市县级限制开发区环境功能区划研究——以河北省张家口市为例

限制开发地区是我国主体功能区划中划定的提供重要生态功能和农产品的地区,对其进行环境功能区划对于推动环境功能区划制度落地与实施,以及限制开发区的保护与发展有着重要意义。当前国家及省级的环境功能区划研究已经相对成熟,而市县尺度的限制开发地区环境功能区划相关研究较少。在总结现有环境功能区划研究方法的基础上,以河北省张家口市为例,探讨了市县级限制开发地区环境功能区划体系设计和技术方法,提出了以公里格网作为分析单元,结合县域行政边界,基于环境功能综合评价的结果,从自然生态安全、维护人群健康和区域环境支撑能力等3个方面,开展环境功能区划。基于该方法,将张家口市分为自然生态保留区、生态功能保持区、生态功能恢复区、农产品安全保障区、环境开发准入区、聚居发展维护区6类环境功能区,并根据各环境功能区的主要功能及生态环境特点提出相应的发展建议,以期为该区域管理提供可行的操作手段。本文提出的方法也可为其他限制开发地区的环境功能区划提供参考。     

A 10-miRNA risk score-based prediction model for pathological complete response to neoadjuvant chemotherapy in hormone receptor-positive breast cancer

Patients with hormone receptor(HR)-positive tumors breast cancer usually experience a relatively low pathological complete response(p CR) to neoadjuvant chemotherapy(NAC). Here, we derived a 10-micro RNA risk score(10-mi RNA RS)-based model with better performance in the prediction of p CR and validated its relation with the disease-free survival(DFS) in 755 HRpositive breast cancer patients(273, 265, and 217 in the training, internal, and external validation sets, respectively). This model,pres...     

Nitric oxide and changes of iron metabolism in exercise

Accumulated data imply that exercise itself might not lead to a true iron deficiency or 'sport anaemia' in a healthy athlete who has adequate iron intake. The higher prevalence of iron deficiency anaemia in younger female athletes might be not due to exercise itself, but probably results from dietary choices, inadequate iron intake and menstruation. These factors can also induce iron deficiency or anaemia in the general population. However, exercise does affect iron metabolism, leading to low or sub-optimal iron status. The underlying mechanism is unknown. In this review, recent advances in the study of the effect of exercise on iron metabolism and nitric oxide, and the relationship between nitric oxide and iron status in exercise are discussed. A hypothesis that increased production of nitric oxide might contribute to sub-optimal iron status in exercise is proposed.     

The stimulatory effect of ROCK inhibitor on bovine corneal endothelial cells

Reagents which can promote the proliferation, adhesion and migration of cultured corneal endothelial cells (CECs) will be helpful for the treatment of reduced visual acuity due to CECs deficiency. The objectives of this study were to investigate the potential use of an inhibitor of Rho-associated protein kinase (ROCK), Y-27632, to cultured bovine corneal endothelial cells (B-CECs) and evaluated its effects on the proliferation, adhesion and migration of B-CECs. The proliferation of cultured B-CECs was moderately enhanced by 10 μM Y-27632. Y-27632 induced fibroblast-like morphological changes in the cultured B-CECs and normal cell morphology could recover after Y-27632 removal. In addition, Y-27632 was found to significantly enhance the adhesion and migration of B-CECs. Furthermore, the hanging drop aggregation assay showed that Y-27632 promoted B-CECs to form cellular networks and sheets, which proliferated along the liquid–air interface and migrated to the surface of the lid of dish. Our study demonstrated that Y-27632 is a potentially powerful reagent which can enhance the proliferation of cultured B-CECs. Y-27632 will be useful in CEC injection therapy and topical application for CEC deficiency.     

南沙群岛西南部和北部湾口海域鱼类物种多样性

根据2012-2013年在南沙群岛西南部和北部湾口海域春秋两个航次的调查资料, 分析了该海域鱼类种类组成、相对重要性指数和物种多样性等特征。结果表明, 两个航次调查共鉴定鱼类504种, 隶属于2纲31目129科294属; 其中北部湾口海域出现鱼类301种, 南沙群岛西南部海域出现鱼类357种。优势种数量较少, 多以中小型鱼类为主, 且季节间变化较大。春季多样性指数高于秋季, 这主要是因为春季出现的大量鱼类为补充群体, 而许多种类在秋季有向较深海区移动的趋势; 南沙群岛西南部海域多样性指数高于北部湾口海域, 这主要是由于南沙群岛西南部海域受水温和洋流的影响较大造成的。更替指数和迁移指数显示, 秋季鱼类群落结构稳定性要低于春季, 而且两个季节的鱼类群落结构都偏离平衡状态, 主要是由鱼类的洄游和不同适温性鱼类的迁入迁出造成的。综合来看, 南沙群岛西南部海域鱼类物种多样性和群落结构稳定性均高于北部湾口海域, 在努力控制资源可捕量范围的同时, 可合理开发南海中南部海域的渔业资源。     

