• 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.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.

• The Korean Journal of Zoology
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• v.37 no.1
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• pp.12-18
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• 1994

The prothoracicotropic hormone (PTTH) produced by the neurosecretory cells in insects is involved in molting and metamorphosis by activating the prothoracic frins) glands to secrete ecdysone (or related ecdvsteroidsl. In the present study, the small PTTH-like gene was isolated by screening of CDNA library using the bombvxin (corresponding to small PTTH in Bombvx moril gene probe in Drosophilo melonogaster. It showed 50-6096 sequence homology to bombyxin gene. The expression patterns of this gene showed developmental stage- and tissue-dependent manners. The mRNA was detected only in the late third instar larval-prepupa which is stases showing the highest hormonal activity to secrete ecdysteroids, and detected in the brain pan of the Isle third instar lanrae.

• Animal cells and systems
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• v.5 no.3
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• pp.211-216
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• 2001

Polyclonal antiserum against Manduca sexta allatotropin has been utilized to investigate the localization of allatotropin-immunoreactivity in the brain of the si1k moth Bombyx mori. Manduca sexta allatotropin-immunoreactive (Mas-AT-IR) neurons were found in all larval brains investigated, but not in prepupal, pupal and adult brains. In the larval stages, first appearance of Mas-AT-immunoreactivity w8s shown in the brain of first instar larvae, which contains four pairs of bilateral Mas-AT-IR cell bodies. Labeled neurons increased to six pairs in the second instar larval brain, including two pairs of median neurosecretory cells in the pars intercerebralis. In the third and fourth instar larvae, five pairs of labeled cell bodies were distributed throughout each brain. In the fifth instar, there were about ten pairs of bilateral cell bodies in the day-1 brain, about seven pairs in the day-3 brains, and five pairs in the day-5 brains, respectively. Mas-AT-labeling was observed in both axons within nervi corpora cavdiaci (NCC) 1+11 and corpora allata. This suggests that the Mas-AT produced from the brain neurons is transported via some axons of the NCC 1+11 and nervi corpora allati I to the corpora allata, which appears to be a main accumulation site for the Mas-AT neuropeptide in some brain neurons produced in B. mori.

• 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.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 1997.06a
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• pp.51-72
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• 1997

Diapause hormone (DH) is a neuropeptide hormone which is secreted from the suboesophageal ganglion (SG) and is responsible for induction of embryonic diapause of the silkworm, Bombyx mori. DH is isolated from SGs and determined to be a 24 amino acid peptide amide. The cDNA encodes the polyprotein precursor from which DH, pheromone biosynthesis activating neuropeptide (PBAN) and three other neuropeptides are released and become matured. The C-terminal FXPRL-NH2 sequence of DH is essential but not sufficient for expression of full activity. Recently, we have isolated a unique hydrohobic peptide (VAP peptide) with a slight diapause egg induceing activity from organic solvent extracts of the male adult heads of the silkworm. The VAP peptide itself has no diapause inducing activity, but enhances DH activity through reducing ED50 value and the threshold concentration of DH. The DH-PBAN gene is composed of 6 exons interrupted by 5 introns and is expressed in 12 neurosecretory cells of the SG. The incubation of eggs at 25$^{\circ}C$, which induces embryonic diapause in the progeny, caused DH-PBAN mRNA content to increase at 5 different stages in the life cycle. By contrast, a 15$^{\circ}C$ incubation only induced expression of the gene at the late phrase adult stage. The temperature-controlled expression of DH-PBAN gene is closely correlated to the incidence of diapause, indicating that DH-PBAN gene expression is the initial event leading to diapause induction. DH acts to stimulate trehalase activity in developing ovary to bring about hyprglycogenism in mature eggs, a prerequisite metabolism for diapause initiation. Using in vivo and in vitro systems, DH is clearly shown to induce trehalase gene expression in developing ovaries. New protein synthesis is not needed for this process, but a Ca2+-dependent proteinkinase seems to be involved. Quite recently, we have sucessfully applied a new and potent trehalase inhibitor (Trehazoline) to reudce glycogen content in developing ovaries. The eggs deficient in glycogen were also able to enter diapause as the natural eggs do, so that we could provide the new egg system to reconsider the diapause associated metabolism other than the glycogen-sorbitol metabolic system.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.15-28
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• 2022

Neuropeptides produced in neurosecretory cells are the largest group of insect hormones. They regulate various physiological functions, such as fat body homeostasis, feeding, digestion, excretion, circulation, reproduction, metamorphosis, and behavior throughout all life stages. The PRXamide peptide family (X, a variable amino acid) is a well-characterized neuropeptide component with a common amino acid sequence, PRXamide (NH₂), at the C-terminal end conserved across Insecta. The PRXamide peptides are classified into three subfamilies, each having diverse biological roles in insects: (1) pyrokinin (PK) includes the pheromone biosynthesis activating neuropeptide (PBAN) and the diapause hormone (DH), (2) the capability (CAPA) peptides, and (3) the ecdysis-triggering hormone (ETH). PBAN as a member of PK subfamily was first identified to stimulate pheromone biosynthesis in moths three decades ago. Since then, PBAN peptides have been extensively studied by various research groups from a broad spectrum of arthropods. In this paper, we briefly review insect PBAN molecules with emphasis on gene structure and expression, signal transduction, physiological mechanism in sex pheromone biosynthesis, and application for pest management.

• 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.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.1
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• pp.76-90
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• 1993

To clarify the relations between photoperiodism and x-organ of eyestalks to the control of gonadal maturation in a freshwater prawn, Macrobrachium nipponense, the present investigation was performed with following examinations: 1) the influence of water temperature and daylength on the control of gonadal maturation, 2) the effect of eyestalk ablation on the gonadal maturation, 3) the seasonal variation of histology of MEX-organ (medulla externa X-organ) in the eyestalk. In previtellogenesis period (December${\sim}$March) and vitellogenesis period (April${\sim}$May), gonadal maturation was considerablely influnced by water temperature. In these periods, GSI increased and gonads were matured with water temperature rising without regard to photoperiod conditions (12L/12D and 15L/9D). In spawning period (June${\sim}$August), however, gonadal maturation was influenced by photoperiod condition. While high value of GSI was kept at long photoperiod regime (15L/9D), GSI was decreased at short photoperiod regime (12L/12D). In resting period (September${\sim}$November), no rematuration was occurred at all the experimental regimes combinated with water temperatures ($16^{\circ}C,\;22^{\circ}C,\;28^{\circ}C$) and photoperiod (12L/12D, 15L/9D). Effect of X-organ which inhibite the gonadal maturation was stronger in resting period than that in previtellogenesis and ealy spawning periods by observations on the effectiveness of eyestalk ablation on the gonadal maturation. In MEX-organ of eyestalk, the number of neurosecretory cells of which size was over $20{\mu}m$ in diameter varied according to the reproductive cycle. The number of cells increased $77{\pm}12$ in resting period, and decreased $55{\pm}7$ in vitellogenesis period. Volume of Bellonci's organ, however, increased in vitellogenesis period in comparison with that in resting period.