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The activity of granulocyte elastase (GE) was discovered in the preparations of leukocyte thermostable alpha-glycoprotein (LTG) isolated from pus by means of ion-exchange chromatography. The activity of GE was determined according to MeoSuc(Ala)2ProValpNa hydrolysis. The antibodies against LTG were isolated from monospecific antisera. Sepharose with immobilized fraction of pus proteins was utilized as immunosorbent. Isolated antibodies to LTG inhibited the GE activity. An inhibitory effect of antibodies increased with the increase in their concentration. The identity or binding of LTG and GE was suggested. The binding of LTG with pus protein component was discovered, the biological meaning of this phenomenon being unknown.  相似文献   
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There was performed a comparative analysis of phospholipids and of lipid physicochemical characteristics in spleen, blood erythrocytes, and liver of the root voles caught in the natural environmental habitation at different phases of the population cycle, as well of the animals born and raised throughout the entire live in vivarium, depending on the animals’ sex and age. The age-related changes in the phospholipid composition have been established to correlate with lipid physicochemical characteristics, while the scale and direction of the changes depend on the tissue functional role, the initial level of the antioxidative activity (AOA) of its lipids, and sex of the animals. In the process of the organism aging, parameters of the system of regulation of lipid peroxidation change not unidirectionally; in group of animals of the same age, individuals with different biochemical characteristics can be present. Under natural conditions of habitation the degree of expression of age-related changes is modified by populational factors.  相似文献   
664.
Proteomics research infrastructures and core facilities within the Core for Life alliance advocate for community policies for quality control to ensure high standards in proteomics services.

Core facilities and research infrastructures have become an essential part of the scientific ecosystem. In the field of proteomics, national and international networks and research platforms have been established during the past decade that are supposed to set standards for high‐quality services, promote an exchange of professional information, and enable access to cutting‐edge, specialized proteomics technologies. Either centralized or distributed, these national and international proteomics infrastructures and technology platforms are generating massive amounts of data for the research community, and support a broad range of translational, computational and multi‐omics initiatives and basic research projects.By delegating part of their work to these services, researchers expect that the core facility adjusts their analytical protocols appropriately for their project to acquire data conforming best research practice of the scientific community. The implementation of quality assessment measures and commonly accepted quality controls in data generation is therefore crucially important for proteomics research infrastructures and the scientists who rely on them.However, current quality control and quality assessment procedures in proteomics core facilities and research infrastructures are a motley collection of protocols, standards, reference compounds and software tools. Proteomics relies on a customized multi‐step workflow typically consisting of sample preparation, data acquisition and data processing, and the implementation of each step differs among facilities. For example, sample preparation involves enzymatic digestion of the proteins, which can be performed in‐solution, in‐gel, or on‐beads, with often different proteolytic enzymes, chemicals, and conditions among laboratories. Data acquisition protocols are often customized to the particular instrument set up, and the acquired spectra and chromatograms are processed by different software tools provided by equipment vendors, third parties or developed in‐house.
…current quality control and quality assessment procedures in proteomics core facilities and research infrastructures are a motley collection of protocols, standards, reference compounds and software tools.
Moreover, core facilities implement their own guidelines to monitor the performance and quality of the entire workflow, typically utilizing different commercially available standards such as pre‐digested cell lysates, recombinant proteins, protein mixtures, or isotopically labeled peptides. Currently, there is no clear consensus on if, when and how to perform quality control checks. There is even less quality control in walk‐in facilities, where the staff is only responsible for correct usage of the instruments and users select and execute the analytical workflow themselves. It is not surprising therefore that instrument stability and robustness of the applied analytical approach are often unclear, which compromises analytical rigor.  相似文献   
665.
This study was designed to examine in vivo functional changes of the heart in the early stages of streptozotocin (STZ)-induced diabetic cardiomyopathy and to evaluate the effects of n-3 PUFA intake. Moreover, we investigated whether modulation of diabetes-related abnormalities of myocardial connexin-43 (Cx43), β-myosin heavy chain (β-MHC), and β1-adrenergic receptors (β1-AR) might be implicated in the cardioprotective mechanism of n-3 PUFA. Our results showed significantly reduced cardiac output and ejection fraction (using the microtip pressure–volume catheter technique) as well as stroke volume and stroke work, 4 weeks after STZ-induced diabetes, with improvement of these parameters due to n-3 PUFA consumption. Myocardial expression of Cx43 mRNA estimated by real-time polymerase chain reaction did not change in diabetic rats regardless of n-3 PUFA consumption (100 mg/100 g b.w./day). In contrast, the total and functional phosphorylated form of Cx43 protein increased significantly, and its cardiomyocyte-related distribution was disordered in the diabetic heart, but these changes normalized because of n-3 PUFA intake. Furthermore, acute diabetes was accompanied by decrease of myocardial β1-AR mRNA expression and mild yet nonsignificant increase of β-MHC mRNA. These alterations were not significantly affected by n-3 PUFA. In conclusion, the results point out that STZ-diabetic rats benefit from n-3 PUFA consumption particularly because of the attenuation of myocardial Cx43 abnormalities that most likely contributes to improvement of cardiac function.  相似文献   
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AECR mutants of Bacillus subtilis were obtained and analyzed. The mutants were characterized by derepression of aspartokinase II and diaminopimelate decarboxylase synthesis and the synthesis of the precursor of lysine--DAP. According to genetic mapping data, aec mutations are localized in some B. subtilis chromosomal regions; they are linked to the thr5, leuA8, lys21 markers.  相似文献   
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