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91.
Nadine Kraemer Ethiraj Ravindran Sami Zaqout Gerda Neubert Detlev Schindler Olaf Ninnemann Ralph Gr?f Andrea EM Seiler Angela M Kaindl 《Cell cycle (Georgetown, Tex.)》2015,14(13):2044-2057
Biallelic mutations in the gene encoding centrosomal CDK5RAP2 lead to autosomal recessive primary microcephaly (MCPH), a disorder characterized by pronounced reduction in volume of otherwise architectonical normal brains and intellectual deficit. The current model for the microcephaly phenotype in MCPH invokes a premature shift from symmetric to asymmetric neural progenitor-cell divisions with a subsequent depletion of the progenitor pool. The isolated neural phenotype, despite the ubiquitous expression of CDK5RAP2, and reports of progressive microcephaly in individual MCPH cases prompted us to investigate neural and non-neural differentiation of Cdk5rap2-depleted and control murine embryonic stem cells (mESC). We demonstrate an accumulating proliferation defect of neurally differentiating Cdk5rap2-depleted mESC and cell death of proliferative and early postmitotic cells. A similar effect does not occur in non-neural differentiation into beating cardiomyocytes, which is in line with the lack of non-central nervous system features in MCPH patients. Our data suggest that MCPH is not only caused by premature differentiation of progenitors, but also by reduced propagation and survival of neural progenitors. 相似文献
92.
Characterization of compost produced from separated pig manure and a variety of bulking agents at low initial C/N ratios 总被引:1,自引:0,他引:1
Nolan T Troy SM Healy MG Kwapinski W Leahy JJ Lawlor PG 《Bioresource technology》2011,102(14):7131-7138
The aim of this study was to investigate the composting of separated pig manure solids with or without a variety of bulking agents at a low initial C/N ratio (12.5-23.3). Compost stability was investigated using an oxygen uptake rate (OUR) test and compost maturity was investigated using a germination index test. All treatments showed typical patterns of compost temperature. Temperatures above 60 °C were achieved by Day 2, followed by a thermophilic phase (50-60 °C), which lasted for 1 to 2 weeks followed by a cooling phase. The stability of one of treatments which did not contain any bulking agent - OUR of 25 mmol O2 kg−1 OM hour−1 - was negatively affected by its initial high water content (69%). The addition of a bulking agent and initial water content below 60% were necessary to compost the separated solid fraction of pig manure at a low initial C/N ratio. 相似文献
93.
Topczewski JJ Callahan MP Kodet JG Inbarasu JD Mente NR Beutler JA Wiemer DF 《Bioorganic & medicinal chemistry》2011,19(24):7570-7581
The schweinfurthins are an intriguing group of anti-proliferative agents that display low nanomolar activities against several cell types, including the human-derived glioblastoma cell line SF-295, but have little impact on other cell lines even at micromolar concentrations. This activity has inspired the synthesis of seven of the natural schweinfurthins, all with the correct absolute stereochemistry, and a variety of analogues designed to probe different facets of the pharmacophore. Reported herein is the synthesis of several new schweinfurthin analogues varied at the C-5 position along with data on their biological activity in the NCI 60 cell-line assay. 相似文献
94.
Suurmond J Dorjée AL Boon MR Knol EF Huizinga TW Toes RE Schuerwegh AJ 《Arthritis research & therapy》2011,13(5):R150
Introduction
Mast cells have been implicated to play a functional role in arthritis, especially in autoantibody-positive disease. Among the cytokines involved in rheumatoid arthritis (RA), IL-17 is an important inflammatory mediator. Recent data suggest that the synovial mast cell is a main producer of IL-17, although T cells have also been implicated as prominent IL-17 producers as well. We aimed to identify IL-17 expression by mast cells and T cells in synovium of arthritis patients. 相似文献95.
Investigation of Design Space for Freeze-Drying: Use of Modeling for Primary Drying Segment of a Freeze-Drying Cycle 总被引:1,自引:0,他引:1
Koganti VR Shalaev EY Berry MR Osterberg T Youssef M Hiebert DN Kanka FA Nolan M Barrett R Scalzo G Fitzpatrick G Fitzgibbon N Luthra S Zhang L 《AAPS PharmSciTech》2011,12(3):854-861
In this work, we explore the idea of using mathematical models to build design space for the primary drying portion of freeze-drying process. We start by defining design space for freeze-drying, followed by defining critical quality attributes and critical process parameters. Then using mathematical model, we build an insilico design space. Input parameters to the model (heat transfer coefficient and mass transfer resistance) were obtained from separate experimental runs. Two lyophilization runs are conducted to verify the model predictions. This confirmation of the model predictions with experimental results added to the confidence in the insilico design space. This simple step-by-step approach allowed us to minimize the number of experimental runs (preliminary runs to calculate heat transfer coefficient and mass transfer resistance plus two additional experimental runs to verify model predictions) required to define the design space. The established design space can then be used to understand the influence of critical process parameters on the critical quality attributes for all future cycles. 相似文献
96.
