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(1) Background: Myelodysplastic neoplasms (MDSs) consist of a group of blood malignancies with a complex biological background. In this context, we investigated the role of autophagy and apoptosis in the pathogenesis and progression of MDSs. (2) Methods: To address this issue, we performed a systematic expression analysis on a total of 84 genes in patients with different types of MDSs (low/high risk of malignancy) versus healthy individuals. Furthermore, real-time quantitative PCR (qRT-PCR) was used to validate significantly upregulated or downregulated genes in a separate cohort of MDS patients and healthy controls. (3) Results: MDS patients were characterized by lower expression levels for a large series of genes involved in both processes compared to healthy individuals. Of importance, deregulation was more pronounced in patients with higher-risk MDS. Results from the qRT-PCR experiments displayed a high level of concordance with the PCR array, strengthening the relevance of our findings. (4) Conclusions: Our results indicate a clear effect of autophagy and apoptosis on MDS development, which becomes more pronounced as the disease progresses. The results from the present study are expected to assist in our understanding of the biological background of MDSs as well as in the identification of novel therapeutic targets.
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The aim of this study was to assess the patient characteristics, treatment patterns and disease outcomes in patients with psoriatic arthritis (PsA) referred to a combined Dermatology-Rheumatology (Derm-Rheum) Clinic. This was a retrospective study of patients seen in a combined Derm-Rheum Clinic (February 2018 to June 2020) in a Tertiary University Hospital. Consecutive patients with suspicious musculoskeletal symptoms or a known diagnosis of PsA referred to the Derm-Rheum Clinic were examined and followed simultaneously by experienced dermatologists and rheumatologists. Among 151 patients with psoriasis (PSO) with suspicious musculoskeletal complaints, 129 (85%) with a final diagnosis of PsA were included (56% females, mean age: 55 years, median disease duration: 14.2 years). In 62% of these patients (n = 94), PsA was diagnosed for the 1st time. At initial evaluation, 95% had peripheral arthritis, 45% nail involvement, 23% axial involvement, 12% enthesitis and 6% dactylitis with a median DAPSA and PASI scores of 20.5 and 1.6, respectively. 31% of the patients were not receiving any systemic treatment, 45% were on biologics, 29% on non-biologics and 10% on targeted synthetic agents (apremilast). At last visit (median interval time: 15 months), only 8% did not receive any systemic therapy (p < 0.001 compared to 1st visit), 62% were on biologics (p = 0.009 compared to 1st visit), 46% on non-biologics (p = 0.01 compared to 1st visit) and 10% remained on apremilast. The median DAPSA and PASI scores decreased significantly to 5.3 and 0, respectively. In conclusion, about 2/3 of patients with PSO and musculoskeletal complaints referred to a combined Derm-Rheum Clinic were diagnosed for the 1st time with PsA. During follow-up, the percentage of PsA patients on systemic therapies significantly increased with major improvement of disease activity indices. These data emphasize the value of combined Derm-Rheum Clinics for earlier referral, diagnosis, and more effective treatment of PsA patients.
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Artritis Psoriásica , Productos Biológicos , Dermatología , Psoriasis , Reumatología , Artritis Psoriásica/complicaciones , Artritis Psoriásica/diagnóstico , Artritis Psoriásica/tratamiento farmacológico , Productos Biológicos/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psoriasis/diagnóstico , Estudios RetrospectivosRESUMEN
Chemical composition of propolis depends on the plant source and thus on the geographic and climatic characteristics of the site of collection. The aim of this study was to investigate the chemical profile of Greek and Chinese propolis extracts from different regions and suggest similarities and differences between them. Untargeted ultrahigh-performance liquid chromatography coupled to hybrid quadrupole-Orbitrap mass spectrometry (UHPLC-HRMS) method was developed and 22 and 23 propolis samples from Greece and China, respectively, were analyzed. The experimental data led to the observation that there is considerable variability in terms of quality of the distinctive propolis samples. Partial least squares - discriminant analysis (PLS-DA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) models were constructed and allowed the identification of significant features for sample discrimination, adding relevant information for the identification of class-determining metabolites. Chinese samples overexpressed compounds that are characteristic of the poplar type propolis, whereas Greek samples overexpress the latter and the diterpenes characteristic of the Mediterranean propolis type.
