A study was made of the time courses of growth promotion and the reversal of growth promotion upon the addition and withdrawal of various auxins. Growth promotion by 1-naphthaleneacetic acid (NAA) and 2,4-dichlorophenoxyacetic acid (2,4-D) occurs more slowly and is less vigorous than growth promotion by the same concentration of indoleacetic acid (IAA).The time required for the reversal of the stimulation of elongation by auxin is many times greater for 2,4-D-stimulated growth than for IAA- or NAA-stimulated growth (80 min vs. about 10 min). This difference appears to be due to the sluggish exit of 2,4-D since (1) experiments with labeled auxins show that 2,4-D moves out of the tissue more slowly than IAA, and (2) it is possible to shorten the time required for a decline in elongation rate after the removal of 2,4-D to 13 min by adding an auxin antagonist (p-chlorophenoxyisobutyric acid).The rapid reversal of the hormonal stimulation of growth is discussed in relation to possible mechanisms of action of auxin.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1007/BF00387663 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Docetaxel-Loaded Electrospun Nanofibrous Mats for Local Chemotherapy Targeting Positive Surgical Margins in Prostate Cancer.
Mol Pharm
March 2025
Department and Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
Positive surgical margins following radical prostatectomy significantly contribute to tumor recurrence. While systemic chemotherapy demonstrates limited efficacy in this context, local chemotherapy drug delivery systems based on nanomaterials offer promising strategies to address this issue by modifying drug release kinetics and distribution, thereby enhancing antitumor effects while minimizing the toxicities associated with systemic chemotherapy. In this study, we utilized electrospun nanofibrous mats loaded with docetaxel for sustained drug delivery.
View Article and Find Full Text PDFStaged hybrid approach for acute type A aortic dissection: zone 2 arch replacement and completion thoracic endovascular aortic repair upon indication.
Eur J Cardiothorac Surg
March 2025
Department of Cardiothoracic Surgery, Radboud University Medical Center, Nijmegen, Netherlands.
Objectives: This study evaluates a staged selective hybrid approach for acute type A aortic dissection. The approach involves a zone 2 aortic arch replacement with debranching of the brachiocephalic trunk and left common carotid artery to create a landing zone for thoracic endovascular aortic repair. This repair is performed either preemptively in the subacute phase to promote remodelling or electively in the chronic phase to manage aneurysm formation.
View Article and Find Full Text PDFConditioned medium of engineering macrophages combined with soluble microneedles promote diabetic wound healing.
PLoS One
March 2025
Medical School of Chinese PLA, Department of Plastic and Reconstructive Surgery, First Medical Center of Chinese PLA General Hospital, Beijing, China.
Diabetic wounds have a profound effect on both the physical and psychological health of patients, highlighting the urgent necessity for novel treatment strategies and materials. Macrophages are vital contributors to tissue repair mechanisms. Macrophage conditioned medium contains various proteins and cytokines related to wound healing, indicating its potential to improve recovery from diabetic wound.
View Article and Find Full Text PDFIntegrative approach to decipher pharmacological mechanism of Cinnamomum zeylanicum essential oil in prostate cancer.
Med Oncol
March 2025
Centre for Biotechnology, Siksha O Anusandhan (Deemed to Be University), Bhubaneswar, Odisha, 751003, India.
Prostate cancer has garnered much importance in recent years due to its rising incidence and mortality among men worldwide. The ineffectiveness of existing therapies and adverse events associated with conventional treatment have led patients to turn towards traditional medicine for the management of prostate cancer. Cinnamomum zeylanicum bark essential oil (CZEO) possesses promising anticancer properties, yet the exact mechanism of action of CZEO for the management of prostate cancer remains unclear.
View Article and Find Full Text PDFInvestigating cuproptosis and mitochondrial dysfunction in brain cells: uncovering novel mechanisms and biomarkers for Parkinson's disease.
Metab Brain Dis
March 2025
Xinxiang Key Laboratory of Targeted Intervention for Brain Cell Injury, Sanquan College of Xinxiang Medical University, Xinxiang, 453000, China.
Parkinson's disease (PD) is a chronic neurodegenerative condition marked by the gradual degeneration of dopaminergic neurons, resulting in a range of disabling motor and non-motor symptoms. Despite advances, the molecular mechanisms underlying PD remain elusive, and effective biomarkers and therapeutic targets are limited. Recent studies suggest that mitochondrial dysfunction and dysregulated cellular metabolism are central to PD pathogenesis.
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!