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151.
Yun Chan Jung Mi Eun Kim Ju Hwa Yoon Pu Reum Park Hwa-Young Youn 《Immunopharmacology and immunotoxicology》2014,36(6):426-432
Inflammation is the major symptom of the innate immune response to microbial infection. Macrophages, immune response-related cells, play a role in the inflammatory response. Galangin is a member of the flavonols and is found in Alpinia officinarum, galangal root and propolis. Previous studies have demonstrated that galangin has antioxidant, anticancer, and antineoplastic activities. However, the anti-inflammatory effects of galangin are still unknown. In this study, we investigated the anti-inflammatory effects of galangin on RAW 264.7 murine macrophages. Galagin was not cytotoxic to RAW 264.7 cells, and nitric oxide (NO) production induced by lipopolysaccharide (LPS)-stimulated macrophages was significantly decreased by the addition of 50?μM galangin. Moreover, galangin treatment reduced mRNA levels of cytokines, including IL-1β and IL-6, and proinflammatory genes, such as iNOS in LPS-activated macrophages in a dose-dependent manner. Galangin treatment also decreased the protein expression levels of iNOS in activated macrophages. Galangin was found to elicit anti-inflammatory effects by inhibiting ERK and NF-κB-p65 phosphorylation. In addition, galangin-inhibited IL-1β production in LPS-activated macrophages. These results suggest that galangin elicits anti-inflammatory effects on LPS-activated macrophages via the inhibition of ERK, NF-κB-p65 and proinflammatory gene expression. 相似文献
152.
Jafar Soltani Bahram Nikkhoo Jabar Khormehr Pedram Ataee Mohammad-Saeid Hakhamaneshi Fardin Gharibi 《Iranian journal of pediatrics.》2014,24(6):745-752
Objective:
Helicobacter pylori (H. pylori) is the most common chronic bacterial infection in humans. Chronic colonization increases the risk of duodenal ulcer and gastric cancer. The risk factors for acquiring the infection have been extensively studied. However, there are conflicting results on the role of breastfeeding in the prevention of H. pylori infection. We conducted a study to evaluate the effects of breastfeeding on the H. Pylori infection in Kurdish children in Sanandaj, IR Iran.Methods:
A historical cohort study was carried out from January 2011 through December 2012. Totally 221 children who were going to attain 2 years old during the study period were randomly enrolled. They were divided into two groups, i.e. breastfed and non-breastfed. We used H. pylori stool antigen test to detect infection in the selected group of children after age of 2 years and cessation of breastfeeding. Each group was subdivided into two subgroups, infected and non-infected. The associations of breastfeeding with H. pylori infection was assessed using statistical software.Findings:
We found no difference in the odds of infection between breastfed and non-breastfed groups (OR=0.809, 95% CI [0.453–1.444]). An association between age and the prevalence of infection was found (P=0.008). There was an increase in the odds of infection as the family size grew (OR=1.93, 95% CI [1.04–3.6]) as well as increasing housing density (OR=2.12, 95% CI [1.10–4.10]).Conclusion:
The data suggests that breastfeeding in infancy does not protect against H. pylori infection for long duration among studied children in Iran. The protective effects of breastfeeding, if any, are at most transient. 相似文献153.
《Seminars in immunology》2014,26(2):114-126
Bone marrow-derived natural killer (NK) cells constitute the major subset of cytotoxic lymphocytes in peripheral blood. They provide innate defense against intracellular infection or malignancy and contribute to immune homeostasis. Large numbers of NK cells are also present in tissues, including the liver and uterus, where they can mediate immunosurveillance but also play important roles in tissue remodeling and vascularization. Here, we review the pathways involved in NK cell lineage commitment and differentiation, discussing relationships to other lymphocyte populations and highlighting genetic determinants. Characterizing NK cells from distinct tissues and during infections have revealed subset specializations, reflecting inherent cellular plasticity. In this context, we discuss how different environmental and inflammatory stimuli may shape NK cells. Particular emphasis is placed on genes identified as being critical for NK cell development, differentiation, and function from studies of model organisms or associations with disease. Such studies are also revealing important cellular redundancies. Here, we provide a view of the genetic framework constraining NK cell development and function, pinpointing molecules required for these processes but also underscoring plasticity and redundancy that may underlie robust immunological function. With this view, built in redundancy may highlight the importance of NK cells to immunity. 相似文献
154.
Vivek K.Bajpai Jung In Yoon Monika Bhardwaj Sun Chul Kang 《Asian Pacific journal of tropical medicine》2014,7(8):602-608
Objective:To examine the individual and synergistic anti-listcrial effect of nisin and leaf essential oil of Metasequoia glyptostroboides(M.glyptostroboides) against one of the leading foodhorne pathogens Listeria monocytogenes(L.monocytogenes) ATCC 19116 in milk samples.Methods:The whole(8%),low(1%) and skim(no fat content) milk samples were inoculated with L.monocytogenes ATCC 19116 along with leaf essential oil of M.glyptostroboides or nisin alone as well in eomhinations.Results:In this study,the leaf essential oil at the concentrations of 2% and 5% revealed strong anti-listerial effect against L.monocytogenes ATCC 19116 in all categories of milk samples.Nisin at the concentrations of 250 and 500 IU/mL displayed a strong inhibitory effect against ATCC 19116 as compared to the control group.Additionally,synergistic combinations of leaf essential oil(1%) and nisin(62.5,125.250 and 500 IU/mL) also had a remarkable anti-listerial synergism in all the tested milk samples including whole,low and skim milk after 14 days.Conclusions:As a major finding,the leaf essential oil of M.glyptostroboides might he a useful candidate for using in food industry to control the growth of foodhorne pathogenic bacteria as confirmed by its potent anti-listerial Synergistic effect with nisin against L.monocytogenes ATCC 19116 in different milk samples. 相似文献
155.
