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Jung-Wook Kim

Publications and source records attributed to Jung-Wook Kim.

11 recordsLinked to original sources
PubMed2006

Mutational analysis of candidate genes in 24 amelogenesis imperfecta families.

Amelogenesis imperfecta (AI) is a heterogeneous group of inherited defects in dental enamel formation. The malformed enamel can be unusually thin, soft, rough and stained. The strict definition of AI includes only those cases where enamel defects occur in the absence of other symptoms. Currently, there are seven candidate genes for AI: amelogenin, enamelin, ameloblastin, tuftelin, distal-less homeobox 3, enamelysin, and kallikrein 4. To identify sequence variations in AI candidate genes in patients with isolated enamel defects, and to deduce the likely effect of each sequence variation on protein expression and structure, families with isolated enamel defects were recruited. The coding exons and nearby intron sequences were amplified for each of the AI candidate genes by using genomic DNA from the proband as template. The amplification products for the proband were sequenced. Then, other family members were tested to determine their genotype with respect to each sequence variation. All subjects received an oral examination, and intraoral photographs and dental radiographs were obtained. Out of 24 families with isolated enamel defects, only six disease-causing mutations were identified in the AI candidate genes. This finding suggests that many additional genes potentially contribute to the etiology of AI.

Amelogenesis Imperfecta↗
PubMed2006

Porcine SPARC: isolation from dentin, cDNA sequence, and computer model.

Genes encoding the major enamel matrix proteins and non-collagenous proteins of bone and dentin are members of the secretory calcium-binding phosphoprotein (SCPP) family, which originated from ancestral SPARC (secreted protein, acidic and rich in cysteine; BM-40/osteonectin). To better understand the role of SPARC in mineralizing systems, we isolated SPARC from developing pig teeth, deduced its primary structure from the cDNA sequence, and determined its quaternary structure by homology modelling with reference to human SPARC crystal structures. The guanidine/EDTA extract from porcine dentin was fractionated by anion-exchange and size-exclusion chromatography. Stains-all positive bands at 38 and 35 kDa gave the N-terminal sequences APQQEALPDETEV and DFEKNYNMYIFPV, which corresponded to the SPARC N terminus and an internal region of the protein. Porcine SPARC contains 300 amino acids, including the 17-amino acid signal peptide, and shares 96.2% amino acid sequence identity with human SPARC. Without post-translational modifications, the 283-amino acid secreted protein has a molecular mass of 32.3 kDa. The three-dimensional model revealed that porcine SPARC contains a single N-linked glycosylation at N113, seven intramolecular disulfide bridges, and assembles into dimers. SPARC is composed of three structural/functional domains: an acidic Ca2+-binding, a follistatin-like, and an extracellular calcium-binding domain.

Amino Acid Sequence↗
PubMed2006

Porcine dentin matrix protein 1: gene structure, cDNA sequence, and expression in teeth.

Dentin matrix protein 1 (DMP1) is an acidic non-collagenous protein that is necessary for the proper biomineralization of bone, cartilage, cementum, dentin, and enamel. Dentin matrix protein 1 is highly phosphorylated and potentially glycosylated, but there is no experimental data identifying which specific amino acids are modified. For the purpose of facilitating the characterization of DMP1 from pig, which has the advantage of large developing teeth for obtaining protein in quantity and extensive structural information concerning other tooth matrix proteins, we characterized the porcine DMP1 cDNA and gene structure, raised anti-peptide immunoglobulins that are specific for porcine DMP1, and detected DMP1 protein in porcine tooth extracts and histological sections. Porcine DMP1 has 510 amino acids, including a 16-amino acid signal peptide. The deduced molecular weight of the secreted, unmodified protein is 53.5 kDa. The protein has 93 serines and 12 threonines in the appropriate context for phosphorylation, and four asparagines in a context suitable for glycosylation. Dentin matrix protein 1 protein bands with apparent molecular weights between 30 and 45 kDa were observed in partially purified dentin extracts. In developing teeth, immunohistochemistry localized DMP1 in odontoblasts and the dentinal tubules of mineralized dentin and in ameloblasts, but not in the enamel matrix.

Amino Acid Sequence↗
PubMed2004

Mutational hot spot in the DSPP gene causing dentinogenesis imperfecta type II.

The current system for the classification of hereditary defects of tooth dentin is based upon clinical and radiographic findings and consists of two types of dentin dysplasia (DD) and three types of dentinogenesis imperfecta (DGI). However, whether DGI type III should be considered a distinct phenotype or a variation of DGI type II is debatable. In the 30 years since the classification system was first proposed, significant advances have been made regarding the genetic etiologies of inherited dentin defects. DGI type II is recognized as an autosomal dominant disorder with almost complete penetrance and a low frequency of de novo mutations. We have identified a mutation (c.52G-->T, p.V18F) at the first nucleotide of exon 3 of the DSPP (dentin sialophosphoprotein) gene in a Korean family (de novo) and a Caucasian family. This mutation has previously been reported as causing DGI type II in a Chinese family. These findings suggest that this mutation site represents a mutational "hot spot" in the DSPP gene. The clinical and radiographic features of these two families include the classic phenotypes associated with both DGI type II and type III. Finding that a single mutation causes both phenotypic patterns strongly supports the conclusion that DGI type II and DGI type III are not separate diseases but rather the phenotypic variation of a single disease. We propose a modification of the current classification system such that the designation "hereditary opalescent dentin" or "DGI type II" should be used to describe both the DGI type II and type III phenotypes.

