Dendrobium viroid, a new monocot-infecting apscaviroid

Viroids are small circular RNA molecules which have been found to infect many dicot species. Only coconut cadang-cadang viroid and coconut tinangaja viroid have been reported so far to infect a monocot (coconut). Data mining in silico has proven an efficient approach to identify new viruses/viroids, and a systematic screen of public transcriptomic data revealed a 648 nucleotides (nt) sequence potentially representing a novel viroid-like RNA in a transcriptome shotgun assembly from Dendrobium officinale. This sequence contained two central conserved regions (CCRs) characteristic of members of the genus Apscaviroid, indicating that the viroid-like RNA is 324 nt in length. The infectivity of dimeric RNA transcripts generated by in vitro transcription of a synthetic cDNA, was demonstrated by directly injecting into the stems of young Dendrobium officinale plants. The presence of this novel viroid, tentatively designated as Dendrobium viroid (DVd), in the inoculated plants was confirmed by 2D-PAGE together with northern hybridization. DVd is predicted to have a rod-like secondary structure containing a CCR and a terminal conserved region (TCR), and phylogenetic analysis shows that it groups with the known members of the genus Apscaviroid. It is most closely related to citrus viroid V (56% nt identity). A field survey revealed a low DVd incidence (0.96%) in Dendrobium species in China. To our best knowledge, DVd is the only viroid known to infect orchids and the third one from monocotyledonous plants.

Chronic morphine-mediated upregulation of high mobility group box 1 in the spinal cord contributes to analgesic tolerance and hyperalgesia in rats

Analgesic tolerance and hyperalgesia hinder the long-term utility of opioids. We examined whether spinal high mobility group box 1 (HMGB1) is involved in morphine tolerance and its underlying mechanisms by using a model of repeated intrathecal (i.t.) injections of morphine. The results showed that chronic i.t. morphine exposure led to increased expression of HMGB1, Toll-like receptor 4 (TLR4), and receptor for advanced glycation end products (RAGE) and their mRNAs in the dorsal horn. Morphine challenge also promoted HMGB1 expression and release in cultured spinal neurons, but these effects were inhibited by TAK-242, naloxone (antagonists of TLR4), and TLR4 siRNA. Intrathecal coadministration of morphine with TAK-242 or PDTC (inhibitor of NF-κB activation) also reduced HMGB1 expression in the spinal cord. Repeated i.t. coinjections of morphine with glycyrrhizin (GL, an HMGB1 inhibitor) or HMGB1 siRNA prevented reduction of the maximal possible analgesic effect (MPAE) of morphine and alleviated morphine withdrawal-induced hyperalgesia. The established morphine tolerance and hyperalgesia were partially reversed when i.t. injections of GL or HMGB1 antibody started at day 7 of morphine injection. Repeated i.t. injections of morphine with HMGB1 siRNA inhibited the activation of NF-κB, but not that of JNK and p38. A single i.t. injection of HMGB1 in naïve rats caused pain-related hypersensitivity and reduction in MPAE. Moreover, phosphorylated NF-κB p65, TNF-α, and IL-1β levels in the dorsal horn were upregulated following this treatment, but this upregulation was prevented by coinjection with TAK-242. Together, these results suggest that morphine-mediated upregulation of spinal HMGB1 contributes to analgesic tolerance and hyperalgesia via activation of TLR4/NF-κB signaling, and the HMGB1 inhibitor might be a promising adjuvant to morphine in the treatment of intractable pain in the clinic.

2D graphdiyne: an excellent ultraviolet nonlinear absorption material

With an sp2-hybridized carbon atom structure, graphene is recognized as a nonlinear absorption (NLA) material, which has motivated scientists to explore new allotropes of carbon. Different from graphene, graphdiyne (GDY) consists of sp- and sp2-hybridized carbon atoms. An sp-hybridized carbon-carbon triple bond structure will bring in novel nonlinear optical properties, which are different from other allotropes of carbon. In this study, we investigated the broadband NLA properties (ultraviolet-infrared waveband) of GDY nanosheets, exfoliated using a liquid-phase exfoliation (LPE) method. The short ultraviolet cut-off wavelength (around 200 nm-220 nm) forebodes the potential application of GDY as an ultraviolet optical material. The outstanding NLA resulting in an ultraviolet waveband attests that the GDY nanosheets are veritable ultraviolet NLA materials, which have potential applications in ultraviolet optics. Our study broadens the application scopes of nanomaterials.

