The ultrastructure of sensory corpuscles in the skin in the hedgehog snout

The ultrastructure of sensory nerve endings was examined in the snout skin in 3 adult hedgehogs (Erinaceus europaeus). The material was taken intravitally under total anaesthesia and processed in a usual way for the electron microscopy. The corpuscles were evaluated in the individual sections and series sections made through the whole corpuscle. In the superficial layers of the dermis simple sensory corpuscles and free endings were found. The simple sensory corpuscles can be divided into three types. a) Corpuscles containing a greater number of lamellae in the inner core, the lamellae are arranged regularly and are separated by two opposite clefts. The capsule is formed by only several lamellae undoubtedly of fibrocytic origin. b) Corpuscles containing a smaller number of wider lamellae in the inner core situated often at random. The clefts are also irregular and are often closed in the superficial layers of the inner core. The capsule is quite simple mostly formed by a single lamella of fibrocyte which often fails to form a continuous coat of the corpuscle. c) The third type is typical of its inner core being formed by few lamellae arranged irregularly. These corpuscles have no connective tissue capsule and are separated from the environments only by the basement membrane of superficial lamellae of the inner core. The corpuscles of the second type resemble considerably the developmental stages of simple sensory corpuscles as described in the literature in the cat. They are the same in size or smaller than the corpuscles of the first type. The free nerve endings occurred in two forms. a) Flattened (lanciform) nerve terminals. The axon is rich in mitochondria. The sides of the flattened terminal is lined with one to three wide lamellae while the axon reaches as far as the surface of the formation which is covered only with the basement membrane. b) Typical free endings rich in mitochondria which are embedded in the cytoplasm of Schwann cells or occasionally are covered only with the basement membrane. The lanciform endings which are not linked up with the hairs here may represent a transition from free endings to simple sensory corpuscles.     

A histological and anatomical profile of pacinian corpuscles from Dupuytren's contracture and the expression of nerve growth factor receptor

The etiology of Dupuytren's disease is unknown. The causes of the fibroplastic response of nodules, fibrosis of cords, and prominence of pacinian corpuscles are not evident. Histological and immunohistology differences in pacinian corpuscles from the hands of five patients with Dupuytren's disease compared with 17 Dupuytren's-free patients are presented. Histological sections of pacinian corpuscle specimens were stained with hematoxylin and eosin and immunostained for nerve growth factor receptor. The length and width of intact pacinian corpuscles were measured, and the number of layers within each corpuscle was counted and recorded. Grossly, the pacinian corpuscles from Dupuytren's patients were larger and more numerous compared with those from unaffected patients. When measured microscopically, the pacinian corpuscles from Dupuytren's diseased fascia were significantly larger (2.0 x 1.1 mm) compared with controls (1.5 x 0.78 mm). The pacinian corpuscles from Dupuytren's-affected patients had significantly more layers (64 +/- 14) compared with those from control patients (40 +/- 9). Nerve growth factor receptor staining of pacinian corpuscles from patients affected with Dupuytren's disease showed greater intensity and more area stained compared with unaffected controls. It is suggested that nerve growth factor may be involved in the increased size of pacinian corpuscles in Dupuytren's-affected fascia. It is proposed that the cellular outgrowth from pacinian corpuscles may generate the cells that develop into Dupuytren's nodules.     

Counting renal corpuscles in tissue sections

Two stereologic methods of counting renal corpuscles in tissue sections were evaluated. Weibel's stereologic method was found to be an accurate and efficient means of determining the number of corpuscles in normal and diseased kidneys. Weibel's method was preferred over the stereologic method of Elias and Hennig because the former is independent of tissue section thickness and is sensitive to variation in corpuscular size. A modification of Weibel's method eliminated the need for an additional point-counting procedure to determine the volumetric fraction of corpuscles in a kidney. The modification made use of previously completed measurements to calculate the area fraction of corpuscles and then substituted this value for the volumetric fraction of renal corpuscles.     