Child, Preschool↗
PubMed2004

Porcine dentin sialoprotein is a proteoglycan with glycosaminoglycan chains containing chondroitin 6-sulfate.

Dentin sialoprotein (DSP) is a glycoprotein that is critical for proper tooth dentin formation, but little is known about the nature of its carbohydrate attachments and other post-translational modifications. We have isolated DSP from pig dentin and demonstrate that it is a proteoglycan. Polyclonal antibodies were raised in chicken against recombinant pig DSP, and used to identify native DSP in fractions of tooth dentin proteins extracted from developing pig molars. Amino acid analyses and characterization of lysylendopeptidase cleavage products confirmed that the purified protein was DSP, and that Arg391 is at the DSP C terminus. On SDS-PAGE and on urea gels, DSP appeared as a smear extending from 280 to 100 kDa, but in the presence of beta-mercaptoethanol the top of the DSP smear disappeared. The high molecular weight material was likely comprised of covalent DSP dimers connected by a disulfide bridge at Cys205. Oligosaccharides were released from DSP following N- and O-linked glycosidase digestions, but these digestions had little effect on the apparent molecular weight of DSP on SDS-PAGE, when compared with the significant reduction following chondroitinase ABC digestion. Glycosaminoglycanases with assorted glycosaminoglycan (GAG) cleavage specificities coupled with Western analyses of the cleaved GAG "stubs" demonstrated that the DSP GAG attachments contain chondroitin 6-sulfate, but not keratan sulfate, heparan sulfate, chondroitin, or chondroitin 4-sulfate. DSP binds biotin-labeled hyaluronic acid, and such binding is inhibited by the addition of unlabeled hyaluronic acid. We conclude that DSP is a proteoglycan and that GAG attachments are the predominant structural feature of porcine DSP.

Amino Acid Sequence↗
PubMed2003

Effect of ultrasonic vibration on dentin bond strength and resin infiltration.

PURPOSE: To apply a vibration technique to compare the bond strength and resin penetration depth into the dentin tubules with those gained using conventional techniques. METHODS: Eighty-eight noncarious extracted human permanent molar teeth were sectioned to remove the coronal enamel. They were embedded in a 1-inch PVC pipe with an acrylic resin. The occlusal surfaces were placed so that the tooth and the embedding medium were at the same level to form a single flat surface. The samples were subsequently polished with silicon carbide abrasive papers, and randomly assigned to four groups (n=22). In Groups 1 and 2, Single Bond was used, and in Groups 3 and 4, One-Step was used. Each adhesive system was applied according to its manufacturer's instructions. For Groups 2 and 4, vibration was applied with an ultrasonic scaler for 10 seconds, and the adhesive was light-cured for 10 seconds. The resin composite was condensed onto the prepared surface in two increments using a Teflon mold and each increment was light-cured for 40 seconds. After 24 hours soaking in tap water at room temperature, the specimens were thermocycled, and the shear bond strengths were measured using a universal testing machine. One-way ANOVA test followed by Student-Newman-Keuls test (P < 0.05) were used to analyze the results. To investigate the infiltration patterns of the adhesive materials, the surface of the specimens was examined with electron microscopy. RESULTS: The shear bond strengths of the vibration groups (Groups 2, 4) were significantly higher than those of the non-vibration groups (Groups 1, 3). The shear bond strengths of Single Bond and One-Step were not significantly different. The vibration groups showed greater numbers of resin tags in the tubules and lateral branches under SEM than the non-vibration groups.

Analysis of Variance↗
PubMed2002

Comparison of gene expression at the feto-maternal interface between normal and recurrent pregnancy loss patients.

Normal pregnancy requires a series of immunological, metabolic, vascular and endocrine regulating processes. However, the specific genes and proteins involved in these processes are not well defined. Aberration of these processes may lead to problems in pregnancy. One of these problems may be recurrent pregnancy loss (RPL). Little information is available on the level of expression of genes that may play a role in normal pregnancy. Therefore, this study determined whether different levels of gene expression at the feto-maternal interface could be associated with factors for RPL. The expression patterns of genes isolated from subtractive hybridization analysis performed with chorionic villi from normal and abnormal pregnancies were investigated. Eight genes classified into groups, including immunosuppression-related, embryo attachment-related and angiogenesis-related, were isolated.

Abortion, Habitual↗
PubMed2002

Reposition of intruded permanent incisor by a combination of surgical and orthodontic approach: a case report.

This report presents a case of a completely intrusive luxation of an immature permanent central incisor in a 7 years 9 months-old girl. Because there are severe intrusive trauma and cortical alveolar bone fracture, it was impossible to reposition with orthodontic or surgical method alone. The intruded tooth was repositioned to healthy alveolar bone level by using surgical extrusion and stabilization with sutures and periodontal pack. After healing of adjacent bone, the intruded maxillary central incisor erupted orthodontically by removable orthodontic appliance. It was moved from a high position to level of adjacent tooth in about 7 months. A radiograph was taken 6 months after ceasing forced eruption, which demonstrated minor root resorption, but the alveolar bone height had increased.

Alveolar Process↗