688 research outputs found

    14-Bromo-12-chloro-2,16-dioxapentacyclohenicosa-3(8),10,12,14-tetraene-7,20-dione

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    In the title compound, C19H16BrClO4, both the fused xanthene rings and one of the cyclohexane rings adopt envelope conformations, while the other cyclohexane ring is in a chair conformation. In the crystal, molecules are linked by C-H...O hydrogen bonds, forming infinite chains running along [10-1] incorporating R22(16) ring motifs. In addition, C-H...[pi] interactions and weak [pi]-[pi] stacking interactions [centroid-centroid distance = 3.768 (3) Å] help to consolidate the packing

    On-demand network slicing using SDN/NFV-enabled satellite ground segment systems

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    © 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.This paper proposes an architecture framework for the realization of on-demand satellite network slicing that is built on the introduction of Software Defined Networking (SDN) and Network Function Virtualization (NFV) technologies. In this way, service delivery with satellite networks is shifted from a network for connectivity model to a network for service model with a high degree of service customization and adaptability, including satellite bandwidth on-demand. Under this framework, we study the resource orchestration of satellite network services by formulating the on-demand network slicing as an optimization problem that provides flexible service chaining and provisioning taking into account diversified service requirements. The objective is to determine the optimal resource allocation for supporting a satellite network slice that minimizes resources consumption while meeting service specification requirements such as the end-to-end delay.Peer ReviewedPostprint (author's final draft

    Expression of the Fluoroquinolones Efflux Pump Genes acrA and mdfA in Urinary Escherichia coli Isolates

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    Escherichia coli is one of the most frequent causes of urinary tract infections. Efflux system overexpression is reported to contribute to E. coli resistance to several antibiotics. Our aim in this study was to investigate the relation between antibiotic resistance and the expres­sion of the efflux pump genes acrA and mdfA in E. coli by real-time reverse transcription-PCR. We tested the in vitro susceptibilities to 12 antibiotics in 28 clinical isolates of E. coli obtained from urine samples. We also determined the minimum inhibitory concentrations of levofloxacin to these samples. We then revealed significant correlations between the overexpression of both mdfA and acrA and MICs of levofloxacin. In conclusion, we demonstrated that the increased expression of efflux pump genes such as mdfA and acrA can lead to levofloxacin resistance in E. coli. These findings contribute to further understanding of the molecular mechanisms of efflux pump systems and how they contribute to antibiotic resistance

    Multiplicity of 5' Cap Structures Present on Short RNAs

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    Most RNA molecules are co- or post-transcriptionally modified to alter their chemical and functional properties to assist in their ultimate biological function. Among these modifications, the addition of 5' cap structure has been found to regulate turnover and localization. Here we report a study of the cap structure of human short (<200 nt) RNAs (sRNAs), using sequencing of cDNA libraries prepared by enzymatic pretreatment of the sRNAs with cap sensitive-specificity, thin layer chromatographic (TLC) analyses of isolated cap structures and mass spectrometric analyses for validation of TLC analyses. Processed versions of snoRNAs and tRNAs sequences of less than 50 nt were observed in capped sRNA libraries, indicating additional processing and recapping of these annotated sRNAs biotypes. We report for the first time 2,7 dimethylguanosine in human sRNAs cap structures and surprisingly we find multiple type 0 cap structures (mGpppC, 7mGpppG, GpppG, GpppA, and 7mGpppA) in RNA length fractions shorter than 50 nt. Finally, we find the presence of additional uncharacterized cap structures that wait determination by the creation of needed reference compounds to be used in TLC analyses. These studies suggest the existence of novel biochemical pathways leading to the processing of primary and sRNAs and the modifications of their RNA 5' ends with a spectrum of chemical modifications

    An incremental approach for real-time Big Data visual analytics

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    In the age of Big Data, the real-time interactive visualization is a challenge due to latency of executing calculation over terabytes (even, petabytes) datasets. The execution of an operation has to finish before its outcome is displayed, which would be an issue in those scenarios where low-latency responses are required. To address such a requirement, this paper introduces a new approach for real-time visualization of extremely large data-at-rest as well as data-in-motion by showing intermediate results as soon as they become available. This should allow the data analyst to take decisions in real-time

    Which microbial factors really are important in Pseudomonas aeruginosa infections?

