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41.

Background

During tumor angiogenesis, endothelial cells (ECs) are engaged in a number of energy consuming biological processes, such as proliferation, migration, and capillary formation. Since glucose uptake and metabolism are increased to meet this energy need, the effects of the glycolytic inhibitor 2-deoxy-D-glucose (2-DG) on in vitro and in vivo angiogenesis were investigated.

Methodology/Principal Findings

In cell culture, 2-DG inhibited EC growth, induced cytotoxicity, blocked migration, and inhibited actively forming but not established endothelial capillaries. Surprisingly, 2-DG was a better inhibitor of these EC properties than two more efficacious glycolytic inhibitors, 2-fluorodeoxy-D-glucose and oxamate. As an alternative to a glycolytic inhibitory mechanism, we considered 2-DG''s ability to interfere with endothelial N-linked glycosylation. 2-DG''s effects were reversed by mannose, an N-linked glycosylation precursor, and at relevant concentrations 2-DG also inhibited synthesis of the lipid linked oligosaccharide (LLO) N-glycosylation donor in a mannose-reversible manner. Inhibition of LLO synthesis activated the unfolded protein response (UPR), which resulted in induction of GADD153/CHOP and EC apoptosis (TUNEL assay). Thus, 2-DG''s effects on ECs appeared primarily due to inhibition of LLOs synthesis, not glycolysis. 2-DG was then evaluated in two mouse models, inhibiting angiogenesis in both the matrigel plug assay and the LHBETATAG transgenic retinoblastoma model.

