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1.
Nature ; 626(8000): 742-745, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38383623

RESUMEN

Observationally, kilonovae are astrophysical transients powered by the radioactive decay of nuclei heavier than iron, thought to be synthesized in the merger of two compact objects1-4. Over the first few days, the kilonova evolution is dominated by a large number of radioactive isotopes contributing to the heating rate2,5. On timescales of weeks to months, its behaviour is predicted to differ depending on the ejecta composition and the merger remnant6-8. Previous work has shown that the kilonova associated with gamma-ray burst 230307A is similar to kilonova AT2017gfo (ref. 9), and mid-infrared spectra revealed an emission line at 2.15 micrometres that was attributed to tellurium. Here we report a multi-wavelength analysis, including publicly available James Webb Space Telescope data9 and our own Hubble Space Telescope data, for the same gamma-ray burst. We model its evolution up to two months after the burst and show that, at these late times, the recession of the photospheric radius and the rapidly decaying bolometric luminosity (Lbol ∝ t-2.7±0.4, where t is time) support the recombination of lanthanide-rich ejecta as they cool.

2.
Nature ; 612(7939): 232-235, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36477130

RESUMEN

It is generally believed that long-duration gamma-ray bursts (GRBs) are associated with massive star core collapse1, whereas short-duration GRBs are associated with mergers of compact star binaries2. However, growing observations3-6 have suggested that oddball GRBs do exist, and several criteria (prompt emission properties, supernova/kilonova associations and host galaxy properties) rather than burst duration only are needed to classify GRBs physically7. A previously reported long-duration burst, GRB 060614 (ref. 3), could be viewed as a short GRB with extended emission if it were observed at a larger distance8 and was associated with a kilonova-like feature9. As a result, it belongs to the type I (compact star merger) GRB category and is probably of binary neutron star (NS) merger origin. Here we report a peculiar long-duration burst, GRB 211211A, whose prompt emission properties in many aspects differ from all known type I GRBs, yet its multiband observations suggest a non-massive-star origin. In particular, substantial excess emission in both optical and near-infrared wavelengths has been discovered (see also ref. 10), which resembles kilonova emission, as observed in some type I GRBs. These observations point towards a new progenitor type of GRBs. A scenario invoking a white dwarf (WD)-NS merger with a post-merger magnetar engine provides a self-consistent interpretation for all the observations, including prompt gamma rays, early X-ray afterglow, as well as the engine-fed11,12 kilonova emission.


Asunto(s)
Rayos gamma
3.
Small ; : e2402320, 2024 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-38881259

RESUMEN

Nanozyme-mediated chemodynamic therapy has emerged as a promising strategy due to its tumor specificity and controlled catalytic activity. However, the poor efficacy caused by low hydrogen peroxide (H2O2) levels in the tumor microenvironment (TME) poses challenges. Herein, an H2O2 self-supplying nanozyme is constructed through loading peroxide-like active platinum nanoparticles (Pt NPs) on zinc peroxide (ZnO2) (denoted as ZnO2@Pt). ZnO2 releases H2O2 in response to the acidic TME. Pt NPs catalyze the hydroxyl radical generation from H2O2 while reducing the mitigation of oxidative stress by glutathione, serving as a reactive oxygen (ROS) amplifier through self-cascade catalysis. In addition, Zn2+ released from ZnO2 interferes with tumor cell energy supply and metabolism, enabling ion interference therapy to synergize with chemodynamic therapy. In vitro studies demonstrate that ZnO2@Pt induces cellular oxidative stress injury through enhanced ROS generation and Zn2+ release, downregulating ATP and NAD+ levels. In vivo assessment of anticancer effects showed that ZnO2@Pt could generate ROS at tumor sites to induce apoptosis and downregulate energy supply pathways associated with glycolysis, resulting in an 89.7% reduction in tumor cell growth. This study presents a TME-responsive nanozyme capable of H2O2 self-supply and ion interference therapy, providing a paradigm for tumor-specific nanozyme design.

