Papers by ahmed ali mostafa
The Journal of Contemporary Dental Practice
Purpose: The goal of this study was to evaluate how different fabrication techniques affected the... more Purpose: The goal of this study was to evaluate how different fabrication techniques affected the marginal accuracy and internal adaptability of poly (ether ether ketone) (PEEK) molar single crowns. Materials and methods: Twenty PEEK crowns were constructed using two different fabrication techniques, and they were divided into two main groups (PEEK-CAD and PEEK-pressed). PEEK-CAD crowns were numbered from 1 to 10. PEEK-pressed crowns were numbered from 11 to 20. Each group had 10 PEEK crowns, and both were constructed over a master die. For internal fit measurements, silicone replica bodies were built and cut into two halves buccolingually. Marginal accuracy was measured using three evenly spaced landmarks along the specimen's cervical circumference on each surface using a Leica L2 APO* microscope. Results: In terms of marginal accuracy, the Press group had a statistically significant greater mean marginal gap value than the computer aideddesigning (CAD) group. While in terms of internal fit, there was no statistically significant difference in internal fit between the CAD and Press groups. At a significance level of two-tailed p-value = 0.21 (p > 0.05). Conclusion: PEEK-CAD crowns demonstrated higher marginal accuracy and nearly similar internal fit when compared to PEEK-pressed crowns. Clinical significance: PEEK material could be used as a substitute for zirconia for a full coverage posterior restoration.
PLOS ONE
The leaves of Azadirachta indica L. and Melia azedarach L., belonging to Meliaceae family, have b... more The leaves of Azadirachta indica L. and Melia azedarach L., belonging to Meliaceae family, have been shown to have medicinal benefits and are extensively employed in traditional folk medicine. Herein, HPLC analysis of the ethyl acetate fraction of the total methanolic extract emphasized the enrichment of both A. indica L., and M. azedarach L. leaves extracts with phenolic and flavonoids composites, respectively. Besides, 4 limonoids and 2 flavonoids were isolated using column chromatography. By assessing the in vitro antiviral activities of both total leaves extracts against Severe Acute Respiratory Syndrome Corona virus 2 (SARS-CoV-2), it was found that A. indica L. and M. azedarach L. have robust anti-SARS-CoV-2 activities at low half-maximal inhibitory concentrations (IC50) of 8.451 and 6.922 μg/mL, respectively. Due to the high safety of A. indica L. and M. azedarach L. extracts with half-maximal cytotoxic concentrations (CC50) of 446.2 and 351.4 μg/ml, respectively, both displa...
Scientific Reports
The persistent evolution of drug-resistant influenza strains represents a global concern. The inn... more The persistent evolution of drug-resistant influenza strains represents a global concern. The innovation of new treatment approaches through drug screening strategies and investigating the antiviral potential of bioactive natural-based chemicals may address the issue. Herein, we screened the anti-influenza efficacy of some biologically active indole and β-carboline (βC) indole alkaloids against two different influenza A viruses (IAV) with varied host range ranges; seasonal influenza A/Egypt/NRC098/2019(H1N1) and avian influenza A/chicken/Egypt/N12640A/2016(H5N1). All compounds were first assessed for their half-maximal cytotoxic concentration (CC50) in MDCK cells and half-maximal inhibitory concentrations (IC50) against influenza A/H5N1. Intriguingly, Strychnine sulfate, Harmalol, Harmane, and Harmaline showed robust anti-H5N1 activities with IC50 values of 11.85, 0.02, 0.023, and 3.42 µg/ml, respectively, as compared to zanamivir and amantadine as control drugs (IC50 = 0.079 µg/ml ...
Iranian Journal of Medical Physics, 2021
Introduction: The study aimed to provide the dose accuracy effects between Anisotropic Analytical... more Introduction: The study aimed to provide the dose accuracy effects between Anisotropic Analytical algorithm (AAA) and the deterministic solver Acuros XB (AXB) that are available on Eclipse TPS (Varian Medical Systems, Palo Alto, CA) treatment planning system (TPS). The different is due to the electron transport difference in case of small fieldsMaterial and methods: For the study non-small cell lung cancer (NSCLC) patient CT scans are used to do retrospective SBRT plans via AAA and recalculated by AXB dose calculation algorithms using Eclipse treatment planning system. The main dosimetric comparison parameters are: Conformity index (CI), Homogeneity Index (HI), Gradient Index (GI), Target mean dose and calculation time. Results: Based on the results, the CI is (1.45±0.55) to (1.85±0.7). The HI are (0.15±0.07) and (0.13±0.08), the Gradient index GI for AAA were (4.8±2.6) and for AXB reaches to (7.4±3.8) and the maximum dose for PTV are differed about 2.3% to 4.5%, mean dose and the c...
