• Title/Summary/Keyword: APEX

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Germline Variations of Apurinic/Apyrimidinic Endonuclease 1 (APEX1) Detected in Female Breast Cancer Patients

  • Ali, Kashif;Mahjabeen, Ishrat;Sabir, Maimoona;Baig, Ruqia Mehmood;Zafeer, Maryam;Faheem, Muhammad;Kayani, Mahmood Akhtar
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.18
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    • pp.7589-7595
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    • 2014
  • Apurinic/apyrimidinic endonuclease 1 (APEX1) is a multifunctional protein which plays a central role in the BER pathway. APEX1 gene being highly polymorphic in cancer patients and has been indicated to have a contributive role in Apurinic/apyrimidinic (AP) site accumulation in DNA and consequently an increased risk of cancer development. In this case-control study, all exons of the APEX1 gene and its exon/intron boundaries were amplified in 530 breast cancer patients and 395 matched healthy controls and then analyzed by single-stranded conformational polymorphism followed by sequencing. Sequence analysis revealed fourteen heterozygous mutations, seven 5'UTR, one 3'UTR, two intronic and four missense. Among identified mutations one 5'UTR (rs41561214), one 3'UTR (rs17112002) and one missense mutation (Ser129Arg, Mahjabeen et al., 2013) had already been reported while the remaining eleven mutations. Six novel mutations (g.20923366T>G, g.20923435G>A, g.20923462G>A, g.20923516G>A, 20923539G>A, g.20923529C>T) were observed in 5'UTR region, two (g.20923585T>G, g.20923589T>G) in intron1 and three missense (Glu101Lys, Ala121Pro, Ser123Trp) in exon 4. Frequencues of 5'UTR mutations; g.20923366T>G, g.20923435G>A and 3'UTR (rs17112002) were calculated as 0.13, 0.1 and 0.1 respectively. Whereas, the frequency of missense mutations Glu101Lys, Ser123Trp and Ser129Arg was calculated as 0.05. A significant association was observed between APEX1 mutations and increased breast cancer by ~9 fold (OR=8.68, 95%CI=2.64 to 28.5) with g.20923435G>A (5'UTR), ~13 fold (OR= 12.6, 95%CI=3.01 to 53.0) with g.20923539G>A (5'UTR) and~5 fold increase with three missense mutations [Glu101Lys (OR=4.82, 95%CI=1.97 to 11.80), Ser123Trp (OR=4.62, 95%CI=1.7 to 12.19), Ser129Arg (OR=4.86, 95%CI=1.43 to 16.53)]. The incidence of observed mutations was found higher in patients with family history and with early menopause. In conclusion, our study demonstrates a significant association between germ line APEX1 mutations and breast cancer patients in the Pakistani population.

In vitro comparison of measurement accuracy In pre-enlarged and enlarged canals with four apex locators (근관 성형 전후의 네 가지 전자근관장측정기의 측정 정확성의 비교)

  • Sung, Sang-Yup;Park, Jeong-Kil;Hur, Bock;Kim, Hyeon-Cheol
    • Restorative Dentistry and Endodontics
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    • v.31 no.5
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    • pp.371-377
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    • 2006
  • The purposes of this study were to assess the accuracy of measurements in pre-enlarged canals with small instruments and to compare the accuracies, in enlarged canal, with small size instruments and instruments that match the actual canal diameter using Root ZX, Bingo1020, SmarPex, and e-Magic Finder. Ten extracted teeth were embedded in an alginate model made for testing apex locators. A size 10 file was placed into the root canal until the tip of the file reached the plane of the major diameter of the foramen under a dental operating microscope at the 25 x magnification. The measurement was done with digital caliper and defined as actual length. Electronic length measurement with a size 10 file in pre-enlarged canal was done by reading the index indicating Apex of each device to gain a definite value After completion of canal enlargement to a size 45 file, each difference between actual length and electric measurement value with a size 10 and 40 files in enlarged canal was recorded as L10 and L40. The one-way ANOVA and Scheffe's multiple range tests were computed for analyze the differences among the four apex locators in the same group. The Student's t-test between L10 and L40 of each locator was done. The accuracies of electronic measurements were significantly different among the 4 devices. The file size made no difference on the accuracy of electronic measurement in enlarged canal with same device. The e-Magic Finder was the most accurate device among the 4 apex locators used in this study.

