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Recently, in the province of Trapani (Western Sicily), some overwintering specimens of the argasid tick Argas (Persicargas) persicus (Oken, 1818) were observed and collected. Morphological and genetic analysis were utilized in order to reach a definitive identification. The species was found in two semi-natural sites where, having been found repeatedly, its presence does not appear accidental. Moreover the characteristics of the Sicilian findings seem to exclude a human-induced spread. This record, the first regarding Sicily and South Italy, is discussed together with the previous doubtful citations for Italy. These findings revalue not only all the old citations for Italy but also the hypothesis that the Mediterranean distribution of this argasid is of a natural origin.

The sensitivity of freshwater invertebrates to agricultural pollutants is supposed to increase with rising temperature due to global warming. The aim of this study was to measure the effect of temperature on the lethal toxicity of ammonia-N, the herbicide Imazamox and the mixture of the two chemicals, in the adults and the juveniles of a population of the copepod Eucyclops serrulatus. This is a widely distributed species found in surface waters, in transitional habitats between surface water and groundwater, and in genuine groundwater environments. We tested the sensitivity by short-term bioassays (96 h) at 15°C and 18°C, respectively. Our results highlighted the following: (1) increasing temperature affected the sensitivity of the adults to ammonia-N and of the juveniles to the mixture, all of which were more sensitive to its detrimental effects at 18°C; (2) the juvenile stages were more sensitive than the adults to all toxicants, and (3) for all combinations of chemicals and temperatures, the effects were synergistic and approximately one order of magnitude greater than those expected according to a concentration addition model when comparing the LC50 for each chemical in the mixture with the LC50s of chemicals individually assayed. Overall, in a context of global change, ammonia-N and mixtures of agricultural pollutants may affect the survival rate of species that spend a part or the whole life-cycle in the hyporheic habitat, with detrimental effects to biodiversity and ecosystem services provided by the hyporheic biota. [ABSTRACT FROM AUTHOR]

Reduced metabolic rates of groundwater taxa, compared to those of surface water species, have long been inferred to be an adaptive trait where there is a low and discontinuous food supply and unpredictable shifts between hypoxic and normoxic conditions. However, there have been neither measurements of the respiratory rate of groundwater copepods nor a comparison of rates between closely related groundwater and surface water species., We measured the metabolic rates of two species of Cyclopoida: Cyclopidae, the stygobiotic (hypogean) copepod Diacyclops belgicus and the epigean Eucyclops serrulatus, which co-occur in the same alluvial aquifer. We expected the metabolic rate of the hypogean to be lower than that of the epigean species, irrespective of the ontogenetic stage, which would be consistent with the hypothesis that there is a generally lower metabolic rate in groundwater species., The metabolic rate of D. belgicus was significantly lower than that of the epigean E. serrulatus irrespective of the ontogenetic stage. We found an allometric relationship between oxygen consumption and body mass for E. serrulatus, an isometric one for D. belgicus juveniles and a rate of oxygen consumption that apparently does not change systematically with body mass for D. belgicus adults., The low metabolic rate of D. belgicus may be advantageous in oligotrophic groundwater habitats, where large fluctuations in oxygen availability occur. However, these physiological adaptations can put hypogean species at risk of replacement by more metabolically active epigean taxa, whenever the availability of organic matter increases, as happens with organic pollution. Moreover, the low metabolic rate of the hypogean species may entail an inability to cope with toxicants, rendering them more sensitive to pollutants. A higher metabolic rate in juvenile D. belgicus compared to that of adults allows copepodids to mature quickly when food is briefly abundant. [ABSTRACT FROM AUTHOR]

Previous results provided evidence that Cratylia mollis seed lectin (Cramoll 1,4) promotes Trypanosoma cruzi epimastigotes death by necrosis via a mechanism involving plasma membrane permeabilization to Ca2+ and mitochondrial dysfunction due to matrix Ca2+ overload. In order to investigate the mechanism of Ca2+-induced mitochondrial impairment, experiments were performed analyzing the effects of this lectin on T. cruzi mitochondrial fraction and in isolated rat liver mitochondria (RLM), as a control. Confocal microscopy of T. cruzi whole cell revealed that Cramoll 1,4 binding to the plasma membrane glycoconjugates is followed by its internalization and binding to the mitochondrion. Electrical membrane potential (∆Ψm) of T. cruzi mitochondrial fraction suspended in a reaction medium containing 10 μM Ca2+ was significantly decreased by 50 μg/ml Cramoll 1,4 via a mechanism insensitive to cyclosporine A (CsA, membrane permeability transition (MPT) inhibitor), but sensitive to catalase or 125 mM glucose. In RLM suspended in a medium containing 10 μM Ca2+ this lectin, at 50 μg/ml, induced increase in the rate of hydrogen peroxide release, mitochondrial swelling, and ∆Ψm disruption. All these mitochondrial alterations were sensitive to CsA, catalase, and EGTA. These results indicate that Cramoll 1, 4 leads to inner mitochondrial membrane permeabilization through Ca2+ dependent mechanisms in both mitochondria. The sensitivity to CsA in RLM characterizes this lectin as a MPT inducer and the lack of CsA effect identifies a CsA-insensitive MPT in T. cruzi mitochondria. [ABSTRACT FROM AUTHOR]

