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1.
J Fluoresc ; 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39126609

RESUMEN

An efficient urea-assisted SC (solution-combustion) approach was used to synthesize a novel series of doped Ca0.5Bi3P2O10: xDy3+ nanophosphors (0.01-0.1 mol). The powdered materials were thoroughly investigated using structural and optical measures. 'Rietveld refinement' investigations found that the produced nanophosphor formed a triclinic system with the P -1 triclinic space group. An EDS (energy-dispersive spectral) study was conducted to determine the corresponding proportions of constituent elements of doped nanophosphors. The TEM (transmission electron microscopy) revealed aggregated particles with a standard size on the nanoscale. The PLE (Photoluminescence excitation) spectrum indicates that the indicated phosphors can be stimulated by NUV (near ultraviolet) illumination sources. The Dy3+-ions undergo transitions from (4F9/2 → 6H15/2 & 4F9/2 → 6H13/2) were recognized as (PL) spectra with an excitation of 353 nm revealed the presence of blue-yellow bands at 481, and 577 nm, correspondingly. Further, PL data was used to determine photometric metrics such as CCT (correlated color-temperature), CC (chromaticity-coordinates (x & y)), and CP (color-purity (%)), supporting their use in solid-state lighting and latent fingerprinting applications.

2.
Molecules ; 28(11)2023 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-37298897

RESUMEN

Growing consumer interest in healthy foods has led to an increased demand for bioactive compounds derived from eco-technologies. This review highlighted two emerging technologies, pressurized liquid extraction (PLE) and supercritical fluid extraction (SFE), which are based on clean processes aimed at recovering bioactive compounds from different food sources. We studied how the different processing conditions provide many advantages and a great opportunity to obtain compounds with antioxidant, antibacterial, antiviral, or antifungal activity from plant matrices and industrial biowaste, especially antioxidant compounds (anthocyanins and polyphenols) due to their important role in health promotion. Our research was conducted through a systematic search in different scientific databases related to the PLE and SFE topics. The review analyzed the optimal extraction conditions using these technologies, which lead to the efficient extraction of bioactive compounds, the use of different equipment, and recent combinations of SFE and PLE with other emerging technologies. This has given rise to the development of new technological innovations, new commercial applications, and the detailed recovery of various bioactive compounds extracted from different plant and marine life food matrices. These two environmentally friendly methodologies are fully valid and have great future application prospects in biowaste valorization. They represent a feasible technological tool that can promote the implementation of a circular economy model for the food industry. The underlying mechanisms of these techniques were discussed in detail and supported by current literature.


Asunto(s)
Cromatografía con Fluido Supercrítico , Eliminación de Residuos , Antioxidantes/farmacología , Alimentos , Antocianinas , Tecnología , Cromatografía con Fluido Supercrítico/métodos
3.
Mar Drugs ; 20(8)2022 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-36005521

RESUMEN

The extensive use of conventional antibiotics has led to the growing emergence of many resistant strains of pathogenic bacteria. Evidence suggests that cationic antimicrobial peptides (AMPs) have the greatest potential to serve as traditional antibiotic substitutes. Recent studies have also reported that certain AMPs have selective toxicity toward various types of cancer cells. The electrostatic attraction between the negatively charged membrane components and AMPs is believed to play a crucial role in the disruption of bacterial and cancer cell membranes. In the current study, we used a potent AMP called Pleurocidin (Ple) derived from winter flounder Pleuronectes americanus and its C-terminal-amidated derivative Pleurocidin-amide (Ple-a), and evaluated their antibacterial and anticancer activities. Our results indicated that both Ple and Ple-a exhibited significant antibacterial activity against a broad spectrum of Gram-positive and Gram-negative bacteria, especially marine pathogens, with MIC values ranging from 0.25 to 32 µg/mL. These peptides are also potent against several multidrug-resistant (MDR) bacterial strains, with MIC values ranging from 2 to 256 µg/mL. When used in combination with certain antibiotics, they exhibited a synergistic effect against MDR E. coli. Ple and Ple-a also showed notable cytotoxicity toward various cancer cell lines, with IC50 values ranging from 11 to 340 µM, while normal mouse fibroblast 3T3 cells were less susceptible to these peptides. Ple-a was then selected to study its anticancer mechanism toward A549 human lung adenocarcinoma cells. Western blot analysis and confocal microscopy showed that Ple-a could inhibit autophagy of A549 cells, and induce apoptosis 48 h after treatment. Our findings provided support for the future application of Ple-a as potential therapeutic agent for bacterial infections and cancer treatment.


