Nucleic acid detection aboard the International Space Station by colorimetric loop-mediated isothermal amplification (LAMP).

Human spaceflight endeavors present an opportunity to expand our presence beyond Earth. To this end, it is crucial to understand and diagnose effects of long-term space travel on the human body. Developing tools for targeted, on-site detection of specific DNA sequences will allow us to establish research and diagnostics platforms that will benefit space programs. We describe a simple DNA diagnostic method that utilizes colorimetric loop-mediated isothermal amplification (LAMP) to enable detection of a repetitive telomeric DNA sequence in as little as 30 minutes. A proof of concept assay for this method was carried out using existing hardware on the International Space Station and the results were read instantly by an astronaut through a simple color change of the reaction mixture. LAMP offers a novel platform for on-orbit DNA-based diagnostics that can be deployed on the International Space Station and to the broader benefit of space programs.

Erratum: Author Correction: Successful amplification of DNA aboard the International Space Station.

[This corrects the article DOI: 10.1038/s41526-017-0033-9.].

Successful amplification of DNA aboard the International Space Station.

As the range and duration of human ventures into space increase, it becomes imperative that we understand the effects of the cosmic environment on astronaut health. Molecular technologies now widely used in research and medicine will need to become available in space to ensure appropriate care of astronauts. The polymerase chain reaction (PCR) is the gold standard for DNA analysis, yet its potential for use on-orbit remains under-explored. We describe DNA amplification aboard the International Space Station (ISS) through the use of a miniaturized miniPCR system. Target sequences in plasmid, zebrafish genomic DNA, and bisulfite-treated DNA were successfully amplified under a variety of conditions. Methylation-specific primers differentially amplified bisulfite-treated samples as would be expected under standard laboratory conditions. Our findings establish proof of concept for targeted detection of DNA sequences during spaceflight and lay a foundation for future uses ranging from environmental monitoring to on-orbit diagnostics.

Postoperative Hemorrhagic Occlusive Retinal Vasculitis: Expanding the Clinical Spectrum and Possible Association with Vancomycin.

PURPOSE: To describe a syndrome of hemorrhagic occlusive retinal vasculitis (HORV) that developed after seemingly uncomplicated cataract surgery. DESIGN: Retrospective case series. SUBJECTS: Eleven eyes of 6 patients from 6 different institutions. METHODS: Cases were identified after discussion among retina specialists. The findings on presentation, clinical course, and outcome of a series of 7 eyes of 4 patients were compared with a previous report of 4 eyes of 2 patients, and data from both series were combined for a comprehensive analysis. MAIN OUTCOME MEASURES: Historical data, examination findings, imaging results, systemic evaluation findings, treatment regimens, and visual outcomes. RESULTS: Eleven eyes of 6 patients underwent otherwise uncomplicated cataract surgery, receiving viscoelastic and prophylactic intracameral vancomycin during the procedure. Despite good initial vision on postoperative day 1, between 1 to 14 days after surgery, all eyes demonstrated painless vision loss resulting from HORV. Extensive ocular and systemic evaluations were unrevealing in all patients. All patients were treated with aggressive systemic and topical corticosteroids. Additional treatments included systemic antiviral medication in 4 patients, intravitreal antibiotics in 4 eyes, and pars plana vitrectomy in 4 eyes. Skin testing for vancomycin sensitivity showed negative results in 3 patients and was not performed in the others. Neovascular glaucoma developed in 7 eyes, and all eyes received intravitreal anti-vascular endothelial growth factor (VEGF) injection, panretinal photocoagulation, or both for retinal ischemia. Final visual acuity was less than 20/100 in 8 of 11 eyes. CONCLUSIONS: Postoperative HORV is an exceedingly rare and potentially devastating condition that can occur after otherwise uncomplicated cataract surgery. Although the precise cause remains unknown, this disease may represent a delayed immune reaction similar to vancomycin-induced leukocytoclastic vasculitis. Despite treatment with high-dose corticosteroids, antiviral medication, and early vitrectomy in many patients, visual outcomes typically were poor in this series. Early intervention with intravitreal anti-VEGF medication and panretinal photocoagulation may help to prevent additional vision loss resulting from neovascular glaucoma.

Outcomes of cataract surgery in graft-versus-host disease.

PURPOSE: To study the outcomes of cataract surgery in patients with graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation (HSCT). METHODS: Retrospective review of 72 eyes of 41 patients (age, 17-69 years at the time of surgery) with chronic GVHD after HSCT, who underwent cataract surgery between 2008 and 2012 at the Department of Ophthalmology and Visual Sciences, W. K. Kellogg Eye Center, University of Michigan. Ophthalmic data collected included best-corrected visual acuity (BCVA), responses to Ocular Surface Disease Index (OSDI) questionnaire, dry eye severity, and postoperative complications. RESULTS: BCVA improved from 20/49 to 20/25 (P < 0.0001) after surgery. Eight patients (20%) had pretransplantation total body irradiation and 39 patients (95%) received systemic corticosteroids for the treatment of GVHD. Postoperative complications included cystoid macular edema (4 eyes), corneal ulceration with perforation (2 eyes: 1 infected and 1 sterile), and band keratopathy (1 eye). After surgery, subjective OSDI responses and dry eye disease (DED) did not change significantly from before cataract surgery, although OSDI showed a trend toward worsening. CONCLUSIONS: With careful monitoring and management of DED and concurrent ocular surface disease, cataract surgery generally has good visual outcomes in patients with GVHD. However, aggravation of the preexisting ocular surface disease is frequent, and despite meticulous postoperative maintenance therapy, vision-threatening complications may occur.

Outcomes of cataract surgery in eyes with previous herpes zoster ophthalmicus.

PURPOSE: To report the outcomes of cataract surgery in eyes with previous herpes zoster ophthalmicus (HZO). SETTING: Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, USA. DESIGN: Retrospective case series. METHODS: Eyes with a history of HZO that had phacoemulsification and intraocular lens implantation were reviewed. The information analyzed included the ophthalmologic history, visual acuity, preoperative and postoperative adjunct treatments, and complications. Analysis of the mean corrected distance visual acuity (CDVA) at 1 month, 1 year, and the last follow-up was performed. RESULTS: Twenty-four eyes were evaluated. The mean CDVA improved from 20/112 (0.75 logMAR ± 0.63 [SD]) preoperatively to 20/53 (0.42 ± 0.56 logMAR) 1 month postoperatively (P = .007) and 20/44 (0.34 ± 0.55 logMAR) at 1 year (P = .052) but decreased to 20/71 (0.55 ± 0.72 logMAR) by last follow-up (P = .605 versus preoperative CDVA). Eleven patients (45.8%) had recurrent keratouveitis after the first episode, 5 before cataract surgery and 6 after cataract surgery. Three had penetrating keratoplasty for worsening corneal opacification. Two patients had tractional retinal detachment from chronic uveitis and required vitrectomy and retinal repair. CONCLUSIONS: Visual recovery after cataract surgery in HZO might be compromised by chronic factors such as ocular surface disease and keratouveitis. Despite long quiescent waiting periods before surgery and aggressive preoperative and postoperative maintenance therapy, visual improvement might be hindered by the inherent pathology associated with HZO. Nevertheless, with careful patient selection, reasonable visual improvement can be achieved. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.