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1.
Molecules ; 29(7)2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38611715

RESUMEN

The plant-derived toxin ricin is classified as a type 2 ribosome-inactivating protein (RIP) and currently lacks effective clinical antidotes. The toxicity of ricin is mainly due to its ricin toxin A chain (RTA), which has become an important target for drug development. Previous studies have identified two essential binding pockets in the active site of RTA, but most existing inhibitors only target one of these pockets. In this study, we used computer-aided virtual screening to identify a compound called RSMI-29, which potentially interacts with both active pockets of RTA. We found that RSMI-29 can directly bind to RTA and effectively attenuate protein synthesis inhibition and rRNA depurination induced by RTA or ricin, thereby inhibiting their cytotoxic effects on cells in vitro. Moreover, RSMI-29 significantly reduced ricin-mediated damage to the liver, spleen, intestine, and lungs in mice, demonstrating its detoxification effect against ricin in vivo. RSMI-29 also exhibited excellent drug-like properties, featuring a typical structural moiety of known sulfonamides and barbiturates. These findings suggest that RSMI-29 is a novel small-molecule inhibitor that specifically targets ricin toxin A chain, providing a potential therapeutic option for ricin intoxication.


Asunto(s)
Ricina , Animales , Ratones , Proteínas Inactivadoras de Ribosomas Tipo 2 , Desarrollo de Medicamentos , Hidrolasas , Hígado
2.
RSC Adv ; 14(7): 4543-4555, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38312726

RESUMEN

Due to their high wavelength selectivity and strong anti-interference capability, solar-blind UV photodetectors hold broad and important application prospects in fields like flame detection, missile warnings, and secure communication. Research on solar-blind UV detectors for amorphous Ga2O3 is still in its early stages. The presence of intrinsic defects related to oxygen vacancies significantly affects the photodetection performance of amorphous Ga2O3 materials. This paper focuses on growing high quality amorphous Ga2O3 films on silicon substrates through atomic layer deposition. The study investigates the impact of annealing atmospheres on Ga2O3 films and designs a blind UV detector for Ga2O3. Characterization techniques including atomic force microscopy (AFM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) are used for Ga2O3 film analysis. Ga2O3 films exhibit a clear transition from amorphous to polycrystalline after annealing, accompanied by a decrease in oxygen vacancy concentration from 21.26% to 6.54%. As a result, the response time of the annealed detector reduces from 9.32 s to 0.47 s at an external bias of 10 V. This work demonstrates that an appropriate annealing process can yield high-quality Ga2O3 films, and holds potential for advancing high-performance solar blind photodetector (SBPD) development.

3.
Artículo en Inglés | MEDLINE | ID: mdl-37906413

RESUMEN

The lipopeptides produced by Bacillus subtilis have anti-cancer potential. We had previously identified a secondary metabolite of B. subtilis strain Z15 (BS-Z15), which has an operon that regulates lipopeptide synthesis, and also demonstrated that the fermentation products of this strain exerted antioxidant and pro-immune effects. The purpose of this study was to investigate in vitro and in vivo the anticancer effects of BS-Z15 secondary metabolites (BS-Z15 SMs) on hepatocellular carcinoma (HCC) cells. BS-Z15 SMs significantly inhibited H22 cell-derived murine xenograft tumor growth without any systemic toxicity. In addition, BS-Z15 SMs decreased the viability of H22 cells and BEL-7404 cells in vitro with respective IC50 values of 33.83 and 27.26 µg/mL. Consistent with this, BS-Z15 SMs induced apoptosis and G0/G1 phase arrest in the BEL-7404 cells, and the mitochondrial membrane potential was also significantly reduced in a dose-dependent manner. Mechanistically, BS-Z15 SMs upregulated the pro-apoptotic p53, Bax, cytochrome C, and cleaved-caspase-3/9 proteins and downregulated the anti-apoptotic Bcl-2. These findings suggest that the induction of apoptosis in HCC cells by BS-Z15 SMs may be related to the mitochondrial pathway. Thus, the secondary metabolites of B. subtilis strain Z15 are promising to become new anti-cancer drugs for the clinical treatment of liver cancer.