Conclusions/Significance

In conclusion, 2-DG inhibits endothelial cell angiogenesis in vitro and in vivo, at concentrations below those affecting tumor cells directly, most likely by interfering with N-linked glycosylation rather than glycolysis. Our data underscore the importance of glucose metabolism on neovascularization, and demonstrate a novel approach for anti-angiogenic strategies.  相似文献   
42.
Bedir E  Manyam R  Khan IA 《Phytochemistry》2003,63(8):977-983
A neo-clerodane type diterpenoid, 12(S)-15,16-epoxy-19-hydroxy-neo-cleroda-13(16),14-dien-18,6alpha:20,12-diolide, and two phenylethanoid glycosides, teucrioside-3(IIII)-O-methylether and teucrioside-3(IIII),4(IIII)-O-dimethylether were isolated from the aerial parts of Teucrium chamaedrys. Their structures were identified on the basis of extensive NMR spectra, LC-ESIMS analysis, and molecular modeling studies.  相似文献   
43.
The aim of the study was to investigate how zinc deficiency and supplementation effect some hematologic parameters of rats performing swimming exercise. Forty adult male Spraque-Dawley rats were divided into 4 groups, zinc deficient swimming group (Group 1, n=10, zinc supplemented swimming group (Group 2, n=10), swimming control group (Group 3, n=10), and control group (Group 4, n=10). Blood samples were taken by decapitation and analyzed for the determination of erythrocyte, hemoglobin level, hematocrit, leukocyte, lymphocyte, platelet count and plasma zinc level at the end of the 4 week experiment. Erythrocyte count of group 1 was the lowest whereas erythrocyte count in group 3 was significantly lower than that in group 2 and 4 (p<0.05). Hemoglobin level of group 1 was significantly lower than that of groups 2 and 4 (p<0.05). Hematocrit was significantly lower in both group 1 and group 3 than both groups 2 and 4 (p<0.05). Lymphocyte count in group 2 was significantly higher than in all other groups (p<0.05). Platelet counts in group 2 was significantly lower than in all other groups (p<0.05). Our findings suggest that zinc deficiency effects the hematologic parameters mentioned negatively whereas zinc supplementation has a positive influence.  相似文献   
44.
In this study, the kinetics of disappearance of radioactivity in aerobic composting was investigated. For this purpose, compost materials were prepared by mixing sugar beet wastes, wine factory wastes (grape wastes), straw and biological treatment sludge in different amounts. While alpha-radioactivity was not initially detected in all composting materials, the composting materials had some beta-radioactivity. In the mixtures of sugar beet wastes--straw-biological treatment sludge (1), sugar beet wastes-wine factory wastes (grape wastes)-biological treatment sludge (II) and wine factory wastes (grape wastes)-biological treatment sludge (III), the beta-radioactivity reduced by 82%, 58%, 85% respectively of initial values after 52 d. The beta-radioactivity degradation in the composting process could be represented by first-order kinetics and reaction rate constants of mixtures of I, II and III were k = 0.0693 d(-1) (R2 - 0.84), k = 0.0453 d(-1) (R2 = 0.98), k = 0.0234 d(-1) (R2 = 0.97), respectively.  相似文献   
45.
Serum insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3) levels were investigated in 31 children living in an endemic goiter area and 33 healthy subjects living in an nonendemic area. Serum IGF-I and IGFBP-3 levels of iodine- and selenium-deficient children were found to be lower than those of control subjects (p<0.001). There was a positive correlation between the IGF-I with chronological age and body mass index. There was also positive correlation between the IGF-I and IGFBP-3. No significant difference was found between the goitrous and nongoitrous children. These results suggest that IGF-I and IGFBP-3 levels are affected by thyroid dysfunction as a result of iodine and selenium deficiency. However, IGF-I and IGFBP-3 levels are not associated with goiter.  相似文献   
46.
The inhalation of a wide range of organic solvents has become popular among young adults. Toluene is one of the most commonly used solvents in industry; it is easily available and conventient to use. Many toxicologic effects on biological systems secondary to deliberate inhalation of toluene have been reported, but investigations on adverse effects associated with bone morbidity is limited. The purpose of this study is to determine bone mineralization and investigate the adverse effects of toluene on bone. The bone mineral density and content of the femoral neck of mice exposed to toluene at 300 ppm for 8 wk were measured by dual X-ray absorptiometry and found significantly reduced compared to the control group. Chronic exposure to toluene was found to affect bone metabolism, and toluene-induced changes could contribute to bone resorption and inhibition of bone formation. Toluene seems to be the responsible component for the demineralizating effects of commonly abused substances, and medical doctors must promote their education about the health hazards in those who abuse solvents especially in areas where inhalant abuse is endemic.  相似文献   
47.
Behavioral responses of larvae and adults of cotton bollworm, Helicoverpa armigera to cotton with (GK-12) and without (SI-3) expression of the CrylAc -endotoxin protein of Bacillus thuringiensis (Bt) Berliner were observed during 2001 and 2002. Our results showed that 8.3% individuals fed with flowers and bolls of GK-12 could develop from neonate to pupa; however, pupal weight decreased by 48.6% and duration of development was delayed by 7.6 days compared with those fed with flowers–bolls of SI-3. Deterrence index (DI) of larvae decreased in later instars, which indicated that the Bt toxin decreased with age. Feeding frequency of 4th-instar larvae on GK-12 leaves decreased by 38.8%, but movement frequency increased by 37.1%. Larvae moved at least one plant away by the age of 10 days in both pure and mixed plantings of SI-3 and GK-12 in the field. Adults preferred to lay eggs on SI-3. The total number of eggs deposited on SI-3 plants in 3 days were about 232 and 95% greater than that on GK-12 plants at bud–flower stage and flower–boll stage, respectively. Based on the behavior of larva and adults in response to the transgenic cotton, the potential effect of refuge strategy in resistance management of H. armigera is discussed.  相似文献   
48.
The most common chromosomal anomaly is 45,X in the Turner syndrome. In addition to this, anomaly, mosaicism such as structural 46,X,i(Xq), 46,X,del(Xp), 46,X,r(X), 46,X,t(X;Y) and numerical 46XO/46,XX/47XXX are seen rather frequently. An infant with the Turner syndrome was found to have a karyotype 45X,t(1;2) (q41;p16) using high resolution banding. Based on our knowledge, we present the first case of 45X,t(1;2) (q41;p11.2), a karyotype in Turner's syndrome in the literature.  相似文献   
49.
50.
We compared spectrophotometric analysis of the umbilical cords of infants with meconium aspiration syndrome (MAS) or with meconium-stained amniotic fluid (MSAF) and healthy infants. In a prospective study, 15 infants with MAS and 37 infants with MSAF were enrolled. Twenty healthy infants formed a control group. The absorption peak of umbilical cords with meconium was significantly higher in the infants with MAS or MSAF than in controls. Spectrophotometric analysis of the umbilical cords with meconium may be useful to identify developed neonates with MAS or MSAF.  相似文献   
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