4.
Plant Physiol ; 194(1): 376-390, 2023 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-37706538

RESUMEN

Rice (Oryza sativa) production consumes a huge amount of fresh water, and improvement of drought tolerance in rice is important to conserve water resources and minimize yield loss under drought. However, processes to improve drought tolerance in rice have not been fully explored, and a comparative study between rice and wheat (Triticum aestivum) is an effective method to understand the mechanisms determining drought tolerance capacity. In the present study, we applied short-term drought stress to Shanyou 63 rice and Yannong 19 wheat to create a range of water potentials and investigated the responses of gas exchange, plant hydraulic conductance, and root morphological and anatomical traits to soil drought. We found that photosynthesis in rice was more sensitive to drought stress than that in wheat, which was related to differences in the decline of stomatal conductance and plant hydraulic conductance (Kplant). The decline of Kplant under drought was mainly driven by the decrease of soil-root interface hydraulic conductance (Ki) because Ki was more sensitive to drought than root and shoot hydraulic conductance and the soil-root interface contributed to >40% of whole-plant hydraulic resistance in both crops. Root shrinkage in response to drought was more severe in rice than that in wheat, which explains the larger depression of Ki and Kplant under drought stress in rice. We concluded that the decline of Ki drives the depression of Kplant and photosynthesis in both crops, and the plasticity of root morphology and anatomy is important in determining drought tolerance capacity.


Asunto(s)
Oryza , Hojas de la Planta , Hojas de la Planta/fisiología , Suelo , Sequías , Oryza/fisiología , Triticum/fisiología , Raíces de Plantas/fisiología , Agua/fisiología , Fotosíntesis , Productos Agrícolas
5.
Langmuir ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38966998

RESUMEN

The toxic gases emitted from industrial production have caused significant damage to the environment and human health, necessitating efficient gas sensors for their detection and removal. In this work, first-principles calculations are employed to investigate the potential application of diamanes for high-performance toxic gas sensors. The results show that nine gas molecules (CO, CO2, NO, NO2, NH3, SO2, N2, O2, and H2O) are physisorbed on pristine diamane by weak van der Waals interactions. After introducing H/F defects, diamane can effectively capture specific toxic gases (CO, NO, NO2, and SO2) in the presence of interfering gases (N2, O2, and H2O), suggesting excellent selectivity and anti-interference ability. Orbital hybridization and significant charge redistribution between gas molecules and defective diamane dominate the enhanced adsorbate-substrate interactions. More importantly, the high sensitivity and good reversibility of defective diamane for detecting CO, NO, and SO2 molecules enable its reuse as a superior resistance-type gas sensor. Our calculations provide valuable insights into the potential of defective diamane for detecting toxic gases and shed light on the practical application of novel carbon-based materials in the gas-sensing field.

6.
Cell Mol Life Sci ; 80(1): 27, 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36602641

RESUMEN

The proportions of the various muscle fiber types are important in the regulation of skeletal muscle metabolism, as well as animal meat production. Four-and-a-half LIM domain protein 3 (FHL3) is highly expressed in fast glycolytic muscle fibers and differentially regulates the expression of myosin heavy chain (MyHC) isoforms at the cellular level. Whether FHL3 regulates the transformation of muscle fiber types in vivo and the regulatory mechanism is unclear. In this study, muscle-specific FHL3 transgenic mice were generated by random integration, and lentivirus-mediated gene knockdown or overexpression in muscles of mice or pigs was conducted. Functional analysis showed that overexpression of FHL3 in muscles significantly increased the proportion of fast-twitch myofibers and muscle mass but decreased muscle succinate dehydrogenase (SDH) activity and whole-body oxygen consumption. Lentivirus-mediated FHL3 knockdown in muscles significantly decreased muscle mass and the proportion of fast-twitch myofibers. Mechanistically, FHL3 directly interacted with the Yin yang 1 (YY1) DNA-binding domain, repressed the binding of YY1 to the fast glycolytic MyHC2b gene regulatory region, and thereby promoted MyHC2b expression. FHL3 also competed with EZH2 to bind the repression domain of YY1 and reduced H3K27me3 enrichment in the MyHC2b regulatory region. Moreover, FHL3 overexpression reduced glucose tolerance by affecting muscle glycolytic metabolism, and its mRNA expression in muscle was positively associated with hemoglobin A1c (HbA1c) in patients with type 2 diabetes. Therefore, FHL3 is a novel potential target gene for the treatment of muscle metabolism-related diseases and improvement of animal meat production.


