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1.
Langmuir ; 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38319714

RESUMEN

Zwitterionic silica coatings for surface functionalization are greatly prominent because of their simple and fast preparation, high availability, and effective antifouling properties. In this work, two zwitterionic sulfobetaine silane coatings, i.e., mono-SBSi and tris-SBSi, were deposited on glass surfaces and tested for antifouling of biological material and biofilm using human cancer cell and seawater, respectively. The used zwitterionic precursors mono-SBSi and tris-SBSi differ by the number of hydrolyzable silane groups: mono-SBSi contains one trimethoxysilane group, whereas tris-SBSi contains three of these functions. First, X-ray photoelectron spectroscopy indicates the successful grafting of zwitterionic coatings onto a glass surface. Characterization using atomic force microscopy shows the different morphologies and roughness of the two coatings. The glass surface became more hydrophilic after the grafting of zwitterionic coatings than the bare glass substrate. The antifouling properties of two coatings were evaluated via human cancer cell adsorption. Interestingly, the tris-SBSi coating displays a significantly lower level of cell adsorption compared to that of both mono-SBSi coating and the non-modified control surface. The same trend was observed for biofilm formation in seawater. Finally, the toxicity of mono-SBSi and tris-SBSi coatings was evaluated on zebrafish embryos, indicating the good biocompatibility of both coatings. Our results indicate interesting antifouling properties of zwitterionic coatings. The chemical constitution of the used precursor has an impact on the antifouling properties of the formed coating: the tris-SBSi-based zwitterionic silica coatings display improved antifouling properties compared to those of the mono-SBSi-based coating. Besides, the use of trisilylated precursors should result in the formation of more resistant and robust coatings due to the higher number of grafting functions. For all these reasons, we anticipate that tris-SBSi coatings will open new perspectives for antifouling applications for biological environments and implants.

2.
Biomacromolecules ; 25(6): 3261-3270, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38752976

RESUMEN

Two different poly(benzylmalate) biopolymers, a hydrophobic non-PEGylated (PMLABe73) and an amphiphilic PEGylated derivative (PEG42-b-PMLABe73), have been used to encapsulate a phthalocyanine chosen for its substitution pattern that is highly suitable for photodynamic therapy. Different phthalocyanine/(co)polymers ratios have been used for the nanoprecipitation. A set of six nanoparticles has been obtained. If the amphiphilic PEGylated copolymer proved to be slightly more efficient for the encapsulation and to lower the aggregation of the phthalocyanine inside the nanoparticles, it is, however, the hydrophobic PMLABe73-based nanoparticles that exhibited the best photodynamic efficiency.


Asunto(s)
Indoles , Isoindoles , Fotoquimioterapia , Indoles/química , Fotoquimioterapia/métodos , Biopolímeros/química , Nanopartículas/química , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Polímeros/química , Polietilenglicoles/química , Interacciones Hidrofóbicas e Hidrofílicas
3.
Methods ; 186: 90-96, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32640315

RESUMEN

Many studies on beef nutritional qualities require the quantification of intramuscular fat. To reduce the sample amount, solvent use and time of analysis, two alternative methods to the Folch et al. (1957) reference method were studied: a miniaturised Folch's method and a near-infrared spectroscopic method. Performances and acceptability limits were evaluated with accuracy profiles for each of the methods. Equations to correct bias between the alternative and reference methods were calculated. Uncertainties associated with measurements were determined, and the validity domains were defined. From a previous set of studies, the ability of each method to discriminate samples from bovines of different breeds or receiving diverse treatments was tested. The validity domain of the miniaturised Folch's method ranged from 1.9 to 13.8 g of total lipids/100 g of tissue, and that of the near-infrared spectroscopic method ranged from 4.8 to 13.8 g of total lipids/100 g of tissue, with less than 20% difference from the reference method's results. Thus, the two alternative methods could be used depending on the research objectives: the miniaturised Folch's method could be used for detailed quantification of intramuscular fat and the near-infrared spectroscopic method for a quick classification of a large number of muscles. The precise knowledge of uncertainties associated with each measurement was determined, and perfect continuity with the results obtained so far with the reference Folch's method was confirmed.


