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Zanaty R. Komy Rabei M. Gabar Ahmed A. Shoriet Rehab M. Mohammed 《World journal of microbiology & biotechnology》2006,22(9):975-982
Summary The ability of Pseudomonas
aeruginosa to accumulate Cd(II) ions from wastewater industries was experimentally investigated and mathematically modelled. From the potentiometric titration and non-ideal competitive analysis (NICA) model, it was found that the biomass contains three acidic sites. The values of proton binding (pK
i
=1.66±3.26×10−3, 1.92±1.63×10−4 and 2.16±3.79×10−4) and binding constant of cadmium metal ions (pK
M1=1.99±2.45×10−3 and pK
M2=1.67±4.08×10−3) on the whole surface of biomass showed that protonated functional groups and biosorption of Cd(II) ions could be attributed to a monodentate binding to one acidic site, mainly the carboxylic group. From the isothermal sorption experimental data and Langmuir model, it was also found that the value of Langmuir equilibrium (pK
f) constant is 2.04±2.1×10−5 suggesting that the carboxyl group is the main active binding site. In addition, results showed that the maximum cadmium capacity (q
max) and affinity of biomass towards cadmium metal ions (b) at pH 5.1 and 20 min were 96.5±0.06 mg/g and 3.40×10−3± 2.10×10−3, respectively. Finally, interfering metal ions such as Pb(II), Cu(II), Cr(III), Zn(II), Fe(II), Mn(II), Ca(II) and Mg(II) inhibited Cd(II) uptake. Comparing the biosorption of Cd(II) by various Pseudomonas isolates from contaminated environment samples (soil and sewage treatment plant) showed that maximum capacities and equilibrium times were different, indicating that there was a discrepancy in the chemical composition between biomasses of different strains. 相似文献
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Lotta Mårtensson Beatriz Díez Ingvild Wartiainen Weiwen Zheng Rehab El-Shehawy Ulla Rasmussen 《Plant and Soil》2009,325(1-2):207-218
The diazotrophic communities in a rice paddy field were characterized by a molecular polyphasic approach including DNA/RNA-DGGE fingerprinting, real time RT-PCR analysis of nifH gene and the measurement of nitrogen fixation activities. The investigation was performed on a diurnal cycle and comparisons were made between bulk and rhizosphere / root soil as well as between fertilized / unfertilized soils. Real time RT-PCR showed no significant difference in the total quantity of nifH expression under the conditions investigated. The functional diversity and dynamics of the nifH gene expressing diazotroph community investigated using RT-PCR-DGGE revealed high diurnal variations, as well as variation between different soil types. Most of the sequence types recovered from the DGGE gels and clone libraries clustered within nifH Cluster I and III (65 different nifH sequences in total). Sequence types most similar to Azoarcus spp., Metylococcus spp., Rhizobium spp., Methylocystis spp., Desulfovibrio spp., Geobacter spp., Chlorobium spp., were abundant and indicate that these species may be responsible for the observed diurnal variation in the diazotrophic community structure in these rice field samples. Previously described diazotrophic cyanobacterial genera in rice fields, such as Nostoc and Cyanothece, were present in the samples but not detectable in RT-PCR assays. 相似文献
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Khalil Rehab G. Abdel-Moneim Adel Yousef Ahmed I. Abdel-Rahman Hanan Zanaty Mohamed I. El-Sayed Amr 《Molecular biology reports》2021,48(7):5421-5433
Molecular Biology Reports - In type 1 diabetes mellitus (T1DM), cytokines have a central role in orchestrating multicellular relations between β-cells and immune cells. This study aims to... 相似文献
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Taiki Sanada Tomomi Sano Yusuke Sotomaru Rehab Alshargabi Yosuke Yamawaki Akiko Yamashita Hiroaki Matsunaga Misaki Iwashita Takanori Shinjo Takashi Kanematsu Tomoichiro Asano Fusanori Nishimura 《Biochemistry and Biophysics Reports》2020