Asunto(s)
Diabetes Mellitus Tipo 2 , Ratones , Porcinos , Animales , Diabetes Mellitus Tipo 2/metabolismo , Fibras Musculares de Contracción Rápida/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Glucólisis/genética , Cadenas Pesadas de Miosina/genética , Cadenas Pesadas de Miosina/metabolismo
7.
Semin Cancer Biol ; 87: 137-147, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36372326

RESUMEN

Artificial intelligence (AI) indicates the application of machines to imitate intelligent behaviors for solving complex tasks with minimal human intervention, including machine learning and deep learning. The use of AI in medicine improves health-care systems in multiple areas such as diagnostic confirmation, risk stratification, analysis, prognosis prediction, treatment surveillance, and virtual health support, which has considerable potential to revolutionize and reshape medicine. In terms of immunotherapy, AI has been applied to unlock underlying immune signatures to associate with responses to immunotherapy indirectly as well as predict responses to immunotherapy responses directly. The AI-based analysis of high-throughput sequences and medical images can provide useful information for management of cancer immunotherapy considering the excellent abilities in selecting appropriate subjects, improving therapeutic regimens, and predicting individualized prognosis. In present review, we aim to evaluate a broad framework about AI-based computational approaches for prediction of response to cancer immunotherapy on both indirect and direct manners. Furthermore, we summarize our perspectives about challenges and opportunities of further AI applications on cancer immunotherapy relating to clinical practicability.


Asunto(s)
Inteligencia Artificial , Neoplasias , Humanos , Aprendizaje Automático , Inmunoterapia , Atención a la Salud , Neoplasias/terapia
8.
Plant J ; 112(1): 221-234, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35962704

RESUMEN

Although mesophyll conductance (gm ) is known to be sensitive to temperature (T), the mechanisms underlying the temperature response of gm are not fully understood. In particular, it has yet to be established whether interspecific variation in gm -T relationships is associated with mesophyll anatomy and vein traits. In the present study, we measured the short-term response of gm in eight crop species, and leaf water potential (Ψleaf ) in five crop species over a temperature range of 15-35°C. The considered structural parameters are surface areas of mesophyll cells and chloroplasts facing intercellular airspaces per unit leaf area (Sm and Sc ), cell wall thickness (Tcw ), and vein length per area (VLA). We detected large interspecific variations in the temperature responses of gm and Ψleaf . The activation energy for gm (Ea,gm ) was found to be positively correlated with Sc , although it showed no correlation with Tcw . In contrast, VLA was positively correlated with the slope of the linear model of Ψleaf -T (a), whereas Ea,gm was marginally correlated with VLA and a. A two-component model was subsequently used to model gm -T relationships, and the mechanisms underlying the temperature response of gm are discussed. The data presented here indicate that leaf anatomy is a major determinant of the interspecific variation in gm -T relationships.


Asunto(s)
Células del Mesófilo , Fotosíntesis , Dióxido de Carbono , Células del Mesófilo/fisiología , Hojas de la Planta/fisiología , Temperatura , Agua
9.
J Am Chem Soc ; 145(16): 9233-9241, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37043290

