• Korean Journal of Microbiology
• /
• v.55 no.2
• /
• pp.87-102
• /
• 2019

Most chronic wounds persist in the inflammatory phase during wound healing due to the biofilm. Biofilms are resistant to antibiotics, weakening penetration, resistance to biocides and weakening local immune responses. The biofilm is firmly attached to the surrounding tissues and is very difficult to remove. Therefore, strategies to remove hard biofilms without damaging surrounding tissue are very important. One of possible strategies is dispersal. So many studies have been done to develop new strategies using dispersal mechanisms. In this review paper, especially chemotaxis, phage therapy, polysaccharides, various enzymes (glycosidases, proteases, and deoxyribonucleases), surfactants, dispersion signals, autoinducers, inhibitors were introduced. Combination therapies with other therapies such as antibiotic therapy were also introduced. It is expected that the possibility of treatment of chronic wound infection using the knowledge of the biofilm dispersal mechanisms presented in this paper will be higher.

• Radiation Oncology Journal
• /
• v.14 no.2
• /
• pp.105-113
• /
• 1996

Purpose : To improve treatment modality and results by analysis of clinical characteristics, local control, survival and recurrence rate in limited stage small cell lung cancer. Materials and Methods : patients with limited stage small cell lung cancer were treated with combined radiation and chemotherapy from Feb. 1986 to Dec. 1992 at the National Medical Center We followed up on 21 patients ($81\%$), who were mostly irradiated with 4,000-5.000cGy ($75\%$ of all Patients) in the results by the analysis retrospectively. Survival rate was evaluated by the Kaplan-Meier method Results : Mean survival of irradiated patients with limited small cell lung cancer was 12 months. 1-rear and 2-rear survival rate were $65.3\%$ and $15.4\%$ Tumor response rate and median survival after combined chemotherapy and irradiation were the following: $50\%$ and 15 months of complete response, and $23\%$ and 11 months of partial response respectively. Response rates by radiation dose were $66\%$ for below 4,000cGy $69\%$ for between 4,000-5,000cGy and $86\%$ for above 5,000cGy. 21 of all patients showed treatment failure($81\%$) which as appeared 9 of local failure.9 of distant failure and 3 of local and distant failure. Conclusion : Local response rate after induction chemotherapy alone in limited stage of small cell lung cancer was $54\%$. Furthermore it was increased to $73\%$ after adding of radiation. We have to increase radiation dose above 5,000cGy and need to try new effective chemotherapy agents for the improvement of local control and survival rate and also will try concurrent chemoradiotherapy in near time.

• Clinical and Experimental Pediatrics
• /
• v.48 no.2
• /
• pp.178-185
• /
• 2005

Purpose : The purpose of this study was to evaluate the outcome of children with juvenile myelomonocytic leukemia(JMML) treated with allogeneic hematopoietic stem cell transplantation(allo-HSCT). Methods : Eleven JMML patients aged 8-39 months underwent allo-HSCT. The sources of grafts were unrelated donors(n=7), HLA-matched siblings(n=3) and an HLA 1-antigen mismatched familial donor. All patients had received chemotherapy ${\pm}13$-cis-retinoic acid(CRA) before transplant, and CRA was used, posttransplant, in six patients. Results : Only three patients were in complete remission(CR) at the time of transplantation. Initial chimeric status revealed complete donor chimerism(CC) in five patients, mixed chimerism(MC) in five and autologous recovery(AR) in one. One patient with MC having persistent splenomegaly eventually turned to CC and CR after rapid tapering of cyclosporine, combined with daily use of CRA. An AR case relapsed shortly after transplant but was rescued with second, unrelated cord blood transplantation. Ultimately, six patients are alive, event-free, with a median follow-up of 15.5 months posttransplant. All three deaths occurred in patients who failed to achieve CC, leading to disease progression. Conclusion : We suggest that graft-versus-leukemia effect play an important role and CRA a possible role in posttransplant leukemic involution in JMML. In patients whose leukemic burden is still high with MC after transplant, early tapering of immunosuppressants and introduction of CRA might provide a chance of a cure for some patients.