Asunto(s)
Lenguado , Amidas/farmacología , Animales , Antibacterianos/farmacología , Péptidos Catiónicos Antimicrobianos/farmacología , Péptidos Antimicrobianos , Bacterias , Escherichia coli , Proteínas de Peces , Bacterias Gramnegativas , Bacterias Grampositivas , Humanos , Ratones , Pruebas de Sensibilidad Microbiana
4.
Sensors (Basel) ; 22(20)2022 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-36298125

RESUMEN

This article presents the development of a power loss emulation (PLE) system device to study and find ways of mitigating skin tissue heating effects in transcutaneous energy transmission systems (TETS) for existing and next generation left ventricular assist devices (LVADs). Skin thermal profile measurements were made using the PLE system prototype and also separately with a TETS in a porcine model. Subsequent data analysis and separate computer modelling studies permit understanding of the contribution of tissue blood perfusion towards cooling of the subcutaneous tissue around the electromagnetic coupling area. A 2-channel PLE system prototype and a 2-channel TETS prototype were implemented for this study. The heating effects resulting from power transmission inefficiency were investigated under varying conditions of power delivery levels for an implanted device. In the part of the study using the PLE setup, the implanted heating element was placed subcutaneously 6-8 mm below the body surface of in vivo porcine model skin. Two operating modes of transmission coupling power losses were emulated: (a) conventional continuous transmission, and (b) using our proposed pulsed transmission waveform protocols. Experimental skin tissue thermal profiles were studied for various levels of LVAD power. The heating coefficient was estimated from the porcine model measurements (an in vivo living model and a euthanised cadaver model without blood circulation at the end of the experiment). An in silico model to support data interpretation provided reliable experimental and numerical methods for effective wireless transdermal LVAD energization advanced solutions. In the separate second part of the study conducted with a separate set of pigs, a two-channel inductively coupled RF driving system implemented wireless power transfer (WPT) to a resistive LVAD model (50 Ω) to explore continuous versus pulsed RF transmission modes. The RF-transmission pulse duration ranged from 30 ms to 480 ms, and the idle time (no-transmission) from 5 s to 120 s. The results revealed that blood perfusion plays an important cooling role in reducing thermal tissue damage from TETS applications. In addition, the results analysis of the in vivo, cadaver (R1Sp2) model, and in silico studies confirmed that the tissue heating effect was significantly lower in the living model versus the cadaver model due to the presence of blood perfusion cooling effects.


Asunto(s)
Corazón Auxiliar , Calefacción , Porcinos , Animales , Transferencia de Energía , Simulación por Computador , Cadáver
5.
Molecules ; 27(16)2022 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-36014331

RESUMEN

Laurus nobilis L., known as laurel or bay leaf, is a Mediterranean plant which has been long known for exhibiting various health-beneficial effects that can largely be attributed to the polyphenolic content of the leaves. Pressurized liquid extraction (PLE) is a green extraction technique that enables the efficient isolation of polyphenols from different plant materials. Hence, the aim of this research was to determine optimal conditions for PLE (solvent, temperature, number of extraction cycles and static extraction time) of laurel leaf polyphenols and to assess the polyphenolic profile of the optimal extract by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) as well as to evaluate the antioxidant activity determined by FRAP, DPPH and ORAC assays. The optimal PLE conditions were 50% ethanol, 150 °C, one extraction cycle and 5 min static time. The polyphenolic extract obtained at optimal PLE conditions comprised 29 identified compounds, among which flavonols (rutin and quercetin-3-glucoside) were the most abundant. The results of antioxidant activity assays demonstrated that PLE is an efficient green technique for obtaining polyphenol-rich laurel leaf extracts with relatively high antioxidant activity.


