196,115 research outputs found
Olfactory Preferences of Sitophilus zeamais to Cereal- and Legume-Based Pasta
No full textWe compared the attractiveness of five commercially available Italian macaroni pastas of different shapes (penne, casarecce, and fusilli) made from cereals and/or legumes [100% Triticum durum; 100% Cicer arietinum; 100% Lens esculenta; 50% Triticum durum + 50% Cicer arietinum; 60% Triticum durum + 40% Lens esculenta] to adults of Sitophilus zeamais (L.). A multiple-choice walking bioassay showed that S. zeamais adults were more attracted to cereal than legume pastas. The modified Flit-Track M-2 trap devices baited with pasta made with 100% T. durum captured an average of 61.4% of the adults released into the olfactometric arena after 7 days. Of the insects tested, pasta made with 100% C. arietinum trapped 3.8%, pasta made with 100% L. esculenta trapped 2.7%, pasta made with 50% T. durum + 50% C. arietinum trapped 4.3%, and pasta made with 60% T. durum + 40% L. esculenta trapped 4.2%. When individually compared, 79.6% of S. zeamais adults chose the Triticum durum pasta. Orientation to 100% Cicer pasta or 100% Lens pasta was not observed. In the choice test, only 37% and 25% were attracted to Triticum and Cicer pastas or Triticum and Lens pasta, respectively. Our results confirm that the low attractiveness of legume pasta is mainly due to the lack of attractant stimuli rather than the emission of repellent compounds. From a practical perspective, it is also interesting to note how mixed pasta decreases the risk of S. zeamais infestation
Bioactivity of cereal-and legume-based macaroni pasta volatiles to adult sitophilus granarius (l.)
No full textThe attractiveness of ten commercially available Italian macaroni pastas made from different cereals [Triticum durum; Triticum durum (whole wheat); Triticum dicoccum; mixture of five cereals; Triticum turgidum; Triticum turanicum] or legumes (Cicer arietinum; Lens culinaris; Pisum sativum; Vicia faba) to Sitophilus granarius, was compared. S. granarius adults were more attracted to cereal pastas than legume pastas, but the differences in attractiveness were not always significant. Consistent with the results of behavioural bioassays, the mortality of adults over 20 days exposed to pasta samples was 100% with the legume pasta samples and only 8% with the T. turanicum pasta. GC-MS analysis of HS-SPME extracts from the different pasta samples highlighted marked qualitative and quantitative differences, with aliphatic aldehydes and aliphatic alcohols being the most abundant volatile components of cereal-and legume-pastas, respectively. In two-choice behavioural bioassays, insect attraction to a 1:1 combination of T. turanicum and C. arietinum pastas (80%) was even higher than that observed in T. turanicum pasta alone (64%) and in C. arietinum pasta alone (20%). This strongly suggested that the low attractiveness of legume pasta is mainly due to the lack of attractant stimuli rather than emission of repellent compounds
Addressing Immune Response Dysfunction in an Integrated Approach for Testing and Assessment for Non-Genotoxic Carcinogens in Humans: A Targeted Analysis
No full textMost known chemical carcinogens induce the direct activation of DNA damage, either directly or following metabolic activation. However, carcinogens do not always operate directly through genotoxic mechanisms but can do so via non-genotoxic carcinogenic (NGTxC) mechanisms. Immune dysfunction is one of these key events that NGTxCs have been shown to modify. The immune system is a first line of defence against transformed cells, with an innate immune response against cancer cells and mechanisms of immune evasion. Here, we review the key events of immune dysfunction. These include immunotoxicity, immune evasion, immune suppression and inflammatory-mediated immune responses, and the key players in the molecular disruption of immune anti-cancer molecular signalling pathways, particularly those mediated by cytokines and the Aryl hydrocarbon Receptor, in relation to the identification of NGTxC. The plasticity of cytokines towards functional flexibility in response to environmental stressors is also discussed from an evolutionary heritage perspective. This is combined with a critical assessment of the suitability for the regulatory application of currently available test method tools and is corroborated by the key biomarkers of, e.g., MAPK, mTOR, PD-L1, TIL and Tregs, CD8+, FoxP3+, WNT, IL-17, IL-11, IL-10, and TNF alpha, as identified from robust cancer biopsy studies. Finally, an understanding of how to address these endpoints for chemical hazard regulatory purposes, within an integrated approach to testing and assessment for NGTxC, is proposed
BIOMARKER END-POINTS IN OCCUPATIONAL EXPOSURE TO ANTINEOPLASTIC DRUGS
No full textP104-037
BIOMARKER END-POINTS IN OCCUPATIONAL EXPOSURE TO ANTINEOPLASTIC DRUGS
A. Colacci (1), S. Perdichizzi (1), P. Silingardi (1), M. C. Nucci (2), M. Vaccari (1), A. Barbieri (3), C. Bolognesi (4), M. G. Mascolo (1), F. S. Violante (3), S. Grilli (5), E. Morandi (1).
(1) Environmental Protection and Health Prevention Agency, Emilia-Romagna, Italy, Bologna, Italy
(2) Occupational Health Unit, Sant’Orsola-Malpighi Hospital, Bologna, Italy,
(3) Occupational Medicine Unit, University of Bologna, Sant’Orsola-Malpighi Hospital, Bologna, Italy,
(4) Environmental Carcinogenesis Unit National Institute for Cancer Research (IST) – Genoa, Italy,
(5) Dept. Experimental Pathology, Cancer Research Section, Bologna University Medical School,
Antineoplastic drugs (AD) have been in clinical use for five decades. A number of studies indicate that antineoplastic drugs may cause increased genotoxic effects in pharmacists and nurses exposed in the workplace. Studies of toxicities, however, are complicated by a number of factors including the general lack of sensitive and specific measures of biological absorption as well as the "mixture" of exposures to various ADs in combination with workplace and lifestyle exposures. The present study aims at identifying markers of early exposure to AD in occupational groups, that could be applied in the evaluation and monitoring of primary prevention measures.
