Characterization of reactive versus tumor-bearing lymph nodes with interstitial magnetic resonance lymphography in an animal model

RATIONALE AND OBJECTIVES: To determine if magnetic resonance lymphography performed with subcutaneously administered AMI-227, a nanoparticulate iron oxide contrast agent, can distinguish reactive from tumor-bearing lymph nodes. MATERIALS AND METHODS: Mature male Copenhagen rats were inoculated with cell suspensions of R3327-MAT-LyLu rat prostate carcinoma (n = 21) or Freund's complete adjuvant (n = 15) in the left footpad to generate ipsilateral popliteal lymph node metastases or lymphadenitis. At 12 to 14 days after inoculation, T1-and T2-weighted magnetic resonance images of bilateral popliteal areas were obtained before and 24 hours after subcutaneous administration of AMI-227. Contrast-to-noise ratios were calculated in precontrast and postcontrast images. Bilateral popliteal nodes were excised for pathologic assessment. RESULTS: AMI-227 resulted in decreased contrast-to-noise ratios in reactive (T1-W = -7.01 +/- 1.13, T2- W = -31.64 +/- 5.35) and normal (T1 - W = -13.56 +/- 1.97, T2 - W = -21.62 +/- 2.51) nodes. Contrast-to-noise ratios were unchanged (T1 - W = -0.22 +/- 1.71, T2 - W = -2.20 +/- 4.19) in tumor-containing nodes. These differences in contrast-to-noise ratio changes between tumor-bearing versus nontumor-bearing nodes were statistically significant (P < 0.05). Histologic analysis showed similar distribution of AMI-227 within normal and reactive nodes, but not in tumor-bearing nodes. CONCLUSIONS: Differences in AMI-227-uptake between tumor- and nontumor-bearing nodes detected with magnetic resonance imaging are helpful for distinguishing the two entities.     

Nutritional quality and safety of European perch (Perca fluviatilis) from three lakes of Central Italy

European perch (Perca fluviatilis) harvested from three lakes of Central Italy were studied in different seasonal periods of a year to evaluate their nutritional quality and some safety aspects related to the pollution of the aquatic environment. The lakes considered, located in the Latium region, differed with respect to their volcanic (Bolsena and Bracciano Lakes) or artificial (Salto Lake) origin. Fillets of fish caught in the three lakes were characterised by good protein (17–19%) and mineral contents and low lipid levels (0.6–1.2%) throughout the year. Total lipids were characterised by low cholesterol levels (41.9–74.7 mg/100 g) and high percentages of total n − 3 polyunsaturated fatty acids (27.7–33.8% of total fatty acids), in particular docosahexaenoic acid (14.2–25.3% of total fatty acids). The qualitative analysis of the stomach content of perch confirmed their predatory feeding behaviour. The chemical and nutritional profiles of perch from the three lakes were comparable except for rubidium and cesium levels, which were higher in the muscle tissues of perch from the volcanic lakes. These minerals may represent elements of traceability of the origin of fish. Low levels of organochlorine pesticides and polychlorinated biphenyls, well below the Italian and European action limits, were detected in the muscle tissue of perch from all three lakes.     

A Novel Cell-Based Model for a Rare Disease: The Tks4-KO Human Embryonic Stem Cell Line as a Frank-Ter Haar Syndrome Model System

Tyrosine kinase substrate with four SH3 domains (Tks4) scaffold protein plays roles in cell migration and podosome formation and regulates systemic mechanisms such as adult bone homeostasis and adipogenesis. Mutations in the Tks4 gene (SH3PXD2b) cause a rare developmental disorder called Frank-Ter Haar syndrome (FTHS), which leads to heart abnormalities, bone tissue defects, and reduced adiposity. We aimed to produce a human stem cell-based in vitro FTHS model system to study the effects of the loss of the Tks4 protein in different cell lineages and the accompanying effects on the cell signalome. To this end, we used CRISPR/Cas9 (clustered, regularly interspaced, short palindromic repeats (CRISPR)/CRISPR associated (Cas9)) to knock out the SH3PXD2b gene in the HUES9 human embryonic stem cell line (hESC), and we obtained stable homo- and heterozygous knock out clones for use in studying the potential regulatory roles of Tks4 protein in embryonic stem cell biology. Based on pluripotency marker measurements and spontaneous differentiation capacity assays, we concluded that the newly generated Tks4-KO HUES9 cells retained their embryonic stem cell characteristics. We propose that the Tks4-KO HUES9 cells could serve as a tool for further cell differentiation studies to investigate the involvement of Tks4 in the complex disorder FTHS. Moreover, we successfully differentiated all of the clones into mesenchymal stem cells (MSCs). The derived MSC cultures showed mesenchymal morphology and expressed MSC markers, although the expression levels of mesodermal and osteogenic marker genes were reduced, and several EMT (epithelial mesenchymal transition)-related features were altered in the Tks4-KO MSCs. Our results suggest that the loss of Tks4 leads to FTHS by altering cell lineage differentiation and cell maturation processes, rather than by regulating embryonic stem cell potential.     

Infants' differential social responses to attractive and unattractive faces.

