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31.
Samar M. Mahgoub Mohamed R. Shehata Fatma L. Abo El-Ela Ahmed Farghali Amal Zaher Rehab K. Mahmoud 《RSC advances》2020,10(46):27633
Inorganic nano-layered double hydroxide (LDH) materials are used in the catalytic field, and have demonstrated great applicability in the pharmacological fields. In the current study, we report Zn–Al LDH as an adsorbent for levofloxacin (levo). The physical and chemical properties of the prepared material before and after adsorption were monitored using X-ray diffraction, Fourier-transform infrared (FT-IR) spectroscopic analysis, energy dispersive X-ray spectroscopy (EDX), Brunauer–Emmett–Teller (BET) surface area measurements, high-resolution transmission electron microscopy (HRTEM), and field emission scanning electron microscopy (FESEM). Density functional theory (DFT) calculations for levo and its protonated species were studied at the B3LYP/6-311G (d,p) level of theory. The removal percentage of levo was 73.5%. The adsorption isotherm was investigated using nine different models at pH 9, where the obtained correlation coefficients (R2) using the Redlich–Peterson and Toth models were 0.977. The thermodynamic parameters ΔS°, ΔG° and ΔH° were estimated and discussed in detail. Also, to support the adsorption research field, the applicability of the formed waste after the adsorption of levo onto Zn–Al LDH was investigated for medical purposes. The toxicity of levo in both normal and nanocomposite form was studied. Neither toxicological symptoms nor harmless effects were exhibited throughout the in vivo study. The oral anti-inflammatory activity, tested using 6% formalin to produce edema in the footpad, was manifested as a significant increase of 37% in the anti-inflammatory effect of the Zn–Al LDH/levo nanocomposite compared to levo in its normal form.Zn-Al LDH was synthesized using the co-precipitation method, characterized and used as an efficient adsorbent for the removal of levofloxacin. The safety and toxicity of the administered Zn-AL LDH/levo as a safe anti-inflammatory material. 相似文献
32.
Mohamed Abboud Nabil Al-Zaqri Taher Sahlabji Murad Eissa Ahmed T. Mubarak Radhouane Bel-Hadj-Tahar Ali Alsalme Fahad A. Alharthi Amjad Alsyahi Mohamed S. Hamdy 《RSC advances》2020,10(58):35407
Nickel(ii)dibenzotetramethyltetraaza[14]annulene complex (Nitmtaa) was synthetized and immobilized on post amino-functionalized SBA-15 (N-SBA-15) to obtain a stable and reusable nanocatalyst named as Nitmtaa@N-SBA-15. Here (3-aminopropyl)triethoxysilane (APTES) was first grafted on the surface SBA-15, then Nitmtaa was added and coordinated on the silica surface via APTES amine groups. The structure and morphology, and thermal stability of the prepared nanocatalyst was investigated using SEM, HR-TEM, BET, FT-IR, powder XRD, and TGA. HR-TEM and XRD results revealed a high dispersion of Nitmtaa on the SBA-15 surface. The catalytic activity of this nanocatalyst was evaluated in the epoxidation of styrene, under ambient conditions, using meta-chloroperoxybenzoic acid (m-CPBA) as the oxygen donor. This nanocatalyst showed an immediate and quantitative epoxidation of styrene with high turn-over-frequency ∼31.58 s−1. Moreover, the superior catalytic activity and high stability of Nitmtaa@N-SBA-15 could be maintained after four successive cycles. A possible reaction mechanism is also proposed.Immediate and quantitative epoxidation of styrene under ambient conditions catalyzed by new nanocatalyst obtained by immobilizing nickel(ii)dibenzotetramethyltetraaza[14]annulene in amino-functionalized SBA-15. 相似文献
33.
Jay W. Rhee Rory J. Petteys Amjad N. Anaizi Faheem A. Sandhu Jean-Marc Voyadzis 《European spine journal》2015,24(11):2546-2554
34.
Endodontic complications in teeth with vital pulps restored with composite resins: a systematic review
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Composite resin is used extensively for restoration of teeth with vital pulps. Although cell culture studies have disclosed harmful effects on pulpal cells, any untoward clinical effects, manifest as adverse pulpal responses, have yet to be determined. This study comprises a systematic review, designed to address the question of whether the risk of endodontic complications is greater with composite resin restorations than with other restorative materials, such as amalgam. The study methodology involved (i) formulation of the research question, (ii) construction and conduct of an extensive literature search with (iii) interpretation and assessment of the retrieved literature. A search of the medical database PubMed was complemented with a search of the Controlled Trials Register (CENTRAL). The initial search yielded 1043 publications, the abstracts of which were read independently by the authors. After additional searches, 10 studies were included in the review. In all the included studies, the level of evidence was assessed as low. No conclusions could therefore be drawn. The included studies reported few, if any, endodontic complications. Little or no differences emerged between teeth restored with composite resins and those restored with amalgam. To determine whether composite resin restorations of teeth with vital pulps are associated with an increased risk for development of endodontic complications such as apical periodontitis, further evidence is needed, from well‐constructed studies with a large number of participants. 相似文献
35.
