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Objective— Toll-like receptors (TLR) bridge innate immunity and host responses, including inflammation. Sterile inflammation such as a venous thrombus (V t ) may involve TLR signaling, including TLR9. Methods and Results— TLR9 signaling on thrombus resolution was investigated using a mouse model of stasis V t . V t were significantly larger in TLR9−/− mice compared with wild-type (WT) at 2 and 8 days, despite a 2-fold increase in thrombus polymorphonucleic neutrophils at 2 days and monocytes at 8 days, whereas thrombus collagen and neovascularization was 55% and 37% less, respectively, at 8 days. Coincidently, decreased fibrinogen and increased thrombin-antithrombin complex were observed in TLR9−/− mouse thrombi. Vein wall interferon-α, interleukin-1α, and interleukin-2 were significantly reduced in TLR9−/− mice compared with WT. Thrombus cell death pathway markers were not significantly altered at 2 days, but caspase-1 was reduced in TLR9−/− thrombi at 8 days. MyD88 confers TLR9 intracellular signaling, but MyD88−/− mice had V t resolution similar to that of WT. However, inhibition of the NOTCH ligand δ-like 4 was associated with larger V t . Finally, stimulation with a TLR9 agonist was associated with smaller V t . Conclusion— TLR9 signaling is integral for early and mid-V t resolution through modulation of sterile inflammation, maintaining a TH1 milieu, and effects on the thrombosis pathway.

Regenerative peripheral nerve interfaces (RPNIs) are implantable devices for amputee communication between peripheral nerves and microprocessor controlled robotic prostheses. Our RPNIs consist of transferred muscles reinnervated by the peripheral nerves remaining in the limb post amputation. RPNI construction includes a light muscle wrap of decellularized small-intestine submucosa (SIS). We studied RPNI revascularization and regeneration when SIS had an electrically conductive coating of poly 3,4 ethylene dioxytheophene (PEDOT). Rats underwent free-muscle transfer (FMT). The peroneal nerve was divided and the proximal end was implanted in the FMT. Experimental groups received either: a) no SIS (NONE), b) SIS (SIS) wrap, or c) wrap of SIS polymerized with PEDOT, (SIS+PEDOT). One week later, rats were perfused with lead oxide, vascular areas were quantified and histology was performed. SIS+PEDOT group muscles contained less revascularization under the wrap than the SIS group, (p=.05). Histology showed that at 7 days, muscle fibers in the SIS+PEDOT group were not degenerating and regenerating similarly to those muscle fibers in the NONE and SIS groups. Images of SIS and SIS+PEDOT indicate the PEDOT filled the pores of the SIS. This reduced porosity may prohibit revascularization through the SIS+PEDOT. Data indicate that revascularization in the NONE and SIS groups are similar to control muscle while vascularity in the SIS+PEDOT group is impaired by SIS+PEDOT.

Applications combining wireframe and shaded primitives often produce unwanted artifacts and thus poor-quality polygon edging. We have developed an algorithm that uses an edging plane to generate clean, high-quality polygon edges when using separately drawn vectors to highlight polygon borders. The algorithm maintains the subpixel adjustments necessary for accurate polygonal rendering. The edging plane is simple to incorporate into existing software and hardware scan convertors. In this article, we describe the problem of edging a single polygon, then extend the discussion to multipolygon surfaces and multiple component assemblies. We introduce our algorithm and compare it to existing methods for improving polygon edges. >

SummaryDeep-vein thrombosis (DVT) resolution is thought to be primarily a urokinase plasminogen activator (uPA) -dependent mechanism, although observations suggest other non-fibrinolytic mechanisms may exist. We explored the role of matrix metalloproteinase (MMP) -2 and –9 in early DVT resolution in uPA-deficient mice. Male B6/SVEV (WT) and genetically matched uPA -/- mice underwent inferior vena cava (IVC) ligation to create stasis venous thrombi, with IVC and thrombus harvest. Thrombus size was similar between WT and uPA -/- mice at day 4, suggesting early non uPA-dependent resolution. Intrathrombus neutrophils and monocytes were reduced 3- and 3.5-fold in uPA -/- mice as compared with WT. By ELISA, tumour necrosis factor α and interleukin 1β were not altered, while interferon (IFN)γ was significantly elevated in uPA -/- mice. A compensatory increase in thrombus tPA was not observed, plasmin activity was reduced and PAI-1 was elevated 2.5-fold in uPA -/- mice. Active MMP2, but not MMP9, was elevated 3-fold in uPA-/- mice as compared with WT as well as MMP-14, an MMP2 activator. Collagen type IV and fibrinogen were reduced in uPA -/- mice thrombi as compared with WT. IFNγ induces MMP2, and blockade of IFNγ was associated with larger venous thrombi and reduced active MMP2, as compared with WT. Consistently, MMP2 -/- mice had larger VT as compared with WT controls, despite normal thrombus plasmin levels. Taken together, early experimental venous thrombus resolution is independent of uPA, and, in part, inflammatory cell influx. MMP2-dependent thrombolysis is an important compensatory mechanism of venous thrombus resolution, possibly by collagen type IV metabolism, and may represent an exploitable therapeutic avenue.

BackgroundVein wall fibrotic injury following deep venous thrombosis (VT) is associated with elevated matrix metalloproteinases (MMPs). Whether and by what mechanism MMP2 contributes to vein wall remodeling after VT is unknown.MethodsStasis VT was produced by ligation of the inferior vena cava and tissue was harvested at 2, 8, and 21 days in MMP2 -/- and genetic wild type (WT) mice. Tissue analysis by immunohistochemistry, enzyme-linked immunosorbent assay, real-time polymerase chain reaction, and zymography was performed.ResultsThrombus resolution was less at 8 days in MMP2 -/- compared with WT, evidenced by a 51% increase in VT size (P < .01), and threefold fewer von Willebrand's factor positive channels (P < .05). In MMP2 -/- mice, the main phenotypic fibrotic differences occurred at 8 days post-VT, with significantly less vein wall collagen content (P = .013), fourfold lower procollagen III gene expression (P < .01), but no difference in procollagen I compared with WT. Decreased inflammation in MMP2 -/- vein walls was suggested by ∼ threefold reduced TNFα and IL-1β at 2 days and 8 days post-VT (P < .05). A fourfold increase in vein wall monocytes (P = .03) with threefold decreased apoptosis (P