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991.
Automated pipeline for rapid production and screening of HIV‐specific monoclonal antibodies using pichia pastoris
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992.
Alison D. Gernand Kerry J. Schulze Ashika Nanayakkara-Bind Margia Arguello Abu Ahmed Shamim Hasmot Ali Lee Wu Keith P. West Jr. Parul Christian 《PloS one》2015,10(10)
Prenatal multiple micronutrient (MM) supplementation improves birth weight through increased fetal growth and gestational age, but whether maternal or fetal growth factors are involved is unclear. Our objective was to examine the effect of prenatal MM supplementation on intrauterine growth factors and the associations between growth factors and birth outcomes in a rural setting in Bangladesh. In a double-blind, cluster-randomized, controlled trial of MM vs. iron and folic acid (IFA) supplementation, we measured placental growth hormone (PGH) at 10 weeks and PGH and human placental lactogen (hPL) at 32 weeks gestation in maternal plasma (n = 396) and insulin, insulin-like growth factor-1 (IGF-1), and IGF binding protein-1 (IGFBP-1) in cord plasma (n = 325). Birth size and gestational age were also assessed. Early pregnancy mean (SD) BMI was 19.5 (2.4) kg/m2 and birth weight was 2.68 (0.41) kg. There was no effect of MM on concentrations of maternal hPL or PGH, or cord insulin, IGF-1, or IGFBP-1. However, among pregnancies of female offspring, hPL concentration was higher by 1.1 mg/L in the third trimester (95% CI: 0.2, 2.0 mg/L; p = 0.09 for interaction); and among women with height <145 cm, insulin was higher by 59% (95% CI: 3, 115%; p = 0.05 for interaction) in the MM vs. IFA group. Maternal hPL and cord blood insulin and IGF-1 were positively, and IGFBP-1 was negatively, associated with birth weight z score and other measures of birth size (all p<0.05). IGF-1 was inversely associated with gestational age (p<0.05), but other growth factors were not associated with gestational age or preterm birth. Prenatal MM supplementation had no overall impact on intrauterine growth factors. MM supplementation altered some growth factors differentially by maternal early pregnancy nutritional status and sex of the offspring, but this should be examined in other studies.
Trial Registration
ClinicalTrials.gov NCT00860470 相似文献993.
Alexandra Pender Isaac Garcia-Murillas Sareena Rana Rosalind J. Cutts Gavin Kelly Kerry Fenwick Iwanka Kozarewa David Gonzalez de Castro Jaishree Bhosle Mary O’Brien Nicholas C. Turner Sanjay Popat Julian Downward 《PloS one》2015,10(9)
Droplet digital PCR (ddPCR) can be used to detect low frequency mutations in oncogene-driven lung cancer. The range of KRAS point mutations observed in NSCLC necessitates a multiplex approach to efficient mutation detection in circulating DNA. Here we report the design and optimisation of three discriminatory ddPCR multiplex assays investigating nine different KRAS mutations using PrimePCR™ ddPCR™ Mutation Assays and the Bio-Rad QX100 system. Together these mutations account for 95% of the nucleotide changes found in KRAS in human cancer. Multiplex reactions were optimised on genomic DNA extracted from KRAS mutant cell lines and tested on DNA extracted from fixed tumour tissue from a cohort of lung cancer patients without prior knowledge of the specific KRAS genotype. The multiplex ddPCR assays had a limit of detection of better than 1 mutant KRAS molecule in 2,000 wild-type KRAS molecules, which compared favourably with a limit of detection of 1 in 50 for next generation sequencing and 1 in 10 for Sanger sequencing. Multiplex ddPCR assays thus provide a highly efficient methodology to identify KRAS mutations in lung adenocarcinoma. 相似文献
994.
