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1.
Diabetol Metab Syndr ; 16(1): 98, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38715117

RESUMO

BACKGROUND: Emerging evidence indicates carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is involved in the development of atherosclerosis (AS). However, the roles and functions of CEACAM1 in AS remain unknown. Therefore, this study aims to investigate the roles and molecular functions of CEACAM1 in AS. METHODS: We constructed a diabetes mellitus (DM) + high-fat diet (HFD) mouse model based on the streptozotocin (STZ)-induced apolipoprotein E-knockdown (ApopE-/-) mouse to investigate the roles and regulatory mechanism of miR-449a/CEACAM1 axis. The mRNA expression and protein levels in this study were examined using quantity PCR, western blot, immunofluorescence (IF), enzyme-linked immunosorbent assay (ELISA), and immunohistochemistry (IHC), respectively. And the lipid deposition and collagen content were detected using Oil Red O and Sirius Red staining. Cell apoptosis, migration, invasion, and tuber formation were detected by Annexin-V FITC/PI, wound healing, transwell, and tuber formation assays, respectively. The relationship between miR-449a and CEACAM1 was determined by a dual-luciferase reporter gene assay. RESULTS: miR-449a and MMP-9 were upregulated, and CEACAM1 was downregulated in the DM + HFD MOUSE model. Upregulation of CEACAM1 promoted atherosclerotic plaque stability and inhibited inflammation in the DM + HFD mouse model. And miR-449a directly targeted CEACAM1. Besides, miR-449a interacted with CEACAM1 to regulate atherosclerotic plaque stability and inflammation in DM-associated AS mice. In vitro, the rescue experiments showed miR-449a interacted with CEACAM1 to affect apoptosis, migration, invasion, and tuber formation ability in high glucose (HG)-induced HUVECs. CONCLUSION: These results demonstrated that miR-449a promoted plaque instability and inflammation in DM and HFD-induced mice by targeting CEACAM1.

2.
Int J Nanomedicine ; 19: 4061-4079, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38736651

RESUMO

Purpose: Transdermal Drug Delivery System (TDDS) offers a promising alternative for delivering poorly soluble drugs, challenged by the stratum corneum's barrier effect, which restricts the pool of drug candidates suitable for TDDS. This study aims to establish a delivery platform specifically for highly lipophilic drugs requiring high doses (log P > 5, dose > 10 mg/kg/d), to improve their intradermal delivery and enhance solubility. Methods: Cannabidiol (CBD, log P = 5.91) served as the model drug. A CBD nanosuspension (CBD-NS) was prepared using a bottom-up method. The particle size, polydispersity index (PDI), zeta potential, and concentration of the CBD-NS were characterized. Subsequently, CBD-NS was incorporated into dissolving microneedles (DMNs) through a one-step manufacturing process. The intradermal dissolution abilities, physicochemical properties, mechanical strength, insertion depth, and release behavior of the DMNs were evaluated. Sprague-Dawley (SD) rats were utilized to assess the efficacy of the DMN patch in treating knee synovitis and to analyze its skin permeation kinetics and pharmacokinetic performance. Results: The CBD-NS, stabilized with Tween 80, exhibited a particle size of 166.83 ± 3.33 nm, a PDI of 0.21 ± 0.07, and a concentration of 46.11 ± 0.52 mg/mL. The DMN loaded with CBD-NS demonstrated favorable intradermal dissolution and mechanical properties. It effectively increased the delivery of CBD into the skin, extended the action's duration in vivo, and enhanced bioavailability. CBD-NS DMN exhibited superior therapeutic efficacy and safety in a rat model of knee synovitis, significantly inhibiting TNF-α and IL-1ß compared with the methotrexate subcutaneous injection method. Conclusion: NS technology effectively enhances the solubility of the poorly soluble drug CBD, while DMN facilitates penetration, extends the duration of action in vivo, and improves bioavailability. Furthermore, CBD has shown promising therapeutic outcomes in treating knee synovitis. This innovative drug delivery system is expected to offer a more efficient solution for the administration of highly lipophilic drugs akin to CBD, thereby facilitating high-dose administration.


