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81.
Adel M. Abd El-kader Basma Khalaf Mahmoud Dina Hajjar Mamdouh F. A. Mohamed Alaa M. Hayallah Usama Ramadan Abdelmohsen 《RSC advances》2020,10(38):22730
A new triterpenoidal saponin identified as 3-O-[β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranosyl-(1 → 4)-β-d-xylopyranosyl]-2β,3β,16α-trihydroxyolean-12-en-23,28-dioic acid-28-O-α-l-rhamnopyranosyl-(1 → 4)-α-l-rhamnopyranosyl-(1 → 2)-β-d-glucopyranosyl-(1 → 2)-α-l-arabinopyranoside 1 together with a new oleanane triterpene identified as 2β,3β,13α,22α-tetrahydroxy olean-23,28-dioic acid 2 and 6 known compounds (3–8) have been isolated from Gladiolus segetum Ker-Gawl corms. The structural elucidation of the isolated compounds was confirmed using different chemical and spectroscopic methods, including 1D and 2D NMR experiments as well as HR-ESI-MS. Moreover, the in vitro cytotoxic activity of the fractions and that of the isolated compounds 1–8 were investigated against five human cancer cell lines (PC-3, A-549, HePG-2, MCF-7 and HCT-116) using doxorubicin as a reference drug. The results showed that the saponin fraction exhibited potent in vitro cytotoxic activity against the five human cancer cell lines, whereas the maximum activity was exhibited against the PC-3 and A-549 cell lines with the IC50 values of 1.13 and 1.98 μg mL−1, respectively. In addition, compound 1 exhibited potent activity against A-549 and PC-3 with the IC50 values of 2.41 μg mL−1 and 3.45 μg mL−1, respectively. Interestingly, compound 2 showed the maximum activity against PC-3 with an IC50 of 2.01 μg mL−1. These biological results were in harmony with that of the molecular modeling study, which showed that the cytotoxic activity of compound 2 might occur through the inhibition of the HER-2 enzyme.A new triterpenoidal saponin 1, a new oleanane triterpene 2, and 6 known compounds (3–8) have been isolated from Gladiolus segetum Ker-Gawl corms. 相似文献
82.
Wei Hui Mohamed Y. Abd El Rahman Rita Schuck Axel Rentzsch Moustafa Yigitbasi Stanislav Ovroutski Fatima Lunze Felix Berger Hashim Abdul-Khaliq 《Journal of Echocardiography》2013,11(4):130-137
Background
We aimed to assess the existence of myocardial dysfunction and intra-univentricular diastolic asynchrony in patients after Fontan operation.Methods
Twenty patients after Fontan procedure and 30 age-matched controls were included in the study. The global function of the univentricular heart was analyzed by the Tei index. Regional myocardial velocities and strain of the univentricular heart including the rudimentary right ventricle (RV) were quantified by tissue Doppler imaging. Intra-univentricular or intra left ventricular (LV) diastolic delay was measured from the difference of diastolic intervals (time to peak early diastolic velocity), measured at LV lateral wall and the rudimental RV wall in patients, or LV lateral wall and the ventricular septum in controls.Results
Compared to the control group, patients after Fontan operation had significantly elevated Tei index (0.24 ± 0.02 vs. 0.41 ± 0.1, p < 0.001). On the other hand, the regional myocardial velocities and strains of the univentricular heart including the rudimentary RV were significantly reduced (p < 0.001). Among patients, there was a significant correlation between the Tei index of the univentricular ventricle and rudimentary RV strain (r = ?0.66, p = 0.01). The heart rate-corrected intra-univentricular diastolic delay was significantly prolonged among patients when compared to the intra-LV diastolic delay in controls (0.01 ± 0.9 vs. 1 ± 1.1, p = 0.005).Conclusions
Myocardial dysfunctions and intra-univentricular diastolic asynchrony of the univentricular heart in patients after Fontan procedure are evident. The rudimentary RV in patients after Fontan procedure plays an important role in the determination of the global function of the univentricular heart. 相似文献83.
Eman M. Khedr Gharib Fawi Mohammed Abd Allah Abbas Noha Abo El-Fetoh Ahmed F. Zaki Ayman Gamea 《Neurological research》2013,35(8):663-668
Background and purpose: There have been few studies to estimate the prevalence of Bell’s palsy (BP) in Arab countries. A community-based study was conducted to estimate the prevalence, incidence rates, precipitating factors, and outcome of BP in Qena Governorate, Egypt.Subjects and methods: A door-to-door survey was carried out, with random sampling of 10 districts, involving 9303 inhabitants, 51.1% males and 48.9% females. Seventeen subjects were positive in screening questionnaire and referred to Qena University hospital and were subjected to a full clinical examination, House Brackmann’s Facial grading system.Results: In a total population of 9303 individuals, 15 cases were confirmed as having BP giving a prevalence rate (PR) 161/105 for all ages 95%CI (80–243). It was slightly but not significantly higher among women and the rural community. The incidence rate of BP was 107/105. The highest age-specific rate was 40–49 years age. The most frequent precipitating factors for an episode of BP were exposure to air draft in 40%, physical stress (13.3%), and upper respiratory tract infection (13.3%). Moreover, 46.7% had predisposing risk factors, DM and hypertension in 33.3%. Sixty percent of cases had complication and poor outcome.Conclusion: The overall prevalence and incidence rates of BP in Qena governorate were high. This could be related to the variation in day and night temperature in our community and the susceptibility to air draft exposure during the night. The high frequency of poor outcome among studied cases suggests that better local guidelines should be implemented to recognize and treat BP. 相似文献
84.
