SLITRK2 variants associated with neurodevelopmental disorders impair excitatory synaptic function and cognition in mice.

SLITRK2 is a single-pass transmembrane protein expressed at postsynaptic neurons that regulates neurite outgrowth and excitatory synapse maintenance. In the present study, we report on rare variants (one nonsense and six missense variants) in SLITRK2 on the X chromosome identified by exome sequencing in individuals with neurodevelopmental disorders. Functional studies showed that some variants displayed impaired membrane transport and impaired excitatory synapse-promoting effects.

De novo variants in MED12 cause X-linked syndromic neurodevelopmental disorders in 18 females.

Purpose: MED12 is a subunit of the Mediator multiprotein complex with a central role in RNA polymerase II transcription and regulation of cell growth, development, and differentiation. This might underlie the variable phenotypes in males carrying missense variants in MED12, including X-linked recessive Ohdo, Lujan, and FG syndromes.

Methods: By international matchmaking we assembled variant and clinical data on 18 females presenting with variable neurodevelopmental disorders (NDDs) and harboring de novo variants in MED12.

Magnetic Sedimentation Velocities and Equilibria in Dilute Aqueous Ferrofluids.

Dilute ferrofluids have important applications in the separation of materials via magnetic levitation. However, dilute ferrofluids pose an additional challenge compared to concentrated ones. Migration of the magnetic nanoparticles toward a magnet is not well counteracted by a buildup of an osmotic pressure gradient, and consequently, homogeneity of the fluid is gradually lost.

Colloidal Stability of Aqueous Ferrofluids at 10 T.

Magnetic density separation is an emerging recycling technology by which several different waste materials-from plastic products, electronics, or other-can be sorted in a single continuous processing step. Larger-scale installations will require ferrofluids that remain stable at several teslas, high magnetic fields at which colloidal stability was not investigated before. Here we optically monitor the concentration profile of iron oxide nanoparticles in aqueous ferrofluids at a field of 10 T and a gradient of 100 T/m.

High Yield of Pathogenic Germline Mutations Causative or Likely Causative of the Cancer Phenotype in Selected Children with Cancer.

In many children with cancer and characteristics suggestive of a genetic predisposition syndrome, the genetic cause is still unknown. We studied the yield of pathogenic mutations by applying whole-exome sequencing on a selected cohort of children with cancer. To identify mutations in known and novel cancer-predisposing genes, we performed trio-based whole-exome sequencing on germline DNA of 40 selected children and their parents.

Genetic mapping and QTL analysis of Botrytis resistance in .

is an economically important cut flower. In the production and transportation of gerbera with unavoidable periods of high relative humidity, grey mould occurs and results in losses in quality and quantity of flowers. Considering the limitations of chemical use in greenhouses and the impossibility to use these chemicals in auction or after sale, breeding for resistant gerbera cultivars is considered as the best practical approach.

A colloidal route to fabricate hierarchical sticky and non-sticky substrates.

We present a facile and inexpensive bottom-up colloidal route to prepare sticky superhydrophobic surfaces and non-sticky ones. Either spin coating to assemble silica microspheres into random multilayered arrays or irreversible adsorption of gold nanoparticles is used to manufacture substrates with a single length scale roughness. Hierarchical roughness with multiple length scales is achieved by decorating the silica spheres with gold nanoparticles.

Novel, highly selective gold nanoparticle patterning on surfaces using pure water.

We present a simple, novel procedure to selectively deposit gold nanoparticles using pure water. It enables patterning of nanoparticle monolayers with a remarkably high degree of selectivity on flat as well as microstructured oxide surfaces. We demonstrate that water molecules form a thin "capping" layer on exposed thiol molecules within the mercaptan self-assembled layer.

Dipole directed ring assembly of Ni-coated Au-nanorods.

We demonstrate the synthesis of novel core-shell nanoring superstructures consisting of non-dipolar Au nanorods coated with magnetic Ni shells. We show that the magnetic dipole induced self-assembly can be tuned by selective reduction of Ni on gold nanorods. Superstructures range from nanorings containing physically separated particles to solid rigid nanorings.

Superhydrophobic surfaces by anomalous fluoroalkylsilane self-assembly on silica nanosphere arrays.

