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371.
Insulation of samples and water sorption coefficient of cement mortars modified with polypropylene fibres. In the following paper are shown results of water capillary suction in cement mortars prepared in accordance with 18 different recipes. All the mortars were prepared using natural quartz sand 0 to 2 mm. The mortars were varied with the use of two different cements and two different water‐cement ratios w/c, namely clean cement CEM I 42.5 R at w/c = 0.55 and ash cement CEM II/B‐V 32.5 R at w/c = 0.55 and w/c = 0.45. These mortars were modified by adding three types of polypropylene fibres with five lengths ranging from 3 to 38 mm. All samples were insulated against humidity on the side surfaces to ensure the one‐way water flow during the execution of this experiment. In relation to each type of mortar two different types of insulation were used: a silicone coat and polyethylene foil. The comparative analysis received served to evaluate the scale of reaction to the sorption coefficient A of such factors as: the type of cement, the w/c ratio, the type and length of fibres and the type of humidity insulation. It appeared that this last factor exerted a major effect on the course of the process, and equally on the A parameter when described in terms of quantity. 相似文献
372.
Agata Dorotkiewicz-Jach Pawel Markwitz Zuzanna Drulis-Kawa 《International journal of molecular sciences》2021,22(18)
In this study, we investigated the anti-pseudomonal activity of cupric ions (Cu2+), strawberry furanone (HDMF), gentamicin (GE), and three lytic Pseudomonas aeruginosa bacteriophages (KT28, KTN4, LUZ19), separately and in combination. HDMF showed an anti-virulent effect but only when applied with Cu2+ or GE. GE, at a sub-minimal inhibitory concentration, slowed down phage progeny production due to protein synthesis inhibition. Cu2+ significantly reduced both the bacterial cell count and the number of infective phage particles, likely due to its genotoxicity or protein inactivation and cell membrane disruption effects. Furthermore, Cu2+‘s probable sequestration by phage particles led to the reduction of free toxic metal ions available in the solution. An additive antibacterial effect was only observed for the combination of GE and Cu2+, potentially due to enhanced ROS production or to outer membrane permeabilization. This study indicates that possible interference between antibacterial agents needs to be carefully investigated for the preparation of effective therapeutic cocktails. 相似文献
373.
Valentina La Cognata Maria Guarnaccia Giovanna Morello Martino Ruggieri Agata Polizzi Sebastiano Cavallaro 《International journal of molecular sciences》2021,22(18)
Lysosomal storage diseases (LSDs) are a heterogeneous group of approximately 70 monogenic metabolic disorders whose diagnosis represents an arduous challenge for clinicians due to their variability in phenotype penetrance, clinical manifestations, and high allelic heterogeneity. In recent years, the approval of disease-specific therapies and the rapid emergence of novel rapid diagnostic methods has opened, for a set of selected LSDs, the possibility for inclusion in extensive national newborn screening (NBS) programs. Herein, we evaluated the clinical utility and diagnostic validity of a targeted next-generation sequencing (tNGS) panel (called NBS_LSDs), designed ad hoc to scan the coding regions of six genes (GBA, GAA, SMPD1, IDUA1, GLA, GALC) relevant for a group of LSDs candidate for inclusion in national NBS programs (MPSI, Pompe, Fabry, Krabbe, Niemann Pick A-B and Gaucher diseases). A standard group of 15 samples with previously known genetic mutations was used to test and validate the entire flowchart. Analytical accuracy, sensitivity, and specificity, as well as turnaround time and costs, were assessed. Results showed that the Ion AmpliSeq and Ion Chef System-based high-throughput NBS_LSDs tNGS panel is a fast, accurate, and cost-effective process. The introduction of this technology into routine NBS procedures as a second-tier test along with primary biochemical assays will allow facilitating the identification and management of selected LSDs and reducing diagnostic delay. 相似文献
374.
