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1.
J Pharm Anal ; 14(3): 389-400, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38618248

RESUMO

Antibody-drug conjugates (ADCs) are a new type of targeting antibodies that conjugate with highly toxic anticancer drugs via chemical linkers to exert high specificity and efficient killing of tumor cells, thereby attracting considerable attention in precise oncology therapy. Cetuximab (Cet) is a typical antibody that offers the benefits of good targeting and safety for individuals with advanced and inoperable cutaneous squamous cell carcinoma (cSCC); however, its anti-tumor activity is limited to a single use. Cisplatin (CisPt) shows good curative effects; however, its adverse effects and non-tumor-targeting ability are major drawbacks. In this study, we designed and developed a new ADC based on a new cytotoxic platinum (IV) prodrug (C8Pt(IV)) and Cet. The so-called antibody-platinum (IV) prodrugs conjugates, named Cet-C8Pt(IV), showed excellent tumor targeting in cSCC. Specifically, it accurately delivered C8Pt(IV) into tumor cells to exert the combined anti-tumor effect of Cet and CisPt. Herein, metabolomic analysis showed that Cet-C8Pt(IV) promoted cellular apoptosis and increased DNA damage in cSCC cells by affecting the vitamin B6 metabolic pathway in tumor cells, thereby further enhancing the tumor-killing ability and providing a new strategy for clinical cancer treatment using antibody-platinum (IV) prodrugs conjugates.

2.
Ultrasound Med Biol ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632025

RESUMO

OBJECTIVE: We aimed to investigate the value of quantitative parameters derived from dynamic contrast-enhanced ultrasonography (DCE-US) and a combination of these quantitative parameters with the LR-M classification criteria in distinguishing hepatocellular carcinoma (HCC) nodules and non-HCC malignancies. METHODS: HCC and non-HCC malignant nodules were grouped using pathologic results, and each nodule was classified using CEUS LI-RADS 2017. Quantitative CEUS analysis of each nodule was performed using VueBox, and quantitative parameters were compared between the HCC and non-HCC groups. The diagnostic efficacy of the LR-5 category for HCC was analyzed using the LR-M classification criteria along with time-related quantitative parameters. RESULTS: Of the 190 malignant liver nodules, 137 and 53 were HCCs and non-HCC malignancies, respectively. The median values of quantitative parameters RT (rise time), TTP (time to peak), mTTl (mean transit time local), and FT (fall time) in the non-HCC malignant group were lower than those in the HCC group, with p < 0.05. There was a statistically significant difference in WiAUC (wash-in area under the curve), WoAUC (wash-out area under the curve), WiWoAUC (wash-in and wash-out area under the curve), and WoR (wash-out rate) values between HCC and non-HCC malignant groups, with p < 0.05. Using LR-M washout time <60 s and FT ≤21.2 s as the new diagnostic standard, the LR-5 category showed a sensitivity of 83.9%, specificity of 96.2%, and positive predictive value of 98.3% for HCC diagnosis. CONCLUSION: DCE-US can facilitate the distinction of HCCs and non-HCC malignancies. Non-HCC malignancies present with earlier peak enhancement and more rapid and marked washout than HCC nodules. The combination of the LR-M classification criteria and FT ≤21.2 s can significantly improve the diagnostic sensitivity of the LR-5 category for HCC.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38632049

RESUMO

OBJECTIVES: The study was designed to evaluate the superiority of the subxiphoid approach comparing with the lateral intercostal approach during the process of operation, and other perioperative indices. METHODS: Patients diagnosed anterior mediastinal disease in our hospital between January 2018 and October 2019 were prospectively assigned into two groups, receiving the lateral intercostal approach or the subxiphoid approach VATS to resect the disease. The PaCO2, SaO2, PaO2 and circulation changes were recorded during the operation, neutrophil-to-lymphocyte ratio, and other perioperative outcomes, including clinical and surgical results, operation time, blood loss, postoperative complication, postoperative pain score were compared. RESULTS: A total 59 patients diagnosed anterior mediastinal tumour or myasthenia gravis underwent the resection by VATS. 31 patients were treated with the subxiphoid approach, 28 patients were treated with the lateral intercostal approach. PaCO2 increased significantly and SaO2 remained stable in the subxiphoid group during the operation, while PaCO2 increased significantly and SaO2 decreased at the same time in the lateral intercostal group. Operations were more frequently interrupted for the hypoxia or circulation disturbance during the process of dissecting the thymus in the lateral intercostal approach. Compared with the lateral intercostal approach, patients in the subxiphoid approach experienced less inflammation reaction, and yielded lower pain score and shorter postoperative hospital stay. There were no significant differences in postoperative complications between the two groups. All these patients recovered well when discharged. CONCLUSIONS: Our study suggested that subxiphoid approach will influence pulmonary and circulation lesser than the lateral intercostal approach, and the whole procedure will be safer and easier, and the subxiphoid approach may be the ideal choice for the anterior mediastinal disease.

