ABSTRACT
Calcium polyphosphate (CPP) is a new type of degradable material for bone repair, yet it is fragile and is not so controllable in regard to degradation. For increasing biological activity and close proximity to natural bone structure, in this experiment, we chose chitosan (CS) and its derivative carboxymethyl chitosan (CMC) as the extracellular matrix structure for the organic phase. Aldehyde sodium alginate (ADA) was used as natural cross-linker. The binary (CPP/CMC) and ternary (CPP/CMC/CS) composite scaffolds were prepared by the "multiple composite-cross-linking method". The degradation laws of the two materials were investigated through the weight loss of scaffolds, the pH value of degradation solution, the compressive strength and the surface morphology characterization. The results showed that the composite scaffolds had good interface and the compressive strength increased greatly, but the organic phase of dual-phase composite scaffolds degraded quickly, while degradation controllability and mechanical properties of ternary composite scaffold were significantly improved. All the above findings show that the method of ternary complex scaffold preparation is useful for the design and preparation of bone tissue engineering materials.
Subject(s)
Humans , Absorbable Implants , Biocompatible Materials , Chemistry , Bone Cements , Chemistry , Calcium Phosphates , Chemistry , Chitosan , Chemistry , Tissue Engineering , Tissue Scaffolds , ChemistryABSTRACT
<p><b>OBJECTIVE</b>To explore the effect of plasma cross-linked D-dimer (XDP) and neuron-specific enolase (NSE) on the infarct volume and neurological function deficit in patients with cerebral infarction (CI).</p><p><b>METHODS</b>Plasma XDP and NSE levels were measured in 66 CI patients on the different days after onset and also in 46 normal individuals, and the changes in XDP and NSE levels were analyzed in the CI patients with different infarct volume and neurological function deficit scores.</p><p><b>RESULTS</b>Within 48 h following CI onset, plasma XDP and NSE levels increased significantly (P<0.01) and reached the highest levels on day 5 (P<0.001), recovering the normal level till day 18. Plasma XDP and NSE levels were significantly higher in patients with moderate to large infarct volume and in those with moderate to severe neurological deficits than in those with small infarct volume and mild neurological deficits (P<0.001).</p><p><b>CONCLUSION</b>Increment of XDP and NSE levels is an important pathological process in CI in close relation to the infarct volume and neurological deficits. XDP and NSE may serve as reliable indices for early diagnosis and evaluation of CI.</p>
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Biomarkers , Cerebral Infarction , Blood , Pathology , Cross-Linking Reagents , Chemistry , Fibrin Fibrinogen Degradation Products , Chemistry , Metabolism , Phosphopyruvate Hydratase , BloodABSTRACT
<p><b>OBJECTIVE</b>To study the changes of advanced glycation end products (AGEs) in different phases of a rat liver fibrosis model induced by CCl4, and the interventional effect of aminoguanidin (AG).</p><p><b>METHODS</b>Fifty-four SD rats were divided into three groups: a control group, a CCl4 model group and an intervention group. Their blood serum AGEs and hyaluronic acid (HA) and AGEs in their liver homogenates were measured. These measurements were correlatively assessed to the degrees of liver fibrosis at different phases of the rat model before and after the intervention with aminoguanidin.</p><p><b>RESULTS</b>The content of AGEs in their blood sera and liver homogenates, and the level of blood serum HA, and the score of liver fibrosis degree at week 12 in our rat liver fibrosis mode groups were significantly higher than those in the control group (P < 0.01). In the intervention group with aminoguanidin, these figures were lower than those in the liver fibrosis model group (P < 0.05). The content of AGEs in their blood sera and liver homogenates had a linear correlation with the level of HA in their blood sera.</p><p><b>CONCLUSION</b>The contents of AGEs in their blood sera and liver homogenates were increased in the late phase of our rat liver fibrosis model. To some extent, the level of AGEs may reflect the fibrosis degree of the rat livers. Aminoguanidin has an interventional effect in our CCl4 induced rat liver fibrosis model.</p>
Subject(s)
Animals , Male , Rats , Carbon Tetrachloride , Carbon Tetrachloride Poisoning , Glycation End Products, Advanced , Metabolism , Guanidines , Therapeutic Uses , Liver , Metabolism , Pathology , Liver Cirrhosis, Experimental , Drug Therapy , Metabolism , Rats, Sprague-DawleyABSTRACT
<p><b>OBJECTIVE</b>To observe the differentiation of bone marrow stem cells in rat hepatic fibrogenesis environment into hepatocytes.</p><p><b>METHODS</b>Rat hepatic fibrosis was induced by subcutaneous injection of CCl4. Bone marrow stem cells with Thy positive, CD3 and CD45RA negative were enriched from the bone marrow by fluorescence-activated cell sorting. The bone marrow stem cells were labeled with PKH26-GL, and then autotransplanted. After six weeks, albumin, ck8 and a-smooth muscle actin expression were determined by immunocytochemistry.</p><p><b>RESULTS</b>The PKH26-GL labeled cells expressed albumin and ck8, but did not express a-smooth muscle actin in hepatic fibrogenesis environment.</p><p><b>CONCLUSION</b>Bone marrow stem cells in hepatic fibrogenesis environment can differentiate into hepatocytes, but can't differentiate into myofibroblasts</p>