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1.
DNA methylation is one of the most studied epigenetic mechanisms that play a pivotal role in regulating gene expression. The epigenetic component is strongly involved in aging-bone diseases, such as osteoporosis and osteoarthritis. Both are complex multi-factorial late-onset disorders that represent a globally widespread health problem, highlighting a crucial point of investigations in many scientific studies. In recent years, new findings on the role of DNA methylation in the pathogenesis of aging-bone diseases have emerged. The aim of this systematic review is to update knowledge in the field of DNA methylation associated with osteoporosis and osteoarthritis, focusing on the specific tissues involved in both pathological conditions.  相似文献   
2.
Polyamines are ubiquitous, low-molecular-weight aliphatic compounds, present in living organisms and essential for cell growth and differentiation. Copper amine oxidases (CuAOs) oxidize polyamines to aminoaldehydes releasing ammonium and hydrogen peroxide, which participates in the complex network of reactive oxygen species acting as signaling molecules involved in responses to biotic and abiotic stresses. CuAOs have been identified and characterized in different plant species, but the most extensive study on a CuAO gene family has been carried out in Arabidopsis thaliana. Growing attention has been devoted in the last years to the investigation of the CuAO expression pattern during development and in response to an array of stress and stress-related hormones, events in which recent studies have highlighted CuAOs to play a key role by modulation of a multilevel phenotypic plasticity expression. In this review, the attention will be focused on the involvement of different AtCuAOs in the IAA/JA/ABA signal transduction pathways which mediate stress-induced phenotypic plasticity events.  相似文献   
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The recent introduction of the Asian yellow-legged hornet, Vespa velutina, into Europe has raised concern regarding the threat to honeybees and the competition with the European hornet, Vespa crabro. The aim of this study was to investigated essential (Mg, Fe, Zn, Cu) and non-essential (Cd and Pb) elements in these two species. Element concentrations were determined in the whole body and separately in the head, thorax and abdomen using atomic absorption spectrometry (AAS). The changes in essential element concentration and speciation during metamorphosis were also studied using size exclusion chromatography followed by AAS and proteomic analysis. In both species, the essential elements were more concentrated in the abdomen due to the presence of fat bodies. Magnesium, Fe and Zn concentrations were significantly higher in V. crabro than in V. velutina and could have been related to the higher aerobic energy demand of the former species required to sustain foraging flight. Low concentrations of Cd and Pb were indicative of low environmental exposure. The concentration and speciation of essential elements, particularly Fe, varied among the developmental stages, indicating a modification of ligand preferences during metamorphosis. Overall, the results in the present study provide a better understanding of the hornet metal metabolism and a foundation for additional studies.  相似文献   
4.
Inherited cardiomyopathies are frequent causes of sudden cardiac death (SCD), especially in young patients. Despite at the autopsy they usually have distinctive microscopic and/or macroscopic diagnostic features, their phenotypes may be mild or ambiguous, possibly leading to misdiagnoses or missed diagnoses. In this review, the main differential diagnoses of hypertrophic cardiomyopathy (e.g., athlete’s heart, idiopathic left ventricular hypertrophy), arrhythmogenic cardiomyopathy (e.g., adipositas cordis, myocarditis) and dilated cardiomyopathy (e.g., acquired forms of dilated cardiomyopathy, left ventricular noncompaction) are discussed. Moreover, the diagnostic issues in SCD victims affected by phenotype-negative hypertrophic cardiomyopathy and the relationship between myocardial bridging and hypertrophic cardiomyopathy are analyzed. Finally, the applications/limits of virtopsy and post-mortem genetic testing in this field are discussed, with particular attention to the issues related to the assessment of the significance of the genetic variants.  相似文献   
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According to EC Reg. 2073/2005, Food Business Operators must demonstrate the safety of fermented sausages by using different approaches based on physico‐chemical analyses, predictive microbiology and Microbial Challenge Test. The aim of the present study was to investigate the application of different ingredients related to product safety on the development of key hurdles in Mediterranean‐style dry fermented sausages as “Salsiccia Sarda”. Weight loss, pH and aw were evaluated as ripening monitoring tool. Predictive mathematical models to evaluate the survival of Listeria monocytogenes complemented the present study. The evolution of aw and weight loss to values capable to support product's safety was shown to be closely related and was validated as a simple and effective monitoring tool of the Critical Control Point ripening. Based on the fermented sausage characteristics, “Salsiccia Sarda” at the end of ripening is unable to support the growth of the pathogen.

Practical applications

The correlation between weight loss and aw was validated as a simple and effective monitoring tool of the CCP ripening. The inclusion of a flavour stabilizer based on hydrolyzed pork proteins showed some effects on the aw evolution: the use of this additive can bring benefits in terms of assuring a constant safety of the final products and addressing the needs of reducing the cost of production. The empirical application of the hurdle technology in the production of “Salsiccia Sarda” highlights the need for Food Business Operators (FBOs) to carefully evaluate the physico‐chemical properties of the products and to control the ripening stage more effectively ensuring the production of fermented sausages with aw and pH values than can support product's safety.  相似文献   
7.
Hydrothermal carbonization of sewage sludge was carried out with the aim to evaluate the influence of process severity and initial solid content. Response surface methodology was applied to model yield and C yield responses. Enhanced dewaterability performance was recorded under mild processing conditions. The treatment promoted concentration and immobilization of Pb, Cd, Ni, Zn, and Cu. Variation of the solid content showed a stronger influence than severity on average yield and C yield. Higher heating values (HHVs) and energy retention efficiencies (EREs) of hydrochars obtained at the lowest solid content displayed the lowest values. Hence, the energy requirements of a first dewatering step should be compared with the related improvement in terms of HHV and ERE when sludge is used as feedstock.  相似文献   
8.
The thermal behavior of pure ZrO2 and four ZrO2-based organic-inorganic hybrids (OIHs) containing increasing amount (6, 12, 24 and 50?wt%) of poly(ε-caprolactone) (PCL) (named Z, ZP6, ZP12, ZP24 and ZP50 respectively) has been studied by simultaneous thermogravimetry (TG) and differential scanning calorimetry (DSC). The FTIR analysis of the gas mixture evolved at defined temperatures from the samples submitted to the TG experiments identified the mechanism of each thermally activated process. The obtained results suggest that the inorganic matrix of the OIHs prepared by this method exerts a stabilizing effect on the polymer, in particular for poor-PCL hybrid materials. In fact, the different thermal behavior of the ZP50 sample suggests that the polymer is not entirely bonded to the -OH groups of the zirconia matrix due to their saturation. For this reason a part of PCL is not affected by the stabilizing effect of the matrix and is subjected to thermal degradation. Finally, by observing their thermal behavior it was possible to select the most suitable temperatures for thermal pretreatment: 400, 600 and 1000?°C. The structural analysis by X-ray diffraction (XRD) revealed that at 400?°C the materials are amorphous, while at 600?°C they are mostly tetragonal, and the content of the tetragonal phase decreases with increasing the amount of PCL in the OIHs. All the materials treated at 1000?°C are monoclinic, but their crystallinity decreases with increasing the PCL content.  相似文献   
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