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1.
Artigo em Inglês | MEDLINE | ID: mdl-38568152

RESUMO

We investigated if a bout of exercise in a hot environment (HEAT) would reduce the postprandial hyperglycemia induced by glucose ingestion. The hypothesis was that HEAT stimulating glycogen use would increase the disposal of the ingested glucose (i.e., OGTT; 75 g of glucose). Separated by at least 1 week, nine young-healthy individuals underwent three trials after an overnight fast in a randomized order. Two trials included 50 min of pedaling at 58±5% VO2MAX either in a thermoneutral (21±1ºC; NEUTRAL) or in a hot environment (33±1ºC; HEAT) eliciting similar energy expenditure (503±101 kcals). These two trials were compared to a no-exercise trial (NO EXER). Twenty min after exercise (or rest), subjects underwent an OGTT, while carbohydrate oxidation (CHOxid, using indirect calorimetry) plasma blood glucose, insulin concentrations (i.e., [glucose], [insulin]), and double tracer glucose kinetics ([U- 13C] glucose ingestion and [6,6-2H2] glucose infusion) were monitored for 120 min. At rest, [glucose], [insulin], and rates of appearance/disappearance of glucose in plasma (glucose Ra/Rd) were similar among trials. During exercise, heart rate, tympanic temperature, [glucose], glycogen oxidation, and total CHOxid were higher during HEAT than NEUTRAL (i.e., 149±35 vs 124±31 µmol·kg-1·min-1, p=0.010). However, during the following OGTT glucose Rd was similar in HEAT and NEUTRAL (i.e., 25.1±3.6 vs 25.2±5.3 µmol·kg-1·min-1, p=0.981). Insulin sensitivity (i.e., ISIMATSUDA) only improved in NEUTRAL compared to NO EXER (10.1±4.6 vs 8.8±3.7 a.u.; p=0.044). In summary, stimulating carbohydrate use with exercise in a hot environment does not improve postprandial plasma glucose disposal or insulin sensitivity in a subsequent OGTT.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38583741

RESUMO

The white shrimp Penaeus (Litopenaeus) vannamei is the most cultivated shrimp worldwide. Compared to other shrimp species, it has higher resistance to adverse conditions. During hypoxia, the shrimp reduces oxygen consumption and adjusts energy metabolism via anaerobic glycolysis, among other strategies. Hexokinase (HK) is the first enzyme of glycolysis and a key regulation point. In mammals and other vertebrates, there are several tissue-specific HK isoforms with differences in expression and enzyme activity. In contrast, crustacean HKs have been relatively little studied. We studied the P. vannamei HK isoforms during hypoxia and reoxygenation. We cloned two HK1 sequences named HK1-long (1455 bp) and HK1-short (1302 bp), and one HK2 (1344 bp). In normoxia, total HK1 expression is higher in hepatopancreas, while HK2 is higher in gills. Severe hypoxia (1 mg/L of DO) after 12 h exposure and 1 h of reoxygenation increased HK1 expression in both organs, but HK2 expression changed differentially. In hepatopancreas, HK2 expression increased in 6 and 12 h of hypoxia but diminished to normoxia levels after reoxygenation. In gills, HK2 expression decreased after 12 h of hypoxia. HK activity increased in hepatopancreas after 12 h hypoxia, opposite to gills. These results indicate that shrimp HK isoforms respond to hypoxia and reoxygenation in a tissue-specific manner. Intracellular glucose levels did not change in any case, showing the shrimp ability to maintain glucose homeostasis during hypoxia.


Assuntos
Penaeidae , Animais , Penaeidae/metabolismo , Hexoquinase/genética , Hexoquinase/metabolismo , Sequência de Aminoácidos , Hipóxia/metabolismo , Oxigênio/metabolismo , Isoformas de Proteínas/metabolismo , Glucose/metabolismo , Hepatopâncreas/metabolismo , Mamíferos/metabolismo
3.
Front Cell Neurosci ; 18: 1347535, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650656

RESUMO

Astrocytes represent the most abundant cell type in the brain, where they play critical roles in synaptic transmission, cognition, and behavior. Recent discoveries show astrocytes are involved in synaptic dysfunction during Alzheimer's disease (AD). AD patients have imbalanced cholesterol metabolism, demonstrated by high levels of side-chain oxidized cholesterol known as 27-hydroxycholesterol (27-OH). Evidence from our laboratory has shown that elevated 27-OH can abolish synaptic connectivity during neuromaturation, but its effect on astrocyte function is currently unclear. Our results suggest that elevated 27-OH decreases the astrocyte function in vivo in Cyp27Tg, a mouse model of brain oxysterol imbalance. Here, we report a downregulation of glutamate transporters in the hippocampus of CYP27Tg mice together with increased GFAP. GLT-1 downregulation was also observed when WT mice were fed with high-cholesterol diets. To study the relationship between astrocytes and neurons, we have developed a 3D co-culture system that allows all the cell types from mice embryos to differentiate in vitro. We report that our 3D co-cultures reproduce the effects of 27-OH observed in 2D neurons and in vivo. Moreover, we found novel degenerative effects in astrocytes that do not appear in 2D cultures, together with the downregulation of glutamate transporters GLT-1 and GLAST. We propose that this transporter dysregulation leads to neuronal hyperexcitability and synaptic dysfunction based on the effects of 27-OH on astrocytes. Taken together, these results report a new mechanism linking oxysterol imbalance in the brain and synaptic dysfunction through effects on astrocyte function.

