Nanostructured Mg–10Al nanocomposites reinforced by diamondoids were processed via cryomilling and spark plasma sintering. The effect of 1wt% of diamantane on the microstructure of the nanostructured ...Mg–10Al nanocomposites was studied using scanning and transmission electron microscopies, electron dispersive spectroscopy and X-ray diffraction. A detailed microstructural examination revealed that diamondoids mainly located within the Mg-matrix induce a lattice strain along the c-direction and a potential effect on the γ-Al12Mg17 precipitation. The mechanical behavior of the nanostructured Mg-based nanocomposites was investigated by micro- and macro-compression tests along with in-situ SEM nanoindentation experiments at room temperature. The compressive strength, elastic modulus and hardness of the nanocomposites were found to be significantly improved as compared with the mechanical behavior of diamondoids-free nanostructured Mg–10Al alloys. Since no change in the grain size has been found after adding diamantane, we attribute the enhanced mechanical behavior of the nanocomposites to a combined effect of precipitation hardening and the microscopic residual stress generated by diamantane–Mg matrix mismatch. Our results provide new insights into the mechanisms involved in the development of high-performance Mg-nanocomposites.
Summary
Background
Prebiotics have been shown to reduce abdominal symptoms in patients with functional gut disorders, despite that they are fermented by colonic bacteria and may induce gas‐related ...symptoms.
Aim
To investigate changes in the metabolic activity of gut microbiota induced by a recognised prebiotic.
Methods
Healthy subjects (n = 20) were given a prebiotic (2.8 g/day HOST‐G904, HOST Therabiomics, Jersey, Channel Islands) for 3 weeks. During 3‐day periods immediately before, at the beginning and at the end of the administration subjects were put on a standard diet (low fibre diet supplemented with one portion of high fibre foods) and the following outcomes were measured: (i) number of daytime gas evacuations for 2 days by means of an event marker; (ii) volume of gas evacuated via a rectal tube during 4 h after a test meal; and (iii) microbiota composition by faecal Illumina MiSeq sequencing.
Results
At the beginning of administration, HOST‐G904 significantly increased the number of daily anal gas evacuations (18 ± 2 vs. 12 ± 1 pre‐administration; P < 0.001) and the volume of gas evacuated after the test meal (236 ± 23 mL vs. 160 ± 17 mL pre‐administration; P = 0.006). However, after 3 weeks of administration, these effects diminished (11 ± 2 daily evacuations, 169 ± 23 mL gas evacuation). At day 21, relative abundance of butyrate producers (Lachnospiraceae) correlated inversely with the volume of gas evacuated (r = −0.52; P = 0.02).
Conclusion
The availability of substrates induces an adaptation of the colonic microbiota activity in bacterial metabolism, which produces less gas and associated issues. Clinical trials.gov NCT02618239.
Linked ContentThis article is linked to Staudacher paper. To view this article visit https://doi.org/10.1111/apt.13976.
Accessible summary
What is known on the subject?
Paediatric sleep problems are clinical conditions that often coexist with other mental health problems and meet criteria that warrant the ...implementation of screening procedures, including high prevalence, and significant clinical impact.
Researchers have designed the BEARS, a user‐friendly paediatric sleep screening tool that seems to increase the amount of sleep information recorded, as well as the likelihood of identifying sleep problems during routine health encounters. Nonetheless, there are no studies using the BEARS in Spanish‐speaking samples.
What this paper adds to existing knowledge?
Using a sample of children with mental health problems, this study provides support for the use of the Spanish version of the BEARS to identify the most common sleep problems seen in paediatric populations.
What are the implications for practice?
Considering how frequent sleep problems are, it is especially important for health professionals working with children in general, and with children with mental health problems in particular, to be aware of and be encouraged to use simple brief screening tools for paediatric sleep problems.
Objective
Research studies describe a high prevalence of sleep problems in children with mental health problems, up to 50%, and its role as a risk factor in the development of psychopathology. These often go unnoticed and are not evaluated in the clinical field. Our objective was to assess the concurrent validity of the BEARS, a brief paediatric sleep screening instrument, using the Children Sleep Habits Questionnaire (CSHQ) as the comparison instrument.
Methods
In this cross‐sectional descriptive study, the BEARS was applied by a registered nurse to a sample of parents of children aged 2–16 years (n = 60, 71.7% male) who attended a mental healthcare facility (located in Murcia, Spain) for the first time to receive a group psychoeducational intervention. The association between the information collected with the BEARS and scores on the related subscales of the CSHQ was assessed by Mann–Whitney U tests.
Results
Children who, according to the BEARS, had a sleep problem obtained scores on the CSHQ‐related subscales significantly higher than children who did not have a sleep problem (all Ps < 0.05).
