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41.
Maria Adelaide Marini Simona Frontoni Elena Succurro Franco Arturi Teresa Vanessa Fiorentino Angela Sciacqua Marta Letizia Hribal Francesco Perticone Giorgio Sesti 《PloS one》2013,8(10)
Reduced insulin clearance has been shown to predict the development of type 2 diabetes. Recently, it has been suggested that plasma glucose concentrations ≥8.6 mmol/l (155 mg/dl) at 1 h during an oral glucose tolerance test (OGTT) can identify individuals at high risk for type 2 diabetes among those who have normal glucose tolerance (NGT 1 h-high). The aim of this study was to examine whether NGT 1 h-high have a decrease in insulin clearance, as compared with NGT individuals with 1-h post-load glucose <8.6 mmol/l (l (155 mg/dl, NGT 1 h-low). To this end, 438 non-diabetic White individuals were subjected to OGTT and euglycemic-hyperinsulinemic clamp to evaluate insulin clearance and insulin sensitivity. As compared with NGT 1 h-low individuals, NGT 1 h-high had significantly higher 1-h and 2-h post-load plasma glucose and 2-h insulin levels as well as higher fasting glucose and insulin levels. NGT 1 h-high exhibited also a significant decrease in both insulin sensitivity (P<0.0001) and insulin clearance (P = 0.006) after adjusting for age, gender, adiposity measures, and insulin sensitivity. The differences in insulin clearance remained significant after adjustment for fasting glucose (P = 0.02) in addition to gender, age, and BMI. In univariate analyses adjusted for gender and age, insulin clearance was inversely correlated with body weight, body mass index, waist, fat mass, 1-h and 2-h post-load glucose levels, fasting, 1-h and 2-h post-load insulin levels, and insulin-stimulated glucose disposal. In conclusion, our data show that NGT 1 h-high have a reduction in insulin clearance as compared with NGT 1 h-low individuals; this suggests that impaired insulin clearance may contribute to sustained fasting and post-meal hyperinsulinemia. 相似文献
42.
Simona Nardozza Helen L. Boldingh M. Peggy Kashuba Regina Feil Dan Jones Amali H. Thrimawithana Hilary S. Ireland Marine Philippe Mark W. Wohlers Tony K. McGhie Mirco Montefiori John E. Lunn Andrew C. Allan Annette C. Richardson 《Plant, cell & environment》2020,43(4):819-835
Kiwifruit (Actinidia spp.) is a recently domesticated fruit crop with several novel-coloured cultivars being developed. Achieving uniform fruit flesh pigmentation in red genotypes is challenging. To investigate the cause of colour variation between fruits, we focused on a red-fleshed Actinidia chinensis var. chinensis genotype. It was hypothesized that carbohydrate supply could be responsible for this variation. Early in fruit development, we imposed high or low (carbon starvation) carbohydrate supplies treatments; carbohydrate import or redistribution was controlled by applying a girdle at the shoot base. Carbon starvation affected fruit development as well as anthocyanin and carbohydrate metabolite concentrations, including the signalling molecule trehalose 6-phosphate. RNA-Seq analysis showed down-regulation of both gene-encoding enzymes in the anthocyanin and carbohydrate biosynthetic pathways. The catalytic trehalose 6-phosphate synthase gene TPS1.1a was down-regulated, whereas putative regulatory TPS7 and TPS11 were strongly up-regulated. Unexpectedly, under carbon starvation MYB10, the anthocyanin pathway regulatory activator was slightly up-regulated, whereas MYB27 was also up-regulated and acts as a repressor. To link these two metabolic pathways, we propose a model where trehalose 6-phosphate and the active repressor MYB27 are involved in sensing the carbon starvation status. This signals the plant to save resources and reduce the production of anthocyanin in fruits. 相似文献
43.
Sara Bruschini Simona di Martino Maria Elena Pisanu Luigi Fattore Claudia De Vitis Valentina Laquintana Simonetta Buglioni Eugenio Tabbì Andrea Cerri Paolo Visca Gabriele Alessandrini Francesco Facciolo Christian Napoli Marcella Trombetta Antonio Santoro Anna Crescenzi Gennaro Ciliberto Rita Mancini 《Journal of cellular physiology》2020,235(3):1877-1887
44.
Messi Patrizia Bargellini Annalisa Anacarso Immacolata Marchesi Isabella Simona de Niederhäusern Bondi Moreno 《Archives of microbiology》2013,195(2):89-96
Three Legionella pneumophila strains isolated from municipal hot tap water during a multicentric Italian survey and belonging to serogroups 1, 6, 9 and the reference strain Philadelphia-1 were studied to determine the intracellular replication capability and the cytopathogenicity in human monocyte cell line U937 and in an Acanthamoeba polyphaga strain. Our results show that both serogroups 1 and Philadelphia-1 were able to multiply into macrophages inducing cytopathogenicity, while serogroup 6 and ever more serogroup 9 were less efficient in leading to death of the infected macrophages. Both serogroups 1 and 6 displayed a quite good capability of intracellular replication in A. polyphaga, although serogroup 1 was less cytopathogenic than serogroup 6. Serogroup 9, like Philadelphia-1 strain, showed a reduced efficiency of infection and replication and a low cytopathogenicity towards the protozoan. Our study suggests that bacterial pathogenesis is linked to the difference in the virulence expression of L. pneumophila serogroups in both hosts, as demonstrated by the fact that only L. pneumophila serogroup 1 shows the contextual expression of the two virulence traits. Serogroup 6 proves to be a good candidate as pathogen since it shows a good capacity for intracellular replication in protozoan. 相似文献
45.
