Biomedical subjects

C Revilla

Publications and source records attributed to C Revilla.

At least 19 recordsLinked to original sources

PubMed2006

Phenotypic and functional characterization of porcine granulocyte developmental stages using two new markers.

Here, we describe two new surface antigens, named 6D10 and 2B2, whose expression is restricted to porcine granulocytes. 6D10 is only detected in neutrophils and its expression decreases from promyelocytes to mature cells. By contrast, 2B2 antigen is selectively expressed in mature neutrophils, eosinophils and basophils. The expression of these antigens along granulocyte maturation allows the discrimination of several developmental stages of granulocytes based on phenotypic, morphological and functional characteristics previously established. Moreover, these new markers are useful tools to easily characterize the different granulocytes lineages (neutrophils, eosinophils and basophils). By using multiparameter flow cytometric analysis, we have performed a phenotypic and functional characterization of the granulocyte subsets identified by the combination of 6D10 and 2B2 antigens.

Animals↗

PubMed2005

Differential expression of chemokine receptors and CD95 in porcine CD4(+) T cell subsets.

Among other differences, naïve and memory T cells show distinct migratory patterns and susceptibility to CD95-mediated cell death. We have recently characterised in the pig two subsets of CD4(+) T cells, based on the expression of the 2E3 marker, that display phenotypic and functional features of naïve (CD4(+)2E3(+)) and effector/memory (CD4(+)2E3(-)) T cells. In this study, we have analysed the expression of several chemokine receptors, as well as the distribution of CD95 antigen (APO-1/Fas) in these CD4(+) T cell subsets. CD4(+)2E3(-) T cells express high levels of CXCR3 and CCR4 transcripts but not of CCR7. On the contrary, CCR7 is clearly detected in CD4(+)2E3(+) T cells, whereas CXCR3 and CCR4 are negative or present at trace levels. These subsets also differ in the expression of CD95 antigen, being CD95 positive cells significantly more abundant in the CD4(+)2E3(-) cell subset. These findings, although based on a small number of animals, fit well with those reported for naïve and memory CD4(+) T cells in humans.

Animals↗

PubMed2004

Analysis of functional heterogeneity of porcine memory CD4+ T cells.

Previous studies have identified swine helper memory T cells as CD4+CD8alpha+SLADR+. We have recently described a new porcine surface antigen (2E3) selectively expressed on CD4+ T cells that allows to divide these cells into naive (2E3+) and effector/memory (2E3-). However, although the majority of CD4+2E3- cells are CD8alpha+SLADR+, a minor proportion do not express SLADR and/or CD8alpha. Here, we have analyzed the functional capacity of these CD4+2E3- subsets to proliferate to a recall antigen. Both SLADR- and CD8alpha- cells proliferated in response to lysozyme, but at lower levels compared to the whole population CD4+2E3-. Besides, after activation with PMA plus ionomycin, CD4+2E3-SLADR- T cells produced IFNgamma and TNFalpha, although they did also in lower proportion than the whole CD4+2E3- population. Most of the IFNgamma-TNFalpha+, IFNgamma+TNFalpha+, IFNgamma+TNFalpha- cells were CD8alpha+ and CD45RA-, while IFNgamma-TNFalpha- cells showed a less differentiate phenotype.

Animals↗

PubMed2004

2E3, a new marker that selectively identifies porcine CD4+ naive T cells.

We describe a novel antigen recognized by mAb 2E3 selectively expressed in the periphery by a subset of porcine CD4+ T cells. Both, CD4+CD8alpha- and CD4+CD8alphalow T cell subpopulations express this antigen. CD4+2E3+ T cells show phenotypical and functional characteristics of nai;ve cells. The majority of them are CD29low, CD45RAhigh, CD49dlow, CD11alow, CD18low, and SLA-II-. After mitogen activation CD4+2E3+ T cells express high levels of IL-2 mRNA, but only traces of IFN-gamma or IL-4 mRNA. Indeed a minor percentage of cells stained positive for IFN-gamma when assessed by flow cytometry. Moreover, CD4+2E3+ T cells did not proliferate in response to the recall antigen lysozyme, although they did efficiently to the mitogen ConA. By contrast, CD4+2E3- T cells show phenotypical and functional characteristics of primed cells. They express markers associated to a memory phenotype, respond to the recall antigen lysozyme, and produce high amounts of IFN-gamma and IL-4.

