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1.
Meat Sci ; 214: 109523, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38692013

RESUMO

Salt content standardization in dry-cured ham production is complex as there are many factors that influence salt uptake. The aim of this work was to study and model salt uptake as a function of salting time and the characteristics of green ham in two different ham types using a large amount of data obtained from an inline non-invasive characterization technology. The usefulness of these models to standardize the salt content of the industrial production was also evaluated. Magnetic induction technology was used to characterize lean and fatty hams in order to further model the salt uptake using different statistical methods. Salt content increased with the salting time showing an asymptotic behaviour which was lower in fatty hams. The best models were those that considered the salting time, weight, and fat content of hams as model independent variables. These models are helpful for salt content standardization within the industry and can be used to simulate process modifications and avoid the time-consuming and costly trial and error tests.


Assuntos
Manipulação de Alimentos , Produtos da Carne , Cloreto de Sódio na Dieta , Animais , Produtos da Carne/análise , Produtos da Carne/normas , Cloreto de Sódio na Dieta/análise , Manipulação de Alimentos/métodos , Suínos
2.
Phys Rev Lett ; 131(2): 022501, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37505957

RESUMO

The ß decays from both the ground state and a long-lived isomer of ^{133}In were studied at the ISOLDE Decay Station (IDS). With a hybrid detection system sensitive to ß, γ, and neutron spectroscopy, the comparative partial half-lives (logft) have been measured for all their dominant ß-decay channels for the first time, including a low-energy Gamow-Teller transition and several first-forbidden (FF) transitions. Uniquely for such a heavy neutron-rich nucleus, their ß decays selectively populate only a few isolated neutron unbound states in ^{133}Sn. Precise energy and branching-ratio measurements of those resonances allow us to benchmark ß-decay theories at an unprecedented level in this region of the nuclear chart. The results show good agreement with the newly developed large-scale shell model (LSSM) calculations. The experimental findings establish an archetype for the ß decay of neutron-rich nuclei southeast of ^{132}Sn and will serve as a guide for future theoretical development aiming to describe accurately the key ß decays in the rapid-neutron capture (r-) process.

3.
Phys Rev Lett ; 130(12): 122502, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37027859

RESUMO

The excited states of N=44 ^{74}Zn were investigated via γ-ray spectroscopy following ^{74}Cu ß decay. By exploiting γ-γ angular correlation analysis, the 2_{2}^{+}, 3_{1}^{+}, 0_{2}^{+}, and 2_{3}^{+} states in ^{74}Zn were firmly established. The γ-ray branching and E2/M1 mixing ratios for transitions deexciting the 2_{2}^{+}, 3_{1}^{+}, and 2_{3}^{+} states were measured, allowing for the extraction of relative B(E2) values. In particular, the 2_{3}^{+}→0_{2}^{+} and 2_{3}^{+}→4_{1}^{+} transitions were observed for the first time. The results show excellent agreement with new microscopic large-scale shell-model calculations, and are discussed in terms of underlying shapes, as well as the role of neutron excitations across the N=40 gap. Enhanced axial shape asymmetry (triaxiality) is suggested to characterize ^{74}Zn in its ground state. Furthermore, an excited K=0 band with a significantly larger softness in its shape is identified. A shore of the N=40 "island of inversion" appears to manifest above Z=26, previously thought as its northern limit in the chart of the nuclides.

4.
EMBO J ; 42(11): e111901, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36917141

RESUMO

Changes in mitochondrial morphology are associated with nutrient utilization, but the precise causalities and the underlying mechanisms remain unknown. Here, using cellular models representing a wide variety of mitochondrial shapes, we show a strong linear correlation between mitochondrial fragmentation and increased fatty acid oxidation (FAO) rates. Forced mitochondrial elongation following MFN2 over-expression or DRP1 depletion diminishes FAO, while forced fragmentation upon knockdown or knockout of MFN2 augments FAO as evident from respirometry and metabolic tracing. Remarkably, the genetic induction of fragmentation phenocopies distinct cell type-specific biological functions of enhanced FAO. These include stimulation of gluconeogenesis in hepatocytes, induction of insulin secretion in islet ß-cells exposed to fatty acids, and survival of FAO-dependent lymphoma subtypes. We find that fragmentation increases long-chain but not short-chain FAO, identifying carnitine O-palmitoyltransferase 1 (CPT1) as the downstream effector of mitochondrial morphology in regulation of FAO. Mechanistically, we determined that fragmentation reduces malonyl-CoA inhibition of CPT1, while elongation increases CPT1 sensitivity to malonyl-CoA inhibition. Overall, these findings underscore a physiologic role for fragmentation as a mechanism whereby cellular fuel preference and FAO capacity are determined.


