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21.
Genome-wide association studies (GWAS) found locus 3p21.31 associated with severe COVID-19. CCR5 resides at the same locus and, given its known biological role in other infection diseases, we investigated if common noncoding and rare coding variants, affecting CCR5, can predispose to severe COVID-19. We combined single nucleotide polymorphisms (SNPs) that met the suggestive significance level (P ≤ 1 × 10−5) at the 3p21.31 locus in public GWAS datasets (6406 COVID-19 hospitalized patients and 902,088 controls) with gene expression data from 208 lung tissues, Hi-C, and Chip-seq data. Through whole exome sequencing (WES), we explored rare coding variants in 147 severe COVID-19 patients. We identified three SNPs (rs9845542, rs12639314, and rs35951367) associated with severe COVID-19 whose risk alleles correlated with low CCR5 expression in lung tissues. The rs35951367 resided in a CTFC binding site that interacts with CCR5 gene in lung tissues and was confirmed to be associated with severe COVID-19 in two independent datasets. We also identified a rare coding variant (rs34418657) associated with the risk of developing severe COVID-19. Our results suggest a biological role of CCR5 in the progression of COVID-19 as common and rare genetic variants can increase the risk of developing severe COVID-19 by affecting the functions of CCR5.  相似文献   
22.
Olive tree leaves (OTL) and grape marc (GM) are by-products with high linolenic (LNA) and linoleic (LA) acid content, respectively, which can be used as dietary ingredients to increase the cis-9 trans-11 conjugated linoleic acid (CLA) content of milk fat in sheep and goats. An experiment was conducted with 16 Friesian ewes and 16 Alpine goats to study the effect of OTL and GM inclusion in sheep and goat diets on their milk fatty acid profile, with emphasis on cis-9, trans-11 CLA and vaccenic acid (VA). Ewes and the goats were fed the control (C) diets from parturition to the 90 days in milk (DIM) and then both groups were divided into two sub-groups (treatments). The control groups of both species continued to be fed the C diets, whereas the treated groups were gradually switched over a 2-week period (DIM=91-105) from the C diets to that of treatment 1, which contained air-dried OTL. These OTL diets were fed ad libitum for 1 month (DIM=106-135). After that period, the same treated groups, after 2 weeks of gradual adaptation (DIM=136-150), were switched to treatment 2, which contained air-dried GM. The GM diets were fed ad libitum for 1 month (151-180 DIM). Concentrations of polyunsaturated fatty acids (PUFA) and mono-unsaturated fatty acids increased significantly in milk fat of sheep fed OTL v. C. For goats, only the PUFA in milk fat was increased by feeding OTL compared with C. Relative to C, GM increased significantly the concentration of PUFA only in milk fat of sheep. OTL and GM diets increased the cis-9, trans-11 CLA and VA content in milk fat, compared with C, only in sheep. GM caused a sharp increase in 18:0 only in sheep milk fat, while the OTL diet increased significantly the 18:0 in milk fat of goats. GM and OTL diets also had opposite effects on the 18:1/18:0 ratio of sheep milk fat. In conclusion, OTL and GM, when included in sheep diets altered the milk fatty acid profile with a pronounced increase in cis-9, trans-11 CLA and VA contents. The results show that the response of sheep and goats to OTL and GM diets was different, suggesting a species difference that needs further investigation.  相似文献   
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This work investigates the effect of potato presence on the degradation of extra virgin olive oil (EVOO) during repeated frying. For this reason the performance of EVOO during frying was compared with its performance during heating at frying temperatures. In order to make meaningful comparisons the temperature profiles obtained during the frying experiments were replicated during the heating experiments by means of a high energy exchange rate cooling/heating system. The effects of potato‐to‐oil ratio (1/7 and 1/35 kgpotatoes/Loil) and number (N) of batches (N = 0, 1, 0, 20, 30, 40) were examined. EVOO was analysed using high performance size exclusion chromatography (HPSEC). It was found that polymerisation products increased linearly during frying and heating and that they were not affected by potatoes presence at low ratio. The effect of potato presence became statistically significant (yet not remarkable) at the high ratio. Decomposition products increased during frying whereas they decreased during heating.  相似文献   
25.
