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4.
Phys Rev Lett ; 131(5): 052503, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37595241

RESUMO

Potassium-40 is a widespread, naturally occurring isotope whose radioactivity impacts subatomic rare-event searches, nuclear structure theory, and estimated geological ages. A predicted electron-capture decay directly to the ground state of argon-40 has never been observed. The KDK (potassium decay) collaboration reports strong evidence of this rare decay mode. A blinded analysis reveals a nonzero ratio of intensities of ground-state electron-captures (I_{EC^{0}}) over excited-state ones (I_{EC^{*}}) of I_{EC^{0}}/I_{EC^{*}}=0.0095±[over stat]0.0022±[over sys]0.0010 (68% C.L.), with the null hypothesis rejected at 4σ. In terms of branching ratio, this signal yields I_{EC^{0}}=0.098%±[over stat]0.023%±[over sys]0.010%, roughly half of the commonly used prediction, with consequences for various fields [27L. Hariasz et al., companion paper, Phys. Rev. C 108, 014327 (2023)PRVCAN2469-998510.1103/PhysRevC.108.014327].

5.
Int J Mol Sci ; 23(24)2022 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-36555741

RESUMO

This work aims to improve the corrosion protection features of poly(phenylene methylene) (PPM) by sidechain engineering inserting methoxy units along the polymer backbone. The influence of side methoxy groups at different concentrations (4.6% mol/mol and 9% mol/mol) on the final polymer properties was investigated by structural and thermal characterization of the resulting copolymers: co-PPM 4.6% and co-PPM 9%, respectively. Then, coatings were processed by hot pressing the polymers powder on aluminum alloy AA2024 and corrosion protection properties were evaluated exposing samples to a 3.5% w/v NaCl aqueous solution. Anodic polarization tests evidenced the enhanced corrosion protection ability (i.e., lower current density) by increasing the percentage of the co-monomer. Coatings made with co-PPM 9% showed the best protection performance with respect to both PPM blend and PPM co-polymers reported so far. Electrochemical response of aluminum alloy coated with co-PPM 9% was monitored over time under two "artificially-aged" conditions, that are: (i) a pristine coating subjected to potentiostatic anodic polarization cycles, and (ii) an artificially damaged coating at resting condition. The first scenario points to accelerating the corrosion process, the second one models damage of the coating potentially occurring either due to natural deterioration or due to any accidental scratching of the polymer layer. In both cases, an intrinsic self-healing phenomenon was indirectly argued by the time evolution of the impedance and of the current density of the coated systems. The degree of restoring to the "factory conditions" by co-polymer coatings after self-healing events is eventually discussed.


Assuntos
Alumínio , Materiais Revestidos Biocompatíveis , Corrosão , Materiais Revestidos Biocompatíveis/química , Ligas/química , Polímeros
6.
Polymers (Basel) ; 14(17)2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36080534

RESUMO

Poly(phenylene methylene) (PPM) is a multifunctional polymer featuring hydrophobicity, high thermal stability, fluorescence and thermoplastic processability. Accordingly, smart corrosion resistant PPM-based coatings (blend and copolymer) were prepared and applied by hot pressing on aluminum alloy AA2024. The corrosion protection properties of the coatings and their dependence on coating thickness were evaluated for both strategies employed. The accelerated cyclic electrochemical technique (ACET), based on a combination of electrochemical impedance spectroscopy (EIS), cathodic polarizations and relaxation steps, was used as the main investigating technique. At the coating thickness of about 50 µm, both blend and copolymer PPM showed effective corrosion protection, as reflected by |Z|0.01Hz of about 108 Ω cm2 over all the ACET cycles. In contrast, when the coating thickness was reduced to 30 µm, PPM copolymer showed neatly better corrosion resistance than blended PPM, maintaining |Z|0.01Hz above 108 Ω cm2 with respect to values below 106 Ω cm2 of the latter. Furthermore, the analysis of many electrochemical key features, in combination with the optical investigation of the coating surface under 254 nm UV light, confirms the intrinsic self-healing ability of the coatings made by PPM copolymer, contrary to the reference specimen (i.e., blend PPM).