Asunto(s)
Laboratorios , Lípidos/análisis , Músculo Esquelético/química , Carne Roja/normas , Espectroscopía Infrarroja Corta/veterinaria , Animales , Calibración , Bovinos
4.
Acta Cardiol ; 72(6): 664-668, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28656798

RESUMEN

Ivabradine is an original drug that has been approved in two indications (systolic heart failure and angina). The aim of this short review is to draw the attention of clinician prescribers to the evidence base of ivabradine. Three large randomized trials testing ivabradine versus placebo have been performed. The BEAUTIFUL and SIGNIFY trials were in fact negative in the treatment of angina while the SHIFT trial found a marginal benefit of ivabradine over placebo in the treatment of heart failure. These important results are put into perspective in order to improve the assessment of risk-cost/benefit balances when ivabradine is considered. Ideally, a further clinical trial investigating the use of ivabradine in heart failure should be carried out with optimal treatment of the patient population in order to identify the subgroup of patients who respond to ivabradine.


Asunto(s)
Angina de Pecho/tratamiento farmacológico , Insuficiencia Cardíaca/tratamiento farmacológico , Ivabradina/uso terapéutico , Volumen Sistólico/fisiología , Angina de Pecho/complicaciones , Angina de Pecho/fisiopatología , Fármacos Cardiovasculares/uso terapéutico , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/fisiopatología , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
5.
Gastroenterology ; 140(4): 1199-1207.e1-2, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21199650

RESUMEN

BACKGROUND & AIMS: Ferroportin disease is characterized by iron overload. It has an autosomal-dominant pattern of inheritance and has been associated with mutations in the SLC40A1 gene, which encodes the cellular iron exporter ferroportin. Since the first description in 2001, about 30 mutations have been reported; the heterogeneity of ferroportin disease phenotypes has led to the hypothesis that the nature of the mutation affects the function of the protein in different ways. We studied genotypes and phenotypes of a large cohort of patients with ferroportin disease. METHODS: We studied clinical, biochemical, imaging, histologic, and genetic data from 70 affected subjects from 33 families with 19 mutations. RESULTS: We found that ferroportin disease, at the time of diagnosis, has limited consequences in the absence of cofactors. Data indicated that transferrin saturation, which correlated with fibrosis and levels of alanine aminotransferase, might be a marker of disease severity. Although the study was performed in a large number of families, we observed incomplete penetrance and no correlation between genotypes and phenotypes. CONCLUSIONS: Members of families with ferroportin disease should be screened for biochemical parameters of iron metabolism as well as genotype to detect silent mutations that might cause disease with acquired or genetic cofactors. Patients should be followed up long term to identify potential complications of the disease.


Asunto(s)
Proteínas de Transporte de Catión/genética , Hemocromatosis/genética , Caracteres Sexuales , Adolescente , Adulto , Anciano , Femenino , Proteínas Ligadas a GPI/genética , Pruebas Genéticas , Genotipo , Hemocromatosis/diagnóstico , Proteína de la Hemocromatosis , Humanos , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/genética , Masculino , Persona de Mediana Edad , Mutación , Linaje , Fenotipo , Receptores de Transferrina/genética , Índice de Severidad de la Enfermedad , Transferrina/metabolismo , Adulto Joven
6.
Foods ; 11(16)2022 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-36010493

RESUMEN

To characterize carcass and meat attributes, such as beef eating quality in specific farming conditions, 31 young grass-fed crossbred Angus x Salers cattle in two farming systems (a mono-cattle system versus a mixed system with beef cattle and sheep) were used in this study. Three muscle cuts (striploin-m. longissimus dorsi et thoracis; bolar blade-m. triceps brachii caput longum; internal flank plate-m. obliquus internus abdominis) were used for consumer eating quality testing and striploin was used for panelist eating quality assessment, and objective measurements [Warner-Bratzler shear force (WBSF) and fatty acid (FA) and antioxidant contents]. Results indicated that the farming system had no impact on carcass characteristics or meat quality, but it tended to affect FA content, which is likely explained by between-system differences in animal maturity (assessed by ossification score). Animal gender had significant effects on three eating quality traits evaluated by untrained consumers, with higher flavor liking, overall liking, and overall meat eating quality (MQ4) scores in females than in males. Additionally, FA contents were correlated with sensory quality traits to varying extents: consumer-scored tenderness, flavor, and overall liking were mainly positively correlated with ω-3 and ω-6 polyunsaturated fatty acid (PUFA) contents, and panelist-evaluated tenderness and abnormal flavor were more positively correlated with total lipids, saturated fatty acid (SFA), and monounsaturated fatty acid (MUFA) contents. Overall, this study showed that specific grass-fed crossbred Angus x Salers cattle can produce lean meat rich in ω-3 PUFAs with a low ω-6/ω-3 ratio and with "better than average" beef eating quality.

