[Virtual preoperative planning and 3D-printed templates for pre-contoured plates in treatment of acetabular posterior wall fractures].

OBJECTIVE: To evaluate the feasibility and accuracy of virtual preoperative planning and 3D-printed templates for pre-contoured plates for the treatment of posterior wall fractures of the acetabulum. METHODS: A retrospective analysis of 29 patients with posterior acetabular wall fractures treated between August 2017 and March 2021 were divided into 2 groups based on whether to use preoperative virtual planning and 3D printed template. In 3D-printing group, there were 14 patients, including 10 males and 4 females； aged from 21 to 53 years old；CT-based virtual surgical planning was done using Mimics and 3-Matic software and 3D-printed templates for pre-contoured plates were adopted. In conventional group, there were 15 patients, including 10 males and 5 females；aged from 19 to 55 years old；conventional method of intra-operative contouring to adapt the plate to the fracture region was adopted. Blood loss, surgical time, radiographic quality of reduction, and hip function were compared between groups. RESULTS: The difference in operation time and intraoperative blood loss was significant（P<0.05）. Twenty-three patients were followed up from 12 to 30 months, and the fractures in both groups healed with a healing time of 3 to 6 months. At the last follow-up, the Merle d'Aubign-Postel score of the 3D printed group was lower than that of the conventional group（P<0.05）, with no significant differences in walking ability, hip mobility and total score（P>0.05）. In 3D printing group, 6 cases were excellent, 5 cases were good, 3 cases were fair；in conventional group, 5 cases were excellent, 5 cases were good, 4 cases were fair, 1 case was worse；no significant difference between two groups（P>0.05）. CONCLUSION: Virtual preoperative planning and 3D-printed templates for pre-contoured plates can reduce operative time and the blood loss of surgery, improve the quality of reduction. This method is efficient, accurate and reliable to treat acetabular posterior wall fractures.

[Effect of computer virtual technique combined with pelvic reduction frame in the treatment of type C pelvic fracture].

OBJECTIVE: To investigate the short-term clinical effect of the computer virtual technique combined with pelvic reduction frame in the treatment of complex pelvic fractures. METHODS: Thirty patients with Tile C pelvic fractures treated by percutaneous minimally invasive pelvic reduction frame from April 2018 to April 2020 were retrospectively analyzed, including 21 males and 9 females, aged from 19 to 57 (39.40±9.85) years old. The patient's pelvic CT DICOM data were imported into Mimics software to reconstruct the virtual fracture model. Virtual reduction and nail placement were carried out on the fracture model, and then simulated fluoroscopy was carried out to record the ideal fluoroscopy orientation and angle to guide the correct fluoroscopy during operation. The operation time, fluoroscopy times and intraoperative blood loss were recorded. The quality of fracture reduction was evaluated by Matta image score standard, and the postoperative function was evaluated by Majeed function score standard. RESULTS: All 30 patients achieved closed reduction and percutaneous screw fixation. According to Matta score, the excellent and good rate of fracture reduction was 93.3%(28/30). A total of 67 channel screws were inserted, and the excellent and good rate was 98.5%(66/67). The operation time was (173.54±79.31) min, fluoroscopy time was (90.81±41.11) times, intraoperative blood loss was (81.21±43.97) ml. All incisions healed at one stage without broken nails or re-displacement of fractures. All patients were followed up for 12 months. At the final follow-up, Majeed function score was 73 to 94(85.66±5.33) scores. CONCLUSION: Computer virtual technology combined with pelvic reduction frame could rapidly, accurately and safely reduce and fix unstable pelvic fractures. Computer virtualization could help surgeons to recognition and understanding pelvic fractures, pelvic reduction frame could improve the surgeon's ability to manage complex and unstable pelvic injuries.

Brain death and organ transplant legislation: analysis of 969 respondents by classroom questionnaire.

