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1.
Materials (Basel) ; 17(10)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38793474

RESUMO

Low-alloy wear-resistant steel often requires the addition of trace alloy elements to enhance its performance while also considering the cost-effectiveness of production. In order to comparatively analyze the strengthening mechanisms of Mo and Cr elements and further explore economically feasible production processes, we designed two types of low-alloy wear-resistant steels, based on C-Mn series wear-resistant steels, with individually added Mo and Cr elements, comparing and investigating the roles of the alloying elements Mo and Cr in low-alloy wear-resistant steels. Utilizing JMatPro software to calculate Continuous Cooling Transformation (CCT) curves, conducting thermal simulation quenching experiments using a Gleeble-3800 thermal simulator, and employing equipment such as a metallographic microscope, transmission electron microscope, and tensile testing machine, this study comparatively investigated the influence of Mo and Cr on the microstructural transformation and mechanical properties of low-alloy wear-resistant steels under different cooling rates. The results indicate that the addition of the Mo element in low-alloy wear-resistant steel can effectively suppress the transformation of ferrite and pearlite, reduce the martensitic transformation temperature, and lower the critical cooling rate for complete martensitic transformation, thereby promoting martensitic transformation. Adding Cr elements can reduce the austenite transformation zone, decrease the rate of austenite formation, and promote the occurrence of low-temperature phase transformation. Additionally, Mo has a better effect on improving the toughness of low-temperature impact, and Cr has a more significant improvement in strength and hardness. The critical cooling rates of C-Mn-Mo steel and C-Mn-Cr steel for complete martensitic transition are 13 °C/s and 24 °C/s, respectively. With the increase in the cooling rate, the martensitic tissues of the two experimental steels gradually refined, and the characteristics of the slats gradually appeared. In comparison, the C-Mn-Mo steel displays a higher dislocation density, accompanied by dislocation entanglement phenomena, and contains a small amount of residual austenite, while granular ε-carbides are clearly precipitated in the C-Mn-Cr steel. The C-Mn-Mo steel achieves its best performance at a cooling rate of 25 °C/s, whereas the C-Mn-Cr steel only needs to increase the cooling rate to 35 °C/s to attain a similar comprehensive performance to the C-Mn-Mo steel.

2.
Int J Biol Macromol ; 269(Pt 1): 131794, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38697434

RESUMO

A middle ear infection occurs due to the presence of several microorganisms behind the eardrum (tympanic membrane) and is very challenging to treat due to its unique location and requires a well-designed treatment. If not treated properly, the infection can result in severe symptoms and unavoidable side effects. In this study, excellent biocompatible ethyl cellulose (EC) and biodegradable polyhydroxybutyrate (PHB) biopolymer were used to fabricate drug-loaded nanofiber scaffolds using an electrospinning technique to overcome antibiotic overdose and insufficient efficacy of drug release during treatment. PHB polymer was produced from Halomonas sp., and the purity of PHB was found to around be 90 %. Additionally, ciprofloxacin (CIP) and amoxicillin (AMX) are highly preferable since both drugs are highly effective against gram-negative and gram-positive bacteria to treat several infections. Obtained smooth nanofibers were between 116.24 and 171.82 nm in diameter and the addition of PHB polymer and antibiotics improved the morphology of the nanofiber scaffolds. Thermal properties of the nanofiber scaffolds were tested and the highest Tg temperature resulted at 229 °C. The mechanical properties of the scaffolds were tested, and the highest tensile strength resulted in 4.65 ± 6.33 MPa. Also, drug-loaded scaffolds were treated against the most common microorganisms that cause the infection, such as S.aureus, E.coli, and P.aeruginosa, and resulted in inhibition zones between 10 and 21 mm. MTT assay was performed by culturing human adipose-derived mesenchymal stem cells (hAD MSCs) on the scaffolds. The morphology of the hAD MSCs' attachment was tested with SEM analysis and hAD MSCs were able to attach, spread, and live on each scaffold even on the day of 7. The cumulative drug release kinetics of CIP and AMX from drug-loaded scaffolds were analysed in phosphate-buffered saline (pH: 7.4) within different time intervals of up to 14 days using a UV spectrophotometer. Furthermore, the drug release showed that the First-Order and Korsmeyer-Peppas models were the most suitable kinetic models. Animal testing was performed on SD rats, matrix and collagen deposition occurred on days 5 and 10, which were observed using Hematoxylin-eosin and Masson's trichrome staining. At the highest drug concentration, a better repair effect was observed. Results were promising and showed potential for novel treatment.


