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81.
A new polymeric coating for protein microarrays 总被引:3,自引:0,他引:3
Despite the increasing interest in arraying proteins in a high-density format, several technical issues still impede the development of protein microarray technology. One of the major problems is the availability of substrates that are able to bind native proteins with high density. In this study, we investigated the suitability of a novel surface as a support for protein microarrays. A polymeric glass coating is obtained by physical adsorption of a N,N-dimethylacrylamide (DMA), N,N-acryloyloxysuccinimide (NAS), and [3-(methacryloyl-oxy)propyl]trimethoxysilyl (MAPS) copolymer. The coating procedure provides a fast and inexpensive method of producing hydrophilic functional surfaces. The slide performance was investigated in a protein-protein interaction experiment and in the assessment of rheumatoid factor (RF) in human serum samples. The results demonstrate that the ligands immobilized on the polymeric surface maintain an active conformation and are easily accessible, providing a detection limit of 54amol/spot. Moreover, in the RF assay, after hybridization with the sera, the slides have a low background, leading to a detection limit of 900amol/spot. 相似文献
82.
Warner ML Harley K Bradman A Vargas G Eskenazi B 《Obesity (Silver Spring, Md.)》2006,14(11):1966-1974
Objective: The prevalence of overweight in United States children, 2 to 5 years old, has increased 2‐fold since 1975, with the highest prevalence in Mexican Americans. The objective of this study was to determine the association between current soda consumption and overweight in 2‐year‐old Mexican‐American children. Research Methods and Procedures: The Center for the Health Assessment of Mothers and Children of Salinas study is a longitudinal study of the health of low‐income Latino pregnant women and their children living in the Salinas Valley, CA. Six hundred pregnant women were enrolled (October 1999 to October 2000), and their children were followed until 2 years of age. This cross‐sectional analysis includes the 354 children who completed the 2‐year follow‐up interview. Standing height (centimeters) and weight (grams) were measured at 2 years. Overweight was defined as ≥95th percentile of the sex‐specific BMI for each child's age. Results: Fifty‐five (15.5%) children were overweight. Over half (56%) reported consuming any soda in the last week. After covariate adjustment, compared with no soda consumption, <1 soda/d was not related to overweight (adjusted odds ratio, 0.97; 95% confidence interval, 0.47, 1.99), but ≥1 soda/d was significantly associated with overweight (adjusted odds ratio, 3.39; 95% confidence interval, 1.43, 8.07), and the test for trend was significant (p = 0.02). Discussion: At 2 years of age, the prevalence of overweight among the Center for the Health Assessment of Mothers and Children of Salinas cohort is higher than the national prevalence estimate for Mexican‐American 2‐ to 5‐year‐old children and is significantly associated with current soda consumption. Interventions to reduce consumption of soda in young Mexican‐American children should be considered. 相似文献
83.
Anna Aiello Ernesto Fattorusso Paolo Luciano Marialuisa Menna Marco A. Calzado Eduardo Muñoz Francesco Bonadies Marcella Guiso Maria Filomena Sanasi Gianfranco Cocco Rosario Nicoletti 《Bioorganic & medicinal chemistry》2010,18(2):719-727
The synthesis of analogues of aplidinone A (7), a prenylated quinone isolated from the Mediterranean ascidian Aplidium conicum, has been performed. This work not only allowed confirming the structural assignment of aplidinone A, previously made with the support of GIAO shielding calculations, but, above all, made a series of structurally related quinone derivatives (compounds 8–13 and the natural metabolite) available for a screening in vitro for cytotoxic and pro-apoptotic activity and for SAR studies. The study evidenced one of the synthetic analogues (11) as a potent cytotoxic and pro-apoptotic agent against several tumor cell lines which also inhibits the TNFα-induced NF-κB activation in a human leukemia T cell line. This exemplifies the potential of a natural product to qualify as lead structure for medicinal chemistry campaigns, affording simplified analogues with better bioactivity and easier to synthesize. 相似文献
84.