4.
Can J Public Health ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647638

RESUMO

OBJECTIVE: Statistically model the likelihood of changes in the activities of daily living (ADLs) over time for three groups of older adults: those on a pension at all time periods, those never on a pension, and those who transition onto a public pension. METHODS: Our study used data from the Canadian Longitudinal Study on Aging (CLSA), a large national survey. We used data from baseline (2010-2015) and the first follow-up wave (2015-2018). We used logistic regression to model the likelihood of ADL changes in males and females by pension receipt status, controlling for several potential confounders and allowing for the impact of public pensions to be modified by baseline income. RESULTS: The magnitudes of the estimates indicated that those who transition to a public pension are less likely to report ADL degradation and more likely to report ADL improvement compared to those with no public pension. In the lowest baseline income group, those who transitioned onto a pension at follow-up had a 15% (male) or 11% (female) lower likelihood of reporting degraded ADL scores compared to those not receiving a pension at follow-up. Those who transitioned onto a pension in the lowest income group were more likely to report an improved ADL score at follow-up. CONCLUSION: Our results could provide evidence for the potential health benefits of more comprehensive guaranteed annual income programs beyond the pension program. The penalty of being low-income was mitigated by the stability of the pension income in terms of ADL improvement or degradation.


RéSUMé: OBJECTIF: Modeler statistiquement la probabilité de changements des activités de la vie quotidienne (AVQ) à travers le temps pour trois groupes d'adultes âgés : ceux qui reçoivent une pension tout le temps, ceux qui ne reçoivent jamais une pension, et ceux qui transitionnent à recevoir une pension pendant la période d'étude. MéTHODES: Notre étude a utilisé les données de l'Étude longitudinale canadienne sur le vieillissement (ÉLCV), une grande enquête nationale. On a utilisé les données de base (2010-2015) et de la première vague (2015-2018). On a utilisé une régression logistique pour modeler la probabilité de changement des AVQ dans les hommes et les femmes par statut de réception de pension, en ajustant plusieurs facteurs de confusion potentielles et pour que l'impact de pensions publiques soient modifiées par le revenu de base. RéSULTATS: La magnitude des estimations a indiqué que ceux qui font une transition à une pension publique sont moins probables de signaler une dégradation des AVQ et plus probables de déclarer une amélioration comparés à ceux qui ne reçoivent pas une pension publique. Parmi le groupe de revenu de base le plus bas, ceux qui ont transitionné à recevoir une pension au suivi avaient 15 % (hommes) ou 11 % (femmes) moins de chance de déclarer une évaluation de AVQ dégradée comparé à ceux qui ne recevaient pas une pension au suivi. Ceux qui ont transitionné à recevoir une pension dans le groupe de revenu de base le plus bas étaient plus probables de déclarer une évaluation de AVQ améliorée au suivi. CONCLUSION: Nos résultats pourraient apporter la preuve pour les avantages potentiels des programmes compréhensifs de revenu garanti qui vont plus loin que les pensions publiques. La pénalité de faire partie du groupe de revenu le plus bas est atténuée par la stabilité des revenus de pension en ce qui concerne l'amélioration ou la dégradation des AVQ.

5.
CJC Open ; 6(2Part B): 436-441, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38487047

RESUMO

Cardiac rehabilitation is associated with lower mortality and improved psychosocial outcomes. However, disparities exist in referral and access to cardiac rehabilitation for Nova Scotian women, a situation exacerbated by the COVID-19 pandemic. Women@Heart (W@H) is a 4-month community-based peer support program developed and validated by the University of Ottawa Heart Institute, for women living with heart disease. The program aims to empower women with coping strategies, provide a supportive learning environment, and establish volunteer advocacy groups. The primary objective of this study is to evaluate the implementation feasibility of the W@H program for women living in Nova Scotia. The primary outcome is the implementation feasibility of W@H in Nova Scotia, measured through participant attendance and program completion rates. Peer leaders will record participant attendance. The psychosocial impact of W@H will be assessed using psychometric tools that measure the following: social support, adaptive coping, stress, symptoms of anxiety and depression, and health-related and disease-specific quality of life. Data will be collected using a pre- and post-program questionnaire administered to participants. The pilot program is expected to commence in the first quarter of 2024. One peer leader with lived experience of heart disease, who has previously completed the W@H program as a participant, has been trained. Participants have been identified through healthcare provider referral, self-referral, brochures, and peer-networking. Each cohort will consist of 5-10 participants. The W@H pilot project will assess the implementation feasibility and the impact of community-based peer support on the well-being of Nova Scotian women living with heart disease.


