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M L Rodríguez

Publications and source records attributed to M L Rodríguez.

At least 19 recordsLinked to original sources
PubMed2006

Effect of dietary high-oleic acid sunflower seed, palm oil and vitamin E supplementation on broiler performance, fatty acid composition and oxidation susceptibility of meat.

1. A study was conducted to evaluate the effect of inclusion of two fat sources: high-oleic acid sunflower seed (HOASS; 0, 50, 100, 150 and 200 g/kg diet) and palm oil (PO), and dietary supplementation of vitamin E (alpha-tocopheryl acetate, 200 mg/kg diet) on performance, fatty acid composition and susceptibility to oxidation of white and dark chicken meat during refrigerated storage. Female chicks (3 to 6 weeks) were given one of 5 diets containing 90 g/kg of added fat with increasing monounsaturated fatty acid (MUFA) content, adjusted by progressively replacing PO by HOASS. 2. Body weight gain and gain:food ratio of birds were depressed in diets containing the highest proportions of HOASS (150 and 200 g/kg). Relative abdominal fat was reduced in birds fed diets including HOASS, except in the diet containing 100 g HOASS/kg. The inclusion of alpha-tocopheryl acetate improved body weight gain and gain:food ratio. 3. According to the fatty acid profile of the diets, saturated and polyunsaturated fatty acid (SFA and PUFA, respectively) contents were significantly reduced and MUFA content was significantly increased in white and dark chicken meats when the saturated oil, PO, was replaced progressively by HOASS in the diet. The inclusion of alpha-tocopheryl acetate increased PUFA content in both meats. 4. After 4 and 7 d of refrigerated storage, white and dark meat samples obtained from birds fed on diets containing HOASS had significantly lower thiobarbituric acid reacting substance (TBARS) values than those derived from the PO diet. The addition of alpha-tocopheryl acetate significantly reduced the lipid oxidation in white and dark meat. 5. Overall, the results showed that increasing MUFA content of chicken meat by replacing dietary PO with HOASS (up to 100 g/kg) did not adversely affect broiler performance and reduced the susceptibility of meat to oxidation during refrigerated storage. Dietary alpha-tocopherol supplementation improved chicken performance and was effective in protecting lipid meat from oxidation.

Animal Feed↗
PubMed2005

Supramolecular aggregation of two hydroxycarboxylic acid derivatives.

The crystal structures of 7,7-dicyclobutyl-5-hydroxymethyl-6-oxabicyclo[3.2.1]octane-1-carboxylic acid, C17H26O4, (I), and 1-(hydroxymethyl)-7-oxaspiro[bicyclo[3.2.1]octane-6,1'-cyclopentane]-5-carboxylic acid, C13H20O4, (II), determined at 170 K, show that the conformation of the hydroxymethyl group (anti or gauche) affects the dimensionality (one- or two-dimensional) of the supramolecular structures via O-H...O hydrogen bonds. In (I), the carboxyl and hydroxymethyl groups interact with themselves, forming a one-dimensional step-ladder, while in (II), a two-dimensional structure is made up of carboxylic acid centrosymmetric R(2)2(8) dimers connected by hydroxyl-to-ether contacts.

Journal Article↗
PubMed2005

Hydrogen-bonding patterns of two dihydroxylactone derivatives.

In the hydrogen-bonding networks of 8-hydroxy-5-hydroxymethyl-3,6-dioxatricyclo[6.3.1.0(1.5)]dodecan-2-one and 5,7-bis(hydroxymethyl)-3,6-dioxatricyclo[5.3.1.0(1.5)]undecan-2-one, both C11H16O5, layers and double strands, respectively, lead to the formation of chains connected by hydroxy-to-hydroxy contacts, where the hydroxymethyl group, present in both structures, acts as a donor. The secondary structures differ in the hydrogen bonding of these chains via the second hydroxy group, which is involved in hydroxy-to-carbonyl and hydroxy-to-hydroxy bonds, respectively.

Journal Article↗
PubMed2005

Nutritive value of high-oleic acid sunflower seed for broiler chickens.

