• Journal of Microbiology
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• v.44 no.6
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• pp.641-648
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• 2006

We previously reported that Skp1, a component of the Skp1-Cullin-F-box protein (SCF) complex essential for the timely degradation of cell cycle proteins by ubiquitination, physically interacts with Bfa1, which is a key negative regulator of the mitotic exit network (MEN) in response to diverse checkpoint-activating stresses in budding yeast. In this study, we initially investigated whether the interaction of Skp1 and Bfa1 is involved in the regulation of the Bfa1 protein level during the cell cycle, especially by mediating its degradation. However, the profile of the Bfa1 protein did not change during the cell cycle in skp1-11, which is a SKP1 mutant allele in which the function of Skp1 as a part of SCF is completely impaired, thus indicating that Skp1 does not affect the degradation of Bfa1. On the other hand, we found that the skp1-12 mutant allele, previously reported to block G2-M transition, showed defects in mitotic exit and cytokinesis. The skp1-12 mutant allele also revealed a specific genetic interaction with ${\Delta}bfa1$. Bfa1 interacted with Skp1 via its 184 C-terminal residues (Bfa1-D8) that are responsible for its function in mitotic exit. In addition, the interaction between Bfa1 and the Skp1-12 mutant protein was stronger than that of Bfa1 and the wild type Skp1. We suggest a novel function of Skp1 in mitotic exit and cytokinesis, independent of its function as a part of the SCF complex. The interaction of Skp1 and Bfa1 may contribute to the function of Skp1 in the mitotic exit.

• Journal of Microbiology
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• v.45 no.3
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• pp.227-233
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• 2007

In budding yeast, septin plays as a scaffold to recruits protein components and regulates crucial cellular events including bud site selection, bud morphogenesis, Cdc28 activation pathway, and cytokinesis. Phosphorylation of Bni5 isolated as a suppressor for septin defect is essential to Swe1-dependent regulation of bud morphogenesis and mitotic entry. The mechanism by which Bni5 regulates normal septin function is not completely understood. Here, we provide evidence that Bni5 phosphorylation is important for interaction with septin component Cdc11 and for timely delocalization from septin filament at late mitosis. Phosphorylation-deficient bni5-4A was synthetically lethal with $hof1{\Delta}$. bni5-4A cells had defective structure of septin ring and connected cell morphology, indicative of defects in cytokinesis. Two-hybrid analysis revealed that bni5-4A has a defect in direct interaction with Cdc11 and Cdc12. GFP-tagged bni5-4A was normally localized at mother-bud neck of budded cells before middle of mitosis. In contrast, at large-budded telophase cells, bni5-4A-GFP was defective in localization and disappeared from the neck approximately 2 min earlier than that of wild type, as evidenced by time-lapse analysis. Therefore, earlier delocalization of bni5-4A from septin filament is consistent with phosphorylation-dependent interaction with the septin component. These results suggest that timely de localization of Bni5 by phosphorylation is important for septin function and regulation of cytokinesis.

• Journal of the korean academy of Pediatric Dentistry
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• v.25 no.3
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• pp.555-561
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• 1998

Hypophosphatasia is a rare metabolic disorder which manifests characteristics such as abnormal mineralization of bone and dental tissues, diminished serum and tissue alkaline phosphatase, and increased urinary secretion of PEA. It inherited as an autosomal recessive or dominant trait and occurs in all races. In general, hypophosphatasia can be classified in 4 subtypes which are the perinatal, infantile, childhood, adult type depending upon the age at presentation and severity. In young children with Hypophosphatasia the long bones show irregular defects, and the skull showes poor calcification. In older children with premature closure of the skull sutures there may be multiple lucent area called gyral or convolutional markings, described as resembling beaten copper, presumably resulting from increased intracranial pressure. Examination of the jaws reveals a generalized lucency of the maxilla and mandible. the cortical bone and lamina dura are thin, and the alveolar bone may be deficient. Clinical features of Hypophosphatasia include premature loss of deciduous teeth, especially incisors, hypoplasia or aplasia of root cementum, enamel hypoplasia, irregular calcification of dentin, large pulp chamber, and resorption of marginal alveolar bone and roots. Our report involves a patient with a chief complaint of early loss of both Mx. and Mn. deciduous incisors. After conducting a through clinical and radiographic examination this patient was referred to pediatrics under the suspicion of hypophosphatasia, the diagnosis proved to be correct and successful results were accomplished through a denture made to improve esthetics and function.

