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91.
Gonidi M Athanassiadou AM Patsouris E Tsipis A Dimopoulos S Kyriakidou V Chelidonis G Athanassiadou P 《Pathology, research and practice》2011,207(6):377-382
Mitochondria are the bioenergetic and metabolic centers of cells and play an important role in the regulation of cell death. The mitochondrial apoptosis pathway is controlled by the bcl-2 protein family. Overexpression of mitochondrial uncoupling protein 4 (UCP4) can promote proliferation and inhibit apoptosis and differentiation. Imprint smears obtained from 124 tumors were studied immunocytochemically, and results were correlated with prognostic markers. There were 112 ductal and 12 lobular carcinomas. The positivity of UCP4 was correlated with lymph node metastases (p = 0.005), positive ER and PR expression (p < 0.0001 for both), as well as positivity for p53 (p < 0.0001) and Ki-67 (p < 0.0001). Decreased expression of bcl-2 correlated with increased expression of UCP4 (p = 0.001). Regarding DNA ploidy, UCP4 positivity was correlated with aneuploid tumors (p = 0.002). Negative expression of bcl-2 was correlated with poorly differentiated carcinomas (p < 0.0001), as well as with positive expression of p53 (p < 0.0001) and Ki-67 (p < 0.0001). Logistic regression revealed that ploidy and p53 expression had an impact on UCP4. These findings encourage future investigations regarding the potential role of UCPs not only into mechanisms underlying breast cancer, but also as a novel candidate to the design and development of more effective therapeutic strategies. 相似文献
92.
93.
Recent advances in optical imaging for cervical cancer detection 总被引:1,自引:0,他引:1
Cervical cancer is one of the most common and lethal gynecological malignancies in both developing and developed countries,
and therefore, there is a considerable interest in early diagnosis and treatment of precancerous lesions. Although the current
standard care mainly based on cytology and colposcopy has reduced rates of cervical cancer morbidity and mortality, many lesions
are still missed or overcalled and referred for unnecessary biopsies. Optical imaging technologies, spectroscopy approaches
and high-resolution imaging methods are anticipated to improve the conventional cervical cancer screening providing in vivo
diagnosis with high sensitivity and specificity. Their concept is that morphologic and biochemical properties of the cervical
tissue are altered in response to its malignant transformation. In addition, contrast agents that target against specific
neoplastic biomarkers can enhance the effectiveness of this new technology. Due to the unprecedented growth of these optical
techniques accompanied probably by favorable cost-effectiveness, the primary detection of premalignant lesions may become
more accessible in both the developing and the developed countries and can offer see-to-treat workflows and early therapeutic
interventions. 相似文献
94.
Maria S. Iliou Panorea Kotantaki Dimitris Karamitros Magda Spella Stavros Taraviras Zoi Lygerou 《Mechanisms of ageing and development》2013,134(1-2):10-23
Cellular senescence is a permanent out-of-cycle state regulated by molecular circuits acting during the G1 phase of the cell cycle. Cdt1 is a central regulator of DNA replication licensing acting during the G1 phase and it is negatively controlled by Geminin. Here, we characterize the cell cycle expression pattern of Cdt1 and Geminin during successive passages of primary fibroblasts and compare it to tumour-derived cell lines. Cdt1 and Geminin are strictly expressed in distinct subpopulations of young fibroblasts, similarly to cancer cells, with Geminin accumulating shortly after the onset of S phase. Cdt1 and Geminin are down-regulated when primary human and mouse fibroblasts undergo replicative or stress-induced senescence. RNAi-mediated Geminin knock-down in human cells enhances the appearance of phenotypic and molecular features of senescence. Mouse embryonic fibroblasts heterozygous for Geminin exhibit accelerated senescence compared to control fibroblasts. In contrast, ectopic expression of Geminin in mouse embryonic fibroblasts delays the appearance of the senescent phenotype. Taken together, our data suggest that changes in Geminin expression levels affect the establishment of senescence pathways. 相似文献
95.
Effrossine A. Tsekoura Anastasia Konstantinidou Sofia Papadopoulou Stavros Athanasiou Nicholas Spanakis Dimitrios Kafetzis Aris Antsaklis Athanassios Tsakris 《Journal of medical virology》2010,82(8):1379-1383
Adenovirus is isolated frequently from the amniotic fluid and has been implicated in severe neonatal infections. A case control study was carried out to examine the association of detection of adenovirus in placentas with preterm birth and histological chorioamnionitis. Placentas from preterm and full term deliveries were collected prospectively. Preterm cases were divided into three subgroups according to the gestational age. PCR was carried out on placental tissues for the detection of adenovirus genome. Placentas were evaluated histologically for the presence of chorioamnionitis. Chi‐square and odds ratios (OR) were used to determine if detection of adenovirus is associated with preterm birth and histological evidence of inflammation. Seventy‐one preterm and 122 full term placentas were studied. Adenovirus genome was detected in 29 (40.8%) of preterm cases and in 25 (20.5%) of the full term controls (OR = 2.6; 95% CI, 1.4–5.1; P = 0.002). Detection of adenovirus in preterm placentas was significantly higher compared to full term particularly in the lower gestational age. Detection of adenovirus in placenta followed the seasonal variation of adenovirus infections. Thirty‐seven preterm and 21 full term placentas were also selected for paraffin inclusion and histological examination. Chorioamnionitis was present more frequently in preterm adenovirus‐positive placentas compared to preterm adenovirus‐negative placentas (75% vs. 36%; P = 0.026) as well as compared to term adenovirus‐positive placentas (75% vs. 19%; P = 0.003). This study demonstrates that adenovirus infection of the placenta is associated strongly with histological chorioamnionitis and preterm birth. J. Med. Virol. 82:1379–1383, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
96.