Marabotti A Herman P Staiano M Varriale A de Champdoré M Rossi M Gryczynski Z D'Auria S 《Proteins》2006,62(1):193-201
The effect of the pressure on the structure and stability of the D-Galactose/D-Glucose binding protein (GGBP) from Escherichia coli was studied by steady-state and time-resolved fluorescence spectroscopy, and the ability of glucose ligand to stabilize the GGBP structure was also investigated. Steady-state fluorescence experiments showed a marked quenching of fluorescence emission of GGBP in the absence of glucose. Instead, the presence of glucose seems to stabilize the structure of GGBP at low and moderate pressure values. Time-resolved fluorescence measurements showed that the GGBP taumean in the absence of glucose varies significantly up to 600 bar, while in the presence of the ligand it is almost unaffected by pressure increase up to 600 bar. The effect of the pressure on GGBP was also studied by molecular dynamics simulations. The simulation data support the spectroscopic results and confirm that the presence of glucose is able to contrast the negative effects of pressure on the protein structure. Taken together, the spectroscopic and computer simulation studies suggest that at pressure values up to 2000 bar the structure of GGBP in the absence of glucose remains folded, but a significant perturbation of the protein secondary structures can be detected. The binding of glucose reduces the negative effect of pressure on protein structure and confers protection from perturbation especially at moderate pressure values. 相似文献
85.
Augello C Gregorio V Bazan V Cammareri P Agnese V Cascio S Corsale S Calò V Gullo A Passantino R Gargano G Bruno L Rinaldi G Morello V Gerbino A Tomasino RM Macaluso M Surmacz E Russo A 《Journal of cellular physiology》2006,207(3):654-659
The putative role of TP53 and p16(INK4A) tumor suppressor genes and Ras oncogenes in the development and progression of salivary gland neoplasias was studied in 28 cases of pleomorphic adenomas (PA), 4 cases of cystic adenocarcinomas, and 1 case of carcinoma ex-PA. Genetic and epigenetic alterations in the above genes were analyzed by Polymerase Chain Reaction/Single Strand Conformational Polymorphism (PCR/SSCP) and sequencing and by Methylation Specific-PCR (MS-PCR). Mutations in TP53 were found in 14% (4/28) of PAs and in 60% (3/5) of carcinomas. Mutations in H-Ras and K-Ras were identified in 4% (1/28) and 7% (2/28) of PAs, respectively. Only 20% (1/5) of carcinomas screened displayed mutations in K-Ras. p16(INK4A) promoter hypermethylation was found in 14% (4/28) of PAs and 100% (5/5) carcinomas. All genetic and epigenetic alterations were detected exclusively in the epithelial and transitional tumor components, and were absent in the mesenchymal parts. Our analysis suggests that TP53 mutations and p16(INK4A) promoter methylation, but not alterations in the H-Ras and K-Ras genes, might be involved in the malignant progression of PA into carcinoma. 相似文献
86.
Protein and peptide arrays: recent trends and new directions 总被引:3,自引:0,他引:3
Microarrays of proteins and peptides make it possible the screening of thousands of binding events in a parallel and high throughput fashion; therefore they are emerging as a powerful tool for proteomics and clinical assays. The complex nature of Proteome, the wide dynamic range of protein concentration in real samples and the critical role of immobilized protein orientation must be taken into account to maximize the utility of protein microarrays. Immobilization strategy and designing of an ideal local chemical environment on the solid surface are both essential for the success of a protein microarray experiment. This review article will focus on protein and peptide arrays highlighting their technical challenges and presenting new directions by means of a set of selected recent applications. 相似文献
87.