4.
Nanomaterials (Basel) ; 14(7)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38607177

RESUMO

Covalent organic frameworks (COFs) have been widely used in photocatalytic hydrogen peroxide (H2O2) production due to their favorable band structure and excellent light absorption. Due to the rapid recombination rate of charge carriers, however, their applications are mainly restricted. This study presents the design and development of two highly conjugated triazine-based COFs (TBP-COF and TTP-COF) and evaluates their photocatalytic H2O2 production performance. The nitrogen-rich structures and high degrees of conjugation of TBP-COF and TTP-COF facilitate improved light absorption, promote O2 adsorption, enhance their redox power, and enable the efficient separation and transfer of photogenerated charge carriers. There is thus an increase in the photocatalytic activity for the production of H2O2. When exposed to 10 W LED visible light irradiation at a wavelength of 420 nm, the pyridine-based TTP-COF produced 4244 µmol h-1 g-1 of H2O2 from pure water in the absence of a sacrificial agent. Compared to TBP-COF (1882 µmol h-1 g-1), which has a similar structure but lacks pyridine sites, TTP-COF demonstrated nearly 2.5 times greater efficiency. Furthermore, it exhibited superior performance compared to most previously published nonmetal COF-based photocatalysts.

5.
Sci Total Environ ; : 172466, 2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38626826

RESUMO

The burgeoning issue of plasmid-mediated resistance genes (ARGs) dissemination poses a significant threat to environmental integrity. However, the prediction of ARGs prevalence is overlooked, especially for emerging ARGs that are potentially evolving gene exchange hotspot. Here, we explored to classify plasmid or chromosome sequences and detect resistance gene prevalence by using DNABERT. Initially, the DNABERT fine-tuned in plasmid and chromosome sequences followed by multilayer perceptron (MLP) classifier could achieve 0.764 AUC (Area under curve) on external datasets across 23 genera, outperforming 0.02 AUC than traditional statistic-based model. Furthermore, Escherichia, Pseudomonas single genera based model were also be trained to explore its predict performance to ARGs prevalence detection. By integrating K-mer frequency attributes, our model could boost the performance to predict the prevalence of ARGs in an external dataset in Escherichia with 0.0281-0.0615 AUC and Pseudomonas with 0.0196-0.0928 AUC. Finally, we established a random forest model aimed at forecasting the relative conjugation transfer rate of plasmids with 0.7956 AUC, drawing on data from existing literature. It identifies the plasmid's repression status, cellular density, and temperature as the most important factors influencing transfer frequency. With these two models combined, they provide useful reference for quick and low-cost integrated evaluation of resistance gene transfer, accelerating the process of computer-assisted quantitative risk assessment of ARGs transfer in environmental field.

6.
World J Microbiol Biotechnol ; 40(5): 159, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607454

RESUMO

Gamma-aminobutyric acid (GABA) is a non-protein amino acid which is widely applied in agriculture and pharmaceutical additive industries. GABA is synthesized from glutamate through irreversible α-decarboxylation by glutamate decarboxylase. Recently, microbial synthesis has become an inevitable trend to produce GABA due to its sustainable characteristics. Therefore, reasonable microbial platform design and metabolic engineering strategies for improving production of GABA are arousing a considerable attraction. The strategies concentrate on microbial platform optimization, fermentation process optimization, rational metabolic engineering as key metabolic pathway modification, promoter optimization, site-directed mutagenesis, modular transporter engineering, and dynamic switch systems application. In this review, the microbial producers for GABA were summarized, including lactic acid bacteria, Corynebacterium glutamicum, and Escherichia coli, as well as the efficient strategies for optimizing them to improve the production of GABA.


