Nucleotide Excision Repair Gene ERCC2 and ERCC5 Variants Increase Risk of Uterine Cervical Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Defects in the DNA damage repair process can cause genomic instability and play an important role in cervical carcinogenesis. The purpose of this study was to analyze the association of 29 candidate single nucleotide polymorphisms (SNPs) in genes in the DNA repair pathway, TP53, and TP53BP1 with the risk of cervical cancer. MATERIALS AND METHODS: Twenty-nine SNPs in four genes in the DNA repair pathway (ERCC2, ERCC5, NBS1, and XRCC1), TP53, and TP53BP1 were genotyped for 478 cervical cancer patients and 922 healthy control subjects, and their effects on cervical carcinogenesis were analyzed. RESULTS: The most significant association was found for rs17655 in ERCC5, with an age-adjusted p-value < 0.0001, for which a strong additive effect of the risk allele C was observed (odds ratio, 2.01 for CC to GG). On the other hand, another significant polymorphism rs454421 in ERCC2 showed a dominant effect (odds ratio, 1.68 for GA+AA to GG) with an age-adjusted p-value of 0.0009. The association of these polymorphisms remained significant regardless of the age of onset. The significant result for rs17655 was also consistent for subgroups of patients defined by histology and human papillomavirus (HPV) types. However, for rs454421, the association was observed only in patients with squamous cell carcinoma and non-HPV 18 type. CONCLUSION: The results of this study show a novel association of cervical cancer and the genes involved in the nucleotide excision pathway in the Korean population.

Stemness Evaluation of Mesenchymal Stem Cells from Placentas According to Developmental Stage: Comparison to Those from Adult Bone Marrow

This study was done to evaluate the stemness of human mesenchymal stem cells (hMSCs) derived from placenta according to the development stage and to compare the results to those from adult bone marrow (BM). Based on the source of hMSCs, three groups were defined: group I included term placentas, group II included first-trimester placentas, and group III included adult BM samples. The stemness was evaluated by the proliferation capacity, immunophenotypic expression, mesoderm differentiation, expression of pluripotency markers including telomerase activity. The cumulative population doubling, indicating the proliferation capacity, was significantly higher in group II (P<0.001, 31.7+/-5.8 vs. 15.7+/-6.2 with group I, 9.2+/-4.9 with group III). The pattern of immunophenotypic expression and mesoderm differentiation into adipocytes and osteocytes were similar in all three groups. The expression of pluripotency markers including ALP, SSEA-4, TRA-1-60, TRA-1-81, Oct-4, and telomerase were strongly positive in group II, but very faint positive in the other groups. In conclusions, hMSCs from placentas have different characteristics according to their developmental stage and express mesenchymal stemness potentials similar to those from adult human BMs.

Iatrogenic chemical burn on facial skin by 37% phosphoric acid etchant / 대한치과보존학회지

When we use the total-etch dentin adhesive system for composite resin restorations, gel or liquid acid etchant such as 37% phosphoric acid is commonly used. Thirty seven percentage phosphoric acid is very powerful erosive agent, and can cause severe harmful effects when it contacts with an oral mucosa and facial skin. This case describes iatrogenic chemical burn on facial skin caused by phosphoric acid which was happened during composite resin restorative procedure. Chemical burn by acid etchant can be evoked by careless handling of remnant and syringe. In order to prevent these iatrogenic injuries, we should check the complete removal of the etching agent both in intra and extra-oral environments after etching and rinsing procedure and it is necessary to use of the rubber dam or isolation instruments. If accidental burn were occurred, immediate wash with copious water. And bring the patient to the dermatologist as soon as possible.

