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1.
Small ; 20(25): e2309279, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38214439

RESUMO

Radiation resistance in breast cancer resulting in residual lesions or recurrence is a significant cause to radiotherapy failure. Cancer-associated fibroblasts (CAFs) and radiotherapy-induced senescent CAFs can further lead to radiation resistance and tumor immunosuppressive microenvironment. Here, an engineering cancer-cell-biomimetic nanoplatform is constructed for dual-targeted clearance of CAFs as well as senescent CAFs. The nanoplatform is prepared by 4T1 cell membrane vesicles chimerized with FAP single-chain fragment variable as the biomimetic shell for targeting of CAFs and senescent CAFs, and PLGA nanoparticles (NPs) co-encapsulated with nintedanib and ABT-263 as the core for clearance of CAFs and senescent CAFs, which are noted as FAP-CAR-CM@PLGA-AB NPs. It is evidenced that FAP-CAR-CM@PLGA-AB NPs directly suppressed the tumor-promoting effect of senescent CAFs. It also exhibits prolonged blood circulation and enhanced tumor accumulation, dual-cleared CAFs and senescent CAFs, improved radiation resistance in both acquired and patient-derived radioresistant tumor cells, and effective antitumor effect with the tumor suppression rate of 86.7%. In addition, FAP-CAR-CM@PLGA-AB NPs reverse the tumor immunosuppressive microenvironment and enhance systemic antitumor immunity. The biomimetic system for dual-targeted clearance of CAFs and senescent CAFs provides a potential strategy for enhancing the radio-sensitization of breast cancer.


Assuntos
Neoplasias da Mama , Fibroblastos Associados a Câncer , Senescência Celular , Nanopartículas , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/tratamento farmacológico , Feminino , Nanopartículas/química , Humanos , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Senescência Celular/efeitos dos fármacos , Tolerância a Radiação/efeitos dos fármacos , Camundongos , Biomimética/métodos , Microambiente Tumoral/efeitos dos fármacos , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química
2.
Mol Pharm ; 21(6): 2659-2672, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38695194

RESUMO

Regulatory T cells (Tregs), a subset of CD4+ T cells, are indispensable in maintaining immune self-tolerance and have been utilized in various diseases. Treg-derived extracellular vesicles (Treg-EVs) have been discovered to play an important role in the mechanism of Treg functions. As cell-derived membranous particles, EVs carry multiple bioactive substances that possess tremendous potential for theranostics. Treg-EVs are involved in numerous physiological and pathological processes, carrying proteins and miRNAs inherited from the parental cells. To comprehensively understand the function of Treg-EVs, here we reviewed the classification of Treg-EVs, the active molecules in Treg-EVs, their various applications in diseases, and the existing challenges for Treg-EVs based theranostics. This Review aims to clarify the feasibility and potential of Treg-EVs in diseases and theranostics, facilitating further research and application of Treg-EVs.


Assuntos
Vesículas Extracelulares , Linfócitos T Reguladores , Linfócitos T Reguladores/imunologia , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/imunologia , Humanos , Animais , Nanomedicina Teranóstica/métodos , MicroRNAs/genética , Medicina de Precisão/métodos
3.
J Infect Chemother ; 30(6): 544-547, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37992864

RESUMO

Streptococcus suis is a pathogen of emerging zoonotic diseases and meningoencephalitis is the most frequent clinical symptom of S. suis infection in humans. Rapid diagnosis of S. suis meningoencephalitis is critical for the treatment of the disease. While the current routine microbiological tests including bacterial culture and gram staining are poorly sensitive, diagnosis of S. suis meningoencephalitis by metagenomic next-generation sequencing (mNGS) has been rarely reported. Here, we report a 52-year-old female pork food producer with a broken finger developed S. suis meningoencephalitis. After her admission, no pathogenic bacteria were detected through bacterial culture and Gram staining microscopy in the cerebrospinal fluid obtained via lumbar puncture. However, mNGS identified the presence of S. suis in the sample. mNGS is a promising diagnostic tool for rapid diagnosis of rare infectious diseases in the central nervous system.

