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1.
Crit Rev Food Sci Nutr ; : 1-22, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38889067

RESUMO

Innovating food additives stands as a cornerstone for the sustainable evolution of future food systems. Peptides derived from food proteins exhibit a rich array of physicochemical and biological attributes crucial for preserving the appearance, flavor, texture, and nutritional integrity of foods. Leveraging these peptides as raw materials holds great promise for the development of novel food additives. While numerous studies underscore the potential of peptides as food additives, existing reviews predominantly focus on their biotic applications, leaving a notable gap in the discourse around their abiotic functionalities, such as their physicochemical properties. Addressing this gap, this review offers a comprehensive survey of peptide-derived food additives in food systems, accentuating the application of peptides' abiotic properties. It furnishes a thorough exploration of the underlying mechanisms and diverse applications of peptide-derived food additives, while also delineating the challenges encountered and prospects for future applications. This well-time review will set the stage for a deeper understanding of peptide-derived food additives.

2.
Zhongguo Zhong Yao Za Zhi ; 49(5): 1249-1254, 2024 Mar.
Artigo em Zh | MEDLINE | ID: mdl-38621971

RESUMO

The chemical constituents of Draconis Sanguis were preliminarily studied by macroporous resin, silica gel, dextran gel, and high-performance liquid chromatography. One retro-dihydrochalcone, four flavonoids, and one stilbene were isolated. Their chemical structures were identified as 4-hydroxy-2,6-dimethoxy-3-methyldihydrochalcone(1), 4'-hydroxy-5,7-dimethoxy-8-methylflavan(2), 7-hydroxy-4',5-dimethoxyflavan(3),(2S)-7-hydroxy-5-methoxy-6-methylflavan(4),(2S)-7-hydroxy-5-methoxyflavan(5), and pterostilbene(6) by modern spectroscopy, physicochemical properties, and literature comparison. Compound 1 was a new compound. Compounds 2 and 6 were first found in the Arecaceae family. Compound 5 had the potential to prevent and treat diabetic kidney disease.


Assuntos
Arecaceae , Diabetes Mellitus , Nefropatias Diabéticas , Medicamentos de Ervas Chinesas , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/prevenção & controle , Flavonoides/análise , Medicamentos de Ervas Chinesas/química , Cromatografia Líquida de Alta Pressão/métodos
3.
World J Microbiol Biotechnol ; 38(5): 75, 2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35298707

RESUMO

γ-aminobutyric acid (GABA) has various physiological functions and is widely used in medicine, food, and other fields. Glutamate decarboxylase (GAD) is a key enzyme that catalyzes the decarboxylation of L-glutamate to synthesize GABA. However, the industrial application of microorganism-derived GAD is limited by its rapid loss of enzymatic activity with pH approaching neutrality. In this study, a novel glutamate decarboxylase, GADMSM, from Mycobacterium smegmatis was overexpressed and purified. On the basis of homologous modeling and substrate molecular docking, several GADMSM mutants were constructed, and their enzymatic properties were analyzed. The results showed that the optimal pH of wild-type GADMSM is 5.4; at pH 6.2, 22.8% enzymatic activity was retained. The T211I replacement in GAD and C-terminal deletion mutant GADMSMΔC showed relatively high catalytic activity in a pH range of 5.0-7.0. The Vmax and Km values of GADMSMΔC were 14.69 and 5.70, respectively, at pH 5.5, and 9.87 and 6.17, respectively, at pH 7.0. Compared with the wild-type GAD, GADMSMΔC maintained higher affinity and enzymatic activity of the substrate, maintaining 78.5% of the highest enzymatic activity even at pH 7.0, which is the highest reported activity retention for GAD under neutral pH condition. Therefore, GADMSMΔC can be used for the transformation of high-yielding strains and industrial production of GABA.


