Browsing by Subject "insulin"

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    Interview with Walter Gilbert by Molly Nicholson and Robert Cook-Deegan
    (2005-08-01) Gilbert, Walter
    Walter Gilbert is a Nobel Laureate. He received the 1980 Nobel Prize in Chemistry for his work on sequencing DNA. He also joined the race to sequence the insulin gene and was one of the early leaders in the biotechnology industry.
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    ItemOpen Access
    L1 arrest, daf-16/FoxO and nonautonomous control of post-embryonic development.
    (Worm, 2016-04) Kaplan, Rebecca EW; Baugh, L Ryan
    Post-embryonic development is governed by nutrient availability. L1 arrest, dauer formation and aging illustrate how starvation, anticipation of starvation and caloric restriction have profound influence on C. elegans development, respectively. Insulin-like signaling through the Forkhead box O transcription factor daf-16/FoxO regulates each of these processes. We recently reported that ins-4, ins-6 and daf-28 promote L1 development from the intestine and chemosensory neurons, similar to their role in dauer development. daf-16 functions cell-nonautonomously in regulation of L1 arrest, dauer development and aging. Discrepancies in daf-16 sites of action have been reported in each context, but the consensus implicates epidermis, intestine and nervous system. We suggest technical limitations of the experimental approach responsible for discrepant results. Steroid hormone signaling through daf-12/NHR is known to function downstream of daf-16 in control of dauer development, but signaling pathways mediating cell-nonautonomous effects of daf-16 in aging and L1 arrest had not been identified. We recently showed that daf-16 promotes L1 arrest by inhibiting daf-12/NHR and dbl-1/TGF-β Sma/Mab signaling, two pathways that promote L1 development in fed larvae. We will review these results on L1 arrest and speculate on why there are so many signals and signaling centers regulating post-embryonic development.
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    ItemOpen Access
    The effect of select systemic medications on outcomes in diabetics with central retinal vein occlusion.
    (Therapeutic advances in ophthalmology, 2022-01) Simmons, Kirsten; Singh, Pali; Borkar, Durga S; Birnbaum, Faith; Thomas, Akshay S; Fekrat, Sharon

    Background

    Diabetes mellitus is a risk factor for central retinal vein occlusion (CRVO); however, it is unclear whether certain commonly used medications among diabetics or glycemic control impact visual outcomes in diabetic eyes with CRVO.

    Purpose

    To evaluate the effect of select systemic medications and glycemic control on presenting features, treatment burden, and outcomes in patients with diabetes who develop a central retinal vein occlusion (CRVO).

    Methods

    Retrospective longitudinal cohort study at a single tertiary academic referral center from 2009-2017 investigating eyes of patients being treated for diabetes mellitus at CRVO onset. Eyes with a prior history of anti-vascular endothelial growth factor (anti-VEGF) therapy or laser treatment within the year prior to CRVO onset were excluded. Main outcomes and measures were visual acuity (VA), central subfield thickness (CST), cystoid macular edema (CME), and number of intravitreal injections and laser treatment throughout follow-up.

    Results

    We identified 138 eyes of 138 participants who were diabetic at CRVO onset. Of these, 49% had an ischemic CRVO. Median follow-up time was 25.5 months. Fifty-five eyes (40%) had a HbA1c within 6 months of CRVO presentation. HbA1c was positively correlated with both presenting CST (p = 0.04) and presence of CME (p < 0.01). In all 138 eyes, mean presenting VA was 20/246, and mean final VA was 20/364. Better-presenting VA was significantly associated with aspirin 325 mg use (p = 0.04). Lower CST at presentation was significantly associated with metformin use (p = 0.02). Sitagliptin use at CRVO onset was associated with a lower prevalence of CME at final follow-up (p < 0.01). Lower final CST was significantly associated with glipizide use at CRVO onset (p = 0.01). There were no significant associations between systemic medications or HbA1c and treatment burden or final VA (p > 0.05).

    Conclusion

    Although aspirin 325 mg, metformin, sitagliptin, and glipizide were associated with better-presenting VA, lower-presenting CST, lower prevalence of macular edema at final visit, and lower final CST, respectively, none of these systemic agents or glycemic control were associated with decreased treatment burden or improved visual outcomes in diabetics with CRVO.