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101.
In recent years, special attention has been paid to the A3 adenosine receptor (A3AR) as a possible pharmacological target to treat intestinal inflammation. In this work, it was set up a novel method to quantify the concentration of a promising anti-inflammatory agent inside and outside of intestinal barrier using the everted gut sac technique. The compound chosen for the present study is one of the most potent and selective A3AR agonist reported so far, named AR 170 (N6-methyl-2-phenylethynyl-5′-N-methylcarboxamidoadenosine). In order to evaluate the intestinal absorption of AR 170 the radioligand binding assay in comparison with HPLC-DAD was used. Results showed that the compound is absorbed via passive diffusion by paracellular pathway. The concentrations determined in the serosal (inside the sac) fluid by radioligand binding assay are in good agreement with those obtained through the widely used HPLC/MS protocol, demonstrating the reliability of the method. It is worthwhile to note that the radioligand binding assay allows detecting very low concentrations of analyte, thus offering an excellent tool to measure the intestinal absorption of receptor ligands. Moreover, the AR 170 quantity outside the gut sac and the interaction with A3AR could presuppose good topical anti-inflammatory effects of this compound.  相似文献   
102.
The biotechnology for in vitro embryo production is becoming increasingly popular, being applied to humans and domestic animals. Embryo development can be achieved with either 20% or 5% oxygen tension. The extracellular vesicles (EVs) are secreted by different cell types and carry bioactive materials. Our objective was to determine the secretion pattern and micro RNA (miRNA) contents of EVs released in the bovine embryo culture environment—embryo and cumulus cell monolayer—on Days 3 and 7 of in vitro culture under two different oxygen tensions: High (20%) and low (5%). The EVs were isolated from the medium and analyzed to determine size, concentration, and miRNA levels. EVs concentration in low oxygen tension increased on Day 3 and decreased on Day 7. Additionally, altered EV miRNAs derived from the embryo‐cumulus culture medium were predicted to regulate survival and proliferation‐related pathways on Days 3 and 7. Moreover, miR‐210 levels decreased in EVs isolated from the culture medium under high oxygen tension suggesting that this miRNA can be used as a marker for normoxia since it is associated with low oxygen tension. In summary, this study provides knowledge of the oxygen tension effects on EVs release and content, and potentially, on cell‐to‐cell communication during in vitro bovine embryo production.  相似文献   
103.
It is a widely held belief that environmental contaminants contribute to the decline of amphibian populations. By spending most of their early life in water and later stages on the land, amphibians face a constant risk of exposure to pesticides and other chemical pollutants in both aquatic and terrestrial environments. This review presents an overview of the studies carried out in Italian amphibians to highlight hazardous effects of bioaccumulation of chemical pollutants in juveniles and adults in various contaminated environments. Further, the studies in the laboratory setting assessing the effects of chemical pollutants on reproductive and developmental processes are reported. These studies and their relative references have been summarized in a tabular form. Three prominent contaminant groups were identified: herbicides, insecticides, and fungicides; and only a few works reported the effects of other chemical pollutants. Each pollutant group has been delegated to a section. All through the literature survey, it is seen that interest in this topic in Italy is very recent and sparse, where only a few anuran and caudata species and only some chemical pollutants have been studied.  相似文献   
104.
Urothelial carcinoma (UC) is the most common bladder tumour. Proper treatment requires tumour resection for diagnosing its grade (aggressiveness) and stage (invasiveness). White‐light cystoscopy and histopathological examination are the gold standard procedures for clinical and histopathological diagnostics, respectively. However, cystoscopy is limited in terms of specificity, histology requires long tissue processing, both procedures rely on operator's experience. Multimodal optical spectroscopy can provide a powerful tool for detecting, staging and grading bladder tumours in a fast, reliable and label‐free modality. In this study, we collected fluorescence, Raman and reflectance spectra from 50 biopsies obtained from 32 patients undergoing transurethral resection of bladder tumour using a multimodal fibre‐probe. Principal component analysis allowed distinguishing normal from pathological tissues, as well as discriminating tumour stages and grades. Each individual spectroscopic technique provided high specificity and sensitivity in classifying all tissues; however, a multimodal approach resulted in a considerable increase in diagnostic accuracy (≥95%), which is of paramount importance for tumour grading and staging. The presented method offers the potential for being applied in cystoscopy and for providing an automated diagnosis of UC at the clinical level, with an improvement with respect to current state‐of‐the‐art procedures.   相似文献   
105.
Invasive animals depend on finding a balanced nutritional intake to colonize, survive, and reproduce in new environments. This can be especially challenging during situations of fluctuating cold temperatures and food scarcity, but phenotypic plasticity may offer an adaptive advantage during these periods. We examined how lifespan, fecundity, pre‐oviposition periods, and body nutrient contents were affected by dietary protein and carbohydrate (P:C) ratios at variable low temperatures in two morphs (winter morphs WM and summer morphs SM) of an invasive fly, Drosophila suzukii. The experimental conditions simulated early spring after overwintering and autumn, crucial periods for survival. At lower temperatures, post‐overwintering WM lived longer on carbohydrate‐only diets and had higher fecundity on low‐protein diets, but there was no difference in lifespan or fecundity among diets for SM. As temperatures increased, low‐protein diets resulted in higher fecundity without compromising lifespan, while high‐protein diets reduced lifespan and fecundity for both WM and SM. Both SM and WM receiving high‐protein diets had lower sugar, lipid, and glycogen (but similar protein) body contents compared to flies receiving low‐protein and carbohydrate‐only diets. This suggests that flies spend energy excreting excess dietary protein, thereby affecting lifespan and fecundity. Despite having to recover from nutrient depletion after an overwintering period, WM exhibited longer lifespan and higher fecundity than SM in favorable diets and temperatures. WM exposed to favorable low‐protein diet had higher body sugar, lipid, and protein body contents than SM, which is possibly linked to better performance. Although protein is essential for oogenesis, WM and SM flies receiving low‐protein diets did not have shorter pre‐oviposition periods compared to flies on carbohydrate‐only diets. Finding adequate carbohydrate sources to compensate protein intake is essential for the successful persistence of D. suzukii WM and SM populations during suboptimal temperatures.  相似文献   
106.
