Trends in contact lens microbial keratitis 1999 to 2015: a retrospective clinical review.

IMPORTANCE: Contact lens microbial keratitis (CLMK) is the most common cause of microbial keratitis in our community. BACKGROUND: Define the trend in rate of CLMK and define patient demographics/culture results that may have a predictive value in patients with CLMK. DESIGN: Retrospective review of clinical records of patients with MK. PARTICIPANTS: All patients with positive corneal scraping between 1999 and 2015 at the Princess Alexandra Hospital, Brisbane, Queensland identified through local microbiology database. METHODS: Trend in CLMK tested with chi-squared test of peak 3 years vs other years and Poisson regression of interrupted time series. Patient characteristics predictive of CLMK were defined by creating a polynomial regression model by stepwise variable selection. MAIN OUTCOME MEASURES: Yearly rate of CLMK. RESULTS: Records of 895 episodes of MK were included. The most common: risk factor was contact lens wear (324, 36.2%), isolated organism was Pseudomonas aeruginosa (P. aeruginosa 181, 55.9%) and treatment was monotherapy with a fluoroquinolone 172, 53%). CLMK was most common between 2009 and 2011 (49.5% vs other years 32%, P < 0.001). Poisson regression of the interrupted time series showed there was a significant decrease in the rate over time after 2010 (P < 0.001). Independent factors predictive of CLMK in multivariate regression were young age (15-49 years) and corneal culture positive for P. aeruginosa CONCLUSIONS AND RELEVANCE: The rate of CLMK in our community ranged between 32% and 50% and the rate of disease appears to have peaked during 2009 to 2011 and subsequently declined.

High-Dose Steroid Treatment of Bacterial Keratitis.

PURPOSE: To describe the usage patterns of steroids in bacterial keratitis and to analyze the effect of steroids on patients' visual outcomes. METHODS: This was a single-center retrospective review of patients with culture-positive bacterial keratitis treated between 1999 and 2015 at Princess Alexandra Hospital (Brisbane, Australia). Patients with culture-positive bacterial keratitis were identified through the Queensland Pathology Database, and clinical information was gathered through a subsequent medical record review. High-dose steroid treatment was classified as 6 or more drops of a steroid a day started within 7 days of corneal scraping. The outcome of a patient's episode of keratitis was classified as good if their final visual acuity was 6/12 or better; poor if it was 6/60 or worse or required a corneal transplant, otherwise it was classified as average. Microbiological and clinical variables' association with outcomes was evaluated in univariate analyses. Variables significant at P < 0.1 were examined in a multivariate ordinal logistic regression analysis created with forward variable selection with forced inclusion of steroid treatment (high, regular, low dose, and none). RESULTS: A total of 328 patients were included from the 1002 reviewed charts. Of these patients, 164 (50.0%) were treated with steroids. Factors significantly associated with outcomes in the multivariate model were high-dose steroid treatment, visual acuity on presentation, age group, cause of keratitis, infiltrate size, and location. The odds ratio of better outcomes with high-dose steroids was 5.49 (confidence interval, 1.6-19.0, P = 0.007). CONCLUSIONS: High-dose steroid treatment is significantly associated with better visual outcomes in patients with culture-positive bacterial keratitis in this case series.

Three cases of ocular syphilis and the resurgence of the disease in Queensland.

The past few years has seen a resurgence of syphilis. It is predominantly associated within men who have sex with men and also within heterosexual Indigenous Australians. Possessing the ability to mimic a variety of ocular diseases, it typically manifests as uveitis, although it can affect any structure within the eye. Thus, a high degree of clinical suspicion by ophthalmologists is required to prevent disease progression and ocular morbidity. Patients require prolonged antibiotic treatment with intravenous benzylpenicillin and outpatient monitoring to successfully resolve the infection. We describe a case series of ocular syphilis presentations in Queensland, Australia.

Multidrug-resistant Fusarium keratitis: diagnosis and treatment considerations.

