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PubMed1990

Stress and blood glucose in type II diabetes mellitus.

Six adults with non-insulin dependent diabetes mellitus participated in a laboratory procedure to determine the effects of an acute stressor, mental arithmetic, on blood glucose, cardiovascular, and subjective indices of stress. They then completed 12 days home monitoring of stressful events, subjective stress, and blood glucose. Diet and activity were controlled to evaluate the direct effects of stress on blood glucose in the natural environment. Laboratory results showed significant increases in blood glucose, cardiovascular (HR and SBP), and subjective stress ratings during the mental arithmetic task when compared to a resting condition. Home monitoring data were consistent with the laboratory findings; blood glucose range tended to be greater on high vs low stress days, especially when the difference between high and low stress was greatest. These findings suggest that the laboratory stress induction procedure was externally valid and that in the natural environment, stress has a hyperglycemic effect on blood glucose.

Arousal↗
PubMed1993

Comparison of a standardized procedure with current laboratory practices for the detection of lupus anticoagulant in France. Working Group on Hemostasis of the Société Française de Biologie Clinique.

A multicenter study involving 13 laboratories was designed to compare a common procedure for screening lupus anticoagulants (LA) to the different practices currently in use in these laboratories. The common procedure combined 3 phospholipid-dependent assays, including mixing studies and a phospholipid neutralizing test. Due to the heterogeneity of LA expression, an abnormal result in at least one of the tests was sufficient to classify a sample as positive for LA. Consecutive samples referred for LA diagnosis were evaluated in parallel by each participant and the data found using the common procedure were analyzed independently according to mutually agreed cut-offs and criteria for sample classification. Within a period of 3 months, 535 samples were included, of which 147 were judged LA positive, 29 undetermined and 359 negative by the respective laboratories using their current practice. When using the common procedure, 149 plasmas were said to be positive, 38 undetermined and 348 negative. Absolute concordance occurred for 81% of the specimen population and absolute discordance (positive versus negative) for 7%. The level of agreement between the common procedure and the current practices, assessed by kappa indexes, indicated noticeable variations in the rates of detection from laboratory to laboratory. Among the different tests used in the common procedure, regular APTT was the least sensitive (about 50% detection) but none of the other tests alone recognized more than 73% of specimens from the LA positive population. This yield increased to about 90% with any combination of 2 sensitive tests.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Coagulation Tests↗
PubMed1981

Three-pool analysis for quality control: a method for daily differentiation of analytic error from random variability.

Using the Z statistic we have devised a novel, mathematically simple concept for daily quality control of laboratory procedures. The method allows rapid identification and differentiation of systematic errors from random variability on a daily basis, increases confidence in the accuracy of reported results, reduces the number of repeat analyses, and allows the analyst to detect a deteriorating quality control pool. Using three controls instead of one or two increases the chance of detecting out-of-control situations and uses simplified statistical calculations summarized on a single graphic wall chart to monitor the daily accuracy and precision of analytic procedures. The method is adaptable to any type of specimen quantitatively analyzed and can be used in large or small laboratories with light or heavy workloads. This paper reflects what happens in a small laboratory with only one run each day, but, the system has been tested in a large community hospital with a heavy workload and multiple runs each day. Although this procedure is presented for the clinical laboratory, the method would be equally useful in industry.

Laboratories↗
PubMedDate not supplied

Acquisition of endovascular skills for obstetrician-gynecologists.

STUDY OBJECTIVE: To identify skills not part of the training of obstetrician-gynecologists that are needed to perform endovascular procedures, especially uterine artery embolization. DESIGN: Literature review of known skills necessary to perform endovascular procedures. RESULTS: Important areas of endovascular skills are as follows. Understanding of the modern C-arm image intensifier is basic to performing endovascular procedures safely for the patient, physician, and others in the procedure room. Many states require physicians to obtain a Fluoroscopy Supervisors Permit when doing such interventions. Arteriotomy begins every endovascular procedure. Physicians must understand catheter manipulation and selection, and the use of microcatheters. An understanding of the pelvic arterial anatomy will help the surgeon identify the uterine arteries. Once in the uterine artery, the surgeon must understand how to successfully embolize the artery. As in any surgery, prevention of complications is important as well as management of complications once they arise. CONCLUSION: Obstetrician-gynecologists should plan on devoting a year for the acquisition of skills needed to perform endovascular procedures. Methods of acquiring such skills include simulator training, animal laboratory procedures, and observation of live procedures. Didactic courses will give physicians an overview of endovascular procedures.

