scholarly journals The structure of elaiophores in Oncidium cheirophorum Rchb.f. and Ornithocephalus kruegeri Rchb.f. (Orchidaceae)

2012 ◽  
Vol 60 (2) ◽  
pp. 9-14 ◽  
Author(s):  
Agata Pacek ◽  
Małgorzata Stpiczyńska
Keyword(s):  
Epithelial Cells ◽  
Oil Production ◽  
Secretory Cells ◽  
Secretory Structures ◽  
Flower Opening ◽  
Starch Grains ◽  
Dense Cytoplasm ◽  
Parenchyma Cells ◽  
Tangential Wall

The shining appearance of the flowers of <i>Oncidium cheirophorum</i> and <i>Ornithocephalus kruegeri</i> results from the presence of lipids on the flower surface. The lipids are produced by elaiophores - secretory structures situated symmetrically at the base of the labellum or upon the callus. In <i>O. cheirophorum</i>, the elaiophores are epithelial type. They consist of one layer of cuboidal secretory cells and subsecretory parenchyma. The thick cuticle covering the outer, tangential wall of epithelial cells becomes distended and wrinkled as secreted oil accumulates beneath its surface. Oil secretion begins at the bud stage and lasts till the end of anthesis, that is 22 days, on average. Pollination does not influence oil production. In <i>O. kruegeri</i>, trichomatous elaiophores are situated on the central part of the callus. Unicellular trichomes project from the epidermis cells. Their outer walls are covered by a thin cuticle. In the dense cytoplasm of the trichomes, small plastids with few starch grains occur, whereas subsecretory parenchyma cells contain amyloplasts with large starch grains and raphides. The oil is already produced at the bud stage, about one week before flower opening, and lasts till the end of anthesis.

scholarly journals The Fine Structure of the Wheat Scutellum During Germination

1972 ◽  
Vol 25 (3) ◽  
pp. 469 ◽  
Author(s):  
JG Swift ◽  
TP O'brien
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
Epithelial Cells ◽  
Light And Electron Microscopy ◽  
Cell Types ◽  
Wall Material ◽  
Cytological Evidence ◽  
Starch Grains ◽  
Parenchyma Cells ◽  
Cytological Changes

The cytological changes that take place in the scutellar epithelium and parenchyma during the first 5 days of germination are described by light and electron microscopy. Within 6 hr small starch grains appear in the plastids of both cell types and the size and number of starch grains increase gradually as germination proceeds. Later in germination starch disappears again from the plastids in the epithelial cells, but large starch grains still remain in the parenchyma cells. The reserves of the protein bodies are hydrolysed and the residual vacuoles undergo extensive coales-cence. Modifications in the appearance of the wall material of the epithelial cells as these cells elongate are illustrated and possible functional bases for these changes are suggested. The cells of the scutellar epithelium show no cytological evidence for their known functions of diastase secretion and nutrient absorption.

scholarly journals Natural Herbal Estrogen-Mimetics (Phytoestrogens) Promote the Differentiation of Fallopian Tube Epithelium into Multi-Ciliated Cells via Estrogen Receptor Beta

Molecules ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 722
Author(s):  
Maobi Zhu ◽  
Sen Takeda ◽  
Tomohiko Iwano
Keyword(s):  
Estrogen Receptor ◽  
Cell Differentiation ◽  
Epithelial Cells ◽  
Fallopian Tube ◽  
Ciliated Cell ◽  
Estrogen Receptor Beta ◽  
Notch Pathway ◽  
Secretory Cells ◽  
Ciliated Cells ◽  
Receptor Beta

Phytoestrogens are herbal polyphenolic compounds that exert various estrogen-like effects in animals and can be taken in easily from a foodstuff in daily life. The fallopian tube lumen, where transportation of the oocyte occurs, is lined with secretory cells and multi-ciliated epithelial cells. Recently, we showed that estrogen induces multi-ciliogenesis in the porcine fallopian tube epithelial cells (FTECs) through the activation of the estrogen receptor beta (ERβ) pathway and simultaneous inhibition of the Notch pathway. Thus, ingested phytoestrogens may induce FTEC ciliogenesis and thereby affect the fecundity. To address this issue, we added isoflavones (genistein, daidzein, or glycitin) and coumestan (coumestrol) to primary culture FTECs under air–liquid interface conditions and assessed the effects of each compound. All phytoestrogens except glycitin induced multi-ciliated cell differentiation, which followed Notch signal downregulation. On the contrary, the differentiation of secretory cells decreased slightly. Furthermore, genistein and daidzein had a slight effect on the proportion of proliferating cells exhibited by Ki67 expression. Ciliated-cell differentiation is inhibited by the ERβ antagonist, PHTPP. Thus, this study suggests that phytoestrogens can improve the fallopian tube epithelial sheet homeostasis by facilitating the genesis of multi-ciliated cells and this effect depends on the ERβ-mediated pathway.