Assuntos
Corynebacterium glutamicum , Ácido gama-Aminobutírico , Agricultura , Corynebacterium glutamicum/genética , Indústria Farmacêutica , Engenharia , Escherichia coli/genética
7.
Sensors (Basel) ; 24(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38610463

RESUMO

In recent years, soft robotic sensors have rapidly advanced to endow robots with the ability to interact with the external environment. Here, we propose a polymer optical fiber (POF) sensor with sensitive and stable detection performance for strain, bending, twisting, and pressing. Thus, we can map the real-time output light intensity of POF sensors to the spatial morphology of the elastomer. By leveraging the intrinsic correlations of neighboring sensors and machine learning algorithms, we realize the spatially resolved detection of the pressing and multi-dimensional deformation of elastomers. Specifically, the developed intelligent sensing system can effectively recognize the two-dimensional indentation position with a prediction accuracy as large as ~99.17%. The average prediction accuracy of combined strain and twist is ~98.4% using the random forest algorithm. In addition, we demonstrate an integrated intelligent glove for the recognition of hand gestures with a high recognition accuracy of 99.38%. Our work holds promise for applications in soft robots for interactive tasks in complex environments, providing robots with multidimensional proprioceptive perception. And it also can be applied in smart wearable sensing, human prosthetics, and human-machine interaction interfaces.

8.
Foods ; 13(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38611408

RESUMO

Jam is a popular traditional and modern food product for daily consumption. However, the benefits of mixed jams over single-fruit jams have not been thoroughly explored, with analyses limited to superficial indices. In this study, Xinjiang special Morus nigra L. and Prunus domestica L. were used as raw materials to prepare single-fruit and mixed jams, and their differences in antioxidants, organoleptic qualities, pH, texture, and color were analyzed. The dynamics of metabolites before and after thermal processing were assessed using untargeted metabolomics. The results indicate that the main metabolites were flavonoids, terpenoids, amino acids, phenolic acids, and carbohydrates. Flavonoid metabolites changed significantly after thermal processing, with 40 up-regulated and 13 down-regulated. During storage, polyphenols were the prominent differential metabolites, with fifty-four down-regulated and one up-regulated. Volatile aroma components were analyzed using gas chromatography-ion mobility spectrometry (GC-IMS); the aroma components E-2-hexenal, E-2-pentenal, 3-methylbutanal, 1-penten-3-ol, tetrahydro-linalool, 1-penten-3-one, hexyl propionate, isoamyl acetate, α-pinene, and propionic acid in mixed jam were significantly higher than in single-fruit jam. In this study, untargeted metabolomics and GC-IMS were used to provide a more comprehensive and in-depth evaluation system for jam analysis.

9.
Front Immunol ; 15: 1374900, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38605968

RESUMO

Introduction: Cells expressing taste signaling elements in non-gustatory tissues have been described as solitary chemosensory cells (SCCs) or tuft cells. These "taste-like" cells play a critical role in the maintenance of tissue homeostasis. Although the expression of SCC markers and taste signaling constituents has been identified in mouse gingivae, their role in periodontal homeostasis is still unclear. Methods: Public RNA sequencing datasets were re-analyzed and further validated with RT-PCR/qRT-PCR and immunofluorescent staining to explore the expression of TAS2Rs and downstream signaling constituents in mouse gingival fibroblasts (MGFs). The specific action of salicin on MGFs via Tas2r143 was validated with RNA silence, heterologous expression of taste receptor/Gα-gustducin and calcium imaging. The anti-inflammatory effects of salicin against LPS-induced MGFs were investigated in cell cultures, and were further validated with a ligature-induced periodontitis mouse model using Ga-gustducin-null (Gnat3-/-) mice. Results: The expression of Tas2r143, Gnat3, Plcb2, and TrpM5 was detected in MGFs. Moreover, salicin could activate Tas2r143, elicited taste signaling and thus inhibited LPS-induced chemokines expression (CXCL1, CXCL2, and CXCL5) in MGFs. Consistently, salicin-treatment inhibited periodontal bone loss, inflammatory/chemotactic factors expression, and neutrophil infiltration in periodontitis mice, while these effects were abolished in Gnat3-/- mice. Discussion: Gingival fibroblasts play a critical role in the maintenance of periodontal homeostasis via "SCC-like" activity. Salicin can activate Tas2r143-mediated bitter taste signaling and thus alleviate periodontitis in mouse, indicating a promising approach to the resolution of periodontal inflammation via stimulating the "SCC-like" function of gingival fibroblasts.


