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61.
Amyloids and antimicrobial peptides (AMPs) have many similarities, e.g., both kill microorganisms by destroying their membranes, form aggregates, and modulate the innate immune system. Given these similarities and the fact that the antimicrobial properties of short amyloids have not yet been investigated, we chose a group of potentially antimicrobial short amyloids to verify their impact on bacterial and eukaryotic cells. We used AmpGram, a best-performing AMP classification model, and selected ten amyloids with the highest AMP probability for our experimental research. Our results indicate that four tested amyloids: VQIVCK, VCIVYK, KCWCFT, and GGYLLG, formed aggregates under the conditions routinely used to evaluate peptide antimicrobial properties, but none of the tested amyloids exhibited antimicrobial or cytotoxic properties. Accordingly, they should be included in the negative datasets to train the next-generation AMP prediction models, based on experimentally confirmed AMP and non-AMP sequences. In the article, we also emphasize the importance of reporting non-AMPs, given that only a handful of such sequences have been officially confirmed.  相似文献   
62.
From the multitude of materials currently available on the market that can be used in the development of microparticles, sodium alginate has become one of the most studied natural anionic polymers that can be included in controlled-release pharmaceutical systems alongside other polymers due to its low cost, low toxicity, biocompatibility, biodegradability and gelatinous die-forming capacity in the presence of Ca2+ ions. In this review, we have shown that through coacervation, the particulate systems for the dispensing of drugs consisting of natural polymers are nontoxic, allowing the repeated administration of medicinal substances and the protection of better the medicinal substances from degradation, which can increase the capture capacity of the drug and extend its release from the pharmaceutical form.  相似文献   
63.
This study aimed to evaluate the safety and potential use of soy isoflavones in the treatment of skin problems, difficult-to-heal wounds and postoperative scars in women after the oncological treatment of breast cancer. The effects of different concentrations of genistein as a representative of soy isoflavonoids on MCF-7 tumor cells and BJ skin fibroblasts cultured in vitro were assessed. Genistein affects both healthy dermal BJ fibroblasts and cancerous MCF-7 cells. The effect of the tested isoflavonoid is closely related to its concentration. High concentrations of genistein destroy MCF-7 cancer cells, regardless of the exposure time, with a much greater effect on reducing cancer cell numbers at longer times (48 h). Lower concentrations of genistein (10 and 20 μM) increase the abundance of dermal fibroblasts. However, higher concentrations of genistein (50 μM and higher) are detrimental to fibroblasts at longer exposure times (48 h). Our studies indicate that although genistein shows high potential for use in the treatment of skin problems, wounds and surgical scars in women during and after breast cancer treatment, it is not completely safe. Introducing isoflavonoids to treatment requires further research into their mechanisms of action at the molecular level, taking into account genetic and immunological aspects. It is also necessary to conduct research in in vivo models, which will allow for eliminating adverse side effects of therapy.  相似文献   
64.
65.
Contributions to thermodynamic properties of the endohedral He@C60, resulting from motion of He inside the cage, are calculated. The contribution to Cv shows a maximum at low temperatures. The maxima for 3He@C60 and 4He@C60 are at about 41 K and 30 K, respectively.  相似文献   
66.
The effect of 26 staling compounds on the aged flavour of a Belgian lager beer was studied. Strikingly, thresholds were regularly found to be substantially lower than those previously reported, and it appeared important to consider threshold values as indicative rather than absolute because of very large variations in sensitivity of individuals. In addition, a masking effect of isoamyl acetate and various interactions were observed between flavour compounds, which can considerably influence their flavour activity, even at sub-threshold concentrations. Cardboard flavour was essentially caused by (E)-2-nonenal. Additionally, methional, 3-methylbutanal, 2-furfuryl ethyl ether, β-damascenone and acetaldehyde were confirmed as key contributors to the aged flavour and to a lesser extent, (E,E)-2,4-decadienal, phenylacetaldehyde, 2-methylpropanal, diacetyl and 5-hydroxymethyfurfural. Finally, the addition of a selection of compounds could fairly well reproduce the flavour of aged lager beer, indicating that these compounds account for the major part of this flavour.  相似文献   
67.
A two-level production control system based on an on-line dynamic direct coordination method is discussed. Within the structure, each local unit makes decisions keeping to the coupling outputs as recommended by the coordinator. An application to a system in process industry is given.  相似文献   
68.
69.
After reviewing the specific literature mainly on cytokines role in eosinophilic pleural chemotaxis, the study on 27 cases of eosinophilic pleurisy is presented. Only 3 cases were malignant pleurisies. The ratio between blood and pleural fluid eosinophils has no semiologic significance. Tuberculosis and parasitoses have no special significance. Autonomous eosinophilic pleurisies are regarded as a distinct nosologic entity. Their prognosis is favourable. The glucocorticoids are the choice treatment.  相似文献   
70.
The therapeutic applications of titanium-nickel (TiNi) shape memory clamps with optimized structural characteristics for fixation of small bone fragments in 64 patients are presented. Our fixative makes compressive stabilization possible and enables a patient to start rehabilitation very soon after surgery. The supporting splint immobilization never exceeded 12 days. Three aspects were studied: bone union, wound healing problems and histology. Non-union occurred in 4 patients treated with only one fixative. Two clamps implanted in non-parallel planes seem to be advisable to exclude the need for longer immobilization. Neither toxic manifestation nor episodes of an allergic reaction occurred. No suppuration appeared when a heat stimulus was supplied by using a contact resistance heater. Histological evaluation of the tissue covering the implants in 22 patients did not reveal any adverse reaction. Our study suggests that by using TiNi clamps in an appropriate way, satisfactory outcomes could be achieved with respect to both biofunctionality and biocompatibility.  相似文献   
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