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1.
ACS Nano ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38739873

RESUMEN

van der Waals (vdW) magnetic materials, such as Cr2Ge2Te6 (CGT), show promise for memory and logic applications. This is due to their broadly tunable magnetic properties and the presence of topological magnetic features such as skyrmionic bubbles. A systematic study of thickness and oxidation effects on magnetic domain structures is important for designing devices and vdW heterostructures for practical applications. Here, we investigate thickness effects on magnetic properties, magnetic domains, and bubbles in oxidation-controlled CGT crystals. We find that CGT exposed to ambient conditions for 5 days forms an oxide layer approximately 5 nm thick. This oxidation leads to a significant increase in the oxidation state of the Cr ions, indicating a change in local magnetic properties. This is supported by real-space magnetic texture imaging through Lorentz transmission electron microscopy. By comparing the thickness-dependent saturation field of oxidized and pristine crystals, we find that oxidation leads to a nonmagnetic surface layer that is thicker than the oxide layer alone. We also find that the stripe domain width and skyrmionic bubble size are strongly affected by the crystal thickness in pristine crystals. These findings underscore the impact of thickness and surface oxidation on the properties of CGT, such as saturation field and domain/skyrmionic bubble size, and suggest a pathway for manipulating magnetic properties through a controlled oxidation process.

2.
Cureus ; 16(2): e55260, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38558609

RESUMEN

Lipedema, a chronic and painful disorder primarily affecting women without a definitive cure, has traditionally been managed with conservative therapy, notably complete decongestive therapy, across many countries. Recently, liposuction has been explored as a potential surgical treatment, prompting this study to evaluate its effectiveness as possibly the first-line therapy for lipedema. Through extensive literature searches in databases such as CrossRef, Web of Science, PubMed, and Google Scholar up to December 2023, and using the Newcastle-Ottawa Scale for quality assessment, the study selected seven studies for inclusion. Results showed significant post-operative improvements in spontaneous pain, edema, bruising, mobility, and quality of life among lipedema patients undergoing liposuction. However, over half of the patients still required conservative therapy after surgery. Despite these promising results, the study suggests caution due to lipedema's complexity, significant reliance on self-reported data, and limitations of the studies reviewed. Thus, while liposuction may offer symptomatic relief, it should be considered an adjunct, experimental therapy rather than a definitive cure, emphasizing the need for a comprehensive approach to care.

3.
Science ; 384(6693): 312-317, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38669572

RESUMEN

Electrostatic capacitors are foundational components of advanced electronics and high-power electrical systems owing to their ultrafast charging-discharging capability. Ferroelectric materials offer high maximum polarization, but high remnant polarization has hindered their effective deployment in energy storage applications. Previous methodologies have encountered problems because of the deteriorated crystallinity of the ferroelectric materials. We introduce an approach to control the relaxation time using two-dimensional (2D) materials while minimizing energy loss by using 2D/3D/2D heterostructures and preserving the crystallinity of ferroelectric 3D materials. Using this approach, we were able to achieve an energy density of 191.7 joules per cubic centimeter with an efficiency greater than 90%. This precise control over relaxation time holds promise for a wide array of applications and has the potential to accelerate the development of highly efficient energy storage systems.