THE SEALING ABILITY OF OBTURATION TECHNIQUES IN OPEN APEX (개방 근첨 치아의 근관 충전방법에 따른 치근단 폐쇄효과에 관한 연구)

  • So, Hyun;Choi, Ho-Young;Choi, Kyung-Kyu;Choi, Gi-Woon
    • Restorative Dentistry and Endodontics
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    • v.25 no.3
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    • pp.435-445
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    • 2000
  • The purpose of this study was to compare the leakage of four different obturation techniques in conjunction with immediate apical barrier of ${\beta}$-tricalcium phosphate(TCP) in teeth with open apex. Eighty single-rooted human premolar teeth were prepared and sectioned horizontally, so maximum diameter in apex was 4mm. Apical defects that were similar to open apex, were created with #1/2 round bur and SF104R bur. The apical foramen were opened to a size 80 file extended 3mm beyond the apex. The teeth were placed into the oasis block soaked saline to simulate periapical tissue often associated with pulpless teeth and received apical barriers consisting of TCP followed by obturation using lateral condensation technique, vertical condensation technique, continuous wave technique and thermoplasticized gutta-percha injection technique. Two unobturated teeth served as positive and negative controls. Teeth were immersed in resorcinol-formaldehyde resin for S days at $4^{\circ}C$, and the resin was allowed to polymerize completely for 4 days at room temperature. Teeth were then sectioned horizontally at 1.5mm(level 1), 2.5mm(level 2) and 3.5mm(level 3) from the apex, and examined under a stereomicroscope at ${\times}40$ magnification. The photographs were taken at ${\times}40$ magnification of the filling in each level and scanned. The leakage length in tooth/resin interface was measured at each of the three levels. Each ratio of leakage was obtained by calculating the ratio of the leakage length of canal wall infiltrated with resin to the total length of the canal and was analyzed statistically(One-way ANOVA and Scheffe test). The result were as follows : 1. At the level 1, there was the least leakage in the thermoplasticized gutta-percha injection technique group(group 4), but there was statistically significant(p<0.05). 2. At the level 2, there was the least leakage in the thermoplasticized gutta-percha injection technique group(group 4), and the most leakage in the continuous wave technique group(group 3). There was statistically significant difference between the thermoplasticized gutta-percha injection technique group and the continuous wave technique group(p<0.05). 3. At the level 3, there was the least leakage in the thermoplasticized gutta-percha injection technique group(group 4), but there were no statistically significant differences between other groups(p>0.05). These results suggest that thermoplasticized gutta-percha injection technique which had 1mm apical gutta-percha matrix after the formation of TCP apical barrier, can demonstrate favorable apical sealing.

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Automated external defibrillator electrode pad placement by the general public and health-care providers : A manikin study (일반인 및 의료종사자들의 자동제세동기를 이용한 제세동에서 전극부착 위치에 관한 연구: 마네킨을 이용한 연구)

  • Park, Si-Eun
    • The Korean Journal of Emergency Medical Services
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    • v.20 no.1
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    • pp.83-94
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    • 2016
  • Purpose: This study aimed to assess defibrillator pad positioning by the general public and healthcare providers during basic life support (BLS) renewal education (RE). Methods: A total 130 subjects performed defibrillation using an automated external defibrillator (AED) equipped with electrode pads developed by the researchers and male resuscitation manikins, in order to assess electrode pad placement (EPP) before BLS RE. Subjects included 54 Healthcare providers (HP) and 76 members of the general public (GP). Results: The apex EPP was positioned in the risk area (RA), more than 5 cm distant from the area recommended, by 63.2% of the GP (n = 48). The apex EPP was positioned in the RA by 44.4% of the HP (n = 23). The distance from the apex (GP $5.27{\pm}2.21cm$, HP $4.18{\pm}1.71cm$) was statistically significant, using Student's t-test. Conclusion: For both GP and HP, apex EPP was significantly in error. Thus, to prevent defibrillation failures, EPP education and practice for GP and HP in all BLS education programs should be improved, and incorrect Korean cardiopulmonary resuscitation guidelines and related literature should be revised and corrected.

