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1.
Nat Commun ; 15(1): 3124, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600164

RESUMO

Crop wild relatives offer natural variations of disease resistance for crop improvement. Here, we report the isolation of broad-spectrum powdery mildew resistance gene Pm36, originated from wild emmer wheat, that encodes a tandem kinase with a transmembrane domain (WTK7-TM) through the combination of map-based cloning, PacBio SMRT long-read genome sequencing, mutagenesis, and transformation. Mutagenesis assay reveals that the two kinase domains and the transmembrane domain of WTK7-TM are critical for the powdery mildew resistance function. Consistently, in vitro phosphorylation assay shows that two kinase domains are indispensable for the kinase activity of WTK7-TM. Haplotype analysis uncovers that Pm36 is an orphan gene only present in a few wild emmer wheat, indicating its single ancient origin and potential contribution to the current wheat gene pool. Overall, our findings not only provide a powdery mildew resistance gene with great potential in wheat breeding but also sheds light into the mechanism underlying broad-spectrum resistance.


Assuntos
Ascomicetos , Triticum , Triticum/genética , Melhoramento Vegetal , Genes de Plantas , Ascomicetos/genética , Mapeamento Cromossômico , Resistência à Doença/genética , Doenças das Plantas/genética
2.
Langmuir ; 40(15): 7982-7991, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38569012

RESUMO

In this study, we explored an innovative application of heat-assisted solution electrospinning, a technique that significantly advances the control of phase separation in polystyrene (PS) fibers. Our experimental approach involved the use of direct heating and a convection air sheath applied through a coaxial needle, focusing on solvents with varying vapor pressures. This method enabled a detailed investigation into how solvent evaporation rates affect the morphology of the electrospun fibers. SEM and AFM measurements revealed that the application of direct heating and a heated air sheath offered precise control over the fiber morphology, significantly influencing both the surface and internal structure of the fibers. Additionally, we observed notable changes in fiber diameter, indicating that heat-assisted electrospinning can be effectively utilized to tailor fiber dimensions according to specific application requirements. Moreover, our research demonstrated the critical role of solvent properties, particularly vapor pressure, in determining the final characteristics of the electrospun fibers. By comparing fibers produced with different solvents, we gained insights into the complex interplay between solvent dynamics and heat application in fiber formation. The implications of these findings are far-reaching, offering new possibilities for the fabrication of nanofibers with customized properties. Furthermore, this could have profound impacts on various applications, from biomedical to environmental, where specific fiber characteristics are crucial. This study not only contributes to the understanding of phase separation in electrospinning but also opens avenues for further research on the optimization of fiber properties for diverse industrial and scientific applications.

3.
Clin Med Insights Oncol ; 18: 11795549241236896, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38645894

RESUMO

By modifying immune cells, immunotherapy can activate immune response to establish long-term immune memory and prevent tumor recurrence. However, their effectiveness is largely constricted by the poor immunogenicity, immune escape, and immune tolerance of the tumor. This is related to the characteristics of the tumor itself, such as genome instability and mutation. The combination of various nanocarriers with tumor immunotherapy is beneficial for overcoming the shortcomings of traditional immunotherapy. Nanocarriers coated by cell membranes can extend blood circulation time, improve ability to evade immune clearance, and enhance targeting, thus significantly enhancing the efficacy of immunotherapy and showing great potential in tumor immunotherapy. This article reviews the application research progress of different types of cell membrane-modified nanocarriers in tumor immunotherapy, immunotherapy combination therapy, and tumor vaccines, and provides prospects for future research.

4.
Sci Rep ; 14(1): 9182, 2024 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649422

RESUMO

In order to obtain high yield pomelo peel pectin with better physicochemical properties, four pectin extraction methods, including hot acid extraction (HAE), microwave-assisted extraction (MAE), ultrasound-assisted extraction, and enzymatic assisted extraction (EAE) were compared. MAE led to the highest pectin yield (20.43%), and the lowest pectin recovery was found for EAE (11.94%). The physicochemical properties of pomelo peel pectin obtained by different methods were also significantly different. Pectin samples obtained by MAE had the highest methoxyl content (8.35%), galacturonic acid content (71.36%), and showed a higher apparent viscosity, thermal and emulsion stability. The pectin extracted by EAE showed the highest total phenolic content (12.86%) and lowest particle size (843.69 nm), showing higher DPPH and ABTS scavenging activities than other extract methods. The pectin extracted by HAE had the highest particle size (966.12 nm) and degree of esterification (55.67%). However, Fourier-transform infrared spectroscopy showed that no significant difference occurred among the different methods in the chemical structure of the extracted pectin. This study provides a theoretical basis for the industrial production of pomelo peel pectin.


