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Mating success of wild type and sepia mutants Drosophila melanogaster in different choice.
Mating behaviour of red-eyed (wt) and brown-eyed (sepia) Drosophila melanogaster was studied under light conditions. Mating success was directly observed in mating vials and techniques usually applied in the studies of sexual selection ("female choice" and "multiple choice"). The comparison of sexual activity of mutant and wild types clearly indicates that they are not equally successful in matings. Sepia eye colour mutation decreases sexual activity of Drosophila melanogaster males, influences the preference ability of females and decreases the number of progeny from homogamic mating of the se x se type, as well as from heterogamic copulations in which sepia females take part. Non-random mating of wild type males and sepia females (in "multiple-choice" situation), with genetically and phenotypically different individuals, could be another mechanism for conservation of genetic polymorphism in natural populations.
[One brown eye and one blue eye--bad mood of nature].
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Risk factors for age-related cortical, nuclear, and posterior subcapsular cataracts. The Italian-American Cataract Study Group.
A total of 1,008 cases and 469 controls, aged 45-79 years, were included in a clinic-based case-control study of age-related cataract in Parma, Italy, from 1987 to 1989. Associations were examined between specific types of cataract and physiologic, behavioral, environmental, and biochemical factors. Cases included subjects with pure cortical (n = 489), pure nuclear (n = 110), pure posterior subcapsular (n = 28), and mixed (n = 381) cataracts. With polychotomous logistic regression, an increased risk of cataract was found for females (cortical; odds ratio (OR) = 2.20) and persons with less than a high school education (all types; OR = 1.53), brown irises (nuclear, mixed; OR = 1.43), job locations in the sunlight (cortical, mixed; OR = 1.75), leisure time activities in the sunlight (cortical, mixed; OR = 1.45), a history of wearing a hat in summertime (posterior subcapsular, cortical, mixed; OR = 1.80), a positive family history of cataract (posterior subcapsular, cortical, mixed; OR = 1.88), a history of cortisone use (posterior subcapsular; OR = 8.39), increased red blood cell glucose-6-phosphate dehydrogenase activity (cortical, nuclear, mixed; OR = 1.36), and increased serum levels of uric acid (posterior subcapsular; OR = 1.62), lactic dehydrogenase (posterior subcapsular; OR = 1.76) and gamma-glutamyl transpeptidase (mixed; OR = 1.22). A decreased risk of cataract was found for persons with a positive history of arthritis (posterior subcapsular, nuclear, mixed; OR = 0.56) and increased handgrip strength (mixed; OR = 0.68). Findings from our study, combined with previously reported evidence, suggest that associations with educational status, cortisone use, sunlight exposure, and handgrip strength are real. Other findings require further evaluation.
[Role of recessive and dominant mutations in adaptation of the genus Rana to modern biosphere].
The populations of three anuran amphibian species (Amphibia, Anura) of the genus Rana (R. ridibunda Pall., R. arvalis Nilss. and R. temporaria L.) inhabiting the Yekaterinburg urban agglomeration were examined. The frequencies of two traits, morph striata and iris depigmentation, were estimated in these populations. The former trait, so-called morph striata, is phenotypically expressed as a light dorsomedial stripe. It is controlled by a dominant allele of autosomal diallelic gene striata in some species of Rana genus, exhibiting complete dominance. Striata individuals have a number of physiological features that confer them an advantage under conditions of natural and artificial geochemical anomalies. The second trait, iris depigmentation, is the result of a recessive mutation. The individuals homozygous for this trait have low viability. Thus, the dominant mutations promote rapid adaptation of their carriers. Conversely, the recessive mutations may reduce viability of an individual.
[Experiences with the FAMACHA-Eye-Colour-Chart for identifying sheep and goats for targeted anthelmintic treatment].
