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1.
Front Surg ; 11: 1414870, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39108285

RESUMO

Background: Lymph node involvement is recognized as a prognostic factor for patients with gallbladder cancer. However, the N stage varied from different editions of the American Joint Committee on Cancer (AJCC) TNM Classification. Our objective was to investigate the impact of lymph node involvement on overall survival in elderly patients with non-metastatic gallbladder adenocarcinoma. Methods: Patients older than 65 years with non-metastatic gallbladder adenocarcinoma were identified from the SEER data. We used Cox proportional hazard regression analysis to select the independent risk factor. A nomogram was built to identify the 1-, 3-, and 5-years' prognostic impact. Univariate and multivariate models were used to examine the correlation of overall survival (OS) with the number of metastatic nodes. Results: A total of 1,654 patients (706 with and 948 without nodal involvement) were included. Cox proportional hazard regression analyses found that age, gender, tumor size, lymph node involvement, and surgical options were risk factors for the prognosis and were integrated into the nomogram. After adjustment, OS was compromised for patients who receive surgery with nodal involvement [hazard ratio (HR), 2.238; P < 0.01]. Furthermore, after adjustment the presence of more than two metastatic lymph nodes was associated with decreased OS (HR, 3.305; P < 0.01). Conclusions: Our results suggest that lymph node involvement is associated with compromised survival in elderly patients. A nomogram was developed to predict the prognosis of gallbladder cancer. A change point of more than two metastatic lymph nodes seems to carry prognostic significance, calling for closer monitoring of elderly patients with gallbladder cancer with involvement of increased number of lymph nodes.

2.
Int J Biol Macromol ; 277(Pt 4): 134562, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39116982

RESUMO

Antifreeze proteins (AFPs) can inhibit ice crystal growth. The ice-binding mechanism of AFPs remains unclear, yet the hydration shells of AFPs are thought to play an important role in modulating the binding of AFPs and ice. Here, we performed all-atom molecular dynamics simulations of an AFP from Choristoneura fumiferana (CfAFP) at four different temperatures, with a focus on analysis at 240 and 300 K, to investigate the dynamic and thermodynamic characteristics of hydration shells around ice-binding surfaces (IBS) and non-ice-binding surfaces (NIBS). Our results revealed that the dynamics of CfAFP hydration shells were highly heterogeneous, with its IBS favoring a less dense and more tetrahedral solvation shell, and NIBS hydration shells having opposite features to those of the IBS. The IBS of nine typical hyperactive AFPs were found to be in pure low-entropy hydration shell region, indicating that low-entropy hydration shell region of IBS and the tetrahedral arrangements of water molecules around them mediate the ice-binding mechanism of AFPs. It is because the entropy increase of the low-entropy hydration shell around IBS, while the higher entropy water molecules at NIBS most likely prevent ice crystal growth. These findings provide new mechanistic insights into the ice-binding of AFPs.

3.
ACS Appl Mater Interfaces ; 16(28): 36628-36636, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38954707

RESUMO

Real-time detection of harmful gases at room temperature has become a serious problem in public health and environmental monitoring. Two-dimensional materials with semiconductor properties BiOCl is a promising gas-sensitive material due to its large specific surface area and adjustable band gap as well as outstanding safety characteristics. However, limited by the weak gas adsorption sites and sluggish charge-transfer ability, the performance of BiOCl could not be fully exploited. Oxygen vacancy (Vo) engineering can introduce lattice defects, thereby significantly increasing the local charge density and enhancing the adsorption of gases, which is an effective strategy to enhance the gas-sensing performance. In this work, we composite BiOCl with a vacancy (Vo-BiOCl) and reduced graphene oxide (rGO) to construct a Vo-BiOCl/rGO heterostructure with enhanced gas adsorption sites. Experimental and theoretical calculations show that Vo can enhance the adsorption of gases and the introduction of rGO forms a high-quality heterostructure with BiOCl, which can effectively reduce the band gap of BiOCl and promote electron transfer, thereby improving the sensitivity of the sensor. Benefiting from above, Vo-BiOCl/rGO achieves the ability to detect low concentrations of NO2/NH3 at room temperature, with high sensitivity (55% at 1 ppm of NO2 and -28% at 1 ppm of NH3), fast response time (40 s at 1 ppm of NO2 and 2 s at 1 ppm of NH3), good stability (over 150 days), and fully recoverable gas sensitivity.