Analysis on the corneal thickness and anterior chamber depth of the Keratoconus using Pentacam

  • Kim, Douk-Hoon;Sapkota, Kishor
    • Journal of Korean Clinical Health Science
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    • v.6 no.1
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    • pp.1089-1096
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    • 2018
  • Purpose: To investigate the corneal thickness and anterior chamber depth (ACD) of eyes with Keratoconus in the Korean population with the Pentacam. Methods: The subjects consisted of 84 eyes from Keratoconic adults aged 7-59 years during 2010. The thinnest area, apex zone, and pupil centre of the corneal thickness were measured using the Pentacam pachymetry. ACD value was also measured with Pentacam. Results: There was a statistically significant relationship between thickness of the cornea at the apex area and the pupil centre (p=0.0001). However, there was no statistical difference (p>0.5) in the mean thickness of thinnest area, apex zone, pupil centre of cornea between right eye and left eye. Also, correlation between ACD and corneal thickness in all subjects had no statistical differences (p>0.05) in all subjects. Conclusion: These results suggested that the regional thickness of cornea and ACD with Pentacam can provide correct and useful diagnostic information of the morphology of Keratoconus for the RGP contact lens and diagnosis of abnormal corneal refraction surgery.

A Study of Automatic detection for the Lung Boundary using Lung Apex Region Matching of Chest X-Ray Image (흉부 방사선 영상의 정점영역 매칭을 통한 허파영역 자동검출에 관한 연구)

  • Kim, Sang-jin;Kim, Yong-Man;Lee, Myoung-Ho
    • Journal of Biomedical Engineering Research
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    • v.11 no.2
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    • pp.217-226
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    • 1990
  • This paper presents a new algorithm that extracted lung region in X-ray and enhanced the region. With a lung region that was extracted by histogram threshold value, it was diffi cult to detect perfect lung boundary. Therefore we presented perfect lung boundary detection method using apex detection and apex region restoration. Also, by applying modified equalization algorithm and presented function to inside of lung region, we want to give help to automatic diagnosis In X-ray chest image. Presented main line trace algorithm gave good result in detection of lung boundary And, as apex detection method using lung row and column gray level average value found more correct place of lung than the rpethod of prior algorithm, we succeeded perfect lung region detection, Also, presented function that had lung region's gray level distribution characteristic was very effective to image enhancement.

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Development of Frequency Dependent Type Apex-Locator Improvementation by Auto-calibration Using Impedance Difference (주파수 의존형 전자근관장측정기 개발 및 임피던스차를 이용한 자동보정에 의한 성능향상)

  • Nam, K.C.;Kim, S.C.;Kim, D.W.;Lee, S.J.
    • Proceedings of the KOSOMBE Conference
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    • v.1997 no.11
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    • pp.399-402
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    • 1997
  • It is important to find a accurate root canal length or successful endodontic therapy. By X-ray method takes a long time and difficult in a curved canal. After developed electronic apex locator has allowed to measure the root canal length with easy, in a short time also in a curved canal. But most electronic apex locators have the disadvantage which is too short reading or sometimes the measurement itself becomes impossible if there are electrolytes in the canal. To overcome this drawback, impedance ratio method has been developed. In this study, we have developed frequency dependent electronic apex locator to minimize the interference of electrolytes. And based on that also some error in clinic use, we added the other method. Difference of two signals which are used in calculation of impedance ratio was can be represent the status of root canal fluid. As a result, using impedance ratio method and auto-calibration by voltage difference method can reduce the measurement error.