Assuntos
Álcoois Benzílicos , Glucosídeos , Lipopolissacarídeos , Periodontite , Transducina , Camundongos , Animais , Periodontite/tratamento farmacológico , Periodontite/metabolismo , Fibroblastos/metabolismo
10.
J Cardiothorac Surg ; 19(1): 209, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38616243

RESUMO

Uterine leiomyoma invading internal iliac vein and consequently disseminating into the right atrium is an extremely rare condition, and surgical strategy is controversial. Here, we reported a specific case with successful surgical resection through one-stage total hysterectomy, bilateral oophorectomy, and the intracardiovascular lesion. This procedure would be an optimal choice for uterine leiomyoma invading inferior vena cava and spreading to right atrium.


Assuntos
Leiomiomatose , Feminino , Humanos , Leiomiomatose/complicações , Leiomiomatose/diagnóstico por imagem , Leiomiomatose/cirurgia , Histerectomia , Átrios do Coração/cirurgia , Doenças Raras , Síncope
11.
Lung Cancer ; 191: 107558, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38569278

RESUMO

OBJECTIVES: Mediastinal neoplasms are typical but uncommon thoracic diseases with increasing incidence and unfavorable prognoses. A comprehensive understanding of their spatiotemporal distribution is essential for accurate diagnosis and timely treatment. However, previous studies are limited in scale and data coverage. Therefore, this study aims to elucidate the distribution of mediastinal lesions, offering valuable insights into this disease. MATERIALS AND METHODS: This multi-center, hospital-based observational study included 20 nationwide institutions. A retrospective search of electronic medical records from January 1st, 2009, to December 31st, 2020, was conducted, collecting sociodemographic data, computed tomography images, and pathologic diagnoses. Analysis focused on age, sex, time, location, and geographical region. Comparative assessments were made with global data from a multi-center database. RESULTS: Among 7,765 cases, thymomas (30.7%), benign mediastinal cysts (23.4%), and neurogenic tumors (10.0%) were predominant. Distribution varied across mediastinal compartments, with thymomas (39.6%), benign cysts (28.1%), and neurogenic tumors (51.9%) most prevalent in the prevascular, visceral, and paravertebral mediastinum, respectively. Age-specific variations were notable, with germ cell tumors prominent in patients under 18 and aged 18-29, while thymomas were more common in patients over 30. The composition of mediastinal lesions across different regions of China remained relatively consistent, but it differs from that of the global population. CONCLUSION: This study revealed significant heterogeneity in the spatiotemporal distribution of mediastinal neoplasms. These findings provide useful demographic data when considering the differential diagnosis of mediastinal lesions, and would be beneficial for tailoring disease prevention and control strategies.

12.
ACS Cent Sci ; 10(3): 684-694, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38559290

RESUMO

Fast and programmable transport of droplets on a substrate is desirable in microfluidic, thermal, biomedical, and energy devices. Photoresponsive surfactants are promising candidates to manipulate droplet motion due to their ability to modify interfacial tension and generate "photo-Marangoni" flow under light stimuli. Previous works have demonstrated photo-Marangoni droplet migration in liquid media; however, migration on other substrates, including solid and liquid-infused surfaces (LIS), remains an outstanding challenge. Moreover, models of photo-Marangoni migration are still needed to identify optimal photoswitches and assess the feasibility of new applications. In this work, we demonstrate 2D droplet motion on liquid surfaces and on LIS, as well as rectilinear motion in solid capillary tubes. We synthesize photoswitches based on spiropyran and merocyanine, capable of tension changes of up to 5.5 mN/m across time scales as short as 1.7 s. A millimeter-sized droplet migrates at up to 5.5 mm/s on a liquid, and 0.25 mm/s on LIS. We observe an optimal droplet size for fast migration, which we explain by developing a scaling model. The model also predicts that faster migration is enabled by surfactants that maximize the ratio between the tension change and the photoswitching time. To better understand migration on LIS, we visualize the droplet flow using tracer particles, and we develop corresponding numerical simulations, finding reasonable agreement. The methods and insights demonstrated in this study enable advances for manipulation of droplets for microfluidic, thermal and water harvesting devices.