Asunto(s)
Laurus , Polifenoles , Antioxidantes/química , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida , Laurus/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Polifenoles/química , Espectrometría de Masas en Tándem
6.
Molecules ; 27(9)2022 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-35566308

RESUMEN

Previous published data from our group showed the encouraging in vitro activities of six phenolic temozolomide (TMZ) ester analogues (ES8-ES12 and ES14) with up to a five-fold increase in potency compared to TMZ against glioblastoma multiform cell lines and TMZ-resistant O6-methylguanine-DNA methyl transferase (MGMT)-positive primary cells. This study investigated the stabilities of the six phenolic TMZ ester analogues in the presence of porcine liver esterase (PLE) as a hydrolytic enzyme, using high-performance liquid chromatography (HPLC), monitored by a diode-array detector (DAD). Determining the rates of hydrolysis of the esters provided a useful insight into the feasibility of progressing them to the next phase of drug development. Fifty percent of TMZ esters consisting of para nitro, chloro, phenyl and tolyl groups (ES9, ES10, ES12 and ES14) were hydrolysed within the first 4.2 min of PLE exposure, while the TMZ esters consisting of para methoxy and nitrile groups (ES8 and ES11) demonstrated increased stability, with 50% hydrolysis achieved in 7.3 and 13.7 min, respectively. In conclusion, the survival of these phenolic TMZ esters on route to the target site of a brain tumor would be a challenge, mainly due to the undesirable rapid rate of hydrolysis. These findings therefore pose a question regarding the effectiveness of these esters in an in vivo setting.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Animales , Antineoplásicos Alquilantes/farmacología , Neoplasias Encefálicas/tratamiento farmacológico , Línea Celular Tumoral , Cromatografía Líquida de Alta Presión , Metilasas de Modificación del ADN , Enzimas Reparadoras del ADN/genética , Resistencia a Antineoplásicos , Esterasas , Ésteres/farmacología , Glioblastoma/tratamiento farmacológico , Hígado/metabolismo , Porcinos , Temozolomida/farmacología , Proteínas Supresoras de Tumor/metabolismo
7.
Molecules ; 26(15)2021 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-34361828

RESUMEN

The parents' addictions and eating habits have a significant influence on the child's growth. The first stool of a newborn baby provides a large amount of information about xenobiotics transmitted by the mother's body. The analytical technique used in the study is ion chromatography with pulsed amperometric detection (IC-PAD). The biological samples, which were obtained from women staying in a maternity ward and their partners, revealed cyanide concentrations in urine samples spanning 1.30-25.3 µg L-1. Meanwhile, the results of the meconium samples were in the range of 1.54 µg L-1 to 24.9 µg L-1. Under the optimized chromatographic conditions, the IC-PAD system exhibited satisfactory repeatability (R < 3%, n = 3) and good linearity in the range of 1-100 µg L-1. Thus, it proved to be an effective tool for monitoring trace cyanide concentration in a series of human body fluid matrices, including meconium. Based on the literature review, this is the first application of the IC-PAD analytical technique for the determination of cyanide ions in meconium samples.


Asunto(s)
Cromatografía por Intercambio Iónico/métodos , Cianuros/análisis , Meconio/metabolismo , Urinálisis/métodos , Adulto , Femenino , Humanos , Recién Nacido , Masculino , Embarazo , Adulto Joven
8.
Anal Bioanal Chem ; 412(3): 589-599, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31838555

RESUMEN

The green microalga Haematococcus pluvialis has been widely studied due to its capacity to accumulate great amounts of astaxanthin, a high-value carotenoid with biological activities. In the present work, two green compressed fluid-based processes, pressurized liquid extraction (PLE) and supercritical antisolvent fractionation (SAF), are integrated to obtain an astaxanthin-enriched extract from this microalga. PLE was carried out using pressurized ethanol as solvent, for 20 min, at 10 MPa, and 50 °C as extraction temperature. Subsequently, the obtained extract was processed by SAF to further purify the carotenoid fraction. The SAF process was optimized using a 3-level factorial experimental design and considering three experimental variables: (i) CO2 pressure (10-30 MPa), (ii) percentage of water in the PLE extract (20-50%), and (iii) PLE extract/supercritical-CO2 flow rate ratio (0.0125-0.05). Total carotenoid content was evaluated in both extracts and raffinates. Best results were obtained at 30 MPa, 0.05 feed/SC-CO2 mass flow rate, and 20% (v/v) of water in the feed solution, achieving values of 120.3 mg g-1 carotenoids in extract (in the SAF extract fraction), which were significantly higher than those obtained in the original PLE extract. In parallel, a new fast two-dimensional comprehensive liquid chromatography (LC×LC) method was optimized to get the full carotenoid profile of these extracts in less than 25 min. This is the first time that the use of a C30 column is reported in an on-line LC×LC system. Graphical abstract.


