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      • KCI등재

        Characterization of alanyl aminopeptidase from insecticide resistant and susceptible strains of Musca domestica L.

        Sohail AHMED1,Waqas WAKIL,David MANTLE,Richard M. WILKINS,권용정 한국곤충학회 2008 Entomological Research Vol.38 No.3

        To investigate the high activity of intracellular proteases in insecticide resistant strains of Musca domestica L., purification by anion-exchange chromatography and gel filtration of one of the enzymes, alanyl aminopeptidase (Ala AP), in three strains of Musca domestica was carried out. The fractions collected by gel filtration of soluble homogenates of the three strains (571ab, 17bb and Cooper) showed a single peak of Ala AP activity. Partially purified Ala AP of the three strains showed high activity at pH 7.5. The presence or absence of Ca2+ in the assay medium did not produce any difference in activity of Ala AP in the 571ab and Cooper strains, but there was a significant difference in the 17bb strain. The activity of Ala AP in all three strains was essentially unaltered in the presence of inhibitors of serine (PMSF), cysteine (E-64) proteases and carboxypeptidases (pepstatin). Ala AP hydrolyzed alanine amino methylcoumarin (Ala-AMC) maximally, followed by phenyl alanine amino methylcoumarin (Phe-AMC), leucyl amino methylcoumarin (Leu-AMC) and ornithine amino methylcoumarin (Orn-AMC). Ala AP from the three strains showed differential activity towards various substrates. The comparison of alanyl aminopeptidase’'s activity from different sources is discussed.

      • KCI등재후보

        A modified trans-anconeus approach to facilitate fixation of a posterior radial head fracture: a cadaveric feasibility study

        Ahmed Mohamed Desouky(Ahmed Mohamed Desouky ),Ahmed Naeem Atiyya(Ahmed Naeem Atiyya ),Mohamed Elbishbishi(Mohamed Elbishbishi ),Marwa Mohamed El Sawy(Marwa Mohamed El Sawy ) 대한해부학회 2023 Anatomy & Cell Biology Vol.56 No.1

        Fixation of radial head fracture with minimally invasive posterior approach remains a significant challenge. The aim of this study was to determine the feasibility of trans-anconeus posterior elbow approach and to observe lateral ulnar collateral ligament (LUCL) in extended elbows. This cadaveric study was performed in twenty upper limbs of fresh fixed adult male cadavers. An oblique incision was made in the middle segment of anconeus until the lateral ligament complex and the joint capsule had been revealed. A deep dissection was explored to observe the anatomical relationship of the LUCL to the anconeus. Measurements of the LUCL were recorded while the elbow was fully extended. The mean distance between the edge of the radial head and the proximal insertion of the LUCL was 13.3 mm (11.5–16.2 mm); the mean distance between the edge of the radial head and the distal insertion of the LUCL was 20.9 mm (19.2–23.4 mm); the distance between the edge of the radial head and the distal edge of the annular ligament was 11.2 mm (8.22–11.7 mm). By estimate correlation of the previous measurements, the direct and accessible way to expose the posterolateral articular capsule of the elbow joint was through a window in medial 2/3 of the middle segment of anconeus muscle. These trans-anconeus approach is useful. It provides good visualization, facilitates applying the implants, and lessens the risk of radial nerve injury. Awareness of the anatomy is mandatory to avoid injury of LUCL.

      • Poster Session : PS 0590 ; Critical Care Medicine ; Early CT Scan to Detect Anastomotic Leak: Is It Worth It?

        ( Ahmed Ahmed ),( Ayan Banerjea ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

        Background: Early diagnosis of anastomotic leakage after colorectal surgery and adequate treatment is crucial to reduce both morbidity and mortality. Computed tomography(CT) scanning is the diagnostic investigation of preference, but its role is questionable in the early postoperative days. The accuracy of CT scanning in the early postoperative period within the fi rst few days after surgery may even be lower when compared to a CT scan more than a week after surgery. Methods: 185 patients underwent 1 or more bowel anastomosis during the period of 6 months. A prospective data sheet was updated regularly with post op morbidity and mortality. The type of anastomosis, timing of postoperative CT scan, diagnosis of leakage and accuracy of the CT scan in detecting it were all recorded. Results: 54 patients (29%) had CT scans post operatively, of whom 48 happened during the same admission with a mean time of 5±3 days postoperatively.A total of 9 patients had their fi rst CT scan onday 3 or earlier postoperatively with one leak detected on that. The mean time for diagnosing a leak was 14±8 days. Conclusions: Timely and correct diagnosis and treatment of anastomotic leakage after bowel surgery remains to be a major challenge.Clinical decision remains of utmost importance in the individual patient and should therefore not depend on one specifi c clinical or additional diagnostic factor.

