BACKGROUND:Improper angle of prosthesis placement often induces acetabular cup impact, and limits the scope of activity of artificial hip joint, and cannot meet the requirement of daily life. At present, the angle of acetabular cup instal ation remains controversial during total hip arthroplasty. Moreover, there is lack of targeted guide for the acetabular cup instal ation during hip arthroplasty with different head-neck ratios. OBJECTIVE:To explore the safe range of the artificial acetabular cup instal ation angle for different head-neck ratios. METHODS:In accordance with the calculation formula of range of internal rotation and external rotation, abduction and adduction, flexion and extension after total hip replacement, interpretation of dynamical variety law of acetabular abduction and anteversion, and deriving inequalities depending on Widmer’s standard of artificial hip joint normal activities range:(1) external rotation range was at least 40°, and internal rotation range was at least 80°. (2) Abduction range was at least 50°, and adduction range was at least 50°. (3) Anteflexion range was at least 130°, and extension range was at least 40°. The safety scope of artificial hip joint instal ation angle at different head-neck ratios was determined by solving the above three groups of inequality. RESULTS AND CONCLUSION:The safe range of the artificial acetabular cup instal ation angle for different head-neck ratios was different. To meet the normal hip joint activities, the head-neck ratios of artificial hip should be greater than 22/12. Artificial hip joint activities gradual y increase with the enlargement of head neck ratios. With enlarging the head-neck ratios, the acetabular cup instal ation safety angle scope of abduction and anteversin gradual y increases and the extreme of abduction increases gradual y, then with anteversion increasing gradual y, the abduction upper extreme of the security scope gradual y decrease and lower extreme of the security scope gradual y increase, tending to 45° symmetrical y. When anteversion is the biggest, the abduction should be 45°.

BACKGROUND:The cervical pedicle screws provide ideal three-column stability for cervical vertebra, but there is stil no a standard with the choice of pedicle screw place methods in cervical vertebra. Here, we try to seek a simpler, safer and accurate pedicle screw place method.OBJECTIVE:To evaluate the accuracy and security of transpedicular screw placement assisted by rapid prototyping individual navigation template. METHODS:Eight cadaver cervical specimens (C3-6) were selected to take CT-scan and data were saved in DICOM format. Three-dimensional (3D) software MIMICS was used to establish the C3~6 3D model, and designed the best pedicle screw channel. According to the morphological feature of the posterior cervical spine elements, the reverse template was designed. Then, the best pedicle screw channels were fused into bilateral navigation template. The navigation template was manufactured by rapid prototyping, and saved in STL format. Rapid prototyping technology was used to print out the navigation template. Cervical pedicle screws were inserted with the assistance of navigation templates fitted with the posterior structure of the vertebral body. Postoperative X-ray and CT scan were used to evaluate the accuracy of screw placement. RESULTS AND CONCLUSION:(1) Total y 64 screws were inserted with the assistance of individual navigation templates. Of them, 62 screws were completely in the pedicle;1 screw perforated the medial cortex of pedicle;1 screw perforated the lateral cortex of pedicle. Accuracy of screw placement was 97%. (2) The individual navigation template with a high accuracy rate is a feasible and safe method for cervical pedicle screw placement, which has great prospects for clinical application.

can specifically combined with EGFR, which may be applied to noninvasive NIRF imaging of tumors highly expressed EGFR in vivo.

Objective To compare the clinical value of cardiac magnetic resonance (CMR)and echocardiography in diagnosis of hypertrophic cardiomyopathy (HCM).Methods 3 6 patients with HCM diagnosed clinically underwent CMR examination,and then compared with the results of echocardiography.Results 36 cases of HCM were all detected by CMR,including 15 cases of ventricular-septal HCM,5 cases of diffuse HCM,4 cases of midventricular HCM,2 cases of anterior-wall HCM and 10 cases of apical HCM.In addition,12 cases were performed enhanced-CMR scanning,and myocardial ischemia was showed in 4 cases and myocardial fibrosis in 5 cases.1 3 cases of ventricular-septal HCM,5 cases of diffuse HCM,3 cases of midventricular HCM and 1 cases of anterior-wall HCM were detected by echocardiography respectively(22/26).There was no significant difference between echocardiography and CMR(26/26)(P＞0.05).However, only 3 cases of apical HCM were detected by echocardiography (3/10)definitlely,and there was statistically significant difference between echocardiography and CMR(10/10)(P＜0.05).Additionally,on CMR theleft ventricular ejection fraction(EF)in all patients [(58.24±3.24)%] was significantly lower than the results of echocardiography [(71.20±6.24)%]and the left ventricular mass (LVM)[(126.54±36.42)g/m2 ]was higher than echocardiography [(84.54±36.42)g/m2 ],and the mean EF and LVM value had a significant difference between echocardiography and CMR (P＜0.05).Conclusion CMR imaging is superior to echocardiography in the diagnosis of HCM and evaluation of cardiac function,especially in the apical HCM.In addition,myocardial perfusion and delayed-enhanced imaging can effectively assess myocardial perfusion and viability in HCM.

