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1.
Adv Healthc Mater ; : e2400091, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38722148

RESUMO

The role of the biomechanical stimulation generated from soft tissue has not been well quantified or separated from the self-regulated hard tissue remodeling governed by Wolff's Law. Prosthodontic overdentures, commonly used to restore masticatory functions, can cause localized ischemia and inflammation as they often compress patients' oral mucosa and impede local circulation. This biomechanical stimulus in mucosa is found to accelerate the self-regulated residual ridge resorption (RRR), posing ongoing clinical challenges. Based on the dedicated long-term clinical datasets, we developed an in-silico framework with a combination of techniques, including advanced image post-processing, patient-specific finite element models and unsupervised machine learning Self-Organizing map algorithm, to identify the soft tissue induced residual ridge resorption and quantitatively elucidate the governing relationship between the RRR and hydrostatic pressure in mucosa. The proposed governing equation has not only enabled a predictive simulation for RRR as showcased in this study, providing a biomechanical basis for optimizing prosthodontic treatments, but also extended our understanding of the mechanobiological responses in the soft-hard tissue interfaces and the role in bone remodeling. This article is protected by copyright. All rights reserved.

2.
Oncogene ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38744953

RESUMO

Esophageal squamous cell carcinoma (ESCC) is a prevalent malignancy of the digestive system. Hypoxia is a crucial player in tumor ferroptosis resistance. However, the molecular mechanism of hypoxia-mediated ferroptosis resistance in ESCC remains unclear. Here, USP2 expression was decreased in ESCC cell lines subjected to hypoxia treatment and was lowly expressed in clinical ESCC specimens. Ubiquitin-specific protease 2 (USP2) depletion facilitated cell growth, which was blocked in USP2-overexpressing cells. Moreover, USP2 silencing enhanced the iron ion concentration and lipid peroxidation accumulation as well as suppressed ferroptosis, while upregulating USP2 promoted ferroptotic cell death in ESCC cells. Furthermore, knockout of USP2 in ESCC models discloses the essential role of USP2 in promoting ESCC tumorigenesis and inhibiting ferroptosis. In contrast, overexpression of USP2 contributes to antitumor effect and ferroptosis events in vivo. Specifically, USP2 stably bound to and suppressed the degradation of nuclear receptor coactivator 4 (NCOA4) by eliminating the Lys48-linked chain, which in turn triggered ferritinophagy and ferroptosis in ESCC cells. Our findings suggest that USP2 plays a crucial role in iron metabolism and ferroptosis and that the USP2/NCOA4 axis is a promising therapeutic target for the management of ESCC.

3.
Biomed Pharmacother ; 175: 116728, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38733772

RESUMO

Patients' expectations and beliefs regarding the potential benefits and harms of medical interventions may induce placebo and nocebo effects, and affect the response to pain therapies. In a randomized clinical trial, we examined the effect of placebo and nocebo expectations on pain relief and adverse events (AEs) in association with a topical treatment among 65 cancer survivors experiencing chronic musculoskeletal pain. Participants received either a 1% camphor-based topical pain patch or a placebo treatment for 14 days. We measured pain severity with the worst pain item of the Brief Pain Inventory (BPI) at baseline and 14 days and treatment expectations at baseline with validated expectation questionnaires. We found that high vs. low nocebo expectations decreased pain severity improvements by 2.5 points (95% confidence interval [CI] -3.8 to -1.2; p<0.001) on a 0-10 numeric rating scale of the BPI and pain response rate by 42.7% (95% CI 0.2-0.6; p<0.001) at day 14, irrespective of placebo expectation status or treatment arms. Patients with high vs. low nocebo expectations in the true arm reported 22.4% more unwanted AEs. High nocebo expectations were associated with increased AEs by 39.5% (odds ratio: 12.0, 95% CI 1.2, 145.5; p=0.029) and decreased pain response in the true arm vs. placebo. Our study demonstrated that nocebo expectations, rather than placebo expectations, elevate the risk of AEs and compromise the effect of topical pain interventions. The findings raise the possibility that nocebo expectations may worsen somatic symptoms through heightening central pain amplification and should be further investigated.

