Atherosclerotic coronary artery disease (CAD) is the number one cause of death worldwide. The majority of CAD-induced deaths are due to the rupture of vulnerable plaques. Accurate assessment of plaques is crucial to optimize treatment and prevent death in patients with CAD. Current diagnostic techniques are often limited by either spatial resolution or penetration depth. Several studies have proved that the combined use of optical and ultrasonic imaging techniques increase diagnostic accuracy of vulnerable plaques. Here, we introduce an ultrafast optical-ultrasonic dual-modality imaging system and flexible miniaturized catheter, which enables the translation of this technology into clinical practice. This system can perform simultaneous optical coherence tomography (OCT)-intravascular ultrasound (IVUS) imaging at 72 frames per second safely in vivo, i.e., visualizing a 72 mm-long artery in 4 seconds. Results obtained in atherosclerotic rabbits in vivo and human coronary artery segments show that this ultrafast technique can rapidly provide volumetric mapping of plaques and clearly identify vulnerable plaques. By providing ultrafast imaging of arteries with high resolution and deep penetration depth simultaneously, this hybrid IVUS-OCT technology opens new and safe opportunities to evaluate in real-time the risk posed by plaques, detect vulnerable plaques, and optimize treatment decisions.

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SummaryPlacement of the intact omentum upon a recently traumatised spinal cord was found to be effective in lessening motor and neuroelectrical dysfunction in a group of cats. It was theorised that the beneficial effect of omental transposition was due to the establishment of a dynamic equilibrium between production of vasogenic oedema from the injured cord and its absorption through omental pathways. Removing vasogenic oedema at the omental/ spinal cord interface is hypothesised to stabilise a rising tissue pressure within the cord during the acute phase of injury and at a later date to decrease scar formation at the injury site. Key words: Spinal cord injury; Intact omental transposition; Motor and neuro electrical activity.Previous reports from our laboratory have shown that placing the intact omentum directly upon the normal and traumatized spinal cord allows for the development of blood vessels (Goldsmith et al., 1975) and the absorption of va so genic oedema fluid (Goldsmith et al., 1983) at the omental-spinal cord interface.The purpose of this study was to learn the effect of early placement of the pedicled omentum on a recently traumatised cat spinal cord as measured by subsequent motor and neuroelectrical activity of the hind limbs. Materials and methodsAdult female cats weighing 3,0-3,5 kg were used in this study. Ketalar (33 mgm/kg) was given intramuscularly for anaesthesia with additional amounts (12-25 mgm) of the agent being administered when necessary during the

The extracellular matrix of the atrioventricular (AV) valves' leaflets has a key role in the ability of these valves to properly remodel in response to constantly varying physiological loads. While the loading on mitral and tricuspid valves is significantly different, no information is available on how collagen fibers change their orientation in response to these loads. This study delineates the effect of physiological loading on AV valves' leaflets microstructures using Second Harmonic Generation (SHG) microscopy. Fresh natural porcine tricuspid and mitral valves' leaflets (n = 12/valve type) were cut and prepared for the experiments. Histology and immunohistochemistry were performed to compare the microstructural differences between the valves. The specimens were imaged live during the relaxed, loading, and unloading phases using SHG microscopy. The images were analyzed with Fourier decomposition to mathematically seek changes in collagen fiber orientation. Despite the similarities in both AV valves as seen in the histology and immunohistochemistry data, the microstructural arrangement, especially the collagen fiber distribution and orientation in the stress-free condition, were found to be different. Uniaxial loading was dependent on the arrangement of the fibers in their relaxed mode, which led the fibers to reorient in-line with the load throughout the depth of the mitral leaflet but only to reorient in-line with the load in deeper layers of the tricuspid leaflet. Biaxial loading arranged the fibers in between the two principal axes of the stresses independently from their relaxed states. Unlike previous findings, this study concludes that the AV valves' three-dimensional extracellular fiber arrangement is significantly different in their stress-free and uniaxially loaded states; however, fiber rearrangement in response to the biaxial loading remains similar.

