光枝勾儿茶内生真菌多样性及抑菌活性研究

为探索贵州苗药光枝勾儿茶内生真菌类群特征、分布部位及其抑菌活性,该研究采用传统方法对贵州省贵阳市和黔西市光枝勾儿茶内生真菌进行分离,并基于分子生物学及统计学对其分类地位进行鉴定及多样性评价,最后通过微量肉汤倍比稀释法筛选具有抑菌活性的菌株。结果表明:(1)从光枝勾儿茶中分离到191 株内生真菌,隶属于3 个门5 个纲10 个目15 个科19 个属,优势属为叶点霉属(Phyllosticta)、间座壳属(Diaporthe)、葡萄座腔菌属(Botryosphaeria)和刺盘孢属(Colletotrichum)。(2)黔西光枝勾儿茶内生真菌香农-维纳多样性指数(H''_Q=2.112)较贵阳(H''_G=1.801)高,索伦森相似性指数Cs_G-Q为0.923,不同组织香农-维纳多样性指数为茎(H''_S=2.004)>根(H''_R=1.764)>叶(H''_L=1.654)>果实(H''_F=1.473),茎和叶内生真菌的索伦森相似性最高(Cs_S-L=0.667)。(3)筛选出的21株内生真菌对供试菌大肠杆菌(Escherichia coli)、金黄色葡萄球菌(Staphylococcus aureus)和沙门氏菌(Salmonella enterica)具有抑菌效果,其中Diaporthe sp. QX4G6对大肠杆菌、金黄色葡萄球菌和沙门氏菌的最小抑菌浓度分别为12.5、6.25、12.5 mg·mL^-1,最小杀菌浓度分别为12.5、6.25、12.5 mg·mL^-1。以上研究结果揭示了光枝勾儿茶蕴藏丰富的内生真菌资源,不同地区及组织内生真菌类群组成有差异,多个分离菌株具有抗菌活性,为光枝勾儿茶内生真菌天然抗菌药物或药源研发奠定了基础。     

Selenium-Alleviated Hepatocyte Necrosis and DNA Damage in Cyclophosphamide-Treated Geese by Mitigating Oxidative Stress

Biological Trace Element Research - Selenium (Se) has been well recognized as an immune-enhancing agent with antioxidant and anti-tumor properties. The commonly used chemotherapy drug,...     

Synthesis and biological evaluation of 9-fluorenone derivatives for SPECT imaging of α7-nicotinic acetylcholine receptor

The α7-nicotinic acetylcholine receptor (α7-nAChR) subtype, is found to have a connection with the pathogenesis of a variety of psychiatric and neurological disorders. Herein, we report the development of radioiodinated 9-fluorenone derivatives as single-photon emission computed tomography (SPECT) imaging tracers for α7-nAChRs. Among the derivatives, the best member of the series 10 (Ki = 2.23 nM) were radiolabeled with ¹²⁵I for in vitro and in vivo studies. The radiotracer [¹²⁵I]10 exhibited robust brain uptake and specifically labeled α7-nAChRs with a peak uptake value of 9.49 ± 0.87%ID/g in brain. Blocking studies demonstrated that the tracer was highly specific toward α7-nAChR. Furthermore, ex vivo autoradiography and micro-SPECT/CT dynamic imaging in mice confirmed the excellent imaging properties. In addition, molecular docking was also performed to rationalize the potency of the chosen compounds towards α7-nAChRs. To conclude, compound 10 could serve as a promising radiotracer for the α7-nAChRs.     

Combined surgical-orthodontic treatment of patients with cleidocranial dysplasia: case report and review of the literature

Objectives

To study the present treatment situation and investigate a better orthodontic approach for patients with cleidocranial dysplasia (CCD) through systematically reviewing the published cases and to conclude the surgical-orthodontic treatment experience of cleidocranial dysplasia.

Methods

A comprehensive search for studies published through to April 10, 2018 was conducted using the Pubmed, Web of Science, and Embase databases. The CCD cases treated with the approach combining surgical exposure and orthodontic treatment were concluded.

Results

Eight papers and 9 finished cases were included to be compared with the present case. The age of cases ranged from 9 to 28?years. Clearing the way of eruption path in early age can facilitate the spontaneous eruption of impacted teeth. For adults, combined surgical-orthodontic treatment can achieve a nearly complete dentition and stable occlusal contact, but it is time consuming and needs surgical assistance. The combination of orthognathic surgery can reduce the difficulty of orthodontic treatment and treatment duration, as well as achieve a better facial profile.

Conclusion

Surgical exposure combined with orthodontic traction is an effective treatment for patient with CCD. Patient’s age, demand, economic circumstances, and status of permanent dentition should be considered when making treatment plan.

     

TIGAR cooperated with glycolysis to inhibit the apoptosis of leukemia cells and associated with poor prognosis in patients with cytogenetically normal acute myeloid leukemia

Background

Cancer cells show increased glycolysis and take advantage of this metabolic pathway to generate ATP. The TP53-induced glycolysis and apoptosis regulator (TIGAR) inhibits aerobic glycolysis and protects tumor cells from intracellular reactive oxygen species (ROS)-associated apoptosis. However, the function of TIGAR in glycolysis and survival of acute myeloid leukemia cells remains unclear.

Methods

We analyzed TIGAR expression in cytogenetically normal (CN-) AML patients and the correlations with clinical and biological parameters. In vivo and in vitro, we tested whether glycolysis may induce TIGAR expression and evaluated the combination effect of glycolysis inhibitor and TIGAR knockdown on human leukemia cell proliferation.

