Biomedical subjects

C Díaz Romero

Publications and source records attributed to C Díaz Romero.

16 recordsLinked to original sources

PubMed2005

Sodium, K, Ca, Mg, Fe, Cu, and Zn concentrations in molluscs from the Magellan Strait (Chile): their contribution to dietary intake.

The concentrations of the essential metals Na, K, Ca, Mg, Fe, Cu, and Zn were determined in 126 specimens of molluscs belonging to five different species: Mytilus chilensis, n=47; Nacella deaurata, n=65; Aulacomya ater, n=4; Fissurella picta, n=4; Acanthina monodon, n=6, collected from the coastline of the Magellan Strait. Significant differences were obtained among the mean metal concentrations in the mollusc species considered. The contribution to the dietary daily intake of these metals for the consumption of one serving of these molluscs was high, especially the contribution to the Fe intake for the consumption of N. deaurata. Some significant differences were observed among the mean concentrations for the studied metals according to the zone of sampling. The influence of the zone of sampling on the mean concentration of metals in N. deaurata was higher than in M. chilensis. The application of lineal discriminant analysis (LDA) made it possible to differentiate statistically between specimens according to the mollusc species. Within the each mollusc species, the LDA helped to identify specimens according to the zone of sampling and weight/length ratio.

Animals↗

PubMed2004

Application of linear discriminant analysis to the biochemical and haematological differentiation of opiate addicts from healthy subjects: a case-control study.

OBJECTIVE: Biochemical and haematological parameters of nutritional interest were determined in the serum of opiate addicts in order to compare them with those obtained in healthy subjects. Linear discriminant analysis was applied for the differentiation of the opiate addicts. SUBJECTS: Sera of 106 opiate addicts in detoxification treatment (n=19) or in Methadone Maintenance Treatment Program (MMTP) (n=87) were studied. DESIGN: : The determination of classical biochemical and haematological parameters in blood samples was carried out using standardized methods. Determination of retinol and alpha-tocopherol was carried out by high-performance liquid chromatography with diode-array detector. Folic acid and vitamin B(12) were determined using competitive binding techniques. Minerals were determined by flame emission spectrometry (Na and K) and atomic absorption spectrometry with air-acetylene flame (Ca, Mg, Fe, Cu and Zn) or with hydride generation (Se). Phosphorous was determined using a colorimetric method with ammonium molibdate. All statistical analyses were performed by means of the SPSS version 10.0 software for Windows. RESULTS: Stepwise linear discriminant analysis simplified the system to the following variables: Na, K, Mg, number of leucocytes, triglycerides, GPT, glucose, albumin, retinol and folic acid; and 90.1% (86.4% after crossvalidation) of correct classification was obtained. Representing the first and second discriminant functions, the control groups were well separated from opiate addicts. CONCLUSIONS: Applying linear discriminant analysis on several biochemical and haematological parameters, the opiate addicts could clearly be differentiated from the control individuals, and a tendency to differentiate the opiate addicts in MMTP and in detoxification treatment was observed.

Adult↗

PubMed2004

Manganese, nickel, selenium and cadmium in molluscs from the Magellan Strait, Chile.

The concentrations of manganese, selenium, nickel and cadmium were determined in 112 samples of molluscs belonging to mussels (Mytilus chilensis, n = 47) and limpets (Nacella deaurata, n = 65), which were collected from the coastline of the Magellan Strait, Chile. Four (6.2%) samples of limpets exceeded the maximum limits for cadmium established in Europe. Limpets showed higher mean manganese, nickel and cadmium concentrations than mussels, whilst the mean selenium concentration in mussels was higher. The consumption of one serving (100 g) of molluscs represents a considerable contribution to the dietary daily intake of selenium, and limpets make a significant contribution to the manganese and cadmium intakes. The sampling zone influenced the trace element concentrations, and different uptakes were observed between the mollusc species.

Adult↗

PubMed2002

Fast determination of retinol and alpha-tocopherol in plasma by LC.

A fast, selective and economical method for the determination of retinol and alpha-tocopherol is presented. Both vitamins are separated by high-performance liquid chromatography (HPLC) in less than 4 min using an isocratic elution with methanol. The robustness of the method was checked in real samples, obtaining relative standard deviation lower than 3%. The described method was satisfactorily applied to serum samples proceeding of patients enrolled in a METHADONE maintenance treatment program. The retinol concentrations in the serum of these patients fell into the normal interval of concentrations; however, the serum alpha-tocopherol contents were higher than the normal values.

