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1.
Front Pharmacol ; 12: 731741, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34925002

RESUMEN

Triple-negative breast cancers are heterogeneous, poorly prognostic, and metastatic malignancies that result in a high risk of death for patients. Targeted therapy for triple-negative breast cancer has been extremely challenging due to the lack of expression of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2. Clinical treatment regimens for triple-negative breast cancer are often based on paclitaxel and platinum drugs, but drug resistance and side effects from the drugs frequently lead to treatment failure, thus requiring the development of new therapeutic platforms. In recent years, research on traditional Chinese medicine in modulating the immune function of the body has shown that it has the potential to be an effective treatment option against triple-negative breast cancer. Active components of herbal medicines such as alkaloids, flavonoids, polyphenols, saponins, and polysaccharides have been shown to inhibit cancer cell proliferation and metastasis by activating inflammatory immune responses and can modulate tumor-related signaling pathways to further inhibit the invasion of triple-negative breast cancer. This paper reviews the immunomodulatory mechanisms of different herbal active ingredients against triple-negative breast cancer and provides an outlook on the challenges and directions of development for the treatment of triple-negative breast cancer with herbal active ingredients.

2.
Chem Biol Drug Des ; 98(3): 395-404, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33963664

RESUMEN

"Candidatus Liberibacter asiaticus" (Ca. L. asiaticus) is the causal agent of Huanglongbing disease of citrus and current study focuses on the discovery of novel small-molecule inhibitors against SecA protein of Ca. L. asiaticus. In this study, homologous modeling was used to construct the three-dimensional structure of SecA. Then, molecular docking-based virtual screening and two rounds of in vitro bacteriostatic experiments were utilized to identify novel small-molecule inhibitors of SecA. Encouragingly, 93 compounds were obtained and two of them (P684-2850, P684-3808) showed strong antimicrobial activities against Liberibacter crescens BT-1 in bacteriostatic experiments. Finally, molecular dynamics simulations were employed to explore the binding modes of the receptor-ligand complexes. Results in MD simulations showed that compound P684-3808 was relatively stable during simulation, while compound P684-2850 left the binding pocket. Compound P684-3808 might be suitable as a lead compound for further development of antimicrobial compounds against SecA of Ca. L. asiaticus.


Asunto(s)
Proteínas Bacterianas/antagonistas & inhibidores , Liberibacter/metabolismo , Proteína SecA/antagonistas & inhibidores , Bibliotecas de Moléculas Pequeñas/química , Proteínas Bacterianas/metabolismo , Sitios de Unión , Evaluación Preclínica de Medicamentos , Concentración 50 Inhibidora , Liberibacter/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Proteína SecA/metabolismo , Bibliotecas de Moléculas Pequeñas/metabolismo , Bibliotecas de Moléculas Pequeñas/farmacología
3.
Food Chem ; 353: 129428, 2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-33714119

RESUMEN

Roasting process impacts the chemical profile and aroma of roasted tea. To compare the impacts of far-infrared irradiation and drum roasting treatments (light, medium and heavy degrees), the corresponding roasted teas were prepared from steamed green tea for chemical analyses and quantitative descriptive analysis on aroma, and correlations between volatiles and aroma attributes were studied. There were 8 catechins, 13 flavonol glycosides and 105 volatiles quantified. Under heavy roasting treatments, most catechins and flavonol glycosides decreased, and aldehydes, ketones, furans, pyrroles/pyrazines, and miscellaneous greatly increased, while far-infrared irradiated teas had distinct nutty aroma compared with the roasty and burnt odor of drum roasted teas. The weighted correlation network analysis result showed that 56 volatiles were closely correlated with the aroma attributes of roasted teas. This study reveals the differential chemical and sensory changes of roasted teas caused by different roasting processes, and provides a novel way for flavor chemistry study.


Asunto(s)
Té/química , Compuestos Orgánicos Volátiles/análisis , Catequina/análisis , Análisis por Conglomerados , Culinaria/métodos , Flavonoides/análisis , Cromatografía de Gases y Espectrometría de Masas , Humanos , Rayos Infrarrojos , Odorantes/análisis , Análisis de Componente Principal , Té/metabolismo
4.
Bioresour Technol ; 314: 123766, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32645575

RESUMEN

Endophytic bacteria were isolated from Chlorella vulgaris and co-cultured with its host microalgae to determine whether this symbiotic system is suitable for purifying biogas and biogas slurry. Results showed that endophytic bacteria S395-1 and S395-2 belonged to different genera. Both strains promoted microalgae growth while improving photosynthetic performance, carbonic anhydrase activity, nutrient removal efficiency, and CO2 fixation. The optimal bacteria (S395-2)-to-microalgae ratio and co-culture duration were 10:1 and 7 days. Under this condition, the growth rate and carbonic anhydrase activity were 0.196 ± 0.06 d-1 and 31.24 ± 0.28 EU/cell, respectively. The symbiotic system had removal efficiencies of 88.29 ± 5.03%, 88.31 ± 4.29%, 88.21 ± 4.51%, and 68.13 ± 1.69% for chemical oxygen demand, nitrogen, phosphorus, and CO2, respectively. These results will provide a framework for constructing a microalgal-bacterial consortium that can improve wastewater treatment and enhance biogas quality.