• Journal of Microbiology and Biotechnology
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• v.20 no.2
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• pp.415-424
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• 2010

The purpose of this study was to investigate the relationship between the global regulatory mechanism known as quorum sensing and expression of virulence factors in Escherichia coli O157:87. A nonpolar luxS deletion was introduced into the chromosome of strain CI03J, a human clinical isolate from South Korea, to create the ${\Delta}luxS$ mutant strain ML03J. Phenotypic characterization of wild-type and mutant strains demonstrated that ML03J had no obvious growth or metabolic defects on 0.2% glucose LB medium, produced a functionally defective flagellum, and could not utilize sorbose; the biological significance of sorbose utilization is unknown. Omics-based analysis revealed the involvement of LuxS in the transcriptional activation of several flagella/chemotaxisrelated genes (flhD; fliA, C, D, S, Z; and cheA, Y, Z), repression of glutamate-dependent acid resistance genes (gadAB), and expression of virulence factors including Shiga toxin, hemolysin, and SepD within the LEE pathogenicity island.

• Journal of Korean Neurosurgical Society
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• v.48 no.3
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• pp.251-258
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• 2010

Objective : Despite rapid evolution of shunt devices, the complication rates remain high. The most common causes are turning from obstruction, infection, and overdrainage into mainly underdrainage. We investigated the incidence of complications in a consecutive series of hydrocephalic patients. Methods : From January 2002 to December 2009, 111 patients underwent ventriculoperitoneal (VP) shunting at our hospital. We documented shunt failures and complications according to valve type, primary disease, and number of revisions. Results : Overall shunt survival time was 268 weeks. Mean survival time of gravity-assisted valve (GAV) was 222 weeks versus 286 weeks for other shunts. Survival time of programmable valves (264 weeks) was longer than that of pressure-controlled valves (186 weeks). The most common cause for shunt revision was underdrainage (13 valves). The revision rate due to underdrainage in patients with GAV (7 of 10 patients) was higher than that for other valve types. Of 7 patients requiring revision for GAV underdrainage, 6 patients were bedridden. The overall infection rate was 3.6%, which was lower than reported series. Seven patients demonstrating overdrainage had cranial defects when operations were performed (41%), and overdrainage was improved in 5 patients after cranioplasty. Conclusion : Although none of the differences was statistically significant, some of the observations were especially notable. If a candidate for VP shunting is bedridden, GAV may not be indicated because it could lead to underdrainage. Careful procedure and perioperative management can reduce infection rate. Cranioplasty performed prior to VP shunting may be beneficial.

• Journal of the korean academy of Pediatric Dentistry
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• v.25 no.4
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• pp.704-709
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• 1998

Amelogenesis imperfecta represents a group of hereditary conditions that manifest enamel defects without evidence of generalized or systemic disorders. These enamel disorders are apparently heterogeneous in the basic chemical structure, resulting in a diverse presentation of clinical characteristics. The reported prevalence of amelogenesis imperfecta varies from 1 in 14,000-16,000 to 1.4 in 1,000 depending on specific population studied with the autosomal dominant hypocalcification type of amelogenesis imperfecta believed to be the least prevalent. The most widely accepted current classification system for delineating the amelogenesis imperfecta types considers the mode of inheritance and clinical manifestations. Three major groups are recognized; hypoplastic, hypocalcified, and hypomaturation types. Delineating specific types of amelogenesis imperfecta can be confusing due to the phenotypical similarity of many forms and that the most recent classification lists 14 different types. A 12 year-old female patient came to our pediatric dentistry clinic complaining of the ugly shape and color of her teeth, especially the upper front area. Although the goal of the treatment was mainly focused on the improvement of patient's esthetics, longevity of the restorations was also considered in selecting the appropriate restorative system, resin jacket crown, which can satisfy the both aspects.

