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991.
992.
Laurena Holleran Mohamed Ahmed Heike Anderson-Schmidt John McFarland Louise Emsell Alexander Leemans Cathy Scanlon Peter Dockery Peter McCarthy Gareth J Barker Colm McDonald Dara M Cannon 《Neuropsychopharmacology》2014,39(4):944-954
Diffusion MRI investigations in schizophrenia provide evidence of abnormal white matter (WM) microstructural organization as indicated by reduced fractional anisotropy (FA) primarily in interhemispheric, left frontal and temporal WM. Using tract-based spatial statistics (TBSS), we examined diffusion parameters in a sample of patients with severe chronic schizophrenia. Diffusion MRI data were acquired on 19 patients with chronic severe schizophrenia and 19 age- and gender-matched healthy controls using a 64 gradient direction sequence, (b=1300 s/mm2) collected on a Siemens 1.5T MRI scanner. Diagnosis of schizophrenia was determined by Diagnostic and Statistical Manual for Mental Disorders 4th Edition (DSM-IV) Structured Clinical Interview for DSM disorder (SCID). Patients were treatment resistance, having failed to respond to at least two antipsychotic medications, and had prolonged periods of moderate to severe positive or negative symptoms. Analysis of diffusion parameters was carried out using TBSS. Individuals with chronic severe schizophrenia had significantly reduced FA with corresponding increased radial diffusivity in the genu, body, and splenium of the corpus callosum, the right posterior limb of the internal capsule, right external capsule, and the right temporal inferior longitudinal fasciculus. There were no voxels of significantly increased FA in patients compared with controls. A decrease in splenium FA was shown to be related to a longer illness duration. We detected widespread abnormal diffusivity properties in the callosal and temporal lobe WM regions in individuals with severe chronic schizophrenia who have not previously been exposed to clozapine. These deficits can be driven by a number of factors that are indistinguishable using in vivo diffusion-weighted imaging, but may be related to reduced axonal number or packing density, abnormal glial cell arrangement or function, and reduced myelin. 相似文献
993.
A temporary confinement of the quaternary tetramethylammonium tetrafluoroborate (TMA BF4) salt among polyamide molecules has been used for the preparation of aliphatic polyamide nylon 6,6 fibres with high-modulus and high-strength properties. In this method, the suppression or the weakening of the hydrogen bonds between the nylon 6,6 segments has been applied during the conventional low-speed melt spinning process. Thereafter, after the complete hot-drawing stage, the quaternary ammonium salt is fully extracted from the drawn 3 wt.% salt-confined fibres and the nascent fibres are, subsequently, thermally stabilized. The structural developments that are acquired in the confined-nylon 6,6 fibres are ascribed to the developments of the overall fibres’ properties due to the confinement process. Surprisingly, unlike the neat nylon 6,6 fibres, the X-ray diffraction (XRD) patterns of the as-spun salt-confined fibres have shown diminishing of the (110)/(010) diffraction plane that obtained pseudohexagonal-like β’ structural phase. Moreover, the β’ pseudohexagonal-like to α triclinic phase transitions took-place due to the hot-drawing stage (draw-induced phase transitions). Interestingly, the hot-drawing of the as-spun salt-confined nylon 6,6 fibres achieved the same maximum draw ratio of 5.5 at all of the drawing temperatures of 120, 140 and 160 °C. The developments that happened produced the improved values of 43.32 cN/dtex for the tensile-modulus and 6.99 cN/dtex for the tensile-strength of the reverted fibres. The influences of the TMA BF4 salt on the structural developments of the crystal orientations, on the morphological structures and on the improvements of the tensile properties of the nylon 6,6 fibres have been intensively studied. 相似文献
994.
