Effect of a thin-tipped short bevel needle for peripheral intravenous access on the compressive deformation and displacement of the vein: A preclinical study.

BACKGROUND: Peripheral intravenous catheter (PIVC) insertion often fails on the first attempt. Risk factors include small vein size and dehydration, causing vein deformation and displacement due to puncture resistance of the vessel. The authors developed a short, thin-tipped bevel needle and compared its puncture performance with needles of four available PIVCs using an ex vivo model. METHODS: The PIVC with the thin-tipped short bevel needle was compared to four available PIVCs using an ex vivo model which simulated the cephalic vein of the human forearm. The ex vivo model consisted of a porcine shoulder and porcine internal jugular vein, and was used for evaluation of the rate of vein deformation and vessel displacement during needle insertion. RESULTS: An ex vivo model was created with a vessel diameter of 2.7-3.7 mm and a depth of 2-5 mm. The thin-tipped short bevel PIVC needle was associated with a significantly lower compressive deformation rate and venous displacement compared to the needles of the other four PIVCs. CONCLUSION: The thin-tipped short bevel needle induced lower compressive deformation and displacement of the vein than the conventional needles. This needle has the potential to improve the first-attempt success rate of peripheral intravenous catheterization in patients with difficult venous access.

Relationship between QRS score and microvascular obstruction after acute anterior myocardial infarction.

BACKGROUND: The QRS score on electrocardiogram (ECG) in patients with myocardial infarction (MI) reportedly reflects the severity of myocardial damage. The presence of microvascular obstruction (MO) assessed by cardiac magnetic resonance (CMR) imaging is associated with irreversible myocardial damage. MO assessed by CMR is known to be a predictor for adverse clinical outcome after ST-elevation MI. The aim of the present study was to examine the relationship between QRS score and MO in acute anterior MI patients. METHODS: Sixty-two patients with first acute anterior MI who successfully underwent primary percutaneous coronary intervention (PCI) were enrolled. The QRS score after PCI on admission ECG was calculated by a Selvester-Wagner QRS scoring system. CMR imaging was performed at 11.4±3.9 days after MI. MO was defined as delayed enhancement with contrast-devoid core. Patients were divided into two groups as follows: 37 patients who showed MO (MO group) and 25 patients who did not show it (non-MO group). RESULTS: The QRS score was significantly greater in the MO group than in the non-MO group. The QRS score significantly correlated with MO volume (r=0.418, p=0.010). Multivariate analysis showed that the QRS score (odds ratio 1.362, 95% CI: 1.038-1.951, p=0.024) and the peak creatine kinase levels (odds ratio 1.001, 95% CI: 1.000-1.002, p<0.001) were independent predictors for MO. CONCLUSIONS: Our results indicate that the QRS score derived from simple and widely available ECG may be a useful parameter for assuring the presence of MO.

Microvascular obstruction on delayed enhancement cardiac magnetic resonance imaging after acute myocardial infarction, compared with myocardial (201)Tl and (123)I-BMIPP dual SPECT findings.

BACKGROUND: The hypo-enhanced regions within the hyper-enhanced infarct areas detected by cardiac magnetic resonance (CMR) imaging reflect microvascular obstruction (MO) after acute myocardial infarction (AMI). The combined myocardial thallium-201 ((201)Tl)/iodine-123-15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid ((123)I-BMIPP) dual single-photon emission computed tomography (SPECT) is a useful tool for detecting myocardial reversibility after AMI. We evaluated whether MO could be an early predictor of irreversible myocardial damage in comparison with (201)Tl and (123)I-BMIPP dual SPECT findings in AMI patients. METHODS: Sixty-two patients with initial AMI who successfully underwent coronary revascularization were enrolled. MO was defined by CMR imaging. Patients were divided into 2 groups as follows: MO group (n=32) and non-MO group (n=30). Scintigraphic defect scores were calculated using a 17-segment model with a 5-point scoring system. The mismatch score (MMS) was calculated as follows: the total sum of (Σ) (123)I-BMIPP defect score minus Σ(201)Tl defect score. The percentage mismatch score (%MMS) was calculated as follows: MMS/(Σ(123)I-BMIPP score)×100 (%). RESULTS: The percentage infarct size (%IS) was significantly greater in the MO group than in the non-MO group (32.2±13.8% vs. 18.3±12.1%, p<0.001). The %MMS significantly correlated with the %IS and the percentage MO (r=-0.26, p=0.03; r=-0.45, p<0.001, respectively). The %MMS was significantly greater in the non-MO group than in the MO group (45.4±42.4% vs. 13.3±28.0%, p=0.001), and was an independent predictor for MO (OR 0.97, 95%CI 0.94-0.99, p=0.02). CONCLUSIONS: Our results reconfirm that, in comparison with myocardial dual scintigraphy, MO is an important structural abnormality. CMR imaging is useful for the early detection of irreversible myocardial damage after AMI.