4.
Int J Stroke ; : 17474930241246157, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38546172

RESUMEN

BACKGROUND AND OBJECTIVE: The Modified Rankin Scale (mRS) is a widely adopted scale for assessing stroke recovery. Despite limitations, the mRS has been adopted as primary outcome in most recent clinical acute stroke trials. Designed to be used by multidisciplinary clinical staff, the congruency of this scale is not consistent, which may lead to mistakes in clinical or research application. We aimed to develop and validate an interactive and automated digital tool for assessing the mRS-the iRankin. METHODS: A panel of five board-certified and mRS-trained vascular neurologists developed an automated flowchart based on current mRS literature. Two international experts were consulted on content and provided feedback on the prototype platform. The platform contained five vignettes and five real video cases, representing mRS grades 0-5. For validation, we invited neurological staff from six comprehensive stroke centers to complete an online assessment. Participants were randomized into two equal groups usual practice versus iRankin. The participants were randomly allocated in pairs for the congruency analysis. Weighted kappa (kw) and proportions were used to describe agreement. RESULTS: A total of 59 professionals completed the assessment. The kw was dramatically improved among nurses, 0.76 (95% confidence interval (CI) = 0.55-0.97) × 0.30 (0.07-0.67), and among vascular neurologists, 0.87 (0.72-1) × 0.82 (0.66-0.98). In the accuracy analysis, after the standard mRS values for the vignettes and videos were determined by a panel of experts, and considering each correct answer as equivalent to 1 point on a scale of 0-15, it revealed a higher mean of 10.6 (±2.2) in the iRankin group and 8.2 (±2.3) points in the control group (p = 0.02). In an adjusted analysis, the iRankin adoption was independently associated with the score of congruencies between reported and standard scores (beta coefficient = 2.22, 95% CI = 0.64-3.81, p = 0.007). CONCLUSION: The iRankin adoption led to a substantial or near-perfect agreement in all analyzed professional categories. More trials are needed to generalize our findings. Our user-friendly and free platform is available at https://www.irankinscale.com/.

5.
Int J Obes (Lond) ; 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38538853

RESUMEN

BACKGROUND: T-Lymphocyte activation is modulated by the adipokine leptin and serum concentrations of this hormone can be reduced with short-term calorie restriction. The aim of this study was to understand whether leptin per se is important in determining levels of T-lymphocyte activation in humans, by investigating whether the reduction in leptin concentration following calorie restriction is associated with a decrease in T-Lymphocyte activation in blood and adipose tissue. METHODS: Twelve men with overweight and obesity (age 35-55 years, waist circumference 95-115 cm) reduced their calorie intake by 50% for 3 consecutive days. Blood and subcutaneous adipose tissue were obtained for isolation of immune cells and cytokine analysis. CD4+ and CD8 + T-Lymphocytes were identified and characterised according to their expression of activation markers CD25 and CD69 by flow cytometry. RESULTS: Serum leptin was reduced by (mean ± SEM) 31 ± 16% (p < 0.001) following calorie restriction. The percentage of blood CD4 + CD25 + T-lymphocytes and level of CD25 expression on these lymphocytes were significantly reduced by 8 ± 10% (p = 0.016) and 8 ± 4% (p = 0.058), respectively. After calorie restriction, ex vivo leptin secretion from abdominal subcutaneous adipose tissue explants was not changed, and this corresponded with a lack of change in adipose tissue resident T-Lymphocyte activation. CONCLUSIONS: Serum leptin was reduced after calorie restriction and this was temporally associated with a reduction in activation of blood CD4 + CD25 + T-Lymphocytes. In abdominal subcutaneous adipose tissue, however, leptin secretion was unaltered, and there were no observed changes in adipose resident T-Lymphocyte activation.

6.
Nat Ecol Evol ; 8(4): 676-685, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38374185

RESUMEN

Habitat associations underpin species ecologies in high-diversity systems. Within tropical, shallow water coral reefs, the relationship between fishes and corals is arguably the most iconic and highly scrutinized. A strong relationship between fishes and reef-building hard corals is often assumed, a belief supported by studies that document the decline of reef fishes following coral loss. However, the extent of this relationship is often unclear, as evidenced by conflicting reports. Here we assess the strength of this ecological association by relying on literature that has surveyed both fishes and corals synchronously. We quantitatively synthesize 723 bivariate correlation coefficients (from 66 papers), published over 38 years, that relate fish metrics (abundance, biomass and species richness) with the percentage of hard coral cover. Remarkably, despite extensive variation, the pattern of association on a global scale reveals a predominantly positive, albeit weak (|r| < 0.4), correlation. Even for commonly hypothesized drivers of fish-coral associations, fish family and trophic group, associations were consistently weak. These findings question our assumptions regarding the strength and ubiquity of fish-coral associations, and caution against assuming a direct and omnipresent relationship between these two iconic animal groups.


