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1.
Int J Mol Sci ; 25(12)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38928461

RESUMO

"Core/shell" composites are based on a ferrite core coated by two layers with different properties, one of them is an isolator, SiO2, and the other is a semiconductor, TiO2. These composites are attracting interest because of their structure, photocatalytic activity, and magnetic properties. Nanocomposites of the "core/shell" МFe2O4/SiO2/TiO2 (М = Zn(II), Co(II)) type are synthesized with a core of MFe2O4 produced by two different methods, namely the sol-gel method (SG) using propylene oxide as a gelling agent and the hydrothermal method (HT). SiO2 and TiO2 layer coating is performed by means of tetraethylorthosilicate, TEOS, Ti(IV) tetrabutoxide, and Ti(OBu)4, respectively. A combination of different experimental techniques is required to prove the structure and phase composition, such as XRD, UV-Vis, TEM with EDS, photoluminescence, and XPS. By Rietveld analysis of the XRD data unit cell parameters, the crystallite size and weight fraction of the polymorphs anatase and rutile of the shell TiO2 and of the ferrite core are determined. The magnetic properties of the samples, and their activity for the photodegradation of the synthetic industrial dyes Malachite Green and Rhodamine B are measured in model water solutions under UV light irradiation and simulated solar irradiation. The influence of the water matrix on the photocatalytic activity is determined using artificial seawater in addition to ultrapure water. The rate constants of the photocatalytic process are obtained along with the reaction mechanism, established using radical scavengers where the role of the radicals is elucidated.


Assuntos
Nanocompostos , Rodaminas , Corantes de Rosanilina , Titânio , Poluentes Químicos da Água , Nanocompostos/química , Corantes de Rosanilina/química , Catálise , Poluentes Químicos da Água/química , Rodaminas/química , Titânio/química , Fotólise , Dióxido de Silício/química , Compostos Férricos/química , Processos Fotoquímicos , Difração de Raios X
2.
Int J Mol Sci ; 24(21)2023 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-37958947

RESUMO

Ionizing radiation (IR) and reactive oxygen species (ROS)-induced oxidative stress can cause damage to cellular biomolecules, including DNA, proteins, and lipids. These harmful effects can compromise essential cellular functions and significantly raise the risk of metabolic dysfunction, accumulation of harmful mutations, genome instability, cancer, accelerated cellular senescence, and even death. Here, we present an investigation of HeLa cancer cells' early response to gamma IR (γ-IR) and oxidative stress after preincubation of the cells with natural extracts of the resurrection plant Haberlea rhodopensis. In light of the superior protection offered by plant extracts against radiation and oxidative stress, we investigated the cellular defence mechanisms involved in such protection. Specifically, we sought to evaluate the molecular effects of H. rhodopensis extract (HRE) on cells subjected to genotoxic stress by examining the components of the redox pathway and quantifying the transcription levels of several critical genes associated with DNA repair, cell cycle regulation, and apoptosis. The influence of HRE on genome integrity and the cell cycle was also studied via comet assay and flow cytometry. Our findings demonstrate that HREs can effectively modulate the cellular response to genotoxic and oxidative stress within the first two hours following exposure, thereby reducing the severity of such stress. Furthermore, we observed the specificity of genoprotective HRE doses depending on the source of the applied genotoxic stress.


Assuntos
Lamiales , Oxirredução , Estresse Oxidativo , Extratos Vegetais/farmacologia , Dano ao DNA , Expressão Gênica , Espécies Reativas de Oxigênio
3.
Molecules ; 27(21)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36364401

