Objective To compare the biomechanical properties between the two-level fixation by im- plantation of pedicle-screws into the adjacent upper and lower vertebrae of the fractured vertebra and the three-level fixation by implantation of pedicle screws into the fractured vertebra and its adjacent upper and lower vertebrae in the treatment of thoracolumbar burst fractures.Methods Eight fresh frozen calf spines were used in this study.Each specimen was tested in four models:intact model as the control,L1 burst fracture model,two-level fixation model, and three-level fixation model.The L1 burst fracture model was created on a biaxial material testing machine (MTS858 Bionix test system,America).During the experiment,the flexion,extension,bilateral bending and axial rotation loadings were applied to the specimens and the range of motion(ROM)was measured with a three-dimensional laser analysis apparatus and the stiffness was calculated subsequently.One-way statistical analysis was used.Results The ROMs under six different loadings in the fracture model became larger obviously(P＜0.05)and the stiffness decreased(P＜0.05).The ROMs in both fixation models were smaller than those in the other models(P＜0.01)and the stiffness increased distinctly(P＜0.05).There were no significant differences in ROMs and stiffness between the two-level fixation and three-level fixation models(P＞0.05).Conclusion Two-level fixation provides similar biomechanical stability as three-level fixation does in the reconstruction of unstable thoracolumbar fractures.

Objective To explore the dosimetry of simplified intensity modulated radiotherapy (sIMRT)in the spinal component of craniospinal irradiation(CSI)compared with conventional plan(3D-CRT).Methods Five previously treated patients were adopted to generate 3D-CRT,3-and 5-field slMRT plans.The prescribed dose was 36 Gy to the planning target volume(PTV)in 20 fractions.The dose distributions of target volume and normal tissues,and homogeneity index(HI)were ananlyzed using the dose volume histogram.The total monitor units(MUs)were also analyzed to compare the delivery time indirectly.Results For 3D-CRT plans,the region of the neighbouring fields only received 70％ of the prescribed dose,and the maximum dose delivered in the normal tissues was increased to approximately 140％ of the prescribed dose.The homogeneity index(HI)of 3-and 5-field sIMRT were 0.09 ± 0.01 and 0.08 ±0.01,respectively,superior to that of 3D-CRT(0.18 ± 0.02,t=7.80,7.65,P＜0.05).The values of V10 for the heart of 3-and 5-field sIMRT were(8.4 ± 1.9)％ and(8.4 ± 2.0)％,respectively,lower than that of 3D-CRT((36.0 ± 6.0)％(t=13.3,13.0,P＜0.05).V20 for the thyroid gland were (12.4±1.5)％ and(12.4±1.6)％,respectively,lower than(69.4±5.7)％ of 3D-CRT(t=26.3,26.4,P＜0.05).V20 for the larynx were(17.2 ± 1.2)％ and(17.9 ± 1.5)％,respectively,lower than that of 3D-CRT[(89.4±7.0)％(t=25.5,26.5,P＜0.05)].V30for the NTwas(4.4±1.4)％,(4.9± 1.9)％,lower than that of 3 D-CRT[(31.9 ± 6.1)％(t=8.5,10.1,P＜0.05)].The averaged values of total MUs for 3-and 5-field sIMRT were 1100 ± 177 and 1160 ±204,respectively,higher than that of 3D-CRT(640 ± 151).Conclusions Compared with the 3D-CRT CSI technique,3-and 5-field sIMRT have better dose distribution and can improve target dose uniformity and protect the organs at risk.

0.05).Conclusion In ensuring the prerequisite of the image quality,using correct scanning technique can appropriately decrease the dose of contrast agents in coronary CTA examination.