La réadaptation cardiaque est associée à une mortalité plus faible et à des bienfaits psychosociaux. Cependant, il existe des disparités en ce qui a trait à l'orientation et à l'accès à la réadaptation cardiaque pour les femmes de la Nouvelle-Écosse, une situation exacerbée par la pandémie de COVID-19. Femmes@Cœur est un programme de soutien collectif par les pairs, créé et validé par l'Institut de cardiologie de l'Université d'Ottawa, à l'intention des femmes atteintes d'une maladies du cœur. Le programme vise à autonomiser les femmes en leur proposant des stratégies d'adaptation, à leur fournir un environnement propice à l'apprentissage et à former des groupes de bénévoles pour la défense de leurs intérêts. La présente étude a pour principal objectif d'évaluer la faisabilité de la mise en œuvre du programme Femmes@Cœur pour les femmes de la Nouvelle-Écosse. Le critère d'évaluation principal de l'étude est la faisabilité de la mise en œuvre du programme Femmes@Cœur en Nouvelle-Écosse, déterminée par la mesure des taux de participation et d'achèvement du programme. Des responsables parmi les pairs consigneront la présence des participantes. Les répercussions psychosociales du programme Femmes@Cœur seront évaluées à l'aide d'outils psychométriques mesurant une gamme de paramètres : soutien social, stratégies d'adaptation, niveau de stress, symptômes d'anxiété et de dépression, et qualité de vie liée à la santé et à la maladie en question. Les données seront recueillies au moyen de questionnaires administrés aux participantes avant et après le programme, et le projet pilote devrait être lancé le premier trimestre de 2024. Une responsable parmi les pairs, elle-même atteinte d'une maladie du cœur et ayant déjà pris part au programme Femmes@Cœur en tant que participante, a été formée à cet effet. Les participantes ont été trouvées de diverses façons : orientation par un professionnel de la santé, inscription spontanée, brochures et réseautage entre pairs. Chaque cohorte sera par ailleurs composée de 5 à 10 participantes. Enfin, le projet pilote Femmes@Cœur évaluera la faisabilité de la mise en œuvre et les répercussions du soutien collectif entre pairs sur le bien-être des femmes de la Nouvelle-Écosse atteintes de maladies cardiaques.

6.
J Clin Med ; 13(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38541764

RESUMO

Background: Respiratory tract infections remain among the leading causes of mortality worldwide. The COVID-19 pandemic has highlighted the importance of mucosal immunity in defending against infectious agents. Vitamin A is known to influence the production of secretory immunoglobulin A (SIgA) predominantly in the gut, where it is a critical component of the first line of defense on mucosal surfaces. Methods: This cross-sectional study, conducted 14 days post-positive COVID-19 diagnosis, aimed to determine the relationship between the nutritional status of vitamin A and SIgA levels in COVID-19 outpatients. Serum and saliva samples were collected. Vitamin A nutritional status was determined based on the assessment of dietary intake and the analysis of retinol-binding protein 4 (RBP4). SIgA levels were analyzed from salivary samples. In addition, serum antibodies were analyzed. Results: Dietary vitamin A intake and RBP4 levels positively correlated with SIgA. Patients with higher vitamin A intake showed higher SIgA/IgG1 and SIgA/IgG3 ratios, while those with higher RBP4 levels showed higher SIgA/IgM, SIgA/IgG1, and SIgA/IgG2 ratios. Conclusions: These findings underscore a significant correlation between vitamin A nutritional status and SIgA levels in COVID-19 outpatients, which may suggest the potential importance of maintaining optimal vitamin A levels for the prevention of viral infections.