Conclusion
Our results support the concurrent validity of the Spanish translation of the BEARS to detect sleep problems in paediatric nursing assessments. Further studies, with bigger and more heterogeneous samples, are warranted.
Lysophosphatidic acid (LPA) is a phospholipid growth factor involved in cell proliferation, differentiation, migration, inflammation, angiogenesis, wound healing, cancer invasion, and survival. This ...study was directed to evaluate the immunoexpression of LPA-1, cell proliferation, apoptosis, and angiogenesis markers in preneoplastic lesions induced with cadmium chloride in rat prostate.
The following parameters were calculated in ventral prostate of normal rats and rats that received Cd in drinking water during 24 months: percentages of cells immunoreactive to LPA-1 (LILPA1), PCNA (LIPCNA), MCM7 (LIMCM7), ubiquitin (LIUBI), apoptotic cells (LIAPO), and p53 (LIp53); volume fraction of Bcl-2 (VFBcl-2); and length of microvessels per unit of volume (LVMV/mm3). Data were analyzed using Student's t-test and Pearson correlation test.
The LILPA1 in dysplastic lesions and normal epithelium of Cd-treated rats was significantly higher than those in the control group. Markers of proliferation were significantly increased in dysplastic lesions, whereas some apoptotic markers were significantly decreased. No significant differences between groups were found in VFBcl-2. Dysplastic lesions showed a significant increase of LIp53. The length of microvessels per unit of volume was elevated in dysplastic acini. Statistically significant correlations were found only between LILPA1 and LIUBI.
Our results suggest that LPA-1 might be implicated in dysplastic lesions induced by cadmium chloride development. More studies are needed to confirm its potential contribution to the disease.
Serrated flow, also known as the Portevin-Le Chatelier effect, has been extensively investigated in binary Mg-alloys such as Mg-Ag, Mg-Y and Mg-Li alloys. Interestingly, however, this effect has not ...been observed in Mg-Al alloys. In this work, we report the appearance of serrations in nanostructured Mg-Al alloys processed by cryomilling and spark-plasma-sintering during in-situ SEM microcompression tests at room temperature and strain rates between 2×10−3 and 10−1s−1. The observed serrated stress-strain behavior is attributed to the dynamic strain aging by which interstitial O and/or N impurities introduced during cryomilling diffuse and interact with in-grown dislocations during deformation.
(a) Engineering and true stress-strain curves at 2×10−2 s−1 of strain rate. Inset is a SEM image of a Mg-10Al micropillar after microcompression under strain rate of 2×10−2 s−1. (b) Zoom in the periodic region enclosed by a rectangle in (a) showing type B serrations. Display omitted
In the present study, the chemical composition of the microalga
was investigated. The extraction of bioactive compounds was done using pressurized liquid extraction (PLE) at different temperatures ...(40-180 °C) and using green solvents (ethanol-water mixtures). A statistical design of experiments was used to optimize the maximum antioxidant capacity of the extracts by response surface methodology. The antioxidant capacity was determined through the inhibition of 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, while the chemical analyses of the extracts were carried out using different chromatographic techniques. Chlorophylls and carotenoids were analyzed by high-performance liquid chromatography coupled to a diode array detector and mass spectrometry (HPLC-DAD-MS/MS) and carbohydrates by gas chromatography with flame ionization detection (GC-FID) and high-pressure size-exclusion chromatography coupled to an evaporative light-scattering detector (HPSEC-ELSD). The results showed different possibilities for the extraction conditions, depending on the desired bioactivity or chemical composition. Briefly, (i) mixtures of ethanol-water containing around 40% ethanol at 180 °C gave the best antioxidant capacity, (ii) mixtures containing around 50% ethanol at 110 °C gave the best yield of β-glucan paramylon, and (iii) the use of pure ethanol at a low temperature (40 °C) is the best choice for the recovery of carotenoids such as diatoxanthin. Summing up,
seems to be a good candidate to be used in biorefinery to obtain different bioactive compounds.
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•The exceptional hardness of Ti-based materials, 40% plus above the hardness of the base alloy, was achieved without compromise to low specific weight of the material.•The addition of ...TiC to the alloy Ti-6Al-4 V in an amount of 40% leads to the formation of a discontinuous composite and an increase in the hardness of the material; with a higher particle content, the composite becomes continuous, exhibiting very fragile behavior.•TiC chemically reacts with the matrix alloy and forms a strong interfacial bond with the base alloy.•As a result of high temperature aging of the composite, the hard phases of Ti2C and Ti3AlC formed in the expense of a relatively soft matrix alloy and further contribute to a significant increase in hardness.