4.
J Ethnopharmacol ; : 118328, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38734391

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Jiegeng decoction (JGD), consisting of Glycyrrhizae Radix et Rhizoma and Platycodonis Radix at the ratio of 2:1, is a classical Chinese medicine prescription firstly recorded in "Treatise on Febrile Diseases". JGD has been extensively utilized to treat sore throat and lung diseases for thousands of years in China. However, the pharmacological effect and mechanism of JGD on acute pharyngitis (AP) remain unclear. AIM OF THE STUDY: Our research aimed to reveal the pharmacological effect of JGD on AP and its potential mechanisms. MATERIALS AND METHODS: The chemical components of JGD were analyzed based on the UPLC-MS analysis. The anti-inflammatory effect of JGD was evaluated by NO production using the Griess assay in RAW.246.7 cells. The mRNA expression of iNOS, IL-1ß, IL-10, TNF-α, IL-6 and MCP-1 was determined by qRT-PCR in vitro. A 15% ammonia-induced AP model was established. The histopathology, the inflammatory cytokines IL-6 and MCP-1 in serum and the apoptosis-related genes caspease-8 and caspease-3 were determined by H&E staining, ELISA and qRT-PCR, respectively. The expression levels of p-p65, p65, p-JNK, JNK, p-p38, p38, p-ERK1/2, ERK1/2, and COX2 were measured through western blotting. RESULTS: Nine compounds, including liquiritin, liquiritin apiosde, liquiritigenin, platycodin D, platycoside A, licorice saponin J2, licorice saponin G2, glycyrrhizic acid, and licochalcone A, were identified. JGD significantly inhibited NO production and regulated the mRNA expression levels of cytokines in LPS-stimulated RAW264.7 cells. The results of in vivo experiments confirmed that JGD ameliorated AP through improving the pathological state of pharyngeal tissue, decreasing the serum levels of IL-6 and MCP-1 and preventing the tissue mRNA expression of caspease-8 and caspease-3. Furthermore, JGD also inhibited the NF-κB and MAPK pathways in the AP model. CONCLUSIONS: This study suggested that JGD could alleviate AP through its anti-inflammation via NF-κB and MAPK pathways, which supported the traditional application of JGD for the treatment of throat diseases.

6.
PLoS One ; 19(5): e0301484, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38696398

RESUMO

BACKGROUND AND STUDY AIM: The klotho protein, a multifunctional protein, has been shown to be associated with a wide range of endocrine diseases and has been linked to thyroid tumourigenesis. However, the relationship between serum klotho levels and thyroid hormones remains poorly understood. This study aimed to explore the correlation between serum klotho levels and thyroid hormones. METHODS: Data was obtained from the NHANES cycles 2007-2008, 2009-2010, and 2011-2012. A total of 4674 participants were recruited for this study. Statistical analysis was using multiple linear regression analyses, and restricted cubic spline plots (RCS) to investigate the association between serum klotho levels and serum levels of thyroid hormones. RESULTS: In the unadjusted covariate model, ln(klotho) significantly positively correlated with tT3, tT4, fT3, tT4/fT4, and tT3/fT3 (all P<0.01) and negatively correlated with TSH, tT4/tT3, and fT4/fT3 (all P<0.05). Furthermore, tT3, tT4, fT3and tT3/fT3 (P < 0.05) were still significant in the adjusted model. And it is worth noting that there is an approximately L-shaped nonlinear relationship between ln(klotho) and fT3,tT3 with a cut-off point of 6.697 (P-non-linear < 0.05). The stratification analysis showed gender and iodine level differences in the relationship between serum Klotho levels and thyroid hormones. CONCLUSION: There is an L-shaped nonlinear relationship between ln(klotho) and fT3, tT3, suggesting that klotho could be involved in the physiological regulation of thyroid function.


