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11.
Introduction
The percentage of neutrophils in sputum are increased in COPD patients, and may therefore be a biomarker of airway inflammation. We studied the relationships between sputum neutrophils and FEV1, health status, exacerbation rates, systemic inflammation and emphysema, and long term variability at 1 year.Methods
Sputum samples were obtained from 488 COPD patients within the ECLIPSE cohort. 359 samples were obtained at baseline, and 297 after 1 year. 168 subjects provided samples at both visits. Serum interleukin-6 (IL-6), IL-8, surfactant protein D and C-reactive protein levels were measured by immunoassays. Low-dose CT scans evaluated emphysema.Results
Sputum neutrophil % increased with GOLD stage. There was a weak association between % sputum neutrophils and FEV1 % predicted (univariate r2 = 0.025 and 0.094 at baseline and year 1 respectively, p < 0.05 after multivariate regression). Similar weak but significant associations were observed between neutrophil % and health status measured using the St Georges Respiratory Questionairre. There were no associations between neutrophils and exacerbation rates or emphysema. Associations between sputum neutrophils and systemic biomarkers were non-significant or similarly weak. The mean change over 1 year in neutrophil % was an increase of 3.5%.Conclusions
Sputum neutrophil measurements in COPD are associated weakly with FEV1 % predicted and health status. Sputum neutrophil measurements were dissociated from exacerbation rates, emphysema and systemic inflammation. 相似文献12.
Sanjay Dwivedi R. D. Tripathi Sudhakar Srivastava Ragini Singh Amit Kumar Preeti Tripathi Richa Dave U. N. Rai Debasis Chakrabarty P. K. Trivedi R. Tuli B. Adhikari M. K. Bag 《Protoplasma》2010,245(1-4):113-124
The exposure of paddy fields to arsenic (As) through groundwater irrigation is a serious concern that may not only lead to As accumulation to unacceptable levels but also interfere with mineral nutrients in rice grains. In the present field study, profiling of the mineral nutrients (iron (Fe), phosphorous, zinc, and selenium (Se)) was done in various rice genotypes with respect to As accumulation. A significant genotypic variation was observed in elemental retention on root Fe plaque and their accumulation in various plant parts including grains, specific As uptake (29–167 mg kg?1 dw), as well as As transfer factor (4–45%). Grains retained the least level of As (0.7–3%) with inorganic As species being the dominant forms, while organic As species, viz., dimethylarsinic acid and monomethylarsonic acid, were non-detectable. In all tested varieties, the level of Se was low (0.05–0.12 mg kg?1 dw), whereas that of As was high (0.4–1.68 mg kg?1 dw), considering their safe/recommended daily intake limits, which may not warrant their human consumption. Hence, their utilization may increase the risk of arsenicosis, when grown in As-contaminated areas. 相似文献
13.
Frank Boschelli Jennifer M. Golas Roseann Petersen Vincent Lau Lei Chen Diane Tkach Qiang Zhao Dave S. Fruhling Hao Liu Chaneun Nam Kim T. Arndt 《Cell stress & chaperones》2010,15(6):913-927
Cancer cells are exposed to external and internal stresses by virtue of their unrestrained growth, hostile microenvironment, and increased mutation rate. These stresses impose a burden on protein folding and degradation pathways and suggest a route for therapeutic intervention in cancer. Proteasome and Hsp90 inhibitors are in clinical trials and a 20S proteasome inhibitor, Velcade, is an approved drug. Other points of intervention in the folding and degradation pathway may therefore be of interest. We describe a simple screen for inhibitors of protein synthesis, folding, and proteasomal degradation pathways in this paper. The molecular chaperone-dependent client v-Src was fused to firefly luciferase and expressed in HCT-116 colorectal tumor cells. Both luciferase and protein tyrosine kinase activity were preserved in cells expressing this fusion construct. Exposing these cells to the Hsp90 inhibitor geldanamycin caused a rapid reduction of luciferase and kinase activities and depletion of detergent-soluble v-Src::luciferase fusion protein. Hsp70 knockdown reduced v-Src::luciferase activity and, when combined with geldanamycin, caused a buildup of v-Src::luciferase and ubiquitinated proteins in a detergent-insoluble fraction. Proteasome inhibitors also decreased luciferase activity and caused a buildup of phosphotyrosine-containing proteins in a detergent-insoluble fraction. Protein synthesis inhibitors also reduced luciferase activity, but had less of an effect on phosphotyrosine levels. In contrast, certain histone deacetylase inhibitors increased luciferase and phosphotyrosine activity. A mass screen led to the identification of Hsp90 inhibitors, ubiquitin pathway inhibitors, inhibitors of Hsp70/Hsp40-mediated refolding, and protein synthesis inhibitors. The largest group of compounds identified in the screen increased luciferase activity, and some of these increase v-Src levels and activity. When used in conjunction with appropriate secondary assays, this screen is a powerful cell-based tool for studying compounds that affect protein synthesis, folding, and degradation. 相似文献
14.