The bloodsuckling abomasal parasite Haemonchus contortus is the most pathogenic worm in sheep and goats. High prevalences of anthelmintic-resistant isolates make H. contortus difficult to control. Detecting the most anaemic animals could support a targeted selective treatment approach. Leaving the rest of the flock untreated would generate a refuge for anthelmintic-sensitive parasites. South-African researchers tried the FAMACHA-Eye-Colour-Chart for anaemic sheep and goats with good success. Field studies, carried out in Northern Germany on naturally infected sheep and goats showed, that at a comparatively low prevalence of H. contortus the FAMACHA-test proved not being sufficient in detecting all animals with high fecal egg counts. Under these conditions there was no satisfying reliability to identify small ruminants for selective deworming only based on the FAMACHAEye-Colour-Test. But if not working hours are the limiting factor, the repeated score could support the selection of pale animals in need to be treated.
[Clinical and statistical study of 100 vitiligo patients. I. Etiologic factors and clinical study].
A study of the etiological factors in 100 cases of vitiligo showed female predominance (59%) variable age of onset, absence of radial factor, moderate influence of psychological, physical or endocrine factors, the large number of subjects belonging to group B, a family history in 18% of cases. The morphology site and course of the lesions were also studied. There was no significant correlation between the course of the disease and the various etiological and clinical parameters studied.
Pupillary size and responsiveness. Implications for selection of a bifocal intraocular lens.
The authors measured the pupil sizes of 132 subjects and correlated these to selected designs of annular bifocal intraocular lenses (IOLs). Pupils were measured under five different testing conditions that simulated representative visual tasks: (1) driving at night, (2) reading in dim illumination, (3) reading in bright illumination, (4) distant viewing in indirect sunlight, and (5) distant viewing in direct sunlight. Pupil size diminished with age and with increased illumination. Because of accommodative pupillary constriction, there was little difference in pupil size measured while reading in bright indoor illumination and distant viewing in indirect sunlight. Evaluating a patient's pupil size permits the individualized estimation of the eye's bifocal function following implantation of each of the annular-design bifocal IOLs.
Pharmacokinetic basis for nonadditivity of intraocular pressure lowering in timolol combinations.
The authors determined whether the ocular absorption of topically applied timolol in the pigmented rabbit was affected significantly by coadministration with either pilocarpine or epinephrine in the same drop to explain the nonadditivity in intraocular pressure lowering (IOP) seen clinically. They instilled 25 microliters of 0.65% timolol maleate solution (equivalent to 0.5% timolol), both in the presence and absence of 2.6% pilocarpine nitrate or 1% epinephrine bitartrate, into pigmented rabbit eyes. The time course of timolol concentration in the conjunctiva, anterior sclera, corneal epithelium, corneal stroma, aqueous humor, iris-ciliary body, and lens was monitored for 360 min by using reversed-phase high-performance liquid chromatography. The area under the timolol concentration-time curve in all but one of the anterior segment tissues was reduced by 20-50% (mean, 40%) when timolol was coadministered with pilocarpine and by 20-70% (mean, 42%) when timolol was coadministered with epinephrine. Such an effect was not a result of alterations in corneal permeability or aqueous humor turnover rate, nor was it related to the extent of systemic absorption caused by pilocarpine and epinephrine. Rather, the reduction in ocular timolol absorption may have been caused by the accelerated washout of timolol by tears stimulated by the coadministered drugs and, to a lesser extent, by the loss of timolol through binding to the increased amount of tear proteins induced by the coadministered drugs. Thus, the nonadditivity in IOP lowering from timolol-pilocarpine and timolol-epinephrine combinations is probably caused by changes in precorneal timolol clearance.
Numbers of cortical vitreous cells and onset of cataracts in Royal College of surgeons rats.