Assuntos
Citrus , Ácidos Hexurônicos , Pectinas , Pectinas/química , Pectinas/isolamento & purificação , Citrus/química , Viscosidade , Tamanho da Partícula , Micro-Ondas , Espectroscopia de Infravermelho com Transformada de Fourier , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Fracionamento Químico/métodos , Fenômenos Químicos , Frutas/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Fenóis/análise , Fenóis/química , Fenóis/isolamento & purificação , Esterificação
5.
World J Hepatol ; 16(3): 465-476, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38577526

RESUMO

BACKGROUND: Although hepatitis B virus infection is the leading cause of chronic liver injury globally, nonalcoholic fatty liver disease (NAFLD) is gradually gaining attention as another major chronic liver disease. The number of patients having chronic hepatitis B (CHB) with concomitant hepatic steatosis has increased. AIM: To analyze the effect of NAFLD on the response to antiviral treatment in patients with CHB. METHODS: Relevant English studies were systematically searched across PubMed, EMBASE, Web of Science, and Cochrane Library until October 2023. Studies in which the treatment outcomes were compared between patients with CHB only and those with CHB and hepatic steatosis were included. RESULTS: Of the 2502 retrieved studies, 11 articles were finally included. Biochemical response until 48 wk (OR = 0.87, 95%CI: 0.50-1.53, P = 0.000) and 96 wk (OR = 0.35, 95%CI: 0.24-0.53, P = 0.24) and virological response until 96 wk (OR = 0.80, 95%CI: 0.43-1.49, P = 0.097) were lower in patients with hepatic steatosis than in patients with CHB alone. CONCLUSION: Hepatic steatosis lowers the biochemical response to antiviral treatment in patients with CHB.

6.
Nat Genet ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658793

RESUMO

Large-scale genomic variations are fundamental resources for crop genetics and breeding. Here we sequenced 1,904 genomes of broomcorn millet to an average of 40× sequencing depth and constructed a comprehensive variation map of weedy and cultivated accessions. Being one of the oldest cultivated crops, broomcorn millet has extremely low nucleotide diversity and remarkably rapid decay of linkage disequilibrium. Genome-wide association studies identified 186 loci for 12 agronomic traits. Many causative candidate genes, such as PmGW8 for grain size and PmLG1 for panicle shape, showed strong selection signatures during domestication. Weedy accessions contained many beneficial variations for the grain traits that are largely lost in cultivated accessions. Weedy and cultivated broomcorn millet have adopted different loci controlling flowering time for regional adaptation in parallel. Our study uncovers the unique population genomic features of broomcorn millet and provides an agronomically important resource for cereal crops.

7.
Microbiol Spectr ; : e0197923, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647315

RESUMO

Numerous studies have supported that nonalcoholic fatty liver disease (NAFLD) is highly associated with gut microbiota dysbiosis. Ling-Gui-Zhu-Gan decoction (LG) has been clinically used to treat NAFLD, but the underlying mechanism remains unknown. This study investigated the therapeutic effect and mechanisms of LG in mice with NAFLD induced by a high-fat diet (HD). An HD-induced NAFLD mice model was established to evaluate the efficacy of LG followed by biochemical and histopathological analysis. Metagenomics, metabolomics, and transcriptomics were used to explore the structure and metabolism of the gut microbiota. LG significantly improved hepatic function and decreased lipid droplet accumulation in HD-induced NAFLD mice. LG reversed the structure of the gut microbiota that is damaged by HD and improved intestinal barrier function. Meanwhile, the LG group showed a lower total blood bile acids (BAs) concentration, a shifted BAs composition, and a higher fecal short-chain fatty acids (SCFAs) concentration. Furthermore, LG could regulate the hepatic expression of genes associated with the primary BAs biosynthesis pathway and peroxisome proliferator-activated receptor (PPAR) signaling pathway. Our study suggested that LG could ameliorate NAFLD by altering the structure and metabolism of gut microbiota, while BAs and SCFAs are considered possible mediating substances. IMPORTANCE: Until now, there has still been no study on the gut microbiota and metabolomics of Ling-Gui-Zhu-Gan decoction (LG) in nonalcoholic fatty liver disease (NAFLD) mouse models. Our study is the first to report on the reshaping of the structure and metabolism of the gut microbiota by LG, as well as explore the potential mechanism underlying the improvement of NAFLD. Specifically, our study demonstrates the potential of gut microbial-derived short-chain fatty acids (SCFAs) and blood bile acids (BAs) as mediators of LG therapy for NAFLD in animal models. Based on the results of transcriptomics, we further verified that LG attenuates NAFLD by restoring the metabolic disorder of BAs via the up-regulation of Fgf15/FXR in the ileum and down-regulation of CYP7A1/FXR in the liver. LG also reduces lipogenesis in NAFLD mice by mediating the peroxisome proliferator-activated receptor (PPAR) signaling pathway, which then contributes to reducing hepatic inflammation and improving intestinal barrier function to treat NAFLD.

