83 research outputs found
Heat-shock pretreatment inhibits sorbitol-induced apoptosis in K562, U937 and HeLa cells.
The aim of this study was to determine whether heat-shock pretreatment
exerted a protective effect against sorbitol-induced apoptotic
cell death in K562, U937 and HeLa cell lines and whether
such protection was associated with a decreased cytochrome c
release from mithocondria and a decreased activation of caspase-9
and -3. Following heat-shock pretreatment (42 6 0.3C for 1 hr),
these cell lines were exposed to sorbitol for 1 hr. Apoptosis was evaluated
by DNA fragmentation, whereas caspase-9,-3 activation, cytochrome
c release and heat-shock protein70 (HSP70) were assayed
by Western Blot. Sorbitol exposure-induced apoptosis in these different
cell lines with a marked activation of caspase-9 and caspase-
3, whereas heat-shock pretreatment before sorbitol exposure,
induced expression of HSP70 and inhibited sorbitol-mediated cytochrome
c release and subsequent activation of caspase-9 and caspase-
3. Similarly, overexpression of HSP70 in the three cell lines
studied prevented caspase-9 cleavage and activation as well as cell
death. Furthermore, we showed that the mRNA expression of iNOS
decreased during both the heat-shock treatment and heat-shock
pretreatment before sorbitol exposure. By contrast, the expression
of Cu-Zn superoxide dismutase (SOD) and Mn-SOD proteins
increased during heat-shock pretreatment before sorbitol exposure.
We conclude that, heat-shock pretreatment protects different cell
lines against sorbitol-induced apoptosis through a mechanism that
is likely to involve SOD family members
Motivational justifications of the study routine of medical students:pre and post pandemic by COVID-19
Іконографічні особливості образу Богородиці в східній християнській традиції: релігієзнавчий аспект
Стаття присвячена аналізу іконографічних особливостей образу Богородиці в православній традиції. Розглянуто особливості іконографічного зображення, його відмінність від
зображення у творі мистецтва. Проаналізовано чотири основні іконографічні типи й варіанти ікон Богородиці. Показано, що характерною рисою всіх типів ікон Богородиці є їхня христоцентричність та самостійність як духовного атрибута богоспілкування.In the article is analyzed the iconographic features of the Virgin in the Orthodox tradition. The author argues that
Christocentric is the main characteristic of the icons of the Virgin
The complex CBX7-PRMT1 has a critical role in regulating E-cadherin gene expression and cell migration
The Chromobox protein homolog 7 (CBX7) belongs to the Polycomb Group (PcG) family, and, as part of the Polycomb repressive complex (PRC1), contributes to maintain transcriptional gene repression. Loss of CBX7 expression has been reported in several human malignant neoplasias, where it often correlates with an advanced cancer state and poor survival, proposing CBX7 as a candidate tumor-suppressor gene in cancer progression. Indeed, CBX7 is able to positively or negatively regulate the expression of genes involved in cell proliferation and cancer progression, such as E-cadherin, cyclin E, osteopontin, EGR1. To understand the molecular mechanisms that underlie the involvement of CBX7 in cancer progression, we designed a functional proteomic experiment based on CHIP-MS to identify novel CBX7 protein partners. Among the identified CBX7-interacting proteins we focused our attention on the Protein Arginine Methyltransferase 1 (PRMT1) whose critical role in epithelial-mesenchymal transition (EMT), cancer cell migration and invasion has been already reported. We confirmed the interaction between CBX7 and PRMT1 and demonstrated that this interaction is crucial for PRMT1 enzymatic activity both in vitro and in vivo and for the regulation of E-cadherin expression, an important hallmark of EMT. These results suggest a general mechanism by which CBX7 interacting with histone modification enzymes like HDAC2 and PRMT1 enhances E-cadherin expression. Therefore, disruption of this equilibrium may induce impairment of E-cadherin expression and increased cell migration eventually leading to EMT and, then, cancer progression
Liposome-Mediated Delivery Improves the Efficacy of Lisosan G against Retinopathy in Diabetic Mice