Outcome analysis of various bearing surface materials used in total hip replacement

Since the first total hip replacement (THR) in 1938 by Philip Wiles, prosthesis materials and THR surgical technologies have developed rapidly. In this review, we use internationally-published research to synthesize a comprehensive analysis of the specific characteristics and clinical outcomes of different bearing surfaces used in THR. Polyethylene, metallic alloys, and ceramic have become the three most commonly used hip prosthesis bearing surfaces after decades of hip implant development. Different bearing surface types have varying characteristics that offer specific benefits and risks of complication. A thorough understanding of the unique properties and possible complications of each type of bearing surface is critical to surgeons tasked with selecting appropriate implant materials for total hip replacement.

Review of Polarization Optical Devices Based on Graphene Materials

Graphene has received extensive scholarly attention for its extraordinary optical, electrical, and physicochemical properties, as well as its compatibility with silicon-based semiconductor processes. As a unique two-dimensional atomic crystal material, graphene has excellent mechanical properties, ultra-high carrier mobility, ultra-wide optical response spectrum, and strong polarization dependence effect, which make it have great potential in new optical and polarization devices. A series of new optical devices that are based on graphene have been developed, showing excellent performance and broad application prospects. In this paper, the recent research progress of polarizers, sensors, modulators, and detectors that are based on the polarization characteristics of graphene is reviewed. In particular, the polarization dependence effect and broadband absorption enhancement of graphene under total reflection structure are emphasized, which enhance the interaction between graphene and light and then provide a new direction for research of graphene polarization devices.

Effects of pulsed electromagnetic field therapy on pain, stiffness and physical function in patients with knee osteoarthritis: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To evaluate the efficacy of classical pulsed electromagnetic field therapy on patients with knee osteoarthritis.

METHODS

The databases PubMed, EMBASE, Web of Science and Cochrane Library were searched for relevant studies. Randomized controlled trials comparing classical pulsed electromagnetic field with placebo for patients with knee osteoarthritis were included. Data for primary outcomes, including pain, stiffness and physical function, were extracted. Data from 8 randomized controlled trials involving 421 patients were pooled.

RESULTS

Pulsed electromagnetic field therapy had an effect on improving physical function (weighted mean difference; WMD = -5.28, 95% confidence interval; 95% CI -9.45 to -1.11, p = 0.01), but showed no advantage in the reduction of Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) total score (WMD = -7.80, 95% CI -16.08 to 0.47, p = 0.06), WOMAC pain score (WMD = -1.06, 95% CI -2.30 to 0.17, p = 0.09), visual analogue scale pain score (WMD=-0.88, 95% CI -2.06 to 0.31, p = 0.15) or WOMAC stiffness score (WMD = -0.50, 95% CI -1.09 to 0.09, p = 0.1).

CONCLUSION

Pulsed electromagnetic field therapy is beneficial for improving physical function despite having no advantage in treating pain and stiffness. Further randomized controlled trials are needed to confirm these findings and determine the optimal parameters and treatment regimen for pulsed electromagnetic field therapy.

[Research progress in treatment of proximal humeral fracture with fibular allograft and locking plate]

Objective

To review the research progress in the treatment of proximal humeral fractures with fibular allograft and locking plate.

Methods

The literature about the treatment of proximal humeral fractures with fibular allograft and locking plate was reviewed and analyzed from the aspects such as the biomechanics, imaging prognosis, and clinical prognosis.

Results

Fibular allograft and locking plate can provide effective medial support for proximal humeral fracture and increase the strength of internal fixation system. Compared with locking plate, fibular allograft combined with locking plate can maintain better humeral neck-shaft angle and the humeral head height after operation in the treatment of proximal humeral fractures, and has better shoulder mobility and shoulder joint function, and does not increase the risk of complications.

