Design and Hemocompatibility Analysis of a Double-Suction Injection Suspension Blood Pump Using Computational Fluid Dynamics Methods.

The blood pump has become a possible solution to heart diseases. For the prevention of device failure and hemocompatibility problems, a rotary pump with suspended bearing is a preferred solution. In our previous work, a novel injection suspension method has been introduced to levitate the rotor. The suspension method is totally passive. This study aims to apply this suspension method to a double-suction pump, and the property of the pump was investigated using computational fluid dynamics (CFD) methods. The flow field of the pump is simulated based on the SST k-ω turbulent model. The characteristic curves of the pump were calculated. At the nominal working point of 5 L/min, 100 mm Hg, the suspension force acting on the rotor was detected, which could reach 0.46 N with a gap of 150 µm. We compared the pump with a previously developed single-suction injection pump to evaluate the blood compatibility of the double-suction design. The average scalar shear stress values were 3.13 Pa for the double-suction pump and 7.10 Pa for the single-suction pump. Larger volumes in the single-suction pump were exposed to shear stresses higher than 10 Pa. Thresholds for the von Willebrand factor cleavage, platelet activation, and hemolysis were defined to be 9 Pa, 50 Pa, and 150 Pa, respectively. The volume fractions for the double-suction pump are lower for all thresholds. The normalized index of hemolysis (NIH) values for the two pumps were calculated to be 0.008 g/100 L and 0.016 g/100 L. Results proved that the double-suction pump has a better hemocompatibility compared with the single-suction pump.

Ocular delivery of cyanidin-3-glycoside in liposomes and its prevention of selenite-induced oxidative stress.

CONTEXT: Cataracts have become the leading cause of blindness around the world, which is mainly mediated by oxidative stress. OBJECTIVE: N-trimethyl chitosan (TMC)-coated liposomes of cyanidin-3-glycoside (C3G) (C3G-TCL) were prepared to attenuate oxidative stress induced by selenite sodium in rats. MATERIALS AND METHODS: C3G-TCL were prepared by reverse-phase evaporation method and then coated with self-synthesized TMC. The physicochemical properties were determined. A gamma-scintigraphy study was employed to evaluate the precorneal elimination of the radioactive preparations. The transcorneal visualization for fluorescence-labeled samples was determined by confocal laser scanning microscopy (CLSM). The in vivo anti-oxidative study using C3G-TCL was carried out in rats with selenite-induced cataracts by topical administration. RESULTS: The sphere-like morphological characterization of the vesicles was confirmed by TEM, with a size of 158.3 ± 2.8 nm and a zeta potential of 31.7 mV. The encapsulation efficiency was (53.7 ± 0.2) % as measured by ultrafiltration. C3G-TCL showed a 3.3-fold increment in precorneal residence time when compared with that of the (99m)Tc-solution. A TMC coating enhanced the transepithelial transport of liposomes to a depth of 40-µm in the cornea. Moreover, C3G-TCL could significantly elevate the activity of superoxide dismutase and catalase in lens and also show a considerable reversal of reduced glutathione activity. The lipid peroxidation in lens was strongly prevented when compared with that of groups treated with uncoated C3G-loaded liposomes. DISCUSSION AND CONCLUSION: The coating material TMC for liposomes helps improve the anti-oxidative effect of C3G in vivo through prolonged residence time on the cornea and improved permeability in the corneal epithelium.

[Correlations between micromeritic properties of mixing powders of danshen extract and formability of their pellets].

It was difficult to prepare traditional Chinese medicine pellets due to the adverse characteristics of the herbal extract. In this study, Danshen extract (DS) powder mixed with different proportions of microcrystalline cellulose (MCC), lactose and starch were made into pellets by extrusion-spheronization. Particle size, span, bulk density, tapping density, compressibility, Hausner ratio and angle of repose were used to evaluate the micromeritic properties of mixing powders. Feret diameter, aspect ratio, yield, density and friability were used to evaluate the properties of the pellets. The correlations between micromeritic properties of raw material powders and the formability of their pellets were analyzed by cluster analysis, principal component analysis and partial least squares regression analysis. As a result, the particle size of the powders was negatively correlated with the size, density, yield, and was positively correlated with the friability of their pellets. The span, density, compressibility and angle of repose of the powders were positively correlated with the size, density, yield, and were negatively correlated with the friability of their pellets. So there were certain correlations between the micromeritic properties of raw material powders and the properties of their pellets prepared by extrusion-spheronization. This research provided a foundation for the technology and method of traditional Chinese medicine extract pellets.

