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P Mata

Publications and source records attributed to P Mata.

At least 37 records · Page 2Linked to original sources
PubMed1996

Effect of dietary fat saturation on LDL oxidation and monocyte adhesion to human endothelial cells in vitro.

Forty-two healthy men and women were subjected to four consecutive dietary periods differing in the fat content of saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), and polyunsaturated fatty acids (n-6) [PUFA(n-6)] and (n-3) [PUFA(n-3)]. Plasma lipids, vitamin E, and in vitro LDL oxidation were examined during each period. Adhesion of human monocytes to cultured human endothelial cells was used as a functional test to identify differences in the biological properties of LDL from each dietary period. Consumption of an SFA-rich diet resulted in higher LDL cholesterol (4.06 +/- 0.85 mmol/L, P < .05) than did consumption of MUFA- (3.59 +/- 0.75 mmol/L), PUFA(n-6)- (3.44 +/- 0.77 mmol/L), or PUFA(n-3)- (3.31 +/- 0.8 mmol/L) rich diets. HDL cholesterol was lower during both PUFA-rich diets (1.24 +/- 0.28 and 1.27 +/- 0.28 mmol/L for n-6 and n-3, respectively) than during the SFA-(1.32 +/- 0.36 mmol/L) and MUFA- (1.32 +/- 0.34 mmol/L) rich diets. LDL resistance to copper-induced oxidation, expressed as lag time, was highest during the MUFA-rich diet (55.1 +/- 7.3 minutes) and lowest during the PUFA(n-3)- (45.3 +/- 7 minutes) and SFA- (45.3 +/- 6.4 minutes) rich diets. LDL induction of monocyte adhesion to endothelial cells was lower during the MUFA-rich diet than the other periods. The highest monocyte adhesion was obtained during the PUFA(n-3) and SFA dietary periods. In conclusion, an MUFA-rich diet benefits plasma lipid levels compared with an SFA-rich diet. Furthermore, this diet results in an increased resistance of LDL to oxidation and a lower rate of monocyte adhesion to endothelial cells than the other dietary fats examined.

Adult↗
PubMed1995

Gene-diet interaction in determining plasma lipid response to dietary intervention.

It has long been known that there is an extremely high degree of variability in both human and nonhuman primates in terms of low density lipoprotein cholesterol (LDL-C) lowering in response to restriction of dietary saturated fat and cholesterol. In this regard we have reviewed the current knowledge regarding the gene-diet interaction in relation to plasma lipid response to dietary intervention. Several candidate gene loci have been examined in humans: apolipoprotein (apo) A-I, apo A-IV, apo B, apo C-III and apo E, as well as lipoprotein lipase (LPL). Several mutations at these loci have been found to be associated with responsiveness. We and others have documented that subjects carrying the apo E4 allele are more responsive with regard to LDL-C lowering in response to dietary fat and cholesterol restriction than subjects carrying the apo E3 or apo E2 alleles, whereas some studies report no association of apo E phenotypes with lipid response to some dietary interventions. Our own meta-analysis indicates that apo E genotype effects are modulated via alterations of amount and type of dietary fat. We have also documented that subjects carrying the common glutamine for histidine mutation at amino acid 360 of apo A-IV are significantly less responsive in terms of LDL-C lowering than subjects with the normal apo A-IV genotype is modulated via changes in dietary cholesterol. In addition, we have documented that the common G/A mutation within the promoter region of the apo A-I gene is associated with greater responsiveness of LDL-C to dietary fat alterations. The XbaI and insertion/deletion polymorphisms at the apo B gene locus and the HindIII restriction fragment length polymorphism (RFLP) at the LPL locus have also been associated with diet responsiveness. Therefore, in humans these gene loci account for a significant portion of the variability in plasma lipid response to dietary alterations.

Animals↗
PubMed1994

ApoA-IV phenotype affects diet-induced plasma LDL cholesterol lowering.

The National Cholesterol Education Program (NCEP) recommends that dietary total fat, saturated fat, and cholesterol intake be reduced to < or = 30% of calories, < 10% of calories, and < 300 mg/d, respectively (step 1 diet), in the general population to reduce plasma low-density lipoprotein cholesterol (LDL-C) levels and heart disease risk. We examined the LDL-C-lowering response to such a diet (26% fat, 8% saturated fat, and 201 mg/d cholesterol) compared with an average American diet (39% fat, 15% saturated fat, and 435 mg cholesterol/d) in 153 subjects using diet periods of 4 through 24 weeks for each diet phase. The mean LDL-C reduction was 13% in men (n = 93) and 7% in postmenopausal women (n = 60). The effect of apolipoprotein (apo) A-IV phenotype on responsiveness was examined. LDL-C lowering in men was significantly (P < .005) less (7%) for 17 apoA-IV (1/2) subjects than for 76 apoA-IV (1/1) subjects (16%). In women, 7% lowering was observed in both 12 apoA-IV (1/2) subjects and 48 apoA-IV (1/1) subjects. ApoA-IV phenotype had a significant effect on plasma high-density lipoprotein cholesterol levels during both dietary periods; women carrying the apoA-IV-2 allele had higher levels than those homozygous for the apoA-IV-1 allele. The opposite was true for triglyceride levels, but only during the period when the subjects consumed the high-fat, high-cholesterol diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Effect of apolipoprotein E phenotype on diet-induced lowering of plasma low density lipoprotein cholesterol.