Assuntos
Glutamato Descarboxilase , Mycobacterium smegmatis , Glutamato Descarboxilase/química , Glutamato Descarboxilase/genética , Concentração de Íons de Hidrogênio , Simulação de Acoplamento Molecular , Mutagênese , Mycobacterium smegmatis/genética
4.
Zhongguo Zhong Yao Za Zhi ; 47(17): 4715-4722, 2022 Sep.
Artigo em Zh | MEDLINE | ID: mdl-36164879

RESUMO

This study aims to investigate the therapeutic effects of alkaloids in Tibetan medicine Bangna(Aconiti Penduli et Aconiti Flavi Radix) on osteoarthritis(OA) rats in vitro and in vivo and the underlying mechanisms. Chondrocytes were isolated from 2-3 week-old male SD rats and lipopolysaccharide(LPS) was used to induce OA in chondrocytes in vitro. Methyl thiazolyl tetrazolium(MTT) assay was used to investigate the toxicity of seven alkaloids(12-epi-napelline, songorine, benzoylaconine, aconitine, 3-acetylaconitine, mesaconitine, and benzoylmesaconine) to chondrocytes. Chondrocytes were classified into the control group, model group(induced by LPS 5 µg·mL~(-1) for 12 h), and administration groups(induced by LPS 5 µg·mL~(-1) for 12 h and incubated for 24 h). The protein expression of inflammatory factors cyclooxygenase-2(COX-2), inducible nitric oxide synthetase(iNOS), tumor necrosis factor-α(TNF-α), and interleukin-1ß(IL-1ß) in each group were detected by Western blot, and the protein expression of matrix metalloprotease-13(MMP-13), aggrecan, collagen Ⅱ, fibroblast growth factor 2(FGF2) by immunofluorescence staining. For the in vivo experiment, sodium iodoacetate was used to induce OA in rats, and the expression of MMP-13, TNF-α, and FGF2 in cartilage tissues of rats in each group was detected by immunohistochemistry. The results showed that the viability of chondrocytes could reach more than 90% under the treatment of the seven alkaloids in a certain dose range. Aconitine, 12-epi-napelline, songorine, 3-acetylaconitine, and mesaconitine could decrease the protein expression of inflammatory factors COX-2, iNOS, TNF-α and IL-1ß compared with the model group. Moreover, 12-epi-napelline, aconitine, and mesaconitine could down-regulate the expression of MMP-13 and up-regulate the expression of aggrecan and collagen Ⅱ. In addition, compared with the model group and other Bangna alkaloids, 12-epi-napelline significantly up-regulated the expression of FGF2. Therefore, 12-epi-napelline was selected for the animal experiment in vivo. Immunohistochemistry results showed that 12-epi-napelline could significantly reduce the expression of MMP-13 and TNF-α in cartilage tissues, and up-regulate the expression of FGF2 compared with the model group. In conclusion, among the seven Bangna alkaloids, 12-epi-napelline can promote the repair of OA in rats by down-regulating the expression of MMP-13 and TNF-α and up-regulating the expression of FGF2.


Assuntos
Aconitina , Aconitum , Alcaloides , Medicina Tradicional Tibetana , Osteoartrite , Aconitina/análogos & derivados , Aconitina/uso terapêutico , Aconitum/química , Agrecanas/metabolismo , Alcaloides/uso terapêutico , Animais , Células Cultivadas , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/uso terapêutico , Interleucina-1beta/metabolismo , Ácido Iodoacético/uso terapêutico , Lipopolissacarídeos , Masculino , Metaloproteinase 13 da Matriz/metabolismo , NF-kappa B/metabolismo , Osteoartrite/tratamento farmacológico , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
5.
Soft Matter ; 17(17): 4496-4503, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33949603

RESUMO

We report a mechanical metamaterial-like behavior as a function of the micro/nanostructure of otherwise chemically identical aliphatic polyurea aerogels. Transmissibility varies dramatically with frequency in these aerogels. Broadband vibration mitigation is provided at low frequencies (500-1000 Hz) through self-assembly of locally resonant metastructures wherein polyurea microspheres are embedded in a polyurea web-like network. A micromechanical constitutive model based on a discrete element method is established to explain the vibration mitigation mechanism. Simulations confirm the metamaterial-like behavior with a negative dynamic material stiffness for the micro-metastructured aerogels in a much wider frequency range than the majority of previously reported locally resonant metamaterials.

