322 research outputs found

    Poloxamer 338 affects cell adhesion and biofilm formation in escherichia coli: Potential applications in the management of catheter-associated urinary tract infections

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    Poloxamers are nontoxic, amphiphilic copolymers used in different formulations. Due to its surfactant properties, Poloxamer 338 (P388) is herein proposed as a strategy to avoid biofilm formation often causing recalcitrant catheter-associated urinary tract infections (CAUTI). The aim is to evaluate the ability of P388 coatings to affect the adhesion of Ec5FSL and Ec9FSL Escherichia coli strains on silicone urinary catheters. Attenuated total reflection infrared spectroscopy, atomic force microscopy, and static water contact angle measurement were employed to characterize the P388-coated silicone catheter in terms of amount of P388 layered, coating thickness, homogeneity, and hydrophilicity. In static conditions, the antifouling power of P388 was defined by comparing the E. coli cells adherent on a hydrophilic P388-adsorbed catheter segment with those on an uncoated one. A P388-coated catheter, having a homogeneous coverage of 35 nm in thickness, reduced of 0.83 log10 and 0.51 log10 the biofilm of Ec5FSL and Ec9FSL, respectively. In dynamic conditions, the percentage of cell adhesion on P388-adsorbed silicone channels was investigated by a microfluidic system, simulating the in vivo conditions of catheterized patients. As a result, both E. coli isolates were undetected. The strong and stable antifouling property against E. coli biofilm lead us to consider P388 as a promising anti-biofilm agent for CAUTIs control

    Mitochondrial myopathy and comorbid major depressive disorder. effectiveness of dTMS on gait and mood symptoms

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    Background: Mitochondrial myopathies (MMs) often present with leukoencephalopathy and psychiatric symptoms, which do not respond to or worsen with psychiatric drugs. Case report: A 67-year-old woman with a 10-year history of probable chronic progressive external ophthalmoplegia, an MM, had drug-resistant, anxious-depressive symptoms. Since she had never had seizures, we proposed 20 sessions of deep transcranial magnetic stimulation (dTMS) for her depression. Surprisingly, besides the expected improvement of depression, we observed marked improvement of movement disorder that lasted as long as the patient was undergoing dTMS. She also improved her performance on neuropsychological tests of executive function and cognitive speed. Depressive symptom improvement was persistent, while anxiety symptoms recurred after the end of the sessions. Conclusions: dTMSmay be an alternative antidepressant strategy in patients withMMs, provided that they are free from seizures. The mechanism of improvement of motor disturbance may relate to dorsolateral prefrontal cortex stimulation and improved executive function and needs further investigation

    Carbon allocation and carbon isotope fluxes in the plant-soil-atmosphere continuum: a review

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    The terrestrial carbon (C) cycle has received increasing interest over the past few decades, however, there is still a lack of understanding of the fate of newly assimilated C allocated within plants and to the soil, stored within ecosystems and lost to the atmosphere. Stable carbon isotope studies can give novel insights into these issues. In this review we provide an overview of an emerging picture of plant-soil-atmosphere C fluxes, as based on C isotope studies, and identify processes determining related C isotope signatures. The first part of the review focuses on isotopic fractionation processes within plants during and after photosynthesis. The second major part elaborates on plant-internal and plant-rhizosphere C allocation patterns at different time scales (diel, seasonal, interannual), including the speed of C transfer and time lags in the coupling of assimilation and respiration, as well as the magnitude and controls of plant-soil C allocation and respiratory fluxes. Plant responses to changing environmental conditions, the functional relationship between the physiological and phenological status of plants and C transfer, and interactions between C, water and nutrient dynamics are discussed. The role of the C counterflow from the rhizosphere to the aboveground parts of the plants, e.g. via CO<sub>2</sub> dissolved in the xylem water or as xylem-transported sugars, is highlighted. The third part is centered around belowground C turnover, focusing especially on above- and belowground litter inputs, soil organic matter formation and turnover, production and loss of dissolved organic C, soil respiration and CO<sub>2</sub> fixation by soil microbes. Furthermore, plant controls on microbial communities and activity via exudates and litter production as well as microbial community effects on C mineralization are reviewed. A further part of the paper is dedicated to physical interactions between soil CO<sub>2</sub> and the soil matrix, such as CO<sub>2</sub> diffusion and dissolution processes within the soil profile. Finally, we highlight state-of-the-art stable isotope methodologies and their latest developments. From the presented evidence we conclude that there exists a tight coupling of physical, chemical and biological processes involved in C cycling and C isotope fluxes in the plant-soil-atmosphere system. Generally, research using information from C isotopes allows an integrated view of the different processes involved. However, complex interactions among the range of processes complicate or currently impede the interpretation of isotopic signals in CO<sub>2</sub> or organic compounds at the plant and ecosystem level. This review tries to identify present knowledge gaps in correctly interpreting carbon stable isotope signals in the plant-soil-atmosphere system and how future research approaches could contribute to closing these gaps

