Interaction of amorphous calcium phosphate with fibrin in vitro causes decreased fibrinolysis and altered protease profiles: implications for atherosclerotic disease

Small organic molecules containing amorphous calcium phosphate: synthesis, characterization and transformation

As the primary solid phase, amorphous calcium phosphate (ACP) is a pivotal precursor in cellular biomineralization. The intrinsic interplay between ACP and Howard factor underscores the significance of understanding their association for advancing biomimetic ACP development. While organic compounds play established roles in biomineralization, this study presents the synthesis of ACP with naturally occurring organic compounds (ascorbate, glutamate, and itaconate) ubiquitously found in mitochondria and vital for bone remodeling and healing. The developed ACP with organic compounds was meticulously characterized using XRD, FTIR, and solid-state 13C and 31P NMR. The morphological analysis revealed the characteristic spherical morphology with particle size close to 20 nm of all synthesized ACP variants. Notably, the type of organic compound strongly influences true density, specific surface area, particle size, and transformation. The in vitro analysis was performed with MC3T3-E1 cells, indicating the highest cell viability with ACP_ASC (ascorbate), followed by ACP_ITA (itaconate). The lowest cell viability was observed with 10 %w/v of ACP_GLU (glutamate); however, 1 %w/v of ACP_GLU was cytocompatible. Further, the effect of small organic molecules on the transformation of ACP to low crystalline apatite (Ap) was examined in Milli-Q® water, PBS, and α-MEM.

Gastric cancer - The role of matrix metalloproteinases in tumor progression

Gastric cancer (GC) is a very aggressive malignant tumor of gastrointestinal tract due to its invasive nature and early metastatic ability. Degradation of the extracellular matrix (ECM) and basement membrane (BM) barriers are essential steps in the pathology of GC. Matrix metalloproteinases (MMPs) play a crucial role in the process due to their ability to degrade and rearrange these barriers to support and facilitate tumor cell migration. Therefore, these enzymes affect early carcinogenesis, tumor development and growth as well as the invasion of cancer cells at primary and metastatic sites. The endogenous inhibitors of matrix metalloproteinases (TIMPs) inhibit the active forms of MMPs and regulate the processes of their activation. The imbalance between MMPs and TIMPs may facilitate the progression of neoplastic cells. The enhanced levels of various MMPs and TIMPs have been observed in the tissue, plasma and serum of patients with many types of tumor, including gastric cancer. Moreover, levels of MMPs and TIMPs in the tissues as well as in the blood of GC patients correlated with tumor stage, depth of tumor invasion, presence of nodal and distant metastases. Selected MMPs and their tissue inhibitors were proved to be independent prognostic factors for GC patients' survival. However, further studies concerning the role of MMPs and their inhibitors in tumor biology are necessary.

Plasma matrix metalloproteinase-9 level is better than serum matrix metalloproteinase-9 level to predict gastric cancer evolution

PURPOSE

Matrix metalloproteinase-9 (MMP-9) in blood is a promising new tumor marker. The aims of the present study are to compare the usefulness of plasma and serum MMP-9 levels for predicting gastric cancer development, invasion, and survival.

EXPERIMENTAL DESIGN

In this nested case-control study, 114 gastric cancer patients and 87 healthy controls were enrolled. MMP-9 levels and activities were quantitatively measured by ELISA assay and zymography. The results were compared with the occurrence, clinicopathologic features, and outcomes of gastric cancer patients. The follow-up time for all patients was at least 5 years.

RESULTS

Serum MMP-9 levels were significantly higher than plasma MMP-9 levels. Both plasma and serum MMP-9 levels correlated significantly with active MMP-9 identified by zymography (P = 0.002 and P = 0.048, respectively). Plasma MMP-9 level was significantly elevated in gastric cancer patients when compared with control subjects (P < 0.001). Serum MMP-9 levels did not differ between the groups. Receiver-operator characteristics analysis showed the values of sensitivity (82.5%) and specificity (65.5%) at the maximum accuracy for plasma MMP-9 at >or=60 ng/mL (P < 0.001). Elevated plasma MMP-9 correlated significantly with lymph node metastasis [odds ratio (OR), 3.43; P = 0.019], lymphatic invasion (OR, 7.58; P = 0.009), and venous invasion (OR, 4.14; P = 0.033). Patients with elevated plasma MMP-9 levels had poorer survival rates than those with normal plasma MMP-9 levels (P = 0.038). Serum MMP-9 level did not correlate well with gastric cancer-invasive phenotypes or survival.

CONCLUSION

Our results suggest plasma MMP-9 level is a better marker than serum MMP-9 level for predicting gastric cancer development and progression.

Association of culprit lesion calcium with angiographic and clinical outcomes in patients with ST-elevation myocardial infarction treated with fibrinolytic therapy

Coronary artery calcium has been associated with a greater extent of angiographically significant coronary artery stenoses, but the angiographic and clinical outcomes associated with culprit lesion calcium (CLC) have not been fully evaluated, particularly in the stetting of ST-elevation myocardial infarction. We hypothesized that CLC would be associated with adverse angiographic and clinical outcomes in patients who had ST-elevation myocardial infarction. Data were evaluated in 3,292 patients from 6 trials of fibrinolytic therapy for ST-elevation myocardial infarction; 243 culprit lesions (7.4%) were calcified. CLC was associated with advanced age, history of hypertension, previous coronary artery disease, greater extent of disease, angiographically evident residual thrombus, smaller minimum luminal diameter, and larger percent residual stenosis after fibrinolytic therapy. CLC was associated with lower rates of arterial patency after fibrinolytic therapy (63.3% vs 81.3% p <0.001), lower rates of Thrombolysis In Myocardial Infarction grade 3 flow (41.5% vs 57.2%, p <0.001), and higher (slower) Thrombolysis In Myocardial Infarction frame counts (52 vs 36 frames, p <0.0001, multivariate p = 0.02). CLC was also associated with increased 30-day mortality rates (6.2% vs 3.4%, p = 0.028) and 30-day rates of death, myocardial infarction, or congestive heart failure (16.5% vs 8.9%, p <0.001) and independently associated with 30-day rates of death, myocardial infarction, or congestive heart failure (odds ratio 1.6, p = 0.016) after multivariate adjustment for baseline clinical and lesion characteristics, epicardial flow, and performance of rescue/adjunctive percutaneous coronary intervention. In a model restricted to patients who had successful restoration of epicardial patency after fibrinolytic therapy, CLC was independently associated with 30-day mortality (odds ratio 2.2, p = 0.045). CLC is independently associated with indexes of poorer epicardial flow and a higher incidence of adverse clinical outcomes after fibrinolytic administration in patients who have ST-elevation myocardial infarction.