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991.
Yacoub A. Yousef Abdelghani Tbakhi Maysa Al-Hussaini Ibrahim AlNawaiseh Ala Saab Amal Afifi Maysa Naji Mona Mohammad Rasha Deebajah Imad Jaradat Iyad Sultan Mustafa Mehyar 《Familial cancer》2018,17(2):261-268
Retinoblastoma (RB) is a childhood cancer developing in the retina due to RB1 pathologic variant. Herein we are evaluating the oncogenic mutations in the RB1 gene and the inheritance patterns of RB in the Jordanian patients. In this prospective study, the peripheral blood of 50 retinoblastoma patients was collected, genomic DNA was extracted, mutations were identified using Quantitative multiplex PCR (QM-PCR), Allele-specific PCR, Next Generation Sequencing analysis, and Sanger sequencing. In this cohort of 50 patients, 20(40%) patients had unilateral RB and 30(60%) were males. Overall, 36(72%) patients had germline disease, 17(47%) of whom had the same RB1 pathologic variant detected in one of the parents (inherited disease). In the bilateral group, all (100%) patients had germline disease; 13(43%) of them had inherited mutation. In the unilateral group, 6(30%) had germline disease, 4(20%) of them had inherited mutation. Nonsense mutation generating a stop codon and producing a truncated non-functional protein was the most frequent detected type of mutations (n = 15/36, 42%). Only one (2%) of the patients had mosaic mutation, and of the 17 inherited cases, 16(94%) had an unaffected carrier parent. In conclusion, in addition to all bilateral RB patients in our cohort, 30% of unilateral cases showed germline mutation. Almost half (47%) of germline cases had inherited disease from affected (6%) parent or unaffected carrier (94%). Therefore molecular screening is critical for the genetic counseling regarding the risk for inherited RB in both unilateral and bilateral cases including those with no family history. 相似文献
992.
Abdulrhman A. Al-Shamry Mai M. Khalaf Hany M. Abd El-Lateef Tarek A. Yousef Gehad G. Mohamed Kariman M. Kamal El-Deen Mohamed Gouda Ahmed M. Abu-Dief 《Materials》2023,16(1)
Through the condensation of isatin (indoline-2, 3-dione) and aniline in a 1:1 ratio, a Schiff base ligand was synthesized and characterized via (1H-NMR, mass, IR, UV-Vis) spectra. Elemental analyses, spectroscopy (1H-NMR, mass, UV-Vis), magnetic susceptibility, molar conductivity, mass spectra, scanning electron microscope (SEM), and thermal analysis have all been used to characterize a series of Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), and Cd(II) metal complexes derived from the titled ligand. The metal-to-ligand ratio is 1:1, according to the analytical data. The Schiff base ligand displayed bidentate behavior with NO coordination sites when it bonded to metal ions, as seen by the IR spectra. The magnetic moment measurement and UV-Vis spectral investigation showed the octahedral geometry of the Cr(III), Fe(III), Co(II), Ni(II), and Zn(II) complexes, whereas they suggested the tetrahedral geometry of the Mn(II), Cu(II), and Cd(II) complexes. The thermal analysis study confirmed the presence of both hydrated and coordinated water molecules in all the compounds, except for the Mn(II) complex, and showed that the complexes decomposed in three or five decomposition steps leaving the corresponding metal oxide as a residue. The ligand and its metal complexes’ antibacterial efficacy were evaluated. The findings showed that the metal complexes had stronger antibacterial properties than the ligand alone. The ligand and its metal complexes’ anticancer properties were also investigated. A DFT investigation is also reported to gather information regarding the electronic features of the ligand and its metal complexes. Finally, drug-likeness and ADME characteristics were also calculated as parameters. 相似文献
993.
N M A White M Mathews G M Yousef A Prizada C Popadiuk J J E Dor�� 《British journal of cancer》2009,101(7):1107-1113
Background:
The human kallikrein-related peptidase family consists of 15 genes. Twelve of these genes are overexpressed in ovarian cancer and may represent potential markers for diagnosis, prognosis, and/or response to treatment. The aim of this study was to determine the prognostic significance of kallikrein-related peptidase 6 (KLK6) and kallikrein-related peptidase 13 (KLK13) in epithelial ovarian cancer by quantifying gene expression levels with tumour pathology and patient survival data.Methods:
Total RNA was isolated from 106 patients diagnosed with primary ovarian cancer, as well as 8 normal ovary controls. Samples were analysed by quantitative real-time PCR for KLK6 and KLK13 expression. Correlation between kallikrein gene expression and clinical characteristics was evaluated with the χ2-test. Survival analysis was performed using Kaplan–Meier and Cox proportional hazards regression models.Results:
Expression levels of both KLK6 and KLK13 mRNA were significantly increased in invasive cancers relative to normal ovaries (P=0.002 and 0.039 respectively). High KLK6 and KLK13 expression was an indicator of poor prognosis, with patients having a shorter recurrence-free survival (P=0.002 and 0.027 respectively). High KLK6 expression was also significantly associated with lower overall survival (P=0.011). When subjected to multivariate analysis, patients with either high KLK6 or KLK13 were 3- and 2.2-fold, respectively, more likely to have a recurrence than patients with low kallikrein expression.Conclusion:
These data show increased mRNA expression of KLK6 and KLK13 in ovarian cancer compared to normal ovarian tissues. High KLK6 or KLK13 expression in primary ovarian tumours can significantly predict prognosis in terms of recurrence-free survival and overall survival. In all, this study shows KLK6 and KLK13 as potential biomarkers and may be therapeutic targets for treatment of ovarian cancer. 相似文献994.
