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Carmen Arena Lucia Santorufo Pia Rosa Cataletto Valeria Memoli Rosaria Scudiero Giulia Maisto 《Water, air, and soil pollution》2017,228(12):459
Plants of the urban environment are exposed to a wide range of pollutants, including heavy metals. This research studies in situ the eco-physiological and antioxidant responses of holm oak (Q. ilex) leaves to Pb and Cd to assess the mechanisms of metal tolerance in this species, widely used as biomonitor. Leaves of plants grown at parks and roadsides were analyzed for photosynthetic activity, Pb and Cd concentration in tissues and cell-free extracts, thiol groups, D1 and Rubisco protein content, ascorbic acid (AsA) amount, and catalase (CAT) activity. The main results evidenced that Cd concentration was higher in leaves collected at the park out from the downtown; whereas Pb was most abundant in leaves sampled at the roadside nearby the highway. Pb in cell-free extracts was higher in park than in roadside leaves. Although Cd in the leaf tissues was twofold lower than Pb, it was more abundant than Pb in cellular extracts deprived of all particulate matter. Leaves responded to different concentration of Cd and Pb modulating some eco-physiological and biochemical traits, roadside leaves showed reduced leaf lamina, higher content of photosynthetic pigments, hydrogen peroxide, and AsA, as well as higher CAT activity compared to park leaves. In the roadside leaves, a stress condition for photosynthetic apparatus can be hypothesized on the basis of the decline of photochemical activity, the increase of NPQ, and the reduction of Rubisco and D1 protein content. The elevated presence of thiol groups in these leaves suggests a possible role of Pb and Cd in activation of antioxidant responses. 相似文献
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Giulia Alberoni Marina Collina Catherine Lanen Pierre Leroux Agostino Brunelli 《European journal of plant pathology / European Foundation for Plant Pathology》2010,128(2):171-184
In Stemphylium vesicarium, four phenotypes were recognized according to their in vitro responses to dicarboximide fungicides: S (sensitive), S+ (low resistant to iprodione and procymidone but moderately resistant to vinclozolin), R1 (moderately resistant to iprodione and vinclozolin but highly resistant to procymidone), R2 (highly resistant to all dicarboximides). Cross-resistance was observed between dicarboximides and aromatic hydrocarbon fungicides
in all cases while cross-resistance to phenylpyrroles was only detected in R2 phenotype. Moreover, no changes were noted in sensitivity to oxidative and osmotic stress inducers. An osmosensing histidine
kinase gene, homologous to OS1 from Neurospora crassa, was sequenced from several field isolates of Stemphylium vesicarium. This gene is predicted to encode a 1,329 amino acid protein, comprising a conserved histidine-kinase domain in the C-terminal
region and six tandem repeats of about 90 amino acids at the N-terminal end. In S+ and R1 phenotype isolates, a single amino acid substitution was observed in the first amino acid repeat; F267L and L290S respectively.
For the R2 isolates, the exchanges T765R or Q777R were located within the histidine-kinase domain. 相似文献
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Seeds of wild asparagus (Asparagus acutifolius L.) were treated and compared in this research to investigate seed dormancy class and level involved in this species. Four seed lots were compared: (i) freshly harvested seeds in 2007 (07Fr); (ii) freshly harvested seeds in 2008 (08Fr); (iii) after-ripened (AR) 2007 seeds dry stored in glass jars (ARg); (iv) AR 2007 seeds dry stored in paper bags (ARp). The 07Fr seeds were exposed to (1) chemical scarification combined with gibberellic acid (GA3) levels (0, 200, 400, and 600 mg L−1) and to (2) 28-day moist stratification at 5 and 23 °C, and two sequences of 5/23 °C combined with 0 and 400 GA3 mg L−1 levels, and (3) together to the 08Fr and AR seeds were exposed to 56-day moist stratification at 5, 23, or 5/23 °C. With the 08Fr and AR seed lots this last stratification treatment was combined with 0 or 800 GA3 mg L−1 levels. The dormancy depth of 08Fr (32% germination) was less than 07Fr seeds (2%). The latter after-ripened during dry storage and when stored in glass germinated more (47.5%) than in paper (12%). Stratification for 4 weeks was ineffective in improving germination of 07Fr seeds; when chemically scarified they did not germinate at all. The highest (nearly 70%) and the most rapid and uniform germination were observed for all the lots when they were warm stratified for 56 days. Warm stratification improved germination more than alternate temperature stratification, while cold stratification inhibited germination especially for the 08Fr and ARg lots, thus seeds seem not to have a morphological component to their dormancy. GA3 only improved germination of 07Fr seeds, at a low rate. A. acutifolius seeds fit the characteristics of a non-deep physiological dormancy. 相似文献
