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Immunoglobulin A nephropathy (IgAN), the most common primary renal disease, is characterized by abnormal IgA1 deposition. IgAN is caused by NOD-like receptor pyrin domain-containing-3 (NLRP3), which regulates innate immunity. Gubentongluo (GB) decoction, a traditional Chinese medicine, is an effective clinical treatment for IgAN in China. However, little is known about the underlying mechanisms. In this study, IgA1, which is separated from patients with IgAN, together with GB decoction was applied to treat human mesangial cells (HMCs). CCK-8 and the enzyme-linked immunosorbent assay were used to assess cell proliferation and the production of interleukin-1β (IL-1β), respectively. qPCR and Western blot were applied to detect the expression levels of NLRP3, IL-1β, and caspase-1. Our results showed that GB decoction inhibited IgA1-induced cell proliferation and IL-1β production. Furthermore, IgA1-induced upregulation of IL-1β, NLRP3, and caspase-1 was reduced after treatment with GB. Interestingly, MCC950, an NLRP3 inhibitor, showed similar effect as GB decoction. Additionally, NLRP3 overexpression stimulated cell proliferation, IL-1β secretion, and the expressions of IL-1β and caspase-1 in HMCs. But these effects could be alleviated by GB decoction. In conclusion, GB may play a protective role in IgAN cell model by inhibiting NLRP3.

For studying the effects of different addition ways of graphene on the properties of polyaniline/epoxy coatings, the in - situ polymerization method was applied to synthesize polyaniline (PANI)/graphene(G) composite powders on graphene surface, and the as - prepared powders were characterized by X - ray diffractometer, Fourier transform infrared spectrometer and scanning electron microscope. The as - synthesized composite powders, the mixed powders of PANI and G, and the PANI powders were uniformly dispersed in epoxy resin respectively to prepare coatings on the surface of AZ91D magnesium alloy. Subsequently, the effects of different graphene addition methods on the properties of polyaniline/epoxy coatings were studied through electrochemical impedance measurement, water absorption, etc. Results showed that after an immersion within 2 160 h in 3.5% (mass fraction) NaCl solution, the coating added with PANI/G composite powders not only had a higher impedance value in comparision with those added with PANI powders or with PANI/G powders, but also had better flexibility and impact resistance. Compared with the mixed powders of PANI and G, the PANI/G composite powders obtained through in - situ polymerization could better exhibit the shielding effect of G and the corrosion inhibition effect of PANI, and therefore provid better protection to magnesium alloy.

How to realize more reasonable noise addition in location differential privacy-preserving is a hot topic issue.However,adding the same amount of noise in different locations will result in the decrease of service availability and privacy preservation.To this end,a differentially private location privacy-preserving scheme with semantic location is examined in this paper,which can systematically solve the contradiction among privacy-preserving,service availability and time overhead.The proposed method firstly constructs the expected distance by employing the framework of geo-indistinguishability,then determines the sensitivity of different locations by using the privacy quality function and requirement function,and finally adds Laplace noise to different types of region at fine granularity according to the location sensitivity.Comprehensive simulation experiments are carried out on two public datasets,which compare the proposed scheme with the existing methods in terms of query success rate based on Bayesian attack,service availability based on expected distance quantization and time overhead.The experimental results demonstrate that the proposed scheme is feasible and effective,and obtains a better trade-offs among privacy preservation,service availability and time consuming.

Glioma is the most common malignant tumor of the central nervous system, and it isdifficult to cure. The growth of malignant glioma is invasive. In recent decades, the strategy of surgicalresection combined with concurrent radiotherapy and chemotheraphy, and immunocheckpoint inhibitorshave been made progress. However, the therapeutic effect is still not ideal, which may be related to the lowimmunogenicity of tumor cells and the immunosuppression of tumor microenvironment (TME). In the TME,immune cells compete with glioma cells and other proliferating cells for nutrients, while metabolites in theTME affect the differentiation and functions of immune cells. This article summarizes the research progressof glioma metabolism regulation and tumor immunosuppressive microenvironment in recent years, whichprovides new ideas for the study of the mechanism of tumor progression and glioma of treatment. DOI:10.3969/j.issn.1672-6731.2020.02.002