Assuntos
Amoxicilina , Antibacterianos , Celulose , Ciprofloxacina , Nanofibras , Celulose/química , Celulose/análogos & derivados , Ciprofloxacina/farmacologia , Ciprofloxacina/química , Nanofibras/química , Animais , Ratos , Amoxicilina/farmacologia , Amoxicilina/química , Antibacterianos/farmacologia , Antibacterianos/química , Hidroxibutiratos/química , Hidroxibutiratos/farmacologia , Humanos , Otite Média/tratamento farmacológico , Otite Média/microbiologia , Poliésteres/química , Liberação Controlada de Fármacos , Alicerces Teciduais/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Proibitinas , Portadores de Fármacos/química , Masculino
3.
Small ; : e2400850, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38616735

RESUMO

Membrane-based osmotic energy harvesting is a promising technology with zero carbon footprint. High-performance ion-selective membranes (ISMs) are the core components in such applications. Recent advancement in 2D nanomaterials opens new avenues for building highly efficient ISMs. However, the majority of the explored 2D nanomaterials have a negative surface charge, which selectively enhances cation transport, resulting in the underutilization of half of the available ions. In this study, ISMs based on layered double hydroxide (LDH) with tunable positive surface charge are studied. The membranes preferentially facilitate anion transport with high selectivity. Osmotic energy harvesting device based on these membranes reached a power density of 2.31 W m-2 under simulated river/sea water, about eight times versus that of a commercial membrane tested under the same conditions, and up to 7.05 W m-2 under elevated temperature and simulated brine/sea water, and long-term stability with consistent performance over a 40-day period. A prototype reverse electrodialysis energy harvesting device, comprising a pair of LDH membranes and commercial cation-selective membranes, is able to simultaneously harvest energy from both cations and anions achieving a power density of 6.38 W m-2 in simulated river/sea water, demonstrating its potential as building blocks for future energy harvesting systems.

4.
Carbohydr Polym ; 336: 122102, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38670773

RESUMO

Skin wounds are susceptible to infection, leading to severe inflammatory reactions that can progress to chronic wounds, ultimately causing significant physical and mental distress to the patient. In this study, we propose an injectable composite hydrogel achieved through one-pot gelation of oxidized xyloglucan (OXG), cationic polyamide ε-poly-l-lysine (EPL), and surface amino-rich silicon nanoparticles (SiNPs). OXG exhibits commendable anti-inflammatory properties and provides crosslinking sites. SiNPs serve as mechanically reinforced crosslinkers, facilitating the construction of a dynamic Schiff base network. SiNPs significantly reduced the gelation time to 3 s and tripled the storage modulus of the hydrogels. Additionally, the combination of EPL and SiNPs demonstrated synergistic antimicrobial activity against both S. aureus and E. coli. Notably, the hydrogel effectively halted liver bleeding within 30 s. The hydrogel demonstrated outstanding shear-thinning and self-healing properties, crucial considerations for the design of injectable hydrogels. Furthermore, its efficacy was evaluated as a wound dressing in a mouse model with S. aureus infection. The results indicated that, compared to commercial products, the hydrogel exhibited a shorter wound healing time, decreased inflammation, thinner epithelium, increased hair follicles, enhanced neovascularization, and more substantial collagen deposition. These findings strongly suggest the promising potential of the proposed hydrogel as an effective wound dressing for the treatment of infected wounds.


Assuntos
Antibacterianos , Escherichia coli , Glucanos , Hidrogéis , Nanopartículas , Polilisina , Staphylococcus aureus , Cicatrização , Xilanos , Glucanos/química , Glucanos/farmacologia , Animais , Cicatrização/efeitos dos fármacos , Xilanos/química , Xilanos/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Polilisina/química , Polilisina/farmacologia , Camundongos , Nanopartículas/química , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/administração & dosagem , Infecções Estafilocócicas/tratamento farmacológico , Reagentes de Ligações Cruzadas/química , Infecção dos Ferimentos/tratamento farmacológico , Masculino
5.
Int J Biol Macromol ; 266(Pt 1): 131170, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554906

