Background: In modern society, the use of computers accounts for a large proportion of our daily lives. Although substantial research is being actively conducted on musculoskeletal diseases resulting from computer use, there has been a recent surge in interest in improving the working environment for prevention.
Objects: This study aimed to examine the effects of posture correction feedback (PCF) on changes in neck posture and muscle activation during computer typing.
Methods: The participants performed a computer typing task in two sessions, each lasting 16 minutes. The participant’s dominant side was photographed and analyzed using ImageJ software to verify neck posture. Surface electromyography (EMG) was used to confirm the participant’s cervical erector spinae (CES) and upper trapezius muscle activities. The EMG signal was analyzed using the percentage of reference voluntary contraction and amplitude probability distribution function (APDF). In the second session, visual and auditory feedback for posture correction was provided if the neck was flexed by more than 15° in the initial position during computer typing. A 20-minute rest period was provided between the two sessions.
Results: The neck angle (p = 0.014), CES muscle activity (p = 0.008), and APDF (p = 0.015) showed significant differences depending on the presence of the PCF. Furthermore, significant differences were observed regarding the CES muscle activity (p = 0.001) and APDF (p = 0.002) over time.
Conclusion: Our study showed that the feedback system can correct poor posture and reduces unnecessary muscle activation during computer work. The improved neck posture and reduced CES muscle activity observed in this study suggest that neck pain can be prevented. Based on these results, we suggest that the PCF system can be used to prevent neck pain.
For preliminary molecular typing, PCR-based fingerprinting using random amplified polymorphic DNA (RAPD) is the method of choice. In this study, 14 bacterial strains were isolated from different Korean food sources, identified using 16S rRNA gene sequencing, and characterized through RAPD-PCR. Two PCR primers (239 and KAY3) generated a total of 130 RAPD bands, 14 distinct PCR profiles, 10 polymorphic bands, one monomorphic band, and four unique bands. Dendrogram-based analysis with primer 239 showed that all 14 strains could be divided into seven clades out of which clade VII had the maximum of seven. In contrast, dendrogram analysis with the primer KAY3 divided the 14 L. citreum strains into four clades out of which clade IV consisted of a maximum of 10 strains out of 14. This research identified and characterized bacterial populations associated with different Korean foods. The proposed RAPD-PCR method, based on sequence amplification, could easily identify and discriminate the lactic acid bacteria species at the strain-specific level and could be used as a highly reliable genomic fingerprinting tool.
For preliminary molecular typing, PCR-based fingerprinting using random amplified polymorphic DNA (RAPD) is the method of choice. In this study, 14 bacterial strains were isolated from different Korean food sources, identified using 16S rRNA gene sequencing, and characterized through RAPD-PCR. Two PCR primers (239 and KAY3) generated a total of 130 RAPD bands, 14 distinct PCR profiles, 10 polymorphic bands, one monomorphic band, and four unique bands. Dendrogram-based analysis with primer 239 showed that all 14 strains could be divided into seven clades out of which clade VII had the maximum of seven. In contrast, dendrogram analysis with the primer KAY3 divided the 14 L. citreum strains into four clades out of which clade IV consisted of a maximum of 10 strains out of 14. This research identified and characterized bacterial populations associated with different Korean foods. The proposed RAPD-PCR method, based on sequence amplification, could easily identify and discriminate the lactic acid bacteria species at the strain-specific level and could be used as a highly reliable genomic fingerprinting tool.
