• Title/Summary/Keyword: Survival function

Search Result 846, Processing Time 0.026 seconds

An Eclogical Study on the Aquatic Animals in Jungrang Stream of Seoul (중랑천의 수서동물에 관한 생태학적 연구)

  • 배경석;박종태;조기찬;길혜경;신재영
    • Journal of Environmental Health Sciences
    • /
    • v.23 no.2
    • /
    • pp.89-97
    • /
    • 1997
  • Most of urban streams in Korea have been changed channel forms and suffered from direct inflow of domestic sewage, etc. Therefore, maintenance of structure and function of those ecosystem are hard. The present study was carried out to examine the life survival maintenance ability of the stream by community analysis of aquatic animals in typical urban stream (Jungrang stream) in Seoul. The aquatic animals were composed of 31 species, 18 families, 8 orders, 5 classes in 4 phyla. Seasonal species number showed big fluctuation between 8 species in Winter and 24 species in Autumn. Major dominant species in Jungrang stream were Tubificidae sp.1, Chironomidae sp.1, Chironomidae sp.2 and Physa acuta, and above endurance species for water pollution occupied very high dominance indices. But, Cercion hieroglyphicum, Ischnura asiatica, Rantra chinensis, Herochares striatus, Agabus japonicus in benthic macroinvertebrates of a few individuals are appeared. Also, fry of Carassius auratus and Silurus asotus in fish are occurred. Therefore, we can be inferred on posibility of growth and spawning of above species in the stream. Jungrang stream has a small quantity of natural riffle areas, ponds and watergrass areas by channel form of water course. Aquatic animals in Jungrang stream has been suffered by reduction of self-purification reaction ability and have mass production of attached algae on the stream bed. For analysis of fluctuation of life survival maintenance ability in Jungrang stream, long-term survey is needed.

  • PDF

Estimation methods and interpretation of competing risk regression models (경쟁 위험 회귀 모형의 이해와 추정 방법)

  • Kim, Mijeong
    • The Korean Journal of Applied Statistics
    • /
    • v.29 no.7
    • /
    • pp.1231-1246
    • /
    • 2016
  • Cause-specific hazard model (Prentice et al., 1978) and subdistribution hazard model (Fine and Gray, 1999) are mostly used for the right censored survival data with competing risks. Some other models for survival data with competing risks have been subsequently introduced; however, those models have not been popularly used because the models cannot provide reliable statistical estimation methods or those are overly difficult to compute. We introduce simple and reliable competing risk regression models which have been recently proposed as well as compare their methodologies. We show how to use SAS and R for the data with competing risks. In addition, we analyze survival data with two competing risks using five different models.

Multi-walled Carbon Nanotubes Affect the Morphology and Membrane Potential of Mitochondria in HeLa Cell

  • Lee, Wonwoo;Cho, Hyo Min;Oh, Chung Seok;Kim, Eun Hae;Sun, Woong
    • Applied Microscopy
    • /
    • v.44 no.2
    • /
    • pp.68-73
    • /
    • 2014
  • With wide use of nano-materials, it is increasingly important to address their potential toxicity to mammalian cells. However, toxic effects of these materials have been mainly assessed by the cell survival assays. Considering that mitochondrial morphology and quality are highly sensitive to the condition of the cells, and the impairment of mitochondrial function greatly affect the survival of cells, here we tested the impact of multi-walled carbon nanotubes (MWNT) on the survival, mitochondrial morphology, and their membrane potential in HeLa cells. Interestingly, although MWNT did not induce cell death until 24 hours as assessed by pyknotic cell assay, mitochondrial length was elongated and the mitochondrial membrane potential was significantly reduced by exposure of HeLa cells to MWNT. These results suggest that MWNT exposure is potentially harmful to the cell, and the mechanism how MWNT alters mitochondrial quality should be further explored to assess the safety of MWNT use.

A Statistical Methodology for Evaluating the Residual Life of Water Mains (상수관로의 잔존수명 평가를 위한 통계적 방법론)

  • Park, Suwan;Choi, Chang Log;Kim, Jeong Hyun;Bae, Cheol Ho
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.23 no.3
    • /
    • pp.305-313
    • /
    • 2009
  • This paper provides a method for evaluating a residual life of water mains using a proportional hazard model(PHM). The survival time of individual pipe is defined as the elapsed time since installation until a break rate of individual pipe exceeds the Threshold Break Rate. A break rate of an individual pipe is estimated by using the General Pipe Break Model(GPBM). In order to use the GPBM effectively, improvement of the GPBM is presented in this paper by utilizing additional break data that is the cumulative number of pipe break of 0 for the time of installation and adjusting a value of weighting factor(WF). The residual lives and hazard ratios of the case study pipes of which the cumulative number of pipe breaks is more than one is estimated by using the estimated survival function. It is found that the average residual lives of the steel and cast iron pipes are about 25.1 and 21 years, respectively. The hazard rate of the cast iron pipes is found to be higher than the steel pipes until 20 years since installation. However, the hazard rate of the cast iron pipes become lower than the hazard rates of the steel pipes after 20 years since installation.

