Pairing of Competitive and Topologically Distinct Regulatory Modules Enhances Patterned Gene Expression

Biological networks are inherently modular, yet little is known about how modules are assembled to enable coordinated and complex functions. We used RNAi and time series, whole-genome microarray analyses to systematically perturb and characterize components of a Caenorhabditis elegans lineage-specific transcriptional regulatory network. These data are supported by selected reporter gene analyses and comprehensive yeast one-hybrid and promoter sequence analyses. Based on these results, we define and characterize two modules composed of muscle- and epidermal-specifying transcription factors that function together within a single cell lineage to robustly specify multiple cell types. The expression of these two modules, although positively regulated by a common factor, is reliably segregated among daughter cells. Our analyses indicate that these modules repress each other, and we propose that this cross-inhibition coupled with their relative time of induction function to enhance the initial asymmetry in their expression patterns, thus leading to the observed invariant gene expression patterns and cell lineage. The coupling of asynchronous and topologically distinct modules may be a general principle of module assembly that functions to potentiate genetic switches.Molecular and Cellular Biolog

Clinical variety and prognosis of intracranial arachnoid cysts in children

Arachnoid cysts (AC) occur in different intracranial locations. Management and prognosis depend on the clinical presentation and treatment guidelines do not exist. With this study, we want to demonstrate the clinical variety of arachnoid cysts in children and place a focus on outcome factors in operated cases. This retrospective study of a consecutive single unit series of children, who underwent AC surgery between January 2010 and September 2019, provides demographic, clinical, imaging data, and information about surgical treatment and outcome. Overall, 63 patients (71.4 male) underwent surgery. Mean age was 50 months (0-191). Mean follow-up was 40 months (0-121). Eighty-one percent of patients presented with symptoms/signs of raised ICP. Focal neurological deficits were present in 15.9%, headache in 11.1% of children. Galassi cysts represented the predominant type (30.2%), followed by suprasellar (14.3%), quadrigeminal (12.7%), retrocerebellar, CPA and midline (each 11.1%), and hemispheric cysts (7.9%). Endoscopic and microsurgical fenestrations were performed in 27% and 58.7%, stent or shunt insertion in 6.3%/57.9% of the cases. In 33.3% of the cases one and in 12.7%, a second reintervention became necessary. Reoperation rate was significantly higher in children <1 year (p = 0.003). Cyst volume decreased in 85.7%. Seventy percent of the patients were symptom free, 5% suffered from headache, and 22% from developmental disorders. All focal neurological symptoms resolved. Complication rate and outcome are depending on age and cyst location. Recurrence and revision rates are significantly higher in young infants (p = 0.003). Midline cysts with CCA are associated with developmental disorders

Application of Indicator Systems for Monitoring and Assessment of Desertification from National to Global Scales

Current initiatives of the UNCCD on defining minimum sets of indicators for monitoring and impact assessment of the implementation of the Convention have acknowledged that an important missing element in this process is an approved methodology of defining affected areas, emphasizing the importance of a more uniform identification methodology. Rather than discussing fixed indicator sets, this paper suggests how the UNCCD community progressively can make use of a flexible framework of analytical approaches that have been recently developed by scientific research, allowing a standardized but flexible use of indicator sets adapted to specific objectives or desertification issues relevant for implementing the Convention. Science has made progress in understanding major issues and proximate causes of dryland degradation such that indicator sets can be accordingly selected from the wealth of existing and documented indicator systems. The selection and combination should be guided according to transparent criteria given by existing indicator frameworks adapted to desertification conceptual frameworks such as the Dryland Development Paradigm (DDP). The concept of desertification issues suggested by recent research could be a pragmatic entry level for selecting area- and theme-specific sets of indicators from existing databases. Working on different dryland sub-types through a meaningful stratification is proposed to delimit and characterize affected areas beyond national levels. Such stratification could be achieved by combining existing Land Use information with additional biophysical and socio-economic data sets. This would allow indicator based monitoring and assessment in a framework of specific dryland degradation issues and their impact on key ecosystem services.JRC.DDG.H.7-Land management and natural hazard

Application of indicator systems for monitoring and assessment of desertification from national to global scales

This paper suggests how the United Nations Convention to Combat Desertification (UNCCD) community can progressively make use of a flexible framework of analytical approaches that have been recently developed by scientific research. This allows a standardized but flexible use of indicator sets adapted to specific objectives or desertification issues relevant for implementing the Convention. Science has made progress in understanding major issues and proximate causes of dryland degradation such that indicator sets can be accordingly selected from the wealth of existing and documented indicator systems. The selection and combination should be guided according to transparent criteria given by existing indicator frameworks adapted to desertification conceptual frameworks such as the Dryland Development Paradigm and can act as a pragmatic entry point for selecting area- and theme-specific sets of indicators from existing databases. Working on different dryland sub-types through a meaningful stratification is proposed to delimit and characterize affected areas beyond the national level. Such stratification could be achieved by combining existing land use information with additional biophysical and socio-economic data sets, allowing indicator-based monitoring and assessment to be embedded in a framework of specific dryland degradation issues and their impacts on key ecosystem services