Assuntos
Administração Cutânea , Canabidiol , Agulhas , Tamanho da Partícula , Ratos Sprague-Dawley , Absorção Cutânea , Suspensões , Animais , Canabidiol/farmacocinética , Canabidiol/administração & dosagem , Canabidiol/química , Absorção Cutânea/efeitos dos fármacos , Ratos , Suspensões/química , Masculino , Pele/metabolismo , Pele/efeitos dos fármacos , Solubilidade , Sistemas de Liberação de Medicamentos/métodos , Adesivo Transdérmico , Nanopartículas/química , Microinjeções/métodos , Microinjeções/instrumentação
3.
PLoS One ; 19(5): e0302780, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38713738

RESUMO

Reticulocalbin 1 (RCN1) is a calcium-binding protein involved in the regulation of calcium homeostasis in the endoplasmic reticulum. The aim of this study was to explore the clinical value and biological role of RCN1 in esophageal squamous cell carcinoma (ESCC). In addition, we investigated the effect of RCN1 on the polarization of tumor-associated macrophages (TAMs). The GSE53625 dataset from the Gene Expression Omnibus database was used to analyze the expression of RCN1 mRNA and its relationship with clinical value and immune cell infiltration. Immunohistochemistry was used to validate the expression of RCN1 and its correlation with clinicopathological characteristics. Subsequently, transwell and cell scratch assays were conducted to evaluate the migration and invasion abilities of ESCC cells. The expression levels of epithelial-mesenchymal transition (EMT)-related proteins were evaluated by western blot, while apoptosis was detected by flow cytometry and western blot. Additionally, qRT‒PCR was utilized to evaluate the role of RCN1 in macrophage polarization. RCN1 was significantly upregulated in ESCC tissues and was closely associated with lymphatic metastasis and a poor prognosis, and was an independent prognostic factor for ESCC in patients. Knockdown of RCN1 significantly inhibited the migration, invasion, and EMT of ESCC cells, and promoted cell apoptosis. In addition, RCN1 downregulation inhibited M2 polarization. RCN1 is upregulated in ESCC patients and is negatively correlated with patient prognosis. Knocking down RCN1 inhibits ESCC progression and M2 polarization. RCN1 can serve as a potential diagnostic and prognostic indicator for ESCC, and targeting RCN1 is a very promising therapeutic strategy.


Assuntos
Proteínas de Ligação ao Cálcio , Regulação para Baixo , Transição Epitelial-Mesenquimal , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Regulação Neoplásica da Expressão Gênica , Humanos , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Carcinoma de Células Escamosas do Esôfago/metabolismo , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Feminino , Masculino , Transição Epitelial-Mesenquimal/genética , Linhagem Celular Tumoral , Pessoa de Meia-Idade , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/genética , Movimento Celular/genética , Progressão da Doença , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/patologia , Apoptose , Prognóstico , Macrófagos/metabolismo
4.
Front Psychol ; 15: 1367308, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38716276

RESUMO

Purpose: The family residence structure serves as a crucial pathway through which the family environment influences adolescents' development. Methods: Drawing on nationally representative data, this study employs multiple linear regression models and propensity score matching to examine the impact of various family residence structures on adolescents' non-cognitive abilities. Causal identification is achieved through propensity score matching, while robustness is assessed using methods such as augmented inverse probability weighting and placebo tests. Heterogeneity analysis is conducted based on gender and household registration, aiming to explore the mechanisms by which family residence structure affects adolescents' non-cognitive abilities. Results: The findings indicate that compared to two-parent co-residence households, three-generation co-residence families have significantly positive effects on emotional stability, conscientiousness, and agreeableness among adolescents. In contrast, skip-generation coresidence families exhibit significant negative effects on emotional stability and agreeableness in adolescents. Further investigation into the underlying mechanisms reveals that parental involvement and family socioeconomic status within three-generation co-residence families positively influence adolescents' non-cognitive abilities. Conclusion: This study highlights the importance of considering grandparents' role in adolescent growth and advocates for policy recommendations focusing on enhancing non-cognitive abilities in adolescents from skip-generation co-residence families.