Asunto(s)
Antozoos , Animales , Arrecifes de Coral , Ecosistema , Biomasa , Peces
7.
Int J Biol Macromol ; 263(Pt 1): 130292, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38382775

RESUMEN

The insertion of hydrophobic and hydrophilic chains in the chitosan molecule can improve its antibacterial activity, expanding its range of application in several areas of medical-pharmaceutical sciences. Thus, this work aimed to increase the antibacterial activity of chitosan through the modification reaction with phthalic anhydride (QF) and subsequent reaction with ethylenediamine (QFE). The chitosan and derivatives obtained were characterized by elemental analysis, 13C Nuclear Magnetic Resonance (13C NMR), X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetric Analysis (TG), where it was possible to prove the chemical modification. Both materials showed a greater antibacterial inhibitory effect against Gram-positive bacteria, Staphylococcus aureus, emphasizing antibacterial activity against Gram-negative bacteria, Escherichia coli, with values above 70 % of the inhibitory effect, which is a promising result. Assays with human fibroblast cells by the [3-(4,5-dimethylthiazolyl)-2,5-diphenyl tetrazolium (MTT)] bromide reduction test did not indicate toxicity in the materials. Thus, the derived materials showed promise for biomedical applications since they combined excellent antibacterial activity against gram-positive and gram-negative strains and did not show cytotoxicity.


Asunto(s)
Quitosano , Humanos , Quitosano/química , Anhídridos Ftálicos/farmacología , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/química , Espectroscopía Infrarroja por Transformada de Fourier , Escherichia coli , Etilenodiaminas/farmacología , Difracción de Rayos X
8.
Phys Chem Chem Phys ; 26(10): 8469-8487, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38410922

RESUMEN

Efficient surface passivation and toxic lead (Pb) are known obstacles to the photovoltaic application of perovskite-based solar cells. A possible solution for these problems is to use thin-films of two-dimensional (2D) perovskite-based materials and the replacement of Pb with alternative divalent cations (B); however, our atomistic understanding of the differences between (3D) three-dimensional and 2D perovskite-based materials is far from satisfactory. Herein, we report a systematic theoretical investigation based on ab initio density functional theory (DFT) calculations for both 3D MABX3 and the Ruddlesden-Popper 2D (BA)2(MA)B2X7 (B = Ge, Sn, Pb, and X = Cl, Br, I) compounds to investigate the differences (contrasts) in selected physical-chemical properties, i.e., structural parameters, energetic stability, electronic, and optical properties. We found an increased cation/anion charge separation because of the presence of organic spacers, which results in stronger Coulomb interactions in the inorganic framework, and hence, it enhances the cohesive energy (stability) within the inorganic layer. The inorganic layer constitutes the optically active region that contributes to the superior performance of perovskite-based solar cells. We quantified this effect by comparing the average electronic charges at the X sites in both 2D and 3D perovskites. This comparison is then correlated with variations in BX6-octahedron volumes, resulting in a monotonic relation. Moreover, the electronic structure characterization demonstrates that Ge-based systems present weakly sensitive band gaps to dimensionality due to a compensatory effect between Jahn-Teller distortions and quantum confinement. Lead-free GeI-, SnBr-, and SnI-based perovskites have DFT band gaps closer to the optimal value used in photovoltaic applications. Finally, as expected, the 2D systems absorption coefficients show pronounced anisotropy.