Conclusion

Fibular allograft combined with locking plate may be a new and effective treatment for proximal humeral fractures. However, the long-term follow-up results are insufficient, the final outcome of fibula is uncertain, and the long-term potential adverse reactions caused by this treatment are still indefinite.

A sensitive, wide-ranging comprehensive toxicity indicator based on microbial fuel cell

An innovative indicator for toxicity detection based on microbial fuel cells, average current inhibition rate (ACIR) was proposed. It was applied to the toxicity evaluation of three typical specific pollutants in petrochemical wastewater including copper(II), 2,4-dichlorophenol (2,4-DCP) and pyridine. ACIR which considered the entire process of toxic effects was proved to be more sensitive and wide-ranging than the conventional indicators. The linear detection ranges were 0.3-100 mg/L of copper(II), 0.4-1000 mg/L of 2,4-DCP, and 0.1-1000 mg/L of pyridine. The median effective concentrations of the three toxicants were 34.32, 36.18 and above 1000 mg/L, respectively. By contrast, using a conventional indicator such as the voltage inhibition rate, the calculation results consistently change with the exposure time. Based on the response time, the toxicity will be difficult to distinguish under high concentrations. An analysis of the microbial community in anode chamber showed that electrogenic bacteria such as Geobacter and Arcobacter significantly decreased with 2,4-DCP and pyridine under all tested concentrations. A principal component analysis was conducted, the results of which showed that the microbial community shifted from left to right with the increase concentration of copper(II) and 2,4-DCP. An increase of ACIR was noticed to be in accordance with the reduction of electrogenic bacteria.

Postoperative outcomes of tranexamic acid use in geriatric trauma patients treated with proximal femoral intramedullary nails: A systematic review and meta-analysis

BACKGROUND

Recently, there has been a series of clinical studies focusing on the perioperative administration of tranexamic acid (TXA) in geriatric trauma patients undergoing proximal femoral intramedullary nail surgery. However, the safety and efficacy of TXA in these patients remains controversial. Therefore, we performed a systematic review to focus on two questions: (1) would TXA reduce perioperative blood loss in geriatric trauma patients undergoing proximal femoral intramedullary nail surgery? and (2) would TXA increase the rate of perioperative complications in geriatric trauma patients undergoing proximal femoral intramedullary nail surgery?

PATIENTS AND METHODS

We systematically searched electronic databases (MEDLINE, EMBASE, PubMed, and Cochrane Central Register of Controlled Trials) up to April 20, 2019. The perioperative blood loss and complication data were extracted and analysed by RevMan Manager 5.3.

RESULTS

Finally, five randomized controlled studies, involving 539 geriatric intertrochanteric fracture patients undergoing proximal femoral intramedullary nail surgery, were enrolled in this systematic review. Compared with the control group, the TXA group had significantly lower total perioperative blood loss (WMD=-172.84; 95% CI, -241.44 to -104.24; I²=0%), intraoperative blood loss (WMD=-34.20; 95% CI, -46.04 to -22.36; I²=0%), total perioperative hidden blood loss (WMD=-139.05; 95% CI, -213.67 to -64.43; I²=0%), perioperative transfusion rates (RR =-0.16; 95% CI, -0.24 to -0.08; I²=22%), length of hospital stay (WMD=-1.18; 95% CI, -1.91 to -0.46; p=0.001; I2=12%), and postoperative wound haematoma rates (RD=-0.05; 95% CI, -0.09 to 0.00; p=0.03; I²=0%). In addition, there were no significant differences between TXA and control groups in the terms of surgical time, postoperative mortality, total thromboembolic events, wound infections, cerebrovascular accidents, respiratory infections, and renal failure.

DISCUSSION

TXA in geriatric trauma patients undergoing intramedullary nail surgery is effective for perioperative haemostasis without increasing the incidence of postoperative complications.

LEVEL OF EVIDENCE

II, Systematic review and Meta-analysis.

