bluuebunny/crossref_metadata_2025_split huggingface dataset:
Occurrence of the cyanobacterial toxin cylindrospermopsin in northeast Germany
Authors: Fastner Jutta , Rücker Jacqueline , Stüken Anke , Preußel Karina , Nixdorf Brigitte , Chorus Ingrid , Köhler Antje , Wiedner Claudia 
Published: February 2007

AbstractThe frequent occurrence of the cyanobacterial toxin cylindrospermopsin (CYN) in the (sub)tropics has been largely associated with cyanobacteria of the order Nostocales of tropical origin, in particular Cylindrospermopsis raciborskii. C. raciborskii is currently observed to spread northwards into temperate climatic zones. In addition, further cyanobacteria of the order Nostocales typically inhabiting water bodies in temperate regions are being identified as CYN‐producers. Therefore, data on the distribution of CYN in temperate regions are necessary for a first assessment of potential risks due to CYN in water used for drinking and recreation. A total of 127 lakes situated in the north‐eastern part of Germany were investigated in 2004 for the presence of the toxin CYN and the phytoplankton composition. The toxin could be detected in half of the lakes (n = 63) and in half of 165 samples (n = 88). Concentrations reached up to 73.2 μg CYN/g DW. CYN thus proved more widely distributed than previously demonstrated. The analyses of phytoplankton data suggest Aphanizomenon sp. and Anabaena sp. as important CYN producers in Germany, and confirm recent findings of Aphanizomenon flos‐aquae as CYN‐producing species frequently inhabiting water bodies in temperate climatic regions. The data shown here suggest that CYN may be an important cyanobacterial toxin in German water bodies and that further data are needed to assess this. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 26–32, 2007.
Toxicity of the quinalphos metabolite 2‐hydroxyquinoxaline: Growth inhibition, induction of oxidative stress, and genotoxicity in test organisms
Authors: Riediger Sonja , Behrends Andreas , Croll Björn , Vega‐Naredo Ignacio , Hänig Nils , Poeggeler Burkhard , Böker Jutta , Grube Sascha , Gipp Juliane , Coto‐Montes Ana , Haldar Chandana , Hardeland Rüdiger 
Published: February 2007

AbstractThe quinalphos metabolite 2‐hydroxyquinoxaline (HQO), previously shown to photocatalytically destroy antioxidant vitamins and biogenic amines in vitro, was tested for toxicity in several small aquatic organisms and for mutagenicity in Salmonella typhimurium. In the rotifer Philodina acuticornis, HQO caused the disappearance of large individuals and increased hydroperoxide concentration. The latter effect was not only observed in animals kept in a light/dark cycle, but also in constant darkness, indicating that HQO can assume a reactive state and/or form reactive intermediates under the influence of either light or redox‐active metabolites, in particular, free radicals. Cell proliferation was inhibited in the ciliate Paramecium bursaria. In the dinoflagellate Lingulodinium polyedrum, which allows early detection of cellular stress on the basis of bioluminescence measurements, strong rises in light emission became apparent on the 2nd day of exposure to HQO and continued until cells died between 12 and 18 days of treatment. Oxidative damage of protein by HQO was demonstrated by measuring protein carbonyl in L. polyedrumin vivo as well as in light‐exposed bovine serum albumin in vitro. In an Ames test of mutagenicity, HQO proved to be genotoxic in both light‐ and dark‐exposed bacteria. HQO appears as a source of secondary quinalphos toxicity, which deserves further attention. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 33–43, 2007.
Early pregnancy failure induced by dibutyltin dichloride in mice
Authors: Ema Makoto , Fujii Sakiko , Ikka Tsuguo , Matsumoto Mariko , Hirose Akihiko , Kamata Eiichi 
Published: February 2007