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Massimo Trabalza-Marinucci Giorgio Brandi Cristina Rondini Luca Avellini Camilla Giammarini Silva Costarelli Gabriele Acuti Chiara Orlandi Giovanni Filippini Elisabetta Chiaradia Manuela Malatesta Silvia Crotti Chiara Antonini Giulia Amagliani Elisabetta Manuali Anna Rita Mastrogiacomo Livia Moscati Mohamed Naceur Haouet Alberto Gaiti Mauro Magnani 《Livestock Science》2008,113(2-3):178-190
This study shows that a diet including insect-resistant Bt176 maize, fed to 53 ewes and their progeny for 3 years, did not have adverse effects on their health or performance and that no horizontal gene transfer to ruminal microorganisms or animal tissues was detected. No differences were observed regarding performance, reproductive traits, haematological parameters, antioxidant defences, lymphocyte proliferative capacity, phagocytosis and intracellular killing of macrophages, and ruminal microbial population characteristics between control and genetically modified (GM) maize-fed animals. Immune response to Salmonella abortus ovis vaccination was more efficient in GM maize fed sheep. No modifications of histological features of tissues were found; however, cytochemical analyses of ruminal epithelium by Ki67 staining provided evidence of proliferative activation of basal cells in all GM maize-fed ewes. Preliminary electron microscopy analyses of the liver and pancreas revealed smaller cell nuclei containing increased amounts of heterochromatin and perichromatin granules in GM maize-fed lambs. Meat protein content and water loss by cooking were slightly affected by the dietary treatment. No transgenic DNA was detected in tissues, blood, and ruminal fluid or ruminal bacteria. Longitudinal studies should be included in evaluation of food safety whenever possible and sheep may be a useful animal model for toxicological assessment. 相似文献
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Context
Theory predicts that habitat loss and fragmentation may have drastic consequences on species’ interactions. To date, however, little empirical evidence exists on the strength of interspecific competition in shaping animal communities in fragmented landscapes.Objectives
Our aim was to measure the degree of ongoing competitive interference between species in fragmented landscapes. Our model system was the community of ground-dwelling rodents in deciduous woodlands in central Italy, composed of a habitat generalist species (Apodemus sylvaticus) and two forest specialists (Apodemus flavicollis and Myodes glareolus). Our objectives were to test whether species were segregated among forest patches and whether spatial segregation was determined by interspecific competition or habitat and resource availability.Methods
We surveyed the populations inhabiting 29 woodland patches in a highly fragmented landscape using a capture-mark-recapture protocol, capturing >4500 individuals. First we modelled species’ distribution as a function of habitat, resource availability and landscape variables. The second stage of our analyses involved measuring the response of vital rate parameters (body mass, reproduction, survival, recruitment, population density) to competitor density.Results
The relative distribution of species reflected a spatial segregation of habitat generalists and specialists according to habitat quality, cover and connectivity. Interspecific competition mainly affected individual level vital rates, whereas we found no substantial effects at the population level.Conclusions
Competitive exclusion of specialist species by generalist species was occurring. However, when compared to other factors such as habitat connectivity and resource availability, interspecific competition played a relatively minor role in shaping the studied community.49.
Marco Cunto Elisa Mariani Eleonora Anicito Guido Giulia Ballotta Daniele Zambelli 《Reproduction in domestic animals》2019,54(6):815-822
In small animal practice, prostatic diseases are increasingly encountered. All dogs may experience prostatic disease, but particular care should be addressed to breeding dogs, in which prostatic affection may lead to decrease in semen quality and fertility. The most common prostatic disease is the benign prostatic hyperplasia (BPH) followed by prostatitis, prostatic neoplasia and prostate squamous metaplasia. These diseases do not have pathognomonic symptoms, therefore, making a correct diagnosis may not be easy. An accurate clinical examination and a correct diagnostic protocol are essential in order to begin the most appropriate treatment, and also to do a good prophylaxis where it is possible. BPH therapy is usually recommended when mild‐severe signs are present or if symptoms disturb the patient. New therapeutic approaches, both medical and surgical, allow to maintain fertility in most animals with prostatic disorders. Prostate cancer is relatively infrequent. Elective therapy is the surgical one, but it is considered palliative and can result in important post‐operative complications. The aim of this paper is to lay down the most appropriate diagnostic process describing the aetiologies of prostatic disease, their symptoms, the right investigative tools and therapy. 相似文献