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71.
Newcombe PA Sheffield JK Juniper EF Marchant JM Halsted RA Masters IB Chang AB 《Chest》2008,133(2):386-395
BACKGROUND: Chronic cough affects at least 7% of children, and the impact of this on families is significant. Although adult cough-specific quality-of-life (QOL) instruments have been shown to be a useful cough outcome measure, no suitable cough-specific QOL for parents of children with chronic cough exists. This article compares two methods of item reduction (clinical impact and psychometric) and reports on the statistical properties of both QOL instruments. METHOD: One hundred seventy children (97 boys and 73 girls; median age, 4 years; interquartile range, 3 to 7.25 years) and one of their parents participated. A preliminary 50-item parent cough-specific QOL (PC-QOL) questionnaire was developed from conversations with parents of children with chronic cough (ie, cough for > 3 weeks). Parents also completed generic QOL questionnaires (eg, Pediatric Quality of Life Inventory, version 4.0 [PedsQL4.0] and the 12-item Short Form Health Survey, version 2 [SF-12v2]). RESULTS: The clinical impact and psychometric method of item reduction resulted in 27-item and 26-item PC-QOL questionnaires, respectively, with approximately 50% of items overlapping. Internal consistency among the final items from both methods was excellent. Some evidence for concurrent and criterion validity of both methods was established as significant correlations were found between subscales of the PC-QOL questionnaire and the scales of the SF-12v2 and PedsQL4.0 scores. The PC-QOL questionnaire derived from both methods was sensitive to change following an intervention. CONCLUSION: Chronic cough significantly impacts on the QOL of both parents and children. Although the PC-QOL questionnaires derived from a clinical impact method and from a psychometric method contained different items, both versions were shown to be internally consistent and valid. Further testing is required to compare both final versions to objective and subjective cough measures. 相似文献
72.
Benjamin F. Ricciardi Gowrishankar Muthukrishnan Elysia Masters Mark Ninomiya Charles C. Lee Edward M. Schwarz 《Current reviews in musculoskeletal medicine》2018,11(3):389-400
Purpose of Review
The incidence of complications from prosthetic joint infection (PJI) is increasing, and treatment failure remains high. We review the current literature with a focus on Staphylococcus aureus pathogenesis and biofilm, as well as treatment challenges, and novel therapeutic strategies.Recent Findings
S. aureus biofilm creates a favorable environment that increases antibiotic resistance, impairs host immunity, and increases tolerance to nutritional deprivation. Secreted proteins from bacterial cells within the biofilm and the quorum-sensing agr system contribute to immune evasion. Additional immunoevasive properties of S. aureus include the formation of staphylococcal abscess communities (SACs) and canalicular invasion. Novel approaches to target biofilm and increase resistance to implant colonization include novel antibiotic therapy, immunotherapy, and local implant treatments.Summary
Challenges remain given the diverse mechanisms developed by S. aureus to alter the host immune responses. Further understanding of these processes should provide novel therapeutic mechanisms to enhance eradication after PJI.73.
Human dihydrofolate reductase gene is located in chromosome 5 and is unlinked to the related pseudogenes. 总被引:4,自引:4,他引:4
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B J Maurer P E Barker J N Masters F H Ruddle G Attardi 《Proceedings of the National Academy of Sciences of the United States of America》1984,81(5):1484-1488
The chromosomal location of the human dihydrofolate reductase (DHFR; EC 1.5.1.3) gene that is amplified in a methotrexate-resistant human cell line has been investigated by screening a large number of human-mouse cell hybrids containing overlapping subsets of human chromosomes. A correlation of genomic blotting data with the chromosome constitution of the individual cell hybrids has allowed the assignment of the human DHFR gene to chromosome 5. This chromosome assignment has been confirmed by the observation of a concomitant loss of the human DHFR gene and of sensitivity to diphtheria toxin, a marker associated with chromosome 5, in two human-mouse cell hybrids selected for resistance to the toxin. Six EcoRI fragments of human DNA containing DHFR pseudogenes or other DHFR-related sequences have been assigned to chromosomes other than chromosome 5. 相似文献
74.
硒对鸡胚脑发育的影响 总被引:1,自引:5,他引:1
目的观察补硒对正常鸡胚脑谷胱甘肽过氧化物酶(GPx)、Ⅱ型脱碘酶(IDⅡ)活性和生长相关蛋白(GAP-43)表达的影响,探讨硒对正常动物脑发育的作用。方法对孵育8 d的鸡胚分别注射不同剂量的MSeC(含0、1、5、10、20、40 μg硒),孵育至第20天时处死。测定脑组织中硒、GPx活性、IDⅡ活性,检测GAP-43蛋白的表达。结果对正常鸡胚补硒,可提高脑硒水平、脑GPx活性及GAP-43的表达,补硒量与脑硒、脑GPx活性显著相关(P< 0.01),而与脑IDⅡ活性无相关性。结论MSeC可有效提高鸡胚脑组织硒水平、脑GPx活性和GAP-43的表达,对脑IDⅡ活性没有影响。对正常鸡胚适量补硒可能会促进神经系统的生长和发育。 相似文献
75.
