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1.
Proc Natl Acad Sci U S A ; 121(16): e2317202121, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38602913

RESUMEN

The distortion by gravity of a quasi-static bubble attached on an upward facing surface in a quiescent liquid is investigated. The contact angle evolution during the growth of such a bubble is studied, and the consequences on the motion of the contact line between the solid and the interface are discussed. From the initial case of a bubble attached to the rim of a nucleation site, the contact line can move inside the cavity for a highly wetting fluid, causing premature departure. For a higher wettability, the contact can either remain attached to the rim of the cavity or spread out of the cavity, depending on the cavity size and geometry. For the latter case, the bubble growth is investigated taking into account a contact angle hysteresis. Finally, a comprehensive map detailing various geometrical characteristics of bubbles is presented, ranging over several orders of magnitude of Bond numbers and normalized volumes. The map aims at being used as a tool for investigating bubble growth in a similar situation.

2.
Proc Natl Acad Sci U S A ; 120(15): e2219693120, 2023 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-37023134

RESUMEN

Corticostriatal activity is an appealing target for nonpharmacological treatments of brain disorders. In humans, corticostriatal activity may be modulated with noninvasive brain stimulation (NIBS). However, a NIBS protocol with a sound neuroimaging measure demonstrating a change in corticostriatal activity is currently lacking. Here, we combine transcranial static magnetic field stimulation (tSMS) with resting-state functional MRI (fMRI). We first present and validate the ISAAC analysis, a well-principled framework that disambiguates functional connectivity between regions from local activity within regions. All measures of the framework suggested that the region along the medial cortex displaying greater functional connectivity with the striatum is the supplementary motor area (SMA), where we applied tSMS. We then use a data-driven version of the framework to show that tSMS of the SMA modulates the local activity in the SMA proper, in the adjacent sensorimotor cortex, and in the motor striatum. We finally use a model-driven version of the framework to clarify that the tSMS-induced modulation of striatal activity can be primarily explained by a change in the shared activity between the modulated motor cortical areas and the motor striatum. These results suggest that corticostriatal activity can be targeted, monitored, and modulated noninvasively in humans.


Asunto(s)
Corteza Motora , Corteza Sensoriomotora , Humanos , Cuerpo Estriado/diagnóstico por imagen , Neostriado , Corteza Motora/diagnóstico por imagen , Corteza Motora/fisiología , Estimulación Magnética Transcraneal/métodos , Imagen por Resonancia Magnética
3.
J Neurosci ; 44(9)2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38302440

RESUMEN

Magnetic fields are being used for detailed anatomical and functional examination of the human brain. In addition, evidence for their efficacy in treatment of brain dysfunctions is accumulating. Transcranial static magnetic field stimulation (tSMS) is a recently developed technique for noninvasively modifying brain functions. In tSMS, a strong and small magnet when placed over the skull can temporarily suppress brain functions. Its modulatory effects persist beyond the time of stimulation. However, the neurophysiological mechanisms underlying tSMS-induced plasticity remain unclear. Here, using acute motor cortical slice preparation obtained from male C57BL/6N mice, we show that tSMS alters the intrinsic electrical properties of neurons by altering the activity of chloride (Cl-) channels in neurons. Exposure of mouse pyramidal neurons to a static magnetic field (SMF) at a strength similar to human tSMS temporarily decreased their excitability and induced transient neuronal swelling. The effects of SMF were blocked by DIDS and GlyH-101, but not by NPPB, consistent with the pharmacological profile of SLC26A11, a transporter protein with Cl- channel activity. Whole-cell voltage-clamp recordings of the GlyH-101-sensitive Cl- current component showed significant enhancement of the component at both subthreshold and depolarized membrane potentials after SMF application, resulting in shunting inhibition and reduced repetitive action potential (AP) firing at the respective potentials. Thus, this study provides the first neurophysiological evidence for the inhibitory effect of tSMS on neuronal activity and advances our mechanistic understanding of noninvasive human neuromodulation.


