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1.
Mol Pharm ; 21(6): 2937-2948, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38750625

RESUMO

Polymers are extensively used for the realization of drug delivery systems across multiple scales, from nanomedicines to microparticles and macroscopic implantable devices, for their favorable biodegradation profiles and tunable physicochemical features. The accurate quantification of the polymer content is key to finely controlling drug loading and release and ensuring reproducibility, yet it continues to be a major challenge in the design and development of delivery systems. In this study, we introduce a novel protocol based on the PULCON technique to quantify, with a routine NMR spectroscopy analysis, the precise concentration of polymers in various delivery systems. Specifically, the PULCON protocol is applied to characterize the physicochemical and pharmaceutical properties of nanoparticles, microparticles, and implantable devices realized by combining three extensively used polymers, namely, poly(lactic-co-glycolic acid) (PLGA), poly(vinyl alcohol) (PVA), and poly(ethylene glycol) (PEG). Without using internal calibration procedures, in a single step, the PULCON protocol precisely quantifies the concentration of each polymer and the drug content. This approach can be readily implemented on standard NMR spectrometers, enabling accurate characterization of drug delivery systems and facilitating their effective development.


Assuntos
Sistemas de Liberação de Medicamentos , Espectroscopia de Ressonância Magnética , Polietilenoglicóis , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Espectroscopia de Ressonância Magnética/métodos , Sistemas de Liberação de Medicamentos/métodos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Polietilenoglicóis/química , Álcool de Polivinil/química , Polímeros/química , Nanopartículas/química , Liberação Controlada de Fármacos , Portadores de Fármacos/química , Tamanho da Partícula
2.
Ann Ig ; 35(2): 202-212, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35788249

RESUMO

Abstract: School Active Breaks are short bouts of physical activity (5-15 minutes) conducted by appropriately trained teachers and delivered during or between curricular lessons. They are a good strategy to counteract sedentary behaviors, and a growing body of evidence shows that they can represent also a tool to promote and improve health, school wellbeing and academic achievements. On 19 February 2022, the Working Group on Movement Sciences for Health of the Italian Society of Hygiene, Preventive Medicine and Public Health organized an Awareness Day on the effectiveness, usefulness and feasibility of School Active Breaks, opened to teachers, educators, school leaders, pediatricians, personnel from Departments of Prevention and Public Health and Health Policy-makers. During the event, the testimonies about the experiences already carried out in Italy showed that School Active Breaks are an effective intervention that each school can easily include in its educational offer and apply in any context.


Assuntos
Promoção da Saúde , Comportamento Sedentário , Humanos , Serviços de Saúde Escolar , Exercício Físico , Instituições Acadêmicas
3.
J Intellect Disabil Res ; 65(5): 464-488, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33719112

RESUMO

BACKGROUND: Classroom-based active breaks can help typically developing children reduce sitting, increase physical activity and improve cognitive functions and on-task behaviour. Yet, this strategy has not been tested in children with intellectual disability (ID) - a population who are insufficiently active. This study aimed to investigate the effects of a 5-week active breaks intervention on cognitive functions and on-task behaviour in schoolchildren with ID. METHODS: Twenty-four children, aged between 8 and 12 years (37.5% girls), were recruited. Children's cognitive functions (response inhibition, lapses of attention, interference and working memory) were measured at baseline and end of trial using computer-based tests. Sitting, standing and movement patterns were assessed with inclinometers, and on-task behaviour was directly observed in the classroom before and after active breaks, at baseline, mid-trial and end of trial. Linear mixed models were used to investigate the intervention effects on cognitive functions and sedentary patterns; generalised linear mixed models were used to analyse on-task behaviour data. RESULTS: A significant time × group interaction was found for working memory favouring the intervention (B = 11.56, 95% confidence interval [1.92, 21.21]). No significant effects were found in relation to the other measures of children's cognition or on-task behaviour. Stepping time and bouts of sitting were positively affected. CONCLUSIONS: Classroom-based active breaks can increase physical activity and reduce sedentary behaviour in children with ID and might also benefit their working memory. Further research is required to clarify the effects on cognition and to investigate whether this strategy has other benefits in this population.


