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41.
Claudio De Liberato Federica Berrilli Teresa Boss Adele Magliano Margherita Montalbano Di Filippo David Di Cave Mariano Sigismondi Annunziata Cannavacciuolo Paola Scaramozzino 《Zoonoses and public health》2019,66(4):377-381
Swimmer's itch is caused by the penetration of free‐swimming larvae of trematodes of the family Schistosomatidae in human skin. It is usually reported in people engaged in recreational water activities in freshwater bodies and in most of cases, it is provoked by bird schistosomes of the genus Trichobilharzia. In the summer 2017, many cases of dermatitis were recorded in people bathing in the waters of the Albano Lake (Rome, Italy) and a parasitological investigation was carried out in order to ascertain the causative agent of these cases. Snails of the family Lymnaeidae, natural intermediate hosts of bird schistosomes, were collected from lake shallow waters to detect the presence of trematodes of the genus Trichobilharzia. Pools of maximum 10 snails were placed in Petri dishes, and cercarial emergence was stimulated exposing snails to strong artificial light intensity at 25°C. Three hundred and thirty‐seven snails were collected and screened for the shedding of cercariae. Furcocercariae of the family Schistosomatidae, with a morphology overlapping that of the genus Trichobilharzia, were detected in seven Petri dishes. Assuming that in each positive Petri dish just one snail was shedding furcocercariae, the minimum infectious rate was 2.1%. Molecular analysis of furcocercariae allowed ascribing them to the species Trichobilharzia franki. Snails of the species Radix auricularia were identified as intermediate hosts of the parasite. This is the second record of T. franki causing cercarial dermatitis in Central Italy, the third in Italy. The 2017 was in Italy exceptionally warm and dry. Trematodes are sensitive to changes in temperature, being cercarial production and emission rates temperature dependent. Small increases in water temperature would speed up parasite development and transmission, leading to a manifold increase in cercarial emergence. Moreover, high temperatures raise chances to acquire the infection, due to increased time spent in water by people. 相似文献
42.
Drought, salinity and forest fires are adverse abiotic factors responsible for the failure of plant regeneration in the Mediterranean
regions. The objective of this study was to evaluate Pinus pinea seed germination in response to heat, osmotic and salinity stress. Separate experiments were conducted, using polyethylene
glycol (PEG) as an osmotic agent to reproduce drought stress, and sodium chloride (NaCl) and diluted seawater as salinizing
agents to simulate salinity stress. Different temperatures were used to reproduce the effects of different fire regimes. Seed
germination and the activities of the main enzymes involved in Pinus seed reserve utilization (glyoxylate cycle enzymes) decreased with increasing PEG, NaCl and seawater concentrations. Seawater
appears to be the least toxic salinizing agent on Pinus pinea seed germination. The present study indicates that the germination of Pinus pinea seeds is influenced by the concentrations and even more by the nature and interactions of the ions present in the solutions.
As regard heat treatments, the maximum germination percentage (80%) was obtained at 80°C and short exposure time (3 min).
Increasing exposure time and temperature led to the germination percentage progressively decreasing. 相似文献
43.
Giovanna Settineri Carmelo Mallamaci Miroslava Mitrović Maria Sidari Adele Muscolo 《European Journal of Forest Research》2018,137(2):131-141
This study investigated, in a Pinus laricio forest of south Italy, how systematic thinning of different intensities (intense thinning, T45; moderate thinning, T25; clear cut, CC; and no thinning, T0) affected soil biological properties, organic matter trend and carbon (C) storage in soil and plants. Soil carbon content and carbon/nitrogen (C/N) ratio were significantly higher in the T45 than in control, T25 and CC. Under T45, the soils had also the highest enzymatic activities, microbial biomass carbon (MBC) and colonies of fungi and bacteria. The humification parameters (humification ratio, HR; the degree of humification, DH; humification index, HI) indicated T45 as the best silvicultural practice-approach method to manage Pinus laricio forest for increasing soil carbon storage. The dendrometric parameters evidenced that T45 caused the greatest increment in wood growth (diameter and height), showing that the positive effect of the intense systematic thinning (T45) on the mechanical stability of plantation was related to the ability of trees to accumulate large amounts of carbon in their wood tissues. These data were confirmed by wood density value that was the highest in pine trees under the T45. This study showed that in Pinus laricio forest under T45 C stock increased in soil and plant, already 4 years after thinning. 相似文献
44.
Agnieszka Piernik Katarzyna Hrynkiewicz Anna Wojciechowska Sonia Szymańska Marta Izabela Lis Adele Muscolo 《Archives of Agronomy and Soil Science》2017,63(10):1404-1418
The aim of this study was to determine the influence of selected halotolerant endophytic bacteria isolated from the roots of Salicornia europaea on the growth parameters of Beta vulgaris under different concentrations of salinity. Two endophytic strains were selected as inocula for the pot experiment: Pseudomonas sp. ISE-12 (B1) and Xanthomonadales sp. CSE-34 (B2). Surface-sterilised seeds were incubated in the bacterial inoculation suspensions before sowing and cultivated in a sterile mixture of sand and vermiculite (1:1). Six salinity treatments were taken into account: 0, 50, 100, 150, 200 and 300 mM NaCl. Inoculation of seeds with B1 and B2 positively affected germination percentage and germination index and shortened mean germination time, which led to a quickening of the growth stages of seedlings. After 42 days inoculated plants had, in general, a greater root length, higher dry biomass, lower tissue water content and lower specific leaf area compared with the control. While the positive effect of B2 bacteria was visible only at low salinity, strain B1 stimulated plant growth at higher salinities (200 and 300 mM NaCl). We suggest that the superior growth promotion observed for B1 may be related to the higher metabolic activity of these bacteria. 相似文献
45.
