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1.
Nature ; 633(8030): 575-581, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39232169

RESUMEN

Futuristic technologies such as morphing aircrafts and super-strong artificial muscles depend on metal alloys being as strong as ultrahigh-strength steel yet as flexible as a polymer1-3. However, achieving such 'strong yet flexible' alloys has proven challenging4-9 because of the inevitable trade-off between strength and flexibility5,8,10. Here we report a Ti-50.8 at.% Ni strain glass alloy showing a combination of ultrahigh yield strength of σy ≈ 1.8 GPa and polymer-like ultralow elastic modulus of E ≈ 10.5 GPa, together with super-large rubber-like elastic strain of approximately 8%. As a result, it possesses a high flexibility figure of merit of σy/E ≈ 0.17 compared with existing structural materials. In addition, it can maintain such properties over a wide temperature range of -80 °C to +80 °C and demonstrates excellent fatigue resistance at high strain. The alloy was fabricated by a simple three-step thermomechanical treatment that is scalable to industrial lines, which leads not only to ultrahigh strength because of deformation strengthening, but also to ultralow modulus by the formation of a unique 'dual-seed strain glass' microstructure, composed of a strain glass matrix embedded with a small number of aligned R and B19' martensite 'seeds'. In situ X-ray diffractometry shows that the polymer-like deformation behaviour of the alloy originates from a nucleation-free reversible transition between strain glass and R and B19' martensite during loading and unloading. This exotic alloy with the potential for mass producibility may open a new horizon for many futuristic technologies, such as morphing aerospace vehicles, superman-type artificial muscles and artificial organs.


Asunto(s)
Aleaciones , Módulo de Elasticidad , Vidrio , Polímeros , Titanio , Aleaciones/química , Titanio/química , Polímeros/química , Vidrio/química , Níquel/química , Temperatura , Ensayo de Materiales , Estrés Mecánico
2.
Front Pharmacol ; 15: 1445321, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39185313

RESUMEN

Background: Cancers arise from genetic and epigenetic abnormalities that affect oncogenes and tumor suppressor genes, compounded by gene mutations. The N6-methyladenosine (m6A) RNA modification, regulated by methylation regulators, has been implicated in tumor proliferation, differentiation, tumorigenesis, invasion, and metastasis. However, the role of m6A modification patterns in the tumor microenvironment of gastric cancer (GC) remains poorly understood. Materials and methods: In this study, we analyzed m6A modification patterns in 267 GC samples utilizing 31 m6A regulators. Using consensus clustering, we identified two unique subgroups of GC. Patients with GC were segregated into high- and low-infiltration cohorts to evaluate the infiltration proportions of the five prognostically significant immune cell types. Leveraging the differential genes in GC, we identified a "green" module via Weighted Gene Co-expression Network Analysis. A risk prediction model was established using the LASSO regression method. Results: The "green" module was connected to both the m6A RNA methylation cluster and immune infiltration patterns. Based on "Module Membership" and "Gene Significance", 37 hub genes were identified, and a risk prediction model incorporating nine hub genes was established. Furthermore, methylated RNA immunoprecipitation and RNA Immunoprecipitation assays revealed that YTHDF1 elevated the expression of DNMT3B, which synergistically promoted the initiation and development of GC. We elucidated the molecular mechanism underlying the regulation of DNMT3B by YTHDF1 and explored the crosstalk between m6A and 5mC modification. Conclusion: m6A RNA methylation regulators are instrumental in malignant progression and the dynamics of tumor microenvironment infiltration of GC. Assessing m6A modification patterns and tumor microenvironment infiltration characteristics in patients with GC holds promise as a valuable prognostic biomarker.

3.
Front Pharmacol ; 15: 1435269, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39193340

RESUMEN

Background: Colorectal cancer (CRC) is an aggressive primary intestinal malignancy with the third-highest incidence and second-highest mortality among all cancer types worldwide. Transcription factors (TFs) regulate cell development and differentiation owing to their ability to recognize specific DNA sequences upstream of genes. Numerous studies have demonstrated a strong correlation between TFs, the etiology of tumors, and therapeutic approaches. Here, we aimed to explore prognosis-related TFs and comprehend their carcinogenic mechanisms, thereby offering novel insights into the diagnosis and management of CRC. Materials and Methods: Differentially expressed TFs between CRC and normal tissues were identified leveraging The Cancer Genome Atlas database, Weighted correlation network analysis and Cox regression analysis were performed to identify prognosis-related TFs. The cellular functions of hub TF zinc finger E-box binding homeobox 1 (ZEB1) were determined using by 5-ethynyl-2'-deoxyuridine and cell invasion assays in CRC cells. RNA-sequencing, Kyoto Encyclopedia of Genes and Genomes enrichment, and gene set enrichment analyses were used to identify the cellular processes in which ZEB1 participates. Immunoaffinity purification, silver staining mass spectrometry, and a chromatin immunoprecipitation assay were conducted to search for proteins that might interact with ZEB1 and the target genes they jointly regulate. Results: Thirteen central TFs related to prognosis were identified through bioinformatics analysis techniques. Among these TFs, ZEB1 emerged as the TF most closely associated with CRC, as determined through a combination of regulatory network diagrams, survival curves, and phenotype analyses. ZEB1 promotes CRC cell growth by recruiting the NuRD(MTA1) complex, and the ZEB1/NuRD(MTA1) complex transcriptionally represses glycolysis-associated tumor suppressor genes. Conclusion: Our study not only identified a hub biomarker related to CRC prognosis but also revealed the specific molecular mechanisms through which ZEB1 affects cancer progression. These insights provide crucial evidence for the diagnosis of CRC and potential treatment opportunities.