Assuntos
Deficiência Intelectual , Criança , Cognição , Feminino , Humanos , Masculino , Projetos Piloto , Instituições Acadêmicas , Comportamento Sedentário
4.
Mol Syst Biol ; 14(4): e7390, 2018 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-29618636

RESUMO

Populations of isogenic cells often respond coherently to signals, despite differences in protein abundance and cell state. Previously, we uncovered processes in the Saccharomyces cerevisiae pheromone response system (PRS) that reduced cell-to-cell variability in signal strength and cellular response. Here, we screened 1,141 non-essential genes to identify 50 "variability genes". Most had distinct, separable effects on strength and variability of the PRS, defining these quantities as genetically distinct "axes" of system behavior. Three genes affected cytoplasmic microtubule function: BIM1, GIM2, and GIM4 We used genetic and chemical perturbations to show that, without microtubules, PRS output is reduced but variability is unaffected, while, when microtubules are present but their function is perturbed, output is sometimes lowered, but its variability is always high. The increased variability caused by microtubule perturbations required the PRS MAP kinase Fus3 and a process at or upstream of Ste5, the membrane-localized scaffold to which Fus3 must bind to be activated. Visualization of Ste5 localization dynamics demonstrated that perturbing microtubules destabilized Ste5 at the membrane signaling site. The fact that such microtubule perturbations cause aberrant fate and polarity decisions in mammals suggests that microtubule-dependent signal stabilization might also operate throughout metazoans.


Assuntos
Sistema de Sinalização das MAP Quinases/genética , Proteínas dos Microtúbulos/genética , Microtúbulos/genética , Análise de Célula Única , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas de Ciclo Celular/genética , Microtúbulos/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Feromônios/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Transdução de Sinais/genética
6.
Proc Natl Acad Sci U S A ; 109(10): 3874-8, 2012 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-22355134

RESUMO

Organismal fitness depends on the ability of gene networks to function robustly in the face of environmental and genetic perturbations. Understanding the mechanisms of this stability is one of the key aims of modern systems biology. Dissecting the basis of robustness to mutation has proven a particular challenge, with most experimental models relying on artificial DNA sequence variants engineered in the laboratory. In this work, we hypothesized that negative regulatory feedback could stabilize gene expression against the disruptions that arise from natural genetic variation. We screened yeast transcription factors for feedback and used the results to establish ROX1 (Repressor of hypOXia) as a model system for the study of feedback in circuit behaviors and its impact across genetically heterogeneous populations. Mutagenesis experiments revealed the mechanism of Rox1 as a direct transcriptional repressor at its own gene, enabling a regulatory program of rapid induction during environmental change that reached a plateau of moderate steady-state expression. Additionally, in a given environmental condition, Rox1 levels varied widely across genetically distinct strains; the ROX1 feedback loop regulated this variation, in that the range of expression levels across genetic backgrounds showed greater spread in ROX1 feedback mutants than among strains with the ROX1 feedback loop intact. Our findings indicate that the ROX1 feedback circuit is tuned to respond to perturbations arising from natural genetic variation in addition to its role in induction behavior. We suggest that regulatory feedback may be an important element of the network architectures that confer mutational robustness across biology.


Assuntos
Análise Mutacional de DNA , Proteínas Repressoras/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Biologia Computacional/métodos , Citometria de Fluxo , Genes Fúngicos , Variação Genética , Genômica , Proteínas de Fluorescência Verde/metabolismo , Hipóxia , Microscopia de Fluorescência/métodos , Modelos Genéticos , Fases de Leitura Aberta , Saccharomyces cerevisiae/metabolismo , Análise de Sequência de DNA , Fatores de Transcrição/metabolismo
7.
Metab Eng ; 25: 238-47, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25073011

RESUMO

D-xylonate is a potential platform chemical which can be produced by engineered Saccharomyces cerevisiae strains. In order to address production constraints in more detail, we analysed the role of lactone ring opening in single cells and populations. Both D-xylono-γ-lactone and D-xylonate were produced when the Caulobacter crescentus xylB (D-xylose dehydrogenase) was expressed in S. cerevisiae, with or without co-expression of xylC (D-xylonolactonase), as seen by (1)H NMR. XylC facilitated rapid opening of the lactone and more D-xylonate was initially produced than in its absence. Using in vivo(1)H NMR analysis of cell extracts, culture media and intact cells we observed that the lactone and linear forms of D-xylonic acid were produced, accumulated intracellularly, and partially exported within 15-60min of D-xylose provision. During single-cell analysis of cells expressing the pH sensitive fluorescent probe pHluorin, pHluorin fluorescence was gradually lost from the cells during D-xylonate production, as expected for cells with decreasing intracellular pH. However, in the presence of D-xylose, only 9% of cells expressing xylB lost pHluorin fluorescence within 4.5h, whereas 99% of cells co-expressing xylB and xylC lost fluorescence, a large proportion of which also lost vitality, during this interval. Loss of vitality in the presence of D-xylose was correlated to the extracellular pH, but fluorescence was lost from xylB and xylC expressing cells regardless of the extracellular condition.