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Metabolómica , Própolis/análisis , China , Cromatografía Líquida de Alta Presión , Grecia , Espectrometría de MasasRESUMEN
The present study aimed to investigate the metabolic profile, as well as the antioxidant and anti-ageing activities of twenty propolis samples from different regions of Greece. Chemical profiling of methanolic extracts was investigated using HPTLC and 1H-NMR techniques. Their antioxidant activity was evaluated by free radical scavenging methods (DPPH and ABTS), whereas anti-ageing properties were assessed as anti-collagenase activity. Extracts were also investigated in vitro for their ability to inhibit tyrosinase, which is responsible for the oxidation of L-DOPA to dopachrome and the production of melanin. The HPTLC and NMR analysis revealed high variability in the phytochemical profile of the methanolic extracts, with three major groups to be observed: a) Group I, consisting of samples rich in terpenoids, which present low antioxidant but high anti-tyrosinase activity, b) Group II, consisting of samples rich in flavonoids, which form a broad cluster with major similarities at the aromatic region and showed the highest anti-oxidant and anti-collagenase activities and c) Group III, consisting of samples with lower flavonoid content than the samples of Group II, which exhibited moderate antioxidant, anti-collagenase and anti-tyrosinase activities. In conclusion, this study has shown high differentiation on the chromatographic and spectroscopic metabolic profile of Greek propolis samples of different geographical origin, which is also reflected in their biological properties. Their important effects as antioxidant, anti-tyrosinase and anti-collagenase agents make propolis an important potent ingredient in the industry of food supplements and cosmeceuticals. Moreover, a correlation of a particular chemical propolis type to a specific type of biological activity will allow to prepare standardized extracts and develop food supplements and cosmeceuticals possessing the desired pharmacological properties.
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Própolis , Antioxidantes/farmacología , Cromatografía Líquida de Alta Presión , Flavonoides/análisis , Grecia , FitoquímicosRESUMEN
In the present study, we aimed to examine the antioxidant, antiaging and photoprotective properties of Greek honey samples of various botanical and geographical origin. Ethyl-acetate extracts were used and the and the total phenolic/flavonoid content and antioxidant capacity were evaluated. Honey extracts were then studied for their cytoprotective properties against UVB-induced photodamage using human immortalized keratinocytes (HaCaT) and/or reconstituted human skin tissue models. Specifically, the cytotoxicity, oxidative status, DNA damage and gene expression levels of specific matrix metalloproteinases (MMPs) were examined. Overall, the treatment of HaCaT cells with honey extracts resulted in lower levels of DNA strand breaks and attenuated the decrease in cell viability following UVB exposure. Additionally, honey extracts significantly decreased the total protein carbonyl content of the irradiated cells, however, they had no significant effect on their total antioxidant status. Finally, the extracts alleviated the UVB-induced up-regulation of MMPs-3, -7 and -9 in a model of reconstituted skin tissue. In conclusion, honey extracts exhibited significant photoprotective and antiaging properties under UVB exposure conditions and thus could be further exploited as promising agents for developing novel and naturally-based, antiaging cosmeceutical products.
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The small heat shock protein αA-crystallin is a molecular chaperone important for the optical properties of the vertebrate eye lens. It forms heterogeneous oligomeric ensembles. We determined the structures of human αA-crystallin oligomers by combining cryo-electron microscopy, cross-linking/mass spectrometry, NMR spectroscopy and molecular modeling. The different oligomers can be interconverted by the addition or subtraction of tetramers, leading to mainly 12-, 16- and 20-meric assemblies in which interactions between N-terminal regions are important. Cross-dimer domain-swapping of the C-terminal region is a determinant of αA-crystallin heterogeneity. Human αA-crystallin contains two cysteines, which can form an intramolecular disulfide in vivo. Oxidation in vitro requires conformational changes and oligomer dissociation. The oxidized oligomers, which are larger than reduced αA-crystallin and destabilized against unfolding, are active chaperones and can transfer the disulfide to destabilized substrate proteins. The insight into the structure and function of αA-crystallin provides a basis for understanding its role in the eye lens.
