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1.
Chemistry ; 30(10): e202302940, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38078547

RESUMO

Aggregation-Induced Emission (AIE) luminogens have garnered significant interest due to their distinctive applications in different applications. Among the diverse molecular architectures, those based on triphenylamine and thiophene hold prominence. However, a comprehensive understanding of the deactivation mechanism both in solution and films remains lacking. In this study, we synthesized and characterized spectroscopically two AIE luminogens: 5-(4-(bis(4-methoxyphenyl)amino)phenyl)thiophene-2-carbaldehyde (TTY) and 5'-(4-(bis(4-methoxyphenyl)amino)phenyl)-[2,2'-bithiophene]-5-carbaldehyde (TTO). Photophysical and theoretical analyses were conducted in both solution and PMMA films to understand the deactivation mechanism of TTY and TTO. In diluted solutions, the emission behavior of TTY and TTO is influenced by the solvent, and the deactivation of the excited state can occur via locally excited (LE) or twisted intramolecular charge transfer (TICT) state. In PMMA films, rotational and translational movements are constrained, necessitating emission solely from the LE state. Nevertheless, in the PMMA film, excimers-like structures form, resulting in the emergence of a longer wavelength band and a reduction in emission intensity. The zenith of emission intensity occurs when molecules are dispersed at higher concentrations within PMMA, effectively diminishing the likelihood of excimer-like formations. Luminescent Solar Concentrators (LSC) were fabricated to validate these findings, and the optical efficiency was studied at varying concentrations of luminogen and PMMA.

2.
Cell Rep ; 42(12): 113516, 2023 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-38048225

RESUMO

The immune checkpoint NKG2A/CD94 is a promising target for cancer immunotherapy, and its ligand major histocompatibility complex E (MHC-E) is frequently upregulated in cancer. NKG2A/CD94-mediated inhibition of lymphocytes depends on the presence of specific leader peptides in MHC-E, but when and where they are presented in situ is unknown. We apply a nanobody specific for the Qdm/Qa-1b complex, the NKG2A/CD94 ligand in mouse, and find that presentation of Qdm peptide depends on every member of the endoplasmic reticulum-resident peptide loading complex. With a turnover rate of 30 min, the Qdm peptide reflects antigen processing capacity in real time. Remarkably, Qdm/Qa-1b complexes require inflammatory signals for surface expression in situ, despite the broad presence of Qa-1b molecules in homeostasis. Furthermore, we identify LILRB1 as a functional inhibition receptor for MHC-E in steady state. These data provide a molecular understanding of NKG2A blockade in immunotherapy and assign MHC-E as a convergent ligand for multiple immune checkpoints.


Assuntos
Antígenos de Histocompatibilidade Classe I , Neoplasias , Camundongos , Animais , Antígenos de Histocompatibilidade Classe I/metabolismo , Receptor B1 de Leucócitos Semelhante a Imunoglobulina/metabolismo , Células Matadoras Naturais , Ligantes , Peptídeos/metabolismo , Neoplasias/metabolismo , Subfamília C de Receptores Semelhantes a Lectina de Células NK/metabolismo
3.
Comput Struct Biotechnol J ; 21: 1759-1773, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36915380

RESUMO

Human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs) are commonly used to model arrhythmogenic cardiomyopathy (ACM), a heritable cardiac disease characterized by severe ventricular arrhythmias, fibrofatty myocardial replacement and progressive ventricular dysfunction. Although ACM is inherited as an autosomal dominant disease, incomplete penetrance and variable expressivity are extremely common, resulting in different clinical manifestations. Here, we propose hiPSC-CMs as a powerful in vitro model to study incomplete penetrance in ACM. Six hiPSC lines were generated from blood samples of three ACM patients carrying a heterozygous deletion of exon 4 in the PKP2 gene, two asymptomatic (ASY) carriers of the same mutation and one healthy control (CTR), all belonging to the same family. Whole exome sequencing was performed in all family members and hiPSC-CMs were examined by ddPCR, western blot, Wes™ immunoassay system, patch clamp, immunofluorescence and RNASeq. Our results show molecular and functional differences between ACM and ASY hiPSC-CMs, including a higher amount of mutated PKP2 mRNA, a lower expression of the connexin-43 protein, a lower overall density of sodium current, a higher intracellular lipid accumulation and sarcomere disorganization in ACM compared to ASY hiPSC-CMs. Differentially expressed genes were also found, supporting a predisposition for a fatty phenotype in ACM hiPSC-CMs. These data indicate that hiPSC-CMs are a suitable model to study incomplete penetrance in ACM.