Asunto(s)
Cloruros , Glicina/análogos & derivados , Hidrazinas , Campos Magnéticos , Masculino , Humanos , Animales , Ratones , Ratones Endogámicos C57BL , Estimulación Magnética Transcraneal/métodos
4.
EMBO J ; 40(1): e105415, 2021 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-33185289

RESUMEN

Membrane transporters mediate cellular uptake of nutrients, signaling molecules, and drugs. Their overall mechanisms are often well understood, but the structural features setting their rates are mostly unknown. Earlier single-molecule fluorescence imaging of the archaeal model glutamate transporter homologue GltPh from Pyrococcus horikoshii suggested that the slow conformational transition from the outward- to the inward-facing state, when the bound substrate is translocated from the extracellular to the cytoplasmic side of the membrane, is rate limiting to transport. Here, we provide insight into the structure of the high-energy transition state of GltPh that limits the rate of the substrate translocation process. Using bioinformatics, we identified GltPh gain-of-function mutations in the flexible helical hairpin domain HP2 and applied linear free energy relationship analysis to infer that the transition state structurally resembles the inward-facing conformation. Based on these analyses, we propose an approach to search for allosteric modulators for transporters.


Asunto(s)
Sistema de Transporte de Aminoácidos X-AG/metabolismo , Proteínas Arqueales/metabolismo , Transporte Biológico/fisiología , Sistema de Transporte de Aminoácidos X-AG/genética , Archaea/genética , Archaea/metabolismo , Proteínas Arqueales/genética , Transporte Biológico/genética , Biología Computacional/métodos , Mutación con Ganancia de Función/genética , Modelos Moleculares , Pyrococcus horikoshii/genética , Pyrococcus horikoshii/metabolismo , Especificidad por Sustrato/genética
5.
Cereb Cortex ; 34(5)2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38741271

RESUMEN

This study investigates abnormalities in cerebellar-cerebral static and dynamic functional connectivity among patients with acute pontine infarction, examining the relationship between these connectivity changes and behavioral dysfunction. Resting-state functional magnetic resonance imaging was utilized to collect data from 45 patients within seven days post-pontine infarction and 34 normal controls. Seed-based static and dynamic functional connectivity analyses identified divergences in cerebellar-cerebral connectivity features between pontine infarction patients and normal controls. Correlations between abnormal functional connectivity features and behavioral scores were explored. Compared to normal controls, left pontine infarction patients exhibited significantly increased static functional connectivity within the executive, affective-limbic, and motor networks. Conversely, right pontine infarction patients demonstrated decreased static functional connectivity in the executive, affective-limbic, and default mode networks, alongside an increase in the executive and motor networks. Decreased temporal variability of dynamic functional connectivity was observed in the executive and default mode networks among left pontine infarction patients. Furthermore, abnormalities in static and dynamic functional connectivity within the executive network correlated with motor and working memory performance in patients. These findings suggest that alterations in cerebellar-cerebral static and dynamic functional connectivity could underpin the behavioral dysfunctions observed in acute pontine infarction patients.


Asunto(s)
Infartos del Tronco Encefálico , Cerebelo , Imagen por Resonancia Magnética , Vías Nerviosas , Puente , Humanos , Masculino , Femenino , Persona de Mediana Edad , Cerebelo/fisiopatología , Cerebelo/diagnóstico por imagen , Vías Nerviosas/fisiopatología , Vías Nerviosas/diagnóstico por imagen , Puente/diagnóstico por imagen , Puente/fisiopatología , Infartos del Tronco Encefálico/fisiopatología , Infartos del Tronco Encefálico/diagnóstico por imagen , Anciano , Adulto , Corteza Cerebral/fisiopatología , Corteza Cerebral/diagnóstico por imagen , Red Nerviosa/fisiopatología , Red Nerviosa/diagnóstico por imagen
6.
Cereb Cortex ; 34(1)2024 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-38061698

RESUMEN

Cerebral small vessel disease is common in most individuals aged 60 years or older, and it is associated with cognitive dysfunction, depression, anxiety disorder, and mobility problems. Currently, many cerebral small vessel disease patients have both cognitive impairment and depressive symptoms, but the relationship between the 2 is unclear. The present research combined static and dynamic functional network connectivity methods to explore the patterns of functional networks in cerebral small vessel disease individuals with cognitive impairment and depression (cerebral small vessel disease-mild cognitive impairment with depression) and their relationship. We found specific functional network patterns in the cerebral small vessel disease-mild cognitive impairment with depression individuals (P < 0.05). The cerebral small vessel disease individuals with depression exhibited unstable dynamic functional network connectivity states (transitions likelihood: P = 0.040). In addition, we found that the connections within the lateral visual network between the sensorimotor network and ventral attention network could mediate white matter hyperintensity-related cognitive impairment (indirect effect: 0.064; 95% CI: 0.003, 0.170) and depression (indirect effect: -0.415; 95% CI: -1.080, -0.011). Cognitive function can negatively regulate white matter hyperintensity-related depression. These findings elucidate the association between cognitive impairment and depression and provide new insights into the underlying mechanism of cerebral small vessel disease-related cognitive dysfunction and depression.


