• International Journal of Industrial Entomology and Biomaterials
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• v.29 no.1
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• pp.120-127
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• 2014

The cerebral neurosecretory cells (NSC) constitute four paired groups, medial (MNC), lateral (LNC-I, LNC-II) and posterior (PNC) in the brain of larvae of tasar silkworm Antheraea mylitta (D) Eco-race Bhandara. The MNC is the largest groups of peptidergic neurosecretory cells and are located in the pars intercerebralis region. The transmission electron microscopic (TEM), ultrastructure of the NSC confirmed the presence of mitochondria, endoplasmic reticulum, Golgi bodies, lysosomes and neurosecretory granules. The median neurosecretory cells shows secretory activity and release of secretory products, the neurosecretory granules (NSG) in the axons of NSC as well as the blood sinus.

• Journal of Sericultural and Entomological Science
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• v.16 no.2
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• pp.111-117
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• 1974

The electron micrographs of the larval brain of the silkworm. Bembyx mori. show that median neurosecretory cell of diapause-egg producer may participate in the production of lipo-granules and that of non-diapause egg producer may do in the production of electron-translucent vesicles. It was found that ribosome-like particles of diapause-egg producer gradually developed into highly dense particles and came into line along the smooth-surfaced endoplasmic reticulum. They finally became lipo-granules.

• Applied Microscopy
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• v.12 no.2
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• pp.55-68
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• 1982

The study on the nerve cells in the pars intercerebralis(IP) of 5-day-old cabbage butterfly Pieris rapae L. was performed to observe their ultrastructures and classify them on the basis. of the differences in size, shape and relative distribution cf cell organelles. The brain-subesophageal ganglion complex was fixed in 1% paraformaldehyde-1% gluaraldehyde mixture and embedded in araldite mixture. The transverse thin sections of IP were stained with uranyl acetate and lead citrate and examined by Hitachi 500 and ]EM 100B electron microscope. Five distinct types. of nerve cells are recognized and are arbitrarily designated as Type I, Type II Type III, Type IV and Type V. Type I neurone: These neurones are neurosecretory cells. Several neurosecretory cells are. recognized in the pars intercerebralis. They are roughly round or peach-shaped cells measuring $13{\sim}25{\mu}m$ in diameter. The rounded nucleus shows about $5{\sim}10{\mu}m$ in diameter. The chromatin is predominantly diffused with only occasional dense patches. The perikaryon contains numerous. mitochondria, free polyribosomes and neurosecretory granules. The neurosecretory granules are relatively uniform in electron density, and each one is about $100{\sim}400{\mu}m$ in diameter and surrounded by a single membrane. The granules are also observed mostly as in groups. In one group of neurones the cisternae of endoplasmic reticulum are distended or in other group of neurones are not distended. Golgi saccules are slightly dilated at their lateral extremities and contains. frequenty dense rounded materials. Type II neurone: Thes have the largest soma in the pars intercerebralis about $30{\sim}35{\mu}m$ in diameter. They also show roughly polygonal in shape. The nucleus is elongated or sickle-shaped. The chromatin is mainly in the euchromatin form. The perikarya in these cells are well populated with populated with free ribosomes and contain numerous mitochondria and Golgi bodies. The cisternae of granular endoplasmic reticulum are also well distributed. Type III neurone: They are oval or spindle-shaped and also medium-sized. neurones approximately $15{\sim}17{\mu}m$ in length. The nucleus is oval or slightly elongated in shape and $8{\sim}9{\mu}m$ in length. The chromatin occurs in diffused form. The cytoplasm contains many filamentous or oval mitochondria. The perikaryon has also numerous free polyribosomes and cisternae of granular endoplasmic reticulum. Type VI neurone: They are roughly polygonal in shape probably due to the close approximation of the adjacent cells. The soma is about $7{\sim}8{\mu}m$ in diameter. The nucleus is round or oval in shape and $5.0{\sim}5.8{\mu}m$ in diameter. The necleus also occupies a large proprion of the cell body. The perikaryon is well populated with free ribosomes and contains several mitochondria and cistenae of granular endoplasmic reticulum. Type V neurone: These neurones are similar to Type VI neurones in various respects such as cell size and cell inclusion, but they differ from Type IV neurones in shape. The soma is oval or slightly elongated. The cell body contains several filamentous and oval mitochondria.