Epithelial cell heterogeneity in mammalian thymus: Monoclonal antibody to high molecular weight keratins exclusively binds to Hassall''s corpuscles

Summary Hassall's corpuscles represent a subset of medullary thymic epithelial cells whose origin and function within the thymus still remain largely unknown. The present study shows that Hassall's corpuscles can be defined by their intracellular content in specific keratin subunits. Two monoclonal anti-keratin antibodies were used: KL1, directed to high molecular weight keratins, and KL4, specific for high and medium molecular weight polypeptides.In vivo, KL1 exclusively binds to Hassall's corpuscles of five mammalian species including mouse, rat, guinea-pig, rabbit and pig. Thus KL1 appears as an exclusive marker of Hassall's corpuscles in a large number of mammals.In vitro, thymic epithelial cells gave rise in certain species to Hassall's corpuscles. In contrast to itsin vivo reactivity, KL1 never labelled Hassall's corpuscles developedin vitro. These data strongly support the following conclusions: (1) Hassall's corpuscles derive from medullary epithelial cells; (2) they represent advanced stages of thymic epithelial maturation; (3) thymic epithelial cell differentiation is impairedin vitro. Furthermore, this study provides additional evidence that thymic epithelium heterogeneity reflects different stages in epithelial maturation.     

Corpuscular bodies in the palate of the rat. 1. Morphology and distribution

The morphology and the frequency distribution of corpuscular bodies in the palate was studied in rats using light and electron microscopy. The study extended from the day of birth through 180 days after birth. The corpuscles appeared as round (diameter 35-50 microns) to ovoid (width 40-60 microns, height 60-90 microns) bodies intercalated within the epithelium of the incisal papilla and the soft palate. A subepithelial nerve plexus surrounded the base of a corpuscle. For types of cells were identified within the corpuscle: basal, type I (dark), type II (pale) and type III cells. Some cells bore microvilli which protruded through a pore into the oral cavity. Numerous nerve endings terminated in close relation to the latter three types of cells. Two distinct types of membrane specializations were found representing axosomatic and axo-axonal contacts. On morphological grounds we interpret the structures described as receptors of taste. At birth, a mean total of 21 corpuscles was observed in the entire palate of which 31% was located on the incisal papilla and 68% was found in the soft palate. During the first 2 weeks (16 days) of postnatal life, the number of corpuscles increased. Thereafter, a significant decrease in corpuscle number occurred with increasing age. We speculate that the corpuscles are associated with the learning process of food selection.     

Macrophages in Pacinian corpuscles

The presence of macrophages in the outer bulb region of mouse, monkey and human Pacinian corpuscles was demonstrated by light and electron microscopy. In the normal, nontreated, Pacinian corpuscles, a few particular cells were located in the spaces between lamellae of the outer bulb. These cells contained numerous vesicles and vacuoles, and various cytoplasmic processes. When horseradish peroxidase (HRP) was injected locally or systemically, many HRP-positive cells, which were considered to be similar to the particular cells described above, were found in the outer bulb region of the corpuscles. Electron microscopy revealed that these cells contained HRP in vesicles and vacuoles, suggesting that they were macrophages vigorously taking up exogenous HRP. Macrophages in the Pacinian corpuscles are considered to work as scavengers to keep the inner environment of the corpuscles clear and constant with regard to its macromolecular content.     

Changes in the renal corpuscles during early postnatal ontogeny of the rat (stereologic analysis)

Kidneys of 60 white rats at the age of 1-45 days of postnatal life have been investigated. Increase in size of the renal corpuscles during the developmental process is accompanied with certain changes in the form and variability of volumes in the structures studied. During early postnatal period, against the background of linear increase in the size of the renal corpuscles, the parameters of variability in volumes, form and in the total number of the renal corpuscles in the organ change non-linear. Stabilization moment of the total number (11-14 days) on the 8th-10th day outgoes that for the parameters of the form and variability of the renal corpuscle volumes.     

Incorporation of calcium into the soft tissues and calcareous corpuscles of larval Taenia taeniaeformis.

Larval Taenia taeniaeformis in vivo accumulates 45Ca2+ in soft tissues and calcareous corpuscles. Radioactivity was demonstrable in the corpuscles six months after a single dose of 45Ca2+ was administered to the host by means of a stomach tube. Ca2+ also was taken up by isolated larvae. Accumulation in vitro was more rapid then in vivo and was correlated with the external Ca2+ concentration. Temperature variation, oxygen availability, and metabolic inhibitors had little effect on the Ca2+ uptake, indicating that active transport of Ca2+ is unlikely in this parasite. Variations in the external Pi concentrations had no effect on Ca2+ accumulation or on its distribution. Addition of 5% CO2 increased the uptake of Ca2+ by the calcareous corpuscles under anaerobic conditions. Radioactivity from NaH14CO3 also was accumulated in soft tissues and corpuscles of T. taeniaeformis. Assuming that the 14C taken up by the corpuscles was in the form of 14CO3(2-), the ratio of Ca2+ to CO3(2-) accumulation in the corpuscles approximates the ratio of these constituents in dolomite: CaMg(CO3)2.     