This review continues a general presentation of the metabolism of drugs and other xenobiotics started in a recent issue of Chemistry & Biodiversity. This Part 2 presents the numerous oxidoreductases involved, their nomenclature, relevant biochemical properties, catalytic mechanisms, and the very diverse reactions they catalyze. Many medicinally, environmentally, and toxicologically relevant examples are presented and discussed. Cytochromes P450 occupy a majority of the pages of Part 2, but a large number of relevant oxidoreductases are also considered, e.g., flavin-containing monooxygenases, amine oxidases, molybdenum hydroxylases, peroxidases, and the innumerable dehydrogenases/reductases.  相似文献   
107.
In Neo-Darwinism, variation and natural selection are the two evolutionary mechanisms that propel biological evolution. Variation implies changes in the gene pool of a population, enlarging the genetic variability from which natural selection can choose. But in the absence of natural selection, variation causes dissipation and randomization. Natural selection, in contrast, constrains this variability by decreasing the survival and fertility of the less-adapted organisms. The objective of this study is to propose a highly simplified simulation of variation and natural selection, and to relate the observed evolutionary changes in a population to its information content. The model involves an imaginary population of individuals. A quantifiable character allows the individuals to be categorized into bins. The distribution of bins (a histogram) was assumed to be Gaussian. The content of each bin was calculated after one to twelve cycles, each cycle spanning N generations (N being undefined). In a first study, selection was simulated in the absence of variation. This was modeled by assuming a differential fertility factor F that increased linearly from the lower bins (F<1.00) to the higher bins (F>1.00). The fertility factor was applied as a multiplication factor during each cycle. Several ranges of fertility were investigated. The resulting histograms became skewed to the right. In a second study, variation was simulated in the absence of selection. This was modeled by assuming that during each cycle each bin lost a fixed percentage of its content (variation factor Y) to its two adjacent bins. The resulting histograms became broader and flatter, while retaining their bilateral symmetry. Different values of Y were monitored. In a third study, various values of F and Y were combined. Our model allows the straightforward application of Shannon's equation and the calculation of a Shannon-entropy (SE) values for each histogram. Natural selection was, thus, shown to result in a progressive decrease in SE as a function of F. In other words, natural selection, when acting alone, progressively increased the information content of the population. In contrast, variation resulted in a progressive increase in SE as a function of Y. In other words, variation acting alone progressively decreased the information content of a population. When both factors, F and Y, were applied simultaneously, their relative weight determined the progressive change in SE.  相似文献   
108.
Recently, there are controversial opinions on the presence of Mycoplasmas/Ureaplasmas as colonizers or pathogens, and on the use of a targeted therapy. This study aimed to characterize Mycoplasmas/Ureaplasmas infections in reproductive age women, including the acquisition of sexually transmitted (ST) pathogens and poor birth outcomes. A total of 646 healthy Italian women fulfilled the inclusion criteria including 521 infertile women, 65 pregnant women, and 60 fertile women with identified risk factors and symptomatic for vaginitis/cervicitis. Multiplex and quantitative molecular techniques and direct automatic DNA sequencing were performed to assess the genome structure of Mycoplasma/Ureaplasma species and ST infected pathogens. Ureaplasma parvum serovar 3 represented the predominant colonizer of the urogenital tract of this series and the unique species significantly associated with ST pathogens coinfection (p < 0.01). U. parvum load >104 bacteria/ml, suggestive of active infection, has been measured only in asymptomatic high-risk human papillomavirus infected women (24.3%) and in 40% of women with idiopathic infertility. To note, 16% of the follicular fluid from these idiopathic women resulted infected with U. parvum. In conclusion, the present study focused the attention on U. parvum serovar 3 as emerging microorganism in sexually active women that may have the benefit of targeted therapy.  相似文献   
109.
Cyanobacteria have been considered as promising candidates for sustainable bioproduction from inexpensive raw materials, as they grow on light, carbon dioxide, and minimal inorganic nutrients. In this study, we present a genome-scale metabolic network model for Synechocystis sp. PCC 6803 and study the optimal design of the strain for ethanol production by using a mixed integer linear problem reformulation of a bilevel programming problem that identifies gene knockouts which lead to coupling between growth and product synthesis. Five mutants were found, where the in silico model predicts coupling between biomass growth and ethanol production in photoautotrophic conditions. The best mutant gives an in silico ethanol production of 1.054 mmol·gDW −1·h −1.  相似文献   
110.
Plant and Soil - The aims of this research were: i) to compare Cr, Cu, Ni and Pb concentrations in Quercus ilex L. leaves collected at urban/industrial and urban areas; ii) to investigate the main...  相似文献   
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