Establishing non-human primate models of human diseases is an efficient way to narrow the large gap between basic studies and translational medicine. Multifold advantages such as simplicity of breeding, low cost of fe...Establishing non-human primate models of human diseases is an efficient way to narrow the large gap between basic studies and translational medicine. Multifold advantages such as simplicity of breeding, low cost of feeding and facility of operating make the tree shrew an ideal non-human primate model proxy. Additional features like vulnerability to stress and spontaneous diabetic characteristics also indicate that the tree shrew could be a potential new animal model of human diseases. However, basal physiological indexes of tree shrew, especially those related to human disease, have not been systematically reported. Accordingly, we established important basal physiological indexes of domesticated tree shrews including several factors: (1) body weight, (2) core body temperature and rhythm, (3) diet metabolism, (4) locomotor rhythm, (5) electroencephalogram, (6) glycometabolism and (7) serum and urinary hormone level and urinary cortisol rhythm. We compared the physiological parameters of domesticated tree shrew with that of rats and macaques. Results showed that (a) the core body temperature of the tree shrew was 39.59±0.05 °C, which was higher than that of rats and macaques; (b) Compared with wild tree shrews, with two activity peaks, domesticated tree shrews had only one activity peak from 17:30 to 19:30; (c) Compared with rats, tree shrews had poor carbohydrate metabolism ability; and (d) Urinary cortisol rhythm indicated there were two peaks at 8:00 and 17:00 in domesticated tree shrews, which matched activity peaks in wild tree shrews. These results provided basal physiological indexes for domesticated tree shrews and laid an important foundation for diabetes and stress-related disease models established on tree shrews.展开更多
Oxidative status assessment is an initial step in tumor related studies. To the best of our knowledge, this is the first study considering oxidative activity of both serum and tissue specimens in human basal cell carc...Oxidative status assessment is an initial step in tumor related studies. To the best of our knowledge, this is the first study considering oxidative activity of both serum and tissue specimens in human basal cell carcinoma (BCC), which is the most common tumor in the world. Concentration of Malondialdehide (MDA) in human basal cell carcinoma (BCC) and individually matched normal skin tissue were examined with spectrophotometery method. Fresh normal and cancerous skin paired tissue was obtained from 60 patients who underwent curative BCC resection at one center in Tehran (Razi hospital). Serum Concentration of Malondialdehide (MDA) in these patients and 55 normal subjects were also measured. MDA level in cancerous tissue of patients with skin BCC (1.0 ± 0.14 ng/g) was significantly (p = 0.001) higher than normal neighboring skin tissue (0.3 ± 0.07 ng/g). A remarkable (Not significant, P = 0.18) increase was found in the serum MDA level in patients with skin BCC (8.0 ± 2.3 ng/ml) in comparison with the control subjects (7.3 ± 2.9 ng/ml). A significant positive correlation (r = 0.276, p = 0.03) was found between Serum MDA and skin tissue MDA for non-affected skin tissue (normal neighboring skin), whereas no significant correlation (p > 0.05) was found for cancerous tissue. Cut-point of 5.2 ng/ml of serum MDA concentration showed a screening sensitivity of 95%. There is an active oxidative process in BCC lesions. Serum MDA concentration can be used either as a screening test or a predictor for tissue MDA concentration.展开更多
Drought stress strongly affects soil biota and impairs crop production, which under climate change will be exacerbated in semi-arid cropping regions such as the Sahel. Hence soil management systems are needed that can...Drought stress strongly affects soil biota and impairs crop production, which under climate change will be exacerbated in semi-arid cropping regions such as the Sahel. Hence soil management systems are needed that can buffer against drought. In West Africa, field studies have found intercropping of millet with the native shrub Piliostigma reticulatum improves soil-plant-water relations, microbial activity and diversity, and suppress parasitic nematodes, which can significantly increase crop yield. However, little information is available on its beneficial or negative effects on soils or crops during water stress. Therefore, the objective was to investigate the impact of P. reticulatum in moderating water stress effects on soil properties and pearl millet (Pennisetum glaucum [L.] R. Br.) productivity. In the greenhouse, soil chemical and microbial properties and millet growth were investigated with a factorial experiment of varying levels of soil moisture (favorable, moderately stressed, or severely stressed water conditions) that was imposed for 55 days on soils containing sole P. reticulatum or millet, or millet + P. reticulatum. The results showed that the presence of P. reticulatum did not buffer soils against water stress in relation to soil chemical and microbial properties measured at the end of the experiment. Severe water stress did significantly decrease the height, number of leaves, and aboveground biomass of millet plants. Additionally, respiration, nematofauna trophic structure and abundance decreased as water stress increased. Lastly, bacterial feeders and plant parasitic nematodes were the most sensitive to severe water stress while fungal feeding nematodes remained unaffected. The results suggested that the intensity of water stress had more negative effects on soil basal respiration rather than soil microbial biomass.展开更多