Asunto(s)
Enfermedades de los Pequeños Vasos Cerebrales , Disfunción Cognitiva , Sustancia Blanca , Humanos , Encéfalo/diagnóstico por imagen , Depresión/diagnóstico por imagen , Imagen por Resonancia Magnética , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/etiología , Enfermedades de los Pequeños Vasos Cerebrales/complicaciones , Enfermedades de los Pequeños Vasos Cerebrales/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen
7.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-35058364

RESUMEN

While there have been recent improvements in reducing bycatch in many fisheries, bycatch remains a threat for numerous species around the globe. Static spatial and temporal closures are used in many places as a tool to reduce bycatch. However, their effectiveness in achieving this goal is uncertain, particularly for highly mobile species. We evaluated evidence for the effects of temporal, static, and dynamic area closures on the bycatch and target catch of 15 fisheries around the world. Assuming perfect knowledge of where the catch and bycatch occurs and a closure of 30% of the fishing area, we found that dynamic area closures could reduce bycatch by an average of 57% without sacrificing catch of target species, compared to 16% reductions in bycatch achievable by static closures. The degree of bycatch reduction achievable for a certain quantity of target catch was related to the correlation in space and time between target and bycatch species. If the correlation was high, it was harder to find an area to reduce bycatch without sacrificing catch of target species. If the goal of spatial closures is to reduce bycatch, our results suggest that dynamic management provides substantially better outcomes than classic static marine area closures. The use of dynamic ocean management might be difficult to implement and enforce in many regions. Nevertheless, dynamic approaches will be increasingly valuable as climate change drives species and fisheries into new habitats or extended ranges, altering species-fishery interactions and underscoring the need for more responsive and flexible regulatory mechanisms.


Asunto(s)
Explotaciones Pesqueras , Conservación de los Recursos Naturales , Ecosistema , Oceanografía
8.
J Neurosci ; 43(4): 621-634, 2023 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-36639892

RESUMEN

Humans can label and categorize objects in a visual scene with high accuracy and speed, a capacity well characterized with studies using static images. However, motion is another cue that could be used by the visual system to classify objects. To determine how motion-defined object category information is processed by the brain in the absence of luminance-defined form information, we created a novel stimulus set of "object kinematograms" to isolate motion-defined signals from other sources of visual information. Object kinematograms were generated by extracting motion information from videos of 6 object categories and applying the motion to limited-lifetime random dot patterns. Using functional magnetic resonance imaging (fMRI) (n = 15, 40% women), we investigated whether category information from the object kinematograms could be decoded within the occipitotemporal and parietal cortex and evaluated whether the information overlapped with category responses to static images from the original videos. We decoded object category for both stimulus formats in all higher-order regions of interest (ROIs). More posterior occipitotemporal and ventral regions showed higher accuracy in the static condition, while more anterior occipitotemporal and dorsal regions showed higher accuracy in the dynamic condition. Further, decoding across the two stimulus formats was possible in all regions. These results demonstrate that motion cues can elicit widespread and robust category responses on par with those elicited by static luminance cues, even in ventral regions of visual cortex that have traditionally been associated with primarily image-defined form processing.SIGNIFICANCE STATEMENT Much research on visual object recognition has focused on recognizing objects in static images. However, motion is a rich source of information that humans might also use to categorize objects. Here, we present the first study to compare neural representations of several animate and inanimate objects when category information is presented in two formats: static cues or isolated dynamic motion cues. Our study shows that, while higher-order brain regions differentially process object categories depending on format, they also contain robust, abstract category representations that generalize across format. These results expand our previous understanding of motion-derived animate and inanimate object category processing and provide useful tools for future research on object category processing driven by multiple sources of visual information.


Asunto(s)
Reconocimiento Visual de Modelos , Corteza Visual , Humanos , Femenino , Masculino , Reconocimiento Visual de Modelos/fisiología , Percepción Visual/fisiología , Encéfalo/fisiología , Corteza Visual/fisiología , Imagen por Resonancia Magnética , Mapeo Encefálico , Estimulación Luminosa
9.
BMC Genomics ; 25(1): 423, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38684946