RESUMO

Skin wound healing is a complex and dynamic process involving hemostasis, inflammatory response, cell proliferation and migration, and angiogenesis. Currently used wound dressings remain unsatisfactory in the clinic due to the lack of adjustable mechanical property for injection operation and bioactivity for accelerating wound healing. In this work, an "all-sugar" hydrogel dressing is developed based on dynamic borate bonding network between the hydroxyl groups of okra polysaccharide (OP) and xyloglucan (XG). Benefiting from the reversible crosslinking network, the resulting composite XG/OP hydrogels exhibited good shear-thinning and fast self-healing properties, which is suitable to be injected at wound beds and filled into irregular injured site. Besides, the proposed XG/OP hydrogels showed efficient antioxidant capacity by scavenging DPPH activity of 73.9 %. In vivo experiments demonstrated that XG/OP hydrogels performed hemostasis and accelerated wound healing with reduced inflammation, enhanced collagen deposition and angiogenesis. This plant-derived dynamic hydrogel offers a facile and effective approach for wound management and has great potential for clinical translation in feature.


Assuntos
Antioxidantes , Hidrogéis , Neovascularização Fisiológica , Polissacarídeos , Cicatrização , Cicatrização/efeitos dos fármacos , Hidrogéis/química , Hidrogéis/farmacologia , Antioxidantes/farmacologia , Antioxidantes/química , Animais , Polissacarídeos/química , Polissacarídeos/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Abelmoschus/química , Glucanos/química , Glucanos/farmacologia , Xilanos/química , Xilanos/farmacologia , Camundongos , Ratos , Masculino , Humanos , Angiogênese
6.
Adv Healthc Mater ; : e2400071, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38501563

RESUMO

The treatment of infected wounds remains a challenging biomedical problem. Some bioactive small-molecule hydrogelators with unique rigid structures can self-assemble into supramolecular hydrogels for wound healing. However, they are still suffered from low structural stability and bio-functionality. Herein, a supramolecular hydrogel antibacterial dressing with a dual nanofibrillar network structure is proposed. A nanofibrillar network created by a small-molecule hydrogelator, puerarin extracted from the traditional Chinese medicine Pueraria, is interconnected with a secondary macromolecular silk fibroin nanofibrillar network induced by Ga ions via charge-induced supramolecular self-assembly. The resulting hydrogel features adequate mechanical strength for sustainable retention at wounds. Good biocompatibility and efficient bacterial inhibition are obtained when the Ga ion concentration is 0.05%. Otherwise, the substantial release of Ga ions and puerarin endows the hydrogel with excellent hemostatic and antioxidative properties. In vivo, evaluation of a mouse-infected wound model demonstrates that its healing effect outperformed that of a commercially available silver-containing wound dressing. The experimental group successfully achieves a 100% wound closure rate on day 10. This study sheds new light on the design of nanofibrillar hydrogels based on supramolecular self-assembly of naturally derived bioactive molecules as well as their clinical use for treating chronic infected wounds.

7.
IEEE Trans Med Imaging ; PP2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38163306

RESUMO

Medical image segmentation is crucial in clinical diagnosis, helping physicians identify and analyze medical conditions. However, this task is often accompanied by challenges like sensitive data, privacy concerns, and expensive annotations. Current research focuses on personalized collaborative training of medical segmentation systems, ignoring that obtaining segmentation annotations is time-consuming and laborious. Achieving a perfect balance between annotation cost and segmentation performance while ensuring local model personalization has become a valuable direction. Therefore, this study introduces a novel Model-Heterogeneous Semi-Supervised Federated (HSSF) Learning framework. It proposes Regularity Condensation and Regularity Fusion to transfer autonomously selective knowledge to ensure the personalization between sites. In addition, to efficiently utilize unlabeled data and reduce the annotation burden, it proposes a Self-Assessment (SA) module and a Reliable Pseudo-Label Generation (RPG) module. The SA module generates self-assessment confidence in real-time based on model performance, and the RPG module generates reliable pseudo-label based on SA confidence. We evaluate our model separately on the Skin Lesion and Polyp Lesion datasets. The results show that our model performs better than other methods characterized by heterogeneity. Moreover, it exhibits highly commendable performance even in homogeneous designs, most notably in region-based metrics. The full range of resources can be readily accessed through the designated repository located at HSSF(github.com) on the platform of GitHub.

