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1.
ACS Appl Mater Interfaces ; 16(19): 25304-25316, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38654450

RESUMO

Poly(vinyl alcohol) (PVA) hydrogels are water-rich, three-dimensional (3D) network materials that are similar to the tissue structure of living organisms. This feature gives hydrogels a wide range of potential applications, including drug delivery systems, articular cartilage regeneration, and tissue engineering. Due to the large amount of water contained in hydrogels, achieving hydrogels with comprehensive properties remains a major challenge, especially for isotropic hydrogels. This study innovatively prepares a multiscale-reinforced PVA hydrogel from molecular-level coupling to nanoscale enhancement by chemically cross-linking poly(vinylpyrrolidone) (PVP) and in situ assembled aromatic polyamide nanofibers (ANFs). The optimized ANFs-PVA-PVP (APP) hydrogels have a tensile strength of ≈9.7 MPa, an elongation at break of ≈585%, a toughness of ≈31.84 MJ/m3, a compressive strength of ≈10.6 MPa, and a high-water content of ≈80%. It is excellent among all reported PVA hydrogels and even comparable to some anisotropic hydrogels. System characterizations show that those performances are attributed to the particular multiscale load-bearing structure and multiple interactions between ANFs and PVA. Moreover, APP hydrogels exhibit excellent biocompatibility and a low friction coefficient (≈0.4). These valuable performances pave the way for broad potential in many advanced applications such as biological tissue replacement, flexible wearable devices, electronic skin, and in vivo sensors.


Assuntos
Materiais Biocompatíveis , Hidrogéis , Nanofibras , Álcool de Polivinil , Povidona , Nanofibras/química , Álcool de Polivinil/química , Hidrogéis/química , Povidona/química , Materiais Biocompatíveis/química , Animais , Camundongos , Nylons/química , Resistência à Tração , Teste de Materiais , Força Compressiva
2.
Medicine (Baltimore) ; 103(7): e37090, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363909

RESUMO

The aim of this study is to elucidate the prevalence of depression and examine the contributing factors to depression among adolescents in Xinjiang, China. A stratified cluster sampling methodology was employed in this study, with the sample size determined through consideration of prior studies on adolescent depression. Employing this approach, 6 schools were chosen from each prefecture-level city, designated as urban areas, and 3 schools were selected from each county. Subsequently, individual classes were treated as units, and a minimum of 80 students from each grade were surveyed within the entire class. The investigation of adolescents involved the administration of a questionnaire assessing the factors influencing depression, along with the Center for Epidemiologic Studies Depression Scale (CES-D). Multivariate linear regression was used to analyze the influencing factors of depression. The occurrence rates of depression were 12.17%, 13.05%, 12.32%, and 9.29% in junior middle school, senior middle school, vocational high school, and college, respectively. The corresponding CES-D scores were 10.54 ±â€…8.26, 11.20 ±â€…8.37, 12.17 ±â€…6.94, and 11.33 ±â€…6.28. Significant associations with the CES-D score were observed for gender, smoking, alcohol consumption, and spending more than 4 hours online daily across the educational levels mentioned. The risk of experiencing depressive symptoms was elevated among female junior and senior high school students who spent more than 4 hours daily on the internet, engaged in cigarette smoking, and consumed alcohol. The findings underscore the significance of targeting high-risk groups, particularly through home-school collaborations, to mitigate excessive internet use and consequently reduce the likelihood of depressive symptoms in students.


Assuntos
Depressão , Humanos , Adolescente , Feminino , Estudos Transversais , Prevalência , Depressão/epidemiologia , Depressão/diagnóstico , Inquéritos e Questionários , China/epidemiologia
3.
Foods ; 12(11)2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37297418

