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Terms modified by Highest Concentration Selected AbstractsQuantitative variability of cyanogenesis in Cathariostachys madagascariensis,the main food plant of bamboo lemurs in Southeastern MadagascarAMERICAN JOURNAL OF PRIMATOLOGY, Issue 4 2009Daniel J. Ballhorn Abstract Giant bamboo (Cathariostachys madagascariensis) is a major food plant for three sympatric species of bamboo-eating lemurs (Hapalemur aureus, H. griseus, and Prolemur simus) in the rain forests of southeastern Madagascar. This plant species is strongly cyanogenic. However, quantitative data on cyanide concentration in C. madagascariensis are scarce. Previous studies reported 15,mg cyanide per 100,g fresh shoot material (corresponding to approx. 57,µmol cyanide per gram dry weight). However, we found mean concentrations (±SE) ranging from 139.3±19.32 in ground shoots to 217.7±16.80,µmol cyanide per gram dry weight in branch shoots. Thus, cyanogenesis of C. madagascariensis was up to four times higher than reported before. In contrast to the strongly cyanogenic shoots no cyanide could be detected in differently aged leaves of C. madagascariensis confirming earlier studies. Within individual shoots fine-scaled analysis revealed a characteristic ontogenetic pattern of cyanide accumulation. Highest concentrations were found in youngest parts near the apical meristem, whereas concentrations decreased in older shoot parts. Beyond the general intra-individual variability of cyanogenic features analyses indicated site-specific variability of both, the ontogenetic pattern of cyanide concentration as well as the total amount of cyanide accumulated in shoots. Additionally, analyses of soluble proteins,one important nutritive measure affecting food plant quality,demonstrated a converse quantitative relation of protein concentrations in leaves to cyanide concentration in shoots at the site-specific level. We, thus, suggest integrative analyses on quantitative variation of cyanogenesis together with nutritive plant parameters in future studies. This approach would allow obtaining more detailed insights into spatial variability of giant bamboo's overall browse quality and its impact on lemur herbivores. Am. J. Primatol. 71:305,315, 2009. © 2009 Wiley-Liss, Inc. [source] Sap properties and alk(en)ylresorcinol concentrations in Australian-grown mangoesANNALS OF APPLIED BIOLOGY, Issue 3 2009M.K. Hassan Abstract Physical and chemical properties of sap and sap concentrations of constitutive alk(en)ylresorcinols were determined in several varieties of mango grown in different locations in Queensland, Australia, over two consecutive cropping seasons. Sap weight from individual fruit, sap pH, percentage of non-aqueous sap and concentrations of constitutive alk(en)ylresorcinols (5- n -heptadecenylresorcinol and 5- n -pentadecylresorcinol) in sap varied significantly among the varieties. ,Calypso', ,Keitt', ,Kensington Pride' and ,Celebration' had the greatest proportion of non-aqueous sap, whereas ,Nam Doc Mai' had the least. The highest concentrations of 5- n -heptadecenylresorcinol were found in the sap of ,Kensington Pride', and the lowest in ,Honey Gold' and ,Nam Doc Mai'. Highest concentrations of 5- n -pentadecylresorcinol were found in sap of ,Calypso' and ,Celebration', and the lowest levels were in ,Honey Gold' and ,Nam Doc Mai'. There was a direct relationship between the percentage of non-aqueous sap and the concentrations of alk(en)ylresorcinols (r2 = 0.77 for 5- n -heptadecenylresorcinol, and r2 = 0.87 for 5- n -pentadecylresorcinol). The alk(en)ylresorcinols were distributed mainly in the upper non-aqueous phase of ,Kensington Pride' sap. Growing location also had significant effects on the composition of mango sap but the effects appeared to be related to differences in maturity. Sap removal is necessary to prevent sapburn, but considerable quantities of alk(en)ylresorcinols that assist in protecting the harvested fruit from anthracnose disease are also removed. [source] Ethnic variations in facial skin neurosensitivity assessed by capsaicin detection thresholdsCONTACT DERMATITIS, Issue 6 2009Roland Jourdain Background: Ethnic variations in sensitive skin have not been thoroughly explored and remain controversial. Objective: To objectively assess ethnic variations in facial skin neurosensitivity through individual detection thresholds of topically applied capsaicin. Patients/Methods: The single-blind, controlled study was performed in 144 women from three ethnicities: Asian, African, and Caucasian. Five solutions with increasing capsaicin concentration were successively applied to one side of nasolabial folds, while the other side simultaneously received the vehicle as control. The test was discontinued when the volunteer reported on the capsaicin side a sensation whatever its nature. Otherwise the experimenter continued the test, using the next solution with higher capsaicin content and so on, until the subject experienced a sensation on the capsaicin side. Results: Each ethnic group was divided into six sub-groups according to the level of sensitivity to capsaicin, i.e. from detection of the lowest concentration up to no detection of the highest concentration, 100-fold higher. Asian women tended to have higher capsaicin detection thresholds than Caucasians, but lower thresholds than Africans. Nevertheless, the distribution did not greatly differ between the three ethnicities. Conclusions: The capsaicin skin neurosensitivity test is painless and the changes across individuals of different ethnic backgrounds appear minimal. [source] Analysis of allergens in metalworking fluidsCONTACT DERMATITIS, Issue 5 2008Maj-Len Henriks-Eckerman Background:, Metalworking fluids (MWFs) are well-known causes of occupational contact dermatitis in machinists. Objective:, To gain information about skin sensitizers in MWFs and to compare it with the information in safety data sheets (SDSs). Methods:, A total of 17 samples of MWF concentrates were analysed for skin sensitizers known or suspected to be used in MWF. Alkanolamines, formaldehyde, isothiazolinones, methyldibromo glutaronitrile (MDBGN), and iodopropynyl butylcarbamate (IPBC) were separated by liquid chromatography. Resin acids of colophonium (colophony) were separated by gas chromatography. The substances were identified with mass spectrometric detection and ultraviolet detection. Results:, Of the MWFs, 15 contained 6,39% of alkanolamines, mostly monoethanolamine and triethanolamine. Formaldehyde was detected in all MWFs: the concentrations of total formaldehyde ranged between 0.002% and 1.3%. Benzisothiazolinone and octylisothiazolinone