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1.
EMBO Rep ; 24(6): e56818, 2023 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-37042686

RESUMEN

Immature dendritic cells (iDCs) migrate in microenvironments with distinct cell and extracellular matrix densities in vivo and contribute to HIV-1 dissemination and mounting of antiviral immune responses. Here, we find that, compared to standard 2D suspension cultures, 3D collagen as tissue-like environment alters iDC properties and their response to HIV-1 infection. iDCs adopt an elongated morphology with increased deformability in 3D collagen at unaltered activation, differentiation, cytokine secretion, or responsiveness to LPS. While 3D collagen reduces HIV-1 particle uptake by iDCs, fusion efficiency is increased to elevate productive infection rates due to elevated cell surface exposure of the HIV-1-binding receptor DC-SIGN. In contrast, 3D collagen reduces HIV transfer to CD4 T cells from iDCs. iDC adaptations to 3D collagen include increased pro-inflammatory cytokine production and reduced antiviral gene expression in response to HIV-1 infection. Adhesion to a 2D collagen matrix is sufficient to increase iDC deformability, DC-SIGN exposure, and permissivity to HIV-1 infection. Thus, mechano-physical cues of 2D and 3D tissue-like collagen environments regulate iDC function and shape divergent roles during HIV-1 infection.


Asunto(s)
Infecciones por VIH , VIH-1 , Humanos , Citocinas/metabolismo , Colágeno/metabolismo , Antivirales , Células Dendríticas
2.
J Infect Dis ; 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39374370

RESUMEN

Reduced deformability of both infected and uninfected red blood cells (RBC) contributes to pathogenesis in falciparum malaria. Whole blood RBC-deformability is not well-characterised in vivax malaria. We used a laser-assisted optical rotational cell analyzer to measure the RBC deformability in fresh whole blood from Malaysian patients with vivax malaria (n=25). Deformability of whole blood RBC, the vast majority of which were uninfected, was reduced in vivax malaria compared to controls (n=15), though not to the same degree as in falciparum malaria (n=90). Reduced RBC-deformability may contribute to the pathogenesis of vivax malaria, including splenic retention of uninfected RBC.

3.
J Cell Physiol ; 239(3): e30958, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36748950

RESUMEN

Intracellular signaling mechanisms in red blood cells (RBCs) involve various protein kinases and phosphatases and enable rapid adaptive responses to hypoxia, metabolic requirements, oxidative stress, or shear stress by regulating the physiological properties of the cell. Protein phosphorylation is a ubiquitous mechanism for intracellular signal transduction, volume regulation, and cytoskeletal organization in RBCs. Spectrin-based cytoskeleton connects integral membrane proteins, band 3 and glycophorin C to junctional proteins, ankyrin and Protein 4.1. Phosphorylation leads to a conformational change in the protein structure, weakening the interactions between proteins in the cytoskeletal network that confers a more flexible nature for the RBC membrane. The structural organization of the membrane and the cytoskeleton determines RBC deformability that allows cells to change their ability to deform under shear stress to pass through narrow capillaries. The shear stress sensing mechanisms and oxygenation-deoxygenation transitions regulate cell volume and mechanical properties of the membrane through the activation of ion transporters and specific phosphorylation events mediated by signal transduction. In this review, we summarize the roles of Protein kinase C, cAMP-Protein kinase A, cGMP-nitric oxide, RhoGTPase, and MAP/ERK pathways in the modulation of RBC deformability in both healthy and disease states. We emphasize that targeting signaling elements may be a therapeutic strategy for the treatment of hemoglobinopathies or channelopathies. We expect the present review will provide additional insights into RBC responses to shear stress and hypoxia via signaling mechanisms and shed light on the current and novel treatment options for pathophysiological conditions.