Royal College of Surgeons (RCS) rats have hereditary retinal degeneration with associated posterior subcapsular opacities. A link between light, retinal degeneration, and cataracts may consist in peroxidation of polyunsaturated fatty acids of rod outer segment lipids to yield water-soluble toxic aldehydes that can traverse the vitreous and react with bow cells and posterior lens fibers. In an immune reaction to the retinal degeneration, macrophages multiply in the retina and in the cortex of the vitreous. In dystrophics, the cortical vitreous separates readily from attachments to retina, ciliary body and lens, and from the vitreous gel. This web-like structure was stained and spread on a counting chamber. Cells were counted at 15-130 postnatal days in pink- and black-eyed RCS dystrophics and in congenic controls to correlate numbers of cells, temporal and geographic patterns of retinal degeneration, and onset of opacities. Rats were reared in cyclic light (10-40 lux inside the cage) and fed a natural ingredient diet (NIH-07). Cortical vitreous cells increased markedly in pink- and black-eyed dystrophics at 50-53 days when slit-lamp detectable opacities occurred in both. The increase was 4.6-fold in pink- and 2.3-fold in black-eyed rats compared with controls. At 50-53 days, the dystrophy affected all quadrants of the retina severely in pink-eyed RCS but only the inferior periphery in black-eyed RCS. Consequently, severe degeneration in one quadrant may suffice to initiate an opacity.(ABSTRACT TRUNCATED AT 250 WORDS)
Photodynamic retinal vascular thrombosis. Rate and duration of vascular occlusion.
Dye-sensitized photochemical thrombosis is a new method of producing vascular occlusion in the eye for experimental purposes. The rate and duration of photodynamic occlusions of branch retinal vessels was measured in pigmented and albino rat eyes after intravenous injection of the photosensitizing dye, rose bengal. Selected vessels were exposed to focused, white light until vascular occlusion was observed biomicroscopically. A slit lamp was used for a light source in this procedure, allowing adjustment of spot size, shape, and orientation. Arterioles occluded more rapidly than venules, and the time required to produce vascular occlusion decreased when animals breathed pure oxygen administered by face mask. Rose bengal doses of 40 and 80 mg/kg were effective, 20 mg/kg was partially effective, and 1 and 10 mg/kg were ineffective in producing branch arteriole occlusion at a light intensity of 73.5 mW/cm2. The total light energy required to produce occlusion increased from an average of 0.06 J using 80 mg/kg to 0.50 J using 20 mg/kg of rose bengal. Lower light intensities produced vessel occlusion less rapidly (46 mW/cm2) or not at all (17.5 mW/cm2). The rate of retinal arteriolar occlusion was not affected by ocular pigmentation. The duration of branch vessel occlusion depended on length of vessel treated and did not exceed 3 days in arterioles and 4 days in venules. Histologic sections showed discrete areas of retinal and choroidal vascular thrombosis confined to the area of direct light exposure. Choroidal vascular thrombosis and outer retinal damage predominated in eyes treated at low light intensity. Thrombosis usually extended into the deep choroidal vessels in albino but not pigmented eyes.(ABSTRACT TRUNCATED AT 250 WORDS)
Clinico-pathologic correlates in Fuch's heterochromic iridiocyclitis--an iris angiographic study.
Iris Angiography in a case of Fuchs' heterochromic iridocyclitis (FHI) is described. The finding of iris angiography and hylainzed iris vessels on histopathology suggested ischemic etiology of FHI. This is the first report on Iris Angiography in a pigmented eye with Fuchs' heterochromic iridocyclitis.
Basic principles and evaluation of results of assays measuring genotoxic damage in somatic cells of Drosophila.
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Effect of flurbiprofen on the maintenance of pupillary dilation during cataract surgery.
A randomized, double-blind clinical trial was performed to evaluate the effect of flurbiprofen sodium (0.03%), a potent prostaglandin inhibitor, on the maintenance of pupillary dilation during elective extracapsular cataract extraction. Intraoperative pupillary measurements were taken before incision, after lens extraction and following cortex aspiration. The treatment group demonstrated statistically significant maintenance of pupillary area at each stage and in total (p = 0.003). The results indicate that the inhibition of prostaglandin synthesis by flurbiprofen aids significantly in the maintenance of intraoperative pupillary dilation.
