BACKGROUND Glycine N-methyltransferase is an enzyme overexpressed in some neoplastic tissues. It catalyses the methylation of glycine using S-adenosyl methionine (SAM or AdoMet) as substrate. SAM is involved in a great variety of biochemical processes, including transmethylation reactions. Thus, [11C]SAM could be used to evaluate transmethylation activity in tumours. The only method reported fo...

Severe acute malnutrition (SAM) is a common condition that kills children and intellectually maims those who survive. Close to 20 million children under the age of 5 years suffer from SAM globally, and about 1 million of them die each year. Much of this burden takes place in Asia. Six countries in Asia together have more than 12 million children suffering from SAM: 0.6 million in Afghanistan, 0...

PURPOSE To investigate age-related changes in the retinal pigment epithelium (RPE), Bruch's membrane, and choriocapillaris in the senescence-accelerated mouse (SAM). METHODS The external and eyecup features and light and electron microscopic findings were examined in three male and two female mice of a senescence-prone mouse strain (SAM P(8)) monthly for 12 months. These results were compared...

PURPOSE To investigate senescent evidence in corneal endothelial cells (CECs) of the senescence-accelerated mouse (SAM), which is considered a suitable animal model for the further study of the senescent mechanism in CECs. METHODS Thirty-six male mice from a senescence resistant mouse strain (SAM R1) and a senescence-prone strain (SAM P8) at various ages (1, 6, and 12 months) were analyzed in...

This paper describes an experimentally simple system for measuring rates of electron transport across organic thin films having a range of molecular structures. The system uses a metal--insulator--metal junction based on self-assembled monolayers (SAMs); it is particularly easy to assemble. The junction consists of a SAM supported on a silver film (Ag-SAM(1)) in contact with a second SAM suppor...

A fundamental question in developmental biology is how spatial patterns are self-organized from homogeneous structures. In 1952, Turing proposed the reaction-diffusion model in order to explain this issue. Experimental evidence of reaction-diffusion patterns in living organisms was first provided by the pigmentation pattern on the skin of fishes in 1995. However, whether or not this mechanism p...

SAM2 serves as a methyl donor in many transmethylation reactions involving a variety of methyl acceptor molecules such as proteins, lipids, polysaccharides, and nucleic acids. In addition, SAM is a precursor in the synthesis of polyamines and ethylene (8). It has been suggested that the dynamic equilibrium between polyamines and ethylene in cells is regulated through the availability of SAM (1,...

OBJECTIVES The purpose of this study was to determine whether the dynamic cause for mitral systolic anterior motion (SAM) is a Venturi or a flow drag (pushing) mechanism. BACKGROUND In obstructive hypertrophic cardiomyopathy (HCM), if SAM were caused by the Venturi mechanism, high flow velocity in the left ventricular outflow tract (LVOT) should be found at the time of SAM onset. However, if ...

Recent studies suggest that an auditory nonlinearity converts second-order sinusoidal amplitude modulation (SAM) (i.e., modulation of SAM depth) into a first-order SAM component, which contributes to the perception of second-order SAM. However, conversion may also occur in other ways such as cochlear filtering. The present experiments explored the source of the first-order SAM component by inve...