Assuntos
Glucuronidase , Proteínas Klotho , Hormônios Tireóideos , Humanos , Masculino , Feminino , Glucuronidase/sangue , Estudos Transversais , Hormônios Tireóideos/sangue , Pessoa de Meia-Idade , Adulto , Idoso
7.
J Am Chem Soc ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38767283

RESUMO

Quinone-based electrodes using carbonyl redox reactions are promising candidates for aqueous energy storage due to their high theoretical specific capacity and high-rate performance. However, the proton storage manners and their influences on the electrochemical performance of quinone are still not clear. Herein, we reveal that proton storage could determine the products of the enol conversion and the electrochemical stability of the organic electrode. Specifically, the protons preferentially coordinated with the prototypical pyrene-4,5,9,10-tetraone (PTO) cathode, and increasing the proton concentration in the electrolyte can improve its working potentials and cycling stability by tailoring the enol conversion reaction. We also found that exploiting Al2(SO4)3 as a pH buffer can increase the energy density of the Zn||PTO batteries from 242.8 to 284.6 Wh kg-1. Our research has a guiding significance for emphasizing proton storage of organic electrodes based on enol conversion reactions and improving their electrochemical performance.

8.
iScience ; 27(6): 109821, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38770131

RESUMO

The cyclic AMP-responsive element-binding protein (CREB)-regulated transcription coactivator 2 (CRTC2) is a crucial regulator of hepatic lipid metabolism and gluconeogenesis and correlates with tumorigenesis. However, the mechanism through which CRTC2 regulates hepatocellular carcinoma (HCC) progression is largely unknown. Here, we found that increased CRTC2 expression predicted advanced tumor grade and stage, as well as worse prognosis in patients with HCC. DNA promoter hypomethylation led to higher CRTC2 expression in HCC. Functionally, CRTC2 contributed to HCC malignant phenotypes through the activated Wnt/ß-catenin pathway, which could be abrogated by the small-molecular inhibitor XAV-939. Moreover, Crtc2 facilitated tumor growth while concurrently downregulating the PD-L1/PD-1 axis, resulting in primary resistance to immunotherapy. In immunocompetent mice models of HCC, targeting Crtc2 in combination with anti-PD-1 therapy prominently suppressed tumor growth by synergistically enhancing responsiveness to immunotherapy. Collectively, targeting CRTC2 might be a promising therapeutic strategy to sensitize immunotherapy in HCC.

9.
Artigo em Inglês | MEDLINE | ID: mdl-38772043

RESUMO

Caries is a destructive condition caused by bacterial infection that affects the hard tissues of the teeth, significantly reducing the quality of life for individuals. Photothermal therapy (PTT) offers a noninvasive and painless treatment for caries, but the use of unsafe laser irradiance limits its application. To address this challenge, we prepared nanoparticles of silver ion-doped Prussian blue (AgPB), which was encased within cationic guar gum (CG) to form the antibacterial PTT hydrogel CG-AgPB with a photothermal conversion efficiency of 34.4%. When exposed to an 808 nm laser at a power density of 0.4 W/cm2, the hydrogel readily reached a temperature of over 50 °C in just 3 min, synchronized by the discharge of Ag+ ions from the interstitial sites of AgPB crystals, resulting in broad-spectrum and synergistic antibacterial activities (>99%) against individual oral pathogens (Streptococcus sanguinis, Streptococcus mutans, and Streptococcus sobrinus) and pathogen-induced biofilms. In vivo, CG-AgPB-mediated PTT demonstrated a capability to profoundly reduce the terminal number of cariogenic bacteria to below 1% in a rat model of caries. Given the outstanding biocompatibility, injectability, and flushability, this CG-AgPB hydrogel may hold promise as a next-generation oral hygiene adjunct for caries management in a clinical setting.

