914 resultados para total protein
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采用微波消解、电感耦合高频等离子体原子发射光谱(ICP-AES)的方法,对62份不同小麦品种(系)中锌、铁、铜、钙、钠和钾的含量进行了测定。同时利用红外线品质测定仪对主要品质指标粗蛋白、湿面筋、沉降值进行了测定。结果表明,不同小麦品种(系)中各种矿质元素的含量存在差异,2006年小麦品种中铁含量变幅为18.55-58.19 ug/g,平均为30.83ug/g ,最高与最低的相差39.64ug/g;锌含量变幅为5.70-25.80 ug/g,平均为15.13ug/g ,最高与最低相差20.10ug/g。2008年小麦品种(系)中铁含量变幅为16.68-52.25 ug/g,平均为30.10ug/g,最高与最低相差35.58ug/g;锌含量变幅为12.29-33.47 ug/g,平均为21.11ug/g,最高与最低相差21.18ug/g;钙含量变幅为167.53-348.80ug/g,平均为248.59ug/g,最高与最低相差192.59ug/g;铜含量变幅为2.32-5.83 ug/g,平均为2.98ug/g,最高与最低的相差3.61ug/g;钾含量变幅为1822.71-4414.91 ug/g,平均为2617.87ug/g,最高与最低的相差2634.72ug/g;钠含量变幅为10.25-39.82 ug/g,平均为23.05ug/g,最高与最低的相差29.57ug/g。 两年不同小麦品种(系)中矿质元素的含量分析结果表明:铁、铜、钙、钠和钾含量年际变化不明显,说明小麦对铁、铜、钙、钠和钾的吸收较稳定;锌含量变化较大,可能受环境的影响比较大。分析各矿质元素含量与粗蛋白、湿面筋、沉降值及元素之间的相关关系,结果表明,锌含量与粗蛋白含量呈极显著正相关关系,相关系数为0.317,与湿面筋含量之间呈显著正相关,相关系数达到0.246;铁含量与粗蛋白含量呈显著的正相关关系,相关系数是0.262;铜、钙、钠和钾含量与粗蛋白含量、湿面筋和沉降值之间存在正相关,但不显著,其中钠与沉降值之间为负相关。表明施锌或铁对提高小麦粗蛋白和湿面筋有显著效应,其余矿质元素有促进作用但不明显。 利用RAPD分子标记技术对川育23、41058、川育20及其父母本进行分析,力图从分子水平找到小麦矿质元素含量之间的差异性,琼脂糖电泳结果表明不同的小麦品种(系)间扩增出了差异条带。 以上研究结果,将对筛选“微量营养强化型”小麦新材料,选育“微量营养强化型”小麦新品种奠定基础。 62 different wheat cultivars was digested with HNO3 in a tightly closed vessel heated under micro-wave,then contents of zinc,iron,copper,calcium,sodium and potassium were determined by inductively coupled plasma-atomic emission spectroscopy(ICP-AES).The main indexes of wheat quality such as total protein、wet glu and sedimentation volume were detected by Infratec 1255 Food & Feed Analyzer at the same time.The obtained results showed that variation for all of the mineral elements concentrations among different cultivars were observed .In 2006, the amplitude variation of the iron content was 18.55-58.19 ug/g,the average value was 30.83ug/g,and 39.64ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the zinc content was 5.70-25.8 ug/g,the average value was 15.13ug/g,and 20.10ug/g between the highest-content cultivar and the lowest one.In 2008, the amplitude variation of the iron content was 16.68-52.25 ug/g,the average value was 30.10ug/g,and 35.58ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the zinc content was 12.29-33.47 ug/g,the average value was 21.11ug/g,and 21.18ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the calcium content was 167.53-348.80ug/g,the average value was 248.59ug/g,and 192.59ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the copper content was 2.32-5.83 ug/g,the average value was 2.98ug/g,and 3.61ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the potassium content was 1822.71-4414.91 ug/g,the average value was 2617.87ug/g,and 2634.72ug/g between the highest-content cultivar and the lowest one; the amplitude variation of the sodium content was 10.25-39.82 ug/g,the average value was 23.05ug/g,and 29.57ug/g between the highest-content cultivar and the lowest one. Analysis was made on the annual variation of mineral elements content in different Wheat cultivars ,the result shows:there is no obvious difference of iron ,copper ,sodium、calcium and potassium concentrations in wheat cultivars, suggesting the absorption of the iron, copper, sodium、calcium and potassium by wheat are relatively steady ,but zinc concentrations change obviously ,maybe influenced heavily by environment . The correlation between mineral elements 、mineral elements and total protein、mineral elements and sedimentation volume as well as mineral elements and wet glut were analysed in this paper, the result showed that there was significant positive correlation between zinc content and total protein (the correlation coefficient is 0.317), positive correlation between zinc content and wet glu (the correlation coefficient is 0.246), positive correlation between iron content and total protein (the correlation coefficient is 0.262). there was positive but not obvious correlation between the contents of copper, calcium, sodium or potassium and total protein, wet glut or sedimentation volume,among which was negative correlation between sodium and sedimentation volume.It was indicated zinc or iron fertilization has prominent effects in improving the total protein in wheat, the rest mineral elements have Non- obvious facilitation. The study then forecasted the genetic difference of different wheat by the molecular marker of RAPD in order to find differences in molecular level. Chuanyu23、41058、chuanyu20 as well as their male and female parents were analysed by RAPD markers,Agarose gel electrophoresis of DNA revealed the appearance of differential bands . The above-mentioned results of this study establish the foundation to screening the new materials of wheat of " strengthening type of micro- nutrition ", and to breeding the new wheat cultivars of" strengthening type of micro- nutrition ".
