• The Journal of Korea Assosiation for Disability and Oral Health
• /
• v.4 no.1
• /
• pp.12-16
• /
• 2008

Williams syndrome is a rare genetic disorder with a frequency of one per 20,000~50,000 live births. It is caused by a deletion of one elastin allele located within chromosome subunit 7q11.23(long arm). This syndrome is frequently accompanied by disorders such as congenital heart disease, facial anomalies, mental retardation, and so on. The characteristic facial appearance includes full lips, rounded cheeks, broad forehead, periorbital fullness, flattened bridge of nose, small nose with anteverted nostril, long filtrum and low-set ears. In oral features, hypodontia, high prevalence of dental caries, microdontia, enamel hypoplasia, delayed eruption, and malocclusions have been found. Most adult patients with Williams syndrome lack social adaptability and lead seclusive lives, however, young patients are rather very friendly and talkative, and seem smarter than their actual intellectual quotients. They also tend to favor staying with grown-ups rather than mixing with their peers, and tend to present problematic temper tantrum during dental treatment.

• Journal of Genetic Medicine
• /
• v.11 no.1
• /
• pp.36-39
• /
• 2014

Chromosome 3 (3p) deletion syndrome is a rare genomic disorder caused by a deletion at the terminal end of the short arm of chromosome 3. The primary characteristics of the syndrome are delayed development, dysmorphic features, and several other congenital anomalies. Here, we describe the case of a 2-year-old Korean girl with typical features of 3p deletion syndrome, including dysmorphic facial features, low birth weight, developmental delay, growth and cognitive retardation, and congenital heart disease. This case represents the first report of 3p deletion syndrome in Korea. Although phenotypes can be variable among patients, a clinically recognizable pattern has been described for this genetic defect, and our report helps to identify other cases with 3p deletion syndrome from a clinical and genetic perspective.

• Clinical and Experimental Pediatrics
• /
• v.57 no.6
• /
• pp.251-256
• /
• 2014

Severe intraventricular hemorrhaging (IVH) in premature infants and subsequent posthemorrhagic hydrocephalus (PHH) causes significant mortality and life-long neurological complications, including seizures, cerebral palsy, and developmental retardation. However, there are currently no effective therapies for neonatal IVH. The pathogenesis of PHH has been mainly explained by inflammation within the subarachnoid spaces due to the hemolysis of extravasated blood after IVH. Obliterative arachnoiditis, induced by inflammatory responses, impairs cerebrospinal fluid (CSF) resorption and subsequently leads to the development of PHH with ensuing brain damage. Increasing evidence has demonstrated potent immunomodulating abilities of mesenchymal stem cells (MSCs) in various brain injury models. Recent reports of MSC transplantation in an IVH model of newborn rats demonstrated that intraventricular transplantation of MSCs downregulated the inflammatory cytokines in CSF and attenuated progressive PHH. In addition, MSC transplantation mitigated the brain damages that ensue after IVH and PHH, including reactive gliosis, cell death, delayed myelination, and impaired behavioral functions. These findings suggest that MSCs are promising therapeutic agents for neuroprotection in preterm infants with severe IVH.

• Journal of Yeungnam Medical Science
• /
• v.25 no.2
• /
• pp.139-144
• /
• 2008

Crohn's disease is a chronic inflammatory bowel disease that mainly affects children and young adults. Its cause remains unknown. The incidence of pediatric Crohn's disease is increasing, so it is important for clinicians to be aware of the presentation of this disease in the pediatric population. The majority of patients complain of abdominal pain (72%), with only 25% presenting with the 'classical triad' of abdominal pain, weight loss, and diarrhea. Many children with Crohn's disease present in a 'non-classical' manner, with vague complaints such as lethargy or anorexia, which may be associated with only mild abdominal discomfort. Other symptoms include fever, nausea, vomiting, growth retardation, malnutrition, delayed puberty, psychiatric symptoms, arthropathy, and erythema nodosum. Severe constipation and abdominal distension are uncommon symptoms at diagnosis. We report a case of pediatric Crohn's disease, which was diagnosed after the patient presented with severe constipation and abdominal distension.

• Korean journal of food and cookery science
• /
• v.8 no.3
• /
• pp.281-289
• /
• 1992

The physicochemical, rheological and sensory characteristics of Backsulgies added with dietary fibers-cellulose, pectin and wheat bran-were investigated. The maximum acceptable ratio of fibers was 10% for wheat bran or cellulose, 3% for pectin. As me results of physicochemical analysis, cellulose and pectin had larger water-binding capacity man wheat bran. Swelling power was increased with temperature increment. But the type of added dietary fiber did not make significant differences. The degree of gelatinization was measured by maltose content. The retrogradation of backsulgies was significantly delayed by the addition of dietary fibers. The retardation effect of dietary fibers for retrogradation of backsulgies was also proved by textural analysis and time constant determination of Avrami equation. Pectin had especially excellent delaying effect while me storage time extended. There were no significant differences in sensory characteristics between me backsulgi with no dietary fibers and backsulgies added with cellulose 3%, pectin 1% and wheat bran 3%. Therefore, we concluded mat cellulose 3%, pectin 1% and wheat bran 3% were me optimum addition ratios, which have the delaying effect of retrogradation, and which could be accepted as same as conventional backsulgies organoreptically.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2009.03a
• /
• pp.1183-1189
• /
• 2009

