P569Diastolic dyssynchrony is associated with exercise intolerance in hypertensive patients with left ventricular hypertrophy.

BACKGROUND: Left ventricular hypertrophy (LVH) is associated with intra-ventricular dyssynchrony at systolic phase during exercise in hypertensive patients. However, dypsnea on exertion is much more correlated with diastolic phase. We investigated whether LVH is associated with diastolic dyssynchrony during exercise in patients with hypertension. METHODS: Ninety hypertensive patients with exertional dyspnea and 30 control individuals were enrolled. Exercise stress echocardiography was performed using a symptom limited, multistage supine bicycle test. To evaluate the diastolic dyssynchrony of LV, we calculated the standard deviation (SD) of the averaged time from Q wave to myocardial early diastolic velocity in 12 segments. (TPe-SD, ms). Therefore, diastolic dyssynchrony index was SD of TPe. And also, we applied modified SD (SD/heart rate). RESULTS: There was no significant difference in systolic blood pressure (BP) and heart rate between the two groups. TPe-SD was significantly higher in patients with LVH at rest (27 ± 11.0 vs. 18.7 ± 7.4 ms, p<0.005) with exaggeration of the degree at peak exercise (42.0 ± 10.6 vs. 30.6 ± 12.4 ms, p<0.001). When applying modified SD, the difference is much more increased (80.0 ± 17.6 vs. 49.0 ± 21.3 ms, p <0.001). Multiple regression analysis showed LV mass index (ß=0.515, P=0.001) and E/E' at peak exercise (ß= -0.253, P=0.025) were independently associated with LV dyssynchrony during diastolic phase when controlled for age, sex, and systolic BP at peak exercise. CONCLUSION: Intra-ventricular diastolic dyssynchrony during exercise is significantly associated with exercise duration in hypertensive patients with LVH. And this result could explain that the patients with exertional dyspnea are more common in LVH group.Univariate and multivariate analysis forUnivariate AnalysisMultivariate Analysisßp valueßp valueAge-0.288*0.037-0.355*0.001Sex0.161*0.0200.250*0.034LVMI (g/m2)-0.787*0.008-0.515*0.001LAVI(mL)-0.4400.065-0.1750.075E' at peak ex.0.2160.589Diastolic dyssynchrony-0.725*0.030-0.253*0.025S' at peak ex.0.7100.073 LVMI, left ventricular mass index; LAVI, left atrium volume index; E, early diastolic mitral inflow velocity; E', early diastolic longitudinal tissue velocity; S', early systolic longitudinal tissue velocity.Univariate and multivariate analysis for.LVMI, left ventricular mass index; LAVI, left atrium volume index; E, early diastolic mitral inflow velocity; E', early diastolic longitudinal tissue velocity; S', early systolic longitudinal tissue velocity.

Inhibition of pulmonary cancer progression by epidermal growth factor receptor-targeted transfection with Bcl-2 and survivin siRNAs.

Clinical application of small interfering RNA (siRNA) in cancer therapy has been limited by the lack of an efficient systemic siRNA delivery system. In this report we describe an efficient siRNA delivery system directed to metastasized tumors, especially in the lungs. Anticancer siRNA was condensed in the presence of 9-arginine peptides (9Arg) and then complexed with cationic O,O'-dimyristyl-N-lysyl glutamate liposomes conjugated to antibodies against the epidermal growth factor receptor (EGFR). The ternary complex of optimized anti-EGFR-9Arg-lipoplexes exhibited efficient siRNA transfection of LS174T-Luc cancer cells grown in culture or orthotopically in mouse lungs. Anti-tumor Bcl-2/survivin siRNAs loaded in the anti-EGFR-9Arg-lipoplexes effectively suppressed transcription of their target genes, resulting in an efficient cancer cell death. Repeated intravenous administrations of the anti-EGFR-9Arg-lipoplexes effectively inhibited tumor growth in the mouse lungs and prolonged survival of the mice compared with nontargeted lipoplexes. These results suggest that the ternary complexes of anti-EGFR-9Arg-lipoplexes might have clinical applications in RNA interference cancer therapy.

