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The effects of cyclic AMP-related compounds and beta adrenoceptor agonists on the basal and lipopolysaccharide (LPS)-stimulated release of endothelin-1 (ET-1) from guinea-pig tracheal epithelial cells (GPTEpCs) in culture were studied. Forskolin (a potent activator of adenylyl cyclase), 8-bromo-cyclic AMP (a cyclic AMP analogue), salbutamol and salmeterol (two beta 2-adrenoceptor agonists), were used to increase cyclic AMP levels. Cultured GPTEpCs released ET-1 continuously over a 24 h incubation period. The values reached 1,938 ± 122 pg/mg of total cell proteins after 24 h. LPS (10 μg/ml) significantly stimulated the release of ET-1 by 1.6- to 1.8-fold, up to 1,262 ± 56 pg/mg total cell proteins after an 8 h incubation period. Compound 8-bromo-cyclic AMP (10−5, 10−4 and 10−3 M) reduced the basal release of ET-1 from GPTEpCs by up to 31% (P < 0.01) and the LPS stimulated release by up to 42% (P < 0.05), after an 8 h incubation period. Forskolin (10−6, 10−5 and 10−4 M) also inhibited the basal release of ET-1 by up to 28% (P < 0.05) and LPS-stimulated release of ET-1 by up to 50% (P < 0.05), after an 8 h incubation period. At the concentration of 10−5 M, forskolin increased cyclic AMP levels in GPTEpCs by 17-fold (P < 0.001) in the medium, 15 min after the beginning of the incubation. Salbutamol (10−8 to 10−6 M) had no effect on the basal production and release of ET-1 after 8 h. Conversely, this short acting beta 2-adrenoceptor agonist significantly reduced LPS-mediated increase of ET-1 production by up to 55% (P < 0.05) after an 8 h incubation period. Salmeterol (10−9 M to 10−5 M) inhibited basal and LPS-stimulated production and release of ET-1 after an 8 h incubation period (between 44 and 51%, P < 0.01). Both salbutamol and salmeterol (10−6 M) increase cyclic AMP levels by five- and twofold, respectively (P < 0.05). In summary, these observations indicate that beta 2-adrenoceptor agonists or cyclic AMP enhancers can modulate both basal and more markedly, the enhanced production of ET-1 from LPS-activated guinea pig airway EpCs. In addition, these compounds increase cyclic AMP levels in the cells. It is suggested that there is a correlation between cyclic AMP increase and inhibition of ET-1 release by guinea pig airway EpCs. Since ET-1 production was shown to be elevated in asthmatic subjects and in patients suffering from other inflammatory lung disorders, the inhibition of its production by beta adrenoceptor agonists, such as salbutamol and salmeterol, could be added to their therapeutical benefits.  相似文献   
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Fifteen per cent of metastatic breast cancer will develop symptomatic leptomeningeal metastases. The introduction of trastuzumab (Herceptin) therapy has improved the response rates of survival of patients with metastatic breast cancer overexpressing HER2. Although previous studies are retrospective and of limited number, involving small study groups and different types of patient management, several authors have reported a 30% incidence of leptomeningeal metastases in patients with metastatic breast cancer overexpressing HER2 who were treated with trastuzumab, while 70 to 80% of cases of the disease were controlled systemically. In order to improve control of the disease at the level of the central nervous system (CNS), routine detection of leptomeningeal metastases in high-risk patients could be offered. CA 15-3 in cerebrospinal fluid (CSF) detection might be useful in helping to diagnose CNS metastases, particularly where cytology results are negative--which applies to 30% of cases--because tumor markers are more sensitive in detecting the tumor process. Our study validate CA 15-3 measurement in CSF and reference values were given.  相似文献   
