Silk fibroin fibers-based shape memory membrane with Janus wettability for multitiered wearable protection.

Realizing breathable shape memory fiber-based material with antibacterial and waterproof performances is important for multitiered wearable protection to address the increasing concerns of air pollution. Herein, using an alternating electrospinning-electrospraying technology, we develop a fiber-based membrane with Janus wettability based on a silk fibroin nanofibers-substrate (SFNFs), a polyurethane nanospheres-top layer (PUNSs), and a middle layer of PU nanofibers-mat with in-situ grown silver nanoparticles (PUNFs-AgNPs), which serves separately for skin contact, a self-cleaning physical barrier to resist external aerosol/bacteria (PM2.5 filtration efficiency ~ 98.1%), and a bio-barrier that can sterilize harmful particles and inhibit bacteria proliferation (> 95%). This breathable Janus film (SFNFs/PUNFs-AgNPs/PUNSs, SPAP) with an antibacterial filter shows shape memory stretchability enabled by the thermoplastic PU component, which is mechanically adaptive to human body for wearable protection. This work presents a breathable wearable material for air-filtration and anti-bacteria, promising for applications such as wound dressings, medical masks, protection suits, and multifunctional filters. Graphical abstract: An alternating electrospinning-electrospraying technology was proposed to achieve a silk fibroin-based antibacterial membrane with Janus wettability, as well as good skin affinity and breathability, which serves well as physical and bio-barriers for water resistance, PM2.5 filtration (~98.1%) and bacteria inhibition (efficiency of 95%). This shape memory Janus membrane can adapt mechanically to human body curvatures for functional wearable protections. Supplementary Information: The online version contains supplementary material available at 10.1557/s43578-022-00805-w.

Could extended laminectomy effectively prevent spinal cord injury due to spinal shortening after 3-column osteotomy?

OBJECTIVE: To explore whether the laminectomy extension can effectively prevent spinal cord injury (SCI) due to spinal shortening after 3-column osteotomy in goat models. METHODS: A total of twenty healthy goats were included and done with 3-column osteotomy of T13 and L1 under the somatosensory evoked potential (SSEP) monitoring. The samples were divided into two groups. The first group underwent regular laminectomy while the second group underwent an extended laminectomy with an extra 10 mm-lamina cranial to L2. The SSEP measured after 3-column osteotomy was set as the baseline, and the SSEP decreased by 50% from the baseline amplitude and/or delayed by 10% relative to the baseline peak latency was set as positive results, which indicated spinal cord injury. The vertebral column was gradually shortened until the SSEP monitoring just did not show a positive result. The height of the initial osteotomy gap (the distance from the lower endplate of T12 to the upper endplate of L2), the shortened distance (△H), the number of spinal cord angulated and the changed angle of the spinal cord (△α) were measured and recorded in each group. Neurological function was evaluated by the Tarlov scores on day 2 postoperatively. RESULTS: All the goats except one of the first group due to changes in the SSEP during the osteotomy were included and analyzed. In the first group, the height of the initial osteotomy segment and the safe shortening distances were 61.6 ± 2.6 mm and 35.2 ± 2.6 mm, respectively; the spinal cord of 5 goats was angulated (46.4 ± 6.6°), the other four goats were kinked and not angulated. In the second group, the height of the initial osteotomy segment and the safe shortening distances were 59.8 ± 1.5 mm and 43.3 ± 1.2 mm, respectively, and the spinal cord of ten goats were angulated (97.6 ± 7.2°). There was no significant difference in the height of the initial osteotomy segment between the two groups by using Independent-Samples T-Test, P = 0.095 (P > 0.05); there were significant difference in the safe shortening distance and the changed angle of the spinal cord between the two groups by using Independent-Samples T-Test (both [Formula: see text]H and [Formula: see text]α of P < 0.001), the difference between their mean were 8.1 mm and 51.2°. Significant difference was found in the number of spinal cord angulation between the two groups through Fisher's exact test (5/9 vs. 10/10, P = 0.033). CONCLUSIONS: An additional resection of 10 mm-lamina cranial to L2 showed the satisfactory effect in alleviating SCI after 3-column osteotomy. Timely and appropriate extend laminectomy could be a promising therapeutic strategy for SCI attributable to facilitating spinal cord angulation rather than spinal cord kinking and increasing the safe shortening distance.

