The role of recombination signal sequences in the preferential joining by deletion in DH-JH recombination and in the ordered rearrangement of the IgH locus

The bias favoring deletion over inversion in DH-JH rearrangement has been known for years, but the underlying mechanism has yet to be fully defined. It has been suggested that the ratio of deletion/inversion is determined by the combined effect of two factors: (i) the relative strengths of 5' and 3' recombination signal sequences (RSS) of a DH segment, and (ii) the efficiency with which the deletional product (one joint) forms relative to the inversional product (two joints). In this study, we analyzed for the first time the effect of factor 1 alone on the biased 3' RSS utilization in DH-JH joining by using deletional plasmids in an extrachromosomal substrate V(D)J recombination assay. It was found that the 3' RSS and associated coding end (12 bp) mediate recombination more efficiently than the 5' RSS/coding end DH-JH plasmids. These results demonstrate that the effect of the RSS/coding end alone can account, at least partially, for the predominant deletion in DH-JH recombination. The potential effect of the relative strength of RSS and associated coding end on the ordered rearrangement of DH-JH followed by VH to DH-JH was also assessed. When recombination frequencies of D-->J (3' DH to J3) were compared with frequencies of V-- >D (VHPJ14 to 3' DH or VHOX2 to 3' DH), it was found that V-->D joining was, if anything, more efficient than D-->J joining. Therefore, if all three segments were accessible, RSS/coding end effects would not contribute to the ordered rearrangement of the IgH locus.      

Reduction of atherosclerosis in cholesterol-fed rabbits and decrease of expressions of intracellular adhesion molecule-1 and vascular endothelial growth factor in foam cells by a water-soluble fraction of Polygonum multiflorum

Polygonum multiflorum stilbeneglycoside （PMS） is a water-soluble fraction of Polygonum multiflorum Thunb. , one of the most famous tonic traditional Chinese medicines, that has protective effects on the cardiovascular system. The purpose of the present study is to elucidate the effects of PMS on macrophage-derived foam cell functions and the reduction of severity of atherosclerosis in hypercholesterolemic New Zealand White （NZW） rabbits. NZW rabbits were fed for 12 weeks with a normal diet, a high cholesterol diet, or a high cholesterol diet associated with irrigation with different doses of PMS （25, 50, or 100 mg/kg）. Treatment of NZW rabbits fed with high cholesterol diet with 100 mg/kg PMS attenuated the increase in plasma cholesterol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, and plasma triglyceride. Treatment with 50 and 100 mg/kg PMS caused 43% and 60% decrease in atherosclerotic lesioned area ratio to total surface area, respectively. In U937 foam cells, PMS could decrease the high expression of intercellular adhesion molecule （ICAM）-1 protein and the vascular endothelial growth factor （VEGF） protein levels in the medium induced by oxidized lipoprotein when analyzed by flow cytometry. The results proved that PMS is a powerful agent against atherosclerosis and that PMS action could possibly be through the inhibition of the expression of ICAM-1 and VEGF in foam cells.     

Interstitial lung disease in polymyositis and dermatomyositis

OBJECTIVES: To assess prevalence, characteristics, and long-term outcome of interstitial lung disease (ILD) in polymyositis (PM) and dermatomyositis (DM). To determine predictive variables of ILD course in PM/DM, and to define both clinical and biochemical features associated with ILD onset in PM/DM. METHODS: The medical records of 156 consecutive PM/DM patients in 3 medical centers were reviewed. RESULTS: Thirty-six PM/DM patients (23.1%) developed ILD. We observed that 19.4% of patients with ILD had resolution of pulmonary disorders, whereas 25% experienced ILD deterioration. Morbidity and mortality rates were as high as 13.9% and 36.4%, respectively, in PM/DM patients with ILD. Parameters of PM/DM that related to ILD poor outcome were identified as follows: Hamman-Rich-like pattern, initial diffusing capacity of carbon monoxide <45%, neutrophil alveolitis, and histologic usual interstitial pneumonia. Additionally, for the group with ILD, polyarthritis, higher values of erythrocyte sedimentation rate and C-reactive protein, presence of anti-Jo-1 antibody, and characteristic microangiopathy were significantly more frequent. CONCLUSION: Our series underlines the high frequency of ILD in PM/DM patients, resulting in increased morbidity and mortality rates. It also indicates that PM/DM patients should routinely be screened for ILD, even those patients without anti-Jo-1 antibody, because 69% of our ILD patients were seronegative for the anti-Jo-1 antibody. Our findings further suggest that PM/DM patients presenting with factors predictive of ILD poor outcome may require more aggressive therapy.     

Systemic allergic vasculopathy after naproxen (author's transl)]

The authors report a case of hypersensitivity angiitis presenting with cutaneous, muscular, articular, and renal signs. They suggest a possible etiological mechanism for such disorders: a circulating immune-complex disease, and criticize the often improper interpretation of the results of lymphoblast transformation tests. Hypersensitivity angiitis, "ground base disease", requires investigation for possible underlying immunity abnormalities or neoplasms.     

Dermatopolymyositis and pulmonary fibrosis associated with Gougerot-Sjogren syndrome. Study of 3 cases

3 new cases of dermatomyositis associated with diffuse interstitial pulmonary fibrosis and, more exceptionally, with Sj?gren's syndrome are reported. The pulmonary fibrosis observed in patients with dermatomyositis differs from that found in other connective tissue diseases in that it follows a more acute course and may respond to corticosteroids. Thus, in 2 of these patients treated with corticosteroids (combined in 1 case with cyclophosphamide) the high percentage of lymphocytes and polymorphonuclears in the broncho-alveolar lavage fluid, which reflects alveolitis activity, was reduced and the pulmonary fibrosis was cured in one patient and stabilized in the other.     

Influence of age on the clinical and biological characteristics of systemic scleroderma

PURPOSE: The present study was aimed at assessing the influence of age on clinical and biological features of systemic sclerosis. METHODS: This retrospective study included 151 consecutive patients with systemic sclerosis. The median age at diagnosis was 50.0 years (range: 10-84 years). Patients were divided into two groups according to their age (lower than 50.0 years of age: 73 patients, equal to or above 50 years of age: 78 patients). The following features were compared between the two groups: gender, disease duration, extent of skin sclerosis, Crest syndrome, lung fibrosis, secondary Sj?gren's syndrome, antinuclear, anticentromere, and anti-Scl70 antibodies. RESULTS: The disease duration was significantly higher in patients over 50 years of age (7.1 +/- 6.8 years vs 5.5 +/- 5.0 years, P < 0.05). Crest syndrome, secondary Sj?gren's syndrome and anticentromere antibodies were significantly more common in patients over 50 years of age (17/73 vs 30/78, P < 10(-2); 9/73 vs 20/78, P < 10(-2), and 19/73 vs 31/78, P < 0.05; respectively). Anti-Scl70 antibodies were significantly more common in patients under 50 years of age (17/73 vs 10/78, P < 10(-2)). No significant difference was found in regard to the other features. CONCLUSION: The clinical and biological patterns of systemic sclerosis are different according to the age at disease onset. Crest syndrome including anticentromere antibodies and Sj?gren's syndrome is more common in elderly patients, while anti- Scl-70 antibodies are more common in younger patients. This suggests the involvement of various mechanisms in the pathogenesis of systemic sclerosis, and that these mechanisms may depend on the age.