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1.
Influence of phenolics on the sensitivity of free and immobilized bioluminescent Acinetobacter bacterium 总被引:1,自引:0,他引:1
Zaki S Abd-El-Haleem D Abulhamd A Elbery H Abuelreesh G 《Microbiological research》2008,163(3):277-285
In this work, the constructed bioluminescent Acinetobacter strain DF4/PUTK2 was employed to assess the toxicity of phenolic compounds and the 5 min EC50 values were calculated. The results of the DF4/PUTK2 assay were further evaluated by comparing with the results of the Vibrio fischeri luminescence inhibition assay. To develop a bioassay system appropriate to be used in continuous toxicity testing, strain DF4/PUTK2 was subjected for immobilization in microtiter plates into the matrices Ca-alginate, polyacrylamide, agar and agarose. After a choice of materials was tried, Ca-alginate was selected as the most suitable candidate material. Because, it could be stored at least 8 weeks at 4 °C, during which the ability of the bioreporter DF4/PUTK2 to detect the toxicity of phenolics was maintained. However, the stability of the bioluminescence for DF4/PUTK2 cells immobilized into agarose and agar was significantly less than that of cells stored in alginate suspensions. This study recommended that luxCDABE-marked Acinetobacter strain DF4/PUTK2 could be employed to assay the ecotoxicity of environmental samples contaminated with phenols. The host strain of the bioreporter DF4/PUTK2 is Acinetobacter strain DF4. It is known that members of the genus Acinetobacter are widespread in nature and also involved in biodegradation, leaching and removal of several organic and inorganic man-made hazardous wastes. 相似文献
2.
Ahmed Ezz El-Arab Abd Al-Aliem Eman A.E. Badr Elsayed Ibrahem El-Shayeb Ahmed Megahed Ahmed Taman Abd El-naser Abd El-atty Gadallah 《Biochemistry and Biophysics Reports》2021
BackgroundTo date, the cause of inflammatory bowel disease (IBD) remains a mystery. A balance between cell proliferation and apoptosis maintains intestinal tissue homeostasis. Dissociation-induced myosin-actin contraction results in stem cell apoptosis. This study aiming to evaluate the influence of the myosin heavy chain 9 (MYH9) gene single nucleotide polymorphisms (SNPs) on inflammatory bowel disease.Subjectsand methods: The study carried on eighty patients with IBD and seventy controls. All participants subjected to history taking, thorough physical examination, colonoscopy and laboratory investigations. Genotyping performed for rs4821480 and rs3752462 by SNP assay real-time PCR methods.ResultsOn analyzing rs3752462 CT and TT genotypes were significantly more frequent in IBD patients as compared to controls with 4.6 fold increase in the risk of IBD. While on analyzing rs4821480, The TG and GG genotypes have significant increased distribution among the IBD patients as compared to the controls with 5.3 fold increase in the risk of IBD and higher prevalence of GG genotype in patients with low hemoglobin level and higher BMI.ConclusionThe rs3752462 T allele and rs4821480 G allele of MYH9 are associated with more susceptibility to IBD. 相似文献
3.
The present study was aimed to evaluate the effect of olive (Olea europaea) leaves extract on streptozotocin (STZ)-induced diabetic male rats. The experimental rats were divided into six groups. Rats of the first group were served as normal controls. Rats of the second group were diabetic control. The third and fourth groups were diabetic rats, treated with olive leaves extract at low and high doses respectively. The fifth and sixth groups were non diabetic rats, subjected to olive leaves extract at the same doses given to the third and fourth groups respectively. The minimum of body weigh gain was noted in diabetic rats of the second group. the levels of serum glucose, insulin, total protein, albumin, triglycerides, cholesterol, low density lipoprotein cholesterol (LDL-C), very low density lipoprotein cholesterol (VLDL-C), creatine kinase (CK), lactate dehydrogenase (LDH) and malondialdehyde (MDA) were significantly increased, while the levels of high density lipoprotein cholesterol (HDL-C), superoxide dismutase, (SOD) glutathione (GSH) and catalase (CAT) were statistically decreased in diabetic rats of the second group. The levels of liver insulin receptor substrate 1 (IRS1) and insulin receptor A (IRA) were significantly declined in diabetic rats of the second group. The diabetic pancreatic sections from diabetic rats of the second group showed several histopathological changes. Administration of low and high doses of olive leaves extract improved the observed physiological, molecular and histopathological alterations. Collectively, the obtained results confirmed that the protective effects of olive leaves extract are attributed to the antioxidant activities of olive leaves extract and its active constituents. 相似文献
4.
Charlotte Vandenberghe Franois Frelchoux Fawziah Gadallah Alexandre Buttler 《植被学杂志》2006,17(4):481-488
Question: What is the effect of gap size on the seedling emergence, growth and survival of four common tree species in wooded pastures? Location: A pasture in the Jura mountains, Switzerland. Methods: Seeds were sown in a complete three‐way factorial design with eight blocks in May 2003. Each block consisted of a competition treatment (four gap sizes including zero) and a mowing treatment (mown and unmown). Emergence, survival and total biomass of tree seedlings of three species (Picea abies, Acer pseudoplatanus and Fagus sylvatica) were measured. A fourth species (Abies alba) failed to germinate. Results: Gaps had a positive influence on the early stages of tree development for all species. Larger gaps favoured growth and survival more than small gaps. Seedling growth was higher when vegetation around the openings was mown. Mowing the vegetation at gap size zero enhanced both growth and survival compared to unmown vegetation. Mown gaps larger than zero had increased seedling desiccation but decreased seedling predation. Species showed similar trends in their emergence and growth responses to gap size and mowing treatments but for Picea emergence rate was higher and survivorship was lower than for Acer and Fagus. Conclusions: Gap size does matter for tree seedling success but even in more favourable large gaps only a small percentage of seedlings emerged and survived. The effects of gaps on tree seedling establishment are complex as a result of interactions between biotic and abiotic changes caused by gaps. 相似文献
5.