10.
Anal Chim Acta ; 1309: 342670, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38772663

RESUMO

BACKGROUND: Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is a powerful tool for microanalysis of solid materials. Nevertheless, one limitation of the method is the lack of well-characterized homogeneous reference materials (RMs), such as BaF2 crystal and BaCO3 ceramics samples, making direct quantification difficult. This work presents a novel Direct Ink Writing (DIW) method to produce RMs for microanalysis. The Mg, Cr, Fe, Co, Ni, Cu, Y, Mo, Pr, Gd, Dy, Ho, Er, Tm, Yb, and Lu solutions were gravimetrically doped into BaCO3 by mixing with the dispersant and then cured with DIW techniques. (94) RESULTS: BaCO3 powder was combined with a dopant analyte to produce a printable slurry, aided by the use of a dispersant and cellulose. The resulting mixture was then printed using DIW equipment. The retention rates of the doped elements were investigated by internal and external standard method, and the results showed that they were completely dispersed in the solid material. After further optimization, it was found that there was no significant heterogeneity among the printed samples. LA-ICP-MS was used to analyze printed samples, to evaluate micro-scale homogeneity. The mass concentration of the doped element was determined by ICP-MS, verify its move closer to nominal value. Compared with the traditional reference materials preparation methods, the DIW technology greatly increased the sample homogeneity and the accuracy of the desired concentration. (132) SIGNIFICANCE: As far as we know, there are few reports on the application of DIW method to prepare calibration standards. In brief, it is proved that the proposed method of preparing calibration standard by DIW technique to quantify analytes is valid and robust. This procedure provides great potential for LA-ICP-MS in-situ analysis in the field of well-prepared products, such as ceramic and crystal samples.(63).

11.
Inorg Chem ; 63(19): 8782-8790, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38691448

RESUMO

Potocatalytic hydrogen evolution represnets a promising way to achieve renewable energy sources. Dual heterojunctions with an inverse opal structure are proposed for addressing fundamental challenges (low surface area, inefficient light absorption, and poor charge separation) in photocatalytic water splitting. Inverse opal structure and Co3O4 were introduced to design and synthesize a ZnO/ZnS/Co3O4 (IO-ZnO/ZnS/Co3O4) photocatalyst. Morphology characterizations and photoelectric measurements reveal that the introduction of three-dimensional (3D) structures and dual heterojunctions improves light utilization efficiency and accelerates charge separation, greatly promoting photoelectric performance. The as-prepared IO-ZnO/ZnS/Co3O4 manifests superior photocurrent density (0.49 mA/cm2), which is 4 times higher than that of IO-ZnO/ZnS due to the existence of dual heterojunctions. The result is further confirmed by an enhanced H2 production rate (153.01 µmol/g/h) in pure water. Notably, excellent cycling stability is achieved in pure water because Co3O4 can rapidly capture photogenerated holes to inhibit severe photocorrosion of ZnO/ZnS. Therefore, this work presents a new insight into inhibiting photocorrosion of metal sulfides and promoting their photoelectric performance by combining 3D structures and dual heterojunctions.

12.
ACS Biomater Sci Eng ; 10(5): 2863-2879, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38696332

RESUMO

The present work describes a preclinical trial (in silico, in vivo and in vitro) protocol to assess the biomechanical performance and osteogenic capability of 3D-printed polymeric scaffolds implants used to repair partial defects in a sheep mandible. The protocol spans multiple steps of the medical device development pipeline, including initial concept design of the scaffold implant, digital twin in silico finite element modeling, manufacturing of the device prototype, in vivo device implantation, and in vitro laboratory mechanical testing. First, a patient-specific one-body scaffold implant used for reconstructing a critical-sized defect along the lower border of the sheep mandible ramus was designed using on computed-tomographic (CT) imagery and computer-aided design software. Next, the biomechanical performance of the implant was predicted numerically by simulating physiological load conditions in a digital twin in silico finite element model of the sheep mandible. This allowed for possible redesigning of the implant prior to commencing in vivo experimentation. Then, two types of polymeric biomaterials were used to manufacture the mandibular scaffold implants: poly ether ether ketone (PEEK) and poly ether ketone (PEK) printed with fused deposition modeling (FDM) and selective laser sintering (SLS), respectively. Then, after being implanted for 13 weeks in vivo, the implant and surrounding bone tissue was harvested and microCT scanned to visualize and quantify neo-tissue formation in the porous space of the scaffold. Finally, the implant and local bone tissue was assessed by in vitro laboratory mechanical testing to quantify the osteointegration. The protocol consists of six component procedures: (i) scaffold design and finite element analysis to predict its biomechanical response, (ii) scaffold fabrication with FDM and SLS 3D printing, (iii) surface treatment of the scaffold with plasma immersion ion implantation (PIII) techniques, (iv) ovine mandibular implantation, (v) postoperative sheep recovery, euthanasia, and harvesting of the scaffold and surrounding host bone, microCT scanning, and (vi) in vitro laboratory mechanical tests of the harvested scaffolds. The results of microCT imagery and 3-point mechanical bend testing demonstrate that PIII-SLS-PEK is a promising biomaterial for the manufacturing of scaffold implants to enhance the bone-scaffold contact and bone ingrowth in porous scaffold implants. MicroCT images of the harvested implant and surrounding bone tissue showed encouraging new bone growth at the scaffold-bone interface and inside the porous network of the lattice structure of the SLS-PEK scaffolds.


