Rheumatoid arthritis synovial macrophage-osteoclast differentiation is osteoprotegerin ligand-dependent

Osteoprotegerin ligand (OPGL) is a newly discovered molecule which is essential for osteoclast differentiation. Both OPGL and its soluble decoy receptor, osteoprotegerin (OPG), which inhibits osteoclast formation, are known to be produced by osteoblasts and inflammatory cells found in the rheumatoid arthritis (RA) synovium. In this study, RA synovial macrophages were incubated in the presence or absence of OPGL, macrophage-colony stimulating factor (M-CSF), and dexamethasone for various time points. The results indicated that osteoclast formation from RA synovial macrophages is OPGL-dependent and that OPGL and M-CSF are the only humoral factors required for RA synovial macrophage-osteoclast differentiation. OPG was found to inhibit osteoclast formation by RA synovial macrophages in a dose-dependent manner. This study has shown that macrophages isolated from the synovium of RA patients are capable of differentiating into osteoclastic bone-resorbing cells; this process is OPGL- and M-CSF-dependent and is modulated by corticosteroids. Cellular (T and B cells, dendritic cells) and humoral factors in RA synovium and bone may influence osteoclast formation and bone resorption by controlling OPGL/OPG production.     

Chromosome mapping of cell membrane antigens expressed on activated B cells

Hybrids formed by fusion of either human acute lymphoblastic or chronic lymphocytic leukemia cells and the mouse myeloma P3.X63.Ag8/653 have been used to show that the expression of two cell surface antigens, Bp37 and p76, associated with B cell activation and detected by the monoclonal antibodies BB1 and BB2, respectively, segregate with human chromosomes 12 and 19, respectively. Another antigen expressed on activated B cells (p24) also maps to chromosome 12 (Katz et al., Eur. J. Immunol. 1984. 13: 1008) which is of interest in the light of the frequent involvement of this chromosome in certain B cell leukemias and lymphomas.     

Rapid detection of clindamycin resistance in Bacteroides spp.

High-level resistance to clindamycin can be accurately detected by the Wadsworth disk identification test. Of the 98 isolates of the Bacteroides fragilis group that were tested, 90 were inhibited by the 60-micrograms erythromycin disk and had clindamycin minimal inhibitory concentrations of less than or equal to 3.2 micrograms/ml. Of the remaining eight isolates, all were resistant to the erythromycin disk and had clindamycin minimal inhibitory concentrations of greater than or equal to 100 micrograms/ml.     

Extraskeletal Osteosarcoma with Unusual Ultrastructural Features

A case of extraskeletal osteosarcoma was observed in the thigh of a 33-year-old male patient. Ultrastructurally the tumor was characterized by the presence of a particular dense type of cell, the nucleus of which showed a characteristic combination of features: large amounts of condensed mar-ginated chromatin, prominent perichromatin granules, vermicellar bodies, and undulating microtubules. The tumor also contained intermediate-type cells with a more typical osteoblastic appearance, and more blastic cells. All three cell types contained varying amounts of dilated rough endoplasmic reticulum with prominent inclusions of crystalline material showing a hexagonal or banded pattern, indicating that the cells represent different stages of maturation rather than genuinely different types of cells. Dense cells showing the same characteristic combination of nuclear features have been described once before in a case of parosteal osteosarcoma. Our results indicate that these cells are a particular form of osteogenic cell. The presence of undulating microtubules and vermicellar bodies suggest a possible association with the presence of virus and/or increased levels of interferon.     

Soft tissue infection with Absidia corymbifera in a patient with idiopathic aplastic anemia

We describe a case of primary cutaneous mucormycosis (zygomycosis) in a patient with idiopathic aplastic anemia which responded to surgical debridement and therapy with liposomal amphotericin B. The tissue removed at surgery showed dense infiltration with fungal hyphae on histopathological examination. Primary cultures of tissue on solid media were negative, but Absidia corymbifera was isolated from unprocessed tissue placed in brain heart infusion broth.     

The use of linked DNA polymorphisms for genotype prediction in families with Duchenne muscular dystrophy.

Two DNA restriction fragment length polymorphisms show genetic linkage to the Duchenne muscular dystrophy locus on the short arm of the X chromosome. Examples are given of families in which these polymorphisms can be used in the prediction of genotype for this disorder.     

Well-being and life satisfaction in generalized anxiety disorder: comparison to major depressive disorder in a community sample

BACKGROUND: In most settings, generalized anxiety disorder (GAD) is highly comorbid with major depressive disorder (MDD). This raises uncertainty about the clinical relevance of GAD as a distinct diagnostic entity. The demonstration of functional impairment attached to GAD, independent of that attributable to MDD, would support the importance of GAD as a separate diagnostic category. METHODS: The Ontario Health Survey Mental Health Supplement, a survey of more than 8000 residents aged 15-64 of the Canadian province of Ontario, used the University of Michigan Composite International Interview Schedule (also used in the US National Comorbidity Survey) to assign DSM-III-R diagnoses. Several indicators of disability and quality of life were included. Our analytic strategy was to compare these indices in persons with and without GAD, stratified by MDD comorbidity, and adjusting for the effects of relevant sociodemographic factors (e.g., social class, age, gender) and dysthymia. Odds ratios (ORs) are reported; SUDAAN was used to adjust for the sampling framework. RESULTS: GAD was highly comorbid with MDD on both a lifetime and past-year basis. Both past-year and lifetime MDD and GAD were associated with an increased likelihood of low overall perceived well-being. Both lifetime MDD and GAD were associated with dissatisfaction in one's main activity and with family relationships. LIMITATIONS: Other comorbid Axis I or II conditions might be confounders with impairment; a lower rate of GAD than in some prior surveys bears consideration. CONCLUSIONS: These observations confirm that GAD is associated with an increased likelihood of poor global well-being and life satisfaction, beyond that associated with MDD. Given the chronicity of GAD relative to the more often episodic course of MDD, the long-term functional benefits of treating GAD may be substantial.