction form to assess methodological quality. We performed a meta-analysis when there were sufficient studies for the test and heterogeneity was reasonable. Thirty-seven studies met the inclusion criteria and included a total of 5080 participants (range 50 to 1732). Enteric fever prevalence

Antiphospholipid Syndrome Laboratory Testing and Diagnostic Strategies

Science.gov (United States)

Ortel, Thomas L.

2016-01-01

The Antiphospholipid Syndrome (APS) is diagnosed in patients with recurrent thromboembolic events and/or pregnancy loss in the presence of persistent laboratory evidence for antiphospholipid antibodies. Diagnostic tests for the detection of antiphospholipid antibodies include laboratory assays that detect anticardiolipin antibodies, lupus anticoagulants, and anti-β2-glycoprotein I antibodies. These assays have their origins beginning more than sixty years ago, with the identification of the biologic false positive test for syphilis, the observation of ‘circulating anticoagulants’ in certain patients with systemic lupus erythematosus, the identification of cardiolipin as a key component in the serologic test for syphilis, and the recognition and characterization of a ‘cofactor’ for antibody binding to phospholipids. Although these assays have been used clinically for many years, there are still problems with the accurate diagnosis of patients with this syndrome. For example, lupus anticoagulant testing can be difficult to interpret in patients receiving anticoagulant therapy, but most patients with a thromboembolic event will already be anticoagulated before the decision to perform the tests has been made. In addition to understanding limitations of the assays, clinicians also need to be aware of which patients should be tested and not obtain testing on patients unlikely to have APS. New tests and diagnostic strategies are in various stages of development and should help improve our ability to accurately diagnose this important clinical disorder. PMID:22473619

30 CFR 250.522 - When do I have to repeat casing diagnostic testing?

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false When do I have to repeat casing diagnostic... Operations Casing Pressure Management § 250.522 When do I have to repeat casing diagnostic testing? Casing diagnostic testing must be repeated according to the following table: When * * * you must repeat diagnostic...

Characterization of the immuno dominant regions within gp41 of env gene of HIV in Pakistan

International Nuclear Information System (INIS)

Nisar, L.; Qadir, M.I.; Nisa, T.; Malik, S.A.; Tabassum, N.

2011-01-01

Objective of the present study was to characterize the immuno dominant sequences of gp41 in HIV strain in Pakistani population so that vaccine may be prepared based upon these regions. A total of 25 specimens were collected from HIV patients of different areas of Pakistan. The viral RNA was isolated using QIAamp MinElute Spin Kit manufactured by Quiagen, California, USA. RT-PCR was done for amplification of the required region and confirmed by gel electrophoresis. The nucleotides of the required regions were sequenced using Big Dye terminator. Less than 20% of the specimens had mutations in immuno dominant regions, so it may be concluded that immuno dominant regions of gp41 in HIV strain in Pakistani population are conservatives and vaccine based upon these regions may prove active immunization against the disease. (author)

Characterization of the immuno dominant regions within gp41 of env gene of HIV in Pakistan

Energy Technology Data Exchange (ETDEWEB)

Nisar, L; Qadir, M I; Nisa, T; Malik, S A; Tabassum, N

2011-08-15

Objective of the present study was to characterize the immuno dominant sequences of gp41 in HIV strain in Pakistani population so that vaccine may be prepared based upon these regions. A total of 25 specimens were collected from HIV patients of different areas of Pakistan. The viral RNA was isolated using QIAamp MinElute Spin Kit manufactured by Quiagen, California, USA. RT-PCR was done for amplification of the required region and confirmed by gel electrophoresis. The nucleotides of the required regions were sequenced using Big Dye terminator. Less than 20% of the specimens had mutations in immuno dominant regions, so it may be concluded that immuno dominant regions of gp41 in HIV strain in Pakistani population are conservatives and vaccine based upon these regions may prove active immunization against the disease. (author)

More Than Just Accuracy: A Novel Method to Incorporate Multiple Test Attributes in Evaluating Diagnostic Tests Including Point of Care Tests.

Science.gov (United States)

Thompson, Matthew; Weigl, Bernhard; Fitzpatrick, Annette; Ide, Nicole

2016-01-01

Current frameworks for evaluating diagnostic tests are constrained by a focus on diagnostic accuracy, and assume that all aspects of the testing process and test attributes are discrete and equally important. Determining the balance between the benefits and harms associated with new or existing tests has been overlooked. Yet, this is critically important information for stakeholders involved in developing, testing, and implementing tests. This is particularly important for point of care tests (POCTs) where tradeoffs exist between numerous aspects of the testing process and test attributes. We developed a new model that multiple stakeholders (e.g., clinicians, patients, researchers, test developers, industry, regulators, and health care funders) can use to visualize the multiple attributes of tests, the interactions that occur between these attributes, and their impacts on health outcomes. We use multiple examples to illustrate interactions between test attributes (test availability, test experience, and test results) and outcomes, including several POCTs. The model could be used to prioritize research and development efforts, and inform regulatory submissions for new diagnostics. It could potentially provide a way to incorporate the relative weights that various subgroups or clinical settings might place on different test attributes. Our model provides a novel way that multiple stakeholders can use to visualize test attributes, their interactions, and impacts on individual and population outcomes. We anticipate that this will facilitate more informed decision making around diagnostic tests.

Molecular Diagnostic Tests for Microsporidia

Directory of Open Access Journals (Sweden)

Kaya Ghosh

2009-01-01

Full Text Available The Microsporidia are a ubiquitous group of eukaryotic obligate intracellular parasites which were recognized over 100 years ago with the description of Nosema bombycis, a parasite of silkworms. It is now appreciated that these organisms are related to the Fungi. Microsporidia infect all major animal groups most often as gastrointestinal pathogens; however they have been reported from every tissue and organ, and their spores are common in environmental sources such as ditch water. Several different genera of these organisms infect humans, but the majority of infections are due to either Enterocytozoon bieneusi or Encephalitozoon species. These pathogens can be difficult to diagnose, but significant progress has been made in the last decade in the development of molecular diagnostic reagents for these organisms. This report reviews the molecular diagnostic tests that have been described for the identification of the microsporidia that infect humans.

Chromatographic hydrogen isotope separation

International Nuclear Information System (INIS)

Aldridge, F.T.

1983-01-01

Intermetallic compounds with the CaCu5 type of crystal structure, particularly LaNiCo and CaNi5, exhibit high separation factors and fast equilibrium times and therefore are useful for packing a chromatographic hydrogen isotope separation column. The addition of an inert metal to dilute the hydride improves performance of the column. A large scale multi-stage chromatographic separation process run as a secondary process off a hydrogen feedstream from an industrial plant which uses large volumes of hydrogen can produce large quantities of heavy water at an effective cost for use in heavy water reactors

Chromatographic hydrogen isotope separation

International Nuclear Information System (INIS)

Aldridge, F.T.

1981-01-01

Intermetallic compounds with the CaCu5 type of crystal structure , particularly LaNiCo and CaNi5, exhibit high separation factors and fast equilibrium times and therefore are useful for packing a chromatographic hydrogen isotope separation colum. The addition of an inert metal to dilute the hydride improves performance of the column. A large scale mutli-stage chromatographic separation process run as a secondary process off a hydrogen feedstream from an industrial plant which uses large volumes of hydrogen can produce large quantities of heavy water at an effective cost for use in heavy water reactors

Network meta-analysis of diagnostic test accuracy studies identifies and ranks the optimal diagnostic tests and thresholds for health care policy and decision-making.

Science.gov (United States)

Owen, Rhiannon K; Cooper, Nicola J; Quinn, Terence J; Lees, Rosalind; Sutton, Alex J

2018-07-01

Network meta-analyses (NMA) have extensively been used to compare the effectiveness of multiple interventions for health care policy and decision-making. However, methods for evaluating the performance of multiple diagnostic tests are less established. In a decision-making context, we are often interested in comparing and ranking the performance of multiple diagnostic tests, at varying levels of test thresholds, in one simultaneous analysis. Motivated by an example of cognitive impairment diagnosis following stroke, we synthesized data from 13 studies assessing the efficiency of two diagnostic tests: Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA), at two test thresholds: MMSE accounting for the correlations between multiple test accuracy measures from the same study. We developed and successfully fitted a model comparing multiple tests/threshold combinations while imposing threshold constraints. Using this model, we found that MoCA at threshold decision making. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Efficient strategies to find diagnostic test accuracy studies in kidney journals.

Science.gov (United States)

Rogerson, Thomas E; Ladhani, Maleeka; Mitchell, Ruth; Craig, Jonathan C; Webster, Angela C

2015-08-01

Nephrologists looking for quick answers to diagnostic clinical questions in MEDLINE can use a range of published search strategies or Clinical Query limits to improve the precision of their searches. We aimed to evaluate existing search strategies for finding diagnostic test accuracy studies in nephrology journals. We assessed the accuracy of 14 search strategies for retrieving diagnostic test accuracy studies from three nephrology journals indexed in MEDLINE. Two investigators hand searched the same journals to create a reference set of diagnostic test accuracy studies to compare search strategy results against. We identified 103 diagnostic test accuracy studies, accounting for 2.1% of all studies published. The most specific search strategy was the Narrow Clinical Queries limit (sensitivity: 0.20, 95% CI 0.13-0.29; specificity: 0.99, 95% CI 0.99-0.99). Using the Narrow Clinical Queries limit, a searcher would need to screen three (95% CI 2-6) articles to find one diagnostic study. The most sensitive search strategy was van der Weijden 1999 Extended (sensitivity: 0.95; 95% CI 0.89-0.98; specificity 0.55, 95% CI 0.53-0.56) but required a searcher to screen 24 (95% CI 23-26) articles to find one diagnostic study. Bachmann 2002 was the best balanced search strategy, which was sensitive (0.88, 95% CI 0.81-0.94), but also specific (0.74, 95% CI 0.73-0.75), with a number needed to screen of 15 (95% CI 14-17). Diagnostic studies are infrequently published in nephrology journals. The addition of a strategy for diagnostic studies to a subject search strategy in MEDLINE may reduce the records needed to screen while preserving adequate search sensitivity for routine clinical use. © 2015 Asian Pacific Society of Nephrology.

Characterization of the Goubau line for testing beam diagnostic instruments

Science.gov (United States)

Kim, S. Y.; Stulle, F.; Sung, C. K.; Yoo, K. H.; Seok, J.; Moon, K. J.; Choi, C. U.; Chung, Y.; Kim, G.; Woo, H. J.; Kwon, J.; Lee, I. G.; Choi, E. M.; Chung, M.

2017-12-01

One of the main characteristics of the Goubau line is that it supports a low-loss, non-radiated surface wave guided by a dielectric-coated metal wire. The dominant mode of the surface wave along the Goubau line is a TM01 mode, which resembles the pattern of the electromagnetic fields induced in the metallic beam pipe when the charged particle beam passes through it. Therefore, the Goubau line can be used for the preliminary bench test and performance optimization of the beam diagnostic instruments without requiring charged particle beams from the accelerators. In this paper, we discuss the basic properties of the Goubau line for testing beam diagnostic instruments and present the initial test results for button-type beam position monitors (BPMs). The experimental results are consistent with the theoretical estimations, which indicates that Goubau line allows effective testing of beam diagnostic equipment.

Optimization of the gas chromatographic separations

International Nuclear Information System (INIS)

Gasco Sanchez, L.

1973-01-01

A review and a critical study on the optimization of the gas chromatographic separations are made. After dealing with the fundamental gas chromatographic equations, some methods of expressing column performances are discussed: performance indices, performance parameters, resolution and effective plate number per unit time. This is completed with a comparative study on performances of various types of columns. Moreover, optimization methods for operating chromatographic conditions are extensively dealt with: as resolution optimization, separation time, and normalization techniques for the time of analysis in order to achieve the maximum resolution at constant time. Finally, some others non operating parameters such as: selectivity of stationary phases, column preparation and optimization methods by means of computers are studied. (Author) 68 refs

Better Tests, Better Care: Improved Diagnostics for Infectious Diseases

Science.gov (United States)

Caliendo, Angela M.; Gilbert, David N.; Ginocchio, Christine C.; Hanson, Kimberly E.; May, Larissa; Quinn, Thomas C.; Tenover, Fred C.; Alland, David; Blaschke, Anne J.; Bonomo, Robert A.; Carroll, Karen C.; Ferraro, Mary Jane; Hirschhorn, Lisa R.; Joseph, W. Patrick; Karchmer, Tobi; MacIntyre, Ann T.; Reller, L. Barth; Jackson, Audrey F.

2013-01-01

In this IDSA policy paper, we review the current diagnostic landscape, including unmet needs and emerging technologies, and assess the challenges to the development and clinical integration of improved tests. To fulfill the promise of emerging diagnostics, IDSA presents recommendations that address a host of identified barriers. Achieving these goals will require the engagement and coordination of a number of stakeholders, including Congress, funding and regulatory bodies, public health agencies, the diagnostics industry, healthcare systems, professional societies, and individual clinicians. PMID:24200831

A Small-Scale Low-Cost Gas Chromatograph

Science.gov (United States)

Gros, Natasa; Vrtacnik, Margareta

2005-01-01

The design and application of a small-scale portable gas chromatograph for learning of the basic concepts of chromatography is described. The apparatus consists of two basic separable units, which includes a chromatographic unit and an electronic unit.

Mixed Portmanteau Test for Diagnostic Checking of Time Series Models

Directory of Open Access Journals (Sweden)

Sohail Chand

2014-01-01

Full Text Available Model criticism is an important stage of model building and thus goodness of fit tests provides a set of tools for diagnostic checking of the fitted model. Several tests are suggested in literature for diagnostic checking. These tests use autocorrelation or partial autocorrelation in the residuals to criticize the adequacy of fitted model. The main idea underlying these portmanteau tests is to identify if there is any dependence structure which is yet unexplained by the fitted model. In this paper, we suggest mixed portmanteau tests based on autocorrelation and partial autocorrelation functions of the residuals. We derived the asymptotic distribution of the mixture test and studied its size and power using Monte Carlo simulations.

Immuno-flow cytometric detection of the ichthyotoxic dinoflagellates Gyrodinium aureolum and Gymnodinium nagasakiense: independence of physiological state

Science.gov (United States)

Vrieling, Engel G.; van de Poll, Willem H.; Vriezekolk, Gertie; Gieskes, Winfried W. C.

1997-05-01

The ichthyotoxic dinoflagellates Gyrodinium aureolum and Gymnodinium nagasakiense were cultured under different environmental conditions to test possible variability in immunochemical labelling intensity of cell-surface antigens using species-specific monoclonal antibodies. Variation of antigen abundance (which is directly related to labelling intensity) at the cell surface, determined by immuno-flow cytometry of cells labelled with FITC, appeared to be small but significant compared to control cultures. In general, a minor decrease in FIX fluorescence was recorded during exponential growth, followed by an increase during stationary growth. FITC fluorescence was correlated with cell size, shape and structure. This suggests a constant number of antigens per unit of cell surface. In all cultures, immunochemically labelled cells were distinguished clearly from unlabelled cells; immuno-flow cytometric identification is apparently not affected by growth conditions. Only at the end of the stationary growth phase in batch cultures did the FITC fluorescence values drop, which suggests that unhealthy, dying or lysing cells may either alter the composition of the cell surface or just fail to express the antigen.

Development of diagnostic test instruments to reveal level student conception in kinematic and dynamics

Science.gov (United States)

Handhika, J.; Cari, C.; Suparmi, A.; Sunarno, W.; Purwandari, P.

2018-03-01

The purpose of this research was to develop a diagnostic test instrument to reveal students' conceptions in kinematics and dynamics. The diagnostic test was developed based on the content indicator the concept of (1) displacement and distance, (2) instantaneous and average velocity, (3) zero and constant acceleration, (4) gravitational acceleration (5) Newton's first Law, (6) and Newton's third Law. The diagnostic test development model includes: Diagnostic test requirement analysis, formulating test-making objectives, developing tests, checking the validity of the content and the performance of reliability, and application of tests. The Content Validation Index (CVI) results in the category are highly relevant, with a value of 0.85. Three questions get negative Content Validation Ratio CVR) (-0.6), after revised distractors and clarify visual presentation; the CVR become 1 (highly relevant). This test was applied, obtained 16 valid test items, with Cronbach Alpha value of 0.80. It can conclude that diagnostic test can be used to reveal the level of students conception in kinematics and dynamics.

Comparison of premier CAMPY enzyme immunoassay (EIA), ProSpecT Campylobacter EIA, and ImmunoCard STAT! CAMPY tests with culture for laboratory diagnosis of Campylobacter enteric infections.

Science.gov (United States)

Granato, Paul A; Chen, Li; Holiday, Iris; Rawling, Russell A; Novak-Weekley, Susan M; Quinlan, Tammy; Musser, Kimberlee A

2010-11-01

Campylobacter enteritis is a food-borne or waterborne illness caused almost exclusively by Campylobacter jejuni and, to a lesser extent, by Campylobacter coli. These organisms produce indistinguishable clinical diseases and together represent the second most common cause of bacterial diarrhea in the United States and the leading cause of enteric infection throughout the world. The conventional approach to the laboratory diagnosis of Campylobacter enteritis is based on the recovery of the organism from a stool specimen, which requires the use of a specialized medium incubated at 42°C for several days in an artificially created microaerophilic environment. Recently, several commercially available enzyme immunoassays (EIAs) have been developed for the direct detection of C. jejuni and C. coli in stool specimens. This study compared conventional culture with three EIA methods, the Premier CAMPY EIA (Meridian Bioscience, Cincinnati, OH), the ProSpecT Campylobacter EIA (Remel, Lenexa, KS), and the ImmunoCard STAT! CAMPY test (Meridian Bioscience, Cincinnati, OH), for the detection of C. jejuni and C. coli in 485 patient stool samples. Discordant results were arbitrated by using an in-house, real-time PCR assay that was developed and validated by a public health reference laboratory. Following analyses of the discrepant specimens by PCR, the sensitivity and specificity of both the Premier CAMPY and ProSpecT Campylobacter EIAs were 99.3% and 98%, respectively, while the ImmunoCard STAT! CAMPY test had a sensitivity of 98.5% and a specificity of 98.2%. By use of the PCR test as the reference standard, culture detected 127 of 135 Campylobacter-positive stool specimens, yielding a sensitivity of 94.1%. These results showed that the three EIAs evaluated in this study provide a rapid and reliable alternative for the laboratory diagnosis of enteric infections with C. jejuni and C. coli and that conventional culture may no longer be recognized as the "gold standard" for

Rapid diagnostic tests for typhoid and paratyphoid (enteric) fever

Science.gov (United States)

Wijedoru, Lalith; Mallett, Sue; Parry, Christopher M

2017-01-01

Background Differentiating both typhoid (Salmonella Typhi) and paratyphoid (Salmonella Paratyphi A) infection from other causes of fever in endemic areas is a diagnostic challenge. Although commercial point-of-care rapid diagnostic tests (RDTs) for enteric fever are available as alternatives to the current reference standard test of blood or bone marrow culture, or to the widely used Widal Test, their diagnostic accuracy is unclear. If accurate, they could potentially replace blood culture as the World Health Organization (WHO)-recommended main diagnostic test for enteric fever. Objectives To assess the diagnostic accuracy of commercially available rapid diagnostic tests (RDTs) and prototypes for detecting Salmonella Typhi or Paratyphi A infection in symptomatic persons living in endemic areas. Search methods We searched the Cochrane Infectious Diseases Group Specialized Register, MEDLINE, Embase, Science Citation Index, IndMED, African Index Medicus, LILACS, ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) up to 4 March 2016. We manually searched WHO reports, and papers from international conferences on Salmonella infections. We also contacted test manufacturers to identify studies. Selection criteria We included diagnostic accuracy studies of enteric fever RDTs in patients with fever or with symptoms suggestive of enteric fever living in endemic areas. We classified the reference standard used as either Grade 1 (result from a blood culture and a bone marrow culture) or Grade 2 (result from blood culture and blood polymerase chain reaction, or from blood culture alone). Data collection and analysis Two review authors independently extracted the test result data. We used a modified QUADAS-2 extraction form to assess methodological quality. We performed a meta-analysis when there were sufficient studies for the test and heterogeneity was reasonable. Main results Thirty-seven studies met the inclusion

Rapid and sensitive detection of cytokines using functionalized gold nanoparticle-based immuno-PCR, comparison with immuno-PCR and ELISA

Czech Academy of Sciences Publication Activity Database

Potůčková, Lucie; Franko, Filip; Bambousková, Monika; Dráber, Petr

2011-01-01

Roč. 371, 1-2 (2011), s. 38-47 ISSN 0022-1759 R&D Projects: GA AV ČR KAN200520701; GA MŠk 1M0506; GA MŠk LC545; GA ČR GA301/09/1826; GA ČR GAP302/10/1759; GA ČR(CZ) GD204/05/H023 Grant - others:AV ČR(CZ) M200520901 Institutional research plan: CEZ:AV0Z50520514 Keywords : immuno-PCR * nano-iPCR * nanogold particles Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.203, year: 2011

Diagnostic value of serologic tests in celiac screening

Directory of Open Access Journals (Sweden)

Hosein Saneian

2012-01-01

Conclusions: According to our study results, there is no correlation between gastrointestinal symptoms such as vomiting diarrhea, anorexia, bulimia, and failure to thrive (FFT with celiac. TTG was the best screening test method to diagnose celiac disease and other tests such as AGA and EMA do not have high diagnostic value.

Compare diagnostic tests using transformation-invariant smoothed ROC curves⋆

Science.gov (United States)

Tang, Liansheng; Du, Pang; Wu, Chengqing

2012-01-01

Receiver operating characteristic (ROC) curve, plotting true positive rates against false positive rates as threshold varies, is an important tool for evaluating biomarkers in diagnostic medicine studies. By definition, ROC curve is monotone increasing from 0 to 1 and is invariant to any monotone transformation of test results. And it is often a curve with certain level of smoothness when test results from the diseased and non-diseased subjects follow continuous distributions. Most existing ROC curve estimation methods do not guarantee all of these properties. One of the exceptions is Du and Tang (2009) which applies certain monotone spline regression procedure to empirical ROC estimates. However, their method does not consider the inherent correlations between empirical ROC estimates. This makes the derivation of the asymptotic properties very difficult. In this paper we propose a penalized weighted least square estimation method, which incorporates the covariance between empirical ROC estimates as a weight matrix. The resulting estimator satisfies all the aforementioned properties, and we show that it is also consistent. Then a resampling approach is used to extend our method for comparisons of two or more diagnostic tests. Our simulations show a significantly improved performance over the existing method, especially for steep ROC curves. We then apply the proposed method to a cancer diagnostic study that compares several newly developed diagnostic biomarkers to a traditional one. PMID:22639484

The diagnostic odds ratio: a single indicator of test performance

NARCIS (Netherlands)

Glas, Afina S.; Lijmer, Jeroen G.; Prins, Martin H.; Bonsel, Gouke J.; Bossuyt, Patrick M. M.

2003-01-01

Diagnostic testing can be used to discriminate subjects with a target disorder from subjects without it. Several indicators of diagnostic performance have been proposed, such as sensitivity and specificity. Using paired indicators can be a disadvantage in comparing the performance of competing

Diagnostic accuracy of temporomandibular disorder pain tests: a multicenter study

NARCIS (Netherlands)

Visscher, C.M.; Naeije, M.; de Laat, A.; Michelotti, A.; Nilner, M.; Craane, B.; Ekberg, E.; Farella, M.; Lobbezoo, F.

2009-01-01

AIMS: To estimate the diagnostic accuracy of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) clinical examination and of the dynamic/static tests for the recognition of TMD pain. Since the diagnosis of TMD pain is especially complicated in persistent orofacial pain

Optimal Sequential Diagnostic Strategy Generation Considering Test Placement Cost for Multimode Systems

Directory of Open Access Journals (Sweden)

Shigang Zhang

2015-10-01

Full Text Available Sequential fault diagnosis is an approach that realizes fault isolation by executing the optimal test step by step. The strategy used, i.e., the sequential diagnostic strategy, has great influence on diagnostic accuracy and cost. Optimal sequential diagnostic strategy generation is an important step in the process of diagnosis system construction, which has been studied extensively in the literature. However, previous algorithms either are designed for single mode systems or do not consider test placement cost. They are not suitable to solve the sequential diagnostic strategy generation problem considering test placement cost for multimode systems. Therefore, this problem is studied in this paper. A formulation is presented. Two algorithms are proposed, one of which is realized by system transformation and the other is newly designed. Extensive simulations are carried out to test the effectiveness of the algorithms. A real-world system is also presented. All the results show that both of them have the ability to solve the diagnostic strategy generation problem, and they have different characteristics.

Optimal Sequential Diagnostic Strategy Generation Considering Test Placement Cost for Multimode Systems

Science.gov (United States)

Zhang, Shigang; Song, Lijun; Zhang, Wei; Hu, Zheng; Yang, Yongmin

2015-01-01

Sequential fault diagnosis is an approach that realizes fault isolation by executing the optimal test step by step. The strategy used, i.e., the sequential diagnostic strategy, has great influence on diagnostic accuracy and cost. Optimal sequential diagnostic strategy generation is an important step in the process of diagnosis system construction, which has been studied extensively in the literature. However, previous algorithms either are designed for single mode systems or do not consider test placement cost. They are not suitable to solve the sequential diagnostic strategy generation problem considering test placement cost for multimode systems. Therefore, this problem is studied in this paper. A formulation is presented. Two algorithms are proposed, one of which is realized by system transformation and the other is newly designed. Extensive simulations are carried out to test the effectiveness of the algorithms. A real-world system is also presented. All the results show that both of them have the ability to solve the diagnostic strategy generation problem, and they have different characteristics. PMID:26457709

Real-Time Remote Diagnostic Monitoring Test-bed in JET

Energy Technology Data Exchange (ETDEWEB)

Castro, R. [Asociation Euratom/CIEMAT para Fusion, Madrid (Spain); Kneupner, K.; Purahoo, K. [EURATOM/UKAEA Fusion Association, Abingdon (United Kingdom); Vega, J.; Pereira, A.; Portas, A. [Association EuratomCIEMAT para Fusion, Madrid (Spain); De Arcas, G.; Lopez, J.M. [Universidad Politecnica de Madrid (Spain); Murari, A. [Consorzio RFX, Padova (Italy); Fonseca, A. [Associacao URATOM/IST, Lisboa (Portugal); Contributors, J.E. [JET-EFDA, Abingdon (United Kingdom)

2009-07-01

Based on the remote experimentation concept oriented to long pulse shots, a test-bed system has been implemented in JET. It integrates 2 functionalities. The first one is the real-time monitoring, on remote, of a reflectometer diagnostic, to visualize different data outputs and status information. The second one is the integration of dotJET (Diagnostic Overview Tool for JET), which internally provides at JET an overview about the current diagnostic systems state, in order to monitor, on remote, JET diagnostics status. The architecture of the system is formed by: the data generator components, the data distribution system, an access control service, and the client applications. In the test-bed there are two data generators: the acquisition equipment associated with the reflectometer diagnostic that generates data and status information, and dotJET server that centralize the access to the status information of JET diagnostics. The data distribution system has been implemented using a publishing-subscribing technology that receives data from data generators and redistributes them to client applications. And finally, for monitoring, a client application based on Java Web Start technology, and a dotJET client application have been used. There are 3 interesting results from this project. The first one is the analysis of different aspects (data formats, data frame rate, data resolution, etc) related with remote real-time diagnostic monitoring oriented to long pulse experiments. The second one is the definition and implementation of a flexible enough architecture, to be applied to different types of data generated from other diagnostics, and that fits with remote access requirements; and the third one is to have achieved a secure system, taking into account internal networks and firewalls aspects in JET, and securing the access from remote users. For this last issue, PAPI technology has been used, enabling access control based on user attributes, enabling mobile users to

POTENTIALITIES OF DIAGNOSTICS AND DIFFERENTIAL DIAGNOSTICS OF STOMACH DISEASES BY MEANS OF USAGE OF HIGH-PERFORMANCE BLOOD SERUM LIQUID CHROMATOGRAPHY

Directory of Open Access Journals (Sweden)

O.P. Alexeeva

2008-12-01

Full Text Available 62 patients with the endoscopically and morphologicallyverified diagnosis of the chronic gastritis, 89 patients with the morphologically verified diagnosis of stomach cancer and 43 healthy persons ages 23 to 54 years have been examined. Potentialities of the usage of high-performance blood serum liquid chromatography have been studied for the purpose of diagnostics and differential diagnostics of chronic gastritis and stomach cancer. Blood serum driedextract was investigated by means of"Milichrome A02"chromatograph (Novosibirsk, "Econova" joint-stock company. The chromatograms were treated by the multivahate cluster analysis with the formation of pathologic three-dimensional characteristic state notably differed from the healthy human image. Diagnostic sensitivity of chronic gastritis and stomach cancer acounts for accordingly 92% and 96%. Diagnostic accuracy of the method comes to 94%.

Relationship Between Preoperative Sarcopenia Status and Immuno-nutritional Parameters in Patients with Early-stage Non-small Cell Lung Cancer.

Science.gov (United States)

Shoji, Fumihiro; Matsubara, Taichi; Kozuma, Yuka; Haratake, Naoki; Akamine, Takaki; Takamori, Shinkichi; Katsura, Masakazu; Toyokawa, Gouji; Okamoto, Tatsuro; Maehara, Yoshihiko

2017-12-01

Although the skeletal muscle in the region of the third lumbar vertebra (L3) is generally assessed in order to judge sarcopenia, not every patient with non-small cell lung cancer (NSCLC) undergoes computed tomography including the L3 region. We hypothesized that immuno-nutritional parameters could predict the existence of sarcopenia in patients with NSCLC. The aim of this study was to retrospectively investigate the correlation between preoperative sarcopenia and immuno-nutritional parameters in patients with early-stage NSCLC. We selected 147 of patients with pathological stage I NSCLC who underwent preoperative measurement of immuno-nutritional parameters and CT including the L3 region. Preoperative sarcopenia was significantly associated with female gender (p=0.0003) and poor prognosis (p=0.0322). In Kaplan-Meier analysis of overall survival (OS) by preoperative sarcopenia status, the sarcopenic group had significantly shorter OS than the non-sarcopenic group (5-year OS: 87.27% vs. 77.37%, p=0.0131, log-rank test). In multivariate analysis, the preoperative sarcopenia status (hazard ratio=5.138; 95% confidence interval=2.305-11.676; psarcopenia status was significantly related to controlling nutritional status score (p=0.0071) and Geriatric Nutritional Risk Index (GNRI) (psarcopenia status and GNRI (r=0.348, psarcopenia which was associated with poor outcome in patients with early-stage NSCLC. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Determination of hexachlorocyclohexane pesticide residues in wool fat by a combined high-performance liquid chromatographic-gas-liquid chromatographic method

International Nuclear Information System (INIS)

Ali, S.L.

1978-01-01

Beta- and gamma-hexachlorocyclohexane residues were determined in twelve wool fat samples by using a combined high-performance liquid chromatographic (HPLC)-gas-liquid chromatographic (GLC) method. After extraction and chromatographic clean-up on a silca-gel column, the sample was further purified by HPLC on a reversed-phase C-18 column with methanol as the mobile phase. The final determination was effected by GLC with a 1-mCi nickel-63 electron-capture detector. The analytical method was checked by addition of carbon-14-labelled lindane and measurement of the radioactivity in a liquid scintillation counter. (Auth.)

Diagnostic precision of component-resolved vs. extract-based in vitro diagnosis of hymenoptera venom allergy: effects on clinical management.

Science.gov (United States)

Seyfarth, Florian; Miguel, Diana; Schliemann, Sibylle; Hipler, Uta-Christina

2017-05-01

The measurement of specific IgE (sIgE) antibodies plays a key role in the diagnosis of honeybee and wasp venom allergy. In recent years, component-resolved diagnosis (CRD) has been introduced, which allows for the measurement of sIgE antibodies against Api m 1, Ves v 1, Ves v 5, and Pol d 5, as well as cross-reactive carbohydrate determinants (CCDs). These tests are intended to help determine the clinical relevance of any given sensitization, especially in patients with dual sensitization. Specific IgE antibody levels were measured in 143 patients with bee and/or wasp venom allergy using the extract-based ImmunoCAP ® allergens i1 and i3 as well as the ImmunoCAP ® allergen components i208-211 and O214 (Api m 1, Ves v 1, Ves v 5, Pol d 5, CCDs). In patients with dual sensitization, inhibition testing was also performed. In a subgroup of the study population, sIgE to Api m 1, Api m 4, Pol d 5, and Ves v 5 were determined using the ISAC ® allergy microarray (n = 44). The sensitivity of Ves v 5 in patients with isolated wasp venom allergy was 78.5 %; in combination with Ves v 1, that figure increased to 92.3 %. The sensitivity of Api m 1 in individuals with isolated bee venom allergy was 25 %. CRD and inhibition testing in individuals with dual sensitization showed divergent results. CRD using the ISAC ® allergy microarray showed marked differences, especially with regard to Api m 1 and CCDs. Component-resolved tests are a valuable addition to the diagnostic spectrum as long as they are used in combination with established procedures. Apart from Ves v 5, measuring IgE antibodies to Ves v 1 should always be included in the diagnostic workup. © 2017 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Probabilistic peak detection for first-order chromatographic data.

Science.gov (United States)

Lopatka, M; Vivó-Truyols, G; Sjerps, M J

2014-03-19

We present a novel algorithm for probabilistic peak detection in first-order chromatographic data. Unlike conventional methods that deliver a binary answer pertaining to the expected presence or absence of a chromatographic peak, our method calculates the probability of a point being affected by such a peak. The algorithm makes use of chromatographic information (i.e. the expected width of a single peak and the standard deviation of baseline noise). As prior information of the existence of a peak in a chromatographic run, we make use of the statistical overlap theory. We formulate an exhaustive set of mutually exclusive hypotheses concerning presence or absence of different peak configurations. These models are evaluated by fitting a segment of chromatographic data by least-squares. The evaluation of these competing hypotheses can be performed as a Bayesian inferential task. We outline the potential advantages of adopting this approach for peak detection and provide several examples of both improved performance and increased flexibility afforded by our approach. Copyright © 2014 Elsevier B.V. All rights reserved.

Background review for diagnostic test development for Zika virus infection.

Science.gov (United States)

Charrel, Rémi N; Leparc-Goffart, Isabelle; Pas, Suzan; de Lamballerie, Xavier; Koopmans, Marion; Reusken, Chantal

2016-08-01

To review the state of knowledge about diagnostic testing for Zika virus infection and identify areas of research needed to address the current gaps in knowledge. We made a non-systematic review of the published literature about Zika virus and supplemented this with information from commercial diagnostic test kits and personal communications with researchers in European preparedness networks. The review covered current knowledge about the geographical spread, pathogen characteristics, life cycle and infection kinetics of the virus. The available molecular and serological tests and biosafety issues are described and discussed in the context of the current outbreak strain. We identified the following areas of research to address current knowledge gaps: (i) an urgent assessment of the laboratory capacity and capability of countries to detect Zika virus; (ii) rapid and extensive field validation of the available molecular and serological tests in areas with and without Zika virus transmission, with a focus on pregnant women; (iii) monitoring the genomic diversity of circulating Zika virus strains; (iv) prospective studies into the virus infection kinetics, focusing on diagnostic sampling (specimen types, combinations and timings); and (v) developing external quality assessments for molecular and serological testing, including differential diagnosis for similar viruses and symptom clusters. The availability of reagents for diagnostic development (virus strains and antigens, quantified viral ribonucleic acid) needs to be facilitated. An international laboratory response is needed, including preparation of protocols for prospective studies to address the most pressing information needs.

Can Emergency Medicine Residents Predict Cost of Diagnostic Testing?

Directory of Open Access Journals (Sweden)

Tainter, Christopher R

2017-01-01

Full Text Available Diagnostic testing represents a significant portion of healthcare spending, and cost should be considered when ordering such tests. Needless and excessive spending may occur without an appreciation of the impact on the larger healthcare system. Knowledge regarding the cost of diagnostic testing among emergency medicine (EM residents has not previously been studied. A survey was administered to 20 EM residents from a single ACGME-accredited three-year EM residency program, asking for an estimation of patient charges for 20 commonly ordered laboratory tests and seven radiological exams. We compared responses between residency classes to evaluate whether there was a difference based on level of training. The survey completion rate was 100% (20/20 residents. We noted significant discrepancies between the median resident estimates and actual charge to patient for both laboratory and radiological exams. Nearly all responses were an underestimate of the actual cost. The group median underestimation for laboratory testing was $114, for radiographs $57, and for computed tomography exams was $1,058. There was improvement in accuracy with increasing level of training. This pilot study demonstrates that EM residents have a poor understanding of the charges burdening patients and health insurance providers. In order to make balanced decisions with regard to diagnostic testing, providers must appreciate these factors. Education regarding the cost of providing emergency care is a potential area for improvement of EM residency curricula, and warrants further attention and investigation.

Laboratory development and testing of spacecraft diagnostics

Science.gov (United States)

Amatucci, William; Tejero, Erik; Blackwell, Dave; Walker, Dave; Gatling, George; Enloe, Lon; Gillman, Eric

2017-10-01

The Naval Research Laboratory's Space Chamber experiment is a large-scale laboratory device dedicated to the creation of large-volume plasmas with parameters scaled to realistic space plasmas. Such devices make valuable contributions to the investigation of space plasma phenomena under controlled, reproducible conditions, allowing for the validation of theoretical models being applied to space data. However, in addition to investigations such as plasma wave and instability studies, such devices can also make valuable contributions to the development and testing of space plasma diagnostics. One example is the plasma impedance probe developed at NRL. Originally developed as a laboratory diagnostic, the sensor has now been flown on a sounding rocket, is included on a CubeSat experiment, and will be included on the DoD Space Test Program's STP-H6 experiment on the International Space Station. In this talk, we will describe how the laboratory simulation of space plasmas made this development path possible. Work sponsored by the US Naval Research Laboratory Base Program.

30 CFR 250.523 - How long do I keep records of casing pressure and diagnostic tests?

Science.gov (United States)

2010-07-01

... and diagnostic tests? 250.523 Section 250.523 Mineral Resources MINERALS MANAGEMENT SERVICE... casing pressure and diagnostic tests? Records of casing pressure and diagnostic tests must be kept at the field office nearest the well for a minimum of 2 years. The last casing diagnostic test for each casing...

Correlations between chromatographic parameters and bioactivity predictors of potential herbicides.

Science.gov (United States)

Janicka, Małgorzata

2014-08-01

Different liquid chromatography techniques, including reversed-phase liquid chromatography on Purosphere RP-18e, IAM.PC.DD2 and Cosmosil Cholester columns and micellar liqud chromatography with a Purosphere RP-8e column and using buffered sodium dodecyl sulfate-acetonitrile as the mobile phase, were applied to study the lipophilic properties of 15 newly synthesized phenoxyacetic and carbamic acid derivatives, which are potential herbicides. Chromatographic lipophilicity descriptors were used to extrapolate log k parameters (log kw and log km) and log k values. Partitioning lipophilicity descriptors, i.e., log P coefficients in an n-octanol-water system, were computed from the molecular structures of the tested compounds. Bioactivity descriptors, including partition coefficients in a water-plant cuticle system and water-human serum albumin and coefficients for human skin partition and permeation were calculated in silico by ACD/ADME software using the linear solvation energy relationship of Abraham. Principal component analysis was applied to describe similarities between various chromatographic and partitioning lipophilicities. Highly significant, predictive linear relationships were found between chromatographic parameters and bioactivity descriptors. © The Author [2013]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Improved Chromatographic Bioavailability Estimations

National Research Council Canada - National Science Library

Dorsey, John

1996-01-01

.... Since the inception of reversed phase liquid chromatography there have been many attempts to correlate chromatographic retention with bioavailability and the most often used bulk measure, the octanol...

Immuno-cytology character recognition system - Application: Automatic determination of red blood cell groups and tissue types

International Nuclear Information System (INIS)

Passouris, Dimitris

1980-01-01

The study presented here has lead to the implementation of real time image analysis system. The image data analysis system consists of a motorised microscope, a C.C.D. array sensor, a reprocessing hardware, a processing and management microprocessor and a printer. The various immuno-haematology tests are carried out according to micro-methods, into the wells of a 'Terasaki' plate. The rate of reaction is qualitatively and quantitatively estimated. The originality of the described system is: the adaptation of the micromethod to all biological tests carried by the system; the fast reading of the biological tests (ABO-Rhesus grouping per patient in 12 seconds); the determination and implementation of a wired algorithm for the correction of the C.C.D. array sensor non-linearities. (author) [fr

Effects of chromatographic fractions of Euphorbia hirta on the rat ...

African Journals Online (AJOL)

The effects of the chromatographic fractions of Euphorbia hirta Linn on the serum biochemical parameters in rats were investigated. The ethanolic extract of this plant was subjected to chromatographic separation using the vacuum liquid chromatographic technique, a modified form of classical column chromatography.

