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1.
J Sep Sci ; 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34799974

RESUMO

Black bean, in which isoflavones are the main active constituent, also contains saponins, and monoterpenes. Soybean isoflavone is a secondary metabolite that is formed during the growth of soybean; it exhibits antioxidant and cardiovascular activities and traces estrogen-like effects. In this study, black bean isoflavones were extracted with n-butanol, and ultrafiltration-liquid chromatography-mass spectrometry was used to screen their activity. Subsequently, the inhibitors were isolated and purified using semi-preparative liquid chromatography and stepwise flow-rate counter-current chromatography. Thereafter, five active compounds were identified using mass spectrometry and nuclear magnetic resonance experiments. Lastly, the inhibition types of the xanthine oxidase inhibitors were determined using enzymatic kinetic studies. The IC50 values of daidzin, glycitein-7-O-glucoside, genistin, daidzein, and genistein were determined to be 35.08, 56.22, 30.76, 68.79, and 95.37 µg/mL, respectively. Daidzin, genistin, and daidzein exhibited reversible inhibition, whereas glycitein-7-O-glucoside and genistein presented irreversible inhibition. This novel approach, which was based on ultrafiltration-liquid chromatography-mass spectrometry and stepwise flow-rate counter-current chromatography, is a powerful method for screening and isolating xanthine oxidase inhibitors from complex matrices. The study of enzyme inhibition types is helpful for understanding the underlying inhibition mechanism. Therefore, a beneficial platform was developed for the large-scale production of bioactive and nutraceutical ingredients. This article is protected by copyright. All rights reserved.

2.
Cell Rep ; 37(1): 109785, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34610303

RESUMO

A hallmark of type 2 diabetes (T2D) is hepatic resistance to insulin's glucose-lowering effects. The serum- and glucocorticoid-regulated family of protein kinases (SGK) is activated downstream of mechanistic target of rapamycin complex 2 (mTORC2) in response to insulin in parallel to AKT. Surprisingly, despite an identical substrate recognition motif to AKT, which drives insulin sensitivity, pathological accumulation of SGK1 drives insulin resistance. Liver-specific Sgk1-knockout (Sgk1Lko) mice display improved glucose tolerance and insulin sensitivity and are protected from hepatic steatosis when fed a high-fat diet. Sgk1 promotes insulin resistance by inactivating AMP-activated protein kinase (AMPK) via phosphorylation on inhibitory site AMPKαSer485/491. We demonstrate that SGK1 is dominant among SGK family kinases in regulation of insulin sensitivity, as Sgk1, Sgk2, and Sgk3 triple-knockout mice have similar increases in hepatic insulin sensitivity. In aggregate, these data suggest that targeting hepatic SGK1 may have therapeutic potential in T2D.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34511352

RESUMO

OBJECTIVE: Plate exposure remains one of the most serious complications of oromandibular reconstruction. The purpose of this study was to investigate the effect of wrapping reconstruction plates with anterolateral thigh (ALT) free flaps as a way to prevent plate exposure. STUDY DESIGN: A total of 91 patients with composite oromandibular defects who underwent surgical reconstruction using a reconstruction plate in conjunction with an ALT musculocutaneous flap were recruited. The participants were divided into 2 groups, based on whether the plate was wrapped with or covered by the ALT flap. RESULTS: The incidence of plate exposure in the experimental group (17%) was significantly lower than that of the control group (43.1%; P < .0001). The mean time from reconstruction until plate exposure in the experimental group was 19.4 ± 23.6 months, whereas the mean time in the control group was 12.3 ± 9.1 months. In the logistic regression model for the occurrence of plate exposure, the only factor found to be associated with plate exposure was how the ALT flap was used (P = .026). CONCLUSIONS: The results of the present study indicate that wrapping the reconstruction plate with an ALT flap decreased the incidence of plate exposure in patients with oromandibular defects.

