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61.
Angiogenesis is required in cancer, including gynecological cancers, for the growth of primary tumors and secondary metastases. Development of anti-angiogenesis therapy in gynecological cancers and improvement of its efficacy have been a major focus of fundamental and clinical research. However, survival benefits of current anti-angiogenic agents, such as bevacizumab, in patients with gynecological cancer, are modest. Therefore, a better understanding of angiogenesis and the tumor microenvironment in gynecological cancers is urgently needed to develop more effective anti-angiogenic therapies, either or not in combination with other therapeutic approaches. We describe the molecular aspects of (tumor) blood vessel formation and the tumor microenvironment and provide an extensive clinical overview of current anti-angiogenic therapies for gynecological cancers. We discuss the different phenotypes of angiogenic endothelial cells as potential therapeutic targets, strategies aimed at intervention in their metabolism, and approaches targeting their (inflammatory) tumor microenvironment.  相似文献   
62.
We investigated both the effect of levosimendan and the role of oxidant/antioxidant status and trace element levels in the pulmonary artery of rats. Fourteen male Wistar albino rats were randomly divided into two groups of seven animals each. Group 1 was not exposed to levosimendan and served as a control. Levosimendan (12 μg/kg) diluted in 10 ml 0.9 % NaCl was administered intraperitoneally to group 2. Animals of both groups were killed after 3 days, and their pulmonary arteries were harvested to determine changes in tissue oxidant/antioxidant status and trace element levels. The animals in both groups were killed 72 h after the levosimendan exposure treatment, and pulmonary arteries were harvested to determine levels of the lipid peroxidation product MDA and the antioxidant GSH as well as the decreased activity of antioxidant enzymes such as SOD, GSH-Px and CAT. It was found that MDA levels increased in pulmonary artery tissues of rats after levosimendan administration. The GSH level decreased in the pulmonary artery of rats after levosimendan treatment. Co, Mn, Fe, Cd and Pb levels were significantly higher (P < 0.001) and Mg, Zn and Cu levels significantly lower (P < 0.001) in the levosimendan group compared to the control group. These results suggest that levosimendan treatment caused an increase in free radical production and a decrease in antioxidant enzyme activity in the pulmonary artery of levosimendan-treated rats. It also caused a decrease or increase in the levels of many minerals in the pulmonary artery, which is an undesirable condition for normal pharmacological function.  相似文献   
63.
In this study, the pollen morphology of 11 taxa belonging to Atossa (Alef.) Asch. & Graebner, Hypechusa (Alef.) Asch. & Graebner, Peregrinae Kupicha, Wiggersia (Alef.) Maxted, Vicia L. and Narbonensis (Radzhi) Maxted sections of the genus Vicia L. subgenus Vicia (Fabeae, Fabaceae) naturally growing in Turkey has been studied using Light Microscopy (LM) and Scanning Electron Microscopy (SEM) to evaluate the taxonomic relevance of pollen characters. Twelve morphometric characters are analysed with one-way analysis of variance and Tukey’s honestly significant difference test for multiple comparisons. Of the taxa studied V. narbonensis var. narbonensis (sect. Narbonensis) has the largest pollen grains (P = 51.98 μm × E = 30.52 μm) and V. lathyroides (sect. Wiggersia) has the smallest pollen grains (P = 27.71 μm × E = 20.14 μm). The pollen grains are subprolate to perprolate (P/E = 1.16–2.11), but the prolate shape occurs in the majority of the taxa. The regular pollen grains of all taxa are trizonocolporate, isopolar, and released in monads. Ornamentation of the mesocolpium is psilate-perforate in V. lathyroides (sect. Wiggersia), reticulate-rugulate in V. narbonensis var. narbonensis (sect. Narbonensis), (micro)reticulate in V. sericocarpa var. sericocarpa (sect. Hypechusa), V. sativa subsp. sativa (sect. Vicia) and V. grandiflora var. grandiflora (sect. Vicia), and reticulate-perforate in the remaining taxa. The apocolpium and colpus area are psilate or perforate in all taxa except V. sericocarpa var. sericocarpa (sect. Hypechusa) and V. sativa subsp. sativa (sect. Vicia), which exhibit the obscurely reticulate-perforate pattern. Several palynological features have taxonomic importance in sectional level: polar axis, equatorial diameter, pollen shape (P/E ratio), colpus length, colpus width, size of pori, porus length/width ratio, lumina diameter, muri thickness and ornamentation. The results also indicate that pollen characters can be useful in distinguishing the examined taxa.  相似文献   
64.