4.
Life Sci Alliance ; 4(8)2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34187875

RESUMO

The oncogenic role of common fragile sites (CFS), focal and pervasive gaps in the cancer genome arising from replicative stress, remains controversial. Exploiting the TCGA dataset, we found that in most CFS the genes residing within the associated focal deletions are down-regulated, including proteins involved in tumour immune recognition. In a subset of CFS, however, the residing genes are surprisingly overexpressed. Within the most frequent CFS in this group, FRA4F, which is deleted in up to 18% of cancer cases and harbours the CCSER1 gene, we identified a region which includes an intronic, antisense pseudogene, TMSB4XP8. TMSB4XP8 focal ablation or transcriptional silencing elicits the overexpression of CCSER1, through a cis-acting mechanism. CCSER1 overexpression increases proliferation and triggers centrosome amplifications, multinuclearity, and aberrant mitoses. Accordingly, FRA4F is associated in patient samples to mitotic genes deregulation and genomic instability. As a result, cells overexpressing CCSER1 become sensitive to the treatment with aurora kinase inhibitors. Our findings point to a novel tumourigenic mechanism where focal deletions increase the expression of a new class of "dormant" oncogenes.


Assuntos
Proteínas de Ciclo Celular/genética , Sítios Frágeis do Cromossomo , Deleção de Genes , Regulação para Cima , Linhagem Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Instabilidade Genômica , Células HEK293 , Células HeLa , Humanos , Mitose , Pseudogenes
5.
Molecules ; 25(1)2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31878329

RESUMO

The development of high performance optically pumped organic lasers operating in the deep blue still remains a big challenge. In this paper, we have investigated the photophysics and the optical gain characteristics of a novel fluorene oligomer functionalized by four triphenylamine (TPA) groups. By ultrafast spectroscopy we found a large gain spectral region from 420 to 500 nm with a maximum gain cross-section of 1.5 × 10-16 cm2 which makes this molecule a good candidate for photonic applications. Amplified Spontaneous Emission measurements (ASE) under 150 fs and 3 ns pump pulses have revealed a narrow emission at 450 nm with a threshold of 5.5 µJcm-2 and 21 µJcm-2 respectively. Our results evidence that this new fluorene molecule is an interesting material for photonic applications, indeed the inclusion of TPA as a lateral substituent leads to a high gain and consequently to a low threshold blue organic ASE.


Assuntos
Compostos de Anilina/química , Fluorenos/química , Luz , Luminescência , Sondas Moleculares/química , Fatores de Tempo
6.
J Transl Med ; 17(1): 408, 2019 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-31801616

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is characterized by triglyceride accumulation in the hepatocytes in the absence of alcohol overconsumption, commonly associated with insulin resistance and obesity. Both NAFLD and type 2 diabetes (T2D) are characterized by an altered microbiota composition, however the role of the microbiota in NAFLD and T2D is not well understood. To assess the relationship between alteration in the microbiota and NAFLD while dissecting the role of T2D, we established a nested study on T2D and non-T2D individuals within the Cooperative Health Research In South Tyrol (CHRIS) study, called the CHRIS-NAFLD study. Here, we present the study protocol along with baseline and follow-up characteristics of study participants. METHODS: Among the first 4979 CHRIS study participants, 227 individuals with T2D were identified and recalled, along with 227 age- and sex-matched non-T2D individuals. Participants underwent ultrasound and transient elastography examination to evaluate the presence of hepatic steatosis and liver stiffness. Additionally, sampling of saliva and faeces, biochemical measurements and clinical interviews were carried out. RESULTS: We recruited 173 T2D and 183 non-T2D participants (78% overall response rate). Hepatic steatosis was more common in T2D (63.7%) than non-T2D (36.3%) participants. T2D participants also had higher levels of liver stiffness (median 4.8 kPa, interquartile range (IQR) 3.7, 5.9) than non-T2D participants (median 3.9 kPa, IQR 3.3, 5.1). The non-invasive scoring systems like the NAFLD fibrosis score (NFS) suggests an increased liver fibrosis in T2D (mean - 0.55, standard deviation, SD, 1.30) than non-T2D participants (mean - 1.30, SD, 1.17). DISCUSSION: Given the comprehensive biochemical and clinical characterization of study participants, once the bioinformatics classification of the microbiota will be completed, the CHRIS-NAFLD study will become a useful resource to further our understanding of the relationship between microbiota, T2D and NAFLD.


