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81.
Deoxynivalenol (DON) remains one of the most concerning mycotoxins produced by the Fusarium genus due to the wide occurrence in highly consumed cereal-based food and its associated toxicological effects. Previous studies conducted in Spain and other European countries suggested that some vulnerable groups such as children could be exceeding the tolerable daily intakes. Thus, the aim of this study was to conduct a comprehensive and updated dietary exposure assessment study in Spain, with a specific analysis in the region of Catalonia. Cereal-based food samples collected during 2019 were analysed using liquid chromatography coupled to tandem mass spectrometry for multi-mycotoxin detection including DON and its main metabolites and derivatives. Consumption data were gathered from the nation-wide food surveys ENALIA and ENALIA2 conducted in Spain, and a specific survey conducted in Catalonia. The data were combined using deterministic and semi-parametric probabilistic methods. The results showed that DON was widely present in cereal-based food highly consumed in Spain and the Catalonia region. Exposure to DON among the adult population was globally low; however, among infants aged 3–9 years, it resulted in the median of 192 ng/kg body weight/day and the 95th percentiles of 604 ng/kg body weight/day, that would exceed the most conservative safety threshold for infants. Bread and pasta were the main contributing foodstuffs to the global exposure to DON, even among infants; thus, those foods should be considered a priority for food control or to develop strategies to reduce the exposure. In any case, further toxicological and epidemiological studies are required in order to refine the safety thresholds accounting for the sensitivity of the infant population.  相似文献   
82.
OBJECTIVEIn a large, multiethnic cohort of youths with obesity, we analyzed pathophysiological and genetic mechanisms underlying variations in plasma glucose responses to a 180 min oral glucose tolerance test (OGTT).RESEARCH DESIGN AND METHODSLatent class trajectory analysis was used to identify various glucose response profiles to a nine-point OGTT in 2,378 participants in the Yale Pathogenesis of Youth-Onset T2D study, of whom 1,190 had available TCF7L2 genotyping and 358 had multiple OGTTs over a 5 year follow-up. Insulin sensitivity, clearance, and β-cell function were estimated by glucose, insulin, and C-peptide modeling.RESULTSFour latent classes (1 to 4) were identified based on increasing areas under the curve for glucose. Participants in class 3 and 4 had the worst metabolic and genetic risk profiles, featuring impaired insulin sensitivity, clearance, and β-cell function. Model-predicted probability to be classified as class 1 and 4 increased across ages, while insulin sensitivity and clearance showed transient reductions and β-cell function progressively declined. Insulin sensitivity was the strongest determinant of class assignment at enrollment and of the longitudinal change from class 1 and 2 to higher classes. Transitions between classes 3 and 4 were explained only by changes in β-cell glucose sensitivity.CONCLUSIONSWe identified four glucose response classes in youths with obesity with different genetic risk profiles and progressive impairment in insulin kinetics and action. Insulin sensitivity was the main determinant in the transition between lower and higher glucose classes across ages. In contrast, transitions between the two worst glucose classes were driven only by β-cell glucose sensitivity.  相似文献   
83.
Advanced therapy medicinal products are human medical therapies based on genes, cells, or tissues, and due to their characteristics, they offer new innovative opportunities for the treatment of diseases and injuries, especially for diseases beyond the reach of traditional approaches. These therapies are at the forefront of innovation and have historically been very controversial, although in the last decade they have gained prominence while the number of new advanced therapies has increased every year. In this regard, despite the controversy they may generate, they are expected to dominate the market in the coming decades. Technologies based on advanced therapies are the present and future of medicine and bring us closer to the long-awaited precision medicine. Here we review the field as it stands today, with a focus on the molecular mechanisms that guided the different advanced therapies approved by the European Medicines Agency, their current status, and their legal approval.  相似文献   
84.
A number of DNA repair proteins also play roles in telomere metabolism. To investigate whether the accelerated telomere shortening reported in Fanconi anemia (FA) hematopoietic cells relates to a direct role of the FA pathway in telomere maintenance, we have analyzed telomere dynamics in Fancg-deficient mouse and human cells. We show here that both hematopoietic (stem and differentiated bone marrow cells, B and T lymphocytes) and nonhematopoietic (germ cells, mouse embryonic fibroblasts [MEFs]) Fancg(-/-) mouse cells display normal telomere length, normal telomerase activity, and normal chromosome end-capping, even in the presence of extensive clastogen-induced cytogenetic instability (mitomycin C [MMC], gamma-radiation). In addition, telomerase-deficient MEFs with humanlike telomere length and decreased Fancg expression (G5 Terc(-/-)/Fancg shRNA3 MEFs) display normal telomere maintenance. Finally, early-passage primary fibroblasts from patients with FA of complementation group G as well as primary human cells with reduced FANCG expression (FANCG shRNA IMR90 cells) show no signs of telomere dysfunction. Our observations indicate that accelerated telomere shortening in patients with FA is not due to a role of FANCG at telomeres but instead may be secondary to the disease. These findings suggest that telomerase-based therapies could be useful prophylactic agents in FA aplastic anemia by preserving their telomere reserve in the context of the disease.  相似文献   
85.