5.
Mol Divers ; 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38733433

RESUMO

The avidity of cancer cells for iron highlights the potential for iron chelators to be used in cancer therapy. Herein, we designed and synthesized a novel series of 5H-[1,2,4]triazino[5,6-b]indole derivatives bearing a pyridinocycloalkyl moiety using a ring-fusion strategy based on the structure of an iron chelator, VLX600. The antiproliferative activity evaluation against cancer cells and normal cells led to the identification of compound 3k, which displayed the strongest antiproliferative activity in vitro against A549, MCF-7, Hela and HepG-2 with IC50 values of 0.59, 0.86, 1.31 and 0.92 µM, respectively, and had lower cytotoxicity against HEK293 than VLX600. Further investigations revealed that unlike VLX600, compound 3k selectively bound to ferrous ions, but not to ferric ions, and addition of Fe2+ abolished the cytotoxicity of 3k. Flow cytometry assays demonstrated that 3k arrested the cell cycle at the G1 phase and induced significant apoptosis in A549 cells in dose and time-dependent manners, corresponding to JC-1 staining assay results. Western blot analysis of Bcl-2, Bax and cleaved caspase-3 proteins further provided evidences that induction of apoptosis by 3k in A549 cells might be at least via the mitochondria pathway. These above results highlight that 3k is a valuable lead compound that deserves further investigation as an iron chelator for the treatment of cancer.

6.
J Org Chem ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38738957

RESUMO

A visible-light-enabled photoredox radical cascade cyclization of 2-vinyl benzimidazole derivatives is developed. This chemistry is applicable to a wide range of N-aroyl 2-vinyl benzimidazoles as acceptors, and halo compounds, including alkyl halides, acyl chlorides and sulfonyl chlorides, as radical precursors. The Langlois reagent also serves as an effective partner in this photocatalytic oxidative cascade process. This protocol provides a robust alternative for rendering highly functionalized benzo[4,5]imidazo[1,2-b]isoquinolin-11(6H)-ones.

7.
iScience ; 27(5): 109659, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38706841

RESUMO

Abnormal mTORC1 activation by the lysosomal Ragulator complex has been implicated in cancer and glycolytic metabolism associated with drug resistance. Fasting upregulates RNF152 and mediates the metabolic status of cells. We report that RNF152 regulates mTORC1 signaling by targeting a Ragulator subunit, p18, and attenuates gemcitabine resistance in gallbladder cancer (GBC). We detected levels of RNF152 and p18 in tissues and undertook mechanistic studies using activators, inhibitors, and lentivirus transfections. RNF152 levels were significantly lower in GBC than in adjacent non-cancer tissues. Fasting impairs glycolysis, induces gemcitabine sensitivity, and upregulates RNF152 expression. RNF152 overexpression increases the sensitivity of GBC cells to gemcitabine, whereas silencing RNF152 has the opposite effect. Fasting-induced RNF152 ubiquitinates p18, resulting in proteasomal degradation. RNF152 deficiency increases the lysosomal localization of p18 and increases mTORC1 activity, to promote glycolysis and decrease gemcitabine sensitivity. RNF152 suppresses mTORC1 activity to inhibit glycolysis and enhance gemcitabine sensitivity in GBC.

8.
World J Gastrointest Surg ; 16(4): 1055-1065, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38690047

RESUMO

BACKGROUND: Colon cancer is one of the most common malignant tumors of the digestive system. Liver metastasis after colon cancer surgery is the primary cause of death in patients with colon cancer. AIM: To construct a novel nomogram model including various factors to predict liver metastasis after colon cancer surgery. METHODS: We retrospectively analyzed 242 patients with colon cancer who were admitted and underwent radical resection for colon cancer in Zhejiang Provincial People's Hospital from December 2019 to December 2022. Patients were divided into liver metastasis and non-liver metastasis groups. Sex, age, and other general and clinicopathological data (preoperative blood routine and biochemical test indexes) were compared. The risk factors for liver metastasis were analyzed using single-factor and multifactorial logistic regression. A predictive model was then constructed and evaluated for efficacy. RESULTS: Systemic inflammatory index (SII), C-reactive protein/albumin ratio (CAR), red blood cell distribution width (RDW), alanine aminotransferase, preoperative carcinoembryonic antigen level, and lymphatic metastasis were different between groups (P < 0.05). SII, CAR, and RDW were risk factors for liver metastasis after colon cancer surgery (P < 0.05). The area under the curve was 0.93 for the column-line diagram prediction model constructed based on these risk factors to distinguish whether liver metastasis occurred postoperatively. The actual curve of the column-line diagram predicting the risk of postoperative liver metastasis was close to the ideal curve, with good agreement. The prediction model curves in the decision curve analysis showed higher net benefits for a larger threshold range than those in extreme cases, indicating that the model is safer. CONCLUSION: Liver metastases after colorectal cancer surgery could be well predicted by a nomogram based on the SII, CAR, and RDW.