RESUMO

G-quadruplexes (GQs) have become valid targets for anticancer studies in recent decades due to their multifaceted biological function. Herewith, we aim to quantify interactions of potential heterocyclic ligands (Ls) with model GQs. For seven 4-aminoquinazolines and three 2-heteroaryl perimidines, seven of this ten-membered group so far unknown, we use routine quantum chemical modeling. As shown in the literature, a preferred mode of interaction of heterocycles with cellular structures is stacking to exposable faces of G-quadruplexes. To exploit the energy of this interaction as a molecular descriptor and achieve the necessary chemical precision, we use state of the art large-scale density functional theory (DFT) calculations of stacked heterocycles to a GQ. Actually, the GQ has been simplified for the computation by stripping it off all pentose phosphate residues into a naked model of stacked guanine quartets. The described model thus becomes computable. The obtained heterocyclic ligand GQ.L stacking energies, that is, their GQ affinities, are the necessary ligand descriptors. Using the ligand biological inhibitory activities (IC50) on a human malignant melanoma A375 cell line, we obtain a good linear relationship between computed ligand stacking affinities to GQ, and experimental log (IC50) values. Based on the latter relationship, we discuss a putative mechanism of anticancer activity of heterocyclic ligands via stacking interactions with GQs and thereby controlling cell regulatory activity. This mechanism may tentatively be applied to other condensed five- and six-membered small heterocycles as well.


Assuntos
Antineoplásicos , Quadruplex G , Humanos , Ligantes , Relação Quantitativa Estrutura-Atividade , Antineoplásicos/química
4.
Int J Mol Sci ; 21(7)2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32244505

RESUMO

Clinically, there is an urgent need to identify new therapeutic strategies for selectively treating cancer cells. One of the directions in this research is the development of biocompatible therapeutics that selectively target cancer cells. Here, we show that novel aminated graphene oxide (haGO-NH2) nanoparticles demonstrate increased toxicity towards human hepatocellular cancer cells compared to pristine graphene oxide(GO). The applied novel strategy for amination leads to a decrease in the size of haGO-NH2 and their zeta potential, thus, assuring easier penetration through the cell membrane. After characterization of the biological activities of pristine and aminated GO, we have demonstrated strong cytotoxicity of haGO-NH2 toward hepatic cancer cells - HepG2 cell line, in a dose-dependent manner. We have presented evidence that the cytotoxic effects of haGO-NH2 on hepatic cancer cells were due to cell membrane damage, mitochondrial dysfunction and increased reactive oxygen species (ROS) production. Intrinsically, our current study provides new rationale for exploiting aminated graphene oxide as an anticancer therapeutic.


Assuntos
Carcinoma Hepatocelular/metabolismo , Grafite/farmacologia , Neoplasias Hepáticas/metabolismo , Aminação , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Membrana Celular , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Mitocôndrias , Nanopartículas , Espécies Reativas de Oxigênio
5.
Crit Care Med ; 46(7): 1085-1092, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29608513

RESUMO

OBJECTIVES: To determine the predictive value of commonly used clinical variables upon ICU admission for long-term all-cause mortality and functional outcome of adult stroke patients admitted to the ICU. DESIGN: Retrospective observational cohort study. SETTING: General and neurosurgical ICUs of the University College London Hospitals in North Central London. PATIENTS: All adult ICU patients with a clinical diagnosis of acute stroke admitted between February 2010 and May 2012. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Demographic and clinical data concerning the first 24 hours after ICU admission were obtained. Patients were followed until February 2016 to assess long-term survival. Functional outcome was determined using the modified Rankin Scale. We evaluated 131 critically ill stroke patients, with a median (interquartile range) age of 70 years (55-78 yr). One-year mortality rate was 52.7%. Surviving patients were followed up over a median (interquartile range) period of 4.3 years (4.0-4.8 yr). The multivariable model that best predicted long-term all-cause mortality indicated that mortality of critically ill stroke patients was predicted by high Acute Physiology and Chronic Health Evaluation II score, impaired consciousness (Glasgow Coma Scale score ≤ 8) as reason for ICU admission, low Glasgow Coma Scale sum score after 24 hours, and absence of brainstem reflexes. Long-term independent functional status occurred in 30.9% of surviving patients and was predicted by low Acute Physiology and Chronic Health Evaluation II score, high Glasgow Coma Scale sum score at ICU admission, and absence of mass effect on CT scan. CONCLUSIONS: Mortality in critically ill stroke patients is high and occurs most often shortly after the event. Less than one in three surviving patients is able to function independently after 1 year. This study has identified several clinical variables that predict long-term all-cause mortality and functional outcome among critically ill stroke patients and found that mainly acute physiologic disturbance and absolute values of neurologic clinical assessment are predictive.