4.
Age Ageing ; 53(7)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38984695

RESUMO

PURPOSE: This study aimed to develop a normal brain ageing model based on magnetic resonance imaging and radiomics, therefore identifying radscore, an imaging indicator representing white matter heterogeneity and exploring the significance of radscore in detecting people's cognitive changes. METHODS: Three hundred sixty cognitively normal (CN) subjects from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database and 105 CN subjects from the Parkinson's Progression Markers Initiative database were used to develop the model. In ADNI, 230 mild cognitive impairment (MCI) subjects were matched with 230 CN old-aged subjects to evaluate their heterogeneity difference. One hundred four MCI subjects with 48 months of follow-up were divided into low and high heterogeneity groups. Kaplan-Meier survival curve analysis was used to observe the importance of heterogeneity results for predicting MCI progression. RESULTS: The area under the receiver operating characteristic curve of the model in the training, internal test and external test sets was 0.7503, 0.7512 and 0.7514, respectively. There was a significantly positive correlation between age and radscore of CN subjects (r = 0.501; P < .001). The radscore of MCI subjects was significantly higher than that of matched CN subjects (P < .001). The median radscore ratios of MCI to CN from four age groups (66-70y, 71-75y, 76-80y and 81-85y) were 1.611, 1.760, 1.340 and 1.266, respectively. The probability to progression of low and high heterogeneity groups had a significant difference (P = .002). CONCLUSION: When radscore is significantly higher than that of normal ageing, it is necessary to alert the possibility of cognitive impairment and deterioration.


Assuntos
Envelhecimento , Disfunção Cognitiva , Progressão da Doença , Imageamento por Ressonância Magnética , Humanos , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico , Idoso , Masculino , Feminino , Idoso de 80 Anos ou mais , Envelhecimento/psicologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Fatores de Risco , Fatores Etários , Valor Preditivo dos Testes , Cognição , Bases de Dados Factuais , Estudos de Casos e Controles , Medição de Risco , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Radiômica
6.
World J Surg Oncol ; 22(1): 165, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918808

RESUMO

BACKGROUND: The purpose of this study was to compare safety and efficacy outcomes between immediate breast reconstruction (IBR) and mastectomy alone in locally advanced breast cancer patients. METHODS: We conducted a comprehensive literature search of PUBMED, EMBASE, and Cochrane databases. The primary outcomes evaluated were overall survival, disease-free survival, and local recurrence. The secondary outcome was the incidence of surgical complications. All data were analyzed using Review Manager 5.3. RESULTS: Sixteen studies, involving 15,364 participants were included in this meta-analysis. Pooled data demonstrated that patients underwent IBR were more likely to experience surgical complications than those underwent mastectomy alone (HR: 3.96, 95%CI [1.07,14.67], p = 0.04). No significant difference was found in overall survival (HR: 0.94, 95%CI [0.73,1.20], p = 0.62), disease-free survival (HR: 1.03, 95%CI [0.83,1.27], p = 0.81), or breast cancer specific survival (HR: 0.93, 95%CI [0.71,1.21], p = 0.57) between IBR group and Non-IBR group. CONCLUSIONS: Our study demonstrates that IBR after mastectomy does not affect the overall survival and disease-free survival of locally advanced breast cancer patients. However, IBR brings with it a nonnegligible higher risk of complications and needs to be fully evaluated and carefully decided.


