A next-generation BRAF inhibitor overcomes resistance to BRAF inhibition in patients with BRAF-mutant cancers using pharmacokinetics-informed dose escalation.

RAF inhibitors have transformed treatment for BRAF V600-mutant cancer patients, but clinical benefit is limited by adaptive induction of ERK signaling, genetic alterations that induce BRAF V600 dimerization, and poor brain penetration. Next-generation pan-RAF dimer inhibitors are limited by narrow therapeutic index. PF-07799933 (ARRY-440) is a brain-penetrant, selective, pan-mutant BRAF inhibitor. PF-07799933 inhibited signaling in vitro, disrupted endogenous mutant-BRAF:wild-type-CRAF dimers, and spared wild-type ERK signaling. PF-07799933 ± binimetinib inhibited growth of mouse xenograft tumors driven by mutant BRAF that functions as dimers and by BRAF V600E with acquired resistance to current RAF inhibitors. We treated patients with treatment-refractory BRAF-mutant solid tumors in a first-in-human clinical trial (NCT05355701) that utilized a novel, flexible, pharmacokinetics-informed dose escalation design that allowed rapid achievement of PF-07799933 efficacious concentrations. PF-07799933 ± binimetinib was well-tolerated and resulted in multiple confirmed responses, systemically and in the brain, in BRAF-mutant cancer patients refractory to approved RAF inhibitors.

SHP2 Inhibition Sensitizes Diverse Oncogene-Addicted Solid Tumors to Re-treatment with Targeted Therapy.

Rationally targeted therapies have transformed cancer treatment, but many patients develop resistance through bypass signaling pathway activation. PF-07284892 (ARRY-558) is an allosteric SHP2 inhibitor designed to overcome bypass-signaling-mediated resistance when combined with inhibitors of various oncogenic drivers. Activity in this setting was confirmed in diverse tumor models. Patients with ALK fusion-positive lung cancer, BRAFV600E-mutant colorectal cancer, KRASG12D-mutant ovarian cancer, and ROS1 fusion-positive pancreatic cancer who previously developed targeted therapy resistance were treated with PF-07284892 on the first dose level of a first-in-human clinical trial. After progression on PF-07284892 monotherapy, a novel study design allowed the addition of oncogene-directed targeted therapy that had previously failed. Combination therapy led to rapid tumor and circulating tumor DNA (ctDNA) responses and extended the duration of overall clinical benefit. SIGNIFICANCE: PF-07284892-targeted therapy combinations overcame bypass-signaling-mediated resistance in a clinical setting in which neither component was active on its own. This provides proof of concept of the utility of SHP2 inhibitors in overcoming resistance to diverse targeted therapies and provides a paradigm for accelerated testing of novel drug combinations early in clinical development. See related commentary by Hernando-Calvo and Garralda, p. 1762. This article is highlighted in the In This Issue feature, p. 1749.

Evaluation of Virtual Reality Perimetry and Standard Automated Perimetry in Normal Children.