4.
J Environ Manage ; 351: 119884, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38142598

RESUMO

Rivers have been widely reported as important CO2 emitters to the atmosphere. Rapid urbanization has a profound impact on the carbon biogeochemical cycle of rivers, leading to enhanced riverine CO2 evasions. However, it is still unclear whether the spatial-temporal patterns of CO2 emissions in the rivers draining diverse landscapes dominated by urbanization were stable, especially in mountainous areas. This study carried out a two-year investigation of water environmental hydrochemistry in three small mountainous rivers draining urban, suburban and rural landscapes in southwestern China, and CO2 partial pressure (pCO2) and fluxes (fCO2) in surface water were measured using headspace equilibrium method and classical thin boundary layer model. The average pCO2 and fCO2 in the highly urbanized river were of 4783.6 µatm and 700.0 mmol m-2 d-1, conspicuously higher than those in the rural river (1525.9 µatm and 123.2 mmol m-2 d-1), and the suburban river presented a moderate level (3114.2 µatm and 261.2 mmol m-2 d-1). It provided even clearer evidence that watershed urbanization could remarkably enhance riverine CO2 emissions. More importantly, the three rivers presented different longitudinal variations in pCO2, implying diversified spatial patterns of riverine CO2 emissions as a result of urbanization. The urban land can explain 49.6-69.1% of the total spatial variation in pCO2 at the reach scale, indicating that urban land distribution indirectly dominated the longitudinal pattern of riverine pCO2 and fCO2. pCO2 and fCO2 in the three rivers showed similar temporal variability with higher warm-rainy seasons and lower dry seasons, which are significantly controlled by weather dynamics, including monthly temperature and precipitation, but seem to be impervious to watershed urbanization. High temperature-stimulated microorganisms metabolism and riched-CO2 runoff input lead much higher pCO2 in warm-rainy seasons. However, it showed more sensitivity of pCO2 to monthly weather dynamics in urbanized rivers than that in rural rivers, and warm-rainy seasons showed hot moments of CO2 evasion for urban rivers. TOC, DOC, TN, pH and DO were the main controls on pCO2 in the urban and suburban rivers, while only pH and DO were connected with pCO2 in the rural rivers. This indicated differential controls and regulatory processes of pCO2 in the rivers draining diverse landscapes. Furthermore, it suggested that pCO2 calculated by the pH-total alkalinity method would obviously overestimate pCO2 in urban polluted rivers due to the inevitable influence of non-carbonate alkalinity, and thus, a relatively conservative headspace method should be recommended. We highlighted that urbanization and weather dynamics co-dominated the multiformity and uncertainty in spatial-temporal patterns of riverine CO2 evasions, which should be considered when modeling CO2 dynamics in urbanized rivers.


Assuntos
Rios , Urbanização , Rios/química , Dióxido de Carbono/análise , Água , Chuva , China , Monitoramento Ambiental
5.
Eur Radiol ; 33(5): 3029-3040, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36576550

RESUMO

OBJECTIVES: To investigate the predictive value of CT-derived fractional flow reserve (FFRCT) in anastomosis occlusion after coronary artery bypass graft (CABG) surgery. METHODS: Patients undergoing CABG with both pre- and post-operative coronary computed tomographic angiography (CCTA) were retrospectively included. Preoperative CCTA studies were used to evaluate anatomical and FFRCT information of target vessels. A diameter stenosis (DS) ≥ 70% or left main > 50% was considered to be anatomically severe, while FFRCT value ≤ 0.80 be functionally significant. The primary endpoint was anastomosis occlusion evaluated on post-operative CCTA during follow-up. Predictors of anastomosis occlusion were assessed by the multivariate binary logistic regression with generalized estimating equations. RESULTS: A total of 270 anastomoses were identified in 88 enrolled patients. Forty-one anastomoses from 30 patients exhibited occlusion during a follow-up of 15.3 months after CABG. The occluded group had significantly increased prevalence of non-severe DS (58.5% vs. 40.2%; p = 0.023) and non-significant FFRCT (48.8% vs. 10.0%; p < 0.001). Multivariable analysis indicated FFRCT ≤ 0.80 (odds ratio [OR]: 0.10, 95% CI: 0.03-0.33; p < 0.001) and older age (OR: 0.92, 95% CI: 0.87-0.97; p = 0.001) were predictors for bypass patency during follow-up, while myocardial infarction history and anastomosis to a local lesion or bifurcation (all p value < 0.05) were predictors of occlusion. Adding FFRCT into the model based on the clinical and anatomical predictors had an improved AUC of 0.848 (p = 0.005). CONCLUSIONS: FFRCT ≤ 0.80 was associated with a significant risk reduction of anastomosis occlusion after CABG. Preoperative judgment of the hemodynamic significance may improve the CABG surgery strategy and reduce graft failure. KEY POINTS: • FFRCT ≤ 0.80 was associated with a significant risk reduction of anastomosis occlusion after CABG. • The addition of FFRCT into the integrated model including clinical (age and history of myocardial infarction) and anatomical CCTA indicators (local lesion and bifurcation) significantly improved the model performance with an AUC of 0.848 (p = 0.005). • Preoperative judgment of the hemodynamic significance may help improve the decision-making and surgery planning in patients indicated for CABG and significantly reduce graft failure, without an extra radiation exposure and risk of invasive procedure.


