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Soil aggregate is important to soil quality. Straw return is beneficial for soil amendment, but the effects of straw and straw-derived biochar on aggregate formation and stability in paddy soil are unclear. This study carried out a field experiment for 2 years in Northeast China with four treatments: conventional fertilization (CF), straw (ST, 7.5 t ha−1 year−1), biochar (BC, 2.5 t ha−1 year−1), and biochar-based fertilizer (BCF, 0.75 t ha−1 year−1). Compared with the CF and BCF, BC and ST improved the macroaggregates and significantly increased soil total carbon and aggregate organic carbon, indicating a sustained positive role in promoting the formation and stability of aggregates. BC significantly improved aggregate stability. Correlation analysis showed that macroaggregates (2–0.25 mm) can be increased by increasing the heavy fraction organic carbon (HFOC), BC and ST significantly increased the HFOC, and BC had a greater effect. Scanning electron microscopy (SEM) showed that the combination of biochar and soil particles can be captured with strong water scouring. BCF showed an increasing trend in the formation and stability of soil aggregates. In comparison, biochar had a greater effect on promoting the formation of macroaggregates and the stability of soil aggregates with a significant sustainable effect. [ABSTRACT FROM AUTHOR]

In seismically active regions, high-filled embankment slopes on liquefiable soils tend to damage after strong earthquakes. Therefore, post-seismic damages should be estimated as soon as possible to mitigate potential losses. Fragility function is an efficient tool for assessing the seismic vulnerability conditions of structures, which links the probability of exceeding different limit states to seismic intensity. An embankment slope on liquefiable soils at Yading Airport in China was selected as the study object, and a series of numerical analyses of the embankment-foundation system utilizing the finite element method were conducted. Advanced dynamic constitutive models considering liquefaction and hysteresis characteristics were also adopted to simulate the nonlinear stress–strain behavior of soils under cyclic loadings. The post-seismic stability of embankment slopes was assessed using the strength reduction method (SRM) based on the stress–strain analysis. On this basis, the permanent ground deformation (PGD) at the ground-free field conditions was selected as the intensity measure (IM), while the factor of safety (FoS) of the slopes was selected as the damage measure (DM). Then, a procedure was presented for deriving seismic fragility functions with different damage states in light of incremental dynamic analysis (IDA). This paper aims to investigate the effects of different embankment typologies, such as the thickness of liquefiable soils and slope inclination, on the post-seismic vulnerability of embankment slopes. The fragility curves constructed in this study may soon be helpful for predicting the post-seismic damage of similar high-filled embankment slopes on liquefiable soils, which enables efficient traffic control and rapid disaster response. [ABSTRACT FROM AUTHOR]

In this paper, the extension method is applied to the assessment of seismic damage risk in mountain tunnels. Based on various considerations such as the geological conditions of the tunnel site, the state of the tunnel, the structural situation and the earthquake, the seismic damage risk assessment index for mountainous tunnels is proposed. The range of values of different assessment indexes under each grade is quantified. The seismic damage risk of the tunnel is divided into four classes, and assessed based on the extension theory. The specific assessment process is as follows: Firstly, five tunnels affected by the Wenchuan earthquake were selected to construct the matter element to be assessed, and construct the classical domain and nodal domain; then, the entropy weight method and analytical hierarchy process (AHP) were used to determine the weights of each index; finally, the correlation function values were calculated to obtain the seismic damage risk level of the tunnels. Among them, the seismic damage risk level of the Longchi tunnel and Longxi tunnel is "high risk", and the seismic damage risk level of the Longdongzi tunnel, Youyi tunnel and Maanshi tunnel is "moderate risk". The five tunnels are sorted according to the eigenvalues of the seismic damage risk level as follows: Longchi tunnel > Longxi tunnel > Longdongzi tunnel > Youyi tunnel > Maanshi tunnel. Combined with the seismic damage investigation of the Wenchuan earthquake, the actual seismic damage of tunnel is consistent with the assessment results, which verifies the accuracy and effectiveness of this method. The seismic damage risk assessment model for mountain tunnels proposed in this paper has certain reference value for the future seismic damage risk assessment of tunnels. [ABSTRACT FROM AUTHOR]

