Roadway rock burst prediction based on catastrophe theory.

In order to quantitatively calculate the critical depth and critical load of mines affected by rock burst, and to achieve effective prevention and control of rock burst in coal mines, this paper proposes a mechanical model for predicting the occurrence of rock burst in coal mine roadways based on catastrophe theory. Additionally, a theoretical calculation formula for initiating rock burst is derived. The first step was to establish a mechanical analysis model, which directly correlated with the in-situ stress, physical and mechanical characteristics of the coal-rock mass, and engineering structural parameters. Following this, a mechanical instability criterion was derived for the key load-bearing circle within the surrounding rock of the roadway. In the final step, the critical depth and load for rock burst initiation were verified for 25 distinct coal mines in China that were prone to rock burst hazards. The research results demonstrate that the discrepancy between the theoretically calculated critical depth and the actual measured statistical values was less than 35%. In addition, the difference between the theoretically determined critical depth and the value calculated by Pan Yishan was less than 32%. Notably, the ratio of the theoretically calculated critical load to the uniaxial compressive strength of the coal-rock mass ranged from 0.38 to 1.93. This aligns with empirical data on rock burst occurrences, as set out in the engineering classification standards for rock masses. These research outcomes substantiated the practical utility of the proposed theory, thereby laying a robust theoretical groundwork for the quantitative control of rock burst.

Degradation profiles of the poly(ε-caprolactone)/silk fibroin electrospinning membranes and their potential applications in tissue engineering.

Degradation profiles are critical for the optimal application of electrospun polymer nanofibers in tissue regeneration, wound healing, and drug delivery systems. In this study, natural and synthetic polymers and their composites were subjected to in vivo transplantation and in vitro treatment with lipases, macrophages, and acetic acid to evaluate their degradation patterns. The effects of environmental stimulation, surface wettability, and polymer components on the degradation profiles of the electrospinning poly(ε-caprolactone)/silk fibroin (PCL/SF) nanofibers were first evaluated. In vivo degradation study demonstrated that bulk degradation, characterized by the transition from microfibers to nanofibers, and surface erosion, characterized by fusion between the microfibers or direct erosion from both ends of the microfibers, occurred in the electrospun membranes; however, bulk degradation dominated their overall degradation. Furthermore, the degradation rates of the electrospun PCL/SF membranes varied according to the composition, morphology, and surface wettability of the composite membranes. After the incorporation of silk fibroin (SF), the degradation rate of the SF/PCL composite membranes was faster, accompanied by larger values of weight loss and molecular weight (Mw) loss when compared with that of the pure poly(ε-caprolactone) (PCL) membrane, indicating a close relationship between degradation rate and hydrophilicity of the electrospinning membranes. The in vitro experimental results demonstrated that enzymes and oxidation partially resulted in the surface erosion of the PCL/SF microfibers. Consequently, bulk degradation and surface erosion coordinated with each other to enhance the hydrophilicity of the electrospinning membranes and accelerate the in vivo degradation.

Resveratrol-loaded co-axial electrospun poly(ε-caprolactone)/chitosan/polyvinyl alcohol membranes for promotion of cells osteogenesis and bone regeneration.

The guided bone regeneration (GBR) membranes currently used in clinics are usually compromised by their limited osteogenic induction potential. In this study, we fabricate a core-shell poly(ε-caprolactone)/chitosan/polyvinyl alcohol (PCL/CS/PVA) GBR membrane with different amount of resveratrol (RSV), endowing the PCL/CS/PVA GBR membrane with superior osteogenic induction ability, which was not attained by the regular GBR membrane. The prepared GBR membranes were characterized by scanning electron microscopy, transmission electron microscopy, and CCK-8 and live-dead staining assays, and their osteogenic induction ability was evaluated using Col-I immunofluorescence staining, micro-computed tomography, haematoxylin and eosin staining and immunohistochemical staining. Results of the in vitro release experiment confirmed that the membranes exhibited a continuous RSV release profile for 15 days. Furthermore, the cumulative releasing of RSV was increased from 39.68 ± 2.09 µg to 65.8 ± 2.91 µg with increasing contents of RSV from 0.1 % to 0.5 % (w/v) in the core layer of GBR membranes. In particular, the PCL/CS/PVA GBR membrane loading with 0.5 % RSV most efficiently release RSV in a sustained and controlled manner, which significantly induced osteogenic differentiation of pre-osteoblasts in vitro and bone regeneration in vivo. Based on the in vivo histological findings, newly formed bone tissues with 82.46 ± 9.86 % BV/TV and 0.70 ± 0.07gcm-3 BMD were generated in the defect sites treated by the GBR membrane loaded with 0.5 % RSV, which were the largest values among those for all three groups after 12 weeks of post implantation. Overall, the PCL/CS/PVA GBR membrane loaded with 0.5 % RSV has significant potential for bone regeneration.

