Local and non-local deficits in amblyopia: acuity and spatial interactions

Amblyopic vision is thought to be limited by abnormal long-range spatial interactions, but their exact mode of action and relationship to the main amblyopic deficit in visual acuity is largely unknown. We studied this relationship in a group (N=59) of anisometropic (N=21) and strabismic (or combined, N=38) subjects, using (1) a single and multi-pattern (crowded) computerized static Tumbling-E test with scaled spacing of two pattern widths (TeVA), in addition to an optotype (ETDRS chart) acuity test (VA) and (2) contrast detection of Gabor patches with lateral flankers (lateral masking) along the horizontal and vertical axes as well as in collinear and parallel configurations. By correlating the different measures of visual acuity and contrast suppression, we found that (1) the VA of the strabismic subjects could be decomposed into two uncorrelated components measured in TeVA: acuity for isolated patterns and acuity reduction due to flanking patterns. The latter comprised over 60% of the VA magnitude, on the average and accounted for over 50% of its variance. In contrast, a slight reduction in acuity was found in the anisometropic subjects, and the acuity for a single pattern could account for 70% of the VA variance. (2) The lateral suppression (contrast threshold elevation) in a parallel configuration along the horizontal axis was correlated with the VA (R2=0.7), as well as with the crowding effect (TeVA elevation, R2=0.5) for the strabismic group. Some correlation with the VA was also found for the collinear configuration in the anisometropic group, but less suppression and no correlation were found for all the vertical configurations in all the groups. The results indicate the existence of a specific non-local component of the strabismic deficit, in addition to the local acuity deficit in all amblyopia types. This deficit might reflect long-range lateral inhibition, or alternatively, an inaccurate and scattered top-down attentional selection mechanism.     

Perioperative factors for predicting successful hysteroscopic endometrial ablation

OBJECTIVE: To investigate factors affecting the success of hysteroscopic endometrial ablation in order to improve patient counseling. STUDY DESIGN: Preoperative patient characteristics (age, parity, uterine length, and presence and location of myomas) and intraoperative factors (intracavitary findings, ablation or resection, and operator) were analyzed. Forty-three women with a uterine size of < or = 10 weeks underwent hysteroscopic endometrial ablation or resection and had a median follow-up of 20 months. All were treated with depot triptorelin, 3.75 mg, 1 month prior to the procedure. Alleviation of menorrhagia and amenorrhea was classified as treatment success. Comparative analyses were made between patients with failed vs. successful procedures and with reduced bleeding vs. those with amenorrhea following surgery. RESULTS: Thirty-seven women (86%) reported a decrease in menstrual flow or amenorrhea. In 6 patients (14%), bleeding persisted or became more severe. There were no statistically significant differences between women who had successful vs. failed procedures with regard to all preoperative and intraoperative parameters analyzed. Patients with amenorrhea were significantly older as compared to women with reduced bleeding (47.5 +/- SD 5.0) vs. 44.0 +/- SD 4.1 years, P = .03. CONCLUSION: Most women with uterine size of < or = 10 weeks may expect alleviation of menorrhagia or amenorrhea after surgery. Apart from age, all other preoparative and intraoperative factors examined had no predictive value for a successful procedure. These data are valuable for proper patient counseling before hysteroscopic endometrial ablation.     

Intraoperative mitomycin C 0.02% for pterygium: effect of duration of application on recurrence rate

PURPOSE: To compare the effect of a 3- and 5-minute intraoperative application of topical mitomycin C 0.02% on the recurrence of pterygium. METHODS: A comparative, prospective clinical design was used. The study population consisted of 134 consecutive patients with unilateral primary advanced pterygium (growth of 3 mm or more horizontally from the limbus). All underwent excision of the lesion, leaving the sclera bare. At completion of surgery, topical mitomycin C 0.02% was applied for 3 minutes in the first 60 patients (group A) and for 5 minutes in the remaining 74 patients (group B). The patients were followed for 26 months by slit-lamp biomicroscopic examination of the anterior segment. Recurrent pterygium was defined as the postoperative appearance of a fibrovascular tissue crossing the limbus. RESULTS: After 12 months of follow-up, pterygium recurred in 20 patients (33.3%) in group A and in two patients (2.7%) in group B. After 15 months, the recurrence rates were 36.6% and 5.4%, respectively, and remained unchanged at 26 months. There were no cases of drug toxicity in either group. CONCLUSIONS: Five-minute intraoperative application of a single dose of 0.02% mitomycin C is safe and more effective than a 3-minute application in recurrence of pterygium.     