7.
Microbiol Spectr ; 12(4): e0380523, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38426766

RESUMO

Pasteurella multocida is an upper respiratory tract commensal in several mammal and bird species but can also cause severe disease in humans and in production animals such as poultry, cattle, and pigs. In this study, we performed whole-genome sequencing of P. multocida isolates recovered from a range of human infections, from the mouths of cats, and from wounds on dogs. Together with publicly available P. multocida genome sequences, we performed phylogenetic and comparative genomic analyses. While isolates from cats and dogs were spread across the phylogenetic tree, human infections were caused almost exclusively by subsp. septica strains. Most of the human isolates were capsule type A and LPS type L1 and L3; however, some strains lacked a capsule biosynthesis locus, and some strains contained a novel LPS outer-core locus, distinct from the eight LPS loci that can currently be identified using an LPS multiplex PCR. In addition, the P. multocida strains isolated from human infections contained novel mobile genetic elements. We compiled a curated database of known P. multocida virulence factor and antibiotic resistance genes (PastyVRDB) allowing for detailed characterization of isolates. The majority of human P. multocida isolates encoded a reduced range of iron receptors and contained only one filamentous hemagglutinin gene. Finally, gene-trait analysis identified a putative L-fucose uptake and utilization pathway that was over-represented in subsp. septica strains and may represent a novel host predilection mechanism in this subspecies. Together, these analyses have identified pathogenic mechanisms likely important for P. multocida zoonotic infections.IMPORTANCEPasteurella multocida can cause serious infections in humans, including skin and wound infections, pneumonia, peritonitis, meningitis, and bacteraemia. Cats and dogs are known vectors of human pasteurellosis, transmitting P. multocida via bite wounds or contact with animal saliva. The mechanisms that underpin P. multocida human predilection and pathogenesis are poorly understood. With increasing identification of antibiotic-resistant P. multocida strains, understanding these mechanisms is vital for developing novel treatments and control strategies to combat P. multocida human infection. Here, we show that a narrow range of P. multocida strains cause disease in humans, while cats and dogs, common vectors for zoonotic infections, can harbor a wide range of P. multocida strains. We also present a curated P. multocida-specific database, allowing quick and detailed characterization of newly sequenced P. multocida isolates.


Assuntos
Infecções por Pasteurella , Pasteurella multocida , Humanos , Gatos , Bovinos , Animais , Suínos , Cães , Pasteurella multocida/genética , Filogenia , Lipopolissacarídeos/metabolismo , Infecções por Pasteurella/veterinária , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Zoonoses , Mamíferos
8.
Psychiatry Res ; 335: 115871, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38547600

RESUMO

Abnormalities in immune function have been described in schizophrenia but few studies have investigated cytokines in cerebrospinal fluid (CSF) and their correlation with blood levels. In this cross-sectional study, cytokines were measured in CSF and plasma of 30 subjects with schizophrenia spectrum disorder (SSD) diagnosis and 23 healthy volunteers (HV). Results showed that CSF TNFα was increased in SSD subjects compared to HV and there were no correlations between CSF and plasma cytokine levels. The present findings provide evidence of dysregulation of TNFα in CSF of schizophrenia. These results identify elevated CSF TNFα levels as a potential biomarker in schizophrenia.


Assuntos
Esquizofrenia , Humanos , Citocinas , Fator de Necrose Tumoral alfa , Estudos Transversais , Biomarcadores/líquido cefalorraquidiano
9.
Int J Mol Sci ; 25(5)2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38474248

RESUMO

SARS-CoV-2 induces a hyperinflammatory reaction due to the excessive release of cytokines during the immune response. The bacterial endotoxin lipopolysaccharide (LPS) contributes to the low-grade inflammation associated with the metabolic syndrome, enhancing the hyperinflammatory reaction induced by the SARS-CoV-2 infection. The intake of sodium nitrate, a precursor of nitrite and nitric oxide, influences the antioxidant and pro-inflammatory gene expression profile after immune stimulation with LPS in peripheral blood mononuclear cells from metabolic syndrome patients. We aimed to assess the inflammatory and antioxidant responses of immune cells from metabolic syndrome patients to exposure to the SARS-CoV-2 spike protein (S protein) together with LPS and the effect of nitrite in these responses. Whole blood samples obtained from six metabolic syndrome patients were cultured for 16 h at 37 °C with four different media: control medium, control medium plus LPS (100 ng/mL), control medium plus LPS (100 ng/mL) plus S protein (10 ng/mL), and control medium plus LPS (100 ng/mL) plus S protein (10 ng/mL) plus nitrite (5 µM). Immune stimulation with the LPS/S protein enhanced nitrate biosynthesis from nitrite oxidation and probably from additional organic precursors. In vitro incubations with the LPS/S protein enhanced the expression and/or release of pro-inflammatory TNFα, IL-6, IL-1ß, and TLR4, as well as the expression of the anti-inflammatory IL-1ra and IL-10 and antioxidant enzymes. Nitrite attenuated the pro- and anti-inflammatory response induced by the S protein without interfering with the activation of TLR4 and antioxidant enzyme expression, raising the possibility that nitrite could have potential as a coadjutant in the treatment of COVID-19.