Frank Bruchertseifer Alban Kellerbauer Rikard Malmbeck Alfred Morgenstern 《Journal of labelled compounds & radiopharmaceuticals》2019,62(11):794-802
Targeted alpha therapy (TAT) is a promising approach for the treatment of cancer. The use of alpha emitters for cancer therapy has two distinct advantages over conventional therapies. The short range of alpha radiation in human tissue (less than 0.1 mm), corresponding to only a few cell diameters, allows selective killing of targeted cancer cells while sparing surrounding healthy tissue. At the same time, the high energy (several MeV) of alpha radiation and its associated high linear energy transfer leads to highly effective cell kill. Consequently, alpha radiation can destroy cells which otherwise exhibit resistance to treatment with beta or gamma irradiation or chemotherapeutic drugs, and can thus offer a therapeutic option for tumors resistant to conventional therapies. Recent results demonstrating the remarkable therapeutic efficacy of alpha emitters to treat various cancers have underlined the clinical potential of TAT. This paper describes the recent clinical experience with 213Bi and 225Ac. In view of the enormous benefit of targeted cancer treatment with alpha emitters, their production will have to be considerably increased beyond current supply capabilities. Alternative production methods based on the irradiation of uranium, thorium, or radium targets at reactors or accelerator facilities have the potential to meet future demand. 相似文献
156.
157.
158.
Introduction
The natural history of acute pulmonary embolism (PE) under treatment is about a gradual resolution of the thrombi, and uncommonly, the development of chronic thromboembolic pulmonary hypertension (CTEPH). We hypothesized that ventilatory efficiency parameters during cardiopulmonary exercise testing (CPET) may be able to monitor the process and predict CTEPH.Methods
15 patients rehabilitated from acute PE (total resolution of thrombi), 44 patients with chronic PE (with residual thrombi), 66 patients with CTEPH, and 36 sedentary healthy controls performed incremental CPET.Results
The lowest VE/VCO2 was higher in CTEPH patients than that in chronic PE and rehabilitated patients (43.4 L/min vs 29.9 L/min vs 27.1 L/min, p < 0.005). The VE/VCO2 slope (48.4 L/min/L/min vs 29.9 L/min/L/min vs 28.0 L/min/L/min, p < 0.005) and oxygen uptake efficiency plateau (OUEP) (37.1 L/min vs 27.0 L/min vs 25.2 L/min, p < 0.005) had the similar changes. In logistic regression analysis, the lowest VE/VCO2 ≥ 34.35 L/min was the best predictor of CTEPH (OR 159.0, 95% CI 36.0-702.3, p < 0.001). The lowest VE/VCO2 was higher in chronic PE patients compared with the controls (29.9 L/min vs 26.5 L/min, p < 0.05), but there was no difference between the rehabilitated patients and the controls. In multiple linear regression analysis, the percentage of vascular obstruction by ventilation-perfusion lung scanning (PVO) was the most significant independent predictor for indices of ventilatory efficiency in chronic PE and rehabilitated patients.Conclusions
CTEPH is associated with weakened ventilatory efficiency. The lowest VE/VCO2 ratio has the best capability to predict CTEPH. Ventilatory inefficiency improves along with recovery of acute PE. 相似文献159.
Xu B Bhawe Y Davis ME 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(24):9260-9264
Thermochemical cycles that split water into stoichiometric amounts of hydrogen and oxygen below 1,000 °C, and do not involve toxic or corrosive intermediates, are highly desirable because they can convert heat into chemical energy in the form of hydrogen. We report a manganese-based thermochemical cycle with a highest operating temperature of 850 °C that is completely recyclable and does not involve toxic or corrosive components. The thermochemical cycle utilizes redox reactions of Mn(II)/Mn(III) oxides. The shuttling of Na(+) into and out of the manganese oxides in the hydrogen and oxygen evolution steps, respectively, provides the key thermodynamic driving forces and allows for the cycle to be closed at temperatures below 1,000 °C. The production of hydrogen and oxygen is fully reproducible for at least five cycles. 相似文献
160.
Residual soil phosphorus as the missing piece in the global phosphorus crisis puzzle 总被引:10,自引:0,他引:10
Sattari SZ Bouwman AF Giller KE van Ittersum MK 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(16):6348-6353
Phosphorus (P) is a finite and dwindling resource. Debate focuses on current production and use of phosphate rock rather than on the amounts of P required in the future to feed the world. We applied a two-pool soil P model to reproduce historical continental crop P uptake as a function of P inputs from fertilizer and manure and to estimate P requirements for crop production in 2050. The key feature is the consideration of the role of residual soil P in crop production. Model simulations closely fit historical P uptake for all continents. Cumulative inputs of P fertilizer and manure for the period 1965-2007 in Europe (1,115 kg . ha(-1) of cropland) grossly exceeded the cumulative P uptake by crops (360 kg ha(-1)). Since the 1980s in much of Europe, P application rates have been reduced, and uptake continues to increase due to the supply of plant-available P from residual soil P pool. We estimate that between 2008 and 2050 a global cumulative P application of 700-790 kg . ha(-1) of cropland (in total 1,070-1,200 teragrams P) is required to achieve crop production according to the various Millennium Ecosystem Assessment scenarios [Alcamo J, Van Vuuren D, Cramer W (2006) Ecosystems and Human Well-Being: Scenarios, Vol 2, pp 279-354]. We estimate that average global P fertilizer use must change from the current 17.8 to 16.8-20.8 teragrams per year in 2050, which is up to 50% less than other estimates in the literature that ignore the role of residual soil P. 相似文献