Widespread pollution from agriculture is one of the major causes of the poor freshwater quality currently observed across Europe. Several studies have addressed the direct impact of agricultural pollutants on freshwater biota by means of laboratory bioassays; however, as far as copepod crustaceans are concerned, the ecotoxicological research is scarce for freshwater species and almost nonexistent for the hypogean ones. In this study, we conducted a comparative analysis of the available literature data on the sensitivity of freshwater copepods to agricultural pollutants. We also assessed the acute and chronic sensitivity of a hypogean and an epigean species, both belonging to the Crustacea Copepoda Cyclopoida Cyclopidae, to two N-fertilizers (urea and ammonium nitrate) and two herbicides (ARIANE II from Dow AgroSciences LLC, and Imazamox), widely used for cereal agriculture in Europe. According to the literature review, freshwater copepods are sensitive to a range of pesticides and N-fertilizers. Ecotoxicological studies on hypogean species of copepods account only one study. There are no standardized protocols available for acute and chronic toxicity tests for freshwater copepods, making comparisons about sensitivity difficult. From our experiments, ionized ammonia proved to be more toxic than the herbicide Imazamox, in both short and chronic bioassays. Urea was the less toxic chemical for both species. The hypogean species was more sensitive than the epigean one to all chemicals. For both species and for all tested chemicals, acute lethality and chronic lethality were induced at concentrations higher than the law limits of good water body quality in Europe, except for ionized ammonia, which provoked the chronic lethality of the hypogean species at a lower concentration. The hazardous concentration (HC) of un-ionized ammonia for 5 % of freshwater copepods, obtained by a species sensitivity distribution, was 92 μg l, significantly lower than the HC computed for traditional test species from freshwater environments. [ABSTRACT FROM AUTHOR]

Urban habitats are increasing worldwide and represent new potential environments for many species of animals, in particular birds. As a result of contact with humans, urban wildlife can experience ecological and ethological modifications, mainly regarding parental and feeding behaviour. One of the most common birds in urban landscapes is the mallard, Anas platyrhynchos L., which is widespread in temperate regions. This study aimed to characterize two Italian populations of mallards living in a metropolitan area, from both an ecological and a genetic point of view. Field surveys were carried out for 27 consecutive months along two rivers, focusing on the biological cycle and reproductive behaviour of the mallard. The ecological results were integrated with molecular data, obtained by the analysis of 10 microsatellites, genotyped in the two urban, in a wild and in a captive-bred population. No significant changes in eco-ethological features of the mallards living in the urban area were observed, whereas the urban populations were genetically differentiated from the wild and the bred ones. [ABSTRACT FROM AUTHOR]

Insight regarding the genetic origin and composition of the studied population of the red-legged partridge (Alectoris rufa) is likely to provide general and critical information for the appropriate management and possible conservation of the species. The reintroduced population of red-legged partridges living in Pianosa Island (National Park Tuscany Archipelago) has proven to be sustainable: captive-bred individuals, morphologically assigned to the taxonA. rufa, were released to the island approximately 20 years ago, establishing an apparently well-adapted population. We have investigated this population by means of 10 microsatellite loci in order to shed light on its genetic structure. Considering thatA. rufais known to crossbreed withA. chukar, the Pianosa Island population was compared at the molecular level with a red-legged partridge breeding stock (Aulla, MS) as well as with a population of pureA. chukar. Our results indicate that the red-legged partridge population from Pianosa, morphologically identified asA. rufa, is actually partly introgressed withA. chukar, questioning its genetic purity and the possible use of this population as a starting stock for future reintroductions elsewhere. [ABSTRACT FROM AUTHOR]

Morocco is one of the regions of the world where many interesting discoveries have recently been made in the field of stygobiology, particularly concerning the cirolanid isopod fauna. One of the most interesting, variable and wide spread of these taxa is the perimediterranean stygobitic genus Typhlocirolana Racovitza, 1905, which has colonized the continental groundwater of Israel, Sicily, Spain, the Balearic Islands, Algeria and Morocco with several species. More populations have recently been found in Morocco, in some southern regions around Agadir, in High Atlas valleys near Marrakech and in the northeastern part of the country close to Oujda. The populations of these zones are not yet described and are the subject of this molecular analysis, together with other already designated species. To investigate the phylogenetic relationships and evolutionary history of the Typhlocirolana populations inhabiting the western Mediterranean basin, we analysed DNA sequences from the mitochondrial 12S and 16S rDNA genes. The molecular data were also used to infer the mechanisms driving the evolution of this thalassoid limnostygobitic cirolanid taxon, considered a good paleogeographic indicator because of its poor dispersion abilities. Vicariance because of paleogeographic events in the western Mediterranean basin played a prime evolutionary role in the Cirolanidae, as already suggested by morphological and ecological studies. Application of a molecular clock provided a time framework of the microevolutionary events occurring in Typhlocirolana populations over the last 40 myr. [ABSTRACT FROM AUTHOR]

