• Korean Journal of Veterinary Pathology
• /
• v.3 no.1
• /
• pp.35-44
• /
• 1999

The morphologic changes of small intestinal epithelium in pigs diagnosed as porcine epidemic diarrhea(PED} by virus isolation and immunohistochemistry were studied through light microscope and transmissible electron microscope. On semi-thin section, the histologic findings showed severe villous atrophy and fusion with hyperplasia of cuboidal epithelium in the villi, inflammatory cell infiltration in lamina propria, and increased mitotic figures in the crypt. The structural changes were mostly restricted to the cytoplasm of affected absorptive epithelium of villi. 3 types of epithelial changes were found; degenerated virus-affected cells, undifferentiated cuboidal cells, and normal columnar cells. On electron microscopy, round to spherical viral particles of 50∼l00nm in diameter were found within the dilated vesicles and endoplasmic reticulums of degenerated cells, which had decreased their cytoplasmic electron density due to dilated and missing organelles(e.g. mitochondria, ERs, etc.). Microvilli were shortened and sparse, leaving denuded terminal web of the villous epithelial cells. Fat globules were often found within slightly degenerated enterocytes. On the tip of villi, severely damaged cells were exfoliated and replaced by undifferentiated cuboidal cells We found distinct ultrastructural changes in the jejunal epithelium confirming PED virus infection is involved in malabsorptive diarrhea.

• Journal of Korean Neurosurgical Society
• /
• v.44 no.3
• /
• pp.124-130
• /
• 2008

Objective : Our purpose of this study is to compare insertion angles and screw lengths from Roy-Camille, Magerl, and our designed method for cervical lateral mass screw fixation in the Korean population by quantitative measurement of reformatted two dimensional (2D) computed tomography (CT) images. Methods : We selected thirty Korean patients who were evaluated with thin section CT scans and reconstruction program to obtain reformatted 2D-CT images of the transversal plane passing the cranio-caudal angle using three different techniques. We measured the minimum angle to avoid vertebral artery (VA) injury, the ideal angle and depth for bicortical screwing of cervical lateral mass. Morphometric measurements of the lateral masses from C3-C7 were also taken. Results : In all three techniques, the mean safety angles from the VA were less than 8 degrees and the necessary depth of the screw was about 14 mm for safety to the VA and for the bicortical purchase. In our designed technique, the mean $\beta$ angles of each level from C3 to C7 were 29.0. 29.8. 29.5. 26.3. and 23.9 degrees, respectively. Conclusion : Results of this study and data from the literature indicate that differences may exist between the Korean and Western people in the length and angle for ideal lateral mass screw fixation. In addition, our technique needs further cadaveric and clinical study for safety and efficacy for being performed as alternative method for cervical lateral mass fixation.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.8 no.1
• /
• pp.99-103
• /
• 1970

This study aimed to contribute fundamental study of sprouting in Gibberellin treated potatoes, and studied about Glucose and Sucrose amount and its sprouting stem structure in it sprouting seed potatoes with Gibberellin treatment. The results obtained are as follow; The quantity of glucose in gibberellin treated seed potatoes showed remarkable increase in comparison with that of those untreated, and the increment went up as the seeding date pass. As to the concentration of gibberellin, the 10 ppm plot contained more glucose than 5 ppm plot but 14th after seeding, it was found that this tendency was reversed. The increasing tendency of the quantity of sucrose in gibberellin treated seed potatoes were similar to that of glucose. The sprouting stems of the gibberellin 10 ppm and 5ppm plot were all longer than the controls. And after 14 days on account of thin ing growth by gibberellin treatment, the sprouting stems of the 5ppm plot were longer than 10ppm plot. The microscopic vertical and cross section of the gibberellin treated sprouting stems showed larger cells than those of untreated. The cells of sprouting stem treated by gibberellin 10 ppm were larger than those of the stems treated 5ppm.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 1998.11a
• /
• pp.89-94
• /
• 1998