Two experiments were conducted to evaluate the use of high-oleic acid sunflower seed (HOASS) in broiler diets. In the first experiment, HOASS was included in a basal diet at 80, 160, 240, and 320 g/kg at the expense of the energy-yielding ingredients, and the AMEn values of the experimental diets were determined. The linear regression equation of AMEn values on rate of inclusion was calculated. Extrapolation value for the AMEn of HOASS at 100% inclusion was 4224 +/- 77 kcal/kg. In the second experiment, diets containing up to 200 g of HOASS/kg were given to broilers (Cobb) from 0 to 42 d, and performance parameters, nutrient digestibility, and AMEn value were determined at 12 and 42 d of age. Birds fed the diets containing 100 and 200 g HOASS/kg gained less weight (P < 0.001) than those fed the diet containing no HOASS at both ages. Differences in feed-to-gain ratio were only significant for the diet with the highest concentration of HOASS. Apparent digestibility of nutrients and dietary AMEn contents of diets increased with age; thus, the mean digestibility of diets for amino acid N and for total fatty acids increased from 82.1 and 68.0% at 12 d to 86.7 and 84.7% at 42 d, respectively, and AMEn content was improved by 6.5%. Inclusion of HOASS in the diet decreased the digestibilities of fat, oleic acid, and total fatty acids. A decrease in the digestibility of aspartic acid, threonine, tyrosine, valine, isoleucine, and AMEn with increasing inclusion level was also observed at 12 d of age.

Aging↗
PubMed2004

The photon fluence non-uniformity correction for air kerma near Cs-137 brachytherapy sources.

The use of brachytherapy sources in radiation oncology requires their proper calibration to guarantee the correctness of the dose delivered to the treatment volume of a patient. One of the elements to take into account in the dose calculation formalism is the non-uniformity of the photon fluence due to the beam divergence that causes a steep dose gradient near the source. The correction factors for this phenomenon have been usually evaluated by the two theories available, both of which were conceived only for point sources. This work presents the Monte Carlo assessment of the non-uniformity correction factors for a Cs-137 linear source and a Farmer-type ionization chamber. The results have clearly demonstrated that for linear sources there are some important differences among the values obtained from different calculation models, especially at short distances from the source. The use of experimental values for each specific source geometry is recommended in order to assess the non-uniformity factors for linear sources in clinical situations that require special dose calculations or when the correctness of treatment planning software is verified during the acceptance tests.

Air↗
PubMed2003

Effect of whole and demucilaged linseed in broiler chicken diets on digesta viscosity, nutrient utilisation and intestinal microflora.

1. A study was undertaken to evaluate the effects of the inclusion of linseed or demucilaged linseed in the diet on the performance, fat and fatty acid digestibilities, metabolisability of gross energy and intestinal microflora. 2. The dietary inclusions were 80 and 160 g/kg for linseed and 160 g/kg for demucilaged linseed. Diets were given to chickens from 1 to 23 d of age. 3. Incorporation of linseed in the diet, particularly at 160 g/kg, depressed weight gain and food utilisation. Digestibility of fat and single fatty acids and dietary metabolisable energy were reduced. 4. Inclusion of linseed in the diet markedly increased the viscosity of ileal digesta. Microbial activity in the ileum and caeca was not greatly affected, but there was a significant increase in the number of lactobacilli. 5. The antinutritional effects caused by feeding linseed were partially overcome by substituting demucilaged linseed for linseed in the diet. 6. Results from the current study suggest that the viscous properties of mucilage are a major factor in the observed antinutritional effects of linseed through increasing intestinal viscosity. Such effects might also be mediated by the gut microflora.

Animal Feed↗
PubMed2001

Tubular hydrogen-bonded networks sustained by water molecules.

The design concept of functional solids relies on controlling the topology of crystal packing through exploitation of weak intermolecular forces. In the context of cyclic aggregates, the ability to anticipate the consequences of ring constituents and their stereochemistries on ring conformation is vitally important since even an apparently slight structural change effected on molecules can dramatically alter the crystal structure. We have found that solid-state structures formed by hydroxy acids with a general structure (+/-)-1 depend on steric interactions. Thus, with the exception of molecules 1b and 1e, compounds (+/-)-1a-(+/-)-1m, which possess bulky and conformationally rigid substituents, aggregate by forming tapes and sheets by alternating (+) and (-) subunits held together through carboxylic acid-to-alcohol hydrogen bonds. Homologue (+/-)-1n, with conformationally flexible substituents which allow conformational deformation, gives, by incorporation of molecules of water, an efficient hexagonal assembly which extends to the third dimension to form tubular H-bonding networks. Each puckered channel can be described as interconnected closely packed hexagons in chairlike conformations. The ethyl groups presented in (+/-)-1n gave the volume required to lock the inner hexagonal wall into a rigid structure. Attempts to obtain cyclic aggregates using small substituents, compounds (+/-)-1o-(+/-)-1q, failed. The observed supramolecular assemblies of the anhydrous compounds can be classified into one-dimensional strands and two-dimensional sheets, while three-dimensional networks are present only in the hydrated molecules (1b, 1e, and 1n). The crystal structure of the anhydrous (+/-)-1n compound confirms the important role played by water molecules in the formation of tubular structures.

