Fluorescent antibody localization of Microciona prolifera aggregation factor and its baseplate component.

Specific rabbit antisera were prepared against purified aggregation factor and its membrane-associated receptor, baseplate, derived from the marine sponge. Microciona prolifera. They were utilized in conjunction with fluorescent-labeled goat anti-rabbit IgG in an assay to demonstrate the surface localizations of both components. The specificity of antibody preparations for AF and BP was demonstrated through inhibition of the rotation-mediated assay by homotypic antibody. This study confirms the presence of aggregation factor on the surface of disaggregated sponge cells maintained in the presence of the divalent cations, Ca++ and Mg++, and its absence when cells are maintained in Ca++ and Mg++-free seawater. The location of BP could also be demonstrated on the cell surface. Aggregation factors and baseplate appear to be heavily distributed on archeocytes and choanocytes, but are localized less intensely on gray cells. Gray cells are typified by yellowish autofluorescence of their intracellular granules in stained and control preparations. The reaction of anti-Microciona aggregation factor with its homotypic factor appeared to be species specificity judged by immunofluorescence assays and by inhibition of rotation-mediated assay by anti-homotypic AF since antibodies prepared against heterotypic AF preparations were unreactive.

Appreciation of metaphoric alternative word meanings by left and right brain-damaged patients.

Appreciation of metaphoric and nonmetaphoric alternative word meanings was assessed in 19 aphasic, left (LHD) and 15 non-aphasic, right (RHD) hemisphere brain-damaged stroke patients. With the one exception in the aphasic group, all patients were male. In an unspeeded sorting task, subjects responded on the basis of less frequent, alternative meanings of polysemous target words. Targets were either polysemous adjectives (e.g. "warm") having metaphoric alternative meanings (loving) or polysemous nouns (e.g., "pen") having non-metaphoric alternative meanings (writing implement, cage). Both patient groups performed worse overall than a group of nonbrain-damaged control subjects. Relative to the RHD patients, LHD patients showed a spared appreciation of metaphoric alternative meanings. In addition, LHD, but not RHD, patients performed better on metaphoric adjective trials when there was high similarity between a word's dominant and (metaphoric) alternative meaning. The results suggest a pervasive insensitivity of RHD patients to alternative interpretations of linguistic units, and a special role for the intact right hemisphere in lexical-semantic processes related to metaphor comprehension.

Sympathetic swelling response of the control eye to soft lenses in the other eye.

PURPOSE: To compare central corneal swelling and light scatter after 8 hours of sleep in eyes wearing high- and low-Dk hydrogel lenses and to the contralateral control eyes. METHODS: Twenty neophyte subjects wore a Lotrafilcon A (Dk, 140; Ciba Vision, Duluth GA) silicone hydrogel lens and an Etafilcon A (Dk, 18; Acuvue; Vistakon, Jacksonville, FL) 58% water content hydrogel lens of similar center thickness in random order in the right eye only, for overnight 8-hour periods. The contralateral nonwearing left eyes served as controls. Central corneal thickness was measured using an optical pachometer and light scatter using a Van den Berg stray-light meter before lens insertion, after lens removal on waking, and every 20 minutes for the next 3 hours. RESULTS: Central corneal swelling induced by the Etafilcon A lens on eye opening was significantly higher than with the Lotrafilcon A lens (8.66%+/-2.84% versus 2.71%+/-1.91%; P<0.00001). Light scatter induced by the Etafilcon A lens on eye opening was significantly higher than with the Lotrafilcon A lens (46.09+/-5.62 versus 42.78+/-6.07 Van den Berg units, P = 0.0078). The swelling of the control eyes paired with the Etafilcon A lens-wearing eyes was also slightly but significantly higher than that of the control eyes paired with the Lotrafilcon A lens-wearing eyes (2.34%+/-1.26% versus 1.44%+/-0.91%; P = 0.0002). Light-scatter measurements were not significantly different between control sets of eyes but showed the same trend. CONCLUSIONS: In neophyte subjects, corneal swelling of the contralateral control eyes appears to be influenced by the swelling of the fellow lens-wearing eyes-that is, the swelling of the contralateral control eye was significantly lower when there was less swelling of the fellow eye wearing the high-Dk lens. Although there was no statistically significant difference in light-scatter measurements between the control sets of eyes, a trend similar to the corneal swelling results was observed, which could be used to support the suggestion that this may be a sympathetic physiological response rather than an unusual sampling coincidence.