AbstractIn this study, we examined the adverse effects of dibutyltin on initiation and maintenance of pregnancy after maternal administration during early pregnancy in mice. Following successful mating, female ICR mice were given dibutyltin dichloride (DBTCl) at 0, 7.6, 15.2, or 30.4 mg/kg bw/day by gastric intubation on days 0–3 or days 4–7 of pregnancy. Female mice were sacrificed on day 18 of pregnancy, and the pregnancy outcome was determined. After administration of DBTCl on days 0–3, the rate of nonpregnant females and the incidence of preimplantation embryonic loss were significantly increased at 30.4 mg/kg bw/day. The incidences of postimplantation embryonic loss in females given DBTCl on days 0–3 at 15.2 mg/kg and higher and on days 4–7 at 7.6 mg/kg bw/day and higher were increased. No increase in the incidence of fetuses with external malformations was observed after the administration of DBTCl on days 0–3 or days 4–7. A decline in the serum progesterone levels was detected in mice given DBTCl at 30.4 mg/kg bw/day on days 0–3 or days 4–7 of pregnancy. The data show that DBTCl adversely affects the initiation and maintenance of pregnancy when administered during early pregnancy in mice and suggest that the decline in serum progesterone levels is responsible for pregnancy failure. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 44–52, 2007.
Alteration of monoamine concentrations in the brain of medaka, Oryzias latipes, exposed to tributyltin
Authors: Nakayama Kei , Oshima Yuji , Tachibana Tetsuya , Furuse Mitsuhiro , Honjo Tsuneo 
Published: February 2007

AbstractWe measured the concentrations of monoamines in the brain of Japanese medaka, Oryzias latipes, exposed to tributyltin (TBT). Fish were exposed to 0, 1, 5, 25, or 125 μg g−1 of TBT via the diet for 21 days. After the administration period, six males and six females in each treatment group were dissected and their brains were collected. The following monoamines were analyzed: dopamine (DA), norepinephrine (NE), epinephrine (E), and 5‐hydroxytryptamine (5‐HT). The metabolites of DA, 3,4‐dihydroxyphenylacetic acid and homovanilic acid, and the metabolite of 5‐HT, 5‐hydroxyindolacetic acid were also analyzed. The concentration of DA in the brain of male medaka and the concentrations of 5‐HT and NE in the female brains were significantly decreased by exposure to 125 μg TBT g−1. The concentrations of 5‐HT and NE in males and of DA in females were slightly decreased by 125 μg g−1 of TBT, although the differences were not statistically significant. The present study demonstrates that TBT alters monoamine concentrations in the brain of medaka. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 53–57, 2007.
Diesel exhaust particles disturb gene expression in mouse testis
Authors: Mori Tetsuya , Watanuki Taro , Kashiwagura Tadashi 
Published: February 2007

AbstractInhalation of diesel exhaust particles (DEP) has been found to reduce sperm production. There is a possibility that DEP exposure elicits changes in gene expression in testis. To identify the alteration of gene expression resulting from DEP exposure, we constructed subtracted cDNA libraries from mouse testis using the suppression subtractive hybridization method. We isolated 16 candidate clones whose expression levels changed after exposure. Some of these candidates were highly similar to known testis‐specific genes. Some of the clones also seemed to correlate with spermatogenesis. Northern blot analysis revealed that DEP exposure changed the expression levels of several clones in a dose‐dependent manner. For example, the expression of clone R8, which was very similar to human XRRA1, increased by 2.3‐fold in testis after DEP exposure. On the other hand, the expressions of long‐chain acyl‐CoA synthetase 6 (Acsl6) and serine/threonine kinase 35 reduced by 0.3‐fold. These results indicated that some constituents of DEP alter gene expression in the testis. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 58–63, 2007.
A rapid microbiotest for the detection of cyanobacterial toxins
Authors: Törökné Andrea , Vasdinnyei Rita , Asztalos B. Mária 
Published: February 2007

AbstractCyanobacteria occur widely in lakes, reservoirs, ponds, and slow flowing rivers. Many species are known to produce toxins (cyanotoxins), a number of which are of concern for health. Cyanotoxins vary in chemical structure and may be found intracellular or released into water. There is not only a wide variation in the toxicity of known cyanotoxins but a substantial number of toxins have to date not been identified chemically. Chemical analysis of cyanotoxins is nowadays not used for routine monitoring because it is time consuming, it requires specialized equipment and expertise, and is hence expensive. There is hence an urgent need for rapid tests in surface waters to detect cyanobacterial toxins because of the need for safe drinking water and safe natural bathing waters, which may be burdened by cyanobacterial blooms or scums. Previous investigations have already shown that larvae of the anostracan crustacean Thamnocephalus platyurus are quite sensitive to neurotoxic and hepatotoxic cyanotoxins. The present paper reports on the sensitivity comparison of the (1 h) Rapidtoxkit (based on a sublethal endpoint) and the (24 h) Thamnotoxkit microbiotest (based on mortality). Both assays make use of larvae of T. platyurus. The Rapidtoxkit is a new microbiotest that determines the decrease of ingestion of colored particles by the crustacean larvae, which are stressed by a short exposure to toxicants. Fifteen cyanobacterial samples composed of laboratory strains and natural bloom samples were tested by both microbiotests. All samples were also analyzed concurrently by HPLC for microcystins and cylindrospermopsin. The correlation coefficient between the two microbiotests (r = 0.82) showed the very good correspondence between the sublethal and the lethal effects. No known toxins could be detected in some samples, although the latter were found highly toxic to the test organisms in both bioassays. These results point to the presence of unknown toxin(s) produced by some cyanobacteria such as e.g., the Cylindrospermopsis raciborskii strain isolated from Lake Balaton in Hungary. This comparative study clearly showed that the 1 h Rapidtoxkit is an attractive rapid alternative to the Thamnotoxkit microbiotest. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 64–68, 2007.
Accumulation of nodularin in sediments, mussels, and fish from the Gulf of Gdańsk, southern Baltic Sea
Authors: Mazur‐Marzec Hanna , Tymińska Anna , Szafranek Janusz , Pliński Marcin 
Published: February 2007

