Metabolite profiling identifies a key role for glycine in rapid cancer cell proliferation

Metabolic reprogramming has been proposed to be a hallmark of cancer, yet a systematic characterization of the metabolic pathways active in transformed cells is currently lacking. Using mass spectrometry, we measured the consumption and release (CORE) profiles of 219 metabolites from media across the NCI-60 cancer cell lines, and integrated these data with a preexisting atlas of gene expression. This analysis identified glycine consumption and expression of the mitochondrial glycine biosynthetic pathway as strongly correlated with rates of proliferation across cancer cells. Antagonizing glycine uptake and its mitochondrial biosynthesis preferentially impaired rapidly proliferating cells. Moreover, higher expression of this pathway was associated with greater mortality in breast cancer patients. Increased reliance on glycine may represent a metabolic vulnerability for selectively targeting rapid cancer cell proliferation.     

Quantification by allometric equations of carbon sequestered by Tectona grandis in different agroforestry systems

Non destructive methods for quantification of carbon seques-tration in tropical trees are inadequately developed. We described a stan-dardized method for estimating carbon stock in teak (Tectona grandi...     

Inhibition of Chlorophyll Synthesis and Enzymes of Nitrogen Assimilation by Selenite in Excised Maize Leaf Sefments during Greening

Supply of 0.1 mM sodium selenite (Na₂SeO₃ to excised maize leaf segments during greening reduced total chorophylls and inhibited in vivo nitrate reductase activity (NRA). Inhibition of chlorophyll formation by selenite was affected by ammonium but remained unaltered by nitrate. Selenite also inhibited NADH-glutamate dehydrogenase (NADH-GDH) and NADH-glutamate synthase (NADH-GOGAT) activities. Inclusion of ammonium enhanced the inhibition of NADH-GDH activity by selenite but decreased the inhibition of NADH-GOGAT activity by selenite. The results suggest the involvement of the glutamine synthetase/glutamate synthase (GS/GOGAT) pathway of ammonia assimilation in selenite toxicity during chlorophyll formation in greening maize leaf segments.     

Do boating and basking mix? The effect of basking disturbances by motorboats on the body temperature and energy budget of the northern map turtle

相似文献   

Effect of fasting duration on clinical pathology results in Wistar rats

Background: Fasting is an important preanalytical factor that may affect the interpretation of hematology and clinical biochemistry data in toxicology or pharmacology studies. Limited information is available on how the results may be affected by different durations of fasting. Objective: The purpose of this study was to assess the influence of fasting duration on clinical pathology results in male and female rats and to determine an optimum fasting time for preclinical studies. Methods: Male and female Wistar rats (10 each per group) were fasted for 0, 4, 8, 16, 24, and 48 hours. Changes in body weight and in the results of routine CBC and clinical chemistry analysis were evaluated by 1‐way ANOVA. Results: Body weight was significantly decreased by 4 hours of fasting in all rats, and hemoglobin concentration was significantly increased at 16 hours in male rats. Serum glucose and triglyceride concentrations in both sexes and cholesterol and high‐density lipoprotein‐C concentrations in female rats were also significantly decreased beginning at 16 hours. The creatinine concentration was increased in females after 16 hours of fasting. Serum alkaline phosphatase and alanine aminotransferase activities were significantly decreased after 8 hours in males and 16 hours in females. Conclusions: Fasting‐induced changes in clinical pathology results were consistent with hemoconcentration and altered nutrition and metabolic function. Most changes occurred at 16 hours, with minimal subsequent changes. Hence, a 16‐hour fasting duration may be recommended for preclinical studies involving clinical pathology measurements.     

A keratoprosthesis prototype for the dog

Objective  To describe the technique for implantation of a novel keratoprosthesis (KP) prototype and evaluate its application for the treatment of corneal blindness in dogs.
Animals studied  Seven dogs, all of them being clinically blind before surgery as a result of severe corneal endothelial disease (5/7) or chronic superficial keratitis (2/7) that were unresponsive to prior therapy.
Procedures  A silicone KP was implanted unilaterally, just anterior to Descemet's membrane, after creating a stromal pocket by deep stromal lamellar dissection.
Results  Implantation of the KP was accomplished without complication in six of seven operated dogs. In the remaining case, an intra-operative complication (perforation of Descemet's membrane) was associated with extrusion of the KP 8 weeks postoperatively. All operated eyes regained limited vision after surgery. Three to six months after implantation purulent keratitis occurred in all five eyes with endothelial disease, necessitating surgical removal of the KP 6 months postoperatively in 5/7 eyes.
Conclusions  This KP prototype shows promise as a treatment for certain blinding corneal diseases. However, changes in the design of this KP, allowing improved stromal integration, will be necessary before its clinical application can be approved.     

Identification of sediment source and sink areas in a Himalayan watershed using GIS and remote sensing

Erosion is a natural geomorphic process occurring continually over the Earth's surface and it largely depends on topography, vegetation, soil and climatic variables, and therefore, exhibits pronounced spatial variability due to catchment heterogeneity and climatic variation. This problem can be circumvented by discretizing the catchment into approximately homogeneous sub‐areas using GIS. In this study, the remote sensing and GIS techniques (through Imagine®8.6 and ArcGIS®9.1 software) were used for derivation of spatial information, catchment discretization, data processing etc. for the Himalayan Chaukhutia watershed (India). Various thematic layers for different factors of USLE were generated and overlaid to compute spatially distributed gross soil erosion maps for the watershed using 18‐year rainfall data. The concept of transport limited accumulation was formulated and used in ArcGIS® for generating the transport capacity maps. Using these maps, the gross soil erosion was routed to the catchment outlet using hydrological drainage paths, for derivation of transport capacity limited sediment outflow maps. These maps depict the amount of sediment rate from a particular grid in spatial domain and the pixel value of the outlet grid indicates the sediment yield at the outlet of the watershed. Up on testing, the proposed method simulated the annual sediment yield with less than ±40% error. Copyright © 2009 John Wiley & Sons, Ltd.     

Genetic diversity analysis in date palm (Phoenix dactylifera L.): a comparative assessment using ISSR and RAPD marker assays

SUMMARY

A comparative study was conducted to evaluate genetic diversity in 45 genotypes of date palm (Phoenix dactylifera L.), including both male and female plants, employing RAPD and ISSR marker systems. The data were analysed to calculate the total number of bands, the number of polymorphic bands, the percentage polymorphism, the average number of bands per primer, the effective multiplex ratio (EMR), the polymorphic information content (PIC), the marker index (MI), and genetic similarity coefficients. The 37 RAPD and 53 ISSR primers used generated 363 and 608 scorable amplified products, respectively, of which 95.0% and 90.9% were polymorphic. The ISSR markers produced more information than the RAPD markers due to their higher EMR and MI values. Jaccard similarity values among male plants, female plants, and between all male and all female plants varied between 0.72 – 0.80. The results indicate the effectiveness of these two marker systems for demonstrating genetic relationships among date palm genotypes.