Papers by Keyword: Blood

Abstract: Zinc is one of the important material in human blood because of its effect in defensive system work for properly and it plays an important role in growth, wound healing Medically zinc concentration effect directly in skin health so it's important to make a sensor for discover zinc and its concentration change in human blood for each of male and female. Optical fibers are used as a sensor for detecting zinc and its concentration by transmitted laser signal through the optical fiber by using different types (single mode fiber SMF, photonic crystal fiber PCF) by studying the results of output laser the detection can be seen for zinc concentration change, the design of small PCF which the same LMA_10 but smaller in its radius of core and cladding even the distance between cores. The smallest PCF size has the best detection for all zinc concentration change in blood all that was done by comsol Multiphysics 5.4 simulation program

Abstract: In the recent years, blood flow through an aorta has been the main focus of many investigators. It shows particular interest in analyzing human aortic stiffness and blood flow behavior. Mainly, an unsteady state is applied for incompressible fluid, which is assumed to be newtonian. Artery is considered an elastic tube and the wall boundaries are isotropic. The analytical modeling of blood involves adopting an asymptotic approach according to a small aspect radio, which is inversely proportional to Reynolds number. The wall has been assumed a thin shell, which generates a small axisymmetric vibration. The mathematical model of the wall is developed using the thin shell theory based on geodesic curvature parameter. In the end, the analytical results simulation is applied to have better understanding of the effects of blood flow behavior over the elasticity aortic wall properties.

Abstract: Magnesium (Mg) is an attractive biomaterial due to its desirable biodegradable and mechanical properties. In this study, we compared the degradation behavior of Mg and a new Mg alloy incubated in both whole blood and platelet rich plasma (PRP) for two hours under standard cell culture conditions. To avoid settling of red blood cells, tubes with whole blood were under constant rotation during the incubation. Post-incubation solutions were collected, centrifuged, and analyzed for pH and Mg ion concentration. Mg and Mg alloy samples were fixed with a 3% glutaraldehyde solution, dehydrated using an ethanol series, critical point dried, sputter coated, and imaged with a field emission scanning electron microscope. Analysis of the post-incubation solutions showed PRP had greater concentrations of Mg ions and higher pH values when compared with whole blood. This indicated that the Mg and Mg alloy degraded faster when incubated in PRP than in whole blood. When comparing the surface of the materials after incubation with whole blood and PRP, the surfaces of Mg and Mg alloy that was incubated in PRP had larger cracks and grain boundaries than the samples incubated in whole blood. Additionally, more particulate microstructures were observed on the samples incubated in PRP as opposed to whole blood. Further studies are still needed to elucidate the differences in degradation of Mg alloys in whole blood and PRP.

Abstract: Dielectric properties of rat blood is measured in frequency range of 10kHz-10MHz during its coagulation process, excluding the impaction factor of temperature via measuring at 37±2°C, the results reflect the changes of relative permittivity of rat blood after it leaves the body to half an hour. Experimental results show that dielectric properties of rat blood in the coagulation process show very different characteristics in different frequencies, mechanisms of our measurements are also analyzed theoretically. The findings should provide valuable information of biochemical reaction within blood during the process of coagulation, and also provide insight into assessment of electromagnetic field exposure for human body.

Abstract: The strongly swirling turbulent flow in the internal flow field of a high-speed spiral blood pump(HSBP), is one of important factors leading to the fragmentation of the red blood cell(RBC) and the hemolysis. The study on the turbulent injure principle of blood in the HSBP is carried out by using the theory of waterpower rotated flow field and the hemorheology. The numerical equation of the strongly swirling turbulent flow field is proposed. The largest stable diameter of red blood cells in the turbulent flow field is analyzed. The determinant gist on the red blood cell turbulent fragmentation is obtained. The results indicate that in the HSMP, when turbulent flow is more powerful, shear stress is weaker, the vortex mass with energy in flow field may cause serious turbulent fragmentation because of the diameter which is smaller than the RBC’s. The RBC’s turbulent breakage will occur when the Weber value is larger than 12.

Abstract: Temperature is known to affect both the structural and functional properties of proteins in ectothermic animals like fish. Habitat temperature can lead to oxidative stress and influence the metabolic rates of enzymes in fish. In the current study, juvenile Chinese sturgeon (Acipenser sinensis), an anadromous and threatened species that lives only in the Yangtze River, were cultured under laboratory conditions for 66 days at 15, 20, 25, and 30 °C. We then studied the effects of temperature on the oxidative stress biomarkers in juvenile Chinese sturgeon. We found the activity of lysozyme (LSZ) reached its maximum at 25 °C (30.1 ± 1.2 μg/mL), while it reached its minimum at 15 °C (13.1 ± 3.3 μg/mL). In addition, the activity of xanthine oxidase (XOD) reached its maximum at 30 °C (15.20 ± 3.50), while it reached its minimum at 25 °C (12.01 ± 1.66 U/L). Furthermore, both the ability of inhibiting hydroxyl radicals (AIHR) and total antioxidative capacity (T-AOC) were increased at first and subsequently decreased with increasing temperatures, and both reached their maximum at 20 °C (1344.9 ± 349.2 U/mL and 9.54 ± 0.36 U/mL, respectively). Both AIHR and T-AOC were significantly higher at 20 °C than their corresponding levels at 25 °C and 30 °C. These results indicate that the temperature stress was higher at 15 °C and 30 °C for juvenile Chinese sturgeon. Based on the exhibited levels of LSZ, XOD, AIHR, and T-AOC in fish, we conclude the temperature range of 20−25 °C caused the least stress on the fish, and should be considered as the appropriate growth temperature for juvenile Chinese sturgeon.