Effects of luminance on the visual acuity of strabismic and anisometropic amblyopes and optically blurred normals.

Evidence is accumulating to suggest fundamental differences between strabismic and anisometropic amblyopia. We explored differences in these amblyopes by assessing the effects of luminance on optotype acuity, using targets that ranged from photopic to low mesopic levels. Our results show that reducing luminance has less of a detrimental effect on the acuity of strabismic than anisometropic amblyopic eyes. Furthermore, the effect of decreasing luminance on the acuity of optically blurred normal eyes mimicked the effect we found for anisometropic amblyopic eyes. These results are consistent with the hypothesis that the fundamental deficit in anisometropic amblyopia is impaired resolution while in strabismic amblyopia the fundamental deficit is impaired spatial directionalization.

The Cyclops effect in adults: sighting without visual feedback.

When asked to look through a tube, younger children place it at the bridge of the nose, and not over one eye: the Cyclops effect. This is a natural response to a median plane egocenter. With maturity, the Cyclops effect disappears as we learn to overcome the consequences of an egocenter between the two eyes, and instead, to use the "preferred" eye. We videotaped adults (n = 14) and children with normal vision (n = 30), children with comitant strabismus (n = 14), and adults and children (n = 14) with one eye enucleated as they attempted to look through a plastic tube. Immediately in front of the face was a liquid crystal window that could be either transparent or opaque. As the tube was raised, the window was made opaque--blocking sight of the target, their hands, and the tube. Most binocular observers placed the tube approximately at the bridge of the nose. This was significantly different from the response of the enucleated observers who put the tube 75% of the way to the remaining eye (P = 0.0001). All observers align, on average, with the measured location of their egocenter when asked to perform a monocular task without visual cues. Deprived of visual feedback, binocular observers show the Cyclops effect, regardless of age.

Diurnal variation of corneal and corneal epithelial thickness measured using optical coherence tomography.

PURPOSE: To determine the feasibility of optical coherence tomography (OCT) measurement of overnight corneal swelling and de-swelling and, specifically, to examine overnight changes in the corneal epithelium and recovery during the day. METHODS: Ten healthy volunteers were recruited. Corneal OCT imaging was performed at 10:00 PM (baseline), 8:30 AM, and every 2 hours thereafter until 4:30 PM. Either the right or left eye was taped shut (using a gauze pad and surgical tape) until the 8:30 AM session of the next day. Measurements were made along a 1-mm strip centered on the visual axis. RESULTS: At baseline, there were no differences in corneal or epithelial thickness between control and experimental eyes (all p > 0.05). Immediately after patch removal, corneal and epithelial thicknesses of patched eyes were higher than the baseline (all p < 0.05). In patched eyes, the cornea and epithelium swelled 5.5% and 8.1% overnight, respectively (p > 0.05). Two hours later, the epithelial thickness of the experimental eyes recovered to baseline level (p > 0.05), but corneal thickness did not reach to baseline level until 4 hours after patch removal. For control eyes, there were no differences compared with baseline (all p > 0.05). CONCLUSION: Both cornea and corneal epithelium experience proportionately similar amounts of overnight swelling. Recovery of overnight swelling may be slower for the cornea than for the epithelium. OCT provides valuable information about anterior segment morphometry.

A noncontact pneumatic esthesiometer for measurement of ocular sensitivity: a preliminary report.

PURPOSE: The aim of this investigation was to evaluate a prototype noncontact pneumatic esthesiometer for measuring sensitivity of the eye. METHODS: To evaluate the instrument's repeatability, central corneal sensitivity was recorded on two separate occasions with a 24-h interval between the two measures. In a separate experiment, corneal edema was induced with a thick hydrogel lens, and the eye was closed and patched. Corneal sensitivity was measured before wearing the lenses for 3 h, immediately after lens removal, and 15 min later. Corneal sensitivity also was measured before the instillation of a single drop of proparacaine (Alcaine, 0.5%) and at 2 and 18 min later. Sensitivity was measured at the corneal apex and at a temporal conjunctival location 3 mm from the limbus. RESULTS: A high correlation was found between days 1 and 2 (r = 0.90; p = 0.0001). The coefficient of repeatability (COR = 0.87 mm Hg) showed that 95% of the difference between test and retest measures were between +/-0.87 mm Hg. Corneal sensitivity decreased by 55% after lens-induced corneal swelling and by 159% after instillation of the topical anesthetic. Central corneal sensitivity was found to be significantly higher than that of the temporal conjunctiva (p = 0.0001). CONCLUSION: We conclude that this pneumatic esthesiometer provides repeatable and reliable measures of ocular-surface sensitivity.

