Use of a new high-sensitivity assay for cardiac troponin T to stratify the risk of cardiovascular disease in outpatients with type-2 diabetes

Alcohol flushing is independently associated with lesser degree of carotid atherosclerosis in Japanese type 2 diabetic patients

Background

Type 2 diabetes mellitus is a well-known risk factor for atherosclerosis. Intima media thickness (IMT) of the carotid arteries has been widely used for assessing atherosclerotic changes representing cerebro-cardiovascular disease risk. Previous studies have associated the presence of inactive aldehyde dehydrogenase with progression of atherosclerosis and alcohol flushing. However, reports conflict on whether alcohol flushing could potentially modify the degree of atherosclerosis in type 2 diabetic patients.

Methods

We retrospectively assessed the relationships among alcohol flushing, IMT, and clinical characteristics in 123 consecutive Japanese type 2 diabetic patients. Alcohol flushing was assessed by standardized questionnaires.

Results

Patients with alcohol flushing had lower mean IMT [0.7 (0.65-0.80) vs. 0.8 (0.73-0.90) mm, p < 0.05], despite having higher triglycerides [132 (94-169) vs. 98 (70-139) mg/dL, p < 0.01] and lower high-density lipoprotein cholesterol [52 (44-60) vs. 59 (49-67) mg/dL, p < 0.05] concentration. Patients with alcohol flushing had lower frequency of alcohol intake (45 vs. 76%, p < 0.0001). Mean IMT was positively associated with age and low-density lipoprotein cholesterol concentration, and negatively with alcohol flushing according to stepwise multiple regression analysis. Alcohol flushing was also independently associated with mean IMT by multivariate analysis.

Conclusions

These findings suggest that alcohol flushing is independently associated with lesser degree of carotid atherosclerosis in Japanese type 2 diabetic patients.

Electrochemical evaluation of troponin T imprinted polymer receptor

The selective detection and quantification of macromolecular targets is a fundamental biological mechanism in nature. Molecularly imprinted polymers (MIPs) have been identified as one of the most promising synthetic alternatives to bioreceptors. However, expanding this methodology towards selective recognition of bulky templates such as proteins appears to be extremely challenging due to problems associated with removal of the template from the polymeric network. In this study, polymer imprinted with troponin T (TnT) was assessed using electrochemical methods and the influence of various extraction methods, including conventional immersion extraction, thermal annealing and ultrasonic-assisted extraction, on the binding characteristics of the troponin-to-imprinted polymer receptor was elucidated. Cyclic voltammetric deposition of o-phenylenediamine (o-PD) film in the presence of TnT as a template was performed in acetate buffer (0.5 M, pH 5.2) on a gold substrate. Solvent extraction of the target molecule was optimised and followed by subsequent washing with water. The electrochemistry of a ferro/ferricyanide probe was used to characterise the TnT MIP receptor film. The incubation of the TnT MIP receptor-modified electrode with respect to TnT concentration resulted in a suppression of the ferro/ferricyanide redox current. The dissociation constant (KD) was calculated using a two-site model of template affinity for the TnT MIP receptor. The synthetic TnT MIP receptor had high affinity for TnT with a KD of 2.3×10(-13) M.

Level of urinary liver-type fatty acid-binding protein is associated with cardiac markers and electrocardiographic abnormalities in type-2 diabetes with chronic kidney disease stage G1 and G2

Urinary liver-type fatty acid-binding protein (L-FABP) reflects the degree of stress in proximal tubules of the kidney. We examined the level of L-FABP in type-2 diabetes mellitus (T2DM) patients with chronic kidney disease (CKD) stage G1 and G2, and its relationship with cardiac markers and electrocardiographic (ECG) abnormalities. T2DM patients whose estimated glomerular filtration rate (eGFR) was ≥60 mL/min/1.73 m(2) were recruited [n = 276 (165 males), mean age 64 years]. The median level of urinary L-FABP was 6.6 μg/gCr. Urinary L-FABP showed significant correlation with urinary albumin-to-creatinine ratio (ACR) (r = 0.51, p < 0.0001). Median (25th-75th percentile) eGFR was 82 (72-95) mL/min/1.73 m2. We divided patients into four subgroups (group 1, L-FABP ≤8.4 μg/gCr and ACR ≤30 mg/gCr; group 2, L-FABP ≤8.4 μg/gCr and ACR >30 mg/gCr; group 3, L-FABP >8.4 μg/gCr and ACR ≤30 mg/gCr; group 4, L-FABP >8.4 μg/gCr and ACR >30 mg/gCr). Compared with group 1, group 4 was significantly higher in systolic blood pressure, and eGFR using standardized serum cystatin C, high-sensitivity troponin T, and N-terminal pro-brain natriuretic peptide (NT-proBNP). Group 4 had significantly higher level of NT-proBNP than group 3. Groups 2, 3 and 4 showed more ECG abnormalities than group 1. These findings suggest that simultaneous measurement of urinary L-FABP and ACR should be useful to assess cardiovascular damage reflecting on the elevation of cardiac markers and ECG abnormalities in T2DM with CKD G1 and G2.