Assuntos
Cuidados Críticos , Acidente Vascular Cerebral/terapia , APACHE , Idoso , Idoso de 80 Anos ou mais , Feminino , Escala de Coma de Glasgow , Humanos , Unidades de Terapia Intensiva/estatística & dados numéricos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Recuperação de Função Fisiológica , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/mortalidade , Resultado do Tratamento
6.
Int J Mol Sci ; 19(12)2018 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-30544895

RESUMO

The principal focus of this work is the in-depth analysis of the biological efficiency of inorganic calcium-filled bacterial cellulose (BC) based hydrogel scaffolds for their future use in bone tissue engineering/bioengineering. Inorganic calcium was filled in the form of calcium phosphate (ß-tri calcium phosphate (ß-TCP) and hydroxyapatite (HA)) and calcium carbonate (CaCO3). The additional calcium, CaCO3 was incorporated following in vitro bio-mineralization. Cell viability study was performed with the extracts of BC based hydrogel scaffolds: BC-PVP, BC-CMC; BC-PVP-ß-TCP/HA, BC-CMC-ß-TCP/HA and BC-PVP-ß-TCP/HA-CaCO3, BC-CMC-ß-TCP/HA-CaCO3; respectively. The biocompatibility study was performed with two different cell lines, i.e., human fibroblasts, Lep-3 and mouse bone explant cells. Each hydrogel scaffold has facilitated notable growth and proliferation in presence of these two cell types. Nevertheless, the percentage of DNA strand breaks was higher when cells were treated with BC-CMC based scaffolds i.e., BC-CMC-ß-TCP/HA and BC-CMC-ß-TCP/HA-CaCO3. On the other hand, the apoptosis of human fibroblasts, Lep-3 was insignificant in BC-PVP-ß-TCP/HA. The scanning electron microscopy confirmed the efficient adhesion and growth of Lep-3 cells throughout the surface of BC-PVP and BC-PVP-ß-TCP/HA. Hence, among all inorganic calcium filled hydrogel scaffolds, 'BC-PVP-ß-TCP/HA' was recommended as an efficient tissue engineering scaffold which could facilitate the musculoskeletal (i.e., bone tissue) engineering/bioengineering.


Assuntos
Osso e Ossos/citologia , Cálcio/química , Celulose/química , Hidrogéis/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Durapatita/química , Humanos , Camundongos
7.
FEMS Yeast Res ; 16(4)2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27189369

RESUMO

Linker histones are essential components of chromatin in eukaryotes. Through interactions with linker DNA and nucleosomes they facilitate folding and maintenance of higher-order chromatin structures and thus delicately modulate gene activity. The necessity of linker histones in lower eukaryotes appears controversial and dubious. Genomic data have shown that Schizosaccharomyces pombe does not possess genes encoding linker histones while Kluyveromyces lactis has been reported to have a pseudogene. Regarding this controversy, we have provided the first direct experimental evidence for the existence of a functional linker histone gene, KlLH1, in K. lactis genome. Sequencing of KlLH1 from both genomic DNA and copy DNA confirmed the presence of an intact open reading frame. Transcription and splicing of the KlLH1 sequence as well as translation of its mRNA have been studied. In silico analysis revealed homology of KlLH1p to the histone H1/H5 protein family with predicted three domain structure characteristic for the linker histones of higher eukaryotes. This strongly proves that the yeast K. lactis does indeed possess a functional linker histone gene thus entailing the evolutionary preservation and significance of linker histones. The nucleotide sequences of KlLH1 are deposited in the GenBank under accession numbers KT826576, KT826577 and KT826578.


Assuntos
Histonas/genética , Histonas/metabolismo , Kluyveromyces/enzimologia , Kluyveromyces/genética , Fases de Leitura Aberta , Biossíntese de Proteínas , Splicing de RNA , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Transcrição Gênica
8.
Electrophoresis ; 36(20): 2553-60, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26178261

RESUMO

Comet assay is an invaluable tool in DNA research. It is widely used to detect DNA damage as an indicator of exposure to genotoxic stress. A canonical set of parameters and specialized software programs exist for Comet assay data quantification and analysis. None of them so far has proven its potential to employ a computer-based algorithm for assessment of the shape of the comet as an indicator of the exact mechanism by which the studied genotoxins cut in the molecule of DNA. Here, we present 14 unique measurements of the comet image based on the comet morphology. Their mathematical derivation and statistical analysis allowed precise description of the shape of the comet image which in turn discriminated the cause of genotoxic stress. This algorithm led to the development of the "CometShape" software which allowed easy discrimination among different genotoxins depending on the type of DNA damage they induce.


