Algae in cytologic smears.

OBJECTIVE: To desmonstrate the presence of algae in smears and establish their significance. STUDY DESIGN: Microscopic examination of smears stained by the Papanicolaou technique. RESULTS: We found 12 different species of algae, clustered in three categories: Cyanophita (blue algae), Chrysophyta (yellow algae) and Chlorophyta (green algae). CONCLUSION: Algae in smears are infrequently observed, with few bibliographic references. Their presence is due to intrinsic or extrinsic contamination. They may be confused with other structures, such as fungi, Charcott crystals or adenocarcinoma cells.     

Microfilariae of Wuchereria bancrofti in cytologic smears

Microfilariae of Wuchereria bancrofti were observed in cytologic material in 35 cases. The material included cervicovaginal smears (17 cases), effusions (14), urine (2), bronchial washings (1) and ovarian cyst fluid (1). The initial diagnosis was made from the cytologic smear in all cases; none had clinical filariasis. Symptomatic vaginal bleeding in 9 of the 17 cases with microfilaria-positive cervicovaginal smears was reflected in the large numbers of red blood cells found in the smear. Blood eosinophilia was present in 11 of 19 cases investigated. Eosinophils were seen in the smears in 20 cases. In the majority of the cases of effusions with microfilariae the effusions were malignant. Significant adherence of inflammatory cells and macrophages to microfilariae was present in 7 of the 35 cases. The significance of these findings is discussed.     

Preparation of methacrylate-embedded cytologic smears from prefixed cells

A new method of preparing smears of alcohol-fixed cytologic material by using methacrylate embedding medium to make the cells adhere on plain glass slides is presented. After centrifugation, the cytologic material was mixed with Lowicryl K4M embedding medium and smeared on slides. The polymerization process was achieved by exposing the slides to ultraviolet light. The morphology in such smears was similar to that of specimens prepared by the filter technique. The methacrylate method does not have the most common disadvantages of the filter technique--the development of air bubbles over time and the visually disturbing presence of the filter.     

Cryosurgery of parathyroid glands

The effectiveness of cryosurgery in destruction of parathyroid glands in rats was studied by comparison of 4 experimental groups: 1. cryosurgery utilizing 3 patterns of repetitive freezing, 2. excision, 3. sham operation, or 4. no treatment. Evaluation included clinical observation of respirations and voice, serum calcium concentration, and histologic examination of parathyroid tissue. The results indicate that the extent of destruction of parathyroid glands in rats can be controlled by specific cryosurgical techniques without thyroidectomy or risk of permanent injury to the recurrent laryngeal nerves.     

Immunocytochemical localization of parathyroid hormone in rabbit parathyroid glands

Immunocytochemical localization of parathyroid hormone was examined in the rabbit parathyroid gland by means of protein A-gold technique. Protein A-gold particles were observed on the secretory granules and the large secretory granules thought to be storage granules. No protein A-gold particles were observed on cisternae of the endoplasmic reticulum and the Golgi apparatus.     

Parvalbumin is expressed in normal and pathological human parathyroid glands.

The parathyroid glands are of major importance in calcium homeostasis. Small changes in the plasma calcium (Ca2+) concentration induce rapid changes in parathyroid hormone (PTH) secretion to maintain the extracellular Ca2+ levels within the physiological range. Extracellular Ca2+ concentration is continuously measured by a G-protein-coupled Ca2+-sensing receptor, which influences the expression and secretion of PTH. The mechanism of signal transduction from receptor sensing to PTH secretion is not well understood, but changes in PTH secretion are tightly linked to changes in the cytosolic Ca2+ concentration. Using immunohistochemistry and Western blot analysis, we detected the EF Ca2+ binding protein parvalbumin (PV) in normal and in hyperplastic and adenomatous human parathyroid glands. The strongest PV signal was present in chief cells and water clear cells, whereas in oxyphilic cells only a weak signal was observed. Immunohistochemistry and in situ hybridization of the PTH indicated a co-localization of PV and PTH in the same cell types. Because changes in the cytosolic Ca2+ concentration are believed to influence the process of PTH secretion, a possible role of PV as a modulator of this Ca2+ signaling is envisaged.     

