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41.
42.
Pharmacokinetics of mitomycin C in patients receiving the drug alone or in combination 总被引:2,自引:0,他引:2
G A van Hazel M Scott J Rubin C G Moertel R T Eagan M J O'Connell J S Kovach 《Cancer treatment reports》1983,67(9):805-810
We have characterized plasma pharmacokinetics in 30 patients receiving mitomycin C (mitomycin) in doses ranging from 6 to 20 mg/m2 by iv bolus injection, either alone or in combination with other chemotherapeutic drugs. Plasma elimination of the drug was described by a two-compartment model in all but three cases, giving mean values for alpha-half-life of 8.2 mins, beta-half-life of 51.8 mins, and total body clearance of 332.9 ml/min/m2. The mean urinary excretion was 8.1% of the total dose administered. We did not detect alterations in pharmacologic parameters related to liver dysfunction, dose of mitomycin, and concomitant administration of other cytotoxic drugs. 相似文献
43.
A prospective, comparative study of empiric amphotericin B with, or without, granulocyte colony stimulating factor was carried out to assess whether the addition of granulocyte colony stimulating factor to empiric amphotericin B improves the clinical response in neutropenic patients with suspected or proven fungal infection. Fifty nine neutropenic adults with haematological malignancy and antibiotic-refractory fever or clinical evidence of deep-seated fungal infection were studied. Patients received intravenous colloidal amphotericin B (1 milligram per kilogram body weight) with or without subcutaneous granulocyte colony stimulating factor (three to five micrograms per kilogram body weight). Thirty patients received amphotericin alone and 29 amphotericin plus granulocyte colony stimulating factor. Nearly twice as many patients responded to amphotericin B with concomitant administration of granulocyte colony stimulating factor (62%) as responded to amphotericin alone (33%; difference in proportions 0.29, 95%CI 0.03-0.54). Clinical response in patients receiving granulocyte colony stimulating factor coincided with neutrophil recovery in most cases. Addition of granulocyte colony stimulating factor to empiric amphotericin B significantly reduced the number of patients requiring salvage therapy with lipid-associated or liposomal formulations of amphotericin B addition of granulocyte colony stimulating factor to empiric intravenous amphotericin B improves the response rate and thereby reduces the number of patients requiring salvage therapy with liposomal or lipid-associated preparations of amphotericin B. 相似文献
44.
Soluble ICAM-1, MCP-1, and MIP-2 protein secretion by rat pleural mesothelial cells following exposure to amosite asbestos 总被引:3,自引:0,他引:3
Pleural inflammation is a sequela of exposure to toxic mineral fibers such as amosite asbestos. This inflammatory response involves the influx of leukocytes from the vasculature into the pleural space. Adhesion molecules such as intercellular adhesion molecule-1 (ICAM)-1 and chemokines such as monocyte chemoattractant protein-1 (MCP)-1 and macrophage inhibitory protein-2 (MIP)-2 are known to be important in pulmonary inflammation following inhalation of particulate matter. However, little is known about their role in pleural inflammation secondary to amosite asbestos exposure. Because the pleural mesothelial cell is believed to be a key target cell of asbestos exposure, the purpose of this study was to determine if ICAM-1, MCP-1, and MIP-2 proteins were secreted by these mesothelial cells following in vitro and in vivo exposure to amosite asbestos. Increased levels of ICAM-1 and MCP-1 protein were measured following 24 or 48 hours exposure of cultured rat pleural mesothelial cells to amosite fibers (1.5 to 5.0 micro g/cm(2)). Increased levels of ICAM-1, MCP-1, and MIP-2 protein were found in pleural lavage fluid from Fischer-344 rats exposed to amosite asbestos for 4 and 12 weeks and after a 12-week recovery period (following the 12-week exposure period). These findings suggest that the secretion of ICAM-1, MCP-1, and MIP-2 by rat pleural mesothelial cells may contribute to amosite-induced pleural inflammation. 相似文献
45.
46.
