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Online data collection could advantageously replace paper-and-pencil questionnaires in epidemiological studies by reducing the logistic burden, the cost and the duration of data processing. However, there is a need for studies comparing these new instruments to traditional ones. Our objective was to compare the web-based version of the NutriNet-Santé self-administered anthropometric questionnaire to the paper-based version. The questionnaire included 17 questions divided into subquestions (55 variables in all) dealing with height, weight, hip and waist circumferences, weight history, restrictive diet and weight self-perception. Both versions of the questionnaire were filled out by 147 volunteers (paper version first, N = 76, or web-based version first, N = 71) participating in the SU.VI.MAX (“Supplémentation en VItamines Minéraux et AntioXydants”) cohort (age-range: 49–75 years; men: 46.3%). At the end of the test, subjects filled in a “satisfaction” questionnaire giving their opinions and feelings about each version. Agreement was assessed by intraclass correlation coefficients (ICCs) and kappas. We also quantified the number of errors inherent in the paper version. Agreement between the two versions was high. ICCs ranged from 0.86 to 1.00. Kappas ranged from 0.69 to 1.00 for comparable variables. A total of 82 data entry mistakes (1.5% of total entries), 60 missing values (1.1%), 57 inconsistent values (1.1%) and 3 abnormal values (0.1%) were counted in the paper version (non-existent in the web-based version due to integrated controls). The web-based version was preferred by 92.2% of users. In conclusion, the quality of information provided by the web-based anthropometric questionnaire used in the NutriNet-Santé Study was equal to, or better than, that of the paper version, with substantial logistic and cost advantages.  相似文献   
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Intramuscular (i.m.) DNA vaccination induces strong cellular immune responses in the mouse, but only at DNA doses that cannot be achieved in humans. Because antigen expression is weak after naked DNA injection, we screened five nonionic block copolymers of poly(ethyleneoxide)-poly(propyleneoxide) (PEO-PPO) for their ability to enhance DNA vaccination using a β-galactosidase (βGal) encoding plasmid, pCMV-βGal, as immunogen. At a high DNA dose, formulation with the tetrafunctional block copolymers 304 (molecular weight [MW] 1,650) and 704 (MW 5,500) and the triblock copolymer Lutrol (MW 8,600) increased βGal-specific interferon-γ enzyme-linked immunosorbent spot (ELISPOT) responses 2–2.5-fold. More importantly, 704 allowed significant reductions in the dose of antigen-encoding plasmid. A single injection of 2 µg pCMV-βGal with 704 gave humoral and ELISPOT responses equivalent to those obtained with 100 µg naked DNA and conferred protection in tumor vaccination models. However, 704 had no adjuvant properties for βGal protein, and immune responses were only elicited by low doses of pCMV-βGal formulated with 704 if noncoding carrier DNA was added to maintain total DNA dose at 20 µg. Overall, these results show that formulation with 704 and carrier DNA can reduce the dose of antigen-encoding plasmid by at least 50-fold.  相似文献   
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Background: Keloids and hypertrophic scars (HSc) affect 4.5–16% of the population. Thus far, the different approaches of keloid treatment are not very efficient, with a 50% relapse rate and many ongoing researches are looking for simple, safe and more efficient therapeutic methods. Tacrolimus is an immunomodulator that could be useful in treating keloid. Objectives: The objective of this study is to evaluate the effectiveness of Tacrolimus in inhibiting HSc formation on rabbits' ears model and to check optical skin spectroscopy in tissue characterization. Methods: Our study was carried out on 20 New‐Zealand female white rabbits. HSc were obtained by wounding rabbits' ear. These wounds were treated with intradermal injections of tacrolimus (0.2–0.5 mg/cm2) or a vehicule. The assessment of treatment efficacy was performed by clinical examinations, histological assay and skin spectrometry. Results: Tacrolimus did not induce general or local side‐effects. The scar elevation index in treated subjects was half less than that of the untreated ones. Furthermore, dermal thickness and inflammatory cellular density were both significantly smaller for treated scars than for the control ones. In vivo optical skin spectroscopy can characterize hypertrophic and normal skin with high sensibility and specificity. Conclusion: Intradermal injection of tacrolimus at 0.5 mg/cm2 is an efficient way to prevent HSc in our experiment model and its tolerance is correct. Optical spectroscopy could be a good non‐invasive tool to evaluate HSc treatment. These promising results might be proposed for patients suffering from keloid.  相似文献   
