OBJECTIVETo investigate the correlation between the expression of key proto-oncogenes playing major roles in tumorigenic process and abnormal sarring.

METHODSImmunohistochemical technique was performed to detect the expressions of c-myc, c-fos and ras p21 proteins on hypertrophic scars, keloids and normal skin. Image analysis was used to compare their quantitative difference of expression.

RESULTSC-myc and c-fos expressions on the nucleus of fibroblasts of hypertrophic and keloid scars were significantly higher than normal skin controls, and there was no difference between the two lesions. Ras p21 expression was not detected on the fibroblasts of hypertrophic and keloid scars.

CONCLUSION1. c-myc and c-fos oncogenes are activated on hypertrophic and keloid scars, which may contribute to proliferation and differentiation of fibroblasts, synthesis and degradation of collagen and regulation of cytokines and induce abnormal scarring, the mechanisms of their effects remain to be further studied. 2. Ras gene may not mutate or its mutations may not play a major role in the process of abnormal scarring. 3. Only part of proto-oncogenes moderately expressed on abnormal scars. The expression of multiple oncogenes does not coexist in abnormal scars may be the cause of their less chances to induce malignant transformation.

Cicatrix, Hypertrophic ; metabolism ; Humans ; Immunohistochemistry ; Proto-Oncogene Proteins c-fos ; analysis ; Proto-Oncogene Proteins c-myc ; analysis ; Proto-Oncogene Proteins p21(ras) ; analysis ; Proto-Oncogenes

BACKGROUNDNicotine may improve schizophrenia patient's cognitive deficit symptoms. This study was to explore the chronic effects of smoking on prepulse inhibition of the startle reflex (PPI) and P50 in the patients with first-episode schizophrenia (FES).

METHODSThe event-related potentials (ERP) recording and analysis instrument made by Brain Products, Germany, was used to detect PPI and P50 in 49 male FES patients (FES group, n = 21 for smokers and n = 28 for non-smokers) and 43 normal male controls (control group, n = 19 for smokers and n = 24 for non-smokers).

RESULTSCompared with normal controls, the FES group had prolonged PPI latency when elicited by single stronger stimulus (P < 0.05); the FES group had prolonged PPI latency and increased PPI amplitude (P < 0.05, 0.01) when elicited by weak and strong stimuli. The FES group had lower PPI inhibition rate than normal controls (P < 0.05). Compared with normal controls, the FES group had increased P50-S2 amplitude and increased amplitude ratio S2/S1 (both P <0.05). In the control group, the smokers had a tendency of increase in P50-S2 amplitude (P > 0.05) and shorter P50-S2 latency (P < 0.05) than the non-smokers. The smokers had higher PPI amplitude than the non-smokers (P < 0.05). In the FES group, the smokers had higher P50-S1 amplitude, shorter P50-S2 latency, and higher amplitude ratio S2/S1 than the non-smokers (P < 0.05, 0.01). The smokers had higher PPI amplitude than the non-smokers (P < 0.05).

CONCLUSIONSThere is obvious PPI and P50 deficits in schizophrenic patients. However, these deficits are relatively preserved in the smokers compared with the non-smokers, which suggests that long-term smoking might partially improve the sensory gating in schizophrenic patients. Whether this conclusion can be deduced to female patients requires further follow-ups.

Adult ; Case-Control Studies ; Evoked Potentials ; drug effects ; physiology ; Humans ; Male ; Reflex, Startle ; physiology ; Schizophrenia ; physiopathology ; Smoking ; adverse effects ; Young Adult