RESUMEN

A new strategy focusing on the last-stage asymmetric assembly of the ring D, which inherently possesses the densest part of stereogenic centers and functional groups in the A/B/C/D ring system of (-)-cephalotaxine, has been developed, in which a novel Rh-catalyzed asymmetric (2 + 3) annulation of tertiary enamides with enoldiazoacetates is designed and explored for enantioselective construction of the crucial cyclopentane ring D bearing a unique spirocyclic aza-quaternary stereocenter. Based on the expeditious access of chiral functionalized building block with the tetracyclic A/B/C/D ring system, a concise enantioselective total synthesis of (-)-cephalotaxine starting from readily available homopiperonyl alcohol has been achieved in nine steps with only two column chromatography purifications. Following the tactical introduction of the Meinwald rearrangement, enantioselective divergent syntheses of (-)-cephalotine B with an additional C3-O-C11 oxo-bridged bond (14 steps), (-)-fortuneicyclidin B with an unprecedented C3-C10 bond (14 steps), and its 2-epimer (-)-fortuneicyclidin A (16 steps) have been also accomplished for the first time.

10.
J Transl Med ; 21(1): 526, 2023 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-37542324

RESUMEN

Primary liver cancer is one of the most common malignant tumours worldwide; it caused approximately 830,000 deaths in 2020. Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer, accounting for over 80% of all cases. Various methods, including surgery, chemotherapy, radiotherapy, and radiofrequency ablation, have been widely used in the treatment of HCC. With the advancement of technology, radiotherapy has become increasingly important in the comprehensive treatment of HCC. However, due to the insufficient sensitivity of tumour cells to radiation, there are still multiple limitation in clinical application of radiotherapy. In recent years, the role of immunotherapy in cancer has been increasingly revealed, and more researchers have turned their attention to the combined application of immunotherapy and radiotherapy in the hope of achieving better treatment outcomes. This article reviews the progress on radiation therapy in HCC and the current status of its combined application with immunotherapy, and discusses the prospects and value of radioimmunotherapy in HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Inmunoterapia , Resultado del Tratamiento
11.
J Transl Med ; 21(1): 302, 2023 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-37147666

RESUMEN

BACKGROUND: Epithelial-to-mesenchymal transition (EMT) and cancer stem-like cells (CSLCs) play crucial role in tumor metastasis and drug-resistance. Disheveled3 (DVL3) is involved in malignant behaviors of cancer. However, the role and potential mechanism of DVL3 remain elusive in EMT and CSLCs of colorectal cancer (CRC). METHODS: UALCAN and PrognoScan databases were employed to evaluate DVL3 expression in CRC tissues and its correlation with CRC prognosis, respectively. Transwell, sphere formation and CCK8 assay were used to assess metastasis, stemness and drug sensitivity of CRC cells, respectively. Western blotting and dual luciferase assay were performed to analyze the protein expression and Wnt/ß-catenin activation, respectively. Lentiviral transfection was used to construct the stable cell lines. Animal studies were performed to analyze the effect of silencing DVL3 on tumorigenicity and metastasis of CRC cells in vivo. RESULTS: DVL3 was overexpressed in CRC tissues and several CRC cell lines. DVL3 expression was also higher in CRC tissues with lymph node metastasis than tumor tissues without metastasis, and correlated with poor prognosis of CRC patients. DVL3 positively regulated the abilities of migration, invasion and EMT-like molecular changes in CRC cells. Moreover, DVL3 promoted CSLCs properties and multidrug resistance. We further identified that Wnt/ß-catenin was crucial for DVL3-mediated EMT, stemness and SOX2 expression, while silencing SOX2 inhibited DVL3-mediated EMT and stemness. Furthermore, c-Myc, a direct target gene of Wnt/ß-catenin, was required for SOX2 expression and strengthened EMT and stemness via SOX2 in CRC cells. Finally, knockdown of DVL3 suppressed tumorigenicity and lung metastasis of CRC cells in nude mice. CONCLUSION: DVL3 promoted EMT and CSLCs properties of CRC via Wnt/ß-catenin/c-Myc/SOX2 axis, providing a new strategy for successful CRC treatment.