Purpose: The Olleyes VisuALL-K is a pediatric videogame-based static threshold perimeter using a virtual reality headset. We determined normal threshold sensitivities for the 24-2 test locations using the virtual reality perimetry (VRP) and also tested patients on the Humphrey Field Analyzer (HFA). Patient satisfaction for the two instruments was compared. Methods: This exploratory study tested 50 normal pediatric participants aged 8 to 17 years on the HFA and VRP. The main outcome measure was threshold sensitivity at the 24-2 test locations for the two instruments. Results: The mean participant age was 13.0 ± 2.6 years; 50% were female. The threshold values for VRP are reported as measured on the device and after conversion to an HFA-equivalent scale. Age-adjusted thresholds showed a mean sensitivity of 31.8 ± 1.1 dB (46.1 ± dB HFA equivalent) diminution from the maximum light intensity in the VRP and 31.0 ± 1.5 dB diminution from the maximum light intensity in the HFA; interparticipant variability in mean threshold sensitivity was 2.7 ± 0.4 dB for the VRP and 2.7 ± 0.6 dB for the HFA. The HFA demonstrated decreased threshold sensitivity with increasing eccentricity, whereas the VRP threshold did not seem to vary with eccentricity. Mild age effects on threshold sensitivity were seen in the VRP and the HFA (R2 = 0.11, P < 0.001 and R2 = 0.05, P < 0.05, respectively). The mean time to completion for VRP and HFA was 7.6 ± 1.5 and 5.3 ± 0.9 min/eye, respectively (P < 0.0001). Patient satisfaction scores favored VRP (P < 0.01) despite the longer test duration. Conclusions: The Olleyes game-based VRP and HFA can be used to map out the peripheral vision in normal children. The VRP has a higher patient satisfaction when used in children than the HFA. The portability of the test allows it to be performed in a myriad of environments, lending a flexibility that can benefit this population. Translational Relevance: This virtual reality perimetry device provides an alternative to the Humphrey Field Analyzer for children.

Association of Age-adjusted Charlson Comorbidity Index With Orbital Fungal Disease Outcomes.

PURPOSE: To determine whether the age-adjusted Charlson comorbidity index (age-CCI) in sino-orbital fungal disease patients correlates with disease-specific mortality. METHODS: Hospital billing systems at 2 academic institutions were queried for patients with ICD-9, ICD-10, and CPT codes used in fungal disease who also had orbital disease and significant visual loss. Thirty-two patients at Institution A and 18 patients at Institution B met the inclusion criteria of microbiologic or pathologic confirmation of fungal infection and completion of inpatient ophthalmology evaluation. Patients without radiographic abnormality in the sinus or orbit were excluded. Demographic, diagnostic, treatment, and outcome variables were recorded. Our primary outcome was death due to fungal disease. RESULTS: Of the 50 medical records examined, 44 patients met the criteria for fungal-related death outcome on multivariate analysis. The regression coefficient for age-CCI and fungal-related mortality was 0.242 (95% CI, 0.012-0.779) with a p value of 0.038. CONCLUSIONS: Age-CCI is significantly associated with fungal-related mortality. This relationship remains significant when controlling for 5 covariates of fungal organism phylum, presence or absence of CNS disease, exenteration, local treatment use, and presence or absence of an immunosuppressive diagnosis. Age-CCI shows promise as a clinical and research tool in the evaluation of invasive fungal disease involving the orbit.

Presentation and outcomes of orbital cellulitis caused by Group F Streptococcus.

PURPOSE: To compare the presentation and outcomes of patients with orbital cellulitis requiring surgical intervention caused by the Group F Streptococcus (GFS) versus other bacteria. We hypothesize that patients with GFS infections have a more severe presentation and worse clinical outcomes compared to infections by other bacteria. METHODS: After Institutional Review Board approval at a large academic institutional center, 70 patients with culture-positive orbital cellulitis who required surgical intervention were identified. Clinical examinations before and after surgery as well as preoperative imaging with computed tomography and/or magnetic resonance imaging were reviewed. The study measures were preoperative and postoperative vision, motility, involved sinus disease, complications, and total hospital length of stay. Multiple imputation was used for missing data. Characteristics of patients were compared using Chi-square and Wilcoxon rank-sum. RESULTS: Nineteen patients (27%) had positive cultures for GFS and 51 patients (73%) had positive cultures for other bacterial species. There was no significant difference in visual acuity, motility, or inflammatory markers in patients with GFS compared to other patients. Patients with GFS were noted to have more sinus involvement on presentation compared to patients with other bacterial infections (P = 0.007). CONCLUSION: GFS associated orbital cellulitis is associated with significantly more sinus involvement, but has similar outcomes as orbital cellulitis from other bacterial species.

Case Report: Significant Complications of Cosmetic Iris Implantation.