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A survey on working length determination of endodontic treatment (근관치료의 근관장 측정에 관한 연구: 근관치료학 전공 교수 설문)

  • Ahn, Hye-ra;Seo, Min-Seock
    • The Journal of the Korean dental association
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    • v.55 no.1
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    • pp.42-52
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    • 2017
  • The purpose of this study is to evaluate the preferred method of root canal length determination and the apical limit for canal instrumentation among endodontic teachers of dental school. A questionnaire on the preferred method of root canal length determination and the apical limit for canal instrumentation was designed and distributed to endodontic teachers of various dental schools. The response rate was 90%. The most preferred method of root canal length determination was Electronic apex locator (EAL)(89%). The most favoured apical limit for canal instrumentation was 0.5 to 1.0 mm short of the radiographic apex(78%). The most preferred method of using EAL was that the working length is taken at 'APEX' mark and then distracted 0.5mm from that length.(41%). When there is no agreement between radiographic measurement and EAL measurement, 74% of respondents chose the length of EAL measurement. The majority of endodontic teachers from Korean dental schools preferred EAL to radiograph method in determining root canal length.

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DEVELOPMENT OF NEW FREQUENCY-DEPENDENT TYPE APEX LOCTOR ; VOLTAGE DIFFERENCE COMPENSATING TYPE (주파수의존형 전자근관장측정기의 개발과 정확도에 관한 연구 ; 전압차 자동보정형)

  • Lee, Seung-Jong;Kim, Deok-Won;Nam, Ki-Chang
    • Restorative Dentistry and Endodontics
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    • v.22 no.2
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    • pp.809-819
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    • 1997
  • The purpose of this study was to develop an accurate frequency-dependent type apex locator. To compensate the impedence differences of different canal contents, voltage differences were pre-measured and stored for saline, HOsb1/$2O_2$ and NaOCl. The circuit was adjusted to recognize the different voltages of each solution, thereby the machine could automatically compensate the voltage differences. In the process of this study, the following informations were observed. 1. Most stable apical reading was obtained at 500Hz and 10kHz. 2. There were no differences in accuracy among three different frequency types, sign wave, triangular wave and rectangular wave(p>0.05). 3. Before the compensation of voltage differences, saline, H2O2 and NaOCl showed different readings at the apex even with the frequency-type (p<0.05). 4. After compensating the voltage difference, the accuracy was enhanced from + 0.42 to +0.32 in H2O2(p<0.05), from -0.34 to -0.12 in NaOCl(p<0.05).

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A RADIOGRAPHIC STUDY OF MENTAL FORAMEN IN INTRAORAL RADIOGRAPHS (구내방사선사진상의 이공에 관한 연구)

  • Sohn Jeong-Ick;Choi Karp-Shik
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.25 no.2
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    • pp.501-511
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    • 1995
  • The purpose of this study was to evaluate the position and shape of mental foramen in periapical radiographs. For this study, periapical radiographs of premolar areas were obtained from the 200 adults. Accordingly, the positional and shape changes of mental foramen were evaluated. The authors obtained radiographs according to changes in radiation beam direction in periapical radiographs of premolar areas, and then evaluated the positional and shape changes of mental foramen. The following results were obtained: 1. Shapes of mental foramen were observed elliptical(34.3%), round or oval(28.0%), unidentified(25.5%) and diffuse(12.2%) type in descending order of frequency. 2. Horizontal positions of mental foramen were most frequently observed at the 2nd premolar area(55.3%), the area between the 1st premolar and 2nd premolar(39.6%), the area between the 2nd premolar and 1st molar(3.4%), the 1st premolar area(1.0%), the area between the canine and 1st premolar(0.7%) in descending order of frequency. 3. Vertical positions of mental foramen were most frequently observed at the inferior to apex(67.1%), and at apex(24.8%), overlap with apex(6.4%), superior to apex(1.7%) in descending order of frequency. 4. Shapes of mental foramen were more obviously observed at the upward 10° positioned periapical radiographs. And according to the changes of horizontal and vertical position, they were observed similar to normally positioned periapical radiographs.

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