Assuntos
Materiais Biocompatíveis , Mandíbula , Alicerces Teciduais , Animais , Ovinos , Mandíbula/cirurgia , Mandíbula/diagnóstico por imagem , Alicerces Teciduais/química , Impressão Tridimensional , Análise de Elementos Finitos , Osteogênese
13.
JCI Insight ; 9(9)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38716726

RESUMO

Childhood-onset essential hypertension (COEH) is an uncommon form of hypertension that manifests in childhood or adolescence and, in the United States, disproportionately affects children of African ancestry. The etiology of COEH is unknown, but its childhood onset, low prevalence, high heritability, and skewed ancestral demography suggest the potential to identify rare genetic variation segregating in a Mendelian manner among affected individuals and thereby implicate genes important to disease pathogenesis. However, no COEH genes have been reported to date. Here, we identify recessive segregation of rare and putatively damaging missense variation in the spectrin domain of spectrin repeat containing nuclear envelope protein 1 (SYNE1), a cardiovascular candidate gene, in 3 of 16 families with early-onset COEH without an antecedent family history. By leveraging exome sequence data from an additional 48 COEH families, 1,700 in-house trios, and publicly available data sets, we demonstrate that compound heterozygous SYNE1 variation in these COEH individuals occurred more often than expected by chance and that this class of biallelic rare variation was significantly enriched among individuals of African genetic ancestry. Using in vitro shRNA knockdown of SYNE1, we show that reduced SYNE1 expression resulted in a substantial decrease in the elasticity of smooth muscle vascular cells that could be rescued by pharmacological inhibition of the downstream RhoA/Rho-associated protein kinase pathway. These results provide insights into the molecular genetics and underlying pathophysiology of COEH and suggest a role for precision therapeutics in the future.


Assuntos
Proteínas do Citoesqueleto , Hipertensão Essencial , Sequenciamento do Exoma , Proteínas do Tecido Nervoso , Adolescente , Criança , Feminino , Humanos , Masculino , Idade de Início , Proteínas do Citoesqueleto/genética , Hipertensão Essencial/genética , Exoma/genética , Predisposição Genética para Doença , Mutação de Sentido Incorreto/genética , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética , Linhagem , Proteína rhoA de Ligação ao GTP/genética , Estados Unidos/epidemiologia , Recém-Nascido , Lactente , Pré-Escolar , Adulto Jovem
14.
BMJ Open ; 14(5): e081940, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719309

