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Antonio Sánchez

Publications and source records attributed to Antonio Sánchez.

14 recordsLinked to original sources
PubMed2006

Interface corneal edema secondary to steroid-induced elevation of intraocular pressure simulating diffuse lamellar keratitis.

PURPOSE: To describe interface corneal edema secondary to steroid-induced elevation of intraocular pressure (IOP) following LASIK. METHODS: Retrospective observational case series. Diffuse interface edema secondary to steroid-induced elevation of IOP was observed after LASIK simulating diffuse lamellar keratitis (DLK) in 13 eyes. Mean patient age was 31.4 +/- 5.3 years. Patients were divided into two groups according to provisional misdiagnosis: DLK group (group 1) comprised 11 eyes and infection group (group 2) comprised 2 eyes (microbial keratitis). Mean follow-up was 8.1 +/- 0.5 weeks. RESULTS: In the DLK group, typical diffuse haze was confined to the interface and extended to the visual axis, impairing vision in all eyes. Provisional diagnosis was late-onset DLK and topical steroids were started. Repeat examination showed elevated IOP as measured at the corneal center and periphery using applanation tonometry (mean 19.1 mmHg and 39.5 mmHg, respectively), causing interface edema with evident interface fluid pockets. Steroids were stopped and topical anti-glaucoma therapy was started. The interface edema decreased and at the end of follow-up the corneal transparency was restored and IOP dropped to normal values. The infection group demonstrated a microbial keratitis-like reaction and underwent flap lifting and interface wound debridement and biopsy with administration of fortified antibiotics and steroids. After elevated IOP was detected, steroids and antibiotics were stopped and topical anti-glaucoma therapy was started, resulting in the resolution of the interface edema. CONCLUSIONS: Interface fluid syndrome secondary to steroid-induced elevation of IOP might develop in steroid responders after LASIK with a misleading clinical picture simulating DLK or infectious keratitis. Management includes stopping topical steroids and starting topical antiglaucoma therapy.

Adult↗
PubMed2005

Decreased endocannabinoid levels in the brain and beneficial effects of agents activating cannabinoid and/or vanilloid receptors in a rat model of multiple sclerosis.

Recent studies have addressed the changes in endocannabinoid ligands and receptors that occur in multiple sclerosis, as a way to explain the efficacy of cannabinoid compounds to alleviate spasticity, pain, tremor, and other signs of this autoimmune disease. Using Lewis rats with experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis, we recently found a decrease in cannabinoid CB1 receptors mainly circumscribed to the basal ganglia, which could be related to the motor disturbances characteristic of these rats. In the present study, using the same model, we explored the potential changes in several neurotransmitters in the basal ganglia that might be associated with the motor disturbances described in these rats, but we only found a small increase in glutamate contents in the globus pallidus. We also examined whether the motor disturbances and the changes of CB1 receptors found in the basal ganglia of EAE rats disappear after the treatment with rolipram, an inhibitor of type IV phosphodiesterase able to supress EAE in different species. Rolipram attenuated clinical decline, reduced motor inhibition, and normalized CB1 receptor gene expression in the basal ganglia. As a third objective, we examined whether EAE rats also exhibited changes in endocannabinoid levels as shown for CB1 receptors. Anandamide and 2-arachidonoylglycerol levels decreased in motor related regions (striatum, midbrain) but also in other brain regions, although the pattern of changes for each endocannabinoid was different. Finally, we hypothesized that the elevation of the endocannabinoid activity, following inhibition of endocannabinoid uptake, might be beneficial in EAE rats. AM404, arvanil, and OMDM2 were effective to reduce the magnitude of the neurological impairment in EAE rats, whereas VDM11 did not produce any effect. The beneficial effects of AM404 were reversed by blocking TRPV1 receptors with capsazepine, but not by blocking CB1 receptors with SR141716, thus indicating the involvement of endovanilloid mechanisms in these effects. However, a role for CB1 receptors is supported by additional data showing that CP55,940 delayed EAE progression. In summary, our data suggest that reduction of endocannabinoid signaling is associated with the development of EAE in rats. We have also proved that the reduction of CB1 receptors observed in these rats is corrected following treatment with a compound used in EAE such as rolipram. In addition, the direct or indirect activation of vanilloid or cannabinoid receptors may reduce the neurological impairment experienced by EAE rats, although the efficacy of the different compounds examined seems to be determined by their particular pharmacodynamic and pharmacokinetic characteristics.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed2004

Effusive-constrictive pericarditis.

