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71.
Simultaneous nutrient removal and lipid production from pretreated piggery wastewater by Chlorella vulgaris YSW-04 总被引:1,自引:0,他引:1
Min-Kyu Ji Hyun-Chul Kim Veer Raghavulu Sapireddy Hyun-Shik Yun Reda A. I. Abou-Shanab Jaeyoung Choi Wontae Lee Thomas C. Timmes Inamuddin Byong-Hun Jeon 《Applied microbiology and biotechnology》2013,97(6):2701-2710
The feasibility of using a microalga Chlorella vulgaris YSW-04 was investigated for removal of nutrients from piggery wastewater effluent. The consequent lipid production by the microalga was also identified and quantitatively determined. The wastewater effluent was diluted to different concentrations ranging from 20 to 80 % of the original using either synthetic media or distilled water. The dilution effect on both lipid production and nutrient removal was evaluated, and growth rate of C. vulgaris was also monitored. Dilution of the wastewater effluent improved microalgal growth, lipid productivity, and nutrient removal. The growth rate of C. vulgaris was increased with decreased concentration of piggery wastewater in the culture media regardless of the diluent type. Lipid production was relatively higher when using synthetic media than using distilled water for dilution of wastewater. The composition of fatty acids accumulated in microalgal biomass was dependent upon both dilution ratio and diluent type. The microalga grown on a 20 % concentration of wastewater effluent diluted with distilled water was more promising for generating high-efficient biodiesel compared to the other culture conditions. The highest removal of inorganic nutrients was also achieved at the same dilution condition. Our results revealed the optimal pretreatment condition for the biodegradation of piggery wastewater with microalgae for subsequent production of high-efficient biodiesel. 相似文献
72.
Mary-Ann Davies Sam Phiri Robin Wood Maureen Wellington Vivian Cox Carolyn Bolton-Moore Venessa Timmerman Harry Moultrie James Ndirangu Helena Rabie Karl Technau Janet Giddy Nicola Maxwell Andrew Boulle Olivia Keiser Matthias Egger Brian Eley 《PloS one》2013,8(12)
Background
Since 2005, increasing numbers of children have started antiretroviral therapy (ART) in sub-Saharan Africa and, in recent years, WHO and country treatment guidelines have recommended ART initiation for all infants and very young children, and at higher CD4 thresholds for older children. We examined temporal changes in patient and regimen characteristics at ART start using data from 12 cohorts in 4 countries participating in the IeDEA-SA collaboration.Methodology/Principal Findings
Data from 30,300 ART-naïve children aged <16 years at ART initiation who started therapy between 2005 and 2010 were analysed. We examined changes in median values for continuous variables using the Cuzick''s test for trend over time. We also examined changes in the proportions of patients with particular disease severity characteristics (expressed as a binary variable e.g. WHO Stage III/IV vs I/II) using logistic regression. Between 2005 and 2010 the number of children starting ART each year increased and median age declined from 63 months (2006) to 56 months (2010). Both the proportion of children <1 year and ≥10 years of age increased from 12 to 19% and 18 to 22% respectively. Children had less severe disease at ART initiation in later years with significant declines in the percentage with severe immunosuppression (81 to 63%), WHO Stage III/IV disease (75 to 62%), severe anemia (12 to 7%) and weight-for-age z-score<−3 (31 to 28%). Similar results were seen when restricting to infants with significant declines in the proportion with severe immunodeficiency (98 to 82%) and Stage III/IV disease (81 to 63%). First-line regimen use followed country guidelines.Conclusions/Significance
Between 2005 and 2010 increasing numbers of children have initiated ART with a decline in disease severity at start of therapy. However, even in 2010, a substantial number of infants and children started ART with advanced disease. These results highlight the importance of efforts to improve access to HIV diagnostic testing and ART in children. 相似文献73.
