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991.

Purpose

To evaluate the long-term consequences of TNFα inhibitors on body composition and fat distribution, as well as changes in serum adipokines in patients with rheumatoid arthritis (RA) or ankylosing spondylitis (AS).

Methods

Eight patients with RA and twelve with AS requiring a TNFα inhibitor were prospectively followed for 2 years. Body composition was evaluated by dual X-ray absorptiometry and included measurements of total fat mass, lean mass, fat in the gynoid and android regions, and visceral fat. Serum leptin, total and high molecular weight (HMW) adiponectin, resistin, and ghrelin were also assessed.

Results

There was a significant gain in body mass index (p = 0.05) and a tendency for weight (p = 0.07), android fat (p = 0.07), and visceral fat (p = 0.059) increase in patients with RA, while in AS, total fat mass significantly increased (p = 0.02) with a parallel weight gain (p = 0.07). When examining the whole population of patients, we observed after 2 years a significant increase in body weight (+1.9 %; p = 0.003), body mass index (+2.5 %; p = 0.004), total fat mass (+11.1 %; p = 0.007), and fat in the android region (+18.3 %; p = 0.02). There was a substantial, albeit nonsignificant gain in visceral fat (+24.3 %; p = 0.088). Lean mass and gynoid fat were not modified. No major changes were observed for serum leptin, total adiponectin, and ghrelin, while HMW adiponectin and the HMW/total adiponectin ratio tended to decrease (?15.2 %, p = 0.057 and ?9.3 %, p = 0.067, respectively). Resistin decreased significantly (?22.4 %, p = 0.01).

