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Histamine and Histamine H4 Receptor Promotes Osteoclastogenesis in Rheumatoid Arthritis.
Histamine H4 receptor (H4R) has immune-modulatory and chemotaxic effects in various immune cells. This study aimed to determine the osteoclastogenic role of H4R in rheumatoid arthritis (RA). The concentration of histamine in synovial fluid (SF) and sera in patients with RA was measured using ELISA. After RA SF and peripheral blood (PB) CD14+ monocytes were treated with histamine, IL-17, IL-21 and IL-22, and a H4R antagonist (JNJ7777120), the gene expression H4R and RANKL was determined by real-time PCR. Osteoclastogenesis was assessed by counting TRAP-positive multinucleated cells in PB CD14+ monocytes cultured with histamine, Th17 cytokines and JNJ7777120. SF and serum concentration of histamine was higher in RA, compared with osteoarthritis and healthy controls. The expression of H4R was increased in PB monocytes in RA patients. Histamine, IL-6, IL-17, IL-21 and IL-22 induced the expression of H4R in monocytes. Histamine, IL-17, and IL-22 stimulated RANKL expression in RA monocytes and JNJ7777120 reduced the RANKL expression. Histamine and Th17 cytokines induced the osteoclast differentiation from monocytes and JNJ7777120 decreased the osteoclastogenesis. H4R mediates RANKL expression and osteoclast differentiation induced by histamine and Th17 cytokines. The blockage of H4R could be a new therapeutic modality for prevention of bone destruction in RA
Transmission Schemes based on Sum Rate Analysis in Distributed Antenna Systems
In this paper, we study single cell multi-user downlink distributed antenna
systems (DAS) where antenna ports are geographically separated in a cell.
First, we derive an expression of the ergodic sum rate for the DAS in the
presence of pathloss. Then, we propose a transmission selection scheme based on
the derived expressions which does not require channel state information at the
transmitter. Utilizing the knowledge of distance information from a user to
each distributed antenna (DA) port, we consider the optimization of pairings of
DA ports and users to maximize the system performance. Based on the ergodic sum
rate expressions, the proposed scheme chooses the best mode maximizing the
ergodic sum rate among mode candidates. In our proposed scheme, the number of
mode candidates are greatly reduced compared to that of ideal mode selection.
In addition, we analyze the signal to noise ratio cross-over point for
different modes using the sum rate expressions. Through Monte Carlo
simulations, we show the accuracy of our derivations for the ergodic sum rate.
Moreover, simulation results with the pathloss modeling confirm that the
proposed scheme produces the average sum rate identical to the ideal mode
selection with significantly reduced candidates.Comment: 25 pages, 8 figures, submitted to IEEE Transactions on Wireless
Communications, May 201
Evaluation of Left Atrial Volumes Using Multidetector Computed Tomography: Comparison with Echocardiography
OBJECTIVE: To prospectively assess the relationship between the two different measurement methods for the evaluation of left atrial (LA) volume using cardiac multidetector computed tomography (MDCT) and to compare the results between cardiac MDCT and echocardiography. MATERIALS AND METHODS: Thirty-five patients (20 men, 15 women; mean age, 60 years) underwent cardiac MDCT angiography for coronary artery disease. The LA volumes were measured using two different methods: the two dimensional (2D) length-based (LB) method measured along the three-orthogonal planes of the LA and the 3D volumetric threshold-based (VTB) method measured according to the threshold 3D segmentation of the LA. The results obtained by cardiac MDCT were compared with those obtained by echocardiography. RESULTS: The LA end-systolic and end-diastolic volumes (LAESV and LAEDV) measured by the 2D-LB method correlated well with those measured by the 3D-VTB method using cardiac MDCT (r = 0.763, r = 0.786, p = 0.001). However, there was a significant difference in the LAESVs between the two measurement methods using cardiac MDCT (p < 0.05). The LAESV measured by cardiac MDCT correlated well with measurements by echocardiography (r = 0.864, p = 0.001), however with a significant difference (p < 0.01) in their volumes. The cardiac MDCT overestimated the LAESV by 22% compared to measurements by echocardiography. CONCLUSION: A significant correlation was found between the two different measurement methods for evaluating LA volumes by cardiac MDCT. Further, cardiac MDCT correlates well with echocardiography in evaluating the LA volume. However, there are significant differences in the LAESV between the two measurement methods using cardiac MDCT and between cardiac MDCT and echocardiographyope
Effects of Dexmedetomidine on Serum Interleukin-6, Hemodynamic Stability, and Postoperative Pain Relief in Elderly Patients under Spinal Anesthesia
The beneficial effects of dexmedetomidine (DEX) have not been extensively investigated in elderly patients receiving spinal anesthesia. This study evaluated the effects of intravenous DEX infusion on stress and hemodynamic response, as well as on postoperative analgesia in elderly patients undergoing total knee arthroplasty (TKA). We randomly allocated 45 adult patients to 3 patient groups (n=15 each): uni-saline group patients underwent unilateral TKA with saline administration, uni-DEX group patients underwent unilateral TKA with DEX administration, and bilateral-DEX group patients underwent bilateral TKA with DEX administration. Serum interleukin-6 (IL-6) levels were significantly lower in the bilateral-DEX group than in the uni-saline group 6 and 24h postoperatively, and were negatively correlated with total DEX dosage 24h postoperatively. Bradycardia occurred more frequently in the uni-DEX and bilateral-DEX groups than in the uni-saline group. The total dose of required supplementary analgesics was significantly higher in the uni-saline group than in the uni-DEX and bilateral-DEX groups 6h postoperatively. The results indicate that perioperative intravenous DEX administration decreases postoperative serum IL-6 levels in patients undergoing bilateral TKA, and has a postoperative analgesic effect in patients undergoing unilateral or bilateral TKA
Comparison of implant stability after different implant surface treatments in dog bone
OBJECTIVES: The purpose of this investigation was to evaluate the effects of different implant surface treatments on implant stability in dog mandibles. MATERIAL AND METHODS: A total of 30 implants (Dentium Co, Seoul, Korea) were placed in 5 dog mandibles. Bone quality was assessed at each site. Implant stability was evaluated using 2 different methods. An OsstellTM resonance frequency analyzer (RFA) was used to determine the stability at baseline (day 1), and 3, 6 and 10 weeks after surgery. Animals were euthanized 10 weeks after implant installation. Specimens were obtained and submitted to the laboratory processing. Sections were stained with hematoxylin and eosin for histologic and histomorphometric analyses. All implantation sites in dog mandibles demonstrated bone types II and III. RESULTS AND CONCLUSIONS: All implants showed good primary stability at baseline in terms of insertion torque. The results of this study suggest that surface treatment may have significant effects on biological stability 3 weeks after implant placement. Further studies are needed to confirm these initial observations in poor quality bone
Boundary integral equation method for resonances in gradient index cavities designed by conformal transformation optics
In the case of two-dimensional gradient index cavities designed by the
conformal transformation optics, we propose a boundary integral equation method
for the calculation of resonant mode functions by employing a fictitious space
which is reciprocally equivalent to the physical space. Using the Green's
function of the interior region of the uniform index cavity in the fictitious
space, resonant mode functions and their far-field distributions in the
physical space can be obtained. As a verification, resonant modes in
lima\c{c}on-shaped transformation cavities were calculated and mode patterns
and far-field intensity distributions were compared with those of the same
modes obtained from the finite element method.Comment: 13 pages, 6 figure
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