Contact X-ray microscopy of living cells by using LiF crystal as imaging detector.

In this paper, the use of lithium fluoride (LiF) as imaging radiation detector to analyse living cells by single-shot soft X-ray contact microscopy is presented. High resolved X-ray images on LiF of cyanobacterium Leptolyngbya VRUC135, two unicellular microalgae of the genus Chlamydomonas and mouse macrophage cells (line RAW 264.7) have been obtained utilizing X-ray radiation in the water window energy range from a laser plasma source. The used method is based on loading of the samples, the cell suspension, in a special holder where they are in close contact with a LiF crystal solid-state X-ray imaging detector. After exposure and sample removal, the images stored in LiF by the soft X-ray contact microscopy technique are read by an optical microscope in fluorescence mode. The clear image of the mucilaginous sheath the structure of the filamentous Leptolyngbya and the visible nucleolus in the macrophage cells image, are noteworthiness results. The peculiarities of the used X-ray radiation and of the LiF imaging detector allow obtaining images in absorption contrast revealing the internal structures of the investigated samples at high spatial resolution. Moreover, the wide dynamic range of the LiF imaging detector contributes to obtain high-quality images. In particular, we demonstrate that this peculiar characteristic of LiF detector allows enhancing the contrast and reveal details even when they were obscured by a nonuniform stray light.

Investigating coping and stigma in people living with HIV through narrative medicine in the Italian multicentre non-interventional study DIAMANTE.

Antiretroviral therapy (ART) significantly reduced Human Immunodeficiency Virus (HIV) morbidity and mortality; nevertheless, stigma still characterises the living with this condition. This study explored patients' coping experience by integrating narrative medicine (NM) in a non-interventional clinical trial. From June 2018 to September 2020 the study involved 18 centres across Italy; enrolled patients were both D/C/F/TAF naïve and previously ART-treated. Narratives were collected at enrolment (V1) and last visit (V4) and then independently analysed by three NM specialist researchers through content analysis. One-hundred and fourteen patients completed both V1 and V4 narratives. Supportive relationships with clinicians and undetectable viral load facilitated coping. Conversely, lack of disclosure of HIV-positive status, HIV metaphors, and unwillingness to narrate the life before the diagnosis indicated internalised stigma. This is the first non-interventional study to include narratives as patient reported outcomes (PROs). Improving HIV awareness and reducing the sense of guilt experienced by patients helps to overcome stigma and foster coping.

Involvement of protein kinases and calcium in the NO-signalling cascade for defence-gene induction in ozonated tobacco plants.

This study analyses the signalling pathways triggered by nitric oxide (NO) in response to ozone (O(3)) fumigation of tobacco plants, with particular attention to protein kinase cascades and free cytosolic Ca(2+) in defence-gene activation. NO was visualized with the NO probe DAF-FM. Using a pharmacological approach, the effects of different inhibitors on the expression profiles of NO-dependent defence genes were monitored using RT-PCR. The assay of the kinase activity of the immunoprecipitates complexes shows that O(3) stimulates a 48 kDa salicylic acid (SA)-induced protein kinase (SIPK) in an NO-dependent manner. The O(3)-induced alternative oxidase 1a (AOX1a) and phenylalanine ammonia lyase a (PALa) genes are modulated by phosphorylation by protein kinases, and SIPK might have a role in this up-regulation. By contrast, protein dephosphorylation mediates pathogenesis-related protein 1a (PR1a) expression in O(3)-treated tobacco plants. Ca(2+) is essential, but not sufficient, to promote NO accumulation in ozonated tobacco plants. Intracellular Ca(2+) transients are also essential for PALa up-regulation and cGMP-induced PR1a expression. Partial dependence on intracellular Ca(2+) suggests two different pathways of SA accumulation and PR1a induction. A model summarizing the signalling networks involving NO, SA, and the cellular messengers in this O(3)-induced defence gene activation is proposed.

Mapping the intake of different elements in vegetal tissues by dual-energy X-ray imaging at DaPhine synchrotron light source.

This article reports on the first utilization of the soft X-ray beamline at the DaPhine synchrotron light source for mapping the intake of different elements in plant tissues. As a test, the method of dual-energy X-ray microradiography was applied to the investigation of the natural sulfur content in dried leaf and root samples. Our ultimate goal was to monitor the pollutant lead and its intake, which was added in controlled doses to the hydroponic medium of laboratory-controlled samples of vegetal species. The results obtained by the nondestructive X-ray radiographic analysis are compared to the values of concentrations determined by a standard chemical analysis utilizing atomic absorption spectroscopy. From this comparison the validity of the X-ray detection of heavy metals in biological samples has been confirmed. The superposition of the dual energy results on the simple planar radiography shows the representation of the pollutant intake directly on the sample structures. It should be pointed out that this method, developed here for plant root and leaves could be applied to any biological sample of interest, but the preparation and observation conditions necessitate different strategies according to the type of sample under analysis.