Differentiation capacity of endothelial progenitor cells correlates with endothelial function in healthy young men.

BACKGROUND: Endothelial progenitor cells (EPCs) have been assumed to maintain vascular endothelial integrity, so the present study investigated whether the functional capacity of EPCs correlates with endothelial function in healthy young subjects, as has been confirmed in aged subjects with atherosclerotic disease. METHODS AND RESULTS: EPCs in 41 healthy, young male nonsmokers (age 33.1 +/-3.9 years, mean +/- SD) were characterized. The correlation between flow-mediated vasodilation (FMD) and the number of EPCs or the plasma concentrations of growth factors, such as vascular endothelial growth factor, did not reach statistical significance. However, FMD was significantly correlated with the EPC differentiation index, defined as the ratio of the number of EPCs to the total number of adherent cells (r=0.391, P=0.011) and the abundance of endothelial nitric oxide synthase mRNA (r=0.340, P=0.030). CONCLUSIONS: In healthy young men, despite a lack of correlation of the number or colony counts of EPCs, the ability of circulating progenitor cells to differentiate into an endothelial lineage is closely correlated with endothelial function. This cell function assay may serve as a novel biomarker for vascular function in healthy subjects in the pre-atherosclerotic stage.

Formation and recovery of a cell sheet by a particle monolayer with the surface roughness.

We studied the topographical effect of roughness displayed by a closely packed particle monolayer on formation of a cell monolayer (cell sheet). Particle monolayers were prepared by Langmuir-Blodgett deposition using particles, which were 527nm (SA053) and 1270nm (SA127) in diameter. Human umbilical vein endothelial cells (HUVECs) were seeded at a high density (2.0 x10(5)cells/cm(2)) onto particle monolayers. It was found that cells gradually became into contact with adjacent cells on the SA053 monolayer and the formed cell sheet could be readily detached from the particle monolayer by gentle pipetting. On the other hand, cells adhering onto the tissue culture polystyrene (TCPS) and the SA127 particle monolayer were difficult to peel off. At a low cell seeding density (5.0x10(4)cells/cm(2)), pre-coating with bovine plasma fibronectin (FN) allowed cell growth on an SA053 particle monolayer, and a confluent monolayer was able to be peeled as a cell sheet from the particle monolayer just by pipetting. By immunostaining of human fibronectin, we found that fibronectin was secreted and concentrated onto the substrate side of a cell sheet. The obtained cell sheet adhered and grew on the TCPS again within 20min.

Impact of low-density lipoprotein particle size on carotid intima-media thickness in patients with type 2 diabetes mellitus.

Small low-density lipoprotein (LDL) particles and modifications to LDL such as glycation and oxidation have been linked to the pathogenesis of atherosclerosis in patients with diabetes. We investigated whether LDL particle size, or the levels of glycated LDL or malondialdehyde-modified LDL (MDA-LDL) are associated with carotid intima-media thickness (IMT) in patients with type 2 diabetes mellitus. One hundred seventy-two patients with type 2 diabetes mellitus were enrolled. Carotid IMT was measured by high-resolution ultrasound, and LDL particle size and serum glycated LDL and MDA-LDL levels were determined. The 3 variables were significantly correlated with one another. Univariate analyses defined statistically significant correlations of carotid IMT with LDL size, hemoglobin A(1c), glycated LDL, MDA-LDL, high-density lipoprotein (HDL) cholesterol, and age. The strongest association of IMT was with LDL size (r = -0.406, P < .0001), followed by that with HDL cholesterol (r = -0.225, P = .004). A stepwise multiple regression analysis revealed that LDL size and HDL cholesterol are independent predictors of carotid IMT. Neither glycated LDL nor MDA-LDL had a significant independent contribution to the severity of carotid IMT in the multivariate model. Low-density lipoprotein particle size, but not the glycated LDL or MDA-LDL level, was independently associated with carotid IMT in patients with type 2 diabetes mellitus regardless of antidiabetic and lipid-lowering medications. These results suggest that the measurement of LDL size may be more useful than quantification of modified LDLs for assessing atherosclerosis in patients with type 2 diabetes mellitus. Small LDL particles may be the most important predictor for the risk of cardiovascular disease in diabetic patients.

Subcellular topological effect of particle monolayers on cell shapes and functions.