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组特殊自养氨氧化混合种群,表现:无机环境种群生长迅速、生物量高;在一个完全无机的自养生长环境中,不仅保持高氨氧化速率,并出现丰富的异养微生物种群;该种群置于异养、厌氧环境中,迅速表现出产氢特征。对于这样一个特殊的生态体系,研究其共生机理,以及联接这些种群之间的碳源和能源问题,将具有非常重要意义。我们拟从种群特征、细胞表面分泌产物、游离体系产物多糖、蛋白和脂肪酸方面开展研究。 第一部分,自养氨氧化混合种群的基本特征。采用氨氧化培养基,进行种群氨氧化特征研究;采用扫描电镜观察自养混合种群的微观特征;沉降、离心去除微生物种群,分析水相中的总有机碳、糖类等物质;利用LB培养基进行种群的分离、纯化,并采用DGGE手段对微生物种群结构进行分析。结果表明,接入菌种后(2/5000(V/V)),培养液中氨(200mg/L)在3-5天内快速降解;亚硝酸盐与氨氮变化呈负相关趋势,仅有少量硝酸盐含量(< 30mg/L)。氨氧化种群的生物量增长与氨氧化趋势一致,初始生物量7.75 mg/L(蛋白含量),3-5天后生物量快速增长,并达到最高63.06 mg/L(蛋白含量)。电镜图片显示,种群外包裹一层粘液。离心除去菌体后,检测培养液总有机碳和糖的含量,同样表现出与生物量增长相似的特征,分别由初始的3.73、2.35 mg/L,3-5内天迅速增加,并分别达到最大值35.19、27.45 mg/L。经初步分离、纯化并对纯化菌株进行测序,获得了10株异养微生物分别为布鲁氏菌科苍白杆菌属、纤维单孢菌、类芽孢菌属、黄杆菌属、无色杆菌、鞘脂单胞菌、嗜麦芽寡养单胞菌、噬氢菌属、硫红球菌、假单胞菌;DGGE显示,约有20分条离带,我们对其中的两条优势条带进行切割回收测序,鉴定为欧洲亚硝化单胞菌(Nitrosomonas eur)。 第二部分:混合种群自养-异养菌共生的可能机制。在对微生物种群特征初步分析基础上,针对胞外糖类组分可能被微生物代谢分解,我们重点对微生物细胞蛋白质与糖类进行分析。采用超声结合RIPA裂解液裂解,SDS-PAGE电泳分析混合种群总蛋白种类,并通过氨基酸分析仪及红外光谱法分析氨基酸组成及蛋白红外特征。采用超声破碎结合反复冻融对细胞样品进行处理,提取液采用醇沉、Sevage脱氮白,凝胶过滤方法脱盐和分级分离。对提取物的糖分析包括:紫外扫描,红外光谱,核磁共振,单糖组成分析;扫描电镜观察菌群破裂现象。SDS-PAGE分析结果表明:氨氧化种群不同生长阶段都显示出42kD蛋白表达量很高,d4时42kD蛋白表达已经很强,4-7d内一直持续这种过量表达,直到d8后表达开始减弱。说明42kD蛋白可能与氨氧化密切相关。红外光谱分析显示:细胞提取物的特征峰分布在3427.42cm-1、1718.18 cm-1和1681.72 cm-1、1160.07和1086.74 cm-1,分别对应为OH、 C=O、C-O-C基团,表明具有蛋白的典型特征;氨基酸分析显示蛋白中的Gly,Asp,Ala,Glu含量相对较高。 提取物中胞外多糖分离谱图得到不均一组分,共得到6个收集峰;紫外扫描在201-213 nm处有多糖吸收峰,同样表明多糖成分不均一性;多糖红外光谱特征峰主要分别在3400.49 cm-1、2920.28 cm-1、1154.54和1087.52 cm-1,对应OH、-CH2- or CH 、C-O-H or C-O-C等多糖特征基团;多糖提取物核磁共振1H d4.3~5.9之间出现强吸收峰,这是1H中,多糖存在的明显证据,1H NMR中,其中O-乙酰基的甲基上的氢信号为d1.1~1.3之间。糖肟全苯甲酸酯衍生物的HPLC测定中,得到单一的单糖峰,由于时间问题,还未进行更深入的试验;电镜图片显示,种群中的细胞有大量的破裂现象。 实验表明,自养氨氧化混合种群显示出快速的氨氧化速率,氨氧化过程生物量和有机质的增加明显。微生物种群包裹粘液层,并分离纯化出大量的异养菌;去除菌体后的游离培养液中存在有机质(包括多糖)说明无机自养生长体系中存在异养菌生长、繁殖的二次碳源;细胞提取物中蛋白条带数目多、种类丰富;细胞多糖提取物具有明显的多糖特征,以及单糖的存在。结合种群的显微特征和游离体系中的有机质的检测结果,我们认为,无机自养生长体系中,种群细胞生长过程中发生的破裂现象可能是导致大量的蛋白、多糖释放到游离胞外,并成为其他异养菌生长的碳源和氮源。这可能是自养体系中,大量异养菌共生的可能机制,至于是什么原因引起种群生长过程中产生的破裂现象,还有待下一步深入研究。 A group of mixed autotrophic ammonia oxidizing populations, having much biological characteristic tested by concerned personnel for pilot test: Performed rapid population growth and obtained high biomass in inorganic environment; Not only maintained a high rate of ammoxidation, promoted a wealth of heterotrophic microbial populations growth in a totally inorganic and autotrophic growth environment; Placed in heterotrophic and anaerobic environment,had the performance characteristics that could rapidly produce hydrogen.For such a special ecological system, Study its symbiotic mechanism and the connection between these populations of carbon and energy issues, will have a very important significance. We intended from the characteristics of the population, the secretion product of cell surface, free substance in the liquid medium like polysaccharide, protein and fatty acids carrying out research. Part I: The basic features of mixed autotrophic ammonia oxidizing populations . Use inorganic liquid medium, processed study for ammonia oxidation characteristics of the population; we used scanning electron microscopy to get micro-features of autotrophic ammonia oxidizing populations .The medium was carried out settlement and centrifugal then removed the microbial populations, after all of that we analysis the water phase for total organic carbon(TOC), carbohydrate and other substances; Solid ammonia oxidizing medium was adopted to separation and purification of population, DGGE means was for structure analysis of microbial population. The results showed that after the inoculum of bacteria (2 / 5000 (V / V)), ammonia in the culture medium (200 mg / L) was rapid degradation in 3-5 days; ammonia and nitrite have the negative correlation between changes in the trend, then only a small amount of nitrate content (<30mg / L). The biomass growth of ammoxidation population in line with the trend of ammonia oxidation, the initial volume