Thymic medullary structures: Microscopical picture of the thymic medullary structures in children with congenital heart defects

The aim of this work is to describe the structure of the thymus, especially its medullary part, in children with congenital heart defects. It is known that development of the thymus and the heart is also influenced by neural crest cells. During the early development of the heart and the thymus cells proliferate and migrate to their primordia. It is known that inadequate cephalic neural crest contribution during development of pharyngeal pouch derivatives results in defective organogenesis of the face, the thymus, parathyroid glands and also the heart. We studied the structure of the thymus in children with congenital heart defects from 0 to 12 years of life at light microscopic and electron-microscopic levels. Thymuses of the patients were surgically removed in the Children’s Cardiocenter in Bratislava. The results of our study confirmed the differences in the medullary structures of thymuses with chosen diagnoses. Hassall’s corpuscles in the thymic medulla were various in size and also in structure and number. The special structures of the thymic medullary region in children with ventricular septal defects and defects of outflow of the heart were big cystic Hassall’s corpuscles. In comparison with a size of Hassall’s corpuscles in normal thymuses the size of Hassall’s corpuscles in studied thymuses suprisingly ranged between 100–250 μm.     

Relationships between the amount of saliva and medications in elderly individuals

Gerodontology 2010; doi: 10.1111/j.1741‐2358.2009.00358.x
Relationships between the amount of saliva and medications in elderly individuals Objective: To investigate medications that are related to volume of saliva in the elderly. Background data: In the elderly, many cases of mouth dryness may represent side effects of medication. Materials and methods: The volume of unstimulated saliva was measured for 30 s (cotton roll test), and with stimulation for 3 min (gum test) in 368 subjects 79–80 years old (177 men, 191 women). Medications were investigated using subject’s medication notebooks. Results: Mean volumes of unstimulated and stimulated saliva were 0.14 ± 0.13 and 4.30 ± 2.54 ml respectively. Significant differences were seen between gender and mean volume of saliva. The volume of unstimulated saliva was 0.16 ± 0.15 ml for men and 0.11 ± 0.10 ml for women. The volume of stimulated saliva was 4.99 ± 2.67 ml for men and 3.67 ± 2.25 ml for women. The percentage of subjects taking medication was 64.7% (238/368). Mean number of medications was 2.08 ± 2.26, with no significant difference with gender (2.01 ± 2.37 for men, 2.16 ± 2.16 for women). In a stepwise multiple regression analysis with volume of saliva as the objective variable and number of drugs by category as explanatory variables, significant explanatory variables in addition to gender and number of medications were blood‐coagulating agents, Ca antagonists and peptic ulcer drugs for volume of unstimulated saliva, and diabetes medications and peptic ulcer drugs for volume of stimulated saliva. Conclusion: These findings suggest that differences exist between gender in volume of saliva for elderly individuals, and that the volume of saliva is affected by the number and type of medications.     

Pancreatoblastoma. A case report with special emphasis on squamoid corpuscles with optically clear nuclei rich in biotin

BACKGROUND: Pancreatoblastoma (PBL) is a rare neoplasm that generally occurs in the pediatric age group and shows unique histopathology, including squamoid corpuscles that may contain tumor cells with optically clear nuclei (OCN) rich in biotin. In the English-language literature there have been two reports on the cytology of PBL, but neither of them refers to the cytologic features of squamoid corpuscles. CASE: A 3-year-old boy with nausea and general fatigue was referred to our center. Imaging studies showed an approximately 7.5-cm, left-sided abdominal mass and multiple metastases in the lung. The abdominal mass was biopsied, and its histology showed solid cellular nests with occasional acinar differentiation and squamoid corpuscles. Imprint cytology of the biopsied sample displayed cellular epithelial nests with focal acinar structures and foci composed of larger cells with a low nuclear/cytoplasmic ratio. These foci contained a few tumor cells with biotin-rich OCN and were determined to be squamoid corpuscles. CONCLUSION: Detection of occasional squamoid corpuscles with biotin-rich OCN can be useful in making a diagnosis of PBL on cytologic samples.     