were detected in one fluid each. IPBC was detected in nine MWFs, and the highest concentration was 0.09%. Methylisothiazolinone and MDBGN were not detected in any of the fluids. Resin acids of colophonium were detected in seven MWFs in concentrations ranging from 0.41% to 3.8%. On the whole, the allergens analysed were poorly declared in the SDSs. Conclusions:, The content of total formaldehyde was not declared in any SDS. IPBC, a relatively new allergen, seems to be common in MWFs. Isothiazolinones may be relevant allergens of machinists, and they should be analysed in MWFs in case other sources are not identified. The occupational relevance of positive patch test results to MWF ingredients in machinists is difficult to determine if information in the SDSs is relied upon. [source] Atomistic simulation of the self-diffusion in Mg (001) surfaceCRYSTAL RESEARCH AND TECHNOLOGY, Issue 9 2008Jian-Min Zhang Abstract Both the formation energies and the intra- and inter-layer diffuse activation energies of a vacancy in the first six lattice planes of Mg (001) surface have been calculated by combining the modified analytical embedded-atom method (MAEAM) with molecular dynamics (MD). The results show that the effect of the surface on the formation and migration of the vacancy is only down to the third-layer. It is easer for a single vacancy to form and to migrate in the first layer. Furthermore, the vacancy in the second layer is favorable to migrate to the first layer. This is in agreement with the experimental results that the first layer has the highest concentration of the vacancy. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Susceptibility of Megalurothrips sjostedti developmental stages to Metarhizium anisopliae and the effects of infection on feeding, adult fecundity, egg fertility and longevityENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2000S. Ekesi Abstract The susceptibility of immature stages of the legume flower thrips, Megalurothrips sjostedti, to the entomopathogenic fungus Metarhizium anisopliae, was investigated under laboratory conditions. The adult stage was found to be more susceptible to infection than the larval and pupal stages. Mortality at all stages was dose-dependent, with the highest concentration of 1×108 conidia ml,1 producing the highest mortality (26, 46 and 100% for larvae, pupae and adults, respectively) at 8 days post-inoculation. At the same concentration, daily pollen consumption was significantly reduced at 2 days after treatment in infected adults but more slowly in infected larvae. Fecundity, egg fertility and longevity in adults surviving infection as larvae were significantly reduced compared to the control. [source] Horizontal transfer of an exopolymer complex from one bacterial species to anotherENVIRONMENTAL MICROBIOLOGY, Issue 4 2000D. Osterreicher-Ravid Alasan, the exocellular polymeric emulsifier produced by Acinetobacter radioresistens KA53 was shown to bind to the surface of Sphingomonas paucimobilis EPA505 and Acinetobacter calcoaceticus RAG-1. The presence of alasan on the surface of S. paucimobilis EPA505 and A. calcoaceticus RAG-1 caused a decrease in their cell-surface hydrophobicities. Binding was proportional to the concentration of recipient cells and input alasan. At the highest concentration of A. calcoaceticus RAG-1 (4 × 109 ml,1) and alasan (20 µg ml,1) tested, 75% of the alasan was cell bound. Alasan binding was measured by the loss of emulsifying activity and alasan protein and polysaccharide from the aqueous phase after incubation of alasan with the recipient cells. In addition, alasan was visualized on the surface of the recipient cells by staining with anti-alasan antibodies and rhodamine-labelled secondary antibodies. Moreover, when the alasan-producing A. radioresistens KA53 was grown together with A. calcoaceticus RAG-1, alasan was released from the producing strain and became bound to the recipient RAG-1 cells, as demonstrated by fluorescence microscopy. This horizontal transfer of exopolymers from one bacterial species to another has significant implications in natural microbial communities, coaggregation and biofilms. [source] Multimarker approach in transplanted mussels for evaluating water quality in Charentes, France, coast areas exposed to different anthropogenic conditionsENVIRONMENTAL TOXICOLOGY, Issue 5 2003M. Roméo Abstract An active biomonitoring experiment was performed using mussels collected at a clean site, Fier d'Ars, and transplanted to two locations, outside the harbor of La Rochelle and in the Baie de L'Aiguillon along the coast of Charentes (French Atlantic coast) beginning in April for several months. Mussels were collected in June and October. The cadmium, copper, and zinc concentrations of all resident and transplanted mussel samples and the polycyclic aromatic hydrocarbon and polychlorinated biphenyl concentrations in some mussel samples and in the sediment samples were determined. Mussel response was evaluated for several biochemical biomarkers: concentrations of metallothionein, activities of glutathione S-transferase and acetylcholinesterase (AChE) and levels of thiobarbituric reactive substance (TBARS). The physiological status of the animals was assessed using the condition index. A principal component analysis performed with the chemical and biochemical results of the evaluations of the resident and transplanted mussels collected in June allowed them to be separated into three groups: resident mussels from la Rochelle with high metal and TBARS levels, resident mussels from Baie de L'Aiguillon with a very high condition index, and resident mussels from Fier d'Ars and transplanted mussels at La Rochelle and Baie de L'Aiguillon with low TBARS and AChE activities. Strong seasonal variation from June to October of all parameters was noted. Mussels transplanted to La Rochelle appeared to be the most "polluted" in their pollutant concentrations and biochemical responses; moreover, the La Rochelle site had the highest concentration of organics in sediments of all the sites. The choice of Fier d'Ars as a reference site may be questionable because some of the biomarker responses of the mussels were higher than expected there, although these pollutants in mussels and sediment were present at the lowest concentrations measured. © 2003 Wiley Periodicals, Inc. Environ Toxicol 18: 295,305, 2003. [source] The influence of microcystin-LR and hepatotoxic cyanobacterial extract on the water plant Spirodela oligorrhizaENVIRONMENTAL TOXICOLOGY, Issue 5 2002Zdzis, awa Romanowska-Duda Abstract The eutrophication of the Sulejów Reservoir dam in Poland is related to toxicity from cyanobacterial