SIGNIFICANCE: The complications of cosmetic iris implantation may result in irreversible vision loss. Patients who obtain these implants against general medical consensus may present to providers when sequelae develop. In symptomatic patients, providers must recognize the imminent risk to vision and mitigate further ocular damage. PURPOSE: This is an observational clinical case report of a patient with significant, progressive, vision-threatening ocular pathology from prior cosmetic iris implantation, despite medical and surgical efforts to preserve vision. CASE REPORT: A 35-year-old HIV-positive man with a history of cosmetic iris implants in India 16 months prior was referred to our center. He had a history of 4 months of steroid-refractory uveitis and secondary glaucoma, with IOP measurements of more than 50 mmHg in the outpatient setting. Slit-lamp examination revealed ciliary flush, pannus formation, corneal edema, and keratic precipitates. Optical coherence tomography suggested possible retinal nerve fiber layer loss in the left eye. He was diagnosed with uveitis and glaucoma, and after a short course of IOP-lowering medication, the implants were removed sequentially. Post-operatively, his course was complicated by IOP elevation, cataract development, and corneal decompensation. This led to bilateral Ahmed tube placement, Descemet's stripping endothelial keratoplasty of the right eye, and pending cataract surgery because of now-dense bilateral cataracts. CONCLUSIONS: This case emphasizes the vision-threatening dangers of cosmetic iris implantation. It also demonstrates that sequelae may persist and develop despite implant removal and anticipatory management. Providers managing similar patients should carefully monitor for disease progression and maintain a low threshold for referral and/or decisive surgical intervention.

Teleglaucoma Initiative at a Veterans Affairs Hospital: Pilot Safety Data and Early Experience.

PURPOSE: To evaluate the safety, reliability, and efficacy of telemedicine in delivering tertiary subspecialty glaucoma care (herein referred to as teleglaucoma) to the veteran patient population. DESIGN: Prospective case series. PARTICIPANTS: Twenty patients being referred for glaucoma subspecialist opinion participated in the pilot safety study. One hundred eighteen patients participated in the secondary study of the acceptability and service efficacy of teleglaucoma. METHODS: In the pilot study, safety was assessed by determining interobserver and intraobserver consistency (Krippendorff's α). This compared an in-person assessment by a glaucoma subspecialist with the remote assessment of 2 other glaucoma subspecialists (electronic health record alone reviewed). In the secondary study, teleglaucoma was implemented whereby testing and eye examination were carried out remotely by an optometrist or comprehensive ophthalmologist, and the clinical decision was made by the glaucoma subspecialist on review of the electronic health record alone. MAIN OUTCOME MEASURES: In the pilot study, interobserver and intraobserver consistency in making a diagnosis and treatment plan (acceptable, ≥ 0.80 Krippendorff's α). In the secondary study, patient satisfaction measured by survey, wait time for teleglaucoma opinion versus wait time for in-person opinion, and time spent on teleglaucoma consultations. RESULTS: Interobserver and intraobserver consistency showed an α of 0.86 and 0.92, respectively, for diagnosis, and 0.86 and 0.85, respectively, for treatment plan. In the secondary study, patient satisfaction was 4.55 of 5.00 (5 = maximum satisfaction; range, 3.28-4.93). Improved consultation lead time was demonstrated, with the median time for a doctor to respond to an electronic consultation being 3 days, versus 43 days for an in-person visit. Teleglaucoma also demonstrated positive benefits to the health care system by reducing the time doctors spent reviewing each patient's case (history, examination findings, imaging results, visual fields; 19 minutes for teleglaucoma consultation vs. 31 minutes for in-person evaluation). CONCLUSIONS: Decisions regarding diagnoses and treatment plans between in-person consultation and the teleglaucoma program showed high reliability. Patient satisfaction was high. Additional benefits were observed in wait time for subspecialty glaucoma opinion, efficient allocation of the doctor's time, and fiscal benefit to the health care system.

