• Applied Microscopy
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• v.15 no.2
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• pp.31-68
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• 1985

Authors are trying to unveil the ultrastructural organization of olfactory bulb, which has been summerized under light microscopic level or communicated only in some detail in different view point until now. For the critical point of view, since the phylogenetical approach will give the ultimate value in the correlative study between structural and functional bases (Brodal, 1969), the present study was carried out light and electron microscopic analyses of the structures of the neurons and synaptic organizations in olfactory bulbs from different animals in phylogenetical scale. We selected each one species from five animal classes: the house rabbit(Oryctolagus cuniculus var. domesticus [Gmelin]) from Mammalia, the domestic fowl (Gallus gallus domesticus Brisson) from Aves, the viper (Agkistrodon hylys [G.P. Pallas]) from Reptilia, a frog (Bombiana orientalis Boulenger) from Amphibia and the crussian carp (Carassius carassius [Linne]) from Pisces. For light microscopic study, samples were fixed in 10% formalin and paraffin sections were stained with hematoxylin-eosin. For the electron microscopic study, the tissues were fixed by perfusion through the heart or immersion with 1% paraform-aldehyde-glutaraldehyde mixture (phosphate buffer, pH 7.4), and final tissue block trimmed under dissecting microscope were osmicated (1% OsO4), they were embedded in Araldite or Epon 812, and ultrathin sections were made by LKB-V ultratome following the inspection of semi-thin sections stained with toluidine blue-borax solution. Ultra-thin sections contrasted with uranyl acetate and lead citrate were observed with JEM 100CX electron microscope. We have summerized our morphological analyses as follows: 1. The olfactory bulb of rabbit, viper and frog shows the eight layers of fila olfactoria, glomerular, external granular, external plexiform, mitral cell, internal plexiform, internal granular, medullary but domestic fowl shows the five layers of glomerular, fibrillar, mitral, granular and medullary and the three layers of fibrilla, glomerular and medullary in crussian carp. The sharpness of demarcation between the layers shows deferential tendency according to phylogenetical order. 2. Mitral cells of vertebrate have large triangular or oval shape with spherical nuclei which contain not so much chromatin. The cytoplasm contains numerous cell organelles, of which Nissl's bodies or granular endoplasmic reticula arranged as parallel strands. Development of granular endoplasmic reticula were declined as the phylogentical grade is going lower. 3. Tufted cells of all animal are mostly spindle or polygonal contour and contain oval nuclei which located in periphery of cytoplasm. The nuclei of rabbit, fowl, viper and frog has relatively space chromatin, but a nucleus of crussian carp contain irregularly aggregated chromatin in karyoplasm. Their cytoplasmic volume and cell organelle contents are in between those of mitral cell and granular cell. They contain moderate amount of mitochondria, granular endoplasmic reticula, a few Golgi complex, polysomes, lysosome, etc. 4. Granule of cells of all the vertebrate amimals studied exhibit similar features; cells and their dense nuclei show spherical or oval contour, and they have the thin rim of cytoplasm which contain only a few cell organelles. 5. In rabbit, the soma of mitral cells were in contact with boutons with two types of synaptic vesicles, that is, round and flat vesicles, especially flat vesicles in boutons were showing reciprocal synapses. However, in domestic fowls, vipers, frogs and crussian carps, there were found boutons showing only spherical synaptic vesicles. 6. The boutons containing round synaptic vesicles were made contact with the some of tufted cell of olfactory bulb in the rabbits, fowls, vipers and frogs, but no synaptic boutons were observed in soma of tufted cells in crussian carps. In the frogs, there were observed dendrites were contact with the soma of tufted cells. 7. In the neuropils of plexiform, granular and glomerular layers olfactory bulbs in the vertebrate, the synapses were axo-large dendrites, axo-median and small dendrites, dendrodendritic, and axo-axonal contacts. However, in the neuropil of crussian carps, synapses were observed only in glomerular layer.