A vasopressor factor partially purified from human parathyroid glands.

Recently, a parathyroid hypertensive factor was postulated to play a role in the pathogenesis of hypertension in genetically hypertensive rats. Therefore it was examined, whether in human parathyroid glands a vasopressor substance can be detected. For this purpose, homogenates of hyperplastic parathyroid glands from 20 patients with tertiary hyperparathyroidism were deproteinized and fractionated by gel chromatography. The fractions obtained were tested for vasopressor activity in isolated perfused rat kidneys. A vasopressor fraction containing substances of 0.6-2.5 kDa was identified in the parathyroid glands. The responsible product was heat sensitive, peptidase-, trypsin- and carboxypeptidase y- sensitive and hydrophilic, as it did not bind to hydrophobic reversed-phase gel. These results suggest that parathyroid glands contain a hydrophilic peptide-like vasopressor substance different from the parathyroid hormone.     

Detecting mycobacteria in Romanowsky-stained cytologic smears. A case report

BACKGROUND: Cytologic features of mycobacterial infections are granulomatous inflammation with or without caseous necrosis and the demonstration of acid-fast bacilli with special stains. However, immuno-compromised patients might not mount the expected response. CASE: A routinely used Romanowsky (Leishman) stain was used for the presumptive diagnosis of mycobacterial infection in a 30-year-old man with AIDS. The mycobacteria were identified as inclusions, described as "negative images," in the cytoplasm of macrophages in smears of bone marrow aspirate. They were then confirmed to be acid-fast bacilli with Ziehl-Neelsen stain. CONCLUSION: Negative images of mycobacteria may be seen in Romanowsky-stained cytologic smears from patients with immunodeficiency. This is a rapid and cost-effective way of detecting the mycobacteria before more specific results are available. Such a search should be undertaken routinely in all patients suspected to have such infections.     

X-ray microanalysis of elemental changes in human parathyroid glands in primary and secondary hyperparathyroidism

The elemental composition of chief cells of parathyroid glands from patients with adenomatous primary hyperparathyroidism (HPT) and uremic secondary HPT was studied by X-ray microanalysis. Glands histologically deemed normal were used as controls. The analyses were also carried out on tissue specimens incubated in hypo-, normo- and hypercalcemic media (0.5, 1.25, and 3.0 mM calcium concentration). Analysis of chief cells from normal glands did not reveal any significant differences in ionic composition after exposure to the different calcium concentrations. In chief cells from adenomatous and uremic hyperplastic glands, elemental changes were noted. In comparison with specimens incubated in 1.25 mM calcium medium, cells in 0.5 mM calcium medium had a lower content of potassium and phosphorus. After stimulation with increasing extracellular concentration, an increase in the K/Na ratio was observed, due to a marked decrease of sodium and an increase of potassium: the calcium concentration was almost unchanged. Our findings indicate that in HPT an increase in serum calcium concentration might exert a stimulatory effect on the Na/K pump (sodium pump) and on the calcium-activated potassium channels. Either of these mechanisms might contribute to a lowering of cytoplasmic calcium. Our observations suggest that changes in ionic content of the parathyroid cells may be of importance for the stimulus secretion process in the cells.     

Regeneration of the parathyroid glands in experimental hyperthyroidism

By means of morphological, morphometric and radioautographic methods, regeneration of mechanically traumatized parathyroid glands has been studied in 22 euthyroid and 22 hyperthyroid rats on the 1st-20th days after the operation. The thyroid gland is stimulated by daily injection of thyrotropin (1 ME/100 g of body mass). Twelve non-operated animals (6 hyperthyroid and 6 euthyroid rats) serve as control. In the regenerating parathyroid glands of the hyperthyroid animals in comparison with the euthyroid ones, certain increase of proliferative activity is noted in parathyrocytes and in cells of the granular tissue on the 2d-6th days, a more pronounced hypertrophy of epitheliocytes on the 2d-20th days, hyperplasia of their nucleolar apparatus on the 2d-5th days. The experimental hyperthyroidism stimulates manifestation of restorative processes in the regenerating parathyroid glands during development of active inflammatory reaction in them; however, it does not influence the parameters of the organ's structure studied in the nonoperated animals.