blooms. The main species responsible for hepatotoxic bloom formation is Microcystis aeruginosa. The aim of this study was to evaluate the influence of toxic cyanobacterial extract on the growth and morphology of the water plant Spirodela oligorrhiza, compared with commercial-grade microcystin-LR (MC-LR). It was found that after 96 h of incubation the highest concentration of cyanobacterial extract, containing 0.344 mg MC-LR/L, reduced the number of fronds by about 50% in comparison with the control. The extract effected a reduction in the frond mass and a decrease in chlorophyll (a + b) concentration. A reduction in the number of fronds was also observed after the first 24 h of incubation in the presence of 0.2 and 0.1 ,g/L of commercial-grade MC-LR. Changes in activity of constitutive acid phosphatase and RNase after 7 days of incubation with commercial-grade MC-LR were observed. The results confirm the toxicity of cyanobacterial hepatotoxins to Spirodela oligorrhiza, which can be used as a sensitive bioindicator. © 2002 Wiley Periodicals, Inc. Environ Toxicol 17: 434,440, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/tox.10076 [source] Occurrence of pharmaceuticals and hormones in sewage sludgeENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2010Antonio Nieto Abstract The present study evaluates the presence of nine hormones and their conjugates and 20 pharmaceuticals such as anti-inflammatories, lipid regulators, and antibiotics among others in sewage sludge from two sewage treatment plants (STPs) in the Tarragona area (Spain) for the period March 2007 until March 2008. Target analytes have been determined using different methods involving pressurized liquid extraction and liquid chromatography (electrospray ionization) tandem mass spectrometry (MS-MS). Most of the pharmaceuticals and hormones were found at low micrograms per kilogram dry weight levels in the sewage sludge samples analyzed. Some compounds were present in all samples, such as acetaminophen, caffeine, carbamazepine, and ibuprofen, among others. Other compounds, such as estriol, were found only in the STP of Reus. The compounds that showed the highest concentration in both STPs were roxithromycin and tylosin (1,446 and 1,958,µg/kg dry wt, respectively). The presence of these compounds in sewage sludge demonstrated that they are partially or totally removed from the influent wastewater by sorption into the sewage sludge. Environ. Toxicol. Chem. 2010;29:1484,1489. © 2010 SETAC [source] Effect of in vitro and in vivo organotin exposures on the immune functions of murray cod (Maccullochella peelii peelii)ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2007Andrew J. Harford Abstract Murray cod (Maccullochella peelii peelii) is an iconic native Australian freshwater fish and an ideal species for ecotoxicological testing of environmental pollutants. The species is indigenous to the Murray-Darling basin, which is the largest river system in Australia but also the ultimate sink for many environmental pollutants. The organotins tributyltin (TBT) and dibutyltin (DBT) are common pollutants of both freshwater and marine environments and are also known for their immunotoxicity in both mammals and aquatic organisms. In this study, TBT and DBT were used as exemplar immunotoxins to assess the efficiency of immune function assays (i.e., mitogen-stimulated lymphoproliferation, phagocytosis in head kidney tissue, and serum lysozyme activity) and to compare the sensitivity of Murray cod to other fish species. The organotins were lethal to Murray cod at concentrations previously reported as sublethal in rainbow trout (i.e., intraperitoneal [i.p.] lethal dose to 75% of the Murray cod [LD75] = 2.5 mg/kg DBT and i.p. lethal dose to 100% of the Murray cod [LD100] = 12.5 mg/kg TBT and DBT). In vivo TBT exposure at 0.1 and 0.5 mg/kg stimulated the phagocytic function of Murray cod (F = 6.89, df = 18, p = 0.004), while the highest concentration of 2.5 mg/kg TBT decreased lymphocyte numbers (F = 7.92, df = 18, p = 0.02) and mitogenesis (F = 3.66, df = 18, p = 0.035). Dibutyltin was the more potent immunosuppressant in Murray cod, causing significant reductions in phagocytic activity (F = 5.34, df = 16, p = 0.013) and lymphocyte numbers (F = 10.63, df = 16, p = 0.001). [source] Neuropharmaceuticals in the environment: Mianserin-induced neuroendocrine disruption in zebrafish (Danio rerio) using cDNA microarraysENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2006Karlijn van der Ven Abstract Because of their environmental occurrence and high biological activity, human pharmaceuticals have received increasing attention from environmental and health agencies. A major bottleneck in their risk assessment is the lack of relevant and specific effect data. We developed an approach using gene expression analysis in quantifying adverse effects of neuroendocrine pharmaceuticals in the environment. We studied effects of mianserin on zebrafish (Danio rerio) gene expression using a brain-specific, custom microarray, with real-time polymerase chain reaction as confirmation. After exposure (0, 25, and 250 ,g/L) for 2, 4, and 14 d, RNA was extracted from brain tissue and used for microarray hybridization. In parallel, we investigated the impact of exposure on egg production, fertilization, and hatching. After 2 d of exposure, microarray analysis showed a clear effect of mianserin on important neuroendocrine-related genes (e.g., aromatase and estrogen receptor), indicating that antidepressants can modulate neuroendocrine processes. This initial neuroendocrine effect was followed by a "late gene expression effect" on neuronal plasticity, supporting the current concept regarding the mode of action for antidepressants in mammals. Clear adverse effects on egg viability were seen after 14 d of exposure at the highest concentration tested. Based on the specific molecular impact and the effects on reproduction, we conclude that further investigation of the adverse effects on the brain-liver-gonad axis is needed for a correct ecological risk assessment of antidepressants. [source] Bioluminescence inhibition assays for toxicity screening of wood extractives and biocides in paper mill process watersENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2004Anna Rigol Abstract The risk associated with wood extractives, biocides, and other additives in pulp and paper mill effluents was evaluated by performing a characterization of process waters and effluents in terms of toxicity and chemical analysis. The individual toxicity of 10 resin acids, two unsaturated fatty acids, and three biocides was estimated by measuring the bioluminescence inhibition