The Expression Alteration of BC1 RNA and its Interaction with Eukaryotic Translation Initiation Factor eIF4A Post-Status Epilepticus

Abnormal dendritic sprouting and synaptic remodelling are important pathological features of temporal lobe epilepsy. BC1 RNA is a translation repressor involved in the regulation of the dendritic protein synthesis and mRNA transport, which is essential for dendritic development and plasticity. The expression alteration of BC1 RNA in the pilocarpine induced epilepsy model remains unknown. It is unclear if the interactions between BC1 RNA and eukaryotic initiation factor 4A (eIF4A) exists in this model. The purpose of this study was to investigate the expression changes of BC1 RNA and its interactions with eIF4A post-status epilepticus (SE). Chloride lithium and pilocarpine were used to induce the SE rat model. Either a whole brain or hippocampus tissues were collected at different time points after SE. The expression patterns of BC1 was detected by qPCR and in situ hybridization. The levels of eIF4AI/II protein expression were analyzed via western blotting and immunohistochemistry. The BC1 RNA-eIF4AI/II interaction was determined by electrophoretic mobility shift assay (EMSA). We found that the BC1 RNA levels decreased in hippocampus 3d, 1w and 2w post-SE before the levels recovered. The eIF4AI/II began to rise 3d post-SE and reached the maximum level 1w post-SE. After 1w post-SE the levels decreased in the hippocampal CA1, CA3 and DG subregions. EMSA analysis showed that BC1 RNA specifically interacted with the eIF4AI/II. The BC1 RNA-eIF4AI/II complex reduced to the lowest level 1w post-SE. Our results suggested that BC1 has a negative regulatory correlation with eIF4AI/II, where BC1 RNA could be involved in epileptogenesis by regulating dendritic protein synthesis.     

Large-Area,Low-Cost Infrared Metamaterial Fabrication Via Pulsed Laser Deposition with Metallic Mesh as a Shadow Mask

Metamaterials are artificial periodic structures with negative permittivity and permeability. Several interesting properties can be obtained in metamaterials, such as negative index behavior, which can be used for building perfect lenses, cloaking, antennas, etc. As the metamaterial’s properties are determined by its structure, the key challenge is to reduce the fabrication cost of the periodic structure on the micrometer or nanometer scale for realistic applications. In this paper, we experimentally demonstrate a new one-step method for the fabrication of a large-area infrared metamaterial at extremely low cost. A metallic mesh is used as a shadow mask during the pulsed laser deposition (PLD) process to fabricate a FeNi/SiC/FeNi multilayer sandwich structure on Si substrate (cm² level). The sample shows a strong absorption peak in the infrared frequency range, and the absorption intensity changes with the sample’s geometry.     

Synthesis and biological evaluation of 18F labeled fluoro-oligo-ethoxylated 4-benzylpiperazine derivatives for sigma-1 receptor imaging

We report the synthesis and evaluation of a series of fluoro-oligo-ethoxylated 4-benzylpiperazine derivatives as potential σ₁ receptor ligands. In vitro competition binding assays showed that 1-(1,3-benzodioxol-5-ylmethyl)-4-(4-(2-fluoroethoxy)benzyl)piperazine (6) exhibits low nanomolar affinity for σ₁ receptors (K_i = 1.85 ± 1.59 nM) and high subtype selectivity (σ₂ receptor: K_i = 291 ± 111 nM; K_iσ₂/K_iσ₁ = 157). [¹⁸F]6 was prepared in 30–50% isolated radiochemical yield, with radiochemical purity of >99% by HPLC analysis after purification, via nucleophilic ¹⁸F^? substitution of the corresponding tosylate precursor. The log D_{pH 7.4} value of [¹⁸F]6 was found to be 2.57 ± 0.10, which is within the range expected to give high brain uptake. Biodistribution studies in mice demonstrated relatively high concentration of radiotracers in organs known to contain σ₁ receptors, including the brain, lungs, kidneys, heart, and spleen. Administration of haloperidol 5 min prior to injection of [¹⁸F]6 significantly reduced the concentration of radiotracers in the above-mentioned organs. The accumulation of radiotracers in the bone was quite low suggesting that [¹⁸F]6 is relatively stable to in vivo defluorination. The ex vivo autoradiography in rat brain showed high accumulation of radiotracers in the brain areas known to possess high expression of σ₁ receptors. These findings suggest that [¹⁸F]6 is a suitable radiotracer for imaging σ₁ receptors with PET in vivo.     

Lnc-PFAR facilitates autophagy and exacerbates pancreatic fibrosis by reducing pre-miR-141 maturation in chronic pancreatitis