6.
Chem Biodivers ; 15(11): e1800289, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30194898

RESUMO

A number of podophyllotoxin derivatives (3A-3J) had been designed and synthesized, and their biological activities were evaluated in this study. Moreover, the antiproliferation activities of these compounds against four human cancer cell lines (HepG2, HeLa, A549, and MCF-7) were also tested. The results indicated that the most promising compound 3D displayed potent inhibitory activity over the four human cancer cell lines and was further demonstrated to have potent tubulin polymerization inhibitory effects without damaging the non-cancer cells. Additionally, 3D was verified to effectively interfere with tubulin and could prevent the mitosis of cancer cells, leading to cell cycle arrest and eventually inducing apoptosis in a dose- and time-dependent manner. Moreover, the Western blotting and siRNA results showed that Bcl-2 was downregulated in HepG2 cells treated with 3D. Finally, the molecular docking simulation results revealed that 3D could fit well in the colchicine-binding pocket. Taken together, this study has provided certain novel antitubulin agents for possible cancer chemotherapy.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Podofilotoxina/farmacologia , Tubulina (Proteína)/metabolismo , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Conformação Molecular , Simulação de Acoplamento Molecular , Podofilotoxina/síntese química , Podofilotoxina/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
7.
Zhongguo Zhong Yao Za Zhi ; 42(7): 1395-1400, 2017 Apr.
Artigo em Zh | MEDLINE | ID: mdl-29052405

RESUMO

Artemisia hedinii occupies an important position in the Tibetan medicine. Plants in Artemisia vary a lot and are widely distributed in the Qinghai-Tibet Plateau, many plants in Artemisia look similar, making traditional identification methods laborious. In this article, ITS2 sequences were used as DNA barcoding to identify four kinds of confusable Tibetan medicine plants in Artemisia, aiming to establish a rapid and accurate identification methods. Twenty-one samples in Artemisia were collected from the Qinghai-Tibet Plateau, ITS2 sequence PCR amplification and sequencing were conducted after the extraction of DNA. Another 11 sequence downloaded from Genbank were added to the analysis. Genetic distance calculation and analysis, building Neighbor Joining (NJ) phylogenetic tree were conducted by MEGA 6.0, also comparison of secondary structures of ITS2 sequences among samples. A. hedinii, A. annua, A. dubia and A. argyi shared close genetic distance, but the maximum distance between the four species was much greater than the minimum distance within each species, NJ tree showed that the four species went to four separate branches, differences among secondary structures of ITS2 sequences also made it clear to identify these medical plants. It could be an accurate and rapid method for identification and recognition, as well as the evolutionary relationships between the species by using ITS2 sequence as DNA barcode for plants of Tibetan Artemisia. The study provides theoretical basis for quality control, medication safety and rational exploitation.


Assuntos
Artemisia/genética , Código de Barras de DNA Taxonômico , DNA Espaçador Ribossômico/genética , Filogenia , DNA de Plantas/genética , Plantas Medicinais/genética , Tibet
8.
Amino Acids ; 48(11): 2657-2670, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27487778

