A new method for rapid screening of bacterial species- or subspecies-specific DNA probes.

A simple assay for the rapid screening of bacterial species- or subspecies-specific DNA probes for the random cloning method is presented, involving the use of genomic DNAs as probes and recombinant plasmid DNAs containing genomic DNA digested with Hin dIII as targets. The optimal amount of target DNAs and the concentration of digoxigenin-labeled genomic DNA probes were 20 ng and 100 ng ml−1 (or 10 ng and 200 ng ml−1), respectively. The method was applied to the development of Fusobacterium nucleatum subspecies-specific probes. Our results showed that four out of 96 probes were F. nucleatum subspecies-specific, which was confirmed by Southern blot analysis. Our results indicate that the new method can be used for the rapid screening of species- or subspecies-specific probes.This work was supported by Grant No. R05-2001-000- 00451-0 (J.-K. Kook) from the Basic Research Program of the Korean Science and Engineering Foundation

한국인의 치주질환 환자의 치은연하치면세균막에서 Prevotella intermedia와 Prevotella nigrescens의 검출율 비교

본 연구의 목적은 한국인의 치주질환 환자의 치은연하치면세균막에서 Prevotella intermedia와 Prevotella nigrescens의 검출율을 비교하기 위하여 시행하였다. 34명의 환자로부터 총 133개의 치은연하치면세균막을 멸균된 paper point를 이용하여 채취하였으며, 이때 건강한 치주조직이 4개, 치은염을 보이는 치주부위가 103개, 치주염을 보이는 부위가 26개였다. 16S 라이보솜 RNA의 염기서열을 바탕으로 제작된 종-특이 프라이머를 이용한 중합효소연쇄반응법으로 P. intermedia와 P. nigrescens를 치면세균막으로부터 존재유무를 확인하였다. 실험 결과 P. intermedia는 P. nigrescens보다 탐침시 출혈을 보이는 환자에서 검출율이 더 큰 것으로 조사되었다. 또한 P. intermedia는 치주낭 깊이가 4mm이상의 부위에서 P. nigrescens보다 상대적으로 높게 검출되었다. 이러한 결과는 P. intermedia가 P. nigrescens보다 치주질환의 진행에 더 연관성이 높다는 것을 간접적으로 시사한다.This study was supported by a grant of Ministry of Health & Welfare, Republic of Korea(03-PJ1-PG1-CH08-0001)

Multiplex PCR using conserved and species-specific 16S rDNA primers for simultaneous detection of Fu

this study was undertaken to develop PCR primers for the simultaneous detection of Fusobacterium nucleatum and Actinobacillus actinomyceltemcomitans, using two species-specific reverse primers in combination with a single conserved forward primer. These primers target the variable and conserved regions of the 16S rDNA. The primer specificity was tested against (i) four F. nucleatum and three A. actinomycetemcomitans strains and (ii) seven representatives of the different species of oral bacteria. The primer sensitivity was determined by testing serial dilutions of the purified genomic DNA of F. nucleatum and A. actinomycetemcomitans. The data indicate that species-specific amplicons could be obtained for all the F. nucleatum and A. actinomycetemcomitans strains tested, which were not found in the seven other species. The multiplex PCR could detect as little as 4 fg of chromosomal DNA of F. nucleatum and A. actinomycetemcomitans simultaneously. These findings suggest that these PCR primers are highly sensitive and are suitable for applications in epidemiological studies, diagnosis, and monitoring F. nucleatum and A. actinomycetemcomitans after the treatment of periodontitis

Development of PAL-XFEL undulator system

Pohang Accelerator Laboratory (PAL) have developed a 0.1 nm SASE based FEL based on 10 GeV S-band linear accelerator named PAL-XFEL. At the first stage, PAL-XFEL needs two undulator lines for photon source. The hard X-ray undulator line requires 20 units of 5 m long hybrid-type conventional planar undulator and soft X-ray line requires 7 units of 5 m long hybrid type planar undulators. PAL have developed undulator magnetic structure based on EU-XFEL concepts. In this report, the impact of the background field, alignment issues, the results of pole height tuning, and final magnetic measurement results are summarized.111sciescopuskc

Optimal proteinuria target for renoprotection in patients with IgA nephropathy.

BACKGROUND: Proteinuria is a target for renoprotection in kidney diseases. However, optimal level of proteinuria reduction in IgA nephropathy (IgAN) is unknown. METHODS: We conducted a retrospective observational study in 500 patients with biopsy-proven IgAN. Time-averaged proteinuria (TA-P) was calculated as the mean of every 6 month period of measurements of spot urine protein-to-creatinine ratio. The study endpoints were a 50% decline in estimated glomerular filtration rate (eGFR), onset of end-stage renal disease (ESRD), and slope of eGFR. RESULTS: During a median follow-up duration of 65 (12-154) months, a 50% decline in eGFR occurred in 1 (0.8%) patient with TA-P of <0.3 g/g compared to 6 (2.7%) patients with TA-P of 0.3-0.99 g/g (hazard ratio, 2.82; P = 0.35). Risk of reaching a 50% decline in eGFR markedly increased in patients with TA-P of 1.0-2.99 g/g (P = 0.002) and those with TA-P≥3.0 g/g (P<0.001). ESRD did not occur in patients with TA-P<1.0 g/g compared to 26 (20.0%) and 8 (57.1%) patients with TA-P of 1.0-2.99 and ≥3.0 g/g, respectively. Kidney function of these two groups deteriorated faster than those with TA-P<1.0 g/g (P<0.001). However, patients with TA-P of 0.3-0.99 g/g had a greater decline of eGFR than patients with TA-P<0.3 g/g (-0.41±1.68 vs. -0.73±2.82 ml/min/1.73 m2/year, P = 0.03). CONCLUSION: In this study, patients with TA-P<1.0 g/g show favorable outcomes. However, given the faster eGFR decline in patients with TA-P of 0.3-0.99 g/g than in patients with TA-P<0.3 g/g, the ultimate optimal goal of proteinuria reduction can be lowered in the management of IgAN