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Background: The bone defects caused by different reasons led to deformity and dysfunction of human body. Considering the need for clinical application, it was essential for bone regeneration to exploit a scaffold with bioactive bone cement. In this paper, we fabricated bioactive magnesium phosphate bone cement (BMPC) at room temperature, then it was set at 37℃ and 100% humidity for 2h. Methods: The process was as follows. MgO was formed by calcining Mg2(OH)2CO3, MgO, KH2PO4 and carboxymethyl chitosan were mixed to form magnesium phosphate bone cement(MPC), then Ca(H2PO4)2 was added to neutralize alkaline product after MPC hydration to fabricate bioactive magnesium phosphate bone cement (BMPC). The influence of doped content of Ca(H2PO4)2 on the properties of bone cement was discussed. Results: The results showed that Ca(H2PO4)2 and carboxymethyl chitosan can adjust the setting time of bone cement within the scope of 8 minute and 25 minute. The compressive strength increased first and then decreased. After 48h without additional pressure, the compressive strength reached the maximum value, so it was about of 38.6 MPa. Ca(H2PO4)2 and carboxymethyl chitosan can play a synergistic role in regulating the BMPC properties. BMPC was degradable in the simulated body fluid (SBF). The results of cytotoxicity experiment and laser confocal microscopy experiment indicated that BMPC fabricated at room temperature had better biocompatibility and degradability, which was more consistent with clinical operation requirement.Conclusions: BMPC can be used as a promising orthopedic material, and it can meet with the needs for repairing bone defects.

Bone defects occurring for various reasons can lead to deformities and dysfunctions of the human body. Considering the need for clinical applications, it is essential for bone regeneration to exploit a scaffold with bioactive bone cement. In this study, we fabricated bioactive magnesium phosphate bone cement (BMPC) at room temperature; then, it was set at to °C and 100% humidity for 2 h. The process was as follows: Simulating a clinical environment, magnesium oxide (MgO) was formed by calcining basic magnesium carbonate (Mg2(OH)2CO3). MgO, potassium dihydrogen phosphate (KH2PO4) and carboxymethyl chitosan (C20H37N3O14, CMC) were mixed to form magnesium phosphate bone cement (MPC); then, monocalcium phosphate (Ca(H2PO4)2) was added to neutralize the alkaline product after MPC hydration to fabricate bioactive magnesium phosphate bone cement (BMPC). The influence of the doped content of Ca(H2PO4)2 on the properties of bone cement was discussed. The results showed that Ca(H2PO4)2 and CMC can adjust the setting time of bone cement to between 8 and 25 min. The compressive strength increased first and then decreased. After 48 h without additional pressure, the compressive strength reached the maximum value, which was about 38.6 MPa. Ca(H2PO4)2 and CMC can play a synergistic role in regulating the properties of BMPC. The BMPC was degradable in the simulated body fluid (SBF). The results of the cytotoxicity experiment and laser confocal microscopy experiment indicated that BMPC fabricated at room temperature had better biocompatibility and degradability, which was more consistent with clinical operation requirements. BMPC is a promising orthopedic material and is suitable for repairing bone defects.

Given the three-dimensional multi-level structure of natural bone and the multi-factor time-shifting effect in the healing process after bone trauma, there are plans to introduce drug-controlled release systems into the treatment of orthopedic diseases. To achieve multi-level loading and controlled release of biologically active substances, it is necessary to create synergistic behavior between biological factors, thereby improving the bone regeneration ability of artificial bone replacement materials. A naringin-loaded (NG) coating was prepared, compared with ultrasonic micro-arc oxidation (UMAO). The coating was characterized by X-ray diffraction, infrared spectroscopy, and scanning electron microscopy. The corrosion resistance of the coating was studied through the wetting angle and polarization curve. The high-performance liquid chromatography method was used to test the release of the drug. It can be seen from the experimental results that the NG coating has a larger wetting angle and better corrosion resistance. In addition, the NG coating produces more apatite substances and has good biological activity. The NG coatings can stimulate the natural bone regeneration and repair process by releasing drugs during the process, which can effectively promote bone regeneration and repair after implantation in the body.

The micro-arc oxidation coating was prepared on the surface of the amorphous zirconium sheet, and the influence of frequency on the micro-arc oxidation coating of the Zr-based amorphous alloy was studied. The results show that the change of the frequency of the electrical parameters of the micro-arc oxidation in the silicate micro-arc oxidation bath will promote the transformation of the t-ZrO2 phase to the m-ZrO2 phase in the coating; the frequency affects the gap, uniformity and thickness of the coating. When the frequency is 400 Hz, the coating surface has small voids and no cracks, and the thickness reaches a maximum of 15 μm. With the increase of frequency, the weight loss of the amorphous zirconium micro-arc oxidation coating first decreases and then increases. The wear resistance can be improved.