The National Cholesterol Education Program (NCEP) has recommended that dietary total fat, saturated fat, and cholesterol intake be reduced to < or = 30% of calories, < 10% of calories, and < 300 mg/day, respectively (Step 1 diet) in the general population to reduce plasma low density lipoprotein (LDL) cholesterol levels and heart disease risk. We examined the LDL cholesterol-lowering response to such a diet (26% fat, 8% saturated fat, and 201 mg/day of cholesterol) as compared to an average American diet (39% fat, 15% saturated fat, and 435 mg/day of cholesterol) in 128 subjects using diet periods of 4-24 weeks for each diet phase. The mean LDL cholesterol reduction was 15% in males (n = 83) and 8% in post-menopausal females (n = 45). The effect of apolipoprotein (apo) E phenotype on responsiveness was examined. LDL cholesterol lowering in males was 14% for 60 apoE3/3 subjects, 23% for 10 apoE3/4 subjects, and 16% for 13 apoE3/2 subjects. Male apoE3/4 subjects had a significantly greater LDL cholesterol reduction (P = 0.006) and a greater decrease in the LDL/HDL ratio (P = 0.047) than apoE3/3 subjects. In females, 7% lowering in LDL cholesterol was observed in 34 apoE3/3 subjects and 11% lowering was observed in 7 apoE3/4 subjects (P = 0.12). A meta-analysis of data from published studies supports this conclusion. These data indicate that apoE phenotype modulates the LDL cholesterol-lowering response to a diet meeting NCEP Step 1 criteria, and that male subjects carrying the apoE4 allele are more responsive than other subjects.

Adult↗
PubMed1993

SPROUT: a program for structure generation.

SPROUT is a new computer program for constrained structure generation that is designed to generate molecules for a range of applications in molecular recognition. It uses artificial intelligence techniques to moderate the combinatorial explosion that is inherent in structure generation. The program is presented here for the design of enzyme inhibitors. Structure generation is divided into two phases: (i) primary structure generation to produce molecular graphs to fit the steric constraints; and (ii) secondary structure generation which is the process of introducing appropriate functionality to the graphs to produce molecules that satisfy the secondary constraints, e.g., electrostatics and hydrophobicity. Primary structure generation has been tested on two enzyme receptor sites; the p-amidino-phenyl-pyruvate binding site of trypsin and the acetyl pepstatin binding site of HIV-1 protease. The program successfully generates structures that resemble known substrates and, more importantly, the predictive power of the program has been demonstrated by its ability to suggest novel structures.

Artificial Intelligence↗
PubMed1993

Immunohistochemical study of intracranial cysts.

We present the immunohistochemical study of 11 cases of intracranial cysts: two extraventricular ependymal cysts, three colloid cysts of the third ventricle, four extraventricular choroidal cysts and two Rathke's cleft cysts. Antibodies against glial fibrillary acidic protein (GFAP), cytokeratins (AE1, CK5D, AE3), S-100 protein, epithelial membrane antigen (EMA), vimentin, neuron specific enolase (NSE), neurofilaments protein (NF) and prealbumin, were used. The epithelium of choroidal cysts, showed strong immunoreactivity for Prealbumin and cytokeratins, similar to the normal choroid plexus epithelium. The ependymal cysts showed epithelial immunoreactivity for GFAP and S-100, both glial markers expressed by the normal ependymal epithelium. On the contrary, the epithelial wall of colloid cysts and Rathke's cleft cyst, expressed epithelial markers (cytokeratins and EMA) but no neuroepithelial markers, with a immuno-phenotype similar to that of other cysts of endodermal nature. This finding supports the neuroepithelial origin for choroid and ependymal cysts, and an endodermal nature for colloid and Rathke's cleft cysts. We conclude that these immunohistochemical markers are useful in the differential diagnosis of intracranial cysts.

Brain Diseases↗
PubMed1993

[Effects of n-3 polyunsaturated fatty acids on the cardiovascular system. Should their use be recommended?].