Asunto(s)
Chlorophyta/química , Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Espectrofotometría Ultravioleta , Xantófilas/química
9.
Phytochem Anal ; 31(1): 119-130, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31304641

RESUMEN

INTRODUCTION: In recent years, an increasing interest in biological properties of sweet cherry (Prunus avium L.) stems has resulted in increased attention for advanced extraction techniques and their optimisation. OBJECTIVES: In the present study chemical profiles of P. avium stems extracts obtained by selected emerging technologies, such as pressurised liquid extraction (PLE) and supercritical fluid extraction (SFE), under different experimental conditions were compared. MATERIAL AND METHODS: All SFEs were carried out at 40°C in a dynamic mode with different solvent combinations (CO2 plus ethanol at 7 and 15%) and pressures (150 and 300 bar). The PLE experiments were performed in a static mode for all tested combinations of extraction solvent (ethanol-water from 0% to 100%) at temperatures ranging from 40 to 200°C. A complete analytical characterisation of cherry stem extracts was performed by high-performance liquid chromatography coupled to electrospray ionisation quadrupole time-of-flight mass spectrometry (HPLC-ESI-QTOF-MS). RESULTS: PLE showed to be more efficient than SFE removing a wide variety of compounds with different polarities being phenols the most abundant, whereas SFE resulted in a higher amount of fatty acids and derivatives. Chemical characterisation of the extracts was carried out by HPLC-ESI-QTOF-MS yielding in total 42 identified compounds, among which 22 compounds were identified in P. avium stems for the first time. CONCLUSION: These results point out the possibility of sweet cherry stem extracts to be incorporated in formulations manufactured by food and pharmaceutical industry. Also, these new thermal and high-pressure industrial technologies proved to be promising candidates in the valorisation of sweet cherry by-product.


Asunto(s)
Prunus avium , Cromatografía Líquida de Alta Presión , Fenoles , Extractos Vegetales , Espectrometría de Masa por Ionización de Electrospray
10.
Sensors (Basel) ; 20(22)2020 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-33217962

RESUMEN

We present a novel hybrid localization algorithm for wireless sensor networks in the absence of knowledge regarding the transmit power and path-loss exponent. Transmit power and the path-loss exponent are critical parameters for target localization algorithms in wireless sensor networks, which help extract target position information from the received signal strength. In the absence of information on transmit power and path-loss exponent, it is critical to estimate them for reliable deployment of conventional target localization algorithms. In this paper, we propose a simultaneous estimation of transmit power and path-loss exponent based on Kalman filter. The unknown transmit power and path-loss exponent are estimated using a Kalman filter with the tentatively estimated target position based solely on angle information. Subsequently, the target position is refined using a hybrid method incorporating received signal strength measurements based on the estimated transmit power and path-loss exponent. Our proposed algorithm accurately estimates transmit power and path-loss exponent and yields almost the same target position accuracy as the simulation results confirm, as the hybrid target localization algorithms with known transmit power and path-loss exponent. Simulation results confirm the proposed algorithm achieves 99.7% accuracy of the target localization performance with known transmit power and path-loss exponent, even in the presence of severe received signal strength measurement noise.

11.
Molecules ; 25(4)2020 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-32075048

RESUMEN

In this work a comparative study on phytochemical profiles of comfrey root extracts obtained by different extraction approaches has been carried out. Chemical profiles of extracts obtained by supercritical fluid (SFE), pressurized liquid (PLE), and conventional solid/liquid extraction were compared and discussed. Phytochemical composition was assessed by high-performance liquid chromatography coupled with electrospray time-of-flight mass spectrometry (HPLC-ESI-QTOF-MS/MS) identifying 39 compounds reported for the first time in comfrey root, mainly phenolic acids and fatty acids. The influence of different extraction parameters on phytochemical profiles of S. officinale root was investigated for all applied techniques. PLE and maceration, using alcohol-based solvents (aqueous methanol or ethanol), were shown to be more efficient in the recovery of more polar compounds. Greater numbers of phenolics were best extracted by PLE using 85% EtOH at 63 °C. The use of SFE and 100% acetone for 30 min enabled good recoveries of nonpolar compounds. SFE using 15% EtOH as a cosolvent at 150 bar produced the best recoveries of a significant number of fatty acids. The main compositional differences between extracts obtained by different extraction techniques were assigned to the solvent type. Hence, these results provided comprehensive approaches for treating comfrey root enriched in different phytochemicals, thereby enhancing its bioaccessibility.