Rate of Unverifiable Publications Among Ophthalmology Residency Applicants Invited to Interview.

Importance: Unverifiable publications in applications for ophthalmology residencies could be a serious concern if they represent publication dishonesty. Objective: To determine the rate of unverifiable publications among applicants offered an interview. Design: Retrospective review of 322 ophthalmology residency applications for entering classes 2012 to 2017 at Vanderbilt University School of Medicine, Nashville, Tennessee. Interventions: Full-length publications reported in the applications were searched in PubMed, Google, Google Scholar, and directly on the journal's website. Applications were deemed unverifiable if there was no record of the publication by any of these means or if substantial discrepancies existed, such as incorrect authorship, incorrect journal, or a meaningful discrepancy in title or length (full-length article vs abstract). Main Outcomes and Measures: Inability to locate publication with search, incorrect author position, applicant not listed as an author, article being an abstract and not a published paper, substantial title discrepancy suggesting an alternative project, and incorrect journal. Results: Of the 322 applicants offered interviews during the 6-year study period, 22 (6.8%) had 24 unverifiable publications. Two hundred thirty-nine of these applicants (74.2%) reported at least 1 qualifying publication; of this group, 22 (9.2%) had an unverifiable publication. The applications with unverifiable publications were evenly distributed across the years of the study (range, 2-6 per cycle; Pearson χ25 = 3.65; P = .60). Two applicants had 2 unverifiable publications each. Two of the 22 applicants (9.1%) with unverifiable publications were graduates of medical schools outside the United States. Among the unverifiable publications, the most common reason was inability to locate the publication (13 [54%]). Additional issues included abstract rather than full-length publication (5 [20.8%]), incorrect author position (4 [16.7%]), applicant not listed as an author on the publication (1 [4.2%]), and substantial title discrepancy (1 [4.2%]). One listed publication had an incorrect author position and incorrect journal (1 [4.2%]). Conclusions and Relevance: Unverifiable publications among ophthalmology residency applicants is a persistent problem. Possible strategies to modify the review process include asking applicants to provide copies of their full-length works or the relevant PMCID (PubMed Central reference number) or DOI (digital object identifier) for their publications.

Similar Performance of Trabectome and Ahmed Glaucoma Devices in a Propensity Score-matched Comparison.

PURPOSE: To apply propensity score matching to Ahmed glaucoma drainage implants (AGI) to trabectome-mediated ab interno trabeculectomy (AIT). Recent data suggest that AIT can produce results similar to AGI traditionally reserved for more severe glaucoma. METHODS: AGI and AIT patients with at least 1 year of follow-up were included. The primary outcome measures were intraocular pressure (IOP), glaucoma medications, and a Glaucoma Index (GI) score. GI reflected glaucoma severity based on visual field, the number of preoperative medications, and preoperative IOP. Score matching used a genetic algorithm consisting of age, sex, type of glaucoma, concurrent phacoemulsification, baseline number of medications, and baseline IOP. Patients without a close match were excluded. RESULTS: Of 152 patients, 34 AIT patients were matched to 32 AGI patients. Baseline characteristics including ethnicity, IOP, the number of medications, glaucoma type, the degree of visual field loss and GI were not significantly different between AIT and AGI. AIT had a preoperative IOP of 23.6±8.1 mm Hg compared with 26.5+10.6 mm Hg for AGI. At 12 months, the mean IOP was 15.0±9 mm Hg for AIT versus 15.0±4 mm Hg for AGI (P=0.8), whereas the number of drops was 2.3±2.2 for AIT versus 3.6±1.3 for AGI (P=0.016). Only 6 AIT patients (17.6%) required further surgery within the first 12 months versus 9 (28%) for AGI. Success, defined as IOP<21 mm Hg, <20% reduction and no reoperation, was achieved in 76% of AIT versus 69% of AGI (P=0.48). Complications occurred in 13% of AGI and 0.8% of AIT. CONCLUSIONS: A propensity score-matched comparison of AIT and AGI showed an equivalent IOP reduction through 1 year. Surprisingly, the AGI group required more glaucoma medications than the AIT group at 6 and 12 months.

