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ABSTRACT: Previously Langford et al. (2006) developed the pIR203C04 complementation system for Helicobacter pylori, which can be used to complement and restore phenotypic effects in H. pylori mutant, and furthermore they used the complementation system in vivo experiments to animals without altering the ability of strain SSI to colonize mice. In their previous study, the pIR203C04 was able to transform 26695, SSI, J99, and 43504 H. pylori strains by an electroporation method. However, in the present study using a natural transformation the pIR203C04 transformed only 26695 H. pylori but not SSI, J99, 7.13, and G27 H. pylori strains. Since the useful complementation system has a limitation of narrow selection among H. pylori strains, we redesigned the complementation system for the improvement. The same intergenic chromosomal site between hp0203 and hp0204 was utilized for the new complementation system because the insertion at the intergenic site didn't show any polar effects and disruption of other H. pylori genes. The genome sequence analysis showed that the intergenic regions among H. pylori strains may have too low homology to each others to do a homologous recombination. Thus, in addition to the short intergenic region, the fragments of the new complementation system included 3' conserved parts of hp0203 and hp0204 coding regions. Between the fragments there are a chloramphenicol acetyltransferase cassette and multicloning sites, resulting in pKJMSH. DNA fragment of the interest can be cloned into the multicloning sites of pKJMSH and the fragment can be integrated at the intergenic region of H. pylori chromosome by the homologous recombination. Indeed, by the natural transformation, pKJMSH was able to transform all five H. pylori strains of 26695, SSI, J99, 7.13, and G27, which are common for the investigation of molecular pathogenesis. Thus, the new pKJMSH complementation system is applicable to most H. pylori wild-type stains.
The Journal of Microbiology 06/2011; 49(3):481-6. · 1.10 Impact Factor
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ABSTRACT: The use of metformin, an antidiabetic agent, is associated with a reduced risk of fractures in patients with diabetes, suggesting that metformin exerts a beneficial effect on bone tissues. The objective of this study was to assess the effect of metformin on alveolar bone loss in ligature-induced periodontitis and osteoblast, osteoclast, and adipocyte differentiation.
Periodontitis was induced by a ligature around the mandibular first molar of each rat. The rats were divided into two groups: 1) rats with ligature receiving a vehicle (n = 5), and 2) rats with ligature receiving metformin (n = 5). On day 10, after the induction of periodontitis, the alveolar bone volume between the first and second molar was determined via microcomputed tomography. The effect of metformin on osteoblast, osteoclast, and adipocyte differentiation was assessed using MC3T3-E1, cocultures of mouse bone marrow cells and calvaria-derived osteoblasts, and 3T3-L1/C3H10T1/2 cells, respectively. Osteoblast, osteoclast, and adipocyte differentiation was estimated by the degree of mineralization, the formation of tartrate-resistant acid phosphatase-positive multinucleated cells, and the accumulation of triglycerides, respectively.
In ligature-induced periodontitis, the metformin treatment of rats induced a significant reduction in alveolar bone loss compared to vehicle-treated rats. With regard to osteoblast differentiation, metformin augmented the mineralization of MC3T3-E1 cells approximately two-fold over the non-treated cells. However, metformin was shown to exert no effects on osteoclast formation induced by 1,25-dihydroxyvitamin D(3), lipopolysaccharide, and prostaglandin E(2). Moreover, metformin exerted no effect on adipocyte differentiation.
Our findings suggest that metformin may exert a beneficial effect on alveolar bone in periodontitis by increasing osteoblast differentiation.
Journal of Periodontology 03/2010; 81(3):412-9. · 2.60 Impact Factor
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Ji-Yoon Kim,
Yeon-Sil Kim,
Mi-Ryung Ryu, Sung-Whan Kim,
Chul-Seung Kay,
Sei-Chul Yoon,
Woo-Chan Park,
Byung-Joo Song,
Se-Jeong Oh,
Sang-Seol Jung,
Jong-Man Won,
Seung-Nam Kim,
Su-Mi Chung
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ABSTRACT: To evaluate the effect of the simulation method on recurrence among the patients who received radiotherapy after breast-conserving surgery (BCS) for early breast carcinoma.
