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71.
Fesenko SV Voigt G Spiridonov SI Sanzharova NI Gontarenko IA Belli M Sansone U 《Radiation and environmental biophysics》2000,39(4):291-300
The experience gained in the aftermath of serious radiation accidents shows that forests are an important source of external
and internal exposure of the affected population. This paper presents the results of an assessment of the major radiological
consequences for forests of Russia, most heavily contaminated after the Chernobyl nuclear power plant (ChNPP) accident. Illustrated
in the Novozybkovsky district of the Russian Federation, the significance of different forest exposure pathways is estimated
and the doses resulting from forest pathways are compared with the doses from agricultural products. It has been found that
the contribution of mushrooms and berries to the internal doses of the population, relative to the doses from agricultural
products, varied from 10–15% in 1987 to 40–45% in 1996. The results indicate large differences in internal exposure of members
of the ”critical groups” and ”normal population”, increasing with time after deposition. Data are presented that give information
on the contribution of forests to the collective doses of inhabitants of the area under consideration. It has been shown that
for 10 years after the accident (1987–1996), the contribution of forest products to the collective dose of the rural population
living in contaminated forests of the Novozybkovsky district, amounts to about 20% (213 person Sv) of the total collective
dose of internal and external exposures. However, a potential impact of these products including the dose from exported products
is much higher and might reach 659 person Sv. It has been found that in the long-term after the ChNPP accident, serious attention
should be given to forest countermeasures, and restoration strategies should be selected on the basis of a combined analysis
of the effectiveness of forest and agricultural countermeasures.
Received: 16 March 2000 / Accepted: 10 September 2000 相似文献
72.
BACKGROUND AND AIMS: Because distylous species have two hermaphroditic style-length floral morphs, they face two sex allocation problems: the equilibrium morph ratio and the optimal allocation to pollen and seed production in each floral morph. Gender specialization is expected among distylous species when floral morphs differ in reproductive output. However, spatio-temporal variability in female reproductive output between morphs needs to be investigated to fully understand patterns of sexual expression and gender specialization in distylous plants. Between-year variation in flower and fruit production of hummingbird-pollinated Palicourea padifolia (Rubiaceae) was examined, focusing on functional gender expression of long- and short-styled morphs and comparing their reproductive performance in five consecutive years (1998-2002). METHODS: Between-year variation in inflorescence, floral bud and fruit production was monitored and quantified. These traits were then used as parameters to determine functional gender differences between floral morphs through time. KEY RESULTS: Inflorescence production varied among years but no significant differences were found between floral morphs. Long-styled plants initiated more floral buds per inflorescence every year than short-styled plants, suggesting higher allocation to pollinator attraction and, potentially, an increase in male fitness through pollen donation. Although fruit production was similar between morphs, their functional gender shifted across years. CONCLUSIONS: The gender expression inconsistency across years is surprising because a number of floral characters and attributes that contribute to differently attracting and rewarding effective pollinators in P. padifolia suggest gender specialization. The evidence that morphs of distylous species might specialize in functional gender mostly comes from differences among populations in seed production and non-equilibrium morph ratios based on 1-year field population surveys. The results suggest that more sampling through time is needed to detect gender specialization among distylous species with a perennial habit. 相似文献
73.
Lindon JC Nicholson JK Holmes E Keun HC Craig A Pearce JT Bruce SJ Hardy N Sansone SA Antti H Jonsson P Daykin C Navarange M Beger RD Verheij ER Amberg A Baunsgaard D Cantor GH Lehman-McKeeman L Earll M Wold S Johansson E Haselden JN Kramer K Thomas C Lindberg J Schuppe-Koistinen I Wilson ID Reily MD Robertson DG Senn H Krotzky A Kochhar S Powell J van der Ouderaa F Plumb R Schaefer H Spraul M;Standard Metabolic Reporting Structures working group 《Nature biotechnology》2005,23(7):833-838
74.
75.
The purpose of this document is to provide readers with a resource of different ongoing standardization efforts within the 'omics' (genomic, proteomics, metabolomics) and related communities, with particular focus on toxicological and environmental applications. The review includes initiatives within the research community as well as in the regulatory arena. It addresses data management issues (format and reporting structures for the exchange of information) and database interoperability, highlighting key objectives, target audience and participants. A considerable amount of work still needs to be done and, ideally, collaboration should be optimized and duplication and incompatibility should be avoided where possible. The consequence of failing to deliver data standards is an escalation in the burden and cost of data management tasks. 相似文献
76.
