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We compared rates of motor blockade, analgesia, adverse effects and patient satisfaction of 0.1% ropivacaine+fentanyl versus 0.2% ropivacaine-alone in a randomized, controlled trial. Fifty-four women who had undergone abdominal hysterectomy were randomly allocated into two groups to receive an epidural block at L1–2 or L2–3: group R received 0.2% ropivacaine-alone and group RF received 0.1% ropivacaine plus 2 μg fentanyl/ml, both at 8 ml/h. Rescue analgesia was provided via a morphine-loaded PCA device. Motor blockade (using a modified Bromage scale), pain intensity (visual analogue scale (VAS)), morphine consumption, level of sensory blockade and adverse effects, were measured at 4, 8 and 21 h after infusion. Patient satisfaction with pain management was assessed at the end of the study. The rates of motor blockade were not different at 8 h after infusion but at 21 h, group RF had significantly less motor blockade than group R. There were no differences in VAS, level of sensory blockade, adverse effects and patient satisfaction. Morphine consumption at each measurement was comparable but the total amount used by group RF was less than group R (12 mg versus 20 mg, P=0.049). Therefore, 0.1% ropivacaine with fentanyl 2 μg/ml appears to offer advantages over 0.2% ropivacaine-alone.  相似文献   
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Detection of beta-defensins secreted by human oral epithelial cells   总被引:12,自引:0,他引:12  
Human beta-defensins are antimicrobial peptides that may be critical in the innate immune response to infection. hBD1 and hBD2 are expressed in oral epithelial cells and are detected near the surface of oral tissue, consistent with a role in the epithelial protective barrier function. In this report, we examine secretion of beta-defensins in vitro and in biological fluid using ProteinChip(R) Array, surface enhanced laser desorption/ionization (SELDI) technology combined with time-of-flight mass spectrometry. We show that the 47-amino acid form of hBD1 and the 41-amino acid form of hBD2 are the major secreted forms. These forms are both expressed and secreted under conditions anticipated from previous analysis of beta-defensin mRNAs; specifically, hBD1 is detected in culture supernatant from both unstimulated and stimulated cells, and hBD2 is detected only in stimulated cells. Identity of hBD1 and hBD2 was confirmed by immunocapture on the ProteinChip surface. Both peptides are also present in gingival crevicular fluid that accumulates between the tissue and tooth surface, although hBD1 is also found in several smaller forms suggesting extracellular proteolysis. This methodology offers several technical advantages for detection of defensins in biological fluids, including ease and speed of screening, no need for HPLC preliminary processing, and small sample size.  相似文献   
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The sorption-enhanced steam reforming of ethanol (SESRE) has recently been reported as a novel process for hydrogen (H2) production. SESRE can operate well on a Ni-based catalyst with dolomite as a sorbent in packed-bed reactors. In this study, the circulating fluidized bed (CFB) concept was proposed to obtain higher productivity and continuous operation of SESRE. Particular focus was directed to the design and selection of suitable operating conditions of the CFB riser. Two-dimensional transient models using the Euler–Euler approach and the kinetic theory of granular flows were applied to investigate the H2 production performance from a pilot-scale riser. The 2k full factorial design method was utilized to examine the significances of five specific parameters, namely, the riser diameter, inlet temperature, catalyst-to-sorbent ratio, solid flux, and inlet gas velocity on two response variables, namely, H2 purity and H2 flux. From the ANOVA results, either the main effect or the interactions of each parameter were shown to be significant on both the H2 purity and the H2 flux, particularly the riser diameter and the solid flux. For optimizing the operation and reaction parameters, the best case was the system with riser diameter of 0.2 m, inlet temperature of 600 °C, catalyst-to-sorbent ratio of 2.54 kg kg−1, solid flux of 200 kg m−2 s−1, and gas velocity of 3 m s−1, obtaining H2 purity of 91.30% on a dry basis with a significantly high H2 flux of 0.147 kg m−2 s−1. The hydrodynamics showed that SESRE reached breakthrough within the bottom dense zone. However, incomplete conversion occurred in the core of the riser because of the very dilute bed.

