Inter-assayStandardizationCalibratorsSensitivityImmunoprecipitationELISASpecificityVariationsMeasurementCohortOptimalDifferencesGuidanceTherapeutic rangeMolecularClinicalSamplesFactorsTestLaboratorySensitiveStudyReferenceValuesWide rangeResultsLackFindingsDetectionResearchStudiesStandardPreviousConditionsCommercialSpecificValidationIssue
Inter-assay4
- WHO 07/202 and serum pools were used for instrument/assay and mathematical recalibration, respectively, to determine if their use decreases inter-assay measurement variability for clinical samples. (cdc.gov)
- Non-C37 and C37 serum pools were commutable for all 6MPs assessed and decreased inter-assay variability from 208 to 13.8% and 4.6%, respectively, when used for mathematical recalibration. (cdc.gov)
- CONCLUSIONS: All materials evaluated, when used as common calibrators, substantially decreased inter-assay sTfR measurement variability. (cdc.gov)
- Inter-assay and intra- about 4.4 million people, had impaired disorders such as hypo- or hyperthy- assay variations for PTH were 8.9% and fasting glucose [2,3]. (who.int)
Standardization3
- From this, Zetterberg concluded that the assays needed to improve before they were ready for standardization, and for the subsequent applied research that moves tests beyond research-grade toward clinical chemistry certification and from there to doctors' offices around the world. (alzforum.org)
- Clearly, we need standardization in all hormone assays. (medscape.com)
- OBJECTIVES: The clinical use of soluble transferrin receptor (sTfR) as an iron status indicator is hindered by a lack of assay standardization and common reference ranges and decision thresholds. (cdc.gov)
Calibrators1
- As each study had used different assays for measuring testosterone, with each assay using different calibrators, the team obtained fasting morning serum samples from 100 men in each cohort, which were then analyzed in the CDC Clinical Reference Laboratory using a single, highly calibrated assay. (medscape.com)
Sensitivity6
- There's a lot of political talk that the tiny and decreasing number of women in computing is a result of sexism and prejudice that has to be remedied with measures ranging from sensitivity training up through admission and hiring quotas. (ibiblio.org)
- In summary, 1) the assay standard curves and the relative signals of the calibrator concentrations were consistently within the criteria specified by the manufacturer, 2) the obtained assay sensitivity was calculated to be 4.33 pg/mL while the manufacturer claimed sensitivity was 6.15 pg/mL, 3) two samples with very high and high Klotho concentrations were used at different dilution to evaluate the assay linearity. (cdc.gov)
- The assay sensitivity was 6 pg/mL. (cdc.gov)
- There are a number of factors that can be altered to obtain optimum assay performance and thereby lead to higher molecular sensitivity, specificity and precision. (sigmaaldrich.com)
- Whenever primer dimer products are produced and amplified, they divert reaction components away from synthesis of the desired product, thereby reducing assay efficiency and sensitivity. (sigmaaldrich.com)
- Unfortunately, existing field assay methods are typically inadequate because they lack the selectivity and sensitivity needed to provide reliable information. (cdc.gov)
Immunoprecipitation2
- These antibodies can be utilized over an extensive application range including Flow Cytometry, Immunohistochemistry, Western Blot, Immunoprecipitation, ELISA, ELISpot and Biological assays. (diaclone.com)
- Two immunoprecipitation-mass-spectrometry assays came out on top, accurately pegging people who had plaques 83 to 87 percent of the time. (alzforum.org)
ELISA2
- the other two use the Elecsys platform or an enzyme-linked immunosorbent assay (ELISA). (alzforum.org)
- Next was the N4PE Simoa (brown) and Euroimmun ELISA immunoassay (gray), followed by a U Gothenburg IP-MS (green) and Quanterix Simoa (red) assays. (alzforum.org)
Specificity3
- Assays requiring high specificity are particularly vulnerable when performed without optimization and adequate controls. (sigmaaldrich.com)
- With dye-based detection such as SYBR Green I, primer dimers also affect assay specificity because the nonspecific DNA-binding dye will bind to the primers and be detected along with the desired product. (sigmaaldrich.com)
- The specificity of the assay is confirmed by a panel of clinically relevant non-MTB bacteria, and the clinical utility is demonstrated by the measurements in MTB-positive patient specimens. (cdc.gov)
Variations1
- While highlighting that the findings establish a reference range for testosterone, he added: "These data also show that variations in assays are an important contributor to variation in testosterone levels in cohorts from different geographic regions. (medscape.com)
Measurement1
- Due to its concentration in picomolar range and the delicate equilibrium of free and protein-bound T4, accurate measurement is challenging. (cdc.gov)
