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Renate Hochscheid Sven Heinrichs Stephan Kranz Holger Garn Bernd Müller 《Free radical research》2013,47(7):759-767
The lung is protected against oxidative stress by a variety of antioxidants and type II pneumocytes seem to play an important role in antioxidant defense. Previous studies have shown that inhalation of NO2 results in acute and chronic lung injury. How the expression and enzyme activity of antioxidant enzymes are influenced in type II cells of different inflammatory stages has yet not been studied. To elucidate this question, we exposed rats to 10 ppm NO2 for 3 or 20 days to induce acute or chronic lung injury. From these and air-breathing rats, type II pneumocytes were isolated. The mRNA expression and protein content of CuZnSOD and MnSOD as well as total SOD-specific enzyme activity were determined. For the acute lung injury (3 d NO2), the expression of CuZnSOD mRNA was significantly increased, while MnSOD expression was significantly reduced after 3 days of NO 2 exposure. For the chronic lung injury (20 d NO2), CuZnSOD expression was still enhanced, while MnSOD expression was comparable to control. In parallel to CuZnSOD mRNA expression, the protein amount was significantly increased in acute and chronic lung injury however MnSOD protein content exhibited no intergroup differences. Total SOD enzyme activity showed a significant decrease after 3 days of NO2 exposure and was similar to control after 20 days. We conclude that during acute and chronic lung injury in type II pneumocytes expression and protein synthesis of CuZnSOD and MnSOD are regulated differently. 相似文献
95.
Safae Mansouri Luis A. Glaria Naim Asmae Luis F. Flores 《Reports of Practical Oncology and Radiotherapy》2013,18(3):182-188
Metastatic carcinoma to the vulva is rare, where the incidence is believed to be between 5% and 8%.However, malignant tumors have been described in 3–11% of systemic scleroderma (SSc) cases.We report the case of one patient, a 66-year-old postmenopausal woman, whose medical history was marked with rheumatic vascular disease (systemic scleroderma) since 1993 without muscular, renal, cardiac lesions or HTA (arterial hypertension) and without tobacco history.The woman presented with a new vulvar mass of the right labia in December 2011 that had progressively enlarged in size.CT scan of the abdominopelvic region demonstrated a lobular mass of the right labia with central necrosis, 7 cm on the wide axis, and the rectum and the vaginal wall were normal. No inguinal or iliac lymphadenopathy was noted.An outpatient excisional biopsy revealed a poorly differentiated malignant tumor suggestive of carcinoma.IHC: CK7+/CK20−, estrogen receptors−, AE 1 AE 3+, vimentine+, S100−, Desmina−, CD34−, KI 67: 20%.The thoracic scan revealed a large mass of 4 cm × 3 cm in the right lung base with right paratracheal lymphadenopathy 3 cm × 2 cm.A bronchoscopy revealed discrete stenosis of the mediastinal portion of the right bronchial tree.The bronchial biopsy also revealed poorly differentiated lung carcinoma, non-small cell, which was identical with the vulvar tumor.
Conclusion
The presence of the single lung lesion with only one lymphadenopathy paratracheal with pathological and immunohistochemical (IHC) profile similar to the vulvar lesion, and a particular IHC profile with CK7+ and CK20− was detected – that is more specific to the primitive pulmonary cancer, and the presence of only one sarcoma marker vementine+, desmine and actine−. Also the presence of KI 67: 20%, predicted the proliferative and great metastatic power of the lung tumor was observed.Additionally, lung cancer was the most frequent type and may develop in scleroderma as reported in most studies.This allows to conclude for primitive lung carcinoma revealed with vulvar metastasis after elimination of the possibility of vulvar sarcoma.The patient was treated by chemotherapy (Taxol/Platin) with partial response from the lung after 3 cycles and palliative radiotherapy in the vulva with a good response.This case described primary lung carcinoma associated with scleroderma, revealed by a vulvar metastasis, which may be related to the aggressiveness of lung cancer when the lung fibrosis follow-up is not performed well to detect early the development of lung tumors in the patient with systemic scleroderma. 相似文献96.