Helena Gaspar Adele Cutignano Laura Grauso Nuno Neng Vasco Cachatra Angelo Fontana Joana Xavier Marta Cerejo Helena Vieira Susana Santos 《Marine drugs》2016,14(10)
Among marine organisms, sponges are the richest sources of pharmacologically-active compounds. Stemming from a previous lead discovery program that gathered a comprehensive library of organic extracts of marine sponges from the off-shore region of Portugal, crude extracts of Erylus cf. deficiens collected in the Gorringe Bank (Atlantic Ocean) were tested in the innovative high throughput screening (HTS) assay for inhibitors of indoleamine 2,3-dioxygenase (IDO) and showed activity. Bioassay guided fractionation of the dichloromethane extract led to the isolation of four new glycolipids, named erylusamide A–D. The structures of the isolated compounds were established by 1D and 2D nuclear magnetic resonance (NMR) spectroscopy, high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) and chemical derivatization. The metabolites shared a pentasaccharide moiety constituted by unusual highly acetylated d-glucose moieties as well as d-xylose and d-galactose. The aglycones were unprecedented long chain dihydroxyketo amides. Erylusamides A, B and D differ in the length of the hydrocarbon chain, while erylusamide C is a structural isomer of erylusamide B. 相似文献
46.
The wheat microsatellite XGWM261 is of interest to wheat breeders because of its linkage to a commercially significant reduced
height gene (Rht8). Previous studies have indicated that there are three major alleles at the XGWM261 locus and that the majority (90%) of
varieties are homozygous, generating PCR products of 192,174, or 165 bp. As a preliminary investigation of heterozygosity
and sequence variation at the XGWM261 locus in Australian wheat varieties, we cloned and sequenced PCR products from 24 hexaploid
varieties of significance in Australian breeding programmes. Three major alleles of 192, 174 and 164 bp were found, but a165
bp allele was not detected. Prior genotyping via electrophoretic methods had indicated that 2 of the 24 (8%) varieties were
heterozygous. Our results indicate that 6 varieties (25%) carry 2 or more of the major alleles. It is not clear whether this
results from heterozygosity within individual seeds, or from heterogeneity of breeding stocks. With respect to the microsatellite
region itself, we found that the 174 bp and 164 bp alleles actually represent (CT)11AG and (CT)6AG motifs (respectively) rather than(CT)12 and (CT)7. This finding has diagnostic potential. A further 2 varieties also carry an interrupted (CT)nCC(CT)n microsatellite not previously recorded. It is unclear whether this represents a separate allelic lineage or is simply the
result of replication error.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
47.
Locomotor primitives in newborn babies and their development 总被引：1，自引：0，他引：1
Dominici N Ivanenko YP Cappellini G d'Avella A Mondì V Cicchese M Fabiano A Silei T Di Paolo A Giannini C Poppele RE Lacquaniti F 《Science (New York, N.Y.)》2011,334(6058):997-999
How rudimentary movements evolve into sophisticated ones during development remains unclear. It is often assumed that the primitive patterns of neural control are suppressed during development, replaced by entirely new patterns. Here we identified the basic patterns of lumbosacral motoneuron activity from multimuscle recordings in stepping neonates, toddlers, preschoolers, and adults. Surprisingly, we found that the two basic patterns of stepping neonates are retained through development, augmented by two new patterns first revealed in toddlers. Markedly similar patterns were observed also in the rat, cat, macaque, and guineafowl, consistent with the hypothesis that, despite substantial phylogenetic distances and morphological differences, locomotion in several animal species is built starting from common primitives, perhaps related to a common ancestral neural network. 相似文献
48.
During meiosis, two chromosome segregation phases follow a single round of DNA replication. We identified factors required to establish this specialized cell cycle by examining meiotic chromosome segregation in a collection of yeast strains lacking all nonessential genes. This analysis revealed Sgo1, Chl4, and Iml3 to be important for retaining centromeric cohesin until the onset of anaphase II. Consistent with this role, Sgo1 localizes to centromeric regions but dissociates at the onset of anaphase II. The screen described here provides a comprehensive analysis of the genes required for the meiotic cell cycle and identifies three factors important for the stepwise loss of sister chromatid cohesion. 相似文献
49.
Papetti A Pruzzo C Daglia M Grisoli P Bacciaglia A Repetto B Dacarro C Gazzani G 《Journal of agricultural and food chemistry》2007,55(2):278-284
Some beverages and foods protect tooth surfaces against Streptococcus mutans colonization. Adhesion of S. mutans is a crucial step in the initiation and development of dental caries. In this study, we showed that barley coffee (BC), a beverage made from roasted barley, interferes with S. mutans adsorption to hydroxyapatite (HA), and we identified its antiadhesive components. The effects of sublethal concentrations (sub-MICs) of BC on the adhesion of S. mutans to saliva-coated HA beads were assessed using three experimental approaches: (A) Beads were pretreated with BC before adding bacteria, (B) BC and bacteria were added to the beads simultaneously, and (C) streptococci grown in the presence of sub-MICs of BC were added to the beads. All treatments induced variable but significant inhibition of S. mutans sucrose-dependent and -independent adherence to HA. Similar results were obtained with other oral streptococci. BC components were fractioned by dialysis and gel filtration chromatography; the <1000 Da molecular mass (MM) fraction, which contains polyphenols, zinc, and fluoride ions, and the >1000 kDa MM fraction, which consists of a potent brown antioxidant, melanoidin, both displayed antiadhesive properties. High-MM melanoidin was not detected in unroasted barley, indicating that it forms during the roasting process. Results suggest that BC consumption may influence the colonization of tooth surfaces by cariogenic bacteria. 相似文献