4.
Comput Struct Biotechnol J ; 21: 4056-4069, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37664172

RESUMEN

Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is one of the most prominent housekeeping proteins and is widely used as an internal control in some semi-quantitative assays. In addition to glycolysis, GAPDH is involved in several cancer-related biological processes and has been reported to be commonly dysregulated in multiple cancer types. Therefore, its role in the physiological process of cancer needs to be urgently elucidated. Pan-cancer analysis indicated that GAPDH is ubiquitously highly expressed in most cancer types, and that patients with a high GAPDH expression of in tumor tissues have a poor prognosis. The concordance of GAPDH expression in tumors with the infiltration of immune cells and immune checkpoints implies a certain association between GAPDH and the tumor microenvironment as well as tumor development. Gene Set Enrichment Analysis revealed that GAPDH may contribute to multiple important cancer-related pathways and biological processes. Multi-omics analysis and in vitro cell experiments revealed that GAPDH overexpression is regulated by DNA copy number amplification and promoter methylation modification. Importantly, a transcription factor, forkhead box M1 (FOXM1), which is capable of regulating GAPDH expression, was also identified and was confirmed to be an oncogene and ubiquitously highly expressed in multiple cancer types. Semi-quantitative chromatin immunoprecipitation, quantitative PCR, and dual-luciferase assays showed that FOXM1 mainly binds to the promoter region of GAPDH in two cancer cell lines. The present findings revealed the implication of GAPDH in tumor development, thus bringing attention to this important molecule and casting doubts on its role as an internal reference gene in cancer studies.

6.
BMC Genomics ; 24(1): 273, 2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37208602

RESUMEN

BACKGROUND: Previous studies have shown that secondary metabolites of Bacillus subtilis strain Z15 (BS-Z15) are effective in treating fungal infections in mice. To evaluate whether it also modulates immune function in mice to exert antifungal effects, we investigated the effect of BS-Z15 secondary metabolites on both the innate and adaptive immune functions of mice, and explored its molecular mechanism through blood transcriptome analysis. RESULTS: The study showed that BS-Z15 secondary metabolites increased the number of monocytes and platelets in the blood, improved natural killer (NK) cell activity and phagocytosis of monocytes-macrophages, increased the conversion rate of lymphocytes in the spleen, the number of T lymphocytes and the antibody production capacity of mice, and increased the levels of Interferon gamma (IFN-γ), Interleukin-6 (IL-6), Immunoglobulin G (IgG) and Immunoglobulin M (IgM) in plasma. The blood transcriptome analysis revealed 608 differentially expressed genes following treatment with BS-Z15 secondary metabolites, all of which were significantly enriched in the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) terms for immune-related entries and pathways such as Tumor Necrosis Factor (TNF) and Toll-like receptor (TLR) signaling pathways, and upregulated expression levels of immune-related genes such as Complement 1q B chain (C1qb), Complement 4B (C4b), Tetracyclin Resistant (TCR) and Regulatory Factor X, 5 (RFX5). CONCLUSIONS: BS-Z15 secondary metabolites were shown to enhance innate and adaptive immune function in mice, laying a theoretical foundation for its development and application in the field of immunity.


Asunto(s)
Bacillus subtilis , Células Asesinas Naturales , Animales , Ratones , Células Asesinas Naturales/metabolismo , Linfocitos T/metabolismo , Interferón gamma , Fagocitosis
7.
Probiotics Antimicrob Proteins ; 15(3): 706-715, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-35029788

RESUMEN

In our previous study, we identified a metabolite of Bacillus subtilis BS-Z15 (a strain with probiotic characteristics) that could improve immunity in mice. In the present study, we examined the effects of B. subtilis BS-Z15 and its metabolites on body weight gain and the intestinal microbiota of mice. Sixty 25-day-old male Kunming white mice were selected and randomly divided into four groups: control group (A), daily saline gavage; B. subtilis-treated group (B), single gavage (1 × 109 CFU/time/animal/day); group D, 14 consecutive gavages (1 × 109 CFU/time/animal/day); and B. subtilis metabolite-treated group (E), 30 consecutive gavages (90 mg kg-1/time/animal/day). High-throughput sequencing technology was used to analyze intergroup differences in the mouse intestinal microbiota. The results showed that the three treated groups had significantly slower body weight gain compared with the control group, which lasted until the 45 days (P < 0.05), and the daily food intake of the treated mice was higher (P < 0.05). The intestinal microbiota structure of the mice in the treated groups was significantly altered compared with that in the control group, suggesting that B. subtilis BS-Z15 may regulate the weight gain of animals by affecting their intestinal bacterial composition. After stopping the gavage of B. subtilis BS-Z15, the abundance of this strain in the small intestine of the mice gradually decreased and its presence was undetectable at 45 days, indicating that B. subtilis BS-Z15 could not colonize the intestine of these mice. These findings suggest that B. subtilis BS-Z15 may regulate intestinal microbiota through its metabolites to reduce weight gain.


