scholarly journals Pre‐treatment of ram semen extender with magnetic nanoparticles on freeze‐thawed spermatozoa

Author(s):  
Maryam Moradi ◽  
Hadi Hajarian ◽  
Hamed Karamishabankareh ◽  
Leila Soltani ◽  
Bijan Soleymani
Author(s):  
Sanu Mathew Simon ◽  
M. S. Sajna ◽  
V. P. Prakashan ◽  
Twinkle Anna Jose ◽  
P. R. Biju ◽  
...  

2016 ◽  
Vol 13 (1) ◽  
pp. 43 ◽  
Author(s):  
Yipei Sheng ◽  
Huaqin Guan ◽  
Yanfang Zhang ◽  
Xuemei Zhang ◽  
Qingqing Zhou ◽  
...  

Environmental context Conventional pre-treatment methods are usually ineffective for the extraction of bisphenol A (BPA) from environmental water samples. We report that a novel magnetic nanoparticle with double-functionalisation is an excellent solid-phase adsorbent for extracting BPA from river water samples. This study provides a simple but efficient approach for extraction of low-concentration pollutants from water samples. Abstract In this study, double functionalised magnetic nanoparticles (DFMNPs) for extraction of bisphenol A (BPA) in an aqueous phase were designed and prepared. In the preparation of DFMNPs, amide and pyridine groups were simultaneously introduced into the surface of magnetic nanoparticles. A new dispersed solid-phase extraction (DSPE) method adopting DFMNPs as the adsorbents was developed for separating and enriching BPA from river water samples. This DSPE method showed fast magnetic response, high binding efficiency to target BPA, and short experimental time. The recovery of BPA in spiked river water was 94.4% with the DSPE method, which was much higher than those with traditional solid-phase extraction (SPE) methods. The high performance of DFMNPs on extraction of BPA from river water was attributed to the synergistic function of the amide and pyridine groups. The hydrophilic amide groups caused DFMNPs to disperse well in water, whereas the alkaline pyridine groups bound BPA effectively by ionic bonds. Our DSPE was particularly superior to conventional SPE in the pre-treatment of large-volume water samples as the time taken could be remarkably reduced.


Author(s):  
E Y. Wang ◽  
J. T. Cherian ◽  
A. Madsen ◽  
R. M. Fisher

Many steel parts are electro-plated with chromium to protect them against corrosion and to improve their wear-resistance. Good adhesion of the chrome plate to the steel surface, which is essential for long term durability of the part, is extremely dependent on surface preparation prior to plating. Recently, McDonnell Douglas developed a new pre-treatment method for chrome plating in which the steel is anodically etched in a sulfuric acid and hydrofluoric acid solution. On carbon steel surfaces, this anodic pre-treatment produces a dark, loosely adhering material that is commonly called the “smut” layer. On stainless steels and nickel alloys, the surface is only darkened by the anodic pre-treatment and little residue is produced. Anodic pre-treatment prior to hard chrome plating results in much better adherence to both carbon and alloy steels.We have characterized the anodic pre-treated steel surface and the resulting “smut” layer using various techniques including electron spectroscopy for chemical analysis (ESCA) on bulk samples and transmission electron microscopy (TEM) and electron energy-loss spectroscopy (EELS) on stripped films.


2021 ◽  
Vol 160 (1) ◽  
pp. 234-243
Author(s):  
Diana Samoil ◽  
Nazek Abdelmutti ◽  
Lisa Ould Gallagher ◽  
Nazlin Jivraj ◽  
Naa Kwarley Quartey ◽  
...  

2004 ◽  
Vol 74 (1) ◽  
pp. 74-85 ◽  
Author(s):  
Liu ◽  
Russell ◽  
Smith ◽  
Bronson ◽  
Milbury ◽  
...  

Because reactive oxygen species have been implicated as mediators of inflammatory bowel disease (IBD), we evaluated the potential preventive and therapeutic effects of two dietary antioxidants, glutathione (GSH) and coenzyme Q10 (CoQ10) on dextran sulfate sodium (DSS)-induced colitis in mice. Fifty female 8-wk old Swiss-Webster mice were randomly assigned to 4 groups for a pre-treatment 'prevention' study: (1) GSH (1% of diet); (2) CoQ10 (200 mg/kg/d); (3) DSS only (3% of drinking water); (4) control (no treatment). The mice in groups 1 and 2 were fed with GSH or CoQ10 for 21 wks, and the mice in groups 1, 2 and 3 were provided DSS from wk 7 for 4 cycles (1 cycle = 1 wk DSS followed by 2-wk water). Another 50 mice were randomly assigned to 4 groups for a 21-wk 'treatment' study where the mice in groups 1, 2, and 3 were administered DSS for 6 cycles (18 wks) to induce colitis. GSH and CoQ10 were added from wk 7 until the completion of the protocol. Loose stools and hemocult positivity were modestly but significantly reduced with GSH or CoQ10 at several periods during the intervention in both the prevention and treatment studies. In contrast, histological evaluation revealed increases in colonic dysplasia and ulceration with GSH or CoQ10. Thus, in this mouse model, GSH and CoQ10 appear to have a beneficial effect on acute signs of IBD, but may have an adverse impact on the chronic pathophysiology of the disease. Further studies using additional animal models are required to determine whether GSH or CoQ10 provide a favorable or unfavorable benefit:risk ratio in the prevention or treatment of IBD.


2014 ◽  
Vol 84 (3-4) ◽  
pp. 0140-0151 ◽  
Author(s):  
Thilaga Rati Selvaraju ◽  
Huzwah Khaza’ai ◽  
Sharmili Vidyadaran ◽  
Mohd Sokhini Abd Mutalib ◽  
Vasudevan Ramachandran ◽  
...  

Glutamate is the major mediator of excitatory signals in the mammalian central nervous system. Extreme amounts of glutamate in the extracellular spaces can lead to numerous neurodegenerative diseases. We aimed to clarify the potential of the following vitamin E isomers, tocotrienol-rich fraction (TRF) and α-tocopherol (α-TCP), as potent neuroprotective agents against glutamate-induced injury in neuronal SK-N-SH cells. Cells were treated before and after glutamate injury (pre- and post-treatment, respectively) with 100 - 300 ng/ml TRF/α-TCP. Exposure to 120 mM glutamate significantly reduced cell viability to 76 % and 79 % in the pre- and post-treatment studies, respectively; however, pre- and post-treatment with TRF/α-TCP attenuated the cytotoxic effect of glutamate. Compared to the positive control (glutamate-injured cells not treated with TRF/α-TCP), pre-treatment with 100, 200, and 300 ng/ml TRF significantly improved cell viability following glutamate injury to 95.2 %, 95.0 %, and 95.6 %, respectively (p < 0.05).The isomers not only conferred neuroprotection by enhancing mitochondrial activity and depleting free radical production, but also increased cell viability and recovery upon glutamate insult. Our results suggest that vitamin E has potent antioxidant potential for protecting against glutamate injury and recovering glutamate-injured neuronal cells. Our findings also indicate that both TRF and α-TCP could play key roles as anti-apoptotic agents with neuroprotective properties.


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