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151.
The provision of healthcare in rural African communities is a highly complex and largely unsolved problem. Two main difficulties are the identification of individuals that are most likely affected by disease and the prediction of responses to health interventions. Social networks have been shown to capture health outcomes in a variety of contexts. Yet, it is an open question as to what extent social network analysis can identify and distinguish among households that are most likely to report poor health and those most likely to respond to positive behavioural influences. We use data from seven highly remote, post-conflict villages in Liberia and compare two prominent network measures: in-degree and betweenness. We define in-degree as the frequency in which members from one household are named by another household as a friends. Betweenness is defined as the proportion of shortest friendship paths between any two households in a network that traverses a particular household. We find that in-degree explains the number of ill family members, whereas betweenness explains engagement in preventative health. In-degree and betweenness independently explained self-reported health and behaviour, respectively. Further, we find that betweenness predicts susceptibility to, instead of influence over, good health behaviours. The results suggest that targeting households based on network measures rather than health status may be effective for promoting the uptake of health interventions in rural poor villages. 相似文献
152.
Zoonotic infections caused by several orthopoxviruses (OPV) like monkeypox virus or vaccinia virus have a significant impact on human health. In Europe, the number of diagnosed infections with cowpox viruses (CPXV) is increasing in animals as well as in humans. CPXV used to be enzootic in cattle; however, such infections were not being diagnosed over the last decades. Instead, individual cases of cowpox are being found in cats or exotic zoo animals that transmit the infection to humans. Both animals and humans reveal local exanthema on arms and legs or on the face. Although cowpox is generally regarded as a self-limiting disease, immunosuppressed patients can develop a lethal systemic disease resembling smallpox. To date, only limited information on the complex and, compared to other OPV, sparsely conserved CPXV genomes is available. Since CPXV displays the widest host range of all OPV known, it seems important to comprehend the genetic repertoire of CPXV which in turn may help elucidate specific mechanisms of CPXV pathogenesis and origin. Therefore, 22 genomes of independent CPXV strains from clinical cases, involving ten humans, four rats, two cats, two jaguarundis, one beaver, one elephant, one marah and one mongoose, were sequenced by using massive parallel pyrosequencing. The extensive phylogenetic analysis showed that the CPXV strains sequenced clearly cluster into several distinct clades, some of which are closely related to Vaccinia viruses while others represent different clades in a CPXV cluster. Particularly one CPXV clade is more closely related to Camelpox virus, Taterapox virus and Variola virus than to any other known OPV. These results support and extend recent data from other groups who postulate that CPXV does not form a monophyletic clade and should be divided into multiple lineages. 相似文献
153.
The reaction of halflanthanidocene aryloxides CpR′Ln(OArtBu,R)2 (Ln = Y, La, Lu; CpR′ = C5Me5, C4Me4H; R = H, Me) and halflanthanidocene alkoxides [(C5Me5)Ln(OCH2CMe3)2]2 (Ln = Y, Lu) with trimethylaluminum (TMA) was investigated. Monomeric CpR′Ln(OArtBu,R)2, derived from the ortho-tBu-substituted OC6H2tBu2-2,6-R-4 (R = H, Me) ligands, form mono(tetramethylaluminate) complexes CpR′Ln(OArtBu,R)(AlMe4) for the smaller lanthanide metal centers yttrium and lutetium. Such an [aryloxide] → [aluminate] ligand exchange was not observed at the larger lanthanum metal center. The mobility of the tetramethylaluminate ligands of complexes CpR′Ln(OArtBu,R)(AlMe4) (Ln = Y, Lu) was examined by variable-temperature (VT) 1H NMR spectroscopy, revealing two signals for bridging and terminal methyl groups at lower temperatures. The treatment of complexes CpR′Ln(OArtBu,R)(AlMe4) with donor solvent d8-THF gave CpR′Ln(OArtBu,R)(Me)(d8-THF)2 (Ln = Y, Lu) with terminal methyl groups, according to a donor-induced aluminate cleavage reaction. Dimeric [(C5Me5)Ln(OCH2CMe3)2]2 (Ln = Y, Lu) was synthesized from (C5Me5)Ln(NiPr2)2(THF) and reacted with two equivalents of TMA per Ln center to yield monomeric bis(TMA) adduct complexes (C5Me5)Ln(OCH2CMe3)2(AlMe3)2(Ln = Y, Lu). VT NMR spectroscopic studies confirmed a high mobility of the Ln(μ-OCH2CMe3)(μ-Me)AlMe2 moieties at an ambient temperature. Both bis(TMA) adduct complexes were characterized by X-ray structure analysis. 相似文献
154.