Asunto(s)
Consuelda/química , Fenoles/aislamiento & purificación , Fitoquímicos/aislamiento & purificación , Extractos Vegetales/química , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Extracción Líquido-Líquido , Fenoles/química , Fenoles/clasificación , Fitoquímicos/química , Fitoquímicos/clasificación , Raíces de Plantas/química , Solventes/química , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem
12.
Molecules ; 25(14)2020 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-32708275

RESUMEN

Microalgal biomass is a sustainable and valuable source of lipids with omega-3 fatty acids. The efficient extraction of lipids from microalgae requires fast and alternative extraction methods, frequently combined with biomass pre-treatment by different procedures. In this work, Pressurized liquid extraction (PLE) was optimized and compared with traditional lipid extraction methods, Folch and Bligh and Dyer, and with a new Ultrasound Assisted Extraction (UAE) method for lipids from microalgae Isochrysis galbana. To further optimize PLE and UAE, enzymatic pre-treatment of microalga Isochrysis galbana was studied with commercial enzymes Viscozyme and Celluclast. No significant differences were found for lipid yields among different extraction techniques used. However, advanced extraction techniques with or without pre-treatment are a green, fast, and toxic solvent free alternative to traditional techniques. Lipid composition of Isochrysis was determined by HPLC-ELSD and included neutral and polar lipids, showing that each fraction comprised different contents in omega-3 polyunsaturated fatty acids (PUFA). The highest polar lipids content was achieved with UAE (50 °C and 15 min) and PLE (100 °C) techniques. Moreover, the highest omega-3 PUFA (33.2%), eicosapentaenoic acid (EPA) (3.3%) and docosahexaenoic acid (DHA) (12.0%) contents were achieved with the advanced technique UAE, showing the optimized method as a practical alternative to produce valuable lipids for food and nutraceutical applications.


Asunto(s)
Ácidos Docosahexaenoicos/química , Enzimas/metabolismo , Haptophyta/química , Lípidos/aislamiento & purificación , Suplementos Dietéticos , Ácido Eicosapentaenoico/química , Ácidos Grasos Omega-3/química , Extracción Líquido-Líquido , Microalgas/química , Presión , Solventes/química , Ondas Ultrasónicas
13.
J Food Sci Technol ; 57(3): 905-914, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32123411

RESUMEN

Considering the increasing consumer demand for healthy food, the extract from broccoli by-products was studied. To this aim, in the first step, three extraction techniques were compared in terms of extraction efficiency. The best method was the pressurized liquid extraction. Then, the extract microencapsulation was optimized in terms of type of wall material (between Capsul and maltodextrins), concentration of wall material (10-20-30%, w/v), core/wall material ratio (1:2, 1:5, 1:10, 1:20) and inlet temperature (80, 100, 130, 150, 170 °C). The optimal conditions were found with 10% maltodextrins as wall material, core/wall material ratio 1/2 at 80 °C. Finally, the obtained microencapsulated extract was added at 5% (w/w) to fish burgers. Results demonstrated that total phenolic content, total flavonoids and antioxidant activity of enriched fish products were significantly higher than the control burgers, thus confirming that both process and cooking did not greatly affect the nutritional properties of extracted compounds.

