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71.
Wasif Nouman Shahzad Maqsood Ahmed Basra Azra Yasmeen Tehseen Gull Syed Bilal Hussain Muhammad Zubair Rehman Gul 《Plant Growth Regulation》2014,73(3):267-278
Moringa oleifera is a multipurpose plant which is now being promoted as a fodder crop. The present study was conducted to induce the tolerance in moringa plants to emerge and grow under saline conditions. For this, moringa seeds were primed with aerated water (hydropriming) and moringa leaf extract (MLE) for 12 and 24 h and studied for its emergence, potential growth behaviour, mineral composition, chlorophyll contents and antioxidant activities in comparison with unprimed seeds to investigate the physiological changes in moringa plants under saline conditions. The seeds were sown in plastic pots filled with acid washed sand at four salinity levels (3, 6, 10, 14 dS m?1) in a completely randomized design with three replications. It was found that salinity >6 dS m?1 reduced the emergence, growth and vigour of moringa plants but hydropriming (12 h) enhanced moringa emergence at 10 dS m?1 followed by MLE priming (12 h). Maximum aboveground biomass and photosynthetic pigments were recorded when the seeds were hydroprimed (12 h) but maximum root length and number of roots were found in MLE primed (12 h) moringa plants. Significant decrease in K+:Na+ ratio with increasing salinity levels resulted in low K+ and Mg2+ uptake and Na+ toxicity in moringa leaves which resulted in reduced chlorophyll contents at 14 dS m?1 but a significant increase in chlorophyll a and b contents and total phenolics were found in hydroprimed seeds (12 h) while the antioxidant activities of superoxide dismutase, peroxidase and catalas were improved by MLE priming (12 h). This study concludes that moringa emergence and growth performance can be improved by hydropriming under saline conditions. 相似文献
72.
Muhammad Saleem Sara Musaddiq Naheed Riaz Momina Zubair Muhammad Ashraf Rumana Nasar Abdul Jabbar 《Steroids》2013,78(11):1098-1102
Four new ecdysteroids (1–4), along with three known steroids, β-ecdysone (5), 5-β-2-deoxyintegristerone A (6) and 24-epi-makisterone A (7) (Fig. 1), were isolated from the methanolic extract of the flowers of Aerva javanica by using normal and reverse phase chromatography. The structures of the new compounds (1–4) were determined due to 1D (1H and 13C), 2D NMR (HSQC, HMBC, COSY, NOESY) techniques and high resolution mass spectrometry (HREIMS). The known compounds (5–7) were characterized based on the 1D NMR spectroscopy and mass spectrometry and by comparison with the literature values. All isolates were evaluated for their inhibitory activities against enzymes acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and lipoxygenase (LOX). 相似文献
73.
Muhammad Tausif Chaudhry Muhammad Zohaib Naseem Rauf Subhe Sadiq Tahir Shoukat Parvez 《Applied microbiology and biotechnology》2014,98(7):3133-3141
This study focuses on the possible use of Aspergillus fumigatus to remove acid violet 49 dye (AV49) from aqueous solution. In batch biosorption experiments, the highest biosorption efficiency was achieved at pH 3.0, with biosorbent dosage of 3.0 gL?1 within about 30 min at 40 °C. The Langmuir and Freundlich models were able to describe the biosorption equilibrium of AV49 onto fungal biomass with maximum dye uptake capacity 136.98 mg g?1. Biosorption followed a pseudo-second-order kinetic model with high correlation coefficients (R 2?>?0.99), and the biosorption rate constants increased with increasing temperature. Thermodynamic parameters indicated that the biosorption process was favorable, spontaneous, and endothermic in nature, with insignificant entropy changes. Fourier transform infrared spectroscopy strongly supported the presence of several functional groups responsible for dye–biosorbent interaction. Fungal biomass was regenerated with 0.1 M sodium hydroxide and could be reused a number of times without significant loss of biosorption activity. The effective decolorization of AV49 in simulated conditions indicated the potential use of biomass for the removal of color contaminants from wastewater. 相似文献
74.