• Korean Journal of Heritage: History & Science
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• v.51 no.1
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• pp.48-65
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• 2018

The authors of this paper aim to make a record of the construction process, its symbolic meaning, and the changes in the status of the landscape plants at the Pasanseodang according to the Report on the Pasanseodang written by Park Gyu-hyun in 1874. First, the construction of Samgahun Pavilion, which is located in Myo-ri, Habin-myun, Dalsung-gun, Daegu, took about 90 years and spanned the lifetimes of Park Sungsoo, an 11th-generation descendant of Park Paengnyun (1417~1456) through to Park Kyuhyun, a 14th-generation descendant. It was called the shape of dragon, with its head facing the tail (回龍顧尾形), in feng shui. Second, the village of Pahwoe was founded in 1769, the 45th year of the reign of King Yeongjo, by Park Sungsoo for the purpose of socializing with his friends at his thatched home, and was named after his own courtesy name (Samgahun). Park Kwangseok, the second son of Park Sungsoo, built the sarangchae in 1826 and the anchae in 1869 after his marriage (in 1783). Then, Park Kyuhyun, the grandson of Park Kwangseok, built the pond and planted it with lotus flowers, and built the Hayeopjeong in 1874. The Pasanseodang, as the precursor of the Hayeopjeong, may be related with the name of the hillside region behind Samgahun. Third, a quadrangular-shaped pond with a length of 21m and a width of 15m was also built and planted with lotus flowers. In the center of the pond is a small round island that reflects the world view of the Chosun dynasty, i.e. that the sky is round and the landmass is quadrangular. Meanwhile, the name of the Hayeopjeon reflects the value system of aristocrats who lived a life of leisure and artistic indulgence. They called the eastern room "Yeeyeonhun" (怡燕軒) and the western room "Mongyangjae" (蒙養齋), names which embody their wishes for a good life as a member of the nobility and a bright future for one's descendants. Fourth, in Confucian terms, the authors infer the points of view reflected in the kinds of trees that were planted according to Confucian norms (pine tree, lotus, bamboo), the living philosophy of sustainability (willow), the ideology of seclusion and the search for peace of mind (bamboo), and relief efforts for the poor and a life of practicality (chestnut, oak, wild walnut, lacquer). The authors assert that this way of planting trees was a highly effective design feature of landscape architecture that drew on the locational and symbolic significance of the Seodang. Fifth, the majority of the trees that were initially planted withered and were replaced with different species, except for the locust and lotus, at this point. Nevertheless, a review of the process of construction, symbolic meaning, and original architectural landscape of the Samgahun is of value in demonstrating the extended symbolic meaning of their descendants in terms of the practical loss of the function of the Seodang, the values of Feng Sui (red in the east, white in the west, based on the principles of Feng Sui), the function of repelling evils spirits (kalopanax, trifoliate orange), aesthetic and practical values (sweetbrier, apricot, pear, peach, and oriental oak trees), and the prosperity of the family and the timeless value of honest poverty (silk, crape myrtle, and yew trees).

• Journal of The Korean Society of Inherited Metabolic disease
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• v.21 no.1
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• pp.7-14
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• 2021

Purpose: Pseudohypoparathyroidism (PHP) is caused by genetic and epigenetic alteration in the GNAS locus, and characterized by the resistance to multiple hormones and the Albright's hereditary osteodystrophy (AHO) phenotype. This study investigated the phenotypic characteristics and molecular features of PHP. Methods: Eight patients who diagnosed as PHP were enrolled at Pusan National University Children's hospital and clinical features, biochemical and genetic findings were retrospectively reviewed. Results: Of a total of 8 patients, 5 were diagnosed with PHP1a, and 3 were diagnosed with PHP1b. Patients with PHP1a had three different mutations in the GNAS gene, and patients with PHPIb had imprinting defect in differentially methylated regions (DMRs) of the GNAS locus. Two novel GNAS variants were identified in patients with PHP1a, including c.313-2A>T and c.1094G>A. All patients with PHP1a displayed AHO features; short stature (80%), brachydactyly (80%), a round face (80%), obesity (40%), heterotopic ossification (60%), and intellectual disability (60%), whereas only one patient (33.3%) with PHP1b showed AHO feature such as a round face. When phenotypic features between PHP1a and PHP1b patients were compared, patients with PHP1b showed a tendency of higher current height standard deviation scores (SDS) compared to patients with PHP1a, (-3.2±2.1 vs.-1.1±0.8; P=0.06) Conclusions: This study summarizes the phenotypic and genetic features of the PHP patients. Although we found considerable clinical overlap between PHP1a and PHP1b, further long-term follow-up is needed to evaluate the growth and development of children with PHP, as well as the effects of end-organ resistances to endocrine hormones.