7.
Life (Basel) ; 12(12)2022 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-36556409

RESUMEN

BACKGROUND: In addition to their great optical properties, nanodiamonds (NDs) have recently proved useful for two-photon-excited photodynamic therapy (TPE-PDT) applications. Indeed, they are able to produce reactive oxygen species (ROS) directly upon two-photon excitation but not with one-photon excitation; Methods: Fluorescent NDs (FNDs) with a 100 nm diameter and detonation NDs (DNDs) of 30 nm were compared. In order to use the gems for cancer-cell theranostics, they were encapsulated in a bis(triethoxysilyl)ethylene-based (ENE) periodic mesoporous organosilica (PMO) shell, and the surface of the formed nanoparticles (NPs) was modified by the direct grafting of polyethylene glycol (PEG) and amino groups using PEG-hexyltriethoxysilane and aminoundecyltriethoxysilane during the sol-gel process. The NPs' phototoxicity and interaction with MDA-MB-231 breast cancer cells were evaluated afterwards; Results: Transmission electronic microscopy images showed the formation of core-shell NPs. Infrared spectra and zeta-potential measurements confirmed the grafting of PEG and NH2 groups. The encapsulation of the NDs allowed for the imaging of cancer cells with NDs and for the performance of TPE-PDT of MDA-MB-231 cancer cells with significant mortality. CONCLUSIONS: Multifunctional ND@PMO core-shell nanosystems were successfully prepared. The NPs demonstrated high biocompatibility and TPE-PDT efficiency in vitro in the cancer cell model. Such systems hold good potential for two-photon-excited PDT applications.

8.
ACS Appl Mater Interfaces ; 13(26): 30337-30349, 2021 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-34159778

RESUMEN

The efficient, versatile, and straightforward synthesis of the first N-alkyl analogues of induline 3B (8a and 8b) is reported. Thanks to the introduction of lipophilic substituents and their attractive photophysical properties (far-red emission and production of singlet oxygen), phenazinium 8b can be used as a theranostic agent and shows, at very low concentrations (100 nM), a remarkable ability to (i) image cells and zebrafish embryos with high quality under both mono- (514 nm) and biphotonic (790 and 810 nm) excitations, (ii) efficiently and quickly penetrate cancer cells rather than healthy fibroblasts, and (iii) induce a total or almost total cancer cell death in vitro and in vivo after illumination (λexc = 540-560 nm). The molecular structure of 8b is based on a triamino-phenazinium core only, with no need for additional components, highlighting the emergence of a minimalistic and versatile class of fluorescent probes for targeted photodynamic cancer therapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Colorantes Fluorescentes/uso terapéutico , Fenazinas/uso terapéutico , Fármacos Fotosensibilizantes/uso terapéutico , Animales , Antineoplásicos/síntesis química , Antineoplásicos/metabolismo , Antineoplásicos/efectos de la radiación , Línea Celular Tumoral , Fibroblastos/metabolismo , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/metabolismo , Colorantes Fluorescentes/efectos de la radiación , Humanos , Luz , Neoplasias/diagnóstico por imagen , Neoplasias/tratamiento farmacológico , Fenazinas/síntesis química , Fenazinas/metabolismo , Fenazinas/efectos de la radiación , Fotoquimioterapia , Fármacos Fotosensibilizantes/síntesis química , Fármacos Fotosensibilizantes/metabolismo , Fármacos Fotosensibilizantes/efectos de la radiación , Medicina de Precisión/métodos , Oxígeno Singlete/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Pez Cebra
9.
Food Chem ; 309: 125668, 2020 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-31690510

RESUMEN

Normand cull-cows received a diet enriched in n-3 polyunsaturated fatty acids (PUFA), known to enhance nutritional quality, but to decrease beef lipid stability. Half of the cows received a supplementation of vitamin E and plant extracts rich in polyphenols during the finishing period. Half of each feeding group was slaughtered under limited, the others under added stress conditions. Longissimus thoracis (LT) and Semitendinosus (ST) were evaluated after storage under air, or 70% O2/30% CO2 or vacuum conditions. Irrespectively of diet, pre-slaughter stress i) increased post-mortem malondialdehyde (MDA) formation except in vacuum-stored meat, ii) decreased vitamin A levels in the LT, iii) decreased vitamin E levels in meat stored in 70% O2/30% CO2 and total anti-oxidant status in vacuum stored meat. Effects were global; dietary supplementation with vitamin E and plant extracts was associated with lower MDA levels and MetMb percentage and higher levels of vitamin A and E.