RESUMEN

BACKGROUND: Single-cell clustering has played an important role in exploring the molecular mechanisms about cell differentiation and human diseases. Due to highly-stochastic transcriptomics data, accurate detection of cell types is still challenged, especially for RNA-sequencing data from human beings. In this case, deep neural networks have been increasingly employed to mine cell type specific patterns and have outperformed statistic approaches in cell clustering. RESULTS: Using cross-correlation to capture gene-gene interactions, this study proposes the scCompressSA method to integrate topological patterns from scRNA-seq data, with support of self-attention (SA) based coefficient compression (CC) block. This SA-based CC block is able to extract and employ static gene-gene interactions from scRNA-seq data. This proposed scCompressSA method has enhanced clustering accuracy in multiple benchmark scRNA-seq datasets by integrating topological and temporal features. CONCLUSION: Static gene-gene interactions have been extracted as temporal features to boost clustering performance in single-cell clustering For the scCompressSA method, dual-channel SA based CC block is able to integrate topological features and has exhibited extraordinary detection accuracy compared with previous clustering approaches that only employ temporal patterns.


Asunto(s)
Análisis de la Célula Individual , Análisis de la Célula Individual/métodos , Análisis por Conglomerados , Humanos , Epistasis Genética , Análisis de Secuencia de ARN/métodos , Redes Reguladoras de Genes , Biología Computacional/métodos , Perfilación de la Expresión Génica/métodos , Algoritmos , Aprendizaje Profundo , Redes Neurales de la Computación
10.
Neuroimage ; 292: 120599, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38608799

RESUMEN

This study aimed to investigate altered static and dynamic functional network connectivity (FNC) and its correlation with clinical symptoms in patients with knee osteoarthritis (KOA). One hundred and fifty-nine patients with KOA and 73 age- and gender-matched healthy subjects (HS) underwent resting-state functional magnetic resonance imaging (rs-fMRI) and clinical evaluations. Group independent component analysis (GICA) was applied, and seven resting-state networks were identified. Patients with KOA had decreased static FNC within the default mode network (DM), visual network (VS), and cerebellar network (CB) and increased static FNC between the subcortical network (SC) and VS (p < 0.05, FDR corrected). Four reoccurring FNC states were identified using k-means clustering analysis. Although abnormalities in dynamic FNCs of KOA patients have been found using the common window size (22 TR, 44 s), but the results of the clustering analysis were inconsistent when using different window sizes, suggesting dynamic FNCs might be an unstable method to compare brain function between KOA patients and HS. These recent findings illustrate that patients with KOA have a wide range of abnormalities in the static and dynamic FNCs, which provided a reference for the identification of potential central nervous therapeutic targets for KOA treatment and might shed light on the other musculoskeletal pain neuroimaging studies.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Red Nerviosa , Osteoartritis de la Rodilla , Humanos , Imagen por Resonancia Magnética/métodos , Femenino , Masculino , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/fisiopatología , Persona de Mediana Edad , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiopatología , Anciano , Encéfalo/diagnóstico por imagen , Encéfalo/fisiopatología , Adulto , Conectoma/métodos , Descanso , Mapeo Encefálico/métodos
11.
Antimicrob Agents Chemother ; : e0044824, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38742904

RESUMEN

Phage-antibiotic combination treatment is a novel noteworthy drug delivery method in anti-infection. In the current study, we have isolated a new phage, pB23, against carbapenem-resistant Acinetobacter baumannii 2023. Synergistic antibacterial effect between phage pB23 and meropenem combination could be more stable, using moderate doses of phage (multiplicity of infection ranging from 0.1 to 1,000) based on results of in vitro antibacterial activity. Phage pB23 and meropenem combination could effectively clear mature biofilms and prevent biofilm formation of carbapenem-resistant Acinetobacter baumannii in vitro. Phage pB23 and meropenem combination also has good synergistic antibacterial effects against carbapenem-resistant Acinetobacter baumannii in different growth phases under static culture conditions. The pig skin explant model shows that phage pB23 and meropenem combination has a synergistic effect to remove bacteria from wounds ex vivo. Phage pB23 and meropenem combination also exhibited a synergistic antibacterial effect in vivo using a zebrafish infection mode. The potential promotion of phage proliferation by meropenem and the sensitivity recovery of phage-resistant bacteria to meropenem might elucidate the mechanism of the synergistic antimicrobial activity. In summary, our study illustrates that phage pB23 and meropenem combination could produce synergistic antibacterial effects against carbapenem-resistant Acinetobacter baumannii under static growth conditions. This study also demonstrates that phage-antibiotic combination will become an effective strategy to enhance antibacterial activity of individual drug and provide a new idea of the drug development for the treatment of infections due to carbapenem-resistant Acinetobacter baumannii and other multidrug-resistant bacteria.