This paper redescribes the classical taxon Amerus troisi (Berlese, 1883) on the basis of topotypical material. A new species, Amerus cuspidatus , characterized by short interlamellar setae and a distinct rostral morphology, is also described. In spite of overlapping biogeographical distributions, biochemical analysis indicates that the two Amerus species are clearly differentiated. [ABSTRACT FROM AUTHOR]

Amplitude/frequency characteristics of postural hand tremor in 59 patients with bilateral essential tremor of various degrees of severity were assessed using accelerometric recordings and spectral analysis. Intra-subject comparisons of tremor characteristics between the more and less affected hands were used to control for variability of tremor due to age factors and intersubject differences in amplitude and frequency. Statistical analysis distinguished three different patient groups. Some patients had low amplitude (less than 0.1-0.015 cm) tremor in the less affected limb (which tended to be 7 Hz or more in frequency in the young) and a larger amplitude tremor in the more affected hand which was 1 Hz or more lower in frequency. Other subjects had either bilaterally small or bilaterally large amplitude tremors of similar frequencies. These findings imply that there is a downwards step in frequency between symptomatic tremors of small and large amplitude. The amplitude and frequency of the small amplitude tremors were unrelated but frequency declined with age. The frequency of the large amplitude tremor was generally determined by amplitude but a wide range of amplitudes were compatible with similar frequencies. The frequency of large amplitude tremor also declined with age. It was concluded that there are two types of essential tremor, the smaller amplitude tremor probably derives from an exaggeration of some or all of the mechanisms of normal physiological tremor whereas the larger amplitude tremor probably arises from a separate "pathological" central nervous mechanism. It is not known if or how one may transform into, or be replaced by, the other during progression of the disease. [ABSTRACT FROM AUTHOR]

The supine and erect arterial blood pressure and pulse rate were measured in 13 patients with Parkinson's disease, chronically treated with levodopa and peripheral decarboxilase inhibitors presenting with or without On-Off phenomenon (end-of-dose akinesia). In the patients with dose-related response fluctuations the mean systo-diastolic blood pressure, both supine and erect, was found significantly higher during the Off phase as compared to the On phase and to that of the control group (patients with stable clinical response). The mean diurnal "excursion" of systo-diastolic supine and erect blood pressure in patients with On-Off phenomenon was significantly larger than in the control group. Although the clinical implications of such findings remain to be established, the results of this study indicate that arterial blood pressure fluctuations are a definite autonomic component of end-of-dose akinesia. [ABSTRACT FROM AUTHOR]

Although ex situ conservation programs are increasingly valuable support tools for in situ conservation measures, success depends on these captive individuals to be genetically representative of the recipient population. The Eurasian stone-curlew ( Burhinus oedicnemus ) inhabit steppes that represent some of the most degraded and exploited habitats worldwide. A captive breeding program was implemented in Morocco as a pre-emptive effort for the conservation of the North African subspecies Burhinus oedicnemus saharae . However, the genetic origins of the founders of the captive flock were unknown. We applied a multi-locus approach to characterize the genetic ancestry of the current captive breeding flock by comparing it to wild populations from both Western and Eastern Morocco. Mitochondrial DNA and microsatellite markers were employed to assess levels of genetic diversity and relatedness within each sample, as well as potential genetic differentiation between wild and captive samples through PCA and admixture analyses. We recovered similar genetic diversity estimates, low levels of relatedness, and little differentiation between captive and wild samples. These results confirmed the Moroccan origin of the founders. We provide recommendations for the optimization of the Eurasian Stone Curlew conservation breeding program but also for future conservation breeding programs to ensure the effective conservation of genetic diversity and wild populations.

CD44 is a cell receptor glycoprotein overexpressed in circulating tumor cells (CTCs), with levels linked to an increase in metastatic capacity of several tumors. Hyaluronic acid (HA), the natural ligand of CD44, has primarily been investigated for tumor cell interaction in self-assembled polyelectrolyte multilayer films, with little attention given to the complementary polycation. In this study, we screened sixteen different polyelectrolyte multilayer assemblies of HA and chitosan (CHI) to identify key assembly parameters and surface properties that control and govern CTCs adhesion. Statistics analysis revealed a major role of CHI molecular weight in the adhesion, followed by its combinatorial response either with HA ionization degree or ionic strength. PM-IRRAS analysis demonstrated a correlation between the orientation of HA carboxyl groups on the film surface and CTCs adhesion, directly impacted by CHI molecular weight. Overall, although CTCs binding onto the surface of multilayer films is primarily driven by HA-CD44 interaction, both chitosan properties and film assembly conditions modulate this interaction. These findings illustrate an alternative to modifying the performance of biomaterials with minimal changes in the composition of multilayer films., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)