Le contrat d'edition constitue le contrat prototype pour les autres contrats d'exploitati... more Le contrat d'edition constitue le contrat prototype pour les autres contrats d'exploitation des droits d'auteur. Ce contrat est bien organise dans certaines legislations telles que les legislations francaise, allemande et espagnole. D'autres, telles que les legislations algerienne, marocaine et tunisienne n'abordent que l'edition graphique et ignorent le fait que l'edition puisse concerner toute oeuvre susceptible d'etre fixee sur un support quelconque. Ce contrat n'est pas organise par la loi en Egypte, comme dans la majorite des pays arabes. Ces derniers regissent ce contrat par les regles du droit commun. Mais elles ne sont pas adaptees a la nature propre de ce contrat et a l'influence du droit moral de l'auteur sur sa conclusion et son execution. Cela apparait a travers l'exigence de consentement personnel de l'auteur, meme incapable pour conclure ce contrat. Elle appariait aussi a travers les principes de l'interpretation ...
British journal of clinical pharmacology, Jan 13, 2018
Massive metformin overdose can cause metabolic acidosis with hyperlactatemia. A 55-year-old femal... more Massive metformin overdose can cause metabolic acidosis with hyperlactatemia. A 55-year-old female presented 5h post multi-drug overdose, including 132 g extended-release metformin. Continuous venovenous haemodiafiltration (CVVHDF) and noradrenaline were commenced due to metabolic acidosis (pH 7.0, lactate 17 mmol/L) and shock. Despite 3 hours of CVVHDF, her acidosis worsened (pH 6.83, lactate 24 mmol/L). Intermittent haemodialysis(IHD) improved acidosis (pH 7.13, lactate 26 mmol/l), but again worsened (pH 6.91, lactate 30 mmol/L) with CVVHDF recommencement. IHD (12 h), CVVHDF (26 h) and vasopressor support for 7 days resulted in survival. Measured metformin concentrations were extremely high with a peak of 292 μg/ml at 8 h post-ingestion. IHD, but not CVVHDF in this case was associated with improvement in metabolic acidosis and hyperlactatemia. Pharmacokinetic analysis of metformin concentrations found a reduced apparent oral clearance (CL/F) of 8.2 L/h and a half-life of approxima...
Clinical cancer research : an official journal of the American Association for Cancer Research, Jan 24, 2016
In addition to their direct cytopathic effects, oncolytic viruses are capable of priming anti-tum... more In addition to their direct cytopathic effects, oncolytic viruses are capable of priming anti-tumor immune responses. However, strategies to enhance the immunotherapeutic potential of these agents are lacking. Here, we investigated the ability of the multi-tyrosine kinase inhibitor and first-line metastatic renal cell carcinoma (RCC) agent, sunitinib, to augment the anti-tumor immune response generated by oncolytic reovirus. In vitro, oncolysis and chemokine production were assessed in a panel of human and murine RCC cell lines following exposure to reovirus, sunitinib or their combination. In vivo, the RENCA syngeneic murine model of RCC was employed to determine therapeutic and tumor-specific immune responses following treatment with reovirus (intra-tumoral), sunitinib or their combination. Parallel investigations employing the KLN205 syngeneic murine model of lung squamous cell carcinoma (NSCLC) were conducted for further validation Results:Reovirus mediated oncolysis and chemoki...
