Lipopolysaccharide inhibits osteoblast formation and receptor activator of nuclear factor-κB ligand degradation via autophagy inhibition.

Lipopolysaccharide (LPS) and Receptor Activator of Nuclear Factor-κB Ligand (RANKL) are the two important factors causing bone loss, which is an important pathogenesis for osteoporosis. However, the relationship between LPS and RANKL is not yet clear. LPS can be involved in the weakened osteoblast formation as an autophagy regulator, and osteoblasts and their precursors are the source cells for RANKL production. Our study aimed to explore the relationship between autophagy changes and RANKL production during LPS-regulated osteoblasts. Our results showed that LPS inhibited autophagy (LC3 conversion and autophagosome formation) and enhanced the protein and mRNA expression of RANKL in MC3T3-E1 osteoblast precursor line. Autophagy upregulation with Rapamycin over BECN1 overexpression rescued LPS-inhibited osteoblast formation and -promoted RANKL protein production in MC3T3-E1 cells. In vivo experiments supported that damaged bone mass, bone microstructure, osteoblastic activity (ALP and P1NP production by ELISA assays) and enhanced RANKL production by LPS administration were partially rescued by Rapamycin application. In conclusion, LPS can inhibit autophagy in osteoblast precursors, thereby inhibiting osteoblast formation and RANKL autophagic degradation.

Persulfate enhanced removal of bisphenol A by copper oxide/reduced graphene oxide foam: Influencing factors, mechanism and degradation pathway.

The CuO/reduced graphene oxide foam (CuO/RGF) with excellent recyclability was prepared via hydrothermal method followed by freeze drying treatment for bisphenol A (BPA) removal via activating peroxydisulfate (PDS). SEM, XRD, XPS, FT-IR, BET, and TG techniques were used to investigate the structure and property of CuO/RGF. The effect of degradation conditions (pH, PDS amount, Cl-, HCO3-, HA and FA) on BPA removal by CuO/RGF were investigated. The result presented that CuO nanosheet was inserted into the RGF carrier with three-dimensional structure. The degradation rate constant of BPA over CuO/RGF (0.00917 min-1) was 1.24 and 6.46 times higher than those of BPA over CuO (0.00714 min-1) and RGF (0.00142 min-1). More importantly, the pore structure of RGF can successfully limit the release of Cu (II) compared to pure CuO. According to quenching test as well as electron spin resonance (EPR) spectra, BPA degradation was triggered by 1O2, •OH and SO4•-, which was the combination of nonradical (1O2) and radical activation of PDS (•OH and SO4•-). The possible degradation route of BPA was proposed based on intermediates obtained by combining solid phase extraction pretreatment technique with high performance liquid-mass spectrometry. After assessing the viability of MCF-7 cells, we can see that the estrogenic activities of treated solution reduced without producing stronger endocrine disruptors.

Accuracy and digital screw path design of TiRobot-assisted pedicle screw placement for lumbar spondylolisthesis.

PURPOSE: To investigate lumbar spondylolisthesis screw placement assisted by TiRobot in terms of digital screw path design, accurate implementation, and accuracy evaluation method. METHODS: In this study, we enrolled 40 patients with lumbar spondylolisthesis between December 2020 and August 2021 who underwent spine surgery at the Affiliated Hospital of PuTian University. Pre-operative computed tomography position and screw path designation, intra-operative pedicle screw placement according to pre-operative planning, and post-operative evaluation of the accuracy of screw placement were performed. 3D coordinates of the entry and exit points before and after the operation were collected. The qualified points at different levels of accuracy were counted. The screw placement accuracy was based on the absolute difference using the Chi-squared test. RESULTS: In total, 194 screws were successfully implanted with no screws penetrating the cortex. The absolute difference of entry points X, Y, and Z coordinates before and after the operation was 0.425 ± 0.294 mm, 0.417 ± 0.310 mm, and 0.466 ± 0.327 mm, respectively. The corresponding values in terms of exit points were 0.702 ± 0.470 mm, 0.963 ± 0.595mm, and 0.983 ± 0.566 mm, respectively. No obvious differences in coordinates before and after the operation were observed with an entry point degree of accuracy of ≥ 1.2 mm and exit point degree of accuracy of ≥ 2.1 mm. Therefore, the real surgery was consistent with the design. CONCLUSIONS: TiRobot-assisted lumbar spondylolisthesis surgery achieved optimal path designation and precise surgery.

The COVID-19 Pandemic and Overall Wellbeing: Mediating Role of Virtual Reality Fitness for Physical-Psychological Health and Physical Activity.