Assuntos
Neoplasias da Mama , Mamoplastia , Mastectomia , Complicações Pós-Operatórias , Humanos , Feminino , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Neoplasias da Mama/mortalidade , Mastectomia/efeitos adversos , Mastectomia/métodos , Mamoplastia/métodos , Mamoplastia/efeitos adversos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Prognóstico , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/etiologia , Taxa de Sobrevida
7.
World J Clin Cases ; 12(17): 3206-3213, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38898831

RESUMO

BACKGROUND: Function-preserving pancreatectomy can improve the long-term quality of life of patients with benign or low-grade malignant tumors, such as intraductal papillary mucinous neoplasms (IPMNs) and mucinous cystic neoplasms. However, there is limited literature on laparoscopic spleen-preserving total pancreatectomy (L-SpTP) due to technical difficulties. CASE SUMMARY: Patient 1 was a 51-year-old male diagnosed with IPMN based on preoperative imaging, showing solid nodules in the pancreatic head and diffuse dilation of the main pancreatic duct with atrophy of the distal pancreas. We performed L-SpTP with preservation of the splenic vessels, and the postoperative pathology report revealed IPMN with invasive carcinoma. Patient 2 was a 60-year-old male with multiple cystic lesions in the pancreatic head and body. L-SpTP was performed, and intraoperatively, the splenic vein was injured and required ligation. Postoperative pathology revealed a mucinous cystic tumor of the pancreas with low-grade dysplasia. Both patients were discharged on postoperative day 7, and there were no major complications during the perioperative period. CONCLUSION: We believe that L-SpTP is a safe and feasible treatment for low-grade malignant pancreatic tumors, but more case studies are needed to evaluate its safety, efficacy, and long-term outcomes.

8.
Discov Oncol ; 15(1): 218, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856944

RESUMO

The role of cathepsin K (CTSK) expression in the pathogenesis and progression of gastric cancer (GC) remains unclear. Hence, the primary objective of this study is to elucidate the precise expression and biological role of CTSK in GC by employing a combination of bioinformatics analysis and in vitro experiments. Our findings indicated a significant upregulation of CTSK in GC. The bioinformatics analysis revealed that GC patients with a high level of CTSK expression exhibited enrichment of hallmark gene sets associated with angiogenesis, epithelial-mesenchymal transition (EMT), inflammatory response, KRAS signaling up, TNFα signaling via KFκB, IL2-STAT5 signaling, and IL6-JAK-STAT3 signaling. Additionally, these patients demonstrated elevated levels of M2-macrophage infiltration, which was also correlated with a poorer prognosis. The results of in vitro experiments provided confirmation that the over-expression of CTSK leads to an increase in the proliferative and invasive abilities of GC cells. However, further evaluation was necessary to determine the impact of CTSK on the migration capability of these cells. Our findings suggested that CTSK has the potential to facilitate the initiation and progression of GC by augmenting the invasive capacity of GC cells, engaging in tumor-associated EMT, and fostering the establishment of an immunosuppressive tumor microenvironment (TME).

9.
Nano Lett ; 24(26): 8098-8106, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38913786

RESUMO

The development of multifunctional MXene-based fabrics for smart textiles and portable devices has garnered significant attention. However, very limited studies have focused on their structure design and associated mechanical properties. Here, the supertough MXene fiber felts composed of MXene/sodium alginate (SA) fibers were fabricated. The fracture strength and bending stiffness of felts can be up to 97.8 MPa and 1.04 N mm2, respectively. Besides, the fracture toughness of felts was evaluated using the classic Griffith theory, yielding to a critical stress intensity factor of 1.79 MPam. In addition, this kind of felt presents outstanding electrothermal conversion performance (up to 119 °C at a voltage of 2.5 V), high cryogenic and high-temperature tolerance of photothermal conversion performance (-196 to 160 °C), and excellent electromagnetic interference (EMI) shielding effectiveness (54.4 dB in the X-band). This work provides new structural design concepts for high-performance MXene-based textiles, broadening their future applications.

