Diagnosis of Myocardial Viability by Fluorodeoxyglucose Distribution at the Border Zone of a Low Uptake Region

Purpose: In cardiac 2-[F-18]fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET) examination, interpretation of myocardial viability in the low uptake region (LUR) has been difficult without additional perfusion imaging. We evaluated distribution patterns of FDG at the border zone of the LUR in the cardiac FDG-PET and established a novel parameter for diagnosing myocardial viability and for discriminating the LUR of normal variants. Materials and Methods: Cardiac FDG-PET was performed in patients with a myocardial ischemic event (n = 22) and in healthy volunteers (n = 22). Whether the myocardium was not a viable myocardium (not-VM) or an ischemic but viable myocardium (isch-VM) was defined by an echocardiogram under a low dose of dobutamine infusion as the gold standard. FDG images were displayed as gray scaled-bull’s eye mappings. FDG-plot profiles for LUR ( = true ischemic region in the patients or normal variant region in healthy subjects) were calculated. Maximal values of FDG change at the LUR border zone (a steepness index; Smax scale/pixel) were compared among not-VM, isch-VM, and normal myocardium. Results: Smax was significantly higher for n-VM compared to those with isch-VM or normal myocardium (ANOVA). A cut-off value of 0.30 in Smax demonstrated 100 % sensitivity and 83 % specificity for diagnosing n-VM and isch-VM. Smax less than 0.23 discriminated LUR in normal myocardium from the LUR in patients with both n-VM and isch-VM with a 94 % sensitivity and a 93 % specificity. Conclusion: Smax of the LUR in cardiac FDG-PET is a simple and useful parameter to diagnose n-VM and isch

A novel method, digital genome scanning detects KRAS gene amplification in gastric cancers: involvement of overexpressed wild-type KRAS in downstream signaling and cancer cell growth

<p>Abstract</p> <p>Background</p> <p>Gastric cancer is the third most common malignancy affecting the general population worldwide. Aberrant activation of KRAS is a key factor in the development of many types of tumor, however, oncogenic mutations of <it>KRAS </it>are infrequent in gastric cancer. We have developed a novel quantitative method of analysis of DNA copy number, termed digital genome scanning (DGS), which is based on the enumeration of short restriction fragments, and does not involve PCR or hybridization. In the current study, we used DGS to survey copy-number alterations in gastric cancer cells.</p> <p>Methods</p> <p>DGS of gastric cancer cell lines was performed using the sequences of 5000 to 15000 restriction fragments. We screened 20 gastric cancer cell lines and 86 primary gastric tumors for <it>KRAS </it>amplification by quantitative PCR, and investigated <it>KRAS </it>amplification at the DNA, mRNA and protein levels by mutational analysis, real-time PCR, immunoblot analysis, GTP-RAS pull-down assay and immunohistochemical analysis. The effect of <it>KRAS </it>knock-down on the activation of p44/42 MAP kinase and AKT and on cell growth were examined by immunoblot and colorimetric assay, respectively.</p> <p>Results</p> <p>DGS analysis of the HSC45 gastric cancer cell line revealed the amplification of a 500-kb region on chromosome 12p12.1, which contains the <it>KRAS </it>gene locus. Amplification of the <it>KRAS </it>locus was detected in 15% (3/20) of gastric cancer cell lines (8–18-fold amplification) and 4.7% (4/86) of primary gastric tumors (8–50-fold amplification). <it>KRAS </it>mutations were identified in two of the three cell lines in which <it>KRAS </it>was amplified, but were not detected in any of the primary tumors. Overexpression of KRAS protein correlated directly with increased <it>KRAS </it>copy number. The level of GTP-bound KRAS was elevated following serum stimulation in cells with amplified wild-type <it>KRAS</it>, but not in cells with amplified mutant <it>KRAS</it>. Knock-down of <it>KRAS </it>in gastric cancer cells that carried amplified wild-type <it>KRAS </it>resulted in the inhibition of cell growth and suppression of p44/42 MAP kinase and AKT activity.</p> <p>Conclusion</p> <p>Our study highlights the utility of DGS for identification of copy-number alterations. Using DGS, we identified <it>KRAS </it>as a gene that is amplified in human gastric cancer. We demonstrated that gene amplification likely forms the molecular basis of overactivation of KRAS in gastric cancer. Additional studies using a larger cohort of gastric cancer specimens are required to determine the diagnostic and therapeutic implications of <it>KRAS </it>amplification and overexpression.</p