4.
BMC Oral Health ; 21(1): 387, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362348

RESUMO

BACKGROUND: Salivary fistula is a relatively common complication in patients who have undergone a parotidectomy. The purpose of this study was to investigate the effects of bipolar coagulation forceps use on salivary fistulas. METHODS: From March 2015 to June 2020, 177 patients who underwent a parotidectomy in the Department of Oral and Maxillofacial Surgery at the Second Xiangya Hospital of Central South University were recruited. The patients were divided into an experimental group and a control group based on whether bipolar coagulation forceps or sutures were used, respectively. RESULTS: The drainage output of the experimental group was significantly lower than that of the control group (p = 0.04). The duration of dressing pressure applied in the experimental group was significantly shorter than that in the control group (p = 0.0003). Moreover, the incidence of salivary fistula in the experimental group (9.8%, 8/82) was notably lower than that in the control group (34.7%, 33/95) (p < 0.0001). In the logistic regression model for salivary fistula development, both the use of bipolar coagulation forceps (p = 0.0021) and drainage output (p = 0.0237) were associated with the presence of salivary fistulas. CONCLUSIONS: Our findings indicate that the use of bipolar coagulation forceps decreases the incidence of salivary fistula in patients who have undergone a parotidectomy. The use of bipolar coagulation forceps is a safe, effective, and convenient method to prevent salivary fistulas in patients who undergo a parotidectomy. TRIAL REGISTRATION: Current Controlled Trials ChiCTR2100044722, Date: 26/03/2021, Retrospectively registered.


Assuntos
Fístula , Complicações Pós-Operatórias , Drenagem , Humanos , Glândula Parótida/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos , Instrumentos Cirúrgicos
5.
Cardiol Res Pract ; 2021: 5574125, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34336272

RESUMO

Objective: To explore the quantitative adjustment of ablation index (AI) under different baseline impedance to achieve similar lesion dimensions. Methods: (1) Keeping the AIs relatively constant, the lesion dimensions in different baseline impedances were studied. (2) According to Joule's law, Q = I 2RT, keeping the current (I) unchanged, the powers corresponding to different baseline impedances can be obtained. Under different baseline impedances and corresponding powers, the swine hearts were ablated for 30 s in simulated human circumstances. The baseline impedances, the lesion dimensions, and AIs were recorded. And the derivation of empirical formula was achieved according to the AIs and baseline impedance values in similar lesions dimension. (3) Basic AI and baseline impedance (AI0/R 0) were set as 400/120 Ω in the common AI groups and 550/120 Ω in the high AI groups, AI values in different baseline impedances were calculated using the empirical formula, and the corresponding lesion dimensions were measured to verify this formula. Results: (1) Higher baseline impedances were related to smaller lesion dimensions at similar AIs. (2) The lesion dimensions were roughly the same after modulating the baseline impedance and power to keep the electric current relatively constant. The relationship between AI and R fitted with experimental data is AI = 1.9933R + 203.61 (r = 0.9649), and the formula derived is ΔAI = (AI0 - 203)/R 0 × ΔR. (3) Under the guidance of the empirical formula, there was no significant difference in lesion dimensions between the standard group and the formula guiding groups when AI0 = 400, but there was a shrinking tendence when AI > 700. Conclusion: The lesion depths are negatively correlated with baseline impedance at a certain AI. The relationship between baseline impedance and AI is "ΔAI = (AI0 - 203)/R 0 × ΔR". It is verified that when the AI is not too high, the empirical formula can be used to guide the quantitative adjustment of AIs at different baseline impedance, and the lesion depths achieved are roughly the same.

