This review examines deoxyadenosylcobalamin (Ado-B12) biosynthesis, transport, use, and uneven distribution among living forms. We describe how genetic analysis of enteric bacteria has contributed to these issues. Two pathways for corrin ring formation have been found-an aerobic pathway (in P. denitrificans) and an anaerobic pathway (in P. shermanii and S. typhimurium)-that differ in the point ...

The erythrocyte membrane protein pattern of patients with megaloblastic anemia was determined by polyacrylamide gel electrophoresis in sodium dodecyl sulfate. In severe megaloblastic anemia, secondary either to folic acid or vitamin B12 deficiency, the erythrocyte membrane protein pattern was grossly abnormal, lacking bands 1, 2 (spectrin), and 3 and having several diffuse, faster migrating ban...

Although vitamin B12 can be assayed biologically with mice, chicks or rats, the microbiological method of assay is preferred since it is more rapid and economical. One serious shortcoming of many microbiological B12 assay procedures is the lack of specificity when crude materials are assayed. Crude materials can contain inhibitory or stimulatory factors which cause serious errors in assay resul...

40 41 The growing realization that electrical coupling is present in the mammalian brain has 42 sparked renewed interest in determining its functional significance and contrasting it with 43 chemical transmission. One question of interest is whether the two types of transmission 44 can be selectively regulated, e.g., if a cell makes both types of connections can electrical 45 transmission occur...

We are studying afferent transmission from a mechanoafferent, B21, to a follower, B8. During motor programs, afferent transmission is regulated so that it does not always occur. Afferent transmission is eliminated when spike propagation in B21 fails, i.e., when spike initiation is inhibited in one output region-B21's lateral process. Spike initiation in the lateral process is inhibited by the B...

Pitney, Beard, and Van Loon (2) and Ostrowski, Skarzynski, and Zak (3) reported in 1954 that vitamin B12 is bound primarily to a-globulin in normal serum. Pitney and his colleagues (2) also noted that p-globulin can bind B12 added in vitro, but they considered this as "free B12" because, unlike B12 bound to a-globulin, Euglena gracilis is able to utilize it without prior heat treatment. Miller ...

due to the complex assessment of young walnut cultivars (juglansregia l.) based on morphological traits, advance molecular tools have provided a new prospect for cultivar identification and dna fingerprinting. in this study, specific molecular keys were identified for 5 iranian walnut cultivars (juglansregia l.) using 30 ssr markers. the results showed that 5 ssr markers produced polymorphic ba...

Objective(s): Methamphetamine (METH) is a powerful stimulant drug that directly affects the brain and induces neurological deficits. B12 is a water-soluble vitamin (vit) that is reported to attenuate neuronal degeneration. The goal of the present study is to investigate the effect of vitamin B12 on METH’s neurodegenerative changes.Materials and Methods: Two groups of 6 animals received METH (10...