C-arm based surgical navigation is a typical computer assisted surgery technique; it takes XR II images as carriers,and helps surgeons with high quality operation by demonstrate operating entity virtually. In this paper, we focused on some issues concerning C-arm based surgical navigation technique, including the system operation theory, key techniques, consisting parts,main application, advantages and shortcomings. On this basis, we also discussed the development trend of this kind of surgical navigation technique.

Objective To analyze the practical experiences of design and its clinical application of custom-made tumor prostheses of knee. Methods A retrospective study of 41 cases of distal femur or proximal tibia tumors treated surgically from June 1999 to October 2002, was carried out. In the study, there were 29 males and 12 females aging from 11 to 69 years with an average of 35.0 years. The location of tumors were at distal femur in 23 cases and 9 cases at proximal tibia, of which 15 were osteosarcoma, 13 giant cell tumor, 3 chondrosarcoma, 5 solitary metastatic bone tumor, and 1 each of fibrosarcoma, malignant fibrohistocytoma, Ewings sarcoma, small round cell sarcoma and syndesmofibroma. The custom-made semi-constrained knee prosthesis with femoral or tibial component was implanted after extra-capsular resection of the tumor bone segment. A special femoral component with elongated construction was used in an 11-year old case for further femur lengthening. Resection of femoral artery involved by tumor and reparation by great saphenous vein was performed in one case. Results The operations of the 41 cases were all smoothly performed. 33 cases were followed up from 8 to 37 months with an average of 20.2 months. The daily life ability was recovered in 3 months after the operation. Among them, no loosening or failure of the prostheses was found, and local recurrence was found in 2 cases and distant metastasis in 3 cases. The design of knee prosthesis could provide some proper internal/external rotation and adduction/abduction movements accompanying with the flexion and extension of the knee joint without affecting the stability of the joint. For the case of proximal tibia tumor, a special design and surgical technique was developed to provide the reconstruction of patellar ligament insertion with rather good results; and the recovery of knee extension and stability were satisfied. Conclusion The custom-made semi-constrained tumor prosthesis of knee could be used as an effective method for the limb-savage management either the distal femur or proximal tibia tumor cases.

The orthopedics implants failure management system has been put forward according to the present status. The function of the system and typical failure case reasoning route also have been described. Furthermore, the analysis process has been presented by illustrating a typical failure case analysis.
Medical Records Systems, Computerized ; Orthopedic Procedures ; instrumentation ; Prosthesis Design ; Prosthesis Failure ; Software Design

Seeing that there are several defects in the calibration target currently used in C-arm-based surgical navigation system, we propose an improved design of calibration target based on the theory of generalized mapping. The method of design is introduced, the analysis is made, and the results are reported. The newly designed calibration target is of low manufacturing difficulty and cost; with the new calibration target, the running efficiency and the image quality of the whole navigation system could be improved. The new calibration target is found to be of several advantages over the currently used ones; it is feasible and is under manufacturing already.
Calibration ; standards ; Computer-Aided Design ; Equipment Design ; Image Processing, Computer-Assisted ; instrumentation ; Surgery, Computer-Assisted ; instrumentation ; Tomography, X-Ray Computed ; instrumentation

OBJECTIVEUse proteomic technique to research the effects of Qishenyiqi formula in acute myocardial infarcted rats, and further explore its protein-level mechanism.

METHODThe rat hearts of sham, myocardial infarcted and Qishenyiqi formula treated groups were collected. Analyzing and comparing the differences of protein expressions in each groups with two-dimensional electrophoresis, computer-assisted image analysis and matrix-assisted laser desorption/ionization mass spectrometry.

RESULTCompared with myocardial infarcted group, there were 14 protein expressions changed in Qishenyiqi formula treated group. The result showed that 9 protein expressions were up-regulated, and 5 ones were down-regulated significantly. These proteins are associated with energy metabolism, mitochondrial function, oxidative stress, cytoskeleton and others.

