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991.
Yin‐Hui Zhao Cai‐Fu Shen Guang‐Jun Wang Yan Kang Yun‐Hong Song Jiang‐Wei Liu 《Journal of biochemical and molecular toxicology》2021,35(1)
Curcumin exhibits anti‐inflammatory and antioxidant activities. We investigated the protective effects of curcumin in a renal injury rat model under dry‐heat conditions. We divided Sprague‐Dawley rats into four groups: dry‐heat 0‐ (normal temperature control group), 50‐, 100‐, and 150‐minute groups. Each group was divided into five subgroups (n = 10): normal saline (NS), sodium carboxymethylcellulose (CMCNa), and curcumin pretreated low, medium, and high‐dose (50, 100, and 200 mg/kg, respectively) groups. Compared to the normal temperature group, serum creatinine, blood urea nitrogen, urinary kidney injury molecule‐1, and neutrophil gelatinase‐associated load changes in lipoprotein (NGAL) levels were significantly increased in the dry‐heat environment group (P < .05); inducible nitric oxide synthase (iNOS) and cyclooxygenase‐2 (COX‐2) expression and malondialdehyde (MDA) and related inflammatory factor levels were increased in the kidney tissue. Superoxide dismutase (SOD) and catalase (CAT) levels were decreased. However, following all curcumin pretreatment, the serum levels of kidney injury indicators and NGAL were decreased in the urine compared to those in the NS and CMCNa groups (P < .05), whereas renal SOD and CAT activities were increased and MDA was decreased (P < .05). Renal tissues of the 150‐minute group showed obvious pathological changes. Compared to the NS group, pathological changes in the renal tissues of the 100‐ and 200‐mg/kg curcumin groups were significantly reduced. Furthermore, iNOS and COX‐2 expression and inflammatory factor levels were decreased after curcumin treatment. Curcumin exerted renoprotective effects that were likely mediated by its antioxidant and anti‐inflammatory effects in a dry‐heat environment rat model. 相似文献
992.
Urban expansion can be seen as the most pervasive human impact on the environment where its high resource use contributes negatively to climate change and resource scarcity crises. Many experts call for decoupling resource use, economic development, and related urban development especially within cities of the Global South. This paper focuses on investigating resource efficiency through the lens of urban metabolism. It investigates current resource flows, through material flow analysis, from source to sink, in two diverse districts in Cairo: a formal district and an informal one, regarding materials (waste) and mobility. Consequently, the paper discusses locally responsive interventions that address local priorities as opposing to citywide one‐size fits all solution. The paper relies on parcel audits, which are embedded in an Urban Metabolism Information System developed by the Ecocity Builders and their partners, through a joint project with Cairo University. The methodology couples crowd‐sourced data, parcel audits, and experts’ knowledge to better understand resource flows based on a bottom‐up approach, given the unavailability of governmental data on the local level. The paper further correlates the perceived quality of life with the actual resource flows. It utilizes fieldwork investigations to argue against the local misconceptions regarding the inefficiency of informal areas/systems versus the higher efficiency of planned areas/systems. The paper concludes by proposing integrated solutions that respond to local needs and resources. It highlights the challenges and lessons of this tailored bottom‐up approach and its applicability in other cities worldwide. 相似文献
993.
Distinctive probiotic features share common TLR2‐dependent signalling in intestinal epithelial cells
Diana Paveljek Karolina Ivi
ak‐Kocjan Primo Treven Mojca Ben
ina Roman Jerala Irena Rogelj 《Cellular microbiology》2021,23(1)
The underlying mechanisms of probiotics and postbiotics are not well understood, but it is known that both affect the adaptive and innate immune responses. In addition, there is a growing concept that some probiotic strains have common core mechanisms that provide certain health benefits. Here, we aimed to elucidate the signalization of the probiotic bacterial strains Lactobacillus paragasseri K7, Limosilactobacillus fermentum L930BB, Bifidobacterium animalis subsp. animalis IM386 and Lactiplantibacillus plantarum WCFS1. We showed in in vitro experiments that the tested probiotics exhibit common TLR2‐ and TLR10‐dependent downstream signalling cascades involving inhibition of NF‐κB signal transduction. Under inflammatory conditions, the probiotics activated phosphatidylinositol 3‐kinase (PI3K)/Akt anti‐apoptotic pathways and protein kinase C (PKC)‐dependent pathways, which led to regulation of the actin cytoskeleton and tight junctions. These pathways contribute to the regeneration of the intestinal epithelium and modulation of the mucosal immune system, which, together with the inhibition of canonical TLR signalling, promote general immune tolerance. With this study we identified shared probiotic mechanisms and were the first to pinpoint the role of anti‐inflammatory probiotic signalling through TLR10. 相似文献