Assuntos
Ensaio Cometa/métodos , Quebras de DNA de Cadeia Simples/efeitos dos fármacos , Processamento de Imagem Assistida por Computador/métodos , Testes de Mutagenicidade/métodos , Software , Algoritmos , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Humanos , Mutagênicos/toxicidade
9.
Biogerontology ; 16(4): 461-72, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25758774

RESUMO

Bioactive substances that are found in many natural plant extracts are very important for the cosmetics, pharmaceutical industry and biotechnology. Especially interesting for these industries are the substances that possess cell revitalizing and anti-ageing properties. The endemic plant Haberlea rhodopensis is known for its ability to withstand drought and to revitalize when returned to optimal conditions after a long time in desiccation. It is a mere fact that this plant not only can completely resurrect from a dried state but is also able to bring back the natural biochemical compositions of its cells. As a result H. rhodopensis offers a wide field for investigation of the exact mechanisms of the revitalization process as well as broadens the search for unique bioactive chemical substances in its cells. Here, by using the yeast Saccharomyces cerevisiae as a model we have demonstrated that methanol extracts from the plant H. rhodopensis hold specific properties to revitalize and ameliorate cellular growth as well as to balance intracellular metabolic states. Our results add valuable knowledge on the effects of natural compounds on ageing and reinforce the idea of using yeast as a model organism in the development of rapid tests for studying the efficacy of different bioactive substances.


Assuntos
Magnoliopsida , Metanol/química , Viabilidade Microbiana/efeitos dos fármacos , Extratos Vegetais/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Solventes/química , Metabolismo Energético/efeitos dos fármacos , Magnoliopsida/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta , Plantas Medicinais , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Fatores de Tempo
10.
Pharmaceuticals (Basel) ; 17(6)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38931344

RESUMO

Nanotechnology has emerged as a transformative force in oncology, facilitating advancements in site-specific cancer therapy and personalized oncomedicine. The development of nanomedicines explicitly targeted to cancer cells represents a pivotal breakthrough, allowing the development of precise interventions. These cancer-cell-targeted nanomedicines operate within the intricate milieu of the tumour microenvironment, further enhancing their therapeutic efficacy. This comprehensive review provides a contemporary perspective on precision cancer medicine and underscores the critical role of nanotechnology in advancing site-specific cancer therapy and personalized oncomedicine. It explores the categorization of nanoparticle types, distinguishing between organic and inorganic variants, and examines their significance in the targeted delivery of anticancer drugs. Current insights into the strategies for developing actively targeted nanomedicines across various cancer types are also provided, thus addressing relevant challenges associated with drug delivery barriers. Promising future directions in personalized cancer nanomedicine approaches are delivered, emphasising the imperative for continued optimization of nanocarriers in precision cancer medicine. The discussion underscores translational research's need to enhance cancer patients' outcomes by refining nanocarrier technologies in nanotechnology-driven, site-specific cancer therapy.

11.
Heliyon ; 10(7): e28621, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38586359

RESUMO

Natural deep eutectic solvents (NADESs) have been considered promising to replace traditional volatile and toxic organic solvents for the extraction of biologically active substances from natural sources. This work applied an efficient and ethanol-exclusion strategy for extraction of phenolic compounds from poplar type propolis using five known NADESs (lactic acid:1,2-propanediol 1:1, lactic acid:fructose 5:1, choline chloride:1,2-propanediol 1:3, choline chloride:1,2-propanediol:water 1:1:1 and betaine:malic acid:water 1:1:6). The selected NADESs' extractability was evaluated by measuring the concentrations of total phenolics and total flavones and flavonols in the propolis extracts obtained, which qualitative chemical composition was further determined in detail by gas chromatography-mass spectrometry (GC-MS) analysis. It demonstrated that the chemical profiles of NADES and 70% ethanolic propolis extracts are similar. To expand the knowledge about the role of the applied solvents in the poplar propolis extraction process, the in vitro antimicrobial, cytotoxic and genotoxic activity of both NADESs and liquid NADES extracts were evaluated. The results revealed that the use of the selected NADESs as an extraction media for phenolic compounds from poplar propolis not only delivered a good extraction yield in some cases, but generally led to the preservation of propolis extracts' biological activity and even to the enhancement of their antimicrobial effect in comparison with the hydroethanolic one. Besides, the tested NADESs except for lactic acid:fructose and betaine:malic acid:water exerted low to negligible toxicity against normal cells treated and apart from lactic acid:fructose the remaining solvents demonstrated concentration-dependent moderate to subtle genotoxicity. There is a probability that not the supramolecular structure of the NADESs, but their components, played a key role for the observed biological effects. The present study has demonstrated an alternative approach for extracting the biologically active complex from poplar type propolis using NADESs, which could be useful for further pharmaceutical and cosmeceutical applications.