Balloon Occlusion↗
PubMed1999

Quality and safety aspects of reusable plastic food packaging materials: a European study to underpin future legislation.

The objective of this study was to develop a comprehensive package of quality assurance criteria for use by industry and regulatory authorities for ensuring the quality and safety-in-use (sensory, microbiological and chemical) of reused plastics for food packaging. The study included thermal degradation effects, flavour carry-over caused by flavour and off-flavour substances, the influence of washing processes on the materials, and the efficiency of washing processes in removing off-flavour substances and surrogate substances representing misuse chemicals as might be put in bottles by consumers. The microbial safety of the refillable plastic articles in relation to commercial washing processes and the industrial procedures applied has also been investigated. Lastly, the suitability of laboratory procedures using strips of bottle material for predicting the sorption and washing properties of refillable plastic bottles has been studied. In general it is concluded that reuse of the articles does not significantly influence any of the properties investigated. Neither the chemical, physical nor surface properties seem to be significantly influenced by repeated washing. It can be concluded, however, that it is very likely that most of the articles investigated will cause flavour carry-over to a new filling if they are contaminated with strongly flavoured products. Finally it can be concluded that the procedures evaluated can serve as a basis for future legislation on refillable articles, but for several procedures (like quick predictive testing with strips) more investigation is required to create a more solid basis.

Equipment Reuse↗
PubMed1993

Evaluation of sputum smears concentrated by cytocentrifugation for detection of acid-fast bacilli.

Early identification and isolation of tuberculosis patients is of utmost importance to minimize the risk of further epidemic spread of the disease. The traditional concentrated acid-fast smears are not very reliable tools for the presumptive diagnosis of tuberculosis. Acid-fast bacillus (AFB) smears from 120 patients specimens and 80 simulated AFB samples were processed according to standard laboratory procedures and by cytocentrifugation (Cyto-Tek, Ames Division, Miles Laboratories, Inc., Elkhart, Ind.). Prior to dispensing of samples into the Cyto-Tek chambers, specimens were liquefied and decontaminated by mixture with an equal volume of 5% sodium hypochlorite (household bleach). Culture and smear results were correlated. Of 120 patient specimens, 43 were culture and smear negative by both methods. Ten specimens were overgrown with mold and bacteria, but 2 of them had positive AFB smears by cytocentrifugation only. There were 67 positive AFB cultures, with 67 positive cytocentrifuge smears and 34 positive smears by the conventional technique. Of the 80 simulated positive AFB samples, all grew mycobacteria on culture. Smears from the 10(5)- to 10(3)-CFU/ml specimens were positive by both methods. The simulated samples with 10(2) CFU/ml yielded smears positive only by cytocentrifugation. The Cyto-Tek AFB smears had a greater correlation with positive culture than did the smears from concentrated specimens. The sensitivity, efficiency, and rapidly of the Cyto-Tek AFB smear technique resulted in increased detection of mycobacteria in clinical specimens. The simplicity and safety of this method will enable qualified mycobacteriology technologists to rapidly and accurately perform sputum smears for AFB at clinics, emergency rooms, and field sites, as well as in the traditional laboratory setting.

Centrifugation↗
PubMed2000

A study on task-analysis of clinical pathologists as medical consultants in Nihon University Hospital--a Japanese perspective by comparison with current status in the USA.

To identify our role and the customers' satisfaction, the on-call consultation service records of the Department of Clinical Pathology, Nihon University School of Medicine, Itabashi Hospital (NUIH), were analyzed. Between 1995 and 1998, 1,789 consultation services were recorded, and approximately 40% were from physicians, and 50% were from medical technologists. During office hours, many physicians made contact with us at the office of clinical pathology, the clinical laboratory and other places in the hospital by various means. They asked us to interpret multidisciplinary laboratory data, and to provide the specific information that might affect clinical management. Medical technologists asked for clinical information of patients with extreme measured values and requested that we contact with physicians. In contrast, on weekends/holidays or after routine working hours, physicians sometimes requested non-automated laboratory tests such as peripheral blood smears/bone marrow smears or Gram stains. The major contents of our responses to medical technologists were concerned with blood banking and handling of instruments not to be operated in routine work. These results reconfirm that we are still required to have clinical competence for common laboratory procedures and to have the capability of interpretation of multidisciplinary laboratory data in the university hospital. Traditionally, most Japanese clinical pathologists have been focused their attention on bench work in research laboratories. However, the present study shows that the clinical pathologists need to bridge the real gap between laboratory technology and patient care. Our on-call service system can enhance the education of clinical pathologists, and improve not only laboratory quality assurance but also patient care. In addition, in response to a need for customer access to this service with a shortage of clinical pathologists, a more effective method would be to set up a proactive systemic approach in a more rigorous academic environment adopting advances in medical informatics.