RESUMO

Natural and nutrient substances for cardiovascular disease are promising and capture researchers' minds. Two kinds of novel bioactive peptides (high Fischer's ratio oligopeptides and anticoagulant peptides) were obtained from Whitmania pigra protein via enzymatic hydrolysis. An oligopeptide (MW<874.0 Da) named as HF2 was obtained via chromatography purification procedures with a high Fischer's ratio of 31.92 ± 1.36 and low phenylalanine + tyrosine content of 0.98 ± 0.04 %. Another peptide (WA3-1), prepared by alcalase AF 2.4 L-catalyzed hydrolysis and then purified by DEAE Sepharose FF, gel Sephadex G-15 chromatography, exhibited high anticoagulant activity with prolonging significantly plasma clotting time on activated partial thromboplastin time, prothrombin time, thrombin time (p < 0.01) and powerful thrombolytic activity. Amino acid composition and MALDI-TOF/TOF MS analysis showed that WA3-1 contained 11 amino acids (MW: 1422.0 Da) with the sequence as NH2-His-Asp-Phe-Leu-Asn-Asn-Lys-Leu-Glu-Tyr-Glu-COOH. Abundant negatively charged amino acids in C-terminal, as well as the special residue Lys contribute to its anticoagulant capacity. This research provided a novel natural candidate for the manufacture of nutrient oligopeptides with high branched chain amino acid, and anticoagulant thrombolytic agent in pharmaceutical industry with helping prevent from thrombosis and related cardiovascular diseases.


Assuntos
Sequência de Aminoácidos , Anticoagulantes , Coagulação Sanguínea/efeitos dos fármacos , Sanguessugas/química , Oligopeptídeos , Terapia Trombolítica , Aminoácidos de Cadeia Ramificada , Animais , Anticoagulantes/química , Anticoagulantes/isolamento & purificação , Anticoagulantes/farmacologia , Humanos , Oligopeptídeos/química , Oligopeptídeos/genética , Oligopeptídeos/isolamento & purificação , Oligopeptídeos/farmacologia
9.
Appl Opt ; 55(8): 2018-23, 2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26974797

RESUMO

A novel and simple technique based on the light diffraction effect for visualization of low-frequency underwater acoustic waves (LFUAWs) in real time has been developed in this paper. A cylindrical object has been put on the surface of the water. A low-frequency underwater longitudinal wave can be generated into a water surface transversal capillary wave around the cylinder by our technique. Modulating the phase of a laser beam reflected from a water surface by surface acoustic waves (SAWs) realizes the acousto-optic effect. Then, a steady and visible diffraction pattern is experimentally observed. A physical model of the SAW is established to verify the feasibility of our technique. An analytical expression of wavelength, wave amplitude, and excitation frequency has been derived to study the physical properties of LFUAWs, and it explains the experimental phenomenon very well. As a result, the technique is effective, easy, and practical for visualizing LFUAWs and has significance for applications.

10.
Zhongguo Zhong Yao Za Zhi ; 40(13): 2674-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26697698

RESUMO

The study focused on the therapeutic efficacy of Tibetan medicines on cerebral ischemia. The combined medication methods and administration habits in clinic for more than 10 years were simulated. Three typical Tibetan medicines, i.e., 25-Herb Shanhu pill, Wishful-Treasure pill and 20-Herb Chenxiang pill, were administered to the animal model of permanent middle cerebral artery occlusion in the morning, noon and evening, respectively. On the second day after the final administration, the activity of serum oxidative stress marker SOD and the content of MDA were evaluated. Infarct volumes were quantified through TTC staining. Inflammatory reaction maker NF-kappaB p65 gene and apoptosis. makers Bax and Cyct were selected to study the molecular mechanism of combined herbs with the immunohistochemistry technique. According to the result, the respective combination of 25-Herb Shanhu pill, Wishful-Treasure pill and 20-Herb Chenxiang pill in the morning, noon and evening showed unique advantages in reducing the damage of oxidative stress, infarct volumes, encephaledema caused by ischemia, inflammatory factor aggregation and inhibiting apoptosis, with consistent therapeutic efficacies in clinic.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Medicina Tradicional Tibetana , Animais , Isquemia Encefálica/metabolismo , Peroxidação de Lipídeos , Masculino , Ratos , Superóxido Dismutase/metabolismo , Fatores de Tempo , Fator de Transcrição RelA/fisiologia
11.
Zhongguo Zhong Yao Za Zhi ; 40(8): 1453-8, 2015 Apr.
Artigo em Zh | MEDLINE | ID: mdl-26281578

