Copper in foods, beverages and waters from South East Spain: influencing factors and daily dietary intake by the Andalusian population.

The copper content of 225 food, 49 beverage and twelve potable water samples were determined using atomic absorption spectrometry (AAS). Analyses of NIST and BCR reference materials demonstrated the accuracy of this technique. The highest copper levels were found in dried fruit and legumes, followed by organ meats, molluscs and crustaceans, cephalopods, cereals and sausages, respectively. In cereals, legumes and fruit, copper levels increased significantly with increasing levels of protein and decreasing carbohydrate content (p < 0.001). In meat and meat by-products, copper concentrations found in organ meats were significantly higher (p < 0.01). In fresh fish products, copper levels in shellfish were significantly higher than those measured in fish (p < 0.001). In vegetables, the copper concentrations found in mushrooms were significantly higher (p < 0.005). Mean copper concentrations analysed in cheese were statistically higher than those determined in other dairy products (p < 0.01). In beverages, copper levels determined in rum and juices were significantly higher (p < 0.001). Beverages for which a vegetable component was directly used in their manufacturing process (juices, wines and beers) had statistically higher copper levels when compared with fresh drinks. The daily dietary intake (DDI) of copper in the Andalusian diet was 1979 mug day(-1) per person. Cereals, meat, meat by-products and vegetables are the food categories that are the main source of copper in the daily diet. Taking into account the dietary reference intakes and upper levels (900 and 10, 000 mug Cu day(-1) for healthy adults, respectively), the mean copper DDI found indicate that for most of healthy adult individuals from the area, no adverse effects occur in relation to copper nutrition (deficiency or toxicity). Potable waters supplied 53 mug day(-1), which constitutes on average 0.025% of the maximum tolerable daily intake of this element set by the Joint FAO/WHO Expert Committee.

[Evolution of nutritional biochemical parameters in hemodialysis patients during a one-year follow-up period]. / Evolución de parámetros bioquímicos nutricionales en pacientes de hemodiálisis durante un año de seguimiento.

Current high survival in hemodialysis patients (52% at 5 years) have made the chronic manifestations to emerge such as the high hyponutrition prevalence of these patients, as well as the importance of the nutritional status in their morbimortality. The reason for protein-caloric hyponutrition is multifactorial, although chronic inflammatory conditions associated to the dialysis technique are becoming more and more relevant. The variations in several nutritional biochemical parameters (total proteins, plasma albumin, transferrin, and total cholesterol) have been assessed in 73 hemodialysis patients for one year. The mean age of the patients was 53.3 +/- 18.69 years (43 males and 30 females). The average on hemodialysis program was 43 +/- 33 months, with a mean session duration of 246 +/- 24 minutes, and mean hemodialysis dose administered of 1.37 +/- 0.27 (KT/V) (second generation Daurgidas). A decrease in all the biochemical parameters assessed has been observed, with statistically significant differences: total proteins (p < 0.001), albumin (p < 0.00001), total cholesterol (p < 0.05), and transferrin (p < 0.01). The evolution of the nutritional biochemical parameters assessed showed an important nutritional deterioration of the patients remaining stable with the therapy.

Different radical scavenging tests in virgin olive oil and their relation to the total phenol content.

Four different antioxidant tests (ABTS*+, DPPH, ORAC, beta-carotene-linoleate model system) were used to determine the free-radical scavenging activity of 39 extra virgin olive oils (EVOO) and compare the total phenol content by the Folin-Ciocalteu method. The correlation between the total phenols and antioxidant capacities measured by the four methods was very high, and highest with ABTS*+ (R2 = 0.9905). Some of these methods of measurement were applied to olive-oil samples (OO), with approximately a 50% decrease in the value of the antioxidant capacity in comparison with values found for EVOO. In conclusion, the results show that all the methods tested were suitable for determining the antioxidant capacity of olive oil. The Picual variety of extra-virgin olive oil showed high antioxidant activity.

Longitudinal study of serum zinc and copper levels in hemodialysis patients and their relation to biochemical markers.

