黄芪改善红细胞变形能力的活性成分研究

膜荚黄芪(Astragalus Membrannaceus(Fisch)Bunge)为豆科紫云英属植物,其根作为传统中药黄芪之正品。本课题通过以改善红细胞变形能力为活性导向筛选,用核孔膜滤筛法,以IF值为指标,对膜荚黄芪的成分进行了系统分离和鉴定。结果表明:黄芪中的黄芪皂甙Ⅱ,Ⅲ,Ⅳ(Astragaloside Ⅱ,Ⅲ,Ⅳ)等皂甙类及芒柄花素(Formononetin),毛蕊异黄酮(Calycosin)等异黄酮类化合物,对孵化红细胞的变形能力有明显的改善作用,这可能是黄芪改善血液流变学指标的重要机理。     

p130/p107 expression distinguishes adipogenic potential in primary myoblasts based on age

Recent investigations have provided significant evidence that many mesodermally derived tissues contain stem cell-like precursors capable of being stimulated to undergo differentiation into a variety of cellular lineages. We have recently reported that primary myoblasts isolated from 23-month-old mice have an increased adipogenic potential when compared to their 8-month-old counterparts. To further characterize the degree of adipocyte differentiation in these myoblasts, we examined early and late markers of adipocyte differentiation. Within the first 24h of adipocyte differentiation, expression of p130 and p107, two members of the retinoblastoma tumor suppressor gene family, are regulated and this event is an important one early in adipogenesis. Consistent with the increased adipogenic potential of the older myoblasts and in contrast to the younger cells, the p130:p107 pattern of expression is very similar to that observed in adipogenesis where there is a transient increase in p107 expression accompanied by a decrease in p130 expression. Interestingly, while these older cells accumulated lipid and expressed genes associated with lipid metabolism, they failed to express adipsin and leptin, two well-established markers of terminal adipocyte differentiation. These results suggest that older myoblasts are capable of initiating and progressing through the adipogenic program to a point where they express genes associated with lipid metabolism, but do not reach a terminally differentiated state. This finding may have important metabolic implications in the aging population.     

基于扎根理论的社区参与国家公园建设与管理的机制研究

大量研究表明自然保护地周边社区居民对保护地的态度是影响社区参与保护,实现保护地管理目标的主要因素,由此建立了"认知-态度-参与"的行为逻辑。中国国家公园体制建设希望进一步推进社区与保护地的关系,全面提升自然保护管理效率,也建立在对这一行为逻辑的认同之上。为验证社区认知与行为的关系,并为促进不同利益相关者参与国家公园建设与管理提供科学支持,研究试图分析武夷山国家公园体制试点区社区居民的国家公园的"认知-态度-参与"的行为逻辑以揭示社区参与国家公园建设与管理的深层机制。与一般研究不同在于,本研究是针对正在建设中的国家公园,使得本地利益相关方的态度有机会影响国家公园建设进程。为获得社区"认知-态度-参与"核心观念,探索社区参与的过程和方式,提出促进社区参与的方法,研究采用扎根理论这一质性研究方法,基于对本地利益相关者采用半结构化开放问题的深度访谈,归纳出概念与范畴,形成社区参与国家公园建设与管理的理论。研究首先形成45个概念与13个范畴,通过范式模型研究发现,稳定资源使用权利、引导社区参与决策、保障社区发展权利、创新社区产业模式、提高个体适应能力、降低政策风险影响等六个主范畴能够解释社区居民对国家公园的认知-态度-参与这一行为逻辑。通过归纳主范畴,研究进一步提炼出社区参与国家公园建设与管理的理论核心在于社区自然资源管理的自主性、创新性与适应性,其内在机制在于社区参与是一个自主性提高的动态过程,需要通过保障社区生计资源禀赋来实现长期的价值转化,最终使其成为社会-生态系统适应性治理的组成部分。在理论阐释基础上,研究提出从改善社区认知、提升社区参与角度推进国家公园建设的路径。研究也指出,所提出的社区参与机制理论能够提炼量化指标评价社区参与,追踪武夷山国家公园体制试点进程。     

健康/根腐病黄连深色有隔内生真菌多样性研究及定殖调查

近几年来黄连根腐病日益严重,对黄连产业造成了较大影响.前期研究表明,黄连根部深色有隔内生真菌(dark septate endophytes,DSE)定殖率与根腐病发生有明显关系,拟对此进行深入探讨.从健康的和患有根腐病的黄连根部分离DSE,通过对ITS序列进行测序和比对进行分子鉴定,比较其分离频率,并对不同产地的黄连...     

A nano-Ni based ultrasensitive nonenzymatic electrochemical sensor for glucose: Enhancing sensitivity through a nanowire array strategy

Highly ordered Ni nanowire arrays (NiNWAs) were synthesized for the first time using a template-directed electropolymerization strategy with a nanopore polycarbonate (PC) membrane template, and their morphological characterization were examined by scanning electron microscopy (SEM) and transmission electron microscope (TEM). A NiNWAs based electrode shows very high electrochemical activity for electrocatalytic oxidation of glucose in alkaline medium, which has been utilized as the basis of the fabrication of a nonenzymatic biosensor for electrochemical detection of glucose. The biosensor can be applied to the quantification of glucose with a linear range covering from 5.0 × 10⁻⁷ to 7.0 × 10⁻³ M, a high sensitivity of 1043 μA mM⁻¹ cm⁻², and a low detection limit of 1 × 10⁻⁷ M. The experiment results also showed that the sensor exhibits good reproducibility and long-term stability, as well as high selectivity with no interference from other oxidable species.     

