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81.
Purpose

The effects of long-standing industrialization processes and poor environmental management practices have often left a harmful legacy for marine-coastal sites worldwide, causing a wide range of unforeseen impacts on the ecosystem and on human health. A critical revision of available data from three highly contaminated Italian sites (Augusta Bay, Sicily; Cagliari Gulf, Sardinia; Pozzuoli Bay, Campania) revealed the crucial role of biogeochemical/physical dynamics and potential widespread delivery of contaminants as key components for a wider comprehensive sediment management.

Materials and methods

Datasets of organic pollutants (ΣPAHs, ΣPCBs), heavy metals (As, Cd, Co, Cr, Cu, Hg, Ni, Pb, V, and Zn), radionuclides, and grain size composition of marine sediments of all three sites were critically reviewed and seafloor bathymetric data were analyzed.

Results and discussion

A critical review of available physical and chemical information of sediments collected from the three marine sites provides a better understanding of the physical and biogeochemical dynamics of large-scale dispersion of contaminants in those areas, as well as new insights in terms of improved sediments management policies with actions of larger scale monitoring of the “buffer zone confining with the national relevance and highly contaminated site to trace inputs and accumulation effects of pollutants deriving from the point-source.

Conclusions

This study demonstrates how the presence of polluted sediments on the coastal areas can have, also after the closure of anthropogenic activities, a potential impact at a large scale. Then to better evaluate the effective impact, we suggest the adoption of a buffer zone contiguous to the national relevance sites (SIN) area. While SINs are optimized to define the state of the art of the near-source pollution, buffer zones may help to outline the rate of delivery of pollutants to the deep sea. Buffer zones must be designed by taking into account the local hydrodynamics, sedimentology, and geomorphology, and should be monitored, even if at a lower resolution, like SINs.