    Bioactivators as a potential strategy for dredged marine sediment recovery

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    Sediment dredging from harbors and water bodies in order to maintain the navigation is a necessity worldwide; however, the storage and treatment of sediments is a problem for harbor managers. Sediment decontamination could represent a sustainable approach for turning them into a new source of environmentally reusable material. To manage the sediments dredged from the Livorno harbour, several possible recycling techniques are being explored, including sediment washing and bioremediation. A combination of these two techniques can also be taken into consideration. This study examines the feasibility of an enzyme enhanced bioremediation technology used as it is, or in combination with the sediment washing. Specifically, we applied an enhanced bioremediation approach to both raw sediments and two derivate granulometric fractions separated by a pilot sediment washing facility: a silt-clay fraction (63 \u3bcm<200 \u3bcm). The preliminary sediment washing was effective in concentrating the organic and inorganic contamination into a smaller volume of fine sediment particles (silt-clay). The bioremediation experiment, carried out in triplicate at mesoscale level, consisted in setting up containers of about 0.2 m3 each, filled with the three matrices (raw sediment, clay-silt and sand fractions) treated and untreated (control) with bioactivators (a mixture of microorganisms, enzymes and synergists). The physical, chemical and biological properties of sediments were determined at the initial sampling time (t0) and after three months (t90) from the beginning of the experimentation. The bioactivator application, providing specialized microorganisms and stimulating the growth of indigenous microorganisms, determined the increase in microbial respiration and in hydrolytic enzyme activities in all the treated matrices, in particular in the siltclay fraction. However, this fraction both treated and untreated, has not been able to degrade significant amount of organic pollutants. This is probably due to the burial of contaminats in micropores making them inaccessible to microorganisms and extracellular enzymes. On the contrary, a significant reduction in total petroleum hydrocarbon was observed in sand and raw sediment matrices after three months from remediation strategy application (about 50%), indicating the efficiency of the bioremediation technology

    Species-specific adaptations explain resilience of herbaceous understorey to increased precipitation variability in a Mediterranean oak woodland

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    To date, the implications of the predicted greater intra-annual variability and extremes in precipitation on ecosystem functioning have received little attention. This study presents results on leaf-level physiological responses of five species covering the functional groups grasses, forbs, and legumes in the understorey of a Mediterranean oak woodland, with increasing precipitation variability, without altering total annual precipitation inputs. Although extending the dry period between precipitation events from 3 to 6 weeks led to increased soil moisture deficit, overall treatment effects on photosynthetic performance were not observed in the studied species. This resilience to prolonged water stress was explained by different physiological and morphological strategies to withstand periods below the wilting point, that is, isohydric behavior in Agrostis, Rumex, and Tuberaria, leaf succulence in Rumex, and taproots in Tolpis. In addition, quick recovery upon irrigation events and species-specific adaptations of water-use efficiency with longer dry periods and larger precipitation events contributed to the observed resilience in productivity of the annual plant community. Although none of the species exhibited a change in cover with increasing precipitation variability, leaf physiology of the legume Ornithopus exhibited signs of sensitivity to moisture deficit, which may have implications for the agricultural practice of seeding legume-rich mixtures in Mediterranean grassland-type systems. This highlights the need for long-term precipitation manipulation experiments to capture possible directional changes in species composition and seed bank development, which can subsequently affect ecosystem state and functioninginfo:eu-repo/semantics/publishedVersio

    PON1 polymorphisms can predict generalized anxiety and depressed mood in patients with multiple chemical sensitivity

