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1.
BMC Bioinformatics ; 21(1): 13, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31924164

RESUMO

BACKGROUND: The rapid growth of available knowledge on metabolic processes across thousands of species continues to expand the possibilities of producing chemicals by combining pathways found in different species. Several computational search algorithms have been developed for automating the identification of possible heterologous pathways; however, these searches may return thousands of pathway results. Although the large number of results are in part due to the large number of possible compounds and reactions, a subset of core reaction modules is repeatedly observed in pathway results across multiple searches, suggesting that some subpaths between common compounds were more consistently explored than others.To reduce the resources spent on searching the same metabolic space, a new meta-algorithm for metabolic pathfinding, Hub Pathway search with Atom Tracking (HPAT), was developed to take advantage of a precomputed network of subpath modules. To investigate the efficacy of this method, we created a table describing a network of common hub metabolites and how they are biochemically connected and only offloaded searches to and from this hub network onto an interactive webserver capable of visualizing the resulting pathways. RESULTS: A test set of nineteen known pathways taken from literature and metabolic databases were used to evaluate if HPAT was capable of identifying known pathways. HPAT found the exact pathway for eleven of the nineteen test cases using a diverse set of precomputed subpaths, whereas a comparable pathfinding search algorithm that does not use precomputed subpaths found only seven of the nineteen test cases. The capability of HPAT to find novel pathways was demonstrated by its ability to identify novel 3-hydroxypropanoate (3-HP) synthesis pathways. As for pathway visualization, the new interactive pathway filters enable a reduction of the number of displayed pathways from hundreds down to less than ten pathways in several test cases, illustrating their utility in reducing the amount of presented information while retaining pathways of interest. CONCLUSIONS: This work presents the first step in incorporating a precomputed subpath network into metabolic pathfinding and demonstrates how this leads to a concise, interactive visualization of pathway results. The modular nature of metabolic pathways is exploited to facilitate efficient discovery of alternate pathways.


Assuntos
Algoritmos , Redes e Vias Metabólicas , Ácido Láctico/análogos & derivados , Ácido Láctico/química , Ácido Láctico/metabolismo , Ácido Pirúvico/metabolismo
2.
Chem Commun (Camb) ; 56(13): 2004-2007, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-31960849

RESUMO

The operation of wearable epidermal biofuel cells is prone to rapid irreversible deactivation effects under dynamic sweat pH changes from neutral to acidic. We demonstrate that the encapsulation of lactate-oxidase (LOx) within a hydrophobic protective carbon-paste anode imparts unusually high stability during dynamically changing pH fluctuations and allows the BFC to continue harvesting the lactate bioenergy even after long exposures to acidic conditions. The unique power-recovery ability of the carbon-paste BFC after its failure in harsh pH is attributed to the protective action of the non-polar paste environment.


Assuntos
Fontes de Energia Bioelétrica , Técnicas Biossensoriais/métodos , Glucose Oxidase/metabolismo , Carbono/química , Eletrodos , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Glucose Oxidase/química , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Ácido Láctico/química , Suor/química , Dispositivos Eletrônicos Vestíveis
3.
Food Chem ; 302: 125338, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31434027

RESUMO

This study was designed to evaluate the baking performances of 25 edible dry bean (Phaseolus vulgaris L.) varieties and to investigate correlations among cookie features and rapid test indices (i.e., water and lactic acid retention capacities, oil binding capacity and Rapid Visco Analyzer indices). Two bean powder particle sizes (≤0.5 mm, ≤1.0 mm) were investigated. Cookies were evaluated in terms of nutritional, geometrical and textural properties. Bean powders doubled the amount of cookie protein and increased cookie resistant starch content. Baking potential varied according to bean genotype and powder particle size: coarse powders resulted in larger (+26%) and thinner (-19%) cookies characterized by easier breaking texture (fracture strengths of 41-157 vs. 48-226 kPa for fine powders). Water retention and oil binding capacities and pasting properties significantly (p < 0.05) correlated with cookie features. In conclusion, these accumulated findings can be used in designing value-added traditional and gluten-free cookies.


