Morphology and histology of tarsal glands in bumble bees of the genera Bombus, Pyrobombus, and Megabombus

1991 ◽  
Vol 69 (4) ◽  
pp. 866-872 ◽  
Author(s):  
A. Pouvreau
Keyword(s):  
Smooth Endoplasmic Reticulum ◽  
Ventral Surface ◽  
Bumble Bees ◽  
Basal Region ◽  
Apical Surface ◽  
Tarsal Gland ◽  
Glandular Cells ◽  
Pinocytotic Vesicles ◽  
Secretory Products ◽  
Tarsal Glands

The last tarsal segment and pretarsus of adult bumble bees are described. The tarsal gland on the fifth tarsomere of each leg in all individuals of a colony consists of simple glandular epithelium surrounding a reservoir in which its secretory products accumulate. Movement of the pretarsus in and out of the fifth tarsomere helps to discharge the secretion of the gland onto the ventral surface of the arolium. Study of the fine structure of the glandular cells reveals the presence of cytoplasmic organelles involved in secretion. The apical surface of the cells bears numerous microvilli associated with a smooth endoplasmic reticulum. Ergastoplasm is mainly located in the basal region. The spherical or ovoid nucleus is generally located basally and the cytoplasm contains uniformly distributed Golgi complexes, ribosomes which vary in number from one area to another, more or less electron-dense multivesicular bodies, mitochondria, and pinocytotic vesicles and coated vesicles in the cytoplasm of the apical area. Interdigitations and desmosomes contribute to the cohesion of cells within the epithelium. The tarsal gland of bumble bees is compared with that of other insects, and the function of its secretion is considered.

scholarly journals The cell coat of the sensory and supporting cells of the rainbow trout saccular macula as demonstrated by reaction with ruthenium red and tannic acid.

1990 ◽  
Vol 38 (11) ◽  
pp. 1615-1623 ◽  
Author(s):  
K M Khan ◽  
J S Hatfield ◽  
D G Drescher
Keyword(s):  
Rainbow Trout ◽  
Tannic Acid ◽  
Ruthenium Red ◽  
Sensory Cells ◽  
Surface Coat ◽  
Basal Region ◽  
Apical Surface ◽  
Luminal Surface ◽  
Supporting Cells ◽  
Cell Coat

The surface of most cells is covered by glycoconjugates. The composition and thickness of the surface coat varies among different cell types. The purpose of the present study was to demonstrate the presence of and to characterize the cell coat surrounding the cells in the saccular macula of the rainbow trout. Tissues were fixed in Karnovsky's fixative containing either ruthenium red (0.5, 1, or 2%) or tannic acid (1, 2, or 4%). The apical surface of the sensory and supporting cells reacted with both agents. Varying the concentration of the compounds within a certain range did not significantly affect the degree of tissue staining. Whereas ruthenium red staining was distributed evenly along the luminal surface of the epithelium and along the length of the stereocilia, tannic acid formed electron-dense clumps on the luminal surface of sensory and non-sensory cells and in the basal region of the macular epithelium. The stereocilia of the sensory cells also exhibited tannic acid-positive, electrondense precipitate, particularly near the distal ends of these processes, while uniform staining of the plasma membrane was seen along their lengths. The results of this study suggest that the trout saccular macula is provided with extracellular microenvironments which may be necessary for functional integrity.

Observations of the organ of bellonci of the shrimp Paratya rasmaniensis Riek (Crustacea : Decapoda : Atyidae) with particular reference to the structure of the onion body cells

1972 ◽  
Vol 20 (3) ◽  
pp. 215 ◽  
Author(s):  
PS Lake ◽  
JE Ong
Keyword(s):  
Lipid Droplets ◽  
Ventral Surface ◽  
Terminal Region ◽  
Basal Region ◽  
High Concentration ◽  
Ciliary Process ◽  
Dense Granules ◽  
Colloidal Material ◽  
Connective Tissue Sheath ◽  
Outer Plasma Membrane

