Morphology and function of preserved microvascular arterial grafts: an experimental study in rats

The aim of this study is to examine the morphology and function and small-caliber, arterial grafts after preservation in the University of Wisconsin solution (UW). Rat carotid arteries were stored in UW (n = 10) or in phosphate-buffered saline (PBS) (n = 10) for 1, 3, 7, and 14 days and were examined with light microscopy (LM) and scanning electron microscopy (SEM). Rat aortic preparations were stored in UW or PBS for 1 hour, 24 hours, 72 hours, 7 days, and 14 days and assessed for functional responses (stimulated contraction and endothelium-dependent relaxation). Segments (5 mm) of rat carotid arteries were stored in UW or PBS for 3 days, 7 days, and 14 days and orthotopically implanted as autografts and allografts. No immunosuppressive or anticoagulant agents were used. After 28 days of implantation, the grafts were assessed for patency and excised for LM and SEM. In UW, the endothelial layer remained intact up to 9 days of storage. In PBS, the endothelial layer showed deterioration after 1 day and was completely lost after 3 days. Functional responses were demonstrated to exist for as long as 7 days storage in UW. In PBS, no responses could be evoked after 24 hours storage. Autografts preserved in UW for 3 days (n = 6), 7 days (n = 6), and 14 days (n = 6) showed patency rates of 83.3%, 66.6%, and 66.6%, respectively, whereas patency rates of allografts were 66.6%, 33.3%, and 33.3%, respectively. Autografts stored in PBS for 3 days (n = 6), 7 days (n = 6), and 14 days (n = 6) showed patency rates of 33.3%, 33.3%, and 50%, respectively, whereas patency rates of allografts were 16.7%, 0%, and 33.3%, respectively. The UW preserved autografts showed normal morphology. All other groups showed vessel wall degeneration which in the allograft groups, were accompanied by lymphocellular infiltration. In conclusion, the endothelial layer and vessel wall of arteries are adequately preserved in UW. Functional responses are retained up to 14 days storage in UW, but, are lost after 24 hours storage in PBS. Autograft implantation studies accordingly show good performance of arterial segments preserved in UW, whereas allografts are subject to degradation as a result of rejectio

FIGURE 6 in National Herbarium Plant Collecting Programme reveals new country and provincial distribution records from South African National Parks (Apocynaceae, Asteraceae & Xanthorrhoeaceae: Asphodeloideae)

FIGURE 6. Known distribution of Doellia cafra in southern Africa,. New localities, ̝. Specimens housed at PRE and NBG.Published as part of <i>Bester, Stoffel P., Herman, Paul P.J. & Klopper, Ronell R., 2012, National Herbarium Plant Collecting Programme reveals new country and provincial distribution records from South African National Parks (Apocynaceae, Asteraceae & Xanthorrhoeaceae: Asphodeloideae), pp. 44-56 in Phytotaxa 62 (1)</i> on page 50, DOI: 10.11646/phytotaxa.62.1.9, <a href="http://zenodo.org/record/10087349">http://zenodo.org/record/10087349</a&gt

FIGURE 2 in National Herbarium Plant Collecting Programme reveals new country and provincial distribution records from South African National Parks (Apocynaceae, Asteraceae & Xanthorrhoeaceae: Asphodeloideae)

FIGURE 2. Known distribution of Orthanthera albida,. New localities, ̝. Specimens housed at PRE and NBG.Published as part of <i>Bester, Stoffel P., Herman, Paul P.J. & Klopper, Ronell R., 2012, National Herbarium Plant Collecting Programme reveals new country and provincial distribution records from South African National Parks (Apocynaceae, Asteraceae & Xanthorrhoeaceae: Asphodeloideae), pp. 44-56 in Phytotaxa 62 (1)</i> on page 46, DOI: 10.11646/phytotaxa.62.1.9, <a href="http://zenodo.org/record/10087349">http://zenodo.org/record/10087349</a&gt

FIGURE 9 in National Herbarium Plant Collecting Programme reveals new country and provincial distribution records from South African National Parks (Apocynaceae, Asteraceae & Xanthorrhoeaceae: Asphodeloideae)