Assuntos
Doença da Artéria Coronariana , Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Infarto do Miocárdio , Doenças Vasculares , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , Estudos Retrospectivos , Angiografia Coronária/métodos , Prognóstico , Valor Preditivo dos Testes , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/cirurgia , Tomografia Computadorizada por Raios X , Ponte de Artéria Coronária , Angiografia por Tomografia Computadorizada/métodos
6.
Phys Chem Chem Phys ; 25(11): 7927-7936, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36861757

RESUMO

Recent progress in organic electronics has attracted interest due to their excellent characteristics that include photovoltaic, light emission, and semiconducting behaviours. Spin-induced properties play important roles in organic electronics, while introducing spin into an organic layer in which spin responses, such as a weak spin-orbital coupling and long spin-relaxation time, allows a variety of spintronic applications to be achieved. However, such spin responses are rapidly attenuated by misalignment in the electronic structure of hybrid structures. We report herein on the energy level diagrams of Ni/rubrene bilayers that can be tuned by an alternating stacking. The band edges of the highest occupied molecular orbital (HOMO) levels were determined to be 1.24 and 0.48 eV relative to the Fermi level for Ni/rubrene/Si and rubrene/Ni/Si bilayers, respectively. This raises a possibility of accumulating electric dipoles at the ferromagnetic/organic semiconductor (FM/OSC) interface, which would inhibit the transfer of spin in the OSC layer. This phenomenon is caused by the formation of a Schottky-like barrier in the rubrene/Ni heterostructures. According to the information about the band edges of the HOMO levels, schematic plots of the HOMO shift in the electronic structure of the bilayers are presented. Based on the lower value of the effective uniaxial anisotropy for Ni/rubrene/Si, the uniaxial anisotropy was suppressed compared to that of rubrene/Ni/Si. The characteristics of the formation of Schottky barriers at the FM/OSC interface have an impact on the temperature-dependent spin states in the bilayers.

7.
Phys Chem Chem Phys ; 25(46): 32029-32039, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37982149

RESUMO

Interfaces of ferromagnetic/organic material hybrid structures refer to the spin interface that governs physical properties for achieving high spin polarization, low impedance mismatch, and long spin relaxation. Spintronics can add new functionalities to electronic devices by taking advantage of the spin degree of freedom of electrons, which makes understanding the dynamic magnetic properties of magnetic films important for spintronic device applications. Our knowledge regarding the magnetic dynamics and magnetic anisotropy of combining ferromagnetic layer and organic semiconductor by microwave-dependent magnetic measurements remains limited. Herein, we report the impact of an organic layer on the dynamic magnetic behavior of nickel/rubrene bilayers deposited on a Si(100) substrate. From magnetic dynamic measurements, opposite signs of effective magnetic fields between the in-plane (IP) and out-of-plane (OP) configurations suggest that the magnetization of Ni(x)/rubrene/Si prefers to coexist. A shift in OP resonance fields to higher values can mainly be attributed to the enhanced second-order anisotropy parameter K2 value. Based on IP measurements, a two-magnon scattering mechanism is dominant for thin Ni(x)/rubrene/Si bilayers. By adding a rubrene layer, the highly stable IP combined with the tunable OP ferromagnetic resonance spectra for Ni(x)/rubrene/Si bilayers make them promising materials for use in microwave magnetic devices and spintronics with controllable perpendicular magnetic anisotropy.