Enhanced erythrocyte adhesiveness/aggregation in obesity corresponds to low-grade inflammation

OBJECTIVE: Previous studies have suggested that obesity enhances the inflammatory response, producing macromolecules involved in the induction and/or maintenance of increased erythrocyte aggregation. The objectives of this study were to evaluate the correlation between inflammation markers, erythrocyte adhesiveness/aggregation, and the degree of obesity and to assess phosphatidylserine expression on erythrocyte surface membrane of obese vs. nonobese individuals. RESEARCH METHODS AND PROCEDURES: Erythrocyte adhesiveness/aggregation in the peripheral venous blood was evaluated by using a new biomarker, phosphatidylserine expression was assessed by means of flow cytometry, and markers of inflammation were measured in 65 subjects: 30 obese [body mass index (BMI) = 41 +/- 7.7 kg/m(2)] and 35 nonobese (BMI = 24 +/- 2.7 kg/m(2)) individuals. Pearson correlations and Student's t test were performed. RESULTS: A highly significant difference was noted in the degree of erythrocyte adhesiveness/aggregation and markers of inflammation between the study groups. BMI correlated with erythrocyte adhesiveness/aggregation (r = 0.42, p = 0.001), erythrocyte sedimentation rate (r = 0.42, p = 0.001), high-sensitive C-reactive protein (r = 0.55, p < 10(-4)), fibrinogen (r = 0.37, p = 0.004), and white blood cell count (r = 0.45, p < 10(-4)). The degree of erythrocyte adhesiveness/aggregation correlated with erythrocyte sedimentation rate (r = 0.5, p < 10(-4)), high-sensitive C-reactive protein (r = 0.56, p < 10(-4)), fibrinogen (r = 0.54, p < 10(-4)), and white blood cell count (r = 0.32, p = 0.01). DISCUSSION: Our results suggest that obesity-related erythrocyte adhesiveness/aggregation is probably mediated through increased concentrations of adhesive macromolecules in the circulation and not necessarily through hyperlipidemia or phosphatidylserine exposure on erythrocyte's membrane.     

A Web-based approach to low-cost telemedicine

We have developed a Web-based application for managing e-consultations. This solves some of the problems inherent in peer-to-peer email communication. Referrals were from three hospitals in Vietnam. Each hospital was provided with Internet access for up to 4 hours a day for an initial 12-month period. In the first six months, six doctors from the Vietnamese hospitals submitted a total of 30 cases. Specialists in Sydney provided their expertise on a voluntary basis. Preliminary data suggest that the Vietnamese doctors found the system benefited their diagnostic and management decision making. Challenges have included equipment failures, language barriers and the difficulty of obtaining feedback. Successes have included the relationship building between doctors in the two countries. Preliminary results were encouraging and most of the Vietnamese doctors (five of the six) reported that they were slowly incorporating use of the system into their daily practice.     

Role of activin A in negative regulation of normal and tumor B lymphocytes

Activin A, a member of the transforming growth factor beta superfamily, has a wide spread expression pattern and pleiotropic functions. In this overview we summarize data that points to a role of activin A in negative regulation of B lineage lymphocytes. Experiments performed by us and by other groups revealed the capacity of activin A to cause apoptotic death of tumor myeloma cells, through mechanisms of cell cycle inhibition and antagonism with the survival signal of interleukin-6. In vitro studies on B lymphocyte generation from bone marrow stem cells and use of human nasal polyps as a model of inflamed tissue further demonstrate an inhibitory role of activin A in B cell spread and accumulation. These data are analyzed with respect to our model of tissue organization that we term the "restrictin model of cell growth regulation." This model assumes a morphogen-like role of activin A in the hematopoietic system. Thus, the relative concentration of biologically functional activin A, in different parts of the tissue, may determine the local B cell content and functional state of these cells within a specific microenvironment.     

Successful co‐treatment with LHRH‐agonist for ovarian over‐stimulation and cystic formation in premenopausal tamoxifen exposure

The present study evaluates the potential beneficial effect of cotreatment with LHRHagonist in resolving premenopausal tamoxifen's induced supraphysiological serum 17 estradiol levels and persistent ovarian cysts. Ultrasonographic and serum hormonal evaluations were performed before, during, and following three consecutive injections of long acting LHRHagonist administered to 14 premenopausal breast cancer patients treated with tamoxifen, who had supraphysiological serum 17 estradiol levels and simultaneous persistent ovarian cysts. Within 3 weeks of the first LHRHagonist injection, all patients had menopausal serum estradiol levels. Ovarian cysts completely disappeared within 2 months following the first injection. Following the discontinuation of LHRHagonist cotreatment, serum estradiol levels remained in physiological levels and the ovaries remained a normal size in 64.3% of the patients for 13.3 ± 11.5 months. 28.6% of the patients had a gradual reappearance of high serum estradiol levels and of ovarian cysts, and were, therefore, treated with a second course of LHRHagonist. Following the second course, serum estradiol levels remained in physiological levels and the ovaries remained a normal size for 8–15 months. It is concluded that short duration of cotreatment with long acting LHRHagonist administered to premenopausal breast cancer patients treated with tamoxifen, successfully resolved the tamoxifeninduced supraphysiological serum 17 estradiol levels and the ovarian cysts.affiliated with Sackler Faculty of Medicine, Tel Aviv University