Accelerated apoptosis in SLE neutrophils cultured with anti-dsDNA antibody isolated from SLE patient serum: a pilot study.

Increased numbers of apoptotic neutrophils are found in SLE, related to disease activity and levels of anti-dsDNA antibody. The mechanism of increased apoptosis is not clear, but anti-dsDNA antibody has been shown to induce apoptosis in neutrophils from normal subjects and in certain cell lines. In this study, polyclonal anti-dsDNA antibody was isolated from the serum of a patient with active SLE, and was shown to substantially accelerate apoptosis in neutrophils from SLE patients as compared with neutrophils from healthy control or rheumatoid arthritis subjects.

Distinctive effects of G-CSF, GM-CSF and TNFalpha on neutrophil apoptosis in systemic lupus erythematosus.

OBJECTIVE: To investigate the influence of culture with G-CSF GM-CSF and TNFalpha on neutrophil apoptosis, comparing neutrophils from SLE patients with rheumatoid arthritis (RA) patients and healthy control subjects. METHODS: Neutrophils were isolated from SLE (n= 10), RA (n= 10) and healthy control subjects (n= 10), and cultured with two different concentrations of G-CSF, GM-CSF and TNFalpha. Proportion of apoptotic neutrophils at T=0, T=2hrs and T=24hrs was measured using FITC-labelled annexinV and flow cytometry. RESULTS: Significantly more neutrophils were apoptotic at T=0 in the SLE subjects than in the other groups (median, range--Control 3.5% (0.3-7.9) SLE 9.5% (2.9-29.1) RA 3.0% (0.4-23.0) p

Do pigs form preferential associations?

This investigation examined whether pigs form long-term preferential associations or ‘friendships’ and factors that may influence the formation of these relationships. Thirty-three pigs from 16 litters were housed together from 4 weeks of age. At 10 weeks they were split into two groups of 16 and 17 pigs and each introduced into 3.05 m × 3.66 m observation pens (1st pen). At 17 weeks the two groups swapped pens (2nd pen). The lying patterns of each group were recorded over 3 weeks in both the 1st and 2nd pens. To identify dyads with preferential associations, association indices were calculated for each pair based on their lying patterns and analysed using SOCPROG1.3 and the permutation method [Whitehead, H., 1999. Programs for analysing social structure. SOCPROG 1.2, http://is.dal.cal/~whitelab/index.htm]. Dyads with high association indices for at least 2 out of 3 weeks in either pen, i.e. =0.10 (twice the mean), were classed as having preferential associations. Mantel tests were used to examine the relationship between the relative sex, weight, familiarity and relatedness of a dyad and their level of association and to examine consistency of associations between pens. The existence of preferential associations was identified in both groups, since the standard deviations for the observed half-weight association index means were significantly higher than for the randomly permuted half-weight association index means (P < 0.001). Of the 33 pigs observed, 32 formed preferential associations with one or more pigs in their group, resulting in 50 dyads. Only six dyads (12 pigs) formed preferential associations in both pens, suggesting that the remaining dyads either formed short-term associations only or were simply displaying a shared preference for the same lying location. Levels of association between pens showed no significant correlation. The relative sex, weight, familiarity and relatedness of dyad members also showed no significant correlation with their level of association. These findings suggest that unrelated pigs are capable of forming preferential associations. However, it is unclear whether such associations are widespread or important to pigs, since most dyads’ preferential associations were not consistent between pens.

SK1-like functors for division algebras

We investigate the group valued functor G(D) = D*/F*D' where D is a division algebra with center F and D' the commutator subgroup of D*. We show that G has the most important functorial properties of the reduced Whitehead group SK1. We then establish a fundamental connection between this group, its residue version, and relative value group when D is a Henselian division algebra. The structure of G(D) turns out to carry significant information about the arithmetic of D. Along these lines, we employ G(D) to compute the group SK1(D). As an application, we obtain theorems of reduced K-theory which require heavy machinery, as simple examples of our method.

Reduced K-theory for Azumaya algebras

Abstract In the theory of central simple algebras, often we are dealing with abelian groups which arise from the kernel or co-kernel of functors which respect transfer maps (for example K-functors). Since a central simple algebra splits and the functors above are “trivial” in the split case, one can prove certain calculus on these functors. The common examples are kernel or co-kernel of the maps Ki(F)?Ki(D), where Ki are Quillen K-groups, D is a division algebra and F its center, or the homotopy fiber arising from the long exact sequence of above map, or the reduced Whitehead group SK1. In this note we introduce an abstract functor over the category of Azumaya algebras which covers all the functors mentioned above and prove the usual calculus for it. This, for example, immediately shows that K-theory of an Azumaya algebra over a local ring is “almost” the same as K-theory of the base ring. The main result is to prove that reduced K-theory of an Azumaya algebra over a Henselian ring coincides with reduced K-theory of its residue central simple algebra. The note ends with some calculation trying to determine the homotopy fibers mentioned above.