Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 75
Filtrar
1.
Polymers (Basel) ; 16(12)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38931999

RESUMO

Thermosetting polymers and composites are a class of high-performance materials with significant industrial applications. However, the widespread use of thermosets and their composites generates large quantities of waste and leads to serious economic and environmental problems, there is a critical need in the elaboration of sustainable composite materials. Here, we propose a method to prepare sustainable carbon fiber reinforced composites with different degrees of greenness by blending environmentally friendly EIA with DGEBA in different ratios, and the properties compared with a well-known commercial petroleum-based epoxy resin. The prepared carbon fiber reinforced polymer (CFRP) composites with different degrees of greenness had excellent dimensional stability under extreme hygrothermal aging. After aging, the green CFRP composite T700/EIA-30 has higher strength and performance retention than that of petroleum-based CFRP composites. The higher hygrothermal stability and durability of EIA-based epoxy resins as compared with BPA-based epoxy resins demonstrated significant evidence to design and develop a novel bio-based epoxy resin with high performance to substitute the petroleum-based epoxy resin.

3.
BMC Nurs ; 23(1): 392, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849821

RESUMO

AIM: To explore the views and experiences of formal caregivers caring for older inpatients with physical disabilities. METHODS: It was a qualitative phenomenological study. Using purposive sampling, twelve formal caregivers were chosen in a tertiary comprehensive hospital in Hangzhou, China. Semi-structured, face-to-face interviews were conducted, guided by open-ended questions that focused on gaining rich insights into participants' views and experiences. Coding reliability thematic analysis was used to guide data analysis and categorize, based on Lazarus and Folkman's theory of transactional coping. RESULTS: Four themes emerged from the data analysis: (1) Caregiving Threats. (2) motivations. (3) Responsibility Management. (4) Fear. CONCLUSION: Despite facing significant pressure at work, formal caregivers of elderly inpatients with physical disabilities possess the drive and various coping strategies to excel in their role. Identifying caregivers' experiences of care can be helpful in improving resilience to stress and maintaining stability in formal caregivers.

4.
Front Plant Sci ; 15: 1349202, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38855464

RESUMO

Introduction: Arbuscular mycorrhizal fungi (AMF) and dark septate endophytic fungi (DSEs) generally coexist in the roots of plants. However, our understanding of the effects of their coexistence on plant growth and stress resistance is limited. Methods: In the present study, the effects of single and dual inoculation of AMF and DSE on the growth, photosynthetic physiology, glutathione (GSH) metabolism, endogenous hormones, and cadmium (Cd) content of maize under 25 mg•kg-1 Cd stress were investigated. Results: Compared with that after the non-inoculation treatment, AMF+DSE co-inoculation significantly increased the photosynthetic rate (Pn) of maize leaves; promoted root GSH metabolism; increased the root GSH concentration and activity of γ-glutamyl cysteine synthase (γ-GCS), ATP sulfatase (ATPS) and sulfite reductase (SIR) by 215%, 117%, 50%, and 36%, respectively; and increased the concentration of endogenous hormones in roots, with increases in zeatin (ZR), indole-3 acetic acid (IAA), and abscisic acid (ABA) by 81%, 209%, and 72%, respectively. AMF inoculation, DSE inoculation and AMF+DSE co-inoculation significantly increased maize biomass, and single inoculation with AMF or DSE increased the Cd concentration in roots by 104% or 120%, respectively. Moreover, significant or highly significant positive correlations were observed between the contents of ZR, IAA, and ABA and the activities of γ-GCS, ATPS, and SIR and the glutathione (GSH) content. There were significant or highly significant positive interactions between AMF and DSE on the Pn of leaves, root GSH metabolism, and endogenous hormone contents according to two-way analysis of variance. Therefore, the coexistence of AMF and DSE synergistically enhanced the Cd tolerance of maize.