7.
Bioorg Chem ; 127: 106000, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35853296

RESUMO

In the last decade, emerging evidence has shown that low molecular weight protein tyrosine phosphatase (LMWPTP) not only contributes to the progression of cancer but is associated with prostate low survival rate and colorectal cancer metastasis. We report that LMWPTP favors the glycolytic profile in some tumors. Therefore, the focus of the present study was to identify metabolic enzymes that correlate with LMWPTP expression in patient samples. Exploratory data analysis from RNA-seq, proteomics, and histology staining, confirmed the higher expression of LMWPTP in CRC. Our descriptive statistical analyses indicate a positive expression correlation between LMWPTP and energy metabolism enzymes such as acetyl-CoA carboxylase (ACC) and fatty acid synthase (FASN). In addition, we examine the potential of violacein to reprogram energetic metabolism and LMWPTP activity. Violacein treatment induced a shift of glycolytic to oxidative metabolism associated with alteration in mitochondrial efficiency, as indicated by higher oxygen consumption rate. Particularly, violacein treated cells displayed higher proton leak and ATP-linked oxygen consumption rate (OCR) as an indicator of the OXPHOS preference. Notably, violacein is able to bind and inhibit LMWPTP. Since the LMWPTP acts as a hub of signaling pathways that offer tumor cells invasive advantages, such as survival and the ability to migrate, our findings highlight an unexplored potential of violacein in circumventing the metabolic plasticity of tumor cells.


Assuntos
Neoplasias Colorretais , Proteínas Tirosina Fosfatases , Neoplasias Colorretais/patologia , Humanos , Indóis , Masculino , Mitocôndrias/metabolismo , Peso Molecular , Proteínas Tirosina Fosfatases/metabolismo , Tirosina
8.
J Cell Biochem ; 123(7): 1247-1258, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35661241

RESUMO

Violacein is a secondary metabolite produced by several microorganisms including Chromobacterium violaceum, and it is already used in food and cosmetics. However, due to its potent anticancer and low side effects, its molecular action needs to be deeply scrutinized. Therefore, the main objective of this study was to evaluate the violacein's ability to interfere with three cancer hallmarks: growth factors receptor-dependent signaling, proliferation, and epithelial-mesenchymal transition (EMT). Violacein has been associated with the induction of apoptosis in colorectal cancer (CRC) cells. Here, we demonstrate that this molecule is also active in CRC spheroids and inhibits cell migration. Violacein treatment reduced the amount of EGFR and AXL receptors in the HT29 cell line. Accordingly, the inhibition of the AKT, ERK, and PKCδ kinases, which are downstream mediators of the signaling pathways triggered by EGFR and AXL, is detected. Another interesting finding was that even when the cells were stimulated with transforming growth factor-ß, the EMT marker (N-cadherin) decreased. Therefore, this study provides further evidence that reinforces the potential of violacein as an antitumor agent, once this biomolecule can "switch off" properties associated with cancer plasticity.


Assuntos
Neoplasias Colorretais , Transição Epitelial-Mesenquimal , Linhagem Celular Tumoral , Movimento Celular , Neoplasias Colorretais/metabolismo , Receptores ErbB , Humanos , Indóis/farmacologia
9.
An Acad Bras Cienc ; 94(2): e20200561, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35703689

RESUMO

Regular exercise is beneficial to health. This study evaluated the effects of moderate and intense physical exercise modalities on intradermal infection by Staphylococcus aureus in a murine model. Mice that practiced moderate exercise had lower bacterial load on lymph nodes and less inflammatory infiltrate in dermis. They presented greater weight, however, less amount of epididymal fat: the weight was increased while they had fat diminished. A positive correlation was observed between lipid content and bacterial load in mice trained at moderate intensity. Animals that were under high intensity exercises presented superior bacterial load on the lymph nodes, increased neutrophil count and circulating lymphocytes, and had leukocyte recruitment to the dermis augmented, when compared to the ones in moderate exercise. These findings suggest that moderate physical activity modulates the immune response in dermal infection caused by S. aureus in a murine model.


Assuntos
Infecções Estafilocócicas , Staphylococcus aureus , Animais , Carga Bacteriana , Modelos Animais de Doenças , Camundongos , Projetos Piloto
11.
Vet Rec Open ; 9(1): e26, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35127102