Tess Harris Sally M. Kerry Christina R. Victor Ulf Ekelund Alison Woodcock Steve Iliffe Peter H. Whincup Carole Beighton Michael Ussher Elizabeth S. Limb Lee David Debbie Brewin Fredrika Adams Annabelle Rogers Derek G. Cook 《PLoS medicine》2015,12(2)
Background
Brisk walking in older people can increase step-counts and moderate to vigorous intensity physical activity (MVPA) in ≥10-minute bouts, as advised in World Health Organization guidelines. Previous interventions have reported step-count increases, but not change in objectively measured MVPA in older people. We assessed whether a primary care nurse-delivered complex intervention increased objectively measured step-counts and MVPA.Methods and Findings
A total of 988 60–75 year olds, able to increase walking and randomly selected from three UK family practices, were invited to participate in a parallel two-arm cluster randomised trial; randomisation was by household. Two-hundred-ninety-eight people from 250 households were randomised between 2011 and 2012; 150 individuals to the intervention group, 148 to the usual care control group. Intervention participants received four primary care nurse physical activity (PA) consultations over 3 months, incorporating behaviour change techniques, pedometer step-count and accelerometer PA intensity feedback, and an individual PA diary and plan. Assessors were not blinded to group status, but statistical analyses were conducted blind. The primary outcome was change in accelerometry assessed average daily step-counts between baseline and 3 months, with change at 12 months a secondary outcome. Other secondary outcomes were change from baseline in time in MVPA weekly in ≥10-minute bouts, accelerometer counts, and counts/minute at 3 months and 12 months. Other outcomes were adverse events, anthropometric measures, mood, and pain. Qualitative evaluations of intervention participants and practice nurses assessed the intervention’s acceptability. At 3 months, eight participants had withdrawn or were lost to follow-up, 280 (94%) individuals provided primary outcome data. At 3 months changes in both average daily step-counts and weekly MVPA in ≥10-minute bouts were significantly higher in the intervention than control group: by 1,037 (95% CI 513–1,560) steps/day and 63 (95% CI 40–87) minutes/week, respectively. At 12 months corresponding differences were 609 (95% CI 104–1,115) steps/day and 40 (95% CI 17–63) minutes/week. Counts and counts/minute showed similar effects to steps and MVPA. Adverse events, anthropometry, mood, and pain were similar in the two groups. Participants and practice nurses found the intervention acceptable and enjoyable.Conclusions
The PACE-Lift trial increased both step-counts and objectively measured MVPA in ≥10-minute bouts in 60–75 year olds at 3 and 12 months, with no effect on adverse events. To our knowledge, this is the first trial in this age group to demonstrate objective MVPA increases and highlights the value of individualised support incorporating objective PA assessment in a primary care setting.Trial Registration
Controlled-Trials.com ISRCTN42122561 相似文献995.
Alvarez-Curto E Saran S Meima M Zobel J Scott C Schaap P 《Development (Cambridge, England)》2007,134(5):959-966
Encystation and sporulation are crucial developmental transitions for solitary and social amoebae, respectively. Whereas little is known of encystation, sporulation requires both extra- and intracellular cAMP. After aggregation of social amoebae, extracellular cAMP binding to surface receptors and intracellular cAMP binding to cAMP-dependent protein kinase (PKA) act together to induce prespore differentiation. Later, a second episode of PKA activation triggers spore maturation. Adenylyl cyclase B (ACB) produces cAMP for maturation, but the cAMP source for prespore induction is unknown. We show that adenylyl cyclase G (ACG) protein is upregulated in prespore tissue after aggregation. acg null mutants show reduced prespore differentiation, which becomes very severe when ACB is also deleted. ACB is normally expressed in prestalk cells, but is upregulated in the prespore region of acg null structures. These data show that ACG induces prespore differentiation in wild-type cells, with ACB capable of partially taking over this function in its absence. 相似文献
996.
Kogelberg H Tolner B Sharma SK Lowdell MW Qureshi U Robson M Hillyer T Pedley RB Vervecken W Contreras R Begent RH Chester KA 《Glycobiology》2007,17(1):36-45
MFECP1 is a mannosylated antibody-enzyme fusion protein used in antibody-directed enzyme prodrug therapy (ADEPT). The antibody selectively targets tumor cells and the targeted enzyme converts a prodrug into a toxic drug. MFECP1 is obtained from expression in the yeast Pichia pastoris and produced to clinical grade. The P. pastoris-derived mannosylation of the fusion protein aids rapid normal tissue clearance required for successful ADEPT. The work presented provides evidence that MFECP1 is cleared by the endocytic and phagocytic mannose receptor (MR), which is known to bind to mannose-terminating glycans. MR-transfected fibroblast cells internalize MFECP1 as revealed by flow cytometry and confocal microscopy. Immunofluorescence microscopy shows that in vivo clearance in mice occurs predominantly by MR on liver sinusoidal endothelial cells, although MR is also expressed on adjacent Kupffer cells. In the spleen, MFECP1 is taken up by MR-expressing macrophages residing in the red pulp and not by dendritic cells which are found in the marginal zone and white pulp. Clearance can be inhibited in vivo by the MR inhibitor mannan as shown by increased enzyme activities in blood. The work improves understanding of interactions of MFECP1 with normal tissue, shows that glycosylation can be exploited in the design of recombinant anticancer therapeutics and opens the ways for optimizing pharmacokinetics of mannosylated recombinant therapeutics. 相似文献
997.