Animals↗

PubMed2003

Social integration of juvenile amputees: comparison with a general population.

The objective was to assess the social integration of juvenile amputees according to marital status, schooling and occupation, and to compare it with the population of Asturias, Spain. A retrospective study was carried out of the juvenile amputees registered from 1976 to 1999 at the Prosthetics Unit of the Asturias Central Hospital (n=281 amputees). The proportion of single women amongst the amputees was greater than in the population of Asturias (p<0.05). Amongst the male amputees, relative to the general population, there was a larger proportion of the group with primary studies (p<0.001) and a smaller proportion with secondary studies (p<0.001). At the higher level (university) there were no differences, either in men or in women. As regards occupation, amongst the amputees a larger number was found who were retired or unemployed (p<0.05 and p<0.001). In conclusion, juvenile amputees do not show differences compared to the general population with regard to their attendance at a higher or university level of education. However, if their social integration is considered through occupation, male amputees show a greater proportion of unemployment, which is a clear reflection of their handicap.

Adolescent↗

PubMed2002

Phenotypic characterization of porcine IFN-gamma-producing lymphocytes by flow cytometry.

We have developed a three-colour flow cytometric assay for phenotypic characterization of porcine IFN-gamma-producing lymphocytes. Analyses of activated swine peripheral blood mononuclear cells (PBMC) showed a significant difference in the proportion of IFN-gamma producing cells between young and adult animals (13.2+/-5.8% versus 34.2+/-5.7%). The majority of IFN-gamma producing cells were alphabeta T lymphocytes, although there was also an important proportion of gammadelta T cells particularly in young animals. Within the alphabeta T lymphocytes, the double positive CD4(+)CD8(lo) subset, that contains memory T cells, produced high levels of IFN-gamma, whereas the CD8(hi) T cells ranged from low to high levels of IFN-gamma. Also, consistent with a higher production by memory T cells, the CD45RA(-) subset of both CD4(+) and CD8(+) cells contained higher numbers of IFN-gamma producing cells than the CD45RA(+) subset. Finally, no production of IFN-gamma by either B cells (CD21(+)) or monocytes (SWC3(+)) was detected. This assay may be useful for the assessment of cell-mediated immunity in vaccine trials and may contribute to our understanding of the role of IFN-gamma in protective immunity against important viral diseases of the pig.

Animals↗

PubMed2000

Phenotypic characterization of monocyte subpopulations in the pig.

We have recently described the existence of two subsets of porcine monocytes based on the expression of CD163. In this study we compare the expression of a number of cell surface antigens in CD163+ and CD163- monocyte subsets using three-color flow cytometry. These monocyte subsets show differences with respect to the expression of MHC class II antigens (SLA-DR and DQ) and a variety of adhesion molecules (CD11a, wCD11c, wCD29, CD49d) that are expressed at higher levels on CD163+ monocytes, and of CD14 that is higher expressed by CD 163- cells. These differences on phenotype could reflect differences in the ability of these two subsets to migrate to tissues and may account for the higher allostimulatory capacity of CD163+ cells. In some aspects, the phenotype of CD163+ monocytes resembles that of mature macrophages. In vitro serum-induced maturation of monocytes into macrophages lead to the expression of SWC9 together with an increase in the expression of CD163 and a reduction in that of CD14. These results delineate a maturation pathway where CD14hiCD163-SWC9- monocytes develop into CD14loCD163+SWC9- monocytes and these cells into CD14loCD163+SWC9+ macrophages.

Animals↗

PubMed1998

[Neurophysiological study in Alpers syndrome].