5.
Front Endocrinol (Lausanne) ; 15: 1386142, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38883598

RESUMO

Background: Limited studies have investigated the relationship between systemic oxidative stress and inflammatory bowel disease (IBD). The purpose of this study was to explore the relationship between oxidative balance score (OBS) and IBD. Methods: We included 175,808 participants from the UK Biobank database from 2006 to 2010. OBS scores were calculated based on 22 lifestyle and dietary factors. Multiple variable Cox proportional regression models, as well as gender stratification and subgroup analysis, were utilized to investigate the relationship between OBS and IBD. Results: There is a significant negative correlation between OBS and the occurrence of IBD, ulcerative colitis (UC), and Crohn's disease (CD). Additionally, OBS is significantly negatively correlated with intestinal obstruction in CD patients. Gender stratified analysis suggest a significant correlation between OBS and CD in female patients, particularly pronounced in those under 60 years old. Sensitivity analysis indicates a significant negative correlation between lifestyle-related OBS and diet-related OBS with the occurrence of CD in females, diet-related OBS is negatively correlated with CD in males. Conclusion: OBS showed a significant negative correlation with IBD, especially in female CD patients. This study underscores the importance of antioxidant diet and lifestyle, which may provide a greater advantage for female CD patients.


Assuntos
Antioxidantes , Doenças Inflamatórias Intestinais , Estresse Oxidativo , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Antioxidantes/metabolismo , Adulto , Doenças Inflamatórias Intestinais/metabolismo , Idoso , Estilo de Vida , Doença de Crohn/metabolismo , Colite Ulcerativa/metabolismo , Dieta
6.
Front Endocrinol (Lausanne) ; 15: 1397512, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38745951

RESUMO

Background: The Oxidative Balance Score (OBS) is commonly used to assess oxidative stress and provides a comprehensive evaluation of dietary and lifestyle-related exposures. However, there is limited research on the association between OBS and colorectal cancer (CRC), its subsites, and complications. The objective of this study was to assess the relationship between OBS and the risk of CRC, its subsites, and common complications in a large prospective cohort study. Methods: We included data from 175,808 participants in the UK Biobank data sample repository from 2006 to 2010. We evaluated OBS using a scoring system based on 22 dietary and lifestyle factors. Multiple adjustments, including multivariate Cox proportional hazard regression, gender stratification, subgroup analysis, and sensitivity analysis, were performed to fully explore the relationship between OBS and CRC, its subsites, and complications. The mediation analysis was conducted to investigate whether serum albumin, uric acid, and neutrophil levels mediate the relationship between OBS and CRC. Results: After adjusting for potential confounding factors, a significant negative correlation was found between OBS and the risk of CRC and its subsites (proximal colon cancer, distal colon cancer, and rectal cancer). This correlation was particularly pronounced in male CRC patients. Serum albumin, uric acid, and neutrophil count, which are biomarkers, were found to have a significant mediating effect between OBS and CRC. Conclusion: Our study suggests that higher exposure to antioxidants assessed through OBS (diet and lifestyle rich in antioxidants) may decrease the occurrence of CRC and its subsites.


Assuntos
Neoplasias Colorretais , Estresse Oxidativo , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/prevenção & controle , Neoplasias Colorretais/sangue , Estudos Prospectivos , Incidência , Idoso , Fatores de Risco , Estilo de Vida , Adulto , Dieta , Ácido Úrico/sangue , Reino Unido/epidemiologia , Seguimentos
7.
Hum Brain Mapp ; 45(8): e26712, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38798104

RESUMO

The aim of this study was to systematically investigate structural and functional alterations in amygdala subregions using multimodal magnetic resonance imaging (MRI) in patients with tinnitus with or without affective dysfunction. Sixty patients with persistent tinnitus and 40 healthy controls (HCs) were recruited. Based on a questionnaire assessment, 26 and 34 patients were categorized into the tinnitus patients with affective dysfunction (TPAD) and tinnitus patients without affective dysfunction (TPWAD) groups, respectively. MRI-based measurements of gray matter volume, fractional anisotropy (FA), fractional amplitude of low-frequency fluctuations (fALFF), regional homogeneity (ReHo), degree centrality (DC), and functional connectivity (FC) were conducted within 14 amygdala subregions for intergroup comparisons. Associations between the MRI properties and clinical characteristics were estimated via partial correlation analyses. Compared with that of the HCs, the TPAD and TPWAD groups exhibited significant structural and functional changes, including white matter integrity (WMI), fALFF, ReHo, DC, and FC alterations, with more pronounced WMI changes in the TPAD group, predominantly within the left auxiliary basal or basomedial nucleus (AB/BM), right central nucleus, right lateral nuclei (dorsal portion), and left lateral nuclei (ventral portion containing basolateral portions). Moreover, the TPAD group exhibited decreased FC between the left AB/BM and left middle occipital gyrus and right superior frontal gyrus (SFG), left basal nucleus and right SFG, and right lateral nuclei (intermediate portion) and right SFG. In combination, these amygdalar alterations exhibited a sensitivity of 65.4% and specificity of 96.9% in predicting affective dysfunction in patients with tinnitus. Although similar structural and functional amygdala remodeling were observed in the TPAD and TPWAD groups, the changes were more pronounced in the TPAD group. These changes mainly involved alterations in functionality and white matter microstructure in various amygdala subregions; in combination, these changes could serve as an imaging-based predictor of emotional disorders in patients with tinnitus.