Fermented food consists of a variety of lactic acid bacteria (LAB) that are also used in the industry as starter cultures. This genus comprises of different species that find importance as a preservatives in food like meat and sausages. Likewise, Lactobacillus brevis has been recognized as GRAS and is a potential probiotic strain extensively being used on an industrial scale. Since such bacteria are directly related to human health, there has been a need to identify and characterize them on the molecular level. In this study, LAB was identified and characterized from various fermented food samples available in South Korea. Two types to PCR-based molecular typing methods were used to analyze the 13 Lactobacillus brevis isolates, of which one was based on difference in the banding patterns originated on agarose gel and the other was related to the sequence analyses of various housekeeping genes in the particular strain. The former rep-PCR technique used three primers namely, REP, ERIC and (GTG)5 that amplified repetitive sequences in the genome and provided characteristic fingerprint profile for each isolate. This clustered the strains in 3 groups with the help of UPGMA method of clustering distinguishing between closely related strains. However, the latter multilocus sequencing typing (MLST) technique provided definite identification of the strains. A set of 7 housekeeping genes were determined as groEL, gyrB, rpoA, rpoB, pheS, recA and dnaK. These genes were amplified and sequenced and were subjected to comparative analysis. Discrete allelic profiles and 13 sequence types (STs) were resolved and minimum spanning tree (MST) was constructed, revealing the genetic relatedness among the isolates. On comparing the results from both the techniques, MLST proved to generate accurate and precise fingerprints owing to the sequence analysis of conserved genes thus providing a scope for research in the monitoring related species.
The genus Pediococcus belongs to the lactic acid bacteria and includes 15 species which are used in the food industry as both starter and probiotic cultures. The importance of Pediococcus spp. is due to their use as starter cultures in fermented meat as well as to their presence as the natural microbiota in vegetables. The availability of P. pentosaceus in the food industry increases the need for reliable molecular techniques for strain identification. To date, the reliable molecular methods for definite identification at strain level of microorganisms used in food industry has not been developed. Molecular identification based on suitable marker genes could be a promising alternative to conventional molecular typing methods such as ribotyping. In this study, the applicability of seven housekeeping genes gyrB, pyc, pgm, leuS, glnA, and dalR in combination with the pgi gene in multilocus sequence typing of P. pentosaceus was assessed. Sequencing and comparative analysis of sequence data were performed on 6 strains isolated from various vegetables. In addition to 17 sequence types, two new sequence types were identified and these fortified sequence types and seven marker genes allowed for a clear differentiation of the strains analyzed, indicating their applicability in molecular typing.
Thirty-one Campylobacter jejuni isolates (22 from various local sources, 9 from imported chicken meats) were subtyped with PFGE and flaA typing to investigate their genetic relatedness. Based on a 90% similarity criterion, 23 and 21 genotypic patterns were formed by PFGE and flaA typing, respectively. The discriminatory indices for PFGE, flaA typing, and a composite analysis of PFGE and flaA typing were 0.9785, 0.9527, and 0.9871, respectively. Similar patterns in composite analysis were observed between sources (cattle and chicken, and cattle and human), indicating that reservoir animals may have been the source of human campylobacteriosis. Therefore, strict hygiene measures from farm to table should be implemented to prevent diseases due to C. jejuni in humans.
Prolonged sitting can contribute to low back pain. The lumbar taping can be applied to correct the sitting posture. This study aimed to investigate the effect of lumbar taping on lumbar kinematics and the muscle activities of multifidus (MF) and internal oblique in the individuals with nonspecific chronic low back pain (NSCLBP) as they type for 30 minutes. Nineteen subjects with NSCLBP (9 people in non taping group and 10 people in taping group) were recruited. Lumbar taping was applied to the taping group before typing. Both groups started typing in a neutral sitting position with their feet on the floor. The change of posture and S2 posterior tilting (S2P) were measured to investigate kinematic data. Three sensors were attached on T12, L3, and S2 to identify the change of posture. Surface electromyography was used to measure the muscle activities. Palpation meter was used to standardize the angle of pelvic tilt in sagittal plane before typing. All instruments were used to measure each data before and after typing. Independent t-test was used to compare the changing values of lumbar kinematics and muscle activities before and after typing between both groups. The changing values of S2P and change of posture of L3 and S2 were significantly smaller in the taping group compared to the non taping group (p<05). The changing value of muscle activities of MF between before and after typing was significantly smaller in the taping group compared to the non taping group (p<05). In conclusion, the lumbar taping during the 30-minute typing task can be applied to maintain correct sitting posture in the lumbar and pelvis and to maintain activation of MF.