Ribose phosphates are either synthesized through the oxidative branch of the pentose phosphate pathway or stem from the phosphorolytic cleavage of the N-glycosidic bond of ribonucleosides. The two major pentose phosphates, ribose-5-phosphate and ribose-1-phosphate, can be readily interconverted by phosphopentomutase. Ribose-5-phosphate is also the direct precursor of 5-phosphoribosyl-1-pyrophosphate, which is used for both de novo and salvage synthesis of nucleotides. On the other hand, the phosphorolysis of deoxyribonucleosides is the major source of deoxyribose phosphates. While the destiny of the nucleobase stemming from nucleoside phosphorolysis has been extensively investigated, the fate of the sugar moiety has been somehow neglected. However, extensive advances have been made in elucidating the pathways by which the pentose phosphates, arising from nucleoside phosphorolysis, are either recycled, without opening of their furanosidic ring, or catabolized as a carbon and energy source. Nevertheless, many aspects of pentose phosphate metabolism, and the possible involvement of these compounds in a number of cellular processes still remain obscure. The comprehension of the role played by pentose phosphates may be greatly facilitated by the knowledge of their steady-state intracellular levels and of their changes in response to variations of intra- and extracellular signals. 相似文献
88.
89.
D'Aniello S D'Aniello E Locascio A Memoli A Corrado M Russo MT Aniello F Fucci L Brown ER Branno M 《Differentiation; research in biological diversity》2006,74(5):222-234
The tadpole larvae prosencephalon of the ascidian Ciona intestinalis contains a single large ventricle, along the inner walls of which lie two sensory organs: the otolith (a gravity-sensing organ) and the ocellus (a photo-sensing organ composed of a single cup-shaped pigment cell, about 20 photoreceptor cells, and three lens cells). Comparison has been drawn between the morphology and physiology of photoreceptor cells in the ascidian ocellus and the vertebrate eye. The development of vertebrate and invertebrate eyes requires the activity of several conserved genes and it is regulated by precise expression patterns and cell fate decisions common to several species. We have isolated a Ciona homeobox gene (Ci-Rx) that belongs to the paired-like class of homeobox genes. Rx genes have been identified from a variety of organisms and have been demonstrated to have a role in vertebrate eye formation. Ci-Rx is expressed in the anterior neural plate in the middle tailbud stage and subsequently in the larval stage in the sensory vesicle around the ocellus. Loss of Ci-Rx function leads to an ocellus-less phenotype that shows a loss of photosensitive swimming behavior, suggesting the important role played by Ci-Rx in basal chordate photoreceptor cell differentiation and ocellus formation. Furthermore, studies on Ci-Rx regulatory elements electroporated into Ciona embryos using LacZ or GFP as reporter genes indicate the presence of Ci-Rx in pigment cells, photoreceptors, and neurons surrounding the sensory vesicle. In Ci-Rx knocked-down larvae, neither basal swimming activity nor shadow responses develop. Thus, Rx has a role not only in pigment cells and photoreceptor formation but also in the correct development of the neuronal circuit that controls larval photosensitivity and swimming behavior. The results suggest that a Ci-Rx "retinal" territory exists, which consists of pigment cells, photoreceptors, and neurons involved in transducing the photoreceptor signals. 相似文献
90.
Kurelac I Lang M Zuntini R Calabrese C Simone D Vicario S Santamaria M Attimonelli M Romeo G Gasparre G 《Biotechnology advances》2012,30(1):363-371
Mitochondrial DNA (mtDNA) mutations have been involved in disease, aging and cancer and furthermore exploited for evolutionary and forensic investigation. When investigating mtDNA mutations the peculiar aspects of mitochondrial genetics, such as heteroplasmy and threshold effect, require suitable approaches which must be sensitive enough to detect low-level heteroplasmy and, precise enough to quantify the exact mutational load. In order to establish the optimal approach for the evaluation of heteroplasmy, six methods were experimentally compared for their capacity to reveal and quantify mtDNA variants. Drawbacks and advantages of cloning, Fluorescent PCR (F-PCR), denaturing High Performance Liquid Chromatography (dHPLC), quantitative Real-Time PCR (qRTPCR), High Resolution Melting (HRM) and 454 pyrosequencing were determined. In particular, detection and quantification of a mutation in a difficult sequence context were investigated, through analysis of an insertion in a homopolymeric stretch (m.3571insC). 相似文献