Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 13 de 13
Filter
1.
Int J Pharm ; 586: 119533, 2020 Aug 30.
Article in English | MEDLINE | ID: mdl-32534160

ABSTRACT

Current efforts on inflammatory bowel diseases (IBD) treatment are focused on strategies for localised drug delivery at the intestinal mucosa. Despite the potential of curcumin (CC) for IBD treatment, its low solubility and stability limit its application. Thus, the design of nanocarriers that focus CC delivery at the intestinal epithelium is an area of interest. This work proposes α-tocopherol nanoemulsions (NE) stabilised by ascorbyl-2,6-dipalmitate (ADP) as intestinal CC-carriers. The antioxidant capacity of α-tocopherol and ADP could have a synergistic effect on IBD-affected tissues, characterised by an oxidative environment. We obtained nanoemulsions (NE-ADP) with size below 200 nm, negative surface charge, stable in gastrointestinal media and no toxic in the Caco-2 cell model. Intracellular retention of NE-ADP in Caco-2 cells was observed by confocal microscopy. The extremely low Papp values obtained for CC and α-tocopherol indicated the lack of transport across the Caco-2 monolayer. Control nanoemulsion stabilised by lecithin (NE-L) was greatly transported across the Caco-2 cells monolayer, confirming the relevance of ADP on the cellular retention of NE-ADP. The therapeutic potential of NE-ADP was shown by the significant decrease of intracellular ROS levels. Altogether, these results indicate the potential of NE-ADP as a novel approach for the treatment of IBD.


Subject(s)
Ascorbic Acid/chemistry , Curcumin/administration & dosage , Inflammatory Bowel Diseases/drug therapy , Palmitates/chemistry , alpha-Tocopherol/administration & dosage , Antioxidants/administration & dosage , Antioxidants/pharmacology , Biological Transport , Caco-2 Cells , Curcumin/pharmacology , Drug Carriers/chemistry , Drug Delivery Systems , Emulsions , Humans , Lecithins/chemistry , Nanoparticles , Particle Size , Reactive Oxygen Species/metabolism , Solubility , alpha-Tocopherol/pharmacology
2.
Benef Microbes ; 10(5): 579-587, 2019 May 28.
Article in English | MEDLINE | ID: mdl-31122043

ABSTRACT

γ-Aminobutyric acid (GABA), an amino acid not used in protein synthesis, intervenes in several physiological functions and has both diuretic and calming effects in humans. Lactic acid bacteria (LAB) strains that produce GABA could be exploited for the manufacture of health-promoting GABA-enriched dairy products. In this study, 262 LAB strains isolated from traditional dairy products made from raw milk without starter cultures were screened for GABA production in culture media supplemented with 1% monosodium glutamate (MSG) using an enzymatic (GABase) method. About half of the strains (123) were found to be GABA producers. Of these, 24, among which were 16 Lactococcus lactis subsp. lactis and three Streptococcus thermophilus strains, produced >1 mM of GABA (range 1.01-2.81 mM) and were selected for further characterisation. GABA production was confirmed in most strains by culturing in 5 mM MSG followed by HPLC quantification. A majority of the strains were confirmed to be GABA producers by this method, although lower production levels were recorded. Using species-specific primers, the gene encoding glutamate decarboxylase (GAD) was PCR-amplified in all but one of the GABA producers analysed. Amplicons sequences were compared to one another and to those held in databases. Except for one Lactobacillus brevis strain, none of the 24 GABA producers investigated produced toxic biogenic amines, such as tyramine, histamine or cadaverine. They were therefore considered safe. Either alone, in mixtures, or in combination with industrial starter or adjunct cultures, these strains might be useful in the development of health-oriented dairy products.