Extracellular matrix-coating pedicle screws conduct and induce osteogenesis.

BACKGROUND: The purpose of the present study was to study the effects of the extracellular matrix-coating pedicle screws on the conduction and induction of bone formation in young sheep. METHODS: Pedicle screws [coated with collagen/chondroitin sulfate (coll/CS), hydroxyapatite (HA), and coll/CS/HA or uncoated] were randomly implanted into the L2-L5 pedicles of sheep. In the first stage, a static experiment was performed. In the second stage, a loading test was performed by implanting connecting rods. After 3 months, the lumbar vertebrae with the screws were removed and examined by micro-CT, histological, and biomechanical analyses. RESULTS: Under non-loading conditions, there is bone formation around the surfaces of coated screws. Bone formation on the surface of the coll/CS/HA coating of pedicle screws was the highest. In terms of the trabecular bone morphology parameters of the region of interest around the surface of the pedicle screws, those associated with coll/CS/HA coatings were highest under non-loading conditions, the pullout strength of the coll-/CS-/HA-coated screws was the highest and that of the uncoated screws was minimal. Under loading conditions, the maximum pullout strength of each group of pedicle screws was less than that of the pedicle screws in the non-loading state. CONCLUSIONS: Under non-loading conditions, the organic and inorganic components of the titanium pedicle screw coatings can conduct or induce bone formation around the surface of the screws. The ability of the coll/CS/HA coating to induce bone formation was the strongest. Under loading conditions, a large amount of connective tissue formed around the surface of the screws in each group.

Quantitation of Enterovirus A71 Empty and Full Particles by Sedimentation Velocity Analytical Ultracentrifugation.

The enterovirus A71 (EV71) inactivated vaccine is an effective intervention to control the spread of the virus and prevent EV71-associated hand, foot, and mouth disease (HFMD). It is widely administered to infants and children in China. The empty particles (EPs) and full particles (FPs) generated during production have different antigenic and immunogenic properties. However, the antigen detection methods currently used were established without considering the differences in antigenicity between EPs and FPs. There is also a lack of other effective analytical methods for detecting the different particle forms, which hinders the consistency between batches of products. In this study, we analyzed the application of sedimentation velocity analytical ultracentrifugation (SV-AUC) in characterizing the EPs and FPs of EV71. Our results showed that the proportions of the two forms could be quantified simultaneously by SV-AUC. We also determined the repeatability and accuracy of this method and found that both parameters were satisfactory. We assessed SV-AUC for bulk vaccine quality control, and our findings indicated that SV-AUC can be used effectively to analyze the percentage of EPs and FPs and monitor the consistency of the process to ensure the quality of the vaccine.

[Influence of Polystyrene Microplastics on the Formation and Structural Change of Pseudomonas aeruginosa Biofilm].

Microplastic pollution in the water environment is becoming increasingly serious, impacting the growth and development of aquatic organisms. There are limited studies on the mechanisms of microplastic effects on biofilm formation. Therefore, in this study, the effects of polystyrene microplastics (PS-MPs) were investigated on the biofilm formation and development of Pseudomonas aeruginosa. Different concentrations and particle sizes of PS-MPs were selected for exposure tests to explore the effects on biofilm biomass, oxidative stress levels, biofilm structure, and population sensing system. The results showed that PS-MPs induced severe oxidative stress and inhibited biofilm formation and development, and the smaller the particle size, the stronger the inhibitory effect was. The inhibition effect was 0.1 µm>0.5 µm≈1 µm>5 µm. PS-MPs caused severe physical damage through contact with bacteria. The thickness of the biofilm was significantly reduced, damaging the structural stability. The bacteria in the biofilm secreted extracellular polymers to resist the stress of PS-MPs. Meanwhile, PS-MPs interfered with the QS system of P. aeruginosa; down-regulated the expression levels of key genes lasI, lasR, rhlI, and rhlR; inhibited the synthesis and secretion of signal molecules and related virulence factors; and ultimately affected the formation and structural stability of biofilms.

Regenerative Efficacy of Supercritical Carbon Dioxide-Derived Bone Graft Putty in Rabbit Bone Defect Model.