8.
J Nanobiotechnology ; 21(1): 347, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37752555

RESUMO

Cancer therapeutic vaccine can induce antigen-specific immune response, which has shown great potential in cancer immunotherapy. As the key factor of vaccine, antigen plays a central role in eliciting antitumor immunity. However, the insufficient antigen delivery and low efficiency of antigen presentation by dendritic cells (DCs) have greatly restricted the therapeutic efficiency of vaccine. Here we developed a kind of DC hybrid zinc phosphate nanoparticles to co-deliver antigenic peptide and photosensitive melanin. Owing to the chelating ability of Zn2+, the nanoparticles can co-encapsulate antigenic peptide and melanin with high efficiency. The nanovaccine showed good physiological stability with the hydration particle size was approximately 30 nm, and zeta potential was around - 10 mV. The nanovaccine showed homologous targeting effect to DCs in vivo and in vitro, efficiently delivering antigen to DCs. Meanwhile, the nanovaccine could effectively reflux to the tumor-draining lymph nodes. When combined with near-infrared irradiation, the nanovaccine induced effective mild heat in vitro and in vivo to promote antigen presentation. After administrating to MC38 tumor-bearing mice, the hybrid nanovaccine effectively promoted the maturation of DCs, the expansion of cytotoxic T lymphocytes and helper T cells, and the secretion of immunostimulatory cytokines, thereby significantly inhibiting tumor growth.


Assuntos
Vacinas Anticâncer , Neoplasias , Animais , Camundongos , Temperatura Alta , Melaninas , Imunoterapia , Imunização , Células Dendríticas , Neoplasias/terapia
9.
Rev Esp Enferm Dig ; 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37732344

RESUMO

A 42-year-old male patient experienced hemorrhagic shock after endotracheal intubation. Emergency gastroscopy showed no upper gastrointestinal bleeding, but active tracheal bleeding. After sedation, the tracheal bleeding was successfully stopped with gastroscopy. Post-intubation airway bleeding is a rare but fatal adverse event, and finding the exact bleeding site and quickly stopping the bleeding is the key to successful treatment.

10.
Plant Dis ; 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36222727

RESUMO

Stephania tetrandra S. Moore is a perennial liana and is widely cultivated in southern China for traditional Chinese medicine as a diuretic, anti-inflammatory, and antirheumatic treatment (Jiang et al. 2020). In August 2021, it was observed that a severe stem rot disease affected St. tetrandra cultivated in Anfu, Jiangxi province, China (114°27'26" E, 27°22'46" N). The disease symptoms included constriction and rot at the base of the stem, and covered with a layer of white mycelia. The plants above-ground finally wilted and dried with a disease incidence ranging from 8% to 16%. Lots of dried plants formed withered patches of field. Sections (1.0~2.0 cm) from browning stem tissues were surface-disinfected with 75% ethanol for 15 s, followed by 60 s in 4% NaClO, rinsed twice in sterile water, dried on sterilized filter paper, placed on potato dextrose agar (PDA), and incubated at 26°C in the dark for 3 days. A white rhizomorphic fungal mycelium, that is similar to the mycelium of strain FJSR0 on the surface of an infected plant in the field, was isolated from the cultured tissues with 67% frequency. When incubated on PDA, white and fluffy mycelia with even margins and a slight halo formed. Mycelia-produced clamp connections were observed. Colonies grew quickly and covered the dish (diameter: 9 cm) in 5 or 6 days. After that, sclerotia were initially white, then turned yellow, and chestnut brown at maturity. Spherical and subspherical sclerotia were observed after 8 days, with each plate containing 448 to 634 sclerotia (0.8 to 1.4 mm diameter; mean = 0.94 mm; n = 50). On the basis of morphology, the pathogen was similar to Sclerotium rolfsii Sacc. [teleomorph: Athelia rolfsii (Curzi) Tu & Kimbrough] (Sun et al. 2020; Ling et al. 2021). For molecular confirmation, the internal transcribed spacer (ITS) region with approximately 680 bp was amplified from strains FJRS0 and FJRS1 using primers ITS1/ITS4 (White et al. 1990). Two distinct types (different in one SNP and one 1-bp InDel) of ITS sequences were obtained from each isolate, and all isolates contain the two types (FJSR0: ON972516, ON972517; FJSR1: ON972520, ON972518). BLAST analysis of each type found that the hits, with identities >99%, are A. rolfsii except for two Sc. delphinii sequences (GU567775.1 and MK073010.1). Phylogenetic analysis placed strains FJSR0 and FJSR1 in the same clade as Sc. rolfsii but away from Sc. delphinii based on the previous method (Sun et al. 2021). Both morphological and molecular characteristics confirmed that the strains were Sc. rolfsii. For pathogenicity tests, PDA plugs (8 mm in diameter) covered with 5-day-old fungal mycelium were inoculated at the stem bases of three healthy St. tetrandra seedings and incubated at 26℃ and relative humidity of 80%. On the fifth day, inoculated plants were wilting. The infected stem bases turned brown to black and constricted as previously observed in the field. Some leaves, infected by the mycelium expanded from the PDA plugs, developed an orange and irregular spot. Sclerotia were observed 20 days post inoculation. In contrast, the leaves and stems of non-inoculated control plants remained symptomless. Pathogenicity tests were repeated three times. The fungus was reisolated consistently from each symptomatic tissue, thus completing Koch's postulates. Although Sc. rolfsii has been previously reported to cause a southern blight symptoms on vegetables, ornamentals, grass, and medicinal and leguminous crops (Sun et al. 2020; Ling et al. 2021), this is the first report of Sc. rolfsii causing similar symptoms of southern blight on St. tetrandra in China.

