A Model of Survival Times for Predator Populations: The Case of Army Ants

1999 ◽  
Vol 61 (3) ◽  
pp. 469-482 ◽  
Author(s):  
N Britton
Keyword(s):  
Survival Times ◽  
Army Ants

Transition (markov) models for the analysis of survival times in clinical research

1999 ◽  
Vol 28 (1) ◽  
pp. 165-176
Author(s):  
Sati Mazumdar ◽  
Kenneth Liu ◽  
Sang Ahnn ◽  
Patricia R. Houck ◽  
Charles F. Reynolds
Keyword(s):  
Clinical Research ◽  
Markov Models ◽  
Survival Times

Oxygen treatment after perinatal hypoxia-ischemia reduces neuronal damage at short survival times, but worsens injury with long-term survival

2005 ◽  
Vol 25 (1_suppl) ◽  
pp. S444-S444 ◽  
Author(s):  
Kristin M Noppens ◽  
J Regino Perez-Polo ◽  
David K Rassin ◽  
Karin N Westlund ◽  
Roderic Fabian ◽  
...  
Keyword(s):  
Neuronal Damage ◽  
Perinatal Hypoxia ◽  
Survival Times ◽  
Term Survival ◽  
Long Term Survival ◽  
Short Survival ◽  
Oxygen Treatment ◽  
Hypoxia Ischemia

scholarly journals Outcomes Related to Percutaneous Nephrostomies (PCN) in Malignancy-Associated Ureteric Obstruction: A Systematic Review of the Literature

2021 ◽  
Vol 10 (11) ◽  
pp. 2354
Author(s):  
Francesca J. New ◽  
Sally J. Deverill ◽  
Bhaskar K. Somani
Keyword(s):  
Quality Of Life ◽  
Advanced Cancer ◽  
Previous Treatment ◽  
Cochrane Library ◽  
Cancer Type ◽  
Ureteric Obstruction ◽  
Survival Times ◽  
Advanced Malignancies ◽  
The Impact

Background: Malignant ureteric obstruction occurs in a variety of cancers and has been typically associated with a poor prognosis. Percutaneous nephrostomy (PCN) can potentially help increase patient longevity by establishing urinary drainage and treating renal failure. Our aim was to look at the outcomes of PCN in patients with advanced cancer and the impact on the patients’ lifespan and quality of life. Materials and Methods: A literature review was carried out for articles from 2000 to 2020 on PCN in patients with advanced malignancies, using MEDLINE, EMBASE, Scopus, CINAHL, Cochrane Library, clinicaltrials.gov, and Google Scholar. All English-language articles reporting on a minimum of 20 patients who underwent PCN for malignancy-associated ureteric obstruction were included. Results: A total of 21 articles (1674 patients) met the inclusion criteria with a mean of 60.2 years (range: 21–102 years). PCN was performed for ureteric obstruction secondary to urological malignancies (n = −633, 37.8%), gynaecological malignancies (n = 437, 26.1%), colorectal and GI malignancies (n = 216, 12.9%), and other specified malignancies (n = 205, 12.2%). The reported mean survival times varied from 2 to 8.5 months post PCN insertion, with an average survival time of 5.6 months, which depended on the cancer type, stage, and previous treatment. Conclusions: Patients with advanced malignancies who need PCN tend to have a survival rate under 12 months and spend a large proportion of this time in the hospital. Although the advent of newer chemotherapy and immunotherapy options has changed the landscape of managing advanced cancer, decisions on nephrostomy must be balanced with their survival and quality of life, which must be discussed with the patient.

