Oral lichen planus: study of 21 cases

BACKGROUND:

Lichen planus is considered to be the most common dermatological disease involving the oral mucosa.

OBJECTIVE:

To investigate the profile, clinical features, and the presence of dysplasia and candidiasis in patients with oral lichen planus.

METHODS:

A total of 21 patients were selected from 258 patients at risk for oral cancer development.

RESULTS:

Most of the patients were white (76,2%), female (66,6%), with mean age of 58.8 years. Eight were smokers and seven were alcohol consumers. The buccal mucosa was the most affected site, followed by the tongue and the gingiva. The reticular pattern was the most common appearance. Histopathology depicted dysplasia in nine cases and cytopathology was positive for Candida in eight cases in the first appointment.

CONCLUSION:

Our data are similar to the literature. Cytopathology was important for the diagnosis of candidiasis. Although the presence of dysplasia was verified, further studies are necessary to clarify the importance of this finding.     

Lung Radiofrequency Ablation: In Vivo Experimental Study with Low-Perfusion-Rate Multitined Electrodes

The purpose of this study was to investigate the feasibility and safety of lung radiofrequency (RF) ablation by using low-perfusion-rate, expandable, multitined electrodes in an in vivo animal model. Ten New Zealand White rabbits underwent RF ablation using low-perfusion-rate, expandable, multitined electrodes (Starburst Talon; RITA Medical Systems, Mountain View, CA) and a 200-W RF generator. The electrode was positioned under fluoroscopy guidance and a single percutaneous RF ablation was performed. Saline perfusate was doped with nonionic iodinated contrast agent to render it visible on computed tomography (CT). The pump infused the saline doped with contrast agent into the lateral tines at a rate of 0.1ml/min. The planned ablation was of 3 min, with the hooks deployed to 2 cm at a target temperature of 105°C. An immediate posttreatment CT scan documented the distribution of the doped saline and the presence of immediate complications. The animals were monitored for delayed complications and sacrificed within 72 h (n = 4), 2 weeks (n = 3), or 4 weeks (n = 3). Assessment of ablation zone and adjacent structures was done at autopsy. Major complications consisted of pneumothorax requiring drainage (n = 2) and skin burn (n = 1). Immediately after the procedure the area of ablation was depicted at CT as a round, well-demarcated area, homogeneously opacified by iodinated contrast medium (mean size, 2.3 ± 0.8 cm). The presence of a sharply demarcated area of coagulation necrosis (mean size, 2.1 ± 0.4 cm) without severe damage to adjacent structures was confirmed at autopsy. In one case, euthanized at 4 weeks, in whom pneumothorax and pleural effusion were depicted, pleural fibrinous adhesions were demonstrated at autopsy. In conclusion, lung RF ablation performed in an in vivo animal model using low-perfusion-rate, expandable, multitined electrodes is feasible and safe. No severe damage to adjacent structures was demonstrated.     

Granulocyte- and monocyte-platelet adhesion index in coronary and peripheral blood after extracorporeal circulation and reperfusion

BACKGROUND: Neutrophil-granulocyte and mononuclear-cell functional changes occur during cardiopulmonary bypass and cardiovascular surgery. In particular, leukocyte-platelet interaction, leading to generation of heterotypic coaggregates, represents an amplification mechanism of the local inflammatory response and tissue damage. METHODS: Samples of 20 patients were drawn from venous coronary sinus before cardioplegic arrest and immediately after reperfusion, as well as from peripheral blood at 5 and 24 h postoperatively. The granulocyte and monocyte surface expression of CD162, CD15s, CD18, and CD11b were quantified by flow cytometry at the different times. Parallel variations of circulating leukocyte-platelet conjugates (percentages) and a derived (cell number-normalized) leukocyte-platelet adhesion index were measured using a combination of antibodies against CD45, CD14, and CD41a. The evaluation of platelet functional state was carried out using antibodies against CD62P (P-selectin) and PAC-1. RESULTS: Monocyte and granulocyte cell number increased markedly in coronary blood at reperfusion and in peripheral blood postoperatively when compared with measurements done before cardioplegia. A very different course characterized the changes of the leukocyte-platelet adhesion index with respect to the variations of circulating leukocyte-platelet coaggregates (percentages). Leukocyte molecules expression showed no significant variations for CD15s on both the leukocyte subsets, while a significant up-modulation for CD162 was observed on monocytes at 24 h after extracorporeal circulation (P = 0.0002), and for CD11b on granulocytes at 5 h postoperatively (P = 0.033). A loss of CD162 expression was observed in coronary blood at reperfusion (P = 0.0038) on granulocytes, associated to a down-modulation of CD18 (P = 0.0033) and CD11b (P = 0.0184) in peripheral blood at 24 h postoperatively. No significant up-regulation of platelet activatory molecules expression was found at coronary reperfusion, as well as postoperatively in the peripheral blood, when compared with the before-cardioplegia derived data. CONCLUSIONS: The over time variations of a normalized leukocyte-platelet adhesion index seem to reflect the cumulative leukocyte-platelet functional interaction more accurately than the parallel measurements of cellular conjugates. The absence of platelet activation suggests that the leukocyte membrane modifications play a main role in controlling the formation and stability of heterotypic leukocyte-platelet coaggregates after cardiac surgery with extracorporeal circulation.     

