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Biomedical subjects

A Gil

Publications and source records attributed to A Gil.

At least 217 records · Page 12Linked to original sources
PubMed1995

Protein v. enzymic protein hydrolysates. Nitrogen utilization in starved rats.

The present study was carried out to compare the effects of four isoenergetic and isonitrogenous diets on the N utilization, total serum protein concentration and serum amino acid profile in starved rats at weaning. These diets differed only in the molecular form of two milk proteins (whey protein and casein), which were either native or partly hydrolysed. Male Wistar rats at weaning were fasted for 3 d and then refed with one of the four diets for 48 h. No differences were observed in the body weight gain, protein digestibility and total serum protein concentration between groups after the refeeding period and all the N balances were positive. N retention was higher in the two groups of rats given the protein-hydrolysate-based diets compared with those given the intact-protein-based diets. This was associated with a lower urinary N excretion in rats, given the whey-protein-hydrolysate and the casein-hydrolysate diets. Despite this fact, the serum amino acid pattern of rats given the hydrolysed protein diet was very similar to that of those given the corresponding native protein diet. In conclusion, we have proved that enzymic hydrolysates from milk proteins have equivalent effects to native proteins in recovery after starvation in rats at weaning, on N absorption, total serum protein concentration and serum amino acid profile, and even give a higher N retention. We did not observe any harmful effect in using protein hydrolysates instead of native proteins.

Amino Acids↗
PubMed1994

Dental lead levels in the Galician population, Spain.

The aim of this study was to investigate tooth lead concentrations in a Spanish population living in Coruña, Spain. A total of 220 teeth were analysed using a microwave oven digestion procedure and lead content was measured by atomic absorption spectrometry. Samples were classified according to age, sex, type of tooth, cause of extraction and place of residence. Tooth lead levels followed a logarithmic-normal distribution. The general geometric mean was 10.36 micrograms/g of tooth. There was a significant increase in teeth lead levels with advancing age. Permanent teeth showed higher values (13.09 +/- 1.07 micrograms/g, mean +/- S.E.M.) than deciduous teeth (3.96 +/- 1.07 micrograms/g). However, no differences were found between sexes. High lead concentrations were detected in pathological teeth, particularly in those with periodontal pathology, suggesting a relation between lead levels and dental disease. Nevertheless, teeth with caries did not show any significant lead increase. People living in urban areas of the coast had the highest lead teeth contamination. This is the first study in Spain which describes the tooth lead levels as a marker of lead exposure.

Adolescent↗
PubMed1994

[Evaluation of immunogenicity and safety in healthy adults of an inactivated anti-hepatitis A vaccine].

BACKGROUND: The evaluation of the safety and immunogenicity of an inactivated vaccine against the hepatitis A virus (HAV) in healthy adults was performed. METHODS: A descriptive clinical trial was carried out including a population of 100 healthy subjects of ages from 19 to 25-years. The subjects were intramuscularly injected (deltoid muscle) with an inactivated vaccine against hepatitis A (720 units ELISA) following a schedule of 0.1 months and a booster dose at 6 months. The titers of anti HAV antibodies were determined by the ELISA method prior to vaccination and following the administration of each doses. The safety of the vaccine was also parallelly evaluated after each doses from both a local and systemic point of view. RESULTS: With respect to safety, local signs and symptoms were presented in 34.6% of the subjects while systemic signs and symptoms were observed in 6.8% following administration of the 3 doses. At one month of the first doses 95.8% of the subjects had seroconverted (> or = 20 mUI/ml) with this rising to 100% at one month of receiving the second and third doses. The geometric mean of the antibody titer one month after having received each of the three doses was 158 mUI/ml, 832 mUI/ml and 4,135 mUI/ml, respectively. CONCLUSIONS: The vaccine was well tolerated and demonstrated great safety with a 100% rate of seroconversion following the primary cycle with two doses. The administration of the reminder doses at 6 months increased the antibody titer five fold after the primary cycle.

Adult↗
PubMed1994

Casualties in Acapulco: results of a study on alcohol use and emergency room care.

This article reports the results of an emergency room study carried out in 1987 in three hospitals in Acapulco, Mexico. All patients were interviewed and breath tested for alcohol consumption. The data were analyzed using the case-control methodology. Cases were falls, motor vehicle accidents, fights and assaults, and home accidents. The control group included patients for whom accidents are less frequently reported as alcohol related, i.e., those reporting work place accidents, animal bites and recreational accidents. For positive breathalyzer readings (> or = 10 mg/100 ml of blood alcohol), the odds ration and 95% confidence intervals were statistically significant for falls, 3.45 (1.23-9.66); motor vehicle accidents, 3.85 (1.21-12.01); and fights and assaults, 5.23 (2.36-12.95). The association was non-significant for home accidents, 0.78 (0.20-2.98). Possible biases of this approach are discussed and recommendations are made for selecting better controls for future emergency room studies.