with a ToxAlert® 100 system. Median effective concentration values (EC50) of 4.3 to 17.9, 1.2 to 1.5, and 0.022 to 0.50 mg/L were obtained, respectively. Mixtures of these three families of compounds showed antagonistic effects. Chemical analysis of process waters was performed by liquid chromatography-and gas chromatography-mass spectrometry. Biocides such as 2-(thiocyanome-thylthio)-benzotiazole (TCMTB) (EC50 = 0.022 mg/L) and 2,2-dibromo-3-nitrilpropionamide (DBNPA) (EC50 = 0.50 mg/L) were the most toxic compounds tested and were detected at concentrations of 16 and 59 ,g/L, respectively, in a closed-circuit recycling paper mill. Process waters from kraft pulp mills, printing paper mills, and packing board paper mills showed the highest concentration of resin acids (up to 400 ,g/L) and accounted for inhibition percentages up to 100%. Detergent degradation products such as nonylphenol (NP) and octylphenol (OP) and the plasticizer bisphenol A (BPA) were also detected in the waters at levels of 0.6 to 10.6, 0.3 to 1.4, and 0.7 to 187 ,g/L, respectively. However, once these waters were biologically treated, the concentration of detected organic compounds diminished and the toxicity decreased in most cases to values of inhibition lower than 20%. [source] Speciation of heavy metals in recent sediments of three coastal ecosystems in the Gulf of Cadiz, Southwest Iberian PeninsulaENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2003Veronica Sáenz Abstract A five-step sequential extraction technique was used to determine the partitioning of Cr, Mn, Fe, Cu, Zn, Cd, and Pb among the operative sedimentary phases (exchangeable ions, carbonates, manganese and iron oxides, sulfides and organic matter, and residual minerals) in coastal sediment from three locations in the southwest Iberian Peninsula. Two sites are located close to industrial areas, the salt marshes of the Odiel River and Bay of Cádiz, and one in a nonindustrial area, the Barbate River salt marshes. The Odiel River salt marshes also receive the drainage from mining activities in the Huelva region. In the sediments from the Bay of Cádiz and Barbate River salt marshes, Cr, Cu, Fe, and Zn were extracted from the residual fraction at percentages higher than 60%. In the sediments from the Odiel River salt marshes, concentrations of all the metals, except Cu, zn, and cd, exceeded 60% in the residual fraction as well. In the sediments from the Bay of Cádiz and Barbate River salt marshes, the main bioavailable metals were Mn and Cd; in those from the Odiel River salt marshes, the main bioavailable metals were Zn and Cd, respectively. The environmental risk was determined by employing the environmental risk factor (ERF), defined as ERF = (CSQV , Ci/CSQV), where Ci is the heavy metal concentration in the first four fractions and CSQV is concentration sediment quality value (the highest concentration with no associated biological effect). Our results showed that the sediments from the Cádiz Bay and Barbate River salt marshes do not constitute any environmental risk under the current natural conditions. In contrast, in the Odiel River salt marshes, Cu, Zn, and Pb yielded ERFs of less than zero at several sampling stations and, consequently, pose a potential threat for the organisms in the area. This is a consequence of the high levels of metals in the area derived from the mining activity (pyrite) and industrial activities and the association of these heavy metals with more labile fractions of the sediments. [source] Reproductive and transgenerational effects of methylmercury or Aroclor 1268 on Fundulus heteroclitusENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2001Mary Baker Matta Abstract This research determined the potential for methylmercury or Aroclor 1268 to disrupt reproduction and sexual differentiation in Fundulus heteroclitus. The research determined whether fish that are exposed to mercury or Aroclor 1268 survive and successfully reproduce; whether offspring of exposed fish hatch, survive, produce eggs, and fertilize them; and whether the secondgeneration offspring of exposed fish hatch and survive. Fundulus heteroclitus were exposed to mercury or Aroclor 1268 via contaminated food. Endpoints evaluated included survival, growth, fecundity, fertilization success, hatch success, larval survival, sex ratios, and the prevalence of gonadal abnormalities. In general, polychlorinated biphenyls were highly bioavailable and accumulated well through feeding. The only statistically significant effect observed as a result of treatment with Aroclor 1268 was an increase in growth in the offspring of exposed fish. Mercury was accumulated in a dose-dependent fashion via food exposures. Exposure to mercury in food increased mortality in male F. heteroclitus, which possibly occurred as a result of behavioral alterations. Increased mortality was observed at body burdens of 0.2 to 0.47 ,g/g. Offspring of F. heteroclitus fed mercury-contaminated food were less able to successfully reproduce, with reduced fertilization success observed at egg concentrations of 0.01 to 0.63 ,g/g, which corresponds with parent whole-body concentrations of 1.1 to 1.2 ,g/g. Offspring of exposed fish also had altered sex ratios, with treatment at moderate concentrations producing fewer females and treatment at the highest concentration producing more females than expected. Alterations in sex ratios were observed at concentrations of less than 0.01 ,g/g in eggs or between 0.44 and 1.1 ,g/g in parents. Offspring of mercury-exposed fish also had increased growth in moderate treatments, when egg concentrations were less than 0.02 ,g/g, or when parent whole bodies contained 0.2 to 0.47 ,g/g. In summary, exposure to mercury reduced male survival, reduced the ability of offspring to successfully reproduce, and altered sex ratios in offspring. Both direct effects on exposed fish and transgenerational effects were observed. [source] An idealised model of turbulent dispersion: two rectangular pulse initial conditionENVIRONMETRICS, Issue 5 2009Nils Mole Abstract An idealised model of turbulent dispersion was introduced by Zimmerman and Chatwin in 1995 and it was further developed by Mole and Yeun in 2007, for the case of an initial concentration field consisting of one rectangular pulse. Here we extend this model to the case of two initial pulses in order to investigate the effect of varying concentration. We present analytical and numerical results for the dependence of the variance, skewness, kurtosis and probability density function of concentration on time and on the pulse locations and concentrations. For moderately large concentration difference between the