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1.
2.
Adrenal function and aging have been the object of intense interest recently, especially as regards dehydroepiandrosterone sulfate (DHEA-S), which is of major importance, since it is distinct from cortisol and aldosterone in declining with age. In a group of healthy old Tunisians, we investigated the association between cortisol and DHEA-S, on the one hand, and age, sex, lifestyle, physical health, including the body mass index (BMI), physical activity, and smoking indicators, on the other hand. We observed that cortisol concentrations did not change with aging, while DHEA-S concentrations decrease with age in both sexes. Cortisol/DHEA-S ratio, however, increases with aging. Our results revealed that DHEA-S levels are affected neither by physical activity nor by weight. It appears also that current smoking could not affect the level of DHEA-S. Relationships were found between DHEA-S concentrations and BMI, then between DHEA-S levels and serum cholesterol, triglycerides and calcium. No modification in the morning serum cortisol was found to be associated with aging. Decrease in DHEA-S levels is, however, clearly associated with this phenomenon. High cortisol/DHEA-S ratio accelerates the occurrence of some adult diseases, such as diabetes mellitus, atherosclerosis, dementia, and osteoporosis. Generally, the adrenal insufficiency marked by a cognitive impairment, immune disorders, sexual dysfunction, and scores for depression and anxiety can be corrected by a replacement of deficient DHEA-S.  相似文献   
3.
This work deals with the phosphofructokinase enzyme (PFK) of the parasite Trypanosoma brucei. Inhibitors which are analogues of fructose-6-phosphate (F6P) derived from 2,5-anhydromannitol and therefore blocked in a closed conformation, both nonphosphorylated and phosphorylated, were designed. They provided information on this class of ATP-dependent PFK (structurally more similar to PPi-dependent PFKs revealing (i) an ordered mechanism, ATP binding first, inducing an essential conformational change to increase the affinity for F6P, and (ii) a rather hydrophobic environment at the ATP binding site. Nonphosphorylated mannitol derivatives bind at both the ATP and F6P binding sites, whereas the phosphorylated derivatives only bind at the ATP binding site. The inhibitors bearing an aromatic ring substituted at the meta position indicate a polar interaction with lysine 227, which is specific to T. brucei PFK and is replaced by a glycine in human PFK. This lysine can be irreversibly bound, leading to inhibition when an electrophilic carbon atom is beta to the meta position on the ring. This lysine was identified by site-directed mutagenesis. This first example of a specific irreversible inactivation of T. brucei PFK offers an opportunity to develop biologically active compounds against the sleeping sickness, the causative agent of which is the trypanosome.  相似文献   
4.
During olive oil production, large quantities of olive mill wastewater (OMW) are produced. This wastewater material, containing a high level of phenolic compounds, poses a serious environmental problem in almost all Mediterranean countries. Candida tropicalis YMEC14 was used as an extremophile strain to design an aerobic biotreatment process to detoxify OMW and reduce its polluting organic load. The process was enhanced by directing yeast metabolism towards biodegradation pathways using hexadecane as co-metabolite and by immobilizing yeast cells in calcium alginate beads. Under immobilization conditions, C. tropicalis YMEC14 grown at 40 degrees C in OMW supplemented with hexadecane resulted in 69.7%, 69.2% and 55.3% reduction of chemical oxygen demand, monophenols and polyphenols, respectively, after a 24-h fermentation cycle.  相似文献   
5.

Introduction

Alcohol use is one of the leading modifiable morbidity and mortality risk factors among young adults.

Study Design

2 parallel-group randomized controlled trial with follow-up at 1 and 6 months.

Setting/Participants

Internet based study in a general population sample of young men with low-risk drinking, recruited between June 2012 and February 2013.Intervention: Internet-based brief alcohol primary prevention intervention (IBI). The IBI aims at preventing an increase in alcohol use: it consists of normative feedback, feedback on consequences, calorific value alcohol, computed blood alcohol concentration, indication that the reported alcohol use is associated with no or limited risks for health. Intervention group participants received the IBI. Control group (CG) participants completed only an assessment.