Assuntos
Ácidos Graxos , Malonil Coenzima A , Ácidos Graxos/metabolismo , Malonil Coenzima A/metabolismo , Malonil Coenzima A/farmacologia , Carnitina O-Palmitoiltransferase/genética , Carnitina O-Palmitoiltransferase/metabolismo , Oxirredução , Mitocôndrias/metabolismo
5.
Phys Rev Lett ; 128(11): 112501, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35363028

RESUMO

Using the fusion-evaporation reaction ^{96}Ru(^{58}Ni,p4n)^{149}Lu and the MARA vacuum-mode recoil separator, a new proton-emitting isotope ^{149}Lu has been identified. The measured decay Q value of 1920(20) keV is the highest measured for a ground-state proton decay, and it naturally leads to the shortest directly measured half-life of 450_{-100}^{+170} ns for a ground-state proton emitter. The decay rate is consistent with l_{p}=5 emission, suggesting a dominant πh_{11/2} component for the wave function of the proton-emitting state. Through nonadiabatic quasiparticle calculations it was concluded that ^{149}Lu is the most oblate deformed proton emitter observed to date.

6.
Int J Pharm ; 616: 121554, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35131355

RESUMO

The high rate of HIV new infections and AIDS-related deaths each year make prevention tools still necessary today. Different dosage forms - including films - for vaginal administration of antiretroviral drugs have been developed for this purpose. Six batches of Tenofovir-loaded films were formulated based on Eudragit® L100 (EL100) and chitosan, containing triethyl citrate and glycerol. In all the cases films structured in two layers - the upper layer mainly attributed to EL100 and the lower layer to chitosan - were revealed by SEM. A higher content in EL100 and plasticizers improves the mechanical properties and control over drug release in the vaginal medium without affecting mucoadhesion. The EL100-based layer acts as a structuring agent that controls Tenofovir release for days in the vaginal medium while it occurs in a few hours in the presence of seminal fluid. Bilayer films with the highest tested content of EL100 and plasticizers would be the most suitable as vaginal microbicides as they are easier to administer due to their excellent mechanical properties and they offer more comfortable posology and enhanced protection against HIV during intercourse due to their pH-responsive release of Tenofovir.


Assuntos
Quitosana , Administração Intravaginal , Feminino , Humanos , Concentração de Íons de Hidrogênio , Ácidos Polimetacrílicos , Tenofovir
7.
Meat Sci ; 172: 108334, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33059180

RESUMO

The end of the elaboration process of dry-cured ham is currently decided by product weight loss and/or by an expert who carries out an evaluation of the tactile texture on the surface. The objective of this study was to define the optimal measurement conditions of an instrumental texture analysis on the surface of the dry-cured ham (ITAS), to define the end of process. 120 dry-cured hams were classified by experts into Hard (appropriate) or Soft (non-appropriate) texture groups and used to perform compression tests using different probes on three anatomical positions. Results showed that the small probe in position 2 gave the most discriminant conditions, providing representative information of the internal texture. Although classification using only weight loss was possible with an accuracy rate of 80.4% or 66.7% depending on the weight loss, the maximum classification accuracy was obtained when using ITAS in combination with weight loss. Further studies at industrial level are needed.


Assuntos
Manipulação de Alimentos/instrumentação , Produtos da Carne/análise , Animais , Manipulação de Alimentos/métodos , Conservação de Alimentos/métodos , Produtos da Carne/normas , Músculo Esquelético , Cloreto de Sódio/análise , Sus scrofa , Tomografia Computadorizada por Raios X
10.
Phys Rev Lett ; 124(4): 042503, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32058764

RESUMO

There is sparse direct experimental evidence that atomic nuclei can exhibit stable "pear" shapes arising from strong octupole correlations. In order to investigate the nature of octupole collectivity in radium isotopes, electric octupole (E3) matrix elements have been determined for transitions in ^{222,228}Ra nuclei using the method of sub-barrier, multistep Coulomb excitation. Beams of the radioactive radium isotopes were provided by the HIE-ISOLDE facility at CERN. The observed pattern of E3 matrix elements for different nuclear transitions is explained by describing ^{222}Ra as pear shaped with stable octupole deformation, while ^{228}Ra behaves like an octupole vibrator.