4.
Cell Death Dis ; 15(8): 597, 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39154024

RESUMEN

The metastasis-associated protein (MTA) family plays a crucial role in the development of breast cancer, a common malignancy with a high incidence rate among women. However, the mechanism by which each member of the MTA family contributes to breast cancer progression is poorly understood. In this study, we aimed to investigate the roles of MTA1, MTA3, and tripartite motif-containing 21 (TRIM21) in the proliferation, invasion, epithelial-mesenchymal transition (EMT), and stem cell-like properties of breast cancer cells in vivo and in vitro. The molecular mechanisms of the feedback loop between MTA1 and MTA3/TRIM21 regulated by estrogen were explored using Chromatin immunoprecipitation (ChIP), luciferase reporter, immunoprecipitation (IP), and ubiquitination assays. These findings demonstrated that MTA1 acts as a driver to promote the progression of breast cancer by repressing the transcription of tumor suppressor genes, including TRIM21 and MTA3. Conversely, MTA3 inhibited MTA1 transcription and TRIM21 regulated MTA1 protein stability in breast cancer. Estrogen disrupted the balance between MTA1 and MTA3, as well as between MTA1 and TRIM21, thereby affecting stemness and the EMT processes in breast cancer. These findings suggest that MTA1 plays a vital role in stem cell fate and the hierarchical regulatory network of EMT through negative feedback loops with MTA3 or TRIM21 in response to estrogen, supporting MTA1, MTA3, and TRIM21 as potential prognostic biomarkers and MTA1 as a treatment target for future breast cancer therapies.


Asunto(s)
Neoplasias de la Mama , Transición Epitelial-Mesenquimal , Estrógenos , Histona Desacetilasas , Células Madre Neoplásicas , Proteínas Represoras , Transactivadores , Humanos , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Femenino , Proteínas Represoras/metabolismo , Proteínas Represoras/genética , Transactivadores/metabolismo , Transactivadores/genética , Estrógenos/farmacología , Estrógenos/metabolismo , Histona Desacetilasas/metabolismo , Histona Desacetilasas/genética , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/patología , Transición Epitelial-Mesenquimal/efectos de los fármacos , Transición Epitelial-Mesenquimal/genética , Animales , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Ratones , Proliferación Celular/efectos de los fármacos , Línea Celular Tumoral , Retroalimentación Fisiológica/efectos de los fármacos , Ribonucleoproteínas/metabolismo , Ribonucleoproteínas/genética , Ratones Desnudos , Células MCF-7 , Ratones Endogámicos BALB C , Proteínas de Neoplasias
5.
Cancer Lett ; 600: 217157, 2024 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-39127340

RESUMEN

Deregulation of E3 ubiquitin ligases drives the proliferation and metastasis of various cancers; however, the underlying mechanisms remain unknown. This study aimed to investigate the role of tripartite motif-containing 22 (TRIM22), a poorly investigated E3 ubiquitin ligase in the TRIM family, as a tumor suppressor in breast cancer. High expression of TRIM22 in breast cancer correlated with better prognosis. Functional experiments demonstrated that TRIM22 significantly inhibited the proliferation and invasion of breast cancer cells. Label-free proteomics and biochemical analyses revealed that the copper chaperone for superoxide dismutase (CCS), an oncoprotein that is upregulated in breast cancer and promotes the growth and invasion of breast cancer cells, was a target of TRIM22 for degradation via K27-linked ubiquitination. Notably, the ability of the coiled-coil domain-defective mutants of TRIM22 to induce CCS ubiquitination and degradation diminished, with lysine 76 of the CCS serving as the ubiquitination site. Moreover, the TRIM22-mediated inhibition of the proliferation and invasion of breast cancer cells was restored by ectopic CCS expression. RNA-sequencing experiments using Gene Set Enrichment Analysis demonstrated that TRIM22 is involved in the JAK-STAT signaling pathway. TRIM22 overexpression also improved reactive oxygen species levels in breast cancer cells and inhibited STAT3 phosphorylation, which was restored via CCS overexpression or N-acetyl-l-cysteine treatment. Chromatin immunoprecipitation-quantitative polymerase chain reaction results showed that TRIM22 overexpression decreased the enrichment of phosphorylated STAT3 in FN1, VIM and JARID2 promoters. Clinically, low TRIM22 expression correlated with high CCS expression and decreased survival rates in patients with breast cancer. Moreover, TRIM22 upregulation was associated with a better prognosis in patients with breast cancer who received classical therapy. TRIM22 expression was downregulated in many cancer types, including colon, kidney, lung, and prostate cancers. To the best of our knowledge, the E3 ubiquitin ligase TRIM22 was first reported as a tumor suppressor that inhibits the proliferation and invasion of breast cancer cells through CCS ubiquitination and degradation. TRIM22 is a potential prognostic biomarker in patients with breast cancer.