Conclusions

Long-term TNFα inhibition in RA and AS is associated with a significant gain in fat mass, with a shift to the android (visceral) region. This fat redistribution raises questions about its influence on the cardiovascular profile of patients receiving these treatments.  相似文献   
992.
Experimental studies provided evidence about mechanisms by which cholesterol, especially high density lipoprotein cholesterol (HDL-C), could influence carcinogenesis, notably through antioxidant and anti-inflammatory properties. However, prospective studies that investigated the associations between specific lipid metabolism biomarkers and cancer risk provided inconsistent results. The objective was to investigate the prospective associations between total cholesterol (T-C), HDL-C, low density lipoprotein cholesterol, apolipoproteins A1 (apoA1) and B, and triglycerides and overall, breast and prostate cancer risk. Analyses were performed on 7,557 subjects of the Supplémentation en Vitamines et Minéraux Antioxydants Study, a nationwide French cohort study. Biomarkers of lipid metabolism were measured at baseline and analyzed regarding the risk of first primary incident cancer (N = 514 cases diagnosed during follow-up, 1994–2007), using Cox proportional hazards models. T-C was inversely associated with overall (HR1mmol/L increment = 0.91, 95 % CI 0.82–1.00; P = 0.04) and breast (HR1mmol/L increment = 0.83, 95 % CI 0.69–0.99; P = 0.04) cancer risk. HDL-C was also inversely associated with overall (HR1mmol/L increment = 0.61, 95 % CI 0.46–0.82; P = 0.0008) and breast (HR1mmol/L increment = 0.48, 95 % CI 0.28–0.83; P = 0.009) cancer risk. Consistently, apoA1 was inversely associated with overall (HR1g/L increment = 0.56, 95 % CI 0.39–0.82; P = 0.003) and breast (HR1g/L increment = 0.36, 95 % CI 0.18–0.73; P = 0.004) cancer risk. This prospective study suggests that pre-diagnostic serum levels of T-C, HDL-C and ApoA1 are associated with decreased overall and breast cancer risk. The confirmation of a role of cholesterol components in cancer development, by further large prospective and experimental studies, may have important implications in terms of public health, since cholesterol is already crucial in cardiovascular prevention.  相似文献   
993.
To reproduce a potential doping scenario, a 2 week administration of recombinant erythropoietin (rEPO) microdoses alone or in combination with growth hormone (GH) microdoses (three times a week) was performed on healthy and athletic male subjects. The aim of this study was to evaluate the identification capability of rEPO in samples obtained during and post treatment. Detection was tested in urine and blood using the antidoping techniques for rEPO detection (iso-electric focusing (IEF)-, sodium-dodecyl-sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE) and for some urine samples the sarcosyl (SAR)-PAGE method) with some improvements: for blood samples, instead of a simple concentration step, immuno-extraction of EPO was performed for all urines to limit protein contamination that can affect migration. In addition, elution buffer modifications also improved the quality of migration. The use of a recently validated biotinylated anti-EPO antibody simplified the protocols, allowing a single transfer step instead of a double-blot even by IEF with a lowered background. The criteria for suspicious blood and urine samples by IEF were also re-evaluated. While endogenous EPO was not decreased over the course of the study, EPO microdoses were detectable in blood and urine between 24 h and 72 h after an administration. Detection in urine in combination with SDS-PAGE was the most sensitive combination for prolonged detection (100% identification after 48 h, 91% after 72 h), slightly better than IEF. Urine samples also tested by SAR-PAGE indicated a similar sensitivity of detection to SDS-PAGE. GH co-administration had no impact on rEPO elimination/detection.  相似文献   
994.
Free fatty acids (FFAs) are metabolic intermediates that may be obtained through the diet or synthesized endogenously. In addition to serving as an important source of energy, they produce a variety of both beneficial and detrimental effects. They play essential roles as structural components of all cell membranes and as signaling molecules regulating metabolic pathways through binding to nuclear or membrane receptors. However, under conditions of FFAs overload, they become toxic, inducing ROS production, ER stress, apoptosis and inflammation. SFAs (saturated fatty acids), unlike UFAs (unsaturated fatty acids), have recently been proposed as triggers of the NLRP3 inflammasome, a molecular platform mediating the processing of IL-1β in response to infection and stress conditions. Interestingly, UFAs, especially ω-3 FAs, inhibit NLRP3 inflammasome activation in various settings. We focus on emerging models of NLRP3 inflammasome activation with a special emphasis on the molecular mechanisms by which FFAs modulate the activation of this complex. Taking into consideration the current literature and FFA properties, we discuss the putative involvement of mitochondria and the role of cardiolipin, a mitochondrial phospholipid, proposed to be sensed by NLRP3 after release, exposure and/or oxidation. Finally, we review how this SFA-mediated NLRP3 inflammasome activation contributes to the development of both insulin resistance and deficiency associated with obesity/type 2 diabetes. In this context, we highlight the potential clinical use of ω-3 FAs as anti-inflammatory compounds.  相似文献   
995.
Cancer stem cells (CSCs) are considered as the initiators of the carcinogenic process and are therefore emerging targets for innovative anticancer therapies. In order to evaluate the anticancer chemopreventive activity of flavagline derivatives, we used the pluripotent teratocarcinomal cell as a model of Oct4-expressing cancer stem-like cell and determined the underlying cellular and molecular mechanisms induced by a synthetic flavagline. We precisely investigated the effects of the flavagline derivative FL3 on the human embryonal carcinoma (EC) cell line NT2/D1 and compared the responses to those of a normal more restrictive pluripotent stem cell line (i.e. BJ fibroblast cell line). FL3 selectively inhibited the proliferation of NT2/D1 cells by inducing G1 phase cell cycle arrest in a dose-dependent manner. Moreover, FL3 treatment specifically triggered apoptosis in association with an induction of the phosphorylation of p38 mitogen-activated protein kinase (MAPK) and caspase-3 activation followed by a drastic downregulation of the master regulator of stemness Oct4. Forced inhibition of p38 MAPK activity by the specific pharmacological inhibitor SB203580 or by p38 MAPK gene knockdown using small-interfering RNA (siRNA) counteracted the effects of FL3, demonstrating that its chemopreventive action is related to growth inhibition and a p38-dependent caspase-3-dependent induction of apoptosis in Oct4-expressing CSCs. This study also shows that FL3 selectively kills poorly differentiated and highly aggressive carcinomal cells, but has little effect on normal stem-like cells. Thus FL3 offers great promise for cancer treatment since it is able to target the carcinogenic process without affecting normal cells.  相似文献   
996.
Spontaneous reporting is the primary method used in pharmacovigilance (PV) to detect drug safety signal. Specific criteria used in pharmacovigilance to prove accountability of a drug are rarely present in rare disease. The low number of alerts also makes it challenging. The aim of this commentary is to raise awareness among pharmacists on issues and opportunities for pharmacovigilance in rare diseases, taking pulmonary arterial hypertension (PAH) as example, from which a subset of cases are drug-induced. It is demonstrated how a dedicated program named VIGIAPATH created to reinforce pharmacovigilance of drug-induced pulmonary arterial hypertension at a national level, led to increase self-reporting and confirm safety signals. Thanks to a specific program such as VIGIAPATH, pharmacists can play an important role in communication with clinicians, patients and regulatory agencies, facilitating the detection of potential safety signals at an early stage in rare disease.  相似文献   
997.