AbstractIn the Gulf of Gdańsk, as in other parts of the Baltic Sea, toxic blooms of Nodularia spumigena are an annual phenomenon. In the present work, the accumulation of nodularin (NOD), a cyanobacterial pentapeptide hepatotoxin, in sediments, blue mussels, and flounders from the Gulf of Gdańsk was studied by enzyme‐linked immunosorbent assay (ELISA). In the surface layers of the sediments NOD concentration ranged from 2.3 ng/g dry weight (dw) several months after cyanobacterial bloom to 75 ng/g dw during the bloom. The highest toxin content in mussels was 139 ng/g dw. In two sampling stations situated in the coastal waters of the Gulf of Gdańsk the concentrations of NOD in sediments and mussels were significantly lower than those measured in the Gulf of Finland. In sediments and mussels collected in the Gulf of Gdańsk, the toxin was also detected in March when N. spumigena did not occur. In flounder, NOD accumulated in the liver (489 ng/g dw), guts (21 ng/g dw), and gonads (21 ng/g dw). Hybride quadrupole‐time‐of‐flight liquid chromatography/mass spectrometry/mass spectrometry (TOF‐LC/MS/MS) confirmed the presence of NOD in sediment, mussel, and fish samples. Additionally, other NOD analogues, ([DMAdda3]NOD and [dhb5]NOD), were detected in sediments and mussel tissue. No NOD conjugates with reduced glutathione or cysteine were found in fish and mussels. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 101–111, 2007.
1H NMR spectra of methylcitric acid in urine
Authors: Krawczyk H. , Gradowska W. 
Published: February 2007

SummaryMethylcitric acid (3‐carboxy‐3‐hydroxy‐2‐methyl‐pentanedioic acid; MCA) is elevated in body fluids of patients with propionic acidaemia (PA; McKusick: 232000, 232050), methylmalonic aciduria (MMA; McKusick: 251000, 251120) and multiple carboxylase deficiency (McKusick: 253260, 253270). MCA molecule has two stereogenic centers so that it can occur in the form of four stereoisomers. Only two stereoisomers of MCA, (2S, 3S) and (2R, 3S), were found in human urine. They have different spectra and can be easily distinguished. We performed measurements of 1H, 13C NMR and gs‐HMQC (gradient‐selected Heteronuclear Multiple Quantum Coherence) on the samples of unprocessed urine of 6 patients suffering from propionic acidaemia and methylmalonic aciduria and identified the protons of MCA diastereoisomers, 3‐hydroxypropionic acid and methylmalonic acid.Having used NMR spectroscopy to identify stereoisomers of MCA in urine, we can conclude that this technique gives the possibility of analysing MCA diastereoisomers in body fluids.
Interaction Between Al‐δ Layered Sodium Disilicate and Surfactant
Authors: Dong Jinxiang , Li Liping , Xu Hong , Li Jinping 
Published: February 2007