9.
Inflammation ; 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38329636

RESUMEN

Neutrophilic asthma is generally defined by poorly controlled symptoms and high levels of neutrophils in the lungs. Short-chain fatty acids (SCFAs) are proposed as nonpharmacological therapy for allergic asthma, but their impact on the neutrophilic asthma lacks evidence. SCFAs regulate immune cell responses and impact the inflammasome NLRP3, a potential pharmacological target for neutrophilic asthma. Here, we explored the capacity of SCFAs to mitigate murine-induced neutrophilic asthma and the contribution of NLRP3 to this asthma. The objective of this study is to analyze whether SCFAs can attenuate lung inflammation and tissue remodeling in murine neutrophilic asthma and NLRP3 contribution to this endotype. Wild-type (WT) C57BL6 mice orotracheally received 10 µg of HDM (house dust mite) in 80 µL of saline on days 0, 6-10. To explore SCFAs, each HDM group received 200 mM acetate, propionate, or butyrate. To explore NLRP3, Nlrp3 KO mice received the same protocol of HDM. On the 14th day, after euthanasia, bronchoalveolar lavage fluid (BALF) and lungs were collected to evaluate cellularity, inflammatory cytokines, and tissue remodeling. HDM group had increased BALF neutrophil influx, TNF-α, IFN-γ, IL-17A, collagen deposition, and mucus secretion compared to control. SCFAs distinctively attenuate lung inflammation. Only features of tissue remodeling were Nlrp3-dependent such as collagen deposition, mucus secretion, active TGF-ß cytokine, and IMs CD206+. SCFAs greatly decreased inflammatory cytokines and tissue remodeling. Only tissue remodeling was dependent on NLRP3. It reveals the potential of SCFAs to act as an additional therapy to mitigate neutrophilic asthma and the NLRP3 contribution to asthma.

10.
ACS Catal ; 14(1): 406-417, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38205022

RESUMEN

The oxygen species on Ag catalysts and reaction mechanisms for ethylene epoxidation and ethylene combustion continue to be debated in the literature despite decades of investigation. Fundamental details of ethylene oxidation by supported Ag/α-Al2O3 catalysts were revealed with the application of high-angle annular dark-field-scanning transmission electron microscopy-energy-dispersive X-ray spectroscopy (HAADF-STEM-EDS), in situ techniques (Raman, UV-vis, X-ray diffraction (XRD), HS-LEIS), chemical probes (C2H4-TPSR and C2H4 + O2-TPSR), and steady-state ethylene oxidation and SSITKA (16O2 → 18O2 switch) studies. The Ag nanoparticles are found to carry a considerable amount of oxygen after the reaction. Density functional theory (DFT) calculations indicate the oxidative reconstructed p(4 × 4)-O-Ag(111) surface is stable relative to metallic Ag(111) under the relevant reaction environment. Multiple configurations of reactive oxygen species are present, and their relevant concentrations depend on treatment conditions. Selective ethylene oxidation to EO proceeds with surface Ag4-O2* species (dioxygen species occupying an oxygen site on a p(4 × 4)-O-Ag(111) surface) only present after strong oxidation of Ag. These experimental findings are strongly supported by the associated DFT calculations. Ethylene epoxidation proceeds via a Langmuir-Hinshelwood mechanism, and ethylene combustion proceeds via combined Langmuir-Hinshelwood (predominant) and Mars-van Krevelen (minor) mechanisms.

11.
Psychol Rep ; : 332941241227150, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38291607

RESUMEN

In this paper, we conducted a meta-analytic review to examine the impact of social presence on individuals' performance on the Stroop task, shedding light on the cognitive processes underlying social facilitation. We followed PRISMA guidelines to identify and include 33 relevant studies in a multivariate random-effects meta-analysis. Our results show that social presence reliably modulates Stroop interference (a measure of cognitive control); specifically, participants exhibit lower Stroop interference when performing the task in the presence of others compared to performing it in isolation. We also found that the strength of the effect varies depending on the type of social presence: it is stronger with an attentive audience compared to an inattentive one, and null with an evaluative audience. Additionally, different features of the Stroop task itself moderate the effect; the effect is stronger for the classic version of the task compared to the semantic version, and for experiments that use mixed within-block trials compared to those with homogenous blocks. We also observed a negative relationship between the number of trials and the magnitude of the effect. Overall, these findings provide insights into the mechanisms by which the presence of others affects performance on the Stroop task, and how they align with social facilitation theories.

