An epidemic model with distributed time delay is derived to describe the dynamics of infectious diseases with varying immunity. It is shown that solutions are always positive, and the model has at most two steady states: disease-free and endemic. It is proved that the disease-free equilibrium is locally and globally asymptotically stable. When an endemic equilibrium exists, it is possible to analytically prove its local and global stability using Lyapunov functionals. Bifurcation analysis is performed using DDE-BIFTOOL and traceDDE to investigate different dynamical regimes in the model using numerical continuation for different values of system parameters and different integral kernels.
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http://dx.doi.org/10.1007/s11538-009-9458-y | DOI Listing |
AIDS Care
January 2025
Department of Knowledge Management, Sociedad Integral de Especialistas en Salud (SIES Salud IPS), Bogotá, Colombia.
The most significant progress in addressing the HIV/AIDS epidemic has been the development of antiretroviral therapy (ART). However, ensuring a high degree of treatment adherence is necessary to prevent resistance and disease progression. We conducted a cross-sectional study to evaluate adherence to ART through the calculation of the medication possession ratio (MPR) and to identify risk factors for suboptimal adherence in a cohort of HIV-positive patients receiving care at a Colombian healthcare institution across 16 cities.
View Article and Find Full Text PDFRheumatology (Oxford)
January 2025
Department of Rheumatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland.
Objectives: The 2022 European Society of Cardiology and European Respiratory Society (ESC/ERS) Guidelines for pulmonary arterial hypertension (PAH) recommend risk stratification to optimize management. However, the performance of generic PAH risk stratification tools in patients with systemic sclerosis (SSc)-associated PAH remains unclear. Our objective was to identify the most accurate approach for risk stratification at SSc-PAH diagnosis.
View Article and Find Full Text PDFDiscov Oncol
January 2025
Department of General Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei, 230000, China.
Aim: To construct a predictive model based on the LODDS stage established for patients with late-onset colon adenocarcinoma to enhance survival stratification.
Methods: Late-onset colon adenocarcinoma data were obtained from the public database. After determining the optimal LODDS truncation value for the training set via X-tile software, we created a new staging system by integrating the T stage and M stage.
J Viral Hepat
March 2025
Department of Biomedical Informatics, Ajou University School of Medicine, Suwon, Republic of Korea.
Alpha-fetoprotein (AFP) level and its changes in chronic hepatitis B (CHB) may influence the risk of future hepatocellular carcinoma (HCC). This study aims to evaluate the HCC risk in CHB patients with no overt HCC but with elevated AFP level and to explore the prognostic role of longitudinal changes in AFP and liver-related laboratory values. This multicentre cohort study included 10,639 CHB patients without a history of HCC from seven medical facilities in South Korea.
View Article and Find Full Text PDFHepatol Commun
February 2025
Department of Anesthesiology, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
Background: Cell therapy demonstrates promising potential as a substitute therapeutic approach for liver cirrhosis. We have developed a strategy to effectively expand murine and human hepatocyte-derived liver progenitor-like cells (HepLPCs) in vitro. The primary objective of the present study was to apply HepLPCs to the treatment of liver cirrhosis and to elucidate the underlying mechanisms responsible for their therapeutic efficacy.
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