Assuntos
Tonsila do Cerebelo , Imageamento por Ressonância Magnética , Zumbido , Humanos , Zumbido/diagnóstico por imagem , Zumbido/fisiopatologia , Zumbido/patologia , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/patologia , Tonsila do Cerebelo/fisiopatologia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Substância Cinzenta/fisiopatologia , Transtornos do Humor/diagnóstico por imagem , Transtornos do Humor/etiologia , Transtornos do Humor/fisiopatologia , Transtornos do Humor/patologia
8.
J Clin Nurs ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38572996

RESUMO

BACKGROUND: Older hospitalised patients have low levels of physical activity and multiple impairing factors. AIMS: To systematically evaluate the perceived barriers to physical activity among older patients during hospitalisation, and provide reference for future intervention programs. DESIGN: Following ENTREQ, do a systematic evaluation and synthesis of qualitative investigations. METHODS: An exhaustive exploration was conducted across the CNKI, Wanfang Database, VIP Database, China Biomedical Literature Database, PubMed, Embase, Cochrane Library and Web of Science from their inception until August, 2023 to identify qualitative research on obstacles to physical activity among older hospital patients. The quality of the literature was evaluated using the Joanna Briggs Institute's critical appraisal tool for qualitative research. Meta-synthesis method was used to integrate the results. RESULTS: In total, 8 literatures were included, 43 themes were extracted, and analogous research results were amalgamated to generate 10 categories and 3 syntheses: individual level, interpersonal influencing factors and hospital environment and resources level. CONCLUSION: Older inpatients are faced with multiple barriers to physical activity. Medical staff should pay attention to changes in physical activity during hospitalisation, identify barriers to physical activity in older inpatients and provide references for promoting physical activity programs for the older. NO PATIENT OR PUBLIC CONTRIBUTION: This study is a meta-synthesis and does not require relevant contributions from patients or the public. WHAT IS ALREADY KNOWN: Older patients are at low physical activity levels during hospitalisation. Older inpatients are faced with multiple barriers to physical activity. WHAT THIS PAPER ADDS: Factors of physical activity impairment in hospitalised older patients should be considered in the context of health status, psychological factors, motivation and social support. Disease-induced psychological fallout has a greater impact on physical activity in the older.

9.
Med Sci Monit ; 30: e942687, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38439525

RESUMO

BACKGROUND Sleep disorders are a common disease faced by people today and can lead to fatigue, lack of concentration, impaired memory, and even death. In recent years, the development of brain stimulation techniques has provided a new perspective for the treatment of sleep disorders. However, there is a lack of bibliometric analyses related to sleep disorders and brain stimulation techniques. Therefore, this study analyzed the application status and trend of brain stimulation technology in sleep disorder research. MATERIAL AND METHODS Articles and reviews published between 1999 and 2023 were retrieved from the Web of Science. CiteSpace was used to visually analyze the publications, countries, institutions, journals, authors, references, and keywords. RESULTS A total of 459 publications were obtained. The number of studies was shown to be on a general upward trend. The country with the largest number of publications was the United States; UDICE-French Research Universities had the highest number of publications; Neurology had the highest citation frequency; 90% of the top 10 references cited were from Journal Citation Reports Q1; Brigo was the author with the highest number of publications; and the most frequent keywords were "transcranial magnetic stimulation", "deep brain stimulation", and "Parkinson disease". CONCLUSIONS Our study used CiteSpace software to analyze 459 studies published since 1999 on brain stimulation techniques for the treatment of sleep disorders, revealing research trends and the current state of the field. Our results will help researchers to understand the existing research quickly and provide direction for future research.