[Observation of the therapeutic and characteristic effects of terlipressin on refractory cirrhotic ascites]

Objective: To observe the therapeutic effect of terlipressin on refractory ascites (RA) in cirrhosis, and its role and impact on acute kidney injury (AKI). Methods: A non-randomized controlled clinical trial data of 111 hospitalized cases of liver cirrhosis accompanied with RA was collected from Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Zhongshan Hospital of Hubei Province, The First Affiliated Hospital of Zhengzhou University, The First Affiliated Hospital of Medical School of Zhejiang University, and People's Hospital of Pudong New Area of Shanghai between March 2015 and March 2017. 26 cases of conventional treatment group (control group) were divided into two subgroups: RA without AKI (RA-NAKI) and RA with AKI (RA-AKI), and each subgroup consisted 13 cases. Patients with bacterial infection were treated with diuretics, albumin supplementation and antibiotics. 85 cases were presented in terlipressin combined treatment group, of which 27 cases were of RA-NAKI and 58 cases were of RA-AKI. Control group was injected terlipressin 1mg of intravenous drip or static push (once q6 h ~ 12 h) for more than 5 days. The treatment duration lasted for 2 weeks with 4 weeks of follow-up. Body weight, 24-hour urine volume, abdominal circumference, mean arterial pressure (MAP), liver and kidney function, anterior hepatic ascites, deepest point of ascites, and ultrasonographic detection of ascites in supine position before treatment, one and two weeks after treatment and 4 weeks after follow-up were compared. Count data were tested by χ (2). Samples of four groups at baseline were compared. One-way analysis of variance was used for normal distribution data and Kruskal-Wallis H test for non-normal distribution data. Repeated measures analysis of variance was used to compare the difference in efficacy between different time points before and after treatment in the group. The LSD method of one-way ANOVA was used to compare the two groups. A t-test of independent samples was used to compare the efficacy of different time series between the two groups. Mann-Whitney rank- sum test was used to compare the data of non-normal distribution between the two groups. Results: (1) Baseline data were compared among 4 subgroups of terlipressin RA-NAKI and control RA-AKI. Control group age was higher than that of terlipressin group, and the serum creatinine (SCr) of the RA-AKI group was higher than RA-NAKI group, and there was no significant difference in the rest of the baseline data and the combined medication (P > 0.05). (2) An intra-group comparison between control and trelipressin before and after treatment showed that all patients had lower body mass, abdominal circumference and deepest ascites, and higher serum albumin (P < 0.05). 24-hour urine volume and MAP was significantly increased in the terlipressin group, while the pre-ascites, SCr and child Turcotte Pugh (CTP) scores were decreased. Body weight, abdominal circumference, pre-ascites, and deepest ascites of the terlipressin group were decreased, while MAP was increased during the treatment and follow-up periods. The differences were statistically significant when compared with the control group at the same time (P < 0.05). There was a statistically significant difference in the increase of 24-h urine volume in the terlipressin group compared with the control group (P < 0.05). The decrease in SCr and CTP in the terlipressin group after 2 weeks of treatment and 4 weeks of follow-up was statistically significant compared with the control group (P < 0.05). (3) Among the two subgroups of RA-AKI and RA-NAKI in the terlipressin group, the baseline SCr value of the former was higher than that of the latter. After treatment, the body weight, abdominal circumference, pre-ascites, deepest ascites and CTP scores were decreased. In the RA-AKI group, 24-hour urine volume, MAP, SCr and serum albumin concentration were significantly increased. The difference between the two subgroups before and after treatment was compared, and the body weight of RA-AKI group at 1, 2 weeks of treatment and 4 weeks of follow-up was significantly lower than RA-NAKI group, which were (- 2.3 ± 0.2 vs. - 1.5 ± 0.2) kg, (- 4.1 ± 0.2 vs. - 2.6 ± 0.2) kg, (- 4.2 ± 0.3 vs. - 2.4 ± 0.3) kg, respectively. RA-NAKI group urine volume was significantly increased at 2 weeks of treatment and 4 weeks of follow-up, which was (468 ± 42 vs. 110 ± 131) ml, (272 ± 34 ml vs. 11 ± 112) ml, respectively. SCr reduction (18.3 ± 4.7 vs. 0.9 ± 2.4) µmol/l at 4 weeks of follow-up was apparent in RA-NAKI group, and the difference was statistically significant (P < 0.05). Conclusion: Addition of terlipressin to conventional treatment may significantly increase MAP, 24-h urine volume, improve renal function and promote ascites resolution in patients with refractory cirrhotic ascites. Moreover, its combination effect is more obvious in AKI patients, and adverse reactions are mild.

