A Nature-Inspired Versatile Bio-Adhesive.

The application of most hydrogel bio-adhesives is greatly limited due to their high swelling, low underwater adhesion, and single function. Herein, a spatial multi-level physical-chemical and bio-inspired in-situ bonding strategy is proposed, to develop a multifunctional hydrogel bio-glue using polyglutamic acid (PGA), tyramine hydrochloride (TYR), and tannic acid (TA) as precursors and 4-(4,6-dimethoxytriazine-2-yl) -4-methylmorpholine hydrochloride(DMTMM) as condensation agent, which is used for tissue adhesion, hemostasis and repair. By introducing TYR and TA into the PGA chain, it is demonstrated that not only can the strong adhesion of bio-glue to the surface of various fresh tissues and wet materials be realized through the synergistic effect of spatial multi-level physical and chemical bonding, but also this glue can be endowed with the functions of anti-oxidation and hemostasis.

Supersaturation and Precipitation Applicated in Drug Delivery Systems: Development Strategies and Evaluation Approaches.

Supersaturation is a promising strategy to improve gastrointestinal absorption of poorly water-soluble drugs. Supersaturation is a metastable state and therefore dissolved drugs often quickly precipitate again. Precipitation inhibitors can prolong the metastable state.

Piezoelectric Effect of Antibacterial Biomimetic Hydrogel Promotes Osteochondral Defect Repair.

The lack of vascular tissue and the low metabolism and biological activity of mature chondrocytes lead to the low regeneration ability of articular cartilage. People try to solve this problem through various methods, but the effect is not very ideal. Inspired by the piezoelectric effect of collagen in cartilage tissue, this work focused on the design of a biomimetic hydrogel by introducing piezoelectric materials and silver nanowires into hydrogel to endow them with piezoelectric and antibacterial properties to promote tissue regeneration.

A case of musculi peronaeus tertius anatomic variation.

In the routine dissections study for medical postgraduates, a rare anatomical variation between the right leg and the ankle was observed on the Asian male cadaver. The peronaeus tertius muscle in this cadaver's right leg divided into two tendons: the first tendon was attached to the base of the fifth metatarsal bone, and the second tendon was inserted into the base of the fourth metatarsal bone. The purpose of this paper is to provide detailed anatomical case reports, and to discuss the possible causes and mechanisms of the variation by reviewing relevant literature, so as to provide some reference for future anatomical and clinical related disease research.

Optimal regenerative repair of large segmental bone defect in a goat model with osteoinductive calcium phosphate bioceramic implants.

So far, how to achieve the optimal regenerative repair of large load-bearing bone defects using artificial bone grafts is a huge challenge in clinic. In this study, a strategy of combining osteoinductive biphasic calcium phosphate (BCP) bioceramic scaffolds with intramedullary nail fixation for creating stable osteogenic microenvironment was applied to repair large segmental bone defects (3.0 cm in length) in goat femur model.

Effects of cervical rotatory manipulation on the cervical spinal cord: a finite element study.

Background: Little information is available concerning the biomechanism involved in the spinal cord injury after cervical rotatory manipulation (CRM). The primary purpose of this study was to explore the biomechanical and kinematic effects of CRM on a healthy spinal cord.

Methods: A finite element (FE) model of the basilaris cranii, C1-C7 vertebral bodies, nerve root complex and vertebral canal contents was constructed and validated against in vivo and in vitro published data.

By Endowing Polyglutamic Acid/Polylysine Composite Hydrogel with Super Intrinsic Characteristics to Enhance its Wound Repair Potential.

In this study, multifunctional porous composite hydrogels are prepared via composite technology and using poly(glutamic acid) and (polylysine) as precursors, casein as foaming agent, and calcium ions as coagulant. The results show that the as-prepared hydrogels have high porosity and water absorbency, and good mechanical, inherent antibacterial, and bioadhesive properties. The results show such high water absorption, bioadhesion, and porosity of the as-prepared hydrogel can effectively concentrate blood components and seal wounds better.

Mixed Modification of the Surface Microstructure and Chemical State of Polyetheretherketone to Improve Its Antimicrobial Activity, Hydrophilicity, Cell Adhesion, and Bone Integration.

Polyetheretherketone (PEEK) is becoming an attractive surgical implant material in the biomedical field. However, its hydrophobicity and biological inertia have seriously hindered its development in the field of biomaterials and application in clinic. In this work, a mixed modification approach of the surface structure and chemical state was proposed to improve hydrophilicity and bioactivity of PEEK and meanwhile endowed it with antimicrobial properties.