Assuntos
Phaseolus/química , Pós/química , Culinária , Dieta Livre de Glúten , Farinha , Ácido Láctico/análise , Ácido Láctico/química , Valor Nutritivo , Tamanho da Partícula , Amido/análise , Água/análise , Água/química
4.
Fitoterapia ; 139: 104389, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31669963

RESUMO

A new heterodimer, rynchopeterine F (1), a new natural product, rynchopeterine G (2), and eleven known phenolics were isolated from Blap rynchopetera Fairmaire, a kind of medicinal insect utilized by the Yi and Bai Nationality in Yunnan Province of China. Their structures were established on the basis of extensive spectroscopic analyses (1D and 2D NMR, HR-MS) along with calculated electronic circular dichroism method. Rynchopeterine F was a unusual heterodimer of a 3,4-dihudroxy phenylethanol unit fused to a 3,4-dihudroxy phenylacetyl group through two ester bonds with lactic acid, and rynchopeterine G was a 3,4-dihudroxy phenylethanyl monoester succinate. Attributed to the adjacent dihydroxyl grops, compounds 1 and 2 exhibited significant anti-radical activity with an IC50 value of 3.52 and 7.83 µg/mL for DPPH radical-scavenging, similar with that of the positive controls, vitamin C, 6.92 µg/mL and rutin, 8.28 µg/mL.


Assuntos
Besouros/química , Depuradores de Radicais Livres/farmacologia , Fenóis/farmacologia , Animais , China , Depuradores de Radicais Livres/isolamento & purificação , Ácido Láctico/química , Estrutura Molecular , Fenóis/isolamento & purificação , Álcool Feniletílico/química
5.
Environ Sci Pollut Res Int ; 26(36): 36236-36247, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31713134

RESUMO

Poly(L-lactic acid) (PLLA) can be used as an external electron donor in denitrification reactors to treat drinking water, aquaculture water, and industrial wastewater with an imbalanced carbon/nitrogen ratio. However, for PLLA to function in these applications, its chemical hydrolyzability requires improvement. Although the adjustment of the crystallinity (Xc) is effective in improving the hydrolyzability of PLLA, the condition for the Xc of PLLA, in which a sufficient amount of lactic acid is released for denitrification, must be clarified. Therefore, this study investigated the effective Xc range and optimal PLLA content as an electron donor for continuous nitrate removal in denitrification reactors. This study also explored the abundance, succession, and diversity of active denitrifying bacteria in denitrification reactors. The nitrate removal activity of activated sludge using the highly crystalline PLLA (Xc = 39.4%) was 1.8 mg NO3- -N g MLSS-1 h-1, which is 2.4 times higher than that using the nearly amorphous PLLA (Xc = 0.9%). During the 57 days of operation, the denitrification reactor with 3% (w/v) highly crystalline PLLA continued to completely remove nitrate, with a maximum nitrate removal activity of 22.8 mg NO3- -N g MLSS-1 h-1. The 16S rRNA amplicon sequencing and clone library analyses are using transcripts of two nitrite reductase genes, encoding cytochrome cd1 nitrite reductase, and copper-containing nitrite reductase revealed that bacteria belonging to the families Comamonadaceae, Rhodocyclaceae, and Alcaligenaceae were active denitrifying bacteria in the denitrification reactor using PLLA.


Assuntos
Bactérias/metabolismo , Reatores Biológicos/microbiologia , Desnitrificação , Nitratos/metabolismo , Poliésteres/metabolismo , Poluentes Químicos da Água/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biodegradação Ambiental , Biodiversidade , Desnitrificação/genética , Hidrólise , Ácido Láctico/química , Ácido Láctico/metabolismo , Nitrito Redutases/genética , Nitrito Redutases/metabolismo , Poliésteres/química , RNA Ribossômico 16S/genética , Eliminação de Resíduos Líquidos/normas
6.
Zhonghua Fu Chan Ke Za Zhi ; 54(10): 680-686, 2019 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-31648444