AIM

The aim of the study was to report the first thorough characterization of the pharmacokinetics (PK) and pharmacodynamics (PD) of epoprostenol in an integrated manner.

METHOD

Twenty healthy male subjects received two formulations of i.v. epoprostenol, in a crossover design, in sequential infusions of 2, 4, 6 and 8 ng kg−1 min−1 for 2 h each. A sensitive assay was developed which allowed accurate PK characterization of epoprostenol via analysis of the concentration–time profiles of its two primary metabolites, 6-keto-prostacyclin F and 6,15-diketo-13,14-dihydro-prostacyclin F. PD parameters included cardiac output (CO), cardiac index (CIn) and heart rate (HR).

RESULTS

The pharmacokinetics of epoprostenol deviated slightly from dose-proportionality, probably due to a food effect. After infusion of the two formulations of epoprostenol, the t1/2 values expressed as geometric mean (95% confidence interval) were 0.25 h (0.14, 0.46) and 0.22 h (0.13, 0.38) for 6-keto-prostacyclin F, and 0.32 h (0.22, 0.45) and 0.34 h (0.26, 0.46) for 6,15-diketo-13,14-dihydro-prostacyclin F. A single compartment infusion model with first order elimination adequately described the PK of 6-keto-prostacyclin F. This model also characterized the food effect. Stepwise infusions with epoprostenol resulted in a progressive increase in CO, CIn and HR.

