Brain imaging of the cortex in ADHD: a coordinated analysis of large-scale clinical and population-based samples

Objective: Neuroimaging studies show structural alterations of various brain regions in children and adults with attention deficit hyperactivity disorder (ADHD), although nonreplications are frequent. The authors sought to identify cortical characteristics related to ADHD using large-scale studies. Methods: Cortical thickness and surface area (based on the Desikan–Killiany atlas) were compared between case subjects with ADHD (N=2,246) and control subjects (N=1,934) for children, adolescents, and adults separately in ENIGMA-ADHD, a consortium of 36 centers. To assess familial effects on cortical measures, case subjects, unaffected siblings, and control subjects in the NeuroIMAGE study (N=506) were compared. Associations of the attention scale from the Child Behavior Checklist with cortical measures were determined in a pediatric population sample (Generation-R, N=2,707). Results: In the ENIGMA-ADHD sample, lower surface area values were found in children with ADHD, mainly in frontal, cingulate, and temporal regions; the largest significant effect was for total surface area (Cohen’s d=−0.21). Fusiform gyrus and temporal pole cortical thickness was also lower in children with ADHD. Neither surface area nor thickness differences were found in the adolescent or adult groups. Familial effects were seen for surface area in several regions. In an overlapping set of regions, surface area, but not thickness, was associated with attention problems in the Generation-R sample. Conclusions: Subtle differences in cortical surface area are widespread in children but not adolescents and adults with ADHD, confirming involvement of the frontal cortex and highlighting regions deserving further attention. Notably, the alterations behave like endophenotypes in families and are linked to ADHD symptoms in the population, extending evidence that ADHD behaves as a continuous trait in the population. Future longitudinal studies should clarify individual lifespan trajectories that lead to nonsignificant findings in adolescent and adult groups despite the presence of an ADHD diagnosis

Subcortical brain volume, regional cortical thickness, and cortical surface area across disorders: findings from the ENIGMA ADHD, ASD, and OCD Working Groups

Objective Attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), and obsessive-compulsive disorder (OCD) are common neurodevelopmental disorders that frequently co-occur. We aimed to directly compare all three disorders. The ENIGMA consortium is ideally positioned to investigate structural brain alterations across these disorders. Methods Structural T1-weighted whole-brain MRI of controls (n=5,827) and patients with ADHD (n=2,271), ASD (n=1,777), and OCD (n=2,323) from 151 cohorts worldwide were analyzed using standardized processing protocols. We examined subcortical volume, cortical thickness and surface area differences within a mega-analytical framework, pooling measures extracted from each cohort. Analyses were performed separately for children, adolescents, and adults using linear mixed-effects models adjusting for age, sex and site (and ICV for subcortical and surface area measures). Results We found no shared alterations among all three disorders, while shared alterations between any two disorders did not survive multiple comparisons correction. Children with ADHD compared to those with OCD had smaller hippocampal volumes, possibly influenced by IQ. Children and adolescents with ADHD also had smaller ICV than controls and those with OCD or ASD. Adults with ASD showed thicker frontal cortices compared to adult controls and other clinical groups. No OCD-specific alterations across different age-groups and surface area alterations among all disorders in childhood and adulthood were observed. Conclusion Our findings suggest robust but subtle alterations across different age-groups among ADHD, ASD, and OCD. ADHD-specific ICV and hippocampal alterations in children and adolescents, and ASD-specific cortical thickness alterations in the frontal cortex in adults support previous work emphasizing neurodevelopmental alterations in these disorders

Establishing a Novel Genus-specific PCR for Mycobacteria with Identification to the Species Level by Restriction Endonucleases Using the16S-23S rDNA Spacer