Ahmed Mostafa Soliman Neveen Samy Gadallah Hathal Mohammed Al Dhafer 《Zoology in the Middle East.》2017,63(1):58-62
In the present study, the genus Gynecaptera Skorikov, 1935 is recorded from the Arabian Peninsula for the first time, with a nocturnal new species, G. arabica Soliman &; Gadallah, which has been collected from the Riyadh region in Saudi Arabia and which is described and illustrated.http://www.zoobank.org/urn:lsid:zoobank.org:pub:F7ACB779-3750-4DC6-B29B-B7F290E7C7B4 相似文献
6.
The morphology of the antennal sensilla of both male and female Habrobracon hebetor (Say) (Hymenoptera: Braconidae) is described using Scanning Electron Microscopy complemented with Transmission Electron Microscopy.
Five types of innervated sensilla as well as uninnervated microtrichia were found. These types are: sensilla trichodea; s.
chaetica; s. basiconica; s. coeloconica; and s. placodea. No differences in shape, basic structure, and types of antennal
sensilla were found between males and females. The types of sensilla of both sexes of H. hebetor were compared with what has been described in other parasitic Hymenoptera, and their putative functions are discussed with
reference to their morphology, distribution and ultrastructure. 相似文献
7.
Effects of shoot and root supplementation with silicon on the response of Zea mays L. plants to matric water potential (Ψm) and oxygen deficiency (waterlogging) stresses were studied. The soil water limitation (Ψm) and oxygen deprivation significantly reduced shoot dry weight, chlorophyll (Chl) content, ascorbic acid content, as well as leaf relative water content. Both soil drying and waterlogging caused a significant increase in the leaf membrane injury by heat (51°C) and dehydration (40% PEG) stresses. The levels of lipid peroxidation (POL) and hydrogen peroxide (H2O2) content were increased by excess soil drying and oxygen deficiency. Supplementary silicon at 1.0 mM significantly increased Chl content and improved water status. Concentrations of H2O2, MDA, and proline and leaf membrane injury were significantly reduced by Si application. The reverse helds true for ascorbic acid. The results of this study indicate that application of silicon might improve growth attributes, effectively mitigate the adverse effect of drought and waterlogging, and increase tolerance of maize plants. The silicon-induced improvement of drought and anoxia tolerance was associated with the increase in oxidative defense abilities. 相似文献
8.
9.
Short-Term Effects of Cattle Browsing on Tree Sapling Growth in Mountain Wooded Pastures 总被引:2,自引:0,他引:2
Charlotte Vandenberghe François Freléchoux Marie-Agnès Moravie Fawziah Gadallah Alexandre Buttler 《Plant Ecology》2007,188(2):253-264
Browsing by livestock has been identified as an important factor preventing tree regeneration in wooded pastures. Two field
experiments were performed to investigate the effects of cattle browsing on tree sapling growth in a mountain-wooded pasture.
Two size classes (ca. 12–17 cm and 41–59 cm) of each of 4 species (Picea abies, Abies alba, Acer pseudoplatanus and Fagus sylvatica) were exposed to zero, low and high grazing intensities. We measured the proportion of saplings browsed and the effect of
browsing on growth. A mowing treatment within the zero grazing intensity treatment showed no significant effect on sapling
growth. One percent of the large saplings but 25% of the small saplings escaped browsing. Saplings were better protected when
surrounded by taller vegetation. The proportion of saplings browsed was not significantly different among species although
evergreen tree saplings lost a larger proportion of biomass than deciduous species when browsed. Under grazing, average current-year
shoot production and total aboveground biomass of all species were significantly reduced. Browsing effects tended to be smaller
at the lower grazing intensity. Because the deciduous species were least reduced in aboveground growth, especially under the
low grazing intensity, we conclude that at least in short-term, deciduous species are less affected by cattle browsing. 相似文献
10.
The effect of exogenous kinetin application on the growth and some physiological processes of Lupinus termis plants growing in metal containing solutions with excess concentrations of Cu and Zn ion were studied. Generally, plants growing in these solutions had a lower chlorophyll (Chl.) content, leaf relative water content (RWC) and produced less biomass than the control plants. Proline content was higher in metal-treated plants than in untreated controls. Chromatography of cell-free-extracts of roots and shoots indicated three main protein peaks with molecular weights about 170, 75--70 and 5--45 kDa. These peaks were coincident with Cu or Zn maxima. Addition of kinetin reduced the decline in Chl. content in metal-treated plants, improved water status of the plants and enhanced growth of the shoots and roots. The Cu or Zn content expressed on a per mg protein basis was raised when kinetin was applied to the growing shoots. Kinetin (Kin), Cu and Zn, singly and in the presence of kinetin (Cu × Kin and Zn × Kin), significantly affected the parameters tested. Only the effects of Cu × Kin and Zn × Kin interactions on shoot fresh weight and Cu × Kin on root length were statistically insignificant. Based on the calculated coefficient of determination (
2) the roles of Cu and Zn in affecting Chl. content and growth were dominant in comparison to kinetin. Kinetin effect was dominant for root length and proline content, but the role of the interaction was subdominant. The results of this study indicate that kinetin can alleviate the harmful effects of Cu and Zn on the growth of lupin plants through stimulation of Cu and Zn incorporation into metal-binding proteins. 相似文献