INTRODUCTION: Infantil progressive polydystrophy was described by Alpers in a child with psychomotor retardation, crises which were resistant to treatment and diffuse loss of cortical neurons. OBJECTIVE: The aim of this study was to review the neurophysiological aspects of Alpers syndrome and their clinical correlation. MATERIAL AND METHODS: We present three children with subacute encephalopathy, progressive psychomotor retardation, myoclonic epilepsy which was resistant to treatment and crises of apnea, who had degeneration of the cerebral grey matter. Serial EEG, polysomnographs, auditory evoked potentials of the brain stem and visual evoked potentials were done. RESULTS: The electroencephalogram findings showed the presence of complex bursts of acute waves, small many-pointed or slow waves of great amplitude which were irregular and arrhythmical, lasting one to five seconds, separated by periods of inactivity on the tracing which lasted from three to ten seconds. The EEG was distinctive, changing over the course of the illness, and with increasing numbers and duration of the bursts of suppression of cerebral bioelectric activity. Polysomnography showed cerebral bioelectric activity which was markedly unstructured and with little difference between the tracings when asleep and when awake, together with a large number of apneas of obstructive and mixed types. The PEAT showed reduced amplitude and altered morphology in all the waves, and even absence of some of them. The visual evoked potentials were asymmetrical and with delay in the latency of the P100 wave. CONCLUSIONS: Although definite diagnosis of progressive neurone degeneration requires post mortem examination of the brain, clinico-pathological studies, including electrophysiological, radiological and biochemical studies are sufficiently characteristic to suggest the diagnosis during life.

Child, Preschool↗

PubMed1997

Treatment with anti-LFA-1 alpha monoclonal antibody selectively interferes with the maturation of CD4- 8+ thymocytes.

Maturation of T lymphocytes in the thymus is driven by signals provided by soluble factors and by the direct interaction between thymocytes and stromal cells. Although the interaction between T-cell receptor (TCR) and major histocompalibility complex (MHC) molecules on stromal cells is crucial for T-cell development, other accessory molecules seem to play a role in this process. In order to better understand the role of lymphocyte function-associated antigen-1 (LFA-1) and intercellular adhesion molecule-1 (ICAM-1) molecules in thymocyte maturation, mice were treated from birth with saturating doses of non-cytolytic-specific monoclonal antibodies. The effect of this treatment on thymocyte subpopulations and the expression of CD3 and TCR-alpha beta by these cells was investigated by flow cytometry. Our data demonstrated that the effective saturation of LFA-1 alpha chain in the thymus, but not ICAM-I or LFA-I beta chain, selectively interfered with the maturation of CD8+ T cells, as manifested by a marked reduction in the frequency of CD4-8+ thymocytes expressing high levels of CD3 and TCR-alpha beta. This selective reduction was also observed in peripheral blood mononuclear cells and spleen cells. The analysis of the frequencies of various V beta TCR showed that CD4-8+ thymocytes were globally affected by the treatment. These results underline the importance of the interaction between LFA-1 and its ligands in the maturation of CD8+ T cells and document the existence of different molecular requirements for the differentiation of CD4+ and CD8+ T cells.

Animals↗

PubMed1997

[Neurophysiological aspects of Proteus syndrome].

INTRODUCTION: The Proteus Syndrome was defined in 1983 by Wiedeman. However, the first case mentioned in the literature was that of Joseph Merrick, the Elephant Man, presented by Sir Frederick Treves in 1884. It is a rare pathological condition. Its multiple clinical features include; partial gigantism of hands and/or feet, pigmented nevi, hemihypertrophy of the body, tumors, skeletal anomalies, growth disorders and visceral anomalies. Hereditary transmission has not been clearly defined. Diagnosis and treatment require the participation of experts from several medical and surgical specialties. CLINICAL CASE: We present a case sent to our hospital for the surgical correction of cranio-facial malformations. Epileptic crises post-operatively indicated the need for neurological and neuro-physiological study. This was done by means of conventional electro-encephalography: brainstem, somato-sensorial and visual auditory evoked potentials, together with imaging techniques which showed the structural and functional asymmetry of the central nervous system at both cerebral and brainstem levels. CONCLUSIONS: Few neuro-physiological studies are included in the literature we reviewed for this paper. Therefore we do not know whether the functional anomalies of the central nervous system which we describe should be considered to be part of the syndrome.

