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Biomedical subjects

A Spierer

Publications and source records attributed to A Spierer.

At least 19 recordsLinked to original sources
PubMed1992

Secondary cataract in infants after extracapsular cataract extraction and anterior vitrectomy.

Two infants developed secondary cataract after undergoing extracapsular cataract extraction (ECCE), posterior chamber intraocular lens (IOL) implantation, posterior capsulectomy, and anterior vitrectomy. A similar complication developed in a third child, who had undergone ECCE and posterior capsulotomy. The secondary cataracts developed in these patients from 3 to 12 weeks after the primary operation. In infants, unlike adults, posterior capsulectomy and anterior vitrectomy after ECCE do not seem always to prevent secondary cataracts. In infants, the complication may be related to IOL implantation.

Anterior Eye Segment↗
PubMed1991

The role of increased intraocular pressure on upgaze in the assessment of Graves ophthalmopathy.

The significance of the increase in intraocular pressure (IOP) on upgaze in the diagnosis of Graves ophthalmopathy and its normal range are controversial. The authors measured the increase in IOP on upgaze in 69 hyperthyroid patients with Graves disease, diagnosed at 1 month to 15 years previously, to assess their clinical, laboratory, and ophthalmic state. Ninety-seven healthy subjects served as controls. The distribution of increase in IOP on upgaze values in 46 patients with noninfiltrative ophthalmopathy (classes 0 to 1) was the same as in the control group. The 23 patients with infiltrative ophthalmopathy (classes 2 to 4) had increased frequency of higher increases in IOP on upgaze values compared with the other two groups. However, because of considerable overlap, increase in IOP on upgaze was not discriminatory between the groups. Increase in IOP on upgaze correlated positively with the severity of exophthalmos. There was no correlation among age, sex, time since diagnosis, thyroid functional state, and drug therapy. The authors conclude that an increase in IOP on upgaze is a normal finding augmented by Graves infiltrative ophthalmopathy. It has no diagnostic advantage over the simple clinical signs of ophthalmopathy.

Adolescent↗
PubMed1991

Evaluation of accommotrac biofeedback training for myopia control.

A new treatment for myopia, biofeedback training for control of accommodation, has been proposed and developed over the past decade. Various reports in the literature show marked inconsistencies in the results of such treatment. A double-masked study with experimental and control groups of 15 subjects each was designed to obtain a definitive answer concerning the efficacy of this method. The parameters evaluated were visual acuity, cycloplegic and noncycloplegic retinoscopy, subjective refraction, amplitude of accommodation, and flexibility of accommodation. In all categories no significant difference was found between the control and experimental subjects. The consequences of these findings are discussed as to the benefit of treatments using this method and avenues to explore in future studies.

Accommodation, Ocular↗
PubMed1991

Etiology of reduced visual acuity in congenital nystagmus.

A study was undertaken to identify the etiologic factor of reduced visual acuity in congenital nystagmus. Fourteen children with congenital nystagmus and reduced visual acuity were examined, using a modified "E" game test. Their success rate in identifying vertical lines was compared with their success rate in identifying horizontal lines. The children identified both vertical and horizontal lines with a similar rate of success. These results may indicate that poor vision in congenital nystagmus patients is partly the result of amblyopia.

Amblyopia↗
PubMed1990

Dependence of position-effect variegation in Drosophila on dose of a gene encoding an unusual zinc-finger protein.

Position-effect variegation is the inactivation in some cells of a gene translocated next to heterochromatin, the region of the chromosome that is permanently condensed. The number of copies of the Drosophila gene Suvar(3)7 is a dose-limiting factor in this phenomenon, and seems from its sequence that it encodes a protein with five widely spaced zinc-fingers. This novel arrangement of zinc-fingers could help in packaging the chromatin fibre into heterochromatin, and also reflect a novel method of controlling the expression from DNA domains.

Amino Acid Sequence↗
PubMed1989

Outpatient topical use of povidone-iodine in preparing the eye for surgery.

Povidone-iodine 5% solution placed on the eye immediately before ophthalmic surgery within the preoperative preparation significantly reduces the conjunctival bacterial flora. In 40 patients undergoing ophthalmic surgery, the authors compared the outpatient use of povidone-iodine for 3 days before surgery with a 3-day course of a combination antibiotic ophthalmic solution (Neosporin) placed on the other eye. All patients also received topical povidone-iodine on the operating table directly preceding surgery. Cultures taken just before preparation of the operative field showed a similar reduction of bacteria by each regimen. Cultures taken after preparation but before commencement of surgery showed a further reduction for both regimens, but more for eyes previously treated with the antibiotic (P less than 0.02). To minimize the conjunctival bacterial flora before surgery, the authors continue to recommend instillation of a broad-spectrum antibiotic for 3 days before surgery, followed by application of povidone-iodine solution to the eye immediately before surgery within the preoperative preparation.

Ambulatory Care↗
PubMed1988

Binocular function after surgical alignment of infantile esotropia.

Fifty patients with infantile esotropia, randomly selected, and operated at different ages, were evaluated in regard to their final alignment and sensory results. Comparisons of the age groups above and below 36 months of age, did not reveal a difference in their postoperative alignment. Sensory testing showed that a lower percentage of binocularity was found in patients operated on and aligned after 36 months of age. Most patients showed evidence of binocularity in only one of the sensory tests that were used in this study.