Nutraceuticals are natural substances whose anti-oxidant and anti-inflammatory properties may be used to treat retinal pathologies. Their efficacy is limited by poor bioavailability, which could be improved using nanocarriers. Lisosan G (LG), a fermented powder from whole grains, protects the retina from diabetic retinopathy (DR)-induced damage. For this study, we tested whether the encapsulation of LG in liposomes (LipoLG) may increase its protective effects. Diabetes was induced in mice via streptozotocin administration, and the mice were allowed to freely drink water or a water dispersion of two different doses of LG or of LipoLG. Electroretinographic recordings after 6 weeks showed that only the highest dose of LG could partially protect the retina from diabetes-induced functional deficits, while both doses of LipoLG were effective. An evaluation of molecular markers of oxidative stress, inflammation, apoptosis, vascular endothelial growth factor, and the blood-retinal barrier confirmed that the highest dose of LG only partially protected the retina from DR-induced changes, while virtually complete prevention was obtained with either dose of LipoLG. These data indicate that the efficacy of LG in contrasting DR is greatly enhanced by its encapsulation in liposomes and may lay the ground for new dietary supplements with improved therapeutic effects against DR
The effect of marathon on mRNA expression of anti-apoptotic and pro-apoptotic proteins and sirtuins family in male recreational long-distance runners
<p>Abstract</p> <p>Background</p> <p>A large body of evidence shows that a single bout of strenuous exercise induces oxidative stress in circulating human lymphocytes leading to lipid peroxidation, DNA damage, mitochondrial perturbations, and protein oxidation.</p> <p>In our research, we investigated the effect of physical load on the extent of apoptosis in primary cells derived from blood samples of sixteen healthy amateur runners after marathon (a.m.).</p> <p>Results</p> <p>Blood samples were collected from ten healthy amateur runners peripheral blood mononuclear cells (PBMCs) were isolated from whole blood and bcl-2, bax, heat shock protein (HSP)70, Cu-Zn superoxide dismutase (SOD), Mn-SOD, inducible nitric oxide synthase (i-NOS), SIRT1, SIRT3 and SIRT4 (Sirtuins) RNA levels were determined by Northern Blot analysis. Strenuous physical load significantly increased HSP70, HSP32, Mn-SOD, Cu-Zn SOD, iNOS, GADD45, bcl-2, forkhead box O (FOXO3A) and SIRT1 expression after the marathon, while decreasing bax, SIRT3 and SIRT4 expression (P < 0.0001).</p> <p>Conclusion</p> <p>These data suggest that the physiological load imposed in amateur runners during marathon attenuates the extent of apoptosis and may interfere with sirtuin expression.</p
Liposomal Formulations to Improve Antioxidant Power of Myrtle Berry Extract for Potential Skin Application
Many substances in plant extracts are known for their biological activities. These substances act in different ways, exerting overall protective effects against many diseases, especially skin disorders. However, plant extracts’ health benefits are often limited by low bioavailability. To overcome these limitations, drug delivery systems can be employed. In this study, we evaluated the antioxidant power of an ethanolic extract from Myrtus communis L. (myrtle) berries through colorimetric tests (DPPH and FRAP). The antioxidant activity was also verified by using fibroblast cell culture through cellular Reactive Oxygen Species (ROS) levels measurements. Moreover, the myrtle extract was formulated in phospholipid vesicles to improve its bioavailability and applicability. Myrtle liposomes were characterized by size, surface charge, storage stability, and entrapment efficiency; visualized by using cryo-TEM images; and assayed for cytocompatibility and anti-ROS activity. Our results suggest that myrtle liposomes were cytocompatible and improved the extract’s antioxidant power in fibroblasts, suggesting a potential skin application for these formulations and confirming that nanotechnologies could be a valid tool to enhance plant extracts’ potentialities
INFLUENCE OF TEACHING METHODOLOGICAL APPROACHES ON REMOTE CLASSES DURING THE COVID-19 PANDEMIC: THE PERCEPTION OF BRAZILIAN MEDICINE STUDENTS