Spagou K Theodoridis G Wilson I Raikos N Greaves P Edwards R Nolan B Klapa MI 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2011,879(17-18):1467-1475
Metabolic profiling of biofluids, based on the quantitative analysis of the concentration profile of their free low molecular mass metabolites, has been playing increasing role employed as a means to gain understanding of the progression of metabolic disorders, including obesity. Chromatographic methods coupled with mass spectrometry have been established as a strategy for metabolic profiling. Among these, GC-MS, targeting mainly the primary metabolism intermediates, offers high sensitivity, good peak resolution and extensive databases. However, the derivatization step required for many involatile metabolites necessitates specific data validation, normalization and analysis protocols to ensure accurate and reproducible performance. In this study, the GC-MS metabolic profiles of plasma samples from mice maintained on 12- or 15-month long low (10 kcal%) or high (60 kcal%) fat diets were obtained. The profiles of the trimethylsilyl(TMS)-methoxime(MeOx) derivatives of the free polar metabolites were acquired through GC-(ion trap)MS, using [U-(13)C]-glucose as the internal standard. After the application of a recently developed data correction and normalization/filtering protocol for GC-MS metabolomic datasets, the profiles of 48 out of the 77 detected metabolites were used in multivariate statistical analysis. Data mining suggested a decrease in the activity of the energy metabolism with age. In addition, the metabolic profiles indicated the presence of subpopulations with different physiology within the high- and low-fat diet mice, which correlated well with the difference in body weight among the animals and current knowledge about hyperglycemic conditions. 相似文献
97.
Dynamic model of CHO cell metabolism 总被引:1,自引:0,他引:1
Fed-batch cultures are extensively used for the production of therapeutic proteins. However, process optimization is hampered by lack of quantitative models of mammalian cellular metabolism in these cultures. This paper presents a new kinetic model of CHO cell metabolism and a novel framework for simulating the dynamics of metabolic and biosynthetic pathways of these cells grown in fed-batch culture. The model defines a subset of the intracellular reactions with kinetic rate expressions based on extracellular metabolite concentrations and temperature- and redox-dependent regulatory variables. The simulation uses the rate expressions to calculate pseudo-steady state flux distributions and extracellular metabolite concentrations at discrete time points. Experimental data collected in this study for several different CHO cell fed-batch cultures are used to derive the rate expressions, fit the parameters, and validate the model. The simulations accurately predicted the effects of process variables, including temperature shift, seed density, specific productivity, and nutrient concentrations. 相似文献
98.
Pati A Gronow S Zeytun A Lapidus A Nolan M Hammon N Deshpande S Cheng JF Tapia R Han C Goodwin L Pitluck S Liolios K Pagani I Ivanova N Mavromatis K Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Detter JC Brambilla E Rohde M Göker M Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Lucas S 《Standards in genomic sciences》2011,4(1):45-53
Bacteroides helcogenes Benno et al. 1983 is of interest because of its isolated phylogenetic location and, although it has been found in pig feces and is known to be pathogenic for pigs, occurrence of this bacterium is rare and it does not cause significant damage in intensive animal husbandry. The genome of B. helcogenes P 36-108(T) is already the fifth completed and published type strain genome from the genus Bacteroides in the family Bacteroidaceae. The 3,998,906 bp long genome with its 3,353 protein-coding and 83 RNA genes consists of one circular chromosome and is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
99.
Chertkov O Sikorski J Nolan M Lapidus A Lucas S Del Rio TG Tice H Cheng JF Goodwin L Pitluck S Liolios K Ivanova N Mavromatis K Mikhailova N Ovchinnikova G Pati A Chen A Palaniappan K Djao OD Land M Hauser L Chang YJ Jeffries CD Brettin T Han C Detter JC Rohde M Göker M Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Klenk HP Kyrpides NC 《Standards in genomic sciences》2011,4(1):13-22
Thermomonospora curvata Henssen 1957 is the type species of the genus Thermomonospora. This genus is of interest because members of this clade are sources of new antibiotics, enzymes, and products with pharmacological activity. In addition, members of this genus participate in the active degradation of cellulose. This is the first complete genome sequence of a member of the family Thermomonosporaceae. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 5,639,016 bp long genome with its 4,985 protein-coding and 76 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
100.
Zeytun A Sikorski J Nolan M Lapidus A Lucas S Han J Tice H Cheng JF Tapia R Goodwin L Pitluck S Liolios K Ivanova N Mavromatis K Mikhailova N Ovchinnikova G Pati A Chen A Palaniappan K Ngatchou-Djao OD Land M Hauser L Jeffries CD Han C Detter JC Ubler S Rohde M Tindall BJ Göker M Wirth R Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Klenk HP Kyrpides NC 《Standards in genomic sciences》2011,4(2):131-143
Hydrogenobacter thermophilus Kawasumi et al. 1984 is the type species of the genus Hydrogenobacter. H. thermophilus was the first obligate autotrophic organism reported among aerobic hydrogen-oxidizing bacteria. Strain TK-6(T) is of interest because of the unusually efficient hydrogen-oxidizing ability of this strain, which results in a faster generation time compared to other autotrophs. It is also able to grow anaerobically using nitrate as an electron acceptor when molecular hydrogen is used as the energy source, and able to aerobically fix CO(2)via the reductive tricarboxylic acid cycle. This is the fifth completed genome sequence in the family Aquificaceae, and the second genome sequence determined from a strain derived from the original isolate. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 1,742,932 bp long genome with its 1,899 protein-coding and 49 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献