Cohort2
- The assays ranked in the same order in a validation cohort of 51 cognitively normal, 51 MCI, and 20 AD dementia samples from the Alzheimer's Disease Neuroimaging Initiative. (alzforum.org)
- Harmonizing testosterone levels from four major cohort studies, Shalender Bhasin, MD, from Brigham and Women's Hospital, Harvard Medical School in Boston, Massachusetts, and colleagues were able to identify a reference range for testosterone that could help clinicians in decision making and improve patient care - this was in the region of 250 to 900 ng/dL for 19- to 39-year-old men. (medscape.com)
Optimal3
- However, all assays have a set of optimal conditions and these are dependent on the instrument, selected reagents (buffer conditions), primer concentration and/or annealing temperature (T a ), magnesium concentration and even ramp rate. (sigmaaldrich.com)
- However, the widespread application of RT-QuIC has been hampered by 1) the lack of well-characterized reference samples to ensure proper assay functioning, identify optimal tissues for ante-mortem sampling, and determine biological relevance of results and 2) the absence of an appropriate modeling framework to leverage the information produced by RT-QuIC. (usgs.gov)
- The availability of reference samples and a robust modeling framework for CWD diagnostic labs and managers will help promote the rigorous application of RT-QuIC, identify optimal tissues for ante-mortem sampling, assess biological relevancy of findings, and provide a mechanism to leverage RT-QuIC information to aid CWD control efforts. (usgs.gov)
Differences1
- This is a bit lower than in previous studies on these assays, showing that differences in cohorts and sample handling influence test results. (alzforum.org)
Guidance2
- The primer design can be reviewed with respect to the assay design guidance provided in PCR/qPCR/dPCR Assay Design . (sigmaaldrich.com)
- This document has been developed by CDC to give guidance to laboratories performing lymphocyte immunophenotyping assays in human immunodeficiency virus-infected persons. (cdc.gov)
Therapeutic range1
- To ensure continuous anticoagulation when converting from heparin sodium to warfarin, continue full heparin therapy for several days until the INR (prothrombin time) has reached a stable therapeutic range. (pfizermedicalinformation.com)
Molecular3
- Potency is determined by means of a biological assay and interpreted by the first International Low Molecular Weight Heparin Standard as units of anti-factor Xa (anti-Xa) activity per milligram. (rxlist.com)
- The average molecular weight ranges between 5,500 and 7,500 daltons. (rxlist.com)
- Most recently, GeneXpert MTB/RIF (Cepheid) advanced nucleic acid-based detection by integrating PCR and a highly sensitive molecular-beacon assay into a single, automated system. (cdc.gov)
Clinical1
- Well-defined reference ranges are at the heart of clinical practice and, without them, clinicians can make erroneous diagnoses that could lead to patients receiving costly, lifelong treatments that they don't need or deny treatments to those who need them," said Dr Bhasin said in an Endocrine Society press release. (medscape.com)
Samples2
- The reference ranges evaluated in 114 samples from apparently healthy donors indicated the alpha-Klotho levels ranged from 285.8 to 1638.6 pg/mL with a mean of 698.0 pg/mL. (cdc.gov)
- Claims relating to the performance of assays should be verified under the conditions of the study, including test samples, specific reagents and the instrument of choice. (sigmaaldrich.com)
Factors4
- Spectrophotometric methods were used to assay the clotting factors II, VII, IX and X in plasma of 33 subjectively healthy human donors and in plasma of 98 patients receiving long-term oral anticoagulant therapy. (karger.com)
- Plasma from 98 patients receiving long-term anticoagulant therapy was assayed with 'Thrombotest', a clotting test in whole blood introduced by Owren and in these plasmas the activity of each of the vitamin K-dependent factors was assayed with spectrophotometric methods. (karger.com)
- For the clotting factors IX and VII, novel spectrophotometric methods were applied and the plasma activities thus measured were compared to results obtained with factor IX and VII clotting assays. (karger.com)
- however, several factors have a profound effect on the reliability of FT4 assays and require special consideration. (cdc.gov)
Test3
- The biological test system was a consortium of microorganisms common to the activated sludge treatment process. (europa.eu)
- Control, reference, and treatment test mixtures were incubated at temperatures ranging from 21.6 to 22.2 °C and aerated for three hours at a rate sufficient to provide aerobic conditions and maintain solids in suspension. (europa.eu)
- Gen-Probe RNA test, interferon-gamma assay, urine-based antigen test). (cdc.gov)
Laboratory2
- Assays purchased from skilled commercial providers still require validation within the laboratory in which they are being used. (sigmaaldrich.com)
