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The Lachman test is considered to be a reliable physical examination for anterior cruciate ligament (ACL) injury. Patients with a damaged ACL demonstrate a soft endpoint feeling. However, examiners judge the soft and hard endpoints subjectively. The purpose of our study was to confirm objective performance of the Lachman test using joint auscultation. Human and porcine knee joints were examined. Knee joint sound during the Lachman test (Lachman sound) was analyzed by fast Fourier transformation. As quantitative indices of Lachman sound, the peak sound as the maximum relative amplitude (acoustic pressure) and its frequency were used. The mean Lachman peak sound for healthy volunteer knees was 86.9 ± 12.9 Hz in frequency and -40 ± 2.5 dB in acoustic pressure. The mean Lachman peak sound for intact porcine knees was 84.1 ± 9.4 Hz and -40.5 ± 1.7 dB. Porcine knees with ACL deficiency had a soft endpoint feeling during the Lachman test. The Lachman peak sounds of porcine knees with ACL deficiency were dispersed into four distinct groups, with center frequencies of around 40, 160, 450, and 1600. The Lachman peak sound was capable of assessing soft and hard endpoints of the Lachman test objectively. [ABSTRACT FROM AUTHOR]

In this paper we report a perfusion culture microchamber array chip with a serial dilution microfluidic network for analyzing drug dose response over a concentration range spanning 6 orders of magnitude, which is required for practical drug discovery applications. The microchamber array chip was equipped with a pressure-driven interface, in which medium and drug solution were added with a micropipet and delivered into the microfluidic network by pneumatic pressure. We demonstrated that the microchamber array chip could be used to estimate the 50% growth inhibitory concentration using the model anticancer drug paclitaxel and the model cancer cell line HeLa. The results obtained by using the microchamber array chip were consistent with those obtained by a conventional assay using microplates. The microchamber array chip, with its simple interface and well-designed microfluidic network, has potential as an efficient platform for high-throughput dose response assays in drug discovery applications. [ABSTRACT FROM AUTHOR]

Abstract Background  An autograft of cultured bone marrow-derived mesenchymal stem cells has already been used in clinical practice. In those patients whose bone marrow cannot be used, a cell allograft with the use of immunosuppressant drugs will be an option in the future. However, little is known about the effects of immunosuppressant drugs on mesenchymal stem cells. This study assessed the effects of immunosuppressant drugs on osteogenic differentiation of mesenchymal stem cells and analyzed the manner in which immunosuppressant drugs modulate the osteogenic effect of dexamethasone. Methods  Rat bone marrow cells were cultured with or without dexamethasone as an osteogenic supplement. In each experimental group, one of three immunosuppressants (rapamycin, cyclosporine A, or FK506) was added. As a control, cells were cultured without immunosuppressants. Histologically, mineralization was assessed by alizarin red S staining and phase-contrast microscopy. Biochemically, alkaline phosphatase activity, calcium content, and osteocalcin content were assessed. Results  On histological analysis, no mineralized nodules were seen on alizarin red S staining or phase-contrast microscopy in the groups not treated with dexamethasone, except in the group that was treated with FK506. Mineralized nodules were seen in the groups treated with dexamethasone, except in the group that was treated with rapamycin. On biochemical analysis, it was found that, compared to the control group, rapamycin reduced alkaline phosphatase activity and the calcium content of mesenchymal stem cells; FK506 increased alkaline phosphatase activity, calcium content, and osteocalcin content; and cyclosporine A had negligible effects. Dexamethasone increased alkaline phosphatase activity, calcium content, and osteocalcin content, but these effects were decreased by rapamycin. Conclusions  Rapamycin did not have an osteogenic effect on mesenchymal stem cells, but inhibited the effect of osteogenic differentiation induced by dexamethasone. In contrast, FK506 had an osteogenic effect on mesenchymal stem cells. Therefore, FK506 might be more useful than rapamycin in allogeneic transplantation of mesenchymal stem cells. [ABSTRACT FROM AUTHOR]

Although numerous studies have been performed to determine whether there are histologic, biochemical, biomechanical, and metabolic differences between knee and ankle cartilage, none have investigated the presence of such differences in living human cartilage. We previously developed an ultrasonic evaluation system for articular cartilage that analyzes the A‐mode echogram using wavelet transformation. The current study was undertaken to determine whether the acoustic properties of living human cartilage differ between knee and ankle joints.Twenty‐eight patients were subjected to ultrasonic evaluation under arthroscopy. After arthroscopic grading, the cartilage was measured using an ultrasonic probe. Two quantitative parameters were used, i.e., the maximum magnitude and the echo duration at the 95% interval of the maximum magnitude.In intact cartilage, the maximum magnitude and echo duration did not differ between the knee and the ankle. In lesional cartilage, in contrast, the maximum magnitude was higher, and the echo duration was shorter, in the ankle than in the knee. These differences were statistically significant.Ultrasound findings could be used to judge the degree of early cartilage degeneration in vivo on the basis of objective data such as the maximum magnitude and echo duration. Because we were unable to quantitatively analyze the biochemical and biomechanical properties of the cartilage in this study, our biochemical and biomechanical findings are based only on qualitative assessment. Nevertheless, the results indicate that this ultrasonic evaluation system may be useful for elucidating the processes of articular cartilage degeneration in osteoarthritis. [ABSTRACT FROM AUTHOR]

Abstract  A 61-year-old woman who had undergone surgery for a right ventricular myxoma 19 years earlier was admitted to our hospital for treatment of a saccular aneurysm of the ascending aorta at the site of the previous aortic cannulation. We resected the aneurysm completely and closed it with a polyester patch. Pathologic examination revealed an aortic wall saccular aneurysm, without atherosclerotic changes or bacterial cultures, consisting of elastic fibrous tissue and artificial material. There were inflammatory changes at the top of the aneurysm, with continuity of medial elastic fibrous tissue inside. These pathological findings strongly suggested a true aneurysm with continuity of medial elastic fibrous tissue. We report this extremely unusual case of a saccular true aneurysm at a previous aortic cannulation site. [ABSTRACT FROM AUTHOR]

Novel on-chip fluid control strategies, on-demand formation of arbitrary microchannels and parallel control of multiple microvalves were successfully demonstrated by means of computer-controlled micropatterned light irradiation of a photoresponsive hydrogel sheet. [ABSTRACT FROM AUTHOR]