RESUMO

The study is aimed to ensure the quality and safety of medicinal plants by using ITS2 DNA barcode technology to identify Corydalis boweri, Meconopsis horridula and their close related species. The DNA of 13 herb samples including C. boweri and M. horridula from Lhasa of Tibet was extracted, ITS PCR were amplified and sequenced. Both assembled and web downloaded 71 ITS2 sequences were removed of 5. 8S and 28S. Multiple sequence alignment was completed and the intraspecific and interspecific genetic distances were calculated by MEGA 5.0, while the neighbor-joining phylogenetic trees were constructed. We also predicted the ITS2 secondary structure of C. boweri, M. horridula and their close related species. The results showed that ITS2 as DNA barcode was able to identify C. boweri, M. horridula as well as well as their close related species effectively. The established based on ITS2 barcode method provides the regular and safe detection technology for identification of C. boweri, M. horridula and their close related species, adulterants and counterfeits, in order to ensure their quality control, safe medication, reasonable development and utilization.


Assuntos
Corydalis/classificação , Código de Barras de DNA Taxonômico/métodos , DNA de Plantas/genética , DNA Espaçador Ribossômico/genética , Papaveraceae/classificação , Sequência de Bases , China , Corydalis/química , Corydalis/genética , DNA de Plantas/química , DNA Espaçador Ribossômico/química , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Papaveraceae/química , Papaveraceae/genética , Filogenia , Plantas Medicinais/química , Plantas Medicinais/classificação , Plantas Medicinais/genética
12.
Biochem Biophys Res Commun ; 452(4): 888-94, 2014 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-25181341

RESUMO

The hydrolysate from duck egg white protein (DEWP) prepared by "SEEP-Alcalase" at degree of hydrolysis (DH) value of 21% (namely HSA21) exhibited high antioxidant capacity in different oxidation systems. A consecutive chromatographic method was then developed for separation and purification of HSA21, including ion-exchange chromatography, macroporous adsorption resin (MAR) and gel filter chromatography. The final peptides "P21-3-75-B" were obtained with significantly enhanced antioxidant activity (p<0.05). It was further confirmed that the product mainly consisted of five oligopeptides (Mr: 202.1, 294.1, 382.1, 426.3, and 514.4Da). Furthermore, the antioxidant activity of P21-3-75-B kept stable after in vitro digestive simulation. Antioxidant capacity of the purified peptides was closely related to the molecular mass, hydrophobic amino acid residues, acidic amino acid and some antioxidant amino acids. This research provided a valuable route for producing new natural-source peptides with strong antioxidant capacity and high nutritious value for our daily intake.


Assuntos
Antioxidantes/química , Antioxidantes/isolamento & purificação , Patos/metabolismo , Proteínas do Ovo/química , Proteínas do Ovo/isolamento & purificação , Oligopeptídeos/química , Oligopeptídeos/isolamento & purificação , Animais , Estabilidade de Medicamentos , Radicais Livres/química , Conteúdo Gastrointestinal/química , Hidrólise , Oxigênio/química , Hidrolisados de Proteína/química , Hidrolisados de Proteína/isolamento & purificação
13.
Biochem Biophys Res Commun ; 454(1): 157-61, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25450373

RESUMO

The Sterile Alpha Motif Domain-containing 9 (SAMD9) gene has been recently emphasized during the discovery that it is expressed at a lower level in aggressive fibromatosis and some cases of breast and colon cancer, however, the underlying mechanisms are poorly understood. Here, we found that SAMD9 is down-regulated in human non-small cell lung cancer (NSCLC). Furthermore, knockdown of SAMD9 expression is increased the invasion, migration and proliferation in H1299 cells in vitro and overexpression of SAMD9 suppressed proliferation and invasion in A549 cells. Finally, depletion of SAMD9 increases tumor formation in vivo. Our results may provide a strategy for blocking NSCLC tumorigenesis and progression.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/genética , Proteínas/genética , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/etiologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Progressão da Doença , Regulação para Baixo , Técnicas de Silenciamento de Genes , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/patologia , Invasividade Neoplásica , Proteínas/antagonistas & inibidores , Proteínas/metabolismo , Regulação para Cima
14.
Genome ; 57(6): 345-53, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25264805