Adult↗

PubMed1996

Expression of tyrosine kinase gene in mouse thymic stromal cells.

Amongst the most important signal transduction molecules involved in regulating growth and differentiation are the protein tyrosine kinases (PTK). Since T cell development is a consequence of interactions between thymic stromal cells (TSC) and thymocytes, identification of the PTK in both compartments is required to dissect the mechanisms that control this process. Here we report a search for PTK in mouse TSC, using RT-PCR to survey the repertoire of PTK mRNAs expressed in a freshly isolated TSC preparation. We identified 10 different PTK cDNAs among the 216 cDNAs sequenced, and demonstrate that transcripts of three of those (ufo, fyn and fer) are widely expressed among a large panel of immortalized thymic epithelial cell lines (TEC) and in primary cultures of TSC. Of the other seven, none were expressed in established TEC lines but, instead, displayed distinct expression patterns in cell types likely to have contaminated the fresh TSC preparation, i.e., macrophages, B cells, T cells and fibroblasts. Among the three PTK expressed in TEC lines, only one, ufo, exhibited expression exclusively in cells of non-hemopoietic origin. Although expression of ufo (also known as tyro 7, axl or ark) is not thymic-specific, in that it is also expressed in cell types of mesodermal origin in other tissues, its presence in TEC suggests a role for ufo in differentiation of the TSC compartment. Consistent with this notion, high-level expression of this receptor PTK at the protein level could be documented in every TEC line investigated, as well as in fresh thymus tissue sections. These data provide the first example of a receptor PTK in TSC and open new approaches to study the regulation of TSC differentiation.

Amino Acid Sequence↗

PubMed1996

Insulin resistance in offspring of hypertensive subjects.

OBJECTIVE: To assess whether apparently healthy subjects with a family history of systemic hypertension have a higher risk of presenting the insulin resistance syndrome. SUBJECTS: Three hundred and eighty-six subjects aged 20-65 years. SETTING: A middle socio-economic class urban community from Mexico City. METHOD: All subjects and, when necessary, their first-degree relatives, answered a questionnaire and underwent a physical examination with measurement of height, weight and blood pressure. Serum insulin, glucose, cholesterol and triglycerides were measured during fasting and 2 h after an oral load of 75 g glucose. RESULTS: A family history of systemic hypertension was present for 167 (43%) of the subjects, of whom 123 (31%) were obese. Subjects with a family history of hypertension had higher systolic blood pressures than did those without such a history (120 +/- 15 versus 115 +/- 10 mmHg). In the logistic regression model, the body mass index and age showed statistically significant effects on the fasting glucose:insulin ratio and on serum insulin levels after an oral load of glucose. When men and women were analysed separately, only in men were higher systolic and mean blood pressures and lower glucose:insulin ratios observed. In the logistic regression analysis the body mass index was a significant predictor of the glucose:insulin ratio and serum insulin levels after an oral load of glucose, especially in men. CONCLUSION: Apparently healthy male offspring of hypertensive parents have higher blood pressure levels and lower insulin sensitivities than do offspring of normotensive parents. Insulin resistance was related to obesity, but not to a family history of hypertension, as had previously been reported by other research groups.

Adult↗

PubMed1996

Nephropathy in low income diabetics: the Mexico City Diabetes Study.