11.
Mikrochim Acta ; 189(10): 374, 2022 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-36068328

RESUMO

A chemiresistive biosensor is described for simple and selective detection of miRNA-21. We developed chemical vapor deposition (CVD) and low-damage plasma treatment (LDPT)-treated bilayer graphene composite of graphene oxide/graphene (GO/GR) for the determination of a reliable biomarker. We have successfully overcome the self-limiting growth mechanism by using CVD method to grow more than one layer of graphene on copper foil. In addition, LDPT can be used to form GO/GR structures for chemiresistive biosensor applications. Due to the direct formation of BLGR (bilayer graphene), the coupling between graphene layers is theoretically superior to that of stacked BLGR, which is also confirmed by the blue shift of the characteristic peak of graphene in Raman spectroscopy. The shift is about double compared with that of stacked BLGR. Based on the results, the limit of detection for the target miRNA-21 was calculated to be 5.20 fM and detection rage is calculated as 100 fM to 10 nM, which is obviously better performance. Compared with previous work, this chemiresistive biosensor has good selectivity, and stability towards detection of miRNA-21. The ability to detect miRNA-21 in different biological fluids was almost identical to that in pH 7.4 phosphate-buffered saline (PBS). Thus, the proposed bilayer GO/GR of modified chemiresistive biosensor may potentially be applied to detect cancer cells in clinical examinations.


Assuntos
Técnicas Biossensoriais , Grafite , MicroRNAs , Neoplasias , Biomarcadores Tumorais , Técnicas Biossensoriais/métodos , Gases/química , Grafite/química , Neoplasias/diagnóstico
12.
Int Orthop ; 46(3): 661-668, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34647137

RESUMO

PURPOSE: To summarize the evolution of Ilizarov technology in China, highlight important milestones, introduce the atmosphere of the era concerning the first uses and development of this technology, and share Chinese modification and experience in this field. METHOD: A thorough interview with senior ASAMI members of China and literature search and physical books in libraries was undertaken to summarize the history of Ilizarov technology in China. RESULTS: The formal development of Ilizarov technology began when professor Ilizarov himself came to Beijing (1991) and gave a speech. In the following 31 years, his technology was rapidly developed through China, with many symposiums held and associations established including ASAMI China (2003) and ILLRS China (2015). Today, Ilizarov technology has become the main treatment of complex fractures, defects, nonunion, infections, deformities, and chronic ischemic ulcers of the limbs. In those years, Chinese scholars also developed some special treatment methods and made many modifications to Ilizarov external fixators. CONCLUSION: Ilizarov technology has developed in China for 31 years. It revolutionized the treatment of complex limb traumas, deformities, and diseases. In the treatment of millions of patients, Chinese scholars had many unique experiences and made modifications to this technology which is worthy to share with the world.