CONCLUSION

Of the two metabolites analyzed, the appearance of 6-keto-prostacyclin F in plasma was more closely associated with the haemodynamic effects of i.v. epoprostenol. PK and PD profiles showed that CIn relates proportionally and linearly to the plasma concentrations of 6-keto-prostacyclin F. These results suggest that 6-keto-prostacyclin F is a suitable surrogate marker of plasma concentrations of epoprostenol.  相似文献   
998.
AIM: To determine the economic impact (cost-benefit analysis) of childhood varicella vaccination, with the Oka/Merck varicella zoster virus vaccine live (Varivax) in Italy. METHODS: This analysis is based on an epidemiological model of varicella zoster virus (VZV) dynamics adapted to the Italian situation. Cost data (Euro, 2002 values) were collected through a literature review. Several vaccination scenarios were analysed: (i) routine vaccination programme for children aged 1-2 years with different levels of vaccination coverage (90%, 70% and 45%) without any catch-up programme; (ii) routine vaccination programme for children aged 1-2 years with different levels of vaccination coverage (90%, 70% and 45%) completed by a catch-up programme for 6-year-old children over the first 5 years of vaccine marketing; and (iii) routine vaccination programme for children aged 1-2 years with different levels of vaccination coverage (90%, 70% and 45%) completed by a catch-up programme during the first year of vaccine marketing for children aged 2-11 years. PERSPECTIVES: A societal perspective, including both direct and indirect costs, and a health-system perspective, limited to costs supported by Italian Health Authorities, were considered. RESULTS: A routine vaccination programme has a clearly positive impact on chickenpox morbidity. Respectively, 68% and 57% of chickenpox-related hospitalisations and deaths could be prevented with a 90% coverage rate. With vaccination costs being more than offset by a reduction in chickenpox treatment costs in the base case, such a programme could also induce savings from both a societal and a health-system perspective (40% and 12% savings, respectively for a 90% coverage rate). A lower coverage rate reduces cost savings, but there is still a 9% decrease in overall societal costs for a 45% coverage rate. Although the reduction in total societal costs was robust to the sensitivity analyses performed, a slight uncertainty remains regarding cost reduction from a health-system perspective. However, in this latter perspective, even in the worst-case scenario of the sensitivity analysis, routine vaccination programmes may be cost effective, the worst-case scenario for cost parameters leading to cost per life-year gained of Euro2853. Catch-up programmes combined with routine vaccination should lead to further cost reductions from a societal perspective: 15% for a massive catch-up during the first year of vaccine marketing compared with toddlers' vaccination alone, and 11% for a catch-up focused on 6-year-old children for a period of 5 years. However, the impact of catch-up programmes on the costs from an Italian health-system perspective remains close to zero (+/-1%). CONCLUSION: This model suggests, with its underlying assumptions and data, that routine ZVZ vaccination may be cost saving from both a societal and a health system perspective in the base case. In the worst-case scenario of the sensitivity analysis, vaccination remains cost effective.  相似文献   
999.
The hypothesis that elevated levels of ammonia-releasing compounds in tobacco and ammonia in mainstream (MS) smoke increase the rate and amount of nicotine evaporation from the particles of MS smoke aerosol was examined by kinetic modeling and experiments with MS cigarette smoke. Computational simulation of a kinetic mechanism describing volatile loss of nicotine, ammonia, and acetic acid from an aqueous solution was used to compute the time-dependent concentration of all species in the model. Because of the high volatility of ammonia relative to that of nicotine, variation over a wide range of initial ammonia concentration had no significant effect upon the rate of loss of nicotine from the model system. The effects of a variation in the volatile loss rate constant for ammonia and for the acid were examined. The simulations show that ammonia is lost from the model solution at a greater rate than nicotine and acid, and the loss of volatile acid has a significant role in the rate and amount of nicotine loss. Simulations with a model system undergoing a continuous steady addition of ammonia showed that high rates of ammonia addition could significantly increase the rate of nicotine volatile loss from the model solution. A series of smoking experiments was performed using blended cigarettes connected to a denuder tube. Deposition of smoke constituents can occur directly from the gas phase and by the deposition of smoke aerosol particles themselves. As nicotine exists >99% in the particle phase of MS smoke, in the absence of particle deposition, denuder tube deposition of nicotine occurs via the evaporation-deposition pathway. Solanesol, a nonvolatile tobacco and smoke terpene, was used to quantify the amount of particle deposition onto the denuder tube. The amount of ammonia deposited on the denuder tube was an order of magnitude greater than that of nicotine, showing that ammonia evaporates from the MS smoke particles much faster than does nicotine. The experimental results were supported and explained by the aqueous model simulations. Included in these experiments are cigarettes that differ in their MS smoke ammonia content by a factor of ca. five. However, an increased amount of MS smoke ammonia does not increase the rate of nicotine loss from the particles. The combined results support the conclusion that ammonia in mainstream smoke has little effect, if any, upon the rate and amount of nicotine evaporation from MS smoke particles.  相似文献   
1000.
A series of 5-alkylindolobenzazepin-7-ones was synthesized by Suzuki coupling between 3-iodoindole-2-carboxylates and the appropriate alpha-alkylbenzylamino o-boronic acids followed by cyclization to the lactam. Derivatives having a linear alkyl chain at C5 were found to be highly cytotoxic to KB cells with IC50 values in the 30-80 nM range. These compounds also inhibited the polymerization of tubulin with IC50's of 1-2 microM. Compound 4f (( S)-5-ethyl) showed comparable antiproliferative activities (IC50's of 30-70 nM) in a variety of cancer cell lines, cell growth being arrested at the G2/M phase. Compound 4f induced apoptosis in a dose-dependent manner in three different cancer cell lines and was shown to affect cell morphology in a manner consistent with its inhibitory action on tubulin polymerization. Using the experimental model of glioma grafted on the chick chorio-allantoic membrane, local treatment with compound 4f markedly reduced tumor progression.  相似文献   
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