RESUMO

OBJECTIVES: This study aimed to determine the potential profiles of self-psychological adjustment in patients with lung cancer undergoing chemotherapy, including sense of coherence (SOC) and positive cognitive emotion regulation (PCER). The relationship between these profiles with post-traumatic growth (PTG) and the relevant factors of self-psychological adjustment in different profiles was analysed. DESIGN: Cross-sectional study. SETTING: Patients with lung cancer undergoing chemotherapy in China. PARTICIPANTS: A total of 330 patients with lung cancer undergoing chemotherapy were recruited out of which 321 completed the questionnaires effectively. METHODS: Latent profile analysis was used to identify self-psychological adjustment classes based on the two subscales of the Sense of Coherence Scale and Cognitive Emotion Regulation Questionnaire. One-way analysis of variance and multinomial logistic regression were performed to examine the subgroup association with characteristics and PTG. RESULTS: Three latent profiles of self-psychological adjustment were identified: low level (54.5%), high SOC-low PCER (15.6%) and high PCER (29.9%). The results of univariate analysis showed a significant difference in PTG scores among different self-psychological adjustment subgroups (F=11.55, p<0.001). Patients in the high-PCER group were more likely living in urban areas (OR=2.41, 95% CI 1.17 to 4.97, p=0.02), and time since cancer diagnosis was ≥6 months and <1 year (OR=3.54, 95% CI 1.3 to 9.64, p<0.001). CONCLUSION: This study revealed that most patients with lung cancer undergoing chemotherapy belonged to the low-level group. Three profiles are associated with PTG. There were differences in characteristics between patients treated with chemotherapy for lung cancer in the high-PCER and low-PCER groups. Thus, these profiles provide useful information for developing targeted individualised interventions based on demographic characteristics that would assist PTG in patients with lung cancer undergoing chemotherapy.


Assuntos
Neoplasias Pulmonares , Crescimento Psicológico Pós-Traumático , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/psicologia , Masculino , Estudos Transversais , Feminino , Pessoa de Meia-Idade , China/epidemiologia , Idoso , Adaptação Psicológica , Senso de Coerência , Inquéritos e Questionários , Antineoplásicos/uso terapêutico , Antineoplásicos/efeitos adversos , Adulto , Ajustamento Emocional
15.
Light Sci Appl ; 13(1): 110, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724516

RESUMO

Entanglement plays a vital role in quantum information processing. Owing to its unique material properties, silicon carbide recently emerged as a promising candidate for the scalable implementation of advanced quantum information processing capabilities. To date, however, only entanglement of nuclear spins has been reported in silicon carbide, while an entangled photon source, whether it is based on bulk or chip-scale technologies, has remained elusive. Here, we report the demonstration of an entangled photon source in an integrated silicon carbide platform for the first time. Specifically, strongly correlated photon pairs are efficiently generated at the telecom C-band wavelength through implementing spontaneous four-wave mixing in a compact microring resonator in the 4H-silicon-carbide-on-insulator platform. The maximum coincidence-to-accidental ratio exceeds 600 at a pump power of 0.17 mW, corresponding to a pair generation rate of (9 ± 1) × 103 pairs/s. Energy-time entanglement is created and verified for such signal-idler photon pairs, with the two-photon interference fringes exhibiting a visibility larger than 99%. The heralded single-photon properties are also measured, with the heralded g(2)(0) on the order of 10-3, demonstrating the SiC platform as a prospective fully integrated, complementary metal-oxide-semiconductor compatible single-photon source for quantum applications.