A 6-mo longitudinal study of 48 hemodialysis patients (HPs) with chronic renal failure was performed. Three blood samplings were done. Samples of whole blood from each patient were collected during hemodialysis sessions after passing through the artificial kidney. Zinc and copper levels were measured by atomic absorption spectrometry. Additionally, 36 biochemical indexes were evaluated during the study. Fifty-two healthy matched controls were also considered. Mean serum zinc and copper concentrations in HPs were significantly decreased (Zn) and increased (Cu), when compared with healthy controls (p < 0.01). Zinc concentrations found in the first and second blood samplings from patients were significantly lower than those measured for the third sampling (p < 0.01). The etiology of chronic renal failure influenced the statistically serum Zn levels of patients (p < 0.05). Serum copper levels of HPs were significantly diminished by the existence of secondary associated diseases (p < 0.01). Uric acid and parathyroid hormone, and total-cholesterol and glutamic-pyruvic-transaminase levels were significantly (p < 0.05) and linearly related with serum zinc and copper concentrations, respectively. From all of indexes, creatinine, direct bilirubin, magnesium, calcium, parathyroid hormone, transferrin, and albumin were statistically modified along the longitudinal study (p < 0.05). Transferrin serum levels were significantly diminished in the third blood sampling, indicating the tendency toward anemia in the patients. This result is reinforced by low levels of biochemical and hematological indexes related with iron body staus.

[Nutritional assessment in a Moroccan university population during Ramadan]. / Evaluación nutricional de una población universitaria Marroquí en el tiempo de Ramadán.

The aim of this work was to assess nutritional status in Muslim population, bigger and bigger in our universities, in a period during which its dietary habits change considerably. The study has been performed in a population of Muslim students from the University of Granada, and has been compared to a non-Muslim population within the same setting. Study subjects undertook a questionnaire in which they reported the diet consumed each day during the Ramadan period. Macronutrient analysis for such diet was performed with Dietsource software. On the other hand, anthropometrical parameters were taken before and after the study period to observe their change and obtain conclusions on nutritional status. It has been observed that lipid intake of Muslims during the Ramadan period was excessive (48% of total energy), by decreasing hydrocarbons and particularly proteins. This is highlighted by means of the anthropometrical study, observing a decrease in measurements such as muscular area of the arm, the arm area, the muscle perimeter of the arm, and weight, with an increase in arm fat, perimeter of the arm, leg and mid-ieg circumference in the Muslim group, which are in contrast with parameters in the non-Muslim group. From our results, we may stress that during the Ramadan period macronutrient intake values are not appropriate as compared to standard recommendations in Spain. Besides, it is striking to observe how anthropometrical measurements related to fat increase whereas those related to muscular mass decrease.

[Longitudinal study on the body mass index (BMI) of dialysis patients]. / Estudio longitudinal del Indice de masa corporal (IMC) en pacientes en diálisis.

Chronic renal failure is commonly related to hyponutrition, affecting approximately on third of patients with advanced renal failure. We carried out a longitudinal study to assess nutritional evolution of 73 patients on a regular hemodialysis program, assessing changes in the anthropometrical parameter body mass index (BMI) and its correspondence to biochemical nutritional parameters such as total protein (TP) levels and serum albumin (Alb). Every three months plasma TP and albumin levels were collected and BMI was calculated by the standard formula: post-dialysis weight in kg/height in m2. For classifying by BMI categories, overweight and low weight were defined according to the WHO Expert Committee. Studied patients had a mean age of 53 years, 43 were male and 30 were female patients. BMI in women was lower than that in men (p < 0.001), as well as TP (p < 0.001) and Alb (p < 0.001) levels. Mean BMI was 29.3 kg/m2. Three point two percent of the determinations showed low weight, 12.16% overweight, and 83.97% normal BMI. TP were normal in 90.76% and decreased in 9.24%. Alb was normal in 82.2% and low in 17.78%. After the follow-up time (21.6 months, minimum 18 months, maximum 53 months), the Kruskal-Wallis test did not show a statistically significant change for BMI but it did show a change for the biochemical parameters albumin and total proteins (p < 0.05): nutritional impairment in CRF patients is manifested on biochemical parameters (TP and Alb) with no reflection on anthropometrical data.

[Nutritional assessment of a university population]. / Evaluación nutricional de una población universitaria.