12.
ACS Nano ; 18(4): 3286-3294, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38227802

RESUMEN

The controlled design of bimetallic nanoparticles (BNPs) is a key goal in tailoring their catalytic properties. Recently, biomimetic pathways demonstrated potent control over the distribution of different metals within BNPs, but a direct understanding of the peptide effect on the compositional distribution at the interparticle and intraparticle levels remains lacking. We synthesized two sets of PtAu systems with two peptides and correlated their structure, composition, and distributions with the catalytic activity. Structural and compositional analyses were performed by a combined machine learning-assisted refinement of X-ray absorption spectra and Z-contrast measurements by scanning transmission electron microscopy. The difference in the catalytic activities between nanoparticles synthesized with different peptides was attributed to the details of interparticle distribution of Pt and Au across these markedly heterogeneous systems, comprising Pt-rich, Au-rich, and Au core/Pt shell nanoparticles. The total amount of Pt in the shells of the BNPs was proposed to be the key catalytic activity descriptor. This approach can be extended to other systems of metals and peptides to facilitate the targeted design of catalysts with the desired activity.

13.
J Sleep Res ; : e14154, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38286415

RESUMEN

Gender and age are well-established determinants of health and sleep health that influence overall health, which also often varies by gender and age. Sleep architecture is an important component of sleep health. The goal of this analysis was to examine whether associations between age and sleep stages differ by gender in the absence of moderate-severe obstructive sleep apnea (OSA) in a rural setting in Brazil. This study conducted polysomnography recordings in the Baependi Heart Study, a cohort of Brazilian adults. Our sample included 584 women and 309 men whose apnea-hypopnea index was ≤15 events/h. We used splines to distinguish non-linear associations between age, total sleep time, wake after sleep onset (WASO), N2, N3, and rapid-eye-movement sleep. The mean (standard deviation; range) age was 47 (14; 18-89) years. All sleep outcomes were associated with age. Compared to men, women had more N3 sleep and less WASO after adjusting for age. Model-based comparisons between genders at specific ages showed statistically higher mean WASO for men at ages 60 (+13.6 min) and 70 years (+19.5 min) and less N3 for men at ages 50 (-13.2 min), 60 (-19.0 min), and 70 years (-19.5 min) but no differences at 20, 30, 40 or 80 years. The other sleep measures did not differ by gender at any age. Thus, even in the absence of moderate-severe OSA, sleep architecture was associated with age across adulthood, and there were gender differences in WASO and N3 at older ages in this rural community.

14.
J Racial Ethn Health Disparities ; 11(2): 1024-1032, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37052798

RESUMEN

The mechanisms underlying racial inequities in uncontrolled hypertension have been limited to individual factors. We investigated racial inequities in uncontrolled hypertension and the explanatory role of economic segregation in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). All 3897 baseline participants with hypertension (2008-2010) were included. Uncontrolled hypertension (SBP ≥ 140 mmHg or DBP ≥ 90 mmHg), self-reported race (White/Brown/Black people), and neighborhood economic segregation (low/medium/high) were analyzed cross-sectionally. We used decomposition analysis, which describes how much a disparity would change (disparity reduction; explained portion) and remain (disparity residual; unexplained portion) upon removing racial differences in economic segregation (i.e., if Black people had the distribution of segregation of White people, how much we would expect uncontrolled hypertension to decrease among Black people). Age- and gender-adjusted prevalence of uncontrolled hypertension (39.0%, 52.6%, and 54.2% for White, Brown, and Black participants, respectively) remained higher for Black and Brown vs White participants, regardless of economic segregation. Uncontrolled hypertension showed a dose-response pattern with increasing segregation levels for White but not for Black and Brown participants. After adjusting for age, gender, education, and study center, unexplained portion (disparity residual) of race on uncontrolled hypertension was 18.2% (95% CI 13.4%; 22.9%) for Black vs White participants and 12.6% (8.2%; 17.1%) for Brown vs White participants. However, explained portion (disparity reduction) through economic segregation was - 2.1% (- 5.1%; 1.3%) for Black vs White and 0.5% (- 1.7%; 2.8%) for Brown vs White participants. Although uncontrolled hypertension was greater for Black and Brown vs White people, racial inequities in uncontrolled hypertension were not explained by economic segregation.


