Morphological observations on the normal human cardiac glands

The majority of human cardiac glands that lie immediately distal to the termination of esophageal epithelium are compound or branched tubular glands. They empty into overlying gastric pits. The glands of this region are often organized into lobule-like complexes by the surrounding connective tissue of the lamina propria. The secretory tubules contain mucous cells, parie-tal cells and endocrine cells. The mucous cell is the most common cell type observed and appears to comprise two populations. The majority are pyramidal in shape and show numerous spherical, electron-dense secretory granules. Profiles of rough endoplasmic reticulum are observed scattered throughout the cytoplasm and Golgi complexes occupy a supranuclear position in relation to forming secretory granules. Morphologically this cell type appears similar to the mucous neck cell of the fundus. Secretory granules of a second mucous cell type are mottled in appearance and show an area of increased electron density near the limiting membrane. Parietal cells are observed and appear identical to those in the fundus. The large number of endocrine cells present raises questions concerning the traditional concept of the function of these particular glands.     

Morphological and histochemical study of human submucosal laryngeal glands

Background: The respiratory submucosal glands are a major source of secretions in the airway. Human submucosal laryngeal glands have been scarcely studied, with no works existing about their ultrastructure and histochemistry. Methods: Samples of epiglottis, ventricle, false vocal folds and true vocal folds were fixed in 10% buffered formalin for histochemical study with conventional and carbohydrate lectin histochemistry. Other samples were fixed in 2.5% glutaraldehyde and conventionally processed for transmission electron microscopy. Results: The human submucosal laryngeal glands are composed of serous tubules; mucous tubules; collector duct; and final portion of this duct. The serous cells showed sialosulphomucins and affinity for WGA and Con-A lectins. With a previous treatment with neuraminidase, they also labelled with PNA. The mucous cells contained sialosulphomucins and showed affinity for WGA and DBA lectins in the samples proceeding from blood group A, and for WGA, UEA-I and LTA with those from blood group O. Ultrastructurally, the serous cells presented a wide variety of granules, cells in which seromucous granules predominated. The mucous cells presented larger-sized granules which were very electron-lucent. The collector duct was composed of mitochondria-rich cells and basal cells. A cell which we have termed “intermediate” was identified in the transition zone between the mucous tubules and the collector duct, and in the final portion of the collector duct. It had morphological characteristics as if it were a transition between a goblet cell and collector duct cell. Some nerve endings with cholinergic and peptidergic vesicles were found among the myoepithelial cells. Conclusions: These glands presented some histological differences from the bronchial glands, the mucous secretion was related to the blood group antigens, and the serous cells showed a wide variability in their secretory granules, many of them being of a seromucous type. © 1994 Wiley-Liss, Inc.     

Morphological and histochemical observations on the intestinal epithelium of Ascaridia galli (Nematoda: Ascaridida)

Summary The intestinal epithelium of Ascaridia galli has been studied with various cytological and cytochemical techniques. It consists of large epithelial cells resting on a thick collagenous basal lamina. Their luminal surface is provided with microvilli. The intestinal cells store considerable amounts of glycogen and neutral lipids. Some intracellular granular inclusions, which stain for proteins, phospholipids and lipoproteins, are distributed throughout the cytoplasm. The brush border is composed of microvilli whereas the outer surface coat consists of saliva resistant PAS-positive material. The detailed histochemical analysis of surface material has revealed that it is composed of nonacetylated acid mucopolysaccharides rich in hyaluronic acid with carboxylate polyanions. The brush border shows intense activities of acid phosphatase and glucose-6-phosphatase, moderate of ATPase, and lipase, weak of 5-nucleotidase. Acid phosphatase-positive intracellular structures are seen in the intestinal epithelium which form distinct aggregations.     

Morphological observations on the Harderian gland of the North American opossum (Didelphis virginiana)

Summary The Harderian gland of the North American opossum (Didelphis virginiana) is large and well developed, despite the absence of a nictitating membrane in the adult of this species. The elongate glands are surrounded by a delicate connective tissue capsule from which thin septae extend, subdividing the gland into numerous lobules. The secretory units of the opossum Harderian gland are drained by a well defined but not extensive intralobular and interlobular duct system. Most of the secretory end pieces consist of tubuloalveolar units with widely dilated lumina filled with secretory product. Numerous intact lipid vesicles suspended within an amorphous material constitute the luminal contents. Cells lining the tubuloalveolar secretory endpieces are usually columnar in shape, and characterized by numerous lipid-containing secretory vesicles and aggregations of polytubular complexes 40–60 nm in diameter. In addition, these cells contain numerous large irregularly shaped mitochondria, whose matrix is of considerable electron density. Intralobular and interlobular ducts are lined by electron-lucent epithelial cells that lack both the lipid-containing vesicles and the large mitochondria, although typical smaller mitochondria are found scattered within the cytoplasm. Both secretory endpieces and ductal elements are invested by an abundance of myoepithelial cells. A second, smaller serous type of secretory unit may occur near the centre of some Harderian gland lobules. In these units secretory tubules and acini are compactly arranged surrounding a narrow lumen. Serous cells are pyramidal in shape and the cytoplasm is characterized by numerous electron-dense secretory granules and scattered profiles of rough endoplasmic reticulum. Basolateral cell membranes show extensive infoldings and intercellular canaliculi are present. The overall size of cells forming the serous secretory units is much less than that comprising the tubuloalveolar secretory endpieces.     