Anterior reduction and C1-ring osteosynthesis with Jefferson-fracture reduction plate (JeRP) via transoral approach for unstable atlas fractures.

BACKGROUND: To introduce a novel transoral instrumentation in the treatment of unstable fractures of the atlas. METHODS: From January 2008 to May 2018, 22 patients with unstable C1 fractures who received Jefferson-fracture reduction plate (JeRP) via transoral approach were retrospectively analyzed. The case history and the radiographs before and after surgery were noted. The type of fracture, the reduction of the fracture, and position of the internal fixation were assessed through preoperative and postoperative CT scans. RESULTS: All 22 patients successfully underwent anterior C1-ring osteosynthesis using the JeRP system, with a follow-up of 26.84 ± 9.23 months. Among them, 9 patients had transverse atlantal ligament (TAL) injury, including 3 in Dickman type I and 6 in type II. The preoperative lateral mass displacement (LMD) decreased from 7.13 ± 1.46 mm to 1.02 ± 0.65 mm after the operation. Bone union was achieved in all patients without implant failure or loss of reduction. There were no surgery-related complications, such as wound infection, neurological deficit, or vertebral artery injury. However, atlantoaxial dislocation occurred in 3 patients with Dickman type I TAL injury 3 months postoperatively without any neurological symptoms or neck pain. CONCLUSIONS: Transoral C1-ring osteosynthesis with JeRP is an effective surgical strategy to treat unstable atlas fractures with a safe, direct, and satisfactory reduction. The primary indication for the JeRP system is an unstable fracture (Gehweiler type I/III) or/ and TAL injury (Dickman type II).

A Chemistry and Microstructure Perspective on Ion-Conducting Membranes for Redox Flow Batteries.

Redox flow batteries (RFBs) are among the most promising grid-scale energy storage technologies. However, the development of RFBs with high round-trip efficiency, high rate capability, and long cycle life for practical applications is highly restricted by the lack of appropriate ion-conducting membranes. Promising RFB membranes should separate positive and negative species completely and conduct balancing ions smoothly. Specific systems must meet additional requirements, such as high chemical stability in corrosive electrolytes, good resistance to organic solvents in nonaqueous systems, and excellent mechanical strength and flexibility. These rigorous requirements put high demands on the membrane design, essentially the chemistry and microstructure associated with ion transport channels. In this Review, we summarize the design rationale of recently reported RFB membranes at the molecular level, with an emphasis on new chemistry, novel microstructures, and innovative fabrication strategies. Future challenges and potential research opportunities within this field are also discussed.

Relationship between the laminectomy extension and spinal cord injury caused by acute spinal shortening: goat in vivo experiment.

