Effects of metal surface grinding at the porcelain try-in stage of fixed dental prostheses

Halil İbrahim Kılınç,Bülent Kesim,Hasan Önder Gümüş,Mehmet Dinçel,Selçuk Erkaya 대한치과보철학회 2014 The Journal of Advanced Prosthodontics Vol.6 No.4

PURPOSE. This study was to evaluate the effect of grinding of the inner metal surface during the porcelain try-in stage on metal-porcelain bonding considering the maximum temperature and the vibration of samples. MATERIALS AND METHODS. Ninety-one square prism-shaped (1 × 1 × 1.5 mm) nickel-chrome cast frameworks 0.3 mm thick were prepared. Porcelain was applied on two opposite outer axial surfaces of the frameworks. The grinding was performed from the opposite axial sides of the inner metal surfaces with a low-speed handpiece with two types of burs (diamond, tungsten-carbide) under three grinding forces (3.5 N, 7 N, 14 N) and at two durations (5 seconds, 10 seconds). The shear bond strength (SBS) test was performed with universal testing machine. Statistical analyzes were performed at 5% significance level. RESULTS. The samples subjected to grinding under 3.5 N showed higher SBS values than those exposed to grinding under 7 N and 14 N (P<.05). SBS values of none of the groups differed from those of the control group (P>.05). The types of bur (P=.965) and the duration (P=.679) did not affect the SBS values. On the other hand, type of bur, force applied, and duration of the grinding affected the maximum temperatures of the samples, whereas the maximum vibration was affected only by the type of bur (P<.05). CONCLUSION. Grinding the inner metal surface did not affect the metalporcelain bond strength. Although the grinding affected the maximum temperature and the vibration values of the samples, these did not influence the bonding strength.

Synthesis and Quartemization of 6-(Substitutedamino)-Purines with Antitumor Activity Screening

El-Bayouki, Khairy-A.M.,Basyouni, Wahid-M.,El-Din, S.M.,Habeeb, A.G. The Pharmaceutical Society of Korea 1994 Archives of Pharmacal Research Vol.17 No.2

Reaction of c-chloro-9-benzyl-8-(methylthio)purine 3 with primary amines afforoded, the comesponding 6-(substitutedamino)purines 4a-g. The latter products when methylated with methyl iodide yielded smoothly $N^3$-methyl purinium iodide salts 5a-f rather than the probable $N^1\;and\;N^7$-derivatives. 9-Benzyl-3-methyl-6-(methylmino)-8-(methylthio)purine 8 was obtained upon treating the purinium iodide 5a with alkali. Most of the synthesized compounds were screened for their antitumor activity.

Testing unknown age classes of life distributions based on TTT-transform

El-Din, M.M. Mohie,Abu-Youssef, S.E.,Ali, Nahed S.A. The Korean Reliability Society 2013 International Journal of Reliability and Applicati Vol.14 No.1

A nonparametric procedure for testing exponentially against used better than aged in expectation (UBAE) class of life distributions is presented. We construct a test statistics based on scaled total time on test (TTT)-transformation, to test exponentiality against UBAE class of life distributions. The distribution of the statistic is investigated via simulation. Practical applications of the proposed test are presented.

Does anaesthesia in mothers during delivery affect bilirubin levels in their neonates?

El-Kabbany, Zeinab A,Toaima, Nadin N,Toaima, Tamer N,EL-Din, Mona Y Gamal The Korean Pediatric Society 2017 Clinical and Experimental Pediatrics (CEP) Vol.60 No.12

Purpose: This study aimed to assess whether different anesthetic techniques and oxytocin use applied during delivery affect transcutaneous bilirubin levels during the first 24 hours in neonates. Methods: A total of 1,044 neonates delivered by either caesarian section (C/S) or normal vaginal delivery (NVD) were included in the study. They were classified into 5 groups as follows: group 1: born by C/S using general anesthesia, group 2: C/S using spinal anaesthesia, group 3: C/S using general anesthesia after failed spinal block, group 4: by NVD without anesthesia, and group 5: oxytocin-induced vaginal delivery without anesthesia. Transcutaneous total bilirubin levels (TBLs) were measured during the first 24 hours and on the fifth and eighth days of life and the levels in different groups were compared. Results: The TBLs were significantly higher in neonates delivered by C/S using general anesthesia rather than spinal anesthesia (P<0.001), and both groups had higher levels than those born by NVD without anesthesia ($P{\leq}0.001$). However, the group receiving general anesthesia after failed spinal block was found to have the highest bilirubin level. Moreover, TBLs were significantly higher with the use of oxytocin ($P{\leq}0.001$). Conclusions: C/S and general anesthesia adversely affect the bilirubin levels in neonates, and the use of oxytocin during vaginal delivery also increases TBLs in neonates.