Asymmetric sitting posture may cause asymmetric buttock pressure and unilateral low back pain
(LBP). The purpose of this study was to compare the differences of buttock pressure between both sides, and pelvic angle (sagittal and coronal planes) during typing in a sitting position on a pressure mat (Baltube) in individuals with and without unilateral LBP. Ten subjects with unilateral LBP and ten subjects without unilateral LBP were recruited for this study. Buttock pressure was measured using a pressure mat and pelvic angles were measured using a palpation meter. The subjects performed typing in a sitting posture for 30 minutes. Pressure data were collected and averaged at initial term (from start to first minutes) and final term (last minutes of 30 minutes). Angles of pelvic tilting were measured after 30 minutes typing. Pressure asymmetry values (difference in pressure between both sides) were calculated at the initial and final terms. A two-way analysis of variance was used to compare the differences between the initial and final pressure asymmetry values in subjects with and without unilateral LBP. An independent t-test was applied to compare the pelvic tilt angles between the two groups. To compare the change of pressure from the initial term to the final term between the symptomatic and asymptomatic sides in the unilateral LBP group, a paired t-test was applied. In the unilateral LBP group, the pressure asymmetric value at the final term was significantly greater than that of the initial term (p<.05). The angle of pelvic tilting in coronal plane was significantly greater in the unilateral back pain group compared to the without unilateral LBP group (p<.05), however, there was no significant difference in the angle of pelvic tilting in the sagittal plane between the two groups (p>.05). In the unilateral LBP group, the change of pressure from the initial term to the final term was significantly less in the symptomatic side (-6.90 ㎜Hg) than the asymptomatic side (5.10 ㎜Hg). This asymmetric sitting posture may contribute to unilateral LBP in the sitting position. Further studies are needed to determine if asymmetric weight bearing in sitting causes unilateral LBP or if unilateral back pain causes asymmetric weight bearing, and if the correction of asymmetric weight bearing in sitting can reduce unilateral LBP.
The dental infections have been increased due to the widespread overuse and exposure to antibiotics. One of the well-known pathogens is S. aureus The pathogenic properties of S. aureus is associated with the virulence gene. The objective of this study is to investigate the distribution of virulence gene of S. aureus which may contribute to the prevention and treatment of bacterial infections. 54 strains of S. aureus were separated from saliva taken from 129 outpatients diagnosed with periodontitis from Jun. to Dec., 2010 in Seoul. 44 (46.6%) and 13 (31.7%) strains of them were obtained from 88 and 41 outpatients from the S and E dental clinics, respectively. Then, the distribution of virulence gene and genetic diversity were analyzed with the PCR technique. The result of the S. aureus isolates possessed coagulase gene and showed six polymorphism types 390~470 bp (1.8%), 550~633 bp (3.7%), 630~714 bp (9.3%), 715~795 bp (20.4%), 796~876 bp (40.7%) and 877~957 bp(22.2%) due to variable numbers of tandem repeats present within the gene. In this study it will be anticipated that this study can contribute to establish efficiently the countermeasure about the prevention and treatment of antibiotic bacterial infections.