Continuous cropping obstacles limit soybean production. Biochar is beneficial for soybean growth, but it is unclear whether biochar performs a sustainable role in continuous cropping. To further explore the effects of biochar on soil properties and soybean growth, a ceramic Wagner pot-simulated field experiment was conducted with biochar at different doses (12, 24, and 48 t·ha−1) over a period of 3 years, no fertilizer, no biochar (CK) and fertilizer (F)treatments were used for comparison. The results showed that biochar significantly reduced soil bulk and improved the rhizosphere soil pH, available nutrients (N, K), and total nutrients (C, N, P, and K) compared with CK and F. Moreover, the soybean root length, surface area, volume, and exudates increased with biochar amendment. In particular, biochar significantly increased the nodule number, dry weight, and nitrogenase activity of soybean. Furthermore, biochar promoted soybean growth and increased soybean yield. In general, we found that the soybean yield increased with biochar and that biochar had a positive, sustainable effect on soil properties and soybean root growth, providing a new cultivation measure for soil health and soybean production in continuous cropping, which is very important for increasing soybean productivity to break the limitations of soybean traditional continuous cultivation. [ABSTRACT FROM AUTHOR]

The objective is to clarify the effects of Notch/p38MAPK signaling pathway on articular cartilage defect recovery by BMSCs tissue and provide a basis for clinical treatments of articular cartilage defects. A total of 96 healthy male rabbits (weighed 1.5–2.0 kg) that were fully-grown were selected and grouped as the no-treatment group, the model group, and the treatment group in a random manner. Each group included 32 rabbits in total. The no-treatment group was fed without any interventions. The model group and the treatment group were constructed into rabbit knee-joint articular cartilage defect models. In addition, rabbits in the treatment group were given intervention treatments with Notch inhibitor (DAPT) combined with p38MAPK inhibitor (SB203580). The general conditions of rabbits in each group and the conditions of the stained articular cartilage tissue samples were observed, the proliferation of chondrocytes of rabbits in each group was compared. (1) After drug interventions, in contrast to the rabbits in the model group, the general conditions and the chondrocyte recovering situations of rabbits in the treatment group were obviously improved; (2) 8 weeks after model construction, the articular cartilage empty bone lacuna rate of rabbits in the treatment group was (12.13 ± 1.81)%, which was obviously lower than the synchronous (21.55 ± 3.07)% articular cartilage empty bone lacuna rate of rabbits in the model group, and there was a statistical significance in the differences (P < 0.05); (3) the absorbance value (OD value) of chondrocytes in the treatment group was (0.34 ± 0.015), which was obviously higher than the (0.10 ± 0.020) OD value of chondrocytes in the model group, and there was a statistical significance in the differences (P < 0.05). The inhibition of Notch/p38MAPK signaling pathway can promote the recovery of articular cartilage by BMSCs tissue, accelerate the proliferation of chondrocytes, and contribute to the recovery of knee-joint injuries in rabbits, which provides a reliable basis for clinical treatments of articular cartilage defects. [ABSTRACT FROM AUTHOR]

There has been no consensus on the treatment or prognosis of Hepple stage V osteochondral lesions of the talus (OLTs), especially for lesions greater than 1.5 cm2 in size. The objective of this study was to investigate the clinical outcomes achieved upon application of a platelet-rich plasma (PRP) scaffold with a cancellous bone autograft for Hepple stage V OLTs. Fourteen patients (mean age, 39 years) were treated with a cancellous bone graft and a PRP scaffold between 2013 and 2015. The mean time to surgical treatment was 23.5 months. Ankle X-ray and magnetic resonance imaging were performed at the final follow-up. Functional outcomes were evaluated according to the Visual Analog Scale (VAS) score, American Orthopaedic Foot and Ankle Society (AOFAS) score, and Short Form 36 (SF-36) score. The range of motion (ROM) of the ankle joint and complications also were recorded. Thirteen patients completed the full follow-up, with a mean follow-up duration of 18 months. MRI demonstrated the complete regeneration of subchondral bone and cartilage in all patients. The postoperative VAS, AOFAS ankle and hindfoot, and SF-36 scores were improved significantly (all P<0.001) without obvious complications. We suggest that, for the Hepple stage V OLTs, management with cancellous bone graft and PRP scaffold may be a safe and effective treatment. [ABSTRACT FROM AUTHOR]

