Magnesium-aluminum-chloride-layered double hydroxides (MgAl-Cl-LDHs) intercalated with low molecular weight heparin (LMWH) were prepared for the first time by the coprecipitation method and then characterized by XRD, elemental analysis, FTIR, SEM, and TEM. MgAl-LDH was studied as the drug carrier for LMWH, a widely used anticoagulant, in order to overcome some of its pharmaceutical limitations, such as its short half-life. In vitro release tests of LMWH-LDH in pH 7.4 PBS at 37 °C show a biphasic and sustained profile of LMWH anion release with ∼20% in the first 12 h and another ∼20% in the following 108 h. After release, the residue was characterized and dissolution−diffusion kinetic models fitted. The mechanism of MgAl-LMWH-LDH release is probably due to surface diffusion and bulk diffusion via anionic exchange of LMWH anions on or in the LDH with anions in the PBS solution.

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Peritoneal and pleural cavities of large animals can function as bioreactors to grow myofibroblast tubes for use as autologous vascular grafts.

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The complement C5a receptor, CD88, is present on many of the cells found within human atherosclerotic plaques, but little is known about the role of C5a in atherogenesis. Using real-time PCR, we determined that ApoE(-/-) mice fed a normal diet express more aortic CD88 mRNA compared with controls, and this increase coincides with atherosclerotic lesion development (P<0.001 for 3- vs. 25-wk-old animals). Conversely, mRNA expression of the alternative C5a receptor, C5L2, in aortas of ApoE(-/-) mice, was lower than controls at all time points. Using immunohistochemistry, we confirmed the presence of CD88 on macrophages, smooth muscle cells, and activated endothelial cells in plaques from brachiocephalic arteries. Treatment of ApoE(-/-) mice with a CD88 antagonist (PMX53; 3 mg/kg s.c. 3 ×/wk plus 1 mg/kg/d p.o.) for 25 wk reduced lesion size and lipid content in the plaque by ∼ 40% (P<0.05). Our study provides evidence for a proatherogenic role for C5a and identifies the CD88 antagonist PMX53 as a potential antiatherosclerotic drug.

Science can move ahead by questioning established or canonical views and, so it may be with the enzymes, nitric oxide synthases (NOS). Nitric oxide (NO) is generated by NOS isoforms that are often described by their tissue-specific expression patterns. NOS1 (nNOS) is abundant in neural tissue, NOS2 is upregulated in activated macrophages and known as inducible NOS (iNOS), and NOS3 (eNOS) is abundant in endothelium where it regulates vascular tone. These isoforms are described as constitutive or inducible, but in this perspective we question the broad application of these labels. Are there instances where “constitutive” NOS (NOS1 and NOS3) are inducibly expressed; conversely, are there instances where NOS2 is constitutively expressed? NOS1 and NOS3 inducibility may be linked to post-translational regulation, making their actual patterns activity much more difficult to detect. Constitutive NOS2 expression has been observed in several tissues, especially the human pulmonary epithelium where it may regulate airway tone. These data suggest that expression of the three NOS enzymes may include non-established patterns. Such information should be useful in designing strategies to modulate these important enzymes in different disease states.

Objective-Conversion of macrophages to foam cells is a critical step in the initiation and progression of atherosclerosis.We