Asunto(s)
Eritrocitos , Proteínas de la Membrana , Humanos , Fosforilación , Eritrocitos/metabolismo , Proteínas de la Membrana/metabolismo , Transducción de Señal , Hipoxia/metabolismo
4.
Small ; 20(7): e2303962, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37789502

RESUMEN

Previous on-chip technologies for characterizing the cellular mechanical properties often suffer from a low throughput and limited sensitivity. Herein, an inertial multi-force deformability cytometry (IMFDC) is developed for high-throughput, high-accuracy, and high-applicability tumor cell mechanotyping. Three different deformations, including shear deformations and stretch deformations under different forces, are integrated with the IMFDC. The 3D inertial focusing of cells enables the cells to deform by an identical fluid flow, and 10 parameters, such as cell area, perimeter, deformability, roundness, and rectangle deformability, are obtained in three deformations. The IMFDC is able to evaluate the deformability of different cells that are sensitive to different forces on a single chip, demonstrating the high applicability of the IMFDC in analyzing different cell lines. In identifying cell types, the three deformations exhibit different mechanical responses to cells with different sizes and deformability. A discrimination accuracy of ≈93% for both MDA-MB-231 and MCF-10A cells and a throughput of ≈500 cells s-1 can be achieved using the multiple-parameters-based machine learning model. Finally, the mechanical properties of metastatic tumor cells in pleural and peritoneal effusions are characterized, enabling the practical application of the IMFDC in clinical cancer diagnosis.


Asunto(s)
Técnicas Analíticas Microfluídicas , Neoplasias , Humanos , Fenómenos Mecánicos , Citometría de Flujo
5.
Small ; : e2403371, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39032159

RESUMEN

The production and application of materials are evolving towards the low-dimensional micro-nano scale. Nevertheless, the fabrication of micron-scale alloy fibers remains a challenge. Herein, a novel Ni-Co-Cr-Fe-Mo high-entropy alloy (HEA) fiber with a cold-drawn reduction rate of 99.9995% and a strain (ɛ) of 12.19 is presented without requiring intermediate annealing. The exceptional deformation strain of 11.62 within the fiber leads to extraordinary tensile strengths of 2.8 GPa at room temperature and 3.6 GPa at 123 K. The in-depth investigation of the microstructure of fibers has revealed the cold drawing deformation mechanisms mediated by the synergistic effects of plane defects. Specifically, various geometrically necessary dislocation interfaces, such as dislocation walls and microbands, along with deformation twins and long-period 9R structures, form in response to external stress when ɛ≤2.7. As the strain increases, the saturated layered structure emerges and progressively evolves into a 3D equiaxed crystal. Moreover, the formation and evolution of the 9R structure (i.e., the migration of incoherent twin boundaries), coupled with the interaction of partial dislocations and the role of deformation twins, are crucial factors determining the fiber's plastic response. This work provides a novel approach to discovering new high-strength metallic fibers with excellent deformability through plane defects engineering.

6.
Blood Cells Mol Dis ; 109: 102881, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39151259

RESUMEN

Recent evidence suggests that systemic conditions, particularly those associated with inflammation, can affect erythrocyte deformability in the absence of haematological conditions. In this exploratory study, we investigated the relationship between systemic inflammatory status and erythrocyte deformability (using osmotic gradient ektacytometry) in a heterogenous study population consisting of individuals with no medical concerns, chronic conditions, and acute illness, providing a wide range of systemic inflammation severity. 22 participants were included in a prospective observational study. Maximum Elongation Index (EImax) in ektacytometry served as the readout for erythrocyte deformability. Inflammatory status was assessed using C-reactive protein (CRP) and self-reported symptoms associated with inflammatory activation (Sickness Questionnaire Scores, SicknessQ). In a univariate linear regression, both CRP and SicknessQ scores significantly predicted EImax (CRP: F(1,20) = 7.751, p < 0.05 (0.011), R2 = 0.279; SicknessQ: F(1,18) = 4.831, p < 0.05 (0.041), R2 = 0.212). Sensitivity analyses with multivariable linear regression correcting for age showed concordant findings. Results suggest a linear relationship between erythrocyte deformability and biochemical and clinical markers of systemic inflammation. Replication of findings in a larger study, and mechanisms and clinical consequences need further in investigation.