In dieser Arbeit wurde eine genusspezifische PCR für Mykobakterien entwickelt und zusätzlich eine einfache Identifikation durch Restriktions Fragment Längen Polymorphismus (RFLP) bis zum Spezieslevel erreicht anhand des 16S – 23S rDNA Spacers. Es ist gelungen, mit der Auswahl der Primer, die Gattung Mykobakterien nach PCR und damit vor Restriktion , sicher von anderen nicht mykobakteriellen Spezies abzugrenzen und damit eine Genusspezifität zu erlangen. Es wurden insgesamt 811 Bakterienstämme untersucht, davon 678 mykobakterielle Stämme. Alle mykobakteriellen Stämme wurden von den neuen Primern amplifiziert. Von den nicht mykobakteriellen isolaten wurde nur Gordona terrae amplifiziert. Das ausgedachte RFLP Schema beinhaltet PCR Produkte in unterschiedlichen Größen swie die Restriktionsanalyse durch HaeIII und CfoI ( Endonukleasen). Es brachte 58 HaeIII Muster hervor, davon waren 49 ( 84%) einzigartig auf Speziesebene. Daher war der HaeIII Verdau zusammen mit den CfoI Ergebnissen ausrichend für eine korrekte Indentifizierung von 39 von 54 mykobakteriellen Taxone. Ein klar angelegter Algrhitmus veranschaulichte, dass sich die nachgebliebenen nicht identifizierten Spezies in fünf Cluster von nahe verwandten Spezies aufteilten. Diese wurden erfolgreich durch weitere Enzyme (TaqI, MspI, DdeI oder AvaII) separiert. Neben den langsamwachsenden Mykobakterien wurden so auch alle untersuchten schnellwachsenden Mykobakterien ( z.B. M. abcessus, M. chelonae, M. farcinogenes, M. fortuitum, M. peregrinum, und M. senegalense/sehr hohe 16S rDNA Sequenzsimilarität) korrekt identifieziert. Durch die hohe Intraspezies Sequenzstabilität und durch die Tatsache, dass die einzelnen Muster gut voneinander zu unterscheiden sind, eignet sich diese Methodefür schnelle und kosteneffektive Identifikation eines weiten Spektrums an Spezies ohne sequenzieren zu müssen. Aus phylogenetischem Gesichtspunkt, stimmen die Spacersequenzdaten gut mit den 16S rDNA Ergebnissen überein. Das wurde auch durch die Stämme mit nicht klassifizierter Taxonomie gezeigt. Da die Methode dieser Arbeit sowohl signifikante subspezifische Genotypen als auch ein weites Spektrum an mykobakteriellen Spezies durch die Identifikation von einem spezifischen Muster innerhalb einer Spezies erkannte, eignet sie sich nicht nur für Forschungszwecke, sondern kann auch in Routinelaboratorien angewandt werden.A novel genus-specific PCR for mycobacteria with simple identification to the species level by restriction fragment length polymorphism was established using the 16S-23S – rDNA spacer as a target. Panspecifity of primers was demonstrated on the genus level by testing 811 bacterial strains, of which were 678 mycobacterial strains. All mycobacterial isolates were amplified by the new primers. Among the nonmycobacterial isolates, only gordona terrae was amplified by the new primers. The RFLP sheme devised involves etimation of variable PCR product sizes together with HaeIII and CfoI restriction analysis. It yielded 58 HaeIII patterns, of which 49 (84%) were unique to the species level. Hence, HaeIII digestion together with CfoI results was sufficient for correct identification of 39 of 54 mycobacterial taxons. Following a clearly laid ot diagnostic algrithm, the remaining unidentified organisms fell into 5 clusters of closely related species, that were sucessfully separated using additional enzymes ( TaqI, MspI, DdeI or AvaII). Thus, next to slowly growing mycobacteria, all rapidly growing species studied, including M. abcessus, M. chelonae, M. farcinogenes, M. fortuitum, M. peregrinum, and M. senegalense ( with a very high 16S rDNA sequence similarity) were correctly identified. A high intraspecies sequence stability and the good dicriminative power of patterns indicate that this method is very suitable for rapid and cost- effective identification of a wide variety of mycobacterial species without the need for sequencing. Phylogenetically, spacer sequence data stand in good agreement with 16S rDNA sequencing results, as was shown by including strains with unsettled taxonomy. Sinc this approach recognized significant subspecific genotypes while identification of a broad spectrum of mycobacteria rested on identification of one specific RFLP pattern within a species, this method can be used by both reference (or research) and routine laboratories