Objective To explore the proliferation-promoting effect of bovine mammary gland epithelial cells (BMECs) co-cultured with umbilical cord mesenchymal stem cells (UC-MSCs) in serum-free culture mediuum.Methods Bovine UC-MSCs and BMECs were selected for co-culturing in direct or indirect contact.In the direct contact culture groups, UC-MSCs and BMECs were co-cultured at concentration ratios of 2∶1, 1∶1, 1∶2, 1∶3, 1∶4, 1∶5, and 1:10, respectively.In the indirect contact culture group, the supernatant of UC-MSCs was used as the conditioned medium to re-suspend BMECs.In the control groups, UC-MSCs and BMECs were cultured alone.The cell growth status in each group was observed at 0, 4, 8, 12, 24, 36, 48, 60, 72 h after culture, and cell proliferation was detected by cell counting kit-8 (CCK-8) assay.Results At 48 h, the optical density of the conditioned medium-BMECs group was significantly higher compared with the control groups (P<0.05).Meanwhile, the optical density in the direct contact group at a concentration ratio of 1∶2 reached the peak, which was extremely significantly higher compared with the control groups (P<0.01) and significantly higher compared with the other direct contact culture groups and the conditioned medium-BMECs group (P<0.05).Conclusions Co-culture of UC-MSCs and BMECs in serum-free culture medium is capable to promote the proliferation of BMECs, and the co-culture by cell-to-cell contact has a better effect.The optimal concentration ratio of UC-MSCs to BMECs is 1∶2, and the optimal culture time is 48 h.

Objective To detect the effects and mechanisms of CD147 in thyroid cancer cell SW579. Methods RT-PCR and Western-blot were used to determine the levels of CD147 mRNA and protein in SW579 cells after treated with CD147 specific small interference RNA (siRNA). The proliferative ratio of SW579 cells after treated with CD147 siRNA was detected by CCK-8 assay. We detected the changes of cellular mobility after treated with CD147 siRNA by transwell assay. Mobility related proteins were analyzed by western-blot. Results The proliferative ratio and the mobility of SW579 cells were inhibited significantly by down-regulation of CD147. The levels of MMP-2 and MMP-9 were lower in treated cells than untreated ones. Expression of Wave 2 and a mobility related protein were decreased in accompany with down-regulation of CD147. Conclusion Down-regulation of CD147 inhibits mobility of SW579 by suppressing MMP-2, MMP-9 and WAVE 2.

Acute paraplegia is a rare presentation for a spinal cord ependymoma. Subarachnoid hemorrhage (SAH) due to spinal ependymoma is also very rare. We report a 32-year-old woman who presented with acute paraplegia and typical clinical signs of SAH with normal cerebral angiography, and further diagnostic work-up revealed an spinal cord ependymoma as the source of the hemorrhage. There is evidence that some spinal cord ependymomas have intratumoral hemorrhage, but most of these bleedings occur without symptoms. We discuss the clinical and neuroradiological findings of this rare case and review the literature related to this unusual presentation.431

Bibliometrics ; China ; Pneumoconiosis

Nitrate not only remarkably stimulates the rifamycinbiosynthesis in Amycolatopsis mediterranei, but also influences the primary metabolisms, including the inhibition of fatty acids biosynthesis in the bacterial. This phenomenon has been designated as "Nitrate Stimulating Effect" by the late Prof. J.S. Chiaosince its discovery in the 1970's, and has been found in many other antibiotics-producing actinomycetes subsequently. Based on the research in his laboratory, we have revealed that the nitrate stimulation effect mainly manifests in two aspects over the last two decades. First, nitrate promotes the supply of rifamycin precursors, e.g., UDP-glucose, AHBA, malonyl-CoA and methylmalonyl-CoA. Specifically, the biosynthesis of fatty acids is inhibited by nitrate consequently the acetyl-CoA is shunted into malonyl-CoA. Second, nitrate facilitates the expression of genes in the rifclulsterthat encodes rifamycin biosynthetic enzymes. Following our current understanding, the future research will focus on the signals, the signal transduction pathway and the molecular mechanisms that dictate nitrate-mediated transcriptional and post-translational regulations.
Actinomycetales ; classification ; metabolism ; Acyl Coenzyme A ; chemistry ; Anti-Bacterial Agents ; biosynthesis ; Nitrates ; chemistry ; Rifamycins ; biosynthesis