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Cadena A de alfa-Cristalina/química , Microscopía por Crioelectrón , Humanos , Cristalino/química , Modelos Moleculares , Oxidación-Reducción , Conformación Proteica , Multimerización de Proteína , Desplegamiento Proteico , Cadena A de alfa-Cristalina/ultraestructuraRESUMEN
Gender is not accurately captured by the traditional male and female dichotomy of sex. Instead, it is a complex social system that structures the life experience of all human beings. This paper, the first in a Series of five papers, investigates the relationships between gender inequality, restrictive gender norms, and health and wellbeing. Building upon past work, we offer a consolidated conceptual framework that shows how individuals born biologically male or female develop into gendered beings, and how sexism and patriarchy intersect with other forms of discrimination, such as racism, classism, and homophobia, to structure pathways to poor health. We discuss the ample evidence showing the far-reaching consequences of these pathways, including how gender inequality and restrictive gender norms impact health through differential exposures, health-related behaviours and access to care, as well as how gender-biased health research and health-care systems reinforce and reproduce gender inequalities, with serious implications for health. The cumulative consequences of structured disadvantage, mediated through discriminatory laws, policies, and institutions, as well as diet, stress, substance use, and environmental toxins, have triggered important discussions about the role of social injustice in the creation and maintenance of health inequities, especially along racial and socioeconomic lines. This Series paper raises the parallel question of whether discrimination based on gender likewise becomes embodied, with negative consequences for health. For decades, advocates have worked to eliminate gender discrimination in global health, with only modest success. A new plan and new political commitment are needed if these global health aspirations and the wider Sustainable Development Goals of the UN are to be achieved.
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Atención a la Salud , Sexismo , Factores Socioeconómicos , Femenino , Humanos , MasculinoRESUMEN
The aim of this study was to assess the antioxidant, photoprotective, and antiaging effects of Greek propolis. Propolis was subjected to n-heptane or methanol extraction. Total phenolic/flavonoid content and antioxidant potential were determined in the extracts. Promising extracts were evaluated for their cytoprotective properties using human immortalized keratinocyte (HaCaT) or reconstituted human skin tissue following exposure to UVB. Assessment of cytotoxicity, DNA damage, oxidative status, and gene/protein expression levels of various matrix metalloproteinases (MMPs) were performed. The propolis methanolic fractions exhibited higher total phenolic and flavonoid contents and significant in vitro antioxidant activity. Incubation of HaCaT cells with certain methanolic extracts significantly decreased the formation of DNA strand breaks following exposure to UVB and attenuated UVB-induced decrease in cell viability. The extracts had no remarkable effect on the total antioxidant status, but significantly lowered total protein carbonyl content used as a marker for protein oxidation in HaCaT cells. MMP-1, -3, -7, and -9, monitored as endpoints of antiaging efficacy, were significantly reduced by propolis following UVB exposure in a model of reconstituted skin tissue. In conclusion, propolis protects against the oxidative and photodamaging effects of UVB and could be further explored as a promising agent for developing natural antiaging strategies.
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NMR spectroscopy at ultra-high magnetic fields requires improved radiofrequency (rf) pulses to cover the increased spectral bandwidth. Optimized 90° pulse pairs were introduced as Ramsey-type cooperative (Ram-COOP) pulses for biomolecular NMR applications. The Ram-COOP element provides broadband excitation with enhanced sensitivity and reduced artifacts even at magnetic fields >1.0â GHz 1 H Larmor frequency (23â T). A pair of 30â µs Ram-COOP pulses achieves an excitation bandwidth of 100â kHz with a maximum rf field of 20â kHz, more than three-fold improved compared to excitation by rectangular pulses. Ram-COOP pulses exhibit little offset-dependent phase errors and are robust to rf inhomogeneity. The performance of the Ram-COOP element is experimentally confirmed with heteronuclear multidimensional NMR experiments, applied to proteins and nucleic acids. Ram-COOP provides broadband excitation at low rf field strength suitable for application at current magnetic fields and beyond 23â T.