Asunto(s)
Embalaje de Alimentos/métodos , Peroxidación de Lípido/efectos de los fármacos , Carne/análisis , Extractos Vegetales/química , Polifenoles/farmacología , Vitamina E/farmacología , Animales , Antioxidantes/química , Bovinos , Cromatografía Líquida de Alta Presión , Suplementos Dietéticos , Femenino , Malondialdehído/análisis , Vacio , Vitamina E/análisis
10.
Data Brief ; 30: 105409, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32274408

RESUMEN

This data article presents a dataset with 34 values of the fatty acids composition and of indicators of lipid oxidation determined in the Longissimus dorsi and Semitendinosus from 71 Normand cull-cows at slaughter, after muscle aging and after meat storage periods under different packaging conditions. Cows were subjected to 3 feeding diets and 2 slaughter protocols relative to pre-slaughter stress. The indicators of lipids, FA composition, antioxidative enzymes activities, antioxidative status and global lipid oxidation of the muscles, and meat at different time points and under different aging and storage conditions, may be used to increase our understanding of the evolution of oxidation and consequences on color development. The last research article published on part of these data [1] is available for some interpretive insights: https://doi.org/10.1016/j.foodchem.2019.125668.

11.
J Mater Chem B ; 8(7): 1472-1480, 2020 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-31995094

RESUMEN

Herein hybrid silica nanoparticles have been engineered to direct the sequential delivery of multiple chemotherapeutic drugs in response to external stimuli such as variations in pH. The nanocarriers consist of conventional MCM-41-type nanoparticles, which have been functionalised with an organic ligand (or stalk) grafted onto the external surface. The stalk is designed to "recognise" a complementary molecule, which serves as a "cap" to block the pores of the nanoparticles. First, camptothecin is introduced into the pores by diffusion prior to capping the pore apertures via molecular recognition. The cap, which is a derivative of 5-fluorouracil, serves as a second cytotoxic drug for synergistic chemotherapy. In vitro tests revealed that negligible release of the drugs occurred at pH 7.4, thus avoiding toxic side effects in the blood stream. In contrast, the stalk/cap complex is destabilised within the endolysosomal compartment (pH 5.5) of cancer cells, where release of the drugs was demonstrated. Furthermore, this environmentally responsive system exhibited a synergistic effect of the two drugs, where the pH-triggered release of the cytotoxic cap followed by diffusion-controlled release of the drug cargo within the pores led to essentially complete elimination of breast cancer cells.


Asunto(s)
Antineoplásicos/farmacología , Sistemas de Liberación de Medicamentos , Fluorouracilo/farmacología , Nanopartículas/química , Dióxido de Silicio/química , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos/química , Ensayos de Selección de Medicamentos Antitumorales , Fluorouracilo/química , Humanos , Células MCF-7 , Estructura Molecular , Imagen Óptica , Tamaño de la Partícula , Propiedades de Superficie , Células Tumorales Cultivadas
12.
Nanomaterials (Basel) ; 10(8)2020 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-32708042

RESUMEN

In this work, we exploit the versatile function of cationic phosphonium-conjugated polythiophenes to develop multifunctional platforms for imaging and combined therapy (siRNA delivery and photodynamic therapy). The photophysical properties (absorption, emission and light-induced generation of singlet oxygen) of these cationic polythiophenes were found to be sensitive to molecular weight. Upon light irradiation, low molecular weight cationic polythiophenes were able to light-sensitize surrounding oxygen into reactive oxygen species (ROS) while the highest were not due to its aggregation in aqueous media. These polymers are also fluorescent, allowing one to visualize their intracellular location through confocal microscopy. The most promising polymers were then used as vectors for siRNA delivery. Due to their cationic and amphipathic features, these polymers were found to effectively self-assemble with siRNA targeting the luciferase gene and deliver it in MDA-MB-231 cancer cells expressing luciferase, leading to 30-50% of the gene-silencing effect. In parallel, the photodynamic therapy (PDT) activity of these cationic polymers was restored after siRNA delivery, demonstrating their potential for combined PDT and gene therapy.

