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1.
Cyborg Bionic Syst ; 5: 0083, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38533379

RESUMO

This work presents a novel electromagnetic driving system that consists of eight optimized electromagnets arranged in an optimal configuration and employs a control framework based on an active disturbance rejection controller (ADRC) and virtual boundary. The optimal system configuration enhances the system's compatibility with other ophthalmic surgical instruments, while also improving its capacity to generate magnetic force in the vertical direction. Besides, the optimal electromagnet parameters provide a superior comprehensive performance on magnetic field generation capacity and thermal power. Hence, the presented design achieves a stronger capacity for sustained work. Furthermore, the ADRC controller effectively monitors and further compensates the total disturbance as well as gravity to enhance the system's robustness. Meanwhile, the implementation of virtual boundaries substantially enhances interactive security via collision avoidance. The magnetic and thermal performance tests have been performed on the electromagnet to verify the design optimization. The proposed electromagnet can generate a superior magnetic field of 2.071 mT at a distance of 65 mm with an applied current of 1 A. Moreover, it demonstrates minimal temperature elevation from room temperature (25 °C) to 46 °C through natural heat dissipation in 3 h, thereby effectively supporting prolonged magnetic manipulation of intraocular microsurgery. Furthermore, trajectory tracking experiments with disturbances have been performed in a liquid environment similar to the practical ophthalmic surgery scenarios, to verify the robustness and security of the presented control framework. The maximum root mean square (RMS) error of performance tests in different operation modes remains 35.8 µm, providing stable support for intraocular microsurgery.

2.
J Gen Intern Med ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38467918

RESUMO

BACKGROUND: Adults with type 1 or type 2 diabetes often face financial challenges and other unmet social needs to effective diabetes self-management. OBJECTIVE: Whether a digital intervention focused on addressing socioeconomic determinants of health improves diabetes clinical outcomes more than usual care. DESIGN: Randomized trial from 2019 to 2023. PARTICIPANTS: A total of 600 adults with diabetes, HbA1c ≥ 7.5%, and self-reported unmet social needs or financial burden from a health system and randomized to the intervention or standard care. INTERVENTION: CareAvenue is an automated, e-health intervention with eight videos that address unmet social needs contributing to poor outcomes. MEASURES: Primary outcome was HbA1c, measured at baseline, and 6 and 12 months after randomization. Secondary outcomes included systolic blood pressure and reported met social needs, cost-related non-adherence (CRN), and financial burden. We examined main effects and variation in effects across predefined subgroups. RESULTS: Seventy-eight percent of CareAvenue participants completed one or more modules of the website. At 12-month follow-up, there were no significant differences in HbA1c changes between CareAvenue and control group (p = 0.24). There were also no significant between-group differences in systolic blood pressure (p = 0.29), met social needs (p = 0.25), CRN (p = 0.18), and perceived financial burden (p = 0.31). In subgroup analyses, participants with household incomes 100-400% FPL (1.93 (SE = 0.76), p < 0.01), 201-400% FPL (1.30 (SE = 0.62), p < 0.04), and > 400% FPL (1.27 (SE = 0.64), p < 0.05) had significantly less A1c decreases compared to the control group. CONCLUSIONS: On average, CareAvenue participants did not achieve better A1c lowering, met needs, CRN, or perceived financial burden compared to control participants. CareAvenue participants with higher incomes achieved significantly less A1c reductions than control. Further research is needed on social needs interventions that consider tailored approaches to population subgroups. CLINICAL TRIALS REGISTRY: ClinicalTrials.gov ID NCT03950973, May 2019.

3.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 41(1): 98-104, 2024 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-38403609

RESUMO

Transcranial magnetic stimulation (TMS), a widely used neuroregulatory technique, has been proven to be effective in treating neurological and psychiatric disorders. The therapeutic effect is closely related to the intracranial electric field caused by TMS, thus accurate measurement of the intracranial electric field generated by TMS is of great significance. However, direct intracranial measurement in human brain faces various technical, safety, ethical and other limitations. Therefore, we have constructed a brain phantom that can simulate the electrical conductivity and anatomical structure of the real brain, in order to replace the clinical trial to achieve intracranial electric field measurement. We selected and prepared suitable conductive materials based on the electrical conductivity of various layers of the real brain tissue, and performed image segmentation, three-dimensional reconstruction and three-dimensional printing processes on each layer of tissue based on magnetic resonance images. The production of each layer of tissue in the brain phantom was completed, and each layer of tissue was combined to form a complete brain phantom. The induced electric field generated by the TMS coil applied to the brain phantom was measured to further verify the conductivity of the brain phantom. Our study provides an effective experimental tool for studying the distribution of intracranial electric fields caused by TMS.


