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1.
Mol Ther ; 31(9): 2734-2754, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37415332

RESUMO

Gastrin-releasing peptide (GRP) binds to its receptor (GRP receptor [GRPR]) to regulate multiple biological processes, but the function of GRP/GRPR axis in acute kidney injury (AKI) remains unknown. In the present study, GRPR is highly expressed by tubular epithelial cells (TECs) in patients or mice with AKI, while histone deacetylase 8 may lead to the transcriptional activation of GRPR. Functionally, we uncovered that GRPR was pathogenic in AKI, as genetic deletion of GRPR was able to protect mice from cisplatin- and ischemia-induced AKI. This was further confirmed by specifically deleting the GRPR gene from TECs in GRPRFlox/Flox//KspCre mice. Mechanistically, we uncovered that GRPR was able to interact with Toll-like receptor 4 to activate STAT1 that bound the promoter of MLKL and CCL2 to induce TEC necroptosis, necroinflammation, and macrophages recruitment. This was further confirmed by overexpressing STAT1 to restore renal injury in GRPRFlox/Flox/KspCre mice. Concurrently, STAT1 induced GRP synthesis to enforce the GRP/GRPR/STAT1 positive feedback loop. Importantly, targeting GRPR by lentivirus-packaged small hairpin RNA or by treatment with a novel GRPR antagonist RH-1402 was able to inhibit cisplatin-induced AKI. In conclusion, GRPR is pathogenic in AKI and mediates AKI via the STAT1-dependent mechanism. Thus, targeting GRPR may be a novel therapeutic strategy for AKI.


Assuntos
Injúria Renal Aguda , Cisplatino , Animais , Camundongos , Cisplatino/efeitos adversos , Necroptose , Injúria Renal Aguda/metabolismo , Rim/metabolismo , Inflamação/metabolismo , Camundongos Endogâmicos C57BL
2.
AAPS PharmSciTech ; 23(6): 181, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35773548

RESUMO

Etoposide (ETO), a traditional anticancer chemotherapeutic agent, is commercialized in oral soft gelatin capsules and non-aqueous parenteral solutions form. Novel formulation application and new excipients exploration are needed to improve the water-solubility and comfort of the drug administration. In the present study, novel etoposide-loaded submicron emulsions (ESE) with the biosurfactants of acidic sophorolipid (ASL) and lactonic sophorolipid (LSL) instead of the chemical surfactant of Tween-80 were prepared and characterized. Firstly, parameters of medium-chain triglyceride: long-chain triglyceride (MCT:LCT), lecithin concentration, homogenization pressure and cycle, and type and concentration of surfactants were investigated to optimize the formation of ESEs. Then the physicochemical properties, antitumor activity, stability, and security of ESEs were compared. The results showed that ASL performed the best properties and activities than Tween-80 and LSL in ESE formation. ASL-ESE showed higher drug loading capacity, slower release rate, and significantly increased antitumor activity against ovarian cancer cell line A2780 via apoptosis than Tween-ESE and commercial ETO injection. Besides, both ASL-ESE and Tween-ESE caused no hemolysis, and the safe dose of ASL was 2.14-fold that of Tween-80 in the hemolysis test, making ASL more reliable for drug delivery applications. Furthermore, ASL-ESE exhibited equivalent long-term and autoclaving stability to Tween-ESE. These results thus suggested the excellent competences of ASL in ESE formation, efficacy enhancement, and safety improvement.


Assuntos
Antineoplásicos , Neoplasias Ovarianas , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Estabilidade de Medicamentos , Emulsões/química , Etoposídeo , Excipientes , Feminino , Humanos , Ácidos Oleicos , Polissorbatos , Tensoativos/química , Triglicerídeos/química
3.
Bioorg Chem ; 124: 105794, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35533545

