Road safety education: What works?

OBJECTIVES: The objectives of the paper are: METHOD: Seminal papers, collaborative reports from traffic safety research institutes and books from experts have been used as materials. Very diverse fields of application are presented such as: the importance of emotional experience in interaction with traffic experiences; the efficiency of e-learning; the efficiency of simulators to improve hazard perception skills and calibration of one's driving competencies; the efficiency of social norms marketing at changing behaviors by correcting normative misperceptions; the usefulness of parents-based interventions to improve parental supervision; and finally the importance of multi-components programs due to their synergies. CONCLUSIONS: Scientific evidence collected in this paper shows that RSE may have some positive effects if good practices are adopted, if it is part of a lifelong learning process and if transmits not only knowledge but also "life-skills" (or psycho-social competences). IMPLICATIONS: for practice From each example, we will see the implications of the results for the implementation of RSE.

Diagnosis and prediction of recurrence and progression in superficial bladder cancers with DNA image cytometry and urinary cytology.

OBJECTIVE: To investigate the roles of urinary cytology and image cytometric analysis of nuclear DNA ploidy pattern in the diagnosis and prediction of recurrence and/or progression of superficial bladder cancers. PATIENTS AND METHODS: Aliquots of catheterized urine from 92 patients with primary (23) or previous (69) superficial bladder cancers were assessed using urine cytology and image-analysis cytometry independently. RESULTS: Of the 23 primary superficial transitional cell carcinomas (TCCs), 11 (48%) were detected by urinary cytology while 12 (52%) were detected by image-analysis cytometry (P>0.05) and 13 (57%) were revealed by combined cytology and cytometry. Of 42 recurrent superficial TCCs, 29 (69%) were detected by urinary cytology, whilst 19 (45%) were diagnosed by cytometry (P<0.05) and 29 (69%) by combined cytology and cytometry. The degree of ploidy in relation to pathological stage and/or grade showed an increasing frequency of aneuploid pattern in more invasive and undifferentiated tumours, but with no statistical significance (P>0.05). The positivity of DNA image cytometry had no significant association (P>0.05) with tumour recurrence and/or progression. CONCLUSIONS: DNA image cytometry can provide a limited but not significant advantage over urinary cytology in the detection of primary superficial TCCs, but it does not seem to be indicated for the prediction of tumour recurrence and/or progression.

Diagnosis and prediction of recurrence and progression in superficial bladder cancers with DNA image cytometry and urinary cytology

OBJECTIVE: To investigate the roles of urinary cytology and image cytometric analysis of nuclear DNA ploidy pattern in the diagnosis and prediction of recurrence and/or progression of superficial bladder cancers. PATIENTS AND METHODS: Aliquots of catheterized urine from 92 patients with primary (23) or previous (69) superficial bladder cancers were assessed using urine cytology and image-analysis cytometry independently. RESULTS: Of the 23 primary superficial transitional cell carcinomas (TCCs), 11 (48%) were detected by urinary cytology while 12 (52%) were detected by image-analysis cytometry (P > 0.05) and 13 (57%) were revealed by combined cytology and cytometry. Of 42 recurrent superficial TCCs, 29 (69%) were detected by urinary cytology, whilst 19 (45%) were diagnosed by cytometry (P < 0.05) and 29 (69%) by combined cytology and cytometry. The degree of ploidy in relation to pathological stage and/or grade showed an increasing frequency of aneuploid pattern in more invasive and undifferentiated tumours, but with no statistical significance (P > 0.05). The positivity of DNA image cytometry had no significant association (P > 0.05) with tumour recurrence and/or progression. CONCLUSIONS: DNA image cytometry can provide a limited but not significant advantage over urinary cytology in the detection of primary superficial TCCs, but it does not seem to be indicated for the prediction of tumour recurrence and/or progression.

Heterogeneity of DNA distribution in diploid cells: a new predictive discriminant factor for solid tumour behaviour.