97.
Aboudola S Kotloff KL Kyne L Warny M Kelly EC Sougioultzis S Giannasca PJ Monath TP Kelly CP 《Infection and immunity》2003,71(3):1608-1610
There is a strong association between serum antibody responses to toxin A and protection against Clostridium difficile diarrhea. A parenteral C. difficile toxoid vaccine induced very-high-level responses to anti-toxin A immunoglobulin G (IgG) in the sera of healthy volunteers. After vaccination, the concentrations of anti-toxin A IgG in the sera of all 30 recipients exceeded the concentrations that were associated with protection in previous clinical studies. Furthermore, the median concentration of serum anti-toxin A IgG in the test group was 50-fold higher than the previous threshold. These findings support the feasibility of using a vaccine to protect high-risk individuals against C. difficile-associated diarrhea and colitis. 相似文献
98.
Stavros Petrou Helen Dakin Giselle Abangma Sarah Benge Ian Williamson 《Value in health》2010,13(5):543-551
ObjectivesTo estimate the cost-effectiveness of topical intranasal steroids for the treatment of otitis media with effusion (OME) in primary care from the perspective of the UK National Health Service.MethodsAn economic evaluation was conducted based on evidence from the double-blind, randomized, placebo-controlled GPRF [General Practice Research Framework] Nasal Steroids for Otitis Media with Effusion (GNOME) trial. Participants comprised 217 children aged 4–11 years who had at least one episode of otitis media or related ear problem in the previous 12 months and had tympanometrically confirmed bilateral OME. Children were randomly allocated to receive either mometasone furoate 50 µg or placebo spray once daily into each nostril for 3 months. The main outcome measure was the incremental cost per quality-adjusted life-year (QALY) gained for topical steroids compared with placebo. The nonparametric bootstrap method was used to present cost-effectiveness acceptability curves at alternative willingness to pay thresholds.ResultsChildren receiving topical steroids accrued nonsignificantly higher costs (incremental cost/child: £11, 95% confidence interval [CI]: ?£199 to £222) and nonsignificantly fewer QALYs (incremental QALY gain/child: ?0.0166, 95% CI: ?0.0652 to 0.0320) than those receiving placebo. Topical steroids had a 24.19% probability of being cost-effective at a £20,000 per QALY gained threshold, a 23.82% probability of being more effective and a 46.25% probability of being less costly. Sensitivity and subgroup analyses showed incremental costs and benefits to be highly sensitive to the methods used and the patient group considered, although differences between groups did not reach statistical significance in any analysis.ConclusionsTopical steroids are unlikely to be a cost-effective treatment for OME in general practice. 相似文献
99.
Giakoustidis D Papageorgiou G Iliadis S Kontos N Kostopoulou E Papachrestou A Tsantilas D Spyridis C Takoudas D Botsoglou N Dimitriadou A Giakoustidis E 《World journal of surgery》2002,26(7):872-877
The effect of intramuscular administration of high (30 mg/kg body weight for 3 days) or very high (300 mg/kg body weight for 3 days) doses of a-tocopherol to Wistar rats subjected to total severe warm hepatic ischemia and reperfusion was investigated. After a 60-minute period of total hepatic ischemia and 120 minutes of reperfusion, animals were killed, and liver samples were taken for determination of malondialdehyde (MDA) and histological examinations. Blood samples were also taken for assay of serum a-tocopherol, alanine transaminase (ALT), aspartate transaminase (AST), and lactic dehydrogenase (LDH). Additional animals were followed for a 7-day survival rate determination. Results showed that ischemia and reperfusion decreased the survival rate to 10%, whereas the levels of AST, ALT, and LDH in serum were increased compared with levels in animals that were sham operated. The MDA concentrations in liver were also increased, from 1.142 to 1.567 nmoles/g, whereas the levels of a-tocopherol in serum were decreased from 10.20 to 1.80 mmol/L. Pretreatment with a-tocopherol increased the viability to 50% and 70%, for the high and very high doses, respectively, and decreased the levels of AST, ALT, and LDH in serum. It also decreased the MDA concentrations in liver to 0.975 and 0.774 nmoles/g for the high and very high doses of a-tocopherol, respectively, whereas it increased the level of a-tocopherol in serum to 11.25 and 13.02 mmol/L for the high and very high doses, respectively. Histological examinations showed protection of the liver parenchyma in the animals treated with a-tocopherol. 相似文献
100.
PURPOSE: To evaluate the efficacy and safety of topical mitomycin C (MMC) for conjunctival-corneal intraepithelial neoplasia (CCIN). METHODS: One patient with primary CCIN received seven applications for 3 minutes of mitomycin C 0.02%, for 2 weeks, on alternative days. The size of the CCIN before and after the treatment and ophthalmic mitomycin C related complications were evaluated. RESULTS: The lesion started to regress during the second month after the last application of mitomycin C, and by the third month it disappeared completely. The patient remains disease free after 36 months follow up. The complications of mitomycin C included a mild tearing and a slight conjunctival hyperemia that resolved 7 days after the end of the therapy. CONCLUSION: Multiple applications of mitomycin C could be an effective treatment for selected cases of CCIN. 相似文献