10.
ACS Appl Bio Mater ; 7(5): 3283-3294, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38727030

RESUMO

Medical implants are constantly facing the risk of bacterial infections, especially infections caused by multidrug resistant bacteria. To mitigate this problem, gold nanoparticles with alkyl bromide moieties (Au NPs-Br) on the surfaces were prepared. Xenon light irradiation triggered the plasmon effect of Au NPs-Br to induce free radical graft polymerization of 2-(dimethylamino)ethyl methacrylate (DMAEMA), leading to the formation of poly(DMAEMA) brush-grafted Au NPs (Au NPs-g-PDM). The Au NPs-g-PDM nanocomposites were conjugated with phytic acid (PA) via electrostatic interaction and van der Waals interaction. The as-formed aggregates were deposited on the titanium (Ti) substrates to form the PA/Au NPs-g-PDM (PAP) hybrid coatings through surface adherence of PA and the gravitational effect. Synergistic bactericidal effects of contact-killing caused by the cationic PDM brushes, and local heating generated by the Au NPs under near-infrared irradiation, conferred strong antibacterial effects on the PAP-deposited Ti (Ti-PAP) substrates. The synergistic bactericidal effects reduced the threshold temperature required for the photothermal sterilization, which in turn minimized the secondary damage to the implant site. The Ti-PAP substrates exhibited 97.34% and 99.97% antibacterial and antiadhesive efficacy, respectively, against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), compared to the control under in vitro antimicrobial assays. Furthermore, the as-constructed Ti-PAP surface exhibited a 99.42% reduction in the inoculated S. aureus under in vivo assays. In addition, the PAP coatings exhibited good biocompatibility in the hemolysis and cytotoxicity assays as well as in the subcutaneous implantation of rats.


Assuntos
Antibacterianos , Escherichia coli , Ouro , Teste de Materiais , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Ácido Fítico , Staphylococcus aureus , Ouro/química , Ouro/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Nanopartículas Metálicas/química , Ácido Fítico/química , Ácido Fítico/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Animais , Propriedades de Superfície , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Cátions/química , Cátions/farmacologia , Polímeros/química , Polímeros/farmacologia , Titânio/química , Titânio/farmacologia
11.
Surg Obes Relat Dis ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38782612

RESUMO

BACKGROUND: Bile acids can stimulate the secretion of glucagon-like peptide-1 (GLP-1) and be mostly reabsorbed in the ileum. OBJECTIVES: We aimed to investigate whether ileum excision could reverse the glucose improvement after biliopancreatic diversion with duodenal switch (BPD/DS). SETTING: Peking Union Medical College Hospital. METHODS: Thirty diabetic rats were randomly divided into the BPD/DS group, BPD/DS plus ileectomy (BDI) group, and control group. The fasting blood glucose, bile acids, and glucagon-like peptide-1(GLP-1) levels in plasma samples were analyzed. RESULTS: In postoperative week 20, the fasting blood glucose level in the BDI group was significantly higher than that in the BPD/DS group (11.5 ± 1.4 mmol/L versus 7.6 ± 1.0 mmol/L, P < .001), and the AUCOGTT value was also significantly higher than that in the BPD/DS group (2186.1 ± 237.2 mmol/L·min versus 1551.2 ± 136.9 mmol/L·min, P < .001). The plasma level of bile acids in the BDI group was lower than that in the BPD/DS group (P = .012) and was not significantly different from that in the control group (P = .629). The plasma level of GLP-1 in the BDI group was lower than that in the BPD/DS group (P = .009) and was not significantly different from that in the control group (P = .530). Moreover, the intestinal TGR5 expression in the BDI group was significantly lower than that in the BPD/DS group (P < .001). CONCLUSIONS: The results show that excision of the ileum can partially reverse the improvement in glucose metabolism after BPD/DS.

