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21.
This paper presents the work conducted on the
chemical constituents of some common and widely distributed
halophyte taxa from Cyprus with the aim that these studies will
help in the evaluation of halophytes for different economical
purposes. The plant species of Crithmum maritimum L., Limbarda
crithmoides (L.) Dumort, Atriplex portulacoides L., Salsola kali L.,
Atriplex halimus L., Limonium oleifolium Mill., L. meyeri (Boiss.)
Kuntze; and Tetraena alba (L.f.) Beier & Thulin were collected
in the middle of July. The shoot tissue and leaf samples were
collected from the natural habitats and left for drying under air
circulation followed by placing them in oven at 60 °C for 96
hours. The material was crushed using mortar and pestle and
subjected to an analysis of macro- and micro-nutrients and
biochemical compounds. K+/Na+ in the leaf tissues of the dicot
species showed relatively high values depicting their behavior
as Na+ includes but very low Cl- levels were recorded. Out of
the species investigated here in 4 TFAA content was rather high.
Values ranging from 0.5% to 1% dry weight were exhibited in one
species. However, only 3 species showed very low TFAA values.
Later may be due to low nitrogen availability in their environment.
The phenetic analyses of eight halophyte species performed on
the data matrix using Ntsys-pc program version 2.1 revealed
that, cluster analysis of the overall results obtained here leads to
2 clusters. This discrimination appears to be as a result of their
different abilities to accumulate either proline or glycine betaine. 相似文献
22.
Lipid peroxidation and antioxidant system in the blood of cancerous patients with metastasis 总被引:5,自引:0,他引:5
Free-radical-mediated damages may play an important role during metastasis. To investigate their relevance in the metastatic process MDA levels, glutathione peroxidase (GPX) and superoxide dismutase (SOD) activities, and selenium, zinc and copper contents were determined in plasma and erythrocytes from 20 cancerous patients with metastasis and 30 age-matched controls. Significantly higher concentrations of MDA in plasma as well as in erythrocytes were found comparing to the control group. In both plasma and erythrocytes, GPX activity and selenium and zinc levels were significantly lower in patients than in controls. However, SOD activity in erythrocytes and copper levels in both plasma and erythrocytes were significantly higher in patients. The impaired antioxidant system may favor accumulation of free radicals which may induce the process of metastasis. On the other hand, it is possible that the antioxidant system is impaired as a consequence of abnormality in the antioxidative metabolisms due to the cancer process. 相似文献
23.
Extracellular matrix formation (ECM) and remodeling are critical events related to the pathogenesis of pulmonary fibrosis. Matrix metalloproteinases play an essential role in degrading and remodeling the ECM. In this study, we tried to show the presence and correlation of promatrix metalloproteinase-3 (proMMP-3) (the inactive form of metalloproteinase-3) levels in coal workers' pneumoconiosis (CWP) with different categories. The study population consisted of 44 coal miners with CWP (pos CWP). Coal miners without CWP (neg CWP, n = 24) and non-underground personnel (controls, n = 17) were taken as controls. All coal miners were stable and had no systemic infection or disease. Standard posterio-anterior chest radiographs and pulmonary function tests were performed to exclude any diseases other than CWP. Serum proMMP-3 was analysed using the sandwich enzyme-linked immunosorbent assay according to the manufacturer's instructions (The Binding Site, Birmingham, UK). Mean proMMP-3 values of the all three groups were compared and a significant statistical difference obtained (p < 0.001). In addition, a statistically significant difference was found between categories of the disease and proMMP-3 values (p < 0.05). The effects of age, exposure duration and cigarette smoking on proMMP-3 values in coal miners with CWP were investigated. There were no correlations between age, smoking and proMMP-3 values. However, a positive correlation was found between exposure duration and proMMP-3 values (r = 0.447, p = 0.008). In conclusion, proMMP-3 (prostromelysin 1) may play an essential role in degrading and remodeling the ECM in workers with pneumoconiosis. ProMMP-3 may also reflect the stage of pneumoconiosis disease. 相似文献
24.
The preparation of 3,5-(E)-dieno-3,5,6,8-tetradeoxy-(S)-1,2-O-trichloroethylidene-alpha-D-glycero-octo-1,4-furano-7-ulose starting from either 1,2-O-(S)-trichloroethylidene-alpha-D-glucofuranose (beta-chloralose) or 1,2-O-(S)-trichloroethylidene-alpha-D-galactofuranose (galactochloralose) and the preparation of methyl 3,5-(E)-dieno-3,5,6-trideoxy-(S)-1,2-O-trichloroethylidene-alpha-D-glycero-hepta-1,4-furano-uronate starting from beta-chloralose are described. Endocyclic double bond formations were realised by the elimination of 3-acetoxy groups using DMF-sodium bicarbonate. This elimination was not successful when the starting compound was 1,2-O-(R)-trichloroethylidene-alpha-D-glucofuranose (alpha-chloralose), where the trichloromethyl group occupies the endo position. 相似文献
25.
