thymic-factor--circulating and Hyperplasia

Benign thymic hyperplasia (TH) is a known feature of hyperthyroidism. In most cases, thymic enlargement is minimal; however, this syndrome may occasionally appear as an appreciable anterior mediastinal mass. Recognition of the benign nature of TH and its regression following treatment of the hyperthyroidism is important to prevent unnecessary surgical procedures. We present a case of TH associated with hyperthyroidism due to Graves' disease.

Topics: Animals; Antithyroid Agents; Diagnosis, Differential; Female; Graves Disease; Humans; Hyperplasia; Immunoglobulins, Thyroid-Stimulating; Indium Radioisotopes; Magnetic Resonance Imaging; Mediastinal Neoplasms; Methimazole; Radionuclide Imaging; Receptors, Thyrotropin; Somatostatin; Thymic Factor, Circulating; Thymoma; Thymus Gland; Thymus Neoplasms; Young Adult

Chorioamnionitis is associated with increased risks of perinatal respiratory failure; however, components of the inflammatory acute-phase response are known to actively promote lung maturation. To manipulate this relationship, we examined the effect of the thymic immunomodulator thymulin on fetal lung mesenchyme-epithelial differentiation during exposure to Escherichia coli lipopolysaccharide (LPS). Gestation day 14 fetal rat lung explants were cultured for 96 h at fetal (23 mmHg) or ambient (142 mmHg) Po(2). Airway surface complexity (ASC, perimeter/ radical area(2)) was greater at fetal vs. ambient Po(2); however, exposure to 0.1-50 microg/ml LPS significantly raised ASC at 2 microg/ml in ambient Po(2) explants. LPS (50 microg/ml) depressed ASC in both conditions to untreated ambient Po(2) control values without changes in necrosis or apoptosis. To manipulate LPS-evoked TNF-alpha and IL-6 release, we exposed explants and A549 cells to combinations of 50 microg/ml LPS, 10 microM ZnCl(2), and 0.1-1,000 ng/ml thymulin at either Po(2). Thymulin+Zn(2+) suppressed and potentiated LPS-evoked TNF-alpha and IL-6 release, yielding an IC(50(TNF-alpha)) of 0.5 +/- 0.01 ng/ml and EC(50(IL-6)) of 1.4 +/- 0.3 ng/ml in A549 cells. This was accompanied by activation of the p38 MAPKMAPKAP-K2 pathway with sustained expression of TNF-alpha and IL-6 transcripts at ambient Po(2). LPS+thymulin+Zn(2+)-treated explants showed proliferation of CCAAT-enhancer binding protein-beta (C/EBPbeta) and fibroblast growth factor-9 immunoreactive mesenchyme, which was abolished by IL-6 antisense oligonucleotides. The posttranscriptional suppression of immunogenic TNF-alpha synthesis coupled with raised IL-6 and C/EBPbeta-dependent mesenchyme proliferation suggests a role for bioactive thymulin in regulating regenerative repair in the fetal lung.

Topics: Adenocarcinoma; Adjuvants, Immunologic; CCAAT-Enhancer-Binding Protein-beta; Cell Differentiation; Cell Division; Cell Line, Tumor; Fetus; Fibroblast Growth Factor 10; Fibroblast Growth Factor 9; Fibroblast Growth Factors; Humans; Hyperplasia; Interleukin-6; Intracellular Signaling Peptides and Proteins; Lipopolysaccharides; Lung; Mesoderm; Oxygen; Protein Serine-Threonine Kinases; Signal Transduction; Thymic Factor, Circulating; Transcription, Genetic; Tumor Necrosis Factor-alpha; Zinc

The state of thyroid, adrenal cortex and testicular endocrine cells during the course of thymalin administration was studied. Morphological signs of transitory inhibition of steroidogenic gland function and thyroid stimulation were revealed in rats with intact immune system. Hyperplastic changes in thyroid epithelium were associated with decreased levels of total T3 and T4 and increased serum level of TTH. Regressive changes in the thyroid parenchyma and hyperplasia of steroid-producing elements of the testis and adrenal cortex in the thymectomized guinea pigs could not be corrected by the thymalin administration 45 days after the operation. Our data suggest the search of possible means of control and correction of the patient endocrine status during the administration of immunomodulators.

Topics: Adjuvants, Immunologic; Adrenal Cortex; Animals; Epithelium; Guinea Pigs; Hyperplasia; Immune Tolerance; Male; Rats; Rats, Inbred Strains; Testis; Thymus Gland; Thymus Hormones; Thyroid Gland; Thyrotropin; Thyroxine; Triiodothyronine

Topics: Adolescent; Adult; Aged; Aging; Animals; Cells, Cultured; Child; Child, Preschool; Epithelium; Female; Humans; Hyperplasia; Infant; Mice; Microbial Collagenase; Middle Aged; Thymic Factor, Circulating; Thymus Gland; Thymus Hormones