CONCLUSIONMyocardial protective effects of Qishenyiqi formula in myocardial infarcted procedure might be closely related to the recovery of energy supply, the reduction of oxidative stress, as well as the promotion of cell recovery.

Animals ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Electrophoresis, Gel, Two-Dimensional ; Gene Expression Regulation ; drug effects ; Male ; Myocardial Infarction ; drug therapy ; metabolism ; Myocardium ; metabolism ; Proteomics ; methods ; Rats ; Rats, Sprague-Dawley

Hematopoietic stem cells (HSC) are a class of stem cells with self-renewal and multipotent differentiation into a variety of blood cells and are most thoroughly studied, maturely applied in the clinic adult stem cell. Function of HSC is closely associated with metabolic regulation. The metabolic state mainly maintains HSC living in hypoxic bone marrow microenvironment depending on glycolysis for energy metabolism, and keeping low reactive oxygen species (ROS) level. Proteins like Hif-1, FoxO3, ATM, PTPMT1 protect HSC from ROS injury, maintaining HSC in hypoxic state. In addition, glucose metabolism-related enzymes, glutamine, fatty acid oxidation, purine and amino acid metabolism also play important roles in metabolic regulation of HSC. In this review the research progress on metabolism regnlation mechanisms of HSC is summurized, focusing on the mechanisms releted with oxydation metabolism regulation, carbohydrate metabolism level, purine metabolism and aminoacide metabolism.
Bone Marrow ; Cell Differentiation ; Hematopoietic Stem Cells ; Oxidation-Reduction ; Reactive Oxygen Species

OBJECTIVE: To study the effects of the neuro-microenvironment on the mass of mitochondria in hematopoietic stem and progenitor cells (HSPC), and to understand the potential mechanisms how nerve regulates HSPC. METHODS: 6-hydroxydopamine (6-OHDA) and capsaicin were used to interfere with the function of sympathetic nerve and nociceptive nerve in mitochondria-GFP reporter mice, respectively. The fluorescence intensity of GFP in bone marrow and spleen was measured by flow cytometry. The GFP median fluorescence intensity (MFI) of HSPC in normal bone marrow and spleen was analyzed and compared. The changes of the mitochondrial mass in HSPCs in each group after denervation were compared. RESULTS: Hematopoietic stem cells (HSC) had the highest mito-GFP MFI in steady-state (49 793±1 877), and the mito-GFP MFI gradually decreased during the differentiation of HSCs. Compared with control group, pharmaceutical nociceptive denervation significantly increased the mito-GFP MFI of bone marrow multipotent progenitor-1 (MPP1, 50 751±420 vs 44 020±510) and LKS^- cells (15 673±65 vs 13 979±103); pharmaceutical sympathetic denervation significantly reduced the mito-GFP MFI of bone marrow LKS⁺ cells (21 667±351 vs 29 249±973). CONCLUSION Sympathetic and nociceptive nerves can regulate the mass of mitochondria in HSPC and affect the function of HSPCs.
Animals ; Mice ; Hematopoietic Stem Cells ; Bone Marrow/metabolism* ; Cell Differentiation ; Mitochondria ; Pharmaceutical Preparations/metabolism*