16.
Mater Today Bio ; 26: 101078, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38765244

RESUMO

Electrospun nanofibers have been widely employed in bone tissue engineering for their ability to mimic the micro to nanometer scale network of the native bone extracellular matrix. However, the dense fibrous structure and limited mechanical support of these nanofibers pose challenges for the treatment of critical size bone defects. In this study, we propose a facile approach for creating a three-dimensional scaffold using interconnected electrospun nanofibers containing melatonin (Scaffold@MT). The hypothesis posited that the sponge-like Scaffold@MT could potentially enhance bone regeneration and angiogenesis by modulating mitochondrial energy metabolism. Melatonin-loaded gelatin and poly-lactic-acid nanofibers were fabricated using electrospinning, then fragmented into shorter fibers. The sponge-like Scaffold@MT was created through a process involving homogenization, low-temperature lyophilization, and chemical cross-linking, while maintaining the microstructure of the continuous nanofibers. The incorporation of short nanofibers led to a low release of melatonin and increased Young's modulus of the scaffold. Scaffold@MT demonstrated positive biocompatibility by promoting a 14.2 % increase in cell proliferation. In comparison to the control group, Scaffold@MT significantly enhanced matrix mineralization by 3.2-fold and upregulated the gene expression of osteoblast-specific markers, thereby facilitating osteogenic differentiation of bone marrow mesenchymal stem cells (BMMSCs). Significantly, Scaffold@MT led to a marked enhancement in the mitochondrial energy function of BMMSCs, evidenced by elevated adenosine triphosphate (ATP) production, mitochondrial membrane potential, and protein expression of respiratory chain factors. Furthermore, Scaffold@MT promoted the migration of human umbilical vein endothelial cells (HUVECs) and increased tube formation by 1.3 times compared to the control group, accompanied by an increase in vascular endothelial growth factor (VEGFA) expression. The results of in vivo experiments indicate that the implantation of Scaffold@MT significantly improved vascularized bone regeneration in a distal femur defect in rats. Micro-computed tomography analysis conducted 8 weeks post-surgery revealed that Scaffold@MT led to optimal development of new bone microarchitecture. Histological and immunohistochemical analyses demonstrated that Scaffold@MT facilitated bone matrix deposition and new blood vessel formation at the defect site. Overall, the utilization of melatonin-loaded nanofiber sponges exhibits significant promise as a scaffold that promotes bone growth and angiogenesis, making it a viable option for the repair of critical-sized bone defects.

17.
Nat Mater ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769206

RESUMO

Structurally ordered L10-PtM (M = Fe, Co, Ni and so on) intermetallic nanocrystals, benefiting from the chemically ordered structure and higher stability, are one of the best electrocatalysts used for fuel cells. However, their practical development is greatly plagued by the challenge that the high-temperature (>600 °C) annealing treatment necessary for realizing the ordered structure usually leads to severe particle sintering, morphology change and low ordering degree, which makes it very difficult for the gram-scale preparation of desirable PtM intermetallic nanocrystals with high Pt content for practical fuel cell applications. Here we report a new concept involving the low-melting-point-metal (M' = Sn, Ga, In)-induced bond strength weakening strategy to reduce Ea and promote the ordering process of PtM (M = Ni, Co, Fe, Cu and Zn) alloy catalysts for a higher ordering degree. We demonstrate that the introduction of M' can reduce the ordering temperature to extremely low temperatures (≤450 °C) and thus enable the preparation of high-Pt-content (≥40 wt%) L10-Pt-M-M' intermetallic nanocrystals as well as ten-gram-scale production. X-ray spectroscopy studies, in situ electron microscopy and theoretical calculations reveal the fundamental mechanism of the Sn-facilitated ordering process at low temperatures, which involves weakened bond strength and consequently reduced Ea via Sn doping, the formation and fast diffusion of low-coordinated surface free atoms, and subsequent L10 nucleation. The developed L10-Ga-PtNi/C catalysts display outstanding performance in H2-air fuel cells under both light- and heavy-duty vehicle conditions. Under the latter condition, the 40% L10-Pt50Ni35Ga15/C catalyst delivers a high current density of 1.67 A cm-2 at 0.7 V and retains 80% of the current density after extended 90,000 cycles, which exceeds the United States Department of Energy performance metrics and represents among the best cathodic electrocatalysts for practical proton-exchange membrane fuel cells.

18.
Anal Chem ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771107

RESUMO

Illegal addition of drugs is common but seriously threatens public health safety. Conventional mass spectrometry methods are difficult to realize direct analysis of drugs existing in some complex matrices such as seawater or soil due to the ion suppression effect and contamination to MS parts caused by nonvolatile salts. In this work, a novel crystallization and solvent evaporation ionization mass spectrometry (CSEI-MS) method was constructed and developed to achieve rapid desalting detection. CSEI only consists of a heated plate and a nebulizer and exhibits excellent desalting performance, enabling direct analysis of six drugs dissolved in eight kinds of salt solutions (up to 200 mmol/L) and three complex salty matrices. Under optimized conditions, CSEI-MS presents high sensitivity, accuracy, linearity, and intraday and interday precision. Finally, this method is applied to the quantitative analysis of drugs in seawater, hand cream, and soil. Furthermore, the highly sensitive detection of CSEI-MS is demonstrated to remain even if the detection processes are conducted within 5 s via common commercial tools.