6.
Sci Rep ; 11(1): 14024, 2021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34234229

RESUMO

Mounting evidence suggests that microbiota dysbiosis caused by antibiotic administration is a risk factor for cancer, but few research reports focus on the relationships between antibiotics and chemotherapy efficiency. We evaluated the influence of antibiotic administration on neoadjuvant therapy efficacy in patients with breast cancer (BC) in the present study. BC patients were stratified into two groups: antibiotic-treated and control based on antibiotic administration within 30 days after neoadjuvant therapy initiation. Disease-free survival (DFS) and overall survival (OS) were assessed using the Kaplan-Meier method, and the Cox proportional hazards model was used for multivariate analyses. The pathologic complete response rate of the control group was significantly higher than that of the antibiotic-treated group (29.09% vs. 10.20%, p = 0.017). Further univariate analysis with Kaplan-Meier calculations demonstrated that antibiotic administration was strongly linked with both reduced DFS (p = 0.04) at significant statistical levels and OS (p = 0.088) at borderline statistical levels. Antibiotic administration was identified as a significant independent prognostic factor for DFS [hazard ratio (HR) 3.026, 95%, confidence interval (CI) 1.314-6.969, p = 0.009] and OS (HR 2.836, 95% CI 1.016-7.858, p = 0.047) by Cox proportional hazards model analysis. Antibiotics that initiated reduced efficiency of chemotherapy were more noticeable in the HER2-positive subgroup for both DFS (HR 5.51, 95% CI 1.77-17.2, p = 0.003) and OS (HR 7.0395% CI 1.94-25.53, p = 0.003), as well as in the T3-4 subgroup for both DFS (HR 20.36, 95% CI 2.41-172.07, p = 0.006) and OS (HR 13.45, 95% CI 1.39-130.08, p = 0.025) by stratified analysis. Antibiotic administration might be associated with reduced efficacy of neoadjuvant therapy and poor prognosis in BC patients. As a preliminary study, our research made preparations for further understanding and large-scale analyses of the impact of antibiotics on the efficacy of neoadjuvant therapy.


Assuntos
Antibacterianos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Antibacterianos/administração & dosagem , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/etiologia , Neoplasias da Mama/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Microbiota/efeitos dos fármacos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Prognóstico , Tempo para o Tratamento , Resultado do Tratamento
7.
Sheng Wu Gong Cheng Xue Bao ; 37(6): 2077-2084, 2021 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-34227295

RESUMO

Curcumin is exclusively isolated from Zingiberaceae plants with a broad spectrum of bioactivities. In the present study, we used the diketide-CoA synthase (DCS) and curcumin synthase (CURS) genes to construct a non-natural fusion gene encoding diketide-CoA synthase::curcumin synthase (DCS::CURS). This fusion protein, together with the acetyl coenzyme A carboxylase (ACC) and the 4-coumarate coenzyme A ligase (4CL), were introduced into Escherichia coli for the production of curcumin from ferulic acid. The process is divided into two stages, the growth stage using LB medium and the fermentation stage using the modified M9 medium. The yield of curcumin reached 386.8 mg/L by optimizing the induction of protein expression in the growth stage, and optimizing the inoculum volume, medium composition and fermentation time in the fermentation stage, as well as the addition of macroporous resin AB-8 into the second medium to attenuate the toxicity of the end product. The exploitation of the non-natural fusion protein DCS::CURS for the production of curcumin provides a new alternative to further promoting the production of curcumin and the related analogues.


Assuntos
Curcumina , Escherichia coli , Curcumina/farmacologia , Escherichia coli/genética , Fermentação
8.
J Sep Sci ; 44(15): 2875-2887, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34043286

RESUMO

An efficient method based on ultrafiltration high-performance liquid chromatography coupled with photodiode array detector and electrospray ionization mass spectrometry for the rapid screening and identified of the ligands for activated from the extract of Trifolium repens L. Five major compounds, namely ononin, daidzein, genistein, formononetin, and biochanin A, were identified as potentially effective inhibitors. Subsequently, the specific binding ligands were separated by stepwise flow rate high-speed countercurrent chromatography and semipreparative high-performance liquid chromatography. This is the first report that T. repens extracts contain potent lipoxidase inhibitors. In summary, we systematically studied the active components in T. repens, evaluated their activity, separated and purified them, and identified their structure. This method is simple, fast, and efficient. It is suitable for the separation and purification of active compounds in T. repens, and provides a theoretical basis and technical platform for the development of natural medicines.