Some primary or secondary diseases of the central nervous system are closely related tohuman immune system. Autoimmune diseases such as multiple Takayasu arteritis (MTA) can causeintracranial vascular lesions. The disorder of autoimmune system can cause limbic encephalitis (LE) andautoimmune hypophysitis (AH). Patients with immunodeficiency disease are prone to opportunisticinfections of the nervous system and malignant lymphoma. At present, the pathogenesis of many immune⁃related diseases in neurosurgery are not clear, and there is a lack of "golden standard" for diagnosis. Someimmune⁃related diseases in neurosurgery, such as human immunodeficiency virus (HIV) encephalopathy andparaneoplastic neurological syndrome (PNS), have low incidence and high clinical misdiagnosis rate. Mostof the immune⁃related diseases in neurosurgery have their own characteristics in terms of pathophysiology,clinical and imaging feature, etc. Understanding these characteristics will be of great help to the diagnosisand differential diagnosis of relevant clinical diseases. This paper intends to briefly describe the commonimmune ⁃ related diseases in neurosurgery, so as to improve clinicians' understanding of immune ⁃ relateddiseases in neurosurgery and even save more patients' lives. DOI：10.3969/j.issn.1672⁃6731.2020.02.010

Glioblastoma is one of the most intractable malignant tumors in human beings. Even if the patients received comprehensive treatment including the maximum surgical resection, postoperative concurrent chemoradiotherapy and sequential chemotherapy, the median survival time of patients was only 14.6 months. In recent years, researchers have found that medium frequency electric field with extremely low⁃intensity can rapidly destroy the dividing tumor cells, and named it as tumor ⁃treating fields (TTF). Clinical trials also showed the TTF can significantly improve the quality of life, prolong progression free survival period and the overall survival of patients with glioblastoma. In the past decade, TTF is the only proven treatment that can prolong the survival period and expected to rewrite the tumor treatment modality. In this article, the basic experiments, theoretical models and clinical trials of TTF will be reviewed. DOI：10.3969/j.issn.1672⁃6731.2019.12.005

Maximize the extent of tumor removal while maximize the preservation of neurological function is the goal of brain tumor surgery. Therefore, brain eloquent functional area mapping of both cortical and subcortical level is the most important procedure during operation. As a new method of noninvasive brain stimulation, transcranial magnetic stimulation (TMS) shows its value in neuroscience. Combining with neuronavigation, navigated transcranial magnetic stimulation (nTMS) can localize functional cortices in both brain tumor patients and healthy volunteers noninvasively and accurately. With the help of neuroanatomical structure and brain functional imaging information fusion, nTMS can localize motor cortex and language related cortex preoperatively and provide reliable connection information of subcortical fiber tracts during surgery. nTMS can also monitor and evaluate function recovery level and brain plasticity patterns post⁃operation, while further improve patients' outcome and quality of life and reduce postoperative complications as well. nTMS shows its significant value applied in brain tumor surgery. DOI：10.3969/j.issn.1672⁃6731.2019.12.004

Malignant glioma, one of the most lethal malignancies, is the most common primary central nervous system tumor with a dismal prognosis. The major obstacle to cure and recurrence is diffuse invasion, which enables glioma cells to escape complete surgical resection and radiotherapy and chemotherapy. Combined with findings in our lab and related articles, this review comprehensively elaborates the therapies target to glioma invasion and migration and relevant molecular mechanisms. DOI：10.3969/j.issn.1672⁃6731.2019.11.004

The complex heterogeneity and therapeutic resistance of malignant glioma may largely account for the poor prognosis of glioma. The incomplete response assessment system of clinical outcomes is an underlying cause for the confounding of true prognostic benefits expected in patients with glioma. The investigation and development of recently introduced agents or radiological measurements caused emergent misunderstandings to the response assessment of glioma. To date, the classical Macdonald's criteria and the Response Assessment of Neuro⁃Oncology (RANO) criteria have been used successively for the evaluation of glioma outcome. However, the Macdonald's criteria only addresses the contrast⁃enhancement component of the tumor, which is only a surrogate to true tumor growth and activity. Ongoing efforts on complementary assessments are necessary to combat malignant glioma. In this review, we highlight the shortcomings of the current criteria and introduce the initiative effort of RANO criteria and its offspring. DOI：10.3969/j.issn.1672⁃6731.2019.11.005