Journal Article↗
PubMed2001

Defensive chemistry of Senecio miser.

Three eremophilanolides, 1alpha-acetoxy-8beta-methoxy-10betaH-eremophil-7(11)-en-8alpha,12-olide (1); 1alpha-angeloyloxy-6beta-hydroxy-8beta-methoxy-10betaH-eremophil-7(11)-en-8alpha,12-olide (2); and 1alpha-angeloyloxy-8betaH,10betaH-eremophil-7(11)-en-8alpha,12-olide (3), and two pyrrolizidine alkaloids, integerrimine (4) and its N-oxide (5), were isolated from bioactive fractions of Senecio miser. The structures of the new compounds 1 and 2 were established by NMR spectroscopic analysis and chemical transformation. The X-ray analysis of compound 1 was also performed. Eremophilanolides 1 and 2 and alkaloids 4 and 5 were found to be strong insect antifeedants, further supporting a proposed defensive role for these classes of compounds.

Animals↗
PubMed2001

Effect of inclusion level of linseed on the nutrient utilisation of diets for growing broiler chickens.

1. Diets containing linseed at inclusions of 0, 80, 120 and 160 g/kg were evaluated for digestibility of nutrients and AMEn content with male broiler chickens. 2. Increasing the concentration of linseed decreased the retention of nitrogen and the digestibility of amino acids, crude fat and fatty acids of diets. 3. Dietary AMEn (MJ/kg) was also affected by the rate of inclusion of linseed, values decreasing from 14.39 to 12.49. 4. In general, a linear regression model explained the relationship between dietary linseed content and nutritive parameters. However, the quadratic response found for the digestibility of several amino acids and fatty acids indicated a non-additive change in their digestibility. 5. Viscosity ofjejunal digesta was markedly increased by each increment of linseed in the diets. This is attributable to the presence of mucilage in linseed and it might explain many of the results obtained in this study.

Animal Nutritional Physiological Phenomena↗
PubMed2001

Metabolisable energy value and digestibility of fat and fatty acids in linseed determined with growing broiler chickens.

1. In the first experiment, the AMEN of linseed was evaluated at rates of 40, 80, 160 and 240 g/kg in a basal diet with broiler chickens aged 28 d using the total collection method. 2. Increasing the concentration of linseed decreased the AMEN of diet, from 11.78 to 8.75 MJ/kg DM, and AMEN of linseed, from 16.64 to -2.96 MJ/kg DM. The negative values clearly indicated that linseed interacted with the other dietary ingredients and impaired their energy utilisation. 3. In the second experiment, a semipurified diet with graded addition of linseed (80, 120, 160 and 240 g/kg DM) was evaluated for crude fat and fatty acid apparent digestibilities. The coefficients decreased from 0.602 to 0.359 for crude fat and from 0.661 to 0.352 for individual fatty acids as the level of linseed increased. 4. In both experiments, a quadratic regression model explained the relationship between data better than the linear model. 5. The presence of mucilage and other antinutritional factors in linseed might explain the results obtained in this study.

Animal Nutritional Physiological Phenomena↗
PubMed2001

Efficacy of N-acetylcysteine to reduce the effects of aflatoxin B1 intoxication in broiler chickens.

