PubMed Health⌕ Search

Biomedical subjects

J H Rippey

Publications and source records attributed to J H Rippey.

17 recordsLinked to original sources
PubMed1988

The overall role of a proficiency testing program.

Proficiency testing programs provide many benefits to participant laboratories, functioning as an integral component of total quality control, as a vehicle for self-improvement, as a mechanism for continuing education, and as a fulfillment of regulatory requirements. Proficiency testing should not be utilized as the sole indicator of acceptable laboratory performance; unacceptable results should serve as a trigger for further inquiry and corrective action as indicated. A proficiency testing program should be a broad-based program covering the usual spectrum of laboratory disciplines without commercial bias and it should possess continuous scientific input so as to be capable of adjusting promptly to technologic advancements as well as maintaining established participant benefits. It is important that proficiency testing programs continue to develop mechanisms of mutual interchange with accreditational bodies and regulatory agencies.

Laboratories↗
PubMed1985

Problems in ANA test interpretation: a comparison of two substrates.

Comparison of serum antinuclear antibody (ANA) test results on commercial HEp-2 cell culture preparations and fixed mouse kidney sections demonstrated significant differences in end-point titers and pattern production. When manufacturer's suggested screening titers are used, there is also a significant difference in qualitative results and correlation with clinical status. With individual intralaboratory establishment of screening titer levels, some of these differences become less significant, although this study suggests that mouse kidney substrate slides are more sensitive in detecting nonspecific ANA, and that HEp-2 substrate slides are more specific in detecting ANA from cases of systemic lupus erythematosus. Antinuclear antibody substrate selection must be based on classic sensitivity-specificity considerations and the clinical correlation performance desired. Comparisons of interlaboratory or follow-up ANA results are invalid without consideration of substrate variations. Regardless of substrate utilized, each laboratory should establish its own individual screening titers in relation to suitable age groupings.

Animals↗
PubMed1985

Pretest temperature effects on CAP syphilis serology survey samples.

The College of American Pathologists syphilis serology survey participants periodically question survey-sample stability when the samples have possibly been exposed to temperature extremes during shipment. In this study it was demonstrated that short-term pretest incubations at temperatures above 58 degrees C (136.4 degrees F) usually cause a reduction in both rapid plasma reagin and FTA-ABS reactivity. No reactivity changes occurred in either test with short-term exposures to temperatures between -80 degrees C and 58 degrees C.

Antibodies, Bacterial↗
PubMed1985

Quality assurance and proficiency testing for autoantibodies to nuclear antigen.

The College of American Pathologists' Proficiency Survey results have shown a need for standardization of testing for autoantibodies to nuclear antigens (ANA). We have recommended that each laboratory establish age-adjusted reference ranges for particular methods and instrumentation, report qualitative end point titers in relation to these reference ranges, interpret normal or abnormal as a laboratory appraisal rather than as a clinical assessment, and inclusion of a low-titer ANA control sera in each assay.

Antibody Specificity↗
PubMed1984

Pregnancy tests: evaluation of current status.

During the past 2 decades, laboratorians have observed many changes in pregnancy tests, which are generally defined as procedures designed to detect elevated levels of hCG in urine and/or serum. The original tests were animal assays in which biologic changes were observed following the injection of urine. The currently most widely utilized tests are slide and tube tests, including some of with beta-subunit specificity, in which urine hCG is detected by immunologic antigen-antibody reactions. Finally, in some settings there has been increased testing for hCG by radioreceptor assays based on the binding of hCG to plasma membrane receptor sites and qualitative radioimmunoassay utilizing classic competitive binding techniques. This review compares the relative advantages and disadvantages of these procedures in regard to diagnostic effectiveness, sensitivity, specificity, cost variables, and technical requirements.

Agglutination Tests↗
PubMed1983

Results of tests for rheumatoid factor on CAP survey specimens.

Performances of participants for the detection and measurement of rheumatoid factor on 18 consecutive CAP survey specimens are tabulated. All reagents used by participants performed well qualitatively on the positive and negative specimens. Quantitation of positive specimens by titer and International Units demonstrated prominent interlaboratory variance.

Humans↗
PubMed1982

Performance on immunoglobulin IgG, IgA, and IgM tests in CAP survey specimens.

The performance of participants in nine consecutive College of American Pathologists (CAP) Survey specimens during 1979-1981 are listed for IgA, IgG, and IgM. The majority of participants used either radial immunodiffusion (RID) (51.4%) or nephelometric kits (33.6 per cent) manufactured by major firms and reported results in mass units (93.5 per cent). When tabulated by kit, prominent differences in performance were noticed. Furthermore, definite trends in methods employed were evident during the two-year period.

Humans↗
PubMed1981

Cell typing in lymphoproliferative disorders. Use of a sensitive hemadsorption technique for sections of normal and abnormal lymphoid tissue.

We have adapted a hemadsorption technique originally devised to detect Fc receptors on human cancer cells for categorizing different lymphoid cells in frozen sections of normal and abnormal human biopsy specimens. The procedure is sufficiently sensitive to demonstrate T-lymphocytes and receptors on the cells in diffuse non-Hodgkin's lymphomas in sections which has been difficult, if not impossible, using other techniques. It demonstrates the expected distribution of B- and T- lymphocytes and mononuclear phagocytes in normal lymphoid organs. When used to type the cells of non-Hodgkin's lymphomas, it furnishes results comparable to more tedious methods requiring cell separation: 63 of 74 non-Hodgkin's lymphomas were classified as neoplasms of B-cells. In 16 cases of Hodgkin's disease of the nodular sclerosis and mixed cellularity types, all major classes of lymphoid cells were present. The proliferating cells were typed as B-cells in four cases of immunoblastic lymphadenopathy.

Adult↗
PubMed1981

Performances of urine pregnancy tests on College of American Pathologists Survey specimens.

The participant performances on the College of American Pathologists (CAP) Urine Survey specimens distributed during 1979 and 1980 for pregnancy testing are reviewed. Almost all the reagent methods used by the participants performed well on the negative specimens. Prominent differences in results on the positive specimens were found. Awareness by laboratorians of the reagent sensitivity, limitations, and capabilities of commercial tests for determining human chorionic gonadotropin in urine is recommended.

Chorionic Gonadotropin↗
PubMed1980

Rheumatoid factor test performance on CAP survey specimens.

The participant performances on 1979 rheumatoid factor test survey specimens are tabulated. All reagents performed well on the qualitative positive and negative specimens. Prominent differences in results occurred with the weakly positive specimen. Some reagents consistently gave higher titers on the positive specimen, indicating the need for reference standards.

Agglutination Tests↗
PubMed1979

Infectious mononucleosis test performance on CAP survey specimens.

The participant performances on 1977 and 1978 infectious mononucleosis survey specimens are tabulated. The various methods utilized gave similar results on negative specimens. Commercial reagent kits incorporating differential absorption performed somewhat better on positive specimens than kits without differential absorption. Many of the commercial reagent kits performed very poorly on the false postitive specimen.

Antibodies, Viral↗