Between 1995 and 2000, 70 patients with stage I-II breast carcinoma underwent breast-conserving surgery and adjuvant radiotherapy. Twenty nine patients (41.4%) were simulated with the 2D contour-based method (September 1995 to August 1997) and 41 patients (58.6%) were simulated with the 3D CT-based method (September 1997 to February 2000). To analyze the effect of the simulation method, the patient and treatment characteristics were compared.
The characteristics were similar for the patients between the 2D contour-based simulation group and the 3D CT-based simulation group. During a median follow-up period of 75 months, 4 (13.8%) of 29 patients who were treated with 2D simulation and 1 (2.4%) of 41 patients who were treated with 3D simulation group developed treatment failure. The five-year survival rates were 89.2% and 95.1% between the 2D and 3D simulation groups (p=0.196). The five-year disease free survival (DFS) rates were 86.2% and 97.5% between the 2D and 3D simulation groups (p=0.0636). On univariate analysis, age > 40 (p= 0.0226) and the number of dissected axillary lymph node >or= 10 (p=0.0435) were independent predictors of improved 5-year DFS.
Although our data showed marginal significance for the DFS between the two groups, it is insufficient, due to the small number of patients in our study, to prove whether 3D CT-based simulation might improve the DFS and reduce the risk of recurrence when compared with 2D contour-based simulation. Further study is needed with a larger group of patients.
Cancer Research and Treatment 02/2006; 38(1):40-7.
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Ji-Young Jang,
Mi-Ryeong Ryu, Sung-Whan Kim,
Chul-Seung Kay,
Yeon-Sil Kim,
Yoon-Kyeong Oh,
Hyung-Chul Kwon,
Sei-Chul Yoon,
Woo-Chan Park,
Byung-Joo Song,
Se-Jeong Oh,
Sang-Seol Jung,
Jong-Man Won,
Seung-Nam Kim,
Su-Mi Chung
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ABSTRACT: Breast-conserving therapy (BCT) is a practical alternative to mastectomy for treating ductal carcinoma in situ (DCIS). We reviewed our experience for treating patients with DCIS of the breast to evaluate the outcome after performing breast-conserving surgery plus radiotherapy (BCS-RT).
Between January 1983 and December 2002, 25 patients with clinically or mammographically detected DCIS were treated by BCS-RT. One patient was diagnosed with bilateral DCIS. Thirteen cases (50%) had symptomatic lesions at presentation. All 26 cases of 25 patients underwent BCS such as lumpectomy, partial mastectomy or quadrantectomy. All of them received whole breast irradiation to a median dose of 50.4 Gy. Twenty-four cases (92.3%) received a boost to the tumor bed for a median total dose of 59.4 Gy. The median follow up period was 67 months (range: 38 to 149 months).
Two cases (7.7%) experienced ipsilateral breast tumor recurrence (IBTR) after BCS-RT. The histology results at the time of IBTR showed invasive ductal carcinoma (IDC), and the median time to IBTR was 25.5 months. On the univariate analysis, there were no significant factors associated with IBTR in the DCIS patients. The three-year local recurrence free survival rate was 96.0% and the overall survival rate was 96.3%.
After the treatment for DCIS, the IBTR rate in our study was similar to other previous studies. Considering that we included patients who had many symptomatic lesions, close or positive margins and less that complete early data, our result is comparable to the previous studies. We could not find the prognostic significant factors associated with IBTR after BCS-RT. A longer follow up period with more patients would be required to evaluate the role of any predictive factors and to confirm these short-term results.
Cancer Research and Treatment 12/2005; 37(6):344-8.