Longer-term Baerveldt to Trabectome glaucoma surgery comparison using propensity score matching.

PURPOSE: To apply propensity score matching to compare Baerveldt glaucoma drainage implant (BGI) to Trabectome-mediated ab interno trabeculectomy (AIT). Recent data suggests that AIT can produce results similar to BGI which is traditionally reserved for more severe glaucoma. METHODS: BGI and AIT patients with at least 1 year of follow-up were included. The primary outcome measures were intraocular pressure (IOP), number of glaucoma medications, and a Glaucoma Index (GI) score. GI reflected glaucoma severity based on visual field, the number of preoperative medications, and preoperative IOP. Score matching used a genetic algorithm consisting of age, gender, type of glaucoma, concurrent phacoemulsification, baseline number of medications, and baseline IOP. Patients with neovascular glaucoma, with prior glaucoma surgery, or without a close match were excluded. RESULTS: Of 353 patients, 30 AIT patients were matched to 29 BGI patients. Baseline characteristics including, IOP, the number of glaucoma medications, type of glaucoma, the degree of VF loss and GI were not significantly different between AIT and BGI. BGI had a preoperative IOP of 21.6 ± 6.3 mmHg compared to 21.5 ± 7.4 for AIT on 2.8 ± 1.1 medications and 2.5 ± 2.3 respectively. At 30 months, the mean IOP was 15.0 ± 3.9 mmHg for AIT versus 15.0 ± 5.7 mmHg for BGI (p > 0.05), while the number of drops was 1.5 ± 1.3 for AIT (change: p = 0.001) versus 2.4 ± 1.2 for BGI (change: p = 0.17; AIT vs BGI: 0.007). Success, defined as IOP < 21 mmHg, < 20% reduction and no reoperation, was achieved at 1 year in 56% of AIT versus 55% of BGI (p > 0.05) and 50% versus 52% at 2.5 years. CONCLUSIONS: A propensity score matched comparison of AIT and BGI demonstrated a similar IOP reduction through 1 year. AIT required fewer medications.

Horse Liver Alcohol Dehydrogenase: Zinc Coordination and Catalysis.

During catalysis by liver alcohol dehydrogenase (ADH), a water bound to the catalytic zinc is replaced by the oxygen of the substrates. The mechanism might involve a pentacoordinated zinc or a double-displacement reaction with participation by a nearby glutamate residue, as suggested by studies of human ADH3, yeast ADH1, and some other tetrameric ADHs. Zinc coordination and participation of water in the enzyme mechanism were investigated by X-ray crystallography. The apoenzyme and its complex with adenosine 5'-diphosphoribose have an open protein conformation with the catalytic zinc in one position, tetracoordinated by Cys-46, His-67, Cys-174, and a water molecule. The bidentate chelators 2,2'-bipyridine and 1,10-phenanthroline displace the water and form a pentacoordinated zinc. The enzyme-NADH complex has a closed conformation similar to that of ternary complexes with coenzyme and substrate analogues; the coordination of the catalytic zinc is similar to that found in the apoenzyme, except that a minor, alternative position for the catalytic zinc is ∼1.3 Šfrom the major position and closer to Glu-68, which could form the alternative coordination to the catalytic zinc. Complexes with NADH and N-1-methylhexylformamide or N-benzylformamide (or with NAD+ and fluoro alcohols) have the classical tetracoordinated zinc, and no water is bound to the zinc or the nicotinamide rings. The major forms of the enzyme in the mechanism have a tetracoordinated zinc, where the carboxylate group of Glu-68 could participate in the exchange of water and substrates on the zinc. Hydride transfer in the Michaelis complexes does not involve a nearby water.

Quantification of Focal Outflow Enhancement Using Differential Canalograms.