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Resonancia Magnética Nuclear Biomolecular/métodos , Algoritmos , Artefactos , Simulación por ComputadorRESUMEN
In a study of 62 plant species of the Cretan flora for their phytotoxic activity, plants were extracted successively with CH2Cl2, MeOH and H2O. Phytotoxicity evaluation of the 240 extracts was performed against Lactuca sativa L. and Agrostis stolonifera L.. The MeOH extract of Bellis longifolia was the most phytotoxic. Bioassay-guided fractionation revealed that a fraction consisting mainly of saponins was the most effective. Separation of the saponins was performed using initially a step-gradient Centrifugal Partition Chromatography (CPC). Investigation of the active fraction led to the isolation and structure elucidation of three previously undescribed triterpene saponins, 3-O-ß-D-fucopyranosyl polygalacic acid, 28-O-α-L-rhamnopyranosyl-(1 â 2)-ß-D-fucopyranosyl polygalacic acid and 3-O-ß-D-fucopyranosyl-2α,3ß,23-trihydroxyolean-12-en-28-oic acid, which were present as the main phytotoxic compounds of the methanol extract. Two triterpenes, polygalacic acid and bellisonic acid and four kaempferol glucosides, as well as chlorogenic acid were also isolated. 3-O-ß-D-fucopyranosyl polygalacic acid and 3-O-ß-D-fucopyranosyl-2α,3ß,23-trihydroxyolean-12-en-28-oic acid had phytotoxic activity similar to some commercial herbicides (IC50 values of ca. 25 µM) against duckweed (Lemna paucicostata).
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Araceae/efectos de los fármacos , Asteraceae/química , Herbicidas/farmacología , Saponinas/farmacología , Triterpenos/farmacología , Relación Dosis-Respuesta a Droga , Herbicidas/química , Herbicidas/aislamiento & purificación , Conformación Molecular , Saponinas/química , Saponinas/aislamiento & purificación , Triterpenos/química , Triterpenos/aislamiento & purificaciónRESUMEN
Ketolides belong to the latest generation of macrolides and are not only effective against macrolide susceptible bacterial strains but also against some macrolide resistant strains. Here we present data providing insights into the mechanism of action of K-1602, a novel alkyl-aryl-bearing fluoroketolide. According to our data, the K-1602 interacts with the ribosome as a one-step slow binding inhibitor, displaying an association rate constant equal to 0.28 × 10(4) M(-1) s(-1) and a dissociation rate constant equal to 0.0025 min(-1). Both constants contribute to produce an overall inhibition constant Ki equal to 1.49 × 10(-8) M, which correlates very well with the superior activity of this compound when compared with many other ketolides or fluoroketolides.
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Cetólidos/química , Cetólidos/farmacología , Ribosomas/efectos de los fármacos , Unión Competitiva , Farmacorresistencia Bacteriana/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Cinética , Puromicina/química , Proteínas Ribosómicas/química , Proteínas Ribosómicas/metabolismo , Tilosina/química , Tilosina/farmacologíaRESUMEN
Small heat-shock proteins, including αB-crystallin (αB), play an important part in protein homeostasis, because their ATP-independent chaperone activity inhibits uncontrolled protein aggregation. Mechanistic details of human αB, particularly in its client-bound state, have been elusive so far, owing to the high molecular weight and the heterogeneity of these complexes. Here we provide structural insights into this highly dynamic assembly and show, by using state-of-the-art NMR spectroscopy, that the αB complex is assembled from asymmetric building blocks. Interaction studies demonstrated that the fibril-forming Alzheimer's disease Aß1-40 peptide preferentially binds to a hydrophobic edge of the central ß-sandwich of αB. In contrast, the amorphously aggregating client lysozyme is captured by the partially disordered N-terminal domain of αB. We suggest that αB uses its inherent structural plasticity to expose distinct binding interfaces and thus interact with a wide range of structurally variable clients.