9.
J Cereb Blood Flow Metab ; : 271678X241251570, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700501

RESUMO

Perivascular spaces (PVSs) as the anatomical basis of the glymphatic system, are increasingly recognized as potential imaging biomarkers of neurological conditions. However, it is not clear whether enlarged PVSs are associated with alcohol-related brain damage (ARBD). We aimed to investigate the effect of long-term alcohol exposure on dyslipidemia and the glymphatic system in ARBD. We found that patients with ARBD exhibited significantly enlargement of PVSs in the frontal cortex and basal ganglia, as well as a notable increased levels of total cholesterol (TC) and triglycerides (TG). The anatomical changes of the glymphatic drainage system mentioned above were positively associated with TC and TG. To further explore whether enlarged PVSs affects the function of the glymphatic system in ARBD, we constructed long alcohol exposure and high fat diet mice models. The mouse model of long alcohol exposure exhibited increased levels of TC and TG, enlarged PVSs, the loss of aquaporin-4 polarity caused by reactive astrocytes and impaired glymphatic drainage function which ultimately caused cognitive deficits, in a similar way as high fat diet leading to impairment in glymphatic drainage. Our study highlights the contribution of dyslipidemia due to long-term alcohol abuse in the impairment of the glymphatic drainage system.

10.
Front Immunol ; 15: 1379586, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38745648

RESUMO

Objective: Choroidal neovascularization (CNV) represents the predominant form of advanced wet Age-related Macular Degeneration (wAMD). Macrophages play a pivotal role in the pathological progression of CNV. Meteorin-like (Metrnl), a novel cytokine known for its anti-inflammatory properties in macrophages, is the focus of our investigation into its mechanism of action and its potential to impede CNV progression. Methods: Cell viability was evaluated through CCK-8 and EdU assays following Metrnl treatment. Expression levels of inflammatory cytokines and proteins were assessed using quantitative reverse-transcription polymerase chain reaction(qRT-PCR), enzyme-linked immunosorbent assay (ELISA), and western blot techniques. Protein-protein interactions were identified through protein mass spectrometry and co-immunoprecipitation (Co-IP). Additionally, in vivo and in vitro neovascularization models were employed to evaluate angiogenesis. Results: Our results revealed downregulated Metrnl levels in the choroid-sclera complex of CNV mice, the aqueous humor of wAMD patients, and activated macrophages. Metrnl overexpression demonstrated a reduction in pro-inflammatory cytokine production, influenced endothelial cell function, and suppressed angiogenesis in choroid explants and CNV models. Through protein mass spectrometry and Co-IP, we confirmed Metrnl binds to UCHL-1 to modulate the NF-κB signaling pathway. This interaction inhibited the transcription and expression of pro-inflammatory cytokines, ultimately suppressing angiogenesis. Conclusion: In summary, our findings indicate that Metrnl down-regulates macrophage pro-inflammatory cytokine secretion via the UCHL-1/NF-κB signaling pathway. This mechanism alleviates the inflammatory microenvironment and effectively inhibits choroidal neovascularization.


