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Objective: The mainstream lumbar fusion surgeries have various shortcomings, such as complex operation, much invasion, and loss of lumbar function. How to minimize the surgical injury and to achieve better therapeutic effects has become the goal pursued by spine surgeons. This study introduces a cortical bone trajectory (CBT) screw fixation combined with facet fusion (FF), evaluates its safety and efficacy, and explores its advantages, in order to provide a reference for treatment of patients with single‐level lumbar stenosis or grade I degenerative spondylolisthesis. Methods: We retrospectively analyzed the clinical, radiological, and operative data of 167 patients with single‐level lumbar stenosis or grade I degenerative spondylolisthesis who underwent FF or transforaminal lumbar interbody fusion (TLIF) from January 2013 to September 2019 in the spine surgery department of the Second Hospital of Shandong University. Patients were divided into four groups according to surgical method: group CBT‐FF, CBT screw combined with FF; group PS‐FF, pedicle screw (PS) combined with FF; group CBT‐TLIF, CBT screw combined with TLIF; and group PS‐TLIF, PS combined with TLIF. The operation time, estimated intraoperative blood loss, complications after surgery, visual analog scale (VAS), and Oswestry disability index (ODI) of the four groups were compared. The fusion was evaluated by anteroposterior and lateral X‐ray, CT scan, and three‐dimensional reconstruction. Results: Twelve months after surgery, the fusion rate of four groups had no significantly statistical differences (p = 0.914). VAS and ODI scores were lower after surgery than before. Low back pain VAS scores 1 week after surgery in group CBT‐FF and group CBT‐TLIF were significantly lower than those in group PS‐FF and group PS‐TLIF (pCF/PF = 0.001, pCF/PT = 0.000, pPF/CT = 0.049, pCT/PT = 0.000). Low back pain VAS score 3 months after surgery was significantly lower in group CBT‐FF than group PS‐FF and group PS‐TLIF (pCF/PF = 0.045, pCF/PT = 0.008). ODI score 1 week after surgery was significantly lower in group CBT‐FF than group PS‐FF, group CBT‐TLIF, and group PS‐TLIF (pCF/PF = 0.000, pCF/CT = 0.005, pCF/PT = 0.000, pCT/PT = 0.015). ODI score 3 months after surgery was significantly lower in group CBT‐FF than group PS‐FF, group CBT‐TLIF, and group PS‐TLIF (pCF/PF = 0.001, pCF/CT = 0.002, pCF/PT = 0.000). Incidence of complications did not significantly differ among the groups. Conclusion: CBT screw fixation combined with FF is a safe and efficacious procedure for patients with single‐level lumbar stenosis or grade I degenerative spondylolisthesis. This minimally invasive approach of lumbar fusion can be simply and easily performed. Patients who undergo CBT screw fixation combined with FF recovered faster than TLIF. [ABSTRACT FROM AUTHOR]

The present examination includes manufacture and portrayal of cryogel bio-composite implants containing chitosan-gelatin (CS-GT), cerium–zinc doped hydroxyapatite (CS-GT/Ce-Zn-HA) by cryogelation technique. The prepared cryogel biocomposites (CS-GT/HA and CS-GT/Ce-Zn-HA) were described by scanning electron microscope (SEM) and X-Ray diffraction (XRD) contemplates. The expansion of Ce-Zn in the CS-GT implants essentially expanded growing, diminished swelling, expanded protein sorption, and expanded bactericidal movement. The CS-GT/Ce-Zn-HA biocomposite had non-toxic towards rodent osteoblast cells. So the created CS-GT/Ce-Zn-HA biocomposite has favorable and potential applications over the CS-GT/HA platforms for bone tissue engineering. [ABSTRACT FROM AUTHOR]

