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91.
Sacha?AFT?van Hijum Anne?de Jong Richard?JS?Baerends Harma?A?Karsens Naomi?E?Kramer Rasmus?Larsen Chris?D?den Hengst Casper?J?Albers Jan?Kok Oscar?P?KuipersEmail author 《Genome biology》2005,6(4):P4
Background
In research laboratories using DNA-microarrays, usually a number of researchers perform experiments, each generating possible sources of error. There is a need for a quick and robust method to assess data quality and sources of errors in DNA-microarray experiments. To this end, a novel and cost-effective validation scheme was devised, implemented, and employed. 相似文献92.
Albala JS Franke K McConnell IR Pak KL Folta PA Rubinfeld B Davies AH Lennon GG Clark R 《Journal of cellular biochemistry》2000,80(2):187-191
The development of high-throughput methods for gene discovery has paved the way for the design of new strategies for genome-scale protein analysis. Lawrence Livermore National Laboratory and Onyx Pharmaceuticals, Inc., have produced an automatable system for the expression and purification of large numbers of proteins encoded by cDNA clones from the IMAGE (Integrated Molecular Analysis of Genomes and Their Expression) collection. This high-throughput protein expression system has been developed for the analysis of the human proteome, the protein equivalent of the human genome, comprising the translated products of all expressed genes. Functional and structural analysis of novel genes identified by EST (Expressed Sequence Tag) sequencing and the Human Genome Project will be greatly advanced by the application of this high-throughput expression system for protein production. A prototype was designed to demonstrate the feasibility of our approach. Using a PCR-based strategy, 72 unique IMAGE cDNA clones have been used to create an array of recombinant baculoviruses in a 96-well microtiter plate format. Forty-two percent of these cDNAs successfully produced soluble, recombinant protein. All of the steps in this process, from PCR to protein production, were performed in 96-well microtiter plates, and are thus amenable to automation. Each recombinant protein was engineered to incorporate an epitope tag at the amino terminal end to allow for immunoaffinity purification. Proteins expressed from this system are currently being analyzed for functional and biochemical properties. 相似文献
93.
Albala K 《Studies in History and Philosophy of Science Part C: Studies in History and Philosophy of Biological and Biomedical Sciences》2012,43(2):323-328
Despite major theoretical shifts in early modern nutritional theory, from humoralism to chemical and mechanical systems, the form and structure of convalescent cookery remained remarkably constant throughout the era and to a large extent even down to the present. In medical texts, cookbooks and in the popular imagination convalescent food generally mirrored food for infants, being soft and bland, based on dairy and grains, as well as foods considered highly nutritious yet easy to digest like concentrated broths. This article traces the development of ideas about convalescent food and how little they change over time. 相似文献
94.
José Manuel Matamala Carolina Nuñez Renato J. Verdugo Lydia Lera Hugo Sánchez Cecilia Albala 《Somatosensory & motor research》2014,31(3):136-140
Introduction: Vitamin B12 deficiency causes neurologic and psychiatric disease, especially in older adults. Subacute combined degeneration is characterized by damage to the posterior and lateral spinal cord affecting the corticospinal tract.Objective: To test corticospinal tract projections using motor evoked potentials (MEPs) by transcranial magnetic stimulation (TMS) in asymptomatic older adults with low vitamin B12 (B12) levels.Methods: Cross-sectional study of 53 healthy older adults (>70 years). MEPs were recorded in the abductor pollicis brevis and tibialis anterior muscles, at rest and during slight tonic contraction. Central motor conduction time (CMCT) was derived from the latency of MEPs and peripheral motor conduction time (PMCT). Neurophysiological variables were analyzed statistically according to B12 status.Results: Median age was 74.3?±?3.6 years (58.5% women). Twenty-six out of the 53 subjects had low vitamin B12 levels (B12?221?pmol/l). MEPs were recorded for all subjects in upper and lower extremities. There were no significant differences in either latency or amplitude of MEPs and CMCT between low and normal B12 groups. There was a significant PMCT delay in the lower extremities in the low B12 group (p?=?0.014).Conclusions: No subclinical abnormality of the corticospinal tract is detected in asymptomatic B12-deficient older adults. The peripheral nervous system appears to be more vulnerable to damage attributable to this vitamin deficit. The neurophysiological evaluation of asymptomatic older adults with lower B12 levels should be focused mainly in peripheral nervous system evaluation. 相似文献
95.