Background: Photosynthesis is the key to crop yield. The effect of biochar on photosynthetic physiology and soybean yield under continuous cropping is unclear. We conducted a long-term field experiment to investigate the effects of co-application of biochar and fertilizer (BCAF) on these parameters. Five treatments were established: F2 (fertilizer), B1F1 (3 t hm -2 biochar plus fertilizer), B1F2 (3 t hm -2 biochar plus reduced fertilizer), B2F1 (6 t hm -2 biochar plus fertilizer), and B2F2 (6 t hm -2 biochar plus reduced fertilizer)., Results: BCAF increased chlorophyll and leaf area, enhancing soybean photosynthesis. The net photosynthetic rate (P n ), transpiration rate (T r ), stomatal conductance (G s ), water use efficiency (WUE) and intercellular carbon dioxide (CO 2 ) concentration (C i ) were enhanced by BCAF. In addition, BCAF improved soybean photosystem II (PSII) photosynthetic performance, driving force, potential photochemical efficiency (F v /F 0 ), and quantum yield of electron transfer (φ E0 ). Furthermore, BCAF enhanced the accumulation of photosynthetic products, such as soluble proteins, soluble sugars and sucrose content, resulting in higher leaf dry weight. Consequently, BCAF increased the soybean yield, with the highest increase of 41.54% in B2F1. The correlation analysis revealed positive relationships between soybean yield and chlorophyll, leaf area, maximal quantum yield of PSII (F v /F m ), electron transport flux per cross-section at t = 0 (ET 0 /CS 0 ), trapped energy flux per cross-section at t = 0 (TR 0 /CS 0 ), composite blade driving force (DF Total ), and leaf dry weight., Conclusions: We demonstrated that long-term BCAF enhances soybean photosynthesis under continuous planting, reduces fertilizer use and increases yield. This study reveals a novel way and theory to sustainably increase soybean productivity. © 2023 Society of Chemical Industry., (© 2023 Society of Chemical Industry.)

Objectives: With positive outcomes recorded, the mixed reality (MR) technology has lately become popular in orthopedic surgery. However, there are few studies that specifically address the utility of MR in talocalcaneal coalitions (TCC) resection. Our goal in this retrospective study is to assess certain data while examining the viability of using MR to treat TCC resection., Methods: Six consecutive patients with TCC diagnosed by computed tomography (CT) for which nonoperative therapy had failed and MR system assisted TCC resection were included in this study from March 2021 to December 2021. The feasibility and accuracy of TCC resection were assessed by post-operation radiography. The American Orthopaedic Foot & Ankle Society (AOFAS) hindfoot score and visual analog scale (VAS) score were used to assess the recovery condition and pain level pre- and post-operation., Results: The surgeon can accurately resect the TCC according to the preoperatively determined range by superimposing the holographic model with the actual anatomy of the TCC using an MR system. Additionally, no additional x-ray was necessary while operating. Mean follow-up was 10.3 months, with a minimum of 6 months. There is a significant difference between the preoperative AOFAS score of 53.4 ± 3.8 and the 6-month follow-up AOFAS score of 97.3 ± 2.2 ( p  < 0.05). There is also a significant difference between the preoperative VAS score of 8.1 ± 0.7 and the 6-month follow-up VAS score of 1.7 ± 0.4 ( p  < 0.05). All individuals had clinical subtalar mobility without stiffness following surgery., Conclusion: While the TCC resection operation is being performed, the application of MR technology is practicable, effective, and radiation-free, giving surgeons satisfactory support., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Zhang, Wang, Li, Fu, Gu and Shi.)