Donor T cell activation initiates small bowel allograft rejection through an IFN-gamma-inducible protein-10-dependent mechanism 总被引:3,自引:0,他引:3
Zhang Z Kaptanoglu L Haddad W Ivancic D Alnadjim Z Hurst S Tishler D Luster AD Barrett TA Fryer J 《Journal of immunology (Baltimore, Md. : 1950)》2002,168(7):3205-3212
The poor success in controlling small bowel (SB) allograft rejection is partially attributed to the unique immune environment in the donor intestine. We hypothesized that Ag-induced activation of donor-derived T cells contributes to the initiation of SB allograft rejection. To address the role of donor T cell activation in SB transplantation, SB grafts from DO11.10 TCR transgenic mice (BALB/c, H-2L(d+)) were transplanted into BALB/c (isografts), or single class I MHC-mismatched (L(d)-deficient) BALB/c H-2(dm2) (dm2, H-2L(d-)) mutant mice (allografts). Graft survival was followed after injection of control or antigenic OVA(323-339) peptide. Eighty percent of SB allografts developed severe rejection in mice treated with antigenic peptide, whereas <20% of allografts were rejected in mice treated with control peptide (p < 0.05). Isografts survived >30 days regardless of OVA(323-339) administration. Activation of donor T cells increased intragraft expression of proinflammatory cytokine (IFN-gamma) and CXC chemokine IFN-gamma-inducible protein-10 mRNA and enhanced activation and accumulation of host NK and T cells in SB allografts. Treatment of mice with neutralizing anti-IFN-gamma-inducible protein-10 mAb increased SB allograft survival in Ag-treated mice (67%; p < 0.05) and reduced accumulation of host T cells and NK cells in the lamina propria but not mesenteric lymph nodes. These results suggest that activation of donor T cells after SB allotransplantation induces production of a Th1-like profile of cytokines and CXC chemokines that enhance infiltration of host T cells and NK cells in SB allografts. Blocking this pathway may be of therapeutic value in controlling SB allograft rejection. 相似文献
26.
27.
Keskintepe L Pacholczyk G Machnicka A Norris K Curuk MA Khan I Brackett BG 《Biology of reproduction》2002,67(2):409-415
Pronuclear formation, and the chromosomal constitution and developmental capacity of bovine zygotes formed by intracytoplasmic sperm injection with freeze-dried (lyophilized) spermatozoa were evaluated. Frozen-thawed spermatozoa were selected, freeze-dried, and stored at 4 degrees C until use. After 22-24 h of in vitro maturation oocytes were denuded and injected singly with a lyophilized spermatozoon. Injected oocytes were activated by treatment with 10 microM ionomycin (5 min) alone and in combination with 1.9 mM 6-dimethylaminopurine (DMAP) for 4 h. Ionomycin plus DMAP activation treatment resulted in a significantly higher proportion of sperm-injected oocytes with two pronuclei than was found after activation with ionomycin alone (74% vs. 56%; P < 0.03). The rates of cleavage, morula, and blastocyst development of sperm-injected oocytes treated with ionomycin plus DMAP were higher than after activation with ionomycin alone (63.3%, 34.2%, and 29.6% vs. 44.7%, 18.7%, and 10.6%, respectively; P < 0.05). Seventy-three percent of blastocysts produced with lyophilized sperm were diploid. These results demonstrate that in vitro-matured bovine oocytes can be fertilized with freeze-dried sperm cells, and that resultant zygotes can develop into karyotypically normal blastocysts. 相似文献
28.
29.
30.
This study was designed to measure the effect of iron supplementation on antioxidant status in iron-deficient anemia, including
the time for hemoglobin normalization and at the time of filling of iron body stores. The extent of plasma lipid peroxidation
was evaluated by measuring the levels of malondialdehyde and glutathione peroxidase (GSH-Px), and the activities of superoxide
dismutase (SOD) and catalase in 63 patients with iron-deficiency anemia before and after 6 wk of iron supplementation and
at the time when body iron stores are saturated. After 6 wk of iron supplementation, a significant decrease of oxidative stress
was observed in the treated subjects relative to controls (p<0.05). No significant differences existed between treated patients at 6 wk and at the end of the study. The erythrocyte levels
of catalase, SOD, and GSH-Px were significantly lower in treated patients relative to controls (p<0.05). These levels increased after 6 wk of supplementation (p<0.05) and showed no significant differences with those at the end of the study. 相似文献