• Title/Summary/Keyword: Membranous

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Ultrastructure of Spermatozoa of a Korean Bitterling, Acheilognathus koreensis (Pisces, Cyprinidae) (한국산 잉어과어류 칼납자루(Acheilognathus koreensis) 정자의 미세구조)

  • Kim, Kgu-Hwan;Kim, Jeong-Ki;Hwang, Ki-Ju
    • Korean Journal of Ichthyology
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    • v.19 no.4
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    • pp.286-291
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    • 2007
  • The bitterling, Acheilognathus koreensis spermatozoon has been examined by electron microscopy. The epididymal spermatozoa of A. koreensis are representing typical characteristic of cyprinid spermatozoa including the lateral insertion of flagellum, the organization of centriolar complex in shallow nuclear fossa and the asymmetrical arrangement of mitochondria. The sperm mid-piece contains a large mitochondrion characteristic enclosed by membranous vesicles. The mitochondria aspect is different from that of other cyprinid spermatozoa, which their mitochondria have a conventional aspect and never fuse to form a mitochondrial derivative. In term of sperm evolution, the fused mitochondria are regarded as the apomorphic character in comparison with the separate mitochondria. The single mitochondrion is not found in cyprinid spermatozoon except for Rodeus and Pungtungia.

Fabrication of PVDF Structures by Near Field Electrospinning

  • Kim, Seong-Uk;Ji, Seung-Muk;Yeo, Jong-Seok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.423.1-423.1
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    • 2016
  • Polyvinylidene fluoride (PVDF) has drawn much attention due to its many advantages. PVDF shows high mechanical strength and flexibility, thermal stability, and good piezoelectricity enabling its application to various fields such as sensors, actuators, and energy transducers. Further studies have been conducted on PVDF in the form of thin films. The thin films exhibit different ionic conductivity according to the number of pores within the film, letting these films to be applied as electrolytes or separators of batteries. Porous PVDF membranes are also easily processed, usually made by using electrospinning. However, a large portion of researches were conducted using PVDF membranes produced by far field electrospinning, which is not a well-controlled experimental method. In this paper, we use near field electrospinning (NFES) process for more controlled, small-scaled, mesh type PVDF structures of nano to micro fibers fabricated by controlling process parameters and investigate the properties of such membranous structures. These membranes vary according to geometrical shape, pore density, and fiber thickness. We then measured the mechanical strength and piezoelectric characteristic of the structures. With various geometries in the fiber structures and various scales in the fibers, these types of structures can potentially lead to broader applications for stretchable electronics and dielectric electro active polymers.

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A MODIFIED "GULL-WING" TYPE INCISION FOR MINIMIZING POSTOPERATIVE COMPLICATIONS IN THE CHIN BONE GRAFT (하악정중부 골채취시 술후 합병증을 최소화하기 위한 변형"gull-wing"형 절개법)

  • Kim, Ji-Hyuck;Lee, Jong-Ho;Lee, Suk-Keun;Kim, Soung-Min
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.31 no.2
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    • pp.161-163
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    • 2005
  • In the reconstruction of the hard tissue defect of the oral cavity, the usefulness of the chin bone graft, one of the intraoral donor site, is gradually increased. The advantages include reduced resorption rate after graft due to its membranous bone nature, relatively ease to harvest under local anesthesia, reduced operative time because of the same operative field, decreased morbidity, and relatively large amount of bone can be harvested compared to other intraoral donor site. It has also postoperative complications including paresthesia of the lip or chin area, discomfort of lower anterior teeth, and facial swelling around chin area. Of these complications, facial swelling occurs more frequently, is more severe as a early postoperative discomfort, and prevents fast recover of patient's social activity since this procedure is generally accomplished in the outpatient base under local anesthesia. So we applied a modified " gull-wing" type incision to minimize this complication, and now we report this simple but effective surgical technique with clinically favorable result.

Primary cilia in energy balance signaling and metabolic disorder

  • Lee, Hankyu;Song, Jieun;Jung, Joo Hyun;Ko, Hyuk Wan
    • BMB Reports
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    • v.48 no.12
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    • pp.647-654
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    • 2015
  • Energy homeostasis in our body system is maintained by balancing the intake and expenditure of energy. Excessive accumulation of fat by disrupting the balance system causes overweight and obesity, which are increasingly becoming global health concerns. Understanding the pathogenesis of obesity focused on studying the genes related to familial types of obesity. Recently, a rare human genetic disorder, ciliopathy, links the role for genes regulating structure and function of a cellular organelle, the primary cilium, to metabolic disorder, obesity and type II diabetes. Primary cilia are microtubule based hair-like membranous structures, lacking motility and functions such as sensing the environmental cues, and transducing extracellular signals within the cells. Interestingly, the subclass of ciliopathies, such as Bardet-Biedle and Alström syndrome, manifest obesity and type II diabetes in human and mouse model systems. Moreover, studies on genetic mouse model system indicate that more ciliary genes affect energy homeostasis through multiple regulatory steps such as central and peripheral actions of leptin and insulin. In this review, we discuss the latest findings in primary cilia and metabolic disorders, and propose the possible interaction between primary cilia and the leptin and insulin signal pathways which might enhance our understanding of the unambiguous link of a cell's antenna to obesity and type II diabetes.

