Objective: To investigate the reversal effects of pulsed magnetic fields(PMF) on the drug resistant cell line K562/ADR in vitro and their mechanism.Methods: MTT assay was used to determine the IC50 of ADR on K562/S and K562/ ADR cell lines,the detriment of PMF on the K562/ADR cell line and the reversal effects of the drug resistance after treatment with different frequencies of PMF.Flow cytometry(FCM) was applied to the assessment of concentration of intracellular ADR.Results: The drug-resistance multiple of the K562/ADR cell line was 29.36.PMF did not affect the growth of the K562/ADR cell line.Different frequencies of PMF produced different effects on the IC50 of the K562/ADR cell line.In the same condition,70Hz PMF produced the most significant effect and increasea the concentration of intracellular ADR.Conclusion: PMF can reverse the multidrug resistance of K562/ADR by enhancing the drug concentration in K562/ADR cells,and its frequency is correlated with its reversal effect:low fregucncy produces better effect.

Objective To evaluate the application of 3.0 T magnetic resonance angiography (MRA) in follow-up after embolization of intracranial aneurysms with stent-assisted coils.Methods From June 2013 to June 2015,32 consecutive patients with subarachnoid hemorrhage due to ruptured intracranial aneurysms underwent stent-assisted coil embolization at the Department of Neurosurgery,the Sixth People′s Hospital of Shenzhen were enrolled retrospectively,including 12 males and 20 female,their mean age was 56±10 years.All patients were confirmed to be solitary intracranial aneurysms by digital subtraction angiography (DSA) before embolization.They were followed up with 3.0 T time of flight MRA (TOF-MRA) and contrast enhanced MRA (CE-MRA) at 1 to 2 years after embolization.DSA findings were served as the golden standard.The effect of aneurysm embolization (stabilization,further embolization,recanalization/recurrence) and patency of the parent arteries (without stenosis/mild stenosis,moderate to severe stenosis and occlusion) were compared.Results (1) The comparisons of evaluating the aneurysmal effects and consistencies of DSA among TOF-MRA,CE-MRA and TOF-MRA+source images after stent-assisted coil embolization were poor (Kappa=0.039,P=0.002),medium (Kappa=0.582,P<0.01),and higher (Kappa=0.615,P<0.01),respectively.(2) The comparison of the consistencies in the patency of the parent artery after stent-assisted coil embolization between TOF-MRA,CE-MRA and DSA were poor (Kappa=0.171,P=0.211;Kappa=0.376,P=0.010).(3) With the DSA findings as reference,the accuracy rates of TOF-MRA,TOF-MRA+source images and CE-MRA for interpretation of aneurysm embolization were 37.5% (12/32),75.0% (24/32),and 71.9% (23/32),respectively.TOF-MRA compared with TOF-MRA+source images and CE-MRA respectively,there were significant differences in the accuracy rates (χ2=9.04,P=0.003;χ2=7.63,P=0.006);there were no significant differences in the accuracy rates between TOF-MRA+source images and CE-MRA (χ2=0.08,P=0.777).(4) With the DSA findings as reference,the accuracy rates of TOF-MRA and CE-MRA for interpretation of the patency of the parent artery were 37.5% (12/32) and 62.5% (20/32) respectively.There was no significant difference in the accuracy rate (χ2=4.67,P=0.097).Conclusions The accuracy rate of 3.0 T CE-MRA for evaluating the embolization effect of intracranial aneurysms after stent-assisted coil embolization was superior to that of TOF-MRA.It can be used as a preferred non-invasive examination during the follow-up.TOF-MRA+source images are equivalent to CE-MRA,however,TOF-MRA and CE-MRA for the evaluation of the accuracy of patency of the parent arteries are low.For positive or indeterminate results of MRA examinations,the individualized analysis should be performed,if necessary,perform DSA examination.

0.05). Conclude:The bone type may affect the stability of ITI osseointegrated implants.