Comparative histochemical observations on the excretory system of helminth parasites

Summary The excretory canals of Ascaridia galli (Nematoda) and the protonephridial ducts of Cotylophoron cotylophorum (Trematoda) and Raillietina cesticillus (Cestoda) have been studied with regard to the histochemical localization of lipids, carbohydrates and hydrolytic enzymes. Distinct excretory organs are absent in the acanthocephalan Centrorhynchus corvi. Triglycerides, phospholipids and lipoproteins are seen in association with the wall of excretory canals of A. galli and R. cesticillus, and phospholipids and lipoproteins at the corresponding site in C. cotylophorum. The physiological significance of lipids in association with excretion of substances has been discussed. Low molecular weight glycogen is present in the lumen of excretory canal of A. galli but not in other worms.The common feature of the excretory canals is the presence of enzyme activities of nonspecific alkaline phosphatase and Mg²⁺-dependent ATPase. Activity of acid phosphatase is seen only in the excretory canals of A. galli. Glucose-6-phosphatase is present in A. galli and C. cotylophorum and absent in R. cesticillus. Weak reaction of 5-nucleotidase is present in the excretory canals of helminth species studied here. The role of these enzymes in transportation of substances across the wall of excretory canals and also in ionic regulation has been discussed in detail.     

Extracellular accumulations in the avian pituitary gland: histochemical analysis in two species of Indian wild birds

Extracellular accumulations of two distinct types, colloid-filled follicles and fibrous-material-containing cysts, were observed in the pituitary gland of two species of Indian wild birds, Halcyon smyrnensis perpulchra and Lonchura striata striata. Colloid follicles were regular structures and distributed throughout the pars distalis (PD). The fibrous cysts were irregular structures, bigger than the colloid follicles and mostly observed towards the ventral margin of the PD. Sometimes disruption of the outer margin with depletion of fibrous material from the cavity was observed. Hormone-secreting cells of various types, anti-adrenocorticotropic-hormone-, anti-prolactin-, anti-growth-hormone- and anti-luteinizing-hormone-immunoreactive cells were encountered bordering both the colloid follicles and fibrous cysts. Neither the colloid nor the fibrous material showed any immunoreaction to any of the pituitary hormone antisera. On histochemical staining colloid was positive to periodic acid-Schiff (PAS) and fibrous materials stained with Alcian blue-PAS-orange G staining. Colloid depositions in the pituitary gland of these two wild birds were correlated to age, more in numbers in the adult birds than in the young ones. Fibrous-material-containing cysts were elucidated in the pituitary gland of adult birds only. These were more prevalent in the pituitary of reproductively active birds. Regular morphology of the colloid follicles, overall distribution in the adenohypophysis and dense nature of deposition of the colloid suggest the accumulation of this type may be the secretory products of both granulated and agranulated pituitary cell types. Absence of immunoreactivity of the colloid against pituitary hormone antisera points out that the storage form may differ chemically from the bioactive hormones. The spatial distribution of fibrous-material-containing cysts mostly towards the ventral PD, observations of immunoreactive cell fragmentations inside the cysts, and their disrupted margins suggest these structures may have some role in discharging the intraglandular degradation products.     

双峰驼泪腺的解剖学与组织化学特点

目的:探究双峰驼泪腺(主泪腺、第三眼睑上腺和哈氏腺)的解剖学、组织学及组织化学特点,为研究双峰驼泪腺的生理机能提供形态学依据.方法:健康无眼疾双峰驼 5 峰,对泪腺、第三眼睑上腺、哈氏腺进行大体解剖学、组织学和组织化学研究.结果:双峰驼主泪腺位于眼球背外侧,呈灰白色不规则三角形,腺单位为管泡状,呈 PAS 阳性、阿利新蓝阳性.第三眼睑上腺位于眼球前内侧面,包裹第三眼睑软骨,呈卵圆形,管泡状腺泡,主要呈 PAS 阳性.哈氏腺位于第眼三睑上腺底部,腺单位有管泡状腺泡和大管腔腺泡,主要呈 PAS 阳性.结论:双峰驼泪腺的位置与其他动物相似,而形态学特点有差异,这可能与其生活环境有一定关系;组织化学分析结果表明双峰驼主泪腺为混合性腺,第三眼睑上腺和哈氏腺主要为浆液腺.     

Primary adenocarcinoma of the renal pelvis with special reference to histochemical observations

A case of adenocarcinoma of the renal peivis is presented. The patient was an 84-year-old man suffering from longstanding right-sided nephrolithiasis. Surgical resection of the right kidney revealed adenocarcinoma with slight stromal invasion. A tubulovillous adenoma, which was morphologically similar to an adenoma of the large Intestine, was also found adjacent to the adenocarcinoma. The pelvic epithelium neighboring the lesion revealed Intestinal metaplasla. Histochemical studies revealed that the tumor In the patient and adenocarcinomas or adenomas of the large intestine have similar properties of cytoplasmic mucin. These findings suggest that the epithelium with intestinal metaplasia may have developed into the adenoma and flnally transformed into the adenocarclnoma. In addition, only tumor cells with severe atypia, most of which morphologically corresponded to adenocarcinoma, demonstrated positive nuclear staining for anti-p53. This suggests that p53 may play an important role In the malignant transformation of adenomas into adenocarcinomas, as is the case in the large intestine.     

Morphological observations on the contact-induced lysis of target cells

Interactions in tissue culture of sensitized C57BL spleen and DBA/2 mastocytoma cells have been studied by microcinematography, electronmicroscopy and light microscopy. Motile lymphocytes with their characteristic hand mirror shape move on the surface membrane of the target cells, establishing a close contact within a few minutes. As seen by electron microscopy and equidensitometry, the contact between the cells is very firm, leading to damage of the target cell membrane while leaving the effector cell intact. Analysis of time-lapse cinematography shows that one motile lymphocyte has the capacity to lyse more than one target cell, a phenomenon which may account for the highly efficient surveillance mechanism in vivo. The role of soluble factors and the importance of the lymphocytic uropod in cellular interactions are discussed.