Assuntos
Diabetes Mellitus Tipo 2/microbiologia , Microbiota , Hepatopatia Gordurosa não Alcoólica/microbiologia , Idoso , Bactérias/metabolismo , Diabetes Mellitus Tipo 2/complicações , Feminino , Humanos , Masculino , Síndrome Metabólica/complicações , Hepatopatia Gordurosa não Alcoólica/complicações
7.
Int J Mol Sci ; 20(8)2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-31014028

RESUMO

In early diabetes, hyperglycemia and the associated metabolic dysregulation promote early changes in the functional properties of cardiomyocytes, progressively leading to the appearance of the diabetic cardiomyopathy phenotype. Recently, the interplay between histone acetyltransferases (HAT) and histone deacetylases (HDAC) has emerged as a crucial factor in the development of cardiac disorders. The present study evaluates whether HDAC inhibition can prevent the development of cardiomyocyte contractile dysfunction induced by a short period of hyperglycemia, with focus on the potential underlying mechanisms. Cell contractility and calcium dynamics were measured in unloaded ventricular myocytes isolated from the heart of control and diabetic rats. Cardiomyocytes were either untreated or exposed to the pan-HDAC inhibitor suberoylanilide hydroxamic acid (SAHA) for 90 min. Then, a fraction of each group of cells was used to evaluate the expression levels of proteins involved in the excitation-contraction coupling, and the cardiomyocyte metabolic activity, ATP content, and reactive oxygen species levels. SAHA treatment was able to counteract the initial functional derangement in cardiomyocytes by reducing cell oxidative damage. These findings suggest that early HDAC inhibition could be a promising adjuvant approach for preventing diabetes-induced cardiomyocyte oxidative damage, which triggers the pro-inflammatory signal cascade, mitochondrial damage, and ventricular dysfunction.


Assuntos
Inibidores de Histona Desacetilases/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Vorinostat/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Cálcio/metabolismo , Células Cultivadas , Diabetes Mellitus Experimental/patologia , Histona Desacetilases/química , Histona Desacetilases/metabolismo , Masculino , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
8.
Int J Mol Sci ; 19(2)2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-29385061

RESUMO

SERCA2a is the Ca2+ ATPase playing the major contribution in cardiomyocyte (CM) calcium removal. Its activity can be regulated by both modulatory proteins and several post-translational modifications. The aim of the present work was to investigate whether the function of SERCA2 can be modulated by treating CMs with the histone deacetylase (HDAC) inhibitor suberanilohydroxamic acid (SAHA). The incubation with SAHA (2.5 µM, 90 min) of CMs isolated from rat adult hearts resulted in an increase of SERCA2 acetylation level and improved ATPase activity. This was associated with a significant improvement of calcium transient recovery time and cell contractility. Previous reports have identified K464 as an acetylation site in human SERCA2. Mutants were generated where K464 was substituted with glutamine (Q) or arginine (R), mimicking constitutive acetylation or deacetylation, respectively. The K464Q mutation ameliorated ATPase activity and calcium transient recovery time, thus indicating that constitutive K464 acetylation has a positive impact on human SERCA2a (hSERCA2a) function. In conclusion, SAHA induced deacetylation inhibition had a positive impact on CM calcium handling, that, at least in part, was due to improved SERCA2 activity. This observation can provide the basis for the development of novel pharmacological approaches to ameliorate SERCA2 efficiency.