BACKGROUND: China has the largest potential market for organ transplants in the world, but it has not yet established brain death and organ transplant laws. We aimed to investigate the attitudes and suggestions of doctors, pharmacists, and civil servants concerning brain death, organ transplantation, and their respective legislation. METHODS: A questionnaire with 10 sections and 44 questions was designed and distributed. The effective questionnaire data were then recorded and checked for descriptive analysis. RESULTS: In 1400 questionnaires distributed, 1063 were responded and 969 of them were valid and analyzed. The respondents showed an incomplete understanding of brain death and organ transplantation laws. Seventy-four percent of the respondents recognized and accepted the standard of brain death. They agreed that legislation should be involved in the removal of organs for transplantation, the future use of organs, and insurance and compensation for the donor for possible health risks induced by organ removal. Of the 969 respondents, 92% considered it necessary to have legislation in brain death and organ transplantation, and 61% thought that it is time to legislate. CONCLUSIONS: Legislation for brain death and organ transplantation is urgent and timely in China. The laws must include the respective rights and obligations of patients, close relatives, and medical institutions. Educating the public about brain death and organ transplantation should also be encouraged in a variety of ways.

[Soluble expression, purification of bone morphogenetic protein-2 fragment and its antibody preparation].

The bone morphogenetic protein-2 (BMP-2) fragment (BMP-2omega, 606-846bp) cDNA was amplified from total RNA of SAOS-2 cells by using RT-PCR. The PCR product was then inserted into pET-28a (+) vector for constructing the expression plasmid that would be used to transform the host cell BL21(DE3). After IPTG inducing under different conditions, this BMP-2w protein could be expressed in high level as a soluble form, and purified by chelating column (Ni-NTA). Polyclonal antibody was made by immunizing mice with using purified protein, and the antiserum titer generated was 1: 6400 that was measured by ELISA. Western blot result showed that this antibody could bind to BMP-2 protein specifically. Above research result set up the basis for studying on the treatment of osteosarcoma.

Identification and characterization of the proteins in broth of stewed traditional Chinese yellow-feathered chickens.

Soups and broths are popular in the world due to their nutrition and flavor, and flavor compounds tend to be bound by the proteins in the soups and broth, influencing the flavor perception. Thus, identification of the major proteins in meat-based broth may present a basis for understanding protein adsorption of flavor compounds. The present study aimed to identify the major proteins in traditional Chinese chicken broth and to describe the structural changes of proteins during stewing (1, 2, or 3 h). As stewing time increased, protein content in the broth significantly increased. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) indicated that the macro-molecule proteins (>10 kDa) in the broth were mainly gelatin and actin and that the micro-molecule proteins fractions (<10 kDa) increased substantially. The gelatin had an ordered structure even after 3 h of stewing, as seen by circular dichroism (CD) spectroscopy. The presence of reactive sulfhydryl groups increased remarkably with stewing time. The surface hydrophobicity of the proteins significantly increased within 2 h then deceased slightly after 3 h. The intermolecular crosslinks, as indicated by dispersion index, increased remarkably, consistent with the result of atomic force microscopy (AFM), which together suggested that protein aggregation increased during stewing. These findings suggested that gelatin was the structural protein in the broth system and that intermolecular crosslinks functioned to maintain the broth system.

Biomechanical Comparison of Expansive Pedicle Screw and Polymethylmethacrylate-augmented Pedicle Screw in Osteoporotic Synthetic Bone in Primary Implantation: An Experimental Study.