- The development of the real-time quaking-induced conversion (RT-QuIC) assay has the potential to transform laboratory research of prions and provide new opportunities for improved surveillance and management. (usgs.gov)
Sensitive3
- Optimization is required to ensure that the assay is as sensitive as is required and that it is specific to the target of interest. (sigmaaldrich.com)
- DCM assays were sensitive enough to separate workers exposed to 10 ppm from non-exposed workers. (who.int)
- Combined with portable systems, the magnetic barcode assay holds promise to become a sensitive, high-throughput, and low-cost platform for point-of-care diagnostics. (cdc.gov)
Study1
- Harmonized reference normal ranges for testosterone levels in healthy, nonobese men have been generated in a landmark study that should aid in accurately diagnosing hypogonadism , say US investigators. (medscape.com)
Reference2
- He emphasized that it is important that the new reference range for testosterone be taken "into consideration in the tests that clinicians and patients depend on for accurate diagnoses. (medscape.com)
- As testosterone levels decline with age, the researchers initially generated reference ranges in healthy, nonobese men aged 19 to 39 years, followed by ranges stratified by decade of age. (medscape.com)
Values1
- Age and assay variation values for 25(OH)D from the third national Surveil ance of sex were matched between the 2 groups. (who.int)
Wide range2
- An assay that has been designed such that all desirable design criteria were met ( PCR/qPCR/dPCR Assay Design ) is likely to perform well under a wide range of conditions. (sigmaaldrich.com)
- To meet this need, a wide range of field screening methods for identifying chemical, biological, and nuclear materials is presently being marketed and used. (cdc.gov)
Results2
- In collaboration with the University of Wisconsin, state and federal partners, the USGS National Wildlife Health Center (NWHC) is working to fill these gaps by using RT-QuIC to fully characterize a range of biological tissues, body fluids, and excreta that are CWD-positive and -negative and comparing those results against the gold standard animal bioassay (a transgenic mouse bioassay). (usgs.gov)
- The results show that the field has reduced variation within each assay to create better tests," co-author Henrik Zetterberg, University of Gothenburg, Sweden, told Alzforum. (alzforum.org)
Lack1
- However, the task is made more difficult by a lack of both defined references ranges for testosterone and standardized assays. (medscape.com)
Findings2
- They say their findings underline the variable performance of hormone assays. (medscape.com)
- The new findings, which are based on measurements taken from over 9000 men and calibrated against a US Centers for Disease Control and Prevention (CDC) standardized assay, offer, for the first time, a reliable baseline for total testosterone levels. (medscape.com)
Detection1
- Diaclone Monoclonal Antibodies are highly specific, high quality mouse monoclonal antibodies for the detection of a broad range of human proteins. (diaclone.com)
Research1
- Validation provides the data required to justify the continued use of the assay in further research projects 1 . (sigmaaldrich.com)
Studies1
- Three studies of DCM-exposed workers (ranging from 20 to 96 workers) have reported a positive correlation with urinary DCM (although small amounts) and time- weighted average DCM in the breathing-zone air of the workers (reviewed by Imbriani and Ghittori, 2005). (who.int)
Standard1
- Since it is usual to run the assay on a selected instrument and under standard buffer conditions, most optimization procedures are focussed on modification of primer binding kinetics using primer concentration or annealing temperature (T a )/melting temperature (T m ). (sigmaaldrich.com)
Previous1
- Validation of primer design is particularly important when adopting primers from a previous publication or using a commercially supplied assay. (sigmaaldrich.com)
Conditions2
- Similarly, when multiple targets are to be detected simultaneously in multiplex reactions, assay conditions must be optimized to detect all targets equally. (sigmaaldrich.com)
- DCM is very volatile and thus sampling and storage conditions of biological fluids are important. (who.int)
Commercial1
- Chronic wasting disease (CWD) has been detected in 31 US states and four Canadian provinces in free-ranging cervids and/or commercial captive cervid facilities. (usgs.gov)
Specific1
- There are no Klotho specific cut-points to be used as indicators of biological age. (cdc.gov)
Validation1
- Assay optimization and validation are essential, even when using assays that have been predesigned and commercially obtained. (sigmaaldrich.com)
Issue1
- This is a key issue for circumstances ranging from responding to terrorist attacks to monitoring the effects of environmental remediation. (cdc.gov)