Clear-Cell Follicular Adenoma of Ectopic Thyroid in the Submandibular Region

We used a discontinuous Percoll density gradient centrifugation to prepare enriched populations of prolactin (PRL), growth hormone (GH), and folliculo-stellate (FS) cells from rat anterior pituitaries in order to characterize these various cell populations. After cell dissociation and centrifugation, enriched PRL cells (55% of total cells as determined by immunocytochemistry [ICC] were present in Fraction 1 (Fr1) (density ([d]) = 1.059). Fr2 (d=1.071) had enriched S100-positive FS cells (31% of total cells), but enriched GH cell (60% of total cells) were present in Fr3 (d=1.094). Interleukin 6 (IL-6) was secreted mainly by enriched PRL cells in Fr1 (350 pg/mL/106 cells) and Fr2 (194 pg/mL/106 cells), and much less by the enriched GH cells inFr3 (16 pg/mL/106). Proliferation studies with combined 3H-thymidine and ICC for pituitary hormones showed that only the PRL cell had significant prolifereative activity. Immunostaining showed that immediately after separation, all three isoforms of nitric oxide synthase (NOS) were expressed anterior pituitary cells. After 3 d of culture, there was a marked increase in nuclear staining for neuronal NOS (nNOS) in all three fractions, whereas inducible NOS (iNOS) and endothelial NOS (eNOS) rexpression did not change significantly. These results indicate that: 1. Enriched populations of PRL, FS, and GH pituitary cells can be readily obtained with a rapid discontinuous percoll density separation procedure. 2. PRL cells from different fractions of the gradient show differenet proliferation rates and IL-6 secretion varied in different enriched cell populations. 3. Although all three isoforms of NOS were expressed in rat pituitary cells, nNOS is the prindipal isoform in anterior pituitary cells, and its expression was icreased after 3 d of culture of anterior pitutuitary cells.     

Further study on the excitation of pyramidal tract cells by intracortical microstimulation

The effective spread of stimulating current for pyramidal tract (PT) cells and fibers was studied using a method of cancelling the shock artifacts and the following results were obtained:

Reassembly of Anterior Pituitary Organization by Hanging Drop Three-Dimensional Cell Culture

The anterior pituitary gland comprises 5 types of hormone-producing cells and non-endocrine cells, such as folliculostellate (FS) cells. The cells form a lobular structure surrounded by extracellular matrix (ECM) but are not randomly distributed in each lobule; hormone-producing cells have affinities for specific cell types (topographic affinity), and FS cells form a homotypic meshwork. To determine whether this cell and ECM organization can be reproduced in vitro, we developed a 3-dimensional (3D) model that utilizes hanging drop cell culture. We found that the topographic affinities of hormone-producing cells were indeed maintained (ie, GH to ACTH cells, GH to TSH cells, PRL to LH/FSH cells). Fine structures in hormone-producing cells retained their normal appearance. In addition, FS cells displayed well-developed cytoplasmic protrusions, which interconnected with adjacent FS cells to form a 3D meshwork. In addition, reassembly of gap junctions and pseudofollicles among FS cells was observed in cell aggregates. Major ECM components—collagens and laminin—were deposited and distributed around the cells. In sum, the dissociated anterior pituitary cells largely maintained their in vivo anterior pituitary architectures. This culture system appears to be a powerful experimental tool for detailed analysis of anterior pituitary cell organization.     

Detection of red cell sensitisation by antibody and complement: Current practice and future perspectives

In autoimmune haemolytic anaemia (AHA) antibody(ies) are directed at ‘self’ red blood cells (RBC) and can effect their destruction. This removal of RBC may be enhanced by the additional presence of complement on the cell membrane. The diagnosis of AHA requires the demonstration of such antibody(ies), which are able to sensitise autologous erythrocytes in vivo. AHA has been described in a variety of animal species but the techniques employed in the laboratory diagnosis have, generally, been extrapolated from those used in human serology. The application of newer and more sensitive techniques to the assessment of RBC sensitisation with antibody and complement, has improved the diagnosis of AHA. Furthermore, it is now possible to assess the significance of the degree of RBC sensitisation and to evaluate treatment regimens. Approaches to the assessment of RBC sensitisation are:

Evidence That Folliculo-Stellate Cells Mediate the Inhibitory Effect of Japanese Kampo Medicine,Unkei-To,on Growth Hormone Secretion in Rat Anterior Pituitary Cell Cultures