12.
Biochim Biophys Acta ; 1819(5): 366-74, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22200500

RESUMO

Despite the existence of certain differences between yeast and higher eukaryotic cells a considerable part of our knowledge on chromatin structure and function has been obtained by experimenting on Saccharomyces cerevisiae. One of the peculiarities of S. cerevisiae cells is the unusual and less abundant linker histone, Hho1p. Sparse is the information about Hho1p involvement in yeast higher-order chromatin organization. In an attempt to search for possible effects of Hho1p on the global organization of chromatin, we have applied Chromatin Comet Assay (ChCA) on HHO1 knock-out yeast cells. The results showed that the mutant cells exhibited highly distorted higher-order chromatin organization. Characteristically, linker histone depleted chromatin generally exhibited longer chromatin loops than the wild-type. According to the Atomic force microscopy data the wild-type chromatin appeared well organized in structures resembling quite a lot the "30-nm" fiber in contrast to HHO1 knock-out yeast.


Assuntos
Cromatina/ultraestrutura , Cromossomos/ultraestrutura , Histonas , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Cromatina/genética , Cromatina/metabolismo , Regulação Fúngica da Expressão Gênica , Técnicas de Inativação de Genes , Histonas/genética , Histonas/metabolismo , Histonas/ultraestrutura , Microscopia de Força Atômica , Mutação , Nucleossomos/genética , Nucleossomos/ultraestrutura , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/ultraestrutura , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/ultraestrutura , Transcrição Gênica
13.
Antonie Van Leeuwenhoek ; 103(1): 143-52, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22914887

RESUMO

Kluyveromyces lactis, also known as dairy yeast, has numerous applications in scientific research and practice. It has been approved as a GRAS (Generally Recognized As Safe) organism, a probiotic, a biotechnological producer of important enzymes at industrial scale and a bioremediator of waste water from the dairy industry. Despite these important practical applications the sensitivity of this organism to genotoxic substances has not yet been assessed. In order to evaluate the response of K. lactis cells to genotoxic agents we have applied several compounds with well-known cyto- and genotoxic activity. The method of comet assay (CA) widely used for the assessment of DNA damages is presented here with new special modifications appropriate for K. lactis cells. The comparison of the response of K. lactis to genotoxins with that of Saccharomyces cerevisiae showed that both yeasts, although considered close relatives, exhibit species-specific sensitivity toward the genotoxins examined.


Assuntos
Dano ao DNA , DNA Bacteriano/efeitos dos fármacos , Kluyveromyces/efeitos dos fármacos , Mutagênicos/toxicidade , Ensaio Cometa
14.
Acta Neurochir (Wien) ; 155(8): 1437-42, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23812966

