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Tobacco smoking is considered one of the most significant environmental risk factors for destructive periodontal disease.
The effect of smoking on periodontopathic microbiota has not yet been elucidated, as previous studies failed to identify a
concrete relationship between periodontopathic microorganisms and smoking. However, it is likely that smoking, as an environmental
stress factor, may affect the behavior of dental plaque microorganisms, ultimately leading to alteration of the host-parasite
interaction. The goal of this study was to examine the effect of nicotine, a major component of tobacco, on the growth and
protein expression of the crucial periodontal pathogen Porphyromonas gingivalis. The growth of P. gingivalis 381 was measured after bacterial cells were cultivated in liquid broth containing various nicotine concentrations. First,
P. gingivalis cells were allowed to grow in the presence of a single dose of nicotine (the single exposure protocol) at 0, 1, 2, 4, and
8 mg/L, respectively. Second, P. gingivalis cells were exposed to five consecutive doses of nicotine (the multiple exposure protocol) at 0, 1, 2, and 4 mg/L, respectively.
Bacterial growth was measured by optical density and protein expression was analyzed by SDS-PAGE and 2-D gel electrophoresis.
In the single nicotine exposure protocol, it was observed that the growth of P. gingivalis 381 was inhibited by nicotine in a dose-dependent manner. In the multiple nicotine exposure protocol, the growth rate of
P. gingivalis increased with each subsequent nicotine exposure, even though bacterial growth was also inhibited in a dose dependent fashion.
SDS-PAGE and 2-D gel electrophoresis analyses revealed a minor change in the pattern of protein expression, showing differences
in proteins with low molecular weights (around 20 kDa) on exposure to nicotine. The results of this study suggest that nicotine
exerts an inhibitory effect on the growth of P. gingivalis, and has a potential to modulate protein expression in P. gingivalis. 相似文献
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Yoo JY Kim HC Zhu W Kim SM Sabet M Handfield M Hillman J Progulske-Fox A Lee SW 《FEMS microbiology letters》2007,275(2):344-352
Molecular pathogenesis of Tannerella forsythia, a putative periodontal pathogen, has not yet been adequately elucidated due to limited information on its virulence factors. Here, identification of in vivo expressed antigens of T. forsythia is reported using in vivo-induced antigen technology (IVIAT). Among 13 000 recombinant clones screened, 16 positive clones were identified that reacted reproducibly with sera obtained from patients with periodontal disease. DNA sequences from 12 of these in vivo-induced genes were determined. IVIAT-identified protein antigens of T. forsythia include: BspA, a well-defined virulence factor of T. forsythia; enzymes involved in housekeeping functions (tRNA synthetases, glycine hydroxymethyltransferase, and glucoside glucohydrolase); enzymes implicated in tissue destruction (dipeptidyl peptidase IV); a DNA mismatch repair protein; and putative outer membrane proteins of unknown function. The in vivo gene expression of these IVIAT-identified antigens was confirmed by a quantitative real-time PCR analysis. This is, to the best of the authors' knowledge, the first report using IVIAT in T. forsythia. It is anticipated that detailed analysis of the in vivo-induced genes identified by IVIAT in this study will lead to a better understanding of the molecular mechanisms mediating periodontal infection by T. forsythia. 相似文献
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Chul Kim Seung Bin Baek Do Hun Kim Sung Chul Lim Hyeong Ju Lee Hee Cheon Lee 《Journal of peptide science》2009,15(5):353-358
The temperature dependence of the partition of a neuropeptide, substance P (SP), in isotropic (q = 0.5) bicelles was investigated by using pulsed field gradient NMR diffusion technique. The partition coefficient decreases as the temperature is increased from 295 to 325 K, indicating a favorable (negative) enthalpy change upon partitioning of the peptide. Thermodynamic analysis of the data shows that the partitioning of SP at 300 K is driven by the enthalpic term (ΔH) with the value of ? 4.03 kcal mol?1, while it is opposed by the entropic term (?TΔS) by approximately 1.28 kcal mol?1 with a small negative change in heat capacity (ΔCp). The enthalpy‐driven process for the partition of SP in bicelles is the same as in dodecylphosphocholine (DPC) micelles, however, the negative entropy change in bicelles of flat bilayer surface is in sharp contrast with the positive entropy change in DPC micelles of highly curved surface, indicating that the curvature of the membrane surface might play a significant role in the partitioning of peptides. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
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Juyeong Oh Seok Hwan Kim Yu Jeong Kim Hyunho Lee Joon Hyong Cho Young Ho Cho Chul-Ki Kim Taik Jin Lee Seok Lee Ki Ho Park Hyeong Gon Yu Hyuk-jae Lee Seong Chan Jun Jae Hun Kim 《PloS one》2014,9(5)
