• Title/Summary/Keyword: Residual survival function

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Effect of Omeprazole on Membrane P-Type ATPase and Peptide Transport in Helicobacter pylori

  • KI, MI-RAN;SOON-KYU YUN;SE-YOUNG HWANG
    • Journal of Microbiology and Biotechnology
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    • v.9 no.3
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    • pp.235-242
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    • 1999
  • We investigated the growth-inhibitory mechanism of Helicobacter pylori by omeprazole (OMP) and its activated sulfenamide (OAS). Using dithiothreitol (DTT) and 5,5'-dithio-bis[2-nitrobenzoic acid] (DTNB; Ellman's reagent), we first determined the relationship between the binding capacity of these compounds to H. pylori membrane and its significance to membrane P-type ATPase activity. After incubation of the intact H. pylori cells with either OMP or OAS, the residual quantity of free SH-groups on the cell membrane was measured, and, the resulting values were plotted as a function of time. From this experiment, we found that there was a considerable difference in the membrane-binding rates between OMP and OAS. At neutral pH, the disulfide bond formation on H. pylori membrane was completed within 2 min of incubation of the intact cells with OAS. By OMP, however, it was gradually formed, exceeding 10 min of incubation for completion, whereby, the extent of P-type ATPase inhibition appeared to be proportional to the disulfide forming rate. From this data, it was suggested that the disulfide formation might directly affect enzyme activity. Since OMP per se cannot yield a disulfide bond with cysteine, it is predicted that the enzyme inactivation must be caused by the OAS form. Accordingly, we postulated that, under the neutral pH, OMP could be converted to OAS in the course of transport. By extrapolating the inhibitory slopes, we could evaluate K₁ values, relating to their minimal inhibitory concentrations (MICs) for H. pylori growth. In these MIC ranges, H. pylori uptake or vesicular export of nutrients such as peptides were totally prohibited, but their effect in Escherichia coli were negligible. From these observations, we strongly suggest that the P-type ATPase activity is essential for the survival of H. pylori cells in particular.

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Efficacy of Mitral Valve Surgery in Moderate Ischemic Mitral Regurgitation (MR) (중등도의 허혈성 승모판막 폐쇄부전증 환자에서 승모판막 수술의 유용성)

  • Jung Sung Ho;Lee Jae Won;Choi Jun Young
    • Journal of Chest Surgery
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    • v.38 no.5 s.250
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    • pp.357-365
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    • 2005
  • Background: Patients with mitral regurgitation (MR) in the setting of coronary artery disease have a dismal long-term prognosis whether treated medically or surgically. Moreover, the optimal management of moderate ischemic MR at the time of coronary artery bypass grafting (CABG) remains the subjects of controversy. Thus, the present retrospective study was undertaken to determine whether mitral valve surgery for moderate ischemic MR at the time of CABG would be preferable to CABG alone in terms of clinical outcome. Material and Method: Between January 1997 and December 2003, 34 patients with moderate (Gr 3/4) ischemic MR underwent CABG alone (Group I, n=23) or CABG plus mitral valve surgery (Group II, n=11). Operative mortality, long-term survival and echocardiographic parameters were used to evaluate the efficacy of mitral valve surgery in patients with moderate ischemic MR. The mean follow-up durations of each group were $69.3\pm4.3$ months and $53.1\pm4.9$ months respectively. Result: There was no hospital mortality in both groups. There was one case of late mortality in Group I. The mean number of bypass graft was similar ($3.8\pm1.2\;vs\;3.7\pm1.3$ respectively). Cardiopulmonary bypass time was longer in group II (p=0.014). In group II, all of the patients received mitral annuloplasty using ring. On immediate postoperative echo-cardiogram, mitral regurgitation was reduced more in group II (p=0.002). Echocardiogram performed at last follow-up state showed no difference except the grade of MR between the two groups. Actuarial survival of both groups at 5 years was similar ($95.5\%\;vs\;100\%$, p=0.48). Conclusion: This study shows that in selected patients with moderate ischemic MR, CABG without mitral valve surgery might be sufficient. However, patients with low EF and NYHA functional class pre-operatively had tendency of significant residual MR, so mitral valve surgery should be necessary in these patients, and moreover, MR severity and left ventricle volume decreased more in mitral valve surgery group. Therefore, more large-scale studies are necessary to determine these effects on the ventricular function and long-term survival.