RESUMO

Gordonia neofelifaecis NRRL B-59395 was initially isolated from the fresh feces of a clouded leopard based on its ability to degrade cholesterol. The transcriptome profiles of G. neofelifaecis NRRL B-59395 grown with cholesterol, androstenedione (AD), and pyruvic acid were compared by RNA-Seq. The sterol catabolic genes are highly conserved in G. neofelifaecis, Rhodococcus jostii RHA1, and Mycobacterium tuberculosis. The RNA-Seq results indicated that the genes involved in the sterol side chain cleavage were exclusively induced by cholesterol, while the genes involved in the degradation of rings A/B and C/D were up-regulated by both cholesterol and AD. It appears that the induction mechanisms for the genes responsible for side chain cleavage and those for degradation of rings are different. There are approximately 21 genes encoding transporter proteins that are differentially expressed in cholesterol or AD compared with pyruvic acid. The genes camABCD and camM encode two systems that take up cholate, and they have been shown to be cholesterol- and AD-inducible. The potential biological functions of other differentially expressed genes are also discussed. These results will promote the functional characterization of the sterol catabolic genes and also provide important clues in understanding the mechanisms of their gene expression, and they may help us understand the mechanism underlying microbial cholesterol catabolism.


Assuntos
Bactéria Gordonia/genética , Bactéria Gordonia/metabolismo , Esteroides/metabolismo , Androstenodiona/metabolismo , Androstenodiona/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Colesterol/metabolismo , Colesterol/farmacologia , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Bactéria Gordonia/crescimento & desenvolvimento , Óperon , Ácido Pirúvico/metabolismo , Ácido Pirúvico/farmacologia , Esteroides/farmacologia , Transcriptoma
15.
Microb Cell Fact ; 13: 143, 2014 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-25273324

RESUMO

BACKGROUND: The use of biocatalysts has become an increasingly attractive alternative to traditional chemical methods, due to the high selectivity, mild reaction conditions and environmentally-friendly processes in nonaqueous catalysis of nucleosids. However, the extensive use of organic solvents may generally suffer from sever drawbacks such as volatileness and toxicity to the environment and lower activity of the biocatalyst. Recently, ionic liquids are considered promising solvents for nonaqueous biocatalysis of polyhydroxyl compounds as ILs are environmental-friendly. RESULTS: In this research, we developed new IL-containing reaction systems for synthesis of long chain nucleoside ester catalyzed by Pseudomonas fluorescens whole-cells. Various ILs exerted significant but different effects on the bio-reaction. And their effects were closely related with both the anions and cations of the ILs. Use of 10% [BMI][PF6]/THF gave high reaction efficiency of arabinocytosine laurate synthesis, in which the initial rate, product yield and 5'-regioselectivity reached 2.34 mmol/L·h, 81.1% and >99%, respectively. Furthermore, SEM analysis revealed that ILs can alter the cell surface morphology, improve the permeability of cell envelopes and thus facilitate the mass transfer of substrates to the active sites of cell-bound enzymes. CONCLUSION: Our research demonstrated the potential of ILs as promising reaction medium for achieving highly efficient and regioselective whole-cell catalysis.