12.
ACS Appl Mater Interfaces ; 16(20): 26674-26684, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38717387

RESUMO

Flexible pressure sensors have attracted great interest as they play an important role in various fields such as health monitoring and human-machine interactions. The design of the pressure sensors still faces challenges in achieving a high sensitivity for a wide sensing range, and the interference of water restricts the applications of the sensors. Herein, we developed a graphene-polydimethylsiloxane film combining a hierarchical surface with nanowrinkles on it and a hollow structure. The microstructure design of the composite can be facilely controlled to improve the sensing and hydrophobic performance by tailoring the microsphere building units. Attributed to the irregular surface and hollow structure of the sensing layer, the optimized sensor exhibits a superior sensitivity of 1085 kPa-1 in a 50 kPa linear range. For practical applications, the nanowrinkles on the surface of the microspheres and the polymer coating endow the composite with waterproof properties. Inspired by the dual receptors of the skin, two designed microstructured films can simply integrate into one with double-sided microstructures. The sensing performance and the water-repellence property allow the sensor to detect physiological signals under both ambient and underwater conditions. Furthermore, underwater stimuli detection and communication are demonstrated. This method of fabricating a flexible sensor shows great potential in wearable and robotic fields.

13.
Nat Commun ; 15(1): 4512, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802369

RESUMO

In higher plants, mature male gametophytes have distinct apertures. After pollination, pollen grains germinate, and a pollen tube grows from the aperture to deliver sperm cells to the embryo sac, completing fertilization. In rice, the pollen aperture has a single-pore structure with a collar-like annulus and a plug-like operculum. A crucial step in aperture development is the formation of aperture plasma membrane protrusion (APMP) at the distal polar region of the microspore during the late tetrad stage. Previous studies identified OsINP1 and OsDAF1 as essential regulators of APMP and pollen aperture formation in rice, but their precise molecular mechanisms remain unclear. We demonstrate that the Poaceae-specific OsSRF8 gene, encoding a STRUBBELIG-receptor family 8 protein, is essential for pollen aperture formation in Oryza sativa. Mutants lacking functional OsSRF8 exhibit defects in APMP and pollen aperture formation, like loss-of-function OsINP1 mutants. OsSRF8 is specifically expressed during early anther development and initially diffusely distributed in the microsporocytes. At the tetrad stage, OsSRF8 is recruited by OsINP1 to the pre-aperture region through direct protein-protein interaction, promoting APMP formation. The OsSRF8-OsINP1 complex then recruits OsDAF1 to the APMP site to co-regulate annulus formation. Our findings provide insights into the mechanisms controlling pollen aperture formation in cereal species.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Pólen , Oryza/genética , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Pólen/metabolismo , Pólen/genética , Pólen/crescimento & desenvolvimento , Mutação , Polinização , Membrana Celular/metabolismo , Plantas Geneticamente Modificadas , Tubo Polínico/metabolismo , Tubo Polínico/crescimento & desenvolvimento , Tubo Polínico/genética
14.
J Cell Mol Med ; 28(9): e18328, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38683130

RESUMO

Gallbladder cancer is a rare but fatal malignancy. However, the mechanisms underlying gallbladder carcinogenesis and its progression are poorly understood. The function of m6A modification and its regulators was still unclear for gallbladder cancer. The current study seeks to investigate the function of YTH m6A RNA-binding protein 1 (YTHDF1) in gallbladder cancer. Transcriptomic analysis and immunochemical staining of YTHDF1 in gallbladder cancer tissues revealed its upregulation compared to paracancerous tissues. Moreover, YTHDF1 promotes the proliferation assays, Transwell migration assays, and Transwell invasion assays of gallbladder cancer cells in vitro. And it also increased tumour growth in xenograft mouse model and metastases in tail vein injection model in vivo. In vitro, UHRF1 knockdown partly reversed the effects of YTHDF1 overexpression. Mechanistically, dual-luciferase assays proved that YTHDF1 promotes UHRF1 expression via direct binding to the mRNA 3'-UTR in a m6A-dependent manner. Overexpression of YTHDF1 enhanced UHRF1 mRNA stability, as demonstrated by mRNA stability assays, and Co-IP studies confirmed a direct interaction between YTHDF1 and PABPC1. Collectively, these findings provide new insights into the progression of gallbladder cancer as well as a novel post-transcriptional mechanism of YTHDF1 via stabilizing target mRNA.