Background: Virtual reality applications are made for various objectives such as business, entertainment, education, and healthcare. Anxiety, phobias, distress, disordered eating, drug addiction, panic disorder, post-traumatic stress disorder, schizophrenia, bipolar disorder, psychosis, depression, and autism spectrum disorders may benefit from virtual reality-based approaches. The 2019 coronavirus (COVID-19) pandemic has impacted the way we live, enjoy, study, sport, and socialize significantly. Virtual reality fitness technology gained much attention during the COVID-19 preventive measures time. Objective: The present study explores the role of virtual reality fitness in improving overall wellbeing during the COVID-19 pandemic home isolation period in terms of physical-psychological health and physical activity. Methods: A total of 2300 individuals were recruited using the snowball sampling technique to participate in the study. The primary data were collected using an anonymous web-based survey. SPSS-23 and Smart-PLS 3.2.9 software were used to analyze the data. Results: The direct path coefficient analysis of the study constructs show that virtual reality fitness has (preventive measures -> virtual reality fitness -> overall wellbeing, preventive measures -> virtual reality fitness -> physical exercise, and preventive measures -> virtual reality fitness -> physical health) profound effects on the research participants' mental and physical wellbeing of the study participants while indirect mediation analysis shows that virtual reality fitness has (preventive measures -> virtual reality fitness ->overall wellbeing, preventive measures -> virtual reality fitness -> physical exercise, preventive measures -> virtual reality fitness ->physical health) significant impacts. Conclusion: Our study results concluded that house exercises through virtual reality fitness are a good substitute for public gyms and private group fitness programs during the first pandemic wave for physical-psychological and overall wellbeing. Virtual reality fitness technology can alleviate many of the challenges brought on by the epidemic, resulting in increased utilization.

Morphometric measurement of lower lumbar intervertebral foramina based on digital three-dimensional simulation.

AIM: This study aimed to investigate the morphology of the lower lumbar intervertebral foramina through use of a digital three-dimensional (3D) simulation model to guide the endoscope through the intervertebral foramina. MATERIAL AND METHODS: Individuals without disease affecting the lumbar vertebrae underwent computed tomography (CT) scanning in the supine position. The CT images obtained were imported to medical software to reconstruct a 3D model of the lumbar vertebrae. The stereoscopic longitudinal and transverse diameters of the lumbar intervertebral foramina were measured directly on the established simulation model. Comparisons in terms of sex and age were performed using t-test or analysis of variance. RESULTS: In total, 100 individuals were included in the study. Average longitudinal and transverse diameters of the lower lumbar intervertebral foramen decreased moving inferiorly. The longitudinal and transverse diameters of the lower lumbar intervertebral foramina were similar between sexes and between age groups. However, longitudinal diameter decreased with age (P 0.05). CONCLUSION: The reconstructed lumbar vertebrae simulation model presented in this study has high fidelity to the structure of the human lumbar spine. This approach provides individualized, accurate, standardized, and detailed guidance for endoscopic surgery through the lumbar intervertebral foramen.

Correlation of bone fragments reposition and related parameters in thoracolumbar burst fractures patients.

The aim of this study is to determine if thoracolumbar vertebral body collapse or canal compromise (CC) is associated with reposition of bone fragment. We retrospective review medical charts of patients with thoracolumbar burst fractures from July 2010 to September 2013. The fractures were classified according to the Arbeit Fuer Osteoosynthese (AO) classification system. Neurological status was classified according to American Spinal Injury Association (ASIA). Patients were divided into two groups (reposition group and non-reposition group) according to whether the bone fragments were reposition or non-reposition after surgery. Mimics measured mid-sagittal canal diameter (MSD), transverse canal diameter (TCD), local kyphosis (LK) and calculated anterior vertebral body compression ratio (AVBCR), middle vertebral body compression ratio (MVBCR), posterior vertebral body compression ratio (PVBCR), and mid-sagittal canal diameter compression ratio (MSDCR) on the preoperative CT image. The results indicated that 55 patients were included in the study. There are 35 patients with reposition of bone fragment and 20 patients with non-reposition of bone fragment after surgery. There were significant difference on MSD (t = 3.258, P = 0.002), TCD (t = 2.197, P = 0.032), AVBCR (t = -2.063, P = 0.044), MVBCR (t = -2.526, P = 0.015), PVBCR (t = -2.211, P = 0.031), MSDCR (t = -4.975, P = 0.000) between two groups before surgery. There was a significant correlation between reposition of bone fragment and AO classification (OR = 5.251, P = 0.022), and MSDCR (OR = 7.366, P = 0.007). There was no significant correlation between reposition and AVBCR, MVBCR, PVBCR, LK, MSD and TCD. In conclusion, this study indicates that AO classification and MSDCR are predictors of reposition of bone fragment.