RESUMO

The side effects of acute Kidney Injury (AKI) and nephrotoxicity limit the application of cisplatin in cancer treatment. Inflammation and oxidative stress paly important role in the pathogenesis of cisplatin-induced AKI. Gastrin-releasing peptide receptor (GRPR) plays an important role in inflammatory response. In this study, we designed 34 new Pd176252 analogs, most synthesized compounds could reduce cisplatin-induced HK2 cell death. Of these compounds, 9b had strong binding affinity with GRPR, and significantly increased HK2 cell viability. Compound 9b significantly downregulated the level of creatinine, blood urea nitrogen (BUN), and malondialdehyde (MDA), and recovered the glutathione (GSH) level in cisplatin-induced AKI model. It also decreased the level of kidney injury molecule-1(KIM-1) in vitro and vivo. In the further pathogenesis studies, 9b downregulated level of inflammatory factors (TNF-α, IL-1ß, IL-6 and MCP-1), suppressed the nuclear factor-kappa B (NF-kB) phosphorylation, and decreased GRPR level. The results suggested that ameliorating cisplatin-induced AKI actions of 9b was involved in downregulation of TNF-α, IL-1ß, IL-6, and MCP-1, inhibition of NF-kB activation, and reduction of GRPR and oxidative stress level.


Assuntos
Injúria Renal Aguda , Cisplatino , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/prevenção & controle , Apoptose , Cisplatino/farmacologia , Glutationa/metabolismo , Humanos , Interleucina-6/metabolismo , Rim , NF-kappa B/metabolismo , Estresse Oxidativo , Receptores da Bombesina/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
4.
Anticancer Agents Med Chem ; 22(17): 3009-3024, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35490428

RESUMO

BACKGROUND: GRPR is over-expressed in cancer cells and is a potential drug target for the treatment of cancer. PD176252, as the most representative non-peptide inhibitor of GRPR, can inhibit the growth of cancer cells, but its low selectivity to cancer cells and normal cells limits its further application. OBJECTIVE: The aim of this study was to design and synthesize novel GRPR inhibitor with stronger anti-cancer activity and higher affinity with GRPR than the lead compound PD176252. METHODS: A series of 1, 3, 4-oxadiazole derivatives as PD176252 analogues (4a-4j, 6a-6q) were synthesized and their cytotoxic activity was investigated on four cancer lines with high expression of GRPR (gastric (HGC-27), colon (HCT- 116), prostate (PC-3), and lung (A549)) and one human cell line (gastric mucosal epithelial (GES-1)) by MTT assay. Flow cytometry analysis and Western Blot were used to determine whether the compound induced programmed apoptosis of cancer cells. Competitive binding experiment was used to verify the affinity between GRPR and the optimal compound. RESULTS: Compound 6m exhibited significant growth inhibition on all tested cancer cell lines, especially gastric cancer cells (HGC-27 cellular IC50 0.37 ± 0.04µM). Also, the selectivity of 6m to HGC-27 was much higher than that of PD176252. Flow cytometric analysis and Western Blot proved that 6m significantly promoted the apoptosis of HGC- 27 cells. Moreover, competitive binding experiment confirmed the close binding of 6m with GRPR, which indicated 6m with a higher affinity than lead compound PD176252. CONCLUSION: Our results suggested that 6m, as a novel GRPR inhibitor, had a higher affinity with GRPR and potential anti-cancer effect than PD176252, which can be used as a template for further optimization.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/química , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Indóis/farmacologia , Masculino , Oxidiazóis/farmacologia
5.
Anticancer Agents Med Chem ; 22(10): 1945-1961, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34674626

RESUMO

BACKGROUND: Chalcone is a broad-spectrum natural product with anti-cancer and anti-inflammatory activities. However, low potency, low selectivity, and serious side effects limit its druggability. L-Tryptophan is an essential precursor molecule of an anti-cancer active substance. Also, the indole moiety inhibits the proliferation of tumor cells by binding to colchicine sites. A decrease in kidney cell activity caused by kidney inflammation is the primary side effect of cancer therapy. OBJECTIVE: The purpose of this work was to design, synthesize, and perform bioactivity evaluation of novel chalcone derivatives possessing tryptophan moiety with dual activities of anti-cancer and partially restoring the proliferation of normal kidney cells pre-treated with cisplatin. METHODS: A series of novel chalcone derivatives possessing tryptophan moiety (5a-5g, 6a-6o) were designed, synthesized, and evaluated for anti-cancer activity against four cancer cell lines (gastric (HGC-27), colon (HCT-116), prostate (PC-3), and lung (A549)), and a human normal cell line (gastric mucosal epithelial (GES-1)). The activity of restoring the proliferation of normal kidney cells pre-treated with cisplatin was evaluated by MTT assay. Cell cycle, apoptosis, and apoptosis proteins (Bax and Bcl-2) were used to evaluate the anti-cancer mechanism of the most potent compound. Moreover, a docking study was performed to explain the high anti-cancer activity of 6n. The expressions of TNF-α, IL- 6, and MCP-1 were detected by ELISA. RESULTS: Most of the compounds exhibited high anti-cancer activity against the HGC-27 cell line and exhibited low toxicity against the normal cell line. Based on three rounds of a structure optimization, 6n was discovered as the most potent compound against HGC-27 cells with an IC50 value of 2.02 µM and an SI value of 28.47. Further studies demonstrated that 6n could induce cell cycle arrest at the G2/M phase and the apoptosis of the HGC-27 cell line by reducing the expression of Bcl-2 and improving the expression level of Bax. Molecular docking result displayed 6n bound to the colchicine site. At the same time, 6n also exhibited moderate activity of restoring the proliferation of normal kidney cells pre-treated with cisplatin by reducing the expression of inflammatory substances. CONCLUSION: Our findings collectively suggested that 6n should be further studied as a potential anti-cancer agent that could partially restore the proliferation of normal kidney cells pre-treated with cisplatin in gastric cancer patients by an anti-inflammatory pathway.