8.
Heliyon ; 10(7): e29347, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38617920

RESUMO

Background: Seldom have the associations of preoperative CEA (p-CEA) and recurrent CEA (r-CEA) levels as well as changes in p-CEA and r-CEA with survival in patients with stage I-III colorectal cancer (CRC) who have experienced metastatic relapse, been thoroughly examined. Methods: 241 consecutive patients with stage I-III CRC who experienced metastatic relapse at Fudan University Shanghai Cancer Center (FUSCC) between January 2008 and January 2016 were investigated. The influence of p-CEA, r-CEA and CEA alteration on the overall survival (OS) and relapse-to-death survival (RDS) was evaluated. The restricted cubic spline regression model was employed to explore the optimal cut-off value of CEA. Results: All 241 patients were categorized into four groups built on their CEA alteration patterns as follows: A, patients presenting elevated p-CEA levels but normal r-CEA levels (P-N); B, patients displaying normal levels of both p-CEA and r-CEA (N-N); C, patients exhibiting elevated levels of both p-CEA and r-CEA (P-P); D, patients with normal p-CEA levels but elevated r-CEA levels (N-P). The correlation between p-CEA and OS (P = 0.3266) and RDS (P = 0.2263) was insignificant. However, r-CEA exhibited a significant association with both OS (P = 0.0005) and RDS (P = 0.0002). Group A demonstrated the longest OS and RDS, whereas group D exhibited the poorest OS and RDS outcomes. For both OS and RDS, the CEA alteration groups served as an independent prognostic indicator. The optimal cut-off threshold for CEA was determined to be 5.1 ng/ml via the restricted cubic spline regression model. Conclusion: r-CEA has a stronger correlation with OS and RDS in individuals with stage I-III CRC who have experienced metastatic relapse.The change between p-CEA and r-CEA could further indicate post-relapse survival, thereby facilitating the assessment of mortality risk stratification in stage I-III CRC patients experiencing metastatic relapse.

9.
Tzu Chi Med J ; 36(2): 195-202, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38645789

RESUMO

Objective: Uremic pruritus (UP) is a prevalent and troublesome condition affecting individuals with end-stage renal failure, which results in intense pruritus, depression, as well as poor quality of sleep, significantly impacting their quality of life. According to previous studies, acupuncture and acupoint stimulation have been shown to provide additional benefits in treating UP in dialysis patients. In addition, using acupoints combination may yield superior effectiveness compared to utilizing a singular acupoint. To investigate the potential correlations between acupoint combinations, an association-rule analysis was employed. Materials and Methods: Apriori algorithms stand out as highly potent techniques for identifying associations in databases; this study utilized an association rule mining to examine the association rules of key acupoint groupings that could be employed for treating UP. Results: The analysis utilized information derived from the meta-analysis encompassing 40 randomized controlled trials that used acupuncture to treat UP. In total, 64 acupoints were analyzed, and 71 association rules were found. The following acupoint combinations: Auricular shenmen (TF4), Quchi (LI11), and Geshu (BL17); Auricular heart (Extra14), Sanyinjiao (SP6), and Auricular lung (CO14); and Auricular heart (Extra14), Xuehai (SP10), and Auricular lung (CO14) showed the strongest associations. Conclusion: Acupoints involving Auricular shenmen (TF4), Quchi (LI11), Geshu (BL17), Auricular heart (Extra14), Sanyinjiao (SP6), Auricular lung (CO14), and Xuehai (SP10) can be regarded as the core combination of acupuncture points for managing UP.

