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A fibrinolytic enzyme obtained from B. subtilis was purified, using DEAE-cellulose column chromatography, and gel filtration on Sephadex G-100. The preparation was homogeneous as tested by gel filtration on Sephadex G-200, and disc electrophoresis. The molecular weight of this enzyme was 29.400 estimated by gel filtration on Sephadex G-100. The optimum pH for enzyme activity was 7.2. Copper ions significantly increased enzyme activity, while Zn++ and Mn++ caused marked inhibition. 相似文献
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Hamed NA Hano AF Raouf HA Gamal M Eissa M 《The Egyptian journal of immunology / Egyptian Association of Immunologists》2003,10(1):17-26
The immune system can effectively eliminate hepatitis C virus (HCV) in 15 % of acute hepatitis cases. It is assumed that certain HLA-DR alleles present HCV epitopes more effectively to CD4 helper T cells than do others resulting in vigorous proliferative response to these epitopes and probably HCV recovery. So, we aimed at investigating the frequency of HLA-DRB1*0101 and DRB1*0301 alleles in child and adult haemophilics and in HCV positive hepatocellular carcinoma (HCC) patients in a trial to predict patients who require early therapeutic intervention. We also evaluated interleukin (IL)-12 levels in these patients since IL-12 induces interferon (IFN)-gamma production. This study was conducted on 50 antiHIV negative male patients subdivided into: 25 HCV negative haemophilics (group I), 10 HCV positive haemophilics (group II) and 15 HCV positive HCC (group III). Fifteen healthy persons of matched age and free of HCV and HIV infections were chosen as controls (group IV). All patients and controls were subjected to thorough history taking and clinical examination, routine and diagnostic investigations, viral markers, DRB1*0101 and DRB1*0301 amplification by polymerase chain reaction and plasma IL-12 quantitation by enzyme linked immunosorbent assay (ELISA). The frequencies of DRB1*0101 and DRB1*0301 were 20% and 30% respectively in HCV positive haemophilics and 13.3% and 40%, respectively in HCC. IL-12 levels were significantly lower in HCC cases than in HCV positive haemophilics. Among the haemophilics, IL-12 levels were non-significantly higher in children than in adults and were associated with the given number of blood product bags. DRB1*0101 and DRB1*0301 may have a role in HCV clearance and persistence in Egyptian patients with haemophilia and HCC. Low IL-12 levels encountered in HCV positive haemophilics suggest its relation to immunopathogenesis and outcome of HCV infection. 相似文献
4.
Sanaa?K.?BardaweelEmail author Amal?A.?Akour Maria-Vanessa?Z.?Kilani 《BMC women's health》2015,15(1):117
Background
Studies exploring the knowledge, attitude and patterns of OCs use among women in Jordan are lacking. The aim of this study was to assess knowledge, attitude, and patterns of oral contraceptives (OCs) utilization among women in Jordan.Methods
A face-to-face questionnaire inquiring demographic information and issues related to knowledge and use of OCs was completed by women (n?=?1571), who have had used OCs at least once in their lifetime. A model was created to assess the effects of knowledge, attitude and previous experience on the patterns of OCs utilization.Results
Jordanian women exhibited positive attitudes towards OCs efficacy and safety. This positive attitude was approvingly associated with the patterns of use. However, only half of participating women reported that they knew how to use OCs. About 60 % of women received recommendations for OCs use from a physician. Moreover, women’s knowledge about OCs mechanism of action was obtained namely from physician (29.9 %). Side effects were reported in 75.1 % of participating women. Reported side effects were headache (41.2 %), mood swings (35.5 %), irritability (33.5 %) and weight gain (28.7 %). Interestingly, the occurrence of side effects was the main reason for OCs discontinuation.Conclusion
The study showed that women who have positive attitude toward OCs tend to utilize them more appropriately. However, there is still need for educational programs to enhance knowledge about OCs utilization in Jordan.5.
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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
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Ibrahim H. Eissa Ahmed M. Metwaly Amany Belal Ahmed B.M. Mehany Rezk R. Ayyad Khaled El‐Adl Hazem A. Mahdy Mohammed S. Taghour Kamal M.A. El‐Gamal Mohamad E. El‐Sawah Souad A. Elmetwally Mostafa. A. Elhendawy Mohamed M. Radwan Mahmoud A. ElSohly 《Archiv der Pharmazie》2019,352(11)
In continuation of our previous work on the design and synthesis of topoisomerase II (Topo II) inhibitors and DNA intercalators, a new series of quinoxaline derivatives were designed and synthesized. The synthesized compounds were evaluated for their cytotoxic activities against a panel of three cancer cell lines (Hep G‐2, Hep‐2, and Caco‐2). Compounds 18b, 19b, 23, 25b , and 26 showed strong potencies against all tested cell lines with IC50 values ranging from 0.26 ± 0.1 to 2.91 ± 0.1 µM, comparable with those of doxorubicin (IC50 values ranging from 0.65 ± 0.1 to 0.81 ± 0.1 µM). The most active compounds were further evaluated for their Topo II inhibitory activities and DNA intercalating affinities. Compounds 19b and 19c exhibited high activities against Topo II (IC50 = 0.97 ± 0.1 and 1.10 ± 0.1 µM, respectively) and bound the DNA at concentrations of 43.51 ± 2.0 and 49.11 ± 1.8 µM, respectively, whereas compound 28b exhibited a significant affinity to bind the DNA with an IC50 value of 37.06 ± 1.8 µM. Moreover, apoptosis and cell‐cycle tests of the most promising compound 19b were carried out. It was found that 19b can significantly induce apoptosis in Hep G‐2 cells. It has revealed cell‐cycle arrest at the G2/M phase. Moreover, compound 19b downregulated the Bcl‐2 levels, indicating its potential to enhance apoptosis. Furthermore, molecular docking studies were carried out against the DNA–Topo II complex to examine the binding patterns of the synthesized compounds. 相似文献
10.
Ghanim H Monte SV Sia CL Abuaysheh S Green K Caruana JA Dandona P 《The Journal of clinical endocrinology and metabolism》2012,97(7):E1197-E1201