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The aim of this study was to investigate dermal delivery of the new active pharmaceutical ingredient (API) TOP-N53 into diabetic foot ulcer using an in vitro wound model consisting of pig ear dermis and elucidate the impact of drug formulation and wound dressing taking into consideration clinical relevance in the home care setting and possible bacterial infection. Different formulation approaches for the poorly water-soluble API including colloidal solubilization, drug micro-suspension and cosolvent addition were investigated; moreover, the effect of (micro-)viscosity of hydrogels used as primary wound dressing on delivery was assessed. Addition of Transcutol® P as cosolvent to water improved solubility and was significantly superior to all other approaches providing a sustained three-day delivery that reached therapeutic drug levels in the tissue. Solubilization in micelles or liposomes, on the contrary, did not boost delivery while micro-suspensions exhibited sedimentation on the tissue surface. Microbial contamination was responsible for considerable metabolism of the drug leading to tissue penetration of metabolites which may be relevant for therapeutic effect. Use of hydrogels under semi-occlusive conditions significantly reduced drug delivery in a viscosity-dependent fashion. Micro-rheologic analysis of the gels using diffusive wave spectroscopy confirmed the restricted diffusion of drug particles in the gel lattice which correlated with the obtained tissue delivery results. Hence, the advantages of hydrogel dressings from the applicatory characteristic point of view must be weighed against their adverse effect on drug delivery. The employed in vitro wound model was useful for the assessment of drug delivery and the development of a drug therapy concept for chronic diabetic foot ulcer. Mechanistic insights about formulation and dressing performance may be applied to drug delivery in other skin conditions such as digital ulcer.

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Mutations in the genes encoding the highly conserved Ca2+-sensing protein calmodulin (CaM) cause severe cardiac arrhythmias, including catecholaminergic polymorphic ventricular tachycardia or long QT syndrome and sudden cardiac death. Most of the identified arrhythmogenic mutations reside in the C-terminal domain of CaM and mostly affect Ca2+-coordinating residues. One exception is the catecholaminergic polymorphic ventricular tachycardia-causing N53I substitution, which resides in the N-terminal domain (N-domain). It does not affect Ca2+ coordination and has only a minor impact on binding affinity toward Ca2+ and on other biophysical properties. Nevertheless, the N53I substitution dramatically affects CaM's ability to reduce the open probability of the cardiac ryanodine receptor (RyR2) while having no effect on the regulation of the plasmalemmal voltage-gated Ca2+ channel, Cav1.2. To gain more insight into the molecular disease mechanism of this mutant, we used NMR to investigate the structures and dynamics of both apo- and Ca2+-bound CaM-N53I in solution. We also solved the crystal structures of WT and N53I CaM in complex with the primary calmodulin-binding domain (CaMBD2) from RyR2 at 1.84-2.13 Å resolutions. We found that all structures of the arrhythmogenic CaM-N53I variant are highly similar to those of WT CaM. However, we noted that the N53I substitution exposes an additional hydrophobic surface and that the intramolecular dynamics of the protein are significantly altered such that they destabilize the CaM N-domain. We conclude that the N53I-induced changes alter the interaction of the CaM N-domain with RyR2 and thereby likely cause the arrhythmogenic phenotype of this mutation.