Asunto(s)
Neoplasias de la Mama , Proliferación Celular , Antígenos de Histocompatibilidad Menor , Factor de Transcripción STAT3 , Transducción de Señal , Proteínas de Motivos Tripartitos , Ubiquitinación , Femenino , Humanos , Neoplasias de la Mama/patología , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Células MCF-7 , Antígenos de Histocompatibilidad Menor/genética , Antígenos de Histocompatibilidad Menor/metabolismo , Invasividad Neoplásica , Pronóstico , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteolisis , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Factor de Transcripción STAT3/metabolismo , Factor de Transcripción STAT3/genética , Proteínas de Motivos Tripartitos/genética , Proteínas de Motivos Tripartitos/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética
6.
Artículo en Inglés | MEDLINE | ID: mdl-39083392

RESUMEN

Current whole slide image (WSI) segmentation aims at extracting tumor regions from the background. Unlike this, segmenting distinct tumor areas (instances) within a WSI driven by limited annotated data remains under-explored. In this paper, we formally propose semisupervised instance segmentation (Semi-IS) in WSIs. We address a key challenge: learning intra-class similarity and inter-class dissimilarity driven by unlabeled data. Specifically, we generally perceive the patch as composed of tokens (together), not the patch alone. We employ contrastive learning to develop a segmentation framework. In the SemiIS, we find that the boundaries of segmented instances are usually disturbed by noise. We jointly eliminate and preserve noise features to address this problem. We conduct extensive experiments to evaluate the effectiveness and generalizability of Semi-IS, including histopathology and cellular pathology. The results show that in clinical multi instance segmentation tasks, Semi-IS achieves almost fullsupervised state-of-the-art results with only 30% annotated data. Semi-IS can improve segmentation accuracy by about 2% on public cell pathology datasets.

7.
Exp Gerontol ; 194: 112489, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38936439

RESUMEN

BACKGROUND: Age-related hearing loss (ARHL) - also termed presbycusis - is prevalent among older adults, leading to a range of issues. Although considerable progress in the understanding of ARHL over the decades, available reports lack data from recent years and do not comprehensively reflect the latest advancements and trends. Therefore, our study sought to assess research hotspots and trends in ARHL over the past 5 years to provide the basis for future research. MATERIALS AND METHODS: The Web of Science Core Collection database was searched and screened from January 1, 2019 to October 21, 2023, according to the inclusion criteria. CiteSpace (5.8.R3), VOSviewer (1.6.19), and Microsoft Excel 2019 were employed for bibliometric analysis and visualization. RESULTS: 3084 articles from 92 countries led by the United States and China were included. There has been a steady upward trend in the number of publications from 2019 to 2023. The most productive institutions, authors, and journals are Johns Hopkins University (n = 113), Lin FR (n = 66), and Ear and Hearing (n = 135), respectively. Trend topic analyses revealed that "cochlear synaptopathy" and "dementia" were the predominant foci. Keywords, including "individuals" and "national health", began to appear. CONCLUSION: Over the past 5 years, the annual number of publications has increased significantly and will continue to do so. Research on the mechanism of ARHL, represented by "oxidative stress", is a continuing focus. Emerging topics such as "individual differences" and "national health" may be potential future hotspots in this field.


