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121.
Cutaneous melanoma is the main cause of death for skin cancer. The majority of patients with a diagnosis of melanoma have localized disease, which can be successfully treated with surgical treatment. However, the surgical approach is not curative for advanced melanoma (AM). Indeed, the management of AM is still challenging, since melanoma is the solid tumor with the highest number of mutations and cancer cells have the capacity to evade the immune system. In the past, the treatment of AM relied on chemotherapeutic agents, without showing efficacy data. Recent knowledge on melanoma pathogenesis as well as the introduction of immunotherapies, targeted therapies vaccines, small molecules, and combination therapies has revolutionized AM management, showing promising results in terms of effectiveness and safety. The aim of this review is to assess and to discuss the role of emerging therapies for AM management in order to obtain a complete overview of the currently available treatment options and future perspectives.  相似文献   
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Recently, we proposed a Good Manufacturing Practice (GMP)-compliant production process for freeze-dried mesenchymal stem cell (MSC)-secretome (lyo-secretome): after serum starvation, the cell supernatant was collected, and the secretome was concentrated by ultrafiltration and freeze-dried, obtaining a standardized ready-to-use and stable powder. In this work, we modified the type of human platelet lysate (HPL) used as an MSC culture supplement during the lyo-secretome production process: the aim was to verify whether this change had an impact on product quality and also whether this new procedure could be validated according to GMP, proving the process robustness. MSCs were cultured with two HPLs: the standard previously validated one (HPL-E) and the new one (HPL-S). From the same pool of platelets, two batches of HPL were obtained: HPL-E (by repeated freezing and thawing cycles) and HPL-S (by adding Ca-gluconate to form a clot and its subsequent mechanical wringing). Bone marrow MSCs from three donors were separately cultured with the two HPLs until the third passage and then employed to produce lyo-secretome. The following indicators were selected to evaluate the process performance: (i) the lyo-secretome quantitative composition (in lipids and proteins), (ii) the EVs size distribution, and (iii) anti-elastase and (iv) immunomodulant activity as potency tests. The new HPL supplementation for MSCs culture induced only a few minimal changes in protein/lipid content and EVs size distribution; despite this, it did not significantly influence biological activity. The donor intrinsic MSCs variability in secretome secretion instead strongly affected the quality of the finished product and could be mitigated by concentrating the final product to reach a determined protein (and lipid) concentration. In conclusion, the modification of the type of HPL in the MSCs culture during lyo-secretome production induces only minimal changes in the composition but not in the potency, and therefore, the new procedure can be validated according to GMP.  相似文献   
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Limited capacity of communication channels has brought to the attention of many researchers the analysis of control systems subject to a quantized input set. In some fundamental cases such systems can be reduced to quantized control system of type x+=x+u, where the u takes values in a set of 2m+1 integer numbers, symmetric with respect to 0. In this paper we consider these types of systems and analyse the reachable set after K steps. Our aim is to find a set of m input values such that the reachable set after K steps contains an interval of integers [−N, . . . , N] with N as large as possible. For m=2,3 and 4, we completely solve the problem and characterize the metric associated to this quantized control system.  相似文献   
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Taking into consideration that DNA damage plays an important role in carcinogenesis, the purpose of this study was to evaluate whether some radiopacifiers widely used in clinical practice are able to induce genetic damage in primary human cells in vitro. Human peripheral lymphocytes obtained from 10 healthy volunteers were exposed to barium sulphate (BaSO4), zirconium oxide (ZnO2) and bismuth oxide (Bi2O3) at final concentrations ranging from 1 to 1000 μg/mL for 1 h at 37 °C. The negative control group was treated with vehicle control (phosphate buffer solution) for 1 h at 37 °C and the positive control group was treated with hydrogen peroxide (at 100 μM) for 5 min on ice. Results were analyzed by the Friedman non-parametric test. The results pointed all compounds tested out did not induce DNA breakage in human peripheral lymphocytes as depicted by the mean tail moment and tail intensity in all concentrations tested. In summary, our results indicate that exposure to these radiopacifiers may not be a factor that increases the level of DNA lesions in human peripheral lymphocytes as detected by single cell gel (comet) assay.  相似文献   
127.
Racemic N-(8-methoxy-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-10-ylmethyl)acetamide (compound 5) was previously identified as a novel selective MT(2) antagonist fulfilling the requirements of pharmacophore and 3D QSAR models. In this study the enantiomers of 5 were separated by medium-pressure liquid chromatography and behaved as the racemate. Compound 5 was modified at the acylaminomethyl side chain and at position C8. The resulting analogues generally behaved as melatonin receptor antagonists (GTPgammaS test) with a modest degree of selectivity (up to 10-fold) for the MT(2) receptor. Changes at the amide side chain led to a decrease in binding affinity, whereas 8-acetyl and 8-methyl derivatives 12 and 11, respectively, were as potent as the 8-methoxy parent compound 5. Docking experiments with an MT(2) receptor model suggested binding modes consistent with the observed SARs and with the lack of selectivity of the enantiomers of 5.  相似文献   
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Bulletin of Engineering Geology and the Environment - This study examines plane failure analysis of rock slopes and discusses its effect on seismic actions in a non-dimensional form, incorporating...  相似文献   
129.
Given the potent antimicrobial, antiviral, and antitumor activities of many natural products, there is an increasing interest in the synthesis of new molecules based on natural compound scaffolds. Based on a 2,4-bis(3'-indolyl)imidazole skeleton, two new series of phenylthiazolylindoles and phenylthiazolyl-7-azaindoles were obtained by Hantzsch reaction between substituted phenylthioamides and the α-bromoacetyl derivatives. Some azaindole derivatives, tested at the National Cancer Institute against a panel of ~60 tumor cell lines derived from nine human cancer cell types, showed inhibitory effects against all cell lines investigated at micromolar to nanomolar concentrations. Two of them exhibited a high affinity for CDK1, with IC(50) values of 0.41 and 0.85 μM. These promising results will set the foundation for future investigations into the development of anticancer therapies.  相似文献   
130.
Heteroanalogues of angelicin, pyrrolo[3,2-h]quinazolines, were synthesized with the aim of obtaining new potent photochemotherapeutic agents. Many derivatives caused a significant decrease in cell proliferation in several human tumor cell lines after irradiation with UVA light (GI(50) =15.2-0.2 μM). Their phototoxicity effected apoptosis in Jurkat cells with the involvement of mitochondria (as determined by the loss of mitochondrial membrane potential and production of reactive oxygen species) and lysosomes. The phototoxicity of these compounds could be explained by lipid peroxidation.  相似文献   
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