SNOM images of X-ray radiographs at nano-scale stored in a thin layer of lithium fluoride.

In this work, we report a method to observe soft X-ray radiographs at nanoscale of various kind of samples, biological and metallic, stored in a thin layer of lithium fluoride, employing scanning near-field optical microscopy with an optical resolution that reaches 50 nm. Lithium fluoride material works as a novel image detector for X-ray nano-radiographs, due to the fact that extreme ultraviolet radiation and soft X-rays efficiently produce stable point defects emitting optically stimulated visible luminescence in a thin surface layer. The bi-dimensional distribution of the so-created defects depends on the local nanostructure of the investigated sample.

Monitoring of the heavy-metal hyperaccumulation in vegetal tissues by X-ray radiography and by femto-second laser induced breakdown spectroscopy.

This article reports on the utilization of X-ray microradiography and laser induced breakdown spectroscopy (LIBS) techniques for investigation of the metal accumulation in different part of leaf samples. The potential of the LIBS-analysis for finding the proper plant species for phytoremediation is compared with the results of microradiography measurements at the HERCULES source at ENEA, Rome (Italy) and X-ray microradiography experiments at the ELETTRA Synchrotron, Trieste (Italy).

Cyto-histological and morpho-physiological responses of common duckweed (Lemna minor L.) to chromium.

Along with cadmium, lead, mercury and other heavy metals, chromium is an important environmental pollutant, mainly concentrated in areas of intense anthropogenic pressure. The effect of potassium dichromate on Lemna minor populations was tested using the growth inhibition test. Cyto-histological and physiological analyses were also conducted to aid in understanding the strategies used by plants during exposure to chromium. Treatment with potassium dichromate caused a reduction in growth rate and frond size in all treated plants and especially at the highest concentrations. At these concentrations the photosynthetic pathway was also altered as shown by the decrease of maximum quantum yield of photosystem II and the chlorophyll b content and by the chloroplast ultrastructural modifications. Starch storage was also investigated by microscopic observations. It was the highest at the high concentrations of the pollutant. The data suggested a correlation between starch storage and reduced growth; there was greater inhibition of plant growth than inhibition of photosynthesis, resulting in a surplus of carbohydrates that may be stored as starch. The investigation helps to understand the mechanism related to heavy metal tolerance of Lemna minor and supplies information about the behavior of this species widely used as a biomarker.

Chemical modification of human placental glutathione transferase by pyridoxal 5'-phosphate.

Incubation of GST pi from human placenta with 8 mM PLP resulted in a rapid loss of activity during the first 10 min, concomitant with a Schiff base formation. This inactivation was probably due to the formation of a reversible adduct between PLP and the enzyme. After sodium borohydride treatment this adduct was reduced and stabilized. Stoichiometry and peptide isolation studies showed that three lysine residues were modified during reaction of GST and PLP. Protection of the enzyme against inactivation was achieved in the presence of 4 mM GSH suggesting that at least one lysyl residue is associated with the substrate binding site. Peptide mapping by digesting the enzyme with trypsin revealed that lysine shielded by GSH is Lys-127. Our results suggest that this residue may play an important role in enzymatic activity.

Mental disorders and transition to adult mental health services: A scoping review.

BACKGROUND: Data are progressively accumulating regarding the transition to adult services. METHODS: A comprehensive search using the MEDLINE, Embase, PsycINFO, and Cochrane databases up until 16 March 2015 was conducted in order to summarize recent evidence on the transition from child to adult mental health services for patients with mental disorders. Authors extracted data and assessed study quality independently. RESULTS: The main findings of the 33 included studies were discussed taking into consideration four aspects: experiences of patients, carers, and clinicians, accounts of transition, current services models and protocols, and outcomes of transition. Of the 33 studies, 17 focused on a specific mental disorder: seven on attention deficit hyperactivity disorder, four on intellectual disability, three on eating disorders, two on serious emotional disorders and one on autism spectrum disorder. An attempt was also made to integrate the studies' conclusions in order to improve transitional care. CONCLUSIONS: The review reveals an evident need for longitudinal, controlled, health services research to identify and evaluate optimal service models with systematic and seamless transition protocols for patients with mental disorders requiring continuity of care into adult mental services.

Cloning and expression analysis of a Petunia hybrida flower specific mitotic-like cyclin.