The organ of Bellonci of P. tasmaniensis is near the posterior ventral surface of the eyestalk and adjacent to the medulla externa. It is surrounded by a connective tissue sheath and contains lightly staining cells and onion bodies. There is a lumen with colloidal material. Histochemical observations reveal that the onion bodies are proteinaceous, with some lipid and carbohydrate also present. Glycoprotein appears to exist in the cells, while the colloidal material contains carbohydrates and acid mucopolysaccharides. The onion body cells may each be divided into three regions, the basal region, the terminal region, and the onion body. The basal region contains the nucleus, microbodies, golgi complexes, phaosomes, and 4004 electron-dense granules. The terminal region is notable for its high concentration of mitochondria and for its folded outer plasma membrane. From the terminal region, a ciliary process with a poorly defined 9+2 fibril arrangement arises. This structure expands into a bulbous process which then gives rise to lamellae. The lamellae are folded into an oval structure which constitute the onion body. The lamellae may contain mitochondria, lipid droplets, and lysosome-like bodies. The lamellate form of the onion bodies may be transformed into a vesiculated form, cyclically. It is suggested that the organ of Bellonci of P. tasmaniensis is a photoreceptor organ. It also appears to be an active secretory organ.

scholarly journals THE FINE STRUCTURE OF GIARDIA MURIS

1966 ◽  
Vol 29 (2) ◽  
pp. 317-332 ◽  
Author(s):  
Daniel S. Friend
Keyword(s):  
Fine Structure ◽  
Osmium Tetroxide ◽  
Smooth Endoplasmic Reticulum ◽  
Dorsal Surface ◽  
Ventral Surface ◽  
Cell Periphery ◽  
Adhesive Disc ◽  
Medial Surfaces ◽  
Dorsal Portion ◽  
Giardia Muris

Giardia is a noninvasive intestinal zooflagellate. This electron microscope study demonstrates the fine structure of the trophozoite of Giardia muris in the lumen of the duodenum of the mouse as it appears after combined glutaraldehyde and acrolein fixation and osmium tetroxide postfixation. Giardia muris is of teardrop shape, rounded anteriorly, with a convex dorsal surface and a concave ventral one. The anterior two-thirds of the ventral surface is modified to form an adhesive disc. The adhesive disc is divided into 2 lobes whose medial surfaces form the median groove. The marginal grooves are the spaces between the lateral crests of the adhesive disc and a protruding portion of the peripheral cytoplasm. The organism has 2 nuclei, 1 dorsal to each lobe of the adhesive disc. Between the anterior poles of the nuclei, basal bodies give rise to 8 paired flagella. The median body, unique to Giardia, is situated between the posterior poles of the nuclei. The cytoplasm contains 300-A granules that resemble particulate glycogen, 150- to 200-A granules that resemble ribosomes, and fusiform clefts. The dorsal portion of the cell periphery is occupied by a linear array of flattened vacuoles, some of which contain clusters of dense particles. The ventrolateral cytoplasm is composed of regularly packed coarse and fine filaments which extend as a striated flange around the adhesive disc. The adhesive disc is composed of a layer of microtubules which are joined to the cytoplasm by regularly spaced fibrous ribbons. The plasma membrane covers the ventral and lateral surfaces of the disc. The median body consists of an oval aggregate of curved microtubules. Microtubules extend ventrally from the median body to lie alongside the caudal flagella. The intracytoplasmic portions of the caudal, lateral, and anterior flagella course considerable distances, accompanied by hollow filaments adjacent to their outer doublets. The intracytoplasmic portions of the anterior flagella are accompanied also by finely granular rodlike bodies. No structures identifiable as mitochondria, smooth endoplasmic reticulum, the Golgi complex, lysosomes, or axostyles are recognized.

scholarly journals Expression of Trefoil factor family peptides in the nasal allergic mucosa

2012 ◽  
Vol 50 (4) ◽  
pp. 408-416
Author(s):  
N. Miyahara ◽  
T. Ishino ◽  
T. Kono ◽  
K. Go ◽  
S. Takeno ◽  
...  
Keyword(s):  
Nasal Mucosa ◽  
Mucosal Healing ◽  
Trefoil Factor ◽  
Quantitative Real Time Pcr ◽  
Human Respiratory Tract ◽  
Human Nasal Mucosa ◽  
Mrna Transcripts ◽  
Glandular Cells ◽  
Trefoil Factor Family ◽  
Secretory Products