PURPOSE: To quantify regional changes of conventional outflow caused by ab interno trabeculectomy (AIT). METHODS: Gonioscopic, plasma-mediated AIT was established in enucleated pig eyes. We developed a program to automatically quantify outflow changes (R, package eye-canalogram, github.com) using a fluorescent tracer reperfusion technique. Trabecular meshwork (TM) ablation was demonstrated with fluorescent spheres in six eyes before formal outflow quantification with two-dye reperfusion canalograms in six additional eyes. Eyes were perfused with a central, intracameral needle at 15 mm Hg. Canalograms and histology were correlated for each eye. RESULTS: The pig eye provided a model with high similarity to AIT in human patients. Histology indicated ablation of TM and unroofing of most Schlemm's canal segments. Spheres highlighted additional circumferential and radial outflow beyond the immediate area of ablation. Differential canalograms showed that AIT caused an increase of outflow of 17 ± 5-fold inferonasally, 14 ± 3-fold superonasally, and also an increase in the opposite quadrants with a 2 ± 1-fold increase superotemporally, and 3 ± 3 inferotemporally. Perilimbal specific flow image analysis showed an accelerated nasal filling with an additional perilimbal flow direction into adjacent quadrants. CONCLUSIONS: A quantitative, differential canalography technique was developed that allows us to quantify supraphysiological outflow enhancement by AIT.

Glaucoma Surgery Calculator: Limited Additive Effect of Phacoemulsification on Intraocular Pressure in Ab Interno Trabeculectomy.

PURPOSE: To compare intraocular pressure (IOP) reduction and to develop a predictive surgery calculator based on the results between trabectome-mediated ab interno trabeculectomy in pseudophakic patients versus phacoemulsification combined with trabectome-mediated ab interno trabeculectomy in phakic patients. METHODS: This observational surgical cohort study analyzed pseudophakic patients who received trabectome-mediated ab interno trabeculectomy (AIT) or phacoemulsification combined with AIT (phaco-AIT). Follow up for less than 12 months or neovascular glaucoma led to exclusion. Missing data was imputed by generating 5 similar but non-identical datasets. Groups were matched using Coarsened Exact Matching based on age, gender, type of glaucoma, race, preoperative number of glaucoma medications and baseline intraocular pressure (IOP). Linear regression was used to examine the outcome measures consisting of IOP and medications. RESULTS: Of 949 cases, 587 were included consisting of 235 AIT and 352 phaco-AIT. Baseline IOP between groups was statistically significant (p≤0.01) in linear regression models and was minimized after Coarsened Exact Matching. An increment of 1 mmHg in baseline IOP was associated with a 0.73±0.03 mmHg IOP reduction. Phaco-AIT had an IOP reduction that was only 0.73±0.32 mmHg greater than that of AIT. The resulting calculator to determine IOP reduction consisted of the formula -13.54+0.73 × (phacoemulsification yes:1, no:0) + 0.73 × (baseline IOP) + 0.59 × (secondary open angle glaucoma yes:1, no:0) + 0.03 × (age) + 0.09 × (medications). CONCLUSIONS: This predictive calculator for minimally invasive glaucoma surgery can assist clinical decision making. Only a small additional IOP reduction was observed when phacoemulsification was added to AIT. Patients with a higher baseline IOP had a greater IOP reduction.

Regionally Discrete Aqueous Humor Outflow Quantification Using Fluorescein Canalograms.