65.
Verbascum L. (Scrophulariaceae) species are used for desiccating wounds and as a fish poison in Anatolia as well as for diarrhea and dysentery of animals in several countries. To further evaluate their activity, methanolic extracts obtained from 13 Verbascum species growing in Turkey, including V. chionophyllum Hub.-Mor., V. cilicicum Boiss., V. dudleyanum (Hub.-Mor.) Hub.-Mor., V. lasianthum Boiss., V. latisepalum Hub.-Mor., V. mucronatum Lam., V. olympicum Boiss., V. pterocalycinum var. mutense Hub.-Mor., V. pycnostachyum Boiss. & Heldr., V. salviifolium Boiss., V. splendidum Boiss., V. stachydifolium Boiss. & Heldr. and V. uschackense (Murb.) Hub.-Mor. were evaluated for their in vivo anthelmintic activity. The extracts from V. lasianthum, V. latisepalum, V. mucronatum and V. salviifolum showed the highest inhibitory rates against Aspiculuris tetraptera at 100 mg/kg in mice. Additionally, extracts from V. dudleyanum and V. pterocalycinum var. mutense were found generally highly effective. The remaining species did not show any activity. Results of the present study support the utilization of these plant species employed in Turkish folk medicine.  相似文献   
66.
In this study, we aimed to investigate a possible association of the COX-2 polymorphisms (−765G→C and −1195A→G) and with the risk of developing epithelial ovarian carcinoma (EOC). COX-2 gene polymorphisms was investigated in 111 healthy women and 57 patients with EOC. Individuals who had −765 CG, −1195 AA genotype, and −765 C allele had increased risk for ovarian carcinoma (P < 0.01) and individuals with −765 GG, −1195 AG genotypes and −1195 G allele seem to be protected from ovarian carcinoma (P < 0.01). Haplotype analysis confirmed the association of COX-2 gene variants with ovarian carcinoma and revealed that the frequencies of −765C: −1195A haplotype frequencies was significantly higher in patients as compared with those of controls (P = 0.048). We state that there appears to be a modulating role for the COX-2 −1195A→G and −765G→C polymorphisms in the development of EOC. To the best of our knowledge, this is the first study to show such an association.  相似文献   
67.
Kahraman H  Aytan E  Kurt AG 《BMB reports》2011,44(9):590-594
The production of antileukemic enzyme methionine γ-lyase (MGL) in distinctly related bacteria, Citrobacter freundii and in their recombinants expressing the Vitresocilla hemoglobin (VHb) has been studied. This study concerns the potential of Citrobacter freundii expressing the Vitreoscilla hemoglobin gene (vgb) for the methionine γ- liyase production. Methionine γ- liyase production by Citrobacter freundii and its vgb(-) and vgb(+) bearing recombinant strain was studied in shake-flasks under 200 rpm agitation, culture medium and 30 °C in a time-course manner. The vgb(+) and especially the carbon type had a dramatic effect on methionine γ- liyase production. The vgb(+) strain of C. freundii had about 2-fold and 3.1-fold higher levels of MGL than the host and vgb(-) strain, respectively.  相似文献   
68.