Assuntos
COVID-19 , Síndrome Metabólica , Glicoproteína da Espícula de Coronavírus , Humanos , Lipopolissacarídeos/farmacologia , Nitritos , Antioxidantes/metabolismo , Leucócitos Mononucleares/metabolismo , Ativação Enzimática , Receptor 4 Toll-Like/metabolismo , SARS-CoV-2/metabolismo , Citocinas/metabolismo , Anti-Inflamatórios
10.
Scand J Med Sci Sports ; 34(2): e14574, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38389141

RESUMO

AIM: To determine whether glucose volume of distribution (VdGLUCOSE ) affects the diagnosis of impaired insulin sensitivity (IS) when using an intravenous glucose tolerance test (IVGTT). METHODS: Individuals with distinct levels of IS underwent IVGTT after an overnight fast. The prediabetic group (Prediab; n = 33) differed from the healthy group (Healthy; n = 14) in their larger glycosylated hemoglobin (HbA1c of 5.9 ± 0.3 vs. 5.4 ± 0.1%; 41 ± 4 vs. 36 ± 1 mmol/mol; p < 0.001), percent body fat (37 ± 6 vs. 24 ± 3%; p < 0.001) and cardiovascular fitness level (VO2MAX 22 ± 5 vs. 44 ± 5 mL of O2 ·kg-1 ·min-1 ; p < 0.001). Ten minutes after intravenous infusion of the glucose bolus (i.e., 35 g in a 30% solution), VdGLUCOSE was assessed from the increases in plasma glucose concentration. IS was calculated during the next 50 min using the slope of glucose disappearance and the insulin time-response curve. RESULTS: VdGLUCOSE was higher in Healthy than in Prediab (230 ± 49 vs. 185 ± 21 mL·kg-1 ; p < 0.001). VdGLUCOSE was a strong predictor of IS (ß standardized coefficient 0.362; p = 0.004). VO2MAX was associated with VdGLUCOSE and IS (Pearson r = 0.582 and 0.704, respectively; p < 0.001). However, body fat was inversely associated with VdGLUCOSE and IS (r = -0.548 and -0.555, respectively; p < 0.001). CONCLUSIONS: Since fat mass is inversely related to VdGLUCOSE and in turn, VdGLUCOSE affects the calculations of IS, the IV glucose bolus dose should be calculated based on fat-free mass rather than body weight for a more accurate diagnosis of impaired IS.


Assuntos
Resistência à Insulina , Humanos , Teste de Tolerância a Glucose , Glucose , Insulina , Glicemia
11.
BMC Complement Med Ther ; 24(1): 90, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360684

RESUMO

BACKGROUND: Diabetic peripheral neuropathy (DPN) is the most common complication of type 2 diabetes mellitus (T2DM); its diagnosis and treatment are based on symptomatic improvement. However, as pharmacological therapy causes multiple adverse effects, the implementation of acupunctural techniques, such as electroacupuncture (EA) has been suggested as an alternative treatment. Nonetheless, there is a lack of scientific evidence, and its mechanisms are still unclear. We present the design and methodology of a new clinical randomized trial, that investigates the effectiveness of EA for the treatment of DPN. METHODS: This study is a four-armed, randomized, controlled, multicenter clinical trial (20-week intervention period, plus 12 weeks of follow-up after concluding intervention). A total of 48 T2DM patients with clinical signs and symptoms of DPN; and electrophysiological signs in the Nerve Conduction Study (NCS); will be treated by acupuncture specialists in outpatient units in Mexico City. Patients will be randomized in a 1:1 ratio to one of the following four groups: (a) short fibre DPN with EA, (b) short fibre DPN with sham EA, (c) axonal DPN with EA and (d) axonal DPN with sham EA treatment. The intervention will consist of 32 sessions, 20 min each, per patient over two cycles of intervention of 8 weeks each and a mid-term rest period of 4 weeks. The primary outcome will be NCS parameters, and secondary outcomes will include DPN-related symptoms and pain by Michigan Neuropathy Screening Instrument (MNSI), Michigan Diabetic Neuropathy Score (MDNS), Dolour Neuropatique Score (DN-4), Semmes-Westein monofilament, Numerical Rating Scale (NRS) for pain assessment, and the 36-item Short Form Health Survey (SF-36). To measure quality of life and improve oxidative stress, the inflammatory response; and genetic expression; will be analysed at the beginning and at the end of treatment. DISCUSSION: This study will be conducted to compare the efficacy of EA versus sham EA combined with conventional diabetic and neuropathic treatments if needed. EA may improve NCS, neuropathic pain and symptoms, oxidative stress, inflammatory response, and genetic expression, and it could be considered a potential coadjutant treatment for the management of DPN with a possible remyelinating effect. TRIAL REGISTRATION: ClinicalTrials.gov. NCT05521737 Registered on 30 August 2022. International Clinical Trials Registry Platform (ICTRP) ISRCTN97391213 Registered on 26 September 2022 [2b].