of it was 7.75 mg / L (protein content), in 3-5 days upto 63.06 mg / L (protein content). Electron microscope image showed, the populations were wrapped in a layer of mucus, including the a large number ruptted micorbe , Centrifuge to remove bacteria, then detected the medium for total organic carbon and sugar content, result took on the same characteristics with biomass growth, that were from the initial 3.73、2.35 mg / L respectively, in 3-6 days achieved rapid increase in the maximum to 35.19、27.45 mg / L respectively. After initial separation、 purification ,then processed sequencing to strains purified and got the result that there were 10 heterotrophic microorganisms : Brucella Branch pale bacillus, Cellu lomonas, Bacillus species category, a Flavobacterium, colorless Bacteria, Aeromonas sheath fat, little support maltophilia Aeromonas, macrophages species hydrogen, sulphur-MI, Pseudomonas bacteria spores; DGGE display, there were 20 separation bands approximately. Part II: Mixed populations that autotrophic - heterotrophic bacteria symbiotic mechanism. On the basis of preliminary analysis of microbial population characteristics, aiming at extracellular carbohydrate components might be decomposition by microbial, we focused on microbial cell protein and carbohydrate analysis. Using ultrasound combined with RIPA lysis cracking the cells, SDS-PAGE electrophoresis analysis the total protein species of the population, and through the amino acid analyzer studied the compositions of amino acid and infrared spectroscopy analysis of a protein infrared characteristics. Using ultrasound combined with repeatedly freezing and thawing to treated the cell sample, then took the means that alcohol precipitation, deproteinization by Sevage, gel filtration aimed at desalination and grade separation to deal with the lysates . The extraction of sugar analysis included: UV scanning, IR, NMR, single-sugar composition analysis. SDS-PAGE analysis showed that: 42 kD protein expression was very high at different growth stages of mixed autotrophic ammonia oxidizing populations , on the fourth day, 42 kD protein expression had been very strong, 4-7d, it had continued this excessive expression, then started to weaken after 7 days. 42 kD protein that might be closely associated with ammonia oxidation. Infrared spectral analysis showed that: cell extracts with the characteristic that the peak distribution in 3427.42 cm-1、1718.18 cm-1 and 1681.72 cm-1、1160.07 cm-1 and 1086.74 cm-1 corresponding to OH、C = O、C-O-C Groups which had the typical characteristics of protein; and analysis showed that amino acids including Gly, Asp, Ala, Glu ,the content in the protein is relatively high. Exopolysaccharide in the extracts had the separation map that it was uneven, received a total of six collection peaks by the detection mode of phenol-sulphruic acid method ; ultraviolet scan in the 201-213 nm department had polysaccharide absorbing peak, the same ingredients that polysaccharide heterogeneity; infrared polysaccharide spectral characteristics of the main peak at 3400.49 cm-1, 2920.28 cm-1, 1154.54 and 1087.52 cm-1, corresponding OH,-CH2-or CH, C-O-H or C-O-C;and other characteristics of polysaccharide group; 1H NMR of polysaccharide extract appeared absorption peak between d4.3 ~5.9, which is the apparent evidence of polysaccharide, In 1H NMR, the hydrogen signal of one of O-acetyl was between 1.1 to 1.3. The determination of Sugar oxime whole benzoate derivatives by HPLC, there was a single-sugar peak, as a matter of time, yet more in-depth test. Summary: Mixed autotrophic ammonia oxidizing populations show us that it had the ability in ammonia oxidizing and it was great, organic matter and biomass increased significantly in the process of ammonia oxidation. Microbial populations was wrapped up slime layer, the phenomenon of cell breakdown obviously, and