Hilkea Mutschall Sophie Winkler Volker Weisbach Andreas Arkudas Raymund E. Horch Dominik Steiner 《Journal of cellular and molecular medicine》2020,24(12):7034-7043
The microvascular endothelial network is essential for bone formation and regeneration. In this context, endothelial cells not only support vascularization but also influence bone physiology via cell contact‐dependent mechanisms. In order to improve vascularization and osteogenesis in tissue engineering applications, several strategies have been developed. One promising approach is the coapplication of endothelial and adipose derived stem cells (ADSCs). In this study, we aimed at investigating the best ratio of human umbilical vein endothelial cells (HUVECs) and osteogenic differentiated ADSCs with regard to proliferation, apoptosis, osteogenesis and angiogenesis. For this purpose, cocultures of ADSCs and HUVECs with ratios of 25%:75%, 50%:50% and 75%:25% were performed. We were able to prove that cocultivation supports proliferation whereas apoptosis was unidirectional decreased in cocultured HUVECs mediated by a p‐BAD‐dependent mechanism. Moreover, coculturing ADSCs and HUVECs stimulated matrix mineralization and the activity of alkaline phosphatase (ALP). Increased gene expression of the proangiogenic markers eNOS, Flt, Ang2 and MMP3 as well as sprouting phenomena in matrigel assays proved the angiogenic potential of the coculture. In summary, coculturing ADSCs and HUVECs stimulates proliferation, cell survival, osteogenesis and angiogenesis particularly in the 50%:50% coculture. 相似文献
155.
Andreas B. Herrmann Martha-Lena Müller Martin F. Orth Jörg P. Müller Alma Zernecke Andreas Hochhaus Thomas Ernst Elke Butt Jochen J. Frietsch 《Journal of cellular and molecular medicine》2020,24(5):2942-2955
Chronic myeloid leukaemia (CML) is a clonal myeloproliferative stem cell disorder characterized by the constitutively active BCR-ABL tyrosine kinase. The LIM and SH3 domain protein 1 (LASP1) has recently been identified as a novel BCR-ABL substrate and is associated with proliferation, migration, tumorigenesis and chemoresistance in several cancers. Furthermore, LASP1 was shown to bind to the chemokine receptor 4 (CXCR4), thought to be involved in mechanisms of relapse. In order to identify potential LASP1-mediated pathways and related factors that may help to further eradicate minimal residual disease (MRD), the effect of LASP1 on processes involved in progression and maintenance of CML was investigated. The present data indicate that not only overexpression of CXCR4, but also knockout of LASP1 contributes to proliferation, reduced apoptosis and migration as well as increased adhesive potential of K562 CML cells. Furthermore, LASP1 depletion in K562 CML cells leads to decreased cytokine release and reduced NK cell-mediated cytotoxicity towards CML cells. Taken together, these results indicate that in CML, reduced levels of LASP1 alone and in combination with high CXCR4 expression may contribute to TKI resistance. 相似文献
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160.
Arun K. Bose Arthur Gessler Andreas Bolte Alessandra Bottero Allan Buras Maxime Cailleret J. Julio Camarero Matthias Haeni Ana‐Maria Here Andrea Hevia Mathieu Lvesque Juan C. Linares Jordi Martinez‐Vilalta Luis Matías Annette Menzel Raúl Snchez‐Salguero Matthias Saurer Michel Vennetier Daniel Ziche Andreas Rigling 《Global Change Biology》2020,26(8):4521-4537
Global climate change is expected to further raise the frequency and severity of extreme events, such as droughts. The effects of extreme droughts on trees are difficult to disentangle given the inherent complexity of drought events (frequency, severity, duration, and timing during the growing season). Besides, drought effects might be modulated by trees’ phenotypic variability, which is, in turn, affected by long‐term local selective pressures and management legacies. Here we investigated the magnitude and the temporal changes of tree‐level resilience (i.e., resistance, recovery, and resilience) to extreme droughts. Moreover, we assessed the tree‐, site‐, and drought‐related factors and their interactions driving the tree‐level resilience to extreme droughts. We used a tree‐ring network of the widely distributed Scots pine (Pinus sylvestris) along a 2,800 km latitudinal gradient from southern Spain to northern Germany. We found that the resilience to extreme drought decreased in mid‐elevation and low productivity sites from 1980–1999 to 2000–2011 likely due to more frequent and severe droughts in the later period. Our study showed that the impact of drought on tree‐level resilience was not dependent on its latitudinal location, but rather on the type of sites trees were growing at and on their growth performances (i.e., magnitude and variability of growth) during the predrought period. We found significant interactive effects between drought duration and tree growth prior to drought, suggesting that Scots pine trees with higher magnitude and variability of growth in the long term are more vulnerable to long and severe droughts. Moreover, our results indicate that Scots pine trees that experienced more frequent droughts over the long‐term were less resistant to extreme droughts. We, therefore, conclude that the physiological resilience to extreme droughts might be constrained by their growth prior to drought, and that more frequent and longer drought periods may overstrain their potential for acclimation. 相似文献