Objective: The study aims to investigate the functional outcome of the lateral approach for insertional Achilles tendinitis (IAT) with Haglund deformity., Methods: From January 2016 to September 2019, 14 cases of IAT with Haglund deformity that resisted conservative treatment received surgery in our department. A lateral approach was used to debride the bony and soft tissue and reattach the insertion of the Achilles tendon. The Visual Analog Scale (VAS), American Orthopedic Foot and Ankle Score (AOFAS), and Victorian Institute of Sport Tendon Study Group-Achilles Tendinopathy score (VISA-A) were used to evaluate clinical outcomes., Result: The mean patient age was 39.57 years at the time of surgery. The mean follow-up was 14.74 months. The mean VAS score significantly decreased from 4.86 ± 0.86 preoperatively to 1.21 ± 1.58 postoperatively ( P  < 0.001). The mean AOFAS score significantly improved from 66.64 ± 6.23 preoperatively to 90.21 ± 11.50 postoperatively ( P  < 0.001). The mean preoperative and the last follow-up VISA-A were 66 (range 56.75-69.25) and 86 (range 75.75-97.00) points, respectively ( P  < 0.05)., Conclusion: The lateral approach was effective and safe for IAT with Haglund deformity. Moreover, the mid-term functional outcome was promising., Level of Clinical Evidence: IV., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Jiang, Wang, Fu, Wang, Wu, Yao, Song, Gu, Yang, Xue and Shi.)

Background: Because of the rising prevalence of anterior talofibular ligament (ATFL) damage, there is a considerable interest in developing innovative techniques to improve the biological healing response of ATFL. Platelet-rich plasma (PRP) includes several growth factors linked to a favorable healing response, however none of the studies involved both quality evaluation and clinical results to evaluate this treatment. Purpose: To determine the clinical results of PRP injections into the ATFL in lateral ankle sprain (LAS) patients, as well as the quality of the ATFL based on radiographic outcomes. Methods: Patients with clinically confirmed grade II LAS for the first time ( n = 83) were examined. The clinical outcomes of three types of injection methods were evaluated: none, once within 48 h after the sprain, and once more 4 weeks later after first injection. PRP was injected into the tear site of the ATFL using ultrasound guidance, and all ankles were immobilized for 2 weeks. The American Orthopedic Foot and Ankle Score (AOFAS) ankle-hindfoot scale and the Visual Analogue Scale (VAS) were used to assess the results at 2, 6, 8, 24, and 48 weeks of follow-up. The signal/noise ratio (SNR) value of Magnetic Resonance Imaging (MRI)-based ATFL signal intensity can disclose ATFL quality. The ATFL SNR results were then assessed 8, 24 and 48 weeks following the first injection to compare ATFL quality. Results: The PRP injection groups outperformed the control group in terms of clinical outcomes, and the two injections group outperformed other groups in terms of pain reduction and functional outcome at 8 weeks. The clinical results of all groups were comparable at 6 and 12 months follow-up. ATFL SNR findings improved significantly across all groups over time. At the same follow-up time, the PRP injection groups outperformed the control group, and the best SNR result showed in the two injections group at the final follow-up. Conclusion: PRP injection helped relieve early symptoms of LAS, although all patients saw a similar development after 6 months. The two PRP injections group produced considerably better clinical results and quality of the ATFL in short-term follow-up., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zhang, Wang, Li, Fu, Gu and Shi.)

This study was conducted to investigate the effects of high-altitude hypoxic environments on the gut microbiota. Male Sprague-Dawley rats were randomly divided into three groups, namely, the plain, moderate-altitude hypoxic, and high-altitude hypoxic groups. On the 3rd, 7th, 15th, and 30th days of exposure, fecal samples were collected and analyzed via 16S rRNA gene sequencing technology. Fecal microbiota transplantation (FMT) experiments were also performed. The results showed significant differences between the gut microbiota structure and diversity of rats in the high-altitude hypoxic group and those of rats in the other groups. Further, compared with that of rats in the plain group, the gut microbiota of rats in the two hypoxic groups showed the most significant changes on day 7. Furthermore, the gut microbiota of the rats in the FMT groups exhibited changes and became increasingly similar to those of the rats in the hypoxic groups. We also identified the phylum Firmicutes , genus Akkermansia , and genus Lactobacillus as the core microbiota under hypoxic conditions. Phenotypic analysis indicated a decrease in the proportion of aerobic bacteria and an increase in that of anaerobic bacteria, possibly owing to the high-altitude hypoxic environment. Additionally, functional analysis showed significant differences between the different groups with respect to different metabolic pathways, including carbohydrate metabolism, energy metabolism, glycan biosynthesis, and metabolism. These findings indicated significant changes in gut microbiota structure and diversity under high-altitude hypoxia, establishing a foundation for further research on the pathogenesis and development of diseases, as well as drug metabolism, under high-altitude hypoxia. IMPORTANCE In this study, we investigated the effects of high-altitude hypoxic environments with low oxygen levels on the gut microbiota characteristics of rats. We observed that high-altitude hypoxia is an important environmental factor that can affect gut microbiota structure and diversity, thereby affecting homeostasis in the host intestinal environment. These findings provide a basis for further studies on disease initiation and development, as well as drug metabolism, in high-altitude hypoxic environments.

