196 research outputs found

    Simulated gastrointestinal digestion, intestinal permeation and plasma protein interaction of white, green, and black tea polyphenols

    Get PDF
    The gastrointestinal digestion, intestinal permeation, and plasma protein interaction of polyphenols from a single tea cultivar at different stages of processing (white, green, and black teas) were simulated. The salivary phase contained 74.8-99.5% of native polyphenols, suggesting potential bioavailability of significant amounts of antioxidants through the oral mucosal epithelium that might be gastric sensitive and/or poorly absorbed in the intestine. White tea had the highest content and provided the best intestinal bioaccessibility and bioavailability for catechins. Since most of native catechins were not absorbed, they were expected to accumulate in the intestinal lumen where a potential inhibition capacity of cellular glucose and cholesterol uptake was assumed. The permeated catechins (approximately, 2-15% of intestinal levels) significantly bound (about 37%) to plasma HDLs, suggesting a major role in cholesterol metabolism. White tea and its potential nutraceuticals could be effective in the regulation of plasma glucose and cholesterol levels

    Urantide Conformation and Interaction with the Urotensin-II Receptor

    Get PDF
    Urotensin II (U-II) is a disulfide bridged peptide hormone identified as the ligand of a G protein-coupled receptor. Human U-II (H-Glu-Thr-Pro-Asp-c[Cys-Phe-Trp-Lys-Tyr-Cys]-Val-OH) has been described as the most potent vasoconstrictor compound identified to date. We have previously identified the compound termed urantide (H-Asp-c[Pen-Phe-DTrp-Orn-Tyr-Cys]-Val-OH), which is the most potent UT receptor (UTR) antagonist described to date. Urantide may have potential clinical value in the treatment of atherosclerosis. In the present study, we studied the conformational preferences of urantide in DPC micelles and developed a urantide/UTR interaction model. This model can help the design of novel peptides and small molecules as UTR antagonists

    Combined inhibition of AKT/mTOR and MDM2 enhances Glioblastoma Multiforme cell apoptosis and differentiation of cancer stem cells

    Get PDF
    The poor prognosis of Glioblastoma Multiforme (GBM) is due to a high resistance to conventional treatments and to the presence of a subpopulation of glioma stem cells (GSCs). Combination therapies targeting survival/self-renewal signals of GBM and GSCs are emerging as useful tools to improve GBM treatment. In this context, the hyperactivated AKT/mammalian target of the rapamycin (AKT/mTOR) and the inhibited wild-type p53 appear to be good candidates. Herein, the interaction between these pathways was investigated, using the novel AKT/mTOR inhibitor FC85 and ISA27, which re-activates p53 functionality by blocking its endogenous inhibitor murine double minute 2 homologue (MDM2). In GBM cells, FC85 efficiently inhibited AKT/mTOR signalling and reactivated p53 functionality, triggering cellular apoptosis. The combined therapy with ISA27 produced a synergic effect on the inhibition of cell viability and on the reactivation of p53 pathway. Most importantly, FC85 and ISA27 blocked proliferation and promoted the differentiation of GSCs. The simultaneous use of these compounds significantly enhanced GSC differentiation/apoptosis. These findings suggest that FC85 actively enhances the downstream p53 signalling and that a combination strategy aimed at inhibiting the AKT/mTOR pathway and re-activating p53 signalling is potentially effective in GBM and in GSCs

    Biophysical and biochemical characterization of a liposarcoma-derived recombinant MnSOD protein acting as an anticancer agent

    Get PDF
    A recombinant MnSOD (rMnSOD) synthesized by specific cDNA clones derived from a liposarcoma cell line was shown to have the same sequence as the wild-type MnSOD expressed in the human myeloid leukaemia cell line U937, except for the presence of the leader peptide at the N-terminus. These results were fully confirmed by the molecular mass of rMnSOD as evaluated by ES/MS analysis (26662.7 Da) and the nucleotide sequence of the MnSOD cDNA. The role of the leader peptide in rMnSOD was investigated using a fluorescent and/or 68Gallium-labelled synthetic peptide. The labelled peptide permeated MCF-7 cells and uptake could be inhibited in the presence of an excess of oestrogen. In vivo it was taken up by the tumour, suggesting that the molecule can be used for both therapy and diagnosis. The in vitro and in vivo pharmacology tests confirmed that rMnSOD is only oncotoxic for tumour cells expressing oestrogen receptors. Pharmacokinetic studies in animals performed with 125I- and 131I-labelled proteins confirmed that, when administered systemically, rMnSOD selectively reached the tumour, where its presence was unambiguously demonstrated by scintigraphic and PET scans. PCR analysis revealed that Bax gene expression was increased and the Bcl2 gene was down regulated in MCF7 cells treated with rMnSOD, which suggests that the protein induces a pro-apoptotic mechanism