Constructing Gene-Enhanced Tissue Engineering for Regeneration and Repair of Osteochondral Defects.

In situ sustained release of endogenous growth factors from cells is a challenge for repair and regeneration of tissue. Although recombinant adenovirus vectors are an effective delivery system that can prolong the release of growth factors and is very suitable for the therapy of growth factors, these recombinant adenovirus vectors that are widely used at present have low safety and stability in terms of long-term expression. In this study, the above problems are solved by knocking out both E1 and E3 genes at the same time and directly inserting the gene fragments encoding target proteins after the inverted terminal repeats.

Joint construction of micro-vibration stimulation and BCP scaffolds for enhanced bioactivity and self-adaptability tissue engineered bone grafts.

The bone defects caused by trauma and disease have become a major difficulty in the treatment of clinical bone defects, and bone tissue engineering has become a promising treatment strategy. It was found that mechanical stimulation regulated the development of bone constructs by affecting the distribution and differentiation of cells on them. In this study, tissue-engineered bone grafts with enhanced bioactivity and self-adaptability were constructed by BMSCs and biphasic calcium phosphate (BCP) scaffolds under periodic micro-vibration stimulation (MVS) with a frequency of 40 Hz and a magnitude of 0.

A strategy using mesoporous polymer nanospheres as nanocarriers of Bcl-2 siRNA towards breast cancer therapy.

Small interference RNA (siRNA) has demonstrated unprecedented potential as a therapy for drug-resistant cancer. However, efficient cellular delivery is still a challenge due to hydrolytic sensitivity and poor cellular uptake of siRNA. Strategies to conjugate siRNA to the delivery vehicle and activate innate immunity have shown low in vivo efficacy.

Biomimetic Bacterial Cellulose-Enhanced Double-Network Hydrogel with Excellent Mechanical Properties Applied for the Osteochondral Defect Repair.

Although hydrogels based on biopolymers show many advantages, their low mechanical properties limit their applications in osteochondral tissue engineering. In this study, one part of our work aimed at preparing a high strength biohydrogel by using a double-network (DN) hydrogel system, which consisted of two interpenetrating polymer networks composed of γ-glutamic acid, lysine, and alginate, and meanwhile by incorporating bacterial cellulose into the DN structures. The results showed that compression modulus of the resultant hydrogel (0.

A single integrated osteochondral in situ composite scaffold with a multi-layered functional structure.

This work focuses on the optimization design of a functional biomimetic scaffold for the repair of osteochondral defects and includes the study of single integrated osteochondral tissue engineering scaffolds with a multi-layered functional structure. Rabbit model experiments were used to evaluate the repair of osteochondral defects. The results revealed that good integration was achieved both at the interfaces between the scaffold material and the host tissue and between the newly formed subchondral bone and cartilage.

Hybrid use of combined and sequential delivery of growth factors and ultrasound stimulation in porous multilayer composite scaffolds to promote both vascularization and bone formation in bone tissue engineering.

In this study, a multilayer coating technology would be adopted to prepare a porous composite scaffold and the growth factor release and ultrasound techniques were introduced into bone tissue engineering to finally solve the problems of vascularization and bone formation in the scaffold whilst the designed multilayer composite with gradient degradation characteristics in the space was used to match the new bone growth process better. The results of animal experiments showed that the use of low intensity pulsed ultrasound (LIPUS) combined with growth factors demonstrated excellent capabilities and advantages in both vascularization and new bone formation in bone tissue engineering. The degradation of the used scaffold materials could match new bone formation very well.

Porous nanoapatite scaffolds synthesized using an approach of interfacial mineralization reaction and their bioactivity.

There is a growing interest in the use of calcium phosphate, used to fabricate porous scaffolds for bone tissue regeneration and repair. However, it is difficult to obtain interconnected pores with very high porosity and to engineer the topography of the pore walls for calcium phosphate ceramic scaffolds. In this study, a novelty method interfacial mineralization reaction was used to fabricate porous nano-calcium phosphate ceramic scaffolds with three-dimensional surface topography of walls, which was tuned using different surfactants; using this method, porous scaffolds with different shapes were obtained, which demonstrates that interfacial mineralization reaction is not only a good method to prepare porous ceramic scaffolds of calcium phosphate but also an efficient approach to engineer the topography of the pore walls.