Asunto(s)
Neoplasias Colorrectales , Proteínas Dishevelled , Transición Epitelial-Mesenquimal , Vía de Señalización Wnt , beta Catenina , Animales , Ratones , beta Catenina/metabolismo , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Neoplasias Colorrectales/patología , Regulación Neoplásica de la Expresión Génica , Ratones Desnudos , Humanos , Proteínas Dishevelled/genética , Células Madre Neoplásicas
12.
BMC Cancer ; 23(1): 789, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37612627

RESUMEN

This study aimed to evaluate the potential of exosomes from cancer cells to predict chemoresistance in pancreatic cancer (PC) and explore the molecular mechanisms through RNA-sequencing and mass spectrometry. We sought to understand the connection between the exosomal Medium-chain acyl-CoA dehydrogenase (ACADM) level and the reaction to gemcitabine in vivo and in patients with PC. We employed loss-of-function, gain-of-function, metabolome mass spectrometry, and xenograft models to investigate the effect of exosomal ACADM in chemoresistance in PC. Our results showed that the molecules involved in lipid metabolism in exosomes vary between PC cells with different gemcitabine sensitivity. Exosomal ACADM (Exo-ACADM) was strongly correlated with gemcitabine sensitivity in vivo, which can be used as a predictor for postoperative gemcitabine chemosensitivity in pancreatic patients. Moreover, ACADM was found to regulate the gemcitabine response by affecting ferroptosis through Glutathione peroxidase 4 (GPX4) and mevalonate pathways. It was also observed that ACADM increased the consumption of unsaturated fatty acids and decreased intracellular lipid peroxides and reactive oxygen species (ROS) levels. In conclusion, this research suggests that Exo-ACADM may be a viable biomarker for predicting the responsiveness of patients to chemotherapy.


Asunto(s)
Ferroptosis , Neoplasias Pancreáticas , Humanos , Acil-CoA Deshidrogenasa , Gemcitabina , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Metabolismo de los Lípidos , Ácidos Grasos , Neoplasias Pancreáticas
13.
Nat Chem Biol ; 17(8): 915-923, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33958793

RESUMEN

Plant-based photosensors, such as the light-oxygen-voltage sensing domain 2 (LOV2) from oat phototropin 1, can be modularly wired into cell signaling networks to remotely control protein activity and physiological processes. However, the applicability of LOV2 is hampered by the limited choice of available caging surfaces and its preference to accommodate the effector domains downstream of the C-terminal Jα helix. Here, we engineered a set of LOV2 circular permutants (cpLOV2) with additional caging capabilities, thereby expanding the repertoire of genetically encoded photoswitches to accelerate the design of optogenetic devices. We demonstrate the use of cpLOV2-based optogenetic tools to reversibly gate ion channels, antagonize CRISPR-Cas9-mediated genome engineering, control protein subcellular localization, reprogram transcriptional outputs, elicit cell suicide and generate photoactivatable chimeric antigen receptor T cells for inducible tumor cell killing. Our approach is widely applicable for engineering other photoreceptors to meet the growing need of optogenetic tools tailored for biomedical and biotechnological applications.


Asunto(s)
Proteínas de Arabidopsis/genética , Proteínas de Unión al ADN/genética , Ingeniería Genética , Optogenética , Animales , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Células Cultivadas , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , Femenino , Humanos , Ratones , Ratones Endogámicos NOD , Ratones Transgénicos , Procesos Fotoquímicos
14.
Environ Sci Technol ; 57(38): 14150-14161, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37699525

RESUMEN

Exposure to ambient fine particulate matter (PM2.5) is associated with millions of premature deaths annually. Oxidative stress through overproduction of reactive oxygen species (ROS) is a possible mechanism for PM2.5-induced health effects. Organic aerosol (OA) is a dominant component of PM2.5 worldwide, yet its role in PM2.5 toxicity is poorly understood due to its chemical complexity. Here, through integrated cellular ROS measurements and detailed multi-instrument chemical characterization of PM in urban southeastern United States, we show that oxygenated OA (OOA), especially more-oxidized OOA, is the main OA type associated with cellular ROS production. We further reveal that highly unsaturated species containing carbon-oxygen double bonds and aromatic rings in OOA are major contributors to cellular ROS production. These results highlight the key chemical features of ambient OA driving its toxicity. As more-oxidized OOA is ubiquitous and abundant in the atmosphere, this emphasizes the need to understand its sources and chemical processing when formulating effective strategies to mitigate PM2.5 health impacts.