Objective: Trefoil factor family peptides (TFFs) are the secretory products of mucous cells and are closely associated with mucins. TFFs appear to be important in mucosal healing processes. Although TFF1/3 are expressed in the human respiratory tract, their role in the nasal mucosa is not thoroughly understood. We investigated the association between TFFs and mucins and the role TFFs in the human nasal mucosa. Material and methods: Patients undergoing turbinectomy were included and it was determined whether patients had nasal allergies or not. The localization of TFF1/3, MUC5AC/5B expression was investigated using immunohistochemistry. The levels of the mRNA transcripts were examined using quantitative real-time PCR. Results: TFF1/3 had a similar pattern of localization in epithelial goblet cells and submucosal glandular cells. TFF1/3 co-localized with MUC5AC in the epithelium, and co-localized with MUC5B in the epithelium and the submucosal glandular cells. The levels of TFF1/3 and MUC5B mRNA in allergic patients were significantly increased. Conclusion: Our results suggest that TFF1/3 may associate with MUC5AC and MUC5B in the nasal mucosa, and that up-regulation of TFF1/3 and MUC5B may play an important role in the clinical condition of the nasal allergic mucosa.

Structure of the noncuticular simplex of the internal male reproductive tract of Calpodes ethlius (Hesperiidae, Lepidoptera)

1982 ◽  
Vol 60 (6) ◽  
pp. 1184-1201 ◽  
Author(s):  
J. Lai-Fook
Keyword(s):  
Cellular Structure ◽  
Secretory Cell ◽  
Reproductive Tract ◽  
Secretory Cells ◽  
Apical Region ◽  
Apical Surface ◽  
Male Reproductive Tract ◽  
Circular Layer ◽  
Secretory Products ◽  
Longitudinal Layer

The ductus ejaculatorius simplex (simplex) of the reproductive tract of the adult male of Calpodes ethlius is separated by distinct constrictions into seven segments, varying in length from 0.24 to 19.3 mm and totalling 4 cm. Two of the segments, S1 and S5, are further divisible into three and two parts, respectively, on the basis of either cellular structure or secretory products. The most distinctive region is the most anterior one which is made up of two distinctly different cells, one a merocrine secretory cell which resembles the cells of all other regions, and the other an apocrine secretory cell whose highly modified apical region is sloughed upon copulation. All segments are surrounded by two layers of muscle, a thin, inner circular layer and a more robust, outer longitudinal layer, which are supplied with tracheoles and nerves. Tracheoles also penetrate the epithelium of segment seven. The merocrine secretory cells of all segments are similar in that they all have well-developed endoplasmic reticulum, numerous Golgi and mitochondria, and a microvillate apical surface. Nonetheless, the cells of each segment are distinguished by some feature of either their structure or their secretions.

scholarly journals Attachment devices and the tarsal gland of the bug Coreus marginatus (Hemiptera: Coreidae)

Zoomorphology ◽  
2021 ◽  
Vol 140 (1) ◽  
pp. 85-102
Author(s):  
Manuela Rebora ◽  
Gianandrea Salerno ◽  
Silvana Piersanti ◽  
Elena V. Gorb ◽  
Stanislav N. Gorb
Keyword(s):  
Fine Structure ◽  
Dorsal Surface ◽  
Ventral Surface ◽  
Hydraulic Pressure ◽  
Capillary Suction ◽  
Gland Cells ◽  
Tarsal Gland ◽  
Fluid Production ◽  
Adhesive Fluid ◽  
Attachment Devices

AbstractThe present ultrastructural investigation using scanning and transmission electron microscopy as well as light and fluorescence microscopy describes in detail the attachment devices and tarsal gland of the bug Coreus marginatus (L.) (Hemiptera: Coreidae). In particular, the fine structure of pulvilli reveals a ventral surface rich with pore channels, consistent with fluid emission, and a folded dorsal surface, which could be useful to enhance the pulvillus contact area during attachment to the substrate. The detailed description of the tarsal gland cells, whose structure is coherent with an active secretory function, allows us to consider the tarsal gland as the plausible candidate for the adhesive fluid production. Scolopidia strictly adhering to the gland cells are also described. On the basis of the fine structure of the tarsal gland, we hypothesise a fluid emission mechanism based on changes of the hydraulic pressure inside the gland, due to the unguitractor tendon movements. This mechanism could provide the fluid release based on compression of the pad and capillary suction, as demonstrated in other insects. The data here reported can contribute to understanding of insect adhesive fluid production, emission and control of its transport.

