Intricate macrophage-colorectal cancer cell communication in response to radiation

Both cancer and tumour-associated host cells are exposed to ionizing radiation when a tumour is subjected to radiotherapy. Macrophages frequently constitute the most abundant tumour-associated immune population, playing a role in tumour progression and response to therapy. The present work aimed to evaluate the importance of macrophage-cancer cell communication in the cellular response to radiation. To address this question, we established monocultures and indirect co-cultures of human monocyte-derived macrophages with RKO or SW1463 colorectal cancer cells, which exhibit higher and lower radiation sensitivity, respectively. Mono- and co-cultures were then irradiated with 5 cumulative doses, in a similar fractionated scheme to that used during cancer patients' treatment (2 Gy/fraction/day). Our results demonstrated that macrophages sensitize RKO to radiation-induced apoptosis, while protecting SW1463 cells. Additionally, the co-culture with macrophages increased the mRNA expression of metabolism- and survival-related genes more in SW1463 than in RKO. The presence of macrophages also upregulated glucose transporter 1 expression in irradiated SW1463, but not in RKO cells. In addition, the influence of cancer cells on the expression of pro- and anti-inflammatory macrophage markers, upon radiation exposure, was also evaluated. In the presence of RKO or SW1463, irradiated macrophages exhibit higher levels of pro-inflammatory TNF, IL6, CCL2 and CCR7, and of anti-inflammatory CCL18. However, RKO cells induce an increase of macrophage pro-inflammatory IL1B, while SW1463 cells promote higher pro-inflammatory CXCL8 and CD80, and also anti-inflammatory VCAN and IL10 levels. Thus, our data demonstrated that macrophages and cancer cells mutually influence their response to radiation. Notably, conditioned medium from irradiated co-cultures increased non-irradiated RKO cell migration and invasion and did not impact on angiogenesis in a chicken embryo chorioallantoic membrane assay. Overall, the establishment of primary human macrophage-cancer cell co-cultures revealed an intricate cell communication in response to ionizing radiation, which should be considered when developing therapies adjuvant to radiotherapy

Expansion of heat-cured mortars

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Possible mechanisms of expansion of concrete exposed to elevated temperatures during curing (also known as DEF) and implications for avoidance of field problems

The phenomenon of expansion in concretes which have been exposed to elevated temperatures during curing and subsequently to moisture is discussed; in particular, the relationship of this expansion to the formation of ettringite after initial curing (delayed ettringite formation). Evidence is also presented for the possible implication of the C-S-H gel in the expansion process. The avoidance of this type of expansion in field concrete is also discussed. The data show that expansion occurs only when the concrete temperature during hydration exceeds 65°C and that the proportion of cements that expand under laboratory testing conditions increases as the temperature of exposure increases. Tests on limited numbers of cements have indicated that some factors in the cement that appear to influence the tendency of the concrete to expand after elevated temperature curing (such as, alkalis content, fineness, SO3), but there is no general relationship between these factors and the degree of expansion valid across the range of commercial cements. This means that the selection of a cement within certain limits will not guarantee the avoidance of expansion if the concrete is exposed to a high enough temperature during curing

What causes differences of C-S-H gel grey levels in backscattered electron images?

Backscattered electron (BSE) images of heat-cured concretes show alite grains surrounded by inner C-S-H gel of two distinct grey levels (referred to as two-tone inner C-S-H gel). The lighter rim forms at elevated temperature whereas the darker rim develops during subsequent exposure to moisture at 20 °C. This microstructural feature can potentially be used as an indicator to assess the curing history of a concrete. However, microstructural examinations of room-temperature concretes containing silica fume or which have been exposed to severe conditions (external sulfate, carbonation) also show distinct rims of two-tone inner C-S-H gel. The chemical compositions of the rims were determined by EDX microanalysis in the scanning electron microscope (SEM). Our results show that for heat-cured samples, the different grey levels of the two-tone inner C-S-H are caused by relative differences in microporosity and water content and not by ones in chemical composition. However, in silica-fume blended concrete, sulfate attacked or carbonated specimens the different grey levels of the two-tone inner C-S-H gel were associated with significant differences in chemical composition. This difference allows two-tone inner C-S-H gel arising from heat curing to be distinguished from that arising from these other causes. © 2002 Elsevier Science Ltd. All rights reserved

Delayed ettringite formation

Delayed ettringite formation (DEF) can damage concrete that has experienced a temperature above about 70°C. Claims that slow release of sulfate from the clinker can have a similar effect in concrete not thus heated are unsupported. Chemical and microstructural aspects of DEF are reviewed. Expansion results from formation of ettringite crystals of submicrometre size in the paste, the larger crystals readily observed in cracks and voids being recrystallisation products. The rate and ultimate extent of expansion are influenced by factors of three types: chemistry, which determines how much ettringite can be formed; paste microstructure, which determines the stresses produced by its formation; and concrete or mortar microstructure, which determines the response of the material to those stresses. Alkali present before the end of the heat treatment can increase expansion, but when present subsequently, it decreases expansion by inhibiting ettringite formation. Leaching therefore promotes expansion. © 2001 Elsevier Science Ltd

“Does the Apple Fall Far from the Tree?” The Role of Parental Factors in Filipino Adolescent Activism

It is widely believed that parents play a role in the outcome of their children. However, there is a scarcity in the literature tackling the parent-child relationship with regard to activist behaviors in offspring. To address this deficit, the study surveyed Senior High School students (N = 300) from the Integrated School of a private Metro Manila university to measure their involvement in social activism (adolescent activism) and to identify its relationship with parental factors (parental activism, parental support, parental psychological control) while accounting for sex and academic strand. The top three (3) forms of activism that the students engaged in were social media activism, voluntary work in educational activities, and e-volunteerism. Results indicate that females and their parents engage in social activism more than males and their parents. A significant difference in adolescent activism was found between the academic strands (F(2,297) = 3.15, p = .04), with HUMSS students scoring significantly higher than STEM students. After controlling for sex and strand, parental activism was found to be the most significant correlate of adolescent activism (R² = .37, F(4, 292) = 42.43, p = \u3c.001), followed by parental psychological control (R² = .4, F(5, 292) = 38.38, p = \u3c.001)