[Construction and preliminary study on biological characteristics of composite cell sheets of mesenchymal stem cells and endothelial progenitor cells derived from peripheral blood]

Objective

To separate peripheral blood mesenchymal stem cells (PBMSC) and peripheral blood endothelial progenitor cells (PBEPC) from peripheral blood, and investigate the biological characteristics of composite cell sheets of PBMSC and PBEPC.

Methods

The peripheral blood of healthy adult New Zealand white rabbits was extracted and PBMSC and PBEPC were separated by density gradient centrifugation. Morphological observation and identification of PBMSC and PBEPC were performed. The 3rd generation of PBMSC and PBEPC were used to construct a composite cell sheet at a ratio of 1∶1, and the 3rd generation of PBMSC was used to construct a single cell sheet as control. The distributions of cells in two kinds of cell sheets were observed by HE staining. In addition, the expression of alkaline phosphatase (ALP), osteocalcin (OCN), and vascular endothelial growth factor (VEGF) in the supernatants of cell sheets were observed by ELISA at 1, 5, and 10 days after osteogenic induction.

Results

The morphology of PBMSC was spindle-shaped or polygonal, and PBMSC had good abilities of osteogenic and adipogenic differentiation. The morphology of PBEPC was paved stone-like, and the tube-forming test of PBEPC was positive. Two kinds of cell sheets were white translucent. The results of HE staining showed that the composite cell sheet had more cell layers and higher cell density than the single cell sheet. The expressions of ALP, OCN, and VEGF in the supernatant of the two groups of cell sheets increased with the time of induction. The expression of OCN in the group of composite cell sheet was significantly higher than that in the group of single cell sheet on the 5th and 10th day, ALP on the 10th day was significantly higher than that in the group of single cell sheet, VEGF expression on the 1st, 5th, and 10th day was significantly higher than that in the group of single cell sheet, all showing significant differences ( P<0.05), and there was no significant difference between the two groups at other time points ( P>0.05).

Conclusion

PBMSC have stable differentiation ability, and they have good application prospects because of their minimally invasive access. Composite cell membranes constructed by co-culture of two kinds of cells and induction of membrane formation provides a new idea and exploration for tissue defect repair.

Baicalin Inhibits Coxsackievirus B3 Replication by Reducing Cellular Lipid Synthesis

Baicalin is a flavonoid extracted from Scutellariae Radix and shows a variety of biological activities as reducing lipids, diminishing inflammation, and inhibiting bacterial infection. However, there is no report of baicalin against CVB3 infection. In this study, we found that baicalin can reduce viral titer in a dose-dependent manner in vitro at a dose with no direct virucidal effect. Moreover, we revealed that baicalin can also improve survival rate, reduce heart weight/body weight ratio, prevent virus replication, and relieve myocardial inflammation in the acute viral myocarditis mouse model induced by CVB3. Then, in order to explore the mechanism of baicalin inhibiting CVB3 replication, we respectively examined the expression of autophagosome marker LC3-II by Western blot, tested the concentration of free fatty acid (FFA) and cholesterol (CHO) by commercial kits, detected the mRNA levels of fatty acid synthase (Fasn) and acetyl coenzyme a carboxylase (ACC) by RT-PCR, and observed the lipid content of cells by fluorescence staining. The results showed that CVB3 infection increased autophagosome formation and lipid content in HeLa cells, but these changes were significantly blocked by baicalin. Finally, in order to confirm that baicalin inhibits viral replication and reduces autophagosome formation by reducing cellular lipids, we added exogenous palmitate to cell culture supernatants to promote intracellular lipid synthesis and found that palmitate did not alter LC3-II and CVB3/VP1 expression in HeLa cells with or without CVB3 infection. Interestingly, palmitate can reverse the inhibitory effect of baicalin on autophagosome formation and viral replication. In conclusion, our results indicated that lipids play an important role in CVB3 replication, and the effect of baicalin against CVB3 was associated with its ability to reduce cellular lipid synthesis to limit autophagosome formation.