13.
Microb Cell Fact ; 23(1): 98, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561780

RESUMO

BACKGROUND: Bacteria of the genus Photorhabdus and Xenorhabdus are motile, Gram-negative bacteria that live in symbiosis with entomopathogenic nematodes. Due to their complex life cycle, they produce a large number of specialized metabolites (natural products) encoded in biosynthetic gene clusters (BGC). Genetic tools for Photorhabdus and Xenorhabdus have been rare and applicable to only a few strains. In the past, several tools have been developed for the activation of BGCs and the deletion of individual genes. However, these often have limited efficiency or are time consuming. Among the limitations, it is essential to have versatile expression systems and genome editing tools that could facilitate the practical work. RESULTS: In the present study, we developed several expression vectors and a CRISPR-Cpf1 genome editing vector for genetic manipulations in Photorhabdus and Xenorhabdus using SEVA plasmids. The SEVA collection is based on modular vectors that allow exchangeability of different elements (e.g. origin of replication and antibiotic selection markers with the ability to insert desired sequences for different end applications). Initially, we tested different SEVA vectors containing the broad host range origins and three different resistance genes for kanamycin, gentamycin and chloramphenicol, respectively. We demonstrated that these vectors are replicative not only in well-known representatives, e.g. Photorhabdus laumondii TTO1, but also in other rarely described strains like Xenorhabdus sp. TS4. For our CRISPR/Cpf1-based system, we used the pSEVA231 backbone to delete not only small genes but also large parts of BGCs. Furthermore, we were able to activate and refactor BGCs to obtain high production titers of high value compounds such as safracin B, a semisynthetic precursor for the anti-cancer drug ET-743. CONCLUSIONS: The results of this study provide new inducible expression vectors and a CRISPR/CPf1 encoding vector all based on the SEVA (Standard European Vector Architecture) collection, which can improve genetic manipulation and genome editing processes in Photorhabdus and Xenorhabdus.


Assuntos
Produtos Biológicos , Photorhabdus , Xenorhabdus , Xenorhabdus/genética , Xenorhabdus/metabolismo , Photorhabdus/genética , Edição de Genes , Produtos Biológicos/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas
14.
Food Funct ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38606579

RESUMO

Gamma-aminobutyric acid (GABA) is the predominant amino acid in litchi pulp, known for its neuroregulatory effects and anti-inflammatory properties. Although previous research has highlighted the pro-inflammatory characteristics of litchi thaumatin-like protein (LcTLP), interplay between GABA and LcTLP in relation to inflammation remains unclear. This study aims to explore the hepatoprotective effects of the litchi pulp-derived GABA extract (LGE) against LcTLP-induced liver inflammation in mice and LO2 cells. In vivo experiments demonstrated that LGE significantly reduced the levels of aspartate transaminase and alanine transaminase, and protected the liver against infiltration of CD4+ and CD8+ T cells and histological injury induced by LcTLP. Pro-inflammatory cytokines including interleukin-6, interleukin-1ß, and tumor necrosis factor-α were also diminished by LGE. The LGE appeared to modulate the mitogen-activated protein kinase (MAPK) signaling pathway to exert its anti-inflammatory effects, as evidenced by a reduction of 47%, 35%, and 31% in phosphorylated p38, JNK, and ERK expressions, respectively, in the liver of the high-dose LGE group. Additionally, LGE effectively improved the translocation of gut microbiota by modulating its microbiological composition and abundance. In vitro studies have shown that LGE effectively counteracts the increase in reactive oxygen species, calcium ions, and pro-inflammatory cytokines induced by LcTLP. These findings may offer new perspectives on the health benefits and safety of litchi consumption.

15.
ACS Sens ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38593209

RESUMO

Surface-enhanced Raman scattering (SERS) technology, as an important analytical tool, has been widely applied in the field of chemical and biomedical sensing. Automated testing is often combined with biochemical analysis technologies to shorten the detection time and minimize human error. The present SERS substrates for sample detection are time-consuming and subject to high human error, which are not conducive to the combination of SERS and automated testing. Here, a novel honeycomb-inspired SERS microarray is designed for large-area automated testing of urease in saliva samples to shorten the detection time and minimize human error. The honeycomb-inspired SERS microarray is decorated with hexagonal microwells and a homogeneous distribution of silver nanostars. Compared with the other four common SERS substrates, the optimal honeycomb-inspired SERS microarray exhibits the best SERS performance. The RSD of 100 SERS spectra continuously collected from saliva samples is 6.56%, and the time of one detection is reduced from 5 min to 10 s. There is a noteworthy linear relationship with a R2 of 0.982 between SERS intensity and urease concentration, indicating the quantitative detection capability of the urease activity in saliva samples. The honeycomb-inspired SERS microarray, combined with automated testing, provides a new way in which SERS technology can be widely used in biomedical applications.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38591127