Mariagrazia Antonelli Roberto Reda Maria Pia Aleandri Leonardo Varvaro Gabriele Chilosi 《Journal of Phytopathology》2013,161(7-8):485-496
This study was undertaken to isolate indigenous plant growth‐promoting (PGP) bacteria from solarized soil effective in the biocontrol of Monosporascus cannonballus, the cause of root rot and vine decline of melon, which is one of the most destructive soilborne diseases of this crop worldwide. The screening strategy resulted in the selection of two interesting PGP bacteria as biocontrol candidates against M. cannonballus belonging to the same microbial community. The two bacterial species, identified according to phenotypic, physiological tests and analysis of the 16S rDNA sequence as Bacillus subtilis/amyloliquefaciens (BsCR) and Pseudomonas putida (PpF4), showed PGP traits and in vitro antagonistic activity towards M. cannonballus. Antagonism by BsCR was characterized by a consistent inhibition of the pathogen in vitro growth; PpF4 strongly inhibited the development of perithecia of the pathogen. Under greenhouse conditions, the selected bacteria were tested for their biocontrol activity in the pathosystem melon‐M. cannonballus. BsCR alone and in combination with PpF4 determined a consistent decrease in the disease symptoms. BsCR and the combination of the bacterial strains significantly increased root biomass in both inoculated and un‐inoculated plant. Upon seed treatment with BsCR, the accumulation and isoenzyme induction of peroxidase in roots as biochemical marker for induction of resistance were found, thus indicating that BsCR may reduce the disease severity also by the activation of the plant defence responses. The study highlights the synergistic biocontrol potential of B. subtilis BsCR and P. putida PpF4 in the integrated management of root rot and vine decline of melon caused by M. cannonballus. 相似文献
74.
The detection of cancer biomarkers is as important tool for the diagnosis and prognosis of cancer such as brain cancer. Murine double minute 2 (MDM2) has been widely studied as prognostic marker for brain tumor. Here we describe development of a new sensitive label free impedimetric immunosensor for the detection of MDM2 based on cysteamine self assembled monolayers on a clean polycrystalline Au electrode surface. The amine-modified electrodes were further functionalized with antibody using homobifunctional 1,4-phenylene diisothiocyanate (PDITC) linker. The assembly processes of the immunosensor had been monitored with cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques using Fe(CN)(6)(3-/4-) solution as redox probe. The impedance changes upon binding of MDM2 protein to the sensor surface was utilized for the detection of MDM2. The increase in relative electron-transfer resistance (ΔR/R(0)%) values was linearly proportional to the concentration of tumor marker MDM2 in the wide dynamic range of 1pg/ml-1μg/ml. The limit of detection was 0.29pg/ml in phosphate buffer saline (PBS) and 1.3pg/ml in mouse brain tissue homogenate, respectively. The immunosensor showed a good performance in comparison with ELISA for the analysis of the MDM2 in the cancerous mouse brain tissue homogenates. Moreover, the immunosensor had a good selectivity against epidermal growth factor receptor (EGFR) protein, long-storage stability and reproducibility. It might be become a promising assay for clinical diagnosis and early detection of tumors. 相似文献
75.
Adel M. Kamal El-Dean Geies Ahmed A. Hassanien Reda Abdel-Wadood Fatma K. El-Naeem Eman E. Abd 《Russian Journal of Bioorganic Chemistry》2022,48(4):821-834
Russian Journal of Bioorganic Chemistry - The biological uses of 2,7-naphthyridines have sparked great attention in recent years. For this reason, we synthesized a series of novel... 相似文献
76.
Marwa Matboli Ayman E Shafei Mahmoud A Ali Ahmed M Ashry Kamal M Kamal Mohammed Ali Agag Ibrahim Reda Eman Fathy Tash Marwa Ali 《Journal of cellular biochemistry》2019,120(5):7711-7724
Circular RNAs (circRNAs) are a newly validated type of noncoding RNAs recently found to be deregulated in several human cancers. More accurate and specific noninvasive biomarkers are strongly needed for better diagnosis and prognosis of hepatocellular carcinoma (HCC). We performed a bioinformatics analysis to retrieve a novel panel of circRNAs potentially relevant to HCC. We examined their expression in the sera of 68 patients with HCC, 60 patients with chronic hepatitis C, and 36 healthy controls using quantitative polymerase chain reaction. We examined the performance characteristics of the selected circRNA biomarker panel in comparison with alpha-fetoprotein (AFP). In addition, we performed a survival analysis to correlate between their expression levels and patient survival. The circRNAs hsa_circ _00224 and hsa_circ _00520 showed a strong biomarker potential with relatively high sensitivities and specificities compared with AFP. The combined panel including the three circRNAs showed superior performance characteristics relative to those of AFP. The median follow-up period was 26 months. hsa_circ_00520 expression has been shown to be associated with relapse-free survival (P < 0.005). circRNAs hsa_circ_00156, hsa_circ_000224, and hsa_circ_000520 are novel potential biomarkers of high sensitivity and specificity, which could potentially be used in the diagnosis of HCC. 相似文献
77.