Michael Lean Naomi Brosnahan Philip McLoone Louise McCombie Anna Bell Higgs Hazel Ross Mhairi Mackenzie Eleanor Grieve Nick Finer John Reckless David Haslam Billy Sloan David Morrison 《The British journal of general practice》2013,63(607):e115-e124
Background
There is no established primary care solution for the rapidly increasing numbers of severely obese people with body mass index (BMI) > 40 kg/m2.Aim
This programme aimed to generate weight losses of ≥15 kg at 12 months, within routine primary care.Design and setting
Feasibility study in primary care.Method
Patients with a BMI ≥40 kg/m2 commenced a micronutrient-replete 810–833 kcal/day low-energy liquid diet (LELD), delivered in primary care, for a planned 12 weeks or 20 kg weight loss (whichever was the sooner), with structured food reintroduction and then weight-loss maintenance, with optional orlistat to 12 months.Result
Of 91 patients (74 females) entering the programme (baseline: weight 131 kg, BMI 48 kg/m2, age 46 years), 58/91(64%) completed the LELD stage, with a mean duration of 14.4 weeks (standard deviation [SD] = 6.0 weeks), and a mean weight loss of 16.9 kg (SD = 6.0 kg). Four patients commenced weight-loss maintenance omitting the food-reintroduction stage. Of the remaining 54, 37(68%) started and completed food reintroduction over a mean duration of 9.3 weeks (SD = 5.7 weeks), with a further mean weight loss of 2.1 kg (SD = 3.7 kg), before starting a long-term low-fat-diet weight-loss maintenance plan. A total of 44/91 (48%) received orlistat at some stage. At 12 months, weight was recorded for 68/91 (75%) patients, with a mean loss of 12.4 kg (SD = 11.4 kg). Of these, 30 (33% of all 91 patients starting the programme) had a documented maintained weight loss of ≥15 kg at 12 months, six (7%) had a 10–15 kg loss, and 11 (12%) had a 5–10 kg loss. The indicative cost of providing this entire programme for wider implementation would be £861 per patient entered, or £2611 per documented 15 kg loss achieved.Conclusion
A care package within routine primary care for severe obesity, including LELD, food reintroduction, and weight-loss maintenance, was well accepted and achieved a 12-month-maintained weight loss of ≥15 kg for one-third of all patients entering the programme. 相似文献47.
James Jamison Felix Naughton Hazel Gilbert Stephen Sutton 《Journal of Applied Biobehavioral Research》2013,18(1):1-23
Recent advances in technology have given rise to novel methods of delivering support to smokers wanting to quit. Mobile phone text messaging permits the delivery of quitting advice at any time, with little effort and at minimal cost. We examined smokers' attitudes toward text messaging as a tool to facilitate smoking cessation as well as preferences for message content and text delivery. Six focus groups were conducted from a total of 24 participants, with additional information obtained via paper questionnaire. Interaction with the text messaging system, tailoring message content and delivery, highlighting the positive effects of quitting, and offering encouragement by text were considered important features of a text support program. Future text messaging interventions may benefit from these findings. 相似文献
48.
Man Lyang Kim Jae Jin Chae Yong Hwan Park Dominic De Nardo Roslynn A. Stirzaker Hyun-Ja Ko Hazel Tye Louise Cengia Ladina DiRago Donald Metcalf Andrew W. Roberts Daniel L. Kastner Andrew M. Lew Dena Lyras Benjamin T. Kile Ben A. Croker Seth L. Masters 《The Journal of experimental medicine》2015,212(6):927-938
Gain-of-function mutations that activate the innate immune system can cause systemic autoinflammatory diseases associated with increased IL-1β production. This cytokine is activated identically to IL-18 by an intracellular protein complex known as the inflammasome; however, IL-18 has not yet been specifically implicated in the pathogenesis of hereditary autoinflammatory disorders. We have now identified an autoinflammatory disease in mice driven by IL-18, but not IL-1β, resulting from an inactivating mutation of the actin-depolymerizing cofactor Wdr1. This perturbation of actin polymerization leads to systemic autoinflammation that is reduced when IL-18 is deleted but not when IL-1 signaling is removed. Remarkably, inflammasome activation in mature macrophages is unaltered, but IL-18 production from monocytes is greatly exaggerated, and depletion of monocytes in vivo prevents the disease. Small-molecule inhibition of actin polymerization can remove potential danger signals from the system and prevents monocyte IL-18 production. Finally, we show that the