Application of Nanocellulose-Based Aerogels in Bone Tissue Engineering: Current Trends and Outlooks.

The complex or compromised bone defects caused by osteomyelitis, malignant tumors, metastatic tumors, skeletal abnormalities, and systemic diseases are difficult to be self-repaired, leading to a non-union fracture. With the increasing demands of bone transplantation, more and more attention has been paid to artificial bone substitutes. As biopolymer-based aerogel materials, nanocellulose aerogels have been widely utilized in bone tissue engineering. More importantly, nanocellulose aerogels not only mimic the structure of the extracellular matrix but could also deliver drugs and bioactive molecules to promote tissue healing and growth. Here, we reviewed the most recent literature about nanocellulose-based aerogels, summarized the preparation, modification, composite fabrication, and applications of nanocellulose-based aerogels in bone tissue engineering, as well as giving special focus to the current limitations and future opportunities of nanocellulose aerogels for bone tissue engineering.

Citrus alkaline extracts improve LPS-induced pulmonary fibrosis via epithelial mesenchymal transition signals.

BACKGROUND: Acute respiratory distress syndrome (ARDS) is a serious life threatening clinical critical illness. ARDS-related pulmonary fibrosis is a common complication of ARDS. The occurrence of early pulmonary fibrosis indicates a higher incidence and mortality of multiple organ failure. LPS-induced ARDS-related pulmonary fibrosis model in mice was established in this study. And we have explored the anti-pulmonary fibrosis effects and molecular mechanisms of the Citrus Alkaline Extracts (CAE) in vivo and in vitro. METHODS: Pulmonary fibrosis mouse model and lung epithelial cell injury model were established in this study. H&E, Masson and Sirius Red staining were used to estimate lung tissue damage. Immunohistochemistry and western blotting were used to analyze proteins expression. Protein-protein interaction was observed by Co-Immunoprecipitation. Systemic impact of CAE on signaling pathway was examined by RNA-seq. RESULTS: Through H&E, Masson and Sirius Red staining, it was convincingly indicated that therapeutic administration of CAE alleviated lung injury and fibrosis, while pretreated administration of CAE showed weak improvement. In vitro experiments showed that CAE had dual regulation to E-cadherin and N-cadherin, the important indicators of epithelial-mesenchymal transition (EMT). And it was further demonstrated that CAE reversed TGF-ß1-induced EMT mainly through Wnt/ß-catenin, Stat3/6 and COX2/PGE2 signals. Through RNA-Seq, we discovered important mechanisms by which CAE exerts its therapeutic effect. And network pharmacology analysis demonstrated core potential targets of CAE in EMT. CONCLUSION: Thus, this study provides new therapeutic effects of CAE in anti-fibrosis, and offers potential mechanisms for CAE in LPS-induced pulmonary fibrosis.

Needle Removal in the Deep Maxillofacial Region Assisted by Computerized Navigation Technique and Digital Guiding Plate.

Retention of foreign bodies frequently happened in the region of oral and maxillofacial. In very rare cases, the positions of the foreign objects moved with the movement of muscles in the oral and maxillofacial regions. Precise locations of moving objects and minimally invasive surgeries pose a great challenge to surgeons. The case of a 44-year-old female patient diagnosed with retention of the fractured needle is reported in this study. A digital guide plate was manufactured to locate the precise position of the fractured needle and preoperatively mimic the surgery processes. The computerized navigation system guided us to make an incision and precisely target the fractured needle during the surgery. Combing the technologies of the digital guiding plate and navigation system, removing the moving foreign bodies becomes objective, time-saving, and minimally invasive.

