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F Vadillo-Ortega

Publications and source records attributed to F Vadillo-Ortega.

29 records · Page 2Linked to original sources
PubMed1993

Identification and partial characterization of an immunoglobulin A protease associated with human sperm.

The ability of human sperm to evade local humoral immune response at the female genital tract has received little attention. As some microorganisms inactivate secretory immunoglobulin A (S-IgA) by enzymatic degradation as a part of their pathogenic mechanism, we decided to test the hypothesis that there is an IgA protease in human semen that helps sperm to progress through the cervix uteri. Incubation of different semen fractions in the presence of S-IgA revealed IgA protease activity associated with raw semen or sperm but not with seminal plasma; raw semen and sperm produced two split products of 66 kDa and 45 kDa, respectively, in SDS-PAGE. The enzymatic activity was blocked with EDTA. IgG and IgM were not digested under the same experimental conditions. Degradation of S-IgA by an IgA protease on the sperm surface may be among the mechanisms present in semen that enable sperm to evade an immune response in the female genital tract.

Female↗
PubMed1992

Novel model for study of human sperm chemotaxis.

OBJECTIVE: To develop and test an adequate method for the study of sperm chemotaxis. DESIGN: A model based on a double-chamber design and a matrix of 0.5% hyaluronic acid was used to test the response of human sperm to chemotactic signals from follicular fluid (FF). RESULTS: A plateau of migration was reached at 10 minutes of incubation; under this condition, 70% of sperm migrated toward chambers with FF, less than 20% to the opposite side, and the rest remained at the site of application. Intra-assay and interassay coefficients of variation using pools of FFs were 17.2% and 23%, respectively. CONCLUSION: These data confirm previous findings and support the use of this novel model for the study of chemotaxis on human gametes.

Chemotaxis↗
PubMed1991

Human amniotic fluid modulation of collagenase production in cultured fibroblasts. A model of fetal membrane rupture.

The participation of a mechanical factor as the only cause of rupture of fetal membranes during normal labor or premature rupture has been criticized, and the involvement of an enzymatic mechanism has been proposed. In this study we analyzed the effect of human amniotic fluids at different gestational ages on the collagenase synthesis of cultured fibroblasts. Our results show that term amniotic fluids are capable of inducing the synthesis of collagenase and other proteases in fibroblasts, as revealed by selective increases in collagenase activity and in immunoreactive collagenase. Nonterm amniotic fluids failed to do the same. This phenomenon is proposed as a model for studying the collagen degradation of fetal membranes during term gestation.

Amniotic Fluid↗
PubMed1990

Evidence that human follicular fluid contains a chemoattractant for spermatozoa.

Considering that information from the literature clearly establishes that human follicular fluid enhances both motility and viability of spermatozoa and that this fluid contains substances with chemotactic activity for leukocytes, we looked to see if follicular fluid might exert any chemical attraction to male germinal cells. In an vitro model using 0.8% agarose plates, it was demonstrated that the number of cells migrating to wells containing follicular fluids from patients in a program for GIFT, classified as mature in accordance to oocyte morphology, was significantly higher than those migrating to control wells. Further studies are needed to confirm these results and to study the possible specificity of the signal.

Body Fluids↗
PubMed1990

Collagen metabolism in premature rupture of amniotic membranes.

Collagen content, acid-soluble collagen, degradation activity, and collagen biosynthesis were measured in 22 normal and 20 prematurely ruptured membranes from pregnancies near term (37 weeks or more). Although no significant differences were found in the collagen content, a clear correlation was found between this value and the interval from premature rupture to delivery. Collagenolytic activity and collagen solubility were higher and collagen synthesis was lower in amniotic membranes that ruptured prematurely. These studies suggest that premature rupture of membranes is associated with extensive changes in collagen metabolism.

Adult↗
PubMed1989

A latent collagenase in human aqueous humor.

It has been suggested that the trabecular meshwork may be involved in the pathogenesis of open-angle glaucoma, and some authors have pointed out that disorders of the extracellular matrix components may play a role; nevertheless, nothing is known about the normal metabolism of connective tissue molecules in this particular tissue. We recently initiated some studies in this field and have focused on the in vitro effects of aqueous humor on collagen metabolism. We report the finding of a latent collagenase of low molecular weight in aqueous humor obtained from cataractous patients; the enzyme was identified through several methods, including its in vitro activity against radiolabelled type I collagen and additionally with a zymogram technique. It was partially characterized by high-performance liquid chromatography.

Aqueous Humor↗
PubMed1988

Experimental diffuse interstitial renal fibrosis. A biochemical approach.

In this paper we describe two simple experimental models of diffuse interstitial renal fibrosis in the rat. One develops 25 days after unilateral renal vein ligation, and the other 15 days after unilateral ureteral double ligation and section. In both models fibrosis is examined morphologically and biochemically, the latter with emphasis on collagen turnover. In addition to a description of the histology, also presented are quantitative biochemical data on four features of tissue collagen turnover, namely total content, concentration, biosynthesis, and degradation. Although the microscopic picture of both models can be adequately described as interstitial diffuse renal fibrosis, their mechanisms are different: unilateral renal vein ligation is an example of collapse fibrosis, whereas unilateral ureteral double ligation and section is a model of absolute fibrosis. In both models however, decreased collagen degradation is the significant metabolic abnormality.

Animals↗
PubMedDate not supplied

Evidence of endothelial cytotoxic compounds in placental extracts from preeclamptic women.

OBJECTIVE: To determine whether placenta and plasma of preeclamptic women contain factors that cause endothelial cell damage. METHODS: Placental extracts and plasma from preeclamptic and normotensive women were added to cultures of normal human umbilical vein endothelial cells and their effect on their viability, was determined by MTT reduction and 51chromium release. RESULTS: Placental extracts from normotensive and preeclamptic women were cytotoxic to endothelial cells, but not the plasma from both groups. Mean +/- standard deviation values of cytotoxicity index in preeclamptic and normotensive placental extracts using the MTT reduction were 70.3 +/- 6.76% and 51.4 +/- 8.81%, respectively, showing a significant difference (P < .0001). Using the 51chromium-release assay, preeclamptic placental extracts showed cytotoxic effects of 87.6 +/- 13.47% compared with 17 +/- 20.60% in control patients. The cytotoxic activity decreased after trypsin digestion and heat treatment in both groups. CONCLUSIONS: A cytotoxic factor to endothelial cells in placental extracts of preeclamptic women was identified. This compound is thermolabile and sensitive to trypsin digestion.

Cells, Cultured↗