there were a lot of separation and purification of the heterotrophic bacteria; a lot of organic matter (including polysaccharides)remined in the medium that removal of cell indicated the inorganic system existed secondary carbon sources that could be used by the heterotrophic bacteria ; there were a large number proteins bands of cell extract, rich variety; cell extracts of polysaccharide had obvious characteristics of polysaccharide, and the existence evidence of single-sugar. Combined population of microscopic characteristics and free of organic matter in the test results, we believe that the health of inorganic system, population growth occurred in the course of the breakdown of the phenomenon is likely to lead to a lot of protein and polysaccharide released into the extracellular free, And other heterotrophic bacteria use them to the growth as carbon and nitrogen. This may be autotrophic system, the large number of heterotrophic bacteria symbiotic mechanism.
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以奥利亚罗非鱼(Oreochromis aureus)为实验对象,设计了3种不同的摄食类型,分别是鲜活饵料组、饥饿3周后饱食投喂组和人工饲料组。鲜活饵料组投喂冰冻赤子爱胜蚓,利用蚯蚓体内丰富的营养成分和活性物质,以期获得奥利亚罗非鱼良好的生长状况;饥饿后饱食组是指饥饿3周后,以人工饲料饱食投喂2周,用于研究饥饿与补偿生长获得快速生长时血液理化指标的变化情况;人工饲料组作为对照组。纯淡水条件下养殖,水温25±2℃。测定了奥利亚罗非鱼在3种摄食类型饲喂下某些血液生理生化指标变化的情况,并将指标变化情况与增重率做相关性分析,试图找出能够反映奥利亚罗非鱼生长性能的血液生理生化指标。 研究结果表明,奥利亚罗非鱼在饥饿3周后获得了补偿生长,补偿生长时的增重率和特定生长率显著高于人工饲料组(P<0.05),高于鲜活饵料组,但差别不显著;相关性分析研究表明血清总蛋白、胆固醇、四碘甲状腺原氨酸(T4)与增重率极显著相关(P<0.01),血红蛋白显著相关(P<0.05),红细胞、白细胞、碱性磷酸酶高度相关(相关系数为0.580、0.551和0.557),因此,建议血清总蛋白、胆固醇和血红蛋白可作为能够反映罗非鱼生长性能的新指标。 根据序列设计引物,PCR反应条件:变性温度:95 ℃,3 min;退火温度:57℃,20 sec;延伸温度:72℃,5 min,共36个循环,从牙鲆、黑鲪和鲈鱼中克隆出胰岛素样生长因子(IGF-Ⅰ)部分序列,首次证实了IGF-Ⅰ在3种海水鱼中的存在。 利用蛋氨酸与ZnSO4•7H2O,在pH 5.5、80℃下,反应1小时,采用蛋氨酸与硫酸锌2:1的配料比,合成出了产物蛋氨酸螯合锌,蛋氨酸螯合锌外观白色,粉状,室温下微溶于水,不溶于乙醇,并用原子吸收光谱法测定其含锌量为15%,螯合率为88.2%。
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Variations of cellular total lipid, total carbohydrate and total protein content of two dominant bloom-forming species (Skeletonema costatum and Prorocentrum donghaiense) isolated from the Yangtze River Estuary were examined under six different nutrient conditions in batch cultures. Daily samples were collected to estimate the cell growth, nutrient concentration and three biochemical compositions content during 7 days for S. costatum and the same sampling procedure was done every other day during 10 days for P. donghaiense. Results showed that for S. costatum, cellular total lipid content increased under phosphorus (P) limitation, but not for nitrogen (N) limitation; cellular carbohydrate were accumulated under both N and P limitation: cellular total protein content of low nutrient concentration treatments were significantly lower than that of high nutrient concentration treatments. For P. donghaiense, both cellular total lipid content and total carbohydrate content were greatly elevated as a result of N and P exhaustion, but cellular total protein content had no significant changes under nutrient limitation. In addition, the capability of accumulation of three biochemical constituents of P. donghaiense was much stronger than that of S. costatum. Pearson correlation showed that for both species, the biochemical composition of three constituents (lipid, carbohydrate and protein) had no significant relationship with extracellular N concentration, but had positive correlation with extracellular and intracellular P concentration. The capability of two species to accumulate cellular total lipid and carbohydrate under nutrient limitation may help them accommodate the fluctuating nutrient condition of the Yangtze River Estuary. The different responses of two species of cellular biochemical compositions content under different nutrient conditions may provide some evidence to explain the temporal characteristic of blooms Caused by two species in the Yangtze River Estuary. (C) 2008 Elsevier B.V. All rights reserved.