Assuntos
Antineoplásicos , Chalcona , Chalconas , Antineoplásicos/química , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Chalcona/farmacologia , Chalconas/química , Cisplatino/farmacologia , Colchicina/farmacologia , Relação Dose-Resposta a Droga , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Rim , Masculino , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade , Triptofano/farmacologia , Proteína X Associada a bcl-2
6.
Prep Biochem Biotechnol ; 51(9): 833-841, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33427036

RESUMO

Cinnamaldehyde (CA) is one of the major active pharmaceutical ingredient of cinnamon bark. Hydrodistillation (HD) is usually used in CA extraction, however, the extraction yield is lower. The cell wall is a key factor limiting the extraction of essential oils. In-situ reactive heat breaking cell wall (RHB) could destroy the cell wall, which was conducive to the diffusion of CA. The aim of this work was to examine the effect of RHB pretreatment to HD extraction. Response surface methodology (RSM) was used to optimize RHB pretreatment parameters, and Box-Behnken Design (BBD) method was performed to evaluate the effects of different operating parameters. The maximum yield was increased to 3.31 ± 0.11% (w/w) from 2.08 ± 0.042% (w/w) after RSM optimization. Scanning electron microscopic (SEM) analysis showed that RHB destroyed and disrupted the cell wall of cinnamon bark. The GC analysis demonstrated that the purity of cinnamaldehyde was improved and no new components were presented in the extraction product from the cinnamon via RHB pretreatment. In conclusion, RHB is an effective pretreatment method for the CA extraction, and also may be used in the other herbal medicine extraction.


Assuntos
Parede Celular/química , Cinnamomum zeylanicum/química , Temperatura Alta , Óxidos de Enxofre/química , Acroleína/análogos & derivados , Acroleína/química , Acroleína/isolamento & purificação
7.
Bioprocess Biosyst Eng ; 43(10): 1869-1883, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32447514

RESUMO

To enhance specific or total sophorolipids (SLs) production by Starmerella bombicola for specific application, mutant library consisting of 106 mutants from 7 batches was constructed via atmospheric and room-temperature plasma (ARTP). When compared to the wild strain, 11, 36 and 12 mutants performed increases over 30% in lactonic, acidic or total SLs production. Genetic stability investigation showed that 8, 7, and 4 mutants could maintain the improved SLs production capacity. Mutants of A6-9 and A2-8 were selected out for enhanced specific SLs and total SLs production in fed-batch cultivation in flask. Without optimization, A6-9 obtained the highest reported lactonic SLs production of 51.95 g/l and A2-8 performed comparable acidic and total SLs production of 68.75 g/l and 100.33 g/l with all the reported stains. The structural composition of the obtained SLs was analyzed by HPLC and LC/MS, and the results confirmed the enhancement of SLs and certain SL components. These mutants would be important in industrial applications because the production and purification costs of SLs could be greatly reduced. Besides, the acquisition of these mutants also provided materials for the investigation of regulation mechanism of SLs biosynthesis for further genetic engineering of S. bombicola. Furthermore, critical micelle concentration (CMC), minimum surface tension (STmin) and hydrophilic-lipophilic balance (HLB) of the SLs obtained from the wild and mutant strains were also examined and compared. These results demonstrated the feasibility of obtaining SLs with different properties from different strains and the high efficiency of mutation breeding of S. bombicola by ARTP.