Asunto(s)
Proteína C-Reactiva , Deformación Eritrocítica , Inflamación , Humanos , Inflamación/sangre , Masculino , Femenino , Persona de Mediana Edad , Proteína C-Reactiva/análisis , Adulto , Estudios Prospectivos , Anciano , Biomarcadores/sangre , Eritrocitos/metabolismo , Eritrocitos/patología , Modelos Lineales
7.
Artículo en Inglés | MEDLINE | ID: mdl-39297974

RESUMEN

Cell deformability of all major blood cell types is increased in depressive disorders (DD). Furthermore, impaired glucocorticoid secretion is associated with DD, as well as depressive symptoms in general and known to alter cell mechanical properties. Nevertheless, there are no longitudinal studies examining accumulated glucocorticoid output and depressive symptoms regarding cell deformability. The aim of the present study was to investigate, whether depressive symptoms predict cell deformability one year later and whether accumulated hair glucocorticoids mediate this relationship. In 136 individuals (nfemale = 100; Mage = 46.72, SD = 11.28; age range = 20-65), depressive symptoms (PHQ-9) and hair glucocorticoids (cortisol and cortisone) were measured at time point one (T1), while one year later (T2) both depressive symptoms and hair glucocorticoids were reassessed. Additionally, cell deformability of peripheral blood cells was assessed at T2. Depression severity at T1 predicted higher cell deformability in monocytes and lymphocytes at T2. Accumulated hair cortisol and cortisone concentrations from T1 and T2 were not associated with higher cell deformability and further did not mediate the relationship between depressive symptoms and cell deformability. Elevated depressive symptomatology in a population based sample is longitudinally associated with higher immune cell deformability, while long-term integrated glucocorticoid levels seem not to be implicated in the underlying mechanism.

8.
Artículo en Inglés | MEDLINE | ID: mdl-39231863

RESUMEN

Treatments with different antithrombotic agents can affect micro-rheological variables, such as red blood cell (RBC) deformability and aggregation. Since the effect of dual antiplatelet and anticoagulant (APAC) treatment on micro-rheology is unknown, we aimed to investigate the effect of different intravenous doses of APAC on hematological and micro-rheological variables in a porcine model. Two groups were formed (APAC group, Control group), and blood was collected from the animals at preset intervals. Hematological variables, RBC deformability, and aggregation were measured. We observed an improvement in the RBC deformability measured at a low shear stress range (< 3 Pa). However, after both doses, a decrease in the maximal elongation index of RBC values occurred in the APAC group. RBC aggregation increased after APAC bolus dose, while it gradually and dose-dependently decreased. Supposedly, the improvement in RBC deformability that was observed at a lower shear rate could facilitate aggregation. Administration of APAC and unfractionated heparin (UFH) caused comparable changes in hematological and hemorheological variables. Signs of thrombosis or bleeding did not occur. APAC and UFH had comparable micro-rheological effects.

9.
Cell Mol Life Sci ; 80(11): 316, 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37801090

RESUMEN

Nuclear deformability plays a critical role in cell migration. During this process, the remodeling of internal components of the nucleus has a direct impact on DNA damage and cell behavior; however, how persistent migration promotes nuclear changes leading to phenotypical and functional consequences remains poorly understood. Here, we described that the persistent migration through physical barriers was sufficient to promote permanent modifications in migratory-altered cells. We found that derived cells from confined migration showed changes in lamin B1 localization, cell morphology and transcription. Further analysis confirmed that migratory-altered cells showed functional differences in DNA repair, cell response to chemotherapy and cell migration in vivo homing experiments. Experimental modulation of actin polymerization affected the redistribution of lamin B1, and the basal levels of DNA damage in migratory-altered cells. Finally, since major nuclear changes were present in migratory-altered cells, we applied a multidisciplinary biochemical and biophysical approach to identify that confined conditions promoted a different biomechanical response of the nucleus in migratory-altered cells. Our observations suggest that mechanical compression during persistent cell migration has a role in stable nuclear and genomic alterations that might handle the genetic instability and cellular heterogeneity in aging diseases and cancer.