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BACKGROUND: Lung cancer is one of the most common malignancies around the world. The lack of early diagnosis and effective treatment strategies contributes to the poor prognosis of patients with lung cancer. Recent studies have implied the role of long non-coding RNAs (lncRNAs) in oncogenesis. The purpose of our study was to identify specific lncRNAs which were correlated with non-small cell lung cancer (NSCLC) and their potential functions. MATERIALS AND METHODS: The global plasma lncRNA profiling was performed using LncPathTM Human Cancer Array, and 11 lncRNAs were then selected for quantitative reverse transcription PCR (qRT-PCR) validation in 138 plasma samples from 69 NSCLC patients and 69 healthy controls (HCs). A noteworthy lncRNA, RP11-438N5.3, the function of which was previously unknown, was further explored on the aspect of the correlation of its expression level with clinicopathological factors. RESULTS: The results revealed that plasma level of RP11-438N5.3 was significantly lower in NSCLCs than that in HCs (p <0.01). Receiver operating characteristic (ROC) analyses showed that the area under the ROC curve (AUC) for plasma RP11-438N5.3 was 0.814 (95% CI, 0.743-0.885; p<0.01). High expression of RP11-438N5.3 in plasma correlated with favorable prognosis for NSCLC patients (Hazard ratio = 2.827; 95% CI: 1.036 to 7.718; p = 0.024; Cox regression analysis). Moreover, we found that the plasma level of stromal interaction molecule 1 (STIM1) mRNA was remarkably higher in NSCLC compared with HC (p<0.01), and the AUC for STIM1 was 0.753 (95% CI, 0.673-0.833; p<0.01), RP11-438N5.3 and STIM1 were inversely correlated with each other. CONCLUSION: Our results indicated that RP11-438N5.3 and STIM1 might provide a new strategy for NSCLC diagnosis. Furthermore, increased circulating RP11-438N5.3 level holds great potential in indicating a beneficial prognosis in NSCLC patients.

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Derivatives of the anthraquinone (anthracene-9,10-dione) such as doxorubicin, mitoxantrone and others have proved great clinical efficacy for decades. Currently the search in this exceptionally productive chemical class is aimed at optimization of antitumor properties including circumvention of drug resistance. Previously we have reported that heteroarene-fused anthraquinones fused to a 5-membered heterocyclic ring are advantageous in killing drug resistant tumor cells. Herein we present the synthesis and antitumor properties of a series of new anthra[2,3-b]furan-2-carboxamides. Vast majority of new derivatives were similarly cytotoxic to wild type tumor cell lines and their isogenic sublines with P-glycoprotein overexpression and/or p53 inactivation. Comparison of structurally close derivatives varying in their position relative to the furan moiety, that is, furan-3-carboxamide 1vs furan-2-carboxamides 5 and 6, revealed fundamental differences in the cytotoxicity profiles, formation of drug-DNA complexes, efficacy of topoisomerase 1 inhibition and mechanisms of tumor cell death. Together with previous SAR data on the role of individual substituents, these results provide evidence that regioisomerization of anthra[2,3-b]furancarboxamides generates the practically perspective derivatives whose properties may vary significantly.

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Non-steroidal anti-inflammatory drugs (NSAIDs), i.e. indomethacin used for rheumatoid arthritis and non-rheumatoid inflammatory diseases, are known for their injurious actions on the gastrointestinal (GI) tract. Mucosal damage can be avoided by using nanoscale systems composed by a combination of liposomes and biodegradable natural polymer, i.e. chitosan, for enhancing drug activity. Aim of this study was to prepare chitosan-lipid hybrid delivery systems for indomethacin dosage through a novel continuous method based on microfluidic principles. The drop-wise conventional method was also applied in order to investigate the effect of the two polymeric coverage processes on the nanostructures features and their interactions with indomethacin. Thermal-physical properties, mucoadhesiveness, drug entrapment efficiency, in vitro release behavior in simulated GI fluids and stability in stocking conditions were assayed and compared, respectively, for the uncoated and chitosan-coated nanoliposomes prepared by the two introduced methods. The prepared chitosan-lipid hybrid structures, with nanometric size, have shown high indomethacin loading (about 10%) and drug encapsulation efficiency up to 99%. TEM investigation has highlighted that the developed novel simil-microfluidic method is able to put a polymeric layer, surrounding indomethacin loaded nanoliposomes, thicker and smoother than that achievable by the drop-wise method, improving their storage stability. Finally, double pH tests have confirmed that the chitosan-lipid hybrid nanostructures have a gastro retentive behavior in simulated gastric and intestinal fluids thus can be used as delivery systems for the oral-controlled release of indomethacin. Based on the present results, the simil-microfluidic method, working with large volumes, in a rapid manner, without the use of drastic conditions and with a precise control over the covering process, seems to be the most promising method for the production of suitable indomethacin delivery system, with a great potential in industrial manufacturing.

