A naturally occurring carotenoid, lutein, reduces PDGF and H2O2 signaling and compromised migration in cultured vascular smooth muscle cells

<p>Abstract</p> <p>Background</p> <p>Platelet-derived growth factor (PDGF) is a potent stimulator of growth and motility of vascular smooth muscle cells (VSMCs). Abnormalities of PDGF/PDGF receptor (PDGFR) are thought to contribute to vascular diseases and malignancy. We previously showed that a carotenoid, lycopene, can directly bind to PDGF and affect its related functions in VSMCs. In this study we examined the effect of the other naturally occurring carotenoid, lutein, on PDGF signaling and migration in VSMCs.</p> <p>Methods</p> <p>Western blotting was performed to examine PDGF and H₂O₂signaling. Flowcytometry was used to determine PDGF binding to VSMCs. Fluorescence microscopy was performed to examine intracellular ROS production. Modified Boyden chamber system (Transwell apparatus) was used for migration assay.</p> <p>Results</p> <p>Lutein reduced PDGF signaling, including phosphorylation of PDGFR-β and its downstream protein kinases/enzymes such as phospholipase C-γ, Akt, and mitogen-activated protein kinases (MAPKs). Although lutein possesses a similar structure to lycopene, it was striking that lutein inhibited PDGF signaling through a different way from lycopene in VSMCs. Unlike lycopene, lutein not only interacted with (bound to) PDGF but also interfered with cellular components. This was evidenced that preincubation of PDGF with lutein and treatment of VSMCs with lutein followed by removing of lutein compromised PDGF-induced signaling. Lutein reduced PDGF-induced intracellular reactive oxygen species (ROS) production and attenuated ROS- (H₂O₂-) induced ERK1/2 and p38 MAPK activation. A further analysis indicated lutein could inhibit a higher concentration of H₂O₂-induced PDGFR signaling, which is known to act through an oxidative inhibition of protein tyrosine phosphatase. Finally, we showed that lutein functionally inhibited PDGF-induced VSMC migration, whereas its stereo-isomer zeaxanthin did not, revealing a special action of lutein on VSMCs.</p> <p>Conclusions</p> <p>Our study reveals a differential action mechanism of lutein from other reported caroteinoids and suggests a possible beneficial effect of lutein but not zeaxanthin on prevention of vascular diseases.</p

Forgotten stone in a ureteral stump increased the risk of an ureterocutaneous fistula

AbstractHere we report a female patient with diabetes who underwent right nephrectomy 18 years ago for pyonephrosis and renal stone formation. Before she was performed the right nephrectomy, a ureteral calculus impacted in the right ureteral stump was diagnosed. However, after 18 years, a right ureterocutaneous fistula was diagnosed, and the calculus was still found in the ureteral stump of the patient. As a result, a fistula caused by the ureter-impacted calculus was highly suspected. We successfully performed a right ureterectomy, fistulectomy, and debridement on the patient. From our experience in this case, we strongly recommend that a calculus impacted in the ureteral stump should be removed to prevent the occurrence of postoperative complications such as ureterocutaneous fistula

Exploring the Impacts of Web-Based e-Procurement on Organizational Performance

Web-enabled applications for business-to-business (B2B) procurement are not only expected to reduce the cost of purchasing process but also to alter the activities of purchasing, transform the purchasing process from an operational into a strategic activity, and provide opportunities for improving market coordination by reducing asset specificity and by making additional partners available. From organizational and inter-organizational perspectives, this study proposes a performance impact model of implementing Web-based e-procurement system for direct procurement. In the performance impact model, the strategic dimension is about partner relationship, and the operational efficiency dimension includes supplier performance, buyer performance, process integration, and process automation. Based on a survey of Taiwanese manufacturing firms, the results of this study show that the electronic execution of purchasing activities improves both of the operational efficiency dimension and the strategic dimension. The results demonstrate implementing Web-based e-procurement system not only could enhance the performance of the buyer organization but also could enhance the performance of the supplier organization and improve partner relationship management

Bilateral Ureteral Leiomyoma With Bilateral Ureteropelvic Junction Obstruction

Leiomyomas are benign tumors characterized by overgrowth of visceral smooth muscle in the respiratory, gastrointestinal, and female reproductive tracts. They rarely develop in the urinary system and only 10 cases of unilateral ureteral leiomyoma (UL) have been reported since 1955. No cases of bilateral UL or ureteropelvic junction obstruction due to UL have ever been reported. We present a case of bilateral UL with bilateral ureteropelvic junction obstruction. To the best of our knowledge, this is the first such case report in the English literature

Activation of Endothelial Cells by Antiphospholipid Antibodies—A Possible Mechanism Triggering Thrombosis in Patients with Antiphospholipid Syndrome

Antiphospholipid syndrome (APS) is an antibody-mediated hypercoagulable state characterized by recurrent venous and arterial thromboembolic events. The presence of serum antibodies are collectively termed as antiphospholipid antibodies (aPL) and is the hallmark of the disease. Interest in the pathogenesis has mostly been focused on the blood coagulation factor. However, endothelial cells might play an important role. When stimulated, cell membrane would flip to expose negatively charged phospholipids and activation markers such as adhesive molecules may appear. We consider that these changes may play an important role in the initiation of the thrombotic process when endothelial cells encounter aPL. In this study, we incubated human umbilical vein endothelial cells (HUVECs) with IgG isolated from patients with APS and found that the HUVECs were activated by the expression of negatively charged phospholipids, as shown by high annexin V binding and negative propidium iodide staining and by an increase in the level of intracellular cell adhesion molecule-1 on the cell surface. The above findings indicate that endothelial cells can be activated on exposure to aPL and trigger the thrombotic event