Lactobacillus pentosus var. plantarum C29 protects scopolamine-induced memory deficit in mice.

AIMS: In the preliminary study, kimchi, a traditional food fermented with Chinese cabbage, protected scopolamine-induced mouse memory deficit in passive avoidance test. Therefore, we screened protective ingredients, particularly lactic acid bacteria, from Chinese cabbage kimchi against scopolamine-induced memory deficit in mice. METHODS AND RESULTS: Lactic acid bacteria, isolated from Chinese cabbage kimchi, were identified by 16S rDNA sequence analysis, G+C content and cellular fatty acid composition and sugar fermentation test. Memory deficit was induced in mice by intraperitoneally injecting with scopolamine. Kimchi, particularly its supernatant, protected scopolamine-induced memory deficit in mice in passive avoidance test. Of kimchi ingredients, a lactic acid bacterium, strain C29, potently protected scopolamine-induced memory deficit in mice. C29 was a gram-positive, catalase-negative, anaerobic and non-motile rod. Its pylogenetic property was near to Lactobacillus pentosus (99%) and Lact. plantarum (99%). However, C29 fermented inulin and L-rhamnose and grew in pH 3 and at 45°C in contrast with Lact. pentosus and Lact. plantarum. Therefore, it named to be Lact pentosus var. plantarum C29. The strain C29 protected scopolamine-induced memory deficit in Y-maze and Morris water maze tests. Furthermore, C29 increased hippocampal BDNF and p-CREB expressions, which were reduced by scopolamine. CONCLUSION: Lactobacillus pentosus var. plantarum C29 may protect memory deficit by inducing BDNF and p-CREB expressions. SIGNIFICANCE AND IMPACT OF THE STUDY: Lactic acid bacteria, such as Lact pentosus var. plantarum C29, may prevent memory deficit and its contained fermented foods may be beneficial for dementia.

The effect of gadoxetic acid enhancement on lesion detection and characterisation using T2 weighted imaging and diffusion weighted imaging of the liver.

OBJECTIVES: To evaluate the effect of gadoxetic acid enhancement on the detection and characterisation of focal hepatic lesions on T(2) weighted and diffusion weighted (DW) images. METHODS: A total of 63 consecutive patients underwent T(2) weighted and DW imaging before and after gadoxetic acid enhancement. Two blinded readers independently identified all of the focal lesions using a five-point confidence scale and characterised each lesion using a three-point scale: 1, non-solid; 2, indeterminate; and 3, solid. For both T(2) weighted and DW imaging, the accuracies for detecting focal lesions were compared using the free-response receiver operating characteristic analysis; the accuracies for lesion characterisation were compared using the McNemar test between non-enhanced and gadoxetic acid-enhanced image sets. For hepatic lesions ≥ 1 cm, the lesion-to-liver contrast-to-noise ratio (CNR) and the apparent diffusion coefficient (ADC) were compared in the non-enhanced and enhanced image sets using the generalised estimating equations. RESULTS: For both T(2) weighted and DW images, the accuracies for detecting focal lesions (p ≥ 0.52) and those for lesion characterisation (p ≥ 0.63) did not differ significantly between the non-enhanced and enhanced image sets. The lesion-to-liver CNR was significantly higher on enhanced DW images than on non-enhanced DW images (p=0.02), although the difference was not significant for T(2) weighted imaging (p=0.65). The mean ADC values of lesions did not differ significantly on enhanced and non-enhanced DW imaging (p=0.75). CONCLUSION: The acquisition of T(2) weighted and DW images after administration of gadoxetic acid has no significant effect on the detection or characterisation of focal hepatic lesions, although it improves the lesion-to-liver CNR on DW images.

Induction of bone formation by Escherichia coli-expressed recombinant human bone morphogenetic protein-2 using block-type macroporous biphasic calcium phosphate in orthotopic and ectopic rat models.

