In biology, the activity of enzymes is usually regulated by feedback loops, which enables direct communication between enzymes and the state of the cell. In a similar manner, with the intention to have automated activity regulation, the therapeutic effect of a photosensitizer () is shown to be reduced through a negative feedback loop initiated by the photosensitizer. Photodynamic action produces cytotoxic O and this reactive oxygen species reacts with ascorbate, generating HO. Peroxide-mediated oxidation of the photosensitizer auxiliary group leads to the formation of inactive from the parent photosensitizer. is shown to accumulate in mitochondria, and cell viability is shown to decrease significantly with compared to the loop end product, . Photoinduced enhancement of fluorescence indicates the formation of inactive under cellular conditions, and enhanced fluorescence acts as a reporter for the activity of the photosensitizer. We present the first example of PDT autoinactivation, and such a feedback control mechanism would enable a decrease in post-therapy side effects.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6681998 | PMC |
| http://dx.doi.org/10.1021/acsomega.9b01410 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Experiences, perceptions and ethical considerations of the malaria infection study in Thailand.
BMC Med Ethics
January 2025
Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, 420/6 Rajvithi Road, Thunphayathai, Bangkok, 10400, Thailand.
Background: Thailand has made significant progress in malaria control efforts in the past decade, with a decline in the number of reported cases. However, due to cross-border movements over the past 5 years, reported malaria cases in Thailand have risen. The Malaria Infection Study in Thailand (MIST) involves deliberate infection of healthy volunteers with Plasmodium vivax malaria parasites, and the assessment of the efficacy of potential vaccine and drug candidates in order to understand acquired protection against malaria parasites.
View Article and Find Full Text PDFDesign and Implementation of universal converter using ANN controller.
Sci Rep
January 2025
School of ECE, Adama Science and Technology University, Adama, Ethiopia.
This paper details the hardware implementation of a Universal Converter controlled by an Artificial Neural Network (ANN), utilizing key components such as six Insulated Gate Bipolar Transistors (IGBTs), two inductors, and two capacitors for energy storage and voltage smoothing. A Digital Signal Processor (DSP) serves as the core controller, processing real-time input and feedback signals, including voltage and current measurements, to dynamically manage five operational modes: rectifier buck, inverter boost, DC-DC buck, DC-DC boost, and AC voltage control. The pre-trained ANN algorithm generates pulse-width modulation (PWM) signals to control the switching of the IGBTs, optimizing timing and duty cycles for efficient operation.
View Article and Find Full Text PDFSelf-Management Strategies for Low Back Pain Among Horticulture Workers: Protocol for a Type II Hybrid Effectiveness-Implementation Study.
JMIR Res Protoc
January 2025
Department of Pediatrics, School of Medicine, University of Virginia, Charlottesville, VA, United States.
Background: Low back pain (LBP) is highly prevalent and disabling, especially in agriculture sectors. However, there is a gap in LBP prevention and intervention studies in these physically demanding occupations, and to date, no studies have focused on horticulture workers. Given the challenges of implementing interventions for those working in small businesses, self-management offers an attractive and feasible option to address work-related risk factors and manage LBP.
View Article and Find Full Text PDFBackground: Mental health remains among the top 10 leading causes of disease burden globally, and there is a significant treatment gap due to limited resources, stigma, limited accessibility, and low perceived need for treatment. Problem Management Plus, a World Health Organization-endorsed brief psychological intervention for mental health disorders, has been shown to be effective and cost-effective in various countries globally but faces implementation challenges, such as quality control in training, supervision, and delivery. While digital technologies to foster mental health care have the potential to close treatment gaps and address the issues of quality control, their development requires context-specific, interdisciplinary, and participatory approaches to enhance impact and acceptance.
View Article and Find Full Text PDFHSP27/IL-6 axis promotes OSCC chemoresistance, invasion and migration by orchestrating macrophages via a positive feedback loop.
Cell Biol Toxicol
January 2025
Department of Oral Anatomy and Physiology, Hospital of Stomatology, Jilin Provincial Key Laboratory of Oral Biomedical Engineering, Jilin University, Changchun, 130021, China.
Novel strategies to disrupt tumor progression have emerged from studying the interactions between tumor cells and tumor-associated macrophages (TAMs). However, the molecular mechanisms of interactions between tumor cells and TAMs underlying oral squamous cell carcinoma (OSCC) progression have not been fully elucidated. This study explored the molecular mechanism of the HSP27/IL-6 axis in OSCC chemoresistance, invasion, and migration.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!