BACKGROUND: Effusive-constrictive pericarditis is an uncommon pericardial syndrome characterized by concomitant tamponade, caused by tense pericardial effusion, and constriction, caused by the visceral pericardium. We conducted a prospective study of its clinical evolution and management. METHODS: From 1986 through 2001, all patients with effusive-constrictive pericarditis were prospectively evaluated. Combined pericardiocentesis and cardiac catheterization were performed in all patients, and pericardiectomy was performed in those with persistent constriction. Follow-up ranged from 1 month to 15 years (median, 7 years). RESULTS: A total of 1184 patients with pericarditis were evaluated, 218 of whom had tamponade. Of these 218, 190 underwent combined pericardiocentesis and catheterization. Fifteen of these patients had effusive-constrictive pericarditis and were included in the study. All patients presented with clinical tamponade; however, concomitant constriction was recognized in only seven patients. At catheterization, all patients had elevated intrapericardial pressure (median, 12 mm Hg; interquartile range, 7 to 18) and elevated right atrial and end-diastolic right and left ventricular pressures. After pericardiocentesis, the intrapericardial pressure decreased (median value, -5 mm Hg; interquartile range, -5 to 0), whereas right atrial and end-diastolic right and left ventricular pressures, although slightly reduced, remained elevated, with a dip-plateau morphology. The causes were diverse, and death was mainly related to the underlying disease. Pericardiectomy was required in seven patients, all of whom had involvement of the visceral pericardium. Three patients had spontaneous resolution. CONCLUSIONS: Effusive-constrictive pericarditis is an uncommon pericardial syndrome that may be missed in some patients who present with tamponade. Although evolution to persistent constriction is frequent, idiopathic cases may resolve spontaneously. In our opinion, extensive epicardiectomy is the procedure of choice in patients requiring surgery.

Adolescent↗
PubMed2004

Influence of intramammary infection and non-infection factors on somatic cell counts in dairy goats.

A total of 1304 goat udder halves were sampled monthly during an entire lactation (6262 samples) with the aim of identifying factors affecting milk somatic cell count (SCC). Bacteriological analyses for identification of mastitis pathogens were carried out on all samples and SCC was also determined. All animals were examined for infection by caprine arthritis-encephalitis virus (CAEV) using a commercial ELISA test kit. Results obtained were arranged in two databases (whole-lactation average half-udder database and monthly half-udder database) and two mixed models were applied. Random effects of half udder nested into flock and fixed effects of flock, intramammary infection (IMI) status, number of kids born, length of lactation and interaction of parity with IMI status were significant for the first database. CAEV infection and its interaction with IMI status was not significant. Milk SCC was significantly increased for infected udder halves and milk from udder halves infected with minor pathogens had lower SCC than udder halves infected with major pathogens. For healthy udder halves, SCC was higher in older animals but this effect was not evident in halves with IMI. Multiple birth and short-duration lactation were factors associated with elevated milk SCC. The second mixed model considered repeated measures in time for consecutive samplings throughout lactation (stage of lactation) which was also a significant factor with increasing stage of lactation. The influence of all these factors should be taken into account in the establishment of more reliable diagnostic SCC thresholds for IMI.

Animals↗
PubMed2004

[Arrhythmia induction during atrial pacing with atrial floating electrodes].

Atrial pacing with floating electrodes primarily designed for single lead VDD systems has disadvantages attributable to the floatability of the electrodes. Body and breathing movements cause changes in the position of the atrial dipole that can lead to failure of atrial capture and sensing, and even alternation of the stimulated chamber. We report the induction of typical intranodal tachycardia episodes related to intermittent failure of atrial capture in a patient with an implanted single lead DDD pacing system. Such systems pose a substantial risk of potentially arrhythmogenic asynchronous pacing.

Aged↗
PubMed2003

Sex chromosomes pairing in two Arvicolidae species: Microtus nivalis and Arvicola sapidus.

Arvicolid rodents present both synaptic and asynaptic sex chromosomes. We analyzed the pairing behaviour of sex chromosomes in two species belonging to this rodent group (Microtus nivalis and Arvicola sapidus). At pachynema, the sex chromosomes of both species paired in a small region while the rest remain unsynapsed. Consequently at metaphase I, sex chromosomes present end-to-end association. Thus, the pairing behaviour of sex chromosomes in these species is very similar to that previously described for other arvicolid rodents and for most mammals. According to this, we propose that synaptic sex chromosomes were the ancestral condition in the family Arvicolidae, including the genus Microtus. The phylogenetic origin of the asynaptic sex chromosomes in the genus Microtus would have arisen once in the lineage that originated the species M. arvalis/agrestis and related species, while the lineage that originated the species M. oeconomous and related species conserved synaptic chromosomes. Furthermore, the phylogenetic relationships between the genus Microtus, Chionomys and Pitymys are discussed in relation to the synaptic behaviour of sex chromosomes.

Animals↗
PubMed2003

The management of stage I-II supradiaphragmatic Hodgkin's disease with chemotherapy alone.