Bone defects can arise from numerous reasons, such as aging, tumor, trauma, infection, surgery, and congenital diseases. Bone grafts are commonly used as a substitute to fill the void and regenerate the defect. Due to its clean and green technology, the supercritical carbon dioxide (SCCO2) extraction aided the production of bone grafts is a recent trend. The SCCO2-derived bone graft has osteoconductive and osteoinductive properties along with excellent biocompatible, nontoxic, bioabsorbable, osteoconductive, and good mechanical properties; however, clinical usage during surgery is time-consuming. Therefore, we produced a putty material combining bone graft powder and acellular dermal matrix (ADM) powder and tested its regenerative efficacy in the critical defect in the rabbit model. The putty was found to retain the tubular structure. In addition, the putty depicted excellent stickiness and cohesiveness in both saline and blood medium. The bone regeneration of bone graft and putty was similar; both had excellent bone healing and regeneration of critical defects as evaluated by the X-ray, microtomography, hematoxylin-eosin, Masson trichrome, and alizarin red staining. Putty contains a less washout rate, good mechanical strength, and biocompatibility. In conclusion, the SCCO2-derived moldable putty could be a promising easy-to-use alternative for bone grafts at present which might have real-world usage in orthopedics as a potential bone void filler and dental socket preservation.

Synergic Thermo- and pH-Sensitive Hybrid Microgels Loaded with Fluorescent Dyes and Ultrasmall Gold Nanoparticles for Photoacoustic Imaging and Photothermal Therapy.

Smart microgels (µGels) made of polymeric particles doped with inorganic nanoparticles have emerged recently as promising multifunctional materials for nanomedicine applications. However, the synthesis of these hybrid materials is still a challenging task with the necessity to control several features, such as particle sizes and doping levels, in order to tailor their final properties in relation to the targeted application. We report herein an innovative modular strategy to achieve the rational design of well-defined and densely filled hybrid particles. It is based on the assembly of the different building blocks, i.e., µGels, dyes, and small gold nanoparticles (<4 nm), and the tuning of nanoparticle loading within the polymer matrix through successive incubation steps. The characterization of the final hybrid networks using UV-vis absorption, fluorescence, transmission electron microscopy, dynamic light scattering, and small-angle X-ray scattering revealed that they uniquely combine the properties of hydrogel particles, including high loading capacity and stimuli-responsive behavior, the photoluminescent properties of dyes (rhodamine 6G, methylene blue and cyanine 7.5), and the features of gold nanoparticle assembly. Interestingly, in response to pH and temperature stimuli, the smart hybrid µGels can shrink, leading to the aggregation of the gold nanoparticles trapped inside the polymer matrix. This stimuli-responsive behavior results in plasmon band broadening and red shift toward the near-infrared region (NIR), opening promising prospects in biomedical science. Particularly, the potential of these smart hybrid nanoplatforms for photoactivated hyperthermia, photoacoustic imaging, cellular internalization, intracellular imaging, and photothermal therapy was assessed, demonstrating well controlled multimodal opportunities for theranostics.

Synthesis, characterization and osteoconductivity properties of bone fillers based on alendronate-loaded poly(ε-caprolactone)/hydroxyapatite microspheres.

A superior drug controlled release system capable of achieving efficient osteogenesis is in imperative demand because of limited bone substitute tissue for the treatment of bone defect. In the present study, we investigated the potential of using poly(ε-caprolactone)-hydroxyapatite (PCL-HA) composite microspheres as an injectable bone repair vehicle by controlled release of alendronate (AL), a medicine that belongs to the bisphosphonates family. The PCL/HA-AL microspheres were prepared with solid/oil/water emulsion technique, which included two processes: (1) AL was loaded on the hydroxyapatite nanoparticles; (2) the HA-AL complex was built in the PCL matrix. The spherical PCL/HA-AL microspheres were characterized with its significantly improved encapsulation efficiency of hydrophilic AL and better sustained release. Human bone mesenchymal stem cells (hMSCs) were cultured on the surface of these microspheres and exhibited high proliferative profile. Specifically, in osteogenic medium, hMSCs on the surface of PCL/HA-AL microspheres displayed superior osteogenic differentiation which was verified by alkaline phosphatase activity assay. In conclusion, by presenting strong osteogenic commitment of hMSCs in vitro, the PCL/HA-AL microspheres have the potential to be used as an injectable vehicle for local therapy of bone defect.

Nanomedicine to advance the treatment of bacteria-induced acute lung injury.