Asunto(s)
Leucemia , Neoplasias , Humanos , Estrés Mecánico , Movimiento Celular , Reparación del ADN , Leucemia/genética , Núcleo Celular/fisiología
10.
Proc Natl Acad Sci U S A ; 118(15)2021 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-33876759

RESUMEN

The sequence-dependent structure and deformability of DNA play a major role for binding of proteins and regulation of gene expression. So far, most efforts to model DNA flexibility are based on unimodal harmonic stiffness models at base-pair resolution. However, multimodal behavior due to distinct conformational substates also contributes significantly to the conformational flexibility of DNA. Moreover, these local substates are correlated to their nearest-neighbor substates. A description for DNA elasticity which includes both multimodality and nearest-neighbor coupling has remained a challenge, which we solve by combining our multivariate harmonic approximation with an Ising model for the substates. In a series of applications to DNA fluctuations and protein-DNA complexes, we demonstrate substantial improvements over the unimodal stiffness model. Furthermore, our multivariate Ising model reveals a mechanical destabilization for adenine (A)-tracts to undergo nucleosome formation. Our approach offers a wide range of applications to determine sequence-dependent deformation energies of DNA and to investigate indirect readout contributions to protein-DNA recognition.


Asunto(s)
ADN/química , Modelos Teóricos , Conformación de Ácido Nucleico , Animales , ADN/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , Humanos , Simulación de Dinámica Molecular , Nucleosomas/química , Nucleosomas/metabolismo , Unión Proteica
11.
Neurocrit Care ; 41(2): 479-488, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38448744

RESUMEN

BACKGROUND: Today, invasive intracranial pressure (ICP) measurement remains the standard, but its invasiveness limits availability. Here, we evaluate a novel ultrasound-based optic nerve sheath parameter called the deformability index (DI) and its ability to assess ICP noninvasively. Furthermore, we ask whether combining DI with optic nerve sheath diameter (ONSD), a more established parameter, results in increased diagnostic ability, as compared to using ONSD alone. METHODS: We prospectively included adult patients with traumatic brain injury with invasive ICP monitoring, which served as the reference measurement. Ultrasound images and videos of the optic nerve sheath were acquired. ONSD was measured at the bedside, whereas DI was calculated by semiautomated postprocessing of ultrasound videos. Correlations of ONSD and DI to ICP were explored, and a linear regression model combining ONSD and DI was compared to a linear regression model using ONSD alone. Ability of the noninvasive parameters to distinguish dichotomized ICP was evaluated using receiver operating characteristic curves, and a logistic regression model combining ONSD and DI was compared to a logistic regression model using ONSD alone. RESULTS: Forty-four ultrasound examinations were performed in 26 patients. Both DI (R = - 0.28; 95% confidence interval [CI] R < - 0.03; p = 0.03) and ONSD (R = 0.45; 95% CI R > 0.23; p < 0.01) correlated with ICP. When including both parameters in a combined model, the estimated correlation coefficient increased (R = 0.51; 95% CI R > 0.30; p < 0.01), compared to using ONSD alone, but the model improvement did not reach statistical significance (p = 0.09). Both DI (area under the curve [AUC] 0.69, 95% CI 0.53-0.83) and ONSD (AUC 0.72, 95% CI 0.56-0.86) displayed ability to distinguish ICP dichotomized at ICP ≥ 15 mm Hg. When using both parameters in a combined model, AUC increased (0.80, 95% CI 0.63-0.90), and the model improvement was statistically significant (p = 0.02). CONCLUSIONS: Combining ONSD with DI holds the potential of increasing the ability of optic nerve sheath parameters in the noninvasive assessment of ICP, compared to using ONSD alone, and further study of DI is warranted.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Presión Intracraneal , Nervio Óptico , Ultrasonografía , Humanos , Nervio Óptico/diagnóstico por imagen , Nervio Óptico/fisiopatología , Masculino , Presión Intracraneal/fisiología , Femenino , Adulto , Persona de Mediana Edad , Lesiones Traumáticas del Encéfalo/diagnóstico por imagen , Lesiones Traumáticas del Encéfalo/fisiopatología , Estudios Prospectivos , Hipertensión Intracraneal/diagnóstico por imagen , Hipertensión Intracraneal/fisiopatología , Hipertensión Intracraneal/diagnóstico , Anciano , Adulto Joven
12.
J Liposome Res ; 34(1): 88-96, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37337884