RESUMO

Objective: To investigate whether poly (lactic-co-glycolic acid) (PLGA) as protein delivery vehicles that encapsulate CC chemokine receptor 5 antibody (anti-CCR5) has more suppressive function on macrophages than single anti-CCR5 in mouse endometriosis model. Methods: The PLGA/anti-CCR5 nanoparticles were synthesized. The cumulative release of anti-CCR5 from PLGA/anti-CCR5 nanoparticles was evaluated. The mouse endometriosis model was established and divided into control group, anti-CCR5 group and PLGA/anti-CCR5 group. Meanwhile, ectopic endometrial cells (EEC) and macrophages isolated from peritoneal fluid were cultured in vitro. Flow cytometry was used to detect the proportion of macrophages in the peritoneal fluid of each group. The secretion of interleukin 10 (IL-10) and transforming growth factor ß (TGF-ß) in each group were determined by ELISA. The proliferation and infiltration of EEC were detected by 5-bromodeoxyuridine proliferation kit and matrigel invasion kit. Results: The PLGA/anti-CCR5 nanoparticles were successfully synthesized. The mouse endometriosis model was established and the EEC and macrophages were cultured. Compared with the anti-CCR5 without nanoparticles, the bioconjugate PLGA/anti-CCR5 nanoparticles could control the release of anti-CCR5 from day 3 to day 24. The proportion of macrophages in PLGA/anti-CCR5 group were gradually reduced compared with those in anti-CCR5 group (P<0.01), the ratios of day 7 [(4.5±1.5)%] and day 3 [(6.3±0.6)%], day 14 [(2.6±0.7)%] and day 7 were significantly different (P<0.01 and P<0.05). PLGA/anti-CCR5 reduced IL-10 and TGF-ß levels relative to anti-CCR5 (P<0.01),and decreased gradually on day 3, day 7, and day 14 (P<0.01). Anti-IL-10+anti-TGF-ß could reduce the proliferation [(70.8±7.6)%] and invasion ability [(50.2±9.1)%] of EEC (P<0.05). Conclusions: In mouse endometriosis model, PLGA/anti-CCR5 may inhibit the proliferation and invasion of EEC by inhibiting the secretion of IL-10 and TGF-ß by macrophages, suggesting that it provide a new idea for the treatment of clinical endometriosis.


Assuntos
Endometriose/tratamento farmacológico , Ácido Láctico/química , Nanopartículas/uso terapêutico , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/uso terapêutico , Receptores CCR5/uso terapêutico , Animais , Endometriose/imunologia , Feminino , Humanos , Camundongos , Nanopartículas/química , Resultado do Tratamento
7.
Biomed Mater Eng ; 30(4): 419-426, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31498119

RESUMO

BACKGROUND: The chemical properties of the oral environment have an appreciable influence on the in vivo degradation of CAD/CAM materials. OBJECTIVE: The aim of the present study was to investigate the effect of organic acids, heptane and ethanol (the food-simulating liquids) on CAD/CAM restorative materials. METHODS: Four CAD/CAM materials were selected: (1) 3M ESPE LAVA Ultimate, (2) VITA Enamic, (3) IPS e.max CAD, (4) VITA Suprinity. Seven different samples were fabricated in 15 × 4 × 1.2 mm dimensions from each material (n = 7, N = 140). The materials were conditioned for 7 days at 37 °C as follows: artificial saliva, 75% ethanol, heptane, 0.02 N citric acid, 0.02 N lactic acid in aqueous solution and were tested to obtain flexural strength, surface micro-hardness and wear characteristics. After conditioning, the flexural strength values were assessed using a universal testing machine (1 mm/min crosshead speed) and the fractured samples were used for determination of Vickers hardness values using a digital micro-hardness tester (100 g/10 s) and determination of wear using a chewing simulator. Two factor analysis of variance with interaction model and Tukey's post hoc test were used for statistical analysis. RESULTS: The highest mechanical property values were found for IPS e.max and VITA Suprinity and the lowest values were found for LAVA Ultimate. Organic acids negatively affected the mechanical properties of e.max CAD and Suprinity. Ethanol and heptane were more effective on LAVA Ultimate and Enamic. There were significant differences among groups (p < 0.05). CONCLUSION: The mechanical properties of CAD/CAM restorative materials are influenced by food-simulating liquids.