OBJECTIVE: To investigate the relationship between different types of laminectomy extension and spinal cord injury subsequent to acute spinal shorting after 3-column osteotomy in living goat model. METHODS: A total of 18 healthy goats were selected, and a procedure of bivertebral column resections and total laminectomy of T13 and L1 was completed followed by different laminectomy extensions under the somatosensory evoked potential (SSEP) monitoring. The samples were divided into three groups according to types of subsequent laminectomy extension. In the first group (enlarged resection of upper lamina group), laminectomy extension was performed on 10 mm caudal to T12; in the second group (equidistant enlarged resection of upper and lower lamina group), laminectomy extension was performed on 5 mm caudal to T12 and 5 mm cranial to L2 simultaneously; and in the third group (enlarged resection of lower lamina group), laminectomy extension was performed on 10 mm cranial to L2. The SSEP measured after vertebral resection was set as the baseline, and the SSEP decreased by 50% from the baseline amplitude and/or delayed by 10% relative to the baseline peak latency was set as positive results, which indicated spinal cord injury. Spinal column was gradually shortened until the SSEP monitoring just did not show a positive result. The shortened distance (ΔH) and the changed angle of the spinal cord buckling (Δα) were measured in each group. Neurologic function was recorded by the Tarlov scores at 2 days after the surgery. RESULTS: The safe shortening distances of three groups were 38.6 ± 1.2 mm, 41.5 ± 0.7 mm, 43.7 ± 0.8 mm, respectively; the corresponding changed angles of the spinal cord buckling were 62.8 ± 6.9°, 82.8 ± 7.5°, and 98.5 ± 7.0°. Significant differences of ΔH and Δα were found among the three groups by LSD multiple comparison test (P < 0.05). Strong correlation between ΔH and Δα was shown in each group by Pearson's correlation test. CONCLUSIONS: Different laminectomy extensions after 3-column osteotomy have different effects on the prevention of SCI caused by acute spinal shortening. The enlarged resection of lower lamina is superior to equidistant enlarged resection of upper and lower laminas which is superior to enlarged resection of upper lamina in preventing SCI. These slides can be retrieved under Electronic Supplementary Material.

Transoral intraarticular cage distraction and C-JAWS fixation for revision of basilar invagination with irreducible atlantoaxial dislocation.

BACKGROUND: The revision surgery of basilar invagination (BI) with irreducible atlantoaxial dislocation (IAAD) after a previous occipitocervical fusion (OCF) is challenging. Transoral revision surgery has more advantages than a combined anterior and posterior approach in addressing this pathology. The C-JAWS is a cervical compressive staple that has been used in the lower cervical spine with many advantages. Up to now, there is no report on the application of C-JAWS in the atlantoaxial joint. We therefore present this report to investigate the clinical outcomes of transoral intraarticular cage distraction and C-JAWS fixation for revision of BI with IAAD. METHODS: From June 2011 to June 2015, 9 patients with BI and IAAD were revised by this technique after previous posterior OCF in our department. Plain cervical radiographs, computed tomographic scans and magnetic resonance imaging were obtained pre- and postoperatively to assess the degree of atlantoaxial dislocation and compression of the cervical cord. The Japanese Orthopedic Association (JOA) score was used to evaluate the neurological function. RESULTS: The revision surgeries were successfully performed in all patients. The average follow-up duration was 18.9 ± 7.3 months (range 9-30 months). The postoperative atlas-dens interval (ADI), cervicomedullary angle (CMA), distance between the top of the odontoid process and the Chamberlain line (CL) and JOA score were significantly improved in all patients (P < 0.05). Bony fusion was achieved after 3-9 months in all cases. No patients developed recurrent atlantoaxial instability. CONCLUSIONS: Transoral revision surgery by intraarticular cage distraction and C-JAWS fixation could provide a satisfactory outcome for BI with IAAD after a previous unsuccessful posterior operation.

Surgical treatment for basilar invagination with irreducible atlantoaxial dislocation: transoral atlantoaxial reduction plate fixation vs occipitocervical fixation.

BACKGROUND: Transoral atlantoaxial reduction plate (TARP) fixation or occipitocervical fixation (OF) is an effective treatment for basilar invagination (BI) with irreducible atlantoaxial dislocation (IAAD). But, all current clinical studies involved a single surgical procedure. The clinical effects of TARP and OF operation for BI with IAAD have yet to be compared. We therefore present this report to compare the treatment of TARP and OF procedure for BI with IAAD. METHODS: Fifty-six patients with BI with IAAD who underwent TARP or OF operation from June 2011 to June 2017 were retrospectively analyzed. Among these, 35 patients underwent TARP operation (TARP group), and 21 patients underwent OF operation (OF group). We compared the difference of clinical, radiological, and surgical outcomes between the TARP and OF groups postoperatively. RESULTS: Compared with OF group, the operative time and blood loss in TARP group were lower. There was no statistical difference in the atlantodental interval (ADI), clivus canal angle (CCA), cervicomedullary angle (CMA), distance between the top of the odontoid process and the Chamberlain line (CL) and Japanese Orthopaedic Association (JOA) score between the TARP and OF groups preoperatively, but the improvements of these parameters in the TARP group were superior to those in the OF group postoperatively. The fusion rates were higher in the TARP group than those in the OF group at the early stage postoperatively. CONCLUSIONS: TARP and OF operations are effective surgical treatment for BI with IAAD, but the performance of reduction and decompression and earlier bone fusion rates of TARP procedure are superior to those of OF.

