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991.
Zheyong Huang Yunli Shen Hongmin Zhu Jianfeng Xu Yanan Song Xinying Hu Zhang Shuning Xiangdong Yang Aijun Sun Juying Qian Junbo Ge 《Experimental Animals》2013,62(3):197-203
Cell delivery via the retrograde coronary route boasts less vessel embolism, myocardial
injury, and arrhythmogenicity when compared with those via antegrade coronary
administration or myocardial injection. However, conventional insertion into the coronary
sinus and consequent bleeding complication prevent its application in small animals. To
overcome the complication of bleeding, we described a modified coronary retroinfusion
technique via the jugular vein route in rats with myocardial infarction (MI). A flexible
wire with a bent end was inserted into the left internal jugular vein and advanced slowly
along the left superior vena cava. Under direct vision, the wire was run into the left
cardiac vein by rotating the wire and changing the position of its tip. A fine tube was
then advanced along the wire to the left cardiac vein. This modified technique showed less
lethal hemorrhage than the conventional technique. Retroinfusion via transjugular catheter
enabled efficient fluid or cell dissemination to the majority areas of the free wall of
the left ventricle, covering the infarcted anterior wall. In conclusion, transjugular
cardiac vein catheterization may make retrocoronary infusion a more safe and practical
route for delivering cell, drug, and gene therapy into the infarcted myocardium of
rats. 相似文献
992.
Yanli Li Matthew R. Bonner Richard W. Browne Furong Deng Lili Tian Junfeng Zhang 《Biomarkers》2013,18(7):712-719
AbstractBackground: Despite the in vitro and in vivo evidence, studies are limited in evaluating whether chemokines are potential inflammatory mediators in response to air pollution exposure in humans.Methods: We conducted a panel study coinciding with the Beijing Olympics, when temporary air pollution controls were implemented. We measured a suite of serum chemokines among healthy adults before, during and after the Olympics, respectively. Linear mixed-effect models were used to evaluate changes in chemokine levels over the three time periods.Results: In response to the 50% drop in air pollution levels during the games, levels of RANTES, MCP-2, and TARC decreased by 25.8%, 20.9% and 35.3%, respectively (p?<?0.001) from pre-Olympics, and then increased by 45.8%, 34.9% and 61.5%, respectively (p?<?0.001) after the games when air pollution levels went up again. Similar patterns were observed in subgroup analyses by sex, age, smoking and body mass index. GRO-α and IL-8 decreased significantly during the games (22.5% and 30.4%), and increased non-significantly after the games. Eotaxin-1 only increased significantly from during- to post-games.Conclusions: The strongest associations with air pollution levels were observed among RANTES, TARC and MCP-2. Those chemokines may play important roles in the air pollution-induced inflammatory pathway. 相似文献
993.
Yuan Yuan Zhang Jun Hong Liu Yuan ming Zhou Yu Yan Zhang Ying Liu Ting Yun Gong Jing Wang 《Process Biochemistry》2013,48(8):1119-1125
A new two-phase kinetic model of sporulation of Clonostachys rosea in a new solid-state fermentation (SSF) reactor was proposed. The model including exponential and logistic models was applied to study the simultaneous effect of temperature, initial moisture content, medium thickness and surface porosity of the plastic membrane on C. rosea sporulation. The model fits experimental data very well and allows accurate predictions of spore production. The maximum spore production achieved 3.360 × 1010 (spores/gDM), about 10 times greater than that in traditional SSF reactor(data not shown). The new reactor can provide two times sporulation surface area. Moisture content can be adjusted by changing the surface porosity to meet the spore production. Two mixings carried out during fermentation makes medium loose and results in a mass of new sporulation surface area. Therefore, the new SSF reactor would have great potential for application in bulk spore production of fungal biocontrol agents. 相似文献
994.
995.
Chong Sha Xiao-Wei Yu Meng Zhang Yan Xu 《Journal of industrial microbiology & biotechnology》2013,40(11):1241-1249
The lipase r27RCL from Rhizopus chinensis CCTCC M201021 was heterologously expressed in Pichia pastoris GS115 by simultaneous co-expression with two secretion factors ERO1p and PDI involved in the endoplasmic reticulum (ER). Compared to the expression of the lipase alone (12,500 U/ml), co-expression with these two proteins resulted in the production of larger total quantities of enzymes. The largest increase was seen when the combined ERO1p/PDI system was co-expressed, resulting in approximately 30 % higher enzyme yields (16,200 U/ml) than in the absence of co-expressed secretion factors. The extracellular protein concentration of the recombinant strain Co XY RCL-5 reached 9.39 g/l in the 7-l fermentor. Simultaneously, the fermentation time was also shortened by about 8 h compared to that of the control. The substrate-specific consumption rate (Qs) and the product-specific production rate (Qp) were both investigated in this research. In conclusion, the space–time yield was improved by co-expression with ERO1p and PDI. This is a potential strategy for high level expression of other heterologous proteins in P. pastoris. 相似文献
996.
