In vitro assessment of six aspiration catheters using a distal protection filter

Background: We assessed performance of 6 aspiration catheters for distal embolization using a distal protection filter in an in vitro experiment. In acute myocardial infarction, a distal protection filter is used for lesions likely to induce a distal embolism. Which aspiration cathether is most effective when used with a distal protection filter remains still unclear.Methods: A 0.5-cm3 bolus of gelatin as a model of stagnant pools of coronary plaque debris was captured in the distal protection filter and aspirated by 6 aspiration catheters. We measured and compared the length of the suspended embolus matter.Results: Among the 6 catheters evaluated, the use of the Export Advance catheter (Medtronic) resulted in significantly shorter lengths of the suspended embolus matter compared to the use of the TVAC II (Nipro), Thrombuster III SL (Kaneka), and Rebirth Pro (Goodman) catheters (p < 0.01). The residual embolus matter in all cases had drained distally to the distal protection filter when the filter was retrieved.Conclusions: The use of the Export Advance catheter showed better performance using a distal protection filter in this in vitro experiment, and its use might be more effective in preventing distal embolisms in combination with a distal protection filter

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Behavior of in vitro, in vivo and internal motion of micro/nano particles of titanium, titanium oxides and others

To clarify the effect of micro/nanosizing of materials onto biological organism, the particle size dependence of reaction of cells and tissue as investigated by both biochemical cell functional test and animal implantation test. Especially for nanoparticles the behavior of invasion and internal diffusion inside body was visualized using an XSAM (X-ray Scanning Analytical Microscope). The increase of specific surface area is usually counted as nanosizing effect which causes the enhancement of chemical reactivity and therefore toxicity of materials such as carcinogenicity found in 500nm Ni particles for the long term implantation in the soft tissue of rat. Even biocompatible materials such as Ti and TiO_2 shows stimulus with the decrease of particle size. They cause phagocytosis to cells and inflammation to tissue when the size of particles is below 3μm. For the size below 50nm, they may invade into the internal body through the respiratory or digestive system and diffuse inside body. After compulsory exposure test of 30nm TiO_2 particles through the respiratory system, the Ti mapping by XSAM showed the internal diffusion inside the whole body. Nanoparticles injected from caudal vein diffused with time course to lung, liver and spleen. The uptake of 30nm TiO_2 particles through the digestive system and diffusion into these organs was also confirmed. These phenomena observed in biocompatible or bioinert materials are the nonspecific, physical particle and shape effects which occur independent of materials. Nanoparticles might be the objects whose existence has not been assumed by the living body defense system

Suppressive effect of AMP-activated protein kinase on the epithelial-mesenchymal transition in retinal pigment epithelial cells.

The epithelial-mesenchymal transition (EMT) in retinal pigment epithelial (RPE) cells plays a central role in the development of proliferative vitreoretinopathy (PVR). The purpose of this study was to investigate the effect of AMP-activated protein kinase (AMPK), a key regulator of energy homeostasis, on the EMT in RPE cells. In this study, EMT-associated formation of cellular aggregates was induced by co-stimulation of cultured ARPE-19 cells with tumor necrosis factor (TNF)-α (10 ng/ml) and transforming growth factor (TGF)-β2 (5 ng/ml). 5-Aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR), a potent activator of AMPK, significantly suppressed TNF-α and TGF-β2-induced cellular aggregate formation (p < 0.01). Dipyridamole almost completely reversed the suppressive effect of AICAR, whereas 5'-amino-5'-deoxyadenosine restored aggregate formation by approximately 50%. AICAR suppressed the downregulation of E-cadherin and the upregulation of fibronectin and α-smooth muscle actin by TNF-α and TGF-β2. The levels of matrix metalloproteinase (MMP)-2, MMP-9, interleukin-6, and vascular endothelial growth factor were significantly decreased by AICAR. Activation of the mitogen-activated protein kinase and mammalian target of rapamycin pathways, but not the Smad pathway, was inhibited by AICAR. These findings indicate that AICAR suppresses the EMT in RPE cells at least partially via activation of AMPK. AMPK is a potential target molecule for the prevention and treatment of PVR, so AICAR may be a promising candidate for PVR therapy

The Inhibitory Action of Kohamaic Acid A Derivatives on Mammalian DNA Polymerase β

molecule