Biomedical subjects

J García-Sanchez

Publications and source records attributed to J García-Sanchez.

6 recordsLinked to original sources

PubMed1999

Serum protein binding of itraconazole and fluconazole in patients with diabetes mellitus.

The protein binding of itraconazole and fluconazole in the serum of patients with insulin-dependent (IDDM) and non-insulin-dependent (NIDDM) diabetes mellitus was investigated in vitro. The unbound percentage of itraconazole in patients with IDDM and NIDDM was significantly higher than that in healthy volunteers. In contrast, there were no significant differences in fluconazole protein binding. A negative correlation was established between itraconazole protein binding and albumin concentration, and a positive correlation with free fatty acid concentration. The existence of a larger percentage of unbound itraconazole in diabetes patients could imply a change in drug disposition and an alteration in the effect of the drug. This should be taken into consideration in long duration treatment, especially in view of the non-linear kinetics of itraconazole.

Adult↗

PubMed1997

Comparative study of astrocytes in human and rabbit retinae.

Immunohistochemical location of Glial Fibrillary Acidic Protein (GFAP) was used to compare the morphology of astrocytes in vascularized and partially vascularized retinae (human and rabbit, respectively). Astrocytes in human and rabbit retinae were found in the same regions as the blood vessels. These cells in partially vascularized retinae differed from those in vascularized retina in several respects. Firstly, there were six morphological types in rabbit retina and only two in human retina. Secondly, in rabbit retinae there were astrocytes only related to blood vessels called "perivascular astrocytes" which were absent in human retinae. Thirdly, the astrocytes were located in the nerve fiber layer and ganglion cell layer in both types of retinae, but in human retinae these cells could also be seen in the internal nuclear layer. These observations demonstrate that there are many differences between astrocytes in human and rabbit retina, suggesting that rabbit retina could be used with caution as an experimental model in comparative studies with human retina.

Animals↗

PubMed1995

Influence of topical cyclosporine A and dissolvent on corneal epithelium permeability of fluorescein.

The corneal stroma is the major barrier to penetration for the lipophilic Cyclosporine A (CsA) molecule and prevents the use of the common ophthalmic solvents. At present, corn oil, castor oil and olive oil are the three most commonly used vehicles. The aim of this study was to determine the effect that topically applied CsA dissolved in different oils has on corneal epithelial permeability measured by fluorophotometry. Forty healthy volunteers, with absence of ocular or systemic disease and not receiving topical or systemic drugs were enrolled. Measurements were taken before and 45 min after the instillation of 40 microliters of a 2% aqueous solution of sodium fluorescein without preservatives. Basal corneal permeability and the permeability 24 h after the instillation of 2% CsA-olive oil, olive oil alone, 2% CsA-castor oil, castor oil alone, 2% CsA-corn oil and corn oil alone, were calculated. To prepare the topical 2% CsA, a Sandimmun oral solution (Sandoz, Basel, Switzerland) was employed under sterile conditions. We found that epithelial permeability 24 h after the instillation of any CsA formulations or solvents increased more than 6.62 times (p <0.001). No differences in corneal permeability values were found between any of the CsA formulations and the vehicles. We conclude that oils used to dissolve CsA are mainly responsible for the increased corneal epithelial permeability. No differences were found in the effects of the tested solvents on corneal epithelial permeability.

Administration, Topical↗

PubMed1994

Persistent choroidopathy in systemic lupus erythematosus.

We report a case of a rare entity, choroidopathy in association with systemic lupus erythematosus (SLE), previously described in only twelve patients to our knowledge. It manifested by multiple focal serous elevations of the sensory retina and/or serous detachments of the retinal pigment epithelium bilaterally. No retinal vascular changes were observed. The probable pathogenesis is related to choroidal vascular disease due to systemic hypertension secondary to lupus nephritis, vasculitis, or a combination of these.

Choroid Diseases↗

PubMed1992

Retinal perivascular astroglia: an immunoperoxidase study.

Different morphological types of retinal perivascular astrocytes have been studied in wholemount preparations of rabbit retina. Astrocytes were immunohistochemically demonstrated using glial fibrillary acidic protein monoclonal antibodies (GFAP clone GA-5). Three types of perivascular astrocytes were found. Type I has an ovoid perikaryon which gives rise to numerous hair-like processes, and it shows strong GFAP reactivity; these cells are associated with medium-size vessels and capillaries. Type II is star-shaped and its spherical perikaryon has a basal cone with four to ten small, protruding, radial processes; these astrocytes show high GFAP reactivity and are located on larger and medium-size vessels. Type III astrocytes show the classic, star-shaped morphology in which processes emerge directly from the perikaryon which lacks a basal cone. However, different from Types I and II, Types III astrocytes show low GFAP reactivity and are positioned between capillaries. These cells are the only ones that can contact other astrocytes of the same type to form a network.

Animals↗

PubMedDate not supplied

Endothelial morphological and functional evaluation after cataract surgery.

PURPOSE: To assess endothelial barrier function, morphological appearance and corneal thickness three months after cataract surgery in order to evaluate intraoperative endothelial damage. METHODS: Endothelial permeability was examined by fluorophotometry, and contact specular microscopy and corneal pachymetry measurements were made in 40 patients (40 eyes) with senile, non-complicated cataracts one month before and three months after cataract surgery. Twenty eyes underwent uneventful phacoemulsification (Group 1) and 20 uneventful extracapsular cataract extraction (ECCE) with continuous curvilinear capsulotomy (Group 2). Results were analyzed using the two-tailed Student's t test, analysis of variance, and multifactorial and regression analysis. RESULTS: There was a significant postoperative increase in endothelial permeability in both groups (p < 0.001), but no real differences between the postoperative values (p = 0.07). Mean cell loss was 15.2% in ECCE and 18.3% in phacoemulsification (p = 0.4). There was a significant linear correlation between ultrasound time, cell loss and functional damage. Postoperative pachymetric measurements were not significant. CONCLUSIONS: Endothelial response showed no differences between the surgical techniques. Endothelial barrier function remained disturbed in spite of the apparent morphological stabilization. Corneal pachymetry is not useful for assessing postoperative endothelial changes.

Aged↗