Grzegorz A. Czapski Lidia Babiec Henryk Jko Magdalena Gssowska-Dobrowolska Magdalena Cielik Marta Matuszewska Magorzata Frontczak-Baniewicz Karolina Zajdel Agata Adamczyk 《International journal of molecular sciences》2021,22(18)
Tuberous sclerosis complex (TSC) is a rare, multi-system genetic disease with serious neurological and mental symptoms, including autism. Mutations in the TSC1/TSC2 genes lead to the overactivation of mTOR signalling, which is also linked to nonsyndromic autism. Our aim was to analyse synaptic pathology in a transgenic model of TSC: two-month-old male B6;129S4-Tsc2tm1Djk/J mice with Tsc2 haploinsufficiency. Significant brain-region-dependent alterations in the expression of several synaptic proteins were identified. The most prominent changes were observed in the immunoreactivity of presynaptic VAMP1/2 (ca. 50% increase) and phospho-synapsin-1 (Ser62/67) (ca. 80% increase). Transmission electron microscopy demonstrated serious ultrastructural abnormalities in synapses such as a blurred structure of synaptic density and a significantly increased number of synaptic vesicles. The impairment of synaptic mitochondrial ultrastructure was represented by excessive elongation, swelling, and blurred crista contours. Polyribosomes in the cytoplasm and swollen Golgi apparatus suggest possible impairment of protein metabolism. Moreover, the delamination of myelin and the presence of vacuolar structures in the cell nucleus were observed. We also report that Tsc2+/− mice displayed increased brain weights and sizes. The behavioural analysis demonstrated the impairment of memory function, as established in the novel object recognition test. To summarise, our data indicate serious synaptic impairment in the brains of male Tsc2+/− mice. 相似文献
375.
Agata Y. Motomochi K. Fukushima Y. Shirahama M. Kurumada M. Kuroda N. Sadakata H. Hayashi K. Yamada T. Takahashi K. Fujita T. 《Solid-State Circuits, IEEE Journal of》2000,35(11):1668-1672
A novel fast random cycle embedded RAM macro with dual-port interleaved DRAM architecture (D2RAM) has been developed. The macro exploits three key circuit techniques: dual-port interleaved DRAM architecture, two-stage pipelined circuit operation, and write before sensing. Random cycle time of 8 ns under worst-case conditions has been confirmed with a 0.25-μm embedded DRAM test chip. This is six times faster than conventional DRAM 相似文献
376.
Agata Zuccaro Begoa Zapatería María Gracia Snchez-Alonso María Haro María Limones Gloria Terrados Adriana Izquierdo Patricia Corrales Gema Medina-Gmez Gonzalo Herradn Julio Sevillano María del Pilar Ramos-lvarez 《International journal of molecular sciences》2021,22(17)
(1) Background: Pleiotrophin preserves insulin sensitivity, regulates adipose tissue lipid turnover and plasticity, energy metabolism and thermogenesis. The aim of this study was to determine the role of pleiotrophin in hepatic lipid metabolism and in the metabolic crosstalk between the liver and brown and white adipose tissue (AT) in a high-fat diet-induced (HFD) obesity mice model. (2) Methods: We analyzed circulating variables, lipid metabolism (hepatic lipid content and mRNA expression), brown AT thermogenesis (UCP-1 expression) and periovarian AT browning (brown adipocyte markers mRNA and immunodetection) in Ptn−/− mice either fed with standard-chow diet or with HFD and in their corresponding Ptn+/+ counterparts. (3) Results: HFD-Ptn−/− mice are protected against the development of HFD-induced insulin resistance, had lower liver lipid content and lower expression of the key enzymes involved in triacylglycerides and fatty acid synthesis in liver. HFD-Ptn−/− mice showed higher UCP-1 expression in brown AT. Moreover, Ptn deletion increased the expression of specific markers of brown/beige adipocytes and was associated with the immunodetection of UCP-1 enriched multilocular adipocytes in periovarian AT. (4) Conclusions: Ptn deletion protects against the development of HFD-induced insulin resistance and liver steatosis, by increasing UCP-1 expression in brown AT and promoting periovarian AT browning. 相似文献
377.