Spatial nuclear DNA heterogeneity distribution of Feulgen-stained DNA diploid cells was studied by image cytometry in voided urine of 119 patients without bladder tumour (n = 20) and with initial (n = 23) or previous (n = 76) diagnosed bladder tumour. For each patient, repetitive DNA measurements were performed during 1-4 years of follow up. Only cells of diploid DNA histograms and diploid subpopulations of aneuploid DNA histograms were used for analysis. DNA heterogeneity distribution of these diploid cells was quantified by statistical parameters of each nuclear optical density distribution. Discriminant analysis was performed on three groups of DNA histograms. Group A (n = 44): aneuploid DNA histograms of patients with bladder tumour. Group D (n = 55): 38 diploid DNA histograms of the 20 patients without bladder tumour (subgroup D1) and 17 diploid DNA histograms of patients with a non-recurrent bladder tumour (subgroup D2). Group R (n = 27): diploid DNA histograms of patients with bladder tumour recurrence. No statistically significant discriminant function was found to separate D1 and D2. However, the first canonical discriminant function C1 differentiated diploid cells of diploid DNA histograms (group D and group R) from diploid cell subpopulations of aneuploid DNA histograms (group A). Mean C1 values were 1.06, 0.84 and -1.45 for groups R, D and A, respectively. The second canonical discriminant function C2 differentiated diploid DNA histograms of patients with bladder tumour recurrence (group R) from diploid DNA histograms of patients without bladder tumour or without bladder tumour recurrence (group D). Mean C2 values were 1.78 and -0.76 for groups R and D, respectively. In 95% confidence limit, the rate of rediscrimination using the two first canonical discriminant functions C1 and C2 were 86.4, 74.5 and 74.1% for groups A, D and R, respectively. Percent of "grouped" cases correctly classified was 78.6%. Thus spatial DNA heterogeneity distribution of diploid cells seems to quantitate probable genetic instability as a function of clinical evolution such as tumour recurrence, and suggests the possible presence of aneuploid stemlines in a heterogeneous tumour, even if a diploid DNA histogram is observed in a single sample. From standardized C1 and C2 canonical discriminant function coefficients, a DNA heterogeneity index (2c-HI) is proposed to characterize diploid cells providing a descriptive and predictive discriminant factor for solid tumour behaviour.

Comparative effects of 17 beta-estradiol, progestin R5020, tamoxifen and RU38486 on lactate dehydrogenase activity in MCF-7 human breast cancer cells.

The effects of 17 beta-estradiol (estradiol), synthetic progestin R5020 and their antagonists, tamoxifen (Tam) and synthetic RU38486 on lactate dehydrogenase (LDH) activity in MCF-7 human breast cancer cells during the growth period were studied. A specially developed quantitative cytochemical assay was used; LDH activity is expressed per cell, and is thus independent of the positive and negative growth effects of the hormones and antagonists. Estradiol and R5020 stimulated LDH activity after similar exposures (6-48 h) and the stimuli were concentration dependent over the range 10(-7) M to 10(-10) M. As for the antagonists, RU38486 stimulated LDH activity in much the same way as estradiol and R5020; Tam alone, on the other hand, does not stimulate LDH, but when added to estradiol, Tam inhibits estradiol mediated LDH activation. When present at half-stimulant concentration, estradiol + R5020 and estradiol + RU38486 exhibit additive effects on LDH activity. Thus LDH appears to be an interesting tool for the study of hormone and antagonist effects in MCF-7 breast cancer cells.

[Contribution of quantitative cytology and ploidy in the diagnosis and monitoring of tumors of the bladder. Study of 52 cases using the Samba analyser]. / Apport de la cytologie quantitative et de la ploïdie dans le diagnostic et la surveillance des tumeurs de la vessie. Etude de 52 cas par l'analyseur Samba.

Image processors and present specific software applications have now placed scanning microcytometry in the ranks of other conventional technics for routine laboratory examinations, particularly for urinary cytology and DNA measurements (ploidy). Conventional urinary sediment smears of 52 patients with bladder tumor were digitized, processed and statistically analyzed by the image analyzer, Samba. They were automatically classified and ploidy measurements were made and compared with 6 conventional cytological diagnostics for each smear. The Samba program assigns the cell images to two classes, negative and positive. 100% of the cells were correctly classed with respect to the cytologist's diagnostics. Within the positive class the degree of malignancy established by the program was the same as the cytologist's classifications. For smears of class III, the comparison of the diagnostics of the cytologists for each patient permitted the validation of the differential classification, negative-positive, made using quantitative cytology. The interpretation of the two DNA histogram parameters, the degree of ploidy and the proliferation index, provided an excellent prognosis of which patients would show tumoral recrudescence, as verified by follow ups.

Kinetic analysis of lactate dehydrogenase in cultured chondrocytes by quantitative cytochemistry.