13.
Rheumatology (Oxford) ; 48(7): 779-84, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19416945

RESUMEN

OBJECTIVES: The aim of this study was to investigate the influence of age at disease onset in the outcome of paediatric SLE (pSLE). METHODS: Fifty-six patients with pSLE, divided into three groups (pre-pubertal, peripubertal and post-pubertal onset), were studied. The SDI (SLICC/ACR Damage Index for SLE), patients' characteristics, disease manifestations and treatments were compared using Fisher's exact test and Kruskal-Wallis test. Kaplan-Meier curves were constructed to compare the risk of damage occurrence. RESULTS: The risk of damage (SDI >or=1) significantly decreased when age at disease onset increased (89% in pre-pubertal pSLE, 57% in peripubertal pSLE and 38% in post-pubertal pSLE). This excess of risk was found in all disease duration intervals studied (1-3, 3-5, 5-8, 8-10, >10 years) and at the end of follow-up. Kaplan-Meier curves indicated a higher and earlier risk of damage in younger patients. Young children showed higher frequency of autoimmune family history. The frequency of neuropsychiatric disorders and damages decreased with age at disease onset (P < 0.05). Cumulative duration of high-dose prednisone (> 0.5 mg/kg/day) and number of immunosuppressive drugs used that seem to contribute to damage significantly increased when age at disease onset decreased. CONCLUSIONS: The risk of damage is inversely correlated with age at disease onset in pSLE. The poorer outcome observed in younger children may be explained by a more severe disease expression, may be a higher infectious susceptibility, and a more aggressive therapy, particularly within the first 6 months of disease course.


Asunto(s)
Lupus Eritematoso Sistémico/epidemiología , Adolescente , Edad de Inicio , Causas de Muerte , Niño , Femenino , Humanos , Inmunosupresores/efectos adversos , Inmunosupresores/uso terapéutico , Estimación de Kaplan-Meier , Lupus Eritematoso Sistémico/tratamiento farmacológico , Lupus Eritematoso Sistémico/mortalidad , Vasculitis por Lupus del Sistema Nervioso Central/tratamiento farmacológico , Vasculitis por Lupus del Sistema Nervioso Central/epidemiología , Vasculitis por Lupus del Sistema Nervioso Central/mortalidad , Masculino , Prednisona/efectos adversos , Prednisona/uso terapéutico , Pronóstico , Pubertad , Medición de Riesgo/métodos , Estadísticas no Paramétricas , Factores de Tiempo , Resultado del Tratamiento
14.
Foods ; 8(6)2019 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-31181692

RESUMEN

The beef cattle industry is facing multiple problems, from the unequal distribution of added value to the poor matching of its product with fast-changing demand. Therefore, the aim of this study was to examine the interactions between the main variables, evaluating the nutritional and organoleptic properties of meat and cattle performances, including carcass properties, to assess a new method of managing the trade-off between these four performance goals. For this purpose, each variable evaluating the parameters of interest has been statistically modeled and based on data collected on 30 Blonde d'Aquitaine heifers. The variables were obtained after a statistical pre-treatment (clustering of variables) to reduce the redundancy of the 62 initial variables. The sensitivity analysis evaluated the importance of each independent variable in the models, and a graphical approach completed the analysis of the relationships between the variables. Then, the models were used to generate virtual animals and study the relationships between the nutritional and organoleptic quality. No apparent link between the nutritional and organoleptic properties of meat (r = -0.17) was established, indicating that no important trade-off between these two qualities was needed. The 30 best and worst profiles were selected based on nutritional and organoleptic expectations set by a group of experts from the INRA (French National Institute for Agricultural Research) and Institut de l'Elevage (French Livestock Institute). The comparison between the two extreme profiles showed that heavier and fatter carcasses led to low nutritional and organoleptic quality.