scholarly journals CHANGES IN FINE STRUCTURE DURING SILK PROTEIN PRODUCTION IN THE AMPULLATE GLAND OF THE SPIDER ARANEUS SERICATUS

1969 ◽  
Vol 42 (1) ◽  
pp. 284-295 ◽  
Author(s):  
Allen L. Bell ◽  
David B. Peakall
Keyword(s):  
Fine Structure ◽  
Epithelial Cells ◽  
Protein Production ◽  
Distal Portion ◽  
Silk Gland ◽  
The Body ◽  
Single Type ◽  
Secretory Cells ◽  
The Web ◽  
Tunica Intima

The ampullate silk gland of the spider, Araneus sericatus, produces the silk fiber for the scaffolding of the web. The fine structure of the various parts of the gland is described. The distal portion of the duct consist of a tube of epithelial cells which appear to secrete a substance which forms the tunica intima of the duct wall. At the proximal end of the duct there is a region of secretory cells. The epithelium of the sac portion contains five morphologically distinct types of granules. The bulk of the synthesis of silk occurs in the tail of the gland, and in this region only a single type of secretory droplet is seen in the epithelium. Protein synthesis can be stimulated by the injection of 1 mg/kg acetylcholine into the body fluids. 10 min after injection, much of the protein stored in the cytoplasm of the epithelial cells has been secreted into the lumen. 20 min after stimulation, the ergastoplasmic sacs form large whorls in the cytoplasm. Protein, similar in electron-opacity to protein found in the lumen, begins to form in that portion of the cytoplasm which is enclosed by the whorls. The limiting membrane of these droplets is formed by ergastoplasmic membranes which lose their ribosomes. No Golgi material has been found in these cells. Protein appears to be manufactured in the cytoplasm of the tail cells in a form which is ready for secretion.

scholarly journals Fine structure of the retinal pigment epithelium and cones of Antarctic fish Notohenia coriiceps Richardson in light and dark-conditions

2007 ◽  
Vol 24 (1) ◽  
pp. 33-40 ◽  
Author(s):  
Lucélia Donatti ◽  
Edith Fanta
Keyword(s):  
Epithelial Cells ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Antarctic Fish ◽  
Basal Region ◽  
Dense Cytoplasm ◽  
Transmission Electron ◽  
Notothenia Coriiceps ◽  
The Antarctic ◽  
Pigment Epithelial Cells

The Antarctic fish Notothenia coriiceps Richardson, 1844 lives in an environment of daily and annual photic variation and retina cells have to adjust morphologically to environmental luminosity. After seven day dark or seven day light acclimation of two groups of fish, retinas were extracted and processed for light and transmission electron microscopy. In seven day dark adapted, retina pigment epithelium melanin granules were aggregated at the basal region of cells, and macrophages were seen adjacent to the apical microvilli, between the photoreceptors. In seven day light adapted epithelium, melanin granules were inside the apical microvilli of epithelial cells and macrophages were absent. The supranuclear region of cones adapted to seven day light had less electron dense cytoplasm, and an endoplasmic reticulum with broad tubules. The mitochondria in the internal segment of cones adapted to seven day light were larger, and less electron dense. The differences in the morphology of cones and pigment epithelial cells indicate that N. coriiceps has retinal structural adjustments presumably optimizing vision in different light conditions.

Nerve Interactions in Salivary Glands

1987 ◽  
Vol 66 (2) ◽  
pp. 509-517 ◽  
Author(s):  
N. Emmelin
Keyword(s):  
Epithelial Cells ◽  
Fluid Secretion ◽  
Salivary Flow ◽  
Regulatory Function ◽  
Secretory Cells ◽  
Amylase Secretion ◽  
Effector Cells ◽  
Release Of Acetylcholine ◽  
Motor Nerves