10.
Front Neurol ; 15: 1342788, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38595850

RESUMO

Background: Uremic pruritus (UP) is a common complication of chronic kidney disease that causes sleep disturbances and increases all-cause mortality. Currently, the first-line medications for UP exhibit inadequate pruritus control with adverse effects. Various acupuncture point stimulation treatments (APSTs) have been shown to be effective as adjuvant therapies in UP, and a network meta-analysis can offer relative efficacy estimates for treatments for which head-to-head studies have not been performed. Methods: We conducted a random-effects network meta-analysis on a consistency model to compare the different APSTs for UP. The primary outcomes were the mean visual analog scale (VAS) score and effectiveness rate (ER). Results: The network meta-analysis retrieved 27 randomized controlled trials involving 1969 patients. Compared with conventional treatment alone, combination treatment with acupuncture (mean difference, -2.63; 95% confidence interval, -3.71 to -1.55) was the most effective intervention in decreasing VAS scores, followed by acupoint injection and massage (mean difference, -2.04; 95% confidence interval, -3.96 to -0.12). In terms of the ER, conventional treatment with acupuncture and hemoperfusion (risk ratio, 14.87; 95% confidence interval, 2.18 to 101.53) was superior to other therapeutic combinations. Considering the VAS score and ER, combination treatment with acupoint injection and massage showed benefits in treating UP. Conclusion: Our network meta-analysis provided relative efficacy data for choosing the optimal adjuvant treatment for UP. Combined treatment with acupuncture was more effective than conventional treatment only and was the most promising intervention for treating UP.Systematic review registration: PROSPERO (CRD42023425739: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023425739).

11.
Small ; : e2308784, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38593360

RESUMO

Interconnect materials play the critical role of routing energy and information in integrated circuits. However, established bulk conductors, such as copper, perform poorly when scaled down beyond 10 nm, limiting the scalability of logic devices. Here, a multi-objective search is developed, combined with first-principles calculations, to rapidly screen over 15,000 materials and discover new interconnect candidates. This approach simultaneously optimizes the bulk electronic conductivity, surface scattering time, and chemical stability using physically motivated surrogate properties accessible from materials databases. Promising local interconnects are identified that have the potential to outperform ruthenium, the current state-of-the-art post-Cu material, and also semi-global interconnects with potentially large skin depths at the GHz operation frequency. The approach is validated on one of the identified candidates, CoPt, using both ab initio and experimental transport studies, showcasing its potential to supplant Ru and Cu for future local interconnects.

13.
Physiol Behav ; : 114534, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38583548

RESUMO

The aim of this study was to investigate the effects of acupressure bladder meridian (ABM) on anxiety in rats. Chronic stress was induced rats to establish rat anxiety model. Shuttle experiment and open field experiments of were used to measure behaviors. The levels of cytokines in serum and hippocampus of rats were detected. Brain neurotransmitters (dopamine, 5- hydroxy tryptamine, norepinephrine) were detected by Enzyme linked immunosorbent assay (ELISA) kits. Immunohistochemistry and western blotting were used to detect MAPK and BDNF signal pathway in hippocampus of rats. ABM significantly improve behaviors, decreased cytokine levels in serum and hippocampus. ABM restored the changes of neurotransmitters and significantly decreased protein expressions of MAPK signal pathway and increased protein expressions of BDNF signal pathway in hippocampus of rats. The results shown that ABM significantly improved anxiety via inhibition of MAPK signal pathway and increased BDNF signal pathway.

14.
Cancer Cell ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38579725

RESUMO

The tumor microenvironment (TME) in pancreatic ductal adenocarcinoma (PDAC) involves a significant accumulation of cancer-associated fibroblasts (CAFs) as part of the host response to tumor cells. The origins and functions of transcriptionally diverse CAF populations in PDAC remain poorly understood. Tumor cell-intrinsic genetic mutations and epigenetic dysregulation may reshape the TME; however, their impacts on CAF heterogeneity remain elusive. SETD2, a histone H3K36 trimethyl-transferase, functions as a tumor suppressor. Through single-cell RNA sequencing, we identify a lipid-laden CAF subpopulation marked by ABCA8a in Setd2-deficient pancreatic tumors. Our findings reveal that tumor-intrinsic SETD2 loss unleashes BMP2 signaling via ectopic gain of H3K27Ac, leading to CAFs differentiation toward lipid-rich phenotype. Lipid-laden CAFs then enhance tumor progression by providing lipids for mitochondrial oxidative phosphorylation via ABCA8a transporter. Together, our study links CAF heterogeneity to epigenetic dysregulation in tumor cells, highlighting a previously unappreciated metabolic interaction between CAFs and pancreatic tumor cells.

