Female In-Class Participation and Performance Increase with More Female Peers and/or a Female Instructor in Life Sciences Courses.

As we strive to make science education more inclusive, more research is needed to fully understand gender gaps in academic performance and in-class participation in the life sciences. Studies suggest that male voices dominate introductory biology courses, but no studies have been done on upper-level courses. Results on achievement gender gaps in biology vary and often conflict, and no studies have been done on the correlation between participation and academic performance gaps. We observed 34 life sciences courses at all levels at a large private university. Overall, males were more likely to participate than their female peers, but these gender gaps varied from class to class. Females participated more in classes in which the instructor called on most hands that were raised or in classes with more females in attendance. Performance gender gaps also varied by classroom, but female final course grades were as much as 0.2 SD higher in classes with a female instructor and/or a female student majority. Gender gaps in participation and final course grades were positively correlated, but this could be solely because female students are more likely to both participate more and earn higher grades in classes with many females in attendance.

Learning Gains from a Recurring "Teach and Question" Homework Assignment in a General Biology Course: Using Reciprocal Peer Tutoring Outside Class.

Providing students with one-on-one interaction with instructors is a big challenge in large courses. One solution is to have students interact with their peers during class. Reciprocal peer tutoring (RPT) is a more involved interaction that requires peers to alternate the roles of "teacher" and "student." Theoretically, advantages for peer tutoring include the verbalization and questioning of information and the scaffolded exploration of material through social and cognitive interaction. Studies on RPT vary in their execution, but most require elaborate planning and take up valuable class time. We tested the effectiveness of a "teach and question" (TQ) assignment that required student pairs to engage in RPT regularly outside class. A quasi-experimental design was implemented: one section of a general biology course completed TQ assignments, while another section completed a substitute assignment requiring individuals to review course material. The TQ section outperformed the other section by ∼6% on exams. Session recordings were coded to investigate correlation between TQ quality and student performance. Asking more questions was the characteristic that best predicted exam performance, and this was more predictive than most aspects of the course. We propose the TQ as an easy assignment to implement with large performance gains.

"Cyclodiode". Trans-scleral diode laser cyclophotocoagulation in the treatment of advanced refractory glaucoma.

PURPOSE: To analyze the results of intraocular pressure (IOP) reduction by diode laser contact cyclophotocoagulation ("cyclodiode") in cases of advanced glaucoma refractory to alternative treatments. METHODS: Two hundred and ten eyes of 195 patients, ages 1 to 89 years (mean, 51 years) were followed for 3 to 30 months (mean, 10 months) after cyclodiode treatment. RESULTS: More than one treatment was given in 102 eyes (49%), and the overall mean number of treatments given per eye was 1.75 (range, 2-5). Mean pretreatment IOP was 34.1 mmHg (+/-10.6 mmHg). At last follow-up, mean IOP was 20.1 mmHg (+/-9.3 mmHg), and mean total medications was reduced from 2.3 to 1.7. Mean final IOP was lowest in patients with silicone oil glaucoma (17.3 mmHg), and the mean reduction in IOP was greatest in patients with neovascular glaucoma (23.9 mmHg). At last follow-up, visual acuity was worse than before treatment in 29% of eyes, unchanged in 60%, and better in 11%. Overall success rate (IOP < 22 mmHg) was 66% at a mean follow-up of 10 months. Phthisis occurred in one eye (0.5%), and chronic hypotony (0 mmHg < IOP < 5 mmHg for > 3 months) in a further two eyes (1%). Corneal graft decompensation followed treatment in two eyes, macular pucker occurred in one eye, and combined hyphema/vitreous hemorrhage in one patient. CONCLUSIONS: Diode laser cycloablation is relatively safe and effective at controlling IOP in eyes with advanced refractory glaucoma in the short and medium term. With the treatment parameters used, multiple applications may be needed.

Granular corneal dystrophy. Visual results and pattern of recurrence after lamellar or penetrating keratoplasty.