OBJECTIVE: To investigate the role of bone marrow vascular niche in the development of MLL-AF9 acute myeloid leukemia (AML). METHODS: Transplantation experiments were performed to establish non-radiated MLL-AF9 AML model; the half-bone immunofluorescence staining and tile-scan imaging of two-photon confocal microscopy were used to obtain the data of 3 main bone marrow niche cells; flow cytometry analysis was performed to characterize leukemia cells in different anatomical sites. RESULTS: In the early stage of MLL-AF9 AML, the proportion of leukemia cells in the metaphysis of the femur was significantly higher than that in the diaphysis. The detection of apoptosis and proliferation rate of leukemia cells showed that the percentage of leukemia cells in metaphysis significantly decreased, and the proliferation (S/G/M phase) was also significantly more active. These different features of leukemia cells may relate with different bone marrow microenvironment. The image data of 3 major components of bone marrow niche (endothelial cells, endosteum, megakaryocytes) showed different distribution of blood vessels in metaphysis and diaphysis. Furtherly comparing the spatial distance between leukemia cells and endothelial cells, endosteum, megakaryocytes indicated that leukemia cells are closer to the blood vessels, suggesting the important role of blood vessels in the development of leukemia. Glucose uptake assays and intracellular ROS detection showed that the supportive role of blood vessels for leukemia cells did not related with nutrient metabolism pathway. CONCLUSION The vascular niche plays an important role in the development of leukemia, and does not relate with the transport of nutrients and the elimination of metabolic waste, instead, which may relate with perivascular cytokines or other vascular functions.
Acute Disease ; Apoptosis ; Bone Marrow ; Bone Marrow Cells ; Humans ; Leukemia, Myeloid, Acute ; Myeloid-Lymphoid Leukemia Protein ; Oncogene Proteins, Fusion

There are more than 150 types of chemical modifications in RNA, mainly methylation, which are widely distributed in all kinds of RNA, including messenger RNA, transfer RNA, ribosomal RNA, non-coding small RNA and long non-coding RNA. In recent years, the identification of RNA methylation modification enzymes and the development of high-throughput sequencing technology at transcriptome level laid a foundation for revealing the expression and function of genes regulated by chemical modification of RNA. In this review, the most recent advances of RNA methylation, especially N6-methyladenosine (m
Adenosine/metabolism* ; Hematopoiesis ; Humans ; Methylation ; RNA/metabolism*

ObjectiveTo study the mechanism of Shenbai Jiedu prescription inhibiting the proliferation of HCT116 colorectal cancer （CRC） cells by regulating the phosphatase and tensin homolog deleted on chromosome ten （PTEN）/phosphatidylinositol 3-kinase （PI3K）/ protein kinase B （Akt） signaling pathway. MethodShenbai Jiedu prescription was extracted by water extraction and alcohol precipitation to prepare freeze-dried powder. HCT116 cells were cultured in vitro， and treated with different concentrations of Shenbai Jiedu prescription （2， 4， 8， 16 g·L^-1）. The inhibitory effect of Shenbai Jiedu prescription on the proliferation of HCT116 cells was tested by methyl thiazolyl tetrazolium （MTT）. Real-time quantitative PCR was used to detect the mRNA expression levels of PTEN， PI3K， Akt， glycogen synthase kinase-3β （GSK-3β）， c-Myc， survivin and Cyclin D₁. Western blot was employed to measure the protein expression levels of PTEN， phosphorylated PTEN （p-PTEN）， PI3K， Akt， phosphorylated Akt （p-Akt）， GSK-3β， phosphorylated GSK-3β （p-GSK-3β）， c-Myc， survivin and Cyclin D₁， β-catenin nuclear import was explored by immunofluorescence assay. ResultCompared with the control group， Shenbai Jiedu prescription inhibited the proliferation of HCT116 cells in a dose-dependent manner （P<0.01）. Compared with the control group， the mRNA expression levels of PTEN and GSK-3β were up-regulated whereas those of PI3K， Akt， c-Myc， survivin and CyclinD₁ were down-regulated after treatment with Shenbai Jiedu prescription （P<0.01）. The protein expression levels of PTEN， p-PTEN and GSK-3β were up-regulated whereas those of PI3K， Akt， p-Akt， GSK-3β， p-GSK-3β， c-Myc， survivin and CyclinD₁ were down-regulated （P<0.05， P<0.01）. Immunofluorescence assay showed that Shenbai Jiedu prescription suppressed β-catenin nuclear import in HCT116 cells. ConclusionShenbai Jiedu prescription inhibited the proliferation of HCT116 cells via the mechanism of regulating the PTEN/PI3K/Akt signaling pathway.