we have developed a simple and precise paper chromatographic method for the determination of 4-hydroxy-3-methoxymandelic acid (vma) in urine. concentrations of vma in patients with neuroblastoma were increased in comparison to controls. the linearity was excellent in the concentration range tested. the within-assay coefficient of variation for control and patient urine was less than 2.2%. the r...

The regulator of ATPase of vacuoles and endosomes (RAVE) complex is implicated in vacuolar H(+)-translocating ATPase (V-ATPase) assembly and activity. In yeast, rav1 mutants exhibit a Vma(-) growth phenotype characteristic of loss of V-ATPase activity only at high temperature. Synthetic genetic analysis identified mutations that exhibit a full, temperature-independent Vma(-) growth defect when ...

Escherichia coli strain DIER was constructed for estrogen detection by inserting an estrogen-sensitive intein (VMA(ER) intein) into the specific site of the constitutively expressed chromosomal lacZ gene. This VMA(ER) intein was generated by replacing the endonuclease region of the Saccharomyces cerevisiae VMA intein with the estrogen binding region of the human estrogen receptor α (hERα). When...

called vanillylmandelic acid (VMA), in urine has recently come into use as a confirmatory test for pheochromocytoma (1-6). Armstrong and his associates (1, 2, 7) discovered that this phenolic acid occurred in small amounts in normal human urine and in elevated concentrations in pheochromocytoma. As a result of their observations (1, 2) and especially of those by others in related investigations...

To separately measure vanillylmandelic acid (VMA) and homovanillic acid (HVA) in urine, the sample is diluted 10-fold with 50 mmol/L phosphoric acid, then exactly 5 microL is injected directly onto a 50 X 4.6 mm column of Nucleosil 3C18. Samples can be injected at 5-min intervals because all peaks after these compounds of interest are washed away. VMA is eluted from the column after 2.8 min wit...

The aim of the study was to evaluate the influence of vitreomacular interface configuration on treatment outcomes after intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy for neovascular age-related macular degeneration (AMD).The Pubmed, Embase, and Cochrane Central Register of Controlled Trials databases were searched to identify relevant prospective or retrospective stud...

This study aims at finding alternative indigenous Sudanese material for concrete admixtures that are necessary casting in hot weather of the Sudan. The objective this to classify Gum Arabic (GA) namely, Acacia Senegal (known locally as Hashab Gum) viscosity modifying admixture (VMA) lowering powder content self compacting (SCC). methodology is based on European standards BS EN 934-2 & 480-1...

The determination of the two urinary catecholamine metabolites homovanillic acid (HVA) and vanillylmandelic acid (VMA) is of crucial importance for the diagnosis and follow-up of neuroblastoma (NB). The standard practice for their measurement requires the use of 24-hour collections that are time consuming and difficult to obtain. In this article, we directly demonstrate that 24-hour collections...

The urinary excretion of vanilmandelic acid (VMA), homovanillic acid (HVA), and parahydroxyphenylacetic acid (pHPAA) was measured in 55 children with meningomyelocoele selected at random. In 96% of the children the levels of one or other of these compounds was significantly raised above the normal, usually by a factor of about 3. High VMA levels usually meant high HVA levels but the values for ...