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51.
Elisabetta Dallavalle Aldo Zechini D’Aulerio Emanuela Verardi Assunta Bertaccini 《Plant Molecular Biology Reporter》2002,20(3):305-306
Fusarium oxysporum Schlecht. Fr. F. sp.gladioli (FOG) is the most important gladiolus pathogen. One of the most environmentally friendly methods to control its spread is
to use cultivars that are minimally sensitive to the pathogen. Infected corm tissues in more resistant varieties have been
shown to produce suberin layers that inhibit fungal iphae growth. RAPD analysis of genomes from 9 selected gladiolus cvs,
chosen to be the most resistant and sensitive to FOG, were performed to verify DNA polymorphism levels. Total nucleic acid
extraction was carried out with a chloroform-phenol method from tissues of plants in 3 growth stages. RAPD experiments were
performed using 14 primers with varyingTaq polymerases and primer concentrations. Five of the primers tested gave no polymorphic profiles. Five primers produced polymorphic
bands, allowing us to obtain RAPD profiles typical for one or more of the more resistant cvs. All the tested growth stages
provided repeatable results, indicating the reliability of detected polymorphisms. Cloning the more interesting polymorphic
DNA fragments in the future will verify the presence of specific genes related to FOG resistance mechanisms in gladiolus. 相似文献
52.
Matteo Bassetti Maria Merelli Filippo Ansaldi Daniela de Florentiis Assunta Sartor Claudio Scarparo Astrid Callegari Elda Righi 《PloS one》2015,10(5)
BackgroundCandida is an important cause of bloodstream infections (BSI) in nosocomial settings causing significant mortality and morbidity. This study was performed to evaluate contemporary epidemiology, species distribution, antifungal susceptibility and outcome of candida BSI in an Italian hospital.MethodsAll consecutive patients who developed candidemia at Santa Maria della Misericordia University Hospital (Italy) between January 2009 and June 2014 were enrolled in the study.ResultsA total of 204 episodes of candidemia were identified during the study period with an incidence of 0.79 episodes/1000 admissions. C. albicans was isolated in 60.3% of cases, followed by C. parapsilosis (16.7%), C. glabrata (11.8%) and C. tropicalis (6.4%). Of all Candida BSI, 124 (60.8 %) occurred in patients admitted to IMW, 31/204 (15.2 %) in ICUs, 33/204 (16.2%) in surgical units and 16/204 (7.8%) in Hematology/Oncology wards. Overall, 47% of patients died within 30 days from the onset of candidemia. C. parapsilosis and C. glabrata candidemia were associated with the lowest mortality rate (36%), while patients with C. tropicalis BSI had the highest mortality rate (58.3%). Lower mortality rates were detected in patients receiving therapy within 48 hours from the time of execution of the blood cultures (57,1% vs 38,9%, P <0.05). At multivariate analysis, steroids treatment (OR= 0.27, p=0.005) and CVC removal (OR=3.77, p=0.014) were independently associated with lower and higher survival probability, respectively. Candidemia in patients with peripherally inserted central catheters (PICC) showed to be associated with higher mortality in comparison with central venous catheters (CVC, Short catheters and Portacath) and no CVC use. For each point increase of APACHE III score, survival probability decreased of 2%. Caspofungin (OR=3.45, p=0.015) and Amphothericin B lipid formulation (OR=15.26, p=0.033) were independently associated with higher survival probability compared with no treatment. 相似文献
53.
Grooming behaviour is the most common innate behaviour in animals. In rodents, it consists of sequences of movements organized in four phases, executed symmetrically on both sides of the animal and creating a syntactic chain of behavioural events. The grooming syntax can be altered by stress and novelty, as well as by several mutations and brain lesions. Grooming behaviour is known to be affected by alterations of the dopamine system, including dopamine receptor modulation, dopamine alteration in genetically modified animals, and after brain lesion. While a lot is known about the initiation and syntactic modifications of this refined sequence of movements, effects of unilateral lesion of dopamine neurons are unclear particularly regarding the symmetry of syntactic chains. In the present work we studied grooming in mice unilaterally lesioned in the medial forebrain bundle by 6-hydroxydopamine. We found a reduction in completion of grooming bouts, associated with reduction in number of transitions between grooming phases. The data also revealed the development of asymmetry in grooming behaviour, with reduced tendency to groom the contralateral side to the lesion. Symmetry was recovered following treatment with L-DOPA. Thus, the present work shows that unilateral lesion of dopamine neurons reduces self-grooming behaviour by affecting duration and numbers of events. It produces premature discontinuation of grooming chains but the sequence syntax remains correct. This deficient grooming could be considered as an intrinsic symptom of Parkinson’s disease in animal models and could present some similarities with abnormalities of motor movement sequencing seen in patients. Our study also suggests grooming analysis as an additional method to screen parkinsonism in animal models. 相似文献
54.
55.
Monica Scognamiglio Brigida D’Abrosca Assunta Esposito Severina Pacifico Pietro Monaco Antonio Fiorentino 《Phytochemistry Reviews》2013,12(4):803-830
Allelopathy (the chemical based communication among plants) is gaining more and more attention thanks to its likely outcomes in several fields, but it is, in the meantime, a questionable topic, due to a difficult determination. Despite the broad literature, allelopathic interactions are far from being clarified. Conclusive evidence in this field is not a simple find, as this biological activity is governed by a number of different factors. Such an issue can be solved only provided that suitable methods are used. Understanding allelopathy in natural ecosystems may be crucial in order to think about the exploitation of this resource. Mediterranean plants, in particular, have been proven to be a source of natural active compounds. This paper reviews the most outstanding methods used for plant extract or pure metabolite phytotoxic or allelopathic properties determination. Furthermore, it points out the bioactive metabolites reported from plants characteristics of Mediterranean ecosystems. 相似文献
56.
