Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019621 (Langerhans cell histiocytosis)
 3,250 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Circulating immune complexes composed of HBcAg and anti-HBc have been demonstrated recently in patients with hepatitis B virus replication. After dissociation of immune complexes by chaotropic ions, HBcAg was quantified radioimmunologically. In the present study, we describe 10 patients with hepatitis B virus replication, absent or delayed anti-HBc formation and exposed HBcAg in serum. Four of the 10 patients had acute hepatitis, and six patients had chronic persistent hepatitis. In seven of 10 patients, a secondary immune defect was apparent due to acquired immunodeficiency syndrome, leukemia, histiocytosis X, sarcoidosis or end-stage renal disease. Electron microscopy demonstrated that Dane particles from anti-HBc-negative patients were agglutinated after addition of monoclonal anti-HBc antibodies, whereas Dane particles from anti-HBc-positive sera did not show agglutination. Monoclonal HBsAg-specific antibodies aggregated Dane particles independent of the presence of anti-HBc. Circulating HBcAg was always associated with the Dane particle fraction after density gradient separation. Hepatitis B virus core proteins from patients with and without anti-HBc studied by immunoblotting after sodium dodecyl sulfate-gel electrophoresis showed identical patterns. Hepatocytes from anti-HBc-negative patients were positive for HBcAg but negative for immunoglobulin G by immunofluorescence technique. The data indicate that HBcAg may also be expressed on the surface of Dane particles, where it is commonly masked by anti-HBc.
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PMID:HBcAg expressed on the surface of circulating Dane particles in patients with hepatitis B virus infection without evidence of anti-HBc formation. 274 30

Respiratory tract fluid, produced from an enormous area spanning the mucosa of the nose to the alveolar surface, is a complex mixture of serum transudate and locally secreted proteins and glycomucoproteins and of inflammatory and immune effector cells intermingled. Its analysis is important in understanding the pathogenesis of respiratory diseases and remains essential for the clinical diagnosis of most lung disorders. Many basic facts about the formation and composition of this fluid remain unknown, and little information exists about absorptive mechanisms along the airways. Respiratory fluid is not homogeneous but has unique regional characteristics that are becoming better appreciated as more selective sampling methods are devised. Above all, it is a dynamic substance in healthy airways and diseased ones, and any specimen is just a point-in-time sample that can change in composition, often making serial analysis and comparisons necessary. Nasal fluids currently have limited diagnostic application except in allergic rhinitis. Expectorant (sputum) telescopes fluid and cells from all areas and is not from a specific locale, so the trend is to retrieve more selective and regional specimens of airways fluids. Technology largely does not exist to collect area specimens, except for bronchoalveolar lavage, which generally samples the alveolar surface. Clearly, bronchoalveolar lavage fluid analysis has been the favored way to characterize the peripheral air-spaces for the past 10 years or so, and most of this monograph has been devoted to normal data derived from lavage specimens and to a few examples of lung disease that reflect this burgeoning application. In many respects, results obtained from lavage fluid are virtually in catalogue form at present, and it remains to the future to know how some of the observations will help make diagnosis better or elucidate pathogenic mechanisms. Generally, bronchoalveolar lavage fluid analysis has led to better concepts of immunopathology of many diseases and provided new ways to monitor the evolution of certain diseases, especially the diffuse interstitial lung disorders, but development of specific criteria for diagnosis has been less rewarding. However, certain patterns of lymphocyte-predominant alveolitis, suggesting sarcoidosis or hypersensitivity diseases, recognition of specific T lymphocyte defects and opportunistic microorganisms as in AIDS, and the use of microprobe electron analysis to identify cellular particulates all point to more precision of diagnosis. Alveolar proteinosis and histiocytosis X may be detected from lavage fluid components. The prospects are truly exciting.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Respiratory tract fluids: analysis of content and contemporary use in understanding lung diseases. 636 22