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BACKGROUND: Studies have found that single nucleotide polymorphism genotypes in the HTRA1 gene promoter region are associated with intervertebral disc degeneration, while HAPLN1 is associated with osteoarthritis caused by intervertebral disc degeneration. OBJECTIVE: To explore the role of human secretory serine protease HTRA1 and the key group of extracellular matrix HAPLN1 in the pathogenesis of intervertebral disc degeneration. METHODS: This study included 498 postmenopausal female subjects who underwent a physical examination at Dingzhou People’s Hospital from April 2015 to December 2018. TaqMan PCR was used to detect HTRA1 gene promoter rs11200638 single nucleotide polymorphism and HAPLN1 gene 5' flanking rs975563, intron 1 rs10942332, intron 2 rs179851 and intron 4 rs4703570 single nucleotide polymorphism in 498 postmenopausal Chinese women. The correlation between the HTRA1orHAPLN1 gene polymorphisms and the radiographic features of spinal disc degeneration was analyzed. The trial has been approved by the Ethics Committee of Dingzhou People’s Hospital. RESULTS AND CONCLUSION: Among the 498 subjects with the HTRA1 gene rs11200638 single nucleotide polymorphism, 178 were GG homozygotes, 222 were GA heterozygotes, and 98 were AA homozygotes. We compared the parameters of intervertebral disc degeneration in subjects with at least one G allele (GG+GA, n=400) and without G allele (AA, n=98). In HTRA1 gene rs11200638 single nucleotide polymorphism, the score on intervertebral space stenosis in the subjects with GG+GA allele genome was lower than that in the subjects with AA allele (P < 0.001). With the increase of the score on intervertebral space stenosis, the proportion of the subjects with AA alleles increased (P ≤ 0.001). Among the 498 subjects with single nucleotide polymorphisms of the HAPLN1 gene, 137 were homozygous for TT, 230 were heterozygous for CT, and 131 were homozygous for CC. Intervertebral disc degeneration parameters of CC+TT allele (n=361) and TT allele (n=137) were compared. In the HAPLN1 gene, there was a significant difference between the CC+TT and TT alleles of the rs179851 single nucleotide polymorphism in osteophyte formation and intervertebral space stenosis (P < 0.01). Among the HAPLN1 gene rs179851 single nucleotide polymorphisms, the proportion of subjects with TT alleles and intervertebral space stenosis ≥ 6 points increased (P < 0.05). With an increase in osteophyte formation score, the proportion of subjects with TT allele increased (P < 0.001). These results reveal that HTRA1 and HAPLN1 genetic variations at specific genetic loci are associated with intervertebral disc degeneration. [ABSTRACT FROM AUTHOR]

BACKGROUND: Protrusion of intervertebral disc is a complex spinal disease, which is closely related to the degeneration of intervertebral disc. Candidate genes of aggregation proteoglycan metabolic pathway may be related to the severity of protrusion of lumbar intervertebral disc.OBJECTIVE: To assess the association between single nucleotide variants and proteoglycan metabolic pathways in the severity of lumbar disc herniation in patients with chronic mechanical low back pain.METHODS: Sixty patients were classified and described. T2-weighted median sagittal lumbar MRI scans were used to assess the severity of disc herniation and degeneration. Single nucleotide variants genotyping of 20 exons of two candidate genes(proteoglycan, matrix metalloproteinase 3) of lectin metabolic pathway was performed. Age, sex, body mass index and the degree of intervertebral disc degeneration were analyzed by multiple linear regression. The trial was approved by the Ethics Committee of People’s Hospital of Dingzhou on March 1, 2015(approval No. 2015002).RESULTS AND CONCLUSION: The mutants and haplotypes of rs2272023, rs938609, rs2882676, rs698621, rs3825994, rs1042630 and rs3817428 of proteoglycan are related to the severity of lumbar disc herniation. The single nucleotide variants and its haplotype of proteoglycan are related to the severity of lumbar disc herniation. To determine the role of these important single nucleotide variants in the pathogenesis of intervertebral disc herniation, functional genetic studies are necessary. [ABSTRACT FROM AUTHOR]