Concentration, spatial distribution, composition and sources of polycyclic aromatic hydrocarbons (PAHs) were investigated based on measurements of 16 PAH compounds in surface sediments of the western Taiwan Strait. Total PAH concentrations ranged from 2.41 to 218.54 ng g − 1 . Cluster analysis identified three site clusters representing the northern, central and southern regions. Sedimentary PAHs mainly originated from a mixture of pyrolytic and petrogenic in the north, from pyrolytic in the central, and from petrogenic in the south. An end-member mixing model was performed using PAH compound data to estimate mixing proportions for unknown end-members (i.e., extreme-value sample points) proposed by principal component analysis (PCA). The results showed that the analyzed samples can be expressed as mixtures of three end-members, and the mixing of different end-members was strongly related to the transport pathway controlled by two currents, which alternately prevail in the Taiwan Strait during different seasons. [ABSTRACT FROM AUTHOR]

The Lingdingyang Estuary is one of the most important estuaries in the Southern China. With the regional rapid industrialization and urbanization, the engineering geological environment at Lingdingyang Estuary has attracted growing attention. Total of 250 samples and about 1,420 km of high resolution seismic profiles were collected by the Guangzhou Marine Geology Survey (GMGS) in 2004 and 2005. First, the characteristics of engineering geological environment at Lingdingyang Estuary were studied regarding three aspects, including topography and morphology, shallow geology, the submarine soil types and its physical-mechanical properties. The characteristics of the topography and morphology, and the shallow geology in the Lingdingyang Estuary were studied based on the high resolution seismic profiles, whereas the sediments were used to derive the physical-mechanical properties of soil. Second, the soil stability and engineering geological areas are discussed. Finally, it is suggested that the study area can be divided into 2 regions: area I and area II. Area I can be further divided into 3 subdivisions: subarea I1, subareaI2 and subarea I3. [ABSTRACT FROM AUTHOR]

This paper presents a complete map of the Mesozoic volcanic-plutonic complexes in the Taiwan Strait and its adjacent areas in terms of seismic profiles, ages, geochemistry, isotopic systematics, and published data. Two periods of igneous activity in the Taiwan Strait can be distinguished by seismic profiles: Jurassic (200.4–148.2 Ma); and Latest Jurassic/Cretaceous to Maastrichtian (144–66 Ma), of which the Cretaceous is the best preserved and could possibly be the most widespread. Mesozoic magmatic activity with the NE-striking distribution was migrating southeastward (oceanward). LA-MC-ICPMS zircon U – Pb dating yields the age data of 109.5 ± 0.4 Ma for PTDH1 granodiorite and 92.6 ± 0.4 Ma for PTDH4 rhyolite in the Taiwan Strait, respectively. The 581.66-m-thick Upper Jurassic volcanic rocks of the Chuan2 well are the thickest Mesozoic igneous rocks in the Taiwan Strait. The petrogenetic discrimination diagram of the Cretaceous volcanic-plutonic complexes along the coast of South China and the Taiwan Strait generally is belonging to volcanic arc or intraplate type calc-alkaline rock series. The high potassium calc-alkaline rock series of the Cretaceous volcanic-plutonic complexes that is most widely distributed in the coastal areas of South China and the Taiwan Strait. They are controlled by the subduction of the Palaeo-Pacific domain. [ABSTRACT FROM AUTHOR]