Synthesis and broad-spectrum antiproliferative activity of diarylamides and diarylureas possessing 1,3,4-oxadiazole derivatives

Gamal El-Din, M.M.,El-Gamal, M.I.,Abdel-Maksoud, M.S.,Yoo, K.H.,Oh, C.H. Pergamon Press 2015 Bioorganic & medicinal chemistry letters Vol.25 No.8

A series of diarylamides and diarylureas possessing 1,3,4-oxadiazole scaffold was designed and synthesized. Their in vitro antiproliferative activities were tested against a panel of 58 cell lines of nine different cancer types at the NCI, and compared with Sorafenib as a reference compound. Most of the compounds showed strong and broad-spectrum antiproliferative activities. The diarylurea compound 2g possessing 4-chloro-3-(trifluoromethyl)phenyl terminal moiety showed the highest mean % inhibition value of about 100% over the 58-cell line panel at 10μM concentration. Also compounds 2h, 2l, 2m exhibited mean % inhibition over 90% at 10μM concentration. The IC<SUB>50</SUB> value of compound 2b over SNB-75 CNS cancer cell line was 0.65μM. Compound 2h also exerted submicromolar IC<SUB>50</SUB> values of 0.67, 0.80, and 0.87μM against PC-3 prostate cancer cell line, HCT-116 colon cancer cell line, and ACHN renal cancer cell line, respectively. Compound 2h showed comparable efficacy to Sorafenib.

Semen parameters on the intracytoplasmic sperm injection day: Predictive values and cutoff thresholds of success

Alaa El din-Abdel Aal Moubasher,Emad Abdelrehim Taha,Ehab Mohamed Elnashar,Ahmed Abdel Aal Abdel Maged,Asmaa Mohamed Zahran,Heba Hassan Sayed,Hisham Diab Gaber 대한생식의학회 2021 Clinical and Experimental Reproductive Medicine Vol.48 No.1

Objective: This study was conducted to investigate the relationship of semen parameters in samples used for intracytoplasmic sperm injection (ICSI) with fertilization and pregnancy rates in infertile couples.Methods: In this prospective study of Infertile couples with male factor infertility that had undergone ICSI, fractions of the same semen samples obtained for microinjection (to ensure the best predictability) were evaluated to determine the semen parameters and sperm DNA fragmentation index (DFI) on the day of oocyte recovery.Results: In total, 120 couples completed the study and were subdivided into fertilized (n=87) and non-fertilized couples (n=33). The fertilized couples were further classified into pregnant (n=48) and non-pregnant (n=39) couples. Compared to non-fertilized and non-pregnant couples, fertilized and pregnant couples showed statistically significantly higher sperm viability and percentage of normal sperm morphology, as well as significantly lower sperm DFI values. A receiver operating characteristic curve analysis of data from the 120 ICSI cycles showed that sperm viability, normal sperm morphology percentages, and sperm DFI were significant prognostic indicators of fertilization at cutoff values of 40%, 7%, and 46%, respectively. A sperm DFI of 46% showed sensitivity and specificity of 95% and 90%, respectively, for predicting fertilization, and no clinical pregnancies occurred in couples with a sperm DFI above 46%.Conclusion: Semen parameters from the ICSI day sample, especially sperm viability, normal morphology, and DFI, had an impact on fertilization and pregnancy outcomes in ICSI cycles.