A cyclin cDNA clone (Pethy;CycB1;1) was isolated from a Petunia hybrida ovary specific cDNA library. Sequence comparison revealed that Pethy;CYCB1;1 protein is highly homologous to mitotic B1 cyclins. Northern analysis and in situ hybridisation experiments showed that its expression is developmentally regulated and restricted to flower organs. We have attempted to define some of the cell division patterns which contribute to shaping each floral organ by analysing Pethy;CycB1;1 expression on Petunia flower sections. While in sepals, epidermis and parenchyma cell division patterns were comparable, there were two distinct cell division patterns in petals. In the epidermis, Pethy;CYCB1;1 expression was found both at the petal tip and along epidermis, whereas in the parenchyma only at the petal tips. In reproductive organs cell divisions were detected only in sporophytic tissues. No signals were detected inside meiotic cells.

Lithium fluoride as a novel X-ray image detector for biological mu-world capture.

X-ray microradiographs of small biological objects, such as animals and plant materials at micrometric resolution, are currently performed by various methods, all of which are limited by the resolution or the dynamic range of the image detectors. Here a novel X-ray image detector is discussed, in which the previous limitations have been overcome. A film of lithium fluoride salt is used as a detector, in which the stored biological image is read by observing the optically stimulated visible luminescence of the active color centers, efficiently produced by the X-rays.

Microbiological characterization of freatobiont organisms: trial of an analytical protocol and hygienic implications.

The objective of the present study lies in verifing the applicability of an analytical protocol to characterize the microbiology of the surface and gut of freatobiont organisms. The fundamental hypothesis of the study is that the subsurface microinvertebrates represent a protective condition for bacteria, whose presence in potable spring water is rigorously excluded by european standards of quality. The study was conducted between August 1996 and March 1998. Sediment samples were collected from the spring system of "Presciano", whose waters come from the regional aquifer of the Gran Sasso Massif in Italy (L'Aquila, Abruzzo). Drawings of samples were conducted at two different depths (-70 cm and -150 cm). The extration of the fauna (including copepodes) from sediments were achieved with the aid of a Wild M3 microscope. Isolate freatobiont organisms were placed in a sterile Petri plate and subjected to three washings. The liquids of the second and third washings were microbiological analyzed proceeding, in the course of the third washing, to squash the organisms with the aid of a sterile iron handle. Among the microinvertebrates, the copepod Harpacticoida Nitocrella pescei is the most represented species from the two levels of depth. In all, were isolated and identified 106 bacterial species; of these species only 12 (11.3%) did not show any adaptation to the temperature of 35 degrees C. The analytical protocol permitted to make evident a different distribution of microbial species between the two kinds of washing liquids, and this leads to considerate appropriate the adopted protocol. Even if the number of sediment samples analyzed was a few it was identified a great variety of microbial genera and species the greater part of which were mesophilic. This is a consequence of an adaptability that could be favoured by the presence of freatobiont fauna and that concern even microorganisms usually considered "faecal contamination indicators".

Damage and ablation of large bandgap dielectrics induced by a 46.9 nm laser beam.

We applied a 0.3 mJ, 1.7 ns, 46.9 nm soft-x-ray argon laser to ablate the surface of large bandgap dielectrics: CaF2 and LiF crystals. We studied the ablation versus the fluence of the soft-x-ray beam, varying the fluence in the range 0.05-3 J/cm2. Ablation thresholds of 0.06 and 0.1 J/cm2 and ablation depths of 14 and 20 nm were found for CaF2 and LiF, respectively. These results define new ablation conditions for these large bandgap dielectrics that can be of interest for the fine processing of these materials.

[Sociomedical aspects of venous diseases]. / Aspects médico-sociaux des phlébopathies.

Supported by statistical data, the author of this article studies the frequency of phlebological disorders in 1977, and then looks at 1974 in comparison. He draws up the links between phlebopathies and the patients' professions, and studies the geographical distribution of these phlebopathies. Next he questions the current phenomenon of increasing numbers of phlebopathies and the problems which may be raised by hospitalization. After his analysis of these various data he considers the economic aspects of phlebopathy and widens future perspectives within a really sanitary phlebological programme.

Depth of processing and retention of words by alcoholic Korsakoff patients.

The relationship between the depth to which a word is initially processed and its eventual probability of being recognized was investigated with amnesic (alcoholic Korsakoff) patients. Several variations of Craik and Tulving's paradigm designed to asses this relationship were used. basically, this procedure insures analysis of particular features of a word by the nature of the question the subject must answer about the word during its initial presentation. Decision-time measures demonstrated that Korsakoff patients could answer the query nearly as rapidly as normals, but the patients failed to demonstrate a normal increase in recognition as a function of the depth of analysis demanded by the query (Experiments 1--2). However, when the test procedure was extremely simplified (Experiment 3) by presenting only a small number of to-be-recognized words, the Korsakoff patients did demonstrate the normal "pattern" of recognition. It was concluded that under the appropriate circumstances, Korsakoff patients' recognition memory can be improved by instructions to analyze the more sophisticated (semantic) features of verbal information.