Study of amino acid disorders among a high risk group of Egyptian infants and children

Aim of the work: The present work aimed at investigating infants (In neonatal and post neonatal period) and children suspected of having inborn errors of metabolism with unexplained mental retardation. The frequency pattern of the various amino acid disorders, in a group of selected infants and children was done to document the prevalence of various amino acid disorders among Egyptian children. Patients and Method: In this study, recent methods to investigate such disorders have been carried out by amino acid analyzer which detects levels of amino acids. Extended metabolic screen which also detects amino acid disorders, organic acid disorders and the defects of fatty acid oxidation has been carried out. These recent methods have therefore the potential of yielding information on the physiological and pathophysiological status of different metabolic pathways, as well as their interrelationship. Results: The total number of cases attending the outpatient clinic during the period of study were 1343 index cases, among them 50 index cases (3.72%) were suspected of having inborn errors of amino acid and, 20 cases (40%) of them have confirmed positive inborn errors of amino acid metabolism. Concerning the confirmed 20 cases, their ages ranged from 5 days to 11 years with a mean of 54.75±33.09 months with equally sex distribution. The overall consanguinity rate recorded was 65%, while the family history of the similarly affected cases was 30%. The main clinical findings included mental retardation 85%, convulsions 40%, and hypo pigmentation 75%, micro-cephally 15%. Associated anomalies were present in 35% of cases. Among them eye anomalies were the most common (8%). Conclusion: The prevalence of amino-acido-pathies during the period of the study was 1.5% (Of 20 studied cases), among them PKU was found to be the commonest amino-acido-pathies 1.11%, while the remaining diagnosed cases representing 0.07% for each. Keywords: Amino acid disorders, high risk, children Egypt. J. Hum. Genet Vol. 8 (2) 2007: pp. 173-19

Mid-infrared top-gated Ge/Ge0.82_{0.82}Sn0.18_{0.18} nanowire phototransistors

Achieving high crystalline quality Ge$_{1-x}$Sn$_{x}$ semiconductors at Sn content exceeding 10\% is quintessential to implementing the long sought-after silicon-compatible mid-infrared photonics. Herein, by using sub-20 nm Ge nanowires as compliant growth substrates, Ge$_{1-x}$Sn$_{x}$ alloys with a Sn content of 18\% exhibiting a high composition uniformity and crystallinity along a few micrometers in the nanowire growth direction were demonstrated. The measured bandgap energy of the obtained Ge/Ge$_{0.82}$Sn$_{0.18}$ core/shell nanowires is 0.322 eV enabling the mid-infrared photodetection with a cutoff wavelength of 3.9 $\mu$m. These narrow bandgap nanowires were also integrated into top-gated field-effect transistors and phototransistors. Depending on the gate design, these demonstrated transistors were found to exhibit either ambipolar or unipolar behavior with a subthreshold swing as low as 228 mV/decade measured at 85 K. Moreover, varying the top gate voltage from -1 V to 5 V yields nearly one order of magnitude increase in the photocurrent generated by the nanowire phototransistor under a 2330 nm illumination. This study shows that the core/shell nanowire architecture with a super thin core not only mitigates the challenges associated with strain buildup observed in thin films but also provides a promising platform for all-group IV mid-infrared photonics and nanoelectronics paving the way toward sensing and imaging applications

The impact of image dynamic range on texture classification of brain white matter

<p>Abstract</p> <p>Background</p> <p>The Greylevel Cooccurrence Matrix method (COM) is one of the most promising methods used in Texture Analysis of Magnetic Resonance Images. This method provides statistical information about the spatial distribution of greylevels in the image which can be used for classification of different tissue regions. Optimizing the size and complexity of the COM has the potential to enhance the reliability of Texture Analysis results. In this paper we investigate the effect of matrix size and calculation approach on the ability of COM to discriminate between peritumoral white matter and other white matter regions.</p> <p>Method</p> <p>MR images were obtained from patients with histologically confirmed brain glioblastoma using MRI at 3-T giving isotropic resolution of 1 mm³. Three Regions of Interest (ROI) were outlined in visually normal white matter on three image slices based on relative distance from the tumor: one peritumoral white matter region and two distant white matter regions on both hemispheres. Volumes of Interest (VOI) were composed from the three slices. Two different calculation approaches for COM were used: i) Classical approach (CCOM) on each individual ROI, and ii) Three Dimensional approach (3DCOM) calculated on VOIs. For, each calculation approach five dynamic ranges (number of greylevels N) were investigated (N = 16, 32, 64, 128, and 256).</p> <p>Results</p> <p>Classification showed that peritumoral white matter always represents a homogenous class, separate from other white matter, regardless of the value of N or the calculation approach used. The best test measures (sensitivity and specificity) for average CCOM were obtained for N = 128. These measures were also optimal for 3DCOM with N = 128, which additionally showed a balanced tradeoff between the measures.</p> <p>Conclusion</p> <p>We conclude that the dynamic range used for COM calculation significantly influences the classification results for identical samples. In order to obtain more reliable classification results with COM, the dynamic range must be optimized to avoid too small or sparse matrices. Larger dynamic ranges for COM calculations do not necessarily give better texture results; they might increase the computation costs and limit the method performance.</p

The clinical significance of tumor infiltrating lymphoctyes in breast cancer: does subtype matter?