Traumatic brain injury in the presence of Aβ pathology affects neuronal survival, glial activation and autophagy

Traumatic brain injury (TBI) presents a widespread health problem in the elderly population. In addition to the acute injury, epidemiological studies have observed an increased probability and earlier onset of dementias in the elderly following TBI. However, the underlying mechanisms of the connection between TBI and Alzheimer’s disease in the aged brain and potential exacerbating factors is still evolving. The aim of this study was to investigate cellular injury-induced processes in the presence of amyloid β (Aβ) pathology. For this purpose, a co-culture system of cortical stem-cell derived astrocytes, neurons and oligodendrocytes were exposed to Aβ42 protofibrils prior to a mechanically induced scratch injury. Cellular responses, including neurodegeneration, glial activation and autophagy was assessed by immunoblotting, immunocytochemistry, ELISA and transmission electron microscopy. Our results demonstrate that the combined burden of Aβ exposure and experimental TBI causes a decline in the number of neurons, the differential expression of the key astrocytic markers glial fibrillary acidic protein and S100 calcium-binding protein beta, mitochondrial alterations and prevents the upregulation of autophagy. Our study provides valuable information about the impact of TBI sustained in the presence of Aβ deposits and helps to advance the understanding of geriatric TBI on the cellular level

In-situ monitoring of the material composition in PBF-LB via optical emission spectroscopy

Powder bed fusion using a laser beam of metals (PBF-LB/M) is a widely used additive manufacturing (AM) technique that enables the material-efficient fabrication of complex geometries in metallic parts. However, achieving high-quality parts with desired properties heavily depends on variances in the manufacturing process and powder composition, making quality control an indispensable aspect of almost all applications. Today, mainly grayscale imaging or pyrometry are employed, whereas in situ recording of chemical (compositional) information has rarely been done during LBF-LB/M. This pilot study explores the feasibility of in-situ optical emission spectroscopy (OES) for elemental analysis of metallic samples during PBF-LB, at the example of Nd-Fe-B. Our findings suggest that the local emissivity of Fe and Nd lines can serve as a reliable indicator to determine the temperature and elemental concentration in the plasma. The results showed that Online-OES during PBF-LB enables tracking of how Nd content in as-build parts critically depends on the laser parameter used while printing the part

MEK inhibitors enhance therapeutic response towards ATRA in NF1 associated malignant peripheral nerve sheath tumors (MPNST) in-vitro.

Neurofibromatosis type 1 (NF1) is a hereditary tumor syndrome characterized by an increased risk of malignant peripheral nerve sheath tumors (MPNST). Chemotherapy of MPNST is still insufficient. In this study, we investigated whether human tumor Schwann cells derived from NF1 associated MPNST respond to all-trans retinoic acid (ATRA). We analyzed effects of ATRA and MEK inhibitor (MEKi) combination therapy.MPNST cell lines S462, T265, NSF1 were treated with ATRA and MEKi U0126 and PD0325901. We assessed cell viability, proliferation, migration, apoptosis and differentiation as well as mRNA expression of RAR and RXR subtypes and ATRA target genes such as CRABP2, CYP26A1, RARB and PDK1. We also analyzed CRABP2 methylation in cell lines and performed immunohistochemistry of human MPNST specimens.ATRA therapy reduced viability and proliferation in S462 and T265 cells, accompanied by differentiation, apoptosis and reduced migration. NSF1 cells which lacked RXRG expression did not respond to ATRA. We furthermore demonstrated that ATRA signaling was functional for common targets, and that mRNA expression of CRABP2 and its targets was raised by ATRA therapy, whereas alternative pathways via FABP5 were not induced. Finally, combination of ATRA and MEKi demonstrated additively reduced viability of T265 and S462 cells.We observed therapeutic effects in two of three MPNST cell lines pronounced by combination therapy. These data point to a potentially successful treatment of MPNST by combined application of ATRA and MEK inhibitors such as U0126 or PD0325901