Asunto(s)
Microbioma Gastrointestinal , Probióticos , Ratones , Masculino , Animales , Bacillus subtilis/fisiología , Intestinos/microbiología , Aumento de Peso , Probióticos/farmacología , Dieta
8.
Mol Cancer ; 21(1): 229, 2022 12 30.
Artículo en Inglés | MEDLINE | ID: mdl-36581942

RESUMEN

RATIONALE: Lung cancer is the most prevalent form of cancer and has a high mortality rate, making it a global public health concern. The N6-methyladenosine (m6A) modification is a highly dynamic and reversible process that is involved in a variety of essential biological processes. Using in vitro, in vivo, and multi-omics bioinformatics, the present study aims to determine the function and regulatory mechanisms of the long non-coding (lnc)RNA zinc ribbon domain-containing 1-antisense 1 (ZNRD1-AS1). METHODS: The RNAs that were bound to the m6A 'reader' were identified using YTH domain-containing 2 (YTHDC2) RNA immunoprecipitation (RIP)-sequencing. Utilizing methylated RIP PCR/quantitative PCR, pull-down, and RNA stability assays, m6A modification and ZNRD1-AS1 regulation were analyzed. Using bioinformatics, the expression levels and clinical significance of ZNRD1-AS1 in lung cancer were evaluated. Using fluorescent in situ hybridization and quantitative PCR assays, the subcellular location of ZNRD1-AS1 was determined. Using cell migration, proliferation, and angiogenesis assays, the biological function of ZNRD1-AS1 in lung cancer was determined. In addition, the tumor suppressor effect of ZNRD1-AS1 in vivo was validated using a xenograft animal model. Through bioinformatics analysis and in vitro assays, the downstream microRNAs (miRs) and competing endogenous RNAs were also predicted and validated. RESULTS: This study provided evidence that m6A modification mediates YTHDC2-mediated downregulation of ZNRD1-AS1 in lung cancer and cigarette smoke-exposed cells. Low levels of ZNRD1-AS1 expression were linked to adverse clinicopathological characteristics, immune infiltration, and prognosis. ZNRD1-AS1 overexpression was shown to suppress lung cancer cell proliferation, migration, and angiogenesis in vitro and in vivo, and to reduce tumor growth in nude mice. ZNRD1-AS1 expression was shown to be controlled by treatment of cells with either the methylation inhibitor 3-Deazaadenosine or the demethylation inhibitor Meclofenamic. Furthermore, the miR-942/tensin 1 (TNS1) axis was demonstrated to be the downstream regulatory signaling pathway of ZNRD1-AS1. CONCLUSIONS: ZNRD1-AS1 serves an important function and has clinical relevance in lung cancer. In addition, the findings suggested that m6A modification could mediate the regulation of the ZNRD1-AS1/miR-942/TNS1 axis via the m6A reader YTHDC2.


Asunto(s)
Neoplasias Pulmonares , MicroARNs , ARN Largo no Codificante , Animales , Ratones , Humanos , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Ratones Desnudos , Zinc/metabolismo , Hibridación Fluorescente in Situ , Línea Celular Tumoral , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias Pulmonares/genética , Movimiento Celular/genética , Pulmón/metabolismo , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , ARN Helicasas/genética , Tensinas/genética , Tensinas/metabolismo
9.
Nanomaterials (Basel) ; 12(19)2022 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-36234607

RESUMEN

Fano resonance, which is based on a plasmonic metasurface, has many potential applications in various fields, such as biochemical sensors, slow light effect, and integrated optical circuits. In this study, a rectangular-like nanotetramer metasurface structure composed of four round-head nanorods was designed. The transmission spectrum, surface charge, and electrical field distributions of the proposed structure were simulated using the finite element method. A double Fano resonance profile was observed in the transmission spectrum. One of the Fano resonances was caused by the symmetry breaking and plasmon hybridization between the horizontal double rods, whereas the other resonance was due to the plasmonic modes' hybridization among four nanorods. These resonances could be independently tuned because of different formation mechanisms. The number of Fano resonances could be adjusted by changing the coupling distance between the horizontal and vertical rods. The results contributed to designing the highly sensitive sensors based on the plasmonic metasurface.

10.
Micromachines (Basel) ; 13(10)2022 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-36295945

RESUMEN

A plasmonic refractive index sensor based on surface plasmon polaritons (SPPs) that consist of metal-insulator-metal (MIM) waveguides and a whistle-shaped cavity is proposed. The transmission properties were simulated numerically by using the finite element method. The Fano resonance phenomenon can be observed in their transmission spectra, which is due to the coupling of SPPs between the transmission along the clockwise and anticlockwise directions. The refractive index-sensing properties based on the Fano resonance were investigated by changing the refractive index of the insulator of the MIM waveguide. Modulation of the structural parameters on the Fano resonance and the optics transmission properties of the coupled structure of two MIM waveguides with a whistle-shaped cavity were designed and evaluated. The results of this study will help in the design of new photonic devices and micro-sensors with high sensitivity, and can serve as a guide for future application of this structure.

