Local administration of simvastatin on bone regeneration: an in vivo experimental study in Guinea pigs

Bone possesses an intrinsic regenerative capacity, which can be compromised by aging, disease, trauma, and iatrogenesis (e.g. tumor resection, pharmacological). At present, autografts and allografts are the principal biological treatments available to replace large bone segments, but both entail several limitations that reduce wider use and consistent success. The use of decellularized extracellular matrices (ECM), often derived from xenogeneic sources, has been shown to favorably influence the immune response to injury and promote site-appropriate tissue regeneration. Decellularized bone ECM (dbECM), utilized in several forms — whole organ, particles, hydrogels — has shown promise in both in vitro and in vivo animal studies to promote osteogenic differentiation of stem/progenitor cells and enhance bone regeneration. However, dbECM has yet to be investigated in clinical studies, which are needed to determine the relative efficacy of this emerging biomaterial as compared with established treatments. This mini-review highlights the recent exploration of dbECM as a biomaterial for skeletal tissue engineering and considers modifications on its future use to more consistently promote bone regeneration.

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Involvement of 5-Hydroxytryptamine in Platelet Aggregation In Vivo in Rats and Guinea Pigs

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646615 ◽

1989 ◽

Vol 61 (03) ◽

pp. 463-467 ◽

Cited By ~ 3

Author(s):

G M Smith

Keyword(s):

Platelet Count ◽

Guinea Pigs ◽

Platelet Adhesion ◽

Adenosine Diphosphate ◽

Rate Of Return ◽

Low Doses ◽

Dose Dependent ◽

Higher Doses ◽

Rat Platelets

SummaryIn this study, 5-hydroxytryptamine (5-HT) caused a dose- dependent fall in the circulating platelet count suggesting that 5-HT receptors are activated in rat platelets to cause platelet adhesion and aggregation. When low doses of adenosine diphosphate (ADP) were simultaneously injected with 5-HT, there was a significant potentiation of the responses to ADR Ketanserin significantly reduced the potentiated responses. When higher doses of ADP were infused with bolus injections of 5-HT there was no potentiation and ketanserin did not reduce these responses. Ketanserin did not inhibit the collagen-induced fall in circulating platelet count, but did significantly increase the rate of return to the basal platelet count compared with control. 5-HT did not cause a fall in platelet count in guinea-pigs

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Inhibition of Human and Animal Platelet Adhesiveness to Glass Bead Columns by Adenosine, Dipyridamole, Chlorpromazine and Acetylsalicylic Acid

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648055 ◽

1976 ◽

Vol 36 (02) ◽

pp. 401-410 ◽

Cited By ~ 6

Author(s):

Buichi Fujttani ◽

Toshimichi Tsuboi ◽

Kazuko Takeno ◽

Kouichi Yoshida ◽

Masanao Shimizu

Keyword(s):

Guinea Pig ◽

Acetylsalicylic Acid ◽

Guinea Pigs ◽

Glass Bead ◽

Animal Species ◽

Inhibitory Effect ◽

Rabbit Platelet ◽

Platelet Adhesiveness

SummaryThe differences among human, rabbit and guinea-pig platelet adhesiveness as for inhibitions by adenosine, dipyridamole, chlorpromazine and acetylsalicylic acid are described, and the influence of measurement conditions on platelet adhesiveness is also reported. Platelet adhesiveness of human and animal species decreased with an increase of heparin concentrations and an increase of flow rate of blood passing through a glass bead column. Human and rabbit platelet adhesiveness was inhibited in vitro by adenosine, dipyridamole and chlorpromazine, but not by acetylsalicylic acid. On the other hand, guinea-pig platelet adhesiveness was inhibited by the four drugs including acetylsalicylic acid. In in vivo study, adenosine, dipyridamole and chlorpromazine inhibited platelet adhesiveness in rabbits and guinea-pigs. Acetylsalicylic acid showed the inhibitory effect in guinea-pigs, but not in rabbits.

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The Ullrastructure of Platelet Participation in Hemostasis

Thrombosis and Haemostasis ◽

10.1055/s-0038-1656288 ◽

1965 ◽

Vol 13 (01) ◽

pp. 065-083 ◽

Cited By ~ 7

Author(s):

Shirley A. Johnson ◽

Ronaldo S. Balboa ◽

Harlan J. Pederson ◽

Monica Buckley

Keyword(s):

Platelet Aggregation ◽

Red Blood Cells ◽

Blood Cells ◽

Guinea Pigs ◽

Platelet Factor ◽

Mesenteric Vessels ◽

Platelet Aggregates ◽

Electron Lucent

SummaryThe ultrastructure of platelet aggregation in vivo in response to bleeding brought about by transection of small mesenteric vessels in rats and guinea pigs has been studied. Platelets aggregate, degranulate and separating membranes disappear in parallel with fibrin appearance which is first seen at several loci after 30 seconds of bleeding. About 40 per cent of the electron opaque granules, some of which contain platelet factor 3 have disappeared after one minute of bleeding while the electron lucent granules increase by 70 per cent suggesting that some of them may be empty vesicles. Most of the platelet aggregates of the random type disappear leaving clumped red blood cells entrapped by a network of fibrin fibers which emanate from the remains of platelet aggregates of the rosette type to maintain hemostasis.

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