Effect of the bleaching light on whitening efficacy / 대한치과보존학회지

The aim of this study was to evaluate the influence of light energy on the tooth whitening effect of bleaching agent in vitro. Extracted human mandibular molars were sectioned to 2 fragments(mesial, distal) and lingual portions of crown were used in this study. All specimens were stained using a red wine for 24 hours and immersed in artificial saliva. Specimens divided into four groups, group 1 and 2 light-activated by LumaCool (LED, LumaLite, Inc., Spring Valley, USA), group 3 and 4 light-activated by FlipoWhite2 (Plasma acr lamp, Lokki, Australia). Group 1 and 3 bleached with LumaWhite(LumaLite, Inc., Spring Valley, USA), group 2 and 4 bleached with Polaoffice(SDI, Victoria, Australia). Bleaching treatment performed during 10 minutes every 24 hours and repeated 6 times. During bleaching treatment , distal fragments was light-activated(L) but mesial fragments was not(NL). Shade assessment employed before and after bleaching treatment using spectrophotometer. The results of the change in shade was compared and analysed between NL and L by using paired-sample T test with 95% level of confidence. There were no significant differences between NL and L with a few exceptions. In group 2, a* value more change in L, in group 3, b* value more change in L, in group 4, a* value less change in L. After bleaching, L* value and DeltaE increased in all groups and the value of a* and b* decreased in all groups. Within the limitation of this test conditions, the results of this study indicate that the light energy has no obvious improving impact on the tooth whitening effect of a bleaching agent.

Inhibitory Effect of IFN-beta, on the Antitumor Activity of Celecoxib in U87 Glioma Model

OBJECTIVE: Interferon-beta, (IFN-beta) has been used in the treatment of cancers. Inhibition of the enzyme cyclooxygenase (COX) with celecoxib had a significantly suppressive effect on tumor growth, angiogenesis, and metastasis in a variety of tumors. The aim of this study was to elucidate the antiglioma effect of combined treatment with IFN-beta and celecoxib in U87 glioma model. METHODS: The in vitro effects of IFN-beta (50-1,000 IU/mL) and celecoxib (50-250 micrometer) alone or combination of both on the proliferation and apoptosis of U87 cells were tested using MTT assay, FACS analysis and DNA condensation. To determine the in vivo effect, nude mice bearing intracerebral U87 xenograft inoculation were treated with IFN-beta intraperitoneally (2x10(5) IU/day for 15 days), celecoxib orally (5, 10 mg/kg) or their combination. RESULTS: IFN-beta or celecoxib showed an inhibitory effect on the proliferation of U87 cells. When U87 cells were treated with IFN-beta and celecoxib combination, it seemed that IFN-beta interrupted the antiproliferative and apoptotic activity of celecoxib. No additive effect was observed on the survival of the tumor bearing mice by the combination of IFN-beta and celecoxib. CONCLUSION: These results suggest that IFN-beta seems to inhibit the antiglioma effect of celecoxib, therefore combination of IFN-beta and celecoxib may be undesirable in the treatment of glioma.

Physical properties of different self-adhesive resin cements and their shear bond strength on lithium disilicate ceramic and dentin / 대한치과보존학회지

The purpose of this study was to evaluate the physical properties of different self-adhesive resin cements and their shear bond strength on dentin and lithium disilicate ceramic and compare these result with that of conventional resin cement. For this study, four self-adhesive resin cements (Rely-X Unicem, Embrace Wetbond, Mexcem, BisCem), one conventional resin cement (Rely-X ARC) and one restorative resin composite (Z-350) were used. In order to evaluate the physical properties, compressive strength, diametral tensile strength and flexural strength were measured. To evaluate the shear bond strength on dentin, each cement was adhered to buccal dentinal surface of extracted human lower molars. Dentin bonding agent was applied after acid etching for groups of Rely-X ARC and Z-350. In order to evaluate the shear bond strength on ceramic, lithium disilicate glass ceramic (IPS Empress 2) disks were prepared. Only Rely-X ARC and Z-350 groups were pretreated with hydrofluoric acid and silane. And then each resin cement was adhered to ceramic surface in 2 mm diameter. Physical properties and shear bond strengths were measured using a universal testing machine. Results were as follows 1. BisCem showed the lowest compressive strength, diametral tensile strength and flexural strength. (P<0.05) 2. Self-adhesive resin cements showed significantly lower shear bond strength on the dentin and lithium disilicate ceramic than Rely-X ARC and Z-350 (P<0.05) In conclusion, self-adhesive resin cements represent the lower physical properties and shear bond strength than a conventional resin cement.

