During slow freezing, spermatozoa undergo membrane alterations that compromise their ability of fertilizing. These alterations are cause either by cold shock or by the use of cryoprotectants known to be cytotoxic. However, little is known about the membrane changes that occurred during freezing. Here, we combined Generalized Polarization (GP), Time-resolved Fluorescence and laurdan fluorescence properties to investigate the changes in membrane fluidity and dynamics during slow freezing of bull sperm. We successfully demonstrated that laurdan may be distributed in three different local environments that correspond to different membrane lipid composition. These environments wont behave the same way when the cells will be subjected to either a chemical treatment (adding the cryoprotectants) or a physical treatment (freezing).
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http://dx.doi.org/10.1016/j.cryobiol.2019.10.196 | DOI Listing |
J Pineal Res
January 2025
Institute of Physiology, Sleep Research & Clinical Chronobiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.
While artificial light in urban environments was previously thought to override seasonality in humans, recent studies have challenged this assumption. We aimed to explore the relationship between seasonally varying environmental factors and changes in sleep architecture in patients with neuropsychiatric sleep disorders by comparing two consecutive years. In 770 patients, three-night polysomnography was performed at the Clinic for Sleep & Chronomedicine (St.
View Article and Find Full Text PDFPharmaceutics
December 2024
Nanofaber S.r.l., Via Anguillarese 301, 00123 Rome, Italy.
Background/objectives: This study aimed to develop a novel nanotechnological slow-release drug delivery platform based on hyaluronic acid Microsponge (MSP) for the subcutaneous administration of methotrexate (MTX) in the treatment of rheumatoid arthritis (RA). RA is a chronic autoimmune disease characterized by joint inflammation and damage, while MTX is a common disease-modifying antirheumatic drug (DMARD), the conventional use of which is limited by adverse effects and the lack of release control.
Methods: MSP were synthesized as freeze-dried powder to increase their stability and allow for a facile reconstitution prior to administration and precise MTX dosing.
Cryobiology
January 2025
Specialized Surgical Hospital "Doctor Malinov", 46, Gotse Delchev blvd., 1860, Sofia, Bulgaria.
The cryopreservation of human spermatozoa is an integral part of cryobiology, aiming to support the in-vitro fertilization. The latter relies on the availability of as much as possible reproductively active spermatozoa, whose number after thawing decreases due to the accompanied freezing injury and the cytotoxicity of cryoprotectants. An innovative option to circumvent these obstacles is to make the freezing interface non-wettable, by coating it with rapeseed oil soot possessing intrinsic cryoprotective properties, delaying the ice formation and possibly providing identical rates of intracellular dehydration and extracellular crystallization.
View Article and Find Full Text PDFBiomater Adv
December 2024
College of Biological Science and Engineering, Fuzhou University, No. 2 Xueyuan Road, Fuzhou 350108, China; Fujian Key Laboratory of Medical Instrument and Pharmaceutical Technology, Fuzhou University, No. 2 Xueyuan Road, Fuzhou 350108, China. Electronic address:
In anterior cruciate ligament (ACL) repair methods, the continuous enzymatic erosion of synovial fluid can impede healing and potentially lead to repair failure, as well as exacerbate articular cartilage wear, resulting in joint degeneration. Inspired by the blood clot during medial collateral ligament healing, we developed a composite scaffold comprising collagen (1 %, w/v) and polyvinyl alcohol (5 %, w/v) combined with platelet-rich plasma (PRP). The composite scaffold provides a protective barrier against synovial erosion for the ruptured ACL, while simultaneously facilitating tissue repair, thereby enhancing the efficacy of ACL repair techniques.
View Article and Find Full Text PDFTheriogenology
December 2024
University of Utrecht, Department of Clinical Sciences, Netherlands.
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