RESUMO

BACKGROUND: A 7.8-kb deletion in intron 4 of the NHEJ1 canine gene is associated with Collie Eye Anomaly (CEA). This deletion has been described in sheep-herding breeds related to the collie lineage and in several other dog breeds. A genetic test based on this association can distinguish three genotypes: normal, carrier and affected. The present study is a retrospective investigation of the presence of the CEA allele frequencies in selected breeds from the Italian dog population over a 10-year time span. METHODS: Genotype data, for the 7.8 kb deletion in intron 4 of the NHEJ1 gene, from 496 dogs belonging to Border collie (BC, n = 334), Shetland Sheepdog (SS, n = 74), Australian Shepherd (AS, n = 52), Nova Scotia Duck Tolling Retriever (NS, n = 20) and Rough Collie (RC, n = 16) were analysed. The genetic frequency of CEA allele was estimated in breeds with higher observations (BC, SS and AS). RESULTS: Healthy carriers were 50%, 45%, 29.6%, 17.3% and 12.5% in SS, NS, BC, AS and RC, respectively. The affected recessive homozygotes were 81.3%, 10.8% and 1.5% in RC, SS and BC, respectively. The CEA allelic frequencies were 0.36, 0.16 and 0.087 in SS, BC and AS, respectively. CONCLUSION: The results support the usefulness of this type of genetic analysis to optimize the care of dogs where the CEA mutation is present, including assessing the health risk to susceptible dogs within a breed and to provide an objective basis for breeding programmes.

12.
Phys Rev Lett ; 128(1): 011801, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35061499

RESUMO

Dark matter with Planck-scale mass (≃10^{19} GeV/c^{2}) arises in well-motivated theories and could be produced by several cosmological mechanisms. A search for multiscatter signals from supermassive dark matter was performed with a blind analysis of data collected over a 813 d live time with DEAP-3600, a 3.3 t single-phase liquid argon-based detector at SNOLAB. No candidate signals were observed, leading to the first direct detection constraints on Planck-scale mass dark matter. Leading limits constrain dark matter masses between 8.3×10^{6} and 1.2×10^{19} GeV/c^{2}, and ^{40}Ar-scattering cross sections between 1.0×10^{-23} and 2.4×10^{-18} cm^{2}. These results are interpreted as constraints on composite dark matter models with two different nucleon-to-nuclear cross section scalings.

13.
Eur Phys J C Part Fields ; 81(9): 823, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34720726

RESUMO

The DEAP-3600 detector searches for the scintillation signal from dark matter particles scattering on a 3.3 tonne liquid argon target. The largest background comes from 39 Ar beta decays and is suppressed using pulse-shape discrimination (PSD). We use two types of PSD estimator: the prompt-fraction, which considers the fraction of the scintillation signal in a narrow and a wide time window around the event peak, and the log-likelihood-ratio, which compares the observed photon arrival times to a signal and a background model. We furthermore use two algorithms to determine the number of photons detected at a given time: (1) simply dividing the charge of each PMT pulse by the mean single-photoelectron charge, and (2) a likelihood analysis that considers the probability to detect a certain number of photons at a given time, based on a model for the scintillation pulse shape and for afterpulsing in the light detectors. The prompt-fraction performs approximately as well as the log-likelihood-ratio PSD algorithm if the photon detection times are not biased by detector effects. We explain this result using a model for the information carried by scintillation photons as a function of the time when they are detected.

15.
Mol Cell Biochem ; 466(1-2): 83-89, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32016696

RESUMO

In the last decade, several reports highlight the importance of the low molecular weight protein tyrosine phosphatase (LMWPTP) in cancer aggressiveness and resistance. Specifically, in chronic myeloid leukemia, we have reported that high expression of the LMWPTP maintains Src and Bcr-Abl kinases in an activated status and the glucose metabolism is directed to lactate production and, in turn, favor the pentoses pathway (one of the key process for antioxidant and protective responses). In this present study, we investigated the possible correlation between the LMWPTP and autophagy. In resistant chronic myeloid leukemia cells, the antioxidant response is supported by the glycolytic metabolism and antioxidant enzymes such as SOD and catalase, both favored by the LMWPTP. Therefore, when the cells were challenged by hydrogen peroxide treatment, the LMWPTP level goes down as well as SOD, and in turn, autophagy process was stimulated. The findings presented here reveal a novel aspect by which LMWPTP cooperates for the resistance of CML towards stressor stimuli.


Assuntos
Antioxidantes/metabolismo , Autofagia , Leucemia Mielogênica Crônica BCR-ABL Positiva/enzimologia , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia
16.
Reprod Domest Anim ; 55 Suppl 2: 4-9, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31913541

RESUMO

Pedigree dogs and cats are bred aiming to conform breed standards with very poor consideration for breeding stock fertility. At the same time, the genetic asset underlining reproductive traits could be effectively analysed like in other species under selection. The definition of selection targets is very important in breeding protocols determination. The aim of the present work is to present an overview of the different correlations between reproduction and genetics, starting from selection procedure and inbreeding coefficient moving to genomic and the application of SNPs and GWAS on population study and identification of genes involved in phenotypical variation of reproductive traits in dogs. Particular relevance has been given to the concept of inbreeding which effects on canine reproduction have been presented. The use of genomic information in inbreeding coefficient calculation can be considered an improved effective procedure in the evaluation of the genetic variability loss in canine population and its negative effects on reproductive traits.


