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41.
Tartary buckwheat (Fagopyrum tataricum Gaertn.) is grown in eastern and central Asia (the Himalayan regions of China, Nepal, Bhutan and India) and in central and eastern Europe (Luxemburg, Germany, Slovenia and Bosnia and Herzegovina). It is known for its high concentration of rutin and other phenolic metabolites. Besides the grain, the other aboveground parts of Tartary buckwheat contain rutin as well. After the mixing of the milled buckwheat products with water, the flavonoid quercetin is obtained in the flour–water mixture, a result of rutin degradation by rutinosidase. Heating by hot water or steam inactivates the rutin-degrading enzymes in buckwheat flour and dough. The low buckwheat protein digestibility is due to the high content of phenolic substances. Phenolic compounds have low absorption after food intake, so, after ingestion, they remain for some time in the gastrointestinal tract. They can act in an inhibitory manner on enzymes, degrading proteins and other food constituents. In common and Tartary buckwheat, the rutin and quercetin complexation with protein and starch molecules has an impact on the in vitro digestibility and the appearance of resistant starch and slowly digestible proteins. Slowly digestible starch and proteins are important for the functional and health-promoting properties of buckwheat products.  相似文献   
42.
Galectins are a family of conserved soluble proteins defined by an affinity for β-galactoside structures present on various glycoconjugates. Over the past few decades, galectins have been recognized as important factors for successful implantation and maintenance of pregnancy. An increasing number of studies have demonstrated their involvement in trophoblast cell function and placental development. In addition, several lines of evidence suggest their important roles in feto-maternal immune tolerance regulation and angiogenesis. Changed or dysregulated galectin expression is also described in pregnancy-related disorders. Although the data regarding galectins’ clinical relevance are still at an early stage, evidence suggests that some galectin family members are promising candidates for better understanding pregnancy-related pathologies, as well as predicting biomarkers. In this review, we aim to summarize current knowledge of galectins in early pregnancy as well as in pregnancy-related pathologies.  相似文献   
43.
Amyloidosis is a rare disease caused by the misfolding and extracellular aggregation of proteins as insoluble fibrillary deposits localized either in specific organs or systemically throughout the body. The organ targeted and the disease progression and outcome is highly dependent on the specific fibril-forming protein, and its accurate identification is essential to the choice of treatment. Mass spectrometry-based proteomics has become the method of choice for the identification of the amyloidogenic protein. Regrettably, this identification relies on manual and subjective interpretation of mass spectrometry data by an expert, which is undesirable and may bias diagnosis. To circumvent this, we developed a statistical model-assisted method for the unbiased identification of amyloid-containing biopsies and amyloidosis subtyping. Based on data from mass spectrometric analysis of amyloid-containing biopsies and corresponding controls. A Boruta method applied on a random forest classifier was applied to proteomics data obtained from the mass spectrometric analysis of 75 laser dissected Congo Red positive amyloid-containing biopsies and 78 Congo Red negative biopsies to identify novel “amyloid signature” proteins that included clusterin, fibulin-1, vitronectin complement component C9 and also three collagen proteins, as well as the well-known amyloid signature proteins apolipoprotein E, apolipoprotein A4, and serum amyloid P. A SVM learning algorithm were trained on the mass spectrometry data from the analysis of the 75 amyloid-containing biopsies and 78 amyloid-negative control biopsies. The trained algorithm performed superior in the discrimination of amyloid-containing biopsies from controls, with an accuracy of 1.0 when applied to a blinded mass spectrometry validation data set of 103 prospectively collected amyloid-containing biopsies. Moreover, our method successfully classified amyloidosis patients according to the subtype in 102 out of 103 blinded cases. Collectively, our model-assisted approach identified novel amyloid-associated proteins and demonstrated the use of mass spectrometry-based data in clinical diagnostics of disease by the unbiased and reliable model-assisted classification of amyloid deposits and of the specific amyloid subtype.  相似文献   
44.
Osmotic changes are common challenges for marine microorganisms. Bacteria have developed numerous ways of dealing with this stress, including reprogramming of global cellular processes. However, specific molecular adaptation mechanisms to osmotic stress have mainly been investigated in terrestrial model bacteria. In this work, we aimed to elucidate the basis of adjustment to prolonged salinity challenges at the proteome level in marine bacteria. The objects of our studies were three representatives of bacteria inhabiting various marine environments, Shewanella baltica, Vibrio harveyi and Aliivibrio fischeri. The proteomic studies were performed with bacteria cultivated in increased and decreased salinity, followed by proteolytic digestion of samples which were then subjected to liquid chromatography with tandem mass spectrometry analysis. We show that bacteria adjust at all levels of their biological processes, from DNA topology through gene expression regulation and proteasome assembly, to transport and cellular metabolism. The finding that many similar adaptation strategies were observed for both low- and high-salinity conditions is particularly striking. The results show that adaptation to salinity challenge involves the accumulation of DNA-binding proteins and increased polyamine uptake. We hypothesize that their function is to coat and protect the nucleoid to counteract adverse changes in DNA topology due to ionic shifts.  相似文献   
45.
