The development and progression of atherosclerosis and thrombosis are closely related to changes of hemodynamics parameters. Ultrasonic pulse wave Doppler technique is normally used for noninvasively blood flow imaging. However, this technique only provides one-dimensional velocity and depends on the angle between the ultrasound beam and the local velocity vector. In this study, ultrasonic particle image velocimetry method was used to assess whole field hemodynamic changes in normal blood vessels. By using the polynomial fitting method, we investigated the velocity gradient and assessed the shear in different blood flow velocity of 10 healthy rats. It was found that using four polynomial fitting could result in optimal measurement results. The results obtained by ultrasonic particle image velocimetry accorded with the results obtained using Doppler technique. The statistical average of cyclical vessel wall shear stress was positively related to the locational mean velocity. It is proven that ultrasonic particle image velocimetry method could be used to assess directly the real-time whole field hemodynamic changes in blood vessels and was non-invasively, and should be a good prosperous technique for monitoring complex blood flow in stenotic arteries.
As drug carriers, magnetic nanoparticles can specifically bind to tumors and have the potential for targeted therapy. It is of great significance to explore non-invasive imaging methods that can detect the distribution of magnetic nanoparticles. Based on the mechanism that magnetic nanoparticles can generate ultrasonic waves through the pulsed magnetic field excitation, the sound pressure wave equation containing the concentration information of magnetic nanoparticles was derived. Using the finite element method and the analytical solution, the consistent transient pulsed magnetic field was obtained. A three-dimensional simulation model was constructed for the coupling calculation of electromagnetic field and sound field. The simulation results verified that the sound pressure waveform at the detection point reflected the position of magnetic nanoparticles in biological tissue. Using the sound pressure data detected by the ultrasonic transducer, the B-scan imaging of the magnetic nanoparticles was achieved. The maximum error of the target area position was 1.56%, and the magnetic nanoparticles regions with different concentrations were distinguished by comparing the amplitude of the boundary signals in the image. Studies in this paper indicate that B-scan imaging can quickly and accurately obtain the dimensional and positional information of the target region and is expected to be used for the detection of magnetic nanoparticles in targeted therapy.
This paper provides a brief overview of the current research activities which focused on the bio-application of gold magnetic nanocomposite particles. By combining the magnetic characteristics of the iron oxide core with the unique features of nano-gold particles such as targeting by surface modification and optical properties, such composite nanoparticles have a wide range of applications in cancer hyperthermia, CT and MRI imaging, bio-separation, biosensors, gene diagnosis, drug targeting and many other biomedical fields.
Objective To determine the best matching concentration of carbon nanoparticles suspension injection adsorb epirubicin by measuring the combination ratio of carbon nanoparticles suspension injection combined with epirubicin under different matching conditions. And then, to prove the adsorbability of carbon nanoparticles suspension injection adsorb epirubicin in vitro. Methods Firstly, epirubicin-carbon suspension of different concentrations will be prepared. The second, high performance liquid chromatography mass spectrometry（LC-MS） was used to assay the concentration of free epirubicin, and calculate the content of epirubicin that was combinated with carbon nanoparticles suspension injection. The difference of the ratio of carbon nanoparticles suspension injection combined with epirubicin under different matching conditions will be compared in the end. Results The combination ratio of carbon nanoparticles suspension injection combined with epirubicin solution of 5, 10, and 15 mg/ml were 85.6%, 85.7%, and 31.8%, respectively. Conclusions The adsorbability of carbon nanoparticles suspension injection adsorb epirubicin is favourable in vitro. Best matching concentration of carbon nanoparticles suspension injection adsorb epirubicin may be epirubicin solution of 5-10 mg/ml.
ObjectiveTo study the effect of titanium particles on the proliferation, differentiation, and cytomorphology of osteoblasts, and to explore the possible internal relations and mechanism. MethodsCalvarial osteoblasts were separated from 10 newborn Sprague Dawley rats by repeated enzyme digestion, and were cultured in vitro. The cells were identified by alkaline phosphatase (ALP) staining and alizarin red staining. The cells at passage 3 were cultured with titanium particles culture medium at concentrations of 0.01, 0.05, 0.1, 0.5, and 1 mg/mL (0.01, 0.05, 0.1, 0.5, and 1 mg/mL groups). The absorbance (A) values were detected by cell counting kit 8 at 7 days after cultured to compare the effect of titanium particles at different concentrations on proliferation, and median lethal concentration was screened out. The expression of collagen type I was detected by ELISA to observe the effect of titanium particles on differentiation. The osteoblasts co-cultured with titanium particles of median lethal concentration (experimental group) for 7 days, and double fluorescence staining with FITC-phalloidine and propidium iodide was performed. The cytomorphology variation of osteoblasts after swallowing titanium particles was observed under laser scanning confocal microscope. The osteoblasts at passage 3 cultured with culture medium without titanium particles served as control group. ResultsThe cultured cells were identified as osteoblasts by ALP staining and alizarin red staining. Different concentrations of titanium particles could inhibit osteoblasts proliferation and differentiation in varying degrees, showing significant difference when compared with the control group at 7 days after culture (P<0.05). The cell proliferation and differentiation were decreased with increased titanium particles concentration; significant differences were found between the other groups (P<0.05) except 0.01 and 0.05 mg/mL groups (P>0.05). The median lethal concentration of titanium particles was 0.5 mg/mL. Laser scanning confocal microscope showed cellular shrinking, microfilaments distortion, pseudopodia contraction of osteoblasts that swallowed titanium particles in the experimental group. ConclusionTitanium particles can inhibit proliferation and differentiation of osteoblasts. The effect may be related to variation of cytomorphology after swallowing titanium particles.
