Clinical and immunological characteristics of 150 systemic lupus erythematosus patients in Jamaica: a comparative analysis.

Background Epidemiological studies in systemic lupus erythematosus have been reported in the literature in many countries and ethnic groups. Although systemic lupus erythematosus in Jamaica has been described in the past, there has not been a detailed evaluation of systemic lupus erythematosus patients in urban Jamaica, a largely Afro-Caribbean population. The goal of this study was to describe the clinical features, particularly disease activity, damage index and immunological features, of 150 systemic lupus erythematosus subjects. Methods 150 adult patients (≥18 years) followed in rheumatology clinic at a tertiary rheumatology hospital centre (one of two of the major public referral centres in Jamaica) and the private rheumatology offices in urban Jamaica who fulfilled Systemic Lupus International Collaborating Clinics (SLICC) criteria were included. Data were collected by detailed clinical interview and examination and laboratory investigations. Hence demographics, SLICC criteria, immunological profile, systemic lupus erythematosus disease activity index 2000 (SLEDAI-2K) and SLICC/American College of Rheumatology (ACR) damage index (SDI) were documented. Results Of the 150 patients, 145 (96.7%) were female and five (3.3%) were male. The mean age at systemic lupus erythematosus onset was 33.2 ± 10.9. Mean disease duration was 11.3 ± 8.6 years. The most prevalent clinical SLICC criteria were musculoskeletal, with 141 (94%) of subjects experiencing arthralgia/arthritis, followed by mucocutaneous manifestations of alopecia 103 (68.7%) and malar rash 46 (30.7%), discoid rash 45 (30%) and photosensitivity 40 (26.7%). Lupus nephritis (biopsy proven) occurred in 42 (28%) subjects and 25 (16.7%) met SLICC diagnostic criteria with only positive antinuclear antibodies/dsDNA antibodies and lupus nephritis on renal biopsy. The most common laboratory SLICC criteria were positive antinuclear antibodies 136 (90.7%) followed by anti-dsDNA antibodies 95 (63.3%) and low complement (C3) levels 38 (25.3%). Twenty-seven (18%) met SLICC diagnostic criteria with only positive antinuclear antibodies/anti-dsDNA antibodies and lupus nephritis on renal biopsy. Mean SLEDAI score was 6.9 ± 5.1 with a range of 0-32. Organ damage occurred in 129 (86%) patients; mean SDI was 2.4 ± 1.8, with a range of 0-9. Conclusion These results are similar to the clinical manifestations reported in other Afro-Caribbean populations; however, distinct differences exist with respect to organ involvement and damage, particularly with respect to renal involvement, which appears to be reduced in our participants.

Mechanisms involved in 3',5'-cyclic adenosine monophosphate-mediated inhibition of the ubiquitin-proteasome system in skeletal muscle.

Although it is well known that catecholamines inhibit skeletal muscle protein degradation, the molecular underlying mechanism remains unclear. This study was undertaken to investigate the role of beta(2)-adrenoceptors (AR) and cAMP in regulating the ubiquitin-proteasome system (UPS) in skeletal muscle. We report that increased levels of cAMP in isolated muscles, promoted by the cAMP phosphodiesterase inhibitor isobutylmethylxanthine was accompanied by decreased activity of the UPS, levels of ubiquitin-protein conjugates, and expression of atrogin-1, a key ubiquitin-protein ligase involved in muscle atrophy. In cultured myotubes, atrogin-1 induction after dexamethasone treatment was completely prevented by isobutylmethylxanthine. Furthermore, administration of clenbuterol, a selective beta(2)-agonist, to mice increased muscle cAMP levels and suppressed the fasting-induced expression of atrogin-1 and MuRF-1, atrogin-1 mRNA being much more responsive to clenbuterol. Moreover, clenbuterol increased the phosphorylation of muscle Akt and Foxo3a in fasted rats. Similar responses were observed in muscles exposed to dibutyryl-cAMP. The stimulatory effect of clenbuterol on cAMP and Akt was abolished in muscles from beta(2)-AR knockout mice. The suppressive effect of beta(2)-agonist on atrogin-1 was not mediated by PGC-1alpha (peroxisome proliferator-activated receptor-gamma coactivator 1alpha known to be induced by beta(2)-agonists and previously shown to inhibit atrogin-1 expression), because food-deprived PGC-1alpha knockout mice were still sensitive to clenbuterol. These findings suggest that the cAMP increase induced by stimulation of beta(2)-AR in skeletal muscles from fasted mice is possibly the mechanism by which catecholamines suppress atrogin-1 and the UPS, this effect being mediated via phosphorylation of Akt and thus inactivation of Foxo3.

Thrice out of Africa: ancient and recent expansions of the honey bee, Apis mellifera.

We characterized Apis mellifera in both native and introduced ranges using 1136 single-nucleotide polymorphisms genotyped in 341 individuals. Our results indicate that A. mellifera originated in Africa and expanded into Eurasia at least twice, resulting in populations in eastern and western Europe that are geographically close but genetically distant. A third expansion in the New World has involved the near-replacement of previously introduced "European" honey bees by descendants of more recently introduced A. m. scutellata ("African" or "killer" bees). Our analyses of spatial transects and temporal series in the New World revealed differential replacement of alleles derived from eastern versus western Europe, with admixture evident in all individuals.