Glioma is the most common primary central nervous system malignancy, which is a fatal and poorly prognostic tumor. Recent years, basic research, clinical diagnosis and treatment as well as various clinical trials related to glioma have been emerged. This article mainly explains the possible changes in the fifth edition of WHO Central Nervous System Tumor Classification and summarizes both the achievements and shortcomings in the development of the glioma diagnosis and treatment standard in China and also elaborates that the Glioblastoma Multiforme Adaptive Global Innovative Learning Environment (GBM AGILE), a new clinical trial system, plays a positive role in the development of the China's precision medical strategy and the pharmaceutical industry driven by scientific and technological innovation. DOI：10.3969/j.issn.1672-6731.2019.11.002

Abstract Examining the coordination of leaf and fine root traits not only aids a better understanding of plant ecological strategies from a whole‐plant perspective, but also helps improve the prediction of belowground properties from aboveground traits. The relationships between leaf and fine root traits have been extensively explored at global and regional scales, but remain unclear at local scales. Here, we measured six pairs of analogous leaf and fine root traits related to resource economy and organ size for coexisting dominant and subordinate vascular plants at three successional stages of temperate forest swamps in Lingfeng National Nature Reserve in the Greater Hinggan Mountains, NE China. Leaf and fine root traits related to resource acquisition (e.g., specific leaf area [SLA], leaf N, leaf P, root water content, and root P) decreased with succession. Overall, we found strong linear relationships between leaf dry matter content (LDMC) and root water content, and between leaf and root C, N, and P concentrations, but only weak correlations were observed between leaf area and root diameter, and between SLA and specific root length (SRL). The strong relationships between LDMC and root water content and between leaf and root C, N, and P held at the early and late stages, but disappeared at the middle stage. Besides, C and P of leaves were significantly correlated with those of roots for woody plants, while strong linkages existed between LDMC and root water content and between leaf N and root N for herbaceous species. These results provided evidence for the existence of strong coordination between leaf and root traits at the local scale. Meanwhile, the leaf–root trait relationships could be modulated by successional stage and growth form, indicating the complexity of coordination of aboveground and belowground traits at the local scale.

DOI: 10.3969/j.issn.1672-6731.2019.05.014

Glioma shows diffuse infiltrative growth in the brain parenchyma. Even following the principle of "maximum safe resection", the residual tumor cells are resistant to adjuvant chemoradiotherapy and continue to invase and migrate in the brain tissue. This is the main reason for the recurrence of glioma and the dissemination in the central nervous system (CNS). As a result, understanding the mode of glioma invasion and migration can provide a new method for the treatment of glioma. This paper reviews our research findings of the invasion and migration of glioma during the period of Twelfth Five-Year Plan for National Economic and Social Development. DOI: 10.3969/j.issn.1672-6731.2018.01.006

Due to the strong pathogenicity of Ralstonia solanacearum, a variety of strategies have been used to develop antibacterial agents; however, antibacterial drugs with targeted effects on R. solanacearum remain lacking. Herein, we present a nanoagent targeting R. solanacearum based on our previous research on poly-(lactic-co-glycolic acid) (PLGA) particles (PLGA-NPs) loaded with methyl caffeate and caffeic acid phenethyl ester. Antibodies that have specific effects on R. solanacearum, which were verified using immuno-PCR, were first used to prepare PLGA-targeted nanoparticles (PLGA-TNPs). The antibody coupling process was investigated in terms of antibody binding degree and antibacterial activity. The EC50 value of PLGA-TNPs was 0.021 mg/mL, which was significantly reduced by 92% in comparison to PLGA-NPs. PLGA-TNPs had a perforating effect on the cell membrane of R. solanacearum, but no effects on Escherichia coli according to the SEM results. In addition, a downregulation of the pathogenicity-related genes compared to PLGA-NP treatment was observed, and the expression of egl, phcA, phcB, pilT, polA-238, and pehC decreased by 78, 79, 87, 61, 58, and 41%, respectively. Therefore, PLGA-targeted nanoparticles not only enhance the activity against R. solanacearum, but also provide a new idea for controlling bacterial wilt.