Asunto(s)
Bibliometría , Presbiacusia , Humanos , Presbiacusia/epidemiología , Investigación Biomédica/tendencias , Anciano
8.
J Pharm Biomed Anal ; 248: 116266, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38879950

RESUMEN

Gastrodiae Rhizoma was proven to have anti-inflammatory activity based on its main component of 4-hydroxybenzyl alcohol (4-HBA) and gastrodin (GAS). However, the anti-inflammatory activity of other phenols has been less reported. In this study, the n-BuOH extract was selected as the active anti-inflammatory part of Gastrodiae Rhizoma based on the LPS-induced inflammatory BV-2 cells. The spectral-effect relationship analysis of the n-BuOH extract showed the main effective components were GAS, 4-HBA, parishin A (PA), parishin B (PB), and parishin C (PC). Among them, PB could reduce LPS-induced expression of nitric oxide (NO), intracellular ROS, TNF-α, IL-6, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2). Molecular docking predicted that PB had a good binding capacity to AMPKα and SIRT1 proteins of -12.1 kJ/mol and -7.6 kJ/mol, respectively. The Western Blot results further demonstrated that PB could inhibit NF-κB pathway by activating AMPK/SIRT1 pathway, thus exerting anti-LPS-induced neuroinflammatory effects. This study provides a referable idea for solving the problem of unclear action of TCM with complex compositions and is of great significance for the development of innovative medicines of traditional Chinese medicine.


Asunto(s)
Antiinflamatorios , Gastrodia , Simulación del Acoplamiento Molecular , Óxido Nítrico Sintasa de Tipo II , Óxido Nítrico , Rizoma , Gastrodia/química , Ratones , Animales , Antiinflamatorios/farmacología , Antiinflamatorios/química , Rizoma/química , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Alcoholes Bencílicos/farmacología , Alcoholes Bencílicos/química , Línea Celular , Lipopolisacáridos/farmacología , Ciclooxigenasa 2/metabolismo , FN-kappa B/metabolismo , Glucósidos/farmacología , Glucósidos/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Especies Reactivas de Oxígeno/metabolismo
9.
Adv Mater ; 36(35): e2404192, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38925664

RESUMEN

Rapid development of smart technologies poses a big challenge for magnetostrictive materials, which should not only permit isotropic and hysteresis-free actuation (i.e., nonhysteretic volume change) in magnetic fields, but also have high strength and high ductility. Unfortunately, the magnetostriction from self-assembly of ferromagnetic domains is volume-conserving; the volume magnetostriction from field-induced first-order phase transition has large intrinsic hysteresis; and most prototype magnetostrictive materials are intrinsically brittle. Here, a magnetic high-entropy alloy (HEA) Fe35Co35Al10Cr10Ni10 is reported that can rectify these challenges, exhibiting an unprecedented combination of large nonhysteretic volume magnetostriction, high tensile strength and large elongation strain, over a wide working temperature range from room temperature down to 100 K. Its exceptional properties stem from a dual-phase microstructure, where the face-centered cubic (FCC) matrix phase with nanoscale compositional and structural fluctuations can enable a magnetic-field-induced transition from low-spin small-volume state to high-spin large-volume state, and the ordered body-centered cubic (BCC) B2 phase contributes to mechanical strengthening. The present findings may provide insights into designing unconventional and technologically important magnetostrictive materials.

10.
Front Med ; 18(4): 571-596, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38806988

RESUMEN

Epigenetic modifications including DNA methylation, histone modifications, chromatin remodeling, and RNA modifications complicate gene regulation and heredity and profoundly impact various physiological and pathological processes. In recent years, accumulating evidence indicates that epigenetics is vulnerable to environmental changes and regulates the growth, development, and diseases of individuals by affecting chromatin activity and regulating gene expression. Environmental exposure or induced epigenetic changes can regulate the state of development and lead to developmental disorders, aging, cardiovascular disease, Alzheimer's disease, cancers, and so on. However, epigenetic modifications are reversible. The use of specific epigenetic inhibitors targeting epigenetic changes in response to environmental exposure is useful in disease therapy. Here, we provide an overview of the role of epigenetics in various diseases. Furthermore, we summarize the mechanism of epigenetic alterations induced by different environmental exposures, the influence of different environmental exposures, and the crosstalk between environmental variation epigenetics, and genes that are implicated in the body's health. However, the interaction of multiple factors and epigenetics in regulating the initiation and progression of various diseases complicates clinical treatments. We discuss some commonly used epigenetic drugs targeting epigenetic modifications and methods to prevent or relieve various diseases regulated by environmental exposure and epigenetics through diet.


Asunto(s)
Metilación de ADN , Exposición a Riesgos Ambientales , Salud Ambiental , Epigénesis Genética , Humanos , Exposición a Riesgos Ambientales/efectos adversos
11.
Vet Res ; 55(1): 60, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750480