46.
Daniela Calzia Simona Candiani Greta Garbarino Federico Caicci Silvia Ravera Maurizio Bruschi Lucia Manni Alessandro Morelli Carlo Enrico Traverso Giovanni Candiano Carlo Tacchetti Isabella Panfoli 《Cellular and molecular neurobiology》2013,33(5):637-649
Vertebrate retinal rod outer segments (OS) consist of a stack of disks surrounded by the plasma membrane, where phototransduction takes place. Energetic metabolism in rod OS remains obscure. Literature described a so-called Mg2+-dependent ATPase activity, while our previous results demonstrated the presence of oxidative phosphorylation (OXPHOS) in OS, sustained by an ATP synthetic activity. Here we propose that the OS ATPase and ATP synthase are the expression of the same protein, i.e., of F1Fo-ATP synthase. Imaging on bovine retinal sections showed that some OXPHOS proteins are expressed in the OS. Biochemical data on bovine purified rod OS, characterized for purity, show an ATP synthase activity, inhibited by classical F1Fo-ATP synthase inhibitors. Moreover, OS possess a pH-dependent ATP hydrolysis, inhibited by pH values below 7, suggestive of the functioning of the inhibitor of F1 (IF1) protein. WB confirmed the presence of IF1 in OS, substantiating the expression of F1Fo ATP synthase in OS. Data suggest that the OS F1Fo ATP synthase is able to hydrolyze or synthesize ATP, depending on in vitro or in vivo conditions and that the role of IF1 would be pivotal in the prevention of the reversal of ATP synthase in OS, for example during hypoxia, granting photoreceptor survival. 相似文献
47.
Mutations in neuronal voltage-gated sodium channel genes SCN1A, SCN2A, and SCN3A may play an important role in the etiology of neurological diseases and psychiatric disorders, besides various types of epilepsy. Here we describe a 3-year-old boy with autistic features, language delay, microcephaly and no history of seizures. Array-CGH analysis revealed an interstitial deletion of ~ 291.9 kB at band 2q24.3 disrupting the entire SCN2A gene and part of SCN3A. We discuss the effects of haploinsufficiency of SCN2A and SCN3A on the genetic basis of neurodevelopmental and neurobehavioral disorders and we propose that this haploinsufficiency may be associated not only with epilepsy, but also with autistic features. 相似文献
48.
Julio Caballero Szymon Zilocchi William Tiznado Daniela Rossi Simona Collina 《Molecular simulation》2013,39(3):227-235
Sigma-1 (σ1) affinities of methyl 2-(aminomethyl)-1-phenylcyclopropane-1-carboxylate (MAPCC) derivatives were modelled by the genetic algorithm with linear assignment of hypermolecular alignment of datasets (GALAHAD) and the comparative molecular field analysis (CoMFA)/comparative molecular similarity indices analysis (CoMSIA) methods. GALAHAD was used for deriving the 3D pharmacophore pattern that encompasses the most potent σ1 ligands within this series. Five MAPCC derivatives with a high σ1 affinity were used for deriving this model. The obtained model included a nitrogen atom, the hydrophobes and the hydrogen bond acceptor features; it was able to identify other potent σ1 ligands. On the other hand, CoMFA and CoMSIA methods were used for deriving quantitative structure–activity relationship (QSAR) models. All QSAR models were trained with 17 compounds, after which they were evaluated for predictive ability with additional five compounds. The best QSAR model was obtained by using CoMSIA, including steric, electrostatic and hydrophobic fields, and had a good predictive quality according to both internal and external validation criteria. In general, the models described herein provide meaningful information relevant for the rational design of new σ1 ligands. 相似文献
49.
50.
Capsule?Of 26 species of wintering waterbirds, 18 showed an increase in numbers, five showed a decrease and two showed no change. Aim?To assess long-term trends in the numbers and distribution of the 26 most abundant wintering waterbird species in the Czech Republic. Methods?We used International Waterbird Census data from between 48 and 639 wetland sites which had been counted annually in the Czech Republic from 1966 to 2008. From these data long-term changes in numbers and distributions were determined. Log-linear Poisson regression analysis was used to estimate missing data using trim software. The distribution of each species was described as the ratio of the number of sites occupied by that species to the total number of sites investigated. Results?Increasing trends were found for 18 species, five species were found to be declining, one species was stable and two species were found with uncertain trends. Wintering distributions (the ratio of sites occupied by a given species to the total number of sites counted) increased in 16 species and decreased in two species, broadly correlated with the species changes in numbers. Conclusion?In most species changes in numbers as well as changes in distribution followed the Western Palearctic population trends. Those species which increased were mainly piscivores and included geese, ducks and gulls. Scarcer species also exhibited an increase in numbers. The changes in numbers (both positive and negative) were more frequent among species associated with running water, whereas species which showed uncertain trends were more frequently recorded on standing water, which is more affected by variable weather conditions. 相似文献