Assuntos
Análise do Fluxo Metabólico/métodos , Modelos Biológicos , Saccharomyces cerevisiae/metabolismo , Açúcares Ácidos/metabolismo , Xilosidases/metabolismo , Simulação por Computador , Regulação Enzimológica da Expressão Gênica/fisiologia , Regulação Fúngica da Expressão Gênica/fisiologia , Transdução de Sinais/fisiologia
8.
Lupus ; 23(10): 1066-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24786782

RESUMO

Neuropsychiatric manifestations are serious and frequent complications of systemic lupus erythematous (SLE). Catatonia is a neuropsychiatric disorder characterized by motor disturbance (including waxy flexibility and catalepsy), stupor, excitement, negativism, mutism, echopraxia and echolalia. Catatonia associated with SLE has been only rarely reported, especially in children. Here we present a case of a 14-year-old patient encountered in consultation-liaison psychiatry who presented catatonia associated with SLE. Her catatonia was refractory to treatment with pulse methylprednisolone, intravenous cyclophosphamide and rituximab. The patient responded to a combined therapy of electroconvulsive therapy and benzodiazepines. The present case suggests that although rarely reported, catatonia seen in the background of SLE should be promptly identified and treated to reduce the morbidity.


Assuntos
Catatonia/terapia , Eletroconvulsoterapia , Vasculite Associada ao Lúpus do Sistema Nervoso Central/terapia , Adolescente , Benzodiazepinas/uso terapêutico , Catatonia/diagnóstico , Catatonia/etiologia , Catatonia/psicologia , Terapia Combinada , Feminino , Humanos , Vasculite Associada ao Lúpus do Sistema Nervoso Central/complicações , Vasculite Associada ao Lúpus do Sistema Nervoso Central/diagnóstico , Vasculite Associada ao Lúpus do Sistema Nervoso Central/psicologia , Resultado do Tratamento
9.
Nature ; 456(7223): 755-61, 2008 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-19079053

RESUMO

Haploid Saccharomyces cerevisiae yeast cells use a prototypic cell signalling system to transmit information about the extracellular concentration of mating pheromone secreted by potential mating partners. The ability of cells to respond distinguishably to different pheromone concentrations depends on how much information about pheromone concentration the system can transmit. Here we show that the mitogen-activated protein kinase Fus3 mediates fast-acting negative feedback that adjusts the dose response of the downstream system response to match the dose response of receptor-ligand binding. This 'dose-response alignment', defined by a linear relationship between receptor occupancy and downstream response, can improve the fidelity of information transmission by making downstream responses corresponding to different receptor occupancies more distinguishable and reducing amplification of stochastic noise during signal transmission. We also show that one target of the feedback is a previously uncharacterized signal-promoting function of the regulator of G-protein signalling protein Sst2. Our work suggests that negative feedback is a general mechanism used in signalling systems to align dose responses and thereby increase the fidelity of information transmission.


Assuntos
Retroalimentação Fisiológica/fisiologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Feromônios/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/fisiologia , Transdução de Sinais , Relação Dose-Resposta a Droga , Proteínas Ativadoras de GTPase/metabolismo , Feromônios/farmacologia , Ligação Proteica , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Transdução de Sinais/efeitos dos fármacos
10.
Appl Environ Microbiol ; 79(24): 7569-82, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24038690