Zubair Nizamudeen Robert Markus Rhys Lodge Christopher Parmenter Mark Platt Lisa Chakrabarti Virginie Sottile 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2018,1865(12):1891-1900
Extracellular vesicles (EVs) have prevalent roles in cancer biology and regenerative medicine. Conventional techniques for characterising EVs including electron microscopy (EM), nanoparticle tracking analysis (NTA) and tuneable resistive pulse sensing (TRPS), have been reported to produce high variability in particle count (EM) and poor sensitivity in detecting EVs below 50?nm in size (NTA and TRPS), making accurate and unbiased EV analysis technically challenging. This study introduces direct stochastic optical reconstruction microscopy (d-STORM) as an efficient and reliable characterisation approach for stem cell-derived EVs. Using a photo-switchable lipid dye, d-STORM imaging enabled rapid detection of EVs down to 20–30?nm in size with higher sensitivity and lower variability compared to EM, NTA and TRPS techniques. Imaging of EV uptake by live stem cells in culture further confirmed the potential of this approach for downstream cell biology applications and for the analysis of vesicle-based cell-cell communication. 相似文献
75.
Kristopher Kieft Alyssa Adams Rauf Salamzade Lindsay Kalan Karthik Anantharaman 《Nucleic acids research》2022,50(14):e83
Genome binning has been essential for characterization of bacteria, archaea, and even eukaryotes from metagenomes. Yet, few approaches exist for viruses. We developed vRhyme, a fast and precise software for construction of viral metagenome-assembled genomes (vMAGs). vRhyme utilizes single- or multi-sample coverage effect size comparisons between scaffolds and employs supervised machine learning to identify nucleotide feature similarities, which are compiled into iterations of weighted networks and refined bins. To refine bins, vRhyme utilizes unique features of viral genomes, namely a protein redundancy scoring mechanism based on the observation that viruses seldom encode redundant genes. Using simulated viromes, we displayed superior performance of vRhyme compared to available binning tools in constructing more complete and uncontaminated vMAGs. When applied to 10,601 viral scaffolds from human skin, vRhyme advanced our understanding of resident viruses, highlighted by identification of a Herelleviridae vMAG comprised of 22 scaffolds, and another vMAG encoding a nitrate reductase metabolic gene, representing near-complete genomes post-binning. vRhyme will enable a convention of binning uncultivated viral genomes and has the potential to transform metagenome-based viral ecology. 相似文献
76.
77.
Muhammad Umar Ijaz Ayesha Rauf Shama Mustafa Hussain Ahmed Asma Ashraf Khalid Al-Ghanim Satyanarayana Swamy Mruthinti S. Mahboob 《Saudi Journal of Biological Sciences》2022,29(3):1380-1385
Perfluorooctane sulfonate (PFOS) is an endocrine disruptor chemical (EDC) with potentially adverse effects on the male reproductive system. Pachypodol (5,4′-dihydroxy-3,7,3′-trimethoxyflavone) is a promising flavonoid isolated from Pogostemon cablin (Blanco) Benth that shows a broad range of pharmacological properties. However, the potential curative effects of pachypodol on testicular toxicity are not available until now. Therefore, this research was proposed to examine the efficiency of pachypodol against PFOS-induced testicular toxicity in adult male rats. The experiments were conducted on Sprague-Dawley rats (n = 48), which were equally distributed into four groups: control, PFOS (20 mg/kg), PFOS + Pachypodol (20 mg/kg + 10 mg/kg respectively), and Pachypodol (10 mg/kg). After 56 days of treatment, testes were excised by slaughtering rats, weighed, and stored till further analysis. The estimated parameters include biochemical markers, spermatogenic indices, hormonal and histopathological profiles. PFOS exposure disturbed the biochemical profile by altering the antioxidant/oxidant balance. For instance, it decreased the activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione reductase (GSR) while increasing the concentration of reactive oxygen species (ROS) and level of thiobarbituric acid reactive substances (TBARS). PFOS intoxication also led to a notable decline in viability, motility, epididymal sperm count, and the number of HOS coiled-tail sperms, whereas the higher level of abnormality in the head, mid-piece, and tail of sperms were observed. Besides, it lowered luteinizing hormone (LH), follicle-stimulating hormone (FSH), and plasma testosterone. In addition, PFOS exposure led to histopathological damages in testicles. However, pachypodol treatment potently alleviated all the illustrated impairments in testes. Conclusively, our results demonstrate the promising free-radical scavenging activity of pachypodol, a novel phytochemical, against the PFOS-instigated testicular dysfunctions. 相似文献
78.