Subject(s)
Cultured Milk Products/microbiology , GABA Agents/metabolism , Lactobacillales/isolation & purification , Lactobacillales/metabolism , gamma-Aminobutyric Acid/metabolism , Bacteriological Techniques , Chromatography, High Pressure Liquid , Glutamate Decarboxylase/genetics , Lactobacillales/classification , Lactobacillales/enzymology , Polymerase Chain Reaction
3.
J Anat ; 232(4): 699-715, 2018 04.
Article in English | MEDLINE | ID: mdl-29315537

ABSTRACT

Its high metabolic rate and high polyunsaturated fatty acid content make the brain very sensitive to oxidative damage. In the brain, neuronal metabolism occurs at a very high rate and generates considerable amounts of reactive oxygen species and free radicals, which accumulate inside neurons, leading to altered cellular homeostasis and integrity and eventually irreversible damage and cell death. A misbalance in redox metabolism and the subsequent neurodegeneration increase throughout the course of normal aging, leading to several age-related changes in learning and memory as well as motor functions. The neuroprotective function of antioxidants is crucial to maintain good brain homeostasis and adequate neuronal functions. Vitamins E and C are two important antioxidants that are taken up by brain cells via the specific carriers αTTP and SVCT2, respectively. The aim of this study was to use immunohistochemistry to determine the distribution pattern of these vitamin transporters in the brain in a mouse model that shows fewer signs of brain aging and a higher resistance to oxidative damage. Both carriers were distributed widely throughout the entire brain in a pattern that remained similar in 4-, 12-, 18- and 24-month-old mice. In general, αTTP and SVCT2 were located in the same regions, but they seemed to have complementary distribution patterns. Double-labeled cell bodies were detected only in the inferior colliculus, entorhinal cortex, dorsal subiculum, and several cortical areas. In addition, the presence of αTTP and SVCT2 in neurons was analyzed using double immunohistochemistry for NeuN and the results showed that αTTP but not SVCT2 was present in Bergmann's glia. The presence of these transporters in brain regions implicated in learning, memory and motor control provides an anatomical basis that may explain the higher resistance of this animal model to brain oxidative stress, which is associated with better motor performance and learning abilities in old age.


Subject(s)
Aging/metabolism , Brain/metabolism , Carrier Proteins/metabolism , Oxidative Stress , Sodium-Coupled Vitamin C Transporters/metabolism , Animals , Antigens, Nuclear/metabolism , Antioxidants/metabolism , Ascorbic Acid/metabolism , Biomarkers/metabolism , Brain/diagnostic imaging , Glial Fibrillary Acidic Protein/metabolism , Immunohistochemistry/methods , Learning , Male , Memory , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout , Nerve Tissue Proteins/metabolism , Neuroglia/metabolism , Neuroglia/ultrastructure , Neurons/metabolism , Neurons/ultrastructure , Vitamin E/metabolism
4.
Langmuir ; 33(17): 4269-4279, 2017 05 02.
Article in English | MEDLINE | ID: mdl-28391698

ABSTRACT

Since the past decade, there has been growing interest to grant nanoparticles with diffusion properties across mucosae. In this sense, the nonionic block copolymer Pluronic F127 (PF127) has emerged as a promising coating agent to formulate mucus-penetrating particles. In the journey to find efficient coating agents, researchers have focused more on the effect of the coating agent architecture rather than on the role of the physicochemical properties of the nanoparticle used as the substrate. The current knowledge about mucodiffusive particles is in general based on model-like nanoparticles, such as polystyrene or poly(lactic-co-glycolic) acid nanoparticles, but there is a lack of information about the potential of PF127 on other colloidal systems. This work aims to shed some light on this issue by selecting three oils, palm (solid), coconut (semisolid), and wheat germ (liquid), with different physicochemical properties to formulate PF127-coated nanoemulsions. The obtained nanoemulsions were characterized, and their colloidal stability was tested. Their diffusion capacity was determined by particle tracking after challenging the nanoemulsions across an intestinal porcine mucus layer. In accordance with the evidence of model-like nanoparticles, our results state that PF127 allows mucodiffusion, but its effectiveness as a coating agent clearly depends on the physicochemical properties of the nanostructure core over which PF127 is placed. Among other physicochemical properties, the results certainly showed that the hydrophobic character of the nanostructure core emerges as a critical factor in the formulation of successful PF127 coatings.