Assuntos
Cerâmica/química , Materiais Dentários/química , Materiais Biocompatíveis/química , Ácido Cítrico/química , Dureza , Humanos , Ácido Láctico/química , Teste de Materiais , Saliva/química , Estresse Mecânico , Propriedades de Superfície
8.
Int J Pharm ; 569: 118557, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31377405

RESUMO

This study describes the fabrication of chemically crosslinked pectin-based LA-co-MAA hydrogels through free radical polymerization technique for the colonic delivery of oxaliplatin. Methylene bisacrylamide was used as a crosslinking agent and ammonium persulfate as an initiator. The successful fabrication and drug loading were confirmed through Fourier transform infrared spectroscopy (FTIR). The thermal investigations through differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) suggested the higher thermal stability of the unloaded and OXP-loaded formulations as compared to the raw materials. X-ray diffraction (XRD) analysis showed a decrease in crystallinity after crosslinking. The swelling, drug loading, and drug release were increased with an increase in the concentration of pectin and lactic acid (LA) while methacrylic acid (MAA) displayed an inverse behavior. The in-vitro biodegradability was evaluated against lysozyme and collagenase. The results showed that the hydrogels were stable against blank PBS as compared to lysozyme and collagenase. MTT-assay proved that the blank hydrogels were cytocompatible while free OXP and OXP-loaded hydrogels displayed dose-dependent effect against Vero, MCF-7, and HCT-116 cell lines. The oral tolerability study in rabbits confirmed that the hydrogel dispersion was well-tolerable up to 3650 mg/kg of body weight without causing any histopathological or hematological changes when compared with the control group.


Assuntos
Sistemas de Liberação de Medicamentos , Hidrogéis/administração & dosagem , Ácido Láctico/administração & dosagem , Metacrilatos/administração & dosagem , Oxaliplatina/administração & dosagem , Pectinas/administração & dosagem , Animais , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/química , Sobrevivência Celular/efeitos dos fármacos , Colo/metabolismo , Feminino , Células HCT116 , Humanos , Hidrogéis/química , Concentração de Íons de Hidrogênio , Ácido Láctico/química , Células MCF-7 , Masculino , Metacrilatos/química , Oxaliplatina/química , Pectinas/química , Coelhos , Células Vero
9.
Carbohydr Polym ; 223: 115131, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31426964

RESUMO

Biodegradable multicomponent films based on poly(lactic acid) (PLA) and poly(3-hydroxybutyrate) (PHB) plasticized with oligomeric lactic acid (OLA), reinforced with synthetized cellulose nanocrystals (CNC) and modified by a natural additive with antimicrobial activity (carvacrol) were formulated and processed by extrusion. Morphological, mechanical, thermal, migration and barrier properties were tested to determine the effect of different components in comparison with neat poly(lactic acid). Results showed the positive effect of CNC in the five components based films, with the increase of the Young's modulus of the PLA_PHB_10Carv_15OLA, associated with an increase in the elongation at break (from 150% to 410%), by showing an OTR reduction of 67%. Disintegrability in compost conditions and enzymatic degradation were tested to evaluate the post-use of these films. All formulations disintegrated in less than 17 days, while proteinase K preferentially degraded the amorphous regions, and crystallinity degree of the nanocomposite films increased as a consequence of enzyme action.


Assuntos
/química , Hidroxibutiratos/química , Ácido Láctico/química , Nanopartículas/química , Poliésteres/química , Celulose/química , Tamanho da Partícula , Propriedades de Superfície
10.
Drug Metab Rev ; 51(4): 570-588, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296117

RESUMO

This review intended to comparatively explain and present the most important medical use and biological impact of poly-lactides and lactide-based composites. The utilization and degradation of compounds based on lactic acid and polylactides is described in detail. Understanding the metabolism and degradation phenomenon and the factors that potentially influence it is key to modulating their properties as well as their characteristics driven from the fabrication procedures and the fields of use. All these are commented according to the clinician's criteria. The current debate on the advantages and shortcomings of various resorbable polymeric materials categories is also analyzed, from the perspective of the users of resorbable polylactide-based biomaterials. The scientific literature comprises either distinct chemical and physical or specific animal or medical description of resorbable materials; so that in compensation, the present review covers all topics for the most appropriate comprehensive update of the reader.