Microleakage of resilon: Effects of several self-etching primer / 대한치과보존학회지

The purpose of this study was to compare the apical microleakage in root canal filled with Resilon by several self-etching primers and methacrylate-based root canal sealer. Seventy single-rooted human teeth were used in this study. The canals were instrumented by a crown-down manner with Gate-Glidden drills and .04 Taper Profile to ISO #40. The teeth were randomly divided into four experimental groups of 15 teeth each according to root canal filling material and self-etching primers and two control groups (positive and negative) of 5 teeth each as follows: group 1 - gutta percha and AH26(R) sealer; group 2 - Resilon, RealSeal(TM) primer and RealSeal(TM) sealer; group 3 - Resilon, Clearfil SE Bond(R) primer and RealSeal(TM) sealer group 4 - Resilon, AdheSe(R) primer and RealSeal(TM) sealer. Apical leakage was measured by a maximum length of linear dye penetration of roots sectioned longitudinally by diamond disk. Statistical analysis was performed using the One-way ANOVA followed by Scheffe's test. There were no statistical differences in the mean apical dye penetration among the groups 2, 3 and 4 of self-etching primers. And group 1, 2 and 3 had also no statistical difference in apical dye penetration. But, there was statistical difference between group 1 and 4 (p < 0.05). The group 1 showed the least dye penetration. According to the results of this study, Resilon with self-etching primer was not sealed root canal better than gutta precha with AH26(R) at sealing root canals. And there was no significant difference in apical leakage among the three self-etching primers.

Microleakage of resilon by methacrylate-based sealer and self-adhesive resin cement / 대한치과보존학회지

The purpose of this study was to compare the apical microleakage in root canal filled with Resilon by methacrylate-based root canal sealer or 2 different self-adhesive resin cements. Seventy single-rooted extracted human teeth were sectioned at the CEJ perpendicular to the long axis of the roots with diamond disk. Canal preparation was performed with crown-down technique using Profile NiTi rotary instruments and GG drill. Each canal was prepared to ISO size 40, .04 taper and 1 mm short from the apex. The prepared roots were randomly divided into 4 experimental groups of 15 roots each and 5 roots each for positive and negative control group. The root canals were filled by lateral condensation as follows. Group 1: Guttapercha with AH-26, Group 2: Resilon with RealSeal primer & sealer, Group 3: Resilon with Rely-X Unicem, Group 4: Resilon with BisCem. After stored in 37degrees C, 100% humidity chamber for 7 days, the roots were coated with 2 layers of nail varnish except apical 3 mm. The roots were then immersed in 1% methylene blue dye for 7 days. Apical microleakage was measured by a maximum length of linear dye penetration after roots were separated longitudinally. One way ANOVA and Scheffe's post-hoc test were performed for statistical analysis. Group 1 showed the least apical leakage and there was no statistical significance between Group 2, 3, 4. According to the results, the self adhesive resin cement is possible to use as sealer instead of primer & sealant when root canal filled by Resilon.

Glucose Transporter-1 Expression in Squamous Cell Carcinoma of the Tongue / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Tumor cells are known to express hypoxia-related proteins such as glucose transporter-1 (Glut-1). These hypoxia-induced changes may allow tumor cells to survive under sustained hypoxic microenvironments, and the surviving tumor cell under hypoxia may develop a more aggressive phenotype and so result in a poor prognosis. MATERIALS AND METHODS: The Glut-1 expression was analyzed by immunohistochemistry, and its association with the prognosis was assessed in 60 patients with squamous cell carcinoma of the tongue. RESULTS: The Glut-1 expression was diffuse with a membranous pattern, and the median percentage of Glut-1 positive tumor cells was 60% (range: 0.0~90.0%). A high Glut-1 expression (the percentage of positive tumor cells > or = the median value, 60%) was associated with the location of primary lesion, lymph node metastasis status and disease stage (p<0.05). The expression of Glut-1 was correlated with the Ki-67 expression (r=0.406, p=0.001). Microvessel density, as represented by CD31 staining, was also correlated with the Glut-1 expression although its significance is weak (r=0.267, p=0.039). On the univariate analysis, the group with a high Glut-1 expression showed poorer overall survival than the group with a low Glut-1 expression (p<0.05). However, the Glut-1 expression failed to show any independent prognostic significance on the multivariate analysis. CONCLUSION: The expression of Glut-1 may be useful for predicting the prognosis and determining the treatment strategy for the management of squamous cell carcinoma of the tongue.