Objective To investigate the antiviral effects of antisense phosphorothioate oligodeoxynucleotide (ASODN)in 9HTEO infected with influenza A virus (IFAV) in vitro. Methods The ASODN which complemented to genomic PB1, M2, NS, PB2, HA mRNA of IFAV was used to investigate antiviral effection in vitro. The cytopathic effect (CPE) was observed, and the cell survival rates were measured by MTF assay, plaque assay, RT-PCR, Western blot and Immunofluorescence were performed to test anti-viral efficiency of PB1, M2, NS in cells mRNA and protein level. Results 9HTEO cells infected with IFAV almost all died when the multipicity of infection (MOI) is aboved after 5 days cell culture. The ASODN could increase the cell survival rates. The IFAV PB1, M2, NS significantly reduced CPE of IFAV infected 9HTEO cells, reduced the viral replication of IFAV in the cells (P <0.05). Conclusion The ASODN which targeted the mRNA of IFAV gene showed a significant and specific anti-IFAV effect both in mRNA and protein level in cells culture system. The study indicates that the PB1, M2 and NS mRNA may play an important role in regulating IFAV replication, and ASODN may have inhibitory activity on IFAV replication. The results established the basis for further study on new drugs against IFAV infection include the highly pathogenic H5N1 influenza virus.

Objective To evaluate the specificities and sensitivities of neuron-assoeiated(Neu-A) autoantibodies in the diagnosis of neuropsychiatric systemic lupus erythematosus(NPSLE)and explore its role in the pathogenesis of NPSLE.Methods The ncuro-associated autoantibodies including anti-neuroblastoma cell,anti-neuroglioma cell,and anti-brain,anti-spinal antibodies were tested using neuroblastoma cell line SK-N-SH.ueuroglioma cell line U251 or cerebrum and spinal meduHa of mice C57BL/10 as substrates respec tively,Serums of 121 SLE patients fincluding 36 NPSLE patients and 85 systemic lupus erythematosus (SLE)patients without CNS involvement),34 rheumatoid arthritis(RA)patients and 34 healthy controls were tested by indirect immunofluorescence(IIF)assay.Cerebrospinal fluid of 24 NPSLE patients and 22 CNS dis eases controls were also tested.Results The positive rates of anti-neuroblastoma cell antibodies,anti-brain and anti-spinal antibodies in serums of SLE patients were 17.4%,25.6%and 29.8%,respectively.Only 2.9%, 5.9%,0 in 34 RA patients and 0,2.9%,0 in health controls were positive(P＜0.05 or P＜0.01).The specificity of the three antibodies in SLE was 98.5%.95.6%and 100%respectively.Anti-neuroblastoma cell antibodies, anti-brain and anti-spinal antibodies were closely associated with SLEDAI score.The NPSLE patients with positive anti-neuroblastoma cell antibodies,anti-brain or anti-spinal antibodies had frequent seizure atlacks, headache,acute confusion state and mood disorders.There was a higher prevalence of anti-neuroblastoma cell.anti-brain and anti-spinal antibodies in NPSLE than those in SLE patients.29.2%anti-brain and anti- spinal antibodies were detected in the eerebrospinal fluid of NPSLE patients.which were significantly higher than those of disease control group(P＜0.05 or P＜0.01).The specificities of these two antibodies jn NPSLE were 100%and 95.5%respectively.Conclusion Anti-neumhlastoma cell antibody.anti-brain and anti spinal antibodies are valuable markers for the diagnosis of SLE.They are closely associated with the disease activity of SLE and neuropsychiatric symptoms.Anti-spinal antibody may be a sensitive and specific marker for the diagnosis of NPSLE while anti-brain and anti-spinal antibodies in the cerebrospinal fluid are more specifie for the diagnosis of NPSLE.