CENTRAL RETINAL VEIN OCCLUSION ASSOCIATED WITH USE OF AMYL NITRITE "POPPERS".

PURPOSE: To report a case of central retinal vein occlusion in a young patient after the use of amyl nitrate "poppers." METHODS: Description of the patient's clinical history, ophthalmic examination, retinal imaging, and treatment. RESULTS: A 38-year-old man presented with a central retinal vein occlusion in his right eye after inhaling amyl nitrite "poppers." There appeared to be a definitive temporal association between poppers use and both the onset of the vein occlusion and the patient's visual scotomata, which recurred immediately after drug use multiple times. Optical coherence tomography displayed cystic macular edema, which was treated with intravitreal bevacizumab. The patient's hypercoagulable laboratory workup was negative. CONCLUSION: This is the first report of a central retinal vein occlusion associated with poppers inhalation. A high index of suspicion for poppers use should be maintained in young patients who present with retinal vein occlusion, particularly in homosexual patients with a normal laboratory workup that fails to reveal a hypercoagulable etiology.

Organic carbon accumulation in British saltmarshes.

Saltmarshes are a crucial component of the coastal carbon (C) system and provide a natural climate regulation service through the accumulation and long-term storage of organic carbon (OC) in their soils. These coastal ecosystems are under growing pressure from a changing climate and increasing anthropogenic disturbance. To manage and protect these ecosystems for C and to allow their inclusion in emissions and natural-capital accounting, as well as carbon markets, accurate and reliable estimates of OC accumulation are required. However, globally, such data are rare or of varying quality. Here, we quantify sedimentation rates and OC densities for 21 saltmarshes in Great Britain (GB). We estimate that, on average, saltmarshes accumulate OC at a rate of 110.88 ± 43.12 g C m-2 yr-1. This is considerably less than widely applied global saltmarsh averages. It is therefore highly likely that the contribution of northern European saltmarshes to global saltmarsh OC accumulation has been significantly overestimated. Taking account of the climatic, geomorphological, oceanographic, and ecological characteristics of all GB saltmarshes and the areal extent of different saltmarsh zones, we estimate that the 451.65 km2 of GB saltmarsh accumulates 46,563 ± 4353 t of OC annually. These low OC accumulation rates underline the importance of the 5.20 ± 0.65 million tonnes of OC already stored in these vulnerable coastal ecosystems. Going forward the protection and preservation of the existing stores of OC in GB saltmarshes must be a priority for the UK as this will provide climate benefits through avoided emissions several times more significant than the annual accumulation of OC in these ecosystems.

Two-year outcomes of the ranibizumab for edema of the mAcula in diabetes (READ-2) study.

OBJECTIVES: To determine the long-term effects of ranibizumab (RBZ) in patients with diabetic macular edema (DME). DESIGN: Prospective, randomized, interventional, multicenter clinical trial. PARTICIPANTS: One hundred twenty-six patients with DME. METHODS: Subjects were randomized 1:1:1 to receive 0.5 mg RBZ at baseline and months 1, 3, and 5 (group 1), focal or grid laser photocoagulation at baseline and month 3 if needed (group 2), or a combination of 0.5 mg RBZ and focal or grid laser at baseline and month 3 (group 3). Starting at month 6, if retreatment criteria were met, all subjects could be treated with RBZ. MAIN OUTCOME MEASURES: The mean change from baseline in best-corrected visual acuity (BCVA) at month 24. RESULTS: After the primary end point at month 6, most patients in all groups were treated only with RBZ, and the mean number of injections was 5.3, 4.4, and 2.9 during the 18-month follow-up period in groups 1, 2, and 3, respectively. For the 33 patients in group 1, 34 patients in group 2, and 34 patients in group 3 who remained in the study through 24 months, the mean improvement in BCVA was 7.4, 0.5, and 3.8 letters at the 6-month primary end point, compared with 7.7, 5.1, and 6.8 letters at month 24, and the percentage of patients who gained 3 lines or more of BCVA was 21, 0, and 6 at month 6, compared with 24, 18, and 26 at month 24. The percentage of patients with 20/40 or better Snellen equivalent at month 24 was 45% in group 1, 44% in group 2, and 35% in group 3. Mean foveal thickness (FTH), defined as center subfield thickness, at month 24 was 340 µm, 286 µm, and 258 µm for groups 1, 2, and 3, respectively, and the percentage of patients with center subfield thickness of 250 µm or less was 36%, 47%, and 68%, respectively. CONCLUSIONS: Intraocular injections of RBZ provided benefit for patients with DME for at least 2 years, and when combined with focal or grid laser treatments, the amount of residual edema was reduced, as were the frequency of injections needed to control edema. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Electrical Control of Escherichia coli Growth Measured with Simultaneous Modulation and Imaging.

Background: The use of electricity to mediate bacterial growth is unique in providing spatial control, but requires a more detailed understanding. Methods: We use two gold wires on a glass coverslip with an overlayer of agar to image Escherichia coli cells with brightfield and fluorescence microscopy while simultaneously applying a voltage. Cells outside of the wires provide a control population to measure cell growth as a function of voltage, rather than any difference in culture conditions or growth phase. Results: An applied voltage suppresses the fraction of E. coli undergoing elongation and division with recovery to control values when the voltage is removed. Depolarization is observed over the same voltage range suggesting a membrane potential-mediated response. Conclusions: Our experiments identify and use subcytotoxic voltages to measure differences in the fraction of E. coli cells elongating and dividing as a function of applied voltage. It is hoped that this research will inform the developing field of bacterial electrophysiology.