PURPOSE: To visualize and quantify conventional outflow directly in its anatomic location. METHODS: We obtained fluorescein canalograms in six porcine whole eyes and six porcine anterior segment cultures. Eyes were perfused with a constant pressure of 15 mmHg using media containing 0.017 mg/ml fluorescein. Flow patterns were visualized using a stereo dissecting microscope equipped for fluorescent imaging. Images were captured every 30 seconds for 20 minutes for time lapse analysis. Anterior chamber cultures were imaged again on day three of culture. Canalograms were first analyzed for filling time per quadrant. We then wrote a program to automatically compute focal flow fits for each macropixel and to detect convergent perilimbal flow patterns with macropixels grouped into 3 equal-radial width rings around the cornea. A generalized additive model was used to determine fluorescence changes of individual macropixels. RESULTS: The resulting imaging algorithm deployed 1024 macropixels that were fit to determine maximum intensity and time to fill. These individual fits highlighted the focal flow function. In whole eyes, significantly faster flow was seen in the inferonasal (IN) and superonasal (SN) quadrants compared to the superotemporal (ST) and inferotemporal (IT) ones (p<0.05). In anterior chamber cultures, reduced flow on day 1 increased in all quadrants on day 3 except in IT (p<0.05). Perilimbal ring analysis uncovered convergent perilimbal flow. CONCLUSIONS: An algorithm was developed that analyzes regional and circumferential outflow patterns. This algorithm found flow patterns that changed over time and differ in whole eyes and anterior segment cultures.

Coarsened Exact Matching of Phaco-Trabectome to Trabectome in Phakic Patients: Lack of Additional Pressure Reduction from Phacoemulsification.

PURPOSE: To compare intraocular pressure (IOP) after trabectome-mediated ab interno trabeculectomy surgery in phakic patients (T) and trabectome with same session phacoemulsification (PT) using Coarsened Exact Matching. Although phacoemulsification is associated with IOP reduction when performed on its own, it is not known how much it contributes in PT. METHODS: Subjects were divided into phakic T and PT. Exclusion criteria were follow-up for <12 months and additional glaucoma surgery. Demographics were compared by the Mann-Whitney U test and chi-squared test for continuous and categorical variables, respectively. Multiple imputation was utilized to avoid eliminating data with missing values. Groups were then matched using Coarsened Exact Matching based on age, race, type of glaucoma, baseline IOP, and number of preoperative glaucoma medications. Univariate linear regression was used to examine IOP reduction after surgery; those variables that were statistically significant were included in the final multivariate regression model. RESULTS: A total of 753 cases were included (T: 255, PT: 498). When all variables except for age were kept constant, there was an additional IOP reduction of 0.05±0.01 mmHg conferred for every yearly increment in age. Every 1 mmHg increase in baseline IOP correlated to an additional IOP reduction of 0.80±0.02 mmHg. Phacoemulsification was not found to be a statistically significant contributor to IOP when comparing T and PT (p≥0.05). T had a 21% IOP reduction to 15.9±3.5 mmHg (p<0.01) while PT had an 18% reduction to 15.5±3.6 mmHg (p<0.01). Number of medications decreased (p<0.01) in both groups from 2.4±1.2 to 1.9±1.3 and from 2.3±1.1 to 1.7±1.3, respectively. CONCLUSION: Phacoemulsification does not make a significant contribution to postoperative IOP or number of medications when combined with trabectome surgery in phakic patients.

Effect of topical loteprednol on intraocular pressure after selective laser trabeculoplasty for open-angle glaucoma.

INTRODUCTION: To determine whether there is a statistically significant difference in the decrease in intraocular pressure (IOP) after selective laser trabeculoplasty (SLT) between patients receiving a 5-7 days co-administration of loteprednol versus no loteprednol over the course of 1 year. METHODS: We conducted a retrospective chart review to evaluate use of loteprednol in patients aged 30-85 years undergoing SLT for open-angle glaucoma at our center over a 3-year period. RESULTS: Three hundred and eighteen eyes from 313 patients who underwent a 360° SLT treatment between January 2008 and August 2011 were included in the analysis. Patients who received loteprednol showed a mean reduction of 2.5 (±SE 0.3) mmHg or 11.8% (±1.5%) in IOP versus a mean reduction of 3.2 (±0.6) mmHg or 14.9% (±2.5%) in those not treated with loteprednol. This difference showed a trend toward lower IOP without loteprednol, but this was not statistically significant (p = 0.29). CONCLUSION: Postoperative use of loteprednol does not appear to significantly affect IOP in patients undergoing SLT. A randomized double-blinded study in a larger group of patients would be required to clarify this issue. Until such information is available, we recommend that individual clinical judgment be used regarding whether to use topical steroids in patients undergoing SLT.