Dwyer MP Paruch K Alvarez C Doll RJ Keertikar K Duca J Fischmann TO Hruza A Madison V Lees E Parry D Seghezzi W Sgambellone N Shanahan F Wiswell D Guzi TJ 《Bioorganic & medicinal chemistry letters》2007,17(22):6216-6219
A series of four bicyclic cores were prepared and evaluated as cyclin-dependent kinase-2 (CDK2) inhibitors. From the in-vitro and cell-based analysis, the pyrazolo[1,5-a]pyrimidine core (represented by 9) emerged as the superior core for further elaboration in the identification of novel CDK2 inhibitors. 相似文献
998.
Paruch K Dwyer MP Alvarez C Brown C Chan TY Doll RJ Keertikar K Knutson C McKittrick B Rivera J Rossman R Tucker G Fischmann TO Hruza A Madison V Nomeir AA Wang Y Lees E Parry D Sgambellone N Seghezzi W Schultz L Shanahan F Wiswell D Xu X Zhou Q James RA Paradkar VM Park H Rokosz LR Stauffer TM Guzi TJ 《Bioorganic & medicinal chemistry letters》2007,17(22):6220-6223
Properly substituted pyrazolo[1,5-a]pyrimidines are potent and selective CDK2 inhibitors. Compound 15j is orally available and showed efficacy in a mouse A2780 xenograft model. 相似文献
999.
Therapeutic applications of mesenchymal stromal cells 总被引:6,自引:0,他引:6
Brooke G Cook M Blair C Han R Heazlewood C Jones B Kambouris M Kollar K McTaggart S Pelekanos R Rice A Rossetti T Atkinson K 《Seminars in cell & developmental biology》2007,18(6):846-858
Mesenchymal stromal cells (MSC) are multipotent cells that can be derived from many different organs and tissues. They have been demonstrated to play a role in tissue repair and regeneration in both preclinical and clinical studies. They also have remarkable immunosuppressive properties. We describe their application in settings that include the cardiovascular, central nervous, gastrointestinal, renal, orthopaedic and haematopoietic systems. Manufacturing of MSC for clinical trials is also discussed. Since tissue matching between MSC donor and recipient does not appear to be required, MSC may be the first cell type able to be used as an "off-the-shelf" therapeutic product. 相似文献
1000.
Parker JC Irwin N Lavery KS Green BD O'Harte FP Gault VA Flatt PR 《Biological chemistry》2007,388(2):221-226
Effects of chemical ablation of the GIP and GLP-1 receptors on metabolic aspects of obesity-diabetes were investigated using the stable receptor antagonists (Pro3)GIP and exendin(9-39)amide. Ob/ob mice received a daily i.p. injection of saline vehicle, (Pro3)GIP, exendin(9-39)amide or a combination of both peptides over a 14-day period. Non-fasting plasma glucose levels were significantly (p<0.05) lower in (Pro3)GIP-treated mice compared to control mice after just 9 days of treatment. (Pro3)GIP-treated mice also displayed significantly lower plasma glucose concentrations in response to feeding and intraperitoneal administration of either glucose or insulin (p<0.05 to p<0.001). The (Pro3)GIP-treated group also exhibited significantly (p<0.05) reduced pancreatic insulin content. Acute administration of exendin(9-39)amide immediately prior to re-feeding completely annulled the beneficial effects of sub-chronic (Pro3)GIP treatment, but non-fasting concentrations of active GLP-1 were unchanged. Combined sub-chronic administration of (Pro3GIP) with exendin(9-39)amide revealed no beneficial effects. Similarly, daily administration of exendin(9-39)amide alone had no significant effects on any of the metabolic parameters measured. These studies highlight an important role for GIP in obesity-related forms of diabetes, suggesting the possible involvement of GLP-1 in the beneficial actions of GIP receptor antagonism. 相似文献