Heavy-fermion quantum criticality and destruction of the Kondo effect in a nickel oxypnictide.

A quantum critical point arises at a continuous transformation between distinct phases of matter at zero temperature. Studies in antiferromagnetic heavy-fermion materials have revealed that quantum criticality has several classes, with an unconventional type that involves a critical destruction of the Kondo entanglement. To understand such varieties, it is important to extend the materials basis beyond the usual setting of intermetallic compounds. Here we show that a nickel oxypnictide, CeNiAsO, exhibits a heavy-fermion antiferromagnetic quantum critical point as a function of either pressure or P/As substitution. At the quantum critical point, non-Fermi-liquid behaviour appears, which is accompanied by a divergent effective carrier mass. Across the quantum critical point, the low-temperature Hall coefficient undergoes a rapid sign change, suggesting a sudden jump of the Fermi surface and a destruction of the Kondo effect. Our results imply that the enormous materials basis for the oxypnictides, which has been so crucial in the search for high-temperature superconductivity, will also play a vital role in the effort to establish the universality classes of quantum criticality in strongly correlated electron systems.

[Studies on the interaction between malanin and metal ions by fluorescence spectra methods].

A novel protein with anti-tumor activities named malanin was isolated and purified from an endemic plant in Yunnan and Guangxi provinces. Effects of copper ion, silver ion and calcium ion on malanin and apo-malanin fluorescence spectra were studied. The results showed that copper ion leads to obvious statistic quenching of malanin and apo-malanin fluorescence. The dissociation constant of them from malanin and apo-malanin were about 2.37 X 10(-4) and 2.66 X 10(-4) mol · L(-1), respectively. The silver ion did not have quenching action on malanin fluorescence, but it had statistic quenching effect on apo-malanin fluorescence, and its dissociation constant was 2.37 X 10(-4) mol · L(-1). Calcium ion did not have quenching action on malanin and apo-malanin fluorescence. It plays an important role in keeping malanin natural conformation.

Pressure-driven quantum criticality in iron-selenide superconductors.

We report a finding of a pressure-induced quantum critical transition in K0.8Fe(x)Se2 (x = 1.7 and 1.78) superconductors through in situ high-pressure electrical transport and x-ray diffraction measurements in diamond anvil cells. Transitions from metallic Fermi liquid behavior to non-Fermi liquid behavior and from antiferromagnetism to paramagnetism are found in the pressure range of 9.2-10.3 GPa, in which superconductivity tends to disappear. The change around the quantum critical point from the coexisting antiferromagnetism state and the Fermi liquid behavior to the paramagnetism state and the non-Fermi liquid behavior in the iron-selenide superconductors demonstrates a unique mechanism for their quantum critical transition.

[Metrx quadrant system in the surgery of lumbar spondylolisthesis: preliminary clinical application].

OBJECTIVE: To evaluate the clinical efficacy and minimal invasiveness of quadrant posterior distraction system in the posterior lumbar spondylolisthesis (LS) surgery. METHODS: Sixty-one LS patients were randomly divided into two groups: quadrant posterior minimally invasive surgery system as invasive group (n = 30) and traditional open surgery as open group (n = 31). The clinical outcome of pain relief was assessed by the scoring systems of visual analogue scale (VAS) and Oswestry disability index (ODI) for low back pain. Radiographic assessment: preoperative and 1-day, 3-month and last follow-up (12 months) radiographs were analyzed including the index of relative posterior disc height. RESULTS: The scores of VAS and ODI of invasive group were less than open group at Months 3 and 12 post-operation (P < 0.01). Relative posterior disc height of intra-operation and Month 3 was not significantly different (P > 0.05). And there was only statistical significance difference within 12 months (P < 0.05). At Month 12 post-operation, the fluctuating rate was slight. CONCLUSION: The minimally invasive operation with Quadrant is less traumatic to the patients than traditional open operation in the protection of spinal stability, postoperative rehabilitation and radiographs. This new minimally invasive spine technique should be popularized.

Band narrowing and Mott localization in iron oxychalcogenides La2O2Fe2O(Se,S)2.