Motion-preserving treatment of unstable atlas fracture: transoral anterior C1-ring osteosynthesis using a laminoplasty plate.

BACKGROUND: C1-ring osteosynthesis is a valid alternative to posterior C1-C2 or C0-C2 fusion to preserve important C1-C2 motion in the treatment of unstable atlas fractures. Nevertheless, the fixation instruments used in current studies for transoral anterior C1-ring osteosynthesis were not suitable for anterior anatomy of the atlas or did not have reduction mechanism. We therefore present this report to investigate preliminary clinical effects of transoral anterior C1-ring osteosynthesis using a laminoplasty plate in unstable atlas fractures. METHODS: From January 2014 to December 2017, 13 patients with unstable atlas fractures were retrospectively reviewed. All patients were treated with transoral anterior C1-ring osteosynthesis using a laminoplasty plate. Pre- and postoperative images were obtained to assess reduction of the fracture, internal fixation placement, and bone union. Neurological function, range of motion, and pain levels were evaluated clinically on follow-up. RESULTS: The surgeries were successfully performed in all cases. The average follow-up duration was 16.6 ± 4.4 months (range 12-24 months). One patient suffered screw loosening after operation and underwent replacement operation subsequently. Satisfactory clinical outcomes were achieved in all patients with ideal fracture reduction, reliable plate placement, well-preserved range of motion, and neck pain alleviation. All patients achieved bone union of fractures without loss of reduction or implant failure or C1-C2 instability during the follow-up. No vascular or neurological complication was noted during the operation and follow-up. CONCLUSIONS: Transoral anterior C1-ring osteosynthesis using a laminoplasty plate is a effective surgical treatment for unstable atlas fractures. This technique has a ingenious reduction mechanism, and can provide satisfactory bone union and preservation of C1-C2 motion.

Herbal Medicine-Derived Exosome-Like Nanovesicles: A Rising Star in Cancer Therapy.

Plant-derived exosome-like nanovesicles (PDNVs) are small nanoscale vesicles containing lipids, RNAs, proteins and some plant natural products secreted by plant cells. Over the last decade, PDNVs have garnered significant interest due to its exceptional therapeutic benefits in the treatment of various diseases. Herbal medicine, as a medicinal plant, plays an important role in the treatment of diseases including cancer. Especially in recent years, the function of herbal medicine derived exosome-like nanovesicles (HMDNVs) in the treatment of cancer has been widely concerned, and has become a research hotspot of nanomedicine. In this review, the biological characteristics, functions and the therapeutic advantages of PDNVs are reviewed, as well as the recent achievements and research progress of HMDNVs in cancer treatment, demonstrating its enormous promise as a cancer therapy, and new insights are provided for future research and development of anti-tumor drugs.

A Method to Evaluate the Reduction Difficulty of Atlantoaxial Dislocation Based on Computed Tomography Quantitative Analysis.

