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71.
Afzan A. Ayoub Abdel H. Mahmoud Juliana S. Ribeiro Arwa Daghrery Jinping Xu J. Christopher Fenno Anna Schwendeman Hajime Sasaki Renan Dal-Fabbro Marco C. Bottino 《International journal of molecular sciences》2022,23(22)
This study was aimed at engineering photocrosslinkable azithromycin (AZ)-laden gelatin methacryloyl fibers via electrospinning to serve as a localized and biodegradable drug delivery system for endodontic infection control. AZ at three distinct amounts was mixed with solubilized gelatin methacryloyl and the photoinitiator to obtain the following fibers: GelMA+5%AZ, GelMA+10%AZ, and GelMA+15%AZ. Fiber morphology, diameter, AZ incorporation, mechanical properties, degradation profile, and antimicrobial action against Aggregatibacter actinomycetemcomitans and Actinomyces naeslundii were also studied. In vitro compatibility with human-derived dental pulp stem cells and inflammatory response in vivo using a subcutaneous rat model were also determined. A bead-free fibrous microstructure with interconnected pores was observed for all groups. GelMA and GelMA+10%AZ had the highest fiber diameter means. The tensile strength of the GelMA-based fibers was reduced upon AZ addition. A similar pattern was observed for the degradation profile in vitro. GelMA+15%AZ fibers led to the highest bacterial inhibition. The presence of AZ, regardless of the concentration, did not pose significant toxicity. In vivo findings indicated higher blood vessel formation, mild inflammation, and mature and thick well-oriented collagen fibers interweaving with the engineered fibers. Altogether, AZ-laden photocrosslinkable GelMA fibers had adequate mechanical and degradation properties, with 15%AZ displaying significant antimicrobial activity without compromising biocompatibility. 相似文献
72.
Israa M. Shamkh Mohammed Al-Majidi Ahmed Hassen Shntaif Peter Tan Deng Kai Ngoc Nh-Pham Ishrat Rahman Dalia Hamza Mohammad Shahbaz Khan Maii S. Elsharayidi Eman T. Salah Abdullah Haikal Modupe Akintomiwa Omoniyi Mahmoud A. Abdalrahman Tomasz M. Karpinski 《International journal of molecular sciences》2022,23(21)
In recent years, novel strategies to control insects have been based on protease inhibitors (PIs). In this regard, molecular docking and molecular dynamics simulations have been extensively used to investigate insect gut proteases and the interactions of PIs for the development of resistance against insects. We, herein, report an in silico study of (disodium 5′-inosinate and petunidin 3-glucoside), (calcium 5′-guanylate and chlorogenic acid), chlorogenic acid alone, (kaempferol-3,7-di-O-glucoside with hyperoside and delphinidin 3-glucoside), and (myricetin 3′-glucoside and hyperoside) as potential inhibitors of acetylcholinesterase receptors, actin, α-tubulin, arginine kinase, and histone receptor III subtypes, respectively. The study demonstrated that the inhibitors are capable of forming stable complexes with the corresponding proteins while also showing great potential for inhibitory activity in the proposed protein-inhibitor combinations. 相似文献
73.
Steven J. Fliesler Sriganesh Ramachandra Rao Mai N. Nguyen Mahmoud Tawfik KhalafAllah Steven J. Pittler 《International journal of molecular sciences》2022,23(21)
Retinitis pigmentosa-59 (RP59) is a rare, recessive form of RP, caused by mutations in the gene encoding DHDDS (dehydrodolichyl diphosphate synthase). DHDDS forms a heterotetrameric complex with Nogo-B receptor (NgBR; gene NUS1) to form a cis-prenyltransferase (CPT) enzyme complex, which is required for the synthesis of dolichol, which in turn is required for protein N-glycosylation as well as other glycosylation reactions in eukaryotic cells. Herein, we review the published phenotypic characteristics of RP59 models extant, with an emphasis on their ocular phenotypes, based primarily upon knock-in of known RP59-associated DHDDS mutations as well as cell type- and tissue-specific knockout of DHDDS alleles in mice. We also briefly review findings in RP59 patients with retinal disease and other patients with DHDDS mutations causing epilepsy and other neurologic disease. We discuss these findings in the context of addressing “knowledge gaps” in our current understanding of the underlying pathobiology mechanism of RP59, as well as their potential utility for developing therapeutic interventions to block the onset or to dampen the severity or progression of RP59. 相似文献
74.