Application of a multimedia-supported manikin system for preclinical dental training.

AIM: In this study, we aimed to describe a multimedia-supported manikin system, compare the new manikin with the traditional manikin and evaluate its effectiveness in preclinical dentistry training. METHODS: A total of 150 students participated in this study. Amongst these students, 71 in the 2015-year group used traditional manikins (Group TM) for preclinical training courses (endodontics training courses and prosthodontics training courses), and 79 in the 2016-year group used manikins with a multimedia system (Group MM). The scores of the training courses between the two groups were compared. A questionnaire survey was used to collect opinions of the students in Group MM on their experience of using the multimedia-supported manikin system in the preclinical training. RESULTS: In the endodontics training courses, the scores of Group MM were higher than those of Group TM, but there was no significant difference (P = 0.379 > .05). However, the scores of prosthodontics training courses in Group MM were significantly higher than those in Group TM (P = 0.018 < .05). The questionnaire results indicated that the students in Group MM were satisfied with the device in usability, clarity, effectiveness and improvement in operation proficiency. CONCLUSIONS: In the groups studied, for preclinical dental training, the multimedia-supported manikin system was a good alternative to traditional manikin in preclinical dentistry training.

Implementation of an interactive virtual microscope laboratory system in teaching oral histopathology.

Laboratory course acts as a key component of histopathology education. Recent trends of incorporating visual and interactive technology in active and inquiry-based learning pedagogical methods have led to significant improvement of histopathology laboratory courses. The present work aimed to describe interactive virtual microscope laboratory system (IVMLS) as a virtual platform for teaching histopathology in order to improve the quality and efficiency of teaching. The system is based on interactive technology and consists of interactive software, slide-reading software, teaching resources and integrated auxiliary equipment. It allows real-time interaction between teachers and students and provides students with a wealth of learning and review materials. In order to evaluate the effectiveness of the system, we conducted a comparative study with the use of light microscope (LM) as a method. Specifically, we compared the results of six assignments and one laboratory final exam between IVMLS group and LM group to analyse the impact of IVMLS on students' academic performance. A questionnaire survey was also conducted to obtain students' attitudes and views on this system. There was no overall difference in assignment performance between IVMLS group and LM group. But laboratory final test grades increased from a mean of 62% (43.8-80.0, 95% CI) before to 83% (71.0-94.2, 95% CI) after implement IVMLS, suggesting highly significant (p < 0.001) improvement on students' histopathology laboratory performance. Feedback of the questionnaire was positive, indicating that students were satisfied with the system, which they believed improved student communication and teacher-student interaction, increased learning resources, increased their focus on learning, and facilitated their independent thinking process. This study proves that IVMLS is an efficient and feasible teaching technology and improves students' academic performance.

Treatment of Sagittal Fracture of the Mandibular Condyle Using Resorbable-Screw Osteosynthesis.

PURPOSE: Screw osteosynthesis is advocated for the treatment of sagittal fracture of mandibular condyle (SFMC). This study aimed to explore the applicability of resorbable-screw osteosynthesis in the treatment of SFMC. METHODS: A retrospective cohort study was performed in patients with SFMC treated with resorbable-screw osteosynthesis (group A) from June 2011 through June 2021. The patients who had undergone titanium-screw osteosynthesis served as the control group (group B). The primary outcome variable was fracture healing, defined as follows: 1) normal mouth opening and restoration of pretrauma occlusion; 2) without complications or discomfort of temporomandibular joint symptoms; and 3) fracture union without abnormal reactions or bone resorption in computed tomography images. The secondary outcome variable was condylar morphological changes including radiographic imaging appearance of the condyle, mandibular ramus height (MRH), anteroposterior diameter (APD), and mediolateral diameter (MLD) of the condyle, which were assessed by comparing the computed tomography images 1 week after surgery with those of 3 months after surgery. The collected data of the outcome variables of the 2 groups were analyzed correspondingly using Student's paired t test and Student's t test. RESULTS: There were 24 patients in group A and 71 patients in group B. All the patients displayed an evident improvement in mouth opening and restored pretrauma occlusion. Few patients had complications (group A, 8.33%; group B, 9.86%) and discomfort of temporomandibular joint symptoms (group A, 16.67%; group B, 15.49%). Fracture union without abnormal reactions or bone resorption was observed during the follow-up. The radiographic evaluation revealed no significant difference in the MRH, the maximum APD, and MLD of the condyles between 1 week and 3 months after surgery in both groups. There were no significant intergroup differences in the changes in the MRH, APD, and MLD of the condyles. CONCLUSIONS: Resorbable-screw osteosynthesis is a viable option for the treatment of SFMC.

