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Calcium sulfoaluminate‐based cements (CSA) are proposed as a cement alternative with a low carbon footprint. The nature of CSA makes the manufacturing process to require lower temperature, less fuel, and less calcite. However, it requires aluminum oxide, Al2O3, which would be originated from bauxite and bauxite‐derived wastes, and sulfur, coming from calcium sulfate or elemental sulfur. An eco‐efficiency assessment of CSA cements, benchmarked against the conventional Portland cement, has been performed following the principles of ISO 14045 on eco‐efficiency for a total of 240 CSA clinker production scenarios. The eco‐efficiency indicator relates an environmental indicator with a product system value indicator, and it is calculated for each of the studied parameters: bauxite geographical origin, the fuel used for clinkering, the source of sulfur, and the composition of the clinker. Eco‐efficiency results show a strong dependence on the origin of bauxite, while other parameters, as the fuel used, its content in sulfur, or the supply of other raw materials, are of less importance. The most eco‐efficient solutions are those with certain closeness to bauxite sources. To achieve global solutions, that is, cement‐making based on CSA independently of the origin of the raw materials, the amount of bauxite needs to be minimized and CSA composition restricted.  相似文献   
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Immune dysregulation is a hallmark of patients infected by SARS-CoV2 and the balance between immune reactivity and tolerance is a key determinant of all stages of infection, including the excessive inflammatory state causing the acute respiratory distress syndrome. The kynurenine pathway (KP) of tryptophan (Trp) metabolism is activated by pro-inflammatory cytokines and drives mechanisms of immune tolerance. We examined the state of activation of the KP by measuring the Kyn:Trp ratio in the serum of healthy subjects (n = 239), and SARS-CoV2-negative (n = 305) and -positive patients (n = 89). Patients were recruited at the Emergency Room of St. Andrea Hospital (Rome, Italy). Kyn and Trp serum levels were assessed by HPLC/MS-MS. Compared to healthy controls, both SARS-CoV2-negative and -positive patients showed an increase in the Kyn:Trp ratio. The increase was larger in SARS-CoV2-positive patients, with a significant difference between SARS-CoV2-positive and -negative patients. In addition, the increase was more prominent in males, and positively correlated with age and severity of SARS-CoV2 infection, categorized as follows: 1 = no need for intensive care unit (ICU); 2 ≤ 3 weeks spent in ICU; 3 ≥ 3 weeks spent in ICU; and 4 = death. The highest Kyn:Trp values were found in SARS-CoV2-positive patients with severe lymphopenia. These findings suggest that the Kyn:Trp ratio reflects the level of inflammation associated with SARS-CoV2 infection, and, therefore, might represent a valuable biomarker for therapeutic intervention.  相似文献   
5.
Cytogenetic studies in birds are still scarce compared to other vertebrates. Woodcreepers (Dendrocolaptidae) are part of a highly specialized group within the Suboscines of the New World. They are forest birds exclusive to the Neotropical region and similar to woodpeckers, at a comparable evolutionary stage. This paper describes for the first time the karyotypes of the Olivaceous and the Narrow-billed Woodcreeper using conventional staining with Giemsa and silver nitrate staining of the nucleolar organizer regions (Ag-NORs). Metaphases were obtained by fibular bone marrow culture. The chromosome number of the Olivaceous Woodcreeper was 2n = 82 and of the Narrow-billed Woodcreeper, 2n = 82. Ag-NORs in the largest macrochromosome pair and evidence of a chromosome inversion are described herein for the first time for this group.  相似文献   
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The essential oils of Artemisia arborescens growing in Sardinia (Italy), collected during three plant growth stages, i.e., from the vegetative stage to post‐blooming time, were characterized. Moreover, the in vitro antiproliferative and antioxidant activities of the oil isolated from aerial parts collected in February were evaluated. The essential oils belonged to the β‐thujone/chamazulene chemotype, notably with the highest amount of chamazulene (ca. 52%) ever detected up to now in the genus Artemisia and, in general, in essential oils. Quantitative variations in the oil composition were observed as the plant passes from the vegetative to the blooming stage. The oil was tested for its potential tumor cell growth‐inhibitory effect on T98G, MDA‐MB 435S, A375, and HCT116 human cell lines, using the MTT (=3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐2H‐tetrazolium bromide) assay. The highest activity was observed on A375 and HCT116 cell lines, with IC50 values of 14 μg/ml. Moreover, the in vitro antioxidant and free radical‐scavenging assays revealed the oil to be an effective scavenger of the ABTS radical cation, with an activity comparable to that of Trolox®. These results support the use of A. arborescens oil for the treatment of inflamed skin conditions. Finally, the composition of the polar fraction of the A. arborescens aerial parts was also examined, and the main component detected was 5‐O‐caffeoylquinic acid, which was identified for the first time in this plant.  相似文献   
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Background

Ipilimumab can result in durable clinical responses among patients with advanced melanoma. However, no predictive marker of clinical activity has yet been identified. We provide preliminary data describing the correlation between immunological parameters and response/survival among patients with advanced melanoma who received ipilimumab 10 mg/kg in an expanded access programme.