RESUMO

Organic acids derived from engineered microbes can replace fossil-derived chemicals in many applications. Fungal hosts are preferred for organic acid production because they tolerate lignocellulosic hydrolysates and low pH, allowing economic production and recovery of the free acid. However, cell death caused by cytosolic acidification constrains productivity. Cytosolic acidification affects cells asynchronously, suggesting that there is an underlying cell-to-cell heterogeneity in acid productivity and/or in resistance to toxicity. We used fluorescence microscopy to investigate the relationship between enzyme concentration, cytosolic pH, and viability at the single-cell level in Saccharomyces cerevisiae engineered to synthesize xylonic acid. We found that cultures producing xylonic acid accumulate cells with cytosolic pH below 5 (referred to here as "acidified"). Using live-cell time courses, we found that the probability of acidification was related to the initial levels of xylose dehydrogenase and sharply increased from 0.2 to 0.8 with just a 60% increase in enzyme abundance (Hill coefficient, >6). This "switch-like" relationship likely results from an enzyme level threshold above which the produced acid overwhelms the cell's pH buffering capacity. Consistent with this hypothesis, we showed that expression of xylose dehydrogenase from a chromosomal locus yields ∼20 times fewer acidified cells and ∼2-fold more xylonic acid relative to expression of the enzyme from a plasmid with variable copy number. These results suggest that strategies that further reduce cell-to-cell heterogeneity in enzyme levels could result in additional gains in xylonic acid productivity. Our results demonstrate a generalizable approach that takes advantage of the cell-to-cell variation of a clonal population to uncover causal relationships in the toxicity of engineered pathways.


Assuntos
Ácidos Carboxílicos/metabolismo , Ácidos Carboxílicos/toxicidade , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/metabolismo , Desidrogenases de Carboidrato/metabolismo , Citosol/química , Concentração de Íons de Hidrogênio , Viabilidade Microbiana/efeitos dos fármacos , Microscopia de Fluorescência , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/efeitos dos fármacos
11.
Public Health ; 126(9): 740-8, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22769595

RESUMO

OBJECTIVES: Drug supply and demand indicators have mainly been analysed without triangulating information on environmental drug availability and consumption. This study proposes an approach to analyse the prevalence of illicit drug consumption together with indirect indicators of drug supply. STUDY DESIGN: Ecological study correlating cocaine seizure data and consumption prevalence estimates at local level, using Italian provinces as the unit of analysis. METHODS: The amount of cocaine seized in proportion to the number of potential consumers was computed at Italian provincial level from the 2005 database of the Italian Central Directorate for Anti-Drug Services. Indicators of consumption prevalence, at provincial level, in 15-16-year-old students from the 2005 European School Survey Project on Alcohol and Other Drugs (ESPAD) and 15-54-year-old respondents from the 2005 Italian Population Survey on Alcohol and Drugs (IPSAD) were correlated with the population-adjusted amount of total seizures and seizures of different sizes. ESPAD data were also regressed on seizure data after controlling for the prediction accrued by socio-economic variables that might cause covariation of seizure and consumption prevalence data. Regression-predicted prevalence values were computed and correlated with the ESPAD prevalence data for the following year. RESULTS: There was a weak general correlation between the population-adjusted total seizure and IPSAD prevalence indicators, but not ESPAD prevalence indicators. In contrast, ESPAD data were more strongly correlated with small seizures. The regression model yielded significant variance in prevalence data (18% and 23% in small and large provinces, respectively) explained by small seizures, and this remained after removing the percentage of variance explained by socio-economic factors and (particularly) education level. A moderate correlation was found between seizure-based predicted values of consumption prevalence and ESPAD values for the following year. CONCLUSIONS: Associating prevalence estimates in adolescents and cocaine seizure data at local level, after 'purifying' the data from trafficking- and wholesale-related large seizures, may represent a starting point for a geo-referenced, seizure-based analysis of initiation into cocaine consumption. This approach may support the collaboration between enforcement and health systems, helping to establish empirical regularities to be translated into useful information for local planners of drug prevention policies in areas at greater risk of increasing incidence.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/epidemiologia , Cocaína , Controle de Medicamentos e Entorpecentes/estatística & dados numéricos , Adolescente , Adulto , Coleta de Dados , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
12.
Nature ; 437(7059): 699-706, 2005 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-16170311

RESUMO

Here we studied the quantitative behaviour and cell-to-cell variability of a prototypical eukaryotic cell-fate decision system, the mating pheromone response pathway in yeast. We dissected and measured sources of variation in system output, analysing thousands of individual, genetically identical cells. Only a small proportion of total cell-to-cell variation is caused by random fluctuations in gene transcription and translation during the response ('expression noise'). Instead, variation is dominated by differences in the capacity of individual cells to transmit signals through the pathway ('pathway capacity') and to express proteins from genes ('expression capacity'). Cells with high expression capacity express proteins at a higher rate and increase in volume more rapidly. Our results identify two mechanisms that regulate cell-to-cell variation in pathway capacity. First, the MAP kinase Fus3 suppresses variation at high pheromone levels, while the MAP kinase Kss1 enhances variation at low pheromone levels. Second, pathway capacity and expression capacity are negatively correlated, suggesting a compensatory mechanism that allows cells to respond more precisely to pheromone in the presence of a large variation in expression capacity.