8.
J Environ Manage ; 348: 119216, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37839209

RESUMO

Invasive Spartina alterniflora has become a global management challenge in coastal wetlands. China has decided to eradicate it completely, but the high costs and its provision of beneficial ecosystem functions (EF, in the form of blue carbon and coastal protection) have raised concerns about its removal. Here, using the Yangtze Estuary as a case study, we explore a reasonable pathway of S. alterniflora management that balanced control of invasive species and EF. We simulated the spatial patterns of two key EF - blue carbon storage and wave attenuation - and identified appropriate zones for eradicating S. alterniflora based on their trade-offs. We observed contrasting patterns along the land-sea gradient for S. alterniflora community, with a decrease in blue carbon storage and an increase in wave attenuation. Notably, pioneer S. alterniflora near the foreshore displayed a high cluster of blue carbon storage (63.61 ± 7.33 Mg C ha-1) and dissipated nearly 70% of wave energy by a width of 163 m. The trade-offs between the two EF indicated that the eradication project should be implemented along the seawall rather than the foreshore. Even in the scenario of prioritized shore defense with the largest eradication zone, S. alterniflora still stored 43.1% more carbon (10.67 Gg C) compared to complete eradication and dissipated over 70% of wave energy in extreme events. Our study innovatively integrates eradication and reservation in S. alterniflora management, providing a sustainable and flexible spatial strategy that meets the needs of stakeholders.


Assuntos
Ecossistema , Áreas Alagadas , Poaceae/metabolismo , Espécies Introduzidas , China , Carbono/análise
9.
Materials (Basel) ; 16(18)2023 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-37763528

RESUMO

With the acceleration of the construction of sponge cities in China, porous asphalt pavement (PA) is has been widely used. High-viscosity asphalt (HVA) is the core material in building PA because it has good rheology properties, which can provide good raveling and rutting resistance. However, due to the open-graded structure of PA, HVA was more susceptible to rapid aging, which significantly affects the durability of PA. To investigate the thermal aging effect on the rheological properties of self-modified HVA (SHVA), five types of asphalts were aged using a rolling thin film oven (RTFO) and pressure aging vessel (PAV). Then, rheological tests were adopted, such as temperature sweep test (TS), repeated creep and recovery test (RCR), and bending beam rheometer test (BBR). The results indicate that during the aging process, the oxidation-induced hardening effect of neat asphalt and the degradation-induced softening effect of the modifier changes the rheology properties of HVA significantly. As the aging progresses, the contribution of the modifiers of HVA to anti-aging performance is greatly reduced. At high temperatures, HVA demonstrates better anti-aging performance than conventional styrene-butadiene-styrene (SBS)-modified asphalt (Guo Chuang, GC). The change of the high-temperature rheological indices of the two HVA types (SHVA and TAFPACK-super HVA (TPS)) showed a smaller activation energy index (EAI), a more considerable viscous component of binder creep stiffness (Gv), and more minor accumulated stain (racc), indicating a more significant anti-short-term and long-term aging performance, which is beneficial to the high-temperature performance of asphalts. However, the changes in low-temperature rheological properties do not align with those in high-temperature rheological properties after long-term aging. The BBR test results reveal that TPS exhibits worse low-temperature performance than GC and SHVA. During the thermal aging process, the contribution rate of the modifiers in SHVA against RTFO and PAV aging is higher than that of the modifiers in TPS, which contributes to the superior anti-aging property. Overall, SHVA demonstrates the best anti-aging performance among the five asphalts tested.

10.
Front Microbiol ; 14: 1184869, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37389332

RESUMO

Background: Gut microbiome plays an indispensable role in the occurrence and progression in various diseases. The incidence of pancreatic cancer (PC) and liver metastasis (PCLM) are high, most of them are found in advanced stage. Therefore, it is particularly necessary to search for predictive biomarkers, which are helpful for early detection and treatment, and thus improve the survival rate and quality of life of PC patients. Methods: We retrospectively analyzed 44 pancreatic cancer patients (P group, n = 44) and 50 healthy people (N group, n = 50) from March 21, 2021 and August 2, 2022. Among all PC patients, we divided them into liver metastasis group (LM group, n = 27) and non-liver metastasis group (non-LM group, n = 17). DNA was extracted and 16S ribosomal RNA (16S rRNA) gene sequencing was performed. SPSS was used for statistical analyses and all bioinformatics analyses were based on QIIME2, p < 0.05 were considered statistically significant. Results: The microbial richness and diversity of group P and LM were higher than that of group N and non-LM. LEfSe analysis found that Streptococcus was a significantly different microorganism, which was further identified by random forest (RF) model, and its ability to predict PC and PCLM was verified by ROC curve. Conclusion: We demonstrated significant differences in intestinal microbiome composition between PC patients and healthy people, and found that Streptococcus is a potential biomarker for early prediction of PC and PCLM, which is critical for early diagnosis of diseases.