Assuntos
Técnica de Ilizarov , Fraturas da Tíbia , Fixadores Externos , Extremidades , Humanos , Tecnologia , Fraturas da Tíbia/cirurgia , Resultado do Tratamento
13.
Angew Chem Int Ed Engl ; 61(19): e202116635, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35274415

RESUMO

The severe performance degradation of high-capacity Li-O2 batteries induced by Li dendrite growth and concentration polarization from the low Li+ transfer number of conventional electrolytes hinder their practical applications. Herein, lithiated Nafion (LN) with the sulfonic group immobilized on the perfluorinated backbone has been designed as a soluble lithium salt for preparing a less flammable polyelectrolyte solution, which not only simultaneously achieves a high Li+ transfer number (0.84) and conductivity (2.5 mS cm-1 ), but also the perfluorinated anion of LN produces a LiF-rich SEI for protecting the Li anode from dendrite growth. Thus, the Li-O2 battery with a LN-based electrolyte achieves an all-round performance improvement, like low charge overpotential (0.18 V), large discharge capacity (9508 mAh g-1 ), and excellent cycling performance (225 cycles). Besides, the fabricated pouch-type Li-air cells exhibit promising applications to power electronic equipment with satisfactory safety.

14.
Heart Surg Forum ; 24(2): E317-E319, 2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33798044

RESUMO

Epistaxis is a common emergency, and its main causes are hypertensive crisis and trauma. Nasal packing is the primary treatment. After active symptomatic treatment, the symptoms of epistaxis effectively can be controlled. In this case report, the patient was treated with epistaxis many times in the outpatient department. After nasal examination, there was a clear bleeding point, and it was treated with gauze packing or silver nitrate cauterization. The symptoms of epistaxis gradually got worse and was accompanied with fever and progressive anemia. After blood culture and color Doppler ultrasound examination, it was confirmed that it was endocarditis caused by defective hypoxic bacterial infection. After active antibacterial and surgical treatment, the symptoms of epistaxis, fever and anemia were relieved.


Assuntos
Endocardite/complicações , Epistaxe/complicações , Antibacterianos/uso terapêutico , Ascomicetos , Ecocardiografia Doppler em Cores , Endocardite/diagnóstico , Endocardite/tratamento farmacológico , Epistaxe/diagnóstico , Humanos , Masculino , Adulto Jovem
15.
J Nat Prod ; 83(11): 3372-3380, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33180497

RESUMO

The effects of l-tryptophan supplementation on secondary metabolite production in the marine-derived fungus Fusarium sp. L1 were investigated by culturing the fungus in GPY medium with and without the amino acid. HPLC analysis of the products showed distinct metabolite profiles between the two cultures. The 1H NMR spectrum of the EtOAc extract of the culture supplemented with l-tryptophan displayed a series of characteristic aromatic proton signals (δH 6.50-8.50) and NH signals (δH 10.50-11.50) that were not observed in those from cultures not supplemented with l-tryptophan. Subsequently, 23 distinct indole alkaloids, including six new compounds, fusaindoterpenes A and B (1 and 2), fusariumindoles A-C (3-5), and (±)-isoalternatine A (6), together with 17 known compounds, were obtained from this culture. Fusaindoterpene A (1) contains a 6/9/6/6/5 heterocyclic system. Their chemical structures were determined by analysis of HRMS, NMR spectroscopy, optical rotation calculation, ECD calculation, and single-crystal X-ray diffraction data. Compounds 2, 9, and 15 displayed inhibitory activity against the Zika virus (ZIKV) in a standard plaque assay with EC50 values of 7.5, 4.2, and 5.0 µM, respectively, while not showing significant cell cytotoxicity against the A549 adenocarcinomic human alveolar basal epithelial cell line.


Assuntos
Antivirais/farmacologia , Fusarium/efeitos dos fármacos , Alcaloides Indólicos/farmacologia , Água do Mar/microbiologia , Triptofano/farmacologia , Zika virus/efeitos dos fármacos , Antivirais/química , Linhagem Celular Tumoral , Cristalografia por Raios X , Fusarium/metabolismo , Humanos , Alcaloides Indólicos/química , Análise Espectral/métodos
16.
Mar Drugs ; 18(10)2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32992455

