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PubMed1974

Observer variation and quality control of cytodiagnosis.

The aim of quality control of a laboratory investigation is to ensure that similar results are obtained on the same material at different centres. To investigate its practicability in cytodiagnosis, the same cytological material was examined independently at six centres. Each centre supplied material from 20 cases, providing a total of 120 cases, ie, 100 cases excluding the donor centre's own material. The degree of agreement between the centres was studied using (a) the standard National Health Service cytology report terminology, (b) the centre's own terminology, and (c) the recommended recall time. The results revealed close agreement between five out of six centres in the reports obtained in relation to dysplasia and malignancy, namely, less than 3% false negative results and not more than 1.7% false positive results. The recommended recall time provided a similar order of agreement after discrepancies due to the management of inflammatory conditions had been eliminated. There was marked disagreement in the diagnosis of both presence and type of infection. The results indicate that improvement in the quality of cytological material would increase the consistency of cytodiagnosis. Cytodiagnosis itself, being an expression of opinion, does not appear to be an appropriate field for quality control.

Candida albicans↗
PubMed1982

Respiratory cytodiagnosis: study in observer variation and its relation to quality of material.

Sensitivity and accuracy of cytodiagnosis were assessed in a multicentre study. Six centres each provided sputum cytological material from 20 cases. Each centre screened and reported on the 100 slides provided by the other five centres. The reports were assessed against consensus reference diagnoses, reached by discussion with transparencies, histological sections, and closed-circuit television. False positive rates of 0-4% (average 1.3%) and false negative rates of 0-12% (average 5.0%) of slides examined were recorded. The order of agreement on the three common cell types was adenocarcinoma 75% (50-91%), squamous cell carcinoma 80% (59-94%) and small carcinoma 95% (71-100%). The effect of quality of material on cytological opinion was assessed by comparing disagreement rates on each of the different sets of 20 slides. Disagreement varied from 1% to 23% depending on which set of material was examined.

Adenocarcinoma↗
PubMed1992

Stigma variations: observations on suppressor T cells and leprosy.

Few areas of immunology have been so controversial as that of suppressor T cells. Studies of T cell clones derived from patients with infectious diseases, including leprosy, and allergies have allowed the delineation of functional human T cell subsets. Both CD4 and CD8 cells can be discriminated into subsets that are differentiated by their functions and patterns of lymphokines. Type 1 CD4 cells reactive with lepromin and PPD produce IFN-gamma and IL-2 predominantly, while Type 2 CD4 clones, specific for tetanus toxoid, produce IL-4 and IL-5. Type 1 CD8 cytotoxic T lymphocytes produce predominantly IFN-gamma and IL-2. T suppressor clones derived from immunologically unresponsive lepromatous leprosy patients are antigen-specific, CD8 cells, HLA-DQ restricted, and produce predominantly IL-4, and were designated Type 2 CD8 cells. Several models for peripheral tolerance based on distinct functional T cell subsets are discussed. Previous models of T cell suppression in the mouse and the reciprocal relationship between humoral and cell-mediated immunity in general are reinterpreted in light of such T cell subset interactions.

Animals↗
PubMed2000

Space flight is associated with rapid decreases of undercarboxylated osteocalcin and increases of markers of bone resorption without changes in their circadian variation: observations in two cosmonauts.

BACKGROUND: Microgravity induces bone loss by mechanism(s) that remain largely unknown. METHODS: We measured biochemical markers related to bone remodeling in two cosmonauts before, during, and after 21- and 180-day space flights, respectively. RESULTS: During both flights, type I procollagen propeptide and bone alkaline phosphatase decreased as early as 8 days after launch. Undercarboxylated osteocalcin percentage increased early and remained high during both flights. Vitamin K supplementation restored carboxylation of osteocalcin during the long-term flight. Urinary and serum C-telopeptide of type I collagen (CTX) increased as early as day 8 of the flights; the increase was greater in serum than in urine. Pyridinoline, free deoxypyridinoline, and N-telopeptide increased less than CTX during the short-term space flight. The circadian rhythm of bone resorption assessed by urine CTX and free deoxypyridinoline was not altered by microgravity. CONCLUSION: Vitamin K metabolism or action and bone remodeling may be altered in cosmonauts.

Adult↗
PubMed2001

Variations observed during a 1999 dissection course--their sum and analysis.

A systematic study of anomalies in all body areas of 12 male and 12 female cadavers was attempted from data obtained during a 1999 dissection course. A total of 229 anomalies (132 in males, 97 in females) were observed, and they were comprised of 142 varieties. Classified by system, there were 71 (45 varieties) muscular, 118 (71) vascular, 29 (18) neural, 10 (7) visceral and 1 bone anomaly; by region, there were 50 in the head and trunk, 56 in the upper limbs, and 52 in the lower limbs. The other 71 anomalies were vascular ones confined to the viscera (61) and visceral (10). A maximum of 26 anomalies, including 10 muscular, 14 vascular and 2 neural anomalies, were ascertained to exist coincidentally in a single male. Among vascular anomalies, the visceral ones (61) were dominant. In all structures, 75% of the varieties of anomalies were single occurrences. In the text, the multiple occurrence of anomalies in an individual and their relationships are discussed.

Aged↗