11.
Carbohydr Polym ; 313: 120904, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37182937

RESUMO

Delayed or chronic wound healing is one of severe clinical issues. Developing scaffold materials capable of supporting cells and inducing tissue regeneration remains a challenge. Here, a polysaccharide-based hydrogel is constructed for promoting full-thickness skin wound healing in mouse model. The engineering hydrogel consists of a dynamic crosslinking network formed by the Schiff base reaction between aldehyde-containing xyloglucan and methacrylated chitosan. Its reversible gel-sol-gel transition upon shearing force is highly beneficial to completely cover and fill irregular wound shape. The second covalent cross-linking network achieved by photo-initiated polymerization offers a feasible way to tune the mechanical property of hydrogel after injection, with an ideal mechanical adaptivity for clinical application. Remarkably, both in vitro and in vivo evaluations demonstrate that the hydrogel with endogenously bioactive galactoside units can promote cell spheroid formation and accelerate wound healing by expediting re-epithelialization, collagen deposition, angiogenesis as well as the formation of hair follicles.


Assuntos
Quitosana , Camundongos , Animais , Quitosana/farmacologia , Hidrogéis/farmacologia , Cicatrização , Glucanos/farmacologia
12.
IEEE Trans Med Imaging ; 42(6): 1735-1745, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37018671

RESUMO

Skin lesion segmentation from dermoscopy images is of great significance in the quantitative analysis of skin cancers, which is yet challenging even for dermatologists due to the inherent issues, i.e., considerable size, shape and color variation, and ambiguous boundaries. Recent vision transformers have shown promising performance in handling the variation through global context modeling. Still, they have not thoroughly solved the problem of ambiguous boundaries as they ignore the complementary usage of the boundary knowledge and global contexts. In this paper, we propose a novel cross-scale boundary-aware transformer, XBound-Former, to simultaneously address the variation and boundary problems of skin lesion segmentation. XBound-Former is a purely attention-based network and catches boundary knowledge via three specially designed learners. First, we propose an implicit boundary learner (im-Bound) to constrain the network attention on the points with noticeable boundary variation, enhancing the local context modeling while maintaining the global context. Second, we propose an explicit boundary learner (ex-Bound) to extract the boundary knowledge at multiple scales and convert it into embeddings explicitly. Third, based on the learned multi-scale boundary embeddings, we propose a cross-scale boundary learner (X-Bound) to simultaneously address the problem of ambiguous and multi-scale boundaries by using learned boundary embedding from one scale to guide the boundary-aware attention on the other scales. We evaluate the model on two skin lesion datasets and one polyp lesion dataset, where our model consistently outperforms other convolution- and transformer-based models, especially on the boundary-wise metrics. All resources could be found in https://github.com/jcwang123/xboundformer.


Assuntos
Neoplasias Cutâneas , Humanos , Neoplasias Cutâneas/diagnóstico por imagem , Processamento de Imagem Assistida por Computador
13.
Glob Chall ; 7(3): 2200154, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36910469

RESUMO

2D nanostructured materials have been applied for water purification in the past decades due to their excellent separation and adsorption performance. However, the functional 2D nanostructured molybdenum trioxide (MoO3)has rarely been reported for the removal of dyes. Here, functionalized MoO3 (F-MoO3) nanosheets are successfully fabricated with a high specific surface area (106 cc g-1) by a one-step mechanochemical exfoliation method as a highly effective adsorbent for removing dyes from water. According to the Raman, X-ray photoelectron spectroscopy, Fourier transform infrared (FTIR), and selected area electron diffraction analysis, functional groups (hdroxyl groups, amide groups, amine groups and amino groups) are identified in the as-prepared F-MoO3 nanosheets. The attached functional groups not only facilitate the dispersal ability of F-MoO3 nanosheets but also enhance the adsorption capacities. Thus, the performance (up to 556 mg g-1 when the initial concentration of Rhodamine B solution is 100 mg L-1) of as-prepared F-MoO3 nanosheets is almost two times higher than other reported MoO3 materials. Furthermore, the FTIR spectra, isotherm, and several factors (e.g., adsorbent dosage and adsorbate dosage) are also systematically investigated to explore the adsorption mechanism. Therefore, this work demonstrates that the F-MoO3 nanosheets are a promising candidate for wastewater treatment.