RESUMO

Dried green pepper and first-grade extracted soybean oil were selected as raw materials to study the effect of the Maillard reaction and cold-pressed compound on the quality of Zanthoxylum seasoning oil and its aroma-enhancing effect. The results showed that the optimal technology was as follows: the ratio of material to liquid was 1:5, the heating temperature was 110 °C, the reaction time was 25 or 30 min, and the addition of reducing sugar was 2%. The optimum ratio of fragrant Zanthoxylum seasoning oil was 1:7 for cold pressing oil and hot dipping oil. Compared with Zanthoxylum seasoning oil, it is based on the Maillard reaction and had a more intense and persistent aroma. The taste of fragrant Zanthoxylum seasoning oil was the best of the three blended oils. The possible types of volatile flavor compounds in the three kinds of Zanthoxylum seasoning oils detected by Heracles II ultra-fast gas phase electronic nose were, respectively, 16, 19, and 15. Among the three kinds of Zanthoxylum seasoning oils, the content of limonene, linalool, Eucalyptol, n-pentane α-Pinene, myrcene, and phellandrene was more abundant, which indicated that olefins and alcohols contributed more to the overall flavor of the three kinds of Zanthoxylum seasoning oils.

4.
Microbiol Spectr ; 11(3): e0307922, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37014208

RESUMO

Bax-interacting factor-1 (Bif-1) is a multifunctional protein involved in apoptosis, autophagy, and mitochondrial morphology. However, the associations between Bif-1 and viruses are poorly understood. As discrete Bif-1 isoforms are selectively expressed and exert corresponding effects, we evaluated the effects of neuron-specific/ubiquitous Bif-1 isoforms on rabies virus (RABV) proliferation. First, infection with the RABV CVS-11 strain significantly altered Bif-1 expression in mouse neuroblastoma (N2a) cells, and Bif-1 knockdown in turn promoted RABV replication. Overexpression of neuron-specific Bif-1 isoforms (Bif-1b/c/e) suppressed RABV replication. Moreover, our study showed that Bif-1c colocalized with LC3 and partially alleviated the incomplete autophagic flux induced by RABV. Taken together, our data reveal that neuron-specific Bif-1 isoforms impair the RABV replication process by abolishing autophagosome accumulation and blocking autophagic flux induced by the RABV CVS-11 strain in N2a cells. IMPORTANCE Autophagy can be triggered by viral infection and replication. Autophagosomes are generated and affect RABV replication, which differs by viral strain and infected cell type. Bax-interacting factor-1 (Bif-1) mainly has a proapoptotic function but is also involved in autophagosome formation. However, the association between Bif-1-involved autophagy and RABV infection remains unclear. In this study, our data reveal that a neuron-specific Bif-1 isoform, Bif-1c, impaired viral replication by unchoking autophagosome accumulation induced by RABV in N2a cells to a certain extent. Our study reveals for the first time that Bif-1 is involved in modulating autophagic flux and plays a crucial role in RABV replication, establishing Bif-1 as a potential therapeutic target for rabies.


Assuntos
Vírus da Raiva , Raiva , Animais , Camundongos , Vírus da Raiva/metabolismo , Proteína X Associada a bcl-2/metabolismo , Proteína X Associada a bcl-2/farmacologia , Autofagia , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/farmacologia , Proliferação de Células
5.
Quant Imaging Med Surg ; 12(2): 1608-1631, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35111652

RESUMO

Optical ultrasound sensors have been increasingly employed in biomedical diagnosis and photoacoustic imaging (PAI) due to high sensitivity and resolution. PAI could visualize the distribution of ultrasound excited by laser pulses in biological tissues. The information of tissues is detected by ultrasound sensors in order to reconstruct structural images. However, traditional ultrasound transducers are made of piezoelectric films that lose sensitivity quadratically with the size reduction. In addition, the influence of electromagnetic interference limits further applications of traditional ultrasound transducers. Therefore, optical ultrasound sensors are developed to overcome these shortcomings. In this review, optical ultrasound sensors are classified into resonant and non-resonant ones in view of physical principles. The principles and basic parameters of sensors are introduced in detail. Moreover, the state of the art of optical ultrasound sensors and applications in PAI are also presented. Furthermore, the merits and drawbacks of sensors based on resonance and non-resonance are discussed in perspectives. We believe this review could provide researchers with a better understanding of the current status of optical ultrasound sensors and biomedical applications.