RESUMO

BACKGROUND: Histones are proteins closely associated with the DNA molecules and serve as a structural scaffold for the organization of chromatin. They play an important role in the regulation of gene expression by changing the level of DNA compaction. The special subtype of the linker histone family-H1 zero (H1.0) is generally expressed in non-dividing, terminally differentiated cells. The aim of our study is to investigate the correlation between the quantities of histone H1.0 in human gliomas, the histopathological grade and the overall survival. MATERIAL AND METHOD: Twenty-nine (N = 29) patients with intraaxial lesions underwent a microsurgical tumor resection. Tumor samples were snap-frozen in liquid nitrogen immediately after resection. Following a specific protocol, linker histones were extracted from the tumor specimens and the quantities of histone H1.0 were assessed. All patients were followed up prospectively. RESULTS: Of the 29 patients in our study (M:F = 17:12), five had a grade II astrocytoma, seven had a grade III, and 17 had a grade IV, according to the World Health Organization (WHO) classification. At the end of the study, three patients were still alive. The mean quantities of H1.0 were: 23.3 for grade II tumors, 13.9 for grade III and 11.3 for grade IV tumors. The statistical analysis demonstrated that the histological grade, age and Karnofsky performance status (KPS) remain among the most reliable predictive factors for the survival of patients with gliomas. Grade III-IV gliomas had significantly less histone H1.0 than grade II gliomas. Conformably, in a multivariate Cox regression analysis, H1.0 made a small but significant contribution (p < 0.05) to survival rates. CONCLUSION: Our study confirmed that histone H1.0 is a potential biological marker with prognostic value for the survival of patients with gliomas. The quantities of histone H1.0 are correlated to the histopathological grade of the tumor. The more aggressive and malignant gliomas tend to have lower quantities of histone H1.0.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidade , Glioma/metabolismo , Glioma/mortalidade , Histonas/metabolismo , Adulto , Idoso , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Feminino , Glioma/patologia , Glioma/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores/métodos , Prognóstico , Análise de Regressão , Taxa de Sobrevida
15.
Eur Heart J ; 33(7): 895-903, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21911341

RESUMO

AIMS: Systolic dysfunction in septic shock is well recognized and, paradoxically, predicts better outcome. In contrast, diastolic dysfunction is often ignored and its role in determining early mortality from sepsis has not been adequately investigated. METHODS AND RESULTS: A cohort of 262 intensive care unit patients with severe sepsis or septic shock underwent two echocardiography examinations early in the course of their disease. All clinical, laboratory, and survival data were prospectively collected. Ninety-five (36%) patients died in the hospital. Reduced mitral annular e'-wave was the strongest predictor of mortality, even after adjusting for the APACHE-II score, low urine output, low left ventricular stroke volume index, and lowest oxygen saturation, the other independent predictors of mortality (Cox's proportional hazards: Wald = 21.5, 16.3, 9.91, 7.0 and 6.6, P< 0.0001, <0.0001, 0.002, 0.008, and 0.010, respectively). Patients with systolic dysfunction only (left ventricular ejection fraction ≤50%), diastolic dysfunction only (e'-wave <8 cm/s), or combined systolic and diastolic dysfunction (9.1, 40.4, and 14.1% of the patients, respectively) had higher mortality than those with no diastolic or systolic dysfunction (hazard ratio = 2.9, 6.0, 6.2, P= 0.035, <0.0001, <0.0001, respectively) and had significantly higher serum levels of high-sensitivity troponin-T and N-terminal pro-B-type natriuretic peptide (NT-proBNP). High-sensitivity troponin-T was only minimally elevated, whereas serum levels of NT-proBNP were markedly elevated [median (inter-quartile range): 0.07 (0.02-0.17) ng/mL and 5762 (1001-15 962) pg/mL, respectively], though both predicted mortality even after adjusting for highest creatinine levels (Wald = 5.8, 21.4 and 2.3, P= 0.015, <0.001 and 0.13). CONCLUSION: Diastolic dysfunction is common and is a major predictor of mortality in severe sepsis and septic shock.


Assuntos
Insuficiência Cardíaca Diastólica/mortalidade , Sepse/mortalidade , Disfunção Ventricular Esquerda/mortalidade , Adulto , Idoso , Cuidados Críticos , Ecocardiografia , Feminino , Insuficiência Cardíaca Diastólica/sangue , Mortalidade Hospitalar , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/metabolismo , Fragmentos de Peptídeos/metabolismo , Estudos Prospectivos , Sepse/sangue , Sepse/etiologia , Choque Séptico/sangue , Choque Séptico/etiologia , Choque Séptico/mortalidade , Troponina T/metabolismo , Disfunção Ventricular Esquerda/sangue
16.
Exp Gerontol ; 184: 112334, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37977514