Consultants↗
PubMed1992

Fungal keratitis.

As Jones has emphasized, the successful management of microbial keratitis, fungal or otherwise, necessitates five steps: (1) clinical suspicion and clinical diagnosis; (2) performing the proper laboratory procedures; (3) initiating antimicrobial therapy based on the results of laboratory studies; (4) modifying the initial therapy based on the clinical response; and (5) deciding correctly when and how to terminate therapy. Keratomycosis poses special diagnostic and therapeutic challenges for ophthalmologists because of its low incidence, and its resistance to treatment, because of the lack of antifungal agents with good penetration into the eye, and because of the difficulties in obtaining meaningful in vitro drug susceptibility results for fungal isolates. We believe, however, that ophthalmologists are now diagnosing keratomycosis earlier and treating it more effectively.

Antifungal Agents↗
PubMedDate not supplied

Quantitative analysis of limonin in grapefruit juice using an enzyme-linked immunoassay: interlaboratory study.

Eleven laboratories participated in an interlaboratory study of an enzyme-linked immunoassay for limonin in grapefruit juice. Participating laboratories received training and practice samples until familiar with the procedure. Laboratories then received 8 sample pairs of grapefruit juice as blind duplicates. Samples were refrigerated and analyzed within 4 days of receipt. Results from 1 laboratory and 6 individual samples were excluded from the statistical analysis. Method performance was measured by the one-way component of variance analysis. Repeatability relative standard deviations (RSDr) ranged from 7.0 to 15.6%. Reproducibility relative standard deviations (RSDR) ranged from 12.9 to 29.4%.

Beverages↗
PubMed1979

Standardization of measures prior to cluster analysis.

A common problem in cluster analysis is the determination of a scale-free measure of distance between individuals. This paper presents a procedure for scaling measurements using a reference individual as a standard of comparison. The procedure is particularly useful in classification of the results of laboratory procedures, where a reference standard is routinely produced. An example is the clustering of patterns that result from crossed antigen-antibody electrophoresis for determining the phenotype of the serum protein alpha 1-antitrypsin. The procedure appears to remove extraneous variability while retaining the information necessary for classification.

Blood Protein Electrophoresis↗
PubMed1982

Laboratory testing in the office of family physicians.

A survey of family physicians was carried out among members of the state academies of family practice and graduates of residency programs in Ohio and North Carolina. Results of the survey demonstrated both an increasing number of laboratories in the offices of all family physicians as well as in increasing variety of laboratory procedures offered. It was found that solo practitioners frequently perform laboratory work themselves, while group practitioners more often delegate laboratory work to other office staff, such as certified laboratory technicians or nurses. Quality control was offered in one-half of the private offices surveyed, and in three-quarters of the office that employed certified laboratory technicians. Results of this study suggest that the increasing number of family practice residency graduates may result in an increased demand for certified laboratory technicians in private office laboratories.

Clinical Laboratory Techniques↗
PubMed1977

A rapid, inexpensive, infrared screening method for elevated serum triglycerides.

The application of infrared absorption spectrophotometry to the mass screening of human serum for elevated triglyceride levels has been investigated, and results in both normal and elevated ranges have been compared with values obtained by manual and automated procedures. By means of a simple technique serum samples were scanned with a typical instrument, and the difference in absorbance at 1,740 and 1,725 cm-1 was plotted vs. triglyceride concentration to prepare a Beer-Lambert plot; several hundren serum samples were then determined with the plot, and results were compared with those from two independent methods with good agreement. Significantly elevated serum cholesterol ester levels gave high values, but this was not considered a disadvantage in view of the general screening nature of the determination. The standard deviation at 160 mg/dl was found to be 13. The infrared method is presented at a viable mass screening procedure; it is not proposed that it supplant presently available laboratory procedures for routine use at this time. Advantages of the infrared method include simplicity, rapidity, low supply cost per test, and small sample volume.

Cholesterol↗
PubMed1997

[A time study in a department of histopathology].