MicroRNA (miRNA) plays an important role in diverse cellular biological processes such as inflammatory response, differentiation and proliferation, and carcinogenesis. miR-146a has been suggested as a negative regulator of the inflammatory reaction. Although, it has been reported as expressed in inflamed adipose and periodontal tissues, however, miR-146a's inhibitory effects against inflammatory response in both the tissues, are not well understood. Therefore, in this study, the inhibitory effects of miR-146a on both adipose and periodontal inflammation, was investigated. In vitro study has revealed that miR-146a transfection into either adipocytes or gingival fibroblasts, has resulted in a reduced cytokine gene expression, observed on co-culturing the cells with macrophages in the presence of lipopolysaccharides (LPS), in comparison to the control miRNA transfected. Similarly, miR-146a transfection into macrophages resulted in a reduced expression of TNF-α gene and protein in response to LPS stimulation. In vivo study revealed that a continuous intravenous miR-146a administration into mice via tail vein, protected the mice from developing high-fat diet-induced obesity and the inflammatory cytokine gene expression was down-regulated in both adipose and periodontal tissues. miR-146a appeared to be induced by macrophage-derived inflammatory signals such as TNF-α by negative feed-back mechanism, and it suppressed inflammatory reaction in both adipose and periodontal tissues. Therefore, miR-146a could be suggested as a potential therapeutic molecule and as a common inflammatory regulator for both obesity-induced diabetes and related periodontal diseases. 相似文献
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The annually reoccurring blooms that characterize the surface waters of the Baltic Sea are dominated by filamentous, heterocystous cyanobacteria such as Nodularia spumigena. In a previous study, we have demonstrated that N. spumigena strain AV1 differentiates heterocysts in the absence of detectable nitrogen fixation activity, an unusual physiological trait that is clearly distinct from other well-studied cyanobacteria. To further analyze the uncoupling between these two processes, we analyzed the gene expression and modification of the nitrogenase enzyme (the enzyme responsible for nitrogen fixation) in N. spumigena AV1, as well as in several other N. spumigena strains. Here, we demonstrate the occurrence of two nifH gene copies in N. spumigena strain AV1, only one of which is located in a complete nifHDK cluster and several NifH protein forms. Furthermore, we demonstrate the occurrence of a DNA rearrangement mechanism acting within the nifH gene copy located in the nifHDK cluster and present only in the strains exhibiting the previously reported uncoupling between heterocyst differentiation and nitrogen fixation processes. These data stress the existence of a distinct and complex regulatory circuit related to nitrogen fixation in this ecologically significant bloom-forming cyanobacterium. 相似文献
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Omega-3 fatty acids are gaining attention as a therapeutic agent of many diseases. Their protective effect in a variety of diseases has been demonstrated. To the best of our knowledge, this is the first study on omega-3 fatty acids related to acute cold-restraint stress (CRS) induced hepatic dysfunction in rats. Forty adult male Sprague–Dawley albino rats were used and classified into: control, omega-3 group, each rat was pretreated with omega-3 fatty acids; CRS group, rats were subjected to acute CRS for 6 hr; and CRS group pretreated with omega-3 fatty acids. Serum was obtained to determine corticosterone (CORT), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and tumor necrosis factor-α (TNF-α) levels. Hepatic malondialdehyde (MDA) and total antioxidant capacity (TAC) levels were measured. Also, liver tissues were taken for histological examination and immunohistochemical assessment of the apoptotic marker, caspase-3. Results showed that pretreatment of stressed rats with omega-3 fatty acids led to significant decrease in hepatic MDA and increase in TAC levels. They reduced serum levels of CORT, ALT, AST, and TNF-α. Also, they improved liver damage and suppressed hepatic caspase-3 expression. In conclusion, pretreatment of stressed rats with omega-3 fatty acids has ameliorated stress-induced liver damage due to their antioxidant, anti-inflammatory, and antiapoptotic effects. So, they can be used to minimize stress complications on the liver. 相似文献
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Sabry Dina Abdelaleem Omayma O. El Amin Ali Amani M. Mohammed Rehab A. Abdel-Hameed Nehal D. Hassouna Amira Khalifa Warda A. 《Molecular biology reports》2019,46(2):2039-2047
Molecular Biology Reports - The effects of epigallocatechin-3-gallate (EGCG) and metformin single treatment have been tested against hepatocellular carcinoma (HCC). This study aimed to assess the... 相似文献
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