The biomimetic method, which mimics the natural dep osition of biologic apatite, has opened up a new way to develop biomaterials. Th is paper gives a brief introduction of various biomimetic methods to deposit apatite coatings, and the mechanical and biological properties of the coatings.

OBJECTIVE: To establish a new method for determination of strychnine alkaloid in biological fluids based on molecularly imprinted polymers. METHODS: A strychnine molecularly imprinted monolithic column was prepared by in-situ molecularly imprinted technique. The polymer was filled to a 1cm column, and a method was developed to concentrate and determine strychnine alkaloids in biological fluids. RESULTS: the limit of detection of the method was 4.9 ng, and the recoveries were more than 92%. The relative standard deviations were smaller than 6.59%. The linear correlation coefficients of standard curves were 0.999 1 and 0.9966 respectively. This method was applied to concentrate and determine strychnine in plasma and urine of poisoned rabbit. CONCLUSION The new method could concentrate and simultaneously determine strychnine alkaloids in biological fluids, and it was applied to forensic toxicological analysis.
Alkaloids/analysis* ; Animals ; Chromatography, High Pressure Liquid/methods* ; Humans ; Male ; Polymers/chemistry* ; Rabbits ; Sensitivity and Specificity ; Strychnine/urine*

Some techniques of compounding bioactive ceramics and polymer biomaterials with mechanical and biological properties and the clinical applications of the composites produced are presented.
Biocompatible Materials ; chemistry ; Biomechanical Phenomena ; Ceramics ; chemistry ; Humans ; Polymers ; chemistry ; Surface Properties

Ion beam enhanced deposition (IBED) has been applied to prepare titanium oxide layer on titanium alloy (Ti6A14V) in order to improve its biocompatibility. The layer on titanium alloy is even, and the elements Al and V in substrate are not detected. The layer is composed of TiO containing nitrogen oriented along (111) plane. The critical load of the layer in scratch test is 16.8 N. Morphological observation reveals the layer ends in a failure caused by plastic deformation.
Biocompatible Materials ; chemistry ; Coated Materials, Biocompatible ; chemistry ; Ions ; chemistry ; Surface Properties ; radiation effects ; Titanium ; chemistry ; X-Ray Diffraction

Objective: To look for a potent gene that may cause intervertebral disc degeneration in a family with intervertebral disc herniation by exome sequencing four patients with intervertebral disc herniation so as to provide possible help for studies on the causes and mechanisms of intervertebral disc diseases. Methods: We collected the serum of patients with lumbar disc herniation treated at The First Affiliated Hospital of Xi'an Jiaotong University, The First Affiliated Hospital of Xi'an Medical College, and Xi'an Tangcheng Hospital from January 2010 to December 2016. A detailed medical history was collected and family survey was conducted to find a family with high incidence of degenerative intervertebral disc disease. Then we found 4 patients aged 20 to 50 years with lumbar disc herniation in this family. Exome sequencing was used to analyze the common exon mutation sites of the 4 patients to find the common mutation sites. Results: The common mutation IGFBP6, Chr12:g.53494591T>C, was detected in the 4 samples. The Sanger sequencing performed in-family validation revealed that the IGFBP6 showed a C/T type in all the four patients and a T type in all the five normal controls. Finally, verification was performed in 200 normal controls and no mutation was found in this site. Therefore, the IGFBP6 might be the effector gene that caused intervertebral disc degeneration in this family. Conclusion: The mutation site of IGFBP6, c.T430C (p.S144P) (Chr12:g.53494591T>C), may be a factor that contributes to the high incidence of intervertebral disc herniation in this family. We still need to verify the function of the gene in future. Our study has also confirmed that exome sequencing technology can be applied to the detection of disease-causing genes in complex diseases.

Hydroxyapatite and fluoride-substituted hydroxyapatite powders are synthesized by wet method, compacted into pallets and subjected to heat treatment at 300, 600, 900℃ respectively. Analysis of the fluoride-substituted hydroxyapatites and HA by FTIR spectroscopy indicated that with the increasing of sintering temperatures, the phase-pure fluoride-substituted hydroxyapatite and stoichiometric hydroxyapatite could be got. According to the X-ray diffraction analysis, the fluoride-substituted hydroxyapatite is less stable for decomposing into β-Ca3(PO4)2 at the temperature of 900℃. The in vitro bioactivity of the fluoride-substituted hydroxyapatites and hydroxyapatite heat treated at 900℃ was assessed by immersion testing in simulated body fluid (SBF). Both scanning electron microscopy (SEM) analysis and ionic solution changes (Ca2+) demonstrated that the low fluoride content apatite could induce a surface bonelike apatite layer formation.