Methods

Patients received ipilimumab 10 mg/kg every 3 weeks (Q3W) for four doses (induction) and Q12W from week 24 (W24) as maintenance therapy. Tumor assessments were conducted Q12W. Expression of inducible T cell costimulator (ICOS) on CD4+ and CD8+ T cells was assessed at baseline, W7, W12 and W24, and the ratio between absolute neutrophils (N) and lymphocytes (L) determined at baseline, W4, W7 and W10.

Results

Median overall survival among 27 patients was 9.6 months (95 % CI 3.2–16.1), with 3- and 4-year survival rates of 20.4 %. Five patients survived >4 years. Patients with an increase in the number of circulating ICOS+ T cells at W7 were more likely to experience disease control and have improved survival. An N/L ratio below the median at W7 and W10 was also associated with better survival compared with an N/L ratio above the median.

Conclusions

Ipilimumab can induce long-term survival benefits in heavily pretreated patients with metastatic melanoma. Changes in the number of circulating ICOS+ T cells or N/L ratio during ipilimumab treatment may represent early markers of response. However, given the limited sample size, further investigation is required.  相似文献   
8.
Since the emergence of West Nile virus (WNV) in North America in 1999, there have been several reports of WNV activity in Central and South American countries. To detect WNV in Brazil, we performed a serological survey of horses from different regions of Brazil using recombinant peptides from domain III of WNV. Positive samples were validated with the neutralisation test. Our results showed that of 79 ELISA-positive horses, nine expressed WNV-specific neutralising antibodies. Eight of the infected horses were from the state of Mato Grosso do Sul and one was from the state of Paraíba. Our results provide additional evidence for the emergence of WNV in Brazil and for its circulation in multiple regions of the country.  相似文献   
9.
The azoles are the class of medications most commonly used to fight infections caused by Candida sp. Typically, resistance can be attributed to mutations in ERG11 gene (CYP51) which encodes the cytochrome P450 14α-demethylase, the primary target for the activity of azoles. The objective of this study was to identify mutations in the coding region of theERG11 gene in clinical isolates of Candidaspecies known to be resistant to azoles. We identified three new synonymous mutations in the ERG11 gene in the isolates of Candida glabrata (C108G, C423T and A1581G) and two new nonsynonymous mutations in the isolates of Candida krusei - A497C (Y166S) and G1570A (G524R). The functional consequence of these nonsynonymous mutations was predicted using evolutionary conservation scores. The G524R mutation did not have effect on 14α-demethylase functionality, while the Y166S mutation was found to affect the enzyme. This observation suggests a possible link between the mutation and dose-dependent sensitivity to voriconazole in the clinical isolate of C. krusei. Although the presence of the Y166S in phenotype of reduced azole sensitivity observed in isolate C. kruseidemands investigation, it might contribute to the search of new therapeutic agents against resistant Candida isolates.  相似文献   
10.
The objectives of this experiment were to (i) determine the efficacy of essential oils of clove (CO) and Lippia alba (EOLA) to induce deep anaesthesia in juvenile specimens (49.0 ± 6.2 g body mass, 16.6 ± 0.8 cm; n = 8 per treatment) of meagre (Argyrosomus regius); and (ii) study the feasibility of these substances, together with 2‐phenoxyethanol (2‐PHE), as potential sedatives [low concentration: (i) EOLA: 12 mg L?1; (ii) CO: 1 mg L?1; and (iii) 2‐PHE: 33 mg·L ?1; n = 8 per treatment] for live fish transport of this species. All test were performed at a constant temperature (18°C). Thus, the main primary stress indicator (plasma cortisol) and secondary factors (plasma metabolites) were evaluated. In addition, growth hormone (GH) mRNA expression was also evaluated in the pituitary gland. The results indicated that EOLA is considered to be effective for deep anaesthesia when the concentration is close to 160 mg L?1, while CO produces the same effect when lower concentrations are added (40–50 mg L?1). Regarding sedative concentrations, a significant ~3‐fold increase in plasma cortisol levels was detected in the EOLA group when compared to control specimens. In addition, glucose levels were not reduced and significantly increased (~1.6‐fold) for 2‐PHE in relation to the control fish. None of the anaesthetics promoted a significant difference for GH expression with respect to the control group, but a significant ~2‐fold increase for 2‐PHE treatment with respect to the EOLA exposition was found in this gene expression. Results show that none of the anaesthetics analysed, at least in the ranges of concentrations used in this study (EOLA 12 mg L?1, CO 1 mg L?1, 2‐PHE 33 mg L?1), are recommended for live fish transport, as shown by the absence of inhibition on the stress parameters assessed.  相似文献   
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