Assuntos
Encéfalo , Estimulação Magnética Transcraniana , Humanos , Encéfalo/fisiologia , Estimulação Magnética Transcraniana/métodos , Cabeça , Mapeamento Encefálico/métodos , Condutividade Elétrica , Campos Eletromagnéticos
4.
Chemistry ; 30(18): e202303857, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38205617

RESUMO

The methods for the cross-coupling of aryl(trialkyl)silanes are long-standing challenges due to the extreme inertness of C-Si(R3) bond, though the reaction is environmentally friendly and highly regioselective to synthesize biaryls. Herein, we report a copper-catalyzed cross-coupling of aryl(trialkyl)silanes and aryl via a radical mechanism. The reaction proceeds efficiently with aryl sulfonium salts as limiting reagents, exhibits broad substrate scope, and provides an important synthetic strategy to acquire biaryls, exemplified by unsymmetrical fluorescence probes and late-stage functionalization of drugs. Of note, the experimental and theoretical mechanistic studies revealed a radical mechanism where the copper catalyst and CsF play critical roles on the radical generation and desilylation process.

5.
Neurology ; 102(2): e207960, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38165320

RESUMO

BACKGROUND AND OBJECTIVES: During acute hospitalizations, physicians often focus on the stroke patient and not family who may be traumatized by this sudden change to their loved one. We investigated long-term psychological distress among family surrogate decision makers for Mexican American (MA) and non-Hispanic White (NHW) severe stroke patients. Previous work in other diseases suggested worse psychological outcomes in MA than NHW caregivers. METHODS: This was a population-based, prospective cohort study in Nueces County, TX. Stroke patient participants and their surrogate decision makers were enrolled soon after any stroke between April, 2016, and October, 2020, if surrogates had made decisions about life-sustaining treatments. Surrogates completed validated measures of posttraumatic stress, National Stressful Events Survey for Posttraumatic Stress Disorder Short Scale; anxiety, Generalized Anxiety Disorder-7; and depression, Patient Health Questionnaire-8 at discharge, 3, 6, and 12 months. Ethnic differences were assessed with multilevel linear mixed models, sequentially adjusted for prespecified patient and surrogate demographic, socioeconomic, and clinical covariates. RESULTS: There were 301 family surrogates for 241 severe stroke patients. The mean follow-up was 315 days. High scores on measures of psychological distress ranged between 17% and 28% of surrogates. One or more high levels of the psychological outcomes were found in 17%-43% of surrogates; 2 or more were found in 12%-27%; and all 3 were found in 5%-16% of surrogates. All psychological outcomes were worse among MAs on unadjusted analyses. In fully adjusted models, posttraumatic stress remained worse among MAs (0.36, 95% CI 0.17-0.56); ethnic differences were attenuated and no longer significant in the final model for anxiety (0.59, 95% CI -0.55 to 1.74) and depression (0.97, 95% CI -0.25 to 2.19). The trajectory for depression did differ by ethnicity (interaction p = 0.03), with depression score improving more rapidly over time among NHWs than MAs. Advance care plans did not seem to confound any ethnic differences. DISCUSSION: Psychological distress is common among family surrogate decision makers in the year after stroke and may be worse among MAs. Efforts are needed to support family members of all ethnic groups after severe stroke.