BACKGROUND: To evaluate the difficulty of reduction of congenital atlantoaxial dislocation with or without os odontoideum or basilar invagination based on computed tomography (CT) quantitative analysis. METHODS: From March 2018 to December 2022, the CT features of 108 patients with atlantoaxial dislocation with or without os odontoideum or basilar invagination were analyzed. Quantitative scores were defined according to imaging features, including sloping of the lateral mass; osteophyte between the lateral mass joint; ball-and-socket deformity of the lateral mass joint; vertical interlocking of the lateral mass joint; callus between the lateral mass joint; and atlanto-odontoid joint hyperplasia, blocking, or fusion. Grades were calculated according to the sum of points of the atlanto-odontoid joint and lateral mass joints, as follows: I, 0-1 points; Ⅱ, 2-3 points; Ⅲ, 4-6 points; IV, 7-10 points. After 1 week of bidirectional cervical traction, CT scans were performed, and atlantodens interval and vertical distance from dens to Chamberlain line were measured. The vertical reduction rate, horizontal reduction rate, and overall reduction rate of atlantoaxial dislocation were calculated. RESULTS: The vertical distance from dens to Chamberlain line values after traction were significantly reduced compared with before traction, including grades I, II, III, and IV. The overall reduction rates were 85.1% ± 11.8%, 65.8% ± 8.3%, 45.0% ± 8.5%, and 38.4% ± 13.0% respectively, after 1 week of bidirectional cervical traction. CONCLUSIONS: The CT quantitative score system is an effective noninvasive evaluation to judge the reduction difficulty of atlantoaxial dislocation with or without os odontoideum or basilar invagination.

Genome-wide identification and expression analysis of the KCS gene family in soybean (Glycine max) reveal their potential roles in response to abiotic stress.

Very long chain fatty acids (VLCFAs) are fatty acids with chain lengths of 20 or more carbon atoms, which are the building blocks of various lipids that regulate developmental processes and plant stress responses. 3-ketoacyl-CoA synthase encoded by the KCS gene is the key rate-limiting enzyme in VLCFA biosynthesis, but the KCS gene family in soybean (Glycine max) has not been adequately studied thus far. In this study, 31 KCS genes (namely GmKCS1 - GmKCS31) were identified in the soybean genome, which are unevenly distributed on 14 chromosomes. These GmKCS genes could be phylogenetically classified into seven groups. A total of 27 paralogous GmKCS gene pairs were identified with their Ka/Ks ratios indicating that they had undergone purifying selection during soybean genome expansion. Cis-acting element analysis revealed that GmKCS promoters contained multiple hormone- and stress-responsive elements, indicating that GmKCS gene expression levels may be regulated by various developmental and environmental stimuli. Expression profiles derived from RNA-seq data and qRT-PCR experiments indicated that GmKCS genes were diversely expressed in different organs/tissues, and many GmKCS genes were found to be differentially expressed in the leaves under cold, heat, salt, and drought stresses, suggesting their critical role in soybean resistance to abiotic stress. These results provide fundamental information about the soybean KCS genes and will aid in their further functional elucidation and exploitation.

Silk Fabric Decorated with Thermo-Sensitive Hydrogel for Sustained Release of Paracetamol.

Paracetamol is a safe and widely used antipyretic and analgesic drug, however, with the drawbacks of gastrointestinal first-pass effect and short intervals of administration. Transdermal drug delivery system can effectively avoid the liver metabolism caused by excess oral ingestion of paracetamol. Herein, a silk fabric-based medical dressing decorated by a thermo-responsive hydrogel for sustained release of paracetamol is proposed. Genipin as a bio-safe cross-linker is applied to assist gelation of a thermo-responsive hydrogel system coupled with chitosan and glycerol-phosphate disodium salt around body temperature (37 °C), as well as densifying the microporous gel to improve mechanical strength. The in situ sol-gel transition enabled hydrogel well penetrate and coat the silk fabric, forming a hierarchical hydrogel structure capable of prolonging the sustained release of drug to 12 h, twice as long as a blank fabric. The silk fabric with a thin gel coating maintains a good water vapor transmission rate, compatible for skin contact application. The drug release properties can be tuned by regulating the genipin content and fabric braiding structure. The silk fabric dressing exhibits temperature-dependent instant release behavior within the first 2 h. The sustained release mechanism of paracetamol well matches with the Korsmeyer-Peppas model in a non-Fickian diffusion.