Assuntos
Neovascularização de Coroide , NF-kappa B , Transdução de Sinais , Neovascularização de Coroide/metabolismo , Neovascularização de Coroide/patologia , Neovascularização de Coroide/genética , Animais , Camundongos , Humanos , NF-kappa B/metabolismo , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Macrófagos/metabolismo , Macrófagos/imunologia , Corioide/metabolismo , Corioide/patologia , Corioide/irrigação sanguínea , Masculino , Degeneração Macular Exsudativa/metabolismo , Degeneração Macular Exsudativa/genética , Degeneração Macular Exsudativa/patologia , Inflamação/metabolismo , Citocinas/metabolismo
11.
Biotechnol Lett ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607604

RESUMO

Biofuel production from lignocellulose feedstocks is sustainable and environmentally friendly. However, the lignocellulosic pretreatment could produce fermentation inhibitors causing multiple stresses and low yield. Therefore, the engineering construction of highly resistant microorganisms is greatly significant. In this study, a composite functional chimeric cellulosome equipped with laccase, versatile peroxidase, and lytic polysaccharide monooxygenase was riveted on the surface of Saccharomyces cerevisiae to construct a novel yeast strain YI/LVP for synergistic lignin degradation and cellulosic ethanol production. The assembly of cellulosome was assayed by immunofluorescence microscopy and flow cytometry. During the whole process of fermentation, the maximum ethanol concentration and cellulose conversion of engineering strain YI/LVP reached 8.68 g/L and 83.41%, respectively. The results proved the availability of artificial chimeric cellulosome containing lignin-degradation enzymes for cellulosic ethanol production. The purpose of the study was to improve the inhibitor tolerance and fermentation performance of S. cerevisiae through the construction and optimization of a synergistic lignin-degrading enzyme system based on cellulosome.

13.
ACS Med Chem Lett ; 15(4): 518-523, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38628793

RESUMO

Small-molecule inhibitors targeting programmed cell death-1/programmed cell death-ligand 1 (PD-1/PD-L1) interactions can compensate for the shortcomings of antibody-based inhibitors and have attracted considerable attention, some of which have already entered clinical trials. Herein, based on our previous study on small-molecule PD-L1 inhibitors, we reported a series of 8-(o-tolyl)quinazoline derivatives by the skeleton merging strategy. Homogenous time-resolved fluorescence (HTRF) assay against PD-1/PD-L1 interaction identified compound A5, which showed the most potent inhibition with an IC50 value of 23.78 nM. Meanwhile, based on the results of HTRF assay, the structure-activity relationships (SARs) of the tail were focused on. Cell-based PD-1/PD-L1 blockade assay further revealed that A5 significantly blocked the PD-1/PD-L1 interaction at 1.1 µM in the co-culture system of Jurkat-NFAT-PD-1 cells and Hep3B-OS8-hPD-L1 cells with no significant cytotoxicity on Jurkat cells. Moreover, the proposed binding mode of A5 was investigated by a docking analysis. These results indicate that compound A5 is a promising lead compound that deserves further investigation.

14.
IEEE Comput Graph Appl ; PP2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630562

RESUMO

Caricature generation aims to translate portrait photos into caricatures with exaggerated and hand-drawn artistic styles. Previous methods faced challenges in creating diverse and meaningful exaggeration effects, yielding unsatisfactory and uncontrollable results. To overcome this, we proposed ETCari, a novel weakly supervised exaggeration transfer network. ETCari enables the learning of diverse exaggeration caricature styles from various artists, better meeting individual customization requirements and achieving diversified exaggeration while retaining identity features. Specifically, we use the thin-plate spline control point deformation field as the ground truth, serving as the loss for weakly supervised learning to address the challenge of no labels. We convert input to an intermediate modality for domain adaptation, training a teacher model. Subsequently, we perform cross-modal knowledge distillation to train the student model, simplifying preprocessing during inference and avoiding the impact of face parser errors. Experiments on the WebCaricature dataset demonstrate that ETCari effectively performs exaggeration transfer, generating appealing caricatures.

