Abstract-Although central pulse pressure (PPc) is strongly related to central mean arterial pressure (MAPc), PPc predicts cardiovascular outcomes beyond MAPc. Whether modifiable risk factors for hypertension contribute to PPc and its determinants, independent of MAPc, is uncertain. In 635 randomly recruited participants, we assessed the independent relationship between 24-hour urinary sodium (Na ϩ ) or potassium (K ϩ ) excretion and brachial artery PP (in office or 24-hour; nϭ487), PPc, the forward (P1) and augmented (Paug) pressure wave components of PPc, central augmentation index, and determinants of central pressure waves, including aortic pulse wave velocity, effective reflecting distance, and reflective wave transit time. Central dynamics were determined using applanation tonometry of the carotid, femoral, and radial arteries. With adjustments for potential confounders, urinary Na ϩ /K ϩ was independently associated with in-office, central, and 24-hour PP, as well as Paug, P1, and central augmentation index (PϽ0.05 to PϽ0.005). With further adjustments for MAPc (or diastolic BP), urinary Na ϩ /K ϩ was independently associated with PPc, 24-hour PP, Paug, P1, and central augmentation index (PϽ0.05 to Pϭ0.005) but not with in-office PP, pulse wave velocity, effective reflecting distance, or reflective wave transit time. In conclusion, in a population of African ancestry, urinary salt excretion is independently related to central and 24-hour PP independent of MAPc or diastolic BP, effects that are attributed to increases in both P1 and Paug but not to pulse wave velocity. Hence, modifying salt intake could influence cardiovascular risk through effects on 24-hour and central PPs, as well as P1 and Paug, independent of steady-state pressure (MAP or diastolic BP) or pulse wave velocity. (Hypertension. 2010;56:584-590.) Key Words: pulse pressure Ⅲ arterial stiffness Ⅲ central blood pressure Ⅲ salt intake P ulse pressure (PP) predicts cardiovascular outcomes beyond other measures of blood pressure (BP), including measures of steady-state pressure, such as mean arterial pressure (MAP). [1][2][3][4][5][6][7][8][9][10][11][12][13][14] Moreover, central PP may be more closely associated with cardiovascular outcomes than peripheral PP. [15][16][17][18][19] Thus, contemporary notions of the adverse actions of BP are viewed in terms of steady-state effects, indexed by MAP, and dynamic or pulsatile effects, indexed by PP, with central PP receiving the most attention. The effects of PP independent of MAP on cardiovascular outcomes 1-14 are particularly impressive considering the close relationship between MAP and PP. Developing strategies that decrease PP, particularly central PP, without necessarily influencing MAP, is, therefore, of considerable interest, and in this regard understanding the mechanisms responsible for these changes is of importance. Although aging has been identified as the major determinant of PP, with increases in both the augmented and the forward pressure wave contributing to central PP, 20 -23 the im...

The Wollemi pine, Wollemia nobilis (Araucariaceae), was discovered in 1994 as the only extant member of the genus, previously known only from the fossil record. With fewer than 100 trees known from an inaccessible canyon in southeastern Australia, it is one of the most endangered tree species in the world. We conducted a comparative population genetic survey at allozyme, amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) loci in W. nobilis, Araucaria cunninghamii and Agathis robusta - representatives of the two sister genera. No polymorphism was detected at 13 allozyme loci, more than 800 AFLP loci or the 20 SSR loci screened in W. nobilis. In Ag. robusta only one of 12 allozyme loci, five of 800 AFLP loci and none of the 15 SSR loci were variable. For A. cunninghamii, 10 of > 800 AFLP loci and five of 20 SSR loci were variable. Thus low genetic diversity characterizes all three species. While not ruling out the existence of genetic variation, we conclude that genetic diversity is exceptionally low in the Wollemi pine. To our knowledge this is the most extreme case known in plants. We conclude that the combination of small population effects, clonality and below-average genetic variation in the family are probable contributing factors to the low diversity. The exceptionally low genetic diversity of the Wollemi pine, combined with its known susceptibility to exotic fungal pathogens, reinforces current management policies of strict control of access to the pines and secrecy of the pine locations.

Both large and small scale migrations of Helicoverpa armigera Hü bner in Australia were investigated using AMOVA analysis and genetic assignment tests. Five microsatellite loci were screened across 3142 individuals from 16 localities in eight major cotton and grain growing regions within Australia, over a 38-month period