Search results for "dent"
showing 10 items of 16910 documents
Condition-dependent ecdysis and immunocompetence in the amphipod crustacean, Gammarus pulex.
2010
The exoskeleton of arthropods forms an efficient protection against pathogens, but this first line of defence is periodically weakened during ecdysis, increasing the opportunity for surrounding pathogens to invade the body cavity. Since the richness of pathogens in the environment can be spatially and temporally variable, arthropods may have a fitness advantage in moulting in a place and time of low infection risk. Consistent with this hypothesis, we found that the amphipod crustacean, Gammarus pulex , exhibits temporal adjustment of the moult cycle in response to elevated risks of infection. Interestingly, this phenomenon is variable between two populations and independent of levels of im…
Holocephalan (Chondrichthyes) dental plates with hypermineralized dentine as a substitute for missing teeth through developmental plasticity.
2020
All extant holocephalans (Chimaeroidei) have lost the ability to make individual teeth, as tooth germs are neither part of the embryonic development of the dental plates, nor of their continuous growth. Instead, a hypermineralized dentine with a unique mineral, whitlockin, is specifically distributed within a dentine framework into structures that give the dental plates their distinctive, species-specific morphology. Control of the regulation of this distribution must be cellular, with a dental epithelium initiating the first outer dentine, and via contact with ectomesenchymal tissue as the only embryonic cell type that can make dentine.\ud Chimaeroids have three pairs of dental plates with…
Taxonomic revision of Riella subgenus Trabutiella (Riellaceae, Sphaerocarpales)
2014
The genus Riella (Riellaceae, Sphaerocarpales) includes some 24 species of thalloid aquatic liverworts with unique morphological and ecological features among hepatics. These include the development of sporophytes enclosed within involucres and growing submerged in seasonal fresh or brackish water ponds. Riella subgenus Trabutiella includes species with winged involucres. Seven taxa have been described, however, four to five taxa have been recognized at a time depending on authors. In this study we have conducted a morphological revision of the species of this subgenus, based on 59 traits measured under light and Scanning Electron Microscopy analyses and that were the subject of statistical…
DNA-Based Identification of Larvae Offers Insights into the Elusive Lifestyles of Native Olive Seed Wasps in South Africa
2020
Wild and cultivated olives in the Western Cape of South Africa are direct or indirect hosts to a high diversity of Braconidae and Chalcidoidea wasps. Olive-associated Braconidae are known to parasitise the larvae of Bactrocera oleae (Rossi), and probably also Bactrocera biguttula (Bezzi). The lifestyle of olive-associated Chalcidoidea is not fully understood, and may include phytophagous, parasitoid and hyperparasitoid species. Some chalcids could represent olive seed wasps (OSW), a generic term that designates the seed feeders responsible for losses in commercial olive production. In order to obtain direct DNA-based evidence for the lifestyle of four putative OSW – Eupelmus spermophilus Si…
Positive effect of platelet rich fibrin on osseointegration
2016
Background Leukocyte-platelet rich fibrin (L-PRF) is a second generation platelet concentrate clinically used to accelerate tissue healing and bone regeneration. Achieving reduced implant osseointegration time could provide immediate or early loading of implants. The aim of this study was to evaluate the L-PRF-induced osseointegration and bone-implant contact (BIC) in an experimental animal model. Material and Methods Twelve 4-month-old New Zealand white rabbits were used. Following general anesthesia, 3-5 mL of blood was obtained from the central artery in rabbit ear and L-PRF was prepared. Two implant cavities (5 mm long and 3 mm in diameter) were created in each tibia with a total of fou…
Activation of MAPK homologues by elicitors in tobacco cells
1998
Elicitors of plant defence reactions (such as cryptogein, an elicitin produced by Phytophthora cryptogea, or oligogalacturonides (OGs)), induced in tobacco cell suspensions (Nicotiana tabacum var Xanthi) a rapid and transient activation of two protein kinases (PKs) with apparent molecular masses of 50 and 46 kDa, respectively. These PKs activated and phosphorylated at tyrosine residues, phosphorylated myelin basic protein (MBP) at serine/threonine residues. Both are recognized by anti-MAPK antibodies. The two MBP kinases possessed the same kinetics of activation, and their activation depended, to the same extent, on different exogenously applied compounds (staurosporine, lanthanum, EGTA). W…
Palaearctic species of Charipinae (Hymenoptera, Figitidae): two new species, synthesis and identification key
2018
The Charipinae Dalla Torre & Kieffer, 1910 present in the Palaearctic region are revised; 2410 specimens have been identified, belonging to 75 species: 52 to Alloxysta, one to Apocharips, six to Dilyta and 16 to Phaenoglyphis. For 33 species, new country-level distribution records are provided. Two new species are here described: Alloxysta palearctica Ferrer-Suay & Pujade-Villar sp. nov. and Alloxysta pascuali Ferrer-Suay sp. nov. A diagnosis for these species is included and their diagnostic features are shown in different figures. A key to identify all the species of Charipinae in the Palaearctic region is also given.
Charipinae (Hymenoptera: Cynipoidea: Figitidae) present in the Museum of Natural History of the University of Wroclaw, with an identification key for…
2020
Charipinae (Cynipoidea: Figitidae) deposited in the Museum of Natural History of Wroclaw University (Poland) have been studied. Seven species are recorded for the first time from Poland: Alloxysta brachyptera (Hartig, 1840), A. castanea (Hartig, 1841), A. citripes (Thomson, 1862), A. consobrina (Zetterstedt, 1838), A. mullensis (Cameron, 1883), A. nottoni Ferrer-Suay & Pujade-Villar, 2015 and Phaenoglyphis heterocera (Hartig, 1841). The presence of previously recorded species is confirmed and new records are specified. A key to all Charipinae species ever recorded in Poland is given.
Arginase induction represses gall development during clubroot infection in Arabidopsis.
2012
Arginase induction can play a defensive role through the reduction of arginine availability for phytophageous insects. Arginase activity is also induced during gall growth caused by Plasmodiophora brassicae infection in roots of Arabidopsis thaliana; however, its possible role in this context has been unclear. We report here that the mutation of the arginase-encoding gene ARGAH2 abrogates clubroot-induced arginase activity and results in enhanced gall size in infected roots, suggesting that arginase plays a defensive role. Induction of arginase activity in infected roots was impaired in the jar1 mutant, highlighting a link between the arginase response to clubroot and jasmonate signaling. C…
Incidental catch of loggerhead sea turtles (Caretta caretta) along the Sicilian coasts by longline fishery
2018
It has been estimated that 44,000 Caretta caretta turtles die every year due to anthropomorphic activity in the Mediterranean Sea, and that longline fishing is one of the most significant causes of mortality. A total of 482 specimens of C. caretta were rescued from different parts of the Sicilian coast (Mediterranean Sea) from 2014 to 2016. The most numerous stranding was recorded during the spring and summer seasons, mainly along the north and eastern coasts of Sicily. The curved carapace length for all the specimens ranged from between 19 and 95 cm and most of these were young or sub adults. The highest number of strandings was recorded in 2014 and 2015, with 206 and 169 individuals, resp…