FIGURE 9. Known distribution of Trachyandra asperata var. basutoensis,. New localities, ̝. Specimens housed at PRE and NBG.Published as part of <i>Bester, Stoffel P., Herman, Paul P.J. & Klopper, Ronell R., 2012, National Herbarium Plant Collecting Programme reveals new country and provincial distribution records from South African National Parks (Apocynaceae, Asteraceae & Xanthorrhoeaceae: Asphodeloideae), pp. 44-56 in Phytotaxa 62 (1)</i> on page 54, DOI: 10.11646/phytotaxa.62.1.9, <a href="http://zenodo.org/record/10087349">http://zenodo.org/record/10087349</a&gt

National Herbarium Plant Collecting Programme reveals new country and provincial distribution records from South African National Parks (Apocynaceae, Asteraceae & Xanthorrhoeaceae : Asphodeloideae)

New country and provincial distribution records for South Africa of specimens collected mainly in various South African National Parks are reported on here. The taxa included in this contribution are of Orthanthera albida (Apocynaceae), Doellia cafra (Asteraceae), Bulbine ophiophylla (Xanthorrhoeaceae: Asphodeloideae) and Trachyandra asperata var. basutoensis (Xanthorrhoeaceae: Asphodeloideae)

FIGURE 5 in National Herbarium Plant Collecting Programme reveals new country and provincial distribution records from South African National Parks (Apocynaceae, Asteraceae & Xanthorrhoeaceae: Asphodeloideae)

FIGURE 5. Doellia cafra (photographs by P.P.J. Herman). A. Capitula showing the outer female florets in many rows and a few central disc florets. B. Outer female floret showing the filiform corolla and exserted style. C. Cypsela showing the pappus bristles. Pulicaria scabra (photographs by P.P.J. Herman). D. Capitula showing the outer female florets in one row and many disc florets. E. Outer female floret with short but distinct corolla limb. F. Cypsela showing the outer pappus scales fused in a corona and inner pappus bristles. A–C from Koekemoer 2693 (PRE). D from Leendertz 1127 (PRE). E from Van Rooyen 2314 (PRE). F from Hafström Herb. H960 (PRE). Scale bars all 4 mm.Published as part of <i>Bester, Stoffel P., Herman, Paul P.J. & Klopper, Ronell R., 2012, National Herbarium Plant Collecting Programme reveals new country and provincial distribution records from South African National Parks (Apocynaceae, Asteraceae & Xanthorrhoeaceae: Asphodeloideae), pp. 44-56 in Phytotaxa 62 (1)</i> on page 49, DOI: 10.11646/phytotaxa.62.1.9, <a href="http://zenodo.org/record/10087349">http://zenodo.org/record/10087349</a&gt

FIGURE 8 in National Herbarium Plant Collecting Programme reveals new country and provincial distribution records from South African National Parks (Apocynaceae, Asteraceae & Xanthorrhoeaceae: Asphodeloideae)

FIGURE 8. Known distribution of Bulbine ophiophylla,. New localities, ̝. Specimens housed at PRE and NBG.Published as part of <i>Bester, Stoffel P., Herman, Paul P.J. & Klopper, Ronell R., 2012, National Herbarium Plant Collecting Programme reveals new country and provincial distribution records from South African National Parks (Apocynaceae, Asteraceae & Xanthorrhoeaceae: Asphodeloideae), pp. 44-56 in Phytotaxa 62 (1)</i> on page 53, DOI: 10.11646/phytotaxa.62.1.9, <a href="http://zenodo.org/record/10087349">http://zenodo.org/record/10087349</a&gt

FIGURE 7 in National Herbarium Plant Collecting Programme reveals new country and provincial distribution records from South African National Parks (Apocynaceae, Asteraceae & Xanthorrhoeaceae: Asphodeloideae)

FIGURE 7. Known distribution of Pulicaria scabra in southern Africa. All specimens housed at PRE and NBG.Published as part of <i>Bester, Stoffel P., Herman, Paul P.J. & Klopper, Ronell R., 2012, National Herbarium Plant Collecting Programme reveals new country and provincial distribution records from South African National Parks (Apocynaceae, Asteraceae & Xanthorrhoeaceae: Asphodeloideae), pp. 44-56 in Phytotaxa 62 (1)</i> on page 51, DOI: 10.11646/phytotaxa.62.1.9, <a href="http://zenodo.org/record/10087349">http://zenodo.org/record/10087349</a&gt