Assuntos
Líquidos Iônicos/química , Nucleosídeos/química , Pseudomonas fluorescens/química , Acilação , Catálise , Nucleosídeos/metabolismo , Pseudomonas fluorescens/metabolismo
16.
Front Oncol ; 14: 1343170, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38357195

RESUMO

Purpose: This study aims to develop an optimal machine learning model that uses lung equivalent uniform dose (lung EUD to predict radiation pneumonitis (RP) occurrence in lung cancer patients treated with volumetric modulated arc therapy (VMAT). Methods: We analyzed a cohort of 77 patients diagnosed with locally advanced squamous cell lung cancer (LASCLC) receiving concurrent chemoradiotherapy with VMAT. Patients were categorized based on the onset of grade II or higher radiation pneumonitis (RP 2+). Dose volume histogram data, extracted from the treatment planning system, were used to compute the lung EUD values for both groups using a specialized numerical analysis code. We identified the parameter α, representing the most significant relative difference in lung EUD between the two groups. The predictive potential of variables for RP2+, including physical dose metrics, lung EUD, normal tissue complication probability (NTCP) from the Lyman-Kutcher-Burman (LKB) model, and lung EUD-calibrated NTCP for affected and whole lung, underwent both univariate and multivariate analyses. Relevant variables were then employed as inputs for machine learning models: multiple logistic regression (MLR), support vector machine (SVM), decision tree (DT), and K-nearest neighbor (KNN). Each model's performance was gauged using the area under the curve (AUC), determining the best-performing model. Results: The optimal α-value for lung EUD was 0.3, maximizing the relative lung EUD difference between the RP 2+ and non-RP 2+ groups. A strong correlation coefficient of 0.929 (P< 0.01) was observed between lung EUD (α = 0.3) and physical dose metrics. When examining predictive capabilities, lung EUD-based NTCP for the affected lung (AUC: 0.862) and whole lung (AUC: 0.815) surpassed LKB-based NTCP for the respective lungs. The decision tree (DT) model using lung EUD-based predictors emerged as the superior model, achieving an AUC of 0.98 in both training and validation datasets. Discussions: The likelihood of developing RP 2+ has shown a significant correlation with the advancements in RT technology. From traditional 3-D conformal RT, lung cancer treatment methodologies have transitioned to sophisticated techniques like static IMRT. Accurately deriving such a dose-effect relationship through NTCP modeling of RP incidence is statistically challenging due to the increased number of degrees-of-freedom. To the best of our knowledge, many studies have not clarified the rationale behind setting the α-value to 0.99 or 1, despite the closely aligned calculated lung EUD and lung mean dose MLD. Perfect independence among variables is rarely achievable in real-world scenarios. Four prominent machine learning algorithms were used to devise our prediction models. The inclusion of lung EUD-based factors substantially enhanced their predictive performance for RP 2+. Our results advocate for the decision tree model with lung EUD-based predictors as the optimal prediction tool for VMAT-treated lung cancer patients. Which could replace conventional dosimetric parameters, potentially simplifying complex neural network structures in prediction models.

17.
Comput Biol Med ; 178: 108693, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38850960

RESUMO

AIM: Kaempferitrin is an active component in Chenopodium ambrosioides, showing medicinal functions against liver cancer. This study aimed to identify the potential targets and pathways of kaempferitrin against liver cancer using network pharmacology and molecular docking, and verify the essential hub targets and pathway in mice model of SMMC-7721 cells xenografted tumors and SMMC-7721 cells. METHODS: Kaempferitrin therapeutical targets were obtained by searching SwissTargetPrediction, PharmMapper, STITCH, DrugBank, and TTD databases. Liver cancer specific genes were obtained by searching GeneCards, DrugBank, TTD, OMIM, and DisGeNET databases. PPI network of "kaempferitrin-targets-liver cancer" was constructed to screen the hub targets. GO, KEGG pathway and MCODE clustering analyses were performed to identify possible enrichment of genes with specific biological subjects. Molecular docking and molecular dynamics simulation were employed to determine the docking pose, potential and stability of kaempferitrin with hub targets. The potential anti-liver cancer mechanisms of kaempferitrin, as predicted by network pharmacology analyses, were verified by in vitro and in vivo experiments. RESULTS: 228 kaempferitrin targets and 2186 liver cancer specific targets were identified, of which 50 targets were overlapped. 8 hub targets were identified through network topology analysis, and only SIRT1 and TP53 had a potent binding activity with kaempferitrin as indicated by molecular docking and molecular dynamics simulation. MCODE clustering analysis revealed the most significant functional module of PPI network including SIRT1 and TP53 was mainly related to cell apoptosis. GO and KEGG enrichment analyses suggested that kaempferitrin exerted therapeutic effects on liver cancer possibly by promoting apoptosis via p21/Bcl-2/Caspase 3 signaling pathway, which were confirmed by in vivo and in vitro experiments, such as HE staining of tumor tissues, CCK-8, qRT-PCR and Western blot. CONCLUSION: This study provided not only insight into how kaempferitrin could act against liver cancer by identifying hub targets and their associated signaling pathways, but also experimental evidence for the clinical use of kaempferitrin in liver cancer treatment.