Assuntos
Terapia por Acupuntura , Diabetes Mellitus Tipo 2 , Neuropatias Diabéticas , Eletroacupuntura , Humanos , Neuropatias Diabéticas/terapia , Eletroacupuntura/métodos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/terapia , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
12.
bioRxiv ; 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38370628

RESUMO

DNA-PAINT combined with total Internal Reflection Fluorescence (TIRF) microscopy enables the highest localization precisions, down to single nanometers in thin biological samples, due to TIRF's unique method for optical sectioning and attaining high contrast. However, most cellular targets elude the accessible TIRF range close to the cover glass and thus require alternative imaging conditions, affecting resolution and image quality. Here, we address this limitation by applying ultrathin physical cryosectioning in combination with DNA-PAINT. With "tomographic & kinetically-enhanced" DNA-PAINT (tokPAINT), we demonstrate the imaging of nuclear proteins with sub-3 nanometer localization precision, advancing the quantitative study of nuclear organization within fixed cells and mouse tissues at the level of single antibodies. We believe that ultrathin sectioning combined with the versatility and multiplexing capabilities of DNA-PAINT will be a powerful addition to the toolbox of quantitative DNA-based super-resolution microscopy in intracellular structural analyses of proteins, RNA and DNA in situ.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38224831

RESUMO

Salinity and temperature influence growth, survival, and reproduction of crustacean species such as Penaeus vannamei where Na +/K+-ATPase plays a key role in maintaining osmotic homeostasis in different salinity conditions. This ability is suggested to be mediated by other proteins including neuropeptides such as the crustacean hyperglycemic hormones (CHHs), and heat shock proteins (HSPs). The mRNA expression of Na+/K+-ATPase, HSP60, HSP70, CHH-A, and CHH-B1, was analyzed by qPCR in shrimp acclimated to different salinities (10, 26, and 40 PSU) and temperature conditions (20, 23, 26, 29, and 32 °C) to evaluate their uses as molecular stress biomarkers. The results showed that the hemolymph osmoregulatory capacity in shrimp changed with exposure to the different salinities. From 26 to 32 °C the Na+/K+-ATPase expression increased significantly at 10 PSU relative to shrimp acclimated at 26 PSU and at 20 °C increased at similar values independently of salinity. The highest HSP expression levels were obtained by HSP70 at 20 °C, suggesting a role in protecting proteins such as Na+/K+ -ATPase under low-temperature and salinity conditions. CHH-A was not expressed in the gill under any condition, but CHH-B1 showed the highest expression at the lowest temperatures and salinities, suggesting its participation in the Na+/K+-ATPase induction. Since Na+/K+-ATPase, HSPs, and CHHs seem to participate in maintaining the osmo-ionic balance and homeostasis in P. vannamei, their expression levels may be used as a stress biomarkers to monitor marine crustacean health status when acclimated in low salinity and temperature conditions.


Assuntos
Penaeidae , Animais , Penaeidae/metabolismo , Salinidade , Adenosina Trifosfatases/metabolismo , Temperatura , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , ATPase Trocadora de Sódio-Potássio/genética , ATPase Trocadora de Sódio-Potássio/metabolismo , Brânquias/metabolismo
14.
Adv Lab Med ; 4(3): 279-287, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38075165

RESUMO

Objectives: Hereditary breast and ovarian cancer (HBOC) follows an autosomal dominant inheritance pattern of cancer susceptibility genes. The risk of developing this disease is primarily associated with germline mutations in the BRCA1 and BRCA2 genes. The advent of massive genetic sequencing technologies has expanded the mutational spectrum of this hereditary syndrome, thereby increasing the number of variants of uncertain clinical significance (VUS) detected by genetic testing. Methods: A prevalence study of HBOC was performed within 2,928 families from the Region of Murcia, in southeastern Spain. Genetic testing enabled the identification of recurrent pathogenic variants and founder mutations, which were mainly related to the BRCA1 and BRCA2 genes. VUS testing was performed using a prioritization algorithm designed by our working group. Results: Variants c.68_69del, c.212+1G>A, and c.5123C>A were detected in 30 % of BRCA1 carriers, whereas exon 2 deletion concurrent with c.3264dupT, c.3455T>G and c.9117G>A variants were found in 30 % of BRCA2 carriers. A total of 16 VUS (15 %) were prioritized. Conclusions: The genotype-phenotype correlation observed in our study is consistent with the scientific literature. Furthermore, the founder effect of c.1918C>T (BRCA1) and c.8251_8254del (ATM) was verified in the Murcian population, whereas exon 2 deletion (BRCA2) was proven to be a Spanish founder mutation. Our algorithm enabled us to prioritize potentially pathogenic VUS that required further testing to determine their clinical significance and potential role in HBOC.