    Detailed peptide profiling of “Scotta”: from a dairy waste to a source of potential health-promoting compound

    Get PDF
    “Scotta” is a liquid waste deriving from Ricotta cheese production, which is wrongly considered only a dairy by-product. In this work, with the aim to elucidate the presence of valuable bioactive compounds in Buffalo’s Scotta, a peptide fraction under 3000 Da was isolated by ultra-filtration, purified by solid-phase extraction, and,subsequently, characterized in detail by liquid chromatography coupled to Orbitrap mass spectrometry. Analytical results revealed a complex profile, leading to the identification of 226 peptides, belonging to alpha, beta, and kappa caseins. A database-driven search approach was used to assess the biological effects of some of the identified peptides. A wide range of healthy properties was ascribed to the encrypted peptides, comprising antihypertensive, antimicrobial, immunomodulating, opioid, antioxidant, and antithrombotic. The peptidomic profile of Scotta was highlighted in depth for the first time, and the results revealed that this matrix should not be considered only a mere by-product, but a source of potential health-promoting peptides, which can be recovered and employed in nutraceuticals and functional foods

    Superficial siderosis of the central nervous system: case report

    Get PDF
    Introdução: A Siderose Superficial do Sistema Nervoso Central (SS) é uma doença rara caracterizada pelo depósito de hemossiderina no encéfalo e na medula espinhal. Clinicamente se caracteriza por ataxia e surdez neurossensorial progressivas associados a lesão do neurônio motor superior. O diagnóstico é feito através do exame de ressonância nuclear magnética (RNM) de Encéfalo e Medula Espinhal. Objetivo: Relatar um caso de paciente com elementos característicos da síndrome, associados à presença incomum de epilepsia. Método: Relatamos o caso de um paciente com SS acompanhado no Instituto de Neurologia Deolindo Couto da UFRJ-RJ. Conclusão: A Siderose Superficial do Sistema Nervoso Central é uma afecção do SNC que deve ser pensada em todo paciente com quadro de ataxia e surdez neurossensorial progressivas, necessitando de RNM, preferencialmente as imagens de Gradiente eco em T2 para o diagnóstico.Introduction: Superficial Siderosis Central Nervous System (SS) is a rare disease characterized by the deposition of hemosiderin in the brain and spinal cord. Clinically there is progressive ataxia and sensorineural deafness associated with upper motor neuron lesion. The diagnosis is made by examination of magnetic resonance imaging (MRI) Brain and Spinal Cord. Objective: Report a case of a patient with characteristic features of the syndrome, associated with the unusual presence of epilepsy. Method: We report the case of a patient with SS followed at the Institute of Neurology Deolindo Couto da UFRJ-RJ. Conclusion: The Superficial Siderosis Central Nervous System is a disease of the CNS that must be considered in any patient with ataxia and progressive deafness, requiring MRI, preferably images Gradient echo T2 for diagnosis

    Synthesis and cytotoxic activity evaluation of 2,3-thiazolidin-4-one derivatives on human breast cancer cell lines

    Get PDF
    It is well known that resveratrol (RSV) displayed cancer-preventing and anticancer properties but its clinical application is limited because of a low bioavailability and a rapid clearance from the circulation. Aim of this work was to synthesize pharmacologically active resveratrol analogs with an enhanced structural rigidity and bioavailability. In particular, we have synthesized a library of 2,3-thiazolidin-4-one derivatives in which a thiazolidinone nucleus connects two aromatic rings. Some of these compounds showed strong inhibitory effects on breast cancer cell growth. Our results indicate that some of thiazolidin-based resveratrol derivatives may become a new potent alternative tool for the treatment of human breast cancer

    Fraqueza muscular adquirida na UTI (ICU-AW): efeitos sistêmicos da eletroestimulação neuromuscular

