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981.
In microalgal culture collections, as in many biological resource centres, cryoconservation is the most attractive method for the long-term, secure storage of living material. Nannochloropsis oculata, a marine unicellular alga, is of interest in the field of biotechnology due to its high lipid content. Of various cryoprotectants tested for their toxicity and for their ability to prevent cryoinjury, glycerol (final concentration 1.1 M) was the most efficient. When glycerol-treated cultures were submitted to a strictly regulated cooling rate (-3 degrees C min(-1)), they attained the control culture density within 13 d after thawing. 相似文献
982.
The relationship between serum cytokine levels with obesity and obstructive sleep apnea syndrome 总被引:11,自引:0,他引:11
Inflammatory cytokines such as interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) may have a direct effect on glucose and lipid metabolism. On the other hand, it is known that IL-6 and TNF-alpha are important pro-inflammatory cytokines in the pathogenesis of atherosclerosis. The goal of present study was to test whether sleep apnea contributes to the previously reported increases of IL-6 and TNF-alpha independent of obesity. Forty-three obese (body mass index, BMI>27 kg/m2) men with newly diagnosed obstructive sleep apnea syndrome (OSAS) (apnea-hypopnea index, AHI> or =5) and age- and BMI-matched 22 obese nonapneic male controls (AHI<5) were enrolled in this study. To confirm the diagnosis, all patients underwent standard polysomnography in the sleep disorders center. Serum samples were taken at 08:00 h in the morning after overnight fasting. Serum IL-6 and TNF-alpha levels were found significantly higher in OSAS patients than in controls (p=0.002, p=0.03). Serum IL-6 and TNF-alpha levels were significantly correlated with AHI in OSAS patients (r=0.03, p=0.046 and r=0.36, p=0.016). There was no significant correlation between serum IL-6, TNF-alpha levels and AHI in controls. Serum IL-6 and TNF-alpha levels were not correlated with BMI both in OSAS patients and controls. In conclusion, circulating IL-6 and TNF-alpha levels in patients with OSAS, as independent of BMI are significantly higher than levels in controls and there is a positive relationship between previously mentioned cytokines' levels and the severity of OSAS. According to these results, the link between cardiovascular morbidity and OSAS may be explained by the coexistence of other cardiovascular risk factors such as circulating IL-6 and TNF-alpha levels. 相似文献
983.
A combination of a differentiation-inducing agent like 1alpha, 25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] with a compound that blocks entry of calcium into cells like vanadium (V) may offer a new approach to differentiation therapy and address the problem of hypercalcemia. Initiation of hepatocarcinogenesis was performed by a single intraperitoneal injection of diethylnitrosamine (DEN) (200 mg/kg b.wt.) in male Sprague-Dawley rats. Supplementation of V, 1, 25(OH)(2)D(3), or both V and 1,25(OH)(2)D(3) were started 4 weeks prior to DEN injection and continued thereafter till 20th week. It was observed that supplementation of V (0.5 ppm) in drinking water ad libitum or 1,25(OH)(2)D(3) (3 microg/ml propylene glycol) per os twice weekly for the entire period of the experiment significantly reduces the number and size of hyperplastic nodules while the combination treatment offered an additive effect in reducing it to 37.5% from 83.3%. V-1,25(OH)(2)D(3) combination was also effective in elevating the level of hepatic microsomal cytochrome P-450 (Cyt. P-450) (P<0.001). Moreover, A significant reduced level of cytosolic glutathione (GSH) (P<0.001) and glutathione S-transferase (GST) (P<0.001) activity as well as reduction in the appearance of gamma-glutamyltranspeptidase (GGT)-positive foci (P<0.001) as compared to carcinogen control were observed in V plus 1, 25(OH)(2)D(3) treated group. These results suggest that V may be useful in combination with 1,25(OH)(2)D(3) in the inhibition of experimental rat hepatocarcinogenesis. 相似文献
984.
985.
Cadmium-induced changes in epithelial cells of the rat stomach 总被引:1,自引:0,他引:1
Asar M Kayişli UA Izgüt-Uysal VN Oner G Kaya M Polat S 《Biological trace element research》2000,77(1):65-81
The aim of this study was to determine the changes in the function and fine structure of the gastric mucosa following exposure
to high cadmium (Cd) for 30 d in rats. In the present study, control antimals were fed with normal food and tap water and
the remaining animals received Cd (15 ppm CdCl2) in drinking water for the same period. Receiving Cd for 30 d increased the mean blood (p<0.01) and mucosa (p<0.001) Cd levels, while decreased mucus thickness, mucin content (p<0.01) significantly. Basal acid output fell significantly (p<0.01). Light and electron microscopic examination revealed the following: (1) Cd decreases the mean number of surface mucous,
isthmic-neck, parietal cells (p<0.05) and chief cells (p<0.001) per unit from the control value and (2) in some cells of zymogenic unit, the Cd-induced alterations were characterized
with dilated Golgi cisternae, focal enlarged endoplasmic reticulum, broken tubulovesicles, degenerated mitochondria, dense
nuclei, as well as lysosomal structures. We concluded that Cd augments the elimination rate of zymogenic unit’s cells by increasing
the alteration rate, and the reduced basal acid output, mucin content, and mucus thickness can be explained easily with the
loss of zymogenic unit’s cell population. 相似文献
986.
987.
988.
Demersal trawl discards with spatial and bathymetric emphasis in the Turkish coast of the Aegean Sea
The aim of the present study is to investigate the spatial and bathymetric distribution of demersal trawl discards in the Turkish coast of the Aegean Sea. Trawl hauls were performed in the legal trawling areas of the Turkish coast of the Aegean Sea (Çanakkale, Foça, Karaburun, S??ac?k, Güllük) between 2010 and 2012 by commercial trawlers. Depth of the trawl hauls ranged from 30?m in the south to 450?m in the north. As a result of 311 trawl samples, 200 species belonging to eight taxonomic groups (Porifera, Cnidaria, Annelida, Arthropoda, Mollusca, Echinodermata, Tunicata, Chordata) were identified. The changes in species composition based on depth and region were determined to be statistically significant. It was found that species composition distinctly changed around 200?m. In a regional assessment it was determined that the Turkish coast of the Aegean Sea is divided into three sub-regions, i.e. Çanakkale, Foça-Karaburun-S??ac?k and Güllük. The results of similar studies conducted in the Mediterranean were investigated and compared with the findings of this study. 相似文献
989.
Johnathan Cooper-Knock Tobias Moll Tennore Ramesh Lydia Castelli Alexander Beer Henry Robins Ian Fox Isabell Niedermoser Philip Van Damme Matthieu Moisse Wim Robberecht Orla Hardiman Monica P. Panades Abdelilah Assialioui Jesus S. Mora A. Nazli Basak Karen E. Morrison Christopher E. Shaw Pamela J. Shaw 《Cell reports》2019,26(9):2298-2306.e5