PROBLEM: Cytokine-induced neutrophil chemoattractant (CINC) was reported to influence anterior pituitary hormone release. We recently found that Unkei-to, one of the Japanese Kampo medicines, stimulated CINC secretion by rat anterior pituitary cells and the pituitary folliculo-stellate (FS)-like cell line (TtT/GF). Therefore, the effect of Unkei-to on growth hormone (GH) secretion by rat anterior pituitary cells was investigated. METHOD OF STUDY: Dispersed normal anterior pituitary cells, the folliculo-stellate-like cell line TtT/GF, and the GH₃ cell were used to test the effect of Unkei-to on GH secretion. In reconstitutive coculture experiments, TtT/GF cells were mixed with GH₃ cells at a ratio (TtT/GF cells: GH₃ cells) of 1:99. From this mixture, cells were seeded onto plates at a density of 10⁴ cells/well and were cultured for 5 days. The cells were then used in the experiments. RESULTS: Unkei-to at 20 μg/ml significantly inhibited GH secretion by normal anterior ptuitary cells within 12 hr of incubation. In contrast Unkei-to stimulated GH secretion by GH₃ cells in a time- and dose-dependent manner, suggesting that an accessory cell type was involved. To assess the contribution of CINC as a paracrine factor, an experiment using a reconstitutive coculture system was performed, and Unkei-to was found to inhibit GH secretion when GH₃ cells were cocultured with TtT/GF cells. The addition of anti-CINC antibody to the reconstitutive coculture system antagonized Unkei-to-inhibited GH secretion. CONCLUSION: CINC, which was secreted from FS cells by Unkei-to, may be responsible for mediating the inhibitory effect of Unkei-to on GH secretion by rat anterior pituitary cells.     

Pollution-induced airway disease and the putative underlying mechanisms

Conclusions  Taken together, the findings of both epidemiological and laboratory-based studies provide evidence that exposure to air pollutants generated from petrol and diesel-burning engines are likely to precipitate attacks of asthma and rhinitis, and possibly contribute to the increase in prevalence of these disorders. The mechanisms by which pollutants exert their effects may be either indirect (modulation of allergenicity of airborne allergens) or direct:

Anti-endothelial cell antibodies and autoimmune diseases

AECA represent a new family of autoantibodies detectable in systemic autoimmune diseases. Different findings support their poten-tial importance both from a diagnostic and a prognostic point of view:

Diffuse mesangial cell proliferation in focal sclerosing glomerulonephritis

Morphometrical and clinical investigations were performed in 34 patients with the so-called hypercellular form of focal glomerulosclerosis (FGS), i.e., a form showing clear diffuse mesangial hypercellularity beside focal sclerosis with the light microscope. This form was compared with focal glomerulosclerosis without remarkable mesangial hypercellularity, with mild mesangioproliferative glomerulonephritis (gn), as well as with normal kidneys.The results were as follows:

Genetic factors controlling airway responsiveness

The airways have a repertoire of defense mechanisms against stimuli entering the tracheobronchial tree. Bronchial asthma can be regarded as an exaggerated airway response to different exogenous stimuli. There is indirect evidence that asthmatics form a heterogeneous population characterized by an increased responsiveness in one or more of these airway defense mechanisms. Furthermore, human investigations and animal experiments suggest that both environmental and genetic factors operate at these different levels. The aim of the present paper is to review the evidence that genetic factors control the airway response to exogenous stimuli and correlate these observations with the evidence that genetic factors are involved in the pathogenesis of human bronchial asthma. The airways are controlled by a complex network of defense mechanisms that aim at guarding the normal physiological function of the airways, i.e., the conduction and conditioning of air (1,2). The airway defense mechanisms can be divided roughly in the following more or less interwoven aspects

Investigations into human thorotrastosis

The subjects of investigation were 13 dead thorotrast patients, 10 male, 3 female, with ages ranging from 45 to 79 years. Two thousand organ and tissue specimens were investigated by means of autopsy and by both microscopic-autoradiographic and neutron activation analysis in order to detect late effects and to determine on approximate mean concentration of ²³²Th (mg per g of tissue).A comparison between late effects and concentrations of the dye medium led to the following conclusions:

Spinal branching of corticospinal axons in the cat

Branching patterns of single corticospinal (CS) neurons were studied in the cat by activating these neurons antidromically from various regions of the spinal cord.