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Smartphone-based retinal photography is a promising method for increasing accessibility of retinal screening in the primary care and community settings. Recent work has focused on validating its use in detection of diabetic retinopathy. However, retinal imaging can be technically challenging and additional work is needed to improve ease of retinal imaging in the primary care setting. We therefore performed usability testing of a smartphone-based retinal camera, RetinaScope, among medical assistants in primary care who had never performed retinal imaging. A total of 24 medical assistants performed first-time imaging in a total of five rounds of testing, and iterative improvements to the device were made between test rounds based on the results. The time to acquire a single ~50 degree image of the posterior pole of a model eye decreased from 283 ± 60 seconds to 34 ± 17 seconds (p < 0.01) for first-time users. The time to acquire 5 overlapping images of the retina decreased from 325 ± 60 seconds to 118 ± 26 seconds (p = 0.02) for first-time users. Testing in the human eye demonstrated that a single wide-view retinal image could be captured in 65 ± 7 seconds and 5 overlapping images in 229 ± 114 seconds. Users reported high Systems Usability Scores of 86 ± 13 throughout the rounds, reflecting a high level of comfort in first-time operation of the device. Our study demonstrates that smartphone-based retinal photography has the potential to be quickly adopted among medical assistants in the primary care setting.

PurposeHigh-quality, wide-field retinal imaging is a valuable method for screening preventable, vision-threatening diseases of the retina. Smartphone-based retinal cameras hold promise for increasing access to retinal imaging, but variable image quality and restricted field of view can limit their utility. We developed and clinically tested a smartphone-based system that addresses these challenges with automation-assisted imaging.MethodsThe system was designed to improve smartphone retinal imaging by combining automated fixation guidance, photomontage, and multicolored illumination with optimized optics, user-tested ergonomics, and touch-screen interface. System performance was evaluated from images of ophthalmic patients taken by nonophthalmic personnel. Two masked ophthalmologists evaluated images for abnormalities and disease severity.ResultsThe system automatically generated 100° retinal photomontages from five overlapping images in under 1 minute at full resolution (52.3 pixels per retinal degree) fully on-phone, revealing numerous retinal abnormalities. Feasibility of the system for diabetic retinopathy (DR) screening using the retinal photomontages was performed in 71 diabetics by masked graders. DR grade matched perfectly with dilated clinical examination in 55.1% of eyes and within 1 severity level for 85.2% of eyes. For referral-warranted DR, average sensitivity was 93.3% and specificity 56.8%.ConclusionsAutomation-assisted imaging produced high-quality, wide-field retinal images that demonstrate the potential of smartphone-based retinal cameras to be used for retinal disease screening.Translational relevanceEnhancement of smartphone-based retinal imaging through automation and software intelligence holds great promise for increasing the accessibility of retinal screening.

Background: Even among HIV-infected patients who fully suppress plasma HIV RNA replication on antiretroviral therapy, genetic (e.g. CCL3L1 copy number), viral (e.g. tropism) and environmental (e.g. chronic exposure to microbial antigens) factors influence CD4 recovery. These factors differ markedly around the world and therefore the expected CD4 recovery during HIV RNA suppression may differ globally. Methods: We evaluated HIV-infected adults from North America, West Africa, East Africa, Southern Africa and Asia starting non-nucleoside reverse transcriptase inhibitorbased regimens containing efavirenz or nevirapine, who achieved at least one HIV RNA level < 500/μl in the first year of therapy and observed CD4 changes during HIV RNA suppression. We used a piecewise linear regression to estimate the influence of region of residence on CD4 recovery, adjusting for socio-demographic and clinical characteristics. We observed 28 217 patients from 105 cohorts over 37 825 person-years. Results: After adjustment, patients from East Africa showed diminished CD4 recovery as compared with other regions. Three years after antiretroviral therapy initiation, the mean CD4 count for a prototypical patient with a pre-therapy CD4 count of 150/μl was 529/μl [95% confidence interval (CI): 517-541] in North America, 494/μl (95% CI: 429-559) in West Africa, 515/μl (95% CI: 508-522) in Southern Africa, 503/μl (95% CI: 478-528) in Asia and 437/μl (95% CI: 425-449) in East Africa. Conclusions: CD4 recovery during HIV RNA suppression is diminished in East Africa as compared with other regions of the world, and observed differences are large enough to potentially influence clinical outcomes. Epidemiological analyses on a global scale can identify macroscopic effects unobservable at the clinical, national or individual regional level.

Inhibition of DAF-2 (insulin-like growth factor 1 [IGF-1] receptor) or RSKS-1 (S6K), key molecules in the insulin/IGF-1 signaling (IIS) and target of rapamycin (TOR) pathways, respectively, extend lifespan in Caenorhabditis elegans. However, it has not been clear how and in which tissues they interact with each other to modulate longevity. Here, we demonstrate that a combination of mutations in daf-2 and rsks-1 produces a nearly 5-fold increase in longevity that is much greater than the sum of single mutations. This synergistic lifespan extension requires positive feedback regulation of DAF-16 (FOXO) via the AMP-activated protein kinase (AMPK) complex. Furthermore, we identify germline as the key tissue for this synergistic longevity. Moreover, germline-specific inhibition of rsks-1 activates DAF-16 in the intestine. Together, our findings highlight the importance of the germline in the significantly increased longevity produced by daf-2 rsks-1, which has important implications for interactions between the two major conserved longevity pathways in more complex organisms.

Bicontinuous cubic (Q) lyotropic liquid crystal (LLC)‐derived polymer networks possess periodic, uniform‐size, 3D‐interconnected nanopores that make them highly desirable organic materials for selective molecular separation and uptake applications. To date, there are no reported examples of a Q‐phase network with additional functional properties, such as catalytic reactivity, response to external stimuli, or gated transport, that would expand the usefulness of this class of porous materials. Here, a functionalized gyroid‐type Q polymer network material that can be used for potential gated transport or adaptive uptake applications is presented. This material contains a novel spiropyran‐containing dopant monomer that upon blending and cross‐linking with a gyroid‐forming LLC monomer, yields a gyroid polymer material that retains its phase architecture while reversibly responding to changes in external solution and vapor pH. Studies also demonstrate that this system is capable of strongly binding to aq. Pb2+ ions when activated by UV light, allowing it to function as a potential colorimetric sorbent or gated‐response material. [ABSTRACT FROM AUTHOR]