Asunto(s)
Estrés Oxidativo , Oxígeno , Especies Reactivas de Oxígeno , Aerosoles , Sudeste de Estados Unidos
15.
Exp Cell Res ; 421(2): 113402, 2022 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-36328194

RESUMEN

Aberrant ubiquitin-proteasome system (UPS) contributes to tumorigeneisis or drug resistance of Pancreatic Adenocarcinoma (PAAD). Previous studies have implicated the deubiquitinase UCHL5 was abnormally expressed in multiple malignancies. However, little was reported about the specific roles of UCHL5 in PAAD. We aimed to identify the biological roles of UCHL5 in PAAD and demonstrate its prognostic significance. Differential analysis revealed that UCHL5 expressed highly in tumors versus normal tissues, like TCGA-PAAD, GSE28735, GSE15471 and collected samples. Patients with high UCHL5 expressions had worse survival outcomes relative to those with low UCHL5 levels. Experimental assays showed that UCHL5 overexpression could significantly enhance cell proliferation, colony formation and self-renewal capacities. UCHL5 could also promote PAAD migration in vitro and in vivo. Mechanistically, UCHL5 could directly deubiquitinate and stabilize ELK3 proteins. UCHL5 relied on accumulated ELK3 proteins to drive cell growth, stem-like properties and migration abilities. In addition, enrichment analysis based on RNA-seq data implicated that ELK3 mainly correlated with Notch1 signaling and ELK3 could notably elevate ELK3 mRNA levels. UCHL5 could thus promote self-renewal abilities of PAAD and targeting ELK3 could inhibit the stemness features. In contrast, UCHL5 deficiency could suppress PAAD stemness features, and ectopic expression of ELK3 could rescue this effect. Last of all, we utilized the UCHL5 inhibitor, b-AP15, to treat PAAD cells and found that b-AP15 could inhibit the growth of PAAD cells in a dose-dependent manner. Collectively, our study uncovered the underlying mechanisms of UCHL5/ELK3/Notch1 axis in PAAD progression and stemness maintaince, shedding light on individualized treatment and risk stratification for PAAD patients.


Asunto(s)
Adenocarcinoma , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/patología , Adenocarcinoma/patología , Proliferación Celular/genética , Ubiquitina Tiolesterasa/genética , Ubiquitina Tiolesterasa/metabolismo , Proteínas Proto-Oncogénicas c-ets , Neoplasias Pancreáticas
16.
Bioorg Chem ; 135: 106485, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36963370

RESUMEN

Small interfering RNA (siRNA) can be exploited to silence specific genes associated with cancer development, and successful siRNA therapy is highly dependent on the efficiency of the siRNA delivery vector. Herein, a well-designed novel redox- and enzyme-responsive fluorinated polyarginine (PFC-PR) was developed to be used as an anti-cancer siRNA carrier. The multiple guanidine groups could provide positive charges and bind with siRNA efficiently, and further fluorination modification enhanced the interaction with siRNA, resulting in a more stable PFC-PR/siRNA nanocomplex, improving serum tolerance, and promoting cellular uptake and endosome escape. Meanwhile, the PFC-PR was responsive to overexpressed cathepsin B and high levels of glutathione in cancer cells, conferring its ability to enhance siRNA release within cancer cells and making it cancer-targeting. Consequently, PFC-PR showed good biocompatibility and high gene silencing efficiency, which could inhibit cancer cell growth when delivered the siRNA targeting vascular endothelial growth factor, suggesting that it can be potentially used for anti-cancer gene therapy applications.