15.
Cancer Rep (Hoboken) ; 2(5): e1186, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-32721109

RESUMEN

BACKGROUND: Bridged silsesquioxane nanoparticles (BSNs) recently described represent a new class of nanoparticles exhibiting versatile applications and particularly a strong potential for nanomedicine. AIMS: In this work, we describe the synthesis of BSNs from an octasilylated functional porphyrin precursor (PORBSNs) efficiently obtained through a click reaction. These innovative and very small-sized nanoparticles were functionalized with PEG and mannose (PORBSNs-mannose) in order to target breast tumors in vivo. METHODS AND RESULTS: The structure of these nanoparticles is constituted of porphyrins J aggregates that allow two-photon spatiotemporal excitation of the nanoparticles. The therapeutic potential of such photoactivable nanoparticles was first studied in vitro, in human breast cancer cells in culture and then in vivo on zebrafish embryos bearing human tumors. These animal models were intravenously injected with 5 nL of a solution containing PORBSNs-mannose. An hour and half after the injection of photoactivable and targeted nanoparticles, the tumor areas were excited for few seconds with a two-photon beam induced focused laser. We observed strong tumor size decrease, with the involvement of apoptosis pathway activation. CONCLUSION: We demonstrated the high targeting, imaging, and therapeutic potential of PORBSNs-mannose injected in the blood stream of zebrafish xenografted with human tumors.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Nanopartículas/administración & dosificación , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/administración & dosificación , Nanomedicina Teranóstica/métodos , Animales , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Humanos , Inyecciones Intravenosas , Rayos Láser , Microscopía de Fluorescencia por Excitación Multifotónica , Nanopartículas/química , Nanopartículas/efectos de la radiación , Fotoquimioterapia/instrumentación , Fármacos Fotosensibilizantes/química , Porfirinas/administración & dosificación , Porfirinas/química , Silanos/administración & dosificación , Silanos/química , Nanomedicina Teranóstica/instrumentación , Ensayos Antitumor por Modelo de Xenoinjerto , Pez Cebra
16.
Eur J Pharm Biopharm ; 68(2): 319-29, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17540546

RESUMEN

We reported the physical chemical characterization of a new series of native dextran (B110-1-2). The chemical structure of the polymer was characterized by IR, (1)H and (13)C NMR spectroscopy and compared with that of a commercial native dextran B512-F obtained from Sigma Company. Molecular weights of the product and different commercial dextran fractions of Leuconostoc mesenteroides from 43000 to 170000 average molecular weight (M(w)) were established by the analysis of intrinsic viscosity in aqueous solutions and compared with those obtained by gel permeation chromatography (GPC). The critical overlap concentration around 9g/L was obtained. No interactions of powder mixtures with different commercial excipients (lactose, cetyl alcohol, HPMC) and drugs (propranolol hydrochloride, acetyl salicyclic acid, isosorbide dinitrate, lobenzarit disodium, and nifedipine) were demonstrated by differential scanning calorimetry (DSC) analysis. Tablets obtained by direct compression showed good physical-mechanical and technological properties. Dextran B110-1-2 has similar physical chemical properties as commercial Sigma B512-F. Water uptake, erosion and dissolution profile studies for dextran tablets established that glucose polymer with molecular weight M(w) > or = 2x10(6) is suitable for the development of controlled release solid dosage forms (soluble drugs). Fraction of dextran (M(w) 40000-170000) could be more useful for immediate release tablets.


Asunto(s)
Dextranos/administración & dosificación , Excipientes , Preparaciones Farmacéuticas , Saccharum/química , Comprimidos , Espectroscopía de Resonancia Magnética , Espectrofotometría Infrarroja , Viscosidad
17.
Artículo en Inglés | MEDLINE | ID: mdl-18687407

RESUMEN

There are genetic differences in the hepatic glucose and linoleic acid metabolisms between Muscovy and Pekin ducks ad libitum-fed. To understand the effect of overfeeding on the hepatic metabolisms in these two species of ducks, we compared the different pathways of glucose and linoleic acid reaching the liver of Muscovy (Cairina moschata) (n=6) and Pekin (Anas platyrhynchos) (n=6) ducks overfed for 1 week and sacrificed 2-4 h after their last meal by using the ex vivo method of liver slices incubated for 16 h with [U-(14)C]-glucose, [1-(14)C]-linoleic acid and [(35)S]-methionine added to the survival medium. The glucose was the main precursor of triacylglycerol synthesis in the liver of these two species and its hepatic metabolism was similar between species. The hepatic uptake of linoleic acid was 1.7-fold higher (P=0.020) in the Muscovy duck than in the Pekin duck leading to a 1.9-fold higher (P=0.017) esterification of this fatty acid in the liver of the Muscovy duck than in that of the Pekin duck. Finally, both species after 1 week of overfeeding exhibited the same capacity to secrete VLDL remaining insufficient to avoid hepatic steatosis.


