Purpose: The retinal blood vessels provide a unique way to directly examine the human microvasculature, which is frequently damaged in individuals with diabetes. Previous studies have demonstrated that retinal flickering light-induced vasodilation and hyperoxia-induced vasoconstriction may operate by enhancing or reducing similar vasoregulatory factor(s), but a comparison between these two provocative stimuli in individuals with diabetes has not been studied. The purpose of the study was to examine the association between retinal flickering light-induced vasodilation and retinal hyperoxia-induced vasoconstriction in type 2 diabetic subjects and in healthy controls.
Methods: Twenty men and women with type 2 diabetes and 10 men and women without diabetes between 21 and 75 years of age were recruited. Changes in retinal artery and vein diameters to flickering light and during hyperoxia (100% oxygen) stimuli were measured on the same visit using a noninvasive retinal imaging device (Dynamic Vessel Analyzer, Imedos Inc., Germany).
Results: Compared with controls, diabetic subjects had impaired arterial vasodilator and vasoconstrictor responses to both flickering light and hyperoxia, respectively (both p<0.001). Merging both groups, an inverse correlation (r=-0.56; p=0.003) between the retinal artery's responses to flickering light-induced vasodilation and hyperoxia-induced vasoconstriction was demonstrated independent of glucose or insulin levels.
Conclusion: This suggests that both responses are attenuated to a similar degree in diabetic subjects and that the attenuation to both stimuli can be observed in retinal arteries and veins. This would suggest that similar vasoregulatory factor(s) might in part help to explain the retinal diameter responses between the two stimuli. One suggested common vasoregulator of vascular tone is nitric oxide; however, other factor(s) may be involved, which contribute to this association and require further research.
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http://dx.doi.org/10.1111/j.1755-3768.2012.02445.x | DOI Listing |
Ann Intern Med
January 2025
Department of Research and Evaluation, Kaiser Permanente Southern California, Pasadena, California (A.B., K.J.C., A.A.K.).
Background: Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) differ in their effects on body weight and risk for reoperation. However, it is unclear whether long-term health expenditures differ by procedure type in patients with diabetes.
Objective: To compare health expenditures 3 years before and 5.
PLoS One
January 2025
Department of Laboratory Medicine, People's Hospital of Shenzhen Baoan District, Shenzhen, P. R. China.
Objectives: This case-control study aims to clarify the impact of single nucleotide polymorphisms (SNPs) within the P2X7 gene on susceptibility to type 2 diabetes mellitus (T2DM) and to evaluate their association with diabetic complications.
Methods: This study is comprised with 200 T2DM cases and 200 healthy controls. Seven candidate SNP loci were screened, and TaqMan-MGB real-time PCR technology was used to determine the polymorphic variants of P2X7.
PLoS One
January 2025
Institute of Visual Informatics, The National University of Malaysia (UKM), Bangi, Malaysia.
Patients with type 1 diabetes and their physicians have long desired a fully closed-loop artificial pancreas (AP) system that can alleviate the burden of blood glucose regulation. Although deep reinforcement learning (DRL) methods theoretically enable adaptive insulin dosing control, they face numerous challenges, including safety and training efficiency, which have hindered their clinical application. This paper proposes a safe and efficient adaptive insulin delivery controller based on DRL.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
State Key Laboratory of Advanced Drug Delivery and Release Systems, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China.
Type 1 diabetes (T1D) is an autoimmune disorder in which pancreatic β-cells are destroyed by CD8 T cells. Anti-CD3 antibody effectively treats early-stage T1D when β-cell autoantibodies are detected but before symptoms appear. However, it impairs the immune system temporarily, exposing individuals to infection.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Nanjing University, School of Chemistry and Chemical Engineering, CHINA.
T cells play a pivotal role in the development of autoimmune diseases. To mitigate autoimmune inflammation without inducing global immunosuppression, it is crucial to selectively eliminate autoreactive T cell clones while preserving the normal T cell repertoire. In this study, we applied cellular proximity chemistry to develop a T-cell depletion method with clonal precision.
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