Recovery from hyperemia after overnight wear of low and high transmissibility hydrogel lenses.

PURPOSE: To measure the limbal vascular response after 8 hours of eye closure while wearing high and low permeability lenses compared to control eyes without lenses. METHOD: Twenty neophyte participants wore lotrafilcon A silicone hydrogel lenses (HDk; Dk = 140) or etafilcon A hydrogel lenses (LDk; Dk = 18). On two different nights the lenses were randomly worn for 8 hours during sleep in the right eyes only. Left eyes were non-lens wearing controls. Biomicroscopic images of the temporal limbal area were videotaped at baseline, on eye opening and every 20 minutes for 3 hours. A masked observer graded digitized images of the limbal area. RESULTS: On waking and after lens removal there were no differences in hyperemia between the HDk and LDk lens wearing eyes. There were also no differences at any time between the HDk lens wearing eyes and their control eyes (p > 0.05). On waking the eyes wearing the LDk lens were more hyperemic compared to baseline (p < 0.001) and compared to their control eyes at 20 (p < 0.001) and 180 minutes (p = 0.01), indicating slower recovery from hyperemia. The HDk lens wearing eyes recovered to their baseline levels by 180 minutes (p = 0.99), compared to the LDk lens wearing eyes, which had not recovered to baseline levels by 180 minutes (p = 0.04). CONCLUSION: The reduction in hyperemia over time of the HDk lens wearing eyes was the same as the controls. The LDk lens wearing eyes were more hyperemic than the controls on waking and the reduction in hyperemia over time was slower. This suggests that the slower recovery from hyperemia may be affected by the lower oxygen transmissibility of the LDk lens.

Screening for childhood physical and sexual abuse among outpatient substance abusers.

Research demonstrates that substance-abusing individuals report substantially higher rates of childhood sexual and physical abuse than the general population. This study sought to test a method of identifying substance-abusing clients with histories of childhood sexual and/or physical abuse and to explore the differences between those reporting childhood abuse and those not. Files of substance abusing clients from two distinct time periods were examined for reports of childhood abuse. At Time 1 (n = 399) clients were not systematically asked about experiences of childhood abuse, and at Time 2 (n = 305) clients were routinely asked about this issue. Results indicate that significantly more male and female clients disclosed childhood abuse at Time 2. Additionally, male clients reporting childhood abuse appeared more distressed than those not reporting abuse; female clients reporting childhood abuse did not appear more distressed than their counterparts.

Ultrasonically guided transvaginal oocyte recovery from calves treated with or without GnRH.

We investigated the effect of GnRH given after gonadotropin stimulation on follicle growth and oocyte quality in young calves in a transvaginal oocyte recovery program. A 60 mg MPA pessary was inserted into each of nineteen 5-mo-old Friesian calves for 7 d; on Day 5 they received 140 mg, s.c. FSH (Folltropin) and 200 IU, i.m. PMSG and on Day 8 ten of the calves received 40 micrograms, i.m. GnRH (Fertagyl). Follicles were measured and aspirated on Day 9 using an ultrasound unit with a 6 MHz transvaginal probe (Toshiba). Oocytes from individual calves were recovered, graded and cultured in maturation media for 2 h (+GnRH group) or 22 h (-GnRH group), then fertilized and cultured for 6 d in SOF containing 0.8% BSA and amino acids. Oocyte viability (Class A,B or C) and embryo morphology were recorded. This procedure was repeated on the 19 calves plus 5 others 1 m.o. later, after random allocation to their respective groups. Approximately 70% of the calves responded to gonadotropin stimulation (> 2 follicles over 5 mm in diameter). Calves receiving GnRH tended to have both a higher number of follicles > 2 mm in diameter (27.1 vs 18.7) and of aspirated follicles (22.0 vs 14.1); however, there was a large variability between individuals (0 to 83 follicles and 0 to 73 aspirated). The total number of oocytes collected (10.8 vs 10.9) was not affected by GnRH treatment, probably due to the poor recovery rates in the highly stimulated calves from the +GnRH group, but GnRH did improve the proportion of viable oocytes (6.5 vs 4.1) due to a lower number of Class E oocytes (1.4 vs 4.5; P < 0.05). In the GnRH group, 40% of the viable oocytes had matured at the time of collection versus 0% in the group not treated with GnRH. The necessity of different culture runs between times and treatments prevented any meaningful comparison between groups for embryo development. Following the transfer of 19 morula/blastocyst-stage embryos to recipients, 3 pregnancies were detected by ultrasound examination on Day 60, with 1 oocyte originating from the +GnRH group and 2 from the -GnRH group.