pulses, one pulse dominates and the behaviour is close to that for the one pulse case. This suggests that a model incorporating distributions of pulse separations and concentrations can be constructed by averaging over an ensemble of one pulse cases. The distributions used would be those appropriate to the ,strands' of highest concentration. Copyright © 2008 John Wiley & Sons, Ltd. [source] Glutamatergic neurons are present in the rat ventral tegmental areaEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2007Tsuyoshi Yamaguchi Abstract The ventral tegmental area (VTA) is thought to play an important role in reward function. Two populations of neurons, containing either dopamine (DA) or ,-amino butyric acid (GABA), have been extensively characterized in this area. However, recent electrophysiological studies are consistent with the notion that neurons that utilize neurotransmitters other than DA or GABA are likely to be present in the VTA. Given the pronounced phenotypic diversity of neurons in this region, we have proposed that additional cell types, such as those that express the neurotransmitter glutamate may also be present in this area. Thus, by using in situ hybridization histochemistry we investigated whether transcripts encoded by genes for the two vesicular glutamate transporters, VGluT1 or VGluT2, were expressed in the VTA. We found that VGluT2 mRNA but not VGluT1 mRNA is expressed in the VTA. Neurons expressing VGluT2 mRNA were differentially distributed throughout the rostro-caudal and medio-lateral aspects of the VTA, with the highest concentration detected in rostro-medial areas. Phenotypic characterization with double in situ hybridization of these neurons indicated that they rarely co,expressed mRNAs for tyrosine hydroxylase (TH, marker for DAergic neurons) or glutamic acid decarboxylase (GAD, marker for GABAergic neurons). Based on the results described here, we concluded that the VTA contains glutamatergic neurons that in their vast majority are clearly non-DAergic and non-GABAergic. [source] Macrophages in the embryo and beyond: Much more than just giant phagocytesGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 9 2008Dmitry A. Ovchinnikov Macrophages in a "MacBlue" mouse embryo at 12 days post coitus, visualized by the expression of enhanced cyan fluorescent protein (ECFP) from a bi-partite (Csf1r-Gal4/UAS-ECFP) transgene. Macrophages are interspersed throughout the embryo, with the highest concentration in the embryonic liver; they are also abundant around the developing heart, brain and eyes. See the review by Ovchinnikov in this issue. [source] Using in-field phosphate testing to rapidly identify middens at Piedras Negras, GuatemalaGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 8 2001J. Jacob Parnell Recent studies have promoted using soil phosphate analysis to detect ancient Maya sites by delimiting areas of occupation based on decomposed organic matter. Refuse associated with human activity increases organic matter around areas of ancient human habitation. Theoretically, the highest concentration of organic matter,detectable by phosphate analysis,should be directly associated with areas of refuse disposal. Thus, the objective of this study is to investigate the potential of phosphate analysis to detect residential middens in Piedras Negras, Guatemala. This paper presents the results of a sensitive, in-field phosphate analysis method applied as a midden prospection tool in residential areas. Phosphate concentration is correlated with artifact data obtained from a total of 37 test pits excavated in areas of varying phosphate concentration in three residential sites. A positive correlation between phosphate concentration and ceramic density indicates the potential of this method in defining and orienting excavations of residential areas. © 2001 John Wiley & Sons, Inc. [source] Polymorphisms in fatty acid-binding protein-3 (FABP3) , putative association with type 2 diabetes mellitus,,HUMAN MUTATION, Issue 2 2003Hyoung Doo Shin Abstract Fatty acid-binding proteins (FABPs) play key roles as transport vehicles of fatty compounds throughout the cytoplasm. Human FABP3, one of the FABPs, is present in a wide variety of tissues with highest concentration in cardiac and skeletal muscle. In an effort to identify polymorphic markers in potential candidate genes for type 2 diabetes, we have sequenced the full gene of FABP3, including the ,1,500bp promoter region. Fourteen polymorphisms were identified in FABP3: two ins/dels, two STRs, and ten SNPs (two in promoter, nine in intron, two in 3'UTR, and one in the 3' end). Among identified polymorphisms, five common sites including c.-530underscore;-532delCTC, c.-345T>C, c.348+429(CA)9-18, c.246+1806G>C, and c.634+483delT were genotyped in subjects with type 2 diabetes mellitus and normal control (n=669). By logistic and multiple regression analysis, one insertion/deletion polymorphism in the 3' end (c.634+483delT) of FABP3 appeared to be weakly associated with increased risk of type 2 diabetes (OR=1.78,1.94, P=0.03,0.04) and waist/hip ratio (WHR) (P=0.03). © 2003 Wiley-Liss, Inc. [source] Detection thresholds of capsaicin: a new test to assess facial skin neurosensitivityINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 6 2005R. Jourdain The goal of this study was to assess the accuracy/reliability of a new test designed to measure cutaneous neurosensitivity. The test was carried out on a random population of 150 healthy adult women and was based on the determination of individual detection thresholds of topically applied capsaicin. Five capsaicin concentrations were used in 10% ethanol aqueous solution (3.16 × 10,5%; 1 × 10,4%; 3.16 × 10,4%; 1 × 10,3%; 3.16 × 10,3%). The methodology used to attain the detection threshold was capsaicin application in increasing concentration on the nasolabial folds. The vehicle was simultaneously applied following a split-face, single-blind plan. The test was stopped as soon as the subject reported a specific sensation lasting more than 30 s on the capsaicin side. The safety of the test was judged as excellent by the panellists since all the reported sensations were considered as slightly or moderately perceptible. The test allowed the classification of the test population according to six threshold levels corresponding to the sensitive reaction to one of the five capsaicin concentrations and to the absence of sensitivity to the highest concentration. Surprisingly, the distribution of the population was not unimodal and seemed to reveal the existence of two different sub-groups: individuals with a low capsaicin detection threshold and those with a high threshold. These two