Assuntos
Cuidadores , Angústia Psicológica , Acidente Vascular Cerebral , Humanos , Tomada de Decisões , Etnicidade , Americanos Mexicanos , Estudos Prospectivos , Acidente Vascular Cerebral/epidemiologia , Brancos , Cuidadores/psicologia
6.
Eur J Med Res ; 29(1): 50, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38217043

RESUMO

BACKGROUND: Stroke is the second leading cause of death worldwide, and observational studies have suggested a correlation between antioxidants and reduced stroke risk. However, it remains unclear whether causal relationships exist. METHODS: This study first performed a cross-sectional study of the association between the Composite Dietary Antioxidant Index (CDAI) and stroke using data from the National Health and Nutrition Examination Survey (NHANES) 2007-2018. Second, a two-sample univariable Mendelian Randomization (MR) was performed to analyze the causal effect of circulating levels of antioxidants on different subtypes of stroke. RESULTS: The cross-sectional study included a total of 24,892 participants representing more than 200 million US non-institutionalized residents, a multivariable logistic regression model revealed that the risk of stroke decreased by 3.4% for each unit increase in CDAI (P = 0.017), with a non-linear association found, indicating a reduction in stroke risk before an inflection point of 3.078. MR analysis revealed that genetically determined levels of retinol had a suggestive protective effect on subarachnoid hemorrhage (SAH) (OR = 0.348, P = 0.025), and genetically determined levels of selenium had a suggestive protective effect against SAH (OR = 0.826, P = 0.007). However, no causal relationship was found between antioxidants and ischemic stroke or intracranial hemorrhage risk. CONCLUSIONS: Evidence suggests that diet-derived antioxidants may reduce the risk of stroke, as indicated by the protective effects of retinol and selenium against SAH. However, more research is needed to fully understand how antioxidants prevent stroke.


Assuntos
Selênio , Acidente Vascular Cerebral , Humanos , Antioxidantes , Vitamina A , Inquéritos Nutricionais , Estudos Transversais , Análise da Randomização Mendeliana , Acidente Vascular Cerebral/genética
7.
Sci Rep ; 14(1): 904, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195914

RESUMO

CircRNAs play an important role in various physiological and pathological biological processes. Despite their widespread involvement, the function of circRNAs in intermittent hypoxia (IH) remain incompletely understood. This study aims to clarify the molecular mechanism of it in IH. Differentially expressed circRNAs were identified by transcriptome sequencing analysis in intermittent hypoxia (IH) model. GO and KEGG enrichment analys were performed on the identified differentially expressed circRNAs. The circular characteristics of hsa_circ_0081065 in human umbilical vein endothelial cells (HUVECs) were detected by RT-qPCR. The sublocalization of hsa_circ_0081065 was examined by FISH. The effect of hsa_circ_0081065 on endothelial to mesenchymal transition (EndMT) was estimated by detecting the expression of EndMT related markers. Various techniques, including RNA-pull down, RIP, EMSA, dual-luciferase reporter assay and immunofluorescence staining were used to investigate the relationship among hsa_circ_0081065, miR-665 and HIF-1α. A total of 13,304 circRNAs were identified in HUVECs treatment with IH, among which 73 were differentially expressed, including 24 upregulated circRNAs and 49 downregulated circRNAs. Notably, hsa_circ_0081065 demonstrated a significantly upregulation. Hsa_circ_0081065 exhibited the circular characteristics of circRNA and was predominantly localized in the cytoplasm. Knockdown of hsa_circ_0081065 inhibited EndMT. Mechanically, we demonstrated that hsa_circ_0081065 acts as a sponge for miR-665 to up-regulate HIF-1α and exacerbate HIF-1α nuclear translocation in HUVECs. We have demonstrated that hsa_circ_0081065 is significantly upregulated in HUVECs treated with IH. Our findings indicate that hsa_circ_0081065 exacerbates IH-induced EndMT through the regulation of the miR-665/HIF-1α signal axis and facilitating HIF-1α nuclear translocation. These results provide a theoretical basis for considering of EndMT as a potential therapeutic target for OSAHS intervention.