Classification system of sacroiliac joint dislocation with ipsilateral sacral wing fracture and its validity examination and clinical application evaluation / 中华创伤杂志

Objective:To establish the classification system of sacroiliac joint dislocation with ipsilateral sacral wing fracture (SJDISWF), examine its reliability and evaluate the clinical application.Methods:A multi-center retrospective case series study was conducted to analyze the clinical data of 20 SJDISWF patients admitted to Third Affiliated Hospital of Southern Medical University, Honghui Hospital Affiliated to Xi′an Jiaotong University and Third Hospital of Hebei Medical University from January 2016 to December 2019. There were 8 males and 12 females, aged from 13-58 years［(34.7±13.2)years］. Based on the direction of sacral displacement, SJDISWF was divided into 3 types. Type I: the sacroiliac joint dislocated and the ipsilateral sacral wing fracture fragment was anteriorly prolapsed; Type II: the sacroiliac joint dislocated, the ipsilateral sacral wing fracture fragment was compressed or crushed, the anterior sacral foramen may fractured; Type III: the sacroiliac joint dislocated and the ipsilateral sacral wing fracture end was inserted into the sacral canal, causing an intra-sacral canal occupation. The reliability of the classification was performed based on the assessment results of two phases in four observers at 4-week intervals. Treatments were utilized based on the types I, II, III fractures, including anterior approach for open reduction and internal fixation, closed reduction and internal fixation or posterior approach for open reduction and internal fixation respectively. Postoperative fracture healing time was recorded. Quality of fracture reduction was graded according to Matta′s criteria. Majeed functional score was recorded at postoperative 3 months, 6 months and the final follow-up. Complications were detected as well.Results:The overall Kappa value of inter-observer reliability was 0.890. The overall Kappa value of intra-observer reliability was 0.854. There were 12 patients with type I, 7 with type II and 1 with type III. All patients went through the procedure uneventfully and were followed up for 6-36 months［(20.0±8.7)months］. All patients achieved clinical healing in 8-14 weeks［(10.2±1.7)weeks］. According to the Matta′s criteria for fracture reduction, the outcome was excellent or good in 83% (10/12) for type I, 71% (5/7) for type II and 0% (0/1) for type III, with the overall excellent rate of 75%. Majeed functional score was (74.6±5.2)points at postoperative 3 months and (84.4±5.8)points at postoperative 6 months ( P<0.01). According to Majeed functional score, the outcome was excellent or good in 75% (9/12) for type I, 100% (7/7) for type II and 0% (0/1) for type III at the final follow-up, with the overall excellent rate of 80%. There were no complications such as lateral femoral cutaneous nerve or sciatic nerve injury, lower extremity deep vein thrombosis, sacroiliac joint pain, failure of internal fixation or loss of fracture reduction during the follow-up. Conclusions:The SJDISWF classification has high reliability. The classification-oriented treatment strategy has achieved a relatively satisfactory restoration and functional recovery, indicating that the classification plays a certain role in guiding treatment selection for SJDISWF.