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This thesis has been focused on the proteomic characterization of human saliva from donors of different ages, starting from birth up to adult age, and pediatric brain tumor tissues. The first study has been performed in order to compare the acid-insoluble fraction of saliva from preterm with at-term newborns and adults and establish if differences exist. In the second study medulloblastoma and pilocytic astrocytoma pediatric brain tumor extracts have been compared. In both studies 2- DE analysis was coupled with high resolution tandem mass spectrometry (MS/MS). The proteomic characterization of the acid-insoluble fractions of saliva from preterm newborns allowed to integrate data previously obtained on the acid-soluble fraction by HPLC-electrospray ionization (ESI)-mass spectrometry (MS), and to evidence several differences between preterm newborns, at-term newborns and adults. Spots differentially expressed between the three groups, according to image analysis of the gels, were submitted to in-gel tryptic digestion and the peptide mixture analyzed by high performance HPLC-ESI-MS/MS for their characterization. By this strategy, we identified three over-expressed proteins in atterm newborns with respect to preterm newborns and adults (BPI fold-containing family A member 1, two proteoforms of annexin A1, and keratin type 1 cytoskeletal 13), and several over-expressed proteins in adults (fatty acid-binding protein, S100A6, S100A7, two proteoforms of S100A9, several proteoforms of prolactin-inducible protein, Ig kappa chain, two proteoforms of cystatin SN, one proteoform of cystatin S and several proteoforms of α-amylase 1). Moreover, for the first time, it was possible to assign by MS/MS four spots of human saliva 2-DE, already detected by other authors, to different proteoforms of S100A9. The strategy applied used a sequential staining protocol to the 2-DE gels, first with Pro-Q Diamond, that allows specific detection of phosphoproteins, and successively with total protein SYPRO Ruby stain. In the second study, proteomic analysis of two pediatric brain tumor tissues pointed out differences between medulloblastoma, the prevalent malignant tumor in childhood, and pilocytic astrocytoma, the most common, that only rarely shows a malignant progression. Due to the limited availability of bioptic tissue, the study was performed on pooled tumor tissues, and was focused on acid-insoluble fraction to integrate the characterization performed by a group of colleagues in Rome on the acid-soluble fraction by high performance HPLC-ESI-MS/MS. The results indicated that the two tumors exhibit different proteomic profiles and evidenced interesting differential expression of several proteins. Among them, peroxiredoxin- 1, peptidyl-prolyl cis–trans isomerase A, heterogeneous nuclear ribonucleoproteins A2/B1, mitochondrial isoform of malate dehydrogenase, nucleoside diphosphate kinase A, glutathione S-transferase P and fructose bisphosphate aldolase A resulted significantly over-expressed in medulloblastoma while glial fibrillary acidic protein, serotransferrin, α crystallin B chain, ferritin light chain, annexin A5, fatty acid-binding protein (brain), sorcin and apolipoprotein A-I resulted significantly over-expressed in pilocytic astrocytoma. In conclusion, the work done allowed to evidence the usefulness of using an integrated bottom-up/top-down approach, based on 2-DE-MS analysis and high performance MS in order to obtain a complete characterization of the proteome under investigation, revealing and identifying, not only peptides and small proteins, but also proteins with higher MW, that often it is not possible to identify by using exclusively a top-down ESI-MS approach.