Assuntos
Ácidos Hidroxâmicos/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Processamento de Proteína Pós-Traducional , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Acetilação , Animais , Inibidores de Histona Desacetilases/farmacologia , Humanos , Masculino , Miócitos Cardíacos/enzimologia , Miócitos Cardíacos/metabolismo , Ratos , Ratos Wistar , Vorinostat
9.
Stem Cell Res ; 27: 25-29, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29304398

RESUMO

Caveolinopathies are a heterogeneous family of genetic pathologies arising from alterations of the caveolin-3 gene (CAV3), encoding for the isoform specifically constituting muscle caveolae. Here, by reprogramming peripheral blood mononuclear cells, we report the generation of induced pluripotent stem cells (iPSCs) from three patients carrying the ΔYTT deletion, T78K and W101C missense mutations in caveolin-3. iPSCs displayed normal karyotypes and all the features of pluripotent stem cells in terms of morphology, specific marker expression and ability to differentiate in vitro into the three germ layers. These lines thus represent a human cellular model to study the molecular basis of caveolinopathies. Resource table.


Assuntos
Caveolina 3/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Caveolina 3/genética , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Células Cultivadas , Reprogramação Celular/genética , Reprogramação Celular/fisiologia , Citometria de Fluxo , Humanos , Cariótipo , Mutação/genética , Mutação de Sentido Incorreto/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Mol Pharm ; 15(3): 861-870, 2018 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-29307184

RESUMO

Certain xenobiotics, such as paraquat, are sequestered into the lungs from the systemic circulation by the polyamine transporter system (PTS). The aim of this study was to investigate whether ion-pairing a drug (theophylline) with a PTS substrate (spermine) provides a means of using this active transport mechanism to target drug delivery to the lungs. Fourier transform infrared spectroscopy showed that two of the amine groups of spermine interact with C-N7 and C6═O of theophylline, leaving two free amines to interact with the PTS. In A549 cells, which possess a functional PTS (spermidine Km and Vmax, 0.6 ± 0.3 µM and 1.8 ± 0.3 pmol·min-1 per 105 cells, respectively), uptake of the theophylline-spermine ion-pair was increased 1.8-fold compared to free theophylline at 37 °C, but not at 4 °C. In an isolated perfused rat lung model (IPL) a 3.6-fold increase in lung theophylline concentration was observed after vascular administration of the ion-pair compared to free theophylline. Theophylline was cleared from the IPL with similar kinetics irrespective of whether it was delivered as the free drug or an ion-pair, although lung levels remained elevated after washout following delivery as an ion-pair. In vitro simulation of the theophylline-spermine break down demonstrated that a drop in pH from 9.6 to 7.4, such as that undergone by the ion-pair in biological matrices, induces rapid and almost complete dissociation of the ion-paired species. However, infusion of the ion-pair formulations via the vasculature provides almost immediate delivery to the pulmonary capillary bed permitting PTS-mediated active sequestering of ion-paired theophylline into the lungs.


Assuntos
Broncodilatadores/administração & dosagem , Proteínas de Transporte de Cátions/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Pulmão/metabolismo , Teofilina/administração & dosagem , Células A549 , Animais , Broncodilatadores/farmacocinética , Humanos , Concentração de Íons de Hidrogênio , Íons/química , Masculino , Poliaminas/metabolismo , Ratos , Ratos Wistar , Espermina/química , Espermina/metabolismo , Teofilina/farmacocinética , Distribuição Tecidual
11.
Macromol Rapid Commun ; 38(7)2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28195679

RESUMO

Low-bandgap near-infrared polymers are usually synthesized using the common donor-acceptor (D-A) approach. However, recently polymer chemists are introducing more complex chemical concepts for better fine tuning of their optoelectronic properties. Usually these studies are limited to one or two polymer examples in each case study so far, though. In this study, the dependence of optoelectronic and macroscopic (device performance) properties in a series of six new D-A1 -D-A2 low bandgap semiconducting polymers is reported for the first time. Correlation between the chemical structure of single-component polymer films and their optoelectronic properties has been achieved in terms of absorption maxima, optical bandgap, ionization potential, and electron affinity. Preliminary organic photovoltaic results based on blends of the D-A1 -D-A2 polymers as the electron donor mixed with the fullerene derivative [6,6]-phenyl-C71 -butyric acid methyl ester demonstrate power conversion efficiencies close to 4% with short-circuit current densities (J sc ) of around 11 mA cm-2 , high fill factors up to 0.70, and high open-circuit voltages (V oc s) of 0.70 V. All the devices are fabricated in an inverted architecture with the photoactive layer processed in air with doctor blade technique, showing the compatibility with roll-to-roll large-scale manufacturing processes.