Effect comparison of lateral-rectus approach and ilioinguinal approach in the treatment of toddlers with Torode-Zieg type IV pelvic fracture / 中华创伤杂志

Objective:To compare the clinical efficacy of lateral-rectus approach and ilioinguinal approach in the treatment of Torode-Zieg type IV pelvic fracture in toddlers.Methods:A retrospective cohort study was used to analyze the clinical data of 12 toddlers with Torode-Zieg type IV pelvic fracture admitted to Affiliated Hospital of Youjiang Medical College for Nationalities and Third Affiliated Hospital of Southern Medical University from June 2012 to June 2019. There were 6 males and 6 females, aged 13-36 months [(23.9±7.4)months]. Treatment via ilioinguinal approach was performed for 5 patients (ilioinguinal group), and via lateral-rectus approach for 7 patients (lateral-rectus group). Operation duration, intraoperative blood loss and postoperative complications were compared between the two groups. At the last follow-up, pelvic function was evaluated by Majeed function score, and fracture reduction was evaluated according to Mears-Velyvis radiological evaluation criterion.Results:All patients were followed for 24-72 months [(46.0±18.5)months]. In ilioinguinal group and lateral-rectus group, the operation time was (295.0±95.3)minutes and (165.1±52.2)minutes, respectively ( P<0.05), and the intraoperative blood loss was (190.0±65.2)ml and (225.7±92.0)ml, respectively ( P>0.05). In ilioinguinal group, the development of bilateral iliac wings was asymmetric in 3 patients. In lateral-rectus group, fracture-dislocation of epiphyseal plate together with abnormal development of iliac wing occurred in 1 patient, but had no effects on the function of lower limbs. According to Majeed function score at the last follow-up, the pelvic function in ilioinguinal approach group was rated as excellent in 1 patient, good in 2, fair in 1 and poor in 1, with the excellent and good rate of 60%, while the pelvic function in lateral-rectus group was excellent in 4 patients, good in 1, fair in 2 and poor in none, with the excellent and good rate of 71% ( P>0.05). According to Mears-Velyvis radiological evaluation criterion at the last follow-up, the fracture reduction in ilioinguinal group was rated as satisfied in 3 patients and dissatisfied in 2 patients, with the satisfaction rate of 60%, while the fracture reduction in lateral-rectus group was satisfied in 7 patients and dissatisfied in none, with the satisfaction rate of 100% ( P>0.05). Conclusions:For Torode-Zieg type IV pelvic fracture in toddles, both surgical approaches can complete the reduction and fixation. However, the lateral-rectus approach has shorter operation time and less damage to the epiphyseal structure around the pelvis than the ilioinguinal approach.

Mussel-inspired functionalization of electrospun scaffolds with polydopamine-assisted immobilization of mesenchymal stem cells-derived small extracellular vesicles for enhanced bone regeneration.

Mesenchymal stem cells-derived small extracellular vesicles (MSCs-sEV) have shown promising prospects as a cell-free strategy for bone tissue regeneration. Here, a bioactive MSCs-sEV-loaded electrospun silk fibroin/poly(ε-caprolactone) (SF/PCL) scaffold was synthesized via a mussel-inspired immobilization strategy assisted by polydopamine (pDA). This pDA modification endowed the as-prepared scaffold with high loading efficiency and sustained release profile of sEV. In addition, the fabricated composite scaffold exhibited good physiochemical, mechanical, and biocompatible properties. In vitro cellular experiments indicated that the MSCs-sEV-loaded composite scaffold promoted the adhesion and spreading of preosteoblast and endothelial cells, as well as enhanced osteogenic differentiation and angiogenic activity. In vivo experiments showed that the functionalized electrospun scaffolds promoted bone regeneration in a rat calvarial bone defect model. Results suggest that the developed MSCs-sEV-anchored pDA-modified SF/PCL electrospun scaffolds possess high application potential in bone tissue engineering owing to their powerful pro-angiogenic and -osteogenic capacities, cell-free bioactivity, and cost effectiveness.

Incorporation of Layered Rectorite into Biocompatible Core-Sheath Nanofibrous Mats for Sustained Drug Delivery.