Assuntos
60483 , MicroRNAs , Humanos , RNA Circular/genética , Células Endoteliais da Veia Umbilical Humana , Hipóxia , MicroRNAs/genética
8.
Stroke ; 55(3): 678-686, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38214155

RESUMO

BACKGROUND: Patients with severe stroke often rely on surrogate decision-makers for life-sustaining treatment decisions. We investigated ethnic differences between Mexican Americans (MAs) and non-Hispanic White (NHW) individuals in surrogate reports of physician quality of communication and shared decision-making from the OASIS study (Outcomes Among Surrogate Decision Makers in Stroke) project. METHODS: Patients had ischemic stroke or intracerebral hemorrhage in Nueces County, TX. Surrogates self-identified as being involved in decisions about do-not-resuscitate orders, brain surgery, ventilator, feeding tube, or hospice/comfort care. Surrogate reports of physician quality of communication (scale score, range from 0 to 10) and shared decision-making (CollaboRATE scale score, binary score 1 versus 0) were compared by ethnicity with linear or logistic regression using generalized estimating equations, adjusted for prespecified demographics, clinical factors, and confounders. RESULTS: Between April 2016 and September 2020, 320 surrogates for 257 patients with stroke enrolled (MA, 158; NHW, 85; and other, 14). Overall quality of communication score was better among surrogates of MA patients than NHW individuals after adjustment for demographics, stroke severity, and patient survival though the ethnic difference was attenuated (ß, 0.47 [95% CI, -0.17 to 1.12]; P=0.15) after adjustment for trust in the medical profession and frequency of personal prayer. High CollaboRATE scale scores were more common among surrogates of MA patients than NHW individuals (unadjusted odds ratio, 1.75 [95% CI, 1.04-2.95]). This association persisted after adjustment for demographic and clinical factors though there was an interaction between patient age and ethnicity (P=0.04), suggesting that this difference was primarily in older patients. CONCLUSIONS: Surrogate decision-makers of MA patients generally reported better outcomes on validated measures of quality of communication and shared decision-making than NHW individuals. Further study of outcomes among diverse populations of stroke surrogate decision-makers may help to identify sources of strength and resiliency that may be broadly applicable.


Assuntos
Tomada de Decisões , Acidente Vascular Cerebral , Humanos , Idoso , Acidente Vascular Cerebral/terapia , Hemorragia Cerebral , Ordens quanto à Conduta (Ética Médica) , Texas
9.
Stem Cells Int ; 2023: 2826815, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37964983

RESUMO

The latest 2021 WHO classification redefines glioblastoma (GBM) as the hierarchical reporting standard by eliminating glioblastoma, IDH-mutant and only retaining the tumor entity of "glioblastoma, IDH-wild type." Knowing that subclassification of tumors based on molecular features is supposed to facilitate the therapeutic choice and increase the response rate in cancer patients, it is necessary to carry out molecular classification of the newly defined GBM. Although differentiation trajectory inference based on single-cell sequencing (scRNA-seq) data holds great promise for identifying cell heterogeneity, it has not been used in the study of GBM molecular classification. Single-cell transcriptome sequencing data from 10 GBM samples were used to identify molecular classification based on differentiation trajectories. The expressions of identified features were validated by public bulk RNA-sequencing data. Clinical feasibility of the classification system was examined in tissue samples by immunohistochemical (IHC) staining and immunofluorescence, and their clinical significance was investigated in public cohorts and clinical samples with complete clinical follow-up information. By analyzing scRNA-seq data of 10 GBM samples, four differentiation trajectories from the glioblastoma stem cell-like (GSCL) cluster were identified, based on which malignant cells were classified into five characteristic subclusters. Each cluster exhibited different potential drug sensitivities, pathways, functions, and transcriptional modules. The classification model was further examined in TCGA and CGGA datasets. According to the different abundance of five characteristic cell clusters, the patients were classified into five groups which we named Ac-G, Class-G, Neo-G, Opc-G, and Undiff-G groups. It was found that the Undiff-G group exhibited the worst overall survival (OS) in both TCGA and CGGA cohorts. In addition, the classification model was verified by IHC staining in 137 GBM samples to further clarify the difference in OS between the five groups. Furthermore, the novel biomarkers of glioblastoma stem cells (GSCs) were also described. In summary, we identified five classifications of GBM and found that they exhibited distinct drug sensitivities and different prognoses, suggesting that the new grouping system may be able to provide important prognostic information and have certain guiding significance for the treatment of GBM, and identified the GSCL cluster in GBM tissues and described its characteristic program, which may help develop new potential therapeutic targets for GSCs in GBM.