STUDY DESIGN: Expansive pedicle screws (EPS) and polymethylmethacrylate-augmented pedicle screws (PMMA-PS) were inserted into osteoporotic synthetic bones, which were then tested by radiographic and biomechanical examinations. OBJECTIVE: To compare the stability of EPS and PMMA-PS with that of a conventional pedicle screw (CPS) in an osteoporotic synthetic bone. SUMMARY OF BACKGROUND DATA: It is a significant challenge for orthopedic surgeons performing transpedicular fixation in the osteoporotic spine. Prior studies have suggested that both EPS and PMMA-PS can increase the screw stability effectively. However, there are no biomechanical comparisons of EPS and PMMA-PS, especially in primary spinal surgery in osteoporosis. METHODS: Thirty osteoporotic synthetic bone blocks were divided into 3 groups randomly. A pilot hole was prepared in advance in all samples by the same method. Then, the CPS was inserted directly into the pilot hole in the CPS group; the hole in the PMMA-PS group was first filled with polymethylmethacrylate (PMMA; 2.5 mL) and then inserted with CPS, and the EPS was inserted directly into the blocks in the EPS group. Twenty-four hours later, x-ray and computed tomography examination and axial pullout tests were performed on all samples; the block destructions were then recorded, and the hole diameters were measured. RESULTS: In the CPS group, the screw was surrounded directly by the synthetic bone without any other materials, whereas in the PMMA-PS group, the screw was totally wrapped up by PMMA, and the PMMA was evenly distributed in the synthetic bone around the screw, indicating obvious improvement of the local density around the track. In the EPS group, the anterior part of the EPS presented an obvious expansion in synthetic bone and formed an unguiform structure pressing the surrounding synthetic bone. Screw stabilities in both the PMMA-PS and the EPS groups were significantly enhanced compared with those in the CPS group, and the screw stability in the PMMA-PS group was significantly higher than that in the EPS group. After the pullout tests, the block destructions were the most severe in the PMMA-PS group and the lightest in the CPS group. Hole diameters in the PMMA-PS and the EPS groups were significantly larger than that in the CPS group, whereas the diameter of the hole in the PMMA-PS group was significantly greater than that in the EPS group. CONCLUSIONS: EPS can significantly increase the strength of screw fixation compared with CPS in osteoporotic synthetic bone. Although EPS shows a weaker fixation strength compared with PMMA-PS in the osteoporotic synthetic bone, it may still provide an alternative option to prevent screw loosening in the clinical treatment of osteoporosis.

Inhibitors of Growth 1b Suppresses Peroxisome Proliferator-Activated Receptor-ß/δ Expression Through Downregulation of Hypoxia-Inducible Factor 1α in Osteoblast Differentiation.

Bone formation, a highly regulated developmental process, involves osteoblast differentiation, which is controlled by different important transcription factors. Recent evidence has suggested possible negative regulation of inhibitors of growth (ING) 1b on the osteoblast marker expression. The aim of this study is to examine the detailed mechanism by which the activity of ING1b inhibits osteoblast differentiation. In the current study, we investigated the function and mechanism by which ING1b inhibits osteoblast differentiation using C3H10T1/2 mesenchymal stem cells and MC3T3-E1 preosteoblasts. Real-time polymerase chain reaction and Western blotting showed that ING1b was decreased during osteoblast differentiation and ING1b overexpression markedly decreased alkaline phosphatase (ALP) activity, runt-related transcription factor 2 (Runx2) expression, and collagen type 1 synthesis, whereas ING1b silencing significantly upregulated ALP activity, Runx2 expression, and collagen type 1 synthesis. Further studies indicated that ING1b suppressed the expression of peroxisome proliferator-activated receptor (PPAR)-ß/δ in a hypoxia-inducible factor (HIF) 1α-dependent manner, while ING1b silencing significantly increased the expression of PPAR-ß/δ and HIF1α. Moreover, PPAR-ß/δ or HIF1α silencing significantly inhibited ALP activity, Runx2 expression, and collagen type 1 synthesis. These results demonstrated that ING1b is an important regulator of osteoblast differentiation and suppresses PPAR-ß/δ. Our study may provide additional insight into osteoblast differentiation and offer a potential new molecular target for osteoporosis.

Single level anterior interbody fusion and fixation in the treatment of thoracolumbar fractures.