BACKGROUND AND OBJECTIVE: The potential of the Escherichia coli-expressed recombinant human bone morphogenetic protein-2 (ErhBMP-2) to support new bone formation/maturation using a block-type of macroporous biphasic calcium phosphate (bMBCP) carrier was evaluated in an orthotopic and ectopic rat model. MATERIAL AND METHODS: Critical-size (Φ 8 mm) calvarial defects and subcutaneous pockets in 32 Sprague-Dawley rats received implants of rhBMP-2 (2.5 µg) in a bMBCP carrier or bMBCP alone (control). Implant sites were evaluated using histological and histometric analysis following 2- and 8-wk healing intervals (eight animals/group/interval). RESULTS: ErhBMP-2/bMBCP supported significantly greater bone formation at 2 and 8 wk (10.8% and 25.4%, respectively) than the control at 2 and 8 wk (5.3% and 14.0%, respectively) in calvarial defects (p < 0.01). Bone formation was only observed for the ErhBMP-2/bMBCP ectopic sites and was significantly greater at 8 wk (7.5%) than at 2 wk (4.5%) (p < 0.01). Appositional and endochondral bone formation was usually associated with a significant increase in fatty marrow at 8 wk. The bMBCP carrier showed no evidence of bioresorption. CONCLUSION: ErhBMP-2/bMBCP induced significant bone formation in both calvarial and ectopic sites. Further study appears to be required to evaluate the relevance of the bMBCP carrier.

Enhanced adipogenic differentiation and reduced collagen synthesis induced by human periodontal ligament stem cells might underlie the negative effect of recombinant human bone morphogenetic protein-2 on periodontal regeneration.

BACKGROUND AND OBJECTIVE: Recombinant human bone morphogenetic protein-2 (rhBMP-2) is a potent inducer for the regeneration of mineralized tissue, but has a limited effect on the regeneration of cementum and periodontal ligament (PDL). The aim of the present study was to determine the effects of rhBMP-2 on the in vitro and in vivo biologic activity of well-characterized human PDL stem cells (hPDLSCs) and to elucidate the underlying mechanism of minimal periodontal regeneration by rhBMP-2. MATERIAL AND METHODS: hPDLSCs were isolated and cultured, and then transplanted into an ectopic subcutaneous mouse model using a carrier treated either with or without rhBMP-2. Comprehensive histologic, histometric and immunohistochemical analyses were performed after an 8-wk healing period. The effects of rhBMP-2 on the adipogenic and osteogenic/cementogenic differentiation of hPDLSCs were also evaluated. The effect of rhBMP-2 on both soluble and insoluble collagen synthesis was analyzed, and the expression of mRNA and protein for collagen types I, II, III and V was assessed. RESULTS: In the present study, rhBMP-2 promoted both adipogenic and osteogenic/cementogenic differentiation of hPDLSCs in vitro, and the in vivo potential of hPDLSCs to form mineralized cementum and organized PDL tissue was down-regulated following treatment with rhBMP-2. Collagen synthesis, which plays a crucial role in the regeneration of cementum and the periodontal attachment, was significantly reduced, with associated modification of the relevant mRNA and protein expression profiles. CONCLUSION: In summary, the findings of the present study suggest that enhanced adipogenic differentiation and inhibition of collagen synthesis by hPDLSCs appear to be partly responsible for the minimal effect of rhBMP-2 on cementum and PDL tissue regeneration by hPDLSCs.

Proapoptotic effects of tau cleavage product generated by caspase-3.

Using an in vitro translation assay to screen a human brain cDNA library, we isolated the microtubule-associated protein Tau and determined it to be a caspase-3 substrate whose C-terminal cleavage occurred during neuronal apoptosis. DeltaTau, the 50-kDa cleavage product, was detected by Western blot in apoptotic cortical cells probed with anti-PHF-1 and anti-Tau-5 antibodies, but not anti-T-46 antibody which recognizes the C-terminus. Overexpression of DeltaTau in SK-N-BE2(C) cells significantly increased the incidence of cell death. Staurosporine-induced Tau cleavage was blocked by 20 microM z-Asp-Glu-Val-Asp-chloromethylketone, a caspase-3 inhibitor, and in vitro, Tau was selectively cleaved by caspase-3 or calpain, a calcium-activated protease, but not by caspases-1, -8, or -9. (D421E)-Tau, a mutant in which Asp421 was replaced with a Glu, was resistant to cleavage by caspase-3 and tended to suppress staurosporine-induced cell death more efficiently than did wild-type Tau in both transient and stable expression systems. Finally, the incidence of DeltaTau-induced cell death was augmented by expression of Abeta precursor protein (APP) or Swedish APP mutant. Taken together, these results suggest that the caspase-3 cleavage product of Tau may contribute to the progression of neuronal cell death in Alzheimer's disease.