Tamsulosin alters the pharmacokinetics of metformin via inhibition of renal multidrug and toxin extrusion protein 1 and organic cation transporter 2 in rats.

Among the endocrine and metabolic disorders, type-2 diabetes mellitus (T2DM) and benign prostatic hyperplasia (BPH) are common progressive diseases related to aging. Metformin and tamsulosin as the first-choice drug for patients with T2DM and BPH, respectively, are often co-administered to male patients with T2DM and BPH. However, whether concomitantly administering metformin and tamsulosin leads to drug-drug interactions (DDIs) remains unclear. This study aimed to evaluate the effect of tamsulosin on the pharmacokinetics of metformin and explore the relevant underlying mechanism. The plasma, urine, and tissue concentrations of metformin were analyzed using HPLC, and metformin cell uptake was analyzed using LC-MS/MS. In addition, western blotting was used to investigate the expression of Oct1, Oct2, and Mate1. As demonstrated by comparison with metformin alone, tamsulosin significantly increased the area under concentration-time curves (AUC0-t), the maximum plasma concentration (Cmax) and the decreased 24 h cumulative urinary excretion of metformin after single or multiple-dose administration in rats, as well as increased the kidney tissue concentration of metformin after multiple-dose. In addition, tamsulosin treatment significantly inhibited the expression of Mate1 and Oct2 in rat kidneys, but Oct1 and Mate1 did not show a significant difference in the liver. Consistently, tamsulosin inhibited OCT2 and MATE1 expressions and decreased metformin uptake in HEK293 cells. Notably, serum LCA level in the co-administration group was increased by 34% and 39% after multiple-dose (7 and 14 consecutive days, respectively) administration compared to the metformin alone group. Altogether, our data suggest that tamsulosin could increase systemic exposure and reduce excretion of metformin via inhibiting Oct2 and Mate1-mediated transport cooperatively.

Outcome of Thoracic Column Antedisplacement and Fusion in Treatment of Thoracic Myelopathy Caused by Ossification of Posterior Longitudinal Ligament: A Case Series Study.

BACKGROUND: Up to date, surgical outcome of multilevel thoracic ossification of posterior longitudinal ligament (T-OPLL) with high canal occupation ratio is less satisfactory. OBJECTIVE: To explore the result of thoracic column antedisplacement and fusion (TCAF) in treatment of multilevel T-OPLL with high canal occupation ratio. METHODS: A total of 5 patients who underwent TCAF procedure for T-OPLL were retrospectively reviewed. Parameters including extent of OPLL, thickness of the maximal OPLL (max-OPLL), maximal canal occupying ratio (max-COR) of OPLL, effective canal diameter (ECD) at the max-OPLL level, antedisplacement distance of thoracic columns, ASIA grades, Japanese Orthopedic Association (JOA) scores, and complications were collected and analyzed at preoperation and the last follow-up. RESULTS: All patients (5 F, mean age 61.0 yr, mean follow-up 18.0 months) underwent TCAF successfully and no spinal cord injury or cerebrospinal fluid leakage occurred. The mean extent of OPLL was 2.8 vertebral bodies. The mean preoperative thickness of the max-OPLL was 5.9 mm. The average antedisplacement distance of thoracic columns was 5.6 mm. The mean ECD was improved from 6.5 mm to 10.9 mm, and the max-COR was improved from 50.7% to 7.1% at last follow-up. Two patients showed improvement in ASIA grades and JOA scores were significantly improved from 5.6 points to 10.4 points at final follow-up. The overall therapeutic results of 1 patient were classified into good and 4 into fair at last follow-up. CONCLUSION: TCAF may be a safe and effective procedure in treatment of multilevel T-OPLL with high canal occupation ratio.

Anterior Transoral Débridement Combined with Posterior Fixation and Fusion for Atlantoaxial Tuberculosis.