Abstract: A new system for determination of trace mercury based on separation and preconcentration with porous nano-barium-strontium titanate microspheres (PBSTM) prior to its determination by a hydride generation-atomic absorption spectrometry (HG-AAS) was propounded. The optimum experimental parameters for preconcentration of mercury, such as pH of the sample, contact time, sample volume, eluent and interfering ions, have been studied. The result showed that mercury could be quantitatively retained by PBSTM in the pH range of 4-8, the shaking time was 10 min, and the amount adsorbed was 12.2 mg·g^-1. The mercury adsorbed on the sorbent could be eluated completely with 2 mol·L^-1 HNO₃. The detection limit of this method for mercury was 6.3 ng·L^-1 with an enrichment factor of 60. The method has been applied for the determination of trace amounts of mercury in whole blood and urine with satisfactory results.

Abstract: Nitric oxide (NO) produced in the endothelial cells and other tissues has been known to play a range of physiological roles including vasodilation. Thus, direct in vivo measurement of NO is of great importance for clarification of physiological roles of NO and development of therapeutics using NO. It has long been assumed that NO is readily oxidized in blood and cannot be detected; however, some recent reports demonstrated much longer half-life of NO in the blood stream in vivo. Recently, we reported the basic performance of an NO sensor which is applicable to in vivo measurement. This sensor can detect NO in the blood stream in an anesthetized rat and some biological samples including a dialysis solution. In these studies we found that NO itself showed dynamic changes different from these of oxidative products of NO (nitrite and nitrate) that are conventionally used as indices of NO level. We have also developed a catheter-type NO sensor and demonstrated validity of the sensor for in vivo measurement of NO in the aorta and coronary sinus of anesthetized dogs and rabbits. Both endothelium-dependent and -independent NO productions could be detected. In conclusion, the NO sensor and the catheter-type NO sensor are applicable to direct measurement of NO in biological samples even in vivo and will contribute to clarification of physiological roles of NO.

Abstract: A brief description of the uses and clinical applications of synthetic cyanoacrylate polymer adhesive/glues that have been cleared and/or approved as medical devices by FDA since the Medical Device Amendments of 1976 were enacted. This includes cyanoacrylate Class I devices (Exempt and not Exempt devices), Class II cyanoacrylate devices such as Dental Cements and Orthodontic Bracket Adhesives, and Class III (PMA) devices such as Dermabond™, Indermil™ Tissue Adhesive, and Trufill® n-Butyl Cyanoacrylate Embolic Agent. By citing an example of recently FDA approved Class III (PMA) devices in the Cyanoacrylate technology, the author provides a brief discussion of the FDA approval process of medical devices. It includes the FDA issues regarding the published guidance document for "Cyanoacrylate Topical Tissue Adhesives" that will provide guidance to regulatory personnel and manufacturers in the preparation of IDE applications and in the development of valid scientific evidence to support PMA applications for cyanocrylate tissue adhesives intended for topical approximation of skin and others. Also, the author provides a short regulatory description of US FDA; under what laws its operates, how FDA evaluates new devices for marketing, and how the device regulatory system works, for example, Class I, Class II, and Class III cyanoacrylate medical devices.

Abstract: Self-assembled niobium oxide microcones produced by potentiostatic anodization with varied NaF content (between 100 and 250 mg) in an HF electrolyte are shown to nucleate mineral when immersed in supersaturated solutions emulating mineral content in saliva and blood. The most extensive mineral coverage in 100 mL of 2.5 wt. % HF electrolyte occurs when NaF content is about 100 mg with substantial mineral formation occurring within 24 hours. Higher salt content apparently alters the conditions favoring mineral nucleation by generating smaller nucleation centers that ultimately diminish the extent of mineral coverage. Additionally, nucleation kinetics and morphological contrasts between mineral formed from saliva and blood is briefly discussed in terms of the relative degree of supersaturation with respect to hydroxyapatite. Finally, we show that the integrity of the microcone shape is not critical for mineral nucleation, an observation that builds on our prior hypothesis by promoting the importance of self-assembly and crystal formation. Based on these results, we demonstrate the influence of NaF and stress the role of the self-organization process in producing effective mineral nucleation sites.