Stroke-free survival and its determinants in patients with symptomatic vertebrobasilar stenosis: a multicenter study 总被引:10,自引:0,他引:10
Qureshi AI Ziai WC Yahia AM Mohammad Y Sen S Agarwal P Zaidat OO Suarez JI Wityk RJ 《Neurosurgery》2003,52(5):1033-9; discussion 1039-40
OBJECTIVE: We sought to determine the long-term stroke-free survival of patients who present with ischemic events related to intracranial vertebrobasilar stenosis. METHODS: A retrospective cohort of patients diagnosed with symptomatic vertebrobasilar stenosis on the basis of magnetic resonance angiography and/or conventional angiography was identified at four academic medical centers. Patients' clinical and follow-up information was obtained through hospitalization records, clinic visits, and telephone interviews. Kaplan-Meier analysis was performed to determine the rate of stroke-free survival for a 5-year period. Cox proportional hazards analysis was performed to determine the effect of demographic and clinical factors on stroke-free survival. RESULTS: A total of 102 patients were included, whose mean age was 64 +/- 12 years. Fifty-five (54%) of the patients were men. The mean follow-up period was 15 +/- 15.9 months (range, 1-60 mo). During the follow-up period, 14 (14%) of the patients experienced recurrent stroke. The overall mortality rate was 21% (n = 21). Stroke-free survival, calculated by using the Kaplan-Meier curve, was 76% at 12 months (95% confidence interval [CI], 66-83%) and 48% at 5 years (95% CI, 27-65%). The risk of recurrent stroke was 10.9 per 100 patient-years, and the rate of recurrent stroke and/or death was 24.2 per 100 patient-years. Cox proportional hazards analysis revealed that increasing age (hazards ratio, 1.05; 95% CI, 1.00-1.09) decreased stroke-free survival. Treatment with either antiplatelet agents or warfarin (hazards ratio, 0.018; 95% CI, 0.003-0.11) had a protective effect on stroke-free survival after adjusting for age, sex, race, hypertension, diabetes mellitus, smoking, hyperlipidemia, and lesion location. CONCLUSION: A low rate of stroke-free survival is observed in patients with symptomatic vertebrobasilar stenosis. Further studies are required to evaluate new medical and endovascular treatment options for this group of patients to improve long-term stroke-free survival. 相似文献
995.
Mohammad Yousef Memar Naser Alizadeh Mojtaba Varshochi 《The journal of maternal-fetal & neonatal medicine》2019,32(1):143-153
Accurate identification of early onset neonatal sepsis (EOS) is challenging. Blood culture has been considered as a gold standard method but the identification of EOS is intricate by a high false-negative results. This review provides an overview of biomarkers as indicators for the diagnosis of EOS. There is an affluence of studies appraising diagnostic indicators in the identification of EOS. Acute-phase reactants, cytokines, and cell surface antigens have been investigated as indicators for EOS, but none of them are presently in routine clinical setting. Despite the promising data for some immunologic biomarkers, present evidence shows that none of them can constantly diagnose 100% of infections. IL-6 is the most potent marker for evaluation of EOS prognosis. Procalciton (PCT) and C-reactive protein (CRP) are appropriate indicators for the detection and monitoring of antibiotics therapy. A panel of sepsis biomarkers along with presently routine tests will make easy earlier identification, appropriate management, and improved outcome may be more efficient than single indicator. 相似文献
996.