10.
Cerebrovasc Dis ; 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37952527

RESUMO

Background:Brain arteriovenous malformation (bAVM) is an abnormal vascular mass with disordered arteriovenous connection. Endothelial KRAS mutation is common in bAVM. In vivo studies have demonstrated that mutations of KRAS in somatic cells can induce bAVM-like angiogenesis, suggesting that KRAS gene may play a key role in the development and progression of bAVM. Summary:In this article, we will provide a comprehensive review of action mechanisms of KRAS mutations in the development of bAVM and summarize potential targeting drugs for KRAS mutations in bAVM somatic cells. Key Message: KRAS mutation in human brain endothelial cells is a key driver in the pathogenesis of sporadic cerebral arteriovenous malformations. It is of great clinical importance to explore and summarize the changes in the signaling pathway induced by KRAS mutation, which may provide additional targets for the treatment of sporadic bAVM development.

11.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 40(5): 1005-1011, 2023 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-37879931

RESUMO

Transcranial electric stimulation (TES) is a non-invasive, economical, and well-tolerated neuromodulation technique. However, traditional TES is a whole-brain stimulation with a small current, which cannot satisfy the need for effectively focused stimulation of deep brain areas in clinical treatment. With the deepening of the clinical application of TES, researchers have constantly investigated new methods for deeper, more intense, and more focused stimulation, especially multi-electrode stimulation represented by high-precision TES and temporal interference stimulation. This paper reviews the stimulation optimization schemes of TES in recent years and further analyzes the characteristics and limitations of existing stimulation methods, aiming to provide a reference for related clinical applications and guide the following research on TES. In addition, this paper proposes the viewpoint of the development direction of TES, especially the direction of optimizing TES for deep brain stimulation, aiming to provide new ideas for subsequent research and application.


Assuntos
Estimulação Encefálica Profunda , Estimulação Transcraniana por Corrente Contínua , Estimulação Transcraniana por Corrente Contínua/métodos , Encéfalo/fisiologia , Cabeça , Estimulação Elétrica/métodos
12.
Stroke ; 54(9): 2356-2365, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37485665

RESUMO

BACKGROUND: The aim of this study was to characterize change in sleep-disordered breathing severity in the year following stroke, overall, and by ethnicity, within the population-based Brain Attack Surveillance in Corpus Christi Project. METHODS: First-ever ischemic strokes (n=414) were ascertained by active and passive surveillance and validated by stroke-trained physicians. Patients with stroke were invited to participate in portable sleep apnea testing (ApneaLink Plus) at baseline and 3, 6, and 12 months poststroke. Sleep-disordered breathing severity was assessed by the respiratory event index (apneas and hypopneas/hour of recording). The component obstructive apnea index and central apnea index were also assessed. Time and ethnicity effects on outcomes, as well as ethnic differences in time effects, were analyzed using generalized estimating equations with multivariable adjustment for confounding factors. RESULTS: Mean age (n=414) was 63.9 years (SD=10.9); 68.4% were Mexican American. Baseline mean respiratory event index, obstructive apnea index, and central apnea index were 21.3 (SD=16.6), 8.6 (SD=11.5), and 1.5 (SD=3.2), respectively. There was no time effect on respiratory event index (P=0.35) but obstructive apnea index increased over time (P<0.01). Averaged over follow-up, respiratory event index and obstructive apnea index were significantly higher in Mexican American than non-Hispanic White persons. No ethnic difference in the time effect was found for either outcome. For central apnea index, there was an ethnicity-time interaction (P=0.01) such that central apnea index increased in non-Hispanic White but did not change in Mexican American persons. CONCLUSIONS: Sleep-disordered breathing severity was significant and stable for most individuals in the year after stroke. These results do not confirm previous reports of diminishing sleep-disordered breathing severity over time after stroke and would support early assessment and treatment where indicated.