RESUMO

Ascomylactam A was reported for the first time as a new 13-membered-ring macrocyclic alkaloid in 2019 from the mangrove endophytic fungus Didymella sp. CYSK-4 from the South China Sea. The aim of our study was to delineate the effects of ascomylactam A (AsA) on lung cancer cells and explore the antitumor molecular mechanisms underlying of AsA. In vitro, AsA markedly inhibited the cell proliferation with half-maximal inhibitory concentration (IC50) values from 4 to 8 µM on six lung cancer cell lines, respectively. In vivo, AsA suppressed the tumor growth of A549, NCI-H460 and NCI-H1975 xenografts significantly in mice. Furthermore, by analyses of the soft agar colony formation, 5-ethynyl-20-deoxyuridine (EdU) assay, reactive oxygen species (ROS) imaging, flow cytometry and Western blotting, AsA demonstrated the ability to induce cell cycle arrest in G1 and G1/S phases by increasing ROS generation and decreasing of Akt activity. Conversely, ROS inhibitors and overexpression of Akt could decrease cell growth inhibition and cell cycle arrest induced by AsA. Therefore, we believe that AsA blocks the cell cycle via an ROS-dependent Akt/Cyclin D1/Rb signaling pathway, which consequently leads to the observed antitumor effect both in vitro and in vivo. Our results suggest a novel leading compound for antitumor drug development.


Assuntos
Alcaloides/farmacologia , Antineoplásicos/farmacologia , Ascomicetos/química , Neoplasias Pulmonares/tratamento farmacológico , Alcaloides/administração & dosagem , Alcaloides/isolamento & purificação , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína do Retinoblastoma/metabolismo , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
17.
J Cell Physiol ; 234(2): 1369-1379, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30076725

RESUMO

BACKGROUND: Cigarette smoking is the most well-established risk factor for colorectal cancer (CRC). However, the mechanisms of smoking-associated colorectal carcinogenesis are poorly understood. METHODS: The effects of prediagnosis tobacco use on clinical characteristics, overall survival (OS), and recurrence-free survival (RFS) were analyzed in 396 patients with CRC. Associations between smoking status and OS and RFS were evaluated using Cox's proportional hazards regression. Furthermore, the effects of nicotine on the CRC cell lines SW620 and HT-29 were evaluated using in vitro assays. RESULTS: "Ever smoking" was associated with elevated serum carcinoembryonic antigen, American Joint Committee on Cancer T category, metastasis, and poorer OS and RFS in patients with CRC (OS: hazard ratio [HR] = 1.74, 95% confidence interval [CI], 1.07-2.81, p = 0.025; RFS: HR = 1.66, 95% CI: 1.18-2.34, p = 0.004). MicroRNA (miR)-200c was downregulated in CRC and tumor-adjacent tissues from ever smokers compared with the corresponding tissues from never smokers with CRC. Nicotine inhibited miR-200c expression in a dose- and time-dependent manner in SW620 and HT-29 CRC cell lines. Nicotine induced cell proliferation, migration, and invasion and promoted the epithelial-mesenchymal transition in SW620 and HT-29 cells, and these effects were attenuated by overexpression of miR-200c. CONCLUSION: Our findings support the adverse effects of prediagnosis cigarette smoking on prognosis and clinical behavior in CRC. We demonstrate a novel oncogenic mechanism by which nicotine promotes growth and metastasis in CRC by downregulating miR-200c.


Assuntos
Movimento Celular/efeitos dos fármacos , Fumar Cigarros/efeitos adversos , Neoplasias Colorretais/etiologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , MicroRNAs/metabolismo , Nicotina/toxicidade , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Relação Dose-Resposta a Droga , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Células HT29 , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Invasividade Neoplásica , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Transdução de Sinais , Fatores de Tempo
18.
Mol Cancer ; 18(1): 110, 2019 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-31228940