Main Outcome Measures

Alcohol use (number of drinks per week), binge drinking prevalence. Analyses were conducted in 2014–2015.

Results

Of 4365 men invited to participate, 1633 did so; 896 reported low-risk drinking and were randomized (IBI: n = 451; CG: n = 445). At baseline, 1 and 6 months, the mean (SD) number of drinks/week was 2.4(2.2), 2.3(2.6), 2.5(3.0) for IBI, and 2.4(2.3), 2.8(3.7), 2.7(3.9) for CG. Binge drinking, absent at baseline, was reported by 14.4% (IBI) and 19.0% (CG) at 1 month and by 13.3% (IBI) and 13.0% (CG) at 6 months. At 1 month, beneficial intervention effects were observed on the number of drinks/week (p = 0.05). No significant differences were observed at 6 months.

Conclusion

We found protective short term effects of a primary prevention IBI.

Trial Registration

Controlled-Trials.com ISRCTN55991918  相似文献   
6.
Understanding the role of humans in the dispersal of predominantly animal pathogens is essential for their control. We used newly developed Bayesian phylogeographic methods to unravel the dynamics and determinants of the spread of dog rabies virus (RABV) in North Africa. Each of the countries studied exhibited largely disconnected spatial dynamics with major geopolitical boundaries acting as barriers to gene flow. Road distances proved to be better predictors of the movement of dog RABV than accessibility or raw geographical distance, with occasional long distance and rapid spread within each of these countries. Using simulations that bridge phylodynamics and spatial epidemiology, we demonstrate that the contemporary viral distribution extends beyond that expected for RABV transmission in African dog populations. These results are strongly supportive of human-mediated dispersal, and demonstrate how an integrated phylogeographic approach will turn viral genetic data into a powerful asset for characterizing, predicting, and potentially controlling the spatial spread of pathogens.  相似文献   
7.
AIM:To study the immunophenotype of hematopoietic progenitor cells from cord blood (CB) grafts (n = 39) in comparison with adult apheresis grafts (AG, n = 229) and pre-apheresis peripheral blood (PAPB) samples (n = 908) using flow cytometry analysis.METHODS: First, we performed a qualitative analysis of CD34+ cell sub-populations in both CB and PAPB grafts using the standardized ISHAGE protocol and a wide panel of 20 monoclonal antibodies. Next, we stud-ied some parameters, such as the age of mothers and the weight of newborns, which can influence the qual-ity and the quantity of CD34+ cells from CB. RESULTS: We found that the percentage of apoptotic cells was high in CB in comparison to PAPB (PAPB: 4.6% ± 2.6% vs CB: 53.4% ± 5.2%, P < 0.001). In CB, the weight of newborn and the age of the mother have the influence on CD34+ cells. The follow-up of Ag CD133in the ISHAGE double platform protocol in association with CD45, CD34 and the 7’AAD shows an equal rate between the two cell populations CD133+CD45+CD34+ high and CD34+CD45+ high with a higher percentage. So, is the inclusion of Ac CD133 necessary in the pres-ent panel included in the ISHAGE methodflLast part, we showed a signif icant presence of interferon γ in CB in comparison to PAPB, the annexin showing the high number of apoptotic cells in CB. CONCLUSION: This study demonstrates that many different obstetric factors must be taken into account when processing and cryo-banking umbilical CB units for transplantation.  相似文献   
8.
Constrictive remodeling after arterial injury is related to collagen accumulation. Cross-linking has been shown to induce a scar process in cutaneous wound healing and is increased after arterial injury. We therefore evaluated the effect of cross-linking inhibition on qualitative and quantitative changes in collagen, elastin, and arterial remodeling after balloon injury in the atherosclerotic rabbit model. Atherosclerotic-like lesions were induced in femoral arteries of 28 New Zealand White rabbits by a combination of air desiccation and a high-cholesterol diet. After 1 mo, balloon angioplasty was performed in both femoral arteries. Fourteen rabbits were fed beta-aminopropionitrile (beta-APN, 100 mg/kg) and compared with 14 untreated animals. The