Objective To explore the value of MRI combined with 18F-fluoro-2-deoxy-D-glucose (18F-FDG) PET and 11C-methionine (11C-MET) PET on differentiating tumefactive demyelinating lesion (TDL) and glioma. Methods Fourteen cases of TDL and 17 cases of glioma were confirmed by pathology directly or internal medicine treatment. MRI was used to observe the lesion boundary, T1WI, T2WI and diffusion - weighted imaging (DWI) signal intensity, enhancement (including ring enhancement and open - ring enhancement, etc.), mass effect, peripheral edema, and the presence of central venectasia, corpus callosum engagement, central necrosis and gray matter engagement. 18F-FDG PET and 11C-MET PET were used to calculate relative uptake values. Results Among all TDL cases, MRI showed that mass effect of 8 cases (8/14) were grade 0, 4 cases (4/14) gradeⅠ, one case (1/14) was gradeⅡ and one case (1/14) gradeⅢ; the peripheral edema of 12 cases (12/14) were gradeⅠand 2 cases (2/14) gradeⅡ. Among all glioma cases, the mass effect of 2 cases (2/17) were grade 0, 6 cases (6/17) gradeⅠ, 7 cases (7/17) gradeⅡand 2 cases (2/17) grade Ⅲ; the peripheral edema of 7 cases (7/17) were grade Ⅰ and 10 cases (10/17) grade Ⅱ. The differences between TDL and glioma were statistically significant (Fisher's exact probability: P = 0.032, 0.024). 18F-FDG PET and 11C-MET PET were not statistically significant in differentiating TDL and glioma (Fisher's exact probability: P = 0.182, 0.081). Conclusions Mass effect and peripheral edema showed in MRI can be used for the differential diagnosis of TDL and glioma. The value of PET-CT in differentiating TDL and glioma is unsure. DOI: 10.3969/j.issn.1672-6731.2017.10.009

DOI：10.3969/j.issn.1672⁃6731.2020.02.001

DOI：10.3969/j.issn.1672⁃6731.2019.12.001

Objective To investigate the feasibility and safety of using navigated transcranial magnetic stimulation (nTMS) to map hand motor cortex and further analyze its clinical application. Methods The first dorsal interosseous (FDI) was selected as target muscle. The location and area of bilateral FDI were mapped by using nTMS in 10 healthy right-handed volunteers. In order to identify the accuracy of nTMS, all individual MRI volumes and the coordinates of hotspots were normalized to Montreal Neurological Institute (MNI) space using SPM8. Positive sites and motor-evoked potential (MEP) were recorded. The areas of hand motor representations were calculated and compared between bilateral cerebral hemispheres. Results nTMS was capable of identifying hand motor cortex area in both hemispheres in all cases. It took 45 to 60 minutes to finish the whole nTMS procedures of each side of hand motor area. The motor cortex was found at the Ω area of bilateral precentral gyri. The right hand motor representation area was significantly larger than that of left area [(6.22 ± 0.76) cm2 vs (4.30 ± 0.40) cm2; t = 7.078, P = 0.000]. Four cases presented sleepiness, but no side effect such as headache or epilepsy was found. Conclusions nTMS is a reliable and safe technique to map hand motor cortex. It can be a very useful supplementary tool for preoperative motor cortex mapping and study on motor functional remodeling. DOI: 10.3969/j.issn.1672-6731.2016.08.011

Objective To investigate whether Rac1 inhibitor has a synergistic effect on temozolomide (TMZ) in inhibiting the proliferation, migration and invasiveness of glioma cells. Methods Human glioma cell lines U87 and U251 were cultured by Rac1 inhibitor, TMZ or Rac1 inhibitor combined with TMZ. They were divided into 4 groups: control group, Rac1 inhibitor group, TMZ group and Rac1 inhibitor + TMZ group. The proliferation, migration and invasiveness of glioma cells were detected by methyl thiazolyl tetrazolium (MTT), migration assay and Transwell assay. Results After cultured by Rac1 inhibitor, TMZ or Rac1 inhibitor + TMZ, the cell proliferation of U87 and U251 were inhibited (P < 0.05, for all). The inhibiting effect of TMZ was stronger than Rac1 inhibitor (P < 0.05, for all), while Rac1 inhibitor + TMZ was much stronger (P < 0.05, for all). U87 and U251 migration [cells/low power field (LPF)] in Rac1 inhibitor group (39.00 ± 9.53, 37.00 ± 5.56), TMZ group (42.00 ± 8.54, 36.00 ± 9.00) and Rac1 inhibitor + TMZ group (18.67 ± 10.54, 14.33 ± 5.00) was lower than that in control group (78.00 ± 11.53, 75.00 ± 4.00), and the differences were significant (U87: P = 0.001, 0.001, 0.000; U251: P = 0.000, for all). U87 and U251 cell invasiveness (cells/LPF) in Rac1 inhibitor group (30.33 ± 3.51, 40.67 ± 4.04), TMZ group (24.00 ± 2.64, 37.33 ± 4.51) and Rac1 inhibtor + TMZ group (11.00 ± 2.00, 15.33 ± 2.52) was lower than that in control group (64.33 ± 4.04, 77.33 ± 3.06), and the differences were significant (U87: P = 0.000, for all; U251: P = 0.000, for all). In paired comparison among different groups, the migration (U87: P = 0.021, 0.011; U251: P = 0.002, 0.003) and invasiveness (U87: P = 0.000, 0.001; U251: P = 0.000, 0.000) of cells in Rac1 inhibitor + TMZ group were significantly decreased than those in other groups. Conclusions Both Rac1 inhibitor and temozolomide can inhibit the proliferation, migration and invasiveness of glioma cells, while Rac1 inhibitor has a significantly synergistic effect on temozolomide. DOI: 10.3969/j.issn.1672-6731.2016.08.009