RESUMEN

Upon in vivo administration of nanoparticles, a protein corona forms on their surface and affects their half-life in circulation, biodistribution properties, and stability; in turn, the composition of the protein corona depends on the physico-chemical properties of the nanoparticles. We have previously observed lipid composition-dependent in vitro and in vivo microRNA delivery from lipid nanoparticles. Here, we carried out an extensive physico-chemical characterisation to understand the role of the lipid composition on the in vivo fate of lipid-based nanoparticles. We used a combination of differential scanning calorimetry (DSC), membrane deformability measurements, isothermal titration calorimetry (ITC), and dynamic light scattering (DLS) to probe the interactions between the nanoparticle surface and bovine serum albumin (BSA) as a model protein. The lipid composition influenced membrane deformability, improved lipid intermixing, and affected the formation of lipid domains while BSA binding to the liposome surface was affected by the PEGylated lipid content and the presence of cholesterol. These findings highlight the importance of the lipid composition on the protein-liposome interaction and provide important insights for the design of lipid-based nanoparticles for drug delivery applications.


Asunto(s)
Nanopartículas , Corona de Proteínas , Liposomas , Distribución Tisular , Nanopartículas/química , Calorimetría , Albúmina Sérica Bovina/química , Lípidos
13.
Surg Innov ; : 15533506241290412, 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39370802

RESUMEN

OBJECTIVE: This systematic review investigates of Augmented Reality (AR) systems used in minimally invasive surgery of deformable organs, focusing on initial registration, dynamic tracking, and visualization. The objective is to acquire a comprehensive understanding of the current knowledge, applications, and challenges associated with current AR-techniques, aiming to leverage these insights for developing a dedicated AR pulmonary Video or Robotic Assisted Thoracic Surgery (VATS/RATS) workflow. METHODS: A systematic search was conducted within Embase, Medline (Ovid) and Web of Science on April 16, 2024, following the Preferred Reporting items for Systematic Reviews and Meta-Analyses (PRISMA). The search focused on intraoperative AR applications and intraoperative navigational purposes for deformable organs. Quality assessment was performed and studies were categorized according to initial registration and dynamic tracking methods. RESULTS: 33 articles were included, of which one involved pulmonary surgery. Studies used both manual and (semi-) automatic registration methods, established through anatomical landmark-based, fiducial-based, or surface-based techniques. Diverse outcome measures were considered, including surgical outcomes and registration accuracy. The majority of studies that reached an registration accuracy below 5 mm applied surface-based registration. CONCLUSIONS: AR can potentially aid surgeons with real-time navigation and decision making during anatomically complex minimally invasive procedures. Future research for pulmonary applications should focus on exploring surface-based registration methods, considering their non-invasive, marker-less nature, and promising accuracy. Additionally, vascular-labeling-based methods are worth exploring, given the importance and relative stability of broncho-vascular anatomy in pulmonary VATS/RATS. Assessing clinical feasibility of these approaches is crucial, particularly concerning registration accuracy and potential impact on surgical outcomes.