Lifetime and fracture patterns of NiTi rotary files in molars / 대한치과보존학회지

Intracanal separation of the rotary files is a serious concern in modern endodontic practice. The objective of this study was to compare the life span and fracture patterns of three NiTi rotary files in molar teeth. Mesiobuccal roots of upper molar (n = 150) and mesial roots of lower molar (n = 150) were divided into three groups and each group was prepared with Profile, ProTaper, and K3 respectively. Every file was used until separation and/or deterioration of the cutting blade was happened, and then the number of canals to separation and/or unwinding were recorded. Radiographs and Scanning electon microscope (SEM) photographs were taken to evaluate the patterns of separation. The results were as follows : 1. There were no significant differences in numbers of canals to separation and/or unwinding among the groups. 2. Comparing between flaring files, K3 showed significant lower numbers of canals to separation and/or unwinding (p < 0.05), and there was no significant difference between shaping files 3. Separations of instruments were occurred at the midpoint of curvatures within the canals. 4. In SEM observations, ductile fractures were seen in most of cases, characterized by shallow dimples. Additional researches is needed to provide a new guideline that informs the appropriate number of times to use NiTi files.

A new post removal technique using ATD tugging device / 대한치과보존학회지

It is common for clinicians to encounter endodontically treated teeth that contain posts within their roots. If endodontic treatment is failed, these posts must be removed to facilitate successful nonsurgical retreatment. There have been many techniques such as ultrasonic instrument, Ruddle post removal system, Eggler post remover and Masserann kit developed to facilitate removal of posts from the root canal space. But these methods may be disadvantageous because long length of time required for post removal and fracture of post or teeth. In now days new post removal technique using ATD automatic bridge remover was introduced. Advantages of this method are simple and short time consuming compare to others. This article served as a successful case report of post removal using ATD automatic bridge remover.

The influence of different access cavity designs on the fracture strength in endodontically treated mandibular anterior teeth / 대한치과보존학회지

Straight access cavity design allows the operator to locate all canals, helps in proper cleaning and shaping, ultimately facilitates the obturation of the canal system. However, change in the fracture strength according to the access cavity designs was not clearly demonstrated yet. The purpose of this study was to determine the influence of different access cavity designs on the fracture strength in endodontically treated mandibular anterior teeth. Recently extracted mandibular anterior teeth that have no caries, cervical abrasion, and fracture were divided into three groups (Group 1 : conventional lingual access cavity, Group 2 : straight access cavity, Group 3 : extended straight access cavity) according to the cavity designs. After conventional endodontic treatment, cavities were filled with resin core material. Compressive loads parallel to the long axis of the teeth were applied at a crosshead speed of 2mm/min until the fracture occurred. The fracture strength analyzed with ANOVA and the Scheffe test at the 95% confidence level. The results of this study were as follows : 1. The mean fracture strength decrease in following sequence Group 1 (558.90 +/- 77.40 N), Group 2 (494.07 +/- 123.98 N) and Group 3 (267.33 +/- 27.02 N). 2. There was significant difference between Group 3 and other groups (P = 0.00). Considering advantage of direct access to apical third and results of this study, straight access cavity is recommended for access cavity form of the mandibular anterior teeth.

Polymerization ability of several light curing sources on composite resin / 대한치과보존학회지

The purpose of this study is to evaluate the polymerization ability of three different light sources by microhardness test. Stainless steel molds of 1, 2, 3, 4 and 5 mm in thickness of 7 mm in diameter were prepared. The hybrid composite Z100 was packed into the hole of the mold and curing light was activated for designated time. Three different light sources, conventional halogen, light emitting diode, and plasma arc, were used for curing of composite. Two different curing times applied; one is to follow the manufacturer's recommendation and the other is to extend the curing time of LED and plasma arc for balancing the light energy with halogen. Immediately after curing, the Vickers hardness was measured at the bottom of specimen. The results were as follows. 1. The composite cured with LED showed equal to higher microhardnesss than halogen. 2. The composite was cured with plasma arc by manufacturer's recommendation showed lowest microhardness at all thickness. However, when curing time was extended, microhardness was higher than the others. In conclusion, this study suggested that plasma arc needs properly extended curing time.

