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A A Campbell

Publications and source records attributed to A A Campbell.

14 recordsLinked to original sources
PubMed1991

Physical chemical studies of calcium oxalate crystallization.

The physical chemical approach to the investigation of the calcium oxalate (CaOx) crystallization and urolith formation is the systematic examination of the various aspects of mineral precipitation and growth in pure solution, in the presence of individual urinary components, and in whole urine media. Recent experimental studies have indicated that while small urinary ions such as citrate, magnesium, and phosphocitrate retard the mineralization rate of CaOx, urinary macromolecules may act either as inhibitors of growth or promoters of nucleation. Some CaOx mineralization inhibitors have also been found to influence the growth mechanism of the phase and its flocculation properties. Therefore, urinary macromolecules that are adsorbed on the mineralizing crystals and incorporated into the developing stone may play a significant role in urolithiasis.

Calcium Oxalate↗
PubMed1991

The response of American women to the threat of AIDS and other sexually transmitted diseases.

Using data from the National Survey of Family Growth, we observe that large numbers of American women say that they are responding to the rising danger of AIDS and other sexually transmitted diseases. Among the changes reported in the 1988 National Survey of Family Growth are use of condoms, sexual relations with fewer partners, reduced frequency of sexual intercourse, changes in specific sexual activities, and avoidance of sex with unknown men, bisexual men, and intravenous drug users. Interviews with a sample of the 51 million sexually active women aged 15-44 in the United States show that 28% report either that they have adopted less hazardous sexual practices or that their partners have used condoms to prevent disease. Among women exposed to higher risk of disease, the response is even greater: among unmarried women with five or more lifetime partners, 65% report modified behavior or condom use. Most of these changes occurred after the women heard of AIDS. However, there are still many women who report doing nothing to protect themselves against infection despite sexual and contraceptive behavior that appears to put them at high risk.

Acquired Immunodeficiency Syndrome↗
PubMed1989

The dual role of polyelectrolytes and proteins as mineralization promoters and inhibitors of calcium oxalate monohydrate.

Polyelectrolytes and protein molecules appear to be able to act not only as crystallization inhibitors when present in solution, but also as promoters of crystal growth when immobilized onto surfaces. Because this is especially relevant for systems in which heterogeneous nucleation can occur, the influence of poly-L-glutamic (PGlu) acid, poly-L-aspartic (PAsp) acid, and human serum albumin (HSA) on the nucleation and growth inhibition of calcium oxalate monohydrate (COM) was studied using the Constant Composition (CC) kinetics technique. The overgrowth of COM on hydroxyapatite (HAP) seed crystals pretreated with HSA was also investigated. Pronounced differences in inhibiting and nucleating potential were found for the various additives. HSA, a relatively poor growth inhibitor when present in solution, was found to nucleate very regular, hexagonal COM crystals when immobilized on a surface and to enhance the overgrowth of COM when adsorbed on HAP surfaces.

Calcium Oxalate↗