15.
J Extracell Vesicles ; 13(4): e12429, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38576241

RESUMO

Osteoporosis (OP) is a systematic bone disease characterized by low bone mass and fragile bone microarchitecture. Conventional treatment for OP has limited efficacy and long-term toxicity. Synthetic biology makes bacterial extracellular vesicle (BEVs)-based therapeutic strategies a promising alternative for the treatment of OP. Here, we constructed a recombinant probiotics Escherichia coli Nissle 1917-pET28a-ClyA-BMP-2-CXCR4 (ECN-pClyA-BMP-2-CXCR4), in which BMP-2 and CXCR4 were overexpressed in fusion with BEVs surface protein ClyA. Subsequently, we isolated engineered BEVs-BMP-2-CXCR4 (BEVs-BC) for OP therapy. The engineered BEVs-BC exhibited great bone targeting in vivo. In addition, BEVs-BC had good biocompatibility and remarkable ability to promote osteogenic differentiation of BMSCs. Finally, the synthetic biology-based BEVs-BC significantly prevented the OP in an ovariectomized (OVX) mouse model. In conclusion, we constructed BEVs-BC with both bone-targeting and bone-forming in one-step using synthetic biology, which provides an effective strategy for OP and has great potential for industrialization.


Assuntos
Vesículas Extracelulares , Osteoporose , Animais , Camundongos , Vesículas Extracelulares/metabolismo , Osteogênese , Osteoporose/terapia , Transdução de Sinais , Biologia Sintética
16.
Artigo em Inglês | MEDLINE | ID: mdl-38621188

RESUMO

We thoroughly investigated the anharmonic lattice dynamics and microscopic mechanisms of the thermal and electronic transport characteristics in orthorhombic o-CsCu5S3 at the atomic level. Taking into account the phonon energy shifts and the wave-like tunneling phonon channel, we predict an ultralow κL of 0.42 w/mK at 300 K with an extremely weak temperature dependence following ∼T-0.33. These findings agree well with experimental values along with the parallel to the Bridgman growth direction. The κL in o-CsCu5S3 is suppressed down to the amorphous limit, primarily due to the unconventional Cu-S bonding induced by the p-d hybridization antibonding state coupled with the stochastic oscillation of Cs atoms. The nonstandard temperature dependence of κL can be traced back to the critical or dominant role of wave-like tunneling of phonon contributions in thermal transport. Moreover, the p-d hybridization of Cu(3)-S bonding results in the formation of a valence band with "pudding-mold" and high-degeneracy valleys, ensuring highly efficient electron transport characteristics. By properly adjusting the carrier concentration, excellent thermoelectric performance is achieved with a maximum thermoelectric conversion efficiency of 18.4% observed at 800 K in p-type o-CsCu5S3. Our work not only elucidates the anomalous electronic and thermal transport behavior in the copper-based chalcogenide o-CsCu5S3 but also provides insights for manipulating its thermal and electronic properties for potential thermoelectric applications.

17.
Med Biol Eng Comput ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38622437

RESUMO

Mandibular defect repair has always been a clinical challenge, facing technical bottleneck. The new materials directly affect technological breakthroughs in mandibular defect repair field. Our aim is to fabricate a scaffold of advanced biomaterials for repairing of small mandibular defect. Therefore, a novel dual-channel scaffold consisting of silk fibroin/collagen type-I/hydroxyapatite (SCH) and polycaprolactone/hydroxyapatite (PCL/HA) was fabricated by cryogenic 3D printing technology with double nozzles. The mechanical properties and behaviors of the dual-channel scaffold were investigated by performing uniaxial compression, creep, stress relaxation, and ratcheting experiments respectively. The experiments indicated that the dual-channel scaffold was typical non-linear viscoelastic consistent with cancellous tissue; the Young's modulus of this scaffold was 60.1 kPa. Finite element analysis (FEA) was employed performing a numerical simulation to evaluate the implantation effect in mandible. The stress distribution of the contact area between scaffold and defect was uniform, the maximum Mises stress of cortical bone and cancellous bone in defect area were 54.520 MPa and 3.196 MPa, and the maximum displacement of cortical bone and cancellous bone in defect area were 0.1575 mm and 0.1555 mm respectively, which distributed in the incisor region. The peak maximum Mises stress experienced by the implanted scaffold was 3.128 × 10-3 MPa, and the maximum displacement was 6.453 × 10-2 mm distributed near incisor area. The displacement distribution of the scaffold was consistent with that of cortical and cancellous bone. The scaffold recovered well when the force applied on it disappeared. Above all, the dual-channel scaffold had excellent bio-mechanical properties in implanting mandible, which provides a new idea for the reconstruction of irregular bone defects in the mandible and has good clinical development prospects.