9.
J Sep Sci ; 44(11): 2279-2289, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33793077

RESUMO

We proposed a method for the extraction of medicinal herbs, called ultrasound-assisted centrifugal extraction, and an online solvent concentration method. These techniques were coupled with two countercurrent chromatography systems and applied to the continuous extraction and online isolation of chemical constituents from Inonotus obliquus. Raw plants were extracted using a two-phase petroleum-ethanol-water (2.0:1.0:2.0, v/v/v) process, and then the aqueous and organic phases were concentrated using the proposed online solvent concentrator. The countercurrent chromatography preparation prior to separation includes pumping of the two-phase solution, rotating column, and equilibrium column. Following online concentration, the extracted solution was pumped into a second countercurrent chromatography process for separation. During separation, the extraction solution and concentrated extract were prepared automatically. Upon completion of the first cycle of ultrasound-assisted centrifugal extraction/two countercurrent chromatography, the second cycle experiment starts. This process can be indefinitely repeated. In this study, six target compounds with purities above 97.71% were successfully extracted and isolated online using a two-phase solvent system consisting of n-hexane-ethyl acetate-acetonitrile (4.5:1.5:5.5, v/v/v) and n-hexane-ethyl acetate-methanol-water (0.4:3.0:1.5:2.5, v/v/v/v). Compared to conventional extraction methods, the instrumental setup of the proposed method provides enhanced automation, efficiency, purity, and systematic extraction and isolation of natural products.


Assuntos
Inonotus/química , Compostos Fitoquímicos/isolamento & purificação , Ondas Ultrassônicas , Distribuição Contracorrente , Compostos Fitoquímicos/química
10.
Molecules ; 26(9)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922678

RESUMO

Extracts of the fungus Inonotus obliquus exhibit cytotoxic properties against different cancers; hence, this fungal species has been extensively studied. This study aimed to extract total triterpenoids from Inonotus obliquus using ionic liquids (ILs) and separate potential lactate dehydrogenase (LDH) inhibitors via ultrafiltration (UF)-high-speed countercurrent chromatography (HSCCC). Total triterpenoids from Inonotus obliquus were extracted by performing a single-factor experiment and employing a central composite design via ultrasonic-assisted extraction (UAE) and heat-assisted extraction (HAE). The extract was composed of 1-butyl-3-methylimidazolium bromide as the IL and methanol as the dispersant. Ultrafiltration-liquid chromatography (UF-LC) was used to rapidly scan the LDH inhibitors and betulin and lanosterol were identified as potential inhibitors. To obtain these target compounds, betulin and lanosterol with the purities of 95.9% and 97.8% were isolated from HSCCC within 120 min. Their structures were identified using several techniques, among which IL-HAE was fast and effective. This study reports the extraction of triterpenoids from Inonotus obliquus by IL for the first time. Collectively, the findings demonstrate that UF-LC is an effective tool for screening potential LDH inhibitors from crude extracts of I. obliquus and may help to identify bioactive substances against myocardial infarction, whereas high-purity compounds can be separated via UF-HSCCC.


Assuntos
Distribuição Contracorrente/métodos , Inonotus/química , Líquidos Iônicos/química , Triterpenos/química , Ultrafiltração/métodos , Cromatografia Líquida , L-Lactato Desidrogenase/metabolismo
11.
Molecules ; 26(8)2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923444

RESUMO

PACRG (Parkin co-regulated gene) shares a bi-directional promoter with the Parkinson's disease-associated gene Parkin, but the physiological roles of PACRG have not yet been fully elucidated. Recombinant expression methods are indispensable for protein structural and functional studies. In this study, the coding region of PACRG was cloned to a conventional vector pQE80L, as well as two cold-shock vectors pCold II and pCold-GST, respectively. The constructs were transformed into Escherichia coli (DE3), and the target proteins were overexpressed. The results showed that the cold-shock vectors are more suitable for PACRG expression. The soluble recombinant proteins were purified with Ni2+ chelating column, glutathione S-transferase (GST) affinity chromatography and gel filtration. His6 pull down assay and LC-MS/MS were carried out for identification of PACRG-binding proteins in HEK293T cell lysates, and a total number of 74 proteins were identified as potential interaction partners of PACRG. GO (Gene ontology) enrichment analysis (FunRich) of the 74 proteins revealed multiple molecular functions and biological processes. The highest proportion of the 74 proteins functioned as transcription regulator and transcription factor activity, suggesting that PACRG may play important roles in regulation of gene transcription.