14.
Oncogene ; 42(18): 1419-1437, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36922677

RESUMO

Aberrant expression of XIST, a long noncoding RNA (lncRNA) initiating X chromosome inactivation (XCI) in early embryogenesis, is a common feature of breast cancer (BC). However, the roles of post-XCI XIST in breast carcinogenesis remain elusive. Here we identify XIST as a key regulator of breast cancer stem cells (CSCs), which exhibit aldehyde dehydrogenase positive (ALDH+) epithelial- (E) and CD24loCD44hi mesenchymal-like (M) phenotypes. XIST is variably expressed across the spectrum of BC subtypes, and doxycycline (DOX)-inducible knockdown (KD) of XIST markedly inhibits spheroid/colony forming capacity, tumor growth and tumor-initiating potential. This phenotype is attributed to impaired E-CSC in luminal and E- and M-CSC activities in triple-negative (TN) BC. Gene expression profiling unveils that XIST KD most significantly affects cytokine-cytokine receptor interactions, leading to markedly suppressed expression of proinflammatory cytokines IL-6 and IL-8 in ALDH- bulk BC cells. Exogenous IL-6, but not IL-8, rescues the reduced sphere-forming capacity and proportion of ALDH+ E-CSCs in luminal and TN BC upon XIST KD. XIST functions as a nuclear sponge for microRNA let-7a-2-3p to activate IL-6 production from ALDH- bulk BC cells, which acts in a paracrine fashion on ALDH+ E-CSCs that display elevated cell surface IL-6 receptor (IL6R) expression. This promotes CSC self-renewal via STAT3 activation and expression of key CSC factors including c-MYC, KLF4 and SOX9. Together, this study supports a novel role of XIST by derepressing let-7 controlled paracrine IL-6 proinflammatory signaling to promote CSC self-renewal.


Assuntos
Neoplasias da Mama , RNA Longo não Codificante , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Interleucina-6/metabolismo , Transdução de Sinais , Fenótipo , Neoplasias de Mama Triplo Negativas/patologia , Aldeído Desidrogenase/genética , Aldeído Desidrogenase/metabolismo , Células-Tronco Neoplásicas/patologia , Linhagem Celular Tumoral , Neoplasias da Mama/patologia , Fator de Transcrição STAT3/metabolismo
15.
Small ; 19(19): e2204898, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36581491

RESUMO

Two-dimensional (2D) transition metal dichalcogenides and graphene have revealed promising applications in optoelectronic and energy storage and conversion. However, there are rare reports of modifying the light-to-heat transformation via preparing their heterostructures for solar steam generation. In this work, commercial WS2 and sucrose are utilized as precursors to produce 2D WS2 -O-doped-graphene heterostructures (WS2 -O-graphene) for solar water evaporation. The WS2 -O-graphene evaporators demonstrate excellent average water evaporation rate (2.11 kg m-2  h-1 ) and energy efficiency (82.2%), which are 1.3- and 1.2-fold higher than WS2 and O-doped graphene-based evaporators, respectively. Furthermore, for the real seawater with different pH values (pH 1 and 12) and rhodamine B pollutants, the WS2 -O-graphene evaporators show great average evaporation rates (≈2.08 and 2.09 kg m-2  h-1 , respectively) for producing freshwater with an extremely low-grade of dye residual and nearly neutral pH values. More interestingly, due to the self-storage water ability of WS2 -O-graphene evaporators, water evaporation can be implemented without the presence of bulk water. As a result, the evaporation rate reaches 3.23 kg m-2  h-1 , which is ≈1.5 times higher than the regular solar water evaporation system. This work provides a new approach for preparing 2D transition metal dichalcogenides and graphene heterostructures for efficient solar water evaporation.