The effects of n-3 polyunsaturated fatty acid (n-3 PFA) intake on lipoprotein metabolism, eicosanoid metabolism, coagulation and the fibrinolytic system, mediators of inflammation, and blood pressure are discussed. The possible role such effects may have on the process of atherogenesis is examined. Laboratory animal studies with n-3 PFA supplements are reviewed. Finally, a review of clinical and epidemiological studies in human subjects is made in order to evaluate whether the experimental findings have clinical relevance. The conclusion is that, at the present time, there is insufficient support for the use of n-3 PFA supplements either in prophylaxis or in treating ischemic cardiopathy.

Animals↗
PubMed1992

Effects of long-term monounsaturated- vs polyunsaturated-enriched diets on lipoproteins in healthy men and women.

The effect of dietary-fat saturation on plasma lipoprotein concentrations was assessed in 46 men and 32 women placed on a diet enriched in polyunsaturated fatty acids (sunflower oil) for 12 wk and, under isocaloric conditions, on a diet enriched in monounsaturated fatty acids (olive oil) for the next 16 wk in men and 28 wk in women. Fat comprised 37% of the total energy intake in men and 36% in women. At the end of the monounsaturated fatty acid diet no change occurred in total cholesterol (TC) in men but it increased by 9% in women. High-density-lipoprotein (HDL) cholesterol increased by 17% in men and by 30% in women. The atherogenic index (TC:HDL cholesterol) fell significantly in both sexes. No significant changes occurred in plasma low-density-lipoprotein cholesterol or in total triglycerides values. These data show that when compared with polyunsaturates, monounsaturates increased HDL cholesterol and reduced the atherogenic risk profile in both sexes.

Adolescent↗
PubMed1992

Effect of dietary monounsaturated fatty acids on plasma lipoproteins and apolipoproteins in women.

To determine the effects of dietary fat saturation on plasma lipoproteins, we studied 21 free-living normolipidemic women (13 pre- and 8 postmenopausal) on three consecutive diet periods. During the first 4 wk they consumed a saturated diet rich in palm oil and butter [19% saturated fatty acids (S), 14% monounsaturated fatty acids (M), and 3.5% polyunsaturated fatty acids (P)], followed by 6 wk of a monounsaturated diet rich in olive oil (11% S, 22% M, and 3.6% P), and 6 wk of a polyunsaturated diet rich in sunflower oil (10.7% S, 12.5% M, and 12.8% P). Compared with the diet rich in saturated fatty acids, both diets rich in unsaturated fatty acids had similar lowering effects on total and low-density-lipoprotein cholesterol. High-density lipoprotein cholesterol and apolipoprotein A-I were higher in the monounsaturated-rich period than in the polyunsaturated-rich (10.5% and 12.7% respectively, P less than 0.001) and the saturated-rich period (5.3%, and 7.9%, respectively, P less than 0.05). These effects were independent of menopause status. Our data show that at this level of fat intake (36% as calories), a monounsaturated-rich diet results in a less atherogenic lipid profile than either polyunsaturated- or saturated-rich diets.

Adult↗
PubMed1992

Fel d I allergen: skin and or saliva?

To determine the relative importance of saliva and sebaceous glands as sources of Fel d I allergen, we compared Fel d I levels at the base and tip of the hair in areas presenting more or less sebaceous glands and areas licked more or less frequently. The amount of Fel d I was significantly higher at the base than the tip of the hair. Further, it was strongly correlated with the density of sebaceous glands. This study demonstrated that the most abundant source of Fel d I allergen is cat skin.

Allergens↗
PubMed1991

Fel d I allergen distribution in cat fur and skin.

Immunohistochemical procedures were performed to ascertain Fel d I antigen (Ag) distribution in cat fur and skin biopsy specimens and to analyze Fel d I allergen concentrations in fur. One hundred strands of fur and 24 skin biopsy specimens (6 by 4 by 3 mm) from shaved areas were collected from 11 different cats. Freshly depilated hairs were immunostained by free-floating monoclonal anti-Fel d I, avidin-biotin-peroxidase complex, and either processed for scanning electron microscopic examination or mounted on glass slides for computer-assisted densitometric analysis (SAMBA system). Skin biopsy specimens were promptly frozen and sectioned just before the immunohistochemical processing. Densitometric analysis of fur demonstrated that immunoprecipitate concentrations were tenfold higher at the root than at the tip. However, this finding may be explained by decrease of the thickness of the hair cortex that varied in similar proportions. The Ag accumulated on the strand surface but may focally penetrate into the medulla through the scale-like cortical interstices. In skin biopsy specimens, Fel d I Ag was found in epithelial squamous cells, within the epidermis and hair follicles, on the surface of the epidermis and hair follicles, and in sebaceous gland cells. These data suggest that Fel d I Ag is produced by sebaceous cells and, to a lesser extent, by basal squamous epithelial cells and that it is stored mainly on the surface of the epidermis and fur.

Allergens↗