Chromatography, High Pressure Liquid↗

PubMed2002

[Concentrations of calcium, magnesium, sodium and potassium in human milk and infant formulas].

Concentrations of calcium, magnesium, sodium and potassium were determined in 55 samples of mature human milk from Canary women and 5 samples of powdered infant formula. According to the literature our data fell within the normal intervals described for each kind of milk. The mean concentration of Ca, Mg, Na y K of powdered infant formula was higher than those concentrations found in the human milks. Significant differences among the concentrations of Ca, Mg and Na for the milks of the considered mothers were observed. Only the Ca intakes for infants fed with human milk were lower than those requirements recommended by the Food and Nutrition Board (1989). However, the infants fed with powdered infant formula had an adequate intake of all the studied metals. A progressive decrease of the Na, K and Ca concentrations with the lactation stage was observed. Maternal age, parity and sex of the newborns did not affect the metal concentrations significantly.

Adult↗

PubMed2000

Selenium and cancer: some nutritional aspects.

The level of selenium in cancer patients is lower than that in control subjects. However, low selenium levels in body fluids can be due to the malnutrition observed in these patients. There is evidence from epidemiologic studies that high dietary selenium intakes and high selenium status in people are associated with lower cancer mortality. However, contradictory information has been found in some prospective studies. The presence of other nutrients in selenium-rich foods can influence the role of the selenium in cancer etiology. Therefore, there are selenium antagonistic elements that inhibit the anticarcinogenic effects of selenium and other antioxidant micronutrients such as ascorbic acid, retinol, beta-carotene, alpha-tocopherol, and some other elements have a synergistic effect on the prevention of cancer.

Animals↗

PubMed2000

Concentrations of iron, copper and zinc in human milk and powdered infant formula.

Concentrations of iron, copper and zinc were determined in 56 samples of mature human milk from Canarian women and 5 samples of powdered infant formula. According to the literature our data fall within the normal limits in each kind of milk. The mean concentration of Fe, Cu and Zn of powdered infant formula was significantly higher than those concentrations found in the human milks. Significant differences among the concentrations of the studied metals for the milks of considered mothers were observed. The Fe, Cu and Zn intakes of infants fed with human milk are lower than the requirements recommended by the Food and Nutrition Board (1989). However, the infants fed with powdered infant formula had consumed an adequate intake of Fe and Cu. A progressive decrease of the metal concentrations with the lactation stage was observed. The human milk obtained in spring presented Fe and Zn concentrations lower than in autumn, which could be due to changes in nutritional habits of the mothers. Age of mother and number of previous children seem to influence the Zn and Cu concentrations of human milk.

Adult↗

PubMed2000

[Biochemical assessment of nutritional status in the Canary Islands population (1998)].

UNLABELLED: Nutrition surveys include information about dietary intake and nutritional status utilising clinical, biochemical and anthropometric measurements. OBJECTIVE: To evaluate the nutritional status of the Canary Island population by means of biochemical and haematological indicators METHODOLOGY: A cross-sectional study was realised in a representative subsample aged 6 to 75 years that participated in the Nutritional Survey of the Canary Islands, 1997-98 (ENCA). We determined levels of ferritin and vitamin B12 (enzyme-immunoassay), serum and erythrocytic folic acid (automated ionic catchment), retinol, tocopherol and carotenes (high performance liquid chromatography) and minerals (atomic absorption spectrometry) RESULTS: There were neither sex, age nor socio-economic differences in the reference population sample and the ENCA sample. The participation rate was 48.8%. 25% of the women had deficit levels of ferritin and the prevalence of anaemia in women over 18 years was 2.9%. 13% of the population had low erythrocyte folic acid levels, that increased with age, and 3.4% had low vitamin B12 levels, which, on the contrary, decreased with age, 15% of the population presented a deficit of alpha-tocopherol and 5.2% of retinol, being more frequent in the youngest group, and 56.4% and 41.1% exhibited low levels of beta-carotene and lycopene respectively. Among mineral and trace elements, low levels of manganese drew attention due to its heightened prevalence, and, to a lesser extent, selenium. CONCLUSIONS: In spite of the complexity of its interpretation, this data yields a precise estimation of nutritional status for certain vitamins and minerals in the Canary Island population.

Adolescent↗

PubMed1999

Chemometric studies of several minerals in milks.