Assuntos
Mutação , Ácidos Oleicos/biossíntese , Gases em Plasma/farmacologia , Saccharomycetales , Ácidos Oleicos/genética , Saccharomycetales/genética , Saccharomycetales/metabolismo
8.
Iran J Biotechnol ; 18(3): e2461, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33850944

RESUMO

BACKGROUND: Lignin is the largest natural aromatic polymer in nature and is also a unique aromatic-based biopolymer, accounting for nearly 30% of the earth's organic carbon. Generally, lignin is regarded as waste and is mainly used as a low- value fuel that is burned to generate heat and energy to solve the problem of biomass waste; for this obstacle of lignin, highly efficient biodegradation plays a critical role in developing an environmentally friendly technique for lignin biotransformation. OBJECTIVES: This study intends to isolate and purify several microbial strains from nature. It also explores how their lignin degradation is able to enhance the biodegradation and recycling of biomass and the reclamation of lignin in wastewater from pulp and paper mills. MATERIALS AND METHODS: Lignin-degrading microbial strains were isolated from soil using medium containing sodium lignosulphonate as the sole carbon source. They were then screened by aniline blue and guaiacol plate, and then the best strain was chosen and identified. The conventional one-factor method was used to optimize various parameters that affect lignin's degradation ability. RESULTS: The strain possessing the highest lignin biodegradation ability was identified and denominated as Aspergillus Flavus F-1. After optimization, the maximum degradation rate of lignin, 44.6% within 3 days, was obtained at pH 7.0, 30 ℃, 2.5 g·L-1 ammonium sulfate, 2 g·L-1 lignin and 0.5 g·L-1 glucose. The results show the LiP and Lac secreted from Aspergillus Flavus F-1 played the main role in the degradation of lignin. CONCLUSION: One microbial strain, Aspergillus Flavus F-1, was successfully isolated with a lignin-degrading ability that can cut the lignin into fragments. This provides a promising candidate for the transformation and utilization of crop waste biomass for various industrial purposes.

9.
Appl Microbiol Biotechnol ; 104(1): 77-100, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31776606

RESUMO

Sophorolipids (SLs), mainly synthesized by yeasts, were a sort of biosurfactant with the highest fermentation level at present. In recent years, SLs have drawn extensive attention for their excellent physiochemical properties and physiological activities. Besides, issues such as economics, sustainability, and use of renewable resources also stimulate the shift from chemical surfactants towards green or microbial-derived biosurfactants. SLs' large-scale production and application were restricted by the relatively high production costs. Currently, waste streams from agriculture, food and oil refining industries, etc., have been exploited as low-cost renewable substrates for SL production. Advanced cultivation method, uncommonly used substrates, and new genetically modified SL-producing mutants were also designed and applied to improve the productivity or the special properties of SLs. In this review, a systematic and detailed description of primary and secondary metabolism pathways involved in SL biosynthesis was summarized firstly. Furthermore, based on the pathways of SL biosynthesis from different carbon substrates, we reviewed the current knowledge and advances in the exploration of cost-effective and infrequently used hydrophilic and hydrophobic substrates for large or specialized SL production.


Assuntos
Vias Biossintéticas , Carbono/metabolismo , Ácidos Oleicos/biossíntese , Metabolismo Secundário , Leveduras/metabolismo , Fermentação , Interações Hidrofóbicas e Hidrofílicas
10.
Medchemcomm ; 10(5): 757-763, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31191866

RESUMO

Cisplatin is a clinical chemotherapy drug for cancers; however, its remarkably high kidney toxicity and other toxicities pose a danger to patients. As the small molecule inhibitor of GRPR, PD176252 can inhibit the growth and proliferation of various cancer cells, but the characteristics of high toxicity and poor water solubility has limited its use as a drug. When we studied PD176252 for the reduction of toxicity of cisplatin, we modified its structure to synthesize 16 analogues. Surprisingly, the analogues showed reduced cisplatin-induced renal toxicity, and unlike PD176252, the analogues 5d and 5m were almost non-toxic to the normal HK2 cells. Furthermore, the analogue 5d and PD176252 were subjected to cisplatin-induced inflammatory response in vitro. The results showed that 5d was able to better prevent this condition by effectively inhibiting its inflammatory response. Thus, this study will help in clinically reducing the side effects of cisplatin.