Pter P. Lakatos Dvid rpd Kardi Anna Rita Galambos Nariman Essmat Kornl Kirly Rudolf Laufer Orsolya Geda Zoltn S. Zdori Tams Tbi Mahmoud Al-Khrasani va Szk 《International journal of molecular sciences》2022,23(17)
Current treatment approaches to manage neuropathic pain have a slow onset and their use is largely hampered by side-effects, thus there is a significant need for finding new medications. Tolperisone, a centrally acting muscle relaxant with a favorable side effect profile, has been reported to affect ion channels, which are targets for current first-line medications in neuropathic pain. Our aim was to explore its antinociceptive potency in rats developing neuropathic pain evoked by partial sciatic nerve ligation and the mechanisms involved. Acute oral tolperisone restores both the decreased paw pressure threshold and the elevated glutamate level in cerebrospinal fluid in neuropathic rats. These effects were comparable to those of pregabalin, a first-line medication in neuropathy. Tolperisone also inhibits release of glutamate from rat brain synaptosomes primarily by blockade of voltage-dependent sodium channels, although inhibition of calcium channels may also be involved at higher concentrations. However, pregabalin fails to affect glutamate release under our present conditions, indicating a different mechanism of action. These results lay the foundation of the avenue for repurposing tolperisone as an analgesic drug to relieve neuropathic pain. 相似文献
75.
Transmission pricing has become a major issue in the discussions about the deregulated electricity markets.Consequently,open access to the transmission system is one of the basic topics to allow competition among participants in the energy market.Transmission costs have an important impact on relative competition among participants in the energy market as well as on short-and long-term economic efficiencies of the whole electricity industry,although they represent only close to 10% of the energy market price.This paper deals with the design and tests of a transmission pricing method based on the optimal circuit prices derived from the economically adapted network(EAN).Prices derived from the EAN have the advantage of being in tune with the maximum revenue allowed to the owner of transmission assets and simplifying the optimal allocation of transmission costs among participants.Beginning from the conceptual design,the proposed method is tested on a three-bus network and on the IEEE 24-bus reliability test system. 相似文献
76.
András Faragó 《Algorithmica》2007,49(4):337-356
We prove two results that provide new fundamental limits for topology control in large ad hoc and sensor networks. First,
we show that it remains true under very general conditions that the maximum expected node degree must grow to infinity at
least logarithmically if we want to maintain asymptotic connectivity. This has been known so far only for much more special
models than ours. Building on this result, we prove a new fundamental limit regarding link dynamics, which means the worst case length ratio of the longest and shortest link adjacent to the same node. We prove that if link
dynamics remains bounded, then no topology control algorithm can keep a large network connected with high probability. Moreover,
bounded link dynamics prevents connectivity in the limit without any a priori assumption on node degrees or transmission ranges.
Our results hold in a model that is much more general than the frequently used assumption of uniformly distributed nodes in
a regularly shaped planar domain. Our more abstract setting also aims at finding (hopefully) more robust and elegant proofs
that have less dependence on the special geometry. Since link dynamics is expected to be bounded in practice, the results
strenghten the theoretical basis for the argument that a very large ad hoc or sensor network is unable to maintain connectivity
if it has a flat, random organization without additional structure.
Supported in part by NSF Grants ANI-0220001 and CCF-0634848. 相似文献
77.
Omar Mahmoud Georgia Biazus Soares Gil Yosipovitch 《International journal of molecular sciences》2023,24(1)
Transient Receptor Potential (TRP) channels are multifunctional sensory molecules that are abundant in the skin and are involved in the sensory pathways of itch, pain, and inflammation. In this review article, we explore the complex physiology of different TRP channels, their role in modulating itch sensation, and their contributions to the pathophysiology of acute and chronic itch conditions. We also cover small molecule and topical TRP channel agents that are emerging as potential anti-pruritic treatments; some of which have shown great promise, with a few treatments advancing into clinical trials—namely, TRPV1, TRPV3, TRPA1, and TRPM8 targets. Lastly, we touch on possible ethnic differences in TRP channel genetic polymorphisms and how this may affect treatment response to TRP channel targets. Further controlled studies on the safety and efficacy of these emerging treatments is needed before clinical use. 相似文献
78.
