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1.
Epithelial ovarian carcinoma (EOC), the major cause of gynaecological cancer death, is a heterogeneous disease classified into five subtypes. Each subtype has distinct clinical characteristics and is associated with different genetic risk factors and molecular events, but all are treated with surgery and platinum/taxane regimes. Tumour progression and chemoresistance is generally associated with major metabolic alterations, notably altered mitochondrial function(s). Here, we report for the first time that the expression of the mitochondrial regulators PGC1α and TFAM varies between EOC subtypes; furthermore, we have identified a profile in clear-cell carcinoma consisting of undetectability of PGC1α/TFAM, and low ERα/Ki-67. By contrast, high-grade serous carcinomas were characterised by a converse state of PGC1α/TFAM, ERα positivity and a high Ki-67 index. Interestingly, loss of PGC1α/TFAM and ERα was found also in a non-clear cell EOC cell line made highly resistant to platinum in vitro. Similar to clear-cell carcinomas, these resistant cells also showed accumulation of glycogen. Altogether, our data provide mechanistic insights into the chemoresistant nature of ovarian clear-cell carcinomas. Furthermore, these findings corroborate the need to take into account the diversity of EOC and to develop subtype specific treatment strategies.  相似文献   
2.
Apoptosis in the human endometrium plays an essential role for endometrial receptivity and early implantation. A dysbalance of pro- and anti-apoptotic events in the secretory endometrium seems to be involved in implantation disorders and consecutive pregnancy complications. However, little is known about the mechanisms regulating apoptosis-sensitivity in the human endometrium. Therefore this study was performed to identify molecular mechanisms underlying the resistance toward apoptosis in human endometrial stromal cells (ESCs). Human ESCs were isolated from hysterectomy specimens and used as undifferentiated cells or after decidualization in vitro. Cells were incubated with an activating anti-Fas antibody, tumor-necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), TNF-α and inhibitors of protein- and RNA-syntheses, a caspase-inhibitor and inhibitors of extracellular signal regulated kinase (Erk)1/2, nuclear factor (NF)-κB and Akt. Apoptosis was measured by flow cytometric detection of hypodiploid nuclei. Caspase-activity was detected by luminescencent assays. Several pro- and anti-apoptotic molecules and the activation of Erk1/2, NF-κB and Akt were analyzed by in-cell Western assays or flow cytometry. Inhibition of protein- and RNA-syntheses differentially sensitized human ESCs for death receptor-mediated apoptosis in a caspase-dependent manner, based on the up-regulation of the death receptors Fas and TRAIL-R2. The constitutive activity of Erk1/2 and NF-κB could be identified as a reason for the apoptosis-resistance of human ESCs. These results suggest the pro-survival signaling pathways Erk1/2 and NF-κB as key regulators of the sensitivity of human ESCs for death receptor-mediated apoptosis. The modulation of these pathways might play an important role in the physiology of implantation.  相似文献   
3.
Mutations that increase activity of Sir2 (silent information regulator 2) are associated with extended lifespan of yeast, fruit flies and worms. SIRT1, the human homolog of Sir2, that controls numerous physiological processes including the glucose metabolism, is considered a candidate gene for predicting variation in human lifespan. Whereas the role of Sir2 has been extensively investigated in model organisms, less is known about the relation between SIRT1 and lifespan in humans. In the current study we included 1,390 subjects from a general population-based cohort with 18 years of follow-up to investigate associations between variation in single nucleotide polymorphisms (SNPs) in the SIRT1 gene and human survival. Additionally in 535 male subjects with available data we investigated associations between SIRT1 and glucose tolerance. Carriers of the minor allele of rs12778366 had a significantly reduced mortality risk compared to the wild types: Hazard Ratio 0.69 (95% CI 0.50 to 0.96; p = 0.025). The directions of the effect were the same in females and males, never and ever smokers and the effect was significantly protective in overweight/obese subjects. Carriers of the minor allele of SNP rs12778366 had better glucose tolerance indicated by 0.34 mmol/l lower glucose levels compared to wild type subjects (p = 0.03). This study shows that SIRT1 affects human long-term survival and therefore may be an important factor in modulating lifespan not only in lower organisms, but also in humans.  相似文献   
4.

Background

Comparisons of objectively measured physical activity (PA) between residents of European countries measured concurrently with the same protocol are lacking. We aimed to compare PA between the seven European countries involved in the Food4Me Study, using accelerometer data collected remotely via the Internet.

Methods

Of the 1607 participants recruited, 1287 (539 men and 748 women) provided at least 3 weekdays and 2 weekend days of valid accelerometer data (TracmorD) at baseline and were included in the present analyses.

Results

Men were significantly more active than women (physical activity level = 1.74 vs. 1.70, p < 0.001). Time spent in light PA and moderate PA differed significantly between countries but only for women. Adherence to the World Health Organization recommendation to accumulate at least 150 min of moderate-equivalent PA weekly was similar between countries for men (range: 54–65%) but differed significantly between countries for women (range: 26–49%). Prevalence estimates decreased substantially for men and women in all seven countries when PA guidelines were defined as achieving 30 min of moderate and vigorous PA per day.