N-acetylcysteine (NAC) has been used safely in humans and in other mammals as an antidote against several toxic and carcinogenic agents, including aflatoxin B1 (AFB1). The aim of this study was to evaluate the capability of dietary supplementation with NAC to ameliorate the effects of subacute intoxication with AFB1 in broiler chickens. One hundred twenty male Hubbard 1-d-old chickens were allocated into one of four dietary treatments: 1) control group without treatment, 2) purified AFB1 added to diet (3 mg/kg of feed) for 21 d, 3) NAC (800 mg/kg BW, daily), or 4) AFB1 plus NAC at the same doses as Groups 2 and 3. Broilers treated with AFB1 plus NAC were shown to be partially protected against deleterious effects on BW (57.8%), daily weight gain (49.1%), feed conversion index (21.4%), plasma and hepatic total protein concentration (45.2, 66.7%), plasma alanine aminotransferase (67.4%), hepatic glutathione-S-transferase (18.8%), and reduced glutathione liver concentration (75.0%). In addition, they showed less intense liver fading, friable texture, and microvesicular steatosis. In the kidney, thickening of glomerular basement membrane was also less severe in NAC+AFB1-treated chickens than in AFB1-treated chickens. Our results suggest that NAC provided protection against negative effects on performance, liver and renal damage, and biochemical alterations induced by AFB1 in broiler chickens. Effects of NAC alone on chick performance were also evaluated. Addition of NAC to diet (800 mg/kg BW) did not negatively affect feed consumption, conversion index, or serum chemistry and did not induce structural changes in the liver or kidney.

Acetylcysteine↗
PubMed1999

Laser in situ keratomileus using the LaserSight 200 laser: results of 950 consecutive cases.

PURPOSE: To examine the refractive outcome in 950 consecutive eyes having laser in situ keratomileusis (LASIK) by 1 surgeon with experience in keratomileusis. SETTING: Outpatient excimer laser surgical facility. METHODS: This study comprised 950 consecutive eyes of 475 patients having LASIK as a primary procedure with a LaserSight 200 excimer laser (8.51 software). A nasal hinged flap and a Chiron microkeratome were used. Preoperative cycloplegic refraction was done only in patients younger than 25 years and in all hyperopic cases. Subjective preoperative and postoperative manifest refractions were done after autorefractometry in all cases. In cases of hyperopia, the software was modified by adding 30% to the refractive error. Enhancement results are not included. RESULTS: Of the 950 eyes, 893 (94.00%) were myopic and 57 (6.00%), hyperopic. In the low myopia group (1.00 to 3.99 D) of 223 eyes (24.97%), mean spherical equivalents (SEs) were -2.90 D +/- 0.56 (SD) preoperatively, -0.46 +/- 0.6 D 3 months postoperatively, and -0.41 +/- 0.5 D 6 months postoperatively. In the moderate myopia group (4.00 to 5.99 D) of 205 eyes (22.96%), respective mean SEs were -4.90 +/- 0.7 D, -0.90 D +/- 0.9 D, and -0.67 +/- 0.7 D. In the high myopia group (6.00 to 9.99) of 266 eyes (25.30%), the respective means were -7.70 +/- 1.3 D, -0.76 +/- 0.99 D, and -0.60 +/- 0.8 D. In the extreme myopia group (10.21 to 30.00) of 199 eyes (22.28%), the respective means were -13.30 +/- 2.9 D, -1.30 +/- 1.4 D, and -1.13 +/- 1.3 D. For the entire myopic group, the mean astigmatism was +1.55 +/- 1.38 D, +1.09 +/- 0.92 D, and +0.87 +/- 0.77 D, respectively. The low hyperopia group (1.00 to 2.99 D) of 39 eyes (68.42%) had a mean preoperative SE of +1.80 +/- 0.59 D and mean postoperative SEs of +1.00 +/- 0.76 D at 3 months and +1.16 +/- 0.52 D at 6 months. The respective means in the moderate hyperopia group (3.00 to 6.00) of 18 eyes (31.57%) were +4.62 +/- 1.19 D, +3.71 +/- 1.12 D, and +4.00 +/- 1.07 D. CONCLUSIONS: Laser in situ keratomileus for myopia using the LaserSight 200 excimer laser was stable with time and safe for the correction of different degrees of myopia. In the hyperopic group, marked regression occurred in a large percentage of patients. Thus, we will not perform LASIK for hyperopia until the software improves.

Adult↗
PubMed1996

Endoscopic injection of ethanolamine as a treatment for achalasia: a first report.