G R Gunn A Zubair C Peters Z K Pan T C Wu Y Paterson 《Journal of immunology (Baltimore, Md. : 1950)》2001,167(11):6471-6479
Two recombinant Listeria monocytogenes (rLm) strains were produced that secrete the human papilloma virus-16 (HPV-16) E7 protein expressed in HPV-16-associated cervical cancer cells. One, Lm-E7, expresses and secretes E7 protein, whereas a second, Lm-LLO-E7, secretes E7 as a fusion protein joined to a nonhemolytic listeriolysin O (LLO). Lm-LLO-E7, but not Lm-E7, induces the regression of the E7-expressing tumor, TC-1, established in syngeneic C57BL/6 mice. Both recombinant E7-expressing rLm vaccines induce measurable anti-E7 CTL responses that stain positively for H-2D(b) E7 tetramers. Depletion of the CD8+ T cell subset before treatment abrogates the ability of Lm-LLO-E7 to impact on tumor growth. In addition, the rLm strains induce markedly different CD4+ T cell subsets. Depletion of the CD4+ T cell subset considerably reduces the ability of Lm-LLO-E7 to eliminate established TC-1 tumors. Surprisingly, the reverse is the case for Lm-E7, which becomes an effective anti-tumor immunotherapeutic in mice lacking this T cell subset. Ab-mediated depletion of TGF-beta and CD25+ cells improves the effectiveness of Lm-E7 treatment, suggesting that TGF-beta and CD25+ cells are in part responsible for this suppressive response. CD4+ T cells from mice immunized with Lm-E7 are capable of suppressing the ability of Lm-LLO-E7 to induce the regression of TC-1 when transferred to tumor-bearing mice. These studies demonstrate the complexity of L. monocytogenes-mediated tumor immunotherapy targeting the human tumor Ag, HPV-16 E7. 相似文献
79.
80.
The purpose of this study is to examine the antiarrhythmic and antioxidant effects of tamoxifen, one of the selective estrogen
modulators, in ovariectomized rats subjected to myocardial ischemia-reperfusion (I/R) injury. A month after ovariectomy, rats
were divided into four groups: (I) ovariectomized controls without any treatment, (II) ovariectomized rats treated with vehicle
dimethylsulfoxide (DMSO), (III)–(IV) ovariectomized rats treated with tamoxifen 1 or 10 mg/kg,sc daily for 14 days. To produce
arrhythmia, the left main coronary artery was occluded for 7 min, followed by 7 min of reperfusion. The blood pressure (BP),
heart rate (HR), electrocardiography (ECG) was recorded before and during the ischemia-reperfusion period. The blood levels
of malondialdehyde (MDA), creatine kinase (CK), glutathione (GSH), glutathione peroxidase (GSH-Px), glutathione reductase
(GR), and catalase (CAT) were measured after the rats were killed. Tamoxifen reduced the incidence of ventricular tachycardia
(VT) on ischemia and reperfusion as well as the incidence and duration of reversible ventricular fibrillation (VF) on reperfusion.
I/R injury caused a significant fall in GSH, GSH-Px as well as an increase in MDA and CK levels in the control group when
compared to tamoxifen treated groups. The changes in levels of CAT and GR were however, not significant. In conclusion, our
findings suggest that tamoxifen has cardioprotective effects against I/R injury in rats, likely its antioxidant properties. 相似文献