In restoring a power system after a major disturbance, system operators often encounter an excessive standing phase angle difference (SPA) between two buses of a circuit breaker when a transmission line is energized and results in a loop closure. Under such a condition, there is high risk of damage to nearby generators and other equipments for the breaker/loop closure operation. Since the SPA v...

In this paper, we propose a simple but powerful on-line availability upgrade mechanism, Supplementary Parity Augmentations (SPA), to address the availability issue for parity-based RAID systems. The basic idea of SPA is to store and update the supplementary parity units on one or a few newly augmented spare disks for on-line RAID systems in the operational mode, thus achieving the goals of impr...

OBJECTIVES To investigate whether anti-Saccharomyces cerevisiae antibodies (ASCA), a marker for Crohn's disease (CD), are present in spondyloarthropathies (SpA) and in the subgroups ankylosing spondylitis (AS), undifferentiated SpA (uSpA), and psoriatic arthritis (PsA), in comparison with healthy and inflammatory controls (patients with rheumatoid arthritis (RA)). METHODS ASCA IgA and IgG lev...

Three Good Laboratory Practice safety studies were performed with intravenous injections of highly purified staphylococcal protein A (SPA) in cynomolgus monkeys, in support of a clinical development programme utilizing this protein as an immunomodulator. These studies established a no-observable-adverse-effect level (NOAEL) for up to 12 weekly doses of SPA, as well as toxicokinetic profiles for...

We constructed and analyzed a synthetic poly(A) (SPA) site that was based on the highly efficient poly(A) signal of the rabbit beta-globin gene. By use of the SPA, we demonstrate that the minimum sequences required for efficient polyadenylation are the AATAAA sequence and a GT/T-rich sequence with the correct spacing of 22-23 nucleotides between them. When placed downstream of the poly(A) site ...

SPA-1 is a principal Rap1 GTPase-activating protein in the hematopoietic progenitors and peripheral T cells, and SPA-1-deficient mice develop a spectrum of myeloproliferative stem cell disorders of late onset. In the present study, we show that SPA-1-deficient mice develop age-dependent T cell unresponsiveness preceding the myeloid disorders, whereas the T cell numbers remained unchanged. Progr...

Objective(s): Staphylococcus aureus is an important bacterial pathogen responsible for a variety numbers of nosocomial and community acquired infections. Biofilm formation is regarded as an important factor in the establishment of S. aureus infection. The contribution of the genetic background of S. aureus to biofilm formation is poorly understood. The aim of the present work was to genotype S....

Staphylococcal protein A (SpA) is anchored to the cell wall envelope of Staphylococcus aureus by sortase A, which links the threonyl (T) of its C-terminal LPXTG motif to peptidoglycan cross-bridges (i.e., Gly5). SpA binds the Fcγ domains of IgG and protects staphylococci from opsonophagocytic clearance. Moreover, SpA cross-links B-cell receptors to modify host adaptive immune responses. The mec...

Staphylococcal protein A (SpA) is an important virulence factor from Staphylococcus aureus responsible for the bacterium's evasion of the host immune system. SpA includes five small three-helix-bundle domains that can each bind with high affinity to many host proteins such as antibodies. The interaction between a SpA domain and the Fc fragment of IgG was partially elucidated previously in the c...

The gene coding for protein A (spa) of Staphylococcus aureus 8325-4 has been inactivated by substituting part of the spa coding sequence for a DNA fragment specifying resistance to ethidium bromide. The in vitro-constructed spa::EtBrr substitution mutation was introduced into the S. aureus chromosome by recombinational allele replacement. Southern blot hybridization showed that the in vitro-con...