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Dott. Carmelo Battiato 《Plant biosystems》2013,147(3-4):642-647
Summary The Author describes some cases of bandage of vine branchs and bunchs of grapes in a cultivated vine in the form of a bower. About various cases of natural bandage, he retains that these phenomenons cannot well habe a determined origin but various causes possibly have on influence over the manifestation of these abnormal processes about the susceptibility of some subyects towards forms of deviating development. The vine branch's bandage is for the delineated cases, in correlation to the simultaneous development of two vegetative cones from someone bud, with the following conyoined development with two increased together vine branchs, while the bandage of bunchs of grapes springs from the union of floral secondary aces and from very great activity of the productive organs. 相似文献
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Long‐term monitoring of B‐chromosome invasion and neutralization in a population of Prospero autumnale (Asparagaceae) 下载免费PDF全文
Pedro Lanzas Francisco Perfectti Manuel A. Garrido‐Ramos Carmelo Ruíz‐Rejón Mónica González‐Sánchez María Puertas Juan Pedro M. Camacho 《Evolution; international journal of organic evolution》2018,72(6):1216-1224
B chromosomes have been reported in about 15% of eukaryotes, but long‐term dynamics of B chromosomes in a single natural population has rarely been analyzed. Prospero autumnale plants collected in 1981 and 1983 at Cuesta de La Palma population had shown the presence of B chromosomes. We analyze here seven additional samples collected between 1987 and 2015, and show that B frequency increased significantly during the 1980s and showed minor fluctuations between 2005 and 2015. A mother–offspring analysis of B chromosome transmission, at population level, showed significant drive on the male side (kB = 0.65) and significant drag on the female side (kB = 0.33), with average B transmission rate being very close to the Mendelian rate (0.5). No significant effects of B chromosomes were observed on a number of vigor and fertility‐related traits. Within a parasite/host framework, these results suggest that B chromosomes’ drive on the male side is the main pathway for B chromosome invasion, whereas B chromosome drag on the female side might be the main manifestation of host genome resistance in this species. Prospero autumnale thus illuminates a novel evolutionary pathway for B chromosome neutralization by means of a decrease in B transmission through the nondriving sex. 相似文献
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Roberto Manfredini Massimo Gallerani Francesco Portaluppi Raffaella Salmi Franco Chierici Carmelo Fersini 《Chronobiology international》1995,12(1):55-61
The purpose of this study was to assess prospectively the circadian distribution of spontaneous paroxysmal Supraventricular tachycardia (PSVT) in drug-free subjects with no previous history or symptoms and signs of concomitant heart or lung disease. Of 112,424 presumably diurnally active patients admitted to the Emergency Department of a city hospital during a 2-year period (1990-1991), a total of 185 patients were screened with these characteristics. Time of symptom onset was exactly recordable in 177 (75 men and 102 women). Analysis of variance documented a higher incidence in the morning-afternoon hours. Cosinor analysis, although not a perfect method for the time series analysis, verified circadian rhythmicity with afternoon peak times. Our findings suggest that a circadian pattern in intrinsic electrical instability of the heart conduction system exists irrespective of the circadian fluctuations in the pathophysiologic mechanisms of the cardiovascular or lung diseases most frequently associated with PSVT itself. 相似文献
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PbsP,a cell wall‐anchored protein that binds plasminogen to promote hematogenous dissemination of group B Streptococcus 下载免费PDF全文
Marco Buscetta Arnaud Firon Giampiero Pietrocola Carmelo Biondo Giuseppe Mancuso Angelina Midiri Letizia Romeo Roberta Galbo Mario Venza Isabella Venza Pierre‐Alexandre Kaminski Myriam Gominet Giuseppe Teti Pietro Speziale Patrick Trieu‐Cuot Concetta Beninati 《Molecular microbiology》2016,101(1):27-41
Streptococcus agalactiae (Group B Streptococcus or GBS) is a leading cause of invasive infections in neonates whose virulence is dependent on its ability to interact with cells and host components. We here characterized a surface protein with a critical function in GBS pathophysiology. This adhesin, designated PbsP, possesses two Streptococcal Surface Repeat domains, a methionine and lysine‐rich region, and a LPXTG cell wall‐anchoring motif. PbsP mediates plasminogen (Plg) binding both in vitro and in vivo and we showed that cell surface‐bound Plg can be activated into plasmin by tissue plasminogen activator to increase the bacterial extracellular proteolytic activity. Absence of PbsP results in a decreased bacterial transmigration across brain endothelial cells and impaired virulence in a murine model of infection. PbsP is conserved among the main GBS lineages and is a major plasminogen adhesin in non‐CC17 GBS strains. Importantly, immunization of mice with recombinant PbsP confers protective immunity. Our results indicate that GBS have evolved different strategies to recruit Plg which indicates that the ability to acquire cell surface proteolytic activity is essential for the invasiveness of this bacterium. 相似文献
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Evolution of Capsaicinoids in Peter Pepper (Capsicum annuum var. annuum) During Fruit Ripening 下载免费PDF全文
Gerardo F. Barbero Ana C. de Aguiar Ceferino Carrera Ángel Olachea Marta Ferreiro‐González Julian Martínez Miguel Palma Carmelo G. Barroso 《化学与生物多样性》2016,13(8):1068-1075
The evolution of individual and total contents of capsaicinoids present in Peter peppers (Capsicum annuum var. annuum) at different ripening stages has been studied. Plants were grown in a glasshouse and the new peppers were marked in a temporal space of ten days. The extraction of capsaicinoids was performed by ultrasound‐assisted extraction with MeOH. The capsaicinoids nordihydrocapsaicin (n‐DHC), capsaicin, dihydrocapsaicin, homocapsaicin, and homodihydrocapsaicin were analyzed by ultraperformance liquid chromatography (UHPLC)‐fluorescence and identified by UHPLC‐Q‐ToF‐MS. The results indicate that the total capsaicinoids increase in a linear manner from the first point of harvest at ten days (0.283 mg/g FW) up to 90 days, at which point they reach a concentration of 1.301 mg/g FW. The evolution as a percentage of the individual capsaicinoids showed the initial predominance of capsaicin, dihydrocapsaicin, and n‐DHC. Dihydrocapsaicin was the major capsaicinoid up to day 50 of maturation. After 50 days, capsaicin became the major capsaicinoid as the concentration of dihydrocapsaicin fell slightly. The time of harvest of Peter pepper based on the total capsaicinoids content should be performed as late as possible. In any case, harvesting should be performed before overripening of the fruit is observed. 相似文献
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Marilena Gregorini Valeria Corradetti Chiara Rocca Eleonora Francesca Pattonieri Teresa Valsania Samantha Milanesi Nicoletta Serpieri Giulia Bedino Pasquale Esposito Carmelo Libetta Maria Antonietta Avanzini Melissa Mantelli Daniela Ingo Sabrina Peressini Riccardo Albertini Antonio Dal Canton Teresa Rampino 《PloS one》2016,11(2)