  相似文献   
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83.
DNA polymorphism analysis of hereditary multiple exostoses in horses   总被引:1,自引:0,他引:1  
Genomic DNA polymorphisms obtained by restriction fragment-length polymorphism from healthy horses and horses with hereditary multiple exostoses were analyzed. These DNA were digested by 12 restriction enzymes and were hybridized against 6 isotopically labeled oncogene probes. Hybridization was not detected with the viral oncogene, v-ras, which indicated this oncogene was absent in the equine genome. Oncogenes (c-raf-1, c-fes, c-myb, c-myc, and c-sis) were present and had similar hybridization patterns and signal intensities in DNA from healthy horses and horses with hereditary multiple exostoses. Unique and distinct restriction fragment-length polymorphisms were detected with the c-raf-1 probe only in BamHI- and PstI-digested equine DNA.  相似文献   
84.
: A nine-year-old male entire Labrador was diagnosed with pituitary dependent hyperadrenocorticism. Following seven months of successful mitotane therapy, the dog presented with marked weight gain, seborrhoea and alopecia. Routine clinicopathological analyses revealed marked hypercholesterolaemia. Serum total and free thyroxine (T4) concentrations were below their respective reference ranges. Serum thyroid stimulating hormone (cTSH) concentration was within reference range. TSH and thyrotropin releasing hormone (TRH) response tests revealed adequate stimulation of total T4 in both, and cTSH in the latter test. Magnetic resonance imaging revealed a mass arising from the pituitary fossa, with suprasellar extension. A diagnosis of tertiary hypothyroidism was made. Following four weeks of levothyroxine therapy, circulating cholesterol concentration had declined, weight loss had ensued and dermatological abnormalities had improved. Euthanasia was performed four months later due to the development of neurological signs. A highly infiltrative pituitary adenoma, with effacement of the overlying hypothalamus was identified on post mortem examination. Tertiary hypothyroidism has not been previously reported in dogs.  相似文献   
85.
Antioxidant phytochemicals in fruits and vegetables of a vegetarian diet may account for the reduced risk of aging and stress oxidative associated diseases. In this study, a simple, rapid and accurate new bioassay for the determination of the antioxidant activity of purified or crude plant extracts and thier interactions is described, based on the fluorimetric determination of thiobarbituric acid reactive substances (TBARS) released by UV-B radiated red blood cell (RBC) ghosts. Pure resveratrol, white and red wine and pomegranate juice (PJ) were used as antioxidant source to test the biological method. TBARS production is a function of radiation time, the number of RBC ghosts in the radiated sample and the loaded antioxidant. The antioxidant activity of resveratrol was detected at a submicromolar concentration range [0.02 μg/mL–0.1 μmol/L]. The activity of red wine was almost 10 times higher than that of white wine, and PJ juice had the highest activity. Submaximal protective effects of PJ and red wine were additive.  相似文献   
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88.
Although light is recognized as one of the main factors influencing fruit carotenogenesis, the specific role of UV-B radiation has been poorly investigated. The present work is addressed to assess the molecular events underlying carotenoid accumulation in presence or absence of ultraviolet-B (UV-B) light in tomato fruits of wild-type and high pigment-1 (hp-1), a mutant characterized by exaggerated photoresponsiveness and increased fruit pigmentation. Gene expression analyses indicated that in wild-type fruits UV-B radiation mainly negatively affects the carotenoid biosynthetic genes encoding enzymes downstream of lycopene both in flesh and peel, suggesting that the down-regulation of genes CrtL-b and CrtL-e and the subsequent accumulation of lycopene during tomato ripening are determined at least in part by UV-B light. In contrast to wild-type, UV-B depletion did not greatly affect carotenoid accumulation in hp-1 and generally determined minor differences in gene expression between control and UV-B-depleted conditions.  相似文献   
89.
Quinoa is a pseudocereal from South America that has received increased interest around the world because it is a good source of different nutrients and rich in antioxidant compounds. Thus, this study has focused on the effects of different agronomic variables, such as irrigation and salinity, on the phenolic and saponin profiles of quinoa. It was observed that irrigation with 25% of full water restitution, with and without the addition of salt, was associated with increases in free phenolic compounds of 23.16 and 26.27%, respectively. In contrast, bound phenolic compounds were not affected by environmental stresses. Saponins decreased if samples were exposed to drought and saline regimens. In situations of severe water deficit, the saponins content decreased 45%, and 50% when a salt stress was added. The results suggest that irrigation and salinity may regulate the production of bioactive compounds in quinoa, influencing its nutritional and industrial values.  相似文献   
90.
OBJECTIVES: The aim of this retrospective study was to summarize the most frequent clinical signs, ultrasonographic, and histological findings accompanying scleral rupture as a result of blunt trauma in dogs, cats, and horses. ANIMALS STUDIED AND PROCEDURES: Thirty small animals and three horses diagnosed with scleral rupture resulting from blunt trauma. B-mode ultrasonography was performed on 20 animals. Histopathology was carried out on 18 enucleated globes. RESULTS: In small animals, 80% presented hyphema, 60% subconjunctival hemorrhage, and 53% eyelid and conjunctival swelling. In horses, 100% presented eyelid and conjunctival swelling, 67% hyphema, subconjunctival hemorrhage, and collapsed anterior chamber. Ultrasonographic findings were an area with ill-defined scleral margins (90%), echoic/hyperechoic contents in the anterior and posterior chamber (55%) and in the vitreous (80%). In small animals, scleral rupture location noted on gross examination was: at the posterior pole (4), close to the optic nerve (3), near the limbus (2), and in the dorsal aspect of the globe (1). In horses, the lesion was located at the limbus (3). In small animals, histopathology showed presence of hemorrhage in the anterior, posterior chamber, and vitreous (94%), retinal detachment (94%), choroidal edema and hemorrhages (88%), and choroidal detachment as a result of suprachoroidal hemorrhage (88%). The same lesions were found in the globes of two horses. In small animals, rupture location noted on histopathology was: at the posterior pole (8), close to the optic nerve (4), near the limbus (1), near the ciliary body (1). CONCLUSIONS: The most frequent clinical signs observed were hyphema, subconjunctival hemorrhage, and eyelid and conjunctival swelling. Ultrasonographic findings suggestive for scleral rupture were ill-defined scleral borders and/or echoic/hyperechoic material in the cavities of the globe. On histopathology, lesions severely altering the anatomy of the eye structures were: hemorrhage into the chambers of the globe, subretinal and suprachoroidal hemorrhage leading to retinal and choroidal detachment, respectively. In small animals, the most frequent locations for scleral rupture were the posterior pole and close to the optic nerve, whereas in horses it was the limbus.  相似文献   
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