373 research outputs found

    XmnI polymorphism: Relation to β-thalassemia phenotype and genotype in Egyptian Children

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    Background: β-Globin mutations with Xmn1 site might be associated with elevatedHbF expression which may in turn ameliorate the severity of β-thalassemia phenotype.Aim of the study: To investigate the frequency of 158 (C > T) XmnI polymorphism among Egyptian Children and young adults with β-thalassemia, to examine the relationship between XmnI polymorphism and β-thalassemia genotypes and phenotypes and to assess the possible relation of XmnI polymorphism and response to hydroxyurea (Hu) therapy.Patients and methods: Seventy-two β-thalassemia patients (37 females; M/F ratio 0.95) with a mean age of 7.53 ± 6.99 were included. Laboratory investigations included Complete blood count (CBC), Hb electrophoresis by high performance liquid chromatography (HPLC), β-thalassemia mutation identification by the reverse dot blot hybridization technique (RDB) and detection of XmnlGg polymorphism by RFLP.Results: The frequency of positive heterozygote XmnI gene polymorphism was 8.3%. Eightythree percent of XmnIGγ+/- patients were never transfused (p= 0.001) and had higher total hemoglobin compared to XmnIGγ-/- (p= 0.01); while mean HbF was higher among XmnIGγ+/- patients compared to the other group but the difference was marginally insignificant (p=0.06).β-Thalassemia mutation IVS II-1 showed relatively higher XmnI polymorphism frequency (50%) and followed by its frequency among 10 undefined β-thalassemia mutations which was 20%. The frequency of positive heterozygote XmnI gene polymorphism was 11.6% among the TI group vs. 3.5% among the TM group (p= 0.4). Among 20 cases who received HU; 5/14 responders vs. 1/ 6 none responder had positive heterozygote XmnI gene polymorphism (p= 1.0).Conclusions and recommendations: In conclusion, molecular determination of genetic markers in childhood will help to identify phenotypes of our patients and to avoid over or under treatment strategies. Further prospective studies concerning the genetic markers that could predict the response to hemoglobin F inducers like hydroxyurea are highly recommended

    In vitro cytotoxicity and induction of apoptosis by multiwalled carbon nanotubes in human peripheral lymphocytes: Correlation with physicochemical properties

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    Multiwalled carbon nanotubes (MWCNTs) consist of more than 80% of the current nanomaterials’ applications worldwide. Despite their wide application, little information is known concerning their impact on human health. The current study aims to identify the in vitro effects of exposure of the human peripheral blood lymphocytes (PBL) to MWCNTs and the possible associations with their physiochemical properties. Two doses (50 and 500 µg/ml) of four different commercially available MWCNTs (obtained from Frascati Laboratory, Sigma Co., Sun Nanotech Co. and Shenzhen Co.) were used in this study. Cell viability and apoptotic activity were evaluated by trypan blue exclusion test and Annexin-V/PI staining in peripheral blood leukocytes (PBL). Physicochemical properties of the different MWCNTs were determined and correlated with the cytotoxicity results after exposure for 12 and 48 h. Results indicate that PBL exposed to MWCNTs showed decreased cell viability and increased apoptosis in a dose- and time-dependent manner. The Pearson’s correlation test showed a lack of relationship between diameter of nanoparticles and their pro-apoptotic activity (r2= 0.282), whereas significant correlations were found between pro-apoptotic activity and the presence of some metal contaminants such as nickel, cobalt and gold (r2= 0.919, 0.698 and 0.520, respectively). Our results therefore suggest that carbon nanotubes at high concentrations lowered cell viability in vitro and induced apoptosis in human cells in vitro. In addition, the results indicate that metal contaminants in carbon nanotubes may be causative of some of the adverse outcomes observed. Finally, our finding provides important information on the biohazard potential of some carbon nanotubes in humans.Key words: Multiwalled, carbon, nanotubes, cytotoxicity, apoptosis, flow cytometry, viability,  lymphocytes