Searching for drug carries with controlled release and good biocompatibility has always been one of the research hotspots and difficulties. Herein, core-sheath nanofibrous mats (NFs) consisting of biocompatible poly(ethylene oxide) (PEO, core) and poly(l-lactic acid) (PLLA, sheath) for drug delivery were fabricated via coaxial electrospinning strategy. The nontoxic layered silicate rectorite (REC) with 0.5-1 wt % amount was introduced in the sheath for sustained drug delivery. Layered REC could be intercalated with PLLA macromolecule chains, leading to the densified structure for loading and keeping doxorubicin hydrochloride (DOX) while reversibly capturing and releasing DOX to delay the drug migration due to its high cation activity. The addition of REC in NFs could delay the initial burst release of DOX and prolong the residence time from 12 to 96 h. Moreover, DOX-loaded core-sheath NFs had in vitro culture with strong antitumor activity, which was confirmed by cytotoxicity results and live and dead assay. HepG2 tumor-bearing xenograft further demonstrated the tumor-suppression effect and the excellent safety of the DOX-loaded core-sheath NFs in vivo. The constructed NFs as drug carriers showed great potential in the local treatment of solid tumors.

Biomimetic Silk Fibroin Hydrogels Strengthened by Silica Nanoparticles Distributed Nanofibers Facilitate Bone Repair.

Various materials are utilized as artificial substitutes for bone repair. In this study, a silk fibroin (SF) hydrogel reinforced by short silica nanoparticles (SiNPs)-distributed-silk fibroin nanofibers (SiNPs@NFs), which exhibits a superior osteoinductive property, is fabricated for treating bone defects. SF acts as the base part of the composite scaffold to mimic the extracellular matrix (ECM), which is the organic component of a native bone. The distribution of SiNPs clusters within the composite hydrogel partially mimics the distribution of mineral crystals within the ECM. Incorporation of SiNPs@NFs enhances the mechanical properties of the composite hydrogel. In addition, the composite hydrogel provides a biocompatible microenvironment for cell adhesion, proliferation, and osteogenic differentiation in vitro. In vivo studies confirm that the successful repair is achieved with the formation of a large amount of new bone in the large-sized cranial defects that are treated with the composite hydrogel. In conclusion, the SiNPs@NFs-reinforced-hydrogel fabricated in this study has the potential for use in bone tissue engineering.

Bi-layered Composite Scaffold for Repair of the Osteochondral Defects.

Objective: Osteochondral defect presents a big challenge for clinical treatment. This study aimed at constructing a bi-layered composite chitosan/chitosan-ß-tricalcium phosphate (CS/CS-ß-TCP) scaffold and at repairing the rat osteochondral defect. Approach: The bi-layered CS/CS-ß-TCP scaffold was fabricated by lyophilization, and its microstructure was observed by a scanning electron microscope. Chondrocytes and bone marrow stem cells (BMSCs) were seeded into the CS layer and the CS-ß-TCP layer, respectively. Viability and proliferation ability of the cells were observed under a confocal microscope. After subcutaneous implantation, the chondrogenic ability of the CS layer and osteogenic ability of the CS-ß-TCP layer were evaluated by immunofluorescence. Then, the bi-layered scaffolds were implanted into the rat osteochondral defects and the harvested samples were macroscopically and histologically evaluated. Results: The bi-layered CS/CS-ß-TCP scaffold exhibited the distinctive microstructures for each layer. The seeded chondrocytes in the CS layer could maintain the chondrogenic lineage, whereas BMSCs in the CS-ß-TCP layer could continually differentiate into the osteogenic lineage. Moreover, cells in both layers could maintain well viability and excellent proliferation ability. For the in vivo study, the newly formed tissues in the bi-layered scaffolds group were similar with the native osteochondral tissues, which comprised hyaline-like cartilage and subchondral bone, with better repair effects compared with those of the pure CS group and the blank control group. Innovation: This is the first time that the bi-layered composite CS/CS-ß-TCP scaffold has been fabricated and evaluated with respect to osteochondral defect repair. Conclusion: The bi-layered CS/CS-ß-TCP scaffolds could facilitate osteochondral defect repair and might be the promising candidates for osteochondral tissue engineering.

Electrospinning Nanofiber-Reinforced Aerogels for the Treatment of Bone Defects.