    Get PDF
    Com os avanços tecnológicos alcançados atualmente na terapia intensiva e maior sobrevida dos pacientes, outros desafios têm surgido para os profissionais de saúde. Dentre alguns, destaca-se a fraqueza muscular adquirida na UTI (ICU-AW), caracterizada por paresia esquelética e respiratória dos músculos promovendo aumento nastaxas de mortalidade e comprometimento da qualidade de vida. Sua incidência varia de 30% a 60% e tem na síndrome da resposta inflamatória sistêmica (SIRS) e na disfunção de múltiplos órgãos (DMO) sua principal etiologia. Outros fatores de risco como a hiperglicemia,o uso de bloqueadores neuromusculares e sedativos, a imobilidade e a própria ventilação mecânica estão entre os mais comuns. Entre as medidas de combate à ICU-AW, está o conceito de mobilização precoce, bem como despertar diário e controle estreito da glicemia. Nesse contexto, a eletroestimulação muscular apresenta-se como recurso de grande valia. Sua principal vantagem está no fato de poder ser empreendida independentemente da cooperação do paciente, epor ser capaz de gerar respostas musculares eficientes, bem como resultados satisfatórios na preservação da massa muscular, condicionamento físico e funcionalidade dos que usam essa ferramenta. Desfechos interessantes têm sido observados em diversos perfis de pacientes, como os de doença pulmonar obstrutiva crônica (DPOC)e traumatismo raquimedular (TRM). No paciente crítico, seu uso tem mostrado redução nos tempos de ventilação mecânica (VM), internação na UTI e maior funcionalidade dos pacientes. A relevância dos efeitos sistêmicos e metabólicos provenientes da eletroestimulação neuromuscular (ENM) tem sido a base para os estudos nos pacientes críticos. Portanto, a ICU-AW é uma realidade no cenário da terapia intensiva e sua prevenção tem dado margem à aparição de novas propostas e ferramentas na prevenção dessas complicações

    Revisiting the term neuroprotection in chronic and degenerative diseases

    Get PDF
    Thanks to the development of several new researches, the lifetime presented a significant increase, even so, we still have many obstacles to overcome - among them, manage and get responses regarding neurodegenerative diseases. Where we are in the understanding of neuroprotection? Do we really have protective therapies for diseases considered degeneratives such as amyotrophic lateral sclerosis and its variants, Parkinson's disease, Alzheimer's disease and many others? Neuroprotection is defined by many researches as interactions and interventions that can slow down or even inhibit the progression of neuronal degeneration process. We make some considerations on this neuroprotective effect.Department of Neurology, Antonio Pedro University Hospital, Fluminense Federal University , NiteróiNeurology Service, Nova Iguaçu Hospital , PosseBrain Mapping Laboratory and Electroencephalogram, Federal University of Rio de JaneiroBrain Mapping and Functionality Laboratory, Federal University of PiauíSeverino Sombra University Center, School of Medicine , VassourasDepartment of Neurology, Federal University of São Paulo , BrazilDepartment of Neurology, Federal University of São Paulo , BrazilWeb of Scienc

    Randomized Clinical Trials and Observational Tribulations: Providing Clinical Evidence for Personalized Surgical Pain Management Care Models

    Get PDF
    Proving clinical superiority of personalized care models in interventional and surgical pain management is challenging. The apparent difficulties may arise from the inability to standardize complex surgical procedures that often involve multiple steps. Ensuring the surgery is performed the same way every time is nearly impossible. Confounding factors, such as the variability of the patient population and selection bias regarding comorbidities and anatomical variations are also difficult to control for. Small sample sizes in study groups comparing iterations of a surgical protocol may amplify bias. It is essentially impossible to conceal the surgical treatment from the surgeon and the operating team. Restrictive inclusion and exclusion criteria may distort the study population to no longer reflect patients seen in daily practice. Hindsight bias is introduced by the inability to effectively blind patient group allocation, which affects clinical result interpretation, particularly if the outcome is already known to the investigators when the outcome analysis is performed (often a long time after the intervention). Randomization is equally problematic, as many patients want to avoid being randomly assigned to a study group, particularly if they perceive their surgeon to be unsure of which treatment will likely render the best clinical outcome for them. Ethical concerns may also exist if the study involves additional and unnecessary risks. Lastly, surgical trials are costly, especially if the tested interventions are complex and require long-term follow-up to assess their benefit. Traditional clinical testing of personalized surgical pain management treatments may be more challenging because individualized solutions tailored to each patient’s pain generator can vary extensively. However, high-grade evidence is needed to prompt a protocol change and break with traditional image-based criteria for treatment. In this article, the authors review issues in surgical trials and offer practical solutions
    corecore