• Tuberculosis and Respiratory Diseases
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• v.53 no.4
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• pp.457-462
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• 2002

Karagener's syndrome is an inherited condition characterized by triad of chronic paranasal sinusitis, situs inversus, and bronchiectasis, Since 1976, Afzelius found a lack of dynein arm in immotile spermatozoa by electron microscopy, numerous recent studies have focused on the ultrastructural defect in the cilia and reported that the variety type of ultrastructural defect in immotile cilia syndrome. We report a female patient who had the Katagener's triad with rare multiple ultrastructural defect of cilia in one patient. The electron microscopic examination showed partial dynein arm defect, loss of radial spoke, microtubular transposition, and giant cilia.

• Journal of Environmental Science International
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• v.29 no.4
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• pp.415-421
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• 2020

This study was conducted to determine the optimum conditions for the treatment of polyamine to promote pollen germination and improve the fruiting rate by overcoming fertilization defects in low-temperature strawberry cultivation. The optimum temperature for pollen germination of strawberries was 30 ℃ for Seolhyang and 25 ℃ for Maehyang, and Seolhyang had a higher pollen germination rate than that of Maehyang. The addition of polyamines, namely spermine and putrescine to the medium improved the pollen germination rate and spermine treatment showed a better effect than putrescine treatment. The proper polyamine type and treatment concentration for enhancing the potency of pollen germination was 500 μM of spermine for both Seolhyang and Maehyang, which improved the pollen germination rate by 19-23% compared with that of the control. However, combined treatment of spermine and putrescine, resulted in a lower germination rate lower than that of the single treatment. Our results indicated that the treatment of polyamines during flowering in protected cultivation of strawberrise can improve the fruiting rate by overcoming the problem of poor pollen germination due to low temperature.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.3 no.1
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• pp.89-92
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• 2000

Acute gastric volvulus is uncommon but surgically emergent. Normally, the stomach is held in position by four ligaments: gastrophrenic, gastrohepatic, gastrosplenic, and gastrocolic. In addition, relative fixation of the pylorus and esophagus provides further anchorage. A normal diaphragm also helps to prevent abnormal displacement of abdominal viscera and development of gastric volvulus. Volvulus may be organoaxial, mesenteroaxial, or a combination of both. Organoaxial volvulus is the rotation of the stomach around an axis extending from the hiatus of the diaphragm to the pylorus. Mesenteroaxial volvulus is the rotation of the stomach around an axis transecting the lesser and greater curvatures of the stomach. The symptoms of gastric volvulus depend on its type, the extent and degree of rotation and obstruction, and associated defects. Classic clinical features of acute gastric volvulus, as by Borchardt in 1904, include unproductive retching, acute, localized epigastric distention, and the inability to pass a NG tube. The presence and severity of these features depend on the degree of gastric obstruction of both the gastroesophageal junction and pyloric outlet. It may be suspected on plain abdominal radiographs and usually confirmed by upper gastrointestinal series. Acute volvulus requires immediate surgical repair, fixation to avoid recurrence, and correction of any underlying anatomic abnormality. Any associate defect should be repaired and the stomach must be fixed. The authors report a case of an 3-year-old girl who had a mesenterioaxial gastric volvulus.

• Journal of Trauma and Injury
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• v.26 no.3
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• pp.175-182
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• 2013

Purpose: Crushing injuries by car tires result from a combination of friction, shearing, and compression forces and the severity of injury is influenced by the acceleration. Because car-tire injuries of the lower leg in children are common these days but they have received little attention; thus, our purpose was to look closely into this problem. Methods: A retrospective analysis was conducted of data from children under 15 years old age who visited an emergency department because of a car-tire-related crushing injury to the lower leg in pedestrian traffic accident from January 2008 to September 2012. The patient's age, sex, site of injury, degree of injury, associated injuries, type of surgery, and complications were reviewed. Results: There were 39 children, the mean age was 8.0 years, and 71.8% were boys. The dorsal part of the leg was involved most frequently. According to the severity classification, 15 children were grade I, 6 were grade II, and 18 were grade III. Among 24 patients, 13 were treated with skin graft and 3 were treated using a sural flap. Twelve patients developed complications, such as hypertrophic scarring, contractures, and deformities with significant bone loss. Conclusion: Various degrees of skin or soft tissue defects were caused in children by car tires. In this study, patients were often also had tendon or bone damage. Proper and timely initial treatments are needed to reduce the incidence of infection, the number of operative procedures, and the hospital stay.