RESUMEN

Bacterial ClpB is an ATP-dependent disaggregate that belongs to the Hsp100/Clp family and facilitates bacterial survival under hostile environmental conditions. Streptococcus agalactiae, which is regarded as the major bacterial pathogen of farmed Nile tilapia (Oreochromis niloticus), is known to cause high mortality and large economic losses. Here, we report a ClpB homologue of S. agalactiae and explore its functionality. S. agalactiae with a clpB deletion mutant (∆clpB) exhibited defective tolerance against heat and acidic stress, without affecting growth or morphology under optimal conditions. Moreover, the ΔclpB mutant exhibited reduced intracellular survival in RAW264.7 cells, diminished adherence to the brain cells of tilapia, increased sensitivity to leukocytes from the head kidney of tilapia and whole blood killing, and reduced mortality and bacterial loads in a tilapia infection assay. Furthermore, the reduced virulence of the ∆clpB mutant was investigated by transcriptome analysis, which revealed that deletion of clpB altered the expression levels of multiple genes that contribute to the stress response as well as certain metabolic pathways. Collectively, our findings demonstrated that ClpB, a molecular chaperone, plays critical roles in heat and acid stress resistance and virulence in S. agalactiae. This finding provides an enhanced understanding of the functionality of this ClpB homologue in gram-positive bacteria and the survival strategy of S. agalactiae against immune clearance during infection.


Asunto(s)
Enfermedades de los Peces , Chaperonas Moleculares , Infecciones Estreptocócicas , Streptococcus agalactiae , Estrés Fisiológico , Animales , Ratones , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Cíclidos , Enfermedades de los Peces/microbiología , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Células RAW 264.7 , Infecciones Estreptocócicas/veterinaria , Infecciones Estreptocócicas/microbiología , Streptococcus agalactiae/fisiología , Streptococcus agalactiae/patogenicidad , Streptococcus agalactiae/genética , Virulencia
12.
Discov Oncol ; 15(1): 195, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38809316

RESUMEN

INTRODUCTION: Lung cancer (LC) is the most common solid tumor and is currently considered the primary cause of cancer-related deaths worldwide. In clinical efficacy studies, it was not difficult to find that the combination of SFI and chemotherapy could improve the general condition of patients, reduce the side effects of chemotherapy drugs, and have a cooperative antitumor effect in NSCLC patients. However, whether SFI can be used as a novel antitumor drug is still unknown. METHODS: First, meta-analysis aimed to explore the efficacy of SFI in NSCLC patients, and SFI was identified by ultra-performance liquid chromatography‒mass spectrometry (UPLC‒MS). Cell proliferation, migration, and invasion were explored by Cell Counting Kit-8 (CCK-8), scratch healing, and Transwell assays, respectively. Cell cycle and apoptosis assays were performed by flow cytometry. Transcriptome sequencing analysis was performed in four NSCLC cell lines. Differential expression analysis was used to identify potential targets. Apoptosis-related protein levels were detected by Western blotting assays. The effects of SFI in NSCLC were further investigated by mouse xenografts. RESULTS: SFI could markedly improve the chemotherapy efficacy of NSCLC patients. The main active ingredients include flavonoids and terpenoids, which can effectively exert antitumor effects. SFI could not only inhibit tumor cell proliferation and cell migration/invasion but also regulate the cell cycle and promote tumor cell apoptosis. In NSCLC, SFI could enhance the transcription level of the CHOP gene, thereby upregulating the expression of the proapoptotic proteins Bax and caspase 3, and inhibiting the expression of the antiapoptotic protein Bcl-2. SFI hindered the growth of mouse NSCLC xenografts in vivo. CONCLUSIONS: SFI hindered tumor progression and might promote apoptosis by increasing the expression of Bax, caspase 3 and decreasing the level of Bcl-2 in NSCLC.

13.
Materials (Basel) ; 17(9)2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38730751

RESUMEN

Geopolymer concrete (GPC) represents an innovative green and low-carbon construction material, offering a viable alternative to ordinary Portland cement concrete (OPC) in building applications. However, existing studies tend to overlook the recyclability aspect of GPC for future use. Various structural applications necessitate the use of concrete with distinct strength characteristics. The recyclability of the parent concrete is influenced by these varying strengths. This study examined the recycling potential of GPC across a spectrum of strength grades (40, 60, 80, and 100 MPa, marked as C40, C60, C80, and C100) when subjected to freeze-thaw conditions. Recycling 5-16 mm recycled geopolymer coarse aggregate (RGAs) from GPC prepared from 5 to 16 mm natural coarse aggregates (NAs). The cementitious material comprised 60% metakaolin and 40% slag, with natural gravel serving as the NAs, and the alkali activator consisting of sodium hydroxide solution and sodium silicate solution. The strength of the GPC was modulated by altering the Na/Al ratio. After 350 freeze-thaw cycles, the GPC specimens underwent crushing, washing, and sieving to produce RGAs. Subsequently, their physical properties (apparent density, water absorption, crushing index, and attached mortar content and microstructure (microhardness, SEM, and XRD) were thoroughly examined. The findings indicated that GPC with strength grades of C100, C80, and C60 were capable of enduring 350 freeze-thaw cycles, in contrast to C40, which did not withstand these conditions. RGAs derived from GPC of strength grades C100 and C80 complied with the criteria for Class II recycled aggregates, whereas RGAs produced from GPC of strength grade C60 aligned with the Class III level. A higher-strength grade in the parent concrete correlated with enhanced performance characteristics in the resulting recycled aggregates.