BACKGROUND: Research on patented technology contributes to understanding the development and key technology of the related field, and enhances the ability to grasp the technological developments in this field. OBJECTIVE: To investigate the patent application situation and technical development route in the field of fully-degradable polylactic acid stents. METHODS: We searched the patent applications for fully-degradable polylactic acid stents all over the world, and analyzed relevant information in the following aspects: annual application quantity, the distribution of the main applicants, the branches of the patent technology, the analysis of the important applicants. Afterwards, we focused on the blending modification of polylactic acid stents, and analyzed its core patents and the development of patented technology. RESULTS AND CONCLUSION: The fully-degradable polylactic acid stent is the focus direction of current research in the field of vascular stents. Materials, technique and structural design are the main aspects for patent applications in this field. Among them, the application for improvement of materials is the most frequently conducted, which is the earliest branch of technology in this field. In terms of technical requirements, improving the mechanical properties of scaffolds, controlling the degradation rate of stents, and improving the controlled release of drugs are the main concerns. [ABSTRACT FROM AUTHOR]

BACKGROUND: Synthetic calcium phosphate ceramic materials are similar to the inorganic components of natural bone tissue. Functional design through surface morphology and chemical composition can endow them with excellent osteoconductive and osteoinductive properties. The development of calcium phosphate ceramic materials with osteoinductive properties is the current research hotspot. OBJECTIVE: To endow the submicron topology tricalcium phosphate ceramics with osteoinductive properties through material morphology regulation and functional design, and test their physicochemical properties and osteoinductive properties. METHODS: Novel tricalcium phosphate ceramics were prepared by high temperature sintering method. Clinical available Bio-oss bone meal was set as the control group. The sample surface morphology, the protein adsorption capacity, and the in vitro mineralizability of the two materials were characterized. Human periodontal membrane stem cells at passage 3 were co-cultured with the extracts of the two materials. Cell proliferation was detected by CCK-8 assay. Alizarin red staining was used to detect cell mineralization performance. The human periodontal ligament stem cells at passage 3 were seeded on the surfaces of the two materials. Early osteogenesis was detected by alkaline phosphatase staining. The expression of osteogenesis-related factors was detected by qRT-PCR. RESULTS AND CONCLUSION: (1) Scanning electron microscope exhibited that both materials had microporous surfaces with granular texture. Bio-Oss particles were significantly smaller than that of tricalcium phosphate ceramics. The total porosity, macroporosity, and microporosity were similar for both materials. Tricalcium phosphate ceramics were mainly submicron pores, with a grain size of 100 nm-1.0 μm. Bio-Oss bone meal was mainly nano-scale pores. In vitro mineralization experiments displayed that the ability of the surface of tricalcium phosphate ceramics to induce bone apatite deposition was stronger than that of Bio-Oss bone meal. Compared with Bio-Oss bone meal, tricalcium phosphate ceramics could adsorb more proteins from fetal bovine serum and bovine serum albumin solution (P < 0.05). (2) CCK-8 assay demonstrated that both materials promoted cell proliferation, and there was no significant difference between the two groups (P > 0.05). (3) The alkaline phosphatase activity in the tricalcium phosphate ceramic group was higher than that in the Bio-Oss group at 4 and 7 days of culture (P < 0.05), and the number of mineralized nodules at 21 days of culture was more than that in the Bio-Oss group; the mRNA expression levels of alkaline phosphatase, osteocalcin, osteopontin and Runx-2 were higher than those in the Bio-Oss group on 7 and 14 days of culture (P < 0.05). (4) The results showed that the new calcium phosphate ceramics have superior in vitro osteoinductive properties. [ABSTRACT FROM AUTHOR]

BACKGROUND: Previous studies have found that panax notoginseng saponins have a certain protective effect on immunological liver injury in mice. OBJECTIVE: To explore the therapeutic effect of notoginsenoside R1 on carbon tetrachloride-induced liver fibrosis in rats. METHODS: Experimental liver fibrosis model was made by carbon tetrachloride in male Sprague-Dawley rats. Then 30 g/L notoginsenoside R1 (60 mg/kg) was given once daily for 4 and 6 weeks in the treatment group. Rats in the control and model group were given distilled water of the same volume. Histopathological observation with hematoxylin-eosin staining and Masson’s trichrome staining was used to evaluate the changes of liver structure and fibrosis degree. The expression of collage type I, α-smooth muscle actin and transforming growth factor-β1 mRNA of hepatic tissue was measured by qRT-PCR method. The experimental protocol was approved by the Animal Experiment Ethics Committee of Kunming Medical University (approval No. KMMU2018018). RESULTS AND CONCLUSION: Liver histopathology showed that notoginsenoside R1 improved the degree of liver fibrosis. The expression levels of collagen type I, α-smooth muscle actin and transforming growth factor-β1 mRNA were reduced significantly in the treatment group compared with the model group (P < 0.05). But there was no significant difference after 4 and 6 weeks of treatment with notoginsenoside R1. Overall findings indicate that notoginsenoside R1 can slow down the progression of carbon tetrachloride-induced liver fibrosis in rats to a certain extent. [ABSTRACT FROM AUTHOR]