Among the most serious complications associated with diabetes mellitus (DM) is nephropathy (DN). In Mexico, there is little information on the frequency and clinical characteristics of DN in the Mexican population. We present results of a population-based survey designed to estimate the prevalence of DN. The low income population consisted of 15,532 inhabitants. All 35- to 64-year-old males and non-pregnant women residing in the survey area were identified as eligible for the study (3505; 22.6%). A home interview was obtained in 2810 (80.2%). A physical exam with oral glucose tolerance test was obtained in 2282 (81.2% of those interviewed). DM was diagnosed in 304 (crude rate 13.3%). Mean age for men and women with DM was 51.6 +/- 8.4 and 52.2 +/- 7.5, respectively. Duration of DM in men was 9.2 +/- 8.1 and in women, 7.3 +/- 6.7 years. Hypertension was diagnosed in 19.8% of men and 18.1% of women. Diabetic retinopathy of any level was found in 55.4% of men and 45.7% of women. Mean glycohemoglobin in men was 9.6 +/- 2.1 and in women 9.5 +/- 2.2% (normal 4-8%). At baseline, proteinuria (1+ or more, by dipstick) was found in 24.7% of men and 9.6% of women, microalbuminuria (MA) in 84.4% of men and 63.8% of women. Quantitative albuminuria was abnormally high in 54.7% of men and 40.3% of women. In the 203 diabetics studied with 24 h urine collection for creatinine clearance, normal renal function was found in 69.1% of men and 47.5% of women, reduced renal function was found in 26% of men and 50% of women, renal insufficiency was diagnosed in 4.9% of men and 1.6% of women. One patient was on dialysis and in a subsequent follow up, we found that 2.3% of the patients had died of renal failure, six men (46-63 years) and a woman of 62 years. We conclude that DN is a very serious threat to this population. The high case fatality rate associated with this condition maintains a low prevalence. It is important to develop a program to diminish the frequency of this condition.

Adult↗

PubMed1994

Anti-LFA-1 (CD11a) monoclonal antibody interferes with neonatal induction of tolerance to alloantigens.

The injection of (C57BL/6 x BALB/c)F1 spleen cells into newborn BALB/c mice results in the induction of a specific cytotoxic T lymphocyte (CTL) tolerance to the alloantigens. On the contrary, alloreactive CD4+ T cells persist in the host and are still able to activate autoreactive F1 B cells to produce autoantibodies. This state of "split tolerance" is closely associated with the development of a lupus-like autoimmune syndrome. The LFA-1 integrin plays a relevant role in homing, intercellular adhesion and tranduction of co-stimulatory signals in leukocytes. Because of the beneficial effects of anti-LFA-1 monoclonal antibodies (mAb) treatment in various models of organ transplantation and autoimmune disease, we have investigated if such a treatment could interfere with the induction of neonatal tolerance or the development of the autoimmune syndrome in F1 cell-injected newborn mice. For this purpose, BALB/c mice neonatally injected with F1 cells were treated from day 1 up to day 15 with a non-cytotoxic anti-LFA-1 (CD11a) mAb. Anti-LFA-1 mAb treatment interfered with the persistence of a stable chimerism and with the establishment of CTL tolerance, as shown by rejection of allogeneic skin grafts and F1 B cells, and by a normal in vitro CTL activity against the corresponding alloantigens. As a consequence, these mice did not develop the characteristic autoimmune features seen in close association with an effective induction of CTL tolerance to alloantigens. These results stress the importance of the interactions between LFA-1 and its ligands during the neonatal induction of tolerance to alloantigens.

Animals↗

PubMed1994

Neuroprotective effect of acidic fibroblast growth factor on seizure-associated brain damage.

The neuroprotective effect of acidic fibroblast growth factor (aFGF) has been analysed in a rat model of seizures-associated brain damage. We report that after treatment with a convulsivant dose of Kainic acid, systemically administered aFGF prevents neuronal degeneration in specific brain areas, mainly in the hippocampal formation. Our findings extend the potential pharmacological use of fibroblast growth factors and afford new data to understand the neurophysiology of these proteins.

Animals↗

PubMed1993

Autoimmune syndrome after induction of neonatal tolerance to I-E antigens.