Subcellular Location of Spodpotera Cell-expressed Human HepG2-type Glucose Transport Protein

  • Lee, Chong-Kee
    • Biomedical Science Letters
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    • v.18 no.2
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    • pp.160-164
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    • 2012
  • The baculovirus/insect cell expression system is of great value for the large-scale production of normal and mutant mammalian passive glucose-transport proteins heterologously for structural and functional studies. In most mammalian cells that express HepG2, this transporter isoform is predominantly located at the cell surface. However, it had been reported that heterologous expression of other membrane proteins using the baculovirus system induced highly vacuolated cytoplasmic membranes. Therefore, how a cell responds to the synthesis of large amounts of a glycoprotein could be an interesting area for investigation. In order to examine the subcellular location of the human HepG2 transport proteins when expressed in insect cells, immunofluorescence studies were carried out. Insect cells were infected with the recombinant baculovirus AcNPVHIS-GT or with wild-type virus at a MOI of 5, or were not exposed to viral infection. A high level of fluorescence displayed in cells infected with the recombinant virus indicated that transporters are expressed abundantly and present on the surface of infected Sf21 cells. The evidence for the specificity of the immunostaining was strengthened by the negative results shown in the negative controls. Distribution of the transporter protein expressed in insect cells was further revealed by making a series of optical sections through an AcNPVHIS-GT-infected cell using a confocal microscope, which permits optical sectioning of cell sample. These sections displayed intense cytoplasmic immunofluorecence surrounding the region occupied by the enlarged nucleus, indicating that the expressed protein was present not only at the cell surface but also throughout the cytoplasmic membranous structures.

Evaluation of Cardiac Function Using Radioisotope before and after Open Heart Surgery -Detection of Preoperative Cardiac Shunt and Postoperative Remnant Shunt by Nuclear Angiocardiography- (개심술 전후 방사성 동위원소를 이용한 심기능 평가에 관한 연구 -수술전 shunt 의 진단 및 교정수술후의 성적평가에 대하여-)

  • 서경필
    • Journal of Chest Surgery
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    • v.15 no.2
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    • pp.194-203
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    • 1982
  • In this investigation we undertook to evaluate the utility of radionuclide cardiac angiography in the detection of cardiac shunts before and after surgical correction. Time-activity curves of ventricles and lungs were evaluated after bolus intravenous injection of 99mTc-human serum albumin in 512 preoperative patients and 551 post-operative patients. Omitting 31 cases of technical failure due to poor bolus, we detected shunts in 459 cases of 481 preoperative evaluations, so the detectability was 95.4%. The cases which couldn`t be detected by this method had small amount of shunt. Also the degree of shunt detected by radioisotope methods were well correlated with oxymetry method. [r=0.89, p<0.01 ] In postoperative evaluations, 18 out of 411 patients with left to right shunt and 10 out of 140 right to left shunt were found to have remnant shunts with radionuclide cardiac angiography. Of the 28 cases with failed operation, 2 were confirmed in reoperation, 2 by cardiac catheterization, 2 by two -dimensional echocardiography. All except one .f these patients had membranous ventricular septal defects and those with left to right shunts had moderate to severe pulmonary hypertension and shunt amount. Also those had larger septal defects than control group. We consider that radionuclide cardiac angiography is a simple and noninvasive method which can show the preoperative diagnosis and postoperative follow up of cardiac shunts.

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Molecular Phylogeny of Syngnathiformes Fishes Inferred from Mitochondrial Cytochrome b DNA Sequences (실고기목 어류 (Syngnathiformes)의 분자계통학적 분류)