Assuntos
Implantes Absorvíveis , Poliésteres/administração & dosagem , Poliésteres/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Humanos , Ácido Láctico/química , Poliésteres/metabolismo
11.
Biochim Biophys Acta Proteins Proteom ; 1867(11): 140255, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31349060

RESUMO

D-2-hydroxyglutaric aciduria is a neurometabolic disorder, characterized by the accumulation of D-2-hydroxyglutarate (D-2HG) in human mitochondria. Increased levels of D-2HG are detected in humans exhibiting point mutations in the genes encoding isocitrate dehydrogenase, citrate carrier, the electron transferring flavoprotein (ETF) and its downstream electron acceptor ETF-ubiquinone oxidoreductase or D-2-hydroxyglutarate dehydrogenase (hD2HGDH). However, while the pathogenicity of several amino acid replacements in the former four proteins has been studied extensively, not much is known about the effect of certain point mutations on the biochemical properties of hD2HGDH. Therefore, we recombinantly produced wild type hD2HGDH as well as two recently identified disease-related variants (hD2HGDH-I147S and -V444A) and performed their detailed biochemical characterization. We could show that hD2HGDH is a FAD dependent protein, which is able to catalyze the oxidation of D-2HG and D-lactate to α-ketoglutarate and pyruvate, respectively. The two variants were obtained as apo-proteins and were thus catalytically inactive. The addition of FAD failed to restore enzymatic activity of the variants, indicating that the cofactor binding site is compromised by the single amino acid replacements. Further analyses revealed that both variants form aggregates that are apparently unable to bind the FAD cofactor. Since, D-2-hydroxyglutaric aciduria may also result from a loss of function of either the ETF or its downstream electron acceptor ETF-ubiquinone oxidoreductase, ETF may serve as the cognate electron acceptor of reduced hD2HGDH. Here, we show that hD2HGDH directly reduces recombinant human ETF, thus establishing a metabolic link between the oxidation of D-2-hydroxyglutarate and the mitochondrial electron transport chain.


Assuntos
Oxirredutases do Álcool/química , Encefalopatias Metabólicas Congênitas/enzimologia , Mutação de Sentido Incorreto , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Substituição de Aminoácidos , Encefalopatias Metabólicas Congênitas/genética , Catálise , Flavoproteínas Transferidoras de Elétrons/química , Flavoproteínas Transferidoras de Elétrons/metabolismo , Glutaratos/química , Glutaratos/metabolismo , Humanos , Ácidos Cetoglutáricos/química , Ácidos Cetoglutáricos/metabolismo , Ácido Láctico/química , Ácido Láctico/metabolismo
12.
Drug Deliv ; 26(1): 595-603, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31195837

RESUMO

With high morbidity and death rates, liver cancer has become one of the most common cancers in the world. But, most chemotherapeutic anticancer drugs have high toxicity as well as low specificity. To improve the treatment modalities and enhance the therapeutic effect of liver cancer, a brand new liver-targeting nanoparticle (NP), Ent-11α-hydroxy-15-oxo-kaur-16-en-19-oic acid (5 F)-loaded cholic acid (CA)-functionalized star-shaped poly (lactic-co-glycolic acid) (PLGA)-polyethylene glycol (PEG)-lactobionic acid (LA) (5 F-loaded CA-PLGA-PEG-LA), was developed. The particle size, zeta potential, size distribution, surface morphology, drug loading content, drug encapsulation efficiency and drug release of 5 F-loaded NPs were characterized. Confocal microscopy and flow cytometry showed that the prepared NPs could be internalized by HepG2 cells. Furthermore, the cellular uptake efficiency of coumarin 6-loaded CA-PLGA-PEG-LA NPs was much better in compare with that of CA-PLGA-PEG and CA-PLGA NPs. Moreover, LA-conjugated NPs (CA-PLGA-PEG-LA NPs) enhanced fluorescence of HepG2 cells via ligand-mediated endocytosis. The antitumor effects of 5 F-loaded NPs were evaluated by the MTT assay in vitro and by a xenograft tumor model in vivo, demonstrating that targeted 5 F-loaded CA-PLGA-PEG-LA NPs were significantly superior to free 5 F and 5 F-loaded CA-PLGA-PEG NPs. All the results indicated the 5 F-loaded CA-PLGA-PEG-LA NPs can be employed as a novel potentially targeting drug delivery system for liver cancer therapy.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/química , Neoplasias Hepáticas/tratamento farmacológico , Fígado/efeitos dos fármacos , Nanopartículas/administração & dosagem , Nanopartículas/química , Polímeros/química , Animais , Linhagem Celular Tumoral , Ácido Cólico/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos/efeitos dos fármacos , Feminino , Células Hep G2 , Humanos , Lactatos/química , Ácido Láctico/química , Camundongos , Camundongos Nus , Tamanho da Partícula , Polietilenoglicóis/química , Ácido Poliglicólico/química
13.
Food Chem ; 293: 247-253, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151608