14.
Gastroenterology ; 155(1): 130-143.e15, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29604290

RESUMEN

BACKGROUND & AIMS: Congenital diarrheal disorders are rare inherited intestinal disorders characterized by intractable, sometimes life-threatening, diarrhea and nutrient malabsorption; some have been associated with mutations in diacylglycerol-acyltransferase 1 (DGAT1), which catalyzes formation of triacylglycerol from diacylglycerol and acyl-CoA. We investigated the mechanisms by which DGAT1 deficiency contributes to intestinal failure using patient-derived organoids. METHODS: We collected blood samples from 10 patients, from 6 unrelated pedigrees, who presented with early-onset severe diarrhea and/or vomiting, hypoalbuminemia, and/or (fatal) protein-losing enteropathy with intestinal failure; we performed next-generation sequencing analysis of DNA from 8 patients. Organoids were generated from duodenal biopsies from 3 patients and 3 healthy individuals (controls). Caco-2 cells and patient-derived dermal fibroblasts were transfected or transduced with vectors that express full-length or mutant forms of DGAT1 or full-length DGAT2. We performed CRISPR/Cas9-guided disruption of DGAT1 in control intestinal organoids. Cells and organoids were analyzed by immunoblot, immunofluorescence, flow cytometry, chromatography, quantitative real-time polymerase chain reaction, and for the activity of caspases 3 and 7. RESULTS: In the 10 patients, we identified 5 bi-allelic loss-of-function mutations in DGAT1. In patient-derived fibroblasts and organoids, the mutations reduced expression of DGAT1 protein and altered triacylglycerol metabolism, resulting in decreased lipid droplet formation after oleic acid addition. Expression of full-length DGAT2 in patient-derived fibroblasts restored formation of lipid droplets. Organoids derived from patients with DGAT1 mutations were more susceptible to lipid-induced cell death than control organoids. CONCLUSIONS: We identified a large cohort of patients with congenital diarrheal disorders with mutations in DGAT1 that reduced expression of its product; dermal fibroblasts and intestinal organoids derived from these patients had altered lipid metabolism and were susceptible to lipid-induced cell death. Expression of full-length wildtype DGAT1 or DGAT2 restored normal lipid metabolism in these cells. These findings indicate the importance of DGAT1 in fat metabolism and lipotoxicity in the intestinal epithelium. A fat-free diet might serve as the first line of therapy for patients with reduced DGAT1 expression. It is important to identify genetic variants associated with congenital diarrheal disorders for proper diagnosis and selection of treatment strategies.


Asunto(s)
Diacilglicerol O-Acetiltransferasa/genética , Duodeno/metabolismo , Fibroblastos/metabolismo , Hipoalbuminemia/genética , Trastornos del Metabolismo de los Lípidos/genética , Organoides/metabolismo , Enteropatías Perdedoras de Proteínas/genética , Células CACO-2 , Estudios de Casos y Controles , Caspasa 3/metabolismo , Caspasa 7/metabolismo , Niño , Preescolar , Consanguinidad , Dermis/citología , Diacilglicerol O-Acetiltransferasa/deficiencia , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Países Bajos , Forboles , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Secuencia de ADN , Turquía
15.
Biosci Biotechnol Biochem ; 83(6): 1124-1135, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30782084

RESUMEN

(R)-2-amino-2-ethoxycarbonylsuccinimide (ASI-2) is a key intermediate used in the pharmaceutical industry and is valuable for the industrial synthesis of ranirestat, which is a potent aldose reductase inhibitor. ASI-2 was synthesized in a process combining chemical synthesis and bioconversion. Bioconversion in this study is a key reaction, since optically active carboxylic acid derivative ((R)-1-ethyl hydrogen 3-benzyloxycarbonylamino-3-ethoxycarbonylsuccinate, Z-MME-AE) is synthesized from a prochiral ester, diethyl 2-benzyloxycarbonylamino-2-ethoxycarbonylsuccinate, Z-MDE-AE, at a theoretical yield of 100%. Upon screening for microorganisms that asymmetrically hydrolyze Z-MDE-AE, Bacillus thuringiensis NBRC13866 was found. A novel esterase EstBT that produces Z-MME-AE was purified from Bacillus thuringiensis NBRC13866 and was stably produced in Escherichia coli JM109 cells. Using EstBT rather than porcine liver esterase (PLE), ASI-2 was synthesized with a 17% higher total yield by a novel method, suggesting that the esterase EstBT is a PLE substitute enzyme and therefore, may be of interest for future industrial applications.


Asunto(s)
Inhibidores Enzimáticos/síntesis química , Esterasas/metabolismo , Hígado/enzimología , Pirazinas/síntesis química , Compuestos de Espiro/síntesis química , Secuencia de Aminoácidos , Animales , Bacillus thuringiensis/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Electroforesis en Gel de Poliacrilamida , Inhibidores Enzimáticos/química , Escherichia coli/genética , Hidrólisis , Pirazinas/química , Proteínas Recombinantes/genética , Compuestos de Espiro/química , Porcinos
16.
Neurosurg Focus ; 46(6): E8, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-31153152