Bacteria-induced acute lung injury (ALI) is associated with a high mortality rate due to the lack of an effective treatment. Patients often rely on supportive care such as low tidal volume ventilation to alleviate the symptoms. Nanomedicine has recently received much attention owing to its premium benefits of delivering drugs in a sustainable and controllable manner while minimizing the potential side effects. It can effectively improve the prognosis of bacteria-induced ALI through targeted delivery of drugs, regulation of multiple inflammatory pathways, and combating antibiotic resistance. Hence, in this review, we first discuss the pathogenesis of ALI and its potential therapeutics. In particular, the state-of-the-art nanomedicines for the treatment of bacteria-induced ALI are highlighted, including their administration routes, in vivo distribution, and clearance. Furthermore, the available bacteria-induced ALI animal models are also summarized. In the end, future perspectives of nanomedicine for ALI treatment are proposed.

[Kinetic spectrophotometric study on hemolytic process of polysorbate 80].

To establish kinetic assay method for the analysis of hemolysis and to investigate dynamic hemolytic process of polysorbate 80. The UV-VIS spectrum of heme changes when hemoglobin is released continuously during the hemolytic process. Therefore, dynamic hemolytic curve was determined as a new way to characterize the kinetic process of interaction between polysorbate 80 and red blood cells. The effect of polysorbate 80 on blood cells could be perfectly investigated by the hemolytic dynamics. Dynamic hemolytic parameters of polysorbate 80 were calculated according to the hemolytic curves. The constants of hemolytic rate and maximum hemolytic rate of polysorbate 80 had fine linear relationships at the range of 1-20 mg x mL(-1) and 5-20 mg x mL(-1), respectively. In comparison with the present official method such as macroscopic observation and static spectrophotometric methods, kinetic spectrophotometry has the advantages of real time, on-line determination, sensitive, objective, good reproducibility and 2-dimensional information acquired. Therefore, as a biological technique, kinetic spectrophotometry could be applied to evaluate the quality of polysorbate 80 and to screen other solubilizing excipients.

Gene expression analysis of primary gingival cancer by whole exome sequencing in thirteen Chinese patients.

OBJECTIVES: Early diagnosis of and markers for gingival oral squamous cell carcinoma (OSCC) is important for effective treatment. METHODS: The current study performed a whole exome sequencing of gingival OSCC tissues in thirteen Chinese patients to explore exonic mutants. RESULTS: Eighty-five genes emerged as mutants in patients with primary gingival OSCC. CCL4L1 presented a G>A transversion at chr17 17q12, position 36212480, exon 3. KDM5B presented a T>TA insertion at chr1 1q32.1, position 202766506, exon 6. ANKRD36C presented a C>G transition at chr2 2q11.1, position 95945175, exon 18. CONCLUSION: These three mutants might be new markers of gingival OSCC. The finding may provide new targets to diagnose and treat gingival OSCC.

Application of shape memory alloy pressure-controlled vascular clamp for atraumatic vessel occlusion.

BACKGROUND: To realize atraumatic vessel occlusion, a new hemostatic clamp using superelastic shape memory alloy (SMA) as a pressure control limiter has been proposed. It was designed taking advantage of a unique mechanical property of SMA. The ability to control pressure with the newly designed SMA clamp was investigated. The traumatic effect on vessel walls was evaluated in order to confirm the SMA clamp's biological effect of protecting vessels from damage. METHODS: Twenty-four pig thoracic aortas were divided into four groups: SMA group 1 (0.3mm diameter SMA wire used), SMA group 2 (0.4mm diameter SMA wire used), base model group (hemostatic clamp of Mimura type), and a control group. The biomechanical interaction between the pressure-controlled clamp and animal aortas was evaluated with a micropressure analyzing system. The atraumatic effect of the SMA clamp was examined on pig thoracic aortas in vitro and compared with that of its base model. The morphological injury of each vessel was evaluated after being clamped for 15 min. RESULTS: Pressure saturation was shown in the displacement-pressure curve of the SMA clamp. In both SMA group 1 and SMA group 2, except for a slight imprint of compression in the intima, no obvious injury was observed, while in the base model group the endothelial laceration was observed when the clamp was closed to notch I. More serious injuries in the endothelial intima and media were observed when the clamp was closed to notches II and III. CONCLUSION: The effect of pressure-controlling SMA clamps on the in vitro vessel model was evaluated. Histological observation and the traumatic score proved that the safety of the clamps was improved with the new design of pressure control. This technique supplies an effective and applicable way of realizing atraumatic clamping.

3D printing of strontium-doped hydroxyapatite based composite scaffolds for repairing critical-sized rabbit calvarial defects.