Nico Joel Halwe Marco Gorka Bernd Hoffmann Melanie Rissmann Angele Breithaupt Martin Schwemmle Martin Beer Ahmed Kandeil Mohamed A. Ali Ghazi Kayali Donata Hoffmann Anne Balkema-Buschmann 《Viruses》2021,13(4)
Influenza A viruses (IAV) of subtype H9N2, endemic in world-wide poultry holdings, are reported to cause spill-over infections to pigs and humans and have also contributed substantially to recent reassortment-derived pre-pandemic zoonotic viruses of concern, such as the Asian H7N9 viruses. Recently, a H9N2 bat influenza A virus was found in Egyptian fruit bats (Rousettus aegyptiacus), raising the question of whether this bat species is a suitable host for IAV. Here, we studied the susceptibility, pathogenesis and transmission of avian and bat-related H9N2 viruses in this new host. In a first experiment, we oronasally inoculated six Egyptian fruit bats with an avian-related H9N2 virus (A/layer chicken/Bangladesh/VP02-plaque/2016 (H9N2)). In a second experiment, six Egyptian fruit bats were inoculated with the newly discovered bat-related H9N2 virus (A/bat/Egypt/381OP/2017 (H9N2)). While R. aegyptiacus turned out to be refractory to an infection with H9N2 avian-type, inoculation with the bat H9N2 subtype established a productive infection in all inoculated animals with a detectable seroconversion at day 21 post-infection. In conclusion, Egyptian fruit bats are most likely not susceptible to the avian H9N2 subtype, but can be infected with fruit bat-derived H9N2. H9-specific sero-reactivities in fruit bats in the field are therefore more likely the result of contact with a bat-adapted H9N2 strain. 相似文献
995.
Gamma delta (γδ) T cells form an unconventional subset of T lymphocytes that express a T cell receptor (TCR) consisting of γ and δ chains. Unlike conventional αβ T cells, γδ T cells share the immune signature of both the innate and the adaptive immunity. These features allow γδ T cells to act in front-line defense against infections and tumors, rendering them an attractive target for immunotherapy. The role of γδ T cells in the immune response to cytomegalovirus (CMV) has been the focus of intense research for several years, particularly in the context of transplantation, as CMV reactivation remains a major cause of transplant-related morbidity and mortality. Therefore, a better understanding of the mechanisms that underlie CMV immune responses could enable the design of novel γδ T cell-based therapeutic approaches. In this regard, the advent of next-generation sequencing (NGS) and single-cell TCR sequencing have allowed in-depth characterization of CMV-induced TCR repertoire changes. In this review, we try to shed light on recent findings addressing the adaptive role of γδ T cells in CMV immunosurveillance and revisit CMV-induced TCR reshaping in the era of NGS. Finally, we will demonstrate the favorable and unfavorable effects of CMV reactive γδ T cells post-transplantation. 相似文献
996.
Yavuz Mercan Gladys Atim Ahmed E. Kayed M. Ekin Azbazdar Ahmed Kandeil Mohamed A. Ali Adam Rubrum Pamela McKenzie Richard J. Webby Bernard Erima Fred Wabwire-Mangen Qouilazoni A. Ukuli Titus Tugume Denis K. Byarugaba Ghazi Kayali Mariette F. Ducatez Zeynep A. Koer 《Viruses》2021,13(4)
Genetic analysis of circulating avian influenza viruses (AIVs) in wild birds at different geographical regions during the same period could improve our knowledge about virus transmission dynamics in natural hosts, virus evolution as well as zoonotic potential. Here, we report the genetic and molecular characterization of H6N2 influenza viruses isolated from migratory birds in Turkey, Egypt, and Uganda during 2017–2018. The Egyptian and Turkish isolates were genetically closer to each other than they were to the virus isolated from Uganda. Our results also suggest that multiple reassortment events were involved in the genesis of the isolated viruses. All viruses contained molecular markers previously associated with increased replication and/or pathogenicity in mammals. The results of this study indicate that H6N2 viruses carried by migratory birds on the West Asian/East African and Mediterranean/Black Sea flyways have the potential to transmit to mammals including humans. Additionally, adaptation markers in these viruses indicate the potential risk for poultry, which also increases the possibility of human exposure to these viruses. 相似文献
997.
