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1.
Opt Express ; 32(10): 16970-16982, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38858891

RESUMO

Laser-induced plasma micromachining (LIPMM) is an advanced technology that utilizes the plasma generated from laser breakdown to remove material, thereby facilitating the fabrication of microstructures. This paper explores the use of LIPMM on 304 stainless steel surfaces parallel to the laser beam in different solutions, focusing on the impact of the liquid environment on the machining process. It presents a theoretical analysis of the material removal mechanisms unique to this orientation and experimentally investigates how water, a salt solution, and ethanol affect plasma shockwave characteristics. Notably, the plasma shockwave in the salt solution demonstrates the most significant peak pressure and energy, enhancing the micromachining efficiency. These findings suggest that varying the liquid environment can significantly influence LIPMM's effectiveness, offering potential improvements in precision and control. This study broadens the understanding of LIPMM applications, especially in orientations not commonly explored, and opens new possibilities for advanced micromachining techniques in various industrial applications.

2.
Crit Care ; 28(1): 260, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39095884

RESUMO

BACKGROUND: This study aimed to explore the characteristics of abnormal regional resting-state functional magnetic resonance imaging (rs-fMRI) activity in comatose patients in the early period after cardiac arrest (CA), and to investigate their relationships with neurological outcomes. We also explored the correlations between jugular venous oxygen saturation (SjvO2) and rs-fMRI activity in resuscitated comatose patients. We also examined the relationship between the amplitude of the N20-baseline and the rs-fMRI activity within the intracranial conduction pathway of somatosensory evoked potentials (SSEPs). METHODS: Between January 2021 and January 2024, eligible post-resuscitated patients were screened to undergo fMRI examination. The amplitude of low-frequency fluctuation (ALFF), fractional ALFF (fALFF), and regional homogeneity (ReHo) of rs-fMRI blood oxygenation level-dependent (BOLD) signals were used to characterize regional neural activity. Neurological outcomes were evaluated using the Glasgow-Pittsburgh cerebral performance category (CPC) scale at 3 months after CA. RESULTS: In total, 20 healthy controls and 31 post-resuscitated patients were enrolled in this study. The rs-fMRI activity of resuscitated patients revealed complex changes, characterized by increased activity in some local brain regions and reduced activity in others compared to healthy controls (P < 0.05). However, the mean ALFF values of the whole brain were significantly greater in CA patients (P = 0.011). Among the clusters of abnormal rs-fMRI activity, the cluster values of ALFF in the left middle temporal gyrus and inferior temporal gyrus and the cluster values of ReHo in the right precentral gyrus, superior frontal gyrus and middle frontal gyrus were strongly correlated with the CPC score (P < 0.001). There was a strong correlation between the mean ALFF and SjvO2 in CA patients (r = 0.910, P < 0.001). The SSEP N20-baseline amplitudes in CA patients were negatively correlated with thalamic rs-fMRI activity (all P < 0.001). CONCLUSIONS: This study revealed that abnormal rs-fMRI BOLD signals in resuscitated patients showed complex changes, characterized by increased activity in some local brain regions and reduced activity in others. Abnormal BOLD signals were associated with neurological outcomes in resuscitated patients. The mean ALFF values of the whole brain were closely related to SjvO2 levels, and changes in the thalamic BOLD signals correlated with the N20-baseline amplitudes of SSEP responses. TRIAL REGISTRATION: NCT05966389 (Registered July 27, 2023).


Assuntos
Coma , Parada Cardíaca , Imageamento por Ressonância Magnética , Sobreviventes , Humanos , Masculino , Feminino , Imageamento por Ressonância Magnética/métodos , Estudos Prospectivos , Pessoa de Meia-Idade , Coma/fisiopatologia , Coma/diagnóstico por imagem , Parada Cardíaca/complicações , Parada Cardíaca/fisiopatologia , Idoso , Sobreviventes/estatística & dados numéricos , Estudos de Coortes , Descanso/fisiologia , Adulto
3.
EMBO Rep ; 22(9): e52252, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34288348

RESUMO

Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (Mtb) that places a heavy strain on public health. Host susceptibility to Mtb is modulated by macrophages, which regulate the balance between cell apoptosis and necrosis. However, the role of molecular switches that modulate apoptosis and necrosis during Mtb infection remains unclear. Here, we show that Mtb-susceptible mice and TB patients have relatively low miR-342-3p expression, while mice with miR-342-3p overexpression are more resistant to Mtb. We demonstrate that the miR-342-3p/SOCS6 axis regulates anti-Mtb immunity by increasing the production of inflammatory cytokines and chemokines. Most importantly, the miR-342-3p/SOCS6 axis participates in the switching between Mtb-induced apoptosis and necrosis through A20-mediated K48-linked ubiquitination and RIPK3 degradation. Our findings reveal several strategies by which the host innate immune system controls intracellular Mtb growth via the miRNA-mRNA network and pave the way for host-directed therapies targeting these pathways.