Assuntos
Bibliometria , Transtornos do Sono-Vigília , Humanos , Fadiga , Transtornos do Sono-Vigília/terapia , Tecnologia , Encéfalo
10.
Front Immunol ; 15: 1359540, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469291

RESUMO

Background and aims: Inflammatory bowel disease (IBD), mainly categorized into Crohn's disease (CD) and ulcerative colitis (UC), is a chronic relapsing gastrointestinal disorder that significantly impairs patients' quality of life. IBD patients often experience comorbidities such as anxiety and depression, and the underlying mechanisms and treatment strategies remain areas of investigation. Methods: We conducted a Mendelian randomization(MR) analysis utilizing brain image derived phenotypes (IDP) from the UK Biobank database to investigate the causal relationships between IBD and alterations in brain structural morphology and connectivity of neural tracts. This study aimed to identify biological evidence linking IBD to psychiatric disorders such as anxiety and depression. Results: Specifically, the volume of grey matter in the Left Frontal Orbital Cortex exhibited a negative association with the onset of Crohn's disease (odds ratio (OR) [95% confidence interval (CI)]: 0.315[0.180~0.551], adjusted P=0.001), while the volume of the superior frontal cortex in the right hemisphere showed a positive correlation with the development of Ulcerative colitis (OR [95% CI]: 2.285[1.793~2.911], adjusted P<0.001), and the volume of lateral occipital cortex in the left hemisphere demonstrated a positive relationship with Crohn's disease onset (OR [95% CI]: 1.709[1.671~1.747], adjusted P<0.001). In the context of reverse causality, the onset of UC or CD has led to alterations in imaging derived phenotypes associated with five disorders (anxiety, depression, schizophrenia, bipolar disorder, pain) and three functions (memory, emotion, language). Conclusion: Our study has demonstrated a causal relationship between IBD and IDPs. IDPs may serve as potential biomarkers for the progression of IBD and as predictive intermediaries for the development of neurological diseases in IBD patients.


Assuntos
Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Humanos , Qualidade de Vida , Encéfalo/diagnóstico por imagem , Biomarcadores , Fenótipo , Neuroimagem
11.
Artigo em Inglês | MEDLINE | ID: mdl-38437147

RESUMO

Using functional connectivity (FC) or effective connectivity (EC) alone cannot effectively delineate brain networks based on functional magnetic resonance imaging (fMRI) data, limiting the understanding of the mechanism of tinnitus and its treatment. Investigating brain FC is a foundational step in exploring EC. This study proposed a functionally guided EC (FGEC) method based on reinforcement learning (FGECRL) to enhance the precision of identifying EC between distinct brain regions. An actor-critic framework with an encoder-decoder model was adopted as the actor network. The encoder utilizes a transformer model; the decoder employs a bidirectional long short-term memory network with attention. An FGEC network was constructed for the enrolled participants per fMRI scan, including 65 patients with tinnitus and 28 control participants healthy at the enrollment time. After 6 months of sound therapy for tinnitus and prospective follow-up, fMRI data were acquired again and retrospectively categorized into an effective group (EG) and an ineffective group (IG) according to the treatment effect. Compared with FC and EC, the FGECRL method demonstrated better accuracy in discriminating between different groups, highlighting the advantage of FGECRL in identifying brain network features. For the FGEC network of the EG and IG per state (before and after treatment) and healthy controls, effective therapy is characterized by a similar pattern of FGEC network between patients with tinnitus after treatment and healthy controls. Deactivated information output in the motor network, somatosensory network, and medioventral occipital cortex may biologically indicate effective treatment. The maintenance of decreased EC in the primary auditory cortex may represent a failure of sound therapy, further supporting the Bayesian inference theory for tinnitus perception. The FGEC network can provide direct evidence for the mechanism of sound therapy in patients with tinnitus with distinct outcomes.