BACKGROUND: Atlantoaxial tuberculosis (TB) is rare in clinical practice, accounting for only about 0.3%-1% of spinal TB. An anterior-only surgical approach cannot provide strong fixation, whereas a posterior approach cannot achieve complete removal of lesions. A method combining anterior and posterior approaches to treat atlantoaxial TB is advisable. The aim of this study was to evaluate the effectiveness of anterior transoral débridement combined with posterior fixation and fusion for atlantoaxial TB. METHODS: Clinical data of 20 patients with atlantoaxial TB who underwent anterior transoral débridement combined with posterior fixation and fusion in our hospital were retrospectively analyzed. Antituberculosis drugs were administered for 18 months after surgery. Neurologic status, clinical symptoms, fusion, reduction, and complications were evaluated. RESULTS: Surgeries were performed successfully in all 20 cases with no injuries to spinal cord, nerves, or blood vessels. Clinical symptoms were relieved in all 20 patients (100%). Postoperative Japanese Orthopaedic Association score, occipitocervical visual analog scale score, and atlantodental interval were significantly improved (P < 0.05). Average follow-up duration was 33 months (range, 24-48 months). Bony fusion was achieved in all 20 cases. No serious complications were documented during follow-up. CONCLUSIONS: Anterior transoral débridement combined with posterior fixation and fusion is an effective treatment for atlantoaxial TB, achieving removal of lesions and stability.

Safe Limit of Shortening of the Spinal Cord in Thoracolumbar Bivertebral Column Resections: An Experimental Study in Goats.

OBJECTIVE: To clarify the safe limit of shortening of the spinal cord in thoracolumbar bivertebral column resection in a goat model. METHODS: Ten healthy goats were selected for the experiment. Radiographs were taken before surgery to measure the height of T13, L1, and the initial osteotomy segment (distance from the lower end plate of T12 to the upper end plate of L2). A procedure of thoracolumbar bivertebral column resection (T13 and L1) was completed under the monitoring of somatosensory evoked potential (SSEP) monitoring. The SSEP measured after vertebral resection was set as the baseline. SSEPs decreased by 50% from the baseline amplitude and/or delayed by 10% relative to the baseline peak latency were set as positive results, indicating spinal cord injury. The initial height of the osteotomy gap was measured first and the spinal column was gradually shortened until the SSEP monitoring did not show a positive result. Then the height of the osteotomy gap was recorded again. The safe limit of shortening was measured and recorded when any morphologic change of the spinal cord was observed. Hindlimb function was evaluated by the Tarlov scores on day 2 postoperatively. RESULTS: The safe limit of shortening of the spinal cord in thoracolumbar bivertebral columns resection was 35.2 ± 2.6 mm, which was roughly equal to 127.6% of the mean osteotomy vertebral height and 57.1% of the initial osteotomy gap height. Pearson correlation test showed that the safe limit of shortening of the spinal cord was correlated with the height of T13, the height of L1, the mean height of T13 and L1, and the height of the initial osteotomy gap. CONCLUSIONS: The safe limit of shortening distance of the bivertebral column resection was roughly equal to 127.6% of the mean osteotomy vertebral height and 57.1% of the initial osteotomy gap height with good correlation. Moreover, the safe limit of shortening distance of the bivertebral column resection was longer than that in single vertebral column resection. Increasing the number of vertebrae resected may prevent spinal cord injury because of excessive shortening.

[Progress in treatment of unstable atlas fracture].

