In contrast, all positions click here could be substituted to some extent when the library mutants were expressed from a multicopy plasmid. For the conserved quartet of charged residues Lys44-Asp71-Lys73-Asp76, a cysteine substitution was found to provide function at positions 71 and 76. A lower pK(a)

for both cysteine mutants supports a mechanism whereby the thiolate group of cysteine substitutes for the negatively charged aspartate side chain. The partial function mutants such as D71C and D76C exhibit reduced catalytic efficiency relative to wild type but nevertheless provide a rate enhancement of 15 orders of magnitude over the uncatalyzed rate indicating the catalytic proficiency of the enzyme is robust and tolerant of mutation.”
“Background. Though highly prevalent, the pathophysiology of orthostatic hypotension (OH), postprandial hypotension (PPH), and carotid sinus hypersensitivity (CSH) are rarely studied together. Therefore, we conducted such a comprehensive study focusing on the common role of the cardiovascular autonomic system. We hypothesized that in geriatric patients, OH, PPH, and CSH are manifestations of cardiovascular autonomic dysfunction and investigated state-of-the-art

cardiovascular autonomic function indices in a group of geriatric falls or syncope patients.

Methods. In a cross-sectional study of 203 consecutive eligible falls clinic patients, we compared heart rate variability (HRV), blood pressure variability (BPV), and baroreflex sensitivity (BRS)

as potential Quizartinib autonomic function determinants of the three different hypotensive syndromes.

Results. OH, PPH, and CSH were diagnosed in 53%, 57%, and 50% of the patients, respectively. In a population relevant for geriatric practice, we found no differences in HRV, BPV, and BRS between patients with and without OH, with and without PPH, and with and without CSH, respectively, nor between patients with and without falls, dizziness, or syncope as presenting symptom, respectively.

Conclusions. In geriatric patients with hypotensive syndromes, cardiovascular autonomic function as measured by HRV, BPV, and BRS is comparable to patients without such syndromes. These findings argue against a single or dominant etiological Selleckchem MK1775 factor, that is, cardiac autonomic dysfunction and underline the structured, broad, and multifactorial approach to elderly patients with falls and/or syncope as proposed in the current evidence-based syncope guidelines.”
“DNA-binding protein from starved cells (DPS), a mini-ferritin capable of self-assembling into a 12-meric nano-cage, was chosen as the basis for an alanine-shaving mutagenesis study to investigate the importance of key amino acid residues, located at symmetry-related protein-protein interfaces, in controlling protein stability and self-assembly.