14.
Int J Mol Sci ; 25(11)2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38892001

RESUMEN

The deformability of red blood cells (RBCs), expressing their ability to change their shape as a function of flow-induced shear stress, allows them to optimize oxygen delivery to the tissues and minimize their resistance to flow, especially in microcirculation. During physiological aging and blood storage, or under external stimulations, RBCs undergo metabolic and structural alterations, one of which is hemoglobin (Hb) redistribution between the cytosol and the membrane. Consequently, part of the Hb may attach to the cell membrane, and although this process is reversible, the increase in membrane-bound Hb (MBHb) can affect the cell's mechanical properties and deformability in particular. In the present study, we examined the correlation between the MBHb levels, determined by mass spectroscopy, and the cell deformability, determined by image analysis. Six hemoglobin subunits were found attached to the RBC membranes. The cell deformability was negatively correlated with the level of four subunits, with a highly significant inter-correlation between them. These data suggest that the decrease in RBC deformability results from Hb redistribution between the cytosol and the cell membrane and the respective Hb interaction with the cell membrane.


Asunto(s)
Deformación Eritrocítica , Membrana Eritrocítica , Hemoglobinas , Humanos , Membrana Eritrocítica/metabolismo , Hemoglobinas/metabolismo , Eritrocitos/metabolismo , Unión Proteica
15.
Microvasc Res ; 146: 104473, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36587651

RESUMEN

BACKGROUND: Multiple myeloma is a complex pathology which represents about 10 % of all hematological neoplasms. It can often present changes in the hemorheological profile and, in relation to this last topic, our aim is to evaluate the hemorheological profile in a group of multiple myeloma patients, with reference to erythrocyte deformability. METHODS: We have examined the profile of the erythrocyte deformability in multiple myeloma enrolling 29 patients; this profile, expressed as elongation index at several shear stress, has been obtained using the diffractometric method. RESULTS: By comparing normal controls and MM patients, a significant decrease in erythrocyte deformability, especially at low shear stresses, but we did not observe any significant differences about this profile subdividing the whole group of MM patients according to the degree of bone marrow plasma cell infiltration, to the red blood cell distribution width and to the serum values of LDH. CONCLUSIONS: In this paper we have taken in consideration all the hypothesis for a possible explanation of the behaviour of this a reduced erythrocyte deformability in multiple myeloma. Erythrocyte deformability interferes with the physiological release of oxygen to tissues, with several clinical implications.


Asunto(s)
Deformación Eritrocítica , Mieloma Múltiple , Humanos , Mieloma Múltiple/diagnóstico , Viscosidad Sanguínea , Rayos Láser , Estrés Mecánico
16.
Microvasc Res ; 148: 104534, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37030528

RESUMEN

INTRODUCTION: Red blood cells (RBC) are one of the key elements of the microcirculation. Their ability to pass through capillaries and to deliver oxygen to cells is due to their large degree of deformability linked to the characteristics of the RBC membrane. Alterations in RBC deformability as a result of membrane damage, linked in part to increased synthesis of reactive oxygen species (ROS), can be observed in several diseases, such as sepsis, and may contribute to the altered microcirculation observed in these pathologies. Hyperbaric oxygen therapy (HBOT), with inhalation of 100 % oxygen, has been proposed in several acute or chronic pathologies, including carbon monoxide poisoning. OBJECTIVE: We investigated the effects of HBOT on oxidative stress from ROS produced by myeloperoxidase (MPO) and on RBC deformability in patients with acute or chronic inflammation (n = 10), in patients with acute carbon monoxide poisoning (n = 10), and in healthy volunteers (n = 10). METHODS: RBC deformability was evaluated before and after HBOT in the various populations using the ektacytometry technique (Laser-assisted Optical Rotational Red Cell Analyzer - LORRCA). Deformability was determined by the elongation index (EI) in relation to the shear stress (SS) over a range of 0.3 to 50 Pa. Oxidative stress was estimated through changes in proteins (chlorotyrosine and homocitrulline) induced by MPO activity measured by liquid chromatography-tandem mass spectrometry analysis. RESULTS: Before HBOT, EI was significantly lower in patients with acute or chronic inflammation than in healthy volunteers and patients with acute carbon monoxide poisoning for the majority of SS values studied. After one session of HBOT, the EI was significantly higher than before HBOT for SS values of 1.93 Pa or higher in patients with acute or chronic inflammation. This effect remains constant after 10 sessions. There were no differences before and after HBOT in protein or amino acid oxidation due to ROS generation mediated by MPO in the three populations. CONCLUSIONS: Our results confirm altered RBC deformability in patients with acute and chronic conditions associated with an underlying inflammatory process. HBOT improves deformability only after one session and therefore may improve microcirculation in this population. According to our results, this improvement does not seem mediated by the ROS pathway via MPO. These results need to be confirmed in a larger population.