Niels Tørring Susan Ball Dave Wright Gaïané Sarkissian Marie Guitton Bruno Darbouret 《Reproductive biology and endocrinology : RB&E》2010,8(1):129
Background
A disintegrin and metalloprotease 12 (ADAM12-S) has previously been reported to be significantly reduced in maternal serum from women with fetal aneuploidy early in the first trimester and to significantly improve the quality of risk assessment for fetal trisomy 21 in prenatal screening. The aim of this study was to determine whether ADAM12-S is a useful serum marker for fetal trisomy 21 using the mixture model. 相似文献15.
Raciti D Reggiani L Geffers L Jiang Q Bacchion F Subrizi AE Clements D Tindal C Davidson DR Kaissling B Brändli AW 《Genome biology》2008,9(5):R84-21
Background
The pronephros, the simplest form of a vertebrate excretory organ, has recently become an important model of vertebrate kidney organogenesis. Here, we elucidated the nephron organization of the Xenopus pronephros and determined the similarities in segmentation with the metanephros, the adult kidney of mammals.Results
We performed large-scale gene expression mapping of terminal differentiation markers to identify gene expression patterns that define distinct domains of the pronephric kidney. We analyzed the expression of over 240 genes, which included members of the solute carrier, claudin, and aquaporin gene families, as well as selected ion channels. The obtained expression patterns were deposited in the searchable European Renal Genome Project Xenopus Gene Expression Database. We found that 112 genes exhibited highly regionalized expression patterns that were adequate to define the segmental organization of the pronephric nephron. Eight functionally distinct domains were discovered that shared significant analogies in gene expression with the mammalian metanephric nephron. We therefore propose a new nomenclature, which is in line with the mammalian one. The Xenopus pronephric nephron is composed of four basic domains: proximal tubule, intermediate tubule, distal tubule, and connecting tubule. Each tubule may be further subdivided into distinct segments. Finally, we also provide compelling evidence that the expression of key genes underlying inherited renal diseases in humans has been evolutionarily conserved down to the level of the pronephric kidney.Conclusion
The present study validates the Xenopus pronephros as a genuine model that may be used to elucidate the molecular basis of nephron segmentation and human renal disease. 相似文献16.
Wyatt PG Allen MJ Borthwick AD Davies DE Exall AM Hatley RJ Irving WR Livermore DG Miller ND Nerozzi F Sollis SL Szardenings AK 《Bioorganic & medicinal chemistry letters》2005,15(10):2579-2582
This paper covers efforts to discover orally active potent and selective oxytocin antagonists. Screening pooled libraries identified a novel series of 2,5-diketopiperazine derivatives with antagonist activity at the human oxytocin receptor. We report the initial structure-activity relationship investigations and the determination of the stereochemistry of the most potent compounds. 相似文献
17.
Thomas Southworth Andrew Higham Umme Kolsum Jian Li Thomas Scott Josiah Dungwa Sriram Sridhar Tuyet-Hang Pham Paul Newbold Dave Singh 《Journal of cellular and molecular medicine》2021,25(4):2203-2212
In chronic obstructive pulmonary disease (COPD), the effects of inhaled corticosteroids are predicted by blood eosinophil counts. We previously briefly reported increased immunoglobulin (Ig)A and IgM levels in bronchoalveolar lavage (BAL) of COPD patients with higher (eosinophilhigh) compared to lower (eosinophillow) blood eosinophils (>250/μL versus < 150/μL), suggesting differences in adaptive immune function. An inverse relationship exists between eosinophil counts and airway pathogenic bacteria levels. The mechanistic reasons for these associations between eosinophils, corticosteroids and pathogenic bacteria are unclear. IgA, IgM and IgG levels were assessed in BAL, bronchial biopsies and epithelium collected from eosinophilhigh (n = 20) and eosinophillow (n = 21) patients. Bronchial B-cell numbers were measured by immunohistochemistry. B-cell activity was assessed in bronchial samples and following exposure to BAL from eosinophilhigh and eosinophillow patients. BAL levels of non-typeable Haemophilus influenza (NTHi)-specific immunoglobulins were quantified. Results showed airway expression of IgA, IgG1 and IgM were lower in eosinophillow compared to eosinophilhigh patients, with lower levels of NTHi-specific IgA and IgM. Bronchial B-cell numbers were similar in both groups, but B-cell activity was lower in eosinophillow patients. In conclusion, COPD eosinophillow patients show differences in adaptive immune function compared to COPD eosinophilhigh patients. These differences may cause different microbiomes in these COPD phenotypes. 相似文献
18.