16.
China Tropical Medicine ; (12): 631-2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-979778

RESUMO

@#Abstract: Objective To understand the pollution characteristics and sources of PM2.5 in the atmosphere during heating and non-heating periods in Urumqi City in 2021, and provide scientific basis for pollution control during different periods. Method A total of 188 air samples were collected from area A and area B of Urumqi City, and 12 metal elements and 5 water-soluble ions were quantitatively analyzed, and the pollution sources were analyzed by enrichment factor method and principal component analysis method. Results In 2021, the mass concentrations of PM2.5 in areas A and B of Urumqi were 45.0 (20.0, 158) µg/m3 and 28.0 (17.5, 66.0) µg/m3, respectively, with statistically significant difference (Z=-2.870, P<0.05). During the heating period, the concentrations were 110 (68.0, 250) µg/m3 and 61.0 (31.0, 88.0) µg/m3, respectively, with no statistically significant difference (Z=-3.822, P<0.01). During the non-heating period, the concentrations were 18.0 (13.0, 22.3) µg/m3 and 18.0 (12.8, 22.0) µg/m3, respectively, with no statistically significant difference (Z=-0.596, P>0.05). The SNA (the sum of SO42-, NO3-and NH4+) accounted for 71.7% and 23.4% of PM2.5 in A area during heating and non-heating periods, respectively, with statistically significant difference (Z=-8.057, P<0.01); the corresponding proportions in B area were 60.7% and 24.9%, with statistically significant difference (Z=-6.672, P<0.01). During the heating and non-heating periods, the ratios of NO3-/SO42-are 0.63 and 0.54 in A area were 0.63 and 0.54, respectively, with statistically significant difference (Z=-2.382, P<0.05); and the corresponding ratios in B area were 0.72 and 0.53, respectively, with statistically significant difference (Z=-3.182, P<0.05). The ratio of NO3- to SO42- was less than 1 in both heating and non-heating periods in the two areas. and the correlation between five water-soluble ions was significant (P<0.05). The correlation coefficient between NH4+ and SO42-, NO3-and Cl- in A and B areas during heating periods were all >0.9, indicating that NH4+and SO42-, NO3- and Cl- bind in (NH4)2SO4, NH4HSO4, NH4NO3, and NH4Cl. During non-heating periods, the correlation between NH4+ and each ion was slightly lower. During heating periods in area A, Sb, As, Cd, Pb, and Tl were severely enriched (EF>100). During non-heating periods in the same area, As, Cd, Pb, Tl, and Hg were severely enriched (EF>100). During heating periods in area B, Sb, As, Cd, Pb, and Hg were severely enriched (EF>100), and during non-heating periods in the same area, Sb, Cd, and Hg were severely enriched (EF>100). Coal emission, photochemical secondary pollution, motor vehicle exhaust, dust and industrial pollution were the main sources of PM2.5 pollution in the two areas, and the contribution rate of fixed sources was higher than that of mobile sources. Conclusion In 2021, the mass concentration of PM2.5, water-soluble ions and metal elements in Urumqi City were higher in area A than area B, the heating period was higher than the non-heating period, the excess rate of area A was higher than that in area B, and the contribution rate of fixed air pollution was greater than that of mobile sources.

17.
Chin Med J (Engl) ; 135(18): 2218-2231, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36113844

RESUMO

BACKGROUND: Aurora kinases (AURKs) family plays a vital role not only in cell division but also in tumorigenesis. However, there are still rare systematic analyses of the diverse expression patterns and prognostic value of the AURKs family in breast cancer (BC). Systematic bioinformatics analysis was conducted to explore the biological role, prognostic value, and immunologic function of AURKs family in BC. METHODS: The expression, prognostic value, and clinical functions of AURKs family in BC were evaluated with several bioinformatics web portals: ONCOMINE Gene Expression Profiling Interactive Analysis, Kaplan-Meier plotter, cBioPortal, Metascape, GeneMANIA, and LinkedOmics; and the result was verified using human tissues. RESULTS: The expression of AURKA and AURKB were upregulated in BC in subgroup analyses based on tumor stage (all P   <  0.05). BC patients with high AURKA and AURKB expression had a worse overall survival, relapse-free survival, and distant metastasis-free survival (all P   <  0.05). Verification experiment revealed that AURKA and AURKB were upregulated in BC ( P  < 0.05). AURKA and AURKB were specifically associated with several tumor-associated kinases (polo-like kinase 1 and cyclin-dependent kinase 1), miRNAs (miR-507 and miR-381), and E2F transcription factor 1. Moreover, AURKA and AURKB were correlated with immune cell infiltration. Functional enrichment analysis revealed that AURKA and AURKB were involved in the cell cycle signaling pathway, platinum drug resistance signaling pathway, ErbB signaling pathway, Hippo signaling pathway, and nucleotide-binding and oligomerization domain-like receptor signaling pathway. CONCLUSIONS: Aurora kinases AURKA and AURKB could be employed as novel prognostic biomarkers or promising therapeutic targets for BC.