Experimental Study of Homotransplantation of Lung in Dogs (폐장이식에 관한 실험적 연구)

  • 김진식
    • Journal of Chest Surgery
    • /
    • v.2 no.1
    • /
    • pp.25-40
    • /
    • 1969
  • Lung homotransplantation was performed in 15 pairs of dog. Methotrexate and R.E.S. blocking were used to prolong the survival time. Details of handling the transplant, operative technique and management of the recipient were discussed and following results were obtained: 1]. 7 dogs out of 15 dogs of homotransplantation of lung were survived beyond 3 days. In the group of dogs treated with methotrexate, the average survival was 8.5 days, and in the group of dogs treated with R.E.S. blocking, the average survial was 9.7 days with longest survival of 17 days. 2]. The causes of immediate postoperative death in homotransplantation of dogs were lung edema and disruption of bronchial anastomosis. 3]. The main causes of death in successful homotransplantation dogs which were survived beyond 3 days were infection of lung parenchyma and bronchial necrosis rather than the occurence of graft rejection. 4]. Graft rejection was not revealed even after 7 days of operation in the group treated with methotrexate as well as in the group treated with R. E.S. blocking. This finding made it suggest that the R. E.S. blocking may be effective to control the rejection reaction. 5]. Even though the pulmonary function of transplanted lung was revealed the evidence of severe impairment immediate after operation by bronchospirometry, it was increased gradually and 10 days after operation the minute ventilation and oxygen uptake were decreased 8%, 13% respectively less than pre-operative one.

  • PDF

Organ preservation with neoadjuvant chemoradiation in patients with orbit invasive sinonasal cancer otherwise requiring exenteration

  • Amsbaugh, Mark J.;Yusuf, Mehran;Silverman, Craig;Bumpous, Jeffrey;Perez, Cesar A.;Potts, Keven;Tennant, Paul;Redman, Rebecca;Dunlap, Neal
    • Radiation Oncology Journal
    • /
    • v.34 no.3
    • /
    • pp.209-215
    • /
    • 2016
  • Purpose: We sought to determine if organ preservation (OP) with neoadjuvant chemoradiation (CRT) was feasible in patients with sinonasal cancer determined to require exenteration. Materials and Methods: Twenty patients were determined to require exenteration for definitive treatment from 2005 to 2014. Fourteen patients underwent OP and 6 patients received exenteration with adjuvant CRT. Exenteration free survival (EFS), locoregional control (LRC), progression-free survival (PFS), and overall survival (OS) were estimated. Results: Five patients (36%) receiving OP had complete disease response at time of surgery. With a median follow-up of 18.8 months, EFS was 62% at 2 years for patients undergoing OP. At 2 years, there were no significant differences in LRC, PFS or OS (all all p > 0.050) between the groups. Less grade 3 or greater toxicity was seen in patients undergoing OP (p = 0.003). Visual function was preserved in all patients undergoing OP. Conclusion: For patients with sinonasal cancer, OP may avoid exenteration, offering similar disease control and improved toxicity.

Identification and Characterization of Calcineurin Targets in Cryptococcus neoformans

  • Park, Hee-Soo;Heitman, Joseph;Cardenas, Maria E.
    • 한국균학회소식:학술대회논문집
    • /
    • 2016.05a
    • /
    • pp.17-17
    • /
    • 2016
  • Calcineurin governs stress survival, sexual differentiation, and virulence of the human fungal pathogen Cryptococcus neoformans. Herein, we identified and characterized calcineurin substrates in C. neoformans by employing phosphoproteomic $TiO_2$ enrichment and quantitative mass spectrometry. The identified targets include the zinc finger transcription factor Crz1 and proteins whose functions are linked to P-bodies/stress granules (PBs/SGs) and mRNA translation and decay, such as Pbp1 and Puf4. We show that Crz1 is a bona fide calcineurin substrate, and localization and transcriptional activity of Crz1 are controlled by calcineurin. Several of the calcineurin targets localized to PBs/SGs, including Puf4 and Pbp1, and are required for survival at high temperature and for virulence. Genetic epistasis analysis revealed that Crz1 and the novel targets Lhp1, Puf4, and Pbp1 function in a branched calcineurin pathway that orchestrates stress survival and virulence. These findings propose that calcineurin controls thermal stress and virulence at the transcriptional level via Crz1 and post-transcriptionally by regulating target factors involved in mRNA metabolism.

