Search

Purpose: This study aimed to investigate the association between unilateral high-riding vertebral artery (HRVA) and morphological changes in the atlantoaxial joint (AAJ) and to determine whether unilateral HRVA is a risk factor for atlantoaxial osteoarthritis (AAOA). Methods: We conducted a retrospective analysis of 2496 patients admitted to our medical center between January 2020 and December 2022 who underwent CT imaging of the cervical spine. Two hundred and seventy-two patients with unilateral HRVA (HRVA group) were identified and a respective 2:1 age- and sex-matched control group without HRVA was built. Morphological parameters, including C2 lateral mass settlement (C2 LMS), C1/2 coronal inclination (C1/2 CI), lateral atlanto-dental interval (LADI), and C1/2 relative rotation angle (C1/2 RRA) were measured. The degree of AAOA was recorded. Risk factors associated with AAOA were identified using univariate and multivariable logistic regression analyses. Results: The study included 61.4% women, and the overall average age of the study population was 48.7 years. The morphological parameters (C2 LMS, C1/2 CI, and LADI) in AAJ were asymmetric between the HRVA and the non-HRVA sides in the HRVA group (p < 0.001). These differences in parameters (d-C2 LMS, d-C1/2 CI, and d-LADI) between the HRVA and the non-HRVA sides, and C1/2 RRA were significantly larger than those in the control group. Eighty-three of 816 patients (10.2%) with AAOA had larger values of d-C2 LMS, d-C1/2 CI, d-LADI, and C1/2 RRA compared with the patients without AAOA (p < 0.05). The multivariable logistic regression analysis indicated that unilateral HRVA [adjusted odds ratio (OR) = 2.6, 95% CI: 1.1–6.3, p = 0.029], age in the sixth decade or older (adjusted OR = 30.2, 95% CI: 16.1–56.9, p < 0.001), women (adjusted OR = 2.1, 95% CI: 1.0–5.6, P = 0.034) were independent risk factors for AAOA. Conclusion: Unilateral HRVA was associated with asymmetric morphological changes of nonuniform settlement of C2 lateral mass, lateral slip of atlas, and atlantoaxial rotation displacement. Besides age ≥ 60 years and females, unilateral HRVA is an independent risk factor for AAOA. [ABSTRACT FROM AUTHOR]

Electrohydrodynamic (EHD) conduction pumping can be applied in many macroscopic devices accompanied by a high electric field intensity (106 V/m). Microscale flow generation has become increasingly important with the widespread development of thermal management devices, which are currently used to cool high heat flux sources with small surface areas and are found in a variety of electronic, controlled heat transfer, and aerospace scenarios. Additionally, the magnitude of the applied voltage can be significantly reduced in micropumping, resulting in power savings and a reliable method for flow generation. In this study, we examine the dynamic characteristics of a conduction micropump embedded within a rectangular microchannel, showing the effects of Coulombic driving forces, different channel heights, polymer elasticity, and viscosity ratios. The results show that electric power consumption can vary by two orders of magnitude for increasing channel height. As the polymer concentration increases, the maximum velocity decreases significantly and can reach 50% of that of the unadded polymer with a plunger-like distribution. The flow rate depends linearly on the polymer concentration, but exhibits non-monotonic curve with the polymer elasticity. It means that the flow rate performance of the micro-pump can be kept controllable by tuning the viscosity ratio, providing some suggestions for some regulated flow applications. [ABSTRACT FROM AUTHOR]

Dinaciclib is a selective cyclin-dependent kinase inhibitor, but its radiosensitizing effect remains unclear. The aim of this study is to investigate the radiosensitizing effect of Dinaciclib on cervical cancer cells. Two cervical cancer cell lines, Hela and Siha, were selected, and the IC50 was determined by CCK8. The radiosensitizing effect of Dinaciclib was verified by plate cloning assay, and the G2/M phase arrest and apoptosis of IR cells were verified by flow cytometry. Immunofluorescence assay was used to verify the formation of γH2AX foci following DNA damage. Western blot was performed to detect cell cycle, apoptosis, autophagy, and DNA damage-related pathways. Dinaciclib increased the cell sensitivity to IR. IR induced G2/M phase arrest and apoptosis, and Dinaciclib enhanced this effect. Further, Dinaciclib delayed DNA repair, including non-homologous end joining repair and homologous recombination repair, and reduced the expression of DNA repair proteins Ku80 (SiHa cells), Ku70, and RAD51, as well as the expression of apoptotic marker Bcl-2. The expression of autophagy marker Beclin1 induced tumor cell death and increased the formation of DNA damage marker γH2AX foci. Dinaciclib improves the sensitivity of cervical cancer cells to IR by inducing cell cycle arrest, delaying DNA repair, and increasing apoptosis. However, further research is needed to unravel the complexity of DNA repair pathways. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the long-term clinical outcomes of degenerative lumbar scoliosis (DLS) with the administration of multisegment transforaminal lumbar interbody fusion (TLIF) combined with Ponte osteotomy long-level fixation fusion, as well as to identify the factors affecting health-related quality of life (HRQOL). Methods: This was a retrospective single-centre study involving comprehensive clinical data. The Oswestry Disability Index (ODI), visual analog scale (VAS) outcomes, and Scoliosis Research Society (SRS-22) questionnaire were recorded to assess HRQOL. A correlation analysis was performed to determine the association between HRQOL and radiographic parameters. Results: A total of 41 consecutive patients (15 males and 26 females) met the inclusion criteria with a follow-up of 8.62 ± 1.20 years. Factors associated with HRQOL were significantly improved post-operation. Global sagittal parameters, including the sagittal vertebral axis (SVA) and T1 pelvic angle (TPA), and local parameters, including apical vertebral translation (AVT) and apical vertebral rotation (AVR), were significantly improved at the last follow-up. Significantly strong correlations between each clinical and radiographic parameter were demonstrated. Moreover, a multiple linear regression analysis demonstrated that the differences in AVT and AVR were significantly correlated with the difference in lumbar lordosis (LL), which was significantly correlated with the differences in SVA and TPA. Conclusion: The surgical treatment of DLS with multisegment TLIF accompanied by Ponte osteotomy and long-level fixations improved the quality of life of patients with a long-term effect. AVR correction is an important factor for LL restoration that significantly correlates with improvements in the sagittal balance parameters SVA and TPA, which are key factors for guaranteeing good HRQOL. [ABSTRACT FROM AUTHOR]