15.
Materials (Basel) ; 17(7)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38612099

RESUMO

Release of formaldehyde gas indoors is a serious threat to human health. The traditional adsorption method is not stable enough for formaldehyde removal. Photocatalytic degradation of formaldehyde is effective and rapid, but photocatalysts are generally expensive and not easy to recycle. In this paper, geopolymer microspheres were applied as matrix materials for photocatalysts loading to degrade formaldehyde. Geopolymer microspheres were prepared from red mud and granulated blast furnace slag as raw materials by alkali activation. When the red mud doping was 50%, the concentration of NaOH solution was 6 mol/L, and the additive amount was 30 mL, the prepared geopolymer microspheres possessed good morphological characteristics and a large specific surface area of 38.80 m2/g. With the loading of BiOX (X = Cl, Br, I) photocatalysts on the surface of geopolymer microspheres, 85.71% of formaldehyde gas were adsorbed within 60 min. The formaldehyde degradation rate of the geopolymer microspheres loaded with BiOI reached 87.46% within 180 min, which was 23.07% higher than that of the microspheres loaded with BiOBr, and 50.50% higher than that of the microspheres loaded with BiOCl. While ensuring the efficient degradation of formaldehyde, the BiOX (X = Cl, Br, I)-loaded geopolymer microspheres are easy to recycle and can save space. This work not only promotes the resource utilization of red mud and granulated blast furnace slag, but also provides a new idea on the formation of catalysts in the process of photocatalytic degradation of formaldehyde.

16.
Heliyon ; 10(4): e26700, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38434034

RESUMO

Objective: This study aimed to study whether modified Taohong Siwu decoction (MTHSWD) combined with human induced pluripotent stem cells-derived cardiomyocytes (iPS-CMs) transplantation can promote cardiac function in myocardial infarction (MI) nude mouse model and explore its possible mechanism. Methods: The MI mouse model was established by the ligation of left anterior descending coronary artery. After 4 weeks of gavage of MTHSWD combined with iPS-CMs transplantation, the changes in heart function of mice were examined by echocardiography. The histological changes were observed by Masson's trichrome staining. The survival and differentiation of transplanted cells were detected by double immunofluorescence staining of human nuclear antigen (HNA) and cardiac troponin T (cTnT). The number of c-kit-positive cells in the infarct area were evaluated by immunofluorescent staining. The levels of stromal cell-derived factor 1 (SDF-1), stem cell factor (SCF), vascular endothelial growth factor (VEGF) and basic fibroblast growth factor in infarcted myocardium tissues were detected by ELISA. Results: MTHSWD combined with iPS-CMs transplantation can improve the heart function of MI mice, reduce the infarct size and collagen deposition in infarct area. By immunofluorescence double-label detection of HNA and cTnT, it was found that MTHSWD combined with iPS-CMs transplantation can improve the survival and maturation of iPS-CMs. In addition, MTHSWD combined with iPS-CMs transplantation can activate more endogenous c-kit positive cardiac mesenchymal cells, and significantly increase the content of SDF-1, SCF and VEGF in myocardial tissues. Conclusions: The combination of MTHSWD with iPS-CMs transplantation promoted cardiac function of nude mice with MI by improving the survival and maturation of iPS-CMs in the infarct area, activating the endogenous c-kit positive cardiac mesenchymal cells, and increasing paracrine.

17.
Exp Ther Med ; 27(4): 138, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38476914

RESUMO

Dens invaginatus (DI) is a rare congenital dental malformation characterized by enamel or cementum folded into dentine. Such teeth are susceptible to caries, pulp infection or necrosis and periradicular lesion. The complex anatomy of this disease results in difficult treatment and a high rate of therapeutic failure. Therapeutic options, such as debriding and filling invagination, root canal treatment (RCT) and intentional replantation, vary according to the morphology and infection of the involved tooth. The present study reports five cases of DI with chronic apical periodontitis. The treatment strategies and procedures, including RCT, removing the invagination, intentional replantation and surgical treatment, are discussed according to the classification and the condition of pulp and periapical tissue. The study also reports the prognosis: All patients were followed up for ≥12 months and all teeth demonstrated periapical healing and clinical asymptomatic. In summary, appropriate treatment is based on accurate analysis of the anatomical variation in different types of DI and intentional replantation is a reliable and viable treatment to preserve the tooth.