16.
J Physiol ; 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38015017

RESUMO

A supervised intense aerobic exercise program improves the health of individuals with metabolic syndrome (MetS). However, it is unclear whether the timing of training within the 24 h day would influence those health benefits. The present study aimed to determine the influence of morning vs. afternoon exercise on body composition, cardiometabolic health and components of MetS. One hundred thirty-nine individuals with MetS were block randomized into morning (AMEX; n = 42) or afternoon (PMEX; n = 59) exercise training groups, or a non-training control group (Control; n = 38). Exercise training was comprised of 48 supervised high-intensity interval sessions distributed over 16 weeks. Body composition, cardiorespiratory fitness (assessed by V ̇ O 2 max ${\dot V_{{{\mathrm{O}}_{\mathrm{2}}}{\mathrm{max}}}}$ ), maximal fat oxidation (FOmax ), blood pressure and blood metabolites were assessed before and after the intervention. Compared with the non-training Control, both exercise groups improved similarly body composition (-0.7% fat loss; P = 0.002), waist circumference (-2.1 cm; P < 0.001), diastolic blood pressure (-3.8 mmHg; P = 0.004) and V ̇ O 2 max ${\dot V_{{{\mathrm{O}}_{\mathrm{2}}}{\mathrm{max}}}}$ (3.5 mL kg-1   min-1 ; P < 0.001) with no differences between training groups. AMEX, in comparison with PMEX, reduced systolic blood pressure (-4% vs. -1%; P = 0.019), plasma fasting insulin concentration (-12% vs. -5%; P = 0.001) and insulin resistance (-14% vs. -4%; P = 0.006). Furthermore, MetS Z score was further reduced in the AMEX compared to PMEX (-52% vs. -19%; P = 0.021) after training. In summary, high-intensity aerobic exercise training in the morning in comparison to training in the afternoon is somewhat more efficient at reducing cardiometabolic risk factors (i.e. systolic blood pressure and insulin sensitivity). KEY POINTS: The effect of exercise time of day on health promotion is an area that has gained interest in recent years; however, large-scale, randomized-control studies are scarce. People with metabolic syndrome (MetS) are at risk of developing cardiometabolic diseases and reductions in this risk with exercise training can be precisely gauged using a compound score sensitive to subtle evolution in each MetS component (i.e. Z score). Supervised aerobic exercise for 16 weeks (morning and afternoon), without dietary restriction, improved cardiorespiratory and metabolic fitness, body composition and mean arterial pressure compared to a non-exercise control group. However, training in the morning, without changes in exercise dose or intensity, reduced systolic blood pressure and insulin resistance further compared to when training in the afternoon. Thus, high-intensity aerobic exercise training in the morning is somewhat more efficient in improving the health of individuals with metabolic syndrome.

17.
Appetite ; 190: 107030, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37678585

RESUMO

Evidence about the association between breastfeeding and its duration with growth, appetite and satiety indicators, and adiposity in low and middle-income countries facing nutritional transition is scarce. The aim of this study was to evaluate the association between longitudinal patterns of breastfeeding (exclusive [EBF] and continued [CBF]) with adiposity and growth, and the mediating role of appetite and satiety indicators in these associations in Mexican children during the first 2 years of life. Information from 378 mother-child pairs from the MAS-Lactancia birth cohort was analysed. Information was collected at birth and at months 1, 3, 6, 9, 12, 18 and 24 of life. Duration of EBF and CBF was computed. Linear mixed models were used to assess the association of EBF and CBF with growth and adiposity. Path analysis was used for mediation analysis. Compared with the reference group (EBF duration <1 month), males with >3 to ≤6 months of EBF had less abdominal circumference (ß = -0.66, p = 0.05), Z-score weight-for-length (ß = -0.17, p = 0.19) and length-for-age (ß = -0.49, p < 0.01). Participants without CBF beyond 6 months had higher BMI Z-score (ß = 0.19, p < 0.01), abdominal circumference (ß = 0.62, p < 0.01) and skinfold sum (ß = 0.80, p = 0.09), and o difference in length-for-age. For EBF, mediation was confirmed for satiety responsiveness on the association with BMI Z-Score, for food fussiness for the association with abdominal circumference and length-for-age Z-score, and enjoyment of food on the association with length-for-age Z-score. For CBF, mediation was confirmed for food fussiness in the association with length-for-age. This study suggests that a longer exposure to EBF and CBF is associated with lower adiposity in children under 2 years of age, and that this association could be partially mediated by appetite and satiety indicators.

18.
Mar Environ Res ; 192: 106184, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37769555

RESUMO

Persistent organic pollutants (POPs) are ubiquitous in marine ecosystems. These compounds can be accumulated in water, sediments and organisms, persist in time, and have toxic effects in human and wildlife. POPs can be uptaken and bioaccumulated by crustaceans, affecting different physiological processes, including energy metabolism, immunity, osmoregulation, excretion, growth, and reproduction. Nonetheless, animals have evolved sub-cellular mechanisms for detoxification and protection from chemical stress. POPs induce the activity of enzymes involved in xenobiotic metabolism and antioxidant systems, that in vertebrates are importantly regulated at gene expression (transcriptional) level. However, the activation and control of these enzyme systems upon the exposure to POPs have been scarcely studied in invertebrate species, including crustaceans. Herein, we summarize various aspects of the bioaccumulation of POPs in marine crustaceans and their physiological effects. We specially focus on the regulation of xenobiotics metabolism and antioxidant enzymes as key sub-cellular mechanisms for detoxification and protection from chemical stress.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Animais , Humanos , Poluentes Orgânicos Persistentes , Ecossistema , Bioacumulação , Antioxidantes , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise
19.
Am J Physiol Endocrinol Metab ; 325(4): E310-E324, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37584610