On the basis of the well-established principles and techniques about flow chamber, we have designed and made a kind of parallel plate system to apply steady fluid shear stress to osteoclast-like cells etc. in vitro. Biocompatible rubber and metal clamping apparatus made of aluminium alloy are used to seal the flow chamber without changing its even height designed beforehand. The influence of hydrostatic pressure on cells is minimized by adjusting the glass slide and the fluid surface in the upper reservoir to the same horizontal plane. This system can be used to investigate the responses of osteoclast-like cells etc. to fluid shear force in terms of morphology, physiology or biochemistry.
Biomechanical Phenomena ; Cell Culture Techniques ; instrumentation ; Humans ; Osteoclasts ; cytology ; Pulsatile Flow ; Stress, Mechanical

The progressive encephalopathy with edema,hypsarrhythmia,and optic atrophy (PEHO) syndrome is a unique pediatric neurodevelopmental disorder,characterized by a combination of severe mental retardation,early onset epileptic seizures,pedal edema,optic/cerebellar atrophy,and early death.The affected individuals have neither optic atrophy nor the typical neuroradiological findings has been described as PEHO-like syndrome.At present,there are few reports about PEHO syndrome in China.In this study,we summarizes the incidence,etiology,clinical manifestations,and related genes of PEHO syndrome,and aims to provide assistance for future clinical work.

Objective To study the relationship between hypertensive cerebral hemorrhage and microbleeds by analyzing the characteristics of magetic susceptibility-weighted imaging.Methods Fifty-one patients with mild hypertensive cerebral hemorrhage admitted to Shenzhen Nanshan District No.6 People's Hospital for MRI (T1WI,T2WI and T2FLAIR),susceptibility-weighted imaging,and magnetic resonance angiography from June 2016 to June 2017 were included in this study.Their MRI data were analyzed.Results Multiple foci of microbleeds and small vessel hyperplasia were detected in hemorrhage regions of the 51 patients included in this study,including ＞2 foci of microbleeds in intracranial basal area,thalamus,brain stem and cerebellar area of 40 patients (78.4％),and cerebral small vessel hyperplasia and VR space enlargement in 11 patients (21.6 ％).Magnetic resonance angiography showed cerebral middle artery and basal artery atheroclerosis in 15 patients but no vascular dissection,stenosis,aneurysm and vascular malformation in the other patients.Conclusion MRI can show the pathological changes in cerebral blood vessels of hypertensive hemorrhage patients,including cerebral microbleeds,cerebral small vessel hyperplasia and VR space enlargement.

Objective:To assess the efficacy and toxicity of chemoradiotherapy in the treatment of early stage extranodal nasal-type NK/T-cell lymphoma (ENKTCL).Methods:Retrospective review was conducted for 174 patients with pathological proved early stage ENKTCL who were treated in the Department of Radiation Oncology, Peking University Cancer Hospital & Institute. The Kaplan-Meier survival analysis was adopted to calculate the local-regional control (LRC), overall survival (OS), and progression free survival (PFS), and the Log-rank test COX regression model were applied to univariate and multivariate analyses.Results:The patients in this study included 102 and 72 patients diagnosed with Ann Arbor stage-Ⅰ and stage-Ⅱ, respectively. Among them, two patients received radiotherapy alone and 172 patients were treated with combined chemoradiotherapy. The overall response rate of all the patients was 94.2%, with a complete response (CR) rate of 87.9% (153). Furthermore, the rates of 5-year OS, PFS, and LRC were 87.3%, 83.1%, and 91.9%, respectively. The most common toxicities during the chemotherapy and radiotherapy included myelosuppression and oral mucositis, with grade ≥ 3 myelosuppression and grade ≥ 3 oral mucositis accounting for 62.1% and 10.9% of all patients, respectively. As shown by multivariate analysis, the adverse prognostic factors for OS included age > 60, B symptoms, and stage Ⅱ, while the adverse prognostic factors for PFS included age > 60 and stage Ⅱ. Meanwhile, the PFS rate was significantly improved by increasing the radiation dose (≥ 50 Gy vs.<50 Gy), and the 5-year PFS rates of the two groups were 83.5% and 76.5%, respectively [hazard ratio ( HR) 0.374; 95% CI, 0.169-0.826; P=0.015]. Conclusions:A good therapeutic effect can be achieved for early stage NK/T-cell lymphoma and the toxicities after combined chemoradiotherapy can be tolerated.