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    Background: Multiple chemical sensitivity (MCS) is a chronic condition with somatic, cognitive and affective symptoms that follow contact with chemical agents at usually non toxic concentrations. We aimed to assess the role of genetic polymorphisms involved in oxidative stress on anxiety and depression in MCS. Materials &amp; methods: Our study investigated the CAT rs1001179, MPO rs2333227, PON1 rs662 and PON1 rs705379 polymorphisms in MCS. Results: The AG genotype of the PON1 rs662 and the TT and CT genotypes of the PON1 rs705379 were involved in anxiety and depression. Discussion: These results are in line with existing evidence of PON1 involvement in MCS and suggest a further role of this gene in the exhibition of anxiety and depression in this disease

    Does long-term warming affect C and N allocation in a Mediterranean shrubland ecosystem? Evidence from a<sup>13</sup>C and<sup>15</sup>N labeling field study

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    © 2017 In the Mediterranean basin the effects of climate warming on ecosystem functioning will strongly depend on the warming intensity directly but also on its effects on evapotranspiration and nutrient cycling. Climate manipulation experiments under field conditions are a source of unique empirical evidence regarding climate-related modifications of biotic processes. A field night-time warming experiment, simulating the predicted near-future increase in ambient temperatures (+0.3 up to 1 °C), was established in a Mediterranean shrub community located in Porto Conte (Italy) in 2001. After 11 years of continuous treatment, we labeled the dominant shrub Cistus monspeliensis with 13 CO 2 and studied the dynamics of the label allocation between aboveground and belowground pools and fluxes in warmed and ambient plots within 2 weeks of the chasing period. The interactions between C and N metabolism were assessed by parallel labeling of soil with K 15 NO 3. Most of the assimilated 13 C was respired by Cistus shoots (28–51%) within two weeks. Cistus under warming respired more 13 C label and tended to allocate less 13 C to leaves, branches and roots. The higher C and N content in microbial biomass in warming plots, combined with the higher N content in plant tissues and soil, evidenced a greater N mobilization in soil and a better nutrient status of the plants as compared to the ambient treatment. Acceleration of N cycling is probably responsible for higher respiratory C losses, but combined with the reduction in the number of frost days, should also positively affect plant photosynthetic performance. We conclude that, although Cistus plants are already growing in conditions close to their thermal optimum, long-term warming will positively affect the performance of this species, mainly by reducing the nutrient constraints. This positive effect will highly depend on the frequency and amount of rain events and their interactions with soil N content

    International Expert Opinions and Recommendations on the Use of Melatonin in the Treatment of Insomnia and Circadian Sleep Disturbances in Adult Neuropsychiatric Disorders

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    Introduction: Insomnia and circadian rhythm disorders, such as the delayed sleep phase syndrome, are frequent in psychiatric disorders and their evaluation and management in early stages should be a priority. The aim of this paper was to express recommendations on the use of exogenous melatonin, which exhibits both chronobiotic and sleep-promoting actions, for the treatment of these sleep disturbances in psychiatric disorders. Methods: To this aim, we conducted a systematic review according to PRISMA on the use of melatonin for the treatment of insomnia and circadian sleep disorders in neuropsychiatry. We expressed recommendations for the use of melatonin in psychiatric clinical practice for each disorder using the RAND/UCLA appropriateness method. Results: We selected 41 studies, which included mood disorders, schizophrenia, substance use disorders, attention deficit hyperactivity disorders, autism spectrum disorders, neurocognitive disorders, and delirium; no studies were found for both anxiety and eating disorders. Conclusion: The administration of prolonged release melatonin at 2–10 mg, 1–2 h before bedtime, might be used in the treatment of insomnia symptoms or comorbid insomnia in mood disorders, schizophrenia, in adults with autism spectrum disorders, neurocognitive disorders and during sedative-hypnotics discontinuation. Immediate release melatonin at &lt;1 mg might be useful in the treatment of circadian sleep disturbances of neuropsychiatric disorders

    Familial aggregation of MATRICS Consensus Cognitive Battery scores in a large sample of outpatients with schizophrenia and their unaffected relatives

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    The increased use of the MATRICS Consensus Cognitive Battery (MCCB) to investigate cognitive dysfunctions in schizophrenia fostered interest in its sensitivity in the context of family studies. As various measures of the same cognitive domains may have different power to distinguish between unaffected relatives of patients and controls, the relative sensitivity of MCCB tests for relative-control differences has to be established. We compared MCCB scores of 852 outpatients with schizophrenia (SCZ) with those of 342 unaffected relatives (REL) and a normative Italian sample of 774 healthy subjects (HCS). We examined familial aggregation of cognitive impairment by investigating within-family prediction of MCCB scores based on probands' scores
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