Aquifer test interpretation using derivative analysis and diagnostic plots

Science.gov (United States)

Hernández-Espriú, Antonio; Real-Rangel, Roberto; Cortés-Salazar, Iván; Castro-Herrera, Israel; Luna-Izazaga, Gabriela; Sánchez-León, Emilio

2017-04-01

Pumping tests remain a method of choice to deduce fundamental aquifer properties and to assess well condition. In the oil and gas (O&G) industry, well testing has been the core technique in examining reservoir behavior over the last 50 years. The pressure derivative by Bourdet, it is perhaps, the most significant single development in the history of well test analysis. Recently, the so-called diagnostics plots (e.g. drawdown and drawdown derivative in a log-log plot) have been successfully tested in aquifers. However, this procedure is still underutilized by groundwater professionals. This research illustrates the applicability range, advantages and drawbacks (e.g. smoothing procedures) of diagnostic plots using field examples from a wide spectrum of tests (short/long tests, constant/variable flow rates, drawdown/buildup stages, pumping well/observation well) in dissimilar geological conditions. We analyze new and pre-existent aquifer tests in Mexico, USA, Canada, Germany, France and Saudi Arabia. In constant flow rate tests, our results show that derivative analysis is an easy, robust and powerful tool to assess near-borehole damage effects, formation heterogeneity, boundaries, flow regimes, infinite-acting radial stages, i.e., valid Theisian framework, and fracture-driven flow. In step tests, the effectiveness relies on high-frequency drawdown measurements. Moreover, we adapt O&G analytical solutions to cater for the conditions in groundwater systems. In this context, further parameters can be computed analytically from the plots, such as skin factor, head losses, wellbore storage, distance to the boundary, channel-aquifer and/or fracture zone width, among others. Therefore, diagnostic plots should be considered a mandatory tool for pumping tests analysis among hydrogeologists. This project has been supported by DGAPA (UNAM) under the research project PAPIIT IN-112815.

Rapid immuno-analytical system physically integrated with lens-free CMOS image sensor for food-borne pathogens.

Science.gov (United States)

Jeon, Jin-Woo; Kim, Jee-Hyun; Lee, Jong-Mook; Lee, Won-Ho; Lee, Do-Young; Paek, Se-Hwan

2014-02-15

To realize an inexpensive, pocket-sized immunosensor system, a rapid test devise based on cross-flow immuno-chromatography was physically combined with a lens-free CMOS image sensor (CIS), which was then applied to the detection of the food-borne pathogen, Salmonella typhimurium (S. typhimurium). Two CISs, each retaining 1.3 mega pixel array, were mounted on a printed circuit board to fabricate a disposable sensing module, being connectable with a signal detection system. For the bacterial analysis, a cellulose membrane-based immunosensing platform, ELISA-on-a-chip (EOC), was employed, being integrated with the CIS module, and the antigen-antibody reaction sites were aligned with the respective sensor. In such sensor construction, the chemiluminescent signals produced from the EOC are transferred directly into the sensors and are converted to electric signals on the detector. The EOC-CIS integrated sensor was capable of detecting a traceable amount of the bacterium (4.22 × 10(3)CFU/mL), nearly comparable to that adopting a sophisticated detector such as cooled-charge-coupled device, while having greatly reduced dimensions and cost. Upon coupling with immuno-magnetic separation, the sensor showed an additional 67-fold enhancement in the detection limit. Furthermore, a real sample test was carried out for fish muscles inoculated with a sample of 3.3CFU S. typhimurium per 10 g, which was able to be detected earlier than 6h after the onset of pre-enrichment by culture. © 2013 Elsevier B.V. All rights reserved.

Assessing Old and New Diagnostic Tests for Gastroesophageal Reflux Disease.

Science.gov (United States)

Vaezi, Michael F; Sifrim, Daniel

2018-01-01

A detailed critique of objective measurements of gastroesophageal reflux disease (GERD) would improve management of patients suspecting of having reflux, leading to rational selection of treatment and better outcomes. Many diagnostic tests for GERD have been developed over the past decades. We analyze their development, positive- and negative-predictive values, and ability to predict response to treatment. These features are important for development of medical, surgical, and endoscopic therapies for GERD. We discuss the value of available diagnostic tests and review their role in management of patients with persistent reflux symptoms despite adequate medical or surgical treatment. This is becoming a significant health economic problem, due to the widespread use of proton pump inhibitors. GERD is believed to cause nonesophageal symptoms, such as those provoked by ear, nose, throat, or respiratory disorders. We analyze the value of GERD diagnostic tests in evaluation of these troublesome, nonesophageal symptoms. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.

Quantitative 89Zr immuno-PET for in vivo scouting of 90Y-labeled monoclonal antibodies in xenograft-bearing nude mice.

NARCIS (Netherlands)

Verel, I.; Visser, G.W.; Boellaard, R.; Boerman, O.C.; Eerd-Vismale, J.E.M. van; Snow, G.B.; Lammertsma, A.A.; Dongen, G.A.M.S. van

2003-01-01

Immuno-PET as a scouting procedure before radioimmunotherapy (RIT) aims at the confirmation of tumor targeting and the accurate estimation of radiation dose delivery to both tumor and normal tissues. Immuno-PET with (89)Zr-labeled monoclonal antibodies (mAbs) and (90)Y-mAb RIT might form such a

Alkaline phosphatase-fused repebody as a new format of immuno-reagent for an immunoassay

Energy Technology Data Exchange (ETDEWEB)

Seo, Hyo-Deok; Lee, Joong-jae [Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 (Korea, Republic of); Kim, Yu Jung [Industrial Biotechnology and Bioenergy Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon (Korea, Republic of); Hantschel, Oliver [School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne (Switzerland); Lee, Seung-Goo [Industrial Biotechnology and Bioenergy Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon (Korea, Republic of); Kim, Hak-Sung, E-mail: hskim76@kaist.ac.kr [Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 (Korea, Republic of)

2017-01-15

Enzyme-linked immunoassays based on an antibody-antigen interaction are widely used in biological and medical sciences. However, the conjugation of an enzyme to antibodies needs an additional chemical process, usually resulting in randomly cross-linked molecules and a loss of the binding affinity and enzyme activity. Herein, we present the development of an alkaline phosphatase-fused repebody as a new format of immuno-reagent for immunoassays. A repebody specifically binding to human TNF-α (hTNF-α) was selected through a phage display, and its binding affinity was increased up to 49 nM using a modular engineering approach. A monomeric alkaline phosphatase (mAP), which was previously isolated from a metagenome library, was genetically fused to the repebody as a signal generator, and the resulting repebody-mAP fusion protein was used for direct and sandwich immunoassays of hTNF-α. We demonstrate the utility and potential of the repebody-mAP fusion protein as an immuno-reagent by showing the sensitivity of 216 pg mL{sup −1} for hTNF-α in a sandwich immunoassay. Furthermore, this repebody-mAP fusion protein enabled the detection of hTNF-α spiked in a serum-supplemented medium with high accuracy and reproducibility. It is thus expected that a mAP-fused repebody can be broadly used as an immuno-reagent in immunoassays. - Highlights: • A human TNF-α (hTNF-α)-specific repebody was selected using a phage display. • A monomeric alkaline phosphatase (mAP) was genetically fused to the repebody. • mAP-fused repebody enabled detection of hTNF-α with high sensitivity and accuracy. • mAP-fused repebody can be widely used as a new immuno-reagent in immunoassays.

Dry Eye Disease: Concordance Between the Diagnostic Tests in African Eyes.

Science.gov (United States)

Onwubiko, Stella N; Eze, Boniface I; Udeh, Nnenma N; Onwasigwe, Ernest N; Umeh, Rich E

2016-11-01

To assess the concordance between the diagnostic tests for dry eye disease (DED) in a Nigerian hospital population. The study was a hospital-based cross-sectional survey of adults (≥18 years) presenting at the eye clinic of the University of Nigeria Teaching Hospital (UNTH), Enugu; September-December, 2011. Participants' socio-demographic data were collected. Each subject was assessed for DED using the "Ocular Surface Disease Index" (OSDI) questionnaire, tear-film breakup time (TBUT), and Schirmer test. The intertest concordance was assessed using kappa statistic, correlation, and regression coefficients. The participants (n=402; men: 193) were aged 50.1±19.1 standard deviation years (range: 18-94 years). Dry eye disease was diagnosed in 203 by TBUT, 170 by Schirmer test, and 295 by OSDI; the concordance between the tests were OSDI versus TBUT (Kappa, κ=-0.194); OSDI versus Schirmer (κ=-0.276); and TBUT versus Schirmer (κ=0.082). Ocular Surface Disease Index was inversely correlated with Schirmer test (Spearman ρ=-0.231, P<0.001) and TBUT (ρ=-0.237, P<0.001). In the linear regression model, OSDI was poorly predicted by TBUT (β=-0.09; 95% confidence interval (CI): -0.26 to -0.03, P=0.14) and Schirmer test (β=-0.35, 95% CI: -0.53 to -0.18, P=0.18). At UNTH, there is poor agreement, and almost equal correlation, between the subjective and objective tests for DED. Therefore, the selection of diagnostic test for DED should be informed by cost-effectiveness and diagnostic resource availability, not diagnostic efficiency or utility.

Genetic test utilization and diagnostic yield in adult patients with neurological disorders.

Science.gov (United States)

Bardakjian, Tanya M; Helbig, Ingo; Quinn, Colin; Elman, Lauren B; McCluskey, Leo F; Scherer, Steven S; Gonzalez-Alegre, Pedro

2018-03-28

To determine the diagnostic yield of different genetic test modalities in adult patients with neurological disorders, we evaluated all adult patients seen for genetic diagnostic evaluation in the outpatient neurology practice at the University of Pennsylvania between January 2016 and April 2017 as part of the newly created Penn Neurogenetics Program. Subjects were identified through our electronic medical system as those evaluated by the Program's single clinical genetic counselor in that period. A total of 377 patients were evaluated by the Penn Neurogenetics Program in different settings and genetic testing recommended. Of those, 182 (48%) were seen in subspecialty clinic setting and 195 (52%) in a General Neurogenetics Clinic. Genetic testing was completed in over 80% of patients in whom it was recommended. The diagnostic yield was 32% across disease groups. Stratified by testing modality, the yield was highest with directed testing (50%) and array comparative genomic hybridization (45%), followed by gene panels and exome testing (25% each). In conclusion, genetic testing can be successfully requested in clinic in a large majority of adult patients. Age is not a limiting factor for a genetic diagnostic evaluation and the yield of clinical testing across phenotypes (almost 30%) is consistent with previous phenotype-focused or research-based studies. These results should inform the development of specific guidelines for clinical testing and serve as evidence to improve reimbursement by insurance payers.

Efficient Noninferiority Testing Procedures for Simultaneously Assessing Sensitivity and Specificity of Two Diagnostic Tests

Directory of Open Access Journals (Sweden)

Guogen Shan

2015-01-01

Full Text Available Sensitivity and specificity are often used to assess the performance of a diagnostic test with binary outcomes. Wald-type test statistics have been proposed for testing sensitivity and specificity individually. In the presence of a gold standard, simultaneous comparison between two diagnostic tests for noninferiority of sensitivity and specificity based on an asymptotic approach has been studied by Chen et al. (2003. However, the asymptotic approach may suffer from unsatisfactory type I error control as observed from many studies, especially in small to medium sample settings. In this paper, we compare three unconditional approaches for simultaneously testing sensitivity and specificity. They are approaches based on estimation, maximization, and a combination of estimation and maximization. Although the estimation approach does not guarantee type I error, it has satisfactory performance with regard to type I error control. The other two unconditional approaches are exact. The approach based on estimation and maximization is generally more powerful than the approach based on maximization.

Comparison of core-shell and totally porous ultra high performance liquid chromatographic stationary phases based on their selectivity towards alfuzosin compounds.

Science.gov (United States)

Szulfer, Jarosław; Plenis, Alina; Bączek, Tomasz

2014-06-13

This paper focuses on the application of a column classification system based on the Katholieke Universiteit Leuven for the characterization of physicochemical properties of core-shell and ultra-high performance liquid chromatographic stationary phases, followed by the verification of the reliability of the obtained column classification in pharmaceutical practice. In the study, 7 stationary phases produced in core-shell technology and 18 ultra-high performance liquid chromatographic columns were chromatographically tested, and ranking lists were built on the FKUL-values calculated against two selected reference columns. In the column performance test, an analysis of alfuzosin in the presence of related substances was carried out using the brands of the stationary phases with the highest ranking positions. Next, a system suitability test as described by the European Pharmacopoeia monograph was performed. Moreover, a study was also performed to achieve a purposeful shortening of the analysis time of the compounds of interest using the selected stationary phases. Finally, it was checked whether methods using core-shell and ultra-high performance liquid chromatographic columns can be an interesting alternative to the high-performance liquid chromatographic method for the analysis of alfuzosin in pharmaceutical practice. Copyright © 2014 Elsevier B.V. All rights reserved.

Compounding diagnostic delays: a qualitative study of point-of-care testing in South Africa.

Science.gov (United States)

Engel, Nora; Davids, Malika; Blankvoort, Nadine; Pai, Nitika Pant; Dheda, Keertan; Pai, Madhukar

2015-04-01

Successful point-of-care (POC) testing (completion of test-and-treat cycle in one patient encounter) has immense potential to reduce diagnostic and treatment delays, and improve patient and public health outcomes. We explored what tests are done and how in public/private, rural/urban hospitals and clinics in South Africa and whether they can ensure successful POC testing. This qualitative research study examined POC testing across major diseases in Cape Town, Durban and Eastern Cape. We conducted 101 semi-structured interviews and seven focus group discussions with doctors, nurses, community health workers, patients, laboratory technicians, policymakers, hospital managers and diagnostic manufacturers. In South Africa, diagnostics are characterised by a centralised system. Most tests conducted on the spot can be made to work successfully as POC tests. The majority of public/private clinics and smaller hospitals send samples via couriers to centralised laboratories and retrieve results the same way, via internet, fax or phone. The main challenge to POC testing lies in transporting samples and results, while delays risk patient loss from diagnostic/treatment pathways. Strategies to deal with associated delays create new problems, such as artificially prolonged turnaround times, strains on human resources and quality of testing, compounding additional diagnostic and treatment delays. For POC testing to succeed, particular characteristics of diagnostic ecosystems and adaptations of professional practices to overcome associated challenges must be taken into account. © 2014 John Wiley & Sons Ltd.

Industrial scale chromatographic separation of valuable compounds from biomass hydrolysates and side streams

Energy Technology Data Exchange (ETDEWEB)

Saari, P.

2011-06-15

Carbohydrates are composed of a number of various monosaccharides, glucose being the most abundant. Some of the monosaccharides are valuable compounds used in the food and pharmaceutical industries. They can be separated from biomass hydrolysates e.g. by chromatographic methods. In this thesis, chromatographic separation of valuable compounds using ion exchange resins was studied on an industrial scale. Of special interest were rare monosaccharides in biomass hydrolysates. A novel chromatographic separation process was developed for fucose, starting from pre-processed spent sulfite liquor. The core of the process consists of three chromatographic separations with different types of ion exchange resins. Chromatographic separation of galactose was tested with three biomass hydrolysates; lactose, gum arabic and hemicellulose hydrolysates. It was demonstrated that also galactose can be separated from complex carbohydrate mixtures. A recovery process for arabinose from citrus pectin liquid residual and for mannose from wood pulp hydrolysate were also developed and experimentally verified. In addition to monosaccharides, chromatographic separation of glycinebetaine from vinasse was examined with a hydrogen form weak acid cation exchange resin. The separation involves untypical peak formation depending, for example, on the pH and the cation composition. The retention mechanism was found to be hydrogen bonding between glycinebetaine and the resin. In the experimental part, all four resin types - strong acid cation, strong base anion, weak acid cation and weak base anion exchange resins - were used. In addition, adsorption equilibria data of seven monosaccharides and sucrose were measured with the resins in sodium and sulfate forms because such data have been lacking. It was found out that the isotherms of all sugars were linear under industrial conditions. A systematic method for conceptual process design and sequencing of chromatographic separation steps were developed

A comparison of rapid diagnostic testing (by plasmodium lactate ...

African Journals Online (AJOL)

Background: The World Health Organization (WHO) considers early and rapid diagnosis as one of the strategies to control malaria. This study compared the performance of Quantitative Buffy Coat (QBC) test and the Plasmodium lactate dehydrogenase (pLDH) rapid diagnostic test (RDT) with microscopy as the gold ...

Technology diffusion and diagnostic testing for prostate cancer

Science.gov (United States)

Schroeck, Florian R.; Kaufman, Samuel R.; Jacobs, Bruce L.; Skolarus, Ted A.; Miller, David C.; Weizer, Alon Z.; Montgomery, Jeffrey S.; Wei, John T.; Shahinian, Vahakn B.; Hollenbeck, Brent K.

2013-01-01

Purpose While the dissemination of robotic prostatectomy and intensity-modulated radiotherapy (IMRT) may fuel increased use of prostatectomy and radiotherapy, these new technologies may also have spillover effects related to diagnostic testing for prostate cancer. Therefore, we examined the association of regional technology penetration with receipt of prostate specific antigen (PSA) testing and prostate biopsy. Methods In this retrospective cohort study, we included 117,857 men age 66 and older from the 5% sample of Medicare beneficiaries living in the Surveillance Epidemiology and End Results (SEER) areas from 2003 – 2007. Regional technology penetration was measured as the number of providers performing robotic prostatectomy or IMRT per population in a healthcare market (i.e., hospital referral region). We assessed the association of technology penetration with rates of PSA testing and prostate biopsy with generalized estimating equations. Results High technology penetration was associated with increased rates of PSA testing (442 versus 425 per 1,000 person-years, pimpact of technology penetration on PSA testing and prostate biopsy was much smaller than the effect of age, race, and comorbidity (e.g., PSA testing rate per 1,000 person-years: 485 versus 373 for men with only one versus 3+ co-morbid conditions, ppenetration was associated with slightly higher rates of PSA testing and no change in prostate biopsy rates. Collectively, our findings temper concerns that adoption of new technology accelerates diagnostic testing for prostate cancer. PMID:23669564

Evaluation of Diagnostic Tests Using Information Theory for Multi-Class Diagnostic Problems and its Application for the Detection of Occlusal Caries Lesions

Directory of Open Access Journals (Sweden)

Umut Arslan

2014-09-01

Full Text Available Background: Several methods are available to evaluate the performance of the tests when the purpose of the diagnostic test is to discriminate between two possible disease states. However multi-class diagnostic problems frequently appear in many areas of medical science. Hence, there is a need for methods which will enable us to characterize the accuracy of diagnostic tests when there are more than two possible disease states. Aims: To show that two information theory measures, information content (IC and proportional reduction in diagnostic uncertainty (PRDU, can be used for the evaluation of the performance of diagnostic tests for multi-class diagnostic problems that may appear in different areas of medical science. Study Design: Diagnostic accuracy study. Methods: Sixty freshly extracted permanent human molar and premolar teeth suspected to have occlusal caries lesions were selected for the study and were assessed by two experienced examiners. Each examiner performed two evaluations. Histological examination was used as the gold standard. The scores of the histological examination were defined as sound (n=11, enamel caries (n=22 and dentin caries (n=27. Diagnostic performance of i visual inspection, ii radiography, iii laser fluorescence (LF and iv micro-computed tomography (M-CT caries detection methods was evaluated by calculating IC and PRDU. Results: Micro-computed tomography examination was the best method among the diagnostic techniques for the diagnosis of occlusal caries in terms of both IC and PRDU. M-CT examination supplied the maximum diagnostic information about the diagnosis of occlusal caries in the first (IC: 1.056; p<0.05, (PRDU: 70.5% and second evaluation (IC: 1.105; p<0.05, (PRDU: 73.8% for the first examiner. M-CT examination was the best method among the diagnostic techniques for the second examiner in both the first (IC:1.105; p<0.05, (PRDU:73.8% and second evaluation (IC:1.061; p<0.05, (PRDU:70.8%. IC and PRDU were

Cancer-Associated Fibroblasts from lung tumors maintain their immuno-suppressive abilities after high-dose irradiation

Directory of Open Access Journals (Sweden)

Laia eGorchs

2015-05-01

Full Text Available Accumulating evidence supports the notion that high-dose (>5 Gy radiotherapy (RT regimens are triggering stronger pro-immunogenic effects than standard low-dose (2 Gy regimens. However, the effects of RT on certain immunoregulatory elements in tumors remain unexplored. In this study we have investigated the effects of high-dose irradiation (HD-RT on the immunomodulating functions of cancer-associated fibroblasts (CAFs. Primary CAF cultures were established from lung cancer specimens derived from patients diagnosed for non-small cell lung cancer. Irradiated and non-irradiated CAFs were examined for immunomodulation in experiments with peripheral blood mononuclear cells from random, healthy donors. Regulation of lymphocytes behavior was checked by lymphocyte proliferation assays, lymphocyte migration assays and T-cell cytokine production. Additionally, CAF-secreted immuno-regulatory factors were studied by multiplex protein arrays, ELISAs and by LC-MS/MS proteomics. In all functional assays we observed a powerful immuno-suppressive effect exerted by CAF-conditioned medium on activated T-cells (p>0,001, and this effect was sustained after a single radiation dose of 18 Gy. Relevant immuno-suppressive molecules such as prostaglandin E2, interleukin-6 and -10, or transforming growth factor-β were found in CAF conditioned medium, but their secretion was unchanged after irradiation. Finally, immunogenic cell death responses in CAFs were studied by exploring the release of high motility group box-1 and ATP. Both alarmins remained undetectable before and after irradiation. In conclusion, CAFs play a powerful immuno-suppressive effect over activated T-cells, and this effect remains unchanged after HD-RT. Importantly, CAFs do not switch on immunogenic cell death responses after exposure to HD-RT.

Cost Implications of Value-Based Pricing for Companion Diagnostic Tests in Precision Medicine.

Science.gov (United States)

Zaric, Gregory S

2016-07-01

Many interpretations of personalized medicine, also referred to as precision medicine, include discussions of companion diagnostic tests that allow drugs to be targeted to those individuals who are most likely to benefit or that allow treatment to be designed in a way such that individuals who are unlikely to benefit do not receive treatment. Many authors have commented on the clinical and competitive implications of companion diagnostics, but there has been relatively little formal analysis of the cost implications of companion diagnostics, although cost reduction is often cited as a significant benefit of precision medicine. We investigate the potential impact on costs of precision medicine implemented through the use of companion diagnostics. We develop a framework in which the costs of companion diagnostic tests are determined by considerations of profit maximization and cost effectiveness. We analyze four scenarios that are defined by the incremental cost-effectiveness ratio of the new drug in the absence of a companion diagnostic test. We find that, in most scenarios, precision medicine strategies based on companion diagnostics should be expected to lead to increases in costs in the short term and that costs would fall only in a limited number of situations.

Evaluation of instant cup noodle, irradiated for immuno-compromised patients

International Nuclear Information System (INIS)

Lee, Ji-Hye; Kim, Jae-Kyung; Park, Jae-Nam; Yoon, Young-Min; Sung, Nak-Yun; Kim, Jae-Hun; Song, Beom-Seok; Yook, Hong-Sun; Kim, Byeong-Keun; Lee, Ju-Woon

2012-01-01

In the present study, initial microbial load of instant cup noodle (ICN) was investigated and gamma irradiation applied to develop immuno-compromised patients food for their safe consumption. The initial microbial population of dried vegetable and meat, and noodle was below the detection limit (1 log CFU/g); however, that of seasoning powder was just above 4 log CFU/g. Moreover, rehydrated-ICN with water at 100 °C still show above 3 log CFU/g of microbial load, which indicates the need for an additional process to control microbial safety of the seasoning powder. The total aerobic bacteria in seasoning powder and rehydrated-ICN could be controlled with 17 kGy gamma irradiation. This result referred 17 kGy gamma irradiation could reach ‘practical sterility’ of ICN. The overall difference in sensory properties between the non-irradiated and irradiated ICN was insignificant. Thus, gamma irradiation could improve the microbial quality of ICN, and reduce the risk of infection posed by the seasoning powder, without any adverse effects on their sensory quality. These results suggest that gamma-irradiated ICN can be used as a snack food for immuno-compromised patients.

Evaluation of instant cup noodle, irradiated for immuno-compromised patients

Science.gov (United States)

Lee, Ji-Hye; Kim, Jae-Kyung; Park, Jae-Nam; Yoon, Young-Min; Sung, Nak-Yun; Kim, Jae-Hun; Song, Beom-Seok; Yook, Hong-Sun; Kim, Byeong-Keun; Lee, Ju-Woon

2012-08-01

In the present study, initial microbial load of instant cup noodle (ICN) was investigated and gamma irradiation applied to develop immuno-compromised patients food for their safe consumption. The initial microbial population of dried vegetable and meat, and noodle was below the detection limit (1 log CFU/g); however, that of seasoning powder was just above 4 log CFU/g. Moreover, rehydrated-ICN with water at 100 °C still show above 3 log CFU/g of microbial load, which indicates the need for an additional process to control microbial safety of the seasoning powder. The total aerobic bacteria in seasoning powder and rehydrated-ICN could be controlled with 17 kGy gamma irradiation. This result referred 17 kGy gamma irradiation could reach 'practical sterility' of ICN. The overall difference in sensory properties between the non-irradiated and irradiated ICN was insignificant. Thus, gamma irradiation could improve the microbial quality of ICN, and reduce the risk of infection posed by the seasoning powder, without any adverse effects on their sensory quality. These results suggest that gamma-irradiated ICN can be used as a snack food for immuno-compromised patients.

Developing and Standardization of a Diagnostic Reading Test

Directory of Open Access Journals (Sweden)

Tahereh Sima-Shirazi

2004-06-01

Full Text Available Objective: This paper is a report on the development, structure and content of a diagnostic dyslexia reading test. The target population of this test is persian children who have problems in learning reading and may be considered as dyslexic. This diagnostic test is the first reading test developed for the native speakers of persian. Materials & Methods: The theoretical framework of the test is based on two well- established reading tests for the English speaking children, namely Durrell Analysis of Reading and Neale Analysis of Reading Ability. The linguistic content of the subtests is selected from the vocabulary and texts of the textbook used in the primary schools. Both the vocabulary and the sentences of the parrallel passeges were controlled for frequency, phonemic/graphemic regularity, syllable structure, morphology, syntax and semantics. They were also controlled for value judgement by two linguistics and three first grader teachers.The first version of the test is normed on 605 boy and girl first graders from different educational sectors and schools selected randomly.The method used in this research is cross- sectional, descriptive- analytic and the data analysis is based on pearson, and mann-whitney u. Results: Reliability of the test is calculated based on parrallel forms (~ 90% and validity is based on content validity.This test has a supplementary section including spelling, graphem/ phoneme correspondness, nonword reading, irregular word reading, and copy subtests. Conclusion: Considering highreliability and precise validation of the test it can be used to diagnose the dyslexia and related linguistic impairments.

Systematic reviews of diagnostic tests in endocrinology: an audit of methods, reporting, and performance.

Science.gov (United States)

Spencer-Bonilla, Gabriela; Singh Ospina, Naykky; Rodriguez-Gutierrez, Rene; Brito, Juan P; Iñiguez-Ariza, Nicole; Tamhane, Shrikant; Erwin, Patricia J; Murad, M Hassan; Montori, Victor M

2017-07-01

Systematic reviews provide clinicians and policymakers estimates of diagnostic test accuracy and their usefulness in clinical practice. We identified all available systematic reviews of diagnosis in endocrinology, summarized the diagnostic accuracy of the tests included, and assessed the credibility and clinical usefulness of the methods and reporting. We searched Ovid MEDLINE, EMBASE, and Cochrane CENTRAL from inception to December 2015 for systematic reviews and meta-analyses reporting accuracy measures of diagnostic tests in endocrinology. Experienced reviewers independently screened for eligible studies and collected data. We summarized the results, methods, and reporting of the reviews. We performed subgroup analyses to categorize diagnostic tests as most useful based on their accuracy. We identified 84 systematic reviews; half of the tests included were classified as helpful when positive, one-fourth as helpful when negative. Most authors adequately reported how studies were identified and selected and how their trustworthiness (risk of bias) was judged. Only one in three reviews, however, reported an overall judgment about trustworthiness and one in five reported using adequate meta-analytic methods. One in four reported contacting authors for further information and about half included only patients with diagnostic uncertainty. Up to half of the diagnostic endocrine tests in which the likelihood ratio was calculated or provided are likely to be helpful in practice when positive as are one-quarter when negative. Most diagnostic systematic reviews in endocrine lack methodological rigor, protection against bias, and offer limited credibility. Substantial efforts, therefore, seem necessary to improve the quality of diagnostic systematic reviews in endocrinology.

A general diagnostic model applied to language testing data.

Science.gov (United States)

von Davier, Matthias

2008-11-01

Probabilistic models with one or more latent variables are designed to report on a corresponding number of skills or cognitive attributes. Multidimensional skill profiles offer additional information beyond what a single test score can provide, if the reported skills can be identified and distinguished reliably. Many recent approaches to skill profile models are limited to dichotomous data and have made use of computationally intensive estimation methods such as Markov chain Monte Carlo, since standard maximum likelihood (ML) estimation techniques were deemed infeasible. This paper presents a general diagnostic model (GDM) that can be estimated with standard ML techniques and applies to polytomous response variables as well as to skills with two or more proficiency levels. The paper uses one member of a larger class of diagnostic models, a compensatory diagnostic model for dichotomous and partial credit data. Many well-known models, such as univariate and multivariate versions of the Rasch model and the two-parameter logistic item response theory model, the generalized partial credit model, as well as a variety of skill profile models, are special cases of this GDM. In addition to an introduction to this model, the paper presents a parameter recovery study using simulated data and an application to real data from the field test for TOEFL Internet-based testing.

Probabilistic peak detection for first-order chromatographic data

NARCIS (Netherlands)

Lopatka, M.; Vivó-Truyols, G.; Sjerps, M.J.

2014-01-01

We present a novel algorithm for probabilistic peak detection in first-order chromatographic data. Unlike conventional methods that deliver a binary answer pertaining to the expected presence or absence of a chromatographic peak, our method calculates the probability of a point being affected by

Common pitfalls in statistical analysis: Understanding the properties of diagnostic tests - Part 1.

Science.gov (United States)

Ranganathan, Priya; Aggarwal, Rakesh

2018-01-01

In this article in our series on common pitfalls in statistical analysis, we look at some of the attributes of diagnostic tests (i.e., tests which are used to determine whether an individual does or does not have disease). The next article in this series will focus on further issues related to diagnostic tests.

Comparison of Premier CAMPY Enzyme Immunoassay (EIA), ProSpecT Campylobacter EIA, and ImmunoCard STAT! CAMPY Tests with Culture for Laboratory Diagnosis of Campylobacter Enteric Infections ▿ †

Science.gov (United States)

Granato, Paul A.; Chen, Li; Holiday, Iris; Rawling, Russell A.; Novak-Weekley, Susan M.; Quinlan, Tammy; Musser, Kimberlee A.

2010-01-01

Campylobacter enteritis is a food-borne or waterborne illness caused almost exclusively by Campylobacter jejuni and, to a lesser extent, by Campylobacter coli. These organisms produce indistinguishable clinical diseases and together represent the second most common cause of bacterial diarrhea in the United States and the leading cause of enteric infection throughout the world. The conventional approach to the laboratory diagnosis of Campylobacter enteritis is based on the recovery of the organism from a stool specimen, which requires the use of a specialized medium incubated at 42°C for several days in an artificially created microaerophilic environment. Recently, several commercially available enzyme immunoassays (EIAs) have been developed for the direct detection of C. jejuni and C. coli in stool specimens. This study compared conventional culture with three EIA methods, the Premier CAMPY EIA (Meridian Bioscience, Cincinnati, OH), the ProSpecT Campylobacter EIA (Remel, Lenexa, KS), and the ImmunoCard STAT! CAMPY test (Meridian Bioscience, Cincinnati, OH), for the detection of C. jejuni and C. coli in 485 patient stool samples. Discordant results were arbitrated by using an in-house, real-time PCR assay that was developed and validated by a public health reference laboratory. Following analyses of the discrepant specimens by PCR, the sensitivity and specificity of both the Premier CAMPY and ProSpecT Campylobacter EIAs were 99.3% and 98%, respectively, while the ImmunoCard STAT! CAMPY test had a sensitivity of 98.5% and a specificity of 98.2%. By use of the PCR test as the reference standard, culture detected 127 of 135 Campylobacter-positive stool specimens, yielding a sensitivity of 94.1%. These results showed that the three EIAs evaluated in this study provide a rapid and reliable alternative for the laboratory diagnosis of enteric infections with C. jejuni and C. coli and that conventional culture may no longer be recognized as the “gold standard” for

Diagnostic development and support of MHD (magnetohydrodynamics) test facilities

Energy Technology Data Exchange (ETDEWEB)

1989-07-01

Mississippi State University (MSU) is developing diagnostic instruments for Magnetohydrodynamics (MHD) power train data acquisition and for support of MHD component development test facilities. Microprocessor-controlled optical instruments, initially developed for HRSR support, are being refined, and new systems to measure temperatures and gas-seed-slag stream characteristics are being developed. To further data acquisition and analysis capabilities, the diagnostic systems are being interfaced with MHD Energy Center computers. Technical support for the diagnostic needs of the national MHD research effort is being provided. MSU personnel will also cooperate with government agencies and private industries to improve the transformation of research and development results into processes, products and services applicable to their needs.

The glucose breath test: a diagnostic test for small bowel stricture(s) in Crohn's disease.

Science.gov (United States)

Mishkin, Daniel; Boston, Francis M; Blank, David; Yalovsky, Morty; Mishkin, Seymour

2002-03-01

The aim of this study was to determine whether an indirect noninvasive indicator of proximal bacterial overgrowth, the glucose breath test, was of diagnostic value in inflammatory bowel disease. Twenty four of 71 Crohn's disease patients tested had a positive glucose breath test. No statistical conclusions could be drawn between the Crohn's disease activity index and glucose breath test status. Of patients with radiologic evidence of small bowel stricture(s), 96.0% had a positive glucose breath test, while only one of 46 negative glucose breath test patients had a stricture. The positive and negative predictive values for a positive glucose breath test as an indicator of stricture formation were 96.0% and 97.8%, respectively. This correlation was not altered in Crohn's disease patients with fistulae or status postresection of the terminal ileum. The data in ulcerative colitis were nondiagnostic. In conclusion, the glucose breath test appears to be an accurate noninvasive inexpensive diagnostic test for small bowel stricture(s) and secondary bacterial overgrowth in Crohn's disease.

30 CFR 250.520 - When do I have to perform a casing diagnostic test?

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false When do I have to perform a casing diagnostic... Operations Casing Pressure Management § 250.520 When do I have to perform a casing diagnostic test? (a) You must perform a casing diagnostic test within 30 days after first observing or imposing casing pressure...

[Pathogenic Mechanism and Diagnostic Testing for Drug Allergies].

Science.gov (United States)

Uno, Katsuji

2018-01-01

　Three stages of the pathogenic mechanism of drug allergies can be considered: antigen formation, immune reaction and inflammation/disorder reaction. Drugs are thought to form 4 types of antigens: drug only, polymers, drug-carrier conjugates, and metabolite-carrier complexes. Antigens are recognized by B cell receptors and T cell receptors. Helper T cells (Th) are differentiated into four subsets, namely, Th1, Th2, Th17 and regulatory T cells (Treg). Th1 produces interleukin (IL)-2 and interferon (IFN)-γ, and activates macrophages and cytotoxic T cells (Tc). Macrophages induce type IV allergies, and Tc lead to serious type IV allergies. On the other hand, Th2 produces IL-4, IL-5, and IL-6, etc., and activates B cells. B cells produce IgE antibodies, and the IgE antibody affects mast cells and induces type I allergies. Activated eosinophil leads to the chronic state of type I allergy. Diagnostic testing for allergenic drugs is necessary for patients with drug allergies. Because in vivo diagnostic tests for allergenic drugs are associated with a risk and burden to the patient, in vitro allergy tests are recommended to identify allergenic drugs. In allergy tests performed in vitro, cytological tests are more effective than serological tests, and the leukocyte migration test (LMT) presently has the highest efficacy. An LMT-chamber is better than LMT-agarose in terms of usability and sensitivity, and it can detect about 80% of allergenic drugs.

Get the Diagnosis: an evidence-based medicine collaborative Wiki for diagnostic test accuracy.

Science.gov (United States)

Hammer, Mark M; Kohlberg, Gavriel D

2017-04-01

Despite widespread calls for its use, there are challenges to the implementation of evidence-based medicine (EBM) in clinical practice. In response to the challenges of finding timely, pertinent information on diagnostic test accuracy, we developed an online, crowd-sourced Wiki on diagnostic test accuracy called Get the Diagnosis (GTD, http://www.getthediagnosis.org). Since its launch in November 2008 till October 2015, GTD has accumulated information on 300 diagnoses, with 1617 total diagnostic entries. There are a total of 1097 unique diagnostic tests with a mean of 5.4 tests (range 0-38) per diagnosis. 73% of entries (1182 of 1617) have an associated sensitivity and specificity and 89% of entries (1432 of 1617) have associated peer-reviewed literature citations. Altogether, GTD contains 474 unique literature citations. For a sample of three diagnoses, the search precision (percentage of relevant results in the first 30 entries) in GTD was 100% as compared with a range of 13.3%-63.3% for PubMed and between 6.7% and 76.7% for Google Scholar. GTD offers a fast, precise and efficient way to look up diagnostic test accuracy. On three selected examples, GTD had a greater precision rate compared with PubMed and Google Scholar in identifying diagnostic test information. GTD is a free resource that complements other currently available resources. 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/.

Community Laboratory Testing for Cryptosporidium: Multicenter Study Retesting Public Health Surveillance Stool Samples Positive for Cryptosporidium by Rapid Cartridge Assay with Direct Fluorescent Antibody Testing.

Directory of Open Access Journals (Sweden)

Dawn M Roellig

Full Text Available Cryptosporidium is a common cause of sporadic diarrheal disease and outbreaks in the United States. Increasingly, immunochromatography-based rapid cartridge assays (RCAs are providing community laboratories with a quick cryptosporidiosis diagnostic method. In the current study, the Centers for Disease Control and Prevention (CDC, the Association of Public Health Laboratories (APHL, and four state health departments evaluated RCA-positive samples obtained during routine Cryptosporidium testing. All samples underwent "head to head" re-testing using both RCA and direct fluorescence assay (DFA. Community level results from three sites indicated that 54.4% (166/305 of Meridian ImmunoCard STAT! positives and 87.0% (67/77 of Remel Xpect positives were confirmed by DFA. When samples were retested by RCA at state laboratories and compared with DFA, 83.3% (155/186 of Meridian ImmunoCard STAT! positives and 95.2% (60/63 of Remel Xpect positives were confirmed. The percentage of confirmed community results varied by site: Minnesota, 39.0%; New York, 63.9%; and Wisconsin, 72.1%. The percentage of confirmed community results decreased with patient age; 12.5% of community positive tests could be confirmed by DFA for patients 60 years of age or older. The percentage of confirmed results did not differ significantly by sex, storage temperature, time between sample collection and testing, or season. Findings from this study demonstrate a lower confirmation rate of community RCA positives when compared to RCA positives identified at state laboratories. Elucidating the causes of decreased test performance in order to improve overall community laboratory performance of these tests is critical for understanding the epidemiology of cryptosporidiosis in the United States (US.

What is the role of clinical tests and ultrasound in acetabular labral tear diagnostics?

DEFF Research Database (Denmark)

Troelsen, Anders; Mechlenburg, Inger; Gelineck, John

2009-01-01

BACKGROUND AND PURPOSE: An acetabular labral tear is a diagnostic challenge. Various clinical tests have been described, but little is known about their diagnostic sensitivity and specificity. We investigated the diagnostic validity of clinical tests and ultrasound as compared with MR arthrography...... no or only slight signs of osteoarthritis (Tönnis grade 0-1). RESULTS: MR arthrography identified labral tears in 17 of the 18 hips. Ultrasound had a sensitivity of 94%, a positive predictive value of 94%, and was false negative in only 1 case compared to MR arthrography. The impingement test had the best...... diagnostic ability of the clinical tests, with a sensitivity of 59% and a specificity of 100%. The positive predictive value was 100% while the negative predictive value was 13%. INTERPRETATION: The impingement test is helpful in identifying acetabular labral tears. If this test is negative and if a labral...

Coffee contains cholinomimetic compound distinct from caffeine. I: Purification and chromatographic analysis.

Science.gov (United States)

Tse, S Y

1991-07-01

Both regular and decaffeinated coffees were found to have cholinomimetic actions when tested in urethane-anesthetized rats. These actions were distinct from those of caffeine and reversible by atropine. The bioactive fraction was purified from alcoholic extracts of instant decaffeinated coffee by liquid column chromatography and preparative TLC. The purified compound showed similar pharmacological actions as the starting material. Chromatographic behavior was further characterized by analytical TLC and HPLC. Chromatographic analyses of extracts of green coffee beans and roasted ground coffees showed that the cardioactive compound was only present in roasted coffees. Similar analyses of other commonly consumed beverages, including teas and cocoa, showed that this compound was not present in beverages besides coffee.

Technology diffusion and diagnostic testing for prostate cancer.

Science.gov (United States)

Schroeck, Florian R; Kaufman, Samuel R; Jacobs, Bruce L; Skolarus, Ted A; Miller, David C; Weizer, Alon Z; Montgomery, Jeffrey S; Wei, John T; Shahinian, Vahakn B; Hollenbeck, Brent K

2013-11-01

While the dissemination of robotic prostatectomy and intensity modulated radiotherapy may fuel the increased use of prostatectomy and radiotherapy, these new technologies may also have spillover effects related to diagnostic testing for prostate cancer. Therefore, we examined the association of regional technology penetration with the receipt of prostate specific antigen testing and prostate biopsy. In this retrospective cohort study we included 117,857 men 66 years old or older from the 5% sample of Medicare beneficiaries living in Surveillance, Epidemiology and End Results (SEER) areas from 2003 to 2007. Regional technology penetration was measured as the number of providers performing robotic prostatectomy or intensity modulated radiotherapy per population in a health care market, ie hospital referral region. We assessed the association of technology penetration with the prostate specific antigen testing rate and prostate biopsy using generalized estimating equations. High technology penetration was associated with an increased rate of prostate specific antigen testing (442 vs 425/1,000 person-years, pimpact of technology penetration on prostate specific antigen testing and prostate biopsy was much less than the effect of age, race and comorbidity, eg the prostate specific antigen testing rate per 1,000 person-years was 485 vs 373 for men with only 1 vs 3+ comorbid conditions (ppenetration is associated with a slightly higher rate of prostate specific antigen testing and no change in the prostate biopsy rate. Collectively, our findings temper concerns that adopting new technology accelerates diagnostic testing for prostate cancer. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Requirements for appropriate evaluation of diagnostic tests in suspected pulmonary embolism

NARCIS (Netherlands)

Sanson, B. J.; Meinders, A. J.; Kraaijenhagen, R. A.; van Beek, E. J.; Büller, H. R.

