Reynolds s lead citrate

For the ultrastructural analysis, we applied the EM-BSEM approach, which was described in detail [65 (link)]. Briefly, deteriorated segments of BHVs and AVs were fixed in 10% neutral phosphate-buffered formalin (B06-003, ErgoProduction, Saint Petersburg, Russia), postfixed and stained in 1% phosphate-buffered osmium tetroxide (OsO₄, 19110, Electron Microscopy Sciences, Hatfield, PA, USA), dehydrated in an ascending ethanol series (Kemerovo Pharmaceutical Plant, Kemerovo, Russia) and isopropanol (06-002, ErgoProduction, Saint Petersburg, Russia), stained in 2% alcoholic uranyl acetate (22400-2, Electron Microscopy Sciences, Hatfield, PA, USA), impregnated with acetone (6-09-20-03-83, EKOS-1, Moscow, Russia): epoxy resin (1:1) and epoxy resin (Araldite 502, 13900, Electron Microscopy Sciences, Hatfield, PA, USA), embedded into epoxy resin, grinded, polished, and counterstained with Reynolds’s lead citrate (17810, Electron Microscopy Sciences, Hatfield, PA, USA), sputter-coated with carbon (Leica EM ACE200, Leica Microsystems, Wetzlar, Germany), and visualised by means of backscattered scanning electron microscopy (S-3400N, Hitachi, Tokyo, Japan) in accordance with an EM-BSEM procedure similar to the previously published literature [11 (link),18 (link),66 (link),67 (link),68 (link),69 (link)].

After the electrospinning, TEVGs were sputter coated with gold and palladium (Leica EM ACE200, Leica Microsystems, Wetzlar, Germany) and visualised by scanning electron microscopy (S-3400N, Hitachi, Tokyo, Japan).
The second midgraft segment was fixed in 10% neutral phosphate buffered formalin (B06-003, ErgoProduction, Saint Petersburg, Russia), postfixed and stained in 1% phosphate buffered osmium tetroxide (OsO₄, 19110, Electron Microscopy Sciences, Hatfield, PA, USA), dehydrated in ascending ethanol series (Kemerovo Pharmaceutical Plant, Kemerovo, Russia) and isopropanol (06-002, ErgoProduction, Saint Petersburg, Russia), stained in 2% alcoholic uranyl acetate (22400-2, Electron Microscopy Sciences, Hatfield, PA, USA), impregnated with acetone (6-09-20-03-83, EKOS-1, Moscow, Russia): epoxy resin (1:1) and epoxy resin (Araldite 502, 13900, Electron Microscopy Sciences, Hatfield, PA, USA), embedded into epoxy resin, grinded, polished, counterstained with Reynolds’s lead citrate (17810, Electron Microscopy Sciences, Hatfield, PA, USA), sputter coated with carbon (Leica EM ACE200, Leica Microsystems, Wetzlar, Germany) and visualised by means of backscattered scanning electron microscopy (S-3400N, Hitachi, Tokyo, Japan) in accordance with an EM-BSEM (embedding and backscattered scanning electron microscopy) procedure as previously described [25 (link),35 (link)].