RESUMO

Recent scientific interest has been directed towards age-related diseases, driven by the significant increase in global life expectancy and the growing population of individuals aged 65 and above. The ageing process encompasses various biological, physiological, environmental, psychological, behavioural, and social changes, leading to an augmented susceptibility to chronic illnesses. Cardiovascular, neurological, musculoskeletal, liver and oncological diseases are prevalent in the elderly. Moreover, ageing individuals demonstrate reduced regenerative capacity and decreased tolerance towards therapeutic interventions, including organ transplantation. Liver diseases, such as non-alcoholic fatty liver disease, alcoholic liver disease, hepatitis, fibrosis, and cirrhosis, have emerged as significant public health concerns. Paradoxically, these conditions remain underestimated despite their substantial global impact. Age-related factors are closely associated with the severity and unfavorable prognosis of various liver diseases, warranting further investigation to enhance clinical management and develop novel therapeutic strategies. This comprehensive review focuses specifically on age-related liver diseases, their treatment strategies, and contemporary practices. It provides a detailed account of the global burden, types, molecular mechanisms, and epigenetic alterations underlying these liver pathologies.


Assuntos
Cirrose Hepática , Hepatopatia Gordurosa não Alcoólica , Idoso , Humanos , Fatores de Risco , Cirrose Hepática/complicações , Cirrose Hepática/patologia , Hepatopatia Gordurosa não Alcoólica/terapia , Prognóstico
17.
Gels ; 9(5)2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37232957

RESUMO

Novel composite hydrogels based on poly(acrylic acid-co-acrylamide)/polyacrylamide pseudo-interpenetrating polymer networks (pIPNs) and magnetite were prepared via in situ precipitation of Fe3+/Fe2+ ions within the hydrogel structure. The magnetite formation was confirmed by X-ray diffraction, and the size of the magnetite crystallites was shown to depend on the hydrogel composition: the crystallinity of the magnetite particles increased in line with PAAM content within the composition of the pIPNs. The Fourier transform infrared spectroscopy revealed an interaction between the hydrogel matrix, via the carboxylic groups of polyacrylic acid, and Fe ions, which strongly influenced the formation of the magnetite articles. The composites' thermal properties, examined using differential scanning calorimetry (DSC), show an increase in the glass transition temperature of the obtained composites, which depends on the PAA/PAAM copolymer ratio in the pIPNs' composition. Moreover, the composite hydrogels exhibit pH and ionic strength responsiveness as well as superparamagnetic properties. The study revealed the potential of pIPNs as matrices for controlled inorganic particle deposition as a viable method for the production of polymer nanocomposites.

18.
J Fungi (Basel) ; 9(3)2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36983497

RESUMO

Mitochondria are multifunctional, dynamic organelles important for stress response, cell longevity, ageing and death. Although the mitochondrion has its genome, nuclear-encoded proteins are essential in regulating mitochondria biogenesis, morphology, dynamics and function. Moreover, chromatin structure and epigenetic mechanisms govern the accessibility to DNA and control gene transcription, indirectly influencing nucleo-mitochondrial communications. Thus, they exert crucial functions in maintaining proper chromatin structure, cell morphology, gene expression, stress resistance and ageing. Here, we present our studies on the mtDNA copy number in Saccharomyces cerevisiae chromatin mutants and investigate the mitochondrial membrane potential throughout their lifespan. The mutants are arp4 (with a point mutation in the ARP4 gene, coding for actin-related protein 4-Arp4p), hho1Δ (lacking the HHO1 gene, coding for the linker histone H1), and the double mutant arp4 hho1Δ cells with the two mutations. Our findings showed that the three chromatin mutants acquired strain-specific changes in the mtDNA copy number. Furthermore, we detected the disrupted mitochondrial membrane potential in their chronological lifespan. In addition, the expression of nuclear genes responsible for regulating mitochondria biogenesis and turnover was changed. The most pronounced were the alterations found in the double mutant arp4 hho1Δ strain, which appeared as the only petite colony-forming mutant, unable to grow on respiratory substrates and with partial depletion of the mitochondrial genome. The results suggest that in the studied chromatin mutants, hho1Δ, arp4 and arp4 hho1Δ, the nucleus-mitochondria communication was disrupted, leading to impaired mitochondrial function and premature ageing phenotype in these mutants, especially in the double mutant.