Neonatal injection of semiallogeneic spleen cells induces a state of specific tolerance to the parental alloantigens, but also the development of an autoimmune syndrome known as host-versus-graft disease (HVGD). The autoimmune features are a consequence of the allogeneic cooperation between persisting alloreactive host T helper type 2 (TH2) cells and donor semiallogeneic B cells. It has been established that I-A alloantigens play a central role in the triggering of this HVGD. Here it was investigated if I-E antigens, which have shown functional differences, regarding autoimmunity and alloreactivity, with respect to I-A antigens, are also able to trigger this autoimmune syndrome. The injection of spleen cells from [B10.A(4R) x B10.A(2R)]F1 (I-E+) hybrid mice into newborn B10.A(4R) (I-E-) mice was accompanied by the establishment of chimerism and also by the development of a characteristic, but moderated, HVGD. The weak intensity of this HVGD is likely due to the moderation of the alloreactive responses induced against I-E molecules. Moreover, the marked increase in the levels of IgE and in the titers of anti-DNA IgG1 antibodies strongly suggest that alloreactive TH2 cells play also a main role in the autoimmune syndrome following tolerization to I-E antigens. Therefore, it is concluded that the I-E and I-A isotypes are functionally similar with respect to the allogeneic cellular interactions that account for the HVGD.

Animals↗

PubMed1992

Complex formation between ferredoxin and ferredoxin-NADP+ reductase from Anabaena PCC 7119: cross-linking studies.

Ferredoxin-NADP+ reductase and ferredoxin from the cyanobacterium Anabaena PCC 7119 have been covalently cross-linked by incubation with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide. The covalent adduct, which shows a molecular mass consistent with a 1:1 stoichiometry of the two proteins, maintains nearly 60% of the NADPH-cytochrome c reductase activity of the enzyme saturated with ferredoxin and this value is considerably higher than when equimolar amounts of both proteins are assayed. No ternary complexes with Anabaena flavodoxin or horse heart cytochrome c were formed, suggesting that the binding site on the enzyme is the same for ferredoxin and flavodoxin and that ferredoxin-NADP+ reductase and cytochrome c bind at a common site on ferredoxin. In the noncovalent complex, titrated at pH 7, the oxidation-reduction potential of ferredoxin becomes 15 mV more negative and that of ferredoxin-NADP+ reductase 27 mV more positive compared to the proteins alone. When covalently linked, the midpoint potential of the enzyme has a value similar to that in the noncovalent complex, while the ferredoxin potential is 20 mV more positive compared to ferredoxin alone. The changes in redox potentials have been used to estimate the dissociation constants for the interaction of the different redox forms of the proteins, based on the value of 1.21 microM calculated for the oxidized noncovalent complex.

Anabaena↗

PubMedDate not supplied

[Behavior disorders during REM sleep. Two clinical cases].

INTRODUCTION: The behavior disorder occurring during REM (Rapid Eye Movement) sleep is a parasomnia characterized by absence of atonia typical of this phase of sleep, although the other characteristics are maintained, namely rapid eye movements and desynchronization of cortical electrical activity. Clinically it is accompanied by abrupt, often violent movements, which may involve a limb or the trunk in relation to dreams typical of this phase of sleep, and which may interrupt sleep. Many pathological processes have been described, including: the Shy-Dragger syndrome, Parkinson's disease, olivopontocerebellar atrophy, multisystemic atrophy, in relation to certain antidepressant drugs, and most frequently the idiopathic form. CLINICAL CASES: We present two cases, one diagnosed as olivopontocerebellar atrophy and another in which there were no pathological findings. Both were referred to our department for the study of possible sleep disorders. In both cases neurophysiological studies, basically polysomnography with monitorization of various muscle groups and video, led to the diagnosis. CONCLUSIONS: We discuss the diagnostic and physiological criteria, and physiopathological explanations of each case, with special reference to N-Methyl-D-Aspartate (NMDA) and non-N-Methyl-D-Aspartate (non-NMDA) receptors. Finally we consider the pharmacological treatment of this disorder.

Adult↗