RESUMEN

OBJECTIVEGamma Knife radiosurgery (GKRS) has been successfully used for the treatment of intracranial meningiomas given its steep dose gradients and high-dose conformality. However, treatment of skull base meningiomas (SBMs) may pose significant risk to adjacent radiation-sensitive structures such as the cranial nerves. Fractionated GKRS (fGKRS) may decrease this risk, but until recently it has not been practical with traditional pin-based systems. This study reports the authors' experience in treating SBMs with fGKRS, using a relocatable, noninvasive immobilization system.METHODSThe authors performed a retrospective review of all patients who underwent fGKRS for SBMs between 2013 and 2018 delivered using the Extend relocatable frame system or the Icon system. Patient demographics, pre- and post-GKRS tumor characteristics, perilesional edema, prior treatment details, and clinical symptoms were evaluated. Volumetric analysis of pre-GKRS, post-GKRS, and subsequent follow-up visits was performed.RESULTSTwenty-five patients met inclusion criteria. Nineteen patients were treated with the Icon system, and 6 patients were treated with the Extend system. The mean pre-fGKRS tumor volume was 7.62 cm3 (range 4.57-13.07 cm3). The median margin dose was 25 Gy delivered in 4 (8%) or 5 (92%) fractions. The median follow-up time was 12.4 months (range 4.7-17.4 months). Two patients (9%) experienced new-onset cranial neuropathy at the first follow-up. The mean postoperative tumor volume reduction was 15.9% with 6 patients (27%) experiencing improvement of cranial neuropathy at the first follow-up. Median first follow-up scans were obtained at 3.4 months (range 2.8-4.3 months). Three patients (12%) developed asymptomatic, mild perilesional edema by the first follow-up, which remained stable subsequently.CONCLUSIONSfGKRS with relocatable, noninvasive immobilization systems is well tolerated in patients with SBMs and demonstrated satisfactory tumor control as well as limited radiation toxicity. Future prospective studies with long-term follow-up and comparison to single-session GKRS or fractionated stereotactic radiotherapy are necessary to validate these findings and determine the efficacy of this approach in the management of SBMs.


Asunto(s)
Irradiación Craneana , Neoplasias Meníngeas/cirugía , Meningioma/cirugía , Radiocirugia , Neoplasias de la Base del Cráneo/cirugía , Anciano , Edema Encefálico/etiología , Terapia Combinada , Craneotomía , Fraccionamiento de la Dosis de Radiación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Neoplasias Meníngeas/radioterapia , Meningioma/radioterapia , Persona de Mediana Edad , Posicionamiento del Paciente , Radiocirugia/métodos , Estudios Retrospectivos , Carga Tumoral
17.
Int J Mol Sci ; 20(22)2019 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-31717968

RESUMEN

The bile acid-phospholipid conjugate ursodeoxycholyl-lysophosphatidylethanolamide (UDCA-LPE) was shown to have anti-inflammatory, antisteatotic, and antifibrotic properties, rendering it as a drug targeting non-alcoholic steatohepatitis (NASH). On a molecular level, it disrupted the heterotetrameric fatty acid uptake complex localized in detergent-resistant membrane domains of the plasma membrane (DRM-PM). However, its mode of action was unclear. Methodologically, UDCA-LPE was incubated with the liver tumor cell line HepG2 as well as their isolated DRM-PM and all other cellular membranes (non-DRM). The membrane cholesterol and phospholipids were quantified as well as the DRM-PM protein composition by Western blotting. The results show a loss of DRM-PM by UDCA-LPE (50 µM) with a 63.13 ± 7.14% reduction of phospholipids and an 81.94 ± 8.30% reduction of cholesterol in relation to mg total protein. The ratio of phospholipids to cholesterol changed from 2:1 to 4:1, resembling those of non-DRM fractions. Among the members of the fatty acid uptake complex, the calcium-independent membrane phospholipase A2 (iPLA2ß) abandoned DRM-PM most rapidly. As a consequence, the other members of this transport system disappeared as well as the DRM-PM anchored fibrosis regulating proteins integrin ß-1 and lysophospholipid receptor 1 (LPAR-1). It is concluded that UDCA-LPE executes its action by iPLA2ß removal from DRM-PM and consequent dissolution of the raft lipid platform.