11.
Micromachines (Basel) ; 13(4)2022 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-35457806

RESUMEN

Tongue diagnosis is an important part of the diagnostic process in traditional Chinese medicine (TCM). It primarily relies on the expertise and experience of TCM practitioners in identifying tongue features, which are subjective and unstable. We proposed a tongue feature classification framework based on convolutional neural networks to reduce the differences in diagnoses among TCM practitioners. Initially, we used our self-designed instrument to capture 482 tongue photos and created 11 data sets based on different features. Then, the tongue segmentation task was completed using an upgraded facial landmark detection method and UNET. Finally, we used ResNet34 as the backbone to extract features from the tongue photos and classify them. Experimental results show that our framework has excellent results with an overall accuracy of over 86 percent and is particularly sensitive to the corresponding feature regions, and thus it could assist TCM practitioners in making more accurate diagnoses.

12.
Micromachines (Basel) ; 14(1)2022 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-36677112

RESUMEN

Gastric cancer has become a global health issue, severely disrupting daily life. Early detection in gastric cancer patients and immediate treatment contribute significantly to the protection of human health. However, routine gastric cancer examinations carry the risk of complications and are time-consuming. We proposed a framework to predict gastric cancer non-invasively and conveniently. A total of 703 tongue images were acquired using a bespoke tongue image capture instrument, then a dataset containing subjects with and without gastric cancer was created. As the images acquired by this instrument contain non-tongue areas, the Deeplabv3+ network was applied for tongue segmentation to reduce the interference in feature extraction. Nine tongue features were extracted, relationships between tongue features and gastric cancer were explored by using statistical methods and deep learning, finally a prediction framework for gastric cancer was designed. The experimental results showed that the proposed framework had a strong detection ability, with an accuracy of 93.6%. The gastric cancer prediction framework created by combining statistical methods and deep learning proposes a scheme for exploring the relationships between gastric cancer and tongue features. This framework contributes to the effective early diagnosis of patients with gastric cancer.

13.
Int J Biol Sci ; 17(10): 2633-2651, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34326699

RESUMEN

Lung cancer is one of the most common types of carcinoma worldwide. Cigarette smoking is considered the leading cause of lung cancer. Aberrant expression of several YT521-B homology (YTH) family proteins has been reported to be closely associated with multiple cancer types. The present study aims to evaluate the function and regulatory mechanisms of the N6-methyladenosine (m6A) reader protein YTH domain containing 2 (YTHDC2) by in vitro, in vivo and bioinformatics analyses. The results revealed that YTHDC2 was reduced in lung cancer and cigarette smoke-exposed cells. Notably, bioinformatics and tissue arrays analysis demonstrated that decreased YTHDC2 was highly associated with smoking history, pathological stage, invasion depth, lymph node metastasis and poor outcomes. The in vivo and in vitro studies revealed that YTHDC2 overexpression inhibited the proliferation and migration of lung cancer cells as well as tumor growth in nude mice. Furthermore, YTHDC2 decreased expression was modulated by copy number deletion in lung cancer. Importantly, the cylindromatosis (CYLD)/NF-κB pathways were confirmed as the downstream signaling of YTHDC2, and this axis was mediated by m6A modification. The present results indicated that smoking-related downregulation of YTHDC2 was associated with enhanced proliferation and migration in lung cancer cells, and appeared to be regulated by DNA copy number variation. Importantly, YTHDC2 functions as a tumor suppressor through the CYLD/NF-κB signaling pathway, which is mediated by m6A modification.


Asunto(s)
Enzima Desubiquitinante CYLD/metabolismo , Neoplasias Pulmonares/genética , Subunidad p50 de NF-kappa B/metabolismo , ARN Helicasas/metabolismo , Animales , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Variaciones en el Número de Copia de ADN , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pulmonares/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , ARN Helicasas/genética , Transducción de Señal , Ensayos Antitumor por Modelo de Xenoinjerto
14.
Opt Express ; 28(21): 30606-30615, 2020 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-33115058

RESUMEN

We demonstrate a new electromagnetic mode which is formed by the dynamic interaction between a magnetic quadrupole mode and an electric monopole mode in a two-dimensional electromagnetic Helmholtz cavity. It is termed a magnetic symmetric dipole mode since it shares similarity with a magnetic dipole mode in the sense that their radiation is both overwhelmingly dominant in the forward and backward directions with respect to the incident wave. However, the phase distribution in the two radiation directions is symmetric, in stark contrast to the antisymmetry of magnetic dipole modes. When the Helmholtz cavities are arranged in a line, the incident wave will be reflected back to the source, in other words, retroreflection occurs because of the peculiar properties of magnetic symmetric dipole modes. We show that the retroreflection is quite robust against the disorder of the orientation angle of Helmholtz cavities and there exists a wide tolerance for wavelength and the outer radius of the cavity. With low fabrication demands, this might offer a feasible solution for the design of ultrathin retroreflectors towards device miniaturization and the realization of multiplexing holography.