The sedimentation rate of particles in a suspension is a function of particle size, initial slurry water content and salinity. Many researches conducted on the behavior of dredged soils have centered on such factors. However, there have been few attempts to assess another important influence factor of seasonal water temperature on designing the placement of dredged materials. In this paper, the effect of seasonal water temperature on sedimentation characteristics of dredged clay was investigated with consideration of three different water temperatures, that are $5^{\circ}C$, $15^{\circ}C$, $35^{\circ}C$, which represent critical water temperatures in winter, spring or fall, and summer, respectively. A series of experimental results reveal that the sedimentation rates for the water temperature of $15^{\circ}C$ and $35^{\circ}C$ are very similar each other, but that of $5^{\circ}C$ that represents a winter season leads to a considerably delayed sedimentation compared to the others. This may be attributable to the retardation of ion-leaching from clay particles at low water temperature.

• Journal of Ocean Engineering and Technology
• /
• v.7 no.1
• /
• pp.124-132
• /
• 1993

In order to examine the effect of anisotropy and stress ratio on fatigue crack propagation rate and opening-closing behavior and also arrest behavior by single tension peak overload, the fatigue tests of constant amplitude atress and single tension peak overload adding to cycle of constant amplitude were carried out in stress ratio of -0.4, -0.2, and 0.4 with materials of T-L and L-T directions in 2024-T3 aluminum alloy plate. Crack opening-closing begavior were measured by the compliance method using COD gage and strain gage. In case of the crack opening-closing behavior was measured by strain gage, the effect of stress ratio is unchangeable. But in the case of COD gage, that is remarkably decreased. Fictitious effective stress intensity factor(U sub(f)) and effective stress intensity factor ratio(U) in L-T direction was higher than those in T-L direction and also threshold arrest overload ratio incrased as stress ratio decreased and that of T-L direction was higher than that in L-T direction.

• Journal of Genetic Medicine
• /
• v.16 no.1
• /
• pp.1-9
• /
• 2019

Noonan syndrome (NS) and NS-related disorders (cardio-facio-cutaneous syndrome, Costello syndrome, NS with multiple lentigines, or LEOPARD [lentigines, ECG conduction abnormalities, ocular hypertelorism, pulmonic stenosis, abnormal genitalia, retardation of growth and sensory neural deafness] syndrome) are collectively named as RASopathies. Clinical presentations are similar, featured with typical facial features, short stature, intellectual disability, ectodermal abnormalities, congenital heart diseases, chest & skeletal deformity and delayed puberty. During past decades, molecular etiologies of RASopathies have been growingly discovered. The functional perturbations of the RAS-mitogen-activated protein kinase pathway are resulted from the mutation of more than 20 genes (PTPN11, SOS1, RAF1, SHOC2, BRAF, KRAS, NRAS, HRAS, MEK1, MEK2, CBL, SOS2, RIT, RRAS, RASA2, SPRY1, LZTR1, MAP3K8, MYST4, A2ML1, RRAS2). The PTPN11 (40-50%), SOS1 (10-20%), RAF1 (3-17%), and RIT1 (5-9%) mutations are common in NS patients. In this review, the constellation of overlapping clinical features of RASopathies will be described based on genotype as well as their differential diagnostic points and management.

• Journal of the Korean Ceramic Society
• /
• v.34 no.2
• /
• pp.163-170
• /
• 1997

The retarding effects of MgSiF6.6H2O on the hydration of portland cement were studied. The setting time, flow value and compressive strength of mortar were measured and the mechanism of retardation was also studied by ion concentration in solution, SEM, BET, and X-ray diffraction. The results are as follows ; 1. Setting time was delayed by the addition of MgSiF6.6H2O. 2. The flow value of mortar decreases depending upon the amount of MgSiF6.6H2O. 3. The compressive strength was almost same or some increase on 28 days hydration. 4. The main retardation mechanism of MgSiF6 on the hydration of portland cement may be explained by the following hypothesis. MgSiF6 depressing the Ca++ and K+ ion concentration of cement paste solution be-cause of the recrystalization of K2SiF6 and CaF2 phase. The new products of K2SiF6 and CaF2 deposit on the surface of unhydrated cement powder and harzard the mass transfer through these layer. The low con-centration of Ca++, K+ ion in solution was decreasing the hydration rate of portland cement.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.27 no.1
• /
• pp.70-76
• /
• 2000

Congenital biliary atresia with progressive sclerosis of the intra- and extra-hepatic duct system occurs in 1 : 10,000 live births, and has a poor prognosis with an expected survival of less than 5 years. Etiology of biliary atresia is unclear, however, it is believed a genetic or developmental cause. The clinical characteristics include pronounced jaundice, hepatosplenomegaly, pruritus, steatorrhea, xanthomas, growth retardation, portal hypertension, bleedings, ascites and respiratory infections. Oral manifestations have seldom been reported in patients with biliary atresia, but there may be enamel hypoplasia, delayed tooth eruption, and green teeth. Early diagnosis and surgical intervention have decreased morbidity. returned growth and development to normal and improved the prognosis for survival. Authors report the clinical and radiologic characteristics, proper managements about two cases with biliary atresia.