Asunto(s)
Hipertensión , Segregación Residencial , Adulto , Humanos , Brasil/epidemiología , Estudios Longitudinales , Población Blanca , Población Negra , Grupos Raciales
15.
Dalton Trans ; 53(2): 746-752, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38086661

RESUMEN

The presented simulation protocol provides a solid foundation for exploring two-dimensional materials. Taking the TiBr2 2H monolayer as an example, this material displays promising TMDC-like optical and excitonic properties, making it an excellent candidate for optoelectronic and valleytronic applications. The direct band gap semiconductor (1.19 eV) is both structurally and thermodynamically stable, with spin-orbit coupling effects revealing a broken mirror symmetry in the K and K' valleys of the band structure, as confirmed by opposite values of the Berry curvature. A direct and bright exciton ground state was found, with an exciton binding energy of 0.56 eV. The study also revealed an optical helicity selection rule, suggesting selectivity in the valley excitation by specific circular light polarizations.

16.
J Infect Dis ; 229(4): 1189-1199, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-37740551

RESUMEN

BACKGROUND: High-resolution metabolomics (HRM) is an innovative tool to study challenging infectious diseases like leprosy, where the pathogen cannot be grown with standard methods. Here, we use HRM to better understand associations between disease manifestations, nutrition, and host metabolism. METHODS: From 2018 to 2019, adults with leprosy and controls were recruited in Minas Gerais, Brazil. Plasma metabolites were detected using an established HRM workflow and characterized by accurate mass, mass to charge ratio m/z and retention time. The mummichog informatics package compared metabolic pathways between cases and controls and between multibacillary (MB) and paucibacillary (PB) leprosy. Additionally, select individual metabolites were quantified and compared. RESULTS: Thirty-nine cases (62% MB and 38% PB) and 25 controls were enrolled. We found differences (P < .05) in several metabolic pathways, including fatty acid metabolism, carnitine shuttle, retinol, vitamin D3, and C-21 steroid metabolism, between cases and controls with lower retinol and associated metabolites in cases. Between MB and PB, leukotrienes, prostaglandins, tryptophan, and cortisol were all found to be lower in MB (P < .05). DISCUSSION: Metabolites associated with several nutrient-related metabolic pathways appeared differentially regulated in leprosy, especially MB versus PB. This pilot study demonstrates the metabolic interdependency of these pathways, which may play a role in the pathophysiology of disease.


Asunto(s)
Lepra , Micronutrientes , Adulto , Humanos , Ácidos Grasos , Proyectos Piloto , Vitamina A , Mycobacterium leprae
17.
Sleep ; 47(1)2024 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-37658822