• Applied Microscopy
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• v.31 no.1
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• pp.101-108
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• 2001

Five kinds of neurosecretory cells (type-A, B, C, D and E) and neuropiles surrounding them were observed in the visceral ganglion and the right parietal ganglion of the African giant snail, Achatina fulica, by transmission electron microscopy. Type-A cells (diameter, $35{\mu}m$) are the most popular cells in the cortex of the two ganglions, which are of triangular or irregular forms. In their cytoplasm, there are found large granules of 1 fm in diameters and small round granules of about $0.1{\mu}m$ in diameters. Small granules are classified into the ones of high electron density and the others of middle electron density. Type-B cells (diameter, $19\times12{\mu}m$) are evenly distributed over various portions of cortex and medulla of the two ganglions. They are similar to type-A cells in shapes. The cytoplasm of type-B cells is crowded with high electron dense granules of about $0.1{\mu}m$. Round granules of about $0.7{\mu}m$ in diameters are also found but rarely. Type-C cells are the smallest cells whose sizes are about $8\times6{\mu}m$. Each of them contains a large nucleus of about $6\times5{\mu}m$. Its cytoplasm is full of electron dense granules of about $0.23{\mu}m$, each of which is artually an assembly of tiny granules of about $0.03{\mu}m$. Type-D cells are middle-size cells of about $28\times20{\mu}m$, which take ellipsoidal or irregular forms. They are found in the cortex more than in the medulla. Their cytoplasm looks dark due to the high electron density and, in it, two kinds of round granules whose sizes are $1.6{\mu}m$fm and $0.6{\mu}m$, respectively, are observed. Type-E cells are large cells of about $100\times50{\mu}m$, which are rarely found in the upper and middle portions of the two ganglions. The nucleus of the cell, which is very large $(70\times30{\mu}m)$ for the cytoplasm, contains electron dense round granules of diverse sizes (diameters, $1\sim0.2{\mu}m$). The surface of the cell protrudes filopodia of various forms and phagocytizes decrepit cells. Neuropiles are surrounding the neurosecretory cells. In nerve fibers, synaptic vesicles are observed, which are classified into six classes according to their electron densities , sizes and shapes.

• Applied Microscopy
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• v.29 no.1
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• pp.57-66
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• 1999

The nervous tissue in the cerebral ganglion of Korean planaria was observed using electron microscope. The obtained results are as follows: A cerebral ganglion is composed of the nerve cells, neurosecretory cells, neuroglial cells and neuropils. The nerve cells are round or ovoidal-shaped cells (diameter, $5{\mu}m$), which has a large ellipsoidal nucleus containing the evenly developed heterochromatin. Their cytoplasms were found to be relatively simple, because of their undeveloped cell organelles. The neurosecretory cells are long and ellipsoid or spindle-shaped cells, where there were found a large ellipsoidal nucleus and cytoplasm filled with secretory granules (diameter, 60 nm). The neuroglial cells were seldom observed. They are spindle-shaped cells (size, $6\times0.8{\mu}m$), which were observed mainly among the nerve fibers. The neuropils are formed by the nerve fibers and nerve endings which are filled with mitochondria, neurotubules and secretory granules of four kinds (high electron dense granules of sizes 75 nm, 50 nm and 37 nm, and electron lucent granule of size 30 nm etc.). These granular vesicles are divided into single vesicle type and compound vesicle type in the nerve terminals, and neuronal synapses were observed to be the axo-dendritic and dendro-dendritic synapse type.

• Journal of Chest Surgery
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• v.19 no.3
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• pp.433-437
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• 1986

Authors experienced a case of typical carcinoid in a patient of 46 year-old female who has been suffered from hemoptysis intermittently for 13 years. Exploratory thoracotomy and middle and lower lobectomy was carried out. The tumor was located in the right intermediate bronchus. Tissue pathology shows a glandular tumor with focal proliferation of Kulchitzky cells in the bronchial epithelium by H&E stain and membrane-bounded neurosecretory granules in the cytoplasm by electron microscope. Authors report the case with a literature reviews.

• Applied Microscopy
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• v.11 no.1
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• pp.1-9
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• 1981

The study on the nerve cells in the subesophageal ganglion of 5-day-old cabbage butterfly, Pieris rapae L., was performed to observe their ultrastructures and classify them on the basis of the differences in size, shape and relative distribution of cell organelles. 1. Type I neurons: These cells are neurosecretory granules ranging 100 to 300 nm in size. 2. Type II neurons: As giant neurons averaging 25 to $30{\mu}m$ in size, such as mitochondria and Golgi apparatus. 3. Type III neurons: These spindle-shaped cells range 9 to $15{\mu}m$ in width. 4. Type IV neurons: These cells have a range of diameter from 12 to $16 {\mu}m$. The cells are abundantly observed in the subesophageal ganglion. 5. Type V neurons: These cells are very small nerve cells with 4.5 to $8.0{\mu}m$ in size and have a prominent nucleus.