BACKGROUND: The use of bladder acellular matrix as a free graft to repair urethral defects and induce urinary tract regeneration has achieved certain results, but this method cannot fundamentally solve insufficient angiogenesis of the graft. OBJECTIVE: To observe the effect of bladder acellular matrix (BAM) combined with vascular endothelial growth factor (VEGF) in the repair of rabbit urethral defects. METHODS: Thirty adult New Zealand rabbits were randomly allocated into five groups (n=6 per group), including healthy control group, sham operation group, model group, BAM group, and BAM combined with VEGF group (VEGF-BAM group). Animal models of urethral defect were made in the latter three groups. The animals were sacrificed at 4 and 12 weeks after surgery, respectively. The penis was immediately harvested for standardized passive flowmetry, urethral radiography and subsequently fixed for immunohistochemical staining for evaluation. RESULTS AND CONCLUSION: (1) The average urinary flow rate of the VEGF+BAM group was significantly higher than that of the model group and BAM group at 4 and 12 weeks after surgery (P < 0.05), while there was no difference from the healthy control group and sham operation group. (2) Urethral radiography at 12 weeks after surgery indicated that urethra continuity was repaired with no urethral fistula in the VEGF+BAM group, but not incompletely in the model and BAM groups. (3) Hematoxylin-eosin staining results indicated there were more collagen fibers and infiltrated lymphocytes in the model group, with the fiber arrangement being disordered; the collagen matrix in the VEGF+BAM group was basically degraded, new collagen fibers arranged regularly, and there were many blood vessels, but no hemangioma; and in the BAM group, massive collagen deposition and less blood vessels were observed. (4) Masson staining results indicated that less collagen deposition was observed in VEGF+BAM group compared with BAM group and model group at 12 weeks after surgery (P < 0.05), which was similar to the healthy control group and sham operation group (P > 0.05). (5) CD31 staining results indicated that the local density of new blood vessels in the VEGF+BAM group was significantly higher than that in the BAM and models groups at 12 weeks after surgery (P > 0.05), which was also close to the value in the healthy control and sham operation groups (P > 0.05). (6) Regeneration of urethral smooth muscle in the VEGF+BAM group was significantly better than that in the BAM and model groups at 12 weeks after surgery (P < 0.05), as indicated by a-SMA immunohistochemical staining. Moreover, there was no significant difference among VEGF+BAM group, sham operation group and health control group. To conclude, BAM scaffolds combined with VEGF show a totally potential capacity in inducing the urethral reconstruction. The combined use of VEGF and BAM can stimulate angiogenesis, decrease the rate of collagen deposition, promote urethral smooth muscle regeneration, and improve the urethra regeneration microenvironment in urethral reconstruction. [ABSTRACT FROM AUTHOR]

BACKGROUND: Neuron culture and cell transfection technologies are important means to study the development and pathophysiologic mechanism of neurons in vitro, but the purity and transfection efficiency of primary cultured cortical neurons are poor. OBJECTIVE: To establish a simple, efficient and stable method of culture and transfection method of primary neurons in vitro. METHODS: Primary cortical neurons were harvested from neonatal 1-day rat brains under aseptic condition, which was digested with 0.25% trypsin prior to centrifugation and made into cell suspensions, followed by being seeded into Neurobasal-A medium (5×109 L-1 per pore). The morphological characteristics of neurons were observed by inverted microscope; two neuron-specific markers (MAP2 and Tuj1) were used for immunolabeling to identify the cultured cells; the transfection efficiency of neurons was tested by Lipofectamine 2000 and Block-iT Transfection Kit. RESULTS AND CONCLUSION: The neurons cultured in vitro exhibited interconnected networks after culture for 7 days. All the cultured neurons displayed MAP2 and Tuj1 immunoreactivity. The highly effective transfection was observed under fluorescence microscope using Lipofectamine 2000 transfected neurons. In summary, the culture method of primary cerebral cortex neurons can be adopted to obtain highly purified neurons. Besides, high transfection efficiency of primary neurons can be realized by artificial liposome. [ABSTRACT FROM AUTHOR]