RESUMO

Physicochemical and thermal characteristics of concentrated lactose solutions containing 0.05, 1, or 4% (w/w) of three acids commonly used in the food industry, i.e., lactic, citric, and phosphoric acid, were studied. Properties of both lactose and water were affected by all acids studied. Thermographic analysis showed that interactions between water and acids hindered evaporation of water from most of lactose solutions. This effect was mostly related to the formation of a strong hydration layer around lactose molecules by hydrogen bonds. Acid-induced hydrolysis of lactose into glucose and galactose varied depending on the concentration, hydrolytic power of acids and molecular interactions in the system. The study concluded that the varying physical, chemical, structural and thermal characteristics of lactose as affected by the presence of different acids was mainly due to the manipulation of water-lactose interactions, whereas the hydrolysis of lactose by the acids plays a smaller role.


Assuntos
Ácido Cítrico/química , Ácido Láctico/química , Lactose/química , Ácidos Fosfóricos/química , Cromatografia Líquida de Alta Pressão , Ligações de Hidrogênio , Concentração de Íons de Hidrogênio , Hidrólise , Lactose/análise , Soluções/química , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Água/química
14.
Food Chem ; 295: 165-171, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174746

RESUMO

Deep eutectic solvents (DES) and aqueous glycerol were proposed as green alternatives to conventional solvents for the extraction of polyphenols from grapefruit peels. In order to increase the extraction kinetics and yields of polyphenols, high voltage electrical discharges (HVED) were used as a pre-treatment technology (energy varied between 7.27 and 218 kJ/kg). Results showed that the HVED energy input can be reduced, when the subsequent solid-liquid extraction was performed in 20% (w/v) aqueous glycerol or in DES (lactic acid: glucose) instead of water. The addition of glycerol has reduced the energy of the pre-treatment by 6 times. The same diffusivity of polyphenols (4 × 10-11 m2/s) was obtained in water from HVED pre-treated peels at 218 kJ/kg and in aqueous glycerol from pre-treated peels at 36 kJ/kg. The solubility of naringin, the main flavonoid compound of grapefruit peels in the solvents, was investigated through a theoretical modelling of its Hansen solubility parameters.


Assuntos
Citrus paradisi/química , Glicerol/química , Polifenóis/isolamento & purificação , Solventes/química , Cromatografia Líquida de Alta Pressão , Citrus paradisi/metabolismo , Eletricidade , Flavanonas/química , Flavonoides/química , Glucose/química , Ácido Láctico/química , Extração Líquido-Líquido , Polifenóis/análise , Solubilidade , Água/química
15.
Colloids Surf B Biointerfaces ; 181: 728-733, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31229799

RESUMO

The level of lactate and hypoxia inducible factor (HIF) in cells has effect on tumor growth and drug resistance. The glycolysis of tumors could be inhibited by reducing the expression of lactate dehydrogenase A (LDHA) or the mutual conversion of lactic acid and pyruvic acid. To develop a bifunctional nanoparticle as both the cleaner of lactate and attenuator of glycolysis, a NIR (near infrared) responsive nanoparticle (Mn-CuS@BSA-FA) was synthesized and characterized. The Mn-CuS@BSA-FA catalyzed the oxidation of lactate to pyruvate under NIR irradiation. In vitro assay results demonstrate that Mn-CuS@BSA-FA can decrease the activity of LDHA and attenuate the conversion of lactate to pyruvate. Moreover, Mn-CuS@BSA-FA can inhibit the expression of HIF-1 and decrease the ATP level in HepG-1 cells. Our work demonstrates that Mn-CuS@BSA-FA can be a NIR enhanced glycolytic inhibitor for cancer interventional treatment.