The collection of oocytes from bovine ovaries.

Various needle sizes (17- and 20-g) and aspiration pressures (25, 50, 75 and 100 mmHg) were used to aspirate a total of 5,827 ovarian follicles from bovine ovaries from a slaughterhouse source to assess the impact on the quantity and quality of recovered immature oocytes. The cumulus oocyte complexes (COC's) were graded according to the presence and consistency of cumulus cells surrounding the oocyte and the data analyzed using general linear models. Overall recovery rates and the recovery of oocytes considered viable for IVM/IVF procedures (Classes A, B and C) were both significantly higher using a 17-g needle than a 20-g needle (P < 0.01). As the vacuum pressure increased so did the recovery rate of the total number of oocytes, although the number of viable oocytes reached a maximum at a calculated vacuum pressure of 55 mmHg for the 17-g needle and 77 mmHg for the 20-g needle, with an increased incidence of denuded oocytes at higher vacuum pressures. In a second experiment conducted on 1, 473 follicles, no significant difference was found between 17-g double (flushing) and 17-g single lumen needles in the recovery rate of either the total number or number of viable oocytes when using a vacuum pressure of 50 mmHg.

Case report: Chalazion and its features visualized by ultrahigh resolution optical coherence tomography.

PURPOSE: The purpose of this case report is to highlight the clinical characteristics of a recurrent chalazion through the use of digital photography and ultra-high resolution optical coherence tomography (UHROCT). CASE REPORT: A single case is presented, along with digital biomicroscopic photographs and UHROCT images. DISCUSSION: A review of the literature describing the histopathological and associations of chalazia and other disorders, suggest it may be possible to differentiate different eyelid conditions based on their clinical manifestations and appearance on UHROCT tomograms. Based on the images presented here, it appears that this case is typical of a post-menopausal incidence of chalazion and risk for acne rosacea.

Association of participation in a mindfulness programme with bowel symptoms, gastrointestinal symptom-specific anxiety and quality of life.

BACKGROUND: Stress perception and GI-specific anxiety play key roles in irritable bowel syndrome (IBS). Mindfulness-based stress reduction (MBSR) is a widely available stress reduction course, which has not been evaluated for IBS. AIM: To determine whether participation in MBSR is associated with improvement in bowel symptoms, GI-specific anxiety, and IBS-Quality of Life. METHODS: This is a prospective study of 93 participants in MBSR. We applied measures of Rome III IBS status, bowel symptoms (IBS-Severity Scoring System, IBS-SSS), IBS-Quality of Life (IBS-QOL), GI-specific anxiety (Visceral Sensitivity Index, VSI), mindfulness (Five Facet Mindfulness Questionnaire-FFMQ), and functional status (SF-8) at baseline and 2 and 6 months after enrolment. RESULTS: At 2 months, participation in MBSR was associated with small nonsignificant changes in IBS-SSS, IBS-QOL and VSI: d = -0.25, d = 0.08, d = -0.16, respectively. At 6 months, there was no significant change in IBS-SSS (d = -0.36); whereas for IBS-QOL and VSI there were significant improvements (IBS-QOL: d = 0.33, P = 0.044; VSI: d = -0.40, P = 0.014). For patients meeting Rome III IBS criteria (n = 43), changes in IBS-SSS, IBS-QOL and VSI were not statistically significant, but there was a significant correlation between the change in VSI and the change in FFMQ across the three time periods (r = 0.33). CONCLUSIONS: Participation in MBSR is associated with improvement IBS-related quality of life and GI-specific anxiety. Randomised controlled trials are warranted to further assess the role of MBSR for IBS symptomatology.

Eccentric variation of corneal sensitivity to pneumatic stimulation at different temperatures and with CO2.

The purpose was to measure corneal sensitivity at multiple corneal positions using pneumatic stimuli, at room temperature and at ocular surface temperature (with and without CO(2) added), in 15 healthy participants. Sensitivity of central, mid-peripheral, and peripheral cornea was measured using a computer-controlled modified Belmonte esthesiometer to deliver pneumatic cool (air at 20 degrees C), mechanical (air at 50 degrees C), and chemical stimuli (air at 50 degrees C with CO(2) added). The ascending method of limits and method of constant stimuli were adopted to determine the threshold to these stimuli at each location. Sensitivity across the cornea using pneumatic stimuli at different temperatures and chemical stimuli varied only slightly. These patterns of variation are different to what has been previously reported using Cochet-Bonnet esthesiometry.