Observation of spin-glass like behavior in the layered oxyselenides La2O3(Mn1−xCox)2Se2

We have synthesized a new series of layered oxyselenides La₂O₃(Mn_1−xCo_x)₂Se₂ through a solid state reaction method.

Regulation and Directing Stem Cell Fate by Tissue Engineering Functional Microenvironments: Scaffold Physical and Chemical Cues

It is well known that stem cells reside within tissue engineering functional microenvironments that physically localize them and direct their stem cell fate. Recent efforts in the development of more complex and engineered scaffold technologies, together with new understanding of stem cell behavior in vitro, have provided a new impetus to study regulation and directing stem cell fate. A variety of tissue engineering technologies have been developed to regulate the fate of stem cells. Traditional methods to change the fate of stem cells are adding growth factors or some signaling pathways. In recent years, many studies have revealed that the geometrical microenvironment played an essential role in regulating the fate of stem cells, and the physical factors of scaffolds including mechanical properties, pore sizes, porosity, surface stiffness, three-dimensional structures, and mechanical stimulation may affect the fate of stem cells. Chemical factors such as cell-adhesive ligands and exogenous growth factors would also regulate the fate of stem cells. Understanding how these physical and chemical cues affect the fate of stem cells is essential for building more complex and controlled scaffolds for directing stem cell fate.

Protective Effects of Fucoidan against Hydrogen Peroxide-Induced Oxidative Damage in Porcine Intestinal Epithelial Cells

Simple Summary

High levels of production in intensive farming systems make domestic animals like piglets particularly susceptible to oxidative stress, which is detrimental to intestinal homeostasis and function. It is of paramount importance to identify effective and reliable nutrients to counteract oxidative damage to the porcine intestinal epithelium, especially with the recent phasing out of the use of antibiotics in China. This study indicates that fucoidan could ameliorate hydrogen peroxide-induced oxidative stress in porcine intestinal epithelial cells, primarily owing to the action of fucoidan to facilitate nuclear factor-erythroid 2-related factor-2 signals and cellular antioxidant responses. These findings may provide useful implications for practical swine production.

Abstract

This study was conducted to evaluate the effectiveness of fucoidan in ameliorating hydrogen peroxide (H₂O₂)-induced oxidative stress to porcine intestinal epithelial cell line (IPEC-1). The cell viability test was initially performed to screen out appropriate concentrations of H₂O₂ and fucoidan. After that, cells were exposed to H₂O₂ in the presence or absence of pre-incubation with fucoidan. Hydrogen peroxide increased the apoptotic and necrotic rate, boosted reactive oxygen species (ROS) generation, and disturbed the transcriptional expression of genes associated with antioxidant defense and apoptosis in IPEC-1 cells. Pre-incubation with fucoidan inhibited the increases in necrosis and ROS accumulation induced by H₂O₂. Consistently, in the H₂O₂-treated IPEC-1 cells, fucoidan normalized the content of reduced glutathione as well as the mRNA abundance of NAD(P)H quinone dehydrogenase 1 and superoxide dismutase 1 while it prevented the overproduction of malondialdehyde. Moreover, H₂O₂ stimulated the translocation of nuclear factor-erythroid 2-related factor-2 to the nucleus of IPEC-1 cells, but this increase was further promoted by fucoidan pre-treatment. The results suggest that fucoidan is effective in protecting IPEC-1 cells against oxidative damage induced by H₂O₂, which may help in developing appropriate strategies for maintaining the intestinal health of young piglets.