14.
Int J Paediatr Dent ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38725105

RESUMEN

BACKGROUND: Changes in healthy and inflamed pulp on periapical radiographs are traditionally so subtle that they may be imperceptible to human experts, limiting its potential use as an adjunct clinical diagnostic feature. AIM: This study aimed to investigate the feasibility of an image-analysis technique based on the convolutional neural network (CNN) to detect irreversible pulpitis in primary molars on periapical radiographs (PRs). DESIGN: This retrospective study was performed in two health centres. Patients who received indirect pulp therapy at Peking University Hospital for Stomatology were retrospectively identified and randomly divided into training and validation sets (8:2). Using PRs as input to an EfficientNet CNN, the model was trained to categorise cases into either the success or failure group and externally tested on patients who presented to our affiliate institution. Model performance was evaluated using sensitivity, specificity, accuracy and F1 score. RESULTS: A total of 348 PRs with deep caries were enrolled from the two centres. The deep learning model achieved the highest accuracy of 0.90 (95% confidence interval: 0.79-0.96) in the internal validation set, with an overall accuracy of 0.85 in the external test set. The mean greyscale value was higher in the failure group than in the success group (p = .013). CONCLUSION: The deep learning-based model could detect irreversible pulpitis in primary molars with deep caries on PRs. Moreover, this study provides a convenient and complementary method for assessing pulp status.

15.
Materials (Basel) ; 17(8)2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38673073

RESUMEN

The global construction industry is increasingly utilizing concrete prepared from recycled aggregate as a substitute for natural aggregate. However, the subpar performance of recycled fine aggregate (RFA) has resulted in its underutilization, particularly in the structural concrete exposed to challenging environments, including those involving chlorine salts and freeze-thaw climates. This study aimed to enhance the performance of RFA as a substitute for river sand in concrete as well as fulfill the present demand for fine aggregates in the construction sector by utilizing accelerated carbonation treatment to create fully recycled aggregate concrete (FRAC) composed of 100% recycled coarse and fine aggregates. The impacts of incorporating carbonated recycled fine aggregate (C-RFA) at various replacement rates (0%, 25%, 50%, 75%, and 100%) on the mechanical and durability properties of FRAC were investigated. The results showed that the physical properties of C-RFA, including apparent density, water absorption, and crushing value, were enhanced compared to that of RFA. The compressive strength of C-RFC100 was 19.8% higher than that of C-RFC0, while the water absorption decreased by 14.6%. In a comparison of C-RFC0 and C-RFC100, the chloride permeability coefficients showed a 50% decrease, and the frost resistance increased by 27.6%. According to the findings, the mechanical and durability properties, the interfacial transition zones (ITZs), and micro-cracks of the C-RFC were considerably enhanced with an increased C-RFA content.

16.
Cancer Immunol Immunother ; 73(6): 99, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38619623

RESUMEN

PURPOSE: Neoadjuvant PD-1 blockade combined with chemotherapy is a promising treatment for resectable non-small cell lung cancer (NSCLC), yet the immunological mechanisms contributing to tumor regression and biomarkers corresponding to different pathological responses remain unclear. METHODS: Using dynamic and paired blood samples from NSCLC patients receiving neoadjuvant chemoimmunotherapy, we analyzed the frequencies of CD8 + T-cell and Treg subsets and their dynamic changes during neoadjuvant treatment through flow cytometry. Cytokine profiles and function-related gene expression of CD8 + T cells and Tregs were analyzed through flow cytometry and mRNA-seq. Infiltrating T-cell subsets in resected tissues from patients with different pathological responses were analyzed through multiplex immunofluorescence. RESULTS: Forty-two NSCLC patients receiving neoadjuvant chemoimmunotherapy were enrolled and then underwent surgical resection and pathological evaluation. Nineteen patients had pCR (45%), 7 patients had MPR (17%), and 16 patients had non-MPR (38%). In patients with pCR, the frequencies of CD137 + CD8 + T cells (P = 0.0475), PD-1 + Ki-67 + CD8 + T cells (P = 0.0261) and Tregs (P = 0.0317) were significantly different from those of non-pCR patients before treatment. pCR patients usually had low frequencies of CD137 + CD8 + T cells, PD-1 + Ki-67 + CD8 + T cells and Tregs, and their AUCs were higher than that of tissue PD-L1 expression. Neoadjuvant chemoimmunotherapy markedly improved CD8 + T-cell proliferation and activation, especially in pCR patients, as the frequencies of CD137 + CD8 + (P = 0.0136) and Ki-67 + CD8 + (P = 0.0391) T cells were significantly increased. The blood levels of cytokines such as IL-2 (P = 0.0391) and CXCL10 (P = 0.0195) were also significantly increased in the pCR group, which is consistent with the high density of activated cytotoxic T cells at the tumor site (P < 0.0001). CONCLUSION: Neoadjuvant chemoimmunotherapy drives CD8 + T cells toward a proliferative and active profile. The frequencies of CD137 + CD8 + T cells, PD-1 + Ki-67 + CD8 + T cells and Tregs at baseline might predict the response to neoadjuvant chemoimmunotherapy in NSCLC patients. The increase in IL-2 and CXCL10 might reflect the chemotaxis and enrichment of cytotoxic T cells at the tumor site and a better response to neoadjuvant chemoimmunotherapy.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Terapia Neoadyuvante , Citocinas , Interleucina-2 , Antígeno Ki-67 , Receptor de Muerte Celular Programada 1 , Neoplasias Pulmonares/tratamiento farmacológico , Subgrupos de Linfocitos T
17.
Int J Mol Sci ; 25(5)2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38474068

