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51.
In experiments on dogs using the chemiluminescent method and nitroblue-tetrazole reaction the authors found out that leucocytes while passing through the pulmonary vessels bed, in contrast to the spleen increase the generation of active microbicidal forms of oxygen. Due to this fact we suppose that the lungs may take part in the formation of free radical status and phagocytic antiinfectious defence of the organism.  相似文献   
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Recently soluble CD163 (sCD163), a cleaved form of the macrophage receptor CD163, was identified as a macrophage-specific risk-predictor for developing Type 2 Diabetes. Here, we investigate circulating levels of sCD163 in gestational diabetes mellitus (GDM). Furthermore, given the role of the placenta in the pathogenesis of GDM, we assessed placental contribution to sCD163 secretion. Paired maternal (venous) and umbilical vein blood samples from GDM (n = 18) and Body Mass Index (BMI) matched control women (n = 20) delivered by caesarean section at 39–40 week gestation were assessed for circulating levels of sCD163, Tumour necrosis factor alpha (TNF-α) and Interleukin 6 (IL-6). Media from explant culture of maternal subcutaneous fat and corresponding placental tissues were assayed for these same molecules. CD163 positive cell numbers were determined in placental and adipose tissues of GDM and control women. We found significantly elevated circulating sCD163 levels in GDM mothers (688.4±46.9 ng/ml vs. 505.6±38.6 ng/ml) and their offspring (418.2±26.6 ng/ml vs. 336.3±24.4 ng/ml [p<0.05 for both]) as compared to controls, together with elevated circulating TNF-α and IL-6 levels. Moreover, both GDM placentae (268.1±10.8 ng/ml/mg vs. 187.6±20.6 ng/ml/mg) and adipose explants (41.1±2.7 ng/ml/mg vs. 26.6±2.4 ng/ml/mg) released significantly more sCD163 than controls. Lastly, significantly more CD163 positive cells were observed in GDM placentae (25.7±1.1 vs. 22.1±1.2) and adipose tissue (19.1±1.1 vs 12.7±0.9) compared to controls. We describe elevated sCD163 levels in GDM and identify human placenta as a novel source of sCD163 suggesting that placental tissues might contribute to the increased levels of circulating sCD163 in GDM pregnancies.  相似文献   
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Chagas’ disease, caused by the protozoan parasite Trypanosoma cruzi, affects 8–10 million people across the Latin American population and is responsible for around 12,500 deaths per annum. The current frontline treatments, benznidazole and nifurtimox, are associated with side effects and lack efficacy in the chronic stage of the disease, leading to an urgent need for new treatments. A high throughput screening campaign against the physiologically relevant intracellular form of the parasite identified a series of 2,4-diamino-6-methylpyrimidines. Demonstrating the series did not work through the anti-target TcCYP51, and was generally cytocidal, confirmed its suitability for further development. This study reports the optimisation of selectivity and metabolic stability of the series and identification of a suitable lead for further optimisation.  相似文献   
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The sulfated polysaccharides (SPs) from Chlamydomonas reinhardtii (Cr) were isolated by hot water method using 80% alcohol and semi purified by anion-exchange column chromatography. The chemical analysis of the extract showed 78% carbohydrates, 18% reducing sugars, 60% non-reducing sugars, 2% protein, 33% sulfate, 39% uronic acid, and 4% ash. The elemental analysis of this C. reinhardtii sulfated polysaccharide-enriched extract (Cr-SPs) showed 53% carbon, 8% hydrogen, and 6% nitrogen. FTIR analysis of Cr-SPs showed characteristic bands of sulfated polysaccharides. Further, the Cr-SPs showed significant hydroxyl radical scavenging activity of 22.29–80.9% at 0.01–1 mg mL?1, 38–77% of DPPH radical scavenging activity at 0.01–1 mg mL?1, 9.8–81% ABTS radical scavenging activity, 34.5–67.6% of ferrous chelating ability, and 11.62–75% of total antioxidant capacity. Cr-SPs also showed efficient in vitro anticancer activity. Specifically, they inhibited triple-negative breast cancer cell (MDA-MB-231) proliferation with an IC50 of 172 μg mL?1. Concentration-dependent reduction in the number of colonies formed by MDA-MB-231 cells suggested their potential to inhibit the clonal expansion of the cancer cells. Higher concentrations of crude extract were found to disrupt the microtubule networks in these cells. The cells treated with Cr-SPs eventually underwent apoptosis as evidenced by the formation of characteristic DNA ladder. These results indicate that Cr-SPs find promising opportunities for cancer treatment.  相似文献   
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Tracking changes in biodiversity through time requires an understanding of the relationship between modern diversity and how this diversity is preserved in the fossil record. Fossil pollen is one way in which past vegetation diversity can be reconstructed. However, there is limited understanding of modern pollen-vegetation diversity relationships from biodiverse tropical ecosystems. Here, pollen (palynological) richness and diversity (Hill N1) are compared with vegetation richness and diversity from forest and savannah ecosystems in the New World and Old World tropics (Neotropics and Palaeotropics). Modern pollen data were obtained from artificial pollen traps deployed in 1-ha vegetation study plots from which vegetation inventories had been completed in Bolivia and Ghana. Pollen counts were obtained from 15 to 22 traps per plot, and aggregated pollen sums for each plot were >?2,500. The palynological richness/diversity values from the Neotropics were moist evergreen forest?=?86/6.8, semi-deciduous dry forest?=?111/21.9, wooded savannah?=?138/31.5, and from the Palaeotropics wet evergreen forest?=?144/28.3, semi-deciduous moist forest?=?104/4.4, forest-savannah transition?=?121/14.1; the corresponding vegetation richness/diversity was 100/36.7, 80/38.7 and 71/39.4 (Neotropics), and 101/54.8, 87/45.5 and 71/34.5 (Palaeotropics). No consistent relationship was found between palynological richness/diversity, and plot vegetation richness/diversity, due to the differential influence of other factors such as landscape diversity, pollination strategy, and pollen source area. Palynological richness exceeded vegetation richness, while pollen diversity was lower than vegetation diversity. The relatively high global diversity of tropical vegetation was found to be reflected in the pollen rain.  相似文献   
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Protected areas such as forest reserves are often assumed to be best ways to conserve biodiversity and maintain intact ecosystems. We examined woody plant composition and diversity in the gallery forest and savannah woodland habitats of Amurum Forest Reserve and areas immediately surrounding it in Jos, Nigeria. A total of 100 10 × 10 m sample plots were established inside and outside the reserve. All woody plants ≥1 cm diameter at breast height (dbh) were identified and measured. A total of 7,564 individual plants categorized as 134 species from 44 families were recorded. Overall species diversity was significantly higher in the Forest Reserve than outside the reserve, although more species were encountered outside the reserve. Our findings suggest that, protected areas and the areas surrounding them are important for the conservation of biodiversity as the areas outside protected areas also contain species of conservation value. The continuous degrading areas outside protected areas isolates them and poses a serious threat to the long‐term viability of wildlife populations, so it is important that biodiversity in protected areas and their surrounding areas be conserved.  相似文献   
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