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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.
993.
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
994.
This study investigated the effect of adult associated cues of the multicolored Asian ladybird Harmonia axyridis Pallas (Coleoptera: Coccinellidae) on the foraging behavior of the aphid parasitoid, Aphidius gifuensis Ashmead (Hymenoptera: Aphididae) with three assays: 1) whole aphid leaf-disc with H. axyridis tracks; 2) aphid leaf-disc with only half contaminated with H. axyridis tracks; 3) aphid leaf-discs without H. axyridis tracks. Foraging behavior of A. gifuensis was recorded using the Observer® XT 11 and EthoVsion® XT 12. In addition, functional responses of A. gifuensis in patches with or without H. axyridis cues were also tested. Aphidius gifuensis females preferred oviposition in arenas where no adult tracks of H. axyridis were present. However, no significant difference between functional responses of A. gifuensis foraging in plants with and without H. axyridis cues was detected. Our study suggests that H. axyridis associated cues could influence the foraging behavior and activity of A. gifuensis under laboratory conditions. On the other hand, the foraging efficiency of A. gifuensis was not significantly affected by H. axyridis walking tracks in a single plant system. Aphidius gifuensis might exhibit flexible behavioral responses to predator associated cues. The risk of intraguild interactions and the possibility of mitigating such risks for parasitoids are important components for ultimately determining the compatibility of biological control agents. 相似文献
995.
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
996.
Yumin Wang Luyuan Zhang Yi Yang Shan Lu Hao Chen 《International journal of biological sciences》2021,17(4):1041
With the development of genomics, the update of modern imaging technology and the advent of artificial intelligence and big data, the surgical treatment of gastric cancer has gradually stepped into precision medicine. Precision surgery treatment of gastric cancer is based on accurate molecular typing and staging using modern molecular diagnostic technology and imaging, and the formulation of precise and individualized surgical treatment plans, with the concept of minimally invasive and accelerated rehabilitation surgery running through it. For intermediate-stage gastric cancer, we have adopted a comprehensive treatment approach including traditional radiotherapy and chemotherapy, targeted therapy and immunotherapy. Utilize artificial intelligence and big data technology to improve the standardization and interconnectivity of specialty data and realize the transformation of evidence-based medicine. Promoting the standardization, standardization and individualization of gastric cancer surgical treatment, providing patients with precise diagnosis and treatment, and further improving patients'' prognosis are the opportunities and challenges in the development of gastric cancer surgery. 相似文献
997.
998.
Ping Liu Ruichao Niu Jie Chen Yuling Tang Wenfang Tang Linyan Xu Juntao Feng 《PLoS neglected tropical diseases》2021,15(3)
ObjectivesIn December 2019, coronavirus disease 2019 (COVID-19) emerged in Wuhan City and rapidly spread across the world. The clinical characteristics of affected patients in different regions and populations may differ. Thus, this study aimed to identify the characteristics of the disease to provide an insight about the prevention and treatment of COVID-19.MethodsData on the demographic characteristics and clinical findings of the patients admitted at the First Hospital of Changsha from January 1, 2020 to February 10, 2020 were assessed.ResultsIn this study, there were 8 (3.8%) asymptomatic, 21 (10.0%) mild upper respiratory tract infection (URTI), and 180 (86.1%) pneumonia cases. In total, 47 (22.5%) patients resided in Wuhan, and 45 (21.5%) had recently traveled to Wuhan before disease onset. Moreover, 19 (9.1%) had contact with people from Wuhan, and 69 (33.0%) were family cluster cases. The median incubation period was approximately 6.3 (range: 1.0–20.0) days. Fever and cough were the most common initial symptoms: 99 (49.3%) patients presented with fever, without cough; 59 (29.4%) with cough, without fever; and 33 (16.4%) with both fever and cough.ConclusionThe symptoms of patients with COVID-19 were relatively mild outside Wuhan, and family cluster was a remarkable epidemic characteristic. Special attention should be paid to asymptomatic patients. 相似文献
999.
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
1000.
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