RESUMEN

Primary failure of eruption (PFE) is a rare oral disease with an incidence rate of 0.06%. It is characterized by abnormal eruption mechanisms that disrupt tooth eruption. The underlying pathogenic genetic variant and mechanism of PFE remain largely unknown. The purpose of this study was to explore the role of a novel transmembrane protein 119 (TMEM119) mutation in two PFE patients in a Chinese family. Information collection was performed on the family with a diagnosis of PFE, and blood samples from patients and healthy family members were extracted. Whole-exome sequencing was performed. Bioinformatics analysis revealed that a heterozygous variant in the TMEM119 gene (c.G143A, p.S48L) was a disease-associated mutation in this family. Recombinant pcDNA3.1 plasmid-containing wild-type and mutant TMEM119 expression cassettes were successfully constructed and transfected into MC3T3-E1 cells, respectively. The results of in vitro analysis suggested that the subcellular distribution of the TMEM119 protein was transferred from the cell cytoplasm to the nucleus, and the ability of cells to proliferate and migrate as well as glycolytic and mineralized capacities were reduced after mutation. Furthermore, rescue assays showed that activating transcription factor 4 (ATF4) overexpression rescued the attenuated glycolysis and mineralization ability of cells. Results of in vivo analysis demonstrated that TMEM119 was mainly expressed in the alveolar bone around the mouse molar germs, and the expression level increased with tooth eruption, demonstrated using immunohistochemistry and immunofluorescence. Collectively, the novel TMEM119 mutation is potentially pathogenic in the PFE family by affecting the glucose metabolism and mineralized function of osteoblasts, including interaction with ATF4. Our findings broaden the gene mutation spectrum of PFE and further elucidate the pathogenic mechanism of PFE.


Asunto(s)
Osteogénesis , Erupción Dental , Humanos , Animales , Ratones , Erupción Dental/genética , Receptor de Hormona Paratiroídea Tipo 1/genética , Mutación , Glucólisis
18.
Angew Chem Int Ed Engl ; 63(21): e202400926, 2024 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-38529812

RESUMEN

Hydrogen-bonded organic frameworks (HOFs) are porous nanomaterials that offer exceptional biocompatibility and versatility for integrating proteins for biomedical applications. This minireview concisely discusses recent advancements in the chemistry and functionality of protein-HOF interfaces. It particularly focuses on strategic methodologies, such as the careful selection of building blocks and the genetic engineering of proteins, to facilitate protein-HOF interactions. We examine the role of enzyme encapsulation within HOFs, highlighting its capability to preserve enzyme function, a crucial aspect for applications in biosensing and disease diagnosis. Moreover, we discuss the emerging utility of nanoscale HOFs for intracellular protein delivery, illustrating their applicability as nanoreactors for intracellular catalysis and neuroprotective biorthogonal catalysis within cellular compartments. We highlight the significant advancement of designing biodegradable HOFs tailored for cytosolic protein delivery, underscoring their promising application in targeted cancer therapies. Finally, we provide a perspective viewpoint on the design of biocompatible protein-HOF assemblies, underlining their promising prospects in drug delivery, disease diagnosis, and broader biomedical applications.


