Metabolic spatial connectivity in Amyotrophic Lateral Sclerosis as revealed by independent component analysis

Objectives. Positron emission tomography (PET) and volume of interest (VOI) analysis have recently shown in amyotrophic lateral sclerosis (ALS) an accuracy of 93% in differentiating patients from controls. The aim of this study was to disclose by spatial independent component analysis (ICA) the brain networks involved in ALS pathological processes and evaluate their discriminative value in separating patients from controls. Experimental design. Two hundred fifty-nine ALS patients and 40 age- and sex-matched control subjects underwent brain 18F-2-fluoro-2-deoxy-D-glucose PET (FDG-PET). Spatial ICA of the preprocessed FDG-PET images was performed. Intensity values were converted to z-scores and binary masks were used as data-driven VOIs. The accuracy of this classifier was tested versus a validated system processing intensity signals in 27 brain meta-VOIs. A support vector machine was independently applied to both datasets and the \u27leave-one-out\u27 technique verified the general validity of results. Principal observations: The 8 components selected as pathophysiologically meaningful discriminated patients from controls with 99.0% accuracy, the discriminating value of bilateral cerebellum/midbrain alone representing 96.3%. Among the meta-VOIs, right temporal lobe alone reached an accuracy of 93.7%. Conclusions: Spatial ICA identified in a very large cohort of ALS patients distinct spatial networks showing a high discriminatory value, improving substantially on the previously obtained accuracy. The cerebellar/midbrain component accounted for the highest accuracy in separating ALS patients from controls. Spatial ICA and multivariate analysis perform better than univariate semi-quantification methods in identifying the neurodegenerative features of ALS and pave the way for inclusion of PET in clinical trials and early diagnosis

Dissecting Representations

Choosing effective representations for a problem and for the person solving it has benefits, including the ability or inability to solve it. We previously devised a novel framework consisting of a language to describe representations and computational methods to analyse them in terms of their formal and cognitive properties. In this paper we demonstrate the application of this framework to a variety of notations including natural languages, formal languages, and diagrams. We show how our framework, and the analysis of representations that it enables, gives us insight into how and why we can select representations which are appropriate for both the task and the user

Disruption of Murine mp29/Syf2/Ntc31 Gene Results in Embryonic Lethality with Aberrant Checkpoint Response

Human p29 is a putative component of spliceosomes, but its role in pre-mRNA is elusive. By siRNA knockdown and stable overexpression, we demonstrated that human p29 is involved in DNA damage response and Fanconi anemia pathway in cultured cells. In this study, we generated p29 knockout mice (mp29GT/GT) using the mp29 gene trap embryonic stem cells to study the role of mp29 in DNA damage response in vivo. Interruption of mp29 at both alleles resulted in embryonic lethality. Embryonic abnormality occurred as early as E6.5 in mp29GT/GT mice accompanied with decreased mRNA levels of α-tubulin and Chk1. The reduction of α-tubulin and Chk1 mRNAs is likely due to an impaired post-transcriptional event. An aberrant G2/M checkpoint was found in mp29 gene trap embryos when exposed to aphidicolin and UV light. This embryonic lethality was rescued by crossing with mp29 transgenic mice. Additionally, the knockdown of zfp29 in zebrafish resulted in embryonic death at 72 hours of development postfertilization (hpf). A lower level of acetylated α-tubulin was also observed in zfp29 morphants. Together, these results illustrate an indispensable role of mp29 in DNA checkpoint response during embryonic development

Global institutions and local filtering: Introducing independent directors to Taiwanese corporate boards

Drawing on the idea of selective interaction between organizations and environments, the authors examine how organizations change their traditional practices when they are exposed to new institutional environments. In the context of corporate governance change in response to financial market globalization, they argue that global institutional influence is moderated by local corporate control contexts that function as filtering mechanisms. The authors empirically analyse the adoption of a new corporate governance practice, i.e., the initial introduction of independent directors, in Taiwanese public firms, where family governance has been a dominant governance model. The findings suggest that while firms exposed to US capital markets are more likely to adopt independent directors, this facilitating effect weakens when the firms are under strong family control and is amplified when they are unbound from local frameworks through the key leader???s education or their geographic context

Integrated Expression of Circulating miR375 and miR371 to Identify Teratoma and Active Germ Cell Malignancy Components in Malignant Germ Cell Tumors

Active germ cell malignancies express high levels of specific circulating micro-RNAs (miRNAs), including miR-371a-3p (miR371), which is undetectable in teratoma. Teratoma markers are urgently needed for theselection of patients and treatments because of the risk of malignant transformation and growing teratoma syndrome. To assess the accuracy of plasma miR375 alone or in combination with miR371 in detecting teratoma, 100 germ cell tumor patients, divided into two cohorts, were enrolled in a prospective multi-institutional study. In the discovery cohort, patients with pure teratoma and with no/low risk of harboring teratoma were compared; the validation cohort included patients with confirmed teratoma, active germ cell malignancy, or complete response after chemotherapy. The area under the receiver operating characteristic curve values for miR375, miR371, and miR371-miR375 were, respectively, 0.93 (95% confidence interval [CI]: 0.87-0.99), 0.59 (95% CI: 0.44-0.73), and 0.95 (95% CI: 0.90-0.99) in the discovery cohort and 0.55 (95% CI: 0.36-0.74), 0.74 (95% CI: 0.58-0.91), and 0.77 (95% CI: 0.62-0.93) in the validation cohort. Our study demonstrated that the plasma miR371-miR375 integrated evaluation is highly accurate to detect teratoma. PATIENT SUMMARY: The evaluation of two micro-RNAs (miR375-miR371) in the blood of patients with germ cell tumors is promising to predict teratoma. This test could be particularly relevant to the identification of teratoma in patients with postchemotherapy residual disease.info:eu-repo/semantics/publishedVersio