Choroid Plexus Papillomas: an Ultrastructural Study

1970 ◽  
Vol 28 ◽  
pp. 214-215
Author(s):  
John L. Beggs ◽  
John D. Waggener ◽  
Philip L. Carter
Keyword(s):  
Choroid Plexus ◽  
Single Layer ◽  
Communicating Hydrocephalus ◽  
Basal Region ◽  
Apical Surface ◽  
State University ◽  
Arizona State University ◽  
Intercellular Spaces ◽  
Ultrastructural Studies ◽  
Choroid Plexus Papillomas

Choroid plexus papillomas make up about 0. 5 per cent of brain tumors and are of particular interest in that they are frequently associated with obstructive and communicating hydrocephalus.Histologically, normal choroid plexus consists of many villi composed of cores of highly vascular connective tissue with an overlying single layer of cuboidal or low columnar epithelium. Ultrastructural studies (Beggs, Thesis, 1969, Arizona State University) of normal choroid plexus epithelium show the microvilli at the apical surface to be irregular in shape and size. In addition to microvilli at the apical surface, occasional cilia are present. The basal region is characterized by having numerous infoldings and large intercellular spaces.

Memoirs: The Atrium and the Prostate Gland in the Microdrili

1925 ◽  
Vol s2-69 (275) ◽  
pp. 399-444
Author(s):  
H. R. MEHRA
Keyword(s):  
Vas Deferens ◽  
Prostate Gland ◽  
Ventral Side ◽  
Tubifex Tubifex ◽  
Muscle Fibres ◽  
Atrial Wall ◽  
Sperm Duct ◽  
Prostate Cells ◽  
Glandular Cells ◽  
Secretory Products

1. The atrium in two species of the Naididae is described. The prostate in Nais elinguis forms the wall of the vas deferens; in Slavina punjabensis it covers the atrium. The atrium is formed as an ectodermal invagination and always occupies a position at the end of a short vas deferens. The atrial epitbehium in the sexually mature Stylaria lacustris and Slavina punjabensis is replaced by the prostatic secretion which passes through it ; it is not really composed of glandular cells as has been so far considered. 2. The prostate cells in the Naididae may surround the atrium or the vas deferens or both. The cells appear to penetrate into the muscle-fibres of the atrial wall in order to directly communicate with the atrial epithelium. They also become more or less completely changed in the late stage of sexual maturity into the secretion and lose their identity. The prostate cells are peritoneal in origin. The prostate may be absent or rudimentary in some species of the Naididae. 3. Various stages in the development of the sperm-duct in Tubifex barbatus are described. The atrium is shown to be a part of the vas deferens and hence mesodermal in origin. The prostate lies near the seminal funnel on the ventral side of the vas deferens just above the ovary ; in the early condition it is a deeply stained mass of nuclei with a little cytoplasm and continuous with the peritoneal layer of the vas deferens in front and behind. 4. The atrium and the prostate in Tubifex tubifex and Limnodrilus udekemianus are described. The prostate is peculiar in the species of the Tubificidae iuvestigated in the fact that the secretion of a fibrillar appearance forms the centre of the gland, while the cells occupy the periphery. The fibrillar secretion flows into the atrial epithelium, through a regular passage or opening where the muscular wall is absent. This appearance probably led previous workers to suppose that the prostate cells open by long ductules at the point of communication with the atrium. There is no evidence whatsoever that the prostate arises as an outgrowth from the atrial epithelium ; on the other hand it is obviously peritoneal in origin. 5. The cytoplasm in the prostate cells is basophil as distinguished from the acidophil central part with the secretion, and in Tubifex tubifex during the advanced condition of the gland generally contains basophilous granules, which pass with the fibrillar secretion as secretory products into the atrium. The prostate cells in the advanced sexual condition lose their structure and do not show mitochondria. 6. The atrial epithehium in all the Species of the Tubificidae considered is not composed of gland-cells. It is on account of the prostatic secretion, which passes through it into the atrial lumen, that it degenerates and its cells break down. 7. The prostatic secretion in the Naididae and Tubificidae appears as a fluid of thick consistency. Its function is mainly to cement or unite sperms received in the atrium. It does not contain mucin, but in sections of Tubifex tubifex prepared according to the Mann-Kopsch method the central conducting part of the gland and a portion of the atrial wall show the presence of a large amount of fat, mainly olein, or some lipoid substance, which reduces osmium tetroxide, and thus becomes deep black like the dictyosumes of the Golgi apparatus. 8. The homologies of the atrium and the prostate are briefly discussed in the various families of the Microdrili. 9. Peculiar features in the structure of the vas deferens in Tubifex tubifex and Limnodrilus udekemianus are described.