In the salivary reflex, not only secretory cells are activated, but also myo-epithelial cells are contracted to support these cells and promote the flow of saliva, and blood vessels dilate to meet the increased demands of the tissues. The various effector cells often receive nerves from both parts of the autonomic system, and interactions may occur when the nerves act on the same type of effector, or on different types of effectors. While in an experiment electrical stimulation of the sympathetic trunk may decrease a parasympathetic salivary flow by causing marked vasoconstriction, this does not occur in the salivary reflex, since the vasoconstrictors do not take part. On the contrary, the normal sympathetic vasoconstrictor tone of the resting gland is easily overcome by activity in parasympathetic vasodilator nerves when secretion starts. Pronounced synergism can be demonstrated between sympathetic and parasympathetic secretory nerves. In dogs, for instance, in which sympathetic secretion is β-adrenoceptor-mediated, this is marked in the case of fluid secretion. In rats and rabbits, in which β-receptors elicit secretion of amylase, the potentiating interaction among the nerves is striking when amylase secretion is considered. Even the random release of acetylcholine from the post-ganglionic parasympathetic axons, by itself insufficient to evoke secretion, can increase the sympathetic effects. Motor nerves interact with secretory nerves by causing myo-epithelial contraction, mechanically promoting secretion. Interactions between the nerves in their long-term regulatory function on the sensitivity of the acinar secretory and myo-epithelial cells can also be demonstrated.

scholarly journals Ultrastructure of the Epithelial Cells and Oleogumresin Secretion in Boswellia Serrata (Burseraceae)

IAWA Journal ◽  
1998 ◽  
Vol 19 (4) ◽  
pp. 415-427 ◽  
Author(s):  
M.N.B. Nair ◽  
S.V. Subrahmanyam
Keyword(s):  
Epithelial Cells ◽  
Multivesicular Bodies ◽  
Lipid Bodies ◽  
Secondary Phloem ◽  
Boswellia Serrata ◽  
Tangential Wall

The ultrastructure of epithelial cells of oleo-gumresin ducts in Boswellia serrata, the source of Indian olibanum, is described. Oleo-gumresin ducts are present in primary and secondary phloem. The duct lumen forms an enlarged apoplastic space surrounded by epithelial cells. The epithelial cells are rich in dictyosomes, lipid bodies, mitochondria with dilated cristae, multivesicular bodies, osmiophilic materials, plastids and vesicIes. Plastids have poorly developed internal membranes. Dictyosomes and plastids are possible sites of resin synthesis. The gum component of the exudate is formed in dictyosomes and from the outer layers of the inner tangential wall (wall facing the duct lumen). This wall is replenished from inside by the activity of dictyosomes. The secretory materials are transported to the apoplast by granulocrine and eccrine secretion. They migrate through the loose microfibrils of the inner tangential wall into the duct lumen. Rarely, epithelial cells of young ducts have rudimentary plasmodesmata on the inner tangential wall which may be channels for passage of secretory materials into the duct lumen.

A New Species of Eriosema (Leguminosae, Papilionoideae, Phaseoleae) from Mato Grosso do Sul, Brazil, with a Secretory Structure Novel to the Genus

Phytotaxa ◽  
2016 ◽  
Vol 263 (2) ◽  
pp. 122 ◽  
Author(s):  
ELISA SILVA CÂNDIDO ◽  
WANDERLEIA DE VARGAS ◽  
MOHAMMAD VATANPARAST ◽  
VIDAL DE FREITAS MANSANO ◽  
SILVIA RODRIGUES MACHADO ◽  
...  
Keyword(s):  
New Species ◽  
Identification Key ◽  
Secretory Cells ◽  
Secretory Structures ◽  
Mato Grosso ◽  
Inflorescence Axis ◽  
First Time ◽  
Mato Grosso Do Sul ◽  
A New Species

Eriosema grearii, a new species for the genus (Leguminosae, Papilionoideae, Phaseoleae, Cajaninae), is described and illustrated. Similar to E. heterophyllum, it differs from it morphologically by the free (vs. joined) stipules, lax flowers distributed along the inflorescence axis (vs. congested and concentrated at its apex), inflorescences not opposite to the leaves (vs. opposite), and leaflets with secretory cells at the base of trichomes (vs. absence of secretory cells at the base of trichomes). A survey of the leaflet secretory structures revealed that E. grearii has distinct secretory structures, referred here as secretory-base trichomes, and reported for the first time for the Phaseoleae tribe. An identification key for the Eriosema species in Mato Grosso do Sul, where the new species occurs, is provided.

scholarly journals Bacillus pumilus, a Novel Ginger Rhizome Rot Pathogen in China

Plant Disease ◽  
2013 ◽  
Vol 97 (10) ◽  
pp. 1308-1315 ◽  
Author(s):  
Qin Peng ◽  
Yihui Yuan ◽  
Meiying Gao
Keyword(s):  
Molecular Biology ◽  
Bacillus Pumilus ◽  
Shandong Province ◽  
Gram Positive ◽  
Disease Symptoms ◽  
Starch Grains ◽  
First Report ◽  
Ginger Rhizome ◽  
Parenchyma Cells ◽  
Rhizome Rot