Surface mineralized biphasic calcium phosphate ceramics loaded with urine-derived stem cells are effective in bone regeneration

BACKGROUND

Segmental bone defects caused by trauma, tumors, or infection are a serious challenge for orthopedists in the world. Recent developments in tissue engineering have provided a new treatment for segmental bone defects. Urine-derived stem cells (USCs) can be obtained noninvasively and might be a new kind of seed cells used in bone tissue regeneration. Therefore, the first aim of the present study was to investigate the biological characteristics of USCs. The second aim of the present study was to study the osteogenic effect of surface mineralized biphasic calcium phosphate ceramics (BCPs) loaded with USCs in vitro and in vivo.

METHODS

We isolated USCs from the urine of healthy adult donors and evaluated the biological characteristics of USCs in vitro. We mineralized the surface of BCPs by simulated body fluid (SBF). Cell adhesion and proliferation of USCs on the surface mineralized BCPs were evaluated. Osteogenic proteins and genes of USCs on the surface mineralized BCPs were texted by enzyme-linked immunosorbent assay (ELISA) and real-time polymerase chain reaction (RT-PCR) assay. Critical-sized segmental bone defects model in New Zealand white rabbits were established and randomly divided into 4 groups (surface mineralized BCPs loaded with USCs, BCPs loaded with USCs, surface mineralized BCPs, and BCPs) based on the implant they received. The therapeutic efficacy of the scaffolds in a large bone defect at post-implantation was evaluated by imaging and histological examination.

RESULTS

USCs isolated in our study expressed stem cell-specific phenotypes and had a stable proliferative capacity and multipotential differentiation capability. Surface mineralized BCPs promoted osteogenic proteins and genes expression of USCs without affecting the proliferation of USCs. After 10 weeks, the amount of new bone formation was the highest in the group of surface mineralized BCPs loaded with USCs.

CONCLUSION

USCs, from non-invasive sources, have good application prospects in the field of bone tissue engineering. Surface mineralized BCPs can significantly enhance osteogenic potential of USCs without changing biological characteristics of BCPs. Surface mineralized BCPs loaded with USCs are effective in repairing of critical-sized segmental bone defects in rabbits.

Ferromagnetic insulator Cr2Ge2Te6 as a modulator for generating near-infrared bright-dark soliton pairs

Novel two-dimensional (2D)-materials-based ultra-fast modulators exhibit significance in extending the fundamental investigations and practical applications of mode-locked fiber lasers. In our work, employing the liquid-phase exfoliation method, a ${{\rm Cr}_2}{{\rm Ge}_2}{{\rm Te}_6}$Cr₂Ge₂Te₆ (CGT) optical modulator with a modulation depth and a saturable intensity of 1.64% and ${6.31}\,\,{{\rm MW/cm}^2}$6.31MW/cm² was fabricated. Due to its suitable modulation properties and high nonlinear coefficient, a stable bright-dark soliton pair was successfully achieved within an Er-doped fiber laser. Under the pump power of 560 mW, the maximum average output power was 5.36 mW with a pulse repetition rate of 1.835 MHz. Our results fully present the capacity of CGT in designing bright-dark soliton operations and provide a meaningful reference for promoting the ultra-fast modulation applications of ferromagnetic insulators.

A quantitative evaluation method for wastewater toxicity based on a microbial fuel cell

A microbial fuel cell (MFC) was successfully developed as a toxicity biomonitoring system to enable a quick response to wastewater with unknown toxicity in toxic events. The objective was to quantitatively assess the toxicity of wastewater by a rapid method. Different concentrations of formaldehyde were introduced into the anode chamber, which led to different stages of voltage change. A relationship between the linear slope of the voltage drop stage and the formaldehyde concentration was established through dose-response fitting results. This relationship makes it possible to convert an unknown toxicity of wastewater into the equivalent concentration of formaldehyde. The minimum detection limit in this study was 13 mg/L formaldehyde equivalents. As the toxicity of the wastewater increased, the test time could be reduced to as low as 921 s or even shorter, with a detection error of 3-12 mg/L. By using this evaluation method, oxidized tail gas scrubber wastewater was identified as the main toxic wastewater component in a phenol acetone production plant.