Silver nanoparticles were in situ prepared on the surface of linen fabric coated by graphene oxide (GO). In the meantime, the reduction of silver nitrate on the GO-coated fabric led to the synthesis of reduced graphene oxide on the fabric. Two kinds of substrate (cotton and linen) were used. Both RGO/Ag and Ag/GO nanocomposites were added on cotton and linen fabrics through a conventional “pad–dry–cure” method. The chemistry and morphology of the coated surfaces were extensively characterized using Fourier-transformed infrared spectroscopy, energy-dispersive X-ray spectroscopy, and scanning electron microscopy. Resistivity measurements were used for assessing the conductivity. The UV protection properties and the photocatalytic activity of the coated fabrics against methylene blue dye were also investigated. The antibacterial activity was studied against Gram-positive S. aureus and B. subtilis and Gram-negative bacterial strains E. coli and P. aeruginosa by determining the zone of inhibition using the agar diffusion method. Methicillin-resistant Staphylococcus aureus (MRSA) has been responsible for many serious hospital infections worldwide. The fabrics showed superior antibacterial activity and successfully hindered the growth of pathogenic bacterial strains. This outcome suggested that both the RGO/Ag and Ag/GO nanocomposites-coated fabrics could be potentially applied in biomaterials and biomedical fields.Silver nanoparticles were in situ prepared on the surface of linen fabric coated by graphene oxide (GO). 相似文献
85.
Omar Ahmad Hassanien Rasha T. Abouelkheir Mohamed Ibrahim Abou El-Ghar Manal Ezzat Badawy Samir Abdel-hakim El Gamal Mohamed Abd El-Hamid 《Journal l'Association canadienne des radiologistes》2019,70(3):254-263
PurposeThe aim of study is to assess the role of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and correlation with tumour angiogenesis in evaluation of urinary bladder cancer.Material and MethodsThe study included 81 patients with recent presumed diagnosis of bladder tumour or who came for follow up after management of histopathologically proven bladder cancer. All had DCE-MRI with time–signal intensity curve. The radiologic results then correlated with the histopathologic results using both haematoxylin and eosin stain and immuno-histochemical staining for localization and evaluation of CD34 immunoreactivity as a detector for the microvessel density (MVD) and tumour angiogenesis.ResultsSeventy-one cases were pathologically proven to be malignant: 41 cases (58%) showed type III time–signal intensity curve (descending); 22 cases (31%) showed type II (plateau); and 8 cases (11%) showed type I (ascending) curve. The sensitivity of DCE-MRI in stage T1 bladder tumour was 80%; in stage T2, it was (90.9%); and in stage T3, it was (96.9%). Overall accuracy of DCE-MRI in tumour staging was 89.5% and P = .001 (significant). Values more than the cutoff value = 76.13 MVD are cystitis with sensitivity (90%), specificity (91%), and P value is .001, which is statistically highly significant.ConclusionThere is a strong positive association between DCE-MRI (staging and washout slope of the time–signal intensity curve) with histopathologic grade, tumour stage, and MVD in bladder cancer. So, DCE-MRI can be used as reliable technique in preoperative predictions of tumour behavior and affect the planning of antiangiogenetic therapy. 相似文献
86.
87.
Hydroxychloroquine augments early virological response to pegylated interferon plus ribavirin in genotype‐4 chronic hepatitis C patients
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Gouda Kamel Helal Magdy Abdelmawgoud Gad Mohamed Fahmy Abd‐Ellah Mahmoud Saied Eid 《Journal of medical virology》2016,88(12):2170-2178
88.
Letter: concordance of SVR4 and SVR12 following direct‐acting anti‐viral treatment in Egypt
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89.
Saini R Abd Razak NH Ab Rahman S Samsudin AR 《Journal (Canadian Dental Association)》2007,73(2):175-178
Chondrosarcomas are malignant tumours of cartilaginous origin. They range from a well-differentiated growth resembling a benign cartilage tumour to a high-grade malignancy with aggressive local behaviour and the potential to metastasize. Only 5% to 10% of chondrosarcomas are known to occur in the head and neck region. A case of chondrosarcoma of the anterior region of the mandible is presented, along with a review of the relevant literature. 相似文献
90.
Handan Bardak Abdülhadi Cihangir Uğuz Yavuz Bardak 《Cutaneous and ocular toxicology》2018,37(2):112-120
Purpose: To investigate the possible protective effects of melatonin and memantine (MMT) against 2-ethylpyridine (2-EP)-induced oxidative stress and mitochondrial dysfunction in human RPE (ARPE-19) cells in vitro.Materials and methods: The ARPE-19 cells were divided into seven groups. Oxidative stress was triggered by incubating the ARPE-19 cells with 30?μM of 2-EP for 24?h. Then, 200?μM of melatonin was administered over three days and 20?μM of MMT over six hours prior to the experiment. The effects of melatonin and MMT on the intracellular calcium release mechanism, reactive oxygen species production, caspase-3 and caspase-9 activities, as well as vascular endothelial growth factor levels were measured.Results: Melatonin and MMT were found to significantly decrease apoptosis levels. The intracellular calcium release was regulated by both melatonin and MMT. Further, melatonin and MMT significantly decreased both caspase-3 and caspase-9 activities, as well as pro-caspase and poly(ADP-ribose) polymerase expression, in ARPE-19 cells. Moreover, melatonin significantly increased the protective effect of MMT. The combination of melatonin and MMT significantly decreased 2-EP-induced oxidative toxicity and apoptosis by inhibiting the intracellular reactive oxygen species production and mitochondrial depolarization levels.Conclusions: These notable findings are the first to demonstrate the synergistic protective effects of melatonin and MMT against 2-EP-induced oxidative stress in ARPE-19 cells. 相似文献