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91.
Khanna M Fortier-Riberdy G Dinehart SM Smoller B 《Journal of the American Academy of Dermatology》2003,48(5):721-726
BACKGROUND: There are numerous histopathologic features related to prognosis in cutaneous squamous cell carcinoma (CSCC). We hypothesize that there is no uniform approach toward the reporting of these features. This may be related to differing opinions on their prognostic use. METHODS: A written survey concerning the microscopic evaluation of CSCC was sent to 120 dermatopathologists in the United States and Canada. Respondents were asked whether they comment on specific microscopic features of CSCC, and whether they believe that each specific feature can predict prognosis. RESULTS: The response rate was 78%. Histologic type, and the presence of perineural or vascular/lymphatic invasion, is reported by most dermatopathologists (90%, 96%, and 95%, respectively). These features are also thought to predict prognosis by the majority of respondents. Only 54% report histologic grade, and 49% think grade predicts prognosis. Depth is reported anatomically by 63%, but by only 8% in actual millimeters of invasion. However, 55% think tumor depth predicts prognosis. A total of 43% report the presence of an associated actinic keratosis, although very few (16%) think it predicts prognosis. Very few comment on the presence of inflammation. CONCLUSIONS: Histopathologic reporting of CSCC is not uniform among dermatopathologists. Also, there appears to be differing opinions on the use of certain histopathologic features for predicting prognosis. 相似文献
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Not only training but also exposure to chlorinated compounds generates a response to oxidative stimuli in swimmers 总被引:4,自引:0,他引:4
Varraso R Massin N Hery M Fradier-Dusch M Michaely JP Fournier M Hubert G Biette P Rieger B Berthelin A Hecht G Nadif R 《Toxicology and industrial health》2002,18(6):269-278
Relations between exposure to chlorinated compounds and biological markers of response to oxidative stimuli were investigated in swimmers, taking into account the effect of training. Twenty-two male swimmers aged 15-25 years were surveyed twice. Prevalence of irritant symptoms and asthma and number of hours of training were reported. Exposure to nitrogen trichloride (NCl3) and blood response to oxidative stimuli [catalase, superoxide dismutase (Cu2+/Zn2+ SOD), glutathione peroxidase (GSH-Px) activities and ceruloplasmin, ferritin and total antioxidant concentrations] were measured. Univariate analyses were completed by multivariate analyses. High prevalences of irritant symptoms and asthma were found. Multivariate analysis confirmed the results of the univariate analyses and showed that Cu2+/Zn2+ SOD activity was increased by exposure and by training (P = 0.01, P = 0.0001, respectively). Erythrocyte GSH-Px was decreased, whereas plasma GSH-Px was increased by exposure (P = 0.002, P = 0.002). No other association was found. Higher irritant symptoms and increases in the activities of erythrocyte Cu2+/Zn2+ SOD and of plasma GSH-Px with exposure support the hypothesis that the production of reactive oxygen species is not only related to training but also to exposure to chlorinated compounds. Other athletes tend to have respiratory problems such as asthma, but the exposure to chlorinated compounds may increase the respiratory disease among swimmers. 相似文献
95.
Growth phase-dependent expression of ICAD-L/DFF45 modulates the pattern of apoptosis in human colonic cancer cells 总被引:10,自引:0,他引:10
Charrier L Jarry A Toquet C Bou-Hanna C Chedorge M Denis M Vallette G Laboisse CL 《Cancer research》2002,62(7):2169-2174
The inhibitor of caspase-3-activated DNase (ICAD) is a caspase-3 substrate that controls nuclear apoptosis. ICAD has two isoforms: a functional isoform of M(r) 45,000, ICAD-L/DNA fragmentation factor (DFF) 45; and a M(r) 35,000 isoform, ICAD-S/DFF35. ICAD-deficient murine cells display resistance to apoptotic stimuli and absence of typical nuclear changes of apoptosis. Our aim was to: (a) characterize the ICAD expression in several human colonic cancer cell lines compared with human normal colonocytes; and (b) correlate the phenotypic features of apoptosis to the level of ICAD expression. ICAD expression was assessed by immunoblot analysis. Early markers of apoptosis of cultured cells included lactate dehydrogenase retention in dying cells, cytokeratin 18 cleavage, and caspase-3 activation. Nuclear markers of apoptosis were assessed by Hoechst staining of nuclei, electron microscopy, and DNA electrophoresis. Inhibition of caspases was performed using a broad-spectrum caspase inhibitor, z-Val-Ala-Asp-fluoromethyl ketone. ICAD expression was restricted to the functional ICAD-L/DFF45 isoform in colonic cancer cells as well as in human normal colonocytes. In a clonal derivative of HT29 cells (HT29-Cl.16E cells), ICAD expression was found to be down-regulated during the exponential phase of growth, and the cell death triggered by IFN-gamma, anti-Fas antibody plus Adriamycin was characterized by the expression of early markers of apoptosis, whereas the key nuclear features of apoptosis were absent. In contrast, exposure of confluent cells to this treatment led to a typical apoptotic nuclear fragmentation. Both forms of apoptosis, in exponentially growing and confluent cells, were sensitive to the broad spectrum inhibitor of caspases, z-Val-Ala-Asp-fluoromethyl ketone. Our findings support the concept that the expression of ICAD is essential to the execution of full-blown apoptosis in colonic cancer cells. Altogether, our results point to ICAD as a potential target for restoring a normal apoptotic signal transduction pathway in colonic cancer cells. 相似文献
96.