Based on the mechanism of neuropathic pain induction, a new type of bifunctional hybrid peptidomimetics was obtained for potential use in this type of pain. Hybrids consist of two types of pharmacophores that are connected by different types of linkers. The first pharmacophore is an opioid agonist, and the second pharmacophore is an antagonist of the pronociceptive system, i.e., an antagonist of the melanocortin-4 receptor. The results of tests in acute and neuropathic pain models of the obtained compounds have shown that the type of linker used to connect pharmacophores had an effect on antinociceptive activity. Peptidomimetics containing longer flexible linkers were very effective at low doses in the neuropathic pain model. To elucidate the effect of linker lengths, two hybrids showing very high activity and two hybrids with lower activity were further tested for affinity for opioid (mu, delta) and melanocortin-4 receptors. Their complexes with the target receptors were also studied by molecular modelling. Our results do not show a simple relationship between linker length and affinity for particular receptor types but suggest that activity in neuropathic pain is related to a proper balance of receptor affinity rather than maximum binding to any or all of the target receptors.  相似文献   
46.
This study investigates the effect of Dexamethasone (Dex) treatment on blood and skeletal muscle metabolites level and skeletal muscle activity of enzymes related to energy metabolism after long-duration swimming. To evaluate whether Dex treatment, swimming, and combining these factors act on analyzed data, rats were randomly divided into four groups: saline treatment non-exercise and exercise and Dex treatment non-exercised and exercised. Animals in both exercised groups underwent long-lasting swimming. The concentration of lipids metabolites, glucose, and lactate were measured in skeletal muscles and blood according to standard colorimetric and fluorimetric methods. Also, activities of enzymes related to aerobic and anaerobic metabolism were measured in skeletal muscles. The results indicated that Dex treatment induced body mass loss and increased lipid metabolites in the rats’ blood but did not alter these changes in skeletal muscles. Interestingly, prolonged swimming applied after 9 days of Dex treatment significantly intensified changes induced by Dex; however, there was no difference in skeletal muscle enzymatic activities. This study shows for the first time the cumulative effect of exercise and Dex on selected elements of lipid metabolism, which seems to be essential for the patient’s health due to the common use of glucocorticoids like Dex.  相似文献   
47.
In bacteria, the DsbA oxidoreductase is a crucial factor responsible for the introduction of disulfide bonds to extracytoplasmic proteins, which include important virulence factors. A lack of proper disulfide bonds frequently leads to instability and/or loss of protein function; therefore, improper disulfide bonding may lead to avirulent phenotypes. The importance of the DsbA function in phytopathogens has not been extensively studied yet. Dickeya solani is a bacterium from the Soft Rot Pectobacteriaceae family which is responsible for very high economic losses mainly in potato. In this work, we constructed a D. solani dsbA mutant and demonstrated that a lack of DsbA caused a loss of virulence. The mutant bacteria showed lower activities of secreted virulence determinants and were unable to develop disease symptoms in a potato plant. The SWATH-MS-based proteomic analysis revealed that the dsbA mutation led to multifaceted effects in the D. solani cells, including not only lower levels of secreted virulence factors, but also the induction of stress responses. Finally, the outer membrane barrier seemed to be disturbed by the mutation. Our results clearly demonstrate that the function played by the DsbA oxidoreductase is crucial for D. solani virulence, and a lack of DsbA significantly disturbs cellular physiology.  相似文献   
48.
Ischemic stroke is a disease related to abnormal blood flow that leads to brain dysfunction. The early and late phases of the disease are distinguished. A distinction is made between the early and late stages of the disease, and the best effect in treating an ischemic stroke is usually achieved within the first hours after the onset of symptoms. This review looked at studies platelet activity monitoring studies to determine the risks and benefits of various approaches including antiplatelet therapy. A study was conducted on recently published literature based on PRISMA. This review includes 32 research articles directly addressing the importance of monitoring platelet function during antiplatelet therapy (dual or monotherapy) after ischemic stroke. In patients with transient ischemic attack or ischemic stroke, antiplatelet therapy can reduce the risk of stroke by 11–15%, assuming that patients respond well. Secondary prevention results are dependent on platelet reactivity, meaning that patients do not respond equally to antiplatelet therapy. It is very important that aspirin-resistant patients can benefit from the use of dual antiplatelet therapy. The individualized approach to secondary stroke prevention is to administer the most appropriate drug at the correct dose and apply the optimal therapeutic procedure to the individual patient.  相似文献   
49.
Antimicrobial peptides (AMPs) constitute a promising tool in the development of novel therapeutic agents useful in a wide range of bacterial and fungal infections. Among the modifications improving pharmacokinetic and pharmacodynamic characteristics of natural AMPs, an important role is played by lipidation. This study focuses on the newly designed and synthesized lipopeptides containing multiple Lys residues or their shorter homologues with palmitic acid (C16) attached to the side chain of a residue located in the center of the peptide sequence. The approach resulted in the development of lipopeptides representing a model of surfactants with two polar headgroups. The aim of this study is to explain how variations in the length of the peptide chain or the hydrocarbon side chain of an amino acid residue modified with C16, affect biological functions of lipopeptides, their self-assembling propensity, and their mode of action.  相似文献   
50.
The oxygen radical absorbance capacity (ORAC) and the ferric reducing antioxidant power (FRAP) methods were used for the determination of antioxidant capacities (AC) of rapeseed oils at different steps of technological process and olive oils. The mean ORAC and FRAP results obtained for rapeseed oils (1,106–160 and 552–95.6 μmol TE/100 g) were higher than for olive oils (949–123 and 167–32.1 μmol TE/100 g). Although, FRAP values were lower than ORAC values for all studied oils, there is a linear and significant correlation between these two analytical methods (r = 0.9665 and 0.9298, P < 0.0005) for rapeseed and olive oils, respectively). Also, total phenolic compounds in rapeseed oils and olives correlated with antioxidant capacities (correlation coefficient ranged between 0.9470 and 0.8049). The refining process of rapeseed oils decreased the total phenolics content and antioxidant capacities by about 80%.  相似文献   
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