Marine sponges are recognized as a plentiful source of diverse biologically active secondary metabolites. Recently, we have initiated a research to discover antitumor constituents from the marine sponges collected from Korean Waters. Marine sponges collected from the South Sea of Korea were screened for several biological activities including such as brine shrimp lethality and cytotoxicity. Significant brine shrimp lethality was detected in the crude extract of a two-sponge association of Poecillastra sp. and Jaspis sp. A cross-section of this sample showed two layers of morphologically distinct sponges. The thin and dirty yellow outer layer was identified as Poecillastra sp. (Pachastrellidae), the surface of which was very rough. The light-grey inner layer was identified as Jaspis sp. (Jaspidae), the surface of which was smooth. This two-sponge association appears to be consistent as these sponges were always found in associated form regardless of collection site or collection period. Investigation of the bioactive constituents monitored by brine shrimp lethality assay led to the isolation of pectenotoxin II (PTX2) and psammaplin A as causative compounds for the brine shrimp lethality. $^1$H- and $\^$13/C-nmr signals of PTX2 was fully assigned utilizing TOCSY, HETCOR, Long-range HETCOR, and Homonuclear J-resolved 2D experiments. PTX2 displayed very potent and selective cytotoxicities in the 60 cell line panel antitumor assay at the NCI. PTX2 has progressed to acute toxicity determination and in vivo antitumor assay at the NCI (Table 1). However, significant in vitro antitumor activity of PTX2 can not be affirmed in the in vivo assay.

• Korean Journal of Veterinary Research
• /
• v.40 no.4
• /
• pp.665-670
• /
• 2000

The present study was undertaken to investigate the morphological characteristics of the suprachiasmatic nucleus (SCN) of the Korean native goat by cresyl violet stain. The SCN was located ventrolateral to the third ventricle and dorsal to the optic chiasm. This nucleus was showed carrot form in longitudinal section. Its size was 1.8 mm in length, 0.9 mm in maximum height and 1.6 mm in maximum width. In coronal sections, the SCN shaped very thin plate in rostral part, but it was changed to sweet-potato form in middle part, and ornamental jade form in caudal part. The size of SCN was larger in caudal part than in rostral part. The size of the neuron of SCN was about $10{\mu}m$ in diameter with round or oval shape. The boundary of SCN was not firmly defined in caudal part because the neurons were dispersed into the hypothalamic region. It is concluded that the SCN of the Korean native goat has a morphological characteristics.

• Applied Microscopy
• /
• v.15 no.1
• /
• pp.71-85
• /
• 1985

The ultrastructure on the dorsal vessel of 5-day-old cabbage butterfly, Pieris rapae L., was carried out using the transmission and scanning electron microscope. The results are as follows. 1) The aorta. The aorta is simple tubular type and consists of the inner and outer membrane of the myocardium and thick myocardium is located between them. However the inner membrane with $0.26{\mu}m$ thickness and outer membrane with $0.08{\mu}m$ are composed of fibrous materials, the former is composed of low and high densed fibrous materials and the latter appears homogeneous layer. The myocardium consists of typical striated muscles. The sarcomere with $1.6{\mu}m$ length and in cross section, each thick filaments are surrounded by $7{\sim}8$ thin filaments. The intercalated disc is joining the end of the two muscle cells, desmosomes and septate junctions are appeared between the neighboring muscle cells. 2) The heart. The heart composing of myocardium enclosed by its inner and outer membrane as the aorta has a series of well formed segmental chamber. The arrangement of myofilaments, cell adhensions and membrane elements are observed as same as at the aorta. The inner membrane of the heart is deeply invaginated into the myocardium than the outer membrane and a lot of well developed mitochondria with rod shape are aggregated in the folds. The longitudinally and transversely oriented tubule system formed by invagnation of the sarcolemma into the muscle bundle is built up dyad with the sarcoplasmic reticulum as the aorta. The slit is formed by deeply invagination of the inner membrane of myocadium toward the muscle layer and then the inner and outer membrane of myocardium are fused. Therefore, the ostium is formed between the myocardium and situated at the lateral side of the myocardium.