The 2004 Canadian recommendations for the management of hypertension: Part III--Lifestyle modifications to prevent and control hypertension 总被引:1,自引:0,他引:1
Touyz RM Campbell N Logan A Gledhill N Petrella R Padwal R;Canadian Hypertension Education Program 《The Canadian journal of cardiology》2004,20(1):55-59
OBJECTIVE: To provide updated, evidence-based recommendations regarding the role of lifestyle modification in the treatment and prevention of hypertension. OUTCOMES: Lifestyle modification interventions including exercise, weight reduction, alcohol consumption, dietary modification, intake of dietary cations and stress management are reviewed. Antioxidants and fish oil supplements are also reviewed, although specific recommendations cannot be made at present. EVIDENCE: MEDLINE searches were conducted from January 2002 to September 2003 to update the 2001 recommendations for the management of hypertension. Supplemental searches in the Cochrane Collaboration databases were also performed. Reference lists were scanned, experts were contacted, and the personal files of the subgroup members and authors were used to identify additional published studies. All relevant articles were reviewed and appraised independently using prespecified levels of evidence by content and methodology experts. RECOMMENDATIONS: Key recommendations include the following: lifestyle modification should be extended to nonhypertensive individuals who are at risk for developing high blood pressure; 30 min to 45 min of aerobic exercise should be performed on most days (four to five days) of the week; an ideal body weight (body mass index 18.5 kg/m2 to 24.9 kg/m2) should be maintained and weight loss strategies should use a multidisciplinary approach; alcohol consumption should be limited to two drinks or fewer per day, and weekly intake should not exceed 14 standard drinks for men and nine standard drinks for women; a reduced fat, low cholesterol diet that emphasizes fruits, vegetables and low fat dairy products, and maintains an adequate intake of potassium, magnesium and calcium, should be followed; salt intake should be restricted to 65 mmol/day to 100 mmol/day in hypertensive individuals and less than 100 mmol/day in normotensive individuals at high risk for developing hypertension; and stress management should be considered as an intervention in selected individuals. VALIDATION: All recommendations were graded according to the strength of the evidence and voted on by the Canadian Hypertension Education Program Evidence-Based Recommendations Task Force. Individuals with irreconcilable competing interests (declared by all members, compiled and circulated before the meeting) relative to any specific recommendation were excluded from voting on that recommendation. Only those recommendations achieving at least 70% consensus are reported here. These guidelines will continue to be updated annually. 相似文献
76.
Leukemia inhibitory factor induces neurotransmitter switching in transgenic mice. 总被引:5,自引:2,他引:5
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B A Bamber B A Masters G W Hoyle R L Brinster R D Palmiter 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(17):7839-7843
Leukemia inhibitory factor (LIF) is a cytokine growth factor that induces rat sympathetic neurons to switch their neurotransmitter phenotype from noradrenergic to cholinergic in vitro. To test whether LIF can influence neuronal differentiation in vivo, we generated transgenic mice that expressed LIF in pancreatic islets under the control of the insulin promoter and evaluated the neurotransmitter phenotype of the pancreatic sympathetic innervation. We also used the insulin promoter to coexpress nerve growth factor in the islets, which greatly increased the density of sympathetic innervation and facilitated analysis of the effects of LIF. Our data demonstrate that tyrosine hydroxylase and catecholamines declined and choline acetyltransferase increased in response to LIF. We conclude that LIF can induce neurotransmitter switching of sympathetic neurons in vivo. 相似文献
77.
78.
The Reactions of IgG and IgM Anti-A and Anti-B Blood Group Antibodies with 125 I-Labelled Blood Group Glycoproteins 总被引:1,自引:0,他引:1
Abstract. The reactions between IgG and IgM anti-A and anti-B and 125 I-labelled A and B blood group glycoproteins were investigated by a modification of the Farr technique. Inhibition curves obtained in a radioimmunoassay system indicate that IgM anti-A and anti-B antibodies have a significantly higher binding constant for A and B glycoproteins than IgG anti-A and anti-B. The observed difference in binding constant may explain the fact that A and B glycoproteins readily inhibit agglutination of A and B red cells by IgM anti-A and anti-B but less readily inhibit agglutination by IgG anti-A and anti-B. 相似文献
79.
Requirements of acetyl phosphate for the binding protein-dependent transport systems in Escherichia coli. 总被引:20,自引:3,他引:20
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J S Hong A G Hunt P S Masters M A Lieberman 《Proceedings of the National Academy of Sciences of the United States of America》1979,76(3):1213-1217
In Escherichia coli, acetyl phosphate can be formed from acetyl-CoA via the phosphotransacetylase (phosphate acetyltransferase; acetyl-CoA:orthophosphate acetyltransferase, EC 2.3.1.8) reaction and from acetate (plus ATP) via the acetate kinase (ATP:acetate phosphotransferase, EC 2.7.2.1) reaction. By restricting acetyl phosphate formation to the phosphotransacetylase reaction alone, through the use of metabolic inhibitors, we were able to show that, with pyruvate as a source of energy, mutants defective in phosphotransacetylase are unable to transport glutamine, histidine, and methionine. However, with the same energy source, mutants defective in acetate kinase are normal in the transport of these amino acids. The inability of the phosphotransacetylase mutants to transport is due to their presumed inability to form acetyl phosphate, because pyruvate is found to be metabolized to acetyl-CoA in these mutants. Thus acetyl phosphate has been implicated in active transport. Evidence is also presented that neither the protonmotive force nor the ecf gene product is required for the shock-sensitive transport systems. 相似文献
80.
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