Assuntos
Cruzamento/métodos , Cães/genética , Fertilidade/genética , Animais , Peso ao Nascer , Cesárea/veterinária , Feminino , Endogamia , Masculino , Reprodução/genética , Seleção Genética
17.
Neuroimage Clin ; 28: 102467, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33395963

RESUMO

Epileptic networks, defined as brain regions involved in epileptic brain activity, have been mapped by functional connectivity in simultaneous electroencephalography and functional magnetic resonance imaging (EEG-fMRI) recordings. This technique allows to define brain hemodynamic changes, measured by the Blood Oxygen Level Dependent (BOLD) signal, associated to the interictal epileptic discharges (IED), which together with ictal events constitute a signature of epileptic disease. Given the highly time-varying nature of epileptic activity, a dynamic functional connectivity (dFC) analysis of EEG-fMRI data appears particularly suitable, having the potential to identify transitory features of specific connections in epileptic networks. In the present study, we propose a novel method, defined dFC-EEG, that integrates dFC assessed by fMRI with the information recorded by simultaneous scalp EEG, in order to identify the connections characterised by a dynamic profile correlated with the occurrence of IED, forming the dynamic epileptic subnetwork. Ten patients with drug-resistant focal epilepsy were included, with different aetiology and showing a widespread (or multilobar) BOLD activation, defined as involving at least two distinct clusters, located in two different lobes and/or extended to the hemisphere contralateral to the epileptic focus. The epileptic focus was defined from the IED-related BOLD map. Regions involved in the occurrence of interictal epileptic activity; i.e., forming the epileptic network, were identified by a general linear model considering the timecourse of the fMRI-defined focus as main regressor. dFC between these regions was assessed with a sliding-window approach. dFC timecourses were then correlated with the sliding-window variance of the IED signal (VarIED), to identify connections whose dynamics related to the epileptic activity; i.e., the dynamic epileptic subnetwork. As expected, given the very different clinical picture of each individual, the extent of this subnetwork was highly variable across patients, but was but was reduced of at least 30% with respect to the initially identified epileptic network in 9/10 patients. The connections of the dynamic subnetwork were most commonly close to the epileptic focus, as reflected by the laterality index of the subnetwork connections, reported higher than the one within the original epileptic network. Moreover, the correlation between dFC timecourses and VarIED was predominantly positive, suggesting a strengthening of the dynamic subnetwork associated to the occurrence of IED. The integration of dFC and scalp IED offers a more specific description of the epileptic network, identifying connections strongly influenced by IED. These findings could be relevant in the pre-surgical evaluation for the resection or disconnection of the epileptogenic zone and help in reaching a better post-surgical outcome. This would be particularly important for patients characterised by a widespread pathological brain activity which challenges the surgical intervention.


Assuntos
Epilepsia , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Eletroencefalografia , Epilepsia/diagnóstico por imagem , Humanos
18.
Eur Urol Focus ; 6(2): 397-403, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30316824

RESUMO

BACKGROUND: A remote interaction between a console surgeon (CS) and a bedside surgeon (BS) makes the role of the latter critical. No conclusive data are reported about the length of the learning curve of a BS. OBJECTIVE: To highlight the role of a BS during robot-assisted radical prostatectomy (RARP) and to analyze the effect of the learning curve of a BS on intra- and postoperative outcomes. DESIGN, SETTING, AND PARTICIPANTS: From June 2013 to September 2016, 129 RARPs were performed by one expert CS (>1000 RARPs) and two BSs (residents). According to the learning curve of the BS, the patients were divided into three groups: group 1 (first 20 procedures), group 2 (21-40 procedures), and group 3 (>40 procedures). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Preoperative variables, pathological data, operating time (OT), blood loss (BL), number of lymph nodes excised (LE), length of hospital stay (LHS), and time to catheter removal (CR) were analyzed. Linear/logistic regression analyses tested the impact of BS experience on surgical outcomes. T test and chi-square test compared the outcomes of the two BSs. RESULTS AND LIMITATIONS: Perfect interaction between CSs and BSs are requested to obtain the optimal exposure and avoid any conflict. On the linear regression model, BS learning curve was not related to OT, BL, LHS, and CR, but was related to LE (r2=0.09; p=0.03). On multivariate analyses, no correlation between BS experience and OT, BL, LHS, CR, LE, margin status, and complications (all p>0.05) was found. Comparing the two BSs, no difference was found for the abovementioned outcomes in the first 40 surgeries (all p>0.05). Study limitations include the limited cohort of patients and its retrospective nature. CONCLUSIONS: In this study, BS learning curve does not appear to influence the surgical outcomes; good experience of the CS was probably the explanation. PATIENT SUMMARY: In our experience, it is the primary surgeon who dictates the perioperative outcomes during robot-assisted radical prostatectomy.