Risk scoring by CHADS2 and CHA2DS2-VASc as predictors for long-term outcomes after surgical ablation for atrial fibrillation

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
D Lauritzen ◽  
H.J Vodstrup ◽  
T.D Christensen ◽  
M Onat ◽  
R Christensen ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Cardiac Surgery ◽  
Isolation Procedure ◽  
Survival Times ◽  
Long Term Outcomes ◽  
Surgical Ablation ◽  
Follow Up Study ◽  
Risk Scoring

Abstract Background Following catheter ablation for atrial fibrillation (AF), CHADS2 and CHA2DS2-VASc have utility in predicting long-term outcomes. However, it is currently unknown if the same holds for patients undergoing surgical ablation. Purpose To determine whether CHADS2 and CHA2DS2-VASc predict long-term outcomes after surgical ablation in concomitance with other cardiac surgery. Methods In this prospective, follow-up study, we included patients who underwent biatrial ablation - or pulmonary vein isolation procedure concomitantly with other cardiac surgery between 2004 and 2018. CHADS2 and CHA2DS2-VASc scores were assessed prior to surgery and categorized in groups as 0–1, 2–4 or ≥5. Outcomes were death, AF, and AF-related death. Follow-up was ended in April 2019. Results A total of 587 patients with a mean age of 68.7±0.4 years were included. Both CHADS2 and CHA2DS2-VASc scores were predictors of survival p=0.005 and p<0.001, respectively (Figure). For CHADS2, mean survival times were 5.9±3.7 years for scores 0–1, 5.0±3.0 years for scores 2–4 and 4.3±2.6 years for scores ≥5. For CHA2DS2-VASc mean survival times were 7.3±4.0 years for scores 0–1, 5.6±2.9 years for scores 2–4 and 4.8±2.1 years for scores ≥5. The incidence of death was 20.1% for CHADS2 0–1, 24.8% for CHADS2 2–4, and 35.3% for CHADS2 ≥5, p=0.186. The incidence of AF was 50.2% for CHADS2 0–1, 47.9% for CHADS2 2–4, and 76.5% for CHADS2 ≥5, p=0.073. The incidence of AF related death was 13.0% for CHADS2 0–1, 16.8% for CHADS2 2–4, and 35.3% for CHADS2 ≥5, p=0.031. The incidence of death was 16.8% for CHA2DS2-VASc 0–1, 26.2% for CHA2DS2-VASc 2–4, and 45.0% for CHA2DS2-VASc ≥5, p=0.001. The incidence of AF was 49.6% for CHA2DS2-VASc 0–1, 52.5% for CHA2DS2-VASc 2–4, and 72.5% for CHA2DS2-VASc ≥5, p=0.035. The incidence of AF related death was 12.2% for CHA2DS2-VASc 0–1, 16.0% for CHA2DS2-VASc 2–4, and 42.5% for CHA2DS2-VASc ≥5, p<0.001. Conclusion Both CHADS2 and CHA2DS2-VASc scores predict long-term outcomes after surgical ablation for AF. However, CHA2DS2-VASc was superior in predicting death, AF, and AF-related death. Survival curves Funding Acknowledgement Type of funding source: None

scholarly journals Common pathways and functional profiles reveal underlying patterns in Breast, Kidney and Lung cancers

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Sergio Romera-Giner ◽  
Zoraida Andreu Martínez ◽  
Francisco García-García ◽  
Marta R. Hidalgo
Keyword(s):  
Molecular Mechanisms ◽  
Machine Learning Techniques ◽  
Alternative Activation ◽  
Survival Times ◽  
Major Health Problem ◽  
Lung Cancers ◽  
Cancer Data ◽  
Cell Functions ◽  
Cancer Pathogenesis ◽  
Tissue Of Origin