  • PDF

Indirubin-3-monoxime Prevents Tumorigenesis in Breast Cancer through Inhibition of JNK1 Activity

  • Kim, Mi-Yeon;Jo, Eun-Hye;Kim, Yong-Chul;Park, Hee-Sae
    • Biomedical Science Letters
    • /
    • v.27 no.3
    • /
    • pp.134-141
    • /
    • 2021
  • c-Jun N-terminal kinases (JNKs) have a Janus face, regulating both cell apoptosis and survival. The present study focused on understanding the function of JNK in tumor development and the chemoresistance underlying JNK-mediated cancer cell survival. We identified an inhibitor of JNK1, an important regulator of cancer cell survival. Kinase assay data showed that JNK1-dependent c-Jun phosphorylation was inhibited by indirubin derivatives. In particular, indirubin-3-monoxime (I3M) directly inhibited the phosphorylation of c-Jun in vitro, with a half inhibition dose (IC50) of 10 nM. I3M had a significant inhibitory effect on JNK1 activity. Furthermore, we carried out assays to determine the viability, migration, and proliferation of breast cancer cells. Our results demonstrated that cell growth, scratched wound healing, and colony forming abilities were inhibited by the JNK inhibitor SP600125 and I3M. The combination of SP600125 and I3M significantly decreased cancer cell proliferation, compared with either SP600125 or I3M alone. Our studies may provide further support for JNK1-targeting cancer therapy using the indirubin derivative I3M in breast cancer.

Prognosis of Malignant Melanoma on Lower Extremity (하지에 발생한 악성 흑색종의 예후)

  • Kim, Ji Ye;Lee, Won Jai;Lew, Dae Hyun;Rah, Dong Kyun;Tark, Kwan Chul
    • Archives of Plastic Surgery
    • /
    • v.36 no.4
    • /
    • pp.411-416
    • /
    • 2009
  • Purpose: Malignant melanoma is recognized as the most serious skin cancer. We examined anatomical distribution and 5 - year survival rate of each stage of malignant melanoma on lower leg. Methods: We retrospectively analyzed the medical records of 91 patients(46 males and 45 females) with malignant melanoma on lower leg from 1985 to 2008. Age, sex, anatomical distribution and 5 - year survival rates of each stage of malignant melanoma on lower leg were investigated. Also, 5 - year survival rates of each stage and invasion depth of malignant melanoma on heel pad were investigated. Results: On lower leg, most frequently 32 cases(35.1%) occurred on heel pad, 27 cases(29.7%) occurred on dorsum of foot, 18 cases(19.8%) in toe and 14 cases(15.4%) on others in lower leg. We used the excision margin as 3 ~ 5 cm. After wide excision, in stage III, IV, the patients underwent the immunologic / chemo - therapy. The incidences of each stage were 22 cases(24.2%) in stage I, 47(51.6%) in II, 17(18.7%) in III and 5(5.5%) in IV. The 5 - year survival rates of each stage were 85%, 53.2%, 47.1% and 40%. On heel pad, the incidences of each stage were 5 cases(15.6%) in stage I, 19 cases(59.4%) in II, 7 cases(21.9%) in III and 1 case(3.1%) in IV. The 5 - year survival rates of each stage were 80%, 63.2%, 42.9% and 100%. On heel pad, incidence of local recurrence was 2 and 5 - year survival rate of this case was 100%. And systemic recurrence was 9 and 5 - year survival rate of this case was 55.6%. Conclusion: The 5 - year survival rate of malignant melanoma on heel pad was higher than previous study. To maintain the weight - bearing function of foot, we recommend the active reconstructive surgery for heel pad reconstruction after wide excision of heel pad malignant melanoma.

Relationships among Pain, Upper Extremity Function, and Anxiety in the Breast Cancer Survivors (유방암 생존자의 상지기능, 통증 및 불안과의 관계)

  • Lim, Jeong-Sun;Kim, Jong-Im
    • Journal of muscle and joint health
    • /
    • v.19 no.1
    • /
    • pp.37-45
    • /
    • 2012
  • Purpose: This study was to compare pain, upper extremity function, and anxiety among disease characteristics in the breast cancer survivors and to clarify the relationship among these variables. Methods: One hundred twenty two participants with breast cancer survivors over the age of 30 were recruited from a general hospital. Data were collected from November 1 to December 25, 2006 using a structured questionnaire. Results: The mean age was 51.17 and their mean survival period was 38.08 months. The breast cancer survivors who had received radiation therapy reported lower levels of pain and upper extremity function, and higher levels of anxiety than those who had other treatments. Pain and anxiety were positively related, and upper extremity function was negatively related to pain and anxiety. Conclusion: The breast cancer survivors experienced pain, upper extremity function disorder and anxiety. This study indicates that nursing interventions for the breast cancer survivors may be needed to improve upper extremity function, and to reduce pain and anxiety.