Chronic pancreatitis (CP) is described as progressive inflammatory fibrosis of pancreas, accompanied with irreversible impaired endocrine and exocrine insufficiency. Pancreatic stellate cells (PSCs) are widely distributed in the stroma of the pancreas and PSCs activation has been shown as one of the leading causes for pancreatic fibrosis. Our previous study has revealed that autophagy is dramatically activated in CP tissues, which facilitates PSCs activation and pancreatic fibrosis. Long non-coding RNAs (LncRNAs) have been recognized as crucial regulators for fibrosis-related diseases. LncRNAs interact with RNA binding protein or construct competitive endogenous RNA (ceRNA) hypothesis which elicited the fibrotic processes. Until now, the effects of lncRNAs on PSCs activation and pancreatic fibrosis have not been clearly explored. In this study, a novel lncRNA named Lnc-PFAR was found highly expressed in mouse and human CP tissues. Our data revealed that Lnc-PFAR facilitates PSCs activation and pancreatic fibrosis via RB1CC1-induced autophagy. Lnc-PFAR reduces miR-141 expression by suppressing pre-miR-141 maturation, which eventually upregulates the RB1CC1 and fibrosis-related indicators expression. Meanwhile, Lnc-PFAR enhanced PSCs activation and pancreatic fibrosis through trigging autophagy. Our study interrogates a novel lncRNA-induced mechanism in promoting the development of pancreatic fibrosis, and Lnc-PFAR is suggested to be a prospective therapeutic target in clinical scenarios.Subject terms: RNAi, Diagnostic markers, Chronic pancreatitis     

Glutathione S-transferase M1 and T1 gene polymorphism and COPD risk in smokers: an updated analysis

We evaluated the association between GSTM1 and GSTT1 gene polymorphisms and susceptibility to chronic obstructive pulmonary disease (COPD) in smokers. A meta-analysis of the published case–control studies was performed. Published literature was retrieved from PubMed, EMBASE, and China National Knowledge Infrastructure (CNKI), with last update in February, 2011. Data were extracted and a fixed- or random-effects model was used to calculate pooled odds ratios with 95% confidence intervals depending on statistical heterogeneity. Fourteen eligible studies, comprising 1,665 COPD cases and 1,614 controls, were included in the meta-analysis. The combined analyses showed that there was a significant difference in GSTM1 genotype distribution between COPD cases and controls among Caucasians, but not among Asians. The combined GSTM1/GSTT1 null genotype conferred a 1.36-fold greater risk for COPD in Asian smokers. The GSTT1 null genotype alone was not associated with enhanced risk for COPD. The GSTM1 null genotype is significantly associated with an increasing susceptibility to COPD in Caucasian smokers, but not in Asian smokers. The GSTM1/GSTT1 null genotype is a significant risk factor for developing COPD in Asian smokers. The GSTT1 null genotype, however, was not associated with COPD.     

鳗鲡幼鱼耳石日轮的研究

本文报道采自辽东半岛沿岸鳗鲡(Anguilla japonica)的白仔鳗和经人工培育的当年幼鳗耳石日轮生长的观察结果。白仔鳗和幼鳗耳石平均直径均与体全长成直线相关。12尾白仔鳗耳石的平均日轮数146.3,据此推测其产卵期为11—12月。观察证实从咸淡水转人到淡水生活的幼鳗耳石的环纹有过渡带存在。     

Synthesis and bioevaluation of N-(arylalkyl)-homospermidine conjugates

N1-(Arylalkyl)homospermidines (1c-1f) and terminally piperazine-substituted homospermidine conjugates (2a-2e) were synthesized and evaluated for cytotoxicity in mouse leukemia L1210, alpha-difluoromethylornithine (DFMO)-treated L1210, melanoma B16, spermidine (SPD)-treated B16, and HeLa cell lines. Results demonstrated that homospermidine was a more effective vector than piperazine-substituted homospermidine in ferrying diverse arenes into cells via the polyamine transporter. The leading compound, 9-anthracenemethyl-homospermidine (1a), was shown to induce apoptosis in B16 cells and IL-3 dependent FL5.12A pro-B cells. The novel conjugate 4-biphenylmethyl-homospermidine (1e) could also induce apoptosis. However, it exhibited different effect on the cell cycle of B16 cells compared to 1a.     

钼,铁,硫化合物激活曝氧的棕色固氮菌固氮酶钼铁蛋白的研究

曝氧后,棕色固氮菌(Azotobacter vinelandii)固氮酶钼铁蛋白的催化活性和圆二色信号都显著降低,而吸收光谱则显著增加。与钼、铁、硫化合物和二硫苏糖醇组成的重组溶液保温后,曝氢蛋白的圆二色信号和吸收光谱几乎完全恢复至天然状态的同时,乙炔还原活性也得到了显著的恢复,表明重组溶液可使曝氧蛋白中的 P-cluster和其它活性部位都得到了不同程度的修复。     

Aberrant Expression of Osteopontin and E-Cadherin Indicates Radiation Resistance and Poor Prognosis for Patients with Cervical Carcinoma

Radiotherapy is the first-line treatment for all stages of cervical cancer, whether it is used for radical or palliative therapy. However, radioresistance of cervical cancer remains a major therapeutic problem. Consequently, we explored if E-cadherin (a marker of epithelial-mesenchymal transition) and osteopontin could predict radioresistance in patients with locally advanced cervical squamous cell carcinoma (LACSCC). Patients were retrospectively reviewed and 111 patients divided into two groups (radiation-resistant and radiation-sensitive groups) according to progression-free survival (PFS). In pretreated paraffin-embedded tissues, we evaluated E-cadherin and osteopontin expression using immunohistochemical staining. The percentage of patients with high osteopontin but low E-cadherin expression in the radiation-resistant group was significantly higher than those in the radiation-sensitive group (p<0.001). These patients also had a lower 5-year PFS rate (p<0.001). Our research suggests that high osteopontin but low E-cadherin expression can be considered as a negative, independent prognostic factor in patients with LACSCC ([Hazard ratios (95% CI) 6.766 (2.940, 15.572)], p<0.001).