Generation of virus‐resistant potato plants by RNA genome targeting

CRISPR/Cas systems provide bacteria and archaea with molecular immunity against invading phages and foreign plasmids. The class 2 type VI CRISPR/Cas effector Cas13a is an RNA‐targeting CRISPR effector that provides protection against RNA phages. Here we report the repurposing of CRISPR/Cas13a to protect potato plants from a eukaryotic virus, Potato virus Y (PVY). Transgenic potato lines expressing Cas13a/sgRNA (small guide RNA) constructs showed suppressed PVY accumulation and disease symptoms. The levels of viral resistance correlated with the expression levels of the Cas13a/sgRNA construct in the plants. Our data further demonstrate that appropriately designed sgRNAs can specifically interfere with multiple PVY strains, while having no effect on unrelated viruses such as PVA or Potato virus S. Our findings provide a novel and highly efficient strategy for engineering crops with resistances to viral diseases.     

外源蛋白在大肠杆菌中的表达定位策略

外源基因在大肠杆菌中表达是对基因重组技术的成功应用。外源基因在不同的大肠杆菌表达系统中表达产物可能定位于大肠杆菌空间结构的不同位置:胞质,胞质膜,胞周质,胞外膜和胞外培养基,五种表达定位方式各有其特点和用途 。     

商陆根中抗真菌蛋白的分离和特性研究

从美洲商陆(Phytolacca americana L.)夏天采集的2—4年生宿根中分离了二种抗真菌蛋白,称为PAFP-R_1和PAFP-R_2。分离程序包括用盐溶液提取,经CM-Sephadex离子交换层析、凝胶过滤层析和羟基磷灰石柱层析纯化。在PGA培养基上,0.1mg/ml蛋白明显抑制木霉菌丝的生长;但对细菌的增殖,即使1mg/ml也无抑制作用。用SDS-PAGE测得二者的相对分子量各为13kD和15kD,单多肽链,等电点约为5.8。用酚-硫酸法未测出含糖。二种蛋白均高含半胱氨酸(19mol/mol)。用Edman降解法测得二者的N末端均为Ala。秋天采集的根中,这二种蛋白含量均很低,但富含由二条PAFP-R_1肽链以双硫键联结的二聚体,它无抗真菌活性。冬天宿根中抗真菌蛋白主要成分是Mr为17kD的单肽链蛋白。上述蛋白对于人红血球均无凝集活性,因此不是PWM的成分。以上结果说明,商陆根中有多种具抗真菌活性的蛋白,成分随季节发生变化,它们都是不含糖,高含半胱氨酸,分子量小于20kD的单肽链蛋白。     

The effect of HMGB1 A box on lung injury in mice with acute pancreatitis

The objective of this study is to observe the effect of high-mobility group protein B1 A Box (HMGB1 A) box on lung injury in mice with acute pancreatitis and its effect on the level of high-mobility group protein B1 (HMGB1) in lung, to explore the mechanism. A total of 60 male Institute of Cancer Research mice were randomly divided into control group (n = 30) and treatment group (n = 30). Severe acute pancreatitis mice model was induced by 20% L-Arg intraperitoneal injection. The recombination HMGB1 A box was used in treatment after modeling. All the mice were killed under anesthesia at 24 and 48 h after the modeling injection. The level of HMGB1 and activity of myeloperoxidase (MPO) in lung were measured. The pathological changes of lung were observed. The level of HMGB1 in lung of A box treatment group decreased more significantly 24 h and 48 h after modeling compared with control group. The activity of MPO in lung of A box treatment group decreased more significantly 24 h after modeling compared with control group. The lung tissue pathologic score of A box treatment group decreased more significantly 48 h after modeling compared with control group. HMGB1 expression levels in the lungs were positively related to histological score of injured lung in acute pancreatitis. It indicates that HMGB1 A box is remarkably protective to lung injury induced by acute pancreatitis.     

Screening of the antigen epitopes of basic fibroblast growth factor by phage display

In order to investigate the epitope of basic fibroblast growth factor (bFGF) and its immunogenicity, the epitopes of bFGF were screened from the phage display library with monoclonal antibody GF22, which can neutralize the bio-activity of bFGF. By three rounds of screening, the positive phage clones with bFGF epitopes were selected, which can effectively block the bFGF to bind with GF22. Sequence analysis showed that the epitopes shared a highly conservative sequence (Leu-Pro-Pro/Leu-Gly-His-Phe/Ile-Lys). The sequence of PPGHFK was located at 22-27 of the bFGF. The specific immuno-response of mouse could be highly induced by phage clones with the epitopes. And the anti-bFGF activity induced by LPGHFK was 3 times higher than the original sequence, which showed that the mimetic peptide LPLGHIK might be used as a tumor vaccine in the prevention and treatment of tumor.