• Journal of the Korean earth science society
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• v.44 no.1
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• pp.13-35
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• 2023

Ocean currents play the most important role in causing and controlling global climate change. The water depth of the Yellow Sea is very shallow compared to the East Sea, and the circulation and currents of seawater are quite complicated owing to the influence of various wind fields, ocean currents, and river discharge with low-salinity seawater. The Yellow Sea Warm Current (YSWC) is one of the most representative currents of the Yellow Sea in winter and is closely related to the weather of the southwest coast of the Korean Peninsula, so it needs to be treated as important in secondary-school textbooks. Based on the 2015 revised national educational curriculum, secondary-school science and earth science textbooks were analyzed for content related to the YSWC. In addition, a questionnaire survey of secondary-school science teachers was conducted to investigate their perceptions of the temporal variability of ocean currents. Most teachers appeared to have the incorrect knowledge that the YSWC moves north all year round to the west coast of the Korean Peninsula and is strong in the summer like a general warm current. The YSWC does not have strong seasonal variability in current strength, unlike the North Korean Cold Current (NKCC), but does not exist all year round and appears only in winter. These errors in teachers' subject knowledge had a background similar to why they had a misconception that the NKCC was strong in winter. Therefore, errors in textbook contents on the YSWC were analyzed and presented. In addition, to develop students' and teachers' data literacy, class materials on the YSWC that can be used in inquiry activities were developed. A graphical user interface (GUI) program that can visualize the sea surface temperature of the Yellow Sea was introduced, and a program displaying the spatial distribution of water temperature and salinity was developed using World Ocean Atlas (WOA) 2018 oceanic in-situ measurements of water temperature and salinity data and ocean numerical model reanalysis field data. This data visualization materials using oceanic data is expected to improve teachers' misunderstandings and serve as an opportunity to cultivate both students and teachers' ocean and data literacy.

• Bangmulgwan gwa yeongu (The National Museum of Korea Journal)
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• v.1
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• pp.174-197
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• 2024

Personal ornaments made from precious metals that have been excavated from tombs dating to the Maripgan period (4th-6th century) of the Silla Kingdom are a major subject of analysis in the study of gender and hierarchy among the tomb occupants. Nonetheless, bracelets had been neglected until Ha Daeryong's recent research on determining gender through bracelets attracted attention. Accordingly, an examination and organization of the fundamental elements of Silla bracelets was needed. In response, this paper examines their physical characteristics, appearance, changes over time, and related wearing practices. The data for this study is derived from 176 bracelets, mostly made from silver or gold. Copper and glass bracelets are also included. Many of them were cast in a single-use earthen mold. Even the notched and protruding designs were created by casting rather than carving. Glass bracelets and bracelets with dragon designs were made using molds with round cavities. Excluding those produced using metal sheets, the rest of the bracelets are thought to have been cast in a mold with a long-string-shaped cavity and then bent round. After being bent, the two ends were either soldered together (closed type) or left open (open type). As demonstrated in the study by Lee Hansang, Silla bracelets evolved from plain rounded rod-shaped bracelets, such as the one excavated from the Northern Mound of Hwangnamdaechong Tomb, to versions with notched designs, and eventually to those with protruding designs, which gained popularity by the sixth century. The precedents of plain rounded rod-shaped bracelets are presumed to have been thin rod-shaped bracelets from the Proto-Three Kingdoms period. Bracelets need to be fit to the wrists so that they do not slip off easily when worn. The open type design was the preferable way to achieve this. Moreover, given the ductility of gold, silver, and copper, it seems that it would have been possible to stretch or deform them. In the end, I concluded that even if a bracelet is too small to pass man's hand, the open type could have been worn. Furthermore, if a closed-type bracelet were pressed into an oval shape, it would not be impossible for a man to put it on. When bracelets are divided according to their degree of deformability into type A (the open type) through type D, which is almost impossible to deform, type A is commonly found with wearers of thin hollow earrings, and types C and D (which are difficult to deform) are not found with wearers of thin hollow earrings, but only with wearers of thick hollow earrings. Therefore, it can be seen that men were allowed to wear bracelets, and the existing studies that differentiate between men and women based on the wearing of thin hollow earrings, thick hollow earrings, and swords remain valid.

