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Increased neurofilament light (NfL) protein in biofluids is reflective of neurodegeneration and has gained interest as a biomarker across neurodegenerative diseases. In spinocerebellar ataxia type 3 (SCA3), the most common dominantly inherited ataxia, patients exhibit progressive NfL increases in peripheral blood when becoming symptomatic, remaining stably elevated throughout further disease course. However, progressive NfL changes are not yet validated in relevant preclinical SCA3 animal models, hindering its application as a biomarker during therapeutic development. We used ultra-sensitive single-molecule array (Simoa) to measure blood NfL over disease progression in the YACQ84 mouse, assessing relationships with measures of disease severity including age, CAG repeat size, and magnetic resonance spectroscopy. We show that YACQ84 mice exhibit increased blood NfL, concomitant with ataxia-related motor deficits and correlated with neurometabolite abnormalities. Our findings establish natural history progression of NfL increases in the preclinical YACQ84 mouse, further supporting the utility of blood NfL as a peripheral neurodegeneration biomarker and informing coinciding timelines of different measures of SCA3 pathogenesis.Summary statementPeripheral blood of SCA3 YACQ84 mice exhibits increased abundance of neuronal-specific NfL protein directly associating with disease progression, providing an accessible disease biofluid biomarker to interrogate in preclinical therapeutic studies.

Spinocerebellar ataxia Type 3 (SCA3), the most common dominantly inherited ataxia, is a polyglutamine neurodegenerative disease for which there is no disease-modifying therapy. The polyglutamine-encoding CAG repeat expansion in theATXN3gene results in expression of a mutant form of the ATXN3 protein, a deubiquitinase that causes selective neurodegeneration despite being widely expressed. The mechanisms driving neurodegeneration in SCA3 are unclear. Research to date, however, has focused almost exclusively on neurons. Here, using equal male and female age-matched transgenic mice expressing full-length human mutantATXN3, we identified early and robust transcriptional changes in selectively vulnerable brain regions that implicate oligodendrocytes in disease pathogenesis. We mapped transcriptional changes across early, mid, and late stages of disease in two selectively vulnerable brain regions: the cerebellum and brainstem. The most significant disease-associated module through weighted gene coexpression network analysis revealed dysfunction in SCA3 oligodendrocyte maturation. These results reflect a toxic gain-of-function mechanism, asATXN3KO mice do not exhibit any impairments in oligodendrocyte maturation. Genetic crosses to reporter mice revealed a marked reduction in mature oligodendrocytes in SCA3-disease vulnerable brain regions, and ultrastructural microscopy confirmed abnormalities in axonal myelination. Further study of isolated oligodendrocyte precursor cells from SCA3 mice established that this impairment in oligodendrocyte maturation is a cell-autonomous process. We conclude that SCA3 is not simply a disease of neurons, and the search for therapeutic strategies and disease biomarkers will need to account for non-neuronal involvement in SCA3 pathogenesis.SIGNIFICANCE STATEMENTDespite advances in spinocerebellar ataxia Type 3 (SCA3) disease understanding, much remains unknown about how the disease gene causes brain dysfunction ultimately leading to cell death. We completed a longitudinal transcriptomic analysis of vulnerable brain regions in SCA3 mice to define the earliest and most robust changes across disease progression. Through gene network analyses followed up with biochemical and histologic studies in SCA3 mice, we provide evidence for severe dysfunction in oligodendrocyte maturation early in SCA3 pathogenesis. Our results advance understanding of SCA3 disease mechanisms, identify additional routes for therapeutic intervention, and may provide broader insight into polyglutamine diseases beyond SCA3.

