Tortuosity of the superficial femoral artery and its influence on blood flow patterns and risk of atherosclerosis

Biomechanics and Modeling in Mechanobiology - The superficial femoral artery (SFA) is a typical atherosclerosis-prone site. We aimed to explore whether the tortuosity of the SFA associates with the...     

Desulfovibrio vulgaris Hildenborough prefers lactate over hydrogen as electron donor

Desulfovibrio vulgaris can use lactate as an electron donor and accumulate hydrogen. Hydrogen can also be consumed as an electron donor when lactate is depleted or absent. The aim of this study was to determine whether D. vulgaris has an electron donor preference system between lactate and hydrogen and how this system is regulated. In order to be sure that D. vulgaris was grown under the same conditions except for electron donors, continuous growth mode was conducted and the optical density (600 nm) was kept constant. When 20 mmol/l lactate was the sole electron donor, it was depleted after 9 h of incubation while hydrogen was accumulated to 1,500 ppm. After that, the hydrogen level was decreased to and maintained at 400 ppm. When 1,200 ppm hydrogen was provided as the electron donor, the culture reached an OD of 0.2 after 24 h incubation and hydrogen was consumed to 600 ppm. When 1,200 ppm hydrogen and 20 mmol/l lactate were both present, the lactate was consumed during the first 9 h incubation and hydrogen was accumulated to 1,800 ppm. D. vulgaris used hydrogen as an electron donor after the lactate was depleted and the hydrogen level was decreased to 600 ppm. D. vulgaris has both pathways to utilize lactate and hydrogen as electron donors. It prefers lactate over hydrogen and the system is regulated by lactate starvation.     

禽畜养殖粪便中多重抗生素抗性细菌研究

通过对新乡地区8家养猪场和11家养鸡场饲喂抗生素情况的调研,发现头孢氨苄、阿莫西林、卡那霉素、庆大霉素等4种抗生素是该地区被普遍使用的兽药抗生素。通过多点取样法和微生物培养技术对3家养鸡场和3家养猪场不同养殖时期的粪便进行单一抗生素和多重抗生素抗性细菌的检测,结果表明养鸡场堆置1周的粪便中抗头孢氨苄的细菌比例最高,达到65.90%,对所研究的3种和4种抗生素同时抗性的比例高达8.60%—12.51%和9.73%,明显高于饲喂中药的对照养鸡场样本检测结果(0.02%—2.73%和0.12%)。养猪场堆置1周的粪便中检测到抗头孢氨苄的细菌比例也是最高,达到49.12%上,但养猪场粪便中多重抗生素抗性细菌的比例明显低于养鸡场。同时研究发现,在两种养殖场中,幼龄期粪便中检测到的多重抗性细菌比例明显高于成熟期粪便,这可能与养殖过程中鸡、猪在幼龄期由于防病和促生长等因素而同时大剂量使用多种抗生素有关。     

高粱遗传转化研究进展

高粱（Sorghum bicolor）是一种重要的多用途作物, 其遗传转化研究对于高粱的分子育种和分子遗传学基础研究都具有重要意义。该文对高粱遗传转化的方法、标记基因、遗传转化的启动子和受体系统进行了综述, 并提出了今后高粱遗传转化应当集中研究的问题。     

存量规划中大型公共空间更新的公众参与机制研究——以美国东海岸防灾项目为例

面对存量规划背景下城市更新中复杂利益主体,在规划管理过程引入公众参与已逐渐成为中国广泛使用的规划策略。而面对大型的城市公共空间更新,在中国非营利组织体系并未建立完善的现况下,为使自下而上的空间需求与自上而下的规划策略有效对接,以美国纽约东海岸灾后重建计划的实施过程为例,通过比较研究,分析其中公众参与的保障机制,强调顶层法律对建立一套精准、具体的公众参与技术标准的重要性。同时探讨更新规划过程中,公众参与的途径及其中市民阶层的角色参与。讨论政府职能在整体公众参与的保障体系中所具备的多向把控、整体触媒的系统价值。研究为适用于中国国情的、基于公众参与的整体性城市公共空间更新提供新的视角和策略参考。     

Reg3α Overexpression Protects Pancreatic β Cells from Cytokine-Induced Damage and Improves Islet Transplant Outcome

The process of islet transplantation for treating type 1 diabetes has been limited by the high level of graft failure. This may be overcome by locally delivering trophic factors to enhance engraftment. Regenerating islet-derived protein 3α (Reg3α) is a pancreatic secretory protein which functions as an antimicrobial peptide in control of inflammation and cell proliferation. In this study, to investigate whether Reg3α could improve islet engraftment, a marginal mass of syngeneic islets pretransduced with adenoviruses expressing Reg3α or control EGFP were transplanted under the renal capsule of streptozotocin-induced diabetic mice. Mice receiving islets with elevated Reg3α production exhibited significantly lower blood glucose levels (9.057 ± 0.59 mmol/L versus 13.48 ± 0.35 mmol/L, P < 0.05) and improved glucose-stimulated insulin secretion (1.80 ± 0.17 ng/mL versus 1.16 ± 0.16 ng/mL, P < 0.05) compared with the control group. The decline of apoptotic events (0.57% ± 0.15% versus 1.06% ± 0.07%, P < 0.05) and increased β-cell proliferation (0.70% ± 0.10% versus 0.36% ± 0.14%, P < 0.05) were confirmed in islet grafts overexpressing Reg3α by morphometric analysis. Further experiments showed that Reg3α production dramatically protected cultured islets and pancreatic β cells from cytokine-induced apoptosis and the impairment of glucose-stimulated insulin secretion. Moreover, exposure to cytokines led to the activation of MAPKs in pancreatic β cells, which was reversed by Reg3α overexpression in contrast to control group. These results strongly suggest that Reg3α could enhance islet engraftments through its cytoprotective effect and advance the therapeutic efficacy of islet transplantation.     

三叶青叶表型多样性与地上部分总黄酮含量相关性

为揭示不同种源三叶青（Tetrastigma hemsleyanum Diels&Gilg）叶表型多样性变化及其与地上部分总黄酮含量的相关性,以49个三叶青种质资源（简称“资源”）为研究对象,对各资源叶表型的12个长度性状及7个比例性状进行比较,并采用相关性分析、因子分析和聚类分析方法对叶表型性状及其与种源地位置和地上部分总黄酮含量关系进行统计分析。结果表明：各资源叶长度性状存在较大差异,其中,小叶柄和侧生小叶叶片相关性状在三叶青资源鉴别过程中具有较高的参考价值;部分三叶青叶长度性状与比例性状间存在相关性,整体表现为叶柄增长,小叶叶片则更宽阔,而小叶叶片增长,叶片则朝狭长方向发展;中叶长和侧叶柄长等部分叶形性状与种源地纬度、经度或海拔存在显著（P<0.05）或极显著（P<0.01）相关性,可作为种源地地理位置初步判断依据;基于3个叶形公因子的聚类分析结果显示,49个三叶青资源叶形可划分为5个类型,各省（直辖市）三叶青叶类型数量呈以江西为中心,向周围辐射递减的趋势;三叶青地上部分总黄酮含量与种源地地理位置无显著相关性,但与叶片性状公因子（公因子1）呈极显著负相关（P&...