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1.
The cellular energy and biomass demands of cancer drive a complex dynamic between uptake of extracellular FAs and their de novo synthesis. Given that oxidation of de novo synthesized FAs for energy would result in net-energy loss, there is an implication that FAs from these two sources must have distinct metabolic fates; however, hitherto, all FAs have been considered part of a common pool. To probe potential metabolic partitioning of cellular FAs, cancer cells were supplemented with stable isotope-labeled FAs. Structural analysis of the resulting glycerophospholipids revealed that labeled FAs from uptake were largely incorporated to canonical (sn-) positions on the glycerol backbone. Surprisingly, labeled FA uptake also disrupted canonical isomer patterns of the unlabeled lipidome and induced repartitioning of n-3 and n-6 PUFAs into glycerophospholipid classes. These structural changes support the existence of differences in the metabolic fates of FAs derived from uptake or de novo sources and demonstrate unique signaling and remodeling behaviors usually hidden from conventional lipidomics.  相似文献   
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Human placental protein 14 (PP14) has been purified in high yield from first trimester decidual cytosol. High-performance liquid chromatography on anion exchange, gel filtration and reverse-phase chromatography were used. The protein obtained is approximately 97% pure with an overall recovery of about 50% from the original tissue extract. The first 24 amino acids of the N-terminal were found to be Met-Asp-Ile-Pro-Gln-Thr-Lys-Gln-Asp-Leu-Glu-Leu-Pro-Lys-Leu-Ala-Gly-Thr-Glu-His - Glu-Met-Ala-Met. PP14 has been characterized in this study to be a dimeric glycoprotein of Mr 60,000, with homologous subunits having an Mr of 28,000.  相似文献   
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Two dogs were prepared with Pavlov pouches of the fundic area of the stomach using standard techniques. During treatment periods of 14 days, 200 mg acetylsalicylic acid (ASA) was introduced into the pouch twice daily by insufflation. One hour after each drug administration the pouch was washed with saline and the fluid assayed for blood. Bleeding from the pouch increased to a maximum on the 3rd or 4th day of the treatment period and subsequently declined such that by the 8th day blood loss was minimal and approximated that found during control periods. Platelet aggregation (in vitro) responses to adenosine diphosphate were significantly (p less than 0.01) inhibited on day 3 when aggregation curve heights were reduced by 66.2 +/- 13.11% (mean +/- SEM) from control values. On day 7 and during the ensuing 7-day period when ASA was given twice daily, the heights of aggregation responses were reduced by only 20-30% from controls. These responses were significantly (p less than 0.001) greater than those found on day 3. Similar changes in platelet reactivity were found in plasma from rats given ASA twice daily for 7 days. Aggregation responses to collagen were depressed by 95.5 +/- 4.49% on day 1 following two doses of ASA. As the treatment period continued, the aggregation responses increased in magnitude until the 7th day they were similar in height to those from control animals. The mechanism involved in this adaptation to ASA treatment seen with these platelets is not known.  相似文献   
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Plant and Soil - Perennial forage grass production has the potential to improve smallholder livelihoods in the tropics. However, nutrient management is often challenging, especially on infertile...  相似文献   
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A thymic epithelial cell line (tsTNC-1) that maintains the ability to selectively bind and internalize immature alphabetaTCR(lo)CD4(+)CD8(+) thymocytes in vitro was used in long-term coincubation experiments to determine the ultimate fate of thymocytes that remained within intracytoplasmic vacuoles of thymic nurse cells (TNCs). In an earlier report, a subset of the population released from the TNC interaction was shown to mature to the alphabetaTCR(hi)CD69(hi) stage of development, while thymocytes that bided within the TNC cytoplasm died through the process of apoptosis. Here, we show the presence of both apoptotic and nonapoptotic thymocytes within the cytoplasm of freshly isolated TNCs as well as in tsTNC-1 cells in culture. A microscopic analysis revealed total degradation of the cytoplasmic apoptotic thymocyte population that remained in tsTNC-1 cells after an 8- to 10-h incubation period. A quantitative analysis showed an increase of cytoplasmic thymocyte degradation over time to almost 80% after 9 h of incubation. However, in the presence of bafilomycin A1, which is used to inhibit acidification of lysosomal vesicles, degradation of apoptotic thymocytes never reached 10%. These data suggest that lysosomes within TNCs play a role in the degradation of apoptotic thymocytes. We examined tsTNC-1 cells before the addition of thymocytes to cultures and found lysosomes to be clustered around the nucleus in the cytoplasm of TNCs. Shortly after the internalization event, apoptotic thymocytes move to the area of the cytoplasm containing lysosomes. Using the confocal microscope, we obtained evidence that shows the degradation event to be facilitated through the fusion of lysosomes with the specialized vacuoles within TNCs containing apoptotic cells.  相似文献   
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BACKGROUND: Morbidity management is a core component of the global programme for the elimination of lymphatic filariasis. In a double-blind clinical trial, the tolerability and efficacy of Daflon (500 mg) + DEC (25 mg) or DEC (25 mg) alone, twice daily for 90 days, was studied in 26 patients with bancroftian filarial lymphoedema. RESULTS: None of the patients in either drug group reported any adverse reaction throughout the treatment period (90 days). Haematological and biochemical parameters were within normal limits and there was no significant difference between the pre-treatment (day 0) and post-treatment (day 90) values. The group receiving Daflon showed significant reduction in oedema volume from day 90 (140.6 PlusMinus; 18.8 ml) to day 360 (71.8 PlusMinus; 20.7 ml) compared to the pre-treatment (day 0, 198.4 PlusMinus; 16.5 ml) value. This accounted for a 63.8% reduction in oedema volume by day 360 (considering the pre-treatment (day 0) as 100%). In the DEC group, the changes in oedema volume (between day 1 and day 360) were not significant when compared to the pre-treatment (day 0) value. The percentage reduction at day 360 was only 9%, which was not significant (P > 0.05). CONCLUSION: This study has shown that Daflon (500 mg, twice a day for 90 days) is both safe and efficacious in reducing oedema volume in bancroftian filarial lymphoedema. Further clinical trials are essential for strengthening the evidence base on the role of this drug in the morbidity management of lymphatic filariasis.  相似文献   
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The development of new therapeutic strategies is necessary to reduce the worldwide social and economic impact of cardiovascular disease, which produces high rates of morbidity and mortality. A therapeutic option that has emerged in the last decade is cell therapy. The aim of this study was to compare the effect of transplanting human umbilical cord-derived stromal cells (UCSCs), human umbilical cord blood-derived endothelial cells (UCBECs) or a combination of these two cell types for the treatment of ischemic cardiomyopathy (IC) in a Wistar rat model. IC was induced by left coronary artery ligation, and baseline echocardiography was performed seven days later. Animals with a left ventricular ejection fraction (LVEF) of ≤40% were selected for the study. On the ninth day after IC was induced, the animals were randomized into the following experimental groups: UCSCs, UCBECs, UCSCs plus UCBECs, or vehicle (control). Thirty days after treatment, an echocardiographic analysis was performed, followed by euthanasia. The animals in all of the cell therapy groups, regardless of the cell type transplanted, had less collagen deposition in their heart tissue and demonstrated a significant improvement in myocardial function after IC. Furthermore, there was a trend of increasing numbers of blood vessels in the infarcted area. The median value of LVEF increased by 7.19% to 11.77%, whereas the control group decreased by 0.24%. These results suggest that UCSCs and UCBECs are promising cells for cellular cardiomyoplasty and can be an effective therapy for improving cardiac function following IC.  相似文献   
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