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51.
Hematopoietic growth factors not only modulate blood progenitor cell activity but also alter the function of mature phagocytes. Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF; 1 ng/mL for 60 min) did not stimulate luminol-enhanced chemiluminescence of polymorphonuclear leukocytes (PMNs) in suspension but primed PMN for as much as a 15-fold increase in chemiluminescence in response to f-met- leu-phe (fMLP). Mixed mononuclear leukocytes (monocytes [approximately 20%] and lymphocytes [approximately 80%]; MNL) chemiluminescence was very low even after rhGM-CSF priming, but MNLs added to the PMNs (PMN- MNL) resulted in near doubling of rhGM-CSF-primed PMN fMLP-stimulated chemiluminescence. The enhancing factor(s) from MNLs were inherent rather than induced by the GM-CSF, and purified lymphocytes increased GM-CSF-primed PMN chemiluminescence equal to mixed MNLs. We could not detect cell-free "enhancing factor(s)," but cell-to-cell contact further enhanced rhGM-CSF-primed fMLP-stimulated PMN-MNL oxidative activity by 40%. Polyclonal rabbit anti-tumor necrosis factor (TNF) (but not preimmune serum) decreased both fMLP-stimulated rhGM-CSF- primed PMNs and PMN-MNL chemiluminescence, suggesting that TNF on the PMN surface is enhancing GM-CSF-primed chemiluminescence. GM-CSF priming markedly increased PMN superoxide release (sevenfold), but PMN superoxide release was not further enhanced by the presence of MNLs. Recombinant human granulocyte colony-stimulating factor (rhG-CSF) and interleukin-3 (rhIL-3) displayed much smaller effects on pure PMNs and mixed PMN-MNL chemiluminescence and superoxide release than rhGM-CSF. rhGM-CSF primes PMNs for increased oxidative activity more than rhG-CSF and rhIL-3. Maximal oxidative activity was observed when mixed PMN-MNL were primed with GM-CSF in a cell pellet-promoting cell-to-cell contact. This enhanced activity can be attributed, in part, to both inherent enhancing factor(s) on lymphocytes and PMN-associated TNF induced by GM-CSF. 相似文献
52.
File TM Garau J Blasi F Chidiac C Klugman K Lode H Lonks JR Mandell L Ramirez J Yu V 《Chest》2004,125(5):1888-1901
Empiric antimicrobial prescribing for community-acquired pneumonia remains a challenge, despite the availability of treatment guidelines. A number of key differences exist between North American and European guidelines, mainly in the outpatient setting. The North American approach is to use initial antimicrobial therapy, which provides coverage for Streptococcus pneumoniae plus atypical pathogens. Europeans tend to focus on providing pneumococcal coverage with less emphasis on covering for an atypical pathogen. Ambulatory patients without comorbidity are more likely to receive macrolide therapy in North America, whereas in Europe these patients would probably receive a beta-lactam agent. Major issues that are fundamental to this difference include the importance of providing therapy for atypical pathogens and the clinical significance of macrolide-resistant S pneumoniae. Prospective data are required to evaluate which of these two approaches offers clinical superiority. 相似文献
53.
Gout is a chronic, potentially debilitating condition characterized by an inflammatory process in the joints or periarticular tissues that results from the deposition of monosodium urate crystals. Underdiagnosis and undertreatment can lead to the development of tophi and chronic arthropathy. A presumptive diagnosis of gout can be made on the basis of the clinical presentation as well as risk factors such as metabolic syndrome. Key conditions to rule out in the differential diagnosis are septic arthritis, calcium pyrophosphate deposition disease (pseudogout), fracture, and rheumatoid arthritis. Acute flares of gout should be managed with nonsteroidal antiinflammatory drugs (NSAIDs), colchicine, or corticosteroids. With a diagnosis of gout, if urate-lowering therapy (ULT) is required, prophylaxis should be considered with low-dose colchicine or an NSAID, followed by the addition of ULT. The goal of ULT is to reach a serum uric acid (SUA) level ≤6.0 mg/dL. Measurements of SUA should be obtained after resolution of an acute attack, then periodically to facilitate titration of the ULT dose to achieve the target SUA level. Studies have confirmed significant reductions in gout attacks among patients who have attained SUA levels ≤6.0 mg/dL with ULT. Patient education concerning the disease and its treatment is essential to ensure close adherence with recommended therapies. Patients should also understand that ULT is intended as long-term, and for most patients, lifelong therapy to maximize the prospects for control of the disease. Clinicians should feel confident in making a presumptive diagnosis and choosing a therapeutic regimen for gout while effectively communicating with and educating patients about their disease. 相似文献
54.
Jessica Suhrheinrich Aubyn C. Stahmer Sarah Reed Laura Schreibman Erica Reisinger David Mandell 《Journal of autism and developmental disorders》2013,43(12):2970-2976
Implementing evidence-based practices (EBPs) for children with autism is challenging for teachers because these practices are often complex, requiring significant training and resources that are not available in most school settings. This brief investigation was designed to identify areas of strength and difficulty for teachers implementing one such EBP, pivotal response training (PRT). Observational data were gathered from 41 teachers participating in two separate investigations involving PRT. Despite differences in training procedures, teachers demonstrated similarities in areas of strength (clear opportunities/instruction and child choice) and difficulty (turn taking and multiple cues). These findings suggest next steps toward systematic adaptation of PRT for classroom use. The research may serve as a model for the process of adapting EBPs for practice settings. 相似文献
55.