Long-term Results of Surgical Treatment of Craniopharyngioma : Experience with 100 Adult Patients (성인 두개인두종 연속 100예의 장기 치료 성적)

  • Bang, Jae Seung;Jung, Hee-Won;Kim, Dong Gyu;Gwak, Ho-Shin;Paek, Sun Ha;Chung, Young Seob;Hong, Seung-Koan
    • Journal of Korean Neurosurgical Society
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    • v.30 no.4
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    • pp.472-478
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    • 2001
  • Objectives : The authors present a retrospective analysis of 100 consecutive adult patients harboring craniopharyngiomas who underwent microsurgical resection between 1981 and 1999 to assess the long-term outcome of surgical treatment and to determine the most optimal management strategy. Methods : The extent of surgical removal was divided into four categories ; GTR(gross total removal), RSTR(radical subtotal removal), STR(subtotal removal),and PR(partial removal). The median follow-up period was 50 months(4-198). CT scan and/or MR imaging and hormonal status were evaluated to the last follow-up. Results : Visual disturbance was the most common presentation, which was improved in 42 cases and aggravated in 19 cases following the operation. Hypopituitarism was detected in 56 patients preoperatively, 82 during the immediate postoperative period, and 76 at the last follow-up. Improvement of pituitary function was not observed in any of these patients. Twenty of 100 patients showed recurrence at the mean of 27 months(3 to 196). The median progression-free survival(PFS) time of all patients was 145 months and 5-year PFS rate was 74%. Five-year PFS rate of GTR or RSTR group(71%) was significantly higher than that of STR or PR group(30%)(p=0.01). Postoperative radiation therapy significantly prolonged the PFS from 94 months in non-radiation group to 182 months(p=0.002). However, there was no statistical difference in number of patients who required hormonal replacement therapy between radiation and non-radiation group. Conclusion : Visual disturbance can be improved by early diagnosis and surgical decompression. GTR or RSTR in selected patients is considered a proper surgical strategy. Post-operative radiation therapy for residual tumors must be considered, although the ideal timing of radiation therapy is to be determined.

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Comparision of Risk Factors in Lung Cancer Surgery of Above 70-Year Old Patients (70세이상 환자에 대한 폐암 수술의 위험성 비교)

  • 장인석;심영목;김진국;김관민;유정우
    • Journal of Chest Surgery
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    • v.32 no.1
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    • pp.32-37
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    • 1999
  • Background: Early detection and surgical resection offer the most advantage out of all cures for lung cancer. Elderly patients may fail to benefit maximally from these interventions because of their general condition and residual lung function. To study the impact of age on stages, histology, symptoms, and treatments of the patients with non-small cell lung cancer, we undertook a retrospective review. Material and Method : Two hundred eleven patients with non-small cell lung cancer were operated on at Samsung Seoul hospital between October 1994 and June 1997. Patients were arbitrarily arbitrarily by age less than 70 years(176 patients) and 70 years or more(35 patients), and their medical records were reviewed. Result: There were no differences in pathologic staging and diagnosis. But there were differences in surgical methods, complications, and mortality rates between the two groups. There were much more complications in the 70 years or more group(p=0.02). We chose less invasive surgical methods in the 70 years or more group. Conclusion: More complications were experienced in the 70 years or more group. Although thoracic operation imparts the greatest survival advantage, this benefit is diminished in elderly patients because of their high complications and mortality rate. We recommend serious consideration of surgical indications and operative methods.

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The Biological Stability of Immediate Placement of Tapered Implants in Tooth Extraction Sites (발치와에 즉시 식립한 쐐기형 임플란트의 생물학적 안정성에 관한 전향적 연구)

  • Park, Ja-young;Bae, Ahran;Kim, Hyung-Seub;Kwon, Yong-Dae;Lee, Baek-Soo;Kwon, Kung-Rock
    • Journal of Dental Rehabilitation and Applied Science
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    • v.25 no.2
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    • pp.139-155
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    • 2009
  • Objective : To assess the biological stability of immediate transmucosal placement of tapered implants into tooth extraction sockets. Material and methods : Following tooth extraction, tapered implants were immediately placed into the sockets. Teeth with evidence of acute periapical pathology were excluded. After implant placement, sutured allowing a non-submerged, transmucosal healing. Standardized radiographs were obtained every visiting from baseline to 32 weeks after implant placment. Changes in depth of the distance from the implant shoulder (IS) and from the alveolar crest (AC) to the bottom of the defect (BD) were assessed. Results : Thirteen patients (10 males and 3 females) were enrolled and followed. They contributed with 15 tapered implants. extraction iste displayed sufficient residual bone volume to allow primary stability of all implants. The mean surgery time was $41{\pm}10.0$ mins. All implants healed uneventfully yielding a survival rate of 100%. Mean ISQ values were relatively stable. Interproximal crestal bone decreased $1.69{\pm}1.2mm$ (mesial), $1.65{\pm}1.2mm$ (distal) from baseline to 32-week follow-up. No statistically significant changes with respect to FMPS, FMBS, PPD and width of KG were observed. Conclusions: Immediate transmucosal implant placement represented a predictable treatment option for the replacement of teeth lost due to reasons including fractures, endodontic failures and caries.