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    Over the last two decades, tens of millions of dollars have been invested in understanding virulence in the human pathogen, Pseudomonas aeruginosa. However, the top 'hits' obtained in a recent TnSeq analysis aimed at identifying those genes that are conditionally essential for infection did not include most of the known virulence factors identified in these earlier studies. Instead, it seems that P. aeruginosa faces metabolic challenges in vivo, and unless it can overcome these, it fails to thrive and is cleared from the host. In this review, we look at the kinds of metabolic pathways that the pathogen seems to find essential, and comment on how this knowledge might be therapeutically exploited.Work in the MW laboratory is funded by the BBSRC (grant BB/M019411/1) and the EU (Marie Curie Educational Training Network “INTEGRATE”). AC is supported by the Cambridge Trusts. EM is funded by a studentship from the MRC. SB is supported by a Hershel Smith studentship. E-FU is a clinical research fellow funded by the CF Trust (UK), Papworth Hospital NHS Trust and the Wellcome Trust. YA is supported by a scholarship from the Yosef Jameel Foundation. YB is an EPSRC-funded PhD student. Work in the laboratory of AF is supported by the Wellcome Trust. Work in the DRS laboratory is supported by the EPSRC.This is the author accepted manuscript. The final version is available from Future Science Group via http://dx.doi.org/10.2217/fmb.15.10

    Role of Inflammatory Cytokines in Obese and Nonobese Diabetic Children

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    BACKGROUND: Obesity is an expanded health problem worldwide and it is blamed for a startling rise in type 1 diabetes (T1DM), the interaction between obesity, autoimmune processes, and glucose homeostasis is a growing field of study. AIM: This study was undertaken to predict the role of the inflammatory cytokines (interleukin [IL]-17 and IL-10) as biomarkers in early screening for obesity and T1DM and to determine the relation of inflammatory cytokines with diabetic complications especially nephropathy. SUBJECTS AND METHODS: The target group consisted of 92 children with type 1 diabetes children who were diagnosed according to the criteria provided by American Diabetes Association Diabetic; cases were divided into two groups, Group 1 (overweight and obese diabetics) and Group 2 (normal weight diabetic children). The levels of serum IL-17 and IL-10 were assayed in these children by an enzyme-linked immunosorbent assay. Serum triglycerides (TG) and cholesterol levels were measured as well as urinary microalbumin level was estimated for detection of nephropathy. RESULTS: Diabetic overweight and obese children exhibited significantly 3.8 folds more at risk to be bad glycemic control than diabetic children with normal body mass index (BMI). Furthermore, overweight and obese diabetic children displayed significantly 15 times more at risk of having nephropathy than diabetic children with normal BMI. Low serum level of IL 10 and high level of IL 17 showed a significant association with high BMI in diabetic children. High HBA1c, low IL 10, and long disease duration were significantly considered as predominant risk factors for diabetic nephropathy in diabetic children. CONCLUSION: The obtained data from these investigations proved that overweight and obese children have a low serum level of IL-10 and high serum IL-17 levels. The relationship between IL-10/IL-17 can be applied as a good marker for the inflammatory state and these inflammatory interleukins can be employed as biomarkers in early screening for obesity and T1DM. Furthermore, these interleukins can be utilized as a predictor for early diabetic complications, particularly nephropathy

    Breast Milk Macronutrients in Relation to Infants’ Anthropometric Measures

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    BACKGROUND: Breast milk (BM) is the main nutritional source for newborns before they are capable to eat and consume other foods. BM has carbohydrates, lipids, complex proteins, and other biologically active components which have a direct effect on infant growth. AIM: The aim of the study was to correlate anthropometric data of the infant to macronutrients in BM (fat, protein, and carbohydrates) and to find some modifiable issues affecting macronutrient contents of BM for the benefits of upcoming infants. METHODS: One hundred breastfeeding mothers participated in the study, they were recruited from the outpatient clinic, El Demerdash Hospital, Ain Shams University, from September 2019, to December 2019. BM was expressed by an electric pump, macronutrient content was assessed. Anthropometric data of the babies and mothers were obtained, gestational age, parity, age of the women, and the route of birth were recorded. RESULTS: For the macronutrients content of milk, a positive significant correlation was observed between BM fat, protein, and lactose. Infants’ body mass index (BMI) was negatively related to the fat content of BM, while no relation was found between BMI and protein or lactose content of the milk. BM fat content was negatively correlated with gestational age and maternal age. Positive correlations were found between BMI and protein, lactose and infant age. Protein content was negatively correlated with parity. No impact of infant’s sex on BM composition and as regards maternal diet, high protein consumption leading to increase BM protein content. CONCLUSIONS: The current study confirms that BM macronutrient composition has a wide variability; this variability is associated with each macronutrient, respectively. To improve BM composition, one could aim for improving the nutritional balance in lactating women, especially for protein intake. More well-designed longitudinal studies about factors that influence human milk compositions are warranted
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