Pupillary dilatation during cataract surgery--relative efficacy of indomethacin and flurbiprofen.
In a prospective, randomized, double-blind trial, we evaluated the relative efficacy of indomethacin and flurbiprofen when used as adjuvants to routinely used mydriatics for maintenance of pupillary dilatation in patients with heavily pigmented iris undergoing extracapsular cataract extraction. The drugs were administered orally as well as topically according to a fixed regimen. The pupillary diameters, measured with calipers at various surgical steps, were significantly larger at every step in the study groups in which either of the adjuvants had been used than they were in the control group (P less than .001). Flurbiprofen tended to help maintain a larger pupillary diameter in the later stages of surgery than indomethacin, but this difference was not statistically significant. We conclude that it is important to use prostaglandin synthetase inhibitors as adjuvants to routine mydriatics, and that flurbiprofen may be somewhat more effective than indomethacin in this capacity.
Factors associated with conjunctival intraepithelial neoplasia: a case control study.
Familial and environmental factors may play a role in the development of conjunctival intraepithelial neoplasia (CIN). Nineteen patients with biopsy-proven CIN completed a questionnaire to evaluate possible predisposing factors. Nineteen age-matched and sex-matched controls completed questionnaires and received slit-lamp examinations. Factors associated with a relatively increased risk of developing CIN included exposure to petroleum products, heavy cigarette smoking, light hair and ocular pigmentation, and family origin in the British Isles, Austria or Switzerland. Non-office and nonprofessional workers were more likely to develop conjunctival intraepithelial neoplasia (p = .05), as were those who were not college graduates (p = .07).
Sector pupillary dilation: an alternative technique.
Sector pupillary dilation is a method for controlled delivery of topical ophthalmic adrenergic agonists to stimulate the dilator muscle focally in patients predisposed to pharmacologically induced acute angle-closure glaucoma. Sector pupillary dilation can be achieved by applying a sterile cotton-tipped applicator moistened with 2.5% phenylephrine ophthalmic solution at the 6:00 o'clock limbus. A pilot study (N = 2) was conducted of one blue-eyed subject (M, age 38 years) and one brown-eyed subject (F, age 36 years) using drug contact times of 5 to 30 s in 5-s intervals. The horizontal and vertical pupil diameters were measured using photographs taken every 10 min for 1 h and every 20 min for the second hour. Sector pupil dilation developed with all application times. For the blue-eyed subject maximum sector dilation (delta = V-H = 1.5 mm) occurred with a 20-s contact time and peaked after 40 min. For the brown-eyed subject, the sector dilation effect was less marked and did not demonstrate a clear-cut peak time.
Uveal melanoma in relation to ultraviolet light exposure and host factors.
We conducted a case-control interview study among 1277 subjects (407 patients, 870 controls selected by using random digit dial) in 11 western United States to determine whether uveal melanoma and cutaneous melanoma shared common risk factors. After adjustment for other factors, the risk of uveal melanoma was increased for those with green, gray, or hazel eyes [relative risk (RR) = 2.5, P less than 0.001] or blue eyes (RR = 2.2, P less than 0.001) when compared to brown. A tendency to sunburn after 0.5 h midday summer sun exposure increased risk for uveal melanoma (burn with tanning RR = 1.5, P = 0.02; burn with little tanning RR = 1.8, P less than 0.001; burn with no tanning RR = 1.7, P = 0.002); as did exposure to UV or black lights (RR = 3.7, P = 0.003); and welding burn, sunburn of the eye, or snow blindness (RR = 7.2, P less than 0.001). An association with uveal melanoma was also noted with an increasing number of large nevi (P = 0.04 for trend), although the individual risk estimates were not remarkable. These data suggest that host factors and exposure to UV light are risk factors for uveal melanoma.