In the Department of Histo- and Cytopathology, Herlev University Hospital, Copenhagen, a time study was performed according to the principles known from work sampling. From 22.11-12.12.1993 laboratory technicians, pathologists and secretaries were interviewed and an activity form was filled in. Six thousand nine hundred and fifty interviews were performed and the time study showed that for all groups of personnel 40% of the time was used on specimens sent for microscopy, 5% on autopsies (excl. microscopy), 15% on teaching and research, 20% on scientific meetings, reading and administration and 20% on other activities e.g. lunch, holiday, absence owing to illness. There was little variation for the different groups of personnel. On the other hand the time used on specific laboratory procedures, e.g. serial cutting, special-, and immunostaining, varied considerably for laboratory technicians, pathologists and secretaries respectively. Time studies, especially "work sampling" yield important information for the planning of laboratory services and provide documentation also for the time not directly related to routine work.

Denmark↗
PubMed1998

Analytical evaluation of an improved procedure for measuring thyrotropin.

The analytical characteristics of the AxSYM Ultrasensitive hTSH-II (Abbott Laboratories) procedure for quantitation of serum thyrotropin (TSH) concentration were evaluated. Within- and between-run imprecisions, functional sensitivity, analytical interval and relative inaccuracy with respect to the Enzymum-Test TSH (Boehringer Mannheim) were studied. In all cases, the within-run and between-run of coefficients variation were lower than 6.69% and 8.12% respectively. The measurement range was tested with serial dilutions of a serum with a high thyrotropin concentration, and the procedure was found to be linear up to at least 87.0 mIU/l. The functional sensitivity was 0.018 mIU/l. The relative inaccuracy study (Passing-Bablok non-parametric linear regression) produced the following linear equation: (AxSYM) = 1.02. (ES-700)-0.03 mIU/l, with 95% confidence intervals of a (-0.05; -0.01); b (0.98; 1.06).

Humans↗
PubMed2003

[Practical advice for recovery and successful processing of anterior chamber puncture and vitrectomy samples].

For the diagnosis of unclear intraocular inflammation which threatens visual acuity and does not respond to therapy, the collection of intraocular fluid from the anterior chamber or the vitreous body is sometimes required. After surgery the correct and speedy processing of the rapidly degrading fluid determines the quality and reliability of the laboratory results. This article describes the different steps which are important after surgery to ensure optimal results for the different diagnostic laboratory procedures. If specimens are to be sent to cytology or microbiology laboratories, processing directly after surgery is necessary, while material which has to undergo PCR analysis, should remain untreated.

Biopsy↗
PubMed1993

Microwave processing for denture relines, repairs, and rebases.

The microwave processing procedure has been shown to be an efficient and accurate method of polymerizing poly(methyl methacrylate) resin for the fabrication of dentures. This article describes procedures to expand the uses of the microwave technique. With standard laboratory procedures, the microwave technique can improve and simplify denture relines, repairs, and rebasing of partial dentures.

Denture Rebasing↗
PubMed2003

Distinct heterogeneity of IgG immune response in cerebrospinal fluid (CSF) detected by isoelectric focusing (IEF) with extended immunofixation.

An optimized automated IEF procedure in polyacrylamide micro gels and immunofixation with 10 monospecific antibodies against some fragments of the IgG molecule and against the whole IgG isotypes IgG(1), IgG(2), IgG(3), IgG(4), respectively, detected oligoclonal bands (OBs) within acid, neutral, and alkaline ranges of the gels. Accuracy and reliability of the OB assay for detection of an intrathecal IgG synthesis proved to be higher with immunofixation than with silver staining of bands precipitated by trichloroacetic acid. CSF OBs were specified as lambda or kappa IgG subfractions, respectively, duplex IgGs precipitated with anti-lambda, anti-kappa, and anti-Fc antibodies at the same pI. Most of OBs were classified as belonging to either IgG(1), IgG(2), IgG(3), or IgG(4) isotypes in CSF. The IEF procedure additionally allowed the discrimination of both free light chains and possible "free" heavy gamma chain fragments in CSF, when immunofixation was done with monospecific antibodies against both light chains and gamma chain fragments (e.g. anti-F(ab')(2), anti-Fd, anti-Fc, anti-C(H)2). The results pointed out a distinct heterogeneity of the IgG immune response in human CSF. The IEF procedure with extended immunofixation is recommended for completion of the basic laboratory procedures used in neuroimmunology in order to discriminate inflammatory processes in human CNS.

Acrylic Resins↗