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41.
42.
Albert L Sheffer Mike Silverman Ann J Woolcock Patricia V Díaz Bengt Lindberg Bertil Lindmark 《Annals of allergy, asthma & immunology》2005,94(1):48-54
BACKGROUND: The Inhaled Steroid Treatment as Regular Therapy in Early Asthma (START) study is a worldwide, randomized, prospective study to investigate early intervention with inhaled corticosteroids in recent-onset mild persistent asthma. OBJECTIVE: To evaluate the safety and tolerability of long-term treatment with once-daily budesonide therapy in patients with mild persistent asthma. METHODS: Patients aged 5 to 66 years with mild persistent asthma for fewer than 2 years and no previous regular corticosteroid treatment received budesonide or placebo once daily for 3 years, in addition to their usual asthma therapy. The daily budesonide dose was 200 microg for children younger than 11 years and 400 microg for those 11 years or older. RESULTS: Overall, 7,221 patients were included in the safety analysis, and a total of 21,520 adverse events were reported (10,850 in the budesonide group and 10,670 in the placebo group). The most commonly reported events included respiratory infections, rhinitis, pharyngitis, bronchitis, viral infections, and sinusitis. The number of deaths and serious adverse events were similar for children and adults in both treatment groups. Fewer asthma-related serious adverse events were reported with budesonide (162) compared with placebo (276). Oral candidiasis was reported more frequently with budesonide (1.2%) than with placebo (0.5%); the frequencies of other adverse effects previously reported to be associated with inhaled corticosteroids (psychiatric disorders, skin disorders, and allergic reactions) were similar. CONCLUSIONS: Three-year treatment with budesonide once daily (200 or 400 microg) is safe and well tolerated in children and adults with newly detected mild persistent asthma. 相似文献
43.
Systemically administered DNA encoding a recombinant human immunodeficiency virus (HIV) derived immunogen effectively primes a cytotoxic T lymphocyte (CTL) response in macaques. In this further pilot study we have evaluated mucosal delivery of DNA as an alternative priming strategy. Plasmid DNA, pTH.HW, encoding a multi-CTL epitope gene, was incorporated into poly(D,L-lactic-co-glycolic acid) microparticles of less than 10 microm in diameter. Five intrarectal immunizations failed to stimulate a circulating vaccine-specific CTL response in 2 Mamu-A*01(+) rhesus macaques. However, 1 week after intradermal immunization with a cognate modified vaccinia virus Ankara vaccine MVA.HW, CTL responses were detected in both animals that persisted until analysis postmortem, 12 weeks after the final boost. In contrast, a weaker and less durable response was seen in an animal vaccinated with the MVA construct alone. Analysis of lymphoid tissues revealed a disseminated CTL response in peripheral and regional lymph nodes but not the spleen of both mucosally primed animals. 相似文献
44.
Adjuvant-dependent modulation of Th1 and Th2 responses to immunization with beta-amyloid 总被引:6,自引:0,他引:6
Cribbs DH Ghochikyan A Vasilevko V Tran M Petrushina I Sadzikava N Babikyan D Kesslak P Kieber-Emmons T Cotman CW Agadjanyan MG 《International immunology》2003,15(4):505-514
The role of adjuvant on the T(h)1 and T(h)2 immune responses to Abeta-immunotherapy (Abeta(42 )peptide) was examined in wild-type mice. Fine epitope analysis with overlapping oligomers of the Abeta(42) sequence identified the 1-15 region as a dominant B cell epitope. The 6-20 peptide was recognized only weakly by antisera from mice administrated with Abeta(42) peptide formulated in complete Freund's adjuvant (CFA), alum or TiterMax Gold (TMG). However, mice immunized with Abeta(42) mixed with QS21 induced a significant antibody response to the 6-20 peptide. The only T cell epitope found was within the 6-28 sequence of Abeta(42). QS21 and CFA induced the strongest humoral response to Abeta, alum was intermediate, and TMG the weakest adjuvant. Analysis of antibody isotypes specific for Abeta indicates that alum induces primarily T(h)2-type immune response, whereas TMG, CFA and QS21 shift the immune responses toward a T(h)1 phenotype. Stimulation of splenocytes from Abeta-immunized mice with Abeta(40) peptide induced strikingly different cytokine expression profiles. QS21 and CFA induced significant IFN-gamma, IL-4 and tumor necrosis factor-alpha expression, whereas alum induced primarily IL-4 production. As T(h)1-type immune responses have been implicated in many autoimmune disorders, whereas T(h)2-type responses have been shown to inhibit autoimmune disease, the choice of adjuvant may be critical for the design of a safe and effective immunotherapy for Alzheimer's disease. 相似文献
45.
Plunkett FJ Franzese O Belaramani LL Fletcher JM Gilmour KC Sharifi R Khan N Hislop AD Cara A Salmon M Gaspar HB Rustin MH Webster D Akbar AN 《Mechanisms of ageing and development》2005,126(8):855-865
Patients with X-linked lymphoproliferative syndrome (XLP) experience excessive T cell proliferation after primary Epstein-Barr virus (EBV) infection, due to mutations in the signalling lymphocyte activation molecule (SLAM) associated protein (SAP) molecule. We examined the impact of dysfunctional proliferative control on the extent of CD8+ T cell differentiation in XLP patients who recovered from primary EBV infection. Although these young patients have normal numbers of lytic and latent EBV-epitope-specific CD8+ T cells, they were extremely differentiated as defined by loss of CCR7 and CD27, low telomerase activity and very short telomeres. This was not a direct effect arising from the loss of SAP, but was due to excessive T cell stimulation due to this defect. Thus, transduction of XLP CD8+ T cells with the catalytic component of telomerase (hTERT), but not SAP, prevented telomere loss and considerably extended proliferative lifespan in vitro. These results indicate that excessive proliferation in CD8+ T cells in XLP patients may lead to end-stage differentiation and loss of functional EBV-specific CD8+ T cells through replicative senescence. This may contribute to the defective immunity found in XLP patients who survive acute EBV infection who develop EBV-related B cell lymphomas before the fourth decade of life. 相似文献
46.