Asunto(s)
Enlace de Hidrógeno , Proteínas , Humanos , Proteínas/química , Proteínas/metabolismo , Materiales Biocompatibles/química , Estructuras Metalorgánicas/química , Sistemas de Liberación de Medicamentos
19.
Med Phys ; 51(4): 2772-2787, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37921396

RESUMEN

BACKGROUND: A compact PET/SPECT/CT system Inliview-3000B has been developed to provide multi-modality information on small animals for biomedical research. Its PET subsystem employed a dual-layer-offset detector design for depth-of-interaction capability and higher detection efficiency, but the irregular design caused some difficulties in calculating the normalization factors and the sensitivity map. Besides, the relatively larger (2 mm) crystal cross-section size also posed a challenge to high-resolution image reconstruction. PURPOSE: We present an efficient image reconstruction method to achieve high imaging performance for the PET subsystem of Inliview-3000B. METHODS: List mode reconstruction with efficient system modeling was used for the PET imaging. We adopt an on-the-fly multi-ray tracing method with random crystal sampling to model the solid angle, crystal penetration and object attenuation effect, and modify the system response model during each iteration to improve the reconstruction performance and computational efficiency. We estimate crystal efficiency with a novel iterative approach that combines measured cylinder phantom data with simulated line-of-response (LOR)-based factors for normalization correction before reconstruction. Since it is necessary to calculate normalization factors and the sensitivity map, we stack the two crystal layers together and extend the conventional data organization method here to index all useful LORs. Simulations and experiments were performed to demonstrate the feasibility and advantage of the proposed method. RESULTS: Simulation results showed that the iterative algorithm for crystal efficiency estimation could achieve good accuracy. NEMA image quality phantom studies have demonstrated the superiority of random sampling, which is able to achieve good imaging performance with much less computation than traditional uniform sampling. In the spatial resolution evaluation based on the mini-Derenzo phantom, 1.1 mm hot rods could be identified with the proposed reconstruction method. Reconstruction of double mice and a rat showed good spatial resolution and a high signal-to-noise ratio, and organs with higher uptake could be recognized well. CONCLUSION: The results validated the superiority of introducing randomness into reconstruction, and demonstrated its reliability for high-performance imaging. The Inliview-3000B PET subsystem with the proposed image reconstruction can provide rich and detailed information on small animals for preclinical research.


Asunto(s)
Tomografía de Emisión de Positrones , Tomografía Computarizada de Emisión de Fotón Único , Ratas , Ratones , Animales , Reproducibilidad de los Resultados , Tomografía de Emisión de Positrones/métodos , Simulación por Computador , Fantasmas de Imagen , Algoritmos , Procesamiento de Imagen Asistido por Computador/métodos
20.
Acc Chem Res ; 57(2): 208-221, 2024 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-38143330

RESUMEN

Proenzymes, functioning as inactive precursor forms of enzymes, hold significant promise for regulating essential biological processes. Their inherent property of latency, remaining inert until they arrive at the intended site of action, positions them as particularly promising candidates for the development of targeted therapeutics. Despite this potential, the therapeutic potential of proenzymes is challenged by designing proenzymes with excellent selectivity for disease cells. This limitation is further exacerbated by the inability of proenzymes to spontaneously cross the cell membrane, a biological barrier that impedes the cellular internalization of exogenous macromolecules. Therefore, efficacious intracellular delivery is paramount to unlocking the full therapeutic potency of proenzymes.In this Account, we first elucidate our recent advancements made in designing biodegradable lipid nanoparticles (LNPs) for the cell-specific delivery of biomacromolecules, including proteins and nucleic acids. Using a strategy of parallel synthesis, we have constructed an extensive library of ionizable lipids, each integrated with different biodegradable moieties. This combinatorial approach has led to the identification of LNPs that are particularly efficacious for the delivery of biomacromolecules specifically to tumor cells. This innovation capitalizes on the unique intracellular environment of cancer cells to control the degradation of LNPs, thereby ensuring the targeted release of therapeutics within tumor cells. Additionally, we discuss the structure-activity relationship governing the delivery efficacy of these LNPs and their applicability in regulating tumor cell signaling, specifically through the delivery of bacterial effector proteins.In the second segment, we aim to provide an overview of our recent contributions to the field of proenzyme design, where we have chemically tailored proteins to render them responsive to the unique milieu of tumor cells. Specifically, we elaborate on the chemical principles employed to modify proteins and DNAzymes, thereby priming them for activation in the presence of NAD(P)H:quinone oxidoreductase 1 (NQO1), an enzyme that is prevalently upregulated within tumor cells. We summarize the methodologies for intracellular delivery of these proenzymes using biodegradable LNPs, both in vitro and in vivo. The concomitant intracellular delivery and activation of proenzymes are examined in the context of enhanced therapeutic outcomes and targeted CRISPR/Cas9 genome editing.In conclusion, we offer a perspective on the chemical principles that could be leveraged to optimize LNPs for tissue-specific delivery of proenzymes. We also explore chemical strategies for the irreversible modulation of proenzyme activity within living cells and in vivo. Through this discussion, we provide insights into potential avenues for overcoming existing limitations and enhancing the delivery of proenzymes using LNPs, particularly for developing tumor-targeted therapies and genome editing applications.


Asunto(s)
Precursores Enzimáticos , Nanopartículas , Liposomas , Edición Génica , Nanopartículas/química , Proteínas
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