Introduction: The COVID-19 pandemic required a rapid and unplanned change in medical education. In Brazil, the teaching and learning practices of medical schools with a traditional, active or mixed methodological approach were reformulated. The face-to-face teaching process was replaced by the remote one and significantly impacted the development of activitiesObjective: To assess the influence of teaching methodological approaches on remote classes in the perception of Brazilian medical students during the COVID-19 pandemic.Methods: Descriptive online cross-sectional study carried out between June and October 2020. The study sample consisted of Brazilian medical students aged 18 years and over. A web-based self-reported questionnaire was administered using Google Forms.Results: A total of 353 students from Brazilian medical schools with an active methodological approach (55.2%), mixed (28.9%), and traditional (15.9%) were included in the study. For 53.57%, 40.31%, and 35.05% of students of traditional, active, and mixed methodology, remote classes were considered regular. More than half of the students reported difficulties in concentration and commitment to studies. Perceptions about the advantages, disadvantages, and future impact of remote classes were different between groups of students with traditional, active, and mixed methodology (p<0.05).Conclusion: Faced with the challenges faced by the COVID-19 pandemic, the different methodological approaches to teaching exerted an influence on the perception of medical students about remote classes in the teaching-learning process.Keywords: SARS-CoV-2. Lockdown. Education. Medical. Teaching-Learning. Distance learning.RESUMOIntrodução: A pandemia de COVID-19 exigiu uma mudança rápida e não planejada na educação médica. No Brasil, as práticas de ensino e aprendizagem das escolas médicas com abordagem metodológica tradicional, ativa ou mista foram reformuladas. O processo de ensino presencial foi substituído pelo remoto e impactou significativamente no desenvolvimento das atividadesObjetivo: Avaliar a influência das abordagens metodológicas de ensino em aulas remotas na percepção de estudantes de medicina brasileiros durante a pandemia do COVID-19.Métodos: Estudo transversal descritivo online realizado entre junho e outubro de 2020. A amostra do estudo foi composta por estudantes de medicina brasileiros com idade igual ou superior a 18 anos. Um questionário auto-relatado baseado na web foi administrado usando o Google Forms.Resultados: Foram incluídos no estudo 353 estudantes de escolas médicas brasileiras com abordagem metodológica ativa (55,2%), mista (28,9%) e tradicional (15,9%). Para 53,57%, 40,31% e 35,05% dos alunos da metodologia tradicional, ativa e mista, as aulas remotas foram consideradas regulares. Mais da metade dos alunos relataram dificuldades de concentração e comprometimento com os estudos. As percepções sobre as vantagens, desvantagens e impacto futuro das aulas remotas foram diferentes entre os grupos de alunos com metodologia tradicional, ativa e mista (p<0,05).Conclusão: Diante dos desafios enfrentados pela pandemia do COVID-19, as diferentes abordagens metodológicas de ensino exerceram influência na percepção dos estudantes de medicina sobre aulas remotas no processo de ensino-aprendizagem.Palavras-chave: SARS-CoV-2. Confinamento. Educação. Médico. Ensino-Aprendizagem. Ensino à distância.
Untailored vs. Gender- and Body-Mass-Index-Tailored Skeletal Muscle Mass Index (SMI) to Assess Sarcopenia in Advanced Head and Neck Squamous Cell Carcinoma (HNSCC)
: (1) background: sarcopenia lasting >1 year might be considered a chronic condition in many HNSCC patients. CT-scan-derived skeletal muscle mass Index (SMI) is an established surrogate of sarcopenia; yet, the cut-off reported in the literature (literature-based, lb-SMI < 43.2) is mainly based on the risk of chemoradiotherapy-induced toxicity, and the optimal value to discriminate OS is under-investigated. (2) methods: the effect on OS of the lb-SMI cutoff was compared with an untailored OS-oriented SMI cutoff obtained in a cohort of consecutive advanced HNSCC patients treated with primary chemoradiotherapy, bio-chemotherapy or chemo-immunotherapy (cohort-specific, cs-SMI cutoff). gender- and BMI-tailored (gt-SMI and bt-SMI) cut-offs were also evaluated. cutoff values were identified by using the maximally selected rank statistics for OS. (3) results: In 115 HNSCC patients, the cs-SMI cutoff was 31.50, which was lower compared to the lb-SMI reported cut-off. the optimal cut-off separately determined in females, males, overweight and non-overweight patients were 46.02, 34.37, 27.32 and 34.73, respectively. gt-SMI categorization had the highest effect on survival (p < 0.0001); its prognostic value was independent of the treatment setting or the primary location and was retained in a multivariate cox-regression analysis for OS including other HNSCC-specific prognostic factors (p = 0.0004). (4) conclusions: a tailored SMI assessment would improve clinical management of sarcopenia in chemoradiotherapy-, bio-chemotherapy- or chemo-immunotherapy-treated HNSCC patients. gender-based SMI could be used for prognostication in HNSCC patients
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