Clinical Evidence for Treatment of Distal Tibiofibular Syndesmosis Injury: A Systematic Review of Clinical Studies

No consensus had been reached about the optimal treatment for syndesmotic fixation. We performed a review of randomized controlled trials (RCTs) to assist in clarifying many of the controversies that were debated for years despite new technology and options. PubMed, Embase, and the Cochrane Library were searched through specific terms and limits. Only RCTs were selected for final inclusion. Study screening and data extraction were performed independently by 2 reviewers. Thirteen RCTs, including 828 cases, met the inclusion criteria and are summarized in this review. Pooled results demonstrated that dynamic fixation had better functional outcomes as well as lower rates of malreduction and complications compared with syndesmotic screw fixation. Both absorbable screw and tricortical screw fixation showed similar results to quadricortical metallic screws. Therefore, dynamic fixation is recommended for the treatment of syndesmosis injuries.

The introduction of benzimidazole and ether moieties into poly(p-phenylene terephthalamide): effects on its microstructure, interactions and properties

Co-poly(p-phenylene terephthalamide) (co-PPTA) fibers containing 4,4′-oxidianiline (4,4′-ODA) and 2-(4-aminophenyl)-5-aminobenzimidazole (BIA) in terephthaloyl chloride (TPC) and p-phenylene diamine (p-PDA) were prepared via a wet spinning method, followed by water washing and drawing at a high temperature. With the addition of a new acid-binding agent, imidazole, the solution prepared by low-temperature polycondensation had suitable viscosity for spinning. Herein, the properties of six co-PPTA fibers with different contents of BIA and 4,4′-ODA segments were studied. The mechanical properties of the co-PPTA fibers were improved with the addition of BIA and ODA; they reached the optimum tensile strength of 2.45 GPa at a p-PDA/ODA/BIA molar ratio of 2/4/4, which showed a higher degree of orientation and the highest crystallinity, and the strength further increased on increasing the thermal drawing ratio. X-ray diffraction indicated that the fibers exhibited highly ordered structures, while two-dimensional wide angle X-ray diffraction showed that molecular packing regions with highly oriented structures were formed. In addition, the co-PPTA fibers exhibited excellent thermal stability when the 5% weight loss temperature was above 492 °C under nitrogen, and glass transition occurred at about 290 °C.

Co-poly(p-phenylene terephthalamide) fibers containing 4,4′-oxidianiline and 2-(4-aminophenyl)-5-aminobenzimidazole in terephthaloyl chloride and p-phenylene diamine were prepared via a wet spinning method, followed by water washing and drawing at high temperature.

Broadband nonlinear absorption properties of two-dimensional hexagonal tellurene nanosheets

Two dimensional (2D) Group-VI Te, tellurene, was successfully exfoliated using a liquid phase exfoliation (LPE) method. The prepared tellurene nanosheets possessed a thickness of 4.3-4.6 nm and the lateral dimension ranged from hundreds of nanometers to several microns. The broadband nonlinear absorption properties were explored for the first time (as we know) using a z-scan method with the laser photon energy in the range of 0.73-2.76 eV, corresponding to the near-infrared-visible waveband. Tellurene nanosheets exhibited excellent broadband saturated absorption and optical limiting behaviors. The low saturable intensity and the large modulation depth for saturated absorption with low energy photon excitation highlight the superiority of the infrared band as a saturable absorber. In addition, with large energy excitation, tellurene manifested an apparent two photon absorption behavior in the visible band, thus it can be used as an optical limiting material. By adopting the mode-locking technique, this high-quality saturable absorber can be applied in all-solid-state or fiber lasers to generate ultra-short and ultra-high peak power laser pulses. Meanwhile, tellurene as an optical limiting material can protect the sensitive optical devices and human eyes. So, our work not only demonstrates that tellurene is a promising broadband nonlinear optical material, but also implies its application prospects in optics.