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41.
The human G-leukocyte antigen (HLA-G) molecule is a non-classical major histocompatibility complex (MHC) class I molecule. The pertinence of HLA-G has been investigated in numerous studies which have sought to elucidate the relevance of HLA-G in pathologic conditions, such as autoimmune diseases, cancers, and hematologic malignancies. One of the main goals of the current research on HLA-G is to use this molecule in clinical practice, either in diagnostics or as a therapeutic target. Since HLA-G antigens are currently considered as immunomodulatory molecules that are involved in reducing inflammatory and immune responses, in this review, we decided to focus on this group of antigens as potential determinants of progression in autoimmune diseases. This article highlights what we consider as recent pivotal findings on the immunomodulatory function of HLA-G, not only to establish the role of HLA-G in the human body, but also to explain how these proteins mediate the immune response.  相似文献   
42.
Protein glycosylation requires dolichyl phosphate as a carbohydrate carrier. Dolichols are α-saturated polyprenols, and their saturation in S. cerevisiae is catalyzed by polyprenyl reductase Dfg10 together with some other unknown enzymes. The aim of this study was to identify such enzymes in Candida. The Dfg10 polyprenyl reductase from S. cerevisiae comprises a C-terminal 3-oxo-5-alpha-steroid 4-dehydrogenase domain. Alignment analysis revealed such a domain in two ORFs (orf19.209 and orf19.3293) from C. albicans, which were similar, respectively, to Dfg10 polyprenyl reductase and Tsc13 enoyl-transferase from S. cerevisiae. Deletion of orf19.209 in Candida impaired saturation of polyprenols. The Tsc13 homologue turned out not to be capable of saturating polyprenols, but limiting its expression reduce the cellular level of dolichols and polyprenols. This reduction was not due to a decreased expression of genes encoding cis-prenyltransferases from the dolichol branch but to a lower expression of genes encoding enzymes of the early stages of the mevalonate pathway. Despite the resulting lower consumption of acetyl-CoA, the sole precursor of the mevalonate pathway, it was not redirected towards fatty acid synthesis or elongation. Lowering the expression of TSC13 decreased the expression of the ACC1 gene encoding acetyl-CoA carboxylase, the key regulatory enzyme of fatty acid synthesis and elongation.  相似文献   
43.
The main aim of this work was to test the developed system of a free hand sonographic probe in the clinical conditions. The measuring system consists of navigation system tracking the position of a linear ultrasound probe and the self-developed software to control the tools and analyse the recorded data. It enables both measurement of geometrical parameters according to the self-designed template and the identification of the three dimensional shape of bone. Moreover the software provides virtual planning of surgery and supports the surgeon to execute the planned scenario in the reality.  相似文献   
44.
Even several thousands of DNA lesions are induced in one cell within one day. DNA damage may lead to mutations, formation of chromosomal aberrations, or cellular death. A particularly cytotoxic type of DNA damage is single- and double-strand breaks (SSBs and DSBs, respectively). In this work, we followed DNA conformational transitions induced by the disruption of DNA backbone. Conformational changes of chromatin in living cells were induced by a bleomycin (BLM), an anticancer drug, which generates SSBs and DSBs. Raman micro-spectroscopy enabled to observe chemical changes at the level of single cell and to collect hyperspectral images of molecular structure and composition with sub-micrometer resolution. We applied multivariate data analysis methods to extract key information from registered data, particularly to probe DNA conformational changes. Applied methodology enabled to track conformational transition from B-DNA to A-DNA upon cellular response to BLM treatment. Additionally, increased expression of proteins within the cell nucleus resulting from the activation of repair processes was demonstrated. The ongoing DNA repair process under the BLM action was also confirmed with confocal laser scanning fluorescent microscopy.  相似文献   
45.
46.