We studied topological effects of subcellular roughness displayed by a closely packed particle monolayer on adhesion and growth of endothelial cells. Poly(styrene-co-acrylamide) (SA) particles were prepared by soap-free emulsion copolymerization. Particle monolayers were prepared by Langmuir-Blodgett deposition using particles, which were 527 (SA053) and 1270 nm (SA127) in diameter. After 24-h incubation, cells tightly adhered on a tissue culture polystyrene dish and randomly spread. On the other hand, cells attached on particle monolayers were stretched into a narrow stalk-like shape. Lamellipodia spread from the leading edge of cells attached on SA053 monolayer to the top of the particles and gradually gathered to form clusters. This shows that cell-cell adhesion became stronger than cell-substrate interaction. Cells attached to SA127 monolayer extended to the reverse side of a particle monolayer and engulfed particles. They remained immobile without migration 24h after incubation. This shows that the inhibition of extensions on SA127 monolayer could inhibit cell migration and cell proliferation. Cell growth on the particle monolayers was suppressed compared with a flat TCPS dish. The number of cells on SA053 gradually increased, whereas that on SA127 decreased with time. When the cell seeding density was increased to 200,000 cells cm(-2), some adherent cells gradually became into contact with adjacent cells. F-actin condensations were formed at the frame of adherent cells and the thin filaments grew from the edges to connect each other with time. For the cell culture on SA053 monolayer, elongated cells showed a little alignment. Cells showed not arrangement of actin stress fibers but F-actin condensation at the contact regions with neighboring cells. Interestingly, the formed cell monolayer could be readily peeled from the particle monolayer. These results indicate that endothelial cells could recognize the surface roughness displayed by particle monolayers and the response was dependent on the pitch of particle monolayers.

Impact of plasma aldosterone levels for prediction of in-stent restenosis.

Aldosterone promotes vascular smooth muscle cell proliferation and endothelial dysfunction, suggesting the contribution to in-stent restenosis (ISR). This study evaluated any relation between plasma aldosterone levels and ISR 6 months after successful coronary stenting. We enrolled 156 consecutive patients with stable angina who underwent coronary bare metal stenting. Plasma aldosterone levels and other serum markers known to influence cardiovascular events were measured in all patients at baseline. Patients with restenosis were found to have significantly higher plasma aldosterone levels than their counterparts without restenosis (162 +/- 60 vs 122 +/- 60 pg/ml, p = 0.007). On logistic regression analysis, even after adjusting for clinical, angiographic, and other confounding variables, plasma aldosterone level per 10 pg/ml (odds ratio 1.34, 95% confidence interval 1.10 to 1.63, p = 0.006) proved to be the independent predictor of ISR. The area under the receiver-operating characteristic curve for plasma aldosterone level was 0.75, and the optimal cut-off value identified by receiver-operating characteristic analysis was 141.9 pg/ml, which had a predictive accuracy of 69%. In conclusion, the present findings indicate that plasma aldosterone levels at baseline are independent predictors of ISR and may constitute a potential therapeutic target.

Inverse correlation between soluble CD40 ligand and soluble CD40 is absent in patients with unstable angina.

The CD40/CD40 ligand (CD40L) system mediates inflammatory processes important in atherogenesis and plaque instability. The expression of CD40L on activated T cells was suppressed by soluble CD40 (sCD40) in vitro. However, the relationship between soluble CD40L (sCD40L) and sCD40 in unstable angina (UA) is still unknown. Thirty-seven consecutive patients with recent chest pain or discomfort were recruited. Patients with both Braunwald's class IB-IIIB and with coronary stenosis (or stenoses) of >75% were assigned to the UA group (n = 19, aged 67.2 +/- 8.2 years), and the rest to the control group (n = 18, aged 63.4 +/- 8.7 years). The serum levels of sCD40L and sCD40, and the plasma levels of matrix metalloproteinase (MMP)-9, were measured by enzyme-linked immunosorbent assays. A significantly inverse correlation between sCD40L and sCD40 was shown in the controls (r = -0.72, P = 0.0007), but was absent in the UA group (r = -0.16, P not significant), although there was no statistical significance between these groups in terms of serum levels of sCD40L or sCD40. The difference of the regression slopes of these regression lines was statistically significant (P < 0.01). Additionally, there was a significant correlation between sCD40 and plasma levels of MMP-9 in the patients with and without UA (r = 0.58, P = 0.0096), but no significant correlation between sCD40L and MMP-9 levels (r = 0.00, P not significant). The balance between CD40 and CD40L may be lost in patients with UA. Soluble CD40 expression may also be related to MMP-9 expression in atherosclerotic tissues.

One-step highly diastereoselective synthesis of gamma-aminoalkyl-substituted gamma-butyrolactones by an asymmetric samarium-mediated ketyl-alkene coupling reaction.

The samarium(II) iodide mediated reaction of N,N-dibenzyl-protected (S)-alpha-amino aldehydes with (1S,2R)-N-methylephedrinyl acrylate gave the (4R,1'S)-gamma-(aminoalkyl)-gamma-butyrolactones in good yields with high diastereoselectivities (up to 80% de); (4R,1'S)-gamma-amino-(2-phenylethyl)-gamma-butyrolactone (6a), which should be a potent precursor for gamma-secretase inhibitors, was obtained with high de value.