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91.
Paola Montagnani 《Plant biosystems》2013,147(3):434-462
Summary Observations on growth and development of Salvia longistyla Benth., in several photoperiodic and termoperiodic conditions, both natural and artificial, were performed. The conclusions of my work are the following I° - It has been proved that Salvia longistyla is a typical short-day plant and that its critical point of reaction lies approssimately on the 14 hours, when the average night-temperature is about 18°C; the flowering does not succeed if the night-temperature is decidedly below 15°C. II° - The plant' requires short-day conditions not only for the formation of the flower buds, but also for the subsequent development, i. e. the full bloom; consequently the plant belongs to Eguchi's S. S. class (short day-plant for both the manifestations). III. - Under natural conditions, in our latitude, Salvia longistyla flowers only in Autumn, because only in this season we have suitable photoperiod and concomitantly suitable night-temperature. In Spring, though the day is short, the night-temperature is not sufficiently high; in Winter and in Spring, the flowering is possible only in a warm green-house, with a night-temperature of about 18°C. In orange green-houses Salvia longistyla can continue the flowering begun in Autumn; during Winter and Spring new blooms do not succeed, just because the night-temperature, in such green houses, is never sufficiently high. IV. - We can obtain fruiting only by artificial pollination (lack of natural pollination agency). V. - The basal branches do not flower even in optimal photo- and termoperiodical conditions (which allow apical flowering) on acount of a mechanism of correlative inhibition. VI. - The elongation of the internodes is relatively inhibited at a very long photoperiod, differently from what we observe in most plants. These prerogatives, verified in repeated experiments, are in perfect accordance with the characteristics of the ambient in which the plant is naturally diffused (Mexico). The altitude and latitude of the stations in which the plant has usually been found, have a short photoperiod all year long, and temperatures (also night-temperatures) costantly suitable for a good growth and bloom. The plants, in the natural ambient, are perennial and bushy. The pluri-annuality can be referred to the flowering inhibition of the lateral and basal branches, that takes place in a specimen and that keeps on for a long time, also after the full flowering of the principal axis. The basal shoots show a tendency to the vegetative growth, even though the external conditions are suitable to the flowering of the apical parts of the plant. Therefore we must attribute the pluriannuality of S. longistyla to this correlative flower-inhibiting mechanism. 相似文献
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93.
Daniela Impellizzeri Emanuela Esposito Rosanna Di Paola Akbar Ahmad Michela Campolo Angelo Peli Valeria Maria Morittu Domenico Britti Salvatore Cuzzocrea 《Arthritis research & therapy》2013,15(6):R192
IntroductionN-palmitoylethanolamine (PEA) is an endogenous fatty acid amide belonging to the family of the N-acylethanolamines (NAEs). Recently, several studies demonstrated that PEA is an important analgesic, antiinflammatory, and neuroprotective mediator. The aim of this study was to investigate the effect of co-ultramicronized PEA + luteolin formulation on the modulation of the inflammatory response in mice subjected to collagen-induced arthritis (CIA).MethodsCIA was induced by an intradermally injection of 100 μl of the emulsion (containing 100 μg of bovine type II collagen (CII)) and complete Freund adjuvant (CFA) at the base of the tail. On day 21, a second injection of CII in CFA was administered. Mice subjected to CIA were administered PEA (10 mg/kg 10% ethanol, intraperitoneally (i.p.)) or co-ultramicronized PEA + luteolin (1 mg/kg, i.p.) every 24 hours, starting from day 25 to 35.ResultsMice developed erosive hind-paw arthritis when immunized with CII in CFA. Macroscopic clinical evidence of CIA first appeared as periarticular erythema and edema in the hindpaws. The incidence of CIA was 100% by day 28 in the CII-challenged mice, and the severity of CIA progressed over a 35-day period with a resorption of bone. The histopathology of CIA included erosion of the cartilage at the joint. Treatment with PEA or PEA + luteolin ameliorated the clinical signs at days 26 to 35 and improved histologic status in the joint and paw. The degree of oxidative and nitrosative damage was significantly reduced in PEA + luteolin-treated mice, as indicated by nitrotyrosine and malondialdehyde (MDA) levels. Plasma levels of the proinflammatory cytokines and chemokines were significantly reduced by PEA + luteolin treatment.ConclusionsWe demonstrated that PEA co-ultramicronized with luteolin exerts an antiinflammatory effect during chronic inflammation and ameliorates CIA. 相似文献
94.