In this study, strontium substituted hydroxyapatite (Sr-HAP) was synthesized using collagen type I and citrate as bi-templates and the obtained nanoparticles with high similarity to natural bone minerals were made into composite scaffolds with interconnected porous structure using a three-dimensional (3D) printing technique. A calcium deficient structure of HAP phase was caused by doping Sr which was verified by Fourier transform infrared, x-ray diffractometer, scanning electron microscopy and transmission electron microscopy. The Sr/(Sr + Ca) molar ratio in Sr-HAP nanoparticles was 5.8% estimated by EDX. Furthermore, both 3D printed scaffolds made of Sr-HAP and HAP had uniform porous structure and porosity of about 60%. Cell culturing indicated that MC3T3-E1 cells could adhere on the surface of the scaffolds and the strontium substitution could enhance cell adhesion, proliferation and alkaline phosphatase activity. The printed composite scaffolds were used to repair critical-sized rabbit calvarial defects with a diameter of 15 mm. The results showed that the Sr-HAP scaffolds had better osteogenic capability and stimulated more new bone formation within 12 weeks. It was suggested that these printed Sr-HAP composite scaffolds possessed high potential as candidates in the application of bone augmentation and regeneration.

[Changes of cementum endotoxin levels in different teeth with periodontitis treated with root conditioning].

PURPOSE: To observe the changes of endotoxin levels after different teeth with periodontitis were treated with different methods. METHODS： Six healthy premolars extracted for orthodontic reasons and 36 posterior teeth extracted due to severe periodontitis were selected. Each tooth was processed from two 4 mm×4 mm×1 mm cementum pieces 2 mm under the cementum-enamel junction, each tooth with periodontitis was numbered. Healthy teeth served as negative control group, one of the two tablets from each tooth with periodontitis was selected in the periodontitis group, which was not treated with root surface treatment. The remaining 36 teeth with periodontitis were randomly divided into 6 groups: SRP group, SRP + antimicrobial peptide A group , SRP + antimicrobial peptide B group, SRP + EDTA group, SRP + Er:YAG laser group and SRP + Nd:YAG laser group. Endotoxin concentration in each tooth was determined by chromogenic substrate limulus reagent. The endotoxin concentration in each tooth was recorded according to the serial number, and the changes of endotoxin concentration were calculated before and after treatment. SPSS17.0 software package was used to analyze the data. RESULTS: Compared with the teeth with periodontitis, endotoxin concentration decreased to varying degrees, there were significant differences in each treatment group(P<0.01). Compared with SRP group, endotoxin levels in SRP + antimicrobial peptide A group, SRP + antimicrobial peptide B group, SRP + Er:YAG laser group were significantly decreased(P<0.01). No significant difference decreased was from between SRP + EDTA group and SRP + Nd:YAG laser group(P>0.05). CONCLUSIONS: Treatment of teeth with periodontitis using different methods can decrease the level of endotoxin, and the treatment of periodontitis root surface with antimicrobial peptide A + SRP may be more effective.

Bone morphogenetic protein-2 sustained delivery by hydrogels with microspheres repairs rabbit mandibular defects.

Mandible defect is a difficult issue in dental surgery owing to limited therapeutic options. Recombinant human bone morphogenetic protein-2 (rhBMP2) is osteoinductive in bone regeneration. This article prepared chitosan/collagen hydrogels with rhBMP2-incorporated gelatin microsphere (GMs) for a sustained release of rhBMP2 to induce bone regeneration in rabbits. In experiments, mandibular defects of 8 mm in diameter and 3 mm in depth were surgically prepared on the right cheek of 27 rabbits. Either chitosan/collagen hydrogels alone, rhBMP2-incorporated hydrogels, or hydrogels with rhBMP2-incorporated GMs were implanted to the defect sites. The animals were euthanized at 2, 6, 12 weeks following surgery. In results, scanning electronic microscope images revealled spherical GMs. The complex delivery systems, hydrogels with rhBMP2-incorporated GMs, exhibited ideal release profiles in vitro. The complex delivery systems resulted in apparent new bone formation within 12 weeks, as evidenced by computed tomography and histological observations. All these results demonstrated that the chitosan/collagen hydrogels with rhBMP2-incorporated GMs had a better capacity to heal mandible defects than other two hydrogel scaffolds. Chitosan/collagen hydrogels with rhBMP2-incorporated GMs might be potential carriers of rhBMP2 for accelerating the repair of mandibular defects.

ODAM is a predictor for biomedical recurrence and inhibits the migration and invasion of prostate cancer.