Assuntos
Fontes de Energia Elétrica , Polímeros/química , Energia Solar , Estrutura Molecular , Polímeros/síntese química
12.
Stem Cells Int ; 2017: 8960236, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29434642

RESUMO

Genome-editing technology has emerged as a powerful method that enables the generation of genetically modified cells and organisms necessary to elucidate gene function and mechanisms of human diseases. The clustered regularly interspaced short palindromic repeats- (CRISPR-) associated 9 (Cas9) system has rapidly become one of the most popular approaches for genome editing in basic biomedical research over recent years because of its simplicity and adaptability. CRISPR/Cas9 genome editing has been used to correct DNA mutations ranging from a single base pair to large deletions in both in vitro and in vivo model systems. CRISPR/Cas9 has been used to increase the understanding of many aspects of cardiovascular disorders, including lipid metabolism, electrophysiology and genetic inheritance. The CRISPR/Cas9 technology has been proven to be effective in creating gene knockout (KO) or knockin in human cells and is particularly useful for editing induced pluripotent stem cells (iPSCs). Despite these progresses, some biological, technical, and ethical issues are limiting the therapeutic potential of genome editing in cardiovascular diseases. This review will focus on various applications of CRISPR/Cas9 genome editing in the cardiovascular field, for both disease research and the prospect of in vivo genome-editing therapies in the future.

13.
FASEB J ; 29(4): 1540-50, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25550469

RESUMO

Androgens have important cardiometabolic actions in males, but their metabolic role in females is unclear. To determine the physiologic androgen receptor (AR)-dependent actions of androgens on atherogenesis in female mice, we generated female AR-knockout (ARKO) mice on an atherosclerosis-prone apolipoprotein E (apoE)-deficient background. After 8 weeks on a high-fat diet, but not on a normal chow diet, atherosclerosis in aorta was increased in ARKO females (+59% vs. control apoE-deficient mice with intact AR gene). They also displayed increased body weight (+18%), body fat percentage (+62%), and hepatic triglyceride levels, reduced insulin sensitivity, and a marked atherogenic dyslipidemia (serum cholesterol, +52%). Differences in atherosclerosis, body weight, and lipid levels between ARKO and control mice were abolished in mice that were ovariectomized before puberty, consistent with a protective action of ovarian androgens mediated via the AR. Furthermore, the AR agonist dihydrotestosterone reduced atherosclerosis (-41%; thoracic aorta), subcutaneous fat mass (-44%), and cholesterol levels (-35%) in ovariectomized mice, reduced hepatocyte lipid accumulation in hepatoma cells in vitro, and regulated mRNA expression of hepatic genes pivotal for lipid homeostasis. In conclusion, we demonstrate that the AR protects against diet-induced atherosclerosis in female mice and propose that this is mediated by modulation of body composition and lipid metabolism.


Assuntos
Aterosclerose/prevenção & controle , Dislipidemias/prevenção & controle , Obesidade/prevenção & controle , Receptores Androgênicos/metabolismo , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Aterosclerose/etiologia , Aterosclerose/metabolismo , Colesterol/metabolismo , Dieta/efeitos adversos , Di-Hidrotestosterona/farmacologia , Dislipidemias/etiologia , Dislipidemias/metabolismo , Fígado Gorduroso/etiologia , Fígado Gorduroso/metabolismo , Fígado Gorduroso/prevenção & controle , Feminino , Resistência à Insulina , Metabolismo dos Lipídeos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/etiologia , Obesidade/metabolismo , Orquiectomia , Ovariectomia , Receptores Androgênicos/deficiência , Receptores Androgênicos/genética
14.
Biochim Biophys Acta ; 1841(4): 574-80, 2014 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-24369119