Assuntos
Síndromes da Apneia do Sono , Apneia do Sono Tipo Central , Acidente Vascular Cerebral , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/epidemiologia , Síndromes da Apneia do Sono/diagnóstico , Síndromes da Apneia do Sono/epidemiologia , Síndromes da Apneia do Sono/etiologia , Etnicidade
13.
Mol Psychiatry ; 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37468529

RESUMO

Deep brain regions such as hippocampus, insula, and amygdala are involved in neuropsychiatric disorders, including chronic insomnia and depression. Our recent reports showed that transcranial alternating current stimulation (tACS) with a current of 15 mA and a frequency of 77.5 Hz, delivered through a montage of the forehead and both mastoids was safe and effective in intervening chronic insomnia and depression over 8 weeks. However, there is no physical evidence to support whether a large alternating current of 15 mA in tACS can send electrical currents to deep brain tissue in awake humans. Here, we directly recorded local field potentials (LFPs) in the hippocampus, insula and amygdala at different current strengths (1 to 15 mA) in 11 adult patients with drug-resistant epilepsy implanted with stereoelectroencephalography (SEEG) electrodes who received tACS at 77.5 Hz from 1 mA to 15 mA at 77.5 Hz for five minutes at each current for a total of 40 min. For the current of 15 mA at 77.5 Hz, additional 55 min were applied to add up a total of 60 min. Linear regression analysis revealed that the average LFPs for the remaining contacts on both sides of the hippocampus, insula, and amygdala of each patient were statistically associated with the given currents in each patient (p < 0.05-0.01), except for the left insula of one subject (p = 0.053). Alternating currents greater than 7 mA were required to produce significant differences in LFPs in the three brain regions compared to LFPs at 0 mA (p < 0.05). The differences remained significant after adjusting for multiple comparisons (p < 0.05). Our study provides direct evidence that the specific tACS procedures are capable of delivering electrical currents to deep brain tissues, opening a realistic avenue for modulating or treating neuropsychiatric disorders associated with hippocampus, insula, and amygdala.

14.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 40(3): 401-408, 2023 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-37380377

RESUMO

In transcranial magnetic stimulation (TMS), the conductivity of brain tissue is obtained by using diffusion tensor imaging (DTI) data processing. However, the specific impact of different processing methods on the induced electric field in the tissue has not been thoroughly studied. In this paper, we first used magnetic resonance image (MRI) data to create a three-dimensional head model, and then estimated the conductivity of gray matter (GM) and white matter (WM) using four conductivity models, namely scalar (SC), direct mapping (DM), volume normalization (VN) and average conductivity (MC), respectively. Isotropic empirical conductivity values were used for the conductivity of other tissues such as the scalp, skull, and cerebrospinal fluid (CSF), and then the TMS simulations were performed when the coil was parallel and perpendicular to the gyrus of the target. When the coil was perpendicular to the gyrus where the target was located, it was easy to get the maximum electric field in the head model. The maximum electric field in the DM model was 45.66% higher than that in the SC model. The results showed that the conductivity component along the electric field direction of which conductivity model was smaller in TMS, the induced electric field in the corresponding domain corresponding to the conductivity model was larger. This study has guiding significance for TMS precise stimulation.


Assuntos
Imagem de Tensor de Difusão , Estimulação Magnética Transcraniana , Condutividade Elétrica , Eletricidade , Couro Cabeludo
15.
Small ; 19(38): e2303228, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37194983

RESUMO

High actuation performance of a moisture actuator highly depends on the presence of a large property difference between the two layers, which may cause interfacial delamination. Improving interfacial adhesion strength while increasing the difference between the layers is a challenge. In this study, a moisture-driven tri-layer actuator with a Yin-Yang-interface (YYI) design is investigated in which a moisture-responsive polyacrylamide (PAM) hydrogel layer (Yang) is combined with a moisture-inert polyethylene terephthalate (PET) layer (Yin) using an interfacial poly(2-ethylhexyl acrylate) (PEA) adhesion layer. Fast and large reversible bending, oscillation, and programmable morphing motions in response to moisture are realized. The response time, bending curvature, and response speed normalized by thickness are among the best compared with those of previously reported moisture-driven actuators. The excellent actuation performance of the actuator has potential multifunctional applications in moisture-controlled switches, mechanical grippers, and crawling and jumping motions. The Yin-Yang-interface design proposed in this work provides a new design strategy for high-performance intelligent materials and devices.