1999-01-01

In contrast to the development of new drugs, strict guidelines for the development of new diagnostic methods do not exist. A diagnostic test can be made available without proper evaluation of its clinical utility, which can lead to its premature introduction and inappropriate use. In this review

Beam Diagnostics for the BNL Energy Recovery Linac Test Facility

International Nuclear Information System (INIS)

Cameron, Peter; Ben-Zvi, Ilan; Blaskiewicz, Michael; Brennan, Michael; Connolly, Roger; Dawson, William; Degen, Chris; DellaPenna, Al; Gassner, David; Kesselman, Martin; Kewish, Jorg; Litvinenko, Vladimir; Mead, Joseph; Oerter, Brian; Russo, Tom; Vetter, Kurt; Yakimenko, Vitaly

2004-01-01

An Energy Recovery Linac (ERL) test facility is presently under construction at BNL. The goals of this test facility are first to demonstrate stable intense CW electron beam with parameters typical for the RHIC e-cooling project (and potentially for eRHIC), second to test novel elements of the ERL (high current CW photo-cathode, superconducting RF cavity with HOM dampers, and feedback systems), and finally to test lattice dependence of stability criteria. Planned diagnostics include position monitors, loss monitors, transverse profile monitors (both optical and wires), scrapers/halo monitors, a high resolution differential current monitor, phase monitors, an energy spread monitor, and a fast transverse monitor (for beam break-up studies and the energy feedback system). We discuss diagnostics challenges that are unique to this project, and present preliminary system specifications. In addition, we include a brief discussion of the timing system

Bovine paratuberculosis: a review of the advantages and disadvantages of different diagnostic tests.

Science.gov (United States)

Gilardoni, Liliana R; Paolicchi, Fernando A; Mundo, Silvia L

2012-01-01

Paratuberculosis (PTB), or Johne's disease, is a chronic infectious granulomatous enteritis of ruminants, caused by Mycobacterium avium subspecies paratuberculosis (Map). It is characterized by diarrhea and progressive cachexia, which may cause the death of the animal. Calves are the most susceptible to infection. Infected animals excrete Map mainly by the feces. PTB is endemic worldwide, with high prevalence levels, strong economic impact and public health relevance because of its possible association with Crohn's disease. Although the current reference diagnostic test is identification of Map in the bacterial culture, there are different diagnostic tests to identify infected individuals and/or herds. The sensitivity and specificity of these tests vary according to the stage of the disease in the animals to be evaluated. The correct choice and application of each of these diagnostic tests will ensure their success and may allow to establish a control program. The aim of this work is to review and discuss the different diagnostic tests used in the detection of Map-infected animals, focusing on their advantages and disadvantages.

Divergence-based tests for model diagnostic

Czech Academy of Sciences Publication Activity Database

Hobza, Tomáš; Esteban, M. D.; Morales, D.; Marhuenda, Y.

2008-01-01

Roč. 78, č. 13 (2008), s. 1702-1710 ISSN 0167-7152 R&D Projects: GA MŠk 1M0572 Grant - others:Instituto Nacional de Estadistica (ES) MTM2006-05693 Institutional research plan: CEZ:AV0Z10750506 Keywords : goodness of fit * devergence statistics * GLM * model checking * bootstrap Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 0.445, year: 2008 http://library.utia.cas.cz/separaty/2008/SI/hobza-divergence-based%20tests%20for%20model%20diagnostic.pdf

Real-time remote diagnostic monitoring test-bed in JET

International Nuclear Information System (INIS)

Castro, R.; Kneupner, K.; Vega, J.; De Arcas, G.; Lopez, J.M.; Purahoo, K.; Murari, A.; Fonseca, A.; Pereira, A.; Portas, A.

2010-01-01

Based on the remote experimentation concept oriented to long pulse shots, a test-bed system has been implemented in JET. Its main functionality is the real-time monitoring, on remote, of a reflectometer diagnostic, to visualize different data outputs and status information. The architecture of the system is formed by: the data generator components, the data distribution system, an access control service, and the client applications. In the test-bed there is one data generator, which is the acquisition equipment associated with the reflectometer diagnostic that generates data and status information. The data distribution system has been implemented using a publishing-subscribing technology that receives data from data generators and redistributes them to client applications. And finally, for monitoring, a client application based on JAVA Web Start technology has been used. There are three interesting results from this project. The first one is the analysis of different aspects (data formats, data frame rate, data resolution, etc) related with remote real-time diagnostic monitoring oriented to long pulse experiments. The second one is the definition and implementation of an architecture, flexible enough to be applied to different types of data generated from other diagnostics, and that fits with remote access requirements. Finally, the third result is a secure system, taking into account internal networks and firewalls aspects of JET, and securing the access from remote users. For this last issue, PAPI technology has been used, enabling access control based on user attributes, enabling mobile users to monitor diagnostics in real-time, and enabling the integration of this service into the EFDA Federation (Castro et al., 2008 ).

Real-time remote diagnostic monitoring test-bed in JET

Energy Technology Data Exchange (ETDEWEB)

Castro, R., E-mail: rodrigo.castro@ciemat.e [Asociacion EURATOM/CIEMAT para Fusion, Madrid (Spain); Kneupner, K. [EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Vega, J. [Asociacion EURATOM/CIEMAT para Fusion, Madrid (Spain); De Arcas, G.; Lopez, J.M. [Universidad Politecnica de Madrid, Grupo I2A2, Madrid (Spain); Purahoo, K. [EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Murari, A. [Associazione EURATOM-ENEA per la Fusione, Consorzio RFX, 4-35127 Padova (Italy); Fonseca, A. [Associacao EURATOM/IST, Lisbon (Portugal); Pereira, A.; Portas, A. [Asociacion EURATOM/CIEMAT para Fusion, Madrid (Spain)

2010-07-15

Based on the remote experimentation concept oriented to long pulse shots, a test-bed system has been implemented in JET. Its main functionality is the real-time monitoring, on remote, of a reflectometer diagnostic, to visualize different data outputs and status information. The architecture of the system is formed by: the data generator components, the data distribution system, an access control service, and the client applications. In the test-bed there is one data generator, which is the acquisition equipment associated with the reflectometer diagnostic that generates data and status information. The data distribution system has been implemented using a publishing-subscribing technology that receives data from data generators and redistributes them to client applications. And finally, for monitoring, a client application based on JAVA Web Start technology has been used. There are three interesting results from this project. The first one is the analysis of different aspects (data formats, data frame rate, data resolution, etc) related with remote real-time diagnostic monitoring oriented to long pulse experiments. The second one is the definition and implementation of an architecture, flexible enough to be applied to different types of data generated from other diagnostics, and that fits with remote access requirements. Finally, the third result is a secure system, taking into account internal networks and firewalls aspects of JET, and securing the access from remote users. For this last issue, PAPI technology has been used, enabling access control based on user attributes, enabling mobile users to monitor diagnostics in real-time, and enabling the integration of this service into the EFDA Federation (Castro et al., 2008 ).

Development of Indirect Competitive Immuno-Assay Method Using SPR Detection for Rapid and Highly Sensitive Measurement of Salivary Cortisol Levels

International Nuclear Information System (INIS)

Tahara, Yusuke; Huang, Zhe; Kiritoshi, Tetsuro; Onodera, Takeshi; Toko, Kiyoshi

2014-01-01

The monitoring of salivary cortisol as a key biomarker of an individual’s stress response has been increasingly focused on. This paper describes the development of a novel cortisol immuno-assay method based on an indirect competitive method using a commercially available surface plasmon resonance instrument. The surface of an Au chip was modified with PEG6-COOH aromatic dialkanethiol self-assembled monolayers and hydrocortisone 3-(O-carboxymethyl) oxime (hydrocortisone 3-CMO) as a cortisol analog. A detection limit of 38 ppt range with a measurement range of 10 ppt–100 ppb was accomplished without the incubation of a mixing solution consisting of standard cortisol and an anti-cortisol antibody, and the time for quantification of cortisol concentration was 8 min from the sample injection. We experimentally compared our immuno-assay with a commercialized salivary cortisol enzyme-linked immunosorbent assay (ELISA) kit using human saliva samples. It was found that the results obtained by the cortisol immuno-assay had a good correlation with those obtained by ELISA assay (R = 0.96). Our findings indicate the potential utility of the cortisol immuno-assay for measurements of human salivary cortisol levels.

Development of Indirect Competitive Immuno-Assay Method Using SPR Detection for Rapid and Highly Sensitive Measurement of Salivary Cortisol Levels

Energy Technology Data Exchange (ETDEWEB)

Tahara, Yusuke; Huang, Zhe; Kiritoshi, Tetsuro [Graduate School of Information Science and Electrical Engineering, Kyushu University, Fukuoka (Japan); Onodera, Takeshi [Research and Development Center for Taste and Odor Sensing, Kyushu University, Fukuoka (Japan); Toko, Kiyoshi, E-mail: toko@ed.kyushu-u.ac.jp [Graduate School of Information Science and Electrical Engineering, Kyushu University, Fukuoka (Japan); Research and Development Center for Taste and Odor Sensing, Kyushu University, Fukuoka (Japan)

2014-05-30

The monitoring of salivary cortisol as a key biomarker of an individual’s stress response has been increasingly focused on. This paper describes the development of a novel cortisol immuno-assay method based on an indirect competitive method using a commercially available surface plasmon resonance instrument. The surface of an Au chip was modified with PEG6-COOH aromatic dialkanethiol self-assembled monolayers and hydrocortisone 3-(O-carboxymethyl) oxime (hydrocortisone 3-CMO) as a cortisol analog. A detection limit of 38 ppt range with a measurement range of 10 ppt–100 ppb was accomplished without the incubation of a mixing solution consisting of standard cortisol and an anti-cortisol antibody, and the time for quantification of cortisol concentration was 8 min from the sample injection. We experimentally compared our immuno-assay with a commercialized salivary cortisol enzyme-linked immunosorbent assay (ELISA) kit using human saliva samples. It was found that the results obtained by the cortisol immuno-assay had a good correlation with those obtained by ELISA assay (R = 0.96). Our findings indicate the potential utility of the cortisol immuno-assay for measurements of human salivary cortisol levels.

Effect of chromatographic separation on ASP system interface tension and the countermeasures

Directory of Open Access Journals (Sweden)

Jiawei REN

2016-06-01

Full Text Available Because of the existing chromatographic separation phenomenon, ASP flooding changes original nature of the system. Therefore, in laboratory ultra-low interfacial tension ASP system is preferred for sand packs flow experiment to research on the effect of chromatographic separation on ASP system interface tension. The two parameters of "breakthrough time" and "output difference" are used to describe the degree of chromatographic separation, and the produced fluid interfacial tensions at the outlet end at 120 min is measured. The research shows that there exists chromatographic separation between three chemicals of ASP system, with first polymer breakthrough and finally surfactant breakthrough; there is most serious chromatographic separation between surfactant and polymer, while minimum chromatographic separation between alkali and polymer; chromatographic separation makes ASP interfacial tension increase from 10^-3 magnitude to 10^-2 magnitude, affecting flooding effect of ASP system. Thus, reducing the loss of surfactant in the formation will be the main measure to reduce the degree of chromatographic separation. Using sophorolipid as sacrificial agent to replace part of the surfactant injected into formation before ASP system can effectively reduce the impact of chromatography separation and more effectively improve the ultimate recovery ratio.

Diagnostic validation of selected serological tests for detecting scrub typhus.

Science.gov (United States)

Koraluru, Munegowda; Bairy, Indira; Varma, Muralidhar; Vidyasagar, Sudha

2015-07-01

Clinical diagnosis of scrub typhus is often difficult because the symptoms are very similar to those of other febrile illness such as dengue, leptospirosis, malaria and other viral hemorrhagic fevers. Though better diagnostic tests are available for rickettsial diseases and scrub typhus elsewhere, the Weil-Felix test is still commonly used in India, mainly because microimmunofluorescence assays (M-IFA) were not available in India till recently and relevant staff had insufficient training. The present study was performed to investigate the performance of M-IFA, IgM ELISA, and Weil-Felix test on 546 non-repeated serum samples from subjects suspected of having scrub typhus. One hundred and forty-three of these 546 samples were positive by M-IFA; these cases were also confirmed clinically to have scrub typhus based on their dramatic responses to doxycycline therapy. IgM ELISA was positive in 122 of the 143 M-IFA positive cases and the Weil-Felix test in 96. Though the Weil-Felix test is a heterophile agglutination test, it was found in this study to have good specificity but far too little sensitivity to use as a routine diagnostic test. IgM ELISA can be a good substitute for M-IFA. Incorporation of multiple prototype antigens on M-IFA slides is likely one of the reasons for its superior performance. As newer and better diagnostic assays become available for scrub typhus diagnosis in developed countries, it will be imperative to also use such tests in other endemic countries to prevent over- or under-diagnosis of scrub typhus. © 2015 The Societies and Wiley Publishing Asia Pty Ltd.

Diagnostic Accuracy of Obstructive Airway Adult Test for Diagnosis of Obstructive Sleep Apnea.

Science.gov (United States)

Gasparini, Giulio; Vicini, Claudio; De Benedetto, Michele; Salamanca, Fabrizio; Sorrenti, Giovanni; Romandini, Mario; Bosi, Marcello; Saponaro, Gianmarco; Foresta, Enrico; Laforì, Andreina; Meccariello, Giuseppe; Bianchi, Alessandro; Toraldo, Domenico Maurizio; Campanini, Aldo; Montevecchi, Filippo; Rizzotto, Grazia; Cervelli, Daniele; Moro, Alessandro; Arigliani, Michele; Gobbi, Riccardo; Pelo, Sandro

2015-01-01

The gold standard for the diagnosis of Obstructive Sleep Apnea (OSA) is polysomnography, whose access is however reduced by costs and limited availability, so that additional diagnostic tests are needed. To analyze the diagnostic accuracy of the Obstructive Airway Adult Test (OAAT) compared to polysomnography for the diagnosis of OSA in adult patients. Ninety patients affected by OSA verified with polysomnography (AHI ≥ 5) and ten healthy patients, randomly selected, were included and all were interviewed by one blind examiner with OAAT questions. The Spearman rho, evaluated to measure the correlation between OAAT and polysomnography, was 0.72 (p diagnostic accuracy for the diagnosis of OSA. It has also been shown to be able to discriminate among the different degrees of severity of OSA. Additional large studies aiming to validate this questionnaire as a screening or diagnostic test are needed.

Determination of Seric E immuno-globulins. Comparison of two techniques, radioimmunological and immuno enzymatic. Clinical correlations

International Nuclear Information System (INIS)

Lafosse-Marin, Sylvie.

1977-09-01

Because of the very low seric IgE concentrations their research and analysis are difficult and many techniques of a more or less sophisticated kind have been proposed for this reason. Our aim was to compare two total seric IgE determination methods: one recent, the enzymmuno-Plaque-Pasteur (EPP); the other, most commonly used at present, the Radio-Immuno-Sorbent-Test (RIST). For this we measured total seric IgE in a hundred and one children by the EPP technique and compared our results with those supplied from the same samples by a laboratory using the RIST technique; the results were then correlated with clinical evidence. The technique proposed by the Pasteur Institute to determine total seric IgE is based on radial immunodiffusion sensitized by the use of antibodies labelled with glucose oxydase. This simple technique, easy to use, requires no expensive materials but has two disadvantages: it takes rather a long time and can only measure IgE concentrations of 50 UI/ml or more. The RIST technique is based on competitive fixation, onto anti-IgE-coated Sephadex particles of the IgE under analysis and of a fixed dose of radio-labelled IgE. This second technique, though faster, has the major disadvantage of being practicable in few laboratories because of the heavy equipment needed and the radioactivity used. This study has shown on the whole an equivalence (correlation coefficient 0.95) between the results given by the two techniques: EPP and RIST (the comparison was made between the IgE contents and not their logarithm) [fr

Diagnostic accuracy of physical examination tests of the ankle/foot complex: a systematic review.

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Schwieterman, Braun; Haas, Deniele; Columber, Kirby; Knupp, Darren; Cook, Chad

2013-08-01

Orthopedic special tests of the ankle/foot complex are routinely used during the physical examination process in order to help diagnose ankle/lower leg pathologies. The purpose of this systematic review was to investigate the diagnostic accuracy of ankle/lower leg special tests. A search of the current literature was conducted using PubMed, CINAHL, SPORTDiscus, ProQuest Nursing and Allied Health Sources, Scopus, and Cochrane Library. Studies were eligible if they included the following: 1) a diagnostic clinical test of musculoskeletal pathology in the ankle/foot complex, 2) description of the clinical test or tests, 3) a report of the diagnostic accuracy of the clinical test (e.g. sensitivity and specificity), and 4) an acceptable reference standard for comparison. The quality of included studies was determined by two independent reviewers using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool. Nine diagnostic accuracy studies met the inclusion criteria for this systematic review; analyzing a total of 16 special tests of the ankle/foot complex. After assessment using the QUADAS-2, only one study had low risk of bias and low concerns regarding applicability. Most ankle/lower leg orthopedic special tests are confirmatory in nature and are best utilized at the end of the physical examination. Most of the studies included in this systematic review demonstrate notable biases, which suggest that results and recommendations in this review should be taken as a guide rather than an outright standard. There is need for future research with more stringent study design criteria so that more accurate diagnostic power of ankle/lower leg special tests can be determined. 3a.

A comparison of diagnostic tests for lactose malabsorption - which one is the best?

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Hovde Øistein

2009-10-01

Full Text Available Abstract Background Perceived milk intolerance is a common complaint, and tests for lactose malabsorption (LM are unreliable. This study assesses the agreement between diagnostic tests for LM and describes the diagnostic properties of the tests. Methods Patients above 18 years of age with suspected LM were included. After oral intake of 25 g lactose, a combined test with measurement of serum glucose (s-glucose and hydrogen (H2 and methane (CH4 in expired air was performed and symptoms were recorded. In patients with discrepancies between the results, the combined test was repeated and a gene test for lactose non-persistence was added. The diagnosis of LM was based on an evaluation of all tests. The following tests were compared: Increase in H2, CH4, H2+CH4 and H2+CH4x2 in expired air, increase in s-glucose, and symptoms. The agreement was calculated and the diagnostic properties described. Results Sixty patients were included, seven (12% had LM. The agreement (kappa-values between the methods varied from 0.25 to 0.91. The best test was the lactose breath test with measurement of the increase in H2 + CH4x2 in expired air. With a cut-off level Conclusion The agreement between commonly used methods for the diagnosis of LM was unsatisfactory. A lactose breath test with measurement of H2 + CH4x2 in expired air had the best diagnostic properties.

The role of molecular diagnostic testing in the management of thyroid nodules.

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Moore, Maureen D; Panjwani, Suraj; Gray, Katherine D; Finnerty, Brendan M; Zarnegar, Rasa; Fahey, Thomas J

2017-06-01

Fine needle aspiration (FNA) with cytologic examination remains the standard of care for investigation of thyroid nodules. However, as many as 30% of FNA samples are cytologically indeterminate for malignancy, which confounds clinical management. To reduce the burden of repeat diagnostic testing and unnecessary surgery, there has been extensive investigation into molecular markers that can be detected on FNA specimens to more accurately stratify a patient's risk of malignancy. Areas covered: In this review, the authors discuss recent evidence and progress in molecular markers used in the diagnosis of thyroid cancer highlighting somatic gene alterations, molecular technologies and microRNA analysis. Expert commentary: The goal of molecular markers is to improve diagnostic accuracy and aid clinicians in the preoperative management of thyroid lesions. Modalities such as direct mutation analysis, mRNA gene expression profiling, next-generation sequencing, and miRNA expression profiling have been explored to improve the diagnostic accuracy of thyroid nodule FNA. Although no perfect test has been discovered, molecular diagnostic testing has revolutionized the management of thyroid nodules.

Concordance in diagnostic testing for respiratory pathogens of bighorn sheep

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Walsh, Daniel P.; Cassirer, E. Frances; Bonds, Michael D.; Brown, Daniel R.; Edwards, William H.; Weiser, Glen C.; Drew, Mark L.; Briggs, Robert E.; Fox, Karen A.; Miller, Michael W.; Shanthalingam, Sudarvili; Srikumaran, Subramaniam; Besser, Thomas E.

2016-01-01

Reliable diagnostic tests are essential for disease investigation and management. This is particularly true for diseases of free-ranging wildlife where sampling is logistically difficult precluding retesting. Clinical assays for wildlife diseases frequently vary among laboratories because of lack of appropriate standardized commercial kits. Results of diagnostic testing may also be called into question when investigators report different etiologies for disease outbreaks, despite similar clinical and pathologic findings. To evaluate reliability of diagnostic testing for respiratory pathogens of bighorn sheep (Ovis canadensis), we conducted a series of ring tests across 6 laboratories routinely involved in detection of Mycoplasma ovipneumoniae, Pasteurellaceae, lktA (the Pasteurellaceae gene encoding leukotoxin), and 3 reference laboratories. Consistency of results for replicate samples within laboratories was high (median agreement = 1.0). Agreement between laboratories was high for polymerase chain reaction (PCR) detection of M. ovipneumoniae and culture isolation of Mannheimia spp. and Bibersteinia trehalosi(median agreement = 0.89–0.95, Kappa = 0.65–0.74), and lower for PCR detection of Mannheimiaspp. lktA (median agreement = 0.58, Kappa = 0.12). Most errors on defined status samples were false negatives, suggesting test sensitivity was a greater problem than specificity. However, tests for M. haemolytica and lktA yielded some false positive results. Despite differences in testing protocols, median agreement among laboratories and correct classification of controls for most agents was ≥0.80, meeting or exceeding the standard required by federal proficiency testing programs. This information is valuable for interpreting test results, laboratory quality assessments, and advancing diagnosis of respiratory disease in wild sheep. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Evaluation of pesticide adsorption in gas chromatographic injector and column

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Gevany Paulino de Pinho

2012-01-01

Full Text Available Components in complex matrices can cause variations in chromatographic response during analysis of pesticides by gas chromatography. These variations are related to the competition between analytes and matrix components for adsorption sites in the chromatographic system. The capacity of the pesticides chlorpyrifos and deltamethrin to be adsorbed in the injector and chromatographic column was evaluated by constructing three isotherms and changing the column heating rate to 10 and 30 ºC min-1. By using ANCOVA to compare the slope of calibration graphs, results showed that the higher the injector temperature (310 ºC the lower the pesticide adsorption. Also, deltamethrin influenced the adsorption of chlorpyrifos on the column chromatographic.

Immuno-biosensor for Detection of CD20-Positive Cells Using Surface Plasmon Resonance

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Shanehbandi, Dariush; Majidi, Jafar; Kazemi, Tohid; Baradaran, Behzad; Aghebati-Maleki, Leili; Fathi, Farzaneh; Ezzati Nazhad Dolatabadi, Jafar

2017-01-01

Purpose: Surface plasmon resonance (SPR) sensing confers a real-time assessment of molecular interactions between biomolecules and their ligands. This approach is highly sensitive and reproducible and could be employed to confirm the successful binding of drugs to cell surface targets. The specific affinity of monoclonal antibodies (MAb) for their target antigens is being utilized for development of immuno-sensors and therapeutic agents. CD20 is a surface protein of B lymphocytes which has been widely employed for immuno-targeting of B-cell related disorders. In the present study, binding ability of an anti-CD20 MAb to surface antigens of intact target cells was investigated by SPR technique. Methods: Two distinct strategies were used for immobilization of the anti-CD20 MAb onto gold (Au) chips. MUA (11-mercaptoundecanoic acid) and Staphylococcus aureus protein A (SpA) were the two systems used for this purpose. A suspension of CD20-positive Raji cells was injected in the analyte phase and the resulting interactions were analyzed and compared to those of MOLT-4 cell line as CD20-negative control. Results: Efficient binding of anti-CD20 MAb to the surface antigens of Raji cell line was confirmed by both immobilizing methods, whereas this MAb had not a noticeable affinity to the MOLT-4 cells. Conclusion: According to the outcomes, the investigated MAb had acceptable affinity and specificity to the target antigens on the cell surface and could be utilized for immuno-detection of CD20-positive intact cells by SPR method. PMID:28761820

[Clinical investigation of basophil activation test as a complementary test for house dust mite allergen].

Science.gov (United States)

Ren, H L; Li, J D; Miao, Y H; Xu, T

2018-03-01

Objective: To investigate the clinical application of glass micro fiber basophil activation test (BAT) used as a complementary test for house dust mite allergen. Method: Forty patients with clinical diagnosed allergic rhinitis was test by three methods for house dust mite allergen, skin prick test(SPT),Immuno CAP sIgE, and BAT in vitro. The sensitivity and specificity of glass micro fiber were accessed, and the consistency between BAT, SPT, and Immuno sIgE was analyzed. As in vivo provocation was not performed, gold standard is regarded as the combination of medical history and positive reports of SPT and/or ImmunoCAP sIgE test. Result: Twentythree patients are diagnosed as house dust mite allergic rhinitis by gold standard. The sensitivity and specificity of glass micro fiber BAT were 60.9% and 88.2%, the sensitivity of SPT and sIgE was 87.0% and sIgE 73.9%. The correlation rates between BAT with SPT is 0.67( P house dust mite allergic rhinitis, BAT have a good consistency with SPT and sIgE, while as it has only moderate consistency with "gold standard", further studies are needed to prove its clinical significance. Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.

Comparison of immunoglobulin E measurements on IMMULITE and ImmunoCAP in samples consisting of allergen-specific mouse-human chimeric monoclonal antibodies towards allergen extracts and four recombinant allergens

DEFF Research Database (Denmark)

Szecsi, Pal B; Stender, Steen

2013-01-01

Specific immunoglobulin E (IgE) antibody in vitro tests are performed on enzyme immunoassay systems. Poor agreement among systems has been reported and comparisons have been made exclusively with allergen extracts - not with recombinant allergens. Here we compare the ImmunoCAP and the IMMULITE sy...

The effect of resuscitation strategy on the longitudinal immuno-inflammatory response to blunt trauma

DEFF Research Database (Denmark)

Bonde, Alexander; Nordestgaard, Ask Tybjærg; Kirial, Rasmus

2017-01-01

INTRODUCTION: Resuscitation strategies following blunt trauma have been linked to immuno-inflammatory complications leading to systemic inflammatory syndrome (SIRS), sepsis and multiple organ failure (MOF). The effect of resuscitation strategy on longitudinal inflammation marker trajectories is...

A systematic review of the diagnostic performance of orthopedic physical examination tests of the hip.

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Rahman, Labib Ataur; Adie, Sam; Naylor, Justine Maree; Mittal, Rajat; So, Sarah; Harris, Ian Andrew

2013-08-30

Previous reviews of the diagnostic performances of physical tests of the hip in orthopedics have drawn limited conclusions because of the low to moderate quality of primary studies published in the literature. This systematic review aims to build on these reviews by assessing a broad range of hip pathologies, and employing a more selective approach to the inclusion of studies in order to accurately gauge diagnostic performance for the purposes of making recommendations for clinical practice and future research. It specifically identifies tests which demonstrate strong and moderate diagnostic performance. A systematic search of Medline, Embase, Embase Classic and CINAHL was conducted to identify studies of hip tests. Our selection criteria included an analysis of internal and external validity. We reported diagnostic performance in terms of sensitivity, specificity, predictive values and likelihood ratios. Likelihood ratios were used to identify tests with strong and moderate diagnostic utility. Only a small proportion of tests reported in the literature have been assessed in methodologically valid primary studies. 16 studies were included in our review, producing 56 independent test-pathology combinations. Two tests demonstrated strong clinical utility, the patellar-pubic percussion test for excluding radiologically occult hip fractures (negative LR 0.05, 95% Confidence Interval [CI] 0.03-0.08) and the hip abduction sign for diagnosing sarcoglycanopathies in patients with known muscular dystrophies (positive LR 34.29, 95% CI 10.97-122.30). Fifteen tests demonstrated moderate diagnostic utility for diagnosing and/or excluding hip fractures, symptomatic osteoarthritis and loosening of components post-total hip arthroplasty. We have identified a number of tests demonstrating strong and moderate diagnostic performance. These findings must be viewed with caution as there are concerns over the methodological quality of the primary studies from which we have extracted our

Chromatographic Determination of Toluene and its Metabolites in Urine for Toluene Exposure - A Review

International Nuclear Information System (INIS)

Mohamad Raizul Zinalibdin; Abdul Rahim Yacob; Mohd Marsin Sanagi

2016-01-01

The determinations of toluene and their metabolites in biological samples such as urine and blood allow the estimation of the degree of exposure to this chemical. Chromatographic methods and preliminary methods are now universally employed for this purpose. Preliminary color test methods are well established for qualitative determination of toluene and its metabolites. Mobile test kits using color test methods are a vast tool for screening urine samples but chromatographic methods are still needed for confirmation and quantitative analysis. Gas chromatography (GC) methods are well-adapted for the determination of toluene metabolite in urine, but these methods often require several pretreatment steps. Meanwhile, high performance liquid chromatography (HPLC) is becoming a powerful tool for the accurate and easy determination of toluene metabolites considering its decisive advantages for routine monitoring. Furthermore, recent development in HPLC could widen the usefulness of this method to solve the most complex analytical problems that could be encountered during the measurement. (author)

Sensitization to cereals and peanut evidenced by skin prick test and specific IgE in food-tolerant, grass pollen allergic patients

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Martens Maria

2011-12-01

Full Text Available Abstract Background The botanical relation between grass and cereal grains may be relevant when diagnosing food allergy to cereals. The aim was to investigate the diagnostic specificity of skin prick test (SPT and specific immunoglobulin E (sIgE tests to cereals and peanut in grass pollen allergic subjects without history of, and clinically reactions to foods botanically related to grass. Methods 70 subjects (41 females; mean age 32 years and 20 healthy controls (13 females; mean age 24 years were tested by open food challenge (OFC with cereals and peanut. SPT and sIgE both with Immulite® (Siemens and ImmunoCAP® (Phadia to grass and birch pollen, cereals, peanut and bromelain were performed. Results Of the 65 OFC-negative subjects 29-46% (SPT, depending on cut-off, 20% (Immulite and 38% (ImmunoCAP had positive results to one or more of the foods tested. Controls were negative in all tests. Cross-reactive carbohydrate determinants (CCD as evidenced by reaction to bromelain could explain only a minority of the measured IgE-sensitizations. Conclusion Grass pollen allergic patients with documented food tolerance to cereals and peanut may express significant sensitization. False-positive cereal or peanut allergy diagnoses may be a quantitatively important problem both in routine clinical work and epidemiological studies.

Quality of information accompanying on-line marketing of home diagnostic tests.

Science.gov (United States)

Datta, Adrija K; Selman, Tara J; Kwok, Tony; Tang, Teresa; Khan, Khalid S

2008-01-01

To assess the quality of information provided to consumers by websites marketing medical home diagnostic tests. A cross-sectional analysis of a database developed from searching targeted websites. Data sources were websites written in English which marketed medical home diagnostic tests. A meta-search engine was used to identify the first 20 citations for each type of home diagnostic medical test. Relevant websites limited to those written in English were reviewed independently and in triplicate, with disputes resolved by two further reviewers. Information on the quality of these sites was extracted using a pre-piloted performer. 168 websites were suitable for inclusion in the review. The quality of these sites showed marked variation. Only 24 of 168 (14.2%) complied with at least three-quarters of the quality items and just over half (95 of 168, 56.5%) reported official approval or certification of the test. Information on accuracy of the test marketed was reported by 87 of 168 (51.7%) websites, with 15 of 168 (8.9%) providing a scientific reference. Instructions for use of the product were found in 97 of 168 (57.9%). However, the course of action to be taken after obtaining the test result was stated in only 63 of 168 (37.5%) for a positive result and 43 of 168 (25.5%) for a negative result. The quality of information posted on commercial websites marketing home tests online is unsatisfactory and potentially misleading for consumers.

Evidence Based Medicine; Positive and Negative Likelihood Ratios of Diagnostic Tests

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Alireza Baratloo

2015-10-01

Full Text Available In the previous two parts of educational manuscript series in Emergency, we explained some screening characteristics of diagnostic tests including accuracy, sensitivity, specificity, and positive and negative predictive values. In the 3rd  part we aimed to explain positive and negative likelihood ratio (LR as one of the most reliable performance measures of a diagnostic test. To better understand this characteristic of a test, it is first necessary to fully understand the concept of sensitivity and specificity. So we strongly advise you to review the 1st part of this series again. In short, the likelihood ratios are about the percentage of people with and without a disease but having the same test result. The prevalence of a disease can directly influence screening characteristics of a diagnostic test, especially its sensitivity and specificity. Trying to eliminate this effect, LR was developed. Pre-test probability of a disease multiplied by positive or negative LR can estimate post-test probability. Therefore, LR is the most important characteristic of a test to rule out or rule in a diagnosis. A positive likelihood ratio > 1 means higher probability of the disease to be present in a patient with a positive test. The further from 1, either higher or lower, the stronger the evidence to rule in or rule out the disease, respectively. It is obvious that tests with LR close to one are less practical. On the other hand, LR further from one will have more value for application in medicine. Usually tests with 0.1 < LR > 10 are considered suitable for implication in routine practice.

The dilemma of diagnostic testing for Prader-Willi syndrome

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Hung, Dorothy

2017-01-01

Although Prader-Willi syndrome (PWS) is a well-described clinical dysmorphic syndrome, DNA testing is required for a definitive diagnosis. A definitive diagnosis can be made in approximately 99% of cases using DNA testing; there are a number of DNA tests that can be used for this purpose, although there is no set standard algorithm of testing. The dilemma arises because of the complex genetic mechanisms at the basis of PWS, which need to be elucidated. To establish the molecular mechanism with a complete work up, involves at least 2 tests. Here we discuss the commonly used tests currently available and suggest a cost—effective approach to diagnostic testing. PMID:28164030

ImmunoGrid, an integrative environment for large-scale simulation of the immune system for vaccine discovery, design and optimization

DEFF Research Database (Denmark)

Pappalardo, F.; Halling-Brown, M. D.; Rapin, Nicolas

2009-01-01

conceptual models of the immune system, models of antigen processing and presentation, system-level models of the immune system, Grid computing, and database technology to facilitate discovery, formulation and optimization of vaccines. ImmunoGrid modules share common conceptual models and ontologies......Vaccine research is a combinatorial science requiring computational analysis of vaccine components, formulations and optimization. We have developed a framework that combines computational tools for the study of immune function and vaccine development. This framework, named ImmunoGrid combines...

Immuno phenotype of blood lymphocytes in radiation-associated Hodgkin's disease

International Nuclear Information System (INIS)

Butenko, A.K.

2000-01-01

Immuno phenotype of peripheral blood lymphocytes has been studied in Hodgkin's disease including patients exposed to radionuclides of the characteristic Chernobyl pattern. The group of patients under study has been characterized by decreasing T- and NK-cell immunity, such a decrease being more pronounced in radiation-associated Hodgkin's lymphoma. The data obtained as well as the evidence of Epstein-Barr virus activation could explain the aggressiveness of the disease in such patients and the difficulties in their treatment

Een onderzoek over de waarde van de Schultz-Dale techniek in de immuno-pathologie

NARCIS (Netherlands)

Jansz, Anton

1960-01-01

Dit proefschrift geeft in hoofdstuk I een overzicht over problemen in de immuno-pathologie. waarbij vooral aandacht wordt geschonken aan de auto-immunologische ziekteprocessen. Een beter inzicht hierin kan verkregen worden door dierexperimenteel en door serologisch onderzoek. Het laatste vooral

Competitive adsorption of albumin and monoclonal immuno upsilon globulin molecules on polystyrene surfaces

NARCIS (Netherlands)

Elgersma, F.

1990-01-01

The subject of this thesis is proteins at interfaces. The main purpose of the work was to acquire more insight into the mechanism of adsorption of Bovine Serum Albumin (BSA) and monoclonal Immuno gamma Globulins (IgG's). both individually and in competition. Another aim was to achieve

The Evaluation of Diagnostic Tests for Sexually Transmitted Infections

Directory of Open Access Journals (Sweden)

Max A Chernesky

2005-01-01

Full Text Available Diagnostic tests should receive method- and use-effectiveness evaluations. Method-effectiveness evaluations determine sensitivity, specificity and predictive values for new tests. Use-effectiveness evaluations determine how practical or convenient a new test will be in a specific setting and may not be performed in a formal way in North American laboratories. To perform a clinical method evaluation of diagnostic tests, a good relationship between laboratory and clinical personnel is essential. Studies are usually conducted separately on populations of men and women, and should include sampling from different prevalence groups. Test performance comparisons may be made on a single specimen type or on more than one specimen from the same patient, which allows for the expansion of a reference standard and includes the ability of a particular assay, performed on a specimen type to diagnose an infected individual. The following components of the evaluation should be standardized and carefully followed: specimen identification; collection; transportation; processing; quality control; reading; proficiency testing; confirmatory testing; discordant analysis -- sensitivity, specificity and predictive value calculations; and record keeping. Methods are available to determine whether sample results are true or false positives or negatives. Use-effectiveness evaluations might determine the stability or durability of supplies and equipment; the logistics of shipping, receiving and storing supplies; the clarity and completeness of test instructions; the time and effort required to process and read results; the subjectivity factors in interpretation and reporting; and the costs. These determinations are usually more apparent for commercial assays than for homemade tests.

Diagnostic Tests for Entering and Departing Undergraduate Students

Science.gov (United States)

Waltham, Chris; Kotlicki, A.

2006-12-01

A diagnostic test administered at the start of a class should test basic concepts which are recognized as course prerequisites. The questions should not be over-packaged: e.g. students should be required to create models, rather than this being done for them each time. Students should be allowed great latitude in their answers, so we can discover what they are thinking. When administered at the end of a class the goals should be similar: testing concepts taught in the class itself and the retention of necessary concepts from previous classes. Great care has to be taken to avoid teaching to the test. In assessing an entire program, for example an undergraduate majors degree in physics, then one looks for very general skills and knowledge not specific to any one course. The purpose of an undergraduate degree in physics (or indeed any science) is to equip the students with a set of problem-solving skills and basic knowledge which can be applied in a large variety of workplace settings and to allow that student to contribute to civic society as a science-literate person. The creator of any diagnostic test should always have these big goals in mind. We have developed a set of questions which we think fulfill these criteria, yet are not specific to any particular level of science education. They have been administered to students in secondary schools across Canada, incoming first-year science students and final-year physics students at the University of British Columbia. The results will be presented.

Evaluation of a new rapid lateral flow chromatography test for the diagnosis of Helicobacter Pylori

International Nuclear Information System (INIS)

Kaklikkaya, N.; Dinc, U.; Dabanca, Pinar A.; Aydin, F.; Erturk, M.; Akdogan, Remzi A.; Ozgur, O.; Uzun, Dogan Y.; Gungor, E.; Arslan, M.; Cobanoglu, U.

2006-01-01

The rapid, simple and non-invasive diagnosis of Helicobacter pylori (H. pylori) infection is important in implementing chemotherapy in appropriate manner, and in assessing persistent H. pylori infection after eradication therapy. The Immuno Card STAT HpSA kit (Meridian Bioscience, Europe) is a lateral flow chromatography test which utilizes a monoclonal anti-H. pylori antibody. In this study, we investigated the usefulness of the ImmunoCard STAT HpSA test before and after eradication therapy on patients referred to undergo upper gastrointestinal endoscopy. Sixty-five consecutive patients who were referred to undergo upper gastrointestinal endoscopy at the Department of Gastroenterology, Karadeniz Technical University Medical School, Turkey between February and August 2005 were included in this study. The ImmunoCard STAT HpSA was compared with 4 invasive tests (histology, gram staining, rapid urease test, and culture). The reference method was defined as positive when 2 of the 4 invasive tests were positive. A negative H. pylori status was considered when all 4 tests present concordant negative results. Overall, the ImmunoCard STAT HpSA test had 77.8% sensitivity, 79.3% specificity, 82.4% positive predictive value (PPV) and 74.2% negative predictive value (NPV) in all patients. With regard to pre-treatment values, the sensitivity was 70.6%, specificity 70.6%, PPV 100% and NPV 100% while on post-treatment group the sensitivity was 84.2%, specificity 64.7%, PPV 72.7% and NPV 78.6%. Our results indicate that the ImmunoCard STAT HpSA test is a rapid, simple, and helpful procedure not only to determine H. pylori infection but also to assess the success of eradication therapy. (author)

Beyond the 2×2 -contingency table: a primer on entropies and mutual information in various scenarios involving m diagnostic categories and n categories of diagnostic tests.

Science.gov (United States)

Reibnegger, Gilbert

2013-10-21

Usual evaluation tools for diagnostic tests such as, sensitivity/specificity and ROC analyses, are designed for the discrimination between two diagnostic categories, using dichotomous test results. Information theoretical quantities such as mutual information allow in depth-analysis of more complex discrimination problems, including continuous test results, but are rarely used in clinical chemistry. This paper provides a primer on useful information theoretical concepts with a strong focus on typical diagnostic scenarios. Information theoretical concepts are shortly explained. Mathematica CDF documents are provided which compute entropies and mutual information as function of pretest probabilities and the distribution of test results among the categories, and allow interactive exploration of the behavior of these quantities in comparison with more conventional diagnostic measures. Using data from a previously published study, the application of information theory to practical diagnostic problems involving up to 4×4 -contingency tables is demonstrated. Information theoretical concepts are particularly useful for diagnostic problems requiring more than the usual binary classification. Quantitative test results can be properly analyzed, and in contrast to popular concepts such as ROC analysis, the effects of variations of pre-test probabilities of the diagnostic categories can be explicitly taken into account. © 2013 Elsevier B.V. All rights reserved.