The ID (insertion/deletion) polymorphism of the ACE (angiotensin-converting enzyme) gene controls plasma ACE levels. Both have been correlated with ISR (in-stent restenosis) in preliminary analyses, but not confirmed in larger studies. In the present study, baseline and 6-month quantitative coronary analysis were performed in 897 patients who had stent implantation and the ID polymorphism genotyped. Plasma ACE levels were measured in 848 patients (95%). Restenosis rates among genotypes were 31.2% DD, 25.5% ID and 28.8% II (not significant). Plasma ACE levels were significantly higher in restenotic patients compared with patients without restenosis (30.7+/-18.6 units/l compared with 22.8+/-12.8 units/l; P=0.0001) and a strong independent predictor of ISR [OR (odds ratio)=3.70; 95% CI (confidence interval), 2.40-5.71; P<0.0001], except in diabetics. In the subgroup of diabetics and patients with AMI (acute myocardial infarction), the DD genotypes actually had a lower risk of ISR than the II genotypes (diabetics, OR=0.16; 95% CI, 0.04-0.69; P=0.014; and patients with AMI, OR=0.21; 95% CI, 0.061-0.749; P=0.016). After exclusion of diabetics and patients with AMI, ISR rates for genotypes in 632 patients were 31.7% DD, 24.3% ID and 17.6% II (P=0.02; DD compared with non-DD OR=1.57; 95% CI, 1.09-2.25). The association between the D allele and ISR observed in selected populations does not hold with a larger sample size. Other than sample size, clinical variables can modulate the association between ID polymorphism and ISR. Plasma ACE level is a risk factor for ISR, independently of the ID genotype.  相似文献   
86.
Shiga toxin type 2 (Stx2) produced by Escherichia coli O:157H7 can cause hemolytic-uremic syndrome in children, a disease for which there is neither a vaccine nor an effective treatment. This toxin consists of an enzymatically active A subunit and a pentameric B subunit responsible for the toxin binding to host cells, and also found to be immunogenic in rabbits. In this study we developed eukaryotic plasmids expressing the B subunit gene of Stx2 (pStx2B) and the B subunit plus the gene coding for the A subunit with an active-site deletion (pStx2 Delta A). Transfection of eukaryotic cells with these plasmids produced proteins of the expected molecular weight which reacted with specific monoclonal antibodies. Newborn and adult BALB/c mice immunized with two intramuscular injections of each plasmid, either alone or together with the same vector expressing the granulocyte and monocyte colony-stimulating factor (pGM-CSF), elicited a specific Th1-biased humoral response. The effect of pGM-CSF as an adjuvant plasmid was particularly notable in newborn mice and in pStx2B-vaccinated adult mice. Stx2-neutralizing activity, evaluated in vitro on VERO cell monolayers, correlated with in vivo protection. This is the first report using plasmids to induce a neutralizing humoral immune response against the Stx2.  相似文献   
87.
Two new sulfated triterpenes (1, 6) and four new sulfated triterpene glycosides (2-5) have been isolated from the aerial parts of Fagonia arabica. Their structures were established by spectroscopic data analysis. Compounds 1/2 and 3/4 are sulfated derivatives of the rare sapogenins 3beta,27-dihydroxyolean-12-en-28-oic acid and 3beta,27-dihydroxyurs-12-en-28-oic acid, respectively. Compound 5 is an unusual disulfated oleanene derivative characterized by the occurrence of a 13,18-double bond, while compound 6 is the first reported naturally occurring saturated and sulfated pentacyclic triterpene of the taraxastane series with a C-20,28 lactone unit.  相似文献   
88.
89.
ObjectivesTo verify if HDL3 Anionic Peptide Factor (HDL3-APF) is as an apolipoprotein that promotes the reverse cholesterol transport.Design and methodsWe investigated a possible association between plasma HDL3-APF concentration, cholesterol efflux from Fu5AH cells and cholesteryl ester transfer protein (CETP) activity in type 2 diabetic patients with coronary artery disease (CAD) (n = 36), those without CAD (n = 20), and 37 healthy subjects.ResultsPlasma APF concentrations were decreased in diabetics with CAD compared to controls (p < 0.01). Cellular cholesterol efflux was decreased in diabetics without and with CAD, (p < 0.01 and p < 0.001 respectively). CETP activity was significantly elevated in all patient groups. Multiple linear regression analysis shows that cholesterol efflux was independently and positively related only to APF concentrations in controls.ConclusionsAPF is likely to be a key independent factor for promoting cellular cholesterol efflux in healthy subjects. However this association is altered in type 2 diabetes.  相似文献   
90.
Objectives Artemether–lumefantrine (AL) is first‐line treatment for uncomplicated malaria in many African countries. Concomitant food consumption may affect absorption of lumefantrine but data in the most important target population, i.e. children, are lacking. Therefore, we evaluated the effect of food intake on oral lumefantrine bioavailability in African children with malaria. Methods In a randomised, investigator‐blinded, multicentre phase III efficacy trial, 899 infants and children with acute uncomplicated Plasmodium falciparum malaria received six doses of AL according to body weight over 3 days either as crushed tablets (Coartem®) or as dispersible tablets. Single blood samples were obtained for lumefantrine plasma concentration determination in a subset of 621 patients, and a two‐compartment pharmacokinetic model was constructed. Results The mean observed lumefantrine plasma concentration for crushed tablet and dispersible tablet, respectively, was 100% and 55% higher with a concomitant meal at the time of dose intake than when taken alone. Similarly, consumption of milk (the most common meal) increased model‐estimated lumefantrine bioavailability by 57% (90% CI: 29–96%) with crushed tablets and 65% (90% CI: 28–109%) with dispersible tablets compared to no food. The 28‐day PCR‐corrected cure rate (primary study endpoint) in the evaluable population was 582/587 [99.1% (95% CI: 98.0–99.7%)] and was not related to food intake. Conclusions AL was highly efficacious. Concomitant food intake increased lumefantrine absorption in children with malaria.  相似文献   
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