For this purpose, the study recruited a sample of nurses exposed to AD and a control group including not exposed nurses working in the same health care facility. Several approaches were adopted to investigate the early response to the exposure, including the environmental monitoring of working surfaces, the concentration of drugs in urine, the identification of micronuclei in peripheral lymphocytes and in buccal mucosa cells as well as the assessment of the expression of heat shock proteins (HSP). Despite the usage of personal protective equipment, 19 out of the 50 exposed workers were found positive for at least one of the checked drugs. The micronuclei induction was not increased in the exposed workers in both tests on peripheral blood lymphocytes and on exfoliated buccal cells. No difference was observed in the expression of HSPs 27, 70, 90, 110, chosen as early markers of exposure, between the exposed and not exposed groups. However, HSP 27 is significantly higher in the subgroup that was exposed to more than one drug and the expression varied according to the number of used drugs. This result is suggestive of a possibile use of HSP 27 as an early biomarker of exposure to multiple ADs
Binding of hexachloroethane to biological macromolecules from rat and mouse organs
No full textHexachloroethane (HCE) binds to macromolecules of rat and mouse both in vivo and in vitro after metabolic activation. The covalent binding index (CBI) to liver DNA in vivo is comparable to that of compounds classified as weak-moderate initiators and is of approximately the same order of magnitude as those of other halocompounds such as 1, 2-dichloroethane. HCE is bioactivated in vitro by microsomal enzymatic systems from murine liver and kidney and, to a greater extent, by cytosolic fractions from all assayed organs. HCE is less reactive than 1, 1, 2, 2-tetrachloroethane, which is more toxic and oncogenic. The ability of hexachloroethane and five other chloroethanes to react covalently with mouse liver DNA both in vivo and in vitro parallels the relative oncogenic potency of these hepatocarcinogenic chemicals in mouse liver. © 1988 Taylor & Francis Group, LLC
THE BALB/c 3T3 CELL TRANSFORMATION ASSAY TO ASSESS THE CARCINOGENIC ACTIVITY OF CHEMICALS
No full textThe new EU regulation for chemicals, REACH, specifically requires the development of alternatives in order to reduce and eventually replace studies on vertebrates. At the moment the cell transformation assay performed on rodent cell lines (BALB/c 3T3 or C3H10T1/2) or primary cells from Syrian Hamster is regarded as the only possible in vitro alternative to animal testing for carcinogenesis studies. Cell transformation assays have been proposed as screening tests for the carcinogenic potential of compounds
that have no evidence of genotoxicity (OECD, 2007) and are listed among the REACH methods, as reported in EU regulation EC 440/2008. For the last 20 years we have been tested many chemicals and complex mixtures by using BALB/c 3T3 A 31 cells in different experimental protocols (Colacci et al, 1990; Mascolo et al, 2010). Recently, several scientists proposed to switch to the BALB/c 3T3 A 31-1-1 cell clone to develop a validated protocol to fulfill REACH requirements. The present study was performed in the aim to compare the results obtained with the two different clones. Cells were treated with PAHs (3-MCA 2.5 μg/ml, B(a)P 2.5 μg/ml) and aloethanes (1,2-DBE 50 μg/ml). The induction of cytotoxicity and the onset of chemically transformed foci were evaluated by two different experimental protocols: i) the originally recommended protocol (Kakunaga, 1973; IARC/NCI/EPA Working Group, 1985), where cells were seeded at 10.000 cells/60 mm dish and exposed to chemicals in the culture medium for 72 h; ii) an improved protocol aiming at reducing the toxicity of the chemical treatment, where the number of seeded cells was increased from 10.000 to 30.000 per dish and the cell treatment started two days later and lasted 48 h instead of 72 h (Matthews et al, 1993). In both treatment schedules, at the end of the exposure, the treatment medium was replaced with complete medium and the cultures were maintained
for 4–6 weeks to allow the expression of transformed foci.
The two clones differed for the response to chemicals, probably because of the different metabolizing capacity. The A31-1-1 cells showed a higher inherent transformation rate after PAH treatment, but they were insensitive to 1,2-DBE. As DBE is bioactivated to reactive forms able to bind DNA mainly through the conjugation with intracellular glutathione (Guengerich, 2003), these results suggested a reduced activity of phase-2 enzymes involved in gluthatione conjugation in A31-1-1 cells. Our results seem to suggest that in vitro cell transformation protocols performed under REACH regulation should take in account the different sensitivity of BALB/c 3T3 clones to different classes of chemicals
Valanghe in reti booleane a topologia scale-free
No full textL'articolo tratta della simulazione di eventi di knock-out tramite reti booleane con topologia scale-free, e del confronto dei risultati con dati reali (eventi in Saccaromicies Cerevisiae
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
Noisy random boolean networks and cell differentiation
No full textAutocatalytic networks are widespread in nature, but theyare difficult to create or to reproduce in laboratory. There are howeverseveral models of coupled reactions which describe a phase transition toan autocatalytic cycle when a certain level of heterogeneity in the compositionof the chemical soup is reached, so it is interesting to understandwhy these phenomena are not easily achieved in the laboratory. For thispurpose we introduce here a model, inspired by a previous one by Kau-man, tailored for the study of such properties. In particular, we take intoaccount the stochastic nature of the dynamics of interacting molecules,in the case of a well stirred tank reactor. We describe the model andwe analyse its behaviour under dierent circumstances. In particular,the onset of an autocatalytic set is studied as the feed is varied, and itsstability is analysed
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
- …