Background: The radiochemotherapy regimen concomitantly employing temozolomide (TMZ) chemotherapy and radiotherapy (RT) 4 weeks after surgery, followed by 6 cycles of TMZ is a common treatment for glioblastoma (GBM). However, its median overall survival (OS) is only 14.6 months. This study was to explore the effectiveness and safety of early TMZ chemotherapy between surgery and chemoradiotherapy plus the standard concomitant radiochemotherapy regimen. Methods: A randomized, parallel group, open-label study of 99 newly diagnosed GBM patients was conducted at 10 independent Chinese neurosurgical departments from June 2008 to June 2012. Patients were treated with concomitant radiochemotherapy regimen plus early postsurgical temozolomide (early TMZ group) or standard concomitant radiochemotherapy regimen (control group). Overall response was assessed based on objective tumor assessments, administration of corticosteroid and neurological status test. Hematological, biochemical, laboratory, adverse event (AE), and neurological condition were measured for 24 months of follow-up. The primary efficacy endpoint of this study was overall survival (OS). The secondary endpoint was progression free survival (PFS). Results: The median OS time in the early TMZ group was 17.6 months, compared with 13.2 months in the control group (log-rank test P = 0.021). In addition, the OS rate in the early TMZ group was higher at 6, 12, and 18 months than in the control group, respectively (P < 0.05). The median PFS time was 8.7 months in the early TMZ group and 10.4 months in the control group (log-rank test P = 0.695). AEs occurred in 29 (55.8%) and 31(73.8%) patients respectively in early and control groups, including nausea (15.4% vs. 33.3%), vomiting (7.7% vs. 28.6%), fever (7.7% vs. 11.9%), and headache (3.8% vs. 23.8%). Only 30.8% and 33.3% were drug-related, respectively. Conclusions: Addition of TMZ chemotherapy in the early break of the standard concomitant radiochemotherapy regimen was well tolerated and significantly improved the OS of the GBM patients, compared with standard concomitant radiochemotherapy regimen. However, a larger randomized trial is warranted to verify these results.

The hybrid atomistic-continuum coupling method based on domain decomposition serves as an important tool for the micro-fluid simulation. There exists a certain degree of parallelism load imbalance when directly using the USHER algorithm in the domain decomposition–based hybrid atomistic-continuum coupling method. In this article, we propose a grid-based parallel algorithm for particle insertion, named WI-USHER, to improve the efficiency of the particle insertion operation when restricting the size of the region to be inserted or with higher number density. The WI-USHER algorithm slices the region to be inserted into finer grids with proper spacing scale, marks parts of finer grids in black according to three exclusive rules, that is, Single Particle Occupation (SPO), Single Particle Coverage (SPC), and Multi-Particles Coverage (MPC), and finds the target insertion point in the remained white grids. We use two test cases to show the superiority of our WI-USHER algorithm over the USHER algorithm. The WI-USHER algorithm performs lower averaged force evaluation times, which decreases from O ( 10 4 ) to O ( 10 3 ) compared to the USHER algorithm when the number density of slightly high to high value. The percentage of the total parallel simulation time processed by the particle insertion operation decreases from 23.5% to 3% compared to the USHER algorithm.