MG Oliveira Alves CFL Carta M-E Padín-Iruegas M Pérez-Sayáns JM Suarez-Peñaranda JS Issa 《Biotechnic & histochemistry》2016,91(4):263-268
We investigated the gene and protein expressions of V-type ATPase protein subunit C1 (ATP6V1C1) in cases of oral squamous cell carcinoma (OSCC) and contralateral normal mucosa in smokers, nonsmokers and former smokers. Subjects were separated into five groups of 15: group 1, smokers with OSCC; group 2, normal contralateral mucosa of OSCC patients; group 3, chronic smokers; group 4, former smokers who had stopped smoking 1 year earlier; group 5, individuals who had never smoked. Exfoliative cytology specimens from oral mucosa of smokers, former smokers and nonsmokers showed normal gene and protein expression. We found significantly greater gene expression in the OSCC group than in the nonsmoker groups. No difference in gene expression was observed between normal contralateral mucosa and nonsmoker groups, smoker and nonsmoker groups or former smoker and nonsmoker groups. We observed intense immunostaining for ATP6V1C1 protein in all cases of OSCC and weak or no staining in smoker, former smoker and nonsmoker groups. Significantly greater expression of ATP6V1C1 protein was observed in the OSCC group compared to the other groups, which supports the role of ATP6V1C1 in effecting changes associated with oral cancer. Analysis of the mucosae of chronic smokers, former smokers and the normal contralateral mucosa of patients with OSCC showed unaltered ATP6V1C1 gene and protein expression. Early stages of carcinogenesis, represented by altered epithelium of chronic smokers, had neither gene nor protein alterations as seen in OSCC. Therefore, we infer that the changes in ATP6V1C1 occur during later stages of carcinogenesis. Our preliminary study provides a basis for future studies of using ATP6V1C1 levels for detecting early stage OSCC. 相似文献
96.
Liane FM Finotelo Paulo JS Amaral Julio C Pieczarka Edivaldo HC de Oliveira Alcides Pissinati Michaela Neusser Stephan Müller Cleusa Y Nagamachi 《BMC evolutionary biology》2010,10(1):189
Background
The New World monkey (Platyrrhini) subfamily Pitheciinae is represented by the genera Pithecia, Chiropotes and Cacajao. In this work we studied the karyotypes of Pithecia irrorata (2n = 48) and Cacajao calvus rubicundus (2n = 45 in males and 2n = 46 in females) by G- and C-banding, NOR staining and chromosome painting using human and Saguinus oedipus whole chromosome probes. The karyotypes of both species were compared with each other and with Chiropotes utahicki (2n = 54) from the literature. 相似文献97.
Cecilia Albala Jos L. Santos Mariana Cifuentes Ana C. Villarroel Lydia Lera Claudio Liberman Brbara Angel Francisco Prez‐Bravo 《Obesity (Silver Spring, Md.)》2004,12(2):340-345
Objective: To assess the association between the Ala54Thr genetic polymorphism of the fatty acid‐binding protein 2 (FABP2) gene with insulin resistance and obesity. Research Methods and Procedures: According to a sampling scheme based on BMI, 33 adult obese women (BMI ≥ 30) and 30 adult normal‐weight women (BMI > 18.5 and < 25 kg/m2) were recruited for this study. Women with chronic inflammatory diseases or acute pathology were excluded. Glucose, insulin, leptin, lipids, and tumor necrosis factor α (TNFα) were measured in fasting plasma samples. Insulin resistance was estimated through the homeostasis model assessment for insulin resistance method. The Ala54Thr allelic variant was determined by polymerase chain reaction, followed by restriction fragment‐length polymorphism analysis. Results: The Thr54 allele was more frequent in obese than in nonobese women (47.0% vs. 31.7; p = 0.08). Among obese women, higher TNFα concentrations were found when comparing the Thr54/Thr54 genotype (30.0 ± 7.1 pg/mL) with either the Ala54/Thr54 genotype (21.2 ± 8.4 pg/mL) or the Ala54/Ala44 genotype (20.1 ± 7.0 pg/mL) (p < 0.05). In addition, higher fasting plasma insulin and leptin levels were found among Thr54/Thr54 homozygotes compared with the other genotypes (p < 0.05). Discussion: Our results suggest that the Ala54Thr polymorphism of the FABP2 gene is associated with obesity and insulin resistance. The effect of this polymorphism might be mediated by elevated production of TNFα. 相似文献
98.
99.
Shechinah Felice Choragudi Ganesh Kumar Veeramachaneni BV Raman Bondili JS 《Bioinformation》2014,10(8):507-511
Endo- β-N-acetylgucosaminidases (ENGases) are the enzymes that catalyze both hydrolysis and
transglycosylation reactions. It is of interest to study ENGases because of their ability to synthesize glycopeptides.
Homology models of Human, Arabidopsis thaliana and Sorghum ENGases were developed and their active sites
marked based on information available from Arthrobacter protophormiae (PDB ID: 3FHQ) ENGase. Further, these
models were docked with the natural substrate GlcNAc-Asn and the inhibitor Man3GlcNAc-thiazoline. The catalytic
triad of Asn, Glu and Tyr (N171, E173 and Y205 of bacteria) were found to be conserved across the phyla. The crucial
Y299F mutation showing 3 times higher transglycosylation activity than in wild type Endo-A is known. The hydrolytic
activity remained unchanged in bacteria, while the transglycosylation activity increased. This Y to F change is found
to be naturally evolved and should be attributing higher transglycosylation rates in human and Arabidopsis thaliana
ENGases. Ligand interactions Ligplots revealed the interaction of amino acids with hydrophobic side chains and polar
uncharged side chain amino acids. Thus, structure based molecular model-ligand interactions provide insights into
the catalytic mechanism of ENGases and assist in the rational engineering of ENGases. 相似文献
100.