RESUMEN

STUDY OBJECTIVES: People with diabetes and prediabetes are more likely to have sleep-disordered breathing (SDB), but few studies examined sleep architecture in people with diabetes or prediabetes in the absence of moderate-severe SDB, which was the aim of our cross-sectional study. METHODS: This cross-sectional sample is from the Baependi Heart Study, a family-based cohort of adults in Brazil. About 1074 participants underwent at-home polysomnography (PSG). Diabetes was defined as fasting glucose >125 mg/dL or HbA1c > 6.4 mmol/mol or taking diabetic medication, and prediabetes was defined as HbA1c ≥ 5.7 & <6.5 mmol/mol or fasting glucose ≥ 100 & ≤125 mg/dl. We excluded participants with an apnea-hypopnea index (AHI) ≥ 30 in primary analyses and ≥ 15 in secondary analysis. We compared sleep stages among the 3 diabetes groups (prediabetes, diabetes, neither). RESULTS: Compared to those without diabetes, we found shorter REM duration for participants with diabetes (-6.7 min, 95%CI -13.2, -0.1) and prediabetes (-5.9 min, 95%CI -10.5, -1.3), even after adjusting for age, gender, BMI, and AHI. Diabetes was also associated with lower total sleep time (-13.7 min, 95%CI -26.8, -0.6), longer slow-wave sleep (N3) duration (+7.6 min, 95%CI 0.6, 14.6) and higher N3 percentage (+2.4%, 95%CI 0.6, 4.2), compared to those without diabetes. Results were similar when restricting to AHI < 15. CONCLUSIONS: People with diabetes and prediabetes had less REM sleep than people without either condition. People with diabetes also had more N3 sleep. These results suggest that diabetes and prediabetes are associated with differences in sleep architecture, even in the absence of moderate-severe sleep apnea.


Asunto(s)
Diabetes Mellitus , Estado Prediabético , Síndromes de la Apnea del Sueño , Adulto , Humanos , Estudios Transversales , Estado Prediabético/complicaciones , Hemoglobina Glucada , Sueño REM , Glucosa
18.
J Hypertens ; 42(2): 301-307, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37796232

RESUMEN

AIM: Leg blood pressure (BP) measurement is needed when arm BP evaluation is not feasible, and calf BP, especially when measured in standing position, may have greater association with cardiovascular remodeling than arm BP. This study evaluated the relationship between calf and arm BP, and investigated whether calf BP would be superior to arm BP in predicting increased arterial stiffness [pulse wave velocity (PWV) > 10 m/s]. METHODS: We evaluated clinical and laboratory characteristics, BP measurements, and PWV in 1397 individuals resident in Baependi, Brazil, between 2017 and 2019. Arm BP was measured in the seated and supine positions while calf BP was measured in supine and standing positions using digital oscillometric devices. Carotid-femoral PWV was measured using a noninvasive mechanotransducer. RESULTS: The sample had 62.7% females, age = 48.1 ±â€Š15.4 years and 8.4% with PWV >10 m/s. Results of linear regression analysis showed that BP values of 140/90 mmHg measured in the arm in supine and seated position were equivalent to calf supine BP values of 164/81 mmHg and 166/78 mmHg and calf standing BP values of 217/137 mmHg and 221/137 mmHg, respectively. Calf-arm BP differences were associated with age, glomerular filtration rate, body mass index, smoking, low-density lipoprotein-cholesterol, diabetes and height. Furthermore, stepwise logistic regression analysis revealed that arm supine systolic BP, but not calf BP measurements, was independently associated with increased arterial stiffness. CONCLUSION: Thresholds of ≈165/80 mmHg and ≈220/135 mmHg could be used for diagnosing hypertension when only calf measurements in supine and standing positions, respectively, are available. Conversely, calf BP was not superior to arm BP in predicting increased arterial stiffness.


Asunto(s)
Hipertensión , Rigidez Vascular , Femenino , Humanos , Adulto , Persona de Mediana Edad , Masculino , Presión Sanguínea/fisiología , Análisis de la Onda del Pulso , Rigidez Vascular/fisiología , Pierna
19.
Circulation ; 149(2): 107-123, 2024 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-37929589