Asunto(s)
Colesterol/metabolismo , Lisofosfolípidos/farmacología , Microdominios de Membrana/efectos de los fármacos , Fosfolipasas A2/metabolismo , Ácido Ursodesoxicólico/análogos & derivados , Células Hep G2 , Humanos , Integrina beta1/metabolismo , Microdominios de Membrana/metabolismo , Receptores del Ácido Lisofosfatídico/metabolismo , Ácido Ursodesoxicólico/farmacología
18.
Molecules ; 24(17)2019 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-31461900

RESUMEN

The olive oil industry produces large volumes of wastes, which are also potential sources of bioactive compounds by developing healthy and/or functional foods. Extraction of phenolic compounds from the residues of the olive oil is mainly carried out with solvents. However, there is currently a growing public awareness about the use of organic solvents in food processing, which has pointed out the need for the application of clean technologies such as pressurized liquid extraction (PLE). Therefore, the aim of this research was to optimize the phenolic compound extraction from olive pomace by PLE, establishing the qualitative and quantitative phenolic profile by HPLC-ESI-TOF/MS. The extraction design to recover phenolics from olive pomace demonstrates a great compositional variability of PLE extracts obtained under different experimental conditions. Indeed, quantitative results have pointed out the selectivity of PLE extraction when this technique is applied to the treatment of olive pomace. PLE-optimized conditions showed higher total phenolic compound content than conventional extraction (1659 mg/kg d.w. and 281.7 mg/kg d.w., respectively). Among these phenolics, the quantity of secoiridoids and flavonoids in the optimized PLE extract was three and four times higher than in conventional extracts. Furthermore, optimal PLE conditions allowed to obtain an enriched hydroxytyrosol extract which was not detected in the conventional one.


Asunto(s)
Aceite de Oliva/análisis , Fenoles/análisis , Cromatografía Líquida de Alta Presión/métodos , Flavonoides/química , Extracción Líquido-Líquido/métodos , Solventes/química
19.
Molecules ; 24(5)2019 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-30857290

RESUMEN

Sclerocarya birrea is a tree indigenous to Southern Africa with significant importance in rural livelihoods for food, medicine, and carving. The bark, which contains 10⁻20% tannin, provides several pharmacological benefits as an antidiabetic, anti-inflammatory, antimicrobial, anti-atherogenic, and antioxidant medication, among others. This study compared different extraction techniques used to recover bioactive compounds from marula bark. For this purpose, solid⁻liquid extraction, supercritical fluid extraction (SFE), and pressurized liquid extraction (PLE) were performed under selected conditions, using only "food-grade" solvents. The potential use of the proposed extraction methodologies was evaluated in term of yield, and the individual phenolic composition determined by HPLC⁻ESI⁻TOF⁻MS. PLE provided a high extraction yield in all experimental conditions. With regard to bioactive compounds composition, a total of 71 compounds, a significant percentage of which in a galloyl form, were distributed in five major categories. The largest number of compounds, mostly flavonoid aglycones, were extracted by PLE, generally when the extraction was developed at low temperatures. SFE did prove effective as a way of extracting antidiabetic proanthocyanidins. Advanced extraction techniques represent a powerful tool to obtain bioactive compounds from S. birrea bark, which can be used as supplements or food ingredients, promoting the valorization of this crop.


Asunto(s)
Anacardiaceae/química , Hipoglucemiantes/química , Corteza de la Planta/química , Extractos Vegetales/química , Antioxidantes/química , Cromatografía con Fluido Supercrítico , Fitoterapia
20.
Fetal Pediatr Pathol ; 38(6): 534-537, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31215290

RESUMEN

Introduction: A genetic cause of the protein-losing enteropathy (PLE) disease Diarrhea 10 (DIAR10) are mutations in the recently described PLVAP (plasmalemma vesicle protein). Case report: An infant with fatal PLE had a novel homozygous frameshift mutation (c.339dupT; p.Ala114Cysfs*9) leading to a premature stop codon in exon 1 of the PLVAP (NM_031310) gene detected by Whole Exome Sequencing (WES). Conclusion: The frameshift mutation (PLVAP; c.339dupT; p.Ala114Cysfs*9) we have described in our patient has not been previously reported. This is the fifth case reported with a mutation in PLVAP associated with PLE and DIAR10.


Asunto(s)
Proteínas Portadoras/genética , Exones/genética , Mutación del Sistema de Lectura/genética , Enteropatías Perdedoras de Proteínas/genética , Femenino , Homocigoto , Humanos , Lactante , Mutación/genética , Linaje , Enteropatías Perdedoras de Proteínas/diagnóstico
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