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A significant challenge in environmental toxicology is that many genetic and genomic tools available in laboratory models are not developed for commonly used environmental models. The Atlantic killifish (Fundulus heteroclitus) is one of the most studied teleost environmental models, yet few genetic or genomic tools have been developed for use in this species. The advancement of genetic and evolutionary toxicology will require that many of the tools developed in laboratory models be transferred into species more applicable to environmental toxicology. Antisense morpholino oligonucleotide (MO) gene knockdown technology has been widely utilized to study development in zebrafish and has been proven to be a powerful tool in toxicological investigations through direct manipulation of molecular pathways. To expand the utility of killifish as an environmental model, MO gene knockdown technology was adapted for use in Fundulus. Morpholino microinjection methods were altered to overcome the significant differences between these two species. Morpholino efficacy and functional duration were evaluated with molecular and phenotypic methods. A cytochrome P450-1A (CYP1A) MO was used to confirm effectiveness of the methodology. For CYP1A MO-injected embryos, a 70% reduction in CYP1A activity, a 86% reduction in total CYP1A protein, a significant increase in beta-naphthoflavone-induced teratogenicity, and estimates of functional duration (50% reduction in activity 10 dpf, and 86% reduction in total protein 12 dpf) conclusively demonstrated that MO technologies can be used effectively in killifish and will likely be just as informative as they have been in zebrafish.
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Antimicrobial peptides play an important role in host defence, particularly in the oral cavity where there is constant challenge by microorganisms. The a-defensin antimicrobial peptides comprise 30–50% of the total protein in the azurophilic granules of human neutrophils, the most abundant of which is human neutrophil peptide 1 (HNP-1). Despite its antimicrobial activity, a limiting factor in the potential therapeutic use of HNP-1 is its chemical synthesis with the correct disulphide topology. In the present study, we synthesised a range of truncated defensin analogues lacking disulphide bridges. All the analogues were modelled on the C-terminal region of HNP-1 and their antimicrobial activity was tested against a range of microorganisms, including oral pathogens. Although there was variability in the antimicrobial activity of the truncated analogues synthesised, a truncated peptide named 2Abz23S29 displayed a broad spectrum of antibacterial activity, effectively killing all the bacterial strains tested. The finding that truncated peptides, modelled on the C-terminal ß-hairpin region of HNP-1 but lacking disulphide bridges, display antimicrobial activity could aid their potential use in therapeutic interventions.
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Background: Bronchoscopic bronchoalveolar lavage in children to investigate bronchia disorders such as asthtna has both ethical and procedural difficulties.
Objective: The aim of this study was to establish a standardized non-bronchoscopic method to perform bronchoalveolar lavage in children attending for elective surgery to obtain normal cellular data.
Methods: Bronchoalveolar lavage was performed on normal children (n= 55) by infusing saline (20 mL) through an 8 FG suction catheter passed after endotracheal intubation. Oxygen saturation, heart and respiratory rate were monitored during the bronchoalveolar lavage procedure. Cellular analysis and total protein estimation of the lavage fluid were performed. Epithelial lining fluid volume was calculated (n = 15) using the urea dilution method.
Results: The procedure was well tolerated by all children. Total cell count and differential cell count for children (macrophages 70.8 ± 2.3%, lymphocytes 3.8 ± 0.6%, neutrophils 5,7 ± 1.0%, eosinophils 0.14 ± 0.03%. epithelial cells 19.6 ± 2.1%, mast cells 0.21 ± 0.02%) were similar to those reported for adults. Age and sex comparisons revealed no differences between groups. The mean total protein recovered in the cell free supernatant was 49.72 ± 4.29 mg/L and epithelial lining fluid volume was 0.82 ± 0.11% of return lavageate.
Conclusion This method allows bronchoalveolar lavage to be performed safely and quickly on children attending for routine elective surgery. Using this method and taking the ‘window of opportunity’ of elective surgery, the presence or absence of airway inflammation could be studied in children with various patterns of asthma during relatively asymptomatic periods.
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Mitochondrial free radical formation has been implicated as a potential mechanism underlying degenerative senescence, although human data are lacking. Therefore, the present study was designed to examine if resting and exercise-induced intramuscular free radical-mediated lipid peroxidation is indeed increased across the spectrum of sedentary aging. Biopsies were obtained from the vastus lateralis in six young (26 ± 6 yr) and six aged (71 ± 6 yr) sedentary males at rest and after maximal knee extensor exercise. Aged tissue exhibited greater (P < 0.05 vs. the young group) electron paramagnetic resonance signal intensity of the mitochondrial ubisemiquinone radical both at rest (+138 ± 62%) and during exercise (+143 ± 40%), and this was further complemented by a greater increase in a-phenyl-tert-butylnitrone adducts identified as a combination of lipid-derived alkoxyl-alkyl radicals (+295 ± 96% and +298 ± 120%). Lipid hydroperoxides were also elevated at rest (0.190 ± 0.169 vs. 0.148 ± 0.071 nmol/mg total protein) and during exercise (0.567 ± 0.259 vs. 0.320 ± 0.263 nmol/mg total protein) despite a more marked depletion of ascorbate and uptake of a/ß-carotene, retinol, and lycopene (P < 0.05 vs. the young group). The impact of senescence was especially apparent when oxidative stress biomarkers were expressed relative to the age-related decline in mitochondrial volume density and absolute power output at maximal exercise. In conclusion, these findings confirm that intramuscular free radical-mediated lipid peroxidation is elevated at rest and during acute exercise in aged humans.