Conclusions

We were able to obtain valid accelerometer data in real time via the Internet from 80% of participants. Although our estimates are higher compared with data from Sweden, Norway, Portugal and the US, there is room for improvement in PA for all countries involved in the Food4Me Study.  相似文献   
5.
BackgroundIn general, smoking increases the risk of mortality. However, it is less clear how the relative risk varies by cause of death. The exact impact of changes in smoking habits throughout life on different mortality risks is less studied.MethodsWe studied the impact of baseline and lifetime smoking habits, and duration of smoking on the risk of all-cause mortality, mortality of cardiovascular diseases (CVD), chronic obstructive pulmonary disease (COPD), any cancer and of the four most common types of cancer (lung, colorectal, prostate, and breast cancer) in a cohort study (Vlagtwedde-Vlaardingen 1965–1990, with a follow-up on mortality status until 2009, n = 8,645). We used Cox regression models adjusted for age, BMI, sex, and place of residence. Since previous studies suggested a potential effect modification of sex, we additionally stratified by sex and tested for interactions. In addition, to determine which cause of death carried the highest risk we performed competing-risk analyses on mortality due to CVD, cancer, COPD and other causes.ResultsCurrent smoking (light, moderate, and heavy cigarette smoking) and lifetime persistent smoking were associated with an increased risk of all-cause, CVD, COPD, any cancer, and lung cancer mortality. Higher numbers of pack years at baseline were associated with an increased risk of all-cause, CVD, COPD, any cancer, lung, colorectal, and prostate cancer mortality. Males who were lifetime persistent pipe/cigar smokers had a higher risk of lung cancer [HR (95% CI) = 7.72 (1.72–34.75)] as well as all-cause and any cancer mortality. A longer duration of smoking was associated with a higher risk of COPD, any and lung cancer [HR (95% CI) = 1.06 (1.00–1.12), 1.03 (1.00–1.06) and 1.10 (1.03–1.17) respectively], but not with other mortality causes. The competing risk analyses showed that ex- and current smokers had a higher risk of cancer, CVD, and COPD mortality compared to all other mortality causes. In addition, heavy smokers had a higher risk for COPD mortality compared to cancer, and CVD mortality.ConclusionOur study indicates that lifetime numbers of cigarettes smoked and the duration of smoking have different impacts for different causes of mortality. Moreover, our findings emphasize the importance of smoking-related competing risks when studying the smoking-related cancer mortality in a general population and that smoking cessation immediately effectively reduces the risk of all-cause and any cancer mortality.  相似文献   
6.
A series of novel curcumin analogs were synthesized and screened for anti-cancer and anti-angiogenesis activities at Emory University and at the National Cancer Institute (NCI). These compounds are symmetrical alpha,beta-unsaturated and saturated ketones. The majority of the analogs demonstrated a moderate degree of anti-cancer activity. Compounds 10, 11, and 14 exhibited a high degree of cytotoxicity in the NCI in vitro anti-cancer cell line screen. In addition, this screen revealed that these compounds inhibit tumor cell growth with a higher potency than the commonly used chemotherapeutic drug, cisplatin. In independent in vitro screens conducted at Emory, the same compounds plus 4, 5, 8, 9, and 13 exhibited a high degree of cytotoxicity to tumor cells. Analogs that were effective in the anti-cancer screens were also effective in in vitro anti-angiogenesis assays. Compounds 4, 9, 11, and 14 were most effective in the anti-angiogenesis assays run at Emory. In the assays conducted by the NCI, compound 14 was almost as potent as the anti-angiogenic drug TNP-470, which has undergone clinical trials. Based on the favorable in vitro anti-cancer and anti-angiogenesis results with 14, further in vivo tests were conducted. This compound effectively reduced the size of human breast tumors grown in female athymic nude mice and showed little toxicity. This data, coupled with the remarkable in vitro data, suggests that compound 14 may potentially be an effective chemotherapeutic agent. As a follow-up, a 3D quantitative structure relationship based on 14 has been developed. It shows a cross-validated r2(q2) and a predictive r2(p2) = 0.71. COMPARE analysis suggests the compound to be a possible RNA/DNA antimetabolite, but also implies that the compound's cytotoxicity may arise from a presently unknown mechanism.  相似文献   
7.
Toll-like receptors (TLRs) participate in the defence against bacterial infections that are common in patients with Chronic Obstructive Pulmonary Disease (COPD). We studied all tagging SNPs in TLR2 and TLR4 and their associations with the level and change over time of both FEV(1) and sputum inflammatory cells in moderate-to-severe COPD. Nine TLR2 SNPs and 17 TLR4 SNPs were genotyped in 110 COPD patients. Associations of SNPs with lung function and inflammatory cells in induced sputum were analyzed cross-sectionally with linear regression and longitudinally with linear mixed-effect models. Two SNPs in TLR2 (rs1898830 and rs11938228) were associated with a lower level of FEV(1) and accelerated decline of FEV(1) and higher numbers of sputum inflammatory cells. None of the TLR4 SNPs was associated with FEV(1) level. Eleven out of 17 SNPs were associated with FEV(1) decline, including rs12377632 and rs10759931, which were additionally associated with higher numbers of sputum inflammatory cells at baseline and with increase over time. This is the first longitudinal study showing that tagging SNPs in TLR2 and TLR4 are associated with the level and decline of lung function as well as with inflammatory cell numbers in induced sputum in COPD patients, suggesting a role in the severity and progression of COPD.  相似文献   
8.