We measured in vitro interferon-gamma, interleukin-4 and IgE production of peripheral blood mononuclear cells stimulated with ovalbumin. Interferon-gamma in culture supernatants of ovalbumin-stimulated peripheral blood mononuclear cells from hen's egg- sensitive patients with atopic dermatitis was significantly higher than that of healthy children or hen's egg-sensitive patients with immediate symptoms. Furthermore, in patients with atopic dermatitis who were sensitive to hen's egg and patients with immediate symptoms, there was an inverse relationship between interferon-gamma and IgE production (r = -0.535, p <0.05), and significant correlation was found between interleukin-4 and IgE production (r = 0.802, p <0.05). For the above reasons, IgE synthesis of ovalbumin-stimulated peripheral blood mononuclear cells may be suppressed by interferon-gamma in patients with atopic dermatitis. In contrast, in patients with immediate symptoms, interleukin-4 may play a major role in the pathogenesis of increased IgE production. 相似文献
378.
Katarzyna Tonecka Agata Braniewska Zofia Pilch Zuzanna Sas Marcin Skorzynski Elisabetta Manuali Tomasz P. Rygiel 《International journal of molecular sciences》2021,22(10)
Inflammatory bowel disease is characterized by the infiltration of immune cells and chronic inflammation. The immune inhibitory receptor, CD200R, is involved in the downregulation of the activation of immune cells to prevent excessive inflammation. We aimed to define the role of CD200R ligand-CD200 in the experimental model of intestinal inflammation in conventionally-reared mice. Mice were given a dextran sodium sulfate solution in drinking water. Bodyweight loss was monitored daily and the disease activity index was calculated, and a histological evaluation of the colon was performed. TNF-α production was measured in the culture of small fragments of the distal colon or bone marrow-derived macrophages (BMDMs) cocultured with CD200+ cells. We found that Cd200−/− mice displayed diminished severity of colitis when compared to WT mice. Inflammation significantly diminished CD200 expression in WT mice, particularly on vascular endothelial cells and immune cells. The co-culture of BMDMs with CD200+ cells inhibited TNF-α secretion. In vivo, acute colitis induced by DSS significantly increased TNF-α secretion in colon tissue in comparison to untreated controls. However, Cd200−/− mice secreted a similar level of TNF-α to WT mice in vivo. CD200 regulates the severity of DSS-induced colitis in conventionally-reared mice. The presence of CD200+ cells decreases TNF-α production by macrophages in vitro. However, during DDS-induced intestinal inflammation secretion of TNF-α is independent of CD200 expression. 相似文献
379.
380.
Polyamide thin-film composite (PA-TFC) membranes make large-scale desalination effective. Interfacial polymerization (IP) is used to make PA-TFC membranes, but it may limit the range of monomers that can be used, which hinders progress toward advanced membranes. Layer-by-layer (LbL) sequential deposition could circumvent kinetic and thermodynamic limitations of the conventional IP process to facilitate incorporation of different co-monomers into the membrane. The selective layer needs to be deposited onto a microporous support, but depositing LbL coatings on microporous supports often results in defective membranes. Using a poly(vinyl alcohol) (PVA) primer between the support and the LbL polyamide layer may prevent defect formation. The water permeance and salt rejection of a three layer, PVA-primed, LbL-based PA-TFC membrane are discussed and compared to a membrane made without the PVA primer and a commercially available membrane. Mass transfer resistances are analyzed using a series resistance model and appear to be small or even negligible compared to that of the polyamide layer. Incorporation of a sulfonated co-monomer into the polyamide via LbL is reported. The combination of a PVA primer layer and LbL sequential deposition may expand the range of co-monomers that could be used relative to polyamide membranes prepared by the conventional IP process. 相似文献