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Cyclophosphamide (CPA) is a chemotherapeutic agent that is primarily activated in the liver by cytochrome P4502B6 (CYP2B6) and then transported to the tumor via blood flow. To prevent deleterious secondary effects, P450-based gene-directed enzyme prodrug therapy (GDEPT) consists of expressing CYP2B6 in tumor cells before CPA treatment. Given the relatively low affinity of CYP2B6 for CPA, the aim of our work was to modify CYP2B6 to increase its catalytic efficiency (V(max)/K(m)) to metabolize CPA into 4'-OH CPA. A molecular model of CYP2B6 was built, and four residues in close contact with the substrate were subjected to mutagenesis. Canine CYP2B11 exhibiting a particularly low K(m) to CPA, the amino acids exclusively present in the CYP2B11 substrate recognition sequences were substituted in human CYP2B6. All mutants (n = 26) were expressed in Saccharomyces cerevisiae and their enzymatic constants (K(m), V(max)) evaluated using CPA as substrate. Five mutants exhibited a 2- to 3-fold higher catalytic efficiency than wild-type CYP2B6. A double mutant, comprising the two most effective mutations, showed a 4-fold increase in K(m)/V(max). Molecular dynamic simulations of several mutants were found to be consistent with the observed modifications in catalytic efficiency. Finally, expression of the CYP2B6 114V/477W double mutant, contrary to wt CYP2B6, allowed switching of a resistant human head and neck cancer cell line (A-253) into a sensitive cell line toward CPA. Thus, we were able to obtain a new efficient CYP2B6 mutant able to metabolize CPA, an important step in the GDEPT strategy for human cancer treatment.  相似文献   
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Glutaric aciduria type I (GA-I, OMIM # 231670) is an inborn error of metabolism caused by a deficiency of glutaryl-CoA dehydrogenase (GCDH). Patients develop acute encephalopathic crises (AEC) with striatal injury most often triggered by catabolic stress. The pathophysiology of GA-I, particularly in brain, is still not fully understood.We generated the first knock-in rat model for GA-I by introduction of the mutation p.R411W, the rat sequence homologue of the most common Caucasian mutation p.R402W, into the Gcdh gene of Sprague Dawley rats by CRISPR/CAS9 technology. Homozygous Gcdhki/ki rats revealed a high excretor phenotype, but did not present any signs of AEC under normal diet (ND). Exposure to a high lysine diet (HLD, 4.7%) after weaning resulted in clinical and biochemical signs of AEC.A significant increase of plasmatic ammonium concentrations was found in Gcdhki/ki rats under HLD, accompanied by a decrease of urea concentrations and a concomitant increase of arginine excretion. This might indicate an inhibition of the urea cycle. Gcdhki/ki rats exposed to HLD showed highly diminished food intake resulting in severely decreased weight gain and moderate reduction of body mass index (BMI). This constellation suggests a loss of appetite. Under HLD, pipecolic acid increased significantly in cerebral and extra-cerebral liquids and tissues of Gcdhki/ki rats, but not in WT rats. It seems that Gcdhki/ki rats under HLD activate the pipecolate pathway for lysine degradation. Gcdhki/ki rat brains revealed depletion of free carnitine, microglial activation, astroglyosis, astrocytic death by apoptosis, increased vacuole numbers, impaired OXPHOS activities and neuronal damage. Under HLD, Gcdhki/ki rats showed imbalance of intra- and extracellular creatine concentrations and indirect signs of an intracerebral ammonium accumulation.We successfully created the first rat model for GA-I. Characterization of this Gcdhki/ki strain confirmed that it is a suitable model not only for the study of pathophysiological processes, but also for the development of new therapeutic interventions. We further brought up interesting new insights into the pathophysiology of GA-I in brain and periphery.  相似文献   
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Early Neolithic sedentary villagers started cultivating wild cereals in the Near East 11,500 y ago [Pre-Pottery Neolithic A (PPNA)]. Recent discoveries indicated that Cyprus was frequented by Late PPNA people, but the earliest evidence until now for both the use of cereals and Neolithic villages on the island dates to 10,400 y ago. Here we present the recent archaeological excavation at Klimonas, which demonstrates that established villagers were living on Cyprus between 11,100 and 10,600 y ago. Villagers had stone artifacts and buildings (including a remarkable 10-m diameter communal building) that were similar to those found on Late PPNA sites on the mainland. Cereals were introduced from the Levant, and meat was obtained by hunting the only ungulate living on the island, a small indigenous Cypriot wild boar. Cats and small domestic dogs were brought from the mainland. This colonization suggests well-developed maritime capabilities by the PPNA period, but also that migration from the mainland may have occurred shortly after the beginning of agriculture.  相似文献   
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Objectives  

Web-based studies nowadays raise a major interest as they can improve all steps involved in observational studies. Our objective was to compare the web-based version of the NutriNet-Santé self-administered socio-demographic and economic questionnaire with the traditional paper version.  相似文献   
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