A statistical study of correlation, factorial, and discriminant analysis on the metal composition (Se, Fe, Cu, Zn, Na, K, Ca, Mg) of different types of milks (human, cow, goat, pasteurized, and powdered infant formula) was carried out to establish the relationships between the metal concentrations and, therefore, differentiate the samples according to the type of milk. A large number of significant intermetallic correlations were found in all samples, which could be due to biological relationships between the metals studied. After the factorial analysis, the dimension space was reduced from eight variables to two factors, accounting for approximately 71.4% of the total variance. After an orthogonal rotation, the first factor was positively correlated with Ca and the second factor with Fe. The representation of the scores makes it possible to separate not only human milk from powdered infant formula but also to separate both of these from the other milks. In the discriminant analysis, four discriminant functions were obtained, which are linear combinations of the quantitative variables that best explain the differences among the different milks analyzed. These functions make it possible to classify 98% of the samples analyzed within each type of milk correctly. Therefore, discriminant functions obtained here can be used to identify the origin of any milk sample.

Animals↗

PubMed1995

Urinary selenium status of healthy people.

Urinary selenium (Se) concentrations (microgram/l of urine and microgram/g of creatinine) and urinary Se excretions (microgram/d and microgram/d.kg of body weight) have been determined in healthy Canarian people. Urinary Se status was relatively low and similar to those data published from European regions. Females excreted daily significantly (P = 0.005) higher amounts of Se per kg of body weight in urine than males. An increase of daily urinary Se excretion was observed up to 30 years of age. Children (< 10 years old) had daily urinary Se excretion per kg of body weight higher than persons with age > 10 years old. Both units of Se excretion, microgram/d and microgram/d.kg, increased or decreased respectively with weight and height of the individuals. Food habits such as consumption of rich protein or rich fibre food, and drinking alcohol or coffee as well as smoking do not seem to influence the urinary Se status. Depletion of daily urinary Se excretion was observed with the increase of physical exercise. Unit of concentration (microgram/g of creatinine) is a more adequate indicator of the urinary Se excretion than the unit microgram/l.

Age Factors↗

PubMed1994

Urinary selenium concentrations in heroin abusers.

Urinary selenium (Se) concentrations (micrograms Se/l and microgram Se/g creatinine) have been determined in heroin abusers and in healthy controls. Heroin abusers showed significantly (P < 0.050) lower urinary Se concentrations (microgram Se/l and microgram Se/g creatinine) than healthy controls. The decrease of the urinary Se concentration (microgram Se/g creatinine) observed with the increase in age of heroin abusers may be due to the higher exposure to heroin with increased age. No significant differences (P > 0.100) of urinary Se concentrations (both as microgram Se/l and microgram Se/g creatinine) are observed between heroin abusers during methadone treatment and heroin abusers who have stopped taking the drug, with respect to healthy controls.

Adult↗

PubMed1993

Urinary selenium concentrations.

Urinary selenium concentrations are used as an indicator of selenium status. A strong correlation has been established between dietary selenium and daily urinary selenium excretion in a wide range of populations from all over the world with different dietary selenium intake. Data on urinary selenium concentrations in healthy individuals and patients with different pathological conditions are reviewed. Selenium excretion rates of 20-200 micrograms/day are not associated with deficiency or toxicity problems. Urinary Se excretion is decreased in children, elderly people, and pregnant women. Workers exposed to heavy metals, and cancer patients, have higher and lower urinary Se concentrations, respectively, than control groups. The trimethylselenonium ion, a minor metabolite of Se in urine, assumes a significant role only in the detoxification of excess Se intake. Studies of bioavailability and balance show the important role of the kidneys in homeostatic regulation of Se.

Humans↗

PubMedDate not supplied

[Concentrations of Na, K, Ca, and P in serum from a representative sample of the Canary Islands population].

As part of the nutritional survey of the Canary Islands (ENCA-1998), the concentrations in serum of Na, K, Ca and P were determined in 395 individuals representing the population of the Canary Islands. The concentrations were found to be within the reference intervals described for the healthy population. Differences were observed in the mean concentrations depending on the island of residence. Thus, individuals on the island of Tenerife showed higher levels of natremia and calcaemia (p < 0.05) than those on the other islands. The islanders of La Palma have the highest (p < 0.05) and lowest (p < 0.05) concentrations of K and Ca, respectively, whereas those living on the easternmost islands have the highest levels of phosphataemia. No differences were detected in the mineral levels by sex. Phosphataemia levels fall (p < 0.05) in line with socio-economic levels. Females under the age of 18 present lower levels of natremia (p < 0.05) than others while males over the age of 35 present higher levels of kalaemia (p < 0.05). No important age-related differences were found in calcaemia and individuals under the age of 18 had lower levels of phosphataemia (p < 0.05) than the remainder. Highly significant relationships were found between Na and K and between Ca and P, thus confirming existing physiological relationships. Smoking had no effect on the serum levels of the elements under study. Those individuals reporting an intake of more than seven beers and seven shots of spirit per week presented lower levels of calcaemia and natremia than the rest (p < 0.05). With wine consumption, an increase in kalaemia and a significant reduction (p < 0.05) in the Na/K ratio were detected. Individuals drinking only tap water had higher levels (p < 0.05) of natraemia and kalaemia, with lower levels (p < 0.05) of calcaemia and the Na/K ratio than those drinking bottled water. The Ca/P ratio was significantly reduced (p < 0.05) with physical exercise.