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Chemical modifications of the anthraquinone scaffold are aimed at optimization of this exceptionally productive class of antitumor drugs. In particular, our previously reported anthra[2,3-b]furan-3-carboxamides demonstrated a high cytotoxic potency in cell culture and in vivo. In this study, we expanded our series of anthra[2,3-b]furan-3-carboxamides by modifying the key functional groups and dissected the structure-activity relationship within this chemotype. The majority of new compounds inhibited the growth of mammalian tumor cell lines at submicromolar to low micromolar concentrations. We found that 4,11-hydroxy groups as well as the carbonyl moiety in the carboxamide fragment were critical for cytotoxicity whereas the substituent at the 2-position of anthra[2,3-b]furan was not. Importantly, the new derivatives were similarly potent against wild type cells and their variants resistant to doxorubicin due to P-glycoprotein (Pgp) expression or p53 inactivation. The most cytotoxic derivatives 6 and 9 attenuated plasmid DNA relaxation by topoisomerase 1. Finally, we demonstrated that 6 and 9 at 1 µM induced intracellular oxidative stress, accumulation in G2/M phase of the cell cycle, and apoptosis in gastric carcinoma cell lines regardless of their p53 status. These results further substantiate the potential of anthra[2,3-b]furan-3-carboxamides as antitumor drug candidates.

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AIM: To analyze the histological features of changes in the brain tissue after ischemic stroke. MATERIAL AND METHODS: Brain tissue samples obtained in autopsy from 9 people died as a result of a left middle cerebral artery ischemic stroke from 3 to 7 days after admission were studied. Tissue samples were taken from 3 areas of the brain: 1) contiguous to the tissue necrotic damage site zone, 2) 5-10 cm distant from the previous one, 3) the contralateral hemisphere zone symmetrical to damage site. Samples were Nissl and hematoxylin-eosin stained. Detection of p53 protein, NSE, GFAP was performed by indirect immunoperoxidase immunohistochemistry. RESULTS: A decrease in the total number of neurons and glial elements, their spatial redistribution, change in cell structure and their functional activity was found. The changes of the artery wall and impaired regional blood flow were detected. The more intense NSE reactivity; p53-positive neurons, reduced neuron-astrocytes distance were identified in zones 2 and 3. CONCLUSION: Ischemic stroke is accompanied by severe histological changes. These changes with varying degrees of severity occur both in the areas adjacent to necrotic core, and in remote areas, and it is a substrate for neuroplasticity.

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In the late 18th century hundreds self-governing alpine communities in Northern Italy came under the direct control of centralized states (Austria and France) at different times. We exploit the timing and location of these interventions in a DD type design to investigate the effects of removing CPR institutions on biological welfare. We find a significant and persistent increase in infant mortality rates and a more modest decrease in birth rates as a result of state centralization. We provide evidence that these demographic changes reflect a critical loss of natural resource income caused by the disruption of communal institutions. Impacts are most severe in communities that have no prior experience with formal institutions.

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The review is devoted to an actual problem of cosmetics in gerontology, one of molecular aspects of skin aging. Cell renewal processes slow down with aging, and the proliferation apoptosis ratio shifts towards cell death. One of the most pivotal apoptotic markers is the transcription factor p53. p53 protein expression in the skin keratinocytes increases under the influence of ultraviolet radiation. Wherein when exposed to ultraviolet radiation mutant forms of p53 have been revealed in 70 % of keratinocytes. On the one hand, suppression of p53 expression decreases apoptosis in skin cells that slows down the process of aging. On the other hand, it promotes the development of tumors in the skin. Thus, maintaining the physiological balance of p53 expression in skin cells is important for the basic and practical cosmetic medicine in gerontology. In addition, p53 protein may be used as a functionality marker of skin cells when administered with geroprotective cosmetic means and instrumental cosmetology methods.

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