Mycotic keratitis is an ocular infective process derived from any fungal species capable of corneal invasion. Despite its rarity in developed countries, its challenging and elusive diagnosis may result in keratoplasty or enucleation following failed medical management. Filamentous fungi such as Fusarium are often implicated in mycotic keratitis. Bearing greater morbidity than its bacterial counterpart, mycotic keratitis requires early clinical suspicion and initiation of antifungal therapy to prevent devastating consequences. We describe a case of multidrug-resistant mycotic keratitis in a 46-year-old man who continued to decline despite maximal therapy and therapeutic keratoplasty. Finally, enucleation was performed as a means of source control preventing dissemination of a likely untreatable fungal infection into the orbit. Multidrug-resistant Fusarium is rare, and may progress to endophthalmitis. We discuss potential management options which may enhance diagnosis and outcome in this condition.

Controlled presentation of recombinant proteins via a zinc-binding peptide-linker in two and three dimensional formats.

The presentation of proteins on surfaces is fundamental to numerous cell culture and tissue engineering applications. While a number of physisorption and cross-linking methods exist to facilitate this process, few avoid denaturation of proteins or allow control over protein orientation, both of which are critical to the functionality of many signal proteins and ligands. Often recombinant protein sequences include a poly-histidine tag to facilitate purification. We utilize this sequence to anchor proteins to biosurfaces via a peptide bonded to the surface which conjugates with the poly-histidine tag in the presence of zinc rather than nickel, which is more traditionally used to conjugate poly-histidine tags to surfaces. We demonstrate that this strategy enables the display of proteins on 2D and 3D surfaces without compromising protein function through direct cross-linking or physisorption.

An architectural role for a nuclear noncoding RNA: NEAT1 RNA is essential for the structure of paraspeckles.

NEAT1 RNA, a highly abundant 4 kb ncRNA, is retained in nuclei in approximately 10 to 20 large foci that we show are completely coincident with paraspeckles, nuclear domains implicated in mRNA nuclear retention. Depletion of NEAT1 RNA via RNAi eradicates paraspeckles, suggesting that it controls sequestration of the paraspeckle proteins PSP1 and p54, factors linked to A-I editing. Unlike overexpression of PSP1, NEAT1 overexpression increases paraspeckle number, and paraspeckles emanate exclusively from the NEAT1 transcription site. The PSP-1 RNA binding domain is required for its colocalization with NEAT1 RNA in paraspeckles, and biochemical analyses support that NEAT1 RNA binds with paraspeckle proteins. Unlike other nuclear-retained RNAs, NEAT1 RNA is not A-I edited, consistent with a structural role in paraspeckles. Collectively, results demonstrate that NEAT1 functions as an essential structural determinant of paraspeckles, providing a precedent for a ncRNA as the foundation of a nuclear domain.

hnRNP A2, a potential ssDNA/RNA molecular adapter at the telomere.

The heterogeneous nuclear ribonucleoprotein (hnRNP) A2 is a multi-tasking protein that acts in the cytoplasm and nucleus. We have explored the possibility that this protein is associated with telomeres and participates in their maintenance. Rat brain hnRNP A2 was shown to have two nucleic acid binding sites. In the presence of heparin one site binds single-stranded oligodeoxyribonucleotides irrespective of sequence but not the corresponding oligoribonucleotides. Both the hnRNP A2-binding cis-acting element for the cytoplasmic RNA trafficking element, A2RE, and the ssDNA telomere repeat match a consensus sequence for binding to a second sequence-specific site identified by mutational analysis. hnRNP A2 protected the telomeric repeat sequence, but not the complementary sequence, against DNase digestion: the glycine-rich domain was found to be necessary, but not sufficient, for protection. The N-terminal RRM (RNA recognition motif) and tandem RRMs of hnRNP A2 also bind the single-stranded, template-containing segment of telomerase RNA. hnRNP A2 colocalizes with telomeric chromatin in the subset of PML bodies that are a hallmark of ALT cells, reinforcing the evidence for hnRNPs having a role in telomere maintenance. Our results support a model in which hnRNP A2 acts as a molecular adapter between single-stranded telomeric repeats, or telomerase RNA, and another segment of ssDNA.