Nicola Bizzaro Elena Bartoloni Gabriella Morozzi Stefania Manganelli Valeria Riccieri Paola Sabatini Matteo Filippini Marilina Tampoia Antonella Afeltra Giandomenico Sebastiani Claudia Alpini Vittorio Bini Onelia Bistoni Alessia Alunno Roberto Gerli 《Arthritis research & therapy》2013,15(1):R16
Introduction
The diagnostic, predictive and prognostic role of anti-cyclic citrullinated peptide (CCP) antibodies in rheumatoid arthritis (RA) patients is widely accepted. Moreover, detection of these antibodies in subjects presenting with undifferentiated arthritis (UA) is associated with a significant risk to develop the disease. On the other hand, clinical and prognostic significance of evaluating anti-CCP levels in subjects with inflammatory arthritis at disease onset has not been fully clarified. The goal of this prospective study is to analyze the value and prognostic significance of anti-CCP titer quantification in UA subjects.Methods
Serial anti-CCP assays were measured in 192 consecutive patients presenting with UA lasting less than 12 weeks. Clinical and serological data and arthritis outcome were evaluated every 6 months until two years of follow-up.Results
Anti-CCP positivity, at both low and high titer, and arthritis of hand joints significantly predicted RA at two years, risk increasing in subjects with high anti-CCP titers at baseline. Moreover, time to RA diagnosis was shorter in patients with high anti-CCP2 titers at enrollment with respect to those with low antibody concentration.Conclusions
Presence of anti-CCP antibodies, at both low and high concentration, is significantly associated with RA development in subjects with recent onset UA. However, time interval from the onset of the first symptoms to the fulfilment of the classification criteria appears to be directly related to the initial anti-CCP level. 相似文献95.
Raffaele Saladino Paola Carlucci Claudia Crestini Pietro Tagliatesta Donato Monti Tristano Boschi 《Nucleosides, nucleotides & nucleic acids》2013,32(4-5):1123-1124
Abstract The oxidation of purine derivatives using porphyrins as catalysts and dimethyldioxirane (DMDO) as oxygen atom donor is reported. The regioselectivity of the oxidation was found to be dependent on the presence of a free OH moiety on the N(9)-side chain of the substrate and on the structure of the catalyst. 相似文献
96.
97.
In this contribution the results of a zoogeographical analysis, carried out on the 123 endemic leaf beetle species (Coleoptera: Chrysomelidae) occurring in Italy and its immediately adjacent regions, are reported. To assess the level of faunistic similarity among the different geographic regions studied, a cluster analysis was performed, based on the endemic component. This was done by calculating the Baroni Urbani & Buser’s similarity index (BUB). Finally, a parsimony analysis of endemicity (PAE) was used to identify the most important areas of endemism in Italy. 相似文献
98.
99.
Victoria Ferrero Sílvia Castro Joana Costa Paola Acuña Luis Navarro João Loureiro 《Biological invasions》2013,15(10):2347-2358
Removal of invasive species often benefits biological diversity allowing ecosystems’ recovery. However, it is important to assess the functional roles that invaders may have established in their new areas to avoid unexpected results from species elimination. Invasive animal-pollinated plants may affect the plant–pollination interactions by changing pollinator availability and/or behaviour in the community. Thus, removal of an invasive plant may have important effects on pollinator community that may then be reflected positive or negatively on the reproductive success of native plants. The objective of this study was to assess the effect of removing Oxalis pes-caprae, an invasive weed widely spread in the Mediterranean basin, on plant–pollinator interactions and on the reproductive success of co-flowering native plants. For this, a disturbed area in central Portugal, where this species is highly abundant, was selected. Visitation rates, natural pollen loads, pollen tube growth and natural fruit set of native plants were compared in the presence of O. pes-caprae and after manual removal of their flowers. Our results showed a highly resilient pollination network but also revealed some facilitative effects of O. pes-caprae on the reproductive success of co-flowering native plants. Reproductive success of the native plants seems to depend not only on the number and diversity of floral visitors, but also on their efficiency as pollinators. The information provided on the effects of invasive species on the sexual reproductive success of natives is essential for adequate management of invaded areas. 相似文献
100.