inflammasome sensor of actin dynamics in this system requires caspase-1, apoptosis-associated speck-like protein containing a caspase recruitment domain, and the innate immune receptor pyrin. Previously, perturbation of actin polymerization by pathogens was shown to activate the pyrin inflammasome, so our data now extend this guard hypothesis to host-regulated actin-dependent processes and autoinflammatory disease.Autoinflammatory syndromes are caused by dysregulation of the innate immune system, frequently affecting the inflammasome or other pathogen recognition pathways and leading to the overproduction of active IL-1β and IL-18 (Masters et al., 2009). To date, there are at least 12 known genetic causes of autoinflammatory disease, including familial Mediterranean fever (FMF), hyper-IgD syndrome, and cryopyrin-associated periodic syndrome. Therapeutic options for these diseases include nonsteroidal antiinflammatory drugs, corticosteroids, colchicine (for FMF), anti-TNF, and direct blockade of IL-1, which can be highly efficacious (Masters et al., 2009; Caso et al., 2013). IL-18 and IL-1β are produced in many cells, including monocytes and macrophages (Okamura et al., 1995; Ushio et al., 1996). IL-18 and IL-1β are produced as precursors and do not have a signal peptide to facilitate their secretion; instead, they are activated and released extracellularly as mature proteins after cleavage by caspase-1 (Li et al., 1995; Ghayur et al., 1997; Gu et al., 1997). Despite these similarities, there is no known hereditary autoinflammatory disease where the pathology is caused exclusively by IL-18.The inflammasome is an intracellular molecular platform that forms in response to pathogen- or danger-associated molecular patterns (DAMPs), leading to recruitment and activation of caspase-1 (Martinon et al., 2002; Schroder and Tschopp, 2010). A growing number of inflammasomes have been reported, each nucleated by a different innate immune receptor, such as NLRP1 (Martinon et al., 2000; Boyden and Dietrich, 2006), NLRP3 (Agostini et al., 2004), NLRC4 (Franchi et al., 2006), pyrin (Chae et al., 2011), and AIM2 (Hornung et al., 2009). Apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) is a key adaptor used by most of these innate immune receptors to interact with and recruit caspase-1 (Srinivasula et al., 2002). Activating mutations in NLRP3 result in increased IL-1β and IL-18 production, which can be prevented in mice by deleting caspase-1 or ASC. Furthermore, deleting either the IL-18R or the IL-1R can both independently protect mice from this NLRP3-mediated autoinflammatory disease (Brydges et al., 2013). For the FMF protein, pyrin, activating mutations induce ASC-dependent but NLRP3-independent IL-1β activation and cause severe autoinflammation in mice (Chae et al., 2011). Interestingly, pyrin interacts with ASC, microtubules, and actin filaments (Mansfield et al., 2001; Richards et al., 2001; Waite et al., 2009), and it has recently been shown that modification of RhoGTPases by bacterial toxins can trigger the pyrin inflammasome, perhaps via modulation of actin dynamics (Xu et al., 2014). This raises the fascinating prospect of a link between perturbations in the actin cytoskeleton and autoinflammatory disease.Wdr1 is required for disassembly of actin filaments in conjunction with the actin-depolymerizing factor/cofilin family of proteins. Mice homozygous for a hypomorphic allele of Wdr1 (Wdr1rd/rd) exhibit spontaneous autoinflammatory disease and thrombocytopenia (Kile et al., 2007). Both defects have been suggested to result from a disruption in actin dynamics. Thrombocytopenia results from defects in megakaryocytes, a cell type that is entirely dependent on a functional cytoskeleton to shed platelets (Patel et al., 2005). Wdr1 mutant mice also exhibit neutrophilia; however, the critical inflammatory mediators and cell types important for the development of inflammation in this genetic condition are unclear (Kile et al., 2007). Intriguingly, Wdr1 was found to be secreted after caspase-1 activation (Keller et al., 2008).We examined the role of key inflammatory mediators that drive autoinflammation in Wdr1rd/rd mice and demonstrated that this disease is IL-18 dependent, but IL-1 independent. As expected, this IL-18 is produced by the inflammasome; however, it is not produced from neutrophils or macrophages, but instead only from monocytes. Finally, we found that the autoinflammatory disease was mediated by pyrin, providing evidence that this innate immune receptor recognizes alterations in the actin polymerization pathway. 相似文献
49.