Bashir Q Khan H Orlowski RZ Amjad AI Shah N Parmar S Wei W Rondon G Weber DM Wang M Thomas SK Shah JJ Qureshi SR Dinh YT Popat U Anderlini P Hosing C Giralt S Champlin RE Qazilbash MH 《American journal of hematology》2012,87(3):272-276
A total of 149 patients with multiple myeloma (MM) who received allogeneic hematopoietic stem cell transplantation (allo-HCT) with myeloablative (MAC; n = 38) or reduced-intensity conditioning (RIC; n = 110) regimens at MD Anderson Cancer Center were evaluated. Of the total, 120 (81%) patients had relapsed or had refractory disease. Median age of MM patients was 50 (28-70) years with a followup time of 28.5 (3-164) months. The 100-day and 5-year treatment related mortality (TRM) rates were 17% and 47%, respectively. TRM was significantly lower with RIC regimens (13%) vs. 29% for MAC at 100 days (P = 0.012). The cumulative incidence of Grade II-IV acute graft-versus-host disease (GVHD) was 35% and chronic GVHD was 46%. PFS and OS at 5 years were 15% and 21%, respectively. In multivariate analysis, allo-HCT for primary remission consolidation was associated with longer PFS (HR 0.35; 95% CI, 0.18-0.67) and OS (HR 0.29; 95% CI 0.15-0.55), while absence of high-risk cytogenetics was associated with longer PFS only (HR 0.59; 95% CI 0.37-0.95). We observe that TRM has decreased with the use of RIC regimens, and long-term disease control can be expected in a subset of MM patients undergoing allo-HCT. Further studies should be conducted in carefully designed clinical trials in this patient population. 相似文献
36.
Background: Evaluation of right atrial pressure (RAP) provides useful diagnostic, therapeutic, and prognostic information. Aim: To assess the utility of several conventional and tissue Doppler parameters in the estimation of RAP. Methods: Among 50 consecutive patients (median age: 50 years; all in sinus rhythm), invasively measured RAP was simultaneously correlated with pulsed Doppler of tricuspid inflow (peak E and A velocities, E‐wave deceleration time) and pulsed tissue Doppler of lateral tricuspid annulus (peak E’ and A’ velocities, isovolumic relaxation time [IVRT], acceleration time and rate of E’‐wave, deceleration time and rate of E’‐wave). These ratios were calculated: E/A, E’/A’, E/E’, and E/IVRT. Results: The median RAP was 14 mmHg (range 1–27 mmHg) with 29 patients (58%) having an elevated RAP (>10 mmHg). Among all studied Doppler variables, E/E’ ratio showed the strongest correlation with RAP (r = 0.84, P < 0.001) with the following regression equations: RAP = 1.24 + (1.69 × E/E’). The mean difference between Doppler and invasively measured RAP was 0.21 ± 2.6 mmHg. E/ E’ ratio ≥ 4.5 provides 89% sensitivity and 100% specificity for detection of elevated RAP (receiver operating characteristic area 0.95; P < 0.001). Conclusion: Of all echocardiographic variables investigated, tricuspid annular E/E’ ratio is identified as the best index for noninvasive determination of RAP. 相似文献
37.
38.
Wafaa M.A. Farghaly Hamdy N. El-Tallawy Tarek A. Rageh Eman M. Mohamed Nabil A. Metwally Ghaydaa A. Shehata Reda Badry Mohamed A. Abd-Elhamed 《Seizure》2013,22(8):611-616
BackgroundDespite advances in treating epilepsy, uncontrolled epilepsy continues to be a major clinical problem. Therefore, this work aimed to study the epidemiology of uncontrolled epilepsy in Al-Kharga District, New Valley.MethodsThis study was carried out in 3 stages via door-to-door screening of the total population (62,583 persons). All suspected cases of epilepsy were subjected to case ascertainment, conventional ElectroEncephaloGraphy (EEG), and the Stanford-Binet Intelligence Scale. Patients who had been receiving suitable anti-epileptic drugs (AEDs) over the previous 6 months and were having active seizures were considered uncontrolled, according to Ohtsuka et al.23 The patients underwent serum AED level estimation, video EEG monitoring, and brain MRIs. Fifty age- and gender-matched patients with controlled epilepsy were chosen for statistical analysis and compared with true intractable patients.ResultsA total of 437 patients with epilepsy were identified, 30.7% of whom (n = 134/437) were uncontrolled, with a prevalence of 2.1/1000. A total of 52.2% of uncontrolled patients (n = 70/134) were inappropriately treated, while 47.8% (n = 64/134) were compliant with appropriate treatments. Video monitoring EEG of compliant uncontrolled patients demonstrated that 78.1% patients (n = 50/64) had definite epilepsy, while 21.9% (n = 14/64) had psychogenic non-epileptic seizures (PNES). A logistic regression analysis revealed that status epilepticus, focal seizures, and mixed seizure types were risk factors for intractability. 相似文献
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40.
Manfred?OdermattEmail author Karen?Flashman Jim?Khan Amjad?Parvaiz 《Surgery today》2016,46(7):798-806