6.
Mediators Inflamm ; 2020: 7605160, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32377164

RESUMO

Alzheimer's disease (AD) is a common neurodegenerative disease. Aß plays an important role in the pathogenesis of AD. Sodium butyrate (NaB) is a short-chain fatty acid salt that exerts neuroprotective effects such as anti-inflammatory, antioxidant, antiapoptotic, and cognitive improvement in central nervous system diseases. The aim of this study is to research the protective effects of NaB on neurons against Aß toxicity and to uncover the underlying mechanisms. The results showed that 2 mM NaB had a significant improvement effect on Aß-induced N2a cell injury, by increasing cell viability and reducing ROS to reduce injury. In addition, by acting on the GPR109A receptor, NaB regulates the expression of AD-related genes such as APP, NEP, and BDNF. Therefore, NaB protects N2a cells from Aß-induced cell damage through activating GPR109A, which provides an innovative idea for the treatment of AD.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Ácido Butírico/farmacologia , Fármacos Neuroprotetores/farmacologia , Animais , Fator Neurotrófico Derivado do Encéfalo/análise , Sobrevivência Celular/efeitos dos fármacos , Transporte de Elétrons/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , Receptores Acoplados a Proteínas G/fisiologia , Células Tumorais Cultivadas
7.
Free Radic Biol Med ; 152: 728-742, 2020 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-31972340

RESUMO

Oxidative stress consistently affects lactation length and quality in dairy cows. Oxidative stress in the mammary gland of high-yielding dairy cows is a serious problem. Therefore, we studied the role of butyrate in dairy cow oxidative stress and further elucidated the mechanism of the antioxidative action of mammary epithelial cells in dairy cows. Oxidative stress and activated GPR109A were present in high-yielding dairy cows. Then, bovine mammary epithelial cells (BMECs) were isolated, and oxidative stress-related protein expression was measured, confirming that sodium butyrate (NaB) exerted antioxidant effects through GPR109A, NRF2 and H3K9/14 acetylation. To further study the antioxidative mechanism of butyrate in dairy cows, we also confirmed that butyrate promoted NRF2 nuclear accumulation and H3K9/14 acetylation through the AMPK signaling pathway by western blotting. Additionally, we preliminarily clarified the interaction between NRF2 and H3K9/14 acetylation by Co-IP and ChIP. Butyrate activated the AMPK signaling pathway through GPR109A to promote NRF2 nuclear accumulation and H3K9/14 acetylation, subsequently exerting antioxidant effects through the synergistic functions of these two processes. Then, we studied the effect of butyrate on oxidative stress in dairy cows in vivo, and the results were consistent with those in vitro. Therefore, butyrate played an antioxidant and antiapoptotic role through the GPR109A/AMPK/NRF2 signaling pathway, while H3K9/14 acetylation could promote NRF2 transcription and enhance the antioxidant capacity of BMECs.


Assuntos
Células Epiteliais , Fator 2 Relacionado a NF-E2 , Acetilação , Animais , Ácido Butírico/farmacologia , Bovinos , Células Epiteliais/metabolismo , Feminino , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo
8.
Front Microbiol ; 10: 2419, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31708894

RESUMO

Bacterial symbionts are omnipresent in insects, particularly aphids, and often exert important effects on the host ecology; however, examples of symbionts that mediate herbivore-plant interactions remain limited. Here, three clones with identical genetic backgrounds were established: a Hamiltonella defensa-free clone, H. defensa-infected clone and H. defensa-cured clone. H. defensa infection was found to increase the fitness of Sitobion miscanthi by increasing the total number of offspring and decreasing the age of first reproduction. Furthermore, gene expression studies and phytohormone measurement showed that feeding by the Hamiltonella-infected clone suppressed the salicylic acid (SA)- and jasmonic acid (JA)-related defense pathways and SA/JA accumulation in wheat plants relative to feeding by the other two clones. Additionally, after feeding by the Hamiltonella-infected clone, the activity levels of the defense-related enzymes polyphenol oxidase (PPO) and peroxidase (POD) in wheat plants were significantly decreased compared with the levels observed after feeding by the other two clones. Taken together, these data reveal for the first time the potential role of H. defensa of S. miscanthi in mediating the anti-plant defense responses of aphids.

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