Purpose: To determine whether the human retinal oxygenation response (deltaPO2) to a hyperoxic provocation is abnormal in patients with type I diabetes.
Methods: Magnetic resonance imaging (MRI) was used to measure deltaPO2 during 100% oxygen breathing in patients with type I diabetes who had either no clinically detectable retinopathy (n = 5) or mild to moderate background diabetic retinopathy (BDR; n = 5) and in age-matched healthy control subjects (n = 7).
Results: Both the patients with diabetes and the control subjects exhibited a significant (P < 0.05) increase in the preretinal vitreous signal intensity on changing from room air breathing to oxygen inhalation (i.e., 5 minutes). However, only diabetic patients demonstrated significant (P < 0.05) increases in deltaPO2 between measurements made at 5 minutes of oxygen inhalation and measurements at longer durations of hyperoxia (15, 25, and 35 minutes). Furthermore, deltaPO2 was significantly (P < 0.05) greater in patients with diabetes than in control subjects, but there was no significant difference in deltaPO2 (P > 0.05) between patients with diabetes, with or without retinopathy. Age and deltaPO2 correlated significantly (P < 0.05) in control subjects but not in patients with diabetes. In control subjects, deltaPO2 was relatively uniform panretinally, whereas in the diabetic group, changes in oxygenation response were spatially inhomogeneous.
Conclusions: These results demonstrate, for the first time, that MRI deltaPO2 detects a significant supernormal retinal oxygenation response in patients with type I diabetes, even before the appearance of retinopathy. This study raises the possibility of using MRI measurements of deltaPO2 to monitor therapeutic efficacy in human trials.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1167/iovs.05-0833 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Essential Thrombocythemia: A Review.
JAMA
January 2025
CRIMM, Center Research and Innovation of Myeloproliferative Neoplasms, University of Florence, AOU Careggi, Florence, Italy.
Importance: Essential thrombocythemia, a clonal myeloproliferative neoplasm with excessive platelet production, is associated with an increased risk of thrombosis and bleeding. The annual incidence rate of essential thrombocythemia in the US is 1.5/100 000 persons.
View Article and Find Full Text PDFThe underlying mechanisms of the association of bone health with depression - an experimental study.
Mol Biol Rep
January 2025
Medical Sociology and Psychobiology, Department of Health and Physical Activity, University of Potsdam, 14469, Potsdam, Germany.
Background: Depression constitutes a risk factor for osteoporosis, but underlying molecular and cellular mechanisms are not fully understood. MiRNAs influence gene expression and are carried by extracellular vesicles (EV), affecting cell-cell communication.
Aims: (1) Identify the difference in miRNA expression between depressed patients and healthy controls; (2) Analyze associations of these miRNAs with bone turnover markers; (3) Analyze target genes of differentially regulated miRNAs and predict associated pathways regarding depression and bone metabolism.
EValuating Glucose ContrOL Using a Next-GeneraTION Automated Insulin Delivery Algorithm in Patients with Type 1 and Type 2 Diabetes: The EVOLUTION Study.
Diabetes Technol Ther
January 2025
Department of Paediatrics, University of Otago, Christchurch, New Zealand.
This study evaluated a next-generation automated insulin delivery (AID) algorithm for Omnipod in type 1 and type 2 diabetes across multiple phases: 14-day run-in with usual therapy, 48-h AID use in a hotel setting (type 1 only), and up to 6 weeks of outpatient AID use. Participants did, or did not, deliver manual boluses at alternating periods. Twelve adults with type 1 diabetes completed the hotel phase; 9 of those 12 plus 8 adults with type 2 diabetes completed the subsequent outpatient phase.
View Article and Find Full Text PDFThe triglyceride-glucose index as a surrogate measure to assess glycemic control in type 2 diabetes patients.
Ir J Med Sci
January 2025
Unidad de Investigación Biomédica, Delegación Durango, Instituto Mexicano del Seguro Social, Predio Canoas 100, Col. Los Angeles, Durango, 34077, México.
Background: It has been revealed that the potential utility of the triglycerides and glucose (TyG) index as an effective option for assessing glycemic control; however, evidence in this field is still scarce.
Aims: The goal of this study was to investigate the diagnostic accuracy of the TyG index, as an alternative option, to detect inadequate glycemic control in patients with type 2 diabetes (T2D).
Methods: Men and women between 30 and 60 years of age diagnosed with type 2 diabetes were included in a cross-sectional study.
The Changing pathogenesis of liver cancer in Hawaii over three decades.
Cancer Epidemiol Biomarkers Prev
January 2025
Queen's Medical Center, Honolulu, HI, United States.
Background: Worldwide trends support the increasing contribution of hepatic steatosis on the incidence of hepatocellular carcinoma (HCC). This study investigates if similar changes are seen in Hawaii, where the incidence of HCC is higher than most of the United States. Methods; This is a retrospective study of 1651 patients diagnosed with HCC (1991-2023) that includes 60-70% of Hawaii's HCC cases.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!