12.
Am J Physiol Heart Circ Physiol ; 326(3): H548-H562, 2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-38180451

RESUMEN

This study investigated cardiac stress and mitochondrial oxidative phosphorylation (OxPhos) in human donation after circulatory death (DCD) hearts regarding warm ischemic time (WIT) and subsequent cold storage and compared them with that of human brain death donor (DBD) hearts. A total of 24 human hearts were procured for the research study-6 in the DBD group and 18 in the DCD group. DCD group was divided into three groups (n = 6) based on different WITs (20, 40, and 60 min). All hearts received del Nido cardioplegia before being placed in normal saline cold storage for 6 h. Left ventricular biopsies were performed at hours 0, 2, 4, and 6. Cardiac stress [nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunits: 47-kDa protein of phagocyte oxidase (p47phox), 91-kDa glycoprotein of phagocyte oxidase (gp91phox)] and mitochondrial oxidative phosphorylation [OxPhos, complex I (NADH dehydrogenase) subunit of ETC (CI)-complex V (ATP synthase) subunit of ETC (CV)] proteins were measured in cardiac tissue and mitochondria respectively. Modulation of cardiac stress and mitochondrial dysfunction were observed in both DCD and DBD hearts. However, DCD hearts suffered more cardiac stress (overexpressed NADPH oxidase subunits) and diminished mitochondrial OxPhos than DBD hearts. The severity of cardiac stress and impaired oxidative phosphorylation in DCD hearts correlated with the longer WIT and subsequent cold storage time. More drastic changes were evident in DCD hearts with a WIT of 60 min or more. Activation of NADPH oxidase via overproduction of p47phox and gp91phox proteins in cardiac tissue may be responsible for cardiac stress leading to diminished mitochondrial oxidative phosphorylation. These protein changes can be used as biomarkers for myocardium damage and might help assess DCD and DBD heart transplant suitability.NEW & NOTEWORTHY First human DCD heart research studied cardiac stress and mitochondrial dysfunction concerning WIT and the efficacy of del Nido cardioplegia as an organ procurement solution and subsequent cold storage. Mild to moderate cardiac stress and mitochondrial dysfunction were noticed in DCD hearts with WIT 20 and 40 min and cold storage for 4 and 2 h, respectively. These changes can serve as biomarkers, allowing interventions to preserve mitochondria and extend WIT in DCD hearts.


Asunto(s)
Trasplante de Corazón , Enfermedades Mitocondriales , Humanos , Muerte Encefálica , Fosforilación Oxidativa , Donantes de Tejidos , NADPH Oxidasas , Biomarcadores , Oxidorreductasas , Muerte , Estudios Retrospectivos
13.
Small ; : e2402221, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39161204

RESUMEN

Hydrogel droplets with inner compartments are valuable in various fields, including tissue engineering. A droplet-based biofabrication method is presented for the chaos-assisted production of architected spheres (CAPAS) for the rapid generation of multilayered hydrogel spheres (ranging from 0.6 to 3.5 mm in diameter) at high-throughput rates (up to 2000 spheres per min). This method is based on the use of chaotic advection generated by a Kenics static mixer (KSM) nozzle. The configuration of the KSM (i.e., the number of mixing elements) determines the number of compartments within the sphere. Sphere size is adjusted by flow rate, printhead outlet diameter, polymer concentration (sodium alginate or gelatin-methacryloyl (GelMA)), and crosslinking bath composition. This versatile system operates in dripping and jetting modes, preserving multilayered architecture in both modes. Proof-of-concept experiments with breast cancer (MDA-MB-231), human dermal fibroblast (HDF), and murine myoblast (C2C12) lines show over 80% cell viability immediately post-fabrication, maintained over extended culture (14 or 30 days). CAPAS is used to create a breast cancer model with cancer-tissue-like and healthy-tissue-like micro-niches to test paclitaxel doses. It is envisioned that CAPAS will enable high-throughput fabrication of hydrogel spheres for tissue engineering, chemical engineering, and material sciences applications.

14.
Small ; 20(11): e2303880, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37661596

RESUMEN

Domain walls separating differently oriented polarization regions of ferroelectric materials are known to greatly impact nanoscale materials and device functionalities. Though the understanding of size effects in ferroelectric nanostructures has progressed, the effect of thickness downsizing on domain wall scaling behavior has remained unexplored. Using piezoresponse force microscopy, epitaxial BaTiO3 film thickness size (2-90 nm) effects on the critical scaling universality of the domain wall dynamical creep and static roughness exponents including dimensionality is demonstrated. Independently estimated static roughness exponents ranging between 0.34 and 0.28 and dynamical creep exponents transition from 0.54 to 0.22 elucidate the domain wall dimensionality transition from two- to quasi-one-dimension in the thickness range of 10-25 nm, which is later validated by evaluating effective dimensionality within the paradigm of random-bond universality. The observed interdimensional transition is further credenced to the compressive strain and long-range strain-dipolar interactions, as revealed by the structural analyses and additional measurements with modified substrate-induced strain. These results provide new insights into the understanding of size effects in nanoscale ferroelectricity, paving the way toward future nanodevices.

