University of Düsseldorf

About: University of Düsseldorf is a education organization based out in Düsseldorf, Germany. It is known for research contribution in the topics: Population & Transplantation. The organization has 25225 authors who have published 49155 publications receiving 1946434 citations.

Imaging-based parcellations of the human brain

Abstract: A defining aspect of brain organization is its spatial heterogeneity, which gives rise to multiple topographies at different scales. Brain parcellation - defining distinct partitions in the brain, be they areas or networks that comprise multiple discontinuous but closely interacting regions - is thus fundamental for understanding brain organization and function. The past decade has seen an explosion of in vivo MRI-based approaches to identify and parcellate the brain on the basis of a wealth of different features, ranging from local properties of brain tissue to long-range connectivity patterns, in addition to structural and functional markers. Given the high diversity of these various approaches, assessing the convergence and divergence among these ensuing maps is a challenge. Inter-individual variability adds to this challenge but also provides new opportunities when coupled with cross-species and developmental parcellation studies.

RPK2 is an essential receptor-like kinase that transmits the CLV3 signal in Arabidopsis

Abstract: The shoot apical meristem (SAM) is the fundamental structure that is located at the growing tip and gives rise to all aerial parts of plant tissues and organs, such as leaves, stems and flowers. In Arabidopsis thaliana, the CLAVATA3 (CLV3) pathway regulates the stem cell pool in the SAM, in which a small peptide ligand derived from CLV3 is perceived by two major receptor complexes, CLV1 and CLV2-CORYNE (CRN)/SUPPRESSOR OF LLP1 2 (SOL2), to restrict WUSCHEL (WUS) expression. In this study, we used the functional, synthetic CLV3 peptide (MCLV3) to isolate CLV3-insensitive mutants and revealed that a receptor-like kinase, RECEPTOR-LIKE PROTEIN KINASE 2 (RPK2), also known as TOADSTOOL 2 (TOAD2), is another key regulator of meristem maintenance. Mutations in the RPK2 gene result in stem cell expansion and increased number of floral organs, as seen in the other clv mutants. These phenotypes are additive with both clv1 and clv2 mutations. Moreover, our biochemical analyses using Nicotiana benthamiana revealed that RPK2 forms homo-oligomers but does not associate with CLV1 or CLV2. These genetic and biochemical findings suggest that three major receptor complexes, RPK2 homomers, CLV1 homomers and CLV2-CRN/SOL2 heteromers, are likely to mediate three signalling pathways, mainly in parallel but with potential crosstalk, to regulate the SAM homeostasis.

Dipeptidyl peptidase‐4 (DPP‐4) inhibitors for type 2 diabetes mellitus

Abstract: Background In type 2 diabetes mellitus there is a progressive loss of beta-cell function. One new approach yielding promising results is the use of the orally active dipeptidyl peptidase-4 (DPP-4) inhibitors like sitagliptin and vildagliptin. Objectives To assess the effects of dipeptidyl peptidase-4 (DPP-4) inhibitors for type 2 diabetes mellitus. Search methods Studies were obtained from computerised searches of MEDLINE, EMBASE and The Cochrane Library. Selection criteria Studies were included if they were randomised controlled trials in adult people with type 2 diabetes mellitus and had a trial duration of at least 12 weeks. Data collection and analysis Two authors independently assessed risk of bias and extracted data. Pooling of studies was performed by means of fixed-effect meta-analysis. Main results Twenty-five studies of good quality were identified, 11 trials evaluated sitagliptin and 14 trials vildagliptin treatment. Altogether, 6743 patients were randomised in sitagliptin and 6121 patients in vildagliptin studies, respectively. Sitagliptin and vildagliptin studies ranged from 12 to 52 weeks duration. No data were published on mortality, diabetic complications, costs of treatment and health-related quality of life. Sitagliptin and vildagliptin therapy in comparison with placebo resulted in an HbA1c reduction of approximately 0.7% and 0.6%, respectively. Data on comparisons with active comparators were limited but indicated no improved metabolic control following DPP-4 intervention in contrast to other hypoglycaemic agents. Sitagliptin and vildagliptin therapy did not result in weight gain but weight loss was more pronounced following placebo interventions. No definite conclusions could be drawn from published data on sitagliptin and vildagliptin effects on measurements of beta-cell function. Overall, sitagliptin and vildagliptin were well tolerated, no severe hypoglycaemia was reported in patients taking sitagliptin or vildagliptin. All-cause infections increased significantly after sitagliptin treatment but did not reach statistical significance following vildagliptin therapy. All published randomised controlled trials of at least 12 weeks treatment with sitagliptin and vildagliptin only reported routine laboratory safety measurements Authors' conclusions DPP-4 inhibitors have some theoretical advantages over existing therapies with oral antidiabetic compounds but should currently be restricted to individual patients. Long-term data especially on cardiovascular outcomes and safety are urgently needed before widespread use of these new agents. More information on the benefit-risk ratio of DPP-4 inhibitor treatment is necessary especially analysing adverse effects on parameters of immune function. Also, long-term data are needed investigating patient-oriented parameters like health-related quality of life, diabetic complications and all-cause mortality.