Objective To investigate the safety and effect of zoning laminectomy for the ossification of thoracic ligamentum flavum.Methods From November 2011 to December 2014,34 patients (15 males,19 females;41-76 years old,average 55.0±8.1) with ossification of thoracic ligamentum flavum (OLF) were treated by zoning laminectomy.The course of disease ranged from 1 month to 123 months (average 16.5 months).According to the anatomical characteristics and the pathological ossification process of the thoracic ligamentum flavum,we proposed the concept of "zoning",which divided each segmental thoracic OLF into three zones:"safety zone","middle zone" and "risk zone".From the features of anatomy of LF and process of OLF development,we found there is no or less cerebrospinal fluid between spinal cord and the tip of each ossified nodular masses in severe OLF,any procedures using instruments in this area have the potential to cause irreversible spinal cord injury,we defined this area as "risk zone",the "null" area of each lamina and lateral and dorsal side of nodular masses as "safety zone",and the other area as "middle zone".From "safety zone" to "risk zone" the spinal canal decreased gradually,different zone needs different surgical strategy:This surgical procedure first removed the "null" area of superior and inferior lamina and dorsal side of each segmental OLF.Next,partially or totally resected the "middle zone",exploring the lateral side of nodular masses,and the "risk zone" was exposed and isolated.Finally,dissected the lateral side of nodular masses,and then the "risk zone" was floated and resected with a directly decompressing the spinal cord.Preoperative and postoperative modified Japanese Orthopedic Association (JOA) score and neurologic functional recovery ratio were used to evaluate the surgical outcomes.Results Of the total 83 decompressed OLF segments,5 (6.0％) located in the upper thoracic spine (T1-T4),8 (9.6％) in the midthoracic spine (T5-T8),and 70 (84.4％) in the lower thoracic spine (Tg-L 1).The followed up ranged from 4 to 40 months,with an average of 21.7±9.9 months.The mean JOA score increased significant from 5.3±2.0 preoperatively to 8.8±1.8 at the final follow-up (t=1 1.566,P=0.001).Postoperative average JOA neurologic functional recovery rates were 63.2％±24.7％,including excellent in 15 cases,good in 11 cases and fair in 8 cases.The excellent and good rate was 76.5％.Twelve cases had transient CSF leakage because of dural defect.The dural defect was only treated by tightly suturing the paraspinal muscles,the subcutaneous tissue,and the skin layers.The CSF leakage lasted for 6 to 8 days after operation.Two cases with wound infection were treated with debridement and antibiotics and healed completely.One case with thoracic spinal cord transient incomplete paralysis due to a post-operative epidural hematoma was treated with an emergency operation and got recovered neurological function.Conclusion Zoning laminectomy has the advantages of safe manipulation and thorough decompression,which is an effective choice for the surgical treatment of thoracic OLF.

Objective To study the value of new 16S rRNA gene chip in pathogen detection of neonatal sepsis.Method Newborns with suspected sepsis hospitalized in Peking University Shenzhen Hospital from January 2015 to December 2017 were chosen as the subjects.Blood culture and gene chip were both used to detect the pathogens of these infants.The positive rate,the detection time,and the blood volume needed for detection were compared between the two methods.Result A total of 306 cases of suspected neonatal sepsis were included in the study.Among them,34 (11.1％) were positive for blood culture and 54 (17.6％) were positive for gene chip.98 cases were diagnosed as neonatal sepsis,34 (34.7％) were positive for blood culture,and 52 (53.1％) were positive for gene chip.The positive rate of gene chip was higher than that of blood culture (P ＜ 0.05).For the 5 common pathogens of neonatal sepsis,the positive rate of gene chip was higher than that of blood culture.Time to positivity (TTP) and pathogen identification time of blood culture were (14.6 ± 5.5) h and (72.9 ± 19.0) h,respectively.TTP and pathogen identification time of gene chip were both 3 h.The detection time of gene chip was significantly less than that of blood culture (P ＜ 0.001).The blood volume needed for detection of blood culture and gene chip was 1 ～ 2 ml and 0.5 ml.Gene chip needs less blood volume than blood culture.Conclusion Compared with the traditional blood culture,gene chip can quickly detect the pathogens in the blood with higher positive rate and less blood volume.Gene chip is of great value in the diagnosis of neonatal sepsis.