In this work, we have planned to perform a nutritional assessment of a group of 50 students from the University of Granada, to which questionnaires have been administered relating to 24-hour remembrance of type and frequency of food consumption, for 30 days. In order to know macro- and micronutrients intake, the results have been analyzed with DietSource software. At the same time, anthropometrical measurements have been taken to verify their possible change during the study period. We have been able to observe a protein intake slightly higher than the recommended intake, similarly to what occurs with lipids. The studied group positively values menus with high content in meat, whereas deficiencies in fruit and vegetable intake are observed. In addition, there is a variation of anthropometrical measurements of these individuals during the study period. We also noticed a deficiency in some micronutrients such as iron, zinc, calcium, iodine, cupper, selenium, vitamin E, and folic acid in all the studied population. However, vitamin C and thiamine levels in both groups and riboflavin levels in women may be considered adequate. From these results, we may highlight a nutrition unbalance in this population group since we have observed some deficiencies in the intake of important micronutrients for health maintenance and promotion, and macronutrient consumption that diverges from the established recommendations.

Calculation of the solution properties of flexible macromolecules: methods and applications.

While the prediction of hydrodynamic properties of rigid particles is nowadays feasible using simple and efficient computer programs, the calculation of such properties and, in general, the dynamic behavior of flexible macromolecules has not reached a similar situation. Although the theories are available, usually the computational work is done using solutions specific for each problem. We intend to develop computer programs that would greatly facilitate the task of predicting solution behavior of flexible macromolecules. In this paper, we first present an overview of the two approaches that are most practical: the Monte Carlo rigid-body treatment, and the Brownian dynamics simulation technique. The Monte Carlo procedure is based on the calculation of properties for instantaneous conformations of the macromolecule that are regarded as if they were instantaneously rigid. We describe how a Monte Carlo program can be interfaced to the programs in the HYDRO suite for rigid particles, and provide an example of such calculation, for a hypothetical particle: a protein with two domains connected by a flexible linker. We also describe briefly the essentials of Brownian dynamics, and propose a general mechanical model that includes several kinds of intramolecular interactions, such as bending, internal rotation, excluded volume effects, etc. We provide an example of the application of this methodology to the dynamics of a semiflexible, wormlike DNA.

Selenium concentrations in serum of individuals with liver diseases (cirrhosis or hepatitis): relationship with some nutritional and biochemical markers.

Serum concentrations were measured in individuals (n = 50) with liver diseases (cirrhosis and hepatitis) by hydride generation atomic absorption spectrometry in a cross-sectional study. Mean serum selenium levels determined in patients with cirrhosis (n = 12) or with hepatitis (n = 38) were significantly lower (P<0.01) than those measured in control groups mainly due to a decreased liver function. Mean serum selenium concentrations were significantly lower in cirrhotic individuals when compared with patients with hepatitis (P<0.05). Therefore, the severity of the live injury is a factor conditioning the impairment in the selenium body status observed in individuals with hepatopathies. In hepatic patients serum total cholesterol levels showed a significant correlation with serum selenium concentrations (r=0.912, P<0.05) demonstrating the important role of selenium as an antioxidant agent; similarly, gamma-glutamic-transferase levels were significantly correlated with the serum selenium levels (r=-0.803, P<0.05) indicating that when the intensity of the hepatic injury increases (enhancement in serum GGT levels) concomitantly the serum selenium levels decrease significantly. No significant relationships between serum selenium levels and sex or age of patients were observed.

Determination of zinc levels in waters from southeastern Spain by electrothermal atomic absorption spectrometry: relationship with industrial activity.

An efficient method for the determination of nanogram levels of zinc in waters (potable, irrigation, waste and sea waters) is described. Acidified water samples were analyzed by an accurately optimized time/temperature program for electrothermal atomic absorption spectrometry. The samples were previously treated with a matrix modifier consisting of 0.1% Mg(NO3)2 in 0.5 M HNO3 and injected through a graphite tube with L'Vov platform. Sample recoveries, repeteability, and analyses of NIST reference material demonstrated the reliability and accuracy of this technique. Zinc concentrations ranged from 2.0 to 73.0 microg l(-1). No significant differences among the mean zinc levels determined in the four types of water considered from southeastern Spain were found. Zinc concentrations in waters from the zone were not affected by human and industrial activity.

Calculation of hydrodynamic properties of small nucleic acids from their atomic structure.