Subject(s)
Emulsions/chemistry , Excipients/chemistry , Nanoparticles/chemistry , Poloxamer/chemistry , Surface-Active Agents/chemistry , Administration, Oral , Animals , Coconut Oil/chemistry , Diffusion , Drug Stability , Hydrogen-Ion Concentration , Hydrophobic and Hydrophilic Interactions , Mucus/chemistry , Palm Oil/chemistry , Pancreatin/chemistry , Particle Size , Pepsin A/chemistry , Plant Oils/chemistry , Swine , alpha-Tocopherol/chemistry
5.
J Anim Physiol Anim Nutr (Berl) ; 101(4): 723-732, 2017 Aug.
Article in English | MEDLINE | ID: mdl-27121753

ABSTRACT

The dietary contents of crude protein and free amino acids (AA) may affect the protein digestion and AA absorption in pigs. Trypsin and chymotrypsin activities, AA serum concentrations and expression of AA transporters in the small intestine of pigs fed a low protein, AA-supplemented (19.2%, LPAA) or a high protein (28.1%, HP), wheat-soybean meal diet were measured in two 14-d trials. The LPAA diet contained free L-Lys, L-Thr, DL-Met, L-Leu, L-Ile, L-Val, L-His, L-Trp and L-Phe. All pigs were fed the same amount of feed (890 and 800 g/d for trial 1 and 2 respectively). In trial 1, samples of mucosa (duodenum, jejunum and ileum) and digesta (duodenum and jejunum) were collected from 14 pigs (17.2 ± 0.4 kg); in trial 2, blood samples were collected from 12 pigs (12.7 ± 0.3 kg). The trypsin and chymotrypsin activities in both intestinal segments were higher in pigs fed the HP diet (p < 0.01). Trypsin activity was higher in jejunum than in duodenum regardless the dietary treatment (p < 0.05). Pigs fed the LPAA diet expressed more b0,+ AT in duodenum, B0 AT1 in ileum (p < 0.05), and tended to express more y+ LAT1 in duodenum (p = 0.10). In pigs fed the LPAA diet, the expression of b0,+ AT was higher in duodenum than in jejunum and ileum (p < 0.01), but no difference was observed in pigs fed the HP diet. Ileum had the lowest b0,+ AT expression regardless the diet. The serum concentrations of Lys, Thr and Met were higher in LPAA pigs while serum Arg was higher in HP pigs (p < 0.05). Serum concentrations of AA appear to reflect the AA absorption. In conclusion, these data indicate that the dietary protein contents affect the extent of protein digestion and that supplemental free AA may influence the intestinal site of AA release and absorption, which may impact their availability for growth of young pigs.


Subject(s)
Amino Acids/pharmacology , Animal Feed/analysis , Dietary Proteins/pharmacology , Pancreas/enzymology , Peptide Hydrolases/metabolism , Swine/physiology , Amino Acid Transport Systems/metabolism , Amino Acids/blood , Animal Nutritional Physiological Phenomena , Animals , Diet/veterinary , Gene Expression Regulation/drug effects , Peptide Hydrolases/genetics
6.
Food Chem ; 197(Pt A): 509-15, 2016 Apr 15.
Article in English | MEDLINE | ID: mdl-26616982

ABSTRACT

This work is about improvement of a maceration method in order to achieve a green process for the enrichment of virgin olive oil (VOO) with natural antioxidants, specifically from oregano leaves. This goal was accomplished after evaluating different mechanical methods, i.e. magnetic stirring, sonication, vertical stirring and sonication in combination with vertical stirring, for promoting the extraction of the antioxidants from oregano. The results obtained indicated that the best extraction procedure was vertical stirring at 1000 r.p.m. for 3 h. Therefore, these conditions were selected to enrich VOO with phenolic acids (mainly rosmarinic acid) and endogenous antioxidants (o-coumaric and vanillic acids), and further determine their stability at room temperature or under temperature stress (50°C) during 45 days. Quantitative analysis of rosmarinic, o-coumaric and vanillic acids was carried out by an off-line, solid phase extraction, capillary zone, electrophoresis method combined with diode-array detector (SPE-CE-DAD).