• Journal of the Korean Society of Costume
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• v.4
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• pp.87-114
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• 1981

A costume reveals the social characteristics of the era in which it is worn, thus we can say that the history of change of the costume is the history of change of the living culture of the era. Since the Three States era, the costume structure of this country had been affected by the costume system of the China's historical dynasties in the form of the grant therefrom because of geographical conditions, which affection was conspicuous for the bureaucrat class, particularly including but not limited to the Kings' familities. Such a grant of the costume for the bureaucrat class (i.e., official uniform) was first given by the Dang-dynasty at the age of Queen Jinduck, the 28th of the Shilla-dynasty. Since then, the costume for the bureaucrats had consecutively been affected as the ages had gone from the unified Shilla, to the Koryo and to the Yi-dynasty. As the full costumes officially used by government officials (generally called "Baek Gwan") in the Yidynasty, there existed Jo-bok, Gong-bok and Sang-bok. Of such official costumes, Gong-bok was worn at the time of conducting official affairs of the dynasty, making a respectful visit for the expression of thanks or meeting diplomatic missions of foreign countries. It appears no study was made yet with regard to the Gong-bok while the studies on the Jo-bok and the Sangbok were made. Therefore, this article is, by rendering a study and research on the styles of costumes of civil servants' stone images erected at the Kings' tombs of the Yi-dynasty, to help the persons concerned understand the Gong-bok, one of the official costume for Baek Kwan of that age and further purports to specifically identify the styles and changes of the Gong-bok, worn by Baek Gwan during the Yi-dynasty, consisting of the Bok-doo (a hat, four angled and two storied with flat top), Po (gown), Dae (belt), and Hol (small and thin plate which was officially held by the government officials in hand, showing the courtesy to and writing brief memorandums before the King) and Hwa (shoes). For that purpose, I investigated by actually visiting the tombs of the Kings of the Yi-dynasty including the Geonwon-neung, the tomb of the first King Tae-jo and the You-neung, the tomb of the 27th King Soon-jong as well as the tombs of the lawful wives and concubines of various Kings, totalling 29 tombs and made reference to relevant books and records. Pursuant. to this study, of the 29 Kings' tombs the costume styles of civil servants' stone images erected at the 26 Kings' tombs are those of Gong-bok for Baek-gwan of the Yi-dynasty wearing Bok-doo as a hat and Ban-ryeong or Dan-ryenog Po as a gown with Dae, holding Hol in hand and wearing shoes. Other than those of the 26 tombs, the costume styles of the Ryu-neung, the tomb of the Moon-jo who was the first son of 23rd King Soon-jo and given the King's title after he died and of the You-neung, the tomb of the 27th King Soon-jong are those of Jobok with Yang-gwan (a sort of hat having stripes erected, which is different from the Bok-doo), and that of the Hong-neung, the tomb of the 26th King Go-jong shows an exceptional one wearing Yang-gwan and Ban-ryeong Po ; these costume styles other than Gongbok remain as the subject for further study. Gong-bok which is the costume style of civil servants' stone images of most of the Kings' tombs had not been changed in its basic structure for about 500 years of the Yi-dynasty and Koryo categorized by the class of officials pursuant to the color of Po and materials of Dae and Hol. Summary of this costume style follows: (1) Gwan-mo (hat). The Gwan-mo style of civil servants' stone images of the 26 Kings' tombs, other than Ryu-neung, Hong-neung and You-neung which have Yang-gwan, out of the 29 Kings' tombs of the Yi-dynasty reveals the Bok-doo with four angled top, having fore-part and back-part divided. Back part of the Bok-doo is double the fore-part in height. The expression of the Gak (wings of the Bokdoo) varies: the Gyo-gak Bok-doo in that the Gaks, roundly arisen to the direction of the top, are clossed each other (tombs of the Kings Tae-jong), the downward style Jeon-gak Bok-doo in that soft Gaks are hanged on the shoulders (tombs of the Kings Joong-jong and Seong-jong) and another types of Jeon-gak Bok-doo having Gaks which arearisen steeply or roundly to the direction of top and the end of which are treated in a rounded or straight line form. At the lower edge one protrusive line distinctly reveals. Exceptionally, there reveals 11 Yang-gwan (gwan having 11 stripes erected) at the Ryu-neung of the King Moon-jo, 9 Yang-gwan at the Hong-neung of the King Go-jong and 11 Yang-gwan at the You-neung of the King Soon-jong; noting that the Yang-gwan of Baek Kwan, granted by the Myeong-dynasty of the China during the Yi-dynasty, was in the shape of 5 Yang-gwan for the first Poom (class) based on the principle of "Yideung Chaegang" (gradual degrading for secondary level), the above-mentioned Yang-gwans are very contrary to the principle and I do not touch such issue in