PTSD symptoms, substance use, and vipassana meditation among incarcerated individuals.

The present study evaluated whether Posttraumatic Stress Disorder (PTSD) symptom severity was associated with participation and treatment outcomes comparing a Vipassana meditation course to treatment as usual in an incarcerated sample. This study utilizes secondary data. The original study demonstrated that Vipassana meditation is associated with reductions in substance use. The present study found that PTSD symptom severity did not differ significantly between those who did and did not volunteer to take the course. Participation in the Vipassana course was associated with significantly greater reductions in substance use than treatment as usual, regardless of PTSD symptom severity levels. These results suggest that Vipassana meditation is worthy of further study for those with comorbid PTSD and substance use problems.

Vision thresholds from psychometric analyses: alternatives to probit analysis.

Vision scientists and clinicians regularly obtain measures of vision and determine a person's vision threshold by choosing one of numerous methods of analysis. Analytical methods differ in their presumptions about the measures, in their complexity and in the ease of obtaining the threshold estimate. In light of these differences among so-called methods of psychometric analysis, the question is, "Do various analytical methods provide essentially equivalent vision threshold estimates or are there consequential differences that require consideration?" Measures of visual acuity, motion processing, and texture processing were obtained from 20 subjects. Each set of measures was analyzed by five psychometric methods: Logit Analysis, Normit Analysis, and linear regression of z-score transformed, logit transformed and untransformed probabilities vs. stimulus strength. The resulting thresholds were compared to the threshold obtained from Probit Analysis, which was used as a reference or "gold standard." Thresholds from the procedures were remarkably similar to those from Probit Analysis. In addition, examination of the speed of the procedures revealed that Probit Analysis was up to 10 times slower than some of the others. Considering the similarity of thresholds, the speed of computation, and the ease of implementation, Logit and Normit Analyses especially provide effective alternatives to the current gold standard, Probit Analysis, for the estimation of psychometric thresholds. In addition, z-score, logit, and linear regressions also produced unbiased threshold estimates under many circumstances, but the latter method should be applied with some caution.

Effect of asymmetry on calculations of convergence in prism diopters.

Calculations of convergence in units of prism diopters are based on an assumption that convergence is symmetrical, that is, the visual axes intersect on the median plane. The effect of departure from symmetrical convergence is shown to produce systematic errors in calculations of convergence distance, if the convergence angle is constrained to be constant. On the other hand, if the convergence distance is constrained to be constant, departure from symmetry results in a systematic reduction in the convergence angle. Because these errors are disregarded in the specification of convergence in prism diopters, care should be taken in using these units for larger amounts of asymmetrical convergence.

The relationship between eye position and egocentric visual direction.

Hering's model of egocentric visual direction assumes implicitly that the effect of eye position on direction is both linear and equal for the two eyes; these two assumptions were evaluated in the present experiment. Five subjects pointed (open-loop) to the apparent direction of a target seen under conditions in which the position of one eye was systematically varied while the position of the other eye was held constant. The data were analyzed through examination of the relationship between the variations in perceived egocentric direction and variations in expected egocentric direction based on the positions of the varying eye. The data revealed that the relationship between eye position and egocentric direction is indeed linear. Further, the data showed that, for some subjects, variations in the positions of the two eyes do not have equal effects on egocentric direction. Both the between-eye differences and the linear relationship may be understood in terms of individual differences in the location of the cyclopean eye, an unequal weighting of the positions of the eyes in the processing of egocentric direction, or some combination of these two factors.

Should level of measurement considerations affect the choice of statistic?

The belief that the level of measurement (nominal, ordinal, interval, ratio) achieved in the data constrains the type of statistic that may be used legitimately for analysis is examined in general, and in an optometric-vision science context. Theoretical considerations indicate that statistical statements about the data may be made independently of the level of measurement, and that although researchers must be concerned about the quality of their measurement, the role of measurement theory is in the interpretation of the meaning of the investigation's results as a whole not in the governance of the choice of statistic. Empirical studies indicate that measurement considerations can be ignored for the purposes of testing the null hypothesis with little or no resultant error. Finally, adherence to the belief that level of measurement considerations limits statistical choice would result in the use of generally less powerful statistical tests--an undesirable and, all things considered, an unwarranted consequence.