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Health promotion programs represent a salient means through which physical activity promoters can cultivate positive health behavior change and maintenance. The messages communicated within these programs serve as an essential component as they are often used to convey valuable information, resources, or tools that facilitate health behavior initiation and sustained engagement. Identifying the most effective way to communicate health promotion information is, therefore, of considerable importance to ensuring that people not only attend to these messages, but also connect with and internalize the information conveyed within them. This paper was written to (1) summarize and evaluate the most prominent reviewed research approaches of message framing and tailoring to message design; and (2) offer a comprehensive messaging strategy to promote sustained health behavior change. A review of the literature demonstrated that a messaging strategy that has consistently led to healthy behavior change has yet to be identified. Furthermore, scholars have articulated that a multi-theoretical approach that places emphasis on facilitating motivation and healthy behavior change needs to be employed. Thus, this paper proposes and provides recommendations for employing the Comprehensive Messaging Strategy for Sustained Behavior Change (CMSSBC), which advocates tailoring messages to peoples’ stage of change and framing them to focus on self-determined motives and intrinsic goals.  相似文献   
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Active antibody‐mediated rejection (AMR) is a potentially devastating complication and consistently effective treatment remains elusive. We hypothesized that the reversal of acute AMR requires rapid elimination of antibody‐secreting plasma cells (PC) with a proteasome inhibitor, bortezomib, followed by the sustained inhibition of PC generation with CTLA4‐Ig or belatacept (B/B). We show in mice that B/B therapy selectively depleted mature PC producing donor‐specific antibodies (DSA) and reduced DSA, when administered after primary and secondary DSA responses had been established. A pilot investigation was initiated to treat six consecutive patients with active AMR with B/B. Compassionate use of this regimen was initiated for the first patient who developed early, severe acute AMR that did not respond to steroids, plasmapheresis, and intravenous immunoglobulin after his third kidney transplant. B/B treatment resulted in a rapid reversal of AMR, leading us to treat five additional patients who also resolved their acute AMR episode and had sustained disappearance of circulating DSA for ≤30 months. This study provides a proof‐of‐principle demonstration that mouse models can identify mechanistically rational therapies for the clinic. Follow‐up investigations with a more stringent clinical design are warranted to test whether B/B improves on the standard of care for the treatment of acute AMR.  相似文献   
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Background contextThe ideal tissue-engineered solution for any bone graft substitute is to assist in the rapid formation of bone and facilitate fusion.PurposeThe present study aims to evaluate this E-BMP-2 (Escherichia coli–derived human bone morphogenetic protein-2) in ovine posterolateral lumbar fusion (PLF) to examine the influence of dose and overall performance in a model with similar graft size and diffusive challenges to the human.Study design/settingIn vivo large animal model study.MethodsAn adult ovine PLF was performed in 30 animals with groups of E-BMP-2 with a beta-tricalcium phosphate (β-TCP) carrier at three different dosages, β-TCP alone, and autograft from the iliac crest. The fusions were assessed by radiography (X-ray and microcomputed tomography), mechanical testing, and hard-tissue histology with bone labels at 6, 8, and 10 weeks along with routine paraffin histology at 12 weeks.ResultsResults showed increasing new bone and fusion rate with E-BMP-2 dose, whereas β-TCP alone was largely resorbed and did not achieve fusion in this model at 12 weeks. Autograft showed similar grading for the amount of bone between the transverse processes but a lower fusion rate than β-TCP/E-BMP-2 groups. Bone labels revealed new bone formation at all time points for the E-BMP2 groups, whereas the autograft group showed active bone formation at 10 weeks. Beta-tricalcium phosphate displayed reliable incorporation into the decorticated host bone, whereas limited new bone was found between the transverse processes. At the center of the fusion mass, increased E-BMP-2 dose led to increased incorporation of β-TCP by new bone.ConclusionsThese results suggest that E-BMP-2 was capable of producing posterolateral fusion in the ovine model that is equal to or superior to autologous graft in terms of fusion rate and mechanical strength. E-BMP-2 dose had considerable influence on β-TCP granule resorption.  相似文献   
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