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61.
Azza Hanif Harisna Rizky Nurdiansyah Putri Hawa Syaifie Dwi Wahyu Nugroho Kurniawan Eko Saputro Chandra Dwi Prakoso Nurul Taufiqu Rochman Nurwenda Novan Maulana Alfian Noviyanto Etik Mardliyati 《Biochemistry and Biophysics Reports》2021
Docking analysis of propolis's natural compound was successfully performed against SARS-CoV-2 main protease (Mpro) and spike protein subunit 2 (S2). Initially, the propolis's protein was screened using chromatography analysis and successfully identified 22 compounds in the propolis. Four compounds were further investigated, i.e., neoblavaisoflavone, methylophiopogonone A, 3′-Methoxydaidzin, and genistin. The binding affinity of 3′-Methoxydaidzin was ?7.7 kcal/mol, which is similar to nelfinavir (control), while the others were ?7.6 kcal/mol. However, we found the key residue of Glu A:166 in the methylophiopogonone A and genistin, even though the predicted binding energy slightly higher than nelfinavir. In contrast, the predicted binding affinity of neoblavaisoflavone, methylophiopogonone A, 3′-Methoxydaidzin, and genistin against S2 were ?8.1, ?8.2, ?8.3, and ?8.3 kcal/mol, respectively, which is far below of the control (pravastatin, ?7.3 kcal/mol). Instead of conventional hydrogen bonding, the π bonding influenced the binding affinity against S2. The results reveal that this is the first report about methylophiopogonone A, 3′-Methoxydaidzin, and genistin as candidates for anti-viral agents. Those compounds can then be further explored and used as a parent backbone molecule to develop a new supplementation for preventing SARS-CoV-2 infections during COVID-19 outbreaks. 相似文献
62.
Background/Objective
Bladder cancer is the commonest type of malignant tumors as a result of schistosomaisis which is a major healthy problem in many subtropical developing countries. The aim of this study is to comparatively elucidate the underlying biochemical tumor markers in schistosomal bladder cancer versus non-schistosomal bladder cancer when compared to normal healthy ones. 相似文献63.
Azza Hegazi Ehsan Hassan Kamal A. El-Atrebi Hala T. El-Bassyouni 《Journal of Genetic Engineering and Biotechnology》2011,9(1):73-76
The present study was carried out to assess the predictive value and expression of the proliferative activity of Ki-67 and the expression of p53 protein in Helicobacter pylori associated chronic gastritis. This study comprised archival blocks from 20 dyspeptic patients who at National Hepatology and Tropical Medicine Research Institute underwent a diagnostic oesophago-gastroduodenoscopy with multiple gastric antral endoscopic biopsies for histological examination. The blocks were cut at 5 nM thicknesses, stained by hematoxylin and eosin to score the inflammatory grade and subjected to Giemsa stain to assess H. pylori infection, and then immune–histochemical method was done to determine protein P53 and Ki-67. The obtained results indicated that there was no significant association between the expression of Ki67 and P53 in the studied cases. There was no significant association between Ki67 and P53 in the presence of intestinal atrophy, intestinal metaplasia, intestinal activity and intestinal inflammation. While, there was significant association between Ki67 and P53 in intestinal dysplasia, P = 0.015, 0.025, respectively. It could be concluded that the significant association of the proliferative marker Ki-67 and apoptotic marker p53 protein with intestinal dysplasia may be one of the main predictive values in the development of gastric carcinoma in patients with gastritis secondary to H. pylori infection. 相似文献
64.
Propolis, a resinous substance collected by Apis mellifera bees from various plant sources and mixed with secreted beeswax, is a multifunctional material used by bees in the construction, maintenance, and protection of their hives. The collected propolis sample, from High Egypt, was dark-green with olive-odor. The minimal inhibition concentration (MIC) of propolis-ethanolic-extract, against Aeromonas hydrophila, was 80 μg Propolis-ethanolic-extract and crude propolis (1%) were added to artificial basal diet with (30% crude protein) to evaluate their efficacy on the fish growth-performance, immunostimulation and resistance to A. hydrophila. Two hundred and twenty-five Oreochromis niloticus (8 ± 0.45 g/fish) were divided into three equal treatments (T) of triplet replicates. The fish of T1 were fed on basal diet (control). The fish of T2 were given the basal diet, containing propolis-ethanolic-extract. The fish of T3 were given the basal diet containing crude propolis for 28 day. The fish were intraperitoneally challenged by A. hydrophila (0.2 × 107 cells ml−1) at the end of the feeding period and kept for 15 more days.The best growth rate and feed conversion ratio were obtained with T2. The increase in the average daily gain, specific growth rate and feed efficiency ratio were highly significances in T2 followed by T3 when compared with the control group. The HCT-level and monocyte-counts were increased (T2). No significant change, in the large lymphocytic-count was found among the three treatments (28–27–28%), while the neutrophil-count was significantly decreased (7%) with T2 and increased (13.11%) with the control. A significant increase in serum lysozyme and serum bactericidal activities was found with T2. The RLP against A. hydrophila was high with T2 and T3.The propolis-ethanolic-extract enhanced the growth, immunity and resistance of O. niloticus against A. hydrophila more than the crude propolis. 相似文献
65.