Guorong Zhang Cuihua Gu Dechun Wang 《Molecular breeding : new strategies in plant improvement》2013,32(1):131-138
The soybean aphid (Aphis glycines Matsumura) is a major pest on soybean [Glycine max (L.) Merr.] in North America. Aphid resistance has been found on plant introduction (PI) 567537, but its genetic characterization is unknown. The objectives of this study were to identify the resistance genes in PI 567537 using molecular markers and validate them in a different genetic background. A mapping population of 86 F4 lines from a cross between PI 567537 and a susceptible parent E00003 was investigated for aphid resistance in both greenhouse and field trials. A genomic region associated with the aphid resistance in PI 567537 was revealed on chromosome 16 (linkage group J) with molecular markers. This locus was coincidently located in the same region as Rag3 and explained most of the phenotypic variation, ranging from 87.4 % in the greenhouse trial to 78.9 % in the field trial. This resistance gene was further confirmed in an F2 population derived from a cross of PI 567537 × Skylla. The segregation of the F2 population indicated that the aphid resistance in PI 567537 was most likely controlled by a single dominant gene, which was the one we mapped in the F4-derived population. This gene was designated Rag3b since it is located in the same region as Rag3. The mapping of the aphid resistance gene in PI 567537 could be useful in marker-assisted selection when employing PI 567537 as an aphid resistance source. 相似文献
997.
Junxiang Zhang Huixia Li Mingke Zhang Maixia Hui Qi Wang Li Li Lugang Zhang 《Molecular breeding : new strategies in plant improvement》2013,32(4):799-805
Orange head Chinese cabbage accumulates significant amounts of carotenoids with enhanced nutritional quality. To develop molecular markers for breeding of Chinese cabbage lines with high carotenoid content and to isolate the candidate gene underlying carotenoid synthesis, we performed fine mapping of the orange locus in a F2S4 mapping population. Genetic analysis revealed that the phenotype of the orange head trait was controlled by a single recessive gene, Br-or. The F2S4 mapping population consisting of 1,724 individuals was developed from the cross between parental lines 11J16 and 11S39-2 by continuous selfing of a single heterozygous individual. Twenty-one tightly linked simple sequence repeat (SSR) and insertion/deletion polymorphism (InDel) markers were obtained. High-resolution genetic mapping of these markers in the F2S4 mapping population placed Br-InDel2 and Br-InDel1 at genetic distances of 0.1 and 0.2 cM, respectively, on either side of the Br-or locus. Based on comparison of these two marker sequences with the fully sequenced Brassica rapa genome, the Br-or locus was delimited to a 16.7 kb genomic region. Three open reading frames (ORFs) were predicted in the target region. ORF1 encoded carotenoid isomerase, which is involved in the isomerization of carotenoids. ORF1 was found to be co-segregated with the Br-or locus and was thus the most likely candidate gene for Br-or. The information obtained here will facilitate the breeding of nutrient-enriched Chinese cabbage through marker-assisted selection and provide a platform for gaining a better understanding of the regulation of carotenoid biosynthesis in these plants. 相似文献
998.
Changlei Guo Fudong Hu Shaoli Zhang Yakun Wang Hengdao Liu 《Genetics and molecular biology》2013,36(2):177-182
Osteoprotegerin (OPG) gene polymorphisms (T245G, T950C and G1181C) have been associated with osteoporosis and early predictors of cardiovascular disease. The aim of this study was to evaluate whether these polymorphisms contribute to cardiovascular disease (CVD) in type 2 diabetic patients. We performed a case-control study with 178 CVD subjects with diabetes and 312 diabetic patients without CVD to assess the impact of variants of the OPG gene on the risk of CVD. The OPG gene polymorphisms were analyzed by using the polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). There was no significant association between the T245G and G1181C polymorphisms and CVD in the additive genetic model (OR = 0.96, 95% CI 0.64–1.45, p = 0.79; OR = 1.06, 95% CI 0.81–1.39, p = 0.65, respectively). However, the C allele of the T950C polymorphism was independently associated with a risk of CVD in type 2 diabetic patients in this genetic model (OR = 1.38, 95% CI 1.07–1.80, p = 0.01). This study provides evidence that the C allele of the T950C polymorphism is associated with increased risk of CVD in diabetic patients. However, well-designed prospective studies with a larger sample size are needed to validate these results. 相似文献
999.
Tao Zhang Hai-Bo Xiang Yu-Qin Zhang Hong-Yu Liu Yu-Zhen Wei Li-Xun Zhao Li-Yan Yu 《Extremophiles : life under extreme conditions》2013,17(5):757-765
The fungal communities associated with three bryophytes species (the liverwort Barbilophozia hatcheri, the mosses Chorisodontium aciphyllum and Sanionia uncinata) in the Fildes Region, King George Island, maritime Antarctica, were studied using clone library analysis. Fungal communities showed low diversity; the 680 clones belonged to 93 OTUs. Of these, 78 belonged to the phylum Ascomycota, 13 to the phylum Basidiomycota, 1 to the phylum Zygomycota, and 1 to an unknown phylum. Among the OTUs, the most common orders in the Ascomycota were Helotiales (42 OTUs) and Chaetothyriales (14 OTUs) and the most common orders in the Basidiomycota were Sebacinales (3 OTUs) and Platygloeales (3 OTUs). Most OTUs clustered within clades that contained phylotypes identified from samples in Antarctic or Arctic ecosystems or from bryophytes in other ecosystems. In addition, we found that host-related factor may shape the fungal communities associated with bryophytes in this region. This is the first systematic study of the fungal community in Antarctic bryophytes to be performed using culture-independent method and the results may improve understanding of the endophytic fungal evolution and ecology in the Antarctic ecosystem. 相似文献
1000.