In situ speciation and spatial mapping of Zn products during pulsed laser ablation in liquids (PLAL) by combined synchrotron methods

Pulsed laser ablation in liquids is a hierarchical multi-step process to produce pure inorganic nanoparticle colloids. Controlling this process is hampered by the partial understanding of individual steps and structure formation. In situ X-ray methods are employed to resolve macroscopic dynamics of nanosecond PLAL as well to analyse the distribution and speciation of ablated species with a microsecond time resolution. High time resolution can be achieved by synchrotron-based methods that are capable of ‘single-shot’ acquisition. X-ray multicontrast imaging by a Shack–Hartmann setup (XHI) and small angle X-ray scattering (SAXS) resolve evolving nanoparticles inside the transient cavitation bubble, while X-ray absorption spectroscopy in dispersive mode opens access to the total material yield and the chemical state of the ejecta. It is confirmed that during ablation nanoparticles are produced directly as well as reactive material is detected, which is identified in the early stage as Zn atoms. Nanoparticles within the cavitation bubble show a metal signature, which prevails for milliseconds, before gradual oxidation sets in. Ablation is described by a phase explosion of the target coexisting with full evaporation. Oxidation occurs only as a later step to already formed nanoparticles

Novel Diagnostic Algorithm for Identification of Mycobacteria Using Genus-Specific Amplification of the 16S-23S rRNA Gene Spacer and Restriction Endonucleases

A novel genus-specific PCR for mycobacteria with simple identification to the species level by restriction fragment length polymorphism (RFLP) was established using the 16S-23S ribosomal RNA gene (rDNA) spacer as a target. Panspecificity of primers was demonstrated on the genus level by testing 811 bacterial strains (122 species in 37 genera from 286 reference strains and 525 clinical isolates). All mycobacterial isolates (678 strains among 48 defined species and 5 indeterminate taxons) were amplified by the new primers. Among nonmycobacterial isolates, only Gordonia terrae was amplified. The RFLP scheme devised involves estimation of variable PCR product sizes together with HaeIII and CfoI restriction analysis. It yielded 58 HaeIII patterns, of which 49 (84%) were unique on the species level. Hence, HaeIII digestion together with CfoI results was sufficient for correct identification of 39 of 54 mycobacterial taxons and one of three or four of seven RFLP genotypes found in Mycobacterium intracellulare and Mycobacterium kansasii, respectively. Following a clearly laid out diagnostic algorithm, the remaining unidentified organisms fell into five clusters of closely related species (i.e., the Mycobacterium avium complex or Mycobacterium chelonae-Mycobacterium abscessus) that were successfully separated using additional enzymes (TaqI, MspI, DdeI, or AvaII). Thus, next to slowly growing mycobacteria, all rapidly growing species studied, including M. abscessus, M. chelonae, Mycobacterium farcinogenes, Mycobacterium fortuitum, Mycobacterium peregrinum, and Mycobacterium senegalense (with a very high 16S rDNA sequence similarity) were correctly identified. A high intraspecies sequence stability and the good discriminative power of patterns indicate that this method is very suitable for rapid and cost-effective identification of a wide variety of mycobacterial species without the need for sequencing. Phylogenetically, spacer sequence data stand in good agreement with 16S rDNA sequencing results, as was shown by including strains with unsettled taxonomy. Since this approach recognized significant subspecific genotypes while identification of a broad spectrum of mycobacteria rested on identification of one specific RFLP pattern within a species, this method can be used by both reference (or research) and routine laboratories