18.
Med Image Anal ; 95: 103164, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38615431

RESUMO

Blessed by vast amounts of data, learning-based methods have achieved remarkable performance in countless tasks in computer vision and medical image analysis. Although these deep models can simulate highly nonlinear mapping functions, they are not robust with regard to the domain shift of input data. This is a significant concern that impedes the large-scale deployment of deep models in medical images since they have inherent variation in data distribution due to the lack of imaging standardization. Therefore, researchers have explored many domain generalization (DG) methods to alleviate this problem. In this work, we introduce a Hessian-based vector field that can effectively model the tubular shape of vessels, which is an invariant feature for data across various distributions. The vector field serves as a good embedding feature to take advantage of the self-attention mechanism in a vision transformer. We design paralleled transformer blocks that stress the local features with different scales. Furthermore, we present a novel data augmentation method that introduces perturbations in image style while the vessel structure remains unchanged. In experiments conducted on public datasets of different modalities, we show that our model achieves superior generalizability compared with the existing algorithms. Our code and trained model are publicly available at https://github.com/MedICL-VU/Vector-Field-Transformer.

19.
J Med Chem ; 67(8): 6624-6637, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38588467

RESUMO

The increased remodeling of the extracellular matrix (ECM) in pulmonary fibrosis (PF) generates bioactive ECM fragments called matricryptins, which include elastin-derived peptides (EDPs). The interaction between EDPs and their receptors, including elastin-binding protein (EBP), plays a crucial role in exacerbating fibrosis. Here, we present LXJ-02 for the first time, a novel ultralong-acting inhibitor that disrupts the EDPs/EBP peptide-protein interaction, promoting macrophages to secrete matrix metalloproteinase-12 (MMP-12), and showing great promise as a stable peptide. MMP-12 has traditionally been implicated in promoting inflammation and fibrosis in various acute and chronic diseases. However, we reveal a novel role of LXJ-02 that activates the macrophage-MMP-12 axis to increase MMP-12 expression and degrade ECM components like elastin. This leads to the preventing of PF while also improving EDP-EBP interaction. LXJ-02 effectively reverses PF in mouse models with minimal side effects, holding great promise as an excellent therapeutic agent for lung fibrosis.


Assuntos
Desenho de Fármacos , Elastina , Fibrose Pulmonar , Receptores de Superfície Celular , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/patologia , Fibrose Pulmonar/metabolismo , Animais , Camundongos , Elastina/química , Elastina/metabolismo , Humanos , Metaloproteinase 12 da Matriz/metabolismo , Peptídeos/farmacologia , Peptídeos/química , Peptídeos/síntese química , Camundongos Endogâmicos C57BL , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino
20.
Chem Sci ; 15(14): 5192-5200, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38577355

RESUMO

Layered transition metal oxides (NaxTMO2) possess attractive features such as large specific capacity, high ionic conductivity, and a scalable synthesis process, making them a promising cathode candidate for sodium-ion batteries (SIBs). However, NaxTMO2 suffer from multiple phase transitions and Na+/vacancy ordering upon Na+ insertion/extraction, which is detrimental to their electrochemical performance. Herein, we developed a novel cathode material that exhibits an abnormal P2-type structure at a stoichiometric content of Na up to 1. The cathode material delivers a reversible capacity of 108 mA h g-1 at 0.2C and 97 mA h g-1 at 2C, retaining a capacity retention of 76.15% after 200 cycles within 2.0-4.3 V. In situ diffraction studies demonstrated that this material exhibits an absolute solid-solution reaction with a low volume change of 0.8% during cycling. This near-zero-strain characteristic enables a highly stabilized crystal structure for Na+ storage, contributing to a significant improvement in battery performance. Overall, this work presents a simple yet effective approach to realizing high Na content in P2-type layered oxides, offering new opportunities for high-performance SIB cathode materials.

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