Assuntos
Linhagem da Célula , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/metabolismo , Transdução de Sinais , Proteína Quinase CDC28 de Saccharomyces cerevisiae/metabolismo , Ciclo Celular/fisiologia , Linhagem da Célula/efeitos dos fármacos , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Fator de Acasalamento , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Modelos Biológicos , Peptídeos/farmacologia , Feromônios/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Transdução de Sinais/efeitos dos fármacos , Processos Estocásticos
13.
Scand J Med Sci Sports ; 19(3): 412-8, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18466184

RESUMO

To assess whether an enrichment of the coordinative demands of physical education (PE) during the curricular time may more efficiently improve coordinative abilities than the traditional PE program. One hundred and fifty-two middle school students aged 11-12 years were randomly assigned either to an experimental (n=77) or to a traditional (n=75) PE program lasting 5 months. The experimental intervention was structured in different modules focused on co-ordination abilities. Pre- and post-intervention tests assessed students' fitness (1 mile run/walk, curl-up, flexed arm hang, trunk lift, sit and reach, 30 m run, standing long jump, basketball forward throw) and motor co-ordination abilities (four field tests of kinesthetic discrimination and response orientation ability). After the intervention period, both groups showed a significant increment in most fitness tests. However, only the experimental group showed a significant improvement or a significantly more pronounced improvement than the control group in coordinative performances. The results show that both experimental and traditional PE interventions lead to increase physical fitness levels, but only the experimental one also improves coordinative abilities. Thus, focusing on a multivariate PE approach linking co-ordination and fitness training seems to add quality to students' experiences without reducing their effectiveness in terms of physical fitness.


Assuntos
Educação Física e Treinamento/organização & administração , Aptidão Física/fisiologia , Desempenho Psicomotor/fisiologia , Criança , Currículo , Feminino , Humanos , Itália , Masculino , Avaliação de Programas e Projetos de Saúde
14.
J Clin Invest ; 93(5): 2251-7, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8182157

RESUMO

We have investigated the effects of cystamine on the replication of human immunodeficiency virus (HIV) in human lymphocytes and macrophages, the natural targets of HIV in vivo. Treatment of chronically infected macrophages with cystamine, at a concentration (500 microM) that did not show any cytotoxic or cytostatic effects, strongly decreased (> 80%) HIV-p24 antigen production and completely abolished the production of infectious viral particles. Cystamine does not affect viral transcription, translation or protein processing; indeed, all HIV proteins are present in a pattern similar to that of nontreated cells. Instead, cystamine interferes with the orderly assembly of HIV virions, as shown by electron microscopy analysis, that reveals only defective viral particles in treated cells. Moreover, suppression of HIV replication, due to the inhibition of proviral DNA formation was observed in acutely infected lymphocytes and macrophages pretreated with cystamine. These results show that cystamine potently suppresses HIV replication in human cells by contemporaneously blocking at least two independent steps of the viral life cycle, without affecting cell viability, suggesting that this compound may represent a new possibility towards the treatment of HIV-1 infection.


Assuntos
Antivirais/farmacologia , Cistamina/farmacologia , HIV/crescimento & desenvolvimento , Macrófagos/microbiologia , Células Cultivadas , Replicação do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , HIV/ultraestrutura , Proteína do Núcleo p24 do HIV/biossíntese , Humanos , Linfócitos/microbiologia , Macrófagos/ultraestrutura , Provírus/efeitos dos fármacos , Provírus/crescimento & desenvolvimento , Proteínas Virais/biossíntese , Replicação Viral/efeitos dos fármacos , Zidovudina/farmacologia
15.
J Nutr Health Aging ; 21(3): 284-291, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28244568