We present the self-assembled formation of nanosized PFDTS (1H,1H,2H,2H-perfluorodecyltrichlorosilane) features on multilayered silica sphere arrays. We reveal the importance of residual water within the microsphere multilayers during PFDTS deposition and discuss a possible mechanism for the formation of the siloxane nanostructures. The multiscaled roughness induced by these superstructures is shown to lead to superhydrophobic behavior.

Controlling the morphology of multi-branched gold nanoparticles.

We demonstrate a simple and versatile way to achieve high yield synthesis of shape- and size-controlled multi-branched gold nanoparticles (MBNPs). Control over the shape of the MBNPs was achieved by varying the ratio of gold to the mild reducing agent ascorbic acid, using a seed-mediated growth approach. Higher ascorbate concentrations resulted in the smoothing of branches, leading to the yield of relatively more isotropic particles.

Quantitative analysis of gold nanorod alignment after electric field-assisted deposition.

We have studied the alignment of colloidal gold nanorods, deposited from solution onto well-defined substrates in the presence of an AC electric field generated by micrometer spaced electrodes. The field strengths employed in our experiments are sufficiently large to overcome Brownian motion and induce accumulation and alignment of the nanorods in the region near the electrodes with their long axis parallel to the field. However, despite the large fields, we find that the degree of alignment is considerably smaller than what was previously reported for field-induced nanorod alignment in suspension.

Split hand/foot malformation due to chromosome 7q aberrations(SHFM1): additional support for functional haploinsufficiency as the causative mechanism.

We report on three patients with split hand/foot malformation type 1 (SHFM1). We detected a deletion in two patients and an inversion in the third, all involving chromosome 7q21q22. We performed conventional chromosomal analysis, array comparative genomic hybridization and fluorescence in situ hybridization.

Nine patients with a microdeletion 15q11.2 between breakpoints 1 and 2 of the Prader-Willi critical region, possibly associated with behavioural disturbances.

Behavioural differences have been described in patients with type I deletions (between breakpoints 1 and 3 (BP1-BP3)) or type II deletions (between breakpoints 2 and 3) of the 15q11.2 Prader-Willi/Angelman region. The larger type I deletions appear to coincide with more severe behavioural problems (autism, ADHD, obsessive-compulsive disorder).

A unique 970kb microdeletion in 9q33.3, including the NR5A1 gene in a 46,XY female.

We report on a female patient with XY sex reversal with clitoromegaly, neonatal male testosterone and AMH levels, and a normal urine steroid profile. Array CGH revealed a de novo microdeletion of chromosome 9q33.3, including the NR5A1 gene.

Long-term surveillance of invasive group A streptococcal disease in The Netherlands, 1994-2003.

A nationwide laboratory-based surveillance study of invasive group A streptococcal (GAS) infections was conducted in The Netherlands from May 1994 until December 2003 (average population during this period was 15 729 704). Microbiologically invasive isolates were obtained from 1504 patients, with most (70%) isolates cultured from blood. There was a clear seasonal pattern in invasive streptococcal infections, with an estimated annual incidence that peaked in 1996 (4.

Epidemiological features of invasive and noninvasive group A streptococcal disease in the Netherlands, 1992-1996.

A prospective, nationwide, laboratory-based surveillance of invasive group A streptococcal infections was conducted in the Netherlands from 1992 through 1996. Clinical and demographic data were obtained and all isolates were T/M typed. All noninvasive group A streptococcal isolates were registered from 1994 through 1996.

Typing of Aeromonas strains from patients with diarrhoea and from drinking water.

Aeromonas strains (187) from human diarrhoeal stools and from drinking water (263) in The Netherlands were typed by three different methods. Biotyping alone was found to be of little value for epidemiological studies because 84% of all strains belonged to only 10 biotypes. Common biotypes could be further differentiated by serotyping.

Identification of Klebsiella pneumoniae by DNA hybridization and fatty acid analysis.

On the basis of the idea that DNA sequences encoding cell surface-exposed regions of outer membrane proteins are genus or species specific, two oligonucleotide probes which were based on the PhoE protein of Klebsiella pneumoniae were evaluated. In slot blot hybridizations and in polymerase chain reactions, no cross-hybridizations were observed with non-Klebsiella strains. When the probes were tested on 75 different K-antigen reference Klebsiella strains, 16 strains were not recognized although they did produce PhoE protein under phosphate starvation.