Asunto(s)
Intoxicación por Monóxido de Carbono , Oxigenoterapia Hiperbárica , Humanos , Oxigenoterapia Hiperbárica/métodos , Intoxicación por Monóxido de Carbono/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Deformación Eritrocítica , Eritrocitos/metabolismo , Oxígeno/metabolismo , Inflamación/metabolismo
17.
Microvasc Res ; 148: 104549, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37192687

RESUMEN

Obstructive sleep apnoea (OSA) is a prevalent disorder that causes repetitive, temporary collapses of the upper airways during sleep, resulting in intermittent hypoxaemia and sleep fragmentation. Given those with OSA also exhibit decreased blood fluidity, this clinical population is at heightened risk for cardiovascular disease (CVD) development. Continuous positive airway pressure (CPAP) remains a primary therapy in OSA, which improves sleep quality and limits sleep fragmentation. While CPAP effectively ameliorates nocturnal hypoxic events and associated arousals, it remains unclear whether CVD risk factors are positively impacted. The aim of the present study was thus to assess the effects of an acute CPAP therapy on sleep quality and the physical properties of blood that determine blood fluidity. Sixteen participants with suspected OSA were recruited into the current study. Participants attended the sleep laboratory for two visits: an initial diagnostic visit that included confirmation of OSA severity and comprehensive assessments of blood parameters, followed by a subsequent visit where participants were administered an individualised, acute CPAP therapy session and had their blood assessments repeated. Holistic appraisal of blood rheological properties included assessment of blood and plasma viscosity, red blood cell (RBC) aggregation, deformability, and osmotic gradient ektacytometry. Acute CPAP treatment significantly improved sleep quality parameters, which were associated with decreased nocturnal arousals and improved blood oxygen saturation. Whole blood viscosity was significantly decreased following acute CPAP treatment, which might be explained by the improved RBC aggregation during this visit. Although an acute increase in plasma viscosity was observed, it appears that the alterations in RBC properties that mediate cell-cell aggregation, and thus blood viscosity, overcame the increased plasma viscosity. While deformability of RBC was unaltered, CPAP therapy had mild effects on the osmotic tolerance of RBC. Collectively, novel observations demonstrate that a single CPAP treatment session acutely improved sleep quality, which was accompanied by improved rheological properties.


Asunto(s)
Presión de las Vías Aéreas Positiva Contínua , Apnea Obstructiva del Sueño , Apnea Obstructiva del Sueño/patología , Apnea Obstructiva del Sueño/terapia , Humanos , Calidad del Sueño , Masculino , Femenino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Hemorreología
18.
Rev Cardiovasc Med ; 24(7): 196, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39077025