An Arabidopsis E3 Ligase, SHOOT GRAVITROPISM9, Modulates the Interaction between Statoliths and F-Actin in Gravity Sensing[W][OA]

This work describes the mechanism of statolith sedimentation during Arabidopsis gravity sensing. SGR9, a RING-type E3 ligase, is localized to statoliths, which interact with F-actin. SGR9 modulates the interaction between statoliths and F-actin and promotes the detachment of statoliths from F-actin, allowing the statoliths to sediment in the direction of gravity

Isolation of new gravitropic mutants under hypergravity conditions

Forward genetics is a powerful approach used to link genotypes and phenotypes, and mutant screening/analysis has provided deep insights into many aspects of plant physiology. Gravitropism is a tropistic response in plants, in which hypocotyls and stems sense the direction of gravity and grow upwards. Previous studies of gravitropic mutants have suggested that shoot endodermal cells in Arabidopsis stems and hypocotyls are capable of sensing gravity (i.e., statocytes). In the present study, we report a new screening system using hypergravity conditions to isolate enhancers of gravitropism mutants, and we also describe a rapid and efficient genome mapping method, using Next-Generation Sequencing (NGS) and Single Nucleotide Polymorphism (SNP)-based markers. Using the endodermal-amyloplast less 1 (eal1) mutant, which exhibits defective development of endodermal cells and gravitropism, we found that hypergravity (10 g) restored the reduced gravity responsiveness in eal1 hypocotyls and could, therefore, be used to obtain mutants with further reduction in gravitropism in the eal1 background. Using the new screening system, we successfully isolated six ene (enhancer of eal1) mutants that exhibited little or no gravitropism under hypergravity conditions, and using NGS and map-based cloning with SNP markers, we narrowed down the potential causative genes, which revealed a new genetic network for shoot gravitropism in Arabidopsis

Anticandidal pimaradiene diterpene from Phlomis essential oils

In the present study, it was aimed to investigate the phytochemical profile and antimicrobial effects of Phlomis lunariifolia Sm., Phlomis amanica Vierh., Phlomis monocephala P.H. Davis, Phlomis sieheana Rech. fil, Phlomis armeniaca Willd. essential oils collected from Turkey. The Phlomis essential oils were obtained from the aerial parts by hydrodistillation and were subsequently analyzed both by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Chromatographic separations followed by structure identification of individual compounds of interest from Phlomis essential oils were conducted using 1D and 2D NMR, FT-IR, UV and HRMS techniques. In addition, antimicrobial studies using a microdilution assay and TLC bioautography were applied to the essential oils and the relevant components. The analysis of the essential oils led to the identification of 143 compounds, where an unknown volatile compound was detected as the major compound (22.8% and 12.7%) in the essential oils of P. amanica and P. monocephala, respectively. After chromatographic clean up, the isolation and characterization of this compound resulted in (-)-8(14),15-isopimaradien-11 alpha-ol. The sesquiterpene germacrene-D was identified as the major constituent of P. lunariifolia (7.7%), P. sieheana (16.6%) and P. armeniaca (23.4%) oils. 4-Methoxycarbonyl-7-methyl cyclopenta[c]pyrane - a fulvoiridoid - was obtained by acid hydrolysis from iridoid ipolamiide which was shown to be present in the oils of P. armeniaca (1.4%) and P. sieheana (0.2%). Furthermore, Phlomis essential oils were investigated for their antifungal properties using a TLC bioautographic assay where the diterpene was shown as the active principle against Candida albicans and Candida tropicalis when compared with standard antifungal agents. Minimum inhibitory concentrations against various human pathogenic bacteria (from 125 to > 1000 mu g/ml), C. albicans and C. tropicalis (62.5-1000 mu g/ml), were determined using a microdilution assay. The results obtained from this study suggest that essential oils and their individual compounds thereof may be potential resource and ingredients for pharmaceuticals or cosmetics with antimicrobial activity. To cite this article: B. Demirci et al., C R. Chimie 12 (2009). (C) 2008 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved

Revised structure of the liverwort sesquiterpenoid pinguisanin

Nuclear Overhauser effect (n.O.e.) difference spectroscopy has shown that the structure of the liverwort sesquiterpenoid pinguisanin is 2α,7α-epoxypinguisane (2). The 13C n.m.r. resonances have been assigned, mainly by two-dimensional (2D) direct δC/δH correlation

Effects of Vegetation Switch and Subsequent Change in Soil Invertebrate Composition on Soil Carbon Accumulation Patterns, Revealed by Radiocarbon Concentrations

From the 20th International Radiocarbon Conference held in Kona, Hawaii, USA, May 31-June 3, 2009.Vegetation types strongly affect soil organic carbon (SOC) accumulation in the terrestrial ecosystem through multiple factors such as litter quality and soil biodiversity. However, the roles of soil fauna in SOC accumulation remain unclear. The objectives of this study were to (1) examine how changes in litter types and soil animal communities affect SOC accumulation in continuously forested or vegetation-switched forest areas; and (2) discuss the role of soil animals in SOC accumulation in forest ecosystems. We focused on soils that have accumulated on top of a volcanic ash layer in the 268 yr since a volcanic eruption in 1739. The radiocarbon "bomb spike" in the late 1950s and early 1960s provides a unique isotopic signature of soil carbon age. We investigated the combined effects of litter quality and soil invertebrate function on soil 14C accumulation patterns. To determine the effects of vegetation types on SOC accumulation, we selected 4 types of cool temperate forests, 2 of which had undergone a vegetation switch in about 1960 (conifer to broadleaved forest, CB; broadleaved forest to conifer, BC), and 2 that had continuous forests (conifer forest, CC; broadleaved forest, BB). The ∆14C values at depth intervals in CC were consistent with the expected bomb-14C profile. In contrast, ∆14C patterns in BB, BC, and CB differed from that of CC. Compared to CC, ∆14C values of the other sites showed relatively high 14C concentrations even in deeper soil layers, which suggests the bomb-induced 14C has been transported to a greater depth by soil animals. Current broadleaved forests (BB and CB) had higher biomass of litter-feeding invertebrates than in current coniferous forests (CC and BC). These results suggest that carbon from leaf litter was vertically translocated to deeper soil layers by the abundant soil invertebrates in broad-leaved forests. Disagreement with the expected soil profile in BC suggests that past vegetation (broadleaved forest) has affected the present SOC accumulation pattern.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

AMS Radiocarbon Dating of Holocene Tephra Layers on Ulleung Island, South Korea

From the 20th International Radiocarbon Conference held in Kona, Hawaii, USA, May 31-June 3, 2009.Ulleung Island, a large stratovolcano, is located in the western part of the Japan Sea (East Sea), 130 km off the eastern coast of the Korean Peninsula. The Ulleung-Oki (U-Oki) is a widely distributed tephra in and around the Japan Sea, and has an age of 10.7 cal ka BP obtained from the Lake Suigetsu data set (central Japan). Of the 7 tephra layers (U-7 to -1) on the island, the pumiceous U-4, U-3, and U-2 tephra layers are petrochemically and petrographically similar to the U-Oki tephra. To determine the eruption ages of 3 tephra layers on Ulleung Island, we conducted radiocarbon dating for 5 soil and 2 charcoal samples. Although the soil samples have the C/N ratios from 5 to 10, the obtained 14C dates are still consistent with the tephra stratigraphy of the island. The calibrated 14C dates for the U-4, U-3, and U-2 tephras are 11 cal ka BP, 8.3 or 9 cal ka BP, and 5.6 cal ka BP, respectively, indicating that the explosive eruptions occurred in the island with a time interval of 2000 to 3000 yr during the period of the early to middle Holocene. Based on our chronology, the U-4 tephra is most likely correlated with the U-Oki tephra.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202