Accidental Falls↗
PubMed1994

Albumin excretion rate and metabolic modifications in patients with essential hypertension. Effects of two angiotensin converting enzyme inhibitors.

A prospective randomized, double-blind, double-dummy study investigated the effects of two angiotensin converting enzyme (ACE) inhibitors on urinary albumin excretion in nondiabetic patients with mild to moderate essential hypertension. At the end of a 4-week placebo run-in period, 36 patients were randomly allocated to receive a 12-week course of treatment with quinapril (10, 20, or 40 mg) once daily or captopril (25, 50, or 75 mg) twice daily. Seventeen patients in each group completed the study. The mean change in mean blood pressure for patients taking quinapril (mean dose 32 mg/24 h) was -5 mm Hg (P = .002), and for patients taking captopril (mean dose 132 mg/24 h), -9 mm Hg (P = .002). The baseline urinary albumin excretion rate in both groups was (mean +/- EEM) 57 +/- 7 micrograms/min. Fifteen patients in the quinapril group and 12 patients in the captopril group had baseline albumin excretion rates of more than 20 micrograms/min. Mean urinary albumin excretion decreased in patients treated with quinapril from 55 to 33 micrograms/min (mean decrease 22 micrograms/min, 95% confidence interval [CI], 1 to 43 micrograms/min; P = .031) and with captopril from 59 to 41 micrograms/min (mean decrease 18 micrograms/min, 95% CI, 3 to 32 micrograms/min; P = .025). No significant modifications were observed in serum lipid concentrations, serum and urinary electrolytes, and magnesium or phosphorus metabolism. Mean urinary calcium excretion decreased in the quinapril-treated group (from 219 to 188 mg/24 h; P = .023) but not in the captopril group (from 264 to 267 mg/24 h).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Nutritional value and antigenicity of two milk protein hydrolysates in rats and guinea pigs.

Two milk protein (whey protein and casein) hydrolysates were obtained by enzymatic hydrolysis. In the casein hydrolysate, an ultrafiltration stage was performed to remove all the peptides with molecular weights > 2500. A nutritional value study of both hydrolysates was undertaken. No differences were found between the native proteins and their enzymatic hydrolysates. Neither the enzymatic hydrolysis nor the heat treatments used affected the nutritional value of the protein sources. The two hydrolysates were studied for antigenic properties. The enzymatic hydrolysis of the whey protein concentrate followed by a thermal treatment at 90 degrees C for 10 min reduced significantly its antigenicity. However, the in vivo allergenicity tests showed some positive reactions in both systemic anaphylaxis and passive cutaneous anaphylaxis. The casein hydrolysate, after being ultrafiltered, was devoid of sensitizing capacity by the oral route and was also ineffective in producing local or systemic anaphylaxis in previously sensitized animals, as shown by in vivo assays.

Amino Acids↗
PubMed1994

Role of nucleotides in intestinal development and repair: implications for infant nutrition.

Dietary sources of nucleotides may be conditionally essential nutrients. Rapidly growing tissues such as the intestinal epithelium and lymphoid cells lack significant capacity for de novo synthesis of nucleotides and require exogenous sources of purine and pyrimidine bases. Dietary purines are not significantly incorporated into hepatic nucleic acids, but pyrimidines are. Both are taken up by intestinal cells with excess purines converted to uric acid. Nucleotides are important for normal development, maturation and repair of the gastrointestinal tract. Human milk is the best source of nucleotides for young infants because cow's milk is lacking in nucleotide content. It is likely that infant formulas should have sources of nucleotides added to more closely duplicate human milk and provide these substrates for maximal intestinal development and repair.

Animals↗
PubMed1994

Effect of dietary nucleotide supplementation on diarrhoeal disease in infants.

The effects of a nucleotide-supplemented formula on diarrhoeal disease was studied in 141 infants (group 1) who belonged to the low socioeconomic stratum; 148 controls (group 2) received the same formula but unsupplemented. Group 1 experienced less episodes of diarrhoea (109 versus 140), including less first episodes (74 versus 102; chi-square = 8.19, p < 0.004; odds ratio 2.01) and for a lesser number of days (807 versus 996 days); 45.0% and 31.1% of infants in groups 1 and 2, respectively, never developed episodes of diarrhoea. There were no differences in the clinical characteristics of the episodes or in the enteropathogens isolated from symptomatic or asymptomatic infants. The mechanisms through which nucleotides decrease the incidence of diarrhoeal disease in infants remain unclear.