Assuntos
Adenosina , Neoplasias da Vesícula Biliar , Regulação Neoplásica da Expressão Gênica , Proteínas de Ligação a RNA , Ubiquitina-Proteína Ligases , Animais , Feminino , Humanos , Masculino , Camundongos , Adenosina/análogos & derivados , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Proteínas Estimuladoras de Ligação a CCAAT/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Neoplasias da Vesícula Biliar/genética , Neoplasias da Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/metabolismo , Camundongos Nus , Estabilidade de RNA/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética
15.
Sci Total Environ ; 931: 172708, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38677416

RESUMO

Recognizing the origins and movement processes of surface water and groundwater is crucial for understanding hydrochemical genesis, conserving water supplies, and managing water resources. Estimating the source water typically involves identifying the intersection of evaporation line (EL) and meteoric water line. However, there is currently confusion in determining the regional EL and selecting strategies for estimating the source water. This study aimed to explore the source of surface water and groundwater, as well as evaporation effect utilizing stable isotope tracing (δ2H and δ18O). The line-conditioned excess was adopted to differentiate evaporated water and non-evaporated water, then Craig-Gordon model and an analytical framework with Bayesian theory were used to investigate the source of surface water and groundwater and the evaporation influence. The findings revealed that surface water and groundwater in the northern region of the Weihe River suffered more sever evaporation impacts that the south, and the evaporated surface water (7.54 % to 27.34 %) with a wider range of mean evaporation ratio than evaporated groundwater (5.38 % to 8.52 %). Monsoon precipitation is the main contributor to both surface water (contribution ratio: 0.46) and groundwater (0.49) sources. This research provides specific information on evaporation and detailed insights into the source water of surface water and groundwater, aiding in understanding the evaporation effect during the hydrological cycle and facilitating the management of regional water resources.

16.
ACS Appl Mater Interfaces ; 16(17): 22547-22557, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38628112

RESUMO

Soft actuators with stimuli-responsive and reversible deformations have shown great promise in soft robotics. However, some challenges remain in existing actuators, such as the materials involved derived from nonrenewable resources, complex and nonscalable preparation methods, and incapability of complex and programmable deformation. Here, a biobased ink based on cuttlefish ink nanoparticles (CINPs) and cellulose nanofibers (CNFs) was developed, allowing for the preparation of biodegradable patterned actuators by direct ink writing technology. The hybrid CNF/CINP ink displays good rheological properties, allowing it to be accurately printed on a variety of flexible substrates. A bilayer actuator was developed by printing an ink layer on a biodegradable poly(lactic acid) film using extrusion-based 3D printing technology, which exhibits reversible and large bending behavior under the stimuli of humidity and light. Furthermore, programmable and reversible folding and coiling deformations in response to stimuli have been achieved by adjusting the ink patterns. This work offers a fast, scalable, and cost-effective strategy for the development of biodegradable patterned actuators with programmable shape-morphing.