• Journal of Life Science
• /
• v.26 no.3
• /
• pp.376-386
• /
• 2016

Apoptosis induction has been proposed as an efficient mechanism by which malignant tumor cells can be removed following chemotherapy. The intrinsic mitochondria-dependent apoptotic pathway is frequently implicated in chemotherapy-induced tumor cell apoptosis. Since DNA-damaging agent (DDA)-induced apoptosis is mainly regulated by the tumor suppressor protein p53, and since more than half of clinical cancers possess inactive p53 mutants, microtubule-damaging agents (MDAs), of which apoptotic effect is mainly exerted via p53-independent routes, can be promising choice for cancer chemotherapy. Recently, we found that the apoptotic signaling pathway induced by MDAs (nocodazole, 17α-estradiol, or 2-methoxyestradiol) commonly proceeded through mitotic spindle defect-mediated prometaphase arrest, prolonged Cdk1 activation, and subsequent phosphorylation of Bcl-2, Mcl-1, and Bim in human acute leukemia Jurkat T cells. These microtubule damage-mediated alterations could render the cellular context susceptible to the onset of mitochondria-dependent apoptosis by triggering Bak activation, Δψm loss, and resultant caspase cascade activation. In contrast, when the MDA-induced Bak activation was inhibited by overexpression of anti-apoptotic Bcl-2 family proteins (Bcl-2 or Bcl-xL), the cells in prometaphase arrest failed to induce apoptosis, and instead underwent mitotic slippage and endoreduplication cycle, leading to formation of populations with 8N and 16N DNA content. These data indicate that cellular apoptogenic mechanism is critical for preventing polyploid formation following MDA treatment. Since the formation of polyploid cells, which are genetically unstable, may cause acquisition of therapy resistance and disease relapse, there is a growing interest in developing new combination chemotherapies to prevent polyploidization in tumors after MDA treatment.

• Radiation Oncology Journal
• /
• v.11 no.2
• /
• pp.277-283
• /
• 1993

Background: We peformed a retroslective study in patients with previously untreated advanced (Stage III or IV) laryngeal and hypopharyngeal cancer to compare the results of induction chemotherapy followed by definitive radiation therapy (CT+ RT) with those of conventional laryngectomy and postoperative radiation therapy (OP + RT). Method: Between 1985 and 1990, twenty-four patients were treated with two or three courses of chemotherapy and radiation therapy (66-75 Gy). Twenty-five patients were received laryngectomy and radical neck dissection (except 3 patients) and postoperative radiation therapy (55~64 Gy). Result: After a median fellow-up of 20 months, the actusrial 5-year overall survival rate was $24\%$ (chemotherapy group) and $36\%,$ (op group). (P>0.1). The local control rate was the $65\%,$ (13/20) and $68.2\%,$ (15/22). (p>0.1). The rate of laryngeal preservation was $65\%$ (13/20) in chemotherapy group. Conclusion: Induction chemotherapy and definitive radiation therapy can be effective in preserving the larynx in a high percentage of patients with advanced laryngeal and hypopharyngeal cancer.

• Proceedings of the KOR-BRONCHOESO Conference
• /
• 1981.05a
• /
• pp.39.2-39
• /
• 1981

Recently, there has been many problems in the treatment of OMPC, because of inadequate and abuse of antibiotics, and resistant strain of pathogenic organisms to antibiotics. Authors studied on the culture and sensitivity of otorrhea obtained from 50 patients with OMPC, and evaluated the therapeutic effect of PPA, which is a new derivative of piromidic acid and active against gram (-) bacteria including pseudomonas aeruginosa as well as some gram (+) bacteria. We observed good therapeutic effect on OMPC with pseudomonas and other gram (-) bacteria, and considerable effect on OMPC with gram (+) bacteria.

• Applied Microscopy
• /
• v.40 no.4
• /
• pp.229-235
• /
• 2010

Cervical cancer is associated with low antioxidant status. It has a high prevalence especially amongst woman in Asia and is a leading cause of cancer death. Cancer chemotherapy in vivo improved in cases with high p53 expression in the tumor tissue. The restoration of p53 levels could be a potential strategy to increase chemoresponsiveness. Under circumstances where damage is extensive, p53 plays a direct role in trigering apoptosis. To investigate the effect of curcumin (CMN) as an antioxidant agent on anticancer agent 5-fluorouracil (5FU) induced apoptosis and p53 expression, HPV-18 positive HeLa cells were treated with noncytotoxic amounts of antioxidant. Curcumin induced apoptosis in cervical cancer cells. Morphological hallmarks of apoptosis such as nuclear fragmentation and internucleosomal fragmentation of DNA were observed. CMN caused upregulation of p53 expression, evident from Western blotting data and also increased the susceptibility/apoptosis induced by 5FU. These results show that increasing drug sensitivity of cervical cancer cells by upregulation of p53 using CMN is novel approach and could have a possible therapeutic potential in cervical cancer.