Assuntos
Glutationa Transferase/metabolismo , Cromatografia de Afinidade , Cromatografia em Gel , Glutationa Transferase/isolamento & purificação , Células HEK293 , Humanos , Proteínas dos Microfilamentos/isolamento & purificação , Proteínas dos Microfilamentos/metabolismo , Chaperonas Moleculares/isolamento & purificação , Chaperonas Moleculares/metabolismo , Ligação Proteica , Espectrometria de Massas em Tandem , Ubiquitina-Proteína Ligases/metabolismo
12.
Virol J ; 18(1): 81, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33879205

RESUMO

BACKGROUND: Autographa californica multiple nucleopolyhedrovirus (AcMNPV) vp39 is conserved in all sequenced baculovirus genomes. In previous studies, VP39 has been identified as the major capsid structure protein of baculoviruses and found to be essential for nucleocapsid assembly. The nucleocapsid composition and structure of Group I and II NPVs of the Alphabaculovirus genus are very similar. It is not clear whether the major capsid structure protein VP39 of Group I NPVs is functionally identical to or substitutable with the Group II NPV VP39. In this study, the function of Group II Spodoptera litura MNPV (SpltMNPV) VP39 in Group I AcMNPV was characterized. METHODS: Sequence alignment of AcMNPV VP39 and SpltMNPV VP39 was performed using Clustal X and edited with GeneDoc. To determine whether VP39 of Group I NPVs can be functionally substituted by Group II NPV VP39, a vp39-null AcMNPV (vAcvp39KO) and a vp39-pseudotyped AcMNPV (vAcSpltvp39:FLAG), in which the Group I AcMNPV vp39 coding sequence was replaced with that of SpltMNPV from Group II NPVs, were constructed via homologous recombination in Escherichia coli. Using an anti-FLAG monoclonal antibody, immunoblot analysis was performed to examine SpltMNPV VP39 expression. Fluorescence and light microscopy were used to monitor viral replication and infection. Viral growth curve analysis was performed using a fifty percent tissue culture infective dose (TCID50) endpoint dilution assay. Viral morphogenesis was detected using an electron microscope. RESULTS: Sequence alignment indicated that the N-termini of AcMNPV VP39 and SpltMNPV VP39 are relatively conserved, whereas the C-terminus of SpltMNPV VP39 lacks the domain of amino acid residues 306-334 homologous to AcMNPV VP39. Immunoblot analysis showed that SpltMNPV VP39 was expressed in vAcSpltvp39:FLAG. Fluorescence and light microscopy showed that vAcSpltvp39:FLAG did not spread by infection. Viral growth curve analysis confirmed a defect in infectious budded virion production. Electron microscopy revealed that although masses of abnormally elongated empty capsid structures existed inside the nuclei of Sf9 cells transfected with vAcSpltvp39:FLAG, no nucleocapsids were observed. CONCLUSION: Altogether, our results demonstrated that VP39 from SpltMNPV cannot efficiently substitute AcMNPV VP39 during nucleocapsid assembly in AcMNPV.