AbstractThis paper investigated the interaction of Al‐δ‐Na2Si2O5with surfactants (LAS, AOS, K12 and AEO‐9) under condition approximating the detergent spray drying process. Al‐δ‐Na2Si2O5and the interaction samples were characterized by XRD, TG, FT‐IR and Ca2+ion binding capacity. The experimental results showed that Al‐δ‐Na2Si2O5might remain as δ phase after interacting with LAS. Al‐δ‐Na2Si2O5had changed to a mixed phase of δ phase and kanemite after interacting with K12 (or AEO‐9, AOS). LAS provides protection for the Al‐δ‐Na2Si2O5structure and K12 also provides protection to Al‐δ‐Na2Si2O5though it changed to a mixed phase when/msur/msolidwas equal to 2:1:3. Themsur/mδwas equal to 0.5, interaction time was 60 min, temperature was 60 ± 2°C and the relative crystallinity of the above samples were 28 and 26% higher than that of blank (the sample without surfactant under the same experimental conditions), respectively. AEO‐9 provided no obvious protection for the Al‐δ‐Na2Si2O5structure. AOS had destructive effect to the crystal structure of Al‐δ‐Na2Si2O5with δ phase relative crystallinity 10% lower than that of the blank under the same experiment condition.
Enhancing Vitamin E in Oilseeds: Unraveling Tocopherol and Tocotrienol Biosynthesis
Authors: Hunter Sarah C. , Cahoon Edgar B. 
Published: February 2007

AbstractNaturally occurring vitamin E, comprised of four forms each of tocopherols and tocotrienols, are synthesized solely by photosynthetic organisms and function primarily as antioxidants. These different forms vary in their biological availability and in their physiological and chemical activities. Tocopherols and tocotrienols play important roles in the oxidative stability of vegetable oils and in the nutritional quality of crop plants for human and livestock diets. The isolation of genes for nearly all the steps in tocopherol and tocotrienol biosynthesis has facilitated efforts to alter metabolic flux through these pathways in plant cells. Herein we review the recent work done in the field, focusing on branch points and metabolic engineering to enhance and alter vitamin E content and composition in oilseed crops.
Tocopherol Content and Profile of Soybean: Genotypic Variability and Correlation Studies
Authors: Rani Anita , Kumar Vineet , Verma Sandeep K. , Shakya Arvind K. , Chauhan G. S. 
Published: February 2007

AbstractPlant seed oils, including soybean seed oil, represent the major source of naturally derived tocopherols, the antioxidant molecules that act as free radical quenchers preventing lipid peroxidation in biological systems and vegetable oil products. All four isomers of tocopherols, i.e. α, β, γ, δ tocopherols that exist in nature are found in soybean seeds. The biological activity and the contribution of these isomers in improving the oxidative stability of vegetable oil are in reverse order. Because of the nutritive value and the importance for oil stability, enhancement of tocopherol content, through breeding programs, in soybean seeds has become a new and an important objective. Genotypic variability, which is the basis of every breeding program, is scarcely reported for tocopherol content and profile in soybean seeds. In the present investigation, the tocopherol content and profile in seed samples of 66 genotypes of Indian soybean were determined. The ratios observed between the lowest and the highest values for α, β, γ, δ, total tocopherol content were 1:13.6, 1:10.4, 1:7.5, 1:9.1, 1:7.9, respectively. The mean contents for α, β, γ, δ and total tocopherols were 269, 40, 855, 241 and 1,405 μg/g of oil, respectively. Total tocopherol content was the highest in ‘Co Soya2’ followed by ‘Ankur’. Concentration of α‐tocopherol was the highest (27%) in ‘Ankur’ followed by ‘MACS124’ (26%) whereas gamma tocopherol concentration was the highest (69%) in ‘VLS1’ and ‘PK327’ followed by ‘MACS13’ (67%). In view of the fact that levels of unsaturated fatty acids, apart from tocopherols, also determine the oxidative stability of vegetable oils, the relationship of four isomers of tocopherols with each other as well as with different unsaturated fatty acids and oil content was also investigated in the present study. All the four isomers of tocopherols exhibited highly significant correlations with each other (p < 0.001) whereas γ‐tocopherol and total tocopherol content showed a significant relationship with linoleic acid (p < 0.05).
Characterization of the fetuin-binding fraction ofNeospora caninumtachyzoites and its potential involvement in host-parasite interactions
Authors: VONLAUFEN N. , NAGULESWARAN A. , GIANINAZZI C. , HEMPHILL A. 
Published: February 2007

