Biomedical subjects

A Schlossman

Publications and source records attributed to A Schlossman.

At least 19 recordsLinked to original sources

PubMed1999

Nonsurgical management of binocular diplopia induced by macular pathology.

OBJECTIVE: To treat binocular diplopia secondary to macular pathology. METHODS: Seven patients underwent evaluation and treatment. All had constant vertical diplopia caused by various maculopathies, including subretinal neovascularization, epiretinal membrane, and central serous retinopathy. Visual acuity ranged from 20/20 to 20/30 in the affected eye. All except 1 patient had a small-angle, comitant hyperdeviation with no muscle paresis. Sensory evaluation demonstrated peripheral fusion and reduced stereoacuity. Neither prism correction nor manipulation of the refractive errors corrected the diplopia. A partially occlusive foil (Bangerter) of density ranging from 0.4 to 1.0 was placed in front of the affected eye to restore stable, single vision. RESULTS: The Bangerter foil eliminated the diplopia in all patients. Two patients elected not to wear the foil; 1 patient was afraid of becoming dependent, and the other was bothered by the visual blur. Visual acuity in the affected eye was reduced on average by 3 lines. All patients maintained the same level of sensory fusion, with only 2 having reduced stereoacuity. Symptoms returned when the foil was removed or its density was reduced. CONCLUSION: Low-density Bangerter foils provide an effective, inexpensive, and aesthetically acceptable management for refractory binocular diplopia induced by macular pathology, allowing peripheral fusion to be maintained.

Adult↗

PubMed1997

In vitro and in vivo effects of tetrakisphosphonates on bone resorption, tumor osteolysis, ectopic calcification, and macrophages.

The biological effects of bisphosphonates in calcium-related disorders are attributed to the incorporation of the bisphosphonates in bone, enabling direct interaction with osteoclasts and/or osteoblasts. The high accumulation of bisphosphonates in bone, due to their high affinity to hydroxyapatite (HAP), is essential for mediating in vitro and in vivo activity. In this study we examined the activity of tetrakisphosphonates, molecules containing two P-C-P type bisphosphonate moieties connected by a carbon chain. The novel compounds were examined in a battery of in vitro and in vivo models including HAP formation and dissolution, ectopic calcification, bone resorption, tumor osteolysis, and of macrophage-like cells (anti- or pro-inflammatory properties). The inhibition of ectopic calcification was ranked as follows: geminal bisphosphonates > bisacylphosphonates > tetrakisphosphonates. Pamidronate, but not the tetrakisphosphonates, was an effective antiosteolytic agent. Neither DNTP (tetrasodium 1,9-dihydroxynonane 1,1,9,9-tetrakisphosphonate) nor the bisacylphosphonate, PiBP (pimeloylbisphosphonate) seem to possess strong macrophage suppressive or inductive effects and can be considered to be relatively inactive in terms of anti- or pro-inflammatory action. A significant anticalcification effect was caused by various phosphonates, such as the tetrakisphosphonates, but DNTP, a tetrakisphosphonate, was found toxic as it impeded somatic growth and bone development.

Animals↗

PubMed1995

Anticalcification and antiresorption effects of bisacylphosphonates.

Some geminal bisphosphonates are used clinically in a number of important bone and calcium-related diseases. This work reports the anticalcification and antiresorption effects of a series of bisacylphosphonates, nongeminal compounds with varying chain lengths having oxo groups in alpha positions relative to the phosphonic functions. We compared the activity of the novel compounds to clinically used geminal bisphosphonates, and to a bisphosphonate devoid of the oxo groups. The interaction of the compounds with calcium was studied by various in vitro and in vivo models. We found that keto groups in alpha positions to the phosphonic functions render activity. The bisacylphosphonates with a shorter chain [(CH2)n, = 4, 6] were found significantly to inhibit hydroxyapatite formation and dissolution in vitro, the calcification of bioprosthetic tissue implanted subdermally in rats, and bone resorption in the intact young animal model. The various in vitro results were found to be in good correlation with the in vivo results. Structure-activity relationship studies indicate that both bisacylphosphonates and geminal bisphosphonates are active only when at least three ionizable groups are present in the molecule. The role of the keto groups is related to their contribution to chelating calcium and/or to their electron-withdrawing influence on acidity.