• Applied Microscopy
• /
• v.41 no.1
• /
• pp.69-73
• /
• 2011

High-voltage electron microscope (HVEM) has higher resolution and penetration power than conventional transmission electron microscope that could be load thick specimen. Some researchers have taken this advantage of HVEM to explore 3-dimensional configuration of the biological structures including tissue and cells. Whole mount preparations has been employed to study some cell lines and primary culture cells. In this study, we would like to introduce useful whole mount preparation method for neuronal studies. The plastic coverslips were punched, covered by formvar membrane and coated with carbon. The neurons obtained embryonic 18 rat hippocampus were seeded on the prepared cover slip. The coverslips were fixed, dried in freeze drier and kept in a descicator until HVEM observation. We could observe detailed neuronal structures such as soma, dendrite and spine under HVEM without conventional thin section and heavy metal stain. The anaglyphic image based on stereo paired image ($-8^{\circ},+8^{\circ}$) provides three dimensional perception of the neuronal dendrites and their spines. This method could be applied to sophisticated analysis of dendritic spine under the various experimental conditions.

• Tuberculosis and Respiratory Diseases
• /
• v.55 no.5
• /
• pp.526-530
• /
• 2003

Bronchogenic cysts are generally presented as a well defined mass that have thin and smooth wall in the intrapulmonary or mediastinal area by simple chest radiographs. We present the case of a 20-year-old man with a ill-defined left upper lobe mass, found by chest radiographs. At the preoperative examinations, chest computed tomography showed ill-defined mass with Hounsfield Number 26, and nonspecific findings were shown by the bronchoscopy and percutaneous needle aspiration. The patient was undertaken the left upper lobectomy. The surgical specimen contained a ill-defined mass, measuring $2{\times}3$ cm. On the section of the mass, a cyst containing dark brown thick materials was noted. The cyst was unilocular, and the wall showed a trabeculation. Microscopically, the cystic mass was lined with ciliated pseudostratified columnar epitheliums and surrounded by smooth muscle and cartilage.

• Korean Journal of Ichthyology
• /
• v.32 no.3
• /
• pp.136-142
• /
• 2020

Morphology and osteology of the slender ribbonfish, Trachipterus ishikawae was described and figured in detail. The morphological characteristics are as follow: body elongate and compressed; upper jaw protrusile; tubercles along ventral edge of body and tail; eyes are large; body naked; caudal fin long and at a right angle to the body; from (3~4)+(7~8) gill rakers; from 180 to 185 dorsal fin rays, from 12 to 13 pectoral fin rays; 9 caudal fin rays and 5+2 short spine at caudal spine. The osteological characteristics are as follow: premaxillary is long and has four teeth; dentary is triangle shape; interopercle and subopercle are wide and flat; 5 branchiostegal rays; post clavicle is thin and long; from 79 to 80 centrum; posterior vertebrae elongate; 5~6 tubercles at urostyle bone.

• Steel and Composite Structures
• /
• v.1 no.1
• /
• pp.17-32
• /
• 2001

The Rosette-joining system is a completely new press-joining method for cold-formed steel structures. One Rosette-joint has a shear capacity equal to that of approximately four screws or rivets. The Rosette thin-walled steel truss system presents a new fully integrated prefabricated alternative to light-weight roof truss structures. The trusses are built up on special industrial production lines from modified top hat sections used as top and bottom chords and channel sections used as webs which are joined together with the Rosette press-joining technique to form a completed structure easy to transport and install. A single web section is used when sufficient but can be strengthened by double-nesting two separate sections or by using two lateral profiles where greater compressive axial forces are met. An individual joint in the truss can be strengthened by introducing a hollow bolt into the joint hole. The bolt gives the connection capacity a boost of approximately 20%. A series of laboratory tests have been carried out in order to verify the Rosette truss system in practice. In addition to compression tests on individual sections of different lengths, tests have also been done on small structural assemblies and on actual full-scale trusses of a span of 10 metres. Design calculations have been performed on selected roof truss geometries based on the test results, FE-analysis and on the Eurocode 3 and U.S.(AISI) design codes.