Titanium alloy composites, reinforced with a light second phase and made using inexpensive powder metallurgy, attract considerable attention due to the directness of their intentional hardness increase without compromising low weight of materials. In this study the metal-matrix composites (MMC) of Ti-6Al-4V alloy reinforced with light and hard particles of TiC (up to 80%, vol.) were made using blended elemental powder metallurgy of hydrogenated titanium. Post-sintering solution treatment for 45 min. at 880 °C and 1000 °C and water quenching followed by the 5 hrs. aging at 550 °C was used to additionally refine the microstructure and properties of MMC. For the duration of thermal exposure throughout solution treatment and additional aging the matrix and reinforcement phase underwent distinct structural changes that modified the mechanical properties of materials. It has been shown that the used reinforcement presents an exceptional opportunity for hardening of Ti-based composites without compromising their low specific weigh. It can increase the hardness of material by more than 40% due to the ability of TiC to chemically react with the matrix to form a strong interfacial bond and its ability to form hard compounds of Ti2C and Ti3AlC in the expense of the relatively soft matrix alloy.
We report the microstructural characterization and compressive behavior of nanostructured Mg–10Al alloys processed via cryomilling, spark plasma sintering and extrusion. We demonstrate that warm ...extrusion leads to ~40% improvement in compressive strength of nanostructured Mg–10Al alloys. A yield strength of 550MPa, and an ultimate strength of 580MPa are measured. The improvement in strength is mainly attributed to the occurrence of precipitation hardening by γ-Al12Mg17 nanoprecipitates and basal-texture strengthening in addition to the grain size strengthening mechanism. Our results suggest a successful approach for the design of high strength nanostructured Mg–Al alloys.
Legionella spp. is the causative agent of Legionnaires' disease and is transmitted through aerosols emanating from man-made water systems. Legionella resistance to water treatments has been related ...to its association with environmental amoebae such as Acanthamoeba. Due to the high presence of this protozoon in Spain and the high rate of notification of Legionnaires' disease of this country, the aims of this work were to study the coexistence of these bacteria and protozoa in water as well as their interaction. The usefulness of Acanthamoeba co-culture for the isolation of environmental Legionella was also studied. For this purpose, 70 water samples were collected in 2011 from three Drinking Water Treatment Plants, three Wastewater Treatment Plants and five Natural Pools in Spain. Acanthamoeba was found by PCR in 87.1% (61/70) samples and, by culture in 85.7% (60/70) samples. Legionella was detected by PCR in 58.6% (41/70) of water samples, in 5.7% (4/70) by agar culture and 75.7% (53/70) by Acanthamoeba co-culture. From the 54 Acanthamoeba water isolates, Legionella was detected in 43 of them independently of Acanthamoeba's genotype (T3, T4 and T11). Legionella feeleii, Legionella birminghamiensis, Legionella gresilensis/berliardensis, Legionella fairfieldensis, Legionella drozanski and Legionella falloni were identified. In conclusion, our results showed that environmental Acanthamoeba is infected by Legionella to a high percentage, and due to its ubiquity, high resistance and its pathogenic potential per se, new methods for its elimination should be studied. Also, the high effectivity of Acanthamoeba co-culture for Legionella detection has been shown.
•Acanthamoeba is infected by Legionella in environmental water samples.•Legionella feeleii is a frequent pathogenic microorganism in our environment.•Legionella culture in Acanthamoeba increased the sensibility in Legionella detection.
Advanced prostate cancer cells preferentially metastasize to bone by acquiring a bone phenotype that allows metastatic cells to thrive in the skeletal environment. Identification of factors that ...promote the expression of ectopic bone genes-process known as osteomimicry-leading to tumor progression is crucial to prevent and treat metastatic prostate cancer and prolong life expectancy for patients. Here, we identify the extracelular matrix protein mindin in the secretome of prostate adenocarcinoma cells and show that mindin overexpression in human and mouse TRAMP-C1-induced prostate tumors correlates with upregulated levels of bone-related genes in the tumorigenic prostate tissues. Moreover, mindin silencing decreased osteomimicry in adenocarcinoma cells and in the prostate tumor mice model, as well as reduced tumor cell proliferation, migration and adhesion to bone cells. Inhibition of the extracellular signal-regulated kinase 1/2 (ERK 1/2) phosphorylation decreased the proliferative, migratory and pro-adhesion actions of mindin on prostate tumor cells. In addition, conditioned media obtained by crosstalk stimulation of either osteocytes or osteoblasts with the secretome of TRAMP-C1 cells promoted osteomimicry in prostate tumor cells; an effect inhibited by mindin silencing of TRAMP-C1 cells. In vivo, tibiae of primary tumor-bearing mice overexpressed the pro-angiogenic and pro-metastattic factor vascular endothelial growth factor receptor 2 (VEGFR2) in a mindin-dependent manner. Our findings indicate that mindin is a novel regulator of osteomimicry in prostate tumors and potentially mediates tumor-bone cell crosstalk, suggesting its promising role as a target to inhibit bone metastases.
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