Sansone G Fabbrocini A Ieropoli S Langellotti A Occidente M Matassino D 《Cryobiology》2002,44(3):229-239
A successful cryopreservation procedure for sperm must guarantee recovery of the morphological and functional characteristics of the cells following thawing so that preserved semen can to be used comparably with non-preserved semen. The aim of this work was to identify a species-specific freezing protocol for sea bass (Dicentrarchus labrax) spermatozoa by optimising all the stages in the cryopreservation procedure. In the first stage of the experiments, the cryoprotectants and the relative concentrations that had the least toxic effect on motility at room temperature were selected. The capacity of the selected cryoprotectant substances was then assessed in freezing tests as follows: dimethyl sulfoxide (Me(2)SO) 5% and 7%, ethylene glycol (EG) 7% and 10%, propylene glycol (PG) 7% and 10%. The cryoprotectant that gave the best results in this second stage of the experiments was EG 10%, and this was then used for the optimisation of the different stages in the freezing procedure: two different times of adaptation to the cryoprotectant were tested (15min and 6h), as well as the effects of adding an energy substrate (1.25mM sodium pyruvate) to assess its possible use as an energy source. Lastly, using the extender (diluent+Na-pyruvate+EG10%) and the adaptation procedure (6h at 0-2 degrees C) that had given the best results in the preceding stages of the experiments, four cooling rates were tested: 10, 12, 15, 24 degrees C/min. It was shown that the semen that was diluted immediately after collection in extender that contained the cryoprotectant (EG 10%), was equilibrated for 6h at 0-2 degrees C and then cooled at a rate of 15 degrees C/min, showed motility on thawing comparable to that of fresh semen (P=0.045). 相似文献
77.
The detection and the isolation of a zinc-protein from the secretion of the rat dorsolateral prostate is described. The purification procedure, based on gel filtration and cationic exchange chromatography, allowed to separate a minor protein (Mr approximately 66,000) from free zinc ions and other secretory components. Two zinc ions were estimated to be associated with one molecule of isolated protein. The zinc-protein was labelled with 125I and then incubated at 37 degrees C with spermatozoa from rat epididymal cauda. Time-dependent in vitro binding of the radioactive protein to sperm cells was demonstrated. This binding was not affected by the presence of proteins from the seminal vesicle during the incubation, while it was blocked in the presence of an excess of unlabelled zinc-protein. After binding, the labelled spermatozoa were treated with a buffer containing 0.5% sodium deoxycholate and 40 mM EDTA; only very small amounts of label were removed from the cells, thus suggesting that the zinc-proteins were kept on the plasma membrane by interactions which do not involve merely hydrophobic bonds. 相似文献
78.
Clementina Sansone Alessandra Braca Elena Ercolesi Giovanna Romano Anna Palumbo Raffaella Casotti Maria Francone Adrianna Ianora 《PloS one》2014,9(7)
Diatoms are an important class of unicellular algae that produce bioactive polyunsaturated aldehydes (PUAs) that induce abortions or malformations in the offspring of invertebrates exposed to them during gestation. Here we compare the effects of the PUAs 2-trans,4-trans-decadienal (DD), 2-trans,4-trans-octadienal (OD) and 2-trans,4-trans-heptadienal (HD) on the adenocarcinoma cell lines lung A549 and colon COLO 205, and the normal lung/brunch epithelial BEAS-2B cell line. Using the viability MTT/Trypan blue assays, we show that PUAs have a toxic effect on both A549 and COLO 205 tumor cells but not BEAS-2B normal cells. DD was the strongest of the three PUAs tested, at all time-intervals considered, but HD was as strong as DD after 48 h. OD was the least active of the three PUAs. The effect of the three PUAs was somewhat stronger for A549 cells. We therefore studied the death signaling pathway activated in A549 showing that cells treated with DD activated Tumor Necrosis Factor Receptor 1 (TNFR1) and Fas Associated Death Domain (FADD) leading to necroptosis via caspase-3 without activating the survival pathway Receptor-Interacting Protein (RIP). The TNFR1/FADD/caspase pathway was also observed with OD, but only after 48 h. This was the only PUA that activated RIP, consistent with the finding that OD causes less damage to the cell compared to DD and HD. In contrast, cells treated with HD activated the Fas/FADD/caspase pathway. This is the first report that PUAs activate an extrinsic apoptotic machinery in contrast to other anticancer drugs that promote an intrinsic death pathway, without affecting the viability of normal cells from the same tissue type. These findings have interesting implications also from the ecological viewpoint considering that HD is one of the most common PUAs produced by diatoms. 相似文献
79.
Research Question
Recent discoveries have challenged the traditional view that the thalamus is the primary source driving spike-and-wave discharges (SWDs). At odds, SWDs in genetic absence models have a cortical focal origin in the deep layers of the perioral region of the somatosensory cortex. The present study examines the effect of unilateral and bilateral surgical resection of the assumed focal cortical region on the occurrence of SWDs in anesthetized WAG/Rij rats, a well described and validated genetic absence model.Methods
Male WAG/Rij rats were used: 9 in the resected and 6 in the control group. EEG recordings were made before and after craniectomy, after unilateral and after bilateral removal of the focal region.Results
SWDs decreased after unilateral cortical resection, while SWDs were no longer noticed after bilateral resection. This was also the case when the resected areas were restricted to layers I-IV with layers V and VI intact.Conclusions
These results suggest that SWDs are completely abolished after bilateral removal of the focal region, most likely by interference with an intracortical columnar circuit. The evidence suggests that absence epilepsy is a network type of epilepsy since interference with only the local cortical network abolishes all seizures. 相似文献80.
Rodrigo?González-Barrios Ernesto?Soto-Reyes Ricardo?Quiroz-Baez Eunice?Fabián-Morales José?Díaz-Chávez Victor?del Castillo Julia?Mendoza Alejandro?López-Saavedra Clementina?Castro Luis?A?HerreraEmail author 《Cell division》2014,9(1):6