Assuntos
Mapeamento Encefálico , Zumbido , Humanos , Mapeamento Encefálico/métodos , Estudos Retrospectivos , Zumbido/terapia , Teorema de Bayes , Estudos Prospectivos , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
12.
J Clin Nurs ; 33(7): 2609-2618, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38108248

RESUMO

AIM: To analyse the risk factors and incidence of falls in geriatric outpatients in a university hospital ward in Hangzhou, China. METHODS: From May 2020 to August 2022, 1712 geriatric outpatients in a university hospital ward in Hangzhou, China, were screened using a socio-demographic questionnaire (e.g. gender, age, living arrangement, etc.) and assessment scales. The correlation between each factor and falls was preliminarily analysed by chi-squared tests. Finally, binary logistic regression analysis was conducted to further analyse the risk factors of falls. The STROBE checklist was used in reporting this study. RESULTS: Of the 1712 geriatric outpatients recruited, 1626 participants (60-79 and ≥ 80 years old) with complete questionnaire and assessment data were included. The occurrence of falls for those in the 60-79 age group was 8.4%, and for those in the ≥80 age group it was 13.4%. Age (p = .007), use of a walking assistance device (p < .001), the Stay Independent Brochure Questionnaire (SIB) (OR = 7.751, 95% CI = 5.089-11.806, p < .001), living arrangement (p = .004), timed up and go test (TUGT) (p = .007) and three diseases or above (OR = 2.496, 95% CI = 1.358-11.4.586, p = .003) reached statistical significance. CONCLUSIONS: Older people have a high incidence of falls. In this study, age, disease history, SIB scores (≥4 points), living arrangement, TUGT and walking assistance device increased the probability of falls in older Chinese adults. Personalised interventions should be carried out according to the specific situation of older people to effectively reduce their incidence of falls and improve their quality of life. RELEVANCE TO CLINICAL PRACTICE: The basic characteristics and fall risk factors of the older can help nurses identify fall risk, and early intervention by caregivers can reduce fall-related injuries, which has practical significance for promoting healthy aging. PATIENT OR PUBLIC CONTRIBUTION: The subjects of this study were older patients ≥60 years old, and the demographic characteristics and fall-related information of patients were obtained by questionnaire. The team worked closely with a team of experts in the field of health care. Some researchers collect data and rewrite them, while other researchers analyse the information and write a paper. All authors read and approved the final manuscript.


Assuntos
Acidentes por Quedas , Humanos , Acidentes por Quedas/estatística & dados numéricos , Acidentes por Quedas/prevenção & controle , Idoso , Estudos Transversais , Masculino , China/epidemiologia , Feminino , Fatores de Risco , Idoso de 80 Anos ou mais , Inquéritos e Questionários , Pessoa de Meia-Idade , Incidência , Avaliação Geriátrica/métodos , População do Leste Asiático
14.
Cerebellum ; 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993636

RESUMO

Ataxia-ocular apraxia 2 (AOA2) is a rare neurodegenerative autosomal recessive disorder with no effective treatment. In this study, we present the case of a patient diagnosed with AOA2, who experienced walking instability and uncoordinated movement. The patient underwent transcranial alternating current stimulation (tACS) treatment for 4 weeks with follow-up after 1 month. The effectiveness of the treatment was evaluated using the International Cooperative Ataxia Rating Scale (ICARS), the Scale for the Assessment and Rating of Ataxia (SARA), the 9-Hole Peg Test (9HPT), and functional near-infrared spectroscopy (fNIRS). Following treatment, the patient's ataxia symptoms showed significant improvement and continued to be alleviated during the follow-up period, suggesting a lasting effect of tACS treatment. Our findings from this case study provide compelling evidence for the potential of tACS as a treatment option for AOA2.

15.
Brain Commun ; 5(5): fcad261, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37869577

RESUMO

We determined the structural and functional alterations in the insula and its subregions in patients with idiopathic tinnitus in order to identify the neural changes involved in the progression from recent onset to chronic tinnitus. We recruited 24 recent-onset tinnitus patients, 32 chronic tinnitus patients and 36 healthy controls. We measured the grey matter volume and fractional amplitude of low-frequency fluctuation of the insula and its subregions and the functional connectivity within the insula and between the insula and the rest of the brain. Relationships between MRI and clinical characteristics were estimated using partial correlation analysis. Both recent-onset and chronic tinnitus patients showed decreased fractional amplitude of low-frequency fluctuation in the insula and its subregions, but only chronic tinnitus patients showed bilateral grey matter atrophy in the ventral anterior insula. Abnormal functional connectivity was detected in recent-onset and chronic tinnitus patients relative to the healthy controls, but functional connectivity differences between recent-onset and chronic tinnitus patients were found in only the auditory-related cortex, frontal cortex and limbic system. Functional alterations (fractional amplitude of low-frequency fluctuation and functional connectivity of the left ventral anterior insula), but not structural changes, were correlated with clinical severity. Bilateral grey matter atrophy in the ventral anterior insula decreased regional activities in the left ventral anterior insula and left posterior insula, and abnormal functional connectivity of the insula subregions with auditory and non-auditory areas were implicated in the progression from recent onset to chronic tinnitus. This suggests that tinnitus generation and development occur in a dynamic manner and involve aberrant multi-structural and functional (regional brain activity and abnormal functional connectivity) reorganization of the insula.