Christine Bouchardy Harriet Wikman Simone Benhamou Ari Hirvonen Pierre Dayer Kirsti Husgafvel-Pursiainen 《Biomarkers》2013,18(2):131-134
The CYP1A1 gene encoding for an enzyme involved in the metabolic activation of important tobacco carcinogens could be implicated in smoking-induced lung cancer. Given the strong association between tobacco smoking and lung cancer, the effect of tobacco smoke exposure has to be taken into account when studying the potential association between lung cancer and CYP1A1 genotypes. The effect of two CYP1A1 genetic polymorphisms (Mspl and IIe-Val) on lung cancer risk were evaluated using peripheral blood DNA from 150 lung cancer patients and 171 controls. The Mspl sitepresent allele was found among 19.3% of both cases and controls and the variant allele Val among 6.7% of cases and 8.8% of controls. Lung cancer risks associated with the Mspl site-present allele (OR= 0.9; 95%Cl: 0.5-1.8) or with the Val allele (OR= 0.8; 95%Cl: 0.3-1.9) were not increased after adjustment for tobacco and asbestos exposures. These results persisted when analyses were stratified on smoking status, daily consumption of tobacco or duration of smoking. Similar findings were obtained when squamous cell or small cell carcinomas were studied separately. This study thus suggests a minor role for the known CYP1A1 gene polymorphisms in predisposition to lung cancer among Caucasian populations. 相似文献
97.
Zheyong Huang Yunli Shen Hongmin Zhu Jianfeng Xu Yanan Song Xinying Hu Zhang Shuning Xiangdong Yang Aijun Sun Juying Qian Junbo Ge 《Experimental Animals》2013,62(3):197-203
Cell delivery via the retrograde coronary route boasts less vessel embolism, myocardial
injury, and arrhythmogenicity when compared with those via antegrade coronary
administration or myocardial injection. However, conventional insertion into the coronary
sinus and consequent bleeding complication prevent its application in small animals. To
overcome the complication of bleeding, we described a modified coronary retroinfusion
technique via the jugular vein route in rats with myocardial infarction (MI). A flexible
wire with a bent end was inserted into the left internal jugular vein and advanced slowly
along the left superior vena cava. Under direct vision, the wire was run into the left
cardiac vein by rotating the wire and changing the position of its tip. A fine tube was
then advanced along the wire to the left cardiac vein. This modified technique showed less
lethal hemorrhage than the conventional technique. Retroinfusion via transjugular catheter
enabled efficient fluid or cell dissemination to the majority areas of the free wall of
the left ventricle, covering the infarcted anterior wall. In conclusion, transjugular
cardiac vein catheterization may make retrocoronary infusion a more safe and practical
route for delivering cell, drug, and gene therapy into the infarcted myocardium of
rats. 相似文献
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The levels of benzo(a)pyrene diol-epoxide (BPDE)-DNA adducts and polycyclic aromatic hydrocarbons (PAH) were analysed in a limited number of samples of autoptic lung tissue obtained from non-professionally exposed male (n= 13) and female (n= 12) non-smokers in an attempt to evaluate the relationship between gender, lung PAH levels (n= 25) and susceptibility to BPDE-DNA adduct formation (n= 18). Lung concentrations of chrysene, benzo(g,h,i)perylene and benzo(a)pyrene were significantly higher in males than in females (P 相似文献
100.
Simone Benhamou Christine Bouchardy Anu Voho Katja Mitrunen Pierre Dayer Ari Hirvonen 《Biomarkers》2013,18(6):440-447
NAD(P)H:quinone oxidoreductase (NQO1) has been proposed to play a protective role against the toxic effects of benzo[a]pyrene quinones. The C609T base change in the NQO1 gene, resulting in a Pro187Ser amino acid change in the protein, has been associated with deficient enzyme activity. We examined whether this polymorphism modified the risks of smoking-related cancers in a case-control study involving patients with lung cancer (n = 150), laryngeal cancer (n = 129), oral/pharyngeal cancer (n = 121) and control individuals (n = 172), all Caucasian smokers. No statistically significant associations were observed between the NQO1 genotypes and smoking-related cancers, although the Ser/Ser genotype was associated with a tendency towards increased risk for lung cancer (odds ratio [OR] = 2.2, 95% confidence interval [CI] 0.7-6.7) and for oral/pharyngeal cancer (OR = 2.3, 95% CI 0.6-8.2). No significant interaction between the NQO1 genotype and either smoking exposure or GSTM1 genotype was found. Our results are consistent with the hypothesis that lack of NQO1 activity may be involved in some smoking-related cancers. However, they were based on small numbers of individuals with the putative atrisk genotype, and the associations did not reach statistical significance. Moreover, these results contrast with those observed in some other ethnic populations, where a protective effect of the NQO1 Ser allele was found. Further studies are therefore clearly needed for a better understanding of the potential role of NQO1 activity in tobacco-related cancers. 相似文献