Results

High TIGAR expression was an independent predictor of poor survival and high incidence of relapse in adult patients with CN-AML. TIGAR also showed high expression in multiple human leukemia cell lines and knockdown of TIGAR activated glycolysis through PFKFB3 upregulation in human leukemia cells. Knockdown of TIGAR inhibited the proliferation of human leukemia cells and sensitized leukemia cells to glycolysis inhibitor both in vitro and in vivo. Furthermore, TIGAR knockdown in combination with glycolysis inhibitor 2-DG led leukemia cells to apoptosis. In addition, the p53 activator Nutlin-3α showed a significant combinational effect with TIGAR knockdown in leukemia cells. However, TIGAR expression and its anti-apoptotic effects were uncoupled from overexpression of exogenous p53 in leukemia cells.

Conclusions

TIGAR might be a predictor of poor survival and high incidence of relapse in AML patients, and the combination of TIGAR inhibitors with anti-glycolytic agents may be novel therapies for the future clinical use in AML patients.

     

Flavone-based natural product agents as new lysine-specific demethylase 1 inhibitors exhibiting cytotoxicity against breast cancer cells in vitro

Lysine-specific demethylase 1 (LSD1) has recently emerged as a therapeutic target for cancer. However, almost all LSD1 inhibitors developed to date are chemo-synthesised molecules. In this study, the LSD1 inhibitory activity of 12 natural flavones, including four aglycones and their corresponding monoglycosides and diglucosides, was evaluated. Based on the structure–activity relationships, LSD1 inhibition activity was greater for flavonoid monoglycosides than their aglycones lacking the sugar moiety. The effects of isoquercitrin, which exhibited optimal LSD1 inhibitory activity, on cancer cell properties were evaluated. Isoquercitrin induced the expression of key proteins in the mitochondrial-mediated apoptosis pathway and caused apoptosis in LSD1-overexpressing MDA-MB-231 cells via the inhibition of LSD1. These findings suggest that natural LSD1 inhibitors, and particularly isoquercitrin, are promising for cancer treatment.     

Realizing Ultrafast Oxygen Evolution by Introducing Proton Acceptor into Perovskites

The oxygen evolution reaction (OER) is of prime importance in multiple energy storage devices. Perovskite oxides involving lattice‐oxygen oxidation are generally regarded as highly active OER catalysts, but the deprotonation of surface‐bound intermediates limit the further activity improvement. Here, it is shown that this kinetic limitation can be removed by introducing Sr₃B₂O₆ (SB) which activates a proton‐acceptor functionality to boost OER activity. As a proof‐of‐concept example, an experimental validation is conducted on the extraordinary OER performance of a Sr(Co_0.8Fe_0.2)_0.7B_0.3O_3?δ (SCFB‐0.3) hybrid catalyst, made using Sr_0.8Co_0.8Fe_0.2O_3?δ as active component and SB as a proton acceptor. This smart hybrid exhibits an exceptionally ultrahigh OER activity with an extremely low overpotential of 340 mV in 0.1 m KOH and 240 mV in 1 m KOH required for 10 mA cm^?2 which is the top‐level catalytic activity among metal oxides reported so far, while maintaining excellent durability. The correlation of pH and activity study reveals that this enhanced activity mainly originates from the improved interfacial proton transfer. Such a strategy further demonstrated to be universal, which can be applied to enhance the OER activity of other high covalent oxides with close O 2p‐band centers relative to Fermi energy.     

厦门湾中华白海豚潜在生态廊道识别及人类活动干扰评估

生态廊道具有维持或恢复生态连通性的功能,对于连接生物栖息地、保护物种多样性具有重要意义。现有的生态廊道研究主要集中于陆地,而海洋生态系统具有水体广泛连通、缺乏直观的景观斑块等特点,导致海洋生态廊道的研究成为长期以来的科学难题。以栖息地位于厦门湾的国家一级保护动物中华白海豚(Sousa chinensis)为对象,尝试基于物种分布模型和最小成本路径分析法建立海洋生态廊道的识别方法。研究采用物种分布模型识别厦门湾内中华白海豚的适宜生境分布区和节点,并利用模型产出的生境适宜性结果生成海洋中的阻力表面,模拟计算节点与节点间在阻力表面上的最小成本路径,从而生成物种扩散网络。研究结果显示,厦门湾中华白海豚的分布主要受到航道距离、到岸线距离和叶绿素浓度三项因素的影响,主要适宜生境位于西海域至九龙江口和大嶝海域。潜在的核心生态廊道面积93.19km²,次级生态廊道面积170.41km²,九龙江口-鼓浪屿南侧-黄厝-大小嶝岛沿线可能是厦门湾中华白海豚的主要迁移路线。在此基础上,从用海空间重叠和桥梁影响两方面开展了人类活动对廊道的干扰评估。评估结果显示旅游活动和...     

新时代人才培养需求下工科高校专业课教学创新与实践：以“环境工程微生物学”为例

“环境工程微生物学”是传统工科高校环境类专业的前置核心专业必修课程,为满足新时代下新的人才培养需求,我们教学团队聚焦课程教学中存在的四大痛点问题,通过教学内容、教学方法、评价方式、思政融入四大环节对“环境工程微生物学”课程教学进行教学改革。经多轮成果应用与迭代以及多方教学评价,结果表明该课程的教学改革显著提升了课程的教学质量。