Rupture of Renal Pelvis in an Adult with Congenital Ureteropelvic Junction Obstruction After Blunt Abdominal Trauma

Isolated injury to the renal pelvis following blunt abdominal trauma is very rare. However, a pre-existing renal abnormality will increase the risk of rupture. We present a 24-year-old man with rupture of the left renal pelvis following blunt abdominal trauma. He had pre-existing left ureteropelvic junction (UPJ) obstruction. Delayed computed tomography scan with excretory phase revealed contrast medium extravasation from the left UPJ, and left renal pelvis rupture was diagnosed. He was managed successfully with ureteral double-J stenting for 2 months

Evaluation of Intrarenal Blood Flow by Doppler Ultrasonography Immediately after Extracorporeal Shock Wave Lithotripsy on Hydronephrotic Kidney

Extracorporeal shock wave lithotripsy (ESWL) is an effective and relatively noninvasive mode of treatment for urinary calculi. The aim of this study was to test whether therapeutic ESWL induces changes in renal parenchymatous blood flow and to evaluate shock wave side effects on the renal parenchyma. A total of 45 patients who underwent ESWL for ureteropelvic stone between January 2002 and July 2003 were included in this prospective study. Color Doppler sonography before and 30 minutes after ESWL showed no significant morphologic change. Resistive index (RI) was used to estimate renovascular resistance. The RI significantly increased in obstructed hydronephrotic kidneys. However, no significant change was observed in both treated and untreated kidneys before and after treatment. Hydronephrotic kidneys do not have a higher risk of post-ESWL renovascular resistance interference. The measurement of changes in RI with Doppler ultrasonography may provide useful information for clinical diagnosis of renal tubulointerstitial and vascular damage

Hispolon Protects against Acute Liver Damage in the Rat by Inhibiting Lipid Peroxidation, Proinflammatory Cytokine, and Oxidative Stress and Downregulating the Expressions of iNOS, COX-2, and MMP-9

The hepatoprotective potential of hispolon against carbon tetrachloride (CCl4)-induced liver damage was evaluated in preventive models in rats. Male rats were intraperitoneally treated with hispolon or silymarin once daily for 7 consecutive days. One hour after the final hispolon or silymarin treatment, the rats were injected with CCl4. Administration with hispolon or silymarin significantly decreased the alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in serum and increased the activities of superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), and glutathione (GSH) content and decreased the malondialdehyde (MDA) content in liver compared with CCl4-treated group. Liver histopathology also showed that hispolon reduced the incidence of liver lesions induced by CCl4. In addition, hispolon decreased nitric oxide (NO) production and tumor necrosis factor (TNF-α), inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) activation in CCl4-treated rats. We also examined the involvement of matrix metalloproteinase (MMP)-9 in the development of CCl4-induced liver damage in rats. Hispolon inhibited the expression of MMP-9 protein, indicating that MMP-9 played an important role in the development of CCl4-induced rat liver damage. Therefore, we speculate that hispolon protects rats from liver damage through their prophylactic redox balancing ability and anti-inflammation capacity

The Incremental Diagnostic Performance of Coronary Computed Tomography Angiography Added to Myocardial Perfusion Imaging in Patients with Intermediate-to-High Cardiovascular Risk

Purpose: Several studies have suggested that a combined approach of stress myocardial perfusion imaging (MPI) and coronary computed tomography angiography (CCTA) can provide diagnostic results with excellent accuracy. We aimed to explore whether the addition of CCTA to stress MPI provides incremental diagnostic value in intermediate-to-high cardiovascular risk patients. Methods: A total of 106 consecutive patients (93 male, 65 ± 10.4 years) underwent coronary artery calcium scoring (CACS), CCTA and 201 Thallium stress MPI before coronary angiography was reviewed. Thirty-seven patients (34.9%) had a history of proven coronary artery disease (CAD) or revascularization procedures, and four had documented non-significant CAD (3.8%). The remaining patients consisted of 17 (16.0%) classified as intermediate, and 48 (45.3%) as the high-risk groups. Results: Obstructive CAD was diagnosed by invasive coronary angiography in 88 patients with 161 vessels. The sensitivity and specificity in a patient-based analysis for obstructive CAD were 99% and 17% for CCTA, 80% and 50% for MPI and 91% and 67% for the combined method, respectively. The per-vessel diagnostic sensitivity and specificity were 95% and 54% for CCTA, 59% and 75% for MPI and 84% and 76% for the combined method. There were significant differences (p &lt; 0.05) when comparing the combined method with MPI or CCTA by areas under the curve in a patient-or vessel-based analysis. However, CACS of 400 or more could not further stratify the patients with obstructive CAD. Conclusions: CCTA, not CACS, provided additional diagnostic values to stress MPI in patients with intermediateto-high cardiovascular risk