• Applied Microscopy
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• v.29 no.3
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• pp.303-313
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• 1999

In this paper, five kinds of neurosecretory cells-light green (LG) cell, dark green (DG) cell, caudo-dorsal (CD) cell, blue green (BG) cell, and yellow (Y) cell- and neuropils in the cerebral ganglion of the African giant snail, Achatina fulica, were observed with an electron microscope. The following results were obtained. The LG cells are circular or ovoid in shape, and about $60{\mu}m$ in size. The nucleus and cytoplasm of the LG cell look light due to their electron-low density. Large granular chromatins are evenly developed in the karyolymph, where round nucleoli are also found. In the cytoplasm, electron -high dense round granules of $0.4{\mu}m$ in average size are crowded. The DG cells are ovoid in shape, and $50\sim20{\mu}m$ in size. These relatively electron-high dense cells were rarely found. In their cytoplasm, cell organelles such as rough endoplasmic reticulum and mitochondria are found together with electron -high dense round granules of $0.2{\mu}m$ in average size. The CD cells are ellipsoidal cells densely distributed in caudo-dorsal parts of the cerebral ganglion. They have large nuclei compared with the cytoplasm. The developed granular heterochromatins are observed in the karyolymph, and lots of small round granules of $0.12{\mu}m$ in average size in the cytoplasm. The 3G cells, rarely found around endoneurium of the cerebral ganglion, take the shapes of long ellipses. They look dark due to their electron -high density. In the cytoplasm, small round granules of $0.1{\mu}m$ in average size are found. The Y cells are the smallest among the neurosecretory cells($9\times6.6{\mu}m$ in size). They are found mostly between the medio-dorsal parts and the caudo-dorsal parts of the cerebral ganglion. In the cytoplasm, tiny round granules of $0.08{\mu}m$ in average size form a group. The neuropils are found in the middle of the cerebral ganglion. In the axon ending, round granules with electron -high density ($0.07\sim0.03{\mu}m$ in diameter) and lucent vesicles ($0.03{\mu}m$ in diameter) are found in large quantities. They are excreted in the state of exocytosome formed by the invagination of the limiting membrane of the axon ending.

• The Korean Journal of Zoology
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• v.16 no.1
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• pp.25-41
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• 1973

Ultrastructural changes in the cells of the corpora allata of the pine moth, Dendrolimus spectabilis Butler, were studied by electron microscope to know the structural correlates of hormone production by the gland during the larval-pupal-adult transformations. Mitochondria are in active phases from the overwintered to the last instar larvae and from the pupae just after pupation to the 20-day old pupae, while they are in inactive phases from the making cocoon stage to the prepupae just before pupation. The peripheral allatum cells have electron dense granules in the intracellular vacuoles of smooth-surfaced endoplasmic reticulum in the larval life, particularly in the overwintered larvae and in the early adults but the swollen smooth-surfaced intracytoplasmic vacuoles made by expansion of an end of the tubular rough endoplasmic reticulum, some of which contain fibrous proteins, are observed in addition to the vacuoles in the intercellular spaces in which the vacuoles grow by fusing each other from the mature larvae to the prepupae, both of them disappearing during just before pupation. After pupation the cytolasmic vacuoles develop again in the allatum cells so that they seem to begin the secretory activity. The fact that the neurosecretory granules stored within the axons terminated in the corpus allatum are visible only from the 20-day old pupa about two days before abult emergence to the 5-day old adult means that the secretion from the allatum cells is under the control of the brain from the late pupal stage, while the secretion during from the larval to the early pupal life has no relation with the brain, because such granules are not observed within the axons. It is, therefore, suggested that at least two kinds of hormone are released with the ages as far as concerned with the production and secretion mechanisms of the allatum hormone: juvenile hormone is released until the last instar larvae without any direct stimlation of the brain and gonadotropic hormone is secreted from the late pupa to the adult by getting brain's stimulation and that the secretory phases observed from the mature larvae to prepupae are presumably concerned with the biosynthesis of protein owing to the ecdysone and those from the early pupal stage in uncontrolled condition of the brain with the prothoracotropic activity.