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Biomedical subjects

I Fernandez

Publications and source records attributed to I Fernandez.

At least 55 records · Page 3Linked to original sources
PubMed1992

A delayed-type hypersensitivity-inducing T-cell epitope of Semliki Forest virus mediates effective T-helper activity for antibody production.

The rational development of peptide vaccines requires the identification of both B- and T-cell epitopes. In this study, potential T-helper cell epitopes of Semliki Forest virus (SFV) were identified on the basis of their ability to induce delayed-type hypersensitivity (DTH) in mice using recombinant SFV fragments produced as hybrid proteins with beta-galactosidase in Escherichia coli and synthetic peptides coupled to beta-galactosidase. Although the tested fragments spanned almost the entire amino acid sequence of the structural proteins of SFV, only one DTH-inducing region (located between amino acid 137 and 151 of the SFV E2 membrane protein) was identified. Peptides containing this E2 region stimulated lymph node cells from SFV-primed mice in vitro. The ability of the identified T-cell epitope to induce a specific T-helper response in mice was evaluated using synthetic peptides that contained combinations of the DTH-inducing region and different previously identified linear B-cell epitopes of E2. These peptides proved able to induce an antipeptide IgG response in mice in an H-2d-restricted fashion. One of the peptides was also able to induce high titres of IgG reactive with SFV-infected cells and protected 70-100% of the peptide-immunized mice after challenge with virulent SFV. Our findings suggest that DTH and T-helper activity are mediated by different doses of the same T-cell epitope.

Animals↗
PubMed1991

A method for culturing rat oviduct gamma-aminobutyric acid cells.

A technique for the culture of rat oviduct gamma-aminobutyric acid (GABA) cells is described. The technique involves first explaining the fimbria and preampulla, which are the oviduct divisions with the highest density of GABA cells. The explanted tissue is cultured in a serum-free medium, to propagate the outgrowing cells. Under the experimental conditions we describe, the majority of the cells maintain GABA expression, as determined by immunostaining with a GABA antiserum.

Animals↗
PubMed1991

Higher lifetime prevalence of respiratory diseases in panic disorder?

Current and past frequencies of respiratory diseases were assessed in 30 patients with panic disorder, 30 patients with obsessive-compulsive disorder, and 30 patients with eating disorders. Lifetime prevalence of respiratory disorders was significantly higher in patients with panic disorder (47%) than in patients with either obsessive-compulsive disorder (13%) or eating disorder (13%). Point prevalences showed no differences.

Adult↗
PubMed1991

[Contribution to the pharmacodynamic study of a ketosulphoxide derivative (omega-methylsulphinyl alpha-acetothiophene). Activity on the CNS].

In order to establish the pharmacological profile of a series of ketosulphoxide derivatives which have been synthesized in the pharmaceutic and organic chemistry department of the Sevilla Pharmacy Faculty, a study of omega-methylsulphinyl alpha-acetothiophene has been initiated. Experiments were carried out on male Swiss mice, using a dosage of 100 and 200 mg/kg. High toxicity tests have been undertaken, followed by an investigation of activity at CNS levels. The results obtained show that the composite mentioned has a marked depressant activity lacking in any significant toxic effects.

Animals↗
PubMed1989

Orbital hydatid cyst of Echinococcus oligarthrus in a human in Venezuela.

This study reports the first known case of human hydatid disease caused by the larval stage of Echinococcus oligarthrus. The patient, a native Venezuelan female, presented a single cyst localized intraorbitally behind the left eye (retroocular), which was discovered by computed tomography. The cyst was removed by surgery, and after parasitological studies it was identified as an E. oligarthrus hydatid cyst. This is also the first case of intraorbital hydatid cyst in humans in Venezuela.

Animals↗
PubMed1988

Ultrastructure of the oocyst wall formation in Eimeria? beauchampi Leger and Duboscq, 1917, a coccidian parasite of Glossobalanus minutus (Kow.) (Enteropneusta, Hemichordata).

The ultrastructure of the developing oocyst of Eimeria? beauchampi Leger and Duboscq, 1917 was studied from the ventral digestive epithelium of the hepatic region of Glossobalanus minutus (Enteropneusta). A possible building mechanism of the oocyst wall is deduced and discussed from the present data and the available literature. During oocyst wall formation a total of 5 membranes were observed at or near the surface of the parasite among which some wall-forming materials will be stored. The origin and fate of such wall-forming materials are discussed and compared with data from other coccidians. The apparently full-formed wall is made up of an outer, dense layer, a median layer showing a labyrinthic-tubular lattice substructure, and an inner, homogeneous and osmiophilic layer. A micropyle measuring 0.35 micron in diameter is also described.

Animals↗
PubMed1987

Study of different factor VII deficiency variants in nine families from Spain.

Twenty-three patients with congenital factor VII (FVII) deficiency, belonging to 9 kindreds were studied. Immunological variants were classified according to the relationship between FVII coagulant activity (FVIIC) and the level of FVII antigen (FVIIAg), considering 3 previously described groups: VII-, VII+ and VIIR. Activation variants were determined by the reactivity pattern with three different thromboplastins. One patient was classified as VII-, 16 as VII+, and 6 as VIIR. Three patients belonging to the same kindred showed a Padua 2 FVII deficiency, and 1 patient showed a Padua 1 variant. There was no correlation between antigenic or activation variants and severity of bleeding tendency. Classical autosomal recessive mode of inheritance was observed in VII- and VII+ families. Nevertheless, a possible autosomal dominant trait was observed in VII+ kindreds.