Assuntos
Cobre/química , Ácido Láctico/metabolismo , Compostos de Manganês/química , Nanocompostos/química , Animais , Bovinos , Ácido Fólico/química , Glicólise , Raios Infravermelhos , Ácido Láctico/química , Oxirredução , Tamanho da Partícula , Piruvatos/química , Piruvatos/metabolismo , Soroalbumina Bovina/química , Propriedades de Superfície
16.
J Mater Sci Mater Med ; 30(7): 78, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31222566

RESUMO

3D printing is a versatile technique widely applied in tissue engineering due to its ability to manufacture large quantities of scaffolds or constructs with various desired architectures. In this study, we demonstrated that poly (lactic acid) (PLA) scaffolds fabricated via fused deposition not only retained the original interconnected microporous architectures, the scaffolds also exhibited lower lactic acid dissolution as compared to the freeze-PLA scaffold. The 3D-printed scaffolds were then grafted with human bone morphogenetic protein-2 (BMP-2) via the actions of polydopamine (PDA) coatings. The loading and release rate of BMP-2 were monitored for a period of 35 days. Cellular behaviors and osteogenic activities of co-cultured human mesenchymal stem cells (hMSCs) were assessed to determine for efficacies of scaffolds. In addition, we demonstrated that our fabricated scaffolds were homogenously coated with PDA and well grafted with BMP-2 (219.1 ± 20.4 ng) when treated with 250 ng/mL of BMP-2 and 741.4 ± 127.3 ng when treated with 1000 ng/mL of BMP-2. This grafting enables BMP-2 to be released in a sustained profile. From the osteogenic assay, it was shown that the ALP activity and osteocalcin of hMSCs cultured on BMP-2/PDA/PLA were significantly higher when compared with PLA and PDA/PLA scaffolds. The methodology of PDA coating employed in this study can be used as a simple model to immobilize multiple growth factors onto different 3D-printed scaffold substrates. Therefore, there is potential for generation of scaffolds with different unique modifications with different capabilities in regulating physiochemical and biological properties for future applications in bone tissue engineering.


Assuntos
Bivalves , Proteína Morfogenética Óssea 2/química , Osteogênese , Poliésteres/química , Impressão Tridimensional , Tecidos Suporte/química , Animais , Regeneração Óssea , Linhagem Celular , Técnicas de Cocultura , Humanos , Concentração de Íons de Hidrogênio , Indóis/química , Ácido Láctico/química , Células-Tronco Mesenquimais/citologia , Polímeros/química , Porosidade , Engenharia Tecidual/métodos
17.
Biosens Bioelectron ; 137: 15-24, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31077986

RESUMO

Herein we report the use of scanning electrochemical microscopy (SECM) together with electrochemical and spectroscopic techniques to develop and characterise a stable and uniformly reactive chemically modified platinum electrode for NADH electrocatalysis. In order to achieve this, a range of different approaches for thionine entrapment within an electropolymerised poly (3,4-ethylendioxythiophene) (PEDOT) film were evaluated using SECM imaging in the presence of NADH, demonstrating the uniformity of the reactive layer towards NADH oxidation. The effect of electrolyte type and time scale employed during PEDOT electropolymerisation was examined with respect to thionine loading and the resulting charge transport diffusion coefficient (DCT) estimated via chronoamperometry. These studies indicated a decrease in DCT as thionine loading increased within the PEDOT film, suggesting that charge transport was diffusion limited within the film. Additionally, thionine functionalised nanotubes were formed, providing a stable support for lactate dehydrogenase entrapment while lowering the rate of thionine leaching, determined via SECM imaging. This enabled lactate determination at Eapp = 0.0 V vs Ag/AgCl over the range 0.25-5 mM in the presence of 1 mM NAD+.