BACKGROUND AND STUDY AIMS: The present study aimed to test the hypothesis that endoscopic sclerotherapy may effectively reduce the occurrence of spasm at the level of the gastric cardia, offering an effective treatment for achalasia. PATIENTS AND METHODS: We prospectively treated 33 achalasia patients by repeated injection of ethanolamine oleate at the cardiac level. Twenty patients (series I) were reassessed after six to nine months, with a mean follow-up of 31.5 months (range 13-54 months) after treatment. In an attempt to avoid stricture formation, the last 13 patients (series II) were then treated on the basis of the need to reduce the number of injections per session and avoid new treatment while inflammatory or ulcerative signs, or both, were present. The series II patients were followed up for a mean of 11 months (range 1.7-21.3 months). RESULTS: Overall, a mean of 3.6 treatments was required, and the result was described as "excellent" or "good" in 31 of the 33 patients after one month. Two patients had a poor response to the treatment, but their condition improved after repeat treatment. After six to nine months, the subjective parameters (dysphagia, regurgitation, bronchopulmonary symptoms) and objective parameters (diameter of the esophagus, scintigraphy, manometry), had improved considerably after the treatment in the series I patients, and this improvement was sustained for more than two years, at least by subjective criteria. Four of the 20 series I patients developed mild or moderate fibrotic strictures, but these were managed successfully by standard 15-20 mm balloon dilation. No additional strictures were recorded in the last thirteen patients treated (series II). None of the patients who were followed up had to undergo surgery due to failure of the treatment. CONCLUSION: Endoscopic sclerotherapy appears to be a very promising alternative to the currently available therapeutic tools for achalasia.

Adult↗
PubMed1995

[Evaluation of the cervical factor in ovulation induction].

Post coital sperm penetration tests performed in 66 women under study for infertility, the purpose was to evaluate the ovulation induction effect over mucus quality and over sperm penetration. They were divided in three groups: 1) 28 women with evidence of spontaneous ovulation (control group), 2) 26 patients in which ovulation was induced with comiphene citrate and 3) 12 patients in which ovulation was induced with menotropins. The results showed that CC had an adverse effect over cervical mucus (p < 0.001), while in patients treated with menotropins the cervical mucus quality was not modified. Sperm penetration in patients under CC had a tendency to lower values than those in women of the control group, but these were statistically lower than those in patients under menotropins (p < 0.05). These results show the adverse effect of CC and the benefit of menotropins over cervical mucus and sperm penetration.

Adult↗
PubMed1994

A specifically apical sub-membrane intermediate filament cytoskeleton in non-brush-border epithelial cells.

Although many pieces of evidence support the notion of a role for the cytoskeleton in epithelial polarization, no cytoskeletal component has been found to be specifically apical, except for some actin-binding proteins. Here we report the apical distribution of a 53 kDa cytokeratin. Furthermore, this cytokeratin co-purified with biotinylated apical plasma membrane proteins in high density complexes. Differential biotinylation of the basolateral domain showed that the 53 kDa protein is mainly attached to the apical membrane, although a companion 58 kDa protein attaches to both apical and basolateral membrane proteins. Immunoprecipitation experiments indicated that a number of apical components are directly or indirectly linked to the 53 kDa protein. These results indicate the existence of a terminal web-like structure in non-brush-border cells, which attaches to the apical domain and may play a role in apical polarization, especially during the acquisition of polarity from non-polarized cellular stages.

Animals↗
PubMed1993

[The physician-patient relation through a Balint group].

OBJECTIVE: To evaluate by means of a contents analysis a Balint Group (BG) after 7 years in operation, to find which type of patients are most disturbing for the General Practitioner and to analyse the sort of feelings they provoke. DESIGN: A retrospective descriptive study which uses qualitative analysis methodology. SETTING: The BG under analysis was created in the heart of the Catalan Society of Family and Community Medicine in 1984. PATIENTS: 21 sessions were analysed, covering 18 patients. INTERVENTIONS: The variables studied were: the motives for presentation, the sort of patient presenting and the doctor's feeling towards them. MEASUREMENTS AND MAIN RESULTS: Two types of patients stood out: those with somatization disorders and those with a very poor prognosis. The first (12 out of 18) unsettled the professional and caused him/her to lose grip on his/her role. The GP often trivialised their requests or thought they were pretending. Those sessions analysed where patients had a poor prognosis made clear the high degree of empathy shown by the doctor. Questions were raised as to how to tackle the illness both with the patient and his/her family. Feelings of distress, fear, anguish-exhaustion-impotence and rejection-aggression of the doctor towards particular patients were analysed. CONCLUSIONS: The questioning of the doctor's social role or professional identity by particular patients makes it difficult for him/her to maintain a long-term therapeutic relationship with them. The BG was useful for the participants, because of the group dynamic and also because they found out the possibilities and limitations of their treatment.

Adult↗