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The association of very-low-density lipoprotein (VLDL) with atherosclerosis remains controversial. However, studies have shown that oxidative modification of VLDL can promote foam cell formation, leading to the development of atherosclerosis. A rapid method is described which will allow the significance of VLDL oxidation to be assessed in clinical studies. VLDL was isolated from heparinized plasma by a 1-h, single spin ultracentrifugation. Total protein was standardized to 25 mg/L. Oxidation was promoted by the addition of copper ions (17.5 mu mol/L, final concentration) incubated at 37 degrees C. Conjugated diene production was followed at 234 nm. Total assay preparation time was 2 h. Urate greatly inhibited the oxidation of VLDL and was successfully removed by size exclusion chromatography. VLDL isolated from frozen plasma (-70 degrees C) was stable for 15 weeks. This simple, rapid method for the isolation of VLDL may be applied to assess the significance of VLDL oxidation in disease.
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Peptide-specific antibody AABI, raised to the C-terminal 13 amino acids of Arabidopsis thaliana beta 1 tubulin, identifies a single electrophoretically separable beta-tubulin on 2-D-gel Western blots of total protein extracts from A. thaliana seedlings. We show that AABI crossreacts with two of the eight polyglutamylated beta-tubulin isoforms present in purified Nicotiana tabacum tubulin fractionated by high-resolution isoelectric focussing. Immunolocalisation studies using AAB1 revealed that the two N. tabacum polyglutamylated beta 1-tubulin isoforms are utilised in all four plant microtubule arrays (the interphase cortical array, the preprophase band, the spindle and the phragmoplast) indicating that there is no apparent subcellular sorting of these isotypes.
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PURPOSE. Vascular endothelial growth factor (VEGF)-A and placental growth factor (PIGF) are members of a large group of homologous peptides identified as the VEGF family. Although VEGF-A is known to act as a potent angiogenic peptide in the retina, the vasoactive function of PIGF in this tissue is less well defined. This study has sought to elucidate the expression patterns and modulatory role of these growth factors during retinal vascular development and hyaloid regression in the neonatal mouse. METHODS. C57BL6J mice were killed at postnatal days (P)1, P3, P5, P7, P9, and P11. The eyes were enucleated and processed for in situ hybridization and immunocytochemistry and the retinas extracted for total protein or RNA. Separate groups of neonatal mice were also injected intraperitoneally daily from P2 through P9 with either VEGF-neutralizing antibody, PIGF-neutralizing antibody, isotype immunoglobulin (Ig)-G, or phosphate-buffered saline (PBS). The mice were then perfused with fluorescein isothiocyanate (FITC)-dextran, and the eyes were subsequently embedded in paraffin wax or flat mounted. RESULTS. Quantitative (real-time) reverse transcription-polymerase chain reaction (RT-PCR) demonstrated similar expression patterns of VEGF-A and PIGF mRNA during neonatal retinal development, although the fluctuation between time periods was greater overall for VEGF-A. The localization of VEGF-A and PIGF in the retina, as revealed by in situ hybridization and immunohistochemistry, was also similar. Neutralization of VEGF-A caused a significant reduction in the hyaloid and retinal vasculature, whereas PIGF antibody treatment caused a marked persistence of the hyaloid without significantly affecting retinal vascular development. CONCLUSIONS. Although having similar expression patterns in the retina, these growth factors appear to have distinct modulatory influences during normal retinal vascular development and hyaloid regression.
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Neutrophil elastase (NE), a biomarker of infection and inflammation, correlates with the severity of several respiratory diseases including cystic fibrosis (CF) however, its detection and quantification in biological samples is confounded by a lack of robust methodologies. Standard assays using chromogenic or fluorogenic substrates are not specific when added to complex samples containing multiple proteolytic and hydrolytic enzymes, resulting in an over-estimation of the target protease. ELISA systems measure total protein levels which can be a mixture of latent, active and protease-inhibitor complexes. We have therefore developed a novel immunoassay (NE-Tag ELISA), incorporating an activity dependent ProteaseTag™ and a specific antibody step, which is selective and specific for the capture of active NE. The objective of this study was to clinically validate NE-Tag ELISA for the detection of active NE in sputum from CF patients. Sputum (n=45) was recovered from CF patients hospitalised for acute exacerbation. Sol was recovered and analysed for NE activity using the NE-Tag ELISA and two fluorogenic substrate-based assays [1. Suc-AAPV-AMC (Sigma) and 2. InnozymeTM Immunocapture assay (Calbiochem)]. NE activity between assays and with a range of clinical parameters was correlated.A highly significant correlation was shown between assays. NE activity (NE-Tag) further correlated appropriately with clinical parameters: inversely with FEV1 (p = 0.036) and positively with CRP (p = 0.035), neutrophils and total white cell counts (p < 0.001). The InnozymeTM assay showed similar correlations with the clinical parameters (with the exception of CRP). No correlations with any of the clinical parameters were observed when NE was measured using the standard fluorogenic substrate.
