Porous calcium polyphosphate scaffolds for bone substitute applications in vivo studies

This study aimed to explore the surface modification of deproteinized bovine bone using lithium-ion and evaluate its efficacy on osteogenesis improvement and critical-sized bone defect repair. Hydrothermal treatment was performed to produce lithium-incorporated deproteinized bovine bone. In vitro study, human osteosarcoma cell MG63 (MG63) was cultured with the bone substitute to evaluate the cell viability and then calcium deposition was measured to analyze the osteogenesis. In vivo studies, male adult goats were chosen to build critical-sized bone defect model and randomly divided into three groups. The goats were treated with autogenous cancellous bone, lithium-incorporated deproteinized bovine bone, and deproteinized bovine bone. Animals were evaluated using radiological analysis including X-ray, computed tomography, and Micro-CT; histological methods involving hematoxylin–eosin dyeing, Masson dyeing, and immunofluorescence detection at 4 and 12 weeks after surgery were carried out. According to the results, lithium-incorporated deproteinized bovine bone produced nano-structured surface layer. The lithium-incorporated deproteinized bovine bone could promote the osteoblast proliferation and increase the calcium deposition. In vivo studies, radiographic results revealed that lithium-incorporated deproteinized bovine bone scaffolds provided better performance in terms of mean gray values of X films, mean pixel values of computed tomography films, and bone volume and trabecular thickness of micro-computed tomography pictures when compared with the deproteinized bovine bone group. In addition, histological analysis showed that the lithium-incorporated deproteinized bovine bone group also significantly achieved larger new bone formation area. At the same time, when the expression of osteogenic factors in vivo was evaluated, runt-related transcription factor 2 (Runx2) and collagen type one (Col-1) were expressed more in lithium-incorporated deproteinized bovine bone group than those in deproteinized bovine bone group. However, the bone defect repair effect using autograft is still a little better than that of lithium-incorporated deproteinized bovine bone substitute based on our results. In conclusion, surface lithium-incorporated deproteinized bovine bone achieved improvement of osteogenesis effect and could enhance the new bone formation in critical-sized bone defects.

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Regulation of vascular endothelial growth factor expression in human endometrium by steroids and hypoxia: In vitro and in vivo studies

Journal of the Society for Gynecologic Investigation ◽

10.1016/s1071-5576(97)86195-3 ◽

1998 ◽

Vol 5 (1) ◽

pp. 69A-69A

Author(s):

A SHARKEY ◽

D CHARNOCKJONES ◽

K DAY ◽

H SOWTER ◽

L SVENSSON ◽

...

Keyword(s):

Vascular Endothelial Growth Factor ◽

Growth Factor ◽

Human Endometrium ◽

In Vivo Studies ◽

Vascular Endothelial ◽

Factor Expression ◽

Growth Factor Expression ◽

Endothelial Growth Factor

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In vitro and in vivo studies of new cationic Zn(II)‐benzonaphthoporphyrazines as photosensitizers for PDT

Journal of Porphyrins and Phthalocyanines ◽

10.1002/jpp.373.abs ◽

2001 ◽

Vol 5 (8) ◽

pp. 645-651

Author(s):

M. Peeva ◽

M. Shopova ◽

U. Michelsen ◽

D. Wöhrle ◽

G. Petrov ◽

...

Keyword(s):

In Vivo Studies

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Effect of caffeine on theophyliine on cerebral blood flow response to brain activation: In vitro and in vivo studies

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/sj.jcbfm.9591524.0198 ◽

2005 ◽

Vol 25 (1_suppl) ◽

pp. S198-S198

Author(s):

Joseph R Meno ◽

Thien-son K Nguyen ◽

Elise M Jensen ◽

G Alexander West ◽

Leonid Groysman ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Brain Activation ◽

In Vivo Studies ◽

Blood Flow Response ◽

Flow Response

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Effects of Unfractionated and Low Molecular Weight Heparins on Platelet Thromboxane Biosynthesis “In Vivo”

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648988 ◽

1994 ◽

Vol 72 (06) ◽

pp. 942-946 ◽

Cited By ~ 20

Author(s):

Raffaele Landolfi ◽

Erica De Candia ◽

Bianca Rocca ◽

Giovanni Ciabattoni ◽

Armando Antinori ◽

...

Keyword(s):

Molecular Weight ◽

Unfractionated Heparin ◽

Low Molecular Weight Heparin ◽

Primary Source ◽

In Vivo Studies ◽

Low Molecular Weight ◽

Heparin Administration ◽

To Receive

SummarySeveral “in vitro” and “in vivo” studies indicate that heparin administration may affect platelet function. In this study we investigated the effects of prophylactic heparin on thromboxane (Tx)A2 biosynthesis “in vivo”, as assessed by the urinary excretion of major enzymatic metabolites 11-dehydro-TxB2 and 2,3-dinor-TxB2. Twenty-four patients who were candidates for cholecystectomy because of uncomplicated lithiasis were randomly assigned to receive placebo, unfractionated heparin, low molecular weight heparin or unfractionaed heparin plus 100 mg aspirin. Measurements of daily excretion of Tx metabolites were performed before and during the treatment. In the groups assigned to placebo and to low molecular weight heparin there was no statistically significant modification of Tx metabolite excretion while patients receiving unfractionated heparin had a significant increase of both metabolites (11-dehydro-TxB2: 3844 ± 1388 vs 2092 ±777, p <0.05; 2,3-dinor-TxB2: 2737 ± 808 vs 1535 ± 771 pg/mg creatinine, p <0.05). In patients randomized to receive low-dose aspirin plus unfractionated heparin the excretion of the two metabolites was largely suppressed thus suggesting that platelets are the primary source of enhanced thromboxane biosynthesis associated with heparin administration. These data indicate that unfractionated heparin causes platelet activation “in vivo” and suggest that the use of low molecular weight heparin may avoid this complication.

