Search PubMed⌕ Search

Biomedical subjects

A Gil

Publications and source records attributed to A Gil.

At least 307 records · Page 17Linked to original sources
PubMed1987

Position-dependent sequence elements downstream of AAUAAA are required for efficient rabbit beta-globin mRNA 3' end formation.

We previously demonstrated that a critical 35 bp region 3' of the AAUAAA is required for rabbit beta-globin mRNA 3' end formation. Recently, we synthesized and tested sequence elements derived from this region. Here, we report that a GU-rich and a U-rich sequence element are both required for efficient rabbit beta-globin mRNA 3' end formation. The efficiency of processing is restored to the wild-type level when the two elements are placed together and is greatly diminished when only one element is present. The level of 3' end formation is also decreased when the distance between the two elements is expanded. These results demonstrate that the GU-rich and U-rich elements function synergistically to restore efficient mRNA 3' end formation and that they most likely form a single requisite sequence 3' of the AAUAAA. Furthermore, we show that the effect of the GU-rich and U-rich sequence elements is position-dependent.

Animals↗
PubMed1987

Changes in the fatty acid composition of plasma and red blood cell membrane during the first hours of life in human neonates.

The objective of this work was to examine the changes in the fatty acid profiles of plasma lipid fractions and red blood cell membrane phospholipids in newborn infants during the first 6-8 h of life. Methyl esters of fatty acids from plasma free fatty acids and phospholipids and from membrane phosphatidylethanolamine, phosphatidylcholine and sphingomyelin for cord blood (n = 20) and venous blood (n = 19) were analyzed by GLC. Important changes were observed in plasma fatty acids. Palmitic and palmitoleic acid increased from birth to 6-8 h of age for both free fatty acids and phospholipids. Palmitic acid also increased in membrane phosphatidylcholine and phosphatidylethanolamine. In the former, stearic acid declined whereas oleic and docosatetraenoic acids increased. Phosphatidylethanolamine and sphingomyelin were less affected than phosphatidylcholine probably because the internal location of the two first fractions in erythrocyte membrane. Polyunsaturated fatty acids dropped slightly during the first hours of life in most lipid fractions. This may be a consequence of the interruption of placental fatty acid supply and the limited capacity of the newborn to desaturate their essential fatty acid tissue stores.

Erythrocyte Membrane↗
PubMed1987

Coagulation abnormalities in patients with eosinophilia.

Haematological variables in patients with eosinophilia and in healthy control subjects were studied in order to determine whether there were abnormalities in the coagulation system in patients. We found significantly elevated levels of fibrinogen, fibrin degradation products, platelet number and beta-thromboglobulin in patients. The abnormalities were not related to the causes of eosinophilia nor to its severity. This lack of correlation could be due to the heterogeneity of human peripheral blood eosinophils.

Blood Coagulation↗
PubMed1987

Protein composition of human milk in relation to mothers' weight and socioeconomic status.

In the past few years there has been a resurgence of interest in the protein composition of human milk. Up to now the influence of maternal diet and of the mothers' nutritional status on the protein composition of human milk have not been fully clarified. We have evaluated the relationship between the mothers' socioeconomic status and weight and the protein composition of human milk. Protein fractions were determined by a polyacrylamide gel electrophoresis method in 181 samples of human milk obtained from voluntary donors. Samples were classified according to the time of lactation and in relation to the socioeconomic status and to the weight of the lactating women. Total protein and non-protein nitrogen decreased with advancing lactation but there were no differences among the socioeconomic and weight groups of mothers who were considered. beta- and kappa-caseins fell during lactation and beta-casein was significantly increased in the milk of the upper socioeconomic class with respect to that of the low one. alpha-lactalbumin increased from transitional to mature milk (16-30 d) and then declined. The milk from the low socioeconomic group presented the lowest levels of this protein. Lysozyme increased during lactation, whereas lactoferrin decreased. Both proteins were significantly influenced by the mothers' socioeconomic status; the highest concentrations for these proteins were found in the milk of the low socioeconomic group. Deficit or excess of mothers' weight did not influence the levels of the different protein fractions of human milk.

Body Weight↗
PubMed1987

[Study of infant milk formulas present on the Spanish market and its adaptation to the recommendations of the European Society of Gastroenterology and Pediatric Nutrition].

The aim of this study was to investigate energy as well as the protein and mineral composition of milk formulas available on the Spanish market. We studied 20 milk formulas, 14 of which were adapted milk formulas intended for feeding newborns during the first 4-6 months of life and the other 6 ones were follow-up milk formulas. Determinations of energy, total protein, osmolality, sodium, potassium, chloride, phosphorus and calcium were performed by adiabatic calorimetry, cryoscopy, flame photometry, photocolorimetry and flame atomic absorption spectrophotometry respectively. Experimental energy in all formulas was higher than that determined by nutrient contents and conversion factors. Three of the adapted formulas presented higher values of protein than those recommended by ESPGAN and some of them also high levels for sodium total electrolytes. However, the estimated renal solute load for each of the formulas was lower than the minimum renal concentration ability. All formulas, except one, showed normal values for calcium and the contents of phosphorus, were within normalcy. All the follow-up formulas agreed with the ESPGAN recommendations related with protein and mineral composition.

