COMMUNICATION Download: 0| View: 1| Comments: 0 | doi:10.20944/preprints201906.0278.v1
Subject: Life Sciences, Biophysics Keywords: photosystem II; redox potential; electron transfer; charge separation; photo-inhibition
Online: 27 June 2019 (05:54:13 CEST)
Structural perturbations in the Mn4CaO5 cluster site, an oxygen-evolving complex of photosystem II, such as those induced by Ca2+/Sr2+ exchanges or Ca/Mn-removal have been known to induce long-range positive shifts (+30 mV to +150 mV) in the redox potential of the primary quinone electron acceptor plastoquinone A (QA) located 40 Å distant from the OEC. Here, we reanalyzed the crystal structure of Sr-PSII solved at 2.1 Å and compare it with the native Ca-PSII of 1.9 Å with focus on the acceptor site and report on the possible long-range interactions between the donor, Mn4Ca(Sr)O5 cluster, and acceptor sites.
ARTICLE Download: 0| View: 2| Comments: 0 | doi:10.20944/preprints201906.0277.v1
Subject: Life Sciences, Other Keywords: salutogenic cities; walkable environments; urban health; physical activity; healthy urban planning; Bayesian network; causal network
Online: 27 June 2019 (05:50:41 CEST)
Background: The World Health Organization (WHO) stresses the need to create active environments, able to promote physical activity of people, according to their ability. Objective; This paper describes a new tool curried out to meaasure the relationship between the characteristics of urban space and its salutogenicity, intended as its ability to address population toward healthy lifestyles. Salutogenity has been read in terms of ergonomics of urban space. Method: The tool includes a set of 67 parameters, classified in needs, requirements and performance. It focuses on three requirements: usability, wellbeing and safety. The related performances are measured by a set of 29 indicators, divided in 5 categories (natural elements, built environment, mobility, urban furniture and perceived environment). To calibrate the tool, it was applied to 10 neighborhoods of Rieti city. To take into account the relationship between the variables, a causal network (Bayesian network) was applied. Findings: The average value of ergonomics of Rieti city, obtained applying the discrete bayesian model is 44.25%. Using the network, it is evident that by intervening on one node, the information requested expands to all the other nodes to which it is connected directly or indirectly, showing all the possible related factors. Conclusions: By using the tool and the discrete bayesian network it was possible to focus on the realities requiring analysis and to indicate the areas where the first interventions would be useful to increase the value of the analyzed nodes and, consequently, to improve the urban salutogenicity.
ARTICLE Download: 0| View: 6| Comments: 0 | doi:10.20944/preprints201906.0275.v1
Subject: Life Sciences, Molecular Biology Keywords: ketogenic diet; breast cancer; xenograft; untargeted metabolomics; HPLC-MS; reversed phase chromatography; hydrophilic interaction liquid chromatography
Online: 27 June 2019 (05:35:28 CEST)
Ketogenic diet (KD) is getting in the focus as auxiliary cancer therapy, since it provides sufficient energy supply for healthy cells, while impairing energy production in tumor cells underlying the Warburg effect. Thereby, it can assist in inhibiting tumor growth and simultaneously counteract cachexia, which is frequently observed in cancer patients under chemotherapy. In order to provide molecular evidence for the proposed synergistic inhibition of tumor growth, we applied untargeted quantitative metabolome analysis on a breast cancer xenograft mouse model. Healthy mice and such bearing breast cancer xenografts and receiving chemotherapy were compared after treatment with control diet and KD. Metabolomic profiling was performed on plasma samples, applying high-performance liquid chromatography coupled to tandem mass spectrometry. Statistical analysis revealed metabolic fingerprints comprising numerous significantly regulated features in the group of mice bearing breast cancer. This fingerprint disappeared after treatment with KD, resulting in recovery to the metabolic status observed in healthy mice receiving control diet. Moreover, amino acid metabolism as well as fatty acid transport were found to be affected by both, the tumor and the applied KD. Our results provide clear evidence of a significant molecular effect of KD in the context of tumor growth inhibition.