13.
J Oral Maxillofac Surg ; 79(9): 1954-1962, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33901452

RESUMO

PURPOSE: Microvascular free tissue transfer has become a mainstay for head and neck reconstruction, and vascular anastomosis is 1 of the most challenging aspects. This study aimed to explore a safe, convenient, and efficient technique for end-to-side venous anastomosis using the coupling device. MATERIALS AND METHODS: We evaluated a novel surgical strategy, double thread suspension (DTS), by reviewing data collected in a consecutive series of 60 patients who underwent free tissue grafting after surgical resection of head and neck tumors. Patients who underwent end-to-side microvascular anastomosis using the microvascular coupler device were randomly divided into the DTS group (n = 30) and the traditional procedure group (TRA, n = 30), the demographic data, coupler size, anastomosis time, microvascular complications, and flap survival were determined. RESULTS: The optional size range of coupler devices in the DTS group is better than that of the conventional group, ranging from 1.5 to 4.0 mm compared with 2.0 to 4.0 mm. The average anastomosis time was 4.68 ± 0.43 minutes in the DTS group which was significantly lower than the conventional group that was 9.24 ± 1.46 minutes (P < .0001) . There was no statistically significant difference between the 2 groups in coupler related complications or flap survival. CONCLUSION: The novel DTS technique provides the advantages of lowering procedure complexity, reducing operative time, and preventing tearing of vessel wall, therefore making DTS-guided end-to-side anastomosis a safe, relatively straightforward, and reliable technique.


Assuntos
Retalhos de Tecido Biológico , Procedimentos Cirúrgicos Reconstrutivos , Anastomose Cirúrgica , Cabeça , Humanos , Microcirurgia , Pescoço/cirurgia , Estudos Retrospectivos , Software , Veias/cirurgia
14.
Artigo em Inglês | MEDLINE | ID: mdl-33752055

RESUMO

Herein, ultrasound-assisted mixture extraction (UAME) and online extraction solution concentration (OESC) were conducted to extract products from crops and plants. These techniques were coupled with parallel countercurrent chromatography (PCCC) and applied for continuous extraction and online isolation of chemical constituents from Phellinus vaninii. The UAME instrument comprises extraction and solution separation chambers. It provides higher extraction efficiency and fewer impurities and is suitable for processing various sample matrices. The OESC device comprises a spray nozzle, concentrating cylinder, and hot-blast air nozzle. The mechanical parameters for UAME and OESC were optimized, and the operation of online UAME and OESC coupled with PCCC was described. Raw plant materials were extracted using a two-phase extractant comprising petroleum-ethyl acetate-ethanol-water (0.5:2.0:0.5:2.0, v/v/v/v). The aqueous and organic phases were then concentrated using the OESC technique. Two CCC runs were conducted for preparatory work. After extraction and online concentration, the concentrate was pumped into the CCC for separation. During PCCC separation, continuous automated extraction and concentration were still conducted. When the first cycle of the UAME/OESC/PCCC was completed, followed by the initiation of the second cycle, and the process was continued. Six target compounds with purities exceeding 97.22% were successfully separated using the CCC solvent systems comprising n-hexane-ethyl acetate-acetonitrile-water (5.5:2.5:5.0:0.4, v/v/v/v) and n-butanol-ethanol-water (4.5:1.3:6.5, v/v/v). Compared with conventional extraction methods, the proposed UAME/OESC/PCCC method has higher efficiency, facilitates high-purity separation of analytes, and offers opportunity for automation and systematic preparation of natural products.


Assuntos
Distribuição Contracorrente/métodos , Phellinus/química , Compostos Fitoquímicos/isolamento & purificação , Sonicação/métodos , Automação Laboratorial , Fracionamento Químico , Distribuição Contracorrente/instrumentação , Desenho de Equipamento , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/química , Extratos Vegetais/química , Sonicação/instrumentação
15.
Anal Methods ; 13(7): 918-924, 2021 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-33511974