  • KOH Beom Seok;SONG Choon Bok
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.37 no.5
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    • pp.405-413
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    • 2004
  • The previous morphology-based taxonomic frameworks within the family Syngnathidae had emphasized the significance of the male brood pouch and reproductive biology in defining the group. However, several different hypotheses had been proposed by different investigators. This study has been carried out to determine the phylogenetic relationships among 19 species belonging to the order Syngnathiformes with three Gasterosteiformes species as outgroup taxa by using the mitochondrial cytochrome b DNA sequences. Phylogenetic analyses based on neighbor-joining distance, maximum parsimony, minimum evolution and maximum likelihood method strongly supported that the family Syngnathidae, the suborder Syngnathoidei and the order Syngnathiformes were all monophyletic group. Although much of previous morphological analyses were supported by our molecular data, there were some significant discrepancies between molecular and morphological work. Such an interesting result was that the weedy seadragon (Phyllopteryx taeniolatus) strongly grouped together with the New Zealand pot-belly seahorse (Hippocampus abdominalis). Considering the markedly different brooding structure between them, this unexpected result might be explained whether by multiple independent origins of brooding structure or by hybridization between the female Hippocampus and other syngnathid species having individual membranous egg compartment. In addition, the suborder Aulostomoidei was paraphyletic group because the shrimpfish (Aeliscus strigatus), belonging to the family Centriscidae, always grouped together with the family Syngnathidae as a sister taxon.

Surgical Correction of Cor Triatriatum Associated with Pulmonary Artery Thrombosis in an Adult

  • Park, Jae-Bum;Shin, Je-Kyoun;Chee, Hyun-Keun;Kim, Jun-Seok;Ko, Sung-Min;Song, Meong-Gun
    • Journal of Chest Surgery
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    • v.44 no.6
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    • pp.432-436
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    • 2011
  • We herein present a case of a successful correction of cor triatriatum associated with thrombotic pulmonary hypertension diagnosed in an adult female patient. We confirmed diagnosis using transthoracic and transesophageal echocardiography in addition to cardiac computed tomography and magnetic resonance imaging. Surgical repair comprised excision of the fibromuscular membranous septum in the left atrium, patch closure of an atrial septal defect, and reconstruction of the pulmonary arteries with a vascular graft. Cor triatriatum complicated pulmonary thrombotic hypertension with atrial septal defect is amenable to surgical correction with satisfactory results.

Effect of SOD on Ultrastructural Changes of Gastric Parietal Cells in the Cisplatin Treated Rats (흰쥐에서 cisplatin에 의한 위벽세포의 미세구조변화에 미치는 SOD의 영향)

  • Paik, Doo-Jin;Park, Kyu-Wan;Chung, Ho-Sam
    • Applied Microscopy
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    • v.26 no.3
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    • pp.315-328
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    • 1996
  • This study aims to demonstrate the effect of SOD (superoxide dismutase), one of the antioxidant enzymes, on the ultrastructural changes in the parietal cells caused by the administration of cisplatin in the rat. A total of 60 healthy Sprague-Dawley rats weighing about 200 gm were used as experimental animals. Cisplatin (6 mg/kg) was administered intraperitoneally to rats pretreated with 15,000 unit/kg of SOD or rats without the pretreatment. The experimental animals were sacrificed at 6 hours, 12 hours, 24 hours and 3 days after the administration of cisplatin. The results were as follows: 1. SOD alone did not affect the ultrastructural changes in the gastric parietal cells in the rat. 2. Irregular shaped mitochondria, mitochondria with dim cristae, dilated cristae, ruptured outer membrane, electron lucent matrix and degenerative mitochondria were seen in cisplatin treated rat. Whorled membranous body, many lysosomes and large vacuole were observed in the gastric parietal cells in cisplatin treated rat. 3. Mitochondria with dilated cristae and electron lucent matrix and irregular shaped mitochondria were observed in the gastric parietal cells of the cisplatin treated rat with pretreatment of SOD. These results suggest that SOD attenuates the toxic effect of the cisplatin in the gastric parietal cells of the rat.

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A Case of Immunoglobulin A Nephropathy in a Patient with Kimura's Disease

  • Park, Hye Jung;Kim, Jae Kyung;Kim, Hyun Ju;Park, Kwan-Kyu;Bae, Yoon Sung;Lee, Yong Kyu;Kim, Beom Seok
    • Journal of Yeungnam Medical Science
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    • v.30 no.2
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    • pp.149-151
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    • 2013
  • Kimura's disease is an angiolymphoid-proliferative disorder that manifests with benign subcutaneous swelling predominantly in the head and the neck. Kidney involvement, including proteinuria, occurs in 12-16% of patients with the disease, and 60-78% of such cases is nephrotic syndrome. Reported etiologies of nephrotic syndrome in Kimura's disease include membranous glomerulonephritis, mesangial proliferative glomerulonephritis, minimal-change disease, focal segmental glomerulosclerosis, diffuse proliferative glomerulonephritis and immunoglobulin A (IgA) nephropathy. There have been only two case reports of IgA nephropathy in Kimura's disease, in 1998. In this report, we present a third case of IgA nephropathy associated with Kimura's disease.