16.
Aging Dis ; 14(6): 2284-2302, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37199734

RESUMO

The classification of microglial M1/M2 polarization in the acute phase of ischemic stroke remains controversial, which has limited further advances in neuroprotective strategy. To thoroughly assess the microglial phenotypes, we made the middle cerebral artery occlusion model in mice to simulate the acute pathological processes of ischemic stroke from normal conditions to acute cerebral ischemia and then to the early reperfusion period. The temporal changes in gene profiles, cell subtypes, and microglial function were comprehensively analyzed using single-cell RNA sequencing. We identified 37,614 microglial cells and divided them into eight distinct subpopulations. Mic_home, Mic_pre1, and Mic_pre2 subpopulations were three clusters mainly composed of cells from the control samples, in which Mic_home was a homeostatic subpopulation characterized by high expression of Hpgd and Tagap, and Mic_pre1 and Mic_pre2 were two clusters with preliminary inflammatory activation characteristics marked by P2ry13 and Wsb1 respectively. Mic_M1L1 and Mic_M1L2 subpopulations exhibited M1-like polarization manifested by the upregulation of inflammatory genes after ischemic stroke, while the intrinsic heterogeneity on the level of inflammatory responses and neurotrophic support properties was observed. Moreover, we identified three unique clusters of cells with low inflammation levels. Mic_np1, Mic_np2, and Mic_np3 were characterized by high expression of Arhgap45, Rgs10, and Pkm respectively. However, these cells did not show significant M2-like characteristics and their classic microglia function was also attenuated. These subpopulations exhibited higher activation of neuropeptide functional pathways. At last, we performed cell-cell communication analysis and identified major couplings contributing to the interaction between microglia and other cell populations. In summary, our study elucidated the temporal heterogeneity of microglia in the acute phase of ischemic stroke, which may facilitate the identification of effective neuroprotective targets to curb ischemic damage at an early stage.

17.
Neurology ; 101(9): 407-411, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37045598

RESUMO

OBJECTIVES: We examined whether language preference was associated with 90-day poststroke outcomes among Mexican American (MA) patients. METHODS: Patients with ischemic stroke and intracerebral hemorrhage from the population-based Brain Attack Surveillance in Corpus Christi project (2009-2018) were compared by language preference in 90-day neurologic, functional, and cognitive outcomes using weighted Tobit regression. Models were adjusted for demographics, initial NIH Stroke Scale (NIHSS), medical history, stroke characteristics, and insurance status. RESULTS: Of 1,096 stroke patients, 926 were English-speaking and 170 were Spanish-only-speaking. Spanish speakers were older (p < 0.01), received less education (p < 0.01), had higher initial NIHSS values (p = 0.02), had higher prevalence of atrial fibrillation (p < 0.01), and had lower prevalence of smoking (p = 0.01) than English speakers. In fully adjusted models, Spanish-only speakers had worse neurologic outcome (NIHSS, range 0-44 [higher worse], mean difference: 1.93, p < 0.01) but no difference in functional outcome measured by activities of daily living/instrumental activities of daily living or cognitive outcome compared with English speakers. DISCUSSION: This population-based study found worse neurologic but similar functional and cognitive stroke outcomes among Spanish-only-speaking MA patients compared with English-speaking MA patients.


Assuntos
Americanos Mexicanos , Acidente Vascular Cerebral , Humanos , Atividades Cotidianas , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/terapia , Hispânico ou Latino , Idioma
18.
EBioMedicine ; 90: 104509, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36905783