Asunto(s)
Chlorella vulgaris , Microalgas , Biocombustibles , Biomasa , Técnicas de Cocultivo , Nitrógeno , Nutrientes , Fósforo , Aguas Residuales
5.
Bioresour Technol ; 312: 123563, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32460008

RESUMEN

Freshwater microalgae Chlorella vulgaris was cultured and induced with strigolactone (GR24) to simultaneously eliminate nutrients in biogas slurry and purify biogas. Treatment with 10-7 M GR24 yielded maximum growth rate and mean daily productivity for algae at 0.187 ± 0.06 d-1 and 0.097 ± 0.008 g L-1 d-1, respectively. Results from chlorophyll fluorescence transients method demonstrated that moderate concentration of GR24 could enhance the photosynthetic performance of microalgae. In addition, GR24 affected intracellular carbonic anhydrase activity and chlorophyll-a content. Maximum chemical oxygen demand, total nitrogen, and CO2 removal efficiencies were 78.62 ± 2.36%, 76.47 ± 1.53% and 64.05 ± 1.15% with 10-7 M GR24 induction, respectively. Further, highest total phosphorus removal efficiency (80.27 ± 1.93%) was observed at 10-9 M. The optimal GR24 concentration range was determined to be between 10-9 and 10-7 M in consideration with nutrient and CO2 removal efficiencies.


Asunto(s)
Chlorella vulgaris , Microalgas , Biocombustibles , Biomasa , Nitrógeno , Nutrientes , Fósforo , Aguas Residuales
6.
BMC Vet Res ; 15(1): 113, 2019 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-30975135

RESUMEN

BACKGROUND: In May 2017, 17 dogs in a German Shepherd breeding kennel in northern China developed respiratory clinical signs. The owner treated the dogs with an intravenous injection of Shuang-Huang-lian, a traditional Chinese medicine, and azithromycin. The respiratory signs improved 3 days post-treatment, however, cysts were observed in the necks of eight dogs, and three of them died in the following 2 days. CASE PRESENTATION: Quantitative real-time PCR was used to detect canine influenza virus (CIV). All of the dogs in this kennel were positive and the remaining 14 dogs had seroconverted. Two of the dogs were taken to the China Agricultural University Veterinary Teaching Hospital for further examination. Two strains of influenza virus (A/canine/Beijing/0512-133/2017 and A/canine/Beijing/0512-137/2017) isolated from the nasal swabs of these dogs were sequenced and identified as avian-origin H3N2 CIV. For the two dogs admitted to the hospital, hematology showed mild inflammation and radiograph results indicated pneumonia. Cyst fluid was plated for bacterial culture and bacterial 16 s rRNA gene PCR was performed, followed by Sanger sequencing. The results indicated an Enterococcus faecalis infection. Antimicrobial susceptibility tests were performed and dogs were treated with enrofloxacin. All 14 remaining dogs recovered within 16 days. CONCLUSIONS: Coinfection of H3N2 CIV and Enterococcus faecalis was detected in dogs, which has not been reported previously. Our results highlight that CIV infection might promote the secondary infection of opportunistic bacteria and cause more severe and complicated clinical outcomes.


Asunto(s)
Coinfección/veterinaria , Enfermedades de los Perros/virología , Infecciones por Bacterias Grampositivas/veterinaria , Subtipo H3N2 del Virus de la Influenza A , Infecciones por Orthomyxoviridae/veterinaria , Animales , China/epidemiología , Coinfección/epidemiología , Coinfección/microbiología , Coinfección/virología , Brotes de Enfermedades/veterinaria , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/microbiología , Perros/virología , Enterococcus faecalis , Femenino , Infecciones por Bacterias Grampositivas/complicaciones , Infecciones por Bacterias Grampositivas/microbiología , Subtipo H3N2 del Virus de la Influenza A/genética , Masculino , Infecciones por Orthomyxoviridae/complicaciones , Infecciones por Orthomyxoviridae/virología , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria
7.
Water Res ; 145: 721-730, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-30216866

RESUMEN

Phosphorus (P) recovery from waste streams is attracting more attention due to the twin problems of aquatic eutrophication and global phosphorus scarcity. Layered double hydroxide mineral materials are promising phosphate adsorbents due to their excellent anion-exchange abilities and large surface area. In this study, the adsorption isotherms estimated the saturation capacity of calcined layered double hydroxide (LDH) nano-composites for phosphate as 100.7 mg-P/g-adsorbent. Ion exchange is proposed as the major mechanism in the sorption process. The commonly utilized desorption method via sodium hydroxide was found to cause recrystallization of LDH particles in increased crystal size based on the dissolution-reprecipitation (D-R) mechanism. Ammonia solution was used to desorb P from LDH adsorbent. However, struvite crystallization occurred during the desorption process because struvite has a higher precipitation tendency than LDH with sufficient NH4+ ions. The comparison of P leaching behavior among P-adsorbed LDH, ammonia-treated LDH, and pure struvite samples demonstrates that ammonia desorption probably weakened the interaction between phosphate species and LDH cationic layers, thus enhancing the bioavailability of P in LDH adsorbents. The ammonia-treated LDH has a high potential to serve like struvite as a P slow-releasing fertilizer.