Asunto(s)
Neoplasias , Factor A de Crecimiento Endotelial Vascular , Humanos , ARN Interferente Pequeño/farmacología , ARN Interferente Pequeño/genética , Factor A de Crecimiento Endotelial Vascular/genética , Catepsina B/genética , Péptidos , Neoplasias/terapia , Glutatión , Línea Celular Tumoral
17.
Eur J Pediatr ; 182(10): 4365-4368, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37462798

RESUMEN

Hepatic hemangioma (HH) and hepatoblastoma (HBL) are common pediatric liver tumors and present with similar clinical manifestations with limited distinguishing value of serum AFP in early infancy. An accurate differentiation diagnostic tool is warranted for optimizing treatments and improving prognosis. The present study aimed to develop an innovative and cost-effective diagnostic tool to differentiate HH and HBL in early infancy using advanced deep learning (DL) techniques. One hundred forty patients ≤4 months old diagnosed as HH or HBL with histological specimens were recruited from two institutions assigned into a training set with cross-validation and a testing set for external validation, respectively. Based on MRI images, imaging diagnoses were interpreted by two radiologists, and imaging-derived radiomic features were extracted by pretrained convolutional neural networks (CNNs)-Xception extractor via DL analysis. A nomogram model was constructed integrating predictive clinical variables, radiologist-based interpretation, and DL features, evaluated comprehensively on diagnostic and calibration accuracy. The DL-based model performed an area under the receiver operating characteristic curve (AUC) of 0.966 for the training cohort and 0.864 for the testing cohort. The radiologist-interpreted differentiation model showed an AUC of 0.837 in the testing cohort. The integrated nomogram model represented an increasing performance with an AUC of 0.887, accuracy of 78.57%, sensitivity of 76.19%, and specificity of 80.95% in the testing cohort. CONCLUSION:  The MRI-based integrated model, a noninvasive preoperative diagnostic tool, yielded favorable efficacy for differentiating HH and HBL in early infancy, which might reduce the patients' costs of repetitive and unnecessary examinations or over-treatment. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05170282. WHAT IS KNOWN: • Hepatic hemangioma (HH) and hepatoblastoma (HBL) are common pediatric liver tumors and present with similar clinical manifestations with limited distinguishing value of serum AFP in early infancy. • Considering the rare incidence of infantile hepatic tumors, the distinguishing accuracy between HBL and HH for cases in early infancy is unsatisfactory for radiologists' recognition solely. WHAT IS NEW: • The MRI-based integrated model, a noninvasive preoperative diagnostic tool yielded favorable efficacy for differentiating HH and HBL in early infancy, which might reduce the patients' costs of repetitive and unnecessary examinations or over-treatment.


Asunto(s)
Aprendizaje Profundo , Hemangioma , Hepatoblastoma , Neoplasias Hepáticas , Niño , Humanos , Lactante , Preescolar , Hepatoblastoma/diagnóstico por imagen , alfa-Fetoproteínas , Neoplasias Hepáticas/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Hemangioma/diagnóstico por imagen , Estudios Retrospectivos
18.
Environ Toxicol ; 38(12): 2894-2903, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37551626

RESUMEN

BACKGROUND: Cancer stem cells (CSCs) play a key role in tumor cell growth, drug resistance, recurrence, and metastasis. Proanthocyanidins (PC) is widely existed in plants and endowed with powerful antioxidant and anti-aging effects. Interestingly, recent studies have found that PC exhibits the inhibitory effect on tumor growth. However, the role of PC in CSCs of colorectal cancer (CRC) and molecular mechanism remain unclear. METHODS: CCK-8, colony, and tumorsphere formation assay were used to evaluate cancer cell viability and stemness, respectively. Western blotting was used to detect the protein expression. Tumor xenograft experiments were employed to examine the tumorigenicity of CRC cells in nude mice. RESULTS: PC decreased the proliferation of CRC cells (HT29 and HCT-116), and improved the sensitivity of CRC cells to oxaliplatin (L-OHP), as well as inhibited tumor growth in nude mice. Further studies showed that PC also down-regulated CSCs surface molecular and stemness transcriptional factors, while suppressed the formations of tumorspheres and cell colony in CRC. In addition, PC-impaired proteins expressions of p-GSK3ß, ß-catenin and DVL1-3. LiCl, an activator of the Wnt/ß-catenin signaling, rescued PC-induced downregulation of CSCs markers, and reduction of tumorspheres and cell colony formation abilities in CRC cells. Furthermore, the effects of PC on inhibiting cell proliferation and enhancing L-OHP sensitivity were impaired by LiCl. CONCLUSIONS: PC exerted an inhibitory effect on CSCs via Wnt/ß-catenin in CRC, and may be a potential new class of natural drug for CRC treatment.