Relationships between wetland ecotones and inshore water quality in the Ugandan coast of Lake Victoria 总被引:1,自引:0,他引:1
Andrés Cózar Nadia Bergamino Stefania Mazzuoli Nicholas Azza Luca Bracchini Arduino M. Dattilo Steven A. Loiselle 《Wetlands Ecology and Management》2007,15(6):499-507
Much of the lake shore in Lake Victoria is covered by extensive wetlands, often dominated by dense papyrus stands that extend
out over the lake waters. These wetlands, their extension and management play a role in the physical, chemical and biological
conditions of the inshore waters. Continuous transects along 180 km of shoreline together with spatial grids of sampling sites
in eight bays were performed in the Ugandan inshore waters in order to analyze the relationships between the wetland characteristics
and water quality. Measurements of extension of the wetland ecotones, water temperature (T), pH, Secchi disk depth (SD), dissolved
oxygen (DO), total nitrogen (TN), total phosphorous (TP), dissolved inorganic nitrogen (DIN), soluble reactive phosphorus
(SRP) and chlorophyll-a (CHL) were made in each sampling area. Data of T, pH and DO collected during the transects showed that the water characteristics
of the bays differ from the open shoreline. Moreover, the magnitude of these physical–chemical differences is strongly conditioned
by the dimension of the bordering wetlands. Bays with extensive wetlands ecotones were characterized by cooler, more acidic
and poorly oxygenated waters. TN : TP ratios and especially DIN : SRP ratios decreased with the wetland presence along the
coastline, showing a higher probability of N limitation in the inshore waters where large wetlands are present. Results point
to denitrification processes in the wetland ecotones as the cause of this trend. The distribution of CHL was found to be highest
in the presence of two significant point loading sources: a river (in Katonga Bay) and a major population centre (Kampala,
in Murchison Bay). The reduction of external P loading is shown as an important step in the management of the eutrophication
process of Lake Victoria inshore waters. 相似文献
66.
Azza A. Tawfik Mohamed F. Mohamed 《In vitro cellular & developmental biology. Plant》2007,43(1):21-27
Nodular meristematic callus was induced on the basal cut surface of apical shoot explants of salvia cultured on Murashige
and Skoog (MS) medium supplemented with 4.5, 13.5, or 22.5 μM thidiazuron (TDZ). Cultures were incubated in the dark for 1 wk
and then transferred to light conditions for 4 wk. A higher percentage of explants developing callus was observed on medium
containing either 4.5 or 13.5 μM TDZ, although explants on 4.5 μM developed larger calluses. The callus was maintained on
medium containing 4.5 μM TDZ and 0.45 mM ascorbic acid. Shoot differentiation, after each of three successive maintenance
passages, was induced from callus grown on medium containing either 4.4 or 8.8 μM benzyladenine (BA). A greater number of
shoots were harvested from callus differentiated on BA (4.4 or 8.8 μM) medium with 0.45 mM ascorbic acid added. Shoots developed
roots on MS medium supplemented with 4.9 μM of indole-3-butyric acid. The addition of ascorbic acid to the shoot differentiation
medium enhanced rooting, number of roots per shoot, and survival rate. Approximately 75% in vitro plantlets were acclimatized to ex vitro conditions. Histological investigations confirmed both adventitious meristem initiation during the callus induction phase,
and subsequent organogenic shoot development on the differentiation medium. The novel protocol for the meristematic callus
induction and plant regeneration in this study may be useful for biotechnological applications for salvia improvement via
genetic transformation or mutagenesis and in vitro propagation approaches. 相似文献
67.