RESUMO

Inonotus obliquus is a rare medicinal fungus that contains several potential therapeutic ingredients. In this study, the α-glucosidase inhibitory activity of I. obliquus was examined, and a potential α-glucosidase inhibitor, (E)-4-(3,4-dihydroxyphenyl)but-3-en-2-one, was isolated from the I. obliquus extract through ultrafiltration-liquid chromatography (UF-LC). Consecutive high-speed countercurrent chromatography (HSCCC) was used for separation to obtain large quantities of the target compound. The universal quasi-chemical functional group activity coefficient (UNIFAC) model was utilized to prepare a two-phase solvent system, n-hexane/ethyl acetate/ethanol/water (4 : 4.5 : 3.5 : 5, v/v/v/v), wherein the proportions of n-hexane/ethyl acetate/ethanol/water in the stationary and mobile phases were 19.8 : 19.7 : 7.9 : 2.2 (v/v/v/v) and 1 : 16.4 : 57.5 : 136.6 (v/v/v/v), respectively. A flow rate of 2.5 mL min-1 and a column speed of 860 rpm were maintained. Consequently, 10.3 mg of the target compound (95.9% purity) was obtained from 900 mg (6 × 150 mg) of the I. obliquus extract. The use of the UNIFAC model, in combination with consecutive HSCCC separations, allows the purification of large quantities of samples over a short time. Furthermore, the volume of the organic solvent required is reduced. Thus, UF-LC is an effective technique for screening potential α-glucosidase inhibitors isolated from I. obliquus. This can ultimately aid in the discovery of bioactive compounds for the prevention and treatment of diabetes.


Assuntos
Distribuição Contracorrente , Inibidores de Glicosídeo Hidrolases , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Inibidores de Glicosídeo Hidrolases/farmacologia , Inonotus , Extratos Vegetais , Ultrafiltração
16.
J Asian Nat Prod Res ; : 1-8, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33502248

RESUMO

Two new phenolic glycosides (1-2) and eleven known compounds (3-13) were isolated from the fruits of Illicium verum Hook.f. using silica-gel column and preparative middle pressure liquid chromatography (MPLC). The structures of the compounds were elucidated by NMR spectroscopic data. Among them, compounds 3, 5, and 10 were isolated from the family Magnoliaceae for the first time. Additionally, all the compounds were evaluated for their anti-complementary activities against the classical pathway (CP) and the alternative pathway (AP).

17.
J Sep Sci ; 44(7): 1371-1382, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33433962

RESUMO

We present a simple and efficient method based on ultrafiltration high-performance liquid chromatography coupled with a photodiode array detector and electrospray ionization mass spectrometry for the rapid screening and identification of ligands obtainable from the extract of Scutellaria baicalensis. Five major compounds (chrysin-6-C-arabinosyl-8-C-glucoside, chrysin-6-C-glucosyl-8-C-arabinoside, baicalin, oroxylin A-7-O-glucuronide, and wogonoside) were identified as potentially effective inhibitors of lipoxidase and superoxide dismutase. Subsequently, specific binding ligands were separated by high-speed countercurrent chromatography, using ethyl acetate/ethyl alcohol/water acetate (0.1%) (1.0:0.1:1.0, v/v/v) as the solvent system. To the best of our knowledge, this is the first report of S. baicalensis extracts containing potent lipoxidase and superoxide dismutase inhibitors. Our results demonstrate that the systematic isolation of bioactive components from the n-butyl alcohol layer of S. baicalensis guided by ultrafiltration high-performance liquid chromatography coupled with photodiode array detection and electrospray ionization mass spectrometry represents a feasible and efficient technique that could also be employed for the identification and isolation of other enzyme inhibitors.


Assuntos
Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Lipoxigenase/metabolismo , Scutellaria baicalensis/química , Superóxido Dismutase/antagonistas & inibidores , Cromatografia Líquida de Alta Pressão , Distribuição Contracorrente , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Flavonoides/química , Flavonoides/isolamento & purificação , Humanos , Espectrometria de Massas , Estrutura Molecular , Superóxido Dismutase/metabolismo
18.
Phytochem Anal ; 32(3): 382-394, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32893385