Odontogenic ameloblast associated protein (ODAM) is a protein contributed to cell adhesion and has been shown to express in normal prostate tissue, but the expression and significance of ODAM in prostate cancer remain unknown. In this study, we detected the protein expressions of ODAM in 88 prostate cancer tissues with immunohistochemical staining, and found that 53 cases (60.2%) was high expression of ODAM, which was shown in the cytoplasm and paranuclear regions. Furthermore, low expression of ODAM was significantly correlated with lymph node metastasis, preoperative PSA and Gleason score, but not with mean age, follow-up duration, PSM rate and distribution of pathological T stage. Additionally, our results of multivariate analysis showed that low ODAM expression was an independent predictor of biomedical recurrence, while the positive lymph node metastasis, Gleason score, and preoperative PSA were not the independent risks for biomedical recurrence. Overexpression of ODAM did not inhibit the growth of prostate cancer cells PC3, but significant suppressed their invasion and migration with decrease of the protein levels of MMP-2. These results suggest that ODAM is a predictor for biomedical recurrence and inhibits the migration and invasion of prostate cancer.

Regulation of migration and invasion by Toll-like receptor-9 signaling network in prostate cancer.

Toll-like receptors (TLRs) play an important role in tumorigenesis and progress of prostate cancer. However, the function and mechanism of Toll-like receptor-9 (TLR9) in prostate cancer is not totally understood. Here, we found that high expression of TLR9 was associated with a higher probability of lymph node metastasis and poor prognosis. Further in vitro functional study verified that silence of TLR9 inhibited migration and invasion of PC-3 cells, indicating expression of TLR9 involving in the migration and invasion of cancer cells. The data of microarray exhibited silence of TLR9 induced 205 genes with larger than 2-fold changes in expression levels, including 164 genes down-regulated and 41 genes up-regulated. Functional Gene Ontology (GO) processes annotation demonstrated that the top three scores of molecular and cellular functions were regulation of programmed cell death, regulation of locomotion and response to calcium ion. TLR9 signaling network analysis of the migration and invasion related genes identified several genes, like matrix metallopeptidase 2 (MMP2), matrix metallopeptidase 9 (MMP9), chemokine receptor 4 (CXCR4) and interleukin 8 (IL8), formed the core interaction network based on their known biological relationships. A few genes, such as odontogenic ameloblast-associated protein (ODAM), claudin 2 (CLDN2), gap junction protein beta 1 (GJB1) and Rho-associated coiled-coil containing protein kinase 1 pseudogene 1 (ROCK1P1), so far have not been found to interact with the other genes. This study provided the foundation to discover the new molecular mechanism in signaling networks of invasion and metastasis in prostate cancer.

Functional evaluation of an artificial anal sphincter using shape memory alloys.

This article describes an implantable artificial anal sphincter using shape memory alloys and its in vivo assessment in porcine models. The new design was developed as a low invasive prosthesis with a simple structure to solve the problem of severe fecal incontinence in patients with hypoplastic sphincters or without anal sphincters and especially for ostomates. The artificial anal sphincter consists of two shape memory alloy (SMA) plates as the main functional parts to perform two basic functions when the SMA artificial sphincter is fitted around intestines (i.e., an occlusion at body temperature and an opening function on heating). Our previous assessments with short-term animal experiments revealed promising properties with the occlusion function of the device, although some complications, such as overpressure induced ischemia, heat burn, and infections, remained. This article addresses the concerns related to the practical use of the device, the power supplement to drive the actuator, and overheating protection of the device inside bodies. Results of chronic animal experiments of up to 4 weeks suggested great potential for the improved device.

Resveratrol oligomers for the prevention and treatment of cancers.

Resveratrol (3,4',5-trihydroxystilbene) is a naturally derived phytoalexin stilbene isolated from grapes and other plants, playing an important role in human health and is well known for its extensive bioactivities, such as antioxidation, anti-inflammatory, anticancer. In addition to resveratrol, scientists also pay attention to resveratrol oligomers, derivatives of resveratrol, which are characterized by the polymerization of two to eight, or even more resveratrol units, and are the largest group of oligomeric stilbenes. Resveratrol oligomers have multiple beneficial properties, of which some are superior in activity, stability, and selectivity compared with resveratrol. The complicated structures and diverse biological activities are of significant interest for drug research and development and may provide promising prospects as cancer preventive and therapeutical agents. This review presents an overview on preventive or anticancer properties of resveratrol oligomers.