Morphology of salp chain communication

1980 ◽  
Vol 210 (1181) ◽  
pp. 549-558 ◽  
Keyword(s):  
Epithelial Cells ◽  
Smooth Endoplasmic Reticulum ◽  
Ventral Surface ◽  
The Other ◽  
Test Material ◽  
Sensory Cells ◽  
Light Microscope Level ◽  
Physiological Properties ◽  
Epithelial Layers ◽  
Specialized Region

The plaque consists on one side of a small button of modified epithelial cells (plate 1, 5 and 6) and on the other of a small group of sensory cells, which are less conspicuous than the button cells. At the light microscope level, the button cells can be seen to form a sort of small button or mushroom protuding from the epithelium of the plaque (plate 1, 11 and 12; figure 2) into the test material separating the two epithelial layers. Opposite this button are a group of sensory cells, the axons of which pass to the brain shrouded in the bases of the epithelial cells (plate 1, 8 and 9). The arrangement of the button cells and opposing sensory cells is a constant one, so that, on a single zooid, one of the pair of plaques joining it to an adjacent zooid has a group of sensory cells, the other (the non-innervated plaque), a group of button cells. The plaques at the outer ends of the horns are innervated, as are those near the horn bases, while those on the ventral surface and at the inner end of the horns are not innervated, and have the button cells. In consequence of this, it is a simple matter to separate one or other of the plaques joining two zooids to investigate their physiological properties (Anderson & Bone 1980). Fedele (1920) first described the sensory cells of the attachment plaques, but he supposed that they occurred at both sides in each plaque. In fact, they lie only on one side of the plaque, as described above, and this asymmetry has important consequences for the way in which the system operates. Apart from the specialized region of the plaque, where these cells are found, the plaque is symmetrical, and the two epithelial layers are some 5 μm apart, separated by test material (plate 1, 7). The epithelial cells are flattened (like those of the outer epithelium outside the plaques), and are some 2–5 pm thick (plate 2, 1). They contain an extensive smooth endoplasmic reticulum, mitochondria with tubular cristae, flattened nuclei, and occasional vesicles of various sizes

scholarly journals FINE STRUCTURE OBSERVATIONS OF THE UPTAKE OF INTRAVENOUSLY INJECTED PEROXIDASE BY THE RAT CHOROID PLEXUS

1967 ◽  
Vol 15 (3) ◽  
pp. 160-165 ◽  
Author(s):  
NORWIN H. BECKER ◽  
ALEX B. NOVIKOFF ◽  
H. M. ZIMMERMAN
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Cerebrospinal Fluid ◽  
Choroid Plexus ◽  
Smooth Endoplasmic Reticulum ◽  
Multivesicular Bodies ◽  
Adult Rats ◽  
Dense Bodies ◽  
Pinocytotic Vesicles ◽  
Membrane Bound

The uptake by the choroid plexus of adult rats of intravenously injected horseradish peroxidase has been investigated by electron microscopy. Within 4 min, the injected protein passes the capillary and is rapidly distributed through extracellular space and choroidal cells. Peroxidase enters the choroidal cells within coated vesicles which act as pinocytotic vesicles. At 15 min, peroxidase activity is present in numerous membrane-bound vesicles, multivesicular bodies, dense bodies and what appear to be segments of smooth endoplasmic reticulum. None of the peroxidase-containing organelles is seen to empty to the ventricular surface. Egress of the extracellular peroxidase into the cerebrospinal fluid is apparently blocked by apical zonulae occludentes between the choroidal cells.

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