Hydrodynamic properties (translational diffusion, sedimentation coefficients and correlation times) of short B-DNA oligonucleotides are calculated from the atomic-level structure using a bead modeling procedure in which each non-hydrogen atom is represented by a bead. Using available experimental data of hydrodynamic properties for several oligonucleotides, the best fit for the hydrodynamic radius of the atoms is found to be approximately 2.8 A. Using this value, the predictions for the properties corresponding to translational motion and end-over-end rotation are accurate to within a few percent error. Analysis of NMR correlation times requires accounting for the internal flexibility of the double helix, and allows an estimation of approximately 0.85 for the Lipari-Szabo generalized order parameter. Also, the degree of hydration can be determined from hydrodynamics, with a result of approximately 0.3 g (water)/g (DNA). These numerical results are quite similar to those found for globular proteins. If the hydrodynamic model for the short DNA is simply a cylindrical rod, the predictions for overall translation and rotation are slightly worse, but the NMR correlation times and the degree of hydration, which depend more on the cross-sectional structure, are more severely affected.

Application of artificial aging techniques to samples of rum and comparison with traditionally aged rums by analysis with artificial neural nets.

Artificial aging techniques were applied to samples of rum. These samples were then compared, by artificial neural nets, with traditionally aged rums. Analysis was based on the phenolic and furanic composition of each sample. There were found to be few statistical differences between samples, thus confirming the possibility of applying artificial aging techniques to obtain rum with phenolic and furanic characteristics that are similar to those of rum obtained by traditional methods.

Essentiality of selenium in the human body: relationship with different diseases.

In the present review different aspects related to the essential element selenium in the human organism are considered. A large number of human studies have been performed in order to improve knowledge on the influence of this element in the origin and development of several degenerative diseases. Selenium deficiencies among human beings as well as animals are being recognized worldwide to be related to a number of pathologies. This element has also the special characteristic that the range between its essential and toxic character is very close, and consequently daily dietary intake should be appropriately monitored in individuals. Nevertheless, nowadays there is still a lot of controversy about the optimum dietary level of this element in order to cure or to prevent the appearance of diseases such as cirrhosis, cancer, diabetes, or cardiovascular pathologies. Results obtained in several animal and epidemiological studies have indicated that Se could constitute a dietary factor with protective action against several degenerative diseases.

Comercialización de los nuevos alimentos obtenidos por biotecnología / Commercialization of new biotechnological food products

La biotecnología es una ciencia que actualmente está realizando grandes impactos en el campo de la alimentación. La aparición de nuevos alimentos resulta ser un campo de gran interés bromatológico. Estos alimentos para poder salir al mercado, con una "seguridad adecuada" tienen que ser previamente evaluados: una vez realizada dicha evaluación, pasarán a ser autorizados y finalmente comercializados (AU)

[Nutritional state of iron in the institutionalized aged: study of intake and hematological indices]. / Estado nutricional en hierro en ancianos institucionalizados: estudio de la ingesta e índices hematológicos.

In this study we determined the nutritional state of iron in 93 elderly people who were institutionalized in Granada, by means of a determination of their ingested iron, as well as the determination of the serum iron, hematologic parameters (hemoglobin and hematocrit), and the corpuscular indexes (mean corpuscular volume and mean corpuscular hemoglobin). The elderly people had an iron intake that was considered to be adequate (10.2 +/- 2.1 mg/day), and this is not related to the hematological parameters studied. 4% of the men, and 22% of the women showed hemoglobin values that were considered to be low.

Urine arsenic concentrations in healthy adults as indicators of environmental contamination: relation with some pathologies.

Arsenic concentrations were determined in 126 urine samples by hydride generation atomic absorption spectrometry. Samples were mineralized with nitric acid in a thermostated mineralization block. This technique was compared with a method that involves mineralization in a microwave digestion bomb. A mean recovery percentage of 100.80 +/- 5.57% was obtained. The relative standard deviation ranged from 1.7 to 10.52%. It was found that subject sex and age did not affect urine As levels (P > 0.05). The mean urine As levels in patients with hepatic injury (4.24 +/- 1.98 micrograms/l), diabetes (3.44 +/- 2.36 micrograms/l) and myocardial infarction (3.64 +/- 1.85 micrograms/l) were not statistically different (P > 0.05) to that found in the control group (healthy subjects) (3.68 +/- 2.27 micrograms/l). This result could be related to the fact that the regulation of As in the human organism is independent of these diseases. Measured As concentrations in the eight basic health zones of the study area were not statistically different (P > 0.01). This fact demonstrates the existence of a similarly low environmental As distribution in coastal and mountainous zones.

Serum zinc and copper concentrations and Cu/Zn ratios in patients with hepatopathies or diabetes.