Hypoxia, an essential feature of high-altitude environments, has a significant effect on drug metabolism. The hypoxia-gut microbiota-CYP450/drug transporter axis is emerging as a vital factor in drug metabolism. However, the mechanisms through which the gut microbiota mediates the regulation of CYP450/drug transporters under high-altitude hypoxia have not been well defined. In this study, we investigated the mechanisms underlying gut microbial changes in response to hypoxia. We compared 16S ribosomal RNA gene sequences of the gut microbiota from plain and hypoxic rats. As a result, we observed an altered gut microbial diversity and composition in rats under hypoxia. Our findings show that dysregulated gut microbiota changes CYP3A1 and MDR1 expressions in high-altitude hypoxic environments. Thus, our study reveals a novel mechanism underlying the functioning of the hypoxia-gut microbiota-CYP450/drug transporter axis., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Bai, Yang, Liu, Zhu, Wang, Gu, La and Li.)

Hypoxia is the main characteristic of a high-altitude environment, affecting drug metabolism. However, so far, the mechanism of microRNA (miRNA) involved in the regulation of drug metabolism and transporters under high-altitude hypoxia is still unclear. This study aims to investigate the functions and expression levels of multidrug resistance protein 1 (MDR1), multidrug resistance-associated protein 2 (MRP2), breast cancer resistance protein (BCRP), peptide transport 1 (PEPT1), and organic anion-transporting polypeptides 2B1 (OATP2B1) in rats and colon cancer (Caco-2) cells after exposure to high-altitude hypoxia. The protein and mRNA expression of MDR1, MRP2, BCRP, PEPT1, and OATP2B1 were determined by Western blot and qPCR. The functions of MDR1, MRP2, BCRP, PEPT1, and OATP2B1 were evaluated by determining the effective intestinal permeability and absorption rate constants of their specific substrates in rats under high-altitude hypoxia, and uptake and transport studies were performed on Caco-2 cells. To screen the miRNA associated with hypoxia, Caco-2 cells were examined by high throughput sequencing. We observed that the miR-873-5p was significantly decreased under hypoxia and might target MDR1 and pregnane X receptor (PXR). To clarify whether miR-873-5p regulates MDR1 and PXR under hypoxia, Caco-2 cells were transfected with mimics or inhibitors of miR-873-5p and negative control (NC). The function and expression of drug transporters were found to be significantly increased in rats and Caco-2 cells under hypoxia. We found that miR-873-5p regulated MDR1 and PXR expression. Herein, it is shown that miRNA may affect the expression of drug transporter and nuclear receptor under hypoxia. SIGNIFICANCE STATEMENT: This study explores if alterations to the microRNAs (miRNAs), induced by high-altitude hypoxia, can be translated to altered drug transporters. Among miRNAs, which show a significant change in a hypoxic environment, miR-873-5p can act on the multidrug resistance protein 1 (MDR1) gene; however, there are multiple miRNAs that can act on the pregnane X receptor (PXR). This study speculates that the miRNA-PXR-drug transporter axis is important in the physiological disposition of drugs., (Copyright © 2022 by The American Society for Pharmacology and Experimental Therapeutics.)