this study, leaving for further study. (2) Po (gown). (a) Git (collar). Collar style of Po was the Ban-ryeong (round collar) having small neck-line in the early stage and was changed to the Dan-ryeong (round collar having deep neck-line) in the middle of the: dynasty. In the Dan-ryeong style of the middle era (shown at the tomb of the King Young-jo); a, thin line such as bias is shown around the internal side edge and the width of collar became wide a little. It is particularly noted that the Ryu-neung established in the middle stage and the You-neung in the later stage show civil servants in Jo-bok with the the Jikryeong (straight collar) Po and in case of the Hong-neung, the Hong-neung, the tomb of the King Go-jong, civil servants, although they wear Yang-gwan, are in the Ban-ryeong Po with Hoo-soo (back embroidery) and Dae and wear shoes as used in the Jo-bok style. As I could not make clear the theoretical basis of why the civil servants' costume styles revealed, at these tombs of the Kings are different from those of other tombs, I left this issue for further study. It is also noted that all the civil servants' stone images show the shape of triangled collar which is revealed over the Godae-git of Po. This triangled collar, I believe, would be the collar of the Cheomri which was worn in the middle of the Po and the underwear, (b) Sleeve. The sleeve was in the Gwan-soo (wide sleeve) style. having the width of over 100 centimeter from the early stage to the later stage arid in the Doo-ri sleeve style having the edge slightly rounded and we can recognize that it was the long sleeve in view of block fold shaped protrusive line, expressed on the arms. At the age of the King Young-jo, the sleeve-end became slightly narrow and as a result, the lower line of the sleeve were shaped curved. We can see another shape of narrow sleeve inside the wide sleeve-end, which should be the sleeve of the Cheom-ri worn under the Gong-bok. (c) Moo. The Moo revealed on the Po of civil servants' stone images at the age of the King Sook-jong' coming to the middle era. Initially the top of the Moo was expressed flat but the Moo was gradually changed to the triangled shape with the acute top. In certain cases, top or lower part of the Moo are not reveald because of wear and tear. (d) Yeomim. Yeomim (folding) of the Po was first expressed on civil servants' stone images of the Won-neung, the tomb of the King Young-jo and we can seemore delicate expression of the Yeomim and Goreum (stripe folding and fixing the lapel of the Po) at the tomb of the Jeongseong-wanghoo, the wife of the King Young-jo, At the age of the King Soon-jo, we can see the shape of Goreum similar to a string rather than the Goreum and the upper part of the Goreum which fixes Yeomim was expressed on the right sleeve. (3) Dae. Dae fixed on the Po was placed half of the length of Po from the shoulders in the early stage. Thereafter, at the age of the King Hyeon-jong it was shown on the slightly upper part. placed around one third of the length of Po. With regard to the design of Dae, all the civil servants' stone images of the Kings' tombs other than those of the Geonwon-neung of the King Tae-jo show single or double protrusive line expressed at the edge of Dae and in the middle of such lines, cloud pattern, dangcho (a grass) pattern, chrysanthemum pattern or other various types of flowery patterns were designed. Remaining portion of the waist Dae was hanged up on the back, which was initially expressed as directed from the left to the right but thereafter expressed. without orderly fashion,. to the direction of the left from the right and vice versa, Dae was in the shape of Yaja Dae. In this regard, an issue of when or where such a disorderly fashion of the direction of the remaining portion of waist Dae was originated is also presented to be clarified. In case of the Ryuneung, Hong-neung and You-neung which have civil servants' stone images wearing exceptional costume (Jo-bok), waist Dae of the Ryu-neung and Hong-neung are designed in the mixture of dual cranes pattern, cosecutive beaded pattern and chrvsenthemum pattern and that of You-neung is designed in cloud pattern. (4) Hol. Although materials of the Hol held in hand of civil servants' stone images are not identifiable, those should be the ivory Hol as all the Baek Gwan's erected as stone images should be high class officials. In the styles, no significant changes were found, however the Hol's expressed on civil servants' stone images of the Yi-dynasty were shaped in round top and angled bottom or round top and bottom. Parcicularly, at the age of the King Young-jo the Hol was expressed in the peculiar type with four angles all cut off. (5) Hwa (shoes). As the shoes expressed on civil servants' stone images are covered with the lower edges of the Po, the styles thereof are not exactly identifiable. However, reading the statement "black leather shoes for the first class (1 Poom) to ninth class (9 Poom)," recorded in the Gyeongkook Daejon, we can believe that the shoes were worn. As the age went on, the front tips of the shoes were soared and particularly, at the Hong-neung of the King Go-jong the shoes were obviously expressed with modern sense as the country were civilized.