A Gram-stain-negative, rod-shaped, facultatively anaerobic, motile and spore-forming strain designated FJAT-44921T was isolated from red mud collected from Chiping County, Shandong Province, China. The 16S rRNA gene sequence result showed that strain FJAT-44921T shared a low sequence identity (96.6%) with the members of the genus Bacillus. Growth was observed at pH 8.0–10.0 (optimum pH 9.0), 10–40 °C (optimum 20–25 °C) with 0–8% (v/w %) NaCl (optimum 4–6 v/w %). FJAT-44921T consists of MK-7 as the isoprenoid quinone and meso-2,6-diaminopimelic acid as the cell-wall diamino acid. The predominant fatty acids were anteiso-C15:0, iso-C15:0, C16:0, and anteiso-C17:0. The polar lipids were diphosphatidylglycerol, phosphatidyl glycerol, phosphatidylmethylethanolamine, unidentified phospholipid, and unidentified aminophospholipid. The genomic DNA G + C content was 37.3 mol%. The average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values between FJAT-44921T and other closely related Bacillus members were lower than the recognized threshold values of ANI (95–96%) and dDDH (70%) recommended as the criterion for interspecies identity. The type strain is FJAT-44921T (=CCTCC AB 2016196T =DSM 104630T). [ABSTRACT FROM AUTHOR]

Most lung cancer bone metastasis are characterized by osteolytic destruction and osteoblastic activity is significantly decreased, suggesting that hypoxia may play a critical role in the process, but the underlying mechanisms remain unknown. Semaphorin 4D (Sema4D) is a recently discovered osteogenic inhibitory factor that is expressed at high levels in lung cancers. Here, CoCl2-induced hypoxia significantly enhanced the inhibitory effect of lung cancer cell conditioned media on osteoblast differentiation by inducing the expression and secretion of Sema4D in a HIF-1α- but not HIF-2α-dependent manner. Moreover, HIF-1α directly regulated Sema4D expression by binding to bases 1171 to 798 in the Sema4D promoter. Furthermore, hypoxia increased Sema4D secretion by upregulating a disintegrin and metalloproteinase 17 (ADAM17) expression in lung cancer in a HIF-1α-dependent manner. In bone metastasis samples from 49 patients with lung cancer, Sema4D and ADAM17 expression significantly correlated with HIF-1α expression and strongly correlated with a poor differentiation status and osteolytic bone destruction. These results provide the first evidence that HIF-1α-induced Sema4D expression and secretion play important roles in lung cancer osteolytic bone metastasis by inhibiting osteoblast differentiation, thereby providing potential strategies for the treatment of bone metastasis via targeting osteoblasts. [ABSTRACT FROM AUTHOR]

In this paper, a two-stage oligopoly game of semi-collusion in production is analyzed and expounded, where at first stage all firms compete in R&D and at second stage all firms coordinate the production activities in order to make their joint profit maximized. Not only the local stability of equilibriums, but also the existence, stability and direction of flip bifurcation of the discrete nonlinear model are investigated by using the normal form method and the center manifold theory. Then, the validity of the theoretical analysis is justified through numerical simulation. We find that the model we built can exhibit very complex dynamical behaviors, but it cannot undergo the Neimark-Sacker bifurcation. Also the coexistence of attractors is found through numerical simulation, and their basins of attraction are simulated. At last of this paper, the chaotic motion of the proposed model is controlled by delayed feedback control method. [ABSTRACT FROM AUTHOR]

