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121.
Biological Invasions - As the number of non-native species introductions continues to increase, the need for tools to predict potential invaders is a central focus in invasion ecology. Trait-based...  相似文献   
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The genus Dorema (Apiaceae) comprises 12 accepted species, mainly growing in Asia and, particularly, in Iran, where D. ammoniacum and D. aucheri are the most used species in cuisine and folk medicine. The Dorema species are traditionally applied in the treatment of catarrh, asthma, chronic bronchitis, as carminative, mild diuretic and anthelmintic agents. In general, 42 non-volatile secondary metabolites were isolated from the 6 studied species, namely D. aitchisonii, D. ammoniacum, D. aucheri, D. glabrum, D. hyrcanum, and D. kopetdaghense. Among them, phenolic acid, flavonoid, acetophenone, coumarin, and sesquiterpene derivatives were identified as the predominant phytoconstituents. The leaves are characterized by the highest volatile content, and the sesquiterpenes in both hydrocarbon and oxygenated forms were reported as the most abundant compounds. Most of the studied pharmacological activities were assessed in vivo. Nevertheless, in vitro antiradical and antimicrobial potentials were the main investigated activities. Overall, the evaluation of bioactivities confirmed the ethnopharmacological use of the Dorema species, particularly their anti-inflammatory, antibacterial, and hypolipidemic properties. This study comprehensively overviewed, for the first time, the literature relating to the folk medicinal use and to the available phytochemical and pharmacological data. Considering the genus application and the rare clinical trials, the study of the efficacy and safety of the uninvestigated Dorema species might be an interesting and promising approach for further researches.

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BackgroundHigh tumor infiltrating lymphocytes (TILs) density was previously shown to be associated with favorable prognosis for patients with colon cancer (CC). However, the impact of TILs on overall survival (OS) of stage II CC patients who received adjuvant chemotherapy (ADJ) or not (no-ADJ) is unknown. We assessed the prognostic value of CD3+ TILs in stage II CC patients according to whether they had ADJ or not.MethodsPatients treated with curative surgery for stage II CC (2002–2013) were selected from the Santa Maria alle Scotte Hospital registry. TILs at the invasive front, center of tumor, and stroma were determined by immunohistochemistry and manually quantified as the rate of TILs/total tissue areas. High TILs (H-TILs) was defined as >20%. Patients were categorized as high or low TILs (L-TILs) and ADJ or no-ADJ.ResultsOf the 678 patients included, 137 (20%) received ADJ and 541 (80%) did not. The distribution of the 4 groups were: 16% (L-TIL/ADJ), 64% (L-TIL/no-ADJ), 5% (H-TIL/ADJ), 15% (H-TIL/no-ADJ). Compared to H-TILs/no-ADJ, ADJ patients showed a significantly increased OS (P<.01) regardless of the TILs rate whereas L-TILs/no-ADJ had significantly decreased OS and higher risk of death (HR=1.41; 95% CI, 1.06–1.88; P<.0001). On multivariable analysis, the unfavorable prognostic value of L-TILs (vs. H-TILs) for no-ADJ patients was confirmed (HR=1.36; 95% CI 1.02, 1.82; P=.0373).ConclusionLow CD3+ TILs rate was associated with shorter OS in those with stage II colon cancer who did not receive adjuvant therapy. Low CD3+ TILs could be considered an additional risk factor for still ADJ-untreated stage II CC patients, which could facilitate clinical decision making.  相似文献   
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Abstract

The need to optimize seed banking efforts has stimulated research for rapid methods to estimate quality in seed-lots. For terrestrial orchids, viability testing using tetrazolium (TTC) staining requires chemical scarification, as seeds have an impermeable testa. Different seed-coat permeability may affect TTC staining, thus affecting the results. The aim of this study was to perform a permeability test to assess the effectiveness of the used scarification method and its usefulness to correct TTC viability results. Mature seeds of Anacamptis laxiflora were subjected to eight scarification treatments with sodium hypochlorite solutions with different concentration and duration. Viability tests were performed using the basic TTC methodology, followed by a permeability test performed by means of trypan blue dye. The different scarification methods resulted in estimated TTC viability ranging from 0% and 94% for the same seed lot of A. laxiflora seeds. Our results proved that the used scarification protocol significantly affects both seed coat permeability and subsequent TTC staining (two-way ANOVA, p?< 0.0001). We describe a new rapid protocol that can be used to test terrestrial orchid seed viability. This double-staining method, providing rapid information on seed coat permeability, can be useful to avoid under-estimation of TTC results.  相似文献   
126.
A major difficulty in addressing chemical mixtures through legislation or regulations revolves around our limited understanding of their potential impacts. This review provides an overview of recent research on pesticide mixture toxicity to aquatic biota and the methods employed to predict toxic effects. The most common approaches are to assume concentration-addition or independent action of chemicals in a mixture. There are a number of cases in the literature of interactions between pesticides. However, models accounting for possible interactions between mixture components are used infrequently. Although results are limited, studies investigating the effects of pesticide mixtures have not demonstrated significant synergism at environmentally relevant concentrations. Based on the results of our review, we conclude that the concentration-addition model is a generally conservative and practical first-tier model for the ecological assessment of pesticide mixtures in aquatic systems.  相似文献   
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Ischemic stroke is confounded by conditions such as atherosclerosis, diabetes, and infection, all of which alter peripheral inflammatory processes with concomitant impact on stroke outcome. The majority of the stroke patients are elderly, but the impact of interactions between aging and inflammation on stroke remains unknown. We thus investigated the influence of age on the outcome of stroke in animals predisposed to systemic chronic infection. Th1‐polarized chronic systemic infection was induced in 18–22 month and 4‐month‐old C57BL/6j mice by administration of Trichuris muris (gut parasite). One month after infection, mice underwent permanent middle cerebral artery occlusion and infarct size, brain gliosis, and brain and plasma cytokine profiles were analyzed. Chronic infection increased the infarct size in aged but not in young mice at 24 h. Aged, ischemic mice showed altered plasma and brain cytokine responses, while the lesion size correlated with plasma prestroke levels of RANTES. Moreover, the old, infected mice exhibited significantly increased neutrophil recruitment and upregulation of both plasma interleukin‐17α and tumor necrosis factor‐α levels. Neither age nor infection status alone or in combination altered the ischemia‐induced brain microgliosis. Our results show that chronic peripheral infection in aged animals renders the brain more vulnerable to ischemic insults, possibly by increasing the invasion of neutrophils and altering the inflammation status in the blood and brain. Understanding the interactions between age and infections is crucial for developing a better therapeutic regimen for ischemic stroke and when modeling it as a disease of the elderly.  相似文献   
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