Internal and external cooling methods and their effect on body temperature, thermal perception and dexterity

© 2018 The Authors. Published by PLOS. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.1371/journal.pone.0191416© 2018 Maley et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Objective The present study aimed to compare a range of cooling methods possibly utilised by occupational workers, focusing on their effect on body temperature, perception and manual dexterity. Methods Ten male participants completed eight trials involving 30 min of seated rest followed by 30 min of cooling or control of no cooling (CON) (34C, 58% relative humidity). The cooling methods utilised were: ice cooling vest (CV0), phase change cooling vest melting at 14C (CV14), evaporative cooling vest (CVEV), arm immersion in 10C water (AI), portable water-perfused suit (WPS), heliox inhalation (HE) and ice slushy ingestion (SL). Immediately before and after cooling, participants were assessed for fine (Purdue pegboard task) and gross (grip and pinch strength) manual dexterity. Rectal and skin temperature, as well as thermal sensation and comfort, were monitored throughout. Results Compared with CON, SL was the only method to reduce rectal temperature (P = 0.012). All externally applied cooling methods reduced skin temperature (P0.05). Conclusion The present study observed that ice ingestion or ice applied to the skin produced the greatest effect on rectal and skin temperature, respectively. AI should not be utilised if workers require subsequent fine manual dexterity. These results will help inform future studies investigating appropriate pre-cooling methods for the occupational worker.This project is financially supported by the US Government through the Technical Support Working Group within the Combating Terrorism Technical Support Office.Published versio

Binding of Tetracycline and Chlortetracycline to the Enzyme Trypsin: Spectroscopic and Molecular Modeling Investigations

Tetracycline (TC) and chlortetracycline (CTC) are common members of the widely used veterinary drug tetracyclines, the residue of which in the environment can enter human body, being potentially harmful. In this study, we establish a new strategy to probe the binding modes of TC and CTC with trypsin based on spectroscopic and computational modeling methods. Both TC and CTC can interact with trypsin with one binding site to form trypsin-TC (CTC) complex, mainly through van der Waals' interactions and hydrogen bonds with the affinity order: TC>CTC. The bound TC (CTC) can result in inhibition of trypsin activity with the inhibition order: CTC>TC. The secondary structure and the microenvironment of the tryptophan residues of trypsin were also changed. However, the effect of CTC on the secondary structure content of trypsin was contrary to that of TC. Both the molecular docking study and the trypsin activity experiment revealed that TC bound into S1 binding pocket, competitively inhibiting the enzyme activity, and CTC was a non-competitive inhibitor which bound to a non-active site of trypsin, different from TC due to the Cl atom on the benzene ring of CTC which hinders CTC entering into the S1 binding pocket. CTC does not hinder the binding of the enzyme substrate, but the CTC-trypsin-substrate ternary complex can not further decompose into the product. The work provides basic data for clarifying the binding mechanisms of TC (CTC) with trypsin and can help to comprehensively understanding of the enzyme toxicity of different members of tetracyclines in vivo

A rapid and sensitive assay for quantification of siRNA efficiency and specificity

RNA Interference has rapidly emerged as an efficient procedure for knocking down gene expression in model systems. However, cross-reactivity, whereby multiple genes may be simultaneously targeted by a single short interfering RNA (siRNA), can potentially jeopardize correct interpretation of gene function. As such, it is essential to test the specificity of a siRNA prior to a full phenotypic analysis. To this end, we have adapted a reporter-based assay harnessing the sensitivity of luciferase activity to provide a quantitative readout of relative RNAi efficacy and specificity. We have tested different siRNAs directed against Thymosin β4 (Tβ4); determined their effectiveness at silencing Tβ4 and have both excluded off-target silencing of the Tβ4 homologue Thymosin β10 (Tβ10) and demonstrated partial knockdown of Tβ10 despite significant (12/23; 52%) sequence mismatch. This assay system is applicable to any RNAi study where there is a risk of targeting homologous genes and to the monitoring of off-target effects at the genome level following microarray expression profiling

Insertion of heterometals into the NifEN-associated iron–molybdenum cofactor precursor

The cofactors of Mo-, V-, Fe-dependent nitrogenases are believed to be highly homologous in structure despite the different types of heterometals (Mo, V, and Fe) they contain. Previously, a precursor form of the FeMo cofactor (FeMoco) was captured on NifEN, a scaffold protein for FeMoco biosynthesis. This all-Fe precursor closely resembles the Fe/S core structure of the FeMoco and, therefore, could reasonably serve as a precursor for all nitrogenase cofactors. Here, we report the heterologous incorporation of V and Fe into the NifEN-associated FeMoco precursor. EPR and activity analyses indicate that V and Fe can be inserted at much reduced efficiencies compared with Mo, and incorporation of both V and Fe is enhanced in the presence of homocitrate. Further, native polyacrylamide gel electrophoresis experiments suggest that NifEN undergoes a significant conformational rearrangement upon metal insertion, which allows the subsequent NifEN–MoFe protein interactions and the transfer of the cofactor between the two proteins. The combined outcome of these in vitro studies leads to the proposal of a selective mechanism that is utilized in vivo to maintain the specificity of heterometals in nitrogenase cofactors, which is likely accomplished through the redox regulation of metal mobilization by different Fe proteins (encoded by nifH, vnfH, and anfH, respectively), as well as the differential interactions between these Fe proteins and their respective scaffold proteins (NifEN and VnfEN) in the Mo-, V-, and Fe-dependent nitrogenase systems