RESUMO

BACKGROUND: METTL3 is known to be involved in all stages in the life cycle of RNA. It affects the tumor formation by the regulation the m6A modification in the mRNAs of critical oncogenes or tumor suppressors. In bladder cancer, METTL3 could promote the bladder cancer progression via AFF4/NF-κB/MYC signaling network by an m6A dependent manner. Recently, METTL3 was also found to affect the m6A modification in non-coding RNAs including miRNAs, lincRNAs and circRNAs. However, whether this mechanism is related to the proliferation of tumors induced by METTL3 is not reported yet. METHODS: Quantitative real-time PCR, western blot and immunohistochemistry were used to detect the expression of METTL3 in bladder cancer. The survival analysis was adopted to explore the association between METTL3 expression and the prognosis of bladder cancer. Bladder cancer cells were stably transfected with lentivirus and cell proliferation and cell cycle, as well as tumorigenesis in nude mice were performed to assess the effect of METTL3 in bladder cancer. RNA immunoprecipitation (RIP), co-immunoprecipitations and RNA m6A dot blot assays were conducted to confirm that METTL3 interacted with the microprocessor protein DGCR8 and modulated the pri-miR221/222 process in an m6A-dependent manner. Luciferase reporter assay was employed to identify the direct binding sites of miR221/222 with PTEN. Colony formation assay and CCK8 assays were conducted to confirm the function of miR-221/222 in METTL3-induced cell growth in bladder cancer. RESULTS: We confirmed the oncogenic role of METTL3 in bladder cancer by accelerating the maturation of pri-miR221/222, resulting in the reduction of PTEN, which ultimately leads to the proliferation of bladder cancer. Moreover, we found that METTL3 was significantly increased in bladder cancer and correlated with poor prognosis of bladder cancer patients. CONCLUSIONS: Our findings suggested that METTL3 may have an oncogenic role in bladder cancer through interacting with the microprocessor protein DGCR8 and positively modulating the pri-miR221/222 process in an m6A-dependent manner. To our knowledge, this is the first comprehensive study that METTL3 affected the tumor formation by the regulation the m6A modification in non-coding RNAs, which might provide fresh insights into bladder cancer therapy.


Assuntos
Adenosina/análogos & derivados , Metiltransferases/metabolismo , MicroRNAs/genética , Neoplasias da Bexiga Urinária/patologia , Adenosina/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Metiltransferases/genética , Camundongos , Transplante de Neoplasias , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Proteínas de Ligação a RNA/metabolismo , Análise Serial de Tecidos , Regulação para Cima , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo
19.
Plant Biotechnol J ; 17(1): 289-301, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29905035

RESUMO

The fruit epidermal features such as the size of tubercules are important fruit quality traits for cucumber production. But the mechanisms underlying tubercule formation remain elusive. Here, tubercule size locus CsTS1 was identified by map-based cloning and was found to encode an oleosin protein. Allelic variation was identified in the promoter region of CsTS1, resulting in low expression of CsTS1 in all 22 different small-warty or nonwarty cucumber lines. High CsTS1 expression levels were closely correlated with increased fruit tubercule size among 44 different cucumber lines. Transgenic complementation and RNAi-mediated gene silencing of CsTS1 in transgenic cucumber plants demonstrated that CsTS1 positively regulates the development of tubercules. CsTS1 is highly expressed in the peel at fruit tubercule forming and enlargement stage. Auxin content and expression of three auxin signalling pathway genes were altered in the 35S:CsTS1 and CsTS1-RNAi fruit tubercules, a result that was supported by comparing the cell size of the control and transgenic fruit tubercules. CsTu, a C2 H2 zinc finger domain transcription factor that regulates tubercule initiation, binds directly to the CsTS1 promoter and promotes its expression. Taken together, our results reveal a novel mechanism in which the CsTu-TS1 complex promotes fruit tubercule formation in cucumber.


Assuntos
Cucumis sativus/crescimento & desenvolvimento , Frutas/crescimento & desenvolvimento , Genes de Plantas/genética , Clonagem Molecular , Cucumis sativus/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas/fisiologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Regiões Promotoras Genéticas/genética
20.
Phys Chem Chem Phys ; 21(27): 14583-14588, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31241647

RESUMO

Electrochemical nitrogen (N2) fixation as an effective method has realized the sustainable production of ammonia where efficient electrocatalysts for converting N2 into NH3 at room temperature have become a key scientific issue. Herein, we proposed that the catalytic activity of a single Mo atom supported on graphene (Mo/G) for the nitrogen reduction reaction (NRR) can be tuned by non-metal heteroatom (B, N, P, S, Se etc.) doping. Our density functional theory (DFT) calculations revealed that the Se atom is the best doping element to tune the optimal electronic structure of the Mo atom for catalyzing the NRR among these heteroatoms, leading to the lowest potential of 0.41 V vs. RHE for Mo/SeG, which is much better than the current metal-based catalysts. Our work provided a new strategy to design electrocatalysts for the NRR.

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