RESUMO
Increased mean platelet volume (MPV) is a marker of platelet activation. Platelet activation with cocaine use is not well studied. We wanted to investigate MPV levels in patients with cocaine-associated chest pain (CACP) as a marker of platelet activation. Retrospectively, MPV of 82 consecutive patients with CACP (group 1) with positive urine drug screen (UDS), without acute myocardial infarction (AMI) (group 1A) and with AMI with elevated troponin (group 1B), were included in the study. The control group (group 2) consisted of 89 consecutive patients admitted during the same time period with acute chest pain (ACP) who had negative UDS and negative cardiac markers with a normal cardiac stress test or normal coronary angiogram. Analysis showed no statistically significant difference of MPV between group 1, 8.46 ± 1.06 fL, versus group 2, 8.7 ± 1.07 fL; p = 0.142; and between group 1A, 8.46 ± 1.05 fL, and group 1B, 8.46 ± 1.09 fL; p = 0.983. By multiple linear regression analysis, MPV was not influenced by cocaine abuse (R = 0.269, R (2) = 0.072, adjusted R (2) = -0.009, p = 0.562). MPV is not elevated in patients with cocaine use even when they had AMI. Further studies may be necessary to investigate the role of platelet activation in patients with cocaine use and chest pain.
RESUMO
BACKGROUND: Hydrogen sulfide (H2S) has been implicated in regulating cardiovascular pathophysiology in experimental models. However, there is a paucity of information regarding the levels of H2S in health and cardiovascular disease. In this study we examine the levels of H2S in patients with cardiovascular disease as well as bioavailability of nitric oxide and inflammatory indicators. METHODS AND RESULTS: Patients over the age of 40 undergoing coronary or peripheral angiography were enrolled in the study. Ankle brachial index (ABI) measurement, measurement of plasma-free H2S and total nitric oxide (NO), thrombospondin-1 (TSP-1), Interleukin-6 (IL-6), and soluble intercellular adhesion molecule-1 (sICAM-1) levels were performed. Patients with either coronary artery disease alone (n = 66), peripheral arterial disease (PAD) alone (n = 13), or any vascular disease (n = 140) had higher plasma-free H2S levels compared to patients without vascular disease (n = 53). Plasma-free H2S did not distinguish between disease in different vascular beds; however, total NO levels were significantly reduced in PAD patients and the ratio of plasma free H2S to NO was significantly greater in patients with PAD. Lastly, plasma IL-6, ICAM-1, and TSP-1 levels did not correlate with H2S or NO bioavailability in either vascular disease condition. CONCLUSIONS: Findings reported in this study reveal that plasma-free H2S levels are significantly elevated in vascular disease and identify a novel inverse relationship with NO bioavailability in patients with peripheral arterial disease.
Assuntos
Doenças Cardiovasculares/sangue , Sulfeto de Hidrogênio/sangue , Doença Arterial Periférica/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/sangueRESUMO
Curcumin appears to be a safe, bioactive food compound that is a potential chemopreventive for patients at a high risk for head and neck squamous cell carcinoma (HNSCC). Identification and validation of intermediate endpoints is an important step in evaluating chemopreventive agents. AKT/MTOR pathway biomarkers are intrinsic to the carcinogenic process as well as the mechanism of intervention with curcumin. Antiproliferative effects of curcumin were assayed in 9 HNSCC and a keratinocyte cell line. Nicotine, a genotoxic alkaloid involved in tobacco addiction, forms DNA adducts and has been implicated in upper aerodigestive tract cancer promotion. The antiproliferative effects of curcumin were associated with inhibition of the AKT/MTOR pathway in presence and absence of nicotine, which also induced this pathway. Curcumin was highly effective at suppressing growth of SCC40 xenografts and its activity is associated with modulation of MTOR's downstream target pS6. Curcumin at 15 mg significantly increased survival (286 ± 37 vs. 350 days) in the 4NQO carcinogenic model survival study. A major cause of lethal progression of HNSCC is local regional migration and invasion of malignant cells, and curcumin significantly inhibited cancer cell migration and invasion in vitro and in vivo where downregulation of pS6 was associated with a significant decrease in MMP-9. This is the first study to demonstrate that curcumin inhibits the adverse effects of nicotine by blocking nicotine-induced activation of the AKT/MTOR pathway in HNSCC, which retards cell migration. These studies indicate that inhibiting the AKT/MTOR pathway with curcumin may be useful as an oral chemopreventive agent.