Azza Mohamed Noor El-Deen Hoda Mohamed Abdel Halim Shata Mohamed Abdel Fattah Farid 《Annals of microbiology》2014,64(2):627-637
Eleven different Aspergillus strains were evaluated for their ability to produce β-glucosidase using sugar cane bagasse as a sole carbon source under solid state fermentation (SSF). The most potent strains, A. niger NRC 7 (674.6 U/g ds) and A. oryzae NRRL 447 (83 U/g ds), were used in a mixed culture to enhance β-glucosidase production by co-culturing under SSF. In mixed culture, β-glucosidase of the two strains (814 U/g ds) was nearly 1.2- and 9.8-fold than that of monocultures of A. niger NRC 7A and A. oryzae NRRL 447, respectively. Optimization of the culture parameters, initial pH value, moisture content, inoculum size and ratios of the two strains. and incubation time exhibited a significant increase in β-glucosidase production (1,893 U/g ds) than before optimization. Single feeding with citrate-phosphate buffer, succinate buffer, casein. and soybean flour individually after the third day of the fermentation time and controlling the moisture content at 90 % (w/w) induced β-glucosidase production. Maximum enzyme production increased up to 2.1-fold compared to 2,188 U/g ds during normal batch culture. Among nitrogen sources, soybean flour gave the highest β-glucosidase (4,578 U/g ds). while urea reduced β-glucosidase production (1,693 U/g ds). However, the combination of buffers with soybean flour through two fed cycles resulted in a decrease of the enzyme than single fed with buffers or soybean flour alone. 相似文献
68.
Trebec DP Chandra D Gramoun A Li K Heersche JN Manolson MF 《Journal of cellular biochemistry》2007,101(1):205-220
Large osteoclasts (>or=10 nuclei) predominate at sites of pathological bone resorption. We hypothesized this was related to increased resorptive activity of large osteoclasts and have demonstrated previously that larger osteoclasts are 8-fold more likely to be resorbing than small osteoclasts (2-5 nuclei). Here we ask whether these differences in resorptive activity can be explained by differences in expression of factors involved in osteoclast signaling, fusion, attachment, and matrix degradation. Authentic rabbit osteoclasts and osteoclasts derived from RAW264.7 cells showed similar increases in c-fms expression (1.7- to 1.8-fold) in large osteoclasts suggesting that RAW cells are a viable system for further analysis. We found 2- to 4.5-fold increases in the expression of the integrins alpha(v) and beta(3), the proteases proMMP9, matMMP9 and pro-cathepsinK, and in activating receptors RANK, IL-1R1, and TNFR1 in large osteoclasts. In contrast, small osteoclasts had higher expression of the fusion protein SIRPalpha1 and the decoy receptor IL-1R2. The higher expression of activation receptors and lower expression of IL-1R2 in large osteoclasts suggest they are hyperresponsive to extracellular factors. This is supported by the observation that the resorptive activity in large osteoclasts was more responsive to IL-1beta, and that this increased activity was inhibited by the IL-1 receptor antagonist, IL-1ra. This increased responsiveness of large osteoclasts to IL-1 may, in part, explain the pathological bone loss noted in inflammatory diseases. The heterogeneity in receptor expression and the differential response to cytokines and their antagonists could prove useful for selective inhibition of large osteoclasts actively engaged in pathological bone loss. 相似文献
69.
Van Eyken E Van Camp G Hendrickx JJ Demeester K Vandevelde A Azza JB Van de Heyning P Van Laer L 《Genetic testing》2007,11(3):231-234
GJB2 (Gap Junction protein beta type 2; Connexin 26, CX26) is known for its contribution to nonsyndromic recessive deafness (NSRD). One particular mutation, 35delG, a deletion of one guanine from a stretch of six leading to a frame shift early in the gene, has a high prevalence in populations from European descent. 35delG testing therefore has become a standard test in genetic diagnostic laboratories. Most of the currently available methods for the detection of 35delG are relatively time consuming, and not suited for high-throughput diagnostic testing. Within this paper we present a real-time PCR genotyping assay based on melting curve analysis, requiring only a single preparation step before the actual analysis. The assay was optimized on a panel of 48 samples with known 35delG genotypes and subsequently tested using a large Belgian population (N = 460) with unknown 35delG status. For the latter set of samples, real-time PCR results were validated with SNAPShot, an assay used in our laboratory for diagnostic purposes. The real-time PCR genotyping method has proven to be highly reliable, rapid, cost-effective, and suitable for high-throughput screening. We believe that this genetic test for 35delG will find widespread applications in the DNA diagnostic field. 相似文献