Kinetic analysis of lactate dehydrogenase activity in intact cultured chondrocytes was performed in situ by coupling cell culture and microcytophotometry. Cells were cultured on glass microscope slides divided into eight chambers and studied during the growth cycle in monolayer areas. Lactate dehydrogenase activity was assayed by the reduction of neotetrazolium in the presence of phenazine methosulfate. Quantification of formazan deposits within the cells was performed by scanning and integrating microdensitometry at the isosbestic wavelength of 585 nm. Results indicate the following (a) A kinetic characterization was possible: apparent constants, Km and Ks of this two-substrate enzyme were graphically determined Ks = 1.05 +/- 0.08 and 0.56 +/- 0.05 mM for lactate and NAD respectively and Km = 0.64 +/- 0.03 and 0.37 +/- 0.02 mM for lactate and NAD respectively. (b) Inhibition by lactate concentrations above 10 mM and pyruvate concentration of 1 mM, is in agreement with the well known high anaerobic glycolytic metabolism of chondrocytes. This was confirmed by electrophoresis on cellulose acetate which demonstrated a M3-H isoenzyme form in cultured chick chondrocytes. This study shows that microcytophotometric analysis of lactate dehydrogenase in cultured chondrocytes may be an interesting alternative to mass culture cells followed by classical biochemical studies.

In situ biochemical studies of intestinal alkaline phosphatase in normal and phosphate-depleted rats by microdensitometry.

A quantitative microdensitometric study has been designed to characterize in situ intestinal brush border-bound alkaline phosphatase of rat duodenal villosities. Intestinal slices were incubated with beta-glycerophosphate as substrate. Free phosphate liberated was precipitated in presence of a lead reagent as lead sulfide. The precipitate was quantified in situ by scanning and integrating microdensitometry. Kinetic parameters of the reaction were determined at 37 degrees C, pH 8.8, in the middle part of the villosities. Apparent Michaelis constant (Km) for beta-glycerophosphate was found to be 8.16 +/- 0.56 mM (mean +/- S.E.). Maximal enzyme activation was obtained at pH 8.5. Maximal inhibition of enzyme activity was observed in the presence of L-phenylalanine (30 mM) or theophylline (5 mM). Along the villosity axis, enzyme activity rose from the crypt up to the midportion of the villosity and finally decreased at the tip region. In phosphate-depleted rats, enzyme activity was increased in all portions of the villosity, with conservation of the same activity gradient. In this situation, kinetic analysis showed a marked decrease of Km, i.e. 4.56 +/- 0.39 mM (mean +/- S.E.) as compared to normal rats.

Noninvasive experimental determination of the individual kidney filtration fraction by means of a dual-tracer technique.

A noninvasive method for measurement of the individual kidney filtration fraction (FF) is presented, based on an analysis of the early rise of the kidneys' time-activity curves obtained after simultaneous injection of tubular [131I] ortho-iodohippurate and glomerular (Tc-99m DTPA) tracers. The analysis is based on the assumption that an insignificant amount of tracer leaves the kidney during the first few moments following injection. Therefore the kidney activity during this period is directly proportional to the integral of the blood (heart) activity. The dual-tracer technique allows the direct calculation of the ratio of glomerular to tubular clearances, i.e., the FF. In vivo studies were performed on 12 dogs, including normals as well as others with acute ureteral ligation or Benemid-induced tubular blockade. The calculated FF correlated well with the FF obtained from single-shot clearances performed simultaneously. We conclude that the FF can be calculated directly for each kidney, noninvasively, from the early part of the tubular and glomerular time-activity curves by noninvasive external detection.

Liquid scintillation counting for measurement of tritiated uptake in lymphocyte transformation in vitro: a new direct-suspension procedure.

Liquid scintillation counting of trichloracetic acid extracts of [3H] TdR-labelled lymphocytes has been studied by a direct suspension method without previous solubilization. In this new method, mixing of the labelled powder in water suspension with Scintillator Emulsifying Mixture (SEM) results in a firm gel whose mechanical properties provide an heterogeneous sample ready for counting. Counting efficiency and stability of such samples are related to the amount of labelled cells. Comparative studies with standard hyamine procedure have shown that this simple and rapid method gives reliable results.

Hepatic homing of labelled lymphocytes in man.

The homing of human lymphocytes has been studied in man by means of chromium labelling and external organ counting. The method was applied to the study of lymphocyte alteration induced by antilymphocyte globulin (A.L.G.). At non-cytotoxic concentrations A.L.G. has an opsonizing effect on lymphocytes, increasing selectively their homing to the liver. No correlation could be defined between in-vitro cytotoxicity or rosette-inhibiting activity and hepatic fixation. These results suggest that A.L.G. may act by promoting lymphocyte trapping by the reticuloendothelial cells.