Energy Intake↗
PubMed1986

Changes in the protein fractions of human milk during lactation.

The changes in the absolute and relative contents of alpha- and kappa-caseins, lactoferrin, alpha-lactalbumin, serum albumin and lysozyme in human milk have been studied through the period of lactation. Protein fractions of 209 samples were analyzed by a discontinuous polyacrylamide gel electrophoresis method. beta- and kappa-caseins decreased from colostrum to mature milk although their relative percentages remained constant. They accounted for 12-15 and 9-13% of the total protein in human milk, respectively. Lactoferrin decreased in absolute and relative amounts with advancing lactation. This protein represented 32-19% of the human milk proteins. alpha-Lactalbumin slightly decreased from colostrum to transitional milk but there was an increase in mature milk by 16-30 days. The percentages of this protein in colostrum and mature milk were approximately 23 and 30%, respectively. Serum albumin also decreased with advancing lactation, but the differences between transitional and mature milk were not statistically significant. Lysozyme increased from colostrum to mature milk both in relative and absolute amounts. Colostrum contained about 262 micrograms/ml, and mature milk 1,246 micrograms/ml, representing 1.5 and 12.1% of total milk proteins.

Animals↗
PubMed1986

Combination chemotherapy of cisplatin and 5-FU in advanced colorectal carcinoma.

Thirty-two patients with advanced colorectal carcinoma were treated with cisplatin (100 mg/m2) by infusion over 24 hours on Day 1 and 5-FU (1000 mg/m2/day) by infusion over 24 hours on Days 2-6 every 28 days. Ten of the 32 patients had received prior chemotherapy consisting of either 5-FU alone or 5-FU combination regimens. Objective response was observed in 13 patients (two complete and 11 partial responses). Another 11 patients had stabilization of disease. The overall median survival time in this study was 9.53 months. Toxicity was generally mild and tolerable. The response rate found in this study indicated that continuous infusion of cisplatin-5-FU administered at this dose and schedule was moderately active in advanced colorectal carcinoma.

Adult↗
PubMed1986

Effect of dietary nucleotides on the plasma fatty acids in at-term neonates.

Non-protein nitrogen from human milk is presently being implicated in neonatal physiology. Human milk contains relatively high amounts of nucleotides which are practically absent in cow's milk and milk formulas. These compounds have been related to normal growth and cellular immunity in animals in early life. The aim of this study was to investigate the effects of dietary nucleotides on the plasma fatty acid pattern in term neonates during the first month of life. Twenty-six infants were fed human milk, 35 a milk formula and 23 the same formula supplemented with cytidine, adenosine, guanosine, uridine and inosine 5'-monophosphates in similar quantities to those determined in human milk. Plasma polyunsaturated fatty acids with more than 18 carbons of the omega 6 family were significantly increased in infants fed with the nucleotide-supplemented milk formula with respect to those fed the milk formula, whereas no differences could be detected between the human milk-fed and the nucleotide milk formula-fed ones. These results suggest that dietary nucleotides may be involved in the conversion of linoleic acid to longer chain polyunsaturated fatty acids during early life.

Aging↗
PubMed1986

[Branched-chain amino acids: indicators of fetal nutritional status].

Both nutritive state for Rohrer's ratio (Rr) and serum aminoacids (aa) (Chromatospek J-180) of the umbilical cord have been analyzed and correlated in two groups of the newborns: G-I (n: 12) preterm infants with an adequated weight for their gestational age (Re greater than 10 percentile) and G-II (n: 8) small for-date term infants (Rr less than 10 p). Ratios of the serum aa (total aa, no essential aa, NE/E, Ala/Thr, Whitehead's ratio (Wr), Ala/Leu, Ala/BCA, Gly/Val, Ser + Gly + Ala/BCA) were more elevated in G-II than those one of the G-I. We have shown a single correlation between Wr and Rr (r. much greater than 0.48, p less than 0.025) in G-I and between BCA Rr (r. much greater than 0.88, p less than 0.0025) in G-II; furthermore, we have proved a good correlation between the week of gestation and sum of BCA (r. much greater than 0.53, p less than 0.05) in the former that have not been observed among the latter which had BCA more increased than G-I (p less than 0.050). Some speculations about the role that could play the BCA in the energetic metabolism of the small-for-date infants are made; on the other hand, the BCA can give help to distinguish between premature or pseudopremature among infants weighing 2.500 g or less a birth.

Amino Acids, Branched-Chain↗