Objective: Application of aerogels in bone tissue engineering is an emerging field, while the reports of electrospinning nanofiber-reinforced aerogels are limited. This research aimed at fabricating the nanofiber-reinforced aerogels and evaluating their physiochemical and biological properties. Approach: The chitosan (CS) aerogels incorporated with cellulose acetate (CA) and poly (ɛ-caprolactone) (PCL) nanofibers were fabricated via ball milling and freeze-drying techniques. Scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectrum, X-ray photoelectron spectroscopy (XPS), compressive experiment, and in vitro experiment were conducted to assess their physiochemical properties and biological behavior. Results: The SEM examination showed that satisfying morphology was attained in the CA/PCL/CS aerogels with incorporation of CA/PCL nanofibers and CS solution. The results of FT-IR and XPS indicated the perfect incorporation of CA, PCL, and CS. A compressive experiment confirmed that the CA/PCL/CS aerogels enhanced the compressive modulus of the pure CS aerogel. For in vitro experiment, the CA/PCL/CS composite scaffolds were proven to possess better cytocompatibility compared with the pure CS. Also, cells on the CA/PCL/CS showed well-extended morphology and could infiltrate into a porous scaffold. Furthermore, confocal experiment revealed that the CA/PCL/CS could also promote the osteogenic differentiation of MC3T3-E1 cells. Innovation: This study fabricated the nanofiber-reinforced aerogels mainly to optimize the cell/material interaction of the pure CS scaffold. Conclusion: The CA/PCL nanofibers not only improved the mechanical property of the CS aerogel to some extent but also facilitated cell adhesion and osteogenic differentiation. Thus, it could be considered a promising candidate for bone tissue engineering.

Proteomic Analysis of Exosomes from Adipose-Derived Mesenchymal Stem Cells: A Novel Therapeutic Strategy for Tissue Injury.

Exosomes are extracellular membranous nanovesicles that mediate local and systemic cell-to-cell communication by transporting functional molecules, such as proteins, into target cells, thereby affecting the behavior of receptor cells. Exosomes originating from adipose-derived mesenchymal stem cells (ADSCs) are considered a multipotent and abundant therapeutic tool for tissue injury. To investigate ADSC-secreted exosomes and their potential function in tissue repair, we isolated exosomes from the supernatants of ADSCs via ultracentrifugation, characterized them via transmission electron microscopy, nanoparticle tracking analysis, and Western blot analysis. Then, we determined their protein profile via proteomic analysis. Results showed that extracellular vesicles, which have an average diameter of 116 nm, exhibit a cup-shaped morphology and express exosomal markers. A total of 1,185 protein groups were identified in the exosomes. Gene Ontology analysis indicated that exosomal proteins are mostly derived from cells mainly involved in protein binding. Protein annotation via the Cluster of Orthologous Groups system indicated that most proteins were involved in general function prediction, posttranslational modification, protein turnover, and chaperoning. Further, pathway analysis revealed that most of the proteins obtained participated in metabolic pathways, focal adhesion, regulation of the actin cytoskeleton, and microbial metabolism. Some tissue repair-related signaling pathways were also discovered. The identified molecules might serve as potential therapeutic targets for future studies.

Controlled release of adenosine from core-shell nanofibers to promote bone regeneration through STAT3 signaling pathway.

Adenosine (Ade) has been identified to stimulate bone formation. However, the use of Ade is severely limited by the accompanying side effects and its very short half-life in vivo. This study aimed to fabricate an efficient drug-delivery system to reduce the undesirable side effects and enable the clinical application of Ade for treating large bone defects. The fabricated poly(ε-caprolactone) (PCL)/Ade-polyvinyl alcohol (PVA)(0.3/0.4) nanofibrous mats with 0.3:0.4 (w/w) ratio of Ade and PVA showed a sustained and controlled release of Ade and facilitated the osteogenic differentiation of bone mesenchymal progenitor cells (BMSCs). A larger amount of newly formed bone was observed in vivo in the cranial defects of the PCL/Ade-PVA(0.3/0.4) group compared with those of the non-loaded PCL/PVA nanofibrous mats at 4 and 8 weeks after surgery. Moreover, it is the first time to confirm that Ade mediates the osteogenesis of rat BMSCs through the STAT3 signaling pathway and restrains the osteoclastogenesis of rat bone-marrow macrophages (BMMs). These results suggested that this coaxial drug-delivery system loaded with Ade provided a promising and clinically relevant platform to controlled-release Ade and address large bone defects.