RESUMEN

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is characterized by unexplained left ventricular hypertrophy and is classically caused by pathogenic or likely pathogenic variants (P/LP) in genes encoding sarcomere proteins. Not all subclinical variant carriers will manifest clinically overt disease because penetrance (proportion of sarcomere or sarcomere-related P/LP variant carriers who develop disease) is variable, age dependent, and not reliably predicted. METHODS: A systematic search of the literature was performed. We used random-effects generalized linear mixed model meta-analyses to contrast the cross-sectional prevalence and penetrance of sarcomere or sarcomere-related genes in 2 different contexts: clinically-based studies on patients and families with HCM versus population or community-based studies. Longitudinal family/clinical studies were additionally analyzed to investigate the rate of phenotypic conversion from subclinical to overt HCM during follow-up. RESULTS: In total, 455 full-text manuscripts and articles were assessed. In family/clinical studies, the prevalence of sarcomere variants in patients diagnosed with HCM was 34%. The penetrance across all genes in nonproband relatives carrying P/LP variants identified during cascade screening was 57% (95% CI, 52%-63%), and the mean age at HCM diagnosis was 38 years (95% CI, 36%-40%). Penetrance varied from ≈32% for MYL3 (myosin light chain 3) to ≈55% for MYBPC3 (myosin-binding protein C3), ≈60% for TNNT2 (troponin T2) and TNNI3 (troponin I3), and ≈65% for MYH7 (myosin heavy chain 7). Population-based genetic studies demonstrate that P/LP sarcomere variants are present in the background population but at a low prevalence of <1%. The penetrance of HCM in incidentally identified P/LP variant carriers was also substantially lower at ≈11%, ranging from 0% in Atherosclerosis Risk in Communities to 18% in UK Biobank. In longitudinal family studies, the pooled phenotypic conversion across all genes was 15% over an average of ≈8 years of follow-up, starting from a mean of ≈16 years of age. However, short-term gene-specific phenotypic conversion varied between ≈12% for MYBPC3 and ≈23% for MYH7. CONCLUSIONS: The penetrance of P/LP variants is highly variable and influenced by currently undefined and context-dependent genetic and environmental factors. Additional longitudinal studies are needed to improve our understanding of true lifetime penetrance in families and in the community and to identify drivers of the transition from subclinical to overt HCM.


Asunto(s)
Cardiomiopatía Hipertrófica , Humanos , Adulto , Penetrancia , Mutación , Estudios Transversales , Linaje , Cardiomiopatía Hipertrófica/diagnóstico , Cardiomiopatía Hipertrófica/epidemiología , Cardiomiopatía Hipertrófica/genética , Troponina T/genética
20.
J Hypertens ; 42(1): 129-135, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37728130

RESUMEN

BACKGROUND: High blood pressure (BP) increases carotid intima-media thickness (CIMT). On the other hand, it is not clear whether the vascular abnormalities reflected in high CIMT may predict incident hypertension. The present study aims to investigate the association between CIMT and incident hypertension after 4 years of follow-up in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil), a multiethnic sample of middle-aged adults from six Brazilian cities. METHODS: We analyzed data from 6682 ELSA-Brasil participants (aged 35-74) without hypertension and with complete CIMT data at baseline. After 4 years of follow-up, we describe hypertension incidence, stratifying the sample according to age, sex, and race-specific CIMT quartiles. We also built crude and adjusted Poisson regression models to analyze the association between mean and maximal CIMT values and incident hypertension. RESULTS: We found incident hypertension in 987 (14.8%) participants. According to mean CIMT quartile groups, hypertension incidence varied from 10.2% (first quartile group) to 22.4% (fourth quartile group; P for trend <0.001). In fully adjusted models, 0.1 mm increments in mean CIMT values were associated with a 16% [relative risk (RR):1.16; 95% confidence interval (95% CI) 1.10-1.21; P  < 0.001] higher risk of incident hypertension, respectively. Results were similar when maximal CIMT values were considered instead of mean CIMT values. CONCLUSION: CIMT values at baseline strongly predicted incident hypertension after 4 years of follow-up in this large multiethnic cohort. This highlights the relationship between CIMT and BP and may provide important insights into the significance of this ultrasound measurement.


Asunto(s)
Grosor Intima-Media Carotídeo , Hipertensión , Persona de Mediana Edad , Adulto , Humanos , Estudios Longitudinales , Brasil/epidemiología , Factores de Riesgo , Hipertensión/epidemiología
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