Ginger rhizome rot is a major factor limiting the yield and marketability of ginger in Shandong Province, China. In order to identify the pathogen causing ginger rhizome rot, evaluate its pathogenicity, and explore its pathogenesis, diseased ginger rhizomes and surrounding soils were collected. A gram-positive, spore-forming, rod-shaped bacterium, designated GR8, was frequently isolated from the ginger rhizome samples. The bacterium was identified as Bacillus pumilus based on physio-biochemical and molecular biology characteristics. Pathogenicity studies with GR8 showed that it could cause disease of the tested rhizomes slices and the entire rhizome when wounded but no disease occurred when the rhizome was not wounded. Preliminary pathogenicity studies demonstrated that cell-free cultures of GR8 could not cause any disease symptoms, whereas the bacterial suspensions caused severe symptoms. The pathology studies revealed that infection of GR8 could cause starch grains to shrink from normal size, and destroy the parenchyma cells by invading and propagating in them. This is the first report of B. pumilus causing ginger rhizome rot.

Cortisol, parathyroid hormone-related protein and the onset of calcium secretion by the mammary gland of the goat

1997 ◽  
Vol 64 (4) ◽  
pp. 633-636
Author(s):  
GORDON E. THOMPSON ◽  
S. KHAWAR ABBAS ◽  
CARL HOLT ◽  
ANTHONY D. CARE
Keyword(s):  
Mammary Gland ◽  
Parathyroid Hormone ◽  
Epithelial Cells ◽  
Tight Junctions ◽  
Calcium Transport ◽  
Extracellular Fluid ◽  
Secretory Cells ◽  
Related Protein ◽  
Parathyroid Hormone Related Protein ◽  
Calcium Secretion

During lactogenesis in the goat, the onset of secretion of calcium into milk occurs at parturition (Thompson et al. 1995) at approximately the same time as the onset of secretion of parathyroid hormone-related protein (PTHrP) by the mammary gland (Ratcliffe et al. 1992); these events may be unrelated or PTHrP may be involved in calcium transport from blood to milk.Parturition in goats is initiated by fetal secretion of cortisol (Flint et al. 1978) and maternal secretion of cortisol also increases (Paterson & Linzell, 1971). Injecting cortisol locally into the sinus of a mammary gland of the late-pregnant goat when the tight junctions between secretory epithelial cells appear to be ‘loose’, and injectate can reach the basolateral surfaces of secretory cells, stimulates an early tightening of these junctions (Thompson, 1996) as occurs naturally at parturition. This tightening can be produced by an increased concentration of ionized calcium in the extracellular fluid of the gland (Neville & Peaker, 1981).The experiments reported here were undertaken to determine if cortisol injection stimulates the mammary gland to secrete both PTHrP and calcium before parturition.

scholarly journals Histochemical structure and immunolocalisation of the hyaluronan system in the dromedary oviduct

2016 ◽  
Vol 28 (7) ◽  
pp. 936 ◽  
Author(s):  
Omnia Mohey-Elsaeed ◽  
Waleed F. A. Marei ◽  
Ali A. Fouladi-Nashta ◽  
Abdel-Aleem A. El-Saba
Keyword(s):  
Epithelial Cells ◽  
Molecular Size ◽  
Blue Staining ◽  
Secretory Cells ◽  
Alcian Blue Staining ◽  
Basal Region ◽  
Epithelial Surface ◽  
Ciliated Epithelial Cells ◽  
Oviductal Fluid ◽  
Local Modulation

We investigated the local modulation of some histochemical properties of oviducts of the dromedary (Camelus dromedarius), focusing on the immnolocalisation of hyaluronic acid (HA) synthases (HAS2 and HAS3), hyaluronidases (HYAL2 and HYAL1) and the HA receptor CD44 in the ampulla and isthmus. Abundant acidic mucopolysaccharides (glycosaminoglycans) were detected by Alcian blue staining along the luminal surface of both ciliated and non-ciliated epithelial cells (LE). Staining for HAS2 was higher in the primary epithelial folds of the ampulla compared with the isthmus, especially in secretory cells, adluminal epithelial surface and supranuclear cell domain. HAS3 staining was stronger in the LE of the isthmus than ampulla. HYAL2 was detected in the LE in the ampulla and isthmus and was more intense in the adluminal projections of secretory cells. HYAL1 was weakly detected in the LE with no difference between the ampulla and isthmus. Strong CD44 immunostaining was present in the LE of the ampulla and isthmus. CD44 staining was higher in secretory cells than in ciliated epithelial cells and was higher in the supranuclear region than the basal region of the cytoplasm. In conclusion, we provide evidence that HA synthesis and turnover occur in the camel oviduct. Differences in HAS2 and HAS3 expression suggest regional differences in the molecular size of HA secreted in oviductal fluid that may influence oviduct–gamete interaction in the camel.

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