Effect of sodium-glucose co-transporter-2 inhibitors on coronary blood flow in patients with type 2 diabetes mellitus.

OBJECTIVE: Type 2 diabetes mellitus (T2DM) is known to be associated with endothelial dysfunction (ED). Reducing ED can attenuate the occurrence of cardiovascular diseases. One of the indicators of ED is decreased coronary blood flow (CBF). Sodium-glucose co-transporter 2 inhibitors (SGLT-2is) are known to directly improve ED in both euglycemic and hyperglycemic conditions and have been shown to decrease the incidence of major cardiovascular events. We aimed to investigate whether SGLT-2is improves CBF in patients with T2DM, who have angiographically normal or nearly normal coronary arteries. PATIENTS AND METHODS: In this single-center retrospective study, all patients who underwent coronary angiography between January 2017 and September 2022 were screened. We designed the study by dividing the patients into two groups - those who used conventional antidiabetic medications (CAM) together with SGLT-2is (patients using an SGLT-2 inhibitor for at least 3 months) and those who used only conventional antidiabetic medications. Of the 18,205 patients who underwent coronary angiography, 5,040 patients had T2DM. After exclusion, 288 patients were divided into two groups - those who used CAM together with SGLT-2is and those who used only CAM. CBF was assessed by thrombolysis in myocardial infarction (TIMI) frame counting. RESULTS: Two hundred eighty-eight patients who had T2DM and met the inclusion criteria were included in our study. The patients were divided into two groups - those who used CAM together with SGLT-2is (n = 75) and those who used only CAM (n = 213). The median age in the group that used CAM together with SGLT-2is was 55 (51-64), where 52 (69.3%) patients were female. The mean TIMI frame count (TFC) was 23.5 in the group using CAM + SGLT-2is and 27.5 in the group using only CAM. In the multivariable linear regression analysis, the mean TFC was significantly lower in the group using CAM together with SGLT-2is compared to the group using only CAM [ß-coefficient = -12.766, 95% Cl: -5.304; -3.887, p < 0.001]. Moreover, there was a statistically significant correlation between an increase in BMI and hemoglobin with an increase in the mean TFC [ß-coefficient = 3.018, 95% Cl 0.037-0.175, p = 0.003 and ß-coefficient = 2.316, 95% Cl 0.033-0.405, p = 0.021, respectively]. CONCLUSIONS: We have demonstrated that the use of SGLT-2is improves coronary artery blood flow in patients with T2DM who have normal or nearly normal coronary angiography.

A post-reconstruction method to correct cupping artifacts in cone beam breast computed tomography.

In cone beam breast computed tomography (CT), scattered radiation leads to nonuniform biasing of CT numbers known as a cupping artifact. Besides being visual distractions, cupping artifacts appear as background nonuniformities, which impair efficient gray scale windowing and pose a problem in threshold based volume visualization/segmentation. To overcome this problem, we have developed a background nonuniformity correction method specifically designed for cone beam breast CT. With this technique, the cupping artifact is modeled as an additive background signal profile in the reconstructed breast images. Due to the largely circularly symmetric shape of a typical breast, the additive background signal profile was also assumed to be circularly symmetric. The radial variation of the background signals was estimated by measuring the spatial variation of adipose tissue signals in front view breast images. To extract adipose tissue signals in an automated manner, a signal sampling scheme in polar coordinates and a background trend fitting algorithm were implemented. The background fits compared with targeted adipose tissue signal value (constant throughout the breast volume) to get an additive correction value for each tissue voxel. To test the accuracy, we applied the technique to cone beam CT images of mastectomy specimens. After correction, the images demonstrated significantly improved signal uniformity in both front and side view slices. The reduction of both intraslice and interslice variations in adipose tissue CT numbers supported our observations.

Procarbazine, CCNU, vincristine combination in the treatment of brain tumors.

Forty patients with primary malignant brain tumor were treated by combination chemotherapy after prior treatment with surgery and radiotherapy. The chemotherapy schedule consisted of PCV: procarbazine per os, 100 mg/m2, during 14 consecutive days; CCNU, per os, 80 mg/m2 on day 1 and vincristine, intravenously, 1.4 mg/m2 on days 1 and 14. This protocol was planned to be repeated every 45 days for 6 courses. Median 5 courses (range, 2-6) of chemotherapy was administered to patients. The median relapse free (RFS) and overall survival (OS) rates were found to be 28 and 79+ months, respectively. According to univariate analysis, performance status (PS) of patients was an important prognostic factor on RFS and OS where extent of surgery was an additional significant determinant of OS. Multivariate analysis of pretreatment factors revealed the influence of sex, type of histopathology and PS on RFS and that of PS on OS rates (P < 0.05). The toxicity of this regimen was mild to moderate. The major toxicity noted was myelosuppression. Severe (grade III-IV) neutropenia and thrombocytopenia has been observed in 13 (7%) and 6 courses (3.5%), respectively. In general, PCV is well tolerated and the median RFS and OS times elucidated are comparable with particular trials utilizing combination chemotherapy and longer than using radiotherapy alone.