16.
Med Sci Monit ; 29: e941486, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37661601

RESUMO

BACKGROUND Inspiratory muscle training (IMT) aims to train inspiratory muscles based mainly on the diaphragm by applying a load resistance during the inspiratory process. Many papers related to IMT have been published in various journals; however, no articles objectively and directly present the development trends and research hotspots of IMT. Therefore, this study used CiteSpace to visually analyze recent IMT-related publications to provide valuable information for future IMT-related studies. MATERIAL AND METHODS CiteSpace was applied to analyze the IMT-related publications by countries, institutions, journals, authors, references, and keywords. RESULTS We included 504 papers. The number of IMT-related publications trended upward between 2009 and 2022. Leuven had the highest number of publications by an institution. The American Journal of Respiratory and Critical Care Medicine was the most frequently co-cited journal. Half of the top 10 references cited were from Journal Citation Reports (JCR) Q1 and half were about the application of IMT in chronic obstructive pulmonary disorder. Gosselink was the author with the highest number of publications and Aldrich was the author with the highest co-citation frequency. The preponderance of studies on the surgical population and postoperative pulmonary complications reflects potential application of IMT in enhanced recovery after surgery. CONCLUSIONS This study provides scholars with important information related to IMT research. It analyzes IMT research trends and status, which can help researchers identify primary topics in the field and find ways to explore new research directions to promote the application of IMT in clinical practice and the cooperation of IMT-related disciplines.


Assuntos
Diafragma , Instalações de Saúde , Humanos , Modalidades de Fisioterapia , Complicações Pós-Operatórias , Período Pós-Operatório
17.
Polymers (Basel) ; 15(14)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37514508

RESUMO

Structural damping composites exhibit considerable potential in aerospace and other fields due to their excellent damping and vibration reduction performance, as well as their structural carrying capacity. However, conventional structural damping composite materials generally do not combine excellent mechanical and damping properties at the same time, which makes it difficult for them to meet the practical demand in engineering. In this paper, polyetherimide (PEI) non-woven fabric interlayer materials loaded with quantified polydopamine (PDA) and carboxylated multi-walled carbon nanotubes (MWCNTs-COOH) were used to prepare carbon fiber-reinforced bismaleimide composites through the co-curing process. The mechanical and damping properties of the composites were systematically studied. The results demonstrate that PEI non-woven fabric interlayers loaded with PDA and MWCNTs-COOH can synchronously improve the mechanical and damping properties of the co-cured composites. The incorporation of carbon nanotubes and polydopamine during the co-curing process synergistically improves the flexural strength, flexural modulus, interlaminar shear strength, and impact fracture toughness of the composites. Most importantly, damping properties show an increase of 45.0% in the loss factor of the co-cured composites. Moreover, the reinforcement mechanism was investigated using the optical microscopy and scanning electron microscopy, which indicated that the PEI interlayers loaded with carbon nanotubes and polydopamine form a rich resin area between the layers of the composites.