Assuntos
Curva de Aprendizado , Prostatectomia/educação , Prostatectomia/métodos , Procedimentos Cirúrgicos Robóticos/educação , Idoso , Humanos , Pessoa de Meia-Idade , Papel do Médico , Estudos Retrospectivos , Resultado do Tratamento , Urologia
19.
Clin Neurophysiol ; 130(12): 2193-2202, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31669753

RESUMO

OBJECTIVE: Epilepsy is a network disease with epileptic activity and cognitive impairment involving large-scale brain networks. A complex network is involved in the seizure and in the interictal epileptiform discharges (IEDs). Directed connectivity analysis, describing the information transfer between brain regions, and graph analysis are applied to high-density EEG to characterise networks. METHODS: We analysed 19 patients with focal epilepsy who had high-density EEG containing IED and underwent surgery. We estimated cortical activity during IED using electric source analysis in 72 atlas-based cortical regions of the individual brain MRI. We applied directed connectivity analysis (information Partial Directed Coherence) and graph analysis on these sources and compared patients with good vs poor post-operative outcome at global, hemispheric and lobar level. RESULTS: We found lower network integration reflected by global, hemispheric, lobar efficiency during the IED (p < 0.05) in patients with good post-surgical outcome, compared to patients with poor outcome. Prediction was better than using the IED field or the localisation obtained by electric source imaging. CONCLUSIONS: Abnormal network patterns in epilepsy are related to seizure outcome after surgery. SIGNIFICANCE: Our finding may help understand networks related to a more "isolated" epileptic activity, limiting the extent of the epileptic network in patients with subsequent good post-operative outcome.


Assuntos
Excitabilidade Cortical , Epilepsia do Lobo Temporal/fisiopatologia , Complicações Pós-Operatórias/fisiopatologia , Adolescente , Adulto , Criança , Eletroencefalografia/métodos , Epilepsia do Lobo Temporal/cirurgia , Feminino , Humanos , Masculino , Procedimentos Neurocirúrgicos/efeitos adversos
20.
Exp Gerontol ; 127: 110734, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31518664

RESUMO

In women, aging is evidenced by physiological hormonal alterations that trigger changes in body composition, emergence of chronic low-grade inflammation, which is an important pre-disposition to the development of chronic diseases such as Systemic Arterial Hypertension (SAH) and Type 2 Diabetes Mellitus (T2DM). Although it is a strong pro-inflammatory nature disorder, little is known about how body composition interferes with inflammatory markers in diabetic and hypertensive elderly women. Therefore, this study's objective was to evaluate the inflammation in diabetic and hypertensive elderly women, and their association with fat mass. It comprised the evaluation of 144 women aged between 60 and 80 years old, diagnosed with SAH and T2DM, assisted by Family Health Units in Vitória da Conquista, Bahia, Brazil. According to body mass index (BMI), these women were classified as either eutrophic or overweight. In the eutrophic females, the IL-10 / IL-17A ratio was increased when compared to those overweight. In addition, IL-17 correlated negatively with HDL and positively with total cholesterol, LDL, triglycerides, VLDL, and glucose in the eutrophic ones, but not in the overweight individuals. IL-10 also showed differences in the correlation pattern observed between the groups, since for this eutrophic cytokine, it presented positive correlation with the waist circumference, waist/height ratio, and negative association with IL-17, while in overweight elderly women, it was not observed such pattern. Hence, this work demonstrates how the amount of fat mass interferes with the balance of cytokines, especially IL-10 and IL-17, and how it may exert an effect on biochemical parameters and risk factors associated with T2DM and SAH.


Assuntos
Composição Corporal/fisiologia , Diabetes Mellitus Tipo 2/etiologia , Hipertensão/etiologia , Interleucina-10/metabolismo , Interleucina-17/metabolismo , Tecido Adiposo/fisiologia , Idoso , Idoso de 80 Anos ou mais , Pressão Arterial/fisiologia , Biomarcadores/metabolismo , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Humanos , Hipertensão/fisiopatologia , Inflamação/fisiopatologia , Pessoa de Meia-Idade , Sobrepeso/fisiopatologia , Fatores de Risco , Circunferência da Cintura/fisiologia
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