The treatment of choice for patients with early stage Hodgkin's disease (HD) has been extended field or subtotal nodal irradiation. Remission rates of over 95% have been obtained, however, about 5% of stage I and II patients will suffer from progressive disease while on therapy and an additional 15-20% will relapse. Chemotherapy (Ch) alone has not been adequately tested in early-stage HD. In this study, all HD stage I and II patients treated with Ch alone in the University Hospital "Clínica Puerta de Hierro" between 1980 and 1997 were reviewed. Thirty-five patients were treated between 04/80 and 12/97. All patients achieved complete remission. The median follow-up was 119 months (range 21-240 months), no patients were lost at follow-up. Overall survival (OS) was 97% (IC 95%, 92-100) at 5 years and 88% (IC 95%, 75-100) at 10 years. Failure free survival (FFS) was 93% (IC 95%, 83-100) at 5 years and 66% (IC 95%, 47-86) at 10 years. Three (8.5%) patients died: two due to a second tumour (non-Hodgkin's lymphoma and myeloid acute leukaemia) and the other due to sepsis post-Ch. Univariate and multivariate analysis only associated histology subtype relative risk (RR) 4.0 nodular sclerosis (95% IC, 1.0-5.5; p:0.02) with higher relapse. Other prognostic factors did not reveal significant differences with respect to failure free or OS. In conclusion, we believe that death from HD in early-stage patients is unusual and mortality from causes other than HD occurs many years later. Outside clinical trials due to the lack of clear prognostic factors, with the exception of specific situations, patients should be informed of all the possible alternatives as well as the consequences of the treatments employed. In our experience, it appears that using Ch alone in the initial stages does not jeopardize overall patient survival, with similar results being achieved.

Adult↗
PubMed2003

Effect of prolonged vegetative reproduction of olive tree cultivars (Olea europaea L.) in mitochondrial homoplasmy and heteroplasmy.

The inheritance of mitochondrial and chloroplast genomes does not follow Mendelian laws, but proceeds by vegetative segregation. Most organisms show organelle homoplasmy, which is probably produced and maintained during sexual reproduction. We have tested the effect of prolonged vegetative multiplication in the maintenance of mitochondrial homoplasmy and the generation of heteroplasmy in cultivated olive trees, Olea europaea L. Seven trees, each representing a different variety of olive, were analysed by the study of an intergenic spacer region of the mitochondrial genome. A very high level of heteroplasmy was detected in all cases. We found multiple genome variants of the sequence analysed. The frequency of genomes with no changes in the spacer region was 11.5%. This means that 88.5% of genomes contain at least one change. The same spacer mitochondrial region was sequenced in several clones from four olive trees of a second generation of sexually reproduced trees. In these trees, many clones were identical and had no changes, which represents a clear reduction of the heteroplasmy (p < 0.001). Therefore, this work supports the relevance of the role of sexual reproduction in the maintenance of mitochondrial homoplasmy and also shows that mutations accumulate in a non-coding sequence of the mitochondrial genome when vegetative propagation is maintained for a long period of time.

Base Sequence↗
PubMed2002

Single lead DDD pacing using electrodes with longitudinal and diagonal atrial floating dipoles.

In this study, an assessment was made of the possibilities of single lead DDD pacing in two groups: a group of 15 patients in whom a lead with a longitudinal atrial "floating" dipole was implanted, and another group of 10 patients with a lead with a diagonal atrial "floating" dipole. In both groups, the electrodes were connected to a SLD generator. At discharge, atrial capture was achieved with the unipolar mode in 17 of 25 patients, whereas in the group carrying the longitudinal atrial dipole, atrial capture was achieved with the overlapping biphasic impulses (OLBI) system in 12 of 15 patients and in all 10 patients in the group with the diagonal atrial dipole. At 3 months, atrial capture was achieved with the unipolar mode in 13 of 22 patients (5.75 +/- 1.77 V/0.5 ms), whereas with the OLBI system atrial capture was achieved in 8 of 13 patients carrying the longitudinal atrial dipole (3.11 +/- 1.13 V/0.5 ms), and in 8 of the 9 patients carrying the diagonal atrial dipole (2.80 +/- 0.69 V/0.5 ms). In this study, the use of the OLBI system led to a significant reduction of atrial threshold (P < 0.0001). Phrenic stimulation is the main untoward effect reported during single lead DDD pacing, a lower incidence being detected in the group carrying the diagonal atrial dipole (10 vs 35.7%, P = NS). Other limitations of this form of pacing could result from a crossed stimulation phenomenon detected in a patient during single lead DDD pacing.

Aged↗
PubMed2002

Mapping the SRY gene in Microtus cabrerae: a vole species with multiple SRY copies in males and females.

The SRY gene is a single-copy, male-specific gene, located on the Y chromosome in most mammals. However, recently we have described the presence of multiple polymorphic copies of this gene in both males and females of the vole species Microtus cabrerae. Here, we present the chromosomal localization of SRY gene copies in this species by fluorescent in situ hybridization (FISH). This technique localized these gene copies in the short arm, and hence in the euchromatic region, of the Y chromosome. Furthermore, several copies of the SRY gene are located on the X chromosome. These copies are spread along the entire heterochromatic region of the X chromosome, occupying the whole short arm, the centromeric region, and the pericentromeric region of the long arm.

Animals↗