Anti-Microbial, Thermal, Mechanical, and Gas Barrier Properties of Linear Low-Density Polyethylene Extrusion Blow-Molded Bottles.

Microbial contamination can occur on the surfaces of blow-molded bottles, necessitating the development and application of effective anti-microbial treatments to mitigate the hazards associated with microbial growth. In this study, new methods of incorporating anti-microbial particles into linear low-density polyethylene (LLDPE) extrusion blow-molded bottles were developed. The anti-microbial particles were thermally embossed on the external surface of the bottle through two particle deposition approaches (spray and powder) over the mold cavity. The produced bottles were studied for their thermal, mechanical, gas barrier, and anti-microbial properties. Both deposition approaches indicated a significant enhancement in anti-microbial activity, as well as barrier properties, while maintaining thermal and mechanical performance. Considering both the effect of anti-microbial agents and variations in tensile bar weight and thickness, the statistical analysis of the mechanical properties showed that applying the anti-microbial agents had no significant influence on the tensile properties of the blow-molded bottles. The external fixation of the particles over the surface of the bottles would result in optimum anti-microbial activity, making it a cost-effective solution compared to conventional compounding processing.

Frequency of Cholesterol Crystals in Culprit Coronary Artery Aspirate During Acute Myocardial Infarction and Their Relation to Inflammation and Myocardial Injury.

Cholesterol crystals (CCs) have been associated with plaque rupture through mechanical injury and inflammation. This study evaluated the presence of CCs during acute myocardial infarction (AMI) and associated myocardial injury, inflammation, and arterial blood flow before and after percutaneous coronary intervention. Patients presenting with AMI (n = 286) had aspiration of culprit coronary artery obstruction. Aspirates were evaluated for crystal content, size, composition, and morphology by scanning electron microscopy, crystallography, and infrared spectroscopy. These were correlated with inflammatory biomarkers, cardiac enzymes, % coronary stenosis, and Thrombolysis in Myocardial Infarction (TIMI) blush and flow grades. Crystals were detected in 254 patients (89%) and confirmed to be cholesterol by spectroscopy. Of 286 patients 240 (84%) had CCs compacted into clusters that were large enough to be measured and analyzed. Moderate to extensive CC content was present in 172 cases (60%). Totally occluded arteries had significantly larger CC clusters than partially occluded arteries (p <0.05). Patients with CC cluster area >12,000 µm2 had significantly elevated interleukin-1 beta (IL-1ß) levels (p <0.01), were less likely to have TIMI blush grade of 3 (p <0.01), and more likely to have TIMI flow grade of 1 (p <0.01). Patients with recurrent AMI had smaller CC cluster area (p <0.04), lower troponin (p <0.02), and IL-1ß levels (p <0.04). Women had smaller CC clusters (p <0.04). Macrophages in the aspirates were found to be attached to CCs. Coronary artery aspirates had extensive deposits of CCs during AMI. In conclusion, presence of large CC clusters was associated with increased inflammation (IL-1ß), increased arterial narrowing, and diminished reflow following percutaneous coronary intervention.

Role of cholesterol crystals in atherosclerosis is unmasked by altering tissue preparation methods.

Standard tissue preparation for light and scanning electron microscopy (SEM) uses ethanol as a dehydrating agent but that can also dissolve cholesterol crystals (CC) leaving behind empty tissue imprints or "clefts". Cholesterol crystals may contribute to plaque rupture by their sharp tips that can tear membranes and trigger inflammation. Therefore, use of ethanol in tissue processing can mask the pathological role of CC. Here we evaluated the amount of cholesterol dissolved from CC with single and complete series of standard graded ethanol concentrations (25-100%) used in tissue preparation. Also, solubility of CC in ethanol at physiological levels was measured. Furthermore, we compared the effect of ethanol on CC in fresh human atherosclerotic plaques to matched segments dehydrated using vacuum (-1 atm, 12h). Tissue crystal density ranging from 0 to +3 was measured semi-quantitatively by SEM. For CC exposed to 25% and 100% ethanol for 10 min each, 0.38% and 95% of CC were dissolved respectively. Also, increase in CC solubility was significant at physiological levels of ethanol (0.16%) compared to water (43.4 ± 18.0 ng/mL vs. 30.9 ± 13.9 ng/mL; p < 0.05). We speculate that this could represent a potential mechanism of cardio-protective effects of alcohol consumption. In atherosclerotic plaques, CC density was lower in ethanol vs. saline treatment (+1.2 vs. +2.8; P < 0.01) with visible dissolving noted by SEM. Ethanol has been used for centuries in tissue preparation for microscopy. Here we demonstrate how current tissue preparation methods greatly alter histological findings with SEM by masking the potential mechanism of plaque rupture.