Identification student’s misconception of heat and temperature using three-tier diagnostic test

Science.gov (United States)

Suliyanah; Putri, H. N. P. A.; Rohmawati, L.

2018-03-01

The objective of this research is to develop a Three-Tier Diagnostic Test (TTDT) to identify the student's misconception of heat and temperature. Stages of development include: analysis, planning, design, development, evaluation and revise. The results of this study show that (1) the quality of the three-tier type diagnostic test instrument developed has been expressed well with the following details: (a) Internal validity of 88.19% belonging to the valid category. (b) External validity of empirical construct validity test using Pearson Product Moment obtained 0.43 is classified and result of empirical construct validity test obtained false positives 6.1% and false negatives 5.9% then the instrument was valid. (c) Test reliability by using Cronbach’s Alpha of 0.98 which means acceptable. (d) The 80% difficulty level test is quite difficult. (2) Student misconceptions on the temperature of heat and displacement materials based on the II test the highest (84%), the lowest (21%), and the non-misconceptions (7%). (3) The highest cause of misconception among students is associative thinking (22%) and the lowest is caused by incomplete or incomplete reasoning (11%). Three-Tier Diagnostic Test (TTDT) could identify the student's misconception of heat and temperature.

Quality of information accompanying on-line marketing of home diagnostic tests

Science.gov (United States)

Datta, Adrija K; Selman, Tara J; Kwok, Tony; Tang, Teresa; Khan, Khalid S

2008-01-01

Objective To assess the quality of information provided to consumers by websites marketing medical home diagnostic tests. Design A cross-sectional analysis of a database developed from searching targeted websites. Setting Data sources were websites written in English which marketed medical home diagnostic tests. Main outcome measures A meta-search engine was used to identify the first 20 citations for each type of home diagnostic medical test. Relevant websites limited to those written in English were reviewed independently and in triplicate, with disputes resolved by two further reviewers. Information on the quality of these sites was extracted using a pre-piloted performer. Results 168 websites were suitable for inclusion in the review. The quality of these sites showed marked variation. Only 24 of 168 (14.2%) complied with at least three-quarters of the quality items and just over half (95 of 168, 56.5%) reported official approval or certification of the test. Information on accuracy of the test marketed was reported by 87 of 168 (51.7%) websites, with 15 of 168 (8.9%) providing a scientific reference. Instructions for use of the product were found in 97 of 168 (57.9%). However, the course of action to be taken after obtaining the test result was stated in only 63 of 168 (37.5%) for a positive result and 43 of 168 (25.5%) for a negative result. Conclusions The quality of information posted on commercial websites marketing home tests online is unsatisfactory and potentially misleading for consumers. PMID:18263912

Diagnostic significance of haematological testing in patients presenting at the Emergency Department

Directory of Open Access Journals (Sweden)

Giuseppe Lippi

2012-03-01

Full Text Available The use of simple and economic tests to rule out diseases of sufficient clinical severity is appealing in emergency department (ED, since it would be effective for contrasting ED overcrowding and decreasing healthcare costs. The aim of this study was to assess the diagnostic performance of simple and economic haematological testing in a large sample of adult patients presenting at the ED of the Academic Hospital of Parma during the year 2010 with the five most frequent acute pathologies (i.e., acute myocardial infarction, renal colic, pneumonia, trauma and pancreatitis. Both leukocyte count and hemoglobin showed a good diagnostic performance (Area Under the Curve [AUC] of 0.85 for leukocyte count and 0.76 for hemoglobin; both p < 0.01. Although the platelet count was significantly increased in all patients groups except pancreatitis, the diagnostic performance did not achieve statistical significance (AUC 0.53; p = 0.07. We also observed an increased RDW in all groups, except in those with trauma and the diagnostic performance was acceptable (AUC 0.705; p < 0.01. The mean platelet volume (MPV was consistently lower in all patients groups and also characterized by an efficient diagnostic performance (AUC 0.76; p < 0.01. This evidence led us to design an arbitrary formula, whereby MPV and hemoglobin were multiplied, and further divided by the leukocyte count, obtaining a remarkable AUC (0.91; p < 0.01. We conclude that simple, rapid and cheap hematological tests might provide relevant clinical information for decision making to busy emergency physicians, and the their combination into an arbitrary formula might further increase the specific diagnostic potential of each of them.

Auditory Automotive Mechanics Diagnostic Achievement Test. Center Technical Paper No. 2.

Science.gov (United States)

Swanson, Richard Arthur

The Auditory Automotive Mechanics Diagnostic Achievement Test assesses an automobile mechanic's ability to determine mechanical faults from auditory cues alone. The 44-item test and its instructions are recorded on magnetic tape; answer choices are presented on tape, and are also written in the printed test booklets. The norming and validity…

Decision making about healthcare-related tests and diagnostic test strategies. Paper 2: a review of methodological and practical challenges.

Science.gov (United States)

Mustafa, Reem A; Wiercioch, Wojtek; Cheung, Adrienne; Prediger, Barbara; Brozek, Jan; Bossuyt, Patrick; Garg, Amit X; Lelgemann, Monika; Büehler, Diedrich; Schünemann, Holger J

2017-12-01

In this first of a series of five articles, we provide an overview of how and why healthcare-related tests and diagnostic strategies are currently applied. We also describe how our findings can be integrated with existing frameworks for making decisions that guide the use of healthcare-related tests and diagnostic strategies. We searched MEDLINE, references of identified articles, chapters in relevant textbooks, and identified articles citing classic literature on this topic. We provide updated frameworks for the potential roles and applications of tests with suggested definitions and practical examples. We also discuss study designs that are commonly used to assess tests' performance and the effects of tests on people's health. These designs include diagnostic randomized controlled trials and retrospective validation. We describe the utility of these and other currently suggested designs, which questions they can answer and which ones they cannot. In addition, we summarize the challenges unique to decision-making resulting from the use of tests. This overview highlights current challenges in the application of tests in decision-making in healthcare, provides clarifications, and informs the proposed solutions. Copyright © 2017 Elsevier Inc. All rights reserved.

Performance Evaluation of Commercial Dengue Diagnostic Tests for Early Detection of Dengue in Clinical Samples

Directory of Open Access Journals (Sweden)

Tuan Nur Akmalina Mat Jusoh

2017-01-01

Full Text Available The shattering rise in dengue virus infections globally has created a need for an accurate and validated rapid diagnostic test for this virus. Rapid diagnostic test (RDT and reverse transcription-polymerase chain reaction (RT-PCR diagnostic detection are useful tools for diagnosis of early dengue infection. We prospectively evaluated the diagnostic performance of nonstructural 1 (NS1 RDT and real-time RT-PCR diagnostic kits in 86 patient serum samples. Thirty-six samples were positive for dengue NS1 antigen while the remaining 50 were negative when tested with enzyme-linked immunosorbent assay (ELISA. Commercially available RDTs for NS1 detection, RTK ProDetect™, and SD Bioline showed high sensitivity of 94% and 89%, respectively, compared with ELISA. GenoAmp® Trioplex Real-Time RT-PCR and RealStar® Dengue RT-PCR tests presented a comparable kappa agreement with 0.722. The result obtained from GenoAmp® Real-Time RT-PCR Dengue test showed that 14 samples harbored dengue virus type 1 (DENV-1, 8 samples harbored DENV-2, 2 samples harbored DENV-3, and 1 sample harbored DENV-4. 1 sample had a double infection with DENV-1 and DENV-2. The NS1 RDTs and real-time RT-PCR tests were found to be a useful diagnostic for early and rapid diagnosis of acute dengue and an excellent surveillance tool in our battle against dengue.

Comparison the diagnostic value of serological and molecular methods for screening and detecting Chlamydia trachomatis in semen of infertile men: A cross-sectional study

Directory of Open Access Journals (Sweden)

Amin Khoshakhlagh

2017-12-01

Full Text Available Background: Chlamydia trachomatis (CT with damaging effects on sperm quality parameters can often cause infertility in men. Objective: The main objective of this study was to determine the diagnostic value of polymerase chain reaction (PCR and enzyme linked immuno sorbent assay (ELISA for screening and detecting CT in semen samples of infertile men. Materials and Methods: In this cross-sectional study, 465 men referring to the clinical laboratory of Royan Institute were chosen for primary screening and detection of the presence of CT. 93 samples were normozoospermia with normal sperm parameters i.e. sperm number, motility and morphology (Asymptomatic and 372 had abnormal sperm parameters (Symptomatic in semen analysis. ELISA test was performed as the screening test. Samples with optical density (OD >0.200 were selected as the case and asymptomatic samples with OD 0.400 as the ELISA positive, the diagnostic value of CT-ELISA positive in symptomatic and asymptomatic infertile patients were 0.019 (7 of 372 and 0.021 (2 of 93, respectively. There was no relationship between the presence of CT infection and different sperm abnormalities. Conclusion: The anti-CT IgA ELISA test may be introduced as an appropriate tool for screening purpose in the seminal plasma to select suspicious samples for PCR confirmatory tests.

Diagnostic and laboratory test ordering in Northern Portuguese Primary Health Care: a cross-sectional study

Science.gov (United States)

Sá, Luísa; Teixeira, Andreia Sofia Costa; Tavares, Fernando; Costa-Santos, Cristina; Couto, Luciana; Costa-Pereira, Altamiro; Hespanhol, Alberto Pinto; Santos, Paulo

2017-01-01

Objectives To characterise the test ordering pattern in Northern Portugal and to investigate the influence of context-related factors, analysing the test ordered at the level of geographical groups of family physicians and at the level of different healthcare organisations. Design Cross-sectional study. Setting Northern Primary Health Care, Portugal. Participants Records about diagnostic and laboratory tests ordered from 2035 family physicians working at the Northern Regional Health Administration, who served approximately 3.5 million Portuguese patients, in 2014. Outcomes To determine the 20 most ordered diagnostic and laboratory tests in the Northern Regional Health Administration; to identify the presence and extent of variations in the 20 most ordered diagnostic and laboratory tests between the Groups of Primary Care Centres and between health units; and to study factors that may explain these variations. Results The 20 most ordered diagnostic and laboratory tests almost entirely comprise laboratory tests and account for 70.9% of the total tests requested. We can trace a major pattern of test ordering for haemogram, glucose, lipid profile, creatinine and urinalysis. There was a significant difference (P<0.001) in test orders for all tests between Groups of Primary Care Centres and for all tests, except glycated haemoglobin (P=0.06), between health units. Generally, the Personalised Healthcare Units ordered more than Family Health Units. Conclusions The results from this study show that the most commonly ordered tests in Portugal are laboratory tests, that there is a tendency for overtesting and that there is a large variability in diagnostic and laboratory test ordering in different geographical and organisational Portuguese primary care practices, suggesting that there may be considerable potential for the rationalisation of test ordering. The existence of Family Health Units seems to be a strong determinant in decreasing test ordering by Portuguese family

The impact of communication barriers on diagnostic confidence and ancillary testing in the emergency department.

Science.gov (United States)

Garra, Gregory; Albino, Hiram; Chapman, Heather; Singer, Adam J; Thode, Henry C

2010-06-01

Communication barriers (CBs) compromise the diagnostic power of the medical interview and may result in increased reliance on diagnostic tests or incorrect test ordering. The prevalence and degree to which these barriers affect diagnosis, testing, and treatment are unknown. To quantify and characterize CBs encountered in the Emergency Department (ED), and assess the effect of CBs on initial diagnosis and perceived reliance on ancillary testing. This was a prospective survey completed by emergency physicians after initial adult patient encounters. CB severity, diagnostic confidence, and reliance on ancillary testing were quantified on a 100-mm Visual Analog Scale (VAS) from least (0) to most (100). Data were collected on 417 ED patient encounters. CBs were reported in 46%; with a mean severity of 50 mm on a 100-mm VAS with endpoints of "perfect communication and "no communication." Language was the most commonly reported form of CB (28%). More than one CB was identified in 6%. The 100-mm VAS rating of diagnostic confidence was lower in patients with perceived CBs (64 mm) vs. those without CBs (80 mm), p Communication barriers in our ED setting were common, and resulted in lower diagnostic confidence and increased perception that ancillary tests are needed to narrow the diagnosis. Copyright 2010 Elsevier Inc. All rights reserved.

Mirror fusion test facility plasma diagnostics system

International Nuclear Information System (INIS)

Thomas, S.R. Jr.; Coffield, F.E.; Davis, G.E.; Felker, B.

1979-01-01

During the past 25 years, experiments with several magnetic mirror machines were performed as part of the Magnetic Fusion Energy (MFE) Program at LLL. The latest MFE experiment, the Mirror Fusion Test Facility (MFTF), builds on the advances of earlier machines in initiating, stabilizing, heating, and sustaining plasmas formed with deuterium. The goals of this machine are to increase ion and electron temperatures and show a corresponding increase in containment time, to test theoretical scaling laws of plasma instabilities with increased physical dimensions, and to sustain high-beta plasmas for times that are long compared to the energy containment time. This paper describes the diagnostic system being developed to characterize these plasma parameters

Multiple chromatographic fingerprinting and its application to the quality control of herbal medicines

International Nuclear Information System (INIS)

Fan Xiaohui; Cheng Yiyu; Ye Zhengliang; Lin Ruichao; Qian Zhongzhi

2006-01-01

Recently, chromatographic fingerprinting has become one of the most powerful approaches to quality control of herbal medicines. However, the performance of reported chromatographic fingerprinting constructed by single chromatogram sometimes turns out to be inadequate for complex herbal medicines, such as multi-herb botanical drug products. In this study, multiple chromatographic fingerprinting, which consists of more than one chromatographic fingerprint and represents the whole characteristics of chemical constitutions of the complex medicine, is proposed as a potential strategy in this complicated case. As a typical example, a binary chromatographic fingerprinting of 'Danshen Dropping Pill' (DSDP), the best-sold traditional Chinese medicine in China, was developed. First, two HPLC fingerprints that, respectively, represent chemical characteristics of depsides and saponins of DSDP were developed, which were used to construct binary chromatographic fingerprints of DSDP. Moreover, the authentication and validation of the binary fingerprints were performed. Then, a data-level information fusion method was employed to capture the chemical information encoded in two chromatographic fingerprints. Based on the fusion results, the lot-to-lot consistency and frauds can be determined either using similarity measure or by chemometrics approach. The application of binary chromatographic fingerprinting to consistency assessment and frauds detection of DSDP clearly demonstrated that the proposed method was a powerful approach to quality control of complex herbal medicines

Development of a molecular diagnostic test for Retinitis Pigmentosa in the Japanese population.

Science.gov (United States)

Maeda, Akiko; Yoshida, Akiko; Kawai, Kanako; Arai, Yuki; Akiba, Ryutaro; Inaba, Akira; Takagi, Seiji; Fujiki, Ryoji; Hirami, Yasuhiko; Kurimoto, Yasuo; Ohara, Osamu; Takahashi, Masayo

2018-05-21

Retinitis Pigmentosa (RP) is the most common form of inherited retinal dystrophy caused by different genetic variants. More than 60 causative genes have been identified to date. The establishment of cost-effective molecular diagnostic tests with high sensitivity and specificity can be beneficial for patients and clinicians. Here, we developed a clinical diagnostic test for RP in the Japanese population. Evaluation of diagnostic technology, Prospective, Clinical and experimental study. A panel of 39 genes reported to cause RP in Japanese patients was established. Next generation sequence (NGS) technology was applied for the analyses of 94 probands with RP and RP-related diseases. After interpretation of detected genetic variants, molecular diagnosis based on a study of the genetic variants and a clinical phenotype was made by a multidisciplinary team including clinicians, researchers and genetic counselors. NGS analyses found 14,343 variants from 94 probands. Among them, 189 variants in 83 probands (88.3% of all cases) were selected as pathogenic variants and 64 probands (68.1%) have variants which can cause diseases. After the deliberation of these 64 cases, molecular diagnosis was made in 43 probands (45.7%). The final molecular diagnostic rate with the current system combining supplemental Sanger sequencing was 47.9% (45 of 94 cases). The RP panel provides the significant advantage of detecting genetic variants with a high molecular diagnostic rate. This type of race-specific high-throughput genotyping allows us to conduct a cost-effective and clinically useful genetic diagnostic test.

Miniaturized chromatographic radiochemical procedure for 131I - MIBG

International Nuclear Information System (INIS)

Barboza, M.F. de; Pereira, N.S. de; Colturato, M.T.; Silva, C.P.G. da.

1989-12-01

Different solvents were used in paper chromatographic methods to obtain the best system in routine radiochemical control for 131 I-MIBG produced at IPEN-CNEN/SP. The dates were compared with those obtained with eletrophoresis method in buffer acetate, pH=4.5, 350V, during 40 minutes. The stability of the labeled compound store under 4 0 C was studied during 15 days. Miniaturized chromatographic procedures were established using Whatman 3MM (8x1cm) and n-butanol-:acetic acid: water (S:2:1) as a solvent. the Rf values were: 0.3 (I - ) and 1.0 (MIBG). The radiochemical purity was 99.3 and 99.2% (first day) obtained with eletrophoresis and miniaturized chromatographic procedures, respectively and, 84.7% after 15 days of its preparation. It is a rapid, practical and reproductive method. (author) [pt

Inventions leading to the development of the diagnostic test kit industry--from the modern pregnancy test to the sandwich assays.

Science.gov (United States)

Wide, Leif

2005-01-01

The universities are encouraged by the government nowadays to stimulate innovations and also to provide the proper machinery for assisting the protection and commercialisation of innovations. A better understanding of the innovation process may help to create an atmosphere suitable for inventions at the university. Examples can be taken from successful innovations previously made at the university. During the 1960's I made a series of inventions, which ultimately led to the development of the diagnostic test kit industry. The first, which I made as an undergraduate, was a simple and reliable test kit for diagnosis of pregnancy. This was followed by the solid phase radioimmunoassay and a solid phase assay for vitamin B12; next, the dual specific non-competitive sandwich assay and the in-vitro test for diagnosis of allergy, called RAST (Radioallergosorbent test). Organon in Holland with the pregnancy test kit, and Pharmacia in Sweden with test kits for radioimmunoassay, became pioneers among the diagnostic test kit industries. Pharmacia Diagnostics later became one of the leading diagnostic test kit companies in the world and has continued to be so in the field of allergy diagnosis. Each one of these inventions started with a few unique observations leading to a technical development. The pregnancy test as well as the allergy test emerged from the development of assay methods with unique qualities with the subsequent search for appropriate applications. The foreseeing of a commercial value on a future market was a very important step. This was followed by the search for a suitable industry interested to exploit the invention with its new business opportunity i.e. apply for a patent, produce and market the products, which in my case consisted of the necessary reagents and equipments for particular diagnostic tests. Finally, an agreement had to be settled between the entrepreneur and the inventors. This report describes these inventions and particularly discusses some

Pre-examination factors affecting molecular diagnostic test results and interpretation: A case-based approach.

Science.gov (United States)

Payne, Deborah A; Baluchova, Katarina; Peoc'h, Katell H; van Schaik, Ron H N; Chan, K C Allen; Maekawa, Masato; Mamotte, Cyril; Russomando, Graciela; Rousseau, François; Ahmad-Nejad, Parviz

2017-04-01

Multiple organizations produce guidance documents that provide opportunities to harmonize quality practices for diagnostic testing. The International Organization for Standardization ISO 15189 standard addresses requirements for quality in management and technical aspects of the clinical laboratory. One technical aspect addresses the complexities of the pre-examination phase prior to diagnostic testing. The Committee for Molecular Diagnostics of the International Federation for Clinical Chemistry and Laboratory Medicine (also known as, IFCC C-MD) conducted a survey of international molecular laboratories and determined ISO 15189 to be the most referenced guidance document. In this review, the IFCC C-MD provides case-based examples illustrating the value of select pre-examination processes as these processes relate to molecular diagnostic testing. Case-based examples in infectious disease, oncology, inherited disease and pharmacogenomics address the utility of: 1) providing information to patients and users, 2) designing requisition forms, 3) obtaining informed consent and 4) maintaining sample integrity prior to testing. The pre-examination phase requires extensive and consistent communication between the laboratory, the healthcare provider and the end user. The clinical vignettes presented in this paper illustrate the value of applying select ISO 15189 recommendations for general laboratory to the more specialized area of Molecular Diagnostics. Copyright © 2016 Elsevier B.V. All rights reserved.

Interlaboratory tests to identify irradiation treatment of various foods via gas chromatographic detection of hydrocarbons, ESR spectroscopy and TL analysis

Energy Technology Data Exchange (ETDEWEB)

Schreiber, G.A.; Helle, N.; Schulzki, G.; Linke, B.; Spiegelberg, A.; Mager, M.; Boegl, K.W. [BgVV - Federal Inst. for Health Protection of Consumers and Veterinary Medicine, Berlin (Germany)

1996-12-31

The gas chromatographic (GC) analysis of radiation-induced volatile hydrocarbons (HC) and 2-alkylcyclobutanones, the ESR spectroscopic detection of radiation-specific radicals and the thermoluminescence (TL) analysis of silicate mineral are the most important methods for identification of irradiated foods. After successful performance in interlaboratory studies on meat products, fish, spices, herbs and shells of nuts, all or some of these methods have been approved by national authorities in Germany and the United Kingdom. Recently, draft European Standards have been elaborated for approval by member states of the European Committee for Standardization (CEN). Several research laboratories have shown that these methods can be applied to various foods not yet tested in collaborative studies. However, for an effective application in food control it is necessary to prove their suitability in interlaboratory studies. Therefore, in 1993/94, various interlaboratory tests were organised by the BgVV. In an ESR spectroscopic test, shrimps and paprika powder were examined. Shrimps were also the subject of examination in a TL test. Finally, GC detection of radiation-induced hydrocarbons in the fat fraction of foods was used in another test to identify irradiated Camembert, avocado, papaya and mango. In the following paper, results of the interlaboratory tests are summarised. Detailed reports are published by this institute. (author).

Interlaboratory tests to identify irradiation treatment of various foods via gas chromatographic detection of hydrocarbons, ESR spectroscopy and TL analysis

International Nuclear Information System (INIS)

Schreiber, G.A.; Helle, N.; Schulzki, G.; Linke, B.; Spiegelberg, A.; Mager, M.; Boegl, K.W.

1996-01-01

The gas chromatographic (GC) analysis of radiation-induced volatile hydrocarbons (HC) and 2-alkylcyclobutanones, the ESR spectroscopic detection of radiation-specific radicals and the thermoluminescence (TL) analysis of silicate mineral are the most important methods for identification of irradiated foods. After successful performance in interlaboratory studies on meat products, fish, spices, herbs and shells of nuts, all or some of these methods have been approved by national authorities in Germany and the United Kingdom. Recently, draft European Standards have been elaborated for approval by member states of the European Committee for Standardization (CEN). Several research laboratories have shown that these methods can be applied to various foods not yet tested in collaborative studies. However, for an effective application in food control it is necessary to prove their suitability in interlaboratory studies. Therefore, in 1993/94, various interlaboratory tests were organised by the BgVV. In an ESR spectroscopic test, shrimps and paprika powder were examined. Shrimps were also the subject of examination in a TL test. Finally, GC detection of radiation-induced hydrocarbons in the fat fraction of foods was used in another test to identify irradiated Camembert, avocado, papaya and mango. In the following paper, results of the interlaboratory tests are summarised. Detailed reports are published by this institute. (author)

Evaluation of the suitability of chromatographic systems to predict human skin permeation of neutral compounds.

Science.gov (United States)

Hidalgo-Rodríguez, Marta; Soriano-Meseguer, Sara; Fuguet, Elisabet; Ràfols, Clara; Rosés, Martí

2013-12-18

Several chromatographic systems (three systems of high-performance liquid chromatography and two micellar electrokinetic chromatography systems) besides the reference octanol-water partition system are evaluated by a systematic procedure previously proposed in order to know their ability to model human skin permeation. The precision achieved when skin-water permeability coefficients are correlated against chromatographic retention factors is predicted within the framework of the solvation parameter model. It consists in estimating the contribution of error due to the biological and chromatographic data, as well as the error coming from the dissimilarity between the human skin permeation and the chromatographic systems. Both predictions and experimental tests show that all correlations are greatly affected by the considerable uncertainty of the skin permeability data and the error associated to the dissimilarity between the systems. Correlations with much better predictive abilities are achieved when the volume of the solute is used as additional variable, which illustrates the main roles of both lipophilicity and size of the solute to penetrate through the skin. In this way, the considered systems are able to give precise estimations of human skin permeability coefficients. In particular, the HPLC systems with common C18 columns provide the best performances in emulating the permeation of neutral compounds from aqueous solution through the human skin. As a result, a methodology based on easy, fast, and economical HPLC measurements in a common C18 column has been developed. After a validation based on training and test sets, the method has been applied with good results to the estimation of skin permeation of several hormones and pesticides. Copyright © 2013 Elsevier B.V. All rights reserved.

Optimizing the Immuno-Surface Characteristics for Bio-Sensors and Filters Through Modeling and Experiments

Science.gov (United States)

2005-06-01

immobilization of antibodies o Adsorbed, aminophase, heterobifunctional crosslinkers (GMBS, BMPS, EMCS) o GMBS attaches the most antibodies o ProteinA ...play a role in getting the antigen close enough to the immuno-surface to potentially interact as well as the short range molecular forces that

Appraising and applying evidence about a diagnostic test during a performance-based assessment

Directory of Open Access Journals (Sweden)

Franklin Ellen

2004-10-01

Full Text Available Abstract Background The practice of Evidence-based Medicine requires that clinicians assess the validity of published research and then apply the results to patient care. We wanted to assess whether our soon-to-graduate medical students could appraise and apply research about a diagnostic test within a clinical context and to compare our students with peers trained at other institutions. Methods 4th year medical students who previously had demonstrated competency at probability revision and just starting first-year Internal Medicine residents were used for this research. Following an encounter with a simulated patient, subjects critically appraised a paper about an applicable diagnostic test and revised the patient's pretest probability given the test result. Results The medical students and residents demonstrated similar skills at critical appraisal, correctly answering 4.7 and 4.9, respectively, of 6 questions (p = 0.67. Only one out of 28 (3% medical students and none of the 15 residents were able to correctly complete the probability revision task (p = 1.00. Conclusions This study found that most students completing medical school are able to appraise an article about a diagnostic test but few are able to apply the information from the article to a patient. These findings raise questions about the clinical usefulness of the EBM skills possessed by graduating medical students within the area of diagnostic testing.

Sequential Test Selection by Quantifying of the Reduction in Diagnostic Uncertainty for the Diagnosis of Proximal Caries

Directory of Open Access Journals (Sweden)

Umut Arslan

2013-06-01

Full Text Available Background: In order to determine the presence or absence of a certain disease, multiple diagnostic tests may be necessary. Performance of these tests can be sequentially evaluated. Aims: The aim of the study is to determine the contribution of the test in each step, in reducing diagnostic uncertainty when multiple tests are sequentially used for the diagnosis. Study Design: Diagnostic accuracy study Methods: Radiographs of seventy-three patients of the Department of Dento-Maxillofacial Radiology of Hacettepe University Faculty of Dentistry were assessed. Panoramic (PAN, full mouth intraoral (FM, and bitewing (BW radiographs were used for the diagnosis of proximal caries in the maxillary and mandibular molar regions. Diagnostic performance of radiography was sequentially evaluated by using the reduction in diagnostic uncertainty. Results: FM provided maximum diagnostic information for ruling in potential in the maxillary and mandibular molar regions in the first step. FM provided more diagnostic information than BW radiographs for ruling in the mandibular region in the second step. In the mandibular region, BW radiographs provided more diagnostic information than FM for ruling out in the first step. Conclusion: The presented method in this study provides the clinicians with a solution for the decision of the sequential selection of diagnostic tests for the correct diagnosis of the presence or absence of a certain disease.

Privacy and equality in diagnostic genetic testing.

Science.gov (United States)

Nyrhinen, Tarja; Hietala, Marja; Puukka, Pauli; Leino-Kilpi, Helena

2007-05-01

This study aimed to determine the extent to which the principles of privacy and equality were observed during diagnostic genetic testing according to views held by patients or child patients' parents (n = 106) and by staff (n = 162) from three Finnish university hospitals. The data were collected through a structured questionnaire and analysed using the SAS 8.1 statistical software. In general, the two principles were observed relatively satisfactorily in clinical practice. According to patients/parents, equality in the post-analytic phase and, according to staff, privacy in the pre-analytic phase, involved the greatest ethical problems. The two groups differed in their views concerning pre-analytic privacy. Although there were no major problems regarding the two principles, the differences between the testing phases require further clarification. To enhance privacy protection and equality, professionals need to be given more genetics/ethics training, and patients individual counselling by genetics units staff, giving more consideration to patients' world-view, the purpose of the test and the test result.

Diagnostic accuracy of scapular physical examination tests for shoulder disorders: a systematic review.

Science.gov (United States)

Wright, Alexis A; Wassinger, Craig A; Frank, Mason; Michener, Lori A; Hegedus, Eric J

2013-09-01

To systematically review and critique the evidence regarding the diagnostic accuracy of physical examination tests for the scapula in patients with shoulder disorders. A systematic, computerised literature search of PubMED, EMBASE, CINAHL and the Cochrane Library databases (from database inception through January 2012) using keywords related to diagnostic accuracy of physical examination tests of the scapula. The Quality Assessment of Diagnostic Accuracy Studies tool was used to critique the quality of each paper. Eight articles met the inclusion criteria; three were considered to be of high quality. Of the three high-quality studies, two were in reference to a 'diagnosis' of shoulder pain. Only one high-quality article referenced specific shoulder pathology of acromioclavicular dislocation with reported sensitivity of 71% and 41% for the scapular dyskinesis and SICK scapula test, respectively. Overall, no physical examination test of the scapula was found to be useful in differentially diagnosing pathologies of the shoulder.

Aspects pertinent to the usefulness of a solid phase radio-immuno-sorbent assay for the detection of spermatozoa antibodies in sera of infertility patients

International Nuclear Information System (INIS)

Hinrichs-Reiche, I.

1987-01-01

The solid phase Radio-Immuno-Sorbent Assay (RISA) is a highly sensitive and valid test to detect 125-iodinetagged antibodies to spermatozoa that allows qualitative and quantitative evaluations of sperm-incapacitating immunglobulin Ig G in sera from patients believed to be infertile for immunological reasons. The study failed to reveal any correlations between the results of RISA and those of micro-sperm-agglutination or micro-sperm-immobilisation tests. There was a major body of evidence pointing to possible links between female isoimmunity and male autoimmunity. (TRV) [de

The evaluation and impact of diagnostic tests

International Nuclear Information System (INIS)

Royal, H.D.; McNeil, B.J.

1989-01-01

The authors describe the usefulness of the techniques that are applied to study the role of tests and point out their limitations. In many instances, complex tasks must be oversimplified in order to use currently available analytic tools. Certain tools, such as decision analysis, are useful not only because they can provide insight regarding the most favorable diagnostic/therapeutic strategies but also because they can identify areas where present knowledge is inadequate and thereby help put priorities on areas of research

Bayesian analysis of longitudinal Johne's disease diagnostic data without a gold standard test

DEFF Research Database (Denmark)

Wang, C.; Turnbull, B.W.; Nielsen, Søren Saxmose

2011-01-01

the posterior estimates of the model parameters that provide the basis for inference concerning the accuracy of the diagnostic procedure. Based on the Bayesian approach, the posterior probability distribution of the change-point onset time can be obtained and used as a criterion for infection diagnosis......-point process with a Weibull survival hazard function was used to model the progression of the hidden disease status. The model adjusted for the fixed effects of covariate variables and random effects of subject on the diagnostic testing procedure. Markov chain Monte Carlo methods were used to compute....... An application is presented to an analysis of ELISA and fecal culture test outcomes in the diagnostic testing of paratuberculosis (Johne's disease) for a Danish longitudinal study from January 2000 to March 2003. The posterior probability criterion based on the Bayesian model with 4 repeated observations has...

Evaluation of microscopy and rapid diagnostic tests in screening ...

African Journals Online (AJOL)

Malaria is a life-threatening disease caused by the protozoa of the genus Plasmodium. Infection of individual is through the bites of infected female Anopheles mosquitoes. This study evaluated the performance of microscopy and rapid diagnostic tests (RDTs) in diagnosing malaria. A total of 400 clinically suspected malaria ...

Multiple chromatographic fingerprinting and its application to the quality control of herbal medicines

Energy Technology Data Exchange (ETDEWEB)

Fan Xiaohui [Pharmaceutical Informatics Institute, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310027 (China); Cheng Yiyu [Pharmaceutical Informatics Institute, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310027 (China)]. E-mail: chengyy@zju.edu.cn; Ye Zhengliang [Pharmaceutical Informatics Institute, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310027 (China); Lin Ruichao [National Institute for the Control of Pharmaceutical and Biological Products, Beijing 100050 (China); Qian Zhongzhi [Committee of Chinese Pharmacopoeia, Beijing 100061 (China)

2006-01-12

Recently, chromatographic fingerprinting has become one of the most powerful approaches to quality control of herbal medicines. However, the performance of reported chromatographic fingerprinting constructed by single chromatogram sometimes turns out to be inadequate for complex herbal medicines, such as multi-herb botanical drug products. In this study, multiple chromatographic fingerprinting, which consists of more than one chromatographic fingerprint and represents the whole characteristics of chemical constitutions of the complex medicine, is proposed as a potential strategy in this complicated case. As a typical example, a binary chromatographic fingerprinting of 'Danshen Dropping Pill' (DSDP), the best-sold traditional Chinese medicine in China, was developed. First, two HPLC fingerprints that, respectively, represent chemical characteristics of depsides and saponins of DSDP were developed, which were used to construct binary chromatographic fingerprints of DSDP. Moreover, the authentication and validation of the binary fingerprints were performed. Then, a data-level information fusion method was employed to capture the chemical information encoded in two chromatographic fingerprints. Based on the fusion results, the lot-to-lot consistency and frauds can be determined either using similarity measure or by chemometrics approach. The application of binary chromatographic fingerprinting to consistency assessment and frauds detection of DSDP clearly demonstrated that the proposed method was a powerful approach to quality control of complex herbal medicines.

Prospective evaluation of three rapid diagnostic tests for diagnosis of human leptospirosis.

Directory of Open Access Journals (Sweden)

Marga G A Goris

Full Text Available BACKGROUND: Diagnosis of leptospirosis by the microscopic agglutination test (MAT or by culture is confined to specialized laboratories. Although ELISA techniques are more common, they still require laboratory facilities. Rapid Diagnostic Tests (RDTs can be used for easy point-of-care diagnosis. This study aims to evaluate the diagnostic performance of the RDTs LeptoTek Dri Dot, LeptoTek Lateral Flow, and Leptocheck-WB, prospectively. METHODOLOGY: During 2001 to 2012, one or two of the RDTs at the same time have been applied prior to routine diagnostics (MAT, ELISA and culture on serum specimens from participants sent in for leptospirosis diagnosis. The case definition was based on MAT, ELISA and culture results. Participants not fulfilling the case definition were considered not to have leptospirosis. The diagnostic accuracy was determined based on the 1(st submitted sample and paired samples, either in an overall analysis or stratified according to days post onset of illness. RESULTS: The overall sensitivity and specificity for the LeptoTek Dri Dot was 75% respectively 96%, for the LeptoTek Lateral Flow 78% respectively 95%, and for the Leptocheck-WB 78% respectively 98%. Based on the 1(st submitted sample the sensitivity was low (51% for LeptoTek Dri Dot, 69% for LeptoTek Lateral Flow, and 55% for Leptocheck-WB, but substantially increased when the results of paired samples were combined, although accompanied by a lower specificity (82% respectively 91% for LeptoTek Dri Dot, 86% respectively 84% for LeptoTek Lateral Flow, and 80% respectively 93% for Leptocheck-WB. CONCLUSIONS: All three tests present antibody tests contributing to the diagnosis of leptospirosis, thus supporting clinical suspicion and contributing to awareness. Since the overall sensitivity of the tested RDTs did not exceed 80%, one should be cautious to rely only on an RDT result, and confirmation by reference tests is strongly recommended.

Decision analysis to complete diagnostic research by closing the gap between test characteristics and cost-effectiveness.

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Schaafsma, Joanna D; van der Graaf, Yolanda; Rinkel, Gabriel J E; Buskens, Erik

2009-12-01

The lack of a standard methodology in diagnostic research impedes adequate evaluation before implementation of constantly developing diagnostic techniques. We discuss the methodology of diagnostic research and underscore the relevance of decision analysis in the process of evaluation of diagnostic tests. Overview and conceptual discussion. Diagnostic research requires a stepwise approach comprising assessment of test characteristics followed by evaluation of added value, clinical outcome, and cost-effectiveness. These multiple goals are generally incompatible with a randomized design. Decision-analytic models provide an important alternative through integration of the best available evidence. Thus, critical assessment of clinical value and efficient use of resources can be achieved. Decision-analytic models should be considered part of the standard methodology in diagnostic research. They can serve as a valid alternative to diagnostic randomized clinical trials (RCTs).

Temperature Control of Gas Chromatograph Based on Switched Delayed System Techniques

Directory of Open Access Journals (Sweden)

Xiao-Liang Wang

2014-01-01

Full Text Available We address the temperature control problem of the gas chromatograph. We model the temperature control system of the gas chromatograph into a switched delayed system and analyze the stability by common Lyapunov functional technique. The PI controller parameters can be given based on the proposed linear matrix inequalities (LMIs condition and the designed controller can make the temperature of gas chromatograph track the reference signal asymptotically. An experiment is given to illustrate the effectiveness of the stability criterion.

Lacrimination in Sjogren′s syndrome. Is Schirmer′s test really a useful diagnostic tool?

Directory of Open Access Journals (Sweden)

Bhadoria D

1988-01-01

Full Text Available In the past, Schinier′s test was used as a diagnostic tool in Sjogren′s Syndrome. In this study, a comparison of 100 normal patients with 2l patients with Sjogren′s Syndrome has been made to study its reliability. It has been concluded that Schimer′s test is of a poor diagnostic value in Sjogren′s Syndrome.

Performance tests on new chromatographic material for 99Mo-99mTc generators

International Nuclear Information System (INIS)

Sombrito, Elvira Z.; Bulos, Adelina D.M.

2004-01-01

Technetium-99m continues to be the main workhorse of nuclear medicine in the Philippines. Almost 13TBq of 99m Tc was imported to the country in 2002 supplied as 99m Tc- 99 Mo generators. These generators make use of fission molybdenum adsorbed onto an alumina column. Problems associated with the alumina chromatographic generators arise due to safety and economic issues that would be remedied by gel-type generators using low specific activity reactor-produced molybdenum-99 adsorbed on a high capacity gel column material. The Philippine Nuclear Research Institute (PNRI) exerted efforts in this direction by developing a gel-type column, which showed satisfactory molybdenum adsorptive capacity. Likewise, Kaken Co. in Japan in cooperation with Japan Atomic Energy Research Institute (JAERI) developed a dried form of a gel-type polyzirconium compound (PZC). It is a ready-to-use high molybdenum capacity column material for adsorbing reactor-produced molybedum-99. The performance of this material is being tested under the framework of the FNCA project on Research Reactor Utilization. Performance tests on four batches of PZC were performed using fission molybdenum eluted from a 99 Mo- 99m Tc generator. A total of 3.3 GBq 99 Mo was extracted from an alumina column of a commercial generator and mixed with carrier molybdenum solution. About 0.67 GBq was loaded into each of the 12 x 90 mm column. One batch was prepared and distributed in 1999 and tests showed very poor elution yield of 30%. Three recent batches of PZC (2002) gave elution yields of 71% (Range of 69-75). The adsorptive capacity is 99% with about 4% desorption rate. Elution volume is at 5-6 ml. Daily elution for five days gave from 1.6 to 5.5% variability. The tests were performed all at the same time and a trend of improving elution yield and consistency of daily elution yield was observed with the time of testing nearer to the sample preparation date. X-ray diffraction analysis showed an amorphous structure for

Diagnostic Accuracy of Tests for Polyuria in Lithium-Treated Patients.

Science.gov (United States)

Kinahan, James Conor; NiChorcorain, Aoife; Cunningham, Sean; Freyne, Aideen; Cooney, Colm; Barry, Siobhan; Kelly, Brendan D

2015-08-01

In lithium-treated patients, polyuria increases the risk of dehydration and lithium toxicity. If detected early, it is reversible. Despite its prevalence and associated morbidity in clinical practice, it remains underrecognized and therefore undertreated. The 24-hour urine collection is limited by its convenience and practicality. This study explores the diagnostic accuracy of alternative tests such as questionnaires on subjective polyuria, polydipsia, nocturia (dichotomous and ordinal responses), early morning urine sample osmolality (EMUO), and fluid intake record (FIR). This is a cross-sectional study of 179 lithium-treated patients attending a general adult and an old age psychiatry service. Participants completed the tests after completing an accurate 24-hour urine collection. The diagnostic accuracy of the individual tests was explored using the appropriate statistical techniques. Seventy-nine participants completed all of the tests. Polydipsia severity, EMUO, and FIR significantly differentiated the participants with polyuria (area under the receiver operating characteristic curve of 0.646, 0.760, and 0.846, respectively). Of the tests investigated, the FIR made the largest significant change in the probability that a patient experiences polyuria (3500 mL/24 hours; interval likelihood ratio, 14). Symptomatic questioning, EMUO, and an FIR could be used in clinical practice to inform the prescriber of the probability that a lithium-treated patient is experiencing polyuria.

Concordance in diagnostic testing for respiratory pathogens of Bighorn Sheep

Science.gov (United States)

Reliable diagnostic tests are essential for disease investigation and management. This is particularly true for diseases of free-ranging wildlife where sampling is logistically difficult precluding retesting. Clinical assays for wildlife diseases frequently vary among laboratories because of lack ...