18.
ACS Appl Mater Interfaces ; 15(51): 59329-59336, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38091363

RESUMO

Metallic zinc (Zn) has been considered one of the most promising anode materials for next-generation aqueous Zn batteries due to its low redox potential and high storage capacity. However, excessive dendrite formation in Zn metal, corrosion, the evolution of hydrogen gas during the cycling process, and the poor Zn-ion (Zn2+) transport from the electrolyte to the electrode limit its practical application. One of the most effective strategies to suppress Zn dendrite growth and promote Zn2+ transport is to introduce suitable protective layers between the Zn metal electrode and the electrolyte. Herein, we mathematically simulated the dynamic interactions between the Zn deposition on the anode and the resulting displacement of a protective layer that covers the anode, the latter of which can simultaneously inhibit Zn dendrite growth and enhance the Zn2+ transport through the interface between the Zn anode and the protective layer. Our simulation results indicate that a protective layer of high Zn2+ diffusivity not only improves the deposition rate of the Zn metal but also prevents dendrite growth by homogenizing the Zn2+ concentration at the anode surface. In addition, it is revealed that the anisotropic Zn2+ diffusivity in the protective layer influences the 2D diffusion of Zn2+. Higher Zn2+ diffusivity perpendicular to the Zn metal surface inhibits dendrite growth, while higher diffusivity parallel to the Zn metal surface promotes dendrite growth. Our work thus provides a fundamental understanding and a design principle for controlling anisotropic Zn2+ diffusion in the protective layer for better suppression of dendrite growth in Zn metal batteries.

19.
Chem Commun (Camb) ; 59(22): 3289-3292, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36843398

RESUMO

We report a cyclic organosulfide synthesized via a condensation reaction. It can be cycled for 1000 times in half cells. Impressively, it can work with lithiated carbon paper as the anode in ether electrolyte in a full cell. This work shows the promising property of the organosulfide cathode in lithium batteries.

20.
Biosens Bioelectron ; 228: 115189, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36893718

RESUMO

Pathogenic biosafety is a worldwide concern. Tools for analyzing pathogenic biosafety, that are precise, rapid and field-deployable, are highly demanded. Recently developed biotechnological tools, especially those utilizing CRISPR/Cas systems which can couple with nanotechnologies, have enormous potential to achieve point-of-care (POC) testing for pathogen infection. In this review, we first introduce the working principle of class II CRISPR/Cas system for detecting nucleic acid and non-nucleic acid biomarkers, and highlight the molecular assays that leverage CRISPR technologies for POC detection. We summarize the application of CRISPR tools in detecting pathogens, including pathogenic bacteria, viruses, fungi and parasites and their variants, and highlight the profiling of pathogens' genotypes or phenotypes, such as the viability, and drug-resistance. In addition, we discuss the challenges and opportunities of CRISPR-based biosensors in pathogenic biosafety analysis.


Assuntos
Técnicas Biossensoriais , Contenção de Riscos Biológicos , Bioensaio , Biotecnologia , Sistemas CRISPR-Cas/genética
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