Objective To verify tissue factor (TF)-bearing microparticle (TF-MP) could be released from Kupffer cells (KCs) stimulated by lipopolysaccharide (LPS) and TF controlled by Toll-like receptor 4 (TLR4) could induce acute pancreatitis. Methods After the acute pancreatitis model completed, the wild type C57/BL6 mouse (WT group) and the TLR4-/- mouse (TLR4-/- group) received intraperitioneal injections of 10 mg/kg LPS. The degree of pathological lesion and the TF expression were detected in the pancreas tissue. The TF and TLR4 protein and mRNA expressions in the KCs were detected at 6, 12, and 24 h after the last injection of LPS. The survival rates were campared in these estabilshed acute pancreatitis model mice. The TF and TLR4 protein and mRNA expressions in the KCs stimulated with LPS (300 μg/L) were also detected at 0, 15, 30, 60, and 120 min. The TF and TF-MP levels were detected in the supernatants of the KCs at these time point. Results The injury of the pancreas in the TLR4-/- group was slighter than that in the WT group. The TF proteins in the liver and pancreas tissues of the TLR4-/- group were significantly lower than those of the WT group (P<0.05). The survival rate of the TLR4-/- group was significantly higher than that of the WT group under the situation of the acute pancreatitis (P<0.05). The TLR4 and TF protien and mRNA expressions of the KCs were significantly decreased in the TLR4-/- group as compared with the WT group at 30, 60, and 120 min (P<0.05). The levels of TF and TF-MP in the supernatant of the TLR4-/- group were significantly lower than those of the WT group at 30, 60, and 120 min (P<0.05). Conclusion Acute pancretitis can be induced by TF and TF-MP expressions in KCs which could be regulated by TLR4 pathway.
ObjectiveThe antifriction and antiwear effects of gelatin nanoparticles (GLN-NP) on artificial joint materials in bionic joint lubricant were investigated to provide a theoretical basis for the development of new bionic joint lubricant. MethodsGLN-NP was prepared by cross-linking collagen acid (type A) gelatin with glutaraldehyde by acetone method, and the particle size and stability of GLN-NP were characterized. The biomimetic joint lubricants with different concentrations were prepared by mixing 5, 15, and 30 mg/mL GLN-NP with 15 and 30 mg/mL hyaluronic acid (HA), respectively. The friction reduction and antiwear effects of the biomimetic joint lubricants on zirconia ceramics were investigated on a tribometer. The cytotoxicity of each component of bionic joint lubricant on RAW264.7 mouse macrophages was evaluated by MTT assay. ResultsThe particle size of GLN-NP was about 139 nm, and the particle size distribution index was 0.17, showing a single peak, indicating that the particle size of GLN-NP was uniform. In complete culture medium, pH7.4 PBS, and deionized water at simulated body temperature, the particle size of GLN-NP did not change more than 10 nm with time, indicating that GLN-NP had good dispersion stability and did not aggregate. Compared with 15 mg/mL HA, 30 mg/mL HA, and normal saline, the friction coefficient, wear scar depth, width, and wear volume were significantly reduced by adding different concentrations of GLN-NP (P<0.05); there was no significant difference between different concentrations of GLN-NP (P>0.05). Biocompatibility test showed that the cell survival rate of GLN-NP, HA, and HA+GLN-NP solution decreased slightly with the increase of concentration, but the cell survival rate was more than 90%, and there was no significant difference between groups (P>0.05). ConclusionThe bionic joint fluid containing GLN-NP has good antifriction and antiwear effect. Among them, GLN-NP saline solution without HA has the best antifriction and antiwear effect.
Objective To explore the change of particles of Shuanghuanglian Injection (SHLI) admixed with different infusion solutions, and provide a reference for selecting rational menstruum. Methods A comprehensive literature search was executed to collect all the studies on the compatibility of SHLI with different infusion solutions. The reporting quality of the included studies was assessed; particles-related data were extracted and analyzed systematically. Results A total of 338 studies were identified, and 24 studies were included after screening. The quality of the included studies were poor and had heterogeneous outcomes. Generally, the particles of mixture increased dramatically, and there were significant differences among different pharmaceuticals, drug batches and infusion solutions. The pH of solvent had a greater impact on the particles, and the concentration and storage time of prepared liquor were other important factors. The particles of SHLI admixed with Normal Saline were less than 5%, 10% glucose injection and other solvents. Conclusion The particles of SHLI admixed with Normal Saline are the fewest, and commonly can be the preferred solvent. Factors on rational drug use are worthy of further studies; and more attention is needed for the scientificalness of study design.
The hydroxyapatite particles were used to repair 23 cases of depressed deformities of face. The patients were follwed up for 3 to 8 months and the short termresults were satisfactory. The operative procedure was briefly introduced. The advantages and attentions relevant to the operation were discussed.
The study of viruses traditionally focused on their roles as infectious agents and as tools for understanding cell biology. Recently, however, with the development of structural biology, viruses have now been receiving particular attention in nanotechnology. By chemical methods or by gene modification, viruses have been functionalized as potential building blocks for several applications, such as drug/gene delivery vehicles, advanced vaccine vehicles, and special inorganic or organic nanomaterials. Here we highlight some of the recent progresses in the medical applications of viruses.