Dave S. B. Hoon Yoshihiko Hayashi Takashi Morisaki Leland J. Foshag Donald L. Morton 《Cancer immunology, immunotherapy : CII》1993,37(6):378-384
Immune cytokines are important regulators of the immune response to neoplastic cells. We previously reported that interleukin 4 (IL-4) and either tumor necrosis factor α (TNF) or interferon γ (IFN) synergistically inhibit melanoma cell growth and induce cell differentiation. In the present study we used various combinations of IL-4, IFN and TNF to enhance the antigenicity of melanoma cells. IL-4 plus TNF significantly increased the ability of melanoma cells to stimulate cytotoxic T cells (CTL) and act as targets of these CTL; IL-4 plus IFN was somewhat less effective, while TNF plus IFN was not as effective. IL-4 plus TNF also increased the expression of HLA class I and HLA-DR antigens on melanoma cells. The CTL lines examined in this study were CD3+CD4+ and oligoclonal. These preclinical results suggest that the immune response to melanoma whole-cell vaccines might be enhanced by pretreating vaccine cells with IL-4 plus TNF. 相似文献
19.
Paresh Vamanrao Dave Amar Niranjan Shah Pankaj B. Nimavat Bhavesh B. Modi Kirit R. Pujara Pradip Patel Keshabhai Mehariya Kiran Vaman Rade Soma Shekar Kuldeep S. Sachdeva John E. Oeltmann Ajay M. V. Kumar 《PloS one》2016,11(2)
Background
The World Health Organization recommends direct observation of treatment (DOT) to support patients with tuberculosis (TB) and to ensure treatment completion. As per national programme guidelines in India, a DOT provider can be anyone who is acceptable and accessible to the patient and accountable to the health system, except a family member. This poses challenges among children with TB who may be more comfortable receiving medicines from their parents or family members than from unfamiliar DOT providers. We conducted a non-inferiority trial to assess the effect of family DOT on treatment success rates among children with newly diagnosed TB registered for treatment during June–September 2012.Methods
We randomly assigned all districts (n = 30) in Gujarat to the intervention (n = 15) or usual-practice group (n = 15). Adult family members in the intervention districts were given the choice to become their child’s DOT provider. DOT was provided by a non-family member in the usual-practice districts. Using routinely collected clinic-based TB treatment cards, we compared treatment success rates (cured and treatment completed) between the two groups and the non-inferiority limit was kept at 5%.Results
Of 624 children with newly diagnosed TB, 359 (58%) were from intervention districts and 265 (42%) were from usual-practice districts. The two groups were similar with respect to baseline characteristics including age, sex, type of TB, and initial body weight. The treatment success rates were 344 (95.8%) and 247 (93.2%) (p = 0.11) among the intervention and usual-practice groups respectively.Conclusion
DOT provided by a family member is not inferior to DOT provided by a non-family member among new TB cases in children and can attain international targets for treatment success.Trial Registration
Clinical Trials Registry–India, National Institute of Medical Statistics (Indian Council of Medical Research) CTRI/2015/09/006229 相似文献20.
J. R. Ryan K. Dave E. Emmerich L. Garcia L. Yi R. E. Coleman J. Sattabongkot R. F. Dunton A. S. T. Chan R. A. Wirtz 《Medical and veterinary entomology》2001,15(2):225-230
Malaria remains the most serious vector-borne disease, affecting some 300-500 million people annually, transmitted by many species of Anopheles mosquitoes (Diptera: Culicidae). Monoclonal antibodies developed against specific circumsporozoite (CS) proteins of the main malaria parasites Plasmodium falciparum and P. vivax have been used previously for enzyme-linked immunosorbent assays (ELISA), widely employed for detection of malaria sporozoites in vector Anopheles for local risk assessment, epidemiological studies and targeting vector control. However, ELISA procedures are relatively slow and impractical for field use. To circumvent this, we developed rapid wicking assays that identify the presence or absence of specific peptide epitopes of CS protein of the most important P. falciparum and two strains (variants 210 and 247) of the more widespread P. vivax. The resulting assay is a rapid, one-step procedure using a 'dipstick' wicking test strip. In laboratory assessment, dipsticks identified 1 ng/ mL of any of these three CS protein antigens, with sensitivity nearly equal to the CS standard ELISA. We have developed and are evaluating a combined panel assay that will be both qualitative and quantitative. This quick and easy dipstick test (VecTest Malaria) offers practical advantages for field workers needing to make rapid surveys of malaria vectors. 相似文献