      • KCI등재

        Fundamental Output Voltage Enhancement of Half-Bridge Voltage Source Inverter with Low DC-link Capacitance

        Ahmed Elserougi,Ahmed Massoud,Shehab Ahmed 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.1

        Conventionally, in order to reduce the ac components of the dc-link capacitors of the two-level Half-Bridge Voltage Source Inverter (HB-VSI), high dc-link capacitances are required. This necessitates the employment of short-lifetime and bulky electrolytic capacitors. In this paper, an analysis for the performance of low dc-link capacitances-based HB-VSI is presented to elucidate its ability to generate an enhanced fundamental output voltage magnitude without increasing the voltage rating of the involved switches. This feature is constrained by the load displacement factor. The introduced enhancement is due to the ac components of the capacitors’ voltages. The presented approach can be employed for multi-phase systems through using multi single-phase HB-VSI(s). Mathematical analysis of the proposed approach is presented in this paper. To ensure a successful operation of the proposed approach, a closed loop current controller is examined. An expression for the critical dc-link capacitance, which is the lowest dc-link capacitance that can be employed for unipolar capacitors’ voltages, is derived. Finally, simulation and experimental results are presented to validate the proposed claims.

      • KCI등재

        Minimally Invasive Transforaminal Lumbar Interbody Fusion for the Surgical Management of Post-Discectomy Syndrome

        Ahmed Bahaa Al Din AlShazli,Ashraf Yassin Amer,Ahmed Maher Sultan,Ahmed Samir Barakat,Wael Koptan,Yasser ElMiligui,Hesham Shaker 대한척추외과학회 2020 Asian Spine Journal Vol.14 No.2

        Study Design: This was a prospective case series of 30 patients with post-discectomy syndrome with an average of 18 months of follow-up (level IV). Purpose: The efficacy of post-discectomy syndrome managed by minimally invasive surgery transforaminal lumbar interbody fusion (MIS-TLIF) was evaluated. Overview of Literature: In post-discectomy syndrome wherein conservative treatment had failed, the best surgical treatment modality still remains controversial. Methods: Patients were functionally assessed using the Visual Analog Scale (VAS) for low back pain (LBP) and leg pain (LP) and Oswestry Disability Index (ODI). Radiological fusion was confirmed with plain X-rays and when indicated with computed tomography scan at 12 months postoperatively. A total of 30 patients with 37 operated at lumbar levels with failed discectomy surgery who met our inclusion criteria were treated with MIS-TLIF. Results: The ODI of all patients showed significant improvement from a mean of 73.78% preoperatively to 16.67% at 1 month and 14.13% at 12 months postoperatively. The preoperative LBP VAS score (mean, 4.37) showed a significant decrease (p<0.001) to 1.90 at 1 month and 1.10 at 12 months. Preoperative LP VAS score of limb pain averaged 7.53 and showed a significant (p<0.001) decrease to 3.47 at 1 month and 1.10 at 12 months. All patients attained radiological fusion at 12 months. Conclusions: MIS-TILF constitutes a valid and effective treatment option for patients with post-discectomy syndrome.

      • KCI등재후보

        The ameliorating role of sofosbuvir and daclatasvir on thioacetamide-induced kidney injury in adult albino rats

        Ahmed H. Moustafa(Ahmed H. Moustafa ),Heba F. Pasha(Heba F. Pasha ),Manar A. Abas(Manar A. Abas ),Adel M. Aboregela(Adel M. Aboregela ) 대한해부학회 2023 Anatomy & Cell Biology Vol.56 No.1