The postnatal outcome and prognostic cut-off value of fetal pyelectasia / 대한산부인과학회잡지

OBJECTIVE: The purpose of our study was to evaluate the postnatal outcome of fetal pyelectasia and to assess the cut-off value for prediction of renal pathologic processes and surgical intervention. MATERIALS AND METHODS: Seventy-seven cases of pyelectasia were identified during the study period (1996 through 2000). Fetuses with antero-posterior pelvic diameter (APPD) >or=7 mm after 28 weeks were included. Postnatal evaluation included renal sonogram, voiding cystourethrogram, and renal flow and function studies. RESULTS: Renal pathologic processes after birth were found in 38 of 77 cases (49%). Ureteropelvic junction obstruction (19 cases, 50%) was the most common, followed by 4 cases of duplicated kidney, 3 cases of ureterovesical junction obstruction, 2 cases of primary vesicoureteral reflux, dysplastic kidney, extrarenal pelvis respectively and 1 case of ureterocele. Surgical intervention was performed in 21 cases (55%); pyeloplasty (13), nephrectomy (including partial) (3), transurethral incision of ureterocele (2), uretero- ureterostomy (1), uretero-cystostomy (2). Using cut-off value derived from receiver operating characteristic (ROC) curve, renal APPD >or=10.5 mm, >or=13.6 mm after 28 weeks gestation could predict the fetuses who would have renal pathologic processes and need surgical intervention, with sensitivity and specificity of 77.5%, 79.4% and 90.5%, 89.3%, respectively. CONCLUSION: It is possible to predict the fetuses who would require appropriate urologic evaluation and surgical intervention after birth, with determining the renal pelvic diameter in the third trimester of pregnancy.

Effects of Somatostatin Analogue Pretreatment on Ovarian Response to Ovulation Induction in Patients with Polycystic Ovarian Syndrome / 대한산부인과학회잡지

OBJECTIVE: To determine whether the somatostain analogue, octreotide, pretreatment before ovulation induction with human menopausal gonadotropin (hMG) affects ovarian response, and ovulation induction outcome in infertile patients with polycystic ovarian syndrome (PCOS) resistant to clomiphene citrate (CC) METHODS: From November 1998 to June 1999, 30 infertile patients with PCOS unresponsive to CC were randomly allocated either octreotide pretreatment (treatment group) (n = 15) or hMG alone (control group) (n = 15) groups. In the treatment group, 100 g of octreotide were administered daily for 7 days after progesterone injection for withdrawal bleeding, and then hMG was administered for ovulation induction. RESULTS: There were no differences in the total number of hMG ampules required and the duration of hMG administration between the two groups. The number of follicles of 10-14 mm diameter on the day of hCG injection was significantly less in the treatment group than that in the control group (4.3 +/- 2.5 vs. 9.6 +/- 4.4, p < 0.001). The serum estradiol (E2) level on the day of hCG injection was significantly lower in the treatment group, with 1579.2 +/- 421.0 pg/ml compared with 2120.3 +/- 512.7 pg/ml in the control group (p < 0.001). The hematocrit level on the day of hCG injection was also significantly lower in the treatment group than that in the control group (36.9 +/- 2.1% vs. 40.8 +/- 2.9%, p < 0.05). The incidence of severe ovarian hyperstimulation syndrome (OHSS) seemed to be lower in the treatment group, but the difference did not achieve significance (6.7% vs 20.0%). CONCLUSION: This study suggests that octreotide pretreatment before ovulation induction could improve hormonal milieu compared to hMG alone, and therefore may be effective in ovulation induction for patients with PCOS resistant to CC.

Prenatal sonographic findings of Trisomy 18 : review of 23 cases / 대한산부인과학회잡지

No abstract available.

A Case of Werniche's Encephalopathy in Hyperemesis Grevidarum / 대한주산의학회잡지

Werniche's encephalopathy is clinically characterized by the acute onset of global confusion, ataxia, gaze paresis, and nystagmus. It result from a deficiency in thiamine, an essential coenzyme in intermediate carbohydrate metabolism. The prompt use of thiamine prevents progression of the disease and reverses those lesions that have not yet progressed to the point of fixed structural change. We experienced a case of Wemiches encephalopathy associated with hyperemesis gravidarum, which happens to the patient who are injected only dextrose without thiamine. Therefore, we emphasize the need of thiamine replacement in hyperemesis gravidarum.