Adult↗
PubMed1986

Induction of polypeptides in Saccharomyces cerevisiae after ultraviolet irradiation.

Alterations in the synthesis of proteins following exposure of Saccharomyces cerevisiae to UV light were investigated using radioactive labelling and two dimensional electrophoresis. UV-irradiation induced the synthesis of various proteins. Among them the analogue of the RecA protein of Escherichia coli (Angulo et al. 1985) and two other polypeptides (34 Kd and 35 Kd, pI 5.8) were observed in all four strains analyzed namely two DNA-repair deficient (rad-) strains: (rad6-1 and pso2-1) and their isogenic wild type RAD+ strains.

Electrophoresis, Polyacrylamide Gel↗
PubMed1985

The alpha-adrenergic receptor: radiohistochemical analysis of functional characteristics and biochemical differences.

The partial agonist [3H]para-aminoclonidine was used to label alpha 2-adrenergic binding sites in intact sections of the rat central nervous system using in vitro labeling receptor autoradiographic techniques. The distribution of alpha 2-agonist binding sites closely parallels the reported distribution of noradrenergic and adrenergic cell groups and their terminal fields, particularly the projections of the medullary catecholamine neurons. This distribution of alpha 2 binding sites confirms physiological studies which indicate that the anti-hypertensive actions of alpha 2-agonist compounds are mediated centrally in medullary and spinal centers involved in the control of parasympathetic and sympathetic outflow. Further, the high concentrations of alpha 2 binding sites in pontine and limbic areas such as the locus coeruleus, parabrachial nucleus, dorsal raphe, hypothalamus, amygdala, bed nucleus of the stria terminalis, septum and entorhinal cortex offer an anatomical basis for understanding the anxiolytic and antidepressant actions of drugs like clonidine. The antagonists [3H]prazosin and [3H]WB4101 were used to study the distribution of alpha 1-adrenergic binding sites in the rat forebrain and biochemical studies were performed to analyze the marked differences that were initially seen in the distribution of [3H]prazosin and [3H]WB4101 binding sites. Several pieces of evidence derived from both biochemical and autoradiographic studies suggest that [3H]prazosin and [3H]WB4101 act at distinctly different binding sites. However, both sites may represent components of an alpha 1-adrenergic receptor-effector complex since a high degree of overlap was seen in the binding site distribution of these two ligands and since kinetic interactions could be demonstrated in at least one region of the brain, the hippocampus. Differences noted in the relative displacements of [3H]prazosin and [3H]WB4101 binding in various forebrain regions could reflect differences in the coupling efficiency of the [3H]prazosin and [3H]WB4101 component of the hypothesized complex. Further, in some regions, [3H]WB4101 labeled a binding site that is different from the alpha 1-receptor. Thus, [3H]prazosin and [3H]WB4101 binding sites seen in forebrain regions such as lamina V of the cortex, thalamic nuclei and dorsal raphe probably represent alpha 1-adrenergic receptors and confirm electrophysiological and biochemical studies which demonstrate that adrenergic transmission in these regions can be mediated through an alpha 1-receptor.

Affect↗
PubMed1984

[3H]prazosin binding to central nervous system regions of male and female rats.

Membranes were obtained from the pituitary gland and 13 cerebral regions of male rats and of females during two endocrinological states (estrous and diestrous-1), and assayed for alpha 1-receptor binding, using [3H]prazosin. At two [3H]prazosin concentrations, one near its binding dissociation constant and the other at a value at which the plateau was reached in the binding saturation curve (0.2 and 1.2 nM respectively), [3H]prazosin binding was highest to the frontal cortex, lowest to the spinal cord, and showed no differences in any region under any of the hormonal states tested. Results are discussed in relation to previously reported hormonal effects on alpha 1-receptors.

Animals↗
PubMedDate not supplied

Omega3 polyunsaturated fatty acids and maize flour diets.

OBJECTIVES: Nutrition disorders caused by a 6.5% maize protein diet (M), unbalanced in its indispensable amino acid pattern, provokes an arrest on cellular proliferation and maturation in the thymus of growing rats. We investigated the effect of diet supplementation with different amounts of omega3 polyunsaturated fatty acid (M = 0 mg/d, M1 = 12 mg/d, M2 = 24 mg/d, respectively) on thymus, plasma lipid concentrations, and hepatic tissue. METHODS: A well-nourished age-matched control group received stock diet from weaning. The animals (8 to 10 per group) received the diets for 9 d. At the end of the experimental period, they were killed, thymuses were removed, and cell number, absolute number of T cells labeled by the monoclonal antibody W3/13, plasma lipid profile (total cholesterol, triacylglycerols, high- and low-density lipoprotein cholesterols), and oxidative stress in hepatic tissue were determined. RESULTS: Only M2 reached the values of the control group when cell number and absolute number of T cells were compared. No statistical differences were observed among the M, M1, M2, and control group when high- and low-density lipoprotein cholesterols and hepatic lipid peroxidation were considered. CONCLUSIONS: The supplementation of a 6.5% maize protein diet with 24 mg/d of omega3 polyunsaturated fatty acid can recover the proliferation and absolute number of T cells labeled with W3/13 without affecting lipid profile and hepatic lipid peroxidation.

Animals↗