Background

Multidrug resistance-associated protein-1 (MRP1) protects against oxidative stress and toxic compounds generated by cigarette smoking, which is the main risk factor for chronic obstructive pulmonary disease (COPD). We have previously shown that single nucleotide polymorphisms (SNPs) in MRP1 significantly associate with level of FEV1 in two independent population based cohorts. The aim of our study was to assess the associations of MRP1 SNPs with FEV1 level, MRP1 protein levels and inflammatory markers in bronchial biopsies and sputum of COPD patients.

Methods

Five SNPs (rs212093, rs4148382, rs504348, rs4781699, rs35621) in MRP1 were genotyped in 110 COPD patients. The effects of MRP1 SNPs were analyzed using linear regression models.

Results

One SNP, rs212093 was significantly associated with a higher FEV1 level and less airway wall inflammation. Another SNP, rs4148382 was significantly associated with a lower FEV1 level, higher number of inflammatory cells in induced sputum and with a higher MRP1 protein level in bronchial biopsies.

Conclusions

This is the first study linking MRP1 SNPs with lung function and inflammatory markers in COPD patients, suggesting a role of MRP1 SNPs in the severity of COPD in addition to their association with MRP1 protein level in bronchial biopsies.  相似文献   
9.

Background

Cigarette smoking is the most important risk factor for Chronic Obstructive Pulmonary Disease (COPD). Only a subgroup of smokers develops COPD and it is unclear why these individuals are more susceptible to the detrimental effects of cigarette smoking. The risk to develop COPD is known to be higher in individuals with familial aggregation of COPD. This study aimed to investigate if acute systemic and local immune responses to cigarette smoke differentiate between individuals susceptible or non-susceptible to develop COPD, both at young (18-40 years) and old (40-75 years) age.

Methods

All participants smoked three cigarettes in one hour. Changes in inflammatory markers in peripheral blood (at 0 and 3 hours) and in bronchial biopsies (at 0 and 24 hours) were investigated. Acute effects of smoking were analyzed within and between susceptible and non-susceptible individuals, and by multiple regression analysis.

Results

Young susceptible individuals showed significantly higher increases in the expression of FcγRII (CD32) in its active forms (A17 and A27) on neutrophils after smoking (p = 0.016 and 0.028 respectively), independently of age, smoking status and expression of the respective markers at baseline. Smoking had no significant effect on mediators in blood or inflammatory cell counts in bronchial biopsies. In the old group, acute effects of smoking were comparable between healthy controls and COPD patients.

Conclusions

We show for the first time that COPD susceptibility at young age associates with an increased systemic innate immune response to cigarette smoking. This suggests a role of systemic inflammation in the early induction phase of COPD.

Trial registration

Clinicaltrials.gov: NCT00807469

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-014-0121-2) contains supplementary material, which is available to authorized users.  相似文献   
10.

Background

Buruli ulcer is a stigmatising disease treated with antibiotics and wound care, and sometimes surgical intervention is necessary. Permanent limitations in daily activities are a common long term consequence. It is unknown to what extent patients perceive problems in participation in social activities. The psychometric properties of the Participation Scale used in other disabling diseases, such as leprosy, was assessed for use in former Buruli ulcer patients.

Methods

Former Buruli ulcer patients in Ghana and Benin, their relatives, and healthy community controls were interviewed using the Participation Scale, Buruli Ulcer Functional Limitation Score, and the Explanatory Model Interview Catalogue to measure stigma. The Participation Scale was tested for the following psychometric properties: discrimination, floor and ceiling effects, internal consistency, inter-item correlation, item-total correlation and construct validity.

Results

In total 386 participants (143 former Buruli ulcer patients with their relatives (137) and 106 community controls) were included in the study. The Participation Scale displayed good discrimination between former Buruli ulcer patients and healthy community controls. No floor and ceiling effects were found. Internal consistency (Cronbach''s alpha) was 0.88. In Ghana, mean inter-item correlation of 0.29 and item-total correlations ranging from 0.10 to 0.69 were found while in Benin, a mean inter-item correlation of 0.28 was reported with item-total correlations ranging from −0.08 to 0.79. With respect to construct validity, 4 out of 6 hypotheses were not rejected, though correlations between various constructs differed between countries.

Conclusion

The results indicate the Participation Scale has acceptable psychometric properties and can be used for Buruli ulcer patients in Ghana and Benin. Future studies can use this Participation Scale to evaluate the long term restrictions in participation in daily social activities of former BU patients.  相似文献   
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