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Ex Vivo Inhibition of Platelet Aggregation in Patients with Severe Limb Arteriopathy Treated with BAY U3405, a Specific IX A2 Receptor Antagonist

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648937 ◽

1994 ◽

Vol 72 (05) ◽

pp. 659-662 ◽

Cited By ~ 1

Author(s):

S Bellucci ◽

W Kedra ◽

H Groussin ◽

N Jaillet ◽

P Molho-Sabatier ◽

...

Keyword(s):

Platelet Aggregation ◽

Ex Vivo ◽

Randomized Study ◽

In Vivo Studies ◽

Walking Distance ◽

Peripheral Blood Flow ◽

Walking Ability ◽

Double Blind ◽

Platelet Factor

SummaryA double-blind, placebo-controlled randomized study with BAY U3405, a specific thromboxane A2 (TX A2) receptor blocker, was performed in patients suffering from severe stade II limb arteriopathy. BAY U3405 or placebo was administered in 16 patients at 20 mg four times a day (from day 1 to day 3). Hemostatic studies were done before therapy, and on day 2 and day 3 under therapy. On day 3, BAY U3405 was shown to induce a highly statistically significant decrease of the velocity and the intensity of the aggregations mediated by arachidonic acid (56 ± 37% for the velocity, 58 ± 26% for the intensity) or by U46619 endoperoxide analogue (36 ± 35% for the velocity, 37 ± 27% for the intensity). Similar results were already observed on day 2. By contrast, such a decrease was not noticed with ADP mediated platelet aggregation. Furthermore, plasma levels of betathrombo-globulin and platelet factor 4 remained unchanged. Peripheral hemodynamic parameters were also studied. The peripheral blood flow was measured using a Doppler ultrasound; the pain free walking distance and the total walking ability distance were determined under standardized conditions on a treadmill. These last two parameters show a trend to improvement which nevertheless was not statistically significant. All together these results encourage further in vivo studies using BAY U3405 or related compounds on a long-term administration.

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Inactivation of Factor XIa in Vivo: Studies in Chimpanzees and in Humans

Thrombosis and Haemostasis ◽

10.1055/s-0038-1650621 ◽

1996 ◽

Vol 76 (04) ◽

pp. 549-555 ◽

Cited By ~ 16

Author(s):

Walter A Wuillemin ◽

C Erik Hack ◽

Wim K Bleeker ◽

Bart J Biemond ◽

Marcel Levi ◽

...

Keyword(s):

Antithrombin Iii ◽

Life Time ◽

In Vivo Studies ◽

Clinical Samples ◽

Plasma Samples ◽

C1 Inhibitor ◽

Elimination Kinetics ◽

Factor Xia ◽

Best Parameter

SummaryC1-inhibitor (C1Inh), antithrombin III (ATIII), α1-antitrypsin (a1AT), and α2-antiplasmin (a2AP) are known inhibitors of factor XIa (FXIa). However, their precise contribution to FXIa inactivation in vivo is not known. We investigated FXIa inactivation in chimpanzees and assessed the contribution of these inhibitors to FXIa inactivation in patients with presumed FXI activation.Chimpanzees were infused with FXIa and the various FXIa-FXIa inhibitor complexes formed were measured. Most of FXIa was complexed to C1Inh (68%), followed by a2AP (13%), a1AT (10%), and ATIII (9%). Analysis of the plasma elimination kinetics revealed a half-life time of clearance (t1/2) for the FXIa-FXIa inhibitor complexes of 95 to 104 min, except for FXIa-a1AT, which had a t1/2 of 349 min. Due to this long t1/2, FXIa-a1AT complexes were predicted to show the highest levels in plasma samples from patients with activation of FXI. This was indeed shown in patients with disseminated intravascular coagulation, recent myocardial infarction or unstable angina pectoris. We conclude from this study that in vivo C1Inh is the predominant inhibitor of FXIa, but that FXIa-a1 AT complexes due to their relatively long t1/2 may be the best parameter to assess FXI activation in clinical samples.

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Effects of Ellagic Acid upon the Rabbit Fibrinolytic System

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649010 ◽

1972 ◽

Vol 27 (01) ◽

pp. 063-071

Author(s):

S. G Iatridis ◽

P. G Iatridis

Keyword(s):

Continuous Infusion ◽

Ellagic Acid ◽

Animal Experimentation ◽

Inhibitory Effect ◽

In Vivo Studies ◽

Clot Lysis ◽

Hageman Factor ◽

Lysis Activity ◽

Site Of Action

SummaryThe present investigation deals with in vivo studies of possible relations of active Hageman factor (HFa) to the problems of thrombolysis. The study is based upon animal experimentation in which 40 normal, 5 dicumarolized and 5 heparinized rabbits each received ellagic acid (Elac 10-2 M) by intravenous continuous infusion at a rate of 1 ml/min for a period of 25 min. The data suggest that the Elac infusion induced in vivo activation of HF. Streptokinase (SK) injection 25 min from the start of Elac i. v. infusion failed to induce clot lysis in blood drawn one min after its injection. The phenomenon was more prominent with low (SK 250 U or 500 U) concentrations of SK. With higher concentrations, SK-induced clot lysis activity was not affected by Elac infusion.In dicumarolized and heparinized rabbits Elac infusion still counteracted the fibrinolysis activating effect of low concentration of SK. The possibility that the above described phenomenon was due to either hypercoagulability or to a non-specific inhibitory effect of Elac upon SK was explored and excluded.It is concluded that HFa and SK have the same site of action. Thus it seems that HFa may block the precursor upon which SK acts by forming a complex with it. It is stressed that activation of this precursor by HFa requires a suitable surface.

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