This study concerns the physicochemical and sensory analysis of stirred kefirs made at a laboratory scale, in which one‐third of the skim milk powder (SMP) was replaced by different inulins (long chain, native and oligofructose). The reference kefirs contained 12 g/100 g of SMP or whole milk powder. Rheological analysis showed that the kefirs were viscoelastic materials with thixotropic and shear‐thinning behaviour. Rheological data showed that SMP can be successfully substituted by long‐chain inulin; however, sensory evaluation indicated that substitution of SMP by any other kinds of inulin significantly decreased the consistency of kefirs while not affecting their flavour and odour.  相似文献   
47.
Inflammation is a protective reaction of the innate immune system as a response to imbalances caused by a specific stimulus, a disease or a pathogen. A prolonged inflammatory condition may lead to the development of metabolic syndrome, which affects more than one-fourth of the world’s population. This condition leads to the development of multi-organ disorders based on disrupted blood lipid and sugar levels, hypertension and oxidative stress. The review aims to present Zingiber officinale Rosc. as a plant that exhibits a variety of healing properties and restores the organism’s equilibrium. Ginger (GI) rhizomes have been commonly used in traditional medicine to treat arthritis, stomach ache, nonalcoholic fatty liver disease, rheumatism, nervous system syndromes, asthma, diabetes and nausea caused by pregnancy or chemotherapy. This review gathers together data from in vivo experiments related to the application of ginger for the treatment of inflammatory conditions, obesity, diabetes and other related disorders as a consequence of metabolic syndrome, including the confirmed molecular mechanisms of action.  相似文献   
48.
Atherosclerosis, the underlying cause of coronary artery disease (CAD), has a significant inflammatory component. White blood cell count is an affordable and accessible way to assess the systemic immune response, as it comprises many subgroups with distinct and complex functions. Considering their multidirectional effect on atherosclerosis, new biomarkers integrating various leukocyte subgroups, the Systemic Inflammatory Index (SII) and the Systemic Inflammatory Response Index (SIRI), were recently devised to describe the balance between inflammation and immune reaction. This research aimed to evaluate the relationship of the intensity of inflammation measured by these biomarkers with the severity of CAD assessed with coronary angiography and with the diagnosis of acute coronary syndrome (ACS) or stable CAD in 699 patients. SIRI, but not SII, was associated with the diagnosis, having the highest values for patients with ACS (STEMI), significantly higher than in patients with stable CAD (p < 0.01). The highest SII and SIRI values were observed in patients with three-vessel CAD. SII and SIRI require further in-depth and well-designed research to evaluate their potential in a clinical setting.  相似文献   
49.
The use of methylmalonyl‐CoA epimerase (MCEE) to improve stereoselectivity in crotonase‐mediated biocatalysis is exemplified by the coupling of MCEE, crotonyl‐CoA carboxylase reductase and carboxymethylproline synthase in a three‐enzyme one‐pot sequential synthesis of functionalised C‐5 carboxyalkylprolines starting from crotonyl‐CoA and carbon dioxide.  相似文献   
50.
BACKGROUND: Sweet red bell pepper is one of the best sources of ascorbic acid and carotenoids as well as phenolic compounds important in the human diet. There have been some studies showing a higher level of bioactive compounds in organic bell pepper fruits compared with conventional fruits, but not all studies have been consistent in this respect. The levels of carotenoids and phenolics are very variable and may be affected by ripeness, genotype and cultivation. RESULTS: The results obtained in this study showed that an organic growing system affected the level of bioactive compounds (carotenoids and polyphenols) in sweet bell pepper fruits cultivated in Poland. Organic bell pepper fruits contained significantly more dry matter, vitamin C, total carotenoids, β‐carotene, α‐carotene, cis‐β‐carotene, total phenolic acids (as well as individual gallic and chlorogenic acids) and flavonoids (quercetin D ‐glucoside, quercetin and kaempferol) compared with conventional fruits. The bell pepper variety also affected the level of antioxidant compounds in fruits. CONCLUSION: Organic growing increased the level of antioxidant compounds such as carotenoids, phenolic compounds and vitamin C in sweet bell pepper. The second significant factor affecting the antioxidant compound content of sweet bell pepper was variety. It would be necessary to continue this study as a long‐term experiment in order to eliminate the influence of seasonality. Copyright © 2012 Society of Chemical Industry  相似文献   
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