Adolescent↗

PubMedDate not supplied

[Haematologic parameters in opiate addicts].

Levels of haemoglobin, haematocrit, number of red cells and leukocytes, haematological index (MCV, MCH, MCHC, DEI, MPV), sedimentation rate, iron, parameter related to accumulation and transport of iron (transferrin, ferritin, iron binding capability, transferring saturation index) and platelets were determined in blood samples of opiate addicts and they were compared with these results obtained in a control group. For both sexes, the levels of haemoglobin, haematocrit, iron and platelets were similar in the control groups and opiate addicts. Opiate addicts females presented a number of red cells and platelets higher and lower respectively than the correspond values of the control group. The haematological index in opiate addicts were higher than the values in the control groups for overall and considering males and females independently. The levels of ferritin in opiate addicts males were higher than these levels found in control groups, occurring the contrary in the females. Opiate addicts males and females included in the methadone maintenance treatment program (MMTP) presented similar values of haemoglobin, haematocrit, number of red cells and leukocytes than the corresponding opiate addicts non-included in MMTP, except opiate addicts males, who showed lower haematocrit values.

Adult↗

PubMedDate not supplied

[Application of multivariate analysis to the serum mineral and trace element content on differentiation of healthy subjects].

OBJECTIVE: Serum concentrations of Na, K, Ca, Mg, Fe, Cu, Zn, Se, Mn and P were determined in apparently health individuals representing of the population of the Canary Islands. Multivariate analysis was applied on the data matrix in order to differentiate the individuals according several criteria such as gender, age, island and province of residence, smoking and drinking habits and physical exercise. SUBJECTS AND METHODS: 395 serum samples (187 men and 208 women) were analyzed mean age of 38.4 +/- 20.0 years. Individuals data about age, gender, weight, height, alcohol consumption, smoking habits and physical exercise were recorded using standardized questionnaires. The determination of minerals was carried out by flame emission spectrometry (Na and K) and atomic absorption spectrometry with flame air/acetylene (Ca, Mg, Fe, Cu, Zn), hybride generation (Se) and graphite furnace (Mn). The P was determined by a colorimetric method. RESULTS: The sex and age of individuals influenced on the serum concentrations of some minerals, Cu and Fe, and P and Se, respectively. The island of residence influenced the mean concentrations of the most the minerals analysed. The smoking and drinking habits do not seem to influence the mean contents of the minerals in an important manner. Physical exercise had significant influence on the P, Cu and Mn concentrations in serum. The water for consumption influenced on the serum concentrations of the electrolytes and Ca and Mg, but it did not affect the concentrations of the trace elements. Applying discriminant analysis the individuals lower 18 years were reasonably well differentiated (89% of the individuals correctly classified) from the rest of individuals. A tendency for differentiation of individuals according to the island of residence was also observed. CONCLUSIONS: A low differentiation of the individuals according to the sex, province or island or residence and habits or life style was observed after application of multivariate analysis techniques. However, the adults were reasonably differentiated from the children and adolescent, and the inhabitants of Lanzarote and La Palma tend to separate from the rest of the individuals of their province.

Adolescent↗

PubMedDate not supplied

Stability of cannabinoids in urine in three storage temperatures.

Stability of cannabinoid compounds in urine samples were evaluated using several storage temperatures. Appreciable losses (> 22.4 percent) were observed in some urine samples, after being stored at room temperature for 10 days. Lower losses (8.1 percent) were observed when the urine samples were refrigerated for 4 weeks. The behavior of urine samples depended on the analyzed urine. This could be due to the different stability of the cannabinoids present in each urine sample. Important losses of 8.0 +/- 10.6, 15.8 +/- 4.2, and 19.6 +/- 6.7 percent were found when the urine samples were frozen during 40 days, 1 year, and 3 years, respectively. Average losses (> > 5 percent) can be observed after one day which could mainly be due to the decrease of the solubility of 11-nor-U9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) or adsorption process of cannabinoid molecules to the plastic storage containers.

Adsorption↗