    Effect of Marginal-Quality Irrigation on Accumulation of some Heavy Metals (Mn, Pb, and Zn) in TypicTorripsamment Soils and Food Crops

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    Lack of active sorption sites in sandy soils renders metals added by irrigation water more labile and increases their soil-to-plant transfer. Thus, this study investigated the long-term impacts of irrigation using sewage effluents and contaminated groundwater on metal accumulations in TypicTorripsamment soils, and edible parts of food crops. Nine sites in El-Gabal El-Asfar farm, south-eastern to the Nile Delta of Egypt, were selected. At each site, irrigation water, soil (0-30 cm), and the crop's edible part were sampled in triplicates and analyzed for Mn, Pb, and Zn. Results revealed significant (p < 0.05) differences in metal concentrations among water sources. Thus, constant irrigation caused significant spatial variations in total and available metal contents in soils. Total contents of Pb (in four sites) and Zn (in all sites) exceed the lithosphere range, while the available contents of the three metals exceeded the safe limits in all soils. The index of geo-accumulation indicated no Mn pollution but showed elevated pollution risks for Pb and Zn. The three metals showed high availability ratios, proving the effect of light soil texture. The multivariate statistical analysis indicated that Mn and Zn had similar geochemical behaviors in soils. Metal contents in all crop's edible parts surpassed the safe limits. The bioaccumulation factor (BAF) was less than 1.0 for Mn and Zn but higher than 1.0 for Pb. The highest BAFs occurred in cabbage leaves, indicating the phytoextraction potential of this species. Sufficient water treatment and proper remediation techniques are recommended to alleviate metal accumulation in food crops and their transfer via the food chain

    X-Ray Spectral Study of AGN Sources Content in Some Deep Extragalactic XMM-Newton Fields

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    We undertake a spectral study of a sample of bright X-ray sources taken from six XMM-Newton fields at high galactic latitudes, where AGN are the most populous class. These six fields were chosen such that the observation had an exposure time more than 60 ksec, had data from the EPIC-pn detector in the full-Frame mode and lying at high galactic latitude b>25o|b| > 25^o . The analysis started by fitting the spectra of all sources with an absorbed power-law model, and then we fitted all the spectra with an absorbed power-law with a low energy black-body component model.The sources for which we added a black body gave an F-test probability of 0.01 or less (i.e. at 99% confidence level), were recognized as sources that display soft excess. We perform a comparative analysis of soft excess spectral parameters with respect to the underlying power-law one for sources that satisfy this criterion. Those sources, that do not show evidence for a soft excess, based on the F-test probability at a 99% confidence level, were also fitted with the absorbed power-law with a low energy black-body component model with the black-body temperature fixed at 0.1 and 0.2 keV. We establish upper limits on the soft excess flux for those sources at these two temperatures. Finally we have made use of Aladdin interactive sky atlas and matching with NASA/IPAC Extragalactic Database (NED) to identify the X-ray sources in our sample. For those sources which are identified in the NED catalogue, we make a comparative study of the soft excess phenomenon for different types of systems

    Analytical and mathematical methods for revealing hidden details in ancient manuscripts and paintings: A review

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    In this work, a critical review of the current nondestructive probing and image analysis approaches is presented, to revealing otherwise invisible or hardly discernible details in manuscripts and paintings relevant to cultural heritage and archaeology. Multispectral imaging, X-ray fluorescence, Laser-Induced Breakdown Spectroscopy, Raman spectroscopy and Thermography are considered, as techniques for acquiring images and spectral image sets; statistical methods for the analysis of these images are then discussed, including blind separation and false colour techniques. Several case studies are presented, with particular attention dedicated to the approaches that appear most promising for future applications. Some of the techniques described herein are likely to replace, in the near future, classical digital photography in the study of ancient manuscripts and paintings

    Growth and nutrition of cowpea (Vigna unguiculata) under water deficit as influenced by microbial inoculation via seed coating