SUMMARYTerminal sialic acid residues on surface-associated glycoconjugates mediate host cell interactions of many pathogens. Addition of sialic acid-rich fetuin enhanced, and the presence of the sialidiase inhibitor 2-deoxy-2,3-dehydro-N-acetylneuraminic acid reduced, the physical interaction ofNeospora caninumtachyzoites and bradyzoites with Vero cell monolayers. Thus,Neosporaextracts were subjected to fetuin-agarose affinity chromatography in order to isolate components potentially interacting with sialic acid residues. SDS-PAGE and silver staining of the fetuin binding fraction revealed the presence of a single protein band of ∼65 kDa, subsequently named NcFBP (Neospora caninumfetuin-binding protein), which was localized at the apical tip of the tachyzoites and was continuously released into the surrounding medium in a temperature-independent manner. NcFBP readily interacted with Vero cells and bound to chondroitin sulfate A and C, and anti-NcFBP antibodies interfered in tachyzoite adhesion to host cell monolayers. In additon, analysis of the fetuin binding fraction by gelatin substrate zymography was performed, and demonstrated the presence of two bands of 96 and 140 kDa exhibiting metalloprotease-activity. The metalloprotease activity readily degraded glycosylated proteins such as fetuin and bovine immunoglobulin G heavy chain, whereas non-glycosylated proteins such as bovine serum albumin and immunoglobulin G light chain were not affected. These findings suggest that the fetuin-binding fraction ofNeospora caninumtachyzoites contains components that could be potentially involved in host-parasite interactions.
Metazoan parasite species richness in Neotropical fishes: hotspots and the geography of biodiversity
Authors: LUQUE J. L. , POULIN R. 
Published: February 2007

SUMMARYAlthough research on parasite biodiversity has intensified recently, there are signs that parasites remain an underestimated component of total biodiversity in many regions of the planet. To identify geographical hotspots of parasite diversity, we performed qualitative and quantitative analyses of the parasite-host associations in fishes from Latin America and the Caribbean, a region that includes known hotspots of plant and animal biodiversity. The database included 10 904 metazoan parasite-host associations involving 1660 fish species. The number of host species with at least 1 parasite record was less than 10% of the total known fish species in the majority of countries. Associations involving adult endoparasites in actinopterygian fish hosts dominated the database. Across the whole region, no significant difference in parasite species richness was detected between marine and freshwater fishes. As a rule, host body size and study effort (number of studies per fish species) were good predictors of parasite species richness. Some interesting patterns emerged when we included only the regions with highest fish species biodiversity and study effort (Brasil, Mexico and the Caribbean Islands). Independently of differences in study effort or host body sizes, Mexico stands out as a hotspot of parasite diversity for freshwater fishes, as does Brasil for marine fishes. However, among 57 marine fish species common to all 3 regions, populations from the Caribbean consistently harboured more parasite species. These differences may reflect true biological patterns, or regional discrepancies in study effort and local priorities for fish parasitology research.
Local environmental factors characterizingIxodes ricinusnymph abundance in grazed permanent pastures for cattle
Authors: BOYARD C. , BARNOUIN J. , GASQUI P. , VOURC'H G. 
Published: February 2007

SUMMARYAlthoughIxodes ricinusticks are mainly associated with woodland, they are also present in open habitat such as pastures. The distribution of nymphalI. ricinuswas monitored by drag sampling the vegetation in May–June 2003 on 61 grazed permanent pastures for cattle located in central France. After selecting explanatory variables from among a set of 155, tick abundance was modelled on the perimeter of the pasture using a negative binomial model that took into account data overdispersion. An abundant tree layer at the perimeter of the pasture associated with a high humidity before sampling greatly enhanced the average number of capturedI. ricinusnymphs. The presence of apple or cherry trees around the pasture perimeter, the presence of trees or bushes at the pasture edge, woodland around the pasture and a high number ofI. ricinusnymphs in the nearest woodland to the pasture were also favourable to nymph abundance in the pasture. The study highlighted that woodland vegetation associated with humidity and the presence of attractive foraging areas for tick hosts around the pasture played a key role in the abundance ofI. ricinus. Finally, the results raised the question of whether and how transfer of ticks between woodland and grazed pastures occurs.
Image-based visual servoing schemes for nonholonomic mobile manipulators
Authors: De Luca Alessandro , Oriolo Giuseppe , Giordano Paolo Robuffo 
Published: February 2007

SUMMARYWe consider the task-oriented modeling of the differential kinematics of nonholonomic mobile manipulators (NMMs). A suitable NMM Jacobian is defined that relates the available input commands to the time derivative of the task variables, and can be used to formulate and solve kinematic control problems. When the NMM is redundant with respect to the given task, we provide an extension of two well-known redundancy resolution methods for fixed-base manipulators (Projected Gradient and Task Priority) and introduce a novel technique (Task Sequencing) aimed at improving performance, e.g., avoiding singularities. The proposed methods are applied then to the specific case of image-based visual servoing, where the NMM image Jacobian combines the interaction matrix and the kinematic model of the mobile manipulator. Comparative numerical results are presented for two case studies.