Liu Guodong Velott Diana L. Kong Lan Dick Andrew W. Mandell David S. Stein Bradley D. Murray Michael J. Ba Djibril M. Cidav Zuleyha Leslie Douglas L. 《Journal of autism and developmental disorders》2022,52(4):1587-1597
Journal of Autism and Developmental Disorders - Using the 2008–2013 Medicaid Analytic eXtract files, this retrospective cohort study was to evaluate the effect of Medicaid home and... 相似文献
56.
57.
Chan KS Wenzel S Orlando M Montagnet C Mandell W Becker K Ebener P 《The American journal of drug and alcohol abuse》2004,30(4):871-891
Prior research has demonstrated that therapeutic communities (TCs) are effective at improving posttreatment outcomes for substance abusers. However, little is known about the in-treatment experience for clients with different backgrounds, experiences, and needs. The aim of this study is to examine the in-treatment experience for different clients by exploring the relationships between treatment process and client characteristics. A comprehensive measure of treatment process, operationalized as Community Environment and Personal Change and Development and change was administered to 447 adults and 148 adolescents receiving treatment at community-based TC programs in New York, California, and Texas. Data on demographic characteristics, substance use and treatment history, and client risk factors were extracted from intake interviews and analyzed separately for adolescent and adult residents. Multivariate general linear models were used to examine the effect of client variables on treatment process, after controlling for treatment duration and program effects. Within adult programs, clients who were 25 years or older, female, and had a prior drug treatment experience had higher Community Environment scores. Adolescents with one or more arrests within the past 2 years had lower scores on both process dimensions of Community Environment and Personal Development and Change. Our results indicate the need to understand why adult clients who are younger, male, and have no prior treatment history and adolescent clients with recent arrests reported lower ratings of treatment process. Future research should also examine the role of modifiable mediators so that appropriate strategies to enhance therapeutic engagement may be developed as necessary. 相似文献
58.
Multiple signal transduction cascades, consisting of multiple interacting proteins, are activated following stimulation through most cell surface receptors, including the immunoglobulin receptor of B lymphocytes. In this report, we investigated the multimolecular complexes formed following anti-Ig stimulation of a human B-lymphoma cell line, resulting in activation of phosphatidylinositol 3-kinase (PI3K). PI3K is a lipid kinase that consists of an 85-kD regulatory subunit, bound to a 110-kD catalytic subunit. CD19 is a 95-kD B-cell surface marker that contains a consensus binding motif for PI3Kp85 in the cytoplasmic domain and recruits PI3K activity in activated B cells. The protein product of the c-cbl protooncogene is a 120-kD protein that is expressed in early B-lineage cells and in myeloid cells and is phosphorylated on tyrosine following receptor-mediated signaling in T and B lymphocytes. We demonstrate here that phosphorylated c-cbl complexes with CD19 and with PI3Kp85 via its C-terminal SH2 domain, and that both c-cbl and CD19 are associated with active PI3K in anti-Ig- stimulated cells. Although we cannot differentiate between a three- component, c-cbl/CD19/p85 complex and individual two-component complexes, these studies suggest that c-cbl may function as a docking protein, possibly linking distinct signal transduction pathways. 相似文献
59.
Protein-tyrosine kinase p72syk in Fc gamma RI receptor signaling 总被引:2,自引:1,他引:2
In this report we show that gamma-interferon (IFN) induces the expression of the nonreceptor protein tyrosine kinase, p72syk, and that cross-linking the Fc gamma RI receptor in IFN-differentiated U937 cells (U937IF cells) results in the activation of syk kinase. We show that syk is tyrosine phosphorylated (12-fold increase) after Fc gamma RI cross-linking. In vitro kinase assays demonstrate that the specific kinase activity of syk increased eightfold after Fc gamma RI cross- linking. The activation of signal transduction through the Fc gamma RI receptor, as measured by the respiratory burst, is associated with the tyrosine phosphorylation and catalytic activation of the syk kinase. We show that syk coprecipitates with the gamma subunit of the Fc gamma RI, Fc gamma RI gamma. The data suggest that p72syk is involved in signal transduction through the Fc gamma RI receptor, involving the Fc gamma RI gamma subunit. 相似文献
60.
Maternal administration of granulocyte colony-stimulating factor improves neonatal rat survival after a lethal group B streptococcal infection 总被引:2,自引:0,他引:2
Novales JS; Salva AM; Modanlou HD; Kaplan DL; del Castillo J; Andersen J; Medlock ES 《Blood》1993,81(4):923-927
Maternally administered recombinant human granulocyte colony- stimulating factor (rhG-CSF) has been shown to cross the placenta and induce a peripheral neutrophilia and increases in the marrow and spleen neutrophil storage pools in fetal and newborn rats. In the present study, we have used this model system to investigate the efficacy of prenatally administered rhG-CSF on neonatal defense to a lethal challenge with Group B-beta hemolytic Streptococcus (GBS). Pregnant rats were injected with rhG-CSF twice daily beginning 6 days before parturition. At birth, all pups were infected with a dose of GBS that is lethal for 90% of infected pups (LD90). Survival was monitored daily for 5 days. Survival of infected pups from saline-treated mothers beyond 60 hours after infection was 10%. No difference in survival was observed among pups from mothers treated 2 and 4 days before parturition. In contrast, we determined that survival was 82.5% among infected pups from mothers treated for 6 days before parturition with rhG-CSF. Our results demonstrate that maternal administration of rhG- CSF augments neonatal defenses against a lethal bacterial challenge. 相似文献