BACKGROUND: Granular corneal dystrophy is a rare indication for corneal transplantation. Both penetrating and lamellar keratoplasty have been recommended, but because granular corneal dystrophy is known to recur within the donor material and multiple grafts may be necessary, the best surgical option has not been clearly established. The cellular cause of the dystrophy is unknown and the authors hypothesized that the rate and pattern of recurrence within lamellar and penetrating grafts might give clues to its etiology. METHODS: The authors compared the visual outcome, rate, and pattern of recurrence after 20 penetrating keratoplasties and 11 lamellar keratoplasties for granular corneal dystrophy. RESULTS: Penetrating keratoplasty and lamellar keratoplasty have a good visual outcome in granular corneal dystrophy. Visual acuities after both procedures were not statistically different. Recurrence of the dystrophy within the graft material was almost universal within 4 years. It first appeared centrally and superficially, occasionally adopting a vortex pattern suggesting epithelial involvement. The recurrence-free interval was independent of size and type of graft performed. CONCLUSION: The authors recommend lamellar keratoplasty as a primary procedure in managing visually disabling granular corneal dystrophy if the deposits are limited to the superficial cornea. This is particularly applicable in younger patients in whom multiple procedures may be necessary over a lifetime due to recurrence of the dystrophy, and the lower morbidity rate associated with lamellar keratoplasty becomes appreciable. Although granular corneal dystrophy generally is classified as a stromal dystrophy, the pattern of recurrence is more consistent with an epithelial or tear-borne abnormality than a disease of the stromal keratocyte.

The long-term effects of 5-fluorouracil and sodium butyrate on human Tenon's fibroblasts.

The use of subconjunctival 5-fluorouracil (5-FU) in the first weeks after filtration surgery may ensure long-term bleb survival despite a continuing proliferative stimulus such as in eyes with neovascular glaucoma. In addition, long-term side effects may occur, such as increasing bleb thinning. To ascertain the long-term effects of 5-FU and sodium butyrate, an agent with differentiating and antiproliferative properties, we exposed proliferating human Tenon's capsule fibroblasts to different concentrations of the drugs. The cells were exposed to 5-FU for 1-12 d. The cells were subsequently observed for up to 30 d. Cell proliferation was assessed using cell counting and bromodeoxyuridine uptake, and cell viability was assessed with trypan blue uptake. 5-FU and sodium butyrate inhibited fibroblast proliferation during the treatment period. Higher concentrations of 5-FU (100 and 1000 micrograms/ml) for as little as 1 d resulted in no significant increase in the number of fibroblasts for at least 29 d after treatment was stopped, despite continued stimulation with serum. When treatment with sodium butyrate was stopped, there was greater recovery of proliferation. At a constant concentration of 1000 micrograms/ml of 5-FU for 3 or more days, or a concentration of 100 mmol/l sodium butyrate for 12 d, the entire fibroblast population gradually died over the 30 d period. Thus, short-term treatment with 5-FU may result in long-term inhibition of proliferation of fibroblasts. Long-term inhibition depends on the duration of treatment or on the concentration of 5-FU. Short-term treatment may be affecting the ability of the tissues at the bleb site to heal in the long term. Different dosage regimens may have advantages and are discussed.

Coexistent corneal disease and glaucoma managed by either drainage surgery and subsequent keratoplasty or combined drainage surgery and penetrating keratoplasty.

The results of penetrating keratoplasty following trabeculectomy in 26 eyes where there was coexistent corneal disease and glaucoma are presented. Patients were aged 16-80 years at the time of drainage surgery (mean = 51 years) and there was a mean of 33.5 months between trabeculectomy and keratoplasty. The mean pressure fell from 35.3 mm Hg prior to trabeculectomy to 14.9 mm Hg at the time of keratoplasty and 20 mm Hg 12 months after keratoplasty. There was a 0.45 probability of maintaining normal intraocular pressure with medication at 5 years after keratoplasty; and a similar graft survival probability. The probability of maintaining both a clear graft and a normal pressure was only 0.27 at 5 years. In another 22 eyes combined trabeculectomy and penetrating keratoplasty was performed. Patients' ages ranged from 21-82 years (mean 55) at surgery, and 73% were aphakic. The intraocular pressure dropped from a mean of 28.9 mm Hg preoperatively to 14 mm Hg at 12 months. There was a 5 year probability of 0.7 of maintaining a clear graft but if both a clear graft and normal intraocular pressure are considered then the probability falls to 0.5 at 5 years. The hazard ratio for intraocular pressure control and graft survival between the two groups suggests that combined surgery may offer a better prognosis.