Chile↗
PubMed1994

Lipoprotein changes in small-for-gestational-age infants fed nucleotide-supplemented milk formula.

We determined the effect of supplementing milk formula with nucleotides on plasma lipoproteins in small-for-gestational-age infants: 21 infants were fed a nucleotide-supplemented formula and 20 infants were fed the same nucleotide-free formula. On days 0, 3 and 7 after birth, major plasma lipoprotein fractions were analyzed for apolipoprotein and lipid composition. Compared with the control group, the group receiving nucleotides had increased total apoprotein concentrations in all lipoproteins as well as increased apo A-I in high-density lipoproteins and very low-density lipoproteins, and apo B-100 in very low-density lipoproteins and low-density lipoproteins. Very low-density lipoprotein cholesterol, low-density lipoprotein cholesterol and very low-density lipoprotein triglycerides increased in parallel to the changes in apoproteins. The cholesterol ester to unesterified cholesterol ratio was increased in low-density lipoproteins and, particularly, in high-density lipoproteins. These data support the hypothesis that lipoprotein metabolism in small-for-gestational-age infants is affected by dietary nucleotide supplementation, enhancing lipoprotein synthesis or secretion. Cholesterol esterification capacity paralleled the apo A-I increase, in agreement with the cofactor role of apo A-I on lecithin: cholesterol acyltransferase.

Apolipoproteins↗
PubMed1994

Effect of dietary nucleotides on small intestinal repair after diarrhoea. Histological and ultrastructural changes.

The effects of specific nutrients on intestinal maturation and repair after injury are practically unknown. The purpose of this work was to study the effects of dietary nucleotides on the repair of the intestinal mucosa after chronic diarrhoea induced by a lactose enriched diet in the weanling rat. One group of weanling rats was fed with a standard semipurified diet (control group), and another group was fed with the same diet containing lactose as the only soluble carbohydrate (lactose group). After 14 days the lactose group was allowed to recover for four weeks with the control diet (lactose-control group) or with the control diet supplemented with AMP, GMP, IMP, CMP, and UMP 50 mg/100 g each (lactose-nucleotide group). The control group was divided into two subgroups, which were fed with the control diet and the nucleotide supplemented diet for the same period (control-control group and control-nucleotide group). The lactose diet induced diarrhoea after 24 hours of feeding. Two weeks later there were changes in intestinal structure with loss of enterocyte microvillar surface, significant lymphocyte infiltration, supranuclear cytoplasmic vesiculation, decreased number of goblet cells, and enlarged mitochondria with low density and few cristae. After recovery from diarrhoea, animals fed the nucleotide enriched diet showed an intestinal histology and ultrastructure closer to that of the normal control group. Mitochondrial ultrastructure was closer to normal in comparison with the lactose-control diet group. In this second group the number of goblet cells as well as the villous height/crypt depth ratio was reduced and the number of intraepithelial lymphocytes increased compared with the nucleotide supplemented group. These results suggest that dietary nucleotides may be important nutrients for intestinal repair.

Animals↗
PubMed1994

Value of immunologic testing in stroke patients. A prospective multicenter study.

BACKGROUND AND PURPOSE: The aims of this prospective and multicenter study were to determine the frequency of anticardiolipin and antinuclear antibodies in an unselected ischemic and hemorrhagic stroke population and to evaluate the clinical significance of these autoantibodies. METHODS: Over a 1-year period, we collected plasma from 481 consecutive patients with ischemic or hemorrhagic stroke attending four different hospitals. Blood (10 mL) was drawn from each subject into a citrated glass tube. Plasma was obtained immediately by centrifugation and was stored at -70 degrees C until use. Concentrations of IgM and IgG anticardiolipin antibodies were measured at room temperature in normal (not heat-treated) plasma by standardized enzyme-linked immunosorbent assay. All sera were treated by indirect immunofluorescence on mouse liver and kidney sections for antinuclear antibodies. RESULTS: A total of 481 patients (325 men, 156 women) 16 to 90 years in age (mean age, 61 years) were studied. Anticardiolipin antibodies were present in 5 of 481 (1.04%) patients. One patient was IgG positive and four patients were IgM positive. Of 481 patients, 35 (7.2%) were positive for antinuclear antibodies. Anti-DNA antibodies were not demonstrable in any patient. CONCLUSIONS: The frequency of anticardiolipin antibodies in a heterogeneous stroke population is possibly lower than reported. The routine screening of anticardiolipin and antinuclear antibodies in a stroke population is of questionable value.

Adolescent↗
PubMed1994

Dietary nucleotides influence lipoprotein metabolism in newborn infants.