RESUMO

BACKGROUND: Intraplaque haemorrhage (IPH) drives atherosclerosis progression and is a key imaging biomarker of unstable plaques. Non-invasive and sensitive monitoring of IPH is challenging due to the compositional complexity and dynamic nature of atherosclerotic plaques. Magnetic particle imaging (MPI) is a highly sensitive, radiation-free, and no-tissue-background tomographic technique that detects superparamagnetic nanoparticles. Thus, we aimed to investigate whether MPI can in vivo detect and monitor IPH. METHODS: Thirty human carotid endarterectomy samples were collected and scanned with MPI. The tandem stenosis (TS) model was employed to establish unstable plaques with IPH in ApoE-/- mice. MPI and 7 T T1-weighted magnetic resonance imaging (MRI) were performed on TS ApoE-/- mice. Plaque specimens were analyzed histologically. FINDINGS: Human carotid endarterectomy samples exhibited endogenous MPI signals, which histologically colocalized with IPH. In vitro experiments identified haemosiderin, a haemoglobin degradation product, as a potential source of MPI signals. Longitudinal MPI of TS ApoE-/- mice detected IPH at unstable plaques, of which MPI signal-to-noise ratio values increased from 6.43 ± 1.74 (four weeks) to 10.55 ± 2.30 (seven weeks) and reduced to 7.23 ± 1.44 (eleven weeks). In contrast, 7 T T1-weighted MRI did not detect the small-size IPH (329.91 ± 226.82 µm2) at four weeks post-TS. The time-course changes in IPH were shown to correlate with neovessel permeability providing a possible mechanism for signal changes over time. INTERPRETATION: MPI is a highly sensitive imaging technology that allows the identification of atherosclerotic plaques with IPH and may help detect and monitor unstable plaques in patients. FUNDING: This work was supported in part by the Beijing Natural Science Foundation under Grant JQ22023; the National Key Research and Development Program of China under Grant 2017YFA0700401; the National Natural Science Foundation of China under Grant 62027901, 81827808, 81730050, 81870178, 81800221, 81527805, and 81671851; the CAS Youth Innovation Promotion Association under Grant Y2022055 and CAS Key Technology Talent Program; and the Project of High-Level Talents Team Introduction in Zhuhai City (Zhuhai HLHPTP201703).


Assuntos
Aterosclerose , Estenose das Carótidas , Placa Aterosclerótica , Humanos , Animais , Camundongos , Adolescente , Placa Aterosclerótica/patologia , Artérias Carótidas/patologia , Estenose das Carótidas/patologia , Imageamento por Ressonância Magnética , Hemorragia/diagnóstico por imagem , Aterosclerose/diagnóstico por imagem , Aterosclerose/patologia , Hemoglobinas
19.
Chem Soc Rev ; 52(7): 2377-2390, 2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-36919405

RESUMO

Twisted-fiber artificial muscles, a new type of soft actuator, exhibit significant potential for use in applications related to lightweight smart devices and soft robotics. Fiber twisting generates internal torque and a spiral architecture, exhibiting rotation, contraction, or elongation as a result of fiber volume change. Untethering a twisted fiber often results in fiber untwisting and loss of stored torque energy. Preserving the torque in twisted fibers during actuation is necessary to realize a reversible and stable artificial muscle performance; this is a key issue that has not yet been systematically discussed and reviewed. This review summarizes the mechanisms for preserving the torque within twisted fibers and the potential applications of such systems. The potential challenges and future directions of research related to twisted-fiber artificial muscles are also discussed.

20.
Metab Eng ; 76: 110-119, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36746296

RESUMO

p-Hydroxyacetophenone (p-HAP) and its glucoside picein are plant-derived natural products that have been extensively used in chemical, pharmaceutical and cosmetic industries owing to their antioxidant, antibacterial and antiseptic activities. However, the natural biosynthetic pathways for p-HAP and picein have yet been resolved so far, limiting their biosynthesis in microorganisms. In this study, we design and construct a biosynthetic pathway for de novo production of p-HAP and picein from glucose in E. coli. First, screening and characterizing pathway enzymes enable us to successfully establish functional biosynthetic pathway for p-HAP production. Then, the rate-limiting step in the pathway caused by a reversible alcohol dehydrogenase is completely eliminated by modulating intracellular redox cofactors. Subsequent host strain engineering via systematic increase of precursor supplies enables production enhancement of p-HAP with a titer of 1445.3 mg/L under fed-batch conditions. Finally, a novel p-HAP glucosyltransferase capable of generating picein from p-HAP is identified and characterized from a series of glycosyltransferases. On this basis, de novo biosynthesis of picein from glucose is achieved with a titer of 210.7 mg/L under fed-batch conditions. This work not only demonstrates a microbial platform for p-HAP and picein synthesis, but also represents a generalizable pathway design strategy to produce value-added compounds.


Assuntos
Vias Biossintéticas , Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , Vias Biossintéticas/genética , Glucosídeos/genética , Glucose/genética , Glucose/metabolismo , Engenharia Metabólica
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