Several recent foodborne disease outbreaks associated with leafy green vegetables, including spinach, have been reported. X-ray is a non-thermal technology that has shown promise for reducing pathogenic and spoilage bacteria on spinach leaves. Inactivation of inoculated Escherichia coli O157:H7, Listeria monocytogenes, Salmonella enterica and Shigella flexneri on spinach leaves using X-ray at different doses (0.1, 0.2, 0.3, 0.5, 0.75, 1.0, 1.5 and 2.0 kGy) was studied. The effect of X-ray on color quality and microflora counts (mesophilic counts, psychrotrophic counts and yeast and mold counts) of untreated and treated spinach was also determined. A mixture of three strains of each tested organism was spot inoculated (100 μl) onto the surface of spinach leaves (approximately 8–9 log ml−1), separately, and air-dried, followed by treatment with X-ray at 22 °C and 55–60% relative humidity. Surviving bacterial populations on spinach leaves were evaluated using a nonselective medium (tryptic soy agar) with a selective medium overlay for each bacteria; E. coli O157:H7 (CT-SMAC agar), L. monocytogenes (MOA), and S. enterica and S. flexneri (XLD). More than a 5 log CFU reduction/leaf was achieved with 2.0 kGy X-ray for all tested pathogens. Furthermore, treatment with X-ray significantly reduced the initial inherent microflora on spinach leaves and inherent levels were significantly (p < 0.05) lower than the control sample throughout refrigerated storage for 30 days. Treatment with X-ray did not significantly affect the color of spinach leaves, even when the maximum dose (2.0 kGy) was used. 相似文献
79.
Adel AA Mohdaly Mohamed A Sarhan Iryna Smetanska Awad Mahmoud 《Journal of the science of food and agriculture》2010,90(2):218-226
BACKGROUND: Growing interest in the replacement of synthetic food antioxidants by natural ones has fostered research on vegetable sources and screening of raw materials to identify new antioxidants. The food‐processing industry generates substantial quantities of phenolic‐rich by‐products that could be valuable natural sources of antioxidants. In this study the antioxidant properties and total phenolic, flavonoid and flavonol contents of three industrial by‐products, sugar beet pulp, sesame cake and potato peel, extracted with various solvents were examined. Since different antioxidant compounds have different mechanisms of action, several methods were used to assess the antioxidant efficacy of extracts. RESULTS: Among the six solvents tested, methanol gave the highest extract yield of potato peel and sugar beet pulp, while diethyl ether gave the highest extract yield of sesame cake. Methanol exhibited the highest extraction ability for phenolic compounds, with total phenolics amounting to 2.91, 1.79 and 0.81 mg gallic acid equivalent g?1 dry weight in potato peel, sugar beet pulp and sesame cake extracts respectively, and also showed the strongest antioxidant capacity in the three assays used. All three methods proved that potato peel extract had the highest antioxidant activity owing to its high content of phenolic compounds and flavonoids. CONCLUSION: On the basis of the results obtained, potato peel, sugar beet pulp and sesame cake extracts could serve as natural antioxidants owing to their significant antioxidant activity. Therefore they could be used as preservative ingredients in the food and/or pharmaceutical industries. Copyright © 2009 Society of Chemical Industry 相似文献
80.
Although the wind farms based on squirrel cage induction generators (SCIG) is cheaper than the wind farms based on doubly fed induction generators (DFIG), it is always in desperate need for reactive power compensation. Nevertheless, the wind farms based on DFIG are expensive compared with the SCIG wind farm, it features by its ability to control the active power independent of reactive power. However, combined wind farm (CWF) has been developed to collect the benefits of SCIG and DFIG wind turbines in the same wind farm. In this article, artificial neural network (ANN) is used to evaluate gain parameters of static synchronous compensator (STATCOM) in order to improve the stability performance of CWF. The impact of tuned STATCOM on the performance of CWF during gust wind speed and during three-phase fault is comprehensively investigated. The performance of CWF with STATCOM tuned by ANN is compared with its performance when the STATCOM tuned by the multiobjective genetic algorithm (MOGA) and whale optimization algorithm (WOA). The results show that the performance of CWF can be enhanced using STATCOM tuned by ANN more than MOGA and WOA. 相似文献