        Thioacetamide (TAA) exposure and hepatitis C virus infection are usually associated with renal dysfunction. Sofosbuvir (SFV) and daclatasvir (DAC) drugs combination has great value in the treatment of hepatitis C. The study aimed to identify the nephrotoxic effects of TAA and to evaluate the ameliorative role of SFV and DAC in this condition. Forty-eight adult male albino rats were divided into eight groups and received saline (control), SFV, DAC, SFV+DAC, TAA, TAA+SFV, TAA+DAC and TAA+SFV+DAC for eight weeks. Kidney and blood samples were retrieved and processed for histological (Hematoxylin and Eosin and Masson’s trichrome), immunohistochemical (α-smooth muscle actin), and biochemical analysis (urea, creatinine, total protein, albumin, malondialdehyde, reduced glutathione, superoxide dismutase, and tumor necrosis factor-α). Examination revealed marked destruction of renal tubules on exposure to TAA with either hypertrophy or atrophy of glomeruli, increase in collagen deposition, and wide expression of α-smooth muscle actin. Also, significant disturbance in kidney functions, oxidative stress markers, and tumor necrosis factor-α. Supplementation with either SFV or DAC produced mild improvement in the tissue and laboratory markers. Moreover, the combination of both drugs greatly refined the pathology induced by TAA at the cellular and laboratory levels. However, there are still significant differences when compared to the control. In conclusion, SFV and DAC combination partially but greatly ameliorated the renal damage induced by TAA which might be enhanced with further supplementations to give new hope for those with nephropathy associated with hepatitis.

      • Bending of axially functionally graded carbon nanotubes reinforced composite nanobeams

        Ahmed Drai,Ahmed Amine Daikh,Mohamed Oujedi Belarbi,Mohammed Sid Ahmed Houari,Benoumer Aour,Amin Hamdi,Mohamed A. Eltaher Techno-Press 2023 Advances in nano research Vol.14 No.3

        This work presents a modified analytical model for the bending behavior of axially functionally graded (AFG) carbon nanotubes reinforced composite (CNTRC) nanobeams. New higher order shear deformation beam theory is exploited to satisfy parabolic variation of shear through thickness direction and zero shears at the bottom and top surfaces.A Modified continuum nonlocal strain gradient theoryis employed to include the microstructure and the geometrical nano-size length scales. The extended rule of the mixture and the molecular dynamics simulations are exploited to evaluate the equivalent mechanical properties of FG-CNTRC beams. Carbon nanotubes reinforcements are distributed axially through the beam length direction with a new power graded function with two parameters. The equilibrium equations are derived with associated nonclassical boundary conditions, and Navier's procedure are used to solve the obtained differential equation and get the response of nanobeam under uniform, linear, or sinusoidal mechanical loadings. Numerical results are carried out to investigate the impact of inhomogeneity parameters, geometrical parameters, loadings type, nonlocal and length scale parameters on deflections and stresses of the AFG CNTRC nanobeams. The proposed model can be used in the design and analysis of MEMS and NEMS systems fabricated from carbon nanotubes reinforced composite nanobeam.

      • KCI등재

        On Separation Axioms in Fuzzifying Bitopological Spaces

        Ahmed Abd El-Monsef Allam,Ahmed Mohammed Zahran,Ahmed Khalf Mousa,Hana Mohsen Binshahnah 한국지능시스템학회 2020 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.20 No.1

        In present paper, we introduce and study the concepts of T₀<SUP>(i;j)</SUP>-, T₁<SUP>(i;j)</SUP> -, T₂<SUP>(i;j)</SUP>(pairwise Hausdorff)-, TR<SUP>(i;j)</SUP> (pairwise regularity)-, TN<SUP>(i;j)</SUP> (pairwise normality)-, R₀<SUP>(i;j)</SUP>-, R₁<SUP>(i;j)</SUP>-, T₃<SUP>(i;j)</SUP> - and T₄<SUP>(i;j)</SUP> - separation axioms in fuzzifying bitopological spaces and study some relations between them. Also we investigate the image of these kinds of fuzzifying bitopological spaces under some types of fuzzy mappings.

      • KCI등재

        A Buck-Boost Converter-Based Bipolar Pulse Generator

        Ahmed A. Elserougi,Ahmed M. Massoud,Shehab Ahmed 전력전자학회 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.6

        This paper presents a buck-boost converter-based bipolar pulse generator, which is able to generate bipolar exponential pulses across a resistive load. The concept of the proposed approach depends on operating the involved buck-boost converters in discontinuous current conduction mode with high-voltage gain and enhanced efficiency. A full design of the pulse generator and its passive components is presented to ensure generating the pulses with the desired specifications (rise time, pulse width, and pulse magnitude) for a given load resistance and input dc voltage. In case of moderate pulsed output voltages (i.e. few of kV), one module of the presented bipolar generator can be employed. While in case of high-voltage pulsed output, multi-module version can be employed, where each module is fed from an isolated dc source and their outputs are connected in series. Simulation models for the proposed approach are built to elucidate their performance in case of one-module as well as multi-module based generator. Finally, a scaled-down prototype for one-module of buck-boost converter-based bipolar pulse generator is implemented to validate the proposed concept.

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