Two studies were conducted to examine infants' social responses to attractive and unattractive faces. In Study 1, 60 12-month-olds interacted with a stranger who wore a professionally constructed attractive or unattractive mask. The infants showed more positive affective tone, less withdrawal, and more play involvement with the stranger in the attractive condition. In Study 2, 43 12-month-olds played with an attractive and an unattractive doll. The infants played significantly longer with the attractive doll. These results extend and amplify earlier findings showing that young infants exhibit visual preferences for attractive over unattractive faces. Both visual and behavioral preferences for attractiveness are evidently exhibited much earlier in life than was previously supposed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Concentrations and Profiles of Polycyclic Aromatic Hydrocarbons in Some Commercial Brands of Tea-, Coffee-, and Cocoa-Based Food Drinks in Nigeria

Concentrations and profiles of polycyclic aromatic hydrocarbons were determined in some popular commercial brands of tea-, coffee-, and cocoa-based food drinks in Nigeria by gas chromatograph-flame ionization after hexane/dichloromethane extraction and clean up. The concentrations of the ∑16 Polycyclic aromatic hydrocarbons in these products ranged from 5.2–913.1, 38.7–593.1, and 38.0–1406.4 μg kg^?1 for tea-, coffee-, and cocoa-based food drinks, respectively. The polycyclic aromatic hydrocarbon profiles indicate the dominance of three and four rings PAHs in these food items. The concentrations of the European Food Safety Authority (EFSA) eight carcinogenic polycyclic aromatic hydrocarbons ranged from nd–218.9, nd–102.9, and nd–1248.5 μg kg^?1 for tea-, coffee-, and cocoa-based food drinks, respectively.     

Effect of temperature,catalyst and charge gas on the mean chemical structures of the products from hydrogenation of Liddell coal

Liddell coal (New South Wales, Australia) has been hydrogenated at 400, 425 and 450 °C with excess tetralin as vehicle and nitrogen or hydrogen as charge gas for 4 h at reaction temperature. In some experiments a nickel-molybdenum catalyst was used. The structures of the liquid and solid products were investigated by nuclear magnetic resonance spectroscopy, gel permeation chromatography and combustion analysis. Increasing the hydrogenation temperature from 400 to 450 °C decreases the yield of liquid products but increases conversion. At higher temperatures the liquid products are smaller in molecular size and molecular weight and contain a greater proportion of aromatic carbon and hydrogen; the solid residues also contain a greater proportion of aromatic carbon. The changes in variation of yield and structure with temperature are independent of the presence of catalyst under nitrogen and the nature of the charge gas. However, as the reaction system is capable of absorbing more hydrogen than can be supplied by the tetralin, the products from reactions with hydrogen as charge gas contain more hydrogen, some in hydroaromatic groups. Catalyst has little, if any, role in dissolution of the coal when a nitrogen atmosphere is used. When nitrogen is used as charge gas, reactions of coal-derived liquids with the catalyst do not alter the hydrogen, carbon or molecular size distributions in the products. The results show that the changes in composition of the liquid and solid products with increase in hydrogenation temperature are due to pyrolytic reactions and not to increased hydrogenation of aromatic rings.     

Finite cladding effects in W-fibres: a new interpretation of leakage losses

According to both experiments and calculations, the HE11 mode in depressed inner-cladding single-mode fibres should not be described beyond cutoff with the leaky mode formalism but with a formalism of coupling between a core mode and discrete, lossy cladding modes.     

TRPM2 Oxidation Activates Two Distinct Potassium Channels in Melanoma Cells through Intracellular Calcium Increase

Tumor microenvironments are often characterized by an increase in oxidative stress levels. We studied the response to oxidative stimulation in human primary (IGR39) or metastatic (IGR37) cell lines obtained from the same patient, performing patch-clamp recordings, intracellular calcium ([Ca²⁺]_i) imaging, and RT-qPCR gene expression analysis. In IGR39 cells, chloramine-T (Chl-T) activated large K⁺ currents (KROS) that were partially sensitive to tetraethylammonium (TEA). A large fraction of KROS was inhibited by paxilline—a specific inhibitor of large-conductance Ca²⁺-activated BK channels. The TEA-insensitive component was inhibited by senicapoc—a specific inhibitor of the Ca²⁺-activated KCa3.1 channel. Both BK and KCa3.1 activation were mediated by an increase in [Ca²⁺]_i induced by Chl-T. Both KROS and [Ca²⁺]_i increase were inhibited by ACA and clotrimazole—two different inhibitors of the calcium-permeable TRPM2 channel. Surprisingly, IGR37 cells did not exhibit current increase upon the application of Chl-T. Expression analysis confirmed that the genes encoding BK, KCa3.1, and TRPM2 are much more expressed in IGR39 than in IGR37. The potassium currents and [Ca²⁺]_i increase observed in response to the oxidizing agent strongly suggest that these three molecular entities play a major role in the progression of melanoma. Pharmacological targeting of either of these ion channels could be a new strategy to reduce the metastatic potential of melanoma cells, and could complement classical radio- or chemotherapeutic treatments.