RESUMO

OBJECTIVE: To examine the relationship between regional and whole body fat accumulation and core cognitive executive functions. DESIGN: Cross-sectional study. SETTINGS AND PARTICIPANTS: 78 healthy men and women aged between 65 and 75 years recruited through consumer's database. MEASUREMENTS: DXA measured percentage total body fat, android, gynoid distribution and android/gynoid ratio; inhibition and working memory updating through Random Number Generation test and cognitive flexibility by Trail Making test. First-order partial correlations between regional body fat and cognitive executive function were computed partialling out the effects of whole body fat. Moderation analysis was performed to verify the effect of gender on the body fat-cognition relationship. RESULTS: Results showed a differentiated pattern of fat-cognition relationship depending on fat localization and type of cognitive function. Statistically significant relationships were observed between working memory updating and: android fat (r = -0.232; p = 0.042), gynoid fat (r = 0.333; p = 0.003) and android/gynoid ratio (r = -0.272; p = 0.017). Separating genders, the only significant relationship was observed in females between working memory updating and gynoid fat (r = 0.280; p = 0.045). In spite of gender differences in both working memory updating and gynoid body fat levels, moderation analysis did not show an effect of gender on the relationship between gynoid fat and working memory updating. CONCLUSIONS: Results suggest a protective effect of gynoid body fat and a deleterious effect of android body fat. Although excessive body fat increases the risk of developing CDV, metabolic and cognitive problems, maintaining a certain proportion of gynoid fat may help prevent cognitive decline, particularly in older women. Guidelines for optimal body composition maintenance for the elderly should not target indiscriminate weight loss, but weight maintenance through body fat/lean mass control based on non-pharmacological tools such as physical exercise, known to have protective effects against CVD risk factors and age-related cognitive deterioration.


Assuntos
Tecido Adiposo/metabolismo , Distribuição da Gordura Corporal , Cognição/fisiologia , Disfunção Cognitiva/fisiopatologia , Função Executiva/fisiologia , Obesidade/metabolismo , Absorciometria de Fóton/métodos , Idoso , Antropometria/métodos , Índice de Massa Corporal , Peso Corporal , Estudos Transversais , Exercício Físico , Feminino , Humanos , Masculino , Metiltestosterona/sangue , Fatores de Risco
16.
Sci Rep ; 7(1): 10157, 2017 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-28860643

RESUMO

The molecular details of local plant response against Xanthomonas translucens infection is largely unknown. Moreover, there is no knowledge about effects of the pathogen on the root's transcriptome and proteome. Therefore, we investigated the global gene and protein expression changes both in leaves and roots of wheat (Triticum aestivum) 24 h post leaf infection of X. translucens. This simultaneous analysis allowed us to obtain insight into possible metabolic rearrangements in above- and belowground tissues and to identify common responses as well as specific alterations. At the site of infection, we observed the implication of various components of the recognition, signaling, and amplification mechanisms in plant response to the pathogen. Moreover, data indicate a massive down-regulation of photosynthesis and confirm the chloroplast as crucial signaling hub during pathogen attack. Notably, roots responded as well to foliar attack and their response significantly differed from that locally triggered in infected leaves. Data indicate that roots as a site of energy production and synthesis of various secondary metabolites may actively influence the composition and colonisation level of root-associated microbes. Finally, our results emphasize the accumulation of jasmonic acid, pipecolic acid and/or the downstream mediator of hydrogen peroxide as long distal signals from infected leaves to roots.


Assuntos
Proteoma/genética , Transcriptoma , Triticum/genética , Xanthomonas/patogenicidade , Cloroplastos/metabolismo , Cloroplastos/microbiologia , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Ácidos Pipecólicos/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Proteoma/metabolismo , Triticum/microbiologia
17.
Cancer Res ; 61(22): 8171-8, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11719447