Abstract Major and trace elemental concentrations in coastal marine sediments were incorporated into positive matrix factorization (PMF) to identify potential sources and source contributions. Transport pathways of fine-grained sediments and sediment-bound elements were inferred from sediment trend analysis (STA). The spatial distribution patterns of 21 elements (Co, Cu, Ni, Sr, Zn, V, Ba, Sc, Ga, Pb, Cr, Zr, SiO 2 , Al 2 O 3 , Fe 2 O 3 , MgO, CaO, K 2 O, MnO, TiO 2 , and P 2 O 5) coupled with sediment grain sizes were investigated. The natural and anthropogenic sources of the elements were distinguished by their medium enrichment factors (EFs). Seven sources were recognized by PMF: weathering products, anthropologic emissions, sand, older sediment, biogenic carbonates, products of siliceous organisms, and mine exploitation. Some land-derived elements, including weathering products, anthropogenic-related elements, and mining-related elements, had a significant positive correlation with sediment silt, clay, and organic carbon contents. The spatial patterns of the land-derived elements' concentrations and source contributions were consistent with the sediment transport pathways inferred from the STA. This result revealed that the delivery of the land-derived elements was determined by marine current flows and the associated sediment transport processes. Conversely, elements originating from marine sources, such as sand and older sediment, and from the biological activities of calcareous and siliceous organisms showed little response to sediment transport and deposition processes. Our study links the outputs of statistically oriented approaches (e.g., PMF) to a process-based understanding of elemental transport in marine environments. Graphical abstract Unlabelled Image Highlights • Elemental concentrations and enrichment were assessed in coastal marine sediments. • PMF was used for source apportionment and seven potential sources were identified. • Net sediment transport patterns were established using the STA model. • Patterns of elements' contribution coincide with source-to-sink transport processes. • Transport of sediment as well as elements is interpreted in terms of hydrodynamics. [ABSTRACT FROM AUTHOR]

Self-organizing map (SOM) was used to explore the spatial characteristics of water quality in the middle and southern Fujian coastal area. Nineteen water quality variables (temperature, salinity, pH, dissolved oxygen, alkalinity, chemical oxygen demand, nutrients NH 4 -N, H 2 SiO 3 , PO 4 − , NO 2 − , and NO 3 − , heavy metals/metalloid Cu, Zn, As, Cd, Pb, Hg, and Cr 6+ , and oil) were measured in the surface, middle, and bottom water layers at 94 different sampling sites. Patterns of water quality variables were visualized by the SOM planes, and similar patterns were observed for those variables that correlated with each other, indicating a common source. pH, COD, As, Hg, Pb, and Cr 6+ likely originated from industries, while nutrients NH 4 -N, NO 2 − , NO 3 − , and PO 4 3− were mainly attributed to agriculture and aquaculture. The k-means clustering in the SOM grouped the water quality data into nine clusters, which revealed three representative water types, ranging from low salinity to high salinity with different levels of heavy metal/metalloid pollution and nutrient pollution. Spatial changes in water quality reflected the impacts of natural factors (riverine outflows, tides, and alongshore currents), as well as anthropogenic activities (mariculture, industrial and urban discharges, and agricultural effluents). Principal component analysis (PCA) confirmed the clustering results obtained by SOM, while the latter provides a more detailed classification and additional information about the dominant variables governing the classification processes. The results of this study suggest that SOM is an effective tool for a better understanding of patterns and processes driving water quality. [ABSTRACT FROM AUTHOR]

Objective: The aim of the present study was to compare the long-term effects of posterior C1-ring osteosynthesis and C1-2 fixation fusion in the treatment of unstable atlas fractures., Methods: A multicenter, prospective, randomized controlled trial was conducted to analyze 73 patients with atlas fractures who underwent posterior fixation. The intervention group was treated with C1-ring osteosynthesis, and the control group was treated with C1-2 fixation fusion. The patients were followed up for 6 months, 1 year, 2 years, and 5 years after the operation., Results: Fifty-two patients had complete data at the last follow-up. The visual analog scale (VAS) score for neck pain in the intervention group was lower than that in the control group (p < 0.001). The operation time, intraoperative blood loss, radiation dose, bedridden period, hospital stay, and cost in the intervention group were significantly lower than those in the control group (p < 0.001). At the last follow-up, the Neck Disability Index in the intervention group was higher than that of the control group, and the angle of flexion-extension and axial rotation in the intervention group were greater than those in the control group (p < 0.001)., Conclusions: In this study, the authors found that posterior C1-ring osteosynthesis is superior to C1-2 fixation fusion in terms of long-term relief of neck pain and preservation of the physiological function of the cervical vertebrae. This technique is a reliable choice for the treatment of unstable C1 fractures.