47.
Rudy G E van Eijsden Mike Gerards Lars M T Eijssen Alexandra T M Hendrickx Roselie J E Jongbloed John H J Wokke Rogier Q Hintzen Maria E Rubio-Gozalbo Irenaeus F M De Coo Egill Briem Valeria Tiranti Hubert J M Smeets 《Genetics in medicine》2006,8(10):620-627
PURPOSE: Oxidative phosphorylation is under dual genetic control of the nuclear and the mitochondrial DNA (mtDNA). Oxidative phosphorylation disorders are clinically and genetically heterogeneous, which makes it difficult to determine the genetic defect, and symptom-based protocols which link clinical symptoms directly to a specific gene or mtDNA mutation are falling short. Moreover, approximately 25% of the pediatric patients with oxidative phosphorylation disorders is estimated to have mutations in the mtDNA and a standard screening approach for common mutations and deletions will only explain part of these cases. Therefore, we tested a new CHIP-based screening method for the mtDNA. METHODS: MitoChip (Affymetrix) resequencing was performed on three test samples and on 28 patient samples. RESULTS: Call rates were 94% on average and heteroplasmy detection levels varied from 5-50%. A genetic diagnosis can be made in almost one-quarter of the patients at a potential output of 8 complete mtDNA sequences every 4 days. Moreover, a number of potentially pathogenic unclassified variants (UV) were detected. CONCLUSIONS: The availability of long-range PCR protocols and the predominance of single nucleotide substitutions in the mtDNA make the resequencing CHIP a very fast and reliable method to screen the complete mtDNA for mutations. 相似文献
48.
Remodeling of the chromatin network plays an important role regulating embryonic development as well as differentiation. The SWI/SNF complex is an ATP-dependent chromatin-remodeling complex. It consists of several proteins, including an ATPase subunit, either Brg1 or Brm. Two subunits of this complex, Baf53a and Baf45, have been previously identified as being neural progenitor-specific. In this study, we show that Baf60c, another important part of this large complex, acts in a similar neural progenitor-specific manner. We show that during development Baf60c is expressed in neural progenitors in human retinas as well as mouse retina, cortex and spinal cord. Baf60c expression is lost during neural differentiation and its overexpression keeps the progenitors in a proliferative state through its interaction with the Notch pathway. Finally, we show that Baf60c is re-expressed in the Müller glial cells that re-enter the cell cycle after neurotoxic damage. 相似文献
49.
Nina Yao Jennifer Turner Zvi Kelman P. Todd Stukenberg Frank Dean David Shechter Zhen-Qiang Pan Jerard Hurwitz Mike O'Donnell 《Genes to cells : devoted to molecular & cellular mechanisms》1996,1(1):101-113
Background: The high speed and processivity of replicative DNA polymerases reside in a processivity factor which has been shown to be a ring-shaped protein. This protein (‘sliding clamp’) encircles DNA and tethers the catalytic unit to the template. Although in eukaryotic, prokaryotic and bacteriophage-T4 systems, the processivity factors are ring-shaped, they assume different oligomeric states. The Escherichia coli clamp (the β subunit) is active as a dimer while the eukaryotic and T4 phage clamps (PCNA and gp45, respectively) are active as trimers. The clamp can not assemble itself on DNA. Instead, a protein complex known as a clamp loader utilizes ATP to assemble the ring around the primer-template. This study compares properties of the human PCNA clamp with those of E. coli and T4 phage. Results: The PCNA ring is a stable trimer down to a concentration below 100 nm (Kd ≈ 21 nm ). On DNA, the PCNA clamp slides freely and dissociates from DNA slowly (t1/2 ≈ 24 min). β is more stable in solution (Kd < 60 pm ) and on DNA (t1/2 ≈ 1 h) than PCNA which may be explained by its simpler oligomeric state. The T4 gp45 clamp is a much less stable trimer than PCNA (Kd ≈ 250 nm ) and requires association with the polymerase to stabilize it on DNA as observed previously. The consequence of this cooperation between clamp and polymerase is that upon finishing a template and dissociation of the polymerase from DNA, the gp45 clamp spontaneously dissociates from DNA without assistance. However, the greater stability of the PCNA and β clamps on DNA necessitates an active process for their removal. The clamp loaders (RF-C and γ complex) were also capable of unloading their respective clamps from DNA in the presence of ATP. Conclusions: The stability of the different clamps in solution correlates with their stability on DNA. Thus, the low stability of the T4 clamp explains the inability to isolate gp45 on DNA. The stability of the PCNA and β clamps predicts they will require an unloading factor to recycle them on and off DNA during replication. The clamp loaders of PCNA and β double as clamp unloaders presumably for the purpose of clamp recycling. 相似文献
50.