11.
Nat Immunol ; 20(12): 1668-1680, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31636464

RESUMO

Lymph node fibroblastic reticular cells (FRCs) respond to signals from activated T cells by releasing nitric oxide, which inhibits T cell proliferation and restricts the size of the expanding T cell pool. Whether interactions with FRCs also support the function or differentiation of activated CD8+ T cells is not known. Here we report that encounters with FRCs enhanced cytokine production and remodeled chromatin accessibility in newly activated CD8+ T cells via interleukin-6. These epigenetic changes facilitated metabolic reprogramming and amplified the activity of pro-survival pathways through differential transcription factor activity. Accordingly, FRC conditioning significantly enhanced the persistence of virus-specific CD8+ T cells in vivo and augmented their differentiation into tissue-resident memory T cells. Our study demonstrates that FRCs play a role beyond restricting T cell expansion-they can also shape the fate and function of CD8+ T cells.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Fibroblastos/fisiologia , Linfonodos/imunologia , Animais , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Reprogramação Celular , Montagem e Desmontagem da Cromatina , Citotoxicidade Imunológica , Epigênese Genética , Regulação da Expressão Gênica , Memória Imunológica , Interleucina-6/genética , Interleucina-6/metabolismo , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico/metabolismo
12.
Nat Commun ; 10(1): 2473, 2019 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-31171788

RESUMO

There is a large body of evidence that atomic nuclei can undergo octupole distortion and assume the shape of a pear. This phenomenon is important for measurements of electric-dipole moments of atoms, which would indicate CP violation and hence probe physics beyond the Standard Model of particle physics. Isotopes of both radon and radium have been identified as candidates for such measurements. Here, we observed the low-lying quantum states in 224Rn and 226Rn by accelerating beams of these radioactive nuclei. We show that radon isotopes undergo octupole vibrations but do not possess static pear-shapes in their ground states. We conclude that radon atoms provide less favourable conditions for the enhancement of a measurable atomic electric-dipole moment.

13.
Phys Rev Lett ; 121(25): 252501, 2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30608829

RESUMO

The first 2^{+} and 3^{-} states of the doubly magic nucleus ^{132}Sn are populated via safe Coulomb excitation employing the recently commissioned HIE-ISOLDE accelerator at CERN in conjunction with the highly efficient MINIBALL array. The ^{132}Sn ions are accelerated to an energy of 5.49 MeV/nucleon and impinged on a ^{206}Pb target. Deexciting γ rays from the low-lying excited states of the target and the projectile are recorded in coincidence with scattered particles. The reduced transition strengths are determined for the transitions 0_{g.s.}^{+}→2_{1}^{+}, 0_{g.s.}^{+}→3_{1}^{-}, and 2_{1}^{+}→3_{1}^{-} in ^{132}Sn. The results on these states provide crucial information on cross-shell configurations which are determined within large-scale shell-model and Monte Carlo shell-model calculations as well as from random-phase approximation and relativistic random-phase approximation. The locally enhanced B(E2;0_{g.s.}^{+}→2_{1}^{+}) strength is consistent with the microscopic description of the structure of the respective states within all theoretical approaches. The presented results of experiment and theory can be considered to be the first direct verification of the sphericity and double magicity of ^{132}Sn.