Tumor infiltrating lymphocytes (TILs) are commonly detected in breast tumors but their bearing on disease outcome is uncertain. The importance of TILs appears to be subtype-specific and varies depending on the histologic characteristics of the tumor. As our understanding of tumorigenesis is increasing the relevance of immunobiology will become apparent

Regional changes in reactive hyperemic blood flow during exercise training: time-course adaptations

BACKGROUND: Few studies have examined the time-course of localized exercise training on regional blood flow in humans. The study examined the influence of handgrip exercise training on forearm reactive hyperemic blood flow and vascular resistance in apparently healthy men. METHODS: Forearm blood flow and vascular resistance were evaluated, in 17 individuals [Age: 22.6 ± 3.5], in both arms, at rest and following 5 minutes of arterial occlusion, using strain gauge plethysmography, prior to training (V1) and every week thereafter (V2-5) for 4 weeks. Handgrip exercise was performed in the non-dominant arm 5 d/wk for 20 minutes at 60% of maximum voluntary contraction, while the dominant arm served as control. RESULTS: Resting HR, BP, and forearm blood flow and vascular resistance were not altered with training. The trained arm handgrip strength and circumference increased by 14.5% (p = 0.014) and 1.56% (p = 0.03), respectively. ANOVA tests revealed an arms by visit interaction for the trained arm for reactive hyperemic blood flow (p = 0.02) and vascular resistance (p = 0.009). Post-hoc comparison demonstrated increased reactive hyperemic blood flow (p = 0.0013), and decreased post-occlusion vascular resistance (p = 0.05), following the 1(st )week of training, with no significant changes in subsequent visits. CONCLUSION: The results indicate unilateral improvements in forearm reactive hyperemic blood flow and vascular resistance following 1 week of handgrip exercise training and leveled off for the rest of the study

Image Texture Characterization Using the Discrete Orthonormal S-Transform

We present a new efficient approach for characterizing image texture based on a recently published discrete, orthonormal space-frequency transform known as the DOST. We develop a frequency-domain implementation of the DOST in two dimensions for the case of dyadic frequency sampling. Then, we describe a rapid and efficient approach to obtain local spatial frequency information for an image and show that this information can be used to characterize the horizontal and vertical frequency patterns in synthetic images. Finally, we demonstrate that DOST components can be combined to obtain a rotationally invariant set of texture features that can accurately classify a series of texture patterns. The DOST provides the computational efficiency and multi-scale information of wavelet transforms, while providing texture features in terms of Fourier frequencies. It outperforms leading wavelet-based texture analysis methods

Lack of robustness of textural measures obtained from 3D brain tumor MRIs impose a need for standardization

Purpose Textural measures have been widely explored as imaging biomarkers in cancer. However, their robustness under dynamic range and spatial resolution changes in brain 3D magnetic resonance images (MRI) has not been assessed. The aim of this work was to study potential variations of textural measures due to changes in MRI protocols. Materials and methods Twenty patients harboring glioblastoma with pretreatment 3D T1-weighted MRIs were included in the study. Four different spatial resolution combinations and three dynamic ranges were studied for each patient. Sixteen three-dimensional textural heterogeneity measures were computed for each patient and configuration including co-occurrence matrices (CM) features and run-length matrices (RLM) features. The coefficient of variation was used to assess the robustness of the measures in two series of experiments corresponding to (i) changing the dynamic range and (ii) changing the matrix size. Results No textural measures were robust under dynamic range changes. Entropy was the only textural feature robust under spatial resolution changes (coefficient of variation under 10% in all cases). Conclusion Textural measures of three-dimensional brain tumor images are not robust neither under dynamic range nor under matrix size changes. Standards should be harmonized to use textural features as imaging biomarkers in radiomic-based studies. The implications of this work go beyond the specific tumor type studied here and pose the need for standardization in textural feature calculation of oncological images

Observation of associated near-side and away-side long-range correlations in √sNN=5.02 TeV proton-lead collisions with the ATLAS detector

Two-particle correlations in relative azimuthal angle (Δϕ) and pseudorapidity (Δη) are measured in √sNN=5.02  TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1  μb-1 of data as a function of transverse momentum (pT) and the transverse energy (ΣETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Δη|<5) “near-side” (Δϕ∼0) correlation that grows rapidly with increasing ΣETPb. A long-range “away-side” (Δϕ∼π) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ΣETPb, is found to match the near-side correlation in magnitude, shape (in Δη and Δϕ) and ΣETPb dependence. The resultant Δϕ correlation is approximately symmetric about π/2, and is consistent with a dominant cos⁡2Δϕ modulation for all ΣETPb ranges and particle pT

Search for the neutral Higgs bosons of the minimal supersymmetric standard model in pp collisions at root s=7 TeV with the ATLAS detector

A search for neutral Higgs bosons of the Minimal Supersymmetric Standard Model (MSSM) is reported. The analysis is based on a sample of proton-proton collisions at a centre-of-mass energy of 7TeV recorded with the ATLAS detector at the Large Hadron Collider. The data were recorded in 2011 and correspond to an integrated luminosity of 4.7 fb-1 to 4.8 fb-1. Higgs boson decays into oppositely-charged muon or τ lepton pairs are considered for final states requiring either the presence or absence of b-jets. No statistically significant excess over the expected background is observed and exclusion limits at the 95% confidence level are derived. The exclusion limits are for the production cross-section of a generic neutral Higgs boson, φ, as a function of the Higgs boson mass and for h/A/H production in the MSSM as a function of the parameters mA and tan β in the mhmax scenario for mA in the range of 90GeV to 500 GeV. Copyright CERN