Subject(s)
Antioxidants/analysis , Food Additives/analysis , Olive Oil/chemistry , Origanum/chemistry , Plant Extracts/analysis , Cinnamates/analysis , Depsides/analysis , Hydroxybenzoates/analysis , Plant Leaves/chemistry , Rosmarinic Acid
7.
Int J Pharm ; 490(1-2): 209-18, 2015 Jul 25.
Article in English | MEDLINE | ID: mdl-25997659

ABSTRACT

Most frequently the use of bioactive molecules for the supplementation of food and beverages is hampered by stability limitations or inadequate intestinal absorption. This work evaluates in vitro the role that the interface of the nanoemulsion has on the physicochemical properties, the stability behavior and the enzymatic degradation after oral intake. For that purpose three soybean oil (SB) formulations were studied. These formulations were based on the emulsifier lecithin but modified with two non-ionic surfactants Pluronic(®) F68 (PF68) or Pluronic(®) F127 (PF127) yielding (i) SB-NE (only lecithin on the interface), (ii) SB-NE PF68 (lecithin plus PF68) and 9 (iii) SB-NE PF127 (lecithin plus PF127). All the formulations tested were low polydispersed and showed a size of about 200 nm and ζ-potential of -50 mV. The in vitro colloidal stability assay showed that lecithin itself was able to promote that formulations reach unaltered to the small intestine and facilitate the absorption of the antioxidant payload on a tunable fashion there (with in vitro bioaccessibility values from around 40% up to a 70%). PF68 was able to sterically stabilize the formulation against the aggregation induced by the pH and electrolytes of the simulated gastrointestinal track; however, this surfactant was easily displaced by the lipases of the simulated intestinal milieu being unable to modulate the digestion pattern of the oil droplets in the small intestine. Finally, PF127 displayed a strong steric potential that dramatically reduced the interaction of the oil droplets with lipases in vitro, which will compromise the capacity of the formulation to improve the bioaccessibility of the loaded antioxidant.


Subject(s)
Antioxidants/chemistry , Emulsions/chemistry , Nanoparticles/chemistry , Neuroprotective Agents/chemistry , Biological Availability , Chemistry, Pharmaceutical/methods , Drug Carriers/chemistry , Emulsifying Agents/chemistry , Lecithins/chemistry , Particle Size , Soybean Oil/chemistry
8.
Phys Rev Lett ; 112(9): 094103, 2014 Mar 07.
Article in English | MEDLINE | ID: mdl-24655256

ABSTRACT

We report the experimental observation of a submicron cellular structure on the surface of silicon targets eroded by an ion plasma. Analysis by atomic force microscopy allows us to assess the time evolution and show that the system can be described quantitatively by the convective Cahn-Hilliard equation, found in the study of domain coarsening for a large class of driven systems. The space-filling trait of the ensuing pattern relates it to evolving foams. Through this connection, we are actually able to derive the coarsening law for the pattern wavelength from the nontrivial topological dynamics of the cellular structure. Thus, the study of the topological properties of patterns in nonvariational spatially extended systems emerges as complementary to morphological approaches to their challenging coarsening properties.

10.
Int J Biometeorol ; 49(3): 184-8, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15645246

ABSTRACT

Olives are one of the largest crops in the Mediterranean region, especially in Andalusia, in southern Spain. A thermal model has been developed for forecasting the start of the olive tree pollen season at five localities in Andalusia: Cordoba, Priego, Jaen, Granada and Malaga using airborne pollen and meteorological data from 1982 to 2001. Threshold temperatures varied between 5 degrees C and 12.5 degrees C depending on bio-geographical characteristics. The external validity of the results was tested using the data for the year 2002 as an independent variable and it confirmed the model's accuracy with only a few days difference from predicted values. All the localities had increasingly earlier start dates during the study period. This could confirm that olive flower phenology can be considered as a sensitive indicator of the effects of climate fluctuations in the Mediterranean area. The theoretical impact of the predicted climatic warming on the olive's flowering phenology at the end of the century is also proposed by applying Regional Climate Model data. A general advance, from 1 to 3 weeks could be expected, although this advance will be more pronounced in mid-altitude inland areas.