Rhodobacter sphaeroides和Rhodovulum sulidophilum LHII的α和β亚基的交叉作用关系

类球红细菌(Rhodobacter sphaeroides)和嗜硫小红卵菌(Rhodovulum sulidophilum)为不同属的两种光合细菌,前者的捕光系统II由pucB、pucA基因编码产生的β亚基和α亚基组装形成,后者的捕光系统II由pucsB、pucsA基因编码产生的β亚基和α亚基组装形成.将这两组基因交叉组合,克隆到包含puc启动子的表达载体中,得到两个表达质粒即pRKpucsBpucA和pRKpucBpucsA,然后通过接合转移方法分别转入LHI、LHII和RC缺陷型菌株DD13中,两种接合转移菌株都可以形成捕光系统II并进入光合细菌膜系统.     

Adsorption of Ni2+ and Cu2+ using Bio-Mineral: Adsorption Isotherms and Mechanisms

Heavy metal pollution has become one of the most serious environmental pollution problems. This study aimed to determine the adsorption and desorption characteristics of Ni²⁺ and Cu²⁺ by bio-mineral which was induced by Bacillus subtilis, and to explore the effect of pH on adsorption characteristics. The results showed that the Langmuir model gave a better fit to the experimental data than the Freundlich model, which demonstrated the adsorption was of a single-molecule layer form. The maximum adsorption capacities of the bio-mineral for Ni²⁺ and Cu²⁺ were determined as 67.114 mg/g and 69.930 mg/g, respectively. The desorption rates of Ni²⁺ and Cu²⁺ were very low, especially for Ni²⁺ which was almost 0. Besides, the bio-mineral maintained high adsorption capability for metals ions within a wide pH range (pH ≥ 3). It did not show any new phases after adsorption of Ni²⁺ and Cu²⁺ tested by FTIR, indicating that the bio-mineral and heavy metal ions might mainly physically be adsorbed. The bio-mineral has a larger internal and external specific surface area, pore volume and colloidal properties which are beneficial for the adsorption of metals ions, but shows limits in desorption. This study provides a theoretical basis for the utilization of bio-mineral and opens a new perspective for the remediation of heavy metals pollution.     

Polymorphisms in MX2 Gene Are Related with SCS in Chinese Dairy Cows

Viral infections can play direct or indirect roles in the etiology of the bovine mastitis. Mx dynamin-like GTPase 2 (MX2) gene is a main effector of the antiviral innate immune defense mediated by type I interferon (IFN I), which was demonstrated to confer positive antiviral responses to many viruses. Given the importance of the MX2 in modulating the host immune response, MX2 gene may be a suitable candidate gene for studying disease resistance in dairy cattle. Here, we scanned the sequence variation of the MX2 gene in Chinese indigenous cattle breeds. Twenty-three previously reported SNPs were identified. To further analyze the effects of SNPs detected on mastitis disease, analysis of two SNPs (g.787527 C?>?T and g.787610 T?>?C) from 297 Chinese Holstein cows revealed a significant association with somatic cell score (SCS). Although functional studies are necessary to ascertain whether these two SNPs are causal polymorphisms or merely in linkage with the true causal SNPs, implementation of these two SNPs as genetic markers in the dairy industry may be beneficial in selecting individuals with lower SCS.     

Fasting up‐regulates ferroportin 1 expression via a Ghrelin/GHSR/MAPK signaling pathway

The significant positive correlation between ghrelin and iron and hepcidin levels in the plasma of children with iron deficiency anemia prompted us to hypothesize that ghrelin may affect iron metabolism. Here, we investigated the effects of fasting or ghrelin on the expression of hepcidin, ferroportin 1 (Fpn1), transferrin receptor 1 (TfR1), ferritin light chain (Ft‐L) proteins, and ghrelin, and also hormone secretagogue receptor 1 alpha (GHSR1α) and ghrelin O‐acyltransferase (GOAT) mRNAs in the spleen and/or macrophage. We demonstrated that fasting induces a significant increase in the expression of ghrelin, GHSR1α, GOAT, and hepcidin mRNAs, as well as Ft‐L and Fpn1 but not TfR1 proteins in the spleens of mice in vivo. Similar to the effects of fasting on the spleen, ghrelin induced a significant increase in the expression of Ft‐L and Fpn1 but not TfR1 proteins in macrophages in vitro. In addition, ghrelin was found to induce a significant enhancement in phosphorylation of ERK as well as translocation of pERK from the cytosol to nuclei. Furthermore, the increased pERK and Fpn1 induced by ghrelin was demonstrated to be preventable by pre‐treatment with either GHSR1α antagonist or pERK inhibitor. Our findings support the hypothesis that fasting upregulates Fpn1 expression, probably via a ghrelin/GHSR/MAPK signaling pathway.