Different configurations of coupling strategies influence greatly the accuracy and convergence of the simulation results in the hybrid atomistic-continuum method. This study aims to quantitatively investigate this effect and offer the guidance on how to choose the proper configuration of coupling strategies in the hybrid atomistic-continuum method. We first propose a hybrid molecular dynamics- (MD-) continuum solver in LAMMPS and OpenFOAM that exchanges state variables between the atomistic region and the continuum region and evaluate different configurations of coupling strategies using the sudden start Couette flow, aiming to find the preferable configuration that delivers better accuracy and efficiency. The major findings are as follows: (1) the C→A region plays the most important role in the overlap region and the “4-layer-1” combination achieves the best precision with a fixed width of the overlap region; (2) the data exchanging operation only needs a few sampling points closer to the occasions of interactions and decreasing the coupling exchange operations can reduce the computational load with acceptable errors; (3) the nonperiodic boundary force model with a smoothing parameter of 0.1 and a finer parameter of 20 can not only achieve the minimum disturbance near the MD-continuum interface but also keep the simulation precision.

Objective To review preliminary experiences in glioma resection in an integrated operating room equipped with 1.5T intraoperative magnetic resonance imaging (iMRI) and neuronavigation. Methods Clinical data of 49 cases of gliomas located in deep brain or eloquent areas were retrospectively analyzed, focusing on the influence of iMRI and neuronavigation on the surgical strategy, the extent of resection and preservation outcomes of patients' neural function. Results iMRI scan were performed in each case for 1 to 3 times, averaging (1.57 ± 0.68) times. First iMRI of 49 cases revealed that 17 cases of gliomas were completely removed, and 32 cases had different residual tumors, indicating that iMRI frequently affected or modified the surgical strategy of glioma (32/49, 65.31%). Tumors in 9 cases were not completely removed because diffusion tensor imaging (DTI) navigation and intraoperative neurophysiological monitoring found that the lesions were close to the eloquent areas or deep anatomical structures. Twenty three patients with residual tumors underwent further resection guided by iMRI (23/49, 46.94% ). As a result, the complete resection rate of tumors increased from 34.69% (17/49) to 81.63% (40/49). Compared to preoperative situation, follow⁃up study 6 months after the operation found that neural function of 19 cases were improved, and another 30 cases were equal or close to preoperative level without any tumor progression. Conclusion The integration of 1.5T iMRI and neuronavigation helps to maximize the safe removal of the tumors and minimize dysfunction, increasing the accuracy and safety of glioma surgery. DOI：10.3969/j.issn.1672⁃6731.2012.06.008

With the advance of medical imaging, multimodality image fusion emerged to combine the advantages of anatomical imaging including computed tomography (CT), magnetic resonance imaging (MRI), B Ultrasonography (BUS), etc. and functional imaging including functional MRI (fMRI), diffusion tensor imaging (DTI), positron⁃emission tomography (PET), etc., and has made great progress. Accordingly, the neurosurgical concept has changed dramatically. In recent years, functional neuronavigation and intraoperative MRI (iMRI) based on image fusion have made revolutionary progress in neurosurgical procedures, especially for cerebral parenchymal lesions. With the help of multimodal functional neuronavigation, neurosurgeons can intraoperatively mark and protect the brain functional structure. This new technology improves the surgical effect a lot in brain functional areas, reduces postoperative complications, and maximally ensures high quality of life and long survival of patients after operation. DOI：10.3969/j.issn.1672⁃6731.2012.06.004

Objective To provide a more reasonable regimen of temozolomide and thalidomide, and study the mechanism of these 2 drugs in inhibiting the proliferation and growth of U251 glioma cell in vitro. Methods Human glioma cell line U251 was cultured in vitro and divided into different treatment groups for 3 d: temozolomide group (100 μmol/L), thalidomide group (100 μg/L), temozolomide (100 μmol/L) with thalidomide group (100 μg/L) and vehicle control group. After different treatment for 3 d, 3⁃(4, 5⁃ dimethylthiazol⁃2⁃yl)⁃2, 5⁃diphenyltetrazolium bromide (MTT) was adopted for the determination of cell viability, and cell cycle was analysed by flow cytometry. After labeled with acridine orange (AO), autophagy vesicles were quantitatively detected by flow cytometry. TdT⁃ mediated dUTP⁃biotin nick end labeling (TUNEL) was employed in observing and detecting the apoptosis of treated cells. Western blotting was used in examining the autophagy and apoptosis⁃related proteins. Results Compared with the 2 drugs used alone, temozolomide with thalidomide imposed more obvious inhibition on tumor cell growth (P = 0.000, for all). Combination of 2 drugs induced tumor cell cycle arrest in G0-G1. Both of autophagic and apoptotic cell death could be induced by temozolomide with thalidomide in U251. In two⁃drug treatment group, the expression of autophagy⁃related microtubule⁃associated protein 1 light chain 3 (MAP1LC3) and apoptosis⁃related Caspase⁃3 was significantly higher in transcriptional level in comparing with single drug treatment group (P = 0.000, for all). Conclusion Temozolomide combined with thalidomide may induce 2 types of programmed cell death—apoptotic and autophagic cell death by up ⁃regulating the expression of related genes in U251 glioma cell, thereby, the combination of these 2 drugs may suppress the proliferation and growth of U251 glioma cell in vitro. DOI：10.3969/j.issn.1672-6731.2010.05.007

