Inorganic Phosphate

The spatial and temporal coordination of the many events required for osteogenic cells to create a
mineralized matrix are only partially understood. The complexity of this process, and the nature of the final product,
demand that these cells havemechanisms to carefullymonitor events in the extracellular environment and have the ability
to respond through cellular and molecular changes. The generation of inorganic phosphate during the process of
differentiation may be one such signal. In addition to the requirement of inorganic phosphate as a component of
hydroxyapatite mineral, Ca10(PO4)6(OH)2, a number of studies have also suggested it is required in the events preceding
mineralization. However, contrasting results, physiological relevance, and the lack of a clearmechanism(s) have created
some debate as to the significance of elevated phosphate in the differentiation process.More recently, a number of studies
have begun to shed light on possible cellular andmolecular consequences of elevated intracellular inorganic phosphate.
These results suggest amodel inwhich the generation of inorganic phosphate during osteoblast differentiationmay in and
of itself represent a signal capable of facilitating the temporal coordination of expression and regulation ofmultiple factors
necessary for mineralization. The regulation of protein function and gene expression by elevated inorganic phosphate
during osteoblast differentiation may represent a mechanism by which mineralizing cells monitor and respond to the
changing extracellular environment. J. Cell. Biochem. 90: 234–243, 2003. Published 2003 Wiley-Liss, Inc.
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Key words: inorganic phosphate; osteoblast differentiation; calcium; osteopontin; alkaline phosphatase

The carp ponds of Deroua station (Beni Mellal, Centre of Morocco) receive a large quantity of fertilizers, particularly urea and triple super phosphate during the entire period of culture. Only a small part of that is necessary to promote an adequate development of phytoplankton, the base of the food chain. A large part of the phosphate added to the ponds is stocked in pond soils and can be released under specific conditions. Although some phosphate is necessary for the development of aquatic populations, too large of an input causes problems. Therefore, knowledge of the external load and the mobility of the internal pool is essential for the purpose of management against eutrophication. In order to assess the inorganic and organic fractions of phosphate present in sediments, different methods of P fractionation were compared. The methods do not give the same results. In the Deroua sediments, calcium-bound phosphate represents the major part of total phosphate between 86% and 91% according to the different methods. The org-Phosphate represents a small part and varies considerably depending on the different methods between 0.87 and 5%. EDTA extractions (Golterman, 1996) have an advantage over other methods such as the Sedex, the Hieltjes & Lijklema and the Bonzongo procedures.

Pulmonary tuberculosis (PTB) is still a very common cause of morbidity and mortality around the globe and the disorder of calcium and inorganic phosphate metabolism has been poorly associated with the infection. This study was aimed at assessing the total serum calcium and inorganic phosphate levels in PTB patients