Assuntos
MicroRNAs , Mycobacterium tuberculosis , Tuberculose , Animais , Morte Celular , Humanos , Inflamação/genética , Camundongos , MicroRNAs/genética , Mycobacterium tuberculosis/genética , Proteínas Supressoras da Sinalização de Citocina , Tuberculose/genética
4.
BMC Cardiovasc Disord ; 23(1): 191, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-37046189

RESUMO

We explored the effect of thrombin on human aortic smooth muscle cells (HASMCs) and further analyzed its role in the pathogenesis of atherosclerosis (AS). Thrombin-induced differentially expressed genes (DEGs) in HASMCs were identified by analyzing expression profiles from the GEO. Subsequently, enrichment analysis, GSEA, PPI network, and gene-microRNAs networks were interrogated to identify hub genes and associated pathways. Enrichment analysis results indicated that thrombin causes HASMCs to secrete various pro-inflammatory cytokines and chemokines, exacerbating local inflammatory response in AS. Moreover, we identified 9 HUB genes in the PPI network, which are closely related to the inflammatory response and the promotion of the cell cycle. Additionally, we found that thrombin inhibits lipid metabolism and autophagy of HASMCs, potentially contributing to smooth muscle-derived foam cell formation. Our study deepens a mechanistic understanding of the effect of thrombin on HASMCs and provides new insight into treating AS.


Assuntos
Aterosclerose , Transcriptoma , Humanos , Trombina/genética , Trombina/metabolismo , Trombina/farmacologia , Aterosclerose/patologia , Miócitos de Músculo Liso/metabolismo , Músculo Liso/metabolismo , Músculo Liso/patologia
5.
Artigo em Inglês | MEDLINE | ID: mdl-38064630

RESUMO

Objective: To observe the effects of traditional Chinese medicine (TCM) five-element music therapy combined with mirtazapine on depression and limb function recovery after ischemic stroke. Methods: A total of 110 patients treated in the Departments of Geriatrics, Cardiology, and Psychology of three hospitals in Qinhuangdao City, Hebei Province, China from October 2022 to August 2023 were selected. Based on the scores of 24-item Hamilton Depression Scale (HAMD-24), Barthel (BL) index, and National Institute of Health Stroke Scale (NIHSS) before enrollment, the patients were randomly divided into control group (n = 58) and experimental group (n = 52). The patients in control group were treated with limb rehabilitation, while those in experimental group underwent limb rehabilitation combined with five-element music therapy and mirtazapine. Results: After 12 weeks of treatment and observation, 11 patients in control group and 9 patients in experimental group withdrew from this trail. As for the proportions of score changes, experimental group had higher decline proportions of HAMD-24 score and NIHSS score as well as an increased proportion of BL index score than control group, which were 43.97%, 69.32%, and 44.12%, respectively. Conclusion: TCM five-element music therapy combined with mirtazapine significantly improves depression and limb function recovery after ischemic stroke.

6.
BMC Musculoskelet Disord ; 23(1): 507, 2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35643440

RESUMO

BACKGROUND: Pain catastrophizing in preoperative total knee arthroplasty (TKA) patients is associated with several poorly characterised factors in the literature. This study investigated the current state and associated factors of preoperative pain catastrophizing in patients undergoing TKA. METHODS: This descriptive cross-sectional study was conducted at the orthopedics ward of two tertiary hospitals in Lanzhou, China. Pain catastrophizing was measured using the Chinese versions of the Pain Catastrophizing Scale, Short Form-36 (physical function domain), Numerical Rating Scale, Oxford Knee Score, Hospital Anxiety and Depression Scale, and Life Orientation Test-Revised. RESULTS: The study included 360 participants. Preoperative TKA pain catastrophizing in all patients was high, with a mean score of 24.92 (SD: 12.38). The stepwise multiple linear regression analysis revealed anxiety (ß = 0.548, P < 0.01), education level (ß = - 0.179, P < 0.01), physical function (ß = - 0.156, P < 0.01), and pain intensity during activity (ß = 0.105, P = 0.015) as associated factors for pain catastrophizing, possibly explaining 51.2% of the total variation (F = 95.149, P < 0.01). CONCLUSION: Anxiety was the most relevant factor for pain catastrophizing in patients with preoperative TKA. Lower education levels, poor physical function, and stronger pain intensity during the activity were also associated with pain catastrophizing.