sub-populations strongly differed in their respective self-perception of sensitive skin. The higher the self-declared sensitive skin incidence was, the lower the detection threshold was. This new test of skin neurosensitivity is easy, quick, and truly painless. It appears to be a promising tool for the cosmetic diagnosis of sensitive skin. [source] The characterization of the semi-solid W/O/W emulsions with low concentrations of the primary polymeric emulsifierINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 2 2005D. Vasiljevic Synopsis Semi-solid multiple W/O/W emulsions with low concentrations (0.8, 1.6 and 2.4% w/w) of lipophilic polymeric primary emulsifier PEG-30-dipolyhydroxystearate (PDHS) have been formulated. Both emulsions, primary and multiple, were prepared with high content of inner phase (,1 = ,2 = 0.8). All the formulations differ only in the lipophilic emulsifier concentration. Evaluating several parameters such as macroscopic and microscopic aspect, droplet size, accelerated stability under centrifugation and flow and oscillatory rheological behaviour, assessed the multiple systems. It is possible to formulate the semi-solid W/O/W multiple emulsions with low concentrations of PDHS as the primary emulsifier. It appeared that the highest long-term stable multiple emulsion with the lowest droplet size, the highest apparent viscosity and highest elastic characteristic, was the sample with the highest concentration (2.4% w/w) of the primary emulsifier. Résumé Les émulsions H/L/H semi-solides ont été formulées avec les concentrations basses (0.8, 1.6 et 2.4% m/m) de l'émulsifiant lipophile polymèrique PEG-30-dipolyhydroxystearate. Les émulsions simples et multiples ont été préparées avec la teneur élevée en phase intérieure (,1 = ,2 = 0.8). La teneur en émulsifiant lipophile était la seule différence entre ces formulations. L'aspect macroscopique et microscopique, la taille de globules, la stabilité physique déterminée par le test de centrifugation ainsi que le comportement rhéologique (rhéologie d'écoulement et oscillatoire) ont permis l'évaluation des émulsions multiples. Il est possible de formuler les émulsions H/L/H semi-solides multiples avec les concentrations basses de PEG-30-dipolyhydroxystearate comme émulsifiant primaire. Il a été découvert que l'émulsion H/L/H multiple avec le plus grand pourcentage (2.4% m/m) de l'émulsifiant primaire a le diamètre de globule le plus petit, la plus grande viscosité apparente et le plus grand module élastique ainsi que la plus longue stabilité. [source] A century of the synthesis of dapsone: its anti-infective capacity now and thenINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 10 2000Ronni Wolf MD Background Although dapsone was first synthesized in 1908, a quarter of a century was to pass before it was used in the treatment of bacterial infections. Dapsone was, however, too toxic for humans (because of the excess dosage which was administered at that time) and was thus considered to be of no value in the treatment of common bacterial infections. Since the early 1950s, dapsone has been recognized as being uniquely effective against a number of noninfectious, inflammatory diseases and, today, this is its main indication. Thus, the reason why dapsone was first introduced into medicine, namely the treatment of bacterial infections, has been set aside and its main current applications are the treatment of noninfectious, inflammatory, autoimmune, and bullous diseases. Objective To study the anti-infective capacity of dapsone against common bacterial infections. As many patients who receive dapsone for the treatment of noninfectious, inflammatory diseases have a concomitant bacterial infection or a superinfection of their skin disease, we thought that, if dapsone proved to be effective against common bacterial infections, it may obviate the need for an additional antimicrobial drug in these patients. Methods Three bacterial ATCC> strains (Streptococcus pyogenes, Staphylococcus aureus, and Escherichia coli) were tested by a macrodilution minimal inhibitory concentration (MIC) test for dapsone. Dapsone concentrations were between 0.06 and 1125 ,g/mL. Results Even the highest concentration of dapsone of 1125 ,g/mL did not inhibit bacterial growth. Conclusions Our results indicate that dapsone has no antibacterial effects whatsoever. Even at very high concentrations, it does not suppress the growth of most susceptible strains of bacteria. The story of dapsone (i.e. the long time that elapsed between its synthesis to its use for the chemotherapy of infectious diseases) will not repeat itself this time. [source] Evaluation of the extraction efficiency for polyphenol extracts from by-products of green kiwifruit juicingINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 12 2009Dongxiao Sun-Waterhouse Summary The health benefits of fruits are attributable in part to their bioactive components such as phenolics and pectic polysaccharides. By-products derived from kiwifruit processing can be a good source of such bioactive compounds. Extracts were produced using different concentrations of ethanol in water (0%, 30%, 50%, 74% and 96% v/v) from by-products (skin, residue and pulp) of the green-fleshed kiwifruit (Actinidia deliciosa,Hayward') juicing process. The amounts of phenolic compounds and uronic acid (UA) as well as the phenolic composition in each extract were determined. Results show that different by-products contained different concentrations of phenolics and pectic polysaccharides. Based on total phenolic contents, 96% v/v ethanol appeared to be the best extraction medium. The 30% or 74% ethanolic dilution was the second best medium for phenolic extraction from skin and pulp/residue, respectively. Water was a good medium for extracting satisfactory quantities of phenolics as well as the highest concentration of pectic polysaccharides. Phenolic profiling by high-performance liquid chromatography (HPLC) was used to detect individual phenolic compounds in an extract. Results using HPLC showed that alkali pre-treatment has improved the extraction efficiency of phenolics as a function of alkali concentration, fruit tissue type, extraction media, by-product preparation method, and class of polyphenols. As a result more efficient methods for both extraction and characterisation of polyphenols could be evaluated. [source] Cell proliferation and death in the brain of active and hibernating frogsJOURNAL OF ANATOMY, Issue 2 2009Silvia Cerri Abstract ,Binomial' cell proliferation and cell death have been studied in only a few non-mammalian vertebrates, such as fish. We thought it of interest to map cell proliferation/apoptosis