Clinical toxicology (Philadelphia, Pa.), 2016
To describe the cardiovascular toxicity and pharmacokinetics of levetiracetam in overdose. A 43-y... more To describe the cardiovascular toxicity and pharmacokinetics of levetiracetam in overdose. A 43-year-old female presented 8 h post ingestion of 60-80 g of levetiracetam with mild central nervous system depression, bradycardia, hypotension and oliguria. Her cardiovascular toxicity transiently responded to atropine and intravenous fluids. A bedside echocardiogram demonstrated normal left and right ventricular contractility. Despite her cardiovascular toxicity and oliguria, she had normal serial venous lactates and renal function; and made a complete recovery over 48 h. Her levetiracetam concentration was 463 mcg/ml 8 h post ingestion (therapeutic range 10-40 mcg/ml) and her concentration-time data best fitted a one-compartment model with first-order input and an elimination half-life of 10.4 h. Levetiracetam in large ingestions appears to cause bradycardia and hypotension that is potentially responsive to atropine and intravenous fluids. Based on a normal echocardiogram, the mechanism...
The Journal of general virology, Jan 7, 2016
Influenza vaccine strains (IVS) contain the hemagglutinin (HA) and neuraminidase (NA) genome segm... more Influenza vaccine strains (IVS) contain the hemagglutinin (HA) and neuraminidase (NA) genome segments of relevant circulating strains in the genetic background of influenza A/PR/8/1934 virus (PR8). Previous work has shown that the nature of the PB1 segment may be a limiting factor for the efficient production of IVS. Here, we show that the PB1 segment (PB1Gi) from the 2009 pandemic influenza A virus (IAV) A/Giessen/06/2009 (Gi wt, H1N1pdm) may help to resolve (some of) these limitations. We produced a set of recombinant PR8-derived viruses that contained (i) the HA and NA segments from representative IAV strains (H3N2, H5N1, H7N9, H9N2), (ii) the PB1 segment from PR8 or Gi wt, respectively, and (iii) the remaining five genome segments from PR8. Viruses containing the PB1Gi segment, together with the heterologous HA/NA segments and five PR8 segments (5+2+1), replicated to higher titers compared to their 6+2 counterparts containing six PR8 segments and the equivalent heterologous HA/N...
A new anchor is developed to delay complete delamination in RC beams externally strengthened with... more A new anchor is developed to delay complete delamination in RC beams externally strengthened with FRP laminate. The anchor is made by cutting NEFMAC grids in the form of π shape. The anchor legs are 90 mm long and the spacing between the legs is either 50 or 100 mm. The anchor spine and legs have the same 10 x 10 mm rectangular cross section. Nine full scale RC beams, 3.0 m long, 250 mm wide and 400 mm deep, were strengthened with CFRP laminate in conjunction with the anchor. The main test parameters were the type and amount of FRP laminate and the presence/absence of the anchor. Test results showed that beams with the anchor had generally 5-10% higher delamination load and reached higher deflection at failure than the companion beams without anchors. Although complete separation of the external reinforcement from the concrete was not observed in any of the beams with anchors, there was substantial slip at one end of the FRP laminate. A significant outcome was that the anchors were effective in limiting the extent of delamination along the interface, thus indirectly contributing to the flexural stiffness of the beam by limiting the extent of cracking along the span.
A new CFRP anchor is developed and tested using full scale RC T-beams externally strengthened wit... more A new CFRP anchor is developed and tested using full scale RC T-beams externally strengthened with multiple plies of a CFRP sheet. The anchor is made from a carbon fiber tow immersed in an epoxy resin. The anchor head is bonded by epoxy to the surface of the concrete in the vicinity of the FRP sheets and is designed to provide a relatively large surface for resisting interfacial shear stresses. The anchor legs are inserted into pre-drilled holes filled with epoxy adhesive. Four full scale T-beams, each 4880 mm long with span length of 4500 mm, were tested in four point bending. The beams cross-section had a total height of 400 mm and consisted of 500 mm wide by 100 mm thick flange and 250 mm wide web externally strengthened with either 4 or 8 plies of a CFRP sheet. Test results show that the anchor could prevent delamination even in the beams with 8 plies as failure was initiated by the rupture of the FRP. No sign of slippage and/or rupture of the anchors were observed. On the contrary, the companion beams without the anchors prematurely delaminated and they reached only a fraction of their theoretical strength.