Age Factors↗
PubMed1987

Ocular signs of cocaine intoxication in neonates.

We examined 13 cocaine-intoxicated neonates, proven by urine assay, by slit lamp and found that most had iris blood vessel abnormalities. Using an iris vascularity scale that ranged from Grade 0 with no visible vessels to Grade 4 with dilated and tortuous vessels, we found that the intoxicated infants had increased grades in the iris periphery and collarette (P less than .02) as compared to 36 control newborns who had no cocaine in their urine. Infants with dilated or tortuous iris vessels were more likely to be intoxicated by cocaine (P less than .01). The presence of dilated or tortuous iris vessels in a neonate should signal the physician to rule out cocaine intoxication.

Blood Vessels↗
PubMed1987

Modifiers of position-effect variegation in the region from 86C to 88B of the Drosophila melanogaster third chromosome.

Four dominant suppressor and one enhancer of variegation loci were mapped in the polytene chromosome region extending from section 86C to section 88B of the Drosophila melanogaster third chromosome using a set of deficiencies. The suppressor locus Su-var(3)14 maps in 86CD, Su-var(3)13 in 86F4-7, Su-var(3)6 in 87B4-7 and Su-var(3)7 in 87E4-5. The enhancer locus E-var(3)3 maps in 87E12-F11. Su-var(3)13, Su-var(3)6 and Su-var(3)7 are also defined by point mutant alleles originally identified by other criteria (Reuter et al. 1986). Duplications covering the suppressor loci Su-var(3)14, Su-var(3)13, Su-var(3)6 and Su-var(3)7 were found to reduce considerably the haplo-abnormal effect of heterozygous point mutants of the corresponding loci. One suppressor locus, Su-var(3)7, maps within a region which has previously been cloned. The positions of deficiency breakpoints delimiting the suppressor locus indicate that all the necessary sequences for its function are located within 10 kb of cloned DNA.

Animals↗
PubMed1987

Optic nerve trauma with prolonged blindness followed by visual-evoked potential.

An accidental deep intraorbital penetration of a radio antenna tip damaged the optic nerve and caused immediate amaurosis in a 19-year-old female with normal funduscopic, electroretinographic and computerized tomographic orbital findings. A small visual-evoked potential (VEP) recorded within 2 h of injury and in the following days revealed persistent electrical nerve conduction despite loss of vision and afferent pupillary reaction. The VEP constituted the only anticipating sign for the visual recovery which occurred after 3 days. Further increase of the VEP amplitudes preceded the visual improvement, resulting, finally, in 6/24 visual acuity with only lower nasal quadrant scotoma and slight optic disk pallor.

Adult↗
PubMed1986

Persisting accommodative esotropia.

This report examines the persistence of many cases of accommodative esotropia well beyond the expected time of resolution (age 10 to 12 years) and the potential usefulness of any associated clinical features to predict timely or delayed disappearance. In a series of 202 patients, there was no discrete age of improvement and more than half persisted after age 10 years. The results were similar for both high and normal accommodative convergence/accommodation ratio cases. Initial hyperopia did not predict persistence; subsequent increases prior to age 7 years, and decreases thereafter, were different statistically but were clinically similar. Moreover, the occurrence of inferior oblique overaction and of dissociated vertical deviation, as well as a family history of strabismus, did not predict persistence or delayed improvement.

Accommodation, Ocular↗
PubMed1986

Several hundred base pairs upstream of Drosophila hsp23 and 26 genes are required for their heat induction in transformed flies.

We have used the P-element-mediated transformation of Drosophila germ line to study the 5' DNA sequences involved in the thermal inducibility of the genes for heat shock proteins hsp23 and 26. The results are strikingly different from those previously obtained in heterologous systems. For hsp23, each successive shortening of the promoter region from 618 to 402, 321 and 263 bp clearly decreased the expression. A construct with only 149 bp was not inducible at all. For hsp26, all the regulatory elements appear to be clustered in the first 350 bp upstream from the cap site. Clones with 171 bp showed a 4- to 10-fold decrease in induction depending on the transformed line, and those with only 52 bp were not expressed. The results suggest that at least three Pelham consensus sequences are required for the full expression of these two genes. The direct involvement of one of these consensus sequences has been assessed: a 6-bp deletion within the proximal element of the hsp26 gene strongly reduced its inducibility. Our results also indicate that X-linked hsp genes exhibit either partial dosage compensation or none at all.

Animals↗
PubMed1985

Pterygium, solar ultraviolet radiation and myopia.

A retrospective study of 93 patients who underwent pterygium excision revealed a low prevalence of myopia in comparison with normal population. These results support the theory that solar ultraviolet radiation is a contributory factor in the formation in pterygium and some protection against this radiation is afforded by continuously worn myopic correction.

Female↗
PubMed1985

Diagnosis and localization of intraocular foreign bodies by computed tomography.

Computed Tomography (CT) is the only imaging modality whereby bone and anatomical soft tissue structures are clearly defined. Detection of intraocular foreign bodies (FBs) can be easily obtained by scanning in the axial plane. For the precise localization of FBs, information in two planes is necessary; this is usually achieved by adding a CT study in the coronal plane to the axial plane study. When using a superimposed grid with millimeter calibration on a zoom orbital scan, the accurate location can be calculated. This contribution is of the utmost importance in deciding upon the appropriate approach when surgical removal is indicated.

Adolescent↗