Legionella-protozoa-nematode interactions in aquatic biofilms and influence of Mip on Caenorhabditis elegans colonization.

Legionella pneumophila, the causative agent of Legionnaires disease, is naturally found in aquatic habitats. The intracellular life cycle within protozoa pre-adapted the "accidental" human pathogen to also infect human professional phagocytes like alveolar macrophages. Previous studies employing the model organism Caenorhabditis elegans suggest that also nematodes might serve as a natural host for L. pneumophila. Here, we report for the first time from a natural co-habitation of L. pneumophila and environmental nematode species within biofilms of a warm water spring. In addition, we identified the protozoan species Oxytricha bifaria, Stylonychia mytilus, Ciliophrya sp. which have never been described as potential interaction partners of L. pneumophila before. Modeling and dissection of the Legionella-protozoa-nematode interaction revealed that C. elegans ruptures Legionella-infected amoebal cells and by this means incorporate the pathogen. Further infection studies revealed that the macrophage infectivity potentiator (Mip) protein of L. pneumophila, which is known to bind collagen IV during human lung infection, promotes the colonization of the intestinal tract of L4 larvae of C. elegans and negatively influences the life span of the worms. The Mip-negative L. pneumophila mutant exhibited a 32-fold reduced colonization rate of the nematodes after 48h when compared to the wild-type strain. Taken together, these studies suggest that nematodes may serve as natural hosts for L. pneumophila, promote their persistence and dissemination in the environment, and co-evolutionarily pre-adapt the pathogen for interactions with extracellular constituents of human lung tissue.

Anisotropy effect of three-membered rings in (1)H NMR spectra: quantification by TSNMRS and assignment of the stereochemistry.

The spatial magnetic properties (through space NMR shieldings, TSNMRSs) of cyclopropane; of the heteroanalogous oxirane, thiirane, and aziridine; and of various substituted mono-, dis-, and tris-cyclic analogues have been computed by the GIAO perturbation method employing the nucleus independent chemical shift (NICS) concept and visualized as iso-chemical-shielding surfaces (ICSSs) of various size and direction. The TSNMRS values, thus obtained, can be employed to visualize the anisotropy (ring current) effect of the cyclopropane ring moiety. This approach has been employed to qualify and quantify substituent influences and contributions of appropriate ring heteroatoms O, NH, and S on the anisotropy (ring current) effect of three-membered ring moieties, and to assign the stereochemistry of mono-, bis-, and tris-cyclic structures containing cyclopropane as a structural element. Characteristic examples are included.

Bombyx mori silk/titania/gold hybrid materials for photocatalytic water splitting: combining renewable raw materials with clean fuels.

The synthesis, structure, and photocatalytic water splitting performance of two new titania (TiO2)/gold(Au)/Bombyx mori silk hybrid materials are reported. All materials are monoliths with diameters of up to ca. 4.5 cm. The materials are macroscopically homogeneous and porous with surface areas between 170 and 210 m2/g. The diameter of the TiO2 nanoparticles (NPs) - mainly anatase with a minor fraction of brookite - and the Au NPs are on the order of 5 and 7-18 nm, respectively. Addition of poly(ethylene oxide) to the reaction mixture enables pore size tuning, thus providing access to different materials with different photocatalytic activities. Water splitting experiments using a sunlight simulator and a Xe lamp show that the new hybrid materials are effective water splitting catalysts and produce up to 30 mmol of hydrogen per 24 h. Overall the article demonstrates that the combination of a renewable and robust scaffold such as B. mori silk with a photoactive material provides a promising approach to new monolithic photocatalysts that can easily be recycled and show great potential for application in lightweight devices for green fuel production.

A Case of Beta-propeller Protein-associated Neurodegeneration due to a Heterozygous Deletion of WDR45.

BACKGROUND: Static encephalopathy of childhood with neurodegeneration in adulthood is a phenotypically distinctive, X-linked dominant subtype of neurodegeneration with brain iron accumulation (NBIA). WDR45 mutations were recently identified as causal. WDR45 encodes a beta-propeller scaffold protein with a putative role in autophagy, and the disease has been renamed beta-propeller protein-associated neurodegeneration (BPAN). CASE REPORT: Here we describe a female patient suffering from a classical BPAN phenotype due to a novel heterozygous deletion of WDR45. An initial gene panel and Sanger sequencing approach failed to uncover the molecular defect. Based on the typical clinical and neuroimaging phenotype, quantitative polymerase chain reaction of the WDR45 coding regions was undertaken, and this showed a reduction of the gene dosage by 50% compared with controls. DISCUSSION: An extended search for deletions should be performed in apparently WDR45-negative cases presenting with features of NBIA and should also be considered in young patients with predominant intellectual disabilities and hypertonia/parkinsonism/dystonia.

Rare Variants in Neurodegeneration Associated Genes Revealed by Targeted Panel Sequencing in a German ALS Cohort.