Effect of hybrid intensity modulated radiotherapy on the immune function of patients with locally advanced breast cancer surgery and efficacy observation / 肿瘤研究与临床

Objective:To investigate the effect of hybrid intensity modulated radiotherapy (Hy-IMRT) on immune function in patients with locally advanced breast cancer surgery and the treatment efficacy.Methods:A total of 94 patients with locally advanced breast cancer who underwent modified radical mastectomy for breast cancer and required postoperative radiotherapy in Changzhou Cancer Hospital in Jiangsu Province from January 2015 to January 2017 were selected. The patients were divided into Hy-IMRT group (observation group, 47 cases) and three-dimensional conformal radiotherapy (3DCRT) group (control group, 47 cases) according to the random number table method. The dose and related radiophysical parameters of the respective target areas of the two groups, adverse reactions during and after radiotherapy, cytokines and T lymphocyte subsets before and after radiotherapy, 3-year local recurrence rate, distant metastasis rate and mortality were observed and compared between the two groups.Results:The dose obtained by 95% (D 95%) [(4 945.6±36.1) Gy vs. (4 754.0±35.6) Gy] and target area conformity (CI) of the target volume (0.7±0.1 vs. 0.5±0.1) in the observation group were greater than those in the control group, and the differences were statistically significant (both P<0.05); the target volume of 110% of the prescription dose (V 110%) [(1.6±0.5) cm 3 vs. (8.4±1.2) cm 3], the target volume of more than 105% of the prescription dose (V 105%) [(19.3±3.5) cm 3 vs. (26.6±5.6) cm 3] and the heterogeneity index (HI) (1.1±0.1 vs. 1.3±0.1) in the observation group were all smaller than those of the control group, and the differences were statistically significant (all P < 0.05). The incidence of acute skin adverse reactions [53.2% (25/47) vs. 74.5% (35/47)] and the incidence of bone marrow suppression [40.4% (19/47) vs. 70.2% (33/47)] in the observation group were lower than those in the control group, and the differences were statistically significant (both P < 0.05). There were no significant differences in levels of interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), CD4 +, CD8 +, and CD4 +/CD8 + between the two groups before radiotherapy (all P > 0.05). At the end of radiotherapy, the levels of IL-6, TNF-α and CD8 + were higher in both groups than before radiotherapy (all P < 0.05), and CD4 + and CD4 +/CD8 + were lower than before radiotherapy (both P < 0.05). The levels of IL-6, TNF-α and CD8 + in the observation group were lower than those in the control group, while the CD4 + and CD4 +/CD8 + were higher than those in the control group (all P < 0.05). The 3-year local recurrence rate [34.04% (16/47) vs. 42.55% (20/47)], distant metastasis rate [25.53% (12/47) vs. 38.30% (18/47)] and mortality rate [14.89% (7/47) vs. 19.15% (9/47)] in the observation group were lower than those in the control group, but the differences were not statistically significant (all P > 0.05). Conclusion:Compared with 3DCRT, the Hy-IMRT has less effect on the immune function of locally advanced breast cancer patients after modified radical resection, and the incidences of acute skin reaction and bone marrow adverse reaction are low.

Characterization of inthomycin biosynthetic gene cluster revealing new insights into carboxamide formation / 中国天然药物

Inthomycins are polyketide antibiotics which contain a terminal carboxamide group and a triene chain. Inthomycin B (1) and its two new analogues 2 and 3 were isolated from the crude extract of Streptomyces pactum L8. Identification of the gene cluster for inthomycin biosynthesis as well as the N-labeled glycine incorporation into inthomycins are described. Combined with the gene deletion of the rare P450 domain in the NRPS module, a formation mechanism of carboxamide moiety in inthomycins was proposed via an oxidative release of the assembly chain assisted by the P450 domain.