Differential interference contrast microscopy is designed to image unstained and transparent specimens by enhancing the contrast resulting from the Nomarski prism-effected optical path difference. Retinitis pigmentosa, one of the most common inherited retinal diseases, is characterized by progressive loss of photoreceptors. In this study, Differential interference contrast microscopy was evaluated as a new and simple application for observation of the retinal photoreceptor layer and retinitis pigmentosa diagnostics and monitoring. Retinal tissues of Royal College of Surgeons rats and retinal-degeneration mice, both well-established animal models for the disease, were prepared as flatmounts and histological sections representing different elapsed times since the occurrence of the disease. Under the microscopy, the retinal flatmounts showed that the mosaic pattern of the photoreceptor layer was irregular and partly collapsed at the early stage of retinitis pigmentosa, and, by the advanced stage, amorphous. The histological sections, similarly, showed thinning of the photoreceptor layer at the early stage and loss of the outer nuclear layer by the advanced stage. To count and compare the number of photoreceptors in the normal and early-retinitis pigmentosa-stage tissues, an automated cell-counting program designed with MATLAB, a numerical computing language, using a morphological reconstruction method, was applied to the differential interference contrast microscopic images. The number of cells significantly decreased, on average, from 282 to 143 cells for the Royal College of Surgeons rats and from 255 to 170 for the retinal-degeneration mouse. We successfully demonstrated the potential of the differential interference contrast microscopy technique’s application to the diagnosis and monitoring of RP. 相似文献
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Yeon Kyung Chi Ji Won Han Hyeon Jeong Jae Young Park Tae Hui Kim Jung Jae Lee Seok Bum Lee Joon Hyuk Park Jong Chul Yoon Jeong Lan Kim Seung-Ho Ryu Jin Hyeong Jhoo Dong Young Lee Ki Woong Kim 《PloS one》2014,9(1)
We developed a weighted composite score of the categorical verbal fluency test (CVFT) that can more easily and widely screen Alzheimer''s disease (AD) than the mini-mental status examination (MMSE). We administered the CVFT using animal category and MMSE to 423 community-dwelling mild probable AD patients and their age- and gender-matched cognitively normal controls. To enhance the diagnostic accuracy for AD of the CVFT, we obtained a weighted composite score from subindex scores of the CVFT using a logistic regression model: logit (case) = 1.160+0.474× gender +0.003× age +0.226× education level – 0.089× first-half score – 0.516× switching score -0.303× clustering score +0.534× perseveration score. The area under the receiver operating curve (AUC) for AD of this composite score AD was 0.903 (95% CI = 0.883 – 0.923), and was larger than that of the age-, gender- and education-adjusted total score of the CVFT (p<0.001). In 100 bootstrapped re-samples, the composite score consistently showed better diagnostic accuracy, sensitivity and specificity for AD than the total score. Although AUC for AD of the CVFT composite score was slightly smaller than that of the MMSE (0.930, p = 0.006), the CVFT composite score may be a good alternative to the MMSE for screening AD since it is much briefer, cheaper, and more easily applicable over phone or internet than the MMSE. 相似文献
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Do-Soon Park Sung-Jin Na Shin Hyeong Cho Kyung Ja June Young-Chae Cho Young-Ha Lee 《The Korean journal of parasitology》2014,52(4):391-397
We evaluated the status of Clonorchis sinensis infection and potential risk factors among residents of riverside areas (Geumgang) in Muju-gun, Jeollabuk-do (Province), Korea. From January to February 2010, a total of 349 (171 males, 178 females) stool samples were collected and examined by the formalin-ether concentration technique. Also, village residents were interviewed using questionnaires to obtain information about C. sinensis infection-related risk factors. Overall egg-positive rate of C. sinensis was 13.2%. Egg-positive rates were significantly higher in males, farmers, and residents who had lived there more than 20 years, and in residents who had eaten raw freshwater fish than in opposite groups, respectively. However, there was no significant difference between age groups, education levels, cigarette smoking, alcohol drinking, health status, past history of infection, and experience of clonorchiasis medication and examination. Logistic regression analysis was performed to determine risk factors for clonorchiasis. On univariate analysis, the odds ratios for males, farmers, those who had lived there more than 20 years, and who had eaten raw freshwater fish were 2.41, 4.44, 3.16, and 4.88 times higher than those of the opposites, respectively. On multivariate analysis, the odds ratio of residents who had eaten raw freshwater fish was 3.2-fold higher than that of those who had not. These results indicate that residents living in Muju-gun, along the Geum River, Korea, have relatively high C. sinensis egg-positive rates, and the habit of eating raw freshwater fish was the major factor for the maintenance of clonorchiasis. 相似文献
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Jeeun Kang Woong Youn Chung Sang-Wook Kang Hyeong Ju Kwon Jaeheung Yoo Eun-Kyung Kim Jin Ho Chang Tai-kyong Song Sohee Lee Jin Young Kwak 《PloS one》2014,9(11)