RESUMO

INTRODUCTION: Medicago sativa contains flavonoids, saponins, coumarins, sterols, monoterpenes, and organic acids, with flavonoids being the main active constituents. Flavonoids naturally contain a 2-phenylchromone structure with antioxidant, free radical scavenging, cardiovascular, and trace estrogen-like effects. OBJECTIVE: Screening and isolation of neuraminidase, lipoxidase, and lactate dehydrogenase inhibitors from M. sativa via ultrafiltration-liquid chromatography-mass spectrometry (UF-LC-MS) combined with stepwise flow rate counter-current chromatography (CCC). METHOD: Utilising the medicinal plants M. sativa as the research objects and UF-LC-MS was used for activity screening followed by isolation and purification of the inhibitors by stepwise flow rate CCC. Finally, identification of the three active compounds was achieved by MS and nuclear magnetic resonance. RESULTS: Three major compounds, viz. quercetin, genistein, and formononetin, were identified as potent neuraminidase, lipoxidase, and lactate dehydrogenase inhibitors, respectively. A two-phase solvent system of ethyl acetate/methanol/n-butanol/water (5.0:1.5:5.0:10; v/v/v/v) was subsequently selected for separation by stepwise flow rate CCC. CONCLUSION: This novel approach based on UF-LC-MS and stepwise flow rate CCC represents a powerful tool for the screening and isolation of neuraminidase, lipoxidase, and lactate dehydrogenase inhibitors from complex matrices. Therefore, a useful platform for the large-scale production of bioactive and nutraceutical ingredients was developed herein.


Assuntos
Distribuição Contracorrente , Ultrafiltração , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Medicago sativa , Extratos Vegetais
19.
Neoplasma ; 68(1): 31-39, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32940042

RESUMO

The failure to treat and control the growth of metastases is the main cause of death in breast cancer (BC) patients. Compared to the traditional method of analyzing circulating tumor DNA (ctDNA), capturing intact circulating tumor cells (CTCs) allows us to more accurately characterize mutations and identify suitable targeted therapies. We used CellCollector to collect peripheral CTCs. Thirty metastatic breast cancer (MBC) patients were enrolled, and 17 were analyzed with next-generation sequencing (NGS) methods. Clinical characteristics were analyzed along with the CTCs enumeration and detection rates. Whole-genome amplification (WGA) was used to amplify the CTC genomic DNA of 127 genes. Patients younger than 45 years old, with brain metastasis, with three or more metastatic sites, or with HER2-positive had the highest number of CTCs collected. The CTCs detection rate was also correlated to the number of metastasis sites. Different metastasis sites such as the brain, viscus, bone, and soft tissue contained specific high-frequency gene mutations. AKT3, MYC, and NT5C2 mutations were only found in brain metastases. APC, BCL2L11, ESRP1, FLT3 mutations were only in the visceral metastases. KEAP1, KIT, MET were the specific mutation genes in patients with bone and soft tissue metastases. These findings provide evidence that we can detect gene mutation information for obtaining the biological characteristics by CTCs using CellCollector. Different metastasis sites contain specific high-frequency mutation genes, which provide guidance to the accurate gene therapy.


Assuntos
Neoplasias da Mama , Mutação , Células Neoplásicas Circulantes , Biomarcadores Tumorais/genética , Neoplasias da Mama/sangue , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica
20.
Nat Prod Res ; 35(8): 1331-1339, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31385536

RESUMO

Two new flavonoids, (2S)-6,8-dimethyl-5,7,3',4'-tetrahydroxyflavanone 4'-O-ß-D-glucopyranoside (1) and quercetin 3-O-ß-D-(6''-p-methoxybenzoyl)-galactopyranoside (2), together with ten known flavonoids (3-12) were isolated from the leaves of Rhododendron dauricum L. The structures of the flavonoids were characterized from spectroscopic data (1D and 2D NMR and HR-ESI-MS). The isolated flavonoids were evaluated for their inhibitory effects on the production of tumour necrosis factor (TNF)-α in LPS-stimulated RAW 264.7 cells. Compound 11 exhibited inhibitory activity against TNF-α production with an IC50 value of 46.2 ± 1.2 µM.


Assuntos
Flavonoides/isolamento & purificação , Lipopolissacarídeos/farmacologia , Folhas de Planta/química , Rhododendron/química , Fator de Necrose Tumoral alfa/biossíntese , Animais , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Flavonoides/química , Camundongos , Extratos Vegetais/química , Quercetina/análise , Células RAW 264.7 , Rhododendron/efeitos dos fármacos
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