in the brain of the frog (Rana esculenta L.) as this animal species undergoes, during the annual cycle, physiological events that could be associated with central nervous system damage. Therefore, we compared the active period and the deep underground hibernation of the frog. Using western blot analysis for proliferating cell nuclear antigen (PCNA), we revealed a positive 36 kDa band in all samples and found higher optical density values in the hibernating frogs than in active frogs. In both active and hibernating frogs, we found regional differences in PCNA-immunoreactive cells and terminal transferase dUTP nick-end labelling apoptotic cells in the ventricular zones and parenchyma areas of the main encephalon subdivisions. During the active period of the frogs, the highest concentration of PCNA-immunoreactive cells was found in the ventricle dorsal zone of the cerebral hemispheres but only some of the cells were apoptotic. By contrast, the tectal and cerebellar ventricular zones had a small or medium amount of PCNA-immunoreactive cells, respectively, and a higher number of apoptotic cells. During hibernation, an increased PCNA-immunoreactive cell number was observed in both the brain ventricles and parenchyma compared with active frogs. This increase was primarily evident in the lateral ventricles, a region known to be a proliferation ,hot spot'. Although differences existed among the brain areas, a general increase of apoptotic cell death was found in hibernating frogs, with the highest number of apoptotic cells being detected in the parenchyma of the cerebral hemispheres and optic tectum. In particular, the increased number of apoptotic cells in the hibernating frogs compared with active frogs in the parenchyma of these brain areas occurred when cell proliferation was higher in the corresponding ventricular zones. We suggest that the high number of dying cells found in the parenchymal regions of hibernating frogs might provide the stimulus for the ventricular zones to proliferate. Hibernating frogs could utilize an increased cell proliferation in the brain areas as a neuroprotective strategy to face cell death and the onset of neurological damages. Therefore, the hibernator promises to be a valuable model for studying the mechanisms naturally carried out by the central nervous system in order to adapt itself or survive adverse conditions. [source] Microinjected neutrophils retain the ability to take up bacteriaJOURNAL OF ANATOMY, Issue 5 2002M. M. Bird It is now possible to microinject protein to probe specific biochemical pathways and/or cell functions in small cells such as human neutrophils (Bird et al. J.Anat.198, 2001). We have shown that these cells retain their ability to modify their F-actin cytoskeleton following the microinjection procedure. The principal task of neutrophils is to hunt and kill bacteria by responding to chemotactic gradients which cause them to extend actin rich pseudopodia in the direction of the highest concentration of these molecules. On reaching their target the neutrophils make tight contact with the bacteria and phagocytosis ensues. Here we address the question of whether or not the microinjected cells are still able to maintain their normal phagocytic activities. Human neutrophils maintained in culture for 20 mins were confronted with Staphylococcus aureus (1 × 104 cells/mL) for 5 min and then injected with rat IgG as an exogenous protein that also serves as a marker for injected cells. After 30 min the cells were fixed for fluorescence or confocal microscopy in 3.7% formaldehyde and permeabilised for 5 min (0.2% Triton X-100 in PBS). They were then incubated for 45 min in 2.5 µL FITC-anti rat IgG and 1 µL TRITC-phalloidin (to show the F-actin cytoskeleton), in 996.5 µL of PBS, washed 6 times in PBS and mounted on slides in 5 µL Mowiol containing a grain of antiquench. For TEM cells were fixed in 1.5% glutaraldehyde in cacodylate buffer for 3 min at room temperature and then washed in 0.2 m cacodylate buffer 6 times before incubation with 1 mm NiCl2 and SIGMA fast DAB peroxidase tablets for 30 min. The cells were postfixed in a 2% solution of osmium tetroxide for 30 min, dehydrated through a series of graded ethanols, and embedded and sectioned for TEM. By TEM the injected neutrophils were observed to have taken up bacteria into vacuoles of varying size. At the earliest stages of this process, prior to and immediately following the initial release of granular contents and the initiation of mechanisms to rapidly destroy bacteria, the bacteria fitted more tightly in the vacuoles than at later stages. Injected neutrophils commonly contained several bacteria; more than one bacterium was frequently located within a single vacuole of substantial size. Confocal laser microscopic observations confirmed that cells containing ingested bacteria also contained IgG. Thus injected cells not only survive the microinjection procedure but also retain their ability to take up bacteria and initiate the digestive process. [source] In vivo metabolic effects of naringenin in the ethanol consuming rat and the effect of naringenin on adipocytes in vitroJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 3-4 2007K. Szkudelska Summary Naringenin is a bioactive flavanone involved in the inhibition of drug metabolism which exhibits antioxidant, anti-inflammatory and anticancerogenic properties and which recently appeared to be a factor mitigating the hyperlipidaemic effects in rats and rabbits. In the performed experiment, the effect of naringenin, administered intragastrically (50 mg/kg) for 2 weeks to normal and ethanol drinking rats, on insulin and leptin levels and on some metabolic parameters was investigated. Naringenin did not change the hormone levels in any group of rats. Blood glucose, triglyceride, total, esterified and free cholesterol and high-density lipoprotein-cholesterol concentrations were also unaffected by this compound. Only free fatty acids were elevated after the naringenin treatment in the water-drinking rats. In spite of unchanged glucose and insulin concentrations in blood, the tested flavanone reduced the glucose/insulin ratio in ethanol-receiving rats. Liver triglycerides, elevated due to ethanol ingestion, were partially normalized by naringenin. Other tested parameters like liver glycogen and cholesterol, muscle triglycerides and glycogen were not altered in any group of rats. The influence of naringenin (62.5, 125, 250 and 500 ,m) on basal and insulin-stimulated glucose conversion to lipids (lipogenesis) as well as on basal and epinephrine-stimulated glycerol release (lipolysis) in the isolated rat adipocytes was also tested. The