Bilateral inferior petrosal sinus sampling: validity, diagnostic accuracy in lateralization of pituitary microadenoma, and treatment in eleven patients with Cushing's syndrome - a single-center retrospective cohort study.

BACKGROUND: This single-center retrospective cohort study aimed to describe the findings and validity of Bilateral inferior petrosal sinus sampling (BIPSS) in the differential diagnosis of patients with ACTH-dependent Cushing's syndrome (CS). METHODS: Eleven patients underwent BIPSS due to equivocal biochemical tests and imaging results. Blood samples were taken from the right inferior petrosal sinus (IPS), left IPS, and a peripheral vein before and after stimulation with desmopressin (DDAVP). ACTH and prolactin levels were measured. The diagnosis was based on the ACTH ratio between the IPS and the peripheral vein. Also, lateralization of pituitary adenoma in patients with Cushing's disease (CD) was predicted. No significant complications were observed with BIPSS. RESULTS: Based on the pathology report, eight patients had CD, and three had ectopic ACTH syndrome (EAS). Unstimulated BIPSS resulted in a sensitivity of 87.5%, specificity of 100%, PPV of 100%, NPV of 75%, and accuracy of 91%. Stimulated BIPSS resulted in a sensitivity of 100%, specificity of 100%, PPV of 100%, NPV of 100%, and accuracy of 100%. However, pituitary magnetic resonance imaging (MRI) had a lower diagnostic accuracy (sensitivity:62.5%, specificity:33%, PPV:71%, NPV:25%, accuracy:54%). BIPSS accurately demonstrated pituitary adenoma lateralization in 75% of patients with CD. CONCLUSIONS: This study suggests that BIPSS may be a reliable and low-complication technique in evaluating patients with ACTH-dependent CS who had inconclusive imaging and biochemical test results. The diagnostic accuracy is improved by DDAVP stimulation. Pituitary adenoma lateralization can be predicted with the aid of BIPSS.

Vitamin C supplementation lowers advanced glycation end products (AGEs) and malondialdehyde (MDA) in patients with type 2 diabetes: A randomized, double-blind, placebo-controlled clinical trial.

This study evaluated how daily vitamin C administration impacts systemic oxidative stress and inflammation and its safety in T2D patients. This randomized, double-blinded, placebo-controlled, parallel-arm clinical trial included 70 patients with T2D. They were allocated to receive either 500 mg/day of vitamin C or a matching placebo for 8 weeks. Of the 70 subjects assigned to the trial, 57 were included in the statistical analysis (vitamin C: n = 32, placebo: n = 25). Inflammatory and oxidative markers, including advanced glycation end products (AGEs), malondialdehyde (MDA), advanced oxidation protein products (AOPP), oxidized low-density lipoprotein (ox-LDL), highly sensitive C-reactive protein (hs-CRP), tumor necrosis factor-α (TNF-α), and ferric reducing ability of plasma (FRAP) were measured at baseline and the end of the trial. In addition, vitamin C tolerance was evaluated. A nutritionist visited all participants for a standard diabetic regimen. Following vitamin C supplementation, the serum levels of MDA (p-value < .001) and AGEs (p-value = .002) demonstrated a significant decrease after controlling for multiple confounders, including age, blood pressure, waist circumference, HbA1C, TG, and LDL-C, while no significant changes were observed for AOPP (p-value = .234) and ox-LDL (p-value = .480). The FRAP showed an increasing trend as an antioxidant marker but was not statistically significant (p-value = .312). The hs-CRP and TNF-α had no significant changes (p-value: .899 and .454, respectively). Also, no major adverse events were observed. Vitamin C supplementation may be beneficial in reducing AGEs and MDA in patients with T2D.

Lipid profile, ox-LDL, and LCAT activity in patients with endometrial carcinoma and type 2 diabetes: The effect of concurrent disease based on a case-control study.

Background and Aim: The role of lecithin: cholesterol acyltransferase (LCAT) and oxidized low-density lipoprotein (ox-LDL) in endometrial cancer (EC) or EC with concurrent type 2 diabetes is still unclear. This study investigated the LCAT activity, ox-LDL, and lipid profile in EC patients with or without type 2 diabetes and compared them with healthy individuals and patients with type 2 diabetes alone. Methods: In this cross-sectional, case-control study, 93 female participants were recruited. The participants were divided into four groups, including EC with type 2 diabetes (n = 19), EC without type 2 diabetes (n = 17), type 2 diabetes (n = 31), and healthy controls (n = 26). Sociodemographic information, the LCAT activity, triglyceride (TG), total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and ox-LDL levels were collected. One-way analysis of variance and analysis of covariance, Student's t-test, Mann-Whitney U-test, and χ 2-test were used to compare demographic features and laboratory results among studied groups. Regression analyses were also performed to evaluate the interaction effect between EC and type 2 diabetes on serum LCAT activity. Results: The LCAT activity was significantly lower, and ox-LDL levels were significantly higher in all patient groups compared to the healthy controls (p < 0.001). EC patients had significantly lower LCAT activity and higher ox-LDL levels than type 2 diabetes and healthy groups (p < 0.05). Higher levels of TG and lower levels of HDL-C were observed in all patient groups compared to the healthy group (all p < 0.001). Patients with EC and concomitant type 2 diabetes had significantly lower serum LDL-C levels than healthy and type 2 diabetes groups (p < 0.05). Conclusions: The combination of EC and type 2 diabetes had a subadditive effect on LCAT activity and ox-LDL level. The lowest LCAT activity and the highest ox-LDL levels were observed in patients with EC and concurrent type 2 diabetes.