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    Drought can drastically reduce cowpea [Vigna unguiculata (L.) Walp.] biomass and grain yield. The application of plant growth‐promoting rhizobacteria and arbuscular mycorrhizal fungi can confer resistance to plants and reduce the effects of environmental stresses, including drought. Seed coating is a technique which allows the application of minor amounts of microbial inocula. Main effects of the factors inoculation and water regime showed that: severe or moderate water deficit had a general negative impact on cowpea plants; total biomass production, seed weight and seed yield were enhanced in plants inoculated with P. putida; inoculation of R. irregularis significantly increased nitrogen (N) and phosphorus (P) shoot concentrations; and R. irregularis enhanced both chlorophyll b and carotenoids contents, particularly under severe water deficit. Plants inoculated with P. putida + R. irregularis had an increase in shoot P concentration of 85% and 57%, under moderate and severe water deficit, respectively. Singly inoculated P. putida improved potassium shoot concentration by 25% under moderate water deficit. Overall, in terms of agricultural productivity the inoculation of P. putida under water deficit might be promising. Seed coating has the potential to be used as a large‐scale delivery system of beneficial microbial inoculants.info:eu-repo/semantics/publishedVersio

    S-system theory applied to array-based GNSS ionospheric sensing

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    The GPS carrier-phase and code data have proven to be valuable sources of measuring the Earth’s ionospheric total electron content (TEC). With the development of new GNSSs with multi frequency data, many more ionosphere-sensing combinations of different precision can be formed as input of ionospheric modelling. We present the general way of interpreting such combinations through an application of S-system theory and address how their precision propagates into that of the unbiased TEC solution. Presenting the data relevant to TEC determination, we propose the usage of an array of GNSS antennas to improve the TEC precision and to expedite the rather long observational time-span required for high-precision TEC determination

    HACE1 deficiency causes an autosomal recessive neurodevelopmental syndrome

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    Background: The genetic etiology of neurodevelopmental defects is extremely diverse, and the lack of distinctive phenotypic features means that genetic criteria are often required for accurate diagnostic classification. We aimed to identify the causative genetic lesions in two families in which eight affected individuals displayed variable learning disability, spasticity and abnormal gait. Methods: Autosomal recessive inheritance was suggested by consanguinity in one family and by sibling recurrences with normal parents in the second. Autozygosity mapping and exome sequencing, respectively, were used to identify the causative gene. Results: In both families, biallelic loss-of-function mutations in HACE1 were identified. HACE1 is an E3 ubiquitin ligase that regulates the activity of cellular GTPases, including Rac1 and members of the Rab family. In the consanguineous family, a homozygous mutation p.R219* predicted a truncated protein entirely lacking its catalytic domain. In the other family, compound heterozygosity for nonsense mutation p.R748* and a 20-nt insertion interrupting the catalytic HECT domain was present; Western analysis of patient cells revealed an absence of detectable HACE1 protein. Conclusion: HACE1 mutations underlie a new autosomal recessive neurodevelopmental disorder. Previous studies have implicated HACE1 as a tumour suppressor gene; however, since cancer predisposition was not observed either in homozygous or heterozygous mutation carriers, this concept may require re-evaluation

    From Profile to Surface Monitoring: SPC for Cylindrical Surfaces Via Gaussian Processes

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    Quality of machined products is often related to the shapes of surfaces that are constrained by geometric tolerances. In this case, statistical quality monitoring should be used to quickly detect unwanted deviations from the nominal pattern. The majority of the literature has focused on statistical profile monitoring, while there is little research on surface monitoring. This paper faces the challenging task of moving from profile to surface monitoring. To this aim, different parametric approaches and control-charting procedures are presented and compared with reference to a real case study dealing with cylindrical surfaces obtained by lathe turning. In particular, a novel method presented in this paper consists of modeling the manufactured surface via Gaussian processes models and monitoring the deviations of the actual surface from the target pattern estimated in phase I. Regardless of the specific case study in this paper, the proposed approach is general and can be extended to deal with different kinds of surfaces or profiles
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