Asunto(s)
Neoplasias Colorrectales , Proantocianidinas , Animales , Ratones , Humanos , Línea Celular Tumoral , Ratones Desnudos , Proantocianidinas/farmacología , Proantocianidinas/metabolismo , Proantocianidinas/uso terapéutico , beta Catenina/metabolismo , Neoplasias Colorrectales/genética , Células Madre Neoplásicas/metabolismo , Proliferación Celular , Regulación Neoplásica de la Expresión Génica
19.
Sensors (Basel) ; 23(22)2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-38005609

RESUMEN

During the measurement of magnetic fields, Residence Time Difference (RTD)-fluxgate sensors suffer from abnormal time difference jumps due to the random interference of magnetic core noise and environmental noise, which results in gross errors. This situation restricts the improvement of sensor accuracy and stability. In order to solve the above problems efficiently, a time difference gross error processing method based on the combination of the Mahalanobis distance (MD) and group covariance is presented in this paper, and the processing effects of different methods are compared and analyzed. The results of the simulation and experiment indicate that the proposed method is more advantageous in identifying the gross error in time difference. The signal-to-noise ratio for the time difference is improved by about 34 times, while the fluctuation of the Negative Magnetic Saturation Time (NMST) ΔTNMST is reduced by 95.402%, which significantly reduces the fluctuation of time difference and effectively improves the accuracy and stability of the sensor.

20.
Drug Dev Res ; 84(5): 988-998, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37132439

RESUMEN

Colorectal cancer (CRC) is a common tumor with high morbidity and mortality. The use of oxaliplatin (L-OHP) as a first-line treatment for CRC is limited due to chemoresistance. Growing evidence have revealed that the existence of cancer stem-like cells (CSLCs) is one of the important reasons for drug resistance and recurrence of cancers. Dihydroartemisinin (DHA), a derivative of artemisinin, has showed anticancer effects on a variety of malignancies, in addition to its antimalarial effects. However, the effect and mechanism of DHA on CSLCs and chemosensitivity in CRC cells remains unclear. In this study, we found that DHA inhibited cell viability in HCT116 and SW620 cells. Moreover, DHA decreased cell clonogenicity, and improved L-OHP sensitivity. Furthermore, DHA treatment attenuated tumor sphere formation, and the expressions of stem cell surface marker (CD133 and CD44) and stemness-associated transcription factor (Nanog, c-Myc, and OCT4). Mechanistically, the present findings showed that DHA inhibited of AKT/mTOR signaling pathway. The activation of AKT/mTOR signaling reversed DHA-decreased cell viability, clonogenicity, L-OHP resistance, tumor sphere, and expressions of stemness-associated protein in CRC. The inhibitory effect of DHA on tumorigenicity of CRC cells has also been demonstrated in BALB/c nude mice. In conclusion, this study revealed that DHA inhibited CSLCs properties in CRC via AKT/mTOR signaling, suggesting that DHA may be used as a potential therapeutic agent for CRC.


Asunto(s)
Neoplasias Colorrectales , Proteínas Proto-Oncogénicas c-akt , Animales , Ratones , Oxaliplatino/farmacología , Oxaliplatino/uso terapéutico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/metabolismo , Ratones Desnudos , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo , Células Madre Neoplásicas , Línea Celular Tumoral , Proliferación Celular
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