[Aims] Lentinula edodes (Berk.) Pegler has many commercial strains both morphologically and physiologically similar to each other. At present, detection of polymorphism in rDNA-IGS region (Babasaki, 2006) and/or RAPD marker (Zhang and Molina, 1995) is generally used for strain typing of L. edodes. However, it is rather time-and-cost consuming. Inter-retrotransposon amplified polymorphism (IRAP)-PCR method mainly used for horticultural crops takes less time and lower in cost in strain typing (Kalendar et al, 1999). In this study, we designed IRAP primers for L. edodes and verified their strain typing efficiency. [Method] Thirty three strains were provided for this study. Either fungal cultures on PDA or fungal tissues of fruit bodies were cut into approximately 4 x 4 x 4 mm. Total DNA of each samples were extracted by DNeasy Plant Mini Kit (QIAGEN). For PCR, IRAP primer set and Pfu-X polymerase (greiner) were performed. Based on LTR (Long Terminal Repeat) sequence in L. edodes, we designed one set of primers amplifying the regions between retrotransposons. Ampricons were electrophored for 50 min at 100 V on 1.7 % agarose gel with GelRed (Biotium) and evaluated under UV irradiation. [Results] The products obtained by IRAP-PCR were determined using mini-gel electrophoresis system. The band patterns of IRAP-PCR products differ among strains except the ones having the same parental cultivar. The detected bands were bright and clear without smearing. The IRAP-PCR products of fungal cultures on PDA and correlating fungal tissues of fruit bodies showed the same band pattern, suggesting that the procedure is highly reproducible. Thus, it is considered that IRAP-PCR with short ranged (ca. 1 kb) electrophoresis is a time-efficient and practical strain typing method of L. edodes.
자작나무에서 자라는 버섯에는 차가버섯(Inonotus Obli-quus) 과 나스또야식 뚜르또빅(Fomes fomentarius (Fr.) Gill)과 로쥐느이 뚜르또빅(Phellinus igniarius(L. ex Fr) Quel)의 3종류가 있다. 이 중에서 차가버섯만 약효가 있고 독성이 없음이 알려져 있으나 다른 버섯은 아직 약효나 독성에 대해 확인 된 것이 없다. 차가버섯을 채취하는 사람들이 차가버섯과 함께 다른 버섯들도 같이 채취하여 주생산지인 러시아뿐만 아니라 국내에서 수입한 차가버섯을 구입할 때 다른 버섯이 섞여 있는지 확인하기가 어렵고 품질의 규격기준도 거의 외관에 의존하고 있는 실정이다. 본연구자들은 국내시장에 반입되어 유통 되고 있는 17종의 차가버섯을 수집하여 5.8S 함유 ITS (including ITS1, 5.8S and ITS2)부위를 이용한 PCR 증폭시험방법으로 DNA 염기서열을 비교분석 하였다. 차가버섯 시료의 DNA추출은 Chen 등(1999)이 사용한 LETS 방법 등으로 추출, 정제하여 사용하였다. 시험 결과 17개 샘풀 중 12종은 염기 서열 간 97% 이상 상동성이 매우 높아 차가버섯(약 70%)으로 확인되었고 5종은 PCR 증폭산물이 거의 이루어지지 않는 이종의 버섯으로 확인되었다. 본시험 결과, 시중의 차가버섯 중 일부는 차가버섯이 아니거나 이종의 버섯이 혼입된 채 유통되고 있다는 것을 확인 할 수 있었다. 향후 이와 같은 신속하고 정확한 유전자 감별법은 판별이 어려운 버섯류 품질관리에 유익하게 사용 될 것으로 판단된다.