15.
J Transl Med ; 22(1): 221, 2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-38429788

RESUMEN

BACKGROUND: Cellular stress associated with static-cold storage (SCS) and warm reperfusion of donor lungs can contribute to ischemia-reperfusion (IR) injury during transplantation. Adding cytoprotective agents to the preservation solution may be conducive to reducing graft deterioration and improving post-transplant outcomes. METHODS: SCS and warm reperfusion were simulated in human lung epithelial cells (BEAS-2B) by exposing cells to low potassium dextran glucose solution at 4 °C for different periods and then switching back to serum-containing culture medium at 37 °C. Transcriptomic analysis was used to explore potential cytoprotective agents. Based on its results, cell viability, caspase activity, cell morphology, mitochondrial function, and inflammatory gene expression were examined under simulated IR conditions with or without thyroid hormones (THs). RESULTS: After 18 h SCS followed by 2 h warm reperfusion, genes related to inflammation and cell death were upregulated, and genes related to protein synthesis and metabolism were downregulated in BEAS-2B cells, which closely mirrored gene profiles found in thyroid glands of mice with congenital hypothyroidism. The addition of THs (T3 or T4) to the preservation solution increases cell viability, inhibits activation of caspase 3, 8 and 9, preserves cell morphology, enhances mitochondrial membrane potential, reduces mitochondrial superoxide production, and suppresses inflammatory gene expression. CONCLUSION: Adding THs to lung preservation solutions may protect lung cells during SCS by promoting mitochondrial function, reducing apoptosis, and inhibiting pro-inflammatory pathways. Further in vivo testing is warranted to determine the potential clinical application of adding THs as therapeutics in lung preservation solutions.


Asunto(s)
Preservación de Órganos , Daño por Reperfusión , Humanos , Ratones , Animales , Preservación de Órganos/métodos , Pulmón/metabolismo , Reperfusión , Células Epiteliales/metabolismo , Hormonas Tiroideas/farmacología , Hormonas Tiroideas/metabolismo
16.
Ophthalmology ; 131(6): 658-666, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38110124

RESUMEN

PURPOSE: The newly released Swedish Interactive Thresholding Algorithm (SITA)-Faster (SFR) has significantly shorter testing durations compared with older SITA algorithms, but its variability is uncertain. This study quantified and established threshold limits of test-retest variability across the 24-2 test grid using SFR. DESIGN: Cross-sectional study with prospective longitudinal arm. PARTICIPANTS: 1426 eyes of 787 patients with healthy, suspected glaucoma, or manifest glaucoma eyes from hospital- and university- eye clinics. METHODS: Two SFR tests per eye at a baseline visit and at two follow-up visits. MAIN OUTCOME MEASURES: Pointwise variability measured by test-retest difference in pointwise sensitivity between tests one and two, mean global variability (test-retest variance) measured by average of pointwise variability for each participant, global sensitivity, and reliability indices of each eye. RESULTS: Of the 1426 eyes, 540 eyes (37.9%) had a diagnosis of glaucoma, 753 eyes (52.8%) were suspected of having glaucoma, and the remaining 133 eyes (9.3%) were healthy. Of 74 152 pointwise sensitivities obtained, the mean test-retest difference was 2.17 ± 2.9 dB, whereas the mean test-retest variance for each participant was 2.17 ± 1.2 dB. Pointwise and global variability increased with worsening threshold sensitivity and (MD), respectively, and was greater for peripheral compared with central test locations. In the longitudinal cohort, no significant difference in mean test-retest variance was found across the 3 visits (mean variability, 2.10 dB vs. 2.16 dB vs. 2.16 dB at visits F0 vs. F1 vs. F2; P = 0.53, repeated-measures analysis of variance). Baseline MD (-0.19 dB; 95% CI, -0.22 to 0.16 dB; P < 0.0001) and abnormally high sensitivity on glaucoma hemifield test (1.14 dB; 95% CI, 0.78-1.51 dB; P < 0.0001) were significantly associated with increased variability. Finally, test-retest MD showed minimal change around the recommended 15% false-positive cutoff threshold. CONCLUSIONS: The variability of SFR increases with worsening threshold sensitivity, is stable over time, and is greater for peripheral compared with central test locations. Worse baseline MD and abnormally high sensitivity are significant predictors of increased variability. A cutoff of 15% in false-positive results may be inappropriate as a threshold for judging test reliability in SFR. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.


