Gene/Protein Disease Symptom Drug Enzyme Compound
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Fundamental knowledge of spermatozoa cryobiology can assist with optimizing cryopreservation protocols needed for genetic management of the endangered black-footed ferret. Objectives were to characterize semen osmolality and assess the influence of two media at various osmolalities on sperm viability. We examined the influence of Ham's F10 +Hepes medium (H) at 270, 400, 500 or 700 mOsm (adjusted with sucrose, a nonpermeating cryoprotectant) and TEST Yolk Buffer (TYB) with 0% (300 mOsm) versus 4% (900 mOsm) glycerol (a permeating cryoprotectant). Electroejaculates (n=16) were assessed for osmolality using a vapor pressure osmometer. For media comparison, semen (n=5) was collected in TYB 0%, split into six aliquots, and diluted in H270, H400, H500, H700, and TYB 0% or TYB 4%. Each sample was centrifuged (300 g, 8 min), resuspended in respective medium, and maintained at 37 degrees C for 3h. Sperm motility and forward progression were monitored every 30 min for 3h post-washing. Acrosomal integrity was monitored at 0 and 60 min post-washing. Results demonstrated that black-footed ferret semen has a comparatively high osmolality (mean+/-SEM, 513.1+/-32.6 mOsm; range, 366-791 mOsm). Ferret spermatozoa were sensitive to hyperosmotic stress. Specifically, sperm motility was more susceptible (P<0.01) to hyperosmotic conditions than acrosomal integrity, and neither were influenced (P>0.05) by hypotonic solutions. Exposure to TYB 4% glycerol retained more (P<0.01) sperm motility than a hyperosmotic Ham's (700 mOsm). These findings will guide the eventual development of assisted breeding with cryopreserved sperm contributing to genetic management of this rare species.
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PMID:Sperm viability in the black-footed ferret (Mustela nigripes) is influenced by seminal and medium osmolality. 1671 29

Titanium compounds have demonstrated great interfacial properties with biological tissues whereas a wide variety of polyurethanes have also been successfully probed in medical applications. However, studies about hybrids based on polyurethanes/TiO2 for medical applications are scarce. The aim of this work is to design novel biodegradable hybrid materials based on polyurethanes/TiO2 (80% organic-20% inorganic) and to perform a preliminary study of the potential applications in bone regeneration. The hybrids have been prepared by a sol-gel reaction using titanium isopropoxide as precursor of the inorganic component and polyurethane as the organic one. A series of polyurethanes has been prepared using different polyesters glycol succinate as soft segment, and 1,6-diisocyanatohexane (HDI) and butanediol (BD) as linear hard segment. The spectroscopy techniques used allow to confirm the formation of the required polyurethanes by the identification of bands related to carboxylic groups (COOH), and the amine groups (NH), and also the TiOH bonds and the bonds related to the interconnected network between the inorganic and the organic components from hybrids. The results from SEM/EDS show a homogeneous distribution of the inorganic component into the organic matrix. The nontoxic character of the hybrid (H400) was probed using MG-63 cell line with over 90% of cell viability. Finally, the formation of a hydroxyapatite layer in the material surface after 21days of soaking in SBF shows the bioactive character.
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PMID:Novel non-cytotoxic, bioactive and biodegradable hybrid materials based on polyurethanes/TiO2 for biomedical applications. 2841 75