BACKGROUND: Many surgical methods are available for repairing thoracolumbar fractures including short-segment internal fixation with posterior pedicle screws and anterior decompression and reduction. However, most methods are associated with significant surgical trauma and long postoperative recovery. The purpose of this study was to describe anterior single level interbody fusion and fixation for the repair of thoracolumbar fractures which may reduce surgical trauma and help speed recovery. METHODS: A group of 21 patients who underwent single level anterior interbody fusion and fixation from June 2006 to June 2011 were compared with a group of 21 patients who underwent double level anterior interbody fusion and fixation during the same period. The groups were compared with regard to operation time, intraoperative blood loss, fracture healing time, ratio of pre- to postoperative endplate height between adjacent vertebrae, Cobb angle in the sagittal plane, recovery of neural function, and internal fusion failure. RESULTS: The 2 groups were similar with the exception of fracture location (P=0.017). The patients who underwent the single level procedure had a shorter operation time (P < 0.001), less blood loss (P < 0.001), and shorter follow-up (P < 0.001). Both groups had significant improvement in Cobb angle at 1 week and 1 year after surgery, but there was no significant difference between the groups. Both groups also exhibited improvement in neurological function, and the difference in improvement between the groups was not significant. CONCLUSIONS: Single level intervertebral fusion and internal fixation for thoracolumbar fractures provides as satisfactory an outcome as the traditional approach, double level anterior interbody fusion and fixation, and reduces the degree of surgical trauma.

[On the history of the evolution of Evidence-based medicine and its revelation].

The notions of Evidence-based medicine developed through two phases, which successively looked into the doctor-patient relationship and decision-making background. One of the new trends in evidence-based medicine deals with how to make theory into practice. Applying the practical model from post-SSK to interpret how the notions of evidence-based medicine changed, it is found that evidence-based medicine is an indivisible practical network integrating many natural and social factors as well as material and cultural factors which interconnect through "translation". Therefore, the involvement of various factors such as natural matter, social relations, regional factors, resources of traditional culture and scientific instruments leads up to the ultimate theory becoming the result of multiple factors in a continuous process of seeking the best way in scientific practice. In this motile process, the borderline between nature and society, material and human, natural science and social science vanishes and a new stage called humanistic medicine appears.

[Analysis on the background of arising of Evidence-based medicine].

Science is coming from the background of social culture. Evidence-based medicine (EBM) was generated at the early 90's of 20th Century, and there were some landmark things before its appearance. The background of EBM included: (1) risk control of medical techniques at the 70s of 20th Century; (2) ethical ideas of Protestant, including secularism, rationalism and utilitarianism; (3) British positivism and its tradition.

[Construction and screening of cDNA library of osteosarcoma cells].

OBJECTIVE: To construct a cDNA library of osteosarcoma SAOS-2 cells and screen the proteins interacting with the bone morphogenetic protein-2 (BMP-2) to explore the role of BMP-2 in the development of prostate cancer. METHODS: The total RNA was extracted from SAOS-2 cells, from which poly(A)(+)RNA was purified to generate the cDNA using RT-PCR with primer SMARTIII and primer CDSIIIoligo(dT). The library was constructed and screened by cotransformation of the double-stranded cDNA (dscDNA) and linearized pGADT7-Rec with the bait plasmid to the yeast AH109. The proteins interacting with BMP-2 were screened by AH109 mating with the bait strain Y187, and the interaction was confirmed using far-Western blot analysis. RESULTS: The cDNA library of human osteosarcoma SAOS-2 cells was constructed, which was characterized by high diversity and sufficient capacity. The dscDNA size range was between 250-5000 bp, with a cotransformation efficiency of 4.3 x 10(5) and recombination efficiency of 1.9 x 10(6), and 4.3 x 10(5) clones were screened. The mating efficiency was 32% and 1.0 x 10(6) clones were screened by the bait of BMP-2, and 4 positive clones was obtained and sequenced. CONCLUSION: The diversity and capacity of the cDNA library meet the needs for screening genes related to prostate cancer.