Nucleotide supplementation of adapted-milk formulas may be of interest for infant nutrition because nucleotides are involved in the synthesis of proteins and other macromolecules such as phospholipids, and thereby facilitate lipoprotein synthesis. To determine whether dietary nucleotides influence plasma lipoproteins in newborns, we have studied the plasma-lipoprotein concentrations and the composition of the major lipoprotein fractions during the first week of life in two groups of preterm infants fed formulas differing only in their nucleotide content. For comparison, two groups of term infants were studied under the same conditions. Lipoproteins were isolated by density ultracentrifugation, and the lipid and protein content were determined by standard methods; apolipoprotein A-I was determined immunologically. Nucleotide supplementation of formula in preterm infants increased all plasma lipoprotein concentrations. In addition, an increase in the plasma esterification rate was observed. However, total cholesterol concentrations were unchanged. The changes in lipoproteins concentrations were due mainly to an increase in apolipoprotein content. Nucleotides added to formulas affected term-infants' lipoproteins significantly less than to preterm infants. These findings suggest that dietary nucleotides may enhance the synthesis of lipoproteins during the early neonatal period, especially in preterm infants.

Animals↗
PubMed1994

Changes in ganglioside and sialic acid contents of goat milk during lactation.

The ganglioside content of goat milk has been determined from d 1 after parturition to d 60 of lactation. Marked changes occurred in milk over the course of lactation; the highest ganglioside content occurred in d-1 colostrum and then decreased to the end of the period studied. At least seven different ganglioside species were detected; three gangliosides containing sialyllactosylceramide accounted for 66 to 92% of the total lipid-bound sialic acid; this result reflected a very simple core structure of goat milk gangliosides. The most abundant ganglioside, II3(N-acetylneuraminic acid)2-lactosylceramide, was about 35 to 56%. The sialic acid content exhibited a trend similar to that of gangliosides; during early lactation sialic acid content was higher than in mature milk. Fat, protein, and total solids were high at initiation of lactation and decreased thereafter. However, lactose content remained almost unchanged during the period studied.

Animals↗
PubMed1994

Sex hormones in chronic systemic lupus erythematosus. Correlation with clinical and biological parameters.

Sex hormones may play a major role in the pathogenesis and course of systemic lupus erythematosus (SLE). OBJECTIVE--To evaluate the immunoregulatory effect of gonadal steroids in SLE and their mechanisms of action, and to establish a correlation with the clinical and biological activity. DESIGN--Cross-sectional study of a cohort with SLE. SETTING--Outpatient SLE clinic. PATIENTS--27 patients with chronic SLE, 14 were fertile women, 8 postmenopausal women and 5 men. MEASUREMENT--Serum gonadotropins (FSH, LH), prolactin (PRL), progesterone (PG), testosterone (T), estradiol (E2) and total urinary estrogens (UE) were studied in SLE patients and in 35 healthy controls of similar age and sex. Blood and urine samples of several days of the study cycle were obtained for hormonal assay. RESULTS--An increased LH activity was observed in all groups of patients. There were no changes in serum T levels, but absence of steroid therapy increased their levels in fertile women. A decrease in E2 values in the fertile women was observed, but total UE was similar to those in controls. This suggests an alteration in intermediate estrogen metabolism. Men with SLE showed a higher levels in PG and UE than controls. Also, in both groups of women on steroid treatment, a decrease of PRL was observed compared to the controls. In the fertile women in luteal phase, there was a decrease in PG. In the fertile women with higher clinical activity in the midcycle phase, and those with higher biological activity in the luteal phase, a decrease in serum E2 was seen. CONCLUSIONS--Our results support the hypothesis that there is an alteration of intermediate metabolism of the estrogens and of the testosterone. As well, a lower production of PRL during steroid treatment, and a lower production of PG may be important contributing factors in immunomodulation of SLE. Mechanism for this action should be mediated through a stimulation of the gonadotropins as LH.

Adolescent↗
PubMed1993

Microwave oven digestion procedure for atomic absorption spectrometry analysis of bone and teeth.

The purpose of this study was to develop a new method for determination of the mineral element in teeth and bone using a microwave digestion procedure coupled to atomic absorption spectrometry. Samples were ashed at 450 degrees C for 4.5 h and subsequently digested in a microwave oven at maximum power (600 W) for 10 s using a Teflon closed Parr bomb. This method permits the rapid dissolution of the biological samples, avoiding operations such as slicing and cutting which often introduce alterations in sample homogeneity and may contribute to their contamination. The analysis of Na, K, Ca, Mg, Fe, Zn, Ba, Cd and Pb showed good reproducibility, precision and accuracy as compared with the certified values for the IAEA H-5 animal bone. Average concentration for those elements in permanent teeth obtained from children aged 11-18 years by orthodontics are given.

Adolescent↗