家鸽Herbst小体对振动的反应特征

鸟类的Herbst小体是一种形态特殊的感觉性神经末梢器官.本文利用电生理学方法,研究了家鸽腿部胫骨-腓骨之间的Herbst小体对振动刺激的反应特征.这种小体对振动刺激非常敏感,当振动频率在600—800赫时,它们有反应的最低阈值约为0.3微米.不同的Herbst小体的反应阈值与频率的关系曲线表明:这种小体具有明显的带通滤波的特征,对振动反应的最佳频率范围为400—1000赫.在适宜频率、超阈值强度的振动刺激下,Herbst小体能以1:1的方式作出反应,即相对于每次正弦波振动刺激都有一个锁相的神经脉冲产生.在背根脊神经节内的细胞外记录表明:对振动敏感的神经节细胞具有和Herbst小体完全相似的反应特征.     

The effect of long-term denervation on the ultrastructure of Pacinian corpuscles in the cat

Summary The ultrastructure of Pacinian corpuscles of the cat located in the crural region and innervated by the interosseous nerve was studied 1 to 14 months after denervation. Both the Pacinian inner core and capsule remained well preserved one month after denervation. However, the denervated inner cores underwent progressive atrophy and wasting, which resulted in a gradual reduction of the amount of inner-core cells and lamellae, widening of interlamellar clefts, formation of empty spaces in the axial region and a considerable increase in the number of collagen fibrils. In spite of the wasting, the inner core still survived 14 months after denervation, but at least half of its volume became occupied by collagen fibrils which surrounded the remaining inner-core cells and lamellae. Collagen fibrils assembled in the denervated core were markedly thinner than those found in the capsule, as is also the case in normal Pacinian corpuscles. In the capsule, discrete focal degeneration, occasional pyknosis of the innermost capsular cells and macrophage infiltration were observed from the first month after nerve section onward, but the number of capsular layers remained within the normal range (30–40) up to 14 months after denervation.     

Distribution of sensory receptors in the flexor carpi radialis muscle of the cat

The structures and distribution of encapsulated muscle receptors were examined in serial transverse sections of flexor carpi radialis in the adult cat. Four types of receptors (muscle spindles, Golgi tendon organs, paciniform, and Pacinian corpuscles) were identified. Their structures resembled those encountered in other limb muscles. Pacinian corpuscles were rare and occurred only in the external fascial coat of the muscle near its origin. The other three receptor types were distributed in an uneven but consistent pattern throughout the muscle. As noted previously (Gonyea and Ericson, '77), spindles were largely confined to a deep muscle region comprising less than 20% of the muscle volume, located directly between the long tendon of origin and the tendon of insertion. This region contains the largest proportion of type SO muscle fibers (Gonyea and Ericson, '77). Tendon organs and paciniform corpuscles were concentrated along the tendons that lined the spindle-rich muscle region. This region appeared to be composed of extrafusal fibers that were shorter and of more oblique pinnation than those in other regions. The localization of muscle receptors to the "oxidative" core of the muscle in its direct line of pull may have functional implications for afferent input to the spinal cord which are discussed. In addition, the possibility is raised that there are more paciniform corpuscles in flexor carpi radialis (and possibly other muscles) than previously thought.     

Fluoride resistant acid phosphatase activity in pacinian corpuscles of the cat mesentery. Light microscope

Fluoride-resistant acid phosphatase (extralysosomal) activity has been investigated in Pacinian sensory corpuscles from cat's mesentery. The activity was found in the innermost and intermediate layers of the capsular system, but it is not possible to establish its exact localization. The central axon and the inner core were FRAP negative. The authors discuss the possible functional significance of FRAP activity in sensory corpuscles.     

Ultrastructure of sensory nerve terminals in the penis in green monkey (Cercopithecus aethiops sabaeus).