basal and the stimulated lipogenesis tended to be decreased in the presence of the flavanone (250 ,m). This inhibitory effect intensified and was statistically significant at the highest concentration of naringenin. The tested compound did not evoke any effect on basal lipolysis while the epinephrine-stimulated process was limited at the highest concentration of the flavanone. Naringenin (62.5, 125, 250 and 500 ,m) had no effect on leptin secretion from the isolated rat adipocytes. Results obtained in our studies demonstrate that naringenin exerts a very weak influence on carbohydrate and lipid metabolism of normal and ethanol-consuming rats and on metabolism of isolated rat adipocytes. [source] Secretion of cortisol and aldosterone as a vulnerable target for adrenal endocrine disruption , screening of 30 selected chemicals in the human H295R cell modelJOURNAL OF APPLIED TOXICOLOGY, Issue 8 2008Erik Ullerås Abstract The adrenal gland is a vulnerable target for toxic insult. Disruption of adrenal steroidogenesis and hormone secretion may cause serious effects on human health. A human in vitro model is needed to predict effects, and elucidate mechanisms of endocrine disruption and adrenal toxicity. The human adrenocortical cell line H295R has been used to screen for effects on sex hormones. Here, we have analyzed the effect of 30 potential endocrine disrupting chemicals on the secretion of cortisol and aldosterone from the H295R cells, using specific ELISA assays. The effect of chemicals was analyzed for basal and forskolin- or angiotensin II-stimulated hormone secretion. The chemicals were tested at the highest concentration where they displayed no evident unspecific cytotoxicity. Quantitative and qualitative differences in effects on hormone secretion were demonstrated for the various chemicals. A subset of the chemicals displayed different effects on cortisol and aldosterone secretion, and in some cases the effects were different between basal and stimulated hormone secretion. Aminoglutethimide, prochloraz, ketoconazole, 6-hydroxyflavone, imazalil and etomidate had the most marked inhibitory effects on cortisol (with or without forskolin) and ketoconazole, 6-hydroxyflavone, imazalil and etomidate had the most marked effects on aldosterone (with or without angiotensin II). The results are discussed in terms of known effects, structural similarity and possible mechanisms. We have shown that adrenal steroidogenesis is a vulnerable target for toxic insult and that the H295R assay is a useful in vitro model for screening purposes. Copyright © 2008 John Wiley & Sons, Ltd. [source] Naringin, a grapefruit flavanone, protects V79 cells against the bleomycin-induced genotoxicity and decline in survivalJOURNAL OF APPLIED TOXICOLOGY, Issue 2 2007Abhinav Jagetia Abstract The effect of naringin, a grapefruit flavonone was studied on bleomycin-induced genomic damage and alteration in the survival of cultured V79 cells. Exposure of V79 cells to bleomycin induced a concentration dependent elevation in the frequency of binucleate cells bearing micronuclei (MNBNC) and a maximum number of MNBNCs were observed in the cells treated with 50 ,g ml,1 bleomycin, the highest concentration evaluated. This genotoxic effect of bleomycin was reflected in the cell survival, where a concentration dependent decline was observed in the cells treated with different concentrations of bleomycin. Treatment of cells with 1 mm naringin before exposure to different concentrations of bleomycin arrested the bleomycin-induced decline in the cell survival accompanied by a significant reduction in the frequency of micronuclei when compared with bleomycin treatment alone. The cell survival and micronuclei induction were found to be inversely correlated. The repair kinetics of DNA damage induced by bleomycin was evaluated by exposing the cells to 10 ,g ml,1 bleomycin using single cell gel electrophoresis. Treatment of V79 cells with bleomycin resulted in a continuous increase in DNA damage up to 6 h post-bleomycin treatment as evident by migration of more DNA into the tails (% tail DNA) of the comets and a subsequent increase in olive tail moment (OTM), an index of DNA damage. Treatment of V79 cells with 1 mm naringin reduced bleomycin-induced DNA damage and accelerated DNA repair as indicated by a reduction in % tail DNA and OTM with increasing assessment time. A maximum reduction in the DNA damage was observed at 6 h post-bleomycin treatment, where it was 5 times lower than bleomycin alone. Our study, which was conducted on the basis of antioxidant, free radical scavenging and metal chelating properties of naringin demonstrates that naringin reduced the genotoxic effects of bleomycin and consequently increased the cell survival and therefore may act as a chemoprotective agent in clinical situations. Copyright © 2006 John Wiley & Sons, Ltd. [source] Effect of selected alcohol dehydrogenase inhibitors on human hepatic lactate dehydrogenase activity , an in vitro studyJOURNAL OF APPLIED TOXICOLOGY, Issue 6 2005Jaroslaw Dudka Abstract Metabolic acidosis severely complicates methanol and ethylene glycol intoxications. Acidosis is caused by acid metabolites and can be intensified by lactate elevation. Lactate concentration depends on the NADH2/NAD ratio. Lactate dehydrogenase (LDH, E.C.1.1.1.27.) supplies more lactate when the level of NADH2 is elevated. The aim of the study was to evaluate the effect of alcohol dehydrogenase (ADH) inhibitors and substrates: cimetidine, EDTA, 4-methylpyrazole (4-MP), Ukrain and ethanol on LDH activity. The activity of LDH was determined spectrophotometrically in human liver homogenates incubated with cimetidine, EDTA, 4-MP and Ukrain at concentrations of 2 × 10,6, 10,5 and 5 × 10,5m as well as ethanol at concentrations of 12.50, 25.00, 50.00 mm. The LDH activity was significantly increased by 10,5 and 5 × 10,5m concentrations of cimetidine and 4-MP, and by all concentrations of ethanol. The most effective change of LDH activity of about 26% (P < 0.01) was observed at the highest concentration of ethanol. Ukrain inhibited LDH activity at both concentrations, i.e. 10,5 and 5 × 10,5m (P < 0.05). However, EDTA did not significantly influence LDH activity. The data showed that ethanol and 4-MP, the main antidotes in methanol or ethylene glycol poisoning, may increase liver LDH activity , an undesirable effect during the therapy of patients intoxicated with these alcohols. On the other hand, the decrease of LDH activity in the presence of Ukrain is a promising finding but definitely requires further investigation. Copyright © 2005 John Wiley & Sons, Ltd. [source] | ||||||||||||||||||||||||||||||||||||||||