RESUMO

The thiol N-acetyl-L-cysteine (NAC), an analogue and precursor of reduced glutathione, has cancer chemopreventive properties attributable to its nucleophilicity, antioxidant activity, and a variety of other mechanisms. We demonstrated recently that NAC has anti-invasive, antimetastatic, and antiangiogenic effects in in vitro and in vivo test systems. In the present study, s.c. transplantation of KS-Imm cells in (CD-1)BR nude mice resulted in the local growth of Kaposi's sarcoma, a highly vascularized human tumor. The daily administration of NAC with drinking water, initiated after the tumor mass had become established and detectable, produced a sharp inhibition of tumor growth, with regression of tumors in half of the treated mice along with a markedly prolonged median survival time. The production of vascular endothelial growth factor (VEGF) and certain proliferation markers (proliferating cell nuclear antigen and Ki-67) were significantly lower in Kaposi's sarcomas from NAC-treated mice than from control mice. Treatment of KS-Imm cells with NAC in vitro resulted in a dose-dependent inhibition of chemotaxis and invasion through inhibition of gelatinase-A (matrix metalloproteinase-2, MMP-2) activity without altering MMP-2 or MMP-9 mRNA levels. NAC also significantly inhibited VEGF production but did not affect proliferation markers in vitro. Reverse transcription-PCR analysis indicated that total VEGF mRNAs were reduced by 10 mM NAC. Taken together, these findings provide evidence that NAC, the safety of which even at high doses has been established in almost 40 years of clinical use, in addition to its chemopreventive action, has a strong antiangiogenic potential that could be exploited for preventing cancer progression as well as used in cancer adjuvant therapy.


Assuntos
Acetilcisteína/farmacologia , Inibidores da Angiogênese/farmacologia , Neovascularização Patológica/tratamento farmacológico , Sarcoma de Kaposi/irrigação sanguínea , Administração Oral , Animais , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Movimento Celular/efeitos dos fármacos , Fatores de Crescimento Endotelial/antagonistas & inibidores , Fatores de Crescimento Endotelial/biossíntese , Fatores de Crescimento Endotelial/genética , Feminino , Inibidores do Crescimento/farmacologia , Humanos , Antígeno Ki-67/metabolismo , Linfocinas/antagonistas & inibidores , Linfocinas/biossíntese , Linfocinas/genética , Masculino , Camundongos , Camundongos Nus , Antígeno Nuclear de Célula em Proliferação/metabolismo , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Sarcoma de Kaposi/patologia , Células Tumorais Cultivadas , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Biomed Res Int ; 2016: 5812092, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28053985

RESUMO

Physical and cognitive training seem to counteract age-related decline in physical and mental function. Recently, the possibility of integrating cognitive demands into physical training has attracted attention. The purpose of this study was to evaluate the effects of twelve weeks of designed physical-cognitive training on executive cognitive function and gait performance in older adults. Thirty-six healthy, active individuals aged 72.30 ± 5.84 years were assigned to two types of physical training with major focus on physical single task (ST) training (n = 16) and physical-cognitive dual task (DT) training (n = 20), respectively. They were tested before and after the intervention for executive function (inhibition, working memory) through Random Number Generation and for gait (walking with/without negotiating hurdles) under both single and dual task (ST, DT) conditions. Gait performance improved in both groups, while inhibitory performance decreased after exercise training with ST focus but tended to increase after training with physical-cognitive DT focus. Changes in inhibition performance were correlated with changes in DT walking performance with group differences as a function of motor task complexity (with/without hurdling). The study supports the effectiveness of group exercise classes for older individuals to improve gait performance, with physical-cognitive DT training selectively counteracting the age-related decline in a core executive function essential for daily living.


Assuntos
Acidentes por Quedas/prevenção & controle , Terapia por Exercício , Marcha/fisiologia , Caminhada/fisiologia , Idoso , Idoso de 80 Anos ou mais , Atenção/fisiologia , Feminino , Humanos , Masculino , Equilíbrio Postural/fisiologia , Desempenho Psicomotor
19.
Diabetes ; 46(7): 1198-206, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9200656