The SS18-SSX1 fusion gene has been shown to play important roles in the development of synovial sarcoma (SS), but the underlying molecular mechanisms and its downstream target genes are still not clear. Here SHC SH2-domain binding protein 1 (SHCBP1) was identified and validated to be a novel downstream target gene of SS18-SSX1 by using microarray assay, quantitative real-time (qPCR) and western blot. Expression of SHCBP1 was firstly confirmed in SS cell line and SS tissues. The effects of SHCBP1 overexpression or knockdown on SS cell proliferation and tumorigenicity were then studied by cell proliferation, DNA replication, colony formation, flow cytometric assays, and its in vivo tumorigenesis was determined in the nude mice. Meanwhile, the related signaling pathways of SHCBP1 were also examined in SS cells. The results indicated that SHCBP1 was significantly increased in SS cells and SS tissues compared with adjacent noncancerous tissues. The expression of SHCBP1 was demonstrated to be positively correlated with the SS18-SSX1 level. Overexpression and ablation of SHCBP1 promoted and inhibited, respectively, the proliferation and tumorigenicity of SS cells in vitro. SHCBP1 knockdown also significantly inhibited SS cell growth in nude mice, and lowered the MAPK/ERK and PI3K/AKT/mTOR signaling pathways and cyclin D1 expression. Our findings disclose that SHCBP1 is a novel downstream target gene of SS18-SSX1, and demonstrate that the oncogene SS18-SSX1 promotes tumorigenesis by increasing the expression of SHCBP1, which normally acts as a tumor promoting factor.

Previous studies have suggested that impairment secondary to mechanical injury is a major cause of irreversible damage to the spinal cord. Inflammatory chemokines have been shown to play an important role in the pathological and physiological consequences of secondary spinal cord injury (SCI). The aim of the present study was to evaluate how changes in the expression levels of the cellular chemokine, monocyte chemoattractant peptide-1 (MCP-1), and the chemotaxis of inflammatory cells (monocytes and macrophages) are involved in the process of SCI. RNA interference methods were used to study the mechanisms that protect residual neurons after SCI in an attempt to explore novel, early interventions for managing SCI. Our results suggested that inhibiting inflammation alleviates nerve cell injury caused by apoptosis and provides a potentially important approach for the future treatment of secondary SCI.

Objective: To study the effects of fibrin sealant containing nerve growth factor on the peripheral nerve regeneration., Study Design: A four-group experimental design with repeated measures on one factor was used., Methods: Fibrin glue (FG) containing NGF was injected into the site of end-and-end sutured peripheral nerve (sciatic nerve) (group I: NGF+FG), meanwhile three control groups were set-up: group II (NGF), group III (FG), and group IV (normal saline). Observation to the function and morphology of the sciatic nerve was carried out at the end of 4, 8, 12 weeks postoperation. Data were analyzed using ANOVA, with the appropriate post hoc between-groups comparison test., Results: Electrophysiological testing. The NAP and NCV of group I (NGF+FG) were greater than those of group II (NGF), group III (FG), or group IV (normal saline) (p<0.05). Sciatic functional index (SFI). It began to ameliorate at 4 weeks postoperation and SFI increased as time went on. And the SFI in group I (NGF+FG) was better than those in group II (NGF), group III (FG), or group IV (normal saline) (p<0.05). Morphology. In the MGF-stained sections, dissociated myelin debris was less and regenerated nerve fibres were in larger quantities in group I (NGF+FG) than in other groups. In the HE-stained sections, regenerated nerve fibres distal to anastomosis significantly increased, and axon and myelin had a clearer outline in group I (NGF+FG) than in other groups. Electron microscopy indicated that the regenerated nerve fibres were more mature and the development of the axons was greater in group I than in other control groups., Conclusions: FG can be used as carrier of exogenous NGF, and they can provide synergistic effects for the peripheral nerve regeneration after the integration of the two.