17.
Front Aging Neurosci ; 16: 1366780, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38685908

RESUMO

Objective: Voxel-based morphometry (VBM), surface-based morphometry (SBM), and radiomics are widely used in the field of neuroimage analysis, while it is still unclear that the performance comparison between traditional morphometry and emerging radiomics methods in diagnosing brain aging. In this study, we aimed to develop a VBM-SBM model and a radiomics model for brain aging based on cognitively normal (CN) individuals and compare their performance to explore both methods' strengths, weaknesses, and relationships. Methods: 967 CN participants were included in this study. Subjects were classified into the middle-aged group (n = 302) and the old-aged group (n = 665) according to the age of 66. The data of 360 subjects from the Alzheimer's Disease Neuroimaging Initiative were used for training and internal test of the VBM-SBM and radiomics models, and the data of 607 subjects from the Australian Imaging, Biomarker and Lifestyle, the National Alzheimer's Coordinating Center, and the Parkinson's Progression Markers Initiative databases were used for the external tests. Logistics regression participated in the construction of both models. The area under the receiver operating characteristic curve (AUC), sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were used to evaluate the two model performances. The DeLong test was used to compare the differences in AUCs between models. The Spearman correlation analysis was used to observe the correlations between age, VBM-SBM parameters, and radiomics features. Results: The AUCs of the VBM-SBM model and radiomics model were 0.697 and 0.778 in the training set (p = 0.018), 0.640 and 0.789 in the internal test set (p = 0.007), 0.736 and 0.737 in the AIBL test set (p = 0.972), 0.746 and 0.838 in the NACC test set (p < 0.001), and 0.701 and 0.830 in the PPMI test set (p = 0.036). Weak correlations were observed between VBM-SBM parameters and radiomics features (p < 0.05). Conclusion: The radiomics model achieved better performance than the VBM-SBM model. Radiomics provides a good option for researchers who prioritize performance and generalization, whereas VBM-SBM is more suitable for those who emphasize interpretability and clinical practice.

18.
Small ; : e2401635, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607950

RESUMO

Vapor-driven smart Janus materials have made significant advancements in intelligent monitoring, control, and interaction, etc. Nevertheless, the development of ultrafast response single-layer Janus membrane, along with a deep exploration of the smart response mechanisms, remains a long-term endeavor. Here, the successful synthesis of a high-crystallinity single-layer Covalent organic framework (COF) Janus membrane is reported by morphology control. This kind of membrane displays superior mechanical properties and specific surface area, along with excellent responsiveness to CH2Cl2 vapor. The analysis of the underlying mechanisms reveals that the vapor-induced breathing effect of the COF and the stress mismatch of the Janus structure play a crucial role in its smart deformation performance. It is believed that this COF Janus membrane holds promise for complex tasks in various fields.

19.
ACS Nano ; 18(15): 10485-10494, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38564695

RESUMO

Producing high-quality two-dimensional (2D) covalent organic frameworks (COFs) is crucial for industrial applications. However, this remains significantly challenging with current synthetic techniques. A deep understanding of the intermolecular interactions, reaction temperature, and oligomers is essential to facilitate the growth of highly crystalline COF films. Herein, molecular dynamics simulations were employed to explore the growth of 2D COFs from monomer assemblies on graphene. Our results showed that chain growth reactions dominated the COF surface growth and that van der Waals (vdW) interactions were important in enhancing the crystallinity through monomer preorganization. Moreover, appropriately tuning the reaction temperature improved the COF crystallinity and minimized the effects of amorphous oligomers. Additionally, the strength of the interface between the COF and the graphene substrate indicated that the adhesion force was proportional to the crystallinity of the COF. This work reveals the mechanisms for nucleation and growth of COFs on surfaces and provides theoretical guidance for fabricating high-quality 2D polymer-based crystalline nanomaterials.

20.
Nano Lett ; 24(14): 4248-4255, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38557042

RESUMO

Grain boundaries (GBs) in two-dimensional (2D) covalent organic frameworks (COFs) unavoidably form during the fabrication process, playing pivotal roles in the physical characteristics of COFs. Herein, molecular dynamics simulations were employed to elucidate the fracture failure and thermal transport mechanisms of polycrystalline COFs (p-COFs). The results revealed that the tilt angle of GBs significantly influences out-of-plane wrinkles and residual stress in monolayer p-COFs. The tensile strength of p-COFs can be enhanced and weakened with the tilt angle, which exhibits an inverse relationship with the defect density. The crack always originates from weaker heptagon rings during uniaxial tension. Notably, the thermal transport in p-COFs is insensitive to the GBs due to the variation of minor polymer chain length at defects, which is abnormal for other 2D crystalline materials. This study contributes insights into the impact of GBs in p-COFs and offers theoretical guidance for structural design and practical applications of advanced COFs.

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