RESUMO

Sterol regulatory element binding protein (SREBP) cleavage-activating protein (SCAP) is a widely expressed membrane glycoprotein that acts as an important modulator of lipid metabolism and inflammatory stress. N-glycosylation of SCAP has been suggested to modulate cancer development, but its role in NASH is poorly understood. In this study, the N-glycosylation of SCAP was analyzed by using sequential trypsin proteolysis and glycosidase treatment. The liver cell lines expressing wild-type and N-glycosylation sites mutated SCAP were constructed to investigate the N-glycosylation role of SCAP in regulating inflammation and lipid accumulation as well as the underlying mechanisms. The hepatic SCAP protein levels were significantly increased in C57BL/6J mice fed with western diet and sweet water (WD+SW) and diabetic db/db mice, which exhibited typical liver steatosis and inflammation. In vitro, the enhanced N-glycosylation increased the protein stability of SCAP and hence increased its total protein levels, while the ablation of N-glycosylation significantly decreased SCAP protein stability and alleviated lipid accumulation and inflammation in hepatic cell lines. Mechanistically, the presence of SCAP N-glycosylation increased not only the SREBP1-mediated acetyl-CoA synthetase 2 (ACSS2) transcription but also the AMPK-mediated S659 phosphorylation of ACCS2 protein, causing the enhanced ACSS2 levels in nucleus and hence increasing the histone H3K27 acetylation (H3K27ac), which is a key epigenetic modification associated with NASH. Modulating ACSS2 expression or its location in cytoplasm abolished the effects of SCAP N-glycosylation on H3K27ac and lipid accumulation and inflammation. In conclusion, SCAP N-glycosylation aggravates inflammation and lipid accumulation through enhancing ACSS2-mediated H3K27ac in hepatocytes.

17.
Materials (Basel) ; 17(3)2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38591431

RESUMO

Owing to the high optical reflectivity of copper powder, the high-performance fabrication of copper alloys in the laser additive manufacturing (AM) field is problematic. To tackle this issue, this study employs the remelting process during laser powder bed fusion AM to fabricate defect-free and high-performance CuCrZr alloy. Compared to the non-remelting process, the remelting process yields finer grains, smaller precipitates, denser dislocations, and smaller dislocation cells. It realizes not only the dense molding of high laser reflectivity powders but also excellent mechanical properties and electrical conductivity (with an ultimate tensile strength of 329 MPa and conductivity of 96% IACS) without post-heat treatment. Furthermore, this study elucidates the influence of complex thermal gradients and multiple thermal cycles on the manufacturing process under the remelting process, as well as the internal mechanisms of microstructure evolution and performance improvement.