Relapse following goniotomy for congenital glaucoma due to trabecular dysgenesis.

Three hundred and thirty-five eyes of 210 patients with congenital glaucoma due to trabecular dysgenesis were treated by goniotomy as the primary procedure in infancy. In 313 eyes (93.5%) glaucoma was controlled at one year following surgery. Using Kaplan Meier actuarial survival analysis we found that eyes controlled in infancy by one or more goniotomies are at risk of relapse of glaucoma for at least 15 years although 93% of eyes are still controlled five years after the initial surgery. Patients whose symptoms of congenital glaucoma presented at birth were more likely to relapse than those whose symptoms developed in the first few months of life. Eyes requiring multiple goniotomies in infancy were more likely to relapse than those controlled by a single procedure.

Refractive surgery for graft-induced astigmatism after penetrating keratoplasty for keratoconus.

Of a series of 201 corneal transplants for keratoconus over a 20-year period, 42 grafts (39 eyes of 38 patients) required further surgery because of intolerable astigmatism (range, -3 diopters [D] to -18 D; mean, 8.9 D). Relaxing incisions, compressive resuturing, and augmented relaxing incisions were the techniques used. All procedures resulted in a similar mean reduction in cylinder -3.6 to 5 D, but the outcome with augmented relaxing incisions was less predictable. Six grafts required two or more procedures for a satisfactory outcome. All patients had corrected visual acuity of 20/30 or better after surgery, and 75% had visual acuity of 20/20 or better. The cumulative time until 90% of the grafts had useful vision was 32 months after refractive surgery. Relaxing incisions offer the prospect of more rapid visual rehabilitation than compressive resuturing.

Effect of beta radiation on proliferating human Tenon's capsule fibroblasts.

The effects of different doses of beta radiation from a strontium-90 source on the proliferation of human Tenon's capsule fibroblasts were studied. The cultured fibroblasts were exposed to doses of 100, 250, 500, 750, 1000, 1500, and 3000 rads, and cell numbers were counted at days 3, 7, and 14. Treatment inhibited the proliferation of the fibroblasts. At seven days the cells exposed to 3000 rads showed a decrease relative to the starting cell numbers, and at 14 days the cells exposed to 1500 and 3000 rads showed a decrease in cell numbers. The doses of radiation which inhibited cell proliferation more than 50% (at day 7 and 14) and yet did not cause a decrease in the cell population were 500, 750, and 1000 rads. beta Radiation reduces the proliferation of human Tenon's capsule fibroblasts, and at higher doses this effect may be more pronounced one and two weeks after irradiation.

Trabeculectomy combined with beta irradiation for congenital glaucoma.

Sixty-six eyes with congenital glaucoma were subjected to trabeculectomy between July 1975 and June 1989 are presented. Thirty-one were treated with beta irradiation at the time of surgery with a strontium-90 applicator; 35 were not treated with beta irradiation. The usual dose was 750 rad. Analysis was limited to three years because of the shorter follow-up of the irradiated eyes. Failure in the two groups was compared statistically. When failure was categorised as IOP greater than 21 mm Hg, beta irradiation was found to be significantly protective with an adjusted risk ratio of 0.31 (95% confidence interval 0.11-0.90, p less than 0.05). Failure categorised as the need for additional medical treatment or further surgery showed significant protection with an adjusted risk ratio of 0.33 (confidence interval 0.12-0.94, p less than 0.05). Multiple regression models were used for the analysis of intraocular pressure; beta irradiation was associated with a significantly lower IOP at six months, one year, and three years (p less than 0.05). Other factors identified as being associated with a reduced failure rate or lower IOP were: no previous topical glaucoma medications: age over seven years; lack of previous surgery involving the conjunctiva. The results indicate that beta irradiation may have a beneficial effect on the prognosis of trabeculectomy in children with congenital glaucoma. However, because of the retrospective and observational nature of the study, the results must be regarded as tentative.

Congenital hypertrichosis lanuginosa and congenital glaucoma.