Asunto(s)
Patos/metabolismo , Glucosa/metabolismo , Ácido Linoleico/metabolismo , Hígado/metabolismo , Animales , Patos/clasificación , Patos/crecimiento & desarrollo , Ingestión de Alimentos , Hígado Graso/etiología , Hígado Graso/metabolismo , Técnicas In Vitro , Lipoproteínas VLDL/metabolismo , Masculino , Metionina/metabolismo , Especificidad de la Especie
18.
Drug Dev Ind Pharm ; 34(5): 485-91, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18473230

RESUMEN

A study to enhance the dissolution rate of ibuprofen, a poorly water-soluble drug, was carried out through combining specific formulations and processes with the addition of a hydrophilic carrier for the preparation of microparticles. Microparticle production was performed by spray drying ibuprofen microsuspensions formulated in an aqueous system with the addition of ethanol containing Aerosil 200 and Tween 80. We were able to consistently produce microparticles as much as 40% of the dry weight of the input microsuspension. Spray-dried microparticles were characterized by scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, laser diffractometer mastersizer, and infrared spectroscopy. No modification to the crystalinity and chemical structure of ibuprofen was observed. Dissolution of ibuprofen microparticles reached 100% in 3 minutes compared with less than 10% for unmodified ibuprofen. We concluded that both by the modification of formulation and the spray drying process it is possible to increase the dissolution rate of the tested model drug.


Asunto(s)
Antiinflamatorios no Esteroideos/química , Ibuprofeno/química , Rastreo Diferencial de Calorimetría , Fenómenos Químicos , Química Física , Portadores de Fármacos , Estabilidad de Medicamentos , Etanol/química , Liofilización , Cinética , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Polisorbatos/química , Dióxido de Silicio/química , Solubilidad , Espectrofotometría Infrarroja , Agua , Difracción de Rayos X
19.
Data Brief ; 21: 2496-2503, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30761329

RESUMEN

This data article reports the values of indicators of bovine health determined in the plasma of Normand cull-cows at different times of the about 100 days lasting finishing period and at slaughter. The data constitute a large dataset based on the quantification of metabolites and the evaluation of enzymes activities allowing the determination of antioxidant capacity, oxidative stress level, energy and lipid metabolisms, activity of the Hypothalamo-Pituitary-Adrenal axis and the hepatic status in cull-cows.

20.
Cancer Prev Res (Phila) ; 11(9): 569-580, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29954759

RESUMEN

Red meat is probably carcinogenic to humans (WHO/IARC class 2A), in part through heme iron-induced lipoperoxidation. Here, we investigated whether red meat promotes carcinogenesis in rodents and modulates associated biomarkers in volunteers, speculating that an antioxidant marinade could suppress these effects via limitation of the heme induced lipid peroxidation. We gave marinated or non-marinated beef with various degrees of cooking to azoxymethane-initiated rats, Min mice, and human volunteers (crossover study). Mucin-depleted foci were scored in rats, adenoma in Min mice. Biomarkers of lipoperoxidation were measured in the feces and urine of rats, mice, and volunteers. The organoleptic properties of marinated meat were tested. Fresh beef increased colon carcinogenesis and lipoperoxidation in rats and mice and lipoperoxidation in humans. Without an adverse organoleptic effect on meat, marinade normalized peroxidation biomarkers in rat and mouse feces, reduced peroxidation in human feces and reduced the number of Mucin-depleted foci in rats and adenoma in female Min mice. This could lead to protective strategies to decrease the colorectal cancer burden associated with red meat consumption. Cancer Prev Res; 11(9); 569-80. ©2018 AACR.


Asunto(s)
Carcinogénesis/patología , Neoplasias del Colon/prevención & control , Culinaria , Peroxidación de Lípido/fisiología , Carne Roja/efectos adversos , Adulto , Animales , Azoximetano/administración & dosificación , Azoximetano/toxicidad , Biomarcadores/análisis , Carcinógenos/administración & dosificación , Neoplasias del Colon/etiología , Estudios Cruzados , Heces/química , Femenino , Voluntarios Sanos , Hemo/metabolismo , Humanos , Masculino , Ratones , Persona de Mediana Edad , Neoplasias Experimentales/inducido químicamente , Neoplasias Experimentales/prevención & control , Ratas , Ratas Endogámicas F344
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