Objective To observe the effect of novel tissue engineered nerve grafts, which combined silk fi-broin/collagen scaffold with a co-culture of Schwann cells(SCs)and adipose-derived stem cells(ADSCs), to repair rat sciatic nerve defects. Methods From February, 2015 to August, 2016, the culture and purify SCs and ADSCs were isolated. And co-cultured at a ratio of 2∶1 and introduced into a silk fibroin (SF)/collagen scaffold to construct a tissue-engineered nerve conduit (TENC), which were transplanted to bridge 10 mm long sciatic nerve defects in rats. The experiment was divided randomly into 4 groups (10 rats/group): those bridged with plain SF/collagen scaffolds (Scaffold group), those bridged with TENCs (TENC group), those bridged with autografts (Autograft group) and those unoperated side (Normal group). The mechanical properties were examined using a universal testing machine(Instron 5865). Scanning electron microscopy was performed to observe the structure of the SF/collagen scaffold and the cells' growth. A series of electrophysiological examinations and morphological analyses were performed 12 weeks after surgery to evaluate the effect of the TENC on peripheral nerve regeneration.And One-way ANOVA was used to ana-lyze the data. If the differences between groups were statistically significant, the Turkey's method was further applied for comparison. Results The plain SF/collagen scaffold showed appropriate pore size and good intercommunicating of holes. The cells were tightly attached to and partly coiled about the scaffold and exhibited either a spindle or a spherical shape. The results of the mechanical measurement revealed that the maximum and average Young’s moduli of the SF/collagen scaffold were (10.80 ± 0.30) MPa and (8.14 ± 0.20) MPa, respectively. The mechanical properties ensure that the scaffold could resist muscular contraction and maintain its shape unchanged for a considerable period of time after grafting.All rats in each group had achieved nerve defect regeneration in varying degrees.But in terms of the effect of the repaired nerve, those treated with TENC were similar to those with autologous nerve grafts but superior to those with plain SF/collagen scaffolds. Conclusion The TENC that combined silk fibroin/collagen scaffold with a co-culture of SCs and ADSCs had normal nerve-like structure, and can bridge sciatic nerve defect and promote nerve growth.

Since the utilization of anthracyclines in cancer therapy, severe cardiotoxicity has become a major obstacle. The major challenge in treating cancer patients with anthracyclines is minimizing cardiotoxicity without compromising antitumor efficacy. Herein, histone deacetylase SIRT6 expression was reduced in plasma of patients treated with anthracyclines-based chemotherapy regimens. Furthermore, overexpression of SIRT6 alleviated doxorubicin-induced cytotoxicity in cardiomyocytes, and potentiated cytotoxicity of doxorubicin in multiple cancer cell lines. Moreover, SIRT6 overexpression ameliorated doxorubicin-induced cardiotoxicity and potentiated antitumor efficacy of doxorubicin in mice, suggesting that SIRT6 overexpression could be an adjunctive therapeutic strategy during doxorubicin treatment. Mechanistically, doxorubicin-impaired mitochondria led to decreased mitochondrial respiration and ATP production. And SIRT6 enhanced mitochondrial biogenesis and mitophagy by deacetylating and inhibiting Sgk1. Thus, SIRT6 overexpression coordinated metabolic remodeling from glycolysis to mitochondrial respiration during doxorubicin treatment, which was more conducive to cardiomyocyte metabolism, thus protecting cardiomyocytes but not cancer cells against doxorubicin-induced energy deficiency. In addition, ellagic acid, a natural compound that activates SIRT6, alleviated doxorubicin-induced cardiotoxicity and enhanced doxorubicin-mediated tumor regression in tumor-bearing mice. These findings provide a preclinical rationale for preventing cardiotoxicity by activating SIRT6 in cancer patients undergoing chemotherapy, but also advancing the understanding of the crucial role of SIRT6 in mitochondrial homeostasis.