An infant with congenital hypertrichosis lanuginosa (CHL) and congenital glaucoma is presented. Both conditions are rare and have not been previously reported to occur in association.

Is raised intraocular pressure a bad prognostic sign in acute corneal graft rejection?

One hundred and forty acute corneal rejection episodes in 94 patients were studied retrospectively. Sixteen episodes in 15 eyes were associated with raised intraocular pressure (IOP) on admission, three of whom had had previously elevated IOP. At six weeks, six (37.5%) still required hypotensive therapy. Five eyes with raised IOP at rejection had lost vision at six weeks. Five of the six eyes with graft failure at review had raised IOP either pre-graft, at rejection or at follow-up. Eyes grafted for herpes simplex keratitis with hypertensive rejection episodes had a higher mean admission IOP, with a more short-lived rise than other eyes.

The role of penetrating keratoplasty in the management of microbial keratitis.

Penetrating keratoplasty was performed as an emergency procedure in 52 eyes which had perforated from acute microbial keratitis and in a further 11 where perforation had not yet occurred. The results are compared with those of keratoplasty in 33 non-infected perforations and 20 eyes where there had been microbial keratitis which had responded to medical therapy leaving a scarred cornea. This latter group had both a better five year survival (90%) compared to all the others (51%), p less than 0.05, and achieved significantly better visual acuities, p less than 0.005.

Endophthalmitis caused by exogenous nocardial infection in a patient with Sjögren's syndrome.

A 60-year-old woman receiving prednisolone therapy for Sjögren's syndrome presented with corneal perforation. Therapeutic penetrating keratoplasty was performed, but no causative organism was identified. Focal inflammatory infiltrates in both donor and host cornea and anterior uveitis developed postoperatively. Five months later the inflammation rapidly became much worse, with fulminating abscesses, and the eye was eviscerated because of severe endophthalmitis. Nocardia organisms were identified in the cornea, conjunctiva and vitreous by means of acridine orange and modified Ziehl-Neelsen stains. The infection produced both suppurative and granulomatous inflammation. Reexamination of the penetrating keratoplasty specimen with a modified Ziehl-Neelsen stain revealed a few Nocardia organisms, which suggested that infection had occurred at the time of corneal perforation.

The success of penetrating keratoplasty for keratoconus.

We report the results, over a 20 year period up to 1989, of 201 penetrating keratoplasties in 198 eyes of 158 patients. The five year graft survival was 97%. A corrected visual acuity of 6/12 or better was attained by 91%. The mean spherical equivalent refraction on removal of sutures was -2.68 Ds and the mean cylindrical correction was -5.56 Ds. The cumulative time to dispensing final refractive correction was 38 months for 90% of patients. Rejection episodes occurred in 20% of grafts and were associated with loosening of sutures and bilateral grafts. Atopic patients (28%) were not at greater risk from rejection. Graft refractive surgery was undertaken in 18% and, of these, 55% achieved 6/12 vision or better with an refractive correction which could be dispensed and tolerated within 6 months.

Intraocular surgery following penetrating keratoplasty: the risks and advantages.

Graft survival has been evaluated for patients who underwent subsequent intraocular surgery (extra-capsular cataract surgery or trabeculectomy) between 1983 and 1989. The patients were different from the majority of keratoplasty patients as evidenced by the indications for keratoplasty; corneal perforation was the indication in 24% of cases. Perforated and inflamed eyes were treated aggressively at the time of the acute event, including emergency keratoplasty and intensive topical steroids. Visco-elastic fluids were routinely used during secondary surgery and topical steroids were administered intensively post-operatively. The incidence of post-operative graft rejection was low (less than 14%). Rejection episodes were diagnosed early, prior to the appearance of a Khodadoust line, and were treated aggressively with intensive topical steroids. Glaucoma which was not controlled by topical therapy was surgically managed by trabeculectomy in the first instance. If this failed, tube drainage was performed and long-term topical steroids were administered. The only risk factor identified was uncontrolled glaucoma, P = 0.1. The probability of graft survival (at five years) was 0.83 after cataract surgery and 0.62 after trabeculectomy, but wide confidence limits indicate the difference is not significant.