Petit L Claudine Piérard-Franchimont Saint Léger D Loussouarn G Piérard GE 《European journal of dermatology : EJD》2002,12(6):565-568
Based on the clinical presentation of some skin pigmentation disorders it is thought that a bicompartmental functional system exists in the epidermal melanocyte population. It corresponds to the perifollicular and interfollicular compartments, respectively. The present study was undertaken looking for the presence of such a system on scalp unaffected by pigmentary disorders. The scalps of 100 men with incipient to severe androgenic alopecia were examined using a videocamera equipped with an internal ultraviolet light-emitting unit. The face, trunk and limbs were similarly examined in 45 of these adults and in 13 children of both sexes. In 92 men, a subclinical hypermelanosis was found as a speckled pattern centered on every single follicle. With increasing baldness severity, another epidermal hyperpigmentation pattern involving the interfollicular area was superimposed to the perifollicular pattern. These stereotyped patterns of subclinical melanoderma were also disclosed on the face of adults, but not in children. In addition, the spotty perifollicular pattern was discrete or not apparent on the other parts of the body. It is concluded that the perifollicular subclinical melanotic pattern is a regional characteristic of cephalic skin, perhaps related to the local production of melanocortins, particularly alpha-MSH by the pilosebaceous unit. 相似文献
97.
Manrique A Tapon E Derumeaux G Cribier A Véra P Dacher JN 《Journal of computer assisted tomography》2002,26(5):676-680
PURPOSE: The aim of this study was to evaluate whether Fourier analysis of cine-MR could detect wall motion abnormalities in patients with myocardial infarction. METHODS: Ten patients with anterior myocardial infarction (seven men and three women; mean age, 58 +/- 16 years) were compared with six control subjects (four men and two women; mean age, 49 +/- 24 years). Gradient echo cardiac cine-MR slices were transformed using a commercially available Fourier algorithm to obtain phase angles of endocardial segments. Mean phase angle and phase dispersion (i.e., SD around the mean) were calculated. Segmental wall motion was evaluated using a 16-segment model and correlated to Fourier phase analysis. RESULTS: Mean phase angle and phase dispersion were increased in patients compared with control subjects (respectively, 191 degrees +/- 23 degrees vs. 161 degrees +/- 25 degrees, P < 0.0001 and 21 degrees +/- 10 degrees vs. 11 degrees +/- 8 degrees, P = 0.0007). Analysis of variance showed a significant increased dispersion on basal slices (P = 0.002) mostly due to flow-void and entry slice phenomenon. CONCLUSIONS: Fourier phase analysis of cardiac cine-MR is feasible and allows the evaluation of ventricular asynergy on the basis of endocardial wall motion. 相似文献
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Ultrasound-guided infraclavicular versus supraclavicular block 总被引:3,自引:0,他引:3
Arcand G Williams SR Chouinard P Boudreault D Harris P Ruel M Girard F 《Anesthesia and analgesia》2005,101(3):886-90, table of contents
In this prospective study we compared ultrasound-guided (USG) infraclavicular and supraclavicular blocks for performance time and quality of block. We hypothesized that the infraclavicular approach would result in shorter performance times with a quality of block similar to that of the supraclavicular approach. Eighty patients were randomized into two equal groups: Group I (infraclavicular) and Group S (supraclavicular). All blocks were performed using ultrasound visualization with a 7.5-MHz linear probe and neurostimulation. The anesthetic mixture consisted of 0.5 mL/kg of bupivacaine 0.5% and lidocaine hydrocarbonate 2% (1:3 vol.) with epinephrine 1:200,000. Sensory block, motor block, and supplementation rates were evaluated for the musculocutaneous, median, radial, and ulnar nerves. Surgical anesthesia without supplementation was achieved in 80% of patients in group I compared with 87% in Group S (P = 0.39). Supplementation rates were significantly different only for the radial territory: 18% in Group I versus 0% in group S (P = 0.006). Block performance times were not different between groups (4.0 min in Group I versus 4.65 min in Group S; P = 0.43). Technique-related pain scores were not different between groups (I: 2.0; S: 2.0; P = 1.00). We conclude that USG infraclavicular block is at least as rapidly executed as USG supraclavicular block and produces a similar degree of surgical anesthesia without supplementation. 相似文献