Most medical postgraduates desire to develop their research mentality and experiment skills and become capable medical students with potentialities and innovation consciousness.Medical postgraduates can be classified into academic, general, and clinical types based on their needs, education background, experiences and personal abilities, while their supervisors fall into high-, medium-, and low-expectation types according to their research abilities and demands.Cross-pairing analysis shows that a high-level cooperation can be achieved when the type of a postgraduate matches that of his supervisor, otherwise a low-level cooperation may result.Therefore, it is essential to optimize the two-way choice system between postgraduates and supervisors, establish a moral code for supervisors and academic standards for postgraduates, and further enhance their interaction.A new relationship should be formed between medical postgraduates and supervisors, which is postgraduate-centered, emphatic on conversation, discussion, equality, and mutual trust and respect, and capable of promoting the harmonious development of academic activities.

BACKGROUND:No ideal drugs can be used in the prevention and treatment of aseptic loosening of artificial joints. Some researchs showed that erythromycin has strong inhibitory effects on periprosthetic osteolysis. Its antibacterial activity, however, limits its application in artificial joint loosening prevention. LY267108 is a new type of erythromycin derivatives, eliminates the antibacterial activities, and retains the anti-inflammatory activity.
OBJECTIVE:To evaluate inhibitory effect of LY267108 on nuclear factor kappa B during osteoclast activation.
METHODS:RANKL and macrophage colony-stimulating factor were added to RAW264.7 cellline of a mouse model induced by osteoclasts. Simultaneously, different concentrations of alendronate sodium, erythromycin and LY267108 were cocultured for 48 hours. The activity of nuclear factor kappa B and content of intracytoplasmic inhibitory subunit of nuclear factor kappa B alpha were measured by electrophoretic mobility shift assay and western blot assay.
RESULTS AND CONCLUSION:LY267108 has a strong inhibitory effect on nuclear factor kappa B. 10 mg/L LY267108, 25 mg/L erythromycin and 10 mg/L alendronate sodium had similar inhibitory effects on nuclear factor kappa B, which was obviously stronger than 10 mg/L erythromycin. However, 25 mg/L LY267108 had strongest inhibitory effects. No significant difference in intracytoplasmic inhibitory subunit of nuclear factor kappa B alpha levels was detected among 10 mg/L LY267108, 25 mg/L erythromycin and 10 mg/L alendronate sodium groups, but was stil apparently higher than 10 mg/L erythromycin group. Levels of intracytoplasmic inhibitory subunit of nuclear factor kappa B alpha were highest in the 25 mg/L LY267108 group. Results indicated that LY267108 in the process of osteoclast activation had stronger inhibitory effects on nuclear factor kappa B compared with erythromycin, and its safety was higher than alendronate sodium. Simultaneously, LY267108 did not have antimicrobial activity, and became a potential ideal drug for prevention and treatment of aseptic loosening of artificial joints. However, the inhibitory effects of LY267108 on the degradation of inhibitory subunit of nuclear factor kappa B alpha would be a mechanism of inhibiting the activation of nuclear factor kappa B.

As one of the most catastrophic complications, prosthetic joint infection remains one of the most stubborn medical problems.However, the biomarkers and laboratory tests commonly used often exhibit either a low sensitivity or a low specificity, which makes it still difficult to diagnose.Therefore, we summarize a number of recent new developments home and abroad, and overview from the aspects of serological markers, synovial fluid markers, radionuclide imaging methods, preoperative periprosthetic tissue biopsy, in-traoperative periprosthetic tissue culture, histological analysis of periprosthetic tissue and new molecular technology.

Melanoma inhibitory activity protein(MIA),also referred to as cartilage-derived retinoic acid-sensitive protein(CD-RAP),is expressed not only in malignant melanoma,but also in chondrocytes.MIA/CD-RAP act as a biological marker for the evaluation of the status of cartilage in the study of cartilage destruction.This article reviews the biochemistry,construction,physiological function of MIA/CD-RAP in cartilage destruction and the research progress in these aspects.

Osteogenic protein-1(OP-1),also referred to as bone morphogenetic protein-7(BMP-7),has the effective osteoinduction.In reconstructive surgery of the hip,OP-1 could induce greater and earlier new bone formation,accelerate the incorporation of the graft and host-bone,and enfance the fixation of the plant.The characteristics in the molecular biology and it's application in reconstructive surgery of the hip was reviewed.

Damaged articular cartilage has a limited intrinsic capacity to heal itself,especially in adults,It represents a clinical challenge.Novel gene therapy can introduce particular beneficial gene into the seeded sells and express growth factors or other therapy proteins at the repair site.Gene therapy focuses on selecting proper gene,target cells and the transferring systems. The tissue engineering cartilage with gene-modified seeding cells and transferring objective gene to target sells locally present new therapeutic regimens for repairing defects in articular cartilage.

The hallmark of osteoarthnitis(OA) is the loss of articular cartilage caused by an imbalance between cartilage synthesis and degredation over a variable period of time.IL-1 plays an important role in the course.The IL-1receptor antagonist(IL-Ra) specific against IL-1 is becoming a pivot of wide attention.The article offers a review of the relationship between the IL-1Ra and OA.

Tissue engineering has been a newly developed discipline which represents the new direction of biological medicine engineering.With evergrowing researches on the reparation of bone defect by tissue engineering,great success has been achieved in this field.The three important elements of bone tissue engineering are seed cells,cytokines and cellular biological scaffolds.Bioceramic is an important part of bioactive frame applied widely in tissue engineering.This paper presents a review of the application of bioceramic in the reparation of bone defect,which aims at promoting a systematic knowledge of the application of bioceramic in tissue engineering.

The bone morphogenetic protein(BMP),as a member of the transforming growth factor beta(TGF-?) family,plays a pivotal role in the formation,induction,maintenance and repair of the bone.The expression level of BMPs has a direct influence on the differentiation of mesenchymal osteoprogenitors and the regulation of osteoblastic features.Among BMPs,BMP-2 is the most widely studied and has the strongest activity in inducing bone formation.This article reviews the current advances in researches on BMP-2 for bone repair.

With the development of cartilage tissue engineering, how to achieve an ideal scaffold has become the difficult and hot spot in this study field. The scaffold for cartilage tissue engineering should provide with some special physical and biochemical properties, such as excellent biocompatibility, proper biodegradability, controlled porosity, adequate pore size and so on. Such properties are closely related to two factors, one is the materials used for scaffolds, the other is the fabrication technology. This review is concentrated on the present common fabrication technologies of three-dimensional porous scaffolds, and mainly introduces the following technologies: solvent casting/particulate leaching, phase separation/freeze-drying, hydrogels, gas foaming, electrospinning and rapid prototyping manufacturing. Those fabrication technologies' effects on structure and properties of scaffolds have been compared to summarize and analyze the advantages and disadvantages of every fabrication technology, and simultaneously prospect the developing tendency of fabrication technology in cartilage tissue engineering.