Bad metal properties have motivated a description of the parent iron pnictides as correlated metals on the verge of Mott localization. What has been unclear is whether interactions can push these and related compounds to the Mott-insulating side of the phase diagram. Here we consider the iron oxychalcogenides La2O2Fe2O(Se,S)2, which contain an Fe square lattice with an expanded unit cell. We show theoretically that they contain enhanced correlation effects through band narrowing compared to LaOFeAs, and we provide experimental evidence that they are Mott insulators with moderate charge gaps. We also discuss the magnetic properties in terms of a Heisenberg model with frustrating J1-J2-J2' exchange interactions on a "doubled" checkerboard lattice.

[Experimental study of reservation flaval ligament on prevention of peridural adhesion after operation on lumbar disc].

OBJECTIVE: Through an experiment in rabbits, to evaluate the role of reservation flaval ligament using different methods to prevent the epidural adhesion by observing the morphological changes and provide experiment evidences for clinic. METHODS: 45 adult rabbits were divided into three groups: Group A (treated with no reservation of flaval ligament), Group B (treated with reserving half flaval ligament), and Group C (treated with reserving the complete flaval ligament). Every group has 15 rabbits. At the 2nd, 4th and 8th weeks, the samples were obtained for gross observation, histological examinations, and the images were analysed by computer. The data were processed using SPSS11.5. RESULT: Gross Observation and Histological Examinations, at the 2nd, 4th and 8th postoperative week, there was significant difference between the group A, B and C (gross observation: F2w=4.660, F4w=8.591, F8w=31.858, P<0.05; histological examinations: F2w=5.190, F4w=9.561, F8w=34.658, P<0.05). Images analysis: the difference was very significant in the groups at 2nd, 4th and 8th weeks (F2w=30.783, F4w=47.350, F8w=25.544, P<0.01). With time passing, the ratio became larger and larger in the same group. CONCLUSIONS: Reserving the complete flaval ligament can significantly prevent the peridural adhesion from the back as a barrier, and can reduce the adhesion formed.

Iron pnictides as a new setting for quantum criticality.

Two major themes in the physics of condensed matter are quantum critical phenomena and unconventional superconductivity. These usually occur in the context of competing interactions in systems of strongly correlated electrons. All this interesting physics comes together in the behavior of the recently discovered iron pnictide compounds that have generated enormous interest because of their moderately high-temperature superconductivity. The ubiquity of antiferromagnetic ordering in their phase diagrams naturally raises the question of the relevance of magnetic quantum criticality, but the answer remains uncertain both theoretically and experimentally. Here, we show that the undoped iron pnictides feature a unique type of magnetic quantum critical point, which results from a competition between electronic localization and itinerancy. Our theory provides a mechanism to understand the experimentally observed variation of the ordered moment among the undoped iron pnictides. We suggest P substitution for As in the undoped iron pnictides as a means to access this example of magnetic quantum criticality in an unmasked fashion. Our findings point to the iron pnictides as a much-needed setting for quantum criticality, one that offers a unique set of control parameters.

[Prevention of dura adherence in spinal canal after microendoscopic discectomy by different methods: a clinical study of 165 cases].

OBJECTIVE: To evaluate the effects of different methods in prevention of post-operational scar formation and dura adherence in the spinal canal after microendoscopic discectomy (MED). METHODS: 165 patients undergoing MED were randomly divided into 3 equal groups: Group A, with the yellow ligament dissected and with the space between vertebral laminae sprinkled with sodium hyaluronate before the closing of the incision; Group B, with the yellow ligament reserved; and Group C, with the yellow ligament reserved and with the space between vertebral laminae sprinkled with sodium hyaluronate before the closing of the incision. All the patients were followed up 2, 4, and 8 weeks, and 1 and 2 years after the operation. Japanese Orthopedic Association (JOA) scoring system was used to evaluate the outcomes. RESULTS: The JOA scores 2 weeks after MED were not significantly different among the 3 groups; and from then on the JOA scores of Groups B and C were all higher than those of group A (A and B: t(4w) = 0.602, t(8w) = 0.701, t(1y) = 0.623, t(2y) = 0.654; A and C: t(4w) = 0.833, t(8w) = 0.759, t(1y) = 0.714, t(2y) = 0.771, all P < 0.05), however, there were not significantly differences at all time points between Groups B and C (B and C: t(2w) = 0.041, t(4w) = 0.135, t(8w) = 0.980, t(1y) = 0.530, t(2y) = 0.103, all P > 0.05). CT showed that a great amount of scar was seen, surrounding the dura mater sac and nerve roots in Group A, and there was a great amount of scar outside the yellow ligament and no remarkable compression of dura mater sac and nerve roots in Groups B and C. CONCLUSION: Reservation of yellow ligament effectively prevents scar adhesion inside the vertebral canal after MED. Sprinkling of sodium hyaluronate is also effective, however, its effect only lasts a short time.