Introduction: Several types of stem cells have been successfully demonstrated to exist in the human degenerated intervertebral disc (IVD), which is composed of annulus fibrosus (AF), nucleus pulposus (NP) and cartilage endplate (CEP). However, the differences in the biological characteristics among these and bone marrow derived mesenchymal stem cells (BM-MSCs) remain unclear.Materials and Methods: To investigate this issue, cells were harvested from human AF, NP, CEP, and bone marrow, respectively; passage 2 cells were selected using the agarose suspension culture system to obtain stem cell clones. Following expansion in vitro, stem cells from different anatomical regions were compared regarding the morphology, proliferation ability, immunophenotypic expression, and multi-lineage differentiation capacity. In addition, stem cell-alginate bead compositions were constructed for the comparison of DNA and sGAG content.Results: There were subtle differences regarding cell morphology, but no significant differences in proliferation ability among the four types of stem cells. For the immunophenotypic analysis, all stem cells basically fulfilled the criteria for mesenchymal stem cells (MSCs), which have been published by the International Society for Cellular Therapy (ISCT), with a significant difference in CD105 expression. A comparison of the osteogenic capacities indicated: cartilage endplate-derived stem cells (CESCs) > annulus fibrosus-derived stem cells (AFSCs) > BM-MSCs > nucleus pulposus-derived stem cells (NPSCs). The chondrogenesis difference was similar to osteogenesis. For adipogenesis: BM-MSCs >NPSCs >CESCs >AFSCs. In the stem cell/alginate composition, the CESCs consistently showed the superior chondrogenic potential among all those cell types.Conclusions: Our data indicated that all the four types of stem cells shared some similar biological properties (regarding shape, proliferation ability and immunophenotypic expression). CESCs, which had the strongest osteogenic and chondrogenic potentials, may serve as excellent seed cells for NP/cartilage or bone tissue engineering. [ABSTRACT FROM AUTHOR]

The objective of this study was to explore the relationship between single-nucleotide polymorphisms (SNPs) of the protein kinase C gamma (PRKCG) gene and osteosarcoma susceptibility in Chinese Han population. A total of 610 cases of osteosarcoma patients and 610 healthy individuals were enrolled in this study. TaqMan method was used to compare genotypes and the allelic distribution frequency of three SNPs (rs454006, rs2242245, and rs8103851) in the PRKGG gene between osteosarcoma patients and healthy individuals. Osteosarcoma patients were grouped according to different clinical parameters (age, gender, pathological types, tumor location, Enneking staging, tumor metastasis and treatment) to compare genotype and allele frequency among different groups as well as to explore the relationship between gene polymorphisms and different clinical parameters. The rs454006 polymorphisms of the PRKCG gene include the CC, CT, and TT genotypes. The differences in genotype frequency and allele frequency between osteosarcoma patients and healthy individuals were significant (both P < 0.001). There was no significant different between osteosarcoma patients and healthy individuals in rs8103851 and rs2242245 polymorphisms of the PRKCG gene (both P > 0.05). The differences of the rs8103851 genotype frequency and allele frequency in patients with metastatic osteosarcoma and patients without metastasis were significant (both P < 0.001). The distribution frequencies of the CG and GG genotypes as well as the G allele in patients with metastatic osteosarcoma were higher than in patients without metastasis. The genotype frequency and allele frequency of rs454006 and rs2242245 did not correlate with clinical parameters. The rs454006 polymorphism of the PRKCG gene correlated to osteosarcoma susceptibility and might increase the risk of osteosarcoma. The rs8103851 correlated to metastatic osteosarcoma and could be risk factors for metastatic osteosarcoma. [ABSTRACT FROM AUTHOR]

DNA G-quadruplexes are not only attractive drug targets for cancer therapeutics, but also have important applications in supramolecular assembly. Here, we report a platinum(II)-based tripod (Pt-tripod) specifically binds the biological relevant hybrid-1 human telomeric G-quadruplex (Tel26), and strongly inhibits telomerase activity. Further investigations illustrate Pt-tripod induces the formation of monomeric and multimeric Pt-tripod‒Tel26 complex structures in solution. We solve the 1:1 and the unique dimeric 4:2 Pt-tripod-Tel26 complex structures by NMR. The structures indicate preferential binding of Pt-tripod to the 5ʹ-end of Tel26 at a low Pt-tripod/Tel26 ratio of 0-1.0. After adding more Pt-tripod, the Pt-tripod binds the 3ʹ-end of Tel26, unexpectedly inducing a unique dimeric 4:2 structure interlocked by an A:A non-canonical pair at the 3ʹ-end. Our structures provide a structural basis for understanding the dynamic binding of small molecules with G-quadruplex and DNA damage mechanisms, and insights into the recognition and assembly of higher-order G-quadruplexes. DNA G-quadruplexes occur in oncologically relevant regions, thus are interesting targets for cancer research and treatment. Here, the authors solved the 1:1 and 4:2 (ligand/DNA) NMR structures of human telomeric DNA in complex with platinum(II)-tripod ligand and show that the binding is dynamic. [ABSTRACT FROM AUTHOR]