11.
Anticancer Agents Med Chem ; 19(8): 992-1001, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30961511

RESUMO

BACKGROUND: Cancer patients treated with targeted anti-cancer drug suffer from itch or pruritus. Itch or pruritus is an unpleasant sensation that brings about a negative impact on quality of life, and serious itch may lead to dose reduction and even discontinuation. Gastrin releasing peptide receptor (GRPR) plays a critical role in itch, inflammation and cancer, and GRPR antagonist has obvious effect on cancer, inflammation and itch. The aim of this paper is to develop a new agent with anti-cancer and anti-itch activity. METHODS: A series of GRPR antagonist PD176252 analogues (3a-3l) were designed and synthesized. Both anticancer and anti-itch activities were evaluated. Anti-cancer activity was evaluated in three human cancer cell lines in vitro, the anti-itch activity in evaluated with Kunming mice by intrathecal injection of chloroquine phosphate as a modeling medium. And the cytotoxicity on normal cells was evaluated. RESULTS: Of the tested compounds, compound 3i showed potently anti-cancer activity to all cancer cell lines tested with IC50 values of 10.5µM (lung), 11.6µM (breast) and 12.8µM (liver) respectively and it also showed significant inhibition of the scratching behavior. Comparing with PD17625, compound 3i and 3g gave better inhibition activities against all cancer cell lines, compound 3b, 3c and 3i showed better anti-itch activity. The compound 3i is safe for normal breast and liver normal cells, but it has high cytotoxicity on normal lung cell. CONCLUSION: The synthesized compounds have dual anti-cancer and anti-itch activity, so the development of drug with dual anti-tumor and anti-itch property is possible.


Assuntos
Antineoplásicos/farmacologia , Antipruriginosos/farmacologia , Desenho de Fármacos , Indóis/farmacologia , Prurido/tratamento farmacológico , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antipruriginosos/síntese química , Antipruriginosos/química , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Indóis/síntese química , Indóis/química , Masculino , Camundongos , Camundongos Endogâmicos , Estrutura Molecular , Relação Estrutura-Atividade , Células Tumorais Cultivadas
12.
J Antibiot (Tokyo) ; 71(4): 477-479, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29402998

RESUMO

A new macrolactam derivative, designated as nivelactam B (1), was isolated from the fermentation broth of marine-derived actinomycete HF-11225. Its structure was determined on the basis of spectroscopic analysis, including 1D and 2D NMR techniques, as well as ESI-MS and comparison with data from the literature. Compound 1 showed weak cytotoxic and antifungal activities.


Assuntos
Actinobacteria/metabolismo , Antibacterianos/biossíntese , Antifúngicos/química , Lactamas Macrocíclicas/química , Antibacterianos/química , Antibacterianos/farmacologia , Antibióticos Antineoplásicos/farmacologia , Antifúngicos/farmacologia , Linhagem Celular Tumoral , Humanos , Lactamas Macrocíclicas/farmacologia , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
13.
Chem Pharm Bull (Tokyo) ; 66(4): 410-415, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29415905

RESUMO

The anti-inflammatory effects of (R)-2-(1H-Imidazol-1-yl) ethyl-3-(1H-indol-3-yl)-2-(2-p-tolylacetamido)propanamide (RH-1402), a previous designed small molecule Gastrin releasing peptide (GRP) antagonist were evaluated in adjuvant-induced arthritic model of rats, and the inhibitory effect on neutrophil migration induced by GRP was determined by a transwell system experiment in vitro. The arthritis was induced by injection of Complete Freund's Adjuvant (CFA) containing 10 mg/mL of heat killed mycobacterium into the left hind footpad. Experimental rats were randomly divided into 6 groups, including control, placebo, positive control group, RH-1402 of low/middle/high dose group. Disease incidence and severity was evaluated through scoring of the paw edema and histologic features of joint synovial. Blood of all experimental rats was collected for interleukin 1ß (IL-1ß) and tumor necrosis factor α (TNF-α) cytokine levels. A transwell system was used to investigate whether RH-1402 would inhibit neutrophils migrating up a gradient of GRP in vitro. RH-1402 (5 and 10 mg/kg) significantly decreased adjuvant induced increased arthritis index during the administration period (days 14-20). Significant inhibition of joint synovial histological features can be found in the RH-1402 treated group, including alleviated Hyperplasia, Inflammatory of infiltration and activation of pannus formation. It also suppressed TNF-α and IL-1ß level. Five and 10 mg/kg of RH-1402 significantly inhibited the effect of GRP on neutrophil migration with a dose dependent relationship. These findings indicate that RH-1402 have potential protective anti-inflammatory effects on experimental models of arthritis.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Artrite Experimental/tratamento farmacológico , Receptores da Bombesina/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Artrite Experimental/induzido quimicamente , Artrite Experimental/patologia , Adjuvante de Freund/administração & dosagem , Ratos , Ratos Sprague-Dawley , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/química
14.
J Environ Sci (China) ; 53: 132-140, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28372737