18.
Adv Sci (Weinh) ; : e2306378, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38482749

RESUMO

Aspirin, also named acetylsalicylate, can directly acetylate the side-chain of lysine in protein, which leads to the possibility of unexplained drug effects. Here, the study used isotopic-labeling aspirin-d3 with mass spectrometry analysis to discover that aspirin directly acetylates 10 HDACs proteins, including SIRT1, the most studied NAD+ -dependent deacetylase. SIRT1 is also acetylated by aspirin in vitro. It is also identified that aspirin directly acetylates lysine 408 of SIRT1, which abolishes SIRT1 deacetylation activity by impairing the substrates binding affinity. Interestingly, the lysine 408 of SIRT1 can be acetylated by CBP acetyltransferase in cells without aspirin supplement. Aspirin can inhibit SIRT1 to increase the levels of acetylated p53 and promote p53-dependent apoptosis. Moreover, the knock-in mice of the acetylation-mimic mutant of SIRT1 show the decreased production of pro-inflammatory cytokines and maintain intestinal immune homeostasis. The study indicates the importance of the acetylated internal functional site of SIRT1 in maintaining intestinal immune homeostasis.

19.
J Youth Adolesc ; 53(6): 1428-1440, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38555341

RESUMO

Despite extensive research on the psychological impacts of digital technology, the nuanced dynamics between adolescent loneliness and problematic smartphone use, particularly across different educational levels and genders, remain underexplored. This study aims to fill this gap by employing a Random Intercept Cross-Lagged Panel Model to dissect the bidirectional relationship between loneliness and problematic smartphone use among adolescents, with a focus on the moderating roles of educational levels and gender. Engaging 3132 students from various educational institutions in China, the research conducted a three-wave longitudinal analysis across 2022-2023. The final number of participants included 1120 adolescents (53.5% female; age in 2022: M = 14.57 years, SD = 1.57). Results reveal that loneliness significantly predicts problematic smartphone use, but not vice versa, highlighting a unidirectional influence. The study uncovers crucial differences across educational levels and gender, emphasizing the stronger effect of loneliness on problematic smartphone use among junior high students and female adolescents. These findings underscore the complexity of adolescent loneliness and its relationship with digital behavior, suggesting a need for tailored interventions considering both gender and developmental stages.


Assuntos
Comportamento do Adolescente , Solidão , Smartphone , Humanos , Solidão/psicologia , Adolescente , Feminino , Masculino , Comportamento do Adolescente/psicologia , Estudos Longitudinais , China , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Transtorno de Adição à Internet/psicologia , Fatores Sexuais , Escolaridade
20.
Int J Biol Macromol ; 266(Pt 1): 131187, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38552686

RESUMO

This study introduces a novel temperature-responsive drug delivery system using ethyl cellulose (EC) nanofibers encapsulating a eutectic mixture of lauric acid/stearic acid (LA/SA) as phase change materials (PCMs) and Rhodamine B (RhB) as a model drug. Employing blend electrospinning, the nanofibers achieved controlled drug release responsive to temperature changes. The peak shift of the carbonyl group in FTIR analysis confirmed drug-polymer compatibility, while the absence of RhB peaks in the XRD and DSC assessments revealed RhB's amorphous distribution within the fibers. Our findings demonstrate that RhB release is dependent on its loading, with a slow initial release (<2 %) for 1 % and 5 % RhB loadings and a burst release (~12 %) for 10 % loading. Notably, the release rate was tunable at 37 °C by adjusting LA/SA concentration. The optimal LA/SA loading for temperature-responsive release is identified as 10 %. Over 240 h, there is a 32 % increase in RhB release at 37 °C, and an additional 8 % increase at 40 °C, compared to 25 °C. This research illustrates the potential of PCM-integrated nanofibers in smart drug delivery, particularly for chemotherapy, antibiotics, and anti-inflammatory drugs, showcasing an innovative approach to improving therapeutic efficiency while reducing side effects.

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