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Introduction: Neutrophil elastase (NE) is a serine protease implicated in the pathogenesis of several respiratory diseases including cystic fibrosis (CF). The presence of free NE in BAL is a predictor of subsequent bronchiectasis in children with CF (Sly et al, 2013, NEJM 368: 1963-1970). Furthermore, children with higher levels of sputum NE activity (NEa) tend to experience a more rapid decline in FEV1 over time even after adjusting for age, gender and baseline FEV1 (Sagel et al, 2012, AJRCCM 186: 857-865). Its detection and quantification in biological samples is however confounded by a lack of robust methodologies. Standard assays using chromogenic or fluorogenic substrates are not specific when added to complex samples containing multiple proteolytic and hydrolytic enzymes. ELISA systems measure total protein levels which can be a mixture of latent, active and protease-inhibitor complexes. We have therefore developed a novel assay (ProteaseTag™ Active NE Immunoassay), which couples an activity dependent NE-Tag with a specific antibody step, resulting in an assay which is both selective and specific for NEa. Aims: To clinically validate ProteaseTag™ Active NE for the detection of free NEa in BAL from children with CF. Methods: A total of 95 paediatric BAL samples [CF (n=76; 44M, 32F) non-CF (n=19; 12M, 7F)] collected through the Study of Host Immunity and Early Lung Disease in CF (SHIELD CF) were analysed for NEa using ProteaseTag™ Active NE (ProAxsis Ltd) and a fluorogenic substrate-based assay utilising Suc-AAPV-AMC (Sigma). IL-8 was measured by ELISA (R&D Systems). Results were analysed to show comparisons in free NEa between CF and non-CF samples alongside correlations with a range of clinical parameters. Results: NEa measured by ProteaseTag™ Active NE correlated significantly with age (r=0.3, p=0.01) and highly significantly with both IL-8 (r=0.4, p=<0.0001) and the absolute neutrophil count (ANC) (r=0.4, p=<0.0001). These correlations were not observed when NEa was measured by the substrate assay even though a significant correlation was found between the two assays (r=0.8, p<0.0001). A trend towards significance was found between NEa in the CF and non-CF groups when measured by ProteaseTag™ Active NE (p=0.07). Highly significant differences were found with the other inflammatory parameters between the 2 groups (IL-8: p=0.0002 and ANC: p=0.006). Conclusion: NEa as a primary efficacy endpoint in clinical trials or as a marker of inflammation within the clinic has been hampered by the lack of a robust and simple to use assay. ProteaseTag™ Active NE has been shown to be a specific and superior tool in the measurement of NEa in paediatric CF BAL samples (supporting data from previous studies using adult CF expectorated samples). The technology is currently being transferred to a lateral flow device for use at Point of Care. Acknowledgements: This work was supported by the National Children’s Research Centre, Dublin (SHIELD CF) and grants from the Medical Research Council and Cystic Fibrosis Foundation Therapeutics.
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RATIONALE: Cigarette smoke exposure is associated with an increased risk of the acute respiratory distress syndrome (ARDS); however, the mechanisms underlying this relationship remain largely unknown.
OBJECTIVE: To assess pathways of lung injury and inflammation in smokers and non-smokers with and without lipopolysaccharide (LPS) inhalation using established biomarkers.
METHODS: We measured plasma and bronchoalveolar lavage (BAL) biomarkers of inflammation and lung injury in smokers and non-smokers in two distinct cohorts of healthy volunteers, one unstimulated (n=20) and one undergoing 50 μg LPS inhalation (n=30).
MEASUREMENTS AND MAIN RESULTS: After LPS inhalation, cigarette smokers had increased alveolar-capillary membrane permeability as measured by BAL total protein, compared with non-smokers (median 274 vs 208 μg/mL, p=0.04). Smokers had exaggerated inflammation compared with non-smokers, with increased BAL interleukin-1β (p=0.002), neutrophils (p=0.02), plasma interleukin-8 (p=0.003), and plasma matrix metalloproteinase-8 (p=0.006). Alveolar epithelial injury after LPS was more severe in smokers than non-smokers, with increased plasma (p=0.04) and decreased BAL (p=0.02) surfactant protein D. Finally, smokers had decreased BAL vascular endothelial growth factor (VEGF) (p<0.0001) with increased soluble VEGF receptor-1 (p=0.0001).
CONCLUSIONS: Cigarette smoke exposure may predispose to ARDS through an abnormal response to a 'second hit,' with increased alveolar-capillary membrane permeability, exaggerated inflammation, increased epithelial injury and endothelial dysfunction. LPS inhalation may serve as a useful experimental model for evaluation of the acute pulmonary effects of existing and new tobacco products.