18.
Front Med (Lausanne) ; 11: 1284199, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38596793

RESUMO

Background: Atherosclerosis (AS) is a multifaceted disease characterized by disruptions in lipid metabolism, vascular inflammation, and the involvement of diverse cellular constituents. Recent investigations have progressively underscored the role of microRNA (miR) dysregulation in cardiovascular diseases, notably AS. Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) can effectively reduce circulating levels of low-density lipoprotein cholesterol (LDL-C) and lipoprotein (a) [Lp (a)], potentially fostering a more enduring phenotype for AS plaques. However, the underlying mechanisms by which PCSK9i enhances plaque stability remain unclear. In this study, we used microarray and bioinformatics techniques to analyze the regulatory impacts on gene expression pertinent to AS, thereby unveiling potential mechanisms underlying the plaque-stabilizing attributes of PCSK9i. Methods: ApoE-/- mice were randomly allocated into control, AS, PCSK9i, and Atorvastatin groups. The AS model was induced through a high-fat diet (HFD), succeeded by interventions: the PCSK9i group was subjected to subcutaneous SBC-115076 injections (8 mg/kg, twice weekly), and the Atorvastatin group received daily oral Atorvastatin (10 mg/kg) while on the HFD. Subsequent to the intervention phase, serum analysis, histological assessment using hematoxylin and eosin (H&E) and Oil Red O staining, microarray-centered miRNA analysis utilizing predictions from TargetScan and miRTarBase, and analyses using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were executed to illuminate potential pathways. Real-time fluorescence quantitative PCR (RT-qPCR) was employed to quantify the expression levels of target genes. Results: In comparison to the control group, the AS group displayed a significant elevation in blood lipid levels. Both PCSK9i and Atorvastatin effectively attenuated blood lipid levels, with PCSK9i exhibiting a more pronounced lipid-lowering impact, particularly concerning TG and LDL-C levels. Over the course of AS progression, the expression levels of mmu-miR-134, mmu-miR-141-5p, mmu-miR-17-3p, mmu-miR-195-3p, mmu-miR-210, mmu-miR-33-5p, mmu-miR-410, mmu-miR-411-5p, mmu-miR-499, mmu-miR-672-5p, mmu-miR-675-3p, and mmu-miR-301b underwent dynamic fluctuations. PCSK9i significantly down-regulated the expression of mmu-miR-186-5p, mmu-miR-222, mmu-miR-375-3p, and mmu-miR-494-3p. Further enrichment analysis disclosed that mmu-miR-186-5p, mmu-miR-222, mmu-miR-375-3p, and mmu-miR-494-3p were functionally enriched for cardiovascular smooth muscle cell proliferation, migration, and regulation. RT-qPCR results manifested that, in comparison to the AS group, PCSK9i significantly upregulated the expression of Wipf2, Pdk1, and Yap1 (p < 0.05). Conclusion: Aberrant miRNA expression may play a pivotal role in AS progression in murine models of AS. The subcutaneous administration of PCSK9i exerted anti-atherosclerotic effects by targeting the miR-186-5p/Wipf2 and miR-375-3p/Pdk1/Yap1 axes, thereby promoting the transition of AS plaques into a more stable form.

19.
Int J Biol Macromol ; 267(Pt 2): 131325, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38604425

RESUMO

Black rice anthocyanins (BRA) nanoparticles (NPs) were prepared using hyaluronic acid (HA), oxidized hyaluronic acid (OHA) and bovine serum albumin (BSA) to enhance the absorption and bioactivity of anthocyanins (ACNs). Results showed that HA/OHA-BSA-BRA NPs had a spherical morphology and excellent dispensability, with hydrated radius ~ 500 nm, zeta potential ~ - 30 mV, and encapsulation efficiency ~21 %. Moreover, using in vitro gastrointestinal release assay, we demonstrated that both BRA-loaded NPs exhibited effective controlled release properties of ACNs, significantly enhancing the accessibility of ACNs to the intestine. Cellular experiments showed that both two NPs had good biocompatibility and increased uptake of BRA. Furthermore, in comparison to the free BRA group, both BRA NPs groups significantly decreased the TEER value and increased the expression of tight junction proteins (Claudin 1, Occludin and ZO-1) in Caco-2 cell monolayers with LPS-induced damage. Therefore, our study demonstrated that HA/OHA-BSA-BRA NPs are promising carriers of ACNs and can effectively prevent the LPS-induced intestinal barrier injury in vitro.

20.
Front Immunol ; 15: 1369376, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638426

RESUMO

Introduction: Interleukin-2 (IL-2) is one of the first cytokines to be discovered as an immune agonist for cancer immunotherapy. Biased IL-2 variants had been discovered to eliminate Treg activation or enhance the tumor specific T cell cytotoxicity. However, all the biased IL-2 variants pose the risk to overstimulate immune response at a low-dose range. Here, we introduce a novel dual-MOA bispecific PD-1-IL-2v molecule with great anti-tumor efficacy in a high dosed manner. Methods: The novel IL-2 variant was designed by structural truncation and shuffling. The single armed bispecific PD-1-IL-2v molecule and IL-2v were studied by immune cell activations in vitro and in vivo and anti-tumor efficacy in mouse model. Results and discussion: The IL-2 variant in this bispecific antibody only binds to IL-2Rßγ complex in a fast-on/off manner without α, ß or γ single receptor binding. This IL-2v mildly activates T and NK cells without over stimulation, meanwhile it diminishes Treg activation compared to the wild type IL-2. This unique bispecific molecule with "ßγ-only" IL-2v can not only "in-cis" stimulate and expand CD8 T and NK cells moderately without Treg activation, but also block the PD-1/L1 interaction at a similar dose range with monoclonal antibody.


Assuntos
Interleucina-2 , Receptor de Morte Celular Programada 1 , Animais , Camundongos , Interleucina-2/genética , Interleucina-2/metabolismo , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Linhagem Celular Tumoral , Linfócitos T , Células Matadoras Naturais
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