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BackgroundWe investigated the relationship between genetic alterations and 18F-FDG PET/CT findings in head and neck squamous cell carcinoma (HNSC).MethodsUsing mRNA-sequences of HNSC samples (480 patients) from the Cancer Genome Atlas (TCGA) portal, gene coexpression networks were constructed via a weighted correlation network analysis (WGCNA) algorithm, and their association with the tumor-to-blood signal ratio on 18F-FDG PET/CT data (21 patients) was explored. An elastic-net regression model was developed to estimate the PET tumor-to-blood ratio from the gene networks and to derive an FDG signature score (FDGSS). The FDGSS was evaluated with regard to clinical variables and general mutational profiles, as well as alterations to oncogenic signaling pathways.FindingsThe FDGSS values differed across clinical stages (p = 0.027), HPV-status (p< 0.001), and molecular subtypes of HNSC (p< 0.001). Multivariate Cox regression demonstrated that FDGSS was an independent predictor for overall (p = 0.019) and progression-free survival (p = 0.024). FDGSS positively correlated with total mutation rate (p = 0.016), aneuploidy (p < 0.001), and somatic copy number alteration scores (p < 0.001). CDKN2A in the cell cycle pathway (q = 0.014) and the TP53 gene in the TP53 pathway (q = 0.005) showed significant differences between high and low FDGSS patients.ConclusionFDGSS based on the gene coexpression network was associated with the mutational landscape of HNSC. 18F-FDG PET/CT is therefore a valuable tool for the in vivo imaging of these cancers, being able to visualize the glucose metabolism of the tumor and allow inferences to be made on the underlying genetic alterations in the tumor. 相似文献
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Jean‐Pierre Desforges Floris M. van Beest Gonalo M. Marques Stine H. Pedersen Larissa T. Beumer Marianna Chimienti Niels Martin Schmidt 《Ecology and evolution》2021,11(1):338-351
Animals have adapted behavioral and physiological strategies to conserve energy during periods of adverse conditions. Heterothermy is one such adaptation used by endotherms. While heterothermy—fluctuations in body temperature and metabolic rate—has been shown in large vertebrates, little is known of the costs and benefits of this strategy, both in terms of energy and in terms of fitness. Hence, our objective was to model the energetics of seasonal heterothermy in the largest Arctic ungulate, the muskox (Ovibos moschatus), using an individual‐based energy budget model of metabolic physiology. We found that the empirically based drop in body temperature (winter max ~−0.8°C) overwinter in adult females resulted in substantial fitness benefits in terms of reduced daily energy expenditure and body mass loss. Body mass and energy reserves were 8.98% and 14.46% greater in modeled heterotherms compared to normotherms by end of winter. Based on environmental simulations, we show that seasonal heterothermy can, to some extent, buffer the negative consequences of poor prewinter body condition or reduced winter food accessibility, leading to greater winter survival (+20%–30%) and spring energy reserves (+10%–30%), and thus increased probability of future reproductive success. These results indicate substantial adaptive short‐term benefits of seasonal heterothermy at the individual level, with potential implications for long‐term population dynamics in highly seasonal environments. 相似文献
999.
Sunghyun Woo Dongyeob Lee Yong‐Chan Cho Sangsun Lee Eunsuk Kim 《Ecology and evolution》2021,11(1):516-525
Comparative studies of invasive, noninvasive alien, and native congenic plant species can identify plant traits that drive invasiveness. In particular, functional traits associated with rapid growth rate and high fecundity likely facilitate invasive success. As such traits often exhibit high phenotypic plasticity, characterizing plastic responses to anthropogenic environmental changes such as eutrophication and disturbance is important for predicting the invasive success of alien plant species in the future. Here, we compared trait expression and phenotypic plasticity at the species level among invasive, noninvasive alien, and native Bidens species. Plants were grown under nutrient addition and competition treatments, and their functional, morphological, and seed traits were examined. Invasive B. frondosa exhibited higher phenotypic plasticity in most measured traits than did the alien noninvasive B. pilosa or native B. bipinnata. However, differential plastic responses to environmental treatments rarely altered the rank of trait values among the three Bidens species, except for the number of inflorescences. The achene size of B. frondosa was larger, but its pappus length was shorter than that of B. pilosa. Two species demonstrated opposite plastic responses of pappus length to fertilization. These results suggest that the plasticity of functional traits does not significantly contribute to the invasive success of B. frondosa. The dispersal efficiency of B. frondosa is expected to be lower than that of B. pilosa, suggesting that long‐distance dispersal is likely not a critical factor in determining invasive success. 相似文献
1000.
利用生物信息学方法,从茶树(Camellia sinensis(L.)O.Ktze.)全基因组数据库中分析获得DELLA蛋白的家族成员,并对它们的系统进化关系、蛋白序列特征、基因表达特异性及其与茶树次生代谢物的相关性进行分析。结果显示:茶树基因组中共有5个DELLA基因,分别为:TEA009882(CsGAI)、TEA022818(CsRGA1)、TEA010112(CsRGL1)、TEA008736(CsRGL2)和TEA020933(CsRGL3);其编码的氨基酸数量在525~594之间,均定位于细胞核。该蛋白的二级和三级结构分析结果表明,茶树DELLA蛋白结构中含有大量的α螺旋及少量β转角结构。蛋白保守结构域分析结果显示该蛋白与拟南芥(Arabidopsis thaliana(L.)Heynh.)具有高度的同源性,均具有GRAS、DELLA等保守结构域。基因的表达特异性分析结果表明,在茶树不同组织部位中,TEA009882、TEA022818和TEA010112基因的表达量均较高,而TEA020933和TEA008736的表达量在各组织中均较低;茶树DELLA基因的表达受到干旱、NaCl、低温及茉莉酸甲酯等非生物逆境胁迫的调控,且其表达量与茶树次生代谢物的积累间存在相关性。推测茶树DELLA基因广泛参与了茶树生长发育及非生物逆境胁迫的响应,以及对次生代谢物生物合成过程的调控。 相似文献