Subject(s)
Climate , Olea , Pollen , Greenhouse Effect , Hot Temperature , Olea/growth & development , Seasons , Spain
11.
Int J Biometeorol ; 48(2): 83-90, 2003 Dec.
Article in English | MEDLINE | ID: mdl-12925873

ABSTRACT

The influence of meteorological parameters on the dispersion of airborne pollen has been studied by several authors. Olive pollen is the major cause of allergy in southern Spain, where a large part of the arable surface area is given over to olive cultivation. Daily pollen forecasts provide important information both for pollen-allergy sufferers and for agronomists trying to achieve a better biological understanding of variations in airborne olive pollen levels. The main purpose of this paper is to study, by means of short-term statistical analysis, the effect of meteorological parameters on airborne olive pollen concentrations in the city of Cordoba (south-western Spain). Twenty-one-year (1982-2002) aerobiological and meteorological databases were used. Correlation and multiple regression analyses were used to study the relationships between olive pollen levels and several meteorological parameters. Statistical analysis was applied both to the whole pollen season and to the pre-peak period. Daily meteorological parameters, such as accumulated mean temperature, accumulated sunlight hours, and accumulated rainfall were used as independent variables in both statistical analyses. Accumulated meteorological variables were of the greatest value in most regression analysis equations, heat-related variables being the most important.


Subject(s)
Olea , Pollen , Forecasting , Humans , Meteorological Concepts , Regression Analysis , Rhinitis, Allergic, Seasonal/etiology , Rhinitis, Allergic, Seasonal/prevention & control , Spain
12.
Hematol Cell Ther ; 39(5): 223-7, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9395895

ABSTRACT

The objective of this study was to determine the efficacy and safety of the combination ciprofloxacin plus amoxicillin/clavulanic acid as an empirical treatment of infection in hematologic patients without severe neutropenia. These drugs allowed us to carry out a sequential therapy, first intravenously and later orally, so that the patient could be discharged as soon as there was a response. Serum concentrations of ciprofloxacin were monitored in this study. Forty seven of the sixty-six patients included (71%) responded to the treatment with no differences between the dosages of ciprofloxacin employed (600-900 mg daily in two or three divided doses). In the patients who responded, the signs and symptoms of infection lasted only three days, which could allow a short hospital stay (median of six days). In the first pre and post-dose serum samples, ciprofloxacin concentrations were significantly higher when the drug was administered every 8 h. Nevertheless, 72 h after the beginning of treatment, they had leveled out in either 8 and 12 h schemes. The toxicity of the treatment was very light, with only four cases with adverse effects, grades I and II. This data suggests that the employed combination is effective and safe and can considerably decrease costs incurred through the admission of hematologic patients with serious infections but without severe neutropenia.


Subject(s)
Bacterial Infections/drug therapy , Drug Therapy, Combination/therapeutic use , Length of Stay , Neutropenia/complications , Administration, Oral , Adolescent , Adult , Aged , Aged, 80 and over , Amoxicillin/administration & dosage , Amoxicillin/therapeutic use , Analysis of Variance , Bacterial Infections/complications , Ciprofloxacin/adverse effects , Ciprofloxacin/therapeutic use , Clavulanic Acid/administration & dosage , Clavulanic Acid/therapeutic use , Drug Administration Schedule , Drug Therapy, Combination/adverse effects , Female , Humans , Male , Middle Aged , Risk Factors , Treatment Outcome
13.
Rev Biol Trop ; 44-45: 143-8, 1997 Mar.
Article in Spanish | MEDLINE | ID: mdl-9404518

ABSTRACT

The sweet potato white fly, Bemisia tabaci, is an important pest of tomatoes and beans, among other crops, which transmits viral diseases. Since the second quarter of 1989 a significant population increase of this pest has been noted in several cultivated plants. From 1989 to 1992, a survey was done throughout the country, chiefly in vegetable and bean-producing areas. They occur in 119 species (42 families), a great increase over the previous record of four species. Worldwide, this report represents 50 species and six families which are new records.


Subject(s)
Host-Parasite Interactions , Insecta/pathogenicity , Plants/parasitology , Animals , Cuba , Fabaceae/parasitology , Fabaceae/virology , Solanum lycopersicum/parasitology , Solanum lycopersicum/virology , Plants, Medicinal
SELECTION OF CITATIONS
SEARCH DETAIL