Assuntos
Técnicas Biossensoriais , Catálise , Ácido Láctico/isolamento & purificação , L-Lactato Desidrogenase/química , Ácido Láctico/química , Microscopia Eletroquímica de Varredura , NAD/química , Oxirredução , Polímeros/química
18.
Molecules ; 24(10)2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31137761

RESUMO

Molecular dynamics simulations are used to study the transport of CO 2 , H 2 S and CH 4 molecules across environmentally friendly choline-benzoate and choline-lactate ionic liquids (ILs). The permeability coefficients of the considered molecules are calculated using the free energy and diffusion rate profiles. Both systems show the largest resistance to CH 4 , whereas more than 5 orders of magnitude larger permeability coefficients are obtained for the other two gas molecules. The CO 2 /CH 4 and H 2 S/CH 4 selectivity was estimated to be more than 10 4 and 10 5 , respectively. These results indicate the great potential of the considered ILs for greenhouse gas control.


Assuntos
Dióxido de Carbono/análise , Colina/química , Sulfeto de Hidrogênio/análise , Líquidos Iônicos/química , Metano/análise , Simulação de Dinâmica Molecular , Benzoatos/química , Difusão , Ácido Láctico/química , Permeabilidade , Termodinâmica
19.
Int J Biol Macromol ; 135: 314-327, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31125643

RESUMO

The present study isolated starch from corn and sorghum grains through wet milling procedure. Sorghum starch is considered an alternative to corn starch in future, due to similar functional properties. However, agronomically sorghum is a cheap input cost crop compared to sorghum and can grow in drought hit areas. Lactic acid and citric acid modifications along with heat-moisture treatments were performed on both sorghum and corn grains followed by their comparison in terms of functional, textural, thermal, pasting and digestibility characteristics. For both corn and sorghum starches, the resistant starch increased after chemical modifications. The RS content of acid and acid-heat moisture treated starches were in the range of 77.9-90%, significantly higher than those of native starches (64.6-68.8%). The modifications increased the gelatinization temperature, decreased the peak and cold paste viscosity of starches. Chewiness significantly reduced after lactic and citric acid treatment along with heat-moisture treatments. The crystallinity to amorphous ratio measured through Fourier Transform infrared reduced after all chemical treatments. Percent light transmittance was further reduced after heat-moisture treatments, however the effect on corn starch was more pronounced i.e. it declined from 16.5 to 5.2%. The acid-heat moisture treatments had considerably lowered the glycemic index of starch. The GI reduced from 74 to 49.7 and 60 to 48.5 when treated with acid in the presence of heat and moisture. Thus, these starches could be used in production of low-calorie foods.


Assuntos
Ácido Cítrico/química , Índice Glicêmico , Ácido Láctico/química , Sorghum/química , Amido/química , Zea mays/química , Fenômenos Químicos , Ácido Cítrico/farmacologia , Índice Glicêmico/efeitos dos fármacos , Hidrólise , Ácido Láctico/farmacologia , Tamanho da Partícula , Solubilidade , Análise Espectral , Amido/isolamento & purificação , Amido/ultraestrutura , Termodinâmica
20.
ACS Appl Mater Interfaces ; 11(19): 17167-17176, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31002219

RESUMO

Synergistic intercellular interactions have been widely acknowledged in tuning functional cell behaviors in vivo, and these interactions have inspired the development of a variety of scaffolds for regenerative medicine. In this paper, the promotion of Schwann cell (SC)-neurite interactions through the use of a nerve extracellular matrix-coated nanofiber composite in vitro was demonstrated using a cell culturing platform consisting of either random or aligned electrospun poly(l-lactic acid) nanofibers and decellularized peripheral nerve matrix gel (pDNM gel) from porcine peripheral nervous tissue. The pDNM-coated nanofiber platform served as a superior substrate for dorsal root ganglion culturing. Furthermore, SC migration was facilitated by pDNM gel coating on the nanofibers, accompanied with much faster axonal extension, in comparison with the effect of topographical guidance from the aligned electrospun fibers only. Finally, the decellularized nerve matrix promoted the ability of SCs to wrap around bundled neurites, triggering axonal remyelination toward nerve fiber functionalization.


Assuntos
Neurogênese/genética , Medicina Regenerativa , Células de Schwann/efeitos dos fármacos , Engenharia Tecidual , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/genética , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/crescimento & desenvolvimento , Humanos , Ácido Láctico/química , Nanofibras/química , Tecido Nervoso/efeitos dos fármacos , Tecido Nervoso/crescimento & desenvolvimento , Neurogênese/efeitos dos fármacos , Polímeros , Suínos , Tecidos Suporte/química
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