Two modes of phloem loading have been proposed, apoplastic and symplastic, depending on the structure of sieve element-companion cell complexes (SE-CCCs) in minor vein phloem. Species are usually classified as either apoplastic or symplastic loaders although the cytology of SE-CCCs in minor veins of the majority of plants indicates that both mechanisms can be simultaneously involved in phloem loading. The functions of structurally different SE-CCCs in minor veins of the stachyose-translocating plant Alonsoa meridionalis were examined. A stachyose synthase gene, AmSTS1, was expressed in intermediary cells but not in the ordinary companion cell of the same vein. In contrast, sucrose transporter AmSUT1 protein was present in ordinary companion cells but not in the neighbouring intermediary cells. These data reveal the principles of phloem sap formation in A. meridionalis and, probably, in many other dicots. The two types of SE-CCCs within one and the same minor vein load different carbohydrates, using contrasting mechanisms for their delivery into the phloem. Lateral sieve pores in the minor vein phloem lead to mixing of the carbohydrates soon after loading. While symplastic and apoplastic pathways can function simultaneously during phloem loading, they are separated at the level of different SE-CCCs combined in phloem endings.
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http://dx.doi.org/10.1093/jxb/erp074 | DOI Listing |
Postgrad Med
January 2025
Department of Internal Medicine, Lankenau Medical Center, Wynnewood, PA, USA.
Venous thromboembolism (VTE), consisting of both deep vein thrombosis (DVT) and pulmonary embolism (PE), is an extremely common condition both in the United States and worldwide. Not only is the diagnosis associated with significant morbidity and mortality for patients but it also imposes a deleterious financial burden on the US healthcare system. Diagnosis may be challenging due to variability in clinical presentation and requires a sequential workup including assessment of clinical pretest probability for VTE, D-dimer testing, and imaging.
View Article and Find Full Text PDFJ Mol Cell Cardiol Plus
March 2024
Department of Physiology, Cardiovascular Research Institute Maastricht (CARIM), University Maastricht, Maastricht, the Netherlands.
Introduction: Repetitive focal and rotational activation patterns are currently used as additional ablation targets for atrial fibrillation (AF). However, there is no evidence that all these detected targets are actual sources of AF. In this paper, we present an approach that detects and ranks AF activation patterns not only based on the degree of pattern repetitiveness but also on the extent to which they are able to entrain their vicinity.
View Article and Find Full Text PDFDiabetology (Basel)
October 2024
Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.
Objectives: This study aims to examine the association between state Medicaid coverage of podiatry services and the outcomes of beneficiaries with new diabetic foot ulcers (DFUs).
Methods: Medicaid beneficiaries who developed a DFU between 2010 and 2015 were identified using the PearlDiver claims database. The states were categorized into covered states (CS) and non-covered states (NCS) based on podiatric coverage during the study period.
Acta Med Philipp
November 2024
Division of Thoracic, Cardiac and Vascular Surgery, Department of Surgery, College of Medicine and Philippine General Hospital, University of the Philippines Manila.
Objective: To describe the treatment outcomes of patients who underwent Percutaneous Transluminal Angioplasty (PTA) for Central Vein Occlusive Disease (CVOD) in end-stage kidney disease and determine the association between patient profile and treatment outcomes.
Methods: A single-institution, retrospective review of patients aged 18 and above with end-stage kidney disease who underwent PTA for CVOD in the University of the Philippines - Philippine General Hospital (UP-PGH) from January 1, 2013, to December 31, 2022, was performed. These patients' demographic and clinical profiles were evaluated using means, frequencies, and percentages.
Vasc Endovascular Surg
January 2025
Vascular Surgery Department, Hospital Militar Central, Bogotá, Colombia.
Background: Chronic limb-threatening ischemia (CLTI) leads to decreased quality of life and increased disease burden, resulting in progressive patient deterioration, limb amputation, and mortality.
Objectives: This study aims to present the outcomes of a Latin American experience using the open distal venous arterialization (DVA) technique for no-option limb salvage in a high volume CLTI center.
Methods: A retrospective case series study was performed including patients from 2018 to 2022 using a population from Bogotá, Colombia.
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