Assuntos
Neoplasias da Mama , MicroRNAs , Humanos , Feminino , Aurora Quinase A/genética , Aurora Quinase A/metabolismo , Aurora Quinase B/genética , Aurora Quinase B/metabolismo , Prognóstico , Neoplasias da Mama/genética , Recidiva Local de Neoplasia
18.
ChemSusChem ; 15(19): e202200933, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-35853838

RESUMO

Inadequate mass transportation of semipermeable membranes causes poor osmotic energy conversion from salinity-gradient. Here, the lamellar graphene oxide membranes (GOMs) constructed with numerous fusiform-like nanochannels, that are pre-filled with negatively charged polyanion electrolytes, to both enhance the ion permeability and ion selectivity of the membrane for energy harvest from the salinty gradient, were developed. The as-prepared membrane achieved the maximum output power density of ∼4.94 W m-2 under a 50 fold salinity gradient, which is 3.5 fold higher than that of pristine GOM. The enhancement could be ascribed to the synergistic impact of the expanded nanochannels and the enhanced space charge density. Via feeding with the artificial salinity water and monovalent cation electrolytes, the system could realise the power output up to 14.7 W m-2 and 34.1 W m-2 , respectively. Overall, this material design strategy could provide an alternative concept to effectively enhance ion transport of other two-dimensional (2D) membranes for specific purposes.


Assuntos
Membranas Artificiais , Salinidade , Cátions Monovalentes , Osmose , Água
19.
Biomed Pharmacother ; 153: 113387, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35834991

RESUMO

BACKGROUND: Although therapeutic antibodies against immune checkpoints such as PD-1/PD-L1 have achieved unprecedented success in clinical tumor patients, there are still many patients who are ineffective or have limited responses to immune checkpoint blockade (ICB). Discovery of novel strategies for cancer immunotherapy including natural small molecules is needed. METHODS: Owing to its extremely low content in Epimedium genus, we firstly constructed a microbial cell factory to enzymatically biosynthesize icariside I, a natural flavonoid monosaccharide from Herbal Epimedium. Using a combination of targeted MS-based metabolomics, flow cytometric analysis, and biological assays, the therapeutic potentials of icariside I were subsequently investigated in vivo and in vitro. RESULTS: We find that icariside I markedly downregulates a series of intermediate metabolites such as kynurenine, kynurenic acid and xanthurenic acid and corresponding key enzymes involved in kynurenine-AhR pathway in both tumor cells and tumor-bearing mice. In vivo, oral administration of icariside I downregulates SLC7A8 and PAT4 transporters and AhR, thus inhibiting nuclear PD-1 in CTLs. Moreover, icariside I significantly upregulates CD8 + T cells in both peripheral blood and tumor tissues of tumor-bearing mice. Consequently, interferon-γ (IFN-γ) secreted by CD8 + T cells suppresses tumor growth through activation of JAK1-STAT1 signaling, thus inducing tumor cell apoptosis. CONCLUSIONS: These results suggest that icariside I could be an effective small molecule drug for tumor immunotherapy by blocking kynurenine-AhR pathway and tumor immune escape.


Assuntos
Cinurenina , Neoplasias , Animais , Linhagem Celular Tumoral , Flavonas , Imunoterapia , Camundongos , Neoplasias/patologia , Receptor de Morte Celular Programada 1/metabolismo , Evasão Tumoral , Microambiente Tumoral , Umbeliferonas
20.
Small ; 18(28): e2201770, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35694762

RESUMO

Higher-metal (HM) nitrides are a fascinating family of materials being increasingly researched due to their unique physical and chemical properties. However, few focus on investigating their application in a solar steam generation because the controllable and large-scale synthesis of these materials remains a significant challenge. Herein, it is reported that higher-metal molybdenum nitride nanosheets (HM-Mo5 N6 ) can be produced at the gram-scale using amine-functionalized MoS2 as precursor. The first-principles calculation confirms amine-functionalized MoS2 nanosheet effectively lengthens the bonds of MoS leading to a lower bond binding energy, promoting the formation of MoN bonds and production of HM-Mo5 N6 . Using this strategy, other HM nitride nanosheets, such as W2 N3 , Ta3 N5 , and Nb4 N5 , can also be synthesized. Specifically, under one simulated sunlight irradiation (1 kW m-2 ), the HM-Mo5 N6 nanosheets are heated to 80 °C within only ≈24 s (0.4 min), which is around 78 s faster than the MoS2 samples (102 s/1.7 min). More importantly, HM-Mo5 N6 nanosheets exhibit excellent solar evaporation rate (2.48 kg m-2  h-1 ) and efficiency (114.6%), which are 1.5 times higher than the solar devices of MoS2 /MF.

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