Effects of alpha-toxin of Staphylococcus aureus on the ciliary activity and ultrastructure of human nasal ciliated epithelial cells.

OBJECTIVE: The in vitro effects of staphylococcal alpha-toxin on ciliary activity were investigated at different concentrations and exposure times. STUDY DESIGN: Ciliated epithelial cells of the sphenoid sinus were taken from patients operated on for pituitary tumors. Video-computerized analysis technique and transmission electron microscopy were used to analyze the effects of the toxin on ciliary activity. METHODS: Ciliary beat frequency (CBF) was measured in four different concentrations of alpha-toxin including 0.1, 1, 10, and 50 microg/mL. CBF was measured at 2, 4, 6, 12, 24, and 48 hours after administration of the toxin. To observe reversibility of the reduced ciliary activity, after 24-hour incubation in the media containing 10 microg/mL of alpha-toxin, the media were replaced with alpha-toxin-free media. The tissues were also processed for transmission electron microscopy to observe ultrastructural changes of the epithelial cells. RESULTS: CBF increased significantly at 2-hour incubation and then decreased significantly after 12-hour incubation in 10 microg/mL of alpha-toxin (P< .05, repeated-measures ANOVA). The transmission electron microscopic findings showed mitochondrial swelling and a slight protrusion of the plasma membrane of the cilia. In toxin-free media, loss of ciliary activity was not recovered. CONCLUSIONS: CBF increased at first, but with increasing incubation time ciliary movements decreased gradually and stopped eventually. This loss of CBF may be an irreversible change associated with ultrastructural changes in the mitochondria and the plasma membrane of the cilia.

Effects of free radicals on ciliary movement in the human nasal epithelial cells.

OBJECTIVE: There have been few reports on the effects of free oxygen radicals on ciliary mobility of nasal respiratory epithelial cells. The aim of this study was to determine the effects of free radicals and antioxidants on human nasal epithelial cells (HNECs) using video-computerized analysis. METHODS: Human nasal epithelial cells were obtained from the nasal cavity of normal volunteers. Ciliary beat frequency (CBF) was calculated as the mean value of ten randomly selected cells. The proportion of the area with normal CBF (above 8 Hz) was calculated from 10 randomly selected sites per specimen. Free radicals were produced by xanthine-xanthine oxidase enzymatic system. The generation of free radicals was confirmed by chemoilluminometer. CBF and the proportion of the area with normal CBF were measured at every 5 min for 30 min after the addition of enzyme. For the evaluation of the antioxidant effects on free radical-mediated ciliary slowing in HNECs, cells were incubated in superoxide dismutase solution (300 unit/ml) for 30 min and 3-aminobenzamide (5 mM). RESULTS: Superoxide produced by 0.4 mM xanthine and 400 miliunit/ml xanthine oxidase decreased CBF (7.71 +/- 1.91 Hz). A total of 2 min later, ciliary slowing was evident (3.87 +/- 1.10 Hz). Regarding the changes in proportion of epithelial area that showed normal CBF experimental group showed a significant decrease in percentage of epithelial area with normal CBF over time. Superoxide dismutase prevented ciliary slowing (8.76 +/- 0.99 Hz). Moreover, 3-aminobenzamide, an inhibitor of the DNA repair enzyme poly-ADP ribose polymerase, prevented inhibition of CBF (8.32 +/- 0.61 Hz). CONCLUSIONS: These results suggest that oxygen-mediated damage to DNA may be the mechanism of the deterioration effects of oxygen radicals on the ciliated respiratory nasal epithelium.