In order to investigate phenotype and genotype of Salmonella enterica subsp. enterica serovar Enteritidis, Forty-eight S. Enteritidis isolates from diarrhea patients were analysed using antimicrobial resistance typing, Phage typing, and Pulsed field gel electrophoresis in Seoul from 2004 to 2005. All of S. Enteritidis were resistant to streptomycin(SM, 37.5%), ampicillin(AM, 43.8%), t icarcillin(TIC, 43.8%), chloramphenicol(CM, 29.2%), t etracycline(TE, 10 .4%) and nalidixic acid(NA, 18.8%) among 16 antimicrobial drugs. Of 48 S. Enteritidis, 8 isolates(16.7%) were resistant to 1 drug, 3 isolates( 6.3%) to 2 drugs, 1 isolate (2.1%) to 3 drugs and 17 isolates(35.7%) to 4 drugs. The basic pattern of 4 drugs resistance was SM, TIC, TE, and CM but 1 drug resistant isolates represent all nalidixic acid resistance. Among 30 antibiotic r esistant S . Enteritidis, 2 1 isolates(70 %) were phage type 2 1, 8 i solates(26.7%) were phage t ype 2 3 and 1 isolate( 3.3%) was RDNC, respectively. Of the phage types observed, all of phage type 23(8 isolates) were nalidixic acid resistant and phage type 21 were AM-TIC-SM-CM multi-resistance(13 isolates; 43.3%), AM-TIC-SM-TE(4 isolates; 13.3%), AM-TIC-SM(1 isolate; 3.3%), AM-TIC-CM(1 isolate; 3.3%), and AM-TIC(2 isolates; 6.7%) resistance and 1 isolate of RDNC was NA-TE resistance. PFGE divided the isolates into two major clusters, A(n=14) and B(n=14). There were four different resistance profiles with resistance to AM, TIC, SM, TE, NA within PFGE A. Also resistance to AM, TIC, SM, CM was common within PFGE B. The PFGE A strains typed as PT21(n=5), PT23(n=8), and RDNC(n=1), While all the PFGE B strains typed as PT21(n=14). In consequence, there was the highly significant concurrence between resistance typing, phage typing and PFGE.
With the introduction of the video display terminal (VDT), the efficiency and productivity of work has improved. However, VDT syndrome is threatening the health of workers as a side effect of prolonged use of a VDT. Among various VDT syndromes, the musculoskeletal disorder, especially, the cumulative trauma disorder (CTD) is the common research topic related with upper extremities function. The aim of this study was to investigate the effect of the wrist-hand orthosis (WHO) on fatigue in middle deltoid, anterior deltoid, serratus anterior, and upper trapezius during one-hour computer keyboard typing. Twelve healthy subjects participated in this study. Surface electromyography was used to assess the localized muscle fatigue (LMF), and the LMF was calculated at 10 minutes, 20 minutes, 40 minutes, and 60 minutes in each muscle, with and without the WHO. Data were analyzed by paired t-test with a level of significance of .05. The results of this study are as follows: 1) At 10 minutes, the LMF decreased significantly with applied WHO in the middle deltoid, anterior deltoid, and upper trapezius (p=.001, p=.026, p=.019, respectively). 2) As the computer keyboard typing period increased, there were no significant LMF differences, except for the upper trapezius. Therefore, it can be concluded that the WHO can be applied to decrease the LMF for the initial 10 minute period in the middle deltoid, anterior deltoid, and upper trapezius' but that the long term effect of WHO in reducing the LMF was proven only in upper trapezius during continued computer keyboard typing.
To investigate antimicrobial susceptibility and relationships of the multidrug resistance and phage types of 49 Salmonella enterica serovar Typhimurium isolated from diarrhea patients in Seoul between 1999 and 2002, we analyed stranis by serotyping, antimicrobial susceptibility test and phage typing. Out of 2,705 samples examined for the causative agent from diarrhea patients, total of 512 isolates were confirmed to be genus Salmonella. Out of 512 isolates, 49 isolates(9.6%) were identified as S. Typhimurium. All of the S. Typhimurium strains represented 100% susceptibility to ceftriaxone, cefoxitin, amikacin and ciprofloxacin and were over 90% susceptibility to gentamicin, cephalothin and kanamycin, but were resistant to tetracycline(75.5%), streptomycin(59.2%), sulfonamides(55.1%), ticarcillin(36.7%), ampicillin( 28.6%), and chloramphenicol(20.4%). Out of 49 S. Typhimurium, only 3 isolates(20.4%) were resistant to one drug, 6 isolates(12.2%) to two drugs and 12 isolates(24.5%) to 3 drugs, 1 isolate(2.0%) to 4 drugs, 2 isolates (4.1%) to 5 drugs, and 6 isolates(12.2%) to 6 drugs and 5 isolates (10.2%) to 7 drugs. Out of 49 S. Typhimurium, 10 isolates(20.4%) were DT195, 5 isolates(10.2%) were DT193 and DT206, 4 isolates(8.2%) were DT104L, DT146, DT203 and RDNC, respectively. Phage types observed the resistant patterns of more than 6 drugs were DT104L, DT193, DT194, DT195 and DT67, but those of 3 drugs representing S-S3-TE type was DT195.