• Radiation Oncology Journal
• /
• v.8 no.2
• /
• pp.219-223
• /
• 1990

This is a retrospective review of 33 patients with large cell lung carcinoma treated at Yonsei University Cancer Center between Jan.1985 and Dec.1989. Of the thirty-three patients, twenty eight were men and five women. Median age was 59 years. Large cell undifferentiated carcinoma was the most common pathologic type, $78.8\%$. Twenty one of thirty three patients had far advanced diseases, stage IIIB-IV at the time of initial diagnosis. Pleural effusion was initially presented in 12 patients, and SVC syndrome appeared in 5 patients. As to location of the primary tumor,19($57.6\%$) appeared in the right lung and 14 ($42.4\%$) in the left. Patients with a centrally located primary tumor mass were nearly the same as those peripherally located (17 vs.16). Fifteen of thirty three patients developed metastasis involving not only bone, brain, the opposite lung, adrenal gland but also soft tissue, skin, pancreas and appendix. Treatment was individualized with 19 treated radically and 14 palliatively. After treatment, only two patients showed a complete response. Long term survival was observed in 4 patients: 1 (24 mo.),2 (41 mo.) and 1 (54 mo.). The overall 2 year survival rate was $14.3\%$ while the median survival time was 6.0 months. Through the analysis of the various factors affecting survival, we observed that pleural effusion-absent group and complete response group had a statistical significant better survival rate (p<0.01).

• Radiation Oncology Journal
• /
• v.7 no.2
• /
• pp.269-277
• /
• 1989

CNS prophylaxis with 18 or 24 Gy cranial irradiation plus intrathecal methotrexate was given to 134 childhood acute lymphoblastic leukemia patients who had got bone marrow remission (M1) after remission induction chemotherapy from August 1979 to December 1986. The rate of initial total CNS relapse was 14.2% (19/134), the rate of isolated CNS relapse was 5.2% (7/134), and the rate of CNS relapse concomittantly combined with bone marrow relapse or testicular relapse was 9% (12/134). Male sex or older age was accociated with higher CNS relapes and the initial peripheral leukocyte count over 50,000/ul had higher relapse rate. Relapse with radiation dose of 18Gy was somewhat lower than that with 24Gy. Within 4 years after CNS prophylaxis occurred 89% of the total CNS relapses, 100% of the isolated CNS relapses, and 83% of the combined CNS relapses. Adjusted to exposed cases to risk of CNS relapse, the total CNS relapse rate was 11.9% during maintenance chemotherapy and 4.9% after maintenance chemotherapy.

• Radiation Oncology Journal
• /
• v.25 no.2
• /
• pp.70-78
• /
• 2007

[ $\underline{Purpose}$ ]: This study analyzed the tumor response, overall survival, progression free survival and related prognostic factors in patients with muscle invasive bladder cancer subjected to bladder preserving treatment. $\underline{Materials\;and\;Methods}$: Between August 1995 and June 2004, 37 patients with muscle invasive (transitional cell carcinoma, clinically stage T2-4) bladder cancer were enrolled for the treatment protocol of bladder preservation. There were 33 males and 4 females, and the median age was 67 years (range $38{\sim}86\;years$). Transurethral resection of the bladder (TURB) was performed in 17 patients who underwent complete resection. The median radiation dose administered was 64.8 Gy (range $55.8{\sim}67\;Gy$). The survival rate was calculated by the Kaplan-Meier method. $\underline{Results}$: An evaluation of the response rate was determined by abdomen-pelvic CT and cystoscopy at three months after radiotherapy. A complete response was seen in 17 patients (46%). The survival rate at three years was 54.7%, with 54 months of median survival (range $3{\sim}91$ months). During the study, 17 patients died and 13 patients had died from bladder cancer. The progression free survival rate at three years was 37.2%. There were 24 patients (64.9%) who had disease recurrence: 16 patients (43.2%) had local recurrence, 6 patients (16.2%) had a distant recurrence, and 2 patients (5.4%) had both a local and distant recurrence. The survival rate (p=0.0009) and progression free survival rates (p=0.001) were statistically significant when compared to the response rate after radiotherapy. $\underline{Conclusion}$: The availability of complete TURB and appropriate chemoradiotherapy were important predictors for bladder preservation and survival.