With the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) all over the world, there is an increasing number of children with such infection. Angiotensin-converting enzyme 2 (ACE2), one of the binding sites for SARS-CoV-2 infection in humans, can bind to viral spike proteins, allowing transmembrane serine protease (TMPRSS2) to activate S-protein to trigger infection and induce the production of various inflammatory factors such as interleukin-1, interferon-l, and tumor necrosis factor. Compared with adults, children tend to have lower expression levels of ACE2 and TMPRSS2, which are presumed to be associated with milder symptoms and fewer cases in children. The article summarizes the research advances in the role of ACE2 during SARS-CoV-2 infection, in order to help understand the pathogenic mechanism of SARS-CoV-2 and provide a reference for better development of drugs and vaccines to prevent and treat coronavirus disease 2019 in children.
Angiotensin-Converting Enzyme 2/metabolism* ; COVID-19 ; Child ; Humans ; Receptors, Virus/metabolism* ; SARS-CoV-2 ; Serine Endopeptidases/metabolism*

BACKGROUND: Lung cancer has the highest mortality in China. Different treatments are of great significance to the prognosis of patients. By comparing stage Ia non-small cell lung cancer (NSCLC) patients' survival rates for ablation and for sub-lobectomy, we studied the difference in the effects of the two treatments on patient prognosis. METHODS: Using the Surveillance, Epidemiology, and End Results (SEER) database, we screened eligible patients with stage Ia NSCLC from January 2004 to December 2015. Then, 228 patients treated with ablation and 228 patients treated with sub-lobotomy were then selected based on propensity score matching. After stratification, matching, and adjustment the Kaplan-Meier analysis was performed to compare the overall survival rates of patients treated with the two procedures. RESULTS: The Kaplan-Meier survival analysis showed that there is a significant difference between the ablation group and the sub-lobectomy group (P<0.05). In the univarlable analysis, the hazard ratio (HR) of sub-lobotomy group was 0.571 (95%CI: 0.455-0.717) compared with the ablation group. Patients treated with sub-lobectomy had a 0.571 times greater risk of adverse outcomes than those treated with ablation. In the multivariable analysis, the HR for sub-lobectomy group was 0.605 (95%CI: 0.477-0.766) compared with the ablation group. Patients treated with sub-lobectomy had a 0.605 time greater risk of adverse outcomes than those treated with ablation. The results suggested that the overall survival rate of patients with stage Ia NSCLC treated with sub-lobotomy was higher than that of patients treated with ablation. CONCLUSIONS This study suggests that there is a significant difference in overall survival of stage Ia NSCLC patients treated with ablation and with sub-lobotomy. Patients treated with sub-lobotomy for stage Ia NSCLC had higher overall survival than those treated with ablation.

Microspheres (MS) are an excellent transarterial chemoembolization carrier for cancer treatment. Then the Bletilla striata polysaccharide (BSP) that was isolated from the rattan of Bletilla striata was used as skeleton material, and the matrine (ME) loaded Bletilla striata polysaccharide microspheres (ME-BSPMS) were prepared by emulsify-chemical crosslinking method. ME-BSPMS was characterized for appearance shape, particle size, drug loading, swelling ratio, suspension property, drug entrapment condition and in vitro release characteristics. The results showed that the ME-BSPMS appeared as round spherical and smooth shape by SEM, with an average size of (85 ±7) μm. ME-BSPMS with a good suspension in physiological saline and the swelling ratio could reach upwards of (53 ±4.2)% in 20 minutes, also with a large amount of drug loading of (30.12 ±3.25)%. The results of DSC scanning indicate that good compatibility exists between the ME and BSP, and the ME could be embedded fully in the matrix of the ME-BSPMS. The accumulation drug release from ME-BSPMS was (25.38 ±1.57)% at 12 h, this suggests that the ME-BSPMS has a good sustained release effect. These results indicate that the ME-BSPMS may be a promising transarterial chemoembolization carrier for cancer treatment.

Flexible liposomes are an excellent drug delivery nanocarrier, however, the leakage of drugs from liposomes has become common technical obstacle in the industry and also hindered its further application seriously. It is very urgent and necessary to avoid or reduce the leakage of drugs from liposomes. In this work, five kinds of essential oils such as Folium Artemisiae Argyi oil (FA), Folium Eucalypti oil (FE), Arabian Jasmine oil (AJ), Syzygium Aromaticum oil (SA) and Fructus Forsythiae oil (FF) were encapsulated in the lipid bilayer of palmatine chloride (PC) loaded flexible nano-liposomes (PFL), then the optimal essential oil and its dosage level were determined by the external leakage curve of PC. The female Japanese white rabbits were used to evaluate the vaginal irritancy potential of liposomes samples. The pharmaceutical properties such as encapsulation efficiency, particle size, zeta potential, deformability and structure of liposomes samples were evaluated. In order to investigate the permeability of liposomes samples to deliver PC across skin and mucous membrane in vitro, the side-by-side diffusion cells were used. The results showed that the leakage of hydrosoluble PC from PFL was reduced at different degrees by the essential oils in the lipid bilayer of PFL, however, the reduction in leakage degree was obviously higher for FA than thoses of FE, AJ, SA and FF (P < 0.05), and the highest reduction in leakage degree was obtained when the FA and lipid mass ratio was 1:6. The encapsulation efficiency, particle size, zeta potential and deformability of PFL were not significantly changed after FA was encapsulated in the lipid bilayer of the PFL (P > 0.05), so did the lamellar structure of PFL. In addition, the transdermal and transmucosal permeability of PC were also enhanced obviously by encapsulating FA in the lipid bilayer of PFL, and there was no vaginal/vulvar irritation observed in the rabbits. In summary, the drug leakage was reduced by encapsulating suitable essential oil (such as FA) in the lipid bilayer of flexible liposomes, and the vaginal mucosa permeability were improved for the drug. These results provide a novel technique in the improvement of flexible nano-liposomes for drug delivery.