The serum zinc and copper levels, as well as Zn/Cu ratios, were determined in 30 patients (18 with diabetes and 12 with hepatopathies) and compared to healthy-age matched controls by atomic absorption spectrometry. Serum Zn (0.946 +/- 0.302 mg/l) and Cu (0.952 +/- 0.355 mg/l) concentrations were not significantly different in patients with hepatopathies as compared to controls (p > 0.05). Serum Zn concentrations (0.778 +/- 0.164 mg/l) were significantly lower in diabetic patients than those determined in controls (p < 0.01). In contrast, Cu levels (0.987 +/- 0.305 mg/l) were not significantly different (p > 0.05) than in controls. Serum Cu/Zn ratios were not significantly different in patients with diabetes or hepatopathies than those measured in healthy controls (p > 0.05). In patients, no statistically significant differences were observed in the Zn, Cu and Cu/Zn with respect to sex (p > 0.05) or age (p > 0.05).

Serum zinc levels in healthy subjects from southeastern Spain.

The serum zinc (Zn) concentrations of 80 healthy subjects (48 male, 32 female) from southeastern Spain were determined by atomic absorption spectrometry. The samples were digested by heating in a 4:1 mixture of nitric and perchloric acids. The concentration of Zn was determined against a Contox Trace Metal Serum Control Panel A standard reference. Zn concentrations in the standard were found to be 2.332+/-0.489 mg/L, with a mean recovery of 102.7%. In the serum samples, the relative standard deviation was <6% for the range of concentrations determined: 0.420-1.540 mg/L for women (mean value 0.947+/-0.265 mg/L) and 0.490-1.480 mg/L for men (mean value 0.951+/-0.243 mg/L). In healthy subjects, no statistically significant differences were observed in the Zn levels with respect to their sex (p > 0.05) or the location where they lived (mountainous vs coastal zones). It is concluded that the dietary Zn intake and Zn status for healthy adults in this region of Spain are within normal values.

Zinc and copper concentrations in serum from Spanish women during pregnancy.

A cross-sectional study of serum zinc (Zn) and copper (Cu) levels in 31 healthy pregnant women and 51 healthy, nonpregnant controls living in the Mediterranean area of Granada, Spain, was performed. The subjects were divided into two groups: Group A, consisted of pregnant women in three categories according to the trimester of pregnancy, and Group B consisted of nonpregnant women acting as controls. In pregnant women, serum Zn levels were found from 0.300-1.340 mg/L and serum Cu from 0.936-2.304 mg/L, whereas in the nonpregnant women group, the mean serum levels were 0.947+/-0.265 mg/L for Zn and 1.092+/-0.365 mg/L for Cu. Serum Zn progressively decreased with gestation. Mean Zn levels were 0.829+/-0.253, 0.846+/-0.329, and 0.620+/-0.142 mg/L, corresponding to the first, second, and third trimesters of pregnancy, respectively. Serum Zn concentrations were significantly lower in pregnant women as compared to controls: 0.712+/-0.236 mg/L vs 0.947+/-0.265 mg/L, respectively (p < 0.05). In contrast, Cu levels increased with period of gestation from 1.053+/-0.498 mg/L in the first trimester to 1.616+/-0.304 mg/L in the second and 1.689+/-0.344 mg/L in the third. Serum Cu levels in the second and third trimesters of pregnancy were significantly higher (p < 0.05) than those determined during the first trimester and for nonpregnant controls. Both Zn and Cu during pregnancy did not appear to be dependent on the subject's age (p > 0.05).

Simulation of the conformation and dynamics of a double-helical model for DNA.

We propose a partially flexible, double-helical model for describing the conformational and dynamic properties of DNA. In this model, each nucleotide is represented by one element (bead), and the known geometrical features of the double helix are incorporated in the equilibrium conformation. Each bead is connected to a few neighbor beads in both strands by means of stiff springs that maintain the connectivity but still allow for some extent of flexibility and internal motion. We have used Brownian dynamics simulation to sample the conformational space and monitor the overall and internal dynamics of short DNA pieces, with up to 20 basepairs. From Brownian trajectories, we calculate the dimensions of the helix and estimate its persistence length. We obtain translational diffusion coefficient and various rotational relaxation times, including both overall rotation and internal motion. Although we have not carried out a detailed parameterization of the model, the calculated properties agree rather well with experimental data available for those oligomers.