Background:The Egyptian National Committee of Viral Hepatitis program is the leading national hepatitis C virus (HCV) management program globally. However, limited data is available about the effect of the new directly acting antiviral agents on the cardiovascular system.Objectives:Our study aimed to assess the safety of the relatively new directly acting antiviral agents approved by the National Health Committee in Egypt to treat patients infected with hepatitis C virus who have midrange left ventricular ejection fraction.Methods:This multicenter study included 400 successive patients with an ejection fraction (40–49%) from May 2017 to December 2019. We classified them into two groups: Group I (Child A), who received Sofosbuvir and Daclatasvir for twelve weeks, and Group II (Child B), who received Sofosbuvir, Daclatasvir, and Ribavirin for twelve weeks. Patients were evaluated for their symptoms, ejection fraction, brain natriuretic peptide, lipid profile, fasting blood glucose, fasting insulin, Homeostatic Model Assessment of Insulin Resistance levels, and Holter monitoring (just before the start of treatment and within three days after completing therapy).Results:We found New York Heart Association Class, ejection fraction, brain natriuretic peptide, premature ventricular contractions burden, as well as highest and lowest heart rate did not show a statistically significant difference in both groups after treatment. The treatment did not cause bradycardia or non-sustained ventricular tachycardia. Fasting blood glucose and fasting insulin levels declined, with improved insulin resistance after treatment in both groups. Both low and high-density lipoprotein cholesterol increased after treatment in Group II.Conclusions:Both regimens of directly acting antiviral agents used in Egypt to treat chronic hepatitis C virus infection are safe in patients with New York Heart Association Class I and II with midrange left ventricular ejection fraction (40–49%). There are beneficial metabolic changes following HCV clearance as an improvement of insulin resistance. 相似文献
998.
Equilibrium molecular dynamics simulation has been carried out for the thermal transport characterization of nanometer sized carbon and silicon doped stanene nanoribbon (STNR). The thermal conduction properties of doped stanene nanostructures are yet to be explored and hence in this study, we have investigated the impact of carbon and silicon doping concentrations as well as doping patterns namely single doping, double doping and edge doping on the thermal conductivity of nanometer sized zigzag STNR. The room temperature thermal conductivities of 15 nm × 4 nm doped zigzag STNR at 2% carbon and silicon doping concentration are computed to be 9.31 ± 0.33 W m−1 K−1 and 7.57 ± 0.48 W m−1 K−1, respectively whereas the thermal conductivity for the pristine STNR of the same dimension is calculated as 1.204 ± 0.21 W m−1 K−1. We find that the thermal conductivity of both carbon and silicon doped STNR increases with the increasing doping concentration for both carbon and silicon doping. The magnitude of increase in STNR thermal conductivity due to carbon doping has been found to be greater than that of silicon doping. Different doping patterns manifest different degrees of change in doped STNR thermal conductivity. Double doping pattern for both carbon and silicon doping induces the largest extent of enhancement in doped STNR thermal conductivity followed by single doping pattern and edge doping pattern respectively. The temperature and width dependence of doped STNR thermal conductivity has also been studied. For a particular doping concentration, the thermal conductivity of both carbon and silicon doped STNR shows a monotonic decaying trend at elevated temperatures while an opposite pattern is observed for width variation i.e. thermal conductivity increases with the increase in ribbon width. Such comprehensive study on doped stanene would encourage further investigation on the proper optimization of thermal transport characteristics of stanene nanostructures and provide deep insight in realizing the potential application of doped STNR in thermoelectric as well as thermal management of stanene based nanoelectronic devices.Tunable thermal transport of doped stanene nanoribbon considering the impact of doping concentration, doping pattern, temperature and nanoribbon width. 相似文献
999.