• The Journal of the Korean bone and joint tumor society
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• v.7 no.1
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• pp.28-35
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• 2001

Purpose : Authors investigated the efficiency of preoperative MRI in suspicious glomus tumor and the clinical outcomes after marginal excision. Materials and Methods : In 10 cases of glomus tumors in the fingers, authors retrospectively analyzed the clinical data, including previous trauma, treatment history, preoperative symptoms, physical examination, plain radiography, MRI (9 cases), pathological findings and postoperative complications. Results : The patients had pain in 10 cases, tenderness in 9 cases, cold sensitivity in 3 cases and edema in one case. MRI showed low signal (3 cases) or iso-signal (5) intensity on T1 weighted image, high signal intensity (8) on T2 weighted image, and all the lesions were enhanced in gadolinium enhancement images. The exact locations of glomus tumors were median in 6 cases, lateral in 5, lateral fold in 2 and pulp in 3 in transverse section and nail bed in 5 cases and nail matrix in 5 in sagittal section. Marginal excision was performed by lateral approach in one case and transungual in 9 cases. Histologically, all 10 cases were composed of solid sheets of round cells interrupted by thin-walled blood vessels. Most of clinical symptoms were disappeared in all cases after operation. Nail deformity was found in one case, which was originated from nail matrix, however, there was no recurrence. Summary : Clinical symptom was the most impotant factor in diagnosis of glomus tumor in the fingers. However, preoperative MRIs were helpful in patients, who had obscure pain or prolonged clinical symptoms with suspicious glomus tumors. Preoperative MRI might be one of the most useful tools for establishing the exact diagnosis and detecting the location of glomus tumors, in spite of the relatively high expenses.

