Effect of Aging Heat Treatment on Wear Behavior and Microstructure Characterization of Newly Developed Al7075+Ti Alloys.

In this study, Al7075+0%Ti-, Al7075+2%Ti-, Al7075+4%Ti-, and Al7075+8%Ti-reinforced alloys were prepared by melting processes using Al7075 and Al-10%Ti main alloys. All newly produced alloys were subjected to T6 aging heat treatment and some samples were cold rolled at 5% beforehand. The microstructure, mechanical behavior, and dry-wear behavior of the new alloys were examined. Dry-wear tests of all alloys were carried out at a total sliding distance of 1000 m, at a sliding speed of 0.1 m/s, and under a load of 20 N. In the hardness measured after T6 aging heat treatment, the peak hardness of the Al7075+0%Ti-, Al7075+2%Ti-, Al7075+4%Ti-, and Al7075+8%Ti-reinforced alloys was found to be 105.63, 113.60, 122.44, and 140.41 HB, respectively. The secondary phases formed by the addition of Ti to the Al7075 alloy acted as precipitate-nucleation sites during aging heat treatment, further increasing the peak hardness. Compared to the peak hardness of the unrolled Al7075+0%Ti alloy, the increase in the peak hardness of the unrolled and rolled Al7075+8%Ti-reinforced alloys was 34% and 47%, respectively, and this difference in the increase was due to the change in the dislocation density with cold deformation. According to the dry-wear test results, the wear resistance of the Al7075 alloy increased by 108.5% with a reinforcement of 8% Ti. This result can be attributed to the formation of Al, Mg, and Ti-based oxide films during wear, as well as the precipitation hardening, the secondary hardening with acicular and spherical Al3Ti phases, the grain refinement, and solid-solution-hardening mechanisms.

Glycine alleviates liver injury induced by deficiency in methionine and or choline in rats.

OBJECTIVES: Nonalcoholic steatohepatitis (NASH) is an advanced stage of non-alcoholic fatty liver disease (NAFLD) from steatosis. Methionine and choline are important amino acids play a key role in many cellular functions. Glycine is a non-essential amino acid having multiple roles in many reactions. This study aimed to investigate liver damage induced by feeding male albino rats either methionine deficient (MD), choline deficient (CD), or MCD diets. And to clarify the alleviatory effect of dietary glycine supplementation (5%) on reduced complications caused by feeding each of the deficient diets. MATERIAL AND METHODS: Nutritional status, liver functions, lipids profile, hepatic oxidative stress, hepatic antioxidant enzymes, tumor markers and hepatic fatty acid transport protein gene were assessed. RESULTS: Rats fed with either MD or MCD diet had less body weight gain unlike rats fed the CD diet. Liver injury was detected in deficient groups by elevating plasma ALT, AST, ALP, total and direct bilirubin, albumin and protein levels. Lipid accumulation was more prominent in rats fed the MCD or CD diet than in those fed the MD diet. Fatty acid transport protein (FATP) was significantly elevated in the different glycine supplemented groups. CONCLUSION: Oral administration of glycine confers a significant protective effect by optimizing all the assessed parameters and gene expression.

New insights on the anti-inflammatory effect of some Egyptian plants against renal dysfunction induced by cyclosporine.

OBJECTIVE: This study was undertaken to investigate the anti-inflammatory role of fennel, carob, doum and mixture of them in improving the renal dysfunction induced in rats by the cyclosporine. DESIGN: Sixty female albino rats were divided into six groups: healthy control rats, cyclosporine injected rats (positive control), other groups were injected by cyclosporine for 7 days and then diet was supplemented with either fennel, doum, carob or mixture of them. After 45 days of supplementation, rats were scarified. Serum and urinary samples were obtained for different biochemical analysis. METHODS: The analysis included the determination of creatinine levels in serum and urinary samples, serum ammonia, transforming growth factor-beta1 (TGF-beta1) and tumor necrosis factor-alpha (TNF-alpha), urinary N-acetyl-beta D-glucosaminidase (NAG), beta2 microglobulin as well as calculating the creatinine clearance. Also, an histopathological examination for the kidney tissue was performed. RESULTS: The present study showed that cyclosporine induced the nephrotoxicity as appeared by elevation of serum and urinary levels of creatinine, urinary level of beta2 microglobulin, serum levels of ammonia, TGF-beta1 and TNF-alpha and the NAG level while decreased the creatinine clearance. Addition of fennel, carob, doum or mixture of them significantly improved the kidney functions. Moreover, anti-inflammatory status of animals injected with cyclosporine and supplemented with fennel, carob, doum and mixture of them, showed a significant amelioration in the kidney functions as compared to animals injected with the cyclosporine only. Histopathological investigation of kidney tissue of rat treated with the cyclosporine showed a moderate degree of renal damages. While, groups fed on fennel, carob, doum or mixture of them showed a great improvement in the kidney morphological structure. CONCLUSIONS: Diet supplementation with fennel, carob, doum have a promising anti-inflammatory influence on attenuating the complications associated with the renal dysfunction.