15.
Opt Express ; 28(5): 7585-7595, 2020 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-32225983

RESUMEN

We present the design of an adiabatic taper coupled Ge1-xSix electro-absorption modulator, which is based on Franz-Keldysh effect. The device has an active region of 0.8×50 µm2, an extinction ratio of more than 6 dB and an insertion loss less than 3 dB at the wavelength of 1550 nm. The operating bandwidth can be broadened to more than 90 nm by an AlN block assisted heater with only 6.2 mW energy consumption. Moreover, the operating wavelength shift caused by material composition deviation can be compensated to the expected wavelength by thermal tuning. This design may play an important role in next-generation, high-density optical integrations for datacom and high-performance computing.

16.
Genet Mol Biol ; 40(2): 525-529, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28644508

RESUMEN

Studies have demonstrated that miRNA-378 is expressed in various malignant tumors. In the present study, we aimed to explore the expression of serum miRNA-378 and its clinical significance in renal cell carcinoma (RCC) patients. A total of 75 RCC patients, 63 renal cysts (RC) patients and 75 healthy controls were selected. The miRNA-378 level in RCC and RC groups was significantly higher than in healthy control group, with RCC group having the highest level. The miRNA-378 levels were significantly decreased within the same group after surgery. When compared with healthy controls, RC group had higher levels but not significantly (p > 0.05) while levels in RCC group were significantly higher (p < 0.05). miRNA-378 expression was correlated with clinical stage and differentiation degree, but not correlated with patient's age, gender, surgical strategy and tumor diameter. The AUC of miRNA-378 was 0.896, 95% confidence interval was 0.847 to 0.945, and AUC hypothesis testing was statistically significant (p < 0.001, RCC vs healthy control). miRNA-378 shows potential in the diagnosis and prediction of postoperative curative effect of renal cell carcinoma, but further studies with lager samples are needed.

17.
Genet. mol. biol ; 40(2): 525-529, Apr.-June 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-892406

RESUMEN

Abstract Studies have demonstrated that miRNA-378 is expressed in various malignant tumors. In the present study, we aimed to explore the expression of serum miRNA-378 and its clinical significance in renal cell carcinoma (RCC) patients. A total of 75 RCC patients, 63 renal cysts (RC) patients and 75 healthy controls were selected. The miRNA-378 level in RCC and RC groups was significantly higher than in healthy control group, with RCC group having the highest level. The miRNA-378 levels were significantly decreased within the same group after surgery. When compared with healthy controls, RC group had higher levels but not significantly (p > 0.05) while levels in RCC group were significantly higher (p < 0.05). miRNA-378 expression was correlated with clinical stage and differentiation degree, but not correlated with patient's age, gender, surgical strategy and tumor diameter. The AUC of miRNA-378 was 0.896, 95% confidence interval was 0.847 to 0.945, and AUC hypothesis testing was statistically significant (p < 0.001, RCC vs healthy control). miRNA-378 shows potential in the diagnosis and prediction of postoperative curative effect of renal cell carcinoma, but further studies with lager samples are needed.

18.
Sci Rep ; 6: 33522, 2016 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-27628099

RESUMEN

Coupling electron beams carrying information into electronic units is fundamental in microelectronics. This requires precision manipulation of electron beams through a coupler with a good focusing ability. In graphene, the focusing of wide electron beams has been successfully demonstrated by a circular p-n junction. However, it is not favorable for information coupling since the focal length is so small that the focal spot locates inside the circular gated region, rather than in the background region. Here, we demonstrate that an array of gate-defined quantum dots, which has gradually changing lattice spacing in the direction transverse to propagation, can focus electrons outside itself, providing a possibility to make a coupler in graphene. The focusing effect can be understood as due to the gradient change of effective refractive indices, which are defined by the local energy band in a periodic potential. The strong focusing can be achieved by suitably choosing the lattice gradient and the layer number in the incident direction, offering an effective solution to precision manipulation of electron beams with wide electron energy range and high angular tolerance.

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