RESUMO

Lignocellulosic biomass offers the most abundant renewable resource in replacing traditional fossil resources. However, it is still a major challenge to directly convert the lignin component into value-added materials. The availability of plentiful hydroxyl groups in lignin macromolecules and its unique three-dimensional structure make it an ideal precursor for mesoporous biosorbents. In this work, we reported an environmentally friendly and economically feasible method for the fabrication of mesoporous lignin-based biosorbent (MLBB) from lignocellulosic biomass through a SO3 micro-thermal-explosion process, as a byproduct of microcrystalline cellulose. BET analysis reveal the average pore-size distribution of 5.50nm, the average pore value of 0.35cm3/g, and the specific surface area of 186m2/g. The physicochemical properties of MLBB were studied by fourier transform infrared spectroscopy (FTIR), attenuated-total-reflection fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), and element analysis. These results showed that there are large amounts of sulfonic functional groups existing on the surface of this biosorbent. Pb(II) was used as a model heavy-metal-ion to demonstrate the technical feasibility for heavy-metal-ion removal. Considering that lignocellulosic biomass is a naturally abundant and renewable resource and SO3 micro-thermal-explosion is a proven technique, this biosorbent can be easily produced at large scale and become a sustainable and reliable resource for wastewater treatment.


Assuntos
Filtração/instrumentação , Lignina/química , Metais Pesados/química , Modelos Químicos , Adsorção , Celulose/química , Cinética , Oryza , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier
15.
AMB Express ; 6(1): 60, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27568226

RESUMO

A novel lignocellulose material, holocellulose from rice straw via the pretreatment of SO3 micro-thermal explosion, was developed to produce sophorolipids (SLs) with Wickerhamiella domercqiae var. sophorolipid CGMCC 1576. The influence factors of inoculum dose, yeast extract concentration and pH regulators (chemical regents used for adjusting/influencing pH) was investigated and discussed. Results showed that W. domercqiae can grow in the rice straw holocellulose hydrolysate, and acquire relative high SL yield of 53.70 ± 2.61 g/L in shake flask culture. Inoculum dose, yeast extract concentration and pH regulator made obvious influence on fermentation parameters, especially on final broth pH and SLs production. Furthermore, there is a strong negative linear correlation existing between final broth pH and lactonic SL or ratio of lac SL/tot SL. Additionally, comparison between SL production and non-glucose carbon sources, culture methods, microbes in previous reports was carried out. These results will be benefit for acquiring SL mixture with suitable lac SL/tot SL ratio for specific purpose and scope economically.

16.
Chem Biodivers ; 12(1): 116-32, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25641840

RESUMO

Due to the rising incidence and lack of effective treatments, malignant melanoma is the most dangerous form of skin cancer, so that new treatment strategies are urgently needed. Several recent developments indicate that the V600E mutant BRAF (BRAF(V600E) ) is a validated target for antimelanoma-drug development. Based on in silico screening results, a series of novel pyrazole derivatives has been designed, synthesized, and evaluated in vitro for their inhibitory activities against BRAF(V600E) melanoma cells. Compound 3d exhibited the most potent inhibitory activity with an IC50 value of 0.63 µM for BRAF(V600E) and a GI50 value of 0.61 µM for mutant BRAF-dependent cells. Furthermore, the QSAR modeling and the docking simulation of inhibitor analogs provide important pharmacophore clues for further structural optimization.