• The Transactions of the Korea Information Processing Society
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• v.4 no.9
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• pp.2221-2234
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• 1997

Distributed mutual exclusion algorithms have employed two approaches to achieve mutual exclusion and can be divided into two broad classes:token-based and permission-based. Token-based algorithms share a unique token among the nodes and a node is allowed to access its common resources if it possesses the token. Permission-based algorithms require one or more successive rounds of message exchanges among the nodes to obtain the permission to access the common resources. A hypercube architecture has earned wide acceptance in multiprocessor systems in the past few years because of its simple, yet rich topology. Accordingly, we study distributed permission-based mutual exclusion algorithms for hypercubes, and design a distributed permission-based mutual exclusion algorithm based on a new information structure adapted to the hypercubes. The new information structure is a request set of T-pattern from a logical mesh that is embedded into a hypercube. If a node wants to access the common resources, it sends request message to all nodes in the request set by Lan's multicast algorithm. Once the node receives a grant message from all nodes in the request set, it accesses the common resource. We evaluate our algorithm with respect to minimum round-trip delay, blocking delay, and the number of messages per access to the common resource.

• Journal of KIISE:Information Networking
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• v.33 no.3
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• pp.231-246
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• 2006

A server load balancer is used to accept and distribute client requests to one of servers in a wireless internet proxy server cluster. LVS(Linux Virtual Server), a software based server load balancer, can support several load balancing algorithms where client requests are distributed to servers in a round robin way, in a hashing-based way or in a way to assign first to the server with the least number of its concurrent connections to LVS. An improved load balancing algorithm to consider server performance was proposed where they check upper and lower limits of concurrent connection numbers to be allowed within each maximum server performance in advance and apply the static limits to load balancing. However, they do not apply run-time server load information dynamically to load balancing. In this paper, we propose a dynamic load balancing scheme where the load balancer keeps each server CPU load information at run time and assigns a new client request first to the server with the lowest load. Using a cluster consisting of 16 PCs, we performed experiments with static content(image and HTML). Compared to the existing schemes, experimental results show performance improvement in the cases of client requests requiring CPU-intensive processing and a cluster consisting of servers with difference performance.

• Journal of Korean Neurosurgical Society
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• v.59 no.2
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• pp.106-116
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• 2016

Objective : Protein disulfide isomerase (PDI) acts as a chaperone on the cell surface, and it has been reported that PDI is associated with the tumor cell migration and invasion. The aims of this study are to investigate the anti-migration effect of bacitracin, which is an inhibitor of PDI, and the associated factor in this process. Methods : U87-MG glioma cells were treated with bacitracin in 1.25, 2.5, 3.75, and 5.0 mM concentrations. Western blot with caspase-3 was applied to evaluate the cytotoxicity of bacitracin. Adhesion, morphology, migration assays, and organotypic brain-slice culture were performed to evaluate the effect of bacitracin to the tumor cell. Western blot, PCR, and gelatin zymography were performed to investigate the associated factors. Thirty glioma tissues were collected following immunohistochemistry and Western blot. Results : Bacitracin showed a cytotoxicity in 3rd (p<0.05) and 4th (p<0.001) days, in 5.0 Mm concentration. The cell adhesion significantly decreased and the cells became a round shape after treated with bacitracin. The migration ability, the expression of phosphorylated focal adhesion kinase (p-FAK) and matrix metalloproteinase-2 (MMP-2) decreased in a bacitracin dose- and time-dependent manner. The U87-MG cells exhibited low-invasiveness in the 2.5 mM, compared with the untreated in organotypic brain-slice culture. PDI was expressed in the tumor margin, and significantly increased with histological glioma grades (p<0.001). Conclusion : Bacitracin, as a functional inhibitor of PDI, decreased the phosphorylated FAK and the secreted MMP-2, which are the downstream of integrin and play a major role in cell migration and invasion, might become one of the feasible therapeutic strategies for glioblastoma.