RESUMO

The patatin-like phospholipase domain containing 3 (PNPLA3, also called adiponutrin, ADPN) is a membrane-bound protein highly expressed in the liver. The genetic variant I148M (rs738409) was found to be associated with progression of chronic liver disease. We aimed to establish a protein purification protocol in a yeast system (Pichia pastoris) and to examine the human PNPLA3 enzymatic activity, substrate specificity and the I148M mutation effect. hPNPLA3 148I wild type and 148M mutant cDNA were cloned into P. pastoris expression vectors. Yeast cells were grown in 3L fermentors. PNPLA3 protein was purified from membrane fractions by Ni-affinity chromatography. Enzymatic activity was assessed using radiolabeled substrates. Both 148I wild type and 148M mutant proteins are localized to the membrane. The wild type protein shows a predominant lipase activity with mild lysophosphatidic acid acyl transferase activity (LPAAT) and the I148M mutation results in a loss of function of both these activities. Our data show that PNPLA3 has a predominant lipase activity and I148M mutation results in a loss of function.


Assuntos
Hidrolases/metabolismo , Lipase/metabolismo , Proteínas de Membrana/genética , Proteínas Recombinantes/genética , Clonagem Molecular , Humanos , Hidrolases/genética , Lipase/biossíntese , Lipase/genética , Lipase/isolamento & purificação , Fígado/enzimologia , Fígado/patologia , Proteínas de Membrana/biossíntese , Proteínas de Membrana/isolamento & purificação , Mutação , Pichia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Triglicerídeos/metabolismo
15.
Clin Physiol Funct Imaging ; 34(3): 230-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24112387

RESUMO

BACKGROUND: Heart rate variability (HRV) has been rarely applied in elite athletes prior to competition. The aim of this study was to examine the changes in HRV in elite female volleyball players before a stressful match during play offs and to evaluate the impact on sport-specific performance. METHODS: A short-term resting HRV analysis was applied right after the night sleep in ten female athletes 1 and 2 days prior to the match and the day of the competition. RESULTS: Approaching the decisive match, RR interval, resting heart rate (HR), pNN50, rMSDD and SD1 did not significantly vary. SD2 significantly increased in comparison with first-day measurement (P<0·05). HF% levels significantly decreased the prematch day and the match day (P<0·05); however, no significant changes in LF/HF% ratio were observed. A gradual increase in VLF% and in LnVLF was observed, with a significant difference between first-day and match-day measurements (P<0·01 and P<0·05, respectively). The number of positive receptions was inversely correlated with LF/HFms(2) ratio, with LF/HF% ratio (R = -0·98, P<0·05 for both) and with resting HR (R = -0·92, P<0·05). CONCLUSIONS: Elite female athletes practising team sports exhibit a slight change in HRV prior to a decisive competition, without a pronounced variation of the autonomic nervous system activity. A day-to-day HRV measurement could be a useful tool to evaluate the impact of a competition on the autonomic nervous system in athletes, also considering the relationship between sympathetic activity and athletic performance.


Assuntos
Desempenho Atlético , Sistema Nervoso Autônomo/fisiologia , Comportamento Competitivo , Frequência Cardíaca , Coração/inervação , Voleibol , Adulto , Feminino , Humanos , Fatores de Tempo , Adulto Jovem
16.
PLoS One ; 7(11): e48804, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23144979