Prato cheeses were manufactured using coagulant from Thermomucor indicae-seudaticae N31 or a commercial coagulant. Cheeses were characterised using the following analysis: yield; fat; acidity; moisture; ash; salt; pH; total nitrogen; total protein; NS-pH 4.6/NT*100; NS-TCA 12%/NT*100; casein electrophoresis; and RP-HPLC. The results were statistically analysed and revealed that the proteolytic indices were not significantly different throughout the 60 days of ripening of cheeses made with either coagulant. Even though there were some quantitative differences in the peptide profile of cheeses, the enzyme from T. indicae-seudaticae N31 was used in the production of good quality Prato cheese without having to change the established technological parameters of the process.  相似文献   
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This paper develops an empirical model to investigate the main determinants of household energy conservation patterns in Greece employing cross-section data. In the empirical analysis, household energy-conserving choices models are employed, using a discrete and a latent trait variable respectively as a dependent variable. The results show that socio-economic variables such as consumers’ income and family size are suitable to explain differences towards energy conservation preferences. In addition, the results suggest that electricity expenditures and age of the respondent are negatively associated with the number of energy-conserving actions that a consumer is willing to adopt. Finally, other variables such as environmental information feedback and consciousness of energy problems are characteristics of the energy-saver consumer. By evaluating consumer's decision-making process with regards to energy conservation measures, we are able to formulate and propose an effective energy conservation framework for Greece. An energy policy framework is among the main prerequisites not only to achieve sustainable development but also to maintain consumers’ quality of life.  相似文献   
28.
Gastrointestinal (GI) cancer constitutes a highly lethal entity among malignancies in the last decades and is still a major challenge for cancer therapeutic options. Despite the current combinational treatment strategies, including chemotherapy, surgery, radiotherapy, and targeted therapies, the survival rates remain notably low for patients with advanced disease. A better knowledge of the molecular mechanisms that influence tumor progression and the development of optimal therapeutic strategies for GI malignancies are urgently needed. Currently, the development and the assessment of the efficacy of immunotherapeutic agents in GI cancer are in the spotlight of several clinical trials. Thus, several new modalities and combinational treatments with other anti-neoplastic agents have been identified and evaluated for their efficiency in cancer management, including immune checkpoint inhibitors, adoptive cell transfer, chimeric antigen receptor (CAR)-T cell therapy, cancer vaccines, and/or combinations thereof. Understanding the interrelation among the tumor microenvironment, cancer progression, and immune resistance is pivotal for the optimal therapeutic management of all gastrointestinal solid tumors. This review will shed light on the recent advances and future directions of immunotherapy for malignant tumors of the GI system.  相似文献   
29.
Higher manganese silicides (HMS) are promising alternative materials for middle to high temperature thermoelectric applications as a low-cost, non-toxic and highly stable p-type leg. Many of the preparation methods that have been reported previously require long-time and energy consuming processes, as well as expensive equipment, and often do not result in a material of sufficient quality. In this study, the simple, cost-effective and eco-friendly technique of pack cementation is applied. HMS powders synthesized at different experimental conditions are studied and compared considering their structure, composition, short-term thermal stability in air and thermoelectric properties. X-ray diffraction analysis, X-ray photoelectron spectroscopy, scanning electron microscopy, thermogravimetry and thermoelectric measurements (in terms of Seebeck coefficient, electrical and thermal conductivity) were employed for the characterization of the material and evaluation of its performance. All samples were identified as HMS and only some negligible traces of MnSi were detected. They moderately oxidize when heated non-isothermally under air atmosphere up to 1473 K, while the presence of HMS remains dominant even at such high temperatures. Their thermoelectric properties were remarkable for an undoped material, with a maximum figure of merit (ZT) of 0.47 at 777 K. Pack cementation appeared to have a great potential as the synthesis route of high-efficiency HMS.  相似文献   
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