设计一种采用基底应力附加固结法的层状砂土桩基混凝土施工技术,进行层状砂土桩基混凝土动力夯实数值分析,以此为指导进行地基夯实处理,提高基底应力的固结性能,通过对层状砂土基桩混凝土最大荷载作用点产生沉降应力分析,得到层状砂土...设计一种采用基底应力附加固结法的层状砂土桩基混凝土施工技术,进行层状砂土桩基混凝土动力夯实数值分析,以此为指导进行地基夯实处理,提高基底应力的固结性能,通过对层状砂土基桩混凝土最大荷载作用点产生沉降应力分析,得到层状砂土基桩混凝土最大荷载作用点的应力响应结果,设计出基地应力固结法的砂土基桩混凝土施工技术和试验方案。结果表明,该施工技术能使基底应力消散时间延长,有效满足基底的排水固结处理时间,使得各层土的水平位移基本维持在50 mm以内,避免了水平位移和基桩沉降。承压能力测试显示,地基承载力特征值可达160 k Pa,满足设计要求的120 k Pa,提高承压能力,有效避免了基底最大荷载作用点产生沉降,提高建筑安全性能。展开更多
基金supported by grants from the Chinese Academy of Sciences (KSCX2-EW-R-12, KSCX2-EW-J-23)the National Natural Science Foundation of China (81171294)Shanghai Science & Technology Development Foundation(12140904200)
文摘Establishing non-human primate models of human diseases is an efficient way to narrow the large gap between basic studies and translational medicine. Multifold advantages such as simplicity of breeding, low cost of feeding and facility of operating make the tree shrew an ideal non-human primate model proxy. Additional features like vulnerability to stress and spontaneous diabetic characteristics also indicate that the tree shrew could be a potential new animal model of human diseases. However, basal physiological indexes of tree shrew, especially those related to human disease, have not been systematically reported. Accordingly, we established important basal physiological indexes of domesticated tree shrews including several factors: (1) body weight, (2) core body temperature and rhythm, (3) diet metabolism, (4) locomotor rhythm, (5) electroencephalogram, (6) glycometabolism and (7) serum and urinary hormone level and urinary cortisol rhythm. We compared the physiological parameters of domesticated tree shrew with that of rats and macaques. Results showed that (a) the core body temperature of the tree shrew was 39.59±0.05 °C, which was higher than that of rats and macaques; (b) Compared with wild tree shrews, with two activity peaks, domesticated tree shrews had only one activity peak from 17:30 to 19:30; (c) Compared with rats, tree shrews had poor carbohydrate metabolism ability; and (d) Urinary cortisol rhythm indicated there were two peaks at 8:00 and 17:00 in domesticated tree shrews, which matched activity peaks in wild tree shrews. These results provided basal physiological indexes for domesticated tree shrews and laid an important foundation for diabetes and stress-related disease models established on tree shrews.
文摘Oxidative status assessment is an initial step in tumor related studies. To the best of our knowledge, this is the first study considering oxidative activity of both serum and tissue specimens in human basal cell carcinoma (BCC), which is the most common tumor in the world. Concentration of Malondialdehide (MDA) in human basal cell carcinoma (BCC) and individually matched normal skin tissue were examined with spectrophotometery method. Fresh normal and cancerous skin paired tissue was obtained from 60 patients who underwent curative BCC resection at one center in Tehran (Razi hospital). Serum Concentration of Malondialdehide (MDA) in these patients and 55 normal subjects were also measured. MDA level in cancerous tissue of patients with skin BCC (1.0 ± 0.14 ng/g) was significantly (p = 0.001) higher than normal neighboring skin tissue (0.3 ± 0.07 ng/g). A remarkable (Not significant, P = 0.18) increase was found in the serum MDA level in patients with skin BCC (8.0 ± 2.3 ng/ml) in comparison with the control subjects (7.3 ± 2.9 ng/ml). A significant positive correlation (r = 0.276, p = 0.03) was found between Serum MDA and skin tissue MDA for non-affected skin tissue (normal neighboring skin), whereas no significant correlation (p > 0.05) was found for cancerous tissue. Cut-point of 5.2 ng/ml of serum MDA concentration showed a screening sensitivity of 95%. There is an active oxidative process in BCC lesions. Serum MDA concentration can be used either as a screening test or a predictor for tissue MDA concentration.
文摘Drought stress strongly affects soil biota and impairs crop production, which under climate change will be exacerbated in semi-arid cropping regions such as the Sahel. Hence soil management systems are needed that can buffer against drought. In West Africa, field studies have found intercropping of millet with the native shrub Piliostigma reticulatum improves soil-plant-water relations, microbial activity and diversity, and suppress parasitic nematodes, which can significantly increase crop yield. However, little information is available on its beneficial or negative effects on soils or crops during water stress. Therefore, the objective was to investigate the impact of P. reticulatum in moderating water stress effects on soil properties and pearl millet (Pennisetum glaucum [L.] R. Br.) productivity. In the greenhouse, soil chemical and microbial properties and millet growth were investigated with a factorial experiment of varying levels of soil moisture (favorable, moderately stressed, or severely stressed water conditions) that was imposed for 55 days on soils containing sole P. reticulatum or millet, or millet + P. reticulatum. The results showed that the presence of P. reticulatum did not buffer soils against water stress in relation to soil chemical and microbial properties measured at the end of the experiment. Severe water stress did significantly decrease the height, number of leaves, and aboveground biomass of millet plants. Additionally, respiration, nematofauna trophic structure and abundance decreased as water stress increased. Lastly, bacterial feeders and plant parasitic nematodes were the most sensitive to severe water stress while fungal feeding nematodes remained unaffected. The results suggested that the intensity of water stress had more negative effects on soil basal respiration rather than soil microbial biomass.
文摘设计一种采用基底应力附加固结法的层状砂土桩基混凝土施工技术,进行层状砂土桩基混凝土动力夯实数值分析,以此为指导进行地基夯实处理,提高基底应力的固结性能,通过对层状砂土基桩混凝土最大荷载作用点产生沉降应力分析,得到层状砂土基桩混凝土最大荷载作用点的应力响应结果,设计出基地应力固结法的砂土基桩混凝土施工技术和试验方案。结果表明,该施工技术能使基底应力消散时间延长,有效满足基底的排水固结处理时间,使得各层土的水平位移基本维持在50 mm以内,避免了水平位移和基桩沉降。承压能力测试显示,地基承载力特征值可达160 k Pa,满足设计要求的120 k Pa,提高承压能力,有效避免了基底最大荷载作用点产生沉降,提高建筑安全性能。