DOI：10.3969/j.issn.1672-6731.2010.05.003

In this report, a series of polycations are designed and synthesized by conjugating reactive oxygen species (ROS)-responsive thioacetal-linkers to low molecular weight (LMW) polyethylenimine (PEI) via ring-opening polymerization. Their structure–activity relationships (SARs) as gene delivery vectors are systematically studied. Although the MWs of the target polymers are only ~9 KDa, they show good DNA binding ability. The formed polyplexes, which are stable toward serum but decomposed under ROS-conditions, have appropriate sizes (180~300 nm) and positive zeta-potentials (+35~50 mV). In vitro experiments reveal that these materials have low cytotoxicity, and higher transfection efficiency (TE) than controls. Furthermore, the title polymers exhibit excellent serum tolerance. With the present of 10% serum, the TE of the polymers even increases up to 10 times higher than 25 KDa PEI and 9 times higher than Lipofectamine 2000. The SAR studies also reveal that electron-withdrawing groups on the aromatic ring in 4a may benefit to balance between the DNA condensation and release for efficient gene transfection.

DOI：10.3969/j.issn.1672-6731.2010.01.013

By solving the full equations of an extended two-fluid model in two dimensions, we give the first numerical study revealing non-equilibrium steady states in sheared entangled polymer mixtures. This research provides answers for some fundamental questions in sheared binary mixtures of entangled polymers. Our results reveal that non-equilibrium steady states with finite domain size do exist, and apparent scaling exponents L ∥ ~ γ · − 1 . 05 and L ⊥ ~ γ · − 1 are found over six decades of shear rate. Since the wall effects get involved in our simulations, the dependence of average domain size on system size cannot be strictly eliminated. In addition, as an obvious influence of viscoelasticity, the polymer viscosity η p appears to induce linear translation of the fitted lines. Through two-dimensional numerical simulations, we show the detailed dynamic evolution of microstructure in binary polymer mixtures with asymmetric composition under shear flow. It is found that the phase patterns are significantly different from symmetric fluids studied previously. Finally, we also identify the importance of wall effects and confirm the irreplaceable role of inertia for a non-equilibrium steady state.

Flow instabilities of non-Newtonian fluids severely hamper the quality of products during various chemical processes, such as fibre spinning, extrusion, and film blowing. The origin of extrusion instability has been studied over many decades. However, no consensus has been reached among the research community so far. In this paper, the possible cause of extrusion instabilities is explored using the finitely extensible nonlinear elastic conformation-dependent (FENE-CD) model with a nonmonotonic constitutive curve. Many well-documented experimental phenomena are reproduced in our simulations, and it could be concluded that the nonmonotonic constitutive curve plays an essential role in extrusion instabilities. In addition, the results imply that the die exit singularity may generate or magnify oscillations.

Free surface flows arise in a variety of engineering applications. To predict the dynamic characteristics of such problems, specific numerical methods are required to accurately capture the shape of free surface. This paper proposed a new method which combined the Arbitrary Lagrangian-Eulerian (ALE) technique with the Finite Volume Method (FVM) to simulate the time-dependent viscoelastic free surface flows. Based on an open source CFD toolbox called OpenFOAM, we designed an ALE-FVM free surface simulation platform. In the meantime, the die-swell flow had been investigated with our proposed platform to make a further analysis of free surface phenomenon. The results validated the correctness and effectiveness of the proposed method for free surface simulation in both Newtonian fluid and viscoelastic fluid.

DOI：10.3969/j.issn.1672⁃6731.2012.06.001