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91.
Background. N‐acetyl cystein, a mucolytic agent, might make Helicobacter pylori antigens shed more easily to stool, and might therefore contribute to the diagnostic accuracy of the Helicobacter pylori stool antigen test. The aim of this study is to investigate if N‐acetyl cystein contributes to the diagnostic accuracy of the Helicobacter pylori stool antigen test by increasing the sensitivity and specificity of the test. Materials and Methods. 107 patients were separated into treatment and placebo groups. The AC group (n = 53) was given 5 ml of acetyl cystein (4%) t.i.d. and the Placebo group (n = 54) was given placebo, for 3 days. Helicobacter pylori status was determined by both histology and CLOtest. Stool samples were assayed using a specific ELISA kit for Helicobacter pylori stool antigen. Results. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of Helicobacter pylori stool antigen test were 76%, 79%, 90%, 55%, and 77%, respectively, in AC group; and 85%, 89%, 93%, 76% and 86%, respectively, in placebo group. Conclusions. N‐acetyl cystein did not increase, and actually decreased, the sensitivity and specificity of the Helicobacter pylori stool antigen test according to our results. We believe that this finding can be taken into consideration when setting up the exclusion criteria for future studies, which will use Helicobacter pylori stool antigen tests. 相似文献
92.
Solvent-free glycerolysis of sunflower oil catalyzed with lipase D Amano 100 gave the highest partial acylglycerols content at 40°C using an oil:glycerol molar ratio of 1:2 and 500 Units lipase/ g oil. After 6 h, the partial acylglycerols content of the reaction mixture was 53% (w/w). Glycerolysis of anchovy oil catalyzed under the same conditions gave a partial acylglycerols content of 47% (w/w) after 24 h. 相似文献
93.
Zhuqing Qu Levent Balkir Judith C.T. van Deutekom Paul D. Robbins Ryan Pruchnic Johnny Huard 《The Journal of cell biology》1998,142(5):1257-1267
Myoblast transplantation has been extensively studied as a gene complementation approach for genetic diseases such as Duchenne Muscular Dystrophy. This approach has been found capable of delivering dystrophin, the product missing in Duchenne Muscular Dystrophy muscle, and leading to an increase of strength in the dystrophic muscle. This approach, however, has been hindered by numerous limitations, including immunological problems, and low spread and poor survival of the injected myoblasts. We have investigated whether antiinflammatory treatment and use of different populations of skeletal muscle–derived cells may circumvent the poor survival of the injected myoblasts after implantation. We have observed that different populations of muscle-derived cells can be isolated from skeletal muscle based on their desmin immunoreactivity and differentiation capacity. Moreover, these cells acted differently when injected into muscle: 95% of the injected cells in some populations died within 48 h, while others richer in desmin-positive cells survived entirely. Since pure myoblasts obtained from isolated myofibers and myoblast cell lines also displayed a poor survival rate of the injected cells, we have concluded that the differential survival of the populations of muscle-derived cells is not only attributable to their content in desmin-positive cells. We have observed that the origin of the myogenic cells may influence their survival in the injected muscle. Finally, we have observed that myoblasts genetically engineered to express an inhibitor of the inflammatory cytokine, IL-1, can improve the survival rate of the injected myoblasts. Our results suggest that selection of specific muscle-derived cell populations or the control of inflammation can be used as an approach to improve cell survival after both myoblast transplantation and the myoblast-mediated ex vivo gene transfer approach. 相似文献
94.
Arteriovenous malformations (AVMs), masses of abnormal blood vessels which grow in the brain, produce high flow shunts that steal blood from surrounding brain tissue, which is chronically hypoperfused. Hypoperfusion is a condition of inadequate tissue perfusion and oxygenation, resulting in abnormal tissue metabolism. Fourier transform infrared (FTIR) spectroscopy is used in this study to investigate the effect of hypoperfusion on homogenized rat brain samples at the molecular level. The results suggest that the lipid content increases, the protein content decreases, the lipid-to-protein ratio increases, and the state of order of the lipids increases in the hypoperfused brain samples. FTIR results also revealed that, owing to hypoperfusion, not only the protein synthesis but also the protein secondary structure profile is altered in favor of -sheets and random coils. These findings clearly demonstrate that, FTIR spectroscopy can be used to extract valuable information at the molecular level so as to have a better understanding of the effect of hypoperfusion on rat brain. 相似文献
95.
96.
Cavas L 《Cell biochemistry and function》2005,23(1):59-63
Antioxidant enzymes in erythrocytes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and antioxidant sex hormone oestradiol in serum and malondialdehyde (MDA) production as a marker of lipid peroxidation in erythrocytes were investigated in male and female underwater rugby (UWR) players. Results showed that except for GSH-Px activity in female players, all antioxidant enzymes increased significantly (p < 0.05) after an UWR game. It was interesting to note that while the concentration of oestradiol in female players did not change, it increased significantly (p < 0.05) in male players. Lipid peroxidation (LPO) levels in female players as well as oestradiol concentration did not change significantly (p > 0.05) whereas LPO levels in male players increased significantly (p < 0.05) compared to pre-exercise values. In conclusion, the results showed that underwater rugby can stimulate over-production of ROS and antioxidant systems and affect oestradiol levels in male players. Because of increased LPO levels observed in male players, complex antioxidant supplementation including co-factors of antioxidant enzymes such as Cu, Zn, Fe, Se and antioxidant vitamins such as vitamin C and E may be recommended to players before the UWR game. 相似文献
97.
Buldum Gizem Bismarck Alexander Mantalaris Athanasios 《Bioprocess and biosystems engineering》2018,41(2):265-279
Bioprocess and Biosystems Engineering - Bacterial cellulose (BC) exhibits unique properties such as high purity compared to plant-based cellulose; however, commercial production of BC has remained... 相似文献
98.
Reactive oxygen species (ROS) are of great importance in plant metabolism. However, uncontrolled activation of ROS might have deleterious effects in cells. Eleven Mediterranean countries are still under threat of an introduced taxon of Caulerpa racemosa var. cylindracea. In the present study, it has been aimed to compare the antioxidant status of this highly invasive alga with some Mediterranean macrophytes collected in the same habitat. For this purpose, such antioxidant enzyme activities as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and lipid peroxidation (LPO) as well, levels have been determined in C. racemosa, Cystoseira barbata C. Agardh, Padina pavonica (Linnaeus) Thivy and Enteromorpha sp. The highest SOD, CAT, GSH-Px enzyme activities and the lowest LPO level have been measured in the invasive C. racemosa. In conclusion, C. racemosa var. cylindracea seems more tolerant in warring with ROS than the Mediterranean species tested do. These results could partly explain the amazing success of C. racemosa var. cylindracea introduced in the Mediterranean. 相似文献
99.
100.
Dagdelen Duriye Nur Akkulak Aysenur Donmez Yalcin Gizem 《Molecular biology reports》2021,48(4):3495-3502
Molecular Biology Reports - Glioblastoma multiform is a primary brain tumor derived from glial cells. The aim of this study is to investigate how glutamate metabolism is regulated by glutamate... 相似文献