19.
Sci Rep ; 14(1): 11050, 2024 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745054

RESUMO

Phosphorus (P) is a crucial macronutrient for plant growth and development. Basic metabolic processes regulate growth; however, the molecular detail of these pathways under low phosphorous (LP) in wheat is still unclear. This study aims to elucidate the varied regulatory pathways responses to LP stress in wheat genotypes. Phenotypic, physiological, and transcriptome analyses were conducted on Fielder (P efficient) and Ardito (P inefficient) wheat genotypes after four days of normal phosphorous (NP) and LP stress. In response to LP, Fielder outperformed Ardito, displaying higher chlorophyll content-SPAD values (13%), plant height (45%), stem diameter (12%), shoot dry weight (42%), and root biomass (75%). Root structure analysis revealed that Fielder had greater total root length (50%), surface area (56%), volume (15%), and diameter (4%) than Ardito under LP. These findings highlight Fielder's superior performance and adaptation to LP stress. Transcriptome analysis of wheat genotype roots identified 3029 differentially expressed genes (DEGs) in Fielder and 1430 in Ardito, highlighting LP-induced changes. Key DEGs include acid phosphatases (PAPs), phosphate transporters (PHT1 and PHO1), SPX, and transcription factors (MYB, bHLH, and WRKY). KEGG enrichment analysis revealed key pathways like plant hormones signal transduction, biosynthesis of secondary metabolites, and carbohydrate biosynthesis metabolism. This study unveils crucial genes and the intricate regulatory process in wheat's response to LP stress, offering genetic insights for enhancing plant P utilization efficiency.


Assuntos
Adaptação Fisiológica , Regulação da Expressão Gênica de Plantas , Fósforo , Raízes de Plantas , Transcriptoma , Triticum , Triticum/genética , Triticum/metabolismo , Triticum/crescimento & desenvolvimento , Fósforo/deficiência , Fósforo/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Adaptação Fisiológica/genética , Estresse Fisiológico/genética , Perfilação da Expressão Gênica , Genótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fenótipo
20.
Cancer Lett ; 593: 216935, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38704136

RESUMO

Hepatocellular carcinoma (HCC) is a prevalent malignancy characterized by complex heterogeneity and drug resistance. Resistance to ferroptosis is closely related to the progression of HCC. While HCC tumors vary in their sensitivity to ferroptosis, the precise factors underlying this heterogeneity remain unclear. In this study, we sought to elucidate the mechanisms that contribute to ferroptosis resistance in HCC. Whole-genome CRISPR/Cas9 screen using a subtoxic concentration (IC20) of ferroptosis inducer erastin in the HCC cell line Huh7 revealed TRIM34 as a critical driver of ferroptosis resistance in HCC. Further investigation revealed that TRIM34 suppresses ferroptosis in HCC cells, promoting their proliferation, migration, and invasion both in vitro and in vivo. Furthermore, TRIM34 expression is elevated in HCC tumor tissues, correlating with a poor prognosis. Mechanistically, TRIM34 directly interacts with Up-frameshift 1 (UPF1), a core component of the nonsense-mediated mRNA decay (NMD) pathway, to promote its ubiquitination and degradation. This interaction suppresses GPX4 transcript degradation, thus promoting the protein levels of this critical ferroptosis suppressor in HCC. In light of the close crosstalk between ferroptosis and the adaptive immune response in cancer, HCC cells with targeting knockdown of TRIM34 exhibited an improved response to anti-PD-1 treatment. Taken together, the TRIM34/UPF1/GPX4 axis mediates ferroptosis resistance in HCC, thereby promoting malignant phenotypes. Targeting TRIM34 may thus represent a promising new strategy for HCC treatment.

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