OBJECTIVE: To summarize the progress in treatment of unstable atlas fracture, the existing problems, and the research direction. METHODS: Related literature at home and abroad was reviewed. The stability evaluation of atlas fracture and treatment methods were introduced, and the selection of surgical approach and fixation instruments in treatment of unstable atlas fracture were summarized and analyzed. RESULTS: At present, atlas fractures are considered as unstable fractures except single anterior arch fractures with complete transverse ligament or simple posterior arch fractures. The treatment of unstable atlas fracture has been developed from nonsurgical treatment and traditional fusion surgery to single-segment fixation. Nonsurgical treatment is less effective, while traditional fusion surgery has a disadvantage of limited the motion of the upper cervical spine. Single-segment fixation can not only restore and fix the fracture, but also preserve the upper cervical motion function. Single-segment fixation approaches include posterior and transoral approaches, and the fixation instruments are being constantly improved, mainly including screw-rod system, screw-plate system, and plate system. CONCLUSION: For unstable atlas fracture, single-segment fixation is an ideal surgical method, and has more advantages when compared with nonsurgical treatment and traditional fusion surgery. Single-segment fixation via transoral approach is more direct for atlas anterior arch fracture reduction, but there is a high risk of infection; and single-segment fixation via posterior approach is less effective for the reduction of atlas anterior arch fracture. Therefore, a better reduction method should be explored.

Synthesis of TiO2NWS@AuNPS Composite Catalyst for Methylene Blue Removal.

In this article, HBP-NH2-modified titania nanowire (TiO2NWS)-decorated Au nanoparticles (TiO2NWS@AuNPS) were synthesized by one-step method. The role of HBP-NH2 concentration in the formation of TiO2NWS was investigated. The fineness and uniformity of pure TiO2NWS were enhanced by absorbed amino groups from amino-terminated hyperbranched polymer (HBP-NH2). The morphology and crystal structure of TiO2NWS and TiO2NWS@AuNPS were examined by transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fournier transform infrared (FTIR) spectroscopy. The chemical states of gold, titanium and oxygen were analyzed by X-ray photoelectron spectroscopy (XPS). The results showed that at the concentration of HBP-NH2 100 g/L, the mean diameter of TiO2NWS was nearly 72 nm and Au nanoparticles were uniformly distributed on the surface of TiO2NWS. The presence of AuNPS improved the photocatalytic properties of TiO2NWS under UV light irradiation. The Au load was believed to improve the utilization rate of the photoelectron and activated the adsorbed oxygen. The obtained TiO2NWS@AuNPS decomposed 99.6% methylene blue (MB) after 300 min when subjected to UV light irradiation. After five cycles of the catalyzing process, the TiO2NWS@AuNPS still retained over 90% of its catalytic ability for MB. The Au deposition was found responsible for the high catalytic activity of TiO2NWS@AuNPS.

One-Step Synthesis of Ag@TiO2 Nanoparticles for Enhanced Photocatalytic Performance.

Polyamide network polymers (PNP) modified TiO2 nanoparticles (NPs) were decorated with Ag NPs in hydrothermal gel method, forming one-step synthesized photocatalysts, Ag@TiO2 NPs. The effect of PNP and the amount of Ag NPs added were investigated in this work. PNP acted as a nanocage to prevent TiO2 aggregation and capture Ag accurately, which could effectively control product sizes and improve dispersibility in solvents. Simultaneously, TiO2 NPs modified with Ag NPs exhibited remarkable photocatalytic effects. One-step synthesis simplified the experimental process and avoided the agglomeration of silver ions during the secondary reaction, achieving the purpose of uniform distribution at a specific location of TiO2 NPs. The prepared Ag@TiO2 NPs-0.5 could remove 79.49% of Methyl Orange (MO) after 3 h of ultraviolet light irradiation, which was 2.7 times higher than the reaction rate of pure TiO2 NPs. It also exhibited good photoactivity under Visible light conditions. Moreover, the mineralization rate of MO over the Ag@TiO2 NPs-0.5 could be up to 72.32% under UV light and 47.08% under Visible light irradiation, which revealed that the prepared catalysts could effectively degrade most of the MO to CO2 and H2O. The samples also demonstrated the excellent stability and easy recyclability with over 90% of the original catalytic level for MO degradation. The photocatalysts studied also exerted broad application prospects such as photovoltaic hydrogen production, electronic sensors and biomedicine.