Physalis alkengi L. var. franchetii (PA) is a type of edible and medicinal plant in Solanaceae. Its chemical components mainly include steroids, flavonoids, alkaloids, amino acids, and phenolic acids. Comprehensive component identification is essential for elucidation of its pharmacological mechanism and quality control. However, its complex chemical composition has caused certain difficulties in the analysis of this traditional Chinese medicine (TCM). Therefore, there is an urgent need to establish a method for rapid classification and identification of chemical components in PA. In this study, the samples were analyzed by ultrahigh-performance liquid chromatography with quadrupole orbitrap mass spectrometry (UHPLC-Q-Orbitrap-MS). The UHPLC system used a C18 column to separate the total extract of PA. The mobile phase consisted of 0.1% formic acid in water and acetonitrile, and the PA extract was analyzed by gradient elution at a flow rate of 0.3 mL/min. In both the positive and negative ion modes, the fragment information was obtained and compared with those of the characteristic fragmentations and neutral losses described in the literature. Mass Frontier™ simulates its fragmentation to quickly identify the target compounds. The mzVault, mzCloud, and ChemSpider databases were utilized to fully analyze the chemical composition in PA. Finally, we successfully screened out 112 chemical components, including 49 steroids, 9 alkaloids, 4 carboxylic acids and derivatives, 8 amino acids, 7 flavonoids, 4 phenols and phenolic acids, 16 phenylpropanoids, 6 terpenoids, 2 piperazines, 1 antibiotic, and 5 others. This study comprehensively analyzed the chemical composition of PA and provides scientific basis and data support for further pharmacodynamic substance studies of PA.

The rigorous design of preclinical experimental studies of candidate neuroprotectants for the treatment of acute ischemic stroke is crucial for the success of subsequent randomized clinical trials. The efficacy of Ginkgo biloba extracts (GBEs) in complex mixtures for the treatment of acute ischemic stroke remains unclear. In this preclinical randomized controlled trail (pRCT), the effects of a novel (n)GBE containing pinitol versus traditional (t)GBE without pinitol were evaluated on the mouse models of acute transient and permanent stroke, separately. The sample size, an important aspect of study design, was calculated based on our experimental data. Mice with ischemia that were induced by transient middle cerebral artery occlusion (tMCAO) or permanent distal middle cerebral artery occlusion (pdMCAO), were treated with vehicle, nGBE, tGBE, or pinitol alone by tail-vein injection. Our results showed that nGBE significantly reduced infarct size in mice with tMCAO compared with vehicle-treated control mice. Both nGBE and tGBE significantly reduced infarct size in mice with pdMCAO compared with the vehicle-treated controls. None of the three treatments rescued weight loss or prevented the neurological deficits in either the tMCAO- or pdMCAO-model mice. These findings suggest that nGBE, which includes all of the components of tGBE and pinitol, is neuroprotective in two ischemic stroke models. Additional studies of complex GBE mixtures for stroke treatment compared to single component medications are undergoing evaluation.

Bone tissue repair materials can cause problems such as inflammation around the implant, slow bone regeneration, and poor repair quality. In order to solve these problems, a coating was prepared by ultrasonic micro-arc oxidation and self-assembly technology on a pure magnesium substrate. We studied the effect of berberine on the performance of the ultrasonic micro-arc oxidation/polylactic acid and glycolic acid copolymer/berberine (UMAO/PLGA/BR) coating. The chemical and morphological character of the coating was analyzed using scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The corrosion properties were studied by potentiodynamic polarization and electrochemical impedance spectroscopy in a simulated body fluid. The cumulative release of drugs was tested by high-performance liquid chromatography. The results indicate that different amounts of BR can seal the corrosion channel to different extents. These coatings have a self-corrosion current density (Icorr) at least one order of magnitude lower than the UMAO coatings. When the BR content is 3.0 g/L, the self-corrosion current density of the UMAO/PLGA/BR coatings is the lowest (3.14 &times, 10&minus, 8 A/cm2) and the corrosion resistance is improved. UMAO/PLGA/BR coatings have excellent biological activity, which can effectively solve the clinical problem of rapid degradation of pure magnesium and easy infection.