Osama Hamid Ahmed Eltelbany Abdul Mohammed Khaled Alsabbagh Alchirazi Sushrut Trakroo Imad Asaad 《Annals of hepatology》2022,27(5):100727
Introduction and objectivesNon-alcoholic steatohepatitis (NASH) is a severe form of non-alcoholic fatty liver disease (NAFLD) that can progress to liver cirrhosis, liver failure and hepatocellular carcinoma. It is the second leading cause of liver transplant in the US. We aim to investigate the prevalence, demographics and risk factors NASH patients in the US.Patients and methodsWe used a large database (Explorys IBM) that aggregates electronic health records from 26 nationwide healthcare systems. We identified adults with NASH between 2010-2020. Demographics including age, gender and race were collected. NASH risk factors including Diabetes Millets (DM), Hyperlipidemia (HLD), Hypertension (HTN) and Obesity were also collected. Cochran-Armitage test was used to assess the statistical significance of year-by-year trend. Univariable and multivariable logistic regression were used to estimate the odds ratio (OR) of risk factors.ResultsNASH annual prevalence rate increased from 1.51% in 2010 to 2.79% in 2020 (p < 0.0001). The proportion of patients with NASH by gender was 54.1% female vs 45.9% male (OR 1.04 [0.91-1.11]). Caucasian had higher odds of NASH than non-Caucasian (OR 1.42 [1.31-1.54]). NASH is strongly associated with DM and obesity (OR 18.61 [17.35-19.94]) and (OR 20.97 [17.87-23.21]), respectively. Other components of metabolic syndrome were associated with NASH to a lesser degree; HTN (OR 3.24 [3.20-3.28]) and HLD (OR 4.93 [4.85-4.01]).ConclusionThe prevalence of NASH has significantly increased in the US in the last decade. This is likely related to the increased prevalence of risk factors as well as increased awareness of the disease. 相似文献
1000.
Emad Elshebini Hozaifa Elsawah Taghreed Fathy Sherry Abdelrahman Omar Youssif Soaad Ashraf Nibal Mourad Mohamed Elnaggar Ahmed Elshebiny Shymaa Daif Enas Zahran 《The Egyptian Rheumatologist》2021,43(2):167-171
BackgroundInflammatory diseases can interfere with adequate nutrition and even lead to a malnourished state. Nutritional deficiency manifestations may be similar to rheumatologic manifestations.Aim of the workTo assess whether malnutrition is an associated feature of rheumatic diseases (RDs).Patients and methodsA multicenter study included Egyptian patients with different RDs; nutrition measurements and common features of deficiency were assessed; general appearance, skin, hair/nail changes, spooning of nails, night blindness, mouth problems, edema, tetany, dysphagia, diarrhea, thyromegaly, loss of appetite and weight loss.ResultsThe study included 284 patients with various RDs: rheumatoid arthritis (RA) (n = 128), systemic lupus erythematosus (n = 120), Behçet’s disease (n = 17), spondyloarthritis (n = 6), systemic sclerosis (n = 5), dermatomyositis (n = 2), relapsing polychondritis (n = 2), and one patient each with familial Mediterranean fever, Gout, Still's disease and undifferentiated connective tissue disease. Muscle wasting was present in 44(15.5%) patients, spooning of nails in 26(9.2%), night blindness in 38(13.4%), glossitis in 48(16.9%), tetany in 32(11.3%) and loss of appetite in 51(18%). Although there was significant differences among RDs in some nutritional deficiency signs, the type and their durations did not significantly affect symptoms or signs of nutritional deficiency, while age was associated with peripheral edema (p = 0.014) and tetany (p = 0.009); azathioprine was associated with hair/nail changes (p = 0.04); methotrexate with peripheral edema and hair/nail changes (p = 0.002, p = 0.01 respectively); and hydroxychloroquine was negatively associated with skin rash, wasting and hair/nail changes (p = 0.011, p = 0.001 and p < 0.0001 respectively).ConclusionNutritional deficiency is common among RD patients especially elderly and should be monitored frequently regardless type and onset. 相似文献