14.
Cell Death Differ ; 24(2): 251-262, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27768122

RESUMO

Diffuse large B-cell lymphomas (DLBCLs) are a highly heterogeneous group of tumors in which subsets share molecular features revealed by gene expression profiles and metabolic fingerprints. While B-cell receptor (BCR)-dependent DLBCLs are glycolytic, OxPhos-DLBCLs rely on mitochondrial energy transduction and nutrient utilization pathways that provide pro-survival benefits independent of BCR signaling. Integral to these metabolic distinctions is elevated mitochondrial electron transport chain (ETC) activity in OxPhos-DLBCLs compared with BCR-DLBCLs, which is linked to greater protein abundance of ETC components. To gain insights into molecular determinants of the selective increase in ETC activity and dependence on mitochondrial energy metabolism in OxPhos-DLBCLs, we examined the mitochondrial translation pathway in charge of the synthesis of mitochondrial DNA encoded ETC subunits. Quantitative mass spectrometry identified increased expression of mitochondrial translation factors in OxPhos-DLBCL as compared with the BCR subtype. Biochemical and functional assays indicate that the mitochondrial translation pathway is required for increased ETC activity and mitochondrial energy reserves in OxPhos-DLBCL. Importantly, molecular depletion of several mitochondrial translation proteins using RNA interference or pharmacological perturbation of the mitochondrial translation pathway with the FDA-approved inhibitor tigecycline (Tigecyl) is selectively toxic to OxPhos-DLBCL cell lines and primary tumors. These findings provide additional molecular insights into the metabolic characteristics of OxPhos-DLBCLs, and mark the mitochondrial translation pathway as a potential therapeutic target in these tumors.


Assuntos
Mitocôndrias/metabolismo , Acetilcisteína/farmacologia , Motivos de Aminoácidos , Antibacterianos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Complexo de Proteínas da Cadeia de Transporte de Elétrons/genética , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Humanos , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Mitocôndrias/efeitos dos fármacos , Proteínas Mitocondriais/antagonistas & inibidores , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Fosforilação Oxidativa/efeitos dos fármacos , Fator G para Elongação de Peptídeos/antagonistas & inibidores , Fator G para Elongação de Peptídeos/genética , Fator G para Elongação de Peptídeos/metabolismo , Fator Tu de Elongação de Peptídeos/antagonistas & inibidores , Fator Tu de Elongação de Peptídeos/genética , Fator Tu de Elongação de Peptídeos/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores de Antígenos de Linfócitos B , Proteínas Ribossômicas/antagonistas & inibidores , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas
15.
Talanta ; 153: 152-7, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27130102

RESUMO

This paper describes a reliable analytical method based on ultra-performance liquid chromatography coupled to tandem mass spectrometry to determine F2-isoprostanes and other total byproducts (isoprostanes, isofurans, neuroprostanes and neurofurans) as lipid peroxidation biomarkers in newborn plasma samples. The proposed procedure is characterized by a simple sample treatment employing a reduced sample volume (100µL). Also, it shows a high throughput and high selectivity to determine simultaneously different isoprostane isomers in a large number of samples. The reliability of the described method was demonstrated by analysis of spiked plasma samples, obtaining recoveries between 70% and 130% for most of the analytes. Taking into account the implementation of further clinical studies, it was demonstrated the proper sensitivity of the method by means of the analysis of few human newborn plasma samples. In addition to this, newborn piglet plasma samples (n=80) were analyzed observing that the developed method was suitable to determine the analyte levels present in this kind of samples. Therefore, this analytical method could be applied in further clinical research about establishment of reliable lipid peroxidation biomarkers employing this experimental model.


Assuntos
Peroxidação de Lipídeos , Biomarcadores , Humanos , Recém-Nascido , Isoprostanos , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
16.
Anal Chim Acta ; 886: 214-20, 2015 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-26320656

RESUMO

Byproducts of arachidonic (AA) and docosahexaenoic acid (DHA) oxidation are highly relevant for the study of free radical associated conditions in the perinatal period. Plasma metabolites can provide the clinician with a snapshot of the oxidant status of patients before and after specific clinical interventions (e.g.: supplementation with oxygen). We describe a new andreliable ultra-performance liquid mass spectrometry method to determine F2-isoprostanes and other byproducts (isoprostanes, isofurans, neuroprostanes, neurofurans) in newborn serum samples. Cord blood samples were obtained from severely depressed newborn infants (Apgar score 1 min < 3; arterial cord pH < 7.00), and aliquoted for serum determination and stored at -80 °C. A UHPLC-MS/MS method was employed. It has a series of technical advantages: simple sample treatment; reduced sample volume (100 µL) which is essential for preterm neonates with low circulating blood volume, high throughput of sample analysis (96 samples in less than 24 h) and high selectivity for different isoprostanes isomers. Excellent sensitivity was achieved within limits of detection between 0.06 and 4.2 nmol L(-1), which renders this method suitable to monitoranalyte concentration in newborn samples. The method's precision was satisfactory; with coefficients of variation around 5-12% (intra-day) and 7-17% (inter-day). The reliability of the described method was assessed by analysis of spiked serum samples obtaining recoveries between 70% and 120%. The proposed method has rendered suitable for serum determination for newborn babies at risk of oxygen free radical associated conditions.