Ramesh Paudyal Yonggang Lu Vaios Hatzoglou Andre Moreira Hilda E. Stambuk Jung Hun Oh Kristen M. Cunanan David Aramburu Nunez Yousef Mazaheri Mithat Gonen Alan Ho James A. Fagin Richard J. Wong Ashok Shaha R. Michael Tuttle Amita Shukla‐Dave 《NMR in biomedicine》2020,33(1)
The purpose of this study was to identify the optimal tracer kinetic model from T1‐weighted dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI) data and evaluate whether parameters estimated from the optimal model predict tumor aggressiveness determined from histopathology in patients with papillary thyroid carcinoma (PTC) prior to surgery. In this prospective study, 18 PTC patients underwent pretreatment DCE‐MRI on a 3 T MR scanner prior to thyroidectomy. This study was approved by the institutional review board and informed consent was obtained from all patients. The two‐compartment exchange model, compartmental tissue uptake model, extended Tofts model (ETM) and standard Tofts model were compared on a voxel‐wise basis to determine the optimal model using the corrected Akaike information criterion (AICc) for PTC. The optimal model is the one with the lowest AICc. Statistical analysis included paired and unpaired t‐tests and a one‐way analysis of variance. Bonferroni correction was applied for multiple comparisons. Receiver operating characteristic (ROC) curves were generated from the optimal model parameters to differentiate PTC with and without aggressive features, and AUCs were compared. ETM performed best with the lowest AICc and the highest Akaike weight (0.44) among the four models. ETM was preferred in 44% of all 3419 voxels. The ETM estimates of Ktrans in PTCs with the aggressive feature extrathyroidal extension (ETE) were significantly higher than those without ETE (0.78 ± 0.29 vs. 0.34 ± 0.18 min?1, P = 0.005). From ROC analysis, cut‐off values of Ktrans, ve and vp, which discriminated between PTCs with and without ETE, were determined at 0.45 min?1, 0.28 and 0.014 respectively. The sensitivities and specificities were 86 and 82% (Ktrans), 71 and 82% (ve), and 86 and 55% (vp), respectively. Their respective AUCs were 0.90, 0.71 and 0.71. We conclude that ETM Ktrans has shown potential to classify tumors with and without aggressive ETE in patients with PTC. 相似文献
997.
Khaled Mohammed Al-Jamrah Basheer Abdulgalil Al Nabehi Khaled Abdullah Almoayed Labiba Saeed Anam Yousef S Khader 《JMIR Public Health and Surveillance》2021,7(5)
BackgroundThe Neonatal Tetanus Surveillance System (NTSS) in Yemen was established in 2009 to identify high-risk areas, determine trends, and evaluate elimination activities. Since its launch, the NTSS had never been evaluated.ObjectiveThis study aimed to assess the performance of NTSS and determine its strengths and weaknesses to recommend improvements.MethodsThe US Centers for Disease Control and Prevention (CDC) guidelines were used for evaluating the NTSS. Stakeholders at the central, district, and facility levels were interviewed to rate the attributes of the NTSS. The percentage scores for attributes were ranked as poor (<60%), average (≥60% to <80%) and good (≥80%).ResultsThe overall usefulness score percentage was 38%, which indicates a poor performance. The performance of the NTSS was rated as average on flexibility (score percent: 68%) and acceptability (score percent: 64%) attributes and poor on stability (score percentage: 33%), simplicity (score percentage: 57%), and representativeness (score percentage: 39%) attributes. About 65% of investigation forms were completed within 48 hours of notification date. Data quality was poor, as 41% of the core variables were missing.ConclusionsThe overall performance of the NTSS was poor. Most of the system attributes require improvement, including stability, simplicity, quality of data, and completeness of investigation. To improve the performance of NTSS, the following are recommended: capacity building of staff (focal points), strengthening NTSS through technical support and government funding to ensure its sustainability, establishing electronic investigation forms for improving the system data quality, and expansion of NTSS coverage to include all private health care facilities. 相似文献
998.
Deoxynivalenol (DON) is a type B trichothecene mycotoxin that is commonly detected in cereals and grains world-wide. The low-tolerated levels of this mycotoxin, especially in mono-gastric animals, reflect its bio-potency. The toxicity of DON is conventionally attributed to its ability to inhibit ribosomal protein biosynthesis, but recent advances in molecular tools have elucidated novel mechanisms that further explain DON’s toxicological profile, complementing the diverse symptoms associated with its exposure. This article summarizes the recent findings related to novel mechanisms of DON toxicity as well as how structural modifications to DON alter its potency. In addition, it explores feasible ways of expanding our understating of DON-cellular targets and their roles in DON toxicity, clearance, and detoxification through the utilization of computational biology approaches. 相似文献
999.
1000.
Hanadie Yousef Michael J. Conboy Adam Morgenthaler Christina Schlesinger Lukasz Bugaj Preeti Paliwal Christopher Greer Irina M. Conboy David Schaffer 《Oncotarget》2015,6(14):11959-11978
Stem cell function declines with age largely due to the biochemical imbalances in their tissue niches, and this work demonstrates that aging imposes an elevation in transforming growth factor β (TGF-β) signaling in the neurogenic niche of the hippocampus, analogous to the previously demonstrated changes in the myogenic niche of skeletal muscle with age. Exploring the hypothesis that youthful calibration of key signaling pathways may enhance regeneration of multiple old tissues, we found that systemically attenuating TGF-β signaling with a single drug simultaneously enhanced neurogenesis and muscle regeneration in the same old mice, findings further substantiated via genetic perturbations. At the levels of cellular mechanism, our results establish that the age-specific increase in TGF-β1 in the stem cell niches of aged hippocampus involves microglia and that such an increase is pro-inflammatory both in brain and muscle, as assayed by the elevated expression of β2 microglobulin (B2M), a component of MHC class I molecules. These findings suggest that at high levels typical of aged tissues, TGF-β1 promotes inflammation instead of its canonical role in attenuating immune responses. In agreement with this conclusion, inhibition of TGF-β1 signaling normalized B2M to young levels in both studied tissues. 相似文献