Tje paper describes the ultrastructure of axons in the endings of various types from the corium in the glans penis in green monkey. In the Meissner's endings the axons are mostly completely enveloped in the plasma of Schwann cells. They contain numerous mitochondria which are partially vacuolated or are quite converted into vacuoles. Next, there are pseudomyelinated figures, light vesicles and further organelles. In the papillar simple glomerular endings with accumulation of Schwann cells there are axons irregular in shape, eccentrically placed in the plasma of Schwann cell, rounded smaller axons either completely or partially surrounded by the plasma of Schwann cell and finally axons with a concentric system of lamellae up to four in number, In the complicated glomerular endings the axons vary in appearance and are enveloped in one to five lamellae of Schwann cells, which is typical of those formations. About some of these systems there is a sign of a capsule formed by an elongated lamella probably of the perineurium. When the axons are not enveloped in the plasma of Schwann cell, they are covered by the basement membrane. In close neighbourhood of the epidermis so-called free endings forming groups were found. The plasma of Schwann cell covers them either partially or completely or it again forms around them a lamellar system amounting up to four layers. It is noticeable that these axons are very poor in organelles. A comparison of the simple sensory corpuscles in the nose skin in hedgehog, the funtional properties of Meissner's endings and the simple corpuscles results in the view that the complexes having a larger amount of lamellae correspond to an extent to the simple sensory corpuscles ant that the Meissner's endings and the complicated glomerules are probably a morphological and functional equivalent of simple sensory corpuscles in the non-primate mammals and that the gloverular endings may also be the first (developmental) stage of the simple sensory corpuscles.     

Role of Blood Platelets in Haematophagy

RED blood corpuscles (RBC) suspended in saline induce gorging in many haematophagous insects because of their high intrinsic concentration of adenine nucleotides (ANS)^1–6. ANS are bound firmly inside the intact RBC, which raises the question of how they gain egress to contact the chemoreceptor surfaces and induce feeding. It has been suggested that saliva or secretions of the chemoreceptor surfaces act as ANS releasing agents¹. ANS release by haemolysis is discounted by the fact that all RBC found in the gut immediately after feeding are intact. Further, stereoscan electron microscopy of tsetse fly gustatory sensilla does not suggest that they operate by piercing the erythrocytes^7,8. Thus we decided to test the possibility that the chemoreceptors involved in blood identification receive an ANS stimulus from a source associated with, but not within the RBC.     

Morphology, distribution, and density of sensory receptors in the glabrous skin of the cat rhinarium

The sensory organization of the cat rhinarium has been investigated. Individual rete pegs were found to contain a triad of receptors comprising free nerve endings ascending in the peg to terminate in close proximity to the skin surface, a basally situated layer of Merkel corpuscles, and an abundance of encapsulated receptors lying at the base and to one side of the rete peg. Neither the Merkel corpuscles nor the encapsulated receptors were evenly distributed. Merkel corpuscles were more abundant dorsally; ventrally they were fewer and asymmetrically arranged within individual rete pegs. The encapsulated corpuscles were more evenly distributed, but dorsally they were consistently present as encapsulated clusters of up to nine corpuscles.     

An ultrastructural study of the effect of parasitism by larval Schistosoma mansoni on the calcium reserves of the host,Biomphalaria glabrata

Summary The tissues of Biomphalaria glabrata contain three types of calcium cells which can be differentiated by their location and the size and number of their contained corpuscles. X-ray analysis has confirmed the presence of calcium and magnesium in the corpuscles. Molluscs containing the larval stages of Schistosoma mansoni at 40 days post infection show disintegration of the calcareous corpuscles in Type-A calcium cells and erosion of the inner surface of the shell.Deceased     

The measurement of hormones in saliva: possibilities and pitfalls

The easy stress-free, non-invasive nature of saliva collection makes it one of the most accessible body fluids and it is potentially of value in studying normal human physiology as well as pathology. Measurements of salivary hormone levels will usually only be of value if they reflect the plasma level of the hormone and the relationship between the saliva and plasma levels of many hormones have been studied by a number of groups. The measurement of the salivary level is a valuable clinical tool for some hormones (e.g. cortisol, oestriol, progesterone), is of little value for others (e.g. cortisone, dehydroepiandrosterone sulphate, thyroxine, pituitary hormones) and for many others the saliva/plasma relationship is not yet sufficiently understood to assess the value of the salivary measurement. As well as reviewing the state of our knowledge of the salivary concentration of many hormones this review outlines a number of "rules of thumb" concerning the presence of hormones in saliva, their saliva/plasma relationship and the potential usefulness of assays of their salivary concentration.