Asunto(s)
Algoritmos , Presión Intraocular , Hipertensión Ocular , Pruebas del Campo Visual , Campos Visuales , Humanos , Campos Visuales/fisiología , Masculino , Estudios Prospectivos , Femenino , Estudios Transversales , Pruebas del Campo Visual/métodos , Persona de Mediana Edad , Presión Intraocular/fisiología , Anciano , Reproducibilidad de los Resultados , Hipertensión Ocular/diagnóstico , Hipertensión Ocular/fisiopatología , Trastornos de la Visión/diagnóstico , Trastornos de la Visión/fisiopatología , Glaucoma/diagnóstico , Glaucoma/fisiopatología , Sensibilidad y Especificidad , Adulto , Glaucoma de Ángulo Abierto/diagnóstico , Glaucoma de Ángulo Abierto/fisiopatología , Umbral Sensorial/fisiología
17.
Respir Res ; 25(1): 209, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750527

RESUMEN

BACKGROUND: Limited research has investigated the relationship between small airway dysfunction (SAD) and static lung hyperinflation (SLH) in patients with post-acute sequelae of COVID-19 (PASC) especially dyspnea and fatigue. METHODS: 64 patients with PASC were enrolled between July 2020 and December 2022 in a prospective observational cohort. Pulmonary function tests, impulse oscillometry (IOS), and symptom questionnaires were performed two, five and eight months after acute infection. Multivariable logistic regression models were used to test the association between SLH and patient-reported outcomes. RESULTS: SLH prevalence was 53.1% (34/64), irrespective of COVID-19 severity. IOS parameters and circulating CD4/CD8 T-cell ratio were significantly correlated with residual volume to total lung capacity ratio (RV/TLC). Serum CD8 + T cell count was negatively correlated with forced expiratory volume in the first second (FEV1) and forced vital capacity (FVC) with statistical significance. Of the patients who had SLH at baseline, 57% continued to have persistent SLH after eight months of recovery, with these patients tending to be older and having dyspnea and fatigue. Post-COVID dyspnea was significantly associated with SLH and IOS parameters R5-R20, and AX with adjusted odds ratios 12.4, 12.8 and 7.6 respectively. SLH was also significantly associated with fatigue. CONCLUSION: SAD and a decreased serum CD4/CD8 ratio were associated with SLH in patients with PASC. SLH may persist after recovery from infection in a substantial proportion of patients. SAD and dysregulated T-cell immune response correlated with SLH may contribute to the development of dyspnea and fatigue in patients with PASC.


Asunto(s)
COVID-19 , Pulmón , Síndrome Post Agudo de COVID-19 , Pruebas de Función Respiratoria , Humanos , Masculino , Femenino , Persona de Mediana Edad , COVID-19/fisiopatología , COVID-19/complicaciones , COVID-19/epidemiología , COVID-19/diagnóstico , COVID-19/inmunología , Estudios Prospectivos , Pulmón/fisiopatología , Pruebas de Función Respiratoria/métodos , Anciano , Adulto , Recuperación de la Función , Factores de Tiempo , Disnea/fisiopatología , Disnea/epidemiología , Disnea/diagnóstico , Volumen Espiratorio Forzado/fisiología
18.
J Evol Biol ; 2024 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-39180283

RESUMEN

The evolution of sexual dimorphism is widely acknowledged as manifestation of sex-specific genetic architecture. Although empirical studies suggested that sexual dimorphism evolves as a joint consequence of constraints arising from the genetic architecture and sexually divergent selection, it remains unclear whether and how these established microevolutionary processes scale up to the macroevolutionary patterns of sexual dimorphism among taxa. Here, we studied how sexual selection and parental care drive sexual dimorphism in cichlid fishes from Lake Tanganyika. We found that male-male competition, female choice, and maternal mouthbrooding are associated with sexual dimorphism in body length, body color, and head length, respectively, despite strong allometric relationships between body length and head length. Within-species (static) allometry of head length on body length evolved as sex-specific responses to mouthbrooding where females evolved higher intercepts while males evolved steeper slopes. Thus, selection to increase mouth size in mouthbrooders may have broken down and reorganized the pattern of allometric constraints that are inherently strong and concordant between sexes. Furthermore, sex-specific responses to mouthbrooding left a remarkably clear signature on the macroevolutionary pattern, resulting in a decoupling of co-evolution in parameters of static allometries observed exclusively within maternal mouthbrooders. Our study provides multiple lines of evidence that are consistent with the idea that macroevolutionary patterns of sexual dimorphism in Lake Tanganyika cichlids result from sexually divergent selection. Our approach illustrates that an examination of within-population phenotypic variance in the phylogenetic comparative framework may facilitate nuanced understandings of how macroevolutionary patterns are generated by underlying microevolutionary processes.