18.
CNS Neurosci Ther ; 29(12): 4070-4081, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37392024

RESUMO

AIMS: This study systematically investigated structural and functional alterations in the thalamus and its subregions using multimodal magnetic resonance imaging (MRI) and examined its clinical relevance in tinnitus patients with different outcomes after sound therapy (narrowband noise). METHODS: In total, 60 patients with persistent tinnitus and 57 healthy controls (HCs) were recruited. Based on treatment efficacy, 28 patients were categorized into the effective group and 32 into the ineffective group. Five MRI measurements of the thalamus and its seven subregions, including gray matter volume, fractional anisotropy, fractional amplitude of low-frequency fluctuation, and functional connectivity (FC), were obtained for each participant and compared between the groups. RESULTS: Patients in both the groups exhibited widespread functional and diffusion abnormalities in the whole thalamus and several subregions, with more obvious changes observed in the effective group. All tinnitus patients had abnormal FC compared with the HCs; FC differences between the two patient groups were only observed in the striatal network, auditory-related cortex, and the core area of the limbic system. We combined the multimodal quantitative thalamic alterations and used it as an imaging indicator to evaluate prognosis before sound therapy and achieved a sensitivity of 71.9% and a specificity of 85.7%. CONCLUSION: Similar patterns of thalamic alterations were identified in tinnitus patients with different outcomes, with more obvious changes observed in the effective group. Our findings support the tinnitus generation hypothesis of frontostriatal gating system dysfunction. A combination of multimodal quantitative thalamic properties may be used as indicators to predict tinnitus prognosis before sound therapy.


Assuntos
Zumbido , Humanos , Zumbido/diagnóstico por imagem , Zumbido/terapia , Zumbido/patologia , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Sistema Límbico/patologia , Tálamo/diagnóstico por imagem
19.
J Zhejiang Univ Sci B ; 24(6): 539-543, 2023 Jun 15.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37309045

RESUMO

Epstein-Barr virus (EBV), a double-stranded DNA virus with an envelope, is a ubiquitous pathogen that is prevalent in humans, although most people who contract it do not develop symptoms (Kerr, 2019). While the primary cells EBV attacks are epithelial cells and B lymphocytes, its target range expands to a variety of cell types in immunodeficient hosts. Serological change occurs in 90% of infected patients. Therefore, immunoglobulin M (IgM) and IgG, serologically reactive to viral capsid antigens, are reliable biomarkers for the detection of acute and chronic EBV infections (Cohen, 2000). Symptoms of EBV infection vary according to age and immune status. Young patients with primary infection may present with infectious mononucleosis; there is a typical triad of symptoms including fever, angina, and lymphadenectasis (Houen and Trier, 2021). In immunocompromised patients, response after EBV infection may be atypical, with unexplained fever. The nucleic acid of EBV can be detected to confirm whether high-risk patients are infected (Smets et al., 2000). EBV is also associated with the occurrence of certain tumors (such as lymphoma and nasopharyngeal carcinoma) because it transforms host cells (Shannon-Lowe et al., 2017; Tsao et al., 2017).


Assuntos
Infecções por Vírus Epstein-Barr , Viroses , Humanos , Traqueia , Herpesvirus Humano 4 , Febre , Granuloma
20.
Exp Ther Med ; 25(6): 241, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37153898

RESUMO

Chronic pain is the primary symptom of osteoarthritis affecting a patient's quality of life. Neuroinflammation and oxidative stress in the spinal cord contribute to arthritic pain and represent ideal targets for pain management. In the present study, a model of arthritis was established by intra-articular injection of complete Freund's adjuvant (CFA) into the left knee joint in mice. After CFA inducement, knee width and pain hypersensitivity in the mice were increased, motor disability was impaired, spinal inflammatory reaction was induced, spinal astrocytes were activated, antioxidant responses were decreased, and glycogen synthase kinase 3ß (GSK-3ß) activity was inhibited. To explore the potential therapeutic options for arthritic pain, lycorine was intraperitoneally injected for 3 days in the CFA mice. Lycorine treatment significantly reduced mechanical pain sensitivity, suppressed spontaneous pain, and recovered motor coordination in the CFA-induced mice. Additionally, in the spinal cord, lycorine treatment decreased the inflammatory score, reduced NOD-like receptor protein 3 inflammasome (NLRP3) activity and IL-1ß expression, suppressed astrocytic activation, downregulated NF-κB levels, increased nuclear factor erythroid 2-related factor 2 expression and superoxide dismutase activity. Furthermore, lycorine was shown to bind to GSK-3ß through three electrovalent bonds, to inhibit GSK-3ß activity. In summary, lycorine treatment inhibited GSK-3ß activity, suppressed NLRP3 inflammasome activation, increased the antioxidant response, reduced spinal inflammation, and relieved arthritic pain.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...