Enhancement of SCE frequency by alpha-naphthoflavone in cultured lymphocytes in relation to environmental factors

One hundred and nine healthy subjects living in an urban area of Tuscany were monitored using sister chromatid exchange (SCE) analysis on lymphocytes cultured in standard or alpha-naphthoflavone (ANF)-supplemented medium in order to collect the most complete data possible for those constitutional and environmental factors with which genotoxic risk can be associated. ANF genotoxicity depends on its metabolic activation by cellular P-450 monooxygenase systems whose activity can be modulated by exposure to carcinogenic but nongenotoxic xenobiotics. Lymphocytes grown in standard conditions showed a significant increase of SCE frequency associated with smoking habits and age. Although the addition of ANF caused an upward shift of SCE frequency in all subjects, smokers, coffee drinkers, and blue-collar workers showed a significantly higher SCE level; this suggests that potential risk factors rising from a modified cell metabolism are present in these categories. These results indicate that in vitro ANF treatment of lymphocytes could be a useful tool in the detection of environmental exposure to those classes of chemicals involved in metabolic activation of promutagens. © 1995 Wiley-Liss, Inc.     

Modulating factors of individual sensitivity to diepoxybutane: chromosome aberrations induced in vitro in human lymphocytes

Peripheral blood lymphocytes from a sample of 62 randomly selecteddonors were analysed for spontaneous and diepoxybutane (DEB)-inducedchromosomal aberrations (CA). These individuals were part ofa larger sample of 122 subjects whose DEB responsiveness wasevaluated by means of sister chromatid exchange (SCE) analysis.Confounding factors (such as smoking, wine and coffee consumption,occupation and haematological factors) were analysed for theireffect on individual DEB-responsiveness, but no statisticallysignificant associations were observed. Interestingly, a bimodaldistribution of aberrant cell frequencies was clearly detectable,showing the existence of DEB-sensitive subjects belonging tothe second mode (CA frequencies >19%). When responsivenessevaluated by means of CA induction was compared with SCE responsiveness,it was noted that all SCE-inducible subjects (>110.9 SCEs/cell)belonged to the second mode of CA frequency distribution. Onthe other hand, highly CA inducible individuals did not necessarilyshow a higher SCE-response, although their DEB-induced SCE frequencieswere above average (92 SCEs/cell). DEB-induced CA frequencycorrelated with baseline levels, indicating that DEB-sensitiveindividuals also showed higher spontaneous chromosome damage(3.6 versus DEB-resistant 2%, P < 0.05). Finally, when simpleand multiple regression analyses were carried out, DEB-sensitivityappeared negatively related to haematic concentrations of proteinsand uric acid (intercept 0.131 ± 0.011, slope –0.029± 0.0116, r = –0.39; P < 0.01), probably dueto its antioxidant activity. This finding confirmed previousobservations on the scavenger activity of plasma factors onDEB mutagenicity. ¹To whom correspondence should be addressed     

Caffeine post-treatment causes a shift in the chromosome aberration types induced by mitomycin C, suggesting a caffeinesensitive mechanism of DNA repair in G2

Human lymphocytes were exposed in G₁ to mitomycin C (2.5 µMfor 2 h) and harvested at 3-h intervals from 48 to 84 h afterstimulation. All cultures were also post-treated in G₂ withcaffeine (2mM). Different types of chromosomal aberrations werescored in the first division metaphases. Caffeine increasesall chromosome aberration types by promoting a premature mitosisof damaged cells. However, when the frequency of damaged cellsis not affected by the caffeine post-treatment, a reductionof the frequency of the exchange-type aberrations was shown.The possibility that caffeine interferes with some mechanismof G₂ repair is discussed. ¹To whom correspondence should be addressed     

Functional and molecular defects of pancreatic islets in human type 2 diabetes

To shed further light on the primary alterations of insulin secretion in type 2 diabetes and the possible mechanisms involved, we studied several functional and molecular properties of islets isolated from the pancreata of 13 type 2 diabetic and 13 matched nondiabetic cadaveric organ donors. Glucose-stimulated insulin secretion from type 2 diabetic islets was significantly lower than from control islets, whereas arginine- and glibenclamide-stimulated insulin release was less markedly affected. The defects were accompanied by reduced mRNA expression of GLUT1 and -2 and glucokinase and by diminished glucose oxidation. In addition, AMP-activated protein kinase activation was reduced. Furthermore, the expression of insulin was decreased, and that of pancreatic duodenal homeobox-1 (PDX-1) and forkhead box O1 (Foxo-1) was increased. Nitrotyrosine and 8-hydroxy-2'-deoxyguanosine concentrations, markers of oxidative stress, were significantly higher in type 2 diabetic than control islets, and they were correlated with the degree of glucose-stimulated insulin release impairment. Accordingly, 24-h exposure to glutathione significantly improved glucose-stimulated insulin release and decreased nitrotyrosine concentration, with partial recovery of insulin mRNA expression. These results provide direct evidence that the defects of insulin secretion in type 2 diabetic islets are associated with multiple islet cell alterations. Most importantly, the current study shows that the functional impairment of type 2 diabetic islets can be, at least in part, reversible. In this regard, it is suggested that reducing islet cell oxidative stress is a potential target of human type 2 diabetes therapy.