RESUMO

BACKGROUND & AIMS: Hepatic iron accumulation due to altered trafficking is frequent in patients with nonalcoholic fatty liver disease (NAFLD), and is associated with more severe liver damage and hepatocellular carcinoma. The p.Ala736Val TMPRSS6 variant influences iron metabolism regulating the transcription of the hepatic hormone hepcidin, but its role in the pathogenesis of iron overload disorders is controversial. Aim of this study was to evaluate the whether the TMPRSS6 p.Ala736Val variant influences hepatic iron accumulation in a well-characterized series of Italian patients with histological NAFLD. METHODS: 216 patients with histological NAFLD. TMPRSS6 and HFE variants were assessed by allele specific PCR, liver histology by the NAFLD activity score and Perls' staining for iron. RESULTS: Homozygosity for the p.736Val allele previously linked to higher hepcidin did not influence transferrin saturation (TS), but was associated with lower hepatic iron stores (p = 0.01), and ferritin levels (median 223 IQR 102-449 vs. 308 IQR 141-618 ng/ml; p = 0.01). Homozygosity for TMPRSS6 p.736Val was nearly associated with lower ballooning (p = 0.05), reflecting hepatocellular damage related to oxidative stress. The influence of TMPRSS6 on hepatic iron accumulation was more marked in patients negative for HFE genotypes predisposing to iron overload (p.Cys282Tyr + and p.His63Asp +/+; p = 0.01), and the p.736Val variant was negatively associated with hepatic iron accumulation independently of age, gender, HFE genotype, and beta-thalassemia trait (OR 0.59, 0.39-0.88). CONCLUSIONS: The p.Ala736Val TMPRSS6 variant influences secondary hepatic iron accumulation in patients with NAFLD.


Assuntos
Fígado Gorduroso/genética , Sobrecarga de Ferro/genética , Proteínas de Membrana/genética , Polimorfismo Genético , Serina Endopeptidases/genética , Substituição de Aminoácidos , Índice de Massa Corporal , Dislipidemias/complicações , Dislipidemias/genética , Fígado Gorduroso/complicações , Ferritinas/metabolismo , Predisposição Genética para Doença , Genótipo , Proteína da Hemocromatose , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Ferro/metabolismo , Sobrecarga de Ferro/complicações , Proteínas de Membrana/química , Hepatopatia Gordurosa não Alcoólica , Fatores de Risco , Serina Endopeptidases/química
17.
Yeast ; 23(11): 833-40, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16921555

RESUMO

[URE3] is an infectious (prion) inactive amyloid form of Ure2p, a regulator of nitrogen catabolism. [URE3] clones are selected on NH(4) (+), using their derepressed expression of DAL5 to allow uptake of ureidosuccinate (USA). We previously reported that mks1Delta prevents generation of [URE3] and others reported that glutamate in the medium or the elevated glutamate in mks1Delta strains blocks [URE3] generation. We show here that elevated glutamate does not block [URE3] generation, but that neither does mks1Delta. Rather, a post-transcriptional effect on DAL5 of mks1Delta through the retrograde regulation pathway prevents detection of [URE3] prion-containing colonies. Moreover, the presence of both ammonia and glutamate blocks USA uptake in a known [URE3] strain, so that detection of the prion is prevented, rather than its generation.


Assuntos
Nitrogênio/metabolismo , Príons/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Ácido Glutâmico/metabolismo , Glutationa Peroxidase , Ácidos Cetoglutáricos/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Compostos de Amônio Quaternário/metabolismo , Proteínas Repressoras/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Uracila/metabolismo
18.
Am Heart J ; 142(4): 633-40, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11579353

RESUMO

BACKGROUND: Pathogens causing chronic infections may promote atherosclerosis. The aim of our study was to evaluate the association of Chlamydia pneumoniae (Cp) and cytomegalovirus (CMV) infection and of inflammatory activation with premature myocardial infarction (MI). METHODS: Specific anti-Cp and anti-CMV immunoglobulin G (IgG), fibrinogen, white blood cells (WBC), and C-reactive protein (CRP) were measured in 120 post-MI patients

Assuntos
Infecções por Chlamydia/complicações , Chlamydophila pneumoniae/imunologia , Infecções por Citomegalovirus/complicações , Citomegalovirus/imunologia , Infarto do Miocárdio/etiologia , Adulto , Idade de Início , Anticorpos Antibacterianos/análise , Anticorpos Antivirais/análise , Biomarcadores , Proteína C-Reativa/análise , Infecções por Chlamydia/imunologia , Infecções por Citomegalovirus/imunologia , Feminino , Fibrinogênio/análise , Humanos , Imunoglobulina G/análise , Inflamação/diagnóstico , Inflamação/imunologia , Leucócitos/imunologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/imunologia , Fatores de Risco , Testes Sorológicos
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