Fuad Ameen Shorouk A. Reda Sahar A. El-Shatoury Emad M. Riad Mohamed E. Enany Abdullah A. Alarfaj 《Saudi Journal of Biological Sciences》2019,26(7):1492-1498
Dairy production is threatened by antibiotic resistant pathogens worldwide, and alternative solutions to treat mastitis are not available. The prevalence of antibiotic resistant strains is not well known in less developed countries. The prevalence of pathogenic bacteria and their resistance to 21 commercial antibiotics were studied in milk samples taken from 122 dairy cows suffering from the symptoms of mastitis in Egypt. The bacterial species were identified with molecular methods, and antibiotic resistance was studied with disc diffusion method. The prevalence of Streptococcus aureus, Escherichia coli and Pseudomonas aeruginosa were 30%, 17% and 3.5%, respectively. Most (90%) of the S. aureus strains showed resistance to penicillin whereas only 10% of the strains were resistant to oxacillin. Nearly half (40%) of E. coli strains showed resistance to streptomycin. Six P. aeruginosa strains showed resistance to several antibiotics, including ceftriaxone, enrofloxacin and levofloxacin. This points out that despite P. aeruginosa was not common, it should be followed up carefully. Potential biocontrol agents against antibiotic resistant mastitis bacteria were searched among 30 endophytic actinobacterial strains derived from wild medicinal plants. Three plants, namely Mentha longifolia, Malva parviflora and Pulicaria undulata were chosen for a more detailed study; their endophytic actinobacteria were used to prepare metabolic extracts. The crude metabolites of the actinobacteria were extracted with ethyl acetate. All metabolic extracts inhibited the growth of S. aureus, methicillin-resistant Staphylococcus aureus (MRSA), E. coli and P. aeruginosa in vitro. The 16S rRNA sequence analysis revealed that the most efficient actinobacterial strains were two Micromonospora sp. and one Actinobacteria bacterium. We conclude that the combination of the metabolites of several endophytic actinobacteria derived from several medicinal plants would be the most efficient against pathogens. Different metabolite cocktails should be studied further in order to develop novel biocontrol agents to treat antibiotic resistant mastitis bacteria in dairy cows. 相似文献
78.
Dominique Hervé Anne Philippi Reda Belbouab Michel Zerah Stéphane Chabrier Sophie Collardeau-Frachon Francoise Bergametti Aurore Essongue Eliane Berrou Valérie Krivosic Christian Sainte-Rose Emmanuel Houdart Frédéric Adam Kareen Billiemaz Marilyne Lebret Sabine Roman Sandrine Passemard Gwenola Boulday Audrey Delaforge Stéphanie Guey Xavier Dray Hugues Chabriat Peter Brouckaert Maryjke Bryckaert Elisabeth Tournier-Lasserve 《American journal of human genetics》2014,94(4):642
79.
80.
Djebbar R Rzigui T Pétriacq P Mauve C Priault P Fresneau C De Paepe M Florez-Sarasa I Benhassaine-Kesri G Streb P Gakière B Cornic G De Paepe R 《Planta》2012,235(3):603-614
To investigate the role of plant mitochondria in drought tolerance, the response to water deprivation was compared between Nicotiana sylvestris wild type (WT) plants and the CMSII respiratory complex I mutant, which has low-efficient respiration and photosynthesis, high levels of amino acids and pyridine nucleotides, and increased antioxidant capacity. We show that the delayed decrease in relative water content after water withholding in CMSII, as compared to WT leaves, is due to a lower stomatal conductance. The stomatal index and the abscisic acid (ABA) content were unaffected in well-watered mutant leaves, but the ABA/stomatal conductance relation was altered during drought, indicating that specific factors interact with ABA signalling. Leaf hydraulic conductance was lower in mutant leaves when compared to WT leaves and the role of oxidative aquaporin gating in attaining a maximum stomatal conductance is discussed. In addition, differences in leaf metabolic status between the mutant and the WT might contribute to the low stomatal conductance, as reported for TCA cycle-deficient plants. After withholding watering, TCA cycle derived organic acids declined more in CMSII leaves than in the WT, and ATP content decreased only in the CMSII. Moreover, in contrast to the WT, total free amino acid levels declined whilst soluble protein content increased in CMSII leaves, suggesting an accelerated amino acid remobilisation. We propose that oxidative and metabolic disturbances resulting from remodelled respiration in the absence of Complex I activity could be involved in bringing about the lower stomatal and hydraulic conductances. 相似文献