Helen A. Fletcher Rachel Tanner Robert S. Wallis Joel Meyer Zita-Rose Manjaly Stephanie Harris Iman Satti Richard F. Silver Dan Hoft Beate Kampmann K. Barry Walker Hazel M. Dockrell Uli Fruth Lew Barker Michael J. Brennan Helen McShane 《Clinical and Vaccine Immunology : CVI》2013,20(11):1683-1689
Despite the widespread use of the Mycobacterium bovis BCG vaccine, there are more than 9 million new cases of tuberculosis (TB) every year, and there is an urgent need for better TB vaccines. TB vaccine candidates are selected for evaluation based in part on the detection of an antigen-specific gamma interferon (IFN-γ) response. The measurement of mycobacterial growth in blood specimens obtained from subjects immunized with investigational TB vaccines may be a better in vitro correlate of in vivo vaccine efficacy. We performed a clinical study with 30 United Kingdom adults who were followed for 6 months to evaluate the abilities of both a whole-blood- and a novel peripheral blood mononuclear cell (PBMC)-based mycobacterial growth inhibition assay to measure a response to primary vaccination and revaccination with BCG. Using cryopreserved PBMCs, we observed a significant improvement in mycobacterial growth inhibition following primary vaccination but no improvement in growth inhibition following revaccination with BCG (P < 0.05). Mycobacterial growth inhibition following primary BCG vaccination was not correlated with purified protein derivative (PPD) antigen-specific IFN-γ enzyme-linked immunospot (ELISPOT) responses. We demonstrate that a mycobacterial growth inhibition assay can detect improved capacity to control growth following primary immunization, but not revaccination, with BCG. This is the first study to demonstrate that an in vitro growth inhibition assay can identify a difference in vaccine responses by comparing both primary and secondary BCG vaccinations, suggesting that in vitro growth inhibition assays may serve as better surrogates of clinical efficacy than the assays currently used for the assessment of candidate TB vaccines. 相似文献
50.
Soujanya Bogarapu Michael D. Puchalski Melanie D. Everitt Richard V. Williams Hsin-Yi Weng Shaji C. Menon 《Pediatric cardiology》2016,37(4):663-673
Myocardial fibrosis is a risk factor for sudden cardiac death in hypertrophic cardiomyopathy (HCM) and is conventionally identified by cardiac magnetic resonance imaging (CMR) using late gadolinium enhancement (LGE). This study evaluates utility of a novel 16-segment CMR feature tracking (CMR-FT) technique for measuring left ventricular (LV) strain (S) and strain rate (SR) on non-contrast cine images to detect myocardial fibrosis in pediatric HCM. We hypothesized that CMR-FT-derived S and SR will accurately differentiate HCM patients with and without myocardial fibrosis. Consecutive children with HCM who underwent CMR with LGE at our institution from 2006 to 2014 were included. Global and regional longitudinal, radial and circumferential S and SR of the LV in 2D and 3D were obtained using a CMR-FT software. Comparisons were made between HCM patients with (+LGE) and without (?LGE) delayed enhancement. Of the 29 HCM patients (mean age 13.5 ± 6.1 years; 52 % males), 11 (40 %) patients (mean age 17.5 ± 8.4 years) had +LGE. Global longitudinal, circumferential and radial S and SR were lower in +LGE compared to ?LGE patients, in both 2D and 3D. Regional analysis revealed lower segmental S and SR in the septum with fibrosis compared to free wall without fibrosis. A global longitudinal S of ≤ ?12.8 had 91 % sensitivity and 89 % specificity for detection of LGE. In pediatric HCM patients with myocardial fibrosis, global LV longitudinal, circumferential and radial S and SR were reduced, specifically in areas of fibrosis. A global longitudinal S of ≤ ?12.8 detected patients with fibrosis with high degree of accuracy. This novel CMR-FT technique may be useful to identify myocardial fibrosis and risk-stratify pediatric HCM without use of contrast agents. 相似文献