RESUMO

In this study, we investigated 1) whether long-term restoration of euglycemia by means of pancreatic islet transplants is capable of preventing and/or reversing renal functional and structural alterations in an experimental model of insulin-deficient diabetes, and 2) whether changes in extracellular matrix (ECM) and cell turnover at the glomerular level and biochemical abnormalities associated with hyperglycemia correlate with the renal outcome after transplantation. Male Lewis rats, rendered diabetic by intravenous injection of streptozotocin, underwent homologous islet transplantation via the portal vein at 2 weeks (study A), at 4 months (study B), and at 8 months (study C) after the induction of diabetes and killed 12 months after transplantation in study A and 4 months after transplantation in studies B and C. Age-matched nondiabetic and untreated diabetic rats were used as control animals and were studied at 4, 8, and 12 months. In the untreated diabetic animals, metabolic derangement was associated with increased erythrocyte polyol and fructose levels, tail-tendon content of advanced glycation end products (AGEs), total proteinuria, albuminuria, kidney weight, and mean glomerular volume as well as with marked glomerular and extraglomerular lesions. Glomerular gene expression for the ECM components fibronectin and collagen IV and for TGF-beta was also increased, whereas glomerular cell proliferation was unaffected by diabetes. In study A, changes in renal function and structure observed in diabetic rats at 12 months were completely prevented by successful islet transplants. In study B, all functional and structural abnormalities detected in diabetic rats at 4 months of disease duration were virtually reversed by 4 months of euglycemia in transplanted animals, whereas they progressed further in untreated diabetic rats. In study C, the course of functional and structural changes observed in untreated diabetic rats was not reversed by islet transplantation. Likewise, tissue AGE accumulation and particularly upregulation of glomerular ECM and transforming growth factor (TGF)-beta gene expression, which are believed to play a role in the pathogenesis of altered renal function and structure in diabetes, were normalized in transplanted rats from study A and study B, but not in those from study C. These experiments show that restoration of euglycemia by islet transplants is capable of preventing experimental diabetic glomerulopathy and reversing early changes in renal function and structure induced by diabetes. In a later phase of the disease, when glomerular matrix gene expression becomes independent of hyperglycemia, possibly because of the persistent increase in tissue AGE accumulation, metabolic control is not capable of reversing renal abnormalities.


Assuntos
Diabetes Mellitus Experimental/complicações , Nefropatias Diabéticas/cirurgia , Proteínas da Matriz Extracelular/genética , Expressão Gênica/genética , Transplante das Ilhotas Pancreáticas , Glomérulos Renais/fisiopatologia , Animais , Estudos de Coortes , Colágeno/análise , Colágeno/genética , Colágeno/metabolismo , Creatinina/sangue , Creatinina/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Diabetes Mellitus Experimental/prevenção & controle , Modelos Animais de Doenças , Proteínas da Matriz Extracelular/análise , Proteínas da Matriz Extracelular/metabolismo , Fibronectinas/análise , Fibronectinas/genética , Fibronectinas/metabolismo , Glomérulos Renais/metabolismo , Glomérulos Renais/ultraestrutura , Masculino , Estudos Prospectivos , Proteinúria/metabolismo , Proteinúria/urina , RNA Mensageiro/análise , RNA Mensageiro/genética , Distribuição Aleatória , Ratos , Ratos Endogâmicos Lew , Fatores de Tempo , Fator de Crescimento Transformador beta/análise , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo
20.
Neuroscience ; 298: 211-9, 2015 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-25907444

RESUMO

The association between a fit body and a fit brain in children has led to a rise of behavioral and neuroscientific research. Yet, the relation of cardiorespiratory fitness on premotor neurocognitive preparation with early visual processing has received little attention. Here, 41 healthy, lower and higher fit preadolescent children were administered a modified version of the Eriksen flanker task while electroencephalography (EEG) and behavioral measures were recorded. Event-related potentials (ERPs) locked to the stimulus onset with an earlier than usual baseline (-900/-800 ms) allowed investigation of both the usual post-stimulus (i.e., the P1, N1 and P2) as well as the pre-stimulus ERP components, such as the Bereitschaftspotential (BP) and the prefrontal negativity (pN component). At the behavioral level, aerobic fitness was associated response accuracy, with higher fit children being more accurate than lower fit children. Fitness-related differences selectively emerged at prefrontal brain regions during response preparation, with larger pN amplitude for higher than lower fit children, and at early perceptual stages after stimulus onset, with larger P1 and N1 amplitudes in higher relative to lower fit children. Collectively, the results suggest that the benefits of being aerobically fit appear at the stage of cognitive preparation prior to stimulus presentation and the behavioral response during the performance of a task that challenges cognitive control. Further, it is likely that enhanced activity in prefrontal brain areas may improve cognitive control of visuo-motor tasks, allowing for stronger proactive inhibition and larger early allocation of selective attention resources on relevant external stimuli.


Assuntos
Cognição/fisiologia , Potenciais Evocados Visuais/fisiologia , Subunidade beta do Hormônio Folículoestimulante/fisiologia , Intenção , Aptidão Física/fisiologia , Precursores de Proteínas/fisiologia , Percepção Visual/fisiologia , Análise de Variância , Mapeamento Encefálico , Criança , Eletroencefalografia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Estimulação Luminosa , Tempo de Reação
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