19.
FASEB J ; 37(7): e22985, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37249350

RESUMEN

Osteoporosis is one of the chronic complications of type 1 diabetes with high risk of fracture. The prevention of diabetic osteoporosis is of particular importance. Static magnetic fields (SMFs) exhibit advantages on improvement of diabetic complications. The biological effects and mechanism of SMFs on bone health of type 1 diabetic mice and functions of bone cells under high glucose have not been clearly clarified. In animal experiment, six-week-old male C57BL/6J mice were induced to type 1 diabetes and exposed to SMF of 0.4-0.7 T for 4 h/day lasting for 6 weeks. Bone mass, biomechanical strength, microarchitecture and metabolism were determined by DXA, three-point bending assay, micro-CT, histochemical and biochemical methods. Exposure to SMF increased BMD and BMC of femur, improved biomechanical strength with higher ultimate stress, stiffness and elastic modulus, and ameliorated the impaired bone microarchitecture in type 1 diabetic mice by decreasing Tb.Pf, Ct.Po and increasing Ct.Th. SMF enhanced bone turnover by increasing the level of markers for bone formation (OCN and Collagen I) as well as bone resorption (CTSK and NFAT2). In cellular experiment, MC3T3-E1 cells or primary osteoblasts and RAW264.7 cells were cultured in 25 mM high glucose-stimulated diabetic marrow microenvironment under differentiation induction and exposed to SMF. SMF promoted osteogenesis with higher ALP level and mineralization deposition in osteoblasts, and it also enhanced osteoclastogenesis with higher TRAP activity and bone resorption in osteoclasts under high glucose condition. Further, SMF increased iron content with higher FTH1 expression and regulated the redox level through activating HO-1/Nrf2 in tibial tissues, and lowered hepatic iron accumulation by BMP6-mediated regulation of hepcidin and lipid peroxidation in mice with type 1 diabetes. Thus, SMF may act as a potential therapy for improving bone health in type 1 diabetes with regulation on iron homeostasis metabolism and redox status.


Asunto(s)
Resorción Ósea , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Osteoporosis , Ratones , Masculino , Animales , Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Experimental/terapia , Ratones Endogámicos C57BL , Osteoblastos/metabolismo , Osteogénesis , Hierro/metabolismo , Oxidación-Reducción , Campos Magnéticos , Glucosa
20.
Mol Pharm ; 21(3): 1414-1423, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38386020

RESUMEN

Protein self-interactions measured via second osmotic virial coefficients (B22) and dynamic light scattering interaction parameter values (kD) are often used as metrics for assessing the favorability of protein candidates and different formulations during monoclonal antibody (MAb) product development. Model predictions of B22 or kD typically do not account for glycans, though glycosylation can potentially impact experimental MAb self-interactions. To the best of our knowledge, the impact of MAb glycosylation on the experimentally measured B22 and kD values has not yet been reported. B22 and kD values of two fully deglycosylated MAbs and their native (i.e., fully glycosylated) counterparts were measured by light scattering over a range of pH and ionic strength conditions. Significant differences between B22 and kD of the native and deglycosylated forms were observed at a range of low to high ionic strengths used to modulate the effect of electrostatic contributions. Differences were most pronounced at low ionic strength, indicating that electrostatic interactions are a contributing factor. Though B22 and kD values were statistically equivalent at high ionic strengths where electrostatics were fully screened, we observed protein-dependent qualitative differences, which indicate that steric interactions may also play a role in the observed B22 and kD differences. A domain-level coarse-grained molecular model accounting for charge differences was considered to potentially provide additional insight but was not fully predictive of the behavior across all of the solution conditions investigated. This highlights that both the level of modeling and lack of inclusion of glycans may limit existing models in making quantitatively accurate predictions of self-interactions.


Asunto(s)
Anticuerpos Monoclonales , Polisacáridos , Anticuerpos Monoclonales/química , Glicosilación , Dispersión Dinámica de Luz , Modelos Moleculares , Concentración de Iones de Hidrógeno , Concentración Osmolar
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