Seismic performance of pile-founded fixed jacket platforms with chevron braces

Nour El-Din, Mohamed,Kim, Jinkoo Taylor & Francis 2015 STRUCTURE AND INFRASTRUCTURE ENGINEERING Vol.11 No.6

Predicting the Impact of Subsurface heterogeneous Hydraulic Conductivity on the Stochastic Behavior of Well Draw down in a Confined Aquifer Using Artificial Neural Networks

Alaa El-Din Abdin,Mostafa A. M. Abdeen 대한기계학회 2005 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.19 No.8

Groundwater flow and behavior have to be investigated based on heterogeneous subsurface formation since the homogeneity assumption of this formation is not valid. Over the past twenty years, stochastic approach and Monte Carlo technique have been utilized very efficiently to understand the groundwater flow behavior. However, these technique require lots of computational and numerical efforts according to the various researchers' comments. Therefore, utilizing new techniques with much less computational efforts such as Artificial Neural Network (ANN) in the prediction of the stochastic behavior for the groundwater based on heterogeneous subsurface formation is highly appreciated. The current paper introduces the ANN technique to investigate and predict the stochastic behavior of a well draw down in a confined aquifer based on subsurface heterogeneous hydraulic conductivity. Several ANN models are developed in this research to prediet the unsteady two dimensional well draw down and its stochastic characteristics in a confined aquifer. The results of this study showed that ANN method with less computational efforts was very efficiently capable of simulating and predicting the stochastic behavior of the well draw down resulted from the continuous constant pumping in the middle of a confined aquifer with subsurface heterogeneous hydraulic conductivity.

Protective action of polysaccharides from Laurencia papillose (Rhodophyta) against imidacloprid induced genotoxicity and oxidative stress in male albino rats

Hossam El Din H. Abdelhafez,Amr A AbdAllah,Mostafa M Afify,Naglaa F Mahmoud,Jiangfeng Guo,Soha A Murad,Eman A Ibrahim 환경독성보건학회 2022 환경독성보건학회지 Vol.37 No.2

Imidacloprid (IMI), the main component of neonicotinoid insecticides, promotes oxidative stress and genotoxicity in mammals. The aim of this experiment is to assess oxidative stress in liver cells and genotoxicity of erythrocytes for rats exposed to sub-lethal doses of IMI and the protective effects for Rhodophyta as antioxidant material versus imidacloprid. A total of 30 adult male albino rats (average body weight, 190-200 g) were divided into six groups (n=5) as follows: group 1 served as the control, group 2 received 200 mg/kg red algae, group 3 received 45 mg/kg IMI (high-dose group), group 4 received 22.5 mg/kg IMI (low-dose group), group 5 received 200 mg/kg red algae +45 mg/kg IMI, and group 6 received 200 mg/kg red algae +22.5 mg/kg IMI. After 28 d of treatment, the antioxidant activity of the crude extract of red algae was assessed in terms of free radical scavenging activity and found to be higher in TCA (75.57%) followed by DPPH (50.08%) at concentration 100 μg extract and a significant increase in lipid peroxidation and reductions in glutathione were observed in liver cells were intoxicated with high and low doses of IMI. Moreover decreases in catalase and glutathione peroxidase parameters in same previous groups which indicated oxidative stress. In addition significant increases in micronucleus frequency (MN) in the bone marrow of the rats as a genotoxicity marker which indicated DNA damage in erythrocytes cells with alterations in the histopathology of liver cells were also noted such as necrosis, inflammatory cells, infiltration, and necrobiotic changes. Whereas Rhodophyta succeeded in alleviation the oxidative damage and genotoxicity induced by the insecticide. In conclusion, IMI demonstrates hazardous effects, such as alterations in antioxidant status and mutagenicity of erythrocytes and polysaccharides from Rhodophyta has good antioxidant activity in vivo model systems against imidacloprid.

Insecticidal and developmental inhibitory properties of monoterpenes on Culex pipiens L. (Diptera: Culicidae)

Hossam El-Din M. Zahran,Samir A.M. Abdelgaleil 한국응용곤충학회 2011 Journal of Asia-Pacific Entomology Vol.14 No.1

Twelve monoterpenes were evaluated for larvicidal and adulticidal activities towards Culex pipiens. Geraniol and cuminaldehyde were the most toxic monoterpenes to larvae, with LC_50 values of 38.6 and 38.9 mg/l after 24 h of treatment, respectively, whereas cuminaldehyde was the most potent compound after 48 h of treatment, followed by geraniol and thymol. In fumigant toxicity experiments, (R)-carvone and geraniol were the most toxic monoterpenes against the adults at all three tested concentrations and after both 24 and 48 h. When tested at sublethal concentrations (0.5 LC_50), (R)-carvone, (S)-limonene and cuminaldehyde decreased hatchability, pupation and adult emergence and induced high larval mortality. Our results suggest that geraniol, cuminaldehyde and (R)-carvone are promising toxicants against Culex pipiens and could be useful in the search for new natural insecticides.