Calcifications enhancement

ARJMANDI B H, KHALIL D A and HOLLIS B w (2000) Ipiiflavone, a synthetic phytoestrogen, enhances intestinal calcium transport in vitro. Calcif Tissue Int 67, 225-29. 

High phosphate diets cause decreased Ca absorption, secondary hyperparathyroidism, accelerated bone resorption and soft tissue calcification in some animals, but not in normal humans. Although phosphates may decrease Ca absorption in man at very high (> 2000 mg/day) Ca intakes, they do not do so at more moderate Ca levels and enhance Ca absorption at very low levels (< 500 mg/day). Phosphates increase renal tubular reabsorption and net retention of Ca. At low Ca intakes, phosphates stimulate parathyroid hormone (PTH) secretion without causing net bone resorption. 

Yamaguchi, M. and Matsui, T. (1997). Zinc enhancement of 17beta-estradiol s anabolic effect in osteoblastic MC3T3-E1 cells. Calcif. Tissue Int. 60, 527-532. 

Parhami, F., Tintut, Y., Ballard, A., Fogelman, A. M., and Demer, L. L. 2001. Leptin enhances the calcification of vascular cells artery wall as a target of leptin. Circ. Res. 88 954—960. 

A CT scan may show calcification and non-specific hypo- or hyperdensity, while an enhanced scan is likely to show the dilated vessels of large malformations. Magnetic resonance imaging is more sensitive, showing evidence of old hemorrhage and vascular... 

Chalker, B.E. and Taylor, D.L., 1975. Light enhanced calcification, and the role of oxidative phosphorylation in calcification of the coral Acropora cervicornis. Proc. R. Soc. London, Ser. B., 190 323—331. 

Nucleation of calcium phosphate precipitation within the matrix vesicles is mediated by phosphatidylserine, which comprises about 8% of the phospholipids of the inner cytosolic membrane surface (Fig. 9.5a). Calbindin in the vesicle (Fig. 9.5b) may also contribute. Rapid mineral growth within the vesicle keeps the concentration of dissolved calcium and inorganic phosphate ions so low that additional Ca2+ and Pi ions spontaneously enter from the extracellular fluid via their respective transporters. Attached type II and type X collagens from cartilage in the growth plate enhance calcium ion transport and calcification during endochondral ossification (Fig. 9.5b). 

Congestive heart failure is common and is related to fluid overload, hypertension, or atherosclerosis. Some workers have postulated a uremic cardiomyopathy. The enhancement by parathormone of cellular calcium uptake may contribute to myocardial calcification, degeneration, and fibrosis (M26). There is a higher incidence of calcification of the aortic and mitral valves, as well as of visceral and peripheral arteries in association with uremic hyperparathyroidism (M13). In addition to PTH, middle molecules (B19), phenols (L3), guanidino-succinic acid (K5), or cobalt (P6) may contribute to the observed cardiotoxicity in vitro of uremic serum. 

To the best of our knowledge, only a few studies have attempted to prevent the calcification of HEMA-based hydrogels. It has been reported that introduction of carboxylate anions can either prevent or enhance calcification. Cemy et al. (21) found that copolymers of HEMA with 4 wt% methaciylic acid (MAAc) did not calcify under subcutaneous implantation in a rat for 14 months. A similar result was also observed after the implantation of HEMA/MAAc copolymers in the animal urinary tract (22). Other studies carried out in vitro showed that the presence of carboxylate anions significantly reduced the deposition of calcium phosphate (23) and calcium oxalate (24) on acrylic polymers and certain biopolymers. These findings obviously suggest an inhibitory effect of carboxylate anions on calcification. However, by contrast,... 

Enhanced calcification, i. e. fast biomineraUza-tion rates, in foraminifer tests could be a direct consequence of higher carbonate supersaturation (Lohmann 1995 Barker Elderfield 2002 Bijma et al. 2002). Since CO2 is less soluble in warmer waters, calcium carbonate supersaturation increases from the poles to the tropics (Buddemeier Eautin... 

Rey C, Collins B, Goehl T, Dickson IR, Glimcher MJ (1989) The carbonate enviromnent in bone mineral A resolution-enhanced Fourier transform infrared spectroscopy study. Calcif Tissue Inti 45 157-164 Roeder PL, MacArthur D, Ma XP, Palmer GR (1987) Cathodoluminescence and microprobe study of rare-earth elements in apatites. Am Mineral 72 801-811 Ronsbo JG (1989) Coupled substitution involving REEs and Na and Si in apatites in alkaline rocks from the Illimaussaq intmsions. South Greenland, and the petrological implications. Am Mineral 74 896-901 Rouse RC, Dunn PJ (1982) A contribution to the crystal chemistry of ellestadite and the sihcate srrlfate apatites. Am Mineral 67 90-96... 

Rey C, Shimizu M, Collins B, Glimcher MJ (1991c). Resolution-enhanced Fourier transform infrared spectroscopy study of the environment of phosphate ion in the early deposits of a solid phase of calcium phosphate in bone and enamel and their evolution with age 2. Investigations in the V3 PO4 domain. Calcif Tissue Inti 49 383-388... 

On CT, a typical hemangioma will be seen as a mass with lower attenuation than the adjacent liver. After contrast injection it will show a peripheral enhancement followed by centripetal filling on late images. Some necrotic areas or calcifications might not enhance. More than 50% of hemangiomas will contain calcifications on CT. 

US will reveal pancreatic cysts. On CT these cysts will have lower attenuation than the normal pancreatic parenchyma, and calcifications might be seen with unenhanced and enhanced CT (Choyke et al. 1990 Hough et al. 1994). 

On CT, an area of low attenuation with calcifications and disruption of the normal contour can be identified. On enhanced CT, the tumor will show a momentary enhancement that will be higher in the arterial phase compared with the portal venous phase. 

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