[Application of robustness test for assessment of the measurement uncertainty at the end of development phase of a chromatographic method for quantification of water-soluble vitamins].

Science.gov (United States)

Ihssane, B; Bouchafra, H; El Karbane, M; Azougagh, M; Saffaj, T

2016-05-01

We propose in this work an efficient way to evaluate the measurement of uncertainty at the end of the development step of an analytical method, since this assessment provides an indication of the performance of the optimization process. The estimation of the uncertainty is done through a robustness test by applying a Placquett-Burman design, investigating six parameters influencing the simultaneous chromatographic assay of five water-soluble vitamins. The estimated effects of the variation of each parameter are translated into standard uncertainty value at each concentration level. The values obtained of the relative uncertainty do not exceed the acceptance limit of 5%, showing that the procedure development was well done. In addition, a statistical comparison conducted to compare standard uncertainty after the development stage and those of the validation step indicates that the estimated uncertainty are equivalent. The results obtained show clearly the performance and capacity of the chromatographic method to simultaneously assay the five vitamins and suitability for use in routine application. Copyright © 2015 Académie Nationale de Pharmacie. Published by Elsevier Masson SAS. All rights reserved.

Diagnostic Accuracy of the Slump Test for Identifying Neuropathic Pain in the Lower Limb.

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Urban, Lawrence M; MacNeil, Brian J

2015-08-01

Diagnostic accuracy study with nonconsecutive enrollment. To assess the diagnostic accuracy of the slump test for neuropathic pain (NeP) in those with low to moderate levels of chronic low back pain (LBP), and to determine whether accuracy of the slump test improves by adding anatomical or qualitative pain descriptors. Neuropathic pain has been linked with poor outcomes, likely due to inadequate diagnosis, which precludes treatment specific for NeP. Current diagnostic approaches are time consuming or lack accuracy. A convenience sample of 21 individuals with LBP, with or without radiating leg pain, was recruited. A standardized neurosensory examination was used to determine the reference diagnosis for NeP. Afterward, the slump test was administered to all participants. Reports of pain location and quality produced during the slump test were recorded. The neurosensory examination designated 11 of the 21 participants with LBP/sciatica as having NeP. The slump test displayed high sensitivity (0.91), moderate specificity (0.70), a positive likelihood ratio of 3.03, and a negative likelihood ratio of 0.13. Adding the criterion of pain below the knee significantly increased specificity to 1.00 (positive likelihood ratio = 11.9). Pain-quality descriptors did not improve diagnostic accuracy. The slump test was highly sensitive in identifying NeP within the study sample. Adding a pain-location criterion improved specificity. Combining the diagnostic outcomes was very effective in identifying all those without NeP and half of those with NeP. Limitations arising from the small and narrow spectrum of participants with LBP/sciatica sampled within the study prevent application of the findings to a wider population. Diagnosis, level 4-.

Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies: The PRISMA-DTA Statement.

Science.gov (United States)

McInnes, Matthew D F; Moher, David; Thombs, Brett D; McGrath, Trevor A; Bossuyt, Patrick M; Clifford, Tammy; Cohen, Jérémie F; Deeks, Jonathan J; Gatsonis, Constantine; Hooft, Lotty; Hunt, Harriet A; Hyde, Christopher J; Korevaar, Daniël A; Leeflang, Mariska M G; Macaskill, Petra; Reitsma, Johannes B; Rodin, Rachel; Rutjes, Anne W S; Salameh, Jean-Paul; Stevens, Adrienne; Takwoingi, Yemisi; Tonelli, Marcello; Weeks, Laura; Whiting, Penny; Willis, Brian H

2018-01-23

Systematic reviews of diagnostic test accuracy synthesize data from primary diagnostic studies that have evaluated the accuracy of 1 or more index tests against a reference standard, provide estimates of test performance, allow comparisons of the accuracy of different tests, and facilitate the identification of sources of variability in test accuracy. To develop the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) diagnostic test accuracy guideline as a stand-alone extension of the PRISMA statement. Modifications to the PRISMA statement reflect the specific requirements for reporting of systematic reviews and meta-analyses of diagnostic test accuracy studies and the abstracts for these reviews. Established standards from the Enhancing the Quality and Transparency of Health Research (EQUATOR) Network were followed for the development of the guideline. The original PRISMA statement was used as a framework on which to modify and add items. A group of 24 multidisciplinary experts used a systematic review of articles on existing reporting guidelines and methods, a 3-round Delphi process, a consensus meeting, pilot testing, and iterative refinement to develop the PRISMA diagnostic test accuracy guideline. The final version of the PRISMA diagnostic test accuracy guideline checklist was approved by the group. The systematic review (produced 64 items) and the Delphi process (provided feedback on 7 proposed items; 1 item was later split into 2 items) identified 71 potentially relevant items for consideration. The Delphi process reduced these to 60 items that were discussed at the consensus meeting. Following the meeting, pilot testing and iterative feedback were used to generate the 27-item PRISMA diagnostic test accuracy checklist. To reflect specific or optimal contemporary systematic review methods for diagnostic test accuracy, 8 of the 27 original PRISMA items were left unchanged, 17 were modified, 2 were added, and 2 were omitted. The 27-item

ImmunoGrid: towards agent-based simulations of the human immune system at a natural scale

DEFF Research Database (Denmark)

Halling-Brown, M.; Pappalardo, F.; Rapin, Nicolas

2010-01-01

, such as the European Virtual Physiological Human initiative. Finally, we ask a key question: How long will it take us to resolve these challenges and when can we expect to have fully functional models that will deliver health-care benefits in the form of personalized care solutions and improved disease prevention?......The ultimate aim of the EU-funded ImmunoGrid project is to develop a natural-scale model of the human immune system-that is, one that reflects both the diversity and the relative proportions of the molecules and cells that comprise it-together with the grid infrastructure necessary to apply...... this model to specific applications in the field of immunology. These objectives present the ImmunoGrid Consortium with formidable challenges in terms of complexity of the immune system, our partial understanding about how the immune system works, the lack of reliable data and the scale of computational...

Analyzing chromatographic data using multilevel modeling.

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Wiczling, Paweł

2018-06-01

It is relatively easy to collect chromatographic measurements for a large number of analytes, especially with gradient chromatographic methods coupled with mass spectrometry detection. Such data often have a hierarchical or clustered structure. For example, analytes with similar hydrophobicity and dissociation constant tend to be more alike in their retention than a randomly chosen set of analytes. Multilevel models recognize the existence of such data structures by assigning a model for each parameter, with its parameters also estimated from data. In this work, a multilevel model is proposed to describe retention time data obtained from a series of wide linear organic modifier gradients of different gradient duration and different mobile phase pH for a large set of acids and bases. The multilevel model consists of (1) the same deterministic equation describing the relationship between retention time and analyte-specific and instrument-specific parameters, (2) covariance relationships relating various physicochemical properties of the analyte to chromatographically specific parameters through quantitative structure-retention relationship based equations, and (3) stochastic components of intra-analyte and interanalyte variability. The model was implemented in Stan, which provides full Bayesian inference for continuous-variable models through Markov chain Monte Carlo methods. Graphical abstract Relationships between log k and MeOH content for acidic, basic, and neutral compounds with different log P. CI credible interval, PSA polar surface area.

Plasma diagnostic development and UHV testing for the ALPHA collaboration at Marquette University

Science.gov (United States)

Tharp, T. D.; Alpha Collaboration

2017-10-01

At Marquette, we are developing the next generation of nonneutral plasma diagnostics for the ALPHA experiment at CERN. ALPHA is building a new vertical experiment to test the gravitational interaction of antihydrogen with Earth. This expansion requires significant changes to the design of our plasma diagnostic suites: the next generation of tools must be able to measure plasmas from two directions, and must be capable of operating in a horizontal position. The diagnostic suite includes measurements of plasma density, shape, and temperature. The hardware used includes a MicroChannel Plate (MCP), a Faraday Cup, and an electron gun. In addition, we are building a vacuum chamber to test the viability of 3-d printed components for UHV compatibility, with target pressures of 10-10 mbar.

Comparative Studies on the Radiolabeling and Chromatographic Purification of Some Medically Important Compounds

International Nuclear Information System (INIS)

El-Gizawy, M.A.E.

2013-01-01

The present thesis comprises five basic chapters: The first chapter includes the main idea of our study and its problems, also includes the aim of the work of our study. The second chapter includes the theoretical consideration of the subject. It deals with the general methods of labeling, factors that influence the integrity of labeled compounds, radionuclides used for diagnostic nuclear medicine, production methods and radioactive properties of 123 I, 125 I and 131 I. It includes also the techniques used for the preparation of the radioiodinated compounds especially the electrophilic radioiodination technique. This chapter deals also with the medical imaging, techniques of diagnostic nuclear medicine and the purification of radioiodinated compounds using different chromatographic techniques. Since these radioiodinated compounds are used for diagnosis and therapeutic treatment of human diseases, quality control tests such as determination of chemical purity, radionuclidic purity, radiochemical purity, sterility, pyrogenicity and biodistribution are performed to ensure the purity, the safety and efficiency of these products for the intended nuclear medicine application. The third chapter describes the experimental section; comprising chemicals, reagents, the radionuclides, the equipments and the counting systems used in the study. It describes the electrophilic radioiodination using chloramine-T (CAT), iodogen and lactoperoxidase oxidizing agents and the factors affecting the radiochemical yield of the radioiodination of histamine and L-tyrosine methyl ester such as substrate concentration, ph of the medium, reaction time, temperature and stability of the labeled product. This chapter also includes the techniques used in the Purification of radioiodinated compounds, including paper electrophoresis, thin layer chromatography (TLC), Poly acrylamide-acrylic acid resin [P(AAm-AA) resin] and high performance liquid chromatography (HPLC), in addition, the quality control

Immuno-Oncology Biomarkers for Gastric and Gastroesophageal Junction Adenocarcinoma: Why PD-L1 Testing May Not Be Enough.

Science.gov (United States)

Weinberg, Benjamin A; Xiu, Joanne; Hwang, Jimmy J; Shields, Anthony F; Salem, Mohamed E; Marshall, John L

2018-04-27

The treatment of patients with advanced gastric and gastroesophageal junction (G/GEJ) adenocarcinomas has been transformed by the U.S. Food and Drug Administration approval of pembrolizumab. Tumor and adjacent tissue must stain positively for the programmed cell death ligand 1 (PD-L1) protein by companion diagnostic testing. However, some patients with PD-L1-negative tumors also benefit from pembrolizumab. High microsatellite instability (MSI) and tumor mutational load (TML) are positive predictive biomarkers for immune checkpoint inhibition (ICI) in other tumors. We sought to identify more patients who could benefit from ICI using alternative PD-L1 thresholds, MSI, and TML. Tumor specimens underwent next-generation sequencing (NGS) and PD-L1 testing using immunohistochemistry. NGS was used to determine TML and MSI. We profiled 581 G/GEJ adenocarcinoma specimens. PD-L1 staining was scored for intensity (0, none; 1+, weak; 2+, moderate; 3+, strong). Using 2+ staining at a 5% threshold, 9.3% of tumors were PD-L1 positive, and using 1+ staining at 1%, 16.2% were PD-L1 positive. 6.9% of tumors had high MSI. High TML (≥17 mutations per megabase) was seen in 6.9%, and medium TML (≥7) was seen in 56.5% of tumors. Thirty (5.2%) PD-L1-negative tumors at the 1+, 1% threshold had high TML or high MSI. Primary tumors had higher rates of high TML (8.8% vs. 3.9%; p  = .0377) and high MSI (8.5% vs. 3.9%; p  = .0471) than metastases. PD-L1 testing alone fails to detect patients who may benefit from ICI. Lower PD-L1 thresholds and TML testing should be considered in future clinical trials. Pembrolizumab is approved by the U.S. Food and Drug Administration for patients with refractory gastric and gastroesophageal cancers if the tumor and adjacent tissue stain positively for the programmed cell death ligand 1 (PD-L1) protein by companion diagnostic testing. Tumor mutational load, microsatellite instability (MSI), and alternative PD-L1 testing thresholds may serve as

Hydrocarbon Fuel Thermal Performance Modeling based on Systematic Measurement and Comprehensive Chromatographic Analysis

Science.gov (United States)

2016-07-31

distribution unlimited Hydrocarbon Fuel Thermal Performance Modeling based on Systematic Measurement and Comprehensive Chromatographic Analysis Matthew...vital importance for hydrocarbon -fueled propulsion systems: fuel thermal performance as indicated by physical and chemical effects of cooling passage... analysis . The selection and acquisition of a set of chemically diverse fuels is pivotal for a successful outcome since test method validation and

Cost-effectiveness of using a molecular diagnostic test to improve preoperative diagnosis of thyroid cancer.

Science.gov (United States)

Najafzadeh, Mehdi; Marra, Carlo A; Lynd, Larry D; Wiseman, Sam M

2012-12-01

Fine-needle aspiration biopsy (FNAB) is a safe and inexpensive diagnostic procedure for evaluating thyroid nodules.Up to 25% of the results from an FNAB, however, may not be diagnostic or may be indeterminate, leading to a subsequent diagnostic thyroid surgery. A new molecularly based diagnostic test could potentially reduce indeterminate cytological results and, with high accuracy, provide a definitive diagnosis for cancer in thyroid nodules. The aim of the study was to estimate the cost-effectiveness of utilizing a molecular diagnostic (DX) test as an adjunct to FNAB, compared with NoDX, to improve the preoperative diagnosis of thyroid nodules. We constructed a patient-level simulation model to estimate the clinical and economic outcomes of using a DX test compared with current practice (NoDX) for the diagnosis of thyroid nodules. By using a cost-effectiveness framework, we measured incremental clinical benefits in terms of quality-adjusted life-years and incremental costs over a 10-year time horizon. Assuming 95% sensitivity and specificity of the Dx test when used as an adjunct to FNAB, the utilization of the DX test resulted in a gain of 0.046 quality-adjusted life-years (95% confidence interval 0.019-0.078) and a saving of $1087 (95% confidence interval $691-$1533) in direct costs per patient. If the cost of the Dx test is less than $1087 per test, we expect to save quality-adjusted life-years and reduce costs when it is utilized. Sensitivity of the DX test, compared with specificity, had a larger influence on the overall outcomes. Copyright © 2012 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Classification of chronic orofacial pain using an intravenous diagnostic test

NARCIS (Netherlands)

Tjakkes, G. -H. E.; De Bont, L. G. M.; van Wijhe, M.; Stegenga, B.

The aim of this study was to evaluate the ability of a preliminary intravenous diagnostic test to classify chronic orofacial pain patients into different subgroups. Patients with chronic orofacial pain conditions that could not be unambiguously diagnosed. A retrospective evaluation of series of

Mixed-mode chromatographic matrices for the resolution of transfer ribonucleic acids

NARCIS (Netherlands)

Bischoff, Rainer; Mclaughlin, L.W.

1984-01-01

Modification of approximately 65% of the amine groups of an aminopropylsilyl bonded-phase silica high-performance liquid chromatographic anion exchanger (APS-Hypersil) with organic acids containing n-alkyl moieties of different chain lengths, results in mixed mode chromatographic matrices of varying

Radioimmunoassay of methaqualone in human urine compared with chromatographic methods

International Nuclear Information System (INIS)

Mule, S.J.; Kogan, M.; Jukofsky, D.

1978-01-01

The 125 I-radioimmunoassay for methaqualone in human urine was evaluated by a comparison with newly modified gas-liquid chromatographic and thin-layer chromatographic methods. The statistically significant sensitivity value for the radioimmunoassay was at 2 μg of methaqualone per liter of urine. The coefficient of variation was 2.88 -+ 0.16% intraassay. There was cross-reactivity only with metabolites of methaqualone, 4'-hydroxymethaqualone being twice as sensitively measured as methaqualone. There was complete agreement between results by radioimmunoassay and by gas-liquid chromatography in 96.7% of the samples analyzed. Only 1.2% of the radioimmunoassay values were false positives, and 2.1% false negatives (phi = 0.8917, P < 0.001). Comparisons between the thin-layer chromatographic data and the gas--liquid chromatographic or radioimmunoassay data showed less agreement because of the 50- to 200-fold higher sensitivity of the latter techniques. Gas--liquid chromatography therefore appears to represent the best reference method for the evaluation of the radioimmunoassay, which appears to be a very sensitive and reliable technique for detecting methaqualone and its metabolites in human urine

Portuguese Family Physicians' Awareness of Diagnostic and Laboratory Test Costs: A Cross-Sectional Study.

Directory of Open Access Journals (Sweden)

Luísa Sá

Full Text Available Physicians' ability to make cost-effective decisions has been shown to be affected by their knowledge of health care costs. This study assessed whether Portuguese family physicians are aware of the costs of the most frequently prescribed diagnostic and laboratory tests.A cross-sectional study was conducted in a representative sample of Portuguese family physicians, using computer-assisted telephone interviews for data collection. A Likert scale was used to assess physician's level of agreement with four statements about health care costs. Family physicians were also asked to estimate the costs of diagnostic and laboratory tests. Each physician's cost estimate was compared with the true cost and the absolute error was calculated.One-quarter (24%; 95% confidence interval: 23%-25% of all cost estimates were accurate to within 25% of the true cost, with 55% (95% IC: 53-56 overestimating and 21% (95% IC: 20-22 underestimating the true actual cost. The majority (76% of family physicians thought they did not have or were uncertain as to whether they had adequate knowledge of diagnostic and laboratory test costs, and only 7% reported receiving adequate education. The majority of the family physicians (82% said that they had adequate access to information about the diagnostic and laboratory test costs. Thirty-three percent thought that costs did not influence their decision to order tests, while 27% were uncertain.Portuguese family physicians have limited awareness of diagnostic and laboratory test costs, and our results demonstrate a need for improved education in this area. Further research should focus on identifying whether interventions in cost knowledge actually change ordering behavior, in identifying optimal methods to disseminate cost information, and on improving the cost-effectiveness of care.

Portuguese Family Physicians’ Awareness of Diagnostic and Laboratory Test Costs: A Cross-Sectional Study

Science.gov (United States)

Sá, Luísa; Costa-Santos, Cristina; Teixeira, Andreia; Couto, Luciana; Costa-Pereira, Altamiro; Hespanhol, Alberto; Santos, Paulo; Martins, Carlos

2015-01-01

Background Physicians’ ability to make cost-effective decisions has been shown to be affected by their knowledge of health care costs. This study assessed whether Portuguese family physicians are aware of the costs of the most frequently prescribed diagnostic and laboratory tests. Methods A cross-sectional study was conducted in a representative sample of Portuguese family physicians, using computer-assisted telephone interviews for data collection. A Likert scale was used to assess physician’s level of agreement with four statements about health care costs. Family physicians were also asked to estimate the costs of diagnostic and laboratory tests. Each physician’s cost estimate was compared with the true cost and the absolute error was calculated. Results One-quarter (24%; 95% confidence interval: 23%–25%) of all cost estimates were accurate to within 25% of the true cost, with 55% (95% IC: 53–56) overestimating and 21% (95% IC: 20–22) underestimating the true actual cost. The majority (76%) of family physicians thought they did not have or were uncertain as to whether they had adequate knowledge of diagnostic and laboratory test costs, and only 7% reported receiving adequate education. The majority of the family physicians (82%) said that they had adequate access to information about the diagnostic and laboratory test costs. Thirty-three percent thought that costs did not influence their decision to order tests, while 27% were uncertain. Conclusions Portuguese family physicians have limited awareness of diagnostic and laboratory test costs, and our results demonstrate a need for improved education in this area. Further research should focus on identifying whether interventions in cost knowledge actually change ordering behavior, in identifying optimal methods to disseminate cost information, and on improving the cost-effectiveness of care. PMID:26356625

Dual Processing Model for Medical Decision-Making: An Extension to Diagnostic Testing.

Science.gov (United States)

Tsalatsanis, Athanasios; Hozo, Iztok; Kumar, Ambuj; Djulbegovic, Benjamin

2015-01-01

Dual Processing Theories (DPT) assume that human cognition is governed by two distinct types of processes typically referred to as type 1 (intuitive) and type 2 (deliberative). Based on DPT we have derived a Dual Processing Model (DPM) to describe and explain therapeutic medical decision-making. The DPM model indicates that doctors decide to treat when treatment benefits outweigh its harms, which occurs when the probability of the disease is greater than the so called "threshold probability" at which treatment benefits are equal to treatment harms. Here we extend our work to include a wider class of decision problems that involve diagnostic testing. We illustrate applicability of the proposed model in a typical clinical scenario considering the management of a patient with prostate cancer. To that end, we calculate and compare two types of decision-thresholds: one that adheres to expected utility theory (EUT) and the second according to DPM. Our results showed that the decisions to administer a diagnostic test could be better explained using the DPM threshold. This is because such decisions depend on objective evidence of test/treatment benefits and harms as well as type 1 cognition of benefits and harms, which are not considered under EUT. Given that type 1 processes are unique to each decision-maker, this means that the DPM threshold will vary among different individuals. We also showed that when type 1 processes exclusively dominate decisions, ordering a diagnostic test does not affect a decision; the decision is based on the assessment of benefits and harms of treatment. These findings could explain variations in the treatment and diagnostic patterns documented in today's clinical practice.

Dual Processing Model for Medical Decision-Making: An Extension to Diagnostic Testing.

Directory of Open Access Journals (Sweden)

Athanasios Tsalatsanis

Full Text Available Dual Processing Theories (DPT assume that human cognition is governed by two distinct types of processes typically referred to as type 1 (intuitive and type 2 (deliberative. Based on DPT we have derived a Dual Processing Model (DPM to describe and explain therapeutic medical decision-making. The DPM model indicates that doctors decide to treat when treatment benefits outweigh its harms, which occurs when the probability of the disease is greater than the so called "threshold probability" at which treatment benefits are equal to treatment harms. Here we extend our work to include a wider class of decision problems that involve diagnostic testing. We illustrate applicability of the proposed model in a typical clinical scenario considering the management of a patient with prostate cancer. To that end, we calculate and compare two types of decision-thresholds: one that adheres to expected utility theory (EUT and the second according to DPM. Our results showed that the decisions to administer a diagnostic test could be better explained using the DPM threshold. This is because such decisions depend on objective evidence of test/treatment benefits and harms as well as type 1 cognition of benefits and harms, which are not considered under EUT. Given that type 1 processes are unique to each decision-maker, this means that the DPM threshold will vary among different individuals. We also showed that when type 1 processes exclusively dominate decisions, ordering a diagnostic test does not affect a decision; the decision is based on the assessment of benefits and harms of treatment. These findings could explain variations in the treatment and diagnostic patterns documented in today's clinical practice.

Development, Evaluation, and Integration of a Quantitative Reverse-Transcription Polymerase Chain Reaction Diagnostic Test for Ebola Virus on a Molecular Diagnostics Platform.

Science.gov (United States)

Cnops, Lieselotte; Van den Eede, Peter; Pettitt, James; Heyndrickx, Leo; De Smet, Birgit; Coppens, Sandra; Andries, Ilse; Pattery, Theresa; Van Hove, Luc; Meersseman, Geert; Van Den Herrewegen, Sari; Vergauwe, Nicolas; Thijs, Rein; Jahrling, Peter B; Nauwelaers, David; Ariën, Kevin K

2016-10-15

 The 2013-2016 Ebola epidemic in West Africa resulted in accelerated development of rapid diagnostic tests for emergency outbreak preparedness. We describe the development and evaluation of the Idylla™ prototype Ebola virus test, a fully automated sample-to-result molecular diagnostic test for rapid detection of Zaire ebolavirus (EBOV) and Sudan ebolavirus (SUDV).  The Idylla™ prototype Ebola virus test can simultaneously detect EBOV and SUDV in 200 µL of whole blood. The sample is directly added to a disposable cartridge containing all reagents for sample preparation, RNA extraction, and amplification by reverse-transcription polymerase chain reaction analysis. The performance was evaluated with a variety of sample types, including synthetic constructs and whole blood samples from healthy volunteers spiked with viral RNA, inactivated virus, and infectious virus.  The 95% limits of detection for EBOV and SUDV were 465 plaque-forming units (PFU)/mL (1010 copies/mL) and 324 PFU/mL (8204 copies/mL), respectively. In silico and in vitro analyses demonstrated 100% correct reactivity for EBOV and SUDV and no cross-reactivity with relevant pathogens. The diagnostic sensitivity was 97.4% (for EBOV) and 91.7% (for SUDV), the specificity was 100%, and the diagnostic accuracy was 95.9%.  The Idylla™ prototype Ebola virus test is a fast, safe, easy-to-use, and near-patient test that meets the performance criteria to detect EBOV in patients with suspected Ebola. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

In Search of Optimal Cognitive Diagnostic Model(s) for ESL Grammar Test Data

Science.gov (United States)

Yi, Yeon-Sook

2017-01-01

This study compares five cognitive diagnostic models in search of optimal one(s) for English as a Second Language grammar test data. Using a unified modeling framework that can represent specific models with proper constraints, the article first fit the full model (the log-linear cognitive diagnostic model, LCDM) and investigated which model…

Consensus-based reporting standards for diagnostic test accuracy studies for paratuberculosis in ruminants

DEFF Research Database (Denmark)

Gardner, Ian A.; Nielsen, Søren Saxmose; Whittington, Richard

2011-01-01

The Standards for Reporting of Diagnostic Accuracy (STARD) statement (www.stard-statement.org) was developed to encourage complete and transparent reporting of key elements of test accuracy studies in human medicine. The statement was motivated by widespread evidence of bias in test accuracy...... studies and the finding that incomplete or absent reporting of items in the STARD checklist was associated with overly optimistic estimates of test performance characteristics. Although STARD principles apply broadly, specific guidelines do not exist to account for unique considerations in livestock...... for Reporting of Animal Diagnostic Accuracy Studies for paratuberculosis), should facilitate improved quality of reporting of the design, conduct and results of paratuberculosis test accuracy studies which were identified as “poor” in a review published in 2008 in Veterinary Microbiology...

[Diagnostic agreement between two glycosylated a1b hemoglobin methods in Primary Care].

Science.gov (United States)

Villar-del-Campo, M C; Rodríguez-Caravaca, G; Gil-Yonte, P; Cidoncha-Calderón, E; García-Cruces Méndez, J; Donnay-Pérez, S

2014-01-01

Several methods are available for measuring glycosylated A1c hemoglobin (HbA1c), all rapid methods for point of care use in a clinical or laboratory setting. This study attempts to compare the diagnostic agreement between two methods for detection of HbA1c. A descriptive cross-sectional study of diagnostic agreement was carried out in the Los Carmenes Health Centre. Two groups of patients -with and without type 2 diabetes- were consecutively included. A method for point-of-care use in a Primary Care Clinic setting (DCA(TM) Systems Siemens(®)) was compared with a laboratory test (chromatographic analysis). An analysis was made of the mean concentration of HbA1c, the agreement between methods, using the intra-class correlation coefficient (CCLA1) and the Bland-Altman method. A total of 102 patients were included, 62 diabetic (60.8%) and 40 non-diabetic (39.2%). The overall mean HbA1c was 6.46% (SD=0.88) in the analysis using capillary blood in the clinic with the DCA™ system, and 6.44% (SD=0.86) using the laboratory test (P>.05). The degree of agreement between the two tests was 0.975 (95% CI: 0.963-0.983). The mean of the differences between the results of the two assessed tests was 0.024 (SD=0.27). The percentage of points outside the limits of optimal agreement, as defined in the Bland-Altman graph, was 2.5%. Diagnostic agreement between a method for point-of-care use in a Primary Health Care Clinic and a laboratory test was very high. Detection at the point-of-care allows a quick and simple assessment of HbA1c. Copyright © 2013 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España. All rights reserved.

Studying the Impact of Spaceflight Environment on Immune Functions Using New Molecular Diagnostics System

Science.gov (United States)

Cohen, Luchino

Immune functions are altered during space flights. Latent virus reactivation, reduction in the number of immune cells, decreased cell activation and increased sensitivity of astronauts to infections following their return on Earth demonstrate that the immune system is less efficient during space flight. The causes of this immune deficiency are not fully understood and this dysfunction during long-term missions could result in the appearance of opportunistic infections or a decrease in the immuno-surveillance mechanisms that eradicate cancer cells. Therefore, the immune functions of astronauts will have to be monitored continuously during long-term missions in space, using miniature and semi-automated diagnostic systems. The objectives of this project are to study the causes of space-related immunodeficiency, to develop countermeasures to maintain an optimal immune function and to improve our capacity to detect infectious diseases during space missions through the monitoring of astronauts' immune system. In order to achieve these objectives, an Immune Function Diagnostic System (IFDS) will be designed to perform a set of immunological assays on board spacecrafts or on planet-bound bases. Through flow cytometric assays and molecular biology analyses, this diagnostic system could improve medical surveillance of astronauts and could be used to test countermeasures aimed at preventing immune deficiency during space missions. The capacity of the instrument to assess cellular fluorescence and to quantify the presence of soluble molecules in biological samples would support advanced molecular studies in space life sciences. Finally, such diagnostic system could also be used on Earth in remote areas or in mobile hospitals following natural disasters to fight against infectious diseases and other pathologies.

Convergent and diagnostic validity of STAVUX, a word and pseudoword spelling test for adults.

Science.gov (United States)

Östberg, Per; Backlund, Charlotte; Lindström, Emma

2016-10-01

Few comprehensive spelling tests are available in Swedish, and none have been validated in adults with reading and writing disorders. The recently developed STAVUX test includes word and pseudoword spelling subtests with high internal consistency and adult norms stratified by education. This study evaluated the convergent and diagnostic validity of STAVUX in adults with dyslexia. Forty-six adults, 23 with dyslexia and 23 controls, took STAVUX together with a standard word-decoding test and a self-rated measure of spelling skills. STAVUX subtest scores showed moderate to strong correlations with word-decoding scores and predicted self-rated spelling skills. Word and pseudoword subtest scores both predicted dyslexia status. Receiver-operating characteristic (ROC) analysis showed excellent diagnostic discriminability. Sensitivity was 91% and specificity 96%. In conclusion, the results of this study support the convergent and diagnostic validity of STAVUX.

A new condition for assessing the clinical efficiency of a diagnostic test.

Science.gov (United States)

Bokhari, Ehsan; Hubert, Lawrence

2015-09-01

When prediction using a diagnostic test outperforms simple prediction using base rates, the test is said to be "clinically efficient," a term first introduced into the literature by Meehl and Rosen (1955) in Psychological Bulletin. This article provides three equivalent conditions for determining the clinical efficiency of a diagnostic test: (a) Meehl-Rosen (Meehl & Rosen, 1955); (b) Dawes (Dawes, 1962); and (c) the Bokhari-Hubert condition, introduced here for the first time. Clinical efficiency is then generalized to situations where misclassification costs are considered unequal (for example, false negatives are more costly than false positives). As an illustration, the clinical efficiency of an actuarial device for predicting violent and dangerous behavior is examined that was developed as part of the MacArthur Violence Risk Assessment Study. (c) 2015 APA, all rights reserved.

The Relationship Between Human Nucleolar Organizer Regions and Nucleoli, Probed by 3D-ImmunoFISH.

Science.gov (United States)

van Sluis, Marjolein; van Vuuren, Chelly; McStay, Brian

2016-01-01

3D-immunoFISH is a valuable technique to compare the localization of DNA sequences and proteins in cells where three-dimensional structure has been preserved. As nucleoli contain a multitude of protein factors dedicated to ribosome biogenesis and form around specific chromosomal loci, 3D-immunoFISH is a particularly relevant technique for their study. In human cells, nucleoli form around transcriptionally active ribosomal gene (rDNA) arrays termed nucleolar organizer regions (NORs) positioned on the p-arms of each of the acrocentric chromosomes. Here, we provide a protocol for fixing and permeabilizing human cells grown on microscope slides such that nucleolar proteins can be visualized using antibodies and NORs visualized by DNA FISH. Antibodies against UBF recognize transcriptionally active rDNA/NORs and NOP52 antibodies provide a convenient way of visualizing the nucleolar volume. We describe a probe designed to visualize rDNA and introduce a probe comprised of NOR distal sequences, which can be used to identify or count individual NORs.

Chromatographic and biological aspects of organomercurials

Energy Technology Data Exchange (ETDEWEB)

Fishbein, L

1970-01-01

A thorough review on the biological and chromatographic aspects of methylmercury, phenylmercurials, and miscellaneous organomercurials is presented. Areas covered include ecology, epidemiology, paper chromatography, thin-layer chromatography, gas chromatography, metabolism and toxicity, and environmental degradation. 183 references.

Quality assurance in diagnostic radiology in Hungary - first experiences in acceptance testing

International Nuclear Information System (INIS)

Porubszky, T.; Pellet, S.; Ballay, L.; Talian, L.; Giczi, F.

2003-01-01

It is a general experience that optimum imaging with minimum patient doses, moreover, the safe operation and long life of X-ray equipment can be assured by regular measurement of technical parameters and checking of their constancy (routine performance testing) only. These tests are generally known as quality control, while together with the so-called corrective actions and its management it is called (physical-technical) quality assurance (QA). In the European Union, Directive 97/43/EURATOM about radiation protection of patients requires - among others - the good practice of (physical-technical) quality assurance. In Hungary, Decree No. 31/2001. (X.3.) of the Minister of Health harmonizes all of its requirements. Acceptance testing of new diagnostic X-ray equipment is assigned to NPHC-NRIRR. QA has been a daily practice in radiation therapy and nuclear medicine for a long time. A National Patient Dose Assessment Programme has also successfully run since 1989. We had, however, only few preliminaries in QA in diagnostic radiology in the second half of the eighties. Nowadays there are running QA programmes in some hospitals and mammography centres. he testing activity of our institute is independent from manufacturers, it is run within the frame of an accredited testing laboratory, using calibrated measuring instruments and based on valid international standards. So the started way of implementing QA in diagnostic radiology needs a lot of further efforts, adapting experiences of other countries, and also some financial help to reach an acceptable level in the EU. (authors)

2012 HIV Diagnostics Conference: the molecular diagnostics perspective.

Science.gov (United States)

Branson, Bernard M; Pandori, Mark

2013-04-01

2012 HIV Diagnostic Conference Atlanta, GA, USA, 12-14 December 2012. This report highlights the presentations and discussions from the 2012 National HIV Diagnostic Conference held in Atlanta (GA, USA), on 12-14 December 2012. Reflecting changes in the evolving field of HIV diagnostics, the conference provided a forum for evaluating developments in molecular diagnostics and their role in HIV diagnosis. In 2010, the HIV Diagnostics Conference concluded with the proposal of a new diagnostic algorithm which included nucleic acid testing to resolve discordant screening and supplemental antibody test results. The 2012 meeting, picking up where the 2010 meeting left off, focused on scientific presentations that assessed this new algorithm and the role played by RNA testing and new developments in molecular diagnostics, including detection of total and integrated HIV-1 DNA, detection and quantification of HIV-2 RNA, and rapid formats for detection of HIV-1 RNA.

Chromatographic methods

International Nuclear Information System (INIS)

Marhol, M.; Stary, J.

1975-01-01

The characteristics are given of chromatographic separation and the methods are listed. Methods and data on materials used in partition, adsorption, precipitation and ion exchange chromatography are listed and conditions are described under which ion partition takes place. Special attention is devoted to ion exchange chromatography where tables are given to show the course of values of the partition coefficients of different ions in dependence on the concentration of agents and the course of equilibrium sorptions on different materials in dependence on the solution pH. A theoretical analysis is given and the properties of the most widely used ion exchangers are listed. Experimental conditions and apparatus used for each type of chromatography are listed. (L.K.)

Isotopic methods or immuno diagnosis: The Radioimmunoassay and immunoradiometric assay

International Nuclear Information System (INIS)

Caso, R.

1997-01-01

This work offers an explanation about the more used isotopic techniques for immuno diagnosis: the radioimmunoassay (RIA) and immunoradiometric assay (IRMA). It describes the basic principles of these assays, the antigen-antibody reaction, the radioiodination methods with I-125 for antigens and antibodies, the purification and characterization of labelled compounds. On the order hand they present work gives a review of the methods for separate the bound and free fractions. At the end it offers the principles of the quality control of immunoassay and the future lines of research in the field of RIA and IRMA

Culture-independent diagnostic testing: have we opened Pandora's box for good?

Science.gov (United States)

Janda, J Michael; Abbott, Sharon A

2014-11-01

The ability to accurately and quickly identify microbial agents associated with infectious diseases has been a longstanding and continuous goal of diagnostic microbiology laboratories. Over the course of several decades, technology and testing methodologies in this field have gradually evolved from traditional- or classic-based culture and identification approaches to antigen capture systems and more molecular-oriented applications. Recently, these molecular-based applications have signaled a new era in clinical diagnostic microbiology with the commercial introduction of culture-independent diagnostic testing (CIDT) systems. The first major commercial venture into the CIDT arena involves the detection of acute bacterial gastroenteritis. Several commercial products are now on the market globally with at least 4 Food and Drug Administration approved since January of 2013. These new systems offer the direct detection of a variety of enteropathogens quickly without the need for traditional culture. In Greek mythology, Pandora opened a "jar" or "box" out of curiosity thereby releasing all of humanity's evils most notably diseases and plagues according to Hesiod's Theogony. While not ill-intentioned the only thing left in the box was Hope. Copyright © 2014 Elsevier Inc. All rights reserved.

Usage of Latent Class Analysis in Diagnostic Microbiology in the Absence of Gold Standard Test

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Gul Bayram Abiha

2016-12-01

Full Text Available The evaluation of performance of various tests diagnostic tests in the absence of gold standard is an important problem. Latent class analysis (LCA is a statistical analysis method known for many years, especially in the absence of a gold standard for evaluation of diagnostic tests so that LCA has found its wide application area. During the last decade, LCA method has widely used in for determining sensivity and specifity of different microbiological tests. It has investigated in the diagnosis of mycobacterium tuberculosis, mycobacterium bovis, human papilloma virus, bordetella pertussis, influenza viruses, hepatitis E virus (HEV, hepatitis C virus (HCV and other various viral infections. Researchers have compared several diagnostic tests for the diagnosis of different pathogens with LCA. We aimed to evaluate performance of latent class analysis method used microbiological diagnosis in various diseases in several researches. When we took into account all of these tests' results, we suppose that LCA is a good statistical analysis method to assess different test performances in the absence of gold standard. [Archives Medical Review Journal 2016; 25(4.000: 467-488

Laboratory evaluation of immunochromatographic rapid diagnostic tests for cholera in Haiti.

Directory of Open Access Journals (Sweden)

Wilfredo R Matias

Full Text Available Rapid diagnostic tests (RDT for cholera are promising tools for detecting cholera in areas with limited laboratory infrastructure. However, evidence on the characteristics of the many available RDTs is scarce, and their use has been limited by suboptimal performance. We evaluated the performance characteristics of three cholera RDTs from Span Diagnostics, Artron Laboratories, and Standard Diagnostics in a regional laboratory in Haiti.We retrospectively reviewed records from May 2014 to October 2015 of a laboratory-based surveillance program for Vibrio cholerae at Hôpital Saint-Nicolas in Saint-Marc, Haiti. We compared the results of 511 Crystal VC, 129 Artron and 451 SD Bioline RDTs to bacterial culture as the gold standard. Of 905 cultures, 477 (52.7% were positive for V. cholerae O1, of which 27.7% were serotype Inaba. No cultures grew V. cholerae O139. Sensitivity and specificity of Crystal VC were 98.6% (95%CI: 96.5%-99.6% and 71.1% (95%CI: 64.7%-76.9%, respectively. Artron demonstrated a sensitivity of 98.6% (95%CI: 92.7%-100% and specificity of 69.1% (95%CI: 55.2%-80.9%. SD Bioline demonstrated a sensitivity of 81.1% (95%CI: 75.6%-85.8% and specificity of 92.8% (95%CI: 88.4%-95.9%. Crystal VC and Artron frequently showed false positive O139 bands, whereas none were seen with SD Bioline.There is significant variation in the performance of different cholera diagnostic RDTs. Artron and Crystal VC RDTs have high sensitivity and low specificity, while SD Bioline RDT has low to moderate sensitivity and high specificity when performed by laboratory technicians in Haiti. Study limitations included its retrospective design. The suboptimal characteristics of these tests limit their use as clinical point-of-care tests; however, they may be useful in outbreak response, surveillance, and research in resource-limited settings.

Diagnostic accuracy of patch test in children with food allergy.

Science.gov (United States)

Caglayan Sozmen, Sule; Povesi Dascola, Carlotta; Gioia, Edoardo; Mastrorilli, Carla; Rizzuti, Laura; Caffarelli, Carlo

2015-08-01

The gold standard test for confirming whether a child has clinical hypersensitivity reactions to foods is the oral food challenge. Therefore, there is increasing interest in simpler diagnostic markers of food allergy, especially in children, to avoid oral food challenge. The goal of this study was to assess the diagnostic accuracy of atopy patch test in comparison with oral food challenge. We investigated 243 children (mean age, 51 months) referred for evaluation of suspected egg or cow's milk allergy. Skin prick test and atopy patch test were carried out, and after a 2 weeks elimination diet, oral food challenge was performed. Two hundred and forty-three children underwent OFC to the suspected food. We found clinically relevant food allergies in 40 (65%) children to egg and in 22 (35%) to cow's milk. The sensitivity of skin prick test for both milk and egg was 92%, specificity 91%, positive predictive value 35%, and negative predictive value of 93%. Sensitivity, specificity, positive predictive value, and negative predictive value of atopy patch test for both milk and egg were 21%, 73%, 20%, and 74%, respectively. Our study suggests that there is insufficient evidence for the routine use of atopy patch test for the evaluation of egg and cow's milk allergy. OFC remains gold standard for the diagnosis of egg and milk allergy even in the presence of high costs in terms of both time and risks during application. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

A compliance testing program for diagnostic X-ray equipment

International Nuclear Information System (INIS)

Hutchinson, D.E.; Cobb, B.J.; Jacob, C.S.

