giardia lamblia is one of the most common intestinal protozoan parasites infecting human in the world. the goal of this study was searching for in-vitro effect of folic acid and cobalamin on adhesion and growth of g. lamblia as two important mechanisms in the pathogenesis in tyi-s-33 medium. g. lamblia trophozoites were obtained by in- vitro excystation procedure. three groups of giardia tropho...

Cobalamin is an essential cofactor for enzyme systems, and adequate amounts are required for nucleic acid synthesis and hematopoiesis. The 2 most important reactions involving cobalamin are the conversion of methylmalonyl-coenzyme A to succinylcoenzyme A and the remethylation of homocysteine. Cobalamin deficiency leads to decreased activity of these enzyme systems, resulting in increased concen...

BACKGROUND Indian Asian men residing in the United Kingdom have a higher prevalence of hyperhomocysteinemia than do their European counterparts. This has been largely attributed to dietary deficiencies in cobalamin associated with vegetarianism among these Indian Asians. OBJECTIVE We aimed to ascertain the prevalence of folate and cobalamin deficiencies and hyperhomocysteinemia in Bangladesh....

Southern Ocean primary productivity plays a key role in global ocean biogeochemistry and climate. At the Southern Ocean sea ice edge in coastal McMurdo Sound, we observed simultaneous cobalamin and iron limitation of surface water phytoplankton communities in late Austral summer. Cobalamin is produced only by bacteria and archaea, suggesting phytoplankton-bacterial interactions must play a role...

BACKGROUND Lack of cobalamin may lead to neurologic disorders, which have been reported in strict vegetarians. OBJECTIVE The objective of this study was to investigate whether cognitive functioning is affected in adolescents (aged 10-16 y) with marginal cobalamin status as a result of being fed a macrobiotic diet up to an average age of 6 y. DESIGN Data on dietary intake, psychological test...

Candida utilis has been shown to contain 4.7 pmol of cobalamin per g of wet cell paste. Purification of the cobalamin showed it to be a mixture of methylcobalamin and adenosylcobalamin. Two cobalamin-dependent enzyme systems have been found in the yeast: methylcobalamin-dependent methionine biosynthesis and leucine 2,3-aminomutase. The cobalamin extracted from the yeast is as effective as authe...

Fat digestibility is decreased in old cats for unknown reasons. Subclinical gastrointestinal diseases and pancreatic dysfunction, both related to ageing, can affect food digestibility. The aim of the present study was to elucidate the prevalence of subnormal cobalamin concentration and pancreatic disease in old cats and study the relationship between both markers and fat digestibility. A total ...

Adipose tissue plays important roles in regulating carbohydrate and lipid homeostasis, but less is known about the regulation of amino acid metabolism in adipocytes. Here we applied isotope tracing to pre-adipocytes and differentiated adipocytes to quantify the contributions of different substrates to tricarboxylic acid (TCA) metabolism and lipogenesis. In contrast to proliferating cells, which...

Earlier work in this Laboratory has established conditions for the formation of methionine, from homocysteine plus serine or formaldehyde, by soluble enzyme systems extracted from Eseherichia coli. A cofactor of the folic acid group* is essential, and with E. coli PA 15 an extract of the heated organisms, H4PtG3 and its N5and N'0-formyl derivatives are all effective. H4PtG inhibits competitivel...