Chromosomal double-strand breaks (DSBs) are resected by 5′-nucleases to form 3′ single-strand DNA (ssDNA) substrates for binding by homologous recombination and DNA damage checkpoint proteins. Two redundant pathways of extensive resection were described both in cells 1-3 and in vitro 4-6, one relying on Exo1 exonuclease and the other on Sgs1 helicase and Dna2 nuclease. However, it remains unknown how resection proceeds within the context of chromatin where histones and histone-bound proteins represent barriers for resection enzymes. Here, we have identified the yeast nucleosome remodeling enzyme Fun30 as novel factor promoting DSB end resection. Fun30 is the major nucleosome remodeler promoting extensive Exo1- and Sgs1-dependent resection of DSBs while the RSC and INO80 chromatin remodeling complexes play redundant roles with Fun30 in resection adjacent to DSB ends. ATPase and helicase domains of Fun30, which are needed for nucleosome remodeling 7, are also required for resection. Fun30 is robustly recruited to DNA breaks and spreads around the DSB coincident with resection. Fun30 becomes less important for resection in the absence of the histone-bound Rad9 checkpoint adaptor protein known to block 5′ strand processing 8 and in the absence of either histone H3 K79 methylation or γ-H2A, which mediate recruitment of the Rad9 9, 10. Together these data suggest that Fun30 helps to overcome the inhibitory effect of Rad9 on DNA resection.

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Purpose To compare corneal sensitivity in tear dysfunction due to a variety of causes using contact and non-contact esthesiometers and to evaluate correlations between corneal sensitivity, blink rate and clinical parameters. Design Comparative observational case series. Methods Ten normal and 33 subjects with tear dysfunction [meibomian gland disease (n = 11), aqueous tear deficiency (n = 10) - without (n = 7) and with (n = 3) Sjögren syndrome (SS) and conjunctivochalasis (n = 12)] were evaluated. Corneal sensitivity was measured with Cochet-Bonnet and air jet esthesiometers and blink rate by electromyelography. Eye irritation symptoms, tear meniscus height, tear break-up time (TBUT), and corneal and conjunctival dye staining were measured. Between group means were compared and correlations calculated. Results Compared with control (Cochet-Bonnet 5.45 mm, air esthesiometer 3.62 mg), mean sensory thresholds were significantly higher in aqueous tear deficiency using either Cochet-Bonnet (3.6 mm; P = 0.003) or air (11.7 mg; P = 0.046) esthesiometers, but were not significantly different in the other groups. Reduced corneal sensitivity significantly correlated with more rapid TBUT and blink rate, and greater irritation and ocular surface dye staining with one or both esthesiometers. Mean blink rates were significantly higher in both aqueous tear deficiency and conjunctivochalasis compared with control. Among all subjects, blink rate positively correlated with ocular surface staining and irritation and inversely correlated with TBUT. Conclusion Amongst conditions causing tear dysfunction, reduced corneal sensitivity is associated with greater irritation, tear instability, ocular surface disease and blink rate. Rapid blinking is associated with worse ocular surface disease and tear stability.

Objective: To describe reoperations in the operating room for complications encountered within 90 days after glaucoma surgery at a single institution over a 2-year period. Design: Retrospective case series. Subjects: Adult patients who have undergone glaucoma surgery including a tube shunt, trabeculectomy with mitomycin C, trabectome, or transcleral cyclophotocoagulation from June 1, 2015 to August 30, 2017 at a single institution. Methods: These patients were then examined for postoperative complications that required reoperations within the first 90 days including revision of the tube shunt, revision of the trabeculectomy, drainage of the choroidal, or placement of a tube shunt. Main Outcome Measures: Percentage of reoperations for complications within the first 90 days after glaucoma surgery and surgical indications for these reoperations. Results: A total of 622 glaucoma procedures were performed on 600 eyes in 525 patients over a 2-year period from June 1, 2015 to June 30, 2017 by 4 glaucoma surgeons at a single institution. Of these, 275 (44%) were trabeculectomy with mitomycin C, 253 (41%) were the placement of a tube shunt, 33 (5%) were cyclophotocoagulation, and 61 (10%) were trabectome procedures. Postoperative complications requiring reoperations within 90 days developed in 15 patients (2.4%) overall including 7 patients (2.5%) in the trabeculectomy with mitomycin C group and 8 patients (3.1%) in the tube shunt group. Five patients developed bleb leaks, 3 patients developed serous choroidal effusions, 3 patients had tube exposure, 1 patient had tube retraction, 1 patient had persistent iritis from iris touching the tube, and 1 had encapsulation around the tube. The rate of reoperation for complications was similar between the tube group and the trabeculectomy group (P=0.67, χ 2 test). There were no complications requiring reoperations in 90 days for transcleral cyclophotocoagulation or trabectome. Conclusions: Early postoperative complications requiring reoperations within the first 90 days after glaucoma surgery were low and comparable with previous studies. Common indications for reoperation within 90 days include wound leak and tube shunt-related issues.

A 51-year-old man with rheumatoid arthritis and diabetes mellitus presented with new onset left-sided hemiparesis, left-sided neglect, and left-sided incongruous, denser inferiorly, homonymous hemianopsia. Magnetic resonance image of the brain showed prominent swelling of the right frontal, parietal, and occipital lobes greater than on the left with significant change in the fluid-attenuated inversion recovery signal in the gray matter. Perinuclear antineutrophil cytoplasmic antibodies titers were elevated, and skin biopsy demonstrating leukocytoclastic vasculitis. He showed marked clinical and radiographic improvement in association with recovery of vascular abnormalities after the initiation of prednisone, pulse therapy with methylprednisolone, and methotrexate. Clinicians should be aware of the possibility of neuro-ophthalmic manifestations of rheumatoid arthritis, including rheumatoid arthritis-related vasculitis causing homonymous hemianopsia.