No abstract

Molecular probes with zinc(II)-(2,2'-dipicolylamine) coordination complexes associate with oxyanions in aqueous solution and target biomembranes that contain anionic phospholipids. This study examines a new series of coordination complexes with 2,6-bis(zinc(II)-dipicolylamine) phenoxide as the molecular recognition unit. Two lipophilic analogues are observed to partition into the membranes of zwitterionic and anionic vesicles and induce the transport of phospholipids and hydrophilic anions (carboxyfluorescein). These lipophilic zinc complexes are moderately toxic to mammalian cells. A more hydrophilic analogue does not exhibit mammalian cell toxicity (LD 50 >50 µg/mL), but it is highly active against the Gram-positive bacteria Staphylococcus aureus (MIC of 1 µg/mL). Furthermore, it is active against clinically important S. aureus strains that are resistant to various antibiotics including vancomycin and oxacillin. The antibiotic action is attributed to its ability to depolarize the bacterial cell membrane. The intense bacterial staining exhibited by a fluorescent conjugate suggests that this family of zinc coordination complexes can be used as molecular probes for the detection and imaging of bacteria.

As the ophthalmology accreditation system undergoes major changes, training programs must evaluate residents in the 6 core competencies, including appropriately communicating bad news. Although the literature is replete with recommendations for breaking bad news across various non-ophthalmology specialties, no formal training programs exist for ophthalmology. There are many valuable lessons to be learned from our non-ophthalmology colleagues regarding this important skill. We examine the historic basis for breaking bad news, explores current recommendations among other specialties, and then evaluate a pilot study to teach breaking bad news to ophthalmology residents. The results of this study are limited by a small number of residents at a single academic center. Future studies from multiple training programs should be conducted to further evaluate the need and efficacy of formal communication skills training in this area, as well as the generalizability of our pilot training program. If validated, this work could serve as a template for future ophthalmology resident training and evaluation in this core competency.

Posterior keratoconus (PKC) is a rare, typically non-inflammatory condition that is characterised by an abnormal posterior corneal curvature, which may be accompanied by overlying stromal opacification. It is usually congenital and can be associated with other ocular and systemic abnormalities. PKC remains a clinical diagnosis, although imaging techniques including ultrasound biomicroscopy and anterior segment optical coherence tomography may be useful tools for confirmation and classification. Genetic studies should be considered, although no specific genetic defects have been identified thus far. As a potential cause of amblyopia, early diagnosis and management are crucial in maximising visual potential. Occasionally, management considerations may also include surgical intervention, such as corneal transplantation. Intraocular lens power calculation at the time of cataract surgery requires special consideration. Here, we review the present literature on PKC and consider future directions in the management of this rare entity.