Objectives: Minimally invasive fat sculpting techniques are becoming more widespread with the development of office-based devices and therapies. Electrochemical lipolysis (ECLL) is a needle-based technology that uses direct current (DC) to electrolyze tissue water creating acid and base in situ. In turn, fat is saponified and adipocyte cell membrane lysis occurs. The electrolysis of water can be accomplished using a simple open-loop circuit (V-ECLL) or by incorporating a feedback control circuit using a potentiostat (P-ECLL). A potentiostat utilizes an operational amplifier with negative feedback to allow users to precisely control voltage at specific electrodes. To date, the variation between the two approaches has not been studied. The aim of this study was to assess current and charge transfer variation and lipolytic effect created by the two approaches in an in vivo porcine model. Methods: Charge transfer measurements from ex vivo V-ECLL and P-ECLL treated porcine skin and fat were recorded at −1 V P-ECLL, −2 V P-ECLL, −3 V P-ECLL, and −5 V V-ECLL each for 5 min to guide dosimetry parameters for in vivo studies. In follow-up in vivo studies, a sedated female Yorkshire pig was treated with both V-ECLL and P-ECLL across the dorsal surface over a range of dosimetry parameters, including −1.5 V P-ECLL, −2.5 V P-ECLL, −3.5 V P-ECLL, and 5 V V-ECLL each treated for 5 min. Serial biopsies were performed at baseline before treatment, 1, 2, 7, 14, and 28 days after treatment. Tissue was examined using fluorescence microscopy and histology to compare the effects of the two ECLL approaches. Results: Both V-ECLL and P-ECLL treatments induced in-vivo fat necrosis evident by adipocyte membrane lysis, adipocyte denuclearization, and an acute inflammatory response across a 28-day longitudinal study. However, −1.5 V P-ECLL produced a smaller spatial necrotic effect compared to 5 V V-ECLL. In addition, 5 V V-ECLL produced a comparable necrotic effect to that of −2.5 V and −3.5 V P-ECLL. Conclusions: V-ECLL and P-ECLL at the aforementioned dosimetry parameters both achieved fat necrosis by adipocyte membrane lysis and denuclearization. The −2.5 V and −3.5 V P-ECLL treatments created spatially similar fat necrotic effects when compared to the 5 V V-ECLL treatment. Quantitatively, total charge transfer between dosimetry parameters suggests that −2.5 V P-ECLL and 5 V V-ECLL produce comparable electrochemical reactions. Such findings suggest

An increasing number of integrated optical and acoustic intravascular imaging systems have been developed and hold great promise for accurately diagnosing vulnerable plaques and guiding atherosclerosis treatment. However, in any intravascular environment, the vascular lumen is filled with blood, a high-scattering source for optical and high-frequency ultrasound signals. Blood must be flushed away to provide clearer images. To our knowledge, no research has been performed to find the ideal flushing agent for combined optical and acoustic imaging techniques. We selected three solutions as potential flushing agents for their image-enhancing effects: mannitol, dextran, and iohexol. Testing of these flushing agents was performed in a closed-loop circulation model and in vivo on rabbits. We found that a high concentration of dextran was the most useful for simultaneous intravascular ultrasound and optical coherence tomography imaging.

Efforts to extend myocardial preservation for transplantation by crystalloid perfusion have been limited by edema and compromised function. We hypothesized that hypothermic perfusion preservation with a polyethylene glycol (PEG) conjugated hemoglobin solution may extend preservation times. The purpose of this study was to compare cardiac function after continuous perfusion by using a hypocalcemic, normokalemic crystalloid perfusate with and without the addition of PEG-hemoglobin (Hb). The hearts of 20 anesthetized and ventilated New Zealand White rabbits were harvested after cold cardioplegic arrest. Group I (n = 10) hearts were continuously perfused with a hypocalcemic, normokalemic 3% bovine PEG-Hb solution at 20 degrees C and 30 mm Hg for 8 hours. Group II (n = 10) hearts were continuously perfused with an identical crystalloid solution without PEG-Hb for 8 hours under the same conditions as group I hearts. Cardiac function was measured with a left ventricular force transducer after transfer to a standard crystalloid Langendorff circuit at 37 degrees C and an aortic root pressure of 59 mm Hg. After 8 hours of perfusion preservation, heart rate was similar for groups I and II (p = not significant [NS]). Coronary blood flow after and during preservation was similar between PEG-Hb and crystalloid preserved hearts (p = NS). Left ventricular developed pressure, peak dP/dt, and peak -dP/dt were superior in hearts preserved with PEG-Hb. Percent water of total ventricular weight was 82.0% for group I and 81.6% for group II (p = NS). Continuous perfusion preservation of rabbit hearts for 8 hours with a hypocalcemic normokalemic PEG-Hb based solution at 30 mm Hg and 20 degrees C yields left ventricular function that is superior to perfusion with a similar crystalloid solution without PEG-Hb, despite similar myocardial edema and coronary flow. Extended cardiac perfusion preservation with this PEG-Hb based solution deserves further study, including comparison with traditional cardioplegic preservation solutions.

This study demonstrates the ability of pravastatin to inhibit chronic rejection in rat renal allografts. Pravastatin's pleiotropic effects of reducing intragraft inflammatory cytokines, inhibiting immune cell infiltration, and causing up-regulation of the antiapoptotic gene Bag-1 suggest that its ability to prevent transplant chronic rejection may be multifactorial.