Spinocerebellar ataxia type 3 (SCA3) is the most common dominantly inherited ataxia. Currently, no preventative or disease-modifying treatments exist for this progressive neurodegenerative disorder, although efforts using gene silencing approaches are under clinical trial investigation. The disease is caused by a CAG repeat expansion in the mutant gene, ATXN3, which produces an abnormally enlarged polyglutamine tract in the mutant ATXN3 protein. Similar to other paradigmatic neurodegenerative diseases, studies evaluating the pathogenic mechanism focus primarily on neuronal implications. Consequently, therapeutic interventions generated to target these deficiencies often overlook non-neuronal contributions to disease. Our lab recently reported that oligodendrocytes display some of the earliest and most progressive dysfunction in SCA3 mice. Evidence of disease-associated oligodendrocyte signatures has also been reported in other neurodegenerative diseases, including Alzheimer’s disease, ALS, Parkinson’s disease, and Huntington’s disease. Here, we assess the effects of anti-ATXN3 antisense oligonucleotide (ASO) treatment on oligodendrocyte dysfunction in both premanifest and symptomatic SCA3 mouse models. We report a severe, but modifiable, deficit in oligodendrocyte maturation caused by the toxic gain-of-function of mutant ATXN3 early in SCA3 disease progression that is transcriptionally, biochemically, and functionally rescued with anti-ATXN3 ASO. Our results establish the necessity of considering non-neuronal targets in future neurodegenerative disease therapies.

Germline DNA alterations affecting homologous recombination pathway genes have been associated with pancreatic cancer (PC) risk. BRCA2 is the most studied gene and affects the management of PC patients and their families. Even though recent reports have suggested a similar role of germline ATM pathogenic variants (PV) in familial PC, there is still a disagreement between experts on how it could affect patient management given the lack of proper PC risk estimates. We retrospectively analyzed the germline data of 257 PC patients among whom nearly 50% were sporadic cases. We showed similar frequencies of BRCA2 (4.9%) and ATM (4.4%) PV or likely pathogenic variants, which were not related to familial history. Based on our findings and that of the literature, we suggest including ATM gene among the panel of genes analyzed in PC patients pending the publication of prospective studies.

Prochiral hydrazones undergo efficient and highly selective hydrogenation in the presence of a chiral diphosphine ruthenium catalyst, yielding enantioenriched hydrazine products (up to 99% ee). The mild reaction conditions and broad functional group tolerance of this method allow access to versatile chiral hydrazine building blocks containing aryl bromide, heteroaryl, alkyl, cycloalkyl, and ester substituents. This method was also demonstrated on >150 g scale, providing a valuable hydrazine intermediate en route to an active pharmaceutical ingredient.

Atom transfer radical polymerisation ATRP has been applied to graft polymer chains from solid surfaces. For this purpose, new ATRP initiators have been designed which contain (i) functional sites to anchor the initiator covalently to the surface of an appropriate material, (ii) the active group which is capable to initiate the ATRP polymerisation process, and (iii) optionally a cleavable link which allows to detach the polymer grafts for polymer analysis. Surfaces have been decorated with the ATRP initiators and graft polymerisation as well as graft copolymerisation has been initiated from the surface. Grafting of various monomers, chain length and chain length distribution of the grafts is reported.

Die Nachfrage fur bildgesteuerte Nierenbiopsien hat durch die erhohte Detektion von Nierenlasionen zugenommen. Trotz der modernen Bildgebung konnen viele kleine Nierentumoren jedoch nicht als gutartig eingestuft werden, da sie von Nierenzellkarzinomen nicht unterscheidbar sind. Die Ultraschall- oder CT-gezielte Nierenbiopsie kann als sichere und genaue Methode in der Diagnostik von Nierenlasionen hilfreich bei der Wahl neuer ablativer und medikamentoser Therapieformen sein und unnotige Operationen vermeiden. Dieser Artikel beschreibt die klinischen Situationen, in denen eine bioptische Sicherung sinnvoll ist, und beleuchtet die Faktoren, die bei der Durchfuhrung einer Biopsie beachtet werden sollten.

For aluminum joining, the gas tungsten arc welding (GTAW) and the gas metal arc welding (GMAW) processes are widely used. The GTAW process is mainly used when high quality is required whereas the GMAW process allows higher throughput at a lower quality. Therefore, aluminum fabricators have to compromise between a high quality and a high productive welding process thus far. In this paper, a new GTAW welding variant is presented that operates in DCEP polarity (electrode as the anode) at high currents up to 450 A. The use of a second gas stream ensures a strong penetration and good arc stability. The welding performance of the new GTAW variant is compared to AC GTAW and pulsed GMAW. It enables high-quality welds for a wide thickness range between 2 and 10 mm at even higher welding speeds compared to GMAW.