RAPD 분석은 한 개의 primer를 이용하여 임의의 DNA조각을 증폭하는 것이다. 이 때 만들어지는 여러 형태의 DNA band유형을 이용하여 살모넬라를 분류할 수 있다. 살모넬라를 효과적으로 RAPD typing할 수 있는 sprimer들을 엄선하기 위하여 살모넬라 표준균주 16종을 대상으로 총 20가지 primer들의 RAPD 분리력을 비교하여 보았다. 결과는 재현성이 높았으며 이중 primer A, OPG04, OPG10, OPL-03은 16가지 균 모두를 다른 유형으로 분리하였고 primer OPB-17, OPB-6, OPG08, OPL-02는 15가지 유형으로 분리하였다. 이들은 discrimination index, band의 숫자, band scoring의 난이도 등을 고려해 볼 때 나머지 primer 들에 비해 우수한 분리력을 보였다. 이들 primer들은 장차 살모넬라의 RAPD typing에 이용될 수 있을 것으로 보이며, 현재는 이들을 이용하여 돈육 공장의 오염원 규명을 위한 연구를 수행 중이다.
RAPD 분석은 한 개의 primer를 이용하여 임의의 DNA조각을 증폭하는 것이다. 이때 만들어지는 여러 형태의 DNA pattern을 이용하여 리스테리아 모노사이토제네스를 분류할 수 있다. 리스테리아균들을 효과적으로 RAPD typing 할 수 있는 primer들을 엄선하기 위하여 리스테리아 표준균주 13종을 대상으로 총 31가지 primer들의 RAPD분리력을 비교하여 보았다 결과는 재현성이 높았으며 이중 6가지 primer(primer 6, HLWL74, UBC155, UBC127, Lis5, Lisll)가 discrimination index, band의 숫자, band scoring의 난이도 등을 고려해 볼 때 나머지 primer 들에 비해 우수한 분리력을 보였다. 이들 primer들은 장차 리스테리아의 RAPD typing에 이용될 수 있을 것으로 보이며, 현재는 이들을 이용하여 돈육공장의 오염원 규명을 위한 연구를 수행 중이다
This experiment was carried out to clarify the pedigree identification from blood typing of 301 Hoisteins in National Animal Breeding Institute(N.A.B.I.). Twenty kinds of standard reagent standardized by Insternational Society for Animal Blood Group Research provied from KNC improvement center, N, L, C, F. were used as the reference reagents in this study. The highest frequency of antigenic facfors was obtained from Xin blood typing of 301 Holsteins. The frequency of X was 0.714.In A blood system, four kinds of phenogroups were observed. The gene frequencies of Al and Z' phenogroups were equally 0.027.This frequency was greatly lower than those of breeds of Southern European and Zebu cattle. In B blood Systern, nineteen kinds of blood type were appeared. The appearance frequency of Gx blood type was 0.259, whish was higher than the others. In C blood system, thirty kinds of blood type were observed. The appearance frequency of X blood type was the highest(0.189). In F blood system, three kinds of alleles were detected. The gene frequency of F allele was higher than that of V(0.105). However, the frequency of F allele(0.327) was greatly lower than that of "- /- " allele. In S blood system, twelve kinds of blood type were appeared and showed sirnilar appearance frequencies except " - / - " allele. From the results of the pedigree identification from 8 sires and 28 progenies of them, the accuracy of pedigree identification was 92.9%.ification was 92.9%.