Acylation↗

PubMed1994

Trabeculectomy: a modified surgical technique.

A modified surgical technique is described for trabeculectomy using contemporary limbal incisional techniques for a simplified dissection of the lamellar scleral flap, a technically easier operation, with smoothly dissected surfaces. The results and complications are comparable to those using the standard method.

Conjunctiva↗

PubMed1992

In vitro and in vivo anticalcification effects of novel bishydroxyiminophosphonates.

Some geminal bisphosphonates are used clinically for a number of important bone- and/or calcium-related diseases; however, side effects and lack of selectivity impede their wide use. This work reports the synthesis and evaluation of bishydroxyiminophosphonates (e.g., adipoyl- and suberoylbisphosphonate dioximes). These compounds significantly inhibited hydroxyapatite formation and dissolution in vitro and the calcification of bioprosthetic tissue implanted subdermally in rats. The compounds reported in this paper are less active than the structurally related bisacylphosphonates. The results of this work indicate that the introduction of oxime groups adjacent to the phosphonic function in long-chain bisphosphonates confers calcium interaction capabilities and that complete ionizability of a bisphosphonate may enhance its biological activity.

Animals↗

PubMed1992

Bisacylphosphonates inhibit hydroxyapatite formation and dissolution in vitro and dystrophic calcification in vivo.

Some geminal bisphosphonates are used clinically for a number of important bone/calcium related diseases; however, side effects and lack of selectivity impede their wide use. This work reports the synthesis and evaluation of bisacylphosphonates (e.g., adipoyl- and suberoylbisphosphonate). These compounds were found to inhibit significantly hydroxyapatite formation and dissolution in vitro and the calcification of bioprosthetic tissue implanted subdermally in rats. These are the first instances of nongeminal bisphosphonates [P-(C)n-P, n greater than or equal to 2] that have been reported to be active in calcium-related disorders. The reported bisacylphosphonates possess apparent lower toxicity, and their calcium complexes/salts have improved solubility properties. Therefore, they are of potential importance for clinical applications.

Animals↗

PubMed1983

The surgical management of intermittent exotropia in adults.

Most studies of intermittent exotropia deal primarily with children. However, the manifestations of this disorder in adults differ considerably from those in children. The case records of 44 adults (ages 15-70) who underwent surgery for intermittent exotropia were analyzed. These patients experienced a variety of preoperative symptoms including diplopia, headache, difficulty with reading, and ocular fatigue or pain. Cosmesis was a rare presenting complaint. The authors recommend that surgery in adults be conservative, aiming at slight undercorrection. Surgical management was successful in 41 of 44 patients. All patients with postoperative exodeviations under 15 delta had complete resolution of symptoms. Most patients with larger residual exodeviations did not improve symptomatically; patients with postoperative exodeviations tended to experience persistent diplopia.

Adolescent↗

PubMed1980

Visual acuity and binocularity in unilateral high myopia.

Thirty-eight patients with unilateral high myopia ranging from 5 to 19 diopters were followed up for a median of two years. All were treated with full-spectacle correction and most had occlusion. When initially examined one patient (3%) had visual acuity of 6/12 (20/40) or better, four patients (12%) had central fusion, and 24 patients (63%) were phoric. At the conclusion of the study 12 patients (32%) had visual acuities of 6/12 (20/40) or better, 17 patients (45%) had central fusion, and 29 patients (76%) were phoric. Age at the start of treatment was not a factor in the versely affect the response to amblyopia was inversely related to both final fusion and final visual acuity.

Adolescent↗

PubMed1978