remodeling index, i.e., the ratio of external elastic lamina at the lesion site to external elastic lamina at the reference site, was determined 4 wk after angioplasty for both groups. Pyridinoline was significantly decreased in arteries from beta-APN-treated animals compared with controls, confirming inhibition of collagen cross-linking: 0.30 (SD 0.03) and 0.52 (SD 0.02) mmol/mol hydroxyproline, respectively (P = 0.002). Scanning and transmission electron microscopy showed a profound disorganization of collagen fibers in arteries from beta-APN-treated animals. The remodeling index was significantly higher in beta-APN-treated than in control animals [1.1 (SD 0.3) vs. 0.8 (SD 0.3), P = 0.03], indicating favorable remodeling. Restenosis decreased by 33% in beta-APN-treated animals: 32% (SD 16) vs. 48% (SD 24) (P = 0.02). Neointimal collagen density was significantly lower in beta-APN-treated animals than in controls: 23.0% (SD 3.8) vs. 29.4% (SD 4.0) (P = 0.004). These findings suggest that collagen and elastin cross-linking plays a role in the healing process via constrictive remodeling and restenosis after balloon injury in the atherosclerotic rabbit model.  相似文献   
9.
Sfar S  Hassen E  Saad H  Mosbah F  Chouchane L 《Cytokine》2006,35(1-2):21-28
OBJECTIVES: Vascular endothelial growth factor (VEGF) is a potent stimulus of angiogenesis that has an important role in many human malignancies including prostate carcinoma (PCa). We evaluated the role of the functional VEGF polymorphisms as genetic markers for PCa susceptibility and prognosis. METHODS: The study included 101 patients with PCa and [corrected] 100 age-matched healthy men. The VEGF genotypes -1154G>A were identified by allele-specific polymerase chain reaction (AS-PCR) and the genotypes -634G>C and 936C>T were identified by restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR). RESULTS: A negative association was found between VEGF -1154AA genotype and PCa risk (OR=0.27; P=0.009). Furthermore, the presence of the VEGF -1154A allele appeared to be associated with a decreased [corrected] risk of higher tumor grade (OR=0.37; P=0.01). A significant increased risk of prostate cancer was associated with the VEGF -634 (GC+CC) combined genotype (OR=1.95; P=0.02). The VEGF -634C allele was associated with the aggressive phenotype of prostate cancer as defined by the high histological grade (OR=3.48; P=0.007). The VEGF -1154A/-634G haplotype was negatively associated with PCa risk (OR=0.48; P=0.005) and high tumor grade compared to low grade (OR=0.37; P=0.02). CONCLUSIONS: Genetic variations in the VEGF may predict not only PCa risk but also tumor aggressiveness.  相似文献   
10.
Enteric viruses are shed in the feces and may be present in environmental waters. Their detection in wastewater, even at low concentration, is a major challenge. In this study, recoveries of Echovirus 7 (EV7), virions and RNA in wastewater, using virus concentration methods were determined to evaluate the detection of infectious viruses and the possibility of recovering viral genomes. Two virus concentration methods, PEG precipitation method and two-phase separation method, were applied to recovery experiments of EV7-virions from wastewater, in parallel with recovery experiments of EV7 RNA. The titration of EV7 virions was carried out by cell culture using human rhabdomyosarcoma tumor tissue and the EV7 RNA quantification was performed by real-time PCR. The mean recovery yields of EV7 virions using the PEG precipitation method and the two-phase separation method were 78.5?±?10.99 and 83.1?±?0.28?%, respectively. Besides, EV7 RNA recoveries obtained using the PEG precipitation method were four times higher than those using the two-phase separation method. According to our results, the two methods enable to concentrate both infectious viruses and viral genomes. Moreover, considering the protocol time and cost together with the ratio of the EV7 virion recovery to the EV7 RNA recovery, the two-phase separation method (83.1/2.71?%, or 30.6) seems to be more appropriate for selective concentration of viral virions than the PEG precipitation method (78.5/10.33?%, or 7.6).  相似文献   
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