Abstract Background Cancer is a major health problem which presents a high heterogeneity. In this work we explore omics data from Breast, Kidney and Lung cancers at different levels as signalling pathways, functions and miRNAs, as part of the CAMDA 2019 Hi-Res Cancer Data Integration Challenge. Our goal is to find common functional patterns which give rise to the generic microenvironment in these cancers and contribute to a better understanding of cancer pathogenesis and a possible clinical translation down further studies. Results After a tumor versus normal tissue comparison of the signaling pathways and cell functions, we found 828 subpathways, 912 Gene Ontology terms and 91 Uniprot keywords commonly significant to the three studied tumors. Such features interestingly show the power to classify tumor samples into subgroups with different survival times, and predict tumor state and tissue of origin through machine learning techniques. We also found cancer-specific alternative activation subpathways, such as the ones activating STAT5A in ErbB signaling pathway. miRNAs evaluation show the role of miRNAs, such as mir-184 and mir-206, as regulators of many cancer pathways and their value in prognoses. Conclusions The study of the common functional and pathway activities of different cancers is an interesting approach to understand molecular mechanisms of the tumoral process regardless of their tissue of origin. The existence of platforms as the CAMDA challenges provide the opportunity to share knowledge and improve future scientific research and clinical practice.

scholarly journals Long-term survival benefit of ramipril in patients with acute myocardial infarction complicated by heart failure

Heart ◽  
2021 ◽  
Vol 107 (5) ◽  
pp. 389-395
Author(s):  
Jianhua Wu ◽  
Alistair S Hall ◽  
Chris P Gale
Keyword(s):  
Myocardial Infarction ◽  
Heart Failure ◽  
Acute Myocardial Infarction ◽  
Life Expectancy ◽  
Survival Benefit ◽  
Ace Inhibition ◽  
Survival Times ◽  
Term Survival ◽  
Long Term Survival

AimsACE inhibition reduces mortality and morbidity in patients with heart failure after acute myocardial infarction (AMI). However, there are limited randomised data about the long-term survival benefits of ACE inhibition in this population.MethodsIn 1993, the Acute Infarction Ramipril Efficacy (AIRE) study randomly allocated patients with AMI and clinical heart failure to ramipril or placebo. The duration of masked trial therapy in the UK cohort (603 patients, mean age=64.7 years, 455 male patients) was 12.4 and 13.4 months for ramipril (n=302) and placebo (n=301), respectively. We estimated life expectancy and extensions of life (difference in median survival times) according to duration of follow-up (range 0–29.6 years).ResultsBy 9 April 2019, death from all causes occurred in 266 (88.4%) patients in placebo arm and 275 (91.1%) patients in ramipril arm. The extension of life between ramipril and placebo groups was 14.5 months (95% CI 13.2 to 15.8). Ramipril increased life expectancy more for patients with than without diabetes (life expectancy difference 32.1 vs 5.0 months), previous AMI (20.1 vs 4.9 months), previous heart failure (19.5 vs 4.9 months), hypertension (16.6 vs 8.3 months), angina (16.2 vs 5.0 months) and age >65 years (11.3 vs 5.7 months). Given potential treatment switching, the true absolute treatment effect could be underestimated by 28%.ConclusionFor patients with clinically defined heart failure following AMI, ramipril results in a sustained survival benefit, and is associated with an extension of life of up to 14.5 months for, on average, 13 months treatment duration.

Effects of covariates on alternating recurrent events in accelerated failure time models

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Moumita Chatterjee ◽  
Sugata Sen Roy
Keyword(s):  
Recurrent Events ◽  
Failure Time ◽  
Likelihood Method ◽  
Model Parameters ◽  
Accelerated Failure Time ◽  
Survival Times ◽  
Copula Functions ◽  
Event Time ◽  
Accelerated Failure Time Models ◽  
Accelerated Failure

AbstractIn this article, we model alternately occurring recurrent events and study the effects of covariates on each of the survival times. This is done through the accelerated failure time models, where we use lagged event times to capture the dependence over both the cycles and the two events. However, since the errors of the two regression models are likely to be correlated, we assume a bivariate error distribution. Since most event time distributions do not readily extend to bivariate forms, we take recourse to copula functions to build up the bivariate distributions from the marginals. The model parameters are then estimated using the maximum likelihood method and the properties of the estimators studied. A data on respiratory disease is used to illustrate the technique. A simulation study is also conducted to check for consistency.

scholarly journals Recent Advances in Nanomedicine for the Diagnosis and Treatment of Prostate Cancer Bone Metastasis