Asunto(s)
Fertilizantes , Fósforo , Adsorción , Hidróxidos , Estruvita
8.
Talanta ; 189: 92-99, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-30086981

RESUMEN

Trypsin, as one of important proteases, is specific for catalyzing the hydrolysis of peptide and ester bonds containing lysine and arginine residues at the C-terminus. The level of trypsin in biological fluids can serve as a reliable and specific diagnostic biomarker for pancreatic function and its pathological changes. Herein, we demonstrate the application of phosphorescent Cu NCs for trypsin detection for the first time depending on the electron transfer between Cu NCs and cyt c. Cyt c and Cu NCs were selected as the quencher and the fluorophore, respectively. Cu NCs could bind to the positively charged cyt c through electrostatic and hydrophobic interactions, and the phosphorescence of Cu NCs was efficiently quenched by the metal-containing heme of cyt c. In the presence of trypsin, cyt c was digested, thus phosphorescence of Cu NCs remained. Therefore, a new and continuous phosphorescence assay for the detection of trypsin activity and its inhibitor screening was established. The plot of relative fluorescence versus trypsin concentration obtains a good linear detection range from 0 to 20 ng/mL (R2 = 0.9657), and a detection limit of 2 ng/mL, which is much lower than 20 ng/mL of the sensor in buffer solution because of urine amplifying the phosphorescence signal of Cu NCs based on the FRET strategy. This assay still has been successfully applied to trypsin inhibitor screening, demonstrating its potential application in drug discovery.


Asunto(s)
Cobre/química , Citocromos c/metabolismo , Pruebas de Enzimas/métodos , Límite de Detección , Nanoestructuras/química , Inhibidores de Tripsina/farmacología , Tripsina/metabolismo , Animales , Cobre/metabolismo , Evaluación Preclínica de Medicamentos/métodos , Transporte de Electrón , Humanos , Sustancias Luminiscentes/química , Sustancias Luminiscentes/metabolismo , Tripsina/orina
9.
Mol Med Rep ; 15(4): 2029-2038, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28260016

RESUMEN

Ginsenoside Rg3, a bioactive constituent isolated from Panax ginseng, exhibits antitumorigenic, antioxidative, antiangiogenic, neuroprotective and other biological activities are associated with the regulation of multiple genes. DNA methylation patterns, particularly those in the promoter region, affect gene expression, and DNA methylation is catalyzed by DNA methylases. However, whether ginsenoside Rg3 affects DNA methylation is unknown. High performance liquid chromatography assay, MspI/HpaII polymerase chain reaction (PCR) and reverse transcription­quantitative PCR were performed to assess DNA methylation. It was demonstrated that 20(S)­ginsenoside Rg3 treatment resulted in increased inhibition of cell growth, compared with treatment with 20(R)­ginsenoside Rg3 in the human HepG2 hepatocarcinoma cell line. It was additionally revealed that treatment with 20(S)­ginsenoside Rg3 reduced global genomic DNA methylation, altered cystosine methylation of the promoter regions of P53, B cell lymphoma 2 and vascular endothelial growth factor, and downregulated the expression of DNA methyltransferase (DNMT) 3a and DNMT3b more than treatment with 20(R)­ginsenoside Rg3 in HepG2 cells. These results revealed that the modulation of DNA methylation may be important in the pharmaceutical activities of ginsenoside Rg3.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Metilación de ADN/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Ginsenósidos/farmacología , Neoplasias Hepáticas/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Proliferación Celular/efectos de los fármacos , ADN (Citosina-5-)-Metiltransferasa 1 , ADN (Citosina-5-)-Metiltransferasas/genética , ADN Metiltransferasa 3A , Ginsenósidos/química , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Panax/química , ADN Metiltransferasa 3B
10.
Langmuir ; 25(17): 10189-94, 2009 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-19548635

RESUMEN

The use of microwave irradiation to accelerate both inorganic and organic chemical reactions has attracted widespread attention. Generally, microwave-mediated synthesis of quantum dots (QDs) has been conducted in aqueous solution. Here, using commercial diesel and glycerol as reaction medium, a microwave-mediated nonaqueous method toward CdSe QDs with size-tunable photoluminescent properties produces oleic-acid-protected QDs at moderate reaction temperatures of 50-140 degrees C, which are much lower than the current temperature necessary for the synthesis of CdSe QDs in organic solvents. The appropriate condition optimization for high-quality CdSe QDs shows that different sizes of CdSe QDs with emission wavelengths between 450 and 600 nm have been synthesized through varying time, temperature, feed ratio, and reaction medium.


Asunto(s)
Microondas , Nanotecnología/métodos , Puntos Cuánticos , Cadmio/química , Cristalización , Metales , Microscopía Electrónica de Transmisión/métodos , Óxidos/química , Fotoquímica/métodos , Selenio/química , Solventes/química , Espectrofotometría Ultravioleta/métodos , Temperatura , Factores de Tiempo , Agua/química
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