Abstract The annual time course of the water relations of six sclerophylls has been studied with the aim of: a) defining strategies adopted for withstanding summer water stress and b) to check whether their common sclerophyllous habitus could represent a case of convergent evolution devoted to a univocal functional role. In particular, Phillyrea latifolia L. showed to behave like a drought tolerant as indicated by deep summer drop in leaf water potential (Ψ1) to near the full turgor loss point (Ψlp) and in leaf relative water content (RWC) as caused by xylem cavitation. Prunus laurocerasus L. and Laurus nobilis L. showed to be drought avoiding water spenders in that their Ψ1 dropped in summer causing prompt recovery in RWC. This was made possible by low cavitation in their twigs. Ilex aquifolium L. was a typical drought avoiding water saver in that both Ψ1 and RWC remained at very high levels throughout the year. Quercus ilex L. behaved like a drought avoiding water spender which switched to drought tolerance in the warmest period of the year. This was explained by its high vulnerability to cavitation. The extreme heterogeneity of the six species studied suggested that sclerophylly cannot be interpreted as an anatomical feature leading to a specific and unifying functional role, at least as regards drought resistance. 相似文献
57.
58.
Rosa A Pollastro F Atzeri A Appendino G Melis MP Deiana M Incani A Loru D Dessì MA 《Chemistry and physics of lipids》2011,(1):24-32
This study examines the protective effect of arzanol, a pyrone–phloroglucinol etherodimer from Helichrysum italicum subsp. microphyllum, against the oxidative modification of lipid components induced by Cu2+ ions in human low density lipoprotein (LDL) and by tert-butyl hydroperoxide (TBH) in cell membranes. LDL pre-treatment with arzanol significantly preserved lipoproteins from oxidative damage at 2 h of oxidation, and showed a remarkable protective effect on the reduction of polyunsaturated fatty acids and cholesterol levels, inhibiting the increase of oxidative products (conjugated dienes fatty acids hydroperoxides, 7β-hydroxycholesterol, and 7-ketocholesterol). Arzanol, at non-cytotoxic concentrations, exerted a noteworthy protection on TBH-induced oxidative damage in a line of fibroblasts derived from monkey kidney (Vero cells) and in human intestinal epithelial cells (Caco-2), decreasing, in both cell lines, the formation of oxidative products (hydroperoxides and 7-ketocholesterol) from the degradation of unsaturated fatty acids and cholesterol. The cellular uptake and transepithelial transport of the compound were also investigated in Caco-2 cell monolayers. Arzanol appeared to accumulate in Caco-2 epithelial cells. This phenol was able to pass through the intestinal Caco-2 monolayers, the apparent permeability coefficients (Papp) in the apical-to-basolateral and basolateral-to-apical direction at 2 h were 1.93 ± 0.36 × 10−5 and 2.20 ± 0.004 × 10−5 cm/s, respectively, suggesting a passive diffusion pathway. The results of the work qualify arzanol as a potent natural antioxidant with a protective effect against lipid oxidation in biological systems. 相似文献
59.
Corallini F Celeghini C Rizzardi C Pandolfi A Di Silvestre S Vaccarezza M Zauli G 《Journal of cellular physiology》2007,212(1):89-95
To dissect the effect of hyperinsulinemia versus hyperglycemia on TNF-related apoptosis inducing ligand (TRAIL) expression in the macrovascular district, we measured TRAIL mRNA and protein in four groups of animals: streptozotocin (SZT)-induced diabetic rats, vehicle-treated control animals, diabetic rats treated with insulin and non-diabetic rats treated with insulin. While the aortas of diabetic rats did not show significant differences in TRAIL expression with respect to vehicle-treated control animals, the aortas of both diabetic and non-diabetic rats treated in vivo for 16 days with insulin showed a significant decrease in TRAIL expression with respect to either diabetic and control rats. Moreover, in vitro treatment of both rat and human vascular smooth muscle cells (VSMC) with insulin induced the down-regulation of TRAIL protein. While the addition of recombinant TRAIL to rat VSMC promoted the dose-dependent release of bioactive nitric oxide (NO), this effect was significantly counteracted by pre-exposure of VSMC to insulin. These findings suggest that TRAIL might act as an endogenous regulator of the vascular tone and that chronic elevation of insulin might contribute to the vascular abnormalities characterizing type-2 diabetes mellitus by down-regulating TRAIL expression and activity. 相似文献
60.
Poli A Esposito E Orlando P Lama L Giordano A de Appolonia F Nicolaus B Gambacorta A 《Systematic and applied microbiology》2007,30(1):31-38
The taxomony of strain CRSS (DSM 15686(T)=ATCC BAA-848(T)) isolated from Cape Russell in Antarctica (Ross Sea, 74 52.35 S 163 53.03 E) was investigated in a polyphasic approach. The morphological, physiological and genetic characteristics were compared with that of related species of the genus Halomonas. The isolate grew optimally at pH 9.0, 10% NaCl at 30 degrees C. The cells were Gram-negative aerobic rods able to produce exopolysaccharide. They accumulated glycine-betaine, as a major osmolyte, with minor components ectoine and glutamate. The strain CRSS biosynthetised alpha-glucosidase. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol as major components. Ubiquinone with nine repetitive unities (Q9) was the only quinone found and the fatty acid composition was dominated by C18:1 (53%). The G+C content of DNA was 55.0mol% and its phylogenetic position was established by 16S rRNA gene sequencing as a member of the genus Halomonas. For physiological, chemotaxonomic and genetic features (DNA-DNA hybridisation) it is proposed to classify the isolate as a new species for which we propose the name Halomonas alkaliantarctica sp. nov. 相似文献