Background: Hypoxia has a negative effect on the cardiovascular system, nervous system, and metabolism, which contributes to potential changes in drug absorption, distribution, metabolism, and excretion (ADME). However, hypoxia can also alter the expression of microRNA (miRNA), thereby regulating drug-metabolizing enzymes, transporters, and ADME genes, such as hypoxia-inducible factor, inflammatory cytokine, nuclear receptor, etc. Therefore, it is crucial to study the role of miRNA in the regulation of drug-metabolizing enzymes and transporters under hypoxia., Methods: A systematic review of published studies was carried out to investigate the role of miRNA in the regulation of drug-metabolizing enzymes and transporters under hypoxia. Data and information on expression changes in miRNA, drug-metabolizing enzymes, and transporters under hypoxia were analyzed and summarized., Results: Hypoxia can up or down-regulate the expression of miRNA. The effect of hypoxia on Cytochrome P450 (CYP450) is still a subject of debate. The widespread belief is that hypoxia decreased the activity and expression of CYP1A1, CYP1A2, CYP2E1, and CYP3A1 and increased those of CYP3A6 and CYP2D1 in rats. Hypoxia increased the expression of a multidrug resistance-associated protein, breast cancer resistance protein, peptide transporter, organic cation transporter, and organic anion transporter. miRNA negatively regulated the expression of drugmetabolizing enzymes and transporters., Conclusion: The findings of this review indicated that miRNA plays a key role in the expression changes of drugmetabolizing enzymes and transporters under hypoxia., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

There are still controversies on the management and outcome of open Lisfranc injury in available studies. This study evaluates the staged management of Lisfranc injury and its complications.Patients who received a staged strategy for open Lisfranc injury were reviewed.One patient with degloving injury suffered from partial skin and hallux necrosis which was treated by debridement, hallux amputation, definitive internal fixation, and local flap transfer on the 12th day after first stage management. A definitive internal fixation and simultaneous skin graft or flap coverage were performed in another 3 patients with soft tissue defects. Other patients without soft tissue problems underwent a second stage of definitive internal fixation. Bone union was observed on the 12.5th week after definitive surgery. The median AOFAS midfoot score at the last follow-up was 74.4 ± 8.7, while the average VAS score was 2.2 ± 1.8. The average return-to-work time was 8th months postoperatively in 9 patients. Flap necrosis, infection, implant failure, nonunion, and osteomyelitis were not observed during the follow-up. Two patients received Lisfranc arthrodesis for persistent pain due to posttraumatic arthritis.In the management of open Lisfranc injury, surgeons must consider soft tissue condition. Staged strategy is a rational protocol for this severe injury. Temporary K-wire fixation after early radical debridement and realignment will facilitate the definitive internal fixation until soft tissue condition improves, which also can decrease the soft tissue complication.

Objective: To investigate the feasibility and efficacy of repairing osteochondral defects with mosaicplasty and allogeneic bone marrow mesenchymal stem cells (BMSCs) transplantation., Methods: BMSCs were harvested from rabbits and maintained in vitro. Cells of third passage were mixed with pluronic F-127. Osteochondral defect animal model was established in rabbits and then this defect was treated with autologous osteochondral grafts with or without BMSCs above mentioned. In control group, pure pluronic F-127 was filled in the defect. Histological and immunohistological examinations were performed for the evaluation of therapeutic effectiveness., Results: Autologous osteochondral grafts in both groups were not loose, prolapsed and depressed. In BMSCs group, the tissues in the "death space" became hyaline cartilage. The arrangement of chondrocytes was regular. At 4, 8, 12 and 16 weeks, O'Driscoll and Keeley and Salter score were 14.00±1.00, 16.75±1.71, 18.00±0.82 and 20.50±1.29 in BMSCs group, which were significantly higher than those in control group (7.67±0.58, 8.00±0.82, 8.50±0.58 and 9.00±0.82, respectively). There were significant differences among different treatments (F=584.028, P=0.000), but the score was comparable between right defect and left defect (F=0.028, P=0.890). In addition, significant difference was also observed at different time points (F=18.364, P=0.000), but there was no interaction between time and treatment (F=6.939, P=0.015). Moreover, interactions among other factors were also not observed., Conclusion: Mosaicplasty and BMSC transplantation are effective to repair the osteochondral defects and integrate the "death space", achieving a better therapeutic efficacy. Thus, this combined therapy may become an effective strategy for the therapy of osteochondral defects.