Molecules ◽  
2021 ◽  
Vol 26 (2) ◽  
pp. 384
Author(s):  
Daniel E. Hagaman ◽  
Jossana A. Damasco ◽  
Joy Vanessa D. Perez ◽  
Raniv D. Rojo ◽  
Marites P. Melancon
Keyword(s):  
Prostate Cancer ◽  
Bone Metastases ◽  
Advanced Prostate Cancer ◽  
Bone Fractures ◽  
Diagnosis And Treatment ◽  
Survival Times ◽  
Preclinical Research ◽  
Relieve Pain ◽  
Translational Models

Patients with advanced prostate cancer can develop painful and debilitating bone metastases. Currently available interventions for prostate cancer bone metastases, including chemotherapy, bisphosphonates, and radiopharmaceuticals, are only palliative. They can relieve pain, reduce complications (e.g., bone fractures), and improve quality of life, but they do not significantly improve survival times. Therefore, additional strategies to enhance the diagnosis and treatment of prostate cancer bone metastases are needed. Nanotechnology is a versatile platform that has been used to increase the specificity and therapeutic efficacy of various treatments for prostate cancer bone metastases. In this review, we summarize preclinical research that utilizes nanotechnology to develop novel diagnostic imaging tools, translational models, and therapies to combat prostate cancer bone metastases.

scholarly journals IMPDH2 and HPRT expression and a prognostic significance in preoperative and postoperative patients with osteosarcoma

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Parunya Chaiyawat ◽  
Areerak Phanphaisarn ◽  
Nutnicha Sirikaew ◽  
Jeerawan Klangjorhor ◽  
Viraporn Thepbundit ◽  
...  
Keyword(s):  
Overall Survival ◽  
Cox Regression ◽  
Expression Patterns ◽  
Prognostic Significance ◽  
Drug Repurposing ◽  
Survival Times ◽  
Metabolizing Enzymes ◽  
Hypoxanthine Guanine Phosphoribosyltransferase ◽  
High Grade Osteosarcoma ◽  
Enneking Stage

AbstractOsteosarcoma is one of the most aggressive bone tumors in children and adolescents. Development of effective therapeutic options is still lacking due to the complexity of the genomic background. In previous work, we applied a proteomics-guided drug repurposing to explore potential treatments for osteosarcoma. Our follow-up study revealed an FDA-approved immunosuppressant drug, mycophenolate mofetil (MMF) targeting inosine-5′-phosphate dehydrogenase (IMPDH) enzymes, has an anti-tumor effect that appeared promising for further investigation and clinical trials. Profiling of IMPDH2 and hypoxanthine–guanine phosphoribosyltransferase (HPRT), key purine-metabolizing enzymes, could deepen understanding of the importance of purine metabolism in osteosarcoma and provide evidence for expanded use of MMF in the clinic. In the present study, we investigated levels of IMPDH2, and HPRT in biopsy of 127 cases and post-chemotherapy tissues in 20 cases of high-grade osteosarcoma patients using immunohistochemical (IHC) analysis. Cox regression analyses were performed to determine prognostic significance of all enzymes. The results indicated that low levels of HPRT were significantly associated with a high Enneking stage (P = 0.023) and metastatic status (P = 0.024). Univariate and multivariate analyses revealed that patients with low HPRT expression have shorter overall survival times [HR 1.70 (1.01–2.84), P = 0.044]. Furthermore, high IMPDH2/HPRT ratios were similarly associated with shorter overall survival times [HR 1.67 (1.02–2.72), P = 0.039]. Levels of the enzymes were also examined in post-chemotherapy tissues. The results showed that high IMPDH2 expression was associated with shorter metastasis-free survival [HR 7.42 (1.22–45.06), P = 0.030]. These results suggest a prognostic value of expression patterns of purine-metabolizing enzymes for the pre- and post-chemotherapy period of osteosarcoma treatment.

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