RESUMEN

Background: This study investigated the effects of 12-week resistance training on body composition, blood pressure, blood lipid levels, muscle cross-sectional area (CSA), isokinetic muscle function, and hemorheological properties in middle-aged obese women. Methods: Twenty-eight obese women with a mean age of 50.79 ± 5.80 years were randomly assigned to the control (CON, n = 13) or experimental (EXP, n = 15) group. The EXP group underwent a resistance training program composed of warm-up, main resistance exercise (deadlift, barbell squat, seated leg extension, and lying leg curl, bench press, preacher bench biceps curl, barbell rowing, and dumbbell shoulder press), and cool-down. The resistance exercise consisted of three sets of 8-10 repetitions (reps) performed with 70-80% of 1-rep maximum, and reps and sets were increased every 3 weeks. The training frequency was 80 min, 3 days per week for 12 weeks. The CON group maintained their daily lifestyle without training. All participants underwent measurements of body composition (weight, body mass index, lean body mass, fat mass, and % body fat), blood pressure (systolic blood pressure, diastolic blood pressure, mean arterial pressure, and pulse pressure), blood lipid levels (triglycerides, total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol), CSA of the muscles (quadriceps, hamstring, and total thigh muscle), isokinetic muscle function (peak torque [PT], relative PT, mean power, and total work [TW]), and hemorheological properties (erythrocyte deformability and aggregation) before and after 12 weeks of training. Results: The EXP group showed a significant improved muscle function, including PT (p < 0.001), relative PT (p < 0.001) in extension 60°/s, TW (p < 0.001) in extension 180°/s, and TW (p = 0.018) in flexion 180°/s. Regarding hemorheological properties, the EXP group showed significant improvement in erythrocyte aggregation (p < 0.001) and deformability (p < 0.001). Conclusions: The present study verified that our resistance training program resulted in greater muscle function, decreased fat mass, and improved hemorheological properties. Clinical Trial Registration: This study was registered with cris.nih.go.kr (No. KCT0007412).

19.
Nano Lett ; 22(22): 9054-9061, 2022 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-36321634

RESUMEN

In high-performance flexible and stretchable electronic devices, conventional inorganic semiconductors made of rigid and brittle materials typically need to be configured into geometrically deformable formats and integrated with elastomeric substrates, which leads to challenges in scaling down device dimensions and complexities in device fabrication and integration. Here we report the extraordinary mechanical properties of the newly discovered inorganic double helical semiconductor tin indium phosphate. This spiral-shape double helical crystal shows the lowest Young's modulus (13.6 GPa) among all known stable inorganic materials. The large elastic (>27%) and plastic (>60%) bending strains are also observed and attributed to the easy slippage between neighboring double helices that are coupled through van der Waals interactions, leading to the high flexibility and deformability among known semiconducting materials. The results advance the fundamental understanding of the unique polymer-like mechanical properties and lay the foundation for their potential applications in flexible electronics and nanomechanics disciplines.


Asunto(s)
Polímeros , Semiconductores , Polímeros/química , Electrónica , Módulo de Elasticidad , Elasticidad
20.
Nano Lett ; 22(7): 2923-2933, 2022 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-35333539

RESUMEN

Droplet manipulation is crucial for diverse applications ranging from bioassay to medical diagnosis. Current magnetic-field-driven manipulation strategies are mainly based on fixed or partially tunable structures, which limits their flexibility and versatility. Here, a reconfigurable magnetic liquid metal robot (MLMR) is proposed to address these challenges. Diverse droplet manipulation behaviors including steady transport, oscillatory transport, and release can be achieved by the MLMR, and their underlying physical mechanisms are revealed. Moreover, benefiting from the magnetic-field-induced active deformability and temperature-induced phase transition characteristics, its droplet-loading capacity and shape-locking/unlocking switching can be flexibly adjusted. Because of the fluidity-based adaptive deformability, MLMR can manipulate droplets in challenging confined environments. Significantly, MLMR can accomplish cooperative manipulation of multiple droplets efficiently through on-demand self-splitting and merging. The high-performance droplet manipulation using the reconfigurable and multifunctional MLMR unfolds new potential in microfluidics, biochemistry, and other interdisciplinary fields.


Asunto(s)
Robótica , Campos Magnéticos , Microfluídica
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