RESUMO

The potential interaction between metformin and exercise on glucose-lowering effects remains controversial. We studied the separated and combined effects of metformin and/or exercise on fasting and postprandial insulin sensitivity in individuals with pre-diabetes and type 2 diabetes (T2D). Eight T2D adults (60 ± 4 yr) with overweight/obesity (32 ± 4 kg·m-2) under chronic metformin treatment (9 ± 6 yr; 1281 ± 524 mg·day-1) underwent four trials; 1) taking their habitual metformin treatment (MET), 2) substituting during 96 h their metformin medication by placebo (PLAC), 3) placebo combined with 50 min bout of high-intensity interval exercise (PLAC + EX), and 4) metformin combined with exercise (MET + EX). Plasma glucose kinetics using stable isotopes (6,6-2H2 and [U-13C] glucose), and glucose oxidation by indirect calorimetry, were assessed at rest, during exercise, and in a subsequent oral glucose tolerance test (OGTT). Postprandial glucose and insulin concentrations were analyzed as mean and incremental area under the curve (iAUC), and insulin sensitivity was calculated (i.e., MATSUDAindex and OGISindex). During OGTT, metformin reduced glucose iAUC (i.e., MET and MET + EX lower than PLAC and PLAC + EX, respectively; P = 0.023). MET + EX increased MATSUDAindex above PLAC (4.8 ± 1.4 vs. 3.3 ± 1.0, respectively; P = 0.018) and OGISindex above PLAC (358 ± 52 vs. 306 ± 46 mL·min-1·m-2, respectively; P = 0.006). Metformin decreased the plasma appearance of the ingested glucose (Ra OGTT; MET vs. PLAC, -3.5; 95% CI -0.1 to -6.8 µmol·kg-1·min-1; P = 0.043). Metformin combined with exercise potentiates insulin sensitivity during an OGTT in individuals with pre-diabetes and type 2 diabetes. Metformin's blood glucose-lowering effect seems mediated by decreased oral glucose entering the circulation (gut-liver effect) an effect partially blunted after exercise.NEW & NOTEWORTHY Metformin is the most prescribed oral antidiabetic medicine in the world but its mechanism of action and its interactions with exercise are not fully understood. Our stable isotope tracer data suggested that metformin reduces the rates of oral glucose entering the circulation (gut-liver effect). Exercise, in turn, tended to reduce postprandial insulin blood levels potentiating metformin improvements in insulin sensitivity. Thus, exercise potentiates metformin improvements in glycemic control and should be advised to metformin users.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Metformina , Estado Pré-Diabético , Adulto , Humanos , Metformina/farmacologia , Metformina/uso terapêutico , Glucose , Estado Pré-Diabético/tratamento farmacológico , Cinética , Glicemia , Insulina
20.
BMC Nurs ; 22(1): 269, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37580681

RESUMO

BACKGROUND: Job satisfaction is a key factor for the successful transition of newly graduated nurses (NGNs) and for retaining NGNs in their workplaces. However, there is limited evidence of the relationship between satisfaction regarding the nursing education program and NGNs' job satisfaction in the first year after graduation. Therefore, this study aims to examine the association of the nursing education related factors and NGNs' job satisfaction. METHODS: A cross-sectional study design with the utilization of data collected from the same respondents one year earlier as educational factors was applied. The data were collected from NGNs (n = 557) in 10 European countries using an electronic survey between February 2019 and September 2020, and analyzed in detail for four countries (n = 417). Job satisfaction was measured with three questions: satisfaction with current job, quality of care in the workplace, and nursing profession. Nursing education related factors were satisfaction with nursing education program, level of study achievements, nursing as the 1st study choice, intention to stay in nursing, and generic nursing competence. The data were analyzed statistically using logistic regression. RESULTS: Most of the NGNs in the 10 countries were satisfied with their current job (88.3%), the quality of care (86.4%) and nursing profession (83.8%). Finnish, German, Lithuanian and Spanish NGNs' satisfaction with the nursing education program at graduation was statistically significantly associated with their job satisfaction, i.e., satisfaction with their current job, the quality of care, and the nursing profession. Moreover, NGNs who had fairly often or very often intention to stay in nursing at graduation were more satisfied with their current job, with the quality of care, and with the nursing profession compared with NGNs who had never or fairly seldom intention to stay in nursing at graduation. CONCLUSIONS: Nursing education plays a significant role in NGNs' job satisfaction one year after graduation, indicating the importance to start career planning already during nursing education. Both nursing education providers and healthcare organizations could plan in close collaboration a transition program for NGNs to ease the transition phase and thus increase the NGNs' job satisfaction and ultimately the high-quality care of the patients.

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