In this study, our aim was to investigate the association of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism on the vitamin B12 therapy response in 95 patients with vitamin B12 deficiency and 92 healthy control subjects using vitamin B12, plasma total homocysteine (tHcy), and folate as the main measure of outcome. MTHFR C677T genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism techniques. There were no differences in the distribution of MTHFR genotypes in the cases versus the controls. Mean concentrations of plasma tHcy and B12 vitamin were 18.84 μM and 142.47 pg/mL in patients with TT (10.5%) genotypes. Furthermore, mean concentrations of B12 vitamin after cobalamin therapy were 697.62, 656.64, and 488.76 pg/mL in patients with the CC, CT, and TT genotypes, respectively. The MTHFR 677 TT genotype has decreasing effect in B12 vitamin and increasing effect in tHcy. In comparison with the patients having CC and CT genotypes, patients with the TT genotype had a lower response to vitamin B12 therapy.  相似文献   
69.
This study concerns the potential use of Pseudomonas aeruginosa expressing the Vitreoscilla hemoglobin gene for the degradation of important harmful aromatic compounds such as benzene, toluene, and xylene (BTX). The use of these compounds by both strains was determined as the production of cell mass (viable cell number) in a minimal medium containing any one of the BTX compounds as the sole carbon and energy source. Furthermore, the BTX degradation capability of both strains was monitored by measuring the production of 3‐methylcatechol, a common intermediate. For the cells of the logarithmic phase, which were grown at high aeration/high agitation or low aeration/low agitation, the engineered strain showed a better growth rate than the host strain. With the benzene in the medium, the recombinant strain exhibited a higher (up to 4‐fold) cell density than the parental wild‐type strain at this phase. In contrast, regarding the cells of the late stationary phase under high aeration/high agitation conditions, the host strain had generally higher viable cell numbers than the recombinant strain. At this phase this difference was, however, less significant under the conditions of low aeration/low agitation. Similarly, in toluene containing medium (at high aeration/high agitation) the recombinant strain showed a higher cell density which was from a 15‐fold to almost one order of magnitude greater than its parental strain during the logarithmic phase where the cell density of P. aeruginosa remained nearly constant. Contrary to the results with benzene and toluene, both strains exhibited similar growth characteristics when they were grown in the presence of xylene. The positive effect of the oxygen uptake by the recombinant system on the BTX metabolizing activity was also apparent in a high accumulation of 3‐methylcatechol in the cultures of the recombinant strain. At certain points of incubation, the hemoglobin expressing strain showed a significantly (p < 0.05) higher 3‐methylcatechol accumulation than the host strain. These results demonstrated the possible potential of the Vitreoscilla hemoglobin as an efficient oxygen uptake system for the bioremediation of some compounds of environmental concern.  相似文献   
70.
Incorporation of antioxidants into sunscreens is a logical approach, yet co-delivery of them with UV filters is a challenge. Here, we purposed a combination therapy, in which the chemical UV filter, octyl methoxycinnamate, was accumulated on upper skin while the antioxidant, melatonin, can penetrate deeper layers to show its effects. Melatonin-loaded elastic niosomes and octyl methoxycinnamate Pickering emulsion were prepared separately. Lyophilized elastic niosomes were dispersed into the Pickering emulsion to prepare the proposed combination formulation. The characterization studies of the formulations revealed that elastic niosomes can be prepared with tunable nanometer sizes, whereas Pickering emulsions can encapsulate the UV filter in micrometer-sized droplets. Melatonin-loaded elastic niosomes prepared with Tween80/Span80 mixture were 146 nm with a PI of 0.438, and 58.42% entrapment efficiency was achieved. The mean diameter size of the combination formulation was 27.8 μm. Ex vivo permeation studies revealed that 7.40% of octyl methoxycinnamate and 58% of melatonin were permeated through the rat skin while 27.6% octyl methoxycinnamate and 37% of melatonin accumulated in the skin after 24 h. Cell culture studies with real-time cell analyzer showed that the proposed formulation consist of melatonin-loaded elastic niosomes and octyl methoxycinnamate Pickering emulsion had no negative effect on the cell proliferation and viability. According to α,α-diphenyl-β-picrylhydrazyl free radical scavenging method, the proposed formulation showed as high antioxidant activity as melatonin itself. It is concluded that the proposed formulation would be a promising dual therapy for UV-induced skin damage with co-delivery strategy.  相似文献   
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