Amyotrophic lateral sclerosis (ALS) is a progressive fatal multisystemic neurodegenerative disorder caused by preferential degeneration of upper and lower motor neurons. To further delineate the genetic architecture of the disease, we used comprehensive panel sequencing in a cohort of 80 German ALS patients. The panel covered 39 confirmed ALS genes and candidate genes, as well as 238 genes associated with other entities of the neurodegenerative disease spectrum. In addition, we performed repeat length analysis for C9orf72. Our aim was to (1) identify potentially disease-causing variants, to (2) assess a proposed model of polygenic inheritance in ALS and to (3) connect ALS with other neurodegenerative entities. We identified 79 rare potentially pathogenic variants in 27 ALS associated genes in familial and sporadic cases. Five patients had pathogenic C9orf72 repeat expansions, a further four patients harbored intermediate length repeat expansions. Our findings demonstrate that a genetic background of the disease can actually be found in a large proportion of seemingly sporadic cases and that it is not limited to putative most frequently affected genes such as C9orf72 or SOD1. Assessing the polygenic nature of ALS, we identified 15 patients carrying at least two rare potentially pathogenic variants in ALS associated genes including pathogenic or intermediate C9orf72 repeat expansions. Multiple variants might influence severity or duration of disease or could account for intrafamilial phenotypic variability or reduced penetrance. However, we could not observe a correlation with age of onset in this study. We further detected potentially pathogenic variants in other neurodegeneration associated genes in 12 patients, supporting the hypothesis of common pathways in neurodegenerative diseases and linking ALS to other entities of the neurodegenerative spectrum. Most interestingly we found variants in GBE1 and SPG7 which might represent differential diagnoses. Based on our findings, we recommend two-staged genetic testing for ALS in Germany in patients with familial and sporadic ALS, comprising C9orf72 repeat analysis followed by comprehensive panel sequencing including differential diagnoses that impair motor neuron function to meet the complexity of ALS genetics.

Serum Levels of Progranulin Do Not Reflect Cerebrospinal Fluid Levels in Neurodegenerative Disease.

Altered progranulin levels play a major role in neurodegenerative diseases, like Alzheimer's dementia (AD), frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS), even in the absence of GRN mutations. Increasing progranulin levels could hereby provide a novel treatment strategy. However, knowledge on progranulin regulation in neurodegenerative diseases remains limited. We here demonstrate that cerebrospinal fluid progranulin levels do not correlate with its serum levels in AD, FTD and ALS, indicating a differential regulation of its central and peripheral levels in neurodegeneration. Blood progranulin levels thus do not reliably predict central nervous progranulin levels and their response to future progranulin-increasing therapeutics.

Clinical variability in ataxia-telangiectasia.

Ataxia-telangiectasia (A-T) is an autosomal recessive inherited disease characterized by progressive childhood-onset cerebellar ataxia, oculomotor apraxia, choreoathetosis and telangiectasias of the conjunctivae. Further symptoms may be immunodeficiency and frequent infections, and an increased risk of malignancy. As well as this classic manifestation, several other non-classic forms exist, including milder or incomplete A-T phenotypes caused by homozygous or compound heterozygous mutations in the ATM gene. Recently, ATM mutations have been found in 13 Canadian Mennonites with early-onset, isolated, predominantly cervical dystonia, in a French family with generalized dystonia and in an Indian family with dopa-responsive cervical dystonia. In this article, we will describe a Turkish family with three affected sibs. Their phenotypes range from pure cervical dystonia associated with hand tremor to truncal and more generalized dystonic postures. Exome sequencing has revealed the potentially pathogenic compound heterozygous variants p.V2716A and p.G301VfsX19 in the ATM gene. The variants segregated perfectly with the phenotypes within the family. Both mutations detected in ATM have been shown to be pathogenic, and the α-fetoprotein, a marker of ataxia telangiectasia, was found to be increased. This report supports recent literature showing that ATM mutations are not exclusively associated with A-T but may also cause a more, even intra-familial variable phenotype in particular in association with dystonia.

Dystonia with aphonia, slow horizontal saccades, epilepsy and photic myoclonus: a novel syndrome?

BACKGROUND: Dystonia with anarthria and/or aphonia is a rare syndromic association. Here we present two cases with slowly progressive, severe generalized dystonia and aphonia, slow horizontal saccades, epilepsy and photic myoclonus. METHODS: Detailed clinical data were collected over two decades in the female (index) patient and for nine years in her similarly affected son. Sanger sequencing followed by exome sequencing was performed. RESULTS: Both patients had leg onset generalized dystonia with gradual rostral spread including prominent facial and oro-mandibular involvement. The index patient was anarthric, her son aphonic. Both had saccadic slowing, more marked for the horizontal plane, and subclinical epileptic activity. The index patient also had photic myoclonus and a combined axonal and demyelinating neuropathy. Known genetic causes of similar syndromes were not identified. CONCLUSION: These cases with caudo-rostrally spreading generalized dystonia with prominent facial and oro-mandibular involvement, severe speech impairment, marked slowing of horizontal saccades, and photic myoclonus likely represent a novel entity.