Proteomic analysis of vitreous biopsy techniques.

PURPOSE: To compare vitreous biopsy methods using analysis platforms used in proteomics biomarker discovery. METHODS: Vitreous biopsies from 10 eyes were collected sequentially using a 23-gauge needle and a 23-gauge vitreous cutter instrument. Paired specimens were evaluated by UV absorbance spectroscopy, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and liquid chromatography tandem mass spectrometry (LC-MS/MS). RESULTS: The total protein concentration obtained with a needle and vitrectomy instrument biopsy averaged 1.10 mg/mL (standard error of the mean = 0.35) and 1.13 mg/mL (standard error of the mean = 0.25), respectively. In eight eyes with low or medium viscidity, there was a very high correlation (R = 0.934) between the biopsy methods. When data from 2 eyes with high viscidity vitreous were included, the correlation was reduced (R = 0.704). The molecular weight protein sodium dodecyl sulfate-polyacrylamide gel electrophoresis profiles of paired needle and vitreous cutter samples were similar, except for a minority of pairs with single band intensity variance. Using LC-MS/MS, equivalent peptides were identified with similar frequencies (R ≥ 0.90) in paired samples. CONCLUSION: Proteins and peptides collected from vitreous needle biopsies are nearly equivalent to those obtained from a vitreous cutter instrument. This study suggests both techniques may be used for most proteomic and biomarker discovery studies of vitreoretinal diseases, although a minority of proteins and peptides may differ in concentration.

Complement, age-related macular degeneration and a vision of the future.

Age-related macular degeneration (AMD) is one of the most well-characterized late-onset, complex trait diseases. Remarkable advances in our understanding of the genetic and biological foundations of this disease were derived from a recent convergence of scientific and clinical data. Importantly, the more recent identification of AMD-associated variations in a number of complement pathway genes has provided strong support for earlier, paradigm-shifting studies that suggested that aberrant function of the complement system plays a key role in disease etiology. Collectively, this wealth of information has provided an impetus for the development of powerful tools to accurately diagnose disease risk and progression and complement-based therapeutics that will ultimately delay or prevent AMD. Indeed, we are poised to witness a new era of a personalized approach toward the assessment, management, and treatment of this debilitating, chronic disease.

Structures of the multicomponent Rieske non-heme iron toluene 2,3-dioxygenase enzyme system.

Bacterial Rieske non-heme iron oxygenases catalyze the initial hydroxylation of aromatic hydrocarbon substrates. The structures of all three components of one such system, the toluene 2,3-dioxygenase system, have now been determined. This system consists of a reductase, a ferredoxin and a terminal dioxygenase. The dioxygenase, which was cocrystallized with toluene, is a heterohexamer containing a catalytic and a structural subunit. The catalytic subunit contains a Rieske [2Fe-2S] cluster and mononuclear iron at the active site. This iron is not strongly bound and is easily removed during enzyme purification. The structures of the enzyme with and without mononuclear iron demonstrate that part of the structure is flexible in the absence of iron. The orientation of the toluene substrate in the active site is consistent with the regiospecificity of oxygen incorporation seen in the product formed. The ferredoxin is Rieske type and contains a [2Fe-2S] cluster close to the protein surface. The reductase belongs to the glutathione reductase family of flavoenzymes and consists of three domains: an FAD-binding domain, an NADH-binding domain and a C-terminal domain. A model for electron transfer from NADH via FAD in the reductase and the ferredoxin to the terminal active-site mononuclear iron of the dioxygenase is proposed.