The sorption-enhanced steam reforming of ethanol (SESRE) has recently been reported as a novel process for hydrogen (H2) production.  相似文献   
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ObjectiveTo examine CD99 expression and its functional role in ICAM-1 induction in human gingival fibroblasts (HGFs) and human gingival epithelial cells (HGECs) by activating cells with anti-CD99 monoclonal antibody, MT99/3.BackgroundEngagement of CD99 with agonistic antibodies has been shown to regulate immune responses, cell adhesion and migration, and cell death in several studies. Particularly, this engagement results in transendothelial migration of leukocytes mediated by intercellular adhesion molecule-1 (ICAM-1) induction in endothelial cells.MethodsTotal mRNA and protein were isolated from HGFs and HGECs for analyses of CD99 and ICAM-1 expression. Surface expression of CD99 and ICAM-1 was analysed by flow cytometry, and the detection of soluble ICAM-1 was assayed by immunoprecipitation and ELISA.ResultsCD99 surface expression was constitutive on HGFs to a greater extent than that on HGECs. CD99 ligation with MT99/3 induced ICAM-1 mRNA expression in HGFs, but not in HGECs. Interestingly, CD99 ligation led to an increased level of soluble ICAM-1 detected in culture supernatant, whereas interleukin-1β (IL-1β) treatment induced expression of membrane-bound ICAM-1. Furthermore, ICAM-1 induction by CD99 engagement was demonstrated to involve the activation of the p50 subunit of nuclear factor-kappaB (NF-κB), extracellular signal-regulated kinase, and p46 c-Jun N-terminal kinase that differed from that by IL-1β treatment.ConclusionOur study has shown the involvement of CD99 ligation in the up-regulation of ICAM-1 expression and its secretion in gingival fibroblasts, which may be essential for better understanding of the pathogenesis of periodontal disease.  相似文献   
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Background: A disintegrin and metalloproteinase 8 (ADAM8) is involved in inflammation and is essential for osteoclastogenesis. Elevated ADAM8 levels are detected in human serum and other body fluids in several inflammatory conditions. Therefore, we hypothesized that ADAM8 levels are also raised in gingival crevicular fluid (GCF) of patients with periodontal diseases. Methods: Forty‐five patients with periodontal diseases (n = 15 for each group: the group of patients with gingivitis, the group with aggressive periodontitis [AgP], and the group with chronic periodontitis [CP]) and 15 volunteers who exhibited healthy gingiva were recruited. Four periodontal parameters, gingival index, plaque index, probing depth, and clinical attachment level, were recorded before GCF collection. The presence of ADAM8 in GCF was shown by immunoblotting using anti‐human ADAM8 polyclonal antibody against its prodomain, and the ADAM8 levels were measured by an enzyme‐linked immunosorbent assay. Results: Four immunoreactive bands at 120, 70, 50, and <30 kDa were detected in the groups of patients with periodontitis, whose intensities were stronger than those in the group of patients with gingivitis, consistent with significantly greater ADAM8 levels in both groups of patients, with either CP or AgP, than those in the group of patients with gingivitis and in the group that was healthy (P <0.001). Moreover, the ADAM8 levels correlated significantly with the four periodontal parameters (P <0.001), indicating that ADAM8 levels are positively associated with the degree of periodontal tissue inflammation and destruction. Conclusions: The ADAM8 levels are elevated in the GCF of patients with periodontal diseases, including gingivitis, CP, and AgP, in comparison to control participants who are healthy, and they correlate with four clinical parameters that reflect the degree of disease severity.  相似文献   
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Human beta-defensin expression correlates with differentiation in oral epithelium, and calcium ion, an important regulator of epithelial differentiation, plays a critical role in regulation of human beta-defensin-2 (hBD-2) mRNA expression. Phospholipase D (PLD) also regulates epithelial differentiation. Therefore, we examined the role of PLD in hBD-2 up-regulation by cell wall extract of Fusobacterium nucleatum and phorbol 12-myristate 13-acetate (PMA), two known hBD-2 activators. We found that hBD-2 mRNA up-regulation in human gingival epithelial cells (HGECs) by these two activators was mediated by PLD activation and blocked by ethanol and 1-butanol, PLD inhibitors. PLD activity was induced by stimulation with these two activators, and phosphatidic acid (PA), a product generated from the PLD enzymatic activity, was detected in stimulated HGECs. Dioctanoyl PA commonly used for PA induced hBD-2 mRNA expression. mRNAs for PLD1 alpha and beta splice variants as well as PLD1 protein were constitutively expressed, whereas mRNA and protein for PLD2 were expressed at much lower levels than those for PLD1. Moreover, pre-treatment with (+/-)-propanolol, an inhibitor of phosphatidic acid phosphohydrolases that are the downstream signaling molecules in the PLD pathway, significantly blocked hBD-2 mRNA induction by PMA in a dose-dependent manner. In conclusion, these findings indicate the involvement of PLD activation in hBD-2 up-regulation in HGECs, which correlates with the state of epithelial differentiation.  相似文献   
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