1999-01-01

Compliance testing is nominally that part of a quality assurance program dealing with those aspects of X-ray equipment performance that are subject to radiation control legislation. Quality assurance programs for medical X-ray equipment should be an integral part of the quality culture in health care. However while major hospitals and individual medical centers may implement such programs with some diligence, much X-ray equipment can remain unappraised unless there is a comprehensive regulatory inspection program or some form of compulsion on the equipment owner to implement a testing program. Since the late 1950s all X-ray equipment in the State of Western Australia has been inspected by authorized officers acting on behalf of the Radiological Council, the regulatory authority responsible for administration of the State's Radiation Safety Act. However, economic constraints, coupled with increasing X-ray equipment numbers and a geographically large State have significantly affected the inspection rate. Data available from inspections demonstrate that regular compliance and performance checks are essential in order to ensure proper performance and to minimize unnecessary patient and operator dose. To ensure that diagnostic X-ray equipment complies with accepted standards and performance criteria, the regulatory authority introduced a compulsory compliance testing program for all medical, dental and chiropractic diagnostic X-ray equipment effective from 1 January 1997

A Quantitative Gas Chromatographic Ethanol Determination.

Science.gov (United States)

Leary, James J.

1983-01-01

Describes a gas chromatographic experiment for the quantitative determination of volume percent ethanol in water ethanol solutions. Background information, procedures, and typical results are included. Accuracy and precision of results are both on the order of two percent. (JN)

The TRIPS (Toll-like receptors in immuno-inflammatory pathogenesis) Hypothesis: a novel postulate to understand schizophrenia.

Science.gov (United States)

Venkatasubramanian, Ganesan; Debnath, Monojit

2013-07-01

Mounting evidence indicates that immune activation and/or immuno-inflammatory reactions during neurodevelopment apparently contribute to the pathogenesis and progression of schizophrenia. One of the important environmental factors that is known to trigger immune activation/inflammatory responses during early pregnancy is prenatal infection. Recent understanding from animal studies suggests that prenatal infection induced maternal immune activation (MIA)/inflammation in congruence with oxidative/nitrosative stress can lead to neurodevelopmental damage and behavioral abnormalities in the offspring. Although the underlying precise mechanistic processes of MIA/inflammation are yet to be completely elucidated, it is being increasingly recognized that Toll-like receptors (TLRs) that form the first line of defense against invading microorganisms could participate in the prenatal infection induced immune insults. Interestingly, some of the TLRs, especially TLR3 and TLR4 that modulate neurodevelopment, neuronal survival and neuronal plasticity by regulating the neuro-immune cross-talk in the developing and adult brain could also be affected by prenatal infection. Importantly, sustained activation of TLR3/TLR4 due to environmental factors including infection and stress has been found to generate excessive reactive oxygen species (ROS)/reactive nitrogen species (RNS) as well as pro-inflammatory mediators during embryogenesis, which result into neuronal damage by necrosis/apoptosis. In recent times, ROS/RNS and immuno-inflammatory mediators are being increasingly linked to progressive brain changes in schizophrenia. Although a significant role of TLR3/TLR4 in neurodegeneration is gaining certainty, their importance in establishing a causal link between prenatal infection and immuno-inflammatory, oxidative and nitrosative stress (IO&NS) responses and influence on adult presentation of schizophrenia is yet to be ascertained. We review here the current knowledge generated from

Coreactant-free and Label-free Eletrochemiluminescence Immunosensor for Copeptin Based on Luminescent Immuno-Gold Nanoassemblys.

Science.gov (United States)

Han, Zhili; Shu, Jiangnan; Jiang, Qiaoshi; Cui, Hua

2018-04-25

In this work, the eletrochemiluminescence (ECL) behavior of Cu 2+ /cysteine complexes and N-(aminobutyl)-N-(ethylisoluminol) (ABEI) functionalized gold nanoparticles combined with chitosan (Cu 2+ -Cys-ABEI-GNPs-CS) were studied by cyclic voltammetry and a double-step potential, which exhibited excellent ECL properties without any coreactant. It was found that the ECL intensity of Cu 2+ -Cys-ABEI-GNPs-CS could increase at least one order of magnitude compared with that of Cu 2+ -Cys-ABEI-GNPs. Furthermore, a coreactant-free and label-free ECL immunosensor has been established for the determination of early acute myocardial infarction biomarker copeptin based on luminescent immuno-gold nanoassemblys consisting of Cu 2+ -Cys-ABEI-GNPs-CS and immuno-gold nanoparticles prepared by connecting copeptin antibody with trisodium citrate stabilized gold nanoparticles. In the presence of copeptin, an obvious decrease in ECL intensity was observed due to the formation of antibody-antigen immunocomplex, which could be used for the determination of copeptin in the range of 2.0×10 -14 -1.0×10 -11 mol/L with a detection limit of 5.18×10 -15 mol/L. The detection limit of the ECL immunosensor is at least two orders of magnitude lower than that of sandwich immunoassays based on labeling technology. And the ECL immunosensor does not need any coreactant, and avoids complicated labeling and purification procedure. It is ultrasensitive, simple, specific and low-cost. This work reveals that the proposed luminescent immuno-gold nanoassemblys are ideal nanointerfaces for the construction of immunosensors. The proposed strategy may be used for the determination of other antigens if corresponding antibodies are available.

Comparative analysis of two rapid diagnostic tests for diagnosis of ...

African Journals Online (AJOL)

This study aims at comparing the diagnostic efficiencies of two commercially available kits for detecting Plasmodium falciparum infection in urine and blood of febrile patients for malaria diagnosis. This was an observational study in which matched blood and urine from symptomatic patients were tested for malaria using two ...

An audit of diagnostic tests performed in medical microbiology, and ...

African Journals Online (AJOL)

Clinical audit is an important tool for reviewing and improving the quality of service in clinical laboratories. This is a three year audit of diagnostic test carried out in Medical Microbiology and Immunology laboratories of University of Maiduguri Teaching Hospital, Maiduguri, Nigeria. The objectives were to document and ...

Standardized evaluation of tumor-infiltrating lymphocytes in breast cancer: results of the ring studies of the international immuno-oncology biomarker working group.

Science.gov (United States)

Denkert, Carsten; Wienert, Stephan; Poterie, Audrey; Loibl, Sibylle; Budczies, Jan; Badve, Sunil; Bago-Horvath, Zsuzsanna; Bane, Anita; Bedri, Shahinaz; Brock, Jane; Chmielik, Ewa; Christgen, Matthias; Colpaert, Cecile; Demaria, Sandra; Van den Eynden, Gert; Floris, Giuseppe; Fox, Stephen B; Gao, Dongxia; Ingold Heppner, Barbara; Kim, S Rim; Kos, Zuzana; Kreipe, Hans H; Lakhani, Sunil R; Penault-Llorca, Frederique; Pruneri, Giancarlo; Radosevic-Robin, Nina; Rimm, David L; Schnitt, Stuart J; Sinn, Bruno V; Sinn, Peter; Sirtaine, Nicolas; O'Toole, Sandra A; Viale, Giuseppe; Van de Vijver, Koen; de Wind, Roland; von Minckwitz, Gunter; Klauschen, Frederick; Untch, Michael; Fasching, Peter A; Reimer, Toralf; Willard-Gallo, Karen; Michiels, Stefan; Loi, Sherene; Salgado, Roberto

2016-10-01

Multiple independent studies have shown that tumor-infiltrating lymphocytes (TIL) are prognostic in breast cancer with potential relevance for response to immune-checkpoint inhibitor therapy. Although many groups are currently evaluating TIL, there is no standardized system for diagnostic applications. This study reports the results of two ring studies investigating TIL conducted by the International Working Group on Immuno-oncology Biomarkers. The study aim was to determine the intraclass correlation coefficient (ICC) for evaluation of TIL by different pathologists. A total of 120 slides were evaluated by a large group of pathologists with a web-based system in ring study 1 and a more advanced software-system in ring study 2 that included an integrated feedback with standardized reference images. The predefined aim for successful ring studies 1 and 2 was an ICC above 0.7 (lower limit of 95% confidence interval (CI)). In ring study 1 the prespecified endpoint was not reached (ICC: 0.70; 95% CI: 0.62-0.78). On the basis of an analysis of sources of variation, we developed a more advanced digital image evaluation system for ring study 2, which improved the ICC to 0.89 (95% CI: 0.85-0.92). The Fleiss' kappa value for international standardization project shows that reproducible evaluation of TIL is feasible in breast cancer. This opens the way for standardized reporting of tumor immunological parameters in clinical studies and diagnostic practice. The software-guided image evaluation approach used in ring study 2 may be of value as a tool for evaluation of TIL in clinical trials and diagnostic practice. The experience gained from this approach might be applicable to the standardization of other diagnostic parameters in histopathology.

Using Meta-Analysis to Inform the Design of Subsequent Studies of Diagnostic Test Accuracy

Science.gov (United States)

Hinchliffe, Sally R.; Crowther, Michael J.; Phillips, Robert S.; Sutton, Alex J.

2013-01-01

An individual diagnostic accuracy study rarely provides enough information to make conclusive recommendations about the accuracy of a diagnostic test; particularly when the study is small. Meta-analysis methods provide a way of combining information from multiple studies, reducing uncertainty in the result and hopefully providing substantial…

The diagnostic accuracy of three rapid diagnostic tests for typhoid fever at Chittagong Medical College Hospital, Chittagong, Bangladesh.

Science.gov (United States)

Maude, Rapeephan R; de Jong, Hanna K; Wijedoru, Lalith; Fukushima, Masako; Ghose, Aniruddha; Samad, Rasheda; Hossain, Mohammed Amir; Karim, Mohammed Rezaul; Faiz, Mohammed Abul; Parry, Christopher M

2015-10-01

To determine the diagnostic accuracy of three rapid diagnostic tests (RDTs) for typhoid fever in febrile hospitalised patients in Bangladesh. Febrile adults and children admitted to Chittagong Medical College Hospital, Bangladesh, were investigated with Bact/Alert(®) blood cultures and real-time PCR to detect Salmonella enterica Typhi and Paratyphi A and assays for Rickettsia, leptospirosis and dengue fever. Acute serum samples were examined with the LifeAssay (LA) Test-it™ Typhoid IgM lateral flow assay detecting IgM antibodies against S. Typhi O antigen, CTKBiotech Onsite Typhoid IgG/IgM Combo Rapid-test cassette lateral flow assay detecting IgG and IgM antibodies against S. Typhi O and H antigens and SD Bioline line assay for IgG and IgM antibodies against S. Typhi proteins. In 300 malaria smear-negative febrile patients [median (IQR) age of 13.5 (5-31) years], 34 (11.3%) had confirmed typhoid fever: 19 positive by blood culture for S. Typhi (three blood PCR positive) and 15 blood culture negative but PCR positive for S. Typhi in blood. The respective sensitivity and specificity of the three RDTs in patients using a composite reference standard of blood culture and/or PCR-confirmed typhoid fever were 59% and 61% for LifeAssay, 59% and 74% for the CTK IgM and/or IgG, and 24% and 96% for the SD Bioline RDT IgM and/or IgG. The LifeAssay RDT had a sensitivity of 63% and a specificity of 91% when modified with a positive cut-off of ≥2+ and analysed using a Bayesian latent class model. These typhoid RDTs demonstrated moderate diagnostic accuracies, and better tests are needed. © 2015 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.

Liquid chromatographic analysis of phenobarbitone, ethosuximide ...

African Journals Online (AJOL)

A liquid chromatographic method for the simultaneous assay of four anticonvulsant drugs, phenobarbitone, ethosuximide, phenytoin and carbamazepine on a polystyrene-divinyl benzene column is described. The method was developed by the systematic study of different types of co-polymer materials, type and ...

Systematic Review of Health Economic Evaluations of Diagnostic Tests in Brazil: How accurate are the results?

Science.gov (United States)

Oliveira, Maria Regina Fernandes; Leandro, Roseli; Decimoni, Tassia Cristina; Rozman, Luciana Martins; Novaes, Hillegonda Maria Dutilh; De Soárez, Patrícia Coelho

2017-08-01

The aim of this study is to identify and characterize the health economic evaluations (HEEs) of diagnostic tests conducted in Brazil, in terms of their adherence to international guidelines for reporting economic studies and specific questions in test accuracy reports. We systematically searched multiple databases, selecting partial and full HEEs of diagnostic tests, published between 1980 and 2013. Two independent reviewers screened articles for relevance and extracted the data. We performed a qualitative narrative synthesis. Forty-three articles were reviewed. The most frequently studied diagnostic tests were laboratory tests (37.2%) and imaging tests (32.6%). Most were non-invasive tests (51.2%) and were performed in the adult population (48.8%). The intended purposes of the technologies evaluated were mostly diagnostic (69.8%), but diagnosis and treatment and screening, diagnosis, and treatment accounted for 25.6% and 4.7%, respectively. Of the reviewed studies, 12.5% described the methods used to estimate the quantities of resources, 33.3% reported the discount rate applied, and 29.2% listed the type of sensitivity analysis performed. Among the 12 cost-effectiveness analyses, only two studies (17%) referred to the application of formal methods to check the quality of the accuracy studies that provided support for the economic model. The existing Brazilian literature on the HEEs of diagnostic tests exhibited reasonably good performance. However, the following points still require improvement: 1) the methods used to estimate resource quantities and unit costs, 2) the discount rate, 3) descriptions of sensitivity analysis methods, 4) reporting of conflicts of interest, 5) evaluations of the quality of the accuracy studies considered in the cost-effectiveness models, and 6) the incorporation of accuracy measures into sensitivity analyses.

LOGICAL CONDITIONS ANALYSIS METHOD FOR DIAGNOSTIC TEST RESULTS DECODING APPLIED TO COMPETENCE ELEMENTS PROFICIENCY

Directory of Open Access Journals (Sweden)

V. I. Freyman

2015-11-01

Full Text Available Subject of Research.Representation features of education results for competence-based educational programs are analyzed. Solution importance of decoding and proficiency estimation for elements and components of discipline parts of competences is shown. The purpose and objectives of research are formulated. Methods. The paper deals with methods of mathematical logic, Boolean algebra, and parametrical analysis of complex diagnostic test results, that controls proficiency of some discipline competence elements. Results. The method of logical conditions analysis is created. It will give the possibility to formulate logical conditions for proficiency determination of each discipline competence element, controlled by complex diagnostic test. Normalized test result is divided into noncrossing zones; a logical condition about controlled elements proficiency is formulated for each of them. Summarized characteristics for test result zones are imposed. An example of logical conditions forming for diagnostic test with preset features is provided. Practical Relevance. The proposed method of logical conditions analysis is applied in the decoding algorithm of proficiency test diagnosis for discipline competence elements. It will give the possibility to automate the search procedure for elements with insufficient proficiency, and is also usable for estimation of education results of a discipline or a component of competence-based educational program.

Towards Modernizing the Characterization of Shock and Detonation Physics Performance via Novel Diagnostics and Tests

Science.gov (United States)

Salyer, Terry

2017-06-01

For the bulk of detonation performance experiments, a fairly basic set of diagnostic techniques has evolved as the standard for acquiring the necessary measurements. Gold standard techniques such as pin switches and streak cameras still produce the high-quality data required, yet much room remains for improvement with regard to ease of use, cost of fielding, breadth of data, and diagnostic versatility. Over the past several years, an alternate set of diagnostics has been under development to replace many of these traditional techniques. Pulse Correlation Reflectometry (PCR) is a capable substitute for pin switches with the advantage of obtaining orders of magnitude more data at a small fraction of the cost and fielding time. Spectrally Encoded Imaging (SEI) can replace most applications of streak camera with the advantage of imaging surfaces through a single optical fiber that are otherwise optically inaccessible. Such diagnostics advance the measurement state of the art, but even further improvements may come through revamping the standardized tests themselves such as the copper cylinder expansion test. At the core of this modernization, the aforementioned diagnostics play a significant role in revamping and improving the standard test suite for the present era. This research was performed under the auspices of the United States Department of Energy.

Empirical evidence of design-related bias in studies of diagnostic tests

NARCIS (Netherlands)

Lijmer, J. G.; Mol, B. W.; Heisterkamp, S.; Bonsel, G. J.; Prins, M. H.; van der Meulen, J. H.; Bossuyt, P. M.

1999-01-01

CONTEXT: The literature contains a large number of potential biases in the evaluation of diagnostic tests. Strict application of appropriate methodological criteria would invalidate the clinical application of most study results. OBJECTIVE: To empirically determine the quantitative effect of study

An Indian test facility to characterise diagnostic neutral beam for ITER

International Nuclear Information System (INIS)

Singh, M.J.; Bandyopadhyay, M.; Rotti, C.; Singh, N.P.; Shah, Sejal; Bansal, G.; Gahlaut, A.; Soni, J.; Lakdawala, H.; Waghela, Harshad; Ahmed, I.; Roopesh, G.; Baruah, U.K.; Chakraborty, A.K.

2011-01-01

The diagnostic neutral beam (DNB) line shall be used to diagnose the He ash content in the D-T phase of the ITER machine using the charge exchange recombination spectroscopy (CXRS). Implementation of a successful DNB at ITER requires several challenges related to the production, neutralization and transport of the neutral beam over path lengths of 20.665 m, to be overcome. The delivery is aided if the above effects are tested prior to onsite commissioning. As DNB is a procurement package for INDIA, an ITER approved Indian test facility, INTF, is under construction at Institute for Plasma Research (IPR), India and is envisaged to be operational in 2015. The timeline for this facility is synchronized with the RADI, ELISE (IPP, Garching), SPIDER (RFX, Padova) in a manner that best utilization of configurational inputs available from them are incorporated in the design. This paper describes the facility in detail and discusses the experiments planned to optimise the beam transmission and testing of the beam line components using various diagnostics.

[The Offer of Medical-Diagnostic Self-Tests on German Language Websites: Results of a Systematic Internet Search].

Science.gov (United States)

Kuecuekbalaban, P; Schmidt, S; Muehlan, H

2018-03-01

The aim of the current study was to provide an overview of medical-diagnostic self-tests which can be purchased without a medical prescription on German language websites. From September 2014 to March 2015, a systematic internet research was conducted with the following search terms: self-test, self-diagnosis, home test, home diagnosis, quick test, rapid test. 513 different self-tests for the diagnostics of 52 diverse diseases or health risks were identified, including chronic diseases (e. g. diabetes, chronic disease of the kidneys, liver, and lungs), sexually transmitted diseases (e. g. HIV, chlamydia, gonorrhea), infectious diseases (e. g. tuberculosis, malaria, Helicobacter pylori), allergies (e. g. house dust, cats, histamine) and cancer as well as tests for the diagnostics of 12 different psychotropic substances. These were sold by 90 companies in Germany and by other foreign companies. The number of medical-diagnostic self-tests which can be bought without a medical prescription on the Internet has increased enormously in the last 10 years. Further studies are needed for the identification of the determinants of the use of self-tests as well as the impact of the application on the experience and behavior of the user. © Georg Thieme Verlag KG Stuttgart · New York.

Estimating diagnostic test accuracies for Brachyspira hyodysenteriae accounting for the complexities of population structure in food animals.

Directory of Open Access Journals (Sweden)

Sonja Hartnack

Full Text Available For swine dysentery, which is caused by Brachyspira hyodysenteriae infection and is an economically important disease in intensive pig production systems worldwide, a perfect or error-free diagnostic test ("gold standard" is not available. In the absence of a gold standard, Bayesian latent class modelling is a well-established methodology for robust diagnostic test evaluation. In contrast to risk factor studies in food animals, where adjustment for within group correlations is both usual and required for good statistical practice, diagnostic test evaluation studies rarely take such clustering aspects into account, which can result in misleading results. The aim of the present study was to estimate test accuracies of a PCR originally designed for use as a confirmatory test, displaying a high diagnostic specificity, and cultural examination for B. hyodysenteriae. This estimation was conducted based on results of 239 samples from 103 herds originating from routine diagnostic sampling. Using Bayesian latent class modelling comprising of a hierarchical beta-binomial approach (which allowed prevalence across individual herds to vary as herd level random effect, robust estimates for the sensitivities of PCR and culture, as well as for the specificity of PCR, were obtained. The estimated diagnostic sensitivity of PCR (95% CI and culture were 73.2% (62.3; 82.9 and 88.6% (74.9; 99.3, respectively. The estimated specificity of the PCR was 96.2% (90.9; 99.8. For test evaluation studies, a Bayesian latent class approach is well suited for addressing the considerable complexities of population structure in food animals.

The contribution of the hydrogen bond acidity on the lipophilicity of drugs estimated from chromatographic measurements.

Science.gov (United States)

Pallicer, Juan M; Pascual, Rosalia; Port, Adriana; Rosés, Martí; Ràfols, Clara; Bosch, Elisabeth

2013-02-14

The influence of the hydrogen bond acidity when the 1-octanol/water partition coefficient (log P(o/w)) of drugs is determined from chromatographic measurements was studied in this work. This influence was firstly evaluated by means of the comparison between the Abraham solvation parameter model when it is applied to express the 1-octanol/water partitioning and the chromatographic retention, expressed as the solute polarity p. Then, several hydrogen bond acidity descriptors were compared in order to determine properly the log P(o/w) of drugs. These descriptors were obtained from different software and comprise two-dimensional parameters such as the calculated Abraham hydrogen bond acidity A and three-dimensional descriptors like HDCA-2 from CODESSA program or WO1 and DRDODO descriptors calculated from Volsurf+software. The additional HOMO-LUMO polarizability descriptor should be added when the three-dimensional descriptors are used to complement the chromatographic retention. The models generated using these descriptors were compared studying the correlations between the determined log P(o/w) values and the reference ones. The comparison showed that there was no significant difference between the tested models and any of them was able to determine the log P(o/w) of drugs from a single chromatographic measurement and the correspondent molecular descriptors terms. However, the model that involved the calculated A descriptor was simpler and it is thus recommended for practical uses. Copyright © 2012 Elsevier B.V. All rights reserved.

On-line gas chromatographic analysis of airborne particles

Science.gov (United States)

Hering, Susanne V [Berkeley, CA; Goldstein, Allen H [Orinda, CA

2012-01-03

A method and apparatus for the in-situ, chemical analysis of an aerosol. The method may include the steps of: collecting an aerosol; thermally desorbing the aerosol into a carrier gas to provide desorbed aerosol material; transporting the desorbed aerosol material onto the head of a gas chromatography column; analyzing the aerosol material using a gas chromatograph, and quantizing the aerosol material as it evolves from the gas chromatography column. The apparatus includes a collection and thermal desorption cell, a gas chromatograph including a gas chromatography column, heated transport lines coupling the cell and the column; and a quantization detector for aerosol material evolving from the gas chromatography column.

Bulletin of Animal Health and Production in Africa - Vol 55, No 4 (2007)

African Journals Online (AJOL)

Prevalence Of Sole Haemorrhages And Its Correlation With Subclinical And Chronic Laminitis In Dairy Cows ... The Distribution Of Bovine Leukemia Virus Genotypes In Cattle From Japan And Diagnostic Performance Of Agar Gel Immuno Diffusion (Agid) And Polymerase Chain Reaction (Pcr) Tests. Y Asfaw, H Sentsui.

Liquid chromatographic-mass spectrometric method for ...

African Journals Online (AJOL)

Tropical Journal of Pharmaceutical Research ... Purpose: To develop and validate a simple, efficient and reliable Liquid chromatographic-mass spectrometric (LC-MS/MS) method for the quantitative determination of two dermatological drugs, ... By Country · List All Titles · Free To Read Titles This Journal is Open Access.

Diagnostic x-ray equipment compliance and facility survey. Recommended procedures for equipment and facility testing

International Nuclear Information System (INIS)

1994-01-01

The Radiation Protection Bureau has set out guidelines for the testing of diagnostic x-ray equipment and facilities. This guide provides information for the x-ray inspector, test engineer, technologist, medical physicist and any other person responsible for verifying the regulatory compliance or safety of diagnostic x-ray equipment and facilities. Diagnostic x-radiation is an essential part of present day medical practice. The largest contributor of irradiation to the general population comes from diagnostic x-radiation. Although individual irradiations are usually small, there is a concern of possible excess cancer risk when large populations are irradiated. Unnecessary irradiations to patients from radiological procedures can be significantly reduced with little or no decrease in the value of medical diagnostic information. This can be achieved by using well designed x-ray equipment which is installed, used and maintained by trained personnel, and by the adoption of standardized procedures. In general, when patient surface dose is reduced, there is a corresponding decrease in dose to x-ray equipment operators and other health care personnel. 2 tabs., 4 figs

Diagnostic x-ray equipment compliance and facility survey. Recommended procedures for equipment and facility testing

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-12-31

The Radiation Protection Bureau has set out guidelines for the testing of diagnostic x-ray equipment and facilities. This guide provides information for the x-ray inspector, test engineer, technologist, medical physicist and any other person responsible for verifying the regulatory compliance or safety of diagnostic x-ray equipment and facilities. Diagnostic x-radiation is an essential part of present day medical practice. The largest contributor of irradiation to the general population comes from diagnostic x-radiation. Although individual irradiations are usually small, there is a concern of possible excess cancer risk when large populations are irradiated. Unnecessary irradiations to patients from radiological procedures can be significantly reduced with little or no decrease in the value of medical diagnostic information. This can be achieved by using well designed x-ray equipment which is installed, used and maintained by trained personnel, and by the adoption of standardized procedures. In general, when patient surface dose is reduced, there is a corresponding decrease in dose to x-ray equipment operators and other health care personnel. 2 tabs., 4 figs.

[Critical reading of articles about diagnostic tests (part I): Are the results of the study valid?].

Science.gov (United States)

Arana, E

2015-01-01

In the era of evidence-based medicine, one of the most important skills a radiologist should have is the ability to analyze the diagnostic literature critically. This tutorial aims to present guidelines for determining whether primary diagnostic articles are valid for clinical practice. The following elements should be evaluated: whether the study can be applied to clinical practice, whether the technique was compared to the reference test, whether an appropriate spectrum of patients was included, whether expectation bias and verification bias were limited, the reproducibility of the study, the practical consequences of the study, the confidence intervals for the parameters analyzed, the normal range for continuous variables, and the placement of the test in the context of other diagnostic tests. We use elementary practical examples to illustrate how to select and interpret the literature on diagnostic imaging and specific references to provide more details. Copyright © 2014 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

A hybrid model for combining case-control and cohort studies in systematic reviews of diagnostic tests

Science.gov (United States)

Chen, Yong; Liu, Yulun; Ning, Jing; Cormier, Janice; Chu, Haitao

2014-01-01

Systematic reviews of diagnostic tests often involve a mixture of case-control and cohort studies. The standard methods for evaluating diagnostic accuracy only focus on sensitivity and specificity and ignore the information on disease prevalence contained in cohort studies. Consequently, such methods cannot provide estimates of measures related to disease prevalence, such as population averaged or overall positive and negative predictive values, which reflect the clinical utility of a diagnostic test. In this paper, we propose a hybrid approach that jointly models the disease prevalence along with the diagnostic test sensitivity and specificity in cohort studies, and the sensitivity and specificity in case-control studies. In order to overcome the potential computational difficulties in the standard full likelihood inference of the proposed hybrid model, we propose an alternative inference procedure based on the composite likelihood. Such composite likelihood based inference does not suffer computational problems and maintains high relative efficiency. In addition, it is more robust to model mis-specifications compared to the standard full likelihood inference. We apply our approach to a review of the performance of contemporary diagnostic imaging modalities for detecting metastases in patients with melanoma. PMID:25897179

Beam diagnostic tools for the negative hydrogen ion source test facility ELISE

International Nuclear Information System (INIS)

Nocentini, Riccardo; Fantz, Ursel; Franzen, Peter; Froeschle, Markus; Heinemann, Bernd; Riedl, Rudolf; Ruf, Benjamin; Wuenderlich, Dirk

2013-01-01

Highlights: ► We present an overview of beam diagnostic tools foreseen for the new testbed ELISE. ► A sophisticated diagnostic calorimeter allows beam profile measurement. ► A tungsten wire mesh in the beam path provides a qualitative picture of the beam. ► Stripping losses and beam divergence are measured by H α Doppler shift spectroscopy. -- Abstract: The test facility ELISE, presently being commissioned at IPP, is a first step in the R and D roadmap for the RF driven ion source and extraction system of the ITER NBI system. The “half-size” ITER-like test facility includes a negative hydrogen ion source that can be operated for 1 h. ELISE is expected to extract an ion beam of 20 A at 60 kV for 10 s every 3 min, therefore delivering a total power of 1.2 MW. The extraction area has a geometry that closely reproduces the ITER design, with the same width and half the height, i.e. 1 m × 1 m. This paper presents an overview of beam diagnostic tools foreseen for ELISE. For the commissioning phase, a simple beam dump with basic diagnostic capabilities has been installed. In the second phase, the beam dump will be substituted by a more sophisticated diagnostic calorimeter to allow beam profile measurement. Additionally, a tungsten wire mesh will be introduced in the beam path to provide a qualitative picture of beam size and position. Stripping losses and beam divergence will be measured by means of H α Doppler shift spectroscopy. An absolute calibration is foreseen in order to measure beam intensity

Analysis and chromatographic purification of eicosanoids multiply labeled by tritium

International Nuclear Information System (INIS)

Shevchenko, V.P.; Nagaev, I.Yu.; Myasoedov, N.F.

1989-01-01

We show the possibility of analysis and chromatographic purification of eicosanoids triply labeled by tritium. The described methods allow us to isolate chromatographically pure products obtained by selective hydrogenatin, chemical, and enzyme methods, with radiochemical purity at least 95-97%. The following methods are used to analyze the reaction mixtures and to isolate the tritium-labeled eicosanoids: gas-liquid chromatography, high-efficiency liquid chromatography, and thin-layer chromatography on supports impregnated with silver nitrate

Interlaboratory comparison and accreditation in quality control testing of diagnostic X-ray equipment

International Nuclear Information System (INIS)

Kepler, K.; Vladimirov, A.; Servomaa, A.

2005-01-01

The Univ. of Tartu provides a quality control service to the majority of diagnostic X-ray departments in Estonia. Its methodology has been adopted from the IEC and other relevant standards. Recently the Testing Centre of the Univ. of Tartu was accredited on this methodology by ISO/IEC 17025. Besides the implementation of the quality management system, participation in interlaboratory comparison (ILC) was one of the prerequisites for the accreditation. Tests for estimating reproducibility of tube voltage and dose rate, accuracy of the voltage and accuracy of exposure time were carried out on a diagnostic X-ray unit in the Radiation and Nuclear Safety Authority in Helsinki. The measurement performance was judged by calculating deviation En normalised with respect to the stated uncertainties. En values for all tests were less than unity and by the common ILC criteria the testing performance could be considered as acceptable. (authors)

Translating microarray data for diagnostic testing in childhood leukaemia

International Nuclear Information System (INIS)

Hoffmann, Katrin; Firth, Martin J; Beesley, Alex H; Klerk, Nicholas H de; Kees, Ursula R

2006-01-01

Recent findings from microarray studies have raised the prospect of a standardized diagnostic gene expression platform to enhance accurate diagnosis and risk stratification in paediatric acute lymphoblastic leukaemia (ALL). However, the robustness as well as the format for such a diagnostic test remains to be determined. As a step towards clinical application of these findings, we have systematically analyzed a published ALL microarray data set using Robust Multi-array Analysis (RMA) and Random Forest (RF). We examined published microarray data from 104 ALL patients specimens, that represent six different subgroups defined by cytogenetic features and immunophenotypes. Using the decision-tree based supervised learning algorithm Random Forest (RF), we determined a small set of genes for optimal subgroup distinction and subsequently validated their predictive power in an independent patient cohort. We achieved very high overall ALL subgroup prediction accuracies of about 98%, and were able to verify the robustness of these genes in an independent panel of 68 specimens obtained from a different institution and processed in a different laboratory. Our study established that the selection of discriminating genes is strongly dependent on the analysis method. This may have profound implications for clinical use, particularly when the classifier is reduced to a small set of genes. We have demonstrated that as few as 26 genes yield accurate class prediction and importantly, almost 70% of these genes have not been previously identified as essential for class distinction of the six ALL subgroups. Our finding supports the feasibility of qRT-PCR technology for standardized diagnostic testing in paediatric ALL and should, in conjunction with conventional cytogenetics lead to a more accurate classification of the disease. In addition, we have demonstrated that microarray findings from one study can be confirmed in an independent study, using an entirely independent patient cohort

The psychological impact of test results following diagnostic coronary CT angiography.

Science.gov (United States)

Devcich, Daniel A; Ellis, Christopher J; Broadbent, Elizabeth; Gamble, Greg; Petrie, Keith J

2012-11-01

Coronary computed tomography (CT) angiography is an advanced cardiac imaging test commonly used for diagnosing early signs of ischemic heart disease. Despite its importance in cardiology, little is known about its psychological effect on patients. The present study sought to examine these effects in relation to illness perceptions, cardiac health behavior intentions, and subsequent health behaviors. Forty-five nonacute cardiac patients who were referred for diagnostic coronary CT angiography completed questionnaires prior to testing and following the receipt of test results, at which point illness perceptions and intentions to take cardiac medication, as well as diet and exercise intentions were measured. Exercise and dietary behaviors were measured at follow-up 6 weeks later. Changes on these variables were then compared between patients diagnosed with normal arteries and patients diagnosed with diseased arteries. Compared to positive-testing patients, patients with normal test results reported significant changes toward more positive illness perceptions following testing, with improvements in emotional effect of illness, illness concern, consequences, and personal control of illness. The illness perception of treatment control was seen as more important among positive-testing patients, whereas both groups reported increases in illness coherence. Health behavior intentions (cardiac medication intentions and exercise intentions) increased for positive-testing patients only, as did physical activity at follow-up. Diagnosis-dependent psychological effects can be detected following coronary CT angiography. These effects have important implications for patient health and health care in diagnostic contexts, and the results from this study can be used to guide further research in this area.

Diagnostic accuracy and optimal use of three tests for tuberculosis in live badgers.

Directory of Open Access Journals (Sweden)

Julian A Drewe

Full Text Available BACKGROUND: Accurate diagnosis of tuberculosis (TB due to infection with Mycobacterium bovis is notoriously difficult in live animals, yet important if we are to understand the epidemiology of TB and devise effective strategies to limit its spread. Currently available tests for diagnosing TB in live Eurasian badgers (Meles meles remain unvalidated against a reliable gold standard. The aim of the present study was to evaluate the diagnostic accuracy and optimal use of three tests for TB in badgers in the absence of a gold standard. METHODOLOGY/PRINCIPAL FINDINGS: A Bayesian approach was used to evaluate the diagnostic accuracy and optimal use of mycobacterial culture, gamma-interferon assay and a commercially available serological test using multiple samples collected from 305 live wild badgers. Although no single test was judged to be sufficiently sensitive and specific to be used as a sole diagnostic method, selective combined use of the three tests allowed guidelines to be formulated that allow a diagnosis to be made for individual animals with an estimated overall accuracy of 93% (range: 75% to 97%. Employing this approach in the study population of badgers resulted in approximately 13 out of 14 animals having their true infection status correctly classified from samples collected on a single capture. CONCLUSIONS/SIGNIFICANCE: This method of interpretation represents a marked improvement on the current procedure for diagnosing M. bovis infection in live badgers. The results should be of use to inform future test and intervention strategies with the aim of reducing the incidence of TB in free-living wild badger populations.

Isotope separations using chromatographic methods

International Nuclear Information System (INIS)

Leseticky, L.

1985-01-01

A survey is given of chromatographic separations of compounds only differing in isotope composition. Isotope effects on physical properties which allow chromatographic separation (vapour tension, adsorption heat, partition coefficient) are very small, with the exception of the simplest molecules. Therefore, separation factors only assume the value of several per cent. From this ensues the necessity of using columns which are specially and very carefully prepared and have a separation efficiency of the order of 10 4 theoretical plates. Briefly discussed is liquid chromatography on ion exchangers which with a varied degree of success was used for separating simple inorganic compounds or ions. Ion exchange chromatography of amino acids labelled with tritium, and chromatography of tritium labelled steroids also provided only a certain degree of separation. A detailed analysis is presented of gas chromatography separation of various deuterium and tritium labelled low-molecular compounds, to which a number of studies has been devoted in the literature. Very promising is the method of complexation gas chromatography based on the reversible formation of a complex of the ligand (the compound being separated) and the compound of the (transition) metal as the steady-state phase. (author)

Consensus based reporting standards for diagnostic test accuracy studies for paratuberculosis in ruminants.

NARCIS (Netherlands)

Gardner, I.A.; Nielsen, S.S.; Whittington, R.J.; Collins, M.T.; Bakker, D.; Harris, B.; Sreevatsan, S.; Lombard, J.E.; Sweeney, R.; Smith, D.R.; Gavalchin, J.; Eda, S.

2011-01-01

The Standards for Reporting of Diagnostic Accuracy (STARD) statement (www.stard-statement.org) was developed to encourage complete and transparent reporting of key elements of test accuracy studies in human medicine. The statement was motivated by widespread evidence of bias in test accuracy studies

Chromatographic monitoring procedures in laboratory practice

Energy Technology Data Exchange (ETDEWEB)

Kaplina, E G; Belova, O I; Lasunina, N A

1976-01-01

The Moscow Coke and Chemical Works consist of three plants in combination, viz., the coking plant, the synthetic ammonia plant using coke-oven-gas hydrogen and the oxygen plant. The plant requirements include daily analyses not only of the coke-oven gas but also of a rich gas and an ethylene fraction. The analyses are carried out in VTI-2 apparatus. The analytical data are used to calculate the calorific values and densities of the gases. The time requirements are very considerable and the laboratory has long been engaged in developing and introducing chromatographic procedures for the major constituents of coke-oven gas, rich gas and ethylene fraction. The procedure developed for the coke-oven and rich gases uses two parallel columns, one packed with molecular sieves and the other with grade KSM silica gel. Hydrogen was determined with argon as the carrier gas, and all other constituents with helium. The procedure was time-consuming and complicated. An attempt was made to separate the gases in an LKhM-7a chromatograph with a programme-controlled 50 to 250/sup 0/C heating cycle, but the procedure still had a number of serious defects and could not be recommended for regular quality control. The final variant involved two parallel columns and a procedure based on that in GOST 14920 (''Dry gas. Proximate analysis''). The chromatograph was a type KhL-69 with a 6-way cock in the gas line so that each of the columns could be brought on stream in succession. The analytical column packings were zeolite (in a 2 m column) and diatomaceous brick with 25% n-hexadecane (in a 6 m column).

Diagnostic tests for Helicobacter pylori : A prospective evaluation of their accuracy, without selecting a single test as the gold standard

NARCIS (Netherlands)

Thijs, J C; van Zwet, A A; Thijs, W J; Oey, H B; Karrenbeld, A; Stellaard, F; Luijt, D S; Meyer, B C; Kleibeuker, J H

1996-01-01

OBJECTIVE: To assess the accuracy of six commonly used diagnostic tests for Helicobacter pylori in a prospective study without using any specific test as the gold standard (the patient was regarded as H. pylori-infected if two or more tests, whatever their nature, were positive). METHODS: In 105

Annotating STEAP1 regulation in prostate cancer with 89Zr immuno-PET.

Science.gov (United States)

Doran, Michael G; Watson, Philip A; Cheal, Sarah M; Spratt, Daniel E; Wongvipat, John; Steckler, Jeffrey M; Carrasquillo, Jorge A; Evans, Michael J; Lewis, Jason S

2014-12-01

Antibodies and antibody-drug conjugates targeting the cell surface protein 6 transmembrane epithelial antigen of prostate 1 (STEAP1) are in early clinical development for the treatment of castration-resistant prostate cancer (PCa). In general, antigen expression directly affects the bioactivity of therapeutic antibodies, and the biologic regulation of STEAP1 is unusually complicated in PCa. Paradoxically, STEAP1 can be induced or repressed by the androgen receptor (AR) in different human PCa models, while also expressed in AR-null PCa. Consequently, there is an urgent need to translate diagnostic strategies to establish which regulatory mechanism predominates in patients to situate the appropriate therapy within standard of care therapies inhibiting AR. To this end, we prepared and evaluated (89)Zr-labeled MSTP2109A ((89)Zr-2109A), a radiotracer for PET derived from a fully humanized monoclonal antibody to STEAP1 in preclinical PCa models. (89)Zr-2109A specifically localized to the STEAP1-positive human PCa models CWR22Pc, 22Rv1, and PC3. Moreover, (89)Zr-2109A sensitively measured treatment-induced changes (∼66% decline) in STEAP1 expression in CWR22PC in vitro and in vivo, a model we showed to express STEAP1 in an AR-dependent manner. These findings highlight the ability of immuno-PET with (89)Zr-2109A to detect acute changes in STEAP1 expression and argue for an expansion of ongoing efforts to image PCa patients with (89)Zr-2109A to maximize the clinical benefit associated with antibodies or antibody-drug conjugates to STEAP1. © 2014 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Use of coextraction and suppression of extraction in extraction-chromatographic separation of elements

International Nuclear Information System (INIS)

Karandashev, V.K.; Kuznetsov, R.A.; Grazhulene, S.S.; Usmanova, M.M.

1988-01-01

TBP, solutions of hydrobromic acid, indium and polytetrafluoroethylene powder, carrier for TBP, were used to study the effects of coextraction and extraction suppression on extraction-chromatographic behaviour of microamounts of elements in the presence of macroamounts of other elements. Possibility of using these effects under extraction-chromatographic element separation were considered. A new method for extraction-chromatographic separation of scandium microamounts from the mixture of large amount of elements (Y, Cd, Ce, Eu, Lu, Hf, Ta, W, Np and other) was suggested. 15 refs.; 3 figs

Continuous-data diagnostic tests for paratuberculosis as a multistage disease

DEFF Research Database (Denmark)

Toft, Nils; Nielsen, Søren Saxmose; Jørgensen, Erik

2005-01-01

We devised a general method for interpretation of multistage diseases using continuous-data diagnostic tests. As an example, we used paratuberculosis as a multistage infection with 2 stages of infection as well as a noninfected state. Using data from a Danish research project, a fecal culture...... testing scheme was linked to an indirect ELISA and adjusted for covariates (parity, age at first calving, and days in milk). We used the log-transformed optical densities in a Bayesian network to obtain the probabilities for each of the 3 infection stages for a given optical density (adjusted...... for covariates). The strength of this approach was that the uncertainty associated with a test was imposed directly on the individual test result rather than aggregated into the population-based measures of test properties (i.e., sensitivity and specificity)...