Assuntos
Biomarcadores/sangue , Cromatografia Líquida de Alta Pressão/métodos , Peroxidação de Lipídeos , Lipídeos/sangue , Estresse Oxidativo , Espectrometria de Massas em Tandem/métodos , Humanos , Recém-Nascido/sangue , Limite de Detecção
17.
Trends Cell Biol ; 24(2): 118-27, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24018218

RESUMO

Cells are capable of metabolizing a variety of carbon substrates, including glucose, fatty acids, ketone bodies, and amino acids. Cellular fuel choice not only fulfills specific biosynthetic needs, but also enables programmatic adaptations to stress conditions beyond compensating for changes in nutrient availability. Emerging evidence indicates that specific switches from utilization of one substrate to another can have protective or permissive roles in disease pathogenesis. Understanding the molecular determinants of cellular fuel preference may provide insights into the homeostatic control of stress responses, and unveil therapeutic targets. Here, we highlight overarching themes encompassing cellular fuel choice; its link to cell fate and function; its advantages in stress protection; and its contribution to metabolic dependencies and maladaptations in pathological conditions.


Assuntos
Células/metabolismo , Metabolismo Energético , Diferenciação Celular , Células/patologia , Humanos
18.
Cancer Cell ; 22(4): 547-60, 2012 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-23079663

RESUMO

Molecular signatures have identified several subsets of diffuse large B cell lymphoma (DLBCL) and rational targets within the B cell receptor (BCR) signaling axis. The OxPhos-DLBCL subset, which harbors the signature of genes involved in mitochondrial metabolism, is insensitive to inhibition of BCR survival signaling but is functionally undefined. We show that, compared with BCR-DLBCLs, OxPhos-DLBCLs display enhanced mitochondrial energy transduction, greater incorporation of nutrient-derived carbons into the tricarboxylic acid cycle, and increased glutathione levels. Moreover, perturbation of the fatty acid oxidation program and glutathione synthesis proved selectively toxic to this tumor subset. Our analysis provides evidence for distinct metabolic fingerprints and associated survival mechanisms in DLBCL and may have therapeutic implications.


Assuntos
Linfoma Difuso de Grandes Células B/metabolismo , Sobrevivência Celular , Ciclo do Ácido Cítrico , Ácidos Graxos/metabolismo , Humanos , Linfoma Difuso de Grandes Células B/patologia , Linfoma Difuso de Grandes Células B/terapia , Mitocôndrias/metabolismo , Oxirredução , Fosforilação Oxidativa , Proteoma , Receptores de Antígenos de Linfócitos B/fisiologia
20.
Acta Cytol ; 46(4): 749-52, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12146046

RESUMO

BACKGROUND: Apocrine metaplastic cells are frequently encountered in fine needle aspirates of breast lesions. Atypical apocrine metaplastic cells with signet ring features can also occur, and their presence may present a diagnostic dilemma in the differentiation of benign versus malignant lesions. CASE: A fine needle aspirate of a 2.5 x 1.0-cm, subareolar mass in a 47-year-old female showed atypical cells with signet ring morphology. Also present were clusters of cells that were enlarged and showed nuclear atypia, prominent nucleoli and cytoplasmic granules. Papillary cohesive clusters of ductal cells were also identified. The fine needle aspiration diagnosis was mucinous carcinoma. The nodule was excised, and the histologic diagnosis was sclerosing ductal papilloma with atypical apocrine metaplasia. CONCLUSION: Atypical apocrine cells can be misinterpreted as mucinous carcinoma or usual duct adenocarcinoma on fine needle aspiration cytology. We present clues that may help in rendering the correct interpretation.


Assuntos
Adenocarcinoma Mucinoso/patologia , Glândulas Apócrinas/patologia , Neoplasias da Mama/patologia , Metaplasia/patologia , Biópsia por Agulha , Nucléolo Celular/ultraestrutura , Núcleo Celular/ultraestrutura , Citoplasma/ultraestrutura , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Papiloma/patologia
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