19.
Dalton Trans ; 52(35): 12282-12295, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37574873

RESUMO

Two families of homo- and heterometallic complexes, [Zn2L1(µ-OH)(H2O)2](ClO4)2, [Zn2L2(µ-OH)(H2O)2](ClO4)2, [Zn2L3(µ-OH)(H2O)2](ClO4)2, 1∞[{L1Zn2(µ-OH)}{µ-[Ag(CN)2]}](ClO4), [{L1Zn2(µ-OH)}2{µ-[Au(CN)2]}{[Au(CN)2]2}](ClO4)·H2O, 1∞[{L2Zn2(µ3-OH)}2(H2O){µ-[Ag(CN)2]}](ClO4)3·THF·0.5MeOH, 1∞[{L2Zn2(µ3-OH)}2(H2O){µ-[Au(CN)2]}](ClO4)3·THF·H2O, and 1∞[{L3Zn2(µ-OH)}{µ-[Ag(CN)2]}][Ag(CN)2]·H2O, respectively, have been synthesized and characterized. The Schiff bases used as ligands were obtained by condensation reactions of 2,6-diformyl-p-cresol with N,N-dimethyl-ethylenediamine (HL1), 2-aminomethyl-pyridine (HL2), and 2-aminoethyl-pyridine (HL3), respectively. The cytotoxic/cytostatic and genotoxic effects in cultured human MCF-7 (luminal type A breast cancer), MDA-MB-231 (triple negative breast cancer), HeLa (cervical carcinoma), and Lep-3 (non-tumor embryonal fibroblastoid cells) were studied. The investigations were performed by thiazolyl blue tetrazolium bromide test (MTT test), neutral red uptake cytotoxicity assay, crystal violet staining, hematoxylin and eosin staining, double staining with acridine orange and propidium iodide, AnnexinV/FITC, and Comet assay in short-term experiments (24-72 h, with monolayer cell cultures) as well as by 3D colony-forming method in long-term experiments (28 days, with 3D cancer cell colonies). The results obtained revealed that: (i) applied at a concentration range of 0.1-100 µg mL-1, the compounds investigated decrease in a time- and concentration-dependent manner the viability and/or proliferation of the treated cells; (ii) complexes of {Zn(II)Au(I)} show relatively higher cytotoxic/genotoxic activity and antitumor potential as compared to {Zn(II)Ag(I)}; (iii) some of the complexes demonstrate more pronounced cytotoxic potential than commercially available antitumor agents cisplatin, oxaliplatin, and epirubicin.


Assuntos
Antineoplásicos , Neoplasias de Mama Triplo Negativas , Humanos , Bases de Schiff/farmacologia , Bases de Schiff/química , Ligantes , Antineoplásicos/farmacologia , Antineoplásicos/química , Zinco/farmacologia , Zinco/química , Piridinas
20.
Pharmaceutics ; 14(6)2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35745786

RESUMO

Colorectal cancer (CRC) is a global health problem responsible for 10% of all cancer incidences and 9.4% of all cancer deaths worldwide. The number of new cases increases per annum, whereas the lack of effective therapies highlights the need for novel therapeutic approaches. Conventional treatment methods, such as surgery, chemotherapy and radiotherapy, are widely applied in oncology practice. Their therapeutic success is little, and therefore, the search for novel technologies is ongoing. Many efforts have focused recently on the development of safe and efficient cancer nanomedicines. Nanoparticles are among them. They are uniquewith their properties on a nanoscale and hold the potential to exploit intrinsic metabolic differences between cancer and healthy cells. This feature allows them to induce high levels of toxicity in cancer cells with little damage to the surrounding healthy tissues. Graphene oxide is a promising 2D material found to play an important role in cancer treatments through several strategies: direct killing and chemosensitization, drug and gene delivery, and phototherapy. Several new treatment approaches based on nanoparticles, particularly graphene oxide, are currently under research in clinical trials, and some have already been approved. Here, we provide an update on the recent advances in nanomaterials-based CRC-targeted therapy, with special attention to graphene oxide nanomaterials. We summarise the epidemiology, carcinogenesis, stages of the CRCs, and current nanomaterials-based therapeutic approaches for its treatment.

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