Assuntos
Artroplastia do Joelho , Osteoartrite do Joelho , Artroplastia do Joelho/efeitos adversos , Catastrofização , China/epidemiologia , Estudos Transversais , Humanos , Osteoartrite do Joelho/complicações , Dor/cirurgia
7.
Langmuir ; 37(49): 14314-14322, 2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34865489

RESUMO

Inspired by natural creatures, superhydrophobic surfaces with various adhesion behaviors have attracted significant scientific interest. In this study, by controlling the laser fluence, the scanning times, and the subsequent cleaning method, microcolumn arrays with different morphologies were fabricated on 304 stainless-steel surfaces using picosecond laser direct writing. To achieve wettability transition, the laser-processed samples were then subjected to heat treatments (120 °C) in air and in a low vacuum environment (6 kPa). The results show that after heat treatment in different environments and with various time lengths, the laser-processed surfaces become hydrophobic surfaces with different adhesion properties. It is worth noting that while surfaces heat-treated in air exhibit weak wettability transition potential and high adhesion, the surfaces heat-treated in a low vacuum environment present superhydrophobic and low adhesion properties with a minimum sliding angle of about 3.14°. Moreover, the low-vacuum heat-treated surfaces retain good superhydrophobic properties after 1 month of observation as well as an abrasion test. These transitions in hydrophobic behavior and adhesion properties may be mainly attributed to the heat treatment-induced (in the air or in a low vacuum environment) redistribution of surface compounds and the microstructure-induced alternation of the solid-liquid contact state. By controlling the laser processing parameters and the heat treatment time and environment, stable wettability transition and flexible adhesion control of stainless steel can be easily achieved.

8.
Opt Express ; 26(5): 6325-6330, 2018 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-29529824

RESUMO

The formation of periodic structures on stainless steel under linearly polarized multi-burst picosecond laser pulses irradiation was experimentally investigated. The resulting structures were characterized by scanning electron microscopy (SEM) analysis. This analysis of images revealed four distinctive (quasi-) periodic structures depending on the laser irradiation parameters, i.e., LSFLs, HSFLs, micro-grooves and nano-holes. It is demonstrated that the multi-burst picosecond pulses technique is capable of fabricating periodic structures with different scales and shapes.

9.
Opt Express ; 26(15): 18998-19008, 2018 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-30114160

RESUMO

Ordered hierarchical structures were fabricated on a stainless steel surface using a single picosecond laser for highly controllable dimensions. Picosecond laser induced periodic structures were firstly used to create large-scale nano-structures with a period of ~450 nm. Subsequently, laser direct writing, by simply changing process parameters was employed to create micro squared structures with 19 µm width, 19 µm interval and 3-7.5 µm depth on the previously created nano-structures. As a result, micro squared structures covered by uniform nano-structures, similar to examples present in nature, were successfully fabricated. Additionally, the wettability of the created hierarchical structures was analyzed. The results demonstrated that the combination of both micro- and nano-structures allowed to tune the wetting behavior, presenting a great potential for wettability applications.

10.
Proc Natl Acad Sci U S A ; 112(15): E1908-15, 2015 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-25825747

RESUMO

In bacteria, certain shape-sensing proteins localize to differently curved membranes. During sporulation in Bacillus subtilis, the only convex (positively curved) surface in the cell is the forespore, an approximately spherical internal organelle. Previously, we demonstrated that SpoVM localizes to the forespore by preferentially adsorbing onto slightly convex membranes. Here, we used NMR and molecular dynamics simulations of SpoVM and a localization mutant (SpoVM(P9A)) to reveal that SpoVM's atypical amphipathic α-helix inserts deeply into the membrane and interacts extensively with acyl chains to sense packing differences in differently curved membranes. Based on binding to spherical supported lipid bilayers and Monte Carlo simulations, we hypothesize that SpoVM's membrane insertion, along with potential cooperative interactions with other SpoVM molecules in the lipid bilayer, drives its preferential localization onto slightly convex membranes. Such a mechanism, which is distinct from that used by high curvature-sensing proteins, may be widely conserved for the localization of proteins onto the surface of cellular organelles.


Assuntos
Bacillus subtilis/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Membrana Celular/metabolismo , Estrutura Secundária de Proteína , Bacillus subtilis/genética , Proteínas de Bactérias/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Bicamadas Lipídicas/metabolismo , Espectroscopia de Ressonância Magnética , Microscopia de Fluorescência , Simulação de Dinâmica Molecular , Método de Monte Carlo , Mutação , Ligação Proteica
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