Assuntos
Descoberta de Drogas , Melanoma/tratamento farmacológico , Pirazóis/farmacologia , Neoplasias Cutâneas/tratamento farmacológico , Humanos , Melanoma/genética , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Pirazóis/química , Pirazóis/uso terapêutico , Neoplasias Cutâneas/genética
17.
Org Lett ; 16(20): 5462-5, 2014 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-25296160

RESUMO

A novel chemoselective phosphine-mediated tandem reaction between nonsubstituted MBH carbonates and aryl trifluoromethyl ketones is described. The product selectivity of the reaction is easily tunable by changing the ratios of the two reactants, and mono- or bicyclic bistrifluoromethylated vinyl γ-butenolide products can be prepared with good chemoselectivity in modest-to-good yields and diastereoselectivities. The formation of the bicyclic γ-butenolide structures via a one-pot four-step sequence under phosphine catalysis is unprecedented.


Assuntos
4-Butirolactona/análogos & derivados , Carbonatos/química , Hidrocarbonetos Fluorados/química , Cetonas/química , Fosfinas/química , 4-Butirolactona/síntese química , 4-Butirolactona/química , Catálise , Estrutura Molecular , Estereoisomerismo
18.
Chem Commun (Camb) ; 50(67): 9477-80, 2014 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-25007971

RESUMO

A bis-alkynylplatinum(II) terpyridine tweezer-alkynylgold(III) diphenylpyridine guest is shown to maintain the specific complexation in the presence of a B21C7-secondary ammonium salt recognition motif, which facilitates the formation of supramolecular hyperbranched polymers via the "tweezering directed self-assembly" strategy.


Assuntos
Compostos Organoplatínicos/química , Polímeros/química , Piridinas/química , Modelos Moleculares , Conformação Molecular , Polimerização
19.
Org Lett ; 16(12): 3180-3, 2014 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-24890791

RESUMO

A platinum(II) acetylide-based bolaamphiphile equipped with two peripheral B18C6 moieties has been successfully prepared, which demonstrates cooperative recognition behavior toward l-alanine ester salt in chloroform. In a polar methanol/chloroform (3/1, v/v) medium, the amino acid additives influence the aggregation of the bolaamphiphile significantly, leading to the morphological transition from nanospherical to disordered structures. The adaptive properties of the current host-guest binary system will benefit the development of stimuli-responsive supramolecular materials.


Assuntos
Aminoácidos/química , Furanos/química , Compostos Organoplatínicos/síntese química , Piridonas/química , Alanina/química , Clorofórmio , Ésteres , Metanol/química , Estrutura Molecular , Compostos Organoplatínicos/química , Estereoisomerismo
20.
ACS Nano ; 8(5): 4848-58, 2014 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-24730360

RESUMO

Current nanoparticle-based gene delivery techniques face two major limitations, namely, endosomal degradation and poor cytosolic release of the nanoparticles and nonspecificity of treatment. These limitations can be overcome with certain light-based techniques, such as photochemical internalization to enable endosomal escape of the delivered nanoparticles and light-controlled gene expression to overcome the nonspecific effects. However, these techniques require UV/visible light, which is either phototoxic and/or has low tissue penetration capabilities, thus preventing their use in deep tissues in a clinical setting. In an effort to overcome these barriers, we have successfully demonstrated a light-based gene delivery system that significantly boosts cytosolic gene delivery, with precise control over gene expression and the potential for use in nonsuperficial tissues. Core-shell fluorescent upconversion nanoparticles excited by highly penetrating near-infrared radiation and emitting simultaneously in the ultraviolet and visible ranges were synthesized and used as remote nanotransducers to simultaneously activate endosomal escape and gene knockdown. Gene knockdown using photomorpholinos was enhanced as much as 30% in vitro compared to the control without endosomal escape facilitation. A similar trend was seen in vivo in a murine melanoma model, demonstrating the enormous clinical potential of this system.


Assuntos
Endossomos/metabolismo , Técnicas de Silenciamento de Genes , Técnicas de Transferência de Genes , Nanotecnologia/métodos , Espectroscopia de Luz Próxima ao Infravermelho , Animais , Sobrevivência Celular , Citosol/metabolismo , Ensaio de Imunoadsorção Enzimática , Corantes Fluorescentes/química , Luz , Teste de Materiais , Melanoma/metabolismo , Melanoma Experimental , Camundongos , Nanopartículas/química , Fármacos Fotossensibilizantes/química , Espécies Reativas de Oxigênio/metabolismo , Raios Ultravioleta
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