Annals of the Rheumatic Diseases, 2015
ObjectiveAxial spondyloarthritis (AxSpA) represents a group of inflammatory axial diseases that s... more ObjectiveAxial spondyloarthritis (AxSpA) represents a group of inflammatory axial diseases that share common clinical and histopathological manifestations. Ankylosing spondylitis (AS) is the best characterised subset of AxSpA, and its genetic basis has been extensively investigated. Given that genome-wide association studies account for only 25% of AS heritability, the objective of this study was to discover rare, highly penetrant genetic variants in AxSpA pathogenesis using a well-characterised, multigenerational family.MethodsHLA-B*27 genotyping and exome sequencing was performed on DNA collected from available family members. Variant frequency was assessed by mining publically available datasets and using fragment analysis of unrelated AxSpA cases and unaffected controls. Gene expression was performed by qPCR, and protein expression was assessed by western blot analysis and immunofluorescence microscopy using patient-derived B-cell lines. Circular dichroism spectroscopy was perfo...
Frontiers in oncology, 2014
The possible link between infection/inflammation/immune activation and a cancer patient's out... more The possible link between infection/inflammation/immune activation and a cancer patient's outcome from both a causative and outcome point of view has long been postulated. Substantial progress in the understanding of tumor-associated antigens/epitopes, immune cellular subpopulations, cytokine pathways/expression, the tumor microenvironment, and the balance between tumor-immune suppression and stimulation have been made over the past decade. This knowledge has heralded a new era of tumor immunotherapy utilizing vaccines, immune checkpoint inhibition, and oncolytic viruses. Despite significant progress in the molecular era now with targeted therapeutics such as EGFR tyrosine kinase inhibitors and ALK fusion protein inhibitors that have significantly improved the outcome of these specific lung cancer subpopulations, the overall 5 year survival for all non-small cell lung cancer (NSCLC) is still <20%. Unlike malignancies such as malignant melanoma, renal cell carcinoma, and neuro...
Experimental Brain Research, 2014
either at a closer (10 cm) or at a farther distance (15 cm) from the home position. We found reac... more either at a closer (10 cm) or at a farther distance (15 cm) from the home position. We found reach adaptation generalized to novel closer and farther targets to the same extent as observed at the trained target distance. In contrast, while changes in felt hand position were significant across the two novel distances, this recalibration was smaller for the novel-far locations compared to the trained location. Given that reach adaptation completely generalized across the novel distances but proprioceptive recalibration generalized to a lesser extent for farther distances, we suggest that proprioceptive recalibration may arise independently of motor adaptation and vice versa.
Journal of Chinese Human Resources Management, 2012
ABSTRACT Purpose ‐ The purpose of this paper is to examine the mediating role of occupational saf... more ABSTRACT Purpose ‐ The purpose of this paper is to examine the mediating role of occupational safety and health (OSH) on the relationship between high performance human resource practices (HPHRP) and organizational performance. Design/methodology/approach ‐ The authors collected data from 227 human resource management professionals in Hong Kong, the People&#39;s Republic of China and used exploratory factor analysis and multiple regression for data analysis. Findings ‐ The results supported the construct validity of the preliminary measure of HPHRP with the inclusion of a measure on OSH. The mediating role of perceived safety climate in the relationship of HPHRP and organizational performance was also confirmed. Research limitations/implications ‐ This research highlights the importance of OSH on HPHRP in Hong Kong organizations. Results explored that HPHRP positively influences organizational performance through the mediator of perceived safety climate. Originality/value ‐ This paper adds value by improving the understanding of the importance of OSH in human resource management in China. It reveals an important path, HRM managers&#39; perceived safety climate, through which HPHRP is transmitted to organizational performance.
Public Administration, 2013
ABSTRACT This article tests the impact of two organization-relevant factors, high commitment huma... more ABSTRACT This article tests the impact of two organization-relevant factors, high commitment human resource practices (HCHRP) and work overload on a component of public service motivation, civic duty and employee outcomes (job satisfaction, affective commitment, and quit intentions). Local government employees in Wales (n=1,755) were used to test our research hypotheses. Results show that both HCHRP and work overload had direct and indirect affects (via civic duty) on employee outcomes. The positive effects of HCHRP on employee outcomes more than compensated for the negative impact of work overload. However, given the modest relations between the organization-relevant factors and civic mindedness, firm efforts should perhaps focus primarily on recruitment and retention campaigns rather than training and socialization strategies.
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Papers by ahmed ali mostafa