Ion Chromatographic Analyses of Sea Waters, Brines and Related Samples

OpenAIRE

Nataša Gros

2013-01-01

This review focuses on the ion chromatographic methods for the analyses of natural waters with high ionic strength. At the beginning a natural diversity in ionic composition of waters is highlighted and terminology clarified. In continuation a brief overview of other review articles of potential interest is given. A review of ion chromatographic methods is organized in four sections. The first section comprises articles focused on the determination of ionic composition of water samples as com...

The diagnostic effects of s-TSH and TRH stimulating test on subclinical thyroid function

International Nuclear Information System (INIS)

Lu Shujun; Wang Wenliang; Lu Shuyan; Zheng Linong; Hu Changjun; Fang Xiaozheng; Zheng Huian; Ma Meizhen

2002-01-01

The study was carried out to investigate the diagnostic effects of supersensitive TSH on diagnosing subclinical thyroid function with only once s-TSH detection and with TRH stimulating tests. TRH stimulating tests have been undertaken for 90 patients with different thyroid disease and 58 normal subjects. Diagnostic basal levels of s-TSH test in control group, subclinical hyperthyroidism group and subclinical hypothyroidism group were 2.20 +- 1.85 mIU/L, 0.54 +- 0.3 mIU/L and 9.08 +- 6.3 mIU/L, respectively, the levels of subclinical hyperthyroidism and subclinical hypothyroidism group were significantly higher than that of normal subjects group (P s -TSH>30 mIU/L. Dynamic observing of TRH stimulating tests have more effect than that of only once s-TSH detection in diagnosing subclinical thyroid function

[Research on the application of grey system theory in the pattern recognition for chromatographic fingerprints of traditional Chinese medicine].

Science.gov (United States)

Wei, Hang; Lin, Li; Zhang, Yuan; Wang, Lianjing; Chen, Qinqun

2013-02-01

A model based on grey system theory was proposed for pattern recognition in chromatographic fingerprints (CF) of traditional Chinese medicine (TCM). The grey relational grade among the data series of each testing CF and the ideal CF was obtained by entropy and norm respectively, then the principle of "maximal matching degree" was introduced to make judgments, so as to achieve the purpose of variety identification and quality evaluation. A satisfactory result in the high performance liquid chromatographic (HPLC) analysis of 56 batches of different varieties of Exocarpium Citrus Grandis was achieved with this model. The errors in the chromatographic fingerprint analysis caused by traditional similarity method or grey correlation method were overcome, as the samples of Citrus grandis 'Tomentosa' and Citrus grandis (L.) Osbeck were correctly distinguished in the experiment. Furthermore in the study on the variety identification of Citrus grandis 'Tomentosa', the recognition rates were up to 92.85%, although the types and the contents of the chemical compositions of the samples were very close. At the same time, the model had the merits of low computation complexity and easy operation by computer programming. The research indicated that the grey system theory has good applicability to pattern recognition in the chromatographic fingerprints of TCM.

Studies on Chromatographic Fingerprint and Fingerprinting Profile-Efficacy Relationship of Polygoni Perfoliati Herba

Directory of Open Access Journals (Sweden)

Li Tian

2013-01-01

Full Text Available Polygoni Perfoliati Herba is widely used in China with antibacterium, anti-inflammatory, expectorant, antitumor, and antivirus activities. To reveal the mechanisms of the activities of Polygoni Perfoliati Herba, the relationship between the fingerprinting profile and its bioactivities was investigated. In the present study, high-performance liquid chromatographic (HPLC fingerprinting method was developed. The established method was applied to analyze 51 batches of Polygoni Perfoliati Herba samples collected from different locations or in different harvesting times in China. Chemometrics, including similarity analysis, hierarchical clustering analysis, and principal component analysis, were used to express their similarities. It was found that similarity values of the samples were in the range of 0.432–0.998. The results of analgesic tests indicated that Polygoni Perfoliati Herba could significantly inhibit pain induced by hot plate and acetic acid in mice. The results of anti-inflammatory tests showed that Polygoni Perfoliati Herba had good anti-inflammatory effects (P < 0.01 in two models including dimethyl benzene-induced ear edema and acetic acid-induced peritoneal permeability in mice. Combining the results from chromatographic fingerprints with those from bioactivities, we found that seven peaks from Polygoni Perfoliati Herba were mainly responsible for analgesic and anti-inflammatory activities.

Protease activity measurement in milk as a diagnostic test for clinical mastitis in dairy cows

NARCIS (Netherlands)

Koop, G.; van Werven, T.; Roffel, S.; Hogeveen, H.; Nazmi, K.; Bikker, F.J.

2015-01-01

Due to the increasing use of automated milking systems, automated detection of clinical mastitis is becoming more important. Various in- or on-line diagnostic tests are in use, but generally suffer from false mastitis alerts. In this study, we explored a new diagnostic approach based on measurement

The furosemide diagnostic test in suspected slow-onset heart failure : popular but not useful

NARCIS (Netherlands)

Kelder, Johannes C.; Cramer, Maarten J.; Rutten, Frans H.; Plokker, H. W.; Grobbee, Diederick E.; Hoes, Arno W.

Aims Early, slow-onset heart failure is difficult to diagnose from just signs and symptoms. The physician needs ancillary diagnostic tests. The 'loop-diuretic test' or 'furosemide test', characterized as weight loss and alleviation of symptoms after a short course of a loop-diuretic, could be a

The counterintuitive role of extra-column volume in the determination of column efficiency and scaling of chromatographic processes

NARCIS (Netherlands)

Schultze-Jena, A.; Boon, M.A.; Bussmann, P.J.Th.; Janssen, A.E.M.; Padt, van der A.

2017-01-01

In industrial liquid separation processes chromatography often has a key function in the optimization of yield and purity. For the design of an industrial system, chromatographic processes are generally simulated using mathematical models, tested and optimized at laboratory level, and then scaled

The counterintuitive role of extra-column volume in the determination of column efficiency and scaling of chromatographic processes

NARCIS (Netherlands)

Schultze-Jena, A.; Boon, M.A.; Bussmann, P.J.T.; Janssen, A.E.M.; Padt, A. van der

2017-01-01

In industrial liquid separation processes chromatography often has a key function in the optimization of yield and purity. For the design of an industrial system, chromatographic processes are generally simulated using mathematical models, tested and optimized at laboratory level, and then scaled up

High-performance liquid-chromatographic separation of subcomponents of antimycin-A

Science.gov (United States)

Abidi, S.L.

1988-01-01

Using a reversed-phase high-performance liquid chromatographic (HPLC) technique, a mixture of antimycins A was separated into eight hitherto unreported subcomponents, Ala, Alb, A2a, A2b, A3a, A3b, A4a, and A4b. Although a base-line resolution of the known four major antimycins Al, A2, A3, and A4 was readily achieved with mobile phases containing acetate buffers, the separation of the new antibiotic subcomponents was highly sensitive to variation in mobile phase conditions. The type and composition of organic modifiers, the nature of buffer salts, and the concentration of added electrolytes had profound effects on capacity factors, separation factors, and peak resolution values. Of the numerous chromatographic systems examined, a mobile phase consisting of methanol-water (70:30) and 0.005 M tetrabutylammonium phosphate at pH 3.0 yielded the most satisfactory results for the separation of the subcomponents. Reversed-phase gradient HPLC separation of the dansylated or methylated antibiotic compounds produced superior chromatographic characteristics and the presence of added electrolytes was not a critical factor for achieving separation. Differences in the chromatographic outcome between homologous and structural isomers were interpretated based on a differential solvophobic interaction rationale. Preparative reversed-phase HPLC under optimal conditions enabled isolation of pure samples of the methylated antimycin subcomponents for use in structural studies.

Structured approach to design of diagnostic test evaluation studies for chronic progressive infections in animals

DEFF Research Database (Denmark)

Nielsen, Søren Saxmose; Toft, Nils; Gardner, Ian Andrew

2011-01-01

Diagnostic test evaluations (DTEs) for chronic infections are challenging because a protracted incubation period has to be considered in the design of the DTE, and the adverse effects of infection may be widespread and progressive over an animal's entire life. Frequently, the specific purpose......) than originally intended. The objective of this paper is to outline a structured approach to the design and conduct of a DTE for diagnostic tests used for chronic infections in animals, and intended for different purposes. We describe the process from reflections about test purpose and the underlying...... of the test is not formally considered when a test is evaluated. Therefore, the result is often a DTE where test sensitivity and specificity estimates are biased, either because of problems with establishing the true infection status or because the test detects another aspect of the infection (and analyte...

Chromatographic decontamination of medium-activity waste concentrates

International Nuclear Information System (INIS)

Faubel, W.; Menzler, P.M.; Sameh, A.A.

1988-01-01

The chromatographic decontamination of a MAW concentrate was carried out in a laboratory plant in 1-l-batches in the following way: In order to purify the nitric MAW concentrate from its solid and organic contamination products, it is passed through a filter and an absorber (SM7) for organic species. Subsequently the purified solution runs on-line through all following columns. First the main activity carrier cesium ( 137 Cs, 134 Cs) is transferred to ammonium molybdate phosphate (AMP-1) by means of a newly developed fluidized bed process. In the further course, 125 Sb is separated on metal oxides (Sb 2 O 5 , MnO 2 ) and the three-valued actinides/lanthanides on an extraction-chromatographic CMPO column. Finally the remaining 106 Ru and 60 Co activities are separated on dimethylglyoximes (DMG) coated on active carbon. (orig./RB) [de

Diagnostic Tests for The Control of Foot and Mouth Disease: An ...

African Journals Online (AJOL)

This paper describes the various diagnostic tests available for FMD, the limitations of each and their potential application in a low technology setting. The need to have complementary field and laboratory operations including suitable samples and transport methods are discussed, and examples are given. The importance of ...

Applications of optical fibers in nuclear test diagnostics

International Nuclear Information System (INIS)

Lyons, P.B.; Hodson, E.K.; Looney, L.D.

1980-01-01

Two new plasma diagnostic experiments have been successfully fielded on nuclear device tests at NTS. Both systems rely on the unique advantages provided by optical fiber technology and both systems provide new diagnostic capabilities that previously were beyond the state-of-the-art in coaxial cable systems. One system addresses the need to record e wide bandwidth data on gamma-ray sources. Over the long (< 1 km) distances that characterize NTS testing, the bandwidth of coaxial cable systems is usually limited to < 200 to 400 MHz even with extensive equalization. The new system uses the Cerenkov process to generate light in a converter material. High bandwidth fibers and detectors are used to approach a 1-GHz bandwidth. In this case fibers provided the bandwidth capability. The second system provides time and space resolution of a neutron source on a fast (ns) time scale. Previous systems have utilized either an array of neutron detectors with individual coaxial cables or a fast scintillator viewed by a gated image intensifier. For a large number of channels, the coaxial system becomes very costly and is subject to potentially severe EMI concerns. The gated intensifier system requires complex electronics and accurate timing and can be affected by EMI. An alternative system is described which provides continuous time coverage with limited spatial resolution. Complete freedom from EMI is achieved through the use of optical data collection and transmission. The optical fibers offered a major (2 to 3 times) cost savings and a large weight savings relative to the coax system. Each system is discussed

The introduction of compulsory compliance testing of medical diagnostic x-ray equipment in Western Australia

International Nuclear Information System (INIS)

Rafferty, M. W.; Jacob, C. S.

1995-01-01

Performance testing of medical diagnostic X-ray equipment can reveal equipment faults which, while not always clinically detectable, may contribute to reduced image quality and unnecessary radiation exposure of both patients and staff. Routine testing of such equipment is highly desirable to identify such faults and allows them to be rectified. The Radiological council of Western Australia is moving towards requiring compulsory compliance testing of all (new and existing) medical diagnostic X-ray equipment that all new mobile radiographic and new mammographic X-ray equipment be issued with a compliance test certificate as a prerequisite for registration. Workbooks which provide details of the tests required and recommended test methods have been prepared for medical radiographic (mobile and fixed), fluoroscopic and mammographic X-ray equipment. It is intended that future workbooks include details of the tests and methods for dental and computed tomography X-ray units. The workbooks are not limited to the compliance testing of items as specified in the Regulations, but include tests for other items such as film processing, darkrooms and image quality (for fluoroscopic equipment). Many of the workbook tests could be used within a regular quality assurance program for diagnostic X-ray equipment. Persons who conduct such compliance tests will need to be licensed and have all test certificates endorsed by a qualified expert. Suitable training and assessment of compliance testers will be required. Notification of such tests (including non-compliant items and corrective actions taken) will be required by the Radiological Council as a condition of equipment registration. 9 refs

Pearls and pitfalls of allergy diagnostic testing: report from the American College of Allergy, Asthma and Immunology/American Academy of Allergy, Asthma and Immunology Specific IgE Test Task Force.

Science.gov (United States)

Cox, Linda; Williams, Brock; Sicherer, Scott; Oppenheimer, John; Sher, Larry; Hamilton, Robert; Golden, David

2008-12-01

The intended purpose of this monograph is to provide a general overview of allergy diagnostics for health care professionals who care for patients with allergic disease. For a more comprehensive review of allergy diagnostic testing, readers can refer to the Allergy Diagnostic Practice Parameters. A key message is that a positive allergy test result (skin or blood) indicates only the presence of allergen specific IgE (called sensitization). It does not necessarily mean clinical allergy (ie, allergic symptoms with exposure). It is important for this reason that the allergy evaluation be based on the patient's history and directed by a health care professional with sufficient understanding of allergy diagnostic testing to use the information obtained from his/her evaluation of the patient to determine (1) what allergy diagnostic tests to order, (2) how to interpret the allergy diagnostic test results, and (3) how to use the information obtained from the allergy evaluation to develop an appropriate therapeutic treatment plan.

42 CFR 415.180 - Teaching setting requirements for the interpretation of diagnostic radiology and other diagnostic...

Science.gov (United States)

2010-10-01

... interpretation of diagnostic radiology and other diagnostic tests. 415.180 Section 415.180 Public Health CENTERS... for the interpretation of diagnostic radiology and other diagnostic tests. (a) General rule. Physician fee schedule payment is made for the interpretation of diagnostic radiology and other diagnostic tests...

[Pilot tests using molecular diagnostic assay cervicovaginal infection during pregnancy].

Science.gov (United States)

Beltrán-Montoya, J; Escudero-Gontes, S; Martínez-Huerta, N E; Ávila-Vergara, M A; Morales-Hernández, V; Canchola-Sotelo, C; Palacios-González, B; Vadillo-Ortega, F

2016-08-01

The prevalence of cervicovaginal infections during pregnancy has been associated with adverse perinatal outcomes however, the actual approach used for diagnosis is not effective. The aim of this study was to compare the diagnosis of vaginal infections in pregnant women using clinical, molecular diagnostic and traditional microbiological culture in a pilot study, to determine the prevalence and association with the development of preterm labor. We performed a nested cross-sectional study composed by 54 women in a cohort of pregnant women in Mexico City. Cervicovaginal infections were evaluated by clinical methods, microbiology culture and a commercially available molecular biology test. Prevalence of cervicovaginal infections during pregnancy was estimated between 28% and 50% according to methodologies. Considering the clinical diagnosis of preterm labor as the gold standard, all diagnostic tests were poor as predictors of preterm labor. Traditional approaches to establish the significance of cervicovaginal infection in pregnancy are exhausted, so be sought new ways to understand this complex relationship. Meanwhile it is recommended to continue to use traditional methods to identify infections during pregnancy in both knowledge of new methods aimed at understanding these relationships are sophisticated.

[Joint diagnostic value of four temperature sensation tests in elderly patients with type 2 diabetic peripheral neuropathy].

Science.gov (United States)

Guo, Wei; Li, Yun-Ming; Ai, Zhi-Hua; You, Zhi-Qing; Wan, Yong; Cheng, Ying; Lang, Hong-Mei

2013-07-01

To explore the joint diagnostic value of four temperature sensation tests in elderly patients with type 2 diabetic peripheral neuropathy. Thermal sensory analyzer-II were applied to measure cool sensation (CS), warm sensation (WS), cold pain sensation (CP)and heat pain sensation (HP) of 308 elderly patients with type 2 diabetes. Logistic regression model was adopted to create the new variable Temp4 from four temperature sensation tests to diagnose type 2 diabetic peripheral neuropathy. The ROC curve analysis was used to determine the best cut-off points of the four temperature sensation and Temp4, and the diagnostic value of it was evaluated. The means of temperature sensation tests of the diabetic peripheral neuropathy (DPN) group were significantly different from those of the non-DPN group (P sensation tests to diagnose the DPN, the sensitivity of WS test was the highest, and the value was 0.710; but the specificity, positive predictive value, negative predictive value, Youden index, diagnostic accuracy and Kappa value of cold sensation test were the highest, and the values were 0.842, 0.746, 0.799, 0.528, 77.92% and 0.535, respectively; the Kappa values of the other three temperature sensation tests were all greater than 0.4 (P sensation tests (P sensation quantitative tests were in good agreementand could be applied to diagnose DPN; the new variable Temp4 could be used for diagnosis of DPN with a higher diagnostic accuracy.

Review: Diagnostic accuracy of PCR-based detection tests for Helicobacter Pylori in stool samples.

Science.gov (United States)

Khadangi, Fatemeh; Yassi, Maryam; Kerachian, Mohammad Amin

2017-12-01

Although different methods have been established to detect Helicobacter pylori (H. pylori) infection, identifying infected patients is an ongoing challenge. The aim of this meta-analysis was to provide pooled diagnostic accuracy measures for stool PCR test in the diagnosis of H. pylori infection. In this study, a systematic review and meta-analysis were carried out on various sources, including MEDLINE, Web of Sciences, and the Cochrane Library from April 1, 1999, to May 1, 2016. This meta-analysis adheres to the guidelines provided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses report (PRISMA Statement). The clinical value of DNA stool PCR test was based on the pooled false positive, false negative, true positive, and true negative of different genes. Twenty-six of 328 studies identified met the eligibility criteria. Stool PCR test had a performance of 71% (95% CI: 68-73) sensitivity, 96% (95% CI: 94-97) specificity, and 65.6 (95% CI: 30.2-142.5) diagnostic odds ratio (DOR) in diagnosis of H. pylori. The DOR of genes which showed the highest performance of stool PCR tests was as follows: 23S rRNA 152.5 (95% CI: 55.5-418.9), 16S rRNA 67.9 (95%CI: 6.4-714.3), and glmM 68.1 (95%CI: 20.1-231.7). The sensitivity and specificity of stool PCR test are relatively in the same spectrum of other diagnostic methods for the detection of H. pylori infection. In descending order of significance, the most diagnostic candidate genes using PCR detection were 23S rRNA, 16S rRNA, and glmM. PCR for 23S rRNA gene which has the highest performance could be applicable to detect H. pylori infection. © 2017 John Wiley & Sons Ltd.

Results of metallographical diagnostic examination of Navy half-watt thermoelectric converters degraded by accelerated tests

International Nuclear Information System (INIS)

Rosell, F.E. Jr.; Rouklove, P.G.

1977-01-01

To verify the 15-year reliability of the Navy half-watt radioisotope thermoelectric generator (RTG), bismuth--telluride thermoelectric converters were submitted to testing at high temperatures which accelerated the degradation and caused failure of the converters. Metallographic diagnostic examination of failed units verified failure mechanisms. Results of diagnostic examinations are presented

Beam-Based Diagnostics of RF-Breakdown in the Two-Beam Test-Stand in CTF3

CERN Document Server

Johnson, M

2007-01-01

The general outline of a beam-based diagnostic method of RF-breakdown, using BPMs, at the two-beam test-stand in CTF3 is discussed. The basic components of the set-up and their functions in the diagnostic are described. Estimations of the expected error in the measured parameters are performed.

Estimating the true accuracy of diagnostic tests for dengue infection using bayesian latent class models.

Directory of Open Access Journals (Sweden)

Wirichada Pan-ngum

Full Text Available Accuracy of rapid diagnostic tests for dengue infection has been repeatedly estimated by comparing those tests with reference assays. We hypothesized that those estimates might be inaccurate if the accuracy of the reference assays is not perfect. Here, we investigated this using statistical modeling.Data from a cohort study of 549 patients suspected of dengue infection presenting at Colombo North Teaching Hospital, Ragama, Sri Lanka, that described the application of our reference assay (a combination of Dengue IgM antibody capture ELISA and IgG antibody capture ELISA and of three rapid diagnostic tests (Panbio NS1 antigen, IgM antibody and IgG antibody rapid immunochromatographic cassette tests were re-evaluated using bayesian latent class models (LCMs. The estimated sensitivity and specificity of the reference assay were 62.0% and 99.6%, respectively. Prevalence of dengue infection (24.3%, and sensitivities and specificities of the Panbio NS1 (45.9% and 97.9%, IgM (54.5% and 95.5% and IgG (62.1% and 84.5% estimated by bayesian LCMs were significantly different from those estimated by assuming that the reference assay was perfect. Sensitivity, specificity, PPV and NPV for a combination of NS1, IgM and IgG cassette tests on admission samples were 87.0%, 82.8%, 62.0% and 95.2%, respectively.Our reference assay is an imperfect gold standard. In our setting, the combination of NS1, IgM and IgG rapid diagnostic tests could be used on admission to rule out dengue infection with a high level of accuracy (NPV 95.2%. Further evaluation of rapid diagnostic tests for dengue infection should include the use of appropriate statistical models.

Comparison of a New and Rapid Method: Brucella Coombs Gel Test With Other Diagnostic Tests.

Science.gov (United States)

Kalem, Fatma; Ergün, Ayşe Gül; Durmaz, Süleyman; Doğan, Metin; Ertuğrul, Ömür; Gündem, Seval

2016-09-01

The aim of this study was to detect reliability of Brucella Coombs gel test (BCGT) by comparing with with ELISA (IgG + IgM), Standard agglutination test, and Brucella immunocapture agglutination methods in serological diagnosis of brucellosis. Brucella Coombs gel test (BCGT), Brucella ELISA (IgG + IgM), Standard agglutination test, and Brucella immunocapture agglutination tests of 78 patients with presumptive diagnosis of brucellosis which were sent to Microbiology Laboratory of Konya Numune Hospital from various regions of Konya were studied. Of 78 patients with ELISA IgG and IgM, STA, BICA and BCGT; 26, 21, 10, 12 and 12 were positive. When compared with BICA, the sensitivity and specifity of BCGT were 100% and 100%, respectively. According to results BCGT can be used as a diagnostic test in routine laboratories after more comprehensive studies in control groups and patients. © 2016 Wiley Periodicals, Inc.

[Diagnostic capacity of skin prick test in egg and cow's milk allergic infants].

Science.gov (United States)

Yan, Jun-mei; Chen, Jing; Li, Hai-qi; Hu, Yan

2011-05-01

Mean diameter is the most common used parameter for wheal response assessment after skin prick test. This study aimed to investigate the diagnostic capacity of mean diameter according to the outcome of oral food challenge, and to determine the cut-off points that could render food challenges unnecessary. Data of 173 children referred to the Division of Primary Child Health Care for the evaluation of suspected food allergy were prospectively studied. All children underwent skin prick test and open food challenge to the relevant food(s) in clinic. The mean wheal diameter of skin prick test was measured, and open food challenge was performed to confirm food allergy. The SPSS software package version 13.0 for windows (SPSS, Chicago, IL, USA) was used for all statistical analysis. Open food challenge was taken as the gold standard for diagnosis. Diagnostic capacity of skin prick test, including the sensitivity, specificity, positive predictive value, negative predictive value, was calculated by cross-table. In addition, receiver operating characteristic curve (ROC) was plotted and area under the curve (AUC) was calculated to quantify the accuracy of the parameter. For the 173 children, 271 open food challenges were performed with egg white, egg yolk and cow's milk, In which 123 were positive, 99 children were diagnosed as food allergy. Cutaneous symptoms (87.0%) were most common, followed by gastrointestinal symptoms (9.8%). The AUC of mean diameter was 0.794 for egg white, 0.804 for egg yolk and 0.904 for cow's milk. The sensitivity of skin prick test with a cut-off value of ≥ 3 mm was ranged from 71% to 87%, while the specificity was between 31% and 57%. The authors also defined food specific skin prick test mean diameters that were 100% diagnostic for allergy to egg white (≥ 8.5 mm), egg yolk (≥ 5.5 mm), cow's milk (≥ 5.5 mm). Predictive decision points for a positive outcome of food challenges can be calculated for egg and cow's milk using mean diameter. It

Diagnostic efficacy of in vitro methods vs. skin testing in patients with inhalant allergies

International Nuclear Information System (INIS)

Corey, J.P.; Liudahl, J.J.; Young, S.A.; Rodman, S.M.

1991-01-01

The purpose of our study was to investigate the diagnostic efficacy of two selected methods of in vitro allergy testing. Specifically, the PRIST/modified RAST I125 isotope systems and the Quantizyme/modified EAST alkaline phosphatase method were compared. The time, expense, convenience, and diagnostic efficacy of the two procedures are discussed. Special attention is given to the practicality of each method for the practicing physician

Single and Combined Diagnostic Value of Clinical Features and Laboratory Tests in Acute Appendicitis

NARCIS (Netherlands)

Laméris, Wytze; van Randen, Adrienne; Go, Peter M. N. Y. H.; Bouma, Wim H.; Donkervoort, Sandra C.; Bossuyt, Patrick M. M.; Stoker, Jaap; Boermeester, Marja A.

2009-01-01

Objectives: The objective was to evaluate the diagnostic accuracy of clinical features and laboratory test results in detecting acute appendicitis. Methods: Clinical features and laboratory test results were prospectively recorded in a consecutive series of 1,101 patients presenting with abdominal

Diagnostic Accuracy of Molecular Amplification Tests for Human African Trypanosomiasis-Systematic Review

NARCIS (Netherlands)

Mugasa, Claire M.; Adams, Emily R.; Boer, Kimberly R.; Dyserinck, Heleen C.; Büscher, Philippe; Schallig, Henk D. H. F.; Leeflang, Mariska M. G.

2012-01-01

Background: A range of molecular amplification techniques have been developed for the diagnosis of Human African Trypanosomiasis (HAT); however, careful evaluation of these tests must precede implementation to ensure their high clinical accuracy. Here, we investigated the diagnostic accuracy of

Urinary tract infections in general practice patients: diagnostic tests versus bacteriological culture.

NARCIS (Netherlands)

Nys, S.; Merode, T. van; Bartelds, A.I.M.; Stobberingh, E.E.

2006-01-01

Objectives: Urinary tract infections (UTIs) are common bacterial infections encountered in general practice. For the optimal treatment the general practitioner (GP) should rely on the results of diagnostic tests and recent antimicrobial susceptibility of uropathogens. Patients and methods: In total

High-pressure liquid chromatographic assay of Bay n 7133 in human serum.

OpenAIRE

Fasching, C E; Hughes, C E; Hector, R F; Peterson, L R

1984-01-01

A high-pressure liquid chromatographic method that includes a Sep-Pak (Waters Associates, Inc., Milford , Mass.) preparation of human serum was employed for the quantitative assay of Bay n 7133. Drug levels of 0.1 to 20 micrograms/ml could be detected. No interference from amphotericin B was found in the chromatographic analysis of Bay n 7133.

Immuno-Oncology-The Translational Runway for Gene Therapy: Gene Therapeutics to Address Multiple Immune Targets.

Science.gov (United States)

Weß, Ludger; Schnieders, Frank

2017-12-01

Cancer therapy is once again experiencing a paradigm shift. This shift is based on extensive clinical experience demonstrating that cancer cannot be successfully fought by addressing only single targets or pathways. Even the combination of several neo-antigens in cancer vaccines is not sufficient for successful, lasting tumor eradication. The focus has therefore shifted to the immune system's role in cancer and the striking abilities of cancer cells to manipulate and/or deactivate the immune system. Researchers and pharma companies have started to target the processes and cells known to support immune surveillance and the elimination of tumor cells. Immune processes, however, require novel concepts beyond the traditional "single-target-single drug" paradigm and need parallel targeting of diverse cells and mechanisms. This review gives a perspective on the role of gene therapy technologies in the evolving immuno-oncology space and identifies gene therapy as a major driver in the development and regulation of effective cancer immunotherapy. Present challenges and breakthroughs ranging from chimeric antigen receptor T-cell therapy, gene-modified oncolytic viruses, combination cancer vaccines, to RNA therapeutics are spotlighted. Gene therapy is recognized as the most prominent technology enabling effective immuno-oncology strategies.

Phage-Mediated Immuno-PCR for Ultrasensitive Detection of Cry1Ac Protein Based on Nanobody.

Science.gov (United States)

Liu, Yuanyuan; Jiang, Dongjian; Lu, Xin; Wang, Wei; Xu, Yang; He, Qinghua

2016-10-11

The widespread use of Cry proteins in transgenic plants for insect control has raised concerns about the environment and food safety in the public. An effective detection method for introduced Cry proteins is of significance for environmental risk assessment and product quality control. This paper describes a novel phage mediated immuno-PCR (iPCR) for the ultrasensitive determination of Cry proteins based on nanobodies. Three nanobodies against Cry1Ac protein were obtained from a naı̈ve phage displayed nanobody library without animal immunization process and were applied to the iPCR assay for Cry1Ac. The phage-mediated iPCR for Cry1Ac based on nanobodies showed a dynamic range of 0.001-100 ng/mL and a limit detection of 0.1 pg/mL. Specific measurement of this established method was performed by testing cross-reativity of other Cry1Ac analogues, and the result showed negligible cross-reactivity with other test Cry proteins (Cry1Ab, Cry1F, Cry3B). Furthermore, the phage-mediated iPCR based on nanobody should be easily applicable to the detection of many other Cry proteins.

Development of an assay for urinary free cortisol determination on the Technicon Immuno 1 system

International Nuclear Information System (INIS)

Letellier, M.; Levesque, A.; Daigle, F.

1997-01-01

To develop and evaluate a method using an ethyl acetate extraction procedure for the determination of urinary free cortisol on the Technicon Immuno 1 system from Bayer Corporation. We tested the assay precision, linearity, and correlation with the Urinary Kallestad Quanticoat Cortisol radioimmunoassay. We also studied the efficiency of the extraction procedure, performed a cross-reactivity study with different cortisol metabolites, and determined the reference values. The assay shows within-run CVs varying from 1.6 to 5.3% and between-day CVs from 2.7 to 6.1% for urinary free cortisol concentrations from 58 to 1097 nmol/L. The assay demonstrates an excellent linearity and a very good correlation with the Kallestad Quanticoat Cortisol assay (slope 0.94, y-intercept = 29 nmol/L, Sy|x = 54 nmol/L, r = 0.996). The reference values were estimated at 42-281 nmol/d. The extraction procedure shows an average recovery of 99.0% and minimal interference with the cortisol metabolites tested with the exception of cortisone. The evaluation shows that the developed assay has the analytical characteristics required for its utilization in a clinical laboratory. (author)

Remote visual testing (RVT) for the diagnostic inspection of feedwater heaters

International Nuclear Information System (INIS)

Nugent, M.J.; Pellegrino, B.A.

1991-01-01

In this paper the benefits and limitations of Non-Destructive Testing (NDT) on feedwater heaters will be briefly reviewed. All Remote Visual Testing (RVT) devices including borescopes, fiberscopes, videoborescopes and Closed Circuit Television (CCTV) cameras will be discussed along with currently accepted formats for documentation. The benefits of a comprehensive in-place inspection involving Remote Visual Testing will be discussed in relationship to its diagnostic capabilities. The results of eight post-service heater inspections will be discussed along with the root cause of failure of seven unique failure mechanisms. These inspections, including FWH access, RVT tool and data analysis, will be detailed

Pyrolysis gas chromatographic atomic emission detection for sediments, coals and other petrochemical precursors

Energy Technology Data Exchange (ETDEWEB)

Seeley, J.A.; Zeng, Y.D.; Uden, P.C.; Eglinton, T.I.; Ericson, I. (Massachusetts University, Amherst, MA (USA). Dept. of Chemistry)

1992-09-01

On-line flash pyrolysis coupled to a capillary gas chromatograph for the characterization of marine sediments, coals and other heterogeneous solid samples is described. A helium microwave-induced plasma is used for chromatographic detection by atomic emission spectrometry. Simultaneous multi-element detection is achieved with a photodiode array detector. The optical path of the gas chromatographic atomic emission detector is purged with helium, allowing simultaneous, sensitive detection of atomic emission from sulfur 181 nm, phosphorous 186 nm, arsenic 189 nm, selenium 196 nm and carbon 193 nm. Several sediment and coal samples have been analysed for their carbon, nitrogen, sulfur, oxygen, phosphorous, arsenic and selenium content. Qualitative information indicating the occurrence and distribution of these elements in the samples can be used to gauge the relative stage of diagenetic evolution of the samples and provide information on their depositional environment. In some instances the chromatographic behaviour of the compounds produced upon pyrolysis is improved through on-line alkylation. This on-line derivatization is achieved by adding liquid reagents to the pyrolysis probe or by adding liquid reagents to the pyrolysis probe or by adding solid reagents either to the solid sample or by packing the reagent in the injection port of the chromatograph.

Chromatographic generator systems for the actinides and natural decay series elements

International Nuclear Information System (INIS)

McAlister, D.R.; Horwitz, E.P.

2011-01-01

This work describes chromatographic radionuclide generator systems for the production of actinides and natural decay series elements. The generator systems begin with alpha emitting parent radioisotopes with half-lives (T 1/2 ) of greater than one year and produce alpha or beta emitting radioisotopes with half-lives of hours to days. Chromatographic systems were chosen to minimize radiolytic damage to chromatographic supports, preserve the parent activity for repeated use, provide high purity daughter radionuclide tracers, and to minimize or eliminate the need for evaporation of solutions of the parent or daughter nuclides. Useful secondary separations involving the daughters of the initial parent radionuclide are also described. Separation systems for 210 Bi, 210 Po, 211 Pb, 212 Pb, 223 Ra, 224 Ra, 225 Ra, 225 Ac, 227 Th, 228 Th, 231 Th, 234 Th, and 239 Np are outlined in detail. (orig.)

Diagnostic validation of three test methods for detection of cyprinid herpesvirus 3 (CyHV-3).

Science.gov (United States)

Clouthier, Sharon C; McClure, Carol; Schroeder, Tamara; Desai, Megan; Hawley, Laura; Khatkar, Sunita; Lindsay, Melissa; Lowe, Geoff; Richard, Jon; Anderson, Eric D

2017-03-06

Cyprinid herpesvirus 3 (CyHV-3) is the aetiological agent of koi herpesvirus disease in koi and common carp. The disease is notifiable to the World Organisation for Animal Health. Three tests-quantitative polymerase chain reaction (qPCR), conventional PCR (cPCR) and virus isolation by cell culture (VI)-were validated to assess their fitness as diagnostic tools for detection of CyHV-3. Test performance metrics of diagnostic accuracy were sensitivity (DSe) and specificity (DSp). Repeatability and reproducibility were measured to assess diagnostic precision. Estimates of test accuracy, in the absence of a gold standard reference test, were generated using latent class models. Test samples originated from wild common carp naturally exposed to CyHV-3 or domesticated koi either virus free or experimentally infected with the virus. Three laboratories in Canada participated in the precision study. Moderate to high repeatability (81 to 99%) and reproducibility (72 to 97%) were observed for the qPCR and cPCR tests. The lack of agreement observed between some of the PCR test pair results was attributed to cross-contamination of samples with CyHV-3 nucleic acid. Accuracy estimates for the PCR tests were 99% for DSe and 93% for DSp. Poor precision was observed for the VI test (4 to 95%). Accuracy estimates for VI/qPCR were 90% for DSe and 88% for DSp. Collectively, the results show that the CyHV-3 qPCR test is a suitable tool for surveillance, presumptive diagnosis and certification of individuals or populations as CyHV-3 free.

Chromatographic background drift correction coupled with parallel factor analysis to resolve coelution problems in three-dimensional chromatographic data: quantification of eleven antibiotics in tap water samples by high-performance liquid chromatography coupled with a diode array detector.

Science.gov (United States)

Yu, Yong-Jie; Wu, Hai-Long; Fu, Hai-Yan; Zhao, Juan; Li, Yuan-Na; Li, Shu-Fang; Kang, Chao; Yu, Ru-Qin

2013-08-09

Chromatographic background drift correction has been an important field of research in chromatographic analysis. In the present work, orthogonal spectral space projection for background drift correction of three-dimensional chromatographic data was described in detail and combined with parallel factor analysis (PARAFAC) to resolve overlapped chromatographic peaks and obtain the second-order advantage. This strategy was verified by simulated chromatographic data and afforded significant improvement in quantitative results. Finally, this strategy was successfully utilized to quantify eleven antibiotics in tap water samples. Compared with the traditional methodology of introducing excessive factors for the PARAFAC model to eliminate the effect of background drift, clear improvement in the quantitative performance of PARAFAC was observed after background drift correction by orthogonal spectral space projection. Copyright © 2013 Elsevier B.V. All rights reserved.

Development and testing of a diagnostic system for intelligen distributed control at EBR-2

International Nuclear Information System (INIS)

Edwards, R.M.; Ruhl, D.W.; Klevans, E.H.; Robinson, G.E.

1990-01-01

A diagnostic system is under development for demonstration of Intelligent Distributed Control at the Experimental Breeder Reactor (EBR--II). In the first phase of the project a diagnostic system is being developed for the EBR-II steam plant based on the DISYS expert systems approach. Current testing uses recorded plant data and data from simulated plant faults. The dynamical simulation of the EBR-II steam plant uses the Babcock and Wilcox (B ampersand W) Modular Modeling System (MMS). At EBR-II the diagnostic system operates in the UNIX workstation and receives live plant data from the plant Data Acquisition System (DAS). Future work will seek implementation of the steam plant diagnostic in a distributed manner using UNIX based computers and Bailey microprocessor-based control system. 10 refs., 6 figs

9 CFR 130.17 - User fees for other veterinary diagnostic laboratory tests performed at NVSL (excluding FADDL) or...

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false User fees for other veterinary... FEES USER FEES § 130.17 User fees for other veterinary diagnostic laboratory tests performed at NVSL (excluding FADDL) or at authorized sites. (a) User fees for veterinary diagnostics tests performed at the...

9 CFR 130.16 - User fees for veterinary diagnostic serology tests performed at NVSL (excluding FADDL) or at...

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false User fees for veterinary diagnostic serology tests performed at NVSL (excluding FADDL) or at authorized sites. 130.16 Section 130.16 Animals... USER FEES § 130.16 User fees for veterinary diagnostic serology tests performed at NVSL (excluding...

Chromatographic separation of low-temperature tar. Part II

Energy Technology Data Exchange (ETDEWEB)

Terres, E; Gebert, F; Huelsemann, H; Petereit, H; Toepsch, H; Ruppert, W

1955-01-01

Chromatographic methods and apparatus are discussed. The Folin-Denis reagent (Na tungstate molybdate in H/sub 3/PO/sub 4/) is used for developing paper chromatograms of phenol mixtures. Other reagents are given.

A Review of Neuropathic Pain: From Diagnostic Tests to Mechanisms

OpenAIRE

Truini, Andrea

2017-01-01

Neuropathic pain develops when the somatosensory nervous system is affected by a lesion or disease. Diagnostic tests aimed at assessing somatosensory afferent pathway damage are therefore useful for diagnosing neuropathic pain. Neuropathic pain manifests with a range of different symptoms such as ongoing burning pain, squeezing or pressure pain, paroxysmal electric shock-like sensations, stabbing pain, or mechanical dynamic allodynia. The various types of neuropathic pain are associated with ...

Diagnostic Accuracy of Quantitative Sensory Testing to Discriminate Inflammatory Toothache and Intraoral Neuropathic Pain.

Science.gov (United States)

Porporatti, André Luís; Costa, Yuri Martins; Stuginski-Barbosa, Juliana; Bonjardim, Leonardo Rigoldi; Duarte, Marco Antônio Hungaro; Conti, Paulo César Rodrigues

2015-10-01

A differential diagnosis between inflammatory toothache (IT) and intraoral neuropathic pain is challenging. The aim of this diagnostic study was to quantify somatosensory function of subjects with IT (acute pulpitis) and atypical odontalgia (AO, intraoral neuropathic pain) and healthy volunteers and to quantify how accurately quantitative sensory testing (QST) discriminates an IT or AO diagnosis. The sample consisted of 60 subjects equally divided (n = 20) into 3 groups: (1) IT, (2) AO, and (3) control. A sequence of 4 QST methods was performed over the dentoalveolar mucosa in the apical maxillar or mandibular area: mechanical detection threshold, pain detection threshold (PDT), dynamic mechanical allodynia, and temporal summation. One-way analysis of variance, Tukey post hoc analyses, and z score transformation were applied to the data. In addition, the receiver operating characteristic curve analysis, diagnostic accuracy, sensitivity, specificity, likelihood ratios, and diagnostic odds ratio of the QST methods were calculated (α = 5%). Somatosensory abnormalities were found for the AO group, which is consistent with a low detection threshold to touch and pain and the presence of mechanical allodynia. For the IT group, no somatosensory abnormality was observed when compared with the control group. The most accurate QST to discriminate the diagnostic differences between IT and healthy individuals is the PDT. The diagnostic differences between AO and healthy individuals and between IT and AO are best discriminated with the mechanical detection threshold, PDT, and dynamic mechanical allodynia. The proposed QST methods may aid in the differential diagnosis between IT and AO with strong accuracy and may be used as complementary diagnostic tests. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Chromatographic determination of silicon and phosphorus as molybdic heteropoly acids with preconcentration

International Nuclear Information System (INIS)

Tikhomirova, T.I.; Krokhin, O.V.; Dubovik, D.B.; Ivanov, A.V.; Shpigun, O.A.

2002-01-01

Chromatographic behaviour of silicon and phosphorus as molybdic heteropoly acids with preconcentration as ion associations of heteropoly acid with tributylammonium bromide was studied. The technique of simultaneous analysis of silicon and phosphorus was developed. During investigation into the effect of acetonitril content in the probe on the form of chromatographic peak of molybdosilicic acid the negative influence of acetonitril on the form of peak was ascertained. This effect may be eliminated by the lowering of acetonitril content up to 50 %. It was found that under these conditions the chromatographic peak practically was absent, because of the heteropoly acid of the Mo(VI) abundance transformed in the MoO 2 2+ cation form without reaction with tributylammonium cation during concentration of heteropoly acid [ru

A diagnostic model incorporating P50 sensory gating and neuropsychological tests for schizophrenia.

Directory of Open Access Journals (Sweden)

Jia-Chi Shan

Full Text Available OBJECTIVES: Endophenotypes in schizophrenia research is a contemporary approach to studying this heterogeneous mental illness, and several candidate neurophysiological markers (e.g. P50 sensory gating and neuropsychological tests (e.g. Continuous Performance Test (CPT and Wisconsin Card Sorting Test (WCST have been proposed. However, the clinical utility of a single marker appears to be limited. In the present study, we aimed to construct a diagnostic model incorporating P50 sensory gating with other neuropsychological tests in order to improve the clinical utility. METHODS: We recruited clinically stable outpatients meeting DSM-IV criteria of schizophrenia and age- and gender-matched healthy controls. Participants underwent P50 sensory gating experimental sessions and batteries of neuropsychological tests, including CPT, WCST and Wechsler Adult Intelligence Scale Third Edition (WAIS-III. RESULTS: A total of 106 schizophrenia patients and 74 healthy controls were enrolled. Compared with healthy controls, the patient group had significantly a larger S2 amplitude, and thus poorer P50 gating ratio (gating ratio = S2/S1. In addition, schizophrenia patients had a poorer performance on neuropsychological tests. We then developed a diagnostic model by using multivariable logistic regression analysis to differentiate patients from healthy controls. The final model included the following covariates: abnormal P50 gating (defined as P50 gating ratio >0.4, three subscales derived from the WAIS-III (Arithmetic, Block Design, and Performance IQ, sensitivity index from CPT and smoking status. This model had an adequate accuracy (concordant percentage = 90.4%; c-statistic = 0.904; Hosmer-Lemeshow Goodness-of-Fit Test, p = 0.64>0.05. CONCLUSION: To the best of our knowledge, this is the largest study to date using P50 sensory gating in subjects of Chinese ethnicity and the first to use P50 sensory gating along with other neuropsychological tests

Diagnostic test accuracy of nutritional tools used to identify undernutrition in patients with colorectal cancer: a systematic review.

Science.gov (United States)

Håkonsen, Sasja Jul; Pedersen, Preben Ulrich; Bath-Hextall, Fiona; Kirkpatrick, Pamela

2015-05-15

Effective nutritional screening, nutritional care planning and nutritional support are essential in all settings, and there is no doubt that a health service seeking to increase safety and clinical effectiveness must take nutritional care seriously. Screening and early detection of malnutrition is crucial in identifying patients at nutritional risk. There is a high prevalence of malnutrition in hospitalized patients undergoing treatment for colorectal cancer. To synthesize the best available evidence regarding the diagnostic test accuracy of nutritional tools (sensitivity and specificity) used to identify malnutrition (specifically undernutrition) in patients with colorectal cancer (such as the Malnutrition Screening Tool and Nutritional Risk Index) compared to reference tests (such as the Subjective Global Assessment or Patient Generated Subjective Global Assessment). Patients with colorectal cancer requiring either (or all) surgery, chemotherapy and/or radiotherapy in secondary care. Focus of the review: The diagnostic test accuracy of validated assessment tools/instruments (such as the Malnutrition Screening Tool and Nutritional Risk Index) in the diagnosis of malnutrition (specifically under-nutrition) in patients with colorectal cancer, relative to reference tests (Subjective Global Assessment or Patient Generated Subjective Global Assessment). Types of studies: Diagnostic test accuracy studies regardless of study design. Studies published in English, German, Danish, Swedish and Norwegian were considered for inclusion in this review. Databases were searched from their inception to April 2014. Methodological quality was determined using the Quality Assessment of Diagnostic Accuracy Studies checklist. Data was collected using the data extraction form: the Standards for Reporting Studies of Diagnostic Accuracy checklist for the reporting of studies of diagnostic accuracy. The accuracy of diagnostic tests is presented in terms of sensitivity, specificity, positive

Chemometric approach for development, optimization, and validation of different chromatographic methods for separation of opium alkaloids.

Science.gov (United States)

Acevska, J; Stefkov, G; Petkovska, R; Kulevanova, S; Dimitrovska, A

2012-05-01

The excessive and continuously growing interest in the simultaneous determination of poppy alkaloids imposes the development and optimization of convenient high-throughput methods for the assessment of the qualitative and quantitative profile of alkaloids in poppy straw. Systematic optimization of two chromatographic methods (gas chromatography (GC)/flame ionization detector (FID)/mass spectrometry (MS) and reversed-phase (RP)-high-performance liquid chromatography (HPLC)/diode array detector (DAD)) for the separation of alkaloids from Papaver somniferum L. (Papaveraceae) was carried out. The effects of various conditions on the predefined chromatographic descriptors were investigated using chemometrics. A full factorial linear design of experiments for determining the relationship between chromatographic conditions and the retention behavior of the analytes was used. Central composite circumscribed design was utilized for the final method optimization. By conducting the optimization of the methods in very rational manner, a great deal of excessive and unproductive laboratory research work was avoided. The developed chromatographic methods were validated and compared in line with the resolving power, sensitivity, accuracy, speed, cost, ecological aspects, and compatibility with the poppy straw extraction procedure. The separation of the opium alkaloids using the GC/FID/MS method was achieved within 10 min, avoiding any derivatization step. This method has a stronger resolving power, shorter analysis time, better cost/effectiveness factor than the RP-HPLC/DAD method and is in line with the "green trend" of the analysis. The RP-HPLC/DAD method on the other hand displayed better sensitivity for all tested alkaloids. The proposed methods provide both fast screening and an accurate content assessment of the six alkaloids in the poppy samples obtained from the selection program of Papaver strains.

Giardia duodenalis in Captive Tigers (Panthera tigris, Palawan Bearcats (Arctictis binturong whitei and Asian Palm Civet (Paradoxurus hermaphroditus at a Wildlife Facility in Manila, Philippines

Directory of Open Access Journals (Sweden)

Nick Angelo P. VELANTE

2017-09-01

Full Text Available Background: This study was conducted to determine the prevalence of Giardia duodenalis in captive animals in a wildlife facility. This is the first study conducted in these animals from the facility.Methods: Eight captive tigers (Panthera tigris, two Palawan bearcats (Arctictis binturong whitei and one Asian Palm Civet (Paradoxurus hermaphroditus currently housed at a wildlife facility in Manila, Philippines were considered in 2012. These animals were apparently healthy with no signs of disease during the study. Sample collection was done twice at two months interval where freshly voided fecal samples were grossly examined, characterized and preserved in Sodium Acetate Formalin (SAF. The samples were used to determine the presence of G. duodenalis using modified flotation-sedimentation and commercially available immuno-chromatographic assay test kit.Results: All fecal samples tested were negative for the presence of G. duodenalis trophozoites, and cysts using the former. Furthermore, none of the samples tested positive for and G. duodenalis antigen using immune-chromatographic assay.Conclusion: There is no existing infection of G. duodenalis among captive tigers, Palawan Bearcats and Asian palm civet housed at the wildlife facility. 

The meaning of diagnostic test results: A spreadsheet for swift data analysis

International Nuclear Information System (INIS)

MacEneaney, Peter M.; Malone, Dermot E.

2000-01-01

AIMS: To design a spreadsheet program to: (a) analyse rapidly diagnostic test result data produced in local research or reported in the literature; (b) correct reported predictive values for disease prevalence in any population; (c) estimate the post-test probability of disease in individual patients. MATERIALS AND METHODS: Microsoft Excel TM was used. Section A: a contingency (2 x 2) table was incorporated into the spreadsheet. Formulae for standard calculations [sample size, disease prevalence, sensitivity and specificity with 95% confidence intervals, predictive values and likelihood ratios (LRs)] were linked to this table. The results change automatically when the data in the true or false negative and positive cells are changed. Section B: this estimates predictive values in any population, compensating for altered disease prevalence. Sections C-F: Bayes' theorem was incorporated to generate individual post-test probabilities. The spreadsheet generates 95% confidence intervals, LRs and a table and graph of conditional probabilities once the sensitivity and specificity of the test are entered. The latter shows the expected post-test probability of disease for any pre-test probability when a test of known sensitivity and specificity is positive or negative. RESULTS: This spreadsheet can be used on desktop and palmtop computers. The MS Excel TM version can be downloaded via the Internet from the URL ftp://radiography.com/pub/Rad-data99.xls CONCLUSION: A spreadsheet is useful for contingency table data analysis and assessment of the clinical meaning of diagnostic test results. MacEneaney, P.M., Malone, D.E. (2000)

The behaviour of radionuclides in gas adsorption chromatographic processes with superimposed chemical reactions (chlorides)

International Nuclear Information System (INIS)

Eichler, B.

1996-01-01

Thermochemical relationships are derived describing the gas adsorption chromatographic transport of carrier-free radionuclides. Especially, complex adsorption processes such as dissociative, associative and substitutive adsorption are dealt with. The comparison of experimental with calculated data allows the determination of the type of adsorption reaction, which is the basis of the respective gas chromatographic process. The behaviour of carrier-free radionuclides of elements Pu, Ce, Ru, Co and Cr in thermochromatographic experiments with chlorinating carrier gases can be described as dissociative adsorption of chlorides in higher oxidation states. The gas adsorption chromatographic transport of Zr with oxygen and chlorine containing carrier gas is shown to be a substitutive adsorption process. The consequences of superimposed chemical reactions on the interpretation of results and the conception of gas adsorption chromatographic experiments with carrier-free radionuclides in isothermal columns and in temperature gradient tubes is discussed. (orig.)

Chromatographic characterisation, in vitro antioxidant and free ...

African Journals Online (AJOL)

Chromatographic fractionation and spectroscopic analysis of the ME4 fraction revealed the presence of four compounds namely garcinia biflavonoids GB1 and GB2, garcinal and garcinoic acid. These findings show that these four compounds are partly responsible for the great antioxidant potential of G. kola seeds.

Reactor protection system with automatic self-testing and diagnostic

International Nuclear Information System (INIS)

Gaubatz, D.C.

1996-01-01

A reactor protection system is disclosed having four divisions, with quad redundant sensors for each scram parameter providing input to four independent microprocessor-based electronic chassis. Each electronic chassis acquires the scram parameter data from its own sensor, digitizes the information, and then transmits the sensor reading to the other three electronic chassis via optical fibers. To increase system availability and reduce false scrams, the reactor protection system employs two levels of voting on a need for reactor scram. The electronic chassis perform software divisional data processing, vote 2/3 with spare based upon information from all four sensors, and send the divisional scram signals to the hardware logic panel, which performs a 2/4 division vote on whether or not to initiate a reactor scram. Each chassis makes a divisional scram decision based on data from all sensors. Automatic detection and discrimination against failed sensors allows the reactor protection system to automatically enter a known state when sensor failures occur. Cross communication of sensor readings allows comparison of four theoretically ''identical'' values. This permits identification of sensor errors such as drift or malfunction. A diagnostic request for service is issued for errant sensor data. Automated self test and diagnostic monitoring, sensor input through output relay logic, virtually eliminate the need for manual surveillance testing. This provides an ability for each division to cross-check all divisions and to sense failures of the hardware logic. 16 figs

Gas-chromatographic separation of hydrogen isotopic mixtures

International Nuclear Information System (INIS)

Preda, Anisoara; Bidica, Nicolae

2005-01-01

Full text: Gas chromatographic separation of hydrogen isotopes have been reported in the literature since late of 1950's. Gas chromatography is primarily an analytical method, but because of its properties it may be used in many other fields with excellent results. A simple method is proposed for the gas-chromatographic analysis of complex gas mixtures containing hydrogen isotopes; the method is based on the substantial difference in the thermal conductivity of these isotopes. One of the main disadvantages of the conventional gas chromatography is the long retention times required for the analysis of hydrogen gas mixtures while the column is operated at very low temperature. The method described in this paper was based on using a capillary molecular sieve 5A column operated for this kind of separation at 173 K. The carrier gas was Ne and the detector was TCD. In the paper chromatograms for various carrier flow rates and various hydrogen isotope mixtures are presented. (authors)

[A peak recognition algorithm designed for chromatographic peaks of transformer oil].

Science.gov (United States)

Ou, Linjun; Cao, Jian

2014-09-01

In the field of the chromatographic peak identification of the transformer oil, the traditional first-order derivative requires slope threshold to achieve peak identification. In terms of its shortcomings of low automation and easy distortion, the first-order derivative method was improved by applying the moving average iterative method and the normalized analysis techniques to identify the peaks. Accurate identification of the chromatographic peaks was realized through using multiple iterations of the moving average of signal curves and square wave curves to determine the optimal value of the normalized peak identification parameters, combined with the absolute peak retention times and peak window. The experimental results show that this algorithm can accurately identify the peaks and is not sensitive to the noise, the chromatographic peak width or the peak shape changes. It has strong adaptability to meet the on-site requirements of online monitoring devices of dissolved gases in transformer oil.

Safety and Yield of Diagnostic ERCP in Liver Transplant Patients with Abnormal Liver Function Tests

Directory of Open Access Journals (Sweden)

Jayapal Ramesh

2014-01-01

Full Text Available Background. Abnormal liver enzymes postorthotopic liver transplant (OLT may indicate significant biliary pathology or organ rejection. There is very little known in the literature regarding the current role of diagnostic ERCP in this scenario. Aim. To review the utility of diagnostic ERCP in patients presenting with abnormal liver function tests in the setting of OLT. Methods. A retrospective review of diagnostic ERCPs in patients with OLT from 2002 to 2013 from a prospectively maintained, IRB approved database. Results. Of the 474 ERCPs performed in OLT patients, 210 (44.3%; 95% CI 39.8–48.8 were performed for abnormal liver function tests during the study period. Majority of patients were Caucasian (83.8%, male (62.4% with median age of 55 years (IQR 48–62 years. Biliary cannulation was successful in 99.6% of cases and findings included stricture in 45 (21.4 %; biliary stones/sludge in 23 (11%; biliary dilation alone in 31 (14.8%; and normal in 91 (43.3%. Three (1.4% patients developed mild, self-limiting pancreatitis; one patient (0.5% developed cholangitis and two (1% had postsphincterotomy bleeding. Multivariate analyses showed significant association between dilated ducts on imaging with a therapeutic outcome. Conclusion. Diagnostic ERCP in OLT patients presenting with liver function test abnormalities is safe and frequently therapeutic.

Bias in logistic regression due to imperfect diagnostic test results and practical correction approaches.

Science.gov (United States)

Valle, Denis; Lima, Joanna M Tucker; Millar, Justin; Amratia, Punam; Haque, Ubydul

2015-11-04

Logistic regression is a statistical model widely used in cross-sectional and cohort studies to identify and quantify the effects of potential disease risk factors. However, the impact of imperfect tests on adjusted odds ratios (and thus on the identification of risk factors) is under-appreciated. The purpose of this article is to draw attention to the problem associated with modelling imperfect diagnostic tests, and propose simple Bayesian models to adequately address this issue. A systematic literature review was conducted to determine the proportion of malaria studies that appropriately accounted for false-negatives/false-positives in a logistic regression setting. Inference from the standard logistic regression was also compared with that from three proposed Bayesian models using simulations and malaria data from the western Brazilian Amazon. A systematic literature review suggests that malaria epidemiologists are largely unaware of the problem of using logistic regression to model imperfect diagnostic test results. Simulation results reveal that statistical inference can be substantially improved when using the proposed Bayesian models versus the standard logistic regression. Finally, analysis of original malaria data with one of the proposed Bayesian models reveals that microscopy sensitivity is strongly influenced by how long people have lived in the study region, and an important risk factor (i.e., participation in forest extractivism) is identified that would have been missed by standard logistic regression. Given the numerous diagnostic methods employed by malaria researchers and the ubiquitous use of logistic regression to model the results of these diagnostic tests, this paper provides critical guidelines to improve data analysis practice in the presence of misclassification error. Easy-to-use code that can be readily adapted to WinBUGS is provided, enabling straightforward implementation of the proposed Bayesian models.

The Value of Naproxen Test as a Diagnostic Method to Differentiate Cause of Fever

Directory of Open Access Journals (Sweden)

Omer Coskun

2012-12-01

Full Text Available Objective: Fever of whatever etiology still remains a perplexing problem to both clinicians and investigators. Increasingly, its role in connective tissue diseases, malignancies and other inflammatory disorders is slowly supplanting the exclusivity of the symptom to just infectious conditions. This study aims to determine the sensitivity of the naproxen test and the diagnostic value in patients with a prolonged febrile illness. Methods: We evaluated twenty patients had been administered the naproxen test. Fever lysis after or within the time frame of drug administration was interpreted as a infectious or an infectious condition. Results: Infectious diseases etiology was detected at 15 patients. 12 and 3 of them responded to naproxen test at the first and second days respectively. Two of non-infectious etiology patients remained unanswered. Conclusion: This study clearly showed that the naproxen test cannot be relied upon to guide diagnostic decision making in patients with fever unknown origin. [TAF Prev Med Bull 2012; 11(6.000: 779-782

Secretory immunoglobulin purification from whey by chromatographic techniques.

Science.gov (United States)

Matlschweiger, Alexander; Engelmaier, Hannah; Himmler, Gottfried; Hahn, Rainer

2017-08-15

Secretory immunoglobulins (SIg) are a major fraction of the mucosal immune system and represent potential drug candidates. So far, platform technologies for their purification do not exist. SIg from animal whey was used as a model to develop a simple, efficient and potentially generic chromatographic purification process. Several chromatographic stationary phases were tested. A combination of two anion-exchange steps resulted in the highest purity. The key step was the use of a small-porous anion exchanger operated in flow-through mode. Diffusion of SIg into the resin particles was significantly hindered, while the main impurities, IgG and serum albumin, were bound. In this step, initial purity was increased from 66% to 89% with a step yield of 88%. In a second anion-exchange step using giga-porous material, SIg was captured and purified by step or linear gradient elution to obtain fractions with purities >95%. For the step gradient elution step yield of highly pure SIg was 54%. Elution of SIgA and SIgM with a linear gradient resulted in a step yield of 56% and 35%, respectively. Overall yields for both anion exchange steps were 43% for the combination of flow-through and step elution mode. Combination of flow-through and linear gradient elution mode resulted in a yield of 44% for SIgA and 39% for SIgM. The proposed process allows the purification of biologically active SIg from animal whey in preparative scale. For future applications, the process can easily be adopted for purification of recombinant secretory immunoglobulin species. Copyright © 2017 Elsevier B.V. All rights reserved.

Diagnostic evaluation of rapid tests for scrub typhus in the Indian population is needed.

Science.gov (United States)

Shivalli, Siddharudha

2016-05-12

Owing to frequent outbreaks witnessed in different parts of the country in the recent past, scrub typhus is being described as a re-emerging infectious disease in India. Differentiating scrub typhus from other endemic diseases like malaria, leptospirosis, dengue fever, typhoid, etc. is difficult due to overlapping clinical features and a lower positivity for eschars in Asian populations. Hence, the diagnosis heavily relies on laboratory tests. Costs and the need of technical expertise limit the wide use of indirect immunoperoxidase or immunofluorescence assays, ELISA and PCR. The Weil-Felix test is the most commonly used and least expensive serological test, but lacks both sensitivity and specificity. Hence, the diagnosis of scrub typhus is often delayed or overlooked. With due consideration of the cost, rapidity, single test result and simplicity of interpretation, rapid diagnostic tests have come into vogue. However, evaluation of rapid diagnostic tests for scrub typhus in the Indian population is needed to justify or discourage their use. Research studies are needed to find the most suitable test in terms of the rapidity of the result, simplicity of the procedure, ease of interpretation and cost to be used in the Indian populace.

9 CFR 130.15 - User fees for veterinary diagnostic isolation and identification tests performed at NVSL...

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false User fees for veterinary diagnostic isolation and identification tests performed at NVSL (excluding FADDL) or other authorized site. 130.15... AGRICULTURE USER FEES USER FEES § 130.15 User fees for veterinary diagnostic isolation and identification...

Utilisation du test GeneXpert pour le diagnostic de la tuberculose au ...

African Journals Online (AJOL)

Utilisation du test GeneXpert pour le diagnostic de la tuberculose au service des maladies infectieuses du CHNU de Fann. Sylvie Audrey Diop, Aminata Massaly, Daye Ka, Noel Magloire Manga, Louise Fortes-Déguénonvo, Cheikh Tidiane Ndour, Viviane Marie Pierre Cisse, Moussa Seydi ...

Mathematics Diagnostic Testing in Engineering: An International Comparison between Ireland and Portugal

Science.gov (United States)

Carr, M.; Fidalgo, C.; Bigotte de Almeida, M. E.; Branco, J. R.; Santos, V.; Murphy, E.; Ní Fhloinn, E.

2015-01-01

Concern has been expressed throughout Europe about the significant deficiencies in the basic mathematical skills of many engineering undergraduates. Mathematics diagnostic tests in the UK, Ireland and Portugal have shown these shortcomings, which provide a challenge to those striving to introduce more innovative educational practices into…

Sterilization of freeze dried manila clam (Ruditapea philippinarum) porridge for immuno-compromised patients

Energy Technology Data Exchange (ETDEWEB)

Song, Beom Seok; Park, Jae Nam [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

2017-02-15

This study was conducted to evaluate the combined effect of gamma irradiation and different conditions (vacuum packaging, antioxidant and freezing) on the microbiological and sensory characteristics of freeze dried Manila clam porridge (MCP) for immuno-compromised patient food. McP can be sterilized at 1 kGy to 10 kGy. the initial counts of total aerobic bacteria and yeast molds in the non-irradiated MCP were 2.4±0.5 and 1.2±0.3 log CFU g{sup -}'1, respectively, but gamma irradiation significantly decreased the total aerobic bacteria to below the detection limit (1 log CFU g{sup -1}) (5 kGy). Moreover, gamma irradiation effectively eliminated yeasts/molds at dose below than 1 kGy. However, gamma irradiation accelerated the increase of lipid oxidation and therefore, decreased the sensory characteristics of MCP as irradiation dose increased. to improve the sensory qualities of gamma irradiated MCP, combination treatment (vacuum packaging, 0.1% vitamin c) were applied. there was no significant difference in the overall acceptance scores between the combined-treatment sample (5.6 points) and the non-irradiated samples (6.0). the results indicate that combination treatment (vacuum packaging, 0.1% vitamin c) may help to maintain the quality of MCP. therefore, it considered that irradiation of MCP with combined treatment and this is an effective method for the consumption as a special purpose food such as for space travel or immuno-compromised patients.

Sterilization of freeze dried manila clam (Ruditapea philippinarum) porridge for immuno-compromised patients

International Nuclear Information System (INIS)

Song, Beom Seok; Park, Jae Nam

2017-01-01

This study was conducted to evaluate the combined effect of gamma irradiation and different conditions (vacuum packaging, antioxidant and freezing) on the microbiological and sensory characteristics of freeze dried Manila clam porridge (MCP) for immuno-compromised patient food. McP can be sterilized at 1 kGy to 10 kGy. the initial counts of total aerobic bacteria and yeast molds in the non-irradiated MCP were 2.4±0.5 and 1.2±0.3 log CFU g"-'1, respectively, but gamma irradiation significantly decreased the total aerobic bacteria to below the detection limit (1 log CFU g"-"1) (5 kGy). Moreover, gamma irradiation effectively eliminated yeasts/molds at dose below than 1 kGy. However, gamma irradiation accelerated the increase of lipid oxidation and therefore, decreased the sensory characteristics of MCP as irradiation dose increased. to improve the sensory qualities of gamma irradiated MCP, combination treatment (vacuum packaging, 0.1% vitamin c) were applied. there was no significant difference in the overall acceptance scores between the combined-treatment sample (5.6 points) and the non-irradiated samples (6.0). the results indicate that combination treatment (vacuum packaging, 0.1% vitamin c) may help to maintain the quality of MCP. therefore, it considered that irradiation of MCP with combined treatment and this is an effective method for the consumption as a special purpose food such as for space travel or immuno-compromised patients

Validated high performance liquid chromatographic (HPLC) method ...

African Journals Online (AJOL)

STORAGESEVER

2010-02-22

Feb 22, 2010 ... specific and accurate high performance liquid chromatographic method for determination of ZER in micro-volumes ... tional medicine as a cure for swelling, sores, loss of appetite and ... Receptor Activator for Nuclear Factor κ B Ligand .... The effect of ... be suitable for preclinical pharmacokinetic studies. The.

A Comparison of Salivary Steroid Levels during Diagnostic Tests for Adrenal Insufficiency

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Michaela Dušková

2016-01-01

Full Text Available Numerous diagnostic tests are used to evaluate the hypothalamic-pituitary-adrenal axis (HPA axis. The gold standard is still considered the insulin tolerance test (ITT, but this test has many limitations. Current guidelines therefore recommend the Synacthen test first when an HPA axis insufficiency is suspected. However, the dose of Synacthen that is diagnostically most accurate and sensitive is still a matter of debate. We investigated 15 healthy men with mean/median age 27.4/26 (SD ±4.8 years, and mean/median BMI (body mass index 25.38/24.82 (SD ±3.2 kg/m2. All subjects underwent 4 dynamic tests of the HPA axis, specifically 1 μg, 10 μg, and 250 μg Synacthen (ACTH tests and an ITT. Salivary cortisol, cortisone, pregnenolone, and DHEA (dehydroepiandrosterone were analysed using liquid chromatography-tandem mass spectrometry. During the ITT maximum salivary cortisol levels over 12.5 nmol/l were found at 60 minutes. Maximum cortisol levels in all of the Synacthen tests were higher than this; however, demonstrating that sufficient stimulation of the adrenal glands was achieved. Cortisone reacted similarly as cortisol, i.e. we did not find any change in the ratio of cortisol to cortisone. Pregnenolone and DHEA were higher during the ITT, and their peaks preceded the cortisol peak. There was no increase of pregnenolone or DHEA in any of the Synacthen tests. We demonstrate that the 10 μg Synacthen dose is sufficient stimulus for testing the HPA axis and is also a safe and cost-effective alternative. This dose also largely eliminates both false negative and false positive results.

Performance and Pain Tolerability of Current Diagnostic Allergy Skin Prick Test Devices.

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Tversky, Jody R; Chelladurai, Yohalakshmi; McGready, John; Hamilton, Robert G

2015-01-01

Allergen skin prick testing remains an essential tool for diagnosing atopic disease and guiding treatment. Sensitivity needs to be defined for newly introduced devices. Our aim was to compare the performance of 10 current allergy skin prick test devices. Single- and multiheaded skin test devices (n = 10) were applied by a single operator in a prospective randomized manner. Histamine (1 and 6 mg/mL) and control diluent were introduced at 6 randomized locations onto the upper and lower arms of healthy subjects. Wheal and flare reactions were measured independently by 2 masked technicians. Twenty-four subjects provided consent, and 768 skin tests were placed. Mean wheal diameter among devices differed from 3.0 mm (ComforTen; Hollister-Stier, Spokane, Wash) to 6.8 mm (UniTest PC; Lincoln Diagnostics, Decatur, Ill) using 1 mg/mL histamine (P Diagnostics, Decatur, Ill; and Sharp-Test; Panatrex, Placentia, Calif) using 6 mg/mL histamine (P pain score of less than 4 on a 10-point visual analog scale. Pain scores were higher among women, but this did not reach statistical significance. The Multi-Test PC and the UniTest PC had the lowest pain scores compared with the other devices. All 10 skin prick test devices displayed good analytical sensitivity and specificity; however, 3 mm cannot arbitrarily be used as a positive threshold. The use of histamine at 1 mg/mL is unacceptable for certain devices but may be preferable for the most sensitive devices. On average, there was no pain score difference between multiheaded and single-head devices. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

The Hug-up Test: A New, Sensitive Diagnostic Test for Supraspinatus Tears

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Yu-Lei Liu

2016-01-01

Full Text Available Background: The supraspinatus tendon is the most commonly affected tendon in rotator cuff tears. Early detection of a supraspinatus tear using an accurate physical examination is, therefore, important. However, the currently used physical tests for detecting supraspinatus tears are poor diagnostic indicators and involve a wide range of sensitivity and specificity values. Therefore, the aim of this study was to establish a new physical test for the diagnosis of supraspinatus tears and evaluate its accuracy in comparison with conventional tests. Methods: Between November 2012 and January 2014, 200 consecutive patients undergoing shoulder arthroscopy were prospectively evaluated preoperatively. The hug-up test, empty can (EC test, full can (FC test, Neer impingement sign, and Hawkins-Kennedy impingement sign were used and compared statistically for their accuracy in terms of supraspinatus tears, with arthroscopic findings as the gold standard. Muscle strength was precisely quantified using an electronic digital tensiometer. Results: The prevalence of supraspinatus tears was 76.5%. The hug-up test demonstrated the highest sensitivity (94.1%, with a low negative likelihood ratio (NLR, 0.08 and comparable specificity (76.6% compared with the other four tests. The area under the receiver operating characteristic curve for the hug-up test was 0.854, with no statistical difference compared with the EC test (z = 1.438, P = 0.075 or the FC test (z = 1.498, P = 0.067. The hug-up test showed no statistical difference in terms of detecting different tear patterns according to the position (χ2 = 0.578, P = 0.898 and size (Fisher′s exact test, P > 0.999 compared with the arthroscopic examination. The interobserver reproducibility of the hug-up test was high, with a kappa coefficient of 0.823. Conclusions: The hug-up test can accurately detect supraspinatus tears with a high sensitivity, comparable specificity, and low NLR compared with the conventional

Rapid antigen detection test for respiratory syncytial virus diagnosis as a diagnostic tool

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Flávio da Silva Mesquita

2017-05-01

Conclusions: This study demonstrated that the QuickVue® RSV Test Kit can be effective in early detection of Respiratory syncytial virus in nasopharyngeal aspirate and is reliable for use as a diagnostic tool in pediatrics.

Diagnostic validity of physical examination tests for common knee disorders: An overview of systematic reviews and meta-analysis.

Science.gov (United States)

Décary, Simon; Ouellet, Philippe; Vendittoli, Pascal-André; Roy, Jean-Sébastien; Desmeules, François

2017-01-01

More evidence on diagnostic validity of physical examination tests for knee disorders is needed to lower frequently used and costly imaging tests. To conduct a systematic review of systematic reviews (SR) and meta-analyses (MA) evaluating the diagnostic validity of physical examination tests for knee disorders. A structured literature search was conducted in five databases until January 2016. Methodological quality was assessed using the AMSTAR. Seventeen reviews were included with mean AMSTAR score of 5.5 ± 2.3. Based on six SR, only the Lachman test for ACL injuries is diagnostically valid when individually performed (Likelihood ratio (LR+):10.2, LR-:0.2). Based on two SR, the Ottawa Knee Rule is a valid screening tool for knee fractures (LR-:0.05). Based on one SR, the EULAR criteria had a post-test probability of 99% for the diagnosis of knee osteoarthritis. Based on two SR, a complete physical examination performed by a trained health provider was found to be diagnostically valid for ACL, PCL and meniscal injuries as well as for cartilage lesions. When individually performed, common physical tests are rarely able to rule in or rule out a specific knee disorder, except the Lachman for ACL injuries. There is low-quality evidence concerning the validity of combining history elements and physical tests. Copyright © 2016 Elsevier Ltd. All rights reserved.

Self Diagnostic Accelerometer Testing on the C-17 Aircraft

Science.gov (United States)

Tokars, Roger P.; Lekki, John D.

2013-01-01

The self diagnostic accelerometer (SDA) developed by the NASA Glenn Research Center was tested for the first time in an aircraft engine environment as part of the Vehicle Integrated Propulsion Research (VIPR) program. The VIPR program includes testing multiple critical flight sensor technologies. One such sensor, the accelerometer, measures vibrations to detect faults in the engine. In order to rely upon the accelerometer, the health of the accelerometer must be ensured. The SDA is a sensor system designed to actively determine the accelerometer structural health and attachment condition, in addition to vibration measurements. The SDA uses a signal conditioning unit that sends an electrical chirp to the accelerometer and recognizes changes in the response due to changes in the accelerometer health and attachment condition. To demonstrate the SDAs flight worthiness and robustness, multiple SDAs were mounted and tested on a C-17 aircraft engine. The engine test conditions varied from engine off, to idle, to maximum power. The SDA attachment conditions were varied from fully tight to loose. The newly developed SDA health algorithm described herein uses cross correlation pattern recognition to discriminate a healthy from a faulty SDA. The VIPR test results demonstrate for the first.

GAS CHROMATOGRAPHIC AND SPECTROSCOPIC ANALYSIS OF ...

African Journals Online (AJOL)

Peroxyformic acid prepared in-situ was employed for epoxidation of canola oil in the presence of toluene. Gas chromatographic analysis of the product revealed the following species: C16:0; C18:0; C18:1; C18:2; C18:3; monoepoxy C18:0; monoepoxy C18:1; monoepoxy C18:2; diepoxy C18:0; diepoxy C18:1 and triepoxy ...

Frontline diagnostic evaluation of patients suspected of angina by coronary computed tomography reduces downstream resource utilization when compared to conventional ischemia testing

DEFF Research Database (Denmark)

Nielsen, L. H.; Markenvard, John; Jensen, Jesper Møller

2011-01-01

It has been proposed that the increasing use of coronary computed tomographic angiography (CTA) may introduce additional unnecessary diagnostic procedures. However, no previous study has assessed the impact on downstream test utilization of conventional diagnostic testing relative to CTA in patie...... prospective trials are needed in order to define the most cost-effective diagnostic use of CTA relative to conventional ischemia testing....

Clinical Evaluation of Rapid Diagnostic Test Kit for Scrub Typhus with Improved Performance.

Science.gov (United States)

Kim, Young-Jin; Park, Sungman; Premaratna, Ranjan; Selvaraj, Stephen; Park, Sang-Jin; Kim, Sora; Kim, Donghwan; Kim, Min Soo; Shin, Dong Hoon; Choi, Kyung-Chan; Kwon, Soon-Hwan; Seo, Wonjun; Lee, Nam Taek; Kim, Seung-Han; Kang, Heui Keun; Kim, Yoon-Won

2016-08-01

Diagnosis of scrub typhus is challenging due to its more than twenty serotypes and the similar clinical symptoms with other acute febrile illnesses including leptospirosis, murine typhus and hemorrhagic fever with renal syndrome. Accuracy and rapidity of a diagnostic test to Orientia tsutsugamushi is an important step to diagnose this disease. To discriminate scrub typhus from other diseases, the improved ImmuneMed Scrub Typhus Rapid Diagnostic Test (RDT) was evaluated in Korea and Sri Lanka. The sensitivity at the base of each IgM and IgG indirect immunofluorescent assay (IFA) in Korean patients was 98.6% and 97.1%, and the specificity was 98.2% and 97.7% respectively. The sensitivity and specificity for retrospective diagnosis at the base of IFA in Sri Lanka was 92.1% and 96.1%. ImmuneMed RDT was not reactive to any serum from seventeen diseases including hemorrhagic fever with renal syndrome (n = 48), leptospirosis (n = 23), and murine typhus (n = 48). ImmuneMed RDT shows superior sensitivity (98.6% and 97.1%) compared with SD Bioline RDT (84.4% at IgM and 83.3% at IgG) in Korea. The retrospective diagnosis of ImmuneMed RDT exhibits 94.0% identity with enzyme-linked Immunosorbent assay (ELISA) using South India patient serum samples. These results suggest that this RDT can replace other diagnostic tests and is applicable for global diagnosis of scrub typhus. This rapid and accurate diagnosis will be beneficial for diagnosing and managing scrub typhus.

Addressing Barriers to the Development and Adoption of Rapid Diagnostic Tests in Global Health

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Eric Miller

2015-06-01

Full Text Available Immunochromatographic rapid diagnostic tests (RDTs have demonstrated significant potential for use as point-of- care diagnostic tests in resource-limited settings. Most notably, RDTs for malaria have reached an unparalleled level of technological maturity and market penetration, and are now considered an important complement to standard microscopic methods of malaria diagnosis. However, the technical development of RDTs for other infectious diseases, and their uptake within the global health community as a core diagnostic modality, has been hindered by a number of extant challenges. These range from technical and biological issues, such as the need for better affinity agents and biomarkers of disease, to social, infrastructural, regulatory and economic barriers, which have all served to slow their adoption and diminish their impact. In order for the immunochromatographic RDT format to be successfully adapted to other disease targets, to see widespread distribution, and to improve clinical outcomes for patients on a global scale, these challenges must be identified and addressed, and the global health community must be engaged in championing the broader use of RDTs.

Addressing Barriers to the Development and Adoption of Rapid Diagnostic Tests in Global Health

Directory of Open Access Journals (Sweden)

Eric Miller

2015-06-01

Full Text Available Immunochromatographic rapid diagnostic tests (RDTs have demonstrated significant potential for use as point-of-care diagnostic tests in resource-limited settings. Most notably, RDTs for malaria have reached an unparalleled level of technological maturity and market penetration, and are now considered an important complement to standard microscopic methods of malaria diagnosis. However, the technical development of RDTs for other infectious diseases, and their uptake within the global health community as a core diagnostic modality, has been hindered by a number of extant challenges. These range from technical and biological issues, such as the need for better affinity agents and biomarkers of disease, to social, infrastructural, regulatory and economic barriers, which have all served to slow their adoption and diminish their impact. In order for the immunochromatographic RDT format to be successfully adapted to other disease targets, to see widespread distribution, and to improve clinical outcomes for patients on a global scale, these challenges must be identified and addressed, and the global health community must be engaged in championing the broader use of RDTs.

Addressing Barriers to the Development and Adoption of Rapid Diagnostic Tests in Global Health.

Science.gov (United States)

Miller, Eric; Sikes, Hadley D

Immunochromatographic rapid diagnostic tests (RDTs) have demonstrated significant potential for use as point-of-care diagnostic tests in resource-limited settings. Most notably, RDTs for malaria have reached an unparalleled level of technological maturity and market penetration, and are now considered an important complement to standard microscopic methods of malaria diagnosis. However, the technical development of RDTs for other infectious diseases, and their uptake within the global health community as a core diagnostic modality, has been hindered by a number of extant challenges. These range from technical and biological issues, such as the need for better affinity agents and biomarkers of disease, to social, infrastructural, regulatory and economic barriers, which have all served to slow their adoption and diminish their impact. In order for the immunochromatographic RDT format to be successfully adapted to other disease targets, to see widespread distribution, and to improve clinical outcomes for patients on a global scale, these challenges must be identified and addressed, and the global health community must be engaged in championing the broader use of RDTs.

A weighted generalized score statistic for comparison of predictive values of diagnostic tests.

Science.gov (United States)

Kosinski, Andrzej S

2013-03-15

Positive and negative predictive values are important measures of a medical diagnostic test performance. We consider testing equality of two positive or two negative predictive values within a paired design in which all patients receive two diagnostic tests. The existing statistical tests for testing equality of predictive values are either Wald tests based on the multinomial distribution or the empirical Wald and generalized score tests within the generalized estimating equations (GEE) framework. As presented in the literature, these test statistics have considerably complex formulas without clear intuitive insight. We propose their re-formulations that are mathematically equivalent but algebraically simple and intuitive. As is clearly seen with a new re-formulation we presented, the generalized score statistic does not always reduce to the commonly used score statistic in the independent samples case. To alleviate this, we introduce a weighted generalized score (WGS) test statistic that incorporates empirical covariance matrix with newly proposed weights. This statistic is simple to compute, always reduces to the score statistic in the independent samples situation, and preserves type I error better than the other statistics as demonstrated by simulations. Thus, we believe that the proposed WGS statistic is the preferred statistic for testing equality of two predictive values and for corresponding sample size computations. The new formulas of the Wald statistics may be useful for easy computation of confidence intervals for difference of predictive values. The introduced concepts have potential to lead to development of the WGS test statistic in a general GEE setting. Copyright © 2012 John Wiley & Sons, Ltd.

Publishing nutrition research: validity, reliability, and diagnostic test assessment in nutrition-related research.

Science.gov (United States)

Gleason, Philip M; Harris, Jeffrey; Sheean, Patricia M; Boushey, Carol J; Bruemmer, Barbara

2010-03-01

This is the sixth in a series of monographs on research design and analysis. The purpose of this article is to describe and discuss several concepts related to the measurement of nutrition-related characteristics and outcomes, including validity, reliability, and diagnostic tests. The article reviews the methodologic issues related to capturing the